\n<thead>\n<tr>\n<th>Term</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advice</td>\n<td>The code defined to run when the pointcut identifies a join point.</td>\n</tr>\n<tr>\n<td>Android</td>\n<td>Android is a popular mobile operating system developed by Google.</td>\n</tr>\n<tr>\n<td>Aspect Oriented Programming</td>\n<td>A programming method that is used to separate distinct tasks in a program that would otherwise be combined (tangled) together for convenience rather than functionality.</td>\n</tr>\n<tr>\n<td>Cold-Start Problem</td>\n<td>The condition created when there is insufficient information available to make decisions based upon inferences drawn from the data.</td>\n</tr>\n<tr>\n<td>Term</td>\n<td>Definition</td>\n</tr>\n<tr>\n<td>-----------------------------</td>\n<td>-------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Cold-Start State</td>\n<td>The period in time when a system is susceptible to the cold-start problem.</td>\n</tr>\n<tr>\n<td>Control Flow Graph</td>\n<td>A graph-based representation of the possible execution path(s) a function may take during execution.</td>\n</tr>\n<tr>\n<td>Cyber Foraging</td>\n<td>A method of extending a device’s capabilities by utilizing services and resources provided by devices in the nearby environment.</td>\n</tr>\n<tr>\n<td>Estimation</td>\n<td>Calculation that may be determined based upon a heuristic rather than an exhaustive calculation.</td>\n</tr>\n<tr>\n<td>Execution Time</td>\n<td>The amount of time it takes to execute a function from the time the function is called to when the function returns the results.</td>\n</tr>\n<tr>\n<td>Historical-Based Prediction</td>\n<td>A calculation that utilizes past known values for solving an problem to establish a relationship with future values often used with linear regression.</td>\n</tr>\n<tr>\n<td>Heuristic</td>\n<td>Method to quickly arrive at an answer; however, the answer may not be optimal. Heuristics generally are faster than the polynomial time required to solve the same problem for an optimal solution.</td>\n</tr>\n<tr>\n<td>Joinpoint</td>\n<td>Defines the position in an executing program or within a static program.</td>\n</tr>\n<tr>\n<td>Linear Regression</td>\n<td>A method used to model a relationship between one or more variables in a series of data points.</td>\n</tr>\n<tr>\n<td>NP-Complete</td>\n<td>A set of problems that can be solved in polynomial time.</td>\n</tr>\n<tr>\n<td>Pointcut</td>\n<td>An expression that defines a pattern to be matched against a program’s join points.</td>\n</tr>\n<tr>\n<td>Polynomial Time</td>\n<td>The time required to solve a problem expressed as a polynomial.</td>\n</tr>\n<tr>\n<td>Scheduling</td>\n<td>The process of determining where to execute a job so that it maximizes the overall goal of the system.</td>\n</tr>\n<tr>\n<td>Term</td>\n<td>Definition</td>\n</tr>\n<tr>\n<td>-----------------------------</td>\n<td>-----------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Surrogate</td>\n<td>An untrusted and unmanaged device that provides services to nearby clients.</td>\n</tr>\n<tr>\n<td>Remote Execution</td>\n<td>See Remote Procedure Call</td>\n</tr>\n<tr>\n<td>Remote Procedure Call</td>\n<td>A method of executing code on another device transparent of the network providing the illusion that the code were being executed locally.</td>\n</tr>\n<tr>\n<td>Fidelity</td>\n<td>The degree to which the quality delivered by a service compares to the quality of the original source.</td>\n</tr>\n<tr>\n<td>Partition</td>\n<td>The code selected to be offloaded to a surrogate for remote execution.</td>\n</tr>\n<tr>\n<td>Partitioning</td>\n<td>The process of selecting code that may be offloaded to a surrogate for remote execution in a cyber foraging system.</td>\n</tr>\n</tbody>\n</table>\nSummary\n\nMobile devices due to their size, weight, and power constraints typically lag behind stationary desktop workstations where processing power, memory, and storage capacity are concerned. The cyber foraging paradigm enables mobile devices to perform beyond their means by offloading code for remote execution. By remotely executing code, an application can conserve memory and battery power by allowing surrogate machines to expend the resources rather than requiring the mobile device itself to expend the precious resources. The remote execution of code may also allow for the overall execution time of the process to be shortened or the fidelity of the result to be increased due to the utilization of high-performance computers rather than the resource poor mobile device.\n\nA barrier to making offloading decisions in a cyber foraging system centered on obtaining enough information to make informed remote execution decisions. Given ample time and processing power, an execution scheduler could enumerate all available surrogates to determine the optimum surrogate to utilize in a given situation; however, as the number of surrogates increased, the time required to make such a determination would also increase and may become greater than what the end-user would be willing to accept. The price would also be increased in terms of both the processing power and the battery power that would be expended to make the decision. This could increase the cost of making the offloading decision beyond what would be saved by remotely executing the operation. This scenario may also be compounded by the cold-start problem. The cold-start problem could delay the availability of a newly arrived surrogate because the\nsystem does not have enough information available to schedule the newly arrived surrogate.\n\nThe achieved goal of this research was to investigate if metrics obtained from the run-time profiling of a Java program could be utilized by an estimation algorithm to help a cyber foraging system make beneficial offloading decisions during the cold-start state thereby increasing an application’s performance. The utilization of run-time metrics from the applications themselves provided a heuristic that did not require a-priori training, design-time information from the developer, or training effort from the end-user in order for the system to make informed offloading decisions that benefited the end-user.\n\nThe next chapter presents a review of the relevant literature and includes the cold-start problem, a review of the methods utilized to address the cold-start problem, including the use of default values or actions, historical-based algorithms, and heuristic-based approaches. The strengths and weaknesses of existing work are identified and gaps in the current approaches are identified and discussed.\nChapter 2\nReview of the Literature\n\nIntroduction\n\nThis research achieved the goal of increasing the performance of a cyber foraging application during the cold-start state by augmenting a history-based prediction algorithm with an estimation algorithm to avoid the cold-start state. The overall goal of utilizing cyber foraging in this research was to augment the capabilities of a resource constrained mobile device by utilizing resources present in the local environment, thereby enabling the constrained device to exceed its capabilities to better meet the needs of the user (Balan, et al., 2002). Past cyber foraging systems attempted to increase performance by minimizing an application’s execution time, minimizing energy consumption, or maximizing the fidelity of the content (Balan, et al., 2003; Cuervo, Balasubramanian, Cho, Wolman, Saroiu, Chandra, & Bahl, 2010; Kristensen & Bouvin, 2010; Verbelen, et al., 2012).\n\nThe scope of this literature review includes discussions on cyber foraging scheduling algorithms, which include scheduling algorithms from the related domains of grid computing, cloud computing, and peer-to-peer systems. This section begins with an overview of the cold-start state in cyber foraging systems and continues with discussions on scheduling algorithms that utilize default values or actions, historical-based prediction, and heuristics to make scheduling decisions.\n\nThe Cold-Start Problem\n\nThe cold-start problem, first discussed in recommendation systems, referred to a recommendation request for an item when recommendation data did not exist for the\nitem. This situation was often caused by the newness of the item and occurred when users did not have ample time to obtain, use, and comment on an item.\n\nThis scenario is common in websites that offer users’ ratings as part of a search option. The adverse effects of the cold-start problem in a retail scenario may cause consumers to not see new items if the search query contains a ranking attribute. This is a result of the system’s inability to provide a recommendation because there is no basis to form a recommendation (Schein, Popescul, Ungar, & Pennock, 2002).\n\n**Default-Based Algorithms**\n\nTo avoid the cold-start problem in a pervasive system, Serral et al. (2011) approached the problem by seeding a user preference dataset with the default actions to be used when a user preference was unavailable for a condition. By requiring the system developer to provide default actions for each possible scenario that could be encountered, the system avoided the cold-start problem by performing a default action until the system obtained enough data to learn a user’s preference (Serral, et al., 2011). This approach effectively addressed the cold-start problem at the user-level, but this approach had two consequences. First, it required the system developer to do additional work by providing default actions for each scenario and second, it pushed the cold-start problem from the user-layer into the system layer.\n\nBy utilizing default actions at the user-layer, the cold-start problem was effectively pushed into the cyber foraging level where it was reasonable to assume that if the system did not have enough information to make a recommendation to the user, it did not have enough information to make remote execution decisions on behalf of the user. The cold-start problem manifested itself in a cyber foraging system by the presence of\none or more surrogates in the environment that the system dad never interacted with before. This situation leads to the inability of the system to utilize the unknown surrogates when making scheduling decisions because of a lack of information about the surrogate. Without data about the surrogate, the system did not have the information required to determine if utilizing the new surrogate would be more or less beneficial than utilizing one of the known surrogates.\n\nNarayanan, et al. (2000) implemented a closed-system approach in the Odyssey system to avoid the cold-start state and constrained the system to a few known surrogates. The closed system approach used in Odyssey required that each surrogate be profiled in advance of joining the system. This advance profiling guaranteed that performance data about each surrogate would be available for use in scheduling decisions; however, the closed system approach has some disadvantages. The closed system approach is more suited to an individual’s home or workplace where mobility is limited rather than in highly mobile environment, such as a bus station or an airport terminal, where ad-hoc surrogate encounters are likely.\n\nThe Spectra system, the successor to the Odyssey system, utilized default models to avoid the cold-start state in the situation where historical data were unavailable to predict resource demand (Flinn, et al., 2002). In Spectra, resource monitors were used to share resource levels between cyber foraging clients and servers to model the resource demand for use in offloading decisions. In the absence of data, Spectra used default resource demand models that were based upon linear models of resource consumption. These model supply predictions for unknown values based upon execution history and extrapolation. If a prediction was requested and the system was unable to find a suitable\nmodel in the execution history, the system provided a generic estimate derived using linear regression. These demand models were similar to the default actions utilized by Serral et al. (2011), and shared the same weakness in terms of increased developer workload, because it required the developer to provide default monitors and models for each resource. Another concern with the use of default models was the appropriateness of the model across heterogeneous architectures.\n\nBalan et al. (2002) proposed using a brute force approach to surrogate utilization. The proposed method would have avoided the cold-start problem by utilizing every surrogate present in the environment and taking the first response. Because every available surrogate would be utilized regardless if historical execution data were available, this approach would typically yield beneficial performance. This approach would also have avoided the uncertainty that accompanied predictions and was immune to the cold-start problem; however, the brute force approach has a serious drawback: the approach does not scale well as the number of surrogates increases. As the number of surrogates increases, the communication, memory, and processing costs also increase due to the increased management load. This increasing cost could quickly outweigh the savings realized by offloading operations (Balan et al., 2002).\n\n**Historical-Based Algorithms**\n\nThe majority of the research efforts in cyber foraging surrogate selection has focused on the use of historical-based profiling techniques (Kafaie, Kashefi, & Sharifi, 2011). According to Kafaie, et al. (2011), the bulk of prior cyber foraging research has utilized online profiling, which requires the use of historical datasets in the prediction of the execution time of operations on remote surrogates. The utilization of historical-based\nalgorithms to make predictions was enticing because the predictions generally increase in accuracy over time as more data was accumulated (Gurun, Krintz, & Wolski, 2004). However, Flynn (2012) noted that the downside of using historical-based algorithms to make predictions was the cold-start problem. The algorithms required a training period (the cold-start problem) in order to obtain sufficient data for use in generating predictions (Flynn, 2012). This delay may have caused opportunities to use beneficial surrogates to be missed due to a lack of data.\n\nTo quantify this delay, the profiling process in the Odyssey system will be used as an example. Profiling a surrogate in the Odyssey system was performed offline and took approximately 10 seconds per surrogate. This assumed that a historical dataset was available. If a dataset was available, this file was provided as input to the profiler. However, if a historical dataset did not exist, it was generated by a training session. This training session required that a surrogate repeatedly execute the required operation(s), often with varying input, to generate a historical dataset for use in profiling (Narayanan, et al., 2000). The training and profiling of surrogates had the potential of introducing a substantial delay between when a surrogate was first encountered and when it became available for use. To avoid the training penalty, Huerta-Campea and Lee (2008) proposed incorporating the execution history from other surrogate devices during the integration of new surrogates into the system.\n\nWhen a device travels to a new environment, there is a high degree of probability that it will encounter new devices and be requested to perform operations that the device has never performed before (Kristensen & Bouvin, 2010). This situation is at the heart of the cold-start problem. By importing the execution logs of other devices, a surrogate\ncould minimize the time spent in the cold-start state and be available for use faster (Huerta-Canepa & Lee, 2008; Narayanan, et al., 2000). There are several unsolved challenges associated with this approach. First, conversions would be required to account for the performance differences between heterogeneous architectures, including differences introduced by CPU architecture and hardware speed. Second, performance metrics may be platform dependent would need to be converted from one platform to another to ensure that a reasonable comparison is made (Narayanan, et al., 2000).\n\nKristensen and Bouvin (2010) observed that the differences in platforms, including CPU architecture, compiler optimizations, and hardware architecture all contribute to the difficulty of finding a measure that can classify the power of heterogeneous machines. Such a classification would make it possible to group heterogeneous machines according to their respective power or throughput ratings.\n\n**Heuristic-Based Algorithms**\n\nAccording to Kafaie, et al. (2011), little work in cyber foraging surrogate selection has focused on utilizing approaches other than historical-based profiling. One reason for this may be due to the overall accuracy that these approaches offer over time (Gurun, et al., 2004). Although the delay imposed by profiling has been previously discussed, approaching the job of scheduling remote execution in a cyber foraging system from the perspective of grid computing provides a new perspective on the need to complete the scheduling task quickly.\n\nThe task of remote execution scheduling performed in a cyber foraging system can be viewed as a dynamic grid where the grid is comprised of surrogate devices. Job scheduling in a grid environment is an NP-complete problem that must be solved in a\nrelatively short period of time (Pooranian, Shojafar, Abawajy, & Singhal, 2013). Grid computing scheduling algorithms tend to favor optimizing makespan to reduce the overall execution time of a job stream, which is similar to the goal of reducing an application’s execution time in this research. According to Pooranian et al. (2013), since job scheduling is a NP-complete problem that must be solved in a relatively short period of time, the use of deterministic algorithms is not ideal. Even though a deterministic algorithm would eventually yield the correct answer, for a large number of nodes, the algorithm may not arrive at the solution in a reasonable amount of time. Solving this type of time-sensitive problem favors heuristic algorithms over deterministic algorithms.\n\nIn an effort to avoid profiling and the need for historical datasets, the adaptable offloading inference engine (OLLIE) dynamically offloads classes to surrogate devices in an effort to reduce the memory consumption of a mobile device (Gu, Nahrstedt, Messer, Greenberg, & Milojicic, 2003). OLLIE utilizes developer supplied class annotations, a fuzzy control inference engine, and developer supplied rules to control adaptation decisions that dynamically partition the executing application at runtime into objects that may be offloaded and accessed remotely via remote method invocation. The fuzzy inference engine utilized by OLLIE requires developer support to provide fuzzy logic rules to determine when to trigger offloading. The intriguing aspect of OLLIE from the perspective of this research is that no a-priori knowledge of the surrogates or execution history is required for the system to make beneficial offloading decisions. This is due in large part because the goal of conserving memory on the mobile devices can be realized by remotely instantiating an object on a surrogate machine given there is adequate\nmemory available on the surrogate. Adaptation is initiated by the single heuristic trigger of the available memory on a remote device to execute offloading.\n\nZhang, Kunjithapatham, Jeong, & Gibbs (2011) proposed an elastic application model that would automatically partition an application into individual weblets that could be dynamically and independently offloaded into the cloud to augment and conserve a mobile device’s resources. In an effort to determine the optimal balance between the number of offloaded weblets and locally executing code, a Naïve Bayesian Learning algorithm was utilized to keep the offloading balanced between the cloud and the mobile device. This was achieved by using a cost-based approach. The cost of specific resources and performance attributes were utilized by a learning algorithm and balanced against local resource measurements, historical performance data, and user preferences to control the partitioning of the application (Zhang, Kunjithapatham, Jeong, & Gibbs, 2011). Although this system utilizes a probabilistic approach over a deterministic approach to obtain the cost estimate this approach, like the Odyssey system, also suffers from the cold-start problem due to the dependence upon historical data to train the system before it can make predictions.\n\nKafaie, Kasheri, and Sharifi (2011) presented a cost-based approach to the cold-start problem by using the throughput of an operation executed on a specific device as a cost metric that could be utilized to make scheduling decisions. The cost metric, instructionPmSecond, was defined as the quotient of the number of elements that required processing and the time required to perform the operation (Kafaie, et al., 2011). Ideally, the value of instructionPmSection would be computed in an offline training session; however, if a new surrogate was encountered at runtime that did not have a value\nfor instructionPmSection, the system profiled the operation dynamically to obtain the cost metric. Although this approach suffered from the same scaling problem as the brute-force approach presented by Balan et al. (2002), it had two strengths. First, the system did not refuse to allow new surrogates to participate if it had not been profiled in advance. Second, the use of the metric (instructionPmSection) was preferable to the use of execution time itself. This was a step towards a device independent metric, which could be used to quantify the strength of the operation when executed on the surrogate.\n\nUsing a similar approach, Kristensen et al. (2010) utilized benchmarking to assign a strength rating to surrogates for use as a scheduling heuristic. This heuristic enabled the Scavenger system to make beneficial offloading decisions when there was a lack of historical information. Scavenger’s scheduler utilized two profiles: a peer-centric profile and a task-centric profile. The peer-centric profiles utilized historical information about the run-time of past executions in a (peer, task) pairing, while the task-centric profiles contained the weight of the task as if it were executed on a surrogate with a strength rating of 1. This scaling of the task weight by the strength rating of the surrogate allowed Scavenger’s scheduler to make judgments about the best surrogate to use when a peer profile was not available. The strength ratings of the surrogates were linear where a surrogate with a strength rating of 2 was twice as fast as a surrogate with a strength weighting of 1 (Kristensen, 2010).\n\nThe benchmarking approach utilized in the Scavenger system provided relatively sound guidance to the Scavenger’s scheduler; however, it was not perfect in every situation. Kristensen (2009) observed that architectural differences between platforms did influence the weights of tasks by as much as three times in some instances, which\nmay have led to inaccuracies in surrogate selection. Additionally, requiring the use of an external benchmarking application to obtain the surrogate strength was essentially an offline training phase.\n\nAn alternate approach to quantifying the strength of a surrogate was to quantify the resource demand of an operation. Binder and Hulaas (2006), in an effort to provide a cross-platform CPU consumption metric, utilized bytecode instruction counting as a method for quantifying CPU consumption of a Java application. The authors’, motivated by the high overhead of profiling and lack of portability of the JVM Profiler Interface, utilized bytecode rewriting to count the number of JVM instructions executed by each thread of execution in a Java application. This approach enabled Java applications to be profiled with moderate overhead ranging from 17% to 30% of the applications run-time (Binder & Hulaas, 2006). The ability to describe the CPU consumption of a Java bytecode in a platform neutral metric enabled the metric to be used directly without the need to perform conversions or weight the value to account for variations on device performance.\n\nA platform neutral metric avoided the need for platform specific conversions to account for architectural differences when estimating costs in a heterogeneous environment; however, the fact that the cost of an operation was often a function of the size of the input parameters also influenced the estimation. In an effort to glean cost relations from Java bytecode, Albert et al. (2007) utilized a CFG to convert Java bytecode into a traversable graph structure. The resulting CFG was used as input into a static analysis process designed to infer the operational complexity of the Java bytecode based upon the input parameters and the variables utilized to control branching and looping\nwithin the program. Although obtaining cost relations was an important component of\ndetermining the complexity of an operation, which in turn was required to determine the\nrunning time of the operation, the focus of this work was not to determine execution time,\nbut rather to determine which surrogate would potentially provide the fastest execution\ntime. A CFG was utilized to calculate the longest, shortest, and average path of\nexecution through an operation. The average path cost was utilized as a heuristic that\nindicated the overall cost of the operation rather than determining the exact cost of the\noperation using a deterministic method.\nChapter 3\nMethodology\n\nIntroduction\n\nThis research attained the goal of increasing an application’s performance during the cold-start state by designing and implementing an enhanced historical-based prediction algorithm. This algorithm utilized estimation for surrogate selection during the cold-start state of a cyber foraging application until the historical-based prediction algorithm accumulated enough execution history to make predictions. To provide an environment where the new algorithm could be evaluated, a Java-based cyber foraging system, called jScavenger, was developed using the Python-based Scavenger system developed by Kristensen (2009) as a model.\n\nThis chapter is organized as follows. First, a high-level overview of the jScavenger system will be presented, followed by a detailed discussion of the individual jScavenger components (the foraging application server, the jScavenger Surrogate client, and the cyber foraging application). Next, a discussion on the approaches used for profiling the operations and devices will be presented followed by discussions on the testing environment, performance evaluation, data collection, data analysis, and data verification processes.\n\njScavenger Overview\n\nThe jScavenger system was a Java-based client/server system where cyber foraging applications executing on a mobile device, such as a tablet or smartphone, remotely executed code in an effort to decrease the overall execution time of an application. Surrogate devices, located in the local environment, connected to the\njScavenger foraging application server (foraging server) to offer computational resources to cyber foraging applications. If the foraging server determined that the operation about to be performed would potentially run faster on a surrogate device, then the operation would be offloaded to a surrogate. The high-level organization of the jScavenger system is shown in Figure 1.\n\n\n\nIn Figure 1, the cyber foraging application depicted was an image manipulation application, which enabled the user to sharpen an image, adjust the contrast of an image, or convert the image to grayscale. This application was an Android application running on a smartphone, which allowed the user to select an image and the operation to perform upon the image. The application was also able to execute predefined scripts to automate the data collection phase of this research.\n\nImage manipulation was chosen because high-resolution cameras are standard on most mobile devices and the ability to manipulate images before they are uploaded to photo albums or social media sites is desirable; however, applying these operations to high-resolution images is still demanding and resource intensive for mobile devices in terms of time and energy (Kristensen & Bouvin, 2010). According to Kristensen et al.\ncyber foraging has been able to reduce the time it takes for a resource constrained device to perform a series of image operations on a high-resolution image from 150 seconds without cyber foraging to less than 20 seconds with cyber foraging.\n\nSurrogates in the jScavenger system functioned as remote procedure call (RPC) engines that accepted RPC requests, performed the requested operations, and returned the results. Each surrogate connected directly to the foraging server and maintained a library of operations that were available for use. When a surrogate connected to a foraging server the list of available operations on the surrogate were compared with the current requirements of the cyber foraging application(s) currently connected to the foraging server. If a surrogate was missing an operation that was currently required, the discrepancy was resolved by the surrogate downloading missing operation(s) from the foraging server. All surrogates in this research were assumed to be able to perform any operation that the cyber foraging application requested and each surrogate would have the required operations downloaded in advance.\n\nWhen a cyber foraging application attempted to perform an operation that was available on a surrogate, the foraging server intercepted the method execution request and determined if remote execution was beneficial. If remote execution was deemed to be potentially beneficial, the foraging server sent a RPC request to the selected surrogate along with the parameter data. The surrogate then performed the operation and returned the result to the foraging server. The foraging server then presented the result of the operation to the requesting application as if the operation was performed locally. Conversely, if remote execution was not deemed beneficial, then the application processed the operation locally.\nThe jScavenger Foraging Application Server\n\nThe jScavenger foraging server functioned as the cyber foraging resource manager for the mobile device by providing surrogate discovery and remote execution scheduling services to cyber foraging applications. The high-level architectural overview of jScavenger is shown in Figure 2.\n\nFigure 2 – The High-Level Architecture of jScavenger.\n\nThe Interface Between jScavenger and a Cyber Foraging Application\n\nDuring the execution of a cyber foraging application, the foraging server intercepted the method calls of the cyber foraging application and determined if remote execution was beneficial. This interface was implemented using Aspect Oriented Programming. In order to intercept the calls from a cyber foraging application, an AOP aspect called jScavengerMonitor was created. This aspect contained a pointcut, which defined a predicate that was used to match the method calls to be intercepted. The basic form of the pointcut is shown below.\npointcut InterceptCalls(): call (* *(..))\n\nThis pointcut called the advice method InterceptCalls if the current join point matched the predicate defined in the pointcut. In this case, the predicate was a wildcard that intercepted all method calls. The advice InterceptCalls contains the logic to locally execute or remotely execute the call using method names from the application’s tactic file and the list of available RPCs derived from the currently available surrogates. If the current method was available as a RPC and would potentially execute faster than local execution, then the request was submitted to the scheduler for execution; otherwise, the request was executed locally. The pseudocode of the InterceptCalls advice is shown in Figure 3.\n\n```\nObject around() : InterceptCalls()\n{\n Object value = null\n if( Scheduler.isAvailable(rpcname) )\n value = Scheduler.execute(rpcname, params)\n else\n value = proceed(params) // local execution\n return value\n}\n```\n\nFigure 3 – Pseudocode for InterceptCalls Advice\n\nIn this research, cyber foraging was considered a non-functional requirement of the user application. The use of AOP enabled the cyber foraging related code to be cleanly separated from the source code of the cyber foraging application (Irwin, Kickzales, Lamping, Mendhekar, Maeda, Lopes, & Loingtier, 1997). This separation of concerns allowed cyber foraging services to be provided transparently to the application, thus avoiding the need to directly modify the application to support cyber foraging (Satyanarayanan, 1996).\nThe single requirement jScavenver imposed upon a cyber foraging application to utilize cyber foraging was that the application developer must have provided a tactics file that contained the names of methods that could be offloaded to a surrogate. If an application did not supply a tactics file, then the application will execute without the benefits of cyber foraging. The tactics file will be discussed in detail in the Cyber Foraging Application section.\n\n**The jScavenger Execution Scheduler**\n\nThe jScavenger execution scheduler was responsible for determining the location where the current operation should be executed, remotely executing the operation (if applicable), and maintaining a log file that contains performance data about the system’s operation. This section contains details on the scheduler, the RPC execution mechanism, and the execution log file.\n\nThe execution scheduler worked with the discovery subsystem to maintain a list of operations that may be remotely executed and a list of surrogates capable of performing the operations. At runtime, when a new surrogate connected to the foraging server, a manifest of the available operations was presented to the discovery subsystem, which in turn registered the surrogate with the execution scheduler. The execution scheduler then used the manifest and the surrogate’s device name to maintain a list of operations that were currently available for remote execution. Each operation had the potential to be executed by none, one, or many surrogates. The relationship between the operations and surrogates is shown in Figure 4. For each operation, the associated surrogate list was maintained in order based upon the cost of performing the operation on the surrogate.\nThe execution scheduler in jScavenger determined whether to offload an operation to a surrogate or execute the operation locally using a cost-based metric. Kafaie, et al. (2011) developed a highly accurate solver that was able to successfully determine the most suitable surrogate to offload code execution using a cost-based model. Their cost-based solution defined cost functions for execution latency, computation time, communication time, and energy consumption based upon offline profiling. During experimentation, the authors’ solution selected the best location to execute the task with a degree of accuracy that performed as well as blind offloading.\n\nTwo of the drawbacks of this approach, which were addressed in this research, required the developer to annotate the complexity of each operation and the use of offline profiling to determine the speed of each device.\n\nBased upon the research conducted by Kafaie, et al. (2011), the expression used to determine if an operation should be offloaded was: IF $C_L > (C_R + C_C)$, where $C_L$ was the cost for a local task execution, $C_R$ was the cost for remote execution, and $C_C$ was the round-trip communication cost. If the estimated cost to perform the operation locally were greater than the sum of the estimated remote execution cost and the estimated round-trip communication cost, then the operation would be offloaded. The unit of measure for cost in this research was time, expressed in milliseconds. The method used to derive each cost varies by the scheduling algorithm that was used.\nThe jScavenger scheduling system contained three costing algorithms that were used to determine $C_L$ and $C_R$: historical, experimental, and random. The foraging server’s configuration file determined which scheduler was in use when the system was initialized.\n\nThe first algorithm, the historically-based algorithm, attempted to predict the $C_R$ as the execution time of a given operation by performing an ordinary least squares linear regression. The calculation was performed over a historical dataset consisting of the operation execution times for a specific surrogate and the size of the image in pixels. This mirrors the approach utilized by Narayanan, et al. (2000) to predict the remote execution time on the Odyssey system. This research followed suit by utilizing simple linear regression to predict the remote execution time of an operation using the number of pixels contained within the image as input. Linear regression was implemented in jScavenger using the Apache Commons Math3 library and the observation data was stored in the scheduler for each connected surrogate.\n\nThis approach follows the Odyssey system’s use of a linear regression-based algorithm that was able to predict the CPU demand for a given operation based upon the polygon count and resolution of the model to be processed. Using this approach, the Odyssey system achieved an error range of 10% to 24% (90th percentile relative error) of the predicted CPU demand vs. the observed CPU usage (Narayanan, et al., 2000). It should be noted that these results were obtained after the Odyssey system was trained on each surrogate so the system had adequate data to make offloading decisions.\n\nLike Odyssey, the jScavenger system’s implementation of this algorithm suffered from the cold-start problem because the system was not trained on each individual\nsurrogates prior to executing the experiments. Although this algorithm was based upon\nthe algorithm used by Odyssey; jScavenger, unlike Odyssey, accepted new surrogate\nconnections at run-time. The requirement to allow new surrogates to join the system at\nrun-time brought with it the cold-start problem due to the low probability that an\noperation was previously executed on the surrogate (Kristensen & Bouvin, 2010).\n\nTo address the cold-start problem, each new surrogate that did not have an\nexecution history was profiled. This profiling was performed in the background before\nthe surrogate was able to be utilized by the scheduler. The profiling was accomplished\nby requesting the surrogate to process two image files (one full-size and one thumbnail\nsize) using the current operation. All surrogates were considered to be in the cold-start\nstate until they attained a prediction error accuracy of 20% or less. Kafaie, et al. (2011)\nutilized a similar approach to gather performance information from an unknown\nsurrogate. This was accomplished by transferring a small profiling program to the\nsurrogate to gather performance metrics before the system could include the surrogate in\nscheduling calculations. Although this approach introduced additional overhead,\nexperimental results showed that the overhead could be justified by enabling the\nscheduler to make better offloading decisions.\n\nThe second algorithm, the experimental algorithm (Figure 5) utilized a heuristic to\nestimate the most beneficial surrogate to utilize while the historically based algorithm\nwas in the cold-start state. The heuristic estimated the remote execution cost as $C_R = \\frac{O_C}{D_S}$,\nwhere $O_C$ was the cost of the operation in terms of the average number of Java\nvirtual machine instructions contained in the operation and $D_S$ was the speed of the device\nin terms of the number of Java virtual machine instructions it demonstrated it could\nexecute per second. This heuristic was utilized until there was enough history accrued so that the historical-based algorithm would be sufficiently accurate. Using the error range from Odyssey as a guide, once the prediction error was below 20% of the observed value, the surrogate was considered to be beyond the cold-start state and the historical-based algorithm was utilized. The pseudocode for this algorithm is shown in Figure 5.\n\nKafaie, et al. (2011) utilized a similar metric to describe the performance of a device by performing offline profiling to obtain the number of data elements a device could perform in a second for a given task. The profiling utilized a developer supplied big-O expression for the time complexity behavior of the function and the element count of the input data as the workload. Although the term was named instructions per second, the value did not actually count machine instructions executed per second, but rather it represented the number of data elements that could be processed per second. This value was calculated by taking the number of elements in the data set divided by operation’s execution time. This approach enabled the authors’ to perform a brute force calculation over all surrogates to determine the best surrogate to utilize in a given situation (Kafaie, et al., 2011).\nThe use of a cost-based heuristic was utilized in the Scavenger system to enable the operations to be evaluated separately from the devices in what the authors’ termed multidimensional profiles (Kristensen & Bouvin, 2010). Scavenger’s use of multidimensional profiles enabled the characteristics of both the device and the operation to be reasoned about separately when making offloading decisions. For example, in the Scavenger system, a device with a strength level of 8 was considered to be twice as fast as a device with a strength level of 4. This type of direct comparison was not possible in a historical-based approach where the only data available was the time it took to execute the operation. By separating the characteristics of the device from the properties of the data to be acted upon, it became possible to estimate how a particular operation would perform on a specific device without actually performing the operation on the device.\n(Kristensen & Bouvin, 2010). Although the accuracy of historical-based approaches have proven themselves to be beneficial, they fall flat when presented with the cold-start problem (Kristensen & Bouvin, 2010).\n\nOne of the drawbacks of Scavenger’s approach is that each device must be benchmarked offline to obtain the device’s relative strength before it can participate in the system. The benchmarking suite NBench was used to provide the strength metric, which, according to the documentation, takes approximately 10 minutes to execute (Kristensen & Bouvin, 2010). The benchmarking requirement would delay devices that have not already been benchmarked by this specific software from participating in the system.\n\nThe jScavenger approach to profiling surrogates was as follows. First, the device was profiled to determine the estimated number of JVM instructions per second the device could perform. Second, the methods defined in the tactics file were profiled to determine the average number of JVM instructions for each operation. Once the device and operation profiles were obtained, the estimated execution time was calculated by dividing the operation profile cost by the device profile cost. The details on the methodologies used to profile the surrogate device and operations are discussed in the device profiling and operation profiling sections, respectively.\n\nThe third scheduling algorithm, the random algorithm, blindly selected a surrogate to use from the list of available surrogates. This algorithm utilized a random number generator that selects the surrogate to utilize for the current operation. This algorithm assumed that offloading was faster than local execution.\nThis research was conducted on a closed network to avoid unintended variations in network performance from influencing the overall performance of the testing environment. Because of this, the value of $C_C$ was not estimated and was considered a constant value for each surrogate. The actual observed value of $C_C$ was captured and evaluated to ensure that this assumption was valid.\n\nThe observed value of $C_C$ was determined by capturing the total latency (denoted by $C_T$) as seen from the application server and subtracting the remote execution time as reported by the surrogate. The calculation used to determine $C_C$ is illustrated in Figure 6.\n\nTwo image sizes were utilized in this research, which introduced variability in the transfer rates used over the TCP connections. The TCP communication protocol utilizes a sliding window, which can dynamically change the number of active packets allowed to be outstanding at a given time to increase throughput. Because of this, the transmission rate for larger files was higher than the rate for smaller files (Kafaie, et al., 2011).\n\n**Remote Execution**\n\nWhen the scheduler decided to offload an operation to a surrogate, it created an RPC request formatted as a XML document and sent the RPC request via a synchronous TCP socket to the surrogate for execution. The RPC was then decoded, executed, and a response was returned. A detailed discussion about how the remote execution was\n\n---\n\nFigure 6 – Calculating Round-Trip Communication Cost\nperformed on the surrogate is provided in the jScavenger surrogate section. An example of an RPC request/response pair is shown in Figure 7 and Figure 8, respectively.\n\n```xml\n<?xml version=\"1.0\" encoding=\"utf-8\"?>\n<request>\n <requestID>421</requestID>\n <requestType>RPC</requestType>\n <operationName>ImageLib.Contrast</operationName>\n <parameters>\n <parameter>\n <parameterName>RETURN_VALUE</parameterName>\n <parameterDirection>OUT</parameterDirection>\n <parameterDataType>byte[]</parameterDataType>\n <parameterValue>X62IBNhchbxBwbGhVwc==</parameterValue>\n </parameter>\n <parameter>\n <parameterName>IMAGE</parameterName>\n <parameterDirection>IN</parameterDirection>\n <parameterDataType>byte[]</parameterDataType>\n <parameterValue>W35IFNhchbCBwbGVhcw==</parameterValue>\n </parameter>\n </parameters>\n</request>\n```\n\nFigure 7 – XML RPC Request\n\nThe RPC Request XML document contained all the information required by the surrogate to perform the RPC. The important elements of the request document were the operationName and parameterValue elements. The operationName parameter passed the class name and the method name to be remotely executed. The parameterValues parameter contained binary data (byte and byte[]) in base64 to avoid the possibility of introducing invalid characters into the XML document.\nThe XML response reported upon the success or failure of the RPC. The response document contained an errorCode element, which contained the value of zero upon success, and a nonzero number upon failure. If the RPC failed, the errorDescription contained detailed information about the exception. The remote execution time (CR, in milliseconds) was returned in the executionTime parameter. If the operation contained output parameters or a return value, they were passed in the parameters array.\n\n**The Execution Log File**\n\nThe foraging server maintained a tilde delimited execution log, which enabled the performance of the system to be analyzed. The log file was called “server.log” by default and contained three record types: a request entry, a response entry, and a performance entry. The basic format for the execution log is shown below.\n\n```\nsequence number~record type~record data\n```\n\nThe sequence number was automatically generated for each record. The record type was one of the following: “1” for a request log entry, “2” for a response log entry, and “3” for a performance log entry. The record data varied by the record type. The format of the log file is shown in Table 1.\n<table>\n<thead>\n<tr>\n<th>Field Name</th>\n<th>Data Type</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Sequence Number</td>\n<td>Long integer</td>\n<td>Auto incrementing value</td>\n</tr>\n<tr>\n<td>Record Type</td>\n<td>Char</td>\n<td>1 = request 2 = response 3 = performance</td>\n</tr>\n<tr>\n<td>Record Data</td>\n<td>String</td>\n<td>Varies by Record Type</td>\n</tr>\n<tr>\n<td>when record data = 1</td>\n<td>XML String</td>\n<td>Request as defined by Figure 7</td>\n</tr>\n<tr>\n<td>when record data = 2</td>\n<td>XML String</td>\n<td>Response as defined by Figure 8</td>\n</tr>\n<tr>\n<td>when record data = 3</td>\n<td>Tilde Delimited String</td>\n<td>Performance Data String defined below</td>\n</tr>\n<tr>\n<td>Performance Data</td>\n<td>Delimited String (−)</td>\n<td>Contains the following delimited fields</td>\n</tr>\n<tr>\n<td>Operation Name</td>\n<td>String</td>\n<td>Contains the Class Name and Method name of the RPC in class.method format</td>\n</tr>\n<tr>\n<td>Image File Name</td>\n<td>String</td>\n<td>Contains the filename of the image</td>\n</tr>\n<tr>\n<td>Image File Size</td>\n<td>Integer</td>\n<td>Contains the file size in bytes</td>\n</tr>\n<tr>\n<td>Selected Surrogate Name</td>\n<td>String</td>\n<td>Selected Surrogate Name or Local</td>\n</tr>\n<tr>\n<td>Execution Latency (CT)</td>\n<td>Integer</td>\n<td>Operation latency in milliseconds</td>\n</tr>\n<tr>\n<td>Round-Trip Communication (CC)</td>\n<td>Integer</td>\n<td>Communication time in milliseconds</td>\n</tr>\n<tr>\n<td>Remote Execution Time (CR)</td>\n<td>Integer</td>\n<td>Remote execution time in milliseconds</td>\n</tr>\n<tr>\n<td>Connected Surrogates</td>\n<td>Delimited String (;)</td>\n<td>Contains the available surrogates</td>\n</tr>\n<tr>\n<td>Connected Surrogate Statuses</td>\n<td>Delimited String (;)</td>\n<td>Contains the statuses of all connected surrogates</td>\n</tr>\n</tbody>\n</table>\n\nTable 1 – The Execution Log File Format\n\nFor record types 1 and 2, the record’s data string contained the XML for the request and response, respectively. The performance record field’s value contained the following tilde delimited data items. The operation name, the image name, the image size in bytes, the surrogate selected for use, the latency of the execution, round-trip communication time, remote execution time, the connected surrogates, and the status of connected surrogates. This data enabled the performance of the system to be calculated for each of the scheduling algorithms. The overall latency (CT) was calculated as the summation of the round-trip communication time (CC) and the operation execution time (CR). The latency value represents the total time from when a user requested an operation...\nto be performed until the user received the results of the request. An example of the contents of the execution log file is shown in Appendix B.\n\n**Surrogate Discovery**\n\nThe surrogate discovery subsystem registered and unregistered surrogates with the execution scheduler. When a surrogate connected to jScavenger, the discovery subsystem, shown in Figure 9, registered the surrogate with the execution scheduler and informed the scheduler about the operations the surrogate could perform along with the speed of the surrogate.\n\n\n\nRather than manually orchestrating the availability of devices during the data collection stage of this research, the surrogate discovery module reads a driver file, which managed the availability of surrogates at runtime. The use of the driver file allowed for the same sequence of operations to be executed across all experimental scenarios.\n\nSurrogate status was changed after the completion of each operation execution. In this research, surrogates were assumed to be present for the entire duration of a remote execution request and would not be preempted. For example, the following discovery events will change the status of surrogates one, two, and three after the next 3 successive executions of the CONTRAST function.\n\nRPC CONTRAST SURROGATE-1=ONLINE, SURROGATE-2=OFFLINE, SURROGATE-3=ONLINE;\nRPC CONTRAST SURROGATE-1=OFFLINE, SURROGATE-2=OFFLINE, SURROGATE-3=ONLINE;\nRPC CONTRAST SURROGATE-1=ONLINE, SURROGATE-2=COLD-START, SURROGATE-3=OFFLINE;\n\nThe specification of the Discovery Simulation Driver file format is given in Figure 10 below.\n\nFigure 10 – Discovery Driver File Format Specification\n\n**The Application Tactics File**\n\nA cyber foraging application was required to provide the jScavenger system with an application tactics file in order to take advantage of cyber foraging services. The tactics file contained the signature for each method that could be offloaded to a surrogate.\n\nAs shown in Figure 2, the application tactics file was passed to the execution scheduler for use in the offloading decision. The execution scheduler monitored the method executions of a cyber foraging application and if the current method name matched a method in the tactics file, the method was intercepted for remote execution.\nA sample application tactic is shown below that describes an RPC called Grayscale that converts an image to grayscale and returns the converted image as a byte array. The format for the tactic file is shown in in Figure 11.\n\n\\[\n\\text{RCP byte[]} \\text{ ImageLib.Grayscale (IN byte[]} \\text{ image)}; \\\\\n\\]\n\nThe concept of application tactics was presented by Balan, et al. (2003) as a method by which application developers could hand-tune an application rather than have the system enumerate over all the possible ways (most of them infeasible) an application could be partitioned for remote execution. Tactics are the compromise between evaluating every possible combination at run-time, which may be computationally prohibitive, to hard-coding the application so that only one partitioning option was available (Balan, et al., 2003). The authors’ also recognized that creating a tactics file was a burden for the application developer; however, since the number of methods that could potentially be remotely executed was typically small compared to the overall size of the application’s source code, the added burden was generally manageable. To strengthen the argument for a developer supplied partitioning strategy, Chun, et al. (2010) stated that a hand-tuned partitioning strategy would likely outperform the partitioning generated by an algorithm.\n\nThe tactics file approach was selected for jScavenger due to the external nature of the annotations. The external nature of the tactics file was appealing because it allowed the behavior of the cyber foraging application to be changed without source code modifications.\nThe jScavenger Surrogate\n\nA jScavenger Surrogate functioned as a remote operation execution client for a jScavenger Foraging Application Server. Using surrogate devices for remote execution to increase an application’s performance was presented by Balan et al. (2002) as a component of the Spectra cyber foraging system and has been a necessary component of virtually all cyber foraging systems to date. The architecture of jScavenger’s surrogate was similar to the architecture used by the Scavenger system presented by Kristensen (2010). This section presents the architecture of the jScavenger surrogate and discusses the following components: the presence subsystem, the RPC execution subsystem, the operation manifest, the executable code store, the parameter data repository, and the local execution log. The architectural overview of jScavenger Surrogate is shown in Figure 12.\n**The Presence Subsystem**\n\nThe purpose of the presence subsystem was to detect and announce the presence and capabilities of a surrogate to the foraging server. For the purposes of this research, the surrogate presence subsystem was configured to connect to a specific jScavenger foraging server during initialization rather than listening for a broadcast from a local foraging server.\n\nEach surrogate maintained a manifest, which contained details of the operations that it was able to perform. When the surrogate was initialized, each object in the executable code store was examined using Java’s Reflection API and the public methods that were present in each class were identified and added to the manifest file. Any public method could be the target of an RPC request. The surrogate updated the manifest when the surrogate was initialized, when new class files were imported, and when class files were removed from the code store. The manifest maintained the type of call, the return\ndata type, the function name, the parameter direction, the parameter data type, and the parameter name.\n\nAn example of a manifest entry is shown below.\n\n RPC 567483 byte[] ImageLib.Contrast ( IN byte[] IMAGE );\n\nThe manifest entry indicates that a remote procedure call having 567,483 JVM instructions that returns a byte array called, “ImageLib.Contrast” is available. The RPC accepts a single byte array as the only parameter. The manifest file specification is shown in Figure 13.\n\nFigure 13 – Manifest File Specification\n\n**The Remote Execution Environment**\n\nThe remote execution environment accepted remote procedure call requests from the foraging server, performed the requested operation, and returned a response to the requestor. The format of the request and response documents is shown in Figures 7 and 8, respectively.\nWhen a surrogate received an RPC request, it first read the operationName property from the request document and verified that the operation was available. If the operation was available, then the surrogate extracted the parameter data from the request document and executed the operation. If the operation was not available, an error was generated and a response containing the error information was returned.\n\nThe Executable Code Store\n\nThe executable code store was the library where RPC operations that a surrogate can offer to foraging applications were stored. For the experiments in this research, the libraries were prepopulated with Java class files for the remote execution environment for use when servicing remote procedure calls.\n\nThe Parameter Data Repository\n\nThe parameter data repository was a temporary working storage area for the remote execution environment. Any data that was required to be persisted was stored in this area. Data was stored using the requestID followed by the parameter name. For example, if it was necessary to persist the image parameter of the request document shown in Figure 7, a file named 421.IMAGE.dat would be created to hold the parameter value. All files in this storage area were deleted when the surrogate was initialized.\n\nThe Surrogate Execution Log File\n\nEvery jScavenger surrogate maintained an execution log of each remote execution request received and every response sent. The surrogate’s execution log was identical to the foraging server’s log with the exception that performance records were not generated. The surrogate logging system only maintained logs for requests and responses. The surrogate log file was called, “surrogate.log.”\nThe jScavenger Cyber Foraging Application\n\nAs mentioned earlier, the cyber foraging application utilized in this research was an image manipulation application, which enabled the user to sharpen an image, adjust the contrast of an image, or convert the image to grayscale. The application was an Android application running on a smartphone that allowed the user to select an image and the operation to be performed upon the image. The application was also able to run in autopilot mode by executing a script that automated the image selection and operation requests. A prototype user interface of the testing tool is shown in Figure 14.\n\n\n\nFigure 14 – Image Manipulation Application\n\nIf a script file was selected for processing, the script file was expected to contain the image to be processed, the operation(s) to be performed upon the image, and the repetition count. The format of the script file uses name/value pairs and consisted of the\nfollowing named attributes. ScriptName, ScriptDescription, ImageName, OperationList, and RepeatCount. The ScriptName attribute contained the free-format name of the script. The ScriptDescription attribute provided a short description of the script. The ImageName contained the filename of the image to process. The RepeatCount property specified the number of times the operation(s) were to be performed upon the image defined in the ImageName property.\n\nThe script file was defined as follows. First, the ScriptName and ScriptDescription must be defined (in-order) on the first two non-commented lines of the script. The parameters ImageList, OperationName, and RepeatCount must follow in-order on the next three consecutive non-commented lines of the script. This parameter set may be repeated to enable multiple operations to be performed in a single test script.\n\nA sample script is shown in Figure 15.\n\n```plaintext\n;Start of script\nScriptName=Experimental.script\nScriptDescription=Experiential Testing Script that sharpens an image, adjusts the contrast, and adjusts the color image 50 times full-size and 50 times thumbnail (200x200) size.\n;\nImage=dog.png\nOperationList=Sharpen, Contrast, Color\nRepeatCount=50\n; End of script\n```\n\nFigure 15 – Image Manipulation Tool Automation Script Example\n\nWhen the mobile device takes a picture, the resulting image was stored at /storage/extSdCard/DCIM/Camera/. This location was considered the root folder for the cyber foraging application’s images. All input and output from the image manipulation tool defaulted to this location. The image manipulation tool supported the PNG graphic file format.\nOperation Profiling\n\nThe automatic profiling of operations to obtain the average number of JVM instructions that were expected to be executed when the operation was invoked was achieved using a CFG. Java bytecode was transformed into a CFG graph, which was traversed to quantify the number of JVM instructions that would be executed when the method was invoked. The use of bytecode was preferred over source code because access to the source code could not be guaranteed.\n\nAlbert et al. (2007) utilized CFGs in one step of an algorithm used to determine the cost relationship between methods and their input parameters. The authors’ work utilized CFGs to transform unstructured bytecode, which was difficult to analyze directly in part due to the use of the goto statement, into a traversable graph data structure that was suitable for static code analysis. The use of CFGs in this research was orthogonal to the work of Albert et al. (2007) in the sense that this research was concerned with obtaining a generic cost estimate of the operation’s execution for use as a heuristic. Although interesting, this research does not require the general relationship between the input parameters and the amount of work performed by the operation. The high-level algorithm used to profile operations in jScavenger follows:\n\n1. Convert the class containing the operation into a CFG.\n2. Generate a list of all possible paths from start to exit for the CFG.\n3. Calculate the average number of operations across all execution paths in the list.\n\nConsider the simple Java program shown in Figure 16. The entire program consists of 12 statements, but because of the if statement, not all of the statements will be\nexecuted when the program runs. Figure 17 shows the same program converted into a CFG. There are two execution paths from start to exit in this program. Each block contains statements, which are guaranteed to be executed. In Figure 17, the True and False arrows from the decision statement define a fork in the execution path. To determine the number of statements that could be executed, the number of statements contained in each block for each execution path will be summed. An average will then be calculated across all paths to provide a high-level approximation of the number of statements that will be executed. Using this technique, the estimated number of statements that will be executed when this program runs is 9 statements. This number represents the estimated cost of the operation.\n\n```java\nint a = 5;\nint b = 10;\nSystem.out.println(\"A = \" + a);\nSystem.out.println(\"B = \" + b);\n\nif( a > 5 )\n{\n a++;\n b--;\n}\nelse\n{\n a--;\n b++;\n}\nSystem.out.println(\"A = \" + a);\nSystem.out.println(\"B = \" + b);\n```\n\nFigure 16 - Simple Java program\nThe example above utilized Java source code to illustrate the CFG based approach to calculate the number of statements that could be executed. The actual approach utilized Java bytecode. The JVM instructions that would be executed by the JVM when the Simple Java Program was executed are shown in appendix A. Applying the technique discussed above to the output of the `javap` command yielded approximately forty-six JVM instructions that would be executed when the program runs.\n\nThe Apache Commons Byte Code Engineering Library (BCEL), which provided methods that enabled a Java program to inspect and manipulate Java bytecode, was utilized to extract the Java instructions from bytecode to calculate the average number of instructions at run-time. In future work, it would be advantageous for the Java compiler to generate this value during the compilation process and store the value as a method annotation.\n\n**Device Profiling**\n\nTo support the experimental scheduling algorithm, each device in the jScavenger system was profiled to obtain a measure of how powerful it was for executing operations.\nIn jScavenger, the speed of the surrogate was the number of JVM instructions the device demonstrated it could execute in one second. Binder and Hulaas (2006) first proposed using Java bytecode instruction counting as a method to obtain a cross-platform method of expressing CPU utilization rather than using the more traditional method of using CPU seconds. The benefit of using bytecode counting was that it effectively removed the variability introduced by the underlying hardware that influenced the CPU metric (Binder & Hulaas, 2006). This approach enabled devices to be rated by a common metric that does not have to be adjusted based upon the platform upon where the code was executed.\n\nKafaie, et al. (2011) utilized a similar approach by rating an operation’s speed on a specific device by how many input data elements could be processed by an operation in one second. This approach provided a metric that defined how an operation performed on a specific device; however, the approach requires that each operation be profiled per device prior to use. Kristensen and Bouvin (2010) utilized the third-party benchmarking suite NBench in the Scavenger system to provide a common rating of a device’s strength. The Scavenger system utilized the benchmark score as a device’s strength indicator, which allowed devices to be compared with one another. Both of these approaches provided a strength or speed indicator of the device; however, both approaches required manual developer support and an offline profiling session before the operations/devices were available for use.\n\nThe approach to profiling devices in this research aimed to eliminate the offline profiling phase by replacing it with an online profiling phase that was integrated into the application. This was achieved by profiling both the jScavenger foraging server and the jScavenger surrogate using the operation profiling method discussed previously to obtain\nthe number of instructions expected to be executed during the initialization of the jScavenger Foraging Application Server and the jScavenger Surrogate, respectively. During initialization, each application measured the time required to perform the initialization process and determined the speed of the current device using the number of instructions obtained by profiling the initialization code. The resulting JVM instruction execution speed was used to express the overall speed of the device.\n\nThe Testing Environment\n\nThe testing environment consisted of a wireless mobile device, a wireless access point, a switch, a DHCP server, and 5 surrogate devices. The testing environment is shown in Figure 18. The mobile device was a Samsung Galaxy SIII running Android 4.4, the wireless access point was a Linksys WAP54G, the switch was a Cisco 2950-12 12-port switch, and the 5 computers acting as surrogates were configured as follows:\n\n1. HP D530, Intel Pentium 4, 2.8 GHz, 1 GB RAM, Ubuntu 12.04 x86\n2. Power Mac G5 – Motorola PowerPC 970 G5, 1.6 GHz, 512 MB RAM, OS X 10.5.8\n3. Compaq 5700T, Intel Pentium 3, 550 MHz, 512 MB RAM, Windows XP\n4. Mac Pro Dual Intel Xeon Quad Core Processors, 2.8 GHz, 4 GB RAM, OS X 10.8.5\n5. HP 6000 Pro, Intel Core2 Quad Core, 2.83 GHz, 8GB RAM, Windows 7 x64\nThe test network was configured as follows. The wireless access point (WAP) was configured with a SSID of ‘cyberforaging’ and secured with WPA2 Personal encryption. The test network was available in an open environment where the wireless signal could not be masked. To prevent outside devices from interfering with the testing, Media Access Control (MAC) address filtering was enabled on the WAP so that only wireless devices included in the test were able to connect to the network. The network was not connected to either the internet or the enterprise network so a DHCP server was installed on the network to assign IP addresses based on each device’s unique MAC address. Only devices that were configured in the DHCP server’s configuration file were provided with an IP address.\n\nEach surrogate computer was configured to run Java version 7.0 SE. Each surrogate client installed was configured to connect to the foraging server running on the mobile device upon initialization. Each surrogate was configured with a secure shell server so the surrogates could be remotely administered.\n\n**Performance Evaluation**\n\nThree experiments were conducted to measure the performance of the new scheduling algorithm proposed in this research. The first experiment measured the performance of the cyber foraging application with the historical-based prediction algorithm. The second experiment measured the performance of the cyber foraging\napplication with the experimental algorithm. The third experiment measured the performance of the cyber foraging application with the random scheduling algorithm.\n\nEach experiment consisted of 4 scenarios, which collected data for specific operating conditions. The scenarios were disconnected operation, a saturated environment, a slowly churning and building environment, and a quickly churning environment. The structure of the each experiment is shown below followed by the description of each scenario.\n\n1. Experiment #1 – Historical Algorithm\n a. Scenario #1 – Disconnected Operation\n b. Scenario #2 – Saturated Environment\n c. Scenario #3 – Slowly Churning Environment\n d. Scenario #4 – Quickly Churning Environment\n\n2. Experiment #2 – Experimental Algorithm\n a. Scenario #1 – Disconnected Operation\n b. Scenario #2 – Saturated Environment\n c. Scenario #3 – Slowly Churning Environment\n d. Scenario #4 – Quickly Churning Environment\n\n3. Experiment #3 – Random Algorithm\n a. Scenario #1 – Disconnected Operation\n b. Scenario #2 – Saturated Environment\n c. Scenario #3 – Slowly Churning Environment\n d. Scenario #4 – Quickly Churning Environment\nThe disconnected operation scenario tested the system in an environment where there are no surrogates available. In this situation, all operations were executed locally, thus providing a baseline measurement of the cyber foraging application performance without cyber foraging assistance.\n\nThe saturated environment scenario tested the system in an over-provisioned environment where multiple surrogates were available. The purpose of this scenario was to measure the performance in a static system where there was no surrogate churn. This scenario was similar to a device being used at an individual’s home or workplace, where the presence of other devices can be predicted in advance and rarely changes.\n\nThe slowly churning environment scenario exercised the system in an environment where there were initially no connected surrogates and surrogates were slowly added to the system until all five surrogates were available for use. The purpose of this scenario was to measure the performance of the scheduling algorithm in an environment where changes were slow but constant. This scenario started out with no surrogates available and a new surrogate was added every 5 operations. This scenario parallels a business or social meeting place where people arrive sporadically and once present do not leave for an extended period.\n\nThe quickly churning environment scenario exercised the system in an environment where initially no surrogates were available. Surrogates were then simultaneously added and removed from the system after every few operations. The purpose of this scenario was to measure the performance of the scheduler in an environment where changes were fast-paced and constant, with possibly multiple surrogates arriving and departing simultaneously. This specific scenario started with no\nsurrogates online. After a random number of operations were performed (between 1 and 5), one surrogate was randomly selected to join the system and one currently connected surrogate was disconnected (if applicable). In this scenario, all surrogates were considered new to the system and training state will not be retained between a surrogate disconnection and a surrogate reconnection. This scenario parallels use in a public place such as a café or an airport terminal, where devices and their owners are highly mobile.\n\nThis research replicated the mechanics of the benchmarking approach used in Scavenger, where a series of image operations were sequentially performed on an image 50 times, once using a thumbnail representation of the image (200x200) and once using the full-sized image (Kristensen & Bouvin, 2010). According to Kristensen & Bouvin (2010), it is common for a series of operations to be performed upon an image before it was published. In the experiments outlined above, the image operations to be performed upon an image were to sharpen the image, adjust the contrast of the image, and to convert the image to grayscale. The images used were high-definition full-color pictures taken with an 8 Megapixel camera at a resolution of 3264x2448. The thumbnail images were derived from the full-size images at run-time.\n\n**The Data Collection Process**\n\nThe execution logs created while running the experiments was named according to the currently running experiment and scenario. All log files were named based upon the experiment and scenario being conducted as shown in Table 2. The log files collected during this process was formatted according to the execution log file format shown in Table 1.\n<table>\n<thead>\n<tr>\n<th>Experiment</th>\n<th>Scenario</th>\n<th>Log File Name</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Historical</td>\n<td>Disconnected Operation</td>\n<td>Historical.disconnected.log</td>\n</tr>\n<tr>\n<td>Historical</td>\n<td>Saturated Environment</td>\n<td>Historical.saturated.log</td>\n</tr>\n<tr>\n<td>Historical</td>\n<td>Slowly Churning Environment</td>\n<td>Historical.slowchurn.log</td>\n</tr>\n<tr>\n<td>Historical</td>\n<td>Quickly Churning Environment</td>\n<td>Historical.quickchrun.log</td>\n</tr>\n<tr>\n<td>Experimental</td>\n<td>Disconnected Operation</td>\n<td>Experimental.disconnected.log</td>\n</tr>\n<tr>\n<td>Experimental</td>\n<td>Saturated Environment</td>\n<td>Experimental.saturated.log</td>\n</tr>\n<tr>\n<td>Experimental</td>\n<td>Slowly Churning Environment</td>\n<td>Experimental.slowchurn.log</td>\n</tr>\n<tr>\n<td>Experimental</td>\n<td>Quickly Churning Environment</td>\n<td>Experimental.quickchrun.log</td>\n</tr>\n<tr>\n<td>Random</td>\n<td>Disconnected Operation</td>\n<td>Random.disconnected.log</td>\n</tr>\n<tr>\n<td>Random</td>\n<td>Saturated Environment</td>\n<td>Random.saturated.log</td>\n</tr>\n<tr>\n<td>Random</td>\n<td>Slowly Churning Environment</td>\n<td>Random.slowchurn.log</td>\n</tr>\n<tr>\n<td>Random</td>\n<td>Quickly Churning Environment</td>\n<td>Random.quickchrun.log</td>\n</tr>\n</tbody>\n</table>\n\nTable 2 – Log File Naming by Experiment and Scenario.\n\n**The Data Analysis Process**\n\nThe data captured by performing the experiments was imported into a Microsoft Access database, labeled by experiment, and processed to complete the following analysis. The analysis consisted of a high-level overview of the results, an analysis of the historical algorithm, an analysis of the experimental algorithm, a brief analysis of the random algorithm, and a discussion of the combined analysis of all three algorithms.\n\nFirst, a high-level overview of the experiments was presented. This overview included the execution time of each scheduling algorithm. The results were graphed to present a high-level performance overview of each scheduling algorithm. Next, the performance of each scheduling algorithm was graphed to compare the performance of each operational scenario. Finally, the detailed execution time of each experimental scenario was presented, which included both the local and remote execution time.\nThe historical scheduling algorithm was examined by reviewing the surrogate training and selection activity for each of the scenarios. For each scenario, a graph was generated that presented both the local execution time and the remote execution time for each scenario. This enabled the surrogate selection and training activities to be compared against the expected surrogate selection and training activities.\n\nThe experimental scheduling algorithm was analyzed by first presenting the surrogate configuration profiles along with the speed ranking of each surrogate. A table was generated from the random saturated scenario that included multiple operation executions on each surrogate to obtain actual execution metrics. The data were sorted by execution time to compare the calculated speed vs. the actual execution time required by each operation. Each scenario was then graphed in the same fashion as the historical scheduling algorithm so that the surrogate selection could be compared with the expected results.\n\nThe random scheduling algorithm was not graphed due to the random nature of surrogate selection. To assess this algorithm, the overall execution time for each scenario was compared against the historical and experimental algorithms.\n\nAll three scheduling algorithms were compared against each other by superimposing all of the performance graphs for each scenario. The resulting graphs illustrated the performance of each algorithm by operational scenario. This allowed the performance to be reviewed by operation.\n\n**Data Verification**\n\nTo ensure that the HotSpot JVM was not influencing the results, each JVM was configured with the –Xint run-time parameter to disable just in time (JIT) compilation.\nOn the Android platform, this was accomplished by using the android:vmSafeMode=\"true\" property of the Android application manifest configuration file. Additionally, the JVM were configured to display compilation messages using the –XX:-PrintCompliation parameter to ensure that the JVM did not perform optimizations that would influence the execution time of the operations.\n\n**Resources**\n\nThe computing resources required to complete this dissertation consisted of a development machine, Java application development software, Android application development software, a wireless access point, a switch, networking accessories, an Android-based cell phone, and 6 network ready personal computers capable of running Java 7.0.\n\nThe development environment consisted of Java 7.0 (http://java.oracle.com), the Android Developer Tools (ADT) bundle (http://dl.google.com/android/adt/adt-bundle-windows-x86_64-20131030.zip), and the Eclipse Java IDE (http://www.eclipse.org/downloads/). The test network infrastructure consisted of a Linksys WAP54G, and a Cisco 2950-12 switch with the required configurations and cabling necessary to create an isolated local area network.\n\n**Summary**\n\nThis research developed and implemented an enhanced historical-based prediction algorithm. This algorithm utilized estimation for surrogate selection during the cold-start state of a cyber foraging application until the historical-based prediction algorithm accumulated enough execution history to make predictions. To provide an environment\nwhere the new algorithm could be evaluated, a Java-based cyber foraging system, called jScavenger, was developed.\n\nThree scheduling algorithms were utilized by jScavenger to test the performance of each algorithm. In addition to the experimental algorithm, the additional scheduling algorithms were a historical-based algorithm and a random-based algorithm. The experimental algorithm utilized a heuristic based upon the rate at which a surrogate demonstrated that it could execute JVM instructions and the number of JVM instructions contained within an operation to choose a surrogate when a historical prediction was unavailable. The historical-based algorithm utilized historical predictions to select surrogates and when a surrogate was unable to provide a prediction, a training session was initiated to obtain historical measurements. The random-based algorithm chooses surrogates based upon a random number generator.\n\nEach scheduling algorithm was utilized in 4 testing scenarios, each of which collected data for specific operating condition. The scenarios were disconnected operation, a saturated environment, a slowly churning and building environment, and a quickly churning environment. The disconnected operation scenario tested the system in an environment where there are no surrogates available. The saturated environment scenario tested the system in an over-provisioned environment where multiple surrogates were available. The slowly churning environment scenario exercised the system in an environment where there were initially no connected surrogates and surrogates were slowly added to the system until all five surrogates were available for use. The quickly churning environment scenario exercised the system in an environment where initially no\nsurrogates were available. Surrogates were then simultaneously added and removed from the system after every few operations.\n\nThe results of each scheduler’s performance of each operational scenario were analyzed independently, then against each of the other two scheduling algorithms. This allowed for the scheduler’s performance with each operational scenario to be verified and then the performance to be compared with the other algorithms.\nChapter 4\n\nResults\n\nIntroduction\n\nThree experiments were conducted based upon the methodology described in Chapter 3. The results of the experiments are discussed in the following sections.\n\n- Overview of the Experimental Results\n- Experiment 1 – Historical Scheduling Algorithm\n- Experiment 2 – Experimental Scheduling Algorithm\n- Experiment 3 – Random Scheduling Algorithm\n- A Performance Comparison of the Experiments\n\nOverview of the Experimental Results\n\nThe execution time required to complete all three experiments is shown in Figure 19. The overall execution time is presented for each experiment grouped by the time spent executing operations locally \\( (C_T) \\) and the time spent executing operations remotely \\( (C_R) \\). Additionally, the time required for the experiments to be run in disconnected from the network is also presented as a baseline measurement. The network communication overhead is not included in the calculations.\nOverall, the experimental scheduling algorithm required 7.38 hours to execute the 1200 operations in the testing scenario, the historical scheduling algorithm required 8.25 hours to execute the same set of 1200 operations, and the random scheduling algorithm required 10.2 hours to complete the operations. In disconnected mode, the same 1200 operations took 15.84 hours to complete running solely on the local device. Figure 20 presents the performance of each scenario by experiment.\nTable 3 presents the summarized data for each experiment broken down by scenario. In addition to providing data by scenario, the breakdown of the local and remote execution times are shown along with the total time.\n\n<table>\n<thead>\n<tr>\n<th>Experiment</th>\n<th>Scenario</th>\n<th>Local Operation Execution Time (C_T hours)</th>\n<th>Remote Operation Execution Time (C_R hours)</th>\n<th>Total Time C_T + C_R (hours)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Historical</td>\n<td>Disconnected</td>\n<td>5.28</td>\n<td>0.00</td>\n<td>5.28</td>\n</tr>\n<tr>\n<td></td>\n<td>Saturated</td>\n<td>0.00</td>\n<td>0.43</td>\n<td>0.43</td>\n</tr>\n<tr>\n<td></td>\n<td>Slow Churn</td>\n<td>0.32</td>\n<td>0.43</td>\n<td>0.75</td>\n</tr>\n<tr>\n<td></td>\n<td>Quick Churn</td>\n<td>1.18</td>\n<td>0.61</td>\n<td>1.79</td>\n</tr>\n<tr>\n<td><strong>Total Time</strong></td>\n<td></td>\n<td><strong>6.78</strong></td>\n<td><strong>1.47</strong></td>\n<td><strong>8.25</strong></td>\n</tr>\n<tr>\n<td>Experimental</td>\n<td>Disconnected</td>\n<td>5.28</td>\n<td>0.00</td>\n<td>5.28</td>\n</tr>\n<tr>\n<td></td>\n<td>Saturated</td>\n<td>0.00</td>\n<td>0.43</td>\n<td>0.44</td>\n</tr>\n<tr>\n<td></td>\n<td>Slow Churn</td>\n<td>0.21</td>\n<td>0.43</td>\n<td>0.64</td>\n</tr>\n<tr>\n<td></td>\n<td>Quick Churn</td>\n<td>0.28</td>\n<td>0.74</td>\n<td>1.02</td>\n</tr>\n<tr>\n<td><strong>Total Time</strong></td>\n<td></td>\n<td><strong>5.77</strong></td>\n<td><strong>1.61</strong></td>\n<td><strong>7.38</strong></td>\n</tr>\n<tr>\n<td>Random</td>\n<td>Disconnected</td>\n<td>5.28</td>\n<td>0.00</td>\n<td>5.28</td>\n</tr>\n<tr>\n<td></td>\n<td>Saturated</td>\n<td>0.00</td>\n<td>1.65</td>\n<td>1.65</td>\n</tr>\n<tr>\n<td></td>\n<td>Slow Churn</td>\n<td>0.31</td>\n<td>1.48</td>\n<td>1.79</td>\n</tr>\n<tr>\n<td></td>\n<td>Quick Churn</td>\n<td>0.08</td>\n<td>1.40</td>\n<td>1.48</td>\n</tr>\n<tr>\n<td><strong>Total Time</strong></td>\n<td></td>\n<td><strong>5.67</strong></td>\n<td><strong>4.53</strong></td>\n<td><strong>10.20</strong></td>\n</tr>\n</tbody>\n</table>\n\nTable 3 – Overall Performance by Experiment and Scenario\nFigure 21 shows the execution results of performing all three image operations on a disconnected surrogate using the full-sized image. Since no cyber foraging was involved, this result is common to each of the three experiments. The graph clearly shows the execution for each operation and transitions between the operations running solely on the local device.\n\n\n\n**Figure 21 – Disconnected Operation Performance**\n\n**Experiment 1 – Historical Scheduling Algorithm**\n\nFigure 22 shows the results of the historical scheduling algorithm in the saturated scenario where the image manipulation operations were executed on the full-size image. The graph clearly shows the expected local executions at the transitions between operations while the surrogates are trained. Training occurs at the first operation because\nno operations have been performed on any of the surrogate devices. Training occurs again at operation 51 because the operation changes from sharpening to contrast and execution history for the contrast operation do not exist. The final training session occurs at operation count 101 when the operation changes from contrast to grayscale due to a lack of execution history. As expected, the scheduler quickly determines the beneficial surrogate to utilize based upon the training. Overall, there are 15 individual training sessions during this experimental run.\n\nFigure 22\n\nFigure 23 shows the results of the historical scheduling algorithm in the slowly churning scenario, where image manipulation operations were executed on the full-size image. The graph shows the expected local executions at the start of the experiment.\nwhile no surrogates are available and again while the initial training is performed once a surrogate becomes available. At operation 13, a new, more powerful surrogate becomes available. The system spawns a background thread to negotiate and train the new surrogate (not shown). At operation 14, the scheduler selects the newly available surrogate and begins offloading operations to that surrogate. New surrogates continue to arrive during the remainder of the test, but they are all less powerful than the currently selected surrogate. The scenario repeats itself for the subsequent operations and the same surrogate switch occurs again at operations 64 and 115 (denoted by the red asterisk). For this scenario, there are 14 individual training sessions during this experimental run.\n\nFigure 23 – Historical Scheduling Algorithm Slowly Churning Operation Performance\nFigure 24 shows the results of the historical scheduling algorithm in the quickly churning scenario where the image manipulation operations were executed on the full-size image. The graph shows the expected local executions at the start of the experiment when there are no surrogates available and while the initial training is performed. Since the availability of the surrogates is random and they connect and disconnect frequently, the amount of local execution is noticeably higher due to the churn. At operation 19, an abnormally long running remote execution is shown. This spike, although large, is still faster than the observed local executions. It is also noteworthy because it represents a missed opportunity. At operation 18, a new and more powerful surrogate arrived, but it was not selected for remote execution because training had not yet been completed. Overall, the training overhead for this scenario involves 64 individual surrogate training sessions and 68% of all operation executions occur when there is a minimum of one surrogate in training.\nFigure 24 - Historical Scheduling Algorithm Quickly Churning Operation Performance\nExperiment 2 – Experimental Scheduling Algorithm\n\nThe experimental scheduling algorithm chooses a surrogate based upon the average speed at which a surrogate can process Java instructions. The average number of Java bytecode instructions obtained by traversing the CFG graph for the operations contrast, grayscale, and sharpen is 227, 174, and 285, respectively. The initialization routine for the surrogate client consists of an average of 930 JVM instructions to be executed upon startup. A profile of each surrogate and the surrogate’s calculated speed rating is shown in Table 4.\n\n<table>\n<thead>\n<tr>\n<th>Surrogate</th>\n<th>Speed Rating</th>\n<th>CPU</th>\n<th>CPU Speed</th>\n<th>RAM</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>S-1</td>\n<td>22</td>\n<td>Intel Pentium 4</td>\n<td>2.8GHz</td>\n<td>1 GB</td>\n</tr>\n<tr>\n<td>S-2</td>\n<td>9</td>\n<td>PowerPC 970</td>\n<td>1.6GHz</td>\n<td>512 MB</td>\n</tr>\n<tr>\n<td>S-3</td>\n<td>4</td>\n<td>Intel Pentium 3</td>\n<td>550 MHz</td>\n<td>512 MB</td>\n</tr>\n<tr>\n<td>S-4</td>\n<td>44</td>\n<td>Intel Quad Core Xenon</td>\n<td>2.8GHz</td>\n<td>4 GB</td>\n</tr>\n<tr>\n<td>S-5</td>\n<td>58</td>\n<td>Intel Core2 Quad Core</td>\n<td>2.83GHz</td>\n<td>8 GB</td>\n</tr>\n<tr>\n<td>local</td>\n<td>16</td>\n<td>ARM Cortex-A9 Quad Core</td>\n<td>1.4GHz</td>\n<td>1 GB</td>\n</tr>\n</tbody>\n</table>\n\nTable 4 – Surrogate Profile\n\nEvery surrogate was utilized in the random scheduling algorithm execution, which enabled the average actual execution time to be measured for each operation on every surrogate device. The average operation execution time for each surrogate along with the surrogate’s speed ranking is shown in Table 5. The results are discussed next.\n\nAs expected, the contrast operation’s actual execution time on each surrogate followed the speed ranking for the decision making with S-5 being the fastest surrogate for the contrast operation to surrogate S-3 being the slowest surrogate for the contrast operation. The speed rankings for the surrogate using the speed heuristic were consistent with the observed execution times for the operation. The grayscale operation ranked surrogate S-5 as the fastest surrogate to S-3 being the slowest surrogate. The speed\nrankings for the surrogate using the speed heuristic were consistent with the observed execution times for the operation with one exception. For the grayscale operation, the local execution speed was ranked higher than the observed execution placed it in the rankings. The sharpen operation ranked surrogate S-5 as the fastest surrogate to local execution being the slowest surrogate. The speed rankings for the surrogate using the speed heuristic were consistent with the observed execution times for the operation with the exception of 2 surrogates. For the sharpen operation, both surrogates S-2 and S-3 were ranked slower than their observed executions. These inconsistencies offer opportunities for future research that might include hardware variation between machines.\n## Average Surrogate Operation Execution Time\n\n### Full-Size Image\n\n<table>\n<thead>\n<tr>\n<th>Operation</th>\n<th>Surrogate</th>\n<th>Surrogate Speed</th>\n<th>Operation Speed</th>\n<th>Execution Time (ms)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Contrast</strong></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>S-5</td>\n<td>58</td>\n<td>3.90</td>\n<td>9,247</td>\n<td></td>\n</tr>\n<tr>\n<td>S-4</td>\n<td>44</td>\n<td>5.16</td>\n<td>9,521</td>\n<td></td>\n</tr>\n<tr>\n<td>S-1</td>\n<td>22</td>\n<td>10.32</td>\n<td>43,199</td>\n<td></td>\n</tr>\n<tr>\n<td>local</td>\n<td>16</td>\n<td>14.19</td>\n<td>47,570</td>\n<td></td>\n</tr>\n<tr>\n<td>S-2</td>\n<td>9</td>\n<td>25.20</td>\n<td>64,476</td>\n<td></td>\n</tr>\n<tr>\n<td>S-3</td>\n<td>4</td>\n<td>56.75</td>\n<td>122,996</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>Grayscale</strong></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>S-5</td>\n<td>58</td>\n<td>3.00</td>\n<td>4,770</td>\n<td></td>\n</tr>\n<tr>\n<td>S-4</td>\n<td>44</td>\n<td>3.96</td>\n<td>5,068</td>\n<td></td>\n</tr>\n<tr>\n<td>S-1</td>\n<td>22</td>\n<td>5.77</td>\n<td>15,887</td>\n<td></td>\n</tr>\n<tr>\n<td>S-2</td>\n<td>9</td>\n<td>14.11</td>\n<td>22,568</td>\n<td></td>\n</tr>\n<tr>\n<td>local</td>\n<td>16</td>\n<td>7.94</td>\n<td>32,646</td>\n<td></td>\n</tr>\n<tr>\n<td>S-3</td>\n<td>4</td>\n<td>31.75</td>\n<td>51,926</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>Sharpen</strong></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>S-5</td>\n<td>58</td>\n<td>4.91</td>\n<td>17,729</td>\n<td></td>\n</tr>\n<tr>\n<td>S-4</td>\n<td>44</td>\n<td>6.48</td>\n<td>20,977</td>\n<td></td>\n</tr>\n<tr>\n<td>S-2</td>\n<td>9</td>\n<td>31.67</td>\n<td>36,658</td>\n<td></td>\n</tr>\n<tr>\n<td>S-1</td>\n<td>22</td>\n<td>12.96</td>\n<td>59,308</td>\n<td></td>\n</tr>\n<tr>\n<td>S-3</td>\n<td>4</td>\n<td>71.25</td>\n<td>210,126</td>\n<td></td>\n</tr>\n<tr>\n<td>local</td>\n<td>16</td>\n<td>17.81</td>\n<td>298,367</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n### Table 5 – Surrogate Performance\n\nThe results of the experimental scheduling algorithm in the saturated scenario are presented in Figure 25. In this scenario, the image manipulation operations were performed upon the full-size image where all the surrogates are online and available. As expected, the scheduler quickly determined the beneficial surrogate to utilize without performing local executions.\nFigure 25 - Experimental Scheduling Algorithm Saturated Operation Performance\n\nFigure 26 shows the results of the experimental scheduling algorithm in the slowly churning scenario, where the image manipulation operations were executed on the full-size image as surrogates slowly join the system. The graph shows the expected local executions at the start of the experiment when no surrogates are online. At operation 13, a more powerful surrogate became available and was immediately utilized by the scheduler to execute operations. New surrogates continued to arrive during the remainder of the test, but they were all less powerful than the current surrogate was. The scenario repeats itself for the subsequent image operations and the same surrogate switch occurs again at operations 63 and 113 (denoted by the red asterisk).\nFigure 26 - Experimental Scheduling Algorithm Slowly Churnung Operation Performance\n\nFigure 27 shows the results of the experimental scheduling algorithm in the quickly churning scenario, where the image manipulation operations were executed on the full-size image. The graph shows the expected local executions at the start of the experiment when no surrogates are online. Overall, the experimental algorithm produced the best performance over the historical and random algorithms. While the experimental scheduling algorithm picked the proper surrogate based upon the rankings, the performance of three surrogates that were chosen for the contrast and grayscale operations show that in hindsight the choices could have been better.\nFor the sharpen operation, at operation 4 the local surrogate was chosen by the experimental scheduling algorithm for the contrast operation over surrogate S-3 because it is ranked higher. In reality, surrogate S-3 demonstrated better performance in the post-execution review. For operations 21 through 24, surrogate s-1 was chosen over surrogate s-2 where in reality, surrogate s-2 demonstrated better performance. At operation 33, the local device was chosen over surrogate s-2 when s-2 demonstrated better performance. For operations 34-36 and 39-40, s1 was chosen when s2 would have been preferred. For the grayscale operation, the scheduler chose surrogate s-1 over s-2 at operation 109 when s-2 would have provided better performance.\n\nFigure 27 - Experimental Scheduling Algorithm Quickly Churning Operation Performance\nExperiment 3 – Random Scheduling Algorithm\n\nThe random scheduling algorithm randomly selected a surrogate to perform an operation from the pool of available surrogates. This algorithm assumes that offloading is always beneficial.\n\nThe disconnected scenario performed all operations locally due to the lack of available surrogates taking 5.28 (Table 3) hours to complete all 1200 operations. The saturated algorithm performed all 1200 operations on surrogate devices taking 1.65 hours to complete compared to the 0.53 hours for the historical algorithm and 0.44 hours for the experimental algorithm. The slowly churning scenario executed all but 9 operations on surrogate devices and took 1.79 hours to complete compared to the 0.75 hours for the historical algorithm and 0.64 hours for the experimental algorithm. The quickly churning scenario executed all but 1 operation on surrogate devices and took 1.48 hours to complete, which beat the historical algorithm’s time of 1.79 hours but fell short of the experimental algorithm’s time of 1.02 hours to complete. This algorithm’s success at beating the historical algorithm using blind chance points to the benefits of cyber foraging and strengthens the support for additional research into using a lightweight heuristic to guide offloading sections. Although the random algorithm potentially chooses slower surrogates when faster surrogates were available, it shows that a minimal overhead algorithm can rival historical-based algorithms in certain scenarios.\n\nA Performance Comparison of the Experiments\n\nAn analysis of the historical, experimental, and random algorithms’ performance during the saturated scenario (Figure 28) shows that the overall, the historical and experimental algorithms share the same performance graph except during the cold-start\nstate where the historical algorithm is required to perform operations locally until training has been completed. Operations 1, 50, and 100 show the cold-start states and it can be clearly seen that the experimental algorithm can quickly change to the new operation and select a beneficial surrogate while the historical algorithm requires training. The random algorithm can be seen selecting surrogates at random within the pool of the 5 available surrogates.\n\n\n\nFigure 28 – A Performance Comparison of the Historical, Random, and Experimental Algorithms in the Saturated Scenario\n\nAn analysis of the historical, experimental, and random algorithms’ performance during the slowly churning scenario shows that overall, the historical and experimental algorithms share the same performance graph (Figure 29) except during the cold-start state. The slowly churning scenario starts with no surrogates available and surrogates come online one at a time until all surrogates are available for use. Again, at operations 3, 53, and 103, the historical algorithm is required to perform operations locally until training has been completed while the experimental algorithm is quickly able to utilize\nthe newly arrived surrogate. The random algorithm, favoring remote execution also immediately utilizes the new surrogate by default since it is the only surrogate available. As seen previously, at operation 13, a new surrogate arrives and again, the experimental algorithm is able to recognize that this surrogate is more powerful and utilizes it immediately while the historical algorithm trains the surrogate. At this point, the random algorithm has 2 surrogates to choose from and oscillates between them. As more surrogates become available, both the historical and experimental algorithms do not change the selected surrogate while the random algorithm randomly selects surrogates from the slowly growing pool of available surrogates. This scenario repeats for the contrast and grayscale operations that start at operation 50 and 100, respectively.\n\n\n\nFigure 29 – A Performance Comparison of the Historical, Random, and Experimental Algorithms in the Slowly Churning Scenario\n\nAn analysis of the historical, experimental, and random algorithms’ performance during the quickly churning scenario shows a sharp deviation (Figure 30) between the\nhistorical algorithm and the experimental algorithm. In this scenario, surrogates arrive, leave the environment, and do not retain their training history between connections (to simulate every connection being a new device encounter). This is evident by the frequent spikes in the historical algorithm’s performance compared to the experimental algorithm while the historical algorithm is training the newly arrived surrogates. In this scenario, the blind choosing of surrogates from a limited surrogate pool is often beneficial. This can be seen by the random algorithm closely following the experimental algorithm when only a few surrogates are available and the random chance picks a favorable surrogate.\n\n\n\n**Figure 30 – A Performance Comparison of the Historical, Random, and Experimental Algorithms in the Quickly Churning Scenario**\n\n**Scheduling Algorithm Overhead**\n\nThe historical scheduling algorithm utilized simple linear regression to predict the execution time of operation based upon past observations. This required each surrogate to store data about each operation a surrogate could perform and required each connected surrogate to maintain a historical dataset for each operation. This scheduling algorithm\nscaled $O(n)$ and required the linear regression prediction method to be invoked for each node to determine the most beneficial surrogate for the current operation and image size. In addition to this overhead, jScavenger will request each new surrogate to perform the required operation on both a full-size image and a thumbnail image upon arrival. This additional training overhead occurs on a background thread. In the saturated scenario, the additional training overhead was 15 individual training sessions, the slowly churning scenario required 15 unique training sessions, and the quickly churning scenario required 64 training sessions.\n\nThe experimental scheduling algorithm utilized the surrogate speed rating and the approximate number of bytecode contained within an operation as a heuristic to choose a surrogate. The operational overhead for this algorithm, once the speed rating and the bytecode count was determined, was minimal. The surrogates were stored in a sorted list ranked by the anticipated speed of the operation. Retrieving a beneficial surrogate from the list was an $O(1)$ operation.\n\nThe random scheduling algorithm generated a random number between 1 and the size of the currently connected surrogate list. The scheduler simply utilized the surrogate associated with the random number that was generated. This yielded an ultra-low overhead scheduling algorithm that could be implemented as $O(1)$ if implemented in a data structure that supported direct access. In this research, the algorithm scaled $O(n)$ because the surrogates were stored in a linked list which does not support direct access.\n\n**Summary of Results**\n\nThree experiments were conducted for this research, one for each of the scheduling algorithms used to select a surrogate to remotely execute image-processing operations. The scheduling algorithms consisted of a historical algorithm, an\nexperimental algorithm, and random algorithm. Each experiment consisted of the same 4 operational scenarios: disconnected, saturated, slowly churning, and quickly churning. Each operational scenario executed 300 operations consisting of sharpening an image, adjusting the contrast of an image, and converting an image to grayscale.\n\nIt was found that the historical scheduling algorithm required 8.25 hours to execute the 1,200 operations across all 4 operational scenarios with 93 individual training sessions. The experimental scheduling algorithm required 7.38 hours to complete all 1,200 operations across the 4 operational scenarios with no training required. The random scheduling algorithm required 10.2 hours to complete the 1,200 operations contained in the operational scenarios with no training overhead.\n\nIt was found that the historical and experimental algorithms performed consistently when the environment was static or slowly changing differing only by the number of training sessions required. When the frequency of change increased, the performance of the historical and experimental algorithms quickly diverged. This was because the training requirement of the historical algorithm prevented the use of newly arrived surrogates until training had been completed. The experimental algorithm was shown to be able utilize beneficial surrogates immediately, without training, which allotted for the performance gain when the rate of change increased.\n\nAs expected, the random scheduler was the slowest of the three algorithms with one exception. The random algorithm achieved a faster execution time for the quickly churning scenario than the historical algorithm did for the same scenario. The random scheduling algorithm beat the historical algorithm by 31 minutes. This reinforces the\nbenefits of cyber foraging and suggests that even unguided offloading in an unknown environment may be beneficial.\n\nOverall, the experimental scheduling algorithm presented in this research outperformed both the historical and random scheduling algorithms for all scenarios (excluding the disconnected scenario). This achieved the goal of this research of increasing the performance of cyber foraging application by decreasing the overall execution time of a cyber foraging application.\nChapter 5\nConclusions, Implications, Recommendations, and Summary\n\nConclusions\n\nThis research has shown that a heuristic-based scheduling algorithm can increase the performance of a cyber foraging application by decreasing the application’s runtime. The success of the experimental algorithm was attributed to the algorithm’s ability to utilize beneficial surrogates faster, rather than delaying remote execution while the surrogate was trained.\n\nThree experiments were conducted as a part of this research. The first experiment investigated the use of a historical scheduling algorithm to offload operations for remote execution. The second experiment utilized the experimental scheduling algorithm, which utilized a heuristic-based scheduling algorithm to offload operations for remote execution. The third experiment utilized a random scheduling algorithm that randomly selected a surrogate from the list of available surrogates for use. The results of each experiment were then compared to derive the performance analysis.\n\nThe results of the historical experiment showed that the training overhead was directly related to the overall surrogate-churn. During the saturated test, 15 individual training sessions were required. Since all five surrogates were available for the duration of the test, 5 training sessions were required for each of the three operations conducted during the test. The slowly churning test also required 15 training sessions, as each of the surrogates were utilized during the duration of the test. The quickly churning scenario saw the greatest training overhead as 64 individual training sessions were required because surrogates frequently joined and left the network.\nThe random scheduler experiment showed that blindly offloading operations to surrogates could be beneficial in scenarios where there are relatively few surrogates. In the saturated scenario, where all 5 surrogates were available, the random scheduler produced the longest execution time of all the scheduling algorithms. This can be attributed to the scheduler picking surrogates that were better than local execution, but far slower than the most beneficial surrogate available. On the other end of the spectrum, in the quickly churning scenario, where there were relatively few surrogates to choose from, the random selection of surrogates produced a faster execution time than the historical scheduling algorithm. This can be attributed to the high probability of selecting a beneficial surrogate from the small pool of available surrogates.\n\nThe results of the experimental experiment showed that a heuristic-based scheduling algorithm was able to decrease the execution time of an application. The experimental scheduling algorithm achieved the fastest overall application execution times of all the scheduling algorithms, beating the historical algorithm by 0.87 of an hour (10.5%) and the random algorithm by 2.82 hours (28%).\n\n**Implications**\n\nThis research provided an approach to surrogate selection during the cold-start state that fast tracks the utilization of new surrogates or new operations on existing surrogates when there was a lack of past performance data. The experimental algorithm has demonstrated the ability to eliminate the cold-start state in historically based scheduling algorithms. This suggests that the experimental algorithm may be implemented without the need of a historical component, thus eliminating the overhead of storing performance data and performing prediction calculations.\n**Recommendations**\n\nThe goal of the research was met by the experimental algorithm; however, there are some areas of research could be pursued. Kristensen (2010) utilized the NBench2 benchmark suite to produce surrogate strengths, but the benchmark was a heavyweight process and required about 10 minutes to execute per device. The heuristic utilized in this research was lightweight and reduced the overhead required by leveraging the execution of the software itself to generate the data. Additional research into determining the minimum amount of data required to create a useful heuristic for use in the offloading of operations could further reduce the effort required to generate the heuristics.\n\nThe differences between CPU architecture and instruction execution speed could also be investigated to determine the architectural impact native code execution has upon the heuristic. Kristensen and Bouvin (2010) observed that the different CPU architectures influenced the operation weights in their heuristic. The operation weights for the PowerPC CPU architecture were almost three times as high when compared to the Intel architecture for the same operation. Additional research into how the architectural difference can be incorporated into a heuristic will allow for a smoother application of the heuristic in a heterogeneous environment.\n\nThis research focused heavily upon CPU performance; however, the incorporation of other subsystems could provide a more accurate heuristic. The performance of Hadoop nodes in a cloud computing environment incorporated the use of disk I/O performance, memory performance, and network performance in the overall evaluation of node performance (Lin & Liu, 2013). The authors’ state that this was required due to the diversity of individual nodes in the Hadoop cluster diverging over time, due to hardware\nfailures and upgrades. The incorporation of additional heuristics could improve the overall performance estimate, especially if the operations rely heavily upon a subsystem that is not currently accounted for in the general heuristic.\n\nIn an effort to optimize the scheduling of tasks in a cloud environment, the task requirements and server capabilities are required so that tasks can be paired with the most suitable server (Gupta, Fritz, Price, Hoover, De Kleer, & Witteveen, 2013). Gupta, et al. (2013) utilized offline training to build a historical dataset of server and job performance for use in scheduling because no method currently exists to estimate server performance from hardware specifications. The use of a Bayesian estimator to produce a performance heuristic for each surrogate based upon hardware specifications could potentially provide performance heuristics for use in task scheduling.\n\n**Summary**\n\nMobile devices due to their size, weight, and power constraints typically lag behind stationary desktop workstations where processing power, memory, and storage capacity are concerned. The cyber foraging paradigm enables mobile devices to perform beyond their means by offloading code for remote execution. By remotely executing code, an application can conserve memory and battery power by allowing surrogate machines to expend the resources rather than requiring the mobile device itself to expend the precious resources. The remote execution of code may also allow for the overall execution time of the process to be shortened or the fidelity of the result to be increased due to the utilization of high-performance computers rather than the resource poor mobile device.\nA barrier to making offloading decisions in a cyber foraging system centers on obtaining enough information to make informed remote execution decisions. Given ample time and processing power, an execution scheduler can enumerate all available surrogates to determine the optimum surrogate to utilize in a given situation; however, in a highly interactive environment, the time required to make such a determination may be greater than what the end-user is willing to accept. The price may also be higher in terms of the processing power and the battery power expended to make the offloading decision than would be gained by remotely executing the operation. Compounding this issue is the cold-start problem, which potentially delays the availability of a newly arrived surrogate because the system does not have enough information available to rank the surrogate for remote execution scheduling.\n\nThis research achieved the goal of utilizing metrics obtained from the run-time profiling of a Java program to decrease the run-time of a cyber foraging application. This was accomplished by scheduling beneficial offloading decisions during the cold-start state. The utilization of run-time metrics from the applications themselves provided a heuristic that does not require a-priori training, design-time information from the developer, or training effort from the end-user in order for the system to make informed offloading decisions.\n\nThe methodology utilized to obtain the metrics for the heuristic was based upon the speed that a surrogate demonstrated it could execute Java bytecode instructions and the average number of instructions contained within an operation. To obtain the speed rating for each surrogate, the surrogate client application was profiled to obtain the average number of instructions that were expected to be executed during the initialization\nof the client. The operations were profiled by generating a control flow graph for the operation and calculating the average number of instruction that could potentially be executed by the operation. The surrogate selection process calculates the potential execution speed for the operation by dividing the expected number of instructions in the operation by the speed of the surrogate.\n\nThree experiments were conducted, one for each of the scheduling algorithms used to select a surrogate for remote execution. The scheduling algorithms consisted of a historical algorithm, an experimental algorithm, and random algorithm. Each experiment consisted of the same 4 operational scenarios: disconnected, saturated, slowly churning, and quickly churning.\n\nThe disconnected operation scenario tested the system in an environment where there are no surrogates available. The saturated environment scenario tested the system in an over-provisioned environment where all 5 surrogates were available. The slowly churning environment scenario exercised the system in an environment where there were initially no surrogates and surrogates were slowly added to the system until all five surrogates were available for use. The quickly churning environment scenario exercised the system in an environment where initially no surrogates were available. Surrogates were then simultaneously added and removed from the system after every few operations. Each operational scenario executed 300 operations consisting of sharpening an image, adjusting the contrast of an image, and converting an image to grayscale.\n\nIt was found that the historical scheduling algorithm required 8.25 hours to execute the 1,200 operations across all 4 operational scenarios with 93 individual training sessions. The experimental scheduling algorithm required 7.38 hours to complete all\n1,200 operations across the 4 operational scenarios with no training required. The random scheduling algorithm required 10.2 hours to complete the 1,200 operations contained in the operational scenarios with no training overhead.\n\nOverall, the experimental scheduling algorithm presented in this research outperformed the historical scheduling algorithm by 10.5% and the random scheduling algorithm by 28%. This achieved the research goal by decreasing the overall execution time of a cyber foraging application.\nAppendices\nAppendix A: Sample Java Program\n\nThe sample Java program used in generating the sample CFG.\n\n```java\npublic class SimpleJavaProgram {\n public static void main(String[] args) {\n int a = 5;\n int b = 10;\n System.out.println(\"A = \"+ a);\n System.out.println(\"B = \"+ b);\n if (a > 5) {\n a++;\n b--;\n } else {\n a--;\n b++;\n }\n System.out.println(\"A = \"+ a);\n System.out.println(\"B = \"+ b);\n }\n}\n```\nAppendix B: Sample Java Program – Bytecode Representation\n\nCommand line used to generate and capture the output was:\n\njavap -v SimpleJavaProgram.class > output.txt\n\nThe Java version used to generate this output: java version \"1.7.0_17\"\n\nNote: This output has been altered. The comments have been removed from the output due to space and formatting considerations.\n\n--Start Listing--\n 0: icnst_5\n 1: istore_1\n 2: bipush 10\n 4: istore_2\n 5: getstatic #16\n 8: new #22\n 11: dup\n 12: ldc #24\n 14: invokespecial #26\n 17: iload_1\n 18: invokevirtual #29\n 21: invokevirtual #33\n 24: invokevirtual #37\n 27: getstatic #16\n 30: new #22\n 33: dup\n 34: ldc #42\n 36: invokespecial #26\n 39: iload_2\n 40: invokevirtual #29\n 43: invokevirtual #33\n 46: invokevirtual #37\n 49: iload_1\n 50: icnst_5\n 51: if_icmple 63\n 54: iinc 1, 1\n 57: iinc 2, -1\n 60: goto 69\n 63: iinc 1, -1\n 66: iinc 2, 1\n 69: getstatic #16\n 72: new #22\n 75: dup\n 76: ldc #24\n 78: invokespecial #26\n 81: iload_1\n 82: invokevirtual #29\n 85: invokevirtual #33\n 88: invokevirtual #37\n 91: getstatic #16\n 94: new #22\n97: dup\n98: ldc #42\n100: invokespecial #26\n103: iload_2\n104: invokevirtual #29\n107: invokevirtual #33\n110: invokevirtual #37\n113: return\n--End Listing--\nAppendix C: Sample Execution Log File Data\n\nBelow is an excerpt from the execution log. The header row and empty lines between entries have been added to increase readability.\n\n```\nsequence number~record type~record data\n1~1~<request><requestID>1</requestID><requestType>RPC</requestType><operationName>ImageLib.Contrast</operationName><fileName>dog.png</fileName><parameters><parameter><parameterName>imageBytes</parameterName><parameterDirection>IN</parameterDirection><parameterDataType>byte[]</parameterDataType><parameterValue></parameterValue></parameter></parameters></request>\n\n2~2~<response><responseID>1</responseID><operationName>ImageLib.Contrast</operationName><executionTime>32421</executionTime><errorCode>0</errorCode><errorDescription></errorDescription><parameters><parameter><parameterName>RETURN_VALUE</parameterName><parameterDirection>OUT</parameterDirection><parameterDataType>byte[]</parameterDataType><parameterValue>X62IBNhchbxBwbGhVwc==</parameterValue></parameter></parameters>\n\n3~3~ImageLib.Contrast~dog.png~6209174~surrogate-2~785~421~surrogate-1;surrogate-2;surrogate-3;surrogate-4;surrogate-5~cold-start;online;offline;online;online\n\n4~1~<request><requestID>2</requestID><requestType>RPC</requestType><operationName>ImageLib.Contrast</operationName><fileName>dog.thumb.png</fileName><parameters><parameter><parameterName>imageBytes</parameterName><parameterDirection>IN</parameterDirection><parameterDataType>byte[]</parameterDataType><parameterValue></parameterValue></parameter></parameters></request>\n\n5~2~<response><responseID>2</responseID><operationName>ImageLib.Contrast</operationName><executionTime>421</executionTime><errorCode>0</errorCode><errorDescription></errorDescription><parameters><parameter><parameterName>RETURN_VALUE</parameterName><parameterDirection>OUT</parameterDirection><parameterDataType>byte[]</parameterDataType><parameterValue>X62IBNhchbxBwbGhVwc==</parameterValue></parameter></parameters>\n\n6~3~ImageLib.Contrast~dog.png~7194~surrogate-2~285~121~surrogate-1;surrogate-2;surrogate-3;surrogate-4;surrogate-5~cold-start;online;offline;online;online\n```\nAppendix D: Sample Driver File – Saturated Scenario\n\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE, s-2=ONLINE, s-3=ONLINE, s-4=ONLINE, s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC SHARPEN s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\n### Appendix E: Sample Driver File – Slowly Churn Scenario\n\n<table>\n<thead>\n<tr>\n<th>RPC SHARPEN s</th>\n<th>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s</td>\n<td>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n<tr>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n<td>RPC SHARPEN s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;</td>\n</tr>\n</tbody>\n</table>\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nAppendix F: Sample Driver File – Quickly Churning Scenario\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</th>\n<th>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</th>\n<th>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</th>\n<th>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</th>\n<th>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</th>\n<th>1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RPC SHARPEN</td>\n<td>s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n<td>s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n<td>s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n<td>s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n<td>s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n<td>s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;</td>\n</tr>\n</tbody>\n</table>\n\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=ONLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=ONLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=ONLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=ONLINE, s-2=OFFLINE, s-3=ONLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=ONLINE, s-2=OFFLINE, s-3=ONLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=ONLINE, s-2=OFFLINE, s-3=ONLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=ONLINE, s-2=OFFLINE, s-3=ONLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=ONLINE, s-2=OFFLINE, s-3=ONLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=ONLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=ONLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC SHARPEN s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=ONLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC CONTRAST s-1=OFFLINE, s-2=OFFLINE, s-3=OFFLINE, s-4=OFFLINE, s-5=OFFLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=OFFLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=OFFLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=ONLINE,s-2=ONLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=ONLINE,s-2=ONLINE,s-3=OFFLINE,s-4=ONLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=ONLINE,s-5=OFFLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\nRPC GRAYSCALE s-1=OFFLINE,s-2=OFFLINE,s-3=ONLINE,s-4=OFFLINE,s-5=ONLINE;\n<p>| | | | | |</p>\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>2</td>\n<td>3</td>\n<td>4</td>\n<td>5</td>\n</tr>\n<tr>\n<td>s-1</td>\n<td>s-2</td>\n<td>s-3</td>\n<td>s-4</td>\n<td>s-5</td>\n</tr>\n<tr>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n</tr>\n<tr>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n</tr>\n<tr>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n</tr>\n<tr>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n<td>ONLINE</td>\n</tr>\n<tr>\n<td>OFFLINE</td>\n<td>ONLINE</td>\n<td>OFFLINE</td>\n<td>ONLINE</td>\n<td>OFFLINE</td>\n</tr>\n<tr>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n</tr>\n<tr>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n</tr>\n<tr>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n</tr>\n<tr>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n</tr>\n<tr>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n<td>OFFLINE</td>\n</tr>\n</tbody>\n</table>\nReferences\n\n\n"}}},{"rowIdx":52,"cells":{"id":{"kind":"string","value":"baa34f5dd565c57d7a5877cf0663cf8e540a0824"},"text":{"kind":"string","value":"This document describes the use of version 12.2.1.0 plug-ins provided for proxying requests from web servers to Oracle WebLogic Server. This document is intended mainly for system administrators who manage the WebLogic Server application platform and its various subsystems.\n### Contents\n\nPreface ............................................................................................................................................................ vii \nDocumentation Accessibility .................................................................................................................... vii \nConventions................................................................................................................................................ vii \n\n1 Overview of Oracle WebLogic Server Proxy Plug-In \n1.1 What are Oracle WebLogic Server Proxy Plug-Ins? ................................................................ 1-1 \n1.1.1 Connection Pooling and Keep-Alive..................................................................................... 1-1 \n1.1.2 Proxying Requests................................................................................................................ 1-2 \n1.2 Availability of Oracle WebLogic Server Proxy Plug-In ............................................................. 1-2 \n1.3 Upgrading from 1.0 Plug-Ins .......................................................................................................... 1-2 \n1.3.1 Upgrade Instructions ............................................................................................................ 1-3 \n1.3.2 Considerations for Upgrading From Oracle WebLogic Server Proxy Plug-Ins \n Version 1.0 to 12c (12.2.1)........................................................................................................... 1-3 \n1.4 Features of the Version 12.2.1 Plug-Ins....................................................................................... 1-4 \n1.4.1 Oracle WebLogic Server Proxy Monitoring ....................................................................... 1-4 \n1.4.2 Support for Multi-tenancy and Partitions .......................................................................... 1-4 \n1.4.3 SSL Support for IPlanet Web Server .................................................................................. 1-4 \n1.4.4 Documentation for Using Plug-ins with IIS 7.5 ............................................................... 1-4 \n1.5 Support and Patching...................................................................................................................... 1-4 \n\n2 Configuring the Plug-In for Oracle HTTP Server \n2.1 Oracle HTTP Server Support Note................................................................................................. 2-1 \n2.2 Preparing for Configuring the Oracle WebLogic Server Proxy Plug-In.................................... 2-1 \n 2.2.1 Setting the WebLogic Plug-In Enabled Parameter ......................................................... 2-2 \n2.3 Configuring the Oracle WebLogic Server Proxy Plug-In Using Fusion Middleware \n Control .............................................................................................................................................. 2-3 \n 2.3.1 Task 1: Navigate to the mod_wl_ohs Configuration Page........................................... 2-3 \n 2.3.2 Task 2: Specify the Configuration Settings.................................................................... 2-6 \n 2.3.3 Task 3: Configure Expression Overrides or Location Overrides (Optional) .......... 2-7 \n 2.3.4 Task 4: Apply Your Changes ....................................................................................... 2-8 \n 2.3.5 Using the Search Function ......................................................................................... 2-8 \n 2.3.6 Using the AutoFill Function ...................................................................................... 2-8\n2.4 Configuring the Oracle WebLogic Server Proxy Plug-In Manually ........................................ 2-9\n 2.4.1 Examples of <IfModule weblogic_module> Element Configurations................................. 2-9\n 2.5 Understanding Oracle WebLogic Server Proxy Plug-In Performance Metrics .......................... 2-12\n 2.5.1 Configuring DMS Metrics for Oracle HTTP Server Proxy Plug-in .................................. 2-12\n 2.5.2 Viewing Performance Metrics for Oracle HTTP Server Proxy Plug-in ............................. 2-12\n 2.5.3 DMS State Metrics ........................................................................................................... 2-13\n 2.5.4 DMS Event Metrics .......................................................................................................... 2-14\n 2.5.5 DMS PhaseEvent Metrics ................................................................................................. 2-16\n 2.6 Deprecated Directives for Oracle HTTP Server ....................................................................... 2-16\n 2.7 Troubleshooting Oracle WebLogic Server Proxy Plug-In Implementations ............................ 2-17\n 2.7.1 WLS Session Issues ............................................................................................................ 2-17\n 2.7.2 CONNECTION_REFUSED Errors ...................................................................................... 2-17\n 2.7.3 NO_RESOURCES Errors .................................................................................................... 2-18\n 2.7.4 Changing the Oracle WebLogic Server Keystore Causes Unexpected Behavior ................. 2-18\n\n3 Configuring the Plug-In for Apache HTTP Server\n 3.1 Apache HTTP Server Support Note .......................................................................................... 3-1\n 3.2 Install the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server ........................... 3-1\n 3.2.1 Installation Prerequisites ................................................................................................ 3-1\n 3.2.2 Installing the Apache HTTP Server Plug-In ..................................................................... 3-2\n 3.3 Configure the Apache HTTP Server Plug-In ............................................................................ 3-3\n 3.3.1 Configuring the httpd.conf File ....................................................................................... 3-4\n 3.3.2 Placing WebLogic Properties Inside Location or VirtualHost Blocks ............................. 3-7\n 3.3.3 Example: Configuring the Apache Plug-In ....................................................................... 3-7\n 3.3.4 Including a weblogic.conf File in the httpd.conf File ...................................................... 3-8\n 3.4 Understanding DMS Metrics for Apache HTTP Server Plug-in .............................................. 3-11\n 3.4.1 Configuring Metrics DMS Metrics for Apache HTTP Server Plug-in .............................. 3-11\n 3.4.2 Viewing Performance Metrics for Apache HTTP Server Plug-in .................................... 3-12\n 3.5 Deprecated Directives for Apache HTTP Server ...................................................................... 3-12\n\n4 Configuring the Plug-In for iPlanet Web Server\n 4.1 Overview of the Oracle WebLogic Server Proxy Plug-In for iPlanet ....................................... 4-1\n 4.2 Installing and Configuring the Plug-In for iPlanet ................................................................ 4-1\n 4.2.1 Installation Prerequisites ................................................................................................ 4-2\n 4.2.2 Installing the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server ............... 4-3\n 4.2.3 Configuring the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server .......... 4-3\n 4.2.4 Example: Configuring the iPlanet Plug-in ...................................................................... 4-6\n 4.2.5 Guidelines for Modifying the obj.conf File ..................................................................... 4-6\n 4.2.6 Sample obj.conf File (Not Using a WebLogic Cluster) .................................................. 4-7\n 4.2.7 Sample obj.conf File (Using a WebLogic Cluster) ......................................................... 4-8\n 4.3 Deprecated Directives for iPlanet Web Server ........................................................................ 4-9\n5 Configuring the Plug-In for Microsoft IIS Web Server\n\n5.1 Working with the Microsoft IIS 7.0 Plug-In\n5.1.1 Installing and Configuring the Microsoft IIS 7.0 Plug-In\n5.1.2 Serving Static Files from the Web Server\n5.1.3 Using Wildcard Application Mappings to Proxy by Path\n5.1.4 Proxying Requests from Multiple Virtual Web Sites to WebLogic Server\n5.1.5 Creating ACLs Through IIS 7.0\n5.1.6 Testing the Installation\n\n5.2 Working with the Microsoft IIS 7.5 Plug-In\n5.2.1 Installing and Configuring the Microsoft IIS 7.5 Plug-In\n5.2.2 Serving Static Files with IIS 7.5\n5.2.3 Serving Static Files and Dynamic Content From the Same Request with IIS 7.5\n\n6 Configuring Security\n\n6.1 Using SSL with Plug-Ins\n6.1.1 Configuring Libraries for SSL\n6.1.2 Configuring a Plug-In for One-Way SSL\n6.1.3 Configuring Two-Way SSL Between the Plug-In and Oracle WebLogic Server\n\n6.2 Configuring SSL with the Plug-In for iPlanet Web Server\n\n6.3 Configuring Perimeter Authentication\n\n7 Common Configuration Tasks\n\n7.1 Configuring IPv6 With Plug-Ins\n\n7.2 Understanding Connection Errors and Clustering Failover\n7.2.1 Possible Causes of Connection Failures\n7.2.2 Tips for Reducing CONNECTION_REFUSED Errors\n7.2.3 Failover with a Single, Non-Clustered WebLogic Server\n7.2.4 The Dynamic Server List\n7.2.5 Failover, Cookies, and HTTP Sessions\n7.2.6 Failover Behavior When Using Firewalls and Load Directors\n\n7.3 Tuning Oracle HTTP Server and Apache HTTP Server for High Throughput for WebSocket Upgrade Requests\n\n7.4 Working with Partitions\n7.4.1 Adding a Partition\n7.4.2 Modifying a Partition and Partition Migration\n7.4.3 Configuring SSL Between the Web Server and Oracle WebLogic Server\n7.4.4 Dynamic Discovery of Cluster Changes\n\n8 Parameters for Web Server Plug-Ins\n\n8.1 General Parameters for Web Server Plug-Ins\n8.1.1 ConnectRetrySecs\n8.1.2 ConnectTimeoutSecs\n8.1.3 Debug ................................................................................................................................. 8-3\n8.1.4 DebugConfigInfo..................................................................................................................... 8-4\n8.1.5 DefaultFileName ....................................................................................................................... 8-4\n8.1.6 DynamicServerList .................................................................................................................. 8-4\n8.1.7 ErrorPage ................................................................................................................................. 8-5\n8.1.8 FileCaching .............................................................................................................................. 8-5\n8.1.9 Idempotent ............................................................................................................................... 8-6\n8.1.10 KeepAliveEnabled .................................................................................................................... 8-6\n8.1.11 KeepAliveSecs .......................................................................................................................... 8-6\n8.1.12 MatchExpression ...................................................................................................................... 8-6\n8.1.13 MaxPostSize ............................................................................................................................. 8-7\n8.1.14 MaxSkipTime ............................................................................................................................ 8-8\n8.1.15 PathPrepend ............................................................................................................................. 8-8\n8.1.16 PathTrim .................................................................................................................................... 8-8\n8.1.17 QueryFromRequest ................................................................................................................... 8-9\n8.1.18 WebLogicCluster ..................................................................................................................... 8-9\n8.1.19 WebLogicHost .......................................................................................................................... 8-10\n8.1.20 WebLogicPort ............................................................................................................................ 8-10\n8.1.21 WLCookieName ....................................................................................................................... 8-10\n8.1.22 WLDNSRefreshInterval ........................................................................................................... 8-10\n8.1.23 WLExcludePathOrMimeType ..................................................................................................... 8-10\n8.1.24 WLFlushChunks ......................................................................................................................... 8-11\n8.1.25 WLForwardUriUnparsed .......................................................................................................... 8-11\n8.1.26 WLIOTimeoutSecs ..................................................................................................................... 8-11\n8.1.27 WLLocalIP .................................................................................................................................. 8-11\n8.1.28 WLLlogfile ................................................................................................................................ 8-11\n8.1.29 WLMaxWebSocketClients ....................................................................................................... 8-12\n8.1.30 WLProxyPassThrough ............................................................................................................. 8-12\n8.1.31 WLProxySSL ............................................................................................................................. 8-12\n8.1.32 WLProxySSLPassThrough ......................................................................................................... 8-12\n8.1.33 WLRetryAfterDroppedConnection ......................................................................................... 8-13\n8.1.34 WLSendHdrSeparately ............................................................................................................. 8-13\n8.1.35 WLServerInitiatedFailover ....................................................................................................... 8-13\n8.1.36 WLSocketTimeoutSecs .............................................................................................................. 8-13\n8.1.37 WLSRequest ............................................................................................................................ 8-14\n8.1.38 WLTempDir ............................................................................................................................. 8-14\n\n8.2 SSL Parameters for Web Server Plug-Ins .................................................................................... 8-14\n8.2.1 SecureProxy ............................................................................................................................. 8-15\n8.2.2 WebLogicSSLVersion .............................................................................................................. 8-15\n8.2.3 WLSSLWallet ............................................................................................................................ 8-15\n\n8.3 Location of POST Data Files ..................................................................................................... 8-16\nThis preface describes the document accessibility features and conventions used in this guide—Using Oracle WebLogic Server Proxy Plug-Ins 12.2.1.1.\n\nDocumentation Accessibility\n\nFor information about Oracle's commitment to accessibility, visit the Oracle Accessibility Program website at http://www.oracle.com/pls/topic/lookup?ctx=acc&id=docacc.\n\nAccess to Oracle Support\n\nOracle customers that have purchased support have access to electronic support through My Oracle Support. For information, visit http://www.oracle.com/pls/topic/lookup?ctx=acc&id=info or visit http://www.oracle.com/pls/topic/lookup?ctx=acc&id=trs if you are hearing impaired.\n\nConventions\n\nThe following text conventions are used in this document:\n\n<table>\n<thead>\n<tr>\n<th>Convention</th>\n<th>Meaning</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>boldface</strong></td>\n<td>Boldface type indicates graphical user interface elements associated with an action, or terms defined in text or the glossary.</td>\n</tr>\n<tr>\n<td><em>italic</em></td>\n<td>Italic type indicates book titles, emphasis, or placeholder variables for which you supply particular values.</td>\n</tr>\n<tr>\n<td><code>monospace</code></td>\n<td>Monospace type indicates commands within a paragraph, URLs, code in examples, text that appears on the screen, or text that you enter.</td>\n</tr>\n</tbody>\n</table>\nThis chapter describes the plug-ins provided by Oracle for use with WebLogic Server:\n\n- What are Oracle WebLogic Server Proxy Plug-Ins?\n- Availability of Oracle WebLogic Server Proxy Plug-In\n- Upgrading from 1.0 Plug-Ins\n- Features of the Version 12.2.1 Plug-Ins\n- Support and Patching\n\n### 1.1 What are Oracle WebLogic Server Proxy Plug-Ins?\n\nWeb server plug-ins allow requests to be proxied from Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, or Microsoft Internet Information Server (IIS) to Oracle WebLogic Server. In this way, plug-ins enable the HTTP server to communicate with applications deployed on the WebLogic Server.\n\nThe plug-in enhances an HTTP server installation by allowing Oracle WebLogic Server to handle requests that require dynamic functionality. In other words, you typically use a plug-in where the HTTP server serves static pages such as HTML pages, while Oracle WebLogic Server serves dynamic pages such as HTTP Servlets and Java Server Pages (JSPs).\n\nOracle WebLogic Server may be operating in a different process, possibly on a different host. To the end user—the browser—the HTTP requests delegated to Oracle WebLogic Server still appear to be coming from the HTTP server.\n\nIn addition, the HTTP-tunneling facility of the WebLogic client/server protocol also operates through the plug-in, providing access to all Oracle WebLogic Server services.\n\n#### 1.1.1 Connection Pooling and Keep-Alive\n\nThe plug-ins improve performance using a pool of connections from the plug-in to Oracle WebLogic Server. The plug-in implements HTTP 1.1 keep-alive connections between the plug-in and Oracle WebLogic Server by reusing the same connection for subsequent requests from the same plug-ins. If the connection is inactive for more than 20 seconds, (or a user-defined amount of time), the connection is closed. For more information, see `KeepAliveEnabled`.\n\n---\n\n**Note:**\n\nThe web server manages client connections.\n1.1.2 Proxying Requests\n\nThe plug-in proxies requests to Oracle WebLogic Server based on a configuration that you specify.\n\n- You can proxy requests based on the URL of the request or a portion of the URL. This is called proxying by path.\n- You can also proxy a request based on the MIME type of the requested file, which is called proxying by file extension.\n\nYou can also enable both methods. If you enable both methods and a request matches both criteria, the request is proxied by path.\n\nYou can also specify additional parameters for each of these types of requests that define additional behavior of the plug-in.\n\n1.2 Availability of Oracle WebLogic Server Proxy Plug-In\n\nVersion 12.2.1 plug-ins are available for the following web servers:\n\n<table>\n<thead>\n<tr>\n<th>Web Server</th>\n<th>Plug-In Availability</th>\n<th>More Information</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Oracle HTTP Server 12c</td>\n<td>The plug-in is included in the Oracle HTTP Server installation. For information about configuring this plug-in, see Configuring the Plug-In for Oracle HTTP Server.</td>\n<td>See Configuring the Plug-In for Oracle HTTP Server.</td>\n</tr>\n</tbody>\n</table>\n| Oracle iPlanet Web Server (7.0.9 and later releases) | The plug-ins are available for download on the My Oracle Support (http://support.oracle.com) and Software Delivery Cloud (http://edelivery.oracle.com) web sites as zip files containing the necessary binary and helper files. For example, the following directories are included in the mod_wl.so plug-in distribution. | For information about installing and configuring the plug-ins for Apache HTTP Server, Oracle iPlanet, and Microsoft IIS Web Servers, see the following: \n - Configuring the Plug-In for Apache HTTP Server \n - Configuring the Plug-In for iPlanet Web Server \n - Configuring the Plug-In for Microsoft IIS Web Server |\n| Apache HTTP Server 2.2.x | | |\n| Microsoft Internet Information Server (IIS) 7.0 and 7.5 | | |\n\n1.3 Upgrading from 1.0 Plug-Ins\n\nThe version 1.0 plug-ins are deprecated and are not guaranteed to be available for future versions of Oracle WebLogic Server. The version 12c (12.2.1.1.0) plug-ins are the recommended replacement.\nNote:\nFor Apache HTTP Server 1.3.x or 2.0.x, continue to use the version 1.0 plug-in.\n\nThis section contains the following information:\n\n- Upgrade Instructions\n- Considerations for Upgrading From Oracle WebLogic Server Proxy Plug-Ins Version 1.0 to 12c (12.2.1)\n\n### 1.3.1 Upgrade Instructions\n\nFor upgrading from 11g plug-ins to the Oracle WebLogic Server Proxy Plug-Ins 12c (12.2.1.1.0), use installation instructions included in the specific chapter for your web server, as listed in Table 1-2.\n\n<table>\n<thead>\n<tr>\n<th>To upgrade to the 12c (12.2.1.1.0) plug-ins for:</th>\n<th>See:</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Oracle HTTP Server</td>\n<td>Configuring the Plug-In for Oracle HTTP Server</td>\n</tr>\n<tr>\n<td>Apache HTTP Server</td>\n<td>Configuring the Plug-In for Apache HTTP Server</td>\n</tr>\n<tr>\n<td>iPlanet Web Server</td>\n<td>Configuring the Plug-In for iPlanet Web Server</td>\n</tr>\n<tr>\n<td>Microsoft IIS Web Server</td>\n<td>Configuring the Plug-In for Microsoft IIS Web Server</td>\n</tr>\n</tbody>\n</table>\n\n### 1.3.2 Considerations for Upgrading From Oracle WebLogic Server Proxy Plug-Ins Version 1.0 to 12c (12.2.1)\n\nThe version 12c (12.2.1) plug-ins are a superset of the version 1.0 plug-ins and support the existing features. However, when you upgrade, keep the following considerations in mind:\n\n- The list of supported platforms has changed. For more information, see the Oracle Fusion Middleware Supported System Configurations at:\n \n\n- Because the version 1.0 plug-ins supported both 40- and 128-bit encryption standards, the plug-in file names needed to identify which standard was supported. For example, mod_wl_22.so indicated 40-bit encryption and mod_wl128_22.so indicated 128-bit encryption; however, the version 12c (12.2.1) plug-ins support only 128-bit encryption, and the plug-in names are now simplified. For example, mod_wl.so is the only file name required.\n\nNote:\nIf you upgrade from the 1.0 plug-ins and had been using 128-bit encryption, you must change your configuration file to reflect the new naming convention. For example, you must change mod_wl128_22.so to mod_wl.so.\n1.4 Features of the Version 12.2.1 Plug-Ins\n\nThis section describes the additional features of the version 12c (12.2.1) plug-ins.\n\n- Oracle WebLogic Server Proxy Monitoring\n- Support for Multi-tenancy and Partitions\n- SSL Support for IPlanet Web Server\n- Documentation for Using Plug-ins with IIS 7.5\n\n1.4.1 Oracle WebLogic Server Proxy Monitoring\n\nThe current release adds support for monitoring the performance of the Oracle HTTP Server. The performance metrics are specific to the Oracle WebLogic Server Proxy Plug-In where a request is proxied to the backend WebLogic server. See Understanding Oracle WebLogic Server Proxy Plug-In Performance Metrics.\n\n1.4.2 Support for Multi-tenancy and Partitions\n\nIn the current release, Oracle WebLogic Server Proxy Plug-Ins can be made partition-aware. This plays a role in support of Oracle WebLogic Server MT (multi-tenancy). See Working with Partitions.\n\n1.4.3 SSL Support for IPlanet Web Server\n\nIn the current release, support has been added for using SSL with the iPlanet Web Server. See Configuring SSL with the Plug-In for iPlanet Web Server.\n\n1.4.4 Documentation for Using Plug-ins with IIS 7.5\n\nInstructions have been added to use Oracle WebLogic Server Proxy Plug-Ins with Microsoft IIS Web Server 7.5. See Working with the Microsoft IIS 7.5 Plug-In.\n\n1.5 Support and Patching\n\nWhen you encounter issues with a plug-in, always report the version of the plug-in you are using. You can find this information in the apache log or the plug-in debug log (if configured). The version information will look like this:\n\nWebLogic Server Plug-in version 12.2.1 <WLSPLUGINS_XXXX_XXXX_XXXXX.XXXX>\n\nNote:\n\nOn the Apache Web Server for Linux, You can also obtain the plugin version by issuing the following command:\n\n```\nstrings $(PLUGIN_HOME)/lib/mod_wl.so | grep -i wlsplugins\n```\n\nA patch for a plug-in typically will contain one or more shared objects to be replaced. Be sure to backup your original files as you replace them with those in the patch. Validate that the patch has been correctly updated by checking the version string in the logs.\nConfigure the Oracle WebLogic Server Proxy Plug-In, which is the plug-in for proxying requests from Oracle HTTP Server to Oracle WebLogic Server. The Oracle WebLogic Server Proxy Plug-In is included in the Oracle HTTP Server 12c (12.2.1.1.0) installation. You do not have to download and install it separately.\n\n**Note:**\nThe Oracle WebLogic Server Proxy Plug-In provides features that are identical to those of the plug-in for Apache HTTP Server.\n\nYou can configure the Oracle WebLogic Server Proxy Plug-In either by using Fusion Middleware Control or by editing the mod_wl_ohs.conf configuration file manually.\n\nThis chapter contains the following topics:\n\n- Oracle HTTP Server Support Note\n- Preparing for Configuring the Oracle WebLogic Server Proxy Plug-In\n- Configuring the Oracle WebLogic Server Proxy Plug-In Using Fusion Middleware Control\n- Configuring the Oracle WebLogic Server Proxy Plug-In Manually\n- Understanding Oracle WebLogic Server Proxy Plug-In Performance Metrics\n- Deprecated Directives for Oracle HTTP Server\n- Troubleshooting Oracle WebLogic Server Proxy Plug-In Implementations\n\n### 2.1 Oracle HTTP Server Support Note\n\nThe Oracle WebLogic Server Proxy Plug-In for Oracle HTTP Server is now able to front-end WebSocket applications.\n\n### 2.2 Preparing for Configuring the Oracle WebLogic Server Proxy Plug-In\n\nYou must complete some installation and verification tasks before configuring the Oracle WebLogic Server Proxy Plug-In.\n\n- Ensure that Oracle WebLogic Server has been installed, a domain has been created, and you can access the Oracle WebLogic Server administration console.\nHTTP Server and WebLogic Server can be installed either in same domain or in separate domains.\n\n- Verify that Fusion Middleware Control has been installed and you can access the Enterprise Manager Console. This is required to configure the Oracle WebLogic Server Proxy Plug-In by using the graphical interface provided by Fusion Middleware Control. The Fusion Middleware Control is available only for WebLogic managed domains.\n\n- To be able to test the configuration, ensure that the required Java applications are deployed to Oracle WebLogic Server—either to a single managed server or to a cluster—and are accessible.\n\n### 2.2.1 Setting the WebLogic Plug-In Enabled Parameter\n\nYou must set the WebLogic Plug-In Enabled parameter if the version of the Oracle WebLogic Server instances in the back end is 10.3.4 (or later) release.\n\n1. Log in to the Oracle WebLogic Server administration console.\n2. In the Domain Structure pane, expand the Environment node.\n - If the server instances to which you want to proxy requests from Oracle HTTP Server are in a cluster, select Clusters.\n - Otherwise, select Servers.\n3. Select the server or cluster to which you want to proxy requests from Oracle HTTP Server.\n4. Select WebLogic Server drop down menu, then Administration, then General Settings.\n \n The Configuration: General tab is displayed.\n5. Scroll down to the Advanced section, expand it, and select Yes from the WebLogic Plug-In Enabled drop-down list.\n \n Yes must be selected if the WebLogic Plug-ins are used with the WebLogic Server. For more information, see Understanding the WebLogic Plug-In Enabled Parameter.\n6. If you selected Servers in step 2, repeat steps 3 and 4 for the other servers to which you want to proxy requests from Oracle HTTP Servers.\n7. Click Save.\n\nFor the change to take effect, you must restart the server instances.\n\n### 2.2.1.1 Understanding the WebLogic Plug-In Enabled Parameter\n\nThe WebLogic Plug-In Enabled drop-down list contains these values:\n\n- **Yes**—Yes must be selected if the WebLogic Plug-ins are used with the WebLogic Server. When set to Yes on the server, it specifies that this server uses the proprietary WL-Proxy-Client-IP header, which is recommended if the server instance will receive requests from a proxy plug-in.\n \n When set to Yes on the cluster, it specifies that the cluster will receive requests from a proxy plug-in or HttpClusterServlet. A call to getRemoteAddr will\nreturn the address of the browser client from the proprietary WL-Proxy-Client-IP header, instead of the Web server.\n\n- **No**—Selecting No for the server or cluster disables the weblogic-plugin-enabled parameter (weblogic-plugin-enabled=false) in the config.xml file.\n\n- **Default**—When Default is selected for WebLogic Plug-In Enabled in the servers page, then the servers will inherit the value selected for WebLogic Plug-In Enabled for the cluster. When Default is selected for WebLogic Plug-In Enabled in the clusters page, then the clusters will inherit the value selected for WebLogic Plug-In Enabled for the domain.\n\n### 2.3 Configuring the Oracle WebLogic Server Proxy Plug-In Using Fusion Middleware Control\n\nUse Fusion Middleware Control to configure the module. To configure the module, complete the following tasks:\n\n- **Task 1: Navigate to the mod_wl_ohs Configuration Page**\n- **Task 2: Specify the Configuration Settings**\n- **Task 3: Configure Expression Overrides or Location Overrides (Optional)**\n- **Task 4: Apply Your Changes**\n\n#### 2.3.1 Task 1: Navigate to the mod_wl_ohs Configuration Page\n\nThe mod_wl_ohs configuration page contains the parameters for configuring the Oracle WebLogic Server Proxy Plug-In.\n\n1. Ensure that you have fulfilled the prerequisites listed in Preparing for Configuring the Oracle WebLogic Server Proxy Plug-In.\n\n2. Select Administration from the Oracle HTTP Server menu.\n\n3. Select Configuration from the Administration menu. The Configuration page appears.\nThe following table describes the fields in the mod_wl_ohs page.\n<table>\n<thead>\n<tr>\n<th>Field</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Provide WebLogic Cluster</td>\n<td>List of Oracle WebLogic clusters that can be used for load balancing. The server or cluster list is a list of <code>host:port</code> entries. If a mixed set</td>\n</tr>\n<tr>\n<td>Details</td>\n<td>of clusters and single servers is specified, the dynamic list returned for this parameter will return only the clustered servers.</td>\n</tr>\n<tr>\n<td></td>\n<td>If you are not sure of the correct cluster, you can click the search icon to see a list of all associated clusters. For more information, see</td>\n</tr>\n<tr>\n<td></td>\n<td>Using the Search Function.</td>\n</tr>\n<tr>\n<td></td>\n<td>The module does a simple round-robin between all available servers. The server list specified in this property is a starting point for the</td>\n</tr>\n<tr>\n<td></td>\n<td>dynamic server list that the server and module maintain. Oracle WebLogic Server and the module work together to update the server list</td>\n</tr>\n<tr>\n<td></td>\n<td>automatically with new, failed, and recovered cluster members.</td>\n</tr>\n<tr>\n<td></td>\n<td>You can disable the use of the dynamic cluster list by disabling the Dynamic Server List ON field. The module directs HTTP requests containing</td>\n</tr>\n<tr>\n<td></td>\n<td>a cookie, URL-encoded session, or a session stored in the POST data to the server in the cluster that originally created the cookie.</td>\n</tr>\n<tr>\n<td>Provide WebLogic Server</td>\n<td>• WebLogic Host</td>\n</tr>\n<tr>\n<td>Host and Port Details</td>\n<td>Oracle WebLogic Server host (or virtual host name as defined in Oracle WebLogic Server) to which HTTP requests should be forwarded. If you are</td>\n</tr>\n<tr>\n<td></td>\n<td>using a WebLogic cluster, use the WebLogic Cluster parameter instead of WebLogic Host.</td>\n</tr>\n<tr>\n<td></td>\n<td>If you are not sure of the correct server, you can click the search icon to see a list of all associated clusters. For more information, see</td>\n</tr>\n<tr>\n<td></td>\n<td>Using the Search Function.</td>\n</tr>\n<tr>\n<td></td>\n<td>• WebLogic Port</td>\n</tr>\n<tr>\n<td></td>\n<td>Port at which the Oracle WebLogic Server host is listening for connection requests from the module (or from other servers). (If you are using</td>\n</tr>\n<tr>\n<td></td>\n<td>SSL between the module and Oracle WebLogic Server, set this parameter to the SSL listen port.)</td>\n</tr>\n<tr>\n<td>Dynamic Server List ON</td>\n<td>When set to OFF, the module ignores the dynamic cluster list used for load balancing requests proxied from the module and only uses the static</td>\n</tr>\n<tr>\n<td>OFF</td>\n<td>list specified with the WebLogic Cluster parameter. Normally this parameter should be set to ON.</td>\n</tr>\n<tr>\n<td></td>\n<td>There are some implications for setting this parameter to OFF:</td>\n</tr>\n<tr>\n<td></td>\n<td>• If one or more servers in the static list fails, the module could waste time trying to connect to a terminated server, resulting in decreased</td>\n</tr>\n<tr>\n<td></td>\n<td>performance.</td>\n</tr>\n<tr>\n<td></td>\n<td>• If you add a new server to the cluster, the module cannot proxy requests to the new server unless you redefine this parameter. Oracle</td>\n</tr>\n<tr>\n<td></td>\n<td>WebLogic Server automatically adds new servers to the dynamic server list when they become part of the cluster.</td>\n</tr>\n</tbody>\n</table>\n### Task 2: Specify the Configuration Settings\n\nSpecify the configuration settings for the Oracle WebLogic Server Proxy Plug-In. In the General section, you can configure mod_wl_ohs for a WebLogic cluster or for WebLogic servers.\n\n- If you select the **Provide WebLogic Cluster Details** radio button, then provide values for the WebLogic Cluster, Dynamic Server List ON, Error Page, WebLogic Temp Directory, and Exclude Path or MIME Type fields.\n\n- If you select the **Provide WebLogic Server Host and Port Details** radio button, then provide values for the WebLogic Host, WebLogic Port, Dynamic Server List...\nON, Error Page, WebLogic Temp Directory, and Exclude Path or MIME Type fields.\n\n2.3.3 Task 3: Configure Expression Overrides or Location Overrides (Optional)\n\nIf necessary, you can add expression or location overrides to your configuration.\n\n1. Add any expression overrides in the Match Expression field.\n2. Add any location overrides in the Location table.\n a. Click Add Row to create a new row.\n b. Enter the base URI for which the associated directives become effective.\n c. Complete the WebLogic Cluster, WebLogic Host, and WebLogic Port fields. You can automatically complete these fields by clicking AutoFill (see Using the AutoFill Function).\n d. Complete the Path Trim field.\n\n According to the RFC specification, generic syntax for URL is:\n \n \\[[PROTOCOL]://[HOSTNAME]:{PORT}/{PATH}/{FILENAME};{PATH_PARAMS}/\n \\{QUERY_STRING}\\... \n\n Path Trim specifies the string trimmed by the module from the {PATH}/\n {FILENAME} portion of the original URL, before the request is forwarded to WebLogic Server. For example, if the URL:\n\n http://myWeb.server.com/weblogic/foo\n\n is passed to the module for parsing and if Path Trim has been set to strip off /weblogic before handing the URL to WebLogic Server, the URL forwarded to WebLogic Server is:\n\n http://myWeb.server.com:7002/foo\n\n **Note:**\n\n If you are converting an existing third-party server to proxy requests to WebLogic Server using the module for the first time, you must change application paths to /foo to include weblogic/foo. You can use Path Trim and Path Prepend in combination to change this path\n\n e. Complete the Path Prepend field.\n\n According to the RFC specification, generic syntax for URL is:\n \n \\[[PROTOCOL]://[HOSTNAME]:{PORT}/{PATH}/{FILENAME};{PATH_PARAMS}/\n \\{QUERY_STRING}\\... \n\n Path Prepend specifies the path that the module prepends to the {PATH} portion of the original URL, after Path Trim is trimmed and before the request is forwarded to WebLogic Server.\nNote:\nIf you need to append File Name, use the DefaultFileName module parameter instead of Path Prepend.\n\nf. Click Add Row again to save the new row\n\n2.3.4 Task 4: Apply Your Changes\n\nApply your changes to the mod_wl_ohs Configuration Page and restart Oracle HTTP Server.\n\n1. If the settings are correct, click Apply to apply the changes. If the settings are incorrect or you decide to not apply the changes, click Revert to return to the original settings.\n\n2. Restart Oracle HTTP Server by selecting Control from the Oracle HTTP Server menu, and then selecting Start Up.\n\nThe module configuration is saved and displayed on the Configuration page.\n\n2.3.5 Using the Search Function\n\nThe search function allows you to search for a particular WebLogic Cluster or WebLogic Host that is available to the selected Oracle HTTP Server instance. By clicking the search icon, you can see a list of clusters or servers available to the selected Oracle HTTP Server instance. To use the search function, do the following:\n\n1. Click the search icon for either WebLogic Cluster or WebLogic Host. The Select WebLogic Cluster/Server dialog box appears.\n\n2. Select the cluster or server you want to use and click OK.\n\nThe selected cluster or server name appears in the appropriate field.\n\n2.3.6 Using the AutoFill Function\n\nNote:\nThe AutoFill function is available only if you are using Oracle WebLogic Server in full-JRF mode. It is not available if you are using Restricted-JRF.\n\nYou can easily add valid WebLogic Server and endpoint locations for a specified Base URL to the Locations table on the Oracle WebLogic Server Proxy Plug-In Configuration screen by using the AutoFill button. To do so:\n\n1. Click Add to add a new location,\n\n2. Enter a location name in the Location field.\n\n3. Click AutoFill.\n\nData for any location of the same name will be updated and any new locations will be added to the table.\n2.4 Configuring the Oracle WebLogic Server Proxy Plug-In Manually\n\nYou can configure the Oracle WebLogic Server Proxy Plug-In manually by specifying directives in the mod_wl_ohs.conf file.\n\n1. Ensure that you have fulfilled the prerequisites listed in Preparing for Configuring the Oracle WebLogic Server Proxy Plug-In.\n\n2. Open the mod_wl_ohs.conf file in a text editor. This file is located in the following directory:\n\n\\[ \\text{DOMAIN}\\_\\text{HOME}/config/fmwconfig/components/OHS/instances/instanceName \\]\n\n3. Add directives within the \\(<\\text{IfModule weblogic_module}>\\) element in the configuration file. For examples, see Examples of \\(<\\text{IfModule weblogic_module}>\\) Element Configurations.\n\nFor information about the other directives that you can specify in the mod_wl_ohs.conf file, see Parameters for Web Server Plug-Ins.\n\n4. Restart Oracle HTTP Server by using one of the techniques described in \"Starting Oracle HTTP Server\", in Administering Oracle HTTP Server.\n\n2.4.1 Examples of \\(<\\text{IfModule weblogic_module}>\\) Element Configurations\n\nThe configuration of the predefined \\(<\\text{IfModule weblogic_module}>\\) element determines how requests are sent to Oracle WebLogic Server. These examples demonstrate the different ways in which you can configure this element.\n\n---\n\n**Note:**\n\nOracle recommends that you specify directives within the predefined \\(<\\text{IfModule weblogic_module}>\\) element.\n\nIf you specify directives outside the predefined \\(<\\text{IfModule weblogic_module}>\\) element, or in additional \\(<\\text{IfModule weblogic_module}>\\) elements, or in configuration files other than mod_wl_ohs.conf, the Oracle WebLogic Server Proxy Plug-In might work, but the configuration state of the module, as displayed in Fusion Middleware Control, could be inconsistent with the directives specified in the mod_wl_ohs.conf configuration file.\n\n---\n\nTo Forward Requests to a Single Oracle WebLogic Server Instance\n\nTo forward requests to an application running on a single Oracle WebLogic Server instance, specify the details of that destination server within a \\(<\\text{location}>\\) element.\n\n**Syntax:**\n\n\\(<\\text{IfModule weblogic_module}>\\)\n\n\\(<\\text{Location path}>\\)\n\nWLSRequest On\n\nWebLogicHost \\(\\text{host}\\)\n\nWeblogicPort \\(\\text{port}\\)\n\n\\(</\\text{Location}>\\)\n\n\\(</\\text{IfModule}>\\)\nExample:\nWith the following configuration, requests for the /myapp1 URI received at the Oracle HTTP Server listen port will be forwarded to /myapp1 on the Oracle WebLogic Server with the listen port localhost:7001.\n\n```\n<IfModule weblogic_module>\n <Location /myapp1>\n WLSRequest On\n WebLogicHost localhost\n WeblogicPort 7001\n </Location>\n</IfModule>\n```\n\nTo Forward Requests to a Cluster of Oracle WebLogic Server Instances\n\nTo forward requests to an application running on a cluster of Oracle WebLogic Server instances, specify the details of that destination cluster within a new `<location>` element.\n\nSyntax:\n\n```\n<IfModule weblogic_module>\n <Location path>\n WLSRequest On\n WebLogicCluster host:port,host:port,...\n </Location>\n</IfModule>\n```\n\nExample:\nWith the following configuration, requests for the /myapp2 URI received at the Oracle HTTP Server listen port will be forwarded to /myapp2 the Oracle WebLogic Server cluster containing the managed servers with the listen ports localhost:8002 and localhost:8003.\n\n```\n<IfModule weblogic_module>\n <Location /myapp2>\n WLSRequest On\n WebLogicCluster localhost:8002,localhost:8003\n </Location>\n</IfModule>\n```\n\nTo Configure Multiple Destinations\n\nTo configure multiple destinations—say, an application running on a single Oracle WebLogic Server instance and another application running on a cluster—you must specify each destination in a distinct `<location>` child element. All the `<location>` child elements should be at the same level within the `<ifModule weblogic_module>` element, as shown in the following syntax:\n\n```\n<IfModule weblogic_module>\n #For an application running on a single server instance\n <Location path1>\n WLSRequest On\n WebLogicHost host\n WeblogicPort port\n </Location>\n #For an application running on a cluster\n <Location path2>\n WLSRequest On\n WebLogicCluster host:port,host:port,...\n </Location>\n</IfModule>\n```\nTo Link to Managed Servers\n\nTo configure the Oracle WebLogic Server Proxy Plug-In so that it can link to managed servers, for example to enable a high availability deployment of Oracle HTTP Server, edit the mod_wl_ohs.conf file as follows:\n\n```apache\n<IfModule mod_weblogic.c>\n WebLogicCluster apphost1.mycompany.com:7050,apphost2.mycompany.com:7050\n MatchExpression *.jsp\n</IfModule>\n\n<Location /weblogic>\n WLSRequest On\n WebLogicCluster apphost1.mycompany.com:7050,apphost2.com:7050\n DefaultFileName index.jsp\n</Location>\n```\n\n**Note:**\n\nIf you are using SSL termination and routing requests to WebLogic, the following additional configuration is required.\n\nIn the WebLogic console, **WebLogic Plugin Enabled** must be set to true, either at the domain, cluster or Managed Server level.\n\nIn the Location block which directs requests to the WebLogic managed servers, one of the following lines also must be added.\n\n```\nWLProxySSL ON\nWLProxySSLPassThrough ON\n```\n\n(to help determine which parameter to use, see [SSL Parameters for Web Server Plug-Ins](#))\n\nFor example:\n\n```apache\n<Location /weblogic>\n WLSRequest On\n WebLogicCluster apphost1.mycompany.com:7050,apphost2.com:7050\n WLProxySSL On\n WLProxySSLPassThrough ON\n DefaultFileName index.jsp\n</Location>\n```\n\nAfter enabling the WebLogic plugin, restart the Administration Server.\n\nFor more information, see \"Terminating SSL Requests\" in *Administering Oracle HTTP Server*.\n\nThese examples show two different ways of routing requests to Oracle WebLogic managed servers:\n\n- The `<IfModule>` block sends any requests ending in *.jsp to the WebLogic Managed Server cluster located on Apphost1 and Apphost2.\nThe \\textit{<Location>} block sends any requests with URLs prefixed by /weblogic to the WebLogic Managed Server cluster located on Apphost1 and Apphost2.\n\nTo Configure One-way and Two-way SSL\n\nFor information about configuring the Oracle WebLogic Server Proxy Plug-In to support one-way and two-way SSL between Oracle HTTP Server and Oracle WebLogic Server, see Using SSL with Plug-Ins.\n\n### 2.5 Understanding Oracle WebLogic Server Proxy Plug-In Performance Metrics\n\nOracle HTTP Server provides performance metrics specific to the Oracle WebLogic Server Proxy Plug-In (mod_wl_ohs) module, where a request is proxied to the backend WebLogic server.\n\nThese metrics are provided through the Oracle Dynamic Monitoring Service (DMS) which enables Oracle Fusion Middleware components to provide administration tools, such as Fusion Middleware Control, with data regarding the component's performance, state and on-going behavior. For the Oracle WebLogic Server Proxy Plug-In module, for example, it could return the number of requests proxied, the number of failed requests, and other specific metrics. For more information on DMS, see \"Using the Oracle Dynamic Monitoring Service\" in Tuning Performance Guide.\n\n**Note:**\n\nThe Oracle WebLogic Server Proxy Plug-In module metrics are available only for Oracle HTTP Server and Apache server plug-ins. They are not available for Microsoft IIS and iPlanet server plug-ins.\n\nThis section contains the following information on DMS metrics.\n\n- Configuring DMS Metrics for Oracle HTTP Server Proxy Plug-in—How to configure DMS metrics for Oracle WebLogic Server.\n- Viewing Performance Metrics for Oracle HTTP Server Proxy Plug-in—How to view DMS metrics for Oracle WebLogic Server.\n- DMS State Metrics—These metrics represent a single data point, for example, a counter, a status and so on.\n- DMS Event Metrics—These metrics represent an event, for example a login failure and so on.\n- DMS PhaseEvent Metrics—These metrics represent a \"phase\" of an event.\n\n### 2.5.1 Configuring DMS Metrics for Oracle HTTP Server Proxy Plug-in\n\nThe DMS metrics for Oracle WebLogic Server Proxy Plug-In are enabled by default in the \\texttt{admin.conf} file. They are included as part of the regular DMS metrics collection.\n\n### 2.5.2 Viewing Performance Metrics for Oracle HTTP Server Proxy Plug-in\n\nYou can view the performance metrics by using either the administration port, WLST commands or Fusion Middleware Control. For details of each of the performance metrics, see DMS State Metrics, DMS Event Metrics, and DMS PhaseEvent Metrics.\nUsing the Administration Port:\n\nIf administration port is configured, for example, at 127.0.0.1:9999, then you can view the raw DMS metrics at the URL http://127.0.0.1/dms/.\n\nThe metrics under the section /WebLogicProxy [type=OHSWebLogic] are the metrics coming from Oracle WebLogic Server plug-in.\n\nUsing WLST (Collocated Mode Only)\n\nUse the WLST command `displayMetricTables` to view performance metrics, for example:\n\n```java\ndisplayMetricTables(servertype=\"OHS\", servers=<instancename>)\n```\n\nThe metrics under the section /WebLogicProxy [type=OHSWebLogic] are the metrics coming from Oracle WebLogic Server Proxy Plug-in.\n\nUsing Fusion Middleware Control (Collocated Mode Only)\n\nTo view performance metrics in Fusion Middleware Control, select Oracle HTTP Server, then Monitoring, then Performance Summary. The metrics towards the bottom of this page will have Oracle WebLogic Server Proxy Plug-in specific metrics. See \"Viewing Performance Metrics\" in Administering Oracle HTTP Server.\n\n2.5.3 DMS State Metrics\n\nA state metric tracks system status information or to track a metric that is not associated with an event. Table 2-1 describes the State metrics available for the Oracle WebLogic Server Proxy Plug-In module.\n\nThese metrics can be returned for Oracle WebLogic Server and Apache HTTP Server Plug-ins.\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>totalDeclines</td>\n<td>The total number of requests declined (not processed by <code>mod_wl_ohs</code>). This number indicates the requests that are not configured, and/or rejected by the plug-in (for example, custom HTTP methods are always rejected by the plug-in)</td>\n</tr>\n<tr>\n<td>totalErrors</td>\n<td>Number of requests that could not be processed successfully. See Event Metrics for errors.</td>\n</tr>\n<tr>\n<td>totalHandled</td>\n<td>The total number of requests serviced by the <code>mod_wl_ohs</code> plug-in.</td>\n</tr>\n<tr>\n<td>totalRequests</td>\n<td>The total number of requests received by <code>mod_wl_ohs</code>. The number includes all the requests that are targeted to the plug-in, plus the requests that are not targeted to any module (not configured).</td>\n</tr>\n<tr>\n<td>totalRetries</td>\n<td>Number of times a request was retried. Requests are generally retried on failure (depending on configuration). If a request is ever retried, this metric will increment (once per request, irrespective of how many times the request was retried).</td>\n</tr>\n</tbody>\n</table>\n### Table 2-1 (Cont.) State Metrics for the Oracle WebLogic Server Proxy Plug-In Module\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>totalSuccess</td>\n<td>The number of requests successfully processed. If the requests are processed successfully (proxied to Oracle WebLogic Server, and sent the response back to client), then this metric will be incremented.</td>\n</tr>\n<tr>\n<td>websocketActive</td>\n<td>Number of WebSocket upgrade requests currently active.</td>\n</tr>\n<tr>\n<td>websocketClose</td>\n<td>Number of WebSocket upgrade requests closed. If the WebSocket session is terminated (for any reason), then this metric is updated.</td>\n</tr>\n<tr>\n<td>websocketMax</td>\n<td>Maximum number of simultaneous WebSocket requests that can be active. If the WLMaxWebSocketClients parameter is configured, the value will be the lower of these:</td>\n</tr>\n<tr>\n<td></td>\n<td>• The configured value, OR</td>\n</tr>\n<tr>\n<td></td>\n<td>• 0.75 of the value of MaxRequestWorkers (Oracle HTTP Server and Apache 2.4), OR</td>\n</tr>\n<tr>\n<td></td>\n<td>• 0.75 of the value of MaxClients (Apache 2.2), OR</td>\n</tr>\n<tr>\n<td></td>\n<td>• 0.75 of the value of ThreadsPerChild (Oracle HTTP Server and Apache 2.2/2.4, Windows only)</td>\n</tr>\n<tr>\n<td></td>\n<td>If WLMaxWebSocketClients parameter is not configured, the value will be:</td>\n</tr>\n<tr>\n<td></td>\n<td>• 0.5 of the value of MaxRequestWorkers (Oracle HTTP Server and Apache 2.4), OR</td>\n</tr>\n<tr>\n<td></td>\n<td>• 0.5 of the value of MaxClients (Apache 2.2), OR</td>\n</tr>\n<tr>\n<td></td>\n<td>• 0.5 of the value of ThreadsPerChild (Oracle HTTP Server and Apache 2.2/2.4, Windows only)</td>\n</tr>\n<tr>\n<td></td>\n<td>For more information on the WLMaxWebSocketClients parameter, see Tuning Oracle HTTP Server and Apache HTTP Server for High Throughput for WebSocket Upgrade Requests.</td>\n</tr>\n<tr>\n<td>websocketPercent</td>\n<td>This value is defined by the number of active WebSockets (websocketActive) divided by the maximum number of simultaneous WebSocket requests (websocketMax) multiplied by 100: (websocketActive/websocketMax)*100.</td>\n</tr>\n<tr>\n<td>websocketRequests</td>\n<td>The number of WebSocket upgrade requests made. If the request URI is an WebSocket upgrade request, this metric will be incremented.</td>\n</tr>\n<tr>\n<td>websocketSuccess</td>\n<td>Number of WebSocket upgrade requests completed successfully. If Oracle WebLogic Server responds to a WebSocket upgrade request with 101 Switching Protocols, then this metric is updated.</td>\n</tr>\n</tbody>\n</table>\n\n### 2.5.4 DMS Event Metrics\n\nA DMS event metric counts system events. A DMS event tracks system events that have a short duration, or where the duration of the event is not of interest but the\noccurrence of the event is of interest. Table 2-2 describes the Event metrics available for the Oracle WebLogic Server Proxy Plug-In module.\n\nThese metrics can be returned for Oracle WebLogic Server and Apache HTTP Server Proxy Plug-ins.\n\n**Table 2-2 Event Metrics for the Oracle WebLogic Server Proxy Plug-In Module.**\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>errConnRefused</td>\n<td>The number of CONNECTION_REFUSED errors. Indicates the number of times the configured WebLogicHost and/or WebLogicPort is either not reachable or not listening.</td>\n</tr>\n<tr>\n<td>errNoResources</td>\n<td>The number of NO_RESOURCES errors. One scenario where this exception can occur is when SSL is configured in the plug-in, but the corresponding SSL configuration is not defined in the managed server.</td>\n</tr>\n<tr>\n<td>errOthers</td>\n<td>The number of any other errors. For example, POST data size is greater than the value of MaxPostSize.</td>\n</tr>\n<tr>\n<td>errReadClient</td>\n<td>The number of READ_ERROR_FROM_CLIENT errors. Indicates the number of times that the plug-in could not read from the client (browser).</td>\n</tr>\n<tr>\n<td>errReadServer</td>\n<td>The number of READ_ERROR_FROM_SERVER errors. Indicates the number of times a read operation could not be successfully performed on Oracle WebLogic Server.</td>\n</tr>\n<tr>\n<td>errReadTimeout</td>\n<td>The number of READ_TIMEOUT errors. An example is Oracle WebLogic Server not responding within WLIOTimeoutSecs.</td>\n</tr>\n<tr>\n<td>errWriteClient</td>\n<td>The number of WRITE_ERROR_TO_CLIENT errors. Indicates the number of times that the plug-in could not write to client. This can be seen when the client sends a request but closes the connection before receiving the response.</td>\n</tr>\n<tr>\n<td>errWriteWLS</td>\n<td>The number of WRITE_ERROR_TO_SERVER errors. Indicates the number of times that the plug-in could not write to Oracle WebLogic Server.</td>\n</tr>\n<tr>\n<td>wsClientClose</td>\n<td>Number of WebSocket upgrade requests closed by client. If the client sends a WebSocket upgrade request, and client closes the connection, then this metric is updated.</td>\n</tr>\n<tr>\n<td>wsErrorClose</td>\n<td>Number of WebSocket sessions terminated due to error. If there is any error which causes the WebSocket connection to close, then this metric is updated.</td>\n</tr>\n<tr>\n<td>wsNoUpgrade</td>\n<td>The number of times the WebSocket upgrade request was rejected. The response to WebSocket upgrade request is not "101 Switching Protocols". This can happen when the upgrade request is sent to Oracle WebLogic Server that does not support WebSockets (Oracle WebLogic Server version 12.1.2 or earlier).</td>\n</tr>\n</tbody>\n</table>\n### 2.5.5 DMS PhaseEvent Metrics\n\nA DMS PhaseEvent metric measures the time spent in a specific section of code that has a beginning and an end. A PhaseEvent tracks time in a method or in a block of code. For each phase event, an “active count”, “completed count”, “total time”, “min time”, “max time” and “average time” value is included. Table 2-3 describes the PhaseEvent metrics available for the Oracle WebLogic Server Proxy Plug-In module.\n\nThese metrics can be returned for Oracle WebLogic Server and Apache HTTP Server Proxy Plug-ins.\n\n#### Table 2-3 PhaseEvent Metrics for the Oracle WebLogic Server Proxy Plug-In Module\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>websocketPhase</td>\n<td>WebSocket communication in progress. The phase (time) between "WebSocket upgrade succeeded" and "WebSocket connection closed"</td>\n</tr>\n<tr>\n<td>wlsWait</td>\n<td>The phase (time) between "the request sent to Oracle WebLogic Server" and "Waiting for response".</td>\n</tr>\n</tbody>\n</table>\n\n### 2.6 Deprecated Directives for Oracle HTTP Server\n\nThe WebLogic Server plug-in logs for Oracle WebLogic Server Proxy Plug-In are now part of the Web Server error log mechanism. References can be identified with module name as `weblogic`, for example:\n\n```\n[2015-05-14T00:43:27.8355-06:00] [OHS] [TRACE:16] [OH99999] [weblogic] [client_id: :: 1] [host_id: XXXXXXXX] [host_addr: XX.XXX.XXX.XXX] [pid: 1240] [tid: 2424] [user: sramavan] [ecid: 00IT9hK40rhFWo0zbnn063z0BvEE3zsYykm0000J0000000H] [rid: 0] [VirtualHost: main] ================New Request: [GET /favicon.ico HTTP/1.1] =================\n```\n\nThe WLLogFile and Debug directives are deprecated. If the configuration uses these directives, the following note will appear in the node manager plug-in log file (ohs_nm.log):\n\n```\n<2015-05-14 00:36:25> <INFO> <OHS-0> <[Thu May 14 00:36:25.723286 2015] [weblogic:warn] [pid 5084:tid 668] The Debug directive is ignored. The web server log level is used instead.>\n```\n\n```\n<2015-05-14 00:36:25> <INFO> <OHS-0> <[Thu May 14 00:36:25.724263 2015] [weblogic:warn] [pid 5084:tid 668] The WLLogFile directive is ignored. The web server log file is used instead.>\n```\nTo enable plug-in logs:\n\n- If OraLogMode is set to ODL-text, set OraLogSeverity to TRACE:16. The logs appear in the directory OraLogDir (instance-name.log). This is the default.\n\n- If OraLogMode is set to apache, set LogLevel to debug. The directive ErrorLog points to the file where the errors are logged.\n\nFor more details on Managing Oracle HTTP Server Logs, See \"Managing Oracle HTTP Server Logs\" in Administering Oracle HTTP Server.\n\n2.7 Troubleshooting Oracle WebLogic Server Proxy Plug-In Implementations\n\nYou might encounter some of the following problems when using the Oracle WebLogic Server Proxy Plug-In. Descriptions of how to solve these problems are provided.\n\n- WLS Session Issues\n- CONNECTION_REFUSED Errors\n- NO_RESOURCES Errors\n- Changing the Oracle WebLogic Server Keystore Causes Unexpected Behavior\n\n2.7.1 WLS Session Issues\n\nThe Oracle WebLogic Server Proxy Plug-In routes the requests to backend Oracle WebLogic Server or cluster. Oracle WebLogic Server maintains sessions so that subsequent requests from the same client are routed to the same server. However, due to various reasons, if the Oracle WebLogic Server Proxy Plug-In cannot communicate with the Oracle WebLogic Server server, the request is handled in the following ways:\n\n- If the request is routed to a single WebLogic Server instance, the Oracle WebLogic Server Proxy Plug-In continues trying to connect to that same WebLogic Server instance for the maximum number of retries as specified by the ratio of ConnectTimeoutSecs and ConnectRetrySecs. If all attempts fail, an HTTP 503 error message is returned back to the client.\n\n- If the request is routed to WebLogic Cluster, then the current WLS server is marked as bad, and the request is routed to the next available WLS server. If all attempts fail, an HTTP 503 error message is returned back to the client.\n\nIn addition to sending a HTTP 503 error message, the following is displayed as a response in the HTTP client:\n\nFailure of Web Server bridge: \nNo backend server available for connection: timed out after xx seconds or idempotent set to OFF or method not idempotent.\n\n2.7.2 CONNECTION_REFUSED Errors\n\nOccasionally, under stress conditions, a few requests might fail with the following error logged in the error log file.\n\nweblogic: Trying GET /uri at backend host 'xx.xx.xx.xx/port; got exception \n'CONNECTION_REFUSED [os error=xxx, line xxxx of URL.cpp]: apr_socket_connect call failed with error=xxx, host=xx.xx.xx.xx, port=xxxx'\nAs mentioned in Tips for Reducing CONNECTION_REFUSED Errors, Oracle WebLogic Server might have reached the maximum allowed backlog connections. To resolve, follow the steps mentioned in Tips for Reducing CONNECTION_REFUSED Errors.\n\n2.7.3 NO_RESOURCES Errors\n\nOccasionally, under stress conditions, a few requests might fail with the following error logged in the error log file.\n\nweblogic: *******Exception type [NO_RESOURCES] (apr_socket_connect call failed with error=70007, host=xx.xx.xx.xx, port=xxxx) raised at line xxxx of URL.cpp\n\nThis usually occurs if Oracle WebLogic Server is too busy to respond to the connect request from the Oracle WebLogic Server Proxy Plug-In. This can be resolved by setting WLSocketTimeoutSecs to a higher value. This allows the Oracle WebLogic Server Proxy Plug-In to wait longer for the connect request to be responded to by the Oracle WebLogic Server.\n\n2.7.4 Changing the Oracle WebLogic Server Keystore Causes Unexpected Behavior\n\nIf the Oracle WebLogic Server keystore is changed (for example, by setting up backend one-way SSL between Oracle HTTP Server and Oracle WebLogic Server) it is possible to break communication between Oracle WebLogic Server and the NodeManager. If this happens, this will also affect all provisioning and process management commands issued through WLST. The error messaging in this situation is poor and the situation can be confusing. For example, some errors indicate NodeManager is down, when the user can see that it is clearly up.\n\nHere are a few examples of the unexpected behavior that can occur. Note that in these examples, the NodeManager is up and running.\n\n- All state() commands run against Oracle HTTP Server instances return UNKNOWN.\n\n wls:/OHSDomain/serverConfig/> state('ohs1')\n Current state of \"ohs1\" : UNKNOWN\n\n- Oracle HTTP Server process management commands return an SSLEngine failure:\n\n wls:/OHSDomain/serverConfig/> start('ohs1')\n Starting system component \"ohs1\" ...\n\n General SSLEngine problem\n Traceback (innermost last):\n File \"<console>\", line 1, in ?\n File \"<iostream>\", line 1384, in start\n File \"<iostream>\", line 553, in raiseWLSTException\n WLSTException: Error occurred while performing start : System component with name \"ohs1\" failed to start : General SSLEngine problem\n ....\n\n- The Oracle HTTP Server custom command ohs_createInstance returns a message that NodeManager is down and the command will be completed when it is back up, for example:\n\n ohs_createInstance(instanceName='ohs1',machine='myMachine.myCompany.com')\n ....\nThe node manager for \"ohns1\" is not reachable. Changes will be completed when the node manager is available.\nThe node manager error is: Node Manager is not available on machine\nmyMachine.myCompany.com\nActivation completed.\n\nWorkaround:\nTo workaround this issue, add the NodeManager demo trust certificate to the Java standard trust. Note that this workaround applies only when the user is setting up one-way backend SSL. Other steps may be needed for other scenarios.\n\n1. Use keytool command to export the NodeManager demo trust certificate to the Java keystore.\n\n keytool -exportcert -rfc -alias wlscertgenca -storepass\n DemoTrustKeyStorePassPhrase -file /<path to location of nmCert.crt> -\n keystore $ORACLE_HOME/wlserver/server/lib/DemoTrust.jks\n\n2. Use keytool command to import the NodeManager demo trust certificate to the Java standard trust.\n\n keytool -importcert -alias wlscertgenca -file /<path to location of\n nmCert.crt> -keystore $JAVA_HOME/jre/lib/security/cacerts -trustcacerts -\n storepass changeit -noprompt\n\n3. Oracle WebLogic Server may need to be bounced (shutdown and restarted) after applying the keytool commands.\nThis chapter describes how to install and configure the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server. It contains the following sections:\n\n- Apache HTTP Server Support Note\n- Install the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server\n- Configure the Apache HTTP Server Plug-In\n- Understanding DMS Metrics for Apache HTTP Server Plug-in\n- Deprecated Directives for Apache HTTP Server\n\nNote:\n\nFor proxying requests from Oracle HTTP Server to Oracle WebLogic Server, use the mod_wl_ohs plug-in, which is similar to the plug-in for Apache HTTP Server, but need not be downloaded and installed separately. For information about configuring mod_wl_ohs, see Configuring the Plug-In for Oracle HTTP Server.\n\n3.1 Apache HTTP Server Support Note\n\nThe Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server is supported on Apache 2.2 and 2.4 web servers and can front-end WebSocket applications.\n\n3.2 Install the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server\n\nAfter you download the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server, as described in Availability of Oracle WebLogic Server Proxy Plug-In, you can install it as an Apache HTTP Server module in your Apache HTTP Server installation.\n\n- Installation Prerequisites\n- Installing the Apache HTTP Server Plug-In\n\n3.2.1 Installation Prerequisites\n\nBefore you install the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server, complete these installation and verification tasks.\n• Download the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server, as described in Availability of Oracle WebLogic Server Proxy Plug-In.\n\n• Extract the plug-ins zip distribution to PLUGIN_HOME; for example, /home/myhome/weblogic-plugins-12.2.1/. This is the directory to which the extract the plug-in is extracted.\n\nThis distribution contains these files:\n\n<table>\n<thead>\n<tr>\n<th>(path)/filename</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>README.txt</td>\n<td>The README file for the plug-in.</td>\n</tr>\n<tr>\n<td>bin/orapki.bat</td>\n<td>orapki tool for configuring Oracle wallets</td>\n</tr>\n<tr>\n<td>jlib/*.jar</td>\n<td>orapki helper Java libraries</td>\n</tr>\n<tr>\n<td>lib/mod_wl.so</td>\n<td>WebLogic proxy module for Apache 2.2</td>\n</tr>\n<tr>\n<td>lib/*.so</td>\n<td>Helper libraries</td>\n</tr>\n<tr>\n<td>lib/mod_wl_24.so</td>\n<td>WebLogic proxy module for Apache 2.4</td>\n</tr>\n</tbody>\n</table>\n\n• Install JDK 8 to use SSL. The JDK 8 installation is required to use the orapki utility, which manages public key infrastructure (PKI) elements, such as wallets and certificate revocation lists, for use with SSL.\n\n• Ensure that you have a supported Apache HTTP Server installation.\n\nFor more information, see:\n\n\n• Ensure that a supported version of Oracle WebLogic Server is configured and running on a target system. This server does not need to be running on the system on which you extracted the plug-in zip distribution. For the supported Oracle WebLogic Server versions, see:\n\n\n### 3.2.2 Installing the Apache HTTP Server Plug-In\n\nThe Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server is distributed as a shared object (.so) file. You can obtain the plug-in here:\n\nhttp://www.oracle.com/technetwork/middleware/webtier/overview/index.html\n\nTo install the Apache HTTP Server plug-in:\n\n1. Ensure that the weblogic-plugins-12.2.1/lib folder is included in LD_LIBRARY_PATH on UNIX systems (and PATH on Windows systems). If you do not do this, then you see linkage errors when starting Apache HTTP Server.\n2. In the location where you unzipped the downloaded plug-in file, locate lib/mod_wl.so; for example, /home/myhome/weblogic-plugins-12.2.1/lib/mod_wl.so.\n\n3. Verify that the mod_so.c module is enabled.\n\nIf you installed Apache HTTP Server using the script supplied by Apache, mod_so.c is already enabled. Verify that mod_so.c is enabled by executing the following command:\n\n- UNIX/Linux\n\n $ APACHE_HOME/bin/apachectl -l\n\n (APACHE_HOME is the directory that contains the Apache HTTP Server installation.)\n\n This command lists all enabled modules. If mod_so.c is not listed, you must rebuild your Apache HTTP Server, making sure that the following configure option is specified:\n\n ...\n --enable-module=so\n ...\n\n4. Make a copy of the APACHE_HOME/bin/httpd.conf file for backup.\n\n5. Open the httpd.conf file.\n\n6. Depending on your version of Apache, use one of the following commands to install the plug-in:\n\n - Install the Apache HTTP Server plug-in module for Apache 2.2.x by adding the following line.\n ```bash\n LoadModule weblogic_module /home/myhome/weblogic-plugins-12.2.1/lib/mod_wl.so\n ```\n\n - Install the Apache HTTP Server plug-in module for Apache 2.4.x by adding the following line.\n ```bash\n LoadModule weblogic_module /home/myhome/weblogic-plugins-12.2.1/lib/mod_wl_24.so\n ```\n\n7. Verify the syntax of the httpd.conf file by running the following command:\n\n - UNIX/Linux\n\n $ > APACHE_HOME/bin/apachectl -t\n\n If the httpd.conf file contains any errors, the output of this command shows the errors; otherwise, the command returns the following:\n\n Syntax OK\n\n### 3.3 Configure the Apache HTTP Server Plug-In\n\nThis section describes how to edit the httpd.conf file to proxy requests by path or by MIME type, to enable HTTP tunneling, and to use other Oracle WebLogic Server plug-in parameters.\n\n- Configuring the httpd.conf File\n3.3.1 Configuring the httpd.conf File\n\nEdit the httpd.conf file in your Apache HTTP Server installation to configure the Apache HTTP Server plug-in. Complete these tasks:\n\n- Task 1: Configure MIME Requests\n- Task 2: Define Additional Parameters for Oracle WebLogic Server Proxy Plug-In\n- Task 3: Enable HTTP Tunneling (Optional)\n- Task 4: Verify and Apply Your Configuration\n\n3.3.1.1 Task 1: Configure MIME Requests\n\nYou can proxy requests by MIME type and/or by path. Open the httpd.conf file in a text editor.\n\n- Configuring Proxy Requests by MIME Type\n- Configuring Proxy Requests by Path\n\nNote:\n\nIf both MIME type and proxying by path are enabled, proxying by path takes precedence over proxying by MIME type.\n\n3.3.1.1.1 Configuring Proxy Requests by MIME Type\n\nFollow these steps to configure MIME requests by MIME type in the httpd.conf file.\n\n1. Add an `<IfModule>` block that defines one of the following:\n - For a non-clustered WebLogic Server: define the WebLogicHost and WebLogicPort parameters.\n - For a cluster of WebLogic Servers: define the WebLogicCluster parameter.\n\n Example:\n ```\n <IfModule mod_weblogic.c>\n WebLogicHost myweblogic.example.com\n WebLogicPort 7001\n DebugConfigInfo ON\n </IfModule>\n ```\n\n2. Add a MatchExpression line to the `<IfModule>` block.\n\n For example, the following `<IfModule>` block for a non-clustered WebLogic Server specifies that all files with MIME type .jsp are proxied:\n<IfModule mod_weblogic.c>\nWebLogicHost my-weblogic.server.com\nWebLogicPort 7001\nMatchExpression *.jsp\nDebugConfigInfo ON\n</IfModule>\n\nYou can also use multiple MatchExpressions, for example:\n\n<IfModule mod_weblogic.c>\nWebLogicHost my-weblogic.server.com\nWebLogicPort 7001\nMatchExpression *.jsp\nMatchExpression *.xyz\nDebugConfigInfo ON\n</IfModule>\n\nIf you are proxying requests by MIME type to a cluster of WebLogic Servers, use the WebLogicCluster parameter instead of the WebLogicHost and WebLogicPort parameters. For example:\n\n<IfModule mod_weblogic.c>\nWebLogicCluster wls1.com:7001,wls2.com:7001,wls3.com:7001\nMatchExpression *.jsp\nMatchExpression *.xyz\n</IfModule>\n\n### 3.3.1.1.1 Configuring Proxy Requests by Path\n\nFollow these steps to configure MIME requests by path in the httpd.conf file.\n\n1. Use the `<Location>` block and the WLSRequest statement to configure MIME requests by path. WLSRequest specifies the handler for the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server module. For example the following Location block proxies all requests containing /weblogic in the URL:\n\n ```\n <Location /weblogic>\n WLSRequest On\n PathTrim /weblogic\n </Location>\n ```\n\n2. Configure the PathTrim parameter inside the `<Location>` tag.\n\n The PathTrim parameter specifies a string trimmed from the beginning of the URL before the request is passed to the WebLogic Server instance (see General Parameters for Web Server Plug-Ins).\n\n These known issues arise when you configure the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server to use SSL:\n\n - The following configuration is incorrect:\n\n ```\n <Location /weblogic>\n WLSRequest On\n </Location>\n ```\n\n ```\n <IfModule mod_weblogic.c>\n WebLogicHost localhost\n WebLogicPort 7001\n PathTrim /weblogic\n </IfModule>\n ```\nThe following configuration is correct:\n\n```\n<Location /weblogic>\n WLSRequest On\n PathTrim /weblogic\n</Location>\n```\n\n- The current implementation of the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server does not support the use of multiple certificate files with Apache SSL.\n\n### 3.3.1.2 Task 2: Define Additional Parameters for Oracle WebLogic Server Proxy Plug-In\n\nDefine any additional parameters for the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server.\n\nThe Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server recognizes the parameters listed in General Parameters for Web Server Plug-Ins. To modify the behavior of your Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server, define these parameters either:\n\n- In a `<Location>` block, for parameters that apply to proxying by path, or\n- At global or virtual host scope, for parameters that apply to proxying by MIME type.\n\n### 3.3.1.3 Task 3: Enable HTTP Tunneling (Optional)\n\nYou can enable HTTP tunneling for the t3 or IIOP protocols by configuring `<Location>` blocks.\n\n- To enable HTTP tunneling if you are using the t3 protocol and weblogic.jar, add the following `<Location>` block to the httpd.conf file:\n\n ```\n <Location /bea_wls_internal>\n WLSRequest On\n </Location>\n ```\n\n- To enable HTTP tunneling if you are using the IIOP, the only protocol used by the WebLogic Server thin client, wlclient.jar, add the following `<Location>` block to the httpd.conf file:\n\n ```\n <Location /bea_wls_internal>\n WLSRequest On\n </Location>\n ```\n\n### 3.3.1.4 Task 4: Verify and Apply Your Configuration\n\nFollow these steps to verify your httpd.conf configuration and apply it to the Apache HTTP Server.\n\n1. Verify the syntax of the httpd.conf file by running the following command:\n\n - UNIX/Linux\n ```\n > APACHE_HOME/bin/apachectl -t\n ```\n \n If the httpd.conf file contains any errors, the output of this command shows the errors; otherwise, the command returns the following:\n\n `Syntax OK`\n2. Start the Apache HTTP Server.\n - UNIX/Linux\n \n > APACHE_HOME/bin/apachectl start\n\n\n### 3.3.2 Placing WebLogic Properties Inside Location or VirtualHost Blocks\n\nIf you choose to not use the `<IfModule>`, you can instead directly place the WebLogic properties inside `Location` or `<VirtualHost>` blocks. Consider the following examples of the `Location` and `<VirtualHost>` blocks:\n\n```\n<Location /weblogic>\n WLSRequest On\n WebLogicHost myweblogic.server.com\n WebLogicPort 7001\n</Location>\n\n<Location /weblogic>\n WLSRequest On\n WebLogicCluster w1s1.com:7001,w1s2.com:7001,w1s3.com:7001\n</Location>\n\n<VirtualHost apachehost:80>\n WLSRequest On\n WebLogicServer weblogic.server.com\n WebLogicPort 7001\n</VirtualHost>\n```\n\n### 3.3.3 Example: Configuring the Apache Plug-In\n\nThis example demonstrates basic instructions for quickly setting up the Apache plug-in to proxy requests to a backend WebLogic Server.\n\n1. Make a copy of `$APACHE_HOME/conf/httpd.conf` file.\n\n2. Edit the file to add the following code:\n\n ```\n ... \n LoadModule weblogic_module /home/myhome/weblogic-plugins-12.2.1/lib/mod_wl.so\n \n <IfModule mod_weblogic.c>\n WebLogicHost wls-host\n WebLogicPort wls-port\n </IfModule>\n \n <Location /mywebapp>\n WLSRequest On\n </Location>\n ...\n ```\n\n3. Include `$PLUGIN_HOME/lib` in the `LD_LIBRARY_PATH` by entering the following command:\n\n ```\n $ export LD_LIBRARY_PATH=/home/myhome/weblogic-plugin-12.2.1/lib:\n ```\nNote:\nYou can also update the `LD_LIBRARY_PATH` by copying the 'lib' contents to `APACHE_HOME/lib` or by editing the `APACHE_HOME/bin/apachectl` to update the `LD_LIBRARY_PATH`.\n\n4. At the prompt, start the Apache HTTP Server by entering:\n\n ```\n $ $(APACHE_HOME)/bin/apachectl start\n ```\n\n5. Send a request to `http://apache-host:apache-port/mywebapp/my.jsp` from the browser and validate the response\n\n### 3.3.4 Including a `weblogic.conf` File in the `httpd.conf` File\n\nTo keep several separate configuration files, you can define parameters in a separate configuration file called `weblogic.conf` file, by using the Apache HTTP Server `Include` directive in an `<IfModule>` block in the `httpd.conf` file.\n\n```\n<IfModule mod_weblogic.c>\n # Config file for WebLogic Server that defines the parameters\n Include conf/weblogic.conf\n</IfModule>\n```\n\nThe syntax of `weblogic.conf` files is the same as that for the `httpd.conf` file.\n\nThe following sections describe how to create `weblogic.conf` files, and include sample `weblogic.conf` files.\n\n- **Rules for Creating `weblogic.conf` Files**\n- **Sample `weblogic.conf` Configuration Files**\n- **Template for the Apache HTTP Server `httpd.conf` File**\n\n#### 3.3.4.1 Rules for Creating `weblogic.conf` Files\n\nBe aware of the following rules and best practices for constructing a `weblogic.conf` file.\n\n- Enter each parameter on a new line. Do not put \"=\" between a parameter and its value. For example:\n ```\n PARAM_1 value1\n PARAM_2 value2\n PARAM_3 value3\n ```\n\n- If a request matches both a MIME type specified in a `MatchExpression` in an `<IfModule>` block and a path specified in a `Location` block, the behavior specified by the `Location` block takes precedence.\n\n- If you use an Apache HTTP Server `<VirtualHost>` block, you must include all configuration parameters (`MatchExpression`, for example) for the virtual host within the `<VirtualHost>` block (see Apache Virtual Host documentation at `http://httpd.apache.org/docs/vhosts/`).\n\n- Sample `httpd.conf` file:\n\n ```\n <IfModule mod_weblogic.c>\n WebLogicCluster johndoe02:8005,johndoe:8006\n ```\nWLTempDir \"c:\\myTemp\"\nDebugConfigInfo ON\nKeepAliveEnabled ON\nKeepAliveSecs 15\n</IfModule>\n\n<Location /jurl>\nWLSRequest On\nWebLogicCluster myCluster:7001\nWLTempDir \"c:\\jurl\"\n</Location>\n\n<Location /web>\nWLSRequest On\nPathTrim /web\nWebLogicHost myhost\nWebLogicPort 8001\nWLTempDir \"c:\\web\"\n</Location>\n\n<Location /foo>\nWLSRequest On\nWebLogicHost myhost02\nWebLogicPort 8090\nWLTempDir \"c:\\foo\"\nPathTrim /foo\n</Location>\n\n- All the requests that match /jurl/* will have the POST data files in c:\\jurl and will reverse proxy the request to agarwalp01 and port 7001. All the requests that match /web/* will have the POST data files in c:\\web and will reverse proxy the request to myhost and port 8001. All the requests that match /foo/* will have the POST data files written to c:\\foo and will reverse proxy the request to myhost02 and port 8090.\n\n- You should use the MatchExpression statement instead of the <Files> block.\n\n### 3.3.4.2 Sample weblogic.conf Configuration Files\n\nThese examples of weblogic.conf files may be used as templates that you can modify to suit your environment and server. Lines beginning with # are comments.\n\n#### Example Using WebLogic Clusters\n\n```\n# These parameters are common for all URLs which are\ndirected to the current module. If you want to override\n# these parameters for each URL, you can set them again in\n# the <Location> or <Files> blocks. (Except WebLogicHost,\n# WebLogicPort, WebLogicCluster, and CookieName.)\n\n<IfModule mod_weblogic.c>\n WebLogicCluster w1s1.com:7001,w1s2.com:7001, w1s3.com:7001\n ErrorPage http://myerrorpage.mydomain.com\n MatchExpression *.jsp\n</IfModule>\n```\n\nIn the example, the MatchExpression parameter syntax for expressing the filename pattern, the WebLogic Server host to which HTTP requests should be forwarded, and various other parameters is as follows:\n\n```\nMatchExpression [filename pattern] [WebLogicHost=host] [paramName=value]\n```\nThe first MatchExpression parameter below specifies the filename pattern *.jsp, and then names the single WebLogicHost. The paramName=value combinations following the pipe symbol specify the port at which WebLogic Server is listening for connection requests, and also activate the Debug option. The second MatchExpression specifies the filename pattern *.html and identifies the WebLogic Cluster hosts and their ports. The paramName=value combination following the pipe symbol specifies the error page for the cluster.\n\nExample Using Multiple WebLogic Clusters\n\n```\n# These parameters are common for all URLs which are\ndirected to the current module. If you want to override\nthese parameters for each URL, you can set them again in\nthe <Location> or <Files> blocks (Except WebLogicHost,\nWebLogicPort, WebLogicCluster, and CookieName.)\n\n<IfModule mod_weblogic.c>\n MatchExpression *.jsp WebLogicHost=myHost|WebLogicPort=7001|Debug=ON\n</IfModule>\n```\n\nExample Without WebLogic Clusters\n\n```\n# These parameters are common for all URLs which are\ndirected to the current module. If you want to override\nthese parameters for each URL, you can set them again in\nthe <Location> or <Files> blocks (Except WebLogicHost,\nWebLogicPort, WebLogicCluster, and CookieName.)\n<IfModule mod_weblogic.c>\n WebLogicHost myweblogic.server.com\n WebLogicPort 7001\n MatchExpression *.jsp\n</IfModule>\n```\n\nExample Configuring Multiple Name-Based Virtual Hosts\n\n```\n# VirtualHost1 = localhost:80\n<VirtualHost 127.0.0.1:80>\n DocumentRoot \"C:/test/VirtualHost1\"\n ServerName localhost:80\n <IfModule mod_weblogic.c>\n #... WLS parameter ...\n WebLogicCluster localhost:7101,localhost:7201\n # Example: MatchExpression *.jsp <some additional parameter>\n MatchExpression *.jsp PathPrepend=/test2\n </IfModule>\n</VirtualHost>\n\n# VirtualHost2 = 127.0.0.2:80\n<VirtualHost 127.0.0.2:80>\n DocumentRoot \"C:/test/VirtualHost1\"\n ServerName 127.0.0.2:80\n <IfModule mod_weblogic.c>\n #... WLS parameter ...\n WebLogicCluster localhost:7101,localhost:7201\n # Example: MatchExpression *.jsp <some additional parameter>\n MatchExpression *.jsp PathPrepend=/test2\n #... WLS parameter ...\n </IfModule>\n</VirtualHost>\n```\nYou must define a unique value for `ServerName` or some plug-in parameters will not work as expected.\n\n### 3.3.4.3 Template for the Apache HTTP Server httpd.conf File\n\nThis section contains a sample `httpd.conf` file for Apache HTTP Server. You can use this sample as a template and modify it to suit your environment and server. Lines beginning with `#` are comments.\n\n---\n\n**Note:**\n\nApache HTTP Server is not case sensitive.\n\n---\n\nSample `httpd.conf` file for Apache HTTP Server\n\n```plaintext\nLoadModule weblogic_module /home/myhome/weblogic-plugins-12.2.1/lib/mod_wl.so\n\n<Location /weblogic>\n WLSRequest On\n PathTrim /weblogic\n ErrorPage http://myerrorpagel.mydomain.com\n</Location>\n\n<Location /servletimages>\n WLSRequest On\n PathTrim /something\n ErrorPage http://myerrorpagel.mydomain.com\n</Location>\n\n<IfModule mod_weblogic.c>\n MatchExpression *.jsp\n WebLogicCluster w1s1.com:7001,w1s2.com:7001,w1s3.com:7001\n ErrorPage http://myerrorpage.mydomain.com\n</IfModule>\n```\n\n### 3.4 Understanding DMS Metrics for Apache HTTP Server Plug-in\n\nYou can configure and view DMS performance metrics for Apache HTTP Server. The Apache HTTP server provides the same set of DMS metrics as the Oracle WebLogic Server.\n\nThe DMS metrics that can be returned are described in DMS State Metrics, DMS Event Metrics, and DMS PhaseEvent Metrics.\n\nThis section contains the following information:\n\n- Configuring Metrics DMS Metrics for Apache HTTP Server Plug-in\n- Viewing Performance Metrics for Apache HTTP Server Plug-in\n\n#### 3.4.1 Configuring Metrics DMS Metrics for Apache HTTP Server Plug-in\n\nTo configure DMS metrics for the Apache HTTP Server, add the following code to the `httpd.conf` file.\nAdd the following LoadModule only if it is not already present\n\n```\n# Use mod_wl.so for Apache httpd 2.2\nLoadModule weblogic_module $PLUGIN_HOME/mod_wl_24.so\n```\n\n```\n<Location /metrics>\n SetHandler dms-handler\n</Location>\n```\n\n3.4.2 Viewing Performance Metrics for Apache HTTP Server Plug-in\n\nYou can view the raw metrics using the URL:\n\n```\nhttp://apachehost:apacheport/metrics\n```\n\nwhere `apachehost` is the host name of the Apache server and `apacheport` is the port number.\n\nThe metrics that are coming from Oracle WebLogic Server plug-in can be found under the section `/WebLogicProxy [type=OHSWebLogic]`.\n\n3.5 Deprecated Directives for Apache HTTP Server\n\nThe WebLogic Server plug-in logs are now part of the Apache HTTP Server error log. References can be identified with the prefix `weblogic:` to easily identify them, for example:\n\nApache 2.4 example:\n\n```\n```\n\nApache 2.2 example:\n\n```\n```\n\nThe directives `WLLogFile` and `Debug` are deprecated. If the configuration uses these directives, the following note will appear during startup:\n\n```\n[Thu May 14 23:22:19 2015] [warn] weblogic: The Debug directive is ignored. The web server log level is used instead.\n```\n\nTo enable plug-in logs, set `LogLevel` to `debug`. The logs will be included in the file pointed to by the `ErrorLog` directive.\n4\n\nConfiguring the Plug-In for iPlanet Web Server\n\nThis chapter describes how to install and configure the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server. In previous releases, this plug-in was referred to as the Netscape Enterprise Server plug-in.\n\nThis chapter contains the following sections:\n\n- Overview of the Oracle WebLogic Server Proxy Plug-In for iPlanet\n- Installing and Configuring the Plug-In for iPlanet\n- Deprecated Directives for iPlanet Web Server\n\n4.1 Overview of the Oracle WebLogic Server Proxy Plug-In for iPlanet\n\nThe Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server enables requests to be proxied from Oracle iPlanet Web Server to Oracle WebLogic Server. The plug-in enhances an Oracle iPlanet Web Server installation by allowing Oracle WebLogic Server to handle those requests that require the dynamic functionality of the server.\n\nThe Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server is designed for an environment where Oracle iPlanet Web Server serves static pages, and an Oracle WebLogic Server instance (operating in a different process, possibly on a different machine) is delegated to serve dynamic pages, such as JSPs or pages generated by HTTP Servlets. The connection between WebLogic Server and the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server is made using clear text or Secure Sockets Layer (SSL). To the end user—the browser—the HTTP requests delegated to WebLogic Server appear to come from the same source as the static pages. Additionally, the HTTP-tunneling facility of WebLogic Server can operate through the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server, providing access to all WebLogic Server services (not just dynamic pages).\n\nThe Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server operates as a module within an Oracle iPlanet Web Server. The module is loaded at startup and later based on the configuration, certain HTTP requests are delegated to it.\n\nFor more information about Oracle iPlanet Web Server see, http://download.oracle.com/docs/cd/E18958_01/doc.70/e18789/chapter.htm\n\n4.2 Installing and Configuring the Plug-In for iPlanet\n\nThe following sections provide information pertaining to the installation prerequisites and configuring the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server.\n\n- Installation Prerequisites\n• Installing the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server\n• Configuring the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server\n• Example: Configuring the iPlanet Plug-in\n• Guidelines for Modifying the obj.conf File\n• Sample obj.conf File (Not Using a WebLogic Cluster)\n\n4.2.1 Installation Prerequisites\n\nBefore you install the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server, complete these installation and verification tasks.\n\n• Create a plug-in zip extract location (PLUGIN_HOME; for example, /home/myhome/weblogic-plugins-12.2.1/)\n\n• Download the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server, as described in Availability of Oracle WebLogic Server Proxy Plug-In.\n\n• Extract the plug-in zip distribution into the Web Server installation directory install-dir. Before extracting the plug-in zip distribution, rename the existing README.txt within install-dir. This distribution contains these files:\n\n<table>\n<thead>\n<tr>\n<th>(path)/filename</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>README.txt</td>\n<td>information specific to the distribution, late-breaking updates, and other errata.</td>\n</tr>\n<tr>\n<td>bin/orapki (.bat on Windows)</td>\n<td>orapki tool for configuring Oracle wallets</td>\n</tr>\n<tr>\n<td>jlib/*.jar</td>\n<td>orapki helper Java libraries</td>\n</tr>\n<tr>\n<td>lib/mod_wl.so</td>\n<td>WebLogic proxy module</td>\n</tr>\n<tr>\n<td>lib/*.so</td>\n<td>Helper libraries</td>\n</tr>\n</tbody>\n</table>\n\n• Install JDK 8 to use SSL. You must have a JDK 8 installation to use the orapki utility. The orapki utility manages public key infrastructure (PKI) elements, such as wallets and certificate revocation lists, for use with SSL.\n\n• Create a supported Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server installation (7.0.9 or later) installed on IPLANET_HOME; that is, iPlanet server listening on iplanet-host:iplanet-port.\n\nThe version 12c (12.2.1.1.0) plug-in is supported on the Oracle WebLogic Server Proxy Plug-In 12c (12.2.1.1.0) for iPlanet Web Server platforms described in: http://www.oracle.com/technology/software/products/ias/files/fusion_certification.html\n\n• Create an iPlanet instance location (INSTANCE-DIR; for example, $ {IPLANET_HOME}/https-foo.\n• Create a supported version of WebLogic Server is configured and running on a\ntarget system. This server does not need to run on the system to which you\nextracted the plug-in zip distribution. For the supported WebLogic Server versions,\nsee:\n\nfusion_certification.html\n\n4.2.2 Installing the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server\n\nThe Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server is distributed as a\nshared object (.so).\n\nTo instruct Oracle iPlanet Web Server to load the native library (mod_wl.so) as a\nmodule, add the following line to the magnus.conf file.\n\nInit fn=\"load-modules\" shlib=\"mod_wl.so\"\n\nThe magnus.conf file is located in the INSTANCE-DIR/config directory. Where\nINSTANCE-DIR is the web server instance directory. For more information, see:\n\nhttp://download.oracle.com/docs/cd/\nE19146-01/821-1827/821-1827.pdf\n\n4.2.3 Configuring the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server\n\nThis section provides information about configuring the Oracle WebLogic Server\nProxy Plug-In for iPlanet Web Server. To do this, you configure the obj.conf file. the\nobj.conf file defines which requests are proxied to WebLogic Server and other\nconfiguration information.\n\n1. Locate and open the obj.conf file\n\nThe default obj.conf file is located in the INSTANCE-DIR/config directory. Where\nINSTANCE-DIR is the web server instance directory. For more information, see\n\nhttp://download.oracle.com/docs/cd/\nE19146-01/821-1827/821-1827.pdf\n\n2. Configure the obj.conf file.\n\nThere are different ways to configure obj.conf file. See the guidelines described in\nGuidelines for Modifying the obj.conf File.\n\n4.2.3.1 Proxying Requests by URL\n\nTo proxy requests by URL (also called proxying by path,) create a separate <Object>\ntag for each URL that you want to proxy and define the PathTrim parameter. The\nfollowing is an example of an <Object> tag that proxies a request containing the\nstring */weblogic/*\n\n<Object ppath=\"/weblogic/*\"\nService fn=wl-proxy WebLogicHost=myserver.com WebLogicPort=7001 PathTrim=\"/weblogic\"\n</Object>\n\nHere is an example of the object definitions for two separate ppaths that identify\nrequests to be sent to different instances of WebLogic Server:\n\n<Object ppath=\"/weblogic/*\"\nService fn=wl-proxy WebLogicHost=myserver.com WebLogicPort=7001 PathTrim=\"/weblogic\"\n</Object>\nNote:\nParameters that are not required, such as PathTrim, can be used to further configure the way the ppath is passed through the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server. For a complete list of plug-in parameters, see General Parameters for Web Server Plug-Ins.\n\n4.2.3.2 Proxying the Request by MIME Type\n\nIf you are proxying requests by MIME type, add any new MIME types referenced in the obj.conf file to the mime.types file. You can add MIME types by using the iPlanet server console or by editing the mime.types file directly.\n\n- To directly edit mime.types file, open the file for editing and type the following line:\n \n type=text/jsp exts=jsp\n\n- To edit the mime.types file in the iPlanet Administration console, see [http://download.oracle.com/docs/cd/E19146-01/821-1828/gdabr/index.html](http://download.oracle.com/docs/cd/E19146-01/821-1828/gdabr/index.html)\n\nNote:\niPlanet Web Server 7.0.9 and above already defines the MIME type for JSPs. Change the existing MIME type from magnus-internal/jsp to text/jsp.\n\nAll requests with a designated MIME type extension (for example, .jsp) can be proxied to the WebLogic Server, regardless of the URL.\n\nFor example, to proxy all JSPs to a WebLogic Server, the following Service directive should be added:\n\n```\nService method=\"(GET|HEAD|POST|PUT)\" type=text/jsp fn=wl-proxy\nWebLogicHost=myserver.com WebLogicPort=7001 PathPrepend=/jspfiles\n```\n\nThis Service directive proxies all files with the .jsp extension to the designated WebLogic Server, where they are served with a URL like this:\n\n```\nhttp://myserver.com:7001/jspfiles/myfile.jsp\n```\n\nThe value of the PathPrepend parameter should correspond to the context root of a Web Application that is deployed on the WebLogic Server or cluster to which requests are proxied.\n\nAfter adding entries for the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server, the default `<Object>` definition will be similar to the following example:\n\n```\n<Object name=\"default\">\n AuthTrans fn=\"match-browser\" browser=\"*MSIE*\" ssl-unclean-shutdown=\"true\"\n NameTrans fn=\"pfx2dir\" from=\"/mc-icons\" dir=\"/export/home/ws/lib/icons\" name=\"es-internal\"\n PathCheck fn=\"uri-clean\"\n</Object>\n```\nYou can add a similar Service statement to the default object definition for all other MIME types that you want to proxy to WebLogic Server.\n\nFor proxy-by-MIME to work properly you must disable Java from the Oracle WebLogic Server Proxy Plug-In 12c (12.2.1.1.0) for iPlanet Web Server otherwise, SUN One will try to serve all requests that end in *.jsp and will return a 404 error as it will fail to locate the resource under $doc_root.\n\nTo disable Java from the Oracle iPlanet Web Server, comment out the NameTrans line that appears under name=\"default\" in the obj.conf file. Then, restart the web server.\n\nAs an alternative, you can do the following:\n\n• If you are proxying by path, enable HTTP-tunneling.\n\nIf you are using weblogic.jar and tunneling the t3 protocol, add the following object definition to the obj.conf file, substituting the WebLogic Server host name and the WebLogic Server port number, or the name of a WebLogic Cluster that you want to handle HTTP tunneling requests.\n\n```\n<Object name=\"tunnel\" ppath=\"*/HTTPClnt*\">\n Service fn=wl-proxy WebLogicHost=myserver.com WebLogicPort=7001\n</Object>\n```\n\n• If you are tunneling IIOP, which is the only protocol used by the WebLogic Server thin client, wlclient.jar, add the following object definition to the obj.conf file, substituting the WebLogic Server host name and the WebLogic Server port number, or the name of a WebLogic Cluster that you want to handle HTTP tunneling requests.\n\n```\n<Object name=\"tunnel\" ppath=\"*/iiop*/\">\n Service fn=wl-proxy WebLogicHost=myserver.com WebLogicPort=7001\n</Object>\n```\n\n4.2.3.3 Testing the Plug-in\n\nTo test the Oracle iPlanet Web Server plug-in, follow these steps:\n\n1. Start WebLogic Server.\n\n2. Start Oracle iPlanet Web Server. If Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server is already running, you must either restart or reconfigure the server.\n\n3. You can test the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server using the following URL. It should start the default WebLogic Server HTML page,\nwelcome file, or default servlet, as defined for the default Web Application as shown in this example\n\nhttp://webserver_host:webserver_port/weblogic/\n\nFor information on how to create a default Web Application, see Developing Web Applications, Servlets, and JSPs for Oracle WebLogic Server\n\n4.2.4 Example: Configuring the iPlanet Plug-in\n\nThe following example demonstrates basic instructions for quickly setting up the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server to proxy requests to a backend WebLogic Server (WLS).\n\n1. Edit $IPLANET_INSTANCE_HOME/config/magnus.conf file and add the following:\n\n ... \n Init fn=\"load-modules\" shlib=\"$PLUGIN_HOME/lib/mod_wl.so\"\n ...\n\n2. Open the $IPLANET_INSTANCE_HOME/config/ vs-obj.conf file (the default is $IPLANET_INSTANCE_HOME/config/obj.conf) and add the following code:\n\n ...\n <Object name=\"weblogic\" ppath=\"*/wls/*\">\n Service fn=\"wl-proxy\" WebLogicHost=<wls-host> WebLogicPort=<wls-port>\n DebugConfigInfo=\"ON\"\n PathTrim=\"/wls\"\n </Object>\n ...\n\n For more information on configuring the contents of obj.conf, see Sample obj.conf File (Not Using a WebLogic Cluster) and Sample obj.conf File (Using a WebLogic Cluster).\n\n3. At the prompt, include the $PLUGIN_HOME/lib in the LD_LIBRARY_PATH by entering:\n\n set LD_LIBRARY_PATH=/home/user/weblogic-plugin-12.2.1/lib:..\n\n Note:\n You can also update the LD_LIBRARY_PATH by copying the 'lib' contents to $IPLANET_HOME/lib or editing the $IPLANET_INSTANCE_HOME/bin/startserv.\n\n4. At the prompt, start the iPlanet server by entering:\n\n $IPLANET_INSTANCE_HOME/bin/startserv\n\n5. Send a request to http://iplanet-host:iplanet-port/mywebapp/my.jsp from the browser and validate the response.\n\n4.2.5 Guidelines for Modifying the obj.conf File\n\nTo use the Oracle WebLogic Server Proxy Plug-In for iPlanet Web Server, you must make several modifications to the obj.conf file. For more information, see\n4.2.6 Sample obj.conf File (Not Using a WebLogic Cluster)\n\nThe following code is an example of lines that should be added to the obj.conf file if you are not using a cluster. You can use this example as a template that you can modify to suit your environment and server. Lines beginning with # are comments.\n\n- **Proxy requests by URL**\n\n```xml\n## --------------BEGIN SAMPLE obj.conf CONFIGURATION---------\n# (no cluster)\n# Configure which types of HTTP requests should be handled by the\n# iPlanet NSAPI plug-In (and, in turn, by WebLogic). This is done\n# with one or more \"<Object>\" tags as shown below.\n# Here we configure the iPlanet plug-In module to pass requests for\n# */weblogic* to a WebLogic Server listening at port 7001 on\n# the host myweblogic.server.com.\n<Object ppath=\"*/weblogic/*\">\n Service fn=wl-proxy WebLogicHost=myweblogic.server.com WebLogicPort=7001\n PathTrim=\"/weblogic*\"\n</Object>\n# Here we configure the plug-in so that requests that\n# match */servletimages/* is handled by the\n# plug-in/WebLogic.\n<Object name=\"si\" ppath=\"*/servletimages/*\">\n Service fn=wl-proxy WebLogicHost=myweblogic.server.com WebLogicPort=7001\n</Object>\n## -------------END SAMPLE obj.conf CONFIGURATION-------------------\n```\n\n- **Proxy requests by MIME type**\n\nThis Object directive works by file extension rather than\nrequest path. To use this configuration, you must modify the existing line or add the following line to mime.types file.\n\n```xml\n## -----------BEGIN SAMPLE mime.types CONFIGURATION---------------------\n# type=text/jsp exts=jsp\n## ------------END SAMPLE mime.types CONFIGURATION----------------------\n## -------------BEGIN SAMPLE obj.conf CONFIGURATION---------------------\n# This configuration means that any file with the extension\n# \".jsp\" are proxied to WebLogic. Then you must add the\n# Service line for this extension to the Object \"default\",\n# which should already exist in your obj.conf file:\n<Object name=default>\n NameTrans fn=pfx2dir from=/ns-icons dir=\"c:/Export/Home/ns-icons\"\n NameTrans fn=pfx2dir from=/mc-icons dir=\"c://Export/Home/ns-icons\"\n NameTrans fn=pfx2dir from=/help* dir=\"c://Export/Home/manual/https/ug\"\n NameTrans fn=document-root root=\"c:/Export/Home/docs\"\n Service method=\"(GET|HEAD|POST|PUT)\" type=text/jsp fn=wl_proxy\n WebLogicHost=myweblogic.server.com WebLogicPort=7001 PathPrepend=/jspfiles\n PathCheck fn=nt-uri-clean\n PathCheck fn=\"check-acl\" acl=\"default\"\n PathCheck fn=find-pathinfo\n ObjectType fn=type-by-extension\n ObjectType fn=force-type type=text/plain\n Service method=\"(GET|HEAD)\" type=magnus-internal/imagemap fn=imagemap\n</Object>\n```\n\n4.2.7 Sample obj.conf File (Using a WebLogic Cluster)\n\nThe following code is an example of lines that should be added to obj.conf if you are using a WebLogic Server cluster. You can use this example as a template that you can modify to suit your environment and server. Lines beginning with # are comments.\n\n- Proxy requests by URL\n\n```\n## -----------------BEGIN SAMPLE obj.conf CONFIGURATION------------------\n# (using a WebLogic Cluster)\n#\n# Configure which types of HTTP requests should be handled by the\n# iPlanet module (and, in turn, by WebLogic). This is done\n# with one or more \"<Object>\" tags as shown below.\n# Here we configure the iPlanet module to pass requests for\n# \"/weblogic\" to a cluster of WebLogic Servers.\n<Object ppath=\"*/weblogic/*\">\n Service fn=wl-proxy WebLogicCluster=\"myweblogic.com:7001,yourweblogic.com:7001,\n theirweblogic.com:7001\" PathTrim=\"/weblogic\"\n</Object>\n# Here we configure the plug-in so that requests that\n# match \"/servletimages/\" are handled by the\n# plug-in/WebLogic.\n<Object name=\"si\" ppath=\"*/servletimages/*\">\n Service fn=wl-proxy WebLogicCluster=\"myweblogic.com:7001,yourweblogic.com:7001,\n theirweblogic.com:7001\"\n</Object>\n## -----------------END OF SAMPLE obj.conf CONFIGURATION------------------\n```\n\n- Proxy requests by MIME types\n\n```\n# This Object directive works by file extension rather than\n# request path. To use this configuration, you must modify the existing line or\n# add the following line to mime.types file.: \n## -----------------BEGIN SAMPLE mime.types FILE -----------------------\n# type=text/jsp exts=jsp \n## -----------------END SAMPLE mime.types FILE------------------------\n```\n\n```\n## -----------------BEGIN SAMPLE obj.conf CONFIGURATION------------------\n# This configuration means that any file with the extension\n# \".jsp\" is proxied to WebLogic. Then you must add the\n# Service line for this extension to the Object \"default\",\n# which should already exist in your obj.conf file: \n<Object name=\"default\">\n NameTrans fn=\"pfx2dir\" from=\"/help\" dir=\"c://Export/Home/manual/https/ug\"\n NameTrans fn=document-root root=\"/c://Export/Home/docs\"\n</Object>\n```\n\n```\n## -----------------END SAMPLE obj.conf CONFIGURATION------------------\n```\n4.3 Deprecated Directives for iPlanet Web Server\n\nThe WebLogic Server plug-in logs are now part of the Oracle iPlanet Server error log. References can be identified with the prefix weblogic: to easily identify them, for example:\n\n```\n[14/May/2015:23:18:34] fine (21904): for host 10.184.61.77 trying to GET /wls/testcluster, wl-proxy reports: <2190414316707144> weblogic: After trimming path: '/' testcluster\n```\n\nThe directives WLLogFile and Debug are deprecated. If the configuration uses these directives, the following note will appear:\n\n```\n```\n\nTo enable plug-in logs, set log-level to fine.\nConfiguring the Plug-In for Microsoft IIS Web Server\n\nThe following sections describe how to install and configure the Oracle WebLogic Server Proxy Plug-In for Microsoft IIS Web Server:\n\n- **Working with the Microsoft IIS 7.0 Plug-In**\n- **Working with the Microsoft IIS 7.5 Plug-In**\n\nDownload the Oracle WebLogic Server Proxy Plug-In for IIS Web Server, as described in *Availability of Oracle WebLogic Server Proxy Plug-In*. The zip file contains these files:\n\n<table>\n<thead>\n<tr>\n<th>(path)/filename</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>README.txt</td>\n<td>Information specific to the distribution, late-breaking updates, and other errata.</td>\n</tr>\n<tr>\n<td>bin/orapki.bat</td>\n<td>orapki tool for configuring Oracle wallets</td>\n</tr>\n<tr>\n<td>jlib/*.jar</td>\n<td>orapki helper Java libraries</td>\n</tr>\n<tr>\n<td>iiisproxy.dll</td>\n<td>WebLogic proxy module</td>\n</tr>\n<tr>\n<td>lib/*.dll</td>\n<td>Helper libraries</td>\n</tr>\n</tbody>\n</table>\n\n### 5.1 Working with the Microsoft IIS 7.0 Plug-In\n\nThis section describes how to install and configure the plug-in for Microsoft IIS 7.0.\n\n- **Installing and Configuring the Microsoft IIS 7.0 Plug-In**\n- **Serving Static Files from the Web Server**\n- **Using Wildcard Application Mappings to Proxy by Path**\n- **Proxying Requests from Multiple Virtual Web Sites to WebLogic Server**\n- **Creating ACLs Through IIS 7.0**\n- **Testing the Installation**\n\n#### 5.1.1 Installing and Configuring the Microsoft IIS 7.0 Plug-In\n\nThis section describes how to set up the Microsoft Internet Information Server plug-in for IIS 7.0.\nTo set up the Microsoft Internet Information Server plug-in for IIS 7.0, follow these steps:\n\n1. Download and install Microsoft IIS 7.0.\n2. Ensure that all of the necessary features of Microsoft IIS 7.0 are enabled.\n3. Download and install the latest Oracle WebLogic Server Proxy Plug-In zip file.\n4. Create a web application in IIS Manager by right clicking on Web Sites > Add Web Site.\n\n Fill in the Web Site Name with the name you want to give to your web application; for example, MyApp. Select the physical path of your web application Port (any valid port number not currently in use).\n\n Click OK to create the web application.\n\n If you can see the name of your application under Web Sites it means that your application has been created and started running. Click the MyApp node under Web Sites to see all of the settings related to the MyApp application, which you can change, as shown in Figure 5-1.\n\n **Figure 5-1 Application Home Page**\n\n5. Click Handler Mappings to set the mappings to the handler for a particular MIME type.\n6. Click the StaticFile and change the Request path from * to *. Click **OK**.\n7. Click **MyApp** and then click **Add Script Map** on the right-hand side menu options. Enter * for the Request path.\n\nBrowse to the iisproxy.dll file and add it as the executable. Name it **proxy**.\n8. Click Request Restrictions and deselect Invoke handler only if the request is mapped to.\n9. Click **OK** to add this Handler mapping. Click **Yes** on the Add Script Map dialog box.\nTo configure proxying by path, see Using Wildcard Application Mappings to Proxy by Path.\n\n11. Click the Root node of the IIS Manager tree and click the ISAPI and CGI Restrictions. Make sure to check Allow unspecified ISAPI modules.\n12. Create a file called iisproxy.ini with the following contents and place it in the\n directory with the plug-in:\n\n WebLogicHost = @hostname@\n WebLogicPort = @port@\n ConnectRetrySecs = 5\n ConnectTimeoutSecs = 25\n Debug = ALL\n DebugConfigInfo = ON\n KeepAliveEnabled = true\n WLLogFile = @Log file name@\n SecureProxy = OFF\n\n You should be able to see the Medrec Sample Application from your Oracle\n WebLogic Server.\n\n To run the plug-in SSL mode, change the value of WeblogicPort to the SSL port of\n your application, change the SecureProxy value to ON, and set WLSSLWallet to\n the location of the wallet. For more information on SSL parameters, see SSL\n Parameters for Web Server Plug-Ins.\n5.1.2 Serving Static Files from the Web Server\n\nFollow these steps to have IIS serve all static content that could be included on a web application that is to be served by WebLogic Server.\n\n1. Configure your application by setting up Oracle WebLogic Server Proxy Plug-In for Microsoft IIS Web Server on IIS Web Server as described in Installing and Configuring the Microsoft IIS 7.0 Plug-In.\n\nAssume that you created a Handler Mapper named proxy as described in the Oracle documentation.\n\n**Note:**\nDo not use `WLEXCLUDEPATHORMIMETYPE` property inside your proxy setup. It is not required neither useful here and can only confuse the understanding of the flow.\n\n2. In IIS Manager, display the home page by clicking the Virtual Directory or Application created in Step 1.\n\n3. Double-click the Handling Mappers and then click View Ordered List on the right side pane. An ordered list of Handler Mappings appears.\n\n4. Select `proxy` and drag it below StaticFile handler mapping (in other words the StaticFile handler mapping should appear above the proxy handler mapping.)\n\n5. Edit the Static File and change the request path to: *.jpg. Save the file.\n\n6. Configure IIS to serve types of static files, for example, PNGs, GIFs, or CSS files.\n a. On IIS Manager, display the home page by clicking the Virtual Directory or Application created in Step 1.\nb. Double click the Handling Mappers and then click Add Module Mapping on the right side pane.\n\nc. Choose a Request Path of desired type: for PNGs use *.png, for GIFs use *.gif and so on. For Module, choose StaticFileModule, enter a name, and click OK.\n\nd. Ensure that as stated in step 4, the newly created HandlerMapping is ordered before the proxy Handler Mapping defined in Step 1.\n\n### 5.1.3 Using Wildcard Application Mappings to Proxy by Path\n\nYou can configure a website or virtual directory to run an Internet Server API (ISAPI) application at the beginning of every request to that website or virtual directory, regardless of the extension of the requested file. You can use this feature to insert a mapping to iisproxy.dll and thereby proxy requests by path to WebLogic Server.\n\n#### 5.1.3.1 Adding a Wildcard Script Map for IIS 7.0 and Above\n\nThe following steps summarize the instructions available at “Add a Wildcard Script Map” for IIS [http://technet.microsoft.com/en-us/library/cc754606(WS.10).aspx] to add a wildcard script map to do proxy-by-path with ISAPI in IIS:\n\n1. Open IIS Manager and navigate to the level you want to manage.\n\n For information about opening IIS Manager, see \"Open IIS Manager\" at [http://technet.microsoft.com/en-us/library/cc770472(WS.10).aspx].\n\n For information about navigating to locations in the UI, see \"Navigation in IIS Manager\" at [http://technet.microsoft.com/en-us/library/cc732920(WS.10).aspx].\n\n2. In Features View, on the server, site, or application Home page, double-click Handler Mappings.\n\n3. On the Handler Mappings page, in the Actions pane, click Add Wildcard Script Map.\n\n4. In the Executable box, type the full path or browse to the iisproxy.dll that processes the request. For example, type systemroot\\system32\\inetsrv\\iisproxy.dll.\n\n5. In the Name box, type a friendly name for the handler mapping.\n\n6. Click OK.\n\n7. Optionally, on the Handler Mappings page, select a handler to lock or unlock. When you lock a handler mapping, it cannot be overridden at lower levels in the configuration. Select a handler mapping in the list, and then in the Actions pane, click Lock or Unlock.\n\n8. After you add a wildcard script map, you must add the executable to the ISAPI and CGI Restrictions list to enable it to run. For more information about ISAPI and CGI restrictions, see \"Configuring ISAPI and CGI Restrictions in IIS 7\" at [http://technet.microsoft.com/en-us/library/cc730912(WS.10).aspx].\nNote:\n\nIf you are proxying a request to multiple IIS applications within the same IIS site, to prevent the subsequent request from proxying to the first website only, create each IIS application and assign a unique application pool to each IIS application.\n\nWith IIS 7.x, you cannot assign application pools to virtual directories.\n\n5.1.4 Proxying Requests from Multiple Virtual Web Sites to WebLogic Server\n\nTo proxy requests from multiple websites (defined as virtual directories in IIS) to WebLogic Server:\n\n1. Create a new directory for the virtual directories. This directory will contain .dll and .ini files used to define the proxy.\n2. Extract the contents of the plug-in .zip file to a directory.\n3. For each virtual directory you configured, copy the contents of the plug-in \\lib folder to the directory you created in step 1.\n4. Create an iisproxy.ini file for the virtual websites, as described in Sample iisproxy.ini File. Copy this iisproxy.ini file to the directory you created in Step 1.\n5. Copy iisproxy.dll to the directory you created in Step 1.\n6. Create a separate application pool for each virtual directory.\n\nAs described in \"Creating Application Pools (IIS 6.)\" (http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/93275ef2-2f85-4eb1-8b92-a67545be11b4.mspx?mfr=true), you can isolate different Web applications or websites in pools, which are called application pools. In an application pool, process boundaries separate each worker process from other worker processes so that when an application is routed to one application pool, applications in other application pools do not affect that application.\n\nNote:\n\nStep 6 only applies to IIS 6.0 as there is no Application Protection option with IIS 7.0. This step will work with IIS 7.0, except that exactly one IIS virtual directory exists within a particular IIS site. The limitation exists because, with IIS 7.0, it is impossible to assign a unique application pool to each virtual directory, thus the subsequent requests are always proxied to the first website (virtual directory).\n\n5.1.4.1 Sample iisproxy.ini File\n\nThe following sample iisproxy.ini file can be used with a single, non-clustered WebLogic Server. Comment lines are denoted with the \"#\" character.\n\n# This file contains initialization name/value pairs\n# for the IIS/WebLogic plug-in.\nWebLogicHost=localhost\nWebLogicPort=7001\nConnectTimeoutSecs=20\nConnectRetrySecs=2\n\nThe following sample iisproxy.ini file can be used with clustered WebLogic Servers. Comment lines are denoted with the \"#\" character.\n\n# This file contains initialization name/value pairs\n# for the IIS/WebLogic plug-in.\nWebLogicCluster=myweblogic.com:7001,yourweblogic.com:7001\nConnectTimeoutSecs=20\nConnectRetrySecs=2\n\n---\n\n**Note:**\n\nIf you are using SSL between the plug-in and WebLogic Server, the port number should be defined as the SSL listen port.\n\n---\n\n### 5.1.5 Creating ACLs Through IIS 7.0\n\nACLs will not work through the Oracle WebLogic Server Proxy Plug-In 12c (12.2.1.1.0) for Microsoft IIS Web Server if the Authorization header is not passed by IIS. Use the following information to ensure that the Authorization header is passed by IIS.\n\n1. Ensure that the user is logged on with local log-on rights when using Basic Authentication.\n\n2. Grant each user account the Log On Locally user right on the IIS server. To enable the use of Basic Authentication, two problems may result from Basic Authentication’s use of local logon:\n\n - If the user does not have local logon rights, Basic Authentication does not work even if the FrontPage, IIS, and Windows NT configurations appear to be correct.\n - A user who has local log-on rights and who can obtain physical access to the host computer running IIS will be permitted to start an interactive session at the console.\n\n3. To enable Basic Authentication, in the Directory Security tab of the console, ensure that the Allow Anonymous option is \"on\" and all other options are \"off\".\n\n### 5.1.6 Testing the Installation\n\nFollow these steps to ensure that the Microsoft IIS plug-in has been installed, configured, and deployed successfully.\n\n1. Make sure WebLogic Server and IIS are running.\n\n2. Save a JSP file into the document root of the default Web Application.\n\n3. Open a browser and set the URL to the IIS plus `filename.jsp`, as shown in this example:\n\n ```\n http://myiis.server.com/filename.jsp\n ```\n\n If `filename.jsp` is displayed in your browser, the plug-in is functioning.\n5.2 Working with the Microsoft IIS 7.5 Plug-In\n\nThis section describes how to install and configure the plug-in for Microsoft IIS 7.5.\n\n- Installing and Configuring the Microsoft IIS 7.5 Plug-In\n- Serving Static Files with IIS 7.5\n- Serving Static Files and Dynamic Content From the Same Request with IIS 7.5\n\n5.2.1 Installing and Configuring the Microsoft IIS 7.5 Plug-In\n\nFollow these steps to install and configure the Microsoft IIS 7.5 Plug-In.\n\n1. Install Microsoft IIS 7.5.\n\n2. Ensure that all of the necessary features of Microsoft IIS 7.5 are enabled.\n \n a. From the Start menu, choose Control Panel, then Programs and Features. Select Internet Information Services (IIS) 7+ Manager. Click Turn Windows features on or off.\n \n b. Expand the entire tree beneath Internet Information Services and ensure all of the subfeatures are selected.\n3. Download and install the latest Oracle WebLogic Server Proxy Plug-In zip file.\n\n4. Create an `iisproxy.ini` file with the following content in the `%PLUGIN_HOME%/lib` folder:\n\n ```\n WebLogicHost=URL_of_WebLogic_Host\n WebLogicPort=WebLogic_Port\n Debug=ALL\n DebugConfigInfo=ON\n WLLogFile=C:\\Temp\\wl-proxy.log\n ```\n\n5. Ensure that the `%PLUGIN_HOME%/lib` folder is included in the system PATH (select Control Panel, then System, then System Properties, then Environment Variables, then System Properties, then PATH).\n6. Open IIS Manager (select Start, then All Programs, then Administrative tools, then Internet Information Services Manager).\n\nFigure 5-10 Internet Information Services Manager Window\n\n7. Create a new Web Site in IIS. See the IIS Help system for more information.\n\n8. Click the site name, open Handler Mappings and add a script map (set the Extension to a value such as .jsp, set Executable to %PLUGIN_HOME%\\lib \\iiproxy.dll, and assign a value to Name).\n\n9. Click MIME Types and ensure a MIME type has been defined for the extension. Add the MIME type and its definition if it is not present.\n\n10. Click the site name, open Directory browsing and enable the feature.\n\n11. Start IIS (enter services.msc at the command prompt and go to \"World Wide Web Publishing Services\" at the bottom and restart it. Also restart the web site).\n12. Test your configuration by sending a request to `http://iishost:iisport/application_name/` from the browser and validate the response.\n\nHere, `iishost` is the URL of the IIS server and `iisport` is the port number. Note that the `iisport` number should be different from the port number of the WebLogic Server.\n\n### 5.2.2 Serving Static Files with IIS 7.5\n\nAfter configuring the WLS plug-in and confirming it works (see Installing and Configuring the Microsoft IIS 7.5 Plug-In) follow these steps to serve static files.\n\n1. Right click **Default web site** and then click **Add Virtual Directory**.\n\n2. In the **Alias** field enter `static` and set the physical path to the location of the static files, for example `c:\\inetpub\\wwwroot\\static`. Click **OK**. A **static** folder will appear under **Default Web Site**.\n\nNote: The physical path may be different in your case if the files are in a different location. Modify the path accordingly.\n3. Click static under Default Web Site to open the static Home page.\n\n4. On the static Home page click Handler Mappings and then click View Ordered List on the right-side pane. You will see an ordered list of Handler Mappings.\n\n5. Click Add Script Map. Set Request Path to \"/\", set Executable to \\%PLUGIN_HOME\\%lib\\iiproxy.dll, and assign the value proxy to Name. Click OK.\n\n6. Click View Ordered List to re-order the list of handlers.\n\n7. Click the proxy script map and move it down below the StaticFile handler mapping. (That means the StaticFile handler mapping should appear above the proxy handler mapping.)\n\n8. Create a static folder under c:\\inetpub\\wwwroot and copy an HTML file into it, for example index.html.\n\n9. Restart IIS 7.5 by restarting the \"World Wide Web Publishing Service\" under services (see Figure 5-11).\n\n\n5.2.3 Serving Static Files and Dynamic Content From the Same Request with IIS 7.5\n\nSuppose you want to serve the static files such as *.gif, *.png images for the request \"http://localhost:80/console\" from the IIS and other dynamic content from the backend WebLogic Server. Follow these steps in addition to Serving Static Files with IIS 7.5.\n\n1. Complete the steps described in the Serving Static Files with IIS 7.5.\n\n2. Right-click the \"Default web site\", then click \"Add Virtual Directory\", and then enter the following in the Add Virtual Directory dialog box.\n• **Alias**—console\n\n• **Physical Path**—C:\\path_to_the_wls_plug-in\\console\n\nIn this example, the physical path to the console is C:\\OHS_Plugin_IIS\\console.\n\nClick OK. You will see a \"console\" entry in the left pane under the Default Web Site.\n\n3. Click \"console\" under \"Default Web Site\". A \"console Home\" will open on the right side.\n\n4. Click \"Handler Mappings\" on the \"console Home\" pane\n\n5. Right-click **StaticFile** and select **Edit...**. Update the fields as follows in the Edit Module Mapping dialog box:\n - **Request Path**—*.png (that is, change \"*\" to \".png\")\n - **Module**—StaticFileModule, DefaultDocumentModule, DirectoryListingModule (should be the default)\n - **Executable**—not required. Leave it blank.\n - **Name**—StaticFile (it is not possible to change Name here)\n6. Click **Request Restrictions**. In the **Mapping** tab of the Request Restrictions dialog box, ensure that **Invoke Handler only if the request is mapped to** is selected, then select **File or Folder**. Click **OK** and **OK** to dismiss the dialog boxes.\n\nThe above step is to serve the *.png from the IIS server.\n7. To serve other image files, such as *.gif files, do the following.\n\n a. Under \"Console Home\" click \"Handler Mappings\", then click on \"Add Module Mapping\" on the right side and then enter the following.\n\n Request Path——*.gif \n Module——StaticFileModule, DefaultDocumentModule, DirectoryListingModule \n Executable—not required. Keep it blank \n Name——StaticFileForGIF\n\n b. Click \"Request Restrictions\". Under \"Mapping\" make sure the \"Invoke Handler only if the request is mapped to\" is selected and then select the \"File or Folder\" and then click \"OK\" and \"OK\"\n\n8. Arrange the order of the handlers.\n\n a. Click on \"console\" under \"Default web site\" and then click on \"Handler Mappings\" and then \"View Ordered List\" on the right side\n\n b. Select \"proxy\" and move it down till the \"proxy\" is below the \"StaticFile\" and \"StaticFileForGIF. That is, the order should be like below.\n\n StaticFile \n StaticFileForGIF \n proxy\n\n9. Copy all of the static files that belong to http://loclhost:<iis-port>/console request from WebLogic Server to IIS.\n\n10. Restart the service, then restart the web site.\n\n The images (*.png and *.gif) are now served by IIS and dynamic content by Weblogic server.\n\n For example, for the request http://localhost:80/console the images for console are served by the IIS and all other requests other than *.png and *.gif are served by Weblogic Server.\nThis chapter describes how to work with security for plug-ins. It contains the following sections:\n\n- Using SSL with Plug-Ins\n- Configuring SSL with the Plug-In for iPlanet Web Server.\n- Configuring Perimeter Authentication\n\n### 6.1 Using SSL with Plug-Ins\n\nYou can use the Secure Sockets Layer (SSL) protocol to protect the connection between the plug-in and Oracle WebLogic Server. The SSL protocol provides confidentiality and integrity to the data passed between the plug-in and WebLogic Server.\n\nThe plug-in does not use the transport protocol (HTTP or HTTPS) specified in the HTTP request (usually by the browser) to determine whether to use SSL to protect the connection between the plug-in and WebLogic Server; that is, the plug-in is in no way dependent on whether the HTTP request (again, usually from the browser) uses HTTPS (SSL).\n\nInstead, the plug-in uses SSL parameters that you configure for the plug-in, as described in SSL Parameters for Web Server Plug-Ins, to determine when to use SSL:\n\n- **WebLogicSSLVersion**—Specifies the SSL protocol version to use for communication between the plug-in and the WebLogic Server.\n\n- **WLSSLWallet**—The version 12c (12.2.1.1.0) plug-ins use Oracle wallets to store SSL configuration information. Use the WLSSLWallet SSL configuration parameter to configure the wallets. The orapki utility is provided in the plug-in distribution for this purpose.\n\n The orapki utility manages public key infrastructure (PKI) elements, such as wallets and certificate revocation lists, on the command line so the tasks it performs can be incorporated into scripts. This enables you to automate many of the routine tasks of maintaining a PKI.\n\n For more information, see \"Using the orapki Utility for Certificate Validation and CRL Management\".\n\n- **SecureProxy**—The SecureProxy parameter determines whether SSL is enabled.\n\n---\n\n**Note:**\n\nFor more information on valid security protocols and ciphers for the current release, see \"SSLCipherSuite\" and \"SSLProtocol\" in *Administering Oracle HTTP Server*. \nIn the case of two-way SSL, the plug-in (the SSL client) automatically uses two-way SSL when Oracle WebLogic Server is configured for two-way SSL and requests a client certificate.\n\nIf a client certificate is not requested, the plug-ins default to one-way SSL.\n\n---\n\n**Note:**\n\nIf an Oracle Fusion Middleware 12c (12.2.1.1.0) product is installed on the same system as the Apache (including Oracle HTTP Server) plug-in, the `ORACLE_HOME` variable must point to a valid installation; otherwise, the plug-in fails to initialize SSL.\n\nFor example, if `ORACLE_HOME` is invalid because the product was not cleanly removed, the plug-in fails to initialize SSL.\n\n---\n\nThis section contains the following information:\n\n- Configuring Libraries for SSL\n- Configuring a Plug-In for One-Way SSL\n- Configuring Two-Way SSL Between the Plug-In and Oracle WebLogic Server\n\n### 6.1.1 Configuring Libraries for SSL\n\nPlug-ins use Oracle libraries (NZ) to provide SSL support. Because the libraries are large, they are loaded only when SSL is needed. You must ensure that the library files, located in `lib/*.so*`, are available at the proper locations so that they can be dynamically loaded by the plug-in.\n\nTo configure the libraries for the plug-ins for Apache HTTP Server, you have a few options:\n\n- **Windows:** Specify the `lib` directory that contains the `.dll` files in the `PATH` variable or copy the `*.dll` files in the `bin` directory.\n- **UNIX:** Configure `LD_LIBRARY_PATH` to point to the folder containing the libraries or copy the libraries to the `lib` directory.\n\nIf you copy the libraries instead of updating the `PATH` (Windows) or `LD_LIBRARY_PATH` (UNIX) variables, you must copy the libraries afresh each time you install a new version of the plug-in.\n\n### 6.1.2 Configuring a Plug-In for One-Way SSL\n\nPerform the following steps to configure one-way SSL.\n\nIn these steps, you run the `keytool` commands on the system on which WebLogic Server is installed, and you run the `orapki` commands on the system on which the version 12c (12.2.1.1.0) plug-ins are installed.\n\n**Note:**\n\nThe examples in this section use the WebLogic Server demo CA. If you are using the plug-in in a production environment, ensure that trusted CAs are properly configured for the plug-in and for Oracle WebLogic Server.\n1. Configure Oracle WebLogic Server for SSL. For more information, see “Configuring SSL” in Administering Security for Oracle WebLogic Server.\n\n2. Create an Oracle Wallet, by using the orapki utility.\n\n orapki wallet create -wallet mywallet -auto_login_only\n\n For more information, see “Using the orapki Utility for Certificate Validation and CRL Management” in the Administering Oracle Fusion Middleware.\n\n **Note:**\n\n Only the user who creates the wallet (or for Windows, the account SYSTEM) has access to the wallet.\n\n This is typically sufficient for the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server because Apache runs as the account SYSTEM on Windows, and as the user who creates it on UNIX. However, for IIS the wallet will not work because the default user is IUSR_<Machine_Name> (IIS6.0 and below) or IUSR (IIS7.0 and above).\n\n If the user who runs the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server or Oracle WebLogic Server Proxy Plug-In 12c (12.2.1.1.0) for Microsoft IIS Web Server is different from the user who creates the wallet (or for Windows, the account SYSTEM), you need to grant the user access to the wallet by running the command `cacls` (Windows) or `chmod` (UNIX) after you create the wallet. For example:\n\n ```bash\n cacls <wallet_path>\\cwallet.sso /e /g IUSR:R\n ```\n\n3. Import the WLS trust certificate into the Oracle Wallet.\n\n orapki wallet add -wallet mywallet -trusted_cert -cert <cert_file_name> -auto_login_only\n\n4. Configure the web server configuration files as follows:\n\n • For Oracle HTTP Server, edit the `mod_wl_ohs.conf` file as follows:\n\n ```\n <IfModule mod_weblogic.c>\n WebLogicHost host\n WebLogicPort port\n SecureProxy ON\n WLSSLWallet path_to_wallet\n </IfModule>\n ```\n\n • For Microsoft IIS, edit the `iisproxy.ini` file as follows:\n\n ```\n WebLogicHost=host\n WebLogicPort=port\n SecureProxy=ON\n WLSSLWallet=path_to_wallet\n ```\n\n For more information about the parameters in these examples, see Parameters for Web Server Plug-Ins.\n\n5. Complete these steps if the version of the Oracle WebLogic Server instances in the back end is 10.3.4 (or a later release).\n\n a. Log in to the Oracle WebLogic Server administration console.\nb. In the Domain Structure pane, expand the **Environment** node.\n\n- If the server instances to which you want to proxy requests from Oracle HTTP Server are in a cluster, select **Clusters**.\n- Otherwise, select **Servers**.\n\nc. Select the server or cluster to which you want to proxy requests from Oracle HTTP Server.\n\nd. In the Configuration: General tab, scroll down to the Advanced section, then expand it.\n\ne. Do one of the following:\n\n<table>\n<thead>\n<tr>\n<th>To...</th>\n<th>Select...</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Enable one-way SSL</td>\n<td>WebLogic Plug-In Enabled</td>\n</tr>\n<tr>\n<td>Enable two-way SSL where client certificates are used to authenticate</td>\n<td>Client Cert Proxy Enabled</td>\n</tr>\n<tr>\n<td>Enable two-way SSL with client certificates.</td>\n<td>Both</td>\n</tr>\n</tbody>\n</table>\n\nf. If you selected **Servers** in Step 5.b, repeat steps 5.c and 5.d for the other servers to which you want to proxy requests from Oracle HTTP Servers.\n\ng. Click **Save**.\n\nFor the change to take effect, you must restart the server instances.\n\n6. Send a request to `http://host:port/mywebapp/my.jsp` from the browser and validate the response.\n\n### 6.1.3 Configuring Two-Way SSL Between the Plug-In and Oracle WebLogic Server\n\nWhen Oracle WebLogic Server is configured for two-way SSL, the plug-in forwards the user certificate to WebLogic Server. As long as WebLogic Server can validate the user certificate, two-way SSL can be established.\n\nIn addition to the steps described in Configuring a Plug-In for One-Way SSL, perform the following steps:\n\nIn these steps, you run the keytool commands on the system on which WebLogic Server is installed. You run the orapki commands on the system on which the version 12c (12.2.1.1.0) plug-ins are installed.\n\n1. From the Oracle wallet, generate a certificate request.\n\n2. Use this certificate request to create a certificate by using a CA or some other mechanism.\n\n3. Import the user certificate as a trusted certificate in the WebLogic trust store. Oracle WebLogic Server needs to trust the certificate.\n\n ```bash\n keytool -file user.crt -importcert -trustcacerts -keystore DemoTrust.jks -storepass <passphrase>\n ```\n4. Set the WebLogic Server SSL configuration options that require the presentation of client certificates (for two-way SSL). For more information, see \"Configure two-way SSL\" in the Oracle WebLogic Server Administration Console Online Help.\n\n6.2 Configuring SSL with the Plug-In for iPlanet Web Server\n\nYou can use the Secure Sockets Layer (SSL) protocol to protect the connection between the Oracle WebLogic Server Proxy Plug-In 12c (12.2.1.1.0) for iPlanet Web Server plug-in and Oracle WebLogic Server. The SSL protocol provides confidentiality and integrity to the data passed between the Oracle iPlanet Web Server plug-in and Oracle WebLogic Server.\n\nThe Oracle WebLogic Server Proxy Plug-In 12c (12.2.1.1.0) for iPlanet Web Server plug-in does not use the transport protocol (http or https) specified in the HTTP request (usually by the browser) to determine whether the SSL protocol will be used to protect the connection between the Oracle WebLogic Server Proxy Plug-In 12c (12.2.1.1.0) for iPlanet Web Server and Oracle WebLogic Server.\n\nTo use the SSL protocol between Oracle iPlanet Web Server plug-in and Oracle WebLogic Server:\n\n1. Configure Oracle WebLogic Server for SSL. For more information, see \"Configuring SSL\" in Administering Security for Oracle WebLogic Server.\n\n2. Set the WebLogicPort parameter in the Service directive in the obj.conf file to the listen port configured in Step 1.\n\n3. Set the SecureProxy parameter in the Service directive in the obj.conf file to ON.\n\n4. Set additional parameters, as required, in the Service directive in the obj.conf file that define information about the SSL connection. For the list of parameters, see SSL Parameters for Web Server Plug-Ins.\n\n6.3 Configuring Perimeter Authentication\n\nUse perimeter authentication to secure WebLogic Server applications that are accessed by using the plug-in.\n\nA WebLogic Identity Assertion Provider authenticates tokens from outside systems that access your WebLogic Server application, including users who access your WebLogic Server application through the plug-in. Create an Identity Assertion Provider that will safely secure your plug-in as follows:\n\n1. Create a custom Identity Assertion Provider on your WebLogic Server application. See \"How to Develop a Custom Identity Assertion Provider\" in .\n\n2. Configure the custom Identity Assertion Provider to support the Cert token type and make Cert the active token type. See \"How to Create New Token Types\" in .\n\n3. Set clientCertProxy to True in the web.xml deployment descriptor file for the Web application (or, if using a cluster, optionally set the Client Cert Proxy Enabled attribute to true for the whole cluster on the Administration Console Cluster then Configuration then General tab).\n\nThe clientCertProxy attribute can be used with a third party proxy server, such as a load balancer or an SSL accelerator, to enable 2-way SSL authentication. For more information about the clientCertProxy attribute, see context-param in Developing Web Applications, Servlets, and JSPs for Oracle WebLogic Server.\n4. Once you have set `clientCertProxy`, be sure to use a connection filter to ensure that WebLogic Server accepts connections only from the machine on which the plug-in is running. See \"Using Network Connection Filters\" in.\n\n5. Web server plug-ins require a trusted Certificate Authority file to use SSL between the plug-in and WebLogic Server. See Using SSL with Plug-Ins for the steps you need to perform to configure SSL.\n\nSee \"Identity Assertion Providers\" in.\nThis chapter describes tasks that are common across all the web servers for configuring the plug-ins provided by Oracle. It contains the following sections:\n\n- Configuring IPv6 With Plug-Ins\n- Understanding Connection Errors and Clustering Failover\n- Tuning Oracle HTTP Server and Apache HTTP Server for High Throughput for WebSocket Upgrade Requests\n- Working with Partitions\n\n### 7.1 Configuring IPv6 With Plug-Ins\n\nThe version 12c (12.2.1.1.0) plug-ins support IPv6. Specifically, the `WebLogicHost` and `WebLogicCluster` configuration parameters (see `WebLogicCluster` and `WebLogicHost`) now support IPv6 addresses. For example:\n\n```html\n<IfModule mod_weblogic.c>\n WebLogicHost [a:b:c:d:e:f]\n WebLogicPort 7002\n ...\n</IfModule>\n```\n\nor\n\n```html\n<IfModule mod_weblogic.c>\n WebLogicCluster [a:b:c:d:e:f]:<port>, [g:h:i:j:k:l]:<port>\n ....\n</IfModule>\n```\n\nYou can also use the IPv6 address mapped host name.\nNote:\nAs of Windows 2008, the DNS server returns the IPv6 address in preference to\nthe IPv4 address. If you are connecting to a Windows 2008 (or later) system\nusing IPv4, the link-local IPv6 address format is tried first, which may result\nin a noticeable delay and reduced performance. To use the IPv4 address\nformat, configure your system to instead use IP addresses in the configuration\nfiles or add the IPv4 addresses to the etc/hosts file.\n\nIn addition, you may find that setting the DynamicServerList property to\nOFF in the mod_wl_ohs.conf/mod_wl.conf/iisproxy.ini file also\nimproves performance with IPv6. When set to OFF, the plug-in ignores\nthe dynamic cluster list used for load balancing requests proxied from the plug-in\nand uses the static list specified with the WebLogicCluster parameter.\n\n7.2 Understanding Connection Errors and Clustering Failover\n\nWhen the plug-in attempts to connect to WebLogic Server, the plug-in uses several\nconfiguration parameters to determine how long to wait for connections to the\nWebLogic Server host and, after a connection is established, how long the plug-in\nwaits for a response. If the plug-in cannot connect or does not receive a response, the\nplug-in attempts to connect and send the request to other WebLogic Server instances\nin the cluster. If the connection fails or there is no response from any WebLogic Server\nin the cluster, an error message is sent.\n\nFigure 7-1 illustrates how the plug-in handles failover.\n\nThis section contains the following information:\n\n• Possible Causes of Connection Failures\n• Tips for Reducing CONNECTION_REFUSED Errors\n• Failover with a Single, Non-Clustered WebLogic Server\n• The Dynamic Server List\n• Failover, Cookies, and HTTP Sessions\n• Failover Behavior When Using Firewalls and Load Directors\n\n7.2.1 Possible Causes of Connection Failures\n\nFailure of the WebLogic Server host to respond to a connection request could indicate\nthe following problems:\n\n• Physical problems with the host machine\n• Network problems\n• Other server failures\n\nFailure of all WebLogic Server instances to respond could indicate the following\nproblems:\n\n• WebLogic Server is not running or is unavailable\n• A hung server\n• A database problem\n• An application-specific failure\n\n7.2.2 Tips for Reducing CONNECTION_REFUSED Errors\n\nUnder load, a plug-in may receive CONNECTION_REFUSED errors from a back-end WebLogic Server instance. Follow these tuning tips to reduce CONNECTION_REFUSED errors:\n\n• Increase the AcceptBackLog setting in the configuration of your WebLogic Server domain.\n\n• Decrease the time wait interval. This setting varies according to the operating system you are using. For example:\n \n – On Windows NT, set the TcpTimedWaitDelay on the proxy and WebLogic Server servers to a lower value. Set the TIME_WAIT interval in Windows NT by editing the registry key under HKEY_LOCAL_MACHINE:\n \n SYSTEM\\CurrentControlSet\\Services\\Tcpip\\Parameters\\TcpTimedWaitDelay\n \n If this key does not exist you can create it as a DWORD value. The numeric value is the number of seconds to wait and may be set to any value between 30 and 240. If not set, Windows NT defaults to 240 seconds for TIME_WAIT.\n\n – On Windows 2000, lower the value of the TcpTimedWaitDelay by editing the registry key under HKEY_LOCAL_MACHINE:\n \n SYSTEM\\CurrentControlSet\\Services\\Tcpip\\Parameters\n \n – On Solaris, reduce the setting tcp_time_wait_interval to one second (for both the WebLogic Server machine and the Apache machine, if possible):\n \n $ndd /dev/tcp\n param name to set - tcp_time_wait_interval\n value=1000\n\n• Increase the open file descriptor limit on your machine. This limit varies by operating system. Using the limit (.csh) or ulimit (.sh) directives, you can make a script to increase the limit. For example:\n \n #!/bin/sh\n ulimit -S -n 100\n exec httpd\n\n• On Solaris, increase the values of the following tunables on the WebLogic Server machine:\n \n tcp_conn_req_max_q tcp_conn_req_max_q0\n\n7.2.3 Failover with a Single, Non-Clustered WebLogic Server\n\nIf you run only a single WebLogic Server instance the plug-in only attempts to connect to the server defined with the WebLogicHost parameter. If the attempt fails, an HTTP 503 error message is returned. The plug-in continues trying to connect to that same WebLogic Server instance for the maximum number of retries as specified by the ratio of ConnectTimeoutSecs and ConnectRetrySecs.\n7.2.4 The Dynamic Server List\n\nThe WebLogicCluster parameter is required to proxy to a list of back-end servers that are clustered, or to perform load balancing among non-clustered managed server instances.\n\nIn the case of proxying to clustered managed servers, when you use the WebLogicCluster parameter to specify a list of WebLogic Servers, the plug-in uses that list as a starting point for load balancing among the members of the cluster. After the first request is routed to one of these servers, a dynamic server list is returned containing an updated list of servers in the cluster.\n\nThe updated list adds any new servers in the cluster and deletes any that have been shut down, or are being suspended, or are no longer part of the cluster or that have failed to respond to requests. This feature can be controlled by using DynamicServerList. For example, to disable this feature, set DynamicServerList to OFF.\n\nDynamicServerList ON is a preferred performance tuning parameter. It is useful, for example, if a member of a cluster is temporarily down for maintenance or if administrators decide they want to add another member, and not need to restart the web server.\n\n**Note:**\n\nIf DynamicServerList is set to ON, and the list of backend WebLogic Servers specified in WebLogicCluster is not in a cluster, then the behavior would be undefined.\n\n7.2.5 Failover, Cookies, and HTTP Sessions\n\nWhen a request contains session information stored in a cookie or in the POST data, or encoded in a URL, the session ID contains a reference to the specific server instance in which the session was originally established (called the primary server). A request containing a cookie attempts to connect to the primary server. If that attempt fails, the plug-in attempts to make a connection to the next available server in the list in a round-robin fashion. That server retrieves the session from the original secondary server and makes itself the new primary server for that same session. See Figure 7-1.\n\n**Note:**\n\nIf the POST data is larger than 64K, the plug-in will not parse the POST data to obtain the session ID. Therefore, if you store the session ID in the POST data, the plug-in cannot route the request to the correct primary or secondary server, resulting in possible loss of session data.\nFigure 7-1 Connection Failover\n\nClient Sends HTTP request to Web server and the request is proxied by the plug-in\n\nPlug-In receives request from the Web server\n\nWebLogic session ID in request?\n\nYes\n\nConnection successful within WLSocketTimeOutsecs?\n\nYes\n\nTry next server in dynamic server list or WebLogicCluster\n\nNo\n\nSend HTTP error code 5xx to client\n\nNo\n\nSleep for ConnectionRetrySeconds\n\nMax retries exceeded?\n\nYes\n\nNo\n\nWait for response for WLIOTimeOutSecs\n\nSend headers and POST data to WebLogic server\n\nNo\n\nYes\n\nTotal time of this request exceeded ConnectionTimeOutSecs?\n\nYes\n\nNo\n\nIs this the first failover?\n\nYes\n\nNo\nIn this figure, the Maximum number of retries allowed in the red loop is equal to ConnectTimeoutSecs/ConnectRetrySecs.\n\n7.2.6 Failover Behavior When Using Firewalls and Load Directors\n\nIn most configurations, the Oracle WebLogic Server Proxy Plug-In 12c (12.2.1.1.0) for iPlanet Web Server sends a request to the primary instance of a cluster. When that instance is unavailable, the request fails over to the secondary instance. However, in some configurations that use combinations of firewalls and load-directors, any one of the servers (firewall or load-directors) can accept the request and return a successful connection while the primary instance of WebLogic Server is unavailable. After attempting to direct the request to the primary instance of WebLogic Server (which is unavailable), the request is returned to the plug-in as \"connection reset.\"\n\nRequests running through combinations of firewalls (with or without load-directors) are handled by WebLogic Server. In other words, responses of connection reset fail over to a secondary instance of WebLogic Server. Because responses of connection reset fail over in these configurations, servlets must be idempotent. Otherwise duplicate processing of transactions may result.\n\n7.3 Tuning Oracle HTTP Server and Apache HTTP Server for High Throughput for WebSocket Upgrade Requests\n\nWebLogic Server 12c (12.2.1.1.0) supports deploying WebSocket applications. Oracle WebLogic Server Proxy Plug-In 12c (12.2.1.1.0) for Oracle HTTP Server 12c (12.2.1.1.0) and Apache HTTP Server 2.2.x and 2.4.x can now handle such WebSocket connection upgrade requests and effectively proxy to WebSocket applications hosted within WebLogic Server 12c (12.2.1.1.0) and later. As a result of adding this support, a new configuration parameter WLMaxWebSocketClients is introduced.\n\nThe WLMaxWebSocketClients parameter limits the number of active WebSocket connections at any instant of time. The maximum value you can set for this parameter is 75 percent of ThreadsPerChild (Windows) or 75 percent of MaxRequestWorkers (non-Windows). Hence, to tune your HTTP Server for maximum WebSocket connection upgrade requests, set MaxRequestWorkers/ThreadsPerChild to a value that can accommodate WebSocket connections as well. Also, ensure that WLMaxWebSocketClients is set to 75 percent of MaxRequestWorkers/ThreadsPerChild.\n\n7.4 Working with Partitions\n\nBy doing some manual configuration, Oracle WebLogic Server Proxy Plug-Ins can front-end Oracle WebLogic Server MT (Multi-Tenency).\n\nThis section contains the following information:\n\n---\n\n**Note:**\n\nThis section describes partitions and multi-tenancy only as far as they apply to Oracle WebLogic Server Proxy Plug-Ins. For more information about Oracle WebLogic Server MT, partitions, and multi-tenancy, see Oracle Fusion Middleware Using WebLogic Server MT.\n\n---\n\n- Adding a Partition\n7.4.1 Adding a Partition\n\nWhenever a partition is added on the Oracle WebLogic Server MT side, you must make corresponding changes to the web server configuration to front the new partition. The details of adding a partition itself is documented by Oracle WebLogic Server MT, (see “Configuring Domain Partitions” in Oracle Fusion Middleware Using WebLogic Server MT).\n\nThe following sections describe how to make corresponding changes to web server configuration to front-end a newly added partition in Oracle WebLogic Server MT.\n\nNote:\n\nThese sections assume that you have already created one or more domain partitions in Oracle WebLogic Server. For more information on creating domain partitions, see “Configuring Domain Partitions” in Oracle Fusion Middleware Using WebLogic Server MT.\n\n7.4.1.1 Apache Server and Oracle HTTP Server Configuration Changes\n\nThe following is a sample configuration that must be added to the Oracle HTTP Server or Apache plug-in configuration file (httpd.conf) for each new partition being added. The configuration identifies the hostname and port of the partition, the server and the WebLogic cluster it belongs to, and any optional URI that is configured for the partition.\n\n1. Install and configure the plug-in for Oracle HTTP Server or Apache Server. See Preparing for Configuring the Oracle WebLogic Server Proxy Plug-In or Install the Oracle WebLogic Server Proxy Plug-In for Apache HTTP Server.\n\n2. Edit the httpd.conf file and add the following section for every new partition:\n\n```bash\n# For OHS: Uncomment the following line\n# LoadModule weblogic_module modules/mod_wl_ohs.so\n# For Apache 2.2: Uncomment the following line\n# LoadModule weblogic_module modules/mod_wl.so\n# For Apache 2.4: Uncomment the following line\nLoadModule weblogic_module modules/mod_wl_24.so\n\n<VirtualHost hostname_and_port_of_the_partition>\n <IfModule mod_weblogic.c>\n ServerName server_URL\n WebLogicCluster comma_separated_list_of_WebLogic_clusters\n SetHandler weblogic-handler\n PathPrepend optional_uri_of_the_partition\n </IfModule>\n</VirtualHost>\n```\n\n- Apache Server and Oracle HTTP Server Configuration Changes\n- iPlanet Server Configuration Changes\n- IIS Server Configuration Changes\n3. After making the configuration change, you must restart the Apache or Oracle HTTP Server.\n\n7.4.1.1 Oracle HTTP Server/Apache Plug-in Examples\n\nThe following examples provide sample configurations for different use cases.\n\nExample 1: Client may not configure the partition path\n\nAssume there are two partitions in the domain:\n\n- Host Name of the VirtualTarget1 is www.myCompany1.com and the URI Prefix (partition path) is null as configured in Oracle WebLogic Server.\n\n- Host Name of the VirtualTarget2 is www.myCompany2.com and the URI Prefix (partition path) is null as configured in Oracle WebLogic Server.\n\nIn this case, you do not need to configure the partition path:\n\n```xml\nLoadModule weblogic_module modules/mod_wl_24.so\n<VirtualHost *:8080>\n <IfModule mod_weblogic.c>\n ServerName www.myCompany1.com\n WebLogicCluster wls1:7001,wls2:7001,wls3:7001\n SetHandler weblogic-handler\n </IfModule>\n</VirtualHost>\n\n<VirtualHost *:8080>\n <IfModule mod_weblogic.c>\n ServerName www.myCompany2.com\n WebLogicCluster wls1:7002,wls2:7002,wls3:7002\n SetHandler weblogic-handler\n </IfModule>\n</VirtualHost>\n```\n\nThis configuration proxies all of the requests coming to myCompany1.com:8080 or myCompany1.com to the managed servers wls1:7001, wls2:7001, and wls3:7001. Similarly, all of the requests coming to myCompany2.com:8080 or myCompany2.com will be proxied to the managed servers wls1:7002, wls2:7002, and wls3:7002.\n\nExample 2: Client may divide the web site by the partition path\n\nAssume there are two partitions in the domain:\n\n- Host Name of the VirtualTarget1 is www.foo.com and URI Prefix (partition path) is /myCompany1 as configured in Oracle WebLogic Server.\n\n- Host Name of the VirtualTarget2 is www.foo.com and URI Prefix (partition path) is /myCompany2 as configured in Oracle WebLogic Server.\n\nIn this case, you do not need to configure the partition path:\n\n```xml\n<VirtualHost *:8080>\n <IfModule mod_weblogic.c>\n ServerName server1\n WebLogicCluster wls1:7001,wls2:7001,wls3:7001\n SetHandler weblogic-handler\n </IfModule>\n</VirtualHost>\n```\nThe available urls will be:\nwww.foo.com:8080/myCompany1\nwww.foo.com:8080/myCompany2\n\n7.4.1.2 iPlanet Server Configuration Changes\n\nThe following is a sample configuration that must be added to the iPlanet Server plug-in configuration file for each new partition being added.\n\n1. Install the plug-in for iPlanet Server. See Installing and Configuring the Plug-In for iPlanet.\n\n2. Edit the magnus.conf file to add the following section:\n\n ServerName server_URL\n Init fn=\"load-modules\" shlib=\"path to the /plugin/mod_wl.so file\"\n\n For example:\n ServerName www.myCompany.com\n Init fn=\"load-modules\" shlib=\"/scratch/plugin/mod_wl.so\"/\n\n3. Edit the obj.conf file to add the following section for every new partition:\n\n <Object name=\"weblogic\" ppath=\"*\">\n Service ChunkedRequestBufferSize=\"0\" fn=\"wl-proxy\"\n WebLogicCluster=\"comma_separated_list_of_WebLogic_clusters\"\n PathPrepend=\"optional_uri_of_the_partition\" SecureProxy=\"OFF\"\n WLIOTimeoutSecs=\"10\"\n </Object>\n\n For example:\n <Object name=\"weblogic\" ppath=\"*\">\n Service ChunkedRequestBufferSize=\"0\" fn=\"wl-proxy\"\n WebLogicCluster=\"wls1:7001,wls2:7001,wls3:7001\" PathPrepend=\"/partition1\"\n SecureProxy=\"OFF\" WLIOTimeoutSecs=\"10\"\n </Object>\n\n4. After making the configuration change, you must restart the iPlanet Server.\n\n7.4.1.3 IIS Server Configuration Changes\n\nThe following is a sample configuration that must be added to the Microsoft IIS plug-in configuration file for each new partition being added.\n\n1. Install the plug-in for Microsoft IIS Server. See Installing and Configuring the Microsoft IIS 7.5 Plug-In.\n\n2. Open IIS Manager and create a new Web Site.\n Set Host name. For example, set it to www.myCompany.com.\n\n3. Add the plug-in to the IIS server.\n Click Handler Mappings in IIS Manager to set the mappings to the handler for a particular MIME type.\n4. Create a plug-in configuration file:\n\nCreate a file named `iisproxy.ini` with the following content and place it in the directory with the plug-in. Create similar content in the file for every new partition:\n\n```ini\nWebLogicCluster=comma_separated_list_of_WebLogic_clusters\nDebug=ALL\nWLLogFile=path to the wlproxy.log file\nPathPrepend=optional_uri_of_the_partition\nSecureProxy=OFF\nWLIOTimeoutSecs=10\n```\n\nFor example:\n\n```ini\nWebLogicCluster=wls1:7001,wls2:7001,wls3:7001\nDebug=ALL\nWLLogFile=C:/pp_iis_home/myCompany/logs/iis7.0_wlproxy.log\nPathPrepend=/partition1\nSecureProxy=OFF\nWLIOTimeoutSecs=10\n```\n\n5. After making the configuration change, you must restart the Microsoft IIS Server.\n\n### 7.4.2 Modifying a Partition and Partition Migration\n\nPartition migration is an Oracle WebLogic Server MT feature. You cannot migrate partitions on the Oracle WebLogic Server Proxy Plug-In side. Once the partition is migrated, the Oracle WebLogic Server Proxy Plug-In configuration must be updated manually to use the new partition information.\n\nFor more information on partition migration, see “Exporting and Importing Partitions” in *Oracle Fusion Middleware Using WebLogic Server MT*.\n\nIf you make any changes in the partition on the Oracle WebLogic Server side, you must make corresponding changes in the plug-in configuration. On the Oracle WebLogic Server side you can typically change the VirtualHost parameters (host and port) and the optional URI. In this case, you must edit the ServerName and PathPrepend parameters in the plug-in configuration.\n\nIf you add, delete, or migrate managed servers on the Oracle WebLogic Server side, you must also make corresponding changes in the plug-in configuration.\n\nFor example, assume you have the following Oracle HTTP Server (or Apache) plug-in configuration:\n\n```xml\n<VirtualHost *:8080>\n <IfModule mod_weblogic.c>\n ServerName server1\n WebLogicCluster wls1:7001,wls2:7001,wls3:7001\n SetHandler weblogic-handler\n </IfModule>\n</VirtualHost>\n```\n\nIf you add managed server `wls4` to the partition, then add `wls4` to the `WebLogicCluster` parameter:\n\n```xml\n<VirtualHost *:8080>\n <IfModule mod_weblogic.c>\n ServerName server1\n WebLogicCluster wls1:7001,wls2:7001,wls3:7001, wls4:7001\n SetHandler weblogic-handler\n </IfModule>\n</VirtualHost>\n```\nIf you delete managed server wls1 from the partition, then delete wls1 from the WebLogicCluster parameter:\n\n```xml\n<VirtualHost *:8080>\n <IfModule mod_weblogic.c>\n ServerName server1\n WebLogicCluster wls2:7001,wls3:7001,wls4:7001\n SetHandler weblogic-handler\n </IfModule>\n</VirtualHost>\n```\n\nIf you migrate managed server wls2 to wls5 then remove wls2 and add wls5 to the WebLogicCluster parameter:\n\n```xml\n<VirtualHost *:8080>\n <IfModule mod_weblogic.c>\n ServerName server1\n WebLogicCluster wls3:7001,wls4:7001,wls5:7001\n SetHandler weblogic-handler\n </IfModule>\n</VirtualHost>\n```\n\nFor information on modifying a partition of the Oracle WebLogic Server side, see \"Configuring Domain Partitions,\" \"Configuring Virtual Targets,\" and \"Exporting and Importing Partitions,\" in Oracle Fusion Middleware Using WebLogic Server MT.\n\n### 7.4.3 Configuring SSL Between the Web Server and Oracle WebLogic Server\n\nYou configure SSL on Oracle WebLogic Server MT in the same way as with Oracle WebLogic Server, however, the partitions that are targeted to the same host name should have same certificate.\n\n### 7.4.4 Dynamic Discovery of Cluster Changes\n\nThe dynamic discovery of cluster changes is a feature of both Oracle WebLogic Server Proxy Plug-In and Oracle WebLogic Server. It is not affected by Multitenancy. This feature can be controlled by the `DynamicServerList` parameter. For more information, see `DynamicServerList`. \n\n---\n\n**Working with Partitions**\n\n**Common Configuration Tasks** 7-11\nThis chapter describes the parameters that you can use to configure the Oracle HTTP Server, Apache HTTP Server, Microsoft IIS, and Oracle iPlanet Web Server plug-ins. It contains the following sections:\n\n- General Parameters for Web Server Plug-Ins\n- SSL Parameters for Web Server Plug-Ins\n- Location of POST Data Files\n\nNote:\nThe parameters for the web-server plug-ins should be specified in special configuration files, which are named and formatted uniquely for each web server. For information about the configuration files specific to the plug-ins for Apache HTTP Server, Oracle HTTP Server, Microsoft IIS, and Oracle iPlanet Web Server, see the following chapters:\n\n- Configuring the Plug-In for Oracle HTTP Server\n- Configuring the Plug-In for Apache HTTP Server\n- Configuring the Plug-In for iPlanet Web Server\n- Configuring the Plug-In for Microsoft IIS Web Server\n\n8.1 General Parameters for Web Server Plug-Ins\n\nThe general parameters for Web server plug-ins are described in the following sections. The parameter names are case sensitive.\n\n- ConnectRetrySecs\n- ConnectTimeoutSecs\n- Debug\n- DebugConfigInfo\n- DefaultFileName\n- DynamicServerList\n- ErrorPage\n- FileCaching\n- Idempotent\n- KeepAliveEnabled\n- KeepAliveSecs\n- MatchExpression\n- MaxPostSize\n- MaxSkipTime\n- PathPrepend\n- PathTrim\n- QueryFromRequest\n- WebLogicCluster\n- WebLogicHost\n- WebLogicPort\n- WLCookieName\n- WLDNSRefreshInterval\n- WLExcludePathOrMimeType\n- WLFflushChunks\n- WLForwardUriUnparsed\n- WLIOTimeoutSecs\n- WLLocalIP\n- WLLogFile\n- WLMaxWebSocketClients\n- WLProxyPassThrough\n- WLProxySSL\n- WLProxySSLPassThrough\n- WLRetryAfterDroppedConnection\n- WLSendHdrSeparately\n- WLServerInitiatedFailover\n- WLSocketTimeoutSecs\n- WLSRequest\n- WLTempDir\n8.1.1 ConnectRetrySecs\n\n**Default:** 2\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nInterval in seconds that the plug-in should sleep between attempts to connect to the WebLogic Server host (or all of the servers in a cluster). Make this number less than the ConnectTimeoutSecs. The number of times the plug-in tries to connect before returning an HTTP 503/Service Unavailable response to the client is calculated by dividing ConnectTimeoutSecs by ConnectRetrySecs.\n\nTo specify no retries, set ConnectRetrySecs equal to ConnectTimeoutSecs. However, the plug-in attempts to connect at least twice.\n\nYou can customize the error response by using the ErrorPage parameter.\n\n8.1.2 ConnectTimeoutSecs\n\n**Default:** 10\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nMaximum time in seconds that the plug-in should attempt to connect to the WebLogic Server host. Make the value greater than ConnectRetrySecs. If ConnectTimeoutSecs expires without a successful connection, even after the appropriate retries (see ConnectRetrySecs), an HTTP 503/Service Unavailable response is sent to the client.\n\nYou can customize the error response by using the ErrorPage parameter.\n\n8.1.3 Debug\n\n**Default:** OFF\n\n**Applies to:** Microsoft IIS\n\nSets the type of logging performed for debugging operations. The debugging information is written to c:\\TEMP\\wlproxy.log on Windows NT/2000 systems.\n\nOverride this location and filename by setting the WLLogFile parameter to a different directory and file. (See the WLTempDir parameter for an additional way to change this location.)\n\nEnsure that the directory of the log file has write permission. Set any of the following logging options (HFC,HTW,HFW, and HTC options may be set in combination by entering them separated by commas, for example \"HFC,HTW\"):\n\n- **ON:** The plug-in logs informational and error messages.\n- **OFF:** No debugging information is logged.\n- **HFC:** The plug-in logs headers from the client, informational, and error messages.\n- **HTW:** The plug-in logs headers sent to WebLogic Server, and informational and error messages.\n- **HFW:** The plug-in logs headers sent from WebLogic Server, and informational and error messages.\n• HTC: The plug-in logs headers sent to the client, informational messages, and error messages.\n\n• ERR: Prints only the Error messages in the plug-in.\n\n• ALL: The plug-in logs headers sent to and from the client, headers sent to and from WebLogic Server, information messages, and error messages.\n\nFor information on setting logging without using the deprecated parameter, see Deprecated Directives for Apache HTTP Server.\n\n8.1.4 DebugConfigInfo\n\nDefault: OFF\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nEnables the special query parameter \"__WebLogicBridgeConfig\". Use it to get details about configuration parameters from the plug-in.\n\nFor example, if you enable \"__WebLogicBridgeConfig\" by setting DebugConfigInfo and then send a request that includes the query string ?__WebLogicBridgeConfig, then the plug-in gathers the configuration information and run-time statistics and returns the information to the browser. The plug-in does not connect to WebLogic Server in this case.\n\nThis parameter is strictly for debugging and the format of the output message can change with releases. For security purposes, keep this parameter turned OFF in production systems.\n\n8.1.5 DefaultFileName\n\nDefault: none\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nIf the URI is \"/\" then the plug-in performs the following steps:\n\n1. Trims the path specified with the PathTrim parameter.\n\n2. Appends the value of DefaultFileName.\n\n3. Prepends the value specified with PathPrepend.\n\nThis procedure prevents redirects from WebLogic Server.\n\nSet the DefaultFileName to the default welcome page of the Web Application in WebLogic Server to which requests are being proxied. For example, If the DefaultFileName is set to welcome.html, an HTTP request like \"http://somehost/weblogic\" becomes \"http://somehost/weblogic/welcome.html\". For this parameter to function, the same file must be specified as a welcome file in all the Web Applications to which requests are directed. For more information, see Configuring Welcome Pages.\n\nNote for Apache users: If you are using Stronghold or Raven versions, define this parameter inside of a Location block, and not in an IfModule block.\n\n8.1.6 DynamicServerList\n\nDefault: ON\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nWhen set to OFF, the plug-in ignores the dynamic cluster list used for load balancing requests proxied from the plug-in and only uses the static list specified with the WebLogicCluster parameter. Normally this parameter should remain set to ON.\n\nThere are some implications for setting this parameter to OFF:\n\n- If one or more servers in the static list fails, the plug-in could waste time trying to connect to a terminated server, resulting in decreased performance.\n- If you add a new server to the cluster, the plug-in cannot proxy requests to the new server unless you redefine this parameter. WebLogic Server automatically adds new servers to the dynamic server list when they become part of the cluster.\n\n8.1.7 ErrorPage\n\nDefault: none\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nYou can create your own error page that is displayed when your Web server cannot forward requests to WebLogic Server.\n\nThe plug-in redirects to an error page when the back-end server returns an HTTP 503/Service Unavailable response and there are no servers for failover.\n\n8.1.8 FileCaching\n\nDefault: ON\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nWhen set to ON, and the size of the POST data in a request is greater than 2048 bytes, the POST data is first read into a temporary file on disk and then forwarded to the WebLogic Server in chunks of 8192 bytes. This preserves the POST data during failover, allowing all necessary data to be repeated to the secondary if the primary goes down.\n\nWhen FileCaching is ON, any client that tracks the progress of the POST will see that the transfer has completed even though the data is still being transferred between the WebServer and WebLogic. So, if you want the progress bar displayed by a browser during the upload to reflect when the data is actually available on the WebLogic Server, you might not want to have FileCaching ON.\n\nWhen set to OFF and the size of the POST data in a request is greater than 2048 bytes, the reading of the POST data is postponed until a WebLogic Server cluster member is identified to serve the request. Then the plug-in reads and immediately sends the POST data to the WebLogic Server in chunks of 8192 bytes.\n\nTurning FileCaching OFF limits failover. If the WebLogic Server primary server goes down while processing the request, the POST data already sent to the primary cannot be repeated to the secondary.\n\nFinally, regardless of how FileCaching is set, if the size of the POST data is 2048 bytes or less the plug-in will read the data into memory and use it if needed during failover to repeat to the secondary.\n8.1.9 Idempotent\n\n**Default:** ON\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nWhen set to ON and if the servers do not respond within WLIOTimeoutSecs, the plug-ins fail over if the method is idempotent.\n\nThe plug-ins also fail over if Idempotent is set to ON and the servers respond with an error such as READ_ERROR_FROM_SERVER.\n\nIf set to \"OFF\" the plug-ins do not fail over. If you are using the Apache HTTP Server you can set this parameter differently for different URLs or MIME types.\n\nIdempotent only takes effect if the request has been successfully sent to WebLogic Server and the plugin is now waiting for a response from backend server.\n\n8.1.10 KeepAliveEnabled\n\n**Default:** true (Microsoft IIS plug-in), ON (Oracle HTTP Server and Apache HTTP Server), ON (Oracle iPlanet Web Server)\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nEnables pooling of connections between the plug-in and WebLogic Server.\n\n- Valid values for the Microsoft IIS plug-ins are true and false.\n- Valid values for the Apache HTTP Server are ON and OFF.\n \n While using Apache prefork mpm, Apache web server might fail. Set KeepAliveEnabled to OFF when using prefork mpm or use worker mpm in Apache.\n\n- Valid values for Oracle iPlanet Webserver are ON and OFF\n\n8.1.11 KeepAliveSecs\n\n**Default:** 20\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nThe length of time after which an inactive connection between the plug-in and WebLogic Server is closed. You must set KeepAliveEnabled to true (ON when using the Apache HTTP Server) for this parameter to be effective.\n\nThe value of this parameter must be less than or equal to the value of the Duration field set in the Administration Console on the Server/HTTP tab, or the value set on the server Mbean with the KeepAliveSecs attribute.\n\n8.1.12 MatchExpression\n\n**Default:** none\n\n**Applies to:** Oracle HTTP Server, Apache HTTP Server\n\nUse this parameter to modify the values of existing parameters or add a new parameter for a particular configuration.\nThe MatchExpression parameter supports only the * and ? regular expressions\n\n- * which matches 0 or more characters\n- ? which matches exactly one character\n\nThis parameter can be configured for two scenarios.\n\n**Proxying by MIME type:**\n\nYou can use this parameter in the following format to set other parameters for a particular MIME type.\n\n**Syntax:**\n\n```\nMatchExpression <file_extension> <param>=value|<param>=value|...\n```\n\nFor example, the following configuration proxies *.jsp to myHost:8080:\n\n```\n<IfModule weblogic_module>\nMatchExpression *.jsp WebLogicHost=myHost|WebLogicPort=8080\n</IfModule>\n```\n\n**Proxying by path:**\n\nYou can also use this parameter in the following format to set other parameters for a particular path.\n\n**Syntax:**\n\n```\nMatchExpression <path> <param>=value|<param>=value|...\n```\n\nFor example, the following configuration proxies the URIs beginning with /weblogic to myHost:9090:\n\n```\n<IfModule weblogic_module>\nMatchExpression /weblogic WebLogicHost=myHost|WebLogicPort=9090\n</IfModule>\n```\n\nYou can also use MatchExpression to override the parameter values, as shown above. It can also be used to define new parameters (this is, those that have not been used in the configuration).\n\nFor example, the configuration below proxies all the requests to myHost:8080. The URIs that match the type jpg will be proxied to myHost:8080/images and others will be proxied to myHost:8080.\n\n```\n<IfModule weblogic_module>\nSetHandler weblogic-handler\nWebLogicHost myHost\nWebLogicPort 8080\nMatchExpression *.jpg PathPrepend=/images\n</IfModule>\n```\n\nYou can find more examples of how to use MatchExpression in Configuring the Plug-In for Apache HTTP Server.\n\n### 8.1.13 MaxPostSize\n\n**Default:** 0\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\nMaximum allowable size of POST data, in bytes. If the content-length exceeds MaxPostSize, the plug-in returns an error message. If set to 0, the size of POST data is not checked. This is useful for preventing denial-of-service attacks that attempt to overload the server with POST data.\n\n8.1.14 MaxSkipTime\n\nDefault: 10\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nIf a WebLogic Server listed in either the WebLogicCluster parameter or a dynamic cluster list returned from WebLogic Server fails, the failed server is marked as \"bad\" and the plug-in attempts to connect to the next server in the list.\n\nMaxSkipTime sets the amount of time after which the plug-in will retry the server marked as \"bad.\" The plug-in attempts to connect to a new server in the list each time a unique request is received (that is, a request without a cookie).\n\n8.1.15 PathPrepend\n\nDefault: null\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nAs per the RFC specification, generic syntax for URL is:\n\n```\n[PROTOCOL]://[HOSTNAME]:{PORT}/{PATH}/{FILENAME};{PATH_PARAMS}/{QUERY_STRING}...\n```\n\nPathPrepend specifies the path that the plug-in prepends to the \\{PATH\\} portion of the original URL, after PathTrim is trimmed and before the request is forwarded to WebLogic Server.\n\nIf you must append a File Name, use DefaultFileName parameter instead of PathPrepend.\n\n8.1.16 PathTrim\n\nDefault: null\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nAs per the RFC specification, generic syntax for URL is:\n\n```\n[PROTOCOL]://[HOSTNAME]:{PORT}/{PATH}/{FILENAME};{PATH_PARAMS}/{QUERY_STRING}...\n```\n\nPathTrim specifies the string trimmed by the plug-in from the \\{PATH\\}/{FILENAME} portion of the original URL, before the request is forwarded to WebLogic Server. For example, if this URL:\n\n```\nhttp://myWeb.server.com/weblogic/foo\n```\n\nis passed to the plug-in for parsing and if PathTrim has been set to strip off /weblogic before handing the URL to WebLogic Server, the URL forwarded to WebLogic Server is:\n\n```\nhttp://myWeb.server.com:7001/foo\n```\n\nIf you are newly converting an existing third-party server to proxy requests to WebLogic Server using the plug-in, you will need to change application paths to /foo\nto include weblogic/foo. You can use PathTrim and PathPrepend in combination to change this path.\n\n8.1.17 QueryFromRequest\n\n**Default:** OFF\n\n**Applies to:** Oracle HTTP Server, Apache HTTP Server\n\nWhen set to ON, specifies that the Apache HTTP Server use\n\n\\[(\\text{request_rec } \\ast)\\rightarrow \\text{the_request}\\]\n\n...to pass the query string to WebLogic Server. (For more information, see the Apache documentation.) This behavior is desirable when a Netscape version 4.x browser makes requests that contain spaces in the query string.\n\nWhen set to OFF, the Apache HTTP Server uses \\[(\\text{request_rec } \\ast)\\rightarrow \\text{args}\\] to pass the query string to WebLogic Server.\n\n8.1.18 WebLogicCluster\n\nRequired when proxying to a cluster of WebLogic Servers, or to multiple non-clustered servers.\n\n**Default:** none\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nThe `WebLogicCluster` parameter is required to proxy a list of back-end servers that are clustered, or to perform load balancing among non-clustered managed server instances.\n\nList of WebLogic Servers that can be used for load balancing. The server or cluster list is a list of `host:port` entries. If a mixed set of clusters and single servers is specified, the dynamic list returned for this parameter will return only the clustered servers.\n\nThe syntax for specifying the value of this parameter varies depending on the web server for which you are configuring the plug-in. For more information, see the following:\n\n- Configuring the Plug-In for Oracle HTTP Server\n- Configuring the Plug-In for Apache HTTP Server\n- Configuring the Plug-In for iPlanet Web Server\n- Configuring the Plug-In for Microsoft IIS Web Server\n\nIf you are using SSL between the plug-in and WebLogic Server, set the port number to the SSL listen port and set the SecureProxy parameter to ON.\n\nThe plug-in does a simple round-robin between all available servers. The server list specified in this property is a starting point for the dynamic server list that the server and plug-in maintain. WebLogic Server and the plug-in work together to update the server list automatically with new, failed, and recovered cluster members.\n\nYou can disable the use of the dynamic cluster list by setting the DynamicServerList parameter to OFF.\n\nThe plug-in directs HTTP requests containing a cookie, URL-encoded session, or a session stored in the POST data to the server in the cluster that created the cookie.\n8.1.19 WebLogicHost\n\nRequired when proxying to a single WebLogic Server.\n\n**Default:** none\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nWebLogic Server host (or virtual host name as defined in WebLogic Server) to which HTTP requests should be forwarded. If you are using a WebLogic cluster, use the WebLogicCluster parameter instead of WebLogicHost.\n\n8.1.20 WebLogicPort\n\nRequired when proxying to a single WebLogic Server.\n\n**Default:** none\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nPort at which the WebLogic Server host is listening for connection requests from the plug-in (or from other servers). (If you are using SSL between the plug-in and WebLogic Server, set this parameter to the SSL listen port and set the SecureProxy parameter to ON).\n\nIf you are using a WebLogic Cluster, use the WebLogicCluster parameter instead of WebLogicPort.\n\n8.1.21 WLCookieName\n\n**Default:** JSESSIONID\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nIf you change the name of the WebLogic Server session cookie in the WebLogic Server Web application, then you must change the WLCookieName parameter in the plug-in to the same value. The name of the WebLogic session cookie is set in the WebLogic-specific deployment descriptor, in the `<session-descriptor>` element in weblogic.xml.\n\n8.1.22 WLDNSRefreshInterval\n\n**Default:** 0 (Lookup once, during startup)\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server\n\nIf defined in the proxy configuration, specifies number of seconds interval at which WebLogic Server refreshes DNS name to IP mapping for a server. This can be used if a WebLogic Server instance is migrated to a different IP address, but the DNS name for that server’s IP remains the same. In this case, at the specified refresh interval the DNS<->IP mapping will be updated.\n\n8.1.23 WLEexcludePathOrMimeType\n\n**Default:** none\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\nThis parameter allows you to exclude certain requests from proxying. This parameter can be defined locally at the Location tag level and globally. When the property is defined locally, it does not override the global property but defines a union of the two parameters.\n\n8.1.24 WLFlushChunks\n\n**Default:** False\n\n**Applies to:** Microsoft IIS\n\nBy default, IIS plug-in buffers chunked transfer encoding responses instead of streaming the chunks as they are received. When the flag `WLFlushChunks` is set to true, the plug-in flushes chunks immediately as they are received from WebLogic Server.\n\n8.1.25 WLForwardUriUnparsed\n\n**Default:** OFF\n\n**Applies to:** Oracle HTTP Server, Apache HTTP Server\n\nWhen set to ON, the WLS plug-in will forward the original URI from the client to WebLogic Server. When set to OFF (default), the URI sent to WebLogic Server is subject to modification by mod_rewrite or other web server plug-in modules.\n\n8.1.26 WLIOTimeoutSecs\n\nNew name for `HungServerRecoverSecs`.\n\n**Default:** 300\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nDefines the amount of time the plug-in waits for a response to a request from WebLogic Server. The plug-in waits for `WLIOTimeoutSecs` for the server to respond and then declares that server dead, and fails over to the next server. The value should be set to a very large value. If the value is less than the time the servlets take to process, then you may see unexpected results.\n\nMinimum value: 10\n\nMaximum value: Unlimited\n\n8.1.27 WLLocalIP\n\n**Default:** none\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\n Defines the IP address (on the plug-in's system) to bind to when the plug-in connects to a WebLogic Server instance running on a multihomed machine.\n\nIf `WLLocalIP` is not set, then the TCP/IP stack will choose the source IP address.\n\n8.1.28 WLLogFile\n\n**Default:** See the `Debug` parameter\n\n**Applies to:** Microsoft IIS\nSpecifies path and file name for the log file that is generated when the Debug parameter is set to ON. You must create this directory before setting this parameter.\n\nFor information on setting logging without using the deprecated parameter, see Deprecated Directives for Apache HTTP Server.\n\n8.1.29 WLMaxWebSocketClients\n\nDefault: Windows: Half of ThreadsPerChild, Non-Windows: Half of MaxRequestWorkers (or MaxClients for Apache 2.2)\nApplies to: Oracle HTTP Server, Apache HTTP Server\nLimits the number of active WebSocket connections at any instant of time.\n\nNote:\nThe maximum value you can set for this parameter is 75 percent of ThreadsPerChild (Windows) or 75 percent of MaxRequestWorkers (or MaxClients for Apache 2.2, non-Windows). If the value specified for this parameter is greater than the maximum allowed, it will be automatically lowered to that maximum.\n\n8.1.30 WLProxyPassThrough\n\nDefault: OFF\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\nIf you have a chained proxy setup, where a proxy plug-in or HttpClusterServlet is running behind some other proxy or load balancer, you must explicitly enable the WLProxyPassThrough parameter. This parameter allows the header to be passed through the chain of proxies.\n\n8.1.31 WLProxySSL\n\nDefault: OFF\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\nSet this parameter to ON to maintain SSL communication between the plug-in and WebLogic Server when the following conditions exist:\n\n• An HTTP client request specifies the HTTPS protocol\n• The request is passed through one or more proxy servers (including the Oracle WebLogic Server Proxy Plug-In)\n• The connection between the plug-in and WebLogic Server uses the HTTP protocol\n\nWhen WLProxySSL is set to ON, the location header returned to the client from WebLogic Server specifies the HTTPS protocol.\n\n8.1.32 WLProxySSLPassThrough\n\nDefault: OFF\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nIf a load balancer or other software deployed in front of the web server and plug-in is the SSL termination point, and that product sets the WL-Proxy-SSL request header to true or false based on whether the client connected to it over SSL, set WLProxySSLPassThrough to ON so that the use of SSL is passed on to the Oracle WebLogic Server.\n\nIf the SSL termination point is in the web server where the plug-in operates, or the load balancer does not set WL-Proxy-SSL, set WLProxySSLPassThrough to OFF (default).\n\n8.1.33 WLRetryAfterDroppedConnection\n\nDefault: ALL\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nTells the Apache plug-in which requests to retry when a connection is lost before WLS sends the status line. Valid arguments are:\n\n- ALL: All requests will be retried.\n- IDEMPOTENT: Only requests using idempotent methods will be retried.\n- NONE: No requests will be retried.\n\n8.1.34 WLSendHdrSeparately\n\nDefault: ON\n\nApplies to: Microsoft IIS\n\nWhen this parameter is set to ON, the header and body of the response are sent in separate packets.\n\nNote:\n\nIf you must send the header and body of the response in two calls, for example, in cases where you have other ISAPI filters or programmatic clients that expect headers before the body, set this parameter to ON.\n\n8.1.35 WLServerInitiatedFailover\n\nDefault: ON\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nThis controls whether a 503 error response from Oracle WebLogic Server triggers a failover to another server. Normally, the plug-in will attempt to failover to another server when a 503 error response is received. When WLServerInitiatedFailover is set to OFF, the 503 error response will be returned to the client immediately.\n\n8.1.36 WLSocketTimeoutSecs\n\nDefault: 2 (must be greater than 0)\n8.1.37 WLSRequest\n\nDefault: OFF\n\nApplies to: Oracle HTTP Server, Apache HTTP Server\n\nThis is an alternative to the WLSRequest On mechanism of identifying requests to be forwarded to Oracle WebLogic Server. For example,\n\n```xml\n<Location /weblogic>\n WLSRequest ON\n PathTrim /weblogic\n</Location>\n```\n\nThe use of WLSRequest ON instead of SetHandler weblogic-handler has the following advantages:\n\n- Lower web server processing overhead in general\n- Resolves substantial performance degradation when the web server DocumentRoot is on a slow filesystem\n- Resolves 403 errors for URIs which cannot be mapped to the filesystem due to the filesystem length restrictions\n\n8.1.38 WLTempDir\n\nDefault: See the Debug parameter\n\nApplies to: Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nFor Oracle HTTP Server, Apache HTTP Server and Oracle iPlanet HTTP Server, this directive specifies the location of the _wl_proxy directory for POST data files.\n\nFor Microsoft IIS, this directive specifies the directory where a wlproxy.log will be created. If the location fails, the Plug-In resorts to creating the log file under C:/temp. It also specifies the location of the _wl_proxy directory for POST data files. When both WLTempDir and WLLLogFile are set, WLLLogFile will override the location of wlproxy.log. WLTempDir will still determine the location of _wl_proxy directory.\n\n8.2 SSL Parameters for Web Server Plug-Ins\n\nNote:\n\nSCG Certificates are not supported for use with Oracle WebLogic Server Proxy Plug-In. Non-SCG certificates work appropriately and allow SSL communication between WebLogic Server and the plug-in.\n\nKeyStore-related initialization parameters are not supported for use with Oracle WebLogic Server Proxy Plug-In.\nThe SSL parameters for Web Server plug-ins are described in the following sections.\nParameters are case sensitive.\n\n- **SecureProxy**\n- **WebLogicSSLVersion**\n- **WLSSLWallet**\n\n### 8.2.1 SecureProxy\n\n**Default:** OFF\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\n\nSet this parameter to ON to enable the use of the SSL protocol for all communication between the plug-in and WebLogic Server. Remember to configure a port on the corresponding WebLogic Server for the SSL protocol before defining this parameter.\n\nThis parameter may be set at two levels: in the configuration for the main server and—if you have defined any virtual hosts—in the configuration for the virtual host. The configuration for the virtual host inherits the SSL configuration from the configuration of the main server if the setting is not overridden in the configuration for the virtual host.\n\n### 8.2.2 WebLogicSSLVersion\n\n**Default:** The best protocol supported by both the plug-in and WebLogic Server.\n\n**Applies to:** Oracle HTTP Server, Apache HTTP Server\n\nSpecifies the SSL protocol version to use for communication between the plug-in and the WebLogic Server. This setting does not need to match that of the web server’s `ssl.conf` file. Plug-in can have its own SSL version to communicate with WebLogic Server.\n\nThe following values are accepted:\n\n- **TLSv1**: Uses TLS v1.0\n- **TLSv1_1**: Uses TLS v1.1\n- **TLSv1_2**: Uses TLS v1.2\n\nFor example:\n\n```\nWebLogicSSLVersion TLSv1_1 TLSv1_2\n```\n\nYou can define multiple protocols by using a space-separated list. The SSL protocol version chosen is used for all the connections from the plug-in to WebLogic Server. Hence define this parameter at the global scope.\n\nIf not configured, the plug-in uses the best protocol supported by both the plug-in and WebLogic Server.\n\n### 8.2.3 WLSSLWallet\n\n**Default:** none\n\n**Applies to:** Oracle HTTP Server, Oracle iPlanet Web Server, Apache HTTP Server, Microsoft IIS\nWLSSLWallet performs one-way or two-way SSL based on how SSL is configured for Oracle WebLogic Server.\n\nRequires the path of an Oracle Wallet (containing an SSO wallet file) as an argument. For example:\n\n```\nWLSSLWallet \"${ORACLE_INSTANCE}/config/fmwconfig/components/$ {COMPONENT_TYPE}/instances/${COMPONENT_NAME}/keystores/default\"\n```\n\n### 8.3 Location of POST Data Files\n\nWhen the FileCaching parameter is set to ON, and the size of the POST data in a request is greater than 2048 bytes, the POST data is first read into a temporary file on disk and then forwarded to the WebLogic Server in chunks of 8192 bytes. This preserves the POST data during failover.\n\nThe temporary POST file is located under `/tmp/_wl_proxy` for UNIX. For Windows it is located as follows (if `WLTempDir` is not specified):\n\n1. Environment variable `TMP`\n2. Environment variable `TEMP`\n3. `C:\\Temp`\n\n`/tmp/_wl_proxy` is a fixed directory and is owned by the HTTP Server user. When there are multiple HTTP Servers installed by different users, some HTTP Servers might not be able to write to this directory. This condition results in an error.\n\nTo correct this condition, use the `WLTempDir` parameter to specify a different location for the `_wl_proxy` directory for POST data files."}}},{"rowIdx":53,"cells":{"id":{"kind":"string","value":"c1e732571eb0bf562555300065ac29f08d0d7058"},"text":{"kind":"string","value":"Copyright © 2023 Amazon Web Services, Inc. and/or its affiliates. All rights reserved.\n\nAmazon's trademarks and trade dress may not be used in connection with any product or service that is not Amazon's, in any manner that is likely to cause confusion among customers, or in any manner that disparages or discredits Amazon. All other trademarks not owned by Amazon are the property of their respective owners, who may or may not be affiliated with, connected to, or sponsored by Amazon.\nTable of Contents\n\nWhat are the AWS Tools for PowerShell? ................................................................. 1\nMaintenance and support for SDK major versions ........................................... 1\nAWS . Tools ............................................................................................................. 1\nAWSPowerShell.NetCore ...................................................................................... 2\nAWSPowerShell ..................................................................................................... 2\nHow to use this guide ............................................................................................ 3\nInstallation ............................................................................................................. 4\nPrerequisites .......................................................................................................... 4\nInstalling on Windows ............................................................................................ 5\n Prerequisites .......................................................................................................... 6\n Install AWS . Tools ............................................................................................... 6\n Install AWSPowerShell.NetCore ....................................................................... 7\n Install AWSPowerShell ..................................................................................... 8\n Enable Script Execution .................................................................................... 9\n Versioning ........................................................................................................... 10\nUpdating AWS Tools for PowerShell ..................................................................... 11\nInstalling on Linux or macOS .............................................................................. 12\n Overview of Setup ............................................................................................... 12\n Prerequisites .......................................................................................................... 6\n Install AWS . Tools ............................................................................................... 13\n Install AWSPowerShell.NetCore ....................................................................... 14\n Script Execution ................................................................................................. 14\n Configuring the PowerShell Console ............................................................... 16\n Initialize Your PowerShell Session .................................................................. 16\n Versioning ........................................................................................................... 10\nUpdating the AWS Tools for PowerShell on Linux or macOS ........................... 17\nRelated Information ............................................................................................. 18\nMigrating from AWS Tools for PowerShell Version 3.3 to Version 4 ............... 18\n New Fully Modularized AWS . Tools Version ................................................... 18\n New Get-AWSService cmdlet ........................................................................... 18\n New -Select Parameter to Control the Object Returned by a Cmdlet ............. 19\n More Consistent Limiting of the Number of Items in the Output .................... 20\n Easier to Use Stream Parameters ..................................................................... 20\n Extending the Pipe by Property Name .............................................................. 21\n Static Common Parameters .............................................................................. 21\n AWS . Tools Declares and Enforces Mandatory Parameters ......................... 21\n All Parameters Are Nullable ............................................................................ 21\n Removing Previously Deprecated Features ...................................................... 22\nAWS Account and Access Keys ............................................................................ 22\n To get your access key ID and secret access key .............................................. 22\nGetting Started .................................................................................................... 24\nAWS Credentials ................................................................................................... 24\n Credentials Store Locations ............................................................................. 24\n Managing Profiles ............................................................................................... 25\n Specifying Credentials ...................................................................................... 26\n Credentials Search Order ................................................................................... 28\n Credential Handling in AWS Tools for PowerShell Core ................................ 28\nShared Credentials ............................................................................................... 29\n Using an IAM Role with AWS Tools for PowerShell ....................................... 30\n Using the Credential Profile Types ................................................................... 31\n The ProfilesLocation Common Parameter ...................................................... 31\n Displaying Your Credential Profiles ................................................................ 32\n Removing Credential Profiles ......................................................................... 32\n Important Notes ................................................................................................. 32\nAWS Regions ................................................................. 33\nSpecifying a Custom or Nonstandard Endpoint .......................... 34\nCmdlet Discovery and Aliases ............................................. 34\nCmdlet Discovery ......................................................... 34\nCmdlet Naming and Aliases ............................................. 38\nPiplining and $AWSHistory ............................................. 41\n$AWSHistory ............................................................. 41\nConfiguring Federated Identity ......................................... 44\nPrerequisites ............................................................... 44\nHow an Identity-Federated User Gets Federated Access to AWS Service APIs 44\nHow SAML Support Works in the AWS Tools for PowerShell ... 45\nHow to Use the PowerShell SAML Configuration Cmdlets ........ 46\nAdditional Reading ...................................................... 50\nUsing the AWS Tools for PowerShell ................................... 51\nPowerShell File Concatenation Encoding ............................... 51\nReturned Objects for the PowerShell Tools ............................. 51\nAmazon EC2 ............................................................... 52\nAmazon S3 ....................................................................... 52\nIAM and AWS Tools for PowerShell ................................... 52\nAWS Lambda and AWS Tools for PowerShell ......................... 52\nAmazon SNS and Amazon SQS ......................................... 52\nCloudWatch .................................................................... 53\nSee Also .......................................................................... 53\nTopics ............................................................................. 53\nAmazon S3 and Tools for Windows PowerShell ......................... 53\nCreate an Amazon S3 Bucket, Verify Its Region, and Optionally Remove It 54\nConfigure an Amazon S3 Bucket as a Website and Enable Logging 54\nUpload Objects to an Amazon S3 Bucket ............................... 55\nDelete Amazon S3 Objects and Buckets ................................. 56\nUpload In-Line Text Content to Amazon S3 ............................ 57\nIAM and Tools for PowerShell ........................................... 58\nCreate New IAM Users and Groups ..................................... 58\nSet an IAM Policy for an IAM User ................................... 59\nSet an Initial Password for an IAM User ............................... 60\nAmazon EC2 and Tools for Windows PowerShell ...................... 60\nCreate a Key Pair ........................................................... 60\nCreate a Security Group ................................................... 62\nFind an AMI ................................................................. 65\nLaunch an Instance ......................................................... 67\nAWS Lambda and AWS Tools for PowerShell ......................... 70\nPrerequisites ..................................................................... 6\nInstall the AWSLambdaPSCore Module ................................ 71\nSee Also .......................................................................... 53\nAmazon SQS, Amazon SNS and Tools for Windows PowerShell 71\nCreate an Amazon SQS queue and get queue ARN ................... 72\nCreate an Amazon SNS topic .............................................. 72\nGive permissions to the SNS topic ....................................... 72\nSubscribe the queue to the SNS topic ................................. 73\nGive permissions ............................................................ 73\nVerify results .................................................................... 73\nCloudWatch from the AWS Tools for Windows PowerShell ....... 74\nPublish a Custom Metric to Your CloudWatch Dashboard ........ 74\nSee Also .......................................................................... 53\nUsing ClientConfig .......................................................... 75\nUsing the ClientConfig parameter ...................................... 75\nUsing an undefined property .............................................. 75\nSpecifying the AWS Region ............................................... 76\nWhat are the AWS Tools for PowerShell?\n\nThe AWS Tools for PowerShell are a set of PowerShell modules that are built on the functionality exposed by the AWS SDK for .NET. The AWS Tools for PowerShell enable you to script operations on your AWS resources from the PowerShell command line.\n\nThe cmdlets provide an idiomatic PowerShell experience for specifying parameters and handling results even though they are implemented using the various AWS service HTTP query APIs. For example, the cmdlets for the AWS Tools for PowerShell support PowerShell pipelining—that is, you can pipe PowerShell objects in and out of the cmdlets.\n\nThe AWS Tools for PowerShell are flexible in how they enable you to handle credentials, including support for the AWS Identity and Access Management (IAM) infrastructure. You can use the tools with IAM user credentials, temporary security tokens, and IAM roles.\n\nThe AWS Tools for PowerShell support the same set of services and AWS Regions that are supported by the SDK. You can install the AWS Tools for PowerShell on computers running Windows, Linux, or macOS operating systems.\n\n**Note**\n\nAWS Tools for PowerShell version 4 is the latest major release, and is a backward-compatible update to AWS Tools for PowerShell version 3.3. It adds significant improvements while maintaining existing cmdlet behavior. Your existing scripts should continue to work after upgrading to the new version, but we do recommend that you test them thoroughly before upgrading. For more information about the changes in version 4, see Migrating from AWS Tools for PowerShell Version 3.3 to Version 4 (p. 18).\n\nThe AWS Tools for PowerShell are available as the following three distinct packages:\n\n- AWS.Tools (p. 1)\n- AWSPowerShell.NetCore (p. 2)\n- AWSPowerShell (p. 2)\n\nMaintenance and support for SDK major versions\n\nFor information about maintenance and support for SDK major versions and their underlying dependencies, see the following in the AWS SDKs and Tools Reference Guide:\n\n- AWS SDKs and tools maintenance policy\n- AWS SDKs and tools version support matrix\n\nAWS.Tools - A modularized version of the AWS Tools for PowerShell\nThis version of AWS Tools for PowerShell is the recommended version for any computer running PowerShell in a production environment. Because it’s modularized, you need to download and load only the modules for the services you want to use. This reduces download times, memory usage, and enables auto-importing of AWS.Tools cmdlets with the need to manually call Import-Module first.\n\nThis is the latest version of AWS Tools for PowerShell and runs on all supported operating systems, including Windows, Linux, and macOS. This package provides one installation module, AWS.Tools.Installer, one common module, AWS.Tools.Common, and one module for each AWS service, for example, AWS.Tools.EC2, AWS.Tools.IAM, AWS.Tools.S3, and so on.\n\nThe AWS.Tools.Installer module provides cmdlets that enable you to install, update, and remove the modules for each of the AWS services. The cmdlets in this module automatically ensure that you have all the dependent modules required to support the modules you want to use.\n\nThe AWS.Tools.Common module provides cmdlets for configuration and authentication that are not service specific. To use the cmdlets for an AWS service, you just run the command. PowerShell automatically imports the AWS.Tools.Common module and the module for the AWS service whose cmdlet you want to run. This module is automatically installed if you use the AWS.Tools.Installer module to install the service modules.\n\nYou can install this version of AWS Tools for PowerShell on computers that are running:\n\n- PowerShell Core 6.0 or later on Windows, Linux, or macOS.\n- Windows PowerShell 5.1 or later on Windows with the .NET Framework 4.7.2 or later.\n\nThroughout this guide, when we need to specify this version only, we refer to it by its module name: AWS.Tools.\n\n### AWSPowerShell.NetCore - A single-module version of the AWS Tools for PowerShell\n\nThis version consists of a single, large module that contains support for all AWS services. Before you can use this module, you must manually import it.\n\nYou can install this version of AWS Tools for PowerShell on computers that are running:\n\n- PowerShell Core 6.0 or later on Windows, Linux, or macOS.\n- Windows PowerShell 3.0 or later on Windows with the .NET Framework 4.7.2 or later.\n\nThroughout this guide, when we need to specify this version only, we refer to it by its module name: AWSPowerShell.NetCore.\n\n### AWSPowerShell - A single-module version for Windows PowerShell\n\nYou can install this version of AWS Tools for PowerShell on computers that are running:\n\n- PowerShell Core 6.0 or later on Windows, Linux, or macOS.\n- Windows PowerShell 3.0 or later on Windows with the .NET Framework 4.7.2 or later.\n\nThroughout this guide, when we need to specify this version only, we refer to it by its module name: AWSPowerShell.\nThis version of AWS Tools for PowerShell is compatible with and installable on only Windows computers that are running Windows PowerShell versions 2.0 through 5.1. It is not compatible with PowerShell Core 6.0 or later, or any other operating system (Linux or macOS). This version consists of a single, large module that contains support for all AWS services.\n\nThroughout this guide, when we need to specify this version only, we refer to it by its module name: *AWSPowerShell*.\n\n**How to use this guide**\n\nThe guide is divided into the following major sections.\n\n**Installing the AWS Tools for PowerShell (p. 4)**\n\nThis section explains how to install the AWS Tools for PowerShell. It includes how to sign up for AWS if you don't already have an account, and how to create an IAM user that you can use to run the cmdlets.\n\n**Getting Started with the AWS Tools for Windows PowerShell (p. 24)**\n\nThis section describes the fundamentals of using the AWS Tools for PowerShell, such as specifying credentials and AWS Regions, finding cmdlets for a particular service, and using aliases for cmdlets.\n\n**Using the AWS Tools for PowerShell (p. 51)**\n\nThis section includes information about using the AWS Tools for PowerShell to perform some of the most common AWS tasks.\nPrerequisites for Setting up the AWS Tools for PowerShell\n\nTo use the AWS Tools for PowerShell, you must first complete the following steps.\n\n1. Sign up for an AWS account.\n \n If you don't have an AWS account, see the following topic for complete instructions on how to sign up:\n \n\n2. Create an IAM user.\n \n After you sign up for your account, you must create users in the AWS Identity and Access Management (IAM) service. Each user has its own credentials and permissions. The credentials are used to authenticate the user making a request. The permissions determine which AWS resources and operations are authorized for that user.\n\n Creating a user is outside the scope of this topic. But if you're new to AWS, we recommend that you read the following:\n \n - To understand user credentials and best practices for managing them, see [AWS Security Credentials](https://docs.aws.amazon.com/credentails/) in the Amazon Web Services General Reference.\n\n3. Create an access key for your IAM user.\n \n The AWS Tools for PowerShell require that each cmdlet is sent using appropriate security credentials. To do this, you typically must create an access key for each user that needs to use the AWS Tools for PowerShell cmdlets. An access key consists of an access key ID and secret access key. These are used to sign (encrypt for the purpose of authentication) programmatic requests that you make to AWS services. If you don’t have an access key, you can create it by using the IAM console at [https://console.aws.amazon.com/iam/](https://console.aws.amazon.com/iam/). As described in [AWS Security Credentials](https://docs.aws.amazon.com/credentails/), we recommend...\nthat you use access keys for IAM users instead of AWS root account access keys. IAM lets you securely control access to AWS services and resources in your AWS account.\n\nAs with any AWS operation, creating access keys requires that you have permissions to perform the related IAM actions. For more information, see Permissions for Administering IAM Identities in the IAM User Guide.\n\nAfter you create the access key for your first user in the AWS console, you can use that user and its access key to run AWS Tools for PowerShell cmdlets to create access keys for your other users. The following example shows how to use the New-IAMAccessKey cmdlet to create an access key and secret key for an IAM user.\n\n```\nPS > New-IAMAccessKey -UserName alice\nAccessKeyId : AKIAIOSFODNN7EXAMPLE\nCreateDate : 9/4/19 12:46:18 PM\nSecretAccessKey : wJalrXUtnFEMI/K7MDENG/bPxRFiCYEXAMPLEKEY\nStatus : Active\nUserName : alice\n```\n\nSave these credentials in a safe place. You need them to configure the AWS Tools for PowerShell credentials file later. For more information, see Using AWS Credentials (p. 24).\n\n**Important**\n\nThe only time you can see the secret access key (the equivalent of a password) is when you create the access key. You cannot retrieve it later. If you lose the secret key, you must delete the access key/secret key pair and recreate them.\n\nAn IAM user can have only two access keys at any one time. If you attempt to create a third set, the New-IAMAccessKey cmdlet returns an error. To create another, you must first delete one of the existing two.\n\nYou can use the Remove-IAMAccessKey cmdlet to delete a set of credentials for an IAM user. You must specify both the UserName and the AccessKeyId.\n\n```\nPS > Remove-IAMAccessKey -UserName alice -AccessKeyId AKIAIOSFODNN7EXAMPLE\nConfirm\nAre you sure you want to perform this action?\nPerforming the operation \"Remove-IAMAccessKey (DeleteAccessKey)\" on target \"AKIAIOSFODNN7EXAMPLE\".\n[Y] Yes [A] Yes to All [N] No [L] No to All [S] Suspend [?] Help (default is \"Y\"):\ny\n```\n\n**Installing the AWS Tools for PowerShell on Windows**\n\nA Windows-based computer can run any of the AWS Tools for PowerShell package options:\n\n- **AWS.Tools (p. 6)** - The modularized version of AWS Tools for PowerShell. Each AWS service is supported by its own individual, small module, with shared support modules AWS.Tools.Common and AWS.Tools.Installer.\n- **AWSPowerShell.NetCore (p. 7)** - The single, large-module version of AWS Tools for PowerShell. All AWS services are supported by this single, large module.\n- **AWSPowerShell (p. 8)** - The legacy Windows-specific, single, large-module version of AWS Tools for PowerShell. All AWS services are supported by this single, large module.\nThe package you choose depends on the release and edition of Windows that you’re running.\n\n**Note** \nThe Tools for Windows PowerShell (AWS PowerShell module) are installed by default on all Windows-based Amazon Machine Images (AMIs).\n\nSetting up the AWS Tools for PowerShell involves the following high-level tasks, described in detail in this topic.\n\n1. Install the AWS Tools for PowerShell package option that’s appropriate for your environment.\n2. Verify that script execution is enabled by running the `Get-ExecutionPolicy` cmdlet.\n3. Import the AWS Tools for PowerShell module into your PowerShell session.\n\n**Prerequisites**\n\nEnsure that you meet the requirements listed in [Prerequisites for Setting up the AWS Tools for PowerShell](p. 4).\n\nNewer versions of PowerShell, including PowerShell Core, are available as downloads from Microsoft at [Installing various versions of PowerShell](on Microsoft's Web site).\n\n**Install AWS Tools on Windows**\n\nYou can install the modularized version of AWS Tools for PowerShell on computers that are running Windows with Windows PowerShell 5.1, or PowerShell Core 6.0 or later. For information about how to install PowerShell Core, see [Installing various versions of PowerShell](on Microsoft's Web site).\n\nYou can install AWS.Tools in one of three ways:\n\n- Using the cmdlets in the AWS.Tools module. The AWS.Tools.Installer module simplifies the installation and update of other AWS.Tools modules. The AWS.Tools.Installer requires, automatically downloads and installs, an updated version of PowerShellGet. The AWS.Tools.Installer module and automatically keeps your module versions in sync. When you install or update to a newer version of one module, the cmdlets in the AWS.Tools.Installer automatically update all of your other AWS.Tools modules to the same version.\n\n- Downloading the modules from [AWS.Tools.zip](and extracting them in one of the module folders. You can discover your module folders by printing the value of the $Env:PSModulePath variable.\n\n- Installing each service module from the PowerShell Gallery using the `Install-Module` cmdlet, as described in the following procedure.\n\n**To install AWS.Tools on Windows using the Install-Module cmdlet**\n\n1. Start a PowerShell session.\n\n **Note** \n We recommend that you don’t run PowerShell as an administrator with elevated permissions except when required by the task at hand. This is because of the potential security risk and is inconsistent with the principle of least privilege.\n\n2. To install the modularized AWS.Tools package, run the following command.\n\n ```powershell\n PS > Install-Module -Name AWS.Tools.Installer\n Untrusted repository\n You are installing the modules from an untrusted repository. If you trust this repository, change its InstallationPolicy value by running the Set-PSRepository cmdlet. Are you sure\n ```\nyou want to install the modules from 'PSGallery'? [Y] Yes [A] Yes to All [N] No [L] No to All [S] Suspend [?] Help (default is \"N\"): y\n\nIf you are notified that the repository is \"untrusted\", it asks you if you want to install anyway. Enter y to allow PowerShell to install the module. To avoid the prompt and install the module without trusting the repository, you can run the command with the -Force parameter.\n\nPS > Install-Module -Name AWS.Tools.Installer -Force\n\n3. You can now install the module for each AWS service that you want to use by using the Install-AWSToolsModule cmdlet. For example, the following command installs the IAM module. This command also installs any dependent modules that are required for the specified module to work. For example, when you install your first AWS.Tools service module, it also installs AWS.Tools.Common. This is a shared module required by all AWS service modules. It also removes older versions of the modules, and updates other modules to the same newer version.\n\nPS > Install-AWSToolsModule AWS.Tools.EC2, AWS.Tools.S3 -CleanUp\n\nConfirm\nAre you sure you want to perform this action?\nPerforming the operation \"Install-AWSToolsModule\" on target \"AWS Tools version 4.0.0.0\".\n[Y] Yes [A] Yes to All [N] No [L] No to All [S] Suspend [?] Help (default is \"Y\"):\n\nInstalling module AWS.Tools.Common version 4.0.0.0\nInstalling module AWS.Tools.EC2 version 4.0.0.0\nInstalling module AWS.Tools.Glacier version 4.0.0.0\nInstalling module AWS.Tools.S3 version 4.0.0.0\n\nUninstalling AWS.Tools version 3.3.618.0\nUninstalling module AWS.Tools.Glacier\nUninstalling module AWS.Tools.S3\nUninstalling module AWS.Tools.SimpleNotificationService\nUninstalling module AWS.Tools.SQS\nUninstalling module AWS.Tools.Common\n\nNote\nThe Install-AWSToolsModule cmdlet downloads all requested modules from the PSRepository named PSGallery (https://www.powershellgallery.com/) and considers it a trusted source. Use the command Get-PSRepository -Name PSGallery for more information about this PSRepository.\n\nBy default, this command installs modules into the $home\\Documents\\PowerShell\\Modules folder. To install the AWS Tools for PowerShell for all users of a computer, you must run the following command in a PowerShell session that you started as an administrator. This installs modules to the $env:ProgramFiles\\PowerShell\\Modules folder that is accessible by all users.\n\nPS > Install-AWSToolsModule AWS.Tools.IdentityManagement -Scope AllUsers\n\nInstall AWSPowerShell.NetCore on Windows\n\nYou can install the AWSPowerShell.NetCore on computers that are running Windows with PowerShell version 3 through 5.1, or PowerShell Core 6.0 or later. For information about how to install PowerShell Core, see Installing various versions of PowerShell on the Microsoft PowerShell website.\n\nYou can install AWSPowerShell.NetCore in one of two ways\nTo install AWSPowerShell.NetCore from the PowerShell Gallery using the Install-Module cmdlet\n\nTo install the AWSPowerShell.NetCore from the PowerShell Gallery, your computer must be running PowerShell 5.0 or later, or running PowerShellGet on PowerShell 3 or later. Run the following command.\n\n```\nPS > Install-Module -name AWSPowerShell.NetCore\n```\n\nIf you’re running PowerShell as administrator, the previous command installs AWS Tools for PowerShell for all users on the computer. If you’re running PowerShell as a standard user without administrator permissions, that same command installs AWS Tools for PowerShell for only the current user.\n\nTo install for only the current user when that user has administrator permissions, run the command with the -Scope CurrentUser parameter set, as follows.\n\n```\nPS > Install-Module -name AWSPowerShell.NetCore -Scope CurrentUser\n```\n\nAlthough PowerShell 3.0 and later releases typically load modules into your PowerShell session the first time you run a cmdlet in the module, the AWSPowerShell.NetCore module is too large to support this functionality. You must instead explicitly load the AWSPowerShell.NetCore Core module into your PowerShell session by running the following command.\n\n```\nPS > Import-Module AWSPowerShell.NetCore\n```\n\nTo load the AWSPowerShell.NetCore module into a PowerShell session automatically, add that command to your PowerShell profile. For more information about editing your PowerShell profile, see About Profiles in the PowerShell documentation.\n\nInstall AWSPowerShell on Windows PowerShell\n\nYou can install the AWS Tools for Windows PowerShell in one of three ways:\n\n- Downloading the module from AWSPowerShell.zip and extracting it in one of the module directories. You can discover your module directories by printing the value of the $Env:PSModulePath variable.\n- Running the Tools for Windows PowerShell installer. This method of installing AWSPowerShell is deprecated and we recommend that you use Install-Module instead.\n- Installing from the PowerShell Gallery using the Install-Module cmdlet as described in the following procedure.\n\nTo install AWSPowerShell from the PowerShell Gallery using the Install-Module cmdlet\n\nYou can install the AWSPowerShell from the PowerShell Gallery if you're running PowerShell 5.0 or later, or have installed PowerShellGet on PowerShell 3 or later. You can install and update AWSPowerShell from Microsoft's PowerShell Gallery by running the following command.\n\n```\nPS > Install-Module -Name AWSPowerShell\n```\nTo load the AWSPowerShell module into a PowerShell session automatically, add the previous `import-module` cmdlet to your PowerShell profile. For more information about editing your PowerShell profile, see [About Profiles](#) in the PowerShell documentation.\n\n**Note**\nThe Tools for Windows PowerShell are installed by default on all Windows-based Amazon Machine Images (AMIs).\n\n## Enable Script Execution\n\nTo load the AWS Tools for PowerShell modules, you must enable PowerShell script execution. To enable script execution, run the `Set-ExecutionPolicy` cmdlet to set a policy of RemoteSigned. For more information, see [About Execution Policies](#) on the Microsoft Technet website.\n\n**Note**\nThis is a requirement only for computers that are running Windows. The `ExecutionPolicy` security restriction is not present on other operating systems.\n\n### To enable script execution\n\n1. Administrator rights are required to set the execution policy. If you are not logged in as a user with administrator rights, open a PowerShell session as Administrator. Choose **Start**, and then choose **All Programs**. Choose **Accessories**, and then choose **Windows PowerShell**. Right-click **Windows PowerShell**, and on the context menu, choose **Run as administrator**.\n\n2. At the command prompt, enter the following.\n\n ```powershell\n PS > Set-ExecutionPolicy RemoteSigned\n ```\n\n **Note**\n On a 64-bit system, you must do this separately for the 32-bit version of PowerShell, **Windows PowerShell (x86)**.\n\nIf you don’t have the execution policy set correctly, PowerShell shows the following error whenever you try to run a script, such as your profile.\n\n```\nFile C:\\Users\\username\\Documents\\WindowsPowerShell\\Microsoft.PowerShell_profile.ps1 cannot be loaded because the execution of scripts is disabled on this system. Please see \"get-help about_signing\" for more details.\n```\n\nAt line:1 char:2\n+ . <<<< 'C:\\Users\\username\\Documents\\WindowsPowerShell\\Microsoft.PowerShell_profile.ps1'\n + CategoryInfo : NotSpecified: (:) [], PSSecurityException\n + FullyQualifiedErrorId : RuntimeException\n\nThe Tools for Windows PowerShell installer automatically updates the **PSModulePath** to include the location of the directory that contains the AWSPowerShell module.\n\nBecause the **PSModulePath** includes the location of the AWS module's directory, the `Get-Module -ListAvailable` cmdlet shows the module.\n\n```\nPS > Get-Module -ListAvailable\nModuleType Name ExportedCommands\n---------- ---- ----------------\nManifest AppLocker {}\nManifest BitsTransfer {}\nManifest PSDiagnostics {}\nManifest TroubleshootingPack {}\n```\nAWS releases new versions of the AWS Tools for PowerShell periodically to support new AWS services and features. To determine the version of the Tools that you have installed, run the `Get-AWSPowerShellVersion` cmdlet.\n\n### Versioning\n\nTo determine the version of PowerShell that you are running, enter `$PSVersionTable` to view the contents of the `$PSVersionTable` automatic variable.\nUpdating the AWS Tools for PowerShell on Windows\n\nPeriodically, as updated versions of the AWS Tools for PowerShell are released, you should update the version that you are running locally.\n\nUpdate the Modularized AWS.Tools\n\nTo upgrade your AWS.Tools modules to the latest version, run the following command.\n\n```powershell\nPS > Update-AWSToolsModule -CleanUp\n```\n\nThis command updates all of the currently installed AWS.Tools modules and, after a successful update, removes other installed versions.\n\n**Note**\nThe Update-AWSToolsModule cmdlet downloads all modules from the PSRepository named PSGallery ([https://www.powershellgallery.com/](https://www.powershellgallery.com/)) and considers it a trusted source. Use the command: Get-PSRepository -Name PSGallery for more information on this PSRepository.\n\nUpdate the Tools for PowerShell Core\n\nRun the Get-AWSPowerShellVersion cmdlet to determine the version that you are running, and compare that with the version of Tools for Windows PowerShell that is available on the PowerShell Gallery website. We suggest you check every two to three weeks. Support for new commands and AWS services is available only after you update to a version with that support.\n\nBefore you install a newer release of AWSPowerShell.NetCore, uninstall the existing module. Close any open PowerShell sessions before you uninstall the existing package. Run the following command to uninstall the package.\n\n```powershell\nPS > Uninstall-Module -Name AWSPowerShell.NetCore -AllVersions\n```\n\nAfter the package is uninstalled, install the updated module by running the following command.\n\n```powershell\nPS > Install-Module -Name AWSPowerShell.NetCore\n```\n\nAfter installation, run the command Import-Module AWSPowerShell.NetCore to load the updated cmdlets into your PowerShell session.\n\nUpdate the Tools for Windows PowerShell\n\nRun the Get-AWSPowerShellVersion cmdlet to determine the version that you are running, and compare that with the version of Tools for Windows PowerShell that is available on the PowerShell Gallery website. We suggest you check every two to three weeks. Support for new commands and AWS services is available only after you update to a version with that support.\n\n- If you installed by using the Install-Module cmdlet, run the following commands.\nInstalling on Linux or macOS\n\nOverview of Setup\n\nTo install AWS Tools for PowerShell on a Linux or macOS computer, you can choose from two package options:\n\n- **AWS.Tools** (p. 13) – The modularized version of AWS Tools for PowerShell. Each AWS service is supported by its own individual, small module, with shared support modules AWS.Tools.Common.\n- **AWSPowerShell.NetCore** (p. 14) – The single, large-module version of AWS Tools for PowerShell. All AWS services are supported by this single, large module.\n\nSetting either of these up on a computer running Linux or macOS involves the following tasks, described in detail later in this topic:\n\n1. Install PowerShell Core 6.0 or later on a supported system.\n2. After installing PowerShell Core, start PowerShell by running pwsh in your system shell.\n3. Install either AWS.Tools or AWSPowerShell.NetCore.\n4. Run the appropriate Import-Module cmdlet to import the module into your PowerShell session.\n5. Run the Initialize-AWSDefaultConfiguration cmdlet to provide your AWS credentials.\n\nPrerequisites\n\nEnsure that you meet the requirements listed on Prerequisites for Setting up the AWS Tools for PowerShell (p. 4).\n\nTo run the AWS Tools for PowerShell Core, your computer must be running PowerShell Core 6.0 or later.\n\n- For a list of supported Linux platform releases and for information about how to install the latest version of PowerShell on a Linux-based computer, see Installing PowerShell on Linux on Microsoft's website. Some Linux-based operating systems, such as Arch, Kali, and Raspbian, are not officially supported, but have varying levels of community support.\nInstall AWS.Tools on Linux or macOS\n\nYou can install the modularized version of AWS Tools for PowerShell on computers that are running PowerShell Core 6.0 or later. For information about how to install PowerShell Core, see Installing various versions of PowerShell on the Microsoft PowerShell website.\n\nYou can install AWS.Tools in one of three ways:\n\n• Using the cmdlets in the AWS.Tools.Installer module. The AWS.Tools.Installer module simplifies the installation and update of other AWS.Tools modules. AWS.Tools.Installer requires, automatically downloads and installs, an updated version of PowerShellGet. The AWS.Tools.Installer module also automatically keeps your module versions in sync. When you install or update to a newer version of one module, the cmdlets in the AWS.Tools.Installer automatically update all of your other AWS.Tools modules to the same version.\n\n• Downloading the modules from AWS.Tools.zip and extracting them in one of the module directories. You can discover your module directories by printing the value of the $Env:PSModulePath variable.\n\n• Installing each service module from the PowerShell Gallery using the Install-Module cmdlet, as described in the following procedure.\n\nTo install AWS.Tools on Linux or macOS using the Install-Module cmdlet\n\n1. Start a PowerShell Core session by running the following command.\n\n ```\n $ pwsh\n ```\n\n **Note**\n We recommend that you don’t run PowerShell as an administrator with elevated permissions except when required by the task at hand. This is because of the potential security risk and is inconsistent with the principle of least privilege.\n\n2. To install the modularized AWS.Tools package using the AWS.Tools.Installer module, run the following command.\n\n ```\n PS > Install-Module -Name AWS.Tools.Installer\n ```\n\n Untrusted repository\n You are installing the modules from an untrusted repository. If you trust this repository, change its InstallationPolicy value by running the Set-PSRepository cmdlet. Are you sure you want to install the modules from 'PSGallery'? [Y] Yes [A] Yes to All [N] No [L] No to All [S] Suspend [?] Help (default is \"N\"): y\n\n If you are notified that the repository is \"untrusted\", you’re asked if you want to install anyway. Enter y to allow PowerShell to install the module. To avoid the prompt and install the module without trusting the repository, you can run the following command.\n\n ```\n PS > Install-Module -Name AWS.Tools.Installer -Force\n ```\n\n3. You can now install the module for each service that you want to use. For example, the following command installs the IAM module. This command also installs any dependent modules that are\nrequired for the specified module to work. For example, when you install your first AWS.Tools service module, it also installs AWS.Tools.Common. This is a shared module required by all AWS service modules. It also removes older versions of the modules, and updates other modules to the same newer version.\n\n```\nPS > Install-AWSToolsModule AWS.Tools.EC2,AWS.Tools.S3 -CleanUp\nConfirm\nAre you sure you want to perform this action?\n Performing the operation \"Install-AWSToolsModule\" on target \"AWS Tools version 4.0.0.0\".\n [Y] Yes [A] Yes to All [N] No [L] No to All [S] Suspend [?] Help (default is \"Y\"):\n\n Installing module AWS.Tools.Common version 4.0.0.0\n Installing module AWS.Tools.EC2 version 4.0.0.0\n Installing module AWS.Tools.Glacier version 4.0.0.0\n Installing module AWS.Tools.S3 version 4.0.0.0\n\n Uninstalling AWS.Tools version 3.3.618.0\n Uninstalling module AWS.Tools.Glacier\n Uninstalling module AWS.Tools.S3\n Uninstalling module AWS.Tools.SimpleNotificationService\n Uninstalling module AWS.Tools.SQS\n Uninstalling module AWS.Tools.Common\n```\n\n**Note**\n\nThe `Install-AWSToolsModule` cmdlet downloads all requested modules from the PSRepository named PSGallery ([https://www.powershellgallery.com/](https://www.powershellgallery.com/)) and considers the repository as a trusted source. Use the command `Get-PSRepository -Name PSGallery` for more information about this PSRepository.\n\nBy default, this installs modules into the `$home\\Documents\\PowerShell\\Modules` folder. To install the AWS.Tools module for all users of a computer, you must run the following command in a PowerShell session that you started as an administrator. This installs modules to the `$env:ProgramFiles\\PowerShell\\Modules` folder that is accessible by all users.\n\n```\nPS > Install-AWSToolsModule -Name AWS.Tools.IdentityManagement -Scope AllUsers\n```\n\n**Install AWSPowerShell.NetCore on Linux or macOS**\n\nTo upgrade to a newer release of AWSPowerShell.NetCore, follow the instructions in [Updating the AWS Tools for PowerShell on Linux or macOS](#) (p. 17). Uninstall earlier versions of AWSPowerShell.NetCore first.\n\nYou can install AWSPowerShell.NetCore in one of two ways:\n\n- **Download**ing the module from `AWSPowerShell.NetCore.zip` and extracting it in one of the module directories. You can discover your module directories by printing the value of the `$Env:PSModulePath` variable.\n\n- **Installing** from the PowerShell Gallery using the `Install-Module` cmdlet as described in the following procedure.\n\n**To install AWSPowerShell.NetCore on Linux or macOS using the Install-Module cmdlet**\n\nStart a PowerShell Core session by running the following command.\n$ pwsh\n\n**Note**\n\nWe recommend that you *don't* start PowerShell by running `sudo pwsh` to run PowerShell with elevated, administrator rights. This is because of the potential security risk and is inconsistent with the principle of least privilege.\n\nTo install the AWSPowerShell.NetCore single-module package from the PowerShell Gallery, run the following command.\n\n```\nPS > Install-Module -Name AWSPowerShell.NetCore\n```\n\nUntrusted repository\n\nYou are installing the modules from an untrusted repository. If you trust this repository, change its InstallationPolicy value by running the `Set-PSRepository` cmdlet. Are you sure you want to install the modules from 'PSGallery'? [Y] Yes [A] Yes to All [N] No [L] No to All [S] Suspend [?] Help (default is \"N\"): y\n\nIf you are notified that the repository is \"untrusted\", you're asked if you want to install anyway. Enter `y` to allow PowerShell to install the module. To avoid the prompt without trusting the repository, you can run the following command.\n\n```\nPS > Install-Module -Name AWSPowerShell.NetCore -Force\n```\n\nYou don't have to run this command as root, unless you want to install the AWS Tools for PowerShell for all users of a computer. To do this, run the following command in a PowerShell session that you have started with `sudo pwsh`.\n\n```\nPS > Install-Module -Scope AllUsers -Name AWSPowerShell.NetCore -Force\n```\n\n**Script Execution**\n\nThe `Set-ExecutionPolicy` command isn't available on non-Windows systems. You can run `Get-ExecutionPolicy`, which shows that the default execution policy setting in PowerShell Core running on non-Windows systems is `Unrestricted`. For more information, see About Execution Policies on the Microsoft Technet website.\n\nBecause the `PSModulePath` includes the location of the AWS module's directory, the `Get-Module -ListAvailable` cmdlet shows the module that you installed.\n\n**AWS.Tools**\n\n```\nPS > Get-Module -ListAvailable\n```\n\nDirectory: `/Users/username/.local/share/powershell/Modules`\n\n<table>\n<thead>\n<tr>\n<th>ModuleType</th>\n<th>Version</th>\n<th>Name</th>\n<th>PSEdition</th>\n<th>ExportedCommands</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Binary</td>\n<td>3.3.563.1</td>\n<td>AWS.Tools.Common</td>\n<td>Desk</td>\n<td>(Clear-AWSHistory, Get-AWSHistoryConfiguration, Initialize-AWSDefaultConfiguration, Clear-AWSDefaultConfigurat...</td>\n</tr>\n</tbody>\n</table>\n\n**AWSPowerShell.NetCore**\n\n```\nPS > Get-Module -ListAvailable\n```\n\nDirectory: `/Users/username/.local/share/powershell/Modules`\nConfigure a PowerShell Console to Use the AWS Tools for PowerShell Core (AWSPowerShell.NetCore Only)\n\nPowerShell Core typically loads modules automatically whenever you run a cmdlet in the module. But this doesn't work for AWSPowerShell.NetCore because of its large size. To start running AWSPowerShell.NetCore cmdlets, you must first run the `Import-Module AWSPowerShell.NetCore` command. This isn't required for cmdlets in AWS.Tools modules.\n\nInitialize Your PowerShell Session\n\nWhen you start PowerShell on a Linux-based or macOS-based system after you have installed the AWS Tools for PowerShell, you must run `Initialize-AWSDefaultConfiguration` to specify which AWS access key to use. For more information about `Initialize-AWSDefaultConfiguration`, see Using AWS Credentials (p. 24).\n\nNote\nIn earlier (before 3.3.96.0) releases of the AWS Tools for PowerShell, this cmdlet was named `Initialize-AWSDefaults`.\n\nVersioning\n\nAWS releases new versions of the AWS Tools for PowerShell periodically to support new AWS services and features. To determine the version of the AWS Tools for PowerShell that you have installed, run the `Get-AWSPowerShellVersion` cmdlet.\n\n```\nPS > Get-AWSPowerShellVersion\n\nTools for PowerShell\nVersion 4.0.123.0\nCopyright 2012-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.\n\nAmazon Web Services SDK for .NET\nCore Runtime Version 3.3.103.22\nCopyright 2009-2015 Amazon.com, Inc. or its affiliates. All Rights Reserved.\n\nRelease notes: https://github.com/aws/aws-tools-for-powershell/blob/master/CHANGELOG.md\n\nThis software includes third party software subject to the following copyrights:\n- Logging from log4net, Apache License\n [http://logging.apache.org/log4net/license.html]\n\nTo see a list of the supported AWS services in the current version of the tools, add the -ListServiceVersionInfo parameter to a `Get-AWSPowerShellVersion` cmdlet.\n\nTo determine the version of PowerShell that you are running, enter `$PSVersionTable` to view the contents of the `$PSVersionTable` automatic variable.\n\n```\nPS > $PSVersionTable\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n```\nUpdating the AWS Tools for PowerShell on Linux or macOS\n\nPeriodically, as updated versions of the AWS Tools for PowerShell are released, you should update the version that you're running locally.\n\nUpdate the Modularized AWS.Tools.*\n\nTo upgrade your AWS.Tools modules to the latest version, run the following command.\n\n```\nPS > Update-AWSToolsModule -CleanUp\n```\n\nThis command updates all of the currently installed AWS.Tools modules and, for those modules that were successfully updated, removes the earlier versions.\n\n**Note**\n\nThe Update-AWSToolsModule cmdlet downloads all modules from the PSRepository named PSGallery ([https://www.powershellgallery.com/](https://www.powershellgallery.com/)) and considers it a trusted source. Use the command `Get-PSRepository -Name PSGallery` for more information about this PSRepository.\n\nUpdate the Tools for PowerShell Core\n\nRun the Get-AWSPowerShellVersion cmdlet to determine the version that you are running, and compare that with the version of Tools for Windows PowerShell that is available on the PowerShell Gallery website. We suggest you check every two to three weeks. Support for new commands and AWS services is available only after you update to a version with that support.\n\nBefore you install a newer release of AWSPowerShell.NetCore, uninstall the existing module. Close any open PowerShell sessions before you uninstall the existing package. Run the following command to uninstall the package.\n\n```\nPS > Uninstall-Module -Name AWSPowerShell.NetCore -AllVersions\n```\n\nAfter the package is uninstalled, install the updated module by running the following command.\n\n```\nPS > Install-Module -Name AWSPowerShell.NetCore\n```\n\nAfter installation, run the command `Import-Module AWSPowerShell.NetCore` to load the updated cmdlets into your PowerShell session.\n\nRelated Information\n\n- [Getting Started with the AWS Tools for Windows PowerShell (p. 24)]\nMigrating from AWS Tools for PowerShell Version 3.3 to Version 4\n\nAWS Tools for PowerShell version 4 is a backward-compatible update to AWS Tools for PowerShell version 3.3. It adds significant improvements while maintaining existing cmdlet behavior.\n\nYour existing scripts should continue to work after upgrading to the new version, but we do recommend that you test them thoroughly before upgrading your production environments.\n\nThis section describes the changes and explains how they might impact your scripts.\n\nNew Fully Modularized AWS.Tools Version\n\nThe AWSPowerShell.NetCore and AWSPowerShell packages were \"monolithic\". This meant that all of the AWS services were supported in the same module, making it very large, and growing larger as each new AWS service and feature was added. The new AWS.Tools package is broken up into smaller modules that give you the flexibility to download and install only those that you require for the AWS services that you use. The package includes a shared AWS.Tools.Common module that is required by all of the other modules, and an AWS.Tools.Installer module that simplifies installing, updating, and removing modules as needed.\n\nThis also enables auto-importing of cmdlets on first call, without having to first call Import-module. However, to interact with the associated .NET objects before calling a cmdlet, you must still call Import-Module to let PowerShell know about the relevant .NET types.\n\nFor example, the following command has a reference to Amazon.EC2.Model.Filter. This type of reference can't trigger auto-importing, so you must call Import-Module first or the command fails.\n\n```\nPS> $filter = [Amazon.EC2.Model.Filter]@{Name=\"vpc-id\";Values=\"vpc-1234abcd\"}\nInvalidOperationException: Unable to find type [Amazon.EC2.Model.Filter].\nPS> Import-Module AWS.Tools.EC2\nPS> $filter = [Amazon.EC2.Model.Filter]@{Name=\"vpc-id\";Values=\"vpc-1234abcd\"}\nPS> Get-EC2Instance -Filter $filter -Select Reservations.Instances.InstanceId\ni-0123456789abcdefg\ni-0123456789hijklmn\n```\n\nNew Get-AWSService cmdlet\n\nTo help you discover the names of the modules for each AWS service in the AWS.Tools collection of modules, you can use the Get-AWSService cmdlet.\n\n```\nPS> Get-AWSService\nService : ACMPCA\nCmdletNounPrefix : PCA\nModuleName : AWS.Tools.ACMPCA\nSDKAssemblyVersion : 3.3.101.56\nServiceName : Certificate Manager Private Certificate Authority\nPS> Get-AWSService\nService : AlexaForBusiness\n```\nNew -Select Parameter to Control the Object Returned by a Cmdlet\n\nMost cmdlets in version 4 support a new -Select parameter. Each cmdlet calls the AWS service APIs for you using the AWS SDK for .NET. Then the AWS Tools for PowerShell client converts the response into an object that you can use in your PowerShell scripts and pipe to other commands. Sometimes the final PowerShell object has more fields or properties in the original response than you need, and other times you might want the object to include fields or properties of the response that are not there by default. The -Select parameter enables you to specify what is included in the .NET object returned by the cmdlet.\n\nFor example, the `Get-S3Object` cmdlet invokes the Amazon S3 SDK operation `ListObjects`. That operation returns a `ListObjectsResponse` object. However, by default, the `Get-S3Object` cmdlet returns only the `S3Objects` element of the SDK response to the PowerShell user. In the following example, that object is an array with two elements.\n\n```powershell\nPS > Get-S3Object -BucketName mybucket\nETag : \"01234567890123456789012345678901111\"\nBucketName : mybucket\nKey : file1.txt\nLastModified : 9/30/2019 1:31:40 PM\nOwner : Amazon.S3.Model.Owner\nSize : 568\nStorageClass : STANDARD\n\nETag : \"01234567890123456789012345678902222\"\nBucketName : mybucket\nKey : file2.txt\nLastModified : 7/15/2019 9:36:54 AM\nOwner : Amazon.S3.Model.Owner\nSize : 392\nStorageClass : STANDARD\n```\n\nIn AWS Tools for PowerShell version 4, you can specify `-Select *` to return the complete .NET response object returned by the SDK API call.\n\n```powershell\nPS > Get-S3Object -BucketName mybucket -Select *\nIsTruncated : False\nNextMarker :\nS3Objects : {file1.txt, file2.txt}\nName : mybucket\nPrefix :\nMaxKeys : 1000\nCommonPrefixes :\nDelimiter :\n```\n\nYou can also specify the path to the specific nested property you want. The following example returns only the Key property of each element in the S3Objects array.\n\n```powershell\nPS > Get-S3Object -BucketName mybucket -Select S3Objects.Key\nfile1.txt\n```\nIn certain situations it can be useful to return a cmdlet parameter. You can do this with -Select ^ParameterName. This feature supplants the -PassThru parameter, which is still available but deprecated.\n\n```powershell\nPS > Get-S3Object -BucketName mybucket -Select S3Objects.Key | > Write-S3ObjectTagSet -Select ^Key -BucketName mybucket -Tagging_TagSet @{ Key='key'; Value='value'}\nfile1.txt\nfile2.txt\n```\n\nThe reference topic for each cmdlet identifies whether it supports the -Select parameter.\n\n**More Consistent Limiting of the Number of Items in the Output**\n\nEarlier versions of AWS Tools for PowerShell enabled you to use the -MaxItems parameter to specify the maximum number of objects returned in the final output.\n\nThis behavior is removed from AWS.Tools.\n\nThis behavior is deprecated in AWSPowerShell.NetCore and AWSPowerShell, and will be removed from those versions in a future release.\n\nIf the underlying service API supports a MaxItems parameter, it's still available and functions as the API specifies. But it no longer has the added behavior of limiting the number of items returned in the output of the cmdlet.\n\nTo limit the number of items returned in the final output, pipe the output to the Select-Items cmdlet and specify the -First n parameter, where n is the maximum number of items to include in the final output.\n\n```powershell\nPS > Get-S3Object -BucketName mybucket -Select S3Objects.Key | select -first 1*\nfile1.txt\n```\n\nNot all AWS services supported -MaxItems in the same way, so this removes that inconsistency and the unexpected results that sometimes occurred. Also, -MaxItems combined with the new -Select (p. 19) parameter could sometimes result in confusing results.\n\n**Easier to Use Stream Parameters**\n\nParameters of type Stream or byte[] can now accept string, string[], or FileInfo values.\n\nFor example, you can use any of the following examples.\n\n```powershell\nPS > Invoke-LMFunction -FunctionName MyTestFunction -PayloadStream '{\n >> \"some\": \"json\"\n >> }'\n\nPS > Invoke-LMFunction -FunctionName MyTestFunction -PayloadStream (ls .\\some.json)\n\nPS > Invoke-LMFunction -FunctionName MyTestFunction -PayloadStream @(\"\\{\", \"some\": \"json\", \",'\\}\"\")\n```\nAWS Tools for PowerShell converts all strings to byte[] using UTF-8 encoding.\n\nExtending the Pipe by Property Name\n\nTo make the user experience more consistent, you can now pass pipeline input by specifying the property name for any parameter.\n\nIn the following example, we create a custom object with properties that have names that match the parameter names of the target cmdlet. When the cmdlet runs, it automatically consumes those properties as its parameters.\n\n```\nPS > [pscustomobject] @{ BucketName='myBucket'; Key='file1.txt'; PartNumber=1 } | Get-S3ObjectMetadata\n```\n\n**Note**\nSome properties supported this in earlier versions of AWS Tools for PowerShell. Version 4 makes this more consistent by enabling it for all parameters.\n\nStatic Common Parameters\n\nTo improve consistency in version 4.0 of AWS Tools for PowerShell, all parameters are static.\n\nIn earlier versions of AWS Tools for PowerShell, some common parameters such as AccessKey, SecretKey, ProfileName, or Region, were dynamic, while all other parameters were static. This could create problems because PowerShell binds static parameters before dynamic ones. For example, let's say you ran the following command.\n\n```\nPS > Get-EC2Region -Region us-west-2\n```\n\nEarlier versions of PowerShell bound the value us-west-2 to the -RegionName static parameter instead of the -Region dynamic parameter. Likely, this could confuse users.\n\nAWS.Tools Declares and Enforces Mandatory Parameters\n\nThe AWS.* modules now declare and enforce mandatory cmdlet parameters. When an AWS Service declares that a parameter of an API is required, PowerShell prompts you for the corresponding cmdlet parameter if you didn't specify it. This applies only to AWS. Tools. To ensure backward compatibility, this does not apply to AWSPowerShell.NetCore or AWSPowerShell.\n\nAll Parameters Are Nullable\n\nYou can now assign $null to value type parameters (numbers and dates). This change should not affect existing scripts. This enables you to bypass the prompt for a mandatory parameter. Mandatory parameters are enforced in AWS.Tools only.\n\nIf you run the following example using version 4, it effectively bypasses client-side validation because you provide a \"value\" for each mandatory parameter. However, the Amazon EC2 API service call fails because the AWS service still requires that information.\n\n```\nPS > Get-EC2InstanceAttribute -InstanceId $null -Attribute $null\nWARNING: You are passing $null as a value for parameter Attribute which is marked as required.\n```\nRemoving Previously Deprecated Features\n\nThe following features were deprecated in previous releases of AWS Tools for PowerShell and are removed in version 4:\n\n- Removed the -Terminate parameter from the Stop-EC2Instance cmdlet. Use Remove-EC2Instance instead.\n- Removed the -ProfileName parameter from the Clear-AWSCredential cmdlet. Use Remove-AWSCredentialProfile instead.\n- Removed cmdlets Import-EC2Instance and Import-EC2Volume.\n\nAWS Account and Access Keys\n\nTo access AWS, you will need to sign up for an AWS account.\n\nAccess keys consist of an access key ID and secret access key, which are used to sign programmatic requests that you make to AWS. If you don't have access keys, you can create them by using the IAM console at https://console.aws.amazon.com/iam/. We recommend that you use IAM access keys instead of AWS root account access keys. IAM lets you securely control access to AWS services and resources in your AWS account.\n\n**Note**\n\nTo create access keys, you must have permissions to perform the required IAM actions. For more information, see Granting IAM User Permission to Manage Password Policy and Credentials in the IAM User Guide.\n\n**To get your access key ID and secret access key**\n\n1. Open the IAM console at https://console.aws.amazon.com/iam/.\n2. On the navigation menu, choose Users.\n3. Choose your IAM user name (not the check box).\n4. Open the Security credentials tab, and then choose Create access key.\n5. To see the new access key, choose Show. Your credentials resemble the following:\n - Access key ID: AKIAIOSFODNN7EXAMPLE\n - Secret access key: wJalrXUttnFEMI/K7MDENG/bPxrFiCYEXAMPLEKEY\n6. To download the key pair, choose Download .csv file. Store the .csv file with keys in a secure location.\n\n**Important**\n\n- Keep the keys confidential to protect your AWS account, and never email them. Do not share them outside your organization, even if an inquiry appears to come from AWS or Amazon.com. No one who legitimately represents Amazon will ever ask you for your secret key.\nYou can retrieve the secret access key **only** when you initially create the key pair. Like a password, you can't retrieve it later. If you lose it, you must create a new key pair.\n\n**Related topics**\n\n- **What Is IAM?** in the *IAM User Guide*.\n- **AWS Security Credentials** in the *Amazon Web Services General Reference*.\nGetting Started with the AWS Tools for Windows PowerShell\n\nThis section describes fundamentals of using the Tools for Windows PowerShell. For example, it explains how to specify which credentials and AWS Region the Tools for Windows PowerShell should use when interacting with AWS. This section also provides guidance for using standard PowerShell cmdlets such as Get-Command to discover AWS cmdlets.\n\nTopics\n\n• Using AWS Credentials (p. 24)\n• Shared Credentials in AWS Tools for PowerShell (p. 29)\n• Specifying AWS Regions (p. 33)\n• Cmdlet Discovery and Aliases (p. 34)\n• Pipelining and $AWSHistory (p. 41)\n• Configuring Federated Identity with the AWS Tools for PowerShell (p. 44)\n\nUsing AWS Credentials\n\nEach AWS Tools for PowerShell command must include a set of AWS credentials, which are used to cryptographically sign the corresponding web service request. You can specify credentials per command, per session, or for all sessions.\n\nAs a best practice, to avoid exposing your credentials, do not put literal credentials in a command. Instead, create a profile for each set of credentials that you want to use, and store the profile in either of two credential stores. Specify the correct profile by name in your command, and the AWS Tools for PowerShell retrieves the associated credentials. For a general discussion of how to safely manage AWS credentials, see Best Practices for Managing AWS Access Keys in the Amazon Web Services General Reference.\n\nNote\nYou need an AWS account to get credentials and use the AWS Tools for PowerShell. For information about how to sign up for an account, see AWS Account and Access Keys (p. 22).\n\nTopics\n\n• Credentials Store Locations (p. 24)\n• Managing Profiles (p. 25)\n• Specifying Credentials (p. 26)\n• Credentials Search Order (p. 28)\n• Credential Handling in AWS Tools for PowerShell Core (p. 28)\n\nCredentials Store Locations\n\nThe AWS Tools for PowerShell can use either of two credentials stores:\n\n• The AWS SDK store, which encrypts your credentials and stores them in your home folder. In Windows, this store is located at: C:\\Users\\username\\AppData\\Local\\AWSToolkit\\RegisteredAccounts.json.\n\nThe AWS SDK for .NET and Toolkit for Visual Studio can also use the AWS SDK store.\n• The shared credentials file, which is also located in your home folder, but stores credentials as plain text.\n\nBy default, the credentials file is stored here:\n• On Windows: C:\\Users\\username\\.aws\\credentials\n• On Mac/Linux: ~/.aws/credentials\n\nThe AWS SDKs and the AWS Command Line Interface can also use the credentials file. If you're running a script outside of your AWS user context, be sure that the file that contains your credentials is copied to a location where all user accounts (local system and user) can access your credentials.\n\nManaging Profiles\n\nProfiles enable you to reference different sets of credentials with AWS Tools for PowerShell. You can use AWS Tools for PowerShell cmdlets to manage your profiles in the AWS SDK store. You can also manage profiles in the AWS SDK store by using the Toolkit for Visual Studio or programmatically by using the AWS SDK for .NET. For directions about how to manage profiles in the credentials file, see Best Practices for Managing AWS Access Keys.\n\nAdd a New profile\n\nTo add a new profile to the AWS SDK store, run the command Set-AWSCredential. It stores your access key and secret key in your default credentials file under the profile name you specify.\n\n```\nPS > Set-AWSCredential `-AccessKey AKIA0123456787EXAMPLE `-SecretKey wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY `-StoreAs MyNewProfile\n```\n\n• -AccessKey– The access key ID.\n• -SecretKey– The secret key.\n• -StoreAs– The profile name, which must be unique. To specify the default profile, use the name default.\n\nUpdate a Profile\n\nThe AWS SDK store must be maintained manually. If you later change credentials on the service—for example, by using the IAM console—running a command with the locally stored credentials fails with the following error message:\n\n```\nThe Access Key Id you provided does not exist in our records.\n```\n\nYou can update a profile by repeating the Set-AWSCredential command for the profile, and passing it the new access and secret keys.\n\nList Profiles\n\nYou can check the current list of names with the following command. In this example, a user named Shirley has access to three profiles that are all stored in the shared credentials file (~/.aws/credentials).\n\n```\nPS > Get-AWSCredential -ListProfileDetail\n```\nRemove a Profile\n\nTo remove a profile that you no longer require, use the following command.\n\n```\nPS > Remove-AWSCredentialProfile -ProfileName an-old-profile-I-do-not-need\n```\n\nThe -ProfileName parameter specifies the profile that you want to delete.\n\nThe deprecated command `Clear-AWSCredential` is still available for backward compatibility, but `Remove-AWSCredentialProfile` is preferred.\n\nSpecifying Credentials\n\nThere are several ways to specify credentials. The preferred way is to identify a profile instead of incorporating literal credentials into your command line. AWS Tools for PowerShell locates the profile using a search order that is described in [Credentials Search Order](p. 28).\n\nOn Windows, AWS credentials stored in the AWS SDK store are encrypted with the logged-in Windows user identity. They cannot be decrypted by using another account, or used on a device that's different from the one on which they were originally created. To perform tasks that require the credentials of another user, such as a user account under which a scheduled task will run, set up a credential profile, as described in the preceding section, that you can use when you log in to the computer as that user. Log in as the task-performing user to complete the credential setup steps, and create a profile that works for that user. Then log out and log in again with your own credentials to set up the scheduled task.\n\n**Note**\n\nUse the `-ProfileName` common parameter to specify a profile. This parameter is equivalent to the `-StoredCredentials` parameter in earlier AWS Tools for PowerShell releases. For backward compatibility, `-StoredCredentials` is still supported.\n\nDefault Profile (Recommended)\n\nAll AWS SDKs and management tools can find your credentials automatically on your local computer if the credentials are stored in a profile named `default`. For example, if you have a profile named `default` on the local computer, you don't have to run either the `Initialize-AWSDefaultConfiguration` cmdlet or the `Set-AWSCredential` cmdlet. The tools automatically use the access and secret key data stored in that profile. To use an AWS Region other than your default Region (the results of `Get-DefaultAWSRegion`), you can run `Set-DefaultAWSRegion` and specify a Region.\n\nIf your profile is not named `default`, but you want to use it as the default profile for the current session, run `Set-AWSCredential` to set it as the default profile.\n\nAlthough running `Initialize-AWSDefaultConfiguration` lets you specify a default profile for every PowerShell session, the cmdlet loads credentials from your custom-named profile, but overwrites the default profile with the named profile.\n\nWe recommend that you do not run `Initialize-AWSDefaultConfiguration` unless you are running a PowerShell session on an Amazon EC2 instance that was not launched with an instance profile, and you want to set up the credential profile manually. Note that the credential profile in this scenario would not contain credentials. The credential profile that results from running `Initialize-AWSDefaultConfiguration` on an EC2 instance doesn't directly store credentials, but instead\nSpecifying Credentials\n\npoints to instance metadata (that provides temporary credentials that automatically rotate). However, it does store the instance's Region. Another scenario that might require running Initialize-AWSDefaultConfiguration occurs if you want to run a call against a Region other than the Region in which the instance is running. Running that command permanently overrides the Region stored in the instance metadata.\n\n```bash\nPS > Initialize-AWSDefaultConfiguration -ProfileName MyProfileName -Region us-west-2\n```\n\n**Note**\nThe default credentials are included in the AWS SDK store under the default profile name. The command overwrites any existing profile with that name.\n\nIf your EC2 instance was launched with an instance profile, PowerShell automatically gets the AWS credentials and Region information from the instance profile. You don't need to run Initialize-AWSDefaultConfiguration. Running the Initialize-AWSDefaultConfiguration cmdlet on an EC2 instance launched with an instance profile isn't necessary, because it uses the same instance profile data that PowerShell already uses by default.\n\n**Session Profile**\n\nUse Set-AWSCredential to specify a default profile for a particular session. This profile overrides any default profile for the duration of the session. We recommend this if you want to use a custom-named profile in your session instead of the current default profile.\n\n```bash\nPS > Set-AWSCredential -ProfileName MyProfileName\n```\n\n**Note**\nIn versions of the Tools for Windows PowerShell that are earlier than 1.1, the Set-AWSCredential cmdlet did not work correctly, and would overwrite the profile specified by \"MyProfileName\". We recommend using a more recent version of the Tools for Windows PowerShell.\n\n**Command Profile**\n\nOn individual commands, you can add the `-ProfileName` parameter to specify a profile that applies to only that one command. This profile overrides any default or session profiles, as shown in the following example.\n\n```bash\nPS > Get-EC2Instance -ProfileName MyProfileName\n```\n\n**Note**\nWhen you specify a default or session profile, you can also add a `-Region` parameter to override a default or session Region. For more information, see Specifying AWS Regions (p. 33). The following example specifies a default profile and Region.\n\n```bash\nPS > Initialize-AWSDefaultConfiguration -ProfileName MyProfileName -Region us-west-2\n```\n\nBy default, the AWS shared credentials file is assumed to be in the user's home folder (C:\\Users \\username\\.aws on Windows, or ~/.aws on Linux). To specify a credentials file in a different location, include the `-ProfileLocation` parameter and specify the credentials file path. The following example specifies a non-default credentials file for a specific command.\n\n```bash\nPS > Get-EC2Instance -ProfileName MyProfileName -ProfileLocation C:\\aws_service_credentials \\credentials\n```\nNote\nIf you are running a PowerShell script during a time that you are not normally signed in to AWS—for example, you are running a PowerShell script as a scheduled task outside of your normal work hours—add the -ProfileLocation parameter when you specify the profile that you want to use, and set the value to the path of the file that stores your credentials. To be certain that your AWS Tools for PowerShell script runs with the correct account credentials, you should add the -ProfileLocation parameter whenever your script runs in a context or process that does not use an AWS account. You can also copy your credentials file to a location that is accessible to the local system or other account that your scripts use to perform tasks.\n\nCredentials Search Order\n\nWhen you run a command, AWS Tools for PowerShell searches for credentials in the following order. It stops when it finds usable credentials.\n\n1. Literal credentials that are embedded as parameters in the command line.\n - We strongly recommend using profiles instead of putting literal credentials in your command lines.\n\n2. A specified profile name or profile location.\n - If you specify only a profile name, the command looks for the specified profile in the AWS SDK store and, if that does not exist, the specified profile from the AWS shared credentials file in the default location.\n - If you specify only a profile location, the command looks for the default profile from that credentials file.\n - If you specify both a name and a location, the command looks for the specified profile in that credentials file.\n\n If the specified profile or location is not found, the command throws an exception. Search proceeds to the following steps only if you did not specify a profile or location.\n\n3. Credentials specified by the -Credential parameter.\n\n4. The session profile, if one exists.\n\n5. The default profile, in the following order:\n - The default profile in the AWS SDK store.\n - The default profile in the AWS shared credentials file.\n - The AWS PS Default profile in the AWS SDK store.\n\n6. If the command is running on an Amazon EC2 instance that is configured to use an IAM role, the EC2 instance's temporary credentials accessed from the instance profile.\n\n For more information about using IAM roles for Amazon EC2 instances, see the AWS SDK for .NET.\n\nIf this search fails to locate the specified credentials, the command throws an exception.\n\nCredential Handling in AWS Tools for PowerShell Core\n\nCmdlets in AWS Tools for PowerShell Core accept AWS access and secret keys or the names of credential profiles when they run, similarly to the AWS Tools for Windows PowerShell. When they run on Windows, both modules have access to the AWS SDK for .NET credential store file (stored in the per-user AppData \\Local\\AWSToolkit\\RegisteredAccounts.json file).\n\nThis file stores your keys in encrypted format, and cannot be used on a different computer. It is the first file that the AWS Tools for PowerShell searches for a credential profile, and is also the file where the\nAWS Tools for PowerShell stores credential profiles. For more information about the AWS SDK for .NET credential store file, see Configuring AWS Credentials. The Tools for Windows PowerShell module does not currently support writing credentials to other files or locations.\n\nBoth modules can read profiles from the AWS shared credentials file that is used by other AWS SDKs and the AWS CLI. On Windows, the default location for this file is C:\\Users\\<userid>\\.aws\\credentials. On non-Windows platforms, this file is stored at ~/.aws/credentials. The -ProfileLocation parameter can be used to point to a non-default file name or file location.\n\nThe SDK credential store holds your credentials in encrypted form by using Windows cryptographic APIs. These APIs are not available on other platforms, so the AWS Tools for PowerShell Core module uses the AWS shared credentials file exclusively, and supports writing new credential profiles to the shared credential file.\n\nThe following example scripts that use the Set-AWSCredential cmdlet show the options for handling credential profiles on Windows with either the AWSPowerShell or AWSPowerShell.NetCore modules.\n\n```powershell\n# Writes a new (or updates existing) profile with name \"myProfileName\" # in the encrypted SDK store file\nSet-AWSCredential -AccessKey akey -SecretKey skey -StoreAs myProfileName\n\n# Checks the encrypted SDK credential store for the profile and then # falls back to the shared credentials file in the default location\nSet-AWSCredential -ProfileName myProfileName\n\n# Bypasses the encrypted SDK credential store and attempts to load the # profile from the ini-format credentials file \"mycredentials\" in the # folder C:\\MyCustomPath\nSet-AWSCredential -ProfileName myProfileName -ProfileLocation C:\\MyCustomPath\\mycredentials\n```\n\nThe following examples show the behavior of the AWSPowerShell.NetCore module on the Linux or macOS operating systems.\n\n```powershell\n# Writes a new (or updates existing) profile with name \"myProfileName\" # in the default shared credentials file ~/.aws/credentials\nSet-AWSCredential -AccessKey akey -SecretKey skey -StoreAs myProfileName\n\n# Writes a new (or updates existing) profile with name \"myProfileName\" # into an ini-format credentials file \"~/.mystepath/mycredentials\"\nSet-AWSCredential -AccessKey akey -SecretKey skey -StoreAs myProfileName -ProfileLocation ~/.mystepath/mycredentials\n\n# Reads the default shared credential file looking for the profile \"myProfileName\"\nSet-AWSCredential -ProfileName myProfileName\n\n# Reads the specified credential file looking for the profile \"myProfileName\"\nSet-AWSCredential -ProfileName myProfileName -ProfileLocation ~/.mystepath/mycredentials\n```\n\n## Shared Credentials in AWS Tools for PowerShell\n\nThe Tools for Windows PowerShell support the use of the AWS shared credentials file, similarly to the AWS CLI and other AWS SDKs. The Tools for Windows PowerShell now support reading\nand writing of basic, session, and assume role credential profiles to both the .NET credentials file and the AWS shared credential file. This functionality is enabled by a new Amazon.Runtime.CredentialManagement namespace.\n\nThe new profile types and access to the AWS shared credential file are supported by the following parameters that have been added to the credentials-related cmdlets, Initialize-AWSDefaultConfiguration, New-AWSCredential, and Set-AWSCredential. In service cmdlets, you can refer to your profiles by adding the common parameter, -ProfileName.\n\n### Using an IAM Role with AWS Tools for PowerShell\n\nThe AWS shared credential file enables additional types of access. For example, you can access your AWS resources by using an IAM role instead of the long term credentials of an IAM user. To do this, you must have a standard profile that has permissions to assume the role. When you tell the AWS Tools for PowerShell to use a profile that specified a role, the AWS Tools for PowerShell looks up the profile identified by the SourceProfile parameter. Those credentials are used to request temporary credentials for the role specified by the RoleArn parameter. You can optionally require the use of an multi-factor authentication (MFA) device or an ExternalId code when the role is assumed by a third party.\n\n<table>\n<thead>\n<tr>\n<th>Parameter Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ExternalId</td>\n<td>The user-defined external ID to be used when assuming a role, if required by the role. This is typically only required when you delegate access to your account to a third party. The third party must include the ExternalId as a parameter when assuming the assigned role. For more information, see <a href=\"https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_rolesets_externalid.html\">How to Use an External ID When Granting Access to Your AWS Resources to a Third Party</a> in the IAM User Guide.</td>\n</tr>\n<tr>\n<td>MfaSerial</td>\n<td>The MFA serial number to be used when assuming a role, if required by the role. For more information, see <a href=\"https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_rolesets_mfa.html\">Using Multi-Factor Authentication (MFA) in AWS</a> in the IAM User Guide.</td>\n</tr>\n<tr>\n<td>RoleArn</td>\n<td>The ARN of the role to assume for assume role credentials. For more information about creating and using roles, see <a href=\"https://docs.aws.amazon.com/IAM/latest/UserGuide/using-iam-creating-spool_about.html\">IAM Roles</a> in the IAM User Guide.</td>\n</tr>\n<tr>\n<td>SourceProfile</td>\n<td>The name of the source profile to be used by assume role credentials. The credentials found in this profile are used to assume the role specified by the RoleArn parameter.</td>\n</tr>\n</tbody>\n</table>\n\n### Setup of profiles for assuming a role\n\nThe following is an example showing how to set up a source profile that enables directly assuming an IAM role.\n\nThe first command creates a source profile that is referenced by the role profile. The second command creates the role profile that which role to assume. The third command shows the credentials for the role profile.\nAWS Tools for PowerShell User Guide\n\nUsing the Credential Profile Types\n\nTo set a credential profile type, understand which parameters provide the information required by the profile type.\n\n<table>\n<thead>\n<tr>\n<th>Credentials Type</th>\n<th>Parameters you must use</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Basic</td>\n<td>-AccessKey</td>\n</tr>\n<tr>\n<td></td>\n<td>-SecretKey</td>\n</tr>\n<tr>\n<td>Session:</td>\n<td>-AccessKey</td>\n</tr>\n<tr>\n<td></td>\n<td>-SecretKey</td>\n</tr>\n<tr>\n<td></td>\n<td>-SessionToken</td>\n</tr>\n<tr>\n<td>Role:</td>\n<td>-SourceProfile</td>\n</tr>\n<tr>\n<td></td>\n<td>-RoleArn</td>\n</tr>\n<tr>\n<td></td>\n<td>optional: -ExternalId</td>\n</tr>\n<tr>\n<td></td>\n<td>optional: -MfaSerial</td>\n</tr>\n</tbody>\n</table>\n\nThe ProfilesLocation Common Parameter\n\nYou can use the -ProfileLocation parameter to write to the shared credential file as well as instruct a cmdlet to read from the credential file. Adding the -ProfileLocation parameter controls whether Tools for\nDisplaying Your Credential Profiles\n\nWindows PowerShell uses the shared credential file or the .NET credential file. The following table describes how the parameter works in Tools for Windows PowerShell.\n\n<table>\n<thead>\n<tr>\n<th>Profile Location Value</th>\n<th>Profile Resolution Behavior</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>null (not set) or empty</td>\n<td>First, search the .NET credential file for a profile with the specified name. If the profile isn't found, search the AWS shared credentials file at (user's home directory).aws\\credentials.</td>\n</tr>\n<tr>\n<td>The path to a file in the AWS shared credential file format</td>\n<td>Search only the specified file for a profile with the given name.</td>\n</tr>\n</tbody>\n</table>\n\nSave Credentials to a Credentials File\n\nTo write and save credentials to one of the two credential files, run the `Set-AWSCredential` cmdlet. The following example shows how to do this. The first command uses `Set-AWSCredential` with `-ProfileLocation` to add access and secret keys to a profile specified by the `-ProfileName` parameter. In the second line, run the `Get-Content` cmdlet to display the contents of the credentials file.\n\n```\nPS > Set-AWSCredential -ProfileLocation C:\\Users\\auser\\.aws\\credentials -ProfileName basic_profile -AccessKey access_key2 -SecretKey secret_key2\nPS > Get-Content C:\\Users\\auser\\.aws\\credentials\naws_access_key_id=access_key2\naws_secret_access_key=secret_key2\n```\n\nDisplaying Your Credential Profiles\n\nRun the `Get-AWSCredential` cmdlet and add the `-ListProfileDetail` parameter to return credential file types and locations, and a list of profile names.\n\n```\nPS > Get-AWSCredential -ListProfileDetail\n```\n\n```\n<table>\n<thead>\n<tr>\n<th>ProfileName</th>\n<th>StoreTypeName</th>\n<th>ProfileLocation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>source_profile</td>\n<td>NetSDKCredentialsFile</td>\n<td></td>\n</tr>\n<tr>\n<td>assume_role_profile</td>\n<td>NetSDKCredentialsFile</td>\n<td></td>\n</tr>\n<tr>\n<td>basic_profile</td>\n<td>SharedCredentialsFile</td>\n<td>C:\\Users\\auser.aws\\credentials</td>\n</tr>\n</tbody>\n</table>\n```\n\nRemoving Credential Profiles\n\nTo remove credential profiles, run the new `Remove-AWSCredentialProfile` cmdlet. `Clear-AWSCredential` is deprecated, but still available for backward compatibility.\n\nImportant Notes\n\nOnly `Initialize-AWSDefaultConfiguration`, `New-AWSCredential`, and `Set-AWSCredential` support the parameters for role profiles. You cannot specify the role parameters directly on a command such as `Get-S3Bucket -SourceProfile source_profile_name -RoleArn arn:aws:iam::999999999999:role/role_name`. That does not work because service cmdlets do not directly support the SourceProfile or RoleArn parameters. Instead, you must store those parameters in a profile, then call the command with the `-ProfileName` parameter.\nSpecifying AWS Regions\n\nThere are two ways to specify the AWS Region to use when running AWS Tools for PowerShell commands:\n\n- Use the `-Region` common parameter on individual commands.\n- Use the `Set-DefaultAWSRegion` command to set a default Region for all commands.\n\nMany AWS cmdlets fail if the Tools for Windows PowerShell can't figure out what Region to use. Exceptions include cmdlets for Amazon S3 (p. 53), Amazon SES, and IAM and Tools for PowerShell (p. 58), which automatically default to a global endpoint.\n\nTo specify the region for a single AWS command\n\nAdd the `-Region` parameter to your command, such as the following.\n\n```\nPS > Get-EC2Image -Region us-west-2\n```\n\nTo set a default region for all AWS CLI commands in the current session\n\nFrom the PowerShell command prompt, type the following command.\n\n```\nPS > Set-DefaultAWSRegion -Region us-west-2\n```\n\n**Note**\n\nThis setting persists only for the current session. To apply the setting to all of your PowerShell sessions, add this command to your PowerShell profile as you did for the `Import-Module` command.\n\nTo view the current default region for all AWS CLI commands\n\nFrom the PowerShell command prompt, type the following command.\n\n```\nPS > Get-DefaultAWSRegion\n```\n\n<table>\n<thead>\n<tr>\n<th>Region</th>\n<th>Name</th>\n<th>IsShellDefault</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>us-west-2</td>\n<td>US West (Oregon)</td>\n<td>True</td>\n</tr>\n</tbody>\n</table>\n\nTo clear the current default Region for all AWS CLI commands\n\nFrom the PowerShell command prompt, type the following command.\n\n```\nPS > Clear-DefaultAWSRegion\n```\n\nTo view a list of all available AWS Regions\n\nFrom the PowerShell command prompt, type the following command. The third column in the sample output identifies which Region is the default for your current session.\n\n```\nPS > Get-AWSRegion\n```\n\n<table>\n<thead>\n<tr>\n<th>Region</th>\n<th>Name</th>\n<th>IsShellDefault</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ap-east-1</td>\n<td>Asia Pacific (Hong Kong)</td>\n<td>False</td>\n</tr>\n</tbody>\n</table>\nSpecifying a Custom or Nonstandard Endpoint\n\nSpecify a custom endpoint as a URL by adding the -EndpointUrl common parameter to your Tools for Windows PowerShell command, in the following sample format.\n\n```\nPS > Some-AWS-PowerShellCmdlet -EndpointUrl \"custom endpoint URL\" -Other -Parameters\n```\n\nThe following is an example using the Get-EC2Instance cmdlet. The custom endpoint is in the us-west-2, or US West (Oregon) Region in this example, but you can use any other supported AWS Region, including regions that are not enumerated by Get-AWSRegion.\n\n```\nPS > Get-EC2Instance -EndpointUrl \"https://service-custom-url.us-west-2.amazonaws.com\" -InstanceID \"i-0555a30a2000000e1\"\n```\n\nCmdlet Discovery and Aliases\n\nThis section shows you how to list services that are supported by the AWS Tools for PowerShell, how to show the set of cmdlets provided by the AWS Tools for PowerShell in support of those services, and how to find alternative cmdlet names (also called aliases) to access those services.\n\nCmdlet Discovery\n\nAll AWS service operations (or APIs) are documented in the API Reference Guide for each service. For example, see the IAM API Reference. There is, in most cases, a one-to-one correspondence between an AWS service API and an AWS PowerShell cmdlet. To get the cmdlet name that corresponds to an AWS service API name, run the AWS Get-AWSCmdletName cmdlet with the -ApiOperation parameter and the AWS service API name. For example, to get all possible cmdlet names that are based on any available DescribeInstances AWS service API, run the following command:\n\n```\nPS > Get-AWSCmdletName -ApiOperation DescribeInstances\n```\n\n<table>\n<thead>\n<tr>\n<th>CmdletName</th>\n<th>ServiceOperation</th>\n<th>ServiceName</th>\n<th>CmdletNounPrefix</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>DescribeInstances</td>\n<td>DescribeInstances</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>EC2Instance</td>\n<td>DescribeInstances</td>\n<td>Amazon GameLift Service</td>\n<td>GML</td>\n</tr>\n<tr>\n<td>GMLInstance</td>\n<td>DescribeInstances</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nThe -ApiOperation parameter is the default parameter, so you can omit the parameter name. The following example is equivalent to the previous one:\n\n```\nPS > Get-AWSCmdletName DescribeInstances\n```\nIf you know the names of both the API and the service, you can include the -Service parameter along with either the cmdlet noun prefix or part of the AWS service name. For example, the cmdlet noun prefix for Amazon EC2 is EC2. To get the cmdlet name that corresponds to the DescribeInstances API in the Amazon EC2 service, run one of the following commands. They are all result in the same output:\n\n```\nPS > Get-AWSCmdletName -ApiOperation DescribeInstances -Service EC2\nPS > Get-AWSCmdletName -ApiOperation DescribeInstances -Service Compute\nPS > Get-AWSCmdletName -ApiOperation DescribeInstances -Service \"Compute Cloud\"\n```\n\n<table>\n<thead>\n<tr>\n<th>CmdletName</th>\n<th>ServiceOperation</th>\n<th>ServiceName</th>\n<th>CmdletNounPrefix</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Get-EC2Instance</td>\n<td>DescribeInstances</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n</tbody>\n</table>\n\nParameter values in these commands are case-insensitive.\n\nIf you do not know the name of either the desired AWS service API or the AWS service, you can use the -ApiOperation parameter, along with the pattern to match, and the -MatchWithRegex parameter. For example, to get all available cmdlet names that contain SecurityGroup, run the following command:\n\n```\nPS > Get-AWSCmdletName -ApiOperation SecurityGroup -MatchWithRegex\n```\n\n<table>\n<thead>\n<tr>\n<th>CmdletName</th>\n<th>ServiceOperation</th>\n<th>ServiceName</th>\n<th>CmdletNounPrefix</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Approve-ECCacheSecurityGroupIngress</td>\n<td>AuthorizeCacheSecurityGroupIngress</td>\n<td>Amazon ElastiCache</td>\n<td>EC</td>\n</tr>\n<tr>\n<td>Get-ECCacheSecurityGroup</td>\n<td>DescribeCacheSecurityGroups</td>\n<td>Amazon ElastiCache</td>\n<td>EC</td>\n</tr>\n<tr>\n<td>New-ECCacheSecurityGroup</td>\n<td>CreateCacheSecurityGroup</td>\n<td>Amazon ElastiCache</td>\n<td>EC</td>\n</tr>\n<tr>\n<td>Remove-ECCacheSecurityGroup</td>\n<td>DeleteCacheSecurityGroup</td>\n<td>Amazon ElastiCache</td>\n<td>EC</td>\n</tr>\n<tr>\n<td>Revoke-ECCacheSecurityGroupIngress</td>\n<td>RevokeCacheSecurityGroupIngress</td>\n<td>Amazon ElastiCache</td>\n<td>EC</td>\n</tr>\n<tr>\n<td>Add-EC2SecurityGroupToClientVpnTargetNetwrk</td>\n<td>ApplySecurityGroupsToClientVpnTargetNetwork</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Get-EC2SecurityGroup</td>\n<td>DescribeSecurityGroups</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Get-EC2SecurityGroupReference</td>\n<td>DescribeSecurityGroupReferences</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Grant-EC2SecurityGroupEgress</td>\n<td>AuthorizeSecurityGroupEgress</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Grant-EC2SecurityGroupIngress</td>\n<td>AuthorizeSecurityGroupIngress</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>New-EC2SecurityGroup</td>\n<td>CreateSecurityGroup</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Remove-EC2SecurityGroup</td>\n<td>DeleteSecurityGroup</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Revoke-EC2SecurityGroupEgress</td>\n<td>RevokeSecurityGroupEgress</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Revoke-EC2SecurityGroupIngress</td>\n<td>RevokeSecurityGroupIngress</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Update-EC2SecurityGroupRuleEgressDescription</td>\n<td>UpdateSecurityGroupRuleEgressDescription</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Update-EC2SecurityGroupRuleIngressDescription</td>\n<td>UpdateSecurityGroupRuleIngressDescription</td>\n<td>Amazon Elastic Compute Cloud</td>\n<td>EC2</td>\n</tr>\n<tr>\n<td>Edit-EFSMountTargetSecurityGroup</td>\n<td>ModifyMountTargetSecurityGroups</td>\n<td>Amazon Elastic File System</td>\n<td>EFS</td>\n</tr>\n<tr>\n<td>Get-EFSMountTargetSecurityGroup</td>\n<td>DescribeMountTargetSecurityGroups</td>\n<td>Amazon Elastic File System</td>\n<td>EFS</td>\n</tr>\n<tr>\n<td>CmdletName</td>\n<td>ServiceOperation</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>------------------------------------</td>\n<td>---------------------------</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Elastic Load Balancing</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Set-ELBSecurityGroup</td>\n<td>SetSecurityGroups</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Elastic Load Balancing V2</td>\n<td>ELB</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Enable-RDSDBSecurityGroupIngress</td>\n<td>AuthorizedDBSecurityGroupIngress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Relational Database Service RDS</td>\n<td>DescribeDBSecurityGroups</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>New-RDSDBSecurityGroup</td>\n<td>CreateDBSecurityGroup</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Relational Database Service RDS</td>\n<td>DeleteDBSecurityGroup</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Remove-RDSDBSecurityGroup</td>\n<td>RevokeDBSecurityGroupIngress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Relational Database Service RDS</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Approve-RSClusterSecurityGroupIngress</td>\n<td>AuthorizeClusterSecurityGroupIngress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Redshift</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Get-RSClusterSecurityGroup</td>\n<td>DescribeClusterSecurityGroups</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Redshift</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>New-RSClusterSecurityGroup</td>\n<td>CreateClusterSecurityGroup</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Redshift</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Remove-RSClusterSecurityGroup</td>\n<td>DeleteClusterSecurityGroup</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Redshift</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Revoke-RSClusterSecurityGroupIngress</td>\n<td>RevokeClusterSecurityGroupIngress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Redshift</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Update-EC2SecurityGroupRuleEgressDescription</td>\n<td>UpdateSecurityGroupRuleDescriptionsEgress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Add-EC2SecurityGroupToClientVpnTargetNetwork</td>\n<td>ApplySecurityGroupsToClientVpnTargetNetwork</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Get-EC2SecurityGroup</td>\n<td>DescribeSecurityGroups</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Get-EC2SecurityGroupReference</td>\n<td>DescribeSecurityGroupReferences</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Get-EC2StaleSecurityGroup</td>\n<td>DescribeStaleSecurityGroups</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Grant-EC2SecurityGroupEgress</td>\n<td>AuthorizeSecurityGroupEgress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Grant-EC2SecurityGroupIngress</td>\n<td>AuthorizeSecurityGroupIngress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>New-EC2SecurityGroup</td>\n<td>CreateSecurityGroup</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Remove-EC2SecurityGroup</td>\n<td>DeleteSecurityGroup</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Revoke-EC2SecurityGroupEgress</td>\n<td>RevokeSecurityGroupEgress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Revoke-EC2SecurityGroupIngress</td>\n<td>RevokeSecurityGroupIngress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Update-EC2SecurityGroupRuleEgressDescription</td>\n<td>UpdateSecurityGroupRuleDescriptionsIngress</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nIf you know the name of the AWS service but not the AWS service API, include both the `-MatchWithRegex` parameter and the `-Service` parameter to scope the search down to a single service. For example, to get all cmdlet names that contain `SecurityGroup` in only the Amazon EC2 service, run the following command:\n\n```\nPS > Get-AWSCmdletName -ApiOperation SecurityGroup -MatchWithRegex -Service EC2\n```\n\n<table>\n<thead>\n<tr>\n<th>CmdletName</th>\n<th>ServiceOperation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n</tr>\n<tr>\n<td>Add-EC2SecurityGroupToClientVpnTargetNetwork</td>\n<td>ApplySecurityGroupsToClientVpnTargetNetwork</td>\n</tr>\n<tr>\n<td>Get-EC2SecurityGroup</td>\n<td>DescribeSecurityGroups</td>\n</tr>\n<tr>\n<td>Get-EC2SecurityGroupReference</td>\n<td>DescribeSecurityGroupReferences</td>\n</tr>\n<tr>\n<td>Get-EC2StaleSecurityGroup</td>\n<td>DescribeStaleSecurityGroups</td>\n</tr>\n<tr>\n<td>Grant-EC2SecurityGroupEgress</td>\n<td>AuthorizeSecurityGroupEgress</td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n</tr>\n<tr>\n<td>Grant-EC2SecurityGroupIngress</td>\n<td>AuthorizeSecurityGroupIngress</td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n</tr>\n<tr>\n<td>New-EC2SecurityGroup</td>\n<td>CreateSecurityGroup</td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n</tr>\n<tr>\n<td>Remove-EC2SecurityGroup</td>\n<td>DeleteSecurityGroup</td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n</tr>\n<tr>\n<td>Revoke-EC2SecurityGroupEgress</td>\n<td>RevokeSecurityGroupEgress</td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n</tr>\n<tr>\n<td>Revoke-EC2SecurityGroupIngress</td>\n<td>RevokeSecurityGroupIngress</td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n</tr>\n<tr>\n<td>Update-EC2SecurityGroupRuleEgressDescription</td>\n<td>UpdateSecurityGroupRuleDescriptionsEgress</td>\n</tr>\n<tr>\n<td>Amazon Elastic Compute Cloud EC2</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nIf you know the name of the AWS Command Line Interface (AWS CLI) command, you can use the `-AwsCliCommand` parameter and the desired AWS CLI command name to get the name of the cmdlet.\nthat's based on the same API. For example, to get the cmdlet name that corresponds to the authorize-security-group-ingress AWS CLI command call in the Amazon EC2 service, run the following command:\n\n```powershell\nPS > Get-AWSCmdletName -AwsCliCommand \"aws ec2 authorize-security-group-ingress\"\n```\n\n<table>\n<thead>\n<tr>\n<th>CmdletName</th>\n<th>ServiceOperation</th>\n<th>ServiceName</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Grant-EC2SecurityGroupIngress</td>\n<td>AuthorizeSecurityGroupIngress</td>\n<td>Amazon Elastic Compute Cloud EC2</td>\n</tr>\n</tbody>\n</table>\n\nThe Get-AWSCmdletName cmdlet needs only enough of the AWS CLI command name to identify the service and the AWS API.\n\nTo get a list of all of the cmdlets in the Tools for PowerShell Core, run the PowerShell Get-Command cmdlet, as shown in the following example.\n\n```powershell\nPS > Get-Command -Module AWSPowerShell.NetCore\n```\n\nYou can run the same command with -Module AWSPowerShell to see the cmdlets in the AWS Tools for Windows PowerShell.\n\nThe Get-Command cmdlet generates the list of cmdlets in alphabetical order. Note that by default the list is sorted by PowerShell verb, rather than PowerShell noun.\n\nTo sort results by service instead, run the following command:\n\n```powershell\nPS > Get-Command -Module AWSPowerShell.NetCore | Sort-Object Noun,Verb\n```\n\nTo filter the cmdlets that are returned by the Get-Command cmdlet, pipe the output to the PowerShell Select-String cmdlet. For example, to view the set of cmdlets that work with AWS regions, run the following command:\n\n```powershell\nPS > Get-Command -Module AWSPowerShell.NetCore | Select-String region\n```\n\nYou can also find cmdlets for a specific service by filtering for the service prefix of cmdlet nouns. To see the list of available service prefixes, run Get-AWSPowerShellVersion -ListServiceVersionInfo. The following example returns cmdlets that support the Amazon CloudWatch Events service.\n\n```powershell\nPS > Get-Command -Module AWSPowerShell.NetCore -Noun CWE*\n```\n\n<table>\n<thead>\n<tr>\n<th>CommandType</th>\n<th>Name</th>\n<th>Version</th>\n<th>Source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Cmdlet</td>\n<td>Add-CWEResourceTag</td>\n<td>3.3.563.1</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>AWSPowerShell.NetCore</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Cmdlet</td>\n<td>Disable-CWEEventSource</td>\n<td>3.3.563.1</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>AWSPowerShell.NetCore</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Cmdlet</td>\n<td>Disable-CWERule</td>\n<td>3.3.563.1</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>AWSPowerShell.NetCore</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n## Cmdlet Naming and Aliases\n\nThe cmdlets in the AWS Tools for PowerShell for each service are based on the methods provided by the AWS SDK for the service. However, because of PowerShell's mandatory naming conventions, the name of a cmdlet might be different from the name of the API call or method on which it is based. For example, the `Get-EC2Instance` cmdlet is based on the Amazon EC2DescribeInstances method.\nIn some cases, the cmdlet name may be similar to a method name, but it may actually perform a different function. For example, the Amazon S3 `GetObject` method retrieves an Amazon S3 object. However, the `Get-S3Object` cmdlet returns information about an Amazon S3 object rather than the object itself.\n\n```powershell\nPS > Get-S3Object -BucketName text-content -Key aws-tech-docs\nETag : \"df000002a0fe0000f3c000004EXAMPLE\"\nBucketName : aws-tech-docs\nKey : javascript/frameset.js\nLastModified : 6/15/2011 1:24:18 PM\nOwner : Amazon.S3.Model.Owner\nSize : 512\nStorageClass : STANDARD\n```\n\nTo get an S3 object with the AWS Tools for PowerShell, run the `Read-S3Object` cmdlet:\n\n```powershell\nPS > Read-S3Object -BucketName text-content -Key text-object.txt -file c:\\tmp\\text-object-download.text\nMode LastWriteTime Length Name\n---- ------------- ------ ----\n-a--- 11/5/2012 7:29 PM 20622 text-object-download.text\n```\n\n**Note**\n\nThe cmdlet help for an AWS cmdlet provides the name of the AWS SDK API on which the cmdlet is based. For more information about standard PowerShell verbs and their meanings, see [Approved Verbs for PowerShell Commands](#).\n\nAll AWS cmdlets that use the Remove verb – and the `Stop-EC2Instance` cmdlet when you add the `-Terminate` parameter – prompt for confirmation before proceeding. To bypass confirmation, add the `-Force` parameter to your command.\n\n**Important**\n\nAWS cmdlets do not support the `-WhatIf` switch.\n\n**Aliases**\n\nSetup of the AWS Tools for PowerShell installs an aliases file that contains aliases for many of the AWS cmdlets. You might find these aliases to be more intuitive than the cmdlet names. For example, service names and AWS SDK method names replace PowerShell verbs and nouns in some aliases. An example is the `EC2-DescribeInstances` alias.\n\nOther aliases use verbs that, though they do not follow standard PowerShell conventions, can be more descriptive of the actual operation. For example, the alias file maps the alias `Get-S3Content` to the cmdlet `Read-S3Object`.\n\n```powershell\nPS > Set-Alias -Name Get-S3Content -Value Read-S3Object\n```\n\nThe aliases file is located in the AWS Tools for PowerShell installation directory. To load the aliases into your environment, `dot-source` the file. The following is a Windows-based example.\n\n```powershell\nPS > . \"C:\\Program Files (x86)\\AWS Tools\\PowerShell\\AWSPowershell\\AWSAliases.ps1\"\n```\n\nFor a Linux or macOS shell, it might look like this:\nTo show all AWS Tools for PowerShell aliases, run the following command. This command uses the `?` alias for the PowerShell `Where-Object` cmdlet and the `Source` property to filter for only aliases that come from the `AWSPowerShell.NetCore` module.\n\n```\nPS > Get-Alias | ? Source -like \"AWSPowerShell.NetCore\"\n```\n\n<table>\n<thead>\n<tr>\n<th>CommandType</th>\n<th>Name</th>\n<th>Version</th>\n<th>Source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Alias</td>\n<td>Add-ASInstances</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Add-CTTag</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Add-DPTags</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Add-DSIpRoutes</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Add-ELBTags</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Add-EMRTag</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Add-ESTag</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Add-MLTag</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Clear-AWSCredentials</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Clear-AWSDefaults</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Dismount-ASInstances</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Edit-EC2Hosts</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Edit-RSClusterIAMRoles</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Enable-ORGAllFeatures</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Find-CTEvents</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASACases</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASAccountLimits</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASCommunications</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASAServices</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASSeverityLevels</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASATrustedAdvisorCheckRefreshStatuses</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASATrustedAdvisorChecks</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASATrustedAdvisorCheckSummaries</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASLifecycleHooks</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-ASLifecycleHookTypes</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-AWSCredentials</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-CDApplications</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-CDDeployments</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-CFCloudFrontOriginAccessIdentities</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-CFDistributions</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-CFGConfigRules</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-CFGConfigurationRecorders</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-CFGDeliveryChannels</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-CFInvalidations</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n<tr>\n<td>Alias</td>\n<td>Get-CFNStackEvents</td>\n<td>3.3.343.0</td>\n<td>AWSPowerShell</td>\n</tr>\n</tbody>\n</table>\n\nTo add your own aliases to this file, you might need to raise the value of PowerShell's `$MaximumAliasCount` preference variable to a value greater than 5500. The default value is 4096; you can raise it to a maximum of 32768. To do this, run the following.\n\n```\nPS > $MaximumAliasCount = 32768\n```\n\nTo verify that your change was successful, enter the variable name to show its current value.\n\n```\nPS > $MaximumAliasCount\n32768\n```\nPipelining and $AWSHistory\n\nFor AWS service calls that return collections, the objects within the collection are enumerated to the pipeline. Result objects that contain additional fields beyond the collection and which are not paging control fields have these fields added as Note properties for the calls. These Note properties are logged in the new $AWSHistory session variable, should you need to access this data. The $AWSHistory variable is described in the next section.\n\nNote\nIn versions of the Tools for Windows PowerShell prior to v1.1, the collection object itself was emitted, which required the use of foreach {$_-getenumerator()} to continue pipelining.\n\nExamples\n\nThe following example returns a list of AWS Regions and your Amazon EC2 machine images (AMIs) in each Region.\n\n```powershell\nPS > Get-AWSRegion | % { Echo $_.Name; Get-EC2Image -Owner self -Region $_ }\n```\n\nThe following example stops all Amazon EC2 instances in the current default region.\n\n```powershell\nPS > Get-EC2Instance | Stop-EC2Instance\n```\n\nBecause collections enumerate to the pipeline, the output from a given cmdlet might be $null, a single object, or a collection. If it is a collection, you can use the `.Count` property to determine the size of the collection. However, the `.Count` property is not present when only a single object is emitted. If your script needs to determine, in a consistent way, how many objects were emitted, you can check the `EmittedObjectsCount` property of the last command value in $AWSHistory.\n\n$AWSHistory\n\nTo better support pipelining, output from AWS cmdlets is not reshaped to include the service response and result instances as Note properties on the emitted collection object. Instead, for those calls that emit a single collection as output, the collection is now enumerated to the PowerShell pipeline. This means that the AWS SDK response and result data cannot exist in the pipe, because there is no containing collection object to which it can be attached.\n\nAlthough most users probably won't need this data, it can be useful for diagnostic purposes, because you can see exactly what was sent to and received from the underlying AWS service calls made by the cmdlet.\n\nStarting with version 1.1, this data and more is now available in a new shell variable named $AWSHistory. This variable maintains a record of AWS cmdlet invocations and the service responses that were received for each invocation. Optionally, this history can be configured to also record the service requests that each cmdlet made. Additional useful data, such as the overall execution time of the cmdlet, can also be obtained from each entry. For security reasons, requests and responses that contain sensitive data aren't recorded by default. However, the history can be configured to override this behavior if needed. For more information, see the Set-AWSHistoryConfiguration cmdlet shown below.\n\nEach entry in the $AWSHistory.Commands list is of type AWSCmdletHistory. This type has the following useful members:\n\n**CmdletName**\n\nName of the cmdlet.\n\n**CmdletStart**\n\nDateTime that the cmdlet was run.\n$AWSHistory\n\n**CmdletEnd**\n\nDateTime that the cmdlet finished all processing.\n\n**Requests**\n\nIf request recording is enabled, list of last service requests.\n\n**Responses**\n\nList of last service responses received.\n\n**LastServiceResponse**\n\nHelper to return the most recent service response.\n\n**LastServiceRequest**\n\nHelper to return the most recent service request, if available.\n\nNote that the $AWSHistory variable is not created until an AWS cmdlet making a service call is used. It evaluates to $null until that time.\n\n**Note**\n\nEarlier versions of the Tools for Windows PowerShell emitted data related to service responses as Note properties on the returned object. These are now found on the response entries that are recorded for each invocation in the list.\n\n### Set-AWSHistoryConfiguration\n\nA cmdlet invocation can hold zero or more service request and response entries. To limit memory impact, the $AWSHistory list keeps a record of only the last five cmdlet executions by default; and for each, the last five service responses (and if enabled, last five service requests). You can change these default limits by running the Set-AWSHistoryConfiguration cmdlet. It allows you to both control the size of the list, and whether service requests are also logged:\n\n```\nPS > Set-AWSHistoryConfiguration -MaxCmdletHistory <value> -MaxServiceCallHistory <value> -RecordServiceRequests -IncludeSensitiveData\n```\n\nAll parameters are optional.\n\nThe MaxCmdletHistory parameter sets the maximum number of cmdlets that can be tracked at any time. A value of 0 turns off recording of AWS cmdlet activity. The MaxServiceCallHistory parameter sets the maximum number of service responses (and/or requests) that are tracked for each cmdlet. The RecordServiceRequests parameter, if specified, turns on tracking of service requests for each cmdlet. The IncludeSensitiveData parameter, if specified, turns on tracking of service responses and requests (if tracked) that contain sensitive data for each cmdlet.\n\nIf run with no parameters, Set-AWSHistoryConfiguration simply turns off any prior request recording, leaving the current list sizes unchanged.\n\nTo clear all entries in the current history list, run the Clear-AWSHistory cmdlet.\n\n### $AWSHistory Examples\n\nEnumerate the details of the AWS cmdlets that are being held in the list to the pipeline.\n\n```\nPS > $AWSHistory.Commands\n```\n\nAccess the details of the last AWS cmdlet that was run:\nAccess the details of the last service response received by the last AWS cmdlet that was run. If an AWS cmdlet is paging output, it may make multiple service calls to obtain either all data or the maximum amount of data (determined by parameters on the cmdlet).\n\nAccess the details of the last request made (again, a cmdlet may make more than one request if it is paging on the user's behalf). Yields $null unless service request tracing is enabled.\n\nAutomatic Page-to-Completion for Operations that Return Multiple Pages\n\nFor service APIs that impose a default maximum object return count for a given call or that support pageable result sets, all cmdlets \"page-to-completion\" by default. Each cmdlet makes as many calls as necessary on your behalf to return the complete data set to the pipeline.\n\nIn the following example, which uses Get-S3Object, the $c variable contains S3Object instances for every key in the bucket test, potentially a very large data set.\n\nIf you want to retain control of the amount of data returned, you can use parameters on the individual cmdlets (for example, MaxKey on Get-S3Object) or you can explicitly handle paging yourself by using a combination of paging parameters on the cmdlets, and data placed in the $AWSHistory variable to get the service's next token data. The following example uses the MaxKeys parameter to limit the number of S3Object instances returned to no more than the first 500 found in the bucket.\n\nTo know if more data was available but not returned, use the $AWSHistory session variable entry that recorded the service calls made by the cmdlet.\n\nIf the following expression evaluates to $true, you can find the next marker for the next set of results using $AWSHistory.LastServiceResponse.NextMarker:\n\nTo manually control paging with Get-S3Object, use a combination of the MaxKey and Marker parameters for the cmdlet and the IsTruncated/NextMarker notes on the last recorded response. In the following example, the variable $c contains up to a maximum of 500 S3Object instances for the next 500 objects that are found in the bucket after the start of the specified key prefix marker.\nConfiguring Federated Identity with the AWS Tools for PowerShell\n\nTo let users in your organization access AWS resources, you must configure a standard and repeatable authentication method for purposes of security, auditability, compliance, and the capability to support role and account separation. Although it's common to provide users with the ability to access AWS APIs, without federated API access, you would also have to create AWS Identity and Access Management (IAM) users, which defeats the purpose of using federation. This topic describes SAML (Security Assertion Markup Language) support in the AWS Tools for PowerShell that eases your federated access solution.\n\nSAML support in the AWS Tools for PowerShell lets you provide your users federated access to AWS services. SAML is an XML-based, open-standard format for transmitting user authentication and authorization data between services; in particular, between an identity provider (such as Active Directory Federation Services), and a service provider (such as AWS). For more information about SAML and how it works, see SAML on Wikipedia, or SAML Technical Specifications at the Organization for the Advancement of Structured Information Standards (OASIS) website. SAML support in the AWS Tools for PowerShell is compatible with SAML 2.0.\n\nPrerequisites\n\nYou must have the following in place before you try to use SAML support for the first time.\n\n- A federated identity solution that is correctly integrated with your AWS account for console access by using only your organizational credentials. For more information about how to do this specifically for Active Directory Federation Services, see About SAML 2.0 Federation in the IAM User Guide, and the blog post, Enabling Federation to AWS Using Windows Active Directory, AD FS, and SAML 2.0. Although the blog post covers AD FS 2.0, the steps are similar if you are running AD FS 3.0.\n- Version 3.1.31.0 or newer of the AWS Tools for PowerShell installed on your local workstation.\n\nHow an Identity-Federated User Gets Federated Access to AWS Service APIs\n\nThe following process describes, at a high level, how an Active Directory (AD) user is federated by AD FS to gain access to AWS resources.\n1. The client on federated user's computer authenticates against AD FS.\n2. If authentication succeeds, AD FS sends the user a SAML assertion.\n3. The user's client sends the SAML assertion to the AWS Security Token Service (STS) as part of a SAML federation request.\n4. STS returns a SAML response that contains AWS temporary credentials for a role the user can assume.\n5. The user accesses AWS service APIs by including those temporary credentials in request made by AWS Tools for PowerShell.\n\nHow SAML Support Works in the AWS Tools for PowerShell\n\nThis section describes how AWS Tools for PowerShell cmdlets enable configuration of SAML-based identity federation for users.\n1. AWS Tools for PowerShell authenticates against AD FS by using the Windows user's current credentials, or interactively, when the user tries to run a cmdlet that requires credentials to call into AWS.\n\n2. AD FS authenticates the user.\n\n3. AD FS generates a SAML 2.0 authentication response that includes an assertion; the purpose of the assertion is to identify and provide information about the user. AWS Tools for PowerShell extracts the list of the user's authorized roles from the SAML assertion.\n\n4. AWS Tools for PowerShell forwards the SAML request, including the requested role's Amazon Resource Names (ARN), to STS by making the AssumeRoleWithSAMLRequest API call.\n\n5. If the SAML request is valid, STS returns a response that contains the AWS AccessKeyId, SecretAccessKey, and SessionToken. These credentials last for 3,600 seconds (1 hour).\n\n6. The user now has valid credentials to work with any AWS service APIs that the user's role is authorized to access. AWS Tools for PowerShell automatically applies these credentials for any subsequent AWS API calls, and renews them automatically when they expire.\n\n **Note**\n When the credentials expire, and new credentials are required, AWS Tools for PowerShell automatically reauthenticates with AD FS, and obtains new credentials for a subsequent hour. For users of domain-joined accounts, this process occurs silently. For accounts that are not domain-joined, AWS Tools for PowerShell prompts users to enter their credentials before they can reauthenticate.\n\n---\n\n### How to Use the PowerShell SAML Configuration Cmdlets\n\nAWS Tools for PowerShell includes two new cmdlets that provide SAML support:\n\n- **Set-AWSSam1Endpoint** configures your AD FS endpoint, assigns a friendly name to the endpoint, and optionally describes the authentication type of the endpoint.\n\n- **Set-AWSSam1RoleProfile** creates or edits a user account profile that you want to associate with an AD FS endpoint, identified by specifying the friendly name you provided to the Set-\nAWSSamlEndpoint cmdlet. Each role profile maps to a single role that a user is authorized to perform.\n\nJust as with AWS credential profiles, you assign a friendly name to the role profile. You can use the same friendly name with the Set-AWSCredential cmdlet, or as the value of the -ProfileName parameter for any cmdlet that invokes AWS service APIs.\n\nOpen a new AWS Tools for PowerShell session. If you are running PowerShell 3.0 or newer, the AWS Tools for PowerShell module is automatically imported when you run any of its cmdlets. If you are running PowerShell 2.0, you must import the module manually by running the `Import-Module` cmdlet, as shown in the following example.\n\n```\nPS > Import-Module \"C:\\Program Files (x86)\\AWS Tools\\PowerShell\\AWSPowerShell\\AWSPowerShell.psd1\"\n```\n\n**How to Run the Set-AWSSamlEndpoint and Set-AWSSamlRoleProfile Cmdlets**\n\n1. First, configure the endpoint settings for the AD FS system. The simplest way to do this is to store the endpoint in a variable, as shown in this step. Be sure to replace the placeholder account IDs and AD FS host name with your own account IDs and AD FS host name. Specify the AD FS host name in the Endpoint parameter.\n\n```\nPS > $endpoint = \"https://adfs.example.com/adfs/ls/IdpInitiatedSignOn.aspx?\nloginToRp=urn:amazon:webservices\"\n```\n\n2. To create the endpoint settings, run the Set-AWSSamlEndpoint cmdlet, specifying the correct value for the AuthenticationType parameter. Valid values include Basic, Digest, Kerberos, Negotiate, and NTLM. If you do not specify this parameter, the default value is Kerberos.\n\n```\nPS > $epName = Set-AWSSamlEndpoint -Endpoint $endpoint -StoreAs ADFS-Demo -\nAuthenticationType NTLM\n```\n\nThe cmdlet returns the friendly name you assigned by using the -StoreAs parameter, so you can use it when you run Set-AWSSamlRoleProfile in the next line.\n\n3. Now, run the Set-AWSSamlRoleProfile cmdlet to authenticate with the AD FS identity provider and get the set of roles (in the SAML assertion) that the user is authorized to perform.\n\nThe Set-AWSSamlRoleProfile cmdlet uses the returned set of roles to either prompt the user to select a role to associate with the specified profile, or validate that role data provided in parameters is present (if not, the user is prompted to choose). If the user is authorized for only one role, the cmdlet associates the role with the profile automatically, without prompting the user. There is no need to provide a credential to set up a profile for domain-joined usage.\n\n```\nPS > Set-AWSSamlRoleProfile -StoreAs SAMLDemoProfile -EndpointName $epName\n```\n\nAlternatively, for non-domain-joined accounts, you can provide Active Directory credentials, and then select an AWS role to which the user has access, as shown in the following line. This is useful if you have different Active Directory user accounts to differentiate roles within your organization (for example, administration functions).\n\n```\nPS > $credential = Get-Credential -Message \"Enter the domain credentials for the endpoint\"\n```\n4. In either case, the `Set-AWSSamlRoleProfile` cmdlet prompts you to choose which role should be stored in the profile. The following example shows two available roles: ADFS-Dev, and ADFS-Production. The IAM roles are associated with your AD login credentials by the AD FS administrator.\n\nAlternatively, you can specify a role without the prompt, by entering the `RoleARN`, `PrincipalARN`, and optional `NetworkCredential` parameters. If the specified role is not listed in the assertion returned by authentication, the user is prompted to choose from available roles.\n\n5. You can create profiles for all roles in a single command by adding the `StoreAllRoles` parameter, as shown in the following code. Note that the role name is used as the profile name.\n\n---\n\n## How to Use Role Profiles to Run Cmdlets that Require AWS Credentials\n\nTo run cmdlets that require AWS credentials, you can use role profiles defined in the AWS shared credential file. Provide the name of a role profile to `Set-AWSCredential` (or as the value for any `ProfileName` parameter in the AWS Tools for PowerShell) to get temporary AWS credentials automatically for the role that is described in the profile.\n\nAlthough you use only one role profile at a time, you can switch between profiles within a shell session. The `Set-AWSCredential` cmdlet does not authenticate and get credentials when you run it by itself; the cmdlet records that you want to use a specified role profile. Until you run a cmdlet that requires AWS credentials, no authentication or request for credentials occurs.\n\nYou can now use the temporary AWS credentials that you obtained with the SAMLDemoProfile profile to work with AWS service APIs. The following sections show examples of how to use role profiles.\n\n### Example 1: Set a Default Role with `Set-AWSCredential`\n\nThis example sets a default role for a AWS Tools for PowerShell session by using `Set-AWSCredential`. Then, you can run cmdlets that require credentials, and are authorized by the specified role. This example lists all Amazon Elastic Compute Cloud instances in the US West (Oregon) Region that are associated with the profile you specified with the `Set-AWSCredential` cmdlet.\nExample 2: Change Role Profiles During a PowerShell Session\n\nThis example lists all available Amazon S3 buckets in the AWS account of the role associated with the SAMLDemoProfile profile. The example shows that although you might have been using another profile earlier in your AWS Tools for PowerShell session, you can change profiles by specifying a different value for the -ProfileName parameter with cmdlets that support it. This is a common task for administrators who manage Amazon S3 from the PowerShell command line.\n\n```\nPS > Get-S3Bucket -ProfileName SAMLDemoProfile\n\nCreationDate BucketName\n------------ ----------\n7/25/2013 3:16:56 AM mybucket1\n4/15/2015 12:46:50 AM mybucket2\n4/15/2015 6:15:53 AM mybucket3\n1/12/2015 11:20:16 PM mybucket4\n```\n\nNote that the Get-S3Bucket cmdlet specifies the name of the profile created by running the Set-AWSSamlRoleProfile cmdlet. This command could be useful if you had set a role profile earlier in your session (for example, by running the Set-AWSCredential cmdlet) and wanted to use a different role profile for the Get-S3Bucket cmdlet. The profile manager makes temporary credentials available to the Get-S3Bucket cmdlet. Although the credentials expire after 1 hour (a limit enforced by STS), AWS Tools for PowerShell automatically refreshes the credentials by requesting a new SAML assertion when the tool detects that the current credentials have expired.\n\nFor domain-joined users, this process occurs without interruption, because the current user's Windows identity is used during authentication. For non-domain-joined user accounts, AWS Tools for PowerShell shows a PowerShell credential prompt requesting the user password. The user provides credentials that are used to reauthenticate the user and get a new assertion.\n\nExample 3: Get Instances in a Region\n\nThe following example lists all Amazon EC2 instances in the Asia Pacific (Sydney) Region that are associated with the account used by the ADFS-Production profile. This is a useful command for returning all Amazon EC2 instances in a region.\n\n```\nPS > (Get-Ec2Instance -ProfileName ADFS-Production -Region ap-southeast-2).Instances | Select InstanceType, @{Name=\"Servername\";Expression={$_.tags | where key -eq \"Name\" | Select Value -Expand Value}}\n\nInstanceType Servername\n------------- ----------\nt2.small DC2\n t1.micro NAT1\n t1.micro RDGW1\n t1.micro RDGW2\n t1.micro NAT2\n t2.small DC1\n t2.micro BUILD\n```\nAdditional Reading\n\nFor general information about how to implement federated API access, see [How to Implement a General Solution for Federated API/CLI Access Using SAML 2.0](#).\n\nFor support questions or comments, visit the AWS Developer Forums for [PowerShell Scripting](#) or [.NET Development](#).\nUsing the AWS Tools for PowerShell\n\nThis section provides examples of using the AWS Tools for PowerShell to access AWS services. These examples help demonstrate how to use the cmdlets to perform actual AWS tasks.\n\nPowerShell File Concatenation Encoding\n\nSome cmdlets in the AWS Tools for PowerShell edit existing files or records that you have in AWS. An example is `Edit-R53ResourceRecordSet`, which calls the `ChangeResourceRecordSets` API for Amazon Route 53.\n\nWhen you edit or concatenate files in PowerShell 5.1 or older releases, PowerShell encodes the output in UTF-16, not UTF-8. This can add unwanted characters and create results that are not valid. A hexadecimal editor can reveal the unwanted characters.\n\nTo avoid converting file output to UTF-16, you can pipe your command into PowerShell's `Out-File` cmdlet and specify UTF-8 encoding, as shown in the following example:\n\n```\nPS > *some file concatenation command* | Out-File filename.txt -Encoding utf8\n```\n\nIf you are running AWS CLI commands from within the PowerShell console, the same behavior applies. You can pipe the output of an AWS CLI command into `Out-File` in the PowerShell console. Other cmdlets, such as `Export-Csv` or `Export-Clixml`, also have an `Encoding` parameter. For a complete list of cmdlets that have an `Encoding` parameter, and that allow you to correct the encoding of the output of a concatenated file, run the following command:\n\n```\nPS > Get-Command -ParameterName \"Encoding\"\n```\n\n**Note**\n\nPowerShell 6.0 and newer, including PowerShell Core, automatically retains UTF-8 encoding for concatenated file output.\n\nReturned Objects for the PowerShell Tools\n\nTo make AWS Tools for PowerShell more useful in a native PowerShell environment, the object returned by a AWS Tools for PowerShell cmdlet is a .NET object, not the JSON text object that is typically returned from the corresponding API in the AWS SDK. For example, `Get-S3Bucket` emits a `Buckets` collection, not an Amazon S3 JSON response object. The `Buckets` collection can be placed in the PowerShell pipeline and interacted with in appropriate ways. Similarly, `Get-EC2Instance` emits a `Reservation` .NET object collection, not a `DescribeEC2Instances` JSON result object. This behavior is by design and enables the AWS Tools for PowerShell experience to be more consistent with idiomatic PowerShell.\n\nThe actual service responses are available for you if you need them. They are stored as `note` properties on the returned objects. For API actions that support paging by using `NextToken` fields, these are also attached as `note` properties.\nAmazon EC2 (p. 60)\n\nThis section walks through the steps required to launch an Amazon EC2 instance including how to:\n\n- Retrieve a list of Amazon Machine Images (AMIs).\n- Create a key pair for SSH authentication.\n- Create and configure an Amazon EC2 security group.\n- Launch the instance and retrieve information about it.\n\nAmazon S3 (p. 53)\n\nThe section walks through the steps required to create a static website hosted in Amazon S3. It demonstrates how to:\n\n- Create and delete Amazon S3 buckets.\n- Upload files to an Amazon S3 bucket as objects.\n- Delete objects from an Amazon S3 bucket.\n- Designate an Amazon S3 bucket as a website.\n\nIAM and AWS Tools for PowerShell (p. 58)\n\nThis section demonstrates basic operations in AWS Identity and Access Management (IAM) including how to:\n\n- Create an IAM group.\n- Create an IAM user.\n- Add an IAM user to an IAM group.\n- Specify a policy for an IAM user.\n- Set a password and credentials for an IAM user.\n\nAWS Lambda and AWS Tools for PowerShell (p. 70)\n\nThis section provides a brief overview of the AWS Lambda Tools for PowerShell module and describes the required steps for setting up the module.\n\nAmazon SNS and Amazon SQS (p. 71)\n\nThis section walks through the steps required to subscribe an Amazon SQS queue to an Amazon SNS topic. It demonstrates how to:\n\n- Create an Amazon SNS topic.\n- Create an Amazon SQS queue.\n- Subscribe the queue to the topic.\n- Send a message to the topic.\n• Receive the message from the queue.\n\nCloudWatch (p. 74)\n\nThis section provides an example of how to publish custom data to CloudWatch.\n\n• Publish a Custom Metric to Your CloudWatch Dashboard.\n\nSee Also\n\n• Getting Started with the AWS Tools for Windows PowerShell (p. 24)\n\nTopics\n\n• Amazon S3 and Tools for Windows PowerShell (p. 53)\n• IAM and Tools for PowerShell (p. 58)\n• Amazon EC2 and Tools for Windows PowerShell (p. 60)\n• AWS Lambda and AWS Tools for PowerShell (p. 70)\n• Amazon SQS, Amazon SNS and Tools for Windows PowerShell (p. 71)\n• CloudWatch from the AWS Tools for Windows PowerShell (p. 74)\n• Using the ClientConfig parameter in cmdlets (p. 75)\n\nAmazon S3 and Tools for Windows PowerShell\n\nIn this section, we create a static website using the AWS Tools for Windows PowerShell using Amazon S3 and CloudFront. In the process, we demonstrate a number of common tasks with these services. This walkthrough is modeled after the Getting Started Guide for Host a Static Website, which describes a similar process using the AWS Management Console.\n\nThe commands shown here assume that you have set default credentials and a default region for your PowerShell session. Therefore, credentials and regions are not included in the invocation of the cmdlets.\n\nNote\nThere is currently no Amazon S3 API for renaming a bucket or object, and therefore, no single Tools for Windows PowerShell cmdlet for performing this task. To rename an object in S3, we recommend that you copy the object to one with a new name, by running the Copy-S3Object cmdlet, and then delete the original object by running the Remove-S3Object cmdlet.\n\nSee also\n\n• Using the AWS Tools for PowerShell (p. 51)\n• Hosting a Static Website on Amazon S3\n• Amazon S3 Console\n\nTopics\n\n• Create an Amazon S3 Bucket, Verify Its Region, and Optionally Remove It (p. 54)\n• Configure an Amazon S3 Bucket as a Website and Enable Logging (p. 54)\nCreate an Amazon S3 Bucket, Verify Its Region, and Optionally Remove It\n\nUse the `New-S3Bucket` cmdlet to create a new Amazon S3 bucket. The following examples creates a bucket named `website-example`. The name of the bucket must be unique across all regions. The example creates the bucket in the `us-west-1` region.\n\n```\nPS > New-S3Bucket -BucketName website-example -Region us-west-2\n```\n\n<table>\n<thead>\n<tr>\n<th>CreationDate</th>\n<th>BucketName</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>8/16/19 8:45:38 PM</td>\n<td>website-example</td>\n</tr>\n</tbody>\n</table>\n\nYou can verify the region in which the bucket is located using the `Get-S3BucketLocation` cmdlet.\n\n```\nPS > Get-S3BucketLocation -BucketName website-example\n```\n\n<table>\n<thead>\n<tr>\n<th>Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>us-west-2</td>\n</tr>\n</tbody>\n</table>\n\nWhen you're done with this tutorial, you can use the following line to remove this bucket. We suggest that you leave this bucket in place as we use it in subsequent examples.\n\n```\nPS > Remove-S3Bucket -BucketName website-example\n```\n\nNote that the bucket removal process can take some time to finish. If you try to re-create a same-named bucket immediately, the `New-S3Bucket` cmdlet can fail until the old one is completely gone.\n\nSee Also\n\n- [Using the AWS Tools for PowerShell](#)\n- [Put Bucket (Amazon S3 Service Reference)](#)\n- [AWS PowerShell Regions for Amazon S3](#)\n\nConfigure an Amazon S3 Bucket as a Website and Enable Logging\n\nUse the `Write-S3BucketWebsite` cmdlet to configure an Amazon S3 bucket as a static website. The following example specifies a name of `index.html` for the default content web page and a name of `error.html` for the default error web page. Note that this cmdlet does not create those pages. They need to be uploaded as Amazon S3 objects.\n\n```\nPS > Write-S3BucketWebsite -BucketName website-example -WebsiteConfiguration_IndexDocumentSuffix index.html -WebsiteConfiguration_ErrorDocumentSuffix error.html\n```\nUpload Objects to an Amazon S3 Bucket\n\nUse the `Write-S3Object` cmdlet to upload files from your local file system to an Amazon S3 bucket as objects. The example below creates and uploads two simple HTML files to an Amazon S3 bucket, and verifies the existence of the uploaded objects. The `-File` parameter to `Write-S3Object` specifies the name of the file in the local file system. The `-Key` parameter specifies the name that the corresponding object will have in Amazon S3.\n\nAmazon infers the content-type of the objects from the file extensions, in this case, \".html\".\n\n```powershell\n# Create the two files using here-strings and the Set-Content cmdlet\n$index_html = @\"<html><body><p>Hello, World!</p></body></html>\"\n$index_html | Set-Content index.html\n\n$error_html = @\"<html><body><p>This is an error page.</p></body></html>\"\n$error_html | Set-Content error.html\n\n# Upload the files to Amazon S3 using a foreach loop\nforeach ($f in \"index.html\", \"error.html\") {\n Write-S3Object -BucketName website-example -File $f -Key $f -CannedACLName public-read\n}\n\n# Verify that the files were uploaded\nGet-S3BucketWebsite -BucketName website-example\n```\n\n### Canned ACL Options\n\n<table>\n<thead>\n<tr>\n<th>IndexDocumentSuffix</th>\n<th>ErrorDocument</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>index.html</td>\n<td>error.html</td>\n</tr>\n</tbody>\n</table>\nThe values for specifying canned ACLs with the Tools for Windows PowerShell are the same as those used by the AWS SDK for .NET. Note, however, that these are different from the values used by the Amazon S3 Put Object action. The Tools for Windows PowerShell support the following canned ACLs:\n\n- NoACL\n- private\n- public-read\n- public-read-write\n- aws-exec-read\n- authenticated-read\n- bucket-owner-read\n- bucket-owner-full-control\n- log-delivery-write\n\nFor more information about these canned ACL settings, see [Access Control List Overview](#).\n\n### Note Regarding Multipart Upload\n\nIf you use the Amazon S3 API to upload a file that is larger than 5 GB in size, you need to use multipart upload. However, the Write-S3Object cmdlet provided by the Tools for Windows PowerShell can transparently handle file uploads that are greater than 5 GB.\n\n### Test the Website\n\nAt this point, you can test the website by navigating to it using a browser. URLs for static websites hosted in Amazon S3 follow a standard format.\n\nhttp://{bucket-name}.s3-website-{region}.amazonaws.com\n\nFor example:\n\nhttp://website-example.s3-website-us-west-1.amazonaws.com\n\n### See Also\n\n- [Using the AWS Tools for PowerShell (p. 51)](#)\n- [Put Object (Amazon S3 API Reference)](#)\n- [Canned ACLs (Amazon S3 API Reference)](#)\n\n### Delete Amazon S3 Objects and Buckets\n\nThis section describes how to delete the website that you created in preceding sections. You can simply delete the objects for the HTML files, and then delete the Amazon S3 bucket for the site.\n\nFirst, run the Remove-S3Object cmdlet to delete the objects for the HTML files from the Amazon S3 bucket.\n\n```powershell\nPS > foreach ( $obj in \"index.html\", \"error.html\" ) {\n>> Remove-S3Object -BucketName website-example -Key $obj\n> }\n```\nIsDeleteMarker\n---------\nFalse\n\nThe False response is an expected artifact of the way that Amazon S3 processes the request. In this context, it does not indicate an issue.\n\nNow you can run the `Remove-S3Bucket` cmdlet to delete the now-empty Amazon S3 bucket for the site.\n\n```\nPS > Remove-S3Bucket -BucketName website-example\nRequestId : E480ED92A2EC703D\nAmazonId2 : k6tqaqC1mMKoeYwbuJXUx1/UDa49Bj6dfLN0Ls1mWYNPHjc8/Nyvm6AGbWcc2P\nResponseStream : \nHeaders : {x-amz-id-2, x-amz-request-id, Date, Server}\nMetadata : {}\nResponseXml : \n```\n\nIn 1.1 and newer versions of the AWS Tools for PowerShell, you can add the `-DeleteBucketContent` parameter to `Remove-S3Bucket`, which first deletes all objects and object versions in the specified bucket before trying to remove the bucket itself. Depending on the number of objects or object versions in the bucket, this operation can take a substantial amount of time. In versions of the Tools for Windows PowerShell older than 1.1, the bucket had to be empty before `Remove-S3Bucket` could delete it.\n\n**Note**\n\nUnless you add the `-Force` parameter, AWS Tools for PowerShell prompts you for confirmation before the cmdlet runs.\n\n**See Also**\n\n- [Using the AWS Tools for PowerShell (p. 51)](p.51)\n- [Delete Object (Amazon S3 API Reference)](Amazon S3 API Reference)\n- [DeleteBucket (Amazon S3 API Reference)](Amazon S3 API Reference)\n\n**Upload In-Line Text Content to Amazon S3**\n\nThe `Write-S3Object` cmdlet supports the ability to upload in-line text content to Amazon S3. Using the `-Content` parameter (alias `-Text`), you can specify text-based content that should be uploaded to Amazon S3 without needing to place it into a file first. The parameter accepts simple one-line strings as well as here strings that contain multiple lines.\n\n```\nPS > # Specifying content in-line, single line text:\nPS > write-s3object mybucket -key myobject.txt -content \"file content\"\n\nPS > # Specifying content in-line, multi-line text: (note final newline needed to end in-line here-string)\nPS > write-s3object mybucket -key myobject.txt -content @\n>> line 1\n>> line 2\n>> line 3\n>> \"@'\nPS > # Specifying content from a variable: (note final newline needed to end in-line here-string)\nPS > $x = \"@\n```\n\n57\nIAM and Tools for PowerShell\n\nThis section describes some common tasks related to AWS Identity and Access Management (IAM) and how to perform them using the AWS Tools for PowerShell.\n\nThe commands shown here assume that you have set default credentials and a default region for your PowerShell session. Therefore, credentials and regions are not included in the invocation of the cmdlets.\n\nTopics\n\n- Create New IAM Users and Groups (p. 58)\n- Set an IAM Policy for an IAM User (p. 59)\n- Set an Initial Password for an IAM User (p. 60)\n\nCreate New IAM Users and Groups\n\nThis section describes how to create a new IAM group and a new IAM user and then add the user to the group.\n\nFirst, use the `New-IAMGroup` cmdlet to create the group. Although we've included it here, the `-Path` parameter is optional.\n\n```\nPS > New-IAMGroup -Path \"/ps-created-groups/\" -GroupName \"powerUsers\"\n```\n\n```\nPath : /ps-created-groups/\nGroupName : powerUsers\nGroupId : AGPAJPHUEYD5XPCG1UH3E\nArn : arn:aws:iam::455364113843:group/ps-created-groups/powerUsers\nCreateDate : 11/20/2012 3:32:50 PM\n```\n\nNext, use the `New-IAMUser` cmdlet to create the user. Similar to the preceding example, the `-Path` parameter is optional.\n\n```\nPS > New-IAMUser -Path \"/ps-created-users/\" -UserName \"myNewUser\"\n```\n\n```\nPath : /ps-created-users/\nUserName : myNewUser\nUserId : AIDAJOJSPSPXADMBT71NG\nArn : arn:aws:iam::455364113843:user/ps-created-users/myNewUser\nCreateDate : 11/20/2012 3:26:31 PM\n```\n\nFinally, use the `Add-IAMUserToGroup` cmdlet to add the user to the group.\n\n```\nPS > Add-IAMUserToGroup -UserName myNewUser -GroupName powerUsers\n```\n\nServiceResponse\n\n--------------\n\n58\nTo verify that the powerUsers group contains the myNewUser, use the Get-IAMGroup cmdlet.\n\n```\nPS > Get-IAMGroup -GroupName powerUsers\n```\n\n<table>\n<thead>\n<tr>\n<th>Group</th>\n<th>Users</th>\n<th>IsTruncated</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>------</td>\n<td>-----</td>\n<td>-----------</td>\n</tr>\n<tr>\n<td>------</td>\n<td>------</td>\n<td>----------</td>\n</tr>\n<tr>\n<td>Amazon.IdentityManagement.... {myNewUser}</td>\n<td>False</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nYou can also view IAM users and groups with the AWS Management Console\n\n- **Users View**\n- **Groups View**\n\n**See Also**\n\n- [Using the AWS Tools for PowerShell (p. 51)]\n- [Adding a New User to Your AWS Account (IAM User Guide)]\n- [CreateGroup (IAM Service Reference)]\n\n**Set an IAM Policy for an IAM User**\n\nThe following commands show how to assign an IAM policy to an IAM user. The policy specified below provides the user with \"Power User Access\". This policy is identical to the Power User Access policy template provided in the IAM console. The name for the policy shown below follows the naming convention used for IAM policy templates such as the template for Power User Access. The convention is `<template name>+<user name>+<date stamp>`\n\nIn order to specify the policy document, we use a PowerShell here-string. We assign the contents of the here-string to a variable and then use the variable as a parameter value in Write-IAMUserPolicy.\n\n```\nPS > $policyDoc = @\n { \n \"Version\": \"2012-10-17\",\n \"Statement\": [ \n { \n \"Effect\": \"Allow\",\n \"NotAction\": \"iam:*\",\n \"Resource\": \"*\"\n } \n ] \n }\nPS > Write-IAMUserPolicy -UserName myNewUser -PolicyName \"PowerUserAccess\" -PolicyDocument $policyDoc\n```\n\nServiceResponse\n\nSet an Initial Password for an IAM User\n\nThe following example demonstrates how to use the `New-IAMLoginProfile` cmdlet to set an initial password for an IAM user. For more information about character limits and recommendations for passwords, see [Password Policy Options](#) in the [IAM User Guide](#).\n\n```\nPS > New-IAMLoginProfile -UserName myNewUser -Password \"&!123!&\"\n```\n\n<table>\n<thead>\n<tr>\n<th>UserName</th>\n<th>CreateDate</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>myNewUser</td>\n<td>11/20/2012 4:23:05 PM</td>\n</tr>\n</tbody>\n</table>\n\nUse the `Update-IAMLoginProfile` cmdlet to change the password for an IAM user.\n\nSee Also\n- [Using the AWS Tools for PowerShell](#)\n- [Managing Passwords](#)\n- [CreateLoginProfile](#)\n\nAmazon EC2 and Tools for Windows PowerShell\n\nYou can perform common tasks related to Amazon EC2 using the AWS Tools for PowerShell.\n\nThe example commands shown here assume that you have set default credentials and a default region for your PowerShell session. Therefore, we don't include credentials or region when we invoke the cmdlets. For more information, see [Getting Started with the AWS Tools for Windows PowerShell](#).\n\nTopics\n- [Creating a Key Pair](#)\n- [Create a Security Group Using Windows PowerShell](#)\n- [Find an Amazon Machine Image Using Windows PowerShell](#)\n- [Launch an Amazon EC2 Instance Using Windows PowerShell](#)\n\nCreating a Key Pair\n\nThe following `New-EC2KeyPair` example creates a key pair and stores in the PowerShell variable `$myPSKeyPair`\n\n```\nPS > $myPSKeyPair = New-EC2KeyPair -KeyName myPSKeyPair\n```\n\nPipe the key pair object into the `Get-Member` cmdlet to see the object's structure.\n\n```\nPS > $myPSKeyPair | Get-Member\n```\nCreate a Key Pair\n\nTypeName: Amazon.EC2.Model.KeyPair\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>MemberType</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Equals</td>\n<td>Method</td>\n<td>bool Equals(System.Object obj)</td>\n</tr>\n<tr>\n<td>GetHashCode</td>\n<td>Method</td>\n<td>int GetHashCode()</td>\n</tr>\n<tr>\n<td>GetType</td>\n<td>Method</td>\n<td>type GetType()</td>\n</tr>\n<tr>\n<td>ToString</td>\n<td>Method</td>\n<td>string ToString()</td>\n</tr>\n<tr>\n<td>KeyFingerprint</td>\n<td>Property</td>\n<td>System.String KeyFingerprint {get;set;}</td>\n</tr>\n<tr>\n<td>KeyMaterial</td>\n<td>Property</td>\n<td>System.String KeyMaterial {get;set;}</td>\n</tr>\n<tr>\n<td>KeyName</td>\n<td>Property</td>\n<td>System.String KeyName {get;set;}</td>\n</tr>\n</tbody>\n</table>\n\nPipe the key pair object into the `Format-List` cmdlet to view values of the `KeyName`, `KeyFingerprint`, and `KeyMaterial` members. (The output has been truncated for readability.)\n\n```powershell\nPS > $myPSKeyPair | Format-List KeyName, KeyFingerprint, KeyMaterial\nKeyName : myPSKeyPair\nKeyMaterial : ----BEGIN RSA PRIVATE KEY----\n\nThe `KeyMaterial` member stores the private key for the key pair. The public key is stored in AWS. You can't retrieve the public key from AWS, but you can verify the public key by comparing the `KeyFingerprint` for the private key to that returned from AWS for the public key.\n\nViewing the Fingerprint of Your Key Pair\n\nYou can use the `Get-EC2KeyPair` cmdlet to view the fingerprint for your key pair.\n\n```powershell\nPS > Get-EC2KeyPair -KeyName myPSKeyPair | format-list KeyName, KeyFingerprint\nKeyName : myPSKeyPair\n```\n\nStoring Your Private Key\n\nTo store the private key to a file, pipe the `KeyFingerprint` member to the `Out-File` cmdlet.\n\n```powershell\nPS > $myPSKeyPair.KeyMaterial | Out-File -FilePath myPSKeyPairKeyFile\n```\nYou must specify `-Encoding ascii` when writing the private key to a file. Otherwise, tools such as `openssl` might not be able to read the file correctly. You can verify that the format of the resulting file is correct by using a command such as the following:\n\n```powershell\nPS > openssl rsa -check < myPSKeyPair.pem\n```\n\n(The `openssl` tool is not included with the AWS Tools for PowerShell or the AWS SDK for .NET.)\n\n**Removing Your Key Pair**\n\nYou need your key pair to launch and connect to an instance. When you are done using a key pair, you can remove it. To remove the public key from AWS, use the `Remove-EC2KeyPair` cmdlet. When prompted, press `Enter` to remove the key pair.\n\n```powershell\nPS > Remove-EC2KeyPair -KeyName myPSKeyPair\n```\n\nThe variable, `$myPSKeyPair`, still exists in the current PowerShell session and still contains the key pair information. The `myPSKeyPair.pem` file also exists. However, the private key is no longer valid because the public key for the key pair is no longer stored in AWS.\n\n**Create a Security Group Using Windows PowerShell**\n\nYou can use the AWS Tools for PowerShell to create and configure a security group. When you create a security group, you specify whether it is for EC2-Classic or EC2-VPC. The response is the ID of the security group.\n\nIf you need to connect to your instance, you must configure the security group to allow SSH traffic (Linux) or RDP traffic (Windows).\n\n**Topics**\n\n- Prerequisites (p. 62)\n- Creating a Security Group for EC2-Classic (p. 63)\n- Creating a Security Group for EC2-VPC (p. 64)\n\n**Prerequisites**\n\nYou need the public IP address of your computer, in CIDR notation. You can get the public IP address of your local computer using a service. For example, Amazon provides the following service: [http://checkip.amazonaws.com/](http://checkip.amazonaws.com/) or [https://checkip.amazonaws.com/](https://checkip.amazonaws.com/). To locate another service that provides your IP address, use the search phrase \"what is my IP address\". If you are connecting through an ISP or from behind your firewall without a static IP address, you need to find the range of IP addresses that can be used by your client computers.\n\n**Warning**\n\nIf you specify `0.0.0.0/0`, you are enabling traffic from any IP addresses in the world. For the SSH and RDP protocols, you might consider this acceptable for a short time in a test\nenvironment, but it's unsafe for production environments. In production, be sure to authorize access only from the appropriate individual IP address or range of addresses.\n\nCreating a Security Group for EC2-Classic\n\nWarning\nWe are retiring EC2-Classic on August 15, 2022. We recommend that you migrate from EC2-Classic to a VPC. For more information, see Migrate from EC2-Classic to a VPC in the Amazon EC2 User Guide for Linux Instances or the Amazon EC2 User Guide for Windows Instances. Also see the blog post EC2-Classic Networking is Retiring – Here’s How to Prepare.\n\nThe following example uses the New-EC2SecurityGroup cmdlet to create a security group for EC2-Classic.\n\n```\nPS > New-EC2SecurityGroup -GroupName myPSSecurityGroup -GroupDescription \"EC2-Classic from PowerShell\"\nsg-0a346530123456789\n```\n\nTo view the initial configuration of the security group, use the Get-EC2SecurityGroup cmdlet.\n\n```\nPS > Get-EC2SecurityGroup -GroupNames myPSSecurityGroup\n\nDescription : EC2-Classic from PowerShell\nGroupId : sg-0a346530123456789\nGroupName : myPSSecurityGroup\nIpPermissions : {}\nIpPermissionsEgress : {Amazon.EC2.Model.IpPermission}\nOwnerId : 123456789012\nTags : {}\nVpcId : vpc-9668ddf\n```\n\nTo configure the security group to allow inbound traffic on TCP port 22 (SSH) and TCP port 3389, use the Grant-EC2SecurityGroupIngress cmdlet. For example, the following example script shows how you could enable SSH traffic from a single IP address, 203.0.113.25/32.\n\n```\n$cidrBlocks = New-Object 'collections.generic.list[string]'\n$cidrBlocks.add(\"203.0.113.25/32\")\n$ipPermissions = New-Object Amazon.EC2.Model.IpPermission\n$ipPermissions.IpProtocol = \"tcp\"\n$ipPermissions.FromPort = 22\n$ipPermissions.ToPort = 22\nipPermissions.IpRanges = $cidrBlocks\nGrant-EC2SecurityGroupIngress -GroupName myPSSecurityGroup -IpPermissions $ipPermissions\n```\n\nTo verify the security group was updated, run the Get-EC2SecurityGroup cmdlet again. Note that you can't specify an outbound rule for EC2-Classic.\n\n```\nPS > Get-EC2SecurityGroup -GroupNames myPSSecurityGroup\n\nOwnerId : 123456789012\nGroupName : myPSSecurityGroup\nGroupId : sg-0a346530123456789\nDescription : EC2-Classic from PowerShell\nIpPermissions : {Amazon.EC2.Model.IpPermission}\nIpPermissionsEgress: {}\nVpcId :\nTags :\n```\nTo view the security group rule, use the `IpPermissions` property.\n\n```\nPS > (Get-EC2SecurityGroup -GroupNames myPSSecurityGroup).IpPermissions\n```\n\n*IpProtocol*: `tcp` \n*FromPort*: `22` \n*ToPort*: `22` \n*UserIdGroupPairs*: `{}` \n*IpRanges*: `{203.0.113.25/32}`\n\n---\n\n### Creating a Security Group for EC2-VPC\n\nThe following `New-EC2SecurityGroup` example adds the `-VpcId` parameter to create a security group for the specified VPC.\n\n```\nPS > $groupid = New-EC2SecurityGroup `-VpcId \"vpc-da0013b3\" ` `-GroupName \"myPSSecurityGroup\" ` `-GroupDescription \"EC2-VPC from PowerShell\"\n```\n\nTo verify the initial configuration of the security group, use the `Get-EC2SecurityGroup` cmdlet. By default, the security group for a VPC contains a rule that allows all outbound traffic. Notice that you can't reference a security group for EC2-VPC by name.\n\n```\nPS > Get-EC2SecurityGroup -GroupId sg-5d293231\n```\n\n*OwnerId*: `123456789012` \n*GroupName*: `myPSSecurityGroup` \n*GroupId*: `sg-5d293231` \n*Description*: `EC2-VPC from PowerShell` \n*IpPermissions*: `{}` \n*IpPermissionsEgress*: `{Amazon.EC2.Model.IpPermission}` \n*VpcId*: `vpc-da0013b3` \n*Tags*: `{}`\n\nTo define the permissions for inbound traffic on TCP port 22 (SSH) and TCP port 3389, use the `New-Object` cmdlet. The following example script defines permissions for TCP ports 22 and 3389 from a single IP address, `203.0.113.25/32`.\n\n```\n$ip1 = new-object Amazon.EC2.Model.IpPermission\n$ip1.IpProtocol = \"tcp\"\n$ip1.FromPort = 22\n$ip1.ToPort = 22\n$ip1.IpRanges.Add(\"203.0.113.25/32\")\n$ip2 = new-object Amazon.EC2.Model.IpPermission\n$ip2.IpProtocol = \"tcp\"\n$ip2.FromPort = 3389\n$ip2.ToPort = 3389\n$ip2.IpRanges.Add(\"203.0.113.25/32\")\nGrant-EC2SecurityGroupIngress -GroupId $groupid -IpPermissions @($ip1, $ip2)\n```\n\nTo verify the security group has been updated, use the `Get-EC2SecurityGroup` cmdlet again.\n\n```\nPS > Get-EC2SecurityGroup -GroupIds sg-5d293231\n```\n\n*OwnerId*: `123456789012` \n*GroupName*: `myPSSecurityGroup` \n*GroupId*: `sg-5d293231` \n*Description*: `EC2-VPC from PowerShell`\nFind an Amazon Machine Image Using Windows PowerShell\n\nWhen you launch an Amazon EC2 instance, you specify an Amazon Machine Image (AMI) to serve as a template for the instance. However, the IDs for the AWS Windows AMIs change frequently because AWS provides new AMIs with the latest updates and security enhancements. You can use the `Get-EC2Image` and `Get-EC2ImageByName` cmdlets to find the current Windows AMIs and get their IDs.\n\nTopics\n\n- `Get-EC2Image` (p. 65)\n- `Get-EC2ImageByName` (p. 66)\n\n**Get-EC2Image**\n\nThe `Get-EC2Image` cmdlet retrieves a list of AMIs that you can use.\n\nUse the `-Owner` parameter with the array value `amazon, self` so that `Get-EC2Image` retrieves only AMIs that belong to Amazon or to you. In this context, you refer to the user whose credentials you used to invoke the cmdlet.\n\n```\nPS > Get-EC2Image -Owner amazon, self\n```\n\nYou can scope the results using the `-Filter` parameter. To specify the filter, create an object of type `Amazon.EC2.Model.Filter`. For example, use the following filter to display only Windows AMIs.\n\n```\n$platform_values = New-Object 'collections.generic.list[string]' $platform_values.add(\"windows\")\n$filter_platform = New-Object Amazon.EC2.Model.Filter -Property @{Name = \"platform\"; Values = $platform_values}\nGet-EC2Image -Owner amazon, self -Filter $filter_platform\n```\n\nThe following is an example of one of the AMIs returned by the cmdlet; the actual output of the previous command provides information for many AMIs.\n<table>\n<thead>\n<tr>\n<th>Architecture</th>\n<th>x86_64</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>BlockDeviceMappings</td>\n<td>/dev/sda1, xvdca, xvdcb, xvdcc...</td>\n</tr>\n<tr>\n<td>CreationDate</td>\n<td>2019-06-12T10:41:31.000Z</td>\n</tr>\n<tr>\n<td>Description</td>\n<td>Microsoft Windows Server 2019 Full Locale English with SQL Web 2017 AMI provided by Amazon</td>\n</tr>\n<tr>\n<td>EnaSupport</td>\n<td>True</td>\n</tr>\n<tr>\n<td>Hypervisor</td>\n<td>xen</td>\n</tr>\n<tr>\n<td>ImageId</td>\n<td>ami-000226b77608d973b</td>\n</tr>\n<tr>\n<td>ImageOwnerAlias</td>\n<td>amazon</td>\n</tr>\n<tr>\n<td>ImageType</td>\n<td>machine</td>\n</tr>\n<tr>\n<td>KernelId</td>\n<td></td>\n</tr>\n<tr>\n<td>OwnerId</td>\n<td>801119661308</td>\n</tr>\n<tr>\n<td>Platform</td>\n<td>Windows</td>\n</tr>\n<tr>\n<td>ProductCodes</td>\n<td>{}</td>\n</tr>\n<tr>\n<td>Public</td>\n<td>True</td>\n</tr>\n<tr>\n<td>RamdiskId</td>\n<td></td>\n</tr>\n<tr>\n<td>RootDeviceName</td>\n<td>/dev/sda1</td>\n</tr>\n<tr>\n<td>RootDeviceType</td>\n<td>ebs</td>\n</tr>\n<tr>\n<td>SriovNetSupport</td>\n<td>simple</td>\n</tr>\n<tr>\n<td>State</td>\n<td>available</td>\n</tr>\n<tr>\n<td>StateReason</td>\n<td></td>\n</tr>\n<tr>\n<td>Tags</td>\n<td>{}</td>\n</tr>\n<tr>\n<td>VirtualizationType</td>\n<td>hvm</td>\n</tr>\n</tbody>\n</table>\n\n### Get-EC2ImageByName\n\nThe Get-EC2ImageByName cmdlet enables you to filter the list of AWS Windows AMIs based on the type of server configuration you are interested in.\n\nWhen run with no parameters, as follows, the cmdlet emits the complete set of current filter names:\n\n```powershell\nPS > Get-EC2ImageByName\n\nWINDOWS_2016_BASE\nWINDOWS_2016_NANO\nWINDOWS_2016_CORE\nWINDOWS_2016_CONTAINER\nWINDOWS_2016_SQL_SERVER.ENTERPRISE_2016\nWINDOWS_2016_SQL_SERVER.STANDARD_2016\nWINDOWS_2016_SQL_SERVER.WEB_2016\nWINDOWS_2016_SQL_SERVER.EXPRESS_2016\nWINDOWS_2012R2_BASE\nWINDOWS_2012R2_CORE\nWINDOWS_2012R2_SQL_SERVER.EXPRESS_2016\nWINDOWS_2012R2_SQL_SERVER.STANDARD_2016\nWINDOWS_2012R2_SQL_SERVER.WEB_2016\nWINDOWS_2012R2_SQL_SERVER.EXPRESS_2014\nWINDOWS_2012R2_SQL_SERVER.STANDARD_2014\nWINDOWS_2012R2_SQL_SERVER.WEB_2014\nWINDOWS_2012_BASE\nWINDOWS_2012_SQL_SERVER.EXPRESS_2014\nWINDOWS_2012_SQL_SERVER.STANDARD_2014\nWINDOWS_2012_SQL_SERVER.WEB_2014\nWINDOWS_2012_SQL_SERVER.EXPRESS_2012\nWINDOWS_2012_SQL_SERVER.STANDARD_2012\nWINDOWS_2012_SQL_SERVER.WEB_2012\nWINDOWS_2012_SQL_SERVER.EXPRESS_2008\nWINDOWS_2012_SQL_SERVER.STANDARD_2008\nWINDOWS_2012_SQL_SERVER.WEB_2008\nWINDOWS_2008R2_BASE\nWINDOWS_2008R2_SQL_SERVER.EXPRESS_2012\n```\nTo narrow the set of images returned, specify one or more filter names using the Names parameter.\n\n```\nPS > Get-EC2ImageByName -Names WINDOWS_2016_CORE\n```\n\n### Launch an Amazon EC2 Instance Using Windows PowerShell\n\nTo launch an Amazon EC2 instance, you need the key pair and security group that you created in the previous sections. You also need the ID of an Amazon Machine Image (AMI). For more information, see the following documentation:\n\n- [Creating a Key Pair](#) (p. 60)\n- [Create a Security Group Using Windows PowerShell](#) (p. 62)\n- [Find an Amazon Machine Image Using Windows PowerShell](#) (p. 65)\n\n**Important**\n\nIf you launch an instance that is not within the Free Tier, you are billed after you launch the instance and charged for the time that the instance is running even if it remains idle.\n• Launching an Instance in EC2-Classic (p. 68)\n• Launching an Instance in a VPC (p. 69)\n• Launching a Spot Instance in a VPC (p. 70)\n\nLaunching an Instance in EC2-Classic\n\nWarning\nWe are retiring EC2-Classic on August 15, 2022. We recommend that you migrate from EC2-Classic to a VPC. For more information, see Migrate from EC2-Classic to a VPC in the Amazon EC2 User Guide for Linux Instances or the Amazon EC2 User Guide for Windows Instances. Also see the blog post EC2-Classic Networking is Retiring – Here’s How to Prepare.\n\nThe following command creates and launches a single t1.micro instance.\n\n```\nPS > New-EC2Instance -ImageId ami-c49c0dac ` -MinCount 1 ` -MaxCount 1 ` -KeyName myPSKeyPair ` -SecurityGroups myPSSecurityGroup ` -InstanceType t1.micro\n\nReservationId : r-b70a0ef1\nOwnerId : 123456789012\nRequesterId : \nGroups : {myPSSecurityGroup}\nGroupName : {myPSSecurityGroup}\nInstances : {}\n```\n\nYour instance is in the pending state initially, but is in the running state after a few minutes. To view information about your instance, use the Get-EC2Instance cmdlet. If you have more than one instance, you can filter the results on the reservation ID using the Filter parameter. First, create an object of type Amazon.EC2.Model.Filter. Next, call Get-EC2Instance that uses the filter, and then displays the Instances property.\n\n```\nPS > $reservation = New-Object 'collections.generic.list[string]' \nPS > $reservation.add(\"r-5caa4371\") \nPS > $filter_reservation = New-Object Amazon.EC2.Model.Filter -Property @{Name = \"reservation-id\"; Values = $reservation} \nPS > (Get-EC2Instance -Filter $filter_reservation).Instances\n```\n\nAmiLaunchIndex : 0\nArchitecture : x86_64\nBlockDeviceMappings : {/dev/sda1}\nClientToken : \nEbsOptimized : False\nHypervisor : xen\nIamInstanceProfile : \nImageId : ami-c49c0dac\nInstanceId : i-5203422c\nInstanceLifecycle : \nInstanceType : t1.micro\nKernelId : \nKeyName : myPSKeyPair\nLaunchTime : 12/2/2018 3:38:52 PM\nMonitoring : Amazon.EC2.Model.Monitoring\nNetworkInterfaces : {}\nPlacement : Amazon.EC2.Model.Placement\nPlatform : Windows\nPrivateDnsName : \nPrivateIpAddress : 10.25.1.11\nLaunching an Instance in a VPC\n\nThe following command creates a single m1.small instance in the specified private subnet. The security group must be valid for the specified subnet.\n\n```\nPS > New-EC2Instance -ImageId ami-c49c0dac -MinCount 1 -MaxCount 1 -KeyName myPSKeyPair -SecurityGroupId sg-5d293231 -InstanceType m1.small -SubnetId subnet-d60013bf\n```\n\nYour instance is in the pending state initially, but is in the running state after a few minutes. To view information about your instance, use the Get-EC2Instance cmdlet. If you have more than one instance, you can filter the results on the reservation ID using the Filter parameter. First, create an object of type Amazon.EC2.Model.Filter. Next, call Get-EC2Instance that uses the filter, and then displays the Instances property.\n\n```\nPS > $reservation = New-Object 'collections.generic.list[string]'\nPS > $reservation.add(\"r-b70a0ef1\")\nPS > $filter_reservation = New-Object Amazon.EC2.Model.Filter -Property @{\n Name = \"reservation-id\"; Values = $reservation\n}\nPS > (Get-EC2Instance -Filter $filter_reservation).Instances\n```\n\n```\nAmiLaunchIndex : 0\nArchitecture : x86_64\nBlockDeviceMappings : (/dev/sda1)\nClientToken : \nEbsOptimized : False\nHypervisor : xen\nIamInstanceProfile : \nImageId : ami-c49c0dac\nInstanceId : i-5203422c\nInstanceLifecycle : \nInstanceType : m1.small\nKernelId : \n```\nLaunching a Spot Instance in a VPC\n\nThe following example script requests a Spot Instance in the specified subnet. The security group must be one you created for the VPC that contains the specified subnet.\n\n```powershell\n$interface1 = New-Object Amazon.EC2.Model.InstanceNetworkInterfaceSpecification\n$interface1.DeviceIndex = 0\n$interface1.SubnetId = \"subnet-b61f49f0\"\n$interface1.PrivateIpAddress = \"10.0.1.5\"\n$interface1.Groups.Add(\"sg-5d293231\")\nRequest-EC2SpotInstance\n -SpotPrice 0.007\n -InstanceCount 1\n -Type one-time\n -LaunchSpecification_ImageId ami-7527031c\n -LaunchSpecification_InstanceType m1.small\n -Region us-west-2\n -LaunchSpecification_NetworkInterfaces $interface1\n```\n\nAWS Lambda and AWS Tools for PowerShell\n\nBy using the AWSLambdaPSCore module, you can develop AWS Lambda functions in PowerShell Core 6.0 using the .NET Core 2.1 runtime. PowerShell developers can manage AWS resources and write automation scripts in the PowerShell environment by using Lambda. PowerShell support in Lambda lets you run PowerShell scripts or functions in response to any Lambda event, such as an Amazon S3 event or Amazon CloudWatch scheduled event. The AWSLambdaPSCore module is a separate AWS module for PowerShell; it is not part of the AWS Tools for PowerShell, nor does installing the AWSLambdaPSCore module install the AWS Tools for PowerShell.\n\nAfter you install the AWSLambdaPSCore module, you can use any available PowerShell cmdlets—or develop your own—to author serverless functions. The AWS Lambda Tools for PowerShell module includes project templates for PowerShell-based serverless applications, and tools to publish projects to AWS.\nAWSLambdaPSCore module support is available in all regions that support Lambda. For more information about supported regions, see the [AWS region table](#).\n\n## Prerequisites\n\nThe following steps are required before you can install and use the AWSLambdaPSCore module. For more detail about these steps, see [Setting Up a PowerShell Development Environment](#) in the AWS Lambda Developer Guide.\n\n- **Install the correct release of PowerShell** – Lambda's support for PowerShell is based on the cross-platform PowerShell Core 6.0 release. You can develop PowerShell Lambda functions on Windows, Linux, or Mac. If you don’t have at least this release of PowerShell installed, instructions are available on the [Microsoft PowerShell documentation website](#).\n\n- **Install the .NET Core 2.1 SDK** – Because PowerShell Core is based on .NET Core, the Lambda support for PowerShell uses the same .NET Core 2.1 Lambda runtime for both .NET Core and PowerShell Lambda functions. The Lambda PowerShell publishing cmdlets use the .NET Core 2.1 SDK to create the Lambda deployment package. The .NET Core 2.1 SDK is available from the [Microsoft Download Center](#). Be sure to install the SDK, not the Runtime.\n\n## Install the AWSLambdaPSCore Module\n\nAfter completing the prerequisites, you are ready to install the AWSLambdaPSCore module. Run the following command in a PowerShell Core session.\n\n```powershell\nPS> Install-Module AWSLambdaPSCore -Scope CurrentUser\n```\n\nYou are ready to start developing Lambda functions in PowerShell. For more information about how to get started, see [Programming Model for Authoring Lambda Functions in PowerShell](#) in the AWS Lambda Developer Guide.\n\n## See Also\n\n- [Announcing Lambda Support for PowerShell Core on the AWS Developer Blog](#)\n- [AWSLambdaPSCore module on the PowerShell Gallery website](#)\n- [Setting Up a PowerShell Development Environment](#)\n- [AWS Lambda Tools for Powershell on GitHub](#)\n- [AWS Lambda Console](#)\n\n## Amazon SQS, Amazon SNS and Tools for Windows PowerShell\n\nThis section provides examples that show how to:\n\n- Create an Amazon SQS queue and get queue ARN (Amazon Resource Name).\n- Create an Amazon SNS topic.\n- Give permissions to the SNS topic so that it can send messages to the queue.\n- Subscribe the queue to the SNS topic.\n- Give IAM users or AWS accounts permissions to publish to the SNS topic and read messages from the SQS queue.\n• Verify results by publishing a message to the topic and reading the message from the queue.\n\nCreate an Amazon SQS queue and get queue ARN\n\nThe following command creates an SQS queue in your default region. The output shows the URL of the new queue.\n\n```\nPS > New-SQSQueue -QueueName myQueue\nhttps://sqs.us-west-2.amazonaws.com/123456789012/myQueue\n```\n\nThe following command retrieves the ARN of the queue.\n\n```\nPS > Get-SQSQueueAttribute -QueueUrl https://sqs.us-west-2.amazonaws.com/123456789012/myQueue -AttributeName QueueArn\n... QueueARN : arn:aws:sqs:us-west-2:123456789012:myQueue\n...```\n\nCreate an Amazon SNS topic\n\nThe following command creates an SNS topic in your default region, and returns the ARN of the new topic.\n\n```\nPS > New-SNSTopic -Name myTopic\n```\n\nGive permissions to the SNS topic\n\nThe following example script creates both an SQS queue and an SNS topic, and grants permissions to the SNS topic so that it can send messages to the SQS queue:\n\n```\n# create the queue and topic to be associated\n$qurl = New-SQSQueue -QueueName \"myQueue\"\n$topicarn = New-SNSTopic -Name \"myTopic\"\n\n# get the queue ARN to inject into the policy; it will be returned\n# in the output's QueueARN member but we need to put it into a variable\n# so text expansion in the policy string takes effect\n$qarn = (Get-SQSQueueAttribute -QueueUrl $qurl -AttributeNames \"QueueArn\").QueueARN\n\n# construct the policy and inject arns\n$policy = @\"{\n \"Version\": \"2012-10-17\",\n \"Statement\": {\n \"Effect\": \"Allow\",\n \"Principal\": \"*\",\n \"Action\": \"SQS:SendMessage\",\n \"Resource\": \"$qarn\",\n \"Condition\": { \"ArnEquals\": { \"aws:SourceArn\": \"$topicarn\" } }\n }\n}\n\"\"\n\n# set the policy\nSet-SQSQueueAttribute -QueueUrl $qurl -Attribute @{ Policy=$policy }\n```\nSubscribe the queue to the SNS topic\n\nThe following command subscribes the queue myQueue to the SNS topic myTopic, and returns the Subscription ID:\n\n```\nPS > Connect-SNSNotification\n -Protocol SQS\n\narn:aws:sns:us-west-2:123456789012:myTopic:f8ff77c6-e719-4d70-8e5c-a54d41feb754\n```\n\nGive permissions\n\nThe following command grants permission to perform the sns:Publish action on the topic myTopic\n\n```\nPS > Add-SNSPermission\n -Label ps-cmdlet-topic\n -AWSAccountIds 123456789012\n -ActionNames publish\n```\n\nThe following command grants permission to perform the sqs:ReceiveMessage and sqs:DeleteMessage actions on the queue myQueue.\n\n```\nPS > Add-SQSPermission\n -QueueUrl https://sqs.us-west-2.amazonaws.com/123456789012/myQueue\n -AWSAccountId \"123456789012\"\n -Label queue-permission\n -ActionName SendMessage, ReceiveMessage\n```\n\nVerify results\n\nThe following command tests your new queue and topic by publishing a message to the SNS topic myTopic and returns the MessageId.\n\n```\nPS > Publish-SNSMessage\n -Message \"Have A Nice Day!\"\n\n728180b6-f62b-49d5-b4d3-3824bb2e77f4\n```\n\nThe following command retrieves the message from the SQS queue myQueue and displays it.\n\n```\nAttributes : {}\nBody : \n \"Type\" : \"Notification\",\n \"MessageId\" : \"491c687d-b78d-5c48-b7a0-3d8d769ee91b\",\n \"Message\" : \"Have A Nice Day!\",\n \"Timestamp\" : \"2019-09-09T21:06:27.201Z\",\n \"SignatureVersion\" : \"1\",\n \"Signature\" : \"llE17A2+XOuJZnw3TlgcXz4KPLXZxbxoEMIirelhl3u/\n oxkWm5z+9tJKFMns1ZOqQvKxkz+ExfEzc05yW6biVuB8pyRmZ1b3HtUEN13ayv2WQi0T1vlpLpM7VEQNSm+hL1iPFcs\n vyuGkJReV71OjWPHmcN\n +qTE21ld2RPkF0eGtLGawTsSPTWEv3dDblL1f7E0z0q1n1XTu7psZ8Swx01X3Q06u9i9qBf70ek3FZJNp6Avu05hIkly\n 4yoRs1IkbLVy0a8Y191Wp7a7EoWaBn0zhCSe70\n```\nCloudWatch from the AWS Tools for Windows PowerShell\n\nThis section shows an example of how to use the Tools for Windows PowerShell to publish custom metric data to CloudWatch.\n\nThis example assumes that you have set default credentials and a default region for your PowerShell session.\n\nPublish a Custom Metric to Your CloudWatch Dashboard\n\nThe following PowerShell code initializes an CloudWatch MetricDatum object and posts it to the service. You can see the result of this operation by navigating to the CloudWatch console.\n\n```powershell\n$dat = New-Object Amazon.CloudWatch.Model.MetricDatum\n$dat.Timestamp = (Get-Date).ToUniversalTime()\n$dat.MetricName = \"New Posts\"\n$dat.Unit = \"Count\"\n$dat.Value = \".50\"\nWrite-CWMetricData -Namespace \"Usage Metrics\" -MetricData $dat\n```\n\nNote the following:\n\n- The date-time information that you use to initialize $dat.Timestamp must be in Universal Time (UTC).\n- The value that you use to initialize $dat.Value can be either a string value enclosed in quotes, or a numeric value (no quotes). The example shows a string value.\n\nSee Also\n\n- Using the AWS Tools for PowerShell (p. 51)\nUsing the ClientConfig parameter in cmdlets\n\nThe ClientConfig parameter can be used to specify certain configuration settings when you connect to a service. Most of the possible properties of this parameter are defined in the Amazon.Runtime.ClientConfig class, which is inherited into the APIs for AWS services. For an example of simple inheritance, see the Amazon.Keyspaces.AmazonKeyspacesConfig class. In addition, some services define additional properties that are appropriate only for that service. For an example of additional properties that have been defined, see the Amazon.S3.AmazonS3Config class, specifically the ForcePathStyle property.\n\nUsing the ClientConfig parameter\n\nTo use the ClientConfig parameter, you can specify it on the command line as a ClientConfig object or use PowerShell splatting to pass a collection of parameter values to a command as a unit. These methods are shown in the following examples. The examples assume that the AWS.Tools.S3 module has been installed and imported, and that you have a [default] credentials profile with appropriate permissions.\n\nDefining a ClientConfig object\n\n```powershell\n$s3Config = New-Object -TypeName Amazon.S3.AmazonS3Config\n$s3Config.ForcePathStyle = $true\n$s3Config.Timeout = [TimeSpan]::FromMilliseconds(150000)\nGet-S3Object -BucketName <BUCKET_NAME> -ClientConfig $s3Config\n```\n\nAdding ClientConfig properties by using PowerShell splatting\n\n```powershell\n$params=@{\n ClientConfig=@{\n ForcePathStyle=$true\n Timeout=[TimeSpan]::FromMilliseconds(150000)\n }\n BucketName=\"<BUCKET_NAME>\"\n}\nGet-S3Object @params\n```\n\nUsing an undefined property\n\nWhen using PowerShell splatting, if you specify a ClientConfig property that doesn't exist, the AWS Tools for PowerShell doesn't detect the error until runtime, at which time it returns an exception. Modifying the example from above:\n\n```powershell\n$params=@{\n ClientConfig=@{\n ForcePathStyle=$true\n UndefinedProperty=\"Value\"\n Timeout=[TimeSpan]::FromMilliseconds(150000)\n }\n BucketName=\"<BUCKET_NAME>\"\n}```\nSpecifying the AWS Region\n\nYou can use the ClientConfig parameter to set the AWS Region for the command. The Region is set through the RegionEndpoint property. The AWS Tools for PowerShell calculates the Region to use according to the following precedence:\n\n1. The -Region parameter\n2. The Region passed in the ClientConfig parameter\n3. The PowerShell session state\n4. The shared AWS config file\n5. The environment variables\n6. The Amazon EC2 instance metadata, if enabled.\nSecurity in the AWS Tools for PowerShell\n\nCloud security at AWS is the highest priority. As an AWS customer, you benefit from a data center and network architecture that is built to meet the requirements of the most security-sensitive organizations.\n\nSecurity is a shared responsibility between AWS and you. The shared responsibility model describes this as security of the cloud and security in the cloud:\n\n- **Security of the cloud** – AWS is responsible for protecting the infrastructure that runs AWS services in the AWS Cloud. AWS also provides you with services that you can use securely. Third-party auditors regularly test and verify the effectiveness of our security as part of the AWS Compliance Programs. To learn about the compliance programs that apply to AWS Tools for PowerShell, see AWS Services in Scope by Compliance Program.\n\n- **Security in the cloud** – Your responsibility is determined by the AWS service that you use. You are also responsible for other factors including the sensitivity of your data, your company’s requirements, and applicable laws and regulations.\n\nThis documentation helps you understand how to apply the shared responsibility model when using the AWS Tools for PowerShell. The following topics show you how to configure the AWS Tools for PowerShell to meet your security and compliance objectives. You also learn how to use the AWS Tools for PowerShell to help you to monitor and secure your AWS resources.\n\n**Topics**\n- [Data protection in the AWS Tools for PowerShell (p. 77)](#)\n- [Identity and Access Management for the AWS Tools for PowerShell (p. 78)](#)\n- [Compliance Validation for the AWS Tools for PowerShell (p. 79)](#)\n\nData protection in the AWS Tools for PowerShell\n\nThe AWS shared responsibility model applies to data protection in the AWS Tools for PowerShell. As described in this model, AWS is responsible for protecting the global infrastructure that runs all of the AWS Cloud. You are responsible for maintaining control over your content that is hosted on this infrastructure. This content includes the security configuration and management tasks for the AWS services that you use. For more information about data privacy, see the Data Privacy FAQ. For information about data protection in Europe, see the AWS Shared Responsibility Model and GDPR blog post on the AWS Security Blog.\n\nFor data protection purposes, we recommend that you protect AWS account credentials and set up individual users with AWS IAM Identity Center (successor to AWS Single Sign-On) or AWS Identity and Access Management (IAM). That way, each user is given only the permissions necessary to fulfill their job duties. We also recommend that you secure your data in the following ways:\n\n- Use multi-factor authentication (MFA) with each account.\n- Use SSL/TLS to communicate with AWS resources. We require TLS 1.2 and recommend TLS 1.3.\n- Set up API and user activity logging with AWS CloudTrail.\n- Use AWS encryption solutions, along with all default security controls within AWS services.\n• Use advanced managed security services such as Amazon Macie, which assists in discovering and securing sensitive data that is stored in Amazon S3.\n• If you require FIPS 140-2 validated cryptographic modules when accessing AWS through a command line interface or an API, use a FIPS endpoint. For more information about the available FIPS endpoints, see Federal Information Processing Standard (FIPS) 140-2.\n\nWe strongly recommend that you never put confidential or sensitive information, such as your customers' email addresses, into tags or free-form text fields such as a Name field. This includes when you work with the AWS Tools for PowerShell or other AWS services using the console, API, AWS CLI, or AWS SDKs. Any data that you enter into tags or free-form text fields used for names may be used for billing or diagnostic logs. If you provide a URL to an external server, we strongly recommend that you do not include credentials information in the URL to validate your request to that server.\n\nData encryption\n\nA key feature of any secure service is that information is encrypted when it is not being actively used.\n\nEncryption at Rest\n\nThe AWS Tools for PowerShell does not itself store any customer data other than the credentials it needs to interact with the AWS services on the user’s behalf.\n\nIf you use the AWS Tools for PowerShell to invoke an AWS service that transmits customer data to your local computer for storage, then refer to the Security & Compliance chapter in that service’s User Guide for information on how that data is stored, protected, and encrypted.\n\nEncryption in Transit\n\nBy default, all data transmitted from the client computer running the AWS Tools for PowerShell and AWS service endpoints is encrypted by sending everything through an HTTPS/TLS connection.\n\nYou don't need to do anything to enable the use of HTTPS/TLS. It is always enabled.\n\nIdentity and Access Management for the AWS Tools for PowerShell\n\nThe AWS Tools for PowerShell uses the same IAM users and roles that you use to access your AWS resources and their services with the AWS Management Console. The policies that grant permissions are also the same because the AWS Tools for PowerShell calls the same API operations that are used by the service console. For more information, see the \"Identity and Access Management\" section in the \"Security\" chapter for the AWS service that you want to use.\n\nThe only major difference is how you authenticate when using a standard IAM user and long-term credentials. Although an IAM user requires a password to access an AWS service’s console, that same IAM user requires an access key instead of a password to perform the same operations using the AWS Tools for PowerShell. All other short-term credentials are used in the same way they are used with the console.\n\nThe credentials used by the AWS Tools for PowerShell are typically stored in plaintext files and are not encrypted. However, you do have an option to use the encrypted .NET SDK credential store when you run on Windows.\n\n• The $HOME/.aws/credentials file stores long-term credentials required to access your AWS resources. These include your access key ID and secret access key.\nMitigation of Risk\n\n- We strongly recommend that you configure your file system permissions on the $HOME/.aws folder and its child folders and files to restrict access to only authorized users.\n- Use roles with temporary credentials wherever possible to reduce the opportunity for damage if the credentials are compromised. Use long-term credentials only to request and refresh short-term role credentials.\n\nCompliance Validation for the AWS Tools for PowerShell\n\nThird-party auditors assess the security and compliance of AWS services as part of multiple AWS compliance programs. Using the AWS Tools for PowerShell to access a service does not alter that service's compliance.\n\nFor a list of AWS services in scope of specific compliance programs, see AWS Services in Scope by Compliance Program. For general information, see AWS Compliance Programs.\n\nYou can download third-party audit reports using the AWS Artifact. For more information, see Downloading Reports in AWS Artifact.\n\nYour compliance responsibility when using AWS Tools for PowerShell is determined by the sensitivity of your data, your company's compliance objectives, and applicable laws and regulations. AWS provides the following resources to help with compliance:\n\n- **Security and Compliance Quick Start Guides** – These deployment guides discuss architectural considerations and provide steps for deploying security- and compliance-focused baseline environments on AWS.\n- **Architecting for HIPAA Security and Compliance Whitepaper** – This whitepaper describes how companies can use AWS to create HIPAA-compliant applications.\n- **AWS Compliance Resources** – This collection of workbooks and guides might apply to your industry and location.\n- **Evaluating Resources with Rules** in the AWS Config Developer Guide – The AWS Config service assesses how well your resource configurations comply with internal practices, industry guidelines, and regulations.\n- **AWS Security Hub** – This AWS service provides a comprehensive view of your security state within AWS that helps you check your compliance with security industry standards and best practices.\n# Document History\n\nThis topic describes significant changes to the documentation for the AWS Tools for PowerShell.\n\nWe also update the documentation periodically in response to customer feedback. To send feedback about a topic, use the feedback buttons next to \"Did this page help you?\" located at the bottom of each page.\n\nFor additional information about changes and updates to the AWS Tools for PowerShell, see the release notes.\n\n<table>\n<thead>\n<tr>\n<th>Change</th>\n<th>Description</th>\n<th>Date</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Pipelining and <code>$AWSHistory</code> (p. 41)</td>\n<td>Added the IncludeSensitiveData parameter to the <code>Set-AWSHistoryConfiguration</code> cmdlet.</td>\n<td>March 9, 2023</td>\n</tr>\n<tr>\n<td>Using the ClientConfig parameter in cmdlets (p. 75)</td>\n<td>Added information about support for the ClientConfig parameter.</td>\n<td>October 28, 2022</td>\n</tr>\n<tr>\n<td>Launch an Amazon EC2 Instance Using Windows PowerShell (p. 67)</td>\n<td>Added notes about retiring EC2-Classic.</td>\n<td>July 26, 2022</td>\n</tr>\n<tr>\n<td>AWS Tools for PowerShell Version 4 (p. 80)</td>\n<td>Added information about version 4, including installation instructions for both Windows and Linux/macOS, and a migration topic that describes the differences from version 3 and introduces new features.</td>\n<td>November 21, 2019</td>\n</tr>\n<tr>\n<td>AWS Tools for PowerShell 3.3.563 (p. 80)</td>\n<td>Added information about how to install and use the preview version of the AWS.Tools.Common module. This new module breaks apart the older monolithic package into one shared module and one module per AWS service.</td>\n<td>October 18, 2019</td>\n</tr>\n<tr>\n<td>AWS Tools for PowerShell 3.3.343.0 (p. 80)</td>\n<td>Added information to the Using the AWS Tools for PowerShell section introducing the AWS Lambda Tools for PowerShell for PowerShell Core developers to build AWS Lambda functions.</td>\n<td>September 11, 2018</td>\n</tr>\n<tr>\n<td>AWS Tools for Windows PowerShell 3.1.31.0 (p. 80)</td>\n<td>Added information to the Getting Started section about new cmdlets that use Security Assertion Markup Language (SAML) to support configuring federated identity for users.</td>\n<td>December 1, 2015</td>\n</tr>\n<tr>\n<td>AWS Tools for Windows PowerShell 2.3.19 (p. 80)</td>\n<td>Added information to the <a href=\"#\">Cmdlets Discovery and Aliases</a> section about the new <code>Get-AWSCmdletName</code> cmdlet that can help users more easily find their desired AWS cmdlets.</td>\n<td>February 5, 2015</td>\n</tr>\n<tr>\n<td>AWS Tools for Windows PowerShell 1.1.1.0 (p. 80)</td>\n<td>Collection output from cmdlets is always enumerated to the PowerShell pipeline. Automatic support for pageable service calls. New <code>$AWSHistory</code> shell variable collects service responses and optionally service requests. AWSRegion instances use Region field instead of SystemName to aid pipelining. Remove-S3Bucket supports a <code>-DeleteObjects</code> switch option. Fixed usability issue with <code>Set-AWSCredentials</code>. <code>Initialize-AWSDefaults</code> reports from where it obtained credentials and region data. <code>Stop-EC2Instance</code> accepts <code>Amazon.EC2.Model.Reservation</code> instances as input. Generic <code>List<T></code> parameter types replaced with array types (<code>T[]</code>). Cmdlets that delete or terminate resources prompt for confirmation prior to deletion. <code>Write-S3Object</code> supports inline text content to upload to Amazon S3.</td>\n<td>May 15, 2013</td>\n</tr>\n</tbody>\n</table>\nAWS Tools for Windows PowerShell 1.0.1.0 (p. 80)\n\nThe install location of the Tools for Windows PowerShell module has changed so that environments using Windows PowerShell version 3 can take advantage of auto-loading. The module and supporting files are now installed to an AWSPowerShell subfolder beneath AWS ToolsPowerShell. Files from previous versions that exist in the AWS ToolsPowerShell folder are automatically removed by the installer. The $PSModulePath for Windows PowerShell (all versions) is updated in this release to contain the parent folder of the module (AWS ToolsPowerShell). For systems with Windows PowerShell version 2, the Start Menu shortcut is updated to import the module from the new location and then run Initialize-AWSDefaults. For systems with Windows PowerShell version 3, the Start Menu shortcut is updated to remove the Import-Module command, leaving just Initialize-AWSDefaults. If you edited your PowerShell profile to perform an Import-Module of the AWSPowerShell.psd1 file, you will need to update it to point to the file's new location (or, if using PowerShell version 3, remove the Import-Module statement as it is no longer needed). As a result of these changes, the Tools for Windows PowerShell module is now listed as an available module when executing Get-Module -ListAvailable. In addition, for users of Windows PowerShell version 3, the execution of any cmdlet exported by the module will automatically load the module in the current PowerShell shell without needing to use Import-Module first. This enables interactive\n<table>\n<thead>\n<tr>\n<th>AWS Tools for Windows PowerShell 1.0.0.0 (p. 80)</th>\n<th>Initial release</th>\n<th>December 6, 2012</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>use of the cmdlets on a system with an execution policy that disallows script execution.</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>"}}},{"rowIdx":54,"cells":{"id":{"kind":"string","value":"0265a25b8771312c9c28afa3c1eb2e0235fc59dd"},"text":{"kind":"string","value":"GeneralDisclaimer\n\nOne or more of the Following Statements may affect this Document\n\n- This document has been reproduced from the best copy furnished by the organizational source. It is being released in the interest of making available as much information as possible.\n\n- This document may contain data, which exceeds the sheet parameters. It was furnished in this condition by the organizational source and is the best copy available.\n\n- This document may contain tone-on-tone or color graphs, charts and/or pictures, which have been reproduced in black and white.\n\n- This document is paginated as submitted by the original source.\n\n- Portions of this document are not fully legible due to the historical nature of some of the material. However, it is the best reproduction available from the original submission.\n\nProduced by the NASA Center for Aerospace Information (CASI)\nPAYLOAD SOFTWARE TECHNOLOGY\n\nSOFTWARE TECHNOLOGY DEVELOPMENT PLAN\n\nJune 22, 1977\n\nPrepared for:\nGeorge C. Marshall Space Flight Center\nNational Aeronautics Space Administration\nMarshall Space Flight Center, Alabama 35812\n## TABLE OF CONTENTS\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>LIST OF FIGURES</td>\n<td>vi</td>\n</tr>\n<tr>\n<td>1. INTRODUCTION</td>\n<td>1</td>\n</tr>\n<tr>\n<td>1.1 Purpose</td>\n<td>1</td>\n</tr>\n<tr>\n<td>1.2 Scope</td>\n<td>1</td>\n</tr>\n<tr>\n<td>1.3 Organization</td>\n<td>3</td>\n</tr>\n<tr>\n<td>1.4 References</td>\n<td>6</td>\n</tr>\n<tr>\n<td>2. SUMMARY</td>\n<td>7</td>\n</tr>\n<tr>\n<td>2.1 Description of Software Technology Development Items</td>\n<td>7</td>\n</tr>\n<tr>\n<td>2.2 Relation to Other Technology Development</td>\n<td>11</td>\n</tr>\n<tr>\n<td>2.3 Identification of Priorities</td>\n<td>13</td>\n</tr>\n<tr>\n<td>2.4 Development Schedule</td>\n<td>15</td>\n</tr>\n<tr>\n<td>3. SOFTWARE TECHNOLOGY ITEM DEVELOPMENT PLANS</td>\n<td>19</td>\n</tr>\n<tr>\n<td>3.1 Requirements Decomposition and Structuring Guidelines (TI-01)</td>\n<td>19</td>\n</tr>\n<tr>\n<td>3.1.1 Problem Definition</td>\n<td>19</td>\n</tr>\n<tr>\n<td>3.1.2 Technology Development Requirements</td>\n<td>19</td>\n</tr>\n<tr>\n<td>3.1.3 Suggested Approach</td>\n<td>19</td>\n</tr>\n<tr>\n<td>3.1.4 Schedule and Resources</td>\n<td>20</td>\n</tr>\n<tr>\n<td>3.1.5 Verification of Results</td>\n<td>20</td>\n</tr>\n<tr>\n<td>3.1.6 Related Studies</td>\n<td>20</td>\n</tr>\n<tr>\n<td>3.2 Requirements-to-Code Translation Aids (TI-02)</td>\n<td>23</td>\n</tr>\n<tr>\n<td>3.2.1 Problem Definition</td>\n<td>23</td>\n</tr>\n<tr>\n<td>3.2.2 Technology Development Requirements</td>\n<td>23</td>\n</tr>\n<tr>\n<td>3.2.3 Suggested Approach</td>\n<td>23</td>\n</tr>\n<tr>\n<td>3.2.4 Schedule and Resources</td>\n<td>24</td>\n</tr>\n<tr>\n<td>3.2.5 Verification of Results</td>\n<td>24</td>\n</tr>\n<tr>\n<td>3.2.6 Related Studies</td>\n<td>24</td>\n</tr>\n</tbody>\n</table>\n## TABLE OF CONTENTS (Continued)\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>3.3</strong> Simplified Development System Demonstration Model (TI-03)</td>\n<td>25</td>\n</tr>\n<tr>\n<td>3.3.1 Problem Definition</td>\n<td>25</td>\n</tr>\n<tr>\n<td>3.3.2 Technology Development Requirements</td>\n<td>25</td>\n</tr>\n<tr>\n<td>3.3.3 Suggested Approach</td>\n<td>25</td>\n</tr>\n<tr>\n<td>3.3.4 Schedule and Resources</td>\n<td>26</td>\n</tr>\n<tr>\n<td>3.3.5 Verification of Results</td>\n<td>26</td>\n</tr>\n<tr>\n<td>3.3.6 Related Studies</td>\n<td>26</td>\n</tr>\n<tr>\n<td><strong>3.4</strong> Query-Guided Implementation Methods (TI-04)</td>\n<td>27</td>\n</tr>\n<tr>\n<td>3.4.1 Problem Definition</td>\n<td>27</td>\n</tr>\n<tr>\n<td>3.4.2 Technology Development Requirements</td>\n<td>27</td>\n</tr>\n<tr>\n<td>3.4.3 Suggested Approach</td>\n<td>27</td>\n</tr>\n<tr>\n<td>3.4.4 Schedule and Resources</td>\n<td>28</td>\n</tr>\n<tr>\n<td>3.4.5 Verification of Results</td>\n<td>28</td>\n</tr>\n<tr>\n<td>3.4.6 Related Studies</td>\n<td>28</td>\n</tr>\n<tr>\n<td><strong>3.5</strong> Standardization Criteria for NASA Software (TI-05)</td>\n<td>29</td>\n</tr>\n<tr>\n<td>3.5.1 Problem Definition</td>\n<td>29</td>\n</tr>\n<tr>\n<td>3.5.2 Technology Development Requirements</td>\n<td>29</td>\n</tr>\n<tr>\n<td>3.5.3 Suggested Approach</td>\n<td>29</td>\n</tr>\n<tr>\n<td>3.5.4 Schedule and Resources</td>\n<td>30</td>\n</tr>\n<tr>\n<td>3.5.5 Verification of Results</td>\n<td>30</td>\n</tr>\n<tr>\n<td>3.5.6 Related Studies</td>\n<td>30</td>\n</tr>\n<tr>\n<td><strong>3.6</strong> AOL Design Guidelines/Standards (TI-06)</td>\n<td>31</td>\n</tr>\n<tr>\n<td>3.6.1 Problem Definition</td>\n<td>31</td>\n</tr>\n<tr>\n<td>3.6.2 Technology Development Requirements</td>\n<td>31</td>\n</tr>\n<tr>\n<td>3.6.3 Suggested Approach</td>\n<td>31</td>\n</tr>\n<tr>\n<td>3.6.4 Schedule and Resources</td>\n<td>31</td>\n</tr>\n<tr>\n<td>3.6.5 Verification of Results</td>\n<td>32</td>\n</tr>\n<tr>\n<td>3.6.6 Related Studies</td>\n<td>32</td>\n</tr>\n<tr>\n<td><strong>3.7</strong> AOL Compiler Generator Cost Factors (TI-07)</td>\n<td>33</td>\n</tr>\n<tr>\n<td>3.7.1 Problem Definition</td>\n<td>33</td>\n</tr>\n<tr>\n<td>3.7.2 Technology Development Requirements</td>\n<td>33</td>\n</tr>\n<tr>\n<td>Section</td>\n<td>Page</td>\n</tr>\n<tr>\n<td>---------</td>\n<td>------</td>\n</tr>\n<tr>\n<td>3.7.3</td>\n<td>Suggested Approach 33</td>\n</tr>\n<tr>\n<td>3.7.4</td>\n<td>Schedule and Resources 34</td>\n</tr>\n<tr>\n<td>3.7.5</td>\n<td>Verification of Results 34</td>\n</tr>\n<tr>\n<td>3.7.6</td>\n<td>Related Studies 34</td>\n</tr>\n<tr>\n<td>3.8</td>\n<td>Interface Criteria for NASA-Distributed Processor Applications (TI-08) 35</td>\n</tr>\n<tr>\n<td>3.8.1</td>\n<td>Problem Definition 35</td>\n</tr>\n<tr>\n<td>3.8.2</td>\n<td>Technology Development Requirements 35</td>\n</tr>\n<tr>\n<td>3.8.3</td>\n<td>Suggested Approach 35</td>\n</tr>\n<tr>\n<td>3.8.4</td>\n<td>Schedule and Resources 36</td>\n</tr>\n<tr>\n<td>3.8.5</td>\n<td>Verification of Results 36</td>\n</tr>\n<tr>\n<td>3.8.6</td>\n<td>Related Studies 36</td>\n</tr>\n<tr>\n<td>3.9</td>\n<td>Task Control Structures for Distributed Processor Environments (TI-09) 37</td>\n</tr>\n<tr>\n<td>3.9.1</td>\n<td>Problem Definition 37</td>\n</tr>\n<tr>\n<td>3.9.2</td>\n<td>Technology Development Requirements 37</td>\n</tr>\n<tr>\n<td>3.9.3</td>\n<td>Suggested Approach 37</td>\n</tr>\n<tr>\n<td>3.9.4</td>\n<td>Schedule and Resources 38</td>\n</tr>\n<tr>\n<td>3.9.5</td>\n<td>Verification of Results 38</td>\n</tr>\n<tr>\n<td>3.9.6</td>\n<td>Related Studies 38</td>\n</tr>\n<tr>\n<td>3.10</td>\n<td>Program Organization Methods for Real-Time Fault Recovery (TI-10) 41</td>\n</tr>\n<tr>\n<td>3.10.1</td>\n<td>Problem Definition 41</td>\n</tr>\n<tr>\n<td>3.10.2</td>\n<td>Technology Development Requirements 41</td>\n</tr>\n<tr>\n<td>3.10.3</td>\n<td>Suggested Approach 41</td>\n</tr>\n<tr>\n<td>3.10.4</td>\n<td>Schedule and Resources 41</td>\n</tr>\n<tr>\n<td>3.10.5</td>\n<td>Verification of Results 42</td>\n</tr>\n<tr>\n<td>3.10.6</td>\n<td>Related Studies 42</td>\n</tr>\n<tr>\n<td>3.11</td>\n<td>Adaptive High-Speed Buffering Techniques for Dynamic Networks (TI-11) 43</td>\n</tr>\n<tr>\n<td>3.11.1</td>\n<td>Problem Definition 43</td>\n</tr>\n<tr>\n<td>3.11.2</td>\n<td>Technology Development Requirements 43</td>\n</tr>\n<tr>\n<td>3.11.3</td>\n<td>Suggested Approach 43</td>\n</tr>\n<tr>\n<td>3.11.4</td>\n<td>Schedule and Resources 44</td>\n</tr>\n<tr>\n<td>3.11.5</td>\n<td>Verification of Results 44</td>\n</tr>\n<tr>\n<td>3.11.6</td>\n<td>Related Studies 44</td>\n</tr>\n<tr>\n<td>Section</td>\n<td>Page</td>\n</tr>\n<tr>\n<td>---------</td>\n<td>------</td>\n</tr>\n<tr>\n<td>3.12 Control Structures for Adaptive Systems (TI-12)</td>\n<td>45</td>\n</tr>\n<tr>\n<td>3.12.1 Problem Definition</td>\n<td>45</td>\n</tr>\n<tr>\n<td>3.12.2 Technology Development Requirements</td>\n<td>45</td>\n</tr>\n<tr>\n<td>3.12.3 Suggested Approach</td>\n<td>45</td>\n</tr>\n<tr>\n<td>3.12.4 Schedule and Resources</td>\n<td>45</td>\n</tr>\n<tr>\n<td>3.12.5 Verification of Results</td>\n<td>46</td>\n</tr>\n<tr>\n<td>3.12.6 Related Studies</td>\n<td>46</td>\n</tr>\n<tr>\n<td>3.13 Impacts of Natural Communication Methods on NASA Payload Systems (TI-13)</td>\n<td>47</td>\n</tr>\n<tr>\n<td>3.13.1 Problem Definition</td>\n<td>47</td>\n</tr>\n<tr>\n<td>3.13.2 Technology Development Requirements</td>\n<td>47</td>\n</tr>\n<tr>\n<td>3.13.3 Suggested Approach</td>\n<td>47</td>\n</tr>\n<tr>\n<td>3.13.4 Schedule and Resources</td>\n<td>48</td>\n</tr>\n<tr>\n<td>3.13.5 Verification of Results</td>\n<td>48</td>\n</tr>\n<tr>\n<td>3.13.6 Related Studies</td>\n<td>48</td>\n</tr>\n<tr>\n<td>3.14 Adaptive Search and Sort Routines (TI-14)</td>\n<td>49</td>\n</tr>\n<tr>\n<td>3.14.1 Problem Definition</td>\n<td>49</td>\n</tr>\n<tr>\n<td>3.14.2 Technology Development Requirements</td>\n<td>49</td>\n</tr>\n<tr>\n<td>3.14.3 Suggested Approach</td>\n<td>49</td>\n</tr>\n<tr>\n<td>3.14.4 Schedule and Resources</td>\n<td>50</td>\n</tr>\n<tr>\n<td>3.14.5 Verification of Results</td>\n<td>50</td>\n</tr>\n<tr>\n<td>3.14.6 Related Studies</td>\n<td>51</td>\n</tr>\n<tr>\n<td>3.15 Restructured Image Analysis Software for Parallel Processing (TI-15)</td>\n<td>53</td>\n</tr>\n<tr>\n<td>3.15.1 Problem Definition</td>\n<td>53</td>\n</tr>\n<tr>\n<td>3.15.2 Technology Development Requirements</td>\n<td>53</td>\n</tr>\n<tr>\n<td>3.15.3 Suggested Approach</td>\n<td>53</td>\n</tr>\n<tr>\n<td>3.15.4 Schedule and Resources</td>\n<td>54</td>\n</tr>\n<tr>\n<td>3.15.5 Verification of Results</td>\n<td>54</td>\n</tr>\n<tr>\n<td>3.15.6 Related Studies</td>\n<td>54</td>\n</tr>\n<tr>\n<td>3.16 Optimal Large Array Partitioning Procedures (TI-16)</td>\n<td>57</td>\n</tr>\n<tr>\n<td>3.16.1 Problem Definition</td>\n<td>57</td>\n</tr>\n<tr>\n<td>3.16.2 Technology Development Requirements</td>\n<td>57</td>\n</tr>\n</tbody>\n</table>\n# TABLE OF CONTENTS\n(Continued)\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>3.16.3 Suggested Approach</td>\n<td>57</td>\n</tr>\n<tr>\n<td>3.16.4 Schedule and Resources</td>\n<td>58</td>\n</tr>\n<tr>\n<td>3.16.5 Verification of Results</td>\n<td>58</td>\n</tr>\n<tr>\n<td>3.16.6 Related Studies</td>\n<td>59</td>\n</tr>\n<tr>\n<td>3.17 Classification of Error Mechanisms (TI-17)</td>\n<td>61</td>\n</tr>\n<tr>\n<td>3.17.1 Problem Definition</td>\n<td>61</td>\n</tr>\n<tr>\n<td>3.17.2 Technology Development Requirements</td>\n<td>61</td>\n</tr>\n<tr>\n<td>3.17.3 Suggested Approach</td>\n<td>61</td>\n</tr>\n<tr>\n<td>3.17.4 Schedule and Resources</td>\n<td>62</td>\n</tr>\n<tr>\n<td>3.17.5 Verification of Results</td>\n<td>62</td>\n</tr>\n<tr>\n<td>3.17.6 Related Studies</td>\n<td>62</td>\n</tr>\n<tr>\n<td>3.18 Guidelines for Design Documentation Consistency (TI-18)</td>\n<td>63</td>\n</tr>\n<tr>\n<td>3.18.1 Problem Definition</td>\n<td>63</td>\n</tr>\n<tr>\n<td>3.18.2 Technology Development Requirements</td>\n<td>63</td>\n</tr>\n<tr>\n<td>3.18.3 Suggested Approach</td>\n<td>63</td>\n</tr>\n<tr>\n<td>3.18.4 Schedule and Resources</td>\n<td>64</td>\n</tr>\n<tr>\n<td>3.18.5 Verification of Results</td>\n<td>64</td>\n</tr>\n<tr>\n<td>3.18.6 Related Studies</td>\n<td>64</td>\n</tr>\n<tr>\n<td>3.19 Software Prototyping Methods (TI-19)</td>\n<td>65</td>\n</tr>\n<tr>\n<td>3.19.1 Problem Definition</td>\n<td>65</td>\n</tr>\n<tr>\n<td>3.19.2 Technology Development Requirements</td>\n<td>65</td>\n</tr>\n<tr>\n<td>3.19.3 Suggested Approach</td>\n<td>65</td>\n</tr>\n<tr>\n<td>3.19.4 Schedule and Resources</td>\n<td>66</td>\n</tr>\n<tr>\n<td>3.19.5 Verification of Results</td>\n<td>66</td>\n</tr>\n<tr>\n<td>3.19.6 Related Studies</td>\n<td>66</td>\n</tr>\n<tr>\n<td>3.20 Software Technology Monitoring (TI-20)</td>\n<td>67</td>\n</tr>\n<tr>\n<td>3.20.1 Problem Definition</td>\n<td>67</td>\n</tr>\n<tr>\n<td>3.20.2 Technology Development Requirements</td>\n<td>67</td>\n</tr>\n<tr>\n<td>3.20.3 Suggested Approach</td>\n<td>67</td>\n</tr>\n<tr>\n<td>3.20.4 Schedule and Resources</td>\n<td>68</td>\n</tr>\n<tr>\n<td>3.20.5 Verification of Results</td>\n<td>68</td>\n</tr>\n<tr>\n<td>3.20.6 Related Studies</td>\n<td>68</td>\n</tr>\n</tbody>\n</table>\nLIST OF FIGURES\n\n<table>\n<thead>\n<tr>\n<th>Figure No.</th>\n<th>Description</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1-1</td>\n<td>Payload Software Technology Study Plan</td>\n<td>2</td>\n</tr>\n<tr>\n<td>2-1</td>\n<td>Technology Driver-Item Correlation Table</td>\n<td>10</td>\n</tr>\n<tr>\n<td>2-2</td>\n<td>Software Technology Item-to-Item Correlation</td>\n<td>12</td>\n</tr>\n<tr>\n<td>2-3</td>\n<td>Technology Item Priority</td>\n<td>14</td>\n</tr>\n<tr>\n<td>2-4</td>\n<td>Priority Evaluation</td>\n<td>16</td>\n</tr>\n</tbody>\n</table>\nINTRODUCTION\n\nThe Software Technology Development Plan is the prime end-item of the basic Payload Software Technology Study (NASA Contract NAS8-32047). This plan was prepared by M&S Computing, Inc., for Mr. John Capps, COR, EF-15, Marshall Space Flight Center. As shown in Figure 1-1, the Software Technology Development Plan was derived from a study composed of three consecutive phases. The purpose of the first phase was to identify software technology drivers. The second phase consisted of a detailed analysis of the technology drivers, from which came a list of potential solutions - Technology Items. Phase III provided a critical assessment of the technology items, in terms of development cost, time and priority. The most promising (or urgent) items were subsequently expanded into individual technology development plans for incorporation into this report.\n\n1.1 Purpose\n\nThe Software Technology Development Plan was formulated to define programmatic requirements for the advancement of Software Technology. The initial study was designed to identify drivers and suggest solutions to meet the requirements of space flight in the 1980-1990 time period, and to project potential technological needs from 1990 through the end of the century.\n\nAll identified software technology requirements were reviewed to establish the following: which requirements can be fulfilled within current state-of-the-art technology; which technology requirements can be developed with a high probability of success and a significant payoff in benefits; and which requirements pose risks (in cost and success) but are considered mandatory for other reasons. The resulting software technology development items are compiled into this development plan. The plan describes justification, cost and schedule, potential payoff benefits, measurable milestones, methods of approach, and methods for verification of results.\n\nA large number of Software Technology Items were identified; however, it does not make sense for NASA to duplicate technology development which is being satisfactorily performed by industry or other government agencies. Therefore, this plan is dedicated to fresh ideas or known items which are not being worked on. Goals have been established by the Outlook For Space (OFS) and the Office of Aeronautics and Space Technology (CAST) Workshops. This plan can only identify the next step toward these goals. Hopefully, it will be a major step.\n\n1.2 Scope\n\nThe primary emphasis in the Software Technology Development Plan is onboard processing in a real-time environment. Payload analysis was based on projected Space Transportation System (STS) payloads as described\nin the July 1975, Shuttle Sortie Payload Description (SSPDA), and from OFS and OAST space technology forecasts. This data was supplemented with an in-depth review of detailed payload studies, Design Reference Mission Analysis (DRM), Integrated Mission Analysis and Planning (IMAP), user's information, previous space programs and studies, and in-house expertise.\n\nThe technology development plans resulting from this study must be implementable during the 1980's in order to meet the requirements in the 1990's. It is assumed, for this study, that the primary development vehicle during this time will be the Space Transportation System. Therefore, payload analyses performed during this study were limited to those payloads currently planned to be carried on the Space Transportation System.\n\nFinally, it should be noted that this study was primarily concerned with software technology; not with computer systems technology. A specific effort has been made to limit the consideration of Technology Items to pure (or near-pure) software technology development. No attempt was made to analyze future Data Management Systems, as a whole, to drive out technology requirements. Such an effort certainly has merit, and might result in software technology requirements; however, many software technology requirements can be identified without an end-to-end data management analysis.\n\n1.3 Organization\n\nThis plan is organized into three sections with three accompanying appendices as summarized in Table 1-1. Section I is standard introductory material and is self-explanatory.\n\nSection II is an executive summary providing an overview of the remainder of the document. It gives a brief summary of the Software Technology Development studies contained in the plan, provides an overall schedule, and identifies any critical sequential or complementary relationships. This section briefly summarizes related technology goals, either in hardware or software items, being pursued elsewhere. It also lists the priority relationships existing so that the plan can easily be adjusted to varying budgetary conditions.\n\nSection III gives a detailed description of each selected Software Technology Development study. Each Software Technology Development Item is allocated a subsection. Each subsection describes the causes leading to the technology need, and relates the problem to the supporting data accumulated during Phases I and II of this study. It defines the magnitude of potential cost or performance benefits, as well as a summary of the anticipated costs of associated technology development.\nThis section also describes the apparent technological solutions and associated technology development requirement(s). Associated hardware or systems technology items are described to ensure that all facets of the problem, as well as its solution, are clarified. Next, the potential approach that is likely to accomplish the stated technological objective is outlined. Subsequently, schedules and resources required to accomplish this particular technological development item are identified. Available means of intermediate and final measurable verification of the results associated with this item are listed.\n\nThe appendices provide a description of the technology requirements from which the Technology Development Studies were selected. The technology requirements are also related to the experiments from which they were derived wherever relevant.\nPHASE III REPORT OUTLINE\n\nSOFTWARE TECHNOLOGY DEVELOPMENT PLAN\n\nSECTION I - INTRODUCTION - This section describes the purpose of this plan, the scope of the plan, and the manner in which the plan is organized.\n\nSECTION II - SUMMARY - This section is an executive summary of the Software Technology Development Plan and its derivation.\n\nSECTION III - DESCRIPTION OF SOFTWARE TECHNOLOGY ITEMS - This section is the description and planned approach to each of the Software Technology Development studies selected.\n\n3.1 Item TI-01\n\n3. n Item TI-n\n\nAPPENDIX A - Technology Driver Derivation\n\nAPPENDIX B - Software Technology Item Derivation Worksheets\n\nAPPENDIX C - Cost/Time/Priority Assessment\n\nTable 1-1\n1.4 References\n\nA thorough survey was made of current literature as well as government, industry, and other publications relating to software technology. The prime forecasting references used in this study are as follows:\n\n- Space Electronics Technology Summary, March 1976.\n- Findings and Recommendations of the Joint Logistics Commanders Software Reliability Work Group, November 1975.\n- Software Technology Present and Future, Bobby Hodges, 14th Annual Southeast Regional ACM Conference, April 1976.\n2. SUMMARY\n\nThis section provides a top-level view of the Software Technology Items identified in the study, a composite development schedule, relationship to other technology developments and an identification of development priorities. The Software Technology Items described in this section were selected in order to support efforts to:\n\n- Reduce the high cost of meeting flight software reliability requirements.\n- Remove limitations on data compression and information extraction techniques.\n- Increase the capacity of space-to-earth communication links.\n- Meet the requirements for human control of complex instruments and remote systems.\n- Simplify, reduce the cost of and make usable complex software systems.\n\n2.1 Description of Software Technology Development Items\n\nPhase I of this study concentrated on evaluation of the processing requirements (sizing, speed, input/output rates, etc.) of representative space missions, primarily Spacelab, anticipated for the coming decade. This part of the study provided the basis for selecting drivers of software technology. Consistent with expectations, problems were not peculiar to specific missions, instruments or applications; they were common to many classes of missions, instruments, and applications. Software technology advancements do not just require a new algorithm or unique approach to a given problem. Software technology advancement needs tend to fall in broad, general improvement categories as follows:\n\n- Methods for containing, controlling, and reducing data rate and volume.\n- Methods of improving information content.\n- Techniques to reduce cost of software development.\n- Techniques for improving software reliability and simplifying verification/validation activity.\nTechniques to capitalize on the potential offered by breakthroughs in hardware technology.\n\nKnowledge of how to use the new hardware technology.\n\nThe problems and needs thus identified were thoroughly assessed and compiled into a list of fifteen Software Technology Drivers as shown in Table 2-I and described in Appendix A. The Technology Drivers associated with Software Development must be considered the most important. Unless significant improvements are made in this area, all other related technologies will be stunted because the associated software will be too costly and/or too unreliable. In Software Systems Architecture, most of the Technology Drivers are related to LSI technology; i.e., the availability of very low-cost processing systems. These systems are particularly suitable for onboard usage and therefore receive significant emphasis. The remaining Technology Drivers are primarily based on anticipated increases in onboard processing of image type data, as well as on anticipated increases in the rates of data to be acquired.\n\nIn Phase II of the study, the fifteen Software Technology Drivers were analyzed in detail in search of potential solutions to the problems posed. This analysis resulted in identification of over sixty Software Technology Items. Twenty of these were determined to require forced advancement by NASA if current NASA plans are to be met. The twenty Software Technology Items are shown in Figure 2-1 as related to the Technology Drivers from which they were derived. (Blocks containing asterisks represent relationships established during Technology Development Analysis activities of Phase III. Asterisks in the TI-19 row indicate secondary benefits that may be derived from use of software prototyping.)\n\nThe total number of Technology Items identified may be impossible to implement within the resource constraints. Therefore, during Phase III, cost estimates and priorities were assigned to the twenty Technology Items. The result is a recommended set of Software Technology Development Plans. These were obtained through evaluation and selection of the most cost effective set of Technology Items. The interrelationship of the Technology Items and dependencies on other technologies are as described in the remainder of Section 2.\nTECHNOLOGY DRIVER SUMMARY\n\nSOFTWARE DEVELOPMENT\n\n- SOFTWARE DESIGN ENGINEERING\n- TREND TOWARD S/W DEVELOPMENT BY NON-PROGRAMMERS\n- FAULT-FREE SOFTWARE\n- APPLICATION-ORIENTED LANGUAGE DESIGN METHODOLOGY\n- LOST COST DEVELOPMENT OF AOL COMPILERS\n\nSOFTWARE SYSTEMS ARCHITECTURE\n\n- (DISTRIBUTED) SYSTEM PARTITIONING/INTERCONNECTION TECHNIQUES\n- VERY LARGE STORAGE ACCESS SIMPLIFICATION\n- SOFTWARE FAULT (OWN OR INDUCED) DETECTION\n- SOFTWARE RECOVERY (AFTER FAULT DETECTION)\n- HIGH-SPEED BUFFERING TECHNIQUES\n- DESIGN AND CONTROL OF ADAPTIVE SOFTWARE PROCEDURES\n- USE OF \"NATURAL\" COMMUNICATION METHODS\n- EFFICIENT LARGE ARRAY SEARCH AND SORT PROCEDURES\n- PARALLEL PROCESSING TECHNIQUES\n- EFFICIENT LARGE ARRAY MANIPULATION PROCEDURES\n\nTable 2-1\n<table>\n<thead>\n<tr>\n<th>TI NO.</th>\n<th>SOFTWARE TECHNOLOGY ITEM</th>\n<th>SOFTWARE TECHNOLOGY DRIVER: PS-</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>REQUIREMENTS DECOMPOSITION AND STRUCTURING GUIDELINES</td>\n<td>1 2 3 4 5 6 7 8 9 10 11 12 13 14 15</td>\n</tr>\n<tr>\n<td>2</td>\n<td>REQUIREMENTS-TO-CODE TRANSLATION AIDS</td>\n<td></td>\n</tr>\n<tr>\n<td>3</td>\n<td>SIMPLIFIED SOFTWARE DEVELOPMENT SYSTEM DEMONSTRATION MODEL</td>\n<td></td>\n</tr>\n<tr>\n<td>4</td>\n<td>QUERY-GUIDED IMPLEMENTATION METHODS</td>\n<td></td>\n</tr>\n<tr>\n<td>5</td>\n<td>STANDARDIZATION CRITERIA FOR NASA SOFTWARE</td>\n<td></td>\n</tr>\n<tr>\n<td>6</td>\n<td>AOL DESIGN GUIDELINES/STANDARDS</td>\n<td></td>\n</tr>\n<tr>\n<td>7</td>\n<td>AOL COMPILER GENERATOR COST FACTORS</td>\n<td></td>\n</tr>\n<tr>\n<td>8</td>\n<td>INTERFACE CRITERIA FOR NASA DISTRIBUTED PROCESSOR APPLICATIONS</td>\n<td></td>\n</tr>\n<tr>\n<td>9</td>\n<td>TASK CONTROL STRUCTURES FOR DISTRIBUTED PROCESSOR ENVIRONMENTS</td>\n<td></td>\n</tr>\n<tr>\n<td>10</td>\n<td>PROGRAM ORGANIZATION METHODS FOR REAL-TIME FAULT RECOVERY</td>\n<td></td>\n</tr>\n<tr>\n<td>11</td>\n<td>ADAPTIVE HIGH SPEED BUFFERING TECHNIQUES FOR DYNAMIC NETWORKS</td>\n<td></td>\n</tr>\n<tr>\n<td>12</td>\n<td>CONTROL STRUCTURES FOR ADAPTIVE SYSTEMS</td>\n<td></td>\n</tr>\n<tr>\n<td>13</td>\n<td>IMPACTS OF NATURAL COMMUNICATION METHODS ON NASA PAYLOAD SYSTEMS</td>\n<td></td>\n</tr>\n<tr>\n<td>14</td>\n<td>ADAPTIVE SEARCH AND SORT PROCEDURES</td>\n<td></td>\n</tr>\n<tr>\n<td>15</td>\n<td>RESTRUCTURED IMAGE ANALYSIS SOFTWARE FOR PARALLEL PROCESSING</td>\n<td></td>\n</tr>\n<tr>\n<td>16</td>\n<td>OPTIMAL LARGE ARRAY PARTITIONING PROCEDURES</td>\n<td></td>\n</tr>\n<tr>\n<td>17</td>\n<td>CLASSIFICATION OF ERROR MECHANISMS</td>\n<td></td>\n</tr>\n<tr>\n<td>18</td>\n<td>GUIDELINES FOR DESIGN DOCUMENTATION CONSISTENCY</td>\n<td></td>\n</tr>\n<tr>\n<td>19</td>\n<td>SOFTWARE PROTOTYPING METHODS</td>\n<td>* * * * * * * * * * * * * * * *</td>\n</tr>\n<tr>\n<td>20</td>\n<td>SOFTWARE TECHNOLOGY MONITORING</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nFigure 2-1\nAnalysis of the Software Technology Items resulted in the selection of seven which represent the highest priority and are most apt to result in the earliest return of appreciable benefits. These are:\n\n- TI-01 Requirements Decomposition and Structuring Guidelines.\n- TI-08 Interface Criteria for NASA Distributed Processor Applications.\n- TI-09 Task Control Structures for Distributed Processor Environments.\n- TI-10 Program Organization Methods for Real-Time Fault Recovery.\n- TI-15 Restructured Image Analysis Software for Parallel Processing.\n- TI-17 Classification of Error Mechanisms.\n- TI-20 Software Technology Monitoring.\n\nThe first five items are very specific and are directed to the major goals of reducing cost, enhancing or enabling functions, improving reliability and reducing the raw data flow. The last two items are more general in nature. TI-20, Software Technology Monitoring can and most likely will result in significant contributions to all major goals. TI-17 could very well be considered a subset of TI-20.\n\n2.2 Relation to Other Technology Development\n\nDependencies exist between variable independent Technology Items. Solution of a problem posed by a Technology Driver requires the full consideration of the interrelationships between these variables as well as the direct relationship to a specific item. This interrelationship is shown in the Item-to-Item correlation matrix of Figure 2-2. In this chart relationships are shown which do not necessarily appear in the Driver-Item matrix, because secondary relationships are identified wherever possible. The primary goal of this chart is to aid in establishing the overall technology Development Schedule described in Section 2.4.\n\nOther software technology development activities are either underway or have been proposed, both within and outside NASA. The more significant of these are discussed in the Software Technology Item Derivation Worksheets (Appendix B).\n| | TI-01 | TI-02 | TI-03 | TI-04 | TI-05 | TI-06 | TI-07 | TI-08 | TI-09 | TI-10 | TI-11 | TI-12 | TI-13 | TI-14 | TI-15 | TI-16 | TI-17 | TI-18 | TI-19 | TI-20 |\n|-----|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|\n| TI-01 | X X X | X | | | | | | | | | | | | | | | | | |\n| TI-02 | X | | | | | | | | | | | | | | | | | | |\n| TI-03 | | | | | | | | | | | | | | | | | | | |\n| TI-04 | | | | | | | | | | | | | | | | | | | |\n| TI-05 | | | | | | | | | | | | | | | | | | | |\n| TI-06 | | | | | | | | | | | | | | | | | | | |\n| TI-07 | | | | | | | | | | | | | | | | | | | |\n| TI-08 | | | | | | | | | | | | | | | | | | | |\n| TI-09 | | | | | | | | | | | | | | | | | | | |\n| TI-10 | | | | | | | | | | | | | | | | | | | |\n| TI-11 | | | | | | | | | | | | | | | | | | | |\n| TI-12 | | | | | | | | | | | | | | | | | | | |\n| TI-13 | | | | | | | | | | | | | | | | | | | |\n| TI-14 | | | | | | | | | | | | | | | | | | | |\n| TI-15 | | | | | | | | | | | | | | | | | | | |\n| TI-16 | | | | | | | | | | | | | | | | | | | |\n| TI-17 | | | | | | | | | | | | | | | | | | | |\n| TI-18 | | | | | | | | | | | | | | | | | | | |\n| TI-19 | | | | | | | | | | | | | | | | | | | |\n| TI-20 | X X X | X | | | | | | | | | | | | | | | | | |\n\nFigure 2-2\n2.3 Identification of Priorities\n\nMany factors were involved in setting the priorities of the candidate Software Technology Items. Once the initial step of identifying a problem was completed, the next step was to evaluate the current and estimated state of the art in the associated technology area. This evaluation is reflected in Appendix C, the Cost/Time/Priority Assessment. The levels established were based on the following criteria:\n\n1 - Basic principles observed and reported.\n2 - Conceptual design formulated.\n3 - Conceptual design tested analytically or experimentally.\n4 - Critical function/characteristic demonstrated.\n5 - Component/section tested/reviewed in relevant environment.\n6 - Prototype/draft tested/reviewed in relevant environment.\n7 - Final product tested in operational/space environment.\n8 - New capability derived from a much lesser operational model.\n9 - Reliability upgrading of an operational model.\n\nThese state-of-the-art levels were not used for setting priorities per se, but were used as aids to help determine whether appropriate advancement could be achieved by industry alone, or if NASA participation would be required.\n\nIn order to facilitate setting priorities, attain consistency, and limit subjectivity, a logic flow was developed as shown in Figure 2-3. This flow embodied the major elements of priority assignment and resulted in a rating of 0-6 for each technology item. The elements used were:\n\n- Enablement.\n- Cost Reduction.\n- Enhancement.\n\nEnablement was subdivided into two categories, critical and desirable. (Initially, enablement was divided into mandatory and desirable, but as it became evident that none of the items would actually preclude a space mission, the mandatory rating was downgraded to critical).\nTECHNOLOGY ITEM PRIORITY\n\n**Figure 2-3**\n\n- **TECHNOLOGY ITEM**\n - PRIORITY EQUAL\n - 6\n - ENABLEMENT\n - NO\n - PRIORITY = -3\n - COST REDUCTION\n - NO\n - PRIORITY = -3\n - ENHANCEMENT\n - NO\n - PRIORITY = +1\n - CRITICAL\n - NO\n - PRIORITY = -2\n - ENHANCEMENT\n - NO\n - PRIORITY = +1\n - OR\n - SORT BY RETURN-COST\n - OR\n - SORT BY DATE\n - WITHIN COST RANGE\n - REJECT\n - 0\n - 1\n - 2\n - 3\n - 4\n - 5\n - 6\n - YES\n - ENHANCEMENT\n - YES\n - PRIORITY = +1\n - OR\n - SORT BY COST\n - OR\n - SORT BY DATE WITHIN COST RANGE\n - REJECT\n - 0\n - 1\n - 2\n - 3\n - 4\n - 5\n - 6\n - YES\n - ENHANCEMENT\n - NO\n - PRIORITY = +1\n - OR\n - SORT BY COST\n - OR\n - SORT BY DATE WITHIN COST RANGE\n - REJECT\n - 0\n - 1\n - 2\n - 3\n - 4\n - 5\n - 6\n - YES\n - ENHANCEMENT\n - NO\n - PRIORITY = +1\n - OR\n - SORT BY COST\n - OR\n - SORT BY DATE WITHIN COST RANGE\n - REJECT\n - 0\n - 1\n - 2\n - 3\n - 4\n - 5\n - 6\n - YES\n - CRITICAL\n - NO\n - PRIORITY = -2\n - OR\n - SORT BY RETURN-COST\n - OR\n - SORT BY DATE\n - WITHIN COST RANGE\n - REJECT\n - 0\n - 1\n - 2\n - 3\n - 4\n - 5\n - 6\n - YES\n - CRITICAL\n - YES\n - PRIORITY = -2\n - OR\n - SORT BY RETURN-COST\n - OR\n - SORT BY DATE\n - WITHIN COST RANGE\n - REJECT\n - 0\n - 1\n - 2\n - 3\n - 4\n - 5\n - 6\n - YES\n - CRITICAL\n - YES\n - PRIORITY = +1\n - OR\n - SORT BY RETURN-COST\n - OR\n - SORT BY DATE\n - WITHIN COST RANGE\n - REJECT\n - 0\n - 1\n - 2\n - 3\n - 4\n - 5\n - 6\nCritical enablement describes an item which could gravely affect the achievement of a major NASA objective (e.g., 1000x data at 1/10th cost) if it were not resolved. Critical enablement was given a weight of 6. Desirable enablement describes a technology that would enable a new function to be performed, or allow additional experimentation with a given instrument, that would significantly increase the return benefit of a payload. Desirable enablement was equated in value to enhancement, and thus given a weight of 1.\n\nCost reduction applies to those software items which could have major effect on the cost of space activity in general. Most of these items fall in the category of Software Engineering or Software Development. Cost reduction was given a weight of 3.\n\nEnhancement applies to those items that would enhance the total information gathering and distribution process. This includes improved reliability, more effective processing, higher quality data recovery, and other advancements that would be highly beneficial. Enhancement was given a weight of 1.\n\nAfter the initial assessment, other factors (Drivers affected and Cost/Benefit Returns) were added in. A value of 1 was added to each Technology Item for every Driver upon which it had a primary effect. The Cost/Benefit Return was given a rating of high, medium or low, and equated to a weight of 2 for high, 1 for medium and 0 for low. (Note: Need dates were determined not to be significant factors for these Technology Items.)\n\nThe priority factors were then summed for each Software Technology Item to derive an overall rating as shown in the priority evaluation chart in Figure 2-4. The Technology Items identified with an asterisk are those that fall in the top third of the overall ratings, and thus are those recommended for immediate NASA consideration.\n\n2.4 Development Schedule\n\nA schedule for the development or advancement of technology required by each of the selected Software Technology Items is contained within each Technology Development Plan. In general, each item is given a 1978 start date, as most of them are immediately necessary with the advent of the STS operational phase in 1980 and each will require a year or more to complete.\n\nFor planning purposes it was assumed that development of an operational application would take two years after demonstration of a\n### PRIORITY EVALUATION\n\n<table>\n<thead>\n<tr>\n<th>TI No.</th>\n<th>Critical Enablement</th>\n<th>Desirable Enablement</th>\n<th>Cost Reduction</th>\n<th>Enhancement</th>\n<th>Priority</th>\n<th>Applicable Drivers</th>\n<th>Cost/Benefit Return</th>\n<th>Need Date</th>\n<th>Rating</th>\n<th>Top 1/3</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>01</td>\n<td></td>\n<td>X</td>\n<td>X</td>\n<td>X</td>\n<td>5</td>\n<td>3</td>\n<td>1</td>\n<td>0</td>\n<td>N/A</td>\n<td>9</td>\n</tr>\n<tr>\n<td>02</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td>X</td>\n<td>3</td>\n<td>1</td>\n<td>1</td>\n<td>1</td>\n<td>N/A</td>\n<td>4</td>\n</tr>\n<tr>\n<td>03</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>3</td>\n<td>1</td>\n<td>0</td>\n<td>0</td>\n<td>N/A</td>\n<td>5</td>\n</tr>\n<tr>\n<td>04</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>3</td>\n<td>1</td>\n<td>0</td>\n<td>2</td>\n<td>N/A</td>\n<td>4</td>\n</tr>\n<tr>\n<td>05</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td>X</td>\n<td>4</td>\n<td>1</td>\n<td>2</td>\n<td>3</td>\n<td>N/A</td>\n<td>7</td>\n</tr>\n<tr>\n<td>06</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>3</td>\n<td>1</td>\n<td>0</td>\n<td>4</td>\n<td>N/A</td>\n<td>4</td>\n</tr>\n<tr>\n<td>07</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>3</td>\n<td>1</td>\n<td>0</td>\n<td>4</td>\n<td>N/A</td>\n<td>4</td>\n</tr>\n<tr>\n<td>08</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>3</td>\n<td>1</td>\n<td>0</td>\n<td>4</td>\n<td>N/A</td>\n<td>4</td>\n</tr>\n<tr>\n<td>09</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>2</td>\n<td>5</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>10</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>3</td>\n<td>1</td>\n<td>6</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>11</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>0</td>\n<td>7</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>12</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>1</td>\n<td>8</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>13</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>0</td>\n<td>9</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>14</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>0</td>\n<td>10</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>15</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>1</td>\n<td>11</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>16</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>2</td>\n<td>12</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>17</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>1</td>\n<td>13</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>18</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>0</td>\n<td>14</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>19</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>1</td>\n<td>15</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n<tr>\n<td>20</td>\n<td></td>\n<td>X</td>\n<td></td>\n<td></td>\n<td>5</td>\n<td>2</td>\n<td>2</td>\n<td>16</td>\n<td>N/A</td>\n<td>8</td>\n</tr>\n</tbody>\n</table>\n\n*Figure 2-4*\nprototype model. For instance, an image processing application needed in 1985 would have to be proven feasible by 1983 in order to allow time for development of a flight item.\n\nIn any event, the benefits that will accrue from the development of any Technology Item cannot begin until the development is complete.\n3. SOFTWARE TECHNOLOGY ITEM DEVELOPMENT PLANS\n\n3.1 Requirements Decomposition and Structuring Guidelines (TI-01)\n\n3.1.1 Problem Definition\n\nSoftware design practice up to now has suffered from a lack of consistency among designers in their approach to decomposition of the requirements and development of design structure. The need for rational guidelines becomes apparent when one considers the fact that totally different designs can result from different designers working on identical software requirements. This makes it almost impossible to evaluate designs, much less to identify the optimum design. Unlike hardware, in which standard components are integrated by well-established logic principles, each software design is a new design. This is costly in development and implementation, but even more so in the training and maintenance requirements to support utilization phases of an operational system.\n\nOf even more importance, lack of consistent, good design compromises the most valuable characteristic of software -- the flexibility to adapt to changing requirements. The study proposed to help solve this basic Software Engineering problem is expected to be of moderate cost (3-10 man years).\n\n3.1.2 Technology Development Requirements\n\nThe technology developments needed under this broad-based study are the guidelines for requirements decomposition and structuring in software design. These developments must contribute towards achieving consistency in design. Also, it is necessary to derive and establish proper design evaluation criteria.\n\nTechnology must be developed which will provide a means to convey what the requirements are, and will allow the breakdown of these requirements into a functional distribution. This should lead to software designs that are reliable and easily understood, implemented, used, and maintained.\n\n3.1.3 Suggested Approach\n\nThe study proposed for this effort has four steps as shown under the schedule. The first step is the establishment of requirements decomposition guidelines. A comprehensive set of guidelines for decomposition of the furnished software requirements is to be developed. This will be done through a thorough review of the various current approaches to the problem and a critical analysis of the relative advantages and disadvantages of these approaches. The next step is to develop a logical set of guidelines\naimed at achieving consistency of design across a given set of requirements. This must be followed by the establishment of techniques which will ensure proper structuring of functions into a viable, usable design. Development of guides to proper structure and consistent design is an iterative enhancement process, as shown in the schedule. In parallel with the previous activity, the criteria for measurement and evaluation of design products will be established. This will be of considerable significance in assessing the results of using these guidelines in NASA applications.\n\n3.1.4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>• Requirements Decomposition Guidelines.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>• Design Consistency Guidelines.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>• Structuring Guidelines.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>• Evaluation Criteria.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated Cost of Development: $150K - 500K.\n\n3.1.5 Verification of Results\n\nThe end product of this effort will be a set of guidelines for software design rather than a specific piece of software. The verification of results can be viewed as the assessment of benefits arising from application of these guidelines. Thus, this step in effect consists of applying these guidelines to one or more specific software design efforts to compare the experience with similar efforts not based on these guidelines. The relative merit will be assessed through application of the evaluation criteria, which in turn can be appraised through demonstration of actual program product results. The verification process itself will make a valuable contribution to the development of the Software Engineering profession.\n\n3.1.6 Related Studies\n\n- Software Technology Items.\n - TI-08 Interface criteria for NASA distributed processor applications.\n - TI-09 Task control structures for distributed processor environments.\n- TI-18 Guidelines for design documentation consistency.\n\n- TI-19 Software prototyping methods.\n\n- Software Technology Items (Secondary).\n\n- TI-10 Program organization methods for real-time fault recovery.\n\n- TI-15 Restructured image analysis software for parallel processing.\n3.2 Requirements-to-Code Translation Aids (TI-02)\n\n3.2.1 Problem Definition\n\nCurrent practice of manual generation of codes from given software requirements is not only expensive but also error-prone. This is because, first, the software requirements are not specified in a standard format and hence the requirements decomposition is mostly ad hoc. Second, the lack of consistent design guidelines makes the steps leading to the generation of codes more of an art (or lack of it!) rather than a science. Therefore, for a given set of requirements the generated code does not necessarily reflect the best code, and methods of proving the software as fault-free are still to be realized. Therefore, some means of automating the code generation process is essential to achieve a measure of error and cost control in software development. This requirement-to-code translation problem is likely to be of relatively high cost and require 10-20 man years.\n\n3.2.2 Technology Development Requirements\n\nThe requirements under this study are defined as the development of automated aids for generating program codes (in a desired language) from a specified set of software requirements. This technology development is tailored to meet the specific needs of payload software requirements, rather than any general study of automatic programming, to ensure direct payoff for NASA for its investment in this technology development effort.\n\n3.2.3 Suggested Approach\n\nThe first step of this study is a review and assessment of the on-going efforts in this field as applied to other areas of software development, particularly business-oriented and other commercially funded projects. In parallel with this, a requirements analysis must be carried out to identify the spectrum of NASA payload software needs. With these preliminary efforts as the base, a master software instructions/code library, consisting of all the key functions reflecting NASA payload software requirements, can be developed. The next step is to define and develop a transformational approach which can successively transform, in stages, the input software requirements into a set of program codes using the master library as a reference. The developed methodology is then tested and the related documentation prepared to ensure its suitability for application to NASA payload software development.\n3.2.4 Schedule and Resources\n\n- Analyze requirements.\n- Identify the spectrum of NASA payload software requirements.\n- Develop a master software instruction code library consisting of all basic functions reflecting NASA payload software requirements.\n- Develop a transformational approach which transforms the input requirements successively into a set of program codes using the library.\n- Test and document the methodology developed.\n\nEstimated cost of development: $500K - $1000K. Resources include access to information on future payload software development plans and program details.\n\n3.2.5 Verification of Results\n\nThe developed requirement-to-code translation aids will be test-implemented and validated as to their ability to perform the designated function. The testing will include actual application of the code generator product to a previous software implementation to derive and compare the operational capability of the automatically generated code with the earlier manually developed code.\n\n3.2.6 Related Studies\n\n- Software Technology Items.\n - TI-01 Requirements decomposition and structuring guidelines.\n - TI-03 Simplified software development system demonstration model.\n - TI-04 Query-guided implementation methods.\n - TI-18 Classification of error mechanisms.\n - TI-19 Software prototyping methods.\n3.3 Simplified Development System Demonstration Model (TI-03)\n\n3.3.1 Problem Definition\n\nThe advent of large scale usage of microprocessors in distributed systems for real-time space applications calls for simpler software development tools. This is necessary to ensure that the cost of software development will not become a barrier to the benefits of microprocessor usage which otherwise is very cost-effective.\n\nMany software development systems exist, but it is rare to find one that is simple and even rarer to find one that is transportable. In an era of diverse users of space systems, each developing a software subset of a future integrated flight complement, ways and means of simply and economically developing software components must be found.\n\nAn effort which is designed to achieve this objective is the creation of a demonstration model of a simplified system for software development. This effort can be expected to be one of relatively high cost requiring 10-20 man years.\n\n3.3.2 Technology Development Requirements\n\nThe feasibility of a simplified system for software development can be shown by the creation of an appropriate demonstration model. Accordingly, the technology requirements of the study can be stated as the building of a simplified development system demonstration model. This will be a precursor to low-cost operational systems for use by non-professional programmers in the development of space applications.\n\n3.3.3 Suggested Approach\n\nThis development effort has several identifiable steps as shown in the schedule. The first step is the requirements definition. Requirements definition is based on developing a clear understanding of the purpose of the model and the environmental constraints under which the modeled system will have to operate. These requirements are analyzed to derive the specifications of the demonstration model. This is followed by the design of the demonstration model which will emphasize the different aspects of the operational system envisioned for the PI's use. The design phase leads to the development and test phase which in turn takes the project to the final detailed system evaluation phase. The final evaluation phase is a key element. It must be detailed enough to ensure that the follow-on work of developing an operational system can be taken up with confidence that the end product will support the anticipated heavy schedule of software development in the coming decade.\n3.3.4 Schedule and Resources\n\n- Requirements Definition.\n- Requirements Analysis\n- Demonstration Model System Design.\n- Development and Test.\n- Evaluation.\n\nEstimated cost of development: $500K - $1000K.\n\n3.3.5 Verification of Results\n\nThe evaluation of the demonstration model and its effectiveness is a significant part of the effort to be accomplished under this study. The schedule allows a full year for this activity and effectively portrays the importance given to this phase of the effort. This is essential to ensure the integrity of the demonstration model and the operational system to follow. Each step of the effort provides concrete output products (i.e., requirements, composition, design specifications, test system and evaluation system) for measurable verification of progress.\n\n3.3.6 Related Studies\n\n- Software Technology Items.\n - TI-02 Requirements-to-code translation aids.\n - TI-04 Query-guided implementation methods.\n - TI-17 Classification of error mechanisms.\n - TI-19 Software prototyping methods.\n3.4 Query-Guided Implementation Methods (TI-04)\n\n3.4.1 Problem Definition\n\nThe objective of this technology item is the development of new programming procedures wherein the programming effort is supported/guided by a questionnaire. The basic problem to be addressed is essentially similar to the one underlying TI-02, Requirements-to-Code Translation Aids, in that new automated tools for software development are called for to reduce the expensive, error prone manual approach to code generation. However, the emphasis here is less on autonomy than in the other approach and presumably the objectives are more easily realizable. This effort is consequently more moderate in cost (5-10 man years) and is expected to result in a faster return of benefits.\n\n3.4.2 Technology Development Requirements\n\nTechnology development required under this study are semi-automated tools for software development using the questionnaire approach. This questionnaire approach must be especially attractive for interactive man-machine systems, operating in dynamic environments, wherein it may be necessary to create new software and/or new configurations of existing software. Query-guided implementation methods must offer the flexibility necessary for such applications. At the same time these methods must contribute towards the traditional software development goals in terms of reduced software errors and consistency in the quality of the resulting software product.\n\n3.4.3 Suggested Approach\n\nAs a practical step, it is advisable to constrain this effort of the development of semi-automated tools to the specific NASA payload software development requirements. This limitation ensures that a viable solution will be developed within the time and cost constraints of NASA programs. Any attempt at global solutions could lead to lack of effective control over the projected costs and time schedules. The first step is, therefore, to develop and establish the common features and requirements of NASA payload software development programs. This is to be followed by an effort directed towards developing a skeleton structure of the software corresponding to established commonalities. The next step is the design and development of a questionnaire methodology which when applied to specific requirements leads to the filling out of the skeleton structure and results in the desired software package. Finally, the methodology should be thoroughly tested and documented to ensure an appropriate return on investment for NASA.\n\n-27-\n3.4.4 Schedules and Resources\n\n- Derive and establish the common features of NASA payload programs.\n- Develop a skeleton structure of the development system.\n- Develop a questionnaire methodology for filling out the skeleton structure.\n- Test and document the methodology.\n\nEstimated development costs: $200K - $500K\n\n3.4.5 Verification of Results\n\nThe end product of the study being implementable methodology, it is necessary to ensure that the developed tools can be put to effective use through testing and documentation. This testing should include test implementation in specific NASA software development programs to evaluate its effects on efficiency, reliability and cost of program development. In view of the man-machine interaction involved in questionnaire approaches, it is desirable to study programmer responses to the methodology as part of the verification process to ensure its acceptability.\n\n3.4.6 Related Studies\n\n- Software Technology Items.\n - TI-02 Requirements-to-code translation aids.\n - TI-03 Simplified software development system demonstration mode.\n - TI-18 Classification of error mechanism.\n - TI-19 Software prototyping methods.\n3.5 Standardization Criteria for NASA Software (TI-05)\n\n3.5.1 Problem Definition\n\nLack of standardization in software design, development, testing and other facets of software projects, even within the bounded sphere of NASA activities, frequently results in expensive, often duplicated software. Needed reliability is difficult to achieve. Standardized software can make a significant contribution towards the goal of totally fault-free software. Therefore, as a first step, it is necessary to develop the criteria for standardization. The degree of the problem solution depends on the scope of the standardization process; however, as proposed here is expected to be of moderate cost involving 3-10 man years of effort.\n\n3.5.2 Technology Development Requirements\n\nDevelopment of standardization criteria is the goal of this technology development item. This criteria development will span the spectrum of activities associated with a software development project. For example, standardization has many implications: standard language design, standard operating system design, and standard interface implementation. A degree of standardization in each of these areas and criteria for such standardization is desired and sought under this effort.\n\n3.5.3 Suggested Approach\n\nThe first step must be to understand and analyze the implications of standardization. Through this effort, it should be possible to identify the specific elements of a software project which can be considered prime candidates for standardization. Once the areas deemed feasible for standardization are established, the next logical step is to develop the criteria for standardization.\n\nIt is advisable to gain some insight into industry practices in standardization and apply these ideas with necessary modifications to the NASA environment. Modification and possibly new concepts may be necessary in view of (1) the decentralized nature of the NASA organization (and the diversified contractor force supporting it), (2) the consequent problems of coordinating the software development efforts, and (3) the difficulties in enforcing the standardization procedures. Selected candidate software packages should be weighed and tested against the developed standardization criteria to validate their effectiveness in establishing standard NASA software libraries for the 1980-1990 time frames.\nNew developments in software design methodology which might influence the standardization criteria are conceivable and modifications at a later date may have to be made. However, irrespective of such future changes, it is necessary to have fairly rigid standardization criteria to avoid duplication of efforts and minimize the software development costs and associated errors.\n\n3.5.4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Tasks</td>\n<td>Analysis of Standardization Implications</td>\n<td>Development of Criteria</td>\n<td>Identification of Candidates</td>\n<td>Evaluation of Validity</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated cost of development: $150K - $500K.\nResource requirements include NASA-wide access to software projects, programs and present practices for minimizing duplication of efforts.\n\n3.5.5 Verification of Results\n\nThe end product of this study is a set of standardization criteria. The verification process essentially consists of applying the criteria to selected software packages and development projects to determine the validity and feasibility of enforcing such criteria in the development process.\n\n3.5.6 Related Studies\n\nThis Technology Item is pertinent to virtually every aspect of the computer software domain.\n3. 6 \\textbf{AOL Design Guidelines/Standards (TI-06)}\n\n3. 6. 1 Problem Definition\n\nApplication-oriented languages (AOL) are expected to dominate the scene in future decades with users developing the software required for their particular needs. This requires appropriate AOL design guidelines and standards to ensure that the AOL's developed to meet the needs of a changing environment are compatible with NASA system goals and have the requisite language consistency. This developmental effort is expected to be one of relatively modest cost involving 2-5 man years.\n\n3. 6. 2 Technology Development Requirements\n\nDevelopment of design guidelines and standards for application-oriented languages (of interest to NASA applications) is the technology advancement required by this item. This requirement is the first step towards the goals of economical development of efficient application-oriented languages, particularly those of real-time onboard distributed systems. Design guidelines/standards are to ensure that the resulting AOL's are simple to use and efficient even when deployed by non-professional programmers. These requirements tie this effort to the one proposed in the next item (TI-07) on AOL compiler generator cost factors. The AOL design guidelines will determine the complexity of the compilers and therefore influence the cost of generating these compilers. Accordingly, the developments under this study have in view the objectives and associated factors of TI-07.\n\n3. 6. 3 Suggested Approach\n\nAs illustrated in the schedule, the approach consists of three specific steps. The first is the determination of the concepts underlying AOL and understanding what its requirements are. These concepts are an essential prerequisite to the development of guidelines for AOL design. The next step is the actual development of guidelines to meet the requirements as derived. The third step is the formulation and development of criteria to evaluate the AOL design resulting from the use of these guidelines. This provides a means of verifying the applicability and usefulness of the derived guidelines in practical problems of AOL design.\n\n3. 6. 4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AOL Requirements Concepts</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>AOL Design Guidelines/Standards</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Design Evaluation Criteria</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated cost of development: $100K - $250K.\n3.6.5 Verification of Results\n\nThe guidelines derived for the study must be applied to specific AOL design projects to test the applicability of these guidelines to real-world NASA problems. The evaluation criteria will then be deployed as the tool for assessing the resulting design, which reflects on the usefulness of the derived guidelines in providing an effective AOL to an actual user.\n\n3.6.6 Related Studies\n\n- Software Technology Items.\n- TI-05 Standardization criteria for NASA software.\n- TI-07 AOL compiler generator cost factors.\n- TI-18 Guidelines for design documentation consistency.\n3.7 AOL Compiler Generator Cost Factors (TI-07)\n\n3.7.1 Problem Definition\n\nThe advent of increased development and usage of application-oriented languages (AOL) calls for design of an increasing number of compilers. Compilers being machine-dependent, the problem is further enlarged by the continuing spread in the number of different computers coming into usage. Compiler generation, however, has remained an expensive task. Thus in view of this expected increase in compiler design activities, it is necessary to look into why compilers cost so much. This study of investigating the factors contributing to the cost of compiler generation is viewed as one of relatively modest effort (2-3 man years). This will lead to methods of significantly reducing compiler generation cost.\n\n3.7.2 Technology Development Requirements\n\nThe requirements of this task are of a different nature from the other technology items. The end product is not a specific technique or software package, but a qualitative assessment of the major factors contributing to the cost of compiler design, from which it should be possible to derive techniques for reducing these costs.\n\nThat problems exist in compiler generation is a known fact. Why they exist is another question. The requirement of this task is to provide an answer in quantifiable terms that will lead to new and feasible approaches to the development of tools to support application growth.\n\n3.7.3 Suggested Approach\n\nThe study to be undertaken consists of three steps as shown in the schedule. The first step is to identify and typify representative AOL compiler generators used to generate payload application software. This will be followed by an in-depth analysis of the development history of these generators. The analysis must take into account the particular environmental constraints and other factors associated with the development of each of these generators. The analysis must identify the development cost and extract those factors contributing to the cost. Each of the contributing factors must be assessed in terms of significance and potential impact on future development programs. The result will be a comprehensive overall assessment of the problem of controlling costs in AOL compiler generation, and the identification of what steps must be taken to reduce future cost. This effort should be correlated with that under TI-06 to ensure that the final assessment reflects the benefits of development under TI-06.\n3.7.4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Action</td>\n<td>Identify typical AOL generators.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Trace development history.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Perform cost assessment.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated cost of development: $100K - $150K.\n\n3.7.5 Verification of Results\n\nThe end product will be a specific set of factors which will provide a tangible product in terms of the benefits accrued in future compiler generation programs. As such the test would be to apply the experience gained by the analysis of these cost factors in a test compiler generation exercise and to assess the associated costs relative to the costs of prior comparable programs.\n\n3.7.6 Related Studies\n\n- Software Technology Item.\n - TI-06 AOL design guidelines/standards.\n3.8 Interface Criteria for NASA-Distributed Processor Applications (TI-08)\n\n3.8.1 Problem Definition\n\nThe expanding role of distributed processor systems envisioned for future payloads and missions demands that the associated problems of interprocess communication and related aspects be studied in depth by NASA. This problem is being addressed for on-ground systems within the industry. However, the special implications of onboard near-real-time processing environments need to be carefully examined by NASA. The development of suitable interface criteria for NASA-distributed processor applications is one of modest cost (2-4 man years). However, it is mandatory in terms of integrating and absorbing the multiplicity of high rate data sources projected for the next decade.\n\n3.8.2 Technology Development Requirements\n\nInterface criteria to assist in the design of NASA-distributed processor interfaces represent the major end products expected of this technology development effort. The criteria are necessary to simplify problems of integration and to minimize associated costs by avoiding recourse to nonstandard interfaces. These developments are critical to increased and cost-effective utilization of distributed processor concepts and techniques, and are essential to the enablement of intelligent instruments.\n\n3.8.3 Suggested Approach\n\nThe first significant step of this effort is the identification of the potential distributed system configurations for deployment in near-real-time spaceborne environments. Once these are identified, it is necessary to analyze in detail each of these configurations to determine parametric characteristics such as data flow, and to establish appropriate control structures. These parameters characterize the interprocess communication needs. Based on these quantitatively established needs, the appropriate interprocess communication techniques can be selected through trade studies. This will in turn lead to the interface criteria which are essential to widespread deployment of distributed processor systems within the NASA programs.\n3.8.4 Schedule and Resources\n\n- Identify potential distributed configurations.\n- Characterize data and control flow.\n- Select interprocess communication techniques.\n- Establish interface criteria.\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated cost of developments: $100K - $200K.\n\n3.8.5 Verification of Results\n\nThe end product is a set of interface criteria. The test of its validity lies in its application to real-world problems, and verification can be achieved through test implementation of selected cases.\n\n3.8.6 Related Studies\n\n- Software Technology Items.\n - TI-01 Requirements decomposition and structuring guidelines.\n - TI-05 Standardization criteria for NASA software.\n - TI-09 Task control structures for distributed processor environments.\n - TI-10 Program organization methods for real-time fault recovery.\n - TI-15 Restructured image analysis software for parallel processing.\n\n-36-\n3.9 Task Control Structures for Distributed Processor Environments (TI-09)\n\n3.9.1 Problem Definition\n\nTask allocation and control is major significance in the design and operation of ground-based distributed systems and has received considerable attention. This function is much more critical in the management of real-time space-based distributed systems and it is decidedly in the NASA domain to tackle this problem. The task allocation process should ensure that the available resources are utilized to the fullest extent at all times and as efficiently as possible, given the particular tasks and processor configuration. Once the optimal task allocation is determined, then the actual task control should be implemented in accordance with the planned allocation. Development of the task control structure represents the other major part of the problem contained in this item. It is expected that, in view of the progress in ground-based systems, this effort will be of relatively low cost and require 2-5 man years of effort.\n\n3.9.2 Technology Development Requirements\n\nThe technology development requirements are twofold; (1) techniques for automatically determining the optimal task allocation and scheduling among the processors within the distributed system, and (2) design and development of control structures for enforcing the optimal task allocation and scheduling. These tasks are interrelated and should be carried out with close coordination between the two efforts. This item has particularly great applicability to the effort proposed under TI-15 (restructuring image analysis software for a parallel processing). The technology development efforts under this plan should therefore complement the other effort.\n\n3.9.3 Suggested Approach\n\nThe starting point for this plan is to clearly identify the scope and type of tasks as well as the nature of the distributed system environments expected to arise in the implementation of planned NASA missions. Concurrently, available techniques for on-ground distributed systems should be reviewed to delineate the deficiencies of such methods in meeting the requirements of real-time space systems. The two efforts together will provide the technical base for initiating the development of appropriate task allocation and scheduling techniques. These techniques should be amenable to automated implementation. This will lead to optimal allocation and scheduling of the tasks for any given processing problem.\nwithin the scope of the study. Next will be the development of suitable software control structures capable of implementing the optimal allocation and scheduling plans. The final step is testing of these techniques and control structures, through simulation of the onboard processing environments, to verify their reliability and efficiency.\n\n3.9.4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Task</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n- Requirements analysis.\n- Develop optimal task allocation and scheduling methods.\n- Develop task control structures.\n- Test and documentation.\n\nEstimated cost of development: $100K - $250K.\nResource requirements include computer facilities for simulation and testing.\n\n3.9.5 Verification of Results\n\nThe results in this case are the techniques for determining the optimal task allocation and scheduling and the control structures for their implementation. The verification process should therefore include simulation of the onboard real-time processing environment and testing of the developed techniques and control structures in such simulated environments. This will ensure that the resultant products of the study will meet the NASA requirements for distributed systems. It will also enable operational implementation of related technology developments (particularly the implementation of parallel processable image analysis functions: TI-15).\n\n3.9.6 Related Studies\n\n- **Software Technology Items.**\n - TI-01 Decomposition and structuring guidelines.\n - TI-05 Standardization criteria for NASA software.\n - TI-08 Interface criteria for NASA distributed processor applications.\n - TI-10 Program organization methods for real time fault recovery.\n- TI-15 Restructured image processing software for parallel processing.\n- TI-19 Software prototyping methods.\n3.10 Program Organization Methods for Real-Time Fault Recovery (TI-10)\n\n3.10.1 Problem Definition\n\nSoftware and hardware errors as well as data anomalies do occur in spite of the best of precautions in the design and development processes. It is therefore necessary that space systems should be backed by effective means of fault recovery. In view of the dynamic nature of the system environment, it is also crucial that this recovery be in near-real-time. Thus, the problem addressed in this study is the need for developing efficient techniques for real-time recovery from errors caused either by hardware, data, or software. The recovery procedures to be considered here are primarily limited to software rather than to purely hardware-oriented solutions such as redundant hardware. The proposed effort is of moderate to high cost (between 4-20 man years) depending on the depth to which the problem is to be explored.\n\n3.10.2 Technology Development Requirements\n\nThis effort includes review/development of recovery techniques most suited for NASA real-time space applications. This will be based on research into the structure and organization of software systems which provide reliable fault recovery through proper program organization methods. These developments should be coordinated with the activities proposed in other technology items, such as classification of error mechanisms (TI-17).\n\n3.10.3 Suggested Approach\n\nStructure analysis represents the first step of the proposed effort. This consists of identification of the types of faults likely to be encountered in real-time space systems and determination of the nature of the recovery process required to counteract these faults. Development of appropriate techniques and procedures for system recovery is the next step. This is followed by development of program organization methods which will maintain the status of the system so that the system can recover gracefully with minimum loss of data and control.\n\n3.10.4 Schedule and Resources\n\n- Real-time program structure analysis.\n- Recovery techniques.\n- Program organization methods.\n\nEstimated cost of development: $200K - $1000K.\n3.10.5 Verification of Results\n\nThe development methods should be tested and evaluated by simulation under appropriate fault-inducing environments. This is extremely essential to prove the reliability of the techniques for deployment in real-world applications wherein the risk factors associated with improper recovery cannot be tolerated.\n\n3.10.6 Related Studies\n\nSoftware Technology Items.\n\n- TI-01 Requirements decomposition and structuring guidelines.\n- TI-08 Interface criteria for NASA-distributed processor applications.\n- TI-09 Task control structures for distributed processor environments.\n- TI-12 Control structures for adaptive systems.\n- TI-15 Restructured image analysis software for parallel processing.\n- TI-17 Classification of error mechanisms.\n3.11 Adaptive High-Speed Buffering Techniques for Dynamic Networks (TI-11)\n\n3.11.1 Problem Definition\n\nMissions involving image acquisition and other high-rate data-generating instruments, call for advanced capability in all areas of the data acquisition, handling, and processing system. The variable data rates of different experiments and the need for intelligent data acquisition dictates that advanced techniques, capable of adapting to changing data environments, be developed. High-speed buffering techniques in dynamic acquisition and switching networks are of prime importance, particularly in view of the high-speed, large-scale memory capability expected in the near future. Methods for optimal utilization of potential buffer resources will have tremendous impact on information gathering systems. This study represents a moderate to high cost developmental effort requiring 5-15 man years.\n\n3.11.2 Technology Development Requirements\n\nThe technology development required by this item is the development of advanced high-speed buffering techniques capable of adapting to the dynamic characteristics of the data environment envisioned for future missions. These missions will involve high data rate experiments such as multispectral remote sensing of earth resources. This development is required to ensure that there will be an optimal utilization of the resources available both onboard and elsewhere in the total data system. This effort will contribute towards the overall objective of data system optimization by upgrading the state of the art in the key area of buffering techniques.\n\n3.11.3 Suggested Approach\n\nThis developmental effort consists of several distinct steps as indicated under the schedule. The first step is a detailed assessment of the existing technology to identify deficiencies in the state of the art in meeting the future requirements. This requirements analysis must be supported by a parallel effort to identify the possible advancements expected in related hardware/software technology areas. With these efforts as the technology base, the study will proceed with the main task of developing new adaptive techniques. The possibilities of incorporating at least some basic level of intelligence at the front end will be explored. For example, when one is only interested in change detection, only data that are subject to change need be stored. The developed techniques will then be implemented, tested, and documented to ensure a sound return for NASA investment.\n3.11.4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th>Year</th>\n<th>Task</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1978</td>\n<td>Survey available techniques.</td>\n</tr>\n<tr>\n<td>1979</td>\n<td>Identify advancements in related areas.</td>\n</tr>\n<tr>\n<td>1980</td>\n<td>Develop new adaptive techniques.</td>\n</tr>\n<tr>\n<td>1981</td>\n<td>Implement, test and document these techniques.</td>\n</tr>\n<tr>\n<td>1982</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated cost of development: $250K-750K.\n\n3.11.5 Verification of Results\n\nThe developed techniques will be implemented and tested under properly simulated data environments including the expected range of dynamic data characteristics. This requires a thorough knowledge of the state of the art in data system simulation techniques in addition to those needed in the development phase of the effort. This verification of results, in terms of capability for meeting real-time requirements and other needs of the data system, will serve to enhance the value of the effort and help its acceptance by the user community.\n\n3.11.6 Related Studies\n\n- Software Technology Items.\n - TI-19 Software prototyping methods.\n3. 12 Control Structures for Adaptive Systems (TI-12)\n\n3. 12. 1 Problem Definition\n\nAutomated intelligence activities involve a variety of scene analysis, image processing and pattern recognition functions. These functions have to be called upon for processing, depending on the environmental conditions, in different sequences and configurations. This dependency requires the system to be adaptive to the needs of the changing environment. The problem is therefore to provide adaptive framework for the dynamic selection of the many software functions required in autonomous missions. The development of appropriate control structure concepts is expected to be of moderate cost requiring 8-12 man years.\n\n3. 12. 2 Technology Development Requirements\n\nThe technology advancement required is the development of control structure concepts for adaptive control of software procedures. The desired software system requires certain cognitive and decision making capabilities to adaptively deploy the right processing modules in an autonomously operating environment. The core development required encompasses conceptual, algorithmic and implementational aspects of the problem.\n\n3. 12. 3 Suggested Approach\n\nThe initial step is to establish the requirements as stated above in more precise terms. A requirements analysis includes a review of the different processing functions involved in autonomous environments and their interrelationships. Once the specific processing functions and the possible configurations of their deployment are identified, it is then necessary to develop the concepts and techniques for adaptive control of these functions which can lead to optimal performance of the software system. This development of appropriate control structures will be followed up by experimental simulation (to check out the control structures under different test environments) and documentation to ensure its utility.\n\n3. 12. 4 Schedule and Resources\n\n- Identify the interdependencies and relationships of software functions.\n- Develop appropriate control structures.\n- Test and document the developed control structures.\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Task</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\nEstimated cost of development: $300K - $500K\nResource requirements include access to a computer system for test simulation of the developed control structures.\n\n3.12.5 Verification of Results\n\nA detailed simulation study plan must be formulated and implemented to ensure that the developed procedures meet their requirements. The simulation process should be carefully designed to provide an opportunity to test all feasible configuration options expected of the final software package.\n\n3.12.6 Related Studies\n\n- Software Technology Items.\n - TI-05 Standardization criteria for NASA software.\n - TI-14 Adaptive search and sort routines.\n - TI-15 Restructured image analysis software parallel processing.\n - TI-19 Software prototyping methods.\n3.13 Impacts of Natural Communication Methods on NASA Payload Systems (TI-13)\n\n3.13.1 Problem Definition\n\nMulti-experiment missions call for a more optimal utilization of human resources. The control and monitoring of the different experiments should be spread, to the extent feasible, over all the different human faculties capable of interaction and communication. The computer system in control of these experiments must provide for man-machine communications and should make the best use of all known natural communication methods. The problem is the need to extend the scope of methods used onboard for man-machine interaction. This effort is expected to be one of relatively modest cost involving 3-6 man years.\n\n3.13.2 Technology Development Requirements\n\nThe goal of natural communication methods is best furthered by a study geared to assess their impact on the design of payload software systems. The assessment process must necessarily include a detailed analysis of typical implementations of such methods to develop a thorough understanding of existing potential. The study must critically evaluate the technology associated with these methods to clearly identify the feasible or potentially applicable methods which meet the NASA requirements for onboard implementation.\n\n3.13.3 Suggested Approach\n\nThe starting point of this effort is a requirements analysis phase wherein the NASA requirements for natural communication methods in the upcoming missions are to be clearly identified and firmly established. Typical cases will be analyzed in depth through implementation/simulation to derive an understanding of their influence and potential impact on the supporting payload software system. This will lead not only to an evaluation of the feasibility of using these natural communication methods onboard, but also to an assessment of the necessary and desirable modifications to payload software system design. The results of such test case studies are then reviewed to derive an overall assessment of natural communication methods on space systems.\n3.13.4 Schedule and Resources\n\n- Identify NASA requirements for natural communication methods.\n- Study the impact of these methods through analysis of typical implementations.\n- Delineate necessary modifications to payload software system.\n- Obtain an overall assessment of natural communication methods.\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated development costs: $150K - $250K.\nResources include the hardware for test implementation in a simulated onboard processing environment.\n\n3.13.5 Verification of Results\n\nThe feasibility of employing the different natural communications methods will be verified by actual implementation in a simulated onboard processing environment. Such implementation will additionally lead to testing the supporting software system, thus enabling useful and reliable insight into all the different facets associated with natural communication techniques.\n\n3.13.6 Related Studies\n\n- Software Technology Items.\n\n - TI-08 Interface criteria for NASA-distributed processor applications.\n3.14 Adaptive Search and Sort Routines (TI-14)\n\n3.14.1 Problem Definition\n\nMany of the pattern classification and image analysis techniques basic to an image processing system involve table look-up procedures operating on large arrays. These procedures necessarily call for search and sort operations in both the table formulation and look-up phases. The process is repeated innumerable times, especially in the look-up phase. This is because of the extensive volume of data handled by missions such as those involving earth resources survey and similar large imagery data acquisition experiments. It is therefore necessary to make such repeated table look-up operations as efficient as possible if images are to be processed onboard. Therefore, more efficient search/sort procedures are needed.\n\nThe problem facing the study is the need to overcome the possible inadequacies of presently known methodology in meeting the future onboard real-time processing system requirements. Further, it is desirable for these procedures to be adaptive to the array data characteristics to ensure optimum performance. It is expected that the required study is of relatively modest cost and will be approximately 3-6 man years of effort. This is because of the significant amount of related work reported in the area of search and sort techniques as applied to ground environments.\n\n3.14.2 Technology Development Requirements\n\nThe technology development requirements can be precisely stated as the development of a set of search and sort routines and associated software control structures for adaptively selecting the appropriate routines for different data environments. This requires identification of the most appropriate methods for different array data characteristics. This will be done through review and modification of existing methods and/or additional developments followed by integration of these procedures within an adaptive structure.\n\n3.14.3 Suggested Approach\n\nThe first step of this development study is a detailed requirements analysis. This consists of a close scrutiny of the major pattern classification and image processing techniques to identify the specific needs for efficient search/sort procedures. These needs must be analyzed in the context of available information about the data rates, image sizes and such other related items pertaining to the data environment expected in future missions. This leads to a detailed definition of the requirements for\nsearch/sort routines under different identifiable classes of data environment characteristics as well as associated time constraints for possible real-time implementation.\n\nThe next step is to evaluate the available search/sort procedures in terms of their ability to meet these requirements and identify the potential candidates for adaptation. These candidate techniques are modified, improved and combined to enhance their potential. This effort may include the development of completely new methodology. However, such a need may not arise in view of the extensive work being performed on ground-based systems. The selected set of modified/developed techniques deemed optimal for the different data environments are then integrated into appropriate software control structures. These software control structures will be able to recognize the data environment characteristics and route the data flow through the appropriate software modules. The developed package will then be tested in simulated data environments to verify and validate the end product of the study.\n\n3.14.4 Schedule and Resources\n\n- Requirements analysis.\n- Develop adaptive routines and integrate them through appropriate control structures.\n- Implement, test and document the adaptive routines package.\n\nEstimated development costs: $150K - $250K.\nResource requirements include access to a computer system capable of simulating the different data environments expected onboard.\n\n3.14.5 Verification of Results\n\nThe developed set of procedures and their adaptive capabilities must be verified by simulation of the different data environments. This calls for appropriate simulation tools including a computer system of sufficient computational power. The verification process should be performed both at the level of individual routines to assess individual performances and at the integrated level to verify the adaptation capabilities of the total system.\n3.14.6 Related Studies\n\n- Software Technology Items.\n - TI-05 Standardization criteria for NASA software.\n - TI-12 Control structures for adaptive systems.\n - TI-15 Restructured image analysis software for parallel processing.\n - TI-16 Optimal large array partitioning procedures.\n - TI-19 Software prototyping methods.\n3.15 **Restricted Image Analysis Software for Parallel Processing (TI-15)**\n\n3.15.1 Problem Definition\n\nParallel processing is an attractive concept for the efficient realization of image processing and pattern recognition functions onboard NASA payloads in the coming decades. However, existing software techniques in the image analysis area are structured only for batch processing in conventional sequential processing environments on ground. Therefore, image analysis software must be appropriately tailored for implementation in parallel processing environments. The effort required for meeting the needs of this concept is expected to be moderately large in scope and to span 10-25 man years, depending on the number of software functions to be covered by the effort.\n\n3.15.2 Technology Development Requirements\n\nThe enabling of onboard near-real-time image processing and pattern recognition activities requires full utilization of parallel processing technology to minimize the processing time required. This calls for operationally efficient software, structured to take advantage of the parallel processing environments feasible onboard in the next decade. Hence, the major technology needed is the restructuring of image analysis software which is considered crucial to the enablement of image processing and pattern recognition activities onboard.\n\n3.15.3 Suggested Approach\n\nParallelism can be visualized in terms of performing identical processing on different segments of an image or data array using parallel processing elements. It can also be visualized in the sense of carrying out independent computations on the same segment of data concurrently through different processing elements. It is therefore necessary to explore all such feasible parallelism in the major image processing functions of consequence to onboard implementation. For this purpose, it is also necessary to assess the state of the art in parallel processing techniques and supportive low cost hardware technology. This will help in determining the level or extent of parallelism advisable from a practical viewpoint.\n\nHaving identified the feasible and practical parallel processable functions and the key techniques, the software is accordingly restructured to achieve the maximum parallel processability. This is followed by identifying the appropriate computer architecture and control structure for implementing the restructured software system. In this context, the\nimpact of developments in the area of optical and hybrid (optical and digital) processing should be assessed to ensure that the restructured system does not attempt to perform functions that are more efficient in optical processing techniques. This assessment must include the complexities of transforming images between digital to optical domains as that tends to offset the advantages of optical processing.\n\n3.15.4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n- Identify parallel processable functions.\n- Restructure/modify the software to achieve maximum parallel processability.\n- Identify the appropriate computer architecture for implementing the restructured software system.\n\nEstimated development costs: $500K-$1000K\n\nResources include hardware for testing the restructured software in appropriate parallel processing environment.\n\n3.15.5 Verification of Results\n\nThe results are to be verified through tests involving classes of multispectral data. Experiments should be performed with both the original and restructured software (the latter in parallel processing environment) to verify the correctness of the restructured software and to determine the computational gains achieved through parallel processing. This aids in verifying and validating the computer architecture and control structures to be used for purposes of onboard image processing.\n\n3.15.6 Related Studies\n\n- Software Technology Items,\n - TI-01 Requirements decomposition and structuring guidelines.\n- TI-05 Standardization criteria for NASA software.\n- TI-08 Interfacing criteria for NASA distributed processor applications.\n- TI-09 Task control structures for distributed processor environments.\n- TI-12 Control structures for adaptive systems.\n- TI-20 Software prototyping methods.\n3.16 Optimal Large Array Partitioning Procedures (TI-16)\n\n3.16.1 Problem Definition\n\nManipulations of large two- and three-dimensional arrays which arise in the implementation of many data compression and image processing functions pose an operational problem that is far from trivial. Quite often the transposition of a matrix which is too large to fit in core, may require more time than performing basic transform or other operations on the rows and columns of this matrix. In addition, the complexity of a large number of input/output operations demands more efficiency in manipulating large arrays under the constraints of a real-time image analysis system.\n\nThis problem was identified in Technology Driver PS-15, Efficient Large Array Manipulation Procedures. A solution is expected to result from a study effort of relatively modest cost (3-6 man years).\n\n3.16.2 Technology Development Requirements\n\nThe technology developments required to solve the problem defined above can be summarized as the development of optimal large array partitioning procedures. The resulting procedures should be capable of adapting themselves to the array data characteristics, i.e., the actual procedure used must be tailored to the array data characteristics expected in the corresponding environment. Currently known and reported methodologies for performing such matrix transpositions must be evaluated to pinpoint deficiencies in meeting the requirements of onboard real-time image processors. Partitioning of the arrays is a feasible approach in meeting the constraints expected. It is necessary to develop partitioning procedures which make the best use of the available computational resources and at the same time minimize time utilization. This technology development program shall study the impact of advancements in hardware technology such as electronic cyclic memories. This will ensure that the developed procedures are consonant with the state of the art in related fields, and that the resulting methodologies will meet the NASA requirements in the most efficient manner.\n\n3.16.3 Suggested Approach\n\nFirst, the study should consider the onboard processing system architecture (and constraints) expected by mid 1980's, and should restructure the optimal control problem accordingly. Second, alternatives to the dynamic programming approach should be explored.\nThird, the feasibility of adapting the procedures to array data characteristics should be investigated. Fourth, the impact of technological advancements such as electronic cyclic memories on the manipulation procedures should be studied. The study should then be directed towards the development of suitable optimal partitioning procedures which can be applied to a variety of onboard processing environments. The deliverable end product items will be a set of strategies or optimal large array partitioning procedures which will lead to best utilization of the available onboard computational resources. In addition these procedures shall be adaptive to the array data characteristics.\n\n3.16.4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Study feasibility for adapting array manipulation procedures to array data characteristics.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Determine interrelationships of these procedures with data storage and processor architecture.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Develop, test and document these procedures.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated development costs: $150K-250K. Resource requirements include access to a computer system capable of simulating different onboard processor environments.\n\n3.16.5 Verification of Results\n\nThe methodology developed must be tested in different simulated onboard environments on a ground-based computer system to validate and verify optimality. The tests should be designed to cover a wide variety of array data characteristics to prove the adaptability of the resulting procedures to such characteristics. These tests will ensure the success of the task undertaken and can lead to advancement of the technology to the next level required for actual onboard implementation.\n3.16.6 Related Studies\n\n- Software Technology Items.\n - TI-05 Standardization criteria for NASA software.\n - TI-12 Control structure for adaptive system.\n - TI-14 Adaptive search and sort routines.\n3.17 Classification of Error Mechanisms (TI-17)\n\n3.17.1 Problem Definition\n\n\"Learning from History\" is the most often suggested route for avoiding repetition of previously encountered errors. This is particularly valid in the case of software errors because of the lack of standardization in software design procedures and the consequent tendency to fall into the same errors repeatedly. The problem is therefore the need for development of avoidance techniques through a process of identification and classification of error mechanisms recorded in past software projects. NASA experience in space systems is particularly applicable. The effort required here is approximately 3-6 man years. The return, although perhaps difficult to measure, can be substantial in terms of cost avoidance.\n\n3.17.2 Technology Development Requirements\n\nThe technology developments required here are quite unlike others in that the end product is not so much a methodology but a directory categorizing the different types of software errors and the factors which lead to them. This categorization or classification of error mechanisms will be derived through analysis of prevalent errors encountered in prior space software development programs. Guidelines will thereby be developed to ensure that those pursuing future software development will be forewarned of potential faults.\n\n3.17.3 Suggested Approach\n\nThe first step of the study is the compilation of errors documented under the different NASA software development projects of the past space programs. (This requires free access to such information by the organization conducting the study.) The compiled list should then be critically reviewed and grouped on the basis of common characteristics. An understanding of the causes of such errors will aid in developing classification of the error mechanisms. Guidelines will be developed to avoid these types of software errors in future design projects. This approach can be expected to enhance the search for fault-free software development in future NASA programs.\n3.17.4 Schedule and Resources\n\n- Compile error data of past NASA software program projects.\n- Review and study the errors to extract their characteristics and model these errors into identifiable classes.\n- Derive an overall comprehensive list of these error classes.\n- Develop guidelines for avoiding such errors in future projects.\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated cost of development $150K - $250K. Resources include unrestricted access to documented reports of experience of prior NASA software development programs.\n\n3.17.5 Verification of Results\n\nThe concept of verification of results is not valid in the usual sense of the phrase as only future experience can prove the value of the guidelines developed from this process of classification of error mechanisms. However, a small scale software development program can be carried through in the light of these results and error avoidance costs estimated in a subjective manner. As in many research items, insight into the underlying causes of an effect can lead to unrelated advancements in technology.\n\n3.17.6 Related Studies\n\nThis Technology Item relates to all software development technology areas.\n3.18 Guidelines for Design Documentation Consistency (TI-18)\n\n3.18.1 Problem Definition\n\nAn important aspect of software design process, which has received much attention, but few solutions, is the method of documentation of software design. No satisfactory method has been developed of conveying requirements into design representations which are understandable throughout the evolving responsibilities of a program life cycle. Attempts have been made to use data flow diagrams, functional representations, networks and other means. Though each may have specific advantages, none satisfies the need for unique clarity and understandability in a universal sense.\n\nInadequate details, lack of consistency and such other drawbacks in the documentation of the design can cause misinterpretation of the intent of the software designer by the programmer in the coding phase. This results in error-prone software with low reliability and consequent high costs in its maintenance. It is therefore clear that the lack of proper guidelines for design documentation represents a problem of sufficient importance to be addressed by NASA to ensure the developed software is space-worthy. The effort required to meet this problem effectively is expected to be one of relatively modest cost involving 2-5 man years.\n\n3.18.2 Technology Development Requirements\n\nThe developments expected of this study are the guidelines for consistency in design documentation which can facilitate clear understanding of the design coding requirements. This will enhance the scope for higher reliability in the generated code, thereby reducing maintenance. This is a desirable objective in space-related environments of concern to NASA. The guidelines should be broad enough in scope to cover the spectrum of NASA payload software activities and specific enough to be directly applied to the software development projects in the coming decade.\n\n3.18.3 Suggested Approach\n\nThe effort should be closely coordinated with other software design-related Technology Items such as requirements decomposition and structuring guidelines, and AOL design guidelines/standards. The first step of this effort is to develop a clear understanding of the state-of-the-art design techniques (and hence the need to coordinate with efforts leading to improved design techniques). This will ensure that the design structure and all associated aspects are known and their implications are completely grasped prior to the development of documentation guidelines. This design structure analysis will be followed by formulation of the actual guidelines for achieving\nconsistency in design documentation. The next step is the development of evaluation criteria to measure the effectiveness of these guidelines.\n\n3.18.4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Design structure analysis.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Development of documentation guidelines.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Evaluation criteria.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated cost of development: $100K - $250K.\n\n3.18.5 Verification of Results\n\nThe guidelines can be effectively verified as to their worth by application to real-world software design documentation efforts. The resulting documentation is assessed on the basis of the evaluation criteria developed as part of the study. This leads to a measure of effectiveness in achieving design documentation consistency.\n\n3.18.6 Related Studies\n\n- Software Technology Items.\n - TI-01 Requirements decomposition and structuring guidelines.\n - TI-05 Standardization criteria for NASA software.\n - TI-06 AOL design guidelines/standards.\n3.19 Software Prototyping Methods (TI-19)\n\n3.19.1 Problem Definition\n\nSoftware design errors and the associated costs are always a matter of grave concern to software development projects. Even more disconcerting is the discovery that a design will not meet requirements after implementation is complete. It is therefore highly desirable to develop methods for proving the software design before committing the design to code. This is the objective of software prototyping methods. Software prototyping will provide low-cost pretesting of the key elements of the design prior to implementation of the operational system. This technology when properly developed and used offers great benefits in reliability and cost avoidance. The development effort is expected to be one of relatively modest cost involving 2-5 man years.\n\n3.19.2 Technology Development Requirements\n\nThe technology to be developed under this study is the means of testing software design prior to implementation of the system. Such development will cut the high cost associated with design errors both in terms of their potential effects on reliability and in terms of the actual expenses involved in correcting these errors or making false starts. The methods to be used to achieve software prototyping capabilities represents the major requirement of this development study. Also, suitable evaluation criteria must be developed to assess the effectiveness of these methods.\n\n3.19.3 Suggested Approach\n\nThe effort must be mainly directed towards the development of methods suitable for prototyping real-time space systems. It is necessary to assess the technology currently available in the area of ground-based prototyping techniques prior to exploring the scope for prototyping onboard real-time systems. The current technology analysis will then provide pointers for extrapolation of these techniques into the domain of space. This extension may not be straightforward in that the environmental constraints associated with space systems are likely to be of an entirely different category. The final stage of the effort is the development of appropriate evaluation criteria for assessing the developed techniques.\n3.19.4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Technology analysis.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Low-cost prototyping methods.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Evaluation criteria.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated cost of development: $100K-250K.\n\n3.19.5 Verification of Results\n\nThe end product of this effort and its effectiveness can be judged by application to specific cases of software design and development programs. The evaluation criteria developed as part of this technology development study will be used to assess the gains and verify the efficiency of the tools resulting from the study. Comparative analysis with non-prototype development will be performed where systems with similar requirements can be identified.\n\n3.19.6 Related Studies\n\nThis Technology Item is applicable to all software development technology.\n3.20 **Software Technology Monitoring (TI-20)**\n\n3.20.1 Problem Definition\n\nNASA should capitalize on the continuous evolution and the occasional breakthroughs occurring in the areas of hardware/software technology. A process of early awareness of the developments is needed followed by a study of the impacts of such developments on NASA programs. This requires that there be a constant monitoring of the developments in the field and for this purpose it is necessary that NASA establish a suitable formal mechanism.\n\nAs an Item, software technology monitoring seems obvious and deceptively simple. NASA personnel are continually monitoring technology and providing much of the advancement. However, this monitoring basically applies to a specific area of interest of the person or group doing the monitoring. The key to this task is to have a central source monitoring all software/hardware technology and correlating advancements to ongoing or proposed space activities wherever they may be applicable. This is to be an on-going low level effort of relatively low cost, requiring 1 man year per year.\n\n3.20.2 Technology Development Requirements\n\nIn this case, the requirement is not truly one of technology development but rather one of technology assessment. However, the requirements can be viewed as developing and instituting a formal software technology monitoring mechanism. Such a mechanism would be responsible for performing the monitoring activity and correlating developments with the NASA requirements. It would thereby contribute towards identification of additions (and/or deletions) to the NASA Software Technology Item roster.\n\n3.20.3 Suggested Approach\n\nThe formal mechanism set up for this purpose should have access to information about activities from different sources within NASA and outside of it also, to the extent feasible. This is in addition to the open literature publications which are easily accessible. The formal mechanism should utilize the modern techniques of technology forecasting and assessment, such as advanced DELPHI techniques, not only for monitoring but also to identify the expected course of developments. This activity being an on-going effort, the projections can be verified whenever promising technology is identified.\n3. 20. 4 Schedule and Resources\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Action</td>\n<td>Monitor software technology advances.</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nEstimated development costs: $50K/year.\n\n3. 20. 5 Verification of Results\n\nThis Technology Item is significantly different from others; therefore the concept of verification results does not apply in its usual sense. However, the projections on future developments made earlier can be verified by the monitoring process, thereby refining the assessment methodology.\n\n3. 20. 6 Related Studies\n\nNot applicable (except in the sense that the Technology Item is related to the total area of software technology).\nThis appendix serves to provide a summary description of each of the fifteen technology drivers (listed below) derived from an analysis of the technology emphasis areas during Phase 1 of this study and described in the Mid-Term Report (No. 76-0084), NAS8-32047, December 24, 1976, by M&S Computing, Inc.\n\n<table>\n<thead>\n<tr>\n<th>Sl. No.</th>\n<th>Technology Driver Title</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>PS-01</td>\n<td>Software Design Engineering</td>\n</tr>\n<tr>\n<td>PS-02</td>\n<td>Trend Toward Software Development by Non-Programmers</td>\n</tr>\n<tr>\n<td>PS-03</td>\n<td>Fault-Free Software</td>\n</tr>\n<tr>\n<td>PS-04</td>\n<td>AOL Design Methodology</td>\n</tr>\n<tr>\n<td>PS-05</td>\n<td>Low Cost Development of AOL Compilers</td>\n</tr>\n<tr>\n<td>PS-06</td>\n<td>(Distributed) System Partitioning/Interconnection Techniques</td>\n</tr>\n<tr>\n<td>PS-07</td>\n<td>Very Large Storage Access Simplification</td>\n</tr>\n<tr>\n<td>PS-08</td>\n<td>Software Fault Detection</td>\n</tr>\n<tr>\n<td>PS-09</td>\n<td>Software Recovery (after fault detection)</td>\n</tr>\n<tr>\n<td>PS-10</td>\n<td>High Speed Buffering Techniques</td>\n</tr>\n<tr>\n<td>PS-11</td>\n<td>Design and Control of Adaptive Software Procedures</td>\n</tr>\n<tr>\n<td>PS-12</td>\n<td>Natural Communication Methods</td>\n</tr>\n<tr>\n<td>PS-13</td>\n<td>Efficient Large Array Search and Sort Procedures</td>\n</tr>\n<tr>\n<td>PS-14</td>\n<td>Parallel Processing Techniques</td>\n</tr>\n<tr>\n<td>PS-15</td>\n<td>Efficient Large Array Manipulation Procedures</td>\n</tr>\n</tbody>\n</table>\nSOFTWARE DESIGN ENGINEERING (PS-01)\n\nA review of software development technology shows that hardly any of the facets of software development are being satisfactorily performed at the present time. Furtherance of the state of the art in all these facets (except perhaps in the actual coding phase) is not only desirable but also essential to ensure meeting the NASA payload software requirements. While each facet in itself can be viewed as a Technology Driver, it is possible to identify a basic common denominator contributing to the deficiencies in these areas. This key feature is the software design engineering. Software design engineering embraces all the different stages from an understanding and interpretation of the user-specified requirements through the documentation of the design. Some of the aspects to be considered are visibility of design, traceability, requirements documentation, design techniques, structuring, consistency, and design documentation. The entire spectrum of requirements analysis and design process is thus covered by this Technology Driver. Software costs and reliability goals will be met only when software design engineering becomes a reality. This is particularly important in the context of NASA payload software wherein the software requirements are more difficult to define and reliability considerations are of utmost significance.\n\nTREND TOWARDS SOFTWARE DEVELOPMENT BY NON-PROGRAMMERS (PS-02)\n\nThe availability and consequent increased use of low-cost microprocessor technology has resulted in highly distributed processing systems which most often rely on software support from non-programmer professionals. This trend has resulted in high cost, redundant software development, a lack of consistency, and a multiplicity of problems during operation and maintenance. Therefore, development of appropriate new software development concepts and methodology is required. Tools (in the form of higher level languages and simpler operating systems) which can simplify the software development process are called for to meet the demands which potentially arise from the advent of low-cost microprocessor technology. The need to provide aids for efficient, low-cost software development by non-professional programmers thus represents a Technology Driver of considerable significance.\n\nFAULT-FREE SOFTWARE (PS-03)\n\nCentral to the performance of space missions (especially long life autonomous type of missions) is the need for highly reliable software. By definition, fault-free software is software with no internal errors. Of course,\nfault-free software alone does not ensure reliable performance but represents only a positive condition for such reliability. External errors in data and hardware can still contribute to the information processing system failures. However, analysis of this facet of the problem, in terms of developing guidelines and methodologies to ensure fault-free software development, reduces the risk of catastrophic failures (such as those which caused, in the early 1970's, a French meteorological satellite to erroneously send destructive signals to 72 out of 141 high altitude weather balloons). Analysis also provides a solid base on which fault-tolerant systems can be built. Hence, fault-free software is deemed a Technology Driver in meeting NASA payload software requirements.\n\nAOL DESIGN METHODOLOGY (PS-04)\n\nThe growing use of application-oriented languages (AOL) by a continually expanding user community places a burden on the space-based information processing systems and its management by NASA. This burden, in the form of reduced reliability and higher costs (because of an additional compiler for each new language), is caused principally by a lack of commonality in approach to AOL development. This results in very little consistency and dictates that guidelines and standards for the design of AOL's as well as evaluation criteria for their assessment should be developed. Therefore, NASA should consider this aspect of software engineering as a prime area of concern and accordingly view it as a Technology Driver under this study.\n\nLOW COST DEVELOPMENT OF AOL COMPILERS (PS-05)\n\nThis Technology Driver represents an area of concern that is closely connected with PS04 and, in fact, represents a \"down the stream\" concern from the previous one. Development of AOL compilers and their costs are closely tied to the AOL design aspects in that a better and more consistent AOL design requires simpler and less expensive compiler generation efforts. However, the problem of compiler costs is further complicated by the continual proliferation in the types of computer systems coming into usage. A new compiler is needed not only for each new language but also for each new computer environment in which it is to be deployed. It is therefore necessary to look to this aspect as separate from the problem of AOL design. As such, this is identified here as an independent Technology Driver.\n\nDISTRIBUTED SYSTEM PARTITIONING/INTERCONNECTION TECHNIQUES (PS-06)\n\nDistributed systems, in the context of this description, are defined as systems of multiple processors each having its own executive and memory but performing specific dedicated processing functions as a part of an overall\nsingle partitioned system. While this concept is not new in itself, the progress in hardware technology, particularly the advent of microprocessors, has brought it to the forefront. The advantages of such distributed processing brings in its wake problems of complexity in system design and integration of subsystems. Associated with this facet of information processing are the problems of interprocess communication and optimal distribution of the processing functions among the components. These and other related aspects are covered by this Technology Driver and accordingly viewed as an area needing further attention from NASA in order to meet onboard, real-time, distributed processing needs.\n\nVERY LARGE STORAGE ACCESS SIMPLIFICATION (PS-07)\n\nAvailability of very large, low-cost storage, which presently lags behind other hardware technology in its status, can be expected to gain more attention in the coming decade. Accessing very large memories will entail far more complexity than is now necessary. In addition, the number of non-programmers, with the need for such capabilities, will continue to increase, and their needs must be met by appropriate developments in the software area. This need to simplify access to large storage on a routine basis is expected to become critical from NASA's point of view with the increased demand on high-volume, data rate-oriented space systems. Accordingly, it is viewed as a Technology Driver of importance.\n\nSOFTWARE FAULT DETECTION (PS-08)\n\nSoftware, however much it is checked for faults, cannot be formally proven to be fault-free, especially in the case of large software packages. Further, even the internally fault-free software may fail in operation due to external errors in data and hardware. It is therefore essential that suitable means for fault detection should be inculcated into the system. Such fault detection during execution can alleviate the problem of system failures through initiation of appropriate action to confine the error (from further propagation within the system) and enable recovery. Such recovery and error confinement are very critical to NASA payloads, and as such software fault detection is viewed as a Technology Driver of consequence.\n\nSOFTWARE RECOVERY (AFTER FAULT DETECTION) (PS-09)\n\nThis represents the third facet of the software reliability goals to be pursued by NASA to meet its long term requirements. The first facet involves studies aimed at fault-free software, the second is fault detection during execution, and the third is recovery from such faults after detection.\nAccordingly, this Technology Driver rounds out those identified earlier as PS-03 and PS-08 and combined the three contribute towards fulfilling the NASA software reliability requirements. Thus because recovery in real time from detected faults is essential to the success of missions, it is viewed as a primary area of concern - a Technology Driver.\n\nHIGH SPEED BUFFERING TECHNIQUES (PS-10)\n\nThe earth-oriented nature of future missions will result in onboard data acquisition at very high rates. These projected rates are far beyond the capabilities of present data acquisition, buffering, and processing systems. Consequently, extremely large buffers and associated high speed buffering techniques have to be contemplated in viewing the data systems of the 1980's. High speed buffering techniques are viewed as a Technology Driver of significance to this study.\n\nDESIGN AND CONTROL OF ADAPTIVE SOFTWARE PROCEDURES (PS-11)\n\nMany of the information processing procedures associated with automated intelligence environments such as scene analysis, pattern recognition, and image processing involve a considerably large number of specific processing functions. While each of these may be simple in itself, the many possible configurations of employing them make the task of control of these software procedures complex and challenging. This is the case even if a person is involved in the loop for deciding on the particular configuration most suited to a given data environment. In autonomous environments requiring automated intelligence capabilities, this adaptive selection and execution of specific processing logic modules becomes a critical capability and should be incorporated into the software system. The design and control of such adaptive software procedures is viewed as a Technology Driver of importance to NASA missions requiring autonomous operation capabilities.\n\nNATURAL COMMUNICATION METHODS (PS-12)\n\nBecause human resources are at a premium on space vehicles, it is desirable to explore all avenues for minimizing the demand on these resources or, alternatively, expanding the potential of the available resources to the fullest extent. In the case of man-machine interaction, this can be achieved by making the machine capable of interacting with the man in the manner that is most suited to the man, i.e., through natural communication methods. Exploitation of the full potential of the natural communication methods for onboard implementation would result in optimal utilization of human resources. It is therefore desirable for NASA to look into this area, and natural communication methods are thus being identified here as a Technology Driver.\nEFFICIENT LARGE ARRAY SEARCH AND SORT PROCEDURES (PS-13)\n\nMost pattern classification software techniques can be efficiently structured by use of table look-up procedures. Such table look-up procedures generally involve large size tables, and consequently both the table formulation and look-up phases involve considerable search/sort operations. Further, these operations are highly data-dependent in terms of the resulting computational loads. The very high data rates associated with the imagery applications and the consequent need for repeated high speed data-dependent table look-up operations dictates that the search/sort operations should be as efficient as possible under the related environment. It is therefore necessary and desirable, from the point of view of enabling onboard image analysis and classification, to evolve efficient large array search/sort procedures.\n\nPARALLEL PROCESSING TECHNIQUES (PS-14)\n\nParallel processing techniques have come to the forefront with the advent of distributed systems made practical by availability of low-cost microprocessors and related hardware technology. While the general area is under active study, the aspect of exploring its application to image analysis and exploiting its potential in this context has not been given sufficient attention. The concept of parallel processing is especially attractive given the nature of processing involved in the analysis of large images (identical independent processing of a large number of data points in a two-dimensional data array). An in-depth exploitation of the concept in the context of image processing functions is accordingly viewed as a Technology Driver as it leads to more efficient use of the computational resources available onboard and enables onboard implementation of some of these functions (which otherwise would be considered not feasible).\n\nEFFICIENT LARGE ARRAY MANIPULATION PROCEDURES (PS-15)\n\nData compression, image enhancement, and such other image analysis operations involve two-dimensional processing requiring manipulations such as matrix transposition (of the two-dimensional image data matrix). This problem is important in actual environments involving large images, for it precludes the possibility of holding the total image in core all at once. The desirability of addressing this problem becomes even more apparent when one considers the fact that this manipulation can take significantly more computational effort (and time) than the rest of the processing being carried out on the image. Accordingly, this need for efficient large array manipulation procedures is viewed as a Technology Driver in meeting the NASA requirements of image analysis capabilities.\n<table>\n<thead>\n<tr>\n<th></th>\n<th>SOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1.</td>\n<td><strong>Technology Driver:</strong> Software Design Engineering</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>No. PS-01</strong></td>\n</tr>\n<tr>\n<td>2.</td>\n<td><strong>Technology Category:</strong> Software Development</td>\n</tr>\n<tr>\n<td>3.</td>\n<td><strong>Missions Affected:</strong> All</td>\n</tr>\n<tr>\n<td>4.</td>\n<td><strong>Impact Date:</strong> 1978</td>\n</tr>\n</tbody>\n</table>\n| 5. | **Driver Description:** \n Currently, no facet of software development can be considered as being satisfactorily performed in a production mode, i.e., major shortcomings are identifiable in every step of the development process (with the possible exception of coding). There is a general feeling of inadequacy, dissatisfaction, and a lack of confidence in the merits of proposed solutions. Almost every facet of software development can, therefore, be a Technology Driver. Further investigation into the problems, proposed solutions, and status of technology development reveal, however, a common cause of difficulties. The key to this common cause is the lack of Software Design Engineering technology. Software Design Engineering is conceived to cover interpretation of requirements and creation of a design, but not the physical implementation of the software. \n\n6. | **Applicability to Payloads:** \n This software design problem is an even more difficult problem in the area of payload software than it is in most other areas. Payload software is generally part of an \"embedded\" system, that is, a computer system that is only part of, and integrated into, an equipment complex such as an avionics system. The software design problem itself is difficult enough, but in the \"embedded\" system, these difficulties are multiplied by the external constraints imposed by the total system. \n\n7. | **Current Technology Efforts:** \n Current and past technology developments have primarily addressed the development cycle from the point that a complete design specification is available. Some effort has been made in formalizing the design specification; however, only recently has recognition been given to the fact that all successes and failures\n7. Very little effort has been invested in \"embedded\" systems. Activity within industry is now centered on development of machine-analyzable, computer-aided requirements analysis software systems (e.g., ISDOS, SREP). These involve problem statement languages and language analyzers. Simulation techniques are slowly being improved. Top Down design is receiving more emphasis. Studies of how to use it and how to represent control structures and data interaction are growing. Modularization and structural design techniques are beginning, although, decomposition rules for system structures are poorly understood and decomposition consistency has not materialized. Better design representations are beginning to appear (e.g., HIPO, PROVAC). Some attempts are being made to develop machine processable design representations (PDL). MSFC is currently developing a Software Specification and Evaluation System (SSES) which shows promise.\n\n8. Current Major Problems: There is a general lack of knowledge of Software Design Engineering as a whole. The design process is not well understood. There is little guidance for designers and little knowledge of what a designer does or how he does it. Software requirements are mostly represented in free-form English specifications which use ambiguous terms and words with unspecified definitions. There is a lack of consistency from requirements to final design specification. Most design is still manual and Bottom-Up. Interface and integration questions are usually not considered until late in the design process if not ignored completely. Top down techniques are slow in developing because so little is known about how to decompose a system structure into proper functions. This is particularly critical with the advent of distributed system techniques in space applications and will continue to be until there are firmly established principles as to how a system should be distributed. Until these problems are resolved, software will continue to be costly and unreliable.\n\n9. Technology Advancements Required: Technology advancements must be made to provide visibility of design, improve design techniques, and establish realistic design evaluation methods. Specifically, technology advances must be made in the following areas:\n\n- Computer-aided design for control structures and data structures.\n9. (Cont'd)\n\n- Methods of designing and describing interfaces.\n- Development of a better understanding of error mechanisms.\n- Development of rules for the decomposition of system structures.\n- Development of techniques to enable consistency of decomposition of requirement and specifications descriptions.\n- Development of methods of deriving module definitions.\n- Improvement to modeling and simulation techniques.\n- Development of software prototyping techniques.\n- Derivation of design techniques for development of manageable, testable, and maintainable programs.\n\nThese areas are of general interest across the industry and are being vigorously pursued; as for example, the development of computer aided requirements and specification language development projects such as the ISDOS project sponsored by the aerospace and government organizations, CARA sponsored by the U. S. Air Force, and SREP sponsored by BMDATC. However, there are some technology items whose developments will have direct bearing on future NASA space activities and to some extent are unique to NASA (in terms of the need to develop real-time distributed systems and distributed data networks for space applications). These are:\n\n- Development of requirements decomposition and structuring guidelines.\n- Development of methods of designing and describing interfaces.\n- Development of guidelines for design documentation consistency.\n- Software prototype methods.\nAdvances in these areas would provide the knowledge required to partition systems, distribute functions and subsequently determine whether these functions are more appropriate to software or hardware implementations.\n\nThe approach basically consists of taking the theoretical work done by L. L. Constantine and others and applying it to the real problem presented by the processing requirements of future space systems.\n\nHowever, the task is only deceptively simple. At this point in time there are still basic disagreements as to what constitutes proper decomposition of a system. There are basic questions on how to document a design to provide design visibility. But more important, there is no established evaluation criteria to say whether or not a design is good. Establishing these principles is an integral part of the proposed tasks.\n\nThese are critical tasks to be addressed by NASA. Failure to do so will foreclose an opportunity to alleviate the continued high cost of software systems of questionable reliability.\n\nCost of these studies could range from low (3 man years) to medium (10 man years).\n### SOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET\n\n#### Trend Toward S/W Development\n\n<p>| | |</p>\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>1.</strong> Technology Driver:</td>\n<td>by Non-Programmers</td>\n</tr>\n<tr>\n<td><strong>2.</strong> Technology Category:</td>\n<td>Software Development</td>\n</tr>\n<tr>\n<td><strong>3.</strong> Missions Affected:</td>\n<td>All</td>\n</tr>\n<tr>\n<td><strong>4.</strong> Impact Date:</td>\n<td>1978</td>\n</tr>\n</tbody>\n</table>\n\n### Driver Description:\nWith the advent of microprocessor technology in highly distributed processing systems, more and more programming is performed by professional people with no background in programming skills. The programs are preponderantly coded in assembly or even machine language, and are usually unique, single-copy logic (i.e., each is a \"new\" invention). This trend will continue, and probably at an accelerated rate, along with its attendant high cost, inefficiency and retraining requirements, unless tools are provided for these systems. The tools required are standard operating systems, high level languages and scientific and mathematical subroutine packages for microcomputers. These tools will allow the individual scientist or engineer to generate reliable software more easily and at a lower cost.\n\n### Applicability to Payloads:\nThe low cost, volume, weight, and power requirements of microprocessors make them ideal candidates for space systems. These attributes enable new concepts of payload technology to be realized through the distribution and partitioning of functions. Unfortunately, the proliferation of computers expands the need for software and software costs are still rising. The promise of this new technology will not be fully achieved unless ways and means of controlling or limiting software cost can be found.\n\n### Current Technology Efforts:\nAvailable memory on microprocessors has been a limiting factor in converting sophisticated software languages to their use. These limitations are gradually lessening, and industry is beginning to make available higher order languages (primarily FORTRAN) for microprocessor systems. There are also new language techniques, such as FORTH, available to simplify software development. However, very little has been done to standardize and provide off-the-shelf operating systems and software libraries.\nSOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET\n\n8. Current Problems: Microprocessor technology is still in a very evolutionary state (e.g., 4-bit to 8-bit to 16-bit word length). Peripherals are primitive and still expensive. Memory size, though increasing, still imposes limitations on the use of less efficient languages and sophisticated operating systems. In addition, quite often the users of micro (and even mini) systems cannot afford extensive programming staffs. The software now being generated is costly in any case, but much more so when done by non-programmers.\n\n9. Technology Advancements Required: A number of technology advancements are needed to alleviate cost and improve reliability of software created by non-programmers. This is particularly critical to NASA in supporting the rapidly expanding use of space systems. These advancements are possible but need a central, coordinated thrust to achieve fruition. The key to solving current problems is to make programs and programming simpler. The following Technology Items are designed to do that:\n\n- Development of requirements-to-code translation aids.\n- Implementation of a simplified software development system demonstration model.\n- Research into query guided implementation methods.\n- Classification of error mechanisms.\n\nThese are achievable items and achievable at modest cost. Growing support of industry (not just the computer industry) is evident; however, in most cases the efforts at technology advancement is aimed at specific applications which will not satisfy the requirements of the space user community; therefore, NASA should initiate action to pursue these items. Failure to do so will limit the opportunity to slow the continued spiral of software cost and enhance software reliability.\nSOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET\n\n<table>\n<thead>\n<tr>\n<th>1. Technology Driver: Fault Free Software</th>\n<th>No. PS-03</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2. Technology Category: Software Development</td>\n<td></td>\n</tr>\n<tr>\n<td>3. Missions Affected: All</td>\n<td></td>\n</tr>\n<tr>\n<td>4. Impact Date: 1978</td>\n<td></td>\n</tr>\n<tr>\n<td>5. Driver Description: Software reliability (or unreliability) is a subject of universal concern, but it is an overriding concern for space flight particularly on longlife, autonomous missions. Fault free software is software that is correct and its internal data contains no errors. This does not necessarily equate to system reliability for the software is still subject to external data and machine errors; however, it definitely removes software per se as a cause of system unreliability.</td>\n<td></td>\n</tr>\n<tr>\n<td>6. Applicability to Payloads: Dependable systems are mandatory for Space applications and systems are never more dependable than their weakest component part. Software is a unique component of these systems because it is so difficult to predict where or when it might fail; conversely, if it could be completely "proven," it would never fail. This is what NASA should strive for.</td>\n<td></td>\n</tr>\n<tr>\n<td>7. Current Technology Efforts: As software reliability is of universal concern, the search for fault free software is a universal activity. Many avenues are being explored in the development of new and improved testing techniques, better requirements and design approaches, mathematical theory and management practices. Even computer architecture is evolving which aids in the prevention of software errors, but with all this activity truly fault-free software is hard to find.</td>\n<td></td>\n</tr>\n<tr>\n<td>8. Current Major Problems: The basic problem to be solved is how to develop adequate Software Engineering Techniques. Of course, other problems exist in areas such as validation/verification, lack of requirements and lack of standardization, but these will probably never be solved until Software Engineering comes of age.</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nSheet 1 of 3\n9. Technology Advancements Required: First and foremost, the development and dispersion of Software Engineering Technology. This should be accompanied by advances in other areas:\n\n- Consistency testing techniques to prove that design reflects requirements.\n- Automatic test case generators.\n- Integration and traceability techniques.\n- Study of error mechanisms.\n- Static and dynamic code checks in higher order languages.\n- Program proving aids and theory.\n- Improved quality assurance techniques.\n- Software redundancy techniques.\n- Computer architecture refinements.\n\nMost of these areas are being addressed both within NASA and outside, as for example SSES of NASA-MSFC. However, there is one additional area of significance that only NASA can address. This item is standardization. Standardization has many implications. It implies standard languages, standard operating systems, standard interface implementations and consistent management practices. Not all of NASA software can be standardized, but that, which can, should be identified and placed under rigid configuration control.\n\nOne characteristic that software evinces is the fact that the probability of a failure happening is proportional to the number of errors that exist in a program. Consequently, as failures occur and errors are removed over a span of time, the more reliable the software becomes, until theoretically it becomes fault-free. This is one of the unique and valuable assets provided by standardization. The use of standard functions multiplies the opportunity to exercise the code and allows it to be exercised in many different environments. Though a standard function may not initially be fault-free, given time it will certainly approach a fault-free state.\nStandard functions for aerospace applications can be identified and developed. There is virtually no support of standard aerospace software functions within the industry. Therefore, one Software Technology Item that NASA should address is:\n\n- Development of standardization criteria for NASA software.\n\nCost will vary with the degree of standardization, but total future software development cost would be significantly reduced. This area will also be aided indirectly by the technology item - classification of error mechanisms identified previously under PS-02.\n\nFailure to standardize will be expensive and prolong the risk of catastrophic failure due to software error.\n<p>| | |</p>\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>1. Technology Driver:</strong> AOL Design Methodology</td>\n<td>No. PS-04</td>\n</tr>\n<tr>\n<td><strong>2. Technology Category:</strong> Software Development</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>3. Missions Affected:</strong> All</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>4. Impact Date:</strong> 1978</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>5. Driver Description:</strong> A shift to an increased emphasis on application-oriented languages must be anticipated. This is due to the growing number of engineers (as opposed to professional programmers) developing or writing programs. Language design is one of those typical software areas which have no real guidelines, standards, or evaluation criteria which can aid in the quick development of high order languages. Language design is frequently a costly process of long duration; therefore, the development of an application-oriented language design methodology must be considered as a NASA goal.</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>6. Applicability to Payloads:</strong> The broad dispersion of the space vehicle user community, coupled with the increasing number of programs being written by engineering personnel rather than professional programmers, will demand the development of application-oriented languages for writing space application software.</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>7. Current Technology Efforts:</strong> Virtually no technology efforts exist with the exception of work with extensible languages and compiler writing systems.</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>8. Current Major Problems:</strong> Compiler writing systems have not fully matured. Extensible languages, although a subject of interest for years, still have severe limitations and will probably never fulfill expectations. Current language design methodology is expensive. There is a need to discover what AOL requirements are and to discover how to get a good design.</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n9. Technology Advancement Required:\n\n- Definition of guidelines, standards and evaluation criteria for the development of higher order languages.\n\n- Development of concepts for the development of requirements of an AOL.\n\n- Development of language design concepts.\n\n- Development of problem language statement and analysis techniques.\n\n- Evaluation of adaptive HOL's and extensible languages.\n\n- Development of simple languages.\n\nEffort expended on these items will result in evolutionary advancement. It is doubtful that any major breakthroughs will be achieved. Nevertheless, whatever gains made would be of benefit to the user community and would tend to reduce costs and add to reliability.\n\nOne Software Technology Item that NASA should address is:\n\n- Development of AOL design guidelines/standards.\n\nFailure to expend this effort will impose higher than necessary software costs on users of space systems. Guidelines for Design Structure consistency identified under PS-01 as a technology item can also be expected to contribute towards AOL design methodology at least in an indirect sense.\nSOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET\n\n<table>\n<thead>\n<tr>\n<th>Sheet 1 of 2</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>1.</strong> Technology Driver: AOL Compilers</td>\n</tr>\n<tr>\n<td><strong>2.</strong> Technology Category: Software Development</td>\n</tr>\n<tr>\n<td><strong>3.</strong> Missions Affected: All</td>\n</tr>\n<tr>\n<td><strong>4.</strong> Impact Date: 1978</td>\n</tr>\n</tbody>\n</table>\n\n**5.** Driver Description: For each language and computer environment pair, a specially tailored compiler is necessary. Although considerable research and development effort has been expended, such compilers have remained as very expensive items. The potential proliferation of languages and computer systems obviously requires that these costs be decreased significantly. This Technology Driver is closely related to Technology Driver PS-04, but here the emphasis is on development cost reduction as opposed to design methodology.\n\n**6.** Applicability to Payloads: A convenient, low-cost method of generating applications-oriented languages is required to support the space system user community. This is particularly so for users who have limited or minimal resources to pursue space exploration. In addition, in terms of software reliability, there is a need to ensure consistency in the way in which AOL's are implemented.\n\n**7.** Current Technology Efforts: Primarily, these are limited to government-sponsored efforts to produce compiler writing systems, metacompilers and language translators. Some activity on extensible languages (mostly by Universities) and industrial application of new language technology (e.g., FORTH by FORTH, Inc.), has also been reported.\n\n**8.** Current Major Problems: Compiler writing systems have not fully matured. Language translators have been found to be difficult and expensive to build and are not as universal as had been hoped. Extensible languages have not fulfilled expectations and probably never will except for specific applications.\n9. Technology Advancement Required:\n\n- Advancements in intermediate language technology.\n- Identification of the principles for using directory techniques for development of AOL's.\n- Improvements to the technology of adaptive HOL's and extensive languages.\n- Continued development of compiler writing systems and language translators.\n\nEvolutionary improvement of these items will reduce cost of AOL's if the improvements are aimed at cost reduction. In general, though, the key items are to determine what the application-oriented language requirements really are and find out why compiler generators cost so much. The most critical item for NASA at this time (in addition to the one identified previously under PS-04) is:\n\n- Evaluation of AOL compiler generator cost factors.\n\nFailure to expend this effort will place added burden on the user community and perhaps close the door to those with limited resources.\n\nCost of pursuing this effort would be moderate (3 man years).\nSOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET\n\n<table>\n<thead>\n<tr>\n<th>Sheet 1 of 2</th>\n</tr>\n</thead>\n</table>\n\n1. **Technology Driver:** Interconnection Techniques \n **No.** PS-06\n\n2. **Technology Category:** Software Systems Architecture\n\n3. **Missions Affected:** All\n\n4. **Impact Date:** 1978\n\n5. **Driver Description:** A distributed system, as the term is used here, is a system which contains multiple processors, each with its own executive, performing dedicated functions as part of a single partitioned system, usually each housing its own main memory. The concept is not particularly novel. However, it is only recently, through the advent of microcomputers, that it has become eminently practical.\n\nA distributed system has two major advantages:\n\n- Simplified development/modification of the system.\n- Ability to perform parallel processing.\n\nSimplified development/modification of the system comes about through the relative independency of the subsystems. That is, the computer process becomes a more integral part of the subsystem to which it is assigned and thus it can be designed, adapted, and verified almost independent of the other subsystems; however, the system design as a whole does not become any simpler, only more flexible. The very flexibility may make the system design, or the choice of system design, more difficult. Any network of computers has, for the software as well as the hardware, the inherent problem of selecting interprocess communication techniques and selection of functions to be or not to be distributed. This is, generally, an ill-defined area and thus results in a Technology Driver.\n\n6. **Applicability to Payloads:** Virtually all future payloads will use distributed systems in one form or another, if they have computer systems at all. In addition, this concept will be the enabling function of intelligent instruments. System partitioning and interconnection techniques are particularly crucial in development of real-time systems.\n7. Current Technology Efforts: Distributed systems are not new and the rapid growth of this technology, made possible by the availability of low cost processors, has stimulated a great deal of research and study both within and without the industry. However, a disproportionate amount of this study has been directed at what the technology can be applied to as opposed to how to apply it. The Unified Data System research supported by NASA is a good example of the current technology efforts.\n\n8. Current Problems: Selecting interprocess communication techniques, identifying functions, and selecting those functions to be distributed present the major problems. However, development of user-oriented software development tools and methods must be faced to bring the cost of distributed system software down to an appropriate level. There is a critical need to develop rules and methods for decomposing systems for optimum and consistent partitioning.\n\n9. Technology Advancements Required:\n - Research into optimal task allocation and scheduling methods.\n - Development of control structures for implementing these schedules.\n - Development of techniques for concurrent processes.\n - Development of NASA-oriented functional hardware/software interface technology.\n\n There are two items arising from these areas which must be accomplished by NASA. These are:\n\n - Development of interface criteria for NASA distributed processor applications.\n - Development of task control structures for distributed environments.\n\n Cost of these efforts will be modest (3-6 man years each). Failure to pursue these items will severely jeopardize the potential inherent in distributed system applications. This facet of Software Engineering is also furthered by decomposition and structuring guidelines identified earlier as a technology item under PS-01.\n**SOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET**\n\n<table>\n<thead>\n<tr>\n<th>Sheet 1 of 2</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Very Large Storage</strong></td>\n</tr>\n<tr>\n<td>1. Technology Driver: Access Simplification</td>\n</tr>\n<tr>\n<td>2. Technology Category: Software System Architecture</td>\n</tr>\n<tr>\n<td>3. Missions Affected: Imaging Missions, Autonomous Missions</td>\n</tr>\n<tr>\n<td>4. Impact Date: 1985</td>\n</tr>\n<tr>\n<td>5. Driver Description: A hardware technology that is associated with the availability of low-cost computers, but currently lagging is the availability of low-cost, large, rapid-access storage. Accessing such memories and using them effectively is currently a specialized software area. To enable non-programmers to use such storage devices on a routine basis requires some method of simplifying their use.</td>\n</tr>\n<tr>\n<td>6. Applicability to Payloads: With the advent of a data explosion, particularly in Earth and ocean observation, the need for image preprocessing and onboard classification is very real. In addition, deep space, autonomous payloads will demand high level data compression onboard. These processing functions require very large storage capability for the manipulation of large single and multidimensional arrays, intermediate storage (buffering) and reference data.</td>\n</tr>\n<tr>\n<td>7. Current Technology Efforts: Research in data base technology is very expensive and theoretical research is beginning to decrease. However, within the industry, a considerable effort is being invested on the development of improved access methods, more efficient control and recovery techniques and data structures. The most recent data base technology has been directed toward the development of relational data bases as opposed to hierarchical or network approaches. These efforts are directed at large ground systems and do not particularly apply to the class of use envisioned for space applications. There is literally no research or study directed toward the application of very large storage systems for onboard applications, nor is there any study as to how these systems would be used even if they were available.</td>\n</tr>\n<tr>\n<td>8. Current Major Problems: Although data utility constitutes a vitally important area for the future space applications, it presents problems so complex that they are even hard to state. Very little data exists</td>\n</tr>\n</tbody>\n</table>\nSOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET\n\n<table>\n<thead>\n<tr>\n<th>No.</th>\n<th>PS-07 Sheet 2 of 2</th>\n</tr>\n</thead>\n</table>\n\n8. (Cont'd) on the definition and use of these systems. Little is known about how the data structures are defined, how they are to be accessed, and precisely how they will be used. There has been very little research into large storage devices for real-time onboard systems.\n\n9. Technology Advancements Required: There are many areas in which technology development should begin. The more important of these are:\n - Develop techniques for representing data structures in computer-aided software design.\n - Develop structure techniques that will support high rate processing.\n - Develop techniques for data base sharing in distributed systems.\n - Develop concepts for parallel access methods.\n - Develop concepts to enhance data independence.\n - Evaluate the use of data storage preprocessors.\n - Identify error confinement and recovery techniques.\n\nThese items are important; however, except for research into real-time onboard systems (which is a hardware gated technology) it is felt that at this time all these areas are adequately addressed. NASA should monitor the technology advancements in these areas so as to be able to apply this technology when hardware for space systems becomes available. Accordingly, this monitoring becomes the main technology item here. However, this item is common to other areas across the board as shown in the technology driver-item correlation table.\n<table>\n<thead>\n<tr>\n<th></th>\n<th>SOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1.</td>\n<td>Technology Driver: Software Fault Detection</td>\n</tr>\n<tr>\n<td>2.</td>\n<td>Technology Category:</td>\n</tr>\n<tr>\n<td>3.</td>\n<td>Missions Affected: All</td>\n</tr>\n<tr>\n<td>4.</td>\n<td>Impact Date: 1980</td>\n</tr>\n<tr>\n<td>5.</td>\n<td>Driver Description: It may, for various reasons, never be truly feasible to provide absolute proof of software correctness. It therefore behooves us to study an alternate means of preventing the software from causing a system failure. This approach is detection of software failures during execution. It is not clear if and how this is truly feasible; nevertheless, it is the only currently known alternative and must therefore be listed as a Technology Driver. Fault detection is critical for two major reasons:</td>\n</tr>\n<tr>\n<td></td>\n<td>o Confinement of damage, and</td>\n</tr>\n<tr>\n<td></td>\n<td>o Enablement of recovery.</td>\n</tr>\n<tr>\n<td></td>\n<td>The more critical a function the greater is the need for fault detection capability.</td>\n</tr>\n<tr>\n<td>6.</td>\n<td>Applicability to Payloads: Real-time applications are particularly demanding of software reliability. The output must be correct the first time and on time. Typical of these applications is guidance and control of spacecraft, and in some cases the collection, processing, and distribution of data. Software failures can cause immediate, significant losses and have been known to do so in the past. In any event, even if failure cannot be prevented, early detection can help to minimize losses and in some cases pave the way to error correction. This certainly has implications for future payloads.</td>\n</tr>\n<tr>\n<td>7.</td>\n<td>Current Technology Efforts: To date, most failure detection technology has concentrated on hardware methods such as microdiagnostics, on-line diagnostics, parity checkers, comparaters and watchdog timers. The only real software error detectors have fallen into the category of error detection/correction codes, sum-checks and reasonableness tests. Just recently, industry has begun theoretical research into error mechanisms, software redundancy techniques and sophisticated error logic within</td>\n</tr>\n</tbody>\n</table>\nsoftware structures. There has been virtually no attempt to use (Cont'd) these concepts in practical applications.\n\n**8. Current Problems:** It is difficult if not impossible to suspend processing at the point at which a failure occurs. Usually several instructions will be executed after a failure and the results are unpredictable. There is no guaranty that an error will not also invalidate proper operation of the error detection software. Redundant software is costly both in life cycle cost and in system overhead.\n\n**9. Technology Advancements Required:** It is difficult to see specific technology advancements to improve software fault detection methods; however, a better understanding of error mechanisms should lead to better predictability of how and where errors are likely to occur. The most significant gains will probably come through improved computer architecture. Isolation of processes (modules, sub-functions, etc.) must be improved to at least limit the damage when an error does occur. In general, following good programming practices - knowing and understanding the relationship of inputs to outputs - will do more for error detection than perhaps any other facet of software technology. Some items currently under consideration by industry are:\n\n- Fault criteria determination.\n- Reasonableness testing concepts.\n- Software redundancy voting techniques.\n- Analysis of error mechanisms.\n\nOf these, the one item (already identified as a Software Technology Item under PS-02) of major significance here is:\n\n- Research into the classification of error mechanisms. (Items identified under PS-01 are also applicable to solution of the error detection problem.)\n9. The cost of this research will be moderate (3-6 man years). Documented errors from previous space programs should be used to consolidate these errors as a whole in order to throw new light on where errors occur and why they occurred.\n\nFailure to pursue this study will limit the application of industrial developed technology advancements to NASA space systems.\n## Software Technology Item Derivation Worksheet\n\n### 1. Technology Driver: Fault Detection\n\n#### 2. Technology Category: Software Systems Architecture\n\n#### 3. Missions Affected: All\n\n#### 4. Impact Date: 1980\n\n#### 5. Driver Description: Associated with the problem of fault detection is the problem of fault correction and recovery. In many hardware schemes, and in all known software schemes of fault detection, one or more instructions have been executed by the time a fault is detected. Recovery from such unwanted instruction execution is still an unsolved problem and must therefore still be considered a Technology Driver.\n\n#### 6. Applicability to Payloads: Software recovery techniques after error detection are very much applicable to payload software particularly in view of the fact that most of this software falls in the category of real-time systems. The ability to recover from error could make the difference between success or failure of a space mission.\n\n#### 7. Current Technology Efforts: Active research in software recovery techniques basically consists of attempts to improve older technologies such as checkpoint/restart or to impose proven hardware reliability concepts (like redundancy) on software. The newer concepts include a technique using recovery blocks which contain needed variable data and alternate processing algorithms, reconfiguration and retry (made possible by new low cost hardware), and system designs that provide small tightly closed environments. All of these approaches add considerable system overhead.\n\n#### 8. Current Major Problems: It is very difficult, if not impossible, to determine what happens between the time an error occurs and the time it is detected. This prevents acquiring a precise knowledge as to how far the process must back track (or to what hierarchical level) in order to fully recover. Overhead is too high to support most real time functions without excessive loss of data on error occurrence.\n9. Technology Advancements Required: A number of new technology advancements are required for this relatively undeveloped field. These include:\n\n- Control structures for dynamic software reconfiguration.\n- Development of software techniques to back up or mask hardware failure.\n- Development of techniques for restoring data integrity.\n- Development of techniques for identification of easily recoverable checkpoints.\n\nThese areas are getting more and more emphasis not only within NASA but also in industrial and university research; however, NASA should concentrate on an item of key importance to space applications. This is:\n\n- Develop program organization methods for real-time fault recovery.\n\nCost of this research will be at a moderate level although extended in time (3-6 people for 3-5 years).\n\nLack of effective recovery in real time space activity constantly places missions in jeopardy or requires sophisticated and expensive redundant hardware systems. The cause of recovery techniques will be advanced to some extent by the classification of error mechanisms identified in PS-02 and the structuring guidelines identified in PS-01.\n1. Technology Driver: High Speed Buffering Techniques\n\n2. Technology Category: Software System Architecture\n\n3. Missions Affected: High Data Rate Imaging Missions\n\n4. Impact Date: 1983\n\n5. Technology Driver Description: The very high data rates expected in the future missions (involving acquisition of multispectral image data over vast areas) which are beyond the capability of present day onboard computational resources, calls for large buffers and consequently high speed buffering techniques is viewed as a technology driver in meeting the requirements of data acquisition and processing on such missions.\n\n6. Applicability to Payloads: This is mainly applicable to missions involving high data rate imaging experiments.\n\n7. Current Technology Efforts: Buffering techniques are currently under study from various viewpoints, most important of which is that of its role in a communication based computer system. These studies include methods of core allocation and associated problems in queuing theory, etc. Related efforts in hardware technology areas in terms of advancements in storage techniques are also under progress.\n\n8. Current Major Problems: The needs of the high volume data experiments of imagery acquisition and analysis cannot be easily met with the current levels of buffering capacities in terms of size and speed and as such high speed buffering techniques tailored to the qualitative and quantitative aspects of onboard image analysis experiments are called for here.\n\n9. Technology Advancements Required: The efforts required to meet these needs can be summarized as studies aimed towards the development of:\n\n - Adaptive high speed buffering techniques for deployment in dynamic networks.\n\n Included within the scope of these studies will be topics such as store\nand forward techniques, data aging, and other related aspects (such as change detection) in the context of image acquisition and analysis, and processor architecture and peripherals characteristics (such as use of natural communication networks) effects on high speed buffering techniques.\n\nThese efforts, expected to be in the neighborhood of 3-5 man years, are considered essential for achieving onboard image acquisition and analysis capabilities at the data rates projected for future missions by the OFS Study. Supportive efforts include monitoring of development in allied fields such as processor architecture and advanced storage techniques which are likely to influence the proposed technology efforts.\n### SOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET\n\n**Design and Control of Adaptive Technology**\n\n<p>| | |</p>\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. Technology Driver: Software Procedures</td>\n<td>No. PS-11</td>\n</tr>\n<tr>\n<td>2. Technology Category: Software System Architecture</td>\n<td>Advanced missions involving some level of automated intelligence activities</td>\n</tr>\n<tr>\n<td>3. Missions Affected: intelligence activities</td>\n<td></td>\n</tr>\n<tr>\n<td>4. Impact Date:</td>\n<td>1988</td>\n</tr>\n</tbody>\n</table>\n\n5. **Driver Description:** The software procedures associated with automated intelligence, scene analysis, image processing and pattern recognition activities are numerous in number and complex in their interactions. Depending on the specific problem environment, these need to be put together in different combinations and configurations. The configurations are determined by the human in the loop on the basis of intermediate results during the processing. However, in automated intelligence environments, this adaptive selection and implementation of specific processing logic modules has to be incorporated into the software system as an integral part of the system. The design and control of adaptive software procedures is hence a driver for accomplishing these automated intelligence objectives.\n\n6. **Applicability to Payloads:** Mainly, this affects payloads expected to operate in deep space unmanned missions in ill-defined environments.\n\n7. **Current Technology Efforts:** Most software technology efforts in the areas of automated intelligence, image processing and scene analysis, have concentrated on the development of specific software to perform well defined individual tasks with a human in the loop dictating the adaptive selection of these specific software in the dynamic environment. Few reported efforts are available on the problem of integration of these software procedures into a system with adaptive capabilities.\n\n8. **Current Major Problems:** The areas of automated intelligence itself being in an embryonic stage, the system concepts are not yet fully developed and the requirements are not well defined. The problem is therefore to develop a fuller understanding of the objectives and requirements of the software system needed to support such activity followed by efforts at developing the means of meeting these requirements.\n9. Technology Advancements Required: Much of the efforts needed in this area being still at conceptual levels, the initial effort should be:\n\n- Definition and development of the control structure concepts for adaptive software procedures.\n\nOther efforts which can advance the cause of this study are development of techniques for adaptive assembly of microprocedures and dynamic path strategy selection as required in PS-10 and PS-13.\n\nThese advancements are deemed to be basic to the successful operation of deep space unmanned exploratory missions planned for the next decade and are likely to involve 3-5 man years. Supporting activities include monitoring of the developments in the overall area of automated intelligence.\n### SOFTWARE TECHNOLOGY ITEM DERIVATION WORKSHEET\n\n<table>\n<thead>\n<tr>\n<th>Sheet 1 of 2</th>\n</tr>\n</thead>\n</table>\n\n<p>| | |</p>\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. Technology Driver: Natural Communication Methods</td>\n<td>No. PS-12</td>\n</tr>\n<tr>\n<td>2. Technology Category: Software Applications/System Architecture</td>\n<td></td>\n</tr>\n<tr>\n<td>3. Missions Affected: All Manned Missions</td>\n<td></td>\n</tr>\n<tr>\n<td>4. Impact Date: 1980</td>\n<td></td>\n</tr>\n<tr>\n<td>5. Driver Description: In view of the naturally severe constraints on the availability of human resources in space environments, it is essential to make full use of the potential of the available resources. It is therefore advisable to provide for all possible natural communication methods to enhance the capabilities of human interaction with the computer system for all command and control type of activities. This enables maximum utilization of all the faculties at the command of the human operator. Exploration of the scope of natural communication methods in space environments is therefore a technology driver in achieving maximum utilization of man-machine systems.</td>\n<td></td>\n</tr>\n<tr>\n<td>6. Applicability to Payloads: This is mainly applicable to those involving human monitoring or performing of multiple operations which thereby place a heavy demand on human resources.</td>\n<td></td>\n</tr>\n<tr>\n<td>7. Current Technology Efforts: Use of natural communication methods between man and machine is indeed a popular area of industrial investigations. However, the needs of space applications as well as the associated constraints are not the same. Detailed studies of this aspect except perhaps for specific mission requirements, have not been reported. Further, the use of the natural communication methods is bound to affect the payload software system characteristics and this needs to be studied in depth.</td>\n<td></td>\n</tr>\n<tr>\n<td>8. Current Major Problems: The first problem is that no comprehensive study of the needs for natural communication methods in space environments is available. Such a study if carried out can identify the specific types of communication methods of value in space environments. Use of such natural communication methods will have to be integrated within the payload software system and this represents the major software related problem of concern here.</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nB-28\n9. Technology Advancements Required: The needs of this technology driver is best served by a preliminary study to identify the specific natural communication methods of significance in space environments. This can be accomplished by a review of both the needs for natural communication methods in space environments and the spectrum of natural communication methods known to be successful in other environments. This is then to be followed by a software technology related study whose objective will be:\n\n- Impacts of natural communication methods on NASA payload systems.\n\nThis is viewed as an indispensible development for the success of future complex manned missions involving ordinary civilian personnel and is expected to involve about 2 to 3 man years of effort. In addition, this effort should be supported by a monitoring activity of the developments in man-machine natural communication methods such as voice communication (recognition) techniques and containment of storage density for voice patterns.\n**Efficient Large Array Search**\n\n1. **Technology Driver:** and Sort Procedures \n **No.** PS-13\n\n2. **Technology Category:** Software Applications/System Architecture \n All those involving pattern classification of multi-spectral image.\n\n3. **Missions Affected:**\n\n4. **Impact Date:** 1985\n\n5. **Driver Description:** Many pattern classification software techniques involve table look up procedures with large arrays (tables) for efficient implementation. This, in turn, involves use of search and sort procedures in the table formulation and look up phases. In view of the expected high data rates in image applications and consequent need for high speed (repeated) table look up operations, it is desirable to achieve maximum efficiency in these operations. This will help in gaining considerable savings in computer resources requirements and will facilitate real time onboard implementation of these classification software. Accordingly the need for efficient search and sort procedures is considered a technology driver. Further, this will also be of concern in NASA software standardization.\n\n6. **Applicability to Payloads:** This is of particular significance in all payloads wherein pattern classification (of large volumes of multi-spectral data) is called for by the experimental objectives.\n\n7. **Current Technology Efforts:** Very many search and sort procedures have been reported in the literature mainly in the context of their application in operating system software. However, the needs and constraints as well as the array data characteristics are not necessarily the same in these applications. Very little effort in tailoring or restructuring these methods to the needs of pattern classification problems has been reported.\n\n8. **Current Major Problems:** The major problem is the need for computationally more efficient search and sort software procedures specifically designed to meet the requirements of the pattern classification algorithms environment, which in addition, are adaptive to array data characteristics.\n9. Technology Advancements Required: The major effort required can be stated as:\n\n- Development of adaptive search and sort procedures.\n\nThis can be accomplished by a planned organization of the following activities: (1) review of all reported search and sort procedures to assess their relevance and applicability to pattern classification algorithms environment, (2) selection and assessment of candidate techniques in the context of pattern classification at the expected data rates of payload experiments, (3) study of the interrelationships of search and sort procedures with data storage/retrieval techniques and processor architecture, (4) study of the feasibility of deriving adaptive procedures to make efficient use of the array data characteristics, (5) using the results of these different supporting studies, develop adaptive search and sort software techniques which are best suited to specific space system configurations and problem environments.\n\nThese developments, which can be expected to involve 2 to 3 man years of effort, are viewed as a prerequisite to onboard implementation of pattern classification and such other related software techniques which are needed for multispectral image data analysis experiments. In addition this will contribute towards NASA software standardization. As a supporting activity, NASA should monitor the development in pattern classification techniques particularly the table look up approaches to ensure that the proposed technology efforts are in step with other developments in the area.\n<table>\n<thead>\n<tr>\n<th>Technology Driver: Parallel Processing Techniques</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>No. PS-14</strong></td>\n</tr>\n<tr>\n<td><strong>Technology Category: Software Applications/Software Architecture</strong></td>\n</tr>\n<tr>\n<td><strong>Missions Affected: All involving image analysis.</strong></td>\n</tr>\n<tr>\n<td><strong>Impact Date: 1983</strong></td>\n</tr>\n</tbody>\n</table>\n\n5. **Driver Description:** Many of the image processing, pattern recognition and scene analysis functions in the context of image data analysis and automated intelligence activities can be visualized as a set of processing operations carried out independently on the different pixels in the image. Accordingly, these operations can be viewed as parallel processable instead of in sequence as is generally the case. While the concept of parallel processing is in itself not new, an indepth exploitation of this concept in the context of image processing functions is viewed as the technology driver, for achieving efficient use of computational resources onboard and facilitating onboard implementation of some of these functions which otherwise would be infeasible. This will also help in achieving standardization of software of concern to NASA.\n\n6. **Applicability to Payloads:** This is mainly applicable to the advanced mission payloads involving experiments of image acquisition and analysis.\n\n7. **Current Technology Efforts:** Parallel processing techniques are indeed a fairly active area of study. Most efforts are however in the general field of parallel processing and associated conceptual and hardware development. Very little of this effort is directed toward exploitation of this concept in implementing image processing techniques. While parallel processing implementations of particular algorithms have been attempted, no general study, which comprehensively explores the scope of parallel processing in the context of image data analysis, is known.\n\n8. **Current Major Problems:** The major problem is thus the need to apply available parallel processing concepts with necessary and desirable modifications to the entire spectrum of image processing algorithms to achieve maximum utilization of these concepts and thereby meet the severe demands of onboard image processing.\n9. Technology Advancements Required: The needs of this technology driver can be satisfied by:\n\n- Restructuring major software techniques (of relevance to NASA image processing and pattern recognition activities) for parallel processing.\n\nThis is accomplished by a prior review of major image processing and pattern recognition functions and algorithms to identify those which are \"parallel processable\" directly or through modifications.\n\nAnother associated effort of significance here (discussed earlier in PS-06) is that of optimal task allocation and scheduling and associated control structure development in the context of parallel processing environment.\n\nOther studies which would be beneficial include fault detection and recovery in parallel processing environments (through reconfiguration of parallel processor modules) and addressing problems of software synchronization. Accordingly progress in these areas have to be monitored by NASA.\n\nThese studies are necessary for accomplishing image acquisition and analysis onboard as required by the future imaging missions, and are likely to need 3-5 man years of effort.\nEfficient Large Array Manipulation\n\n1. Technology Driver: Procedures\n No. PS-15\n\n2. Technology Category: Software Applications/System Architecture\n\n3. Missions Affected: All Involving Image Analysis\n\n4. Impact Date: 1983\n\n5. Driver Description: Data Compression, Image processing and scene analysis functions often involve manipulation of large two (and sometimes three) dimensional data arrays, for example transposition of a large image matrix. This problem is non-trivial whenever the size of this array is too large to be held in core all at once. This obviously is the case when, say, we are processing an (1024 X 1024) image. Manipulations of such large arrays, being an integral part of many data compression and image processing procedures, is viewed accordingly as a technology driver.\n\n6. Applicability to Payloads: In view of the specialized nature of the problem, this affects mainly those payload missions which involve such image acquisition and analysis programs.\n\n7. Current Technology Efforts: There have been a few studies directly related to this problem of matrix transposition. Various alternatives have been proposed, most of which aim at reducing the number of transputs (inputs and outputs) required for transposing the matrix available externally in a sequential or random access storage device. However, the claims and counterclaims of these alternatives have not been evaluated. Another aspect which has been studied to some extent is that of reducing the size of the additional storage required for performing such transposition. There also exists a study aimed at investigating the problem of the so called optimal partitioning of the matrix to facilitate its manipulations. All of these efforts are only directed towards one or the other aspect of the problem in the context of large processing systems available on ground.\n\n8. Current Major Problems: The major problem is to make the manipulations of large two (or three) dimensional arrays practical on board, under the related constraints of time and computational resources such as core and external memory, for facilitating data compression, image processing and scene analysis activities.\n\nB-34\n9. Technology Advancements Required: Technology efforts are needed to\ndevelop a well defined procedure for optimal partitioning of the higher\ndimensional arrays, which will not only take into account (onboard)\ndata processing system configurations and constraints, but also\nexploit to the full extent the array data characteristics. This can\nbe achieved by a study of these different aspects: (1) feasibility of\ndevelopment of optimal partitioning procedures for two and three\ndimensional arrays under specified system constraints. (2) adapta-\nbility of array manipulation procedures to array characteristics.\n(3) interrelationships of array manipulation procedures with data\nstorage techniques and processor architecture.\n\nThese efforts (which will approximate to 2-3 man years) can be\nsummarized as a study for the development of\n\n- Optimal large array partitioning procedures.\n\nThis is very essential for onboard implementation of most data\ncompression and other image processing techniques of importance\nto multispectral image data analysis. In addition, the progress in the\narea of electronic cyclic memories (which has a definite bearing on\nproblems like matrix transposition) needs to be monitored by NASA\nto gain full advantage of the progress in hardware technology.\nAPPENDIX C\n\nCost/Time/Priority Assessment Worksheets\nThis appendix presents the Cost/Time/Priority assessment carried out for each of the technology items derived from the technology drivers under Phase II of the Study. Each item is described in terms of its objectives and goals, alternative solutions and related studies are identified, and NASA efforts, schedules, resources and priorities are assessed. These details are presented in the form of worksheets in this appendix.\n1. DESCRIPTION OF ITEM: Development of proper and consistent requirements decomposition and structuring guidelines for the design of real-time distributed systems for space applications. A major problem in the decomposition and structuring of software design is the lack of consistency from designer to designer. This makes it very difficult to identify proper design and almost impossible to evaluate software systems in any way, except in an empirical fashion after the software has been developed. This point in the cycle is too late. Errors detected after development are orders of magnitude more expensive to correct. This Technology Item seeks methods to eliminate this problem. Evaluation criteria for the designs and design consistency will have to be developed.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 3-4\n\n3. REQUIRED LEVEL: 6 DATE 1980\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 4\n\n5. ALTERNATIVE SOLUTIONS:\n (1) Development of requirements-to-code technology, thereby bypassing the design phase.\n (2) Utilization of automated design tools.\n\n6. RELATED ACTIVITIES:\n TI-08 Interface criteria for NASA distributed processor applications.\n TI-09 Task control structures for distributed processor environments.\n TI-18 Guidelines for design documentation consistency.\n TI-19 Software prototyping methods.\n\n7. RECOMMENDED NASA EFFORT: Initiate a study effort by calendar year 1978 to establish guidelines for decomposition methods. Couple this with development of evaluation criteria, structuring guidelines and design consistency guidelines to support activities from 1980 - 1990.\n\nESTIMATED DEVELOPMENT COSTS: $150K - $500K PRIORITY: 5\n\n8. SCHEDULE:\n - Requirements Decomposition Guidelines\n - Design Consistency Guidelines\n - Structuring Guidelines\n - Evaluation Criteria\nCOST/TIME/PRIORITY ASSESSMENT\n\nTITLE: Requirement-To-Code Translation Aids\n\n1. DESCRIPTION OF ITEM: Automated aids (such as RPG) are to be developed for translating well defined payload software requirements into program code (in the desired language). In effect, the translation aids may be looked upon as a set of master programs which output specific program codes corresponding to a given input of software requirements.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 2\n\n3. REQUIRED LEVEL: 6 DATE 1981\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 3-4\n\n5. ALTERNATIVE SOLUTIONS:\n - Continued use of the more expensive, error prone manual approach to translating into code the specified software requirements, is the only alternative available at the present time.\n - Query guided methods is another alternative being proposed as a parallel task (TI-04).\n\n6. RELATED ACTIVITIES:\n - TI-01 Requirements decomposition and structuring guidelines.\n - TI-03 Simplified software development system demonstration model.\n - TI-04 Query guided implementation methods.\n - TI-19 Software prototyping methods.\n\n7. RECOMMENDED NASA EFFORT: NASA efforts should be to initiate a study starting in 1978 to investigate the feasibility of development of these automated aids to meet NASA payload software requirements and follow it up with the development of such aids along the lines identified as feasible in the first stage of the study. The detailed schedule of this development is shown below.\n\nESTIMATED DEVELOPMENT COSTS: $500K - $1000K PRIORITY: 3\n\n8. SCHEDULE:\n - \n - State-of-the-art assessment\n - Payload software requirements identification\n - Master software instructions library development\n - Transformational approach development\n - Test and documentation\nTITLE: Simplified Software Development System Demonstration Model NO. TI-03\n\n1. DESCRIPTION OF ITEM: Creation of a demonstration model of a simplified software development system. This item is aimed at lowering the cost of software for users of microprocessors in distributed systems for real-time space operations. The demonstration model will be a precursor of low cost operational systems for non-programmer PI's.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 2\n\n3. REQUIRED LEVEL: 6 DATE 1981\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 3\n\n5. ALTERNATIVE SOLUTIONS:\n (1) Query-guided implementation methods.\n (2) Requirements-to-code translation aids.\n\n6. RELATED ACTIVITIES:\n TI-02 Requirements-to-code translation aids.\n TI-04 Query-guided implementation methods.\n TI-19 Software prototyping methods.\n\n7. RECOMMENDED NASA EFFORT: Begin requirements definition for a simplified software development system demonstration model in calendar year 1978. Schedule analysis, design, development and test such that a full year of evaluation can be accomplished in 1980. This will allow 2 years (1981-1982) for development of an operational system to support heavy space activity 1983 - 1990.\n\nESTIMATED DEVELOPMENT COSTS: $500K - $1000K PRIORITY: 3\n\n8. SCHEDULE:\n - Requirements Definition\n - Requirements Analysis\n - Demonstration Model System Design\n - Development and Test\n - Evaluation\n\nESTIMATED DEVELOPMENT COSTS:\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Cost</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n1. DESCRIPTION OF ITEM: New programming procedures have to be developed based on the idea of using a questionnaire approach to the programming task. The questionnaire approach helps in guiding the programmer through the different steps involved in his effort and thereby eliminates the errors of omission and reduces the errors of commission. An example of questionnaire approach would be the PSI Program Synthesis System (of Stanford University). Such an approach should be adapted to the needs of NASA payload software technology.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 2-3\n3. REQUIRED LEVEL: 6 DATE 1983\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 4\n\n5. ALTERNATIVE SOLUTIONS:\n - Use of the present day unguided manual approach involving considerable scope for both errors of omission and commission is the only available alternative.\n - The proposed Requirements-to-Code translation aid is a possible alternative but has yet to be practically demonstrated.\n\n6. RELATED ACTIVITIES:\n - TI-02 Requirements-to-Code translation aids.\n - TI-03 Simplified software development system demonstration model.\n - TI-19 Software prototyping methods.\n\n7. RECOMMENDED NASA EFFORT: The NASA effort required here spans the spectrum of NASA payload related software activities and is an R&D study to be initiated in 1978. The activity proposed here parallels the one proposed under TI-02 to some extent.\n\n8. SCHEDULE:\n - Requirements analysis\n - Software skeleton structure development\n - Questionnaire methodology development\n - Test and documentation\n\nESTIMATED DEVELOPMENT COSTS: $200K - $500K PRIORITY: 3\n**TITLE:** Standardization Criteria for NASA Software\n\n**NO.** TI-05\n\n1. **DESCRIPTION OF ITEM:** Standardization of NASA software is required to eliminate redundant development with its attendant cost and to improve long term software reliability. This item represents the first essential step in the standardization process (i.e., development of minimum standardization criteria). Standardization has many implications such as standard language design, standard operating system design, standard interface implementation and standard management practices; therefore, early development of criteria is mandatory. Standardized software is the easiest path to fault free software.\n\n2. **CURRENT STATUS OF TECHNOLOGY:** LEVEL\n\n3. **REQUIRED LEVEL:** DATE 1979\n\n4. **ESTIMATE OF NON-NASA ADVANCEMENT:** LEVEL\n\n5. **ALTERNATIVE SOLUTIONS:**\n\n None.\n\n6. **RELATED ACTIVITIES:**\n\n - TI-06 AOL design guidelines/standards.\n - TI-08 Interface criteria for NASA distributed processor applications.\n - TI-17 Classification of error mechanisms.\n - TI-19 Software prototyping methods.\n\n7. **RECOMMENDED NASA EFFORT:** Begin immediately an analysis of the full range of implications associated with standardization. Start development of criteria in mid 1978. Test the criteria by selecting candidate software packages and evaluating criteria validity in time to support accumulation of standard libraries in the 1980 - 1990 time frame.\n\n8. **SCHEDULE:**\n\n - Analysis of Standardization Implications\n - Development of Criteria\n - Identification of Candidates\n - Evaluation of Validity\n\n **ESTIMATED DEVELOPMENT COSTS:** $150K - $500K\n\n **PRIORITY:** 4\nCOST/TIME/PRIORITY ASSESSMENT\n\nTITLE: AOL Design Guidelines/Standards\n\n1. DESCRIPTION OF ITEM: A shift to an increased emphasis on application oriented languages must be anticipated. This is due to the growing number of engineers (as opposed to professional programmers) developing or writing programs. Thus a requirement exists to develop the capability to quickly and economically define application oriented languages. As an initial step, NASA needs to produce AOL design guidelines and standards to ensure language consistency and compatibility with real-time distributed space systems.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 3\n3. REQUIRED LEVEL: 6 DATE 1979\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 4\n\n5. ALTERNATIVE SOLUTIONS:\n (1) Use assembly language for applications.\n (2) Use a variety of currently available HOL's.\n Both of these options are expensive; each leads to significant integration problems; and both result in less than desirable reliability.\n\n6. RELATED ACTIVITIES:\n TI-01 Requirements decomposition and structuring guidelines.\n TI-05 Standardization criteria for NASA software.\n TI-07 AOL compiler generator cost factors.\n TI-08 Interface criteria for NASA distributed processor applications.\n\n7. RECOMMENDED NASA EFFORT: Begin, in 1978, to determine concepts for the development of requirements of AOL's. Follow this with the development of AOL design guidelines/standards and design evaluation criteria. This effort should be scheduled such that the guidelines/standards will be available before 1980. This will allow time to produce an operational AOL generator prior to the period of heavy development from 1983 - 1990.\n\nESTIMATED DEVELOPMENT COSTS: $100K - $250K PRIORITY: 3\n\n8. SCHEDULE:\n o AOL Requirements Concepts\n o AOL Design Guidelines/Standards\n o Design Evaluation Criteria\n1. DESCRIPTION OF ITEM: A compiler is needed for each language which will be designed and for each computer the language will be used for. Although considerable research and development effort has been expended, compilers remain as very expensive items. If these costs are ever to be reduced, an understanding of what the costs are and why they are so high must be reached. This Technology Item recommends a NASA study effort to determine these AOL cost factors.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 3\n\n3. REQUIRED LEVEL: 4 DATE 1978\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 3\n\n5. ALTERNATIVE SOLUTIONS: None\n\n6. RELATED ACTIVITIES:\n TI-06 AOL design guidelines/standards.\n\n7. RECOMMENDED NASA EFFORT: Initiate a study effort no later than calendar year 1978 to: (1) Identify representative AOL compiler generators, (2) Trace the development history of these generators, and (3) Perform a cost assessment of all major cost factors.\n\nESTIMATED DEVELOPMENT COSTS: $100K - $150K PRIORITY: 3\n\n8. SCHEDULE:\n - Typical AOL generators identification\n - Development history tracing\n - Cost assessment\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n**TITLE:** Interface Criteria for NASA Distributed Processor Applications\n\n1. **DESCRIPTION OF ITEM:** Virtually all future payloads will use distributed systems in one form or another. In addition, this concept will be the enabling function of intelligent instruments. System partitioning and interconnection techniques are particularly crucial in development of real-time systems. Any network of computers has, for the software as well as the hardware, the inherent problem of selecting interprocess communication techniques and selection of functions to be or not be distributed. This Technology Item (developing interface criteria for NASA distributed processor applications) represents a critical first step toward solving these problems.\n\n2. **CURRENT STATUS OF TECHNOLOGY:** LEVEL 2\n\n3. **REQUIRED LEVEL:** 6 DATE 1980\n\n4. **ESTIMATE OF NON-NASA ADVANCEMENT:** LEVEL 2\n\n5. **ALTERNATIVE SOLUTIONS:** Use of high cost non-standard interfaces. This alternative poses unmanageable integration problems.\n\n6. **RELATED ACTIVITIES:**\n - TI-01 Requirements decomposition and structuring guidelines.\n - TI-05 Standardization criteria for NASA software.\n - TI-09 Task control structures for distributed processor environments.\n - TI-10 Program organization methods for real-time fault recovery.\n - TI-12 Control structures for adaptive systems.\n\n7. **RECOMMENDED NASA EFFORT:** Begin studies to identify potential configurations and characterize data and control flow. Perform trades to select interprocess communication techniques and establish interface criteria for NASA distributed systems. This effort should begin as soon as possible and be scheduled for completion before 1980.\n\n8. **ESTIMATED DEVELOPMENT COSTS:** $100K - $200K\n\n<table>\n<thead>\n<tr>\n<th>PRIORITY: 10</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Identification of potential distributed configurations</td>\n</tr>\n<tr>\n<td>Data and control flow characterization</td>\n</tr>\n<tr>\n<td>Interprocess communication techniques selection</td>\n</tr>\n<tr>\n<td>Interface criteria</td>\n</tr>\n</tbody>\n</table>\nCOST/TIME/PRIORITY ASSESSMENT\n\nTITLE: Task Control Structures for Distributed Processor Environments NO. TI-09\n\n1. DESCRIPTION OF ITEM: Distributed systems (i.e., systems which contain multiple processors, each with its own executive, performing dedicated functions as part of a single partitioned system) are not new nor particularly novel. However, managing concurrent processes in real-time, space-oriented distributed systems is new. The criticality of proper operation is much higher than for ground-based systems. For this reason, NASA should begin to develop task control structures for distributed processors to simplify allocation, minimize communication and minimize interference.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 4\n\n3. REQUIRED LEVEL: 8 DATE 1981\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 4\n\n5. ALTERNATIVE SOLUTIONS: Adapt task control structures of ground-based systems. Risk entails the potential loss of efficiency and reliability required for space operations.\n\n6. RELATED ACTIVITIES:\n - TI-01 Requirements decomposition and structuring guidelines.\n - TI-05 Standardization criteria for NASA software.\n - TI-08 Interface criteria for NASA distributed processor applications.\n - TI-10 Program organization methods for real-time fault recovery.\n - TI-12 Control structures for adaptive systems.\n\n7. RECOMMENDED NASA EFFORT: NASA should begin no later than calendar 1978 to identify techniques for real-time concurrent processes and follow this with research into task allocation and scheduling methods. These two items will provide the basis for developing task control structures for real-time distributed systems. The goal should be to have these task control structures in an operational state by 1980.\n\n8. SCHEDULE:\n - Requirements analysis\n - Develop optimal task allocation and scheduling methods\n - Develop task control structures\n - Test and documentation\n\nESTIMATED DEVELOPMENT COSTS: $100K - $250K PRIORITY: 5\n1. **DESCRIPTION OF ITEM:** Lack of effective recovery in real-time space activity can endanger space missions. In the past this has been compensated for by using sophisticated (and expensive) redundant hardware systems. The main problem is that it is difficult (if not impossible) to determine what happens between the time an error occurs and the time it is detected. The objective of this Technology Item is to develop methods of program organization that would maintain status in a way to allow backup and recovery with minimum loss of data and control in real-time systems.\n\n2. **CURRENT STATUS OF TECHNOLOGY:** LEVEL 3\n\n3. **REQUIRED LEVEL:** 6 DATE 1982\n\n4. **ESTIMATE OF NON-NASA ADVANCEMENT:** LEVEL 4\n\n5. **ALTERNATIVE SOLUTIONS:**\n (1) Redundant systems with voting logic.\n (2) Fault free hardware/software.\n (3) Acceptance of risk.\n\n There are obvious drawbacks to each of these alternatives. Redundant systems are expensive and add significantly to power, weight and volume requirements. Fault free hardware/software has not been totally obtained and probably never will be. Risk may be acceptable for unmanned missions, but will presumably never be for manned spaceflight.\n\n6. **RELATED ACTIVITIES:**\n TI-01 Requirements decomposition and structuring guidelines.\n TI-09 Task control structures for distributed processor environments.\n TI-12 Control structures for adaptive systems.\n TI-17 Classification of error mechanisms.\n\n7. **RECOMMENDED NASA EFFORT:** NASA should begin research into the structure and organization of software systems designed to provide reliable fault recovery in real-time operations. The end goal is the development of appropriate program organization methods by 1982.\n\n8. **SCHEDULE:**\n - Real-time program structure analysis\n - Recovery techniques\n - Program organization methods\n\n **ESTIMATED DEVELOPMENT COSTS:** $200K - $1000K\n\n **PRIORITy:** 5\n1. DESCRIPTION OF ITEM: Advanced buffering techniques are to be developed for catering to the high data rates expected in the dynamic environments of the 1980's. These techniques should be capable of adapting themselves to the characteristics of the data environments to achieve optimal utilization of the available resources.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 2\n\n3. REQUIRED LEVEL: 8 DATE 1983\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 4\n\n5. ALTERNATIVE SOLUTIONS:\n - Continued use of present day techniques is an alternative which may however gate the expected high volume data acquisition and processing required in the future missions.\n - Significant orders of magnitude change in mass memory management might be another alternative.\n\n6. RELATED ACTIVITIES:\n None.\n\n7. RECOMMENDED NASA EFFORT: The effort to be undertaken by NASA to meet the requirements is a study (to be initiated in 1978) to assess the state-of-the-art in buffering techniques and related developments in computer architecture and other hardware technologies followed by the development of adaptive techniques capable of optimal utilization of these resources in dynamic environments.\n\nESTIMATED DEVELOPMENT COSTS: $250K - $750K PRIORITY: 2\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>State-of-the-art assessment</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Impact of advancements in related areas</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>New adaptive techniques development</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Implementation, testing and documentation</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nC-13\nTITLE: Control Structures for Adaptive Systems\n\n1. DESCRIPTION OF ITEM: Control structures are needed to adaptively deploy available software to meet the requirements of the automated intelligence environments. This dynamic restructuring of the software to adapt it to the environment will enable NASA to plan and execute missions involving considerable autonomous capabilities.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 2\n\n3. REQUIRED LEVEL: 6 DATE 1981\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 3-4\n\n5. ALTERNATIVE SOLUTIONS: The alternative is a software system that has little adaptability to the changing environment and incapable of supporting autonomous unmanned missions involving at least rudimentary automated intelligence.\n\n6. RELATED ACTIVITIES:\n TI-04 Query guided implementation methods.\n TI-05 Standardization criteria for NASA software.\n TI-09 Task control structures for distributed processor environments.\n TI-14 Adaptive search and sort procedures.\n TI-15 Restructured image analysis software for parallel processing.\n\n7. RECOMMENDED NASA EFFORT: NASA should initiate a study to develop appropriate techniques for real-time adaptive restructuring of software to meet the environmental requirements to ensure that the software technology stays ahead of the requirements of autonomously operated missions.\n\nESTIMATED DEVELOPMENT COSTS: $300K - $500K PRIORITY: 1\n\n8. SCHEDULE:\n - Identification of software function interdependencies and relationships\n - Adaptive control structures development\n - Testing and documentation\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Activity</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\nTITLE: Impacts of Natural Communication Methods on NASA Payload Systems\n\n1. DESCRIPTION OF ITEM: It is essential for the efficient usage of available human resources onboard that natural communication methods be used to the extent feasible. Accordingly it is necessary to evaluate their influence and potential impact on the supporting payload software system and thereby ensure the success of the deployment of such methods. Towards this end, typical implementation of natural communication methods onboard for specific experimental tasks should be studied and the results used to derive an overall assessment of the impact of these methods on NASA payload software design.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 2-3\n\n3. REQUIRED LEVEL: 6 DATE 1981\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 4\n\n5. ALTERNATIVE SOLUTIONS: Traditional methods of communication with the computers, when used exclusively, are not necessarily efficient in multiple task environments of future manned missions and are therefore a poor alternative to having natural communication methods as an added capability.\n\n6. RELATED ACTIVITIES:\n\n TI-08 Interface criteria for NASA distributed processor applications.\n\n7. RECOMMENDED NASA EFFORT: NASA efforts in this area should include an ongoing monitoring of the developments in natural communication methods and technology to take advantage of such capabilities as and when this becomes practical. This be should be accompanied by an assessment of their impact on NASA software requirements and design.\n\n ESTIMATED DEVELOPMENT COSTS: $150K - $250K\n\n PRIORITY: 1\n\n8. SCHEDULE:\n\n - NASA requirements for natural communication methods\n - Impact on NASA software requirements\n - Delineation of modifications to payload software system\n - Overall assessment of the impact of natural communication methods\n\n**COST/TIME/PRIORITY ASSESSMENT**\n\n**TITLE:** Adaptive Search and Sort Procedures \n**NO.** TI-14\n\n1. **DESCRIPTION OF ITEM:** Adaptive search and sort procedures are required to ensure that the deployment of pattern recognition, image processing and related algorithms will be efficient and enable processing the high volume data in near real time as required in future NASA missions. These routines should be adaptive to the data characteristics of the arrays being manipulated.\n\n2. **CURRENT STATUS OF TECHNOLOGY:** LEVEL 2\n\n3. **REQUIRED LEVEL:** 6 \n**DATE:** 1981\n\n4. **ESTIMATE OF NON-NASA ADVANCEMENT LEVEL:** LEVEL 3-4\n\n5. **ALTERNATIVE SOLUTIONS:** Use of non-standardized, arbitrarily picked search and sort routines currently available as parts of different pattern recognition and image processing packages, is an alternative involving duplication of software and inefficient routines not particularly suited to NASA requirements.\n\n6. **RELATED ACTIVITIES:**\n- TI-05 Standardization criteria for NASA software.\n- TI-12 Control structures for adaptive systems.\n- TI-15 Restructured image analysis software for parallel processing.\n- TI-16 Optimal large array partitioning procedures.\n\n7. **RECOMMENDED NASA EFFORT:** NASA should initiate a study to perform the requirement analysis for search and sort techniques in the context of image processing and pattern recognition activities and follow it up with development of appropriate adaptive search and sort routines to meet these requirements.\n\n**ESTIMATED DEVELOPMENT COSTS:** $150K - $250K \n**PRIORITY:** 1\n\n8. **SCHEDULE:**\n- Requirements Analysis\n- Adaptive routines and control structures development\n- Implementation, testing and documentation\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nC-16\n**COST/TIME/PRIORITY ASSESSMENT**\n\n**TITLE:** Restructured Image Analysis Software for Parallel Processing \n\n**1. DESCRIPTION OF ITEM:** Onboard image processing/pattern recognition can be enabled by restructuring the key software functions to achieve maximum parallel processability. This can be attained by identifying the parallelism in these functions and adapting a suitable computer architecture which will take full advantage of the advancements in low cost hardware technology and parallel processing concepts.\n\n**2. CURRENT STATUS OF TECHNOLOGY:** LEVEL 2-3\n\n**3. REQUIRED LEVEL:** 6 \n**DATE:** 1981\n\n**4. ESTIMATE OF NON-NASA ADVANCEMENT:** LEVEL 4\n\n**5. ALTERNATIVE SOLUTIONS:** Alternatives to restructuring image analysis software (for parallel processing) are:\n- To use the software as is in non-parallel processing environment.\n- To create new software expressly for parallel processing.\n- Develop image processing dedicated hardware.\n\nThe first two alternatives are either inefficient or unnecessarily expensive. The last needs further exploration.\n\n**6. RELATED ACTIVITIES:**\n- TI-05 Standardization criteria for NASA software.\n- TI-09 Task control structures for distributed processor environments.\n- TI-12 Control structure for adaptive systems.\n\n**7. RECOMMENDED NASA EFFORT:** NASA should direct its efforts towards enabling onboard image processing/pattern recognition functions through achievement of maximum parallelism in these processing activities. This is to be done through a study which will identify all the parallelism inherent in these functions not only in terms of parallel or concurrent identical processing on different pixels (data subsets) but also in terms of parallel execution of different computations on the same data.\n\n**ESTIMATED DEVELOPMENT COSTS:** $250K - $1000K \n**PRIORITY:** 7\n\n**8. SCHEDULE:**\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Parallel processible functions identification</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Restructuring/modification of image analysis</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Identification of computer architecture for implementing the restructured software system</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n1. DESCRIPTION OF ITEM: Optimal large array partitioning procedures offer a viable solution to the problems of large array manipulations such as matrix transpositions under the constraints of the processing system configurations expected onboard in the near future. Development of such procedures will enhance the capability of the processor in meeting the image processing requirements more effectively.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 2-3\n\n3. REQUIRED LEVEL: 6 DATE 1983\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 3-4\n\n5. ALTERNATIVE SOLUTIONS: Electronic cyclic memories can alleviate to a considerable extent the problem of large array manipulations such as matrix transposition. This alternative has only been conceptually visualized. But, practical solutions for onboard implementation have yet to be realized.\n\n6. RELATED ACTIVITIES:\n - TI-05 Standardization criteria for NASA software.\n - TI-12 Control structure for adaptive systems.\n - TI-14 Adaptive search and sort procedures.\n\n7. RECOMMENDED NASA EFFORT: It is necessary that NASA should initiate a study of the feasibility and development of optional procedures for large 2 and 3 dimensional arrays manipulations to meet the needs of data compression, image processing scene analysis problems.\n\nESTIMATED DEVELOPMENT COSTS: $150K - $250K PRIORITY: 1\n\n8. SCHEDULE:\n - Feasibility assessment for adapting array manipulation procedures to array data characteristics\n - Impact of data storage and processor architecture\n - Development, testing and documentation\n\n --- | --- | --- | --- | --- | --- | --- | --- | ---\n - | - | - | - | - | - | - | - | -\nClassification of Error Mechanisms\n\n1. DESCRIPTION OF ITEM: Study of past experience in software errors, their types, characteristics and frequency or likelihood helps in identifying the causes of such errors and leads to a reduction of the chances of their occurrence in future missions. Accordingly classification of the error mechanisms will enhance the cause of fault free software development.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 2-3\n\n3. REQUIRED LEVEL: 6 DATE 1980\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 4\n\n5. ALTERNATIVE SOLUTIONS: Fault tolerant software development, if feasible, is an alternative. However, in general, the study of error mechanism will aid this alternative also in addition to reducing the likelihood of such errors.\n\n6. RELATED ACTIVITIES:\n TI-10 Program organization methods for real-time fault recovery.\n TI-19 Software prototyping methods.\n\n7. RECOMMENDED NASA EFFORT: NASA efforts in this area should cover all recorded past software development activities to ensure that past experience will serve to enhance future performance. The tasks under this effort are as itemized below.\n\nESTIMATED DEVELOPMENT COSTS: $150K - $250K PRIORITY: 4\n\n8. SCHEDULE:\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Error data compilation</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Characteristics extraction</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>and modeling of the errors</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Error classification</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>New methodology feasibility assessment (for avoiding these errors)</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\nCOST/TIME/PRIORITY ASSESSMENT\n\nTITLE: Guidelines for Design Documentation Consistency\n\n1. **DESCRIPTION OF ITEM:** A major problem in the decomposition and restructuring of software design is the lack of a documentation methodology to accurately portray it. Many errors are introduced into programs during development, change and maintenance phases, because the programmer does not clearly understand the intent of the designer. This leads to much higher than required life-cycle costs and often results in less than reliable software. New methods of documentation, compatible with state-of-the-art design techniques, must be found.\n\n2. **CURRENT STATUS OF TECHNOLOGY:** LEVEL 3-4\n\n3. **REQUIRED LEVEL:** 8 DATE 1980\n\n4. **ESTIMATE OF NON-NASA ADVANCEMENT:** LEVEL 5\n\n5. **ALTERNATIVE SOLUTIONS:**\n\n None.\n\n6. **RELATED ACTIVITIES:**\n\n TI-01 Requirements decomposition and structuring guidelines.\n TI-05 Standardization criteria for NASA software.\n TI-06 AOL design guidelines/standards.\n\n7. **RECOMMENDED NASA EFFORT:** NASA should begin no later than calendar 1978 to develop methods of obtaining documentation consistency and from these methods generate guidelines to ensure consistency of future software development projects. In this way, documentation which clearly and concisely describes the problem and its solution, and which reflects program structure will be enabled.\n\n**ESTIMATED DEVELOPMENT COSTS:** $100K - $250K\n\n8. **SCHEDULE:**\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Design structure analysis</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Development of documentation guidelines</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Evaluation criteria</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\nCOST/TIME/PRIORITY ASSESSMENT\n\nTITLE: Software Prototyping Methods\n\n1. DESCRIPTION OF ITEM: Concern for the high cost of design errors during and after software development has led to a search for ways to proof a design before committing it to code. One of the more promising techniques recently receiving increased emphasis is software prototyping. Software prototyping is a method of testing the key elements of a design at minimal cost, prior to starting development of the operational system. This technique has been successfully used on a few ground based systems, but has yet to be applied to real-time space systems. The key to this Technology Item is development of true, low-cost prototyping techniques.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL 3\n\n3. REQUIRED LEVEL: 6 DATE 1980\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL 4\n\n5. ALTERNATIVE SOLUTIONS:\n (1) Requirements-to-code translation.\n (2) Consistent decomposition and structuring methods.\n (3) The two alternatives, although highly desirable goals, do not fully satisfy the problem, since neither gives a good indication of the feasibility or cost of committing the design to code, regardless of the quality of the design.\n\n6. RELATED ACTIVITIES:\n TI-03 Simplified software development system demonstration model.\n TI-05 Standardization criteria for NASA software.\n\n7. RECOMMENDED NASA EFFORT: NASA should begin research and development of real-time software prototyping. The cost savings on large development projects through ensuring design feasibility will far outweigh the cost of developing proofing methods and will lead to more reliable end products.\n\nESTIMATED DEVELOPMENT COSTS: $100K - $250K PRIORITY: 4\n\n8. SCHEDULE:\n - Technology analysis\n - Low-cost prototyping methods\n - Evaluation criteria\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\nTITLE: Software Technology Monitoring\n\n1. DESCRIPTION OF ITEM: Software technology is continually advancing, and though growth is primarily evolutionary, there is nothing to preclude a revolutionary breakthrough, particularly in view of the dramatic advances in hardware technology. NASA should be in a position to capitalize on all technology advances, whether achieved by government, in Universities, or in industry. It can best do this by establishing a mechanism to continually review state-of-the-art technology.\n\n2. CURRENT STATUS OF TECHNOLOGY: LEVEL N/A\n\n3. REQUIRED LEVEL: N/A DATE 1978-1990\n\n4. ESTIMATE OF NON-NASA ADVANCEMENT: LEVEL N/A\n\n5. ALTERNATIVE SOLUTIONS:\n\n None.\n\n6. RELATED ACTIVITIES:\n\n None.\n\n7. RECOMMENDED NASA EFFORT: NASA should establish a function to continually monitor state-of-the-art software technology. This function should project NASA needs, establish milestones for industrial advancement, and identify those areas where NASA must force progress. In this way, NASA will get full benefit of advances outside of the organization and at the same time be in a position to ensure that its requirements are met, at the time needed.\n\nESTIMATED DEVELOPMENT COSTS: $50K per year (1977 dollars) PRIORITY: 5\n\n8. SCHEDULE:\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n o Monitor software technology advances"}}},{"rowIdx":55,"cells":{"id":{"kind":"string","value":"6cd9befc5d594e11a03b357c4a8b552187de4830"},"text":{"kind":"string","value":"Abstract\n\nThis manual describes how to install and configure MySQL Connector/Python, a self-contained Python driver for communicating with MySQL servers, and how to use it to develop database applications.\n\nMySQL Connector/Python 8.0 is highly recommended for use with MySQL Server 8.0, 5.7, and 5.6. Please upgrade to MySQL Connector/Python 8.0.\n\nFor notes detailing the changes in each release of Connector/Python, see MySQL Connector/Python Release Notes.\n\nFor legal information, see the Legal Notices.\n\nFor help with using MySQL, please visit the MySQL Forums, where you can discuss your issues with other MySQL users.\n\nLicensing information. This product may include third-party software, used under license. MySQL Connector/Python 2.2 Community License Information User Manual has information about licenses relating to MySQL Connector/Python community releases up to and including version 2.2. MySQL Connector/Python 2.2 Commercial License Information User Manual has information about licenses relating to MySQL Connector/Python commercial releases up to and including version 2.2. MySQL Connector/Python 8.0 Community License Information User Manual has information about licenses relating to MySQL Connector/Python community releases in the 8.0 release series. MySQL Connector/Python 8.0 Commercial License Information User Manual has information about licenses relating to MySQL Connector/Python commercial releases in the 8.0 release series.\n\nDocument generated on: 2023-05-26 (revision: 75749)\n## Table of Contents\n\nPreface and Legal Notices ........................................................................................................... vii\n1 Introduction to MySQL Connector/Python ............................................................................ 1\n2 Guidelines for Python Developers .......................................................................................... 3\n3 Connector/Python Versions ..................................................................................................... 5\n4 Connector/Python Installation ............................................................................................... 7\n 4.1 Obtaining Connector/Python ............................................................................................ 8\n 4.2 Installing Connector/Python from a Binary Distribution ............................................... 8\n 4.3 Installing Connector/Python from a Source Distribution ............................................. 10\n 4.4 Verifying Your Connector/Python Installation ............................................................ 12\n5 Connector/Python Coding Examples ..................................................................................... 13\n 5.1 Connecting to MySQL Using Connector/Python ......................................................... 13\n 5.2 Creating Tables Using Connector/Python ...................................................................... 14\n 5.3 Inserting Data Using Connector/Python ........................................................................ 17\n 5.4 Querying Data Using Connector/Python ......................................................................... 18\n6 Connector/Python Tutorials .................................................................................................. 21\n 6.1 Tutorial: Raise Employee's Salary Using a Buffered Cursor ....................................... 21\n7 Connector/Python Connection Establishment ..................................................................... 23\n 7.1 Connector/Python Connection Arguments .................................................................... 23\n 7.2 Connector/Python Option-File Support ......................................................................... 30\n8 The Connector/Python C Extension ...................................................................................... 33\n 8.1 Application Development with the Connector/Python C Extension ............................ 33\n 8.2 The _mysql_connector C Extension Module .................................................................. 34\n9 Connector/Python Other Topics ........................................................................................... 35\n 9.1 Connector/Python Logging ........................................................................................... 35\n 9.2 Connector/Python Connection Pooling ......................................................................... 35\n 9.3 Connector/Python Django Back End .............................................................................. 37\n10 Connector/Python API Reference ....................................................................................... 39\n 10.1 mysql.connector Module ............................................................................................. 41\n 10.1.1 mysql.connector.connect() Method ................................................................. 41\n 10.1.2 mysql.connector.apilevel Property .................................................................... 41\n 10.1.3 mysql.connector.paramstyle Property ............................................................. 41\n 10.1.4 mysql.connector.threadsafety Property .......................................................... 42\n 10.1.5 mysql.connector.__version__ Property ........................................................... 42\n 10.1.6 mysql.connector.__version_info__ Property .................................................... 42\n 10.2 connection.MySQLConnection Class .......................................................................... 42\n 10.2.1 connection.MySQLConnection() Constructor ..................................................... 42\n 10.2.2 MySQLConnection.close() Method ................................................................. 42\n 10.2.3 MySQLConnection.commit() Method ............................................................... 43\n 10.2.4 MySQLConnection.config() Method ............................................................... 43\n 10.2.5 MySQLConnection.connect() Method ............................................................. 43\n 10.2.6 MySQLConnection.cursor() Method .................................................................. 44\n 10.2.7 MySQLConnection.cmd_change_user() Method ............................................ 44\n 10.2.8 MySQLConnection.cmd_debug() Method ........................................................ 45\n 10.2.9 MySQLConnection.cmd_init_db() Method ...................................................... 45\n 10.2.10 MySQLConnection.cmd_ping() Method ........................................................ 45\n 10.2.11 MySQLConnection.cmd_process_info() Method ........................................... 45\n 10.2.12 MySQLConnection.cmd_process_kill() Method ........................................... 45\n 10.2.13 MySQLConnection.cmd_query() Method ....................................................... 45\n 10.2.14 MySQLConnection.cmd_query_iter() Method .............................................. 46\n 10.2.15 MySQLConnection.cmd_quit() Method .......................................................... 46\n 10.2.16 MySQLConnection.cmd_refresh() Method .................................................... 46\n 10.2.17 MySQLConnection.cmd_reset_connection() Method .................................... 47\n 10.2.18 MySQLConnection.cmd_shutdown() Method ................................................ 47\n 10.2.19 MySQLConnection.cmd_statistics() Method ................................................. 47\n 10.2.20 MySQLConnection.disconnect() Method ....................................................... 47\n10.2.21 MySQLConnection.get_row() Method ..................................................... 47\n10.2.22 MySQLConnection.get_rows() Method ..................................................... 47\n10.2.23 MySQLConnection.get_server_info() Method ........................................... 48\n10.2.24 MySQLConnection.get_server_version() Method ..................................... 48\n10.2.25 MySQLConnection.is_connected() Method ............................................... 48\n10.2.26 MySQLConnection.isset_client_flag() Method ........................................ 48\n10.2.27 MySQLConnection.ping() Method .......................................................... 48\n10.2.28 MySQLConnection.reconnect() Method ................................................... 48\n10.2.29 MySQLConnection.reset_session() Method ............................................. 49\n10.2.30 MySQLConnection.rollback() Method ..................................................... 49\n10.2.31 MySQLConnection.set_charset_collation() Method ................................ 49\n10.2.32 MySQLConnection.set_client_flags() Method ......................................... 50\n10.2.33 MySQLConnection.shutdown() Method .................................................... 50\n10.2.34 MySQLConnection.start_transaction() Method ....................................... 50\n10.2.35 MySQLConnection.autocommit Property .................................................. 51\n10.2.36 MySQLConnection.unread_results Property ............................................ 51\n10.2.37 MySQLConnection.can_consume_results Property .................................... 51\n10.2.38 MySQLConnection.charset Property ...................................................... 51\n10.2.39 MySQLConnection.collation Property ..................................................... 51\n10.2.40 MySQLConnection.connection_id Property ............................................. 51\n10.2.41 MySQLConnection.database Property .................................................... 52\n10.2.42 MySQLConnection.get_warnings Property .............................................. 52\n10.2.43 MySQLConnection.in_transaction Property ............................................. 52\n10.2.44 MySQLConnection.raise_on_warnings Property ....................................... 52\n10.2.45 MySQLConnection.server_host Property ............................................... 53\n10.2.46 MySQLConnection.server_port Property ............................................... 53\n10.2.47 MySQLConnection.sql_mode Property .................................................... 53\n10.2.48 MySQLConnection.time_zone Property .................................................... 53\n10.2.49 MySQLConnection.unix_socket Property ................................................ 54\n10.2.50 MySQLConnection.user Property ......................................................... 54\n10.3 pooling.MySQLConnectionPool Class ......................................................... 54\n10.3.1 pooling.MySQLConnectionPool Constructor ............................................. 54\n10.3.2 MySQLConnectionPool.add_connection() Method ..................................... 54\n10.3.3 MySQLConnectionPool.get_connection() Method ..................................... 55\n10.3.4 MySQLConnectionPool.set_config() Method .......................................... 55\n10.3.5 MySQLConnectionPool.pool_name Property ............................................ 55\n10.4 pooling.PooledMySQLConnection Class ..................................................... 55\n10.4.1 pooling.PooledMySQLConnection Constructor ......................................... 56\n10.4.2 PooledMySQLConnection.close() Method ............................................... 56\n10.4.3 PooledMySQLConnection.config() Method ............................................. 56\n10.4.4 PooledMySQLConnection.pool_name Property ....................................... 56\n10.5 cursor.MySQLCursor Class ................................................................. 57\n10.5.1 cursor.MySQLCursor Constructor .......................................................... 57\n10.5.2 MySQLCursor.add_attribute() Method ................................................... 58\n10.5.3 MySQLCursor.clear_attributes() Method ................................................. 59\n10.5.4 MySQLCursor.get_attributes() Method ................................................... 59\n10.5.5 MySQLCursor.callproc() Method .......................................................... 59\n10.5.6 MySQLCursor.close() Method .............................................................. 60\n10.5.7 MySQLCursor.execute() Method .......................................................... 60\n10.5.8 MySQLCursor.executemany() Method ..................................................... 60\n10.5.9 MySQLCursor.fetchall() Method .......................................................... 61\n10.5.10 MySQLCursor.fetchall() Method ........................................................ 61\n10.5.11 MySQLCursor.fetchall() Method ........................................................ 62\n10.5.12 MySQLCursor.fetchone() Method ........................................................ 62\n10.5.13 MySQLCursor.stored_results() Method ............................................... 62\n10.5.14 MySQLCursor.column_names Property .................................................. 63\n10.5.15 MySQLCursor.description Property ..................................................... 63\n10.5.16 MySQLCursor.lastrowid Property ......................................................... 64\nPreface and Legal Notices\n\nThis manual describes how to install, configure, and develop database applications using MySQL Connector/Python, the Python driver for communicating with MySQL servers.\n\nLegal Notices\n\nCopyright © 2012, 2023, Oracle and/or its affiliates.\n\nThis software and related documentation are provided under a license agreement containing restrictions on use and disclosure and are protected by intellectual property laws. Except as expressly permitted in your license agreement or allowed by law, you may not use, copy, reproduce, translate, broadcast, modify, license, transmit, distribute, exhibit, perform, publish, or display any part, in any form, or by any means. Reverse engineering, disassembly, or decompilation of this software, unless required by law for interoperability, is prohibited.\n\nThe information contained herein is subject to change without notice and is not warranted to be error-free. If you find any errors, please report them to us in writing.\n\nIf this is software or related documentation that is delivered to the U.S. Government or anyone licensing it on behalf of the U.S. Government, then the following notice is applicable:\n\nU.S. GOVERNMENT END USERS: Oracle programs (including any operating system, integrated software, any programs embedded, installed or activated on delivered hardware, and modifications of such programs) and Oracle computer documentation or other Oracle data delivered to or accessed by U.S. Government end users are \"commercial computer software\" or \"commercial computer software documentation\" pursuant to the applicable Federal Acquisition Regulation and agency-specific supplemental regulations. 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If you use this software or hardware in dangerous applications, then you shall be responsible to take all appropriate fail-safe, backup, redundancy, and other measures to ensure its safe use. Oracle Corporation and its affiliates disclaim any liability for any damages caused by use of this software or hardware in dangerous applications.\n\nOracle, Java, and MySQL are registered trademarks of Oracle and/or its affiliates. Other names may be trademarks of their respective owners.\n\nIntel and Intel Inside are trademarks or registered trademarks of Intel Corporation. All SPARC trademarks are used under license and are trademarks or registered trademarks of SPARC International, Inc. AMD, Epyc, and the AMD logo are trademarks or registered trademarks of Advanced Micro Devices. UNIX is a registered trademark of The Open Group.\n\nThis software or hardware and documentation may provide access to or information about content, products, and services from third parties. Oracle Corporation and its affiliates are not responsible for and expressly disclaim all warranties of any kind with respect to third-party content, products, and services unless otherwise set forth in an applicable agreement between you and Oracle. Oracle Corporation and its affiliates will not be responsible for any loss, costs, or damages incurred due to your access to or use of third-party content, products, or services, except as set forth in an applicable agreement between you and Oracle.\n\nThis documentation is NOT distributed under a GPL license. Use of this documentation is subject to the following terms:\nYou may create a printed copy of this documentation solely for your own personal use. Conversion to other formats is allowed as long as the actual content is not altered or edited in any way. You shall not publish or distribute this documentation in any form or on any media, except if you distribute the documentation in a manner similar to how Oracle disseminates it (that is, electronically for download on a Web site with the software) or on a CD-ROM or similar medium, provided however that the documentation is disseminated together with the software on the same medium. Any other use, such as any dissemination of printed copies or use of this documentation, in whole or in part, in another publication, requires the prior written consent from an authorized representative of Oracle. Oracle and/or its affiliates reserve any and all rights to this documentation not expressly granted above.\n\n**Documentation Accessibility**\n\nFor information about Oracle's commitment to accessibility, visit the Oracle Accessibility Program website at\nhttps://www.oracle.com/corporate/accessibility/.\n\n**Access to Oracle Support for Accessibility**\n\nOracle customers that have purchased support have access to electronic support through My Oracle Support. For information, visit\nhttps://www.oracle.com/corporate/accessibility/learning-support.html#support-tab.\nChapter 1 Introduction to MySQL Connector/Python\n\nMySQL Connector/Python enables Python programs to access MySQL databases, using an API that is compliant with the Python Database API Specification v2.0 (PEP 249).\n\nFor notes detailing the changes in each release of Connector/Python, see MySQL Connector/Python Release Notes.\n\nMySQL Connector/Python includes support for:\n\n- Almost all features provided by MySQL Server up to and including MySQL Server version 8.0. Connector/Python 8.0 also supports X DevAPI. For documentation of the concepts and the usage of MySQL Connector/Python with X DevAPI, see X DevAPI User Guide.\n- Converting parameter values back and forth between Python and MySQL data types, for example Python `datetime` and MySQL `DATETIME`. You can turn automatic conversion on for convenience, or off for optimal performance.\n- All MySQL extensions to standard SQL syntax.\n- Protocol compression, which enables compressing the data stream between the client and server.\n- Connections using TCP/IP sockets and on Unix using Unix sockets.\n- Secure TCP/IP connections using SSL.\n- Self-contained driver. Connector/Python does not require the MySQL client library or any Python modules outside the standard library.\n\nFor information about which versions of Python can be used with different versions of MySQL Connector/Python, see Chapter 3, Connector/Python Versions.\n\n**Note**\n\nConnector/Python does not support the old MySQL Server authentication methods, which means that MySQL versions prior to 4.1 will not work.\nChapter 2 Guidelines for Python Developers\n\nThe following guidelines cover aspects of developing MySQL applications that might not be immediately obvious to developers coming from a Python background:\n\n- For security, do not hardcode the values needed to connect and log into the database in your main script. Python has the convention of a config.py module, where you can keep such values separate from the rest of your code.\n\n- Python scripts often build up and tear down large data structures in memory, up to the limits of available RAM. Because MySQL often deals with data sets that are many times larger than available memory, techniques that optimize storage space and disk I/O are especially important. For example, in MySQL tables, you typically use numeric IDs rather than string-based dictionary keys, so that the key values are compact and have a predictable length. This is especially important for columns that make up the primary key for an InnoDB table, because those column values are duplicated within each secondary index.\n\n- Any application that accepts input must expect to handle bad data. The bad data might be accidental, such as out-of-range values or misformatted strings. The application can use server-side checks such as unique constraints and NOT NULL constraints, to keep the bad data from ever reaching the database. On the client side, use techniques such as exception handlers to report any problems and take corrective action.\n\nThe bad data might also be deliberate, representing an “SQL injection” attack. For example, input values might contain quote marks, semicolons, % and _ wildcard characters and other characters significant in SQL statements. Validate input values to make sure they have only the expected characters. Escape any special characters that could change the intended behavior when substituted into an SQL statement. Never concatenate a user input value into an SQL statement without doing validation and escaping first. Even when accepting input generated by some other program, expect that the other program could also have been compromised and be sending you incorrect or malicious data.\n\n- Because the result sets from SQL queries can be very large, use the appropriate method to retrieve items from the result set as you loop through them. fetchone() retrieves a single item, when you know the result set contains a single row. fetchall() retrieves all the items, when you know the result set contains a limited number of rows that can fit comfortably into memory. fetchmany() is the general-purpose method when you cannot predict the size of the result set: you keep calling it and looping through the returned items, until there are no more results to process.\n\n- Since Python already has convenient modules such as pickle and cPickle to read and write data structures on disk, data that you choose to store in MySQL instead is likely to have special characteristics:\n\n - Too large to all fit in memory at one time. You use SELECT statements to query only the precise items you need, and aggregate functions to perform calculations across multiple items. You configure the innodb_buffer_pool_size option within the MySQL server to dedicate a certain amount of RAM for caching table and index data.\n\n - Too complex to be represented by a single data structure. You divide the data between different SQL tables. You can recombine data from multiple tables by using a join query. You make sure that related data is kept in sync between different tables by setting up foreign key relationships.\n\n - Updated frequently, perhaps by multiple users simultaneously. The updates might only affect a small portion of the data, making it wasteful to write the whole structure each time. You use the SQL INSERT, UPDATE, and DELETE statements to update different items concurrently, writing only the changed values to disk. You use InnoDB tables and transactions to keep write operations from conflicting with each other, and to return consistent query results even as the underlying data is being updated.\n• Using MySQL best practices for performance can help your application to scale without requiring major rewrites and architectural changes. See Optimization for best practices for MySQL performance. It offers guidelines and tips for SQL tuning, database design, and server configuration.\n\n• You can avoid reinventing the wheel by learning the MySQL SQL statements for common operations: operators to use in queries, techniques for bulk loading data, and so on. Some statements and clauses are extensions to the basic ones defined by the SQL standard. See Data Manipulation Statements, Data Definition Statements, and SELECT Statement for the main classes of statements.\n\n• Issuing SQL statements from Python typically involves declaring very long, possibly multi-line string literals. Because string literals within the SQL statements could be enclosed by single quotation, double quotation marks, or contain either of those characters, for simplicity you can use Python’s triple-quoting mechanism to enclose the entire statement. For example:\n\n```sql\n'''It doesn't matter if this string contains 'single'\nor \"double\" quotes, as long as there aren't 3 in a row.'''\n```\n\nYou can use either of the ' or \" characters for triple-quoting multi-line string literals.\n\n• Many of the secrets to a fast, scalable MySQL application involve using the right syntax at the very start of your setup procedure, in the CREATE TABLE statements. For example, Oracle recommends the `ENGINE=INNODB` clause for most tables, and makes InnoDB the default storage engine in MySQL 5.5 and up. Using InnoDB tables enables transactional behavior that helps scalability of read-write workloads and offers automatic crash recovery. Another recommendation is to declare a numeric primary key for each table, which offers the fastest way to look up values and can act as a pointer to associated values in other tables (a foreign key). Also within the CREATE TABLE statement, using the most compact column data types that meet your application requirements helps performance and scalability because that enables the database server to move less data back and forth between memory and disk.\nChapter 3 Connector/Python Versions\n\nThe following table summarizes the available Connector/Python versions. For series that have reached General Availability (GA) status, development releases in the series prior to the GA version are no longer supported.\n\nNote\nMySQL Connectors and other MySQL client tools and applications now synchronize the first digit of their version number with the (highest) MySQL server version they support. For example, MySQL Connector/Python 8.0.12 would be designed to support all features of MySQL server version 8 (or lower). This change makes it easy and intuitive to decide which client version to use for which server version.\n\nConnector/Python 8.0.4 is the first release to use the new numbering. It is the successor to Connector/Python 2.2.3.\n\nTable 3.1 Connector/Python Version Reference\n\n<table>\n<thead>\n<tr>\n<th>Connector/Python Version</th>\n<th>MySQL Server Versions</th>\n<th>Python Versions</th>\n<th>Connector Status</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>8.0</td>\n<td>8.0, 5.7, 5.6, 5.5</td>\n<td>3.9, 3.8, 3.7, (3.6 before 8.0.29), (2.7 and 3.5 before 8.0.24)</td>\n<td>General Availability</td>\n</tr>\n<tr>\n<td>2.2 (continues as 8.0)</td>\n<td>5.7, 5.6, 5.5</td>\n<td>3.5, 3.4, 2.7</td>\n<td>Developer Milestone, No releases</td>\n</tr>\n<tr>\n<td>2.1</td>\n<td>5.7, 5.6, 5.5</td>\n<td>3.5, 3.4, 2.7, 2.6</td>\n<td>General Availability</td>\n</tr>\n<tr>\n<td>2.0</td>\n<td>5.7, 5.6, 5.5</td>\n<td>3.5, 3.4, 2.7, 2.6</td>\n<td>GA, final release on 2016-10-26</td>\n</tr>\n<tr>\n<td>1.2</td>\n<td>5.7, 5.6, 5.5 (5.1, 5.0, 4.1)</td>\n<td>3.4, 3.3, 3.2, 3.1, 2.7, 2.6</td>\n<td>GA, final release on 2014-08-22</td>\n</tr>\n</tbody>\n</table>\n\nNote\nMySQL server and Python versions within parentheses are known to work with Connector/Python, but are not officially supported. Bugs might not get fixed for those versions.\n\nNote\nConnector/Python does not support the old MySQL Server authentication methods, which means that MySQL versions prior to 4.1 will not work.\n\nNote\nOn macOS x86_64 ARM: Python 3.7 is not supported with the c-ext implementation; note this is a non-default version of Python on macOS.\nChapter 4 Connector/Python Installation\n\nTable of Contents\n\n4.1 Obtaining Connector/Python .......................................................... 8\n4.2 Installing Connector/Python from a Binary Distribution ....................... 8\n4.3 Installing Connector/Python from a Source Distribution ...................... 10\n4.4 Verifying Your Connector/Python Installation ................................ 12\n\nConnector/Python runs on any platform where Python is installed. Python comes preinstalled on most Unix and Unix-like systems, such as Linux, macOS, and FreeBSD. On Microsoft Windows, a Python installer is available at the Python Download website. If necessary, download and install Python for Windows before attempting to install Connector/Python.\n\nNote\nConnector/Python requires python to be in the system's PATH and installation fails if python cannot be located. On Unix and Unix-like systems, python is normally located in a directory included in the default PATH setting. On Windows, if you install Python, either enable Add python.exe to Path during the installation process, or manually add the directory containing python.exe yourself.\n\nFor more information about installation and configuration of Python on Windows, see Using Python on Windows in the Python documentation.\n\nConnector/Python implements the MySQL client/server protocol two ways:\n\n• As pure Python; an implementation written in Python. Its dependencies are the Python Standard Library and Python Protobuf >= 4.21.1,< 4.21.12.\n\nNote\nEL7 and Ubuntu 16.04 do not provide Python Protobuf 3+ making the pure Python version unavailable on those platforms; use the C Extension variant there instead. You may have to --force the installation but may not use use_pure=True.\n\n• As a C Extension that interfaces with the MySQL C client library. This implementation of the protocol is dependent on the client library, but can use the library provided by MySQL Server packages (see MySQL C API Implementations).\n\nNeither implementation of the client/server protocol has any third-party dependencies. However, if you need SSL support, verify that your Python installation has been compiled using the OpenSSL libraries.\n\nTLS Support\n\nBy default, EL8 and Debian 10 supports TLSv1.2 and later when the policy level is set to DEFAULT. To support TLSv1 and TLSv1.1, the policy needs to be changed to LEGACY. This means that a default EL8/DEB10 setup cannot make connections with TLSv1 and TLSv1.1 using the C-extension. Other platforms may change their default behavior in the future.\n\nThe TLSv1.0 and TLSv1.1 connection protocols are deprecated as of Connector/Python 8.0.26 and support for them was removed in Connector/Python 8.0.28.\n\nNote\nSupport for distutils was removed in Connector/Python 8.0.32.\nPython terminology regarding distributions:\n\n- **Built Distribution**: A package created in the native packaging format intended for a given platform. It contains both sources and platform-independent bytecode. Connector/Python binary distributions are built distributions.\n\n- **Source Distribution**: A distribution that contains only source files and is generally platform independent.\n\n### 4.1 Obtaining Connector/Python\n\nPackages are available at the Connector/Python download site. For some packaging formats, there are different packages for different versions of Python; choose the one appropriate for the version of Python installed on your system.\n\n### 4.2 Installing Connector/Python from a Binary Distribution\n\nConnector/Python installers in native package formats are available for Windows and for Unix and Unix-like systems:\n\n- **Windows**: MSI installer package\n- **Linux**: Yum repository for EL7 and EL8 and Fedora; RPM packages for Oracle Linux, Red Hat, and SuSE; Debian packages for Debian and Ubuntu\n- **macOS**: Disk image package with PKG installer\n\nYou may need root or administrator privileges to perform the installation operation.\n\n**Note**\n\nPrior to Connector/Python 8.0.22, the C extension and pure Python implementations were installed using two separate binary distributions; except they were always combined for Windows and macOS. The C extension implementation had “cext” in the package name.\n\nBinary distributions that provide the C Extension link to an already installed C client library provided by a MySQL Server installation. For those distributions that are not statically linked, you must install MySQL Server if it is not already present on your system. To obtain it, visit the MySQL download site.\n\n### Installing Connector/Python with pip\n\nUse `pip` to install Connector/Python on most any operating system:\n\n```\n$> pip install mysql-connector-python\n```\n\n### Installing Connector/Python on Microsoft Windows\n\nManaging all of your MySQL products, including MySQL Connector/Python, with MySQL Installer is the recommended approach. It handles all requirements and prerequisites, configurations, and upgrades.\n\n**Prerequisite.** The **Microsoft Visual C++ 2015 Redistributable** must be installed on your system.\n\n- **MySQL Installer (recommended)**: When executing MySQL Installer, choose MySQL Connector/Python as one of the products to install. MySQL Installer installer the Windows MSI Installer described in this documentation.\n\n- **Windows MSI Installer** (*.msi* file): To use the MSI Installer, launch it and follow the prompts in the screens it presents to install Connector/Python in the location of your choosing.\nLike with MySQL Installer, subsequent executions of the Connector/Python MSI enable you to either repair or remove the existing Connector/Python installation.\n\nConnector/Python Windows MSI Installers (.msi files) are available from the Connector/Python download site (see Section 4.1, “Obtaining Connector/Python”). Choose an installer appropriate for the version of Python installed on your system. As of Connector/Python 2.1.1, MSI Installers include the C Extension; it need not be installed separately.\n\nAlternatively, to run the installer from the command line, use this command in a console window, where \\texttt{VER} and \\texttt{PYVER} are the respective Connector/Python and Python version numbers in the installer file name:\n\n\\begin{verbatim}\n$> msiexec /i mysql-connector-python-VER-pyPYVER.msi\n\\end{verbatim}\n\nSubsequent executions of Connector/Python using the MSI installer permit you to either repair or remove the existing Connector/Python installation.\n\n\\section*{Installing Connector/Python on Linux Using the MySQL Yum Repository}\n\nFor EL7 or EL8-based platforms and Fedora, you can install Connector/Python using the MySQL Yum repository (see Installing Additional MySQL Products and Components with Yum). You must have the MySQL Yum repository on your system's repository list (for details, see Adding the MySQL Yum Repository). To make sure that your Yum repository is up-to-date, use this command:\n\n\\begin{verbatim}\n$> sudo yum update mysql-community-release\n\\end{verbatim}\n\n\\subsection*{Prerequisites}\n\n\\begin{itemize}\n \\item On EL7, EL8, and SUSE: A \\texttt{python3-protobuf} RPM package is not available for Python 3.8 on these platforms, so the dependency is not part of the RPM specification; instead it must be manually installed with the likes of \\texttt{pip install protobuf}. This is required as of v8.0.29.\n \\item Although optional, the \\texttt{mysql-community-client-plugins} package is required to use newer authentication methods, such as \\texttt{caching_sha2_password} that's the default authentication method as of MySQL 8.0.\n\\end{itemize}\n\n\\begin{verbatim}\n$> sudo yum install mysql-community-client-plugins\n\\end{verbatim}\n\nThen install Connector/Python as follows:\n\n\\begin{verbatim}\n$> sudo yum install mysql-connector-python\n\\end{verbatim}\n\n\\section*{Installing Connector/Python on Linux Using an RPM Package}\n\nConnector/Python Linux RPM packages (.rpm files) are available from the Connector/Python download site (see Section 4.1, “Obtaining Connector/Python”).\n\nTo install a Connector/Python RPM package (denoted here as \\texttt{PACKAGE.rpm}), use this command:\n\n\\begin{verbatim}\n$> rpm -i PACKAGE.rpm\n\\end{verbatim}\n\n\\subsection*{Prerequisites}\n\n\\begin{itemize}\n \\item On EL7, EL8, and SUSE: A \\texttt{python3-protobuf} RPM package is not available for Python 3.8 on these platforms, so the dependency is not part of the RPM specification; instead it must be manually installed with the likes of \\texttt{pip install protobuf}. This is required as of v8.0.29.\n \\item Although optional, the \\texttt{mysql-community-client-plugins} package is required to use newer authentication methods, such as \\texttt{caching_sha2_password} that's the default authentication method as of MySQL 8.0.\n\\end{itemize}\nInstalling Connector/Python on Linux Using a Debian Package\n\nConnector/Python Debian packages (.deb files) are available for Debian or Debian-like Linux systems from the Connector/Python download site (see Section 4.1, “Obtaining Connector/Python”).\n\n**Prerequisite.** Although optional, the mysql-community-client-plugins package is required to use newer authentication methods, such as caching_sha2_password that’s the default authentication method as of MySQL 8.0.\n\nTo install a Connector/Python Debian package (denoted here as PACKAGE.deb), use this command:\n\n```bash\n$> dpkg -i PACKAGE.deb\n```\n\n**Note**\nPrior to Connector/Python 8.0.22, the C extension implementation was a separate DEB package that contained “cext” in the name.\n\nInstalling Connector/Python on macOS Using a Disk Image\n\nConnector/Python macOS disk images (.dmg files) are available from the Connector/Python download site (see Section 4.1, “Obtaining Connector/Python”). As of Connector/Python 2.1.1, macOS disk images include the C Extension; it need not be installed separately.\n\nDownload the .dmg file and install Connector/Python by opening it and double clicking the resulting .pkg file.\n\n4.3 Installing Connector/Python from a Source Distribution\n\nConnector/Python source distributions are platform independent and can be used on any platform. Source distributions are packaged in two formats:\n\n- Zip archive format (.zip file)\n- Compressed tar archive format (.tar.gz file)\n\nEither packaging format can be used on any platform, but Zip archives are more commonly used on Windows systems and tar archives on Unix and Unix-like systems.\n\nPrerequisites for Compiling Connector/Python with the C Extension\n\nAs of Connector/Python 2.1.1, source distributions include the C Extension that interfaces with the MySQL C client library. You can build the distribution with or without support for this extension. To build Connector/Python with support for the C Extension, you must satisfy the following prerequisites.\n\n**Note**\nPython 2.7 support was removed in Connector/Python 8.0.24, and Python 3.7 support was removed in Connector/Python 8.1.0.\n\n- Linux: A C/C++ compiler, such as gcc\n- Windows: Current version of Visual Studio\nInstalling Connector/Python from Source on Microsoft Windows\n\n- Protobuf C++ (version >= 4.21.1,<=4.21.12) for the C extension and/or Python's protobuf package for the pure Python implementation\n- Python development files\n- MySQL Server installed, including development files to compile the optional C Extension that interfaces with the MySQL C client library\n\nYou must install MySQL Server if it is not already present on your system. To obtain it, visit the MySQL download site.\n\nFor certain platforms, MySQL development files are provided in separate packages. This is true for RPM and Debian packages, for example.\n\nInstalling Connector/Python from Source on Microsoft Windows\n\nA Connector/Python Zip archive (.zip file) is available from the Connector/Python download site (see Section 4.1, “Obtaining Connector/Python”).\n\nTo install Connector/Python from a Zip archive, download the latest version and follow these steps:\n\n1. Unpack the Zip archive in the intended installation directory (for example, C:\\mysql-connector\\) using WinZip or another tool that can read .zip files.\n\n2. Start a console window and change location to the folder where you unpacked the Zip archive:\n\n ```shell\n $> cd C:\\mysql-connector\\n ```\n\n3. Inside the Connector/Python folder, perform the installation using this command:\n\n ```shell\n $> python setup.py install\n ```\n\n To include the C Extension (available as of Connector/Python 2.1.1), use this command instead:\n\n ```shell\n $> python setup.py install --with-mysql-capi=\"path_name\"\n ```\n\n The argument to `--with-mysql-capi` is the path to the installation directory of MySQL Server.\n\nTo see all options and commands supported by `setup.py`, use this command:\n\n```shell\n$> python setup.py --help\n```\nVerifying Your Connector/Python Installation\n\nThe argument to --with-mysql-capi is the path to the installation directory of MySQL Server, or the path to the mysql_config command.\n\nTo see all options and commands supported by setup.py, use this command:\n\n```bash\n$ python setup.py --help\n```\n\n### 4.4 Verifying Your Connector/Python Installation\n\nOn Windows, the default Connector/Python installation location is `C:\\PythonX.Y\\Lib\\site-packages`, where `X.Y` is the Python version you used to install the connector.\n\nOn Unix-like systems, the default Connector/Python installation location is `/prefix/pythonX.Y/site-packages/`, where `prefix` is the location where Python is installed and `X.Y` is the Python version. See How installation works in the Python manual.\n\nThe C Extension is installed as `_mysql_connector.so` in the `site-packages` directory, not in the `mysql/connector` directory.\n\nDepending on your platform, the installation path might differ from the default. If you are not sure where Connector/Python is installed, do the following to determine its location. The output here shows installation locations as might be seen on macOS:\n\n```bash\n$ python\n>>> from distutils.sysconfig import get_python_lib\n\n>>> print(get_python_lib()) # Python v2.x\n/Library/Python/2.7/site-packages\n\n>>> print(get_python_lib()) # Python v3.x\n/Library/Frameworks/Python.framework/Versions/3.1/lib/python3.1/site-packages\n```\n\nTo test that your Connector/Python installation is working and able to connect to MySQL Server, you can run a very simple program where you supply the login credentials and host information required for the connection. For an example, see Section 5.1, “Connecting to MySQL Using Connector/Python”.\n\n---\n\n--with-protobuf-lib-dir=/dir/to/protobuf/lib\n--with-protoc=/path/to/protoc/binary\n--with-mysql-capi=\"path_name\"\nChapter 5 Connector/Python Coding Examples\n\nTable of Contents\n\n5.1 Connecting to MySQL Using Connector/Python .......................................................... 13\n5.2 Creating Tables Using Connector/Python .................................................................... 14\n5.3 Inserting Data Using Connector/Python ..................................................................... 17\n5.4 Querying Data Using Connector/Python ..................................................................... 18\n\nThese coding examples illustrate how to develop Python applications and scripts which connect to MySQL Server using MySQL Connector/Python.\n\n5.1 Connecting to MySQL Using Connector/Python\n\nThe `connect()` constructor creates a connection to the MySQL server and returns a `MySQLConnection` object.\n\nThe following example shows how to connect to the MySQL server:\n\n```python\nimport mysql.connector\n\ncnx = mysql.connector.connect(user='scott', password='password',\n host='127.0.0.1',\n database='employees')\n\ncnx.close()\n```\n\nSection 7.1, “Connector/Python Connection Arguments” describes the permitted connection arguments.\n\nIt is also possible to create connection objects using the `connection.MySQLConnection()` class:\n\n```python\nfrom mysql.connector import connection\n\ncnx = connection.MySQLConnection(user='scott', password='password',\n host='127.0.0.1',\n database='employees')\n\ncnx.close()\n```\n\nBoth forms (either using the `connect()` constructor or the class directly) are valid and functionally equal, but using `connect()` is preferred and used by most examples in this manual.\n\nTo handle connection errors, use the `try` statement and catch all errors using the `errors.Error` exception:\n\n```python\nimport mysql.connector\nfrom mysql.connector import errorcode\n\ntry:\n cnx = mysql.connector.connect(user='scott',\n database='employ')\nexcept mysql.connector.Error as err:\n if err.errno == errorcode.ER_ACCESS_DENIED_ERROR:\n print(\"Something is wrong with your user name or password\")\n elif err.errno == errorcode.ER_BAD_DB_ERROR:\n print(\"Database does not exist\")\n else:\n print(err)\nelse:\n cnx.close()\n```\n\nDefining connection arguments in a dictionary and using the `**` operator is another option:\n\n```python\nimport mysql.connector\n\nconfig = {\n 'user': 'scott',\n```\nUsing the Connector/Python Python or C Extension\n\nConnector/Python offers two implementations: a pure Python interface and a C extension that uses the MySQL C client library (see Chapter 8, The Connector/Python C Extension). This can be configured at runtime using the `use_pure` connection argument. It defaults to `False` as of MySQL 8, meaning the C extension is used. If the C extension is not available on the system then `use_pure` defaults to `True`. Setting `use_pure=False` causes the connection to use the C Extension if your Connector/Python installation includes it, while `use_pure=True` to `False` means the Python implementation is used if available.\n\nNote\n\nThe `use_pure` option and C extension were added in Connector/Python 2.1.1.\n\nThe following example shows how to set `use_pure` to False.\n\n```python\nimport mysql.connector\n\ncnx = mysql.connector.connect(user='scott', password='password',\n host='127.0.0.1',\n database='employees',\n use_pure=False)\n\ncnx.close()\n```\n\nIt is also possible to use the C Extension directly by importing the `_mysql_connector` module rather than the `mysql.connector` module. For more information, see Section 8.2, \"The _mysql_connector C Extension Module\".\n\n5.2 Creating Tables Using Connector/Python\n\nAll DDL (Data Definition Language) statements are executed using a handle structure known as a cursor. The following examples show how to create the tables of the Employee Sample Database. You need them for the other examples.\n\nIn a MySQL server, tables are very long-lived objects, and are often accessed by multiple applications written in different languages. You might typically work with tables that are already set up, rather than creating them within your own application. Avoid setting up and dropping tables over and over again, as that is an expensive operation. The exception is temporary tables, which can be created and dropped quickly within an application.\n\n```python\nfrom __future__ import print_function\nimport mysql.connector\nfrom mysql.connector import errorcode\n\nDB_NAME = 'employees'\nTABLES = {}\n\nTABLES['employees'] = ('\n `emp_no` int(11) NOT NULL AUTO_INCREMENT,\n `birth_date` date NOT NULL,\n `first_name` varchar(14) NOT NULL,\n `last_name` varchar(16) NOT NULL,\n `gender` enum('M','F') NOT NULL,\n `hire_date` date NOT NULL,\n')\n```\nThe preceding code shows how we are storing the CREATE statements in a Python dictionary called TABLES. We also define the database in a global variable called DB_NAME, which enables you to easily use a different schema.\n\ncnx = mysql.connector.connect(user='scott')\ncursor = cnx.cursor()\n\nA single MySQL server can manage multiple databases. Typically, you specify the database to switch to when connecting to the MySQL server. This example does not connect to the database upon connection, so that it can make sure the database exists, and create it if not:\n```python\ndef create_database(cursor):\n try:\n cursor.execute(\"CREATE DATABASE {} DEFAULT CHARACTER SET 'utf8'\".format(DB_NAME))\n except mysql.connector.Error as err:\n print(\"Failed creating database: {}\".format(err))\n exit(1)\n try:\n cursor.execute(\"USE {}\".format(DB_NAME))\n except mysql.connector.Error as err:\n print(\"Database {} does not exist.\".format(DB_NAME))\n if err.errno == errorcode.ER_BAD_DB_ERROR:\n create_database(cursor)\n print(\"Database {} created successfully.\".format(DB_NAME))\n cnx.database = DB_NAME\n else:\n print(err)\n exit(1)\n except mysql.connector.Error as err:\n print(\"Error in Use Database: {}\".format(err))\n exit(1)\n\nfor table_name in TABLES:\n table_description = TABLES[table_name]\n try:\n print(\"Creating table {}: \"\".format(table_name), end=''\n cursor.execute(table_description)\n except mysql.connector.Error as err:\n if err.errno == errorcode.ER_TABLE_EXISTS_ERROR:\n print(\"already exists.\")\n else:\n print(err.msg)\n else:\n print(\"OK\")\n\ncursor.close()\ncnx.close()\n```\n\nWe first try to change to a particular database using the `database` property of the connection object `cnx`. If there is an error, we examine the error number to check if the database does not exist. If so, we call the `create_database` function to create it for us.\n\nOn any other error, the application exits and displays the error message.\n\nAfter we successfully create or change to the target database, we create the tables by iterating over the items of the `TABLES` dictionary:\n\n```python\nfor table_name in TABLES:\n table_description = TABLES[table_name]\n try:\n print(\"Creating table {}: \", end='')\n cursor.execute(table_description)\n except mysql.connector.Error as err:\n if err.errno == errorcode.ER_TABLE_EXISTS_ERROR:\n print(\"already exists.\")\n else:\n print(err.msg)\n else:\n print(\"OK\")\ncursor.close()\ncnx.close()\n```\n\nTo handle the error when the table already exists, we notify the user that it was already there. Other errors are printed, but we continue creating tables. (The example shows how to handle the “table already exists” condition for illustration purposes. In a real application, we would typically avoid the error condition entirely by using the `IF NOT EXISTS` clause of the `CREATE TABLE` statement.)\n\nThe output would be something like this:\n\n```\nDatabase employees does not exists.\nDatabase employees created successfully.\nCreating table employees: OK\nCreating table departments: already exists.\nCreating table salaries: already exists.\nCreating table dept_emp: OK\nCreating table dept_manager: OK\nCreating table titles: OK\n```\n\nTo populate the employees tables, use the dump files of the Employee Sample Database. Note that you only need the data dump files that you will find in an archive named like `employees_db-dump-files-1.0.5.tar.bz2`. After downloading the dump files, execute the following commands, adding connection options to the `mysql` commands if necessary:\n\n```\n$> tar xzf employees_db-dump-files-1.0.5.tar.bz2\n$> cd employees_db\n```\n5.3 Inserting Data Using Connector/Python\n\nInserting or updating data is also done using the handler structure known as a cursor. When you use a transactional storage engine such as InnoDB (the default in MySQL 5.5 and higher), you must commit the data after a sequence of INSERT, DELETE, and UPDATE statements.\n\nThis example shows how to insert new data. The second INSERT depends on the value of the newly created primary key of the first. The example also demonstrates how to use extended formats. The task is to add a new employee starting to work tomorrow with a salary set to 50000.\n\nNote\nThe following example uses tables created in the example Section 5.2, \"Creating Tables Using Connector/Python\". The AUTO_INCREMENT column option for the primary key of the employees table is important to ensure reliable, easily searchable data.\n\nfrom __future__ import print_function\nfrom datetime import date, datetime, timedelta\nimport mysql.connector\n\ncnx = mysql.connector.connect(user='scott', database='employees')\ncursor = cnx.cursor()\ntomorrow = datetime.now().date() + timedelta(days=1)\n\nadd_employee = ('%INSERT INTO employees \n \"(first_name, last_name, hire_date, gender, birth_date) \"\n \"VALUES (%s, %s, %s, %s)\"\nadd_salary = ('%INSERT INTO salaries \n \"(emp_no, salary, from_date, to_date) \"\n \"VALUES (%(emp_no)s, %(salary)s, %(from_date)s, %(to_date)s)\"\ndata_employee = ('Geert', 'Vanderkelen', tomorrow, 'M', date(1977, 6, 14))\n\n# Insert new employee\ncursor.execute(add_employee, data_employee)\nemp_no = cursor.lastrowid\n\n# Insert salary information\ndata_salary = { 'emp_no': emp_no,\n 'salary': 50000,\n 'from_date': tomorrow,\n 'to_date': date(9999, 1, 1),\n}\ncursor.execute(add_salary, data_salary)\n\ncnx.commit()\ncnx.close()\n\nWe first open a connection to the MySQL server and store the connection object in the variable cnx. We then create a new cursor, by default a MySQLCursor object, using the connection's cursor() method.\n\nWe could calculate tomorrow by calling a database function, but for clarity we do it in Python using the datetime module.\nBoth **INSERT** statements are stored in the variables called `add_employee` and `add_salary`. Note that the second **INSERT** statement uses extended Python format codes.\n\nThe information of the new employee is stored in the tuple `data_employee`. The query to insert the new employee is executed and we retrieve the newly inserted value for the `emp_no` column (an **AUTO_INCREMENT** column) using the `lastrowid` property of the cursor object.\n\nNext, we insert the new salary for the new employee, using the `emp_no` variable in the dictionary holding the data. This dictionary is passed to the `execute()` method of the cursor object if an error occurred.\n\nSince by default Connector/Python turns **autocommit** off, and MySQL 5.5 and higher uses transactional **InnoDB** tables by default, it is necessary to commit your changes using the connection’s `commit()` method. You could also **roll back** using the `rollback()` method.\n\n### 5.4 Querying Data Using Connector/Python\n\nThe following example shows how to query data using a cursor created using the connection’s `cursor()` method. The data returned is formatted and printed on the console.\n\nThe task is to select all employees hired in the year 1999 and print their names and hire dates to the console.\n\n```python\nimport datetime\nimport mysql.connector\n\ncnx = mysql.connector.connect(user='scott', database='employees')\ncursor = cnx.cursor()\n\nquery = (\"SELECT first_name, last_name, hire_date FROM employees \n \"WHERE hire_date BETWEEN %s AND %s\")\nhire_start = datetime.date(1999, 1, 1)\nhire_end = datetime.date(1999, 12, 31)\ncursor.execute(query, (hire_start, hire_end))\n\nfor (first_name, last_name, hire_date) in cursor:\n print(\"{} {}, {} was hired on {:%d %b %Y}\").format(\n last_name, first_name, hire_date))\ncursor.close()\ncnx.close()```\n\nWe first open a connection to the MySQL server and store the **connection object** in the variable `cnx`. We then create a new cursor, by default a **MySQLCursor** object, using the connection’s `cursor()` method.\n\nIn the preceding example, we store the **SELECT** statement in the variable `query`. Note that we are using unquoted `%s`-markers where dates should have been. Connector/Python converts `hire_start` and `hire_end` from Python types to a data type that MySQL understands and adds the required quotes. In this case, it replaces the first `%s` with '1999-01-01', and the second with '1999-12-31'.\n\nWe then execute the operation stored in the `query` variable using the `execute()` method. The data used to replace the `%s`-markers in the query is passed as a tuple: `(hire_start, hire_end)`.\n\nAfter executing the query, the MySQL server is ready to send the data. The result set could be zero rows, one row, or 100 million rows. Depending on the expected volume, you can use different techniques to process this result set. In this example, we use the `cursor` object as an iterator. The first column in the row is stored in the variable `first_name`, the second in `last_name`, and the third in `hire_date`.\n\nWe print the result, formatting the output using Python’s built-in `format()` function. Note that `hire_date` was converted automatically by Connector/Python to a Python `datetime.date` object. This means that we can easily format the date in a more human-readable form.\nThe output should be something like this:\n\n.. \nWilharm, LiMin was hired on 16 Dec 1999 \nWielonsky, Lalit was hired on 16 Dec 1999 \nKamble, Dannz was hired on 18 Dec 1999 \nDuBourdieux, Zhongwei was hired on 19 Dec 1999 \nFujisawa, Rosita was hired on 20 Dec 1999 \n..\n6.1 Tutorial: Raise Employee's Salary Using a Buffered Cursor\n\nThe following example script gives a long-overdue 15% raise effective tomorrow to all employees who joined in the year 2000 and are still with the company.\n\nTo iterate through the selected employees, we use buffered cursors. (A buffered cursor fetches and buffers the rows of a result set after executing a query; see Section 10.6.1, “cursor.MySQLCursorBuffered Class.”) This way, it is unnecessary to fetch the rows in a new variables. Instead, the cursor can be used as an iterator.\n\n```\nfrom __future__ import print_function\nfrom decimal import Decimal\nfrom datetime import datetime, date, timedelta\nimport mysql.connector\n\n# Connect with the MySQL Server\ncnx = mysql.connector.connect(user='scott', database='employees')\n\ncurA = cnx.cursor(buffered=True)\ncurB = cnx.cursor(buffered=True)\n\n# Query to get employees who joined in a period defined by two dates\nquery = (\"SELECT s.emp_no, salary, from_date, to_date FROM employees AS e \n LEFT JOIN salaries AS s USING (emp_no) \n WHERE to_date = DATE('9999-01-01') \n AND e.hire_date BETWEEN DATE(%s) AND DATE(%s)\")\n\n# UPDATE and INSERT statements for the old and new salary\nupdate_old_salary = (\"UPDATE salaries SET to_date = %s \n WHERE emp_no = %s AND from_date = %s\")\ninsert_new_salary = (\"INSERT INTO salaries (emp_no, from_date, to_date, salary) \n VALUES (%s, %s, %s, %s\")\n\n# Select the employees getting a raise\ncurA.execute(query, (date(2000, 1, 1), date(2000, 12, 31)))\n\n# Iterate through the result of curA\nfor (emp_no, salary, from_date, to_date) in curA:\n # Update the old and insert the new salary\n new_salary = int(round(salary * Decimal('1.15')))\n curB.execute(update_old_salary, (tomorrow, emp_no, from_date))\n curB.execute(insert_new_salary,\n (emp_no, tomorrow, date(9999, 1, 1), new_salary))\n\n# Commit the changes\n```\ncnx.commit()\ncnx.close()\nChapter 7 Connector/Python Connection Establishment\n\nTable of Contents\n\n7.1 Connector/Python Connection Arguments ................................................................. 23\n7.2 Connector/Python Option-File Support ........................................................................... 30\n\nConnector/Python provides a `connect()` call used to establish connections to the MySQL server. The following sections describe the permitted arguments for `connect()` and describe how to use option files that supply additional arguments.\n\n7.1 Connector/Python Connection Arguments\n\nA connection with the MySQL server can be established using either the `mysql.connector.connect()` function or the `mysql.connector.MySQLConnection()` class:\n\n```python\nimport mysql.connector as mc\n\n# Using function\ncnx = mc.connect(user='joe', database='test')\n\n# Using class\ncnx = mc.MySQLConnection(user='joe', database='test')\n```\n\nThe following table describes the arguments that can be used to initiate a connection. An asterisk (*) following an argument indicates a synonymous argument name, available only for compatibility with other Python MySQL drivers. Oracle recommends not to use these alternative names.\n\n<table>\n<thead>\n<tr>\n<th>Argument Name</th>\n<th>Default</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>user</td>\n<td></td>\n<td>The user name used to authenticate with the MySQL server.</td>\n</tr>\n<tr>\n<td>password</td>\n<td></td>\n<td>The password to authenticate the user with the MySQL server.</td>\n</tr>\n<tr>\n<td>password1, password2, and password3</td>\n<td></td>\n<td>For Multi-Factor Authentication (MFA); <code>password1</code> is an alias for <code>password</code>. Added in 8.0.28.</td>\n</tr>\n<tr>\n<td>database</td>\n<td></td>\n<td>The database name to use when connecting with the MySQL server.</td>\n</tr>\n<tr>\n<td>host</td>\n<td>127.0.0.1</td>\n<td>The host name or IP address of the MySQL server.</td>\n</tr>\n<tr>\n<td>unix_socket</td>\n<td></td>\n<td>The location of the Unix socket file.</td>\n</tr>\n<tr>\n<td>port</td>\n<td>3306</td>\n<td>The TCP/IP port of the MySQL server. Must be an integer.</td>\n</tr>\n<tr>\n<td>conn_attrs</td>\n<td></td>\n<td>Standard <code>performance_schema.session_connect_attrs</code> values are sent; use <code>conn_attrs</code> to optionally set additional custom connection attributes as defined by a dictionary such as <code>config['conn_attrs'] = {"foo": "bar"}.</code> The c-ext and pure python implementations differ. The c-ext implementation depends on the mysqlclient library so its standard conn_attrs values originate from it. For example, <code>'_client_name'</code> is 'libmysql' with c-ext but 'mysql-connector-python' with pure python. C-ext adds these additional attributes: <code>'_connector_version', '_connector_license', '_connector_name', and '_source_host'</code>. This option was added in 8.0.17, as was the default <code>session_connect_attrs</code> behavior.</td>\n</tr>\n</tbody>\n</table>\n\n---\n\n23\n## Connector/Python Connection Arguments\n\n<table>\n<thead>\n<tr>\n<th>Argument Name</th>\n<th>Default</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>init_command</code></td>\n<td></td>\n<td>Command (SQL query) executed immediately after the connection is established as part of the initialization process. Added in 8.0.32.</td>\n</tr>\n<tr>\n<td><code>auth_plugin</code></td>\n<td></td>\n<td>Authentication plugin to use. Added in 1.2.1.</td>\n</tr>\n<tr>\n<td><code>fido_callback</code></td>\n<td></td>\n<td>An callable defined by the optional <code>fido_callback</code> option is executed when it's ready for user interaction with the hardware FIDO device. This option can be a callable object or a string path that the connector can import in runtime and execute. It does not block and is only used to notify the user of the need for interaction with the hardware FIDO device. This functionality is only available in the C extension. A <code>NotSupportedError</code> is raised when using the pure Python implementation.</td>\n</tr>\n<tr>\n<td><code>use_unicode</code></td>\n<td><code>True</code></td>\n<td>Whether to use Unicode.</td>\n</tr>\n<tr>\n<td><code>charset</code></td>\n<td><code>utf8mb4</code></td>\n<td>Which MySQL character set to use.</td>\n</tr>\n<tr>\n<td><code>collation</code></td>\n<td><code>utf8mb4_general_ci</code></td>\n<td>Which MySQL collation to use. The 8.x default values are generated from the latest MySQL Server 8.0 defaults.</td>\n</tr>\n<tr>\n<td><code>autocommit</code></td>\n<td><code>False</code></td>\n<td>Whether to autocommit transactions.</td>\n</tr>\n<tr>\n<td><code>time_zone</code></td>\n<td></td>\n<td>Set the <code>time_zone</code> session variable at connection time.</td>\n</tr>\n<tr>\n<td><code>sql_mode</code></td>\n<td></td>\n<td>Set the <code>sql_mode</code> session variable at connection time.</td>\n</tr>\n<tr>\n<td><code>get_warnings</code></td>\n<td><code>False</code></td>\n<td>Whether to fetch warnings.</td>\n</tr>\n<tr>\n<td><code>raise_on_warnings</code></td>\n<td><code>False</code></td>\n<td>Whether to raise an exception on warnings.</td>\n</tr>\n<tr>\n<td><code>connection_timeout</code></td>\n<td></td>\n<td>Timeout for the TCP and Unix socket connections.</td>\n</tr>\n<tr>\n<td><code>client_flags</code></td>\n<td></td>\n<td>MySQL client flags.</td>\n</tr>\n<tr>\n<td><code>buffered</code></td>\n<td><code>False</code></td>\n<td>Whether cursor objects fetch the results immediately after executing queries.</td>\n</tr>\n<tr>\n<td><code>raw</code></td>\n<td><code>False</code></td>\n<td>Whether MySQL results are returned as is, rather than converted to Python types.</td>\n</tr>\n<tr>\n<td><code>consume_results</code></td>\n<td><code>False</code></td>\n<td>Whether to automatically read result sets.</td>\n</tr>\n<tr>\n<td><code>tls_versions</code></td>\n<td><code>"TLSv1.2", "TLSv1.3"</code></td>\n<td>TLS versions to support; allowed versions are TLSv1.2 and TLSv1.3. Versions TLSv1 and TLSv1.1 were removed in Connector/Python 8.0.28.</td>\n</tr>\n<tr>\n<td><code>ssl_ca</code></td>\n<td></td>\n<td>File containing the SSL certificate authority.</td>\n</tr>\n<tr>\n<td><code>ssl_cert</code></td>\n<td></td>\n<td>File containing the SSL certificate file.</td>\n</tr>\n<tr>\n<td><code>ssl_disabled</code></td>\n<td><code>False</code></td>\n<td>True disables SSL/TLS usage. The TLSv1 and TLSv1.1 connection protocols are deprecated as of Connector/Python 8.0.26 and removed as of Connector/Python 8.0.28.</td>\n</tr>\n<tr>\n<td><code>ssl_key</code></td>\n<td></td>\n<td>File containing the SSL key.</td>\n</tr>\n<tr>\n<td><code>ssl_verify_cert</code></td>\n<td><code>False</code></td>\n<td>When set to <code>True</code>, checks the server certificate against the certificate file specified by the <code>ssl_ca</code> option. Any mismatch causes a <code>ValueError</code> exception.</td>\n</tr>\n<tr>\n<td>Argument Name</td>\n<td>Default</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------------------------</td>\n<td>---------</td>\n<td>-------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td><code>ssl_verify_identity</code></td>\n<td>False</td>\n<td>When set to <code>True</code>, additionally perform host name identity verification by checking the host name that the client uses for connecting to the server against the identity in the certificate that the server sends to the client. Option added in Connector/Python 8.0.14.</td>\n</tr>\n<tr>\n<td><code>force_ipv6</code></td>\n<td>False</td>\n<td>When set to <code>True</code>, uses IPv6 when an address resolves to both IPv4 and IPv6. By default, IPv4 is used in such cases.</td>\n</tr>\n<tr>\n<td><code>kerberos_auth_mode</code></td>\n<td>SSPI</td>\n<td>Windows-only, for choosing between SSPI and GSSAPI at runtime for the <code>authentication_kerberos_client</code> authentication plugin on Windows. Option added in Connector/Python 8.0.32.</td>\n</tr>\n<tr>\n<td><code>oci_config_file</code></td>\n<td>""</td>\n<td>Optionally define a specific path to the <code>authentication_oci</code> server-side authentication configuration file. The profile name can be configured with <code>oci_config_profile</code>. The default file path on Linux and macOS is <code>~/.oci/config</code>, and <code>%HOMEDRIVE%\\%HOMEPATH%\\oci\\config</code> on Windows.</td>\n</tr>\n<tr>\n<td><code>oci_config_profile</code></td>\n<td>"DEFAULT"</td>\n<td>Used to specify a profile to use from the OCI configuration file that contains the generated ephemeral key pair and security token. The OCI configuration file location can be defined by <code>oci_config_file</code>. Option <code>oci_config_profile</code> was added in Connector/Python 8.0.33.</td>\n</tr>\n<tr>\n<td><code>dsn</code></td>\n<td>Not supported (raises <code>NotSupportedError</code> when used).</td>\n<td></td>\n</tr>\n<tr>\n<td><code>pool_name</code></td>\n<td></td>\n<td>Connection pool name. The pool name is restricted to alphanumeric characters and the special characters <code>., _*, $, and #</code>. The pool name must be no more than <code>pooling.CNX_POOL_MAXNAMESIZE</code> characters long (default 64).</td>\n</tr>\n<tr>\n<td><code>pool_size</code></td>\n<td>5</td>\n<td>Connection pool size. The pool size must be greater than 0 and less than or equal to <code>pooling.CNX_POOL_MAXSIZE</code> (default 32).</td>\n</tr>\n<tr>\n<td><code>pool_reset_session</code></td>\n<td>True</td>\n<td>Whether to reset session variables when connection is returned to pool.</td>\n</tr>\n<tr>\n<td><code>compress</code></td>\n<td>False</td>\n<td>Whether to use compressed client/server protocol.</td>\n</tr>\n<tr>\n<td><code>converter_class</code></td>\n<td></td>\n<td>Converter class to use.</td>\n</tr>\n<tr>\n<td><code>converter_str_fallback</code></td>\n<td>False</td>\n<td>Enable the conversion to str of value types not supported by the Connector/Python converter class or by a custom converter class.</td>\n</tr>\n<tr>\n<td><code>failover</code></td>\n<td></td>\n<td>Server failover sequence.</td>\n</tr>\n<tr>\n<td><code>option_files</code></td>\n<td></td>\n<td>Which option files to read. Added in 2.0.0.</td>\n</tr>\n<tr>\n<td><code>option_groups</code></td>\n<td>['client', 'connector_python']</td>\n<td>Which groups to read from option files. Added in 2.0.0.</td>\n</tr>\n<tr>\n<td><code>allow_local_infile</code></td>\n<td>True</td>\n<td>Whether to enable <code>LOAD DATA LOCAL INFILE</code>. Added in 2.0.0.</td>\n</tr>\n<tr>\n<td>Argument Name</td>\n<td>Default</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-----------------------</td>\n<td>--------------------------</td>\n<td>---------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>use_pure</td>\n<td>False as of 8.0.11, and True in earlier versions. If only one implementation (C or Python) is available, then the default value is set to enable the available implementation.</td>\n<td>Whether to use pure Python or C Extension. If use_pure=False and the C Extension is not available, then Connector/Python will automatically fall back to the pure Python implementation. Can be set with mysql.connector.connect() but not MySQLConnection.connect(). Added in 2.1.1.</td>\n</tr>\n<tr>\n<td>krb_service_principal</td>\n<td>The "@realm" defaults to the default realm, as configured in the krb5.conf file.</td>\n<td>Must be a string in the form "primary/instance@realm" such as "ldap/idapauth@MYSQL.COM" where "@realm" is optional. Added in 8.0.23.</td>\n</tr>\n</tbody>\n</table>\n\n**MySQL Authentication Options**\n\nAuthentication with MySQL typically uses a **username** and **password**.\n\nWhen the `database` argument is given, the current database is set to the given value. To change the current database later, execute a `USE SQL` statement or set the `database` property of the `MySQLConnection` instance.\n\nBy default, Connector/Python tries to connect to a MySQL server running on the local host using TCP/IP. The `host` argument defaults to IP address 127.0.0.1 and `port` to 3306. Unix sockets are supported by setting `unix_socket`. Named pipes on the Windows platform are not supported.\n\nConnector/Python supports authentication plugins available as of MySQL 5.6. This includes `mysql_clear_password` and `sha256_password`, both of which require an SSL connection. The `sha256_password` plugin does not work over a non-SSL connection because Connector/Python does not support RSA encryption.\n\nThe `connect()` method supports an `auth_plugin` argument that can be used to force use of a particular plugin. For example, if the server is configured to use `sha256_password` by default and you want to connect to an account that authenticates using `mysql_native_password`, either connect using SSL or specify `auth_plugin='mysql_native_password'`.\n\n**Note**\n\nMySQL Connector/Python does not support the old, less-secure password protocols of MySQL versions prior to 4.1.\n\nConnector/Python supports the **Kerberos authentication protocol** for passwordless authentication. Linux clients are supported as of Connector/Python 8.0.26, and Windows support was added in Connector/Python 8.0.27 with the C extension implementation, and in Connector/Python 8.0.29 with the pure Python implementation. For Windows, the related `kerberos_auth_mode` connection option was added in 8.0.32 to configure the mode as either SSPI (default) or GSSAPI. While Windows supports both modes, Linux only supports GSSAPI.\nConnector/Python supports Multi-Factor Authentication (MFA) as of v8.0.28 by utilizing the password1 (alias of password), password2, and password3 connection options.\n\nConnector/Python supports FIDO Pluggable Authentication as of Connector/Python 8.0.29; an authentication mechanism added in MySQL Enterprise Edition 8.0.27.\n\nRestrictions: FIDO authentication functionality is only available in the C-extension implementation (installed by default); a NotSupportedError is raised when using the pure Python implementation of this connector. Also only a 2-level structure is supported, in that the connector and the physical key are on the same machine.\n\nSee FIDO Pluggable Authentication for installation details, and optionally use the Connector/Python fido_callback connection option to notify users that they need to touch the hardware device.\n\nCharacter Encoding\n\nBy default, strings coming from MySQL are returned as Python Unicode literals. To change this behavior, set use_unicode to False. You can change the character setting for the client connection through the charset argument. To change the character set after connecting to MySQL, set the charset property of the MySQLConnection instance. This technique is preferred over using the SET NAMES SQL statement directly. Similar to the charset property, you can set the collation for the current MySQL session.\n\nTransactions\n\nThe autocommit value defaults to False, so transactions are not automatically committed. Call the commit() method of the MySQLConnection instance within your application after doing a set of related insert, update, and delete operations. For data consistency and high throughput for write operations, it is best to leave the autocommit configuration option turned off when using InnoDB or other transactional tables.\n\nTime Zones\n\nThe time zone can be set per connection using the time_zone argument. This is useful, for example, if the MySQL server is set to UTC and TIMESTAMP values should be returned by MySQL converted to the PST time zone.\n\nSQL Modes\n\nMySQL supports so-called SQL Modes, which change the behavior of the server globally or per connection. For example, to have warnings raised as errors, set sql_mode to TRADITIONAL. For more information, see Server SQL Modes.\n\nTroubleshooting and Error Handling\n\nWarnings generated by queries are fetched automatically when get_warnings is set to True. You can also immediately raise an exception by setting raise_on_warnings to True. Consider using the MySQL sql_mode setting for turning warnings into errors.\n\nTo set a timeout value for connections, use connection_timeout.\n\nEnabling and Disabling Features Using Client Flags\n\nMySQL uses client flags to enable or disable features. Using the client_flags argument, you have control of what is set. To find out what flags are available, use the following:\n\n```python\nfrom mysql.connector.constants import ClientFlag\nprint '\\n'.join(ClientFlag.get_full_info())\n```\nIf `client_flags` is not specified (that is, it is zero), defaults are used for MySQL 4.1 and higher. If you specify an integer greater than 0, make sure all flags are set properly. A better way to set and unset flags individually is to use a list. For example, to set `FOUND_ROWS`, but disable the default `LONG_FLAG`:\n\n```python\nflags = [ClientFlag.FOUND_ROWS, ~ClientFlag.LONG_FLAG]\nmysql.connector.connect(client_flags=flags)\n```\n\n### Result Set Handling\n\nBy default, MySQL Connector/Python does not buffer or prefetch results. This means that after a query is executed, your program is responsible for fetching the data. This avoids excessive memory use when queries return large result sets. If you know that the result set is small enough to handle all at once, you can fetch the results immediately by setting `buffered` to `True`. It is also possible to set this per cursor (see Section 10.2.6, “MySQLConnection.cursor() Method”).\n\nResults generated by queries normally are not read until the client program fetches them. To automatically consume and discard result sets, set the `consume_results` option to `True`. The result is that all results are read, which for large result sets can be slow. (In this case, it might be preferable to close and reopen the connection.)\n\n### Type Conversions\n\nBy default, MySQL types in result sets are converted automatically to Python types. For example, a `DATETIME` column value becomes a `datetime.datetime` object. To disable conversion, set the `raw` option to `True`. You might do this to get better performance or perform different types of conversion yourself.\n\n### Connecting through SSL\n\nUsing SSL connections is possible when your Python installation supports SSL, that is, when it is compiled against the OpenSSL libraries. When you provide the `ssl_ca`, `ssl_key` and `ssl_cert` options, the connection switches to SSL, and the `client_flags` option includes the `ClientFlag.SSL` value automatically. You can use this in combination with the `compressed` option set to `True`.\n\nAs of Connector/Python 2.2.2, if the MySQL server supports SSL connections, Connector/Python attempts to establish a secure (encrypted) connection by default, falling back to an unencrypted connection otherwise.\n\nFrom Connector/Python 1.2.1 through Connector/Python 2.2.1, it is possible to establish an SSL connection using only the `ssl_ca` option. The `ssl_key` and `ssl_cert` arguments are optional. However, when either is given, both must be given or an `AttributeError` is raised.\n\n```python\n# Note (Example is valid for Python v2 and v3)\nfrom __future__ import print_function\nimport sys\n#sys.path.insert(0, 'python{0}/'.format(sys.version_info[0]))\nimport mysql.connector\nfrom mysql.connector.constants import ClientFlag\nconfig = {\n 'user': 'ssluser',\n 'password': 'password',\n 'host': '127.0.0.1',\n 'client_flags': [ClientFlag.SSL],\n 'ssl_ca': '/opt/mysql/ssl/ca.pem',\n 'ssl_cert': '/opt/mysql/ssl/client-cert.pem',\n 'ssl_key': '/opt/mysql/ssl/client-key.pem',\n}\n```\nConnection Pooling\n\nWith either the `pool_name` or `pool_size` argument present, Connector/Python creates the new pool. If the `pool_name` argument is not given, the `connect()` call automatically generates the name, composed from whichever of the `host`, `port`, `user`, and `database` connection arguments are given, in that order. If the `pool_size` argument is not given, the default size is 5 connections.\n\nThe `pool_reset_session` permits control over whether session variables are reset when the connection is returned to the pool. The default is to reset them.\n\nFor additional information about connection pooling, see Section 9.2, “Connector/Python Connection Pooling”.\n\nProtocol Compression\n\nThe boolean `compress` argument indicates whether to use the compressed client/server protocol (default `False`). This provides an easier alternative to setting the `ClientFlag.COMPRESS` flag. This argument is available as of Connector/Python 1.1.2.\n\nConverter Class\n\nThe `converter_class` argument takes a class and sets it when configuring the connection. An `AttributeError` is raised if the custom converter class is not a subclass of `conversion.MySQLConverterBase`.\n\nServer Failover\n\nThe `connect()` method accepts a `failover` argument that provides information to use for server failover in the event of connection failures. The argument value is a tuple or list of dictionaries (tuple is preferred because it is nonmutable). Each dictionary contains connection arguments for a given server in the failover sequence. Permitted dictionary values are: `user`, `password`, `host`, `port`, `unix_socket`, `database`, `pool_name`, `pool_size`. This failover option was added in Connector/Python 1.2.1.\n\nOption File Support\n\nAs of Connector/Python 2.0.0, option files are supported using two options for `connect()`:\n\n- `option_files`: Which option files to read. The value can be a file path name (a string) or a sequence of path name strings. By default, Connector/Python reads no option files, so this argument must be given explicitly to cause option files to be read. Files are read in the order specified.\n\n- `option_groups`: Which groups to read from option files, if option files are read. The value can be an option group name (a string) or a sequence of group name strings. If this argument is not given, the default value is `['client', 'connector_python']` to read the `client` and `connector_python` groups.\n\nFor more information, see Section 7.2, “Connector/Python Option-File Support”.\n\nLOAD DATA LOCAL INFILE\n\nPrior to Connector/Python 2.0.0, to enable use of `LOAD DATA LOCAL INFILE`, clients had to explicitly set the `ClientFlag.LOCAL_FILES` flag. As of 2.0.0, this flag is enabled by default. To disable it, the `allow_local_infile` connection option can be set to `False` at connect time (the default is `True`).\n\n```python\ncnx = mysql.connector.connect(**config)\ncur = cnx.cursor(buffered=True)\ncur.execute(\"SHOW STATUS LIKE 'Ssl_cipher'\")\nprint(cur.fetchone())\ncur.close()\ncnx.close()\n```\nCompatibility with Other Connection Interfaces\n\npasswd, db and connect_timeout are valid for compatibility with other MySQL interfaces and are respectively the same as password, database and connection_timeout. The latter take precedence. Data source name syntax or dsn is not used; if specified, it raises a NotSupportedError exception.\n\nClient/Server Protocol Implementation\n\nConnector/Python can use a pure Python interface to MySQL, or a C Extension that uses the MySQL C client library. The use_pure mysql.connector.connect() connection argument determines which. The default changed in Connector/Python 8 from True (use the pure Python implementation) to False. Setting use_pure changes the implementation used.\n\nThe use_pure argument is available as of Connector/Python 2.1.1. For more information about the C extension, see Chapter 8, The Connector/Python C Extension.\n\n7.2 Connector/Python Option-File Support\n\nAs of version 2.0.0, Connector/Python has the capability of reading options from option files. (For general information about option files in MySQL, see Using Option Files.) Two arguments for the connect() call control use of option files in Connector/Python programs:\n\n- **option_files**: Which option files to read. The value can be a file path name (a string) or a sequence of path name strings. By default, Connector/Python reads no option files, so this argument must be given explicitly to cause option files to be read. Files are read in the order specified.\n\n- **option_groups**: Which groups to read from option files, if option files are read. The value can be an option group name (a string) or a sequence of group name strings. If this argument is not given, the default value is ['client', 'connector_python'], to read the [client] and [connector_python] groups.\n\nConnector/Python also supports the !include and !includedir inclusion directives within option files. These directives work the same way as for other MySQL programs (see Using Option Files).\n\nThis example specifies a single option file as a string:\n\ncnx = mysql.connector.connect(option_files='/etc/mysql/connectors.cnf')\n\nThis example specifies multiple option files as a sequence of strings:\n\n```python\nmysql_option_files = [\n '/etc/mysql/connectors.cnf',\n './development.cnf',\n]\n\ncnx = mysql.connector.connect(option_files=mysql_option_files)\n```\n\nConnector/Python reads no option files by default, for backward compatibility with versions older than 2.0.0. This differs from standard MySQL clients such as mysql or mysqldump, which do read option files by default. To find out which option files the standard clients read on your system, invoke one of them with its --help option and examine the output. For example:\n\n```\n$> mysql --help\n...\nDefault options are read from the following files in the given order:\n/etc/my.cnf /etc/mysql/my.cnf /usr/local/mysql/etc/my.cnf ~/.my.cnf\n...\n```\n\nIf you specify the option_files connection argument to read option files, Connector/Python reads the [client] and [connector_python] option groups by default. To specify explicitly which groups to read, use the option_groups connection argument. The following example causes only the [connector_python] group to be read:\n\n```python\ncnx = mysql.connector.connect(option_files=mysql_option_files,\n option_groups=['connector_python'])\n```\ncnx = mysql.connector.connect(option_files='/etc/mysql/connectors.cnf',\n option_groups='connector_python')\n\nOther connection arguments specified in the `connect()` call take precedence over options read from option files. Suppose that `/etc/mysql/connectors.conf` contains these lines:\n\n```\n[client]\ndatabase=cpyapp\n```\n\nThe following `connect()` call includes no `database` connection argument. The resulting connection uses `cpyapp`, the database specified in the option file:\n\n```\ncnx = mysql.connector.connect(option_files='/etc/mysql/connectors.cnf')\n```\n\nBy contrast, the following `connect()` call specifies a default database different from the one found in the option file. The resulting connection uses `cpyapp_dev` as the default database, not `cpyapp`:\n\n```\ncnx2 = mysql.connector.connect(option_files='/etc/mysql/connectors.cnf',\n database='cpyapp_dev')\n```\n\nConnector/Python raises a `ValueError` if an option file cannot be read, or has already been read. This includes files read by inclusion directives.\n\nFor the `[connector_python]` group, only options supported by Connector/Python are accepted. Unrecognized options cause a `ValueError` to be raised.\n\nFor other option groups, Connector/Python ignores unrecognized options.\n\nIt is not an error for a named option group not to exist.\n\nConnector/Python treats option values in option files as strings and evaluates them using `eval()`. This enables specification of option values more complex than simple scalars.\nChapter 8 The Connector/Python C Extension\n\nTable of Contents\n\n8.1 Application Development with the Connector/Python C Extension ............................................. 33\n8.2 The _mysql_connector C Extension Module .............................................................................. 34\n\nConnector/Python supports a C extension that interfaces with the MySQL C client library. For queries that return large result sets, using the C Extension can improve performance compared to a “pure Python” implementation of the MySQL client/server protocol. Section 8.1, “Application Development with the Connector/Python C Extension”, describes how applications that use the mysql.connector module can use the C Extension. It is also possible to use the C Extension directly, by importing the _mysql_connector module rather than the mysql.connector module. See Section 8.2, “The _mysql_connector C Extension Module”. For information about installing the C Extension, see Chapter 4, Connector/Python Installation.\n\nNote\n\nThe C extension was added in version 2.1.1 and is enabled by default as of 8.0.11. The use_pure option determines whether the Python or C version of this connector is enabled and used.\n\n8.1 Application Development with the Connector/Python C Extension\n\nInstallations of Connector/Python from version 2.1.1 on support a use_pure argument to mysql.connector.connect() that indicates whether to use the pure Python interface to MySQL or the C Extension that uses the MySQL C client library:\n\n• By default, use_pure (use the pure Python implementation) is False as of MySQL 8 and defaults to True in earlier versions. If the C extension is not available on the system then use_pure is True.\n\n• On Linux, the C and Python implementations are available as different packages. You can install one or both implementations on the same system. On Windows and macOS, the packages include both implementations.\n\nFor Connector/Python installations that include both implementations, it can optionally be toggled it by passing use_pure=False (to use C implementation) or use_pure=True (to use the Python implementation) as an argument to mysql.connector.connect().\n\n• For Connector/Python installations that do not include the C Extension, passing use_pure=False to mysql.connector.connect() raises an exception.\n\n• For older Connector/Python installations that know nothing of the C Extension (before version 2.1.1), passing use_pure to mysql.connector.connect() raises an exception regardless of its value.\n\nNote\n\nOn macOS, if your Connector/Python installation includes the C Extension, but Python scripts are unable to use it, try setting your DYLD_LIBRARY_PATH environment variable the directory containing the C client library. For example:\n\nexport DYLD_LIBRARY_PATH=/usr/local/mysql/lib (for sh)\nsetenv DYLD_LIBRARY_PATH /usr/local/mysql/lib (for tcsh)\n\nIf you built the C Extension from source, this directory should be the one containing the C client library against which the extension was built.\nIf you need to check whether your Connector/Python installation is aware of the C Extension, test the `HAVE_CEXT` value. There are different approaches for this. Suppose that your usual arguments for `mysql.connector.connect()` are specified in a dictionary:\n\n```python\nconfig = {\n 'user': 'scott',\n 'password': 'password',\n 'host': '127.0.0.1',\n 'database': 'employees',\n}\n```\n\nThe following example illustrates one way to add `use_pure` to the connection arguments:\n\n```python\nimport mysql.connector\n\nif mysql.connector.__version_info__ > (2, 1) and mysql.connector.HAVE_CEXT:\n config['use_pure'] = False\n\nIf `use_pure=False` and the C Extension is not available, then Connector/Python will automatically fall back to the pure Python implementation.\n\n### 8.2 The `_mysql_connector` C Extension Module\n\nTo use the C Extension directly, import the `_mysql_connector` module rather than `mysql.connector`, then use the `_mysql_connector.MySQL()` class to obtain a `MySQL` instance. For example:\n\n```python\nimport _mysql_connector\n\nccnx = _mysql_connector.MySQL()\nccnx.connect(user='scott', password='password',\n host='127.0.0.1', database='employees')\nccnx.query(\"SHOW VARIABLES LIKE 'version%'\")\nrow = ccnx.fetch_row()\nwhile row:\n print(row)\n row = ccnx.fetch_row()\nccnx.free_result()\nccnx.close()\n```\n\nFor more information, see Chapter 11, *Connector/Python C Extension API Reference*. \n\n34\nChapter 9 Connector/Python Other Topics\n\nTable of Contents\n\n9.1 Connector/Python Logging ........................................................................................................... 35\n9.2 Connector/Python Connection Pooling .......................................................................................... 35\n9.3 Connector/Python Django Back End ............................................................................................... 37\n\nThis section describes additional Connection/Python features:\n\n• Connection pooling: Section 9.2, “Connector/Python Connection Pooling”\n• Django back end for MySQL: Section 9.3, “Connector/Python Django Back End”\n\n9.1 Connector/Python Logging\n\nBy default, logging functionality follows the default Python logging behavior. If logging functionality is not configured, only events with a severity level of WARNING and greater are printed to sys.stderr. For related information, see Python’s Configuring Logging for a Library documentation.\n\nOutputting additional levels requires configuration. For example, to output debug events to sys.stderr set logging.DEBUG and add the logging.StreamHandler handler. Additional handles can also be added, such as logging.FileHandler. This example sets both:\n\n```python\n# Classic Protocol Example\nimport logging\nimport mysql.connector\n\nlogger = logging.getLogger(\"mysql.connector\")\nlogger.setLevel(logging.DEBUG)\n\nformatter = logging.Formatter(\"%(asctime)s - %(name)s - %(levelname)s - %(message)s\")\n\nstream_handler = logging.StreamHandler()\nstream_handler.setFormatter(formatter)\nlogger.addHandler(stream_handler)\n\nfile_handler = logging.FileHandler(\"cpy.log\")\nfile_handler.setFormatter(formatter)\nlogger.addHandler(file_handler)\n\n# XDevAPI Protocol Example\nimport logging\nimport mysqlx\n\nlogger = logging.getLogger(\"mysqlx\")\nlogger.setLevel(logging.DEBUG)\n\nformatter = logging.Formatter(\"%(asctime)s - %(name)s - %(levelname)s - %(message)s\")\n\nstream_handler = logging.StreamHandler()\nstream_handler.setFormatter(formatter)\nlogger.addHandler(stream_handler)\n\nfile_handler = logging.FileHandler(\"cpy.log\")\nfile_handler.setFormatter(formatter)\nlogger.addHandler(file_handler)\n```\n\n9.2 Connector/Python Connection Pooling\n\nSimple connection pooling is supported that has these characteristics:\n\n• The mysql.connector.pooling module implements pooling.\nConnector/Python Connection Pooling\n\n- A pool opens a number of connections and handles thread safety when providing connections to requesters.\n\n- The size of a connection pool is configurable at pool creation time. It cannot be resized thereafter.\n\n- A connection pool can be named at pool creation time. If no name is given, one is generated using the connection parameters.\n\n- The connection pool name can be retrieved from the connection pool or connections obtained from it.\n\n- It is possible to have multiple connection pools. This enables applications to support pools of connections to different MySQL servers, for example.\n\n- For each connection request, the pool provides the next available connection. No round-robin or other scheduling algorithm is used. If a pool is exhausted, a `PoolError` is raised.\n\n- It is possible to reconfigure the connection parameters used by a pool. These apply to connections obtained from the pool thereafter. Reconfiguring individual connections obtained from the pool by calling the connection `config()` method is not supported.\n\nApplications that can benefit from connection-pooling capability include:\n\n- Middleware that maintains multiple connections to multiple MySQL servers and requires connections to be readily available.\n\n- Websites that can have more “permanent” connections open to the MySQL server.\n\nA connection pool can be created implicitly or explicitly.\n\n**To create a connection pool implicitly:** Open a connection and specify one or more pool-related arguments (`pool_name`, `pool_size`). For example:\n\n```python\ndbconfig = {\n \"database\": \"test\",\n \"user\": \"joe\"\n}\n\ncnx = mysql.connector.connect(pool_name = \"mypool\",\n pool_size = 3,\n **dbconfig)\n```\n\nThe pool name is restricted to alphanumeric characters and the special characters .,_, *, $, and #. The pool name must be no more than `pooling.CNX_POOL_MAXNAMESIZE` characters long (default 64).\n\nThe pool size must be greater than 0 and less than or equal to `pooling.CNX_POOL_MAXSIZE` (default 32).\n\nWith either the `pool_name` or `pool_size` argument present, Connector/Python creates the new pool. If the `pool_name` argument is not given, the `connect()` call automatically generates the name, composed from whichever of the host, port, user, and database connection arguments are given, in that order. If the `pool_size` argument is not given, the default size is 5 connections.\n\nSubsequent calls to `connect()` that name the same connection pool return connections from the existing pool. Any `pool_size` or connection parameter arguments are ignored, so the following `connect()` calls are equivalent to the original `connect()` call shown earlier:\n\n```python\ncnx = mysql.connector.connect(pool_name = \"mypool\", pool_size = 3)\ncnx = mysql.connector.connect(pool_name = \"mypool\", **dbconfig)\ncnx = mysql.connector.connect(pool_name = \"mypool\")\n```\n\nPooled connections obtained by calling `connect()` with a pool-related argument have a class of `PooledMySQLConnection` (see Section 10.4, “pooling.PooledMySQLConnection Class”).\nPooledMySQLConnection pooled connection objects are similar to MySQLConnection unpooled connection objects, with these differences:\n\n- To release a pooled connection obtained from a connection pool, invoke its close() method, just as for any unpooled connection. However, for a pooled connection, close() does not actually close the connection but returns it to the pool and makes it available for subsequent connection requests.\n\n- A pooled connection cannot be reconfigured using its config() method. Connection changes must be done through the pool object itself, as described shortly.\n\n- A pooled connection has a pool_name property that returns the pool name.\n\nTo create a connection pool explicitly: Create a MySQLConnectionPool object (see Section 10.3, \"pooling.MySQLConnectionPool Class\"):\n\n```python\ndbconfig = {\n \"database\": \"test\",\n \"user\": \"joe\"\n}\n\ncnxpool = mysql.connector.pooling.MySQLConnectionPool(pool_name = \"mypool\",\n pool_size = 3,\n **dbconfig)\n```\n\nTo request a connection from the pool, use its get_connection() method:\n\n```python\ncnx1 = cnxpool.get_connection()\ncnx2 = cnxpool.get_connection()\n```\n\nWhen you create a connection pool explicitly, it is possible to use the pool object's set_config() method to reconfigure the pool connection parameters:\n\n```python\ndbconfig = {\n \"database\": \"performance_schema\",\n \"user\": \"admin\",\n \"password\": \"password\"\n}\n\ncnxpool.set_config(**dbconfig)\n```\n\nConnections requested from the pool after the configuration change use the new parameters. Connections obtained before the change remain unaffected, but when they are closed (returned to the pool) are reopened with the new parameters before being returned by the pool for subsequent connection requests.\n\n9.3 Connector/Python Django Back End\n\nConnector/Python includes a mysql.connector.django module that provides a Django back end for MySQL. This back end supports new features found as of MySQL 5.6 such as fractional seconds support for temporal data types.\n\nDjango Configuration\n\nDjango uses a configuration file named settings.py that contains a variable called DATABASES (see https://docs.djangoproject.com/en/1.5/ref/settings/#std:setting-DATABASES). To configure Django to use Connector/Python as the MySQL back end, the example found in the Django manual can be used as a basis:\n\n```python\nDATABASES = {\n 'default': {\n 'NAME': 'user_data',\n 'ENGINE': 'mysql.connector.django',\n 'HOST': '127.0.0.1',\n 'PORT': 3306,\n```\nSupport for MySQL Features\n\nDjango can launch the MySQL client application `mysql`. When the Connector/Python back end does this, it arranges for the `sql_mode` system variable to be set to `TRADITIONAL` at startup.\n\nSome MySQL features are enabled depending on the server version. For example, support for fractional seconds precision is enabled when connecting to a server from MySQL 5.6.4 or higher. Django's `DateTimeField` is stored in a MySQL column defined as `DATETIME(6)`, and `TimeField` is stored as `TIME(6)`. For more information about fractional seconds support, see Fractional Seconds in Time Values.\n\nUsing a custom class for data type conversion is supported as a subclass of `mysql.connector.django.base.DjangoMySQLConverter`. This support was added in Connector/Python 8.0.29.\n\nIt is possible to add more connection arguments using `OPTIONS`.\n\n```python\n'USER': 'mysql_user',\n'PASSWORD': 'password',\n'OPTIONS': {\n 'autocommit': True,\n 'use_oure': True,\n 'init_command': \"SET foo='bar';\"\n},\n}\n```\n## Table of Contents\n\n10.1 mysql.connector Module ................................................................................. 41\n 10.1.1 mysql.connector.connect() Method ................................................................. 41\n 10.1.2 mysql.connector.api_level Property ................................................................. 41\n 10.1.3 mysql.connector.paramstyle Property ............................................................... 41\n 10.1.4 mysql.connector.threadsafety Property ............................................................ 42\n 10.1.5 mysql.connector.__version__ Property ............................................................... 42\n 10.1.6 mysql.connector.__version_info__ Property ....................................................... 42\n10.2 connection.MySQLConnection Class ................................................................. 42\n 10.2.1 connection.MySQLConnection() Constructor ..................................................... 42\n 10.2.2 MySQLConnection.close() Method ................................................................. 42\n 10.2.3 MySQLConnection.commit() Method ............................................................... 43\n 10.2.4 MySQLConnection.config() Method ............................................................... 43\n 10.2.5 MySQLConnection.connect() Method .............................................................. 43\n 10.2.6 MySQLConnection.cursor() Method ............................................................... 44\n 10.2.7 MySQLConnection.cmd_change_user() Method ............................................... 44\n 10.2.8 MySQLConnection.cmd_debug() Method ........................................................ 45\n 10.2.9 MySQLConnection.cmd_init_db() Method ....................................................... 45\n 10.2.10 MySQLConnection.cmd_ping() Method .......................................................... 45\n 10.2.11 MySQLConnection.cmd_process_info() Method .............................................. 45\n 10.2.12 MySQLConnection.cmd_process_kill() Method ............................................. 45\n 10.2.13 MySQLConnection.cmd_query() Method ....................................................... 45\n 10.2.14 MySQLConnection.cmd_query_iter() Method ................................................. 46\n 10.2.15 MySQLConnection.cmd_quit() Method .......................................................... 46\n 10.2.16 MySQLConnection.cmd_refresh() Method ..................................................... 46\n 10.2.17 MySQLConnection.cmd_reset_connection() Method ...................................... 47\n 10.2.18 MySQLConnection.cmd_shutdown() Method ................................................... 47\n 10.2.19 MySQLConnection.cmd_statistics() Method ................................................... 47\n 10.2.20 MySQLConnection.disconnect() Method ...................................................... 47\n 10.2.21 MySQLConnection.get_row() Method ........................................................... 47\n 10.2.22 MySQLConnection.get_rows() Method .......................................................... 47\n 10.2.23 MySQLConnection.get_server_info() Method ................................................. 48\n 10.2.24 MySQLConnection.get_server_version() Method ......................................... 48\n 10.2.25 MySQLConnection.is_connected() Method .................................................... 48\n 10.2.26 MySQLConnection.isset_client_flag() Method .............................................. 48\n 10.2.27 MySQLConnection.ping() Method ................................................................. 48\n 10.2.28 MySQLConnection.reconnect() Method ........................................................ 48\n 10.2.29 MySQLConnection.reset_session() Method .................................................. 49\n 10.2.30 MySQLConnection.rollback() Method .......................................................... 49\n 10.2.31 MySQLConnection.set_charset_collation() Method ...................................... 49\n 10.2.32 MySQLConnection.set_client_flags() Method .............................................. 50\n 10.2.33 MySQLConnection.shutdown() Method ........................................................ 50\n 10.2.34 MySQLConnection.start_transaction() Method .......................................... 50\n 10.2.35 MySQLConnection.autocommit Property ..................................................... 51\n 10.2.36 MySQLConnection.unread_results Property ................................................... 51\n 10.2.37 MySQLConnection.can_consume_results Property ........................................... 51\n 10.2.38 MySQLConnection.charset Property ........................................................... 51\n 10.2.39 MySQLConnection.connection_id Property .................................................... 51\n 10.2.40 MySQLConnection.connection_id Property .................................................... 51\n 10.2.41 MySQLConnection.database Property .......................................................... 52\n 10.2.42 MySQLConnection.get_warnings Property ................................................... 52\n 10.2.43 MySQLConnection.in_transaction Property ................................................... 52\n 10.2.44 MySQLConnection.raise_on_warnings Property ............................................. 52\n10.2.45 MySQLConnection.server_host Property .................................................. 53\n10.2.46 MySQLConnection.server_port Property .................................................. 53\n10.2.47 MySQLConnection.sql_mode Property ..................................................... 53\n10.2.48 MySQLConnection.time_zone Property .................................................. 53\n10.2.49 MySQLConnection.unix_socket Property ................................................ 54\n10.2.50 MySQLConnection.user Property ......................................................... 54\n\n10.3 pooling.MySQLConnectionPool Class ......................................................... 54\n10.3.1 pooling.MySQLConnectionPool Constructor .............................................. 54\n10.3.2 MySQLConnectionPool.add_connection() Method .................................. 54\n10.3.3 MySQLConnectionPool.get_connection() Method .................................. 55\n10.3.4 MySQLConnectionPool.set_config() Method ....................................... 55\n10.3.5 MySQLConnectionPool.pool_name Property ......................................... 55\n\n10.4 pooling.PooledMySQLConnection Class .................................................. 55\n10.4.1 pooling.PooledMySQLConnection Constructor .................................... 56\n10.4.2 PooledMySQLConnection.close() Method ............................................. 56\n10.4.3 PooledMySQLConnection.config() Method ......................................... 56\n10.4.4 PooledMySQLConnection.pool_name Property ..................................... 56\n\n10.5 cursor.MySQLCursor Class ........................................................................ 57\n10.5.1 cursor.MySQLCursor Constructor ......................................................... 57\n10.5.2 MySQLCursor.add_attribute() Method ................................................. 58\n10.5.3 MySQLCursor.clear_attributes() Method ............................................ 59\n10.5.4 MySQLCursor.get_attributes() Method .............................................. 59\n10.5.5 MySQLCursor.callproc() Method ....................................................... 59\n10.5.6 MySQLCursor.close() Method .............................................................. 60\n10.5.7 MySQLCursor.execute() Method ......................................................... 60\n10.5.8 MySQLCursor.fetchmany() Method ..................................................... 60\n10.5.9 MySQLCursor.fetchall() Method ......................................................... 61\n10.5.10 MySQLCursor.fetchone() Method ...................................................... 61\n10.5.11 MySQLCursor.fetchwarnings() Method ............................................ 62\n10.5.12 MySQLCursor.stored_results() Method ............................................. 62\n10.5.13 MySQLCursor.get_columns() Method ............................................... 63\n10.5.14 MySQLCursor.column_names Property .............................................. 63\n10.5.15 MySQLCursor.description Property .................................................. 63\n10.5.16 MySQLCursor.lastrowid Property ...................................................... 64\n10.5.17 MySQLCursor.rowcount Property ..................................................... 64\n10.5.18 MySQLCursor.statement Property ..................................................... 64\n10.5.19 MySQLCursor.with_rows Property ..................................................... 65\n\n10.6 Subclasses cursor.MySQLCursor ............................................................... 65\n10.6.1 cursor.MySQLCursorBufferedClass ..................................................... 65\n10.6.2 cursor.MySQLCursorRawClass ............................................................. 66\n10.6.3 cursor.MySQLCursorBufferedRawClass ............................................. 66\n10.6.4 cursor.MySQLCursorDictClass ............................................................. 66\n10.6.5 cursor.MySQLCursorBufferedDictClass ............................................. 67\n10.6.6 cursor.MySQLCursorNamedTupleClass .............................................. 67\n10.6.7 cursor.MySQLCursorBufferedNamedTupleClass .................................. 67\n10.6.8 cursor.MySQLCursorPreparedClass .................................................... 68\n\n10.7 constants.ClientFlag Class .......................................................................... 69\n10.8 constants.FieldType Class ........................................................................ 69\n10.9 constants.SQLMode Class ........................................................................... 70\n10.10 constants.CharacterSet Class ................................................................... 70\n10.11 constants.RefreshOption Class .................................................................. 70\n\n10.12 Errors and Exceptions ............................................................................. 70\n10.12.1 errorcode Module ................................................................................. 71\n10.12.2 errors.Error Exception ......................................................................... 72\n10.12.3 errors.DataError Exception .................................................................. 73\n10.12.4 errors.DatabaseError Exception ......................................................... 73\n10.12.5 errors.IntegrityError Exception ........................................................... 73\n10.12.6 errors.InterfaceError Exception .......................................................... 73\nThis chapter contains the public API reference for Connector/Python. Examples should be considered working for Python 2.7, and Python 3.1 and greater. They might also work for older versions (such as Python 2.4) unless they use features introduced in newer Python versions. For example, exception handling using the `as` keyword was introduced in Python 2.6 and will not work in Python 2.4.\n\nNote\n\nPython 2.7 support was removed in Connector/Python 8.0.24.\n\nThe following overview shows the `mysql.connector` package with its modules. Currently, only the most useful modules, classes, and methods for end users are documented.\n\n### 10.1 mysql.connector Module\n\nThe `mysql.connector` module provides top-level methods and properties.\n\n#### 10.1.1 mysql.connector.connect() Method\n\nThis method sets up a connection, establishing a session with the MySQL server. If no arguments are given, it uses the already configured or default values. For a complete list of possible arguments, see Section 7.1, \"Connector/Python Connection Arguments\".\n\nA connection with the MySQL server can be established using either the `mysql.connector.connect()` method or the `mysql.connector.MySQLConnection()` class:\n\n```python\ncnx = mysql.connector.connect(user='joe', database='test')\ncnx = MySQLConnection(user='joe', database='test')\n```\n\nFor descriptions of connection methods and properties, see Section 10.2, \"connection.MySQLConnection Class\".\n\n#### 10.1.2 mysql.connector.apilevel Property\n\nThis property is a string that indicates the supported DB API level.\n\n```python\n>>> mysql.connector.apilevel\n'2.0'\n```\n\n#### 10.1.3 mysql.connector.paramstyle Property\nThis property is a string that indicates the Connector/Python default parameter style.\n\n```python\n>>> mysql.connector.paramstyle\n'pyformat'\n```\n\n## 10.1.4 mysql.connector.threadsafety Property\n\nThis property is an integer that indicates the supported level of thread safety provided by Connector/Python.\n\n```python\n>>> mysql.connector.threadsafety\n1\n```\n\n## 10.1.5 mysql.connector.__version__ Property\n\nThis property indicates the Connector/Python version as a string. It is available as of Connector/Python 1.1.0.\n\n```python\n>>> mysql.connector.__version__\n'1.1.0'\n```\n\n## 10.1.6 mysql.connector.__version_info__ Property\n\nThis property indicates the Connector/Python version as an array of version components. It is available as of Connector/Python 1.1.0.\n\n```python\n>>> mysql.connector.__version_info__\n(1, 1, 0, 'a', 0)\n```\n\n### 10.2 connection.MySQLConnection Class\n\nThe `MySQLConnection` class is used to open and manage a connection to a MySQL server. It also used to send commands and SQL statements and read the results.\n\n#### 10.2.1 connection.MySQLConnection() Constructor\n\n**Syntax:**\n\n```python\ncnx = MySQLConnection(**kwargs)\n```\n\nThe `MySQLConnection` constructor initializes the attributes and when at least one argument is passed, it tries to connect to the MySQL server.\n\nFor a complete list of arguments, see Section 7.1, “Connector/Python Connection Arguments”.\n\n#### 10.2.2 MySQLConnection.close() Method\n\n**Syntax:**\n\n```python\ncnx.close()\n```\n\n`close()` is a synonym for `disconnect()`. See Section 10.2.20, “MySQLConnection.disconnect() Method”.\nFor a connection obtained from a connection pool, `close()` does not actually close it but returns it to the pool and makes it available for subsequent connection requests. See Section 9.2, “Connector/Python Connection Pooling”.\n\n### 10.2.3 MySQLConnection.commit() Method\n\nThis method sends a COMMIT statement to the MySQL server, committing the current transaction. Since by default Connector/Python does not autocommit, it is important to call this method after every transaction that modifies data for tables that use transactional storage engines.\n\n```python\n>>> cursor.execute(\"INSERT INTO employees (first_name) VALUES (%s), (%s)\", ('Jane', 'Mary'))\n>>> cnx.commit()\n```\n\nTo roll back instead and discard modifications, see the `rollback()` method.\n\n### 10.2.4 MySQLConnection.config() Method\n\n**Syntax:**\n\n```python\ncnx.config(**kwargs)\n```\n\nConfigures a `MySQLConnection` instance after it has been instantiated. For a complete list of possible arguments, see Section 7.1, “Connector/Python Connection Arguments”.\n\n**Arguments:**\n\n- `kwargs`: Connection arguments.\n\nYou could use the `config()` method to change (for example) the user name, then call `reconnect()`.\n\n**Example:**\n\n```python\ncnx = mysql.connector.connect(user='joe', database='test')\n# Connected as 'joe'\ncnx.config(user='jane')\ncnx.reconnect()\n# Now connected as 'jane'\n```\n\nFor a connection obtained from a connection pool, `config()` raises an exception. See Section 9.2, “Connector/Python Connection Pooling”.\n\n### 10.2.5 MySQLConnection.connect() Method\n\n**Syntax:**\n\n```python\nMySQLConnection.connect(**kwargs)\n```\n\nThis method sets up a connection, establishing a session with the MySQL server. If no arguments are given, it uses the already configured or default values. For a complete list of possible arguments, see Section 7.1, “Connector/Python Connection Arguments”.\n\n**Arguments:**\n\n- `kwargs`: Connection arguments.\n\n**Example:**\n\n```python\ncnx = MySQLConnection(user='joe', database='test')\n```\n\nFor a connection obtained from a connection pool, the connection object class is `PooledMySQLConnection`. A pooled connection differs from an unpooled connection as described in Section 9.2, “Connector/Python Connection Pooling”.\n\n43\n10.2.6 MySQLConnection.cursor() Method\n\nSyntax:\n```\ncursor = cnx.cursor([arg=value[, arg=value]...])\n```\n\nThis method returns a `MySQLCursor()` object, or a subclass of it depending on the passed arguments. The returned object is a `cursor.CursorBase` instance. For more information about cursor objects, see Section 10.5, “cursor.MySQLCursor Class”, and Section 10.6, “Subclasses cursor.MySQLCursor”.\n\nArguments may be passed to the `cursor()` method to control what type of cursor to create:\n\n- If `buffered` is True, the cursor fetches all rows from the server after an operation is executed. This is useful when queries return small result sets. `buffered` can be used alone, or in combination with the `dictionary` or `named_tuple` argument.\n\n `buffered` can also be passed to `connect()` to set the default buffering mode for all cursors created from the connection object. See Section 7.1, “Connector/Python Connection Arguments”.\n\n For information about the implications of buffering, see Section 10.6.1, “cursor.MySQLCursorBuffered Class”.\n\n- If `raw` is True, the cursor skips the conversion from MySQL data types to Python types when fetching rows. A raw cursor is usually used to get better performance or when you want to do the conversion yourself.\n\n `raw` can also be passed to `connect()` to set the default raw mode for all cursors created from the connection object. See Section 7.1, “Connector/Python Connection Arguments”.\n\n- If `dictionary` is True, the cursor returns rows as dictionaries. This argument is available as of Connector/Python 2.0.0.\n\n- If `named_tuple` is True, the cursor returns rows as named tuples. This argument is available as of Connector/Python 2.0.0.\n\n- If `prepared` is True, the cursor is used for executing prepared statements. This argument is available as of Connector/Python 1.1.2. The C extension supports this as of Connector/Python 8.0.17.\n\n- The `cursor_class` argument can be used to pass a class to use for instantiating a new cursor. It must be a subclass of `cursor.CursorBase`.\n\nThe returned object depends on the combination of the arguments. Examples:\n\n- If not `buffered` and not `raw`: `MySQLCursor`\n\n- If `buffered` and not `raw`: `MySQLCursorBuffered`\n\n- If not `buffered` and `raw`: `MySQLCursorRaw`\n\n- If `buffered` and `raw`: `MySQLCursorBufferedRaw`\n\n10.2.7 MySQLConnection.cmd_change_user() Method\n\nChanges the user using `username` and `password`. It also causes the specified `database` to become the default (current) database. It is also possible to change the character set using the `charset` argument.\n\nSyntax:\n```\ncnx.cmd_change_user(username='', password='', database='', charset=33)\n```\n\n44\n10.2.8 MySQLConnection.cmd_debug() Method\n\nInstructs the server to write debugging information to the error log. The connected user must have the SUPER privilege.\n\nReturns a dictionary containing the OK packet information.\n\n10.2.9 MySQLConnection.cmd_init_db() Method\n\nSyntax:\n```\ncnx.cmd_init_db(db_name)\n```\n\nThis method makes specified database the default (current) database. In subsequent queries, this database is the default for table references that include no explicit database qualifier.\n\nReturns a dictionary containing the OK packet information.\n\n10.2.10 MySQLConnection.cmd_ping() Method\n\nChecks whether the connection to the server is working.\n\nThis method is not to be used directly. Use ping() or is_connected() instead.\n\nReturns a dictionary containing the OK packet information.\n\n10.2.11 MySQLConnection.cmd_process_info() Method\n\nThis method raises the NotSupportedError exception. Instead, use the SHOW PROCESSLIST statement or query the tables found in the database INFORMATION_SCHEMA.\n\nDeprecation\nThis MySQL Server functionality is deprecated.\n\n10.2.12 MySQLConnection.cmd_process_kill() Method\n\nSyntax:\n```\ncnx.cmd_process_kill(mysql_pid)\n```\n\nDeprecation\nThis MySQL Server functionality is deprecated.\n\nAsks the server to kill the thread specified by mysql_pid. Although still available, it is better to use the KILL SQL statement.\n\nReturns a dictionary containing the OK packet information.\n\nThe following two lines have the same effect:\n```\n>>> cnx.cmd_process_kill(123)\n>>> cnx.cmd_query('KILL 123')\n```\n\n10.2.13 MySQLConnection.cmd_query() Method\n\nSyntax:\nMySQLConnection.cmd_query_iter() Method\n\nThis method sends the given statement to the MySQL server and returns a result. To send multiple statements, use the cmd_query_iter() method instead.\n\nThe returned dictionary contains information depending on what kind of query was executed. If the query is a SELECT statement, the result contains information about columns. Other statements return a dictionary containing OK or EOF packet information.\n\nErrors received from the MySQL server are raised as exceptions. An InterfaceError is raised when multiple results are found.\n\nReturns a dictionary.\n\n10.2.14 MySQLConnection.cmd_query_iter() Method\n\nSyntax:\n\n```python\ncnx.cmd_query_iter(statement)\n```\n\nSimilar to the cmd_query() method, but returns a generator object to iterate through results. Use cmd_query_iter() when sending multiple statements, and separate the statements with semicolons.\n\nThe following example shows how to iterate through the results after sending multiple statements:\n\n```python\nstatement = 'SELECT 1; INSERT INTO t1 VALUES (); SELECT 2'\nfor result in cnx.cmd_query_iter(statement):\n if 'columns' in result:\n columns = result['columns']\n rows = cnx.get_rows()\n else:\n # do something useful with INSERT result\n```\n\nReturns a generator object.\n\n10.2.15 MySQLConnection.cmd_quit() Method\n\nThis method sends a QUIT command to the MySQL server, closing the current connection. Since there is no response from the MySQL server, the packet that was sent is returned.\n\n10.2.16 MySQLConnection.cmd_refresh() Method\n\nSyntax:\n\n```python\ncnx.cmd_refresh(options)\n```\n\n**Deprecation**\n\nThis MySQL Server functionality is deprecated.\n\nThis method flushes tables or caches, or resets replication server information. The connected user must have the RELOAD privilege.\n\nThe options argument should be a bitmask value constructed using constants from the constants.RefreshOption class.\n\nFor a list of options, see Section 10.11, “constants.RefreshOption Class”.\n\nExample:\n10.2.17 MySQLConnection.cmd_reset_connection() Method\n\nSyntax:\n\n```python\ncnx.cmd_reset_connection()\n```\n\nResets the connection by sending a `COM_RESET_CONNECTION` command to the server to clear the session state.\n\nThis method permits the session state to be cleared without reauthenticating. For MySQL servers older than 5.7.3 (when `COM_RESET_CONNECTION` was introduced), the `reset_session()` method can be used instead. That method resets the session state by reauthenticating, which is more expensive.\n\nThis method was added in Connector/Python 1.2.1.\n\n10.2.18 MySQLConnection.cmd_shutdown() Method\n\n**Deprecation**\n\nThis MySQL Server functionality is deprecated.\n\nAsks the database server to shut down. The connected user must have the `SHUTDOWN` privilege.\n\nReturns a dictionary containing the OK packet information.\n\n10.2.19 MySQLConnection.cmd_statistics() Method\n\nReturns a dictionary containing information about the MySQL server including uptime in seconds and the number of running threads, questions, reloads, and open tables.\n\n10.2.20 MySQLConnection.disconnect() Method\n\nThis method tries to send a `QUIT` command and close the socket. It raises no exceptions.\n\nMySQLConnection.close() is a synonymous method name and more commonly used.\n\nTo shut down the connection without sending a `QUIT` command first, use `shutdown()`.\n\n10.2.21 MySQLConnection.get_row() Method\n\nThis method retrieves the next row of a query result set, returning a tuple.\n\nThe tuple returned by `get_row()` consists of:\n\n- The row as a tuple containing byte objects, or `None` when no more rows are available.\n- EOF packet information as a dictionary containing `status_flag` and `warning_count`, or `None` when the row returned is not the last row.\n\nThe `get_row()` method is used by `MySQLCursor` to fetch rows.\n\n10.2.22 MySQLConnection.get_rows() Method\n\nSyntax:\n\n```python\ncnx.get_rows(count=None)\n```\nThis method retrieves all or remaining rows of a query result set, returning a tuple containing the rows as sequences and the EOF packet information. The count argument can be used to obtain a given number of rows. If count is not specified or is `None`, all rows are retrieved.\n\nThe tuple returned by `get_rows()` consists of:\n- A list of tuples containing the row data as byte objects, or an empty list when no rows are available.\n- EOF packet information as a dictionary containing `status_flag` and `warning_count`.\n\nAn `InterfaceError` is raised when all rows have been retrieved.\n\n`MySQLCursor` uses the `get_rows()` method to fetch rows.\n\nReturns a tuple.\n\n### 10.2.23 `MySQLConnection.get_server_info()` Method\n\nThis method returns the MySQL server information verbatim as a string, for example `'5.6.11-log'`, or `None` when not connected.\n\n### 10.2.24 `MySQLConnection.get_server_version()` Method\n\nThis method returns the MySQL server version as a tuple, or `None` when not connected.\n\n### 10.2.25 `MySQLConnection.is_connected()` Method\n\nReports whether the connection to MySQL Server is available.\n\nThis method checks whether the connection to MySQL is available using the `ping()` method, but unlike `ping()`, `is_connected()` returns `True` when the connection is available, `False` otherwise.\n\n### 10.2.26 `MySQLConnection.isset_client_flag()` Method\n\nSyntax:\n\n```python\ncnx.isset_client_flag(flag)\n```\n\nThis method returns `True` if the client flag was set, `False` otherwise.\n\n### 10.2.27 `MySQLConnection.ping()` Method\n\nSyntax:\n\n```python\ncnx.ping(reconnect=False, attempts=1, delay=0)\n```\n\nCheck whether the connection to the MySQL server is still available.\n\nWhen `reconnect` is set to `True`, one or more `attempts` are made to try to reconnect to the MySQL server, and these options are forwarded to the `reconnect()` method. Use the `delay` argument (seconds) if you want to wait between each retry.\n\nWhen the connection is not available, an `InterfaceError` is raised. Use the `is_connected()` method to check the connection without raising an error.\n\nRaises `InterfaceError` on errors.\n\n### 10.2.28 `MySQLConnection.reconnect()` Method\n\nSyntax:\n**MySQLConnection.reset_session() Method**\n\nSyntax:\n\n```python\ncnx.reset_session(user_variables = None, session_variables = None)\n```\n\nResets the connection by reauthenticating to clear the session state. `user_variables`, if given, is a dictionary of user variable names and values. `session_variables`, if given, is a dictionary of system variable names and values. The method sets each variable to the given value.\n\nExample:\n\n```python\nuser_variables = {'var1': '1', 'var2': '10'}\nsession_variables = {'wait_timeout': 100000, 'sql_mode': 'TRADITIONAL'}\nself.cnx.reset_session(user_variables, session_variables)\n```\n\nThis method resets the session state by reauthenticating. For MySQL servers 5.7 or higher, the `cmd_reset_connection()` method is a more lightweight alternative.\n\nThis method was added in Connector/Python 1.2.1.\n\n**MySQLConnection.rollback() Method**\n\nThis method sends a `ROLLBACK` statement to the MySQL server, undoing all data changes from the current transaction. By default, Connector/Python does not autocommit, so it is possible to cancel transactions when using transactional storage engines such as InnoDB.\n\n```python\n>>> cursor.execute(\"INSERT INTO employees (first_name) VALUES (%s), (%s)\", ('Jane', 'Mary'))\n>>> cnx.rollback()\n```\n\nTo `commit` modifications, see the `commit()` method.\n\n**MySQLConnection.set_charset_collation() Method**\n\nSyntax:\n\n```python\ncnx.set_charset_collation(charset=None, collation=None)\n```\n\nThis method sets the character set and collation to be used for the current connection. The `charset` argument can be either the name of a character set, or the numerical equivalent as defined in `constants.CharacterSet`.\n\nWhen `collation` is `None`, the default collation for the character set is used.\n\nIn the following example, we set the character set to `latin1` and the collation to `latin1_swedish_ci` (the default collation for `latin1`):\n\n```python\n>>> cnx = mysql.connector.connect(user='scott')\n>>> cnx.set_charset_collation('latin1')\n```\nSpecify a given collation as follows:\n\n```python\n>>> cnx = mysql.connector.connect(user='scott')\n>>> cnx.set_charset_collation('latin1', 'latin1_general_ci')\n```\n\n### 10.2.32 MySQLConnection.set_client_flags() Method\n\n**Syntax:**\n\n```python\ncnx.set_client_flags(flags)\n```\n\nThis method sets the client flags to use when connecting to the MySQL server, and returns the new value as an integer. The `flags` argument can be either an integer or a sequence of valid client flag values (see Section 10.7, \"constants.ClientFlag Class\").\n\nIf `flags` is a sequence, each item in the sequence sets the flag when the value is positive or unsets it when negative. For example, to unset `LONG_FLAG` and set the `FOUND_ROWS` flags:\n\n```python\n>>> from mysql.connector.constants import ClientFlag\n>>> cnx.set_client_flags([ClientFlag.FOUND_ROWS, -ClientFlag.LONG_FLAG])\n>>> cnx.reconnect()\n```\n\n**Note**\n\nClient flags are only set or used when connecting to the MySQL server. It is therefore necessary to reconnect after making changes.\n\n### 10.2.33 MySQLConnection.shutdown() Method\n\nThis method closes the socket. It raises no exceptions.\n\nUnlike `disconnect()`, `shutdown()` closes the client connection without attempting to send a `QUIT` command to the server first. Thus, it will not block if the connection is disrupted for some reason such as network failure.\n\n`shutdown()` was added in Connector/Python 2.0.1.\n\n### 10.2.34 MySQLConnection.start_transaction() Method\n\nThis method starts a transaction. It accepts arguments indicating whether to use a consistent snapshot, which transaction isolation level to use, and the transaction access mode:\n\n```python\ncnx.start_transaction(consistent_snapshot=bool, isolation_level=level, readonly=access_mode)\n```\n\nThe default `consistent_snapshot` value is `False`. If the value is `True`, Connector/Python sends `WITH CONSISTENT_SNAPSHOT` with the statement. MySQL ignores this for isolation levels for which that option does not apply.\n\nThe default `isolation_level` value is `None`, and permitted values are 'READ UNCOMMITTED', 'READ COMMITTED', 'REPEATABLE READ', and 'SERIALIZABLE'. If the `isolation_level` value is `None`, no isolation level is sent, so the default level applies.\n\nThe `readonly` argument can be `True` to start the transaction in `READ ONLY` mode or `False` to start it in `READ WRITE` mode. If `readonly` is omitted, the server's default access mode is used. For details about transaction access mode, see the description for the `START TRANSACTION` statement at START TRANSACTION, COMMIT, and ROLLBACK Statements. If the server is older than MySQL 5.6.5, it does not support setting the access mode and Connector/Python raises a `ValueError`. \n\n---\n\n50\nInvoking `start_transaction()` raises a `ProgrammingError` if invoked while a transaction is currently in progress. This differs from executing a `START TRANSACTION` SQL statement while a transaction is in progress; the statement implicitly commits the current transaction.\n\nTo determine whether a transaction is active for the connection, use the `in_transaction` property.\n\n`start_transaction()` was added in MySQL Connector/Python 1.1.0. The `readonly` argument was added in Connector/Python 1.1.5.\n\n### 10.2.35 MySQLConnection.autocommit Property\n\nThis property can be assigned a value of `True` or `False` to enable or disable the autocommit feature of MySQL. The property can be invoked to retrieve the current autocommit setting.\n\n**Note**\n\nAutocommit is disabled by default when connecting through Connector/Python. This can be enabled using the `autocommit` connection parameter.\n\nWhen the autocommit is turned off, you must `commit` transactions when using transactional storage engines such as InnoDB or NDBCluster.\n\n```python\n>>> cnx.autocommit\nFalse\n>>> cnx.autocommit = True\n>>> cnx.autocommit\nTrue\n```\n\n### 10.2.36 MySQLConnection.unread_results Property\n\nIndicates whether there is an unread result. It is set to `False` if there is not an unread result, otherwise `True`. This is used by cursors to check whether another cursor still needs to retrieve its result set.\n\nDo not set the value of this property, as only the connector should change the value. In other words, treat this as a read-only property.\n\n### 10.2.37 MySQLConnection.can_consume_results Property\n\nThis property indicates the value of the `consume_results` connection parameter that controls whether result sets produced by queries are automatically read and discarded. See Section 7.1, “Connector/Python Connection Arguments”.\n\nThis method was added in Connector/Python 2.1.1.\n\n### 10.2.38 MySQLConnection.charset Property\n\nThis property returns a string indicating which character set is used for the connection, whether or not it is connected.\n\n### 10.2.39 MySQLConnection.collation Property\n\nThis property returns a string indicating which collation is used for the connection, whether or not it is connected.\n\n### 10.2.40 MySQLConnection.connection_id Property\n\nThis property returns the integer connection ID (thread ID or session ID) for the current connection or `None` when not connected.\n10.2.41 MySQLConnection.database Property\n\nThis property sets the current (default) database by executing a `USE` statement. The property can also be used to retrieve the current database name.\n\n```python\n>>> cnx.database = 'test'\n>>> cnx.database = 'mysql'\n>>> cnx.database\nu'mysql'\n```\n\nReturns a string.\n\n10.2.42 MySQLConnection.get_warnings Property\n\nThis property can be assigned a value of `True` or `False` to enable or disable whether warnings should be fetched automatically. The default is `False` (default). The property can be invoked to retrieve the current warnings setting.\n\nFetching warnings automatically can be useful when debugging queries. Cursors make warnings available through the method `MySQLCursor.fetchwarnings()`.\n\n```python\n>>> cnx.get_warnings = True\n>>> cursor.execute('SELECT \"a\"+1')\n>>> cursor.fetchall()\n[(1.0,)]\n>>> cursor.fetchwarnings()\n[(u'Warning', 1292, u'Truncated incorrect DOUBLE value: 'a'')]\n```\n\nReturns `True` or `False`.\n\n10.2.43 MySQLConnection.in_transaction Property\n\nThis property returns `True` or `False` to indicate whether a transaction is active for the connection. The value is `True` regardless of whether you start a transaction using the `start_transaction()` API call or by directly executing an SQL statement such as `START TRANSACTION` or `BEGIN`.\n\n```python\n>>> cnx.start_transaction()\n>>> cnx.in_transaction\nTrue\n>>> cnx.commit()\n>>> cnx.in_transaction\nFalse\n```\n\n`in_transaction` was added in MySQL Connector/Python 1.1.0.\n\n10.2.44 MySQLConnection.raise_on_warnings Property\n\nThis property can be assigned a value of `True` or `False` to enable or disable whether warnings should raise exceptions. The default is `False` (default). The property can be invoked to retrieve the current exceptions setting.\n\nSetting `raise_on_warnings` also sets `get_warnings` because warnings need to be fetched so they can be raised as exceptions.\n\nNote\nYou might always want to set the SQL mode if you would like to have the MySQL server directly report warnings as errors (see Section 10.2.47,\n“MySQLConnection.sql_mode Property”). It is also good to use transactional engines so transactions can be rolled back when catching the exception.\n\nResult sets needs to be fetched completely before any exception can be raised. The following example shows the execution of a query that produces a warning:\n\n```python\n>>> cnx.raise_on_warnings = True\n>>> cursor.execute('SELECT \"a\"+1')\n>>> cursor.fetchall()\n```\n\n```\nmysql.connector.errors.DataError: 1292: Truncated incorrect DOUBLE value: 'a'\n```\n\nReturns `True` or `False`.\n\n### 10.2.45 MySQLConnection.server_host Property\n\nThis read-only property returns the host name or IP address used for connecting to the MySQL server.\n\nReturns a string.\n\n### 10.2.46 MySQLConnection.server_port Property\n\nThis read-only property returns the TCP/IP port used for connecting to the MySQL server.\n\nReturns an integer.\n\n### 10.2.47 MySQLConnection.sql_mode Property\n\nThis property is used to retrieve and set the SQL Modes for the current connection. The value should be a list of different modes separated by comma (\",\") or a sequence of modes, preferably using the `constants.SQLMode` class.\n\nTo unset all modes, pass an empty string or an empty sequence.\n\n```python\n>>> cnx.sql_mode = 'TRADITIONAL,NO_ENGINE_SUBSTITUTION'\n>>> cnx.sql_mode.split(',,')\n[u'STRICT_TRANS_TABLES', u'STRICT_ALL_TABLES', u'NO_ZERO_IN_DATE', u'NO_ZERO_DATE', u'ERROR_FOR_DIVISION_BY_ZERO', u'TRADITIONAL', u'NO_AUTO_CREATE_USER', u'NO_ENGINE_SUBSTITUTION']\n>>> from mysql.connector.constants import SQLMode\n>>> cnx.sql_mode = [ SQLMode.NO_ZERO_DATE, SQLMode.REAL_AS_FLOAT]\n>>> cnx.sql_mode\nu'REAL_AS_FLOAT,NO_ZERO_DATE'\n```\n\nReturns a string.\n\n### 10.2.48 MySQLConnection.time_zone Property\n\nThis property is used to set or retrieve the time zone session variable for the current connection.\n\n```python\n>>> cnx.time_zone = '+00:00'\n>>> cursor = cnx.cursor()\n>>> cursor.execute('SELECT NOW()') ; cursor.fetchone()\n(datetime.datetime(2012, 6, 15, 11, 24, 36),)\n>>> cnx.time_zone = '-09:00'\n>>> cursor.execute('SELECT NOW()') ; cursor.fetchone()\n(datetime.datetime(2012, 6, 15, 2, 24, 44),)\n>>> cnx.time_zone\nu'-09:00'\n```\nMySQLConnection.unix_socket Property\n\nThis read-only property returns the Unix socket file for connecting to the MySQL server.\n\nReturns a string.\n\n10.2.50 MySQLConnection.user Property\n\nThis read-only property returns the user name used for connecting to the MySQL server.\n\nReturns a string.\n\n10.3 pooling.MySQLConnectionPool Class\n\nThis class provides for the instantiation and management of connection pools.\n\n10.3.1 pooling.MySQLConnectionPool Constructor\n\nSyntax:\n\n```\nMySQLConnectionPool(pool_name=None,\n pool_size=5,\n pool_reset_session=True,\n **kwargs)\n```\n\nThis constructor instantiates an object that manages a connection pool.\n\nArguments:\n\n- **pool_name**: The pool name. If this argument is not given, Connector/Python automatically generates the name, composed from whichever of the `host`, `port`, `user`, and `database` connection arguments are given in `kwargs`, in that order.\n\n It is not an error for multiple pools to have the same name. An application that must distinguish pools by their `pool_name` property should create each pool with a distinct name.\n\n- **pool_size**: The pool size. If this argument is not given, the default is 5.\n\n- **pool_reset_session**: Whether to reset session variables when the connection is returned to the pool. This argument was added in Connector/Python 1.1.5. Before 1.1.5, session variables are not reset.\n\n- **kwargs**: Optional additional connection arguments, as described in Section 7.1, “Connector/Python Connection Arguments”.\n\nExample:\n\n```\ndbconfig = {\n \"database\": \"test\",\n \"user\": \"joe\",\n}\n\ncnxpool = mysql.connector.pooling.MySQLConnectionPool(pool_name = \"mypool\",\n pool_size = 3,\n **dbconfig)\n```\n\n10.3.2 MySQLConnectionPool.add_connection() Method\n\nSyntax:\n\n```\ncnxpool.add_connection(cnx = None)\n```\nThis method adds a new or existing `MySQLConnection` to the pool, or raises a `PoolError` if the pool is full.\n\nArguments:\n\n- `cnx`: The `MySQLConnection` object to be added to the pool. If this argument is missing, the pool creates a new connection and adds it.\n\nExample:\n\n```python\n# add new connection to pool\ncnxpool.add_connection()\n# add existing connection to pool\ncnxpool.add_connection(cnx)\n```\n\n### 10.3.3 MySQLConnectionPool.get_connection() Method\n\n**Syntax:**\n\n```python\ncnxpool.get_connection()\n```\n\nThis method returns a connection from the pool, or raises a `PoolError` if no connections are available.\n\n**Example:**\n\n```python\ncnx = cnxpool.get_connection()\n```\n\n### 10.3.4 MySQLConnectionPool.set_config() Method\n\n**Syntax:**\n\n```python\ncnxpool.set_config(**kwargs)\n```\n\nThis method sets the configuration parameters for connections in the pool. Connections requested from the pool after the configuration change use the new parameters. Connections obtained before the change remain unaffected, but when they are closed (returned to the pool) are reopened with the new parameters before being returned by the pool for subsequent connection requests.\n\nArguments:\n\n- `kwargs`: Connection arguments.\n\n**Example:**\n\n```python\ndbconfig = {\n \"database\": \"performance_schema\",\n \"user\": \"admin\",\n \"password\": \"password\",\n}\n\ncnxpool.set_config(**dbconfig)\n```\n\n### 10.3.5 MySQLConnectionPool.pool_name Property\n\n**Syntax:**\n\n```python\ncnxpool.pool_name\n```\n\nThis property returns the connection pool name.\n\n**Example:**\n\n```python\nname = cnxpool.pool_name\n```\n\n### 10.4 pooling.PooledMySQLConnection Class\nThis class is used by `MySQLConnectionPool` to return a pooled connection instance. It is also the class used for connections obtained with calls to the `connect()` method that name a connection pool (see Section 9.2, “Connector/Python Connection Pooling”).\n\n`PooledMySQLConnection` pooled connection objects are similar to `MySQLConnection` unpoole connection objects, with these differences:\n\n- To release a pooled connection obtained from a connection pool, invoke its `close()` method, just as for any unpoole connection. However, for a pooled connection, `close()` does not actually close the connection but returns it to the pool and makes it available for subsequent connection requests.\n\n- A pooled connection cannot be reconfigured using its `config()` method. Connection changes must be done through the pool object itself, as described by Section 9.2, “Connector/Python Connection Pooling”.\n\n- A pooled connection has a `pool_name` property that returns the pool name.\n\n### 10.4.1 pooling.PooledMySQLConnection Constructor\n\n**Syntax:**\n\n```\nPooledMySQLConnection(cnxpool, cnx)\n```\n\nThis constructor takes connection pool and connection arguments and returns a pooled connection. It is used by the `MySQLConnectionPool` class.\n\n**Arguments:**\n\n- `cnxpool`: A `MySQLConnectionPool` instance.\n- `cnx`: A `MySQLConnection` instance.\n\n**Example:**\n\n```\npcnx = mysql.connector.pooling.PooledMySQLConnection(cnxpool, cnx)\n```\n\n### 10.4.2 PooledMySQLConnection.close() Method\n\n**Syntax:**\n\n```\ncnx.close()\n```\n\nReturns a pooled connection to its connection pool.\n\nFor a pooled connection, `close()` does not actually close it but returns it to the pool and makes it available for subsequent connection requests.\n\nIf the pool configuration parameters are changed, a returned connection is closed and reopened with the new configuration before being returned from the pool again in response to a connection request.\n\n### 10.4.3 PooledMySQLConnection.config() Method\n\nFor pooled connections, the `config()` method raises a `PoolError` exception. Configuration for pooled connections should be done using the pool object.\n\n### 10.4.4 PooledMySQLConnection.pool_name Property\n\n**Syntax:**\n\n```\ncnx.pool_name\n```\n\n---\n\n56\nThis property returns the name of the connection pool to which the connection belongs.\n\nExample:\n\n```python\ncnx = cnxpool.get_connection()\nname = cnx.pool_name\n```\n\n## 10.5 `cursor.MySQLCursor` Class\n\nThe `MySQLCursor` class instantiates objects that can execute operations such as SQL statements. Cursor objects interact with the MySQL server using a `MySQLConnection` object.\n\nTo create a cursor, use the `cursor()` method of a connection object:\n\n```python\nimport mysql.connector\ncnx = mysql.connector.connect(database='world')\ncursor = cnx.cursor()\n```\n\nSeveral related classes inherit from `MySQLCursor`. To create a cursor of one of these types, pass the appropriate arguments to `cursor()`:\n\n- **`MySQLCursorBuffered`** creates a buffered cursor. See Section 10.6.1, “cursor.MySQLCursorBuffered Class”.\n ```python\ncursor = cnx.cursor(buffered=True)\n```\n\n- **`MySQLCursorRaw`** creates a raw cursor. See Section 10.6.2, “cursor.MySQLCursorRaw Class”.\n ```python\ncursor = cnx.cursor(raw=True)\n```\n\n- **`MySQLCursorBufferedRaw`** creates a buffered raw cursor. See Section 10.6.3, “cursor.MySQLCursorBufferedRaw Class”.\n ```python\ncursor = cnx.cursor(raw=True, buffered=True)\n```\n\n- **`MySQLCursorDict`** creates a cursor that returns rows as dictionaries. See Section 10.6.4, “cursor.MySQLCursorDict Class”.\n ```python\ncursor = cnx.cursor(dictionary=True)\n```\n\n- **`MySQLCursorBufferedDict`** creates a buffered cursor that returns rows as dictionaries. See Section 10.6.5, “cursor.MySQLCursorBufferedDict Class”.\n ```python\ncursor = cnx.cursor(dictionary=True, buffered=True)\n```\n\n- **`MySQLCursorNamedTuple`** creates a cursor that returns rows as named tuples. See Section 10.6.6, “cursor.MySQLCursorNamedTuple Class”.\n ```python\ncursor = cnx.cursor(named_tuple=True)\n```\n\n- **`MySQLCursorBufferedNamedTuple`** creates a buffered cursor that returns rows as named tuples. See Section 10.6.7, “cursor.MySQLCursorBufferedNamedTuple Class”.\n ```python\ncursor = cnx.cursor(named_tuple=True, buffered=True)\n```\n\n- **`MySQLCursorPrepared`** creates a cursor for executing prepared statements. See Section 10.6.8, “cursor.MySQLCursorPrepared Class”.\n ```python\ncursor = cnx.cursor(prepared=True)\n```\n\n### 10.5.1 `cursor.MySQLCursor` Constructor\n\nIn most cases, the `MySQLConnection cursor()` method is used to instantiate a `MySQLCursor` object:\nimport mysql.connector\n\ncnx = mysql.connector.connect(database='world')\ncursor = cnx.cursor()\n\nIt is also possible to instantiate a cursor by passing a MySQLConnection object to MySQLCursor:\n\nimport mysql.connector\nfrom mysql.connector.cursor import MySQLCursor\n\ncnx = mysql.connector.connect(database='world')\ncursor = MySQLCursor(cnx)\n\nThe connection argument is optional. If omitted, the cursor is created but its `execute()` method raises an exception.\n\n## 10.5.2 MySQLCursor.add_attribute() Method\n\n**Syntax:**\n\n```python\ncursor.add_attribute(name, value)\n```\n\nAdds a new named query attribute to the list, as part of MySQL server's Query Attributes functionality.\n\n**name:** The name must be a string, but no other validation checks are made; attributes are sent as is to the server and errors, if any, will be detected and reported by the server.\n\n**value:** A value converted to the MySQL Binary Protocol, similar to how prepared statement parameters are converted. An error is reported if the conversion fails.\n\nQuery attributes must be enabled on the server, and are disabled by default. A warning is logged when setting query attributes server connection that does not support them. See also Prerequisites for Using Query Attributes for enabling the query_attributes MySQL server component.\n\nExample query attribute usage:\n\n```python\n# Each invocation of `add_attribute` method will add a new query attribute:\ncur.add_attribute(\"foo\", 2)\ncur.execute(\"SELECT first_name, last_name FROM clients\")\n# The query above sent attribute \"foo\" with value 2.\ncur.add_attribute(\"bar\", \"3\")\ncur.execute(\"SELECT * FROM products WHERE price < ?\", 10)\n# The query above sent attributes (\"foo\", 2) and (\"bar\", \"3\").\n\nmy_attributes = [(\"page_name\", \"root\"), (\"previous_page\", \"login\")]\nfor attribute_tuple in my_attributes:\n cur.add_attribute(*attribute_tuple)\ncur.execute(\"SELECT * FROM offers WHERE publish = ?\", 0)\n# The query above sent 4 attributes.\n\n# To check the current query attributes:\nprint(cur.get_attributes())\n# prints: [(\"foo\", 2), (\"bar\", \"3\"), (\"page_name\", \"root\"), (\"previous_page\", \"login\")]\n\n# Query attributes are not cleared until the cursor is closed or\n# of the clear_attributes() method is invoked:\ncur.clear_attributes()\nprint(cur.get_attributes())\n# prints: []\ncur.execute(\"SELECT first_name, last_name FROM clients\")\n# The query above did not send any attribute.\n```\n\nThis method was added in Connector/Python 8.0.26.\n10.5.3 MySQLCursor.clear_attributes() Method\n\nSyntax:\n\ncursor.clear_attributes()\n\nClear the list of query attributes on the connector’s side, as set by Section 10.5.2, “MySQLCursor.add_attribute() Method”.\n\nThis method was added in Connector/Python 8.0.26.\n\n10.5.4 MySQLCursor.get_attributes() Method\n\nSyntax:\n\ncursor.get_attributes()\n\nReturn a list of existing query attributes, as set by Section 10.5.2, “MySQLCursor.add_attribute() Method”.\n\nThis method was added in Connector/Python 8.0.26.\n\n10.5.5 MySQLCursor.callproc() Method\n\nSyntax:\n\ngerest_args = cursor.callproc(proc_name, args=())\n\nThis method calls the stored procedure named by the proc_name argument. The args sequence of parameters must contain one entry for each argument that the procedure expects. callproc() returns a modified copy of the input sequence. Input parameters are left untouched. Output and input/output parameters may be replaced with new values.\n\nResult sets produced by the stored procedure are automatically fetched and stored as MySQLCursorBuffered instances. For more information about using these result sets, see stored_results().\n\nSuppose that a stored procedure takes two parameters, multiplies the values, and returns the product:\n\nCREATE PROCEDURE multiply(IN pFac1 INT, IN pFac2 INT, OUT pProd INT)\nBEGIN\n SET pProd := pFac1 * pFac2;\nEND;\n\nThe following example shows how to execute the multiply() procedure:\n\n>>> args = (5, 6, 0) # 0 is to hold value of the OUT parameter pProd\n>>> cursor.callproc('multiply', args)\n('5', '6', 30L)\n\nConnector/Python 1.2.1 and up permits parameter types to be specified. To do this, specify a parameter as a two-item tuple consisting of the parameter value and type. Suppose that a procedure sp1() has this definition:\n\nCREATE PROCEDURE sp1(IN pStr1 VARCHAR(20), IN pStr2 VARCHAR(20),\nOUT pConCat VARCHAR(100))\nBEGIN\n SET pConCat := CONCAT(pStr1, pStr2);\nEND;\n\nTo execute this procedure from Connector/Python, specifying a type for the OUT parameter, do this:\n\nargs = (\"ham\", \"eggs\", (0, 'CHAR'))\nresult_args = cursor.callproc('sp1', args)\nprint(result_args[2])\n10.5.6 MySQLCursor.close() Method\n\nSyntax:\n```python\ncursor.close()\n```\n\nUse `close()` when you are done using a cursor. This method closes the cursor, resets all results, and ensures that the cursor object has no reference to its original connection object.\n\n10.5.7 MySQLCursor.execute() Method\n\nSyntax:\n```python\ncursor.execute(operation, params=None, multi=False)\n```\n\nThis method executes the given database operation (query or command). The parameters found in the tuple or dictionary `params` are bound to the variables in the operation. Specify variables using `%s` or `%(`name`)s` parameter style (that is, using format or pyformat style). `execute()` returns an iterator if `multi` is `True`.\n\nNote\n---\nIn Python, a tuple containing a single value must include a comma. For example, `(abc)` is evaluated as a scalar while `(abc,)` is evaluated as a tuple.\n\nThis example inserts information about a new employee, then selects the data for that person. The statements are executed as separate `execute()` operations:\n\n```python\ninsert_stmt = ('\"INSERT INTO employees (emp_no, first_name, last_name, hire_date) \"\n\"VALUES (%s, %s, %s, %s)\"')\ndata = (2, 'Jane', 'Doe', datetime.date(2012, 3, 23))\ncursor.execute(insert_stmt, data)\nselect_stmt = \"SELECT * FROM employees WHERE emp_no = %(emp_no)s\"\ncursor.execute(select_stmt, { 'emp_no': 2 })\n```\n\nThe data values are converted as necessary from Python objects to something MySQL understands. In the preceding example, the `datetime.date()` instance is converted to '2012-03-23'.\n\nIf `multi` is set to `True`, `execute()` is able to execute multiple statements specified in the `operation` string. It returns an iterator that enables processing the result of each statement. However, using parameters does not work well in this case, and it is usually a good idea to execute each statement on its own.\n\nThe following example selects and inserts data in a single `execute()` operation and displays the result of each statement:\n\n```python\noperation = 'SELECT 1; INSERT INTO t1 VALUES (); SELECT 2'\nfor result in cursor.execute(operation, multi=True):\n if result.with_rows:\n print(\"Rows produced by statement '{}':\".format(result.statement))\n print(result.fetchall())\n else:\n print(\"Number of rows affected by statement '{}': {}\".format(result.statement, result.rowcount))\n```\n\nIf the connection is configured to fetch warnings, warnings generated by the operation are available through the `MySQLCursor.fetchwarnings()` method.\n\n10.5.8 MySQLCursor.executemany() Method\nMySQLCursor.fetchall() Method\n\nSyntax:\n```\ncursor.fetchall()\n```\n\nThis method prepares a database operation (query or command) and executes it against all parameter sequences or mappings found in the sequence seq_of_params.\n\nNote\nIn Python, a tuple containing a single value must include a comma. For example, ('abc') is evaluated as a scalar while ('abc',) is evaluated as a tuple.\n\nIn most cases, the `executemany()` method iterates through the sequence of parameters, each time passing the current parameters to the `execute()` method.\n\nAn optimization is applied for inserts: The data values given by the parameter sequences are batched using multiple-row syntax. The following example inserts three records:\n\n```\ndata = [\n ('Jane', date(2005, 2, 12)),\n ('Joe', date(2006, 5, 23)),\n ('John', date(2010, 10, 3)),\n]\nstmt = \"INSERT INTO employees (first_name, hire_date) VALUES (%s, %s)\"\ncursor.executemany(stmt, data)\n```\n\nFor the preceding example, the `INSERT` statement sent to MySQL is:\n\n```\nINSERT INTO employees (first_name, hire_date) VALUES ('Jane', '2005-02-12'), ('Joe', '2006-05-23'), ('John', '2010-10-03')\n```\n\nWith the `executemany()` method, it is not possible to specify multiple statements to execute in the `operation` argument. Doing so raises an `InternalError` exception. Consider using `execute()` with `multi=True` instead.\n\n10.5.9 MySQLCursor.fetchall() Method\n\nSyntax:\n```\ncursor.fetchall()\n```\n\nThe method fetches all (or all remaining) rows of a query result set and returns a list of tuples. If no more rows are available, it returns an empty list.\n\nThe following example shows how to retrieve the first two rows of a result set, and then retrieve any remaining rows:\n\n```\n>>> cursor.execute(\"SELECT * FROM employees ORDER BY emp_no\")\n>>> head_rows = cursor.fetchmany(size=2)\n>>> remaining_rows = cursor.fetchall()\n```\n\nYou must fetch all rows for the current query before executing new statements using the same connection.\n\n10.5.10 MySQLCursor.fetchmany() Method\n\nSyntax:\n```\ncursor.fetchmany(size=1)\n```\n\nThis method fetches the next set of rows of a query result and returns a list of tuples. If no more rows are available, it returns an empty list.\n\nThe number of rows returned can be specified using the `size` argument, which defaults to one. Fewer rows are returned if fewer rows are available than specified.\nYou must fetch all rows for the current query before executing new statements using the same connection.\n\n10.5.11 MySQLCursor.fetchone() Method\n\nSyntax:\n\n```python\nrow = cursor.fetchone()\n```\n\nThis method retrieves the next row of a query result set and returns a single sequence, or `None` if no more rows are available. By default, the returned tuple consists of data returned by the MySQL server, converted to Python objects. If the cursor is a raw cursor, no such conversion occurs; see Section 10.6.2, “cursor.MySQLCursorRaw Class”.\n\nThe `fetchone()` method is used by `fetchall()` and `fetchmany()`. It is also used when a cursor is used as an iterator.\n\nThe following example shows two equivalent ways to process a query result. The first uses `fetchone()` in a `while` loop, the second uses the cursor as an iterator:\n\n```python\n# Using a while loop\ncursor.execute(\"SELECT * FROM employees\")\nrow = cursor.fetchone()\nwhile row is not None:\n print(row)\n row = cursor.fetchone()\n\n# Using the cursor as iterator\ncursor.execute(\"SELECT * FROM employees\")\nfor row in cursor:\n print(row)\n```\n\nYou must fetch all rows for the current query before executing new statements using the same connection.\n\n10.5.12 MySQLCursor.fetchwarnings() Method\n\nSyntax:\n\n```python\ntuples = cursor.fetchwarnings()\n```\n\nThis method returns a list of tuples containing warnings generated by the previously executed operation. To set whether to fetch warnings, use the connection's `get_warnings` property.\n\nThe following example shows a `SELECT` statement that generates a warning:\n\n```python\n>>> cnx.get_warnings = True\n>>> cursor.execute(\"SELECT 'a'+1\")\n>>> cursor.fetchall()\n[(1.0,)]\n>>> cursor.fetchwarnings()\n[(u'Warning', 1292, u\"Truncated incorrect DOUBLE value: 'a'\")]\n```\n\nWhen warnings are generated, it is possible to raise errors instead, using the connection's `raise_on_warnings` property.\n\n10.5.13 MySQLCursor.stored_results() Method\n\nSyntax:\n\n```python\niterator = cursor.stored_results()\n```\n\nThis method returns a list iterator object that can be used to process result sets produced by a stored procedure executed using the `callproc()` method. The result sets remain available until you use the cursor to execute another operation or call another stored procedure.\nThe following example executes a stored procedure that produces two result sets, then uses `stored_results()` to retrieve them:\n\n```python\n>>> cursor.callproc('myproc')\n() >>> for result in cursor.stored_results(): ...\n... print(result.fetchall()) ...\n... [{1,}] \n... [{2,}]\n```\n\n### 10.5.14 `MySQLCursor.column_names` Property\n\n**Syntax:**\n\n```python\nsequence = cursor.column_names\n```\n\nThis read-only property returns the column names of a result set as sequence of Unicode strings.\n\nThe following example shows how to create a dictionary from a tuple containing data with keys using `column_names`:\n\n```python\ncursor.execute(\"SELECT last_name, first_name, hire_date \"\n \"FROM employees WHERE emp_no = %s\", (123,))\nrow = dict(zip(cursor.column_names, cursor.fetchone()))\nprint(\"{last_name}, {first_name}: {hire_date}\").format(row)\n```\n\nAlternatively, as of Connector/Python 2.0.0, you can fetch rows as dictionaries directly; see Section 10.6.4, “cursor.MySQLCursorDict Class”.\n\n### 10.5.15 `MySQLCursor.description` Property\n\n**Syntax:**\n\n```python\ntuples = cursor.description\n```\n\nThis read-only property returns a list of tuples describing the columns in a result set. Each tuple in the list contains values as follows:\n\n```python\n(column_name, type, None, None, None, None, null_ok, column_flags)\n```\n\nThe following example shows how to interpret `description` tuples:\n\n```python\nimport mysql.connector\nfrom mysql.connector import FieldType\n...\nfor i in range(len(cursor.description)):\n print(\"Column {}:\").format(i+1))\n desc = cursor.description[i]\n print(\"column_name = {}\").format(desc[0]))\n print(\"type = {} ({})\").format(desc[1], FieldType.get_info(desc[1])))\n print(\"null_ok = {}\").format(desc[6]))\n print(\"column_flags = {}\").format(desc[7]))\n```\n\nThe output looks like this:\n\n```\nColumn 1:\n```\nThe `column_flags` value is an instance of the `constants.FieldFlag` class. To see how to interpret it, do this:\n\n```python\n>>> from mysql.connector import FieldFlag\n>>> FieldFlag.desc\n```\n\n### 10.5.16 MySQLCursor.lastrowid Property\n\n**Syntax:**\n\n```python\nid = cursor.lastrowid\n```\n\nThis read-only property returns the value generated for an `AUTO_INCREMENT` column by the previous `INSERT` or `UPDATE` statement or `None` when there is no such value available. For example, if you perform an `INSERT` into a table that contains an `AUTO_INCREMENT` column, `lastrowid` returns the `AUTO_INCREMENT` value for the new row. For an example, see Section 5.3, “Inserting Data Using Connector/Python”.\n\nThe `lastrowid` property is like the `mysql_insert_id()` C API function; see `mysql_insert_id()`.\n\n### 10.5.17 MySQLCursor.rowcount Property\n\n**Syntax:**\n\n```python\ncount = cursor.rowcount\n```\n\nThis read-only property returns the number of rows returned for `SELECT` statements, or the number of rows affected by DML statements such as `INSERT` or `UPDATE`. For an example, see Section 10.5.7, “MySQLCursor.execute() Method”.\n\nFor nonbuffered cursors, the row count cannot be known before the rows have been fetched. In this case, the number of rows is `-1` immediately after query execution and is incremented as rows are fetched.\n\nThe `rowcount` property is like the `mysql_affected_rows()` C API function; see `mysql_affected_rows()`.\n\n### 10.5.18 MySQLCursor.statement Property\n\n**Syntax:**\n\n```python\nstr = cursor.statement\n```\n\nThis read-only property returns the last executed statement as a string. The `statement` property can be useful for debugging and displaying what was sent to the MySQL server.\n\nThe string can contain multiple statements if a multiple-statement string was executed. This occurs for `execute()` with `multi=True`. In this case, the `statement` property contains the entire statement string and the `execute()` call returns an iterator that can be used to process results from the\nindividual statements. The `statement` property for this iterator shows statement strings for the individual statements.\n\n### 10.5.19 MySQLCursor.with_rows Property\n\nSyntax:\n\n```python\nboolean = cursor.with_rows\n```\n\nThis read-only property returns `True` or `False` to indicate whether the most recently executed operation could have produced rows.\n\nThe `with_rows` property is useful when it is necessary to determine whether a statement produces a result set and you need to fetch rows. The following example retrieves the rows returned by the `SELECT` statements, but reports only the affected-rows value for the `UPDATE` statement:\n\n```python\nimport mysql.connector\ncnx = mysql.connector.connect(user='scott', database='test')\ncursor = cnx.cursor()\noperation = 'SELECT 1; UPDATE t1 SET c1 = 2; SELECT 2'\nfor result in cursor.execute(operation, multi=True):\n if result.with_rows:\n result.fetchall()\n else:\n print(\"Number of affected rows: {}\".format(result.rowcount))\n```\n\n### 10.6 Subclasses cursor.MySQLCursor\n\nThe cursor classes described in the following sections inherit from the `MySQLCursor` class, which is described in Section 10.5, “cursor.MySQLCursor Class”.\n\n#### 10.6.1 cursor.MySQLCursorBuffered Class\n\nThe `MySQLCursorBuffered` class inherits from `MySQLCursor`.\n\nAfter executing a query, a `MySQLCursorBuffered` cursor fetches the entire result set from the server and buffers the rows.\n\nFor queries executed using a buffered cursor, row-fetching methods such as `fetchone()` return rows from the set of buffered rows. For nonbuffered cursors, rows are not fetched from the server until a row-fetching method is called. In this case, you must be sure to fetch all rows of the result set before executing any other statements on the same connection, or an `InternalError` (Unread result found) exception will be raised.\n\n`MySQLCursorBuffered` can be useful in situations where multiple queries, with small result sets, need to be combined or computed with each other.\n\nTo create a buffered cursor, use the `buffered` argument when calling a connection's `cursor()` method. Alternatively, to make all cursors created from the connection buffered by default, use the `buffered` connection argument.\n\nExample:\n\n```python\nimport mysql.connector\ncnx = mysql.connector.connect()\n# Only this particular cursor will buffer results\ncursor = cnx.cursor(buffered=True)\n\n# All cursors created from cnx2 will be buffered by default\ncnx2 = mysql.connector.connect(buffered=True)\n```\nFor a practical use case, see Section 6.1, “Tutorial: Raise Employee's Salary Using a Buffered Cursor”.\n\n10.6.2 cursor.MySQLCursorRaw Class\n\nThe MySQLCursorRaw class inherits from MySQLCursor.\n\nA MySQLCursorRaw cursor skips the conversion from MySQL data types to Python types when fetching rows. A raw cursor is usually used to get better performance or when you want to do the conversion yourself.\n\nTo create a raw cursor, use the raw argument when calling a connection's cursor() method. Alternatively, to make all cursors created from the connection raw by default, use the raw connection argument.\n\nExample:\n\n```python\nimport mysql.connector\ncnx = mysql.connector.connect()\n\n# Only this particular cursor will be raw\ncursor = cnx.cursor(raw=True)\n\n# All cursors created from cnx2 will be raw by default\ncnx2 = mysql.connector.connect(raw=True)\n```\n\n10.6.3 cursor.MySQLCursorBufferedRaw Class\n\nThe MySQLCursorBufferedRaw class inherits from MySQLCursor.\n\nA MySQLCursorBufferedRaw cursor is like a MySQLCursorRaw cursor, but is buffered: After executing a query, it fetches the entire result set from the server and buffers the rows. For information about the implications of buffering, see Section 10.6.1, “cursor.MySQLCursorBuffered Class”.\n\nTo create a buffered raw cursor, use the raw and buffered arguments when calling a connection's cursor() method. Alternatively, to make all cursors created from the connection raw and buffered by default, use the raw and buffered connection arguments.\n\nExample:\n\n```python\nimport mysql.connector\ncnx = mysql.connector.connect()\n\n# Only this particular cursor will be raw and buffered\ncursor = cnx.cursor(raw=True, buffered=True)\n\n# All cursors created from cnx2 will be raw and buffered by default\ncnx2 = mysql.connector.connect(raw=True, buffered=True)\n```\n\n10.6.4 cursor.MySQLCursorDict Class\n\nThe MySQLCursorDict class inherits from MySQLCursor. This class is available as of Connector/Python 2.0.0.\n\nA MySQLCursorDict cursor returns each row as a dictionary. The keys for each dictionary object are the column names of the MySQL result.\n\nExample:\n\n```python\ncnx = mysql.connector.connect(database='world')\ncursor = cnx.cursor(dictionary=True)\ncursor.execute(\"SELECT * FROM country WHERE Continent = 'Europe'\")\nprint(\"Countries in Europe:\")\n```\nfor row in cursor:\n print(\"* {Name}\".format(Name=row['Name']))\n\nThe preceding code produces output like this:\n\nCountries in Europe:\n* Albania\n* Andorra\n* Austria\n* Belgium\n* Bulgaria\n...\n\nIt may be convenient to pass the dictionary to `format()` as follows:\n\ncursor.execute(\"SELECT Name, Population FROM country WHERE Continent = 'Europe'\")\nprint(\"Countries in Europe with population:\")\nfor row in cursor:\n print(\"* {Name}: {Population}\".format(**row))\n\n### 10.6.5 cursor.MySQLCursorBufferedDict Class\n\nThe `MySQLCursorBufferedDict` class inherits from `MySQLCursor`. This class is available as of Connector/Python 2.0.0.\n\nA `MySQLCursorBufferedDict` cursor is like a `MySQLCursorDict` cursor, but is buffered: After executing a query, it fetches the entire result set from the server and buffers the rows. For information about the implications of buffering, see Section 10.6.1, “cursor.MySQLCursorBuffered Class”.\n\nTo get a buffered cursor that returns dictionaries, add the `buffered` argument when instantiating a new dictionary cursor:\n\ncursor = cnx.cursor(dictionary=True, buffered=True)\n\n### 10.6.6 cursor.MySQLCursorNamedTuple Class\n\nThe `MySQLCursorNamedTuple` class inherits from `MySQLCursor`. This class is available as of Connector/Python 2.0.0.\n\nA `MySQLCursorNamedTuple` cursor returns each row as a named tuple. The attributes for each named-tuple object are the column names of the MySQL result.\n\nExample:\n\ncnx = mysql.connector.connect(database='world')\ncursor = cnx.cursor(named_tuple=True)\ncursor.execute(\"SELECT * FROM country WHERE Continent = 'Europe'\")\nprint(\"Countries in Europe with population:\")\nfor row in cursor:\n print(\"* {Name}: {Population}\".format(\n Name=row.Name,\n Population=row.Population\n ))\n\n### 10.6.7 cursor.MySQLCursorBufferedNamedTuple Class\n\nThe `MySQLCursorBufferedNamedTuple` class inherits from `MySQLCursor`. This class is available as of Connector/Python 2.0.0.\n\nA `MySQLCursorBufferedNamedTuple` cursor is like a `MySQLCursorNamedTuple` cursor, but is buffered: After executing a query, it fetches the entire result set from the server and buffers the rows. For information about the implications of buffering, see Section 10.6.1, “cursor.MySQLCursorBuffered Class”.\nTo get a buffered cursor that returns named tuples, add the `buffered` argument when instantiating a new named-tuple cursor:\n\n```python\ncursor = cnx.cursor(named_tuple=True, buffered=True)\n```\n\n### 10.6.8 `cursor.MySQLCursorPrepared` Class\n\nThe `MySQLCursorPrepared` class inherits from `MySQLCursor`.\n\n**Note**\n\nThis class is available as of Connector/Python 1.1.0. The C extension supports it as of Connector/Python 8.0.17.\n\nIn MySQL, there are two ways to execute a prepared statement:\n\n- Use the `PREPARE` and `EXECUTE` statements.\n- Use the binary client/server protocol to send and receive data. To repeatedly execute the same statement with different data for different executions, this is more efficient than using `PREPARE` and `EXECUTE`. For information about the binary protocol, see C API Prepared Statement Interface.\n\nIn Connector/Python, there are two ways to create a cursor that enables execution of prepared statements using the binary protocol. In both cases, the `cursor()` method of the connection object returns a `MySQLCursorPrepared` object:\n\n- The simpler syntax uses a `prepared=True` argument to the `cursor()` method. This syntax is available as of Connector/Python 1.1.2.\n\n```python\nimport mysql.connector\n\n.cnx = mysql.connector.connect(database='employees')\ncursor = .cnx.cursor(prepared=True)\n```\n\n- Alternatively, create an instance of the `MySQLCursorPrepared` class using the `cursor_class` argument to the `cursor()` method. This syntax is available as of Connector/Python 1.1.0.\n\n```python\nimport mysql.connector\nfrom mysql.connector.cursor import MySQLCursorPrepared\n\ncnx = mysql.connector.connect(database='employees')\ncursor = cnx.cursor(cursor_class=MySQLCursorPrepared)\n```\n\nA cursor instantiated from the `MySQLCursorPrepared` class works like this:\n\n- The first time you pass a statement to the cursor’s `execute()` method, it prepares the statement. For subsequent invocations of `execute()`, the preparation phase is skipped if the statement is the same.\n- The `execute()` method takes an optional second argument containing a list of data values to associate with parameter markers in the statement. If the list argument is present, there must be one value per parameter marker.\n\n**Example:**\n\n```python\ncursor = cnx.cursor(prepared=True)\nstmt = \"SELECT fullname FROM employees WHERE id = %s\" # (1)\ncursor.execute(stmt, (5,)) # (2)\n# ... fetch data ...\ncursor.execute(stmt, (10,)) # (3)\n# ... fetch data ...\n```\n\n1. The `%s` within the statement is a parameter marker. Do not put quote marks around parameter markers.\n2. For the first call to the `execute()` method, the cursor prepares the statement. If data is given in the same call, it also executes the statement and you should fetch the data.\n\n3. For subsequent `execute()` calls that pass the same SQL statement, the cursor skips the preparation phase.\n\nPrepared statements executed with `MySQLCursorPrepared` can use the `format (%s)` or `qmark (?)` parameterization style. This differs from nonprepared statements executed with `MySQLCursor`, which can use the `format` or `pyformat` parameterization style.\n\nTo use multiple prepared statements simultaneously, instantiate multiple cursors from the `MySQLCursorPrepared` class.\n\nThe MySQL client/server protocol has an option to send prepared statement parameters via the `COM_STMT_SEND_LONG_DATA` command. To use this from Connector/Python scripts, send the parameter in question using the `IOBase` interface. Example:\n\n```python\nfrom io import IOBase\n...\ncur = cnx.cursor(prepared=True)\ncur.execute(\"SELECT (%s)\\n (io.BytesIO(bytes(\"A\", \"latin1\"))),\\n \")\n```\n\n### 10.7 constants.ClientFlag Class\n\nThis class provides constants defining MySQL client flags that can be used when the connection is established to configure the session. The `ClientFlag` class is available when importing `mysql.connector`.\n\n```python\n>>> import mysql.connector\n>>> mysql.connector.ClientFlag.FOUND_ROWS\n2\n```\n\nSee Section 10.2.32, “MySQLConnection.set_client_flags() Method” and the connection argument `client_flag`.\n\nThe `ClientFlag` class cannot be instantiated.\n\n### 10.8 constants.FieldType Class\n\nThis class provides all supported MySQL field or data types. They can be useful when dealing with raw data or defining your own converters. The field type is stored with every cursor in the description for each column.\n\nThe following example shows how to print the name of the data type for each column in a result set.\n\n```python\nfrom __future__ import print_function\nimport mysql.connector\nfrom mysql.connector import FieldType\n\ncnx = mysql.connector.connect(user='scott', database='test')\ncursor = cnx.cursor()\n\ncursor.execute(\"SELECT DATE(NOW()) AS \\\"c1\\\", TIME(NOW()) AS \\\"c2\\\", \"\n \\\"NOW() AS \\\"c3\\\", \\\"a string\\\" AS \\\"c4\\\", 42 AS \\\"c5\\\")\nrows = cursor.fetchall()\n\nfor desc in cursor.description:\n colname = desc[0]\n coltype = desc[1]\n```\nThe `FieldType` class cannot be instantiated.\n\n### 10.9 constants.SQLMode Class\n\nThis class provides all known MySQL Server SQL Modes. It is mostly used when setting the SQL modes at connection time using the connection's `sql_mode` property. See Section 10.2.47, “MySQLConnection.sql_mode Property”.\n\nThe `SQLMode` class cannot be instantiated.\n\n### 10.10 constants.CharacterSet Class\n\nThis class provides all known MySQL characters sets and their default collations. For examples, see Section 10.2.31, “MySQLConnection.set_charset_collation() Method”.\n\nThe `CharacterSet` class cannot be instantiated.\n\n### 10.11 constants.RefreshOption Class\n\nThis class performs various flush operations.\n\n- **RefreshOption.GRANT**\n \n Refresh the grant tables, like `FLUSH PRIVILEGES`.\n\n- **RefreshOption.LOG**\n \n Flush the logs, like `FLUSH LOGS`.\n\n- **RefreshOption.TABLES**\n \n Flush the table cache, like `FLUSH TABLES`.\n\n- **RefreshOption.HOSTS**\n \n Flush the host cache, like `FLUSH HOSTS`.\n\n- **RefreshOption.STATUS**\n \n Reset status variables, like `FLUSH STATUS`.\n\n- **RefreshOption.THREADS**\n \n Flush the thread cache.\n\n- **RefreshOption.REPLICA**\n \n On a replica replication server, reset the source server information and restart the replica, like `RESET SLAVE`. This constant was named \"RefreshOption.SLAVE\" before v8.0.23.\n\n### 10.12 Errors and Exceptions\n\nThe `mysql.connector.errors` module defines exception classes for errors and warnings raised by MySQL Connector/Python. Most classes defined in this module are available when you import `mysql.connector`. \nThe exception classes defined in this module mostly follow the Python Database API Specification v2.0 (PEP 249). For some MySQL client or server errors it is not always clear which exception to raise. It is good to discuss whether an error should be reclassified by opening a bug report.\n\nMySQL Server errors are mapped with Python exception based on their SQLSTATE value (see Server Error Message Reference). The following table shows the SQLSTATE classes and the exception Connector/Python raises. It is, however, possible to redefine which exception is raised for each server error. The default exception is `DatabaseError`.\n\n### Table 10.1 Mapping of Server Errors to Python Exceptions\n\n<table>\n<thead>\n<tr>\n<th>SQLSTATE Class</th>\n<th>Connector/Python Exception</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>02</td>\n<td><code>DataError</code></td>\n</tr>\n<tr>\n<td>07</td>\n<td><code>DatabaseError</code></td>\n</tr>\n<tr>\n<td>08</td>\n<td><code>OperationalError</code></td>\n</tr>\n<tr>\n<td>0A</td>\n<td><code>NotSupportedException</code></td>\n</tr>\n<tr>\n<td>21</td>\n<td><code>DataError</code></td>\n</tr>\n<tr>\n<td>22</td>\n<td><code>DataError</code></td>\n</tr>\n<tr>\n<td>23</td>\n<td><code>IntegrityError</code></td>\n</tr>\n<tr>\n<td>24</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>25</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>26</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>27</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>28</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>2A</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>2B</td>\n<td><code>DatabaseError</code></td>\n</tr>\n<tr>\n<td>2C</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>2D</td>\n<td><code>DatabaseError</code></td>\n</tr>\n<tr>\n<td>33</td>\n<td><code>DatabaseError</code></td>\n</tr>\n<tr>\n<td>34</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>35</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>37</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>3C</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>3D</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>3F</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>40</td>\n<td><code>InternalError</code></td>\n</tr>\n<tr>\n<td>42</td>\n<td><code>ProgrammingError</code></td>\n</tr>\n<tr>\n<td>44</td>\n<td><code>InternalError</code></td>\n</tr>\n<tr>\n<td>HZ</td>\n<td><code>OperationalError</code></td>\n</tr>\n<tr>\n<td>XA</td>\n<td><code>IntegrityError</code></td>\n</tr>\n<tr>\n<td>OK</td>\n<td><code>OperationalError</code></td>\n</tr>\n<tr>\n<td>HY</td>\n<td><code>DatabaseError</code></td>\n</tr>\n</tbody>\n</table>\n\n10.12.1 `errorcode` Module\nThis module contains both MySQL server and client error codes defined as module attributes with the error number as value. Using error codes instead of error numbers could make reading the source code a bit easier.\n\n>>> from mysql.connector import errorcode\n>>> errorcode.ER_BAD_TABLE_ERROR\n1051\n\nFor more information about MySQL errors, see Error Messages and Common Problems.\n\n10.12.2 errors.Error Exception\n\nThis exception is the base class for all other exceptions in the errors module. It can be used to catch all errors in a single except statement.\n\nThe following example shows how we could catch syntax errors:\n\n```python\nimport mysql.connector\ntry:\n cnx = mysql.connector.connect(user='scott', database='employees')\n cursor = cnx.cursor()\n cursor.execute(\"SELECT * FROM employees\") # Syntax error in query\n cnx.close()\nexcept mysql.connector.Error as err:\n print(\"Something went wrong: {}\".format(err))\n```\n\nInitializing the exception supports a few optional arguments, namely msg, errno, values and sqlstate. All of them are optional and default to None. errors.Error is internally used by Connector/Python to raise MySQL client and server errors and should not be used by your application to raise exceptions.\n\nThe following examples show the result when using no arguments or a combination of the arguments:\n\n```python\n>>> from mysql.connector.errors import Error\n>>> str(Error())\n'Unknown error'\n>>> str(Error(\"Oops! There was an error.\"))\n'Oops! There was an error.'\n>>> str(Error(errno=2006))\n'2006: MySQL server has gone away'\n>>> str(Error(errno=2002, values=(\"/tmp/mysql.sock\", 2)))\n'2002: Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)'\n>>> str(Error(errno=1146, sqlstate='42S02', msg=\"Table 'test.spam' doesn't exist\"))\n'1146 (42S02): Table 'test.spam' doesn't exist'\n```\n\nThe example which uses error number 1146 is used when Connector/Python receives an error packet from the MySQL Server. The information is parsed and passed to the Error exception as shown.\n\nEach exception subclassing from Error can be initialized using the previously mentioned arguments. Additionally, each instance has the attributes errno, msg and sqlstate which can be used in your code.\n\nThe following example shows how to handle errors when dropping a table which does not exist (when the DROP TABLE statement does not include a IF EXISTS clause):\n\n```python\nimport mysql.connector\nfrom mysql.connector import errorcode\n```\nPrior to Connector/Python 1.1.1, the original message passed to `errors.Error()` is not saved in such a way that it could be retrieved. Instead, the `Error.msg` attribute was formatted with the error number and SQLSTATE value. As of 1.1.1, only the original message is saved in the `Error.msg` attribute. The formatted value together with the error number and SQLSTATE value can be obtained by printing or getting the string representation of the error object. Example:\n\n```\ntry:\n conn = mysql.connector.connect(database = \"baddb\")\nexcept mysql.connector.Error as e:\n print \"Error code:\", e.errno # error number\n print \"SQLSTATE value:\", e.sqlstate # SQLSTATE value\n print \"Error message:\", e.msg # error message\n s = str(e)\n print \"Error: \", s # errno, sqlstate, msg values\n```\n\n`errors.Error` is a subclass of the Python `StandardError`.\n\n### 10.12.3 errors.DataError Exception\n\nThis exception is raised when there were problems with the data. Examples are a column set to `NULL` that cannot be `NULL`, out-of-range values for a column, division by zero, column count does not match value count, and so on.\n\n`errors.DataError` is a subclass of `errors.DatabaseError`.\n\n### 10.12.4 errors.DatabaseError Exception\n\nThis exception is the default for any MySQL error which does not fit the other exceptions.\n\n`errors.DatabaseError` is a subclass of `errors.Error`.\n\n### 10.12.5 errors.IntegrityError Exception\n\nThis exception is raised when the relational integrity of the data is affected. For example, a duplicate key was inserted or a foreign key constraint would fail.\n\nThe following example shows a duplicate key error raised as IntegrityError:\n\n```\ncursor.execute(\"CREATE TABLE t1 (id int, PRIMARY KEY (id))\")\ntry:\n cursor.execute(\"INSERT INTO t1 (id) VALUES (1)\")\n cursor.execute(\"INSERT INTO t1 (id) VALUES (1)\")\nexcept mysql.connector.IntegrityError as err:\n print(\"Error: {}\".format(err))\n```\n\n`errors.IntegrityError` is a subclass of `errors.DatabaseError`.\n\n### 10.12.6 errors.InterfaceError Exception\n\nThis exception is raised for errors originating from Connector/Python itself, not related to the MySQL server.\n\n`errors.InterfaceError` is a subclass of `errors.Error`.\n10.12.7 errors.InternalError Exception\n\nThis exception is raised when the MySQL server encounters an internal error, for example, when a\ndeadlock occurred.\n\nerrors.InternalError is a subclass of errors.DatabaseError.\n\n10.12.8 errors.NotSupportedError Exception\n\nThis exception is raised when some feature was used that is not supported by the version of MySQL\nthat returned the error. It is also raised when using functions or statements that are not supported by\nstored routines.\n\nerrors.NotSupportedError is a subclass of errors.DatabaseError.\n\n10.12.9 errors.OperationalError Exception\n\nThis exception is raised for errors which are related to MySQL's operations. For example: too\nmany connections; a host name could not be resolved; bad handshake; server is shutting down,\ncommunication errors.\n\nerrors.OperationalError is a subclass of errors.DatabaseError.\n\n10.12.10 errors.PoolError Exception\n\nThis exception is raised for connection pool errors.\n\nerrors.PoolError is a subclass of errors.Error.\n\n10.12.11 errors.ProgrammingError Exception\n\nThis exception is raised on programming errors, for example when you have a syntax error in your SQL\nor a table was not found.\n\nThe following example shows how to handle syntax errors:\n\n```python\ntry:\n cursor.execute(\"CREATE DESK t1 (id int, PRIMARY KEY (id))\")\nexcept mysql.connector.ProgrammingError as err:\n if err.errno == errorcode.ER_SYNTAX_ERROR:\n print(\"Check your syntax!\")\n else:\n print(\"Error: {}\".format(err))\n```\n\nerrors.ProgrammingError is a subclass of errors.DatabaseError.\n\n10.12.12 errors.Warning Exception\n\nThis exception is used for reporting important warnings, however, Connector/Python does not use it. It\nis included to be compliant with the Python Database Specification v2.0 (PEP-249).\n\nConsider using either more strict Server SQL Modes or the raise_on_warnings connection argument to\nmake Connector/Python raise errors when your queries produce warnings.\n\nerrors.Warning is a subclass of the Python StandardError.\n\n10.12.13 errors.custom_error_exception() Function\n\nSyntax:\n\n```python\nerrors.custom_error_exception(error=None, exception=None)\n```\nThis method defines custom exceptions for MySQL server errors and returns current customizations.\n\nIf `error` is a MySQL Server error number, you must also pass the `exception` class. The `error` argument can be a dictionary, in which case the key is the server error number, and value the class of the exception to be raised.\n\nTo reset the customizations, supply an empty dictionary.\n\n```python\nimport mysql.connector\nfrom mysql.connector import errorcode\n\n# Server error 1028 should raise a DatabaseError\nmysql.connector.custom_error_exception(1028, mysql.connector.DatabaseError)\n\n# Or using a dictionary:\nmysql.connector.custom_error_exception({\n 1028: mysql.connector.DatabaseError,\n 1029: mysql.connector.OperationalError,\n})\n\n# To reset, pass an empty dictionary:\nmysql.connector.custom_error_exception({})\n```\nChapter 11 Connector/Python C Extension API Reference\n\nTable of Contents\n\n11.1 _mysql.connector Module ........................................................................................................ 78\n11.2 _mysql.connector.MySQL() Class .............................................................................................. 78\n11.3 _mysql.connector.MySQL.affected_rows() Method .................................................................. 78\n11.4 _mysql.connector.MySQL.autocommit() Method ..................................................................... 78\n11.5 _mysql.connector.MySQL.buffered() Method .......................................................................... 79\n11.6 _mysql.connector.MySQL.change_user() Method .................................................................. 79\n11.7 _mysql.connector.MySQL.character_set_name() Method ......................................................... 79\n11.8 _mysql.connector.MySQL.close() Method ................................................................................. 79\n11.9 _mysql.connector.MySQL.commit() Method .............................................................................. 79\n11.10 _mysql.connector.MySQL.connect() Method ......................................................................... 79\n11.11 _mysql.connector.MySQL.connected() Method ...................................................................... 80\n11.12 _mysql.connector.MySQL.consume_result() Method ............................................................. 80\n11.13 _mysql.connector.MySQL.convert_to_mysql() Method .......................................................... 80\n11.14 _mysql.connector.MySQL.escape_string() Method ................................................................. 80\n11.15 _mysql.connector.MySQL.fetch_fields() Method .................................................................. 81\n11.16 _mysql.connector.MySQL.fetchall() Method ........................................................................ 81\n11.17 _mysql.connector.MySQL.field_count() Method .................................................................... 81\n11.18 _mysql.connector.MySQL.free_result() Method .................................................................... 81\n11.19 _mysql.connector.MySQL.get_character_set_info() Method ................................................ 81\n11.20 _mysql.connector.MySQL.get_client_info() Method ............................................................ 81\n11.21 _mysql.connector.MySQL.get_client_version() Method ........................................................ 82\n11.22 _mysql.connector.MySQL.get_connection() Method .............................................................. 82\n11.23 _mysql.connector.MySQL.get_proto_info() Method .............................................................. 82\n11.24 _mysql.connector.MySQL.get_server_info() Method ............................................................. 82\n11.25 _mysql.connector.MySQL.get_server_version() Method ....................................................... 82\n11.26 _mysql.connector.MySQL.get_ssl_cipher() Method ............................................................... 82\n11.27 _mysql.connector.MySQL.hex_string() Method ..................................................................... 82\n11.28 _mysql.connector.MySQL.insert_id() Method ....................................................................... 83\n11.29 _mysql.connector.MySQL.more_results() Method .................................................................. 83\n11.30 _mysql.connector.MySQL.next_result() Method .................................................................. 83\n11.31 _mysql.connector.MySQL.num_fields() Method .................................................................... 83\n11.32 _mysql.connector.MySQL.num_rows() Method ...................................................................... 83\n11.33 _mysql.connector.MySQL.ping() Method ................................................................................. 83\n11.34 _mysql.connector.MySQL.query() Method ............................................................................. 83\n11.35 _mysql.connector.MySQL.raw() Method ................................................................................ 84\n11.36 _mysql.connector.MySQL.refresh() Method .......................................................................... 84\n11.37 _mysql.connector.MySQL.reset_connection() Method ........................................................... 84\n11.38 _mysql.connector.MySQL.rollback() Method ....................................................................... 84\n11.39 _mysql.connector.MySQL.select_db() Method ..................................................................... 84\n11.40 _mysql.connector.MySQL.set_character_set() Method .......................................................... 85\n11.41 _mysql.connector.MySQL.shutdown() Method ...................................................................... 85\n11.42 _mysql.connector.MySQL.stat() Method ................................................................................ 85\n11.43 _mysql.connector.MySQL.thread_id() Method ...................................................................... 85\n11.44 _mysql.connector.MySQL.use_unicode() Method ................................................................... 85\n11.45 _mysql.connector.MySQL.warning_count() Method ............................................................... 86\n11.46 _mysql.connector.MySQL.have_result_set Property ............................................................ 86\n\nThis chapter contains the public API reference for the Connector/Python C Extension, also known as the _mysql.connector Python module.\n\nThe _mysql.connector C Extension module can be used directly without any other code of Connector/Python. One reason to use this module directly is for performance reasons.\n11.1 _mysql_connector Module\n\nThe _mysql_connector module provides classes.\n\n11.2 _mysql_connector.MySQL() Class\n\nSyntax:\n\n```python\nccnx = _mysql_connector.MySQL(args)\n```\n\nThe MySQL class is used to open and manage a connection to a MySQL server (referred to elsewhere in this reference as “the MySQL instance”). It is also used to send commands and SQL statements and read results.\n\nThe MySQL class wraps most functions found in the MySQL C Client API and adds some additional convenient functionality.\n\n```python\nimport _mysql_connector\nccnx = _mysql_connector.MySQL()\nccnx.connect(user='scott', password='password',\nhost='127.0.0.1', database='employees')\nccnx.close()\n```\n\nPermitted arguments for the MySQL class are auth_plugin, buffered, charset_name, connection_timeout, raw, use_unicode. Those arguments correspond to the arguments of the same names for MySQLConnection.connect() as described at Section 7.1, “Connector/Python Connection Arguments”, except that charset_name corresponds to charset.\n\n11.3 _mysql_connector.MySQL.affected_rows() Method\n\nSyntax:\n\n```python\ncount = ccnx.affected_rows()\n```\n\nReturns the number of rows changed, inserted, or deleted by the most recent UPDATE, INSERT, or DELETE statement.\n\n11.4 _mysql_connector.MySQL.autocommit() Method\n\nSyntax:\n\n```python\nccnx.autocommit(bool)\n```\n\nSets the autocommit mode.\n11.5 _mysql_connector.MySQL.buffered() Method\n\nSyntax:\n\n```python\nis_buffered = ccnx.buffered() # getter\nccnx.buffered(bool) # setter\n```\n\nWith no argument, returns `True` or `False` to indicate whether the MySQL instance buffers (stores) the results.\n\nWith a boolean argument, sets the MySQL instance buffering mode.\n\nFor the setter syntax, raises a `TypeError` exception if the value is not `True` or `False`.\n\n11.6 _mysql_connector.MySQL.change_user() Method\n\nSyntax:\n\n```python\nccnx.change_user(user='user_name', password='password_val', database='db_name')\n```\n\nChanges the user and sets a new default database. Permitted arguments are `user`, `password`, and `database`.\n\n11.7 _mysql_connector.MySQL.character_set_name() Method\n\nSyntax:\n\n```python\ncharset = ccnx.character_set_name()\n```\n\nReturns the name of the default character set for the current MySQL session.\n\nSome MySQL character sets have no equivalent names in Python. When this is the case, a name usable by Python is returned. For example, the 'utf8mb4' MySQL character set name is returned as 'utf8'.\n\n11.8 _mysql_connector.MySQL.close() Method\n\nSyntax:\n\n```python\nccnx.close()\n```\n\nCloses the MySQL connection.\n\n11.9 _mysql_connector.MySQL.commit() Method\n\nSyntax:\n\n```python\nccnx.commit()\n```\n\nCommits the current transaction.\n\n11.10 _mysql_connector.MySQL.connect() Method\n\nSyntax:\n\n```python\nccnx.connect(args)\n```\n\nConnects to a MySQL server.\nimport _mysql_connector\n\nccnx = _mysql_connector.MySQL()\nccnx.connect(user='scott', password='password',\n host='127.0.0.1', database='employees')\nccnx.close()\n\nconnect() supports the following arguments: host, user, password, database, port,\nunix_socket, client_flags, ssl_ca, ssl_cert, ssl_key, ssl_verify_cert, compress.\nSee Section 7.1, \"Connector/Python Connection Arguments\".\n\nIf ccnx is already connected, connect() discards any pending result set and closes the connection\nbefore reopening it.\n\nRaises a TypeError exception if any argument is of an invalid type.\n\n11.11 _mysql_connector.MySQL.connected() Method\n\nSyntax:\n\nis_connected = ccnx.connected()\n\nReturns True or False to indicate whether the MySQL instance is connected.\n\n11.12 _mysql_connector.MySQL.consume_result() Method\n\nSyntax:\n\nccnx.consume_result()\n\nConsumes the stored result set, if there is one, for this MySQL instance, by fetching all rows. If the\nstatement that was executed returned multiple result sets, this method loops over and consumes all of\nthem.\n\n11.13 _mysql_connector.MySQL.convert_to_mysql() Method\n\nSyntax:\n\nconverted_obj = ccnx.convert_to_mysql(obj)\n\nConverts a Python object to a MySQL value based on the Python type of the object. The converted\nobject is escaped and quoted.\n\nccnx.query('SELECT CURRENT_USER(), 1 + 3, NOW()')\nrow = ccnx.fetch_row()\nfor col in row:\n print(ccnx.convert_to_mysql(col))\nccnx.consume_result()\n\nRaises a MySQLInterfaceError exception if the Python object cannot be converted.\n\n11.14 _mysql_connector.MySQL.escape_string() Method\n\nSyntax:\n\nstr = ccnx.escape_string(str_to_escape)\n\nUses the mysql_escape_string() C API function to create an SQL string that you can use in an\nSQL statement.\n\nRaises a TypeError exception if the value does not have a Unicode, bytes, or (for Python 2)\nstring type. Raises a MySQLError exception if the string could not be escaped.\n11.15 _mysql_connector.MySQL.fetch_fields() Method\n\nSyntax:\n\n```python\nfield_info = ccnx.fetch_fields()\n```\n\nFetches column information for the active result set. Returns a list of tuples, one tuple per column.\n\nRaises a `MySQLInterfaceError` exception for any MySQL error returned by the MySQL server.\n\n```python\nccnx.query('SELECT CURRENT_USER(), 1 + 3, NOW()')\nfield_info = ccnx.fetch_fields()\nfor fi in field_info:\n print(fi)\nccnx.consume_result()\n```\n\n11.16 _mysql_connector.MySQL.fetch_row() Method\n\nSyntax:\n\n```python\nrow = ccnx.fetch_row()\n```\n\nFetches the next row from the active result set. The row is returned as a tuple that contains the values converted to Python objects, unless `raw` was set.\n\n```python\nccnx.query('SELECT CURRENT_USER(), 1 + 3, NOW()')\nrow = ccnx.fetch_row()\nprint(row)\nccnx.free_result()\n```\n\nRaises a `MySQLInterfaceError` exception for any MySQL error returned by the MySQL server.\n\n11.17 _mysql_connector.MySQL.field_count() Method\n\nSyntax:\n\n```python\ncount = ccnx.field_count()\n```\n\nReturns the number of columns in the active result set.\n\n11.18 _mysql_connector.MySQL.free_result() Method\n\nSyntax:\n\n```python\nccnx.free_result()\n```\n\nFrees the stored result set, if there is one, for this MySQL instance. If the statement that was executed returned multiple result sets, this method loops over and consumes all of them.\n\n11.19 _mysql_connector.MySQL.get_character_set_info() Method\n\nSyntax:\n\n```python\ninfo = ccnx.get_character_set_info()\n```\n\nReturns information about the default character set for the current MySQL session. The returned dictionary has the keys `number`, `name`, `csname`, `comment`, `dir`, `mbminlen`, and `mbmaxlen`.\n\n11.20 _mysql_connector.MySQL.get_client_info() Method\n\nSyntax:\n\n```python\n```\n_mysql_connector.MySQL.get_client_version() Method\n\nSyntax:\n\n```python\ninfo = ccnx.get_client_info()\n```\n\nReturns the MySQL client library version as a string.\n\n11.21 _mysql_connector.MySQL.get_client_version() Method\n\nSyntax:\n\n```python\ninfo = ccnx.get_client_version()\n```\n\nReturns the MySQL client library version as a tuple.\n\n11.22 _mysql_connector.MySQL.get_host_info() Method\n\nSyntax:\n\n```python\ninfo = ccnx.get_host_info()\n```\n\nReturns a description of the type of connection in use as a string.\n\n11.23 _mysql_connector.MySQL.get_proto_info() Method\n\nSyntax:\n\n```python\ninfo = ccnx.get_proto_info()\n```\n\nReturns the protocol version used by the current session.\n\n11.24 _mysql_connector.MySQL.get_server_info() Method\n\nSyntax:\n\n```python\ninfo = ccnx.get_server_info()\n```\n\nReturns the MySQL server version as a string.\n\n11.25 _mysql_connector.MySQL.get_server_version() Method\n\nSyntax:\n\n```python\ninfo = ccnx.get_server_version()\n```\n\nReturns the MySQL server version as a tuple.\n\n11.26 _mysql_connector.MySQL.get_ssl_cipher() Method\n\nSyntax:\n\n```python\ninfo = ccnx.get_ssl_cipher()\n```\n\nReturns the SSL cipher used for the current session, or `None` if SSL is not in use.\n\n11.27 _mysql_connector.MySQL.hex_string() Method\n\nSyntax:\n\n```python\nstr = ccnx.hex_string(string_to_hexify)\n```\n\nEncodes a value in hexadecimal format and wraps it within `X'`. For example, \"ham\" becomes `X'68616D'`.\n11.28 _mysql_connector.MySQL.insert_id() Method\n\nSyntax:\n\n```python\ninsert_id = ccnx.insert_id()\n```\n\nReturns the AUTO_INCREMENT value generated by the most recent executed statement, or 0 if there is no such value.\n\n11.29 _mysql_connector.MySQL.more_results() Method\n\nSyntax:\n\n```python\nmore = ccnx.more_results()\n```\n\nReturns True or False to indicate whether any more result sets exist.\n\n11.30 _mysql_connector.MySQL.next_result() Method\n\nSyntax:\n\n```python\nccnx.next_result()\n```\n\nInitiates the next result set for a statement string that produced multiple result sets.\n\nRaises a MySQLInterfaceError exception for any MySQL error returned by the MySQL server.\n\n11.31 _mysql_connector.MySQL.num_fields() Method\n\nSyntax:\n\n```python\ncount = ccnx.num_fields()\n```\n\nReturns the number of columns in the active result set.\n\n11.32 _mysql_connector.MySQL.num_rows() Method\n\nSyntax:\n\n```python\ncount = ccnx.num_rows()\n```\n\nReturns the number of rows in the active result set.\n\nRaises a MySQLError exception if there is no result set.\n\n11.33 _mysql_connector.MySQL.ping() Method\n\nSyntax:\n\n```python\nalive = ccnx.ping()\n```\n\nReturns True or False to indicate whether the connection to the MySQL server is working.\n\n11.34 _mysql_connector.MySQL.query() Method\n\nSyntax:\n\n```python\nccnx.query(args)\n```\n\nExecutes an SQL statement. The permitted arguments are statement, buffered, raw, and raw_as_string.\nccnx.query('DROP TABLE IF EXISTS t')\ncnx.query('CREATE TABLE t (i INT NOT NULL AUTO_INCREMENT PRIMARY KEY)')\ncnx.query('INSERT INTO t (i) VALUES (NULL),(NULL),(NULL)')\nrow = cnx.fetch_row()\nprint('LAST_INSERT_ID(): ', row)\ncnx.consume_result()\n\nbuffered and raw, if not provided, take their values from the MySQL instance. raw_as_string is a special argument for Python v2 and returns str instead of bytearray (compatible with Connector/Python v1.x).\n\nTo check whether the query returns rows, check the have_result_set property of the MySQL instance.\n\nquery() returns True if the query executes, and raises an exception otherwise. It raises a TypeError exception if any argument has an invalid type, and a MySQLInterfaceError exception for any MySQL error returned by the MySQL server.\n\n11.35 _mysql_connector.MySQL.raw() Method\n\nSyntax:\n\n```python\nis_raw = cnx.raw() # getter\ncnx.raw(bool) # setter\n```\n\nWith no argument, returns True or False to indicate whether the MySQL instance return the rows as is (without conversion to Python objects).\n\nWith a boolean argument, sets the MySQL instance raw mode.\n\n11.36 _mysql_connector.MySQL.refresh() Method\n\nSyntax:\n\n```python\ncnx.refresh(flags)\n```\n\nFlushes or resets the tables and caches indicated by the argument. The only argument currently permitted is an integer.\n\nRaises a TypeError exception if the first argument is not an integer.\n\n11.37 _mysql_connector.MySQL.reset_connection() Method\n\nSyntax:\n\n```python\ncnx.reset_connection()\n```\n\nResets the user variables and session variables for a connection session.\n\n11.38 _mysql_connector.MySQL.rollback() Method\n\nSyntax:\n\n```python\ncnx.rollback()\n```\n\nRolls back the current transaction.\n\nRaises a MySQLInterfaceError exception on errors.\n\n11.39 _mysql_connector.MySQL.select_db() Method\n_mysql_connector.MySQL.set_character_set() Method\n\nSyntax:\n```python\ncnx.select_db(db_name)\n```\n\nSets the default (current) database for the current session.\n\nRaises a `MySQLInterfaceError` exception for any MySQL error returned by the MySQL server.\n\n**11.40 **_mysql_connector.MySQL.set_character_set() Method\n\nSyntax:\n```python\ncnx.set_character_set(charset_name)\n```\n\nSets the default character set for the current session. The only argument permitted is a string that contains the character set name.\n\nRaises a `TypeError` exception if the argument is not a `PyString_type`.\n\n**11.41 **_mysql_connector.MySQL.shutdown() Method\n\nSyntax:\n```python\ncnx.shutdown(flags)\n```\n\nShuts down the MySQL server. The only argument currently permitted is an integer that describes the shutdown type.\n\nRaises a `TypeError` exception if the first argument is not an integer. Raises a `MySQLErrorInterface` exception if an error is returned by the MySQL server.\n\n**11.42 **_mysql_connector.MySQL.stat() Method\n\nSyntax:\n```python\ninfo = cnx.stat()\n```\n\nReturns the server status as a string.\n\nRaises a `MySQLErrorInterface` exception if an error is returned by the MySQL server.\n\n**11.43 **_mysql_connector.MySQL.thread_id() Method\n\nSyntax:\n```python\nthread_id = cnx.thread_id()\n```\n\nReturns the current thread or connection ID.\n\n**11.44 **_mysql_connector.MySQL.use_unicode() Method\n\nSyntax:\n```python\nis_unicode = cnx.use_unicode() # getter\ncnx.use_unicode(bool) # setter\n```\n\nWith no argument, returns `True` or `False` to indicate whether the MySQL instance returns nonbinary strings as Unicode.\n\nWith a boolean argument, sets whether the MySQL instance returns nonbinary strings as Unicode.\n11.45 `_mysql_connector.MySQL.warning_count()` Method\n\nSyntax:\n\n```python\ncount = ccnx.warning_count()\n```\n\nReturns the number of errors, warnings, and notes produced by the previous SQL statement.\n\n11.46 `_mysql_connector.MySQL.have_result_set` Property\n\nSyntax:\n\n```python\nhas_rows = ccnx.have_result_set\n```\n\nAfter execution of the `query()` method, this property indicates whether the query returns rows.\nIndex\n\nSymbols\n\n_mysql_connector module, 78\n_mysql_connector.MySQL() class, 78\n_mysql_connector.MySQL.affected_rows() method, 78\n_mysql_connector.MySQL.autocommit() method, 78\n_mysql_connector.MySQL.buffered() method, 79\n_mysql_connector.MySQL.change_user() method, 79\n_mysql_connector.MySQL.character_set_name() method, 79\n_mysql_connector.MySQL.close() method, 79\n_mysql_connector.MySQL.commit() method, 79\n_mysql_connector.MySQL.connect() method, 79\n_mysql_connector.MySQL.connected() method, 80\n_mysql_connector.MySQL.consume_result() method, 80\n_mysql_connector.MySQL.convert_to_mysql() method, 80\n_mysql_connector.MySQL.escape_string() method, 80\n_mysql_connector.MySQL.fetch_fields() method, 81\n_mysql_connector.MySQL.fetch_row() method, 81\n_mysql_connector.MySQL.field_count() method, 81\n_mysql_connector.MySQL.free_result() method, 81\n_mysql_connector.MySQL.get_character_set_info() method, 81\n_mysql_connector.MySQL.get_client_info() method, 81\n_mysql_connector.MySQL.get_client_version() method, 82\n_mysql_connector.MySQL.get_host_info() method, 82\n_mysql_connector.MySQL.get_proto_info() method, 82\n_mysql_connector.MySQL.get_server_info() method, 82\n_mysql_connector.MySQL.get_server_version() method, 82\n_mysql_connector.MySQL.get_ssl_cipher() method, 82\n_mysql_connector.MySQL.have_result_set property, 86\n_mysql_connector.MySQL.hex_string() method, 82\n_mysql_connector.MySQL.insert_id() method, 83\n_mysql_connector.MySQL.more_results() method, 83\n_mysql_connector.MySQL.next_result() method, 83\n_mysql_connector.MySQL.num_fields() method, 83\n_mysql_connector.MySQL.num_rows() method, 83\n_mysql_connector.MySQL.ping() method, 83\n_mysql_connector.MySQL.query() method, 83\n_mysql_connector.MySQL.raw() method, 83\n_mysql_connector.MySQL.reset_connection() method, 84\n_mysql_connector.MySQL.rollback() method, 84\n_mysql_connector.MySQL.select_db() method, 84\n_mysql_connector.MySQL.set_character_set() method, 84\n_mysql_connector.MySQL.shutdown() method, 85\n_mysql_connector.MySQL.stat() method, 85\n_mysql_connector.MySQL.thread_id() method, 85\n_mysql_connector.MySQL.use_unicode() method, 85\n_mysql_connector.MySQL.warning_count() method, 86\n\nclass\n\nclass connection.MySQLConnection, 42\nconstants.CharacterSet, 70\nconstants.ClientFlag, 69\nconstants.FieldType, 69\nconstants.RefreshOption, 70\nconstants.SQLMode, 70\ncursor.MySQLCursor, 57\ncursor.MySQLCursorBuffered, 65\ncursor.MySQLCursorBufferedDict, 67\ncursor.MySQLCursorBufferedNamedTuple, 67\ncursor.MySQLCursorBufferedRaw, 66\ncursor.MySQLCursorDict, 66\ncursor.MySQLCursorNamedTuple, 67\ncursor.MySQLCursorPrepared, 68\ncursor.MySQLCursorRaw, 66\npooling.MySQLConnectionPool, 54\npooling.PooledMySQLConnection, 56\n_mysql_connector.MySQL(), 78\nCOM_STMT_SEND_LONG_DATA prepared statements, 69\nconnection.MySQLConnection class, 42\nconnection.MySQLConnection() constructor, 42\nConnector/Python, 1\nconstants.CharacterSet class, 70\nconstants.ClientFlag class, 69\nconstants.FieldType class, 69\nconstants.RefreshOption class, 70\nconstants.SQLMode class, 70\nconstructor\nconnection.MySQLConnection(), 42\ncursor.MySQLCursor, 57\npooling.MySQLConnectionPool, 54\npooling.PooledMySQLConnection, 56\ncursor.mysqlcursor\nSubclasses, 65\ncursor.MySQLCursor class, 57\ncursor.MySQLCursor constructor, 57\ncursor.MySQLCursorBuffered class, 65\ncursor.MySQLCursorBufferedDict class, 67\ncursor.MySQLCursorBufferedNamedTuple class, 67\ncursor.MySQLCursorBufferedRaw class, 66\ncursor.MySQLCursorDict class, 66\ncursor.MySQLCursorNamedTuple class, 67\ncursor.MySQLCursorPrepared class, 68\ncursor.MySQLCursorRaw class, 66\n\nd\n\nDYLD_LIBRARY_PATH environment variable, 33\n\nE\n\nenvironment variable\nDYLD_LIBRARY_PATH, 33\nerrorcode module, 71\nerrors.custom_error_exception() function, 74\nerrors.DatabaseError exception, 73\nerrors.DataError exception, 73\nerrors.Error exception, 72\nerrors.IntegrityError exception, 73\nerrors.InterfaceError exception, 73\nerrors.InternalError exception, 74\nerrors.NotSupportedError exception, 74\nerrors.OperationalError exception, 74\nerrors.PoolError exception, 74\nerrors.ProgrammingError exception, 74\nerrors.Warning exception, 74\nexception\nerrors.DatabaseError, 73\nerrors.DataError, 73\nerrors.Error, 72\nerrors.IntegrityError, 73\nerrors.InterfaceError, 73\nerrors.InternalError, 74\nerrors.NotSupportedError, 74\nerrors.OperationalError, 74\nerrors.PoolError, 74\nerrors.ProgrammingError, 74\nerrors.Warning, 74\n\nF\nfunction\nerrors.custom_error_exception(), 74\n\nM\nmethod\nmysql.connector.connect(), 41\nMySQLConnection.close(), 42\nMySQLConnection.cmd_change_user(), 44\nMySQLConnection.cmd_debug(), 45\nMySQLConnection.cmd_init_db(), 45\nMySQLConnection.cmd_ping(), 45\nMySQLConnection.cmd_process_info(), 45\nMySQLConnection.cmd_process_kill(), 45\nMySQLConnection.cmd_query(), 45\nMySQLConnection.cmd_query_iter(), 46\nMySQLConnection.cmd_quit(), 46\nMySQLConnection.cmd_refresh(), 46\nMySQLConnection.cmd_reset_connection(), 47\nMySQLConnection.cmd_shutdown(), 47\nMySQLConnection.cmd_statistics(), 47\nMySQLConnection.commit(), 43\nMySQLConnection.config(), 43\nMySQLConnection.connect(), 43\nMySQLConnection.cursor(), 44\nMySQLConnection.disconnect(), 47\nMySQLConnection.get_row(), 47\nMySQLConnection.get_rows(), 47\nMySQLConnection.get_server_info(), 48\nMySQLConnection.get_server_version(), 48\nMySQLConnection.issclientflag(), 48\nMySQLConnection.is_connected(), 48\nMySQLConnection.ping(), 48\nMySQLConnection.reconnect(), 48\nMySQLConnection.reset_session(), 49\nMySQLConnection.rollback(), 49\nMySQLConnection.set_charset_collation(), 49\nMySQLConnection.set_client_flag(), 50\nMySQLConnection.shutdown(), 50\nMySQLConnection.start_transaction(), 50\nMySQLConnectionPool.add_connection(), 54\nMySQLConnectionPool.get_connection(), 55\nMySQLConnectionPool.set_config(), 55\nMySQLCursor.add_attribute(), 58\nMySQLCursor.callproc(), 59\nMySQLCursor.clear_attributes(), 59\nMySQLCursor.close(), 60\nMySQLCursor.execute(), 60\nMySQLCursor.executemany(), 60\nMySQLCursor.fetchone(), 61\nMySQLCursor.fetchall(), 61\nMySQLCursor.fetchone(), 62\nMySQLCursor.fetchwarnings(), 62\nMySQLCursor.get_attributes(), 59\nMySQLCursor.stored_results(), 62\nPooledMySQLConnection.close(), 56\nPooledMySQLConnection.config(), 56\n_mysql.connector.MySQL.affected_rows(), 78\n_mysql.connector.MySQL.autocommit(), 78\n_mysql.connector.MySQL.buffered(), 79\n_mysql.connector.MySQL.change_user(), 79\n_mysql.connector.MySQL.character_set_name(), 79\n_mysql.connector.MySQL.close(), 79\n_mysql.connector.MySQL.commit(), 79\n_mysql.connector.MySQL.connected(), 80\n_mysql.connector.MySQL.consume_result(), 80\n_mysql.connector.MySQL.convert_to_mysql(), 80\n_mysql.connector.MySQL.escape_string(), 80\n_mysql.connector.MySQL.fetch_fields(), 81\n_mysql.connector.MySQL.fetch_row(), 81\n_mysql.connector.MySQL.field_count(), 81\n_mysql.connector.MySQL.free_result(), 81\n_mysql.connector.MySQL.get_character_set_info(), 81\n_mysql.connector.MySQL.get_client_info(), 81\n_mysql.connector.MySQL.get_client_info(), 81\n_mysql.connector.MySQL.get_client_version(), 82\n_mysql.connector.MySQL.get_host_info(), 82\n_mysql.connector.MySQL.get_proto_info(), 82\n_mysql.connector.MySQL.get_server_info(), 82\n_mysql.connector.MySQL.get_server_version(), 82\n_mysql.connector.MySQL.get_ssl_cipher(), 82\n_mysql.connector.MySQL.hex_string(), 82\n_mysql.connector.MySQL.insert_id(), 83\n_mysql.connector.MySQL.more_results(), 83\n_mysql.connector.MySQL.next_result(), 83\n_mysql.connector.MySQL.num_fields(), 83\n_mysql.connector.MySQL.num_rows(), 83\n_mysql.connector.MySQL.ping(), 83\nmysql.connector.MySQL.query(), 83\nmysql.connector.MySQL.raw(), 84\nmysql.connector.MySQL.refresh(), 84\nmysql.connector.MySQL.reset_connection(), 84\nmysql.connector.MySQL.rollback(), 84\nmysql.connector.MySQL.select_db(), 85\nmysql.connector.MySQL.set_character_set(), 85\nmysql.connector.MySQL.shutdown(), 85\nmysql.connector.MySQL.stat(), 85\nmysql.connector.MySQL.thread_id(), 85\nmysql.connector.MySQL.use_unicode(), 85\nmysql.connector.MySQL.warning_count(), 86\n\nModule\nerrorcode, 71\nmysql.connector, 41\nmysql.connector module, 41\nmysql.connector.apilevel property, 41\nmysql.connector.connect() method, 41\nmysql.connector.paramstyle property, 41\nmysql.connector.threadsafety property, 42\nmysql.connector.__version_info__ property, 42\nmysql.connector.__version__ property, 42\nMySQLConnection.autocommit property, 51\nMySQLConnection.can_consume_results property, 51\nMySQLConnection.charset property, 51\nMySQLConnection.close() method, 42\nMySQLConnection.cmd_change_user() method, 44\nMySQLConnection.cmd_debug() method, 45\nMySQLConnection.cmd_init_db() method, 45\nMySQLConnection.cmd_ping() method, 45\nMySQLConnection.cmd_process_info() method, 45\nMySQLConnection.cmd_process_kill() method, 45\nMySQLConnection.cmd_query() method, 45\nMySQLConnection.cmd_query_iter() method, 46\nMySQLConnection.cmd_quit() method, 46\nMySQLConnection.cmd_refresh() method, 46\nMySQLConnection.cmd_reset_connection() method, 47\nMySQLConnection.cmd_shutdown() method, 47\nMySQLConnection.cmd_statistics() method, 47\nMySQLConnection.commit() method, 43\nMySQLConnection.config() method, 43\nMySQLConnection.connect() method, 43\nMySQLConnection.connection_id property, 51\nMySQLConnection.cursor() method, 44\nMySQLConnection.database property, 52\nMySQLConnection.disconnect() method, 47\nMySQLConnection.get_row() method, 47\nMySQLConnection.get_rows() method, 47\nMySQLConnection.get_server_info() method, 48\nMySQLConnection.get_server_version() method, 48\nMySQLConnection.get_warnings property, 52\nMySQLConnection.is_connected() method, 48\nMySQLConnection.issecure() method, 48\nMySQLConnection.isset_client_flag() method, 48\nMySQLConnection.ping() method, 48\nMySQLConnection.raise_on_warnings property, 52\nMySQLConnection.reconnect() method, 48\nMySQLConnection.reset_session() method, 49\nMySQLConnection.rollback() method, 49\nMySQLConnection.server_host property, 53\nMySQLConnection.server_port property, 53\nMySQLConnection.set_charset_collation() method, 49\nMySQLConnection.set_client_flags() method, 50\nMySQLConnection.shutdown() method, 50\nMySQLConnection.sql_mode property, 53\nMySQLConnection.start_transaction() method, 50\nMySQLConnection.time_zone property, 53\nMySQLConnection.unix_socket property, 54\nMySQLConnection.unread_results property, 51\nMySQLConnection.user property, 54\nMySQLConnectionPool.add_connection() method, 54\nMySQLConnectionPool.get_connection() method, 55\nMySQLConnectionPool.pool_name property, 55\nMySQLConnectionPool.set_config() method, 55\nMySQLCursor.add_attribute() method, 58\nMySQLCursor.callproc() method, 59\nMySQLCursor.clear_attributes() method, 59\nMySQLCursor.close() method, 60\nMySQLCursor.column_names property, 63\nMySQLCursor.description property, 63\nMySQLCursor.execute() method, 60\nMySQLCursor.executemany() method, 61\nMySQLCursor.fetchall() method, 61\nMySQLCursor.fetchmany() method, 61\nMySQLCursor.fetchone() method, 62\nMySQLCursor.fetchwarnings() method, 62\nMySQLCursor.get_attributes() method, 62\nMySQLCursor.get_server_info() method, 62\nMySQLCursor.get_server_version() method, 62\nMySQLCursor.lastrowid property, 64\nMySQLCursor.rowcount property, 64\nMySQLCursor.statement property, 64\nMySQLConnectionPool.stored_results() method, 62\nMySQLCursor.stats() method, 65\nMySQLCursor.wait() method, 65\nMySQLCursor.with_rows property, 65\n\nP\nPEP 249, 1\nPooledMySQLConnection.close() method, 56\nPooledMySQLConnection.config() method, 56\nPooledMySQLConnection.pool_name property, 56\npooling.MySQLConnectionPool class, 54\npooling.MySQLConnectionPool constructor, 54\npooling.PooledMySQLConnection class, 55\npooling.PooledMySQLConnection constructor, 56\nprepared statements, 68\nproperty\nmysql.connector.apilevel, 41\nmysql.connector.paramstyle, 42\nmysql.connector.threadsafety, 42\nmysql.connector._version_info_, 42\nmysql.connector._version__, 42\nMySQLConnection.autocommit, 51\nMySQLConnection.can_consume_results, 51\nMySQLConnection.charset, 51\nMySQLConnection.collation, 51\n<table>\n<thead>\n<tr>\n<th>Attribute</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>MySQLConnection.connection_id</td>\n<td>51</td>\n</tr>\n<tr>\n<td>MySQLConnection.database</td>\n<td>52</td>\n</tr>\n<tr>\n<td>MySQLConnection.get_warnings</td>\n<td>52</td>\n</tr>\n<tr>\n<td>MySQLConnection.in_transaction</td>\n<td>52</td>\n</tr>\n<tr>\n<td>MySQLConnection.raise_on_warnings</td>\n<td>52</td>\n</tr>\n<tr>\n<td>MySQLConnection.server_host</td>\n<td>53</td>\n</tr>\n<tr>\n<td>MySQLConnection.server_port</td>\n<td>53</td>\n</tr>\n<tr>\n<td>MySQLConnection.sql_mode</td>\n<td>53</td>\n</tr>\n<tr>\n<td>MySQLConnection.time_zone</td>\n<td>53</td>\n</tr>\n<tr>\n<td>MySQLConnection.unix_socket</td>\n<td>54</td>\n</tr>\n<tr>\n<td>MySQLConnection.unread_results</td>\n<td>51</td>\n</tr>\n<tr>\n<td>MySQLConnection.user</td>\n<td>54</td>\n</tr>\n<tr>\n<td>MySQLConnectionPool.pool_name</td>\n<td>55</td>\n</tr>\n<tr>\n<td>MySQLCursor.column_names</td>\n<td>63</td>\n</tr>\n<tr>\n<td>MySQLCursor.description</td>\n<td>63</td>\n</tr>\n<tr>\n<td>MySQLCursor.lastrowid</td>\n<td>64</td>\n</tr>\n<tr>\n<td>MySQLCursor.rowcount</td>\n<td>64</td>\n</tr>\n<tr>\n<td>MySQLCursor.statement</td>\n<td>64</td>\n</tr>\n<tr>\n<td>MySQLCursor.with_rows</td>\n<td>65</td>\n</tr>\n<tr>\n<td>PooledMySQLConnection.pool_name</td>\n<td>56</td>\n</tr>\n<tr>\n<td>_mysql_connector.MySQL.have_result_set</td>\n<td>86</td>\n</tr>\n</tbody>\n</table>\n\nPython, 1\nPython Database API Specification v2.0 (PEP 249), 1\n\nS\n\nSubclasses cursor.mysqlcursor, 65"}}},{"rowIdx":56,"cells":{"id":{"kind":"string","value":"9f16a75c8b9fbdb350d82fa0971e16e3101bddcf"},"text":{"kind":"string","value":"Katello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nKatello 3.7 Installation\nThese instructions are for installing Katello 3.7, but the latest stable is 3.18.\n\nNote: After installation of Katello, be sure to trust Katello's CA certificate on your system. This is required for the encrypted NoVNC connections. You will find `katello-server-ca.crt` in the `/pub` directory of your Katello server (e.g. http://katello.example.com/pub/katello-server-ca.crt).\n\n**Important Note for Existing Installations**\n\nKatello does not currently support installation on existing Foreman deployments. **DO NOT attempt to install Katello on an existing Foreman deployment**, unless you are a Foreman developer and willing to debug the broken configuration that will result from attempting an install on existing system.\n\n**Hardware Requirements**\n\nKatello may be installed onto a baremetal host or on a virtual guest. The minimum requirements are:\n\n- Two Logical CPUs\n- 8 GB of memory (12 GB highly recommended)\n- The filesystem holding `/var/lib/pulp` needs to be large, but may vary depending on how many different Operating Systems you wish to synchronize:\n - Allocate 30 GB of space for each operating system. Even though an operating system may not take up this much space now, this allows space for future updates that will be synchronized later.\n- The path `/var/spool/squid` is used as a temporary location for some types of repository syncs and may grow to consume 10s of GB of space before the files are migrated to `/var/lib/pulp`. You may wish to put this on the same partition as `/var/lib/pulp`.\n- The filesystem holding `/var/lib/mongodb` needs at least 4 GB to install, but will vary depending on how many different Operating Systems you wish to synchronize:\n - Allocate around 40% of the capacity that has been given to the `/var/lib/pulp` filesystem\n- The root filesystem needs at least 20 GB of Disk Space\n\n**Required Ports**\n\nThe following ports need to be open to external connections:\n\n- 80 TCP - HTTP, used for provisioning purposes\n- 443 TCP - HTTPS, used for web access and api communication\n- 5647 TCP - qdrouterd - used for client and Smart Proxy actions\n- 9090 TCP - HTTPS - used for communication with the Smart Proxy\n\n**Production**\n\nKatello provides a puppet based installer for deploying production installations. Production installations are supported on the following OSes:\n\n<table>\n<thead>\n<tr>\n<th>OS</th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CentOS 7</td>\n<td>X</td>\n</tr>\n<tr>\n<td>RHEL 7</td>\n<td>X</td>\n</tr>\n</tbody>\n</table>\n\nKatello can only run on an x86_64 operating systems.\n\nInstallation may be done manually or via our recommended approach of using forklift.\n\n**Required Repositories**\n\nSelect your Operating System: [Red Hat Enterprise Linux 7]\n**Installation**\n\nAfter setting up the appropriate repositories, update your system:\n\n```\nyum -y update\n```\n\nThen install Katello:\n\n```\nyum -y install katello\n```\n\nAt this point the `foreman-installer` should be available to setup the server. The installation may be customized, to see a list of options:\n\n```\nforeman-installer --scenario katello --help\n```\n\n**Note**\n\nPrior to running the installer, the machine should be set up with a time service such as ntpd or chrony, since several Katello features will not function well if there is minor clock skew.\n\nThese may be set as command line options or in the answer file (/etc/foreman-installer/scenarios.d/katello-answers.yaml). Now run the options:\n\n```\nforeman-installer --scenario katello <options>\n```\n\n**Forklift**\n\nForeman provides a git repository designed to streamline setup by setting up all the proper repositories. Forklift provides the ability to deploy a virtual machine instance via Vagrant or direct deployment on an already provisioned machine. For details on how to install using forklift, please see the README.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nSmart Proxy Installation\nHardware Requirements\nThe Smart Proxy server is only supported on x86_64 Operating Systems\n\n- 2 Two Logical CPUs\n- 8 GB of memory\n- Disk space usage is similar to that of the main Katello server\n\nRequired Ports\nAt a minimum, the following ports need to be open to external connections for installation:\n\n- 80 TCP - HTTP, used for provisioning purposes\n- 443 TCP - HTTPS, used for web access and api communication\n- 9090 TCP - HTTPS - used for communication with the Smart Proxy\n\nSee the User Guide for additional information about Smart Proxy services and required ports.\n\nInstallation\nInstall needed packages:\nThe same yum repositories need to be configured on the Smart Proxy server as the main Katello server. See the installation guide for the list of required repositories.\n\nOnce you get the repositories configured, install the formean-proxy-content package on the Smart Proxy\n\n```\nyum install -y foreman-proxy-content python-django\n```\n\nGenerate Certificates for the Smart Proxies\nPrior to installing the Smart Proxy, we need to generate certificates on the main Katello server:\n\n```\nforeman-proxy-certs-generate --foreman-proxy-fqdn \"myproxy.example.com\"\n--certs-tar \"~/myproxy.example.com-certs.tar\"\n```\n\nIn the above example, replace ‘myproxy.example.com’ with your Smart Proxy's fully qualified domain name. This will generate a tar file containing all the needed certificates. You will need to transfer those certificates to the server that you will install your Smart Proxy on using whatever method you prefer (e.g. SCP).\n\nThe foreman-proxy-certs-generate command will output an example installation command. For example:\n\n```\nInstalling Success! [100%] [........................]\n\nTo finish the installation, follow these steps:\n\n1. Ensure that the foreman-installer-katello package is installed on the system.\n2. Copy ~/myproxy.example.com-certs.tar to the system myproxy.example.com\n3. Run the following commands on the Smart Proxy (possibly with the customized parameters, see foreman-installer --scenario formean-proxy-content --help and documentation for more info on setting up additional services):\n\n```\nyum -y localinstall http://katello.example.com/pub/katello-ca-consumer-latest.noarch.rpm\nsubscription-manager register --org \"Default_Organization\"\nforeman-installer --scenario formean-proxy-content\n --foreman-proxy-content-parent-fqdn \"katello.example.com\"\n --foreman-proxy-register-in-foreman \"true\"\n --foreman-proxy-base-url \"https://katello.example.com\"\n --foreman-proxy-trusted-hosts \"katello.example.com\"\n --foreman-proxy-trusted-hosts \"myproxy.example.com\"\n --foreman-proxy-consumer-key \"UVrAZfMaCfBiiWejoUVLYCZHT2xhuFV\"\n --foreman-proxy-consumer-secret \"ZH8p7M57tNU3WmUGWASag3JeXKgUX\"\n --foreman-proxy-oauth-consumer-key \"UVrAZfMaCfBiiWejoUVLYCZHT2xhuFV\"\n --foreman-proxy-oauth-consumer-secret \"ZH8p7M57tNU3WmUGWASag3JeXKgUX\"\n --foreman-proxy-content-certs-tar \"~/myproxy.example.com-certs.tar\"\n```\n\nThe full log is at /var/log/foreman-proxy-certs-generate.log\n\nInstall Smart Proxy\nUse the provide installation command from formean-proxy-certs-generate, and tailor for your own purposes as needed. The defaults will give you a Smart Proxy ready for Content-related services.\n\nSee the User Guide to learn about setting up provisioning related services, as well as the Foreman manual\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nClient Installation\nClient machines can be added in one of two ways: manually or via a provisioned host.\n\n**Manual**\n\nInstall the appropriate Katello client release packages. For CentOS 6, you will also need to enable the COPR repository for subscription-manager.\n\nSelect your Operating System: **Enterprise Linux 5 (CentOS, etc.)**\n\n```bash\nyum install -y http://fedorapeople.org/groups/katello/releases/yum/3.7/client/el5/x86_64/katello-client-repos-latest.rpm\n```\n\nNow you are ready to install the client package:\n\nThe **katello-host-tools** package reports errata & package profile information, but does not allow you to run remote actions on the clients.\n\n```bash\nyum install katello-host-tools\n```\n\nWe generally recommend using Foreman Remote Execution or Ansible for remote actions, but we also offer a messaging bus based client that does have some limitations when used with a large number of clients.\n\n```bash\nyum install katello-agent\n```\n\nOptionally you can also install **katello-host-tools-tracer** and the client will report processes that need restarting after an update back to the Katello server.\n\n```bash\nyum install katello-host-tools-tracer\n```\n\nFor Suse Clients, only katello-host-tools is supported:\n\n```bash\nzypper install katello-host-tools\n```\n\n**Provisioned**\n\nIn order to install the katello-agent package on a host you are provisioning, you will need to make the appropriate client repository available within your Katello. The first step is to either create a new product or add to an existing product, the appropriate client repository from the dropdown in the **manual** section above. After you create the new repositories, they will need to be synced locally. Next, you will then need to add them to the relevant content view(s) for the hosts you are wanting to provision. At this point, a new version of the content view can be published and promoted to the appropriate environments that you are wanting to provision a host into. At this point, you can go provision a host and the host will install the katello-agent package during setup.\n\nWhen provisioning new clients that should use Puppet 4, set a parameter called ‘enable-puppet4’ to ‘true’, so the templates know which package to install and where to place the configuration. This parameter can be placed at the host, host group, or another appropriate level of the hierarchy.\nKatello 3.7 supports upgrades from version 3.6 and Puppet version 4. For users transitioning from versions prior to 3.6, first upgrade to Katello 3.6, upgrade Puppet to version 4, and then proceed to upgrade to Katello 3.7 following the instructions below.\n\n**Pre-upgrade considerations**\n\nBefore you upgrade, you need to run the upgrade check script that will check for any active tasks, your version of Katello, and if there are any content hosts that will be deleted (see below).\n\nTo run the script:\n\n```\nforeman-rake katello:upgrade_check\n```\n\n**Step 1 - Backup**\n\nIf Katello is running on a Virtual Machine, we recommend to take a snapshot prior to upgrading. Otherwise, take a backup of the relevant databases by following the instructions here.\n\n**Step 2 - Operating System**\n\nEnsure your operating system is fully up-to-date:\n\n```\nyum -y update\n```\n\n**NOTE:** If kernel packages are updated here (e.g. upgrading el 6.6 to 6.7), you must reboot and ensure the new kernel and SELinux policy is loaded before upgrading Katello.\n\n**Step 3 - Repositories**\n\nUpdate the Foreman and Katello release packages:\n\n- RHEL7 / CentOS 7:\n\n ```\nyum update -y http://fedorapeople.org/groups/katello/releases/yum/3.7/katello/el7/x86_64/katello-repos-latest.rpm\n yum update -y http://yum.theforeman.org/releases/1.18/el7/x86_64/foreman-release.rpm\n yum update -y foreman-release-scl\n ```\n\n**Step 4 - Update Packages**\n\nStop the Katello services\n\n```\nkatello-service stop\n```\n\nClean the yum cache\n\n```\nyum clean all\n```\n\nUpdate the required packages:\n\n```\nyum -y update\n```\n\n**Step 5 - Run Installer**\n\nThe installer with the --upgrade flag will run the right database migrations for all component services, as well as adjusting the configuration to reflect what's new in Katello 3.7\n\n```\nforeman-installer --scenario katello --upgrade\n```\n\nCongratulations! You have now successfully upgraded your Katello to 3.7 For a rundown of what was added, please see the release notes.\n\nIf for any reason, the above steps failed, please review /var/log/foreman-installer/katello.log – if any of the “Upgrade step” tasks failed, you may try to run them manually below to aid in troubleshooting.\nForeman 2.3.3 has been released! Follow the quick start to install it.\n\nForeman 2.2.2 has been released! Follow the quick start to install it.\nSmart Proxy Upgrade\nStep 1 - Operating System\n\nEnsure your operating system is fully up-to-date:\n\n```\nyum -y update\n```\n\n**NOTE:** If kernel packages are updated here (e.g. upgrading el 6.6 to 6.7), you must reboot and ensure the new kernel and SELinux policy is loaded before upgrading Katello.\n\nStep 2 - Repositories\n\nUpdate the Foreman and Katello release packages:\n\n- RHEL7 / CentOS 7:\n\n```\nyum update -y http://fedorapeople.org/groups/katello/releases/yum/3.7/katello/el7/x86_64/katello-repos-latest.rpm\nyum update -y http://yum.theforeman.org/releases/1.18/el7/x86_64/foreman-release.rpm\n```\n\nStep 3 - Update Packages\n\nClean the yum cache\n\n```\nyum clean all\n```\n\nUpdate packages:\n\n```\nyum update -y\n```\n\n```\nyum install foreman-proxy-content\n```\n\nStep 4 - Regenerate Certificates\n\nOn the Katello server, regenerate the certificates tarball for your Smart Proxy:\n\n```\nforeman-proxy-certs-generate --foreman-proxy-fqdn \"myproxy.example.com\" --certs-update-all --certs-tar \"~/myproxy.example.com-certs.tar\"\n```\n\nAnd copy them to your Smart Proxy:\n\n```\nscp ~/myproxy.example.com-certs.tar myproxy.example.com:\n```\n\nStep 5 - Run Installer\n\nThe installer with the --upgrade flag will run the right database migrations for all component services, as well as adjusting the configuration to reflect what’s new in Katello 3.7\n\n```\nforeman-installer --scenario foreman-proxy-content --upgrade --foreman-proxy-content-certs-tar ~/myproxy.example.com-certs.tar --certs-update-all --certs-regenerate true --certs-deploy true\n```\n\nCongratulations! You have now successfully upgraded your Smart Proxy to 3.7. For a rundown of what was added, please see release notes.\n\nIf for any reason, the above steps failed, please review /var/log/foreman-installer/foreman-proxy.log – if any of the “Upgrade step” tasks failed, you may try to run them manually below to aid in troubleshooting.\nForeman 2.3.3 has been released! Follow the quick start to install it.\n\nForeman 2.2.2 has been released! Follow the quick start to install it.\n\nView our Privacy Policy\n\nThis web site is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License. Source available: github/theforeman/theforeman.org\n\nThanks to our sponsors for hosting this website and our project services.\nClient Upgrade\nWhen upgrading clients there are 2 scenarios: manually added clients and provisioned clients.\n\n**Step 1 - Update Repositories**\n\n**Manually Added Clients**\n\nUpdate the Katello client release packages:\n\nSelect your Operating System: [Enterprise Linux 5 (RHEL, CentOS, etc.)]\n\n```\nyum update -y http://fedorapeople.org/groups/katello/releases/yum/3.7/client/el5/x86_64/katello-client-repos-latest.rpm\n```\n\n**Provisioned Clients**\n\nIf the katello-agent was setup during provisioning from a locally synced repository then you will need to go through some **initial setup** to add the 3.7 client repositories to your Katello for each version needed. After you create the new repositories, they will then need to be added to the relevant content view(s) and the older versions removed. At this point, a new version of the content view can be published and promoted to the appropriate environments. Once the new package is available the clients can be updated following the next steps.\n\n**Step 2: Update Packages**\n\nClean the yum cache\n\n```\nyum clean all\n```\n\nUpdate packages:\n\n```\nyum update katello-agent\n```\n\n---\n\n**Foreman 2.3.3 has been released!** Follow the quick start to install it.\n\n**Foreman 2.2.2 has been released!** Follow the quick start to install it.\n\n---\n\nView our Privacy Policy\n\nThis web site is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License. Source available: [github/theforeman/theforeman.org](https://github/theforeman/theforeman.org)\n\nThanks to our sponsors for hosting this website and our project services.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nKatello 3.7 (Blonde Ale) Release Notes\nFor the full release notes, see the Changelog.\n\nFeatures\n\nNew Red Hat Repositories & Subscriptions Pages\nCompletely redesigned with an eye toward usability and functionality.\n\nNew Upstream Subscriptions API\nFor users with Red Hat content we now provide an API for managing subscriptions against existing manifests. Check the API documentation for details.\n\nContent Views\nComposite content views can be configured to auto-publish when one of its components is changed.\n\nClient Tooling\nZypper and DNF plugins have been added to support errata applicability similar to Yum clients\n\nBackup and Restore Utilities\nWe are beginning to adopt Foreman Maintain for Katello. Our first endeavor has been to utilize it for backup and restore capabilities.\n\nThe primary goals of this change are to:\n\n- Centralize system operations in a single tool\n- Support remote databases\n- Support new Mongo versions (3.4)\n\n*katello-backup* and *katello-restore* are completely removed so please be sure to update any cron jobs or scripts using them.\n\nContributors\n\n- agrawal\n- Adam Ruzicka\n- Andrew Kofink\n- Bernhard Suttner\n- Bryan Kearney\n- Chris Duryee\n- Chris Hale\n- Christine Fouant\n- Daniel Lobato Garcia\n- Dan Seethaler\n- Dmitri Dolguikh\n- Eric D. Helms\n- Evgeni Golov\n- Ido Kanner\n- Ivan Nečas\n- John Mitsch\n- Jonathon Turel\n- Justin Sherrill\n- kgaikwad\n- Idjebran\n- Lukas Zapletal\n- Marek Hulan\n- Masatake YAMATO\n- Matthias Dellweg\n- Michael Johnson\n- Michael Moll\n- Ondrej Prazak\n- Partha Aji\n- Paul Donohue\n- Quirin Pamp\n- Ranjan Kumar\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\nWhat is the CLI?\n\nThe Hammer CLI provides users with a command-line interface for interacting with Katello. It's our goal to make all functionality that's accessible through Katello's Web UI also available through Hammer so that users may use Hammer for their entire Katello workflow.\n\nInstallation\n\nThe first step to install the CLI is to setup the appropriate repositories: foreman, katello and epel.\n\nSelect your Operating System: Red Hat Enterprise Linux 6\n\n```\nyum -y --disablerepo=* --enablerepo=rhel-6-server-rpms install yum-utils wget\nyum-config-manager --disable ***\nyum-config-manager --enable rhel-6-server-rpms epel\nyum-config-manager --enable rhel-6-server-optional-rpms\n```\n\nAfter setting up the appropriate repositories, install Katello:\n\n```\nyum -y install tfm-rubygem-hammer_cli_katello\n```\n\nHow do I use Hammer?\n\nTo get started with hammer, view the help:\n\n```\nhammer -u <user> -p <password> --help\n```\n\nHow do I contribute to Hammer?\n\nSee the Katello Hammer CLI project if you want to get setup for contributing to the hammer code.\n\n---\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\n\n---\n\nView our Privacy Policy\n\nThis web site is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License. Source available: github/theforeman/theforeman.org\n\nThanks to our sponsors for hosting this website and our project services.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. API Documentation\n8. Annotated Backend Requests\n\nActivation Keys\nActivation Keys provide a mechanism to define properties that may be applied to Content Hosts during registration. This includes properties such as:\n\n- Lifecycle Environment\n- Content View\n- Subscriptions\n- Repository Enablement\n- Host Collections\n\nDefinitions\n\n- **Content Host**\n- Host Collection - A statically defined group of Content Hosts.\n- **Subscription** - The right to receive the associated content from Katello.\n\nGeneral Features\n\nThe following is a high-level summary of the Activation Key features:\n\n- Create an Activation Key\n- Add subscriptions to an Activation Key\n- Change repository enablement for an Activation Key\n- Add Host Collections to an Activation Key\n- Register a Content Host using an Activation Key\n\nCreate an Activation Key\n\nTo create a new key,\n\n- navigate to: Content > Activation Keys\n- click **New Activation Key**\n\n- **Name**: This required option is used to identify the activation key to command line tools, such as `subscription-manager`.\n\n- **Content Host Limit**: This option will control how many Content Hosts may be registered using the key. An “unlimited” value will not place any limits on usage. Specifying a quantity will limit the number of registered content hosts.\nRegistering with an activation key consumes one of the available limit quantity, while unregistering makes it available again. (i.e. this quantity is not a usage counter but a limit of actively registered content hosts)\n\n- **Description:** A free form text field that can be used to store a description of the key for later reference or for pseudo-tagging that can be used to search.\n- **Environment** and **Content View:** Although optional, at least one activation key used during registration must specify a content view. Activation keys are used in the order specified to `subscription-manager` meaning the last activation key with a content view takes precedence.\n\nThe following example would use CV_B's content view:\n\n```\nsubscription-manager register --org Default_Organization --activationkey NO_CV --activationkey CV_A --activationkey CV_B\n```\n\nOr equivalently:\n\n```\nsubscription-manager register --org Default_Organization --activationkey NO_CV,CV_A,CV_B\n```\n\nFor registration to succeed, at least one activation key must be successfully applied. For an activation key to succeed, at least one of the listed subscriptions must be successfully attached to the registering content host.\n\n### Add Subscriptions to an Activation Key\n\nTo add subscriptions to a key:\n\n- navigate to: Content > Activation Keys\n- select the desired key from the list\n- click **Subscriptions**\n- click **Add**\n- select the Subscriptions you would like to add\n- click **Add Selected**\n\nThe **Auto-Attach** setting controls how the group of subscriptions are processed during registration.\n\nWhen 'Auto-Attach' is enabled but no subscriptions are added to the activation key, subscriptions will be automatically added to cover the installed products. This is equivalent to passing the `--auto-attach` flag to the `subscription-manager` command:\n\n```\nsubscription-manager register --org=Default_Organization --auto-attach\n```\n\nWhen 'Auto-Attach' is enabled and subscriptions are listed for the activation key, two things will happen. First all subscriptions for custom products will be attached to the registering content host. Second, the group of Red Hat subscriptions will be attached as needed to cover the content host's installed Red Hat products. This is most commonly used when there is a group of similar subscriptions (e.g. several Red Hat Enterprise Linux from different contracts, or guest subscriptions from different hypervisors) and which one used is not important. Katello's subscription tooling, **Candlepin**, will automatically choose the minimal proper subscriptions from the group.\n\nFinally, when 'Auto-Attach' is disabled, all subscriptions on the activation key will attached to the registering content host, regardless of whether needed to cover an installed product or not. For example, adding an OpenStack Platform subscription would then allow that product to be installed after registration.\nTo change repository enablement settings using a key:\n\n- **navigate to**: Content > Activation Keys\n- **select** the desired key from the list\n- **click** Product Content\n- **click** the edit icon for the repository content set that you would like to modify\n- **select** the desired value (e.g. 'Override to Yes', 'Override to No', 'Defaults to Yes', 'Defaults to No')\n- **click** Save\n\n**View current settings:**\nChange current settings:\n\nAdd Host Collections to an Activation Key\nTo add Host Collections to a key:\n\n- navigate to: Content > Activation Keys\n- select the desired key from the list\n- click Host Collections\n- click Add\n- select the Host Collections you would like to add\n- click Add Selected\n\nRegister a Content Host using an Activation Key\n\nThe simplest form of registering a content host with an activation key is this:\n\n```\nsubscription-manager register --org=Default_Organization --activationkey=$KEY_NAME\n```\n\nClick here for more information\n\nNote that modifying an activation key does not change anything on content hosts previously registered with the key.\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\n\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nBackup\nPlease use Foreman Maintain for backup and restore functionality. Foreman-maintain is a dependency of Katello starting in 3.7.\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. API Documentation\n8. Annotated Backend Requests\n\nSmart Proxies\nWhat are Smart Proxies?\n\nThe Smart Proxy server is a Katello component that provides federated services to discover, provision, control, and configure hosts. Each Katello server includes a Default Smart Proxy, and you may deploy additional Smart Proxies to remote data centers. A Smart Proxy server provides the following features:\n\n- Content features, including:\n - Repository synchronization\n - Content delivery\n - Host action delivery (package installation updates, etc)\n - Subscription management proxy (RHSM)\n- Foreman Smart Proxy features, including:\n - DHCP, including ISC DHCP servers\n - DNS, including Bind and MS DNS servers\n - Realm, including FreeIPA\n - Any UNIX-based TFTP server\n - Puppet Master servers\n - Puppet CA to manage certificate signing and cleaning\n - Baseboard Management Controller (BMC) for power management\n - Provisioning template proxy\n\nThe Katello Smart Proxy server is a means to scale out the Katello installation. Organizations can create various Smart Proxies in different geographical locations. These are centrally managed through the Katello server. When a Katello user promotes content to a particular environment, the Katello server will push the content to each of the Smart Proxy servers subscribed to that environment. Hosts pull content and configuration from the Katello Smart Proxy servers in their location and not from the central server.\n\nIn a fully configured Smart Proxy, communication is completely isolated between hosts and the Katello server.\n\nWhat is a Foreman Proxy with Content?\n\nA Katello Smart Proxy is a Foreman Smart Proxy with the addition of content-related services.\n\nDeployment\n\nIn the simplest use case, a user may only want to use the Default Smart Proxy. Larger deployments would have a single Katello server with multiple Smart Proxies attached, with these remote Smart Proxies deployed to various datacenters. Smart Proxies can also be used to scale the number of hosts attached to a single Katello server.\n\nInstallation\n\nSee Smart Proxy Installation\n\nRemoval\n\nTo stop all services and remove all Katello and Foreman related packages, run the following command as root on the Smart Proxy:\n\n```\nkatello-remove\n```\n\nSmart Proxy Isolation\n\nThe goal of Smart Proxy Isolation is to provide a single endpoint for all of a client’s communication, so that in remote network segments, you need only open Firewall ports to the Smart Proxy itself. The following section details the communication clients need to have with a Smart Proxy. The installation options mentioned are the default starting with Katello 2.2.\nContent and Configuration Services\n\nThere are five primary areas that require client communication:\n\n1 - Content Delivery\n\nThat is, yum. Katello Smart Proxies by default have the Pulp feature, which mirrors content for the selected Lifecycle Environments.\n\nInstall Option:\n\n- `--pulp=true`\n\nRequired Connectivity:\n\n- Clients need to be able to communicate with the Smart Proxy on port 443/tcp.\n2 - Katello Agent\n\nThe Katello agent is a goferd plugin which allows you to schedule remote actions on hosts such as package installation, updates, etc. A Smart Proxy must be running the Qpid Dispatch Router service for this feature to work.\n\nInstall Option:\n- `--qpid-router=true`\n\nRequired Connectivity:\n- Clients need to be able to communicate with the Smart Proxy on port 5647/tcp\n\n3 - Puppet & Puppet CA\n\nBy default, the Puppet CA feature on the Smart Proxy is an independent CA which will manage the certificates for all the clients registered against the Smart Proxy. Simply select the Puppetmaster and Puppet CA to be the Smart Proxy when creating a host.\n\nInstall Option:\n- `--puppet=true` `--puppetca=true`\n\nRequired Connectivity:\n- Clients need to communicate with the Smart Proxy on port 8140/tcp\n\n4 - Subscription Management\n\nContent Hosts utilize Subscription Manager for registration to Katello and enabling/disabling specific repositories.\n\nInstall Option:\n- `--reverse-proxy=true`\n\nRequired Connectivity:\n- Clients need to talk to the Smart Proxy on port 8443/tcp\n\n5 - Provisioning Services\n\nWhen provisioning a host using DHCP/PXE, you will need, at a minimum, the TFTP feature enabled on the Smart Proxy, and a DHCP server available. While not required, the Smart Proxy can provide the DHCP service. In order for the installer to obtain its kickstart template from the Smart Proxy, you should enable the templates feature.\n\nIf a TFTP proxy has the Templates feature as well, Foreman will automatically make the communication isolated. Your clients need to talk to the Smart Proxy on port 67/udp and 68/udp for DHCP, 69/udp for TFTP, and 8000/tcp for Templates.\n\nConsult the installer’s `--help` for the full range of provisioning options.\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\n\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nContent\nKatello can currently host two different types of content, RPMs and puppet modules. RPMs and Puppet Modules can be synced from an external resource or can be uploaded directly.\n\nThe advantages to using Katello to mirror your local content are:\n\n- Reduce bandwidth usage and increase download speed by having client machines pull updates from Katello\n- Provision hosts using local Repositories covered HERE TODO\n- Customize content locally, covered HERE TODO\n\nDefinitions\n\n- Repository - Collection of content (either RPM or puppet)\n- Product - Collection of Repositories, Content Hosts subscribe to a product\n- Library - A special pre-created Lifecycle Environment where Repositories are created and content is synced or uploaded to. A Content Host can subscribe to library and receive content as soon as the content is synced or uploaded.\n\nCreating a Product\n\nFrom the web UI, navigate to:\n\nContent > Products > New Product (top right)\n\nCreating a Repository\n\nFrom the web UI, navigate to:\n\nContent > Products > Select desired product > Create Repository (right hand side)\n\nNote the following options:\n\n- Publish via HTTP: allows access to the Repository without any restriction. Unless you desire to restrict access to your content in this Repository, we recommended to leave this checked.\n- URL: If you are syncing from an external Repository (yum or puppet), this would be filled in. This can be changed, added, or removed later. For example if you are wanting to create a mirror of EPEL, you would set this to 'http://dl.fedoraproject.org/pub/epel/6/x86_64/.'\nSyncing a Repository\n\nFrom the web UI, navigate to:\n\nContent > Products > Select desired product > Select the Repository > Sync Now\nThe progress will be displayed:\n\nSyncing multiple repositories\nTo easily sync multiple repositories at once and track their progress, navigate to:\n\nContent > Sync Status\n\nFrom here you can expand the desired products, and select multiple repositories to sync.\n\nUploading RPM Content\n\nUploading RPM content directly is not currently supported. You will need to build a custom yum Repository. TODO Provide instructions on creating a custom yum repo\n\nUploading Puppet Content\n\nTo upload puppet modules, first create a Repository with type puppet (similarly to creating a yum Repository above):\nWhen creating this Repository the URL field can be left blank.\n\nPuppet modules can be uploaded via the Web UI, navigate to:\n\nContent > Repositories > Products > Select desired Product > Select desired Puppet Repository > Select file on the right\nSubscribing a System to a Product for yum content\nTo read about registering systems and subscribing them to the Product click TODO.\n\nScheduling Repository Synchronization\nSync plans give you the ability to schedule Repository synchronization on a hourly, daily or weekly basis. Sync Plans are applied to Products and thus all Repositories within a Product will be synchronized according to the products plan.\n\nCreating a Sync Plan\nIf you would like to schedule certain repositories to sync on a hourly, daily or weekly basis, Sync Plans give you this capability.\nTo create a Sync Plan, navigate to:\nContent > Sync Plans > click “New Sync Plan” on the upper right\nThe Start Date and Start Time fields are used as the day of the week/month and time of the day to run the re-occuring syncs.\nFor example a sync plan that starts on Sunday 2014-04-06 at 2:30 will occur every Sunday at 2:30 every week if it has a weekly interval. If on a daily interval it would sync every day at 2:30.\n\nAssigning a Sync Plan to a Product\nNavigate to:\nContent > Sync Plans > Select your Sync Plan > Products > Add\nThen select the Products you want to add and click “Add Selected” in the upper right.\nGPG Keys\n\nTo learn about securing your packages and Repositories with GPG Keys click here. TODO\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\n\nView our Privacy Policy\n\nThis web site is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License. Source available: github/theforeman/theforeman.org\n\nThanks to our sponsors for hosting this website and our project services.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nContent Hosts\nWhat is a Host?\nA Host is a Foreman concept that represents a server/host/system/computer (whatever you want to call it). In addition to holding facts about the system, it:\n\n- Stores which operating system the system should be running\n- Stores which puppet classes should be assigned\n- Stores which parameters apply to which puppet classes\n- Allows you to re-provision the machine\n\nWhat are Content Hosts?\nContent Hosts are the part of a host that manages Content and Subscription related tasks. As time goes on more and more of this functionality will be moved to the Host object. A Host's Content Host:\n\n- Stores which Products are assigned (i.e. which Repositories will the system pull content from)\n- Initiates package install/upgrade/removal\n- Determines which errata apply to a system\n- Initiates errata installation\n\nHow is a Content Host registered?\nSubscription Manager is the client for Katello that handles registration.\n\nInstalling Subscription Manager\nDepending on your Operating System, for:\n\n- RHEL, subscription-manager is installed by default\n- Fedora, subscription-manager is available from the Everything repo for its release: `yum install subscription-manager`\n- CentOS 7, subscription-manager is available in the ‘os’ repo for its release: `yum install subscription-manager`\n- CentOS 5/6, enable the upstream subscription-manager repo and then install subscription-manager (be sure to change ‘6’ to ‘5’ if you're on ELS, as the version from 6 will not work):\n\n```\nyum install subscription-manager -y\n```\n\nRegistering with Subscription Manager\nFirst install the bootstrap rpm from your Katello server:\n\n```\nrpm -Uvh http://$KATELLO_HOSTNAME/pub/katello-ca-consumer-latest.noarch.rpm\n```\n\nThen register:\n\n```\nsubscription-manager register --org=Default_Organization --environment=Library\n```\n\nSubscription manager will prompt for your username and password. You can also specify `--username $USER --password $PASS` on the command line.\n\nRegistering to a Content View\nTo register to Content View “MyView” in a “Devel” Lifecycle Environment:\n\n```\nsubscription-manager register --org=Default_Organization --environment=Devel/MyView\n```\n\nRegistering without using a username and password\nActivation Keys allow you to register and consume content without using a username and password. To create an Activation Key see the Activation Key Guide\n\nOnce you have created an activation key, register with:\n\n```\nsubscription-manager register --org=Default_Organization --activationkey=$KEY_NAME\n```\nActions with registered Content Hosts\nTo see the list of your Content Hosts, navigate to Hosts > Content Hosts\n\nChanging the Lifecycle Environment and Content View of a Content Host:\nNavigate to the Content Host Details page, Host > Content Hosts > Click the name of the desired Content Host\nLook in the upper right corner for the “Content Host Content”:\nThen select the new Lifecycle Environment you desire, select the new Content View you desire, and click save.\n\nAssigning a Content Host to a Product\nIn order for a Content Host to receive package updates and access Repositories hosted on Katello, it needs to be subscribed to a product.\nNavigate to Hosts > Content Hosts > Select Content Host > Subscriptions > Click the “Add” tab\nCheck the checkbox under the Products you want to add and select “Add Selected” in the upper right.\nTo see existing attached Products, click the “List/Remove” tab. To remove a Product, select the checkbox under the desired Product in this list and click “Remove Selected”.\n\nPackage Management\nTo perform package actions on a single Content Host, navigate to: Hosts > Content Hosts > Select Content Host > Packages\nFrom here you can:\n- See a list of installed packages\n- Perform a yum install/update/remove of a Package or Package Group\n- Update all packages (equivalent of running ‘yum update’)\n\nView and Install Applicable Errata\nIf your synced Repositories contain Errata, you can use Katello’s Errata management to track and install Errata.\nNavigate to: Hosts > Content Hosts > Select Content Host > Errata\nTo apply errata, search for the errata you want and select the checkbox beside each errata. Then click “Apply Selected” at the top right.\nThe “Show From” filters what applicable errata to show:\n- Current Environment - Shows only Applicable Errata available in the Host’s Content View & Lifecycle Environment.\n- Previous Environment - Shows Applicable Errata that are available from the Host’s Content View but in the previous Lifecycle Environment. Promoting the Content View Version from that previous Lifecycle Environment to the current Lifecycle Environment for this Host would cause all Applicable Errata shown to then be available.\n- Library Synced Content - Shows Applicable Errata which have been synced to the Library. This shows you what is applicable even when the Errata have not been published into a Content View. All applicable Errata are shown regardless of availability to the Content Host.\nChange Host Collection Assignments\n\nTo change Host Collection assignments for a Content Host, navigate to: Hosts > Content Hosts > Select Content Host > Host Collections\n\nBulk Actions\n\nKatello provides the ability to perform actions on many Content Hosts at once such as:\n\n- Package installation/upgrade/removal\n- Listing and applying applicable errata\n- Assigning Host Collections\n- Changing Lifecycle Environment and Content View assignments\n\nIn order to use the bulk actions, perform whatever search you desire and select which Content Hosts you want to modify. If you want to select all Content Hosts from a search result, click the ‘checkbox’ above the table:\n\nThis will select all Content Hosts on that page (only the ones that are visible). To select all that correspond to that search query, notice a bar has now appeared:\n\nNext select the ‘Bulk Actions’ button in the top right.\n\nFrom here you can select the tab corresponding to any action you wish to perform.\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\nWhat can a Content View be used for?\n\n- To stage content through environments (Dev, Test, Production).\n- To filter the contents of a repository (include a package or exclude certain errata, for example).\n- To have multiple snapshots of the same repository and/or puppet modules.\n\nDefinitions\n\n- Content View - snapshot of one or more repositories and/or puppet modules.\n- Composite Content View - a Content View that contains a collection of other Content Views.\n- Filter - provides finer grained control over content in a Content View. Can be used to include or exclude specific packages, package groups, or errata.\n- Publishing - Content Views are 'published' in order to lock their contents in place. The content of the Content View is cloned and all filters applied. Publishing creates a new version of the Content View.\n- Promoting - Content Views can be cloned to different Lifecycle Environments (Dev, Test, Production).\n\nGeneral Workflow\n\nFirst create a product and repository in the library environment and populate the repository with content (by syncing it or uploading content). A Content Host can now register directly to library and be attached to the content therein. Updates will be available as soon as new content is synced or uploaded.\n\nTo utilize Content Views for filtering and snapshotting:\n\n1. Create a Content View\n2. Add the desired repository and/or puppet modules to the Content View\n3. Optionally create one or more Filters to fine tune the content of the Content View.\n4. Publish the Content View\n5. Attach the Content Host to the Content View\n6. Optionally promote the Content View to another environment\n\nAt this point the Content Host will no longer be getting content directly from Library, but from the Content View. Updates to library will not affect this Content Host.\n\nNote that all of the actions below can also done with hammer, the CLI tool, and examples are given at the end of each section.\n\nCreating a Content View\n\nTo create a Content View using the web UI, navigate to:\n\nContent > Content Views\n\nClick the Create New View button on the top right of the screen.\nCreating a Composite Content View\n\nTo create a Composite Content View using the web UI follow the above steps for Creating a Content View but check the “Composite View?” checkbox.\n\nFrom the CLI:\n\n```\nhammer content-view create\n --organization=\"Default Organization\"\n --name=\"New Composite Content View\"\n --description=\"This is my new composite content view.\"\n```\n\nAdding Repositories\n\nAdding a repository to a Content View means whenever a Content View is published, all of the content contained within the repository at that time is included in the Content View. If the repository is synced after publishing the Content View, the Content View will contain the state of the repository prior to syncing. A new version of the Content View must be published in order for the new version to get the contents of the newly synced repository.\n\nTo add a repository using the web UI, navigate to:\n\nContent > Content Views > Select the desired Content View > Content (within sub navigation) > Repositories\n\nFrom the CLI, adding a repository:\n\n```\nhammer content-view add-repository\n --organization=\"Default Organization\"\n --name=\"New Content View\"\n --repository=\"CentOS 6.5\"\n```\n\nAdding a Puppet Module\n\nAdding a puppet module to a Content View means that whenever the Content View is published the puppet module is locked to the version selected. If the “Use Latest” version is selected then the puppet module will be “frozen” at the latest version available when the Content View is published. A new version of the Content View must be published in order for the new\nversion to get any updated puppet module.\n\nTo add a puppet module using the web UI, navigate to:\n\nContent > Content Views > Select the desired Content View > Puppet Modules (within sub navigation)\nFrom the CLI, first find the UUID of your puppet module from the list:\n\n```bash\nhammer puppet-module list --organization=\"Default Organization\" --repository \"Puppet Modules\"\n```\n\nThen add the puppet module:\n\n```bash\nhammer content-view puppet-module add --organization=\"Default Organization\" --uuid=91cc9bb7-dbb3-4798-b50a-45173b763cbb\n```\n\n**Adding Content Views to a Composite Content View**\n\nAdding a version of a Content View to a Composite Content View means whenever the Composite Content View is published, all of the content contained within the specific version of that Content View is contained in the Composite Content View. If the Content Views contained within the Composite Content View are updated (i.e. a new version is published) or if their content is\nupdated after publishing the Composite Content View, the Composite Content View will only contain the versions of the Content View(s) prior to syncing. A new version of the Composite Content View must be published in order for it to get the updated Content Views.\n\nTo add a Content View to a Composite Content View using the web UI, navigate to:\n\nContent > Content Views > Select the desired Content View > Content (within sub navigation) > Repositories\n\nFind the Content View ID of the specific version of the Content View to add:\n\n```\nhammer content-view version list \\\n --organization=\"Default Organization\" \\\n --content-view=\"New Content View\"\n```\n\nFrom the CLI, add a Content View to a composite Content View:\n\n```\nhammer content-view update \\\n --organization=\"Default Organization\" \\\n --content-view=\"New Composite Content View\" \\\n --component-ids=2\n```\n\nCreating a filter\n\nIf only using Content Views as snapshots, Filters are unnecessary. If the desire is to filter what content make it into the view, such as blacklisting a package by name or version, or blacklisting errata by date or type, Filters can help accomplish these tasks.\n\nTo create a new Content View Filter using the web UI, navigate to:\n\nContent > Content Views > Select the desired Content View > Content (within sub navigation) > Filters > New Filter\nFrom the CLI, adding a Content View Filter:\n\n```\nhammer content-view filter create \\\\\n --organization=\"Default Organization\" \\\\\n --content-view=\"New Content View\" \\\\\n --name=\"New Filter\" \\\\\n --inclusion=false \\\\\n --type=rpm\n```\n\nFrom the CLI, adding a Content View Filter rule:\n\n```\nhammer content-view filter rule create \\\\\n --organization=\"Default Organization\" \\\\\n --content-view=\"New Content View\" \\\\\n --content-view-filter=\"New Filter\" \\\\\n --name=\"something-else\" \\\\\n --max-version=\"10.0.0\" \\\\\n --min-version=\"10.0.0\"\n```\n\nSelecting whichRepositories to Filter\nBy default a Filter applies to all repositories (present and future) in the Content View. It's possible to select which repositories within the Content View apply to the filter. This is useful, for example, if the desire is to exclude errata from only certain repositories in a view.\n\nTo select which repositories to Filter in the web UI, navigate to:\n\nContent > Content Views > Select the desired Content View > Content (within sub navigation) > Filters > Select the desired Filter > Affected repositories (within sub navigation)\n\nFrom the CLI, adding a Content View Filter:\n\n```\nhammer content-view filter update \\\n --organization=\"Default Organization\" \\\n --name=\"New Filter\" \\\n --repository-ids=2,3,7\n```\n\nPublishing a Content View\n\nPublishing a Content View produces a new version of the content view that is subsequently promoted to the Library lifecycle environment. This newly published version of the content view is now available to any content host registered to Library.\n\nTo publish a Content View, in the web UI, navigate to:\n\nContent > Content Views > Select the desired Content View > Publish New Version\nFrom the CLI:\n\n```\nhammer content-view publish\n --organization=\"Default Organization\" \\\n --name=\"New Content View\"\n```\n\nRegistering a Content Host\n\nTo register a Content Host that is not currently registered to the Content View, simply use subscription manager on the client Content Host and run:\n\n```\nsubscription-manager register --org=ACME_Corporation --environment=Library/my_rhel_view\n```\n\nThis would register the Content Host to the Library environment and the my_rhel_view Content View.\n\nIf the Content Host is already registered, from the UI:\n\nHosts > Content Hosts > Select the desired Content Host\n\nFrom the CLI:\n\n```\nhammer content-host update \\\n --organization=\"Default Organization\" \\\n --name=\"dhcp129-211.rdu.redhat.com\" \\\n --content-view=\"New Content View\" \\\n --lifecycle-environment=\"Library\"\n```\n\nPromoting a Content View\n\nInitially a Content View is published to Library as version 1. If there are Content Hosts in other environments that would like to consume this Content View, a version of the content view will need to be promoted to those environments. For example, given the Content View “New Content View”, version 1 of which has been promoted to the Dev environment. Any Content Hosts in Dev attached to the Content View would remain at version 1 until a version 2 is both published and promoted to the Dev environment.\n\nTo promote a Content View in the Web UI, navigate to:\n\nContent > Content Views > Select the desired Content View > Versions (within sub navigation) > Click promote for desired version\nNew Content View\n\nVersion | Status | Environments | Content | Author\n---|---|---|---|---\nVersion 1 | Published | Library | 487 Packages | 112 Errors | 44 | 305\n\nPromote Version 1\n\nChoose one or more lifecycle environments from the existing promotion paths available in \"Library\".\nTo promote a Content View in the CLI:\n\n```\nhammer content-view version promote\n --organization=\"Default Organization\" \\\n --content-view=\"New Content View\" \\\n --to-lifecycle-environment=\"Test\" \\\n --version 1\n```\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nKatello Inter-Server Sync\nNOTE: This feature is intended to replace the 'katello-disconnected' script.\n\nIntro\n\nIf you are working in an air-gapped network environment where some of your Katello servers do not have Internet connectivity, you may be interested in using the Katello Inter-Server Sync (ISS) feature. This allows you to export repos, including repos in content views, on your “upstream” Katello server, and then import said repos into your “downstream” server that does not have connectivity. Individual repos can be exported, or all of the repos in a content view.\n\nList of currently supported repo content types:\n\n- yum\n\nFuture releases will enable support for additional content types.\n\nThe diagram above shows an example scenario where a user wants to export all Yum content in a content view and then import to another Katello server. The ISO file is burned to media and then walked across the air-gap in the network.\n\nDetailed Operation\n\nExporting\n\nThe ISS feature allows users to move Yum content from one Katello server to another, in a way that is compatible with air-\ngapped networks. Typically users will set up an upstream server that is connected to the Internet, and then create a content view that contains Yum content that they would like to present to the downstream server (step 1).\n\nContent is exported via either hammer repository export or hammer content-view version export (step 2). It is exported to the location set in “pulp_export_destination” in the Settings page, under the Katello tab. This defaults to /var/lib/pulp/katello_export. Please be aware that the location needs to be readable and writable by the foreman user. SELinux permissions also need to be set on the export location with the type httpd_sys_rw_content_t as well as foreman user and group ownership.\n\nYou can select to either export as a plain set of directories, or as a set of ISO files. The “iso_size_mb” parameter sets how large you would like each ISO file to be. It defaults to 4380 MB, which is the size of a single-side, single-layer DVD.\n\nImporting\n\nImporting (step 3) can be done in one of two ways. The first way is to make the export available via HTTP to the importing Katello instance. Simply put the export in /var/www/html/pub/export, either via copy or symlink. After that, edit your CDN location from the manifest import page to point to “http://export/path/to/export” and the Red Hat Repos page will then work as expected, using your exported data. Please be sure to use 'http' and not 'https' when altering the CDN url. Katello by default only supports the CA certificate for `cdn.redhat.com`. This is a [known limitation](http://projects.theforeman.org/issues/16392) that will be addressed in a future version.\n\nThe second way is to perform a repository sync via hammer, specifying the source location. Please see the hammer repository sync command for more information. This method is the only way to import custom content, and is the only way to import incremental content.\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nDocker Management\nKatello can be used to manage and deploy Docker content. Katello can retrieve Docker content from a variety of sources such as Docker hub, private Docker registries, the Red Hat CDN, and so forth. Docker content can then be published and promoted via Content Views and then pulled or provisioned to a server running Docker.\n\nWhat is Docker?\nDocker is a tool used to manage Linux containers. To read more about Docker, check out the official Docker site. Docker repositories, which contain images and tags, can be retrieved, stored, managed, and deployed from Katello.\n\nHow to sync a Docker repository\nThe easiest way to get Docker content into Katello is to sync it in. You can either sync Docker content from the Red Hat CDN (if you have subscriptions for the content) or from a registry such as Docker Hub.\n\nRed Hat Docker Images\nContent can be synced into Katello using a Red Hat manifest in much the same way as yum content. See our guide on how to manage Red Hat content for more information.\n\nDocker Hub/Docker Registry\nTo sync content from a Docker registry such as Docker Hub (which is the official Docker-run registry), simply start by creating a new Repository.\n\nOn the new Repository screen, select “Docker” as the content type. Once you do that, you'll be given two options: upstream name and URL. The URL will be the registry URL; for Docker Hub, this would be https://registry.hub.docker.com.\n\nFor the upstream name, you want to use the fully qualified upstream name which also includes any namespace such as the username. This can be just “busybox” if the Repository is an official Docker Hub Repository or it can be something like “fedora/ssh” where “fedora” is the username/namespace.\n\nThen click save and then sync the Repository as you normally would. Katello will fetch all the images and tags contained within that Repository.\n\nHow to Upload Docker Images\nIn versions of Katello prior to 3.0, Docker images could be uploaded directly via either the UI or CLI. However, Katello 3.0 only supports the Docker Registry v2 format, which is significantly different than the Docker Registry v1 format. The docker save command outputs a Docker image in v1 format, which cannot be uploaded directly to a v2 repository.\n\nAs a workaround, you can create a local Docker registry like so:\n\ndocker run -p 5030:5000 --name registry registry:2\n\nNote the :2 above, which specifies a v2 registry. Push your changes to your newly created local registry then follow the instructions in the section above to sync this registry to Katello. This will ensure that your Docker content stays in Docker's v2 registry format.\n\nHow to Publish and Promote Docker Content\nDocker content can be published and promoted via Content Views much like yum or puppet content.\n\nAfter creating a Content View, visit the Docker Content tab. Here you can select any Docker repositories you want to add to your Content View. After you've added Docker Repositories to your view, you may proceed as normal. Visit the Content View user guide for more information.\n\nHow to View and Pull Docker Content\nTo view Docker content contained with Katello, visit the Docker Tags page. This can be accessed under the Content menu at the top of any page.\nOn the Docker Tags page, you can see a list of Docker Tags grouped by Repository in Katello. This shows you Tags grouped across Content Views and Lifecycle Environments. Suppose I wanted to pull the latest Tag from my redis repository, I would click the latest row for my redis repository.\n\nI can see here that my redis Repository has been added to a published Content View called redisv. If I want to use the tag from that Content View, I would just copy the Published At URL and then on my docker server I would run:\n\n```bash\n$ docker pull localhost:5000/default_organization-library-redisv-Tester-redis:latest\nPulling repository localhost:5000/default_organization-library-redisv-Tester-redis...\n```\n\n### How to Provision Docker Content\n\nSee how to provision content in the documentation in the [foreman-docker documentation](https://theforeman.org/docs/). Provisioning content from Katello works in much the same way.\n\nFirst, proceed to the new Container page by accessing it from the Containers menu at the top. Then, select the Local Content tab on the second step. This will allow you to select a Docker image from a published Katello repository which is in an environment/content view/Smart Proxy. Then just proceed in the wizard as per the Foreman Docker instructions. When you are finished, you should have a new container running from an image in Katello.\nEmail Notifications\nTypes of Email Notifications\n\nIn addition to the Email Notifications that Foreman provides:\n\n- Puppet run summary (Daily/Weekly/Monthly)\n- Puppet errors\n\nKatello provides a few addition reports:\n\n- Katello Host Advisory (Daily/Weekly/Monthly) - A report of all of the Errata applicable to all readable Content Hosts\n- Katello Promote Errata - A report generated at Content View promotion time showing what Errata applicable to the Content Hosts within that Content View.\n- Katello Sync Errata - A report generated after each Repository sync listing new Errata synced and how many Content Hosts are applicable.\n\nConfiguring the Foreman/Katello to send emails:\n\nThe configuration of how the Foreman/Katello service sends email is located in Administer > Settings > Email.\n\nFor more information see: Email Configuration\n\nOpting in to the emails\n\nBy default a user will receive no email notifications. Each notification must be opted into.\n\nTo opt in for your own user, at the very top right of the web interface, hover over your Username, click “My Account” and then click the “Mail Preferences” tab.\n\nTo opt in for other users, navigate to “Administer” > “Users” > Click the desired User > click the “Mail Preferences” tab.\n\nSelect which emails and frequency you would like the user to have and click “Submit”.\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nErrata\nErrata are updates between major releases. An Erratum is metadata about a group of packages that explains the importance of the package updates. Errata may be released individually on an as-needed basis or aggregated as a minor release. There are three main types of errata:\n\n- **Enhancement**: the new packages contain one or more added features\n- **Bugfix**: the new packages contain one or more bug fixes\n- **Security**: the new packages fix one or more security vulnerabilities\n\nWith regard to Content Hosts, Errata is divided into two distinct classifications depending on whether or not the Erratum is present in the Content Host's Lifecycle Environment and Content View:\n\n- **Applicable**: the errata applies to one or more Content Hosts\n- **Installable**: the errata applies to one or more Content Hosts and is present in the Content Host's Lifecycle Environment and Content View\n\n**Definitions**\n\n- **Content Host**\n- **Content View**\n- **Lifecycle Environment**\n\n**General Features**\n\nThe following is a high-level summary of the Errata features:\n\n- **View List of Errata**\n- **View Errata Details**\n- **View Affected Content Hosts**\n- **View Repositories Containing Errata**\n- **Applying Errata**\n\n**View List of Errata**\n\nTo view the list of Errata in the Organization:\n\n- navigate to: Content > Errata\n\n**View Errata Details**\n\nTo view the details of an Errata:\nView Affected Content Hosts\n\nTo view the Affected Content Hosts of an Errata:\n\n- navigate to: Content > Errata\n- Click on an Errata ID\n- Click on the Content Hosts Tab\n\nNote the following option:\n\n- Checking the box limits the display of Content Hosts to those which already have the Errata available in their Lifecycle Environment and Content View.\nView Repositories Containing Errata\n\nTo view the Repositories Containing an Errata:\n\n- navigate to: Content > Errata\n- Click on an Errata ID\n- Click on the Repositories Tab\n\nNote that you can filter by Lifecycle Environment and Content View.\nApplying Errata\n\nHow Errata is applied to a Content Host(s) depends on whether the Errata is installable.\n\n- If the Errata is already installable then the Errata is applied to the Content Host(s).\n- If the Errata is not installable then an Incremental Update is generated. An Incremental Update creates a point release of the Content View with the Errata included. The Errata can also be applied to the Content Host(s) as part of this process.\n\nThere are two ways to apply Errata:\n\n- A single Errata can be applied to one or more Content Hosts\n- Several Errata can be applied to one or more Content Hosts via a bulk operation\n\nApplying a Single Errata\n\nTo apply a single Errata:\n\n- Navigate to: Content > Errata\n- Click on an Errata ID\n- Click on the Content Host tab\n- Select the desired Content Hosts\n- Click “Apply to Hosts”\n- Confirm the action\nApplying Several Errata\n\nTo apply several Errata:\n\n- Navigate to: Content > Errata\n- Select the desired Errata\n- Click “Apply Errata”\n- Select the intended Content Hosts\n- Click “Next”\n- Confirm the action\nForeman 2.3.3 has been released! Follow the quick start to install it.\n\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nContent Credentials\nContent Credentials can be associated with Katello Products and Repositories. Two types of Content Credentials are supported, each having a distinct purpose:\n\nGPG Keys\nGPG Keys are used by Content Hosts in order to verify the signature of packages that have been retrieved from a Repository and ensure they haven't been corrupted. For more information on GPG Keys see The GNU Privacy Guard.\n\nSSL Certificates\nSSL Certificates are used by the Katello server to sync content from upstream repositories that require client SSL authentication.\n\nUsing Content Credentials\n- Create a Content Credential\n- Associate Content Credential with a Product\n- View Associated Products\n- View Associated Repositories\n\nCreate a Content Credential\nTo create a new Content Credential:\n- navigate to Content > Content Credentials\n- click Create Content Credential\n- Enter a Name and select a Type\n- You may either upload your Credential or paste its content into the text area.\n\nWhen creating SSL Certificates for Products or Repositories that require them, a separate credential must be created for the CA, cert, and key respectively.\n\nAssociate Content Credential with a Product\nTo add a Content Credential to a Product:\nNote that adding a Credential to a Product adds it to all current and future repositories unless a repository already has a Credential assigned. The Credential currently assigned to a Repository can be modified or overridden from the detail view of the repository.\n- navigate to Content > Products\n- select the desired Product from the list\n- click **Details**\n- click the edit icon on the GPG Key, SSL CA Cert, SSL Client Cert, or SSL Client Key field\n- select the desired Content Credential\n\nThe steps for adding a Credential to a Repository are the same but performed from the repository’s detail view.\n\n---\n\n**View Associated Products**\n\nTo view all Products that have been assigned a Content Credential:\n\n- navigate to Content > Content Credentials\n- select the desired Credential from the list\n- click **Products**\n\n---\n\n**View Associated Repositories**\n\nTo view all Repositories that have been assigned a Content Credential:\n\n- navigate to Content > Content Credentials\n• select the desired Credential from the list\n• click Repositories\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nManaging Content Hosts using Host Collections\nHost Collections provide a mechanism to statically group multiple Content Hosts. This enables administrators to group Content Hosts based on the needs of their organization. For example, Content Hosts could be grouped by function, department or business unit.\n\nOnce a Host Collection is created, it can be used to perform various actions on the Content Hosts contained within it. This includes actions such as the following:\n\n- Package installation, removal and update\n- Errata installation\n- Changing of assigned Lifecycle Environment or Content View\n\nDefinitions\n\n- Content Host\n\nGeneral Features\n\nThe following is a high-level summary of the Host Collection features:\n\n- Create a Host Collection\n- Add Content Hosts to a Host Collection\n- Copy a Host Collection\n- Perform actions on a Host Collection\n\nCreate a Host Collection\n\nTo create a new collection,\n\n- navigate to: Hosts > Host Collections\n- click New Host Collection\n\nNote the following option:\n\n- Content Host Limit: This option will control how many Content Hosts are allowed to be added to the collection.\n\nAdd Content Hosts to a Host Collection\nTo add Content Hosts to a collection:\n\n- navigate to: Hosts > Host Collections\n- select the desired collection from the list\n- click **Content Hosts**\n- click **Add**\n- select the Content Hosts you would like to add\n- click **Add Selected**\n\nCopy a Host Collection\n\nCopying a Host Collection allows a user to quickly create a new collection that is a copy of an existing one.\n\nTo copy a Host Collection:\n\n- navigate to: Hosts > Host Collections\n- select the desired collection from the list\n- click **Copy Collection**\n- enter a name for the new collection\n- click **Create**\nPerform Actions on a Host Collection\n\nTo perform an action on Content Hosts within a collection:\n\n- navigate to: Hosts > Host Collections\n- select the desired collection from the list\n- click **Collection Actions**\n- click on the action that you would like to perform\n### Hosts\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Details</th>\n<th>Content Hosts</th>\n<th>Collection Actions</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>development</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>research</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nThe following actions can be performed on content hosts in this host collection:\n\n- Package Installation, Removal, and Update\n- Errata Installation\n- Host Collection Membership\n- Change assigned Environment or Content View\n\nNote: clicking on an action will take the user to the appropriate Content Hosts Bulk Actions page, where all Content Hosts associated with the collection have been selected. Click here, for more information on performing Content Host Bulk Actions.\n\n---\n\n**Foreman 2.3.3 has been released!** Follow the quick start to install it.\n\n**Foreman 2.2.2 has been released!** Follow the quick start to install it.\n\n---\n\nView our [Privacy Policy](#).\n\nThis web site is licensed under a [Creative Commons Attribution-ShareAlike 3.0 Unported License](https://creativecommons.org/licenses/by-sa/3.0/). Source available: [github/theforeman/theforeman.org](https://github/theforeman/theforeman.org).\n\nThanks to our sponsors for hosting this website and our project services.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nLifecycle Environments\nWhat can a Lifecycle Environments be used for?\n\n- Hold content view versions.\n- To manage the lifecycle of Content Hosts.\n- Establish workflow containers and promote content views.\n\nDefinitions\n\n- Lifecycle Environment - containers for content view versions which are consumed by content hosts.\n- Library - a special kind of Lifecycle Environment that does not have a parent. The library serves as the main container for synced content such as products, puppet modules, and published content views. Every organization has a library. Subsequent environments are derived from the library. The first node of an environment is the Library, all future environments are derived from the library and follow the library in promotion order.\n- Lifecycle Environment Path - Sequence of lifecycle environments that form the content promotion order.\n\nGeneral Workflow\n\nFirst create a lifecycle environment connected to the library life cycle environment and promote content views to the new lifecycle environment. A Content Host can now register directly to the promoted content view in the promoted environment or library therein. Updates will be available as soon as new content is synced and promoted.\n\nViewing the list of lifecycle environments\n\nFrom the web UI, navigate to:\n\nContent -> Lifecycle Environments\n\nCreating a lifecycle environment\n\nClick on the + next to the Library or the prior environment to add a new path\nCreating a lifecycle environment path\n\nClick on the New Environment Path\nView/Updating environment name\nClick on the name of the environment.\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nProvisioning\nSee the Foreman manual for general information on configuring provisioning.\n\nTemplates\nKatello ships a number of templates in addition to the standard Foreman ones. When using these templates, if a host has a Host group with an Activation Key, it will register as a Content Host automatically.\n\n- **Katello Kickstart Default** - Kickstart template for Fedora, CentOS, RHEL, and other Red Hat-compatible operating systems.\n- **Katello Kickstart Default Finish** - image-based provisioning\n- **Katello Kickstart Default User Data** - cloud-init template for EC2 and OpenStack\n- **subscription_manager_registration** - Snippet for registering a host for content\n\nTo customize any of the above templates, simply clone them and add your changes.\n\nWhen you synchronize a repository with a distribution such as Fedora or CentOS, Katello will automatically create the operating system and assign these default templates. You may change the defaults by going to Administer > Settings, and selecting the Katello tab.\nManaging Puppet Content\nImporting the Puppet Forge\n\nThe Puppet Forge is a collection of puppet modules written by the community which can be used to manage hosts in Katello. These modules can be used in content views as described in the content views guide in order to configure the running hosts.\n\nTo import the puppet forge navigate to\n\nContent > Products\n\nClick on the +New Product button.\n\nOnce the product is created, select the product and click the Create Repository button. Fill out the repository as shown:\n\nThis can be done via the CLI:\n\n```\nhammer product create\n--organization \"Default Organization\"\n--name Puppet\n\nhammer repository create\n--organization \"Default Organization\"\n--product Puppet\n--name forge\n--content-type puppet\n--url \"https://forge.puppetlabs.com/\n\n```\n\nThe repository can now be synced.\n\nImporting Puppet Modules from Git\n\nIn order to allow users to import puppet modules from Git repositories, Katello comes with a tool called 'pulp-puppet-module-builder' from the pulp-puppet-tools RPM. This utility will be available on the Katello server but it can also be installed on another machine if desired. By running the 'pulp-puppet-module-builder' against a Git repository, it will checkout the repository, build all of the modules, and publish them in a structure Katello can synchronize.\n\nThe most common method is to run the utility on the Katello server itself and publish to a local file system directory and sync against that directory.\n\n```\nmkdir /modules\nchmod 755 /modules\n\npulp-puppet-module-builder --output-dir=/modules --url=\"git@mygitserver.com:mymodules.git\" --branch=develop\n```\n\nThis will checkout the 'develop' branch of the Git repository located at 'git@mygitserver.com:mymodules.git' and publish them\nto the `/modules` directory. If you have SELinux enabled, in order to sync from the file system, you'll need to apply a label to the files in order for the system to access them. Two options are `httpd_sys_r_content_t` or `pulp_tmp_t`. Note: if you choose `httpd_sys_r_content_t` then the webserver can also read the files so that may or may not be good. One way to apply these labels would be to use the `chcon` command.\n\nNext, from within Katello, simply set the url on your Puppet Repository to `file://modules`. You can now sync the Repository just like any other Repository.\n\nIf you are running this on a remote machine, you will need to publish the containing to folder to a location accessible by HTTP or HTTPS.\n\n```\nmkdir /var/www/html/modules/\nchmod 755 /var/www/html/modules/\npulp-puppet-module-builder --output-dir=/var/www/html/modules --url=git@mygitserver.com:mymodules.git --branch=develop\n```\n\nThen in Katello, simply enter `http://HOSTNAME/modules/` for the Repository url and sync it like you normally would.\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nRed Hat Content\nKatello can be used to manage content associated with Red Hat products based upon available subscriptions. This includes content such as RPMs, package groups, errata and distributions.\n\nDefinitions\n\n- Subscription Manifest - An archive file containing certificates and data that represent the subscriptions that are available. A subscription manifest is created and downloaded from the Red Hat Customer Portal.\n- Repository - Collection of content (either rpm or puppet).\n- Product - Collection of repositories (content hosts attach to a product).\n- Library - The initial lifecycle environment where repositories are created. Content that is synced or uploaded lands in the library.\n\nGeneral Workflow\n\nThe following is a high-level summary of the workflow:\n\n- Create a subscription manifest using the Red Hat Customer Portal\n- Import the subscription manifest\n- Enable Red Hat repositories\n- Synchronize repositories\n- Schedule repository synchronization\n- Attach a content host to a product for Red Hat content\n\nCreate a Subscription Manifest Using the Red Hat Customer Portal\n\nIf you are a Red Hat customer, you should have access to the Red Hat Customer Portal to create and download a subscription manifest. Once created, the manifest can be imported into a Katello Organization.\n\nTo access the Red Hat Customer Portal, click here\n\nFor details on how to create a subscription manifest, click here\n\nImport the Subscription Manifest\n\nImporting a subscription manifest will allow for Red Hat content associated with purchased subscriptions to be enabled and synchronized to Katello.\n\nTo import a manifest,\n\n- navigate to: Content > Red Hat Subscriptions\n- click Choose File\n- navigate to the file containing the manifest (e.g. manifest.zip)\n- click Open\n- click Upload\nEnable Red Hat Repositories\n\nOnce a subscription manifest is imported, access is available to potentially hundreds of Red Hat Repositories (e.g. Red Hat Enterprise Linux Server, Red Hat Enterprise Virtualization...etc). This process allows you to select only those that you are interested in for your enterprise.\n\nTo enable Red Hat repositories,\n\n- navigate to: Content > Red Hat Repositories\n- select the content type: RPMs, Source RPMs, Debug RPMs, Beta, ISOs or Other\n- select one or more Red Hat products (e.g. Red Hat Enterprise Linux Server)\n- select one or more Repository Sets (e.g. Red Hat Enterprise Linux 6 Server (RPMs))\n- select one or more Repositories (e.g. Red Hat Enterprise Linux 6 Server RPMs x86_64 6Server)\n\nNote:\n\n- When enabling a RHEL repository, Red Hat recommends selecting the Server repo (e.g. 6Server, 5Server) versus a specific release (e.g. 6.2). When a specific release is necessary, the preferred way is to create a Content View with filters that narrow the content to the desired version (e.g. 6.2)\n- If you plan to provision content hosts, be sure to enable both the RPM and Kickstart repositories.\nExpand each Red Hat Product below to examine the different repository sets available. When enabling a repository set, the different repositories within are discovered and may be enabled individually.\n\n### Enable Red Hat Repositories\n\n<table>\n<thead>\n<tr>\n<th>PRODUCT</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Red Hat Enterprise Linux High Availability for RHEL Server</td>\n</tr>\n<tr>\n<td>Red Hat Enterprise Linux Load Balancer for RHEL Server</td>\n</tr>\n<tr>\n<td>Red Hat Enterprise Linux Resilient Storage for RHEL Server</td>\n</tr>\n<tr>\n<td>Red Hat Enterprise Linux Server</td>\n</tr>\n<tr>\n<td>Red Hat Enterprise Linux Workstation</td>\n</tr>\n</tbody>\n</table>\nSynchronize Repositories\n\nSynchronizing a repository will retrieve all associated content and mirror the content in the Katello Library lifecycle environment.\n\nTo sync multiple repositories as well as track their progress,\n\n- navigate to: Content > Sync Status\n- expand the desired products\n- select the repositories to sync\n- click Synchronize Now\nCreating a Sync Plan\n\nSync plans provide the ability to schedule repository synchronization on a daily, weekly or a monthly basis. Sync plans can be applied individually or to a set of repositories.\n\nTo create a Sync Plan:\n\n- navigate to: Content > Sync Plans\n- click New Sync Plan on the upper right\n\nNote the following options:\n\n- **Start Date** and **Start Time**: specify the day of the week/month and time of the day to run the recurring syncs. For example, a sync plan that starts on Sunday 2014-04-06 at 2:30 will occur every Sunday at 2:30 every week if it has a weekly interval. If on a monthly interval it would sync every month on the 6th day at 2:30.\nAssigning a Sync Plan to a Red Hat Product\n\nTo assign a sync plan to a product,\n\n- navigate to Content > Sync Plans\n- select your Sync Plan\n- click Products\n- click Add\n- select the products that you want to add\n- click Add Selected on the upper right\nAttach a Content Host to a Product for Red Hat Content\n\nTo read about registering a content host and subscribing it to a product, click TODO.\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello can be used to manage content associated with SUSE products based upon contents mirrored via the smt tool. This includes content such as RPMs, errata.\n\nDefinitions\n- Repository - Collection of content (either rpm).\n- Product - Collection of repositories (content hosts attach to a product).\n- Library - The initial lifecycle environment where repositories are created. Content that is synced or uploaded lands in the library.\n\nGeneral Workflow\nThe following is a high-level summary of the workflow:\n- Set up SUSE account and smt server\n- Set up the smt mirroring and Content\n- Create Products and Repositories\n\nSet up SUSE account and SMT server\nAssuming you have an SCC account, setup the SMT server, [click here](#) for more documentation.\n\n- Install smt\n\n```\n# zypper install smt\n# yast smt-server\n```\n\n- A TUI will pop up and you are going to have to [add credentials from your account](#), found in scc.suse.com, as shown in screenshot below\n\n\n\n- Click ok and proceed with the steps provided, it will finish up and exit\n\nSet up the SMT Content and mirroring\nOn a SLES 12 Box\n\n- Sync repo data\n\n```\n# smt-sync\n```\n\n- List Repositories\n\n```\n# smt-repos\n```\n\n- Install the repositories you need to mirror via the smt-repos -e flag. For example to mirror SLES12-SP3-Pool\n\n```\n# smt-repos -e SLES12-SP3-Pool\n```\n\n- Check the enabled repos\n\n```\n# smt-repos -o\n```\n\n- Mirror the repositories\n\n```\n# smt-mirror\n```\n\n- This should install an apache2 on that host\nYou should be able to navigate to the mirror by browsing to http://<fqdn>/repo/\n\nCreate Products and Repositories\n\n- Follow the steps listed here to create Products and Repositories\n- Follow the steps listed on the same link as above to create a yum repository with the repository url pointing to the appropriate location. For example http://<fqdn>/repo/SUSE/Products/SLE-SERVER/12-SP3/x86_64/product/\n\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nSetup Remote Databases in Foreman with\nKatello Plugin Installed\n\nForeman with Katello plugin can be installed with remote databases for both postgresql and mongo. These instructions are for a Foreman with Katello plugin server, where remote databases are currently supported. This guide will refer to the server as “Foreman”, with the assumption that the Katello plugin is installed.\n\nHigh level\n\nThere are two ways to deploy Foreman with remote databases:\n\n1. **Fresh install**\n - prepare Postgres server with databases for Foreman and Candlepin and dedicated users owning them\n - prepare Mongo DB with user owning the pulp_database\n - prepare box where the Foreman will be installed and make sure the databases are accessible from the box\n - run foreman-installer with right parameters pointing to the databases\n\n2. **Migration of existing Foreman installation**\n - prepare Postgres server with databases for Foreman and Candlepin and dedicated users owning them\n - prepare Mongo DB with user owning the pulp_database\n - make sure the databases are accessible from the box where Foreman is installed\n - shut down the services except the dbs you want to move (mongod, postgresql)\n - dump the DBs\n - restore the DBs on remote servers\n - run foreman-installer with right parameters pointing to the databases. It re-configures the databases and start all the services with new DB locations\n\nIn either scenario, both of the databases don’t have to be remote. You can opt to use only a remote mongo database or only a remote postgresql database. Both postgresql and mongo databases can be on the same host, but this isn’t recommended due to the amount of resources mongo can use.\n\nPrepare remote Postgres\n\n**GOAL:** To use remote Postgres database with Foreman we have to:\n\n- be able to access the databases from foreman box\n- the database user we use to connect to the database needs to own the database, i.e. it can create, alter and delete the tables, indexes and constraints. Note it is not required to be able to create the database itself.\n\nInstall Postgres\n\n**Warning:** This is just minimal testing setup which is not suitable for production, please adjust the settings to your environment as needed.\n\nAssume our postgres server has hostname `postgres.example.com`.\n\nFirst, we install postgresql.\n\n```\nyum install -y postgresql-server postgresql-contrib\npostgresql-setup initdb\nsystemctl enable --now postgresql\n```\n\nNow we need to make Postgres listen to inbound connections, please adjust these parameters to your own networking and security requirements.\n\nEdit `/var/lib/pgsql/data/postgresql.conf`. Uncomment `listen_address` and modify its value to look like:\n\n```\nlisten_address = \"***\"\n```\n\nThe next step we need to take is to add a proper client authentication for remote client to our postgres server. To achieve the same, edit `/var/lib/pgsql/data/pg_hba.conf`. Append the following line at the end of the file\n\n```\nhost all all <katello.example.com ip>/24 md5\n```\n\nNow restart the postgres service for changes to take effect\n\n```\nsystemctl restart postgresql\n```\n\nCreate the databases\nSwitch the user role to postgres and start postgres client\n\n```\nsu - postgres -c psql\n```\n\nOnce inside the client, we need to create two databases and dedicated roles, one for foreman and one for candlepin.\n\n```\nCREATE USER \"foreman\" WITH PASSWORD '<FOREMAN_PASSWORD>';\nCREATE USER \"candlepin\" WITH PASSWORD '<CANDLEPIN_PASSWORD>';\nCREATE DATABASE foreman OWNER foreman;\nCREATE DATABASE candlepin OWNER candlepin;\n```\n\nTest it works\n\nFrom katello.example.com test the DB is accessible:\n\n```\nPGPASSWORD='<FOREMAN_PASSWORD>' psql -h postgres.example.com -p 5432 -U foreman -d foreman -c \"SELECT 1 as ping\"\nPGPASSWORD='<CANDLEPIN_PASSWORD>' psql -h postgres.example.com -p 5432 -U candlepin -d candlepin -c \"SELECT 1 as ping\"\n```\n\nIf there are no errors we are done with database preparation.\n\nPrepare remote Mongo\n\nGOAL: To use remote Mongo database with Foreman we have to:\n\n- be able to access the databases from foreman box\n- the database user we use to connect to the database needs to own the database\n\nInstall Mongo DB\n\nWarning: This is just minimal testing setup which is not suitable for production.\n\nAssume our Mongo server has hostname mongo.example.com. Install and enable Mongo server\n\n```\nyum install -y centos-release-scl\nyum install -y rh-mongodb34-syspaths\n```\n\nEnable authentication in `/etc/mongod.conf`\n\n```\nauth=true\n```\n\nEnable and start the service\n\n```\nsystemctl enable --now mongod\n```\n\nCreate Pulp user and database\n\n```\nmongo admin -u admin -p admin --eval \"db.createUser({user:'pulp',pwd:'<PULP_PASSWORD>',roles:[{role:'dbOwner', db:'pulp_database'}, { role: 'readWrite', db: 'pulp_database'}]})\"\nmongo --host mongo.example.com -u pulp -p <PULP_PASSWORD> --port 27017 --eval 'ping:1' pulp_database\n```\n\nTest it works\n\nFrom katello.example.com test the mongo DB is accessible:\n\n```\nmongo --host mongo.example.com -u pulp -p <PULP_PASSWORD> --port 27017 --eval 'ping:1' pulp_database\n```\n\nIf there are no errors we are done with database preparation.\n\nFresh install\n\nInstall katello package\n\nWe assume the box where the Foreman server will be installed has hostname katello.example.com.\nFollow the documentation to install the katello package and do not run foreman-installer. We need to use the remote database flags with the installer. Use the following steps once the katello rpm is installed.\n\n**Prepare remote databases**\n\nFollow the instructions to prepare remote mongo and prepare remote postgres to make the remote database servers ready for installation.\n\n**Run the installer**\n\nTo install and configure Foreman we just need to run\n\n```\nforeman-installer --scenario katello \\ \n--foreman-db-host postgres.example.com \\ \n--foreman-db-password <FOREMAN_PASSWORD> \\ \n--foreman-db-database foreman \\ \n--foreman-db-manage false \\ \n--katello-candlepin-db-host postgres.example.com \\ \n--katello-candlepin-db-name candlepin \\ \n--katello-candlepin-db-password <CANDLEPIN_PASSWORD> \\ \n--katello-candlepin-manage-db false \\ \n--katello-pulp-db-username pulp \\ \n--katello-pulp-db-password <PULP_PASSWORD> \\ \n--katello-pulp-db-seeds \"mongo.example.com:27017\" \\ \n--katello-pulp-db-name pulp_database \\ \n--katello-pulp-manage-db false\n```\n\nNote: for more related options and tips on SSL configuration see Full list of options\n\n**Migration of existing Foreman**\n\nMigrating an existing installation to remote databases can take time, so plan for some outage time (length depending on database size) while a backup is taken and the databases are migrated.\n\nIn this example, we assume that Foreman was installed and is running on katello.example.com.\n\n**Prepare remote databases**\n\nFollow the instructions to prepare remote mongo and prepare remote postgres to make the remote database servers ready for migration.\n\n**Stop the Foreman server**\n\nStop the Foreman related services to minimize risk of the data changes during the migration\n\n```\nkatello-service stop\nsystemctl start postgresql mongod\n```\n\n**Dump databases**\n\nDump the local databases\n\n```\nforeman-maintain backup online --skip-pulp-content --preserve-directory -y /tmp/migration_backup\n```\n\n**Restore data in remote databases**\n\nYou can restore the SQL dumps to the remote databases from the foreman system.\n\n```\nPGPASSWORD='<FOREMAN_PASSWORD>' pg_restore -h postgres.example.com -U foreman -d foreman < /tmp/migration_backup/foreman.dump\nPGPASSWORD='<CANDLEPIN_PASSWORD>' pg_restore -h postgres.example.com -U candlepin -d candlepin < /tmp/migration_backup/candlepin.dump\nmongorestore --host mongo.example.com --db pulp_database --username pulp --password <PULP_PASSWORD> /tmp/migration_backup/mongo_dump\n```\n\nNow the copy of the local database is also at the remote locations.\n\n**Update the configuration**\n\nTo update existing configuration of Foreman we just need to run\nThe installer starts services aside from the database related services. Everything should be up and ready at this point, and you can clean up the local databases if you would like.\n\nFull list of remote database related options in the installer\n\nUse `foreman-installer --full-help` for all up-to-date installer options\n\nForeman database related:\n\n- `-foreman-db-manage`\\ If enabled, will install and configure the database server on this host\n- `-foreman-db-host`\\ Database 'production' host\n- `-foreman-db-password`\\ Database 'production' password, default is randomly generated\n- `-foreman-db-database`\\ Database 'production' size of connection pool (current: 5)\n- `-foreman-db-port`\\ Database 'production' port\n- `-foreman-db-root-cert`\\ Root cert used to verify SSL connection to postgres\n- `-foreman-db-salmode`\\ Database 'production' ssl mode (disable|allow|prefer|required|verify-full)\n- `-foreman-db-username`\\ Database 'production' user (e.g. foreman)\n\nCandlepin database related:\n\n- `-katello-candlepin-db-host`\\ Host with Candlepin DB\n- `-katello-candlepin-db-name`\\ Name of the Candlepin DB\n- `-katello-candlepin-db-password`\\ Candlepin DB password\n- `-katello-candlepin-db-port`\\ Port accepting connections to Candlepin DB\n- `-katello-candlepin-db-ssl`\\ Boolean indicating if the connection to the database should be over SSL\n- `-katello-candlepin-db-ssl-verify`\\ Boolean indicating if the SSL connection to the database should be verified\n- `-katello-candlepin-db-user`\\ Candlepin DB user\n- `-katello-candlepin-manage-db`\\ Boolean indicating whether a database should be installed, this includes db creation and user\n\nMongo database related:\n\n- `-katello-pulp-db-ca-path`\\ The ca_certs file contains a set of concatenated \"certification authority\" certificates,\n- `-katello-pulp-db-name`\\ The name of the database to use\n- `-katello-pulp-db-password`\\ The password to use for authenticating to the MongoDB server\n- `-katello-pulp-db-replica-set`\\ The name of replica set configured in MongoDB, if one is in use\n- `-katello-pulp-db-seeds`\\ Comma-separated list of hostname:port of database replica seed hosts\n- `-katello-pulp-db-ssl-certfile`\\ The certificate file used to identify the local connection against mongod.\n- `-katello-pulp-db-ssl-keyfile`\\ A path to the private keyfile used to identify the local connection against mongod. If not specified and `--katello-pulp-db-ssl` is true, mongod will be configured to allow insecure connection.\n- `-katello-pulp-db-unsafe-autoretry`\\ If true, retry commands to the database if there is a connection error.\n- `-katello-pulp-db-verify-ssl`\\ Specifies whether a certificate is required from the other side of the connection, and allows the database to connect to an untrusted server\n- `-katello-pulp-db-write-concern`\\ Write concern of 'majority' or 'all'. When 'all' is specified, 'w' is set to number of replicas.\n\nSSL configuration\n\nHere is sample installer command that sets up Postgres databases with SSL verification. The Postgres server has its own CA. The CA cert used by Candlepin needs to be stored in system trust (`/etc/pki/java/cacerts`) as there is no other way to pass it to Candlepin.\n\n```bash\nforeman-installer --scenario katello\n--foreman-admin-password changeme\n--foreman-db-host postgres.example.com\n--foreman-db-password foreman\n--foreman-db-database foreman\n--foreman-db-manage false\n--katello-candlepin-db-host postgres.example.com\n--katello-candlepin-db-name candlepin\n--katello-candlepin-db-password <CANDLEPIN_PASSWORD\n--katello-candlepin-db-manage-db false\n--katello-pulp-db-username pulp\n--katello-pulp-db-password <PULP_PASSWORD\n--katello-pulp-db-seeds \"mongo.example.com:27017\"\n--katello-pulp-db-name pulp_database\n--katello-pulp-manage-db false\n```\n\nThe actual option names may vary between versions. Check the actual naming with `foreman-installer --full-help`.\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\n\nView our Privacy Policy\nThis web site is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License. Source available: github/theforeman/theforeman.org\nThanks to our sponsors for hosting this website and our project services.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. API Documentation\n8. Annotated Backend Requests\n\nKatello Troubleshooting\nFor general support information, see here.\nSub-services status\n\nKatello uses a set of back-end services to perform the actual job. The status of these services can negatively influence the whole system and it's one of the first things to check when some errors occur.\n\nThe status of back-end services can be found either from the Web UI on the `/about` page:\n\n\n\nAlternatively, the `hammer ping` command can be used to get this information.\n\n`katello-service` tool can be used to restart Katello related services. See `man katello-service` for more details.\n\nTasks\n\nKatello uses Foreman Tasks for orchestration between the underlying services (local database, Pulp, Candlepin...). The tasks are modeled as Dynflow processes. When something goes wrong (and there might be many reasons for this happening), Dynflow gives us the tools to recover from these errors to get to the consistent state.\n\nHealth checking\n\nThere are two properties used for identifying issues with a task:\n\n- **state** - what phase of execution is the task in, possible values are:\n - **planning** - the planning phase of the task is performed: the operations performed in this phase shouldn't modify anything outside Katello's database. The execution of this phase happens in the web-process thread and usually should not take more than a few seconds\n - **planned** - the planning phase finished and the task is waiting for the executor process (foreman-tasks service) to pick it up\n - **running** - the executor is performing the orchestration action, modifying the state of external services to converge to the final state\n - **paused** - something went wrong during running the task and it's waiting for the resolution (further details below)\n - **stopped** - the execution of the task finished (the success is determined by the `result` value)\n - **result** - how the task ended up (or is going to end up if we already know it)\n - **pending** - task is in the process of executing\n - **success** - no errors occurred during the execution\n - **error** - unresolved errors occurred during the execution\n - **warning** - there were errors during the execution, but they did not prevent the task from finishing or were skipped\nTo see all the tasks in the system, one can go to `/foreman_tasks/tasks` page. To see all the tasks that failed, one can search on `result = error`:\n\nFailed tasks include those in the 'stopped' or 'paused' state. The stopped tasks are already considered as resolved, there is no risk of inconsistency. The tasks in the 'stopped' state and the 'error' result are usually those failed during the planning phase (usually locking error or bad input data).\n\nTo see all the tasks requiring further assistance, filter on `state = paused`:\n\nDealing with paused task\n\nOnce the paused task is identified, one can investigate the problem causing the errors:\nThe resolution of the problem is dependent on the error details. The task may be resolvable by resuming the task: make sure the sub-services are running (see Sub-services status for more details) and then click ‘Resume’ within the web interface.\n\nIf this still doesn’t help, one possible step is going to a Dynflow console (the button from task details takes you there):\n\nCaution: Dynflow console is considered a low-level tool and should be used very carefully, ideally discussing other options before using its features.\n\nIf the failed task was taken care of by other means (performing the failed steps manually) or it was identified as not critical to the whole task, one can skip the failed step and resume the task to continue. These tasks end up with warning result at the end, to indicate there was some difficulty during the run.\n\nDealing with Long Running Tasks\n\nIn some cases, there might be an issue with sub-services that make it appear as if the task is running for too long without any obvious evidence that something is occurring within the task.\n\nThe first place to look in this case is filtering the tasks on state = running and looking at Running Steps in the task details:\nIn this case, the \"start_time\" => nil indicates that the task was not picked up by Pulp, which usually means some issues with running the Pulp workers. See (see Sub-services status for more details).\n\nOne can also go to the Dynflow console for even more details: the suspended state means that the step is waiting for the external task to finish - the suspended state itself doesn't have to indicate any error:\n\nIf you're sure the underlying services are running fine, depending on the type of task, there might be a possibility to cancel the running step and possibly following dealing with paused tasks instead.\nLocking\n\nForeman tasks provides a locking mechanism which is important to prevent the possibility of operations colliding that are being performed concurrently on the same resource (such as synchronizing and deleting a repository at the same time).\n\nWhen trying to run an operation on a resource that another task is already running, one can get required lock is already taken by other running tasks.\n\nA locked resource is one where another task that is related to the same resource is already running. Thus, the task being attempted will result in that task being tried in running or paused state. This means that the error is triggered also in cases, where there is a task with unresolved failure (see dealing with paused tasks for more details).\n\nIn rare cases, it might be hard to get into the stopped state. There is a possibility to unlock the resource in the running/paused task. This will switch the task into stopped state, freeing the resources for other tasks. Caution: unlocking allows running other tasks to run on potentially inconsistent data, which might lead into further errors. It's still possible to go to the Dynflow console and resume the tasks, even after using the unlock feature. There are two unlock-related buttons: Unlock and Force Unlock. The only difference between these two is the second one is allowed even when the task is in running state, and therefore is potentially even more dangerous than the Unlock button. See dealing with tasks running too long before attempting to use the Force Unlock option.\n\nDebug Certificate\n\nDebug certificates (also called Ueber Certificates) can be used to unlock all the content for a given Organization. These are meant to be used by sysadmins who are debugging issues with the Katello install.\n\nGenerating a Debug Certificate\n\nTo generate a debug certificate for a given Organization from the UI, navigate to the organizations page and click on the organization for which you want a debug certificate. Click on the button to generate and download the certificate as highlighted below:\nTo generate a debug certificate using the API see the API docs located on your server running at `/apidoc`.\n\nIn either case, you will get the Private Key and Certificate returned to you in a format such as:\n\n```\nKey: -----BEGIN RSA PRIVATE KEY-----\n<<<<DER ENCODED TEXT>>>>\n-----END RSA PRIVATE KEY-----\n```\n\n```\nCert: -----BEGIN CERTIFICATE-----\n<<<<DER ENCODED TEXT>>>>\n-----END CERTIFICATE-----\n```\n\nUsing Firefox to browse content\n\nIf you wish to use the certificate to browse content via Firefox, do the following:\n\n1. Copy the contents of the above file from `-----BEGIN RSA PRIVATE KEY-----` to `-----END RSA PRIVATE KEY-----` inclusive to a file called `key.pem`\n2. Copy the contents of the above file from `-----BEGIN CERTIFICATE-----` to `-----END CERTIFICATE-----` inclusive to a file called `cert.pem`\n3. Run the following command to create a pkcs12 file:\n\n```\nopenssl pkcs12 -keypbe PBE-SHA1-3DES -certpbe PBE-SHA1-3DES -export -in cert.pem -inkey key.pem -out [NAME].pfx -name [NAME]\n```\n\n4. Provide a password when prompted.\n5. Using the preferences tab, import the resulting pfx file into your browser (Edit->Preferences->Advanced Tab -> View Certificates -> Import)\n6. Point your browser at `http://[FQDN]/pulp/repos/[ORG_NAME]`\n\nTo use curl to access the repository, you can provide `-cert` and `-key` options. Provided the cert is in `~/cert.pem` and key in `~/key.cert`, the following command will let you access any repository data in the organization. To check the access to a repository, checking the availability of `repodata/repomd.xml` is usually a good idea (make sure `key.pem` and `cert.pem` are \"absolute paths\" otherwise it silently fails):\n\n```\n```\n\nFrequently Asked Questions\n\nCan I use pulp-admin with Katello?\nWe do not encourage the use of pulp-admin because it has the potential to get data out of sync. However, pulp-admin can be useful when troubleshooting Katello.\n\n1. Install needed packages\n \n ```sh\n yum install -y pulp-admin-client pulp-rpm-admin-extensions\n ```\n\n2. Edit `/etc/pulp/admin/admin.conf`\n3. Uncomment the `host:` line and add your server's hostname:\n \n ```plaintext\n host: katello-hostname.example.com\n ```\n\n4. Run `grep default_password /etc/pulp/server.conf` to lookup the admin password\n\n ```sh\n sudo grep default_password /etc/pulp/server.conf\n ```\n\n5. Use pulp-admin by specifying the admin username and password:\n\n ```sh\n pulp-admin -u admin -p default_password repo list\n ```\n\nUsing pulp-admin without password\n\nUsing the `pulp-admin login` command does not function and is not supported with Katello in an attempt to limit access to the certificate authority generated at installation time.\n\nKatello 3.0 generates a client cert at installation time which allows usage of pulp-admin without specifying the username and password. To use this:\n\n1. `mkdir ~/.pulp`\n2. Copy the public client cert and private key to a file together:\n\n ```sh\n # sudo cat /etc/pki/katello/certs/pulp-client.crt /etc/pki/katello/private/pulp-client.key > ~/.pulp/user-cert.pem\n ```\n3. Run pulp-admin without username and password:\n\n ```sh\n pulp-admin repo list\n ```\n\nHow can I sync a repository like Katello does directly from the console?\n\nSometimes you want to debug why a synchronization of a repository from Katello is failing and rather than dig through log files and error messages it can often be easier to try to sync the repo with the \"grinder\" tool which is what Katello uses to download repositories. The tool can be ran from a terminal on your Katello server:\n\n```sh\n$ grinder yum --label=sync-test --url=http://fedorapeople.org/groups/katello/releases/yum/1.0/RHEL/6Server/x86_64/\ngrinder.RepoFetch: INFO fetchYumRepo() repo_label = sync-test, repo_url = http://fedorapeople.org/groups/katello/releases/yum/1.0/RHEL/6Server/x86_64/, basepath = ./, verify_options = {}\ngrinder.RepoFetch: INFO sync-test, http://fedorapeople.org/groups/katello/releases/yum/1.0/RHEL/6Server/x86_64/, Calling RepoFetch with: cacert=<None>, clicert=<None>, clikey=<None>, proxy_url=<None>, proxy_port=<3128>, proxy_user=<None>, proxy_pass=<NOT_LOGGED>, ssverify=<1>, max_speed=<None>, verify_options=<{}>, filter=<None>\n grinder.ParallelFetch: INFO 5 threads are active. 8 items left to be fetched\n grinder.ParallelFetch: INFO 4 threads are active. 4 items left to be fetched\n grinder.ParallelFetch: INFO WorkerThread deleting ActiveObject\n grinder.ParallelFetch: INFO 3 threads are active. 3 items left to be fetched\n grinder.ParallelFetch: INFO WorkerThread deleting ActiveObject\n grinder.ParallelFetch: INFO Thread ending\n grinder.ParallelFetch: INFO Thread ending\n grinder.ParallelFetch: INFO Thread ending\n $ ls sync-test/\n converge-ui-devel-0.8.3-1.el6.noarch.rpm\n elasticsearch-0.18.4-13.el6.noarch.rpm\n katello-1.0.6-1.el6.noarch.rpm\n katello-agent-1.0.6-1.el6.noarch.rpm\n katello-all-1.0.6-1.el6.noarch.rpm\n katello-certs-tools-1.1.7-1.el6.noarch.rpm\n lucene3-contrib-3.4.0-2.el6.noarch.rpm\n repodata\n rubygem-actionmailer-3.0.10-3.el6.noarch.rpm\n ...\n```\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nForeman API v2 is currently the default API version.\n\n## Resources\n\n### Activation keys\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>GET /katello/api/activation_keys</td>\n<td>List activation keys</td>\n</tr>\n<tr>\n<td>GET /katello/api/organizations/organization_id/activation_keys</td>\n<td></td>\n</tr>\n<tr>\n<td>GET /katello/api/environments/environment_id/activation_keys</td>\n<td></td>\n</tr>\n<tr>\n<td>POST /katello/api/activation_keys</td>\n<td>Create an activation key</td>\n</tr>\n<tr>\n<td>PUT /katello/api/activation_keys/id</td>\n<td>Update an activation key</td>\n</tr>\n<tr>\n<td>DELETE /katello/api/activation_keys/id</td>\n<td>Destroy an activation key</td>\n</tr>\n<tr>\n<td>GET /katello/api/activation_keys/id</td>\n<td>Show an activation key</td>\n</tr>\n<tr>\n<td>POST /katello/api/activation_keys/id/copy</td>\n<td>Copy an activation key</td>\n</tr>\n<tr>\n<td>GET /katello/api/activation_keys/id/host_collections/available</td>\n<td>List host collections the activation key does not belong to</td>\n</tr>\n<tr>\n<td>GET /katello/api/activation_keys/id/releases</td>\n<td>Show release versions available for an activation key</td>\n</tr>\n<tr>\n<td>GET /katello/api/activation_keys/id/product_content</td>\n<td>Show content available for an activation key</td>\n</tr>\n<tr>\n<td>POST /katello/api/activation_keys/id/host_collections</td>\n<td></td>\n</tr>\n<tr>\n<td>PUT /katello/api/activation_keys/id/add_subscriptions</td>\n<td>Attach a subscription</td>\n</tr>\n<tr>\n<td>PUT /katello/api/activation_keys/id/remove_subscriptions</td>\n<td>Unattach a subscription</td>\n</tr>\n<tr>\n<td>PUT /katello/api/activation_keys/id/content_override</td>\n<td>Override content for activation_key</td>\n</tr>\n</tbody>\n</table>\n\n### Architectures\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>GET /api/architectures</td>\n<td>List all architectures</td>\n</tr>\n</tbody>\n</table>\nForeman 2.3.3 has been released! Follow the quick start to install it.\nForeman 2.2.2 has been released! Follow the quick start to install it.\nKatello 3.7 Documentation\n\n1. Installation\n 1.1 Katello\n 1.2 Smart proxy\n 1.3 Clients\n2. Upgrade\n 2.1 Katello\n 2.2 Smart proxy\n 2.3 Clients\n3. Release Notes\n4. CLI\n5. User Guide\n 5.1 Activation Keys\n 5.2 Backup\n 5.3 Foreman proxy\n 5.4 Content\n 5.5 Content Hosts\n 5.6 Content Views\n 5.7 Disconnected\n 5.8 Docker Management\n 5.9 Email Notifications\n 5.10 Errata\n 5.11 Glossary\n 5.12 Content Credentials\n 5.13 Host Collections\n 5.14 Lifecycle Environments\n 5.15 Provisioning\n 5.16 Puppet Integration\n 5.17 Red Hat Content\n 5.18 SUSE Content\n 5.19 Remote Databases\n6. Troubleshooting\n7. Api Documentation\n8. Annotated Backend Requests\n\nRepository Sync (default settings)\nRequest # 1:\n\n**POST /pulp/api/v2/repositories/scenario_test/actions/sync/**\n\nBackend Service: pulp\n\nDescription:\n\nRequest body\n\n```json\n{\n \"override_config\": {\n \"num_threads\": 4,\n \"validate\": true\n }\n}\n```\n\nResponse body\n\n```json\n{\n \"spawned_tasks\": [\n {\n \"_href\": \"/pulp/api/v2/tasks/8b9c7591-4d1b-48b7-b37b-bce4fde9c2fd/\",\n \"task_id\": \"8b9c7591-4d1b-48b7-b37b-bce4fde9c2fd\",\n \"result\": null,\n \"error\": null\n }\n ],\n \"result\": null,\n \"error\": null\n}\n```\n\nRequest # 2: Poll Sync task\n\n**GET /pulp/api/v2/tasks/8b9c7591-4d1b-48b7-b37b-bce4fde9c2fd/**\n\nBackend Service: pulp\n\nDescription:\n\nTotal Requests for this URL: 32\n\nRequest body\n\nNone\n\nResponse body\n\n```json\n{\n \"exception\": null,\n \"task_type\": \"pulp.server.managers.repo.sync.sync\",\n \"href\": \"/pulp/api/v2/tasks/8b9c7591-4d1b-48b7-b37b-bce4fde9c2fd/\",\n \"task_id\": \"8b9c7591-4d1b-48b7-b37b-bce4fde9c2fd\",\n \"tags\": [\n \"pulp:repository:scenario_test\",\n \"pulp:action:sync\"\n ],\n\n \"finish_time\": \"2017-03-30T21:16:05Z\",\n \"ns\": \"task_status\",\n \"start_time\": \"2017-03-30T21:16:05Z\",\n \"traceback\": null,\n \"spawned_tasks\": [\n {\n \"_href\": \"/pulp/api/v2/tasks/0837f608-4696-449a-811f-70ddabe59025/\",\n \"task_id\": \"0837f608-4696-449a-811f-70ddabe59025\"\n }\n ],\n \"progress_report\": {\n \"yum_importer\": {\n \"content\": {\n \"items_total\": 0,\n \"state\": \"FINISHED\",\n \"error_details\": [\n {\n \"rpm_total\": 0,\n \"rpm_done\": 0,\n \"drpm_total\": 0,\n \"drpm_done\": 0,\n \"size_total\": 0,\n \"size_left\": 0,\n \"items_left\": 0\n }\n ]\n },\n \"comps\":\n }\n }\n}\n```\nRequest # 3: Poll Publish task\n\nGET /pulp/api/v2/tasks/0837f608-4696-449a-811f-70ddabe59025/\n\nBackend Service: pulp\n\nDescription:\nTotal Requests for this URL: 12\n\nRequest body\nNone\n\nResponse body\n\n```\n{\n \"exception\": null,\n \"task_type\": \"pulp.server.managers.repo.publish.publish\",\n \"_href\": \"/pulp/api/v2/tasks/0837f608-4696-449a-811f-70ddabe59025/\",\n \"task_id\": \"0837f608-4696-449a-811f-70ddabe59025\",\n \"tags\": [],\n \"_ns\": \"task_status\",\n \"finish_time\": \"2017-03-30T21:16:05Z\",\n \"start_time\": \"2017-03-30T21:16:05Z\",\n \"traceback\": null,\n \"spawned_tasks\": [],\n \"progress_report\": {\n \"scenario_test\": [\n {\n \"num_success\": 1,\n \"description\": \"Copying files\",\n \"step_type\": \"save_tar\",\n \"items_total\": 1,\n \"state\": \"FINISHED\",\n \"error_details\": []\n },\n {\n \"num_success\": 1,\n \"description\": \"Initializing repo metadata\",\n \"step_type\": \"initialize_repo_metadata\",\n \"items_total\": 1,\n \"state\": \"FINISHED\",\n \"error_details\": []\n },\n {\n \"num_success\": 1,\n \"description\": \"Publishing Distribution files\",\n \"step_type\": \"distribution\",\n \"items_total\": 1,\n \"state\": \"FINISHED\",\n \"error_details\": []\n },\n {\n \"num_success\": 8,\n \"description\": \"Copying files\",\n \"step_type\": \"save_tar\",\n \"items_total\": 8,\n \"state\": \"FINISHED\",\n \"error_details\": []\n }\n ],\n \"repository_test\": [\n {\n \"num_success\": 1,\n \"description\": \"Copying files\",\n \"step_type\": \"save_tar\",\n \"items_total\": 1,\n \"state\": \"FINISHED\",\n \"error_details\": []\n }\n ]\n },\n \"metadata\": {\n \"state\": \"FINISHED\"\n }\n}\n```\n<table>\n<thead>\n<tr>\n<th>Step ID</th>\n<th>Description</th>\n<th>Step Type</th>\n<th>Items Total</th>\n<th>State</th>\n<th>Error Details</th>\n<th>Details</th>\n<th>Num Failures</th>\n<th>Num Processed</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>197b0894-07fd-470b-8bb4-5a55b9713d18</td>\n<td>Publishing RPMs</td>\n<td>rpms</td>\n<td>8</td>\n<td>FINISHED</td>\n<td></td>\n<td></td>\n<td>0</td>\n<td>8</td>\n</tr>\n<tr>\n<td>54795382-de70-4de3-a8ce-5f726b8f9cb2</td>\n<td>Publishing Delta RPMs</td>\n<td>drpms</td>\n<td>1</td>\n<td>SKIPPED</td>\n<td></td>\n<td></td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>1996449c-9471-4988-b3ee-b7ceae0c6b41</td>\n<td>Publishing Errata</td>\n<td>errata</td>\n<td>3</td>\n<td>FINISHED</td>\n<td></td>\n<td></td>\n<td>0</td>\n<td>3</td>\n</tr>\n<tr>\n<td>f12472f5-4012-4112-afe0-49f57348e569</td>\n<td>Publishing Comps file</td>\n<td>comps</td>\n<td>3</td>\n<td>FINISHED</td>\n<td></td>\n<td></td>\n<td>0</td>\n<td>3</td>\n</tr>\n<tr>\n<td>31efb1ef-a413-48be-99f2-7f4788a1cebd</td>\n<td>Publishing Metadata</td>\n<td>metadata</td>\n<td>0</td>\n<td>FINISHED</td>\n<td></td>\n<td></td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>22b9313d-ffae-49e3-8027-c86ef68f34de</td>\n<td>Closing repo metadata</td>\n<td>close_repo_metadata</td>\n<td>1</td>\n<td>FINISHED</td>\n<td></td>\n<td></td>\n<td>0</td>\n<td>1</td>\n</tr>\n<tr>\n<td>fbc75485-e400-4cfa-bfa7-693edd8a832c</td>\n<td>Generating sqlite files</td>\n<td>generate sqlite</td>\n<td>1</td>\n<td>SKIPPED</td>\n<td></td>\n<td></td>\n<td>0</td>\n<td>0</td>\n</tr>\n</tbody>\n</table>\n```json\n{\n \"step_id\": \"fbc75d85-e400-4cla-bfa7-693edd8a832c\",\n \"num_processed\": 0,\n \"num_success\": 0,\n \"description\": \"Generating HTML files\",\n \"step_type\": \"repoview\",\n \"items_total\": 1,\n \"state\": \"SKIPPED\",\n \"error_details\": [\n \n ],\n \"details\": \"\",\n \"num_failures\": 0,\n \"step_id\": \"bf1215fe-c617-4481-894a-1ff1c7c7043b\",\n \"num_processed\": 0,\n \"num_success\": 1,\n \"description\": \"Publishing files to web\",\n \"step_type\": \"publish_directory\",\n \"items_total\": 1,\n \"state\": \"FINISHED\",\n \"error_details\": [\n \n ],\n \"details\": \"\",\n \"num_failures\": 0,\n \"step_id\": \"605ae2e4-c443-4a5b-ba9f-f313d23c4822\",\n \"num_processed\": 1,\n \"num_success\": 1,\n \"description\": \"Writing Listings File\",\n \"step_type\": \"initialize_repo_metadata\",\n \"items_total\": 1,\n \"state\": \"FINISHED\",\n \"error_details\": [\n \n ],\n \"details\": \"\",\n \"num_failures\": 0,\n \"step_id\": \"9fa215e9-b465-4f33-9ddd-e05c5a9e314d\",\n \"num_processed\": 1,\n \"num_success\": 1,\n \"description\": \"Copying files\",\n \"step_type\": \"save_tar\",\n \"items_total\": 1,\n \"state\": \"FINISHED\",\n \"error_details\": [\n \n ],\n \"details\": \"\",\n \"num_failures\": 0,\n \"step_id\": \"8fa5d08e-3473-4127-80f6-223bee0a0409\",\n \"num_processed\": 1,\n \"queue\": \"reserved_resource_worker-1@dev.example.com.dq\",\n \"state\": \"finished\",\n \"worker_name\": \"reserved_resource_worker-1@dev.example.com\",\n \"result\": {\n \"result\": \"success\",\n \"exception\": null,\n \"repo_id\": \"scenario_test\",\n \"started\": \"2017-03-30T21:16:05Z\",\n \"ns\": \"repo_publish_results\",\n \"completed\": \"2017-03-30T21:16:05Z\",\n \"traceback\": null,\n \"distributor_type_id\": \"yum_distributor\",\n \"summary\": {\n \"generate sqlite\": \"SKIPPED\",\n \"initialize_repo_metadata\": \"FINISHED\",\n \"rpm\": \"FINISHED\",\n \"repoview\": \"SKIPPED\",\n \"close_repo_metadata\": \"FINISHED\",\n \"drpms\": \"SKIPPED\",\n \"comps\": \"FINISHED\",\n \"distribution\": \"FINISHED\",\n \"save_tar\": \"FINISHED\",\n \"publish_directory\": \"FINISHED\",\n \"errata\": \"FINISHED\",\n \"metadata\": \"FINISHED\"\n },\n \"error_message\": null,\n \"distributor_id\": \"scenario_test\",\n \"id\": \"58dd7595418a8a0648b9bc53\",\n \"details\": {\n \"num_success\": 1,\n \"description\": \"Copying files\",\n \"step_type\": \"save_tar\",\n \"items_total\": 1,\n \"state\": \"FINISHED\",\n \"error_details\": [\n \n ],\n \"details\": \"\",\n \"num_failures\": 0,\n \"step_id\": \"8fa5d08e-3473-4127-80f6-223bee0a0409\",\n \"num_processed\": 1\n }\n }\n}```\n{ \"description\": \"Initializing repo metadata\", \"step_type\": \"initialize_repo_metadata\", \"items_total\": 1, \"state\": \"FINISHED\", \"error_details\": [ ] }, \n{ \"details\": \"\", \"num_failures\": 0, \"step_id\": \"32ce4d1-6e51-419a-9833-5f2c88a3ef09\", \"num_processed\": 1 }, \n{ \"num_success\": 1, \"description\": \"Publishing Distribution files\", \"step_type\": \"distribution\", \"items_total\": 1, \"state\": \"FINISHED\", \"error_details\": [ ] }, \n{ \"details\": \"\", \"num_failures\": 0, \"step_id\": \"d562a1815-acd5-439c-b511-dcbd69edade4\", \"num_processed\": 1 }, \n{ \"num_success\": 1, \"description\": \"Publishing RPMs\", \"step_type\": \"rpms\", \"items_total\": 1, \"state\": \"FINISHED\", \"error_details\": [ ] }, \n{ \"details\": \"\", \"num_failures\": 0, \"step_id\": \"197b0894-07fd-470b-8bb4-5a55b9713d18\", \"num_processed\": 1 }, \n{ \"num_success\": 8, \"description\": \"Publishing Delta RPMs\", \"step_type\": \"drpms\", \"items_total\": 1, \"state\": \"SKIPPED\", \"error_details\": [ ] }, \n{ \"details\": \"\", \"num_failures\": 0, \"step_id\": \"54779385-de70-4de3-8f9c-b8f97f26b89\", \"num_processed\": 1 }, \n{ \"num_success\": 3, \"description\": \"Publishing Errata\", \"step_type\": \"errata\", \"items_total\": 3, \"state\": \"FINISHED\", \"error_details\": [ ] }, \n{ \"details\": \"\", \"num_failures\": 0, \"step_id\": \"1996449c-9471-4988-b3ee-b7ce4e0c6b41\", \"num_processed\": 3 }, \n{ \"num_success\": 0, \"description\": \"Publishing Metadata.\", \"step_type\": \"metadata\", \"items_total\": 0, \"state\": \"FINISHED\", \"error_details\": [ ] }, \n{ \"details\": \"\", \"num_failures\": 0, \"step_id\": \"1947215-4012-41e2-a0e0-49f57348e569\", \"num_processed\": 3 }, \n{ \"num_success\": 0, \"description\": \"Publishing Metadata.\", \"step_type\": \"metadata\", \"items_total\": 0, \"state\": \"FINISHED\", \"error_details\": [ ] }, \n{ \"details\": \"\", \"num_failures\": 0, \"step_id\": \"31eb1ef-a413-48be-9ff2-7f4788a1ced\", \"num_processed\": 3 }\nRequest # 4: Distribution Search\n\nPOST /pulp/api/v2/repositories/scenario_test/search/units/\n\nBackend Service: pulp\n\nDescription: Search for distribution information with all fields\n\nRequest body\n\n```json\n{\n \"error\": null,\n \"id\": {\n \"$oid\": \"58dd7595e6919db96421ea23\"\n },\n \"id\": \"58dd7595e6919db96421ea23\"\n}\n```\nRequest # 5: Fetch rpm unit ids for this repo\n\nPOST /pulp/api/v2/repositories/scenario_test/search/units/\n\nBackend Service: pulp\n\nDescription:\n\nRequest body\n\n```json\n{\n \"criteria\": {\n \"type_ids\": [\n \"rpm\"\n ]\n }\n}\n```\nResponse body\nRequest # 6: Fetch rpm units for this repository\n\nPOST /pulp/api/v2/content/units/rpm/search/\n\nBackend Service: pulp\n\nDescription: Search for all rpms with the previously fetched ids. We do this because historically we’ve wanted the list of all repo ids for each unit, which is only available via this endpoint.\n\nRequest body\n\n```json\n{\n \"criteria\": {\n \"limit\": 8,\n \"skip\": 0,\n \"fields\": [\n \"name\",\n \"version\",\n \"release\",\n \"arch\",\n \"epoch\",\n \"summary\",\n \"sourcerpm\",\n \"checksum\",\n \"filename\",\n \"_id\"\n ],\n \"filters\": {\n \"_id\": {\n \"$in\": [\n \"085babbb-3a43-4b9c-bdfb-915fd78c7bec\",\n \"2b00d383-f2c7-462c-bfe3-25a008caaa0fe\",\n \"5ee1ec3a-7f81-47e6-bbba-11b443251f29\",\n \"6b8e61f7-c155-4cb9-a291-a93d05c8eac3\",\n \"7f14f62-7a47-4b20-072d-0d1549c527\",\n \"96b939b6-8411-093d0b1d1ec3\",\n \"d35640a0-8613-44bd-9e95-14122834087\",\n \"f521967-a646-436e-83-1ac9e5l87cd8\"\n ]\n }\n }\n },\n \"include_repos\": true\n}\n```\n\nResponse body\n\n```json\n{\n \"repository_memberships\": [\n {\n \"sourcerpm\": \"walrus-0.3-0.8.src.rpm\",\n \"name\": \"walrus\",\n \"checksum\": \"6b8e61f7-c155-4cb9-a291-a93d05c8eac3\",\n \"summary\": \"A dummy package of walrus\",\n \"filename\": \"walrus-0.3-0.8.noarch.rpm\",\n \"epoch\": 0,\n \"version\": \"0.3\",\n \"release\": \"0.8\",\n \"_id\": \"085babbb-3a43-4b9c-bdfb-915fd78c7bec\",\n \"arch\": \"noarch\",\n \"children\": [\n \"href\": \"pulp/api/v2/content/units/rpm/085babbb-3a43-4b9c-bdfb-915fd78c7bec\"\n ]\n },\n {\n \"sourcerpm\": \"penguin-0.3-0.8.src.rpm\",\n \"name\": \"penguin\",\n \"checksum\": \"7f14f62-7a47-4b20-072d-0d1549c527\",\n \"summary\": \"A dummy package of penguin\",\n \"filename\": \"penguin-0.3-0.8.noarch.rpm\",\n \"epoch\": 0,\n \"version\": \"0.3\",\n \"release\": \"0.8\",\n \"_id\": \"2b00d383-f2c7-462c-bfe3-25a008caaa0fe\",\n \"arch\": \"noarch\",\n \"children\": [\n \"href\": \"pulp/api/v2/content/units/rpm/2b00d383-f2c7-462c-bfe3-25a008caaa0fe\"\n ]\n },\n {\n \"sourcerpm\": \"elephant-0.3-0.8.src.rpm\",\n \"name\": \"elephant\",\n \"checksum\": \"d35640a0-8613-44bd-9e95-14122834087\",\n \"summary\": \"A dummy package of elephant\",\n \"filename\": \"elephant-0.3-0.8.noarch.rpm\",\n \"epoch\": 0,\n \"version\": \"0.3\",\n \"release\": \"0.8\",\n \"_id\": \"d35640a0-8613-44bd-9e95-14122834087\",\n \"arch\": \"noarch\",\n \"children\": [\n \"href\": \"pulp/api/v2/content/units/rpm/d35640a0-8613-44bd-9e95-14122834087\"\n ]\n }\n ]\n}\n```\n\"sourcerpm\": \"elephant-0.3-0.8.src.rpm\",\n\"name\": \"elephant\",\n\"checksum\": \"3e1c70cd1b421328aca6397c5d316145306bb95f65db0955c31372a0a70f3\",\n\"summary\": \"A dummy package of elephant\",\n\"filename\": \"elephant-0.3-0.8.noarch.rpm\",\n\"epoch\": \"0\",\n\"version\": \"0.3\",\n\"release\": \"0.8\",\n\"_id\": \"See1ec3a-7f81-47e6-bbba-11b443251f29\",\n\"arch\": \"noarch\",\n\"children\": []\n}\n}\n]\n]\nrepository_memberships\": [\n \"scenario_test\"\n]\n]\n]\n sourcerpm\": \"monkey-0.3-0.8.src.rpm\",\n\"name\": \"monkey\",\n\"checksum\": \"0e8fa50d0128fbabc7ccc5632e3fa25d39b0280169f6166cb8e2c8d8e8501db1\",\n\"summary\": \"A dummy package of monkey\",\n\"filename\": \"monkey-0.3-0.8.noarch.rpm\",\n\"epoch\": \"0\",\n\"version\": \"0.3\",\n\"release\": \"0.8\",\n\"_id\": \"Bea869197-c155-4c8c-a931-aa5b85bd218c\",\n\"arch\": \"noarch\",\n\"children\": []\n}\n}\n]\n]\nrepository_memberships\": [\n \"scenario_test\"\n]\n]\n]\n sourcerpm\": \"lion-0.3-0.8.src.rpm\",\n\"name\": \"lion\",\n\"checksum\": \"12400dc95c23a4c160725a908716cd3f891585437ab64cd62ea3e8ae4\",\n\"summary\": \"A dummy package of lion\",\n\"filename\": \"lion-0.3-0.8.noarch.rpm\",\n\"epoch\": \"0\",\n\"version\": \"0.3\",\n\"release\": \"0.8\",\n\"_id\": \"7f4f862-7ae7-4b20-b072-0d154a9cc527\",\n\"arch\": \"noarch\",\n\"children\": []\n}\n}\n]\n]\nrepository_memberships\": [\n \"scenario_test\"\n]\n]\n]\n sourcerpm\": \"cheetah-0.3-0.8.src.rpm\",\n\"name\": \"cheetah\",\n\"checksum\": \"422d0baa0cd9d7713ae796e886a23e171578f924f74880debdb7d65b368dse\",\n\"summary\": \"A dummy package of cheetah\",\n\"filename\": \"cheetah-0.3-0.8.noarch.rpm\",\n\"epoch\": \"0\",\n\"version\": \"0.3\",\n\"release\": \"0.8\",\n\"_id\": \"9f6b8fda-dd97-453e-8841-093305c8eac3\",\n\"arch\": \"noarch\",\n\"children\": []\n}\n}\n]\n]\nrepository_memberships\": [\n \"scenario_test\"\n]\n]\n]\n sourcerpm\": \"giraffe-0.3-0.8.src.rpm\",\n\"name\": \"giraffe\",\n\"checksum\": \"f25d67d1d9d9a04f12e657ca323247b43891ac46533e355b82de6d1922009f14\",\n\"summary\": \"A dummy package of giraffe\",\n\"filename\": \"giraffe-0.3-0.8.noarch.rpm\",\n\"epoch\": \"0\",\n\"version\": \"0.3\",\n\"release\": \"0.8\",\n\"_id\": \"9f6b8fda-dd97-453e-8841-093305c8eac3\",\n\"arch\": \"noarch\",\n\"children\": []\n}\n]\n]\nrepository_memberships\": [\n \"scenario_test\"\n]\n]\n]\n sourcerpm\": \"squirrel-0.3-0.8.src.rpm\",\n\"name\": \"squirrel\",\n\"checksum\": \"25176b9d15f378487c27638aa8aecd015511e253756093cde1c0a878a17d2\",\n\"summary\": \"A dummy package of squirrel\",\n\"filename\": \"squirrel-0.3-0.8.noarch.rpm\",\n\"epoch\": \"0\",\n\"version\": \"0.3\",\n\"release\": \"0.8\",\n\"_id\": \"d3964a9-8613-44bd-9e99-141af2843087\",\n\"arch\": \"noarch\",\n\"children\": []\n}\n]\n]\nrepository_memberships\": [\n \"scenario_test\"\n]\n]\n]\n sourcerpm\": \"squirrel-0.3-0.8.src.rpm\",\n\"name\": \"squirrel\",\n\"checksum\": \"25176b9d15f378487c27638aa8aecd015511e253756093cde1c0a878a17d2\",\n\"summary\": \"A dummy package of squirrel\",\n\"filename\": \"squirrel-0.3-0.8.noarch.rpm\",\n\"epoch\": \"0\",\n\"version\": \"0.3\",\n\"release\": \"0.8\",\n\"_id\": \"d3964a9-8613-44bd-9e99-141af2843087\",\n\"arch\": \"noarch\",\n\"children\": []\n}\n]\n]\nrepository_memberships\": [\n \"scenario_test\"\n]\n]\n]\nRequest # 7: Fetch Errata ids for repository\n\nPOST /pulp/api/v2/repositories/scenario_test/search/units/\n\nBackend Service: pulp\n\nDescription:\n\nRequest body\n\n```\n{\n \"criteria\": {\n \"type_ids\": [\"erratum\"],\n \"fields\": {\n \"unit\": [ ]\n },\n \"association\": {\n \"unit_id\": [ ]\n }\n }\n}\n```\n\nResponse body\n\n```\n[\n {\n \"metadata\": {\n \"_id\": \"4b12197f-28b0-4d5c-bf8d-057dc0b378f1\",\n \"_content_type_id\": \"erratum\"\n },\n \"id\": {\"$oid\": \"58dd7595e6919db96421ea1e\"},\n \"unit_id\": \"4b12197f-28b0-4d5c-bf8d-057dc0b378f1\",\n \"unit_type_id\": \"erratum\"\n },\n {\n \"metadata\": {\n \"_id\": \"5bc4a860-2872-461a-8061-b30626274f61\",\n \"_content_type_id\": \"erratum\"\n },\n \"id\": {\"$oid\": \"58dd7595e6919db96421ea1f\"},\n \"unit_id\": \"5bc4a860-2872-461a-8061-b30626274f61\",\n \"unit_type_id\": \"erratum\"\n },\n {\n \"metadata\": {\n \"_id\": \"c1227ae-b619-40cc-afbc-75c92e78ca13\",\n \"_content_type_id\": \"erratum\"\n },\n \"id\": {\"$oid\": \"58dd7595e6919db96421ea1d\"},\n \"unit_id\": \"c1227ae-b619-40cc-afbc-75c92e78ca13\",\n \"unit_type_id\": \"erratum\"\n }\n]\n```\n\nRequest # 8: Fetch errata units.\n\nPOST /pulp/api/v2/content/units/erratum/search/\n\nBackend Service: pulp\n\nDescription: Using the previously fetched ids, we fetch all errata in the repo.\nRequest body\n\n```json\n{\n \"criteria\": {\n \"limit\": 3,\n \"skip\": 0,\n \"filters\": {\n \"$in\": [\n \"4b12197f-28b0-4d5c-bf8d-057dc0b378f1\",\n \"5bc4a860-2872-461a-8061-b30626274615\",\n \"c12277ae-b619-40cc-afbc-75c92a78ca13\"\n ]\n }\n },\n \"include_repos\": true\n}\n```\n\nResponse body\n\n```json\n[\n {\n \"repository_memberships\": [\n \"scenario_test\"\n ],\n \"_href\": \"https://rhn.redhat.com/errata/RHSA-2010-0858.html\",\n \"issued\": \"2010-11-10 00:00:00\",\n \"references\": [\n {\n \"href\": \"https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=627882\",\n \"type\": \"bugzilla\",\n \"id\": \"627882\",\n \"title\": \"CVE-2010-0405 bzip2: integer overflow flaw in BZ2_decompress\"\n },\n {\n \"href\": \"https://www.redhat.com/security/data/cve/CVE-2010-0405.html\",\n \"type\": \"cve\",\n \"id\": \"CVE-2010-0405\",\n \"title\": \"CVE-2010-0405\"\n },\n {\n \"href\": \"http://www.redhat.com/security/updates/classification/#important\",\n \"type\": \"other\",\n \"id\": null,\n \"title\": null\n }\n ],\n \"pulp_user_metadata\": {\n \"_content_type_id\": \"erratum\",\n \"id\": \"RHSA-2010:0858\",\n \"from\": \"security@redhat.com\",\n \"severity\": \"Important\",\n \"title\": \"Important: bzip2 security update\",\n \"version\": \"3\",\n \"reboot_suggested\": false,\n \"type\": \"security\",\n \"pkglist\": [\n {\n \"_pulp_repo_id\": \"scenario_test\",\n \"packages\": [\n {\n \"src\": \"bzip2-1.0.5-7.el6_0.src.rpm\",\n \"name\": \"bzip2-devel\",\n \"sum\": {\n \"sha256\": \"ea67c664da1ff96a6dc94d33009b73d8fab31b59824183fb45e9ba2ebf82d583\"\n },\n \"filename\": \"bzip2-devel-1.0.5-7.el6_0.i686.rpm\",\n \"epoch\": 0,\n \"version\": \"1.0.5\",\n \"release\": \"7.el6_0\",\n \"arch\": \"i686\"\n },\n {\n \"src\": \"bzip2-1.0.5-7.el6_0.src.rpm\",\n \"name\": \"bzip2-libs\",\n \"sum\": {\n \"sha256\": \"c9f064a8862573fb9f2a6af7c3621f1940b492df2edfc2ebbdcc0b8305ff51147\"\n },\n \"filename\": \"bzip2-libs-1.0.5-7.el6_0.i686.rpm\",\n \"epoch\": 0,\n \"version\": \"1.0.5\",\n \"release\": \"7.el6_0\",\n \"arch\": \"i686\"\n }\n ]\n }\n ]\n }\n }\n]```\n```\n\"filename\": \"bzip2-1.0.5-7.el6_0.i686.rpm\",\n\"epoch\": \"0\",\n\"version\": \"1.0.5\",\n\"release\": \"7.el6_0\",\n\"arch\": \"i686\"\n],\n\"src\": \"bzip2-1.0.5-7.el6_0.src.rpm\",\n\"name\": \"bzip2\",\n\"sum\": {\n\"sha256\": \"b8a3f72cb2b0d89ba737099a98bfb82a4f68e02d31b884c02db97f766c3d5c2\"\n},\n\"filename\": \"bzip2-1.0.5-7.el6_0.x86_64.rpm\",\n\"epoch\": \"0\",\n\"version\": \"1.0.5\",\n\"release\": \"7.el6_0\",\n\"arch\": \"x86_64\"\n],\n\"src\": \"bzip2-1.0.5-7.el6_0.src.rpm\",\n\"name\": \"bzip2-devel\",\n\"sum\": {\n\"sha256\": \"7f63124e4655b7c92d23ec4c382265f5d3746568853df7501c85e058e74b5cf6\"\n},\n\"filename\": \"bzip2-devel-1.0.5-7.el6_0.x86_64.rpm\",\n\"epoch\": \"0\",\n\"version\": \"1.0.5\",\n\"release\": \"7.el6_0\",\n\"arch\": \"x86_64\"\n],\n\"src\": \"bzip2-1.0.5-7.el6_0.src.rpm\",\n\"name\": \"bzip2-libs\",\n\"sum\": {\n\"sha256\": \"802f4399dbdd01476e254c3b32c40a0ff59c5f23e45fa488c6917ce8904d6b4d\"\n},\n\"filename\": \"bzip2-libs-1.0.5-7.el6_0.x86_64.rpm\",\n\"epoch\": \"0\",\n\"version\": \"1.0.5\",\n\"release\": \"7.el6_0\",\n\"arch\": \"x86_64\"\n],\n\"name\": \"Red Hat Enterprise Linux Server (v. 6 for 64-bit x86_64)\",\n\"short\": \"rhel-x86_64-server-6\"\n],\n\"status\": \"final\",\n\"updated\": \"2010-11-10 00:00:00\",\n\"description\": \"bzip2 is a freely available, high-quality data compressor. It provides both libbz2 library must be restarted for the update to take effect.\",\n\"last_updated\": \"2017-03-30T21:16:05Z\",\n\"pushcount\": \"\",\n\"rights\": \"Copyright 2010 Red Hat Inc\",\n\"solution\": \"Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at http://kbase.redhat.com/faq/docs/DOC-11259\",\n\"summary\": \"Updated bzip2 packages that fix one security issue\",\n\"release\": \"\",\n\"id\": \"RHEA-2010:0002\",\n\"from\": \"lzap+pub@redhat.com\",\n\"severity\": \"\",\n\"title\": \"One package errata\",\n\"children\": []\n}]```\nRequest # 9: Fetch package group units for repository\n\nPOST /pulp/api/v2/repositories/scenario_test/search/units/\n\nBackend Service: pulp\n\nDescription:\n\nRequest body\n\n```json\n{\n \"criteria\": {\n \"type_ids\": [\n \"package_group\"\n ],\n \"fields\": {\n \"unit\": [ ]\n }\n }\n}\n```\n\nResponse body\n\n```json\n\"filename\": \"elephant-0.3-0.8.noarch.rpm\",\n\"epoch\": null,\n\"version\": \"0.3\",\n\"release\": \"0.8\",\n\"arch\": \"noarch\"\n```\nRequest # 10: Fetch package group ids for repository\n\nPOST /pulp/api/v2/content/units/package_group/search/\n\nBackend Service: pulp\n\nDescription: Using the previously fetched ids, we fetch all package groups in the repo.\n\nRequest body\n\n```json\n{\n \"criteria\": {\n \"limit\": 2,\n \"skip\": 0,\n \"filters\": {\n \"_id\": {\n \"$in\": [\n \"919baa7e-e944-4602-b3ed-3aef2ae5b509\",\n \"c55b5b16-7501-4863-8e3f-7f520bc795fd\"\n ]\n }\n }\n },\n \"include_repos\": true\n}\n```\n\nResponse body\n\n```json\n[\n {\n \"metadata\": {\n \"_id\": \"919baa7e-e944-4602-b3ed-3aef2ae5b509\",\n \"_content_type_id\": \"package_group\"\n },\n \"_id\": {\n \"$oid\": \"58dd7595e6919db96421ea21\"\n },\n \"unit_id\": \"919baa7e-e944-4602-b3ed-3aef2ae5b509\",\n \"unit_type_id\": \"package_group\"\n },\n {\n \"metadata\": {\n \"_id\": \"c55b5b16-7501-4863-8e3f-7f520bc795fd\",\n \"_content_type_id\": \"package_group\"\n },\n \"_id\": {\n \"$oid\": \"58dd7595e6919db96421ea20\"\n },\n \"unit_id\": \"c55b5b16-7501-4863-8e3f-7f520bc795fd\",\n \"unit_type_id\": \"package_group\"\n }\n]\n```\nRequest # 11: Request applicability generation for consumers bound to the repository\n\nPOST /pulp/api/v2/repositories/actions/content/regenerate_applicability/\n\nBackend Service: pulp\n\nDescription:\n\nRequest body\nResponse body\n\n```json\n{\n \"parallel\": true,\n \"repo_criteria\": {\n \"filters\": [\n {\n \"id\": {\n \"$in\": [\"scenario_test\"]\n }\n }\n ]\n }\n}\n```\n\nRequest # 12: Monitor task group status\nGET /pulp/api/v2/task_groups/b0e268a7-f4bf-4598-90a3-5fc3b562cc95/state_summary/\nBackend Service: pulp\nDescription: Monitor status of the applicability generation\nRequest body\nNone\nResponse body\n\n```json\n{\n \"accepted\": 0,\n \"finished\": 0,\n \"running\": 0,\n \"canceled\": 0,\n \"waiting\": 0,\n \"skipped\": 0,\n \"suspended\": 0,\n \"error\": 0,\n \"total\": 0\n}\n```\n\nResponse body\n\n```json\n{\n \"group_id\": \"b0e268a7-f4bf-4598-90a3-5fc3b562cc95\",\n \"_href\": \"/pulp/api/v2/task_groups/b0e268a7-f4bf-4598-90a3-5fc3b562cc95/\"\n}\n```\n\nRequest # 13: Fetch repository details\nGET /pulp/api/v2/repositories/scenario_test/\nBackend Service: pulp\nDescription: Unclear why\nRequest body\nNone\nResponse body\n\n```json\n{\n \"scratchpad\": {\n \"checksum_type\": \"sha256\"\n },\n \"display_name\": \"Scenario yum product\",\n \"description\": null,\n \"distributors\": [\n {\n \"repo_id\": \"scenario_test\",\n \"last_updated\": \"2017-03-30T21:15:43Z\",\n \"_href\": \"/pulp/api/v2/repositories/scenario_test/distributors/scenario_test_clone/\"\n },\n {\n \"last_override_config\": {},\n \"last_publish\": null,\n \"distributor_type_id\": \"yum_clone_distributor\",\n \"auto_publish\": false,\n \"scratchpad\": {},\n \"_ns\": \"repo_distributors\",\n \"_id\": {\n \"$oid\": \"58dd757f418a8a8a04f88de7da\"\n }\n }\n ]\n}\n```\n\"config\": { \n \"destination_distributor_id\": \"scenario_test_clone\" \n}, \n\"repo_id\": \"scenario_test\", \n\"last_updated\": \"2017-03-30T21:16:05Z\", \n\"_href\": \"/pulp/api/v2/repositories/scenario_test/distributors/scenario_test/\", \n\"last_overwrite_config\": { \n}, \n\"last_publish\": \"2017-03-30T21:16:05Z\", \n\"distributor_type_id\": \"yum_distributor\", \n\"auto_publish\": true, \n\"scratchpad\": { \n}, \n\"_ns\": \"repo_distributors\", \n\"_id\": { \n \"$oid\": \"58dd757f418a8a04f88de7d8\" \n}, \n\"config\": { \n \"checksum_type\": \"sha256\", \n \"protected\": true, \n \"http\": false, \n \"https\": true, \n \"relative_url\": \"scenario_test\" \n}, \n\"id\": \"scenario_test\" \n}, \n\"repo_id\": \"scenario_test\", \n\"last_updated\": \"2017-03-30T21:15:43Z\", \n\"_href\": \"/pulp/api/v2/repositories/scenario_test/distributors/export_distributor/\", \n\"last_overwrite_config\": { \n}, \n\"last_publish\": null, \n\"distributor_type_id\": \"export_distributor\", \n\"auto_publish\": false, \n\"scratchpad\": { \n}, \n\"_ns\": \"repo_distributors\", \n\"_id\": { \n \"$oid\": \"58dd757f418a8a04f88de7d9\" \n}, \n\"config\": { \n \"http\": false, \n \"https\": false, \n \"relative_url\": \"scenario_test\" \n}, \n\"id\": \"export_distributor\" \n], \n\"last_unit_added\": \"2017-03-30T21:16:05Z\", \n\"notes\": { \n \"repo-type\": \"rpm-repo\" \n}, \n\"last_unit_removed\": null, \n\"content_unit_counts\": { \n \"package_group\": 2, \n \"distribution\": 1, \n \"package_category\": 1, \n \"rpm\": 8, \n \"erratum\": 3 \n}, \n\"_ns\": \"repos\", \n\"importers\": [ \n{ \n \"repo_id\": \"scenario_test\", \n \"last_updated\": \"2017-03-30T21:15:43Z\", \n \"_href\": \"/pulp/api/v2/repositories/scenario_test/importers/yum_importer/\", \n \"_ns\": \"repo_importers\", \n \"importer_type_id\": \"yum_importer\" \n}, \n\"_id\": { \n \"$oid\": \"58dd757f418a8a04f88de7d7\" \n}, \n\"config\": { \n \"feed\": \"file:///var/www/test_repos/zoo\", \n \"ssl_validation\": true, \n \"remove_missing\": true, \n \"download_policy\": \"immediate\" \n}, \n\"id\": \"yum_importer\" \n}, \n\"locally_stored_units\": 15,\nRepository Create\n\nRequest # 1: Create Content\n\nPOST /candlepin/owners/scenario_test/content/\n\nBackend Service: candlepin\n\nDescription: Create Content object for repository, for subscription-manager content access\n\nRequest body\n\n```json\n{\n \"name\": \"Scenario yum product\",\n \"contentUrl\": \"/custom/Scenario_Product/Scenario_yum_product\",\n \"type\": \"yum\",\n \"label\": \"scenario_test_Scenario_Product_Scenario_yum_product\",\n \"metadataExpire\": 1,\n \"vendor\": \"Custom\"\n}\n```\n\nResponse body\n\n```json\n{\n \"created\": \"2017-03-30T21:15:43+0000\",\n \"updated\": \"2017-03-30T21:15:43+0000\",\n \"uuid\": \"4028f9515b20f31e015b2112fba4000d\",\n \"id\": \"1490908543901\",\n \"type\": \"yum\",\n \"label\": \"scenario_test_Scenario_Product_Scenario_yum_product\",\n \"name\": \"Scenario yum product\",\n \"vendor\": \"Custom\",\n \"contentUrl\": \"/custom/Scenario_Product/Scenario_yum_product\",\n \"requiredTags\": null,\n \"gpgUrl\": null,\n \"metadataExpire\": 1,\n \"modifiedProductIds\": [],\n \"arches\": null,\n \"releaseVer\": null\n}\n```\n\nRequest # 2: Associate content object\n\nPOST /candlepin/owners/scenario_test/products/272869743822/content/1490908543901\n\nBackend Service: candlepin\n\nDescription: Add the Content object to the product\n\nRequest body\n\nNone\n\nResponse body\nRequest # 3: Retrieve candlepin environment\n\nGET /candlepin/environments/119c4753ff6d3b7bd0b76de6d5a5f94a\n\nBackend Service: candlepin\n\nDescription: Retrieve the environment object (TODO WHY?)\n\nRequest body\n\nNone\n\nResponse body\n\n```json\n{\n \"owner\": {\n \"id\": \"4028f9515b2031e015b2112fc03000e\",\n \"key\": \"scenario_test\",\n \"displayName\": \"scenario_test\",\n \"href\": \"/owners/scenario_test\"\n },\n \"name\": \"Library\",\n \"description\": null,\n \"id\": \"119c4753ff6d3b7bd0b76de6d5a5f94a\",\n \"environmentContent\": {\n \"created\": \"2017-03-30T21:15:41+0000\",\n \"updated\": \"2017-03-30T21:15:41+0000\"\n }\n}\n```\n\nRequest # 4: Create Pulp Repository\n\nPOST /pulp/api/v2/repositories/\n\nBackend Service: pulp\n\nDescription:\n\n```json\n{\n \"created\": \"2017-03-30T21:15:42+0000\",\n \"updated\": \"2017-03-30T21:15:44+0000\",\n \"uuid\": \"4028f9515b2031e015b2112fc03000e\",\n \"id\": \"27269743822\",\n \"name\": \"Scenario Product\",\n \"multiplier\": 1,\n \"attributes\": {\n \"created\": \"2017-03-30T21:15:42+0000\",\n \"updated\": \"2017-03-30T21:15:44+0000\",\n \"name\": \"arch\",\n \"value\": \"ALL\"\n },\n \"dependentProductIds\": [],\n \"href\": \"/products/4028f9515b2031e015b2112fc03000e\",\n \"productContent\": [\n {\n \"created\": \"2017-03-30T21:15:43+0000\",\n \"updated\": \"2017-03-30T21:15:43+0000\",\n \"uuid\": \"4028f9515b2031e015b2112b40000d\",\n \"id\": \"149000545891\",\n \"type\": \"yum\",\n \"name\": \"Scenario yum product\",\n \"vendor\": \"Custom\",\n \"contentUrl\": \"/custom/Scenario_Product/Scenario_yum_product\",\n \"requiredTags\": null,\n \"gpgUrl\": null,\n \"metadataExpire\": 1,\n \"modifiedProductIds\": [],\n \"arches\": null,\n \"releaseVer\": null,\n \"enabled\": true\n }\n ],\n \"owner\": {\n \"id\": \"4028f9515b2031e015b21122550004\",\n \"key\": \"scenario_test\",\n \"displayName\": \"scenario_test\",\n \"href\": \"/owners/scenario_test\"\n },\n \"name\": \"Library\",\n \"description\": null,\n \"id\": \"119c4753ff6d3b7bd0b76de6d5a5f94a\",\n \"environmentContent\": {\n \"created\": \"2017-03-30T21:15:41+0000\",\n \"updated\": \"2017-03-30T21:15:41+0000\"\n }\n}\n```\nRequest body\n\n```\n{\n \"id\": \"scenario_test\",\n \"display_name\": \"Scenario yum product\",\n \"importer_type_id\": \"yum_importer\",\n \"importer_config\": {\n \"feed\": \"file:///var/www/test_repos/zoo\",\n \"ssl_ca_cert\": null,\n \"ssl_client_cert\": null,\n \"ssl_client_key\": null,\n \"ssl_validation\": true,\n \"download_policy\": \"immediate\",\n \"remove_missing\": true\n },\n \"notes\": {\n \"_repo-type\": \"rpm-repo\"\n },\n \"distributors\": [\n {\n \"distributor_type_id\": \"yum_distributor\",\n \"distributor_config\": {\n \"relative_url\": \"scenario_test\",\n \"http\": false,\n \"https\": true,\n \"protected\": true\n },\n \"auto_publish\": true,\n \"distributor_id\": \"scenario_test\"\n },\n {\n \"distributor_type_id\": \"export_distributor\",\n \"distributor_config\": {\n \"http\": false,\n \"https\": false\n },\n \"auto_publish\": false,\n \"distributor_id\": \"export_distributor\"\n },\n {\n \"distributor_type_id\": \"yum_clone_distributor\",\n \"distributor_config\": {\n \"destination_distributor_id\": \"scenario_test\"\n },\n \"auto_publish\": false,\n \"distributor_id\": \"scenario_test_clone\"\n }\n ]\n}\n```\n\nResponse body\n\n```\n{\n \"scratchpad\": {\n \"display_name\": \"Scenario yum product\",\n \"description\": null,\n \"last_unit_added\": null,\n \"notes\": {\n \"_repo-type\": \"rpm-repo\"\n },\n \"last_unit_removed\": null,\n \"content_unit_counts\": {\n \"_ns\": \"repos\",\n \"_id\": {\n \"$oid\": \"58dd757f418a8a04f88de7d6\"\n },\n \"id\": \"scenario_test\",\n \"_href\": \"/pulp/api/v2/repositories/scenario_test/\"\n }\n }\n}\n```\n\nRequest # 5: Add Content To environment\n\nPOST /candlepin/environments/119c4753ff6d3b7bd0b76de6d5a5f94a/content\n\nBackend Service: candlepin\n\nDescription: Associates content object to “Library” environment, so it is accessible by clients registered to Library\n\nRequest body\nRequest # 6: Fetch repository information\n\nGET /pulp/api/v2/repositories/scenario_test/\n\nBackend Service: pulp\n\nDescription:\n\nRequest body\n\nNone\n\nResponse body\n\n```json\n{\n \"contentId\": \"1490908543901\"\n}\n```\nRequest # 7: Publish repository metadata\n\nPOST /pulp/api/v2/repositories/scenario_test/actions/publish/\n\nBackend Service: pulp\n\nDescription: Publish the repository, generating empty metadata so that existing clients of that product do not get a 404.\n\nRequest body\n\n```\n{\n \"id\": \"scenario_test\",\n \"override_config\": {\n \"force_full\": false\n }\n}\n```\n\nResponse body\nRequest # 8: Poll Task\n\nGET /pulp/api/v2/tasks/dfdb7cae-e465-4885-b3a4-7bb29343b69e/\n\nBackend Service: pulp\n\nDescription: Monitor the task status of the publish\n\nTotal Requests for this URL: 6\n\nRequest body\nNone\n\nResponse body\n\n```json\n{\n \"exception\": null,\n \"task_type\": \"pulp.server.managers.repo.publish.publish\",\n \"_href\": \"/pulp/api/v2/tasks/dfdb7cae-e465-4885-b3a4-7bb29343b69e/\",\n \"task_id\": \"dfdb7cae-e465-4885-b3a4-7bb29343b69e\",\n \"tags\": [\n \"pulp:repository:scenario_test\",\n \"pulp:action:publish\"\n ],\n \"finish_time\": \"2017-03-30T21:15:44Z\",\n \"_ns\": \"task_status\",\n \"start_time\": \"2017-03-30T21:15:44Z\",\n \"traceback\": null,\n \"spawned_tasks\": []\n}\n```\n\n```json\n{ \"progress_report\": { \"scenario_test\": [ { \"num_success\": 1, \"description\": \"initializing repo metadata\", \"step_type\": \"initialize_repo_metadata\", \"items_total\": 1, \"state\": \"FINISHED\", \"error_details\": [ ] }, { \"details\": \"\", \"num_failures\": 0, \"step_id\": \"e3a30d24-1111-4080-92f8-0a3dc979ae9c\", \"num_processed\": 1 } ] }, { \"num_success\": 0, \"description\": \"Publishing Distribution files\", \"step_type\": \"distribution\", \"items_total\": 0, \"state\": \"FINISHED\", \"error_details\": [ ] }, { \"details\": \"\", \"num_failures\": 0, \"step_id\": \"c2edbc90-716d-4570-a442-bd0c22748188\", \"num_processed\": 0 } ] }, { \"num_success\": 0, \"description\": \"Publishing RPMs\", \"step_type\": \"rpms\", \"items_total\": 0, \"state\": \"FINISHED\", \"error_details\": [ ] }, { \"details\": \"\", \"num_failures\": 0, \"step_id\": \"bfeaa715-21d9-4cf0-af2a-5c5e0c1c172b\", \"num_processed\": 0 } ] }\n```\n\"num_success\": 0,\n\"description\": \"Publishing Delta RPMs\",\n\"step_type\": \"drpms\",\n\"items_total\": 1,\n\"state\": \"SKIPPED\",\n\"error_details\": [\n\n],\n\"details\": \"\",\n\"num_failures\": 0,\n\"step_id\": \"47621356-70b3-4e77-a8f2-ee1ec0c5c2ee\",\n\"num_processed\": 0\n],\n\n\"num_success\": 0,\n\"description\": \"Publishing Errata\",\n\"step_type\": \"errata\",\n\"items_total\": 0,\n\"state\": \"FINISHED\",\n\"error_details\": [\n\n],\n\"details\": \"\",\n\"num_failures\": 0,\n\"step_id\": \"8e46b5e2-89f5-4ef5-80bd-0d2aab9dd2a0\",\n\"num_processed\": 0\n],\n\n\"num_success\": 0,\n\"description\": \"Publishing Comps file\",\n\"step_type\": \"comps\",\n\"items_total\": 0,\n\"state\": \"FINISHED\",\n\"error_details\": [\n\n],\n\"details\": \"\",\n\"num_failures\": 0,\n\"step_id\": \"050aba89-abec-4949-b3cf-28409d9519e0\",\n\"num_processed\": 0\n],\n\n\"num_success\": 0,\n\"description\": \"Publishing Metadata.\",\n\"step_type\": \"metadata\",\n\"items_total\": 0,\n\"state\": \"FINISHED\",\n\"error_details\": [\n\n],\n\"details\": \"\",\n\"num_failures\": 0,\n\"step_id\": \"70efd383-905d-4fe2-8c9b-4e18311e76d5\",\n\"num_processed\": 0\n],\n\n\"num_success\": 1,\n\"description\": \"Closing repo metadata\",\n\"step_type\": \"close_repo_data\",\n\"items_total\": 1,\n\"state\": \"FINISHED\",\n\"error_details\": [\n\n],\n\"details\": \"\",\n\"num_failures\": 0,\n\"step_id\": \"e3ae5910-8f8d-4e53-abd6-007a9495e0b4\",\n\"num_processed\": 1\n],\n\n\"num_success\": 0,\n\"description\": \"Generating sqlite files\",\n\"step_type\": \"generate_sqlite\",\n\"items_total\": 1,\n\"state\": \"SKIPPED\",\n\"error_details\": [\n\n],\n\"details\": \"\",\n\"num_failures\": 0,\n\"step_id\": \"ae023865-a176-4434-b8ab-77a080306602\",\n\"num_processed\": 0\n],\n\n\"num_success\": 0,\n\"description\": \"Generating HTML files\",\n\"step_type\": \"repoview\",\n\"items_total\": 1,\n\"state\": \"SKIPPED\",\n\"error_details\": [\n\n],\n\"details\": \"\",\n\"num_failures\": 0,\n\"step_id\": \"9e023865-a176-4434-b8ab-77a080306602\",\n\"num_processed\": 0\n]\nnull\n\"num_failures\": 0,\n\"step_id\": \"4d7ca329-7b33-478e-a0a5-777771d8c7c6\",\n\"num_processed\": 0\n],\n\n\"num_success\": 1,\n\"description\": \"Publishing files to web\",\n\"step_type\": \"publish_directory\",\n\"items_total\": 1,\n\"state\": \"FINISHED\",\n\"error_details\": []\n],\n\ndetails\": \n\"num_failures\": 0,\n\"step_id\": \"0986744f-85dc-43ff-9e0f-10c814a8d5e8\",\n\"num_processed\": 1\n],\n\n\"num_success\": 1,\n\"description\": \"Writing Listings File\",\n\"step_type\": \"initialize_repo_metadata\",\n\"items_total\": 1,\n\"state\": \"FINISHED\",\n\"error_details\": []\n],\n\ndetails\": \n\"num_failures\": 0,\n\"step_id\": \"04b588ee-11fe-4b09-8a42-2ea465247c0b\",\n\"num_processed\": 1\n],\n\nnull\n\"result\": \n\"result\": \"success\",\n\"exception\": null,\n\"repo_id\": \"scenario_test\",\n\"started\": \"2017-03-30T21:15:44Z\",\n\"ns\": \"repo_publish_results\",\n\"updated\": \"2017-03-30T21:15:44Z\",\n\"traceback\": null,\n\"distributor_type_id\": \"yum_distributor\",\n\"summary\": \n\"generate sqlite\": \"SKIPPED\",\n\"initialize_repo_metadata\": \"FINISHED\",\n\"rpms\": \"FINISHED\",\n\"close_repo_metadata\": \"FINISHED\",\n\"drpms\": \"SKIPPED\",\n\"comps\": \"FINISHED\",\n\"distribution\": \"FINISHED\",\n\"repopview\": \"SKIPPED\",\n\"publish_directory\": \"FINISHED\",\n\"errata\": \"FINISHED\",\n\"metadata\": \"FINISHED\"\n],\n\"error_message\": null,\n\"distributor_id\": \"scenario_test\",\n\"id\": \"58dd7580418a8a0648b9bc40\",\n\"details\": []\n]\n<table>\n<thead>\n<tr>\n<th>ID</th>\n<th>Step Type</th>\n<th>Step Details</th>\n<th>Items Total</th>\n<th>State</th>\n<th>Error Details</th>\n<th>Num Failures</th>\n<th>Num Success</th>\n<th>Details</th>\n<th>Num Processed</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>rpms</td>\n<td>Publishing RPMs</td>\n<td>0</td>\n<td>FINISHED</td>\n<td></td>\n<td>0</td>\n<td>0</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>2</td>\n<td>drpms</td>\n<td>Publishing Delta RPMs</td>\n<td>1</td>\n<td>SKIPPED</td>\n<td></td>\n<td>0</td>\n<td>0</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>3</td>\n<td>errata</td>\n<td>Publishing Errata</td>\n<td>0</td>\n<td>FINISHED</td>\n<td></td>\n<td>0</td>\n<td>0</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>4</td>\n<td>comps</td>\n<td>Publishing Comps file</td>\n<td>0</td>\n<td>FINISHED</td>\n<td></td>\n<td>0</td>\n<td>0</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>5</td>\n<td>metadata</td>\n<td>Publishing Metadata</td>\n<td>0</td>\n<td>FINISHED</td>\n<td></td>\n<td>0</td>\n<td>0</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>6</td>\n<td>close_repo_metadata</td>\n<td>Closing repo metadata</td>\n<td>1</td>\n<td>FINISHED</td>\n<td></td>\n<td>0</td>\n<td>1</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>7</td>\n<td>generate_sqlite</td>\n<td>Generating sqlite files</td>\n<td>1</td>\n<td>SKIPPED</td>\n<td></td>\n<td>0</td>\n<td>0</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>"}}},{"rowIdx":57,"cells":{"id":{"kind":"string","value":"f23939285f7fc738ee396f92f0404cb71b894898"},"text":{"kind":"string","value":"Specification Platform for Library IP Development\nJung Kyu Chae\n\nTo cite this version:\n\nHAL Id: tel-01126920\nhttps://tel.archives-ouvertes.fr/tel-01126920\nSubmitted on 6 Mar 2015\n\nHAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.\n\nL’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.\nPlateforme de spécification pour le développement de bibliothèques de cellules et d’IPs\n\nPar Jung Kyu CHAE\n\nThèse de doctorat d’informatique\n\nDirigée par Habib MEHREZ et Roselyne CHOTIN-AVOT\n\nPrésentée et soutenue publiquement le 9 Juillet 2014\nAcknowledgements\n\nI would like to express my gratitude, appreciation and sincere thanks to my supervisors Prof. Habib MEHREZ and Assoc. Prof. Roselyne CHOTIN-AVOT for their excellent guidance, helpful and useful discussions, and continuous encouragement.\n\nI would like to express my thanks to my ST supervisor Dr. Jean-Arnaud François for giving me the opportunity to carry out my thesis within Central CAD & Design Solutions Department at STMicroelectronics. Moreover, I also sincerely thank him for his support, guidance, encouragement and advice.\n\nI am really grateful to Paul MOUGEAT, who provided valuable expertise, insightful comments and constructive critiques. His cool personality and sense of humor always inspired me. I have learnt a lot from him.\n\nI wish to express my deepest gratitude to Dr. Marc QUAST for the helpful and valuable discussions, constructive remarks and encouragement which helped me carry out the PhD thesis work in an efficient manner.\n\nI am especially grateful to my colleagues Severine BERTRAND, Sylvain LANDELLE, Pierre-Francois OLLAGNONG, Syed Shahkar KAKAKHAIL, Brice SERVAIS, Frederic ESTEBAN, Lahcen HAMOUCHE, Sophie RABADAN, Lionel MAIAUX, Pierre MONNOT, Aymen ALBOUCHI, Christophe BOURELY, Sami ABBADI, Mohamed Karim KSONTINI and Arnaud MAGRY for their support both in terms of resources and encouragement.\n\nMy special thanks go to my family members who have been extremely understanding and supportive of my studies. This thesis is dedicated to my parents.\nAbstract\n\nA design platform (DP) is a total solution to build a System-On-Chip (SOC). DP consists of a set of libraries/IPs, CAD tools and design kits in conformity with the supported design flows and methodologies. The DP specifications provide a wide range of information from technology parameters like Process-Voltage-Temperature (PVT) corners to CAD tools’ information for library/IP development. However, the library/IP developers have difficulties in obtaining the desired data from the existing specifications due to their informality and complexity.\n\nIn this thesis, we propose methodologies, flows and tools to formalize the DP specifications for their unification and to deal with it. The proposed description is targeting to be used as a reference to generate and validate libraries (standard cells, I/O, memory) as well as complex IPs (PLL, Serdes, etc.).\n\nFirst, we build a data model to represent all required information for library/IP development and then propose a specification language named Library Development Specification based on XML (LDSpecX). Furthermore, we introduce a reference-based method to create a reliable specification in LDSpecX and task-based keywords to efficiently extract data from it. On the basis of the proposed solutions, we develop a specification platform. This platform allows not only creating a complete and consistent specification with a huge amount of data but also rapidly and precisely extracting data depending on the task.\n\nWe develop a standard cell library from the specification creation to library validation by using the specification platform. We show that our approach enables to create a complete and consistent specification with a considerable reduction in time. It also bridges the gap between the specification and current automatic system for rapid library/IP development.\n\nKeywords: Design Platform, Design Methodology, Unified specification, Library/IP development, Specification creation, Data extraction\nRésumé\n\nUne plateforme de conception est une solution totale qui permet à une équipe de conception de développer un système sur puce. Une telle plateforme se compose d’un ensemble de bibliothèques et de circuits réutilisables (IPs), d’outils de CAO et de kits de conception en conformité avec les flots de conception et les méthodologies supportés. Les spécifications de ce type de plateforme offrent un large éventail d’informations, depuis des paramètres de technologie, jusqu’aux informations sur les outils de CAO pour le développement des bibliothèques/IPs. En outre, les développeurs de bibliothèque/IP ont des difficultés à obtenir les données nécessaires à partir des spécifications existantes en raison du fait qu’elles ne soient pas formellement spécifiées et de leur complexité.\n\nDans cette thèse, nous proposons des méthodologies, des flots et des outils pour formaliser les spécifications d’une plateforme de conception pour leurs unification et les traiter. Cette description proposée vise à être utilisée comme une référence pour générer et valider les bibliothèques (cellules standard, entrée/sortie et mémoire) ainsi que les IPs complexes (PLL, Serdes, etc.).\n\nPremièrement, nous construisons un modèle de données pour représenter toutes les informations nécessaires pour le développement de bibliothèques et proposons un langage de spécification pour le développement de bibliothèques basé sur XML (LDSpecX). De plus, nous présentons une méthode basée sur des références pour créer une spécification fiable en LDSpecX et des mots-clés basés sur des tâches pour en extraire les données. A l’aide des solutions proposées, nous développons une plateforme de spécification qui fournit une interface utilisateur graphique (GUI) et une interface de programmation (API). Cette plateforme permet non seulement la création de la spécification, mais aussi l’extraction rapide des données en fonction de la tâche.\n\nNous développons une bibliothèque de cellules standard depuis la création de la spécification jusqu’à la validation de la bibliothèque en utilisant cette plateforme de spécification. Nous montrons ainsi que notre approche permet de créer une spécification complète et cohérente avec une réduction considérable du temps. Cette proposition comble également l’écart entre les spécifications et le système automatique existant pour le développement rapide de bibliothèques/IPs.\nMots-clés : Plateforme de conception, Méthodologie de conception, Spécification unifiée, Développement des bibliothèques/IPs, Création de la spécification, Extraction des données\nTable of Contents\n\n1. Introduction ........................................................................................................... 1\n 1.1 Motivation ........................................................................................................ 3\n 1.2 Thesis Objectives ............................................................................................. 4\n 1.3 Structure of this Manuscript ............................................................................. 5\n\n2. Library Development from the Design Platform Specifications .................. 7\n 2.1 Introduction ................................................................................................. 7\n 2.2 System-on-Chip Design Flow ...................................................................... 8\n 2.3 Design Platform .......................................................................................... 11\n 2.4 Library Development Flow .......................................................................... 12\n 2.4.1 Specification Phase .............................................................................. 14\n 2.4.2 Design Phase ....................................................................................... 15\n 2.4.3 Derivation Phase .................................................................................. 16\n 2.4.4 Validation Phase .................................................................................. 17\n 2.5 Existing Automatic System for Library Development ............................... 17\n 2.5.1 Specification Creation Tools .................................................................. 19\n 2.5.2 Circuit Design Tools ........................................................................... 19\n 2.5.3 View Derivation Tool .......................................................................... 20\n 2.5.4 Library Verification Tool ...................................................................... 22\n 2.6 Example of the Development of a Standard-cell Library .......................... 22\n 2.7 Problems ....................................................................................................... 25\n 2.8 Conclusion ..................................................................................................... 27\n\n3. State-of-the-art .................................................................................................... 28\n 3.1 Introduction ................................................................................................. 28\n 3.2 Natural Language-based Specification ....................................................... 29\n 3.3 Table-based Specification .......................................................................... 29\n 3.3.1 System Requirements Specification in SCR ...................................... 30\n 3.3.2 ADeVA ................................................................................................. 32\n 3.4 UML-based Specification .......................................................................... 34\n 3.5 XML-based Specification .......................................................................... 36\n 3.5.1 IP-XACT for Digital IPs ..................................................................... 37\n 3.5.2 ASDeX for Analog IPs ....................................................................... 39\n 3.6 STMicroelectronics’ Design Platform Specifications ............................... 41\n 3.7 Discussion ..................................................................................................... 42\n 3.8 Conclusion ..................................................................................................... 43\n\n4. Methodology for Library Development Specifications .................................. 44\n 4.1 Introduction ................................................................................................. 44\n 4.2 Formalism of the Specification .................................................................... 45\n 4.2.1 Requirements of the Specification ...................................................... 45\n 4.2.2 Specification Data Analysis ................................................................. 46\n 4.2.3 Specification Data Classification ......................................................... 50\n 4.2.4 Specification Data Modeling ............................................................... 54\n 4.3 Reliable Specification Creation Method ....................................................... 60\n 4.3.1 Reference Database ............................................................................ 60\n 4.3.2 Specification Creation using a Reference Database ........................... 63\n 4.4 Efficient Method for Data Extraction from the Specification .................... 63\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>4.4.1</td>\n<td>Keyword for Precise Data Identification</td>\n</tr>\n<tr>\n<td>4.4.2</td>\n<td>Task-based Keywords for Efficient Data Extraction</td>\n</tr>\n<tr>\n<td>4.5</td>\n<td>Validation of the Specification</td>\n</tr>\n<tr>\n<td>4.6</td>\n<td>Validation of the Library against the Specification</td>\n</tr>\n<tr>\n<td>4.7</td>\n<td>Conclusion</td>\n</tr>\n<tr>\n<td>5.1</td>\n<td>Introduction</td>\n</tr>\n<tr>\n<td>5.2</td>\n<td>LDSpecX: Library Development Specification based on XML</td>\n</tr>\n<tr>\n<td>5.3</td>\n<td>Specification Creation Tool</td>\n</tr>\n<tr>\n<td>5.3.1</td>\n<td>XML-based Reference Database</td>\n</tr>\n<tr>\n<td>5.3.2</td>\n<td>User-friendly GUI for Specification Creation</td>\n</tr>\n<tr>\n<td>5.4</td>\n<td>API for Specification Data Extraction</td>\n</tr>\n<tr>\n<td>5.4.1</td>\n<td>Library Development Task Definition</td>\n</tr>\n<tr>\n<td>5.4.2</td>\n<td>Specification Data API</td>\n</tr>\n<tr>\n<td>5.4.3</td>\n<td>Library Verification Tool using the API</td>\n</tr>\n<tr>\n<td>5.5</td>\n<td>Conclusion</td>\n</tr>\n<tr>\n<td>5.6</td>\n<td>Specification Platform</td>\n</tr>\n<tr>\n<td>5.7</td>\n<td>Introduction</td>\n</tr>\n<tr>\n<td>5.8</td>\n<td>LDSpecX: Library Development Specification based on XML</td>\n</tr>\n<tr>\n<td>5.9</td>\n<td>Specification Creation Tool</td>\n</tr>\n<tr>\n<td>5.9.1</td>\n<td>XML-based Reference Database</td>\n</tr>\n<tr>\n<td>5.9.2</td>\n<td>User-friendly GUI for Specification Creation</td>\n</tr>\n<tr>\n<td>5.9.3</td>\n<td>API for Specification Data Extraction</td>\n</tr>\n<tr>\n<td>5.9.4</td>\n<td>Library Development Task Definition</td>\n</tr>\n<tr>\n<td>5.9.5</td>\n<td>Specification Data API</td>\n</tr>\n<tr>\n<td>5.9.6</td>\n<td>Library Verification Tool using the API</td>\n</tr>\n<tr>\n<td>5.9.7</td>\n<td>Conclusion</td>\n</tr>\n<tr>\n<td>6.1</td>\n<td>Introduction</td>\n</tr>\n<tr>\n<td>6.2</td>\n<td>Library Development from the Specification</td>\n</tr>\n<tr>\n<td>6.2.1</td>\n<td>Specification Creation</td>\n</tr>\n<tr>\n<td>6.2.2</td>\n<td>Library Development from the Specification</td>\n</tr>\n<tr>\n<td>6.3</td>\n<td>Evaluation</td>\n</tr>\n<tr>\n<td>6.3.1</td>\n<td>Specification Evaluation against Five Requirements</td>\n</tr>\n<tr>\n<td>6.3.2</td>\n<td>Specification Data Processing</td>\n</tr>\n<tr>\n<td>6.4</td>\n<td>Conclusion</td>\n</tr>\n<tr>\n<td>7.1</td>\n<td>Conclusion</td>\n</tr>\n<tr>\n<td>7.2</td>\n<td>Perspectives</td>\n</tr>\n</tbody>\n</table>\n\n**Bibliography**\n\n**Publications**\n\n**Résumé**\nList of Figures\n\nFigure 1.1 Product Technology Trends: MPU Product Functions/Chip and Industry Average “Moore’s Law” and Chip Size Trends (source: ITRS) .............................................................. 1\nFigure 1.2 ‘Moore’s law’ and ‘More than Moore’ trends in the semi-conductor industry (source: ITRS) ........................................................................................................................................ 2\nFigure 2.1 Example of a SoC (source: ST) ................................................................................ 9\nFigure 2.2 Cell-based design flow ............................................................................................ 10\nFigure 2.3 Design platform ...................................................................................................... 11\nFigure 2.4 Foundry’s library development flow (source: ST) ................................................. 12\nFigure 2.5 PVT corners for standard cell library (source: ST) ................................................ 13\nFigure 2.6 Design platform specifications vs. library development specification (source: ST) .................................................................................................................................................. 14\nFigure 2.7 Environmental considerations for library development [41] .................................. 14\nFigure 2.8 Layout development flow with manual layout [42] ................................................ 15\nFigure 2.9 Overview of P2Lib [70] ........................................................................................ 18\nFigure 2.10 Overview of an automatic library development system (source: ST) ................. 18\nFigure 2.11 Maximum capacitance (source: ST) ..................................................................... 19\nFigure 2.12 Cell characterization ............................................................................................. 20\nFigure 2.13 LEF generation methods (source: ST) .................................................................. 21\nFigure 2.14 Methodology of the transformation between Cadence OA and Synopsys MW databases [59] .......................................................................................................................... 22\nFigure 2.15 Schematic of a 4-bit Flip-Flop Bank .................................................................... 23\nFigure 3.1 The cruise control system in SCR [88] ................................................................... 30\nFigure 3.2 Mode transition table defining the mode class mcCruise [88] ............................... 31\nFigure 3.3 Variable dictionary table for the CCS [88] ............................................................ 31\nFigure 3.4 SpecEdit GUI [89] .................................................................................................. 32\nFigure 3.5 Example of MTT [89] ............................................................................................. 33\nFigure 3.6 Example of DTT [89] ............................................................................................. 33\nFigure 3.7 Dependency graph tool for the CCS [88] ............................................................... 34\nFigure 3.8 Taxonomy of structure and behavior diagrams [112] ........................................... 34\nFigure 3.9 Specification based verification process [93] ......................................................... 35\nFigure 3.10 UML class diagram [94] ....................................................................................... 35\nFigure 3.11 UML sequence diagram [94] .............................................................................. 36\nFigure 3.12 IP-XACT data object interactions [98] ................................................................. 37\nFigure 3.13 IP-XACT design environment [98] ..................................................................... 38\nFigure 3.14 Schema of ASDeX [104] .................................................................................... 39\nFigure 3.15 ASDeX data object interactions [104] ................................................................. 40\nFigure 3.16 Validation work flow based on ASDeX [104] ....................................................... 40\nFigure 3.17 STMicroelectronics’ design platform specifications (source: ST) .................... 41\nFigure 4.1 Automatic library development system (source: ST) ............................................ 46\nFigure 4.2 A task for library development (source: ST) .......................................................... 47\nFigure 4.3 Timing characterization of a non-scan D flip-flop (source: ST) ......................... 48\nFigure 4.4 Tool input data analysis results (source: ST) ......................................................... 49\nFigure 4.5 Specification data taxonomy ............................................................................... 50\nFigure 4.6 Specification data objects and their reference relationship ................................. 54\nFigure 4.7 Basic data model of the data object ................................................................. 55\nFigure 4.8 Examples of (a) non-subcategorized parameter set (b) sub-categorized parameter set ............................................................................................................................................. 55\nFigure 4.9 Examples of (a) parameter without key attribute (b) parameter with key attribute 56\nFigure 4.10 Data model of the specification ............................................................................................................. 59\nFigure 4.11 Dictionary ............................................................................................................................................. 61\nFigure 4.12 List reference ........................................................................................................................................ 61\nFigure 4.13 Tool list reference ................................................................................................................................ 62\nFigure 4.14 Specification creation using a reference database .................................................................................. 63\nFigure 4.15 Data extraction with keyword ............................................................................................................ 65\nFigure 4.16 (a) simple tool versioning with numerical increment (b) simple tool versioning with numerical and alphabetical increments (c) complex tool versioning ............................................................................. 68\nFigure 5.1 Schema of LDSpecX ............................................................................................................................ 72\nFigure 5.2 Schema of GeneralTechParams element ............................................................................................ 73\nFigure 5.3 Example of GeneralTechParams element ............................................................................................ 73\nFigure 5.4 Schema of dictionary ........................................................................................................................... 74\nFigure 5.5 Example of a dictionary ........................................................................................................................ 75\nFigure 5.6 Schema of tool list reference ................................................................................................................ 75\nFigure 5.7 Example of a tool list reference ............................................................................................................. 75\nFigure 5.8 Reference-based specification creation flow .......................................................................................... 76\nFigure 5.9 (a) Specification information entry window (b) Fragment selection window .................................... 78\nFigure 5.10 Data entry page of GeneralTechParams fragment ............................................................................... 79\nFigure 5.11 Data entry page of Tool List fragment ................................................................................................. 80\nFigure 5.12 Specification creation page ................................................................................................................ 81\nFigure 5.13 Dictionary edit page ............................................................................................................................ 82\nFigure 5.14 (a) Library development flow (b) Task .................................................................................................. 83\nFigure 5.15 Example of a library development flow for standard cell library ....................................................... 84\nFigure 5.16 Overview of the API .......................................................................................................................... 84\nFigure 5.17 Data extraction flow by using task-based keywords ............................................................................. 85\nFigure 6.1 Screenshot of specification check report ............................................................................................... 89\nFigure 7.1 Overview of the specification platform ................................................................................................. 100\nList of Tables\n\nTable 3.1: Summary of the specifications .............................................................................. 42\nTable 4.1: Specification data ................................................................................................. 53\nTable 4.2: Library checklist ................................................................................................... 68\nTable 6.1: Comparison of LDSpecX-based specification and traditional specifications...... 91\nTable 6.2: Summary of input and output for library development tasks ............................... 92\n1. **Introduction**\n\n**Contents**\n\n1.1 Motivation ................................................................................................................... 3 \n1.2 Thesis Objectives ......................................................................................................... 4 \n1.3 Structure of this Manuscript ........................................................................................ 5\n\nGordon E. Moore presented the well-known Moore’s law in an article published in 1965 [1]. This law describes a trend that the number of transistors on a chip doubles every 24 months. Until now, the development of new process technologies enables to follow Moore’s law as shown in Figure 1.1 [2]. In addition to the increasing number of transistors on a chip, the performance of System-on-Chip (SoC) (speed, functionality, etc.) considerably increases but the cost decreases by 30% per year [3].\n\n\nRecently, a new trend called “More than Moore” for the functional diversification of semiconductor-based devices is also remarked. This “More than Moore” trend gives more possibilities to diversify the applications of SoC by interacting with the outside world through an appropriate transduction such as RF communication, passive component, sensor and actuators [4]. The International Technology Roadmap for Semiconductors (ITRS) represents the overview of these two trends toward the miniaturization and diversification as described in Figure 1.2. These trends allow various applications of SoC such as automotive, set-top box and telecommunication so that the market is growing rapidly [3].\n\nFigure 1.2 ‘Moore’s law’ and ‘More than Moore’ trends in the semi-conductor industry (source: ITRS)\n\nHowever, there are more and more challenges with the new advanced technologies in the manufacturing process, circuit design, system design, and CAD technology [5]. In the manufacturing process, to achieve the downscaling of the devices, both front- and back-end processing must overcome major technological challenges: lithography, device isolation, gate stack, shallow junctions, device engineering, high- and low-k dielectrics, and interconnect schemes [6], [7], [8]. For circuit design, technology scaling brings some advantages such as high speed and density of integration. Nevertheless, circuit designers have to face significant issues such as increased leakage, variability, reducing power supply voltage, signal integrity problems, etc. Some of these issues were never encountered before. In addition, new types of devices and new materials may increase the complexity of the circuit design [9], [10], [11],\n[12]. To illustrate an example, for sub-20nm IC technologies, Ultra-Thin Body Silicon on Insulator (UTB-SOI) and FinFET were proposed in order to address the problems derived from the short-channel effects of Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) like decreased sub-threshold voltage ($V_t$) and increased device variations by eliminating the leakage paths far from the gate [13], [14]. Hence, more efforts are needed for circuit design with such new types of devices. Likewise, system designers must deal with the issues and challenges for system design in nanometer-scale technologies (inferior to 100nm). Chang [15] remarked three challenges in system design: escalating cost, design complexity and time to market. For example, one of the key challenges is to reduce the power dissipated by the clock tree up to 40% of the total power consumption because of the increased number of flip-flops in the system [16]. For that purpose, the clock gating method [17], [18] and flip-flop banking method [19] were proposed to save power consumption of the clock tree. On the other hand, the challenges for CAD technology are strictly related to the aforementioned manufacturing and design challenges. Thus, CAD vendors endeavor to provide users with an efficient tool to assist them in order to overcome their challenges as well as to improve the productivity [20], [21], [22].\n\nFoundries and Integrated Device Manufacturer (IDM) like STMicroelectronics fabricate chips for their customers. They must therefore provide customers with a design platform containing all necessary components such as libraries and Intellectual Property (IP) for chip design. However, the aforementioned issues complicate the development of components. In this thesis, such issues are considered from the perspective of the library development.\n\n1.1 Motivation\n\nIn order to rapidly and efficiently bridge increasing design productivity gap with advanced technology, a new paradigm is highly required for system designers as well as library providers.\n\nIn the system design, the top-down approach is recently more significant than the bottom-up to efficiently improve the productivity. Thus, many recent researches focused on this approach, for example, a new level of abstraction so-called Electronic System Level (ESL) above the familiar Register-Transfer Level (RTL) and design verification based on the formal specifications [23].\nFrom this aspect, we intend to improve the library development in a top-down approach from the specification because it is the most important starting point for library development. On the other hand, the specifications for library development consist of a cell-dependent part and a cell-independent one. The former represents functional and structural descriptions of the cell, whereas the latter represents all other information such as process parameters. Especially, the design platform specifications, which we need to deal with, cover only the cell-independent information such as Process-Voltage-Temperature (PVT) corners, CAD tool information, etc. Since such information has an impact on the cell design, we need to discuss it in order to efficiently provide this information for cell design.\n\nHowever, the design platform specifications are usually written in natural language or tabular form. Thus, they represent a collection of heterogeneous elements. Despite their excessive complexity, library developers must extract the desired data from them either manually or through their own scripts. On top of that, since the current specifications may lack a part of the required information for library development, they should also complete missing information. The lack of information for library development in the current specifications can be caused by two reasons. The first reason is the difference of the view points of the system designers and library developers. For example, the references for the cell characterization such as time threshold and unit information are not defined in these specifications because such information is required for library development but not for SoC design. The second one is the current specification creation method. The specification creation is a manual work. For this reason, it often results in missing information. For example, the specification developer may omit to mention the version of CAD tools. Such missing information leads to increase library development time because we must get it in order to accomplish the library development. Thus, dealing with the specifications depends highly on the expertise of the library developer and manual interventions. It becomes a significant bottleneck in library/IP development.\n\n1.2 Thesis Objectives\n\nThe main goal of this thesis is to precisely and rapidly provide library developers with all required information for library development from the specification in order to improve the productivity and quality of the library.\nFirstly, we propose a unified specification for library development. Secondly, this thesis describes how to efficiently cope with it by developing new methods and tools which provide library developers with a powerful way to smoothly accomplish their tasks for library development.\n\n1.3 Structure of this Manuscript\n\nChapter 2 introduces the system design flow as well as its corresponding design platform. Since this design flow is based on predefined libraries/IPs, we explain how to develop them. Then, an example of library development is described. With the help of these observations and experiments, we present crucial issues related to the specification itself and its current processing methods.\n\nChapter 3 reviews the state of the art with two traditional specifications in natural language and tabular form. In addition, Unified Modeling Language (UML) and eXtensible Markup Language (XML)-based specifications are presented as emerging ones in SoC design. STMicroelectronics’ design platform specifications are also described. Finally, we evaluate them with respect to their advantages and disadvantages.\n\nChapter 4 proposes the identification of all required data for library development and their classification. This survey helps to propose a suitable data model to represent our specification. To deal with it in an efficient way, we propose some methods to create a reliable specification and to efficiently extract data from it. Furthermore, how to verify both the specification and library is also explained at the end of this chapter.\n\nChapter 5 describes a specification language in XML named LDSpecX (Library Development Specification based on XML) based on the data model proposed in the previous chapter. Then, we present a specification platform that consists of two parts. The first one is a user-friendly GUI to create a complete and consistent specification in LDSpecX. The second one is an API to precisely and rapidly extract desired data from the LDSpecX-based specification database.\n\nChapter 6 presents the evaluation of our solutions. We show the creation of specification in LDSpecX and the development of a standard cell library from it on the proposed platform.\nChapter 7 gives the conclusion and proposes relevant directions for future work based on the researches presented in this thesis.\n2. Library\n\nDevelopment from the Design Platform Specifications\n\nContents\n\n2.1 Introduction ................................................................................................................. 7\n2.2 System-on-Chip Design Flow ..................................................................................... 8\n2.3 Design Platform ......................................................................................................... 11\n2.4 Library Development Flow ....................................................................................... 12\n 2.4.1 Specification Phase ............................................................................................ 14\n 2.4.2 Design Phase ...................................................................................................... 15\n 2.4.3 Derivation Phase ............................................................................................... 16\n 2.4.4 Validation Phase ................................................................................................. 17\n2.5 Existing Automatic System for Library Development .............................................. 17\n 2.5.1 Specification Creation Tools .............................................................................. 19\n 2.5.2 Circuit Design Tools ....................................................................................... 19\n 2.5.3 View Derivation Tool ...................................................................................... 20\n 2.5.4 Library Verification Tool ................................................................................... 22\n2.6 Example of the Development of a Standard-cell Library .......................................... 22\n2.7 Problems .................................................................................................................... 25\n2.8 Conclusion ................................................................................................................. 27\n\n2.1 Introduction\n\nThe system design requires more and more predefined libraries/IPs due to the increasing complexity of the system. Thus, foundries provide system designers with a design platform containing all necessary libraries/IPs in order to support their system design.\nThe library includes a collection of cells. Its main goal is to offer a wide range of information about the cells to system designer for integrating them into his system. For example, STMicroelectronics’s standard cell library for CMOS 28nm FD-SOI technology contains several hundreds of basic cells like combinational and sequential cells. This library package provides various library views to transmit the required cell information to all CAD tools for system design. This library package is produced according to the given library development flow with the help of an automatic system. This system permits to automatically execute more and more tasks instead of the manual work in order to improve the productivity.\n\nConsequently, to achieve the objectives of this thesis, a good understanding of such library development flow and automatic system is indispensable. Additionally, the analysis of the extremely complex relationship between the library development environment and the specification is also required because it may give a key idea to address the issues that arise in library development at the specification level.\n\nIn the following section, we present the design flow and design platform for SoC design. Then, we introduce how to develop libraries from the design platform specifications. In addition, an example of the development of a standard cell library is described. From these observations, we discuss the issues related to the specification.\n\n### 2.2 System-on-Chip Design Flow\n\nAs mentioned in the previous chapter, technology scaling brings not only attractive advantages but also significant issues and challenges. Thus, many attempts were made to address them from different angles. For system designers, the most crucial challenge is how to rapidly and reliably design the complex system which meets the system requirements. For this purpose, there are several major approaches: custom design, Field Programmable Gate Array (FPGA), standard-cell based design and platform/structured design [24]. Among them, the cell-based design technique is widely adopted to reduce the design cycle as well as to guarantee the functionality and performance of the complex system although the full custom design usually provides a high-performance system than the cell-based design [24], [25], [26], [27], [28], [29], [116], [117]. The richness or optimization of cells in the library may have a great influence on the improvement of the performance of system, for example, in terms of area, delay, and power [60], [61]. Hence, it helps to reduce the performance gap. For instance,\nHashimoto et al. [30] demonstrated that a rich library including various driving strength cells improved circuit performance close to transistor-level optimized circuits.\n\nThe cell library now plays a central role in SoC design. Various library categories are required, for example, standard-cell library and macro cells such as I/Os and memories. Like these cell libraries, the macro-cell devoted to a specific function, also known as IP, has recently become very important. In other words, the library offers a set of cells of the same category, whereas IP deals with only one block such as Pulse-Locked Loop (PLL). They have the same goal: to provide pre-designed cells for system design. As shown in Figure 2.1, the library cells and IPs account for a large part of the recent SoC up to almost 75% [82].\n\nFigure 2.1 Example of a SoC (source: ST)\n\nFigure 2.2 represents the cell-based design flow. This design flow splits into three principal steps: Front-End (FE) design, Back-End (BE) design and Sign-Off phases [24], [31]. For the integration of cells, the given library and IP packages provide the required views by CAD tools at all design steps to build a complete SoC.\nFirstly, the FE design for logical creation can begin with RTL design. This step describes the functionality of the system in Hardware Description Language (HDL) according to its specification. After the RTL design, the logical synthesis must be executed for translating an abstract form of desired circuit behavior (RTL model) into a design implementation in terms of logic gates by using logical views provided by the library/IP package.\n\nAfter FE design, the Back-End (BE) design for physical creation must be performed to create a physical view of the system so that the floor-planning and place-and-route activities should be accomplished using physical views of the library/IP package. The floor planning activity is the first step in physical design. The process of floor-planning allows analyzing the die size, selecting the packaging, placing I/Os, placing the macro cells, planning the distribution of power and clocks, and partitioning the hierarchy. Then, the placement process determines where each individual cell is physically located on the chip and the routing process permits to create the physical wire connections for the signal and power nets.\n\nFinally, the Sign-Off phase should be carried out to check the final physical layout by several criteria such as design rules and timing constraints. For this purpose, library views such as Verilog view and timing/power models are needed. This phase is absolutely critical to catch any remaining error before tape-out. The created and validated layout of a system can be delivered to fab for manufacturing.\n2.3 Design Platform\n\nThe design platform is a total solution to achieve the SoC design [32], [33], [34]. Since the system designer needs a complete set of libraries and IPs, CAD tools and design kits in conformity with his design flows and methodologies, the design platform consists of all such elements as described in Figure 2.3.\n\nIn order to develop a design platform, its specification must first be defined. This specification contains all information related to the target design platform. For each manufacturing technology, a suitable design platform should be developed according to its given specification. Except for commercial CAD tools, which are selected but not developed by definition, all the other components have to be created: libraries, IPs, and design kits including a collection of target manufacturing technology data files such as SPICE models, tech files, and DRC/LVS rule files [35].\n\nIn this thesis, we concentrate on the library development from the design platform specifications but this study can also cover IP development because both can be developed by the same activities even if the used methods and tools are slightly different.\n2.4 Library Development Flow\n\nThe traditional library development flow presented in the literature focus only on the design phase including FE and BE designs [36], [37], [38], [39], [40]. However, as shown in Figure 2.4, the library development flow in industry is more complex than that. In general, it is composed of four major phases. The first phase is to define a specification for the target technology. The second phase is to design all library cells. The third phase is to derive from the fundamental library views (e.g. layout and schematic) developed during the design phase to various CAD views for supporting various CAD flows. The last phase is to validate the library package by several criteria before their delivery to customers.\n\nThe library development requires the specification which can be divided into the cell-dependent part and cell-independent one. The cell-dependent part states the structural and functional description of the cell such as its pin name and logical functionality. On the contrary, the cell-independent part specifies all other information that are required for cell design but independent of cell such as process parameters and CAD tools’ information. This specification data become increasingly complex. To give an example, each library category\nneeds a set of PVT corners for its cell design. The number of required PVT corners increases with the evolution of manufacturing technology. Figure 2.5 shows the increasing number of PVT corners for standard cell library according to the manufacturing technology. In addition, the required PVT corners may be multiplied by the necessary library categories.\n\n\n\nWhere can the library developers obtain such cell-independent information?\n\nUsually, they can get this information from the design platform specification because it covers most of the cell-independent information. As depicted in Figure 2.6, its scope is larger than that of the library development specification. In other words, some information of the design platform specifications is not necessary to develop libraries. For example, a list of approvers about the information may be required for specification definition but not for library development. On the contrary, the complete list of library/IP packages can be given after finishing their development. Therefore, in this thesis, we limited the scope of the specification to cover only the required information for library development because there are difficulties to deal with the entire design platform specifications under limited conditions. Taking account of it, the following subsections present each phase of the library development flow.\n2.4.1 Specification Phase\n\nThe specification phase is significantly important for library development because it aims at collecting all required information. Yuan [41] highlighted the interaction with various functional groups such as process engineering, reliability engineering, CAD tool developers, and the marketing group for gathering the environmental considerations for library development as summarized in Figure 2.7.\n\n<table>\n<thead>\n<tr>\n<th>Considerations</th>\n<th>Related Functional Group</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. Customer requirement and competitive analysis</td>\n<td>Marketing/Design Engineering</td>\n</tr>\n<tr>\n<td>2. Process limitations and reliability considerations - latchup, metal migration, ESD, hot electrons, and associated layout constraints</td>\n<td>Process, Reliability, and Design Engineering</td>\n</tr>\n<tr>\n<td>3. Performance limitations based on above</td>\n<td>Design Engineering</td>\n</tr>\n<tr>\n<td>4. Place and Route tool capabilities</td>\n<td>CAD/Design Engineering</td>\n</tr>\n<tr>\n<td>5. Chip statistics of interconnect capacitance, routability, process variation, voltage and temperature sensitivity</td>\n<td>CAD, Process, and Design Engineering</td>\n</tr>\n<tr>\n<td>6. Packaging limitations and modeling</td>\n<td>Packaging and Design Engineering</td>\n</tr>\n<tr>\n<td>7. Modeling restrictions and workarounds</td>\n<td>CAD/Design Engineering</td>\n</tr>\n<tr>\n<td>8. Tool development for the library</td>\n<td>CAD/Design Engineering</td>\n</tr>\n</tbody>\n</table>\n\nFigure 2.6 Design platform specifications vs. library development specification (source: ST)\n\nFigure 2.7 Environmental considerations for library development [41]\nBaltus [42] remarked the essential relationship between the process parameters obtained from the fabrication process development and the cell layout generation in library development as shown in Figure 2.8\n\n![Figure 2.8 Layout development flow with manual layout [42]](image)\n\nAs stated in these studies, the specification for library development must cover a wide range of information. Moreover, the information must be collected from several information owners. Thus, the specification phase is a collaborative work. It consists of collecting the information and creating a specification with the collected information. For example, we need a list of library views and CAD tools’ information for library development. The library architect defines the contents of the library package for each library category. The design kit developer determines necessary CAD tools in order to develop a design kit for supporting them. Thus, the information relevant to library views and CAD tools can be obtained from them respectively. Then, the gathered information is defined in the specification.\n\n### 2.4.2 Design Phase\n\nThe design phase is to design all library cells. This phase permits to generate all fundamental views for FE and BE designs of the system. Specifically, in accordance with the cell specification, the cell is designed and then its physical view is created by using a layout editor. However, much effort and time should be devoted to layout design because it determines the performance of the cells. For example, Bittlestone [43] stated that cell height must be considered for layout of standard cells because increasing track height allows reducing total resistance and improving performance. Additionally, power rail also influences the performance of the standard cells. Thus, layout design has to be done by taking into consideration the physical architecture.\nAfter finishing physical design, library views such as behavioral model for FE design must be produced. This design step involves generating behavioral model and timing model. Behavioral model represents the structural description and the functionality of the cell in Hardware Description Language (HDL) such as Verilog. On the contrary, the timing model containing the timing characteristics of the cell can be generated by two steps. The first step is to characterize the cell in order to extract its timing information such as delay and constraints. The second step is to create a timing model by encapsulating the obtained timing information in Liberty format which is an open source industry standard for library modeling [44]. Since it is very important to provide an accurate timing model for verifying the functionality of the system, various characterization and timing modeling methods were proposed in order to create a more accurate timing model [45], [46], [47], [48], [49], [50]. Traditionally, the timing characterization of the standard cells is based on SPICE simulations to obtain the most accurate timing information by using manufacturer-provided SPICE models although the simulations requires a lot of time. Furthermore, for timing model, Non-Linear Delay Model (NLDM) based on Look Up Table (LUT) is widely used in industry. LUT aims at providing corresponding timing information according to input slope and output load because the timing characteristics rely on them. Thus, various input slope and output load values should be applied to the simulation in order to create a LUT. Recently, for 90nm designs and below, Synopsys’s Composite Current Source (CCS) timing model based on the current instead of the voltage threshold for NLDM was proposed because it takes into account some physical effects such as Miller effects, high interconnect impedance, and noise propagation. However, it has several major inconveniences, high runtime being one of them [51], [52]. In addition, power and noise models may also be provided for analyzing the system in terms of power and noise [53], [54], [55], [56], [57]. Moreover, such characteristic models must be made for each PVT corner. It means that they will be multiplied by the number of PVT corners.\n\n2.4.3 Derivation Phase\n\nThe derivation phase allows generating various CAD views from the fundamental views in order to completely support customers’ CAD flows because some of them require their own semantics due to the lack of standardization efforts [58]. For instance, Cadence and Synopsys tools are based on different database platform OpenAccess and MilkyWay respectively [59]. For this reason, we must create these two physical databases for supporting\nboth CAD implementation flows. Consequently, all required CAD views should be created by\nthe derivation phase to satisfy all customers’ design flows.\n\n2.4.4 Validation Phase\n\nThe quality of the libraries and IPs is directly related to not only their reuse and\nintegration but also the design efficiency of SoC [62]. So they must be verified before their\ndelivery to customers. For that purpose, Lin [63] first discussed the requirements of the high-\nquality cell library such as the correct functionality of the cell, its accurate timing\nperformance and its layout having no design rule violation. Then, he classified possible errors\ninto five types: incompleteness, inconsistency, functional errors, design rule violation and\ninaccuracy. As he remarked, errors are easily made during library development process.\nTherefore, this phase is greatly needed for generating high quality library.\n\n2.5 Existing Automatic System for Library Development\n\nThe design automation is an inevitable trend in the SoC design due to the increased\ncomplexity of systems [64], [65], [66]. Likewise, it is also indispensable for library\ndevelopment [67] because it is almost impossible to manually perform all related activities.\nTherefore, an automatic system is needed to facilitate the library development execution as\nwell as to reduce its development time. Indeed, many efforts were made to develop this kind\nof system in industry but only some of them were presented in literature [68], [69] because all\nknow-how relevant to the library development is related to the competitiveness of the\ncompany. In addition, several academic researches were introduced in literature [70], [71],\n[72], [73] even if there were some limitations to entirely deal with the issues concerning\nlibrary development due to the restricted accessibility of information. For instance, Onodera\n[70] developed an automatic generation system of process-portable library named P2Lib\nwhich represents the fundamental process as shown in Figure 2.9. This system allows library\ndesigners to generate process-portable libraries from a core library containing process-\nindependent information like functional and structural information and process-dependent\ninformation. Specifically, the timing/power analyzer generates timing and power information\nof each cell from process-independent and process-dependent information and then produces\nan intermediate library containing them. From the intermediate library, the format converter\nproduces tool-specific library views. In addition, two other tools create data sheets and\nphysical library views. Finally, the proposed automatic system produces a complete set of libraries.\n\n![Figure 2.9 Overview of P2Lib][70]\n\nThe automatic library development system often consists of several in-house tools developed in programming languages like TCL, Scheme and Perl. Figure 2.10 describes the overview of STMicroelectronics’ automatic library development system with only principal in-house tools. These tools which enable to perform the activities for generating library views or verifying them cover most of the phases in Figure 2.4 except semi-automatic steps. In the following sections, we introduce how to accomplish each phase by using these specific in-house tools.\n\n![Figure 2.10 Overview of an automatic library development system (source: ST)][7]\n\n---\n\n[7]: https://example.com\n\n[70]: https://example.com\n2.5.1 Specification Creation Tools\n\nTraditionally, the specifications for library development are based on natural language and tables. Thus, according to the characteristics of the information, the specification developer defines data in natural language or tabular form so that he can store them in a file by using office tools like Word and Excel. To illustrate an example, the person in charge of the information relevant to the cell characterization has to enter manually all process parameters such as capacitive loads in the tables. Figure 2.11 shows an example of the definition of maximum capacitance in table form by using Excel. In this manner, other process parameters for cell characterization can also be defined. However, each group of process parameters must be given in different tables or different spreadsheets.\n\n<table>\n<thead>\n<tr>\n<th>A</th>\n<th>B</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>DRIVE STRENGTH</td>\n</tr>\n<tr>\n<td>1</td>\n<td>MAX CAPACITANCE</td>\n</tr>\n<tr>\n<td>2</td>\n<td>X2LOAD</td>\n</tr>\n<tr>\n<td>3</td>\n<td>0.02235</td>\n</tr>\n<tr>\n<td>4</td>\n<td>X3LOAD</td>\n</tr>\n<tr>\n<td>5</td>\n<td>0.03278</td>\n</tr>\n<tr>\n<td>6</td>\n<td>X4LOAD</td>\n</tr>\n<tr>\n<td>7</td>\n<td>0.0447</td>\n</tr>\n<tr>\n<td>8</td>\n<td>X5LOAD</td>\n</tr>\n<tr>\n<td>9</td>\n<td>0.05512</td>\n</tr>\n<tr>\n<td>10</td>\n<td>X6LOAD</td>\n</tr>\n<tr>\n<td>11</td>\n<td>0.06705</td>\n</tr>\n<tr>\n<td>12</td>\n<td>X7LOAD</td>\n</tr>\n<tr>\n<td>13</td>\n<td>0.07748</td>\n</tr>\n<tr>\n<td>14</td>\n<td>X8LOAD</td>\n</tr>\n<tr>\n<td>15</td>\n<td>0.0894</td>\n</tr>\n<tr>\n<td>16</td>\n<td>X9LOAD</td>\n</tr>\n<tr>\n<td>17</td>\n<td>0.10132</td>\n</tr>\n<tr>\n<td>18</td>\n<td>X10LOAD</td>\n</tr>\n<tr>\n<td>19</td>\n<td>0.11175</td>\n</tr>\n<tr>\n<td>20</td>\n<td>X11LOAD</td>\n</tr>\n<tr>\n<td>21</td>\n<td>0.12218</td>\n</tr>\n<tr>\n<td>22</td>\n<td>X12LOAD</td>\n</tr>\n<tr>\n<td>23</td>\n<td>0.1341</td>\n</tr>\n<tr>\n<td>24</td>\n<td>X13LOAD</td>\n</tr>\n<tr>\n<td>25</td>\n<td>0.14602</td>\n</tr>\n<tr>\n<td>26</td>\n<td>X14LOAD</td>\n</tr>\n<tr>\n<td>27</td>\n<td>0.149</td>\n</tr>\n<tr>\n<td>28</td>\n<td>X15LOAD</td>\n</tr>\n<tr>\n<td>29</td>\n<td>0.1509</td>\n</tr>\n<tr>\n<td>30</td>\n<td>X16LOAD</td>\n</tr>\n<tr>\n<td>31</td>\n<td>0.1788</td>\n</tr>\n<tr>\n<td>32</td>\n<td>X17LOAD</td>\n</tr>\n<tr>\n<td>33</td>\n<td>0.1937</td>\n</tr>\n<tr>\n<td>34</td>\n<td>X18LOAD</td>\n</tr>\n<tr>\n<td>35</td>\n<td>0.2086</td>\n</tr>\n<tr>\n<td>36</td>\n<td>X19LOAD</td>\n</tr>\n<tr>\n<td>37</td>\n<td>0.2086</td>\n</tr>\n<tr>\n<td>38</td>\n<td>X20LOAD</td>\n</tr>\n<tr>\n<td>39</td>\n<td>0.2225</td>\n</tr>\n</tbody>\n</table>\n\nFigure 2.11 Maximum capacitance (source: ST)\n\n2.5.2 Circuit Design Tools\n\nThe library designer must design all involved cells in the library according to their functional and structural description. For circuit design, he also needs the correct information about CAD tools, design kit, and various technology-dependent parameters. All such information should be obtained from the given design platform specifications. If all fundamental information is prepared, the circuit design can be performed by using CAD tools. Firstly, in order to create BE views such as schematic, symbol, and layout, a CAD tool suite for physical creation is required. The cell design is often carried out manually with expertise in designing the high performance cell in terms of area and delay. On the contrary, FE view\ngeneration can be accomplished automatically by using in-house tools such as characterization and behavioral modeling tools depicted in Figure 2.10. As a result, logical models in HDL and timing/power models can be produced for logical synthesis and timing analysis [74], [75], [76], [77], [78], [79], [80]. The logical model can be derived from only functional and structural information by using a behavioral modeling tool because it is independent of technology. On the contrary, the timing/power modeling is highly dependent on technology so that its generation requires lots of information related to the target technology for cell characterization as shown in Figure 2.12. To make accurate timing/power models, we must extract the timing/power data from the simulations under various conditions which is made of PVT corners, input slopes and output loads. The characterization tool first create SPICE input file (.cir) including a SPICE netlist, stimuli and statements for the data extraction with the given characterization conditions. Then, the obtained characteristics of the cells can usually be encapsulated in Liberty library file (.lib).\n\n\n\n2.5.3 View Derivation Tool\n\nThe library package must contain the appropriate CAD views for customers’ CAD tools supported by the design platform. The required CAD view can be created by transforming a reference view into a desired CAD view by using the view derivation tool. For\nexample, Library Exchange Format (LEF) containing physical layout information of the cells is required for place-and-route step in system design. This physical abstract view can be derived from GDSII view depending on the type of library cells. There are two possible methods to generate this view from GDSII view as described in Figure 2.13. The first method is to use Cadence tool through several steps from GDSII view to LEF view. The second method is to directly produce LEF view from GDSII view by using the design rule of Mentor Calibre [118].\n\n\n\n[59] presents two principal programs named `oa2mw` and `mw2oa` to translate between Cadence OpenAccess (OA) [119] and Synopsys Milkyway (MW) [120] databases. Figure 2.14 briefly describes the proposed method and tool for view transformation. The `oa2mw` program permits to transform Cadence OpenAccess database into Synopsys Milkyway database via the following files: Design Exchange Format (DEF), GDSII, LEF and Verilog netlist. To give an example of generating a place and route abstract (FRAM) view (Synopsys MW) from an abstract view (Cadence OA), an in-house tool first generates an abstract view. By using `oa2mw` program, the abstract view is translated into LEF view and then, LEF view can be translated into FRAM view.\n\nAs shown previously, the view derivation tool permits to generate the desired CAD views from the reference views by applying appropriate methods for each CAD view.\n2.5.4 Library Verification Tool\n\nThe current library verification tool provides several categories of check: library view list, syntax, consistency, modelization, etc. It helps to verify the completeness and correctness of the library for its high quality. For instance, the library should be verified in accordance with a list of library views to make sure if the library contains all necessary views. For that, the library verification tool reads a specification file containing this list, and then compares the generated library views with the given list of library views. In addition, the correctness of library view is also verified. For instance, an attempt to read Verilog model by synthesis tool allows checking its correctness in terms of syntax. Consequently, if the library verification tool provides more checks, the quality of the library would be more guaranteed.\n\n2.6 Example of the Development of a Standard-cell Library\n\nIn this section, we describe how to develop this standard-cell library through the library development process by using in-house tools because developing a library can be very beneficial to effectively understand the library development process with its automatic system. A standard-cell library including sequential circuits named ‘multi-bit flip-flop bank’ has been developed from BE views with the specification for 90nm CMOS technology. This\nlibrary contains 2-, 4- and 8-bit flip-flop banks. The schematic of a 4-bit flip-flop bank is given in Figure 2.15.\n\nFigure 2.15 Schematic of a 4-bit Flip-Flop Bank\n\n- **Specification Data Preparation**\n\n As mentioned above, the library development requires a large number of data that must first be gathered from the specifications. Firstly, we need a list of library views to produce a complete library package. Secondly, a list of PVT corners and a set of process parameters must be obtained from the characterization specification. Thirdly, the correct design kit and tools’ information like tool version are needed to execute tasks for library view generation and validation. Finally, for in-house tool use, the configuration of tool should be correctly fitted by defining the specific tool configuration parameters. A large part of these parameters can be obtained from the current specifications by human inspection or scripts of the library developer. The extracted specification data have been stored in several machine-readable files for in-house tools.\n\n In this observation, we needed to accomplish the FE and CAD view generation and to perform library validation. For these steps, all necessary data have been manually collected from several scattered files containing specification data in natural language or tabular form.\n\n- **Front-End View Generation**\n\n FE view generation is divided into two major tasks: timing/power models and behavioral model generations. For creating timing/power models, all library cells were\ncharacterized under three PVT corners (for best, typical and worst process corners) with various process parameters such as input slope by using SPICE simulations. The corresponding timing and power characteristics could be obtained from the simulation results for each PVT corner. As multi-bit flip-flop bank is a sequential circuit, delay, setup, hold and min pulse width must be extracted as timing information of the cell. In addition, the worst value is used to make a timing model. In contrast, leakage power and internal energy must be extracted to provide power information of the cell [107]. The obtained timing and power information was built in LUT form according to the corresponding input slope and output load values and then these characteristic information and the structural and functional description of the cell were written in Liberty library format (.lib) [44]. Furthermore, 90nm and below, CCS timing model is required so CCS timing models were also produced. Unlike timing/power model, which aims at providing the characteristics of the cells, the behavioral model gives the description of the circuit and its function. Such information could be extracted from the cell specification and then written in Verilog by using behavioral modeling tool.\n\n- **CAD View Generation from the Fundamental Views**\n\n After generating fundamental views, supplementary CAD views must be produced for the supported CAD flows. By using the view derivation tool, Liberty library files (.lib) were first compiled by Library Compiler and then, LEF file was generated from GDSII by Method 2 presented in Figure 2.13. Additionally, OpenAccess and Milkyway databases were also generated from the fundamental physical view for supporting Cadence and Synopsys CAD flows respectively.\n\n- **Library View Validation**\n\n By using the library verification tool, the multi-bit flip-flop bank library obtained from the previous phases has been verified according to the checklist below:\n\n ✓ Completeness check (library view list)\n ✓ Syntax check (Verilog, Liberty library)\n ✓ Consistency check of library views\n\n Finally, multi-bit flip-flop bank library package was obtained through the aforementioned library development process.\n2.7 Problems\n\nIn the context of this thesis, we focused on the cell-independent specification for library development. Thanks to the aforementioned observations and experiments, we remarked several crucial issues related to the specification from various view-points. These issues can be divided into two parts depending on whether they relate to the specification contents or specification processing. Many individuals like design platform developers, library architects and library developers deal with our target specifications. They can be regrouped into two groups according to their role: specification developer and specification user. The specification developer is the person who participates in creating the specifications. On the contrary, the specification user is the person who uses data obtained from the specifications. According to these two roles, the specification processing can be divided into two activities: specification creation and data extraction from the specification. Thus, the issues regarding the specification processing are also classified by these activities.\n\nAll remarked issues are summarized as follows:\n\n❖ Specification:\n\n- **Informality**: No unified formalism is currently available to define a wide range of information in the specification. As a consequence, information is often written in different ways like natural language or table form and stored in different files according to the characteristics of information and author’s ability.\n\n- **Inconsistency**: The current specifications are created by several individuals and stored in scattered files having duplicate data so that the specification may often have consistency problems like mismatching CAD tool version and naming convention.\n\n- **Missing information**: The specification developer defines a specification from the different point of view with the library developer. Thus, it is difficult to know precisely which information is required to develop libraries. In other words, there is always a gap between the information provided by specification developers and the required information for specification users which results in missing information.\n\n- **Increasing specification data volume**: Technology scaling leads to continuously increase the process variation which considerable influences the functionality of\nthe system. For instance, PVT variability causes fluctuation in timing and power for SoC designs, hence more and more PVT corners are required as shown in Figure 2.5 [43], [81], [82], [83]. In addition to technology scaling, supported library categories and new design flows also may increase the volume of specification data like the number of the necessary library views.\n\n- **Ambiguity**: The specification information is interpreted by specification developers and specification users. In order to define obvious information in the specification, the interaction between them is significantly important. However, it is not sufficiently done and thus, some information may provoke ambiguity problems.\n\n**Specification creation:**\n\n- **Lack of a unique reference database**: To define a specification requires a set of golden references such as library naming convention, tool list and library structure. However, there is no unique repository containing all references. In addition, since the existing references represent the documents in natural language and tabular form, it is difficult to centralize them. For these reasons, their accessibility can be low. It results in increasing specification creation time.\n\n- **Absence of a specification assistant tool**: The specification developer enters all specification data manually with the help of office tools. Furthermore, they prefer to copy the old specification rather than refer to the references in order to create a new specification. As a result, such tedious way may cause specification errors.\n\n- **Absence of specification checks**: The verification of specification relies on the specification developers so that the specification errors can be detected by human inspection. It is not sufficient to ensure the high quality of the specification as well as cover increasing specification data volume.\n\n**Specification data extraction:**\n\n- **Need for efficient methods and tools for the specification data extraction**: One of the important issues in library development is to extract necessary data from the specification by human inspections and individual scripts. Thus, current specification data extraction method can significantly degrade library development time. The average time consumption for the data extraction from the current\nspecifications is obtained from library developers. It is about 4 hours because most of data should be extracted manually. For example, the cell characterization requires a lot of process parameters but their extraction is now carried out manually.\n\n2.8 Conclusion\n\nIn this chapter, we have introduced the cell-based design flow and design platform for supporting this design flow. In order to produce a design platform, all of the required libraries/IPs must be developed. Firstly, the library development flow has been presented phase by phase. Then, we explained how to perform each phase in the existing automatic system. Additionally, we also developed a standard cell library containing several multi-bit flip-flop banks throughout the development flow with the help of the existing automatic system.\n\nIn summary, the library developers need to get an amount of required data from the specification for successfully accomplishing the library development. It enables to build a complete design platform. Furthermore, efficiently dealing with the specification data is one of the most important challenges in library development. Thus, all crucial issues relevant to the specification have been remarked in the previous section. By addressing these issues, we may considerably improve the productivity of the library by quickly and precisely providing all required data to the automatic library development system. For this purpose, the following chapter first reviews various kinds of the specifications presented in the literature as well as the current specifications employed by STMicroelectronics.\n3. State-of-the-art\n\nContents\n\n3.1 Introduction ............................................................................................................... 28\n3.2 Natural Language-based Specification ...................................................................... 29\n3.3 Table-based Specification .......................................................................................... 29\n 3.3.1 System Requirements Specification in SCR ...................................................... 30\n 3.3.2 ADeVA ............................................................................................................... 32\n3.4 UML-based Specification .......................................................................................... 34\n3.5 XML-based Specification .......................................................................................... 36\n 3.5.1 IP-XACT for Digital IPs .................................................................................... 37\n 3.5.2 ASDeX for Analog IPs ....................................................................................... 39\n3.6 STMicroelectronics’ Design Platform Specifications ............................................... 41\n3.7 Discussion .................................................................................................................. 42\n3.8 Conclusion ................................................................................................................. 43\n\n3.1 Introduction\n\nThe specification represents a collection of information to carry out an activity and is considered as its starting point. For instance, the component specification provides all the information relevant to cells such as their functionality and structural description for cell design. Likewise, the specification is required for library development as described in the previous chapter. However, it is highly important to determine which information must be defined in the specification and how to deal with it. We need a unified specification instead of current ones because it may facilitate to deal with its information.\n\nThere are various kinds of specifications from the natural language-based specification to the specification based on XML in order to represent the information. In this chapter, we first discuss the traditional specifications in natural language and tabular form, and the emerging specifications based on UML and XML. Furthermore, the current specifications employed at STMicroelectronics are also introduced.\n3.2 Natural Language-based Specification\n\nThe specification has often been written in natural language until now although the development of computer engineering enables to efficiently manage information. It is so because the natural language is preferred as the initial and simple way to describe the desired information. Furthermore, the component specification and system specification are also defined by designers with the same method. Thus, in system design, some previous works focused on translating the natural language-based specification into a formal description, e.g. HDL or ESL by using a semantic analysis that allows extracting the information from the given textual specifications. For example, [84] presents a translator named Semantic Parser, which is based on a syntactic parser, the Natural Language ToolKit and a semantic grammar. This parser enables to translate the natural language description of a component into a simulatable Verilog model by extracting the key information from the given sentences and rewriting it in Verilog. Similarly, [85] introduces the translation of informal textbook specifications into a formal ESL implementation such as SystemC. For this purpose, Formal Specification Level (FSL) has been proposed to bridge them. Specifically, this intermediate level allows decomposing the sentences in terms of noun, verb, and adjective by syntactic and grammatical analysis and then extracting the structure behavior and properties of the system from the decomposed sentences. Finally, the obtained information is used to create a SystemC model.\n\nDespite these previous attempts of formalization, a more precise syntactic and grammatical analysis is still highly required to obtain the desired information from the complex textual specifications. If it is not available, the specification authors must use simple sentences and restricted words as well as pay an attention to create a simple specification. Nevertheless, since the natural language-based method offers authors a great freedom in defining a specification, there are always possibilities to cause errors such as inconsistency and misunderstanding. Furthermore, as is well known, dealing with this specification is a tedious and time-consuming job.\n\n3.3 Table-based Specification\n\nThe table-based method is as popular as the natural language-based method to represent the specification thanks to the facility of entering data in a table and capturing\ndesired data from that. However, by using tables, we must refine the information in comparison of natural language. It means that only the necessary data should be stored in tabular form after removing the redundant one. Hence, the table-based specification gradually replaces a large part of the natural language-based specification to describe the specification of a component or system as a more efficient method. The following subsections introduce two table-based specifications.\n\n### 3.3.1 System Requirements Specification in SCR\n\nIn the late 1970s, Software Cost Reduction (SCR) method, which is based on “user-friendly” tabular notation, was applied to design software systems developed by David Parnas and researchers of the U.S. Naval Research Laboratory (NRL) [86]. The requirements specification in SCR tabular notation refers to a repository for all information required by developers to construct the software for a computer system. During the 1980s and 1990s, it has been used in many industrial organizations including Lockheed, Grumman, Bell laboratory and so on thanks to its scalability and cost-effectiveness. On top of that, a complete tool set for 1) creating, 2) debugging, 3) validating and 4) verifying this specification has been developed over a decade or more. By using this tool set, constructing the requirements specification for an automatic Cruise Control System (CCS) is introduced in [87], [88]. Figure 3.1 specifies this automatic system in SCR.\n\n![Figure 3.1 The cruise control system in SCR [88]](image)\n\nCreating the requirements specification in SCR notations for the system in Figure 3.1 requires two kinds of tables: function and dictionary. Function table gives the change of the value of the mode by the event of variables. For example, Figure 3.2 gives a function table to describe the mode transition of `mcCruise` depicted in Figure 3.1. This table represents a finite\nstate machine to give the new mode (destination mode) of the system as a function of current mode (source mode) and the monitored variables (events).\n\nFigure 3.2 Mode transition table defining the mode class mcCruise [88]\n\nOn the contrary, dictionary table contains the fixed information such as variable declarations, environmental assumptions, and type definitions. To give an example of the dictionary table, Figure 3.3 shows a variable dictionary that defines the types, initial values and accuracy requirements of all variables. The monitored variables like mIgnOn for the CCS are also given in this table. These variables are used for the event in the above mode transition table.\n\nFigure 3.3 Variable dictionary table for the CCS [88]\nBy using a specification editor, all necessary tables can be created. After the creation of this specification, several checkers permit to check its well-formedness by detecting various errors such as consistency, property, and dependency. Additionally, the checked specification is also validated to ensure that it meets the customers’ needs and analyzed to verify the properties of the application.\n\n### 3.3.2 ADeVA\n\nInstead of using large natural language documents to represent the specification of the system, Advanced Design and Verification of Abstract Systems (ADeVA) has been developed on the basis of the concept of SCR notation explained above. It also provides two types of tables: Mode Transition Table (MTT) and Data Transformation Table (DTT) which are function and dictionary tables respectively [89]. Some specification tools based on ADeVA have been introduced in the literature. Alcatel-Lucent Technologies developed a specification editor named SpecEdit using ADeVA for the specification of a complex telecommunication system [90]. Figure 3.4 shows its Graphic User Interface (GUI) which enables users to enter data in MTT and DTT to describe the behavior of the system.\n\n![Figure 3.4 SpecEdit GUI [89]](image-url)\nFigure 3.5 shows a MTT that gives the symbol to indicate an event (T/F, @T, -, etc.) under the given condition when a state transition occurs. Figure 3.6 illustrates a DTT defining the event symbol under different conditions according to the given value of the signal. Similarly, [91] also presents a specification platform based on ADeVA notations for representing the requirements specification of the embedded system.\n\n<table>\n<thead>\n<tr>\n<th>From</th>\n<th>To</th>\n<th>UNI C cmd = CC_Req</th>\n<th>UNI C quality</th>\n<th>UNI N cmd = CC_Resp</th>\n<th>UNI N quality</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Wait_Req</td>\n<td>Check_Req</td>\n<td>@T</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n</tr>\n<tr>\n<td>Check_Req</td>\n<td>Wait_Req</td>\n<td>-</td>\n<td>T</td>\n<td>-</td>\n<td>-</td>\n</tr>\n<tr>\n<td>Check_Req</td>\n<td>Wait_Resp</td>\n<td>-</td>\n<td>F</td>\n<td>-</td>\n<td>-</td>\n</tr>\n<tr>\n<td>Wait_Resp</td>\n<td>Wait_ONONS</td>\n<td>-</td>\n<td>-</td>\n<td>@T</td>\n<td>T</td>\n</tr>\n</tbody>\n</table>\n\nFigure 3.5 Example of MTT [89]\n\n<table>\n<thead>\n<tr>\n<th>Output</th>\n<th>Value</th>\n<th>UNI Network State = wait for Resp</th>\n<th>UNI Network State = wait for ONNS</th>\n<th>UNI Network CC_Table AND ins = 2</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>UNI N.cmd</td>\n<td>CC_Req</td>\n<td>@T</td>\n<td>F</td>\n<td>-</td>\n</tr>\n<tr>\n<td>UNI N.cmd</td>\n<td>CC_Resp</td>\n<td>-</td>\n<td>@T</td>\n<td>T</td>\n</tr>\n</tbody>\n</table>\n\nFigure 3.6 Example of DTT [89]\n\nIn summary, the table-based specification provides some important advantages. One of the interesting advantages is to easily extend the specification by simply adding supplementary columns or rows. Another is to rapidly get the desired data from the corresponding table by matching each column with the given condition in comparison with the natural language-based specification that mainly relies on the human inspection or syntactic analysis. In addition, the specification creation and data extraction can be accelerated by using the predefined form. However, this kind of specification also has several important limitations. First, since a table represents a set of data of the same type, the specification containing a variety of data should be defined by using many tables. For instance, to cover the system requirements specification of CCS described previously, three function tables and six dictionary tables are needed. Second, it is difficult to understand the relationship between tables. For this reason, an additional specific tool must be developed to visualize the dependency of data in different tables as shown in Figure 3.7 [88]. It means that we need an additional work to identify the relationship of the tables.\n3.4 UML-based Specification\n\nUML is a modeling language using graphical notations for creating visual models of the system in software domain [92]. This language provides a set of diagrams (e.g. class diagram, sequence diagram, use case diagram, activity diagram, etc.). These diagrams can be classified into two groups depending on the characteristic of the model: structure and behavior diagrams as depicted in Figure 3.8 [112].\n\nFigure 3.8 Taxonomy of structure and behavior diagrams [112]\nUML allows rich expressive capabilities by using diagrams so that it can be quickly applied to various other domains including SoC. For instance, the authors of [93] proposed a SoC validation method based on UML and Component Wrapper Languages (CWL) for modeling the component specification and the interface protocol specification respectively. Figure 3.9 describes the specification based verification process which consists of two steps: specification validation and SoC verification. First, the specification in natural language is validated by checking its completeness and consistency with the help of UML models and CWL. Second, the functionality of the target system can be verified by using test scenarios derived from the UML models of the system.\n\nFigure 3.9 Specification based verification process [93]\n\n[94] presents how to create SoC specification by using UML models and actor-oriented modeling. The authors emphasized the efficiency of modeling the static and dynamic nature of a system in SoC design by using a number of UML diagrams. For example, UML class diagram provides a static view of the system by describing blocks of the system using the class and the relationship among them by the connection lines as shown in Figure 3.10.\n\nFigure 3.10 UML class diagram [94]\nOn the contrary, UML sequence diagram represents the interaction among classes over the time. Figure 3.11 shows the sequence of the communication between a sender and a receiver to describe the behavior view of the system.\n\n\n\nFigure 3.11 UML sequence diagram [94]\n\nTo summarize, the UML-based specification enables to describe the structural and behavioral system specification more comprehensively by means of graphical notations than the aforementioned traditional specifications. However, UML diagrams are considered as conceptual models. Thus, extracting the desired information from the UML-based specification requires the interpretation of the related diagram.\n\n### 3.5 XML-based Specification\n\nThe XML is a subset of Standard Generalized Markup Language (SGML) [95]. It becomes a W3C recommendation language to store many different kinds of data in textual form with markup tags on Web [96]. The main contribution of this language is to represent metadata in order to exchange information across different systems. Additionally, it provides several important benefits such as extensibility, flexibility, availability of various data types, portability, and machine-readability. Thanks to its advantages, XML is widely applied to various areas. Recently, it is used as an emerging method in SoC design to represent the specification. For example, IP-XACT has been proposed by SPIRIT consortium [98] as an XML-based specification language to describe the specification of digital IPs. Similarly, Analog Specification Description in XML (ASDeX) for analog IPs has been introduced in the literature [106]. The following subsections present these XML-based specification languages in detail.\n3.5.1 IP-XACT for Digital IPs\n\nIP-XACT standard has been developed for packaging, integrating, and reusing IPs provided by different vendors within tool flows [98]. This standard provides an efficient way to describe and interpret metadata for IP integration and configuration requirements with the help of its well-formed XML schema that describes the syntax and semantic rules [97]. Furthermore, the IP-XACT schema provides seven top-level schema definitions: bus definition, abstraction definition, component, design, abstractor, generator chain, and design configuration. Each schema definition can be used to encapsulate the object description. For example, the bus definition object defines the information of a bus. Its schema contains a set of elements and attributes to encapsulate the appropriate information. Figure 3.12 illustrates all objects and their interactions. As described in this figure, the interaction between objects is denoted by the arrow. This arrow (A → B) represents a reference relationship of one object to another (e.g. reference of object B from object A).\n\n![Figure 3.12 IP-XACT data object interactions [98]](image-url)\nFigure 3.13 IP-XACT design environment [98]\n\nFigure 3.13 describes the IP-XACT design environment. This design environment enables the system designer to create and manage the top-level meta-description of a system by using IP-XACT design IP. For this purpose, it provides two types of services: design capture and design build. The design capture is to capture the structure and configuration information of imported IP by a system design tool. The design build is to achieve the integration and configuration of required IP by using generators provided by a system design tool. Indeed, IP-XACT specifications are being broadly adopted by IP and EDA vendors through their own IP-XACT enabled design environment [99], [100], [101], [102], [103]. To give an example, an environment named Kactus2 for embedded product development is presented in [101]. This system uses IP-XACT to describe HW components. To search component, the authors introduced the component capture method based on a tuple \\{Vendor, Library, Name, Version\\} (VLNV) that is given as a unique identifier by the IP-XACT object description. Furthermore, to improve this VLNV-based method, [102] and [103] introduce the extended IP selection method and an unambiguous VLNV naming convention respectively. The former paper highlights that nonfunctional information such as power dissipation should also be considered to find and select functionally suitable ones among many different predesigned components in IP libraries. The authors thus proposed to describe components by...\nusing an extended IP-XACT with important additional information and to filter them by criteria based on keywords and nonfunctional information. As a result, the proposed method aids to select the best-suited components. The latter paper introduces unambiguous VLNV naming conventions by using keywords which are based on detailed taxonomy of components. Hence, the VLNV name composed of keywords helps to find the appropriate ones by removing its ambiguity.\n\n3.5.2 ASDeX for Analog IPs\n\nIP-XACT is a specification language for digital IPs but unfortunately it is not suitable for analog IPs. For this reason, ASDeX has been proposed as a specification language in XML to describe the specification of analog circuits in [104], [105], [106]. This language covers all the required information for the automatic design validation with it. Figure 3.14 shows the schema of ASDeX which consists of the identifier block design, the main block specification and the three optional blocks function, testbench and task. These blocks and their interactions are described in Figure 3.15. As stated in the previous subsection, the arrow represents the reference relationship between blocks. For instance, the specification description is referenced by tasks and testbenches.\n\nFigure 3.14 Schema of ASDeX [104]\nIn addition, a validation work flow is introduced to validate analog circuits by using ASDeX as described in Figure 3.16. This work flow is based on the Essence Framework and the meta-simulator. Especially, the Essence Framework transforms ASDeX specification into an execute task for validating circuits. To achieve this validation, all the required information for building up a testbench, simulation setup and result calculation could be extracted from ASDeX documents by using the templates derived from the template library. The same authors also presented an Application Programming Interface (API) named AXEI (ASDeX Engine Interface) to derive the desired information from the specification more easily than using the templates in [106].\n\nAs shown above, the XML-based specification represents a tree data structure that allows encapsulating various data sets. As a consequence, it enables to store all necessary data in an XML format file in accordance with the pre-designed XML schema. The previous\nstudies show well the facility of capturing data from the XML documents by using templates thanks to its machine-readability. Furthermore, several software supports for XML and XML-specific language like eXtensible Stylesheet Language Transformations (XSLT) [110] greatly help to deal with XML documents. However, both IP-XACT and ASDeX propose an appropriate data model for the component description.\n\n### 3.6 STMicroelectronics’ Design Platform Specifications\n\nAs mentioned in the previous chapter, the current design platform specifications at STMicroelectronics are a collection of heterogeneous information from technology-dependent parameters to CAD tools’ information. Thus, these specifications are made by natural language-based and table-based documents as given in Figure 3.17. From the perspective of end-users like library developer, these types of the specifications become more and more difficult to extract the desired data from them due to their increasing complexity with technology scaling and different forms. In addition, the data extraction depends on human inspection or scripts of the library developer. Thus, we need a unified form to cover all of the specifications as well as novel methods to cope with it.\n\n\n\n\n\n*Figure 3.17 STMicroelectroines’ design platform specifications (source: ST)*\n3.7 Discussion\n\nWe have previously seen four kinds of the specification. Table 3.1 summarizes their advantages and disadvantages. As given in this table, there are six and four criteria for data modeling and data processing respectively. According to these criteria, each specification has been estimated. In the table, the circle symbol represents “good” and the X symbol represents “bad”. To give an example, for data modeling, the natural language-based specification provides good extensibility, flexibility, expressiveness and availability of various data types for data modeling, whereas it has bad formality and data relationship. In addition, for data processing, it gives good facility of entering data and human readability but bad facility of capturing data and machine-readability. Likewise, the advantages and disadvantages of other specifications are also given. On the contrary, STMicroelectronics’ design platform specifications have both the features of the natural language-based and table-based specifications.\n\nTable 3.1: Summary of the specifications\n\n<table>\n<thead>\n<tr>\n<th>Criteria</th>\n<th>Natural language-based specification</th>\n<th>Table-based specification</th>\n<th>UML-based specification</th>\n<th>XML-based specification</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Data Modeling</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Formality</td>\n<td>X</td>\n<td>O</td>\n<td>O</td>\n<td>O</td>\n</tr>\n<tr>\n<td>Extensibility</td>\n<td>O</td>\n<td>O</td>\n<td>O</td>\n<td>O</td>\n</tr>\n<tr>\n<td>Flexibility</td>\n<td>O</td>\n<td>O</td>\n<td>O</td>\n<td>O</td>\n</tr>\n<tr>\n<td>Expressiveness</td>\n<td>O</td>\n<td>O</td>\n<td>O</td>\n<td>O</td>\n</tr>\n<tr>\n<td>Availability of various data types</td>\n<td>O</td>\n<td>O</td>\n<td>O</td>\n<td>O</td>\n</tr>\n<tr>\n<td>Data relationship</td>\n<td>X</td>\n<td>X</td>\n<td>O</td>\n<td>O</td>\n</tr>\n<tr>\n<td>Data Processing</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Facility of entering data</td>\n<td>O</td>\n<td>O</td>\n<td>X</td>\n<td>O</td>\n</tr>\n<tr>\n<td>Facility of capturing data</td>\n<td>X</td>\n<td>O</td>\n<td>X</td>\n<td>O</td>\n</tr>\n<tr>\n<td>Human readability</td>\n<td>O</td>\n<td>O</td>\n<td>X</td>\n<td>O</td>\n</tr>\n<tr>\n<td>Machine readability</td>\n<td>X</td>\n<td>X</td>\n<td>X</td>\n<td>O</td>\n</tr>\n</tbody>\n</table>\n3.8 Conclusion\n\nIn this chapter, we presented natural language-based and table-based specifications. In addition, the UML-based and XML-based specifications were introduced. The current specification used at STMicroelectronics was also discussed. The advantages and disadvantages of these specifications were compared and then the comparison results were given.\n\nConsequently, we first need a unified specification to represent all required information independent of cells for library development instead of the current ones. The above table shows that the best form of the specification is the XML-based specification over all criteria. Thus, we aim at proposing an XML-based specification thanks to its attractive benefits and software supports. However, we must propose a suitable one because of the absence of the XML-based specification for our target information. On top of that, we also need efficient methods to create a reliable specification and to extract desired data from the target specification.\n\nIn the subsequent chapter, we try to provide answers to the following question:\n\n- How can we propose an XML-based specification for the specifications of library development?\n- How can we create a reliable specification?\n- How can we precisely and rapidly extract the required information from the specification?\n4. **Methodology for Library Development Specifications**\n\n**Contents**\n\n4.1 Introduction ............................................................................................................... 44\n4.2 Formalism of the Specification .................................................................................. 45\n 4.2.1 Requirements of the Specification ................................................................. 45\n 4.2.2 Specification Data Analysis ............................................................................ 46\n 4.2.3 Specification Data Classification ..................................................................... 50\n 4.2.4 Specification Data Modeling .......................................................................... 54\n a) Data object ........................................................................................................ 54\n b) Relationship of data objects ............................................................................ 57\n4.3 Reliable Specification Creation Method .................................................................. 60\n 4.3.1 Reference Database ......................................................................................... 60\n a) Dictionary .......................................................................................................... 60\n b) List reference ..................................................................................................... 61\n 4.3.2 Specification Creation using a Reference Database ........................................... 63\n4.4 Efficient Method for Data Extraction from the Specification ................................. 63\n 4.4.1 Keyword for Precise Data Identification ......................................................... 64\n 4.4.2 Task-based Keywords for Efficient Data Extraction ........................................ 65\n4.5 Validation of the Specification ................................................................................ 66\n4.6 Validation of the Library against the Specification .................................................. 68\n4.7 Conclusion ............................................................................................................... 69\n\n**4.1 Introduction**\n\nOne of the most crucial issues for dealing with our target specifications is to create a unified specification, which could contain a wide variety of information independent of cells.\nIn addition, for efficient data processing, we also have two important challenges. The first is how to create a reliable specification containing a huge amount of various data. The second is how to precisely and rapidly extract the desired data from it in order to accomplish the library development process.\n\nIn this chapter, we first introduce an appropriate data model to represent the specification for library development. Furthermore, two key methods are presented for specification creation and specification data extraction. Additionally, some approaches to verify the specification and library are also discussed.\n\n4.2 Formalism of the Specification\n\nBefore discussing the formalism of specification, we have to clarify its requirements. Then, the identification and classification of specification data are required, i.e. we need to collect all required information for library development and analyze it. These studies may help to propose a suitable data model for our target information.\n\n4.2.1 Requirements of the Specification\n\nThe objective of the specification is to provide the library developers with all required information for successfully accomplishing their work. From this perspective, the most important requirements of the specification were given as follows:\n\n- **Formality**: The specification covers various categories of information. The data in each category must be formalized by determining their essential elements to give complete information. This formality enables to define all necessary specification data in a unified way.\n\n- **Consistency**: The information given in the specification should be consistent to avoid mismatch errors which can greatly impact the quality of the library.\n\n- **Completeness**: Since the current specifications do not provide complete information for library development, library developers have difficulties in finding missing information. Thus, if all required information is defined in the specification, they are able to get all necessary information from a unique source quickly.\n- **Extensibility**: The technology evolution leads to increase the volume of specification data. For this reason, the specification data model has to address increasing data volume.\n\n- **Unambiguosness**: The information in the specification must be comprehensible and unambiguous for all library developers. It aids to reduce specification errors like misunderstanding.\n\n### 4.2.2 Specification Data Analysis\n\n\n\nAt STMicroelectronics, the library development is carried out by using an automatic library development system based on in-house and commercial CAD tools as described in Figure 2.10. This automatic system covers aforementioned three main phases for library development: FE view generation, CAD view derivation and validation phases. Figure 4.1 describes the hierarchical layers of the system and the interoperability between integrated tools at different layers. At the top layer, a flow management tool controls the whole process by using the specific in-house tools. These in-house tools at the intermediate layer execute all tasks for generating, deriving, and validating the library views with the help of CAD tools and a design kit.\n**Task for library development**\n\nA task permits to generate more than one view or to verify it using the given input data and the corresponding tool.\n\nFigure 4.2 describes how the in-house tool executes a task for library development. This tool requires a set of input data to produce output data. As shown in this figure, the input data splits into three groups. The first group includes the view obtained from the previous task. The second group represents the information concerning the cells such as their functional and structural description. The third group represents all other information. A large part of the other information can be extracted from the current design platform specifications, whereas the remaining information may be gathered from several sources such as library developer’s knowledge and individual documents.\n\nThe necessary input data for each task can be determined by the characteristics of the target task. For example, the task to produce a behavioral view requires only cell information because the behavioral view such as Verilog model mainly includes the structural and functional description of cells which can be used for the RTL design of the system. On the contrary, generating a timing model of the cell is highly dependent on technology and thus this task needs not only a SPICE netlist file and cell information but also a number of technology parameters as input data.\nIn this thesis, we focus on input data of the third group, i.e. data that are not related to the cell but to the design platform, library developer’s knowledge and individual documents. Firstly, all input data for cell characterization, behavioral modeling, and CAD view generation were identified and classified according to the data categories. For example, the characterization tool for timing model generation performs the cell timing characterization with various data. The required input data for the timing characterization of a non-scan D flip-flop named DFPQX2 are given in Figure 4.3. First, Spice simulator performs the simulation. Second, design kit provides Spice models. Third, Spice netlist of this flip-flop can be obtained from the Spice file (.spi). Finally, the information about technology parameters such as PVT corner, slopes of pin D and of pin Clock for the given PVT corner, and capacitive loads for drive strength (X2) are needed. By using all these parameters, the characterization tool generates a circuit file (.cir) including the condition of the simulation, the spice netlist, the statements of data extraction and so on. The simulation can be accomplished with this circuit file and the desired timing information can be measured. As a consequence of the timing model generation, a Liberty file (.lib) containing the timing information of the cell can be produced.\n\nFigure 4.3 Timing characterization of a non-scan D flip-flop (source: ST)\nBy the same method, the input data for other tools could be analyzed. All required data for each tool are divided into three data groups: tool, technology and view. According to this, the identified parameters could be classified and counted. Figure 4.4 gives the tool input data analysis results. The results show that the dominant parameters rely upon the characteristics of the activity of the tool. For instance, as depicted in this figure, the characterization tool needs a set of technology-dependent parameters as well as a large amount of tool configuration parameters that are employed in running the accurate simulation.\n\n\n\nIf all of these parameters collected from different sources are defined in a specification, the library developer can easily get complete information from a unique source. But a supplementary data group needs to be added to provide the information about the design flows supported by the library. This is because the supported design flows determine which library view must be produced and which tools are needed for system design and library development. It can provide the bridge between tool and view information. Thus, we propose four main data groups: technology, tools, views and design flows.\n4.2.3 Specification Data Classification\n\nClassifying the specification data in detail is significantly important for data modeling. In the previous subsection, we present four main data group. Further, we also propose subgroups for each data group to present the detailed taxonomy of data as shown in Figure 4.5.\n\n\n\nNow, we present which data can be included in each data group as follows:\n\n- **Technology**\n \n The technology data group must cover all technology-dependent parameters from fundamental technology information to process parameters for characterization. The concerned information was regrouped into four data subgroups by the characteristics of data as described in Figure 4.5.\n\n - **General Technology Parameters**: represents the fundamental technology information independent of library category. For example, the target technology node can be regarded as a general technology parameter.\n\n - **Specific Technology Parameters**: represents the fundamental technology information dependent of library category. For instance, the library architecture may be regarded\nas a specific technology parameter because there are several different library architectures by the number of tracks for standard cell library and by the type of frame for I/O library. The values of this parameter rely on the target technology.\n\n- **PVT corners**: represents PVT corner lists. The PVT corner list should be given for each library category because the required PVT corners or the essential elements of a PVT corner can be different. For instance, for the operating condition, one supply voltage is needed for standard cells, whereas memories may need two supply voltages.\n\n- **Characterization Parameters**: provides all necessary process parameters for cell characterization. Specifically, characterization references, slopes, and capacitive loads can be included in this data subgroup.\n\n- **Tools**\n\n The main goal of this data group is to provide the user with a complete list of all necessary tools and design kit. Additionally, this data group can contain tool configuration parameters.\n\n - **Tool**: provides the underlying information about a tool such as tool name and tool version.\n\n - **Tool Configuration Parameters**: provide the specific configuration parameters according to the purpose of the tool. These parameters are missing in the current specifications in spite of their importance and needs. Moreover, the tool configuration is one of the most time-consuming steps in library development. Thus, this data subgroup aims at automatically setting up the correct tool configuration.\n\n- **Views**\n\n The main goal of this data group is to give a list of library views to produce a complete library package. In addition, this data group may also include view attributes.\n\n - **View**: provides the underlying information about a view such as its view path that specifies its physical location in the directory structure of the library. In addition, it determines whether the view should be generated by the library category. For example, IP-XACT library view is required for memories and IPs but not for standard cell library.\n\n - **View Attributes**: provide the specific attributes of a library view. Generally, the definition of view attributes totally depends on the tool that generates the view. Unfortunately, it does not ensure whether they are well defined in the view. For this\nreason, to provide these specific view attributes is proposed to correctly generate a view with them. For example, Liberty library has its own specific attributes, for example, *direction* attribute for specifying the direction of a pin [44]. The view attributes must be defined at different levels such as library, cell and pin depending on which level relates to the information given by it.\n\n- **Design Flows**\n - **SoC Design Flow**: provides the information about the supported design flows by the library.\n\nFinally, most of the identified data were classified according to the data taxonomy mentioned above. Table 4.1 gives the classified specification data. For example, the general technology parameters data subgroup contains all technology parameters independent of library category: technology name, technology node, process, metal option, voltage option, Resistor and Capacitor (RC) type, maximum temperature, minimum temperature, and Design Rule Manual (DRM). Likewise, other parameters are also classified in the corresponding data group. If there are new parameters, the specification developer can easily add them to one of the related data group.\nTable 4.1: Specification data\n\n<table>\n<thead>\n<tr>\n<th>Technology</th>\n<th>PVTs</th>\n<th>Characterization Parameters</th>\n<th>Tool Configuration Parameters</th>\n<th>Views</th>\n<th>View Attributes</th>\n<th>SoC Design Flow</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>General Technology Parameters</td>\n<td></td>\n<td></td>\n<td>Technology name, Technology node, Process, Voltage option, Metal option, Resistor and Capacitance type, Max. temperature, Min. temperature, Design rule manual</td>\n<td></td>\n<td></td>\n<td>Commercial CAD tools (Layout editor, synthesis tool, SPICE simulator, etc.) In-house tools (Characterization tool, Behavioral modeling tool, CAD derivation tool, validation tool) Design kit</td>\n</tr>\n<tr>\n<td>Specific Technology Parameters</td>\n<td></td>\n<td>Characterization tool configuration parameters, Behavioral modeling tool configuration parameters, View derivation tool configuration parameters</td>\n<td>Documents, IP-XACT, Verilog, VHDL, Symbol library, Liberty library, CCS library, ECSM library, LEF, DEF, CDL, OpenAccess, Milkyway, ATPG</td>\n<td>Liberty library attributes</td>\n<td>FrontEnd, BackEnd, SignOff</td>\n<td></td>\n</tr>\n<tr>\n<td>PVTs</td>\n<td></td>\n<td>Slope</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Process, Voltage, GND, Temperature, Age</td>\n<td>Time, threshold, Slope threshold, Cap threshold Time unit, Load unit, Load unit, Power unit, Voltage unit, Energy unit, Glitch tolerance, Peak tolerance</td>\n<td>Max transition(Clk), Max transition (Data), Max transition (TestIn), Last index (Clk), Last index (Data), Last index (TestIn), Intermediate values constraint (Clk), Intermediate values (Data), Intermediate values (TestIn)</td>\n<td>Max capacitive load (worst corner), Max capacitive load (best, typical corners), Index timing, Index power</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n4.2.4 Specification Data Modeling\n\nData model describes the data objects with their properties and the relationship between objects in order to represent the real world. From this aspect, we created an appropriate data model to describe the specification for library development on the basis of the observations about the specification data presented previously.\n\nThe specification data model consists of seven main data objects encapsulating the categorized data given in Table 4.1. Figure 4.6 represents all data objects as well as the reference relationship between them.\n\n\n\na) Data object\n\n**Data object**\n\nA data object (indicated by a gray box) represents one or more parameter sets.\n\nOne of the most important issues is to represent a variety of data objects in a unified way. For this reason, we need a generic and simple data model that enables to represent the parameter set. We propose a basic data model for the data object as shown in Figure 4.7 by\nusing UML class diagram notation [112]. The parameter set may represent more than one parameter. The parameter information can be given with its name and value elements. This data model is used to create the specification data model over all data objects.\n\n\n\n**Figure 4.7 Basic data model of the data object**\n\nThere are two types of data objects depending on whether their parameters are subcategorized or not. Figure 4.8 illustrates the example of these different types. As shown in Figure 4.8 (a), since *General Technology Parameters* data object contains a set of general technology parameters regardless of the library category, it may be referred as the first type. In contrast, *Specific Technology Parameters* data object may be referred as the second type because it may contain several subsets (so-called List) of technology parameters subcategorized by the library category as described in Figure 4.8 (b).\n\n\n\n**Figure 4.8 Examples of (a) non-subcategorized parameter set (b) sub-categorized parameter set**\n\nAs described in Figure 4.7, in order to define the parameter information, we propose a simple unified way to give its name and values. In addition to these fundamental elements, the key attribute is used as an identifier at STMicroelectronics to identify the tool and view instead of its name. However, there is no common agreement for naming the key attribute. For this reason, we propose a naming convention for the key attribute as follows:\n\n\\[\n\\text{key} = \\text{<identifier>_<purpose>}\n\\]\nThe key is composed of two fields: identifier and purpose. The first field identifier is a mandatory field to give identification information. The second field purpose is an optional field to give the specific purpose of the tool or view that may relate to the activity of the system design or library development. In addition, this attribute can also be used to link its parameter with other parameters. For instance, a tool and its suitable configuration parameters are coupled by the tool key. As given in Table 4.1, both the characterization tool and its configuration parameters may be identified by their same tool key. Likewise, a view and its view attributes can be coupled via the view key.\n\nConsequently, there are two kinds of parameter data model according to the presence or absence of the key attribute.\n\nFigure 4.9 Examples of (a) parameter without key attribute (b) parameter with key attribute\n\nFigure 4.9 (a) represents the first kind of parameter. As shown in this figure, the general technology parameter can be defined by a parameter name and values. For instance, a technology node can be expressed as follows:\n\n\\[\n\\text{General Technology Parameter Name} = \\text{\"TechnoNode\"}\n\\]\n\n\\[\n\\text{General Technology Parameter Value} = \\text{\"28\"}\n\\]\n\nAdditionally, when the parameter has more than one value, we can assign a value identifier attribute named id to each value. For instance, the information about process can be given as below:\n\n\\[\n\\text{General Technology Parameter Name} = \\text{\"Process\"}\n\\]\n\n\\[\n\\text{General Technology Parameter Value} = \\text{\"ff\", id = \"best\"}\n\\]\n\n\\[\n\\text{General Technology Parameter Value} = \\text{\"tt\", id = \"typical\"}\n\\]\n\n\\[\n\\text{General Technology Parameter Value} = \\text{\"ss\", id = \"worst\"}\n\\]\nFigure 4.9 (b) represents the second kind of parameter. As described in this figure, the tool information consists of a tool name, version and key attribute. As explained previously, the tool key attribute is used to identify the desired tool. Especially, in the case that CAD vendor offers a tool suite containing several tools, this attribute is very useful to identify the desired tool instead of the name of tool suite. For instance, since Synopsys provides a tool suite named \\texttt{synthesis} providing Design Compiler, Library Compiler, etc., we have to load \\texttt{synthesis} to use Design Compiler. Thus, the tool information for Design Compiler can be given as follows:\n\n- **Tool Key** = \"designcompiler\\_synthesis\"\n- **Tool Name** = \"synthesis\"\n- **Tool Version** = \"i-2013.12\"\n\n\\textbf{b) Relationship of data objects}\n\nWe defined the data objects of the specification above. Now, we note the relationships between them expressed by the arrow as shown in Figure 4.6. Even if the data objects are structurally independent of each other, there are relationships between their information, which can be identified by the common element of data objects.\n\nFirstly, ‘Characterization Parameters’ data object depends on ‘PVTs’ ones because the process parameters for cell characterization, like slopes, change by the PVT corner. For this reason, the number of required slope values depends on the number of the given PVT corners. The relationship of these data objects can be identified by PVT corner’s name.\n\nSecondly, in order to perform design activities, we need CAD tools and library views at each step. It means that the design flow has an important influence on determining which tools and library views should be required so that ‘Tools’ and ‘Views’ data objects are related to ‘Design Flows’ data object. We propose to use the key attribute in order to define the relationship between these three data objects. As mentioned above, the key attribute contains a purpose field. In order to link the design flow with tools and views, the purpose field of the key attribute should be based on the supported design flow. For example, the information about Front-End design flow can be defined in ‘Design Flows’ data object as follows:\n\n- **SoC Design Flow Name** = “FrontEnd”\n- **SoC Design Flow Value** = “synthesis”\nAs is well known, we need a synthesis tool like Design Compiler and a Verilog model for the logical synthesis and thus the key attributes relevant to these elements can be expressed as follows:\n\n\\[\n\\text{ToolKey} = \\textit{designcompiler_synthesis}\n\\]\n\n\\[\n\\text{ViewKey} = \\textit{verilog_synthesis}\n\\]\n\nConsequently, Figure 4.10 represents a complete data model of the specification which is made up of basic data objects described in Figure 4.6. This data model covers the data given in Table 4.1. As shown in this figure, the class name is simplified instead of a being long name. For example, ‘General Technology Parameters’ data object is expressed by a class element named \\texttt{GeneralTechParams}. This class is able to define all general technology parameters in Table 4.1 (Technology name, Technology node, Process, Voltage option, Metal option, Resistor capacitance type, Maximum temperature, Minimum temperature, and Design rule manual).\nFigure 4.10 Data model of the specification\n4.3 Reliable Specification Creation Method\n\nThe specification for library development is a collection of information obtained from several information owners and existing references. This specification is traditionally created depending only on the expertise of the specification developers. In addition, a sequence of activities which gathers the information and defines it in the specification is a totally manual work. Unfortunately, no efficient unified method is available to achieve this significantly important work. Moreover, the share-ability and usability of the existing references are very low due to the complex data acquisition from them. For these reasons, the specification reliability highly depends on the attention the specification developers pay to remove specification errors such as inconsistency and incompleteness.\n\nThus, we propose a reference-based method to create a reliable specification by addressing the critical issues of the traditional manual methods for specification creation. Its main ideas are to provide as much predefined information as possible from a centralized reference database and to increase the share-ability and usability of the references. Generally, the specification data can be divided into two parts: one is the information such as PVT corners, slope and capacitive load values which must be given by its owner. Another is the information that can be derived from the predefined documents. Our reference-based method focuses mainly on the second one.\n\n4.3.1 Reference Database\n\nIn Figure 4.9, two types of parameters were introduced. In order to cover them, we propose a reference database that consists of two kinds of references: dictionary and list reference. The dictionary provides the reference relevant to the first type of simple parameters without a key attribute. The list reference provides the reference relevant to the second type of parameters with a key attribute.\n\na) Dictionary\n\nThe dictionary is a collection of terms. Like a semantic dictionary providing all meanings of a term, the proposed dictionary also aims at providing all possible values of the predefined term. Figure 4.11 shows its data model. As shown in this figure, a term enables to encapsulate any parameter information with a name and more than one value.\nBy using this simple and formal representation, most of the shareable data for specification creation can be predefined in the dictionary. Especially, this dictionary permits to cover parameters corresponding to the data model in Figure 4.9 (a) thanks to its similarity. In order to support such data, the list of parameters and all available values of each parameter can be derived from this reference. For example, to define the general technology parameters, their complete list and desired parameter values are required. First, GeneralTechParam term having all parameter names as term values (TechnoNode, Process, VtOption, MetalOption, and so on) may be defined in the dictionary to give a list of general technology parameters. Second, all available values of each parameter may also be given by using this reference. To give an example, TechnoNode term with all its possible values (130nm, 90nm, 65nm, 45nm, 32nm and 28nm) can be defined to provide the information about technology node. In consequence, the specification developers are capable to obtain the complete parameter list from the dictionary. Once having a parameter list, they may retrieve the information about each parameter and then to select desired parameter values to finally define it in the specification. Furthermore, if we need a new parameter or a new parameter value, it is sufficient to add a new term or a new value to the corresponding term. Therefore, the updated information can easily be shared with all users through the dictionary.\n\nb) List reference\n\nThe list reference is proposed to provide a complete parameter set at a time unlike the dictionary based on the repetitive retrieval of the term. This reference covers the tool and view information having the key attribute which corresponds to the data model in Figure 4.9 (b). It offers a complete list of predefined keys with its identification information as described in Figure 4.12.\nAs shown previously, the tool information includes a tool name, version and key attribute. Among them, a couple of tool identification information, which is tool key and its corresponding tool name, is regarded as fixed information. In contrast, the tool version is no fixed information because it must be given by the specification developer. For this reason, the tool list reference must provide only the fixed information as shown in Figure 4.13. As a result, to complete the information for all required tools, it is sufficient to give only the correct tool version for each tool provided by the tool list reference.\n\nTo define the information about Design Compiler tool, its tool key “designcompiler_synthesis” and tool name “synthesis” can be obtained from the tool list reference, whereas the tool version (e.g. “i-2013.12”) must be given by the specification developer.\n\nUsing the same method as to update the dictionary, defining a new tool or a new purpose of an existing tool can be simply added as a new tool element with its specific tool key and corresponding tool name in this reference. Likewise, a view list reference can be made. Finally, these references help to easily and rapidly define complete tool and view information.\n\nTo summarize this subsection, the aforementioned reference database enables the specification developer to create a complete and consistent specification by providing rich predefined information relevant to parameter list, values and identification information. In addition, it also provides several significant benefits. One of them is that enforcing and centralizing the references leads to improve their share-ability and reusability. Another is to provide a unified method to easily extend the specification data via the concerning reference and rapidly apply the updated information to the specification creation. However, when defining a reference, the author must not make an error because it may have a direct impact on all specifications related with this error.\n4.3.2 Specification Creation using a Reference Database\n\nAs mentioned above, the specification data can be created from the dictionary or list references according to the parameter type. Figure 4.14 shows how to gather specification data from the reference database. As shown in this figure, the dictionary-based flow is carried out by parameter list acquisition and parameter value selection based on the repetitive retrieval. On the contrary, the list reference-based flow is accomplished by parameter list acquisition and parameter value entry. The specification developers can easily define all specification data to produce a final specification through these flows.\n\n![Diagram of Specification Creation using a Reference Database]\n\nFigure 4.14 Specification creation using a reference database\n\n4.4 Efficient Method for Data Extraction from the Specification\n\nFor library development, the library developers must extract the necessary data from the specification. However, there is unfortunately no effective data extraction method to meet their needs due to the absence of a complete specification. One of the most important needs is to precisely get the desired data from the specification. Another is to obtain a complete set of data for performing the library development task.\nTo address these needs, we propose the keyword for precisely identifying the data and task-based keywords for selectively extracting all necessary data for the target task. These proposed methods are introduced in the following subsections.\n\n4.4.1 Keyword for Precise Data Identification\n\nAs described in Figure 4.10, the specification represents a hierarchical structure to cover a variety of data. To extract data from this specification, we must first find which branch contains the desired data in the tree structure and then identify it. The library developer usually needs a part or whole set of data from the corresponding data group. For example, for the characterization of standard cells, we need a SPICE simulator, design kit and characterization tool as a part of tools and a whole set of PVT corners for the standard cell library. In order to satisfy such needs, we propose to use a keyword that consists of tuple of elements given by:\n\n\\[\n\\text{Keyword} = (\\text{Parameter}, \\text{Category}, \\text{Name or Key}, \\text{Id})\n\\] \n\n(4.1)\n\nWhere:\n\n**Parameter**: identifies the target parameter.\n\n**Category**: identifies the category of parameter such as library category. It is required only for the categorized parameter set.\n\n**Name or Key**: identifies one parameter. According to the kind of parameter, either name or key should be given.\n\n**Id**: identifies the parameter value. When the parameter has more than one value, each value can have its specific id to differentiate one from another.\n\nThis keyword provides the key information to search data in the specification. Specifically, **Parameter** and **Category** elements permit to select a set of parameters. In addition, **Name or Key** element permits to identify one parameter from the selected parameter set. If selecting one parameter with its specific value, **Id** element must also be given.\nFigure 4.15 Data extraction with keyword\n\nFor example, two keywords are given as follows:\n\n1) **Keyword1** = (Parameter = GeneralTechParams)\n2) **Keyword2** = (Parameter = Tools, Key = designcompiler_synthesis)\n\nThe first keywords give only GeneralTechParams as Parameter element value. It means that the given element identifies the total set of general technology parameters as described in Figure 4.15. The second keyword gives two elements’ values: Tools and designcompiler_synthesis. The first one represents the Parameter element and the second one the Key. These values indicate Design Compiler tool in the tool set as depicted in Figure 4.15. As a consequence, the keywords enable to know where the desired data are located in the specification to selectively access them.\n\n4.4.2 Task-based Keywords for Efficient Data Extraction\n\nThe tasks for library development necessitate various data from the specification. The library developer must collect them before executing each task. However, this data preparation is a bottleneck in library development because he has difficulties in collecting only data relevant to the target task. To address these difficulties, we propose task-based keywords that enable to get the required data for executing a task without having knowledge about the relationship between the task and specification data. For this purpose, we must first\nexplicitly define this relationship. However, no way is available to efficiently represent it so far. The aforementioned keywords are therefore used for the relationship definition.\n\nIn order to identify all data related to a task, several keywords can be given by:\n\n$$Keywords_{\\text{Task}} = \\bigcup_{i=1}^{m} Keyword_i = \\bigcup_{i=1}^{m} (Parameter_i, Category_i, Name_i, or Key_i, Id_i)$$\n\n(4.2)\n\nWhere: $m$ is the number of necessary keywords\n\nThese keywords permit to link the task with specification data. For instance, to define the relationship between the timing model generation for standard cells and a collection of specification data including a set of PVT corners, design kit, etc., the keywords can be given as follows:\n\n$$Keywords_{\\text{TIMING.MODEL GENERATION}} = \\bigcup_{i=1}^{m} Keyword_i$$\n\n$$= (Parameter = \\text{PVT}, Category = \\text{STDCELL})$$\n$$\\cup (Parameter = \\text{Tool}, Key = \\text{designkit})$$\n$$\\cup \\ldots$$\n$$\\cup (Parameter = \\text{View}, Key = \\text{timinglib_timinganalysis})$$\n$$\\cup (Parameter = \\text{View}, Key = \\text{timingdb_timinganalysis})$$\n$$\\cup (Parameter = \\text{SoCDesignFlow}, Name = \\text{FrontEnd})$$\n$$\\cup (Parameter = \\text{SoCDesignFlow}, Name = \\text{SignOff})$$\n\nThe first keyword represents a set of PVT corners for standard cells. The second one represents a design kit. These data are needed to perform the timing model generation. Unlike these keywords, the four last keywords are also given to specify the views and design flows related to the task. Specifically, the timing model generation task relates to the creation of the Liberty library (.lib) and the compiled library (.db). In addition, these views are required for Front-End and Sign Off stages in the SoC design flow. Consequently, we can easily define the relationship between the tasks and specification data by using keywords.\n\n4.5 Validation of the Specification\n\nThe reference-based method may help to reduce possible specification errors by providing the predefined information such as parameter list and available parameter values\nduring the creation of the specification. However, it is difficult to guarantee the correctness of the information determined by specification developers. For this reason, after its creation, a post-validation is highly required to ensure the reliability of the information. Thus, two methods are discussed in this subsection.\n\n1. **Using the relationship of data objects**\n\n ✓ Consistency check of specification data\n\n As mentioned above, the relation between the independent data objects were created by their common element so that the check can be carried out by verifying this element. For instance, we can verify if the slopes are well defined for all PVT corners by comparing the given PVT names in PVTs data object with those of Characterization Parameters data object for the consistency check. To illustrate another important example, Design Flows data object can be linked to Tools and Views data objects via ToolKey and ViewKey respectively as described in Figure 4.6. Performing a design step requires at least one view and one tool. Thus, more than one concerned ToolKey and ViewKey for each step must be defined. It permits to check the consistency of the tool and view information from the point of view of the design flow. In other words, we can verify if all tool and view information is well defined in the specification to support all required design flows.\n\n2. **Using the rule**\n\n ✓ Correctness check of identifier naming\n\n We presented the name element and key attribute to identify a parameter. To assign them in a unified way, the naming rule must be determined. For example, the PVT name is a concatenation of all essential elements of PVT corner like ‘Process_Voltage_GND_Temperature_Age’. According to this naming rule, a PVT name should be given for each PVT corner. After finishing the definition of all PVT corners, their name must be verified according to this rule.\n\n ✓ Correctness check of the parameter value\nThe parameter value verification is a delicate and complex task because it inevitably requires the deep analysis on the characteristics of parameter value. Firstly, we should check the data type of parameter value. For instance, the data type of slopes and capacitive loads should be checked as a positive float. Secondly, the given parameter value can be verified by using the rule to determine its value. For example, the tool version is differently assigned according to the strategy of the tool developer as shown in Figure 4.16. Since the tool version given by the specification developer may create compatibility problems due to wrong versioning, we need to verify it to provide the correct one. One of the solutions is to compare the tool version of the new specification with that of the previous one as a reference to detect an error. It can be performed by checking if it is greater than or equal to the previous one because the tool version tends to increase numerically or alphabetically when updating the specification.\n\n\n\nFigure 4.16 (a) simple tool versioning with numerical increment (b) simple tool versioning with numerical and alphabetical increments (c) complex tool versioning\n\n### 4.6 Validation of the Library against the Specification\n\nThe generated library package must be verified before its delivery to customers in order to ensure its quality. The most efficient and effective way to validate the library is to check it against the specification given for its production.\nAs given in Table 4.2, the library checklist consists of three checks: completeness, compatibility and correctness.\n\n- **Completeness of the library**\n\n The library views should be created according to the lists of library views and PVT corners provided by the specification. Thus, the completeness of the library can be achieved by simply verifying if all required library views exist on the given view path.\n\n- **Compatibility between the library view and CAD tool**\n\n The library package must provide system designers with a complete set of library views to support their design flow. When using library files, they should not have compatibility problems with CAD tools. It means that their syntax must be correct to be readable by the tools. Such problems can be detected by reading each library file with CAD tool given in the specification.\n\n- **Correctness of the library view**\n\n The correctness check verifies the library view with respect to its syntax but not contents. One of the ways to verify the correctness of the library view is to check if its specific attributes provided by the specification are correctly defined. Now, there are only view attributes for Liberty library.\n\n### 4.7 Conclusion\n\nIn this chapter, we have proposed an appropriate data model to represent the specification containing all target information from technology-dependent parameter to design flow information. To efficiently cope with these specification data, we also introduced\ntwo approaches from two different perspectives: specification developers and library developers. One is the reference-based method to create a complete and consistent specification having a huge amount of data. Another is the task-based keywords to quickly and precisely extract the desired data from the proposed specification according to the target task. Finally, the validations for the specification and the library have also been discussed. In the next chapter, we present an XML-based specification language to represent our target specification as well as a specification platform to efficiently deal with it by the proposed methods.\n5. Specification Platform\n\nContents\n\n5.1 Introduction ............................................................................................................... 71\n5.2 LDSpecX: Library Development Specification based on XML ............................... 72\n5.3 Specification Creation Tool....................................................................................... 73\n 5.3.1 XML-based Reference Database ........................................................................ 74\n 5.3.2 User-friendly GUI for Specification Creation .................................................... 76\n a) Specification creation flow ................................................................................. 76\n b) User-friendly GUI .............................................................................................. 78\n5.4 API for Specification Data Extraction ....................................................................... 82\n 5.4.1 Library Development Task Definition ............................................................... 82\n 5.4.2 Specification Data API ....................................................................................... 84\n 5.4.3 Library Verification Tool using the API ............................................................ 86\n5.5 Conclusion ................................................................................................................. 87\n\n5.1 Introduction\n\nThe previous chapter was dedicated to analyze the specification data for library development and then to propose a suitable data model for representing it. Additionally, two methods were introduced to create a complete and consistent specification and to precisely extract data from it according to the target task. In addition to these methods, the verifications of the specification and library were also presented.\n\nIn this chapter, we first present an XML-based specification language to encapsulate all required information for library development by using the proposed data model. Then, we introduce a specification platform that consists of several tools for creating specifications, extracting data and verifying the library.\n5.2 LDSpecX: Library Development Specification based on XML\n\nIn the previous chapter, we presented a hierarchical data model to encapsulate a variety of data. By using it, we would like to propose an XML-based specification. One of the most interesting features of XML is machine-readability. It enables to transmit data to the library development system. In other words, the automation of data processing is easily achievable. Furthermore, the specification language facilitates building a database and dealing with it thanks to the unified format. From the conceptual data model in the previous chapter, Library Development Specification based on XML (LDSpecX) was proposed [108]. This specification language allows defining all necessary information in a unique XML file. Figure 5.1 shows its schema which corresponds to that in Figure 4.10. This XML schema represents the structure of our XML-based language and details the syntax and semantic rules. Specifically, LDSpecX provides seven top level elements that correspond to the data objects in Figure 4.6 respectively: GeneralTechParams, SpecificTechParams, PVTs, CharacParams, Tools, Views and DesignFlows. In order to create a complete specification, the specification developers must define all indispensable parameters of every top level element using LDSpecX. Additionally, the identifier attributes of the specification namely LDSpecXName and LDSpecXversion should also be given.\n\n\nTo illustrate an example of the top level elements, the schema of \\texttt{GeneralTechParams} element is described in Figure 5.2. This schema details the organization of the sub-elements and attributes. In addition, it can define the data type and the number of element.\n\n\n\nFigure 5.2 Schema of GeneralTechParams element\n\nFigure 5.3 shows an example of defining a technology node named \\texttt{TechnoNode} in the \\texttt{GeneralTechParams} element. It should be in accordance with its syntax given in Figure 5.2.\n\n```xml\n<GeneralTechParams>\n <GeneralTechParam>\n <GeneralTechParamName>TechnoNode</GeneralTechParamName>\n <GeneralTechParamValue>28</GeneralTechParamValue>\n </GeneralTechParam>\n ...\n</GeneralTechParams>\n```\n\nFigure 5.3 Example of GeneralTechParams element\n\nIn the same way, the whole schema of LDSpecX was defined in detail. It becomes the foundation of the proposed XML-based specification language. Furthermore, the well-defined XML schema can be used to validate the resultant XML document with Document Object Model (DOM) parser or Simple API for XML (SAX) parser with respect to the syntax. As a result, it helps to verify the completeness and correctness of the specification in LDSpecX.\n\n### 5.3 Specification Creation Tool\n\nNow, the specifications for advanced technology such as 28nm Fully Depleted Silicon-on-Insulator (FDSOI) CMOS contain several thousand parameters. Especially, the development of manufacturing and design methodologies may lead to increase the number of\nsuch parameters. We have to define all these parameters using our XML-based specification language. However, although there are some useful editors to create XML documents like Oxygen XML editor [114], they are not suitable to enter a large amount of data because all data should be entered manually. Thus, we highly need an appropriate tool support to efficiently create an LDSpecX-based specification.\n\nThis section describes a specification creation tool based on the reference-based approach to create a complete and consistent specification [115]. It splits into two parts: XML-based reference database construction and user-friendly graphic user interface (GUI) development. This GUI enables specification developers to create specifications in LDSpecX with the help of the reference database.\n\n### 5.3.1 XML-based Reference Database\n\nIn the previous chapter, we presented two types of references to provide as much predefined information as possible for specification creation: dictionary and list reference. First of all, the reference database containing these references should be constructed. In this thesis, in order to deal with data in a unified way, this database is also created by using XML.\n\nFirstly, the schema of dictionary was made from its data model described in Figure 4.11. The resultant schema is represented in Figure 5.4.\n\n\n\nTo illustrate how to define terms in the dictionary, Figure 5.5 gives the definition of two terms. The first one represents a list of general technology parameters. The second one gives all available values of the technology node as a general technology parameter. As explained previously, we can obtain the information about the parameter list as well as parameter values from this reference.\nSecondly, the schemas of two list references for the tool and view have been made from their own data model. Figure 5.6 describes the schema of tool list reference. As depicted in this figure, the tool list reference can have more than one tool element having a tool key attribute and a tool name.\n\nFigure 5.6 Schema of tool list reference\n\nFigure 5.7 gives an example of the tool list reference. This example includes two tool elements for Design Compiler and an in-house tool named alto for the cell characterization.\n\nFigure 5.7 Example of a tool list reference\nFinally, all necessary references were created by using XML according to their proposed syntax. As a consequence, the XML-based reference database could be made up of these references.\n\n5.3.2 User-friendly GUI for Specification Creation\n\nAs mentioned above, most of XML documents are created entirely manually with text editors. However, in our case, it is very difficult to use such existing tools for creating our XML-based specification due to its high complexity. Thus, we intend to develop an appropriate tool to create an LDSpecX-based specification. For this purpose, a systematic and unified flow has first been proposed by using the reference database and then a user-friendly GUI was developed.\n\na) Specification creation flow\n\n\n\nFigure 5.8 Reference-based specification creation flow\nTo begin with, the reference-based specification creation flow is described in Figure 5.8. This flow is divided into two main steps: fragment creation and specification creation.\n\n**Definition**\n\n**Fragment**\n\nA fragment represents a section of the specification. This fragment corresponds to the top-level element containing parameters of the same category.\n\n**Fragment creation**\n\nThe fragment creation step can be accomplished by four sub-steps: fragment selection, data entry page creation, data entry and fragment check.\n\n- **Fragment selection**: The specification must split into several fragments because the specification data should be gathered from several persons according to the data category or different schedules. In other words, the specification creation is a collaborative work. Thus, the specification developers should select one or more concerning fragments to define the desired parameters.\n\n- **Data entry page creation**: If the fragment is selected, the specification tool acquires its parameter list from the reference database and then the data entry page is dynamically created by the obtained parameter list.\n\n- **Data entry**: The specification developer enters data on the data entry page with the help of the reference database.\n\n- **Fragment check**: The entered data are stored in a split XML file for each fragment. The fragment file must be checked for the syntax and completeness. The syntax check validates the created XML file against the schema of the corresponding fragment by using DOM parser. The completeness check verifies if all parameters have at least one value.\n\n**Specification creation**\n\nTo start the specification creation step, the fragment creation step should be repeated until all required fragments are created. Then, this step can be carried out by fragment combination and specification check.\n- **Fragment combination**: In this step, all created fragment files are merged into an LDSpecX-based specification file by using an XSLT template and XSLT processor [110].\n\n- **Specification check**: After the fragment combination, we need to verify the created specification. The specification check covers not only the syntax and completeness but also the consistency and correctness. The syntax check can be performed by validating the specification against the schema of LDSpecX with DOM parser. The completeness check verifies if all fragments are given in the specification. On top of that, the consistency and correctness check are also added to verify the information in the specification as proposed in the previous chapter. Finally, the LDSpecX-based specification can be validated thanks to these checks. It significantly aids to guarantee the specification reliability by comparison with its verification dependent only on the specification developers.\n\nb) **User-friendly GUI**\n\nIn order to support the aforementioned flow, a user-friendly GUI was developed in Python [109]. The GUI facilitates the creation of the LDSpecX-based specification.\n\n\n\nFigure 5.9 (a) Specification information entry window (b) Fragment selection window\n\nFirstly, it can start with its name and version definition on the specification information window in Figure 5.9 (a). Then, the proposed GUI provides a fragment selection window as\nshown in Figure 5.9 (b). Each specification developer is able to choose the desired section of the specification by simply selecting one or more target fragments. According to the selected fragments, the corresponding data entry pages having its parameter list obtained from the reference database will be created. The data entry pages provide facilities to access the references and to enter data. As we introduced the aforementioned specification creation flows based on the dictionary and list references in Figure 4.14, there are two types of fragments according to these flows. The data page of each type of fragment can be built by using its related reference.\n\n\n\nFigure 5.10 Data entry page of GeneralTechParams fragment\n\nTo illustrate an example of the first type of fragment, the data entry page of General Technology Parameters fragment is shown in Figure 5.10. The list of general technology parameters can be obtained from the dictionary and then given on the data page. To define each parameter, there are two ways. First, the `find` button allows accessing the dictionary to get all possible parameter values from it by retrieval. The specification developer can select\nthe desired values among them. For instance, all possible technology nodes can be displayed on the dictionary window by clicking the **find** button as described in this figure. Then, we can select one of them to give a technology node. Second, if the dictionary does not contain the desired parameter value, a new value must directly be entered in the entry. If all parameters are defined with these methods, the **create&check** button permits to create the fragment file and to check it with respect to the syntax and completeness.\n\nFigure 5.11 shows the data entry page of tool list fragment as the second type. This fragment requires a complete list of tools. Thus, this list must be derived from the tool list reference in order to construct its data entry page. Unfortunately, due to its limited space, only tool keys are displayed. However, clicking each tool key button allows showing its identification information such as tool name. To complete this fragment, the appropriate tool version for all tool keys must be given. Likewise, the **create&check** button creates the XML file and verifies the resultant fragment file.\nFigure 5.12 describes the specification creation page. The create button at the bottom allows finding all created fragment files and creating an LDSpecX-based specification by merging them. After the specification creation, the check button permits to check the specification file for its syntax, completeness, consistency and correctness.\n\nAs described above, the parameters to define in the specification rely greatly on the references because the data entry page provided by the GUI is flexibly established depending on which parameters are derived from the reference database. In other words, the proposed GUI can be customized by the specification developers by simply updating the references. For this purpose, it also offers the end-users the ability to access the reference and to update it. For instance, Figure 5.13 shows the dictionary edit page. As shown in this figure, all terms of the dictionary are listed in the left box. After selecting the desired term name, all possible term values will be displayed in the right box by clicking the Get Value button. The entry\nboxes at the bottom of the page are provided to add a new term or a new term value to the dictionary. It enables to enrich the dictionary.\n\nFigure 5.13 Dictionary edit page\n\n5.4 API for Specification Data Extraction\n\nThis section introduces a simple API for data extraction from the LDSpecX-based specification. It depends on the keywords to identify specification data as proposed in the previous chapter.\n\n5.4.1 Library Development Task Definition\n\nThe specification creation was presented previously by using GUI. It corresponds to the specification phase in the library development process. Since the specification is now available, the library developers are able to perform the subsequent phases from design to validation. Each phase can be divided into several steps that represent a sequence of tasks. For\nexample, the design phase contains Front-End (FE) and Back-End (BE) view generation steps. The FE view generation step contains a timing model generation task. This task can be performed by timing characterization and timing modeling. However, the granularity of the task may be different according to the library category because the methods to perform the task depend on the features of the library cell. For instance, the cell characterization method is not the same for standard cells as that for memories. As a result, the required specification data depends on the library category. Thus, we need to define the library development tasks for each library category separately. Figure 5.14 (a) visualizes the schema of the library development flow. As shown in this schema, we can differentiate a set of steps by the library category. Furthermore, as mentioned earlier, a wide range of specification data is required for executing the task and thus, the task-based keywords were proposed in the previous chapter. Figure 5.14 (b) shows how to define the relationship between task and data by using these keywords. This element may have more than one selector element, which permits to encapsulate task-based keywords.\n\n\n\nTo give an example of the task definition, Figure 5.15 represents how to define a timing model generation task for standard cell library by using selectors to identify the specification data. In this example, the first selector gives keywords to identify a set of PVT\ncorners for standard cell library. The second and third selectors give keywords to identify a characterization tool and tool configuration parameters for timing characterization respectively. In the same way, all library development tasks over library categories can be predefined as a function of keywords and stored in an XML file.\n\n```xml\n<LibDevFlow>\n <StepList>\n <LibCategory>STDCELL</LibCategory>\n <Step StepName=\"FE_VIEW_GENERATION\">\n <Task TaskName=\"TIMING_VIEW_GENERATION\">\n <Selector parameter=\"PVT\" category=\"STDCELL\"/>\n <Selector parameter=\"Tool\" key=\"alto_charac\"/>\n <Selector parameter=\"ToolConfigParam\" category=\"TIMING_Charac\" key=\"alto_charac\"/>\n </Task>\n </Step>\n </StepList>\n</LibDevFlow>\n```\n\nFigure 5.15 Example of a library development flow for standard cell library\n\n5.4.2 Specification Data API\n\nThe specification data API was developed in Perl [111]. This API allows accessing the LDSpecX-based specification database to obtain data from it as described in Figure 5.16. In order to apply the proposed method, the aforementioned library development flow was written in an XML file.\n\nFigure 5.16 Overview of the API\nThe API provides two fundamental functions as follows:\n\n1) \\texttt{getSpecData} (specification, keyword): returns data (list of strings) derived from the selected LDSpecX-based specification (XML file) by using the given keyword (string).\n\n2) \\texttt{getFlowInfo} (library category, task): returns keywords (list of string) from the library development flow according to the given library category (string) and task (string).\n\nAdditionally, by using these functions, a function to extract data depending on the desired task is also provided as below:\n\n3) \\texttt{getSpecDataViaFlow} (specification, library category, task): returns all necessary data (list of string) from the LDSpecX-based specification (XML file) for the target task (string).\n\nFigure 5.17 describes the data extraction flow by using the task-based keywords. First, the keywords are gathered from the flow file. Second, by using these keywords, the data are derived from the specification database.\n\n\nTo give an example of using the task-based keywords, the library developer needs the tool information for executing a task. At STMicroelectronics, tools’ name and version should be written in a specific file named `.ucdprod` that is employed to load them. However, when such information is collected manually without knowing the required tools for a target task, redundant tools can be given in this file. As a result, it may cause a compatibility problem when loading them at the same time. On the contrary, by using the proposed method, we can get only minimal necessary tools. Thus, it not only gets tool information in an efficient way but also addresses the compatibility problems.\n\nIn summary, the API offers efficient functions for data extraction according to the needs of library developers. Fundamentally, it permits any user to selectively extract the desired data by giving a keyword. In addition, the task-based keywords permit to precisely identify only the data needed for executing the chosen task and quickly get them. Therefore, it is very useful for library developer to accomplish his tasks without having a good understanding of the relationship between the specification data and library development task.\n\nFurthermore, the data extracted from the given specification for task execution often need to be rewritten in accordance with the specific syntax of the tool. In order to automate this process, we also developed specific generators in Perl integrating the functions provided by the API into them. These generators facilitate to produce the machine-readable files where specification data are given. Thus, they enable library developer to accomplish his target task more smoothly. For example, in order to automatically generate the aforementioned file (`.ucdprod`), a generator named `genucdprod` was developed. It allows extracting the tool information by using the API according to the selected target and rewriting it by following its syntax.\n\n### 5.4.3 Library Verification Tool using the API\n\nAs stated in the previous chapter, three basic checks against the specification were remarked: completeness, compatibility and correctness.\n\nThe compatibility check can be performed using the existing library verification tool and the tool information obtained by the API. On the contrary, for completeness and correctness checks, we have to develop a verification tool because the existing one is not able to cover them. Thus, a supplementary verification tool was developed in Perl. It aims at\nverifying the resultant library against the specification with respect to the completeness and correctness. The verification can be achieved by deriving the specification data related to each check as given in Table 4.2 via the API. The completeness check needs a library view list and PVT corners for the related library category. The correctness check requires attributes of the generated library view. Finally, this tool may improve the quality of the library by enforcing the library check against the specification. Additionally, this tool also shows how to apply the capabilities provided by the API.\n\n5.5 Conclusion\n\nIn this chapter, we have presented an XML-based specification language named LDSpecX to represent the specification for library development. Furthermore, an LDSpecX-based specification platform was introduced by using the methods proposed in the previous chapter. This prototype consists of two main components: a specification creation tool with user-friendly GUI and a specification data API. In the next chapter, we demonstrate the development of a standard cell library from an LDSpecX-based specification by using the developed specification platform.\n6. Experiments\n\nContents\n\n6.1 Introduction ............................................................................................................... 88\n6.2 Library Development from the Specification ............................................................ 88\n 6.2.1 Specification Creation ................................................................................ 88\n 6.2.2 Library Development from the Specification ............................................. 91\n6.3 Evaluation .................................................................................................................. 95\n 6.3.1 Specification Evaluation against Five Requirements ................................... 95\n 6.3.2 Specification Data Processing .................................................................... 96\n6.4 Conclusion ................................................................................................................. 97\n\n6.1 Introduction\n\nWe have presented in the previous chapter a XML-based specification language named LDSpecX. This specification language enables specification developers to define all necessary information for library development. Furthermore, a specification platform was developed to collaboratively create a complete and consistent specification as well as to efficiently extract specification data from it.\n\nThis chapter introduces the development of a standard cell library by using the proposed specification platform. Experimentally, a specification with 28nm FDSOI CMOS technology is first created in LDSpecX through the GUI. Then, we show the development of a standard cell library from this specification by using the API. Thus, a standard cell library is developed according to the library development process from the specification creation to the library validation presented in the chapter 2.\n\n6.2 Library Development from the Specification\n\n6.2.1 Specification Creation\n\nThe specification must provide every library developer with complete information to develop his target libraries or IPs. The specification data may increase by the supported\nlibrary categories. For example, we need a set of PVT corners for each supported library category such as standard cell library and I/O library. In these experiments, we focus only on the standard cell library to reduce the quantity of data. The specification for developing a standard cell library with 28nm FDSOI CMOS technology was created by using LDSpecX with the help of the GUI of the specification platform according to its process presented earlier.\n\nThe specification creation phase can be achieved by the fragment creation and fragment combination. Firstly, we create all fragments of the specification. To create each fragment, the information about its parameters is gathered from the reference database as well as information owners. After consecutively creating all necessary fragments, they are merged into a specification in LDSpecX. Then, the created specification is verified.\n\nFigure 6.1 Screenshot of specification check report\nIn conclusion, the target specification was created and checked via the GUI. Figure 6.1 shows the obtained check report for five checks: specification creation, completeness, syntax, consistency and correctness. The first check has verified the existence of the specification file. The completeness check has identified all included fragments. The syntax check has validated the LDSpecX file against its schema by using DOM parser. The consistency check has verified the consistency between PVTs fragment and CharacParams fragment via PVT name and that between Tools, Views and DesignFlows fragments via key attributes. Finally, the correctness check has verified the PVT name and tool version by using their rule.\n\nThe resultant specification is compared with the traditional specifications that were indeed written in natural language and tabular form by design platform developers. The comparison results are given in Table 6.1. These results show the effectiveness of the proposed GUI.\n\nFirst, the total time consumed by the proposed method for the specification creation is around 42 minutes. It is about 3 times faster than by traditional manual method even if much more specification data were dealt with. This is the reason why the traditional methods to define specifications depends entirely on human intervention. On the contrary, our user-friendly GUI allows a high reduction of human interventions by providing many facilities to enter data and to get the information from the reference database.\n\nSecond, these results also show that LDSpecX permits to provide richer information than the traditional methods having missing parameters that are individually stored outside the specification or are in the knowledge of library developers. These missing parameters such as tool configuration parameters may provide abilities to allow the automatic tool configuration without the help of tool developers.\n\nFinally, even if it is difficult to quantitatively estimate the human-errors, the reduction of potential errors may also be expected thanks to a unified specification instead of several scattered ones and a centralized reference database. In addition, the specification verification tool support also aids to reduce error like inconsistency.\n### Table 6.1: Comparison of LDSpecX-based specification and traditional specifications\n\n<table>\n<thead>\n<tr>\n<th>Information Category</th>\n<th>Parameter</th>\n<th>Number of parameters</th>\n<th>Traditional specifications</th>\n<th>LDSpecX</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Technology</td>\n<td>General Technology Parameter</td>\n<td>6</td>\n<td>9</td>\n<td></td>\n</tr>\n<tr>\n<td>Technology</td>\n<td>Specific Technology Parameter</td>\n<td>6</td>\n<td>6</td>\n<td></td>\n</tr>\n<tr>\n<td>Technology</td>\n<td>PVT</td>\n<td>20</td>\n<td>20</td>\n<td></td>\n</tr>\n<tr>\n<td>Characterization Parameters</td>\n<td>Characterization reference</td>\n<td>-</td>\n<td>13</td>\n<td></td>\n</tr>\n<tr>\n<td>Characterization Parameters</td>\n<td>Slope</td>\n<td>240</td>\n<td>240</td>\n<td></td>\n</tr>\n<tr>\n<td>Characterization Parameters</td>\n<td>Capacitive load</td>\n<td>1136</td>\n<td>1136</td>\n<td></td>\n</tr>\n<tr>\n<td>Tools</td>\n<td>Tool</td>\n<td>73</td>\n<td>76</td>\n<td></td>\n</tr>\n<tr>\n<td>Tools</td>\n<td>Tool Configuration Parameter</td>\n<td>-</td>\n<td>449</td>\n<td></td>\n</tr>\n<tr>\n<td>Views</td>\n<td>View</td>\n<td>154</td>\n<td>154</td>\n<td></td>\n</tr>\n<tr>\n<td>Views</td>\n<td>View Attribute</td>\n<td>10</td>\n<td>10</td>\n<td></td>\n</tr>\n<tr>\n<td>Design Flows</td>\n<td>SoC Design Flow</td>\n<td>3</td>\n<td>3</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>Total number of parameters</strong></td>\n<td></td>\n<td><strong>1648</strong></td>\n<td><strong>2116</strong></td>\n<td></td>\n</tr>\n<tr>\n<td>Number of files</td>\n<td></td>\n<td>2 excel files (5 spreadsheets), 3 word files</td>\n<td>1 xml file</td>\n<td></td>\n</tr>\n<tr>\n<td>Creation time</td>\n<td></td>\n<td>2 hours</td>\n<td>42 minutes</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n### 6.2.2 Library Development from the Specification\n\nWith the created specification, we can perform the next steps for library development. We develop a standard cell library by using the developed API. In addition, as mentioned at the beginning of the thesis, we focus only on the cell-independent information so that the number of cells is not meaningful. For this reason, even though a standard cell library generally contains several hundreds of cells, we used a small set of cells that consist of 11 combinational and sequential ones for our experiment. Likewise, only three of the twenty PVT corners in the given specification are used to minimize the repetition of tasks. Furthermore, we aim at generating all required library views to support the entire design flow for Cadence and Synopsys. In these experiments, the library development starts with FE view generation by using BE database of the library including layout, Spice netlist and so on. Table 6.2 summarizes the target tasks with the specification data as input and the library views as\noutput for developing our test library. In consequence, it can be considered as a scenario of these experiments.\n\nTable 6.2: Summary of input and output for library development tasks\n\n<table>\n<thead>\n<tr>\n<th>Library development flow</th>\n<th>Task</th>\n<th>Input</th>\n<th>Output (library views)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td>Data group</td>\n<td>Specification data</td>\n</tr>\n<tr>\n<td>Design phase</td>\n<td>Technology</td>\n<td>• General technology parameters</td>\n<td>.lib files</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Specific technology parameters</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• PVT corner list</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Characterization references</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Tools</td>\n<td>• Characterization tool</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Spice simulator</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Design kit</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Tool configuration parameters for</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>timing/power characterization</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Views</td>\n<td>• Liberty view attributes</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Technology</td>\n<td>• General technology parameters</td>\n<td>.lib.gz files</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Specific technology parameters</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• PVT corner list</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Characterization References</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Tools</td>\n<td>• Characterization tool</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Spice simulator</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Design kit</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Tool configuration parameters for</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>timing/power characterization</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Views</td>\n<td>• Liberty view attributes</td>\n<td></td>\n</tr>\n<tr>\n<td>Library verification phase</td>\n<td>Completeness check</td>\n<td>Technology</td>\n<td>PVT corner list</td>\n</tr>\n<tr>\n<td>---------------------------</td>\n<td>--------------------</td>\n<td>------------</td>\n<td>----------------</td>\n</tr>\n<tr>\n<td>Correctness check</td>\n<td>Tools</td>\n<td>Library verification tool</td>\n<td></td>\n</tr>\n<tr>\n<td>Views</td>\n<td>View list</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Liberty view attributes</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n---\n\n1 These reports give the check results of the library but are not included in the library package.\nAccording to the flow described in Table 6.2, all tasks were executed to produce the rest of the contents of the library. All necessary specification data for each task are given in this table. By using the aforementioned generators, the necessary input data were derived from the given specification and the tool input files could be produced with obtained data. For example, NLDM timing/power model generation requires technology parameters, tool parameters and view attributes as shown in Table 6.2. To execute this task, two tool input files are required. The first file (.ucdprod) gives a characterization tool, Spice simulator and a design kit with their proper version to load them correctly. The second file includes all technology parameters, tool configuration parameters and view attributes so as to provide process parameters for cell characterization and to set up the configuration of the characterization tool. These input files could be generated by using their specific generator.\n\nDuring design and derivation phases, 86 library views were obtained to produce a complete library package. This library package must be verified. Thus, the library verification tool based on the functions of the API is used to achieve this objective. This verification phase consists of the following:\n\n- Firstly, the library package is checked if it contains all mandatory library views. Using PVT corner list and view list derived from the specification, the complete view list could be reestablished. The library is checked by comparison with this view list. For instance, Liberty library containing both timing and power models has to be made for each PVT corners. As mentioned above, we use three PVT corners (ff28_1.30V_0.00V_125C, tt28_0.92V_0.00V_25C, ss28_0.80V_0.00V_125C). As a result, the final library package must be checked if it includes as many views as the number of PVT corners as described below:\n\n a) C28SOI_SC_12_CORE_LR_ff28_1.30V_0.00V_125C.lib \n b) C28SOI_SC_12_CORE_LR_tt28_0.92V_0.00V_25C.lib \n c) C28SOI_SC_12_CORE_LR_ss28_0.80V_0.00V_125C.lib\n\n- Likewise, the correctness check is carried out by using the view attributes obtained from the given specification. In these experiments, only Liberty view attributes were dealt with. However, according to the availability of the view attributes in the specification, this check may be extended to cover other views.\nFinally, the standard cell library including a complete set of views is developed and checked with the LDSpecX-based specification. By using our method, the total time consumption to extract data for all tasks is approximately inferior to 3 minutes compared to 4 hours by using the traditional (semi-manual) method. In addition to the time saving, the proposed method allows to interactively extract the desired data whereas the traditional one does not permit it.\n\n6.3 Evaluation\n\nA standard cell library was experimentally developed to evaluate the LDSpecX-based specification and its platform.\n\n6.3.1 Specification Evaluation against Five Requirements\n\nIn the chapter 4, the requirements of the specification for library development were discussed to propose a novel specification instead of the current ones. Now, we need to verify whether the LDSpecX-based specification coincides with them.\n\n- **Formality**: LDSpecX as an XML-based language allows to unify forms of the current specifications that represent the combination of natural language and tabular forms. In addition, this data model enables to represent the specification encapsulating a large variety of data in a unified way. We are thus able to define more than two thousands parameters by using LDSpecX.\n\n- **Consistency**: In the data model of LDSpecX, the duplication of data is minimized except for the common elements like PVT name to represent the relationship between data. At the end of the specification creation, we have also checked the consistency of these common elements by the help of the checks provided by the platform. In addition, since the specification platform provides every specification developer with the same information from a unique reference database, it may help to ensure the consistency of the specifications.\n\n- **Completeness**: The completeness can be evaluated from two points of view: missing parameter and missing parameter value. Firstly, since we get a complete list of parameters from the reference database, there are few possibilities to have missing parameters. Secondly, the prototype provides the completeness check at the end of\neach step (fragment creation and specification creation) while creating a specification. Fundamentally, this check verifies whether each parameter has at least one parameter value. Consequently, a standard cell library has been successfully developed with the given specification. It shows that the created specification in LDSpecX is complete to provide all information for library development.\n\n- **Extensibility:** The extensibility must be guaranteed because it is one of the most important requirements for increasing data of the specification. The prototype proposes two ways to extend specification data. One is to enrich the references so that we can get more parameter information from them. Another is to provide possibilities to define as many parameters as you need. In the case of PVT corner, it tends to increase with the evolution of manufacturing technology as shown in the chapter 2. Thus, these parameters can be totally given by the specification developer.\n\n- **Unambiguity:** The information defined in the traditional specification may be ambiguous for library developers because each part can be made by different person with his own method and knowledge. For this reason, different users could interpret it differently. To address this issue, all references are centralized in a unique repository shared with all specification developers. In addition, XML language encapsulates data in tags which can also help to easily comprehend the contained information.\n\n### 6.3.2 Specification Data Processing\n\nThe main goal of the prototype is to improve the existing automatic system for library development by the top-down approach that smoothly translates data from the specification to the system throughout the entire process. Indeed, a complete and consistent specification for standard cell library with 28nm FDSOI CMOS technology was created using LDSpecX via the GUI of the prototype. Then, a sequence of all necessary tasks for library development was successfully accomplished with the help of the generators based on the API. These tools allowed us to quickly and automatically generate tool input files containing necessary specification data for the target task. Consequently, the experiments show that the API can significantly help library developers to achieve their goal.\n6.4 Conclusion\n\nIn this chapter, we have introduced the library development process by using the LDSpecX-based specification platform. A specification with 28nm FDSOI CMOS technology was defined for a standard cell library development. Even if these experiments dealt with only standard cell library, LDSpecX can cover other library categories by supplementing data for each library category. In the afore-described experiments, we saw how to rapidly develop a standard cell library from the LDSpecX-based specification with minimal human interventions in comparison with the traditional manual methods. As a consequence, the main contributions of the proposed prototype are not only to bridge the gap between the specification and the system, but also to improve the productivity of the library. In the next chapter, we conclude this thesis and give some perspectives for future work.\n7. **Conclusion and Perspectives**\n\nContents\n\n7.1 Conclusion ................................................................................................................. 98\n7.2 Perspectives ............................................................................................................. 101\n\n7.1 Conclusion\n\nIn this thesis, we presented a first attempt to deal with these inevitable problems relevant to the specification representing the cell-independent information because it becomes a significant bottleneck in library/IP development due to various factors; increasing needs of system designers, technology scaling, developing design methodology, and so on. Especially, the quantity of cell-independent information like PVT corners continuously increases with technology scaling. It can be a pressing problem for library/IP providers to produce their libraries with such information. Furthermore, the current specifications have some limitations such as informality and inconsistency to use their information. Thus, the formalism of the specification is firstly required because the well-formalized specification can enable end-users to explicitly identify the desired information and to manage it.\n\nBefore formalizing the specification, several existing specifications have been discussed with respect to the advantages of each form and the effectiveness of its data extraction method. Two well-known traditional specifications in natural language and tabular form were presented. Indeed, the current specifications of STMicroelectronics are also made up of these forms. However, these specifications are not an adapted form to allow to cover extending data because they require frequent modifications. For this reason, a novel approach is greatly required. Two rising methods based on UML and XML that are employed representing the system specification were introduced. The UML-based specification represents visual models by using various graphical notations. On the contrary, the XML-\nbased specifications like IP-XACT represents physical data model for modeling their information by using an XML language. However, they deal only with the description of systems or components until now so that it is difficult to apply them directly to our target information. Thus, we need a novel specification to address the issues of the current ones.\n\nIn order to clarify the issues to address in this thesis, three key points needed to be fully addressed. The first one relates to the formality and contents of the specification. The remaining two are related to the management of the specification from the perspectives of specification developer and library developer: specification creation and specification data extraction. These questions were addressed and the main contributions were oriented towards them:\n\n- **Unified specification for library development**\n\n We intended to propose an XML-based specification representing our target information. Thus, we conducted the analysis of data that are required by library development tools. That was the reason why it was necessary to identify all required data and to classify them for constructing a complete unified specification. An appropriate data model behind these observations was presented. By using this data model, a specification language based on XML named LDSpecX was proposed. This language allows encapsulating complete information for library development in a specification file.\n\n- **Efficient management of the specification**\n\n We introduced a reference-based method and task-based keywords to collaboratively and rapidly create reliable specifications as well as to precisely and rapidly obtain the specification data. Then, LDSpecX-based specification platform was built to implement the proposed methods for dealing with the specifications. This platform provides a user-friendly GUI and an API for creating specification and extracting data respectively. Figure 7.1 describes the developed specification platform. Additionally, a library verification tool based on the API was developed for verifying the library.\nFinally, we detailed the experiments to show the entire development process by using the developed prototype. An appropriate specification for standard cell library with 28nm FDSOI CMOS technology was first created using LDSpecX through the GUI. Then, we presented the development of a standard cell library including 11 combinational and sequential cells using this specification. This library package contains 86 library views to support all required design flows. These experiments show that the prototype significantly facilitates the entire library development process. As a result, we can reduce time and effort for library development. In addition, the proposed specification platform helps to remove potential errors by providing a unique reference database and facilities for dealing with specification data. Although only a standard cell library was dealt with experimentally, we can use our proposal for all library categories to support all required libraries and IPs for the design platform.\n7.2 Perspectives\n\nFirst, one of the imminent tasks to be done is the specification-driven automatic tool configuration. Even if we showed with a simple example, the automatic generation of tool input files by using the API, it is highly required to extend this automation because the library/IP developer often faces obstacles in adjusting the configuration of the system without the awareness of the tool configuration parameters. Specifically, since the tool often has more than one hundred parameters, it is very difficult for every end-user to perfectly take account of them in order to execute his tasks. The specification-driven automatic configuration may therefore ensure that the end-users are able to successfully attain their goals. Moreover it leads to efficiently improve the productivity of the library/IP.\n\nSecond, we need to allow the traceability of the specification. After producing the first version of the specification, it can usually be updated when receiving additional requests of customers, releasing a new version of tool, and so on. The changed information must be given in the new version of the specification. As a result of the update of the specification, the contents of all related libraries and IPs should be reproduced completely or partially depending on the impact of the changed information. In this case, generating only the impacted library views helps to save time and effort. We can obtain the information about the tasks to be executed in order to reproduce only the related views by reversely capturing the task information with the help of the task-based keywords. This future work would allow increasing the reusability of the existing library/IP package.\n\nThird, we also presented our prototype to design platform developers, library developers and in-house tool developers. They gave us some important feedbacks concerning this prototype in order to improve it. The most important one is to reuse the existing traditional specifications in natural language or tabular form. It can be very useful to create a specification reusing the existing one. However, we need an efficient method that allows capturing the information from these traditional documents to translate them into the LDSpecX-based specification.\n\nFinally, in this thesis, we focused on the specification for library/IP development. The proposed specification and its platform can further be extended for SoC design by covering the additional information such as library/IP package list that is only required to design a SoC. For this purpose, we need to add a new branch corresponding to the added data category in\nthe data structure of the specification without the modification of the existing one. The specification platform can be supported to the extended specification by enriching the reference and flow databases. This future work may greatly facilitate both library/IP developers as well as system designers to get the desired data from the specification.\nBibliography\n\n\nS. Chandrasekar and G. K. Varshney, \"A comprehensive methodology for noise\n\n\nPublications\n\n✓ INTERNATIONAL CONFERENCES\n\n\n✓ NATIONAL CONFERENCE\n\nRésumé\n\n1. Introduction\n\nGordon E. Moore a présenté la fameuse loi de Moore dans un article publié en 1965[1]. Cette loi prédit que le nombre de transistors des processeurs doublerait à coût constant tous les deux ans. De nos jours, une autre tendance nommée ‘More than Moore’ pour une diversification fonctionnelle, s’applique également. La figure 1.1 présente les diverses applications des systèmes sur puce (System-on-Chip SoC) vis-à-vis de ces différentes tendances.\n\nFigure 1.1 ‘Moore’s law’ et ‘More than Moore’ dans l’industrie des semi-conducteurs\n(source : ITRS)\n\nPour la conception de systèmes complexes, les fabricants de semi-conducteurs comme STMicroelectronics, fournissent à leurs clients une plateforme de conception (Design Platform DP) contenant tous les composants nécessaires comme des bibliothèques de cellules et des blocs plus complexes (Intellectual Property IP). Afin d’améliorer la productivité, en automatisant et sécurisant les processus de conception, de nouvelles approches sont\nnécessaires pour les concepteurs de systèmes et également pour les fournisseurs de bibliothèques.\n\nDans cette thèse, nous proposons d’améliorer le développement de bibliothèques par une meilleure formalisation des spécifications.\n\n2. Développement d’une bibliothèque de cellules et d’IPs à partir de la spécification de la plateforme de conception\n\nLa DP est une solution totale qui permet à une équipe de conception de produire un système sur puce. La spécification de DP doit définir une large gamme d’informations depuis les paramètres technologiques comme la nature du process, jusqu’aux conditions d’utilisation telles que la tension et la température, en passant par l’information sur les outils de conception (CAO) pour le développement de bibliothèques de cellules et d’IPs.\n\nLe développement d’une bibliothèque est effectué en quatre phases comme l’illustre la figure 2.1 : spécification, conception, dérivation et validation.\n\nFigure 2.1 Flot de développement de bibliothèques (source : ST)\nPour automatiser ce flot, STMicroelectronics a un système automatique qui est composé d’outils internes comme le montre la figure 2.2. Ces outils permettent d’exécuter des tâches de générer des vues nécessaires et de les vérifier avec des données extraites des spécifications.\n\nD’autre part, les développeurs de bibliothèques/IPs ont de plus en plus de difficultés à obtenir les données désirées à partir des spécifications existantes en raison de leur manque de formalisme et leur complexité. Nous avons d’abord identifié les problèmes concernant le contenu de la spécification et le traitement des spécifications par :\n\n- Spécification\n - Manque de formalisme\n - Inconsistance\n - Ambiguïté\n - Information manquante\n - Augmentation du volume de données\n\n- Création de la spécification\n - Manque d’une base de données de référence\n - Manque d’un outil assistant de la spécification\n - Manque de vérification de la spécification\nExtraction des données de spécification\n\n- Nécessité de méthodes efficaces et d’un outil pour l’extraction des données de spécification\n\n3. Etat de l’art\n\nLa spécification représente une collection d’informations pour effectuer une activité. Plusieurs formes peuvent être utilisées pour définir cette spécification. Traditionnellement, les spécifications sont écrites en langage naturel ou sous forme de tableaux. La méthode basée sur le langage naturel est une méthode très courante pour définir l’information mais pour avoir une forme non-ambiguë, il faut utiliser des phrases très simples et un vocabulaire limité. D’ailleurs, pour effectuer l’extraction de l’information à partir de ce type de spécification, il faut une bonne analyse sémantique [84], [85]. Par contre, la méthode basée sur des tableaux permet de facilement étendre l’information et de rapidement l’extraire en identifiant les colonnes et les lignes ou en utilisant des modèles. Cependant, ce type de spécification a également quelques limitations comme l’indépendance des données [87], [88], [89], [90], [91]. Récemment, deux spécifications basées sur le langage de modélisation unifié (Unified Modeling Language UML) et le langage de balisage extensible (eXtensible Markup Language XML) ont aussi été utilisées dans le domaine du système. L’UML basé sur les notations graphiques fournit beaucoup d’expressions pour décrire la spécification d’un système mais il représente un modèle conceptuel [94], [95]. L’XML permet d’enregistrer de nombreux types de données en forme textuelle avec des balises. Donc, il est largement appliqué à divers domaines grâce à ses nombreux avantages comme l’extensibilité, la portabilité et la lisibilité par une machine. Par exemple, IP-XACT [98] et ASDeX [106] sont proposés pour représenter la spécification d’IPs numériques et celle d’IP analogique respectivement à l’aide de XML. Malheureusement, ces spécifications existantes ne peuvent représenter l’ensemble de nos informations. Enfin, les spécifications actuelles de STMicroelectronics font appel au langage naturel et aux tableaux selon les caractéristiques des données comme le montre la figure 3.1.\nFigure 3.1 Extrait des spécifications de plateforme de conception (source: ST)\n\nEn résumé, les avantages et les inconvénients de tous les types de spécifications sont donnés dans le tableau 3.1 du point de vue de la modélisation des données et du traitement de ces données. Dans ce tableau, un cercle vert indique que le type de spécification est adapté au critère au contraire d’une croix rouge. D’après ce tableau, les spécifications de STMicroelectronics basées sur le langage naturel et des tableaux, ont des avantages comme l’extensibilité et la flexibilité pour la modélisation des données, ainsi que la facilité pour les entrer et la lisibilité humaine pour les traiter. En revanche, elles ont des inconvénients comme la manque de formalisme pour la modélisation et la difficulté d’extraire des données pour leur traitement. C’est pourquoi nous proposons une spécification basée sur XML pour le développement de bibliothèques car XML fournit le plus d’avantages pour encapsuler une large gamme d’informations et facilement traiter des données.\nTable 3.1: Résumé des spécifications\n\n<table>\n<thead>\n<tr>\n<th>Critères</th>\n<th>Spécification basée sur le langage naturel</th>\n<th>Spécification basée sur les tableaux</th>\n<th>Spécification basée sur l’UML</th>\n<th>Spécification basée sur l’XML</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Formalisme</td>\n<td>✗</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Extensibilité</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Flexibilité</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Expressivité</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Disponibilité de divers types de données</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Relation entre les données</td>\n<td>✗</td>\n<td>✗</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Traitement des données</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Facilité d’entrer des données</td>\n<td></td>\n<td></td>\n<td>✗</td>\n<td></td>\n</tr>\n<tr>\n<td>Facilité d’extraire des données</td>\n<td>✗</td>\n<td></td>\n<td>✗</td>\n<td></td>\n</tr>\n<tr>\n<td>Lisibilité humaine</td>\n<td></td>\n<td></td>\n<td></td>\n<td>✗</td>\n</tr>\n<tr>\n<td>Lisibilité par machine</td>\n<td>✗</td>\n<td>✗</td>\n<td>✗</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n4. Méthodologies pour la spécification du développement de bibliothèques\n\nNous proposons un formalisme de la spécification pour le développement de bibliothèques. De plus, nous présentons deux méthodes pour la création de la spécification et l’extraction des données.\n\n- **Formalisme de spécification**\n\n Pour formaliser les spécifications pour le développement de bibliothèques, il faut d’abord établir un modèle de données approprié. C’est pour cette raison que nous avons identifié et classifié toutes les données utilisées par les outils internes pour le développement\nd’une bibliothèque. La figure 4.1 représente les résultats d’analyse des données d’entrée des outils. D’après ces résultats, toutes les données identifiées peuvent être classifiées en trois groupes : paramètres d’outil, paramètres de vue et paramètres de technologie.\n\nEn conséquence, nous avons proposé une taxonomie des données de la spécification comme le montre la figure 4.2. Cette taxonomie est une fondation du modèle de données.\n\nFigure 4.2 Taxonomie des données de la spécification\nA l’aide de cette taxonomie, nous avons établi un modèle de donnée approprié. Ce modèle nous permet de représenter toutes les informations nécessaires pour le développement de bibliothèques. La figure 4.6 donne tous les objets modélisant les données et leurs relations.\n\n\n\n**Figure 4.3** Données de la spécification et leurs relations\n\nL’objet modélisant la donnée représente un ensemble de paramètres explicité dans la figure 4.4 en utilisant un diagramme de classe UML. L’information sur un paramètre est donnée par un nom et au moins une valeur. Ce modèle de donnée basique est utilisé pour construire le modèle de donnée pour la spécification.\n\n\n\n**Figure 4.4** Objet de donnée\n\nIl y a deux sortes d’ensembles de paramètres selon qu’ils soient sous-catégorisés ou non. La figure 4.5 donne un exemple de ces deux sortes d’ensembles de paramètres. Le\npremier est un ensemble de paramètres généraux de technologie. Le deuxième représente un sous-ensemble de paramètres spécifiques de technologie en fonction de la catégorie de bibliothèque.\n\nD’autre part, pour définir un paramètre, nous proposons une méthode simple et unifiée pour donner un nom et des valeurs. Il y a aussi deux sortes de paramètre selon qu’il a un attribut clé ou non. Cet attribut est utilisé chez STMicroelectronics pour identifier un paramètre au lieu du nom. La figure 4.6 donne des exemples de ces deux sortes de paramètres. Le premier permet de donner un nom et au moins une valeur pour définir un paramètre général de technologie. Le deuxième permet de donner un nom, une version comme valeur et un attribut clé pour définir l’information d’un outil.\nMéthode basée sur les références pour la création de la spécification\n\nL’objectif de cette méthode est de créer une spécification consistante et complète en fournissant autant d’informations prédéfinies que possible à partir d’une base de données de références centralisée. Nous proposons deux modèles pour ces références : le dictionnaire et la liste.\n\nPremièrement, le dictionnaire contient une collection de termes contenant un nom et des valeurs comme le montre dans la figure 4.7. Cette référence couvre le premier type de paramètre en offrant la liste de paramètres et des valeurs possibles du paramètre.\n\nDeuxièmement, la liste vise à fournir une liste complète des paramètres avec leurs attributs clés pour aider à définir le deuxième type de paramètres comme le montre dans la figure 4.8.\n\nLa figure 4.9 illustre le flot de création des spécifications basées sur ces deux types de références. Le premier flot à droite consiste à obtenir une liste de paramètres et leurs valeurs possibles par recherche à partir du dictionnaire. Le deuxième flot à gauche consiste à obtenir une liste complète de paramètres avec leur information d’identification à partir de la liste et d’entrer la valeur du paramètre par le développeur de spécification. A la fin, toutes les données obtenues sont définies dans une spécification.\nMots-clés basés sur les tâches pour l'extraction de données\n\nLe développeur de bibliothèque doit exécuter des tâches pour développer une bibliothèque. Une des difficultés les plus importantes est d’obtenir des données de la spécification pour effectuer chaque tâche. Pour l’extraction de données à partir de la spécification proposée, nous proposons d’abord d’utiliser des mots-clés. Ils peuvent se représenter par un ensemble de quatre éléments : paramètre, catégorie, nom ou clé, et identificateur (id).\n\n\\[ \\text{Mot} - \\text{Clé} = (\\text{Paramètre}, \\text{Catégorie}, \\text{Nom ou Clé, Id}) \\]\n\nCet ensemble d’éléments permet d’identifier un paramètre ou un ensemble de paramètres de la spécification selon les besoins de l’utilisateur. De plus, pour extraire les données nécessaires pour une tâche à accomplir, nous proposons de définir la relation entre les tâches et les données de la spécification en utilisant ces mots-clés. L’ensemble des mots-clés pour une tâche peut être exprimé par :\n\n\\[ \\text{Mots} - \\text{Clés}_{\\text{Tâche}} = \\bigcup_{i=1}^{m} \\text{Mot} - \\text{Clé}_i \\]\n\n\\[ = \\bigcup_{i=1}^{m} (\\text{Paramètre}_i, \\text{Catégorie}_i, \\text{Nom}_i \\text{ ou } \\text{Clé}_i, \\text{Id}_i) \\]\n5. Implémentation : Plateforme de spécification\n\nEn utilisant le modèle de données présenté précédemment, nous avons développé un langage de spécification basé sur XML nommé LDSpecX [108] ainsi que la plateforme de spécification. Cette plateforme vise non seulement à créer une spécification consistante et complète avec une grande quantité de données mais également à rapidement et précisément extraire ces données selon la tâche à accomplir.\n\n- Spécification basée sur XML pour le développement de bibliothèque (LDSpecX)\n\nLe langage de spécification LDSpecX est développé en proposant un schéma XML qui représente sa syntaxe. Ce schéma est montré dans la figure 5.1. En utilisant ce langage, nous pouvons définir toutes les données nécessaires pour le développement de bibliothèques.\n\n\n\n- Création de la spécification\n\nNous avons proposé une base de données de références auparavant. Cette base de données est construite en créant un dictionnaire et deux listes de référence pour les outils et les vues. A l’aide de cette base de données, nous avons développé un outil pour la création de la spécification [115]. En utilisant cet outil, une spécification en LDSpecX peut être créée en suivant le flot donné dans la figure 5.2. D’abord, la spécification est divisée en plusieurs\nmorceaux nommés fragments pour que les données d’une même catégorie soient collectées indépendamment. Le flot est divisé en deux étapes. La première étape est de créer un fragment de la spécification et de vérifier qu’il contient tous les paramètres. Cette étape doit être répétée jusqu’à ce que tous les fragments soient créés. Après la création des fragments, nous pouvons passer à la deuxième étape consistant à les combiner afin de produire une spécification finale. À la fin de cette étape, nous vérifions que le résultat est complet, consistant et correct. De plus, la syntaxe de la spécification est également vérifiée.\n\nFigure 5.2 Flot de création de spécification basée sur les références\n\nNous avons développé une interface graphique (Graphic User Interface GUI) en Python qui permet d’accéder à la base de données de références pour obtenir les informations prédéfinies. La figure 5.3 montre la page de saisie des données pour créer un fragment sur des paramètres généraux de technologie à l’aide du dictionnaire. Premièrement, une liste de paramètres est obtenue à partir du dictionnaire pour la faire apparaître sur la page de saisie des\nDonnées. Deuxièmement, les valeurs de paramètres doivent être définies soit en les obtenant directement à partir du dictionnaire, soit en les entrant manuellement.\n\nFigure 5.3 Page de saisie des données pour des paramètres généraux de technologie\n\nLa figure 5.4 montre la page de saisie des données pour définir l’information liée aux outils à l’aide d’une liste de référence pour les outils. Ceci fournit une liste complète des outils nécessaires avec leur clé et nom. C’est pour cela que le développeur de spécification peut facilement définir toute l’information liée aux outils.\nFigure 5.4 Page de saisie de données pour l’information des outils\n\nLa figure 5.5 montre la page de création de la spécification en LDSpecX. Tous les fragments obtenus à partir des étapes précédentes doivent être combinés pour générer une spécification en LDSpecX.\n\nComme décrit précédemment, cette plateforme fournit aux développeurs de spécification une base de données unique de références ainsi qu’un flot unifié. En conséquence, elle peut aider à créer une spécification complète et consystante.\nExtraction des données de la spécification\n\nNous avons développé une interface de programmation d’applications (Application Programming Interface API) en Perl basée sur la méthode d’extraction de données vue précédemment. D’abord, nous devons définir la relation entre les tâches et les données de spécification en utilisant des mots-clés. Cependant, les données de spécification nécessaires dépendent de la catégorie de bibliothèque. Pour cette raison, il faut définir les tâches pour le développement de bibliothèques pour chaque catégorie de bibliothèque séparément comme le montre dans la figure 5.6 (a). Chaque tâche peut avoir plus d’un sélecteur qui contient un mot-clé pour faire le lien avec les paramètres de spécification comme l’illustre la figure 5.6 (b). En utilisant ce schéma, des mots-clés pour toutes les tâches du flot de développement de bibliothèques ont été prédéfinis et stockés dans un fichier XML.\nAprès la création du flot, nous avons développé une API qui permet d’accéder à la base de données de LDSpecX comme l’illustre la figure 5.7.\n\nFigure 5.7 API\nCette API fournit aux utilisateurs des fonctions pour extraire des données. Les deux fonctions fondamentales sont :\n\n1) **getSpecData** (spécification, mot-clé): renvoie les données obtenues à partir de la spécification basée sur LDSpecX (fichier XML) utilisant un mot-clé donné (chaîne de caractères).\n\n2) **getFlowInfo** (catégorie de bibliothèque, tâche): renvoie les mots-clés à partir du flot de développement de bibliothèques (fichier XML) selon la catégorie de bibliothèque et la tâche (chaînes de caractères).\n\nDe plus, en utilisant ces fonctions, une fonction permettant d’extraire des données selon la tâche désirée est également fournie :\n\n3) **getSpecDataViaFlow** (spécification, catégorie de bibliothèque, tâche): renvoie toutes les données nécessaires à partir de la spécification basée sur LDSpecX (fichier XML) pour une tâche désirée (chaîne de caractères).\n\nLa figure 5.8 montre un flot pour l’extraction de données en utilisant des mots-clés basés sur les tâches. Premièrement, les mots-clés sont collectés à partir du fichier de flot. Deuxièmement, en utilisant ces mots-clés, les données peuvent être obtenues à partir de la base de données de spécifications.\n\n\n\nFigure 5.8 Extraction de données en utilisant des mots-clés basés sur les tâches\nEn utilisant les fonctions de l’API, nous avons développé des outils pour extraire des données automatiquement et un outil de vérification de la bibliothèque par rapport à la spécification.\n\n6. Expérimentation\n\nExpérimentalement, nous avons effectué le développement d’une bibliothèque de cellules standard (portes logiques) à partir de la création d’une spécification jusqu’à la validation de la bibliothèque en utilisant la plateforme de spécification présenté précédemment.\n\nPremièrement, nous avons créé, à l’aide du GUI, une spécification en technologie 28nm CMOS FDSOI pour la bibliothèque de cellules standard avec une réduction considérable du temps de développement. Le tableau 6.1 donne un comparatif de la de spécification basée sur LDSpecX avec les spécifications traditionnelles.\n\n<table>\n<thead>\n<tr>\n<th>Catégorie d’information</th>\n<th>Paramètre</th>\n<th>Nombre de paramètres</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td>Spécifications</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>traditionnelles</td>\n</tr>\n<tr>\n<td>Technologie</td>\n<td>Paramètre général de technologie</td>\n<td>6</td>\n</tr>\n<tr>\n<td></td>\n<td>Paramètre spécifique de technologie</td>\n<td>6</td>\n</tr>\n<tr>\n<td></td>\n<td>PVT</td>\n<td>20</td>\n</tr>\n<tr>\n<td></td>\n<td>Paramètres de caractérisation</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Référence de caractérisation</td>\n<td>-</td>\n</tr>\n<tr>\n<td></td>\n<td>Pente</td>\n<td>240</td>\n</tr>\n<tr>\n<td></td>\n<td>Charge capacitive</td>\n<td>1136</td>\n</tr>\n<tr>\n<td>Outils</td>\n<td>Outil</td>\n<td>73</td>\n</tr>\n<tr>\n<td></td>\n<td>Paramètre de configuration de l’outil</td>\n<td>-</td>\n</tr>\n<tr>\n<td>Vues</td>\n<td>Vue</td>\n<td>154</td>\n</tr>\n<tr>\n<td></td>\n<td>Attribut de la vue</td>\n<td>10</td>\n</tr>\n<tr>\n<td>Flots de conception</td>\n<td>Flot de conception du SoC</td>\n<td>3</td>\n</tr>\n</tbody>\n</table>\nDeuxièmement, à partir de cette spécification, nous avons développé une bibliothèque contenant 11 cellules combinatoires et séquentielles. Les tâches nécessaires ont été exécutées en utilisant les outils internes et l’API. Cette API permet d’extraire les données nécessaires beaucoup plus rapidement qu’avec la méthode traditionnelle (semi-manuelle). En conséquence, 86 vues ont été produites. Finalement, la bibliothèque obtenue a été vérifiée par l’outil de vérification développé à l’aide de l’API.\n\nEnfin, cette plateforme aide à réduire le gap entre la spécification et le système automatique actuel pour le développement rapide de bibliothèques.\n\n7. Conclusion et perspectives\n\nDans cette thèse, nous avons proposé des méthodologies, des flots et des outils pour formaliser les spécifications pour le développement de bibliothèques et la traiter efficacement. Cette spécification vise à être utilisée comme une référence pour générer et valider des bibliothèques (e.g. cellules standard, cellules d’entrée/sortie, mémoires, etc.) ainsi que des IPs complexes (PLL, etc.)\n\nNous avons proposé une spécification unifié basée sur XML nommée LDSpecX. Ce langage de spécification permet d’encapsuler toutes les informations nécessaires pour le développement de bibliothèques de cellules et d’IPs. En utilisant LDSpecX, nous avons également développé une plateforme de spécification. Cette plateforme nous permet de créer une spécification consistante et complète en LDSpecX par un flot unifié et de précisément et rapidement extraire les données nécessaires à partir de la spécification selon une tâche désirée à l’aide des GUI et API respectivement. La figure 7.1 illustre la vue d’ensemble de la plateforme de spécification.\nFigure 7.1 Plateforme de spécification\n\nUne principale perspective de recherche qui apparaît à l’issue de cette thèse concerne l’extension à la configuration automatique des outils pour couvrir le développement de toutes les catégories de bibliothèques en plus des bibliothèques de cellules standard. En outre, la traçabilité de la spécification serait efficace pour donner l’information détaillée sur le changement des données. En utilisant les mots-clés basés sur les tâches qui définissent la relation entre les tâches et les données de la spécification, nous pouvons facilement reconnaître des tâches liées au changement de données. Cela permettrait d’effectuer uniquement les tâches concernées pour produire une bibliothèque avec une nouvelle version de la spécification. Par conséquence, ces perspectives de recherches pourraient considérablement aider à améliorer la productivité du développement de bibliothèques. De plus, la transformation des spécifications traditionnelles existantes en spécification basée sur LDSpecX serait nécessaire du point de vue du développeur de spécification pour les réutiliser. La spécification proposée et sa plateforme peuvent aussi être étendues pour la conception de systèmes en couvrant les informations additionnelles comme, par exemple, la liste de bibliothèques et d’IPs. Ce travail futur peut faciliter les développeurs de bibliothèque/IP ainsi que les concepteurs de systèmes pour obtenir les données nécessaires à partir de la spécification."}}},{"rowIdx":58,"cells":{"id":{"kind":"string","value":"6cb6e453641b77374df907759d99a81ef33a1dd7"},"text":{"kind":"string","value":"Maintaining Consistency between a Design Model and Its Implementation\n\nHector M. Chavez\nWestern Michigan University, hmch.chavez@gmail.com\n\nFollow this and additional works at: https://scholarworks.wmich.edu/dissertations\n\nPart of the Computer Sciences Commons\n\nRecommended Citation\nhttps://scholarworks.wmich.edu/dissertations/735\n\nThis Dissertation-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Dissertations by an authorized administrator of ScholarWorks at WMU. For more information, please contact maira.bundza@wmich.edu.\nMAINTAINING CONSISTENCY BETWEEN A DESIGN MODEL AND ITS IMPLEMENTATION\n\nby\n\nHector M. Chavez\n\nA dissertation submitted to the Graduate College in partial fulfillment of the requirements for the degree of Doctor of Philosophy\nComputer Science\nWestern Michigan University\nAugust 2015\n\nDoctoral Committee:\nLaura K. Dillon, Ph. D.\nRobert B. France, Ph. D.\nAjay Gupta, Ph. D.\nWuwei Shen, Ph. D., Chair\nLi Yang, Ph. D.\nMAINTAINING CONSISTENCY BETWEEN A DESIGN MODEL AND ITS IMPLEMENTATION\n\nHector M. Chavez, Ph.D.\nWestern Michigan University, 2015\n\nSoftware design models are increasingly being used as part of the software development process as analysis and design artifacts and to automatically generate code that developers can further modify or extend, greatly expediting the software development process. This, however, has introduced the challenge of maintaining consistency between the design models and their implementation as they evolve during the development process. Traditional software testing and verification techniques have been well studied in the past, and they are an integral part of many software development projects, however, they are not well suited for consistency checking between a design model and its implementation. In this dissertation, we present a testing-based validation technique that improves over traditional testing and verification techniques for consistency checking that combines coverage criteria and dynamic symbolic execution with path condition analysis. Our experiments have shown the effectiveness and efficiency of our approach when applied to industry strength software systems.\nI first would like to thank my advisor Wuwei Shen for all his help during my years as a graduate student. His guidance and support has been an integral part on the development of my research work, and being where I’m would not have been possible without his constant encouragement. I’m greatly in debt for all that he taught me and for introducing me to the ideas that ultimately lead to this thesis.\n\nI want to thank the members of my doctoral committee for their input when working on my thesis and research. To all my professors at WMU from whom I have learned a great deal during my graduate studies. And to colleges and members of our research group who collaborated with me, specially Benjamin Mechling who worked with me in the implementation of CCUJ’s dynamic symbolic execution.\n\nOutside from our research group, I would like to thank the developers in the modeling community who where kind enough to answers many of my questions when working in the project. To Kenn Hussey from the Eclipse Community Forums, for his suggestions and help confirming some of the bugs and findings in my research.\n\nFinally, I would like to thank my family and friends for all their support and encouragement. My parents Miguel and Socorro for their unconditional support and love. My brothers Abel and Jose, and sisters, Marivel and Alicia, for always being there when I need them. And lastly, to my uncle and aunt Andy and Alicia Blodgett, for all their support and for allowing me to be part of their family during my stay in Michigan.\n\nHector M. Chavez\n# TABLE OF CONTENTS\n\n## ACKNOWLEDGEMENTS\n\n## LIST OF TABLES\n\n## LIST OF FIGURES\n\n## CHAPTER\n\n### I. INTRODUCTION\n\n1.1 Organization\n\n### II. BACKGROUND AND RELATED WORK\n\n2.1 Unified Modeling Language\n 2.1.1 Class Diagrams\n\n2.2 Object Constraint Language\n 2.2.1 Initial Values\n 2.2.2 Query Operations\n 2.2.3 Attributes and Operations Definition\n 2.2.4 Invariants\n 2.2.5 Preconditions and Postcondition\n\n2.3 Model Driven Architecture\n 2.3.1 Terminology\n 2.3.2 MDA Process\n 2.3.3 UML to Java\n\n2.4 Symbolic and Dynamic Symbolic Execution\n 2.4.1 Symbolic Execution\n 2.4.2 Dynamic Symbolic Execution\n\n2.5 Software Verification\n\n2.6 Program Testing\n\n2.7 Model Based Testing\n\n### III. BOUNDED EXHAUSTIVE TESTING\nCHAPTER\n\n3.1 Overview .............................................. 34\n 3.1.1 Input ........................................... 34\n 3.1.2 General Steps .................................. 34\n 3.1.3 Formalization of UML Associations ............. 35\n 3.1.4 Our Approach .................................. 41\n 3.1.5 Small Scope Hypothesis ......................... 52\n3.2 Bounded Exhaustive Testing Limitations ............. 53\n 3.2.1 Effectiveness .................................. 53\n 3.2.2 Efficiency .................................... 54\n\nIV. PATH CONDITION ANALYSIS .......................... 56\n 4.1 Overview .......................................... 56\n 4.2 Algorithm ....................................... 63\n 4.2.1 Initialization ................................ 63\n 4.2.2 Test Case Generation .......................... 65\n 4.2.3 Methods Execution and Evaluation .......... 67\n 4.2.4 Multiplicity and Navigability as OCL Pre-Conditions 71\n 4.2.5 Black Box Methods ............................ 72\n\nV. EVALUATIONS ........................................... 83\n 5.1 Bounded Exhaustive Testing ....................... 83\n 5.1.1 Effectiveness ................................ 84\n 5.1.2 Efficiency .................................. 85\n 5.2 Mutation Testing .................................. 87\n 5.3 Path Condition Analysis ......................... 89\n 5.3.1 Effectiveness ................................ 89\n 5.3.2 Efficiency .................................. 91\n\nVI. CONCLUSIONS ......................................... 99\n\nAPPENDICES ................................................ 101\n A.1 Navigability ...................................... 102\n A.1.1 Navigability Constraint at M2 Level .......... 103\n A.1.2 Algorithm to Generate Navigability Constraint at M1 Level ................. 104\n A.1.3 Navigability Constraint at M1 Level .......... 104\n A.2 Multiplicity ...................................... 105\n A.2.1 Multiplicity Constraint at M2 Level .......... 106\nAPPENDICES\n\nA.2.2 Algorithm to Generate Multiplicity Constraint at M1 Level ......................................... 106\nA.2.3 Multiplicity Constraint at M1 Level ................................................................. 107\nA.3 Subsetting ........................................................................................................... 107\n A.3.1 Subsetting Constraint at M2 Level .............................................................. 108\n A.3.2 Algorithm to Generate Subsetting Constraint at M1 Level ............................. 108\n A.3.3 Subsetting Constraint at M1 Level .............................................................. 109\nA.4 Union .................................................................................................................. 109\n A.4.1 Union Constraint ......................................................................................... 109\n A.4.2 Algorithm to Generate Union Constraint at M1 Level ................................. 110\n A.4.3 Union Constraint at M1 Level ..................................................................... 110\nA.5 Redefinition ......................................................................................................... 111\n A.5.1 Redefinition Constraint ............................................................................. 111\n A.5.2 Algorithm to Generate Redefinition Constraint at M1 Level .......................... 111\n A.5.3 Redefinition Constraint at M1 Level ............................................................ 112\nA.6 Composition ......................................................................................................... 112\n A.6.1 Composition Constraints ............................................................................ 114\n A.6.2 Algorithm to Generate Composition Constraint at M1 Level ....................... 114\n A.6.3 Composition Constraint at M1 Level ........................................................... 115\nA.7 Composition Constraint Auxiliary Operations ......................................................... 116\n A.7.1 isComposition() ....................................................................................... 116\n A.7.2 isCompositeClass() .................................................................................... 116\n A.7.3 superClasses() ............................................................................................ 116\n A.7.4 ownedClasses() ......................................................................................... 117\n A.7.5 isOwnedClass() .......................................................................................... 117\n A.7.6 compositions() ......................................................................................... 117\n A.7.7 instances() .................................................................................................. 117\n A.7.8 isUndefined() ............................................................................................. 118\n A.7.9 ownerCompositions() .................................................................................. 118\n A.7.10 ownsObject(i:InstanceSpecification) ......................................................... 118\n A.7.11 linkExist(a1:Association, a2:Association) .................................................. 118\n\nBIBLIOGRAPHY ........................................................................................................ 137\nLIST OF TABLES\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>Title</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2.1</td>\n<td>RSA transformation rules.</td>\n<td>18</td>\n</tr>\n<tr>\n<td>2.2</td>\n<td>Symbolic execution example.</td>\n<td>22</td>\n</tr>\n<tr>\n<td>2.3</td>\n<td>Dynamic symbolic execution example.</td>\n<td>23</td>\n</tr>\n<tr>\n<td>3.1</td>\n<td>Test input space (2,2,1) for the class diagram in Figure 3.12.</td>\n<td>47</td>\n</tr>\n<tr>\n<td>5.1</td>\n<td>Forward engineering tools test.</td>\n<td>85</td>\n</tr>\n<tr>\n<td>5.2</td>\n<td>Comparison with <em>Korat.</em></td>\n<td>94</td>\n</tr>\n<tr>\n<td>5.3</td>\n<td>Test case generation comparison.</td>\n<td>94</td>\n</tr>\n<tr>\n<td>5.4</td>\n<td>Mutations for method <code>getOpposite()</code></td>\n<td>95</td>\n</tr>\n<tr>\n<td>5.5</td>\n<td>Mutations for method <code>earn()</code></td>\n<td>96</td>\n</tr>\n<tr>\n<td>5.6</td>\n<td>Mutation testing comparison.</td>\n<td>97</td>\n</tr>\n<tr>\n<td>5.7</td>\n<td>Test case generation comparison.</td>\n<td>98</td>\n</tr>\n</tbody>\n</table>\nLIST OF FIGURES\n\n2.1 UML class with two attributes and one operation. ........................................ 7\n2.2 Inheritance relationship. ................................................................. 8\n2.3 Class diagram with bi-directional association........................................ 9\n2.4 Class diagram with uni-directional association..................................... 10\n2.5 Flights class diagram without OCL. ................................................... 11\n2.6 MDA pattern. ................................................................................. 16\n2.7 Model marking. ............................................................................... 17\n2.8 Class diagram (PSM) to Java program (Code). .................................... 18\n2.9 Source class diagram (PIM). ............................................................ 18\n2.10 Code generated for classes and properties. ......................................... 19\n2.11 Code generated for associations. ...................................................... 20\n2.12 Code generated for operations. ......................................................... 20\n2.13 Example method for symbolic execution. ........................................... 22\n2.14 Sample code for traditional testing. .................................................. 26\n2.15 Two composition implementations. ................................................... 29\n2.16 UML meta-model fragment. ............................................................. 29\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Title</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>5.4</td>\n<td>OCL post condition and generated Java Boolean method.</td>\n<td>91</td>\n</tr>\n<tr>\n<td>A.1</td>\n<td>Navigability on a class diagram.</td>\n<td>103</td>\n</tr>\n<tr>\n<td>A.2</td>\n<td>An object diagram for class diagram in Figure 7.1(a)</td>\n<td>103</td>\n</tr>\n<tr>\n<td>A.3</td>\n<td>Qualified association.</td>\n<td>105</td>\n</tr>\n<tr>\n<td>A.4</td>\n<td>Class diagram with multiplicity constraints.</td>\n<td>106</td>\n</tr>\n<tr>\n<td>A.5</td>\n<td>Subsetting and Union associations.</td>\n<td>108</td>\n</tr>\n<tr>\n<td>A.6</td>\n<td>Composition example.</td>\n<td>115</td>\n</tr>\n<tr>\n<td>A.7</td>\n<td>Shared composition example.</td>\n<td>116</td>\n</tr>\n</tbody>\n</table>\nCHAPTER I\n\nINTRODUCTION\n\nIn the past three decades, we have become increasingly dependent on computer applications. From simple embedded applications in domestic appliances to medical hardware and information systems, computer applications have penetrated into every aspect of life, making possible most of the activities that are an integral part of modern societies. This wide adoption of computer applications has made software correctness one of the primary goals in the software development process.\n\nUnfortunately, ensuring software correctness has become increasingly challenging as the size and complexity of software applications increases. As an example, the first release of the Linux operating system kernel in 1991 consisted of about 10,000 source lines of code (SLOC), and twelve years later, the kernel version 2.6.0 included over 5 million SLOC [1]. Also, the introduction of hardware improvements has made software development harder. For example, the use of multi-core systems has introduced non-deterministic behavior that makes it harder to implement correct reliable software.\n\nAs our reliance on software applications increases, the impact of software errors, or software problems that affect a computer application, has serious consequences in our daily life. A study conducted by the National Institute of Standards and Technology in 2002 estimates that software errors cost about $59 billion every year. This includes\nresources used by the user to mitigate the undesired effects and the cost for developers to fix the problems [2]. Other errors could have more devastating effects, such as life losses caused by failures in medical equipment [3] or transportation systems.\n\nNumerous techniques have been used to improve the quality and reduce the likelihood or number of errors in computer applications, as well as speed up the development process. These techniques are normally seen as part of the software engineering discipline, an engineering discipline which applies systematic approaches to various phases during the software development process such as design, implementation, testing and maintenance phases [4].\n\nWith the increasing size and complexity of a problem domain, it becomes harder to understand, design, and maintain a software system. This creates a gap between the problem domain, which has become more complex as available hardware improves, and the solution domain. One way of tackling the complexity problem is by using a stepwise refinement approach, where at each step a new level of abstraction is introduced, going from the more general, e.g., a high level design, to the more detailed, e.g., a program implementation. It is in this area where Model Driven Architecture (MDA) [6] plays an important role by trying to link the artifacts produced at different levels of abstraction. One way MDA tries to achieve this goal is with the use of forward engineering tools, where an artifact, such as a class diagram, can be used to automatically generate a more detailed artifact, e.g., a Java program, greatly expediting the development process.\n\nHowever, most forward engineering tools only generate skeletal programs and it is the developer’s responsibility to manually implement the features not supported by the forward engineering tool. This can lead to inconsistencies introduced by the developers when extending the generated skeletal program that may cause undesired behavior on a system. As a result, it is a challenging issue to determine if the developer’s implementation satisfies the constraints specified in the model. Specifically, at\nthe core of the Model Driven Architecture, the Unified Modeling Language (UML) [7], a general purpose modeling language, is used to describe a system’s structure, behavior, and architecture. And the Object Constraint Language (OCL) [8] has been proposed as a complementary specification language that can be used to define constraints over the elements in a design model.\n\nExisting approaches have studied the problem of consistency checking between different types of models but none of them have considered consistency checking between a design model and its implementation [34, 35, 36, 37]. Also, reverse engineering techniques have been applied to check specific UML class diagram properties, such as association properties, however, their approaches are limited at recovering properties that can be statically inferred, they don’t recover features that require a program execution, such as the UML composition property. Also related to consistency checking, some existing approaches consider the generation of test cases from behavioral models [22, 23, 24, 25, 26, 27, 28, 29] such as activity or sequence diagrams, but do not consider class diagrams or method constraints.\n\nTo tackle the issue of consistency checking between a design model and its implementation, we introduce a bounded exhaustive testing technique with a pruning approach that analyses the fields accessed during the execution of the method under test. This technique is based on the small scope hypothesis and it can efficiently generate a small number of test cases. However, it cannot guaranty the correctness of the program. To overcome this limitation, we also introduce an approach to consistency checking between a model, i.e., class diagram, and its Java implementation, in terms of the OCL constraints specified in the model as method post conditions. In this approach, we automatically generate a Java Boolean post method from a method post condition and determine whether the method always returns true right after the execution of the method under test. We follow a testing-based validation technique that combines coverage criteria and dynamic symbolic execution.\nUnlike traditional testing, our approach considers the relationship of the path conditions of the method under test and its post method when generating test cases, and thus that allows us to guarantee the correctness of the method under test in terms of its OCL post condition. On the other hand, traditional program testing techniques only rely on different coverage criteria, e.g., branch coverage, to generate test cases and assume that the execution of a faulty statement can expose a software fault, which is not always the case. Also, traditional testing techniques modify the values of the fields that appear in branch conditions in order to explore different execution paths in the program. This can be problematic for consistency checking in the context of Model Driven Architecture, since the automatically generated code often includes auxiliary fields with values that correspond to specific features in the model. Modifying auxiliary fields to cover a different execution path could result in a false positive due to the underlying program structure no longer matching the original model. Moreover, traditional testing techniques cannot handle cases with black box methods, i.e., methods that cannot be symbolically executed. To handle this scenarios, we introduce an approximate symbolic execution technique, an extension over traditional program testing.\n\nThe main contributions of this dissertation are the following:\n\n• We introduce a bounded exhaustive testing technique to check the consistency between UML association properties in a class diagram and their implementation.\n\n• We introduce a model based testing approach that determines whether OCL constraints in a UML class diagram are violated in a Java implementation.\n\n• We introduce a new pruning technique, that analyses the path conditions of the method under test and its post condition method.\n\n• We introduce an approximate symbolic execution technique, an improvement\nover traditional testing, that can handle the execution of black box methods.\n\n- We present an approach to automatically generate a set of high-quality test cases to efficiently explore different execution paths of the implementation.\n\n- We applied our approach to two EMF UML2 industry-strength projects.\n\n1.1 Organization\n\nThe remainder of this dissertation is organized as follows. Chapter II introduces background topics related to consistency checking and related work, such as model driven architecture, and dynamic symbolic execution. Chapter III presents our approach to consistency checking with bounded exhaustive testing. Chapter IV introduces our approach to consistency checking with path condition analysis, which improves over bounded exhaustive testing. Chapter V discusses the evaluation of both approaches and shows experimental results. Chapter VI concludes.\nCHAPTER II\n\nBACKGROUND AND RELATED WORK\n\n2.1 Unified Modeling Language\n\nThe Unified Modeling Language is a general purpose modeling language which can be used to describe a system from different aspects, such as structural, behavioral, and architecture. The Unified Modeling Language is composed by different types of diagrams, such as class diagrams, used to model the static structure of a system, and use case diagrams, to model its dynamic behavior. Together, the full set of UML diagrams can be used to fully specify, construct, and document the artifacts of a system [7]. Some other activities that can benefit from UML are system visualization and analysis, model execution for simulation, and testing. Among the different types of diagrams in UML, class diagrams, used to specify the static structure of a system, are the most widely adopted.\n\n2.1.1 Class Diagrams\n\nClass Diagrams (CD) in UML specify the static structure of a system. A class diagram shows the elements of a system, their relationships, and their internal structure. Many of the elements described in a class diagram can be mapped to a counterpart concept found in the Object-Oriented programming languages, such as classes, inheritance relationships, data types, class attributes, packages, interfaces, etc. But some\nelements may describe a high level of abstraction that have no direct counterpart in object oriented programming languages, such as association’s in UML.\n\nIn a class diagram, a Class is represented by a rectangle with three compartments. The name of the class is shown in the top compartment, a list of attributes is placed on the middle compartment, and a list of operations is placed in the bottom compartment. Figure 2.1 shows an example of a class named LoyaltyAccount with these three sections. In the middle section we have a list of two attributes, points, and number, and the last section shows one operation, earn(). The middle and bottom compartments are optional. Some designs with a high level of abstraction may only require the name of the classes in the system.\n\n![LoyaltyAccount class diagram]\n\nFigure 2.1: UML class with two attributes and one operation.\n\nIn the middle compartment of the class, each attribute is shown in a separate line. An attribute definition includes an optional access modifier, “+” or “-” for public or private respectively, followed by the name of the attribute and its type, separated by a colon. An attribute declaration can optionally define a default value by appending “= value” at the end of the attribute definition. Also, attributes can be marked as derived, meaning that their value is calculated at runtime using information from other attributes in the model. Similarly, the third compartment lists on each line an operation. The operation definition includes an access modifier, the name of the operation, the list of parameters between parenthesis with the format “name : type”, and the operations return type. The list of parameters is optional, as well as the return type. In the case of class names and operation names, the identifier can be italicized to signify that the class or operation is abstract.\n\nAnother major element in a class diagram is the inheritance relationship that\nmodels the same inheritance concept found in object oriented programming. The inheritance relationship is modeled with a solid line and a closed arrow head next to the parent class. Figure 2.2 shows an example of the inheritance relationship. This example shows a parent class *Vehicle*, and two sub-classes, *SportsCar*, and *SUV*. As it can be observed in Figure 2.2, UML class diagrams support multiple inheritance, a concept not supported by some programming languages, such as Java.\n\n\n\nThe next modeling element in a class diagram is the *association*. An association represents a kind of relationship between two elements in the diagram, e.g., classes. An association can be further defined with some properties, such as navigability, and multiplicity. Navigability on an association relationship is used to specify the accessibility of class instances. Navigability is represented by an arrow on the navigable end, if both ends are navigable, the arrows are normally omitted. Navigability is defined by the UML specification as follows: “Navigability means instances participating in links at runtime (instances of an association) can be accessed efficiently from instances participating in links at the other ends of the association. The precise mechanism by which such access is achieved is implementation specific. If an end is not navigable, access from the other ends may or may not be possible, and if it is, it might not be efficient. Note that tools operating on UML models are not prevented from navigating associations from non-navigable ends.” [7]. Thus, an association can be\neither bi-directional or uni-directional. In a uni-directional association, only instances that participate in one of the ends of the association can be efficiently accessed from instances participating in links at the other end. As an example, Figure 2.3 shows a class diagram composed by two classes, *Company*, and *Client*. The classes are related by a bi-directional association, this means instances of both classes can efficiently access instances of the class in the opposite end. Figure 2.4 shows an example of a uni-directional association, modeled with a solid line and an arrow head in one of its ends. In this example, the arrow head next to class *Client* indicates that instances of class *Company* can efficiently access instances of class *Client*, while instances of class *Client* can’t efficiently access instances of class *Company*.\n\nAn association can also be annotated with a role name and multiplicity. The role name indicates how the relationship will be known to an instance of the class. For example, for class *Company*, the relationship with class *Client* will be known as *clients*. The multiplicity element indicates how many instances of class *Client* can be related to an instance of class *Company* and how man instances of class *Company* can be related to an instance of class *Client*. The multiplicity can be defined by an exact value or a range composed by a lower bound and an upper bound. An upper bound can also be defined with an asterisk “*” that indicates an unbounded upper multiplicity. In Figure 2.3, the multiplicity “0..2” next to *Client* indicates that an instance of *Company* can be related to “0” or at most “2” instances of *Client*. The “*” next to *Company* indicates that an instance of *Client* can be related to “0” or more instances of *Company*.\n\n\n\nFigure 2.3: Class diagram with bi-directional association.\n2.2 Object Constraint Language\n\nAs previously mentioned, a class diagram can only be used to specify the static structure of a system. As a result, the Object Constraint Language (OCL) [8] has been proposed to support UML and can be used to express pre or post-conditions and class invariants. The Object Constraint Language is used in the UML metamodel specification to define a set of well-formedness rules and constraints, and its introduction arose from the need to describe additional constraints about the objects in the model [8]. Usually, without a formal language, these constraints would be defined in natural language. OCL is a formal specification language that is guaranteed to have no side effects; the evaluation of an OCL expression only returns a value, and it is a typed language, where each expression has a type.\n\nTo illustrate the need of OCL as a specification language, we’ll use the example presented by Warmer et al. [12]. Consider the class diagram in Figure 2.5, in this diagram, the association between class Flight and Person indicates that a flight can have zero or more passengers, indicated by the multiplicity of “0..*”. This indicates that an unlimited number of passengers can be part of the flight, but in reality the number of passengers should be limited by the number of seats in the airplane. To express this constraint, we use the OCL in Listing II.1. OCL can also be used to query the system, specify pre or post-conditions of operations, and specify invariants on classes.\n\n```\ncontext Flight\ninv: self.passengers->size() <= self.plane.numberOfSeats\n```\n\nListing II.1: Flight OCL constraint.\nFigure 2.5: Flights class diagram without OCL.\n\nOne of the characteristics of an OCL expression is that it must be defined in the context of a class. In the example just introduced, the context is class Flight and the inv keyword indicates that the constraint is a class invariant, i.e., it must be satisfied by any instance of class Flight throughout its lifetime. The Object Constraint Language provides a wide variety of predefined functions and logic expressions designed to work in different data types, such as collection functions, iterators, and casting operations among others [8], which makes it a very powerful language for constraints specification. In the following subsections we introduce some of the most used types of expressions available in the OCL language.\n\n2.2.1 Initial Values\n\nInitial values can be used to define default values for attributes or association ends in the diagram [12]. In an initial value definition, the context is the name of the class followed by the name of the attribute being initialized. Next, the value is given as an expression after the keyword init. Note that the expression type must match the type of the attribute being initialized. In a similar way, OCL can be used to define the value of a derived attribute or association end by replacing the keyword init with derived.\n\n```ocl\nclass Person::isAlive\n```\n2.2.2 Query Operations\n\nQuery operations are used to define operations that return a value and do not modify the system [12]. To define a query, the context is defined by the class name, operation name, parameters, and return type, and the expression is defined with the keyword body. A query operation without parameters can be seen as a derived attribute where only the context declaration varies. The following example shows the definition of a query operation. In this example, the return type is defined as a Set with elements of type Service. In the body expression, the collection deliveredServices is converted to a set with the operation ->asSet() before being returned by the operation.\n\n\\[\n\\text{context LoyaltyProgram::getServices(): Set(Service)} \\\\\n\\text{body: partners.deliveredServices->asSet()}\n\\]\n\n2.2.3 Attributes and Operations Definition\n\nOCL can also be used to define attributes and operations, beyond the ones already defined in the model. Attributes and operations defined with OCL are derived attributes and query operations respectively. The context is the class where the attribute or operation is being defined. The definition is done with the keyword def followed by the name of the attribute or operation and its definition. In the following example, an operation is defined using the operation select. This operation selects elements that satisfy a Boolean expression. As illustrated in this example, \\( shift = s \\) indicates that we want to select all the employees where \\( shift \\) is equal to the parameter \\( s \\).\n2.2.4 Invariants\n\nAn invariant is a rule attached to a class that must be satisfied by all of its instances during their lifetime [12]. As explained in an earlier example, an invariant includes the context followed by the keyword `inv` and a Boolean expression. The following example shows an invariant for class `Person`. In this example, keyword `self` is used to refer to the contextual instance, i.e., any instance of `Person`. Note that the use of `self` is optional, as seen in previous examples.\n\n`context Person\ninv: self.age < 150`\n\n2.2.5 Preconditions and Postcondition\n\nAs mentioned earlier, another use of OCL is the specification of pre or post-conditions. An OCL post-condition for a method specifies a set of constraints that must be maintained after the execution of the method. This means, the result returned by the method and the resulting program state must satisfy the constraints defined by the OCL expression. An OCL post-condition definition includes a context declaration, which is composed by the name of the class and the name of the method, followed by the constraint. As an example, Listing II.2 shows a post-condition for method `updateIncome()` in class `Person`, with the constraint `self.income = newIncome`, indicating that the value of field `income` in class `Person` must be equal to the value of the parameter `newIncome` after the execution of the method.\n\n`context Person::updateIncome(newIncome: Integer): Boolean`\npost: self.income = newIncome\n\nListing II.2: OCL post-condition expression.\n\n2.3 Model Driven Architecture\n\nModel Driven Architecture (MDA) describes a software development approach where models are used as the primary source for software development. Some of the advantages or objectives when using MDA include portability, quality, maintenance, and improved testing and simulation. The following subsections introduce MDA’s terminology, followed by an overview of the MDA approach.\n\n2.3.1 Terminology\n\nThe terms introduced by MDA are in the context of an existing or planned system [6], a system can be a program, a single computer system, or a combination of different types of systems. A model of a system is a “description or specification of that system and its environment for some certain purpose. A model is often presented as a combination of drawings and text. The text may be in a modeling language or in a natural language.” [6]. In the context of MDA, the specification is considered to be formal, meaning that the specification is “based on a language that has a well-defined semantic meaning associated with each of its constructs, to distinguish it from a simple diagram showing boxes and lines.” [13]. Thus, Model Driven Architecture describes an approach where models are used as the main source for software development, which includes documenting, analyzing, designing, constructing, and maintaining a system [6]. An application refers to the functionality being developed. And the architecture of a system is a specification of the parts and connectors of the system and the rules for the interactions of the parts using the connectors. Each of these parts, connectors and rules of a system are represented as a set of interconnected models,\nin the context of MDA [13].\n\nA viewpoint on a system “is a technique for abstraction using a selected set of architectural concepts and structuring rules, in order to focus on particular concerns within that system” [13]. In the context of modeling, abstraction is a technique in which details are removed in order to simplify the model. The type or level of abstraction will determine the details that are of interest in a particular model. A view of a system is a specific representation of a chosen viewpoint, a viewpoint can be represented by one or more views. A platform is a set of technologies and functionality which an application can use without concern for how the functionality provided by the platform is implemented [6], and platform independent is a characteristic of a model indicating that the model is independent of the features of any given platform.\n\nMDA explicitly defines three types of viewpoints with their corresponding models or views. The computational independent viewpoint “focuses on the environment of the system, and the requirements for the system; the details of the structure and processing of the system are hidden or as yet undetermined” [6]. And its corresponding model is the computation independent model (CIM). The CIM model serves as a domain model, and it mainly defines the requirements without concerns about specific details of the models or artifacts used to realize them. Next, the platform independent viewpoint focuses on the operation of a system, while hiding the detail necessary for a specific platform [6]. The platform independent model viewpoint must define the area of the system that does not change in different platforms. The platform independent model (PIM) serves as its view. Typically, a PIM is designed against a generic or neutral virtual machine, independent of any particular platform. The last viewpoint is a platform specific viewpoint, in which details about a specific platform are included, and its corresponding view is the platform specific model (PSM).\n\nA key aspect of MDA is the use of model transformations. A model transformation is the process of converting one model into another, such as a PIM to a PSM. How\nthe transformation is done depends on a set of mapping or transformation rules [13]. Finally, an implementation “is a specification, which provides all the information needed to construct a system and to put it into operation” [6].\n\n2.3.2 MDA Process\n\nThe MDA process starts with the specification of the system requirements with a computational independent model (CIM). The CIM defines the domain model and business rules and hides most of the details about how the data is processed or how the system is implemented. The CIM provides the vocabulary that will be shared and used by the rest of the models [6]. Next, a platform independent model is constructed (PIM) via UML, and it can finally be transformed into one or more specific platforms. Note that the MDA process is not restricted to vertical transformations across the different layers of abstraction (CIM, PIM, PSM), horizontal transformations may also occur. As an example, within PSM, a JUnit test model can be generated from a Java class model [13]. Also, a PSM model can take the role of PIM and be used for further transformations. In general, the key concepts of MDA are models and transformations, such as the transformation of a UML diagram to Java code. The MDA pattern can be visualized in Figure 2.6, taken from [13].\n\n\n\nCentral to the model transformation phase is the concept of transformation mappings. MDA transformation mappings specify how an element in a particular model maps to an element in a different model. A mapping can also define marks. A mark is a particular attribute that labels elements and further defines how the transformation is carried out. Mapping can also include templates, to specify particular kinds of transformations [6]. After a model has been marked, the final step is the transforma-\ntion where the input is a marked PIM and the output is a PSM. Finally, a PSM can be translated to code. In some instances, a direct transformation from a PIM to code can be supported. The transformation process is shown in Figure 2.7 taken from [6]. There are multiple approaches that can be used for model transformation. One such approach is the one previously mentioned and shown in Figure 2.7 that makes use of markings. Other approaches include metamodel and model transformations with transformations specifications, pattern transformations, and model merging.\n\n\n\nA variety of technologies have been adopted to support the MDA approach, this include the Unified Modeling Language (UML), the standard modeling language for specification and visualization, the Meta-Object facility, a model repository that can be used to specify model manipulation standards, and Profiles, used as UML extension mechanisms.\n\n### 2.3.3 UML to Java\n\nTo illustrate the MDA process, we will use a model transformation example from a UML class diagram (PSM) to a Java program (Code). This type of transformation is commonly known as forward engineering, an important part of the Model Driven Architecture that greatly expedites the development process by automatically generating a skeletal program the developers can extend. As previously explained, the translation process takes a source model and a set of transformation rules to produce...\na target model. Figure 2.8 shows the diagram for our specific example. As transformation rules we will use the ones defined by the forward engineering tool Rational Software Architect [14]. The rules are shown in Table 2.1. As source model, we will use the class diagram shown in Figure 2.9.\n\n\n\nTable 2.1: RSA transformation rules.\n\n<table>\n<thead>\n<tr>\n<th>Class Diagram Element</th>\n<th>Java Element</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Class</td>\n<td>Java Class</td>\n</tr>\n<tr>\n<td>Property</td>\n<td>Class Field (with setter and getter methods)</td>\n</tr>\n<tr>\n<td>Operation</td>\n<td>Class Method</td>\n</tr>\n<tr>\n<td>Association</td>\n<td>Class Field (with setter and getter methods)</td>\n</tr>\n<tr>\n<td>Type</td>\n<td>Java Equivalent Type</td>\n</tr>\n</tbody>\n</table>\n\n\n\nFollowing the transformation rules, the three classes in the diagram will be mapped to three Java classes of the same name. Also, properties are mapped to class fields with their respective get and set methods. Figure 2.10 shows the generated Java code for classes and attributes. Since associations in a class diagram do not have a direct counterpart in most programming languages, they are usually mapped to fields in the\nFigure 2.10: Code generated for classes and properties.\n\nclasses that are linked by the association. Looking at the association between Bank and Client, the transformation creates a field named clients in class Bank and a field named banks in class Client. For uni-directional associations, such as the one between class Client and Account, only one field for the navigable end is generated. In this specific example, the transformation does not generate code to enforce the multiplicity constraints of an association; it is the developers responsibility to implement them. Figure 2.11 shows the generated Java code for associations. Finally, operations are mapped to empty method declarations on their respective classes, leaving their final implementation to developers. Figure 2.12 shows the generated Java code for the operations in the diagram.\n\n2.4 Symbolic and Dynamic Symbolic Execution\n\nSymbolic execution is a testing technique where instead of executing a program it is symbolically executed for a set of classes of inputs [15]. In the other hand,\npublic class Bank {\n ... \n private List<Client> clients;\n public List<Client> getClients() {\n return clients;\n }\n public void setClients(List<Client> clients) {\n this.clients = clients;\n }\n private List<Account> accounts;\n public List<Account> getAccounts() {\n return accounts;\n }\n public void setAccounts(List<Account> accounts) {\n this.accounts = accounts;\n }\n}\n\npublic class Client {\n ... \n private List<Bank> banks;\n public List<Bank> getBanks() {\n return banks;\n }\n public void setBanks(List<Bank> banks) {\n this.banks = banks;\n }\n private List<Account> accounts;\n public List<Account> getAccounts() {\n return accounts;\n }\n public void setAccounts(List<Account> accounts) {\n this.accounts = accounts;\n }\n}\n\nclass Account {\n ... \n public Double withdraw(Double a) {\n // TODO\n return null;\n }\n}\n\nFigure 2.11: Code generated for associations.\n\nFigure 2.12: Code generated for operations.\ndynamic symbolic execution is a combination of concrete and symbolic execution. The following subsections introduce terminology related to dynamic and symbolic execution and an overview of each approach.\n\n2.4.1 Symbolic Execution\n\nDuring symbolic execution, the execution semantics is changed for symbolic execution by introducing symbolic names that are used to represent the program inputs. This is, each input value is replaced by a symbolic variable, e.g., $\\alpha_1$, and program inputs are eventually assigned to program variables. With the introduction of symbols, the arithmetic expressions used in assignment and IF expressions are extended to support them. As a result, the right hand side of an assignment is expressed as a polynomial expression over the symbols introduced, i.e., \\{$\\alpha_1, \\alpha_2, ...$\\}. The state of a program execution includes the variables with their values as a symbolic expression, a statement counter, and the path condition (pc) [15]. The path condition is a Boolean expression over the symbolic inputs, e.g., $\\alpha_1 + \\alpha_2 > 0$. A path condition is “the accumulator of properties which the inputs must satisfy in order for an execution to follow the particular associated path. Each symbolic execution begins with pc initialized to true. As assumptions about the inputs are made, in order to choose between alternative paths through the program as presented by IF statements, those assumptions are added (conjoined) to pc” [15].\n\nUnlike a concrete execution, the result of a symbolic execution is equivalent to a set of test cases, where each symbolic value represents a class of concrete values. In symbolic execution, “the class of inputs characterized by each symbolic execution is determined by the dependence of the program’s control flow on its inputs” [15]. During symbolic execution, all possible execution paths are explored, except on the presence of unbounded loops, where the number of iterations is bounded. Table 2.2 shows an example of symbolic execution of method \\texttt{divide()} in Figure 2.13. At each statement,\nthe table shows the current symbolic value for each of the variables involved in the method’s execution. Input parameters are immediately assigned a symbolic value, e.g., \\( a_1, b_1 \\) respectively, while for other variables their value is unknown until an assignment occurs. The table shows two possible execution paths as *cases*, each case shows a path condition that describes a particular symbolic execution. In this example, one where the evaluation of the *if* statement is *true*, and one where the evaluation is *false*. For example, the path condition \\( b_1 > 0 \\) represents all the test case values where parameter \\( b \\) has a value greater than 0.\n\n```java\npublic static divide(int a, int b){\n int result = 0;\n if(b>0){\n result = a/b;\n }else{\n result = a;\n }\n}\n```\n\nFigure 2.13: Example method for symbolic execution.\n\n<table>\n<thead>\n<tr>\n<th>Statement</th>\n<th>a</th>\n<th>b</th>\n<th>result</th>\n<th>PC</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>( a_1 )</td>\n<td>( b_1 )</td>\n<td>?</td>\n<td>true</td>\n</tr>\n<tr>\n<td>2</td>\n<td>-</td>\n<td>-</td>\n<td>0</td>\n<td>-</td>\n</tr>\n<tr>\n<td>case ( \\neg \\ (b > 0) )</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>( \\neg \\ (b_1 > 0) \\land true )</td>\n</tr>\n<tr>\n<td>3</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n</tr>\n<tr>\n<td>6</td>\n<td>-</td>\n<td>-</td>\n<td>( a_1 )</td>\n<td>-</td>\n</tr>\n<tr>\n<td>8</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n</tr>\n<tr>\n<td>case ( b > 0 )</td>\n<td>-</td>\n<td>-</td>\n<td>( a_1 / b_1 )</td>\n<td>( b_1 > 0 \\land true )</td>\n</tr>\n<tr>\n<td>3</td>\n<td>-</td>\n<td>-</td>\n<td>( a_1 / b_1 )</td>\n<td>( b_1 > 0 \\land true )</td>\n</tr>\n<tr>\n<td>4</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n</tr>\n<tr>\n<td>8</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n</tr>\n</tbody>\n</table>\n\nTable 2.2: Symbolic execution example.\n\nOne of the key aspects of a symbolic execution technique is the ability to determine the decidability of the generated path conditions, i.e., whether a particular execution path is feasible or not. In some instances, when working with complex path conditions, this may introduce a decidability problem, when current SAT solvers are not able to successfully evaluate the satisfiability of an expression. Another problem of symbolic\nexecution arises with the introduction of loops that could lead to infinite unfolding. Dynamic symbolic execution tries to alleviate these issues while taking advantage of the symbolic execution.\n\n2.4.2 Dynamic Symbolic Execution\n\nDynamic symbolic execution is a combination of a concrete execution and symbolic execution. Dynamic symbolic execution starts by executing a program with a specific input while also performing symbolic execution. The constraints or path conditions generated are then used by a constraint solver to decide the next execution, usually forcing the program to follow a different execution path by flipping a sub-expression in the path condition and generating the appropriate input. One of the advantages over symbolic execution is that in the presence of complex symbolic expressions where a constraint solver is unable to produce a result, the concrete values and observed execution can be used to simplify the expression, keeping the constraints decidable [16].\n\nTable 2.3 shows an example of dynamic symbolic execution, with concrete values 5, 3, for \\( a \\) and \\( b \\) respectively. Unlike symbolic execution, there is only one case that corresponds to the actual concrete execution.\n\nTable 2.3: Dynamic symbolic execution example.\n\n<table>\n<thead>\n<tr>\n<th>Statement</th>\n<th>( a )</th>\n<th>( b )</th>\n<th>Result</th>\n<th>PC</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>( a_1 )</td>\n<td>( b_1 )</td>\n<td>?</td>\n<td>true</td>\n</tr>\n<tr>\n<td>2</td>\n<td>-</td>\n<td>-</td>\n<td>0</td>\n<td>-</td>\n</tr>\n<tr>\n<td>3</td>\n<td>-</td>\n<td>-</td>\n<td>( a_1 / b_1 )</td>\n<td>( b_1 > 0 \\land true )</td>\n</tr>\n<tr>\n<td>4</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n</tr>\n<tr>\n<td>8</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n</tr>\n</tbody>\n</table>\n2.5 Software Verification\n\nConsistency checking between a UML class diagram and its Java implementation can be done either with formal verification or testing-based validation techniques. Software verification can be defined as “the process of determining whether the products of a given phase of the software development process fulfill the requirements established during the previous phase” [9]. In a more general sense, verification tries to find out if a program satisfies one or more properties, such as pre or post-conditions or assertions [17]. One approach for software verification is model checking, an approach that employs state-space exploration to exhaustively and automatically check whether a software system satisfies a given specification. This is usually done by exploring all possible program states within a bound using static analysis, while checking that each state satisfies a predefined set of properties [18].\n\nWhile effective at determining if a software system satisfies a given specification, due to the increasing complexity of software systems, formal verification often does not scale effectively to real world applications due to state-space explosion, i.e., exhaustively generating all possible states in large systems becomes impractical. One way to alleviate the state-space explosion problem is to perform model based verification with bounded space exploration, such as bounding the depth of the search [19, 20]. A bounded approach scales more effectively to real world application, since it effectively limits the state-space that needs to be explored. However, bounded model based verification is not as effective since not all the program states are checked, i.e., bounded model based verification can only show the presence of bugs but not their absence.\n\n2.6 Program Testing\n\nUnlike software verification, program testing is a form of dynamic analysis in which the program is executed to check if the resulting state satisfies a set of requirements.\nCentral to program testing is the use of test cases. A test case is composed by four elements. The first element is the test case values, or some input that allows the program to execute successfully. The second element is a set of expected results, also called oracles, which are compared to the resulting state after the execution to determine if it was successful. The third element is a set of prefix values, any values necessary to initialize the system in to a state where it can receive the test values. And fourth, postfix values, needed to complete the execution and evaluation of the software under test [9].\n\nProgram testing offers some advantages over verification. One of them is the ability to instrument a program, allowing for a more flexible test case generation process aimed at achieving different types of coverage criteria. Program instrumentation is a code modification activity in which extra code is added to the original program to monitor its execution or modify its behavior as needed. In the context of software testing, instrumentation is typically used to monitor the program execution to determine the execution path (which statements are executed) of a particular test case. Execution paths can be used by a testing procedure to determine how to generate further test cases using coverage criteria. In the scope of program testing, coverage criteria is used to define program execution coverage goals, such as branch coverage, where different control statement branches must be covered by the execution of multiple test cases [9].\n\nAnother advantage of program testing is that requirements can be more easily designed. In some instances requirements can be automatically generated from the program or program’s model, e.g., class diagram, simplifying the testing activities considerably. However, unlike model based verification techniques, program testing can only show the presence of bugs, but not their absence, since in most scenarios, program testing can only cover a subset of all possible test cases. This is, when testing non-trivial programs it is unfeasible to exhaustively generate all possible test cases.\nA trade-off when the complexity of some programs turn model based verification an unfeasible approach.\n\nIn the context of consistency checking, traditional program testing has also some limitations. One of the limitations is that traditional testing techniques assume that the execution of a faulty statement can expose a software fault, and rely on different coverage criteria to cover as much statements as possible. Unfortunately, some errors cannot be exposed based on this assumption. If there is not an asserting statement, the error may not be exposed, even after executing the faulty statement. Consider the code in Figure 2.14, introduced by Ammann et al. [9].\n\n```java\npublic static int numZero (int[] x) {\n // Effects: if x = null throw NullPointerException\n // else return the number of occurrences of 0 on x\n int count = 0;\n for(int i=1; i < x.length; i++){\n if(x[i]==0){\n count++;\n }\n }\n return count;\n}\n```\n\nFigure 2.14: Sample code for traditional testing.\n\nThe method calculates the number of zeros in array \\( x \\). In this example, the programmer forgot to check the first element of the array in the \\( for \\) loop. The statement at line four, “\\( for(int i=1; ...) \\)”, should be, “\\( for(int i=0; ...) \\)”. If the method is executed with the input “\\( [2, 7, 0] \\)”, no error is exposed when the faulty statement is executed. A coverage criteria approach is not sufficient to uncover the error.\n\nAnother limitation of traditional program testing is that most techniques rely on flipping conditional branches during the execution of the program to reach different statements and achieve the desired coverage criteria. However, in MDE, some forward engineering tools translate a class diagram to a program that has auxiliary fields that if flipped can cause undesired behavior. For instance, in the Eclipse Modeling Framework (EMF) [21], the attribute \\( eContainerFeatureID \\) is introduced as an auxiliary field. This attribute is an integer used to identify a container and specify whether it is a navigable feature or not by assigning a positive (navigable) or negative value.\nIf the value of $eContainerFeatureID$ is altered to cover a different execution path, a false positive may be reported.\n\n2.7 Model Based Testing\n\nMost model-based testing techniques consider the generation of test cases from behavioral models [22, 23, 24, 25, 26, 27, 28, 29] such as activity or sequence diagrams. As an example, Khandai et al. proposed a technique for generating test cases for concurrent systems using sequence diagrams [22]. In their approach, a UML sequence diagram, showing all possible interactions or sequence of message exchanges between objects, is used to automatically generate a set of test cases that represent the interactions defined in the model. In a similar way, the work by Cartaxo et al. uses UML sequence diagrams with labeled transition systems for test case generation [29].\n\nAn approach by Anbunathan et al. [30] makes use of some of the static information contained in the system’s class diagrams, such as class names, and associations, but it ultimately relies in the use of state diagrams for the test case generation.\n\nIn general, existing model-based testing techniques can be classified into two categories. In state-based approaches the system behavior is described by state machines. Abdurazik et al. proposed an approach to generate test cases based on UML collaboration diagrams to perform dynamic and static testing [31]. And the second category uses scenario-based descriptions of interactions between different system entities. Roychoudhury et al. proposed a new notation, called symbolic message sequence charts, that generates test cases for process classes [32]. A verification tool for Java [33] considers OCL and JML as assertion languages to specify pre or post-conditions on a Java program, and it applies a verification approach to determine if the implementation is consistent with the specification. As far as we know, no prior work has been proposed to support consistency based testing of programs against UML class diagrams.\nAnother area of interest is consistency checking between different types of models or specification attributes [34, 35, 36, 37], but they do not support consistency between a model and its final implementation. As an example, the work by Sabetzadeh et al. introduces a technique in which two sets of models are merged and then checked against a set of requirements to determine their consistency [35]. In other instances, these approaches utilize a set of transformations or model merging techniques to match elements between different types of models [35, 37]. As an example, the work by Liu et al. [38] introduces an MDA test case generation approach that employs model to model transformations. Their approach relies in transformation rules between structural features, and does not consider behavioral specification such as OCL post-condition.\n\nReverse engineering techniques have also been applied to check some specific UML properties, such as class diagram association properties. Work by Gueheneuc et al. [39] and Milanova et al. [40] recovers UML composition from a program based on the non-accessibility property. However, this property is not required by the UML specification. Their approach focuses in four properties: exclusivity, invocation site, lifetime, and multiplicity. In terms of the lifetime property, their approach applies the object ownership model which doesn’t fully comply with the UML composition.\n\nThe ownership model enforces the non-accessibility property, i.e., a part object is not allowed to be used outside of its owner object. According to the non-accessibility property, the implementation in Figure 2.15 (b) is not a composition, since instances of class \\( B \\) (owned class) can be accessed from the outside. However, the UML specification allows a third-party object to access an owned object directly. Therefore, the definition of composition based on the exclusivity property is not consistent with the UML specification. In Figure 2.16 we can see a fragment of the UML metamodel where the metaclass \\textit{Association} has an association to the owned metaclass \\textit{Property}. This means that an instance of metaclass \\textit{Association} can access instances of owned\nFigure 2.15: Two composition implementations.\n\nAs a result, the application of a composition property that follows the ownership model would require considerable adaptations to existing modeling tools.\n\nBarbier et al. [41] introduced a formal specification of the whole-part relationship which includes the composite property. The specification uses the Object Constraint Language (OCL) and it is based in the addition of new metaclasses to the UML specification. Unfortunately, the introduction of new metaclasses renders existing modeling tools incompatible with their approach. As a result, the use of their specification, although effective in precisely defining the whole-part relationship, becomes too restrictive given that the required adaptations on existing tools are in most cases not feasible. The work presented by Milicev [42] in the other hand introduces a formal specification of the UML association properties using the Z notation specification.\nlanguage, but their specification doesn’t include the composite property.\nCHAPTER III\n\nBOUNDED EXHAUSTIVE TESTING\n\nIn object oriented programming, the basic building blocks are objects that collaborate with each other to achieve a high level behavior [11]. This collaboration is achieved through interactions, such as method invocations, that establish relationships between objects. These relationships allow them to contribute to the overall behavior of the system; an object in isolation would be of no value. In this scenario, the desired behavior of a system can only be achieved if the objects interact as expected.\n\nIn UML, an association is used to identify the semantic relationship between two classes, i.e., it defines the types of interactions that are possible between objects that are instances of those two classes. An incorrect implementation of UML associations would result in objects interacting in unexpected ways, and as mentioned previously, in object oriented programming, the correct functioning of a program is highly dependent on objects interacting as expected. Because of this, maintaining the consistency between an implementation and its design model is an important challenge. To illustrate our approach we will use the UML composition as an example.\n\nUML composition, as a subtype of a whole/part relationship, can be defined in terms of two properties; lifetime and shareability. The lifetime property indicates that an element is composed by one or more parts, and such element is responsible of\nthe lifetime of its parts, i.e., if the element is deleted, all of its parts are deleted. For\nthe shareability property, a part element cannot be part of more than one element\nat a time. In a class diagram, UML composition is represented as a solid/filled black\ndiamond. Figure 3.1 shows an example of a UML composition relationship between\nclass Company, known as owner class, and class Division, known as owned class.\nThe relationship indicates that a company is composed by zero or more divisions. If\na particular company is deleted, the divisions that compose such company are also\ndeleted (lifetime property). Also, a particular division cannot be part of more than\none company at a time (shareability property).\n\nA program that implements the UML composition but fails to satisfy the lifetime\nproperty can cause serious consequences at runtime, such as trying to access an object\nthat no longer exists or memory leak problems when memory from unused objects\ncannot be correctly reclaimed by garbage collectors. Also, divergences between a\ndesign model and its implementation can lead to a failure to satisfy or effectively\ntrace requirements during the development process.\n\nThe example in Figure 3.2 shows a scenario with an incorrect composition im-\nplementation. In this example, the destroy() method fails due to the condition in\nthe for statement in line 12 \"i > d.getClients.size() - 1\", where the reference to the\ninstance of class Division that is being destroyed is not removed from the last Client\nin the collection. Because of this, the code in the main() method causes a NullPointerException\nwhen trying to invoke the method getName() on the instance of class\nCompany that was previously destroyed.\nprivate List div;\nprivate String name;\npublic void setDiv(Division d) { ... }\npublic Division getDiv() { ... }\npublic String getName() { ... }\npublic void setName() { ... }\npublic void destroy() {\n Iterator divisionIt = div.iterator();\n while(divisionIt.hasNext()) {\n Division d = (Division) divisionIt.next();\n for(int i=0; i < d.getClients().size() - 1; i++) {\n Client c = d.getClients().get(i);\n c.setDivisions(null);\n }\n d.setCmpy(null);\n }\n setDiv(null);\n}\n\npublic class Division {\n private Company cmpy;\n private List clients;\n public void setCmpy(Company c) { ... }\n public Client getCmpy() { ... }\n public void setClients(Client c) { ... }\n public Client getClients() { ... }\n}\n\npublic class Client {\n private List divisions;\n public void setDivisions(Division d) { ... }\n public List getDivisions() { ... }\n}\n\npublic class Test {\n public static void main(String args[]) {\n Company c = new Company();\n Division d = new Division();\n c.setDiv(d);\n Client cl = new Client();\n cl.setDivisions(d);\n ... \n c.destroy();\n ... \n for(int i=0; i<cl.getDivisions().size; i++) {\n Division d1 = cl.getDivisions().get(i);\n System.out.println(d1.getCmpy().getName());\n // NullPointerException\n }\n }\n}\n\nFigure 3.2: Exception caused by an incorrect composition implementation.\n3.1 Overview\n\nTo detect inconsistencies between a design model and its implementation our approach provides a method to test whether the implementation enforces a set of OCL constraints derived from the design model in terms of the UML association properties. Our approach overview is shown in Figure 3.3 and it is explained in the following sections.\n\n3.1.1 Input\n\nOur approach takes as input a class diagram and a Java program that must be an implementation of the class diagram. As an example, the class diagram in Figure 3.1 and the implementation in Figure 3.2 serve as input. The implementation can be a combination of code automatically generated by forward engineering tools and code manually added by developers to implement any features not supported by the tool, such as composition associations.\n\n3.1.2 General Steps\n\nAs a first step, using information from the class diagram, we generate a set of OCL constraints for each of the UML association properties, the OCL constraints are generated using a set of templates that are introduced in Appendix A. Next, the\nprogram is instrumented to gather some information, such as fields being accessed during execution. This information will be used during the testing process, explained in Section 3.1.4. The instrumentation is guided by the generated OCL constraints. The instrumented program, class diagram, and the generated OCL constraints are then used during the program testing phase. During the program testing phase, we generate a set of instances, used as test cases, to which we apply the previously generated OCL constraints to try to detect possible violations of any of the UML association properties. The process is explained in detail in Section 3.1.4 using the composition property as an example.\n\n### 3.1.3 Formalization of UML Associations\n\nThe Unified Modeling Language (UML) [7], a popular modeling language used in software development projects, provides a set of diagrams that can be used to model the static and dynamic aspects of a system. Among these diagrams, class diagrams are used to define the static structure of the system. Some of the concepts introduced in a class diagram, like inheritance, can be easily mapped to most object oriented programming languages. Unfortunately, other concepts, such as associations, have no direct counterpart in the syntax and semantics for programming languages. As a result, while there exist many forward engineering tools which help generate code from a class diagram they often leave some implementation to the users, or in some cases they implement them in a way that does not fully follow the semantics defined by UML.\n\n\n\n**Figure 3.4: A UML Class Diagram.**\n\nA UML class diagram includes a set of classes and the relationships among them.\nFigure 3.4 shows a class diagram with two classes: *Division*, and *Client*. The relationship between classes is denoted by associations, i.e., a line connecting two classes, and each association is marked with a set of properties at each end (member end) that further defines the type of relationship. Thus, an association in a UML class diagram is used to specify a semantic relationship between classes, i.e., the relationship meaning and possible restrictions. An association must have at least two ends, each end connected to a class [7]. For example, the association between class *Division* and *Client* in Figure 3.4 shows that a division can be related to any number of clients, indicated by the “*” next to class *Client*, and also shows that a client can be related to 1 or 2 divisions, indicated by “1..2” next to class *Division*.\n\nAn instance of a class diagram can be represented by a UML object diagram. An example of an instance of the class diagram in Figure 3.4 is show in Figure 3.5 (b). The figure also includes the class diagram to show the instantiation relationship. The object diagram shows an instance of class *Division* named *motors* related to an instance of class *Client* name *ford*. In an object diagram, an instance of an association is called link and is represented by a single line. A link in an object diagram, unlike an association, does not include any properties.\n\n\n\nFor an object diagram to be considered valid, it must follow the restrictions indicated in the class diagram it instantiates. The object diagram in Figure 3.5 (b)\nis valid since it does not violate any of the restrictions in the class diagram, e.g., the maximum number of relationships between the instances of classes *Division* and *Client*. The example in Figure 3.6 however, shows an invalid object diagram since the instance of class *Client* has a link to more than two instances of class *Division*.\n\n\n\nIn a similar way, the UML specification provides a set of diagrams that describe the structure and semantics of a valid class diagram, i.e., a class diagram must be a valid instance a UML specification diagrams. Figure 3.7 shows a fragment of the UML specification (a) and an instance (b). A class in a UML specification diagram is called a metaclass. In this example, class *Division* is an instance of metaclass *Class* and the property *isActive* is an instance of the metaclass *Property*. The diagram in Figure 3.7 (a) indicates that an instance of metaclass *Class* can own 0 or more instances of metaclass *Property*.\n\nThe diagrams previously introduced are part of the metadata architecture. The metadata architecture includes four layers, three of which we already used in our previous examples; the information layer (M0) represented by an object diagram, the model layer (M1) represented by a class diagram, and the metamodel layer (M2), also represented as a class diagram that describes the structure and semantics of a valid\nclass diagram at M1 layer. The last layer is the meta-metamodel layer (M3). The information layer includes the data being described, the model layer includes metadata that describes the information layer, the metamodel layer defines the structure and semantics of the metadata and the meta-metamodel layer includes the description and semantics of meta-metadata. The same way an object diagram (M0) represents an instance of a class diagram (M1), a class diagram represents an instance of the metamodel layer (M2). And a diagram at M2 layer represents an instance of the meta-metamodel layer (M3).\n\nThe UML language is defined at the metamodel layer, or M2 layer. The specification includes a set of diagrams at the M2 level that describe the structure and semantics of the M1 layer. The fragment of the UML specification shown in Figure 3.8(M2), includes the metaclasses needed to create an association between two classes at the M1 level. The diagram includes three metaclasses: Class, Property, and Association. The diagram shows that an association must have at least two member ends, denoted by the “2..*” next to metaclass Property, where each member end is a property, and it also shows the relationship between a class and a property, i.e., the property is a class attribute. Figure 3.8(M1) shows an instance of the class diagram at M2 level, where classes Division and Client are instances of metaclass Class. The attributes divisions and clients are instances of metaclass Property, which are refer-\nenced by their respective class via ownedAttribute. The association (the line linking classes Division and Client), is an instance of metaclass Association and it has a reference to the attributes b and c via memberEnd.\n\nFigure 3.8: Four layer metadata architecture\n\nFor an M1 instance, or class diagram, to be valid, it must follow the restrictions of the class diagram at the M2 layer. An example of an invalid instance is shown in Figure 3.9, where the instance of metaclass Association has a reference to one member end b, an instance of metaclass Property. This is a violation since the multiplicity for the memberEnd is “2..*”, meaning that an association must have a reference to at least two instances of metaclass Property. The relationship between the different layers in the context of the Unified Modeling Language is shown in Figure 3.8.\n\nThe UML specification also includes a set of constraints that are applied to the diagrams at M2 level. Some constraints are defined using the Object Constraint\nLanguage (OCL). Having a constraint defined at M2 level means that an instance of the model in the next layer, i.e. M1 level, must satisfy the restriction. As an example, the following OCL constraint is given for the class diagram in Figure 3.8(M2):\n\n\\[\n\\text{context Association} \\\\\n\\text{inv: self.memberEnd} \\rightarrow \\text{exists( aggregation } <> \\text{ Aggregation::none)} \\\\\n\\text{implies self.memberEnd} \\rightarrow \\text{size()} = 2\n\\]\n\nThe constraint states that if a member end exists in the association whose aggregation type is different than none, e.g., aggregation type is composite; the association must have exactly two member ends. The operation \\(\\text{size()}\\) returns the number of elements in the collection \\(\\text{memberEnd}\\). For example, the class diagram in Figure 3.10(a) shows a valid instance of an association with three member ends, i.e., \\(i, c, \\) and \\(it\\). While the class diagram in Figure 3.10(b) shows an invalid instance, since one of the member ends is marked as \\(\\text{Aggregation::Composite}\\) (black diamond), and \\(\\text{self.memberEnd} \\rightarrow \\text{size()}=3\\).\n\nConstraints defined with OCL or other formal languages can be used to auto-\nautomatically validate M1 level instances (M0). Unfortunately, not all constraints are formally defined in the UML specification; some are only described using natural language. For example, the following constraint is found in the specification: “When an association specializes a second association, every end of the specific association corresponds to an end of the general association, and the specific end reaches the same type or a subtype of the more general end.” [7] p.40. As a result, validating that an implementation fully adheres to the model specification becomes a challenging task, since it is hard to automatically process and understand natural language.\n\n3.1.4 Our Approach\n\nTo detect inconsistencies between a design model and its implementation our approach provides a method to test whether the implementation enforces a set of OCL constraints derived from the design model in terms of the UML association properties. Our approach uses as input a class diagram and a Java implementation and it can be divided in two main modules: OCL generation, and program testing. The class diagram is used by the OCL generation module to generate a set of OCL constraints at M1 level for each of the association properties. The OCL constraints generation is done according to the templates presented in Appendix A. Next the program is instrumented and together with the class diagram and the generated OCL constraints is given as input to the program testing module. The program testing module generates a set of instances (test cases) to which it applies the OCL constraints to try to detect possible violations. To illustrate our approach, in the following section we will concentrate on the UML composition property.\n\n3.1.4.1 Detecting UML Composition Violations\n\nTo illustrate our approach to detect violations of the UML composition property, we will consider the program shown in Figure 3.11 that implements the class diagram\nin Figure 3.12. In this class diagram we have a composition association, where the\nowner class is class Company and the part class is class Division. We also have two\nassociations, one between class Division and class Client, and one between class Client\nand class Division. In relation to the composition association, we call class Client a\nthird-party class since it has a relationship to the part class. We call instances of an\nowner class, owner objects, and instances of a part class, part objects. In this example,\nwe omitted the implementation of class University. Also, the code has a reference to\nclass Display; an auxiliary class that displays information about a company and its\nrelationships.\n\n```java\n1 public class Company {\n2 private List div;\n3 private String name;\n4 private Display disp;\n5 public void setDisp(Display d) { ... }\n6 public Display getDisp() { ... }\n7 public void setDiv(Division d) { ... }\n8 public Division getDiv() { ... }\n9 public String getName() { ... }\n10 public void setName() { ... }\n11 public void destroy() {\n12 Iterator divisionIt = div.iterator();\n13 while(divisionIt.hasNext()) {\n14 Division d = (Division) divisionIt.next();\n15 for(int i=0; i < d.getClients().size(); i++) {\n16 Client c = d.getClients().get(i);\n17 c.setDivisions(null);\n18 }\n19 d.setCmpy(null);\n20 }\n21 setDiv(null);\n22 disp.removeObject(this);\n23 disp = null;\n24 }\n25 } \n```\n\nThe execution of a specific sequence of instructions using the code in Figure 3.11\ncan be used to generate a program state that is an instance (M0) of the class diagram\nin Figure 3.12 (M1). As an example, the execution of the instructions in Figure 3.13\nresult in a program state where an instance of class Company has a reference to an\ninstance of class Division. The resulting program state can be represented as an\nobject diagram as it is shown in Figure 3.14.\n\nFigure 3.11: A Java implementation of the class diagram in Figure 3.12.\nFigure 3.12: Class diagram for a *Company* example.\n\nFigure 3.13: Code execution from Figure 3.11.\n\nFigure 3.14: Object diagram after the execution of the program in Figure 3.13.\nOn the first stage of our approach we need to generate a set of OCL constraints at M1 level for the composition property using as input the class diagram in Figure 3.12. These constraints will be used by the program testing module. The constraints are defined as a post-condition of the method that implements the lifetime property in the owner class. For this example, we generate the following constraint:\n\n```ocl\nclass Company:\n destroy():\n post: self.div->forall(x | Client.allInstances(y | y.divisions->excludes(x))}]\n```\n\nIn the code in Figure 3.11, the method we are interested on is `destroy()`. As we mentioned in previous sections, the lifetime property requires that if a composite is removed its parts should also be removed, i.e. when an owner object does not exist; then neither does its part objects. An owner object and its part objects are said to “not exist” when all external links to the objects are removed, making them unreachable by any other object. Figure 3.15 shows an example of the destruction of an owner object and its part object.\n\n\n\nFigure 3.15: The destruction of an owner and part objects.\n\nTo check the correctness of the method `destroy()`, we need to execute it on all possible test inputs up to a bounded size. Each test input is an instance (object diagram) of the class diagram in Figure 3.12 and can be generated by executing a set of instructions similar to the ones in Figure 3.13. In Figure 3.16 we have three object diagrams where `cmpy1` is an instance of class `Company`, `div1` is an instance of class `Division`, `cli1` is an instance of class `Client`, and `univ1` and `univ2` are instances of class `University`. Also, the diagrams above and below the arrows denote the pre-states and\npost-states before and after executing the method \\textit{destroy()}.\n\nAfter the execution of the method \\textit{destroy()}, we validate the lifetime property by applying the previously generated OCL constraint to the resulting object diagram. The constraint is satisfied if all the links to the owned objects are removed. In this example, in the post-state of the object diagram \\textit{o1} in Figure 3.16, the link between \\textit{div1} and \\textit{cli1} was removed. Therefore, the lifetime property is satisfied.\n\nFigure 3.16: Object diagrams before and after calling \\textit{destroy()}. \n\nDuring the execution of the method \\textit{destroy()}, we monitor its execution to detect the fields read and use this information to prune the test input space. Figure 3.16 shows a set of three object diagrams before the execution of method \\textit{destroy()} (pre-state) and after the execution of method \\textit{destroy()} (post-state); the highlighted links correspond to the fields we detect being read during its execution. After validating the lifetime property, we can prune similar object diagrams where the fields read have the same values. The logic behind this decision is based on the fact that fields that are not being read by the method \\textit{destroy()} do not affect its execution. Therefore, as\nlong as the fields read have the same values, the result for the lifetime property will be the same. In this example, the object diagrams \\( o1 \\) and \\( o2 \\) are considered similar, unlike the object diagram \\( o3 \\) where the value of one of the fields read is different.\n\nBased on the implementation of the method \\( \\text{destroy()} \\) in Figure 3.11, we can detect that only the links between instances of class \\( \\text{Company} \\) and class \\( \\text{Division} \\) are relevant to the lifetime property. Therefore, it is sufficient to check every possible object diagram with different number of links between instances of class \\( \\text{Company} \\) and class \\( \\text{Division} \\). This approach greatly reduces the size of the test input space. Without pruning similar object diagrams, the number of object diagrams checked is exponential in the bounds of the number of objects instantiated for each of the classes in Figure 3.12.\n\n### 3.1.4.2 Program Testing Implementation\n\nAs mentioned in the previous section, to effectively determine the absence of UML association properties violations in a program, we use the bounded exhaustive testing technique. Following this technique, we generate all possible test inputs whose size is within a certain bound, and for this, it must be provided with a domain value for each of the variables.\n\nA domain value indicates the maximum number of objects instantiated for each of the classes in the test case. A single combination of these objects represents a test input or object diagram, and all possible combinations consist of a large number of test inputs that we call test input space. Among all possible test inputs, some are not valid. To generate only valid test inputs, we consider the multiplicity and navigability information from the class diagram (when testing properties other than multiplicity and navigability).\n\nWhen testing composition, our tool calls the method implementing the lifetime property on one of the valid test inputs. After its execution, we check the lifetime\n1 for each composition property in the class diagram\n2 od = use a solver to generate a valid test input\n3 while (od does exist)\n4 call method under test on od (i.e., destroy)\n5 apply OCL constraint on post-state\n6 use the solver to prune similar test inputs\n7 od = use solver to generate the next valid test input\n\nListing III.1: Algorithm to check UML composition property.\n\nproperty using the generated OCL constraints and prune away similar test inputs from the test input space. We repeat the process until there are no more valid test inputs.\n\n3.1.4.3 Test Input Space Representation\n\nTo generate the test input space we use a finitization to specify the maximum number of objects for each for the classes in the test case. For the composition property, the finitization includes values for the owner, owned, and third-party classes. For example, for the finitization (2,2,1) for the class diagram in Figure 3.12, the test input space includes all object diagrams with up to two instances of classes Company, up to two instances of class Division, and one instance of class Client. Using this finitization, our tool generates the domain values for each of the fields needed to create an object diagram. Table 3.1 shows the fields and domain values for finitization (2,2,1).\n\nTo generate a test input, our tool uses the SAT solver SAT4J [44]. SAT4J uses\na vector structure where each element is a Boolean value. Therefore, we need to translate the finitization information to a vector form. For finitization (2,2,1) shown in Table 3.1, our tool generates a twelve bit vector. The first two bits, (N0 and N1) represent whether objects \\textit{div1} and \\textit{div2} are referenced by \\textit{cmpy1}. If N0 is true, it means that \\textit{div1} is referenced by \\textit{cmpy1}, i.e., object \\textit{cmpy1} has a link to object \\textit{div1}, and a false value means that there is no reference. The bits N2 and N3 represent whether objects \\textit{div1} and \\textit{div2} are referenced by \\textit{cmpy2}. Bits N4 and N5 represent whether objects \\textit{cmpy1} and \\textit{cmpy2} are referenced by \\textit{div1}. The bits N6 and N7 denote whether objects \\textit{cmpy1} and \\textit{cmpy2} are referenced by \\textit{div2}. Bits N8 and N9 represent whether object \\textit{cli1} is referenced by \\textit{div1} and \\textit{div2} respectively. And finally, bits N10 and N11 specify whether objects \\textit{div1} and \\textit{div2} are referenced by \\textit{cli1}. Also, since the multiplicity is greater than 0, our tool includes an instance of class \\textit{University, univ1}, adding bits N12 that specifies whether object \\textit{cli1} has a reference to \\textit{univ1}, and N13 to specify whether \\textit{univ1} has a reference to \\textit{cli1}.\n\n\\begin{figure}[h]\n\\centering\n\\includegraphics[width=0.5\\textwidth]{object-diagram.png}\n\\caption{An object diagram.}\n\\end{figure}\n\nThe following is the vector for the object diagram in Figure 3.17. This vector is then converted to an object diagram that is used as a test input.\n\n\\begin{verbatim}\nT T F F T F T F T T T T T T\n\\end{verbatim}\n\n3.1.4.4 Pruning Invalid Test Inputs\n\nTo generate a valid test input, SAT4J needs a set of formulas that specify valid assignments to the vector structure. These formulas reflect the different domain values in our test case, as well as the constraints obtained from the class diagram. Also,\nwe dynamically apply new formulas to the solver after the execution of the method under test to prune away similar test inputs.\n\nWe consider two constraints from a class diagram: multiplicity and navigability. The multiplicity constraint specifies a lower and upper bound on the number of instances of a class on an association end. In the class diagram in Figure 3.12, the multiplicity for the class Company’s end indicates that an instance of class Division can have a reference to one and only one instance of class Company. If an instance of class Division has a reference to more than one instance of class Company, the object diagram is considered invalid. The second constraint, navigability, specifies whether an object has a reference to another object. The navigability is related to the type of association between two classes in a class diagram. If the association is bidirectional, instances of the classes related to that association must reference each other. If it is unidirectional, only one object will reference the second object. In the class diagram in Figure 3.12, the association between classes Division and Client is bidirectional. This means that an instance of class Division must reference an instance of class Client and that same instance of class Client must reference the same instance of class Division.\n\nTo prune invalid test inputs with respect to the multiplicity constraint, we apply a set of formulas. For example, considering the multiplicity constraint for the class Company’s end in Figure 3.12, the following is an invalid vector:\n\n```\n- - - T T - - - - - - - -\n```\n\nIn this vector, the assignment to bits N4 and N5 is true. This means that object div1 has references to objects cmpy1 and cmpy2, which violates the multiplicity constraint. We use the formula \\( \\neg (N4 \\land N5) \\) to eliminate all the vectors where the multiplicity constraint is not satisfied by the object div1. With this single formula, we eliminate 212 invalid object diagrams. A similar formula is used to eliminate invalid vectors where the multiplicity constraint is not satisfied by the object div2.\nAlso, to eliminate invalid vectors with respect to the navigability constraint, we use a similar approach. For example, considering the bidirectional association between classes *Division* and *Client* in Figure 3.12, the following is an invalid vector:\n\n```\n- - - - - - T - T - -\n```\n\nIn this vector, the assignment to bits N8 and N10 is true. This assignment means that object *div2* has a reference to object *cli1* while object *cli1* has a reference to object *div1*. The bidirectional constraint is not satisfied. We can use the formula \\( N8 \\iff N11 \\) to enforce the navigability for the association between classes *Client* and *Division*.\n\n### 3.1.4.5 Monitoring the Method under Test\n\nAfter pruning invalid test inputs, we further prune the test input space by using runtime information. Specifically, we use two techniques: the detection of do not care fields and the pruning of isomorphic test inputs (object diagrams).\n\n### 3.1.4.6 Do Not Care Fields\n\nDuring the execution of the method under test, we monitor the fields derived from the class diagram that are being read in order to identify do not care fields. A field is considered a “do not care” field if it is not read during the method’s execution. The fields are called do not care fields because they are not relevant to the execution of the method, i.e. no matter what values the do not care fields have, the result of the lifetime property after the execution of the method is the same.\n\nTo illustrate how we use the do not care fields to prune the test input space, let’s consider the following example. After calling the method `destroy()` in Figure 3.11 on the object diagram in Figure 3.17, we detect that only three fields are read: field `div` in class *Company*, field `clients` in class *Division*, and field `divisions` in class *Client*. \nIn our vector representation, these fields correspond to the bits N0, N1, N4, N6, N8, N9, N10, N11, N12, and N13. Among those bits, N12 and N13 are identified as do not care fields. The following vector shows the bits corresponding to the do not care fields marked with a dash.\n\n| T | T | F | F | T | F | F | T | T | T | T | - | - |\n\nAfter identifying the do not care fields, we prune the test input space by applying a new formula to SAT4J. This formula eliminates the set of vectors that only differ on the values for the do not care fields. For the previous example, the formula \\( \\neg(N0 \\land N1 \\land N2 \\land N3 \\land N4 \\land N5 \\land N6 \\land N7 \\land N8 \\land N9 \\land N10 \\land N11) \\) is added to the solver.\n\n### 3.1.4.7 Pruning Isomorphic Object Diagrams\n\nAfter eliminating similar states by identifying do not care fields, we further reduce the test input space by pruning isomorphic object diagrams (test inputs). Two object diagrams are said to be isomorphic when they are equivalent in terms of the number of objects and number of links in the diagram. In other words, the number of objects of each class is the same, as well as the number of links between them. As an example, the object diagrams in Figure 3.18 are equivalent, differing only by the name of the object of type Division, div1 and div2.\n\nExecuting the method under test and checking the lifetime property in two isomorphic test inputs generates the same result. For example, considering the method destroy() in Figure 3.11, its execution is only affected by the number of objects in the fields corresponding to the associations in the class diagram, namely div, clients, and divisions. As long as the number of objects is the same, the execution of the method will be the same.\n\nTo prune the isomorphic test inputs, we generate the formula \\( \\neg(x.div = y \\land y.clients = cli1) \\) where \\( x \\in \\{cmpy1, cmpy2\\} \\) and \\( y \\in \\{div1, div2\\} \\). This formula\nprunes away three isomorphic object diagrams. Pruning isomorphic inputs states can greatly reduce the size of the test input space without reducing the fault detection accuracy of our approach.\n\n### 3.1.5 Small Scope Hypothesis\n\nThe small scope hypothesis is a key aspect to confirm the effectiveness of our approach, and as such, it must be verified. To do this, we used the mutation testing technique. In order to perform the mutation testing we generated a set of mutants. A mutant can be generated by applying a mutation operator to the program under test. In our case, we concentrated in mutations to the `destroy()` method and accessor methods. The operations we used to generate the mutants are:\n\n- Java operator replacement, e.g., replacing “==” by “!=”.\n- Change of variable/method calls, e.g., calling a different method.\n- Change of variables value by adding additional assignments.\n\nIn mutation testing, it is important to generate valid mutants, i.e., to generate mutants that can be compiled. Therefore, when generating mutants by changing\nvariable/method calls, the variables used for the mutation were a subset of the original variable.\n\nWe found that in most cases, a finitization as small as (1,1,1) that represents up to one owner object, up to one part object, and up to one third party object, was enough to expose the faults introduced by the mutations. The reason for this is that the UML2 implementations heavily use collection types where the behavior of a program with a collection of one element is no different from the behavior when the collection contains many elements. There were two exceptions, however, when a higher number of objects was needed. The first case occurred when checking the composition relationship between the classes Connector and ConnectorEnd in the UML metamodel implementation. In this composition relationship, the multiplicity on the ConnectorEnd enforces the creation of two objects of ConnectorEnd with a link to Connector. In this case, the finitization needed to expose this fault was (1,2,2). The second case occurred when we mutated the method getOwnedEnd() in class Association. When an Association object has two Property objects, the fault is not exposed, but in an Association object with three Property objects the fault is exposed. The reason is that an Association object owns the Property objects only when it has three or more. If it only has two, the objects are not owned by the Association object. For this case, the finitization (1,3,3) was needed.\n\n3.2 Bounded Exhaustive Testing Limitations\n\n3.2.1 Effectiveness\n\nOne of the drawbacks of exhaustive test case generation is that it does not guaranty a full exploration of the possible execution paths in the method under test, which may result in missing test cases that could expose a problem in the implementation. As previously explained, the small scope hypothesis can give us a high degree of\nconfidence that a problem will be uncovered, but it cannot be guarantee the method is correct in terms of a particular OCL constraint. This uncertainty may not be acceptable in some scenarios. When working with bounded exhaustive testing, there is always a risk of not selecting a bound large enough. As an example, Figure 3.19 shows a scenario where a particular behavior can only be exposed by an input large enough, making the bound selection an important factor to correctly check all possible behaviors in the method.\n\n```java\npublic int intPowerOfTwo(int a, int b){\n if(a>30){\n throw new RuntimeException(\"Result out of range.\");\n }\n int result = 2;\n for(int i=1; i<a; i++){\n result *= 2;\n }\n return result;\n}\n```\n\nFigure 3.19: Bounded exhaustive testing limitations.\n\n### 3.2.2 Efficiency\n\nIn terms of efficiency, compared to an approach that leverages information about previous executions when generating test cases, e.g., test case generation based on branch coverage, bounded exhaustive test case generation is more inefficient. The analysis of do not care fields in our approach can greatly improve on simple exhaustive test case generation, but it still does not completely rule out the generation of extraneous test cases that produce the result. Consider again the method in Figure 3.19. Using bounded exhaustive test case generation with do not care fields, with a large enough bound, e.g., \\( a, b \\leq 35 \\) we can correctly explore all possible execution paths in the method while reducing the number of test cases generated by detecting \\( b \\) as a do not care field. However, it would still generate a number of extraneous test cases, namely, all test cases where \\( a \\leq 30 \\) will result in the exact same execution, resulting in a loss of efficiency. Without leveraging previous execution information, such as path condition for branch coverage, it is hard to detect such scenarios to\nimprove the efficiency.\n\nIn the following chapter we introduce an improvement that uses a testing validation technique combining coverage criteria and dynamic symbolic execution. Our approach reduces the number of test cases making it more efficient and it guaranties the correctness of a method in terms of a specific OCL constraint.\nCHAPTER IV\n\nPATH CONDITION ANALYSIS\n\n4.1 Overview\n\nTo illustrate our consistency checking approach with path condition analysis, we will use as an example the class diagram shown in Figure 4.1 (a), an excerpt from the Royal and Loyal system [12]. The example consists of the classes ServiceLevel, Membership, and LoyaltyAccount, with a few attributes and associations each. The class diagram also includes an OCL post-condition attached to the method earn() in class LoyaltyAccount. We will refer to earn() as the method under test. Based on this example, the objective of our approach is to determine if the OCL specification for the method earn() is satisfied by the method’s Java implementation. Also, Figure 4.1 (b) shows a partial skeletal Java Program that was automatically generated by the forward engineering tool Rational Software Architect (RSA) [14].\n\nThe automatic code generation by a forward engineering tool can be illustrated by a translation schema that includes a set of rules that map elements in the model to elements in the target language. In this example, the model is the class diagram shown in Figure 4.1 (a) and the target language is Java. For instance, based on RSA’s translation schema, shown in Table 2.1, a property in the UML class diagram is mapped to a private class field with a setter and getter method in the Java program. An association in the UML class diagram is treated as a property and it is also\ntranslated to a field in the corresponding class. Most translation schemas follow a similar approach when translating UML associations, since most target languages do not directly support the extra semantics associated with them, such as multiplicity.\n\n\n\n\n\nFigure 4.1: Forward engineering feature supported by RSA.\n\nThe class diagram, Java skeletal program, shown in Figure 4.1, and the developer’s implementation for the method `earn()`, shown in Figure 4.2, serve as the input to our approach. To determine if the OCL specification for the method `earn()` is satisfied by the method’s Java implementation, as a first step we automatically generate a Java Boolean post-method from the OCL post-condition. The OCL post-condition and the resulting Java Boolean method are shown in Figure 4.3 (a) and Figure 4.3 (b) respectively. Based on the relationship between the OCL post-condition and\n```java\npublic void earn(Integer i){\n points += i;\n if(points > 100){\n membership.getCurrentLevel().setName(\"Gold\");\n }else{\n if(points >= 0){\n membership.getCurrentLevel().setName(\"Silver\");\n }else{\n membership.getCurrentLevel().setName(\"Inactive\");\n }\n }\n}\n```\n\nFigure 4.2: Developer’s `earn()` implementation.\n\n```java\ncontext LoyaltyAccount::earn(i:Integer)\npost: let level:String = membership.currentLevel.name in\n points > 200 implies level = \"Platinum\" and\n points > 100 and points <= 200 implies level = \"Gold\" and\n points >= 0 and points <= 100 implies level = \"Silver\" and\n points < 0 implies level = \"Inactive\"\n(a)\n```\n\n```java\npublic boolean post_earn(int i){\n String level = this.getMembership().getCurrentLevel().getName();\n boolean r0 = false;\n if (((this.getPoints() > 200) || level == \"Platinum\")\n && ((this.getPoints() > 100) && this.getPoints() <= 200)\n && level == \"Gold\")\n && ((this.getPoints()) >= 0 && this.getPoints() <= 100)\n && level == \"Silver\")\n && ((this.getPoints()) < 0 || level == \"Inactive\") {\n r0 = true;\n }\n return r0;\n(b)\n```\n\nFigure 4.3: OCL post-condition to Java translation.\n\nthe generated Java Boolean method, the problem of finding if the method `earn()` satisfies its OCL post-condition can be reduced to testing if the equivalent Boolean post method always returns true after the execution of the method under test.\n\nAfter the translation, we generate an initial minimal test case value for the method `earn()` using the translation schema to match elements between the class diagram and its implementation. Each test case value must correspond to a valid object diagram, i.e., the object diagram must be a valid instance of the class diagram shown in Figure 4.1 (a). To generate a minimal test case, i.e., a test case with the smallest number of objects needed to execute the method under test, we start by instantiating the class where the method resides, in this example `LoyaltyAccount`. Next, we parse the class diagram to find required associations in terms of multiplicity and navigability. As an example, looking at the relationship between `LoyaltyAccount` with `Membership`, the multiplicity of 1 tells us that we need exactly one instance of `Membership`. The code in Figure 4.4 (b) show the statements needed to generate the initial minimal test\nvalue. These statements are specific to the translation schema introduced earlier.\n\n```java\npublic void test_case(){\n LoyaltyAccount lc = new LoyaltyAccount();\n Membership ms = new Membership();\n ServiceLevel sc = new ServiceLevel();\n lc.setMembership(ms);\n ms.setLoyaltyAccount(lc);\n ms.setServiceLevel(sc);\n sc.setMembership(ms);\n int i = 0;\n lc.earn(i);\n}\n```\n\nFigure 4.4: Initial test case value.\n\nThe next step consists on executing the method under test, `earn()`, at the same time we perform symbolic execution to collect the path condition `pc`. Next, we execute the Java Boolean post method, `postearn()`, while also performing symbolic execution to collect the path condition `pc_post`. For the purposes of consistency checking, during symbolic execution, we only track all object references, class fields, and method parameters derived from the class diagram. The relationship of the resulting path conditions is then analyzed to guide the test case value generation. Figure 4.5 and 4.7 shows the execution trace and resulting path conditions after the execution of the initial test case and Java Boolean post method. Note that the path condition of the method under test and the post method are both defined in terms of the initial test input values.\n\nIf the method `postearn()` returns false, a software fault has been found and it can be reported. Otherwise, we determine with the use of a SAT solver whether $pc \\implies pc_post$ is a tautology. If the implication relationship is a tautology, then all test case values satisfying `pc` also satisfy `pc_post` and follow the same execution path in `earn()` and `postearn()` as in the previous execution. In this scenario, the set of test cases satisfying `pc` is a subset of test cases satisfying `pc_post` as shown in Figure 4.6.\n\nBased on the previous observation, we need to explore a different execution path on `earn()`. To do so, we use a SAT solver to find a new test case value satisfying\nFigure 4.5: Trace I execution, $earn(0)$.\n\nFigure 4.6: $pc$ and $pc_{post}$ relationship after first execution.\n\nPath Condition\n\n$pc : points_0 + i_0 \\leq 100 \\land points_0 + i_0 \\geq 0$\n\nPost Method Post Condition\n\n$pc_{post} : points_0 + i_0 \\leq 200 \\land points_0 + i_0 \\leq 100 \\land points_0 + i_0 < 0 \\land name_0 = 'Silver'$\n\nFigure 4.7: $pc$ and $pc_{post}$ path conditions after first execution.\n\\((\\text{points}_0 + i_0 \\leq 100) \\land \\neg(\\text{points}_0 + i_0 \\geq 0)\\), to enforce a different execution path. Our approach uses a last-input-first-output stack to store the path conditions collected during execution and follows a back-tracking approach to explore different execution paths by flipping branches. In this example, the SAT solver returns an assignment of 0 for \\(\\text{points}_0\\), and -1 for \\(i_0\\). With this information, we generate a new object diagram as a test case with the values returned by the SAT solver, and execute the method under test, i.e., \\(\\text{earn}(-1)\\), and post method. Figure 4.8 shows the resulting path conditions.\n\n**Path Condition**\n\\[\n\\text{pc} : \\text{points}_0 + i_0 \\leq 100 \\land \\text{points}_0 + i_0 < 0\n\\]\n\n**Post Method Post Condition**\n\\[\n\\text{pc}_{\\text{post}} : \\text{points}_0 + i_0 \\leq 200 \\land \\text{points}_0 + i_0 \\leq 100 \\land \\text{points}_0 + i_0 < 0 \\land \\text{name}_0 = '\\text{Inactive}'\n\\]\n\nFigure 4.8: \\(\\text{pc}\\) and \\(\\text{pc}_{\\text{post}}\\) path conditions after second execution.\n\nOnce again \\(\\text{post}_{\\text{earn}}()\\) returns true and \\(\\text{pc} \\implies \\text{pc}_{\\text{post}}\\) is found to be a tautology by the SAT solver. Using a backtracking approach, the SAT solver is used to find an assignment that satisfies \\(\\neg(\\text{points}_0 + i_0 \\leq 100)\\). The resulting assignment is \\(\\text{points}_0 = 0\\), and \\(i_0 = 150\\). Using these assignments, a third test case value is generated, and the methods are once again executed. Figure 4.9 shows the resulting path conditions.\n\n**Path Condition**\n\\[\n\\text{pc} : \\text{points}_0 + i_0 > 100\n\\]\n\n**Post Method Post Condition**\n\\[\n\\text{pc}_{\\text{post}} : \\text{points}_0 + i_0 \\leq 200 \\land \\text{points}_0 + i_0 > 100 \\land \\text{name}_0 = '\\text{Gold}'\n\\]\n\nFigure 4.9: \\(\\text{pc}\\) and \\(\\text{pc}_{\\text{post}}\\) path conditions after third execution.\n\nAgain, \\(\\text{post}_{\\text{earn}}()\\) returns true, but the SAT solver determines that \\(\\text{pc} \\implies \\text{pc}_{\\text{post}}\\) is not a tautology. This means that some test values that satisfy \\(\\text{pc}\\), following the same\nexecution path on \\( earn() \\), does not follow the same execution path on \\( post_{earn}() \\). In this scenario, the set of test cases satisfying \\( pc \\) is not a subset of test cases satisfying \\( pc_{post} \\) as shown is Figure 4.10. Since a different execution path on \\( post_{earn}() \\) could return false, we attempt to find a test case value which alters the execution path on \\( post_{earn}() \\) with the formula \\( pc \\land \\neg pc_{post} \\), using a backtracking approach on \\( pc_{post} \\). In this example, the backtracking technique on \\( pc_{post} \\) will generate three test cases. In the first test case, the sub-expression \\( (name_0 = \\text{\"Gold\"}) \\) is negated. As a result, the following formula is sent to the SAT solver: \\( points_0 + i_0 > 100 \\land points_0 + i_0 \\leq 200 \\land points_0 + i_0 > 100 \\land \\neg (name_0 = \\text{\"Gold\"}) \\). In this case, the value of \\( points_0 + i_0 \\) will remain > 100 and \\( <= 200 \\), which will result in the same execution as the one on the third execution. Regardless of the initial value of \\( name_0 \\), its value is overridden by method \\( earn() \\). As a result, we once again find that \\( pc \\implies pc_{post} \\) is not a tautology and continue with the backtracking of \\( pc_{post} \\). In the second case, the sub-expression \\( points_0 + i_0 <= 200 \\) is negated, resulting in the following assignment: \\( points_0 = 0, i_0 = 220 \\). Note that when sending a formula, it is up to the SAT solver how the values are assigned. In this example, an equivalent assignment could be: \\( points_0 = 220, i_0 = 0 \\).\n\n\n\nThis time, after the execution of the method under test, we find that \\( post_{earn}() \\) returns false, which means the method \\( earn() \\) does not satisfy the OCL post-condition defined in the class diagram. This means a fault has been found.\n4.2 Algorithm\n\nOur approach uses as input a UML class diagram, with at least one method (method under test) with an OCL post-condition, and a Java implementation of the diagram. From the diagram, the OCL constraint is parsed and automatically translated to a Boolean Java method (post method). Next, the method under test and post method are instrumented to support dynamic symbolic execution. If the class diagram contains multiple methods with OCL post-conditions, each method is tested individually using the same procedure. Following the instrumentation, a minimal initial test case value is generated. Finally, a minimal test case that includes the smallest number of objects needed to execute the method under test is generated. The previous initialization steps are shown in lines 3-10 in Listing IV.1.\n\nHaving the initial test case value, the method under test and post methods are executed while concurrently performing symbolic execution to collect each method’s path condition (lines 11-14 in Listing IV.1). After the execution of the methods, if the post method returns false, the error is reported, otherwise, the path conditions are evaluated and a different test case value is generated to follow a different execution path from the previously observed (lines 15-30 in Listing IV.1). The process is repeated until an error is found or branch coverage has been achieved on the method under test. More details about the initialization, methods execution, and results evaluation are given in the following sub-sections.\n\n4.2.1 Initialization\n\nThe initial step consists on parsing the class diagram to extract available OCL post-conditions. To parse the diagram, we use the MDT EMF framework [6], and we support the EMF Ecore model format. Other model formats can be translated to the Ecore model format using a modeling tool such as Eclipse. After parsing the diagram, the OCL post-conditions are translated to an equivalent Java Boolean\ninput: class diagram CD with OCL, and Java program P\nmethods = select all methods with attached OCL post-conditions\nfor each m in methods\n m_post = generate_post_method(m, CD)\n add m_post to class of m\ninstrument program P to collect the path condition during execution\nfor each m in methods\n init_values = null\ntest_values = generate_test_values(m, cd, init_values)\nwhile there exists a new test_values\n pc = []; heap = []; pc_post = []\n exec_symbolic(m, test_values, heap, pc)\n is_valid = exec_symbolic(m_post, test_values, heap, pc_post)\n if is_valid is false\n report error and return\n else\n result = use SAT solver to check if pc ⇒ pc\\text{post} is tautology\n if result is true\n do\n init_values = sat_find_next_init(¬pc)\n if init_values != null\n test_values = generate_test_values(m, cd, init_values)\n while test_values == null & init_values != null\n else\n do\n init_values = sat_find_next_init(pc ∧ ¬pc\\text{post})\n if init_values != null\n test_values = generate_test_values(m, cd, init_values)\n while test_values == null & init_values != null\nListing IV.1: Main algorithm.\n\nmethod. The translation is based on the OMG OCL 2.31 specification [8] and uses the OCL translation schema introduces my Warmer et al. [12]. The translation process begins by parsing the OCL post-condition using the MDT OCL project [45]. The parsing generates an abstract syntax tree (AST) of the expression. During the parsing process, we construct an equivalent abstract syntax tree that trims some information from the previous AST for easy access and translation. In the generated tree, each node implements a translate method that is recursively called from the root node to generate the corresponding Java code.\n\nTo illustrate the translation process, we will use the OCL expression shown in Figure 4.1 (a) as an example. The generated AST is shown in Figure 4.12 where the root element corresponds to the whole IF expression and its child nodes represent the enclosing sub-expressions. For instance, the root node in Figure 4.12 shows an IF expression that is composed of three different sub-expressions, namely, a condition.\nexpression, a *then* expression, and an *else* expression, which are the child nodes of the IF Exp root node. After the tree is generated, using the Visitor pattern we visit the nodes and recursively call the translate method on each. The translate method generates a Java code fragment for each node. In non-leaf nodes, the method further traverses the child node(s) and generates its corresponding code fragment using the result of its child nodes, and leaf nodes only generate a code fragment that is used by the corresponding parent. Finally, a root node collects all the generated code fragments and produces the final complete Java code for the post method. The code in Figure 4.11 (b) shows the result of the translation and Figure 4.13 shows the translation templates used in this example.\n\n```java\ncontext Node:orderChildren():Boolean\npost: if self.lefth <> null and self.right <> null then\n ... \nelse true endif\n(a) OCL Constraint\n(b) Generated Java Code\n```\n\nFigure 4.11: OCL to Java translation example.\n\n### 4.2.2 Test Case Generation\n\nUsing the class diagram in Figure 4.14 as an example, where *earn()* is the method under test, the minimum test case generation starts by instantiating the class where the method under test resides. In this example, the class *LoyaltyAccount* is instantiated. Note that the class is only instantiated if the method under test is an instance method, otherwise the method under test would not require an instance to be executed, as it is the case with static methods Java. After the instantiation of class *LoyaltyAccount*, we need to recursively check for required associations in terms of multiplicity and navigability. An association is said to be required if the multiplicity’s\nFig. 4.12: Partial generated AST from OCL in 4.11 (a)\n\nIF Expression Template (if exp then exp else exp endif)\n```\nBoolean [result] = false;\nif([conditionExp.translate()]){\n [thenExp.translate()]\n}else{\n [elseExp.translate()]\n}\n[result] = [then/else result];\n```\n\nOCL General Expression (self <> null)\n```\nBoolean [result] = false;\nif([exp.translate()]){\n [result] = true;\n}else{\n [result] = false;\n}\n```\n\nProperty Class Expression (self.left)\n```\n[source].get[property];\n```\n\nFig. 4.13: OCL Translation Templates.\nlower bound is greater than 0. In this example, the association between LoyaltyAccount and Membership is required, since the lower bound is equal to 1. As a result, we need to instantiate class Membership and set the appropriate field on LoyaltyAccount to establish the link to Membership’s instance. Also, since the association is bi-directional, we need to set the appropriate field on class Membership to establish the link to LoyaltyAccount’s. This process is repeated recursively for each new instance added to the minimum test case value. In this example, the process is repeated on Membership’s instance, where we find a required association to class ServiceLevel. In this example, the association between LoyaltyAccount and Transaction is not found to be required since the multiplicity’s lower bound is 0, making the instantiation of Transaction class optional. For other non-association fields or parameters, we use the primitive types default values and null for reference types. The algorithm for the minimal test case generation is shown in Listing IV.2.\n\n\n\n**Figure 4.14:** Required references for minimum test case value.\n\n### 4.2.3 Methods Execution and Evaluation\n\nAfter the execution of the method under test, we initialize the SAT solver based on the observed path conditions. The initialization includes variables, and variable domains, and the sub-expressions in the path conditions. To guarantee that the SAT solver only produces valid assignments in terms of multiplicity, we construct\nalgorithm: generate_test_values\ninput: Class diagram CD with OCL, method m, and init_values\n\nself_class = class containing method m\nself_object = instantiate self_class\nset_required_references(self_class, self_object, CD)\nif init_values == null\n set parameters and fields to default values\nelse\n use init_values to initialize parameters and fields\n\nListing IV.2: Test case generation algorithm.\n\nalgorithm: set_required_references\ninput: Class diagram CD, class, and object obj\n\nfor each association assoc in class\n if assoc multiplicity > 0\n a_class = assoc reference type\n a_object = instance a_class\n set assoc field on obj to a_object\n if assoc is bi-directional\n set opposite field on a_object to obj\n set_required_references(a_class, a_object, CD)\n\nListing IV.3: Set required references algorithm.\n\nthe variable domains used by the SAT solver in such a way that no value from the\ndomain can violate the multiplicity constraints. A domain, in the context of a SAT\nsolver, denotes the set of values allowed for a particular variable when trying to find\nan assignment for a given formula. To construct the domains, we first parse the path\ncondition to select all the variables that correspond to an association end in the class\ndiagram. Next, for each variable, we get its lower bound multiplicity, \\( l \\), and upper\nbound multiplicity, \\( h \\). Based on \\( l \\) and \\( h \\), the variable domain is defined such that for\neach value in the domain, value \\( \\geq l \\) and value \\( \\leq h \\). If the upper bound is unlimited,\nwe generate up to \\( c \\) values, where \\( c \\) is a constant. To illustrate this approach, consider\nthe class diagram in 4.15 and the path condition “cmpy.dept != null”, where cmpy\nis an instance of class Company and dept refers to the association end dept in the\nassociation between Company and Department. Based on the multiplicity of “0..2”,\nwe generate a domain with the values “[0, 1, 2]”, where 0 represents the null value,\nand 1 and 2 indicate that the variable can be assigned with one or at most two\ninstances of type *Department*. For variables that do not correspond to an association end, we generate a predefined number of values depending on the variable type.\n\n\n\nFigure 4.15: Company Class Diagram.\n\nIn some instances, multiple variables corresponding to an association end may share the same domain but have different multiplicity values. As a result, the values in the domain may not be enough to enforce the multiplicity constraints for all the association ends. In this case, we add one or more sub-expressions to the formula given to the SAT solver in order to enforce all the constraints. As an example, consider two variables corresponding to the association end dept in the association between *Company* and *Department* and a variable corresponding to the association end store in the association between *Client* and *Department*, with the multiplicities 0..2 and 0..4 respectively. The domain for both variables includes the values “[0, 1, 2, 3, 4]”. In this example, the domain values only enforce the multiplicity constraint for the variable store. To enforce the multiplicity constraint for the variable dept, we add the sub-expression “*cpmy.dept* <= 2” to the formula sent to the SAT solver.\n\nAfter the initial construction of a domain, we also dynamically update the domain values, if necessary, after the execution of the method under test and post method, based on the concrete observed values during the execution and the resulting path condition. The update aims at preventing trivially unsatisfiable formulas when flipping branch conditions, due to a domain not having enough values. As an example, consider the execution of the method *earn*(0) and the resulting path con-\ndition \\( \\neg (\\$0.points + $3 > 100) \\land \\$0.points + $3 \\geq 0 \\), with the initial domain values for variable \\$3 including \\([-1, 0, 1]\\). If the branch \\( \\neg (\\$0.points + $3 > 100) \\) is flipped to cover a different execution path, i.e., \\((\\$0.points + $3 > 100)\\), and the formula is sent to the SAT solver, the formula will be trivially unsatisfiable since there is no domain value for \\$3 that can make the condition \\((\\$0.points + $3 > 100)\\) evaluate to true. To prevent this, we analyze the path condition and dynamically update the domain based on the variable’s relationship with other variables and concrete values in the path condition. In this example, we update the domain for variable \\$3 to include \\([-1, 0, 1, 100, 101]\\). A similar approach is used with non-primitive types, for example, for an association end \\( e1 \\) with a multiplicity \\( 0..* \\), we initially generate a domain with a predetermined number of values, e.g., \\( \\text{domain}(e1) = [\\text{null}, \\text{obj1}, \\text{obj2}] \\). To update the number of objects in a non-primitive type domain, CCUJ requires the size property to be part of the path condition. For example, if the following path condition is observed, \\$0.e1.size() < 4\\, \\text{, we update the domain to include four or more objects. As a result, if the branch is flipped, an assignment is possible.}\n\nAfter the execution of the methods while performing symbolic execution, we obtain the path condition for the method under test, \\( pc \\), and the path condition for the post method, \\( pc_{post} \\), and a Boolean result, returned by the post method. If the result is false, we can determine that the test case has violated the OCL post-condition and we can report an error. If the result is true, we need to analyze the generated path conditions to decide how to generate the next test case value. Using a SAT solver, we determine whether \\( pc \\implies pc_{post} \\) is a tautology. On the first possibility, if \\( pc \\implies pc_{post} \\) is a tautology, it means that all test case values satisfying \\( pc \\) also satisfy \\( pc_{post} \\). In this scenario, all the test case values that follow the same execution path on the method under test will also follow the same execution path on the post method. Since the result of the post method was true, we are interested on exploring a different execution path on the method under test to see if we can obtain a different\nresult on the post method. To do this, we use the SAT solver to find a new assignment by negating a sub condition of $pc$ using a backtracking technique to eventually achieve branch coverage. On the second possibility, if $pc \\implies pc_{post}$ is not a tautology, it means that there is a test case value satisfying $pc$ that does not satisfy $pc_{post}$. In other words, there is a test case value that would follow the same execution path on the method under test but would follow a different execution path on the post method. In this case, we are interested in finding such a test case, since a different execution path on post method could possibly return a different post-condition result. To do so, we use the SAT solver to find an assignment for the formula $pc \\land \\neg pc_{post}$. In both cases, whether $pc \\implies pc_{post}$ is a tautology or not, after finding the assignment, the process is repeated until there are no more branches to explore on the method under test or an error is detected.\n\n4.2.4 Multiplicity and Navigability as OCL Pre-Conditions\n\nAs introduced earlier, each test case value must correspond to a valid object diagram, i.e., the object diagram must be a valid instance of the class diagram in terms of the multiplicity and navigability constraints, and it must be a minimal test case, i.e., it should consist on the minimum number of objects needed to execute the method under test, starting with an instance of the class where the method is defined. A minimal valid test case can be specified with set of OCL expressions as pre-conditions for the method under test, both in terms of multiplicity and navigability.\n\nAs an example, the multiplicity constraint as a pre-condition, based on the diagram in Figure 4.1 (a) can be defined as shown in Listing IV.4. The constraint guarantees the method will be executed in a valid object diagram in terms of the multiplicity. In this example, the constraints specifies the test case will include an instance of Membership, and an instance of ServiceLevel, and that both instances will be set using the respective fields, membership and serviceLevel. In a similar way, the navigability\ncontext LoyaltyAccount::earn(int i)\npre: self.membership != null and\n self.membership.serviceLevel != null\n\nListing IV.4: Multiplicity as pre-condition.\n\nclass LoyaltyAccount::earn(int i)\npre: self.membership.account == self and\n self.membership.serviceLevel.membership == self.membership\n\nListing IV.5: Navigability as pre-condition.\n\nconstraint ensures the links between instances is set according to the ones defined in the diagram. The *navigability* constraint is shown in Listing IV.5. If no OCL pre-conditions are defined for the method, our approach implicitly uses the *multiplicity* and *navigability* constraints as the method’s *pre-conditions*.\n\n4.2.5 Black Box Methods\n\nWhen executing the method under test and post method, there may be calls to external methods where dynamic symbolic execution is not possible, i.e., we are unable to collect the path condition of their execution. Typically, this is related to cases where instrumentation is not possible due to licensing restrictions, or because the binary files are not directly accessible. We call these type of methods, *black box methods*. In our current implementation, we treat the Java Collection API and the EMF API as *black box* methods. We do not instrument these APIs since they are not part of the design class diagram and doing so would complicate the dynamic symbolic execution since many auxiliary fields introduced by the EMF forward engineering feature would have to be tracked during the execution. In order for our approach to work with these type of methods, we use a set of rules, based on the method’s specification, to update the path condition and symbolic memory when a call to an EMF method or Java collection method is detected. In the following subsections we explain the type of scenarios where it is safe to ignore the *black box* path conditions.\nAlso, we explain how we use approximate symbolic execution to update the symbolic memory according to the semantics of the black box methods. In particular, we support approximate symbolic execution for the Java collection methods, i.e., the List implementation ArrayList, and for the EMF methods eContents(), and eContainer().\n\n4.2.5.1 Ignoring Path Conditions of Black Box Methods\n\nIn general, the scenario where the path condition of a black box method, \\( bb_{pc} \\), can be safely ignored, is when the set of test cases satisfying the path condition of the method under test, \\( wb_{pc} \\), is a subset of the path condition of the black box method, i.e., \\( wb_{pc} \\Rightarrow bb_{pc} \\) is a tautology, as shown in Figure 4.16. In this scenario, it is safe to ignore \\( bb_{pc} \\) and only consider \\( wb_{pc} \\Rightarrow pc_{post} \\), since all the test inputs satisfying \\( wb_{pc} \\) will result on the same black box method behavior. On the other hand, if the set of test cases satisfying \\( wb_{pc} \\) is not a subset of \\( bb_{pc} \\), i.e., \\( wb_{pc} \\not\\Rightarrow bb_{pc} \\) is not a tautology, as shown in Figure 4.17, the path condition of the black box method cannot be safely ignored, since a test input satisfying \\( wb_{pc} \\) could result on a different black box behavior. In relationship with \\( pc_{post} \\), there are four possible cases, two for each of the previous scenarios. The cases are shown in the following list:\n\n1. \\( wb_{pc} \\Rightarrow bb_{pc} \\) is a tautology and \\( wb_{pc} \\Rightarrow pc_{post} \\) is a tautology\n2. \\( wb_{pc} \\Rightarrow bb_{pc} \\) is a tautology and \\( wb_{pc} \\Rightarrow pc_{post} \\) is NOT a tautology\n3. \\( wb_{pc} \\Rightarrow bb_{pc} \\) is NOT a tautology and \\( wb_{pc} \\Rightarrow pc_{post} \\) is a tautology\n4. \\( wb_{pc} \\Rightarrow bb_{pc} \\) is NOT a tautology and \\( wb_{pc} \\Rightarrow pc_{post} \\) is NOT a tautology\n\nOn the first case, when \\( wb_{pc} \\Rightarrow bb_{pc} \\) is a tautology, and \\( wb_{pc} \\Rightarrow pc_{post} \\) is a tautology, our approach backtracks on \\( wb_{pc} \\). The code in Figure 4.18 shows an example of this scenario. With \\( earn_1() \\) as the test method, \\( save_1() \\) as the black box method, and \\( post_earn_1() \\) as the post condition method. For the second case,\nwhere \\( wb_{pc} \\implies bb_{pc} \\) and \\( wb_{pc} \\implies pc_{post} \\) is not a tautology, our approach backtracks on \\( pc_{post} \\) to try to find a test case that could result on the post condition returning false. This example is also shown in Figure 4.18 with \\( \\text{post}_\\text{earn}_\\text{2}() \\) as the post condition method. On the third and fourth cases, \\( wb_{pc} \\implies bb_{pc} \\) is \\textit{NOT} a tautology, and ignoring \\( bb_{pc} \\) would result in some test cases being missed. For example, with the code in Figure 4.19, and the test input \\( i = 101 \\), the implication between \\( wb_{pc} \\& x > 100 \\) and \\( pc_{post} \\) is a tautology. However, by pruning all the test cases where \\( x > 100 \\) we would miss some test cases where the behavior of the black box method would affect the post condition result, as it is the case with \\( i = 200 \\) where \\( x \\) is updated to 100, causing the post condition method to return false.\n\n\n\n\n```java\npublic int x = 0;\n\npublic String membership = \"Silver\";\n\n// W implies B\npublic void earn_1(int i) {\n x = x + i;\n if (x > 100) {\n membership = \"Gold\";\n } else {\n if (x > 50) {\n membership = \"Silver\";\n } else {\n membership = \"Inactive\";\n }\n }\n}\n\npublic void save_1(int x) {\n if (x > 100) {\n this.x = x + 10;\n } else {\n if (x > 50) {\n this.x = x + 1;\n }\n }\n}\n\n// W+B implies POST\npublic boolean post_earn_1() {\n if (x > 100) {\n return (membership == \"Gold\");\n } else {\n if (x > 50) {\n return (membership == \"Silver\");\n } else {\n return (membership == \"Inactive\");\n }\n }\n}\n\n// W+B does NOT implies POST\npublic boolean post_earn_2() {\n if (x > 200) {\n return (membership == \"Platinum\") || (membership == \"Gold\");\n } else {\n if (x > 100) {\n return (membership == \"Gold\");\n } else {\n if (x > 50) {\n return (membership == \"Silver\");\n } else {\n return (membership == \"Inactive\");\n }\n }\n }\n}\n```\n\nFigure 4.18: Safe to ignore black box path condition example.\n\n```java\npublic int x = 0;\n\npublic String membership = \"Silver\";\n\n// W does NOT implies B\npublic void earn_2(int i) {\n x = x + i;\n if (x > 100) {\n membership = \"Gold\";\n } else {\n if (x > 50) {\n membership = \"Silver\";\n } else {\n membership = \"Inactive\";\n }\n }\n}\n\npublic void save_2(int x) {\n if (x > 190) {\n this.x = x - 100;\n } else {\n if (x > 90) {\n this.x = x + 10;\n } else {\n if (x > 40) {\n this.x = x + 1;\n }\n }\n }\n}\n\n// W+B implies POST\npublic boolean post_earn_3() {\n if (x > 100) {\n return (membership == \"Gold\");\n } else {\n if (x > 50) {\n return (membership == \"Silver\");\n } else {\n return (membership == \"Inactive\");\n }\n }\n}\n\n// W+B does NOT implies POST\npublic boolean post_earn_4() {\n if (x > 180) {\n return (membership == \"Platinum\") || (membership == \"Gold\");\n } else {\n if (x > 100) {\n return (membership == \"Gold\");\n } else {\n if (x > 50) {\n return (membership == \"Silver\");\n } else {\n return (membership == \"Inactive\");\n }\n }\n }\n}\n```\n\nFigure 4.19: Not safe to ignore black box path condition example.\n4.2.5.2 Approximate Symbolic Execution of Java Collection Methods\n\n\\textit{add(}Object \\textit{obj), addAll(}Collection \\textit{c)}\n\nWhen the method \\textit{add(} \\textit{)} is executed, the symbolic memory representing the \\textit{size} property of the collection is updated to be \\textit{1} larger than its original value. As an example, consider the list \\textit{l} for the method under test shown in Figure 4.20. The symbolic value of the list and its \\textit{size} property can be represented as \\textit{l} \\textsubscript{0}, and \\textit{l} \\textsubscript{0}.\\textit{size} respectively. For the statement \\textit{l.add} \\textit{(p)} in Line 2, the symbolic value of the \\textit{size} property is updated to be \\textit{l} \\textsubscript{0}.\\textit{size} + \\textit{1}. After the symbolic memory is updated, the path condition for the statement \\textit{if} (\\textit{l.size()} > 2) \\textit{in} Line 4, with the initial list being empty, is represented as \\textit{l} \\textsubscript{0}.\\textit{size} + \\textit{1} \\textless;= \\textit{2}. Based on this path condition, our algorithm recognizes that in order to flip the branch we need to add at least \\textit{2} elements to the collection. Similar to the \\textit{add(} \\textit{)} method, when \\textit{addAll(} \\textit{)} is executed, the symbolic memory of the \\textit{size} property for the collection is updated, this time to be \\textit{size} of the original collection plus the number of objects on the collection used as a parameter. For example, the execution of \\textit{l1} \\textsubscript{0}.\\textit{addAll(l2} \\textsubscript{0}) \\textit{will update the the symbolic memory of the \\textit{size} property of \\textit{l1} \\textsubscript{0} to be \\textit{l1} \\textsubscript{0}.\\textit{size} + \\textit{l2} \\textsubscript{0}.\\textit{size}.\n\n```java\npublic boolean addExample(Person p) {\n if (p != null) {\n l.add(p);\n }\n if (l.size() > 2) {\n return true;\n } else {\n return false;\n }\n}\n```\n\nFigure 4.20: Collection black box methods \\textit{add()} and \\textit{size()} example.\n\n\\textit{size()}, \\textit{isEmpty()}\n\nWhen the method \\textit{size()} appears in a path condition, our algorithm recognizes that the observed concrete value corresponds to the number of elements in the collection. For example, for the statement \\textit{if} (\\textit{l.size()} > 2) \\textit{in} Figure 4.20, the resulting symbolic\npath condition is $l_0.size \\leq 2$, assuming the input list is empty at the moment of execution. Based on this path condition, our algorithm recognizes that we need to add at least two elements to the collection in order to flip the branch. When working with the `size()` method, we never flip a branch in such a way that the size would be given a negative value, since this is not a valid program state. As an example, the branch $l_0.size == 0$ is only flipped as $l_0.size > 0$. In a similar way, the operation `isEmpty()` is treated as an special case of the method `size()`. If the path condition contains $l_0.isEmpty() == true$, it is replaced with $l_0.size == 0$. Otherwise, if the path condition is $l_0.isEmpty() == false$, it is replace with $l_0.size > 0$. After the update, the algorithm proceeds as with the normal `size()` operation.\n\n`clear()`\n\nWhen the operation `clear()` is called, the symbolic memory for the `size` property is set to 0 using its original symbolic value. For example, using Figure 4.21 as an example, the statement `l.clear()` in Line 2 updates the symbolic memory for the `size` property as $l_0.size - l_0.size$. Subsequent calls that would affect the `size` property, such as `add()` in Line 4, will further update the symbolic value accordingly. As an example, after the execution of the statement `l.add(obj)`, the resulting symbolic memory would be $l_0.size - l_0.size + 1$, and a statement such as `if (l.size() > 0)` would result in the path condition $l_0.size - l_0.size + 1 > 0$.\n\n```java\npublic boolean clearExample(Person p) {\n if (p != null) {\n l.clear();\n l.add(p);\n if (l.size() > 0) {\n return true;\n } else {\n return false;\n }\n }\n}\n```\n\nFigure 4.21: Collection black box method `clear()` example.\ncontains(Object obj), containsAll(Collection c)\n\nUsing the example in Figure 4.22, with list l, and object p, the execution of the statement l.contains(p) is mapped to the symbolic path condition \\( p_0 \\ in \\ l_0 \\), if the result of the concrete execution is true, or \\( p_0 \\ not \\ in \\ l_0 \\) if false. Our algorithm recognizes this pattern and either adds the object p to the collection or removes it in order to flip the branch. In this example, the resulting path condition is \\( p_0 \\neq \\ null \\ and \\ p_0 \\ not \\ in \\ l_0 \\). Similar to the method contains(), the method containsAll() is mapped as list \\( l_2 \\_0 \\ in \\ l_1 \\_0 \\), with the difference that the first argument in the expression refers to a second list of objects. For these type of branches, our algorithm recognizes that in order to flip the branch, all the objects in \\( l_2 \\) must be added to the target list \\( l_1 \\), or not, depending on how the branch is being flipped.\n\n```java\npublic boolean containsExample(Person p) {\n if (p != null && l.contains(p)) {\n return true;\n } else {\n return false;\n }\n}\n```\n\nFigure 4.22: Collection black box method contains() example.\n\nindexOf(Object obj), lastIndexOf(Object obj)\n\nWith the list l and object p as input, the statement if (l.indexOf(p) == 3) is mapped as the symbolic path condition \\( p_0 \\ in \\ l_0 \\ == \\ 3 \\) if the concrete execution is true, or \\( p_0 \\ in \\ l_0 \\ != \\ 3 \\) if the result of the concrete execution is false. Our approach recognizes this as the object p being contained on the list at the specific position 3, if the concrete execution result is true, not being on the list at that position if the concrete execution result is false. To flip this branch, our algorithm adds the object exactly at position 3 by adding two other objects followed by the object p.\n\nIn a similar way to indexOf(), the method lastIndexOf() is mapped as the symbolic path condition last \\( p_0 \\ in \\ l_0 \\ == \\ 3 \\), with the addition of the keyword last, to indicate\nthat on the event of the list having the same object more than once, the index of the last occurrence must be equal to 3. For these type of method, to flip a branch, the argument object is placed at the specified position and we make sure that no occurrences of the same object are found afterwards.\n\n\\textit{equals} (\\textit{Object obj})\n\nThe method \\textit{equals} on a collection type returns \\textit{true} if the parameter object is also a list, both lists are of the same size, and all the objects in the target list are equal to the elements in the parameter list and they are at the same position, e.g., first element on \\textit{l1} is equal to the first element on \\textit{l2}, second element \\textit{l1} is equal to the second element on \\textit{l2}, etc. The execution of the statement \\textit{if (l1.equals(l2)} in the method under test, with \\textit{l1}, and \\textit{l2} as input, is mapped to the symbolic path condition \\textit{list \\textit{l1}_0 == list \\textit{l2}_0}. For these type of branches, flipping the branch requires having exactly the same set objects on both lists and at the same positions, if the required outcome is \\textit{true}.\n\n\\textit{remove} (\\textit{Object obj}), \\textit{remove} (\\textit{int index}),\n\nThe method \\textit{remove} (\\textit{Object obj}), as the opposite of method \\textit{add()}, decreases the value of the \\textit{size} property of the list, but only if the parameter object was initially contained in the list. To determine if the \\textit{size} property must be updated, during dynamic symbolic execution, we look at the concrete value returned by the operation. Only if the execution of the method returns \\textit{true}, the memory is updated. If the result is \\textit{true}, the \\textit{size} property is mapped to the symbolic value \\textit{l_0.size - 1}. In the case of the method \\textit{remove} (\\textit{int index}), the symbolic value of the \\textit{size} property is always updated. The reason is that if the index is out of range, the program would throw an exception, otherwise and element is always removed.\n4.2.5.3 Approximate Symbolic Execution of EMF Methods\n\n*eContents()*\n\nThe EMF method *eContents()* returns an unmodifiable list containing all owned elements of an object, determined by its containment features [21]. The features are set during the forward engineering process and are defined as part of the static field _OWNED_ELEMENT_ESUBSET_. To generate the list of owned elements, the method uses the feature id’s in the static field. Each feature id corresponds to each of the fields in the class containing the owned elements. For each feature id, the method calls the corresponding *get()* method to retrieve the objects. The execution of the method, which includes accessing feature id’s, and the logic determining which *get()* method to call, is part of the black box method, but the execution of the *get()* methods is not. As an example, consider the method in Figure 4.23, where _c_ is an instance of UML _Class_. Following our approach, on the second execution _c_ is not null and the statement in line 8 with the black box method is executed. The resulting path condition in this example is (_c₀ != null and _c₀.eContents().size() == 3 and _c₀.ownedAttributes == null and _c₀.ownedComments and _c₀.owned..._). As mentioned earlier, the execution of the black box method determines which *get()* method is executed but the execution of the *get()* method itself is white and it becomes part of the path condition, allowing us to see the fields access. In this example, *eContents()* executes all the *get()* methods of fields that correspond to owned elements of _Class_. Based on the path condition, we know we need to add 3 objects in one of the fields that are used to construct the list returned by *eContents()*. To determine what fields in the path condition are part of the execution of *eContents()*, we look at the static field _OWNED_ELEMENT_ESUBSET_ using Java reflection and use the feature id’s to determine the name of the fields that conform the owned set returned by *eContents()*.\nobjects and add them to the corresponding list. The reason we need to look at the static field \\textit{OWNED\\_ELEMENT\\_ESUBSET} to identify the fields is that we do not have other way of knowing which of the fields that appear in the path condition are part of the call to \\textit{eContents()} since we loose track of the execution while in the black box method.\n\n```\npublic void blackBoxExample(Class c) {\n if (c == null) {\n return;\n }\n if (c.eContents().size() > 3) {\n // ...\n }\n}\n```\n\nFigure 4.23: Example with black box EMF method \\textit{eContents()}.\n\n\\textbf{eContainer()}\n\nThe EMF method \\textit{eContainer()} returns a reference to its containing object. An object, \\(a\\), is said to be contained by an object, \\(b\\), if \\(a\\) is part of \\(b\\)’s contents, as determined by its containment features. In other words, \\(b\\) is \\(a\\)’s container if \\(b.eContents().contains(a)\\) is true. The implementation of \\textit{eContainer()} returns the value of an auxiliary field containing the reference. This field is set when the contained object is added to the a particular container. In our approach, \\textit{eContainer()} is considered a black box method. To support it, when the method is executed, we need to determine the feature id of the field in the container object in order to be able to set it. For example, for the branch \\(obj.eContainer() == \\text{null}\\), we need to identify the owner type and the field that can be used to set the containment relationship. To support this operation, we use information from the class diagram to identify the owner types where the owned element is of the same type of the object executing the \\textit{eContainer()} operation. The class diagram also gives us information about the name of the field that needs to be set to establish the containment relationship. Using this\ninformation, our approach can flip the branch `obj.eContainer() == null` by making `obj` a contained object of the owner type via the identified field.\nCHAPTER V\n\nEVALUATIONS\n\n5.1 Bounded Exhaustive Testing\n\nOur experiments include the checking of three UML composition implementations: The first one is a University example, the second one is the UML metamodel implementation v2.2.1, and the third one is the UML metamodel implementation v1.1.1. Both UML metamodel implementations are from the IBM’s Eclipse Project and are based on the Eclipse Modeling Framework (EMF). The implementation of the University example was provided by us.\n\nAlso, we manually applied the OCL constraints defined in Section 3.1.3 to code automatically generated by several forward engineering tools. We found that most tools fail or, in some cases, completely ignore the implementation of basic association properties such as navigability. Only two tools, Fujaba [46] and EMF [6], correctly implement bidirectional navigability, but, similar to the rest of the tools, they leave out the implementation for the subsetting, union, redefinition, and multiplicity properties.\n\nTo conduct our experiments, we used the Java bytecode manipulation and analysis framework ASM [47]. We instrumented the programs to monitor the fields derived from a class diagram. To this purpose, we use as an input a class diagram to gather information about the association properties to instrument the relevant fields. In the\nfollowing sections we discuss our results.\n\n5.1.1 Effectiveness\n\nWe used our approach to check two UML metamodel implementations: UML2 v1.1.1, and UML2 v2.2.1. We detected violations of the lifetime property in UML2 v1.1.1, while the shareability property was correctly implemented. UML2 v2.2.1 did not present any problems in both the lifetime and shareability property.\n\nThe fault in UML2 v1.1.1 was caused by the `destroy()` method that expects the composition relationship information to be stored in a resource object. To implement composition, the `destroy()` method iterates over every object contained in a resource looking for links to the owner object or its parts, and any link found during the check is removed. The problem with this approach is that a resource object in EMF does not provide such information. A resource object in EMF is intended to provide a mechanism to persist and reference other persisted object by serializing classes in a class diagram. When the set of objects involved in a composition relationship are not part of a resource, the `destroy()` method does not correctly enforces the lifetime property.\n\nThe fault in UML2 v1.1.1 was originally confirmed in the Eclipse UML2 forum, and was later corrected in versions such as UML2 v2.2.1. In later versions, EMF attaches an adapter to each EObject that tracks several changes, such as adding or removing references to the object. The `destroy()` method in UML v2.2.1 uses the adapters to locate and remove all links to the owner or part objects. Following this approach, UML v2.2.1 correctly enforces the lifetime property.\n\nBased on our results with the two UML composition implementations, we conclude with a high degree of confidence that UML composition was correctly implemented in v2.2.1. Also we conclude that our approach can effectively detect faults, as shown with the detection of the fault in UML2 v1.1.1.\nTable 5.1 shows the results of testing the implementation of seven forward engineering tools for the navigability, multiplicity, subsetting, union, and redefinition properties, as well as the shareability and lifetime properties for composition. Only unidirectional navigability is fully supported, bidirectional navigability is supported by two tools. Composition properties are only supported by (EMF).\n\nTable 5.1: Forward engineering tools test.\n\n<table>\n<thead>\n<tr>\n<th>Tool</th>\n<th>Unidirectional Navigability</th>\n<th>Bidirectional Navigability</th>\n<th>Link</th>\n<th>Subsetting</th>\n<th>Union</th>\n<th>Redefinition</th>\n<th>Shareability</th>\n<th>Lifetime</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Fujaba</td>\n<td>OK</td>\n<td>OK</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n</tr>\n<tr>\n<td>EMF</td>\n<td>OK</td>\n<td>OK</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>OK</td>\n<td>OK</td>\n</tr>\n<tr>\n<td>Argo UML</td>\n<td>OK</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n</tr>\n<tr>\n<td>Visual Paradigm</td>\n<td>OK</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n</tr>\n<tr>\n<td>Omondo</td>\n<td>OK</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n<td>Fail</td>\n</tr>\n<tr>\n<td>Astah*</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n</tr>\n<tr>\n<td>Altova*</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n<td>-</td>\n</tr>\n</tbody>\n</table>\n\n* Unable to test, the tools do not provide getter/setter implementations\n\n5.1.2 Efficiency\n\nTo show our tools efficiency in the generation of the test input space, we compare it with Korat, a tool for test inputs generation for Java programs [48]. Korat requires an invariant method, called repOK() to generate all the test inputs. In our case, for the test of composition the invariant method should be based on the two constraints, namely the multiplicity and navigability constraints. As an example, in Figure 3.12, repOK() for class Company checks the multiplicity and navigability of class Division’s end. For class Division, repOK() checks the multiplicity and navigability of the ends for classes Company and Client. For class Client, repOK() checks the ends form classes Division and University. And finally, repOK() for class University checks the multiplicity and navigability of class Client’s end.\n\nSince Korat uses the all-field-read tracking technique, when repOK() for class\nCompany is executed and the end for class Division is read, the execution of the method \\textit{repOK()} in class Division is triggered. In a similar way, the method \\textit{repOK()} is executed for classes Client and University. Following this technique, \\textit{Korat} generates test cases in terms of all the classes that can be reached from the owner class via an association end.\n\nWe initially include objects of type University, but the field that references the objects of type University is quickly identified as a do not care field, as explained in Section 0, reducing the size of the test case and consequentially the size of the input space.\n\nSince \\textit{Korat} does not support the use of collection types in the generation of test inputs, we wrote a simulator to support the UML implementation. There are more than two hundred test cases; we show five of them in Table 5.2. We ran the test cases in an Intel(R) Pentium(R) M 1.60GHz processor with 750Mb of RAM. The first test case is our own implementation of the University example. The last four test cases are from the UML2 v2.2.1 metamodel implementation. From our results that we can reduce between 96\\% and 99\\% of \\textit{Korat}'s test input space, where larger finitization shows greater reductions. We can also see that \\textit{Korat} can easily run timeout even with a small number of objects because \\textit{Korat} considers several non-relevant classes.\n\nEven without considering non-relevant classes, if the number of relationships related to the composition relationship is large, the test space can still be considerably large. One of the reasons the test input space we generate remains small in most cases is thanks to the principle of high decoupling in most software engineering projects. This principle requires a moderate number of relationships between two classes. Previous experiments based on eight industry standard software systems showed that most classes have between 1 and 10 relationships with the average number of relationships being 2.86 [49].\n5.2 Mutation Testing\n\nMutation testing is a technique used to evaluate the quality of a test suite [9]. In mutation testing, small modifications that imitate programmers errors are introduced in a program, and the resulting program is called a mutant. After generating a mutant, we evaluate the program using our test cases with the objective of detecting a difference in the behavior between the original program and the mutant just generated. When a difference in behavior is detected, it is said the mutant has been killed [9]. A high rate of killed mutants indicates a strong set of test cases. There are different types of mutation operations that can be applied to a program to generate a mutant. Table 5.3 shows the type of mutation operations that we applied when evaluating our test cases. The table also shows an example of the mutation produced by the operator.\n\nFigure 5.1: Property getOpposite() method.\n\nWe applied mutation testing to 21 methods, 2 of them from the UML specification, getName(), getOpposite(), and 19 automatically generated methods from the OCL constraints introduced by Booch et al. [8]. We generated a total of 383 mutants. To evaluate each mutant, the first step is to execute a set of test cases against the\noriginal program, and then on each of the generated mutants. The procedure to\ngenerate the set of test cases follows the approach described in Chapter IV. For each\nmethod, we take as input the program’s class diagram, with the method under test,\nand its OCL post condition, from which a post-method is generated to serve as test\noracle. A key difference in mutation testing is that even if no error is detected by the\nmethod’s post condition, if the output differs from the output of the original program\nthe mutant is still considered to be killed.\n\nAmong the 383 mutants generated, 360 were killed, for a 93.8% killing rate. In\nour experiments, non killed mutants are equivalent to the original code. For example,\nindex \\neq -1 is equivalent to index > -1, since, in the context of the method getOpposite,\nindex cannot take a value less than -1. Specifically, the non killed mutants are,\nfrom Table 5.4, mutant 4, 6, 7, and 8. For mutant 4, the behavior of the program\nremains the same as long as memberEnds is equal or greater than 2. In the case of\n6, 7, and 8, the variable index, as explained earlier, cannot take a value less than -1.\nIn all cases, the behavior of the program remains unaffected. It is important to note\nthat when applying a mutation operator, if the generated mutant is not valid, i.e., it\ncannot compile, the mutant is discarded. The code for the method getOpposite() is\nshown in Figure 5.1.\n\nWe also applied the small scope hypothesis based method to test the 383 mutants,\nwith 5 as the number of possible values for each of the variables. The small scope\nhypothesis based method killed 242, for a 73.8% killing rate. One of the reasons\nfor the lower killing rate is the reduced branch coverage achieved by the small scope\nhypothesis based method. While our approach can achieve 100% coverage, the small\nscope hypothesis method achieves only 70% coverage. Table 5.6 shows a summary of\nthe results with the list of the tested methods, number of mutants, number of killed\nmutants, and branch coverage achieved by each method.\n5.3 Path Condition Analysis\n\nWe evaluated our approach with two kinds of experiments: effectiveness and efficiency. Effectiveness can be evaluated by whether our approach is able to find real faults in some industry strength software systems. To evaluate the efficiency, we compared our approach to related techniques that can be applied to do consistency checking. The project we chose to do the experiments is Eclipse’s UML2 project [50], an EMF based UML implementation. One of the reasons for choosing the project is that it is large, with more than 300 meta-classes with large number of OCL constraints. These constraints include post conditions and well-formed rules. Also, being an open source project, it has a good bug report system which allowed us to confirm our findings.\n\n5.3.1 Effectiveness\n\nWhen we studied the UML specification [7], we found that many existing approaches that claimed to recover UML composition by reverse engineering from a Java program do not strictly follow the semantics of UML composition [7]. The UML specification requires that “If a composite is deleted, all of its parts are normally deleted with it. Note that a part can (where allowed) be removed from a composite before the composite is deleted, and thus not be deleted as part of the composite...” p. 41. However, many existing approaches require that all part objects cannot be accessed by any object except for its owner object. In fact, this is not the case. For instance, the class diagram excerpted from the UML specification in Figure 5.2 shows that an object of class Property, which is owned by an object of class Class, can be accessed by an object of class Association. Therefore, when an owner object does not exist, all of its owned objects should not exist. Namely, all the links to the owned objects from other live objects should be removed. Assume method destroy() intends to implement the deletion of an owner object, Figure 5.3 (a) shows the property as a\npost-condition after method _destroy_() is called on an owner object.\n\n\n\nFigure 5.2: Partial UML metamodel.\n\n\n\nFigure 5.3: UML metamodel post conditions.\n\nAfter the above observation, we applied our approach on one of the UML2 projects, i.e. the UML2 v1.1.1 implementation. We detected the implementation error of all fields derived from UML composition and was confirmed with one of UML2 project members. The root cause of the implementation error is that the _destroy_() method iteratively checks each object contained in the resource, which is supposed to contain all the instantiated objects, and remove their links to the owned objects being destroyed. But the resource object, as part of EMF metamodel, did not automatically store all instantiated owned objects in the resource object appropriately. For this OCL constraint, we found a total of 999 error instances. We also applied our approach to a later version UML2 v2.2.1 and the previous fault has been fixed.\n\nWe also used our approach to check a set of 55 well-formedness rules on the UML2 project v4.0.2. We detected a software fault, related to the OCL post condition for the method _isAttribute_() defined in the UML specification (p.125 [7]). Figure 5.4 shows the OCL post condition and the automatically generated Java Boolean method used as post method. The generated method includes the auxiliary methods OclOperations.allInstances() that implements the OCL allInstances operation, and OclOperations.includes() that implements the OCL operation includes. As an initial minimal test case, CCUJ instantiates class Property and null is used as the default\nvalue for the parameter p. After the initial minimal test case generation, CCUJ executes the method under test, `isAttribute()` and its post method, `post_isAttribute()`. The rest of the process follows as explained in Chapter IV. The reason of the fault was because the implementation only checks the non-navigable inverse references to property p, this is, the references in which an object (obj1) can access p, but p cannot directly access the object obj1. Since the reference attribute in class Classifier is a navigable inverse reference, it was ignored, and the method failed to return true when c.attribute->includes(p) is true. The problem was confirmed and fixed by the developers.\n\n```java\npublic static Boolean post_isAttribute(PropertyImpl p) {\n Iterator<?> it0 = ((Collection<?>) OclOperations.allInstances(\"Classifier\"))\n .iterator();\n Boolean r1 = false;\n if (((Collection<?>) OclOperations.allInstances(\"Classifier\"))\n .size() > 0) {\n while (it0.hasNext()) {\n Classifier c = (Classifier) it0.next();\n Boolean r0 = false;\n if (OclOperations.includes((Collection<Property>) c.getAttributes(), p)) {\n r0 = true;\n }\n r1 = r0;\n if (r0) {\n break;\n }\n }\n } else {\n r1 = true;\n }\n Boolean r2 = false;\n if (r1 == self.isAttribute()) {\n r2 = true;\n }\n return r2;\n}\n```\n\nFigure 5.4: OCL post condition and generated Java Boolean method.\n\n### 5.3.2 Efficiency\n\nTo determine the efficiency, we compared our approach with a glass box testing approach [11], and Korat [48], a black box testing approach, which are two prominent approaches, in terms of the number of generated test cases. One reason for this selection is that these two approaches consider different methods to generate test case values. The number of test cases determines the number of times that the\nmethod under test must be executed. Since our approach achieves branch coverage, the smaller the number of necessary test cases, the greater the efficiency. Both of Korat and the glass box testing approach use finitization to limit the number of values that can be assigned to a field. While the small scope hypothesis is the assumption of both approaches, they cannot be as effective as our approach since we explore different test cases to cover the branch coverage criteria. In the case of the glass box testing approach, the search space is pruned by ignoring fields not accessed during the execution of the method under test.\n\nTo compare our approach with Korat on the generation of the test input state space, we consider the Multiplicity and Navigability in a class diagram and convert these constraints into an invariant method \\textit{repOK()} that Korat uses to generate all test cases. For example, in Figure 5.2, \\textit{repOK()} in Class checks the multiplicity and navigability on Property’s end. Method \\textit{repOK()} in Property checks the multiplicity and navigability on both Class and Association’s end.\n\nThe results of the comparison for four methods from the UML2 project are shown in Table 5.7. The second column in the table shows the number of classes involved on each of the tests, which represents a fragment of the UML metamodel. Considering all the metamodel classes would greatly increase the number of test cases generated by the black box approach, since it would recursively call \\textit{repOK()} in all the classes involved. On the third column we have different finitization values, a 3 indicates that both the black box and glass box testing approaches would consider up to 3 different values for a given field during the test case generation. As opposed to our approach that considers all possible values. The fourth column shows the number of test cases generated by the glass box testing approach. For the method \\textit{maySpecializeType()}, since the method under test has only one parameter that can take up to 3-5 different values, depending on the finitization, and no extra fields are touched during the execution, the number of generated test cases is equal to the finitization number.\nFor the second method, extra fields are touched during the execution of the method under test, increasing the number of generated test cases. The fifth column shows the number of test cases generated by the black box testing approach. The number of test cases is determined by number of parameters, number of classes, and the associations between them, where each of the fields can take up to 3-5 values depending on the finitization. This results in a large number of test cases since the black box testing approach tries all possible combinations for all the fields involved. Finally, the last column shows the number of test cases generated by our approach.\nTable 5.2: Comparison with Korat.\n\n<table>\n<thead>\n<tr>\n<th>Finitization</th>\n<th>Number of Fields Read</th>\n<th>Number of Test Inputs</th>\n<th>Time to Generate Test Inputs</th>\n<th>Total Time to Test Inputs (ms)</th>\n<th>Number of Fields Read by Korat</th>\n<th>Number of Test Inputs by Korat</th>\n<th>Time to Generate Test Inputs by Korat (ms)</th>\n<th>Total Time to Test Inputs by Korat (ms)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>(1,1,2,2)</td>\n<td>4</td>\n<td>3</td>\n<td>2133.25 ms</td>\n<td>2275.07 ms</td>\n<td>8</td>\n<td>25</td>\n<td>2048.96 ms</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,2,3)</td>\n<td>4</td>\n<td>3</td>\n<td>2129.19</td>\n<td>2275.48</td>\n<td>9</td>\n<td>81</td>\n<td>2151.7</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,3,2)</td>\n<td>5</td>\n<td>4</td>\n<td>2172.04</td>\n<td>2315.42</td>\n<td>10</td>\n<td>125</td>\n<td>2429.84</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,4,2)</td>\n<td>6</td>\n<td>5</td>\n<td>2186.85</td>\n<td>2328.28</td>\n<td>12</td>\n<td>625</td>\n<td>2361.85</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,4,3)</td>\n<td>6</td>\n<td>5</td>\n<td>2196.66</td>\n<td>2339.11</td>\n<td>13</td>\n<td>6561</td>\n<td>2642.19</td>\n</tr>\n<tr>\n<td>2</td>\n<td>(1,1,1,1,2)</td>\n<td>7</td>\n<td>8</td>\n<td>2134.12</td>\n<td>2855.57</td>\n<td>10</td>\n<td>125</td>\n<td>2256.15</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,2,2)</td>\n<td>8</td>\n<td>12</td>\n<td>2214.36</td>\n<td>2935.72</td>\n<td>12</td>\n<td>625</td>\n<td>2343.75</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,2,3)</td>\n<td>8</td>\n<td>12</td>\n<td>2230.18</td>\n<td>2951.33</td>\n<td>13</td>\n<td>6561</td>\n<td>3062.41</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,2,2,3)</td>\n<td>10</td>\n<td>18</td>\n<td>2353.65</td>\n<td>3077.47</td>\n<td>15</td>\n<td>59049</td>\n<td>time out</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,2,2,4)</td>\n<td>10</td>\n<td>18</td>\n<td>2397.33</td>\n<td>3119.18</td>\n<td>16</td>\n<td>1419857</td>\n<td>time out</td>\n</tr>\n<tr>\n<td>3</td>\n<td>(1,1,1,1,1,1,2)</td>\n<td>7</td>\n<td>8</td>\n<td>2156.17</td>\n<td>2707.14</td>\n<td>12</td>\n<td>729</td>\n<td>2335.9</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,1,2,2)</td>\n<td>8</td>\n<td>12</td>\n<td>2296.73</td>\n<td>2943.62</td>\n<td>14</td>\n<td>6561</td>\n<td>2963.54</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,2,2,2)</td>\n<td>8</td>\n<td>12</td>\n<td>2284.25</td>\n<td>2951.57</td>\n<td>16</td>\n<td>83521</td>\n<td>time out</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,2,2,2,2)</td>\n<td>10</td>\n<td>18</td>\n<td>2313.58</td>\n<td>3136.75</td>\n<td>18</td>\n<td>1419857</td>\n<td>time out</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,2,2,3,2)</td>\n<td>10</td>\n<td>18</td>\n<td>2383.76</td>\n<td>3122.19</td>\n<td>20</td>\n<td>39135393</td>\n<td>time out</td>\n</tr>\n<tr>\n<td>4</td>\n<td>(1,1,1,1,1,1,1,1,1)</td>\n<td>7</td>\n<td>8</td>\n<td>2246.18</td>\n<td>2683.42</td>\n<td>13</td>\n<td>729</td>\n<td>2551.63</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,1,1,1,2)</td>\n<td>8</td>\n<td>8</td>\n<td>2312.01</td>\n<td>2893.8</td>\n<td>15</td>\n<td>4913</td>\n<td>2673.09</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,1,2,1,2,2)</td>\n<td>10</td>\n<td>12</td>\n<td>2293.27</td>\n<td>2912.47</td>\n<td>17</td>\n<td>83521</td>\n<td>time out</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,2,2,2,2)</td>\n<td>10</td>\n<td>18</td>\n<td>2243.13</td>\n<td>3284.42</td>\n<td>18</td>\n<td>1185921</td>\n<td>time out</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,2,2,2,2,2)</td>\n<td>10</td>\n<td>18</td>\n<td>2351.37</td>\n<td>3189.14</td>\n<td>20</td>\n<td>39135393</td>\n<td>time out</td>\n</tr>\n<tr>\n<td>5</td>\n<td>(1,1,1,1,1,1,1,1,1)</td>\n<td>7</td>\n<td>8</td>\n<td>2237.71</td>\n<td>2897.47</td>\n<td>15</td>\n<td>4913</td>\n<td>2783.85</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,1,1,1,1,2)</td>\n<td>7</td>\n<td>8</td>\n<td>2215.31</td>\n<td>2838.09</td>\n<td>16</td>\n<td>35937</td>\n<td>time out</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,1,2,1,2,2)</td>\n<td>8</td>\n<td>12</td>\n<td>2240.2</td>\n<td>3015.76</td>\n<td>18</td>\n<td>1185921</td>\n<td>time out</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,1,2,1,2,2)</td>\n<td>8</td>\n<td>12</td>\n<td>2236.18</td>\n<td>3093.24</td>\n<td>20</td>\n<td>17850625</td>\n<td>time out</td>\n</tr>\n<tr>\n<td></td>\n<td>(1,1,1,2,2,1,1,2,2)</td>\n<td>10</td>\n<td>18</td>\n<td>2312.49</td>\n<td>3121.1</td>\n<td>22</td>\n<td>1160290625</td>\n<td>time out</td>\n</tr>\n</tbody>\n</table>\n\nTable 5.3: Test case generation comparison.\n\n<table>\n<thead>\n<tr>\n<th>Mutation Operator</th>\n<th>Original Code</th>\n<th>Mutation Example</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Absolute Value Insertion</td>\n<td>x = 3 * a;</td>\n<td>x = 3 * abs (a);</td>\n</tr>\n<tr>\n<td>Arithmetic Operator Replacement</td>\n<td>x = a + b;</td>\n<td>x = a - b;</td>\n</tr>\n<tr>\n<td>Relational Operator Replacement</td>\n<td>if ( m > n )</td>\n<td>if ( m >= n )</td>\n</tr>\n<tr>\n<td>Conditional Operator Replacement</td>\n<td>if ( a && b )</td>\n<td>if ( a</td>\n</tr>\n<tr>\n<td>Assignment Operator Replacement</td>\n<td>x += 3;</td>\n<td>x -= 3;</td>\n</tr>\n<tr>\n<td>Unary Operator Insertion</td>\n<td>x = 3 * a;</td>\n<td>x = 3 * -a;</td>\n</tr>\n</tbody>\n</table>\nTable 5.4: Mutations for method getOpposite().\n\n<table>\n<thead>\n<tr>\n<th>#</th>\n<th>Line</th>\n<th>Mutation</th>\n<th>Type</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>3</td>\n<td>if (!property.isNavigable()) {</td>\n<td>Unary Operator Insertion</td>\n</tr>\n<tr>\n<td>2</td>\n<td>5</td>\n<td>if (association == null) {</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>3</td>\n<td>8</td>\n<td>if (memberEnds.size() != 2) {</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>4</td>\n<td>8</td>\n<td>if (memberEnds.size() > 2) {</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>5</td>\n<td>8</td>\n<td>if (memberEnds.size() < 2) {</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>6</td>\n<td>11</td>\n<td>if (index == -1) {</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>7</td>\n<td>11</td>\n<td>if (index > -1) {</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>8</td>\n<td>11</td>\n<td>if (index < -1) {</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>9</td>\n<td>16</td>\n<td>if (_association.getOwnedEnds().contains(otherEnd) ...</td>\n<td>Unary Operation Deletion</td>\n</tr>\n<tr>\n<td>10</td>\n<td>16</td>\n<td>... contains(otherEnd) & & association.getNavigableOwnedEnds() ...</td>\n<td>Conditional Operator Replacement</td>\n</tr>\n<tr>\n<td>11</td>\n<td>13</td>\n<td>... memberEnds).basicGet(Math.abs(index + 1)); ...</td>\n<td>Arithmetic Operator Replacement</td>\n</tr>\n<tr>\n<td>12</td>\n<td>13</td>\n<td>... memberEnds).basicGet(Math.abs(index * 1)); ...</td>\n<td>Arithmetic Operator Replacement</td>\n</tr>\n<tr>\n<td>13</td>\n<td>13</td>\n<td>... memberEnds).basicGet(Math.abs(index / 1)); ...</td>\n<td>Arithmetic Operator Replacement</td>\n</tr>\n</tbody>\n</table>\nTable 5.5: Mutations for method earn().\n\n<table>\n<thead>\n<tr>\n<th>#</th>\n<th>Line</th>\n<th>Mutation</th>\n<th>Type</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>2</td>\n<td>points -= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>2</td>\n<td>2</td>\n<td>points ^= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>3</td>\n<td>2</td>\n<td>points /= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>4</td>\n<td>2</td>\n<td>points %= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>5</td>\n<td>2</td>\n<td>points >= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>6</td>\n<td>2</td>\n<td>points <= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>7</td>\n<td>2</td>\n<td>points ^= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>8</td>\n<td>2</td>\n<td>points <<= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>9</td>\n<td>2</td>\n<td>points >>= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>10</td>\n<td>2</td>\n<td>points >>>= i</td>\n<td>Assignment Operator Replacement</td>\n</tr>\n<tr>\n<td>11</td>\n<td>2</td>\n<td>points += abs(i)</td>\n<td>Absolute Value Insertion</td>\n</tr>\n<tr>\n<td>12</td>\n<td>2</td>\n<td>points += -abs(i)</td>\n<td>Absolute Value Insertion</td>\n</tr>\n<tr>\n<td>13</td>\n<td>2</td>\n<td>points += failOnZero(i)</td>\n<td>Absolute Value Insertion</td>\n</tr>\n<tr>\n<td>14</td>\n<td>3</td>\n<td>if (points >= 100)</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>15</td>\n<td>3</td>\n<td>if (points < 100)</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>16</td>\n<td>3</td>\n<td>if (points <= 100)</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>17</td>\n<td>3</td>\n<td>if (points != 100)</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>18</td>\n<td>6</td>\n<td>if (points < 0)</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>19</td>\n<td>6</td>\n<td>if (points <= 0)</td>\n<td>Relational Operator Replacement</td>\n</tr>\n<tr>\n<td>20</td>\n<td>6</td>\n<td>if (points != 0)</td>\n<td>Relational Operator Replacement</td>\n</tr>\n</tbody>\n</table>\nTable 5.6: Mutation testing comparison.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>% Branch Coverage</th>\n<th># Mutants Killed</th>\n<th>% Mutants Killed</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>CCUJ Small Scope</td>\n<td># of Mutants CCUJ Small Scope</td>\n<td>CCUJ Small Scope</td>\n</tr>\n<tr>\n<td>earn()</td>\n<td>100% 66% 20</td>\n<td>19 19</td>\n<td>95% 95%</td>\n</tr>\n<tr>\n<td>getOpposite()</td>\n<td>100% 64% 13</td>\n<td>10 10</td>\n<td>76% 76%</td>\n</tr>\n<tr>\n<td>earn2()</td>\n<td>100% 82% 116</td>\n<td>110 42</td>\n<td>95% 36%</td>\n</tr>\n<tr>\n<td>ofAge()</td>\n<td>100% 71% 11</td>\n<td>10 5</td>\n<td>91% 45%</td>\n</tr>\n<tr>\n<td>checkDates()</td>\n<td>100% 100% 8</td>\n<td>8 8</td>\n<td>100% 100%</td>\n</tr>\n<tr>\n<td>knownServiceLevel()</td>\n<td>100% 70% 4</td>\n<td>4 2</td>\n<td>100% 50%</td>\n</tr>\n<tr>\n<td>correctCard()</td>\n<td>100% 100% 4</td>\n<td>4 4</td>\n<td>100% 100%</td>\n</tr>\n<tr>\n<td>levelAndColor()</td>\n<td>100% 78% 22</td>\n<td>22 10</td>\n<td>100% 45%</td>\n</tr>\n<tr>\n<td>minServices()</td>\n<td>100% 58% 11</td>\n<td>10 10</td>\n<td>91% 91%</td>\n</tr>\n<tr>\n<td>sizesAgree()</td>\n<td>100% 55% 18</td>\n<td>17 17</td>\n<td>94% 94%</td>\n</tr>\n<tr>\n<td>noAccounts()</td>\n<td>100% 54% 34</td>\n<td>32 32</td>\n<td>94% 94%</td>\n</tr>\n<tr>\n<td>numberOfParticipants()</td>\n<td>100% 58% 11</td>\n<td>10 10</td>\n<td>91% 91%</td>\n</tr>\n<tr>\n<td>numberOfParticipants2()</td>\n<td>100% 58% 11</td>\n<td>10 10</td>\n<td>91% 91%</td>\n</tr>\n<tr>\n<td>firstLevel()</td>\n<td>100% 70% 4</td>\n<td>4 4</td>\n<td>100% 50%</td>\n</tr>\n<tr>\n<td>isEmpty()</td>\n<td>100% 58% 11</td>\n<td>10 10</td>\n<td>91% 91%</td>\n</tr>\n<tr>\n<td>birthdayHappens()</td>\n<td>100% 58% 11</td>\n<td>10 10</td>\n<td>91% 91%</td>\n</tr>\n<tr>\n<td>upgradePointsEarned()</td>\n<td>100% 58% 11</td>\n<td>10 10</td>\n<td>91% 91%</td>\n</tr>\n<tr>\n<td>totalPoints()</td>\n<td>100% 79% 11</td>\n<td>10 7</td>\n<td>91% 64%</td>\n</tr>\n<tr>\n<td>totalPointsEarning()</td>\n<td>100% 71% 33</td>\n<td>31 20</td>\n<td>94% 61%</td>\n</tr>\n<tr>\n<td>totalPointsEarning2()</td>\n<td>100% 90% 19</td>\n<td>19 4</td>\n<td>100% 21%</td>\n</tr>\n<tr>\n<td>Average</td>\n<td>100.00% 70.02% 383</td>\n<td>360 242</td>\n<td>93.78% 73.87%</td>\n</tr>\n</tbody>\n</table>\nTable 5.7: Test case generation comparison.\n\n<table>\n<thead>\n<tr>\n<th>Test</th>\n<th>No. Classes</th>\n<th>Finitazation</th>\n<th>Glass Box</th>\n<th>Black Box</th>\n<th>Finitazation</th>\n<th>Our Approach</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Property::isAttribute()</td>\n<td>2</td>\n<td>3</td>\n<td>26</td>\n<td>6561</td>\n<td>⇐</td>\n<td>2</td>\n</tr>\n<tr>\n<td></td>\n<td>2</td>\n<td>4</td>\n<td>64</td>\n<td>65536</td>\n<td>⇐</td>\n<td>2</td>\n</tr>\n<tr>\n<td></td>\n<td>2</td>\n<td>5</td>\n<td>125</td>\n<td>390625</td>\n<td>⇐</td>\n<td>2</td>\n</tr>\n<tr>\n<td>StateMachine::ancestor()</td>\n<td>8</td>\n<td>3</td>\n<td>27</td>\n<td>6561</td>\n<td>⇐</td>\n<td>10</td>\n</tr>\n<tr>\n<td></td>\n<td>8</td>\n<td>4</td>\n<td>64</td>\n<td>65536</td>\n<td>⇐</td>\n<td>10</td>\n</tr>\n<tr>\n<td></td>\n<td>8</td>\n<td>5</td>\n<td>125</td>\n<td>390625</td>\n<td>⇐</td>\n<td>10</td>\n</tr>\n<tr>\n<td>Classifier::isTemplate()</td>\n<td>4</td>\n<td>3</td>\n<td>108</td>\n<td>2916</td>\n<td>⇐</td>\n<td>6</td>\n</tr>\n<tr>\n<td></td>\n<td>4</td>\n<td>4</td>\n<td>256</td>\n<td>16384</td>\n<td>⇐</td>\n<td>6</td>\n</tr>\n<tr>\n<td></td>\n<td>4</td>\n<td>5</td>\n<td>500</td>\n<td>62500</td>\n<td>⇐</td>\n<td>6</td>\n</tr>\n<tr>\n<td>Element::destroy()</td>\n<td>3</td>\n<td>3</td>\n<td>27</td>\n<td>531441</td>\n<td>⇐</td>\n<td>3</td>\n</tr>\n<tr>\n<td></td>\n<td>3</td>\n<td>4</td>\n<td>64</td>\n<td>16777216</td>\n<td>⇐</td>\n<td>3</td>\n</tr>\n<tr>\n<td></td>\n<td>3</td>\n<td>5</td>\n<td>125</td>\n<td>244140625</td>\n<td>⇐</td>\n<td>3</td>\n</tr>\n</tbody>\n</table>\nCHAPTER VI\n\nCONCLUSIONS\n\nThis dissertation presents two consistency checking approaches. The first is based on a bounded exhaustive testing technique with test input space pruning. Our pruning technique is based on do not care fields that detects fields that are not relevant for the method under test. Our technique was able to reduce the number of required test cases and successfully detect errors in two industry strength UML projects [50]. However, our exhaustive testing technique includes some drawbacks, namely, it does not guarantee a full exploration of the possible execution paths in the method under test, which may result in missing test cases that could expose a problem in the implementation, and a lack of efficiency compared to an approach that leverages information about previous executions when generating test cases, e.g., test case generation based on branch coverage, bounded exhaustive test case generation is more inefficient. Our second approach addresses these concerns. In our second approach we introduce a consistency checking technique that uses a testing-based validation technique that combines coverage criteria and dynamic symbolic execution with path conditions analysis to reduce the number of input states without sacrificing accuracy. It extends traditional lazy initialization for minimum test case generation from a class diagram, and extends universal symbolic execution to work with Java bytecode for consistency checking. Our approach was applied to multiple methods with invariants\nand post conditions in UML implementation projects, and was able to detect multiple errors while efficiently generating a small number of test cases. Some of the drawbacks of our approach are related to the limitations on SAT solver. Our approach only supports as data types basic arrays, objects, and integer types, and basic path condition constructs. Floating type numbers are not supported. As a future work we intend to expand support for multiple data types and path conditions.\nIn the following subsections we present each of the association properties in more detail and give examples of its use in a class diagram. Also we use the Object Constraint Language (OCL) to strictly define each of the properties at M2 and M1 level. The formalization of the association properties allows us to find deviations between a UML class diagram and its implementation in terms of the different types of association relationships. The following sections are organized as follows: for each property, we present its definition based on the UML specification, a formal definition using the OCL language at M2 level, the algorithm used to generate the properties constraints at M1 level, and an example of the generated M1 level constraints.\n\nA.1 Navigability\n\nAs previously introduced, navigability on an association relationship is used to specify the accessibility of class instances. Navigability is represented by an arrow on the navigable end, if both ends are navigable, the arrows are normally omitted. The class diagram in Figure A.1(a) shows an example of unidirectional navigability,\nwhere an instance of class Division can efficiently access an instance of class Client but not the opposite way. On Figure A.1(b) the navigability is bidirectional.\n\nA.1.1 Navigability Constraint at M2 Level\n\nThe navigability constraint is defined for the Association context. Using Figure A.1(a) as an example, for each member end on the association, \\( m_1 = \\text{clients}, m_2 = \\text{divisions} \\), if member end \\( m_1 \\) is navigable, the instance associated with the opposite member end \\( m_2 \\) must have a reference to the instance associated with the navigable member end \\( m_1 \\). In Figure A.2, the instance div1 is associated with the navigable member end \\( m_1 \\), and instance cli1 is associated with the opposite member end \\( m_2 \\). The instance div1 must have a reference to instance cli1.\n\n\\[\n\\text{context Association}\n\\text{inv: self.memberEnd->forall(m1, m2 | m1 <> m2 implies (m1.isNavigable(self) implies m2.hasReferenceTo(m1, self)))}\n\\]\n\nIn the constraint, the method isNavigable() returns true if the member end is navigable, e.g., the method would return true for member end \\( m_1 \\) (clients), and\nfalse for member end m2 (divisions). The method hasReference() returns true if the instance associated with member end m2 (div1 in Figure A.2) has a reference to the instance associated with the member end m1 (cli1 in Figure A.2). More details about auxiliary operations, such as isNavigable(), can be found in Section 0.\n\nA.1.2 Algorithm to Generate Navigability Constraint at M1 Level\n\nThe algorithm to generate navigability constraints at M1 works as follows: for every association in the model that is not unidirectional (it has at least two navigable member ends) the algorithm selects its navigable member ends and for each pair-wise combination it generates a pair of constraints, one for each member end.\n\nfor each association ‘a’ in the model\n\n// selects navigable member ends\nlet ends : Set(Property) = a.memberEnd->reject(m | a.ownedEnd->includes(m))\n\nif ends size >= 2\nends->forall(e1, e2 | e1 <> e2, generate constraints )\n\n// values in square brackets are resolved from the model\ncontext e1:[e1 type]\ninv: e1.[e2 name]->forall(e2 | e2.[e1 name]->includes(e1))\n\ncontext e2:[e2 type]\ninv: e2.[e1 name]->forall(e1 | e1.[e2 name]->includes(e2))\n\nA.1.3 Navigability Constraint at M1 Level\n\nUsing the class diagram in Figure A.1(b) as an example, we automatically generate two OCL constraint for each of the navigable member ends in the diagram that are part of a bidirectional association. For this example a total of 2 OCL constraints are generated. Each constraint checks that, for each pair of classes, C1 and C2, that are part of a bidirectional association, if an object of type C1 has a reference to an object of type C2, the object of type C2 must also have a reference to the object of type C1.\nA.2 Multiplicity\n\nThe multiplicity of an association end constraints the number of references between the instances of the participating classes in the association. Multiplicity can be specified by a single number or a range in the form “a..b”, where “a” represents the lower multiplicity and “b” represents the upper multiplicity. An “*” can be used to represent an unlimited upper multiplicity. As an example, Figure A.1(b), the multiplicity “0..5” on Client’s end specifies that an instance of class Division can have a reference to 0 or at most 5 instances of class Client. The “*” on Division’s end indicates that an instance of class Client can have a reference to 0 or an unlimited number of instances of class Division.\n\nSome associations can also include a qualifier property, a property used to group a set of elements in a member end with a multiplicity greater than 1. For example, the class diagram in Figure A.3 shows the qualifying property LineId, this property is part of the class Items. This means that an instance of class Invoice can have a reference to no more than 5 instances of class Item with the same LineId, but it can have a reference to more than 5 if LineId is different.\nA.2.1 Multiplicity Constraint at M2 Level\n\nThe multiplicity constraint is defined for the meta-class Class context. For each instance i of class self, and for each association a where self is a participating class, we count the number of links or instances of a where i is referenced. The number of references must be within the multiplicity range for that particular association.\n\n\\[\n\\text{context Class} \\\\\n\\text{inv: self.instances() -> forAll(i | Association.allInstances() -> forAll(a | a.memberEnd -> forAll(ml, m2 | ml.type = self and ml <> m2 and a.links() -> size() > 0 implies if m2.qualifier -> size() = 0 then checkCount(linksFor(a, i, ml) -> size(), m2) else checkQualifying(a, i, ml, m2) endif))}\n\\]\n\nIn the constraint, the operation allInstances() returns a collection with all the instances of meta-class Association. The operation checkCount() returns true if the number of links (linksFor()) is within the multiplicity range for the member end m2. The operation checkQualifying() is similar to checkCount() but it takes into consideration the qualifying property.\n\n\n\nA.2.2 Algorithm to Generate Multiplicity Constraint at M1 Level\n\nFor each association in the model, the algorithm selects the navigable member ends and generates a constraint for each. The algorithm considers two scenarios related to the multiplicity type, the first one when the multiplicity is set to exactly 1 and the second one when the multiplicity is given by a range with a non-infinity upper bound. The outline of the algorithm is as follows:\n\n\\[\n\\text{for each association 'a' in the model}\n\\]\nA.2.3 Multiplicity Constraint at M1 Level\n\nA multiplicity constraint is automatically generated for each member end with a bounded multiplicity. As an example, in Figure A.4, one OCL constraint is generated for clients member end with a bounded multiplicity of 1..5.\n\n```\ncontext div : Division\ninv : div.clients ->size () <= 5 and div.clients ->size () >= 1\n```\n\nA.3 Subsetting\n\nA subsetting association is defined by the UML specification as follows:\n\n“Subsetting represents the familiar set-theoretic concept. It is applicable to the collections represented by association ends, not to the association itself. It means that the subsetting association end is a collection that is either equal to the collection that it is subsetting or a proper subset of that collection. (Proper subsetting implies that the superset is not empty and that the subset has fewer members.) Subsetting is a relationship in the domain of extensional semantics. [7]” p. 40. The class diagram in Figure A.5 shows an example where properties b1 and b2 on class A1 subset property b on class A. This means that the collection contained in property b1 and property b2, is a subset of the collection contained in property b.\nA.3.1 Subsetting Constraint at M2 Level\n\nThe subsetting constraint is defined for the meta-class Class context. For each instance i of class self, if self is a participating class on a subsetting association, the instance i must be part of the union set of all subsetting association.\n\n```\ncontext Class\ninv : self.instances() -> forAll (i | self.subsettingAssociations() -> forAll (a | self.valuesForAssociation(a, i) -> forAll (l | self.isSubset(i, l, self.allSubsettedValues(a, i)))))\n```\n\nThe constraint uses several auxiliary operations, namely, instances(), subsettingAssociations(), valuesForAssociation(), isSubset(), and allSubsettedValues(). For more information about these methods, please refer to Section 0.\n\nA.3.2 Algorithm to Generate Subsetting Constraint at M1 Level\n\nThe algorithm to generate subsetting constraints at M1 works as follows: for every association in the model we select the navigable member ends that subset at least one property. The generated constraint checks if the values in the subsetting property are included in at least one of the subsetted properties.\n\n```\nfor each association 'a' in the model\na.memberEnd -> forAll (ml | generate constraints)\nif not a.ownedEnd -> includes(ml) and ml.redefinedProperty is not empty\nlet R = ml.redefinedProperty\n// the values inside square brackets are resolved from the model\ncontext c : [ml ownerClass type]\n```\nA.3.3 Subsetting Constraint at M1 Level\n\nFor the subset property, we generate an OCL constraint for each of the subsetting properties and the subsetted property. As an example, in Figure A.5 we generate an OCL constraint for the subsetting properties b1 and b2, and one for the subsetted property b. The constraints check that each element in the subsetting properties is also an element of the subsetted property.\n\ncontext a : A1\ninv: a . b1 ->forall ( x | a .oclAsType(A) . b->includes ( x ))\n\ncontext a : A1\ninv: a . b2 ->forall ( x | a .oclAsType(A) . b->includes ( x ))\n\nA.4 Union\n\nAn association end can be marked as a union to show that the end is derived by the union of its subsets. On Figure A.5, property b on class A is the union of properties b1 and b2 on class A1.\n\nA.4.1 Union Constraint\n\nOn the meta-class Class context, if class self is part of a union, every instance i of class self must be part of at least one of the subsetting sets.\n\ncontext Class\ninv: self .instances () ->forall ( i | self .unionAssociations () ->forall ( a | a . memberEnd ->forall ( p | p .isDerivedUnion implies\n\n108\nself.propertyValues(p, a, i)->includesAll(self.unionSubsetValues(p, i)) and\nself.unionSubsetValues(p, i)->includesAll(self.propertyValues(p, a, i)))\n\nThe constraint uses the OCL method includesAll() that checks if a collection includes all the elements in a second collection. The constraint also uses three auxiliary operations, unionAssociations(), propertyValues(), and unionSubsetValues().\n\nA.4.2 Algorithm to Generate Union Constraint at M1 Level\n\nFor each association in the model the algorithm selects the navigable member ends that are subsetted at least once and generate a constraint using the following template.\n\n```plaintext\nfor each association ‘a’ in the model\na.memberEnd->forAll(m1 | generate constraints)\n\nif not a.ownedEnd->includes(m1) // if m1 is navigable\nlet R be all properties redefining m1\n// the values inside square brackets are resolved from the model\ncontext c:[R[0] type]\ninv: c.oclAsType([R[0] ownerClass]).[m1 name]->forAll(x |\nc.[r[0] name]->includes(x)\n\ncontext c:[R[n] type]\ninv: c.oclAsType([R[1] ownerClass]).[m1 name]->forAll(x |\nc.[r[n] name]->includes(x)\n```\n\nA.4.3 Union Constraint at M1 Level\n\nFor the union property, we generate an OCL constraint for the union property b. The constraints checks that each element in the property must be part of at least one of the subsetting properties.\n\n```plaintext\ncontext a:A1\ninv: a.oclAsType(A).b->forAll(b | a.b1->includes(b))\n\ncontext a:A1\ninv: a.oclAsType(A).b->forAll(b | a.b2->includes(b))\n```\nA.5 Redefinition\n\nA redefining association is defined by the UML specification as follows:\n\n“Redefinition is a relationship between features of classifiers within a specialization hierarchy. Redefinition may be used to change the definition of a feature, and thereby introduce a specialized classifier in place of the original featuring classifier, but this usage is incidental. The difference in domain (that redefinition applies to features) differentiates redefinition from specialization. [7]” 40.\n\nA redefining association must remain consistent with the redefined association with respect of its type and multiplicity constraints. The type of the redefining property must be a subtype of the redefined property and the lower and upper multiplicity range must be contained on the lower and upper multiplicity range of the redefined property.\n\nA.5.1 Redefinition Constraint\n\nThe redefinition constraint is defined for the Association context. For each member end \\( m \\) in the association, the constraint checks whether each redefining property \\( r \\) is consistent with the multiplicity values of \\( m \\).\n\n```context Association\ninv: self.memberEnd->forAll(m | m.redefinedProperty->size() > 0 implies m.redefinedProperty->forAll(r | m.type.conformsTo(r.type) and if r.upperValue.oclAsType(LiteralUnlimitedNatural).value < 0 then m.upperValue.oclAsType(LiteralUnlimitedNatural).value <= r.upperValue.oclAsType(LiteralUnlimitedNatural).value endif and m.lowerValue.oclAsType(LiteralInteger).value >= r.lowerValue.oclAsType(LiteralInteger).value ))\n```\n\nA.5.2 Algorithm to Generate Redefinition Constraint at M1 Level\n\nFor each pair of redefined and redefining properties, we use the algorithms previously introduced to generate the navigability, multiplicity, subsetting, and union\nA.5.3 Redefinition Constraint at M1 Level\n\nFor a redefining property, we automatically generate a constraint for each of the properties previously defined, i.e. navigability, multiplicity, subsetting, and union. The constraints are generated following the same approach. A true evaluation of the redefining property implies a true evaluation of the redefined property. Also, a violation of the redefined property implies a violation of the redefining property.\n\nA.6 Composition\n\nAccording to the UML specification, a composite aggregation, or composition, is a strong form of aggregation. Composition is a subtype of the whole-part relationship. A whole-part relationship indicates that an element is composed by one or more parts (elements). A composition can be represented in a class diagram as a solid/filled black diamond and is differentiated from a regular aggregation by the aggregationKind property. Its representation is defined in the UML specification as follows:\n\n“An association with aggregationKind = shared differs in notation from binary associations in adding a hollow diamond as a terminal adornment at the aggregate end of the association line. The diamond shall be noticeably smaller than the diamond notation for associations. An association with aggregationKind = composite likewise has a diamond at the aggregate end, but differs in having the diamond filled in” [7] p. 42.\n\nThe diagram in Figure A.6 shows the aggregate end as a filled diamond next to class Company. In this example, class Company is a composite class, and class Division is the part class of the composite aggregation.\n\nThe semantics of composition applies certain constraints on the relationship between instances of the composite and part classes, i.e., instances of class Company\nand instances of class Division respectively.\n\n“If a composite is deleted, all of its parts are normally deleted with it. Note that a part can (where allowed) be removed from a composite before the composite is deleted, and thus not be deleted as part of the composite. Compositions may be linked in a directed acyclic graph with transitive deletion characteristics; that is, deleting an element in one part of the graph will also result in the deletion of all elements of the subgraph below that element. Composition is represented by the isComposite attribute on the part end of the association being set to true” [7] p. 41.\n\nWe call the above constraint the lifetime property, because it is related to the lifetime of the composite and its parts. In essence, this property requires that if a composite is removed, its parts should also be removed.\n\nAlso from the UML specification, we can see the concept of the lifetime property exemplified in the following sentences, where classifier refers to a composite class:\n\n“A part declares that an instance of this classifier may contain a set of instances by composition. All such instances are destroyed when the containing classifier instance is destroyed” [7] p. 184.\n\nThe following fragment of the UML specification describes one more constraint:\n\n“An association may represent a composite aggregation (i.e., a whole/part relationship). Only binary associations can be aggregations. Composite aggregation is a strong form of aggregation that requires a part instance be included in at most one composite at a time” [7] p. 41.\n\nThe above constraint is related to how a part can be shared among different composites. The constraint specifies that a part should not be shared by more than one composition at a time. We call this constraint the shareability property.\nA.6.1 Composition Constraints\n\nA.6.1.1 Shareability\n\nWe define the global shareability constraint for the meta-class Class context. The constraint first checks if self is an owned class, if true, we check that for every instance of self oc, and for every two composite classes where self is the part class, there is not more than one link at a time from an owner object.\n\n```\ncontext Class\ninv: self.isOwnedClass() implies self.instances() -> forall (oc |\n self.ownerCompositions() -> forall (comp1, comp2 | not (comp1 <>\n comp2 and\n oc.linkExist(comp1, comp2)))))\n```\n\nA.6.1.2 Lifetime\n\nFor the lifetime property, our constraint first checks if self is a composite class, then for each instance of self i, if i is deleted, each instance of part classes oci owned by i should also be deleted.\n\n```\ncontext Class\ninv: self.isCompositeClass() implies self.instances() -> forall (i |\n i.isUndefined() implies self.ownedClasses() -> forall (oc |\n oc.instances() -> forall (oci | i.ownsObject(oci)\n implies oci.isUndefined())))))\n```\n\nA.6.2 Algorithm to Generate Composition Constraint at M1 Level\n\nThe Lifetime Constraint is defined as post-condition for the method implementing the lifetime property. For each class in the model that is an owner class we generate two constraints as follows:\n\n```\nfor each class c in the model that is an owner class\nlet P be all navigable association member ends of type c\n\n// the values inside square brackets are resolved from the model\ncontext [c name]::[methodName]() : Boolean\n```\nfor each class c in the model that is an owner class\nlet M be the set of composite member ends owned by c, for each m in M\nlet P be the set of navigable association member ends of the same\n type of m\n\n// the values inside square brackets are resolved from the model\ncontext [c name]::[methodName]() : Boolean\npost: self.[m name]->forAll(x | [P[0] ownerClass].allInstances(y | y.[P[0] name]->excludes(x)) and\n[P[1] ownerClass].allInstances(y | y.[P[1] name]->excludes(x)) and\n...\n[P[n] ownerClass].allInstances(y | y.[P[n] name]->excludes(x))\n\nA.6.3 Composition Constraint at M1 Level\n\nFor the class diagram in Figure A.6, the following constraint, as a post-condition\nof the method destroy, checks that no instance of class Client has a reference to the\ndestroyed division object.\n\ncontext Company::destroy()\npost: self.div->forAll(x | Client.allInstances(y | y.divisions->excludes(x)))\n\nAlso, for the shareability property we generate one OCL constraint for each pos-\nsible combination of composition pairs that share the same part class. For the class\ndiagram in Figure A.7, we generate the following four constraints.\ncontext factory: Factory\ninv: factory.car->forAll ( car | Customer.allInstances()->forAll ( c | not c.car->includes(car)) )\n\ncontext customer: Customer\ninv: customer.car->forAll ( car | Factory.allInstances()->forAll ( f | not f.car->includes(car)) )\n\nA.7 Composition Constraint Auxiliary Operations\n\nA.7.1 isComposition()\n\nReturns true if self is a composite association, otherwise false.\n\nclass Association\ndef: isComposition() : Boolean =\nself.memberEnd->exists (me | me.isComposite )\n\nA.7.2 isCompositeClass()\n\nReturns true if self is a composite class, otherwise false.\n\nclass Class\ndef: isCompositeClass() : Boolean =\nself.superClasses()->exists (c | Property.allInstances()->exists (p | p.isComposite and p.getOtherEnd().type = c))\n\nA.7.3 superClasses()\n\nReturns a set of classes that are super classes of class self.\n\nclass Class\ndef: superClasses() : Set(Class) =\n Class.allInstances() select (c | self.conformsTo(c))\n\nA.7.4 ownedClasses()\n\nReturns a set of classes owned (part classes) by class self.\n\nclass Context Class\ndef: ownedClasses() : Set(Class) =\n Class.allInstances() select (c |\n Property.allInstances() exists (p |\n p.isComposite and c.superClasses() includes (s |\n p.type = s and p.getOtherEnd().type = self)))\n\nA.7.5 isOwnedClass()\n\nReturns true if class self is owned by another class, otherwise false.\n\nclass Context Class\ndef: isOwnedClass() : Boolean =\n Class.allInstances() exists (c |\n c.ownedClasses() includes (self))\n\nA.7.6 compositions()\n\nReturns the set of composite associations in the model.\n\nclass Context Class\ndef: compositions() : Set(Association) =\n Association.allInstances() select (a |\n a.isComposition())\n\nA.7.7 instances()\n\nReturns a set with all the instances of class self.\n\nclass Context Class\ndef: instances() : Set(InstanceSpecification) =\n InstanceSpecification.allInstances() select (i |\n i.classifier includes (self))\nA.7.8 isUndefined()\n\nReturns true if the instance self is undefined.\n\n```java\ncontext InstanceSpecification\ndef: isUndefined(): Boolean =\n InstanceSpecification.allInstances() -> forAll(\n i | i.slot -> forAll(s | Association.allInstances() -> forAll(\n a | i.classifier -> includes(a) implies s.value -> forAll(\n v | v.oclAsType(InstanceValue).instance <> self)))\n```\n\nA.7.9 ownerCompositions()\n\nReturns a set of composite associations where self is the owned class.\n\n```java\ncontext Class\ndef: ownerCompositions(): Set(Association) =\n compositions() -> select(c1 |\n c1.memberEnd -> exists(m |\n m.isComposite and m.type = self))\n```\n\nA.7.10 ownsObject(i:InstanceSpecification)\n\nReturns true if the instance self owns the insntace i, otherwise false.\n\n```java\ncontext InstanceSpecification\ndef: ownsObject(i: InstanceSpecification): Boolean =\n self.slot -> exists(s | s.value -> exists(v | v.oclAsType(InstanceValue).instance = i))\n```\n\nA.7.11 linkExist(a1:Association, a2:Association)\n\nReturns true if the instance self is referenced by a link of type a1 and a link of type a2 simultaneously.\n\n```java\ncontext InstanceSpecification\ndef: linkExist(a1: Association, a2: Association): Boolean =\n InstanceSpecification.allInstances() -> exists(\n link1, link2 | link1 <> link2 and\n link1.classifier -> includes(a1) and\n link2.classifier -> includes(a2) and\n link1.slot -> exists(s | s.value -> exists(\n```\n\\text{v | v.oclsAsType(InstanceValue).instance = self })\n\\text{and link2.slot->exists(s | s.value->exists(v | v.oclsAsType(InstanceValue).instance = self )))}\n**RIGOROUS ANALYSIS OF THE ALGORITHM IN PATH CONDITION ANALYSIS**\n\n**Structural Operational Semantics of Concolic Execution**\n\nSR-SymVar-Seq: \\( v \\) is a symbolic expression\n\\[\n<v; e_1, \\omega> \\rightarrow <e_1, \\omega>\n\\]\n\nSR-Read-Field\n\\[\n\\omega.\\gamma(v) \\neq \\text{null} \\quad <v.f, \\omega> \\rightarrow <\\omega.\\Gamma(v.f), \\omega[[C: (\\omega.C)(v!) = \\text{null}]]><true> >\n\\]\n\nSR-Field-Assignment\n\\[\n\\omega.\\gamma(v) \\neq \\text{null} \\quad <v.f = v_1, \\omega> \\rightarrow <v_1, \\omega[[\\gamma:\\omega.\\gamma((v.f) = v_1).\\Gamma:\\omega.\\Gamma(v.f) = v_1)].C:((\\omega.C)(v!) = \\text{null}][true] >\n\\]\n\nSR-If\n\\[\n\\begin{align*}\n<\\text{if true then } e_1 \\text{ else } e_2, \\omega> &\\rightarrow <e_1, \\omega> \\\\\n<\\text{if false then } e_1 \\text{ else } e_2, \\omega> &\\rightarrow <e_2, \\omega>\n\\end{align*}\n\\]\n\nSR-While\n\\[\n<\\text{while}_{k} e_0 \\text{ do } e_1, \\omega> \\rightarrow <\\text{if } e_0 \\text{ then } e_1; \\text{while}_{k-1} e_0 \\text{ do } e_1 \\text{ else } \\text{skip}, \\omega> \\quad \\text{if } k > 0\n\\]\n\nSR-New\n\\[\n\\alpha \\notin \\text{HOS} \\quad f \\text{ is a set of fields of } C\n\\quad <\\text{new } C, \\omega> \\rightarrow <\\alpha, \\omega[[\\gamma:\\omega.\\gamma((\\alpha.f) = (null)).\\Gamma:\\omega.\\Gamma((\\alpha.f) = (null))]>]\n\\]\n\nSR-Method-Call\n\\[\n\\omega.\\gamma(v) \\neq \\text{null} \\quad \\text{mbody}(m,v) = x.e\n\\quad <v.m(\\overline{v}), \\omega> \\rightarrow <e[\\overline{v}/x, \\text{v/this}], \\omega[[C: (\\omega.C)(v!) = \\text{null}][true] >]\n\\]\n\nSR-EQ-T\n\\[\n\\omega.\\gamma(v_0) == \\omega.\\gamma(v_1)\n\\quad <v_0 == v_1, \\omega> \\rightarrow <\\text{true}, \\omega[[C: \\omega.C(v_0 == v_1)]][true] >\n\\]\n\nSR-EQ-F\n\\[\n\\omega.\\gamma(v_0) != \\omega.\\gamma(v_1)\n\\quad <v_0 == v_1, \\omega> \\rightarrow <\\text{true}, \\omega[[C: \\omega.C(v_0 == v_1)]][false] >\n\\]\nSR-AND-T\n\\[ \\omega.\\gamma(v_0) == true \\]\n\\[ < v_0 && e_1, \\omega > \\rightarrow< e_1, \\omega[C: \\omega. C(v_0 == true)] > \\]\n\nSR-AND-F\n\\[ \\omega.\\gamma(v_0) == false \\]\n\\[ < v_0 && e_1, \\omega > \\rightarrow< false, \\omega[C: \\omega. C(v_0 == true)] > \\]\n\nSR-OR-T\n\\[ \\omega.\\gamma(v_0) == true \\]\n\\[ < v_0 || v_1, \\omega > \\rightarrow< true, \\omega[C: (v_0 == true)] > \\]\n\nSR-OR-F\n\\[ \\omega.\\gamma(v_0) == false \\]\n\\[ < v_0 || v_1, \\omega > \\rightarrow< v_1, \\omega[C: (v_0 == true)] > \\]\n\nSR-NOT-T\n\\[ \\omega.\\gamma(v_0) == true \\]\n\\[ < !v_0, \\omega > \\rightarrow< false, \\omega[C: (v_0 == true)] > \\]\n\nSR-NOT-F\n\\[ \\omega.\\gamma(v_0) == false \\]\n\\[ < !v_0, \\omega > \\rightarrow< true, \\omega[C: (v_0 == true)] > \\]\n\n**Structural Operational Semantics of Concrete Execution**\n\nS-Const-Seq:\n\\[ v \\text{ is constant} \\]\n\\[ < v,e_1,s > \\rightarrow< e_1,s > \\]\n\nS-Read_Field\n\\[ v \\neq null \\]\n\\[ < v.f,s > \\rightarrow< s(v,f),s > \\]\n\nS-Field-Assignment\n\\[ v \\neq null \\]\n\\[ < v.f = v_1,s > \\rightarrow< v_1,s [(v,f) \\leftarrow v_1] > \\]\nS-If\n\n\\[\n<\\text{if true then } e_1 \\text{ else } e_2, s > \\rightarrow < e_1, s >\n\\]\n\n\\[\n<\\text{if false then } e_1 \\text{ else } e_2, s > \\rightarrow < e_2, s >\n\\]\n\nS-While\n\n\\[\n<\\text{while } e_0 \\text{ do } e_1, s > \\rightarrow < \\text{if } e_0 \\text{ then } e_1; \\text{while } e_{k-1} e_0 \\text{ do } e_1 \\text{ else skip}, s >\n\\]\n\nif \\( k > 0 \\)\n\nS-New\n\n\\[\n\\alpha \\notin \\text{HOS} \\quad \\bar{f} \\text{ is a set of fields of } C\n\\]\n\n\\[\n<\\text{new } C, s > \\rightarrow < \\alpha, s[(\\alpha, \\bar{f}) \\mapsto \\{\\text{null}\\}] >\n\\]\n\nS-Method-Call\n\n\\[\nv \\neq \\text{null} \\quad \\text{mbody}(m, v) = \\bar{x}.e\n\\]\n\n\\[\n<v.m(\\bar{v}_1), s > \\rightarrow < e[\\bar{v}_1/\\bar{x}, \\ v/\\text{this}], s >\n\\]\n\nS-EQ-T\n\n\\[\n< v_0 == v_0, s > \\rightarrow < \\text{true}, s >\n\\]\n\nS-EQ-F\n\n\\[\nv_0 ! = v_1\n\\]\n\n\\[\n< v_0 == v_1, s > \\rightarrow < \\text{false}, s >\n\\]\n\nS-AND-T\n\n\\[\n< \\text{true } \\&\\& e_1, s > \\rightarrow < e_1, s >\n\\]\n\nS-AND-F\n\n\\[\n< \\text{false } \\&\\& e_1, s > \\rightarrow < \\text{false}, s >\n\\]\n\nS-OR-T\n\n\\[\n< \\text{true } || v_1, s > \\rightarrow < \\text{true}, s >\n\\]\n\nS-OR-F\n\n\\[\n< \\text{false } || v_1, s > \\rightarrow < v_1, s >\n\\]\nNext we need prove the following lemmas and theorems.\n\n**Lemma 1:** For any state $s$, $\\omega_s = (\\langle \\omega_s, \\gamma, \\omega, \\Gamma, \\omega_s, C \\rangle)$ is the corresponding concolic state, and $e$ is an expression, if $\\langle e, \\omega_s \\rangle \\rightarrow \\langle e', \\omega_s' \\rangle$ then\n\ni) If $\\langle e', \\omega_s' \\rangle$ is an error configuration $\\bot$ in concolic execution, then $\\langle s(e'), s(\\omega_s'), \\Gamma \\rangle$ is an error configuration $\\bot$ in the concrete execution.\n\nii) If $\\omega_s, C$ is satisfied by $s$ then $\\omega_s', C$ is satisfied by $s$.\n\niii) For any state $\\sigma$, if $\\omega_s', C$ is satisfied by $\\sigma$, then $\\omega_s, C$ is satisfied by $\\sigma$.\n\niv) For any state $\\sigma$ whose concolic state is $\\langle \\omega_\\sigma, \\gamma, \\omega, \\Gamma, \\omega_\\sigma, C \\rangle$ such that $\\omega_\\sigma, C = \\omega_s, C$, if $\\omega_s', C$ is satisfied by $\\sigma$, then 1) $\\langle \\sigma(e), \\sigma(\\omega_\\Gamma) \\rangle \\rightarrow \\langle \\sigma(e'), \\sigma(\\omega_\\Gamma') \\rangle$; and 2) $\\omega_\\sigma', C = \\omega_s', C$\n\n**Proof:** If $\\langle e', \\omega_s' \\rangle$ is an error heap configuration $\\bot$ then $e'$ is one of the following forms: i) null.$f$; ii) null.$f = v_A$; iii) null.$m(v_A)$; or iv) while$_0$ $e_0$ do $e_1$. Therefore, the corresponding concrete expression $s(e')$ should be one of the above four forms and so $\\langle s(e'), s(\\omega_\\Gamma) \\rangle$ is an error heap configuration $\\bot$ in the concrete execution (no rules can be applied). We conclude the proof of i).\nTo prove ii), we observe that the rules of the structural operational semantics of concolic execution can be divided into two groups based on how $P'$ is generated\n\n1) $P' \\equiv P$\n\n2) $P' \\equiv P \\land r$\n\nFor group 1, the rules include SR-SymVar-Seq. Since $\\omega_s'. C$ is $\\omega_s. C$, the conclusion is valid.\n\nFor group 2, the rules include SR-Read_Field. $s$ satisfies $r$ since it is part of the premise of the rule.\n\nTo prove iii), we observe that $\\omega_s. C$ is part of $\\omega_s'. C$ and the conclusion is valid.\n\nWe prove iv) by the structural induction on the expression $e$. Let state $s$ be an any state and its concolic state is $\\omega_s$.\n\n1. Rule SR-SymVar-Seq i.e. $e$ is $v; e_1$: we have $< v; e_1, \\omega_s > \\rightarrow < e_1, \\omega_s >$ and if $\\omega_s. C_s$ is satisfied by $\\sigma$ then we prove $< \\sigma(v; e_1), \\sigma(\\omega. \\Gamma) > \\rightarrow < \\sigma(e_1) >$.\n\n$\\sigma(\\omega. \\Gamma) >$. Let state $\\sigma$ be such a state and its concolic state is $< \\omega_\\sigma, \\gamma, \\omega. \\Gamma >$.\n\n$\\omega_\\sigma. C >$ where $\\omega_\\sigma. C = \\omega_s. C$ and $\\omega_\\sigma. \\gamma = \\sigma$. Then $< \\sigma(v; e_1), (\\omega. . ) > = < \\sigma(v); \\sigma(e_1), \\sigma(\\omega. \\Gamma) >$. Since $v$ is a symbolic expression, $\\sigma(v)$ is a constant too. By R-Cons-Seq, we have $< \\sigma(v); \\sigma(e_1), (\\omega. \\Gamma) > \\rightarrow < \\sigma(e_1), (\\omega. \\Gamma) >$, and so this concludes the first part. Since the C part of the symbolic state is not changed in this transition, this concludes the second part.\n2. Rule SR-Read_Field i.e. e is v.f: we have\n\n\\[<v.f, \\omega_s> \\rightarrow <\\omega.\\Gamma(v.f), \\omega_s[C:(\\omega_s.C)(v! = null)^{l.true}>] \\] and if \\(\\omega_s'.C\\) is satisfied by \\(\\sigma\\) and its concolic state is \\(<\\omega_s'.y, \\omega_s.\\Gamma, \\omega_s.C>\\) where \\(\\omega_s.C = \\omega_s'.C\\) and \\(\\omega_s.y = \\sigma\\), then we prove \\(<\\sigma(v.f), \\sigma(\\omega.\\Gamma)> \\rightarrow <\\sigma(\\omega.\\Gamma(v.f)), \\sigma(\\omega.\\Gamma)>\\). Since \\(\\omega_s'.C\\) is satisfied by \\(\\sigma\\), \\(\\sigma(v) \\neq null\\). By rule R-Read_Field, we have \\(<\\sigma(v.f), \\sigma(\\omega.\\Gamma)> \\rightarrow <\\sigma(v.f), \\sigma(\\omega.\\Gamma)>\\). Then, we have \\(\\sigma(\\omega.\\Gamma(v.f)) = \\sigma(\\omega.\\Gamma(v.f)) = \\sigma(v, f)\\). This concludes the first part. Since \\(\\omega_s.C = \\omega_s'.C\\), both \\(\\omega_s'.C\\) and \\(\\omega_s'.C\\) add \\((v! = null)^{l.true}\\) to the original ones. So this concludes the second part.\n\n3. Rule SR-Field-Assignment i.e.e is v.f: we have \\(<v.f = v_1, \\omega_s> \\rightarrow <v_1, \\omega_s[y: \\omega_y.y[(v, f) \\leftrightarrow v_1], \\Gamma: \\omega_s.\\Gamma[(v, f) \\leftrightarrow v_1], C: \\omega_s.C(v! = null)]^{l.true}>\\] and if \\(\\omega_s'.C\\) is satisfied by \\(\\sigma\\) and its concolic state is \\(<\\omega_s'.y, \\omega_s.\\Gamma, \\omega_s.C>\\) where \\(\\omega_s.C = \\omega_s'.C\\) and \\(\\omega_s.y = \\sigma\\), then we prove \\(<\\sigma(v.f = v_1), \\sigma(\\omega_s'.\\Gamma)>\\) where \\(\\omega_s' = \\omega_s[y: \\omega_y.y[(v, f) \\leftrightarrow v_1], \\Gamma: \\omega_s.\\Gamma[(v, f) \\leftrightarrow v_1], C: \\omega_s.C(v! = null)]^{l.true}>\\). We have \\(<\\sigma(v.f = v_1), \\sigma(\\omega.\\Gamma) = <\\sigma(v.f) = \\sigma(v_1), \\sigma(\\omega.\\Gamma) = <\\sigma(v.f) = \\sigma(v_1), \\sigma(\\omega.\\Gamma) >\\).\n\nSince \\(\\omega_s'.C\\) is satisfied by \\(\\sigma\\), \\(\\sigma(v) != null\\), by rule R-Field-Assignment, we have \\(<\\sigma(v.f) = \\sigma(v_1), \\sigma(\\omega.\\Gamma) > \\rightarrow <\\sigma(v_1), \\sigma[\\omega_s.\\Gamma[(v, f) \\leftrightarrow \\sigma(v_1)]>\\).\n\nSince \\(\\sigma(\\omega.\\Gamma(v)) = \\sigma(v)\\), we conclude the first part. Since \\(\\omega_s.C = \\omega_s'.C\\), both \\(\\omega_s'.C\\) and \\(\\omega_s'.C\\) add \\((v! = null)^{l.true}\\) to the original ones. So this concludes the second part.\n\n4. Rule SR-While i.e.e is while \\(e_0\\) do \\(e_1\\): we have \\(<\\text{while}_k e_0 \\text{ do } e_1, \\omega_s> \\rightarrow <\\text{if } e_0 \\text{ then } e_1; \\text{while}_k e_0 \\text{ do } e_1 \\text{ else skip}, \\omega_s>\\) and if \\(\\omega_s'.C\\) is satisfied\n\n124\nby \\( \\sigma \\) and its concolic state is \\(< \\omega_\\sigma, \\gamma, \\omega, \\Gamma, \\omega_\\sigma.C >\\) where \\( \\omega_\\sigma.C = \\omega_s.C \\) and \\( \\omega_\\sigma.y=\\sigma \\), then we prove \\(<\\sigma(\\text{while}_k e_0 \\text{ do } e_1)\\), \\(\\sigma(\\omega, \\Gamma)\\)\\>\n\n\\[\\rightarrow <\\sigma(\\text{if } e_0 \\text{ then } e_1; \\text{while}_{k-1} e_0 \\text{ do } e_1 \\text{ else skip})\\), \\(\\sigma(\\omega, \\Gamma)\\)\\) assuming \\(k>0\\).\n\n\\(<\\sigma(\\text{while}_k e_0 \\text{ do } e_1)\\), \\(\\sigma(\\omega, \\Gamma)\\)\\) = \\(<\\text{while}_k \\sigma(e_0) \\text{ do } \\sigma(e_1), \\sigma(\\omega, \\Gamma)\\>). By R-While, we have\n\n\\(<\\text{while}_k \\sigma(e_0) \\text{ do } \\sigma(e_1), \\sigma(\\omega, \\Gamma)\\)\\>\\[\\rightarrow <\\]\n\nif \\(\\sigma(e_0)\\) then \\(\\sigma(e_1); \\text{while}_{k-1} \\sigma(e_0) \\text{ do } \\sigma(e_1) \\text{ else skip}, \\sigma(\\omega, \\Gamma) >\\). So this concludes the first part. Since the C part of the symbolic state is not changed in this transition, this concludes the second part.\n\n5. Rule SR-New, i.e. \\(e\\) is new \\(C\\): we have \\(<\\text{new } C, \\omega_s >\\) \\[\\rightarrow <\\alpha, \\omega_s' >\\]\n\nwhere \\(\\omega_s' = \\omega_s[y: \\omega_s. y[(\\alpha, \\bar{f}) \\rightarrow \\{\\text{null}\\}], \\Gamma: \\omega. \\Gamma[(\\alpha, \\bar{f}) \\rightarrow \\{\\text{null}\\}]\\]\n\nand if \\(\\omega_s'.C\\) is satisfied by \\(\\sigma\\) and its concolic state is \\(<\\omega_\\sigma, \\gamma, \\omega, \\Gamma, \\omega_\\sigma.C >\\) where \\(\\omega_\\sigma.C = \\omega_s.C \\) and \\(\\omega_\\sigma.y=\\sigma\\), then we prove \\(<\\sigma\\) (new \\(C\\),\n\n\\(\\sigma(\\omega, \\Gamma) \\rightarrow <\\sigma(\\alpha), \\sigma(\\omega'.\\Gamma)\\)\\). Since \\(\\alpha \\notin \\text{HOS}\\) holds, we take the same \\(\\alpha\\) used by SR-New and we have \\(<\\sigma\\) (new \\(C\\), \\(\\sigma(\\omega, \\Gamma) >=<\\text{new } C,$\n\n\\(\\sigma(\\omega, \\Gamma) \\rightarrow <\\alpha, \\sigma(\\omega, \\Gamma)[(\\alpha, \\bar{f}) \\rightarrow \\{\\text{null}\\}] \\rightarrow <\\sigma(\\alpha),(\\omega'.\\Gamma) >\\). So this concludes the first part. Since the C part of the symbolic state is not changed in this transition, this concludes the second part.\n\n6. Rule SR-Method_Call, i.e. \\(e\\) is \\(v_0.m(\\bar{v_1})\\): we have \\(<v, m(\\bar{v}_1), \\omega_s >\\) \\[\\rightarrow <e[\\bar{v}_1/\\bar{x}, v/\\text{this}], \\omega_s' >\\] where \\(\\omega_s' = \\omega_s[C: (\\omega_s.C)(v! = \\text{null})]\\)\n\nand, if \\(\\omega_s'.C\\) is satisfied by \\(\\sigma\\) and its concolic state is \\(<\\omega_\\sigma, \\gamma, \\omega, \\Gamma, \\omega_\\sigma.C >\\) where \\(\\omega_\\sigma.C = \\omega_s.C \\) and \\(\\omega_\\sigma.y=\\sigma\\), then we prove\n\n\\(<\\sigma(v.m(\\bar{v}_1)), \\sigma(\\omega, \\Gamma)\\)\\[\\rightarrow <\\sigma(e[\\bar{v}_1/\\bar{x}, v/\\text{this}], \\sigma(\\omega'.\\Gamma) >\\]. Since \\(\\sigma\\)\nsatisfies $\\omega_s'.C$, $\\sigma(v) != \\text{null}$ holds. $<\\sigma(v.m(v_1)), \\sigma(\\omega.\\Gamma)> =<\\sigma(v).m(\\sigma(v_1)), \\sigma(\\omega.\\Gamma)> \\rightarrow<\\sigma[e[\\sigma(\\bar{v}_1)/\\bar{x}], \\sigma(v)/\\text{this}], \\sigma(\\omega.\\Gamma)> =<\\sigma(e[\\bar{v}_1/\\bar{x}, v/\\text{this}], \\sigma(\\omega'.\\Gamma) > (\\omega'.\\Gamma \\text{ is not updated in the target configuration}). So this concludes the first part. Since $\\omega_s'.C = \\omega_s.C$, both $\\omega_s'.C$ and $\\omega_s'.C$ add $(v! = \\text{null})^{ltrue}$ to the original ones. So this concludes the second part.\n\n7. Rule SR-EQ-T, i.e. e is $v_0 == v_1$: we have $<v_0 == v_1, \\omega_s > \\rightarrow< true, \\omega_s' >$ where $\\omega_s' = \\omega_s[C: \\omega_s.C(v_0 == v_1)^{ltrue}]$ and, if $\\omega_s'.C$ is satisfied by $\\sigma$ and its concolic state is $<\\omega_s.\\gamma, \\omega.\\Gamma, \\omega_s.C>$ where $\\omega_s.C = \\omega_s'.C$ and $\\omega_s.\\gamma = \\sigma$, then we prove $<\\sigma(v_0 == v_1), \\sigma(\\omega.\\Gamma) > \\rightarrow<\\sigma(\\text{true}), \\sigma(\\omega'.\\Gamma) >. <\\sigma(v_0 == v_1), \\sigma(\\omega.\\Gamma) > =<\\sigma(v_0) ==\\sigma(v_1), \\sigma(\\omega.\\Gamma) >=<\\sigma(v_0) ==\\sigma(v_1), \\sigma(\\omega.\\Gamma) > \\rightarrow<\\sigma(\\text{true}), \\sigma(\\omega'.\\Gamma) >$ (\\omega'.\\Gamma \\text{ is not updated in the target configuration}). So, this concludes the first part. Since $\\omega_s.C = \\omega_s.C$, both $\\omega_s'.C$ and $\\omega_s'.C$ add $(v_0 == v_1)^{ltrue}$ to the original ones. So this concludes the second part.\n\nSame proof for the SR-EQ-F. In the same manner, we can prove SE-EQ-F.\n\n8. Rule SR-AND-T, i.e. e is $v_0 && e_1$: we have $<v_0 && e_1, \\omega_s > \\rightarrow< e_1, \\omega_s' >$ where $\\omega_s' = \\omega_s[C: \\omega_s.C(v_0 == \\text{true})^{ltrue}]$ and, if $\\omega_s'.C$ is satisfied by $\\sigma$ and its concolic state is $<\\omega_s.\\gamma, \\omega.\\Gamma, \\omega_s.C>$ where $\\omega_s.C = \\omega_s.C$ and $\\omega_s.\\gamma = \\sigma$, then we prove $<\\sigma(v_0 && e_1), \\sigma(\\omega.\\Gamma) > \\rightarrow<\\sigma(e_1), \\sigma(\\omega'.\\Gamma) >$.\n\nSince $\\sigma$ satisfies $\\omega_s'.C$, $\\sigma(v_0) == \\text{true}$ holds, by S-AND-T, we have $<\\sigma(v_0 && e_1), \\sigma(\\omega.\\Gamma) >=<\\sigma(v_0) && \\sigma(e_1), \\sigma(\\omega.\\Gamma) > \\rightarrow<$\n\\( \\sigma(e_1), \\sigma(\\omega. \\Gamma) =< \\sigma(e_1), \\sigma(\\omega'. \\Gamma) > \\) (\\( \\omega'. \\Gamma \\) is not updated in the target configuration). So, this concludes the first part. Since \\( \\omega_{\\sigma}. C = \\omega_{\\sigma}. C \\), both \\( \\omega_{\\sigma}'. C \\) and \\( \\omega_{\\sigma}'. C \\) add \\( (v_0 == \\text{true})^{<l, \\text{true}>} \\) to the original ones. So this concludes the second part. In the same manner, we can prove SE-OR-T and SE-OR-F.\n\n9. Rule SR-NOT-T, i.e \\( e \\) is \\( ! v_0 \\): we have \\( < ! v_0, \\omega_s > \\rightarrow < \\text{false}, \\omega_s' > \\)\n\nwhere \\( \\omega_s' = \\omega_s[C: \\omega_s. C(v_0 == \\text{true})^{<l, \\text{true}>}] \\) and, if \\( \\omega_s'. C \\) is satisfied by \\( \\sigma \\) and its concolic state is \\( < \\omega_{\\sigma}. y, \\omega. \\Gamma, \\omega_{\\sigma}. C > \\) where \\( \\omega_{\\sigma}. C = \\omega_{\\sigma}. C \\) and \\( \\omega_{\\sigma}. y = \\sigma \\), then we prove \\( \\sigma(! v_0), \\sigma(\\omega. \\Gamma) > \\rightarrow^* < \\sigma(\\text{false}), \\sigma(\\omega'. \\Gamma) > \\).\n\nSince \\( \\sigma \\) satisfies \\( \\omega_{\\sigma}. C \\), \\( \\sigma(v_0) == \\text{true} \\) holds, by S-NOT-T, we have\n\n\\( < \\sigma(! v_0), \\sigma(\\omega. \\Gamma) > = < ! \\sigma(v_0), \\sigma(\\omega. \\Gamma) > \\rightarrow < \\text{false}, \\sigma(\\omega. \\Gamma) > \\) (\\( \\omega'. \\Gamma \\) is not updated in the target configuration). So this concludes the first part. Since \\( \\omega_{\\sigma}. C = \\omega_{\\sigma}. C \\), both \\( \\omega_{\\sigma}'. C \\) and \\( \\omega_{\\sigma}'. C \\) add\n\n\\( (v_0 == \\text{true})^{<l, \\text{true}>} \\) to the original ones. So this concludes the second part.\n\nIn the same manner, we can prove SR-NOT-F.\n\n\\textbf{Lemma 2}: For any state \\( s \\) whose symbolic state is \\( \\omega_s = < \\omega_s, y, \\omega. \\Gamma, \\{ \\} > \\), if \\( < e, \\omega_s > \\rightarrow^* < e', \\omega_s' > \\) then\n\ni) If \\( < e', \\omega_s' > \\) is an error concolic configuration \\( \\perp \\), then \\( < s(e'), s(\\omega'. \\Gamma) > \\) is an error heap configuration \\( \\perp \\) in the concrete execution\n\nii) State \\( s \\) satisfies \\( \\omega_s'. C \\).\n\niii) For state \\( \\sigma \\), if \\( \\sigma \\) satisfies \\( \\omega_s'. C \\) and \\( \\omega_{\\sigma} = < \\omega_{\\sigma}, y, \\omega. \\Gamma, \\{ \\} > \\) is the corresponding concolic state, then \\( \\omega_s'. C = \\omega_{\\sigma}'. C \\).\niv) For state $\\sigma$, if $\\sigma$ satisfies $\\omega_s'.C$, then $<\\sigma(e), \\sigma> \\rightarrow^* <\\sigma(e'), \\sigma(\\omega,\\Gamma)>\n\nProof: We prove i) by induction on the length $n$ of the chain of symbolic reductions.\n\n1. Base case, when $n=0$, i.e. $<e',\\omega_s'>=<e, \\omega_s>$ is $\\perp$. Then $<e,\\omega_s'>$ should be one of the following four configurations:\n - $<\\text{null.f}, \\omega_s'>$\n - $<\\text{null.f}=e, \\omega_s'>$\n - $<\\text{null.m}(\\vec{v}), \\omega_s'>$\n - $<\\text{while}_0 e_0 \\text{ do } e_1, \\omega_s'>$\n\nTherefore $<s(e'),s(\\omega,\\Gamma)>$ should be an error heap configuration too.\n\n2. Induction step: assume i) is valid for any $n=k-1$. We consider the following two cases:\n - If $<e, \\omega_s> \\rightarrow^{k-1} <e', \\omega_s'>$ and $<e', \\omega_s'>$ is $\\perp$, then $<s(e'),s(\\omega,\\Gamma)>$ is $\\perp$ by induction. So there is no $k$th reduction from $<e', \\omega_s'>$.\n - If $<e, \\omega_s> \\rightarrow^{k-1} <e', \\omega_s'>$ and $<e', \\omega_s'>$ is not $\\perp$ so we have a rule to be applied and the next configuration is $<e', \\omega_s'> \\rightarrow <e'', \\omega_s''>$ and $<e'', \\omega_s''>$ is an error configuration. Then similar to the base case, $<e'', \\omega_s''>$ has one of the four error configurations. Therefore, $<s(e''),s(\\omega,\\Gamma)>$ should be an error heap configuration too.\n\nWe prove ii) by induction on the length $n$ of the chain of symbolic reductions.\n\n1. Base case when $n=0$, i.e. $<e, \\omega_s>$ where $\\omega.C=\\{}$. State $s$ satisfies $\\omega_s.C$.\n\n2. Induction step: assume ii) is valid for any $n=k-1$. We will prove for the state $s$, if $<e, \\omega_s> \\rightarrow^{k} <e'', \\omega_s''>$ then $s$ satisfies $\\omega''.C$. $<e, \\omega_s> \\rightarrow^{k} <e'', \\omega_s'>$\ncan be broken into \\( \\langle e, \\omega_s \\rangle \\rightarrow^{k-1} \\langle e', \\omega_s' \\rangle \\rightarrow \\langle e''', \\omega_s''' \\rangle \\). By induction, \\( s \\) satisfies \\( \\omega_s'.C \\). By lemma 1 (ii), \\( s \\) satisfies \\( \\omega''.C \\).\n\nWe prove iii) by induction on the length \\( n \\) of the chain of symbolic reductions\n\n1. Base case when \\( n = 0 \\), i.e. \\( \\langle e, \\omega_s \\rangle = \\langle e', \\omega_s' \\rangle \\) where \\( \\omega_s.C = \\{ \\} \\). Then for all state \\( \\sigma \\), we have \\( \\omega_s'.C = \\omega_{s'}'.C \\).\n\n2. Induction Step: assume iii) hold for any \\( n = k-1 \\). We will prove for any state \\( \\sigma \\), if \\( \\sigma \\) satisfies \\( \\omega_s'.C \\), then \\( \\langle \\sigma(e), \\sigma \\rangle \\rightarrow^* \\langle \\sigma(e'), \\sigma(\\omega'.\\Gamma) \\rangle \\). \\( \\langle e, \\omega_s \\rangle \\rightarrow^k \\langle e', \\omega_s' \\rangle \\) can be broken into \\( \\langle e, \\omega_s \\rangle \\rightarrow^{k-1} \\langle e'', \\omega_s'' \\rangle \\rightarrow \\langle e', \\omega_s' \\rangle \\). Since \\( \\sigma \\) satisfies \\( \\omega_s'.C \\), by lemma 1 (iii) \\( \\sigma \\) satisfies \\( \\omega_s''.C \\). By induction for \\( n=k-1 \\), \\( \\omega_s''.C = \\omega_{s''}.C \\) holds. Next by lemma 1 (iv)(2) and \\( \\langle e'', \\omega_s'' \\rangle \\rightarrow \\langle e', \\omega_s' \\rangle \\), we have \\( \\omega_s'.C = \\omega_{s'}'.C \\). This concludes the case.\n\nWe prove iv) by induction on the length \\( n \\) of the chain of symbolic reductions\n\n1. Base case when \\( n = 0 \\), i.e. \\( \\langle e, \\omega_s \\rangle = \\langle e', \\omega_s' \\rangle \\) where \\( \\omega_s.C = \\{ \\} \\). Then for all state \\( \\sigma \\), we have \\( \\langle (e), \\sigma \\rangle = \\langle \\sigma(e'), \\sigma(\\omega'.\\Gamma) \\rangle \\) immediately.\n\n2. Induction Step: assume iv) hold for any \\( n = k-1 \\). We will prove for any state \\( \\sigma \\), if \\( \\sigma \\) satisfies \\( \\omega_s'.C \\), then \\( \\langle \\sigma(e), \\sigma \\rangle \\rightarrow^* \\langle \\sigma(e'), \\sigma(\\omega'.\\Gamma) \\rangle \\). \\( \\langle e, \\omega_s \\rangle \\rightarrow^k \\langle e', \\omega_s' \\rangle \\) can be broken into \\( \\langle e, \\omega_s \\rangle \\rightarrow^{k-1} \\langle e'', \\omega_s'' \\rangle \\rightarrow \\langle e', \\omega_s' \\rangle \\). Since \\( \\sigma \\) satisfies \\( \\omega_s'.C \\), by lemma 1 (iii) \\( \\sigma \\) satisfies \\( \\omega_s''.C \\). By induction for \\( n=k-1 \\), \\( \\langle \\sigma(e), \\sigma \\rangle \\rightarrow^* \\langle \\sigma(e''), \\sigma(\\omega''.\\Gamma) \\rangle \\) holds. Next by lemma 1 (iv)(1), from \\( \\langle e'', \\omega_s'' \\rangle \\rightarrow \\langle e', \\omega_s' \\rangle \\) and \\( \\omega_s''.C = \\omega_{s''}.C \\) (using lemma 2(iii)), we have \\( \\langle \\sigma(e''), \\sigma(\\omega''.\\Gamma) \\rangle \\rightarrow \\langle \\sigma(e'), \\sigma(\\omega'.\\Gamma) \\rangle \\). This concludes the case.\nThis concludes our proof.\n\n**Lemma 3:** For any state $s$ whose symbolic state is $\\omega_s = \\langle \\omega_s, y, \\omega, \\Gamma, \\{\\}\\rangle$, assume $\\langle e_1; e_2, \\omega_s \\rangle \\rightarrow^{*} \\langle e_2, \\omega_{s_1} \\rangle \\rightarrow^{*} \\langle e, \\omega_{s_2} \\rangle$ and let $pc_1$ be $\\omega_{s_1}.C$ and $pc_2$ be $\\omega_{s_2}.C - \\omega_{s_1}.C$. For any state $\\sigma$ whose concolic state is $\\omega_\\sigma = \\langle \\omega_\\sigma, y, \\omega, \\Gamma, \\{\\}\\rangle$ such that $\\sigma$ satisfies $\\omega_{s_1}.C$. If $pc_1 \\Rightarrow pc_2$ is a tautology, then $\\omega_{s_2}.C = \\omega_{\\sigma_2}.C$.\n\n**Proof:** For any state $s$ whose symbolic state is $\\omega_s = \\langle \\omega_s, y, \\omega, \\Gamma, \\{\\}\\rangle$, assume $\\langle e_1; e_2, \\omega_s \\rangle \\rightarrow^{*} \\langle e_2, \\omega_{s_1} \\rangle$. Then any state $\\sigma$ whose concolic state is $\\omega_\\sigma = \\langle \\omega_\\sigma, y, \\omega, \\Gamma, \\{\\}\\rangle$ such that $\\sigma$ satisfies $\\omega_{s_1}.C$, we have $\\omega_{s_1}.C = \\omega_{\\sigma_1}.C$ by lemma 2 iii). Since $pc_1 \\Rightarrow pc_2$ is a tautology and $\\sigma$ satisfies $\\omega_{s_1}.C(=pc_1)$, $\\sigma$ satisfies $pc_2$. So $\\sigma$ satisfies $\\omega_{s_2}.C$.\n\nConsider $\\langle e_1; e_2, \\omega_s \\rangle \\rightarrow^{*} \\langle e, \\omega_{s_2} \\rangle$ and $\\sigma$ satisfies $\\omega_{s_2}.C$, we have $\\omega_{s_2}.C = \\omega_{\\sigma_2}.C$ by lemma 2 (iii).\n\n**Theorem 1:** At the end of the execution of $Concolic_{CCUI}$ on the expression $\\alpha . m; \\alpha . m_{post}$, the set $B$ should satisfy the following properties:\n\ni. $B$ contains the finite number of path constraints\n\nii. $B$ contains all path constraints in $\\alpha . m; \\alpha . m_{post}$\n\n**Proof:** We first prove i). We add a new path constraint to $B$ after the concolic execution of $\\alpha . m; \\alpha . m_{post}$. Note $k$ is set for the execution bound of a loop structure and so the number of path conditions in a path constraint is bounded. And each path condition has at most two branches, either true or false. So, the number of path constraints in $B$ is finite.\n\nWe next prove ii). Assume $B$ misses one path constraint which is $(l_1, b_1)$ $(l_2, b_2)\\ldots (l_i, b_i)\\ldots (l_n, b_n)$ where $l_i \\in LabelName, b_i$ is either $true$ or $false$, and\n\\[ i = \\{1, 2, \\ldots, n\\} \\]. Then we find the longest path constraint \\( \\text{lpc} \\) in \\( \\text{B} \\) that shares the longest prefix of the missing path constraint. Formally, \\( \\text{lpc} = (l_1, b_1) (l_2, b_2) \\ldots (l_i, b_i) \\ldots (l_k, b_k) \\) where \\( i \\) is the largest number from 1 to \\( n \\). Note algorithm \\( \\text{Conc}_\\text{Symb}_\\text{Exe} \\) pops a top element from \\( \\text{stack}_\\text{pc} \\) if 1) the top element has been flipped, 2) the path constraint consisting of \\( \\text{stack}_\\text{pc}[1] \\wedge \\ldots \\wedge \\neg \\text{stack}_\\text{pc}[\\text{top}] \\wedge \\text{Pre} \\) is not satisfiable, or the path constraint consisting of \\( \\text{stack}_\\text{pc}[i+1] \\wedge \\ldots \\wedge \\text{stack}_\\text{pc}[\\text{top}] \\) is produced by method \\( \\alpha \\cdot \\text{m} \\), denoted as \\( \\text{pc}_1 \\) and the path constraint consisting of \\( \\text{stack}_\\text{pc}[1] \\wedge \\ldots \\wedge \\text{stack}_\\text{pc}[i] \\) is produced by method \\( \\alpha \\cdot \\text{m}_\\text{post} \\), denoted as \\( \\text{pc}_2 \\), and \\( \\text{pc}_1 \\Rightarrow \\text{pc}_2 \\) is tautology and the top element is any of path conditions from \\( \\text{pc}_2 \\). Now back to our case. If \\( \\text{pc}_i \\)'s flipped value is \\textit{true}, from \\( \\text{lpc} \\) in \\( \\text{B} \\), then there are two cases where \\( \\text{pc}_i \\)'s flipped value: 1) \\( (l_1, b_1) \\wedge (l_2, b_2) \\wedge \\ldots \\wedge (l_i, b_i) \\wedge \\text{Pre} \\) is satisfiable, 2) \\( \\text{pc}_i \\) is not flappable, i.e. the path condition from one of SR-Read-Field, SR-Field-Assignment, and SR-Method-Call. Since \\( (l_1, b_1) (l_2, b_2) \\ldots (l_i, b_i) \\) is part of the missing path condition, we ensure \\( (l_1, b_1) (l_2, b_2) \\ldots (l_i, b_i) \\) is satisfiable. So, it should be in \\( \\text{B} \\) and this contradicts our assumption that \\( \\text{lpc} \\) is the longest path constraint in \\( \\text{B} \\). If \\( (l_1, b_1) (l_2, b_2) \\ldots (l_i, b_i) \\) is not satisfiable combined with \\( \\text{Pre} \\), then it contradicts the assumption of the missing path constraint. If \\( (l_1, b_1) (l_2, b_2) \\ldots (l_{i-1}, b_{i-1}) \\), denoted as \\( \\text{pc}_1 \\), in \\( \\text{lpc} \\) is the path constraint of \\( \\alpha \\cdot \\text{m} \\) and \\( (l_i, \\neg b_i) \\ldots (l_k, b_k) \\), denoted as \\( \\text{pc}_2 \\), in \\( \\text{lpc} \\) is the path constraint of \\( \\alpha \\cdot \\text{m}_\\text{post} \\) and \\( \\text{pc}_1 \\Rightarrow \\text{pc}_2 \\) is a tautology, then it contradicts lemma 3 which shows both path constraints in \\( \\alpha \\cdot \\text{m}_\\text{post} \\) are the same.\n\n**Theorem 2**: Assume \\( \\text{Concolic}_\\text{CCUJ} \\) can terminate. If \\( \\text{Concolic}_\\text{CCUJ} \\) returns true if and only if for any state \\( s \\), if \\( s \\) satisfies \\( \\text{Pre} \\) (denoted as \\( \\text{Pre}(s) \\)), then \\( (\\langle \\alpha \\cdot \\text{m}, s \\rangle \\rightarrow^* < e', \\)\nAssume Concolic_CCUJ returns true. Notice $S$ is initialized to $\\text{Pre}$ at line 1. At line 2, there are two possibilities for the condition for the while statement:\n\ni) If $S$ is not satisfiable, then there is no concrete state satisfying $S$. Then, the conclusion is valid.\n\nii) If $S$ is satisfiable we need to prove that $I$ is a loop invariant.\n\n- If $S$ is satisfiable and let $s$ be such a state that satisfies $S$, then $\\text{Pre}(s)$.\n- If $S$ is not satisfiable, then for any state $s$ if $\\text{Pre}(s) \\Rightarrow \\text{Method}(s) \\land \\text{Post}(s)$\n\nThe invariant holds at the beginning of the while loop statement since it is under the false branch of the if statement at line 2. Assume we find a state $s$, whose corresponding concolic state is $<\\omega.\\gamma, \\omega.\\Gamma, \\{}>$ and at line 6, the concolic execution results in $<\\alpha . m, <\\omega.\\gamma, \\omega.\\Gamma, \\{}>> \\rightarrow^* <\\epsilon', <\\omega_m.\\gamma, \\omega_m.\\Gamma, \\{}>>$. Since Concolic_CCUJ returns true, then the condition of line 7 is not true so line 8 is skipped. By Lemma 2, we have for any $\\sigma$, including $s$, such that $\\sigma$ satisfies $\\omega_m.\\Gamma, <\\alpha . m, \\sigma(\\omega.\\Gamma)> \\rightarrow^* <\\sigma(\\epsilon'), \\sigma(\\omega_m.\\Gamma)>$\nholds. At line 9, the symbolic execution continues to call $m_{\\text{post}}$ using $\\langle \\omega_m \\cdot \\gamma, \\omega_m \\cdot \\Gamma, \\phi \\rangle$ as an initial concolic state. Again line 10 cannot be true; otherwise Concolic_CCUJ returns false. So, by Lemma 2, from $\\langle \\alpha \\cdot m_{\\text{post}}, \\langle \\omega_m \\cdot \\gamma, \\omega_m \\cdot \\Gamma, \\phi \\rangle \\rangle \\rightarrow^* \\langle \\text{true}, \\omega_{\\text{post}} \\rangle$ we have $\\langle \\alpha \\cdot m_{\\text{post}}, \\sigma(\\omega_m \\cdot \\Gamma) \\rangle \\rightarrow^* \\langle \\sigma(\\text{true}), \\sigma(\\omega_{\\text{post}} \\cdot \\Gamma) \\rangle$. Using the transitive property of $\\rightarrow$ and lemma 2, for any $\\sigma$ such that $\\sigma$ satisfies $\\omega_m \\cdot C$ and $\\omega_{\\text{post}} \\cdot C$, we have $\\text{Pre}(\\sigma) \\Rightarrow \\text{Method}(\\sigma) \\land \\text{Post}(\\sigma)$ holds at line 13. Since there is no change $\\text{Pre}(\\sigma)$, $\\text{Method}(\\sigma)$, $\\text{Post}(\\sigma)$ at line 13, we still have $\\text{Pre}(\\sigma) \\Rightarrow \\text{Method}(\\sigma) \\land \\text{Post}(\\sigma)$.\n\nAt line 14, there are two scenarios:\n\n1. if $\\omega_m \\cdot C \\Rightarrow \\omega_{\\text{post}} \\cdot C$ is not a tautology then there exists state $\\sigma$ such that $\\sigma$ satisfies $\\omega_m \\cdot C$ but not $\\omega_{\\text{post}} \\cdot C$; so we need to explore a different path in $m_{\\text{post}}$. Thus, Concolic_CCUJ tries to find a new_pc. Since there is no execution of methods $\\alpha \\cdot m$ and $\\alpha \\cdot m_{\\text{post}}$, $\\text{Pre}(\\sigma) \\Rightarrow \\text{Method}(\\sigma) \\land \\text{Post}(\\sigma)$ still holds at lines 14, and 15.\n\n2. If $\\omega_m \\cdot C \\Rightarrow \\omega_{\\text{post}} \\cdot C$ is a tautology, then for any state $\\sigma$ if $\\sigma$ satisfies $\\omega_m \\cdot C$ then $\\sigma$ satisfies $\\omega_{\\text{post}} \\cdot C$. By Lemma 3, for all these states have the same $\\omega_{\\text{post}} \\cdot C$. In this case, we need to explore a different path in $\\alpha \\cdot m$. Since there is no execution of methods $\\alpha \\cdot m$ and $\\alpha \\cdot m_{\\text{post}}$, $\\text{Pre}(\\sigma) \\Rightarrow \\text{Method}(\\sigma) \\land \\text{Post}(\\sigma)$ holding at line 13 still holds at line 16, 17, and 18.\n\nAt line 19, $S$ is updated to $\\text{Pre} \\land \\text{new_pc}$. There are two possibilities for new_pc. First, if new_pc is not false, then $S$ is satisfiable because method backtracking pops all the top elements whose path constraint combined with\nPre is not satisfiable. Since Pre is part of S, so any state s satisfies S, s should satisfy Pre. If new_pc is false, then S is not satisfiable. Then, from the previous execution, we show for any state s we have Pre(s)⇒Method(s)∧Post(s). So the invariant holds at the end of the while statement.\n\nNext, if the while statement can terminate, namely, S is not satisfiable, then for any state s, Pre(s)⇒Method(s)∧Post(s) holds. We conclude the “only if” part proof.\n\nNext we prove the “if” part.\n\nAssume Concolic_CCUJ returns false if there exists a state s such that Pre(s)⇒Method(s)∧Post(s) holds. There are two scenarios that return false:\n\ni) If the condition is false at line 7, then <e’, ω_m> in <α·m, ω>→*<e’, ω_m> is an error heap configuration. By Lemma 2, <e’, ω_m, γ> is an error heap configuration and this contradicts the following fact: Pre(s)⇒Method(s)∧Post(s) where Method(s) is false. Otherwise, the condition is true at line 4. Then,\n\nii) If condition at line 10 is false and it means < α·m_post, < ω_m, γ, ω_m, Γ, φ >> →* <false, ω_post >. By Lemma 2, < s(α·m_post), s(ω_m, γ) > →* <s(false), s(ω_post) > holds and s(false)=false which contradicts the fact: Pre(s)⇒Method(s)∧Post(s) where Post(s) is false.\nThis concludes our proof.\n\n**Theorem 3:** Algorithm Concolic_CCUJ should terminate.\n\n**Proof:** To prove the termination of Algorithm Concolic_CCUJ, we need to prove that the while statement can terminate. By Theorem 1, we know $B$ includes a finite number of path constraints of $\\alpha .m;\\alpha .m_{post}$. Next, we will show that during each loop execution, a new path constraint according to new_pc is added to $B$. If this is true, then number of the execution of the while statement is equal to the number of elements in $B$.\n\nMethod backtracking is the only place to return a path condition. When method backtracking returns a path condition other than $false$, it must satisfy the following conditions:\n\n- $\\text{stack}_{-}pc[\\text{top}].\\text{flipped}=false$;\n- the path condition consisting of $\\text{stack}_{-}pc[1]\\land..\\land!\\text{stack}_{-}pc[\\text{top}]\\land\\text{Pre}$ is satisfiable;\n- $\\text{top}>0$\n\nAlso, a path constraint including path conditions $\\text{stack}_{-}pc[1],..,\\text{stack}_{-}pc[\\text{top}]$ is in $B$. In this case, we can guarantee that there are no path constraints in $B$ that have the path conditions $\\text{stack}_{-}pc[1],..,\\text{stack}_{-}pc[\\text{top}-1]$ and $!\\text{stack}_{-}pc[\\text{top}]$ as their prefix. To prove this, we assume there exists a path constraint in $B$ that has\nthe path conditions stack_pc[1],..., stack_pc[top-1] and !stack_pc[top] as its prefix.\n\nThen, stack_pc[top].flipped=true since another path constraint including path conditions stack_pc[1],...,stack_pc[top] has been in B. This contradicts the first condition which is stack_pc[top].flipped=false. So, the path constraint new_pc consisting of stack_pc[1]∧..∧!stack_pc[top] is not a prefix of any path constraint in B. Thus, the Concolic_CCUJ path constraints generated by new_pc is new in B.\nBIBLIOGRAPHY\n\n\n"}}},{"rowIdx":59,"cells":{"id":{"kind":"string","value":"816789d168359a8e810bdcc21915715a7b650ea2"},"text":{"kind":"string","value":"CBOR Object Signing and Encryption (COSE)\n\nAbstract\n\nConcise Binary Object Representation (CBOR) is a data format designed for small code size and small message size. There is a need for the ability to have basic security services defined for this data format. This document defines the CBOR Object Signing and Encryption (COSE) protocol. This specification describes how to create and process signatures, message authentication codes, and encryption using CBOR for serialization. This specification additionally describes how to represent cryptographic keys using CBOR.\n\nStatus of This Memo\n\nThis is an Internet Standards Track document.\n\nThis document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841.\n\nInformation about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc8152.\n\nCopyright Notice\n\nCopyright (c) 2017 IETF Trust and the persons identified as the document authors. All rights reserved.\n\nThis document is subject to BCP 78 and the IETF Trust’s Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.\nTable of Contents\n\n1. Introduction .......................................................... 4\n 1.1. Design Changes from JOSE ................................... 5\n 1.2. Requirements Terminology ................................... 6\n 1.3. CBOR Grammar ............................................. 6\n 1.4. CBOR-Related Terminology ................................ 7\n 1.5. Document Terminology ...................................... 8\n2. Basic COSE Structure ............................................... 8\n3. Header Parameters .................................................. 10\n 3.1. Common COSE Headers Parameters ........................... 12\n4. Signing Objects .................................................... 16\n 4.1. Signing with One or More Signers .......................... 16\n 4.2. Signing with One Signer ................................... 18\n 4.3. Externally Supplied Data .................................. 19\n 4.4. Signing and Verification Process .......................... 20\n 4.5. Computing Counter Signatures ............................. 22\n5. Encryption Objects ................................................ 22\n 5.1. Enveloped COSE Structure ................................... 23\n 5.1.1. Content Key Distribution Methods ................... 24\n 5.2. Single Recipient Encrypted ................................ 25\n 5.3. How to Encrypt and Decrypt for AEAD Algorithms ........... 26\n 5.4. How to Encrypt and Decrypt for AE Algorithms ............. 28\n6. MAC Objects .......................................................... 29\n 6.1. MACed Message with Recipients .............................. 30\n 6.2. MACed Messages with Implicit Key .......................... 31\n 6.3. How to Compute and Verify a MAC ........................... 32\n7. Key Objects .......................................................... 33\n 7.1. COSE Key Common Parameters ................................ 34\n8. Signature Algorithms .............................................. 37\n 8.1. ECDSA ..................................................... 38\n 8.1.1. Security Considerations ............................ 40\n 8.2. Edwards-Curve Digital Signature Algorithms (EdDSAs) ..... 40\n 8.2.1. Security Considerations ............................ 41\n 9.1. Hash-Based Message Authentication Codes (HMACs) ........... 42\n 9.1.1. Security Considerations ............................ 44\n 9.2. AES Message Authentication Code (AES-CBC-MAC) ........... 44\n 9.2.1. Security Considerations ............................ 45\n10. Content Encryption Algorithms .................................... 45\n 10.1. AES GCM .................................................. 46\n 10.1.1. Security Considerations ........................... 47\n 10.2. AES CCM .................................................. 47\n 10.2.1. Security Considerations ........................... 47\n 10.3. ChaCha20 and Poly1305 .................................... 50\n 10.3.1. Security Considerations ........................... 51\n11. Key Derivation Functions (KDFs) ................................ 51\n1. Introduction\n\nThere has been an increased focus on small, constrained devices that make up the Internet of Things (IoT). One of the standards that has come out of this process is \"Concise Binary Object Representation (CBOR)\" [RFC7049]. CBOR extended the data model of the JavaScript Object Notation (JSON) [RFC7159] by allowing for binary data, among other changes. CBOR is being adopted by several of the IETF working groups dealing with the IoT world as their encoding of data structures. CBOR was designed specifically to be both small in terms of messages transport and implementation size and be a schema-free decoder. A need exists to provide message security services for IoT, and using CBOR as the message-encoding format makes sense.\n\nThe JOSE working group produced a set of documents [RFC7515] [RFC7516] [RFC7517] [RFC7518] using JSON that specified how to process encryption, signatures, and Message Authentication Code (MAC) operations and how to encode keys using JSON. This document defines the CBOR Object Signing and Encryption (COSE) standard, which does the same thing for the CBOR encoding format. While there is a strong\nattempt to keep the flavor of the original JSON Object Signing and Encryption (JOSE) documents, two considerations are taken into account:\n\n- CBOR has capabilities that are not present in JSON and are appropriate to use. One example of this is the fact that CBOR has a method of encoding binary directly without first converting it into a base64-encoded string.\n\n- COSE is not a direct copy of the JOSE specification. In the process of creating COSE, decisions that were made for JOSE were re-examined. In many cases, different results were decided on as the criteria were not always the same.\n\n1.1. Design Changes from JOSE\n\n- Define a single top message structure so that encrypted, signed, and MACed messages can easily be identified and still have a consistent view.\n\n- Signed messages distinguish between the protected and unprotected parameters that relate to the content from those that relate to the signature.\n\n- MACed messages are separated from signed messages.\n\n- MACed messages have the ability to use the same set of recipient algorithms as enveloped messages for obtaining the MAC authentication key.\n\n- Use binary encodings for binary data rather than base64url encodings.\n\n- Combine the authentication tag for encryption algorithms with the ciphertext.\n\n- The set of cryptographic algorithms has been expanded in some directions and trimmed in others.\n1.2. Requirements Terminology\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"NOT RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.\n\nWhen the words appear in lowercase, this interpretation does not apply.\n\n1.3. CBOR Grammar\n\nThere is currently no standard CBOR grammar available for use by specifications. The CBOR structures are therefore described in prose.\n\nThe document was developed by first working on the grammar and then developing the prose to go with it. An artifact of this is that the prose was written using the primitive type strings defined by CBOR Data Definition Language (CDDL) [CDDL]. In this specification, the following primitive types are used:\n\n- **any** -- non-specific value that permits all CBOR values to be placed here.\n- **bool** -- a boolean value (true: major type 7, value 21; false: major type 7, value 20).\n- **bstr** -- byte string (major type 2).\n- **int** -- an unsigned integer or a negative integer.\n- **nil** -- a null value (major type 7, value 22).\n- **nint** -- a negative integer (major type 1).\n- **tstr** -- a UTF-8 text string (major type 3).\n- **uint** -- an unsigned integer (major type 0).\n\nTwo syntaxes from CDDL appear in this document as shorthand. These are:\n\n- **FOO / BAR** -- indicates that either FOO or BAR can appear here.\n- **[+ FOO]** -- indicates that the type FOO appears one or more times in an array.\nAs well as the prose description, a version of a CBOR grammar is presented in CDDL. Since CDDL has not been published in an RFC, this grammar may not work with the final version of CDDL. The CDDL grammar is informational; the prose description is normative.\n\nThe collected CDDL can be extracted from the XML version of this document via the following XPath expression below. (Depending on the XPath evaluator one is using, it may be necessary to deal with > as an entity.)\n\n```\n//artwork[@type='CDDL']/text()\n```\n\nCDDL expects the initial non-terminal symbol to be the first symbol in the file. For this reason, the first fragment of CDDL is presented here.\n\n```\nstart = COSE_Messages / COSE_Key / COSE_KeySet / Internal_Types\n\n; This is defined to make the tool quieter:\nInternal_Types = Sig_structure / Enc_structure / MAC_structure / COSE_KDF_Context\n```\n\nThe non-terminal Internal_Types is defined for dealing with the automated validation tools used during the writing of this document. It references those non-terminals that are used for security computations but are not emitted for transport.\n\n1.4. CBOR-Related Terminology\n\nIn JSON, maps are called objects and only have one kind of map key: a string. In COSE, we use strings, negative integers, and unsigned integers as map keys. The integers are used for compactness of encoding and easy comparison. The inclusion of strings allows for an additional range of short encoded values to be used as well. Since the word \"key\" is mainly used in its other meaning, as a cryptographic key, we use the term \"label\" for this usage as a map key.\n\nThe presence of a label in a COSE map that is not a string or an integer is an error. Applications can either fail processing or process messages with incorrect labels; however, they MUST NOT create messages with incorrect labels.\n\nA CDDL grammar fragment defines the non-terminal ‘label’, as in the previous paragraph, and ‘values’, which permits any value to be used.\n\n```\nlabel = int / tstr\nvalues = any\n```\n1.5. Document Terminology\n\nIn this document, we use the following terminology:\n\nByte is a synonym for octet.\n\nConstrained Application Protocol (CoAP) is a specialized web transfer protocol for use in constrained systems. It is defined in [RFC7252].\n\nAuthenticated Encryption (AE) [RFC5116] algorithms are those encryption algorithms that provide an authentication check of the contents algorithm with the encryption service.\n\nAuthenticated Encryption with Authenticated Data (AEAD) [RFC5116] algorithms provide the same content authentication service as AE algorithms, but they additionally provide for authentication of non-encrypted data as well.\n\n2. Basic COSE Structure\n\nThe COSE object structure is designed so that there can be a large amount of common code when parsing and processing the different types of security messages. All of the message structures are built on the CBOR array type. The first three elements of the array always contain the same information:\n\n1. The set of protected header parameters wrapped in a bstr.\n2. The set of unprotected header parameters as a map.\n3. The content of the message. The content is either the plaintext or the ciphertext as appropriate. The content may be detached, but the location is still used. The content is wrapped in a bstr when present and is a nil value when detached.\n\nElements after this point are dependent on the specific message type.\n\nCOSE messages are also built using the concept of layers to separate different types of cryptographic concepts. As an example of how this works, consider the COSE_Encrypt message (Section 5.1). This message type is broken into two layers: the content layer and the recipient layer. In the content layer, the plaintext is encrypted and information about the encrypted message is placed. In the recipient layer, the content encryption key (CEK) is encrypted and information about how it is encrypted for each recipient is placed. A single layer version of the encryption message COSE_Encrypt0 (Section 5.2) is provided for cases where the CEK is pre-shared.\nIdentification of which type of message has been presented is done by the following methods:\n\n1. The specific message type is known from the context. This may be defined by a marker in the containing structure or by restrictions specified by the application protocol.\n\n2. The message type is identified by a CBOR tag. Messages with a CBOR tag are known in this specification as tagged messages, while those without the CBOR tag are known as untagged messages. This document defines a CBOR tag for each of the message structures. These tags can be found in Table 1.\n\n3. When a COSE object is carried in a media type of ‘application/cose’, the optional parameter ‘cose-type’ can be used to identify the embedded object. The parameter is OPTIONAL if the tagged version of the structure is used. The parameter is REQUIRED if the untagged version of the structure is used. The value to use with the parameter for each of the structures can be found in Table 1.\n\n4. When a COSE object is carried as a CoAP payload, the CoAP Content-Format Option can be used to identify the message content. The CoAP Content-Format values can be found in Table 26. The CBOR tag for the message structure is not required as each security message is uniquely identified.\n\n<table>\n<thead>\n<tr>\n<th>CBOR Tag</th>\n<th>cose-type</th>\n<th>Data Item</th>\n<th>Semantics</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>98</td>\n<td>cose-sign</td>\n<td>COSE_Sign</td>\n<td>COSE Signed Data Object</td>\n</tr>\n<tr>\n<td>18</td>\n<td>cose-sign1</td>\n<td>COSE_Sign1</td>\n<td>COSE Single Signer Data Object</td>\n</tr>\n<tr>\n<td>96</td>\n<td>cose-encrypt</td>\n<td>COSE_Encrypt</td>\n<td>COSE Encrypted Data Object</td>\n</tr>\n<tr>\n<td>16</td>\n<td>cose-encrypt0</td>\n<td>COSE_Encrypt0</td>\n<td>COSE Single Recipient Encrypted Data Object</td>\n</tr>\n<tr>\n<td>97</td>\n<td>cose-mac</td>\n<td>COSE_Mac</td>\n<td>COSE MACed Data Object</td>\n</tr>\n<tr>\n<td>17</td>\n<td>cose-mac0</td>\n<td>COSE_Mac0</td>\n<td>COSE Mac w/o Recipients Object</td>\n</tr>\n</tbody>\n</table>\n\nTable 1: COSE Message Identification\nThe following CDDL fragment identifies all of the top messages defined in this document. Separate non-terminals are defined for the tagged and the untagged versions of the messages.\n\nCOSE_Messages = COSE_Untagged_Message / COSE_Tagged_Message\n\nCOSE_Untagged_Message = COSE_Sign / COSE_Sign1 / COSE_Encrypt / COSE_Encrypt0 / COSE_Mac / COSE_Mac0\n\nCOSE_Tagged_Message = COSE_Sign_Tagged / COSE_Sign1_Tagged / COSE_Encrypt_Tagged / COSE_Encrypt0_Tagged / COSE_Mac_Tagged / COSE_Mac0_Tagged\n\n3. Header Parameters\n\nThe structure of COSE has been designed to have two buckets of information that are not considered to be part of the payload itself, but are used for holding information about content, algorithms, keys, or evaluation hints for the processing of the layer. These two buckets are available for use in all of the structures except for keys. While these buckets are present, they may not all be usable in all instances. For example, while the protected bucket is defined as part of the recipient structure, some of the algorithms used for recipient structures do not provide for authenticated data. If this is the case, the protected bucket is left empty.\n\nBoth buckets are implemented as CBOR maps. The map key is a ‘label’ (Section 1.4). The value portion is dependent on the definition for the label. Both maps use the same set of label/value pairs. The integer and string values for labels have been divided into several sections including a standard range, a private range, and a range that is dependent on the algorithm selected. The defined labels can be found in the \"COSE Header Parameters\" IANA registry (Section 16.2).\n\nTwo buckets are provided for each layer:\n\nprotected: Contains parameters about the current layer that are to be cryptographically protected. This bucket MUST be empty if it is not going to be included in a cryptographic computation. This bucket is encoded in the message as a binary object. This value is obtained by CBOR encoding the protected map and wrapping it in a bstr object. Senders SHOULD encode a zero-length map as a zero-length string rather than as a zero-length map (encoded as h’a0’). The zero-length binary encoding is preferred because it is both shorter and the version used in the serialization structures for cryptographic computation. After encoding the map, the value is\nwrapped in the binary object. Recipients MUST accept both a zero-length binary value and a zero-length map encoded in the binary value. The wrapping allows for the encoding of the protected map to be transported with a greater chance that it will not be altered in transit. (Badly behaved intermediates could decode and re-encode, but this will result in a failure to verify unless the re-encoded byte string is identical to the decoded byte string.) This avoids the problem of all parties needing to be able to do a common canonical encoding.\n\nunprotected: Contains parameters about the current layer that are not cryptographically protected.\n\nOnly parameters that deal with the current layer are to be placed at that layer. As an example of this, the parameter ‘content type’ describes the content of the message being carried in the message. As such, this parameter is placed only in the content layer and is not placed in the recipient or signature layers. In principle, one should be able to process any given layer without reference to any other layer. With the exception of the COSE_Sign structure, the only data that needs to cross layers is the cryptographic key.\n\nThe buckets are present in all of the security objects defined in this document. The fields in order are the ‘protected’ bucket (as a CBOR ‘bstr’ type) and then the ‘unprotected’ bucket (as a CBOR ‘map’ type). The presence of both buckets is required. The parameters that go into the buckets come from the IANA \"COSE Header Parameters\" registry (Section 16.2). Some common parameters are defined in the next section, but a number of parameters are defined throughout this document.\n\nLabels in each of the maps MUST be unique. When processing messages, if a label appears multiple times, the message MUST be rejected as malformed. Applications SHOULD verify that the same label does not occur in both the protected and unprotected headers. If the message is not rejected as malformed, attributes MUST be obtained from the protected bucket before they are obtained from the unprotected bucket.\nThe following CDDL fragment represents the two header buckets. A group \"Headers\" is defined in CDDL that represents the two buckets in which attributes are placed. This group is used to provide these two fields consistently in all locations. A type is also defined that represents the map of common headers.\n\nHeaders = (\n protected : empty_or_serialized_map,\n unprotected : header_map\n)\n\nheader_map = {\n Generic_Headers,\n * label => values\n}\n\nempty_or_serialized_map = bstr .cbor header_map / bstr .size 0\n\n3.1. Common COSE Headers Parameters\n\nThis section defines a set of common header parameters. A summary of these parameters can be found in Table 2. This table should be consulted to determine the value of label and the type of the value.\n\nThe set of header parameters defined in this section are:\n\nalg: This parameter is used to indicate the algorithm used for the security processing. This parameter MUST be authenticated where the ability to do so exists. This support is provided by AEAD algorithms or construction (COSE_Sign, COSE_Sign0, COSE_Mac, and COSE_Mac0). This authentication can be done either by placing the header in the protected header bucket or as part of the externally supplied data. The value is taken from the \"COSE Algorithms\" registry (see Section 16.4).\n\ncrit: The parameter is used to indicate which protected header labels an application that is processing a message is required to understand. Parameters defined in this document do not need to be included as they should be understood by all implementations. When present, this parameter MUST be placed in the protected header bucket. The array MUST have at least one value in it. Not all labels need to be included in the ‘crit’ parameter. The rules for deciding which header labels are placed in the array are:\n\n* Integer labels in the range of 0 to 8 SHOULD be omitted.\n* Integer labels in the range -1 to -128 can be omitted as they are algorithm dependent. If an application can correctly process an algorithm, it can be assumed that it will correctly process all of the common parameters associated with that algorithm. Integer labels in the range -129 to -65536 SHOULD be included as these would be less common parameters that might not be generally supported.\n\n* Labels for parameters required for an application MAY be omitted. Applications should have a statement if the label can be omitted.\n\nThe header parameter values indicated by ‘crit’ can be processed by either the security library code or an application using a security library; the only requirement is that the parameter is processed. If the ‘crit’ value list includes a value for which the parameter is not in the protected bucket, this is a fatal error in processing the message.\n\nc-content type: This parameter is used to indicate the content type of the data in the payload or ciphertext fields. Integers are from the \"CoAP Content-Formats\" IANA registry table [COAP.Formats]. Text values following the syntax of \"<type-name>/<subtype-name>\" where <type-name> and <subtype-name> are defined in Section 4.2 of [RFC6838]. Leading and trailing whitespace is also omitted. Textual content values along with parameters and subparameters can be located using the IANA \"Media Types\" registry. Applications SHOULD provide this parameter if the content structure is potentially ambiguous.\n\nkid: This parameter identifies one piece of data that can be used as input to find the needed cryptographic key. The value of this parameter can be matched against the ‘kid’ member in a COSE_Key structure. Other methods of key distribution can define an equivalent field to be matched. Applications MUST NOT assume that ‘kid’ values are unique. There may be more than one key with the same ‘kid’ value, so all of the keys associated with this ‘kid’ may need to be checked. The internal structure of ‘kid’ values is not defined and cannot be relied on by applications. Key identifier values are hints about which key to use. This is not a security-critical field. For this reason, it can be placed in the unprotected headers bucket.\n\nIV: This parameter holds the Initialization Vector (IV) value. For some symmetric encryption algorithms, this may be referred to as a nonce. The IV can be placed in the unprotected header as modifying the IV will cause the decryption to yield plaintext that is readily detectable as garbled.\nPartial IV: This parameter holds a part of the IV value. When using the COSE_Encrypt0 structure, a portion of the IV can be part of the context associated with the key. This field is used to carry a value that causes the IV to be changed for each message. The IV can be placed in the unprotected header as modifying the IV will cause the decryption to yield plaintext that is readily detectable as garbled. The 'Initialization Vector' and 'Partial Initialization Vector' parameters MUST NOT both be present in the same security layer.\n\nThe message IV is generated by the following steps:\n\n1. Left-pad the Partial IV with zeros to the length of IV.\n2. XOR the padded Partial IV with the context IV.\n\ncounter signature: This parameter holds one or more counter signature values. Counter signatures provide a method of having a second party sign some data. The counter signature parameter can occur as an unprotected attribute in any of the following structures: COSE_Sign1, COSE_Signature, COSE_Encrypt, COSE_recipient, COSE_Encrypt0, COSE_Mac, and COSE_Mac0. These structures all have the same beginning elements, so that a consistent calculation of the counter signature can be computed. Details on computing counter signatures are found in Section 4.5.\nThe CDDL fragment that represents the set of headers defined in this section is given below. Each of the headers is tagged as optional because they do not need to be in every map; headers required in specific maps are discussed above.\n\n```\nGeneric_Headers = ( \n ? 1 => int / tstr, ; algorithm identifier \n ? 2 => [+label], ; criticality \n ? 3 => tstr / int, ; content type \n ? 4 => bstr, ; key identifier \n ? 5 => bstr, ; IV \n ? 6 => bstr, ; Partial IV \n ? 7 => COSE_Signature / [+COSE_Signature] ; Counter signature \n)\n```\n4. Signing Objects\n\nCOSE supports two different signature structures. COSE_Sign allows for one or more signatures to be applied to the same content. COSE_Sign1 is restricted to a single signer. The structures cannot be converted between each other; as the signature computation includes a parameter identifying which structure is being used, the converted structure will fail signature validation.\n\n4.1. Signing with One or More Signers\n\nThe COSE_Sign structure allows for one or more signatures to be applied to a message payload. Parameters relating to the content and parameters relating to the signature are carried along with the signature itself. These parameters may be authenticated by the signature, or just present. An example of a parameter about the content is the content type. Examples of parameters about the signature would be the algorithm and key used to create the signature and counter signatures.\n\nRFC 5652 indicates that:\n\nWhen more than one signature is present, the successful validation of one signature associated with a given signer is usually treated as a successful signature by that signer. However, there are some application environments where other rules are needed. An application that employs a rule other than one valid signature for each signer must specify those rules. Also, where simple matching of the signer identifier is not sufficient to determine whether the signatures were generated by the same signer, the application specification must describe how to determine which signatures were generated by the same signer. Support for different communities of recipients is the primary reason that signers choose to include more than one signature.\n\nFor example, the COSE_Sign structure might include signatures generated with the Edwards-curve Digital Signature Algorithm (EdDSA) [RFC8032] and with the Elliptic Curve Digital Signature Algorithm (ECDSA) [DSS]. This allows recipients to verify the signature associated with one algorithm or the other. More-detailed information on multiple signature evaluations can be found in [RFC5752].\nThe signature structure can be encoded as either tagged or untagged depending on the context it will be used in. A tagged COSE_Sign structure is identified by the CBOR tag 98. The CDDL fragment that represents this is:\n\n\\[\n\\text{COSE\\_Sign\\_Tagged} = \\#6.98(\\text{COSE\\_Sign})\n\\]\n\nA COSE Signed Message is defined in two parts. The CBOR object that carries the body and information about the body is called the COSE_Sign structure. The CBOR object that carries the signature and information about the signature is called the COSE_Signature structure. Examples of COSE Signed Messages can be found in Appendix C.1.\n\nThe COSE_Sign structure is a CBOR array. The fields of the array in order are:\n\n- protected: This is as described in Section 3.\n- unprotected: This is as described in Section 3.\n- payload: This field contains the serialized content to be signed. If the payload is not present in the message, the application is required to supply the payload separately. The payload is wrapped in a bstr to ensure that it is transported without changes. If the payload is transported separately (\"detached content\"), then a nil CBOR object is placed in this location, and it is the responsibility of the application to ensure that it will be transported without changes.\n\nNote: When a signature with a message recovery algorithm is used (Section 8), the maximum number of bytes that can be recovered is the length of the payload. The size of the payload is reduced by the number of bytes that will be recovered. If all of the bytes of the payload are consumed, then the payload is encoded as a zero-length binary string rather than as being absent.\n\n- signatures: This field is an array of signatures. Each signature is represented as a COSE_Signature structure.\n4.2. Signing with One Signer\n\nThe COSE_Sign1 signature structure is used when only one signature is going to be placed on a message. The parameters dealing with the content and the signature are placed in the same pair of buckets rather than having the separation of COSE_Sign.\n\nThe structure can be encoded as either tagged or untagged depending on the context it will be used in. A tagged COSE_Sign1 structure is identified by the CBOR tag 18. The CDDL fragment that represents this is:\n\nCOSE_Sign1_Tagged = #6.18(COSE_Sign1)\n\nThe CBOR object that carries the body, the signature, and the information about the body and signature is called the COSE_Sign1 structure. Examples of COSE_Sign1 messages can be found in Appendix C.2.\nThe COSE_Sign1 structure is a CBOR array. The fields of the array in order are:\n\nprotected: This is as described in Section 3.\n\nunprotected: This is as described in Section 3.\n\npayload: This is as described in Section 4.1.\n\nsignature: This field contains the computed signature value. The type of the field is a bstr.\n\nThe CDDL fragment that represents the above text for COSE_Sign1 follows.\n\nCOSE_Sign1 = [ Headers, payload : bstr / nil, signature : bstr ]\n\n4.3. Externally Supplied Data\n\nOne of the features offered in the COSE document is the ability for applications to provide additional data to be authenticated, but that is not carried as part of the COSE object. The primary reason for supporting this can be seen by looking at the CoAP message structure [RFC7252], where the facility exists for options to be carried before the payload. Examples of data that can be placed in this location would be the CoAP code or CoAP options. If the data is in the header section, then it is available for proxies to help in performing its operations. For example, the Accept Option can be used by a proxy to determine if an appropriate value is in the proxy’s cache. But the sender can prevent a proxy from changing the set of values that it will accept by including that value in the resulting authentication tag. However, it may also be desired to protect these values so that if they are modified in transit, it can be detected.\n\nThis document describes the process for using a byte array of externally supplied authenticated data; however, the method of constructing the byte array is a function of the application. Applications that use this feature need to define how the externally supplied authenticated data is to be constructed. Such a construction needs to take into account the following issues:\n\n- If multiple items are included, applications need to ensure that the same byte string is not produced if there are different inputs. This could occur by appending the strings ‘AB’ and ‘CDE’\nor by appending the strings ‘ABC’ and ‘DE’. This is usually addressed by making fields a fixed width and/or encoding the length of the field as part of the output. Using options from CoAP [RFC7252] as an example, these fields use a TLV structure so they can be concatenated without any problems.\n\n- If multiple items are included, an order for the items needs to be defined. Using options from CoAP as an example, an application could state that the fields are to be ordered by the option number.\n\n- Applications need to ensure that the byte stream is going to be the same on both sides. Using options from CoAP might give a problem if the same relative numbering is kept. An intermediate node could insert or remove an option, changing how the relative number is done. An application would need to specify that the relative number must be re-encoded to be relative only to the options that are in the external data.\n\n4.4. Signing and Verification Process\n\nIn order to create a signature, a well-defined byte stream is needed. The Sig_structure is used to create the canonical form. This signing and verification process takes in the body information (COSE_Sign or COSE_Sign1), the signer information (COSE_Signature), and the application data (external source). A Sig_structure is a CBOR array. The fields of the Sig_structure in order are:\n\n1. A text string identifying the context of the signature. The context string is:\n - \"Signature\" for signatures using the COSE_Signature structure.\n - \"Signature1\" for signatures using the COSE_Sign1 structure.\n - \"CounterSignature\" for signatures used as counter signature attributes.\n\n2. The protected attributes from the body structure encoded in a bstr type. If there are no protected attributes, a bstr of length zero is used.\n\n3. The protected attributes from the signer structure encoded in a bstr type. If there are no protected attributes, a bstr of length zero is used. This field is omitted for the COSE_Sign1 signature structure.\n4. The protected attributes from the application encoded in a bstr type. If this field is not supplied, it defaults to a zero-length binary string. (See Section 4.3 for application guidance on constructing this field.)\n\n5. The payload to be signed encoded in a bstr type. The payload is placed here independent of how it is transported.\n\nThe CDDL fragment that describes the above text is:\n\n```\nSig_structure = [\n context : \"Signature\" / \"Signature1\" / \"CounterSignature\",\n body_protected : empty_or_serialized_map,\n ? sign_protected : empty_or_serialized_map,\n external_aad : bstr,\n payload : bstr\n]\n```\n\nHow to compute a signature:\n\n1. Create a Sig_structure and populate it with the appropriate fields.\n\n2. Create the value ToBeSigned by encoding the Sig_structure to a byte string, using the encoding described in Section 14.\n\n3. Call the signature creation algorithm passing in K (the key to sign with), alg (the algorithm to sign with), and ToBeSigned (the value to sign).\n\n4. Place the resulting signature value in the ‘signature’ field of the array.\n\nThe steps for verifying a signature are:\n\n1. Create a Sig_structure object and populate it with the appropriate fields.\n\n2. Create the value ToBeSigned by encoding the Sig_structure to a byte string, using the encoding described in Section 14.\n\n3. Call the signature verification algorithm passing in K (the key to verify with), alg (the algorithm used sign with), ToBeSigned (the value to sign), and sig (the signature to be verified).\nIn addition to performing the signature verification, the application may also perform the appropriate checks to ensure that the key is correctly paired with the signing identity and that the signing identity is authorized before performing actions.\n\n4.5. Computing Counter Signatures\n\nCounter signatures provide a method of associating a different signature generated by different signers with some piece of content. This is normally used to provide a signature on a signature allowing for a proof that a signature existed at a given time (i.e., a Timestamp). In this document, we allow for counter signatures to exist in a greater number of environments. As an example, it is possible to place a counter signature in the unprotected attributes of a COSE_Encrypt object. This would allow for an intermediary to either verify that the encrypted byte stream has not been modified, without being able to decrypt it, or assert that an encrypted byte stream either existed at a given time or passed through it in terms of routing (i.e., a proxy signature).\n\nAn example of a counter signature on a signature can be found in Appendix C.1.3. An example of a counter signature in an encryption object can be found in Appendix C.3.3.\n\nThe creation and validation of counter signatures over the different items relies on the fact that the objects have the same structure. The elements are a set of protected attributes, a set of unprotected attributes, and a body, in that order. This means that the Sig_structure can be used in a uniform manner to get the byte stream for processing a signature. If the counter signature is going to be computed over a COSE_Encrypt structure, the body_protected and payload items can be mapped into the Sig_structure in the same manner as from the COSE_Sign structure.\n\nIt should be noted that only a signature algorithm with appendix (see Section 8) can be used for counter signatures. This is because the body should be able to be processed without having to evaluate the counter signature, and this is not possible for signature schemes with message recovery.\n\n5. Encryption Objects\n\nCOSE supports two different encryption structures. COSE_Encrypt0 is used when a recipient structure is not needed because the key to be used is known implicitly. COSE_Encrypt is used the rest of the time. This includes cases where there are multiple recipients or a recipient algorithm other than direct is used.\n5.1. Enveloped COSE Structure\n\nThe enveloped structure allows for one or more recipients of a message. There are provisions for parameters about the content and parameters about the recipient information to be carried in the message. The protected parameters associated with the content are authenticated by the content encryption algorithm. The protected parameters associated with the recipient are authenticated by the recipient algorithm (when the algorithm supports it). Examples of parameters about the content are the type of the content and the content encryption algorithm. Examples of parameters about the recipient are the recipient’s key identifier and the recipient’s encryption algorithm.\n\nThe same techniques and structures are used for encrypting both the plaintext and the keys. This is different from the approach used by both \"Cryptographic Message Syntax (CMS)\" [RFC5652] and \"JSON Web Encryption (JWE)\" [RFC7516] where different structures are used for the content layer and for the recipient layer. Two structures are defined: COSE_Encrypt to hold the encrypted content and COSE_recipient to hold the encrypted keys for recipients. Examples of encrypted messages can be found in Appendix C.3.\n\nThe COSE_Encrypt structure can be encoded as either tagged or untagged depending on the context it will be used in. A tagged COSE_Encrypt structure is identified by the CBOR tag 96. The CDDL fragment that represents this is:\n\n```cddl\nCOSE_Encrypt_Tagged = #6.96(COSE_Encrypt)\n```\n\nThe COSE_Encrypt structure is a CBOR array. The fields of the array in order are:\n\n- protected: This is as described in Section 3.\n- unprotected: This is as described in Section 3.\n- ciphertext: This field contains the ciphertext encoded as a bstr. If the ciphertext is to be transported independently of the control information about the encryption process (i.e., detached content), then the field is encoded as a nil value.\n- recipients: This field contains an array of recipient information structures. The type for the recipient information structure is a COSE_recipient.\nThe CDDL fragment that corresponds to the above text is:\n\n```\nCOSE_Encrypt = [\n Headers,\n ciphertext : bstr / nil,\n recipients : [+COSE_recipient]\n]\n```\n\nThe COSE_recipient structure is a CBOR array. The fields of the array in order are:\n\n- protected: This is as described in Section 3.\n- unprotected: This is as described in Section 3.\n- ciphertext: This field contains the encrypted key encoded as a bstr. All encoded keys are symmetric keys; the binary value of the key is the content. If there is not an encrypted key, then this field is encoded as a nil value.\n- recipients: This field contains an array of recipient information structures. The type for the recipient information structure is a COSE_recipient (an example of this can be found in Appendix B). If there are no recipient information structures, this element is absent.\n\nThe CDDL fragment that corresponds to the above text for COSE_recipient is:\n\n```\nCOSE_recipient = [\n Headers,\n ciphertext : bstr / nil,\n recipients : [+COSE_recipient]\n]\n```\n\n### 5.1.1. Content Key Distribution Methods\n\nAn encrypted message consists of an encrypted content and an encrypted CEK for one or more recipients. The CEK is encrypted for each recipient, using a key specific to that recipient. The details of this encryption depend on which class the recipient algorithm falls into. Specific details on each of the classes can be found in Section 12. A short summary of the five content key distribution methods is:\n\n- **direct**: The CEK is the same as the identified previously distributed symmetric key or is derived from a previously distributed secret. No CEK is transported in the message.\nsymmetric key-encryption keys (KEK): The CEK is encrypted using a\npreviously distributed symmetric KEK. Also known as key wrap.\n\nkey agreement: The recipient’s public key and a sender’s private key\nare used to generate a pairwise secret, a Key Derivation Function\n(KDF) is applied to derive a key, and then the CEK is either the\nderived key or encrypted by the derived key.\n\nkey transport: The CEK is encrypted with the recipient’s public key.\nNo key transport algorithms are defined in this document.\n\npasswords: The CEK is encrypted in a KEK that is derived from a\npassword. No password algorithms are defined in this document.\n\n5.2. Single Recipient Encrypted\n\nThe COSE_Encrypt0 encrypted structure does not have the ability to\nspecify recipients of the message. The structure assumes that the\nrecipient of the object will already know the identity of the key to\nbe used in order to decrypt the message. If a key needs to be\nidentified to the recipient, the enveloped structure ought to be\nused.\n\nExamples of encrypted messages can be found in Appendix C.3.\n\nThe COSE_Encrypt0 structure can be encoded as either tagged or\nuntagged depending on the context it will be used in. A tagged\nCOSE_Encrypt0 structure is identified by the CBOR tag 16. The CDDL\nfragment that represents this is:\n\nCOSE_Encrypt0_Tagged = #6.16(COSE_Encrypt0)\n\nThe COSE_Encrypt0 structure is a CBOR array. The fields of the array\nin order are:\n\nprotected: This is as described in Section 3.\n\nunprotected: This is as described in Section 3.\n\nciphertext: This is as described in Section 5.1.\n\nThe CDDL fragment for COSE_Encrypt0 that corresponds to the above\ntext is:\n\nCOSE_Encrypt0 = [\n Headers,\n ciphertext : bstr / nil,\n]\n5.3. How to Encrypt and Decrypt for AEAD Algorithms\n\nThe encryption algorithm for AEAD algorithms is fairly simple. The first step is to create a consistent byte stream for the authenticated data structure. For this purpose, we use an Enc_structure. The Enc_structure is a CBOR array. The fields of the Enc_structure in order are:\n\n1. A text string identifying the context of the authenticated data structure. The context string is:\n - \"Encrypt0\" for the content encryption of a COSE_Encrypt0 data structure.\n - \"Encrypt\" for the first layer of a COSE_Encrypt data structure (i.e., for content encryption).\n - \"Enc_Recipient\" for a recipient encoding to be placed in an COSE_Encrypt data structure.\n - \"Mac_Recipient\" for a recipient encoding to be placed in a MACed message structure.\n - \"Rec_Recipient\" for a recipient encoding to be placed in a recipient structure.\n\n2. The protected attributes from the body structure encoded in a bstr type. If there are no protected attributes, a bstr of length zero is used.\n\n3. The protected attributes from the application encoded in a bstr type. If this field is not supplied, it defaults to a zero-length bstr. (See Section 4.3 for application guidance on constructing this field.)\n\nThe CDDL fragment that describes the above text is:\n\n```\nEnc_structure = [ \n context : \"Encrypt\" / \"Encrypt0\" / \"Enc_Recipient\" / \"Mac_Recipient\" / \"Rec_Recipient\", \n protected : empty_or_serialized_map, \n external_aad : bstr \n]\n```\n\nHow to encrypt a message:\n\n1. Create an Enc_structure and populate it with the appropriate fields.\n2. Encode the Enc_structure to a byte stream (Additional Authenticated Data (AAD)), using the encoding described in Section 14.\n\n3. Determine the encryption key (K). This step is dependent on the class of recipient algorithm being used. For:\n\n No Recipients: The key to be used is determined by the algorithm and key at the current layer. Examples are key transport keys (Section 12.3), key wrap keys (Section 12.2.1), or pre-shared secrets.\n\n Direct Encryption and Direct Key Agreement: The key is determined by the key and algorithm in the recipient structure. The encryption algorithm and size of the key to be used are inputs into the KDF used for the recipient. (For direct, the KDF can be thought of as the identity operation.) Examples of these algorithms are found in Sections 12.1.2 and 12.4.1.\n\n Other: The key is randomly or pseudorandomly generated.\n\n4. Call the encryption algorithm with K (the encryption key), P (the plaintext), and AAD. Place the returned ciphertext into the ‘ciphertext’ field of the structure.\n\n5. For recipients of the message, recursively perform the encryption algorithm for that recipient, using K (the encryption key) as the plaintext.\n\nHow to decrypt a message:\n\n1. Create an Enc_structure and populate it with the appropriate fields.\n\n2. Encode the Enc_structure to a byte stream (AAD), using the encoding described in Section 14.\n\n3. Determine the decryption key. This step is dependent on the class of recipient algorithm being used. For:\n\n No Recipients: The key to be used is determined by the algorithm and key at the current layer. Examples are key transport keys (Section 12.3), key wrap keys (Section 12.2.1), or pre-shared secrets.\nDirect Encryption and Direct Key Agreement: The key is\ndetermined by the key and algorithm in the recipient\nstructure. The encryption algorithm and size of the key to be\nused are inputs into the KDF used for the recipient. (For\ndirect, the KDF can be thought of as the identity operation.)\nExamples of these algorithms are found in Sections 12.1.2 and\n12.4.1.\n\nOther: The key is determined by decoding and decrypting one of\nthe recipient structures.\n\n4. Call the decryption algorithm with K (the decryption key to use),\nC (the ciphertext), and AAD.\n\n5.4. How to Encrypt and Decrypt for AE Algorithms\n\nHow to encrypt a message:\n\n1. Verify that the ‘protected’ field is empty.\n\n2. Verify that there was no external additional authenticated data\n supplied for this operation.\n\n3. Determine the encryption key. This step is dependent on the\nclass of recipient algorithm being used. For:\n\n No Recipients: The key to be used is determined by the algorithm\n and key at the current layer. Examples are key transport keys\n (Section 12.3), key wrap keys (Section 12.2.1), or pre-shared\n secrets.\n\n Direct Encryption and Direct Key Agreement: The key is\ndetermined by the key and algorithm in the recipient\nstructure. The encryption algorithm and size of the key to be\nused are inputs into the KDF used for the recipient. (For\ndirect, the KDF can be thought of as the identity operation.)\nExamples of these algorithms are found in Sections 12.1.2 and\n12.4.1.\n\nOther: The key is randomly generated.\n\n4. Call the encryption algorithm with K (the encryption key to use)\nand P (the plaintext). Place the returned ciphertext into the\n‘ciphertext’ field of the structure.\n\n5. For recipients of the message, recursively perform the encryption\nalgorithm for that recipient, using K (the encryption key) as the\nplaintext.\nHow to decrypt a message:\n\n1. Verify that the ‘protected’ field is empty.\n\n2. Verify that there was no external additional authenticated data supplied for this operation.\n\n3. Determine the decryption key. This step is dependent on the class of recipient algorithm being used. For:\n\n No Recipients: The key to be used is determined by the algorithm and key at the current layer. Examples are key transport keys (Section 12.3), key wrap keys (Section 12.2.1), or pre-shared secrets.\n\n Direct Encryption and Direct Key Agreement: The key is determined by the key and algorithm in the recipient structure. The encryption algorithm and size of the key to be used are inputs into the KDF used for the recipient. (For direct, the KDF can be thought of as the identity operation.) Examples of these algorithms are found in Sections 12.1.2 and 12.4.1.\n\n Other: The key is determined by decoding and decrypting one of the recipient structures.\n\n4. Call the decryption algorithm with K (the decryption key to use) and C (the ciphertext).\n\n6. MAC Objects\n\nCOSE supports two different MAC structures. COSE_MAC0 is used when a recipient structure is not needed because the key to be used is implicitly known. COSE_MAC is used for all other cases. These include a requirement for multiple recipients, the key being unknown, and a recipient algorithm of other than direct.\n\nIn this section, we describe the structure and methods to be used when doing MAC authentication in COSE. This document allows for the use of all of the same classes of recipient algorithms as are allowed for encryption.\n\nWhen using MAC operations, there are two modes in which they can be used. The first is just a check that the content has not been changed since the MAC was computed. Any class of recipient algorithm can be used for this purpose. The second mode is to both check that the content has not been changed since the MAC was computed and to use the recipient algorithm to verify who sent it. The classes of\nrecipient algorithms that support this are those that use a pre-\nshared secret or do static-static (SS) key agreement (without the key\nwrap step). In both of these cases, the entity that created and sent\nthe message MAC can be validated. (This knowledge of the sender\nassumes that there are only two parties involved and that you did not\nsend the message to yourself.) The origination property can be\nobtained with both of the MAC message structures.\n\n6.1. MACed Message with Recipients\n\nThe multiple recipient MACed message uses two structures: the\nCOSE_Mac structure defined in this section for carrying the body and\nthe COSE_recipient structure (Section 5.1) to hold the key used for\nthe MAC computation. Examples of MACed messages can be found in\nAppendix C.5.\n\nThe MAC structure can be encoded as either tagged or untagged\ndepending on the context it will be used in. A tagged COSE_Mac\nstructure is identified by the CBOR tag 97. The CDDL fragment that\nrepresents this is:\n\nCOSE_Mac_Tagged = #6.97(COSE_Mac)\n\nThe COSE_Mac structure is a CBOR array. The fields of the array in\norder are:\n\nprotected: This is as described in Section 3.\n\nunprotected: This is as described in Section 3.\n\npayload: This field contains the serialized content to be MACed. If\nthe payload is not present in the message, the application is\nrequired to supply the payload separately. The payload is wrapped\nin a bstr to ensure that it is transported without changes. If\nthe payload is transported separately (i.e., detached content),\nthen a nil CBOR value is placed in this location, and it is the\nresponsibility of the application to ensure that it will be\ntransported without changes.\n\ntag: This field contains the MAC value.\n\nrecipients: This is as described in Section 5.1.\nThe CDDL fragment that represents the above text for COSE_Mac follows.\n\nCOSE_Mac = [\n Headers,\n payload : bstr / nil,\n tag : bstr,\n recipients :[+COSE_recipient]\n]\n\n6.2. MACed Messages with Implicit Key\n\nIn this section, we describe the structure and methods to be used when doing MAC authentication for those cases where the recipient is implicitly known.\n\nThe MACed message uses the COSE_Mac0 structure defined in this section for carrying the body. Examples of MACed messages with an implicit key can be found in Appendix C.6.\n\nThe MAC structure can be encoded as either tagged or untagged depending on the context it will be used in. A tagged COSE_Mac0 structure is identified by the CBOR tag 17. The CDDL fragment that represents this is:\n\nCOSE_Mac0_Tagged = #6.17(COSE_Mac0)\n\nThe COSE_Mac0 structure is a CBOR array. The fields of the array in order are:\n\nprotected: This is as described in Section 3.\n\nunprotected: This is as described in Section 3.\n\npayload: This is as described in Section 6.1.\n\ntag: This field contains the MAC value.\n\nThe CDDL fragment that corresponds to the above text is:\n\nCOSE_Mac0 = [\n Headers,\n payload : bstr / nil,\n tag : bstr,\n]\n6.3. How to Compute and Verify a MAC\n\nIn order to get a consistent encoding of the data to be authenticated, the MAC_structure is used to have a canonical form. The MAC_structure is a CBOR array. The fields of the MAC_structure in order are:\n\n1. A text string that identifies the structure that is being encoded. This string is \"MAC\" for the COSE_Mac structure. This string is \"MAC0\" for the COSE_Mac0 structure.\n\n2. The protected attributes from the COSE_MAC structure. If there are no protected attributes, a zero-length bstr is used.\n\n3. The protected attributes from the application encoded as a bstr type. If this field is not supplied, it defaults to a zero-length binary string. (See Section 4.3 for application guidance on constructing this field.)\n\n4. The payload to be MACed encoded in a bstr type. The payload is placed here independent of how it is transported.\n\nThe CDDL fragment that corresponds to the above text is:\n\nMAC_structure = [\n context : \"MAC\" / \"MAC0\",\n protected : empty_or_serialized_map,\n external_aad : bstr,\n payload : bstr\n]\n\nThe steps to compute a MAC are:\n\n1. Create a MAC_structure and populate it with the appropriate fields.\n\n2. Create the value ToBeMaced by encoding the MAC_structure to a byte stream, using the encoding described in Section 14.\n\n3. Call the MAC creation algorithm passing in K (the key to use), alg (the algorithm to MAC with), and ToBeMaced (the value to compute the MAC on).\n\n4. Place the resulting MAC in the 'tag' field of the COSE_Mac or COSE_Mac0 structure.\n\n5. Encrypt and encode the MAC key for each recipient of the message.\nThe steps to verify a MAC are:\n\n1. Create a MAC_structure object and populate it with the appropriate fields.\n\n2. Create the value ToBeMaced by encoding the MAC_structure to a byte stream, using the encoding described in Section 14.\n\n3. Obtain the cryptographic key from one of the recipients of the message.\n\n4. Call the MAC creation algorithm passing in K (the key to use), alg (the algorithm to MAC with), and ToBeMaced (the value to compute the MAC on).\n\n5. Compare the MAC value to the 'tag' field of the COSE_Mac or COSE_Mac0 structure.\n\n7. Key Objects\n\nA COSE Key structure is built on a CBOR map object. The set of common parameters that can appear in a COSE Key can be found in the IANA \"COSE Key Common Parameters\" registry (Section 16.5). Additional parameters defined for specific key types can be found in the IANA \"COSE Key Type Parameters\" registry (Section 16.6).\n\nA COSE Key Set uses a CBOR array object as its underlying type. The values of the array elements are COSE Keys. A COSE Key Set MUST have at least one element in the array. Examples of COSE Key Sets can be found in Appendix C.7.\n\nEach element in a COSE Key Set MUST be processed independently. If one element in a COSE Key Set is either malformed or uses a key that is not understood by an application, that key is ignored and the other keys are processed normally.\n\nThe element \"kty\" is a required element in a COSE_Key map.\nThe CDDL grammar describing COSE_Key and COSE_KeySet is:\n\n```\nCOSE_Key = {\n 1 => tstr / int, ; kty\n ? 2 => bstr, ; kid\n ? 3 => tstr / int, ; alg\n ? 4 => [+ (tstr / int) ], ; key_ops\n ? 5 => bstr, ; Base IV\n * label => values\n}\n```\n\nCOSE_KeySet = [+COSE_Key]\n\n### 7.1. COSE Key Common Parameters\n\nThis document defines a set of common parameters for a COSE Key object. Table 3 provides a summary of the parameters defined in this section. There are also parameters that are defined for specific key types. Key-type-specific parameters can be found in Section 13.\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Label</th>\n<th>CBOR Type</th>\n<th>Value Registry</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>kty</td>\n<td>1</td>\n<td>tstr / int</td>\n<td>COSE Key Common Parameters</td>\n<td>Identification of the key type</td>\n</tr>\n<tr>\n<td>kid</td>\n<td>2</td>\n<td>bstr</td>\n<td></td>\n<td>Key identification value -- match to kid in message</td>\n</tr>\n<tr>\n<td>alg</td>\n<td>3</td>\n<td>tstr / int</td>\n<td>COSE Algorithms</td>\n<td>Key usage restriction to this algorithm</td>\n</tr>\n<tr>\n<td>key_ops</td>\n<td>4</td>\n<td>[+ (tstr/int)]</td>\n<td></td>\n<td>Restrict set of permissible operations</td>\n</tr>\n<tr>\n<td>Base IV</td>\n<td>5</td>\n<td>bstr</td>\n<td></td>\n<td>Base IV to be xor-ed with Partial IVs</td>\n</tr>\n</tbody>\n</table>\n\nTable 3: Key Map Labels\n\n**kty**: This parameter is used to identify the family of keys for this structure and, thus, the set of key-type-specific parameters to be found. The set of values defined in this document can be found in Table 21. This parameter MUST be present in a key object. Implementations MUST verify that the key type is appropriate for the algorithm being processed. The key type MUST be included as part of the trust decision process.\n\n**alg**: This parameter is used to restrict the algorithm that is used with the key. If this parameter is present in the key structure, the application MUST verify that this algorithm matches the algorithm for which the key is being used. If the algorithms do not match, then this key object MUST NOT be used to perform the cryptographic operation. Note that the same key can be in a different key structure with a different or no algorithm specified; however, this is considered to be a poor security practice.\nkid: This parameter is used to give an identifier for a key. The identifier is not structured and can be anything from a user-provided string to a value computed on the public portion of the key. This field is intended for matching against a 'kid' parameter in a message in order to filter down the set of keys that need to be checked.\n\nkey_ops: This parameter is defined to restrict the set of operations that a key is to be used for. The value of the field is an array of values from Table 4. Algorithms define the values of key ops that are permitted to appear and are required for specific operations. The set of values matches that in [RFC7517] and [W3C.WebCrypto].\n\nBase IV: This parameter is defined to carry the base portion of an IV. It is designed to be used with the Partial IV header parameter defined in Section 3.1. This field provides the ability to associate a Partial IV with a key that is then modified on a per message basis with the Partial IV.\n\nExtreme care needs to be taken when using a Base IV in an application. Many encryption algorithms lose security if the same IV is used twice.\n\nIf different keys are derived for each sender, using the same Base IV with Partial IVs starting at zero is likely to ensure that the IV would not be used twice for a single key. If different keys are derived for each sender, starting at the same Base IV is likely to satisfy this condition. If the same key is used for multiple senders, then the application needs to provide for a method of dividing the IV space up between the senders. This could be done by providing a different base point to start from or a different Partial IV to start with and restricting the number of messages to be sent before rekeying.\n### Table 4: Key Operation Values\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>sign</td>\n<td>1</td>\n<td>The key is used to create signatures. Requires private key fields.</td>\n</tr>\n<tr>\n<td>verify</td>\n<td>2</td>\n<td>The key is used for verification of signatures.</td>\n</tr>\n<tr>\n<td>encrypt</td>\n<td>3</td>\n<td>The key is used for key transport encryption.</td>\n</tr>\n<tr>\n<td>decrypt</td>\n<td>4</td>\n<td>The key is used for key transport decryption.</td>\n</tr>\n<tr>\n<td>wrap</td>\n<td>5</td>\n<td>The key is used for key wrap encryption.</td>\n</tr>\n<tr>\n<td>key</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>unwrap</td>\n<td>6</td>\n<td>The key is used for key wrap decryption.</td>\n</tr>\n<tr>\n<td>key</td>\n<td></td>\n<td>Requires private key fields.</td>\n</tr>\n<tr>\n<td>derive</td>\n<td>7</td>\n<td>The key is used for deriving keys. Requires private key fields.</td>\n</tr>\n<tr>\n<td>key</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>derive</td>\n<td>8</td>\n<td>The key is used for deriving bits not to be used as a key. Requires private key fields.</td>\n</tr>\n<tr>\n<td>bits</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>MAC</td>\n<td>9</td>\n<td>The key is used for creating MACs.</td>\n</tr>\n<tr>\n<td>create</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>MAC</td>\n<td>10</td>\n<td>The key is used for validating MACs.</td>\n</tr>\n<tr>\n<td>verify</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n8. Signature Algorithms\n\nThere are two signature algorithm schemes. The first is signature with appendix. In this scheme, the message content is processed and a signature is produced; the signature is called the appendix. This is the scheme used by algorithms such as ECDSA and the RSA Probabilistic Signature Scheme (RSASSA-PSS). (In fact, the SSA in RSASSA-PSS stands for Signature Scheme with Appendix.)\n\nThe signature functions for this scheme are:\n\n\\[\n\\text{signature} = \\text{Sign}(\\text{message content, key})\n\\]\n\n\\[\n\\text{valid} = \\text{Verification}(\\text{message content, key, signature})\n\\]\n\nThe second scheme is signature with message recovery (an example of such an algorithm is [PVSig]). In this scheme, the message content is processed, but part of it is included in the signature. Moving bytes of the message content into the signature allows for smaller signatures; the signature size is still potentially large, but the message content has shrunk. This has implications for systems implementing these algorithms and for applications that use them. The first is that the message content is not fully available until\nafter a signature has been validated. Until that point, the part of the message contained inside of the signature is unrecoverable. The second is that the security analysis of the strength of the signature is very much based on the structure of the message content. Messages that are highly predictable require additional randomness to be supplied as part of the signature process. In the worst case, it becomes the same as doing a signature with appendix. Finally, in the event that multiple signatures are applied to a message, all of the signature algorithms are going to be required to consume the same number of bytes of message content. This means that the mixing of the different schemes in a single message is not supported, and if a recovery signature scheme is used, then the same amount of content needs to be consumed by all of the signatures.\n\nThe signature functions for this scheme are:\n\n\\[\n\\text{signature, message sent} = \\text{Sign}(\\text{message content}, \\text{key})\n\\]\n\n\\[\n\\text{valid, message content} = \\text{Verification}(\\text{message sent}, \\text{key}, \\text{signature})\n\\]\n\nSignature algorithms are used with the COSE_Signature and COSE_Sign1 structures. At this time, only signatures with appendixes are defined for use with COSE; however, considerable interest has been expressed in using a signature with message recovery algorithm due to the effective size reduction that is possible. Implementations will need to keep this in mind for later possible integration.\n\n8.1. ECDSA\n\nECDSA [DSS] defines a signature algorithm using ECC. Implementations SHOULD use a deterministic version of ECDSA such as the one defined in [RFC6979]. The use of a deterministic signature algorithm allows for systems to avoid relying on random number generators in order to avoid generating the same value of ‘k’ (the per-message random value). Biased generation of the value ‘k’ can be attacked, and collisions of this value leads to leaked keys. It additionally allows for doing deterministic tests for the signature algorithm. The use of deterministic ECDSA does not lessen the need to have good random number generation when creating the private key.\n\nThe ECDSA signature algorithm is parameterized with a hash function (h). In the event that the length of the hash function output is greater than the group of the key, the leftmost bytes of the hash output are used.\nThe algorithms defined in this document can be found in Table 5.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Hash</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ES256</td>\n<td>-7</td>\n<td>SHA-256</td>\n<td>ECDSA w/ SHA-256</td>\n</tr>\n<tr>\n<td>ES384</td>\n<td>-35</td>\n<td>SHA-384</td>\n<td>ECDSA w/ SHA-384</td>\n</tr>\n<tr>\n<td>ES512</td>\n<td>-36</td>\n<td>SHA-512</td>\n<td>ECDSA w/ SHA-512</td>\n</tr>\n</tbody>\n</table>\n\nTable 5: ECDSA Algorithm Values\n\nThis document defines ECDSA to work only with the curves P-256, P-384, and P-521. This document requires that the curves be encoded using the 'EC2' (2 coordinate elliptic curve) key type. Implementations need to check that the key type and curve are correct when creating and verifying a signature. Other documents can define it to work with other curves and points in the future.\n\nIn order to promote interoperability, it is suggested that SHA-256 be used only with curve P-256, SHA-384 be used only with curve P-384, and SHA-512 be used with curve P-521. This is aligned with the recommendation in Section 4 of [RFC5480].\n\nThe signature algorithm results in a pair of integers (R, S). These integers will be the same length as the length of the key used for the signature process. The signature is encoded by converting the integers into byte strings of the same length as the key size. The length is rounded up to the nearest byte and is left padded with zero bits to get to the correct length. The two integers are then concatenated together to form a byte string that is the resulting signature.\n\nUsing the function defined in [RFC8017], the signature is:\nSignature = I2OSP(R, n) | I2OSP(S, n)\nwhere n = ceiling(key_length / 8)\n\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The 'kty' field MUST be present, and it MUST be ‘EC2’.\n- If the 'alg' field is present, it MUST match the ECDSA signature algorithm being used.\n- If the 'key_ops' field is present, it MUST include ‘sign’ when creating an ECDSA signature.\nIf the 'key_ops' field is present, it MUST include 'verify' when verifying an ECDSA signature.\n\n8.1.1. Security Considerations\n\nThe security strength of the signature is no greater than the minimum of the security strength associated with the bit length of the key and the security strength of the hash function.\n\nNote: Use of this technique is a good idea even when good random number generation exists. Doing so both reduces the possibility of having the same value of 'k' in two signature operations and allows for reproducible signature values, which helps testing.\n\nThere are two substitution attacks that can theoretically be mounted against the ECDSA signature algorithm.\n\n- Changing the curve used to validate the signature: If one changes the curve used to validate the signature, then potentially one could have two messages with the same signature, each computed under a different curve. The only requirement on the new curve is that its order be the same as the old one and it be acceptable to the client. An example would be to change from using the curve secp256r1 (aka P-256) to using secp256k1. (Both are 256-bit curves.) We currently do not have any way to deal with this version of the attack except to restrict the overall set of curves that can be used.\n\n- Change the hash function used to validate the signature: If one either has two different hash functions of the same length or can truncate a hash function down, then one could potentially find collisions between the hash functions rather than within a single hash function (for example, truncating SHA-512 to 256 bits might collide with a SHA-256 bit hash value). As the hash algorithm is part of the signature algorithm identifier, this attack is mitigated by including a signature algorithm identifier in the protected header.\n\n8.2. Edwards-Curve Digital Signature Algorithms (EdDSAs)\n\n[RFC8032] describes the elliptic curve signature scheme Edwards-curve Digital Signature Algorithm (EdDSA). In that document, the signature algorithm is instantiated using parameters for edwards25519 and edwards448 curves. The document additionally describes two variants of the EdDSA algorithm: Pure EdDSA, where no hash function is applied to the content before signing, and HashEdDSA, where a hash function is applied to the content before signing and the result of that hash function is signed. For EdDSA, the content to be signed (either the\nmessage or the pre-hash value) is processed twice inside of the\nsignature algorithm. For use with COSE, only the pure EdDSA version\nis used. This is because it is not expected that extremely large\ncontents are going to be needed and, based on the arrangement of the\nmessage structure, the entire message is going to need to be held in\nmemory in order to create or verify a signature. This means that\nthere does not appear to be a need to be able to do block updates of\nthe hash, followed by eliminating the message from memory.\nApplications can provide the same features by defining the content of\nthe message as a hash value and transporting the COSE object (with\nthe hash value) and the content as separate items.\n\nThe algorithms defined in this document can be found in Table 6. A\nsingle signature algorithm is defined, which can be used for multiple\ncurves.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EdDSA</td>\n<td>-8</td>\n<td>EdDSA</td>\n</tr>\n</tbody>\n</table>\n\nTable 6: EdDSA Algorithm Values\n\n[RFC8032] describes the method of encoding the signature value.\n\nWhen using a COSE key for this algorithm, the following checks are\nmade:\n\n- The ‘kty’ field MUST be present, and it MUST be ‘OKP’ (Octet Key\n Pair).\n- The ‘crv’ field MUST be present, and it MUST be a curve defined\n for this signature algorithm.\n- If the ‘alg’ field is present, it MUST match ‘EdDSA’.\n- If the ‘key_ops’ field is present, it MUST include ‘sign’ when\n creating an EdDSA signature.\n- If the ‘key_ops’ field is present, it MUST include ‘verify’ when\n verifying an EdDSA signature.\n\n8.2.1. Security Considerations\n\nHow public values are computed is not the same when looking at EdDSA\nand Elliptic Curve Diffie-Hellman (ECDH); for this reason, they\nshould not be used with the other algorithm.\nIf batch signature verification is performed, a well-seeded cryptographic random number generator is REQUIRED. Signing and non-batch signature verification are deterministic operations and do not need random numbers of any kind.\n\n\nMessage Authentication Codes (MACs) provide data authentication and integrity protection. They provide either no or very limited data origination. A MAC, for example, can be used to prove the identity of the sender to a third party.\n\nMACs use the same scheme as signature with appendix algorithms. The message content is processed and an authentication code is produced. The authentication code is frequently called a tag.\n\nThe MAC functions are:\n\n\\[\ntag = \\text{MAC\\_Create}(\\text{message content}, \\text{key})\\]\n\n\\[\n\\text{valid} = \\text{MAC\\_Verify}(\\text{message content}, \\text{key}, \\text{tag})\\]\n\nMAC algorithms can be based on either a block cipher algorithm (i.e., AES-MAC) or a hash algorithm (i.e., a Hash-based Message Authentication Code (HMAC)). This document defines a MAC algorithm using each of these constructions.\n\nMAC algorithms are used in the COSE\\_Mac and COSE\\_Mac0 structures.\n\n9.1. Hash-Based Message Authentication Codes (HMACs)\n\nHMAC [RFC2104] [RFC4231] was designed to deal with length extension attacks. The algorithm was also designed to allow for new hash algorithms to be directly plugged in without changes to the hash function. The HMAC design process has been shown as solid since, while the security of hash algorithms such as MD5 has decreased over time; the security of HMAC combined with MD5 has not yet been shown to be compromised [RFC6151].\n\nThe HMAC algorithm is parameterized by an inner and outer padding, a hash function (h), and an authentication tag value length. For this specification, the inner and outer padding are fixed to the values set in [RFC2104]. The length of the authentication tag corresponds to the difficulty of producing a forgery. For use in constrained environments, we define a set of HMAC algorithms that are truncated.\nThere are currently no known issues with truncation; however, the security strength of the message tag is correspondingly reduced in strength. When truncating, the leftmost tag length bits are kept and transmitted.\n\nThe algorithms defined in this document can be found in Table 7.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Hash</th>\n<th>Tag Length</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>HMAC 256/64</td>\n<td>4</td>\n<td>SHA-256</td>\n<td>64</td>\n<td>HMAC w/ SHA-256 truncated to 64 bits</td>\n</tr>\n<tr>\n<td>HMAC 256/256</td>\n<td>5</td>\n<td>SHA-256</td>\n<td>256</td>\n<td>HMAC w/ SHA-256</td>\n</tr>\n<tr>\n<td>HMAC 384/384</td>\n<td>6</td>\n<td>SHA-384</td>\n<td>384</td>\n<td>HMAC w/ SHA-384</td>\n</tr>\n<tr>\n<td>HMAC 512/512</td>\n<td>7</td>\n<td>SHA-512</td>\n<td>512</td>\n<td>HMAC w/ SHA-512</td>\n</tr>\n</tbody>\n</table>\n\nTable 7: HMAC Algorithm Values\n\nSome recipient algorithms carry the key while others derive a key from secret data. For those algorithms that carry the key (such as AES Key Wrap), the size of the HMAC key SHOULD be the same size as the underlying hash function. For those algorithms that derive the key (such as ECDH), the derived key MUST be the same size as the underlying hash function.\n\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The ‘kty’ field MUST be present, and it MUST be ‘Symmetric’.\n- If the ‘alg’ field is present, it MUST match the HMAC algorithm being used.\n- If the ‘key_ops’ field is present, it MUST include ‘MAC create’ when creating an HMAC authentication tag.\n- If the ‘key_ops’ field is present, it MUST include ‘MAC verify’ when verifying an HMAC authentication tag.\n\nImplementations creating and validating MAC values MUST validate that the key type, key length, and algorithm are correct and appropriate for the entities involved.\n9.1.1. Security Considerations\n\nHMAC has proved to be resistant to attack even when used with weakened hash algorithms. The current best known attack is to brute force the key. This means that key size is going to be directly related to the security of an HMAC operation.\n\n9.2. AES Message Authentication Code (AES-CBC-MAC)\n\nAES-CBC-MAC is defined in [MAC]. (Note that this is not the same algorithm as AES Cipher-Based Message Authentication Code (AES-CMAC) [RFC4493].)\n\nAES-CBC-MAC is parameterized by the key length, the authentication tag length, and the IV used. For all of these algorithms, the IV is fixed to all zeros. We provide an array of algorithms for various key lengths and tag lengths. The algorithms defined in this document are found in Table 8.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Key Length</th>\n<th>Tag Length</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AES-MAC</td>\n<td>14</td>\n<td>128</td>\n<td>64</td>\n<td>AES-MAC 128-bit key, 64-bit tag</td>\n</tr>\n<tr>\n<td></td>\n<td>128/64</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>AES-MAC</td>\n<td>15</td>\n<td>256</td>\n<td>64</td>\n<td>AES-MAC 256-bit key, 64-bit tag</td>\n</tr>\n<tr>\n<td></td>\n<td>256/64</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>AES-MAC</td>\n<td>25</td>\n<td>128</td>\n<td>128</td>\n<td>AES-MAC 128-bit key, 128-bit tag</td>\n</tr>\n<tr>\n<td></td>\n<td>128/128</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>AES-MAC</td>\n<td>26</td>\n<td>256</td>\n<td>128</td>\n<td>AES-MAC 256-bit key, 128-bit tag</td>\n</tr>\n<tr>\n<td></td>\n<td>256/128</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nTable 8: AES-MAC Algorithm Values\n\nKeys may be obtained either from a key structure or from a recipient structure. Implementations creating and validating MAC values MUST validate that the key type, key length, and algorithm are correct and appropriate for the entities involved.\n\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The ’kty’ field MUST be present, and it MUST be ’Symmetric’.\n- If the ’alg’ field is present, it MUST match the AES-MAC algorithm being used.\nIf the 'key_ops' field is present, it MUST include 'MAC create' when creating an AES-MAC authentication tag.\n\nIf the 'key_ops' field is present, it MUST include 'MAC verify' when verifying an AES-MAC authentication tag.\n\n9.2.1. Security Considerations\n\nA number of attacks exist against Cipher Block Chaining Message Authentication Code (CBC-MAC) that need to be considered.\n\n- A single key must only be used for messages of a fixed and known length. If this is not the case, an attacker will be able to generate a message with a valid tag given two message and tag pairs. This can be addressed by using different keys for messages of different lengths. The current structure mitigates this problem, as a specific encoding structure that includes lengths is built and signed. (CMAC also addresses this issue.)\n\n- Cipher Block Chaining (CBC) mode, if the same key is used for both encryption and authentication operations, an attacker can produce messages with a valid authentication code.\n\n- If the IV can be modified, then messages can be forged. This is addressed by fixing the IV to all zeros.\n\n10. Content Encryption Algorithms\n\nContent encryption algorithms provide data confidentiality for potentially large blocks of data using a symmetric key. They provide integrity on the data that was encrypted; however, they provide either no or very limited data origination. (One cannot, for example, be used to prove the identity of the sender to a third party.) The ability to provide data origination is linked to how the CEK is obtained.\n\nCOSE restricts the set of legal content encryption algorithms to those that support authentication both of the content and additional data. The encryption process will generate some type of authentication value, but that value may be either explicit or implicit in terms of the algorithm definition. For simplicity’s sake, the authentication code will normally be defined as being appended to the ciphertext stream. The encryption functions are:\n\n\\[\n\\text{ciphertext} = \\text{Encrypt}(\\text{message content}, \\text{key}, \\text{additional data})\n\\]\n\n\\[\n\\text{valid, message content} = \\text{Decrypt}(\\text{cipher text}, \\text{key}, \\text{additional data})\n\\]\nMost AEAD algorithms are logically defined as returning the message content only if the decryption is valid. Many but not all implementations will follow this convention. The message content MUST NOT be used if the decryption does not validate.\n\nThese algorithms are used in COSE_Encrypt and COSE_Encrypt0.\n\n10.1. AES GCM\n\nThe Galois/Counter Mode (GCM) mode is a generic authenticated encryption block cipher mode defined in [AES-GCM]. The GCM mode is combined with the AES block encryption algorithm to define an AEAD cipher.\n\nThe GCM mode is parameterized by the size of the authentication tag and the size of the nonce. This document fixes the size of the nonce at 96 bits. The size of the authentication tag is limited to a small set of values. For this document however, the size of the authentication tag is fixed at 128 bits.\n\nThe set of algorithms defined in this document are in Table 9.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>A128GCM</td>\n<td>1</td>\n<td>AES-GCM mode w/ 128-bit key, 128-bit tag</td>\n</tr>\n<tr>\n<td>A192GCM</td>\n<td>2</td>\n<td>AES-GCM mode w/ 192-bit key, 128-bit tag</td>\n</tr>\n<tr>\n<td>A256GCM</td>\n<td>3</td>\n<td>AES-GCM mode w/ 256-bit key, 128-bit tag</td>\n</tr>\n</tbody>\n</table>\n\nTable 9: Algorithm Value for AES-GCM\n\nKeys may be obtained either from a key structure or from a recipient structure. Implementations encrypting and decrypting MUST validate that the key type, key length, and algorithm are correct and appropriate for the entities involved.\n\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The ’kty’ field MUST be present, and it MUST be ’Symmetric’.\n\n- If the ’alg’ field is present, it MUST match the AES-GCM algorithm being used.\n\n- If the ’key_ops’ field is present, it MUST include ’encrypt’ or ’wrap key’ when encrypting.\nIf the ‘key_ops’ field is present, it MUST include ‘decrypt’ or ‘unwrap key’ when decrypting.\n\n10.1.1. Security Considerations\n\nWhen using AES-GCM, the following restrictions MUST be enforced:\n\n- The key and nonce pair MUST be unique for every message encrypted.\n- The total amount of data encrypted for a single key MUST NOT exceed $2^{39} - 256$ bits. An explicit check is required only in environments where it is expected that it might be exceeded.\n\nConsideration was given to supporting smaller tag values; the constrained community would desire tag sizes in the 64-bit range. Doing so drastically changes both the maximum messages size (generally not an issue) and the number of times that a key can be used. Given that Counter with CBC-MAC (CCM) is the usual mode for constrained environments, restricted modes are not supported.\n\n10.2. AES CCM\n\nCCM is a generic authentication encryption block cipher mode defined in [RFC3610]. The CCM mode is combined with the AES block encryption algorithm to define a commonly used content encryption algorithm used in constrained devices.\n\nThe CCM mode has two parameter choices. The first choice is $M$, the size of the authentication field. The choice of the value for $M$ involves a trade-off between message growth (from the tag) and the probability that an attacker can undetectably modify a message. The second choice is $L$, the size of the length field. This value requires a trade-off between the maximum message size and the size of the Nonce.\n\nIt is unfortunate that the specification for CCM specified $L$ and $M$ as a count of bytes rather than a count of bits. This leads to possible misunderstandings where AES-CCM-8 is frequently used to refer to a version of CCM mode where the size of the authentication is 64 bits and not 8 bits. These values have traditionally been specified as bit counts rather than byte counts. This document will follow the convention of using bit counts so that it is easier to compare the different algorithms presented in this document.\n\nWe define a matrix of algorithms in this document over the values of $L$ and $M$. Constrained devices are usually operating in situations where they use short messages and want to avoid doing recipient-specific cryptographic operations. This favors smaller values of...\nboth L and M. Less-constrained devices will want to be able to use larger messages and are more willing to generate new keys for every operation. This favors larger values of L and M.\n\nThe following values are used for L:\n\n16 bits (2): This limits messages to $2^{16}$ bytes (64 KiB) in length. This is sufficiently long for messages in the constrained world. The nonce length is 13 bytes allowing for $2^{(13*8)}$ possible values of the nonce without repeating.\n\n64 bits (8): This limits messages to $2^{64}$ bytes in length. The nonce length is 7 bytes allowing for $2^{56}$ possible values of the nonce without repeating.\n\nThe following values are used for M:\n\n64 bits (8): This produces a 64-bit authentication tag. This implies that there is a 1 in $2^{64}$ chance that a modified message will authenticate.\n\n128 bits (16): This produces a 128-bit authentication tag. This implies that there is a 1 in $2^{128}$ chance that a modified message will authenticate.\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>L</th>\n<th>M</th>\n<th>k</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AES-CCM-16-64-128</td>\n<td>10</td>\n<td>16</td>\n<td>64</td>\n<td>128</td>\n<td>AES-CCM mode</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>128-bit key, 64-bit tag, 13-byte nonce</td>\n</tr>\n<tr>\n<td>AES-CCM-16-64-256</td>\n<td>11</td>\n<td>16</td>\n<td>64</td>\n<td>256</td>\n<td>AES-CCM mode</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>256-bit key, 64-bit tag, 13-byte nonce</td>\n</tr>\n<tr>\n<td>AES-CCM-64-64-128</td>\n<td>12</td>\n<td>64</td>\n<td>64</td>\n<td>128</td>\n<td>AES-CCM mode</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>128-bit key, 64-bit tag, 7-byte nonce</td>\n</tr>\n<tr>\n<td>AES-CCM-64-64-256</td>\n<td>13</td>\n<td>64</td>\n<td>64</td>\n<td>256</td>\n<td>AES-CCM mode</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>256-bit key, 64-bit tag, 7-byte nonce</td>\n</tr>\n<tr>\n<td>AES-CCM-16-128-128</td>\n<td>30</td>\n<td>16</td>\n<td>128</td>\n<td>128</td>\n<td>AES-CCM mode</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>128-bit key, 128-bit tag, 13-byte nonce</td>\n</tr>\n<tr>\n<td>AES-CCM-16-128-256</td>\n<td>31</td>\n<td>16</td>\n<td>128</td>\n<td>256</td>\n<td>AES-CCM mode</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>256-bit key, 128-bit tag, 13-byte nonce</td>\n</tr>\n<tr>\n<td>AES-CCM-64-128-128</td>\n<td>32</td>\n<td>64</td>\n<td>128</td>\n<td>128</td>\n<td>AES-CCM mode</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>128-bit key, 128-bit tag, 7-byte nonce</td>\n</tr>\n<tr>\n<td>AES-CCM-64-128-256</td>\n<td>33</td>\n<td>64</td>\n<td>128</td>\n<td>256</td>\n<td>AES-CCM mode</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>256-bit key, 128-bit tag, 7-byte nonce</td>\n</tr>\n</tbody>\n</table>\n\nTable 10: Algorithm Values for AES-CCM\n\nKeys may be obtained either from a key structure or from a recipient structure. Implementations encrypting and decrypting MUST validate that the key type, key length, and algorithm are correct and appropriate for the entities involved.\n\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The ‘kty’ field MUST be present, and it MUST be ‘Symmetric’.\n- If the ‘alg’ field is present, it MUST match the AES-CCM algorithm being used.\nIf the 'key_ops' field is present, it MUST include 'encrypt' or 'wrap key' when encrypting.\n\nIf the 'key_ops' field is present, it MUST include 'decrypt' or 'unwrap key' when decrypting.\n\n10.2.1. Security Considerations\n\nWhen using AES-CCM, the following restrictions MUST be enforced:\n\n- The key and nonce pair MUST be unique for every message encrypted. Note that the value of L influences the number of unique nonces.\n\n- The total number of times the AES block cipher is used MUST NOT exceed $2^{61}$ operations. This limitation is the sum of times the block cipher is used in computing the MAC value and in performing stream encryption operations. An explicit check is required only in environments where it is expected that it might be exceeded.\n\n[RFC3610] additionally calls out one other consideration of note. It is possible to do a pre-computation attack against the algorithm in cases where portions of the plaintext are highly predictable. This reduces the security of the key size by half. Ways to deal with this attack include adding a random portion to the nonce value and/or increasing the key size used. Using a portion of the nonce for a random value will decrease the number of messages that a single key can be used for. Increasing the key size may require more resources in the constrained device. See Sections 5 and 10 of [RFC3610] for more information.\n\n10.3. ChaCha20 and Poly1305\n\nChaCha20 and Poly1305 combined together is an AEAD mode that is defined in [RFC7539]. This is an algorithm defined to be a cipher that is not AES and thus would not suffer from any future weaknesses found in AES. These cryptographic functions are designed to be fast in software-only implementations.\n\nThe ChaCha20/Poly1305 AEAD construction defined in [RFC7539] has no parameterization. It takes a 256-bit key and a 96-bit nonce, as well as the plaintext and additional data as inputs and produces the ciphertext as an option. We define one algorithm identifier for this algorithm in Table 11.\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ChaCha20/Poly1305</td>\n<td>24</td>\n<td>ChaCha20/Poly1305 w/ 256-bit key,</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>128-bit tag</td>\n</tr>\n</tbody>\n</table>\n\nTable 11: Algorithm Value for AES-GCM\n\nKeys may be obtained either from a key structure or from a recipient structure. Implementations encrypting and decrypting MUST validate that the key type, key length, and algorithm are correct and appropriate for the entities involved.\n\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The 'kty' field MUST be present, and it MUST be 'Symmetric'.\n- If the 'alg' field is present, it MUST match the ChaCha20/Poly1305 algorithm being used.\n- If the 'key_ops' field is present, it MUST include 'encrypt' or 'wrap key' when encrypting.\n- If the 'key_ops' field is present, it MUST include 'decrypt' or 'unwrap key' when decrypting.\n\n10.3.1. Security Considerations\n\nThe key and nonce values MUST be a unique pair for every invocation of the algorithm. Nonce counters are considered to be an acceptable way of ensuring that they are unique.\n\n11. Key Derivation Functions (KDFs)\n\nKDFs are used to take some secret value and generate a different one. The secret value comes in three flavors:\n\n- Secrets that are uniformly random: This is the type of secret that is created by a good random number generator.\n- Secrets that are not uniformly random: This is type of secret that is created by operations like key agreement.\n- Secrets that are not random: This is the type of secret that people generate for things like passwords.\nGeneral KDFs work well with the first type of secret, can do reasonably well with the second type of secret, and generally do poorly with the last type of secret. None of the KDFs in this section are designed to deal with the type of secrets that are used for passwords. Functions like PBES2 [RFC8018] need to be used for that type of secret.\n\nThe same KDF can be set up to deal with the first two types of secrets in a different way. The KDF defined in Section 11.1 is such a function. This is reflected in the set of algorithms defined for the HMAC-based Extract-and-Expand Key Derivation Function (HKDF).\n\nWhen using KDFs, one component that is included is context information. Context information is used to allow for different keying information to be derived from the same secret. The use of context-based keying material is considered to be a good security practice.\n\nThis document defines a single context structure and a single KDF. These elements are used for all of the recipient algorithms defined in this document that require a KDF process. These algorithms are defined in Sections 12.1.2, 12.4.1, and 12.5.1.\n\n11.1. HMAC-Based Extract-and-Expand Key Derivation Function (HKDF)\n\nThe HKDF key derivation algorithm is defined in [RFC5869].\n\nThe HKDF algorithm takes these inputs:\n\n- secret -- a shared value that is secret. Secrets may be either previously shared or derived from operations like a Diffie-Hellman (DH) key agreement.\n\n- salt -- an optional value that is used to change the generation process. The salt value can be either public or private. If the salt is public and carried in the message, then the ‘salt’ algorithm header parameter defined in Table 13 is used. While [RFC5869] suggests that the length of the salt be the same as the length of the underlying hash value, any amount of salt will improve the security as different key values will be generated. This parameter is protected by being included in the key computation and does not need to be separately authenticated. The salt value does not need to be unique for every message sent.\n\n- length -- the number of bytes of output that need to be generated.\ncontext information -- Information that describes the context in which the resulting value will be used. Making this information specific to the context in which the material is going to be used ensures that the resulting material will always be tied to that usage. The context structure defined in Section 11.2 is used by the KDFs in this document.\n\nPRF -- The underlying pseudorandom function to be used in the HKDF algorithm. The PRF is encoded into the HKDF algorithm selection.\n\nHKDF is defined to use HMAC as the underlying PRF. However, it is possible to use other functions in the same construct to provide a different KDF that is more appropriate in the constrained world. Specifically, one can use AES-CBC-MAC as the PRF for the expand step, but not for the extract step. When using a good random shared secret of the correct length, the extract step can be skipped. For the AES algorithm versions, the extract step is always skipped.\n\nThe extract step cannot be skipped if the secret is not uniformly random, for example, if it is the result of an ECDH key agreement step. This implies that the AES HKDF version cannot be used with ECDH. If the extract step is skipped, the ‘salt’ value is not used as part of the HKDF functionality.\n\nThe algorithms defined in this document are found in Table 12.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>PRF</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>HKDF SHA-256</td>\n<td>HMAC with SHA-256</td>\n<td>HKDF using HMAC SHA-256 as the PRF</td>\n</tr>\n<tr>\n<td>HKDF SHA-512</td>\n<td>HMAC with SHA-512</td>\n<td>HKDF using HMAC SHA-512 as the PRF</td>\n</tr>\n<tr>\n<td>HKDF AES-MAC-128</td>\n<td>AES-CBC-MAC-128</td>\n<td>HKDF using AES-MAC as the PRF w/ 128-bit key</td>\n</tr>\n<tr>\n<td>HKDF AES-MAC-256</td>\n<td>AES-CBC-MAC-256</td>\n<td>HKDF using AES-MAC as the PRF w/ 256-bit key</td>\n</tr>\n</tbody>\n</table>\n\nTable 12: HKDF Algorithms\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Label</th>\n<th>Type</th>\n<th>Algorithm</th>\n<th>Description</th>\n</tr>\n</thead>\n</table>\n\nTable 13: HKDF Algorithm Parameters\n\n11.2. Context Information Structure\n\nThe context information structure is used to ensure that the derived keying material is \"bound\" to the context of the transaction. The context information structure used here is based on that defined in [SP800-56A]. By using CBOR for the encoding of the context information structure, we automatically get the same type and length separation of fields that is obtained by the use of ASN.1. This means that there is no need to encode the lengths for the base elements, as it is done by the encoding used in JOSE (Section 4.6.2 of [RFC7518]).\n\nThe context information structure refers to PartyU and PartyV as the two parties that are doing the key derivation. Unless the application protocol defines differently, we assign PartyU to the entity that is creating the message and PartyV to the entity that is receiving the message. By doing this association, different keys will be derived for each direction as the context information is different in each direction.\n\nThe context structure is built from information that is known to both entities. This information can be obtained from a variety of sources:\n\n- Fields can be defined by the application. This is commonly used to assign fixed names to parties, but it can be used for other items such as nonces.\n- Fields can be defined by usage of the output. Examples of this are the algorithm and key size that are being generated.\nFields can be defined by parameters from the message. We define a set of parameters in Table 14 that can be used to carry the values associated with the context structure. Examples of this are identities and nonce values. These parameters are designed to be placed in the unprotected bucket of the recipient structure; they do not need to be in the protected bucket since they already are included in the cryptographic computation by virtue of being included in the context structure.\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Label</th>\n<th>Type</th>\n<th>Algorithm</th>\n<th>Description</th>\n</tr>\n</thead>\n</table>\n\nSchaad Standards Track [Page 56]\n\nTable 14: Context Algorithm Parameters\nWe define a CBOR object to hold the context information. This object is referred to as COSE_KDF_Context. The object is based on a CBOR array type. The fields in the array are:\n\nAlgorithmID: This field indicates the algorithm for which the key material will be used. This normally is either a key wrap algorithm identifier or a content encryption algorithm identifier. The values are from the \"COSE Algorithms\" registry. This field is required to be present. The field exists in the context information so that if the same environment is used for different algorithms, then completely different keys will be generated for each of those algorithms. This practice means if algorithm A is broken and thus is easier to find, the key derived for algorithm B will not be the same as the key derived for algorithm A.\n\nPartyUIInfo: This field holds information about party U. The PartyUIInfo is encoded as a CBOR array. The elements of PartyUIInfo are encoded in the order presented. The elements of the PartyUIInfo array are:\n\nidentity: This contains the identity information for party U. The identities can be assigned in one of two manners. First, a protocol can assign identities based on roles. For example, the roles of \"client\" and \"server\" may be assigned to different entities in the protocol. Each entity would then use the correct label for the data they send or receive. The second way for a protocol to assign identities is to use a name based on a naming system (i.e., DNS, X.509 names).\n\nWe define an algorithm parameter 'PartyU identity' that can be used to carry identity information in the message. However, identity information is often known as part of the protocol and can thus be inferred rather than made explicit. If identity information is carried in the message, applications SHOULD have a way of validating the supplied identity information. The identity information does not need to be specified and is set to nil in that case.\n\nnonce: This contains a nonce value. The nonce can either be implicit from the protocol or be carried as a value in the unprotected headers.\n\nWe define an algorithm parameter 'PartyU nonce' that can be used to carry this value in the message; however, the nonce value could be determined by the application and the value determined from elsewhere.\nThis option does not need to be specified and is set to nil in that case.\n\nother: This contains other information that is defined by the protocol. This option does not need to be specified and is set to nil in that case.\n\nPartyVInfo: This field holds information about party V. The content of the structure is the same as for the PartyUInfo but for party V.\n\nSuppPubInfo: This field contains public information that is mutually known to both parties.\n\nkeyDataLength: This is set to the number of bits of the desired output value. This practice means if algorithm A can use two different key lengths, the key derived for longer key size will not contain the key for shorter key size as a prefix.\n\nprotected: This field contains the protected parameter field. If there are no elements in the protected field, then use a zero-length bstr.\n\nother: This field is for free form data defined by the application. An example is that an application could define two different strings to be placed here to generate different keys for a data stream versus a control stream. This field is optional and will only be present if the application defines a structure for this information. Applications that define this SHOULD use CBOR to encode the data so that types and lengths are correctly included.\n\nSuppPrivInfo: This field contains private information that is mutually known private information. An example of this information would be a preexisting shared secret. (This could, for example, be used in combination with an ECDH key agreement to provide a secondary proof of identity.) The field is optional and will only be present if the application defines a structure for this information. Applications that define this SHOULD use CBOR to encode the data so that types and lengths are correctly included.\nContent key distribution methods (recipient algorithms) can be defined into a number of different classes. COSE has the ability to support many classes of recipient algorithms. In this section, a number of classes are listed, and then a set of algorithms are specified for each of the classes. The names of the recipient algorithm classes used here are the same as those defined in [RFC7516]. Other specifications use different terms for the recipient algorithm classes or do not support some of the recipient algorithm classes.\n\n12.1. Direct Encryption\n\nThe direct encryption class algorithms share a secret between the sender and the recipient that is used either directly or after manipulation as the CEK. When direct encryption mode is used, it MUST be the only mode used on the message.\n\nThe COSE_Recipient structure for the recipient is organized as follows:\n\n- The ‘protected’ field MUST be a zero-length item unless it is used in the computation of the content key.\n- The ‘alg’ parameter MUST be present.\n- A parameter identifying the shared secret SHOULD be present.\nThe ‘ciphertext’ field MUST be a zero-length item.\n\nThe ‘recipients’ field MUST be absent.\n\n12.1.1. Direct Key\n\nThis recipient algorithm is the simplest; the identified key is directly used as the key for the next layer down in the message. There are no algorithm parameters defined for this algorithm. The algorithm identifier value is assigned in Table 15.\n\nWhen this algorithm is used, the protected field MUST be zero length. The key type MUST be ‘Symmetric’.\n\n```\n+--------+-------+-------------------+\n| Name | Value | Description |\n+--------+-------+-------------------+\n| direct | -6 | Direct use of CEK |\n+--------+-------+-------------------+\n```\n\nTable 15: Direct Key\n\n12.1.1.1. Security Considerations\n\nThis recipient algorithm has several potential problems that need to be considered:\n\n- These keys need to have some method to be regularly updated over time. All of the content encryption algorithms specified in this document have limits on how many times a key can be used without significant loss of security.\n\n- These keys need to be dedicated to a single algorithm. There have been a number of attacks developed over time when a single key is used for multiple different algorithms. One example of this is the use of a single key for both the CBC encryption mode and the CBC-MAC authentication mode.\n\n- Breaking one message means all messages are broken. If an adversary succeeds in determining the key for a single message, then the key for all messages is also determined.\n\n12.1.2. Direct Key with KDF\n\nThese recipient algorithms take a common shared secret between the two parties and applies the HKDF function (Section 11.1), using the context structure defined in Section 11.2 to transform the shared\nsecret into the CEK. The 'protected' field can be of non-zero length. Either the 'salt' parameter of HKDF or the 'PartyU nonce' parameter of the context structure MUST be present. The salt/nonce parameter can be generated either randomly or deterministically. The requirement is that it be a unique value for the shared secret in question.\n\nIf the salt/nonce value is generated randomly, then it is suggested that the length of the random value be the same length as the hash function underlying HKDF. While there is no way to guarantee that it will be unique, there is a high probability that it will be unique. If the salt/nonce value is generated deterministically, it can be guaranteed to be unique, and thus there is no length requirement.\n\nA new IV must be used for each message if the same key is used. The IV can be modified in a predictable manner, a random manner, or an unpredictable manner (i.e., encrypting a counter).\n\nThe IV used for a key can also be generated from the same HKDF functionality as the key is generated. If HKDF is used for generating the IV, the algorithm identifier is set to \"IV-GENERATION\".\n\nWhen these algorithms are used, the key type MUST be 'symmetric'.\n\nThe set of algorithms defined in this document can be found in Table 16.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>KDF</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>direct+HKDF-SHA-256</td>\n<td>-10</td>\n<td>HKDF</td>\n<td>Shared secret w/ HKDF</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>SHA-256</td>\n<td>and SHA-256</td>\n</tr>\n<tr>\n<td>direct+HKDF-SHA-512</td>\n<td>-11</td>\n<td>HKDF</td>\n<td>Shared secret w/ HKDF</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>SHA-512</td>\n<td>and SHA-512</td>\n</tr>\n<tr>\n<td>direct+HKDF-AES-128</td>\n<td>-12</td>\n<td>HKDF AES-</td>\n<td>Shared secret w/ AES-</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>MAC-128</td>\n<td>MAC 128-bit key</td>\n</tr>\n<tr>\n<td>direct+HKDF-AES-256</td>\n<td>-13</td>\n<td>HKDF AES-</td>\n<td>Shared secret w/ AES-</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>MAC-256</td>\n<td>MAC 256-bit key</td>\n</tr>\n</tbody>\n</table>\n\nTable 16: Direct Key with KDF\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The 'kty' field MUST be present, and it MUST be 'Symmetric'.\n- If the 'alg' field is present, it MUST match the algorithm being used.\n- If the 'key_ops' field is present, it MUST include 'deriveKey' or 'deriveBits'.\n\n### 12.1.2.1 Security Considerations\n\nThe shared secret needs to have some method to be regularly updated over time. The shared secret forms the basis of trust. Although not used directly, it should still be subject to scheduled rotation.\n\nWhile these methods do not provide for perfect forward secrecy, as the same shared secret is used for all of the keys generated, if the key for any single message is discovered, only the message (or series of messages) using that derived key are compromised. A new key derivation step will generate a new key that requires the same amount of work to get the key.\n\n### 12.2 Key Wrap\n\nIn key wrap mode, the CEK is randomly generated and that key is then encrypted by a shared secret between the sender and the recipient. All of the currently defined key wrap algorithms for COSE are AE algorithms. Key wrap mode is considered to be superior to direct encryption if the system has any capability for doing random key generation. This is because the shared key is used to wrap random data rather than data that has some degree of organization and may in fact be repeating the same content. The use of key wrap loses the weak data origination that is provided by the direct encryption algorithms.\n\nThe COSE_Encrypt structure for the recipient is organized as follows:\n\n- The 'protected' field MUST be absent if the key wrap algorithm is an AE algorithm.\n- The 'recipients' field is normally absent, but can be used. Applications MUST deal with a recipient field being present, not being able to decrypt that recipient is an acceptable way of dealing with it. Failing to process the message is not an acceptable way of dealing with it.\nThe plaintext to be encrypted is the key from next layer down (usually the content layer).\n\nAt a minimum, the ‘unprotected’ field MUST contain the ‘alg’ parameter and SHOULD contain a parameter identifying the shared secret.\n\n12.2.1. AES Key Wrap\n\nThe AES Key Wrap algorithm is defined in [RFC3394]. This algorithm uses an AES key to wrap a value that is a multiple of 64 bits. As such, it can be used to wrap a key for any of the content encryption algorithms defined in this document. The algorithm requires a single fixed parameter, the initial value. This is fixed to the value specified in Section 2.2.3.1 of [RFC3394]. There are no public parameters that vary on a per-invocation basis. The protected header field MUST be empty.\n\nKeys may be obtained either from a key structure or from a recipient structure. Implementations encrypting and decrypting MUST validate that the key type, key length, and algorithm are correct and appropriate for the entities involved.\n\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The ‘kty’ field MUST be present, and it MUST be ‘Symmetric’.\n- If the ‘alg’ field is present, it MUST match the AES Key Wrap algorithm being used.\n- If the ‘key_ops’ field is present, it MUST include ‘encrypt’ or ‘wrap key’ when encrypting.\n- If the ‘key_ops’ field is present, it MUST include ‘decrypt’ or ‘unwrap key’ when decrypting.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Key Size</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>A128KW</td>\n<td>-3</td>\n<td>128</td>\n<td>AES Key Wrap w/ 128-bit key</td>\n</tr>\n<tr>\n<td>A192KW</td>\n<td>-4</td>\n<td>192</td>\n<td>AES Key Wrap w/ 192-bit key</td>\n</tr>\n<tr>\n<td>A256KW</td>\n<td>-5</td>\n<td>256</td>\n<td>AES Key Wrap w/ 256-bit key</td>\n</tr>\n</tbody>\n</table>\n\nTable 17: AES Key Wrap Algorithm Values\n12.2.1.1. Security Considerations for AES-KW\n\nThe shared secret needs to have some method to be regularly updated over time. The shared secret is the basis of trust.\n\n12.3. Key Transport\n\nKey transport mode is also called key encryption mode in some standards. Key transport mode differs from key wrap mode in that it uses an asymmetric encryption algorithm rather than a symmetric encryption algorithm to protect the key. This document does not define any key transport mode algorithms.\n\nWhen using a key transport algorithm, the COSE_Encrypt structure for the recipient is organized as follows:\n\n- The ‘protected’ field MUST be absent.\n- The plaintext to be encrypted is the key from the next layer down (usually the content layer).\n- At a minimum, the ‘unprotected’ field MUST contain the ‘alg’ parameter and SHOULD contain a parameter identifying the asymmetric key.\n\n12.4. Direct Key Agreement\n\nThe ‘direct key agreement’ class of recipient algorithms uses a key agreement method to create a shared secret. A KDF is then applied to the shared secret to derive a key to be used in protecting the data. This key is normally used as a CEK or MAC key, but could be used for other purposes if more than two layers are in use (see Appendix B).\n\nThe most commonly used key agreement algorithm is Diffie-Hellman, but other variants exist. Since COSE is designed for a store and forward environment rather than an online environment, many of the DH variants cannot be used as the receiver of the message cannot provide any dynamic key material. One side effect of this is that perfect forward secrecy (see [RFC4949]) is not achievable. A static key will always be used for the receiver of the COSE object.\n\nTwo variants of DH that are supported are:\n\n- Ephemeral-Static (ES) DH: where the sender of the message creates a one-time DH key and uses a static key for the recipient. The use of the ephemeral sender key means that no additional random input is needed as this is randomly generated for each message.\nStatic-Static DH: where a static key is used for both the sender and the recipient. The use of static keys allows for the recipient to get a weak version of data origination for the message. When static-static key agreement is used, then some piece of unique data for the KDF is required to ensure that a different key is created for each message.\n\nWhen direct key agreement mode is used, there MUST be only one recipient in the message. This method creates the key directly, and that makes it difficult to mix with additional recipients. If multiple recipients are needed, then the version with key wrap needs to be used.\n\nThe COSE_Encrypt structure for the recipient is organized as follows:\n\n- At a minimum, headers MUST contain the ‘alg’ parameter and SHOULD contain a parameter identifying the recipient’s asymmetric key.\n- The headers SHOULD identify the sender’s key for the static-static versions and MUST contain the sender’s ephemeral key for the ephemeral-static versions.\n\n12.4.1. ECDH\n\nThe mathematics for ECDH can be found in [RFC6090]. In this document, the algorithm is extended to be used with the two curves defined in [RFC7748].\n\nECDH is parameterized by the following:\n\n- Curve Type/Curve: The curve selected controls not only the size of the shared secret, but the mathematics for computing the shared secret. The curve selected also controls how a point in the curve is represented and what happens for the identity points on the curve. In this specification, we allow for a number of different curves to be used. A set of curves are defined in Table 22. The math used to obtain the computed secret is based on the curve selected and not on the ECDH algorithm. For this reason, a new algorithm does not need to be defined for each of the curves.\n\n- Computed Secret to Shared Secret: Once the computed secret is known, the resulting value needs to be converted to a byte string to run the KDF. The x-coordinate is used for all of the curves defined in this document. For curves X25519 and X448, the resulting value is used directly as it is a byte string of a known length. For the P-256, P-384, and P-521 curves, the x-coordinate is run through the I2OSP function defined in [RFC8017], using the same computation for n as is defined in Section 8.1.\nEphemeral-Static or Static-Static: The key agreement process may be done using either a static or an ephemeral key for the sender’s side. When using ephemeral keys, the sender MUST generate a new ephemeral key for every key agreement operation. The ephemeral key is placed in the ‘ephemeral key’ parameter and MUST be present for all algorithm identifiers that use ephemeral keys. When using static keys, the sender MUST either generate a new random value or create a unique value. For the KDFs used, this means either the ‘salt’ parameter for HKDF (Table 13) or the ‘PartyU nonce’ parameter for the context structure (Table 14) MUST be present (both can be present if desired). The value in the parameter MUST be unique for the pair of keys being used. It is acceptable to use a global counter that is incremented for every static-static operation and use the resulting value. When using static keys, the static key should be identified to the recipient. The static key can be identified either by providing the key (‘static key’) or by providing a key identifier for the static key (‘static key id’). Both of these parameters are defined in Table 19.\n\nKey Derivation Algorithm: The result of an ECDH key agreement process does not provide a uniformly random secret. As such, it needs to be run through a KDF in order to produce a usable key. Processing the secret through a KDF also allows for the introduction of context material: how the key is going to be used and one-time material for static-static key agreement. All of the algorithms defined in this document use one of the HKDF algorithms defined in Section 11.1 with the context structure defined in Section 11.2.\n\nKey Wrap Algorithm: No key wrap algorithm is used. This is represented in Table 18 as ‘none’. The key size for the context structure is the content layer encryption algorithm size.\n\nThe set of direct ECDH algorithms defined in this document are found in Table 18.\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>KDF</th>\n<th>Ephemeral- Static</th>\n<th>Key Wrap</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ECDH-ES +</td>\n<td>-25</td>\n<td>HKDF -</td>\n<td>yes</td>\n<td>none</td>\n<td>ECDH ES w/ HKDF - generate key directly</td>\n</tr>\n<tr>\n<td>HKDF-256</td>\n<td></td>\n<td>SHA-256</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>ECDH-ES +</td>\n<td>-26</td>\n<td>HKDF -</td>\n<td>yes</td>\n<td>none</td>\n<td>ECDH ES w/ HKDF - generate key directly</td>\n</tr>\n<tr>\n<td>HKDF-512</td>\n<td></td>\n<td>SHA-512</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>ECDH-SS +</td>\n<td>-27</td>\n<td>HKDF -</td>\n<td>no</td>\n<td>none</td>\n<td>ECDH SS w/ HKDF - generate key directly</td>\n</tr>\n<tr>\n<td>HKDF-256</td>\n<td></td>\n<td>SHA-256</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>ECDH-SS +</td>\n<td>-28</td>\n<td>HKDF -</td>\n<td>no</td>\n<td>none</td>\n<td>ECDH SS w/ HKDF - generate key directly</td>\n</tr>\n<tr>\n<td>HKDF-512</td>\n<td></td>\n<td>SHA-512</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nTable 18: ECDH Algorithm Values\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Label</th>\n<th>Type</th>\n<th>Algorithm</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ephemeral key</td>\n<td>-1</td>\n<td>COSE_Key</td>\n<td>ECDH-ES+HKDF-256, ECDH-ES+HKDF-512, ECDH-ES+A128KW, ECDH-ES+A192KW, ECDH-ES+A256KW</td>\n<td>Ephemeral public key for the sender</td>\n</tr>\n<tr>\n<td>static key</td>\n<td>-2</td>\n<td>COSE_Key</td>\n<td>ECDH-SS+HKDF-256, ECDH-SS+HKDF-512, ECDH-SS+A128KW, ECDH-SS+A192KW, ECDH-SS+A256KW</td>\n<td>Static public key for the sender</td>\n</tr>\n<tr>\n<td>static key id</td>\n<td>-3</td>\n<td>bstr</td>\n<td>ECDH-SS+HKDF-256, ECDH-SS+HKDF-512, ECDH-SS+A128KW, ECDH-SS+A192KW, ECDH-SS+A256KW</td>\n<td>Static public key identifier for the sender</td>\n</tr>\n</tbody>\n</table>\n\nTable 19: ECDH Algorithm Parameters\nThis document defines these algorithms to be used with the curves P-256, P-384, P-521, X25519, and X448. Implementations MUST verify that the key type and curve are correct. Different curves are restricted to different key types. Implementations MUST verify that the curve and algorithm are appropriate for the entities involved.\n\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The 'kty' field MUST be present, and it MUST be 'EC2' or 'OKP'.\n- If the 'alg' field is present, it MUST match the key agreement algorithm being used.\n- If the 'key_ops' field is present, it MUST include 'derive key' or 'derive bits' for the private key.\n- If the 'key_ops' field is present, it MUST be empty for the public key.\n\n12.4.2. Security Considerations\n\nThere is a method of checking that points provided from external entities are valid. For the 'EC2' key format, this can be done by checking that the x and y values form a point on the curve. For the 'OKP' format, there is no simple way to do point validation.\n\nConsideration was given to requiring that the public keys of both entities be provided as part of the key derivation process (as recommended in Section 6.1 of [RFC7748]). This was not done as COSE is used in a store and forward format rather than in online key exchange. In order for this to be a problem, either the receiver public key has to be chosen maliciously or the sender has to be malicious. In either case, all security evaporates anyway.\n\nA proof of possession of the private key associated with the public key is recommended when a key is moved from untrusted to trusted (either by the end user or by the entity that is responsible for making trust statements on keys).\n\n12.5. Key Agreement with Key Wrap\n\nKey Agreement with Key Wrap uses a randomly generated CEK. The CEK is then encrypted using a key wrap algorithm and a key derived from the shared secret computed by the key agreement algorithm. The function for this would be:\n\n\\[ \\text{encryptedKey} = \\text{KeyWrap}(\\text{KDF(DH-Shared, context)}, \\text{CEK}) \\]\nThe COSE_Encrypt structure for the recipient is organized as follows:\n\n- The ‘protected’ field is fed into the KDF context structure.\n- The plaintext to be encrypted is the key from the next layer down (usually the content layer).\n- The ‘alg’ parameter MUST be present in the layer.\n- A parameter identifying the recipient’s key SHOULD be present. A parameter identifying the sender’s key SHOULD be present.\n\n12.5.1. ECDH\n\nThese algorithms are defined in Table 20.\n\nECDH with Key Agreement is parameterized by the same parameters as for ECDH; see Section 12.4.1, with the following modifications:\n\n- Key Wrap Algorithm: Any of the key wrap algorithms defined in Section 12.2.1 are supported. The size of the key used for the key wrap algorithm is fed into the KDF. The set of identifiers are found in Table 20.\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>KDF</th>\n<th>Ephemeral-Static</th>\n<th>Key Wrap</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ECDH-ES + A128KW</td>\n<td>-29</td>\n<td>HKDF - SHA-256</td>\n<td>yes</td>\n<td>A128KW</td>\n<td>ECDH ES w/ Concat KDF and AES Key Wrap w/ 128-bit key</td>\n</tr>\n<tr>\n<td>ECDH-ES + A192KW</td>\n<td>-30</td>\n<td>HKDF - SHA-256</td>\n<td>yes</td>\n<td>A192KW</td>\n<td>ECDH ES w/ Concat KDF and AES Key Wrap w/ 192-bit key</td>\n</tr>\n<tr>\n<td>ECDH-ES + A256KW</td>\n<td>-31</td>\n<td>HKDF - SHA-256</td>\n<td>yes</td>\n<td>A256KW</td>\n<td>ECDH ES w/ Concat KDF and AES Key Wrap w/ 256-bit key</td>\n</tr>\n<tr>\n<td>ECDH-SS + A128KW</td>\n<td>-32</td>\n<td>HKDF - SHA-256</td>\n<td>no</td>\n<td>A128KW</td>\n<td>ECDH SS w/ Concat KDF and AES Key Wrap w/ 128-bit key</td>\n</tr>\n<tr>\n<td>ECDH-SS + A192KW</td>\n<td>-33</td>\n<td>HKDF - SHA-256</td>\n<td>no</td>\n<td>A192KW</td>\n<td>ECDH SS w/ Concat KDF and AES Key Wrap w/ 192-bit key</td>\n</tr>\n<tr>\n<td>ECDH-SS + A256KW</td>\n<td>-34</td>\n<td>HKDF - SHA-256</td>\n<td>no</td>\n<td>A256KW</td>\n<td>ECDH SS w/ Concat KDF and AES Key Wrap w/ 256-bit key</td>\n</tr>\n</tbody>\n</table>\n\nTable 20: ECDH Algorithm Values with Key Wrap\nWhen using a COSE key for this algorithm, the following checks are made:\n\n- The 'kty' field MUST be present, and it MUST be 'EC2' or 'OKP'.\n- If the 'alg' field is present, it MUST match the key agreement algorithm being used.\n- If the 'key_ops' field is present, it MUST include 'derive key' or 'derive bits' for the private key.\n- If the 'key_ops' field is present, it MUST be empty for the public key.\n\n13. Key Object Parameters\n\nThe COSE_Key object defines a way to hold a single key object. It is still required that the members of individual key types be defined. This section of the document is where we define an initial set of members for specific key types.\n\nFor each of the key types, we define both public and private members. The public members are what is transmitted to others for their usage. Private members allow for the archival of keys by individuals. However, there are some circumstances in which private keys may be distributed to entities in a protocol. Examples include: entities that have poor random number generation, centralized key creation for multi-cast type operations, and protocols in which a shared secret is used as a bearer token for authorization purposes.\n\nKey types are identified by the 'kty' member of the COSE_Key object. In this document, we define four values for the member:\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>OKP</td>\n<td>1</td>\n<td>Octet Key Pair</td>\n</tr>\n<tr>\n<td>EC2</td>\n<td>2</td>\n<td>Elliptic Curve Keys w/ x- and y-coordinate pair</td>\n</tr>\n<tr>\n<td>Symmetric</td>\n<td>4</td>\n<td>Symmetric Keys</td>\n</tr>\n<tr>\n<td>Reserved</td>\n<td>0</td>\n<td>This value is reserved</td>\n</tr>\n</tbody>\n</table>\n\nTable 21: Key Type Values\n13.1. Elliptic Curve Keys\n\nTwo different key structures are defined for elliptic curve keys. One version uses both an x-coordinate and a y-coordinate, potentially with point compression (‘EC2’). This is the traditional EC point representation that is used in [RFC5480]. The other version uses only the x-coordinate as the y-coordinate is either to be recomputed or not needed for the key agreement operation (‘OKP’).\n\nApplications MUST check that the curve and the key type are consistent and reject a key if they are not.\n\n+---------+-------+----------+------------------------------------+\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Value</th>\n<th>Key Type</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>P-256</td>\n<td>1</td>\n<td>EC2</td>\n<td>NIST P-256 also known as secp256r1</td>\n</tr>\n<tr>\n<td>P-384</td>\n<td>2</td>\n<td>EC2</td>\n<td>NIST P-384 also known as secp384r1</td>\n</tr>\n<tr>\n<td>P-521</td>\n<td>3</td>\n<td>EC2</td>\n<td>NIST P-521 also known as secp521r1</td>\n</tr>\n<tr>\n<td>X25519</td>\n<td>4</td>\n<td>OKP</td>\n<td>X25519 for use w/ ECDH only</td>\n</tr>\n<tr>\n<td>X448</td>\n<td>5</td>\n<td>OKP</td>\n<td>X448 for use w/ ECDH only</td>\n</tr>\n<tr>\n<td>Ed25519</td>\n<td>6</td>\n<td>OKP</td>\n<td>Ed25519 for use w/ EdDSA only</td>\n</tr>\n<tr>\n<td>Ed448</td>\n<td>7</td>\n<td>OKP</td>\n<td>Ed448 for use w/ EdDSA only</td>\n</tr>\n</tbody>\n</table>\n+---------+-------+----------+------------------------------------+\n\nTable 22: Elliptic Curves\n\n13.1.1. Double Coordinate Curves\n\nThe traditional way of sending ECs has been to send either both the x-coordinate and y-coordinate or the x-coordinate and a sign bit for the y-coordinate. The latter encoding has not been recommended in the IETF due to potential IPR issues. However, for operations in constrained environments, the ability to shrink a message by not sending the y-coordinate is potentially useful.\n\nFor EC keys with both coordinates, the ‘kty’ member is set to 2 (EC2). The key parameters defined in this section are summarized in Table 23. The members that are defined for this key type are:\n\n- **crv**: This contains an identifier of the curve to be used with the key. The curves defined in this document for this key type can be found in Table 22. Other curves may be registered in the future, and private curves can be used as well.\n\n- **x**: This contains the x-coordinate for the EC point. The integer is converted to an octet string as defined in [SEC1]. Leading zero octets MUST be preserved.\ny: This contains either the sign bit or the value of the y-coordinate for the EC point. When encoding the value y, the integer is converted to an octet string (as defined in [SEC1]) and encoded as a CBOR bstr. Leading zero octets MUST be preserved. The compressed point encoding is also supported. Compute the sign bit as laid out in the Elliptic-Curve-Point-to-Octet-String Conversion function of [SEC1]. If the sign bit is zero, then encode y as a CBOR false value; otherwise, encode y as a CBOR true value. The encoding of the infinity point is not supported.\n\nd: This contains the private key.\n\nFor public keys, it is REQUIRED that ‘crv’, ‘x’, and ‘y’ be present in the structure. For private keys, it is REQUIRED that ‘crv’ and ‘d’ be present in the structure. For private keys, it is RECOMMENDED that ‘x’ and ‘y’ also be present, but they can be recomputed from the required elements and omitting them saves on space.\n\n<table>\n<thead>\n<tr>\n<th>Key Type</th>\n<th>Name</th>\n<th>Label</th>\n<th>CBOR Type</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2</td>\n<td>crv</td>\n<td>-1</td>\n<td>int / tstr</td>\n<td>EC identifier - Taken from the "COSE Elliptic Curves" registry</td>\n</tr>\n<tr>\n<td>2</td>\n<td>x</td>\n<td>-2</td>\n<td>bstr</td>\n<td>x-coordinate</td>\n</tr>\n<tr>\n<td>2</td>\n<td>y</td>\n<td>-3</td>\n<td>bstr / bool</td>\n<td>y-coordinate</td>\n</tr>\n<tr>\n<td>2</td>\n<td>d</td>\n<td>-4</td>\n<td>bstr</td>\n<td>Private key</td>\n</tr>\n</tbody>\n</table>\n\nTable 23: EC Key Parameters\n\n13.2. Octet Key Pair\n\nA new key type is defined for Octet Key Pairs (OKP). Do not assume that keys using this type are elliptic curves. This key type could be used for other curve types (for example, mathematics based on hyper-elliptic surfaces).\n\nThe key parameters defined in this section are summarized in Table 24. The members that are defined for this key type are:\n\ncrv: This contains an identifier of the curve to be used with the key. The curves defined in this document for this key type can be found in Table 22. Other curves may be registered in the future and private curves can be used as well.\nx: This contains the x-coordinate for the EC point. The octet string represents a little-endian encoding of x.\n\nd: This contains the private key.\n\nFor public keys, it is REQUIRED that ‘crv’ and ‘x’ be present in the structure. For private keys, it is REQUIRED that ‘crv’ and ‘d’ be present in the structure. For private keys, it is RECOMMENDED that ‘x’ also be present, but it can be recomputed from the required elements and omitting it saves on space.\n\n+-----------------+-------+-------+--------+-----------------------------------+\n| Name | Key | Label | Type | Description |\n| | Type | | | |\n+------+-------+-------+--------+-----------------------------------+\n| crv | 1 | -1 | int / | EC identifier - Taken from the |\n | | | tstr | \"COSE Key Common Parameters\" |\n | | | | registry |\n| x | 1 | -2 | bstr | x-coordinate |\n| d | 1 | -4 | bstr | Private key |\n+------+-------+-------+--------+-----------------------------------+\n\nTable 24: Octet Key Pair Parameters\n\n13.3. Symmetric Keys\n\nOccasionally it is required that a symmetric key be transported between entities. This key structure allows for that to happen.\n\nFor symmetric keys, the ‘kty’ member is set to 4 (‘Symmetric’). The member that is defined for this key type is:\n\nk: This contains the value of the key.\n\nThis key structure does not have a form that contains only public members. As it is expected that this key structure is going to be transmitted, care must be taken that it is never transmitted accidentally or insecurely. For symmetric keys, it is REQUIRED that ‘k’ be present in the structure.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Key Type</th>\n<th>Label</th>\n<th>Type</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>k</td>\n<td>4</td>\n<td>-1</td>\n<td>bstr</td>\n<td>Key Value</td>\n</tr>\n</tbody>\n</table>\n\nTable 25: Symmetric Key Parameters\n14. CBOR Encoder Restrictions\n\nThere has been an attempt to limit the number of places where the document needs to impose restrictions on how the CBOR Encoder needs to work. We have managed to narrow it down to the following restrictions:\n\n- The restriction applies to the encoding of the Sig_structure, the Enc_structure, and the MAC_structure.\n\n- The rules for \"Canonical CBOR\" (Section 3.9 of RFC 7049) MUST be used in these locations. The main rule that needs to be enforced is that all lengths in these structures MUST be encoded such that they are using definite lengths, and the minimum length encoding is used.\n\n- Applications MUST NOT generate messages with the same label used twice as a key in a single map. Applications MUST NOT parse and process messages with the same label used twice as a key in a single map. Applications can enforce the parse and process requirement by using parsers that will fail the parse step or by using parsers that will pass all keys to the application, and the application can perform the check for duplicate keys.\n\n15. Application Profiling Considerations\n\nThis document is designed to provide a set of security services, but not implementation requirements for specific usage. The interoperability requirements are provided for how each of the individual services are used and how the algorithms are to be used for interoperability. The requirements about which algorithms and which services are needed are deferred to each application.\n\nAn example of a profile can be found in [OSCOAP] where two profiles are being developed. One is for carrying content by itself, and the other is for carrying content in combination with CoAP headers.\n\nIt is intended that a profile of this document be created that defines the interoperability requirements for that specific application. This section provides a set of guidelines and topics that need to be considered when profiling this document.\n\n- Applications need to determine the set of messages defined in this document that they will be using. The set of messages corresponds fairly directly to the set of security services that are needed and to the security levels needed.\nApplications may define new header parameters for a specific purpose. Applications will often times select specific header parameters to use or not to use. For example, an application would normally state a preference for using either the IV or the Partial IV parameter. If the Partial IV parameter is specified, then the application would also need to define how the fixed portion of the IV would be determined.\n\nWhen applications use externally defined authenticated data, they need to define how that data is encoded. This document assumes that the data will be provided as a byte stream. More information can be found in Section 4.3.\n\nApplications need to determine the set of security algorithms that are to be used. When selecting the algorithms to be used as the mandatory-to-implement set, consideration should be given to choosing different types of algorithms when two are chosen for a specific purpose. An example of this would be choosing HMAC-SHA512 and AES-CMAC as different MAC algorithms; the construction is vastly different between these two algorithms. This means that a weakening of one algorithm would be unlikely to lead to a weakening of the other algorithms. Of course, these algorithms do not provide the same level of security and thus may not be comparable for the desired security functionality.\n\nApplications may need to provide some type of negotiation or discovery method if multiple algorithms or message structures are permitted. The method can be as simple as requiring preconfiguration of the set of algorithms to providing a discovery method built into the protocol. S/MIME provided a number of different ways to approach the problem that applications could follow:\n\n* Advertising in the message (S/MIME capabilities) [RFC5751].\n* Advertising in the certificate (capabilities extension) [RFC4262].\n* Minimum requirements for the S/MIME, which have been updated over time [RFC2633] [RFC5751] (note that [RFC2633] has been obsoleted by [RFC5751]).\n16. IANA Considerations\n\n16.1. CBOR Tag Assignment\n\nIANA has assigned the following tags from the \"CBOR Tags\" registry. The tags for COSE_Sign1, COSE_Encrypt0, and COSE_Mac0 were assigned in the 1 to 23 value range (one byte long when encoded). The tags for COSE_Sign, COSE_Encrypt, and COSE_Mac were assigned in the 24 to 255 value range (two bytes long when encoded).\n\nThe tags assigned are in Table 1.\n\n16.2. COSE Header Parameters Registry\n\nIANA has created a new registry titled \"COSE Header Parameters\". The registry has been created to use the \"Expert Review Required\" registration procedure [RFC8126]. Guidelines for the experts are provided in Section 16.11. It should be noted that, in addition to the expert review, some portions of the registry require a specification, potentially a Standards Track RFC, be supplied as well.\n\nThe columns of the registry are:\n\n- Name: The name is present to make it easier to refer to and discuss the registration entry. The value is not used in the protocol. Names are to be unique in the table.\n\n- Label: This is the value used for the label. The label can be either an integer or a string. Registration in the table is based on the value of the label requested. Integer values between 1 and 255 and strings of length 1 are designated as \"Standards Action\". Integer values from 256 to 65535 and strings of length 2 are designated as \"Specification Required\". Integer values of greater than 65535 and strings of length greater than 2 are designated as \"Expert Review\". Integer values in the range -1 to -65536 are \"delegated to the COSE Header Algorithm Parameters registry\". Integer values less than -65536 are marked as private use.\n\n- Value Type: This contains the CBOR type for the value portion of the label.\n\n- Value Registry: This contains a pointer to the registry used to contain values where the set is limited.\n\n- Description: This contains a brief description of the header field.\nReference: This contains a pointer to the specification defining the header field (where public).\n\nThe initial contents of the registry can be found in Tables 2 and 27. All of the entries in the \"References\" column of this registry point to this document.\n\nAdditionally, the label of 0 is to be marked as ‘Reserved’.\n\n16.3. COSE Header Algorithm Parameters Registry\n\nIANA has created a new registry titled \"COSE Header Algorithm Parameters\". The registry uses the \"Expert Review Required\" registration procedure. Expert review guidelines are provided in Section 16.11.\n\nThe columns of the registry are:\n\nName: The name is present to make it easier to refer to and discuss the registration entry. The value is not used in the protocol.\n\nAlgorithm: The algorithm(s) that this registry entry is used for. This value is taken from the \"COSE Algorithms\" registry. Multiple algorithms can be specified in this entry. For the table, the algorithm/label pair MUST be unique.\n\nLabel: This is the value used for the label. The label is an integer in the range of -1 to -65536.\n\nType: This contains the CBOR type for the value portion of the label.\n\nDescription: This contains a brief description of the header field.\n\nReference: This contains a pointer to the specification defining the header field (where public).\n\nThe initial contents of the registry can be found in Tables 13, 14, and 19. All of the entries in the \"References\" column of this registry point to this document.\n\n16.4. COSE Algorithms Registry\n\nIANA has created a new registry titled \"COSE Algorithms\". The registry has been created to use the \"Expert Review Required\" registration procedure. Guidelines for the experts are provided in\nSection 16.11. It should be noted that, in addition to the expert review, some portions of the registry require a specification, potentially a Standards Track RFC, be supplied as well.\n\nThe columns of the registry are:\n\nName: A value that can be used to identify an algorithm in documents for easier comprehension. The name SHOULD be unique. However, the ‘Value’ field is what is used to identify the algorithm, not the ‘name’ field.\n\nValue: The value to be used to identify this algorithm. Algorithm values MUST be unique. The value can be a positive integer, a negative integer, or a string. Integer values between -256 and 255 and strings of length 1 are designated as \"Standards Action\". Integer values from -65536 to 65535 and strings of length 2 are designated as \"Specification Required\". Integer values greater than 65535 and strings of length greater than 2 are designated as \"Expert Review\". Integer values less than -65536 are marked as private use.\n\nDescription: A short description of the algorithm.\n\nReference: A document where the algorithm is defined (if publicly available).\n\nRecommended: Does the IETF have a consensus recommendation to use the algorithm? The legal values are ‘Yes’, ‘No’, and ‘Deprecated’.\n\nThe initial contents of the registry can be found in Tables 5, 6, 7, 8, 9, 10, 11, 15, 16, 17, 18, and 20. All of the entries in the \"References\" column of this registry point to this document. All of the entries in the \"Recommended\" column are set to \"Yes\".\n\nAdditionally, the label of 0 is to be marked as ‘Reserved’.\n\nNOTE: The assignment of algorithm identifiers in this document was done so that positive numbers were used for the first layer objects (COSE_Sign, COSE_Sign1, COSE_Encrypt, COSE_Encrypt0, COSE_Mac, and COSE_Mac0). Negative numbers were used for second layer objects (COSE_Signature and COSE_recipient). Expert reviewers should consider this practice, but are not expected to be restricted by this precedent.\nIANA has created a new registry titled \"COSE Key Common Parameters\". The registry has been created to use the \"Expert Review Required\" registration procedure. Guidelines for the experts are provided in Section 16.11. It should be noted that, in addition to the expert review, some portions of the registry require a specification, potentially a Standards Track RFC, be supplied as well.\n\nThe columns of the registry are:\n\n**Name**: This is a descriptive name that enables easier reference to the item. It is not used in the encoding.\n\n**Label**: The value to be used to identify this algorithm. Key map labels MUST be unique. The label can be a positive integer, a negative integer, or a string. Integer values between 0 and 255 and strings of length 1 are designated as \"Standards Action\". Integer values from 256 to 65535 and strings of length 2 are designated as \"Specification Required\". Integer values of greater than 65535 and strings of length greater than 2 are designated as \"Expert Review\". Integer values in the range -65536 to -1 are \"used for key parameters specific to a single algorithm delegated to the COSE Key Type Parameters registry\". Integer values less than -65536 are marked as private use.\n\n**CBOR Type**: This field contains the CBOR type for the field.\n\n**Value Registry**: This field denotes the registry that values come from, if one exists.\n\n**Description**: This field contains a brief description for the field.\n\n**Reference**: This contains a pointer to the public specification for the field if one exists.\n\nThis registry has been initially populated by the values in Table 3. All of the entries in the \"References\" column of this registry point to this document.\n\n16.6. COSE Key Type Parameters Registry\n\nIANA has created a new registry titled \"COSE Key Type Parameters\". The registry has been created to use the \"Expert Review Required\" registration procedure. Expert review guidelines are provided in Section 16.11.\nThe columns of the table are:\n\n**Key Type:** This field contains a descriptive string of a key type. This should be a value that is in the \"COSE Key Common Parameters\" registry and is placed in the 'kty' field of a COSE Key structure.\n\n**Name:** This is a descriptive name that enables easier reference to the item. It is not used in the encoding.\n\n**Label:** The label is to be unique for every value of key type. The range of values is from -65536 to -1. Labels are expected to be reused for different keys.\n\n**CBOR Type:** This field contains the CBOR type for the field.\n\n**Description:** This field contains a brief description for the field.\n\n**Reference:** This contains a pointer to the public specification for the field if one exists.\n\nThis registry has been initially populated by the values in Tables 23, 24, and 25. All of the entries in the \"References\" column of this registry point to this document.\n\n### 16.7. COSE Key Types Registry\n\nIANA has created a new registry titled \"COSE Key Types\". The registry has been created to use the \"Expert Review Required\" registration procedure. Expert review guidelines are provided in Section 16.11.\n\nThe columns of this table are:\n\n**Name:** This is a descriptive name that enables easier reference to the item. The name MUST be unique. It is not used in the encoding.\n\n**Value:** This is the value used to identify the curve. These values MUST be unique. The value can be a positive integer, a negative integer, or a string.\n\n**Description:** This field contains a brief description of the curve.\n\n**References:** This contains a pointer to the public specification for the curve if one exists.\nThis registry has been initially populated by the values in Table 21. The specification column for all of these entries will be this document.\n\n16.8. COSE Elliptic Curves Registry\n\nIANA has created a new registry titled \"COSE Elliptic Curves\". The registry has been created to use the \"Expert Review Required\" registration procedure. Guidelines for the experts are provided in Section 16.11. It should be noted that, in addition to the expert review, some portions of the registry require a specification, potentially a Standards Track RFC, be supplied as well.\n\nThe columns of the table are:\n\nName: This is a descriptive name that enables easier reference to the item. It is not used in the encoding.\n\nValue: This is the value used to identify the curve. These values MUST be unique. The integer values from -256 to 255 are designated as \"Standards Action\". The integer values from 256 to 65535 and -65536 to -257 are designated as \"Specification Required\". Integer values over 65535 are designated as \"Expert Review\". Integer values less than -65536 are marked as private use.\n\nKey Type: This designates the key type(s) that can be used with this curve.\n\nDescription: This field contains a brief description of the curve.\n\nReference: This contains a pointer to the public specification for the curve if one exists.\n\nRecommended: Does the IETF have a consensus recommendation to use the algorithm? The legal values are 'Yes', 'No', and 'Deprecated'.\n\nThis registry has been initially populated by the values in Table 22. All of the entries in the \"References\" column of this registry point to this document. All of the entries in the \"Recommended\" column are set to \"Yes\".\n16.9. Media Type Registrations\n\n16.9.1. COSE Security Message\n\nThis section registers the 'application/cose' media type in the \"Media Types\" registry. These media types are used to indicate that the content is a COSE message.\n\nType name: application\n\nSubtype name: cose\n\nRequired parameters: N/A\n\nOptional parameters: cose-type\n\nEncoding considerations: binary\n\nSecurity considerations: See the Security Considerations section of RFC 8152.\n\nInteroperability considerations: N/A\n\nPublished specification: RFC 8152\n\nApplications that use this media type: IoT applications sending security content over HTTP(S) transports.\n\nFragment identifier considerations: N/A\n\nAdditional information:\n\n* Deprecated alias names for this type: N/A\n* Magic number(s): N/A\n* File extension(s): cbor\n* Macintosh file type code(s): N/A\n\nPerson & email address to contact for further information: iesg@ietf.org\n\nIntended usage: COMMON\n\nRestrictions on usage: N/A\n\nAuthor: Jim Schaad, ietf@augustcellars.com\nThis section registers the ‘application/cose-key’ and ‘application/cose-key-set’ media types in the \"Media Types\" registry. These media types are used to indicate, respectively, that content is a COSE_Key or COSE_KeySet object.\n\nThe template for registering ‘application/cose-key’ is:\n\nType name: application\nSubtype name: cose-key\nRequired parameters: N/A\nOptional parameters: N/A\nEncoding considerations: binary\nSecurity considerations: See the Security Considerations section of RFC 8152.\nInteroperability considerations: N/A\nPublished specification: RFC 8152\nApplications that use this media type: Distribution of COSE based keys for IoT applications.\nFragment identifier considerations: N/A\nAdditional information:\n* Deprecated alias names for this type: N/A\n* Magic number(s): N/A\n* File extension(s): cbor\n* Macintosh file type code(s): N/A\n\nPerson & email address to contact for further information: iesg@ietf.org\nIntended usage: COMMON\nRestrictions on usage: N/A\nAuthor: Jim Schaad, ietf@augustcellars.com\nChange Controller: IESG\nProvisional registration? No\n\nThe template for registering 'application/cose-key-set' is:\n\nType name: application\nSubtype name: cose-key-set\nRequired parameters: N/A\nOptional parameters: N/A\nEncoding considerations: binary\n\nSecurity considerations: See the Security Considerations section of RFC 8152.\n\nInteroperability considerations: N/A\n\nPublished specification: RFC 8152\n\nApplications that use this media type: Distribution of COSE based keys for IoT applications.\n\nFragment identifier considerations: N/A\n\nAdditional information:\n* Deprecated alias names for this type: N/A\n* Magic number(s): N/A\n* File extension(s): cbor\n* Macintosh file type code(s): N/A\n\nPerson & email address to contact for further information: iesg@ietf.org\n\nIntended usage: COMMON\nIANA has added the following entries to the \"CoAP Content-Formats\" registry.\n\n<table>\n<thead>\n<tr>\n<th>Media Type</th>\n<th>Encoding</th>\n<th>ID</th>\n<th>Reference</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>application/cose; cose-type="cose-sign"</td>\n<td></td>\n<td>98</td>\n<td>[RFC8152]</td>\n</tr>\n<tr>\n<td>application/cose; cose-type="cose-sign1"</td>\n<td></td>\n<td>18</td>\n<td>[RFC8152]</td>\n</tr>\n<tr>\n<td>application/cose; cose-type="cose-encrypt"</td>\n<td></td>\n<td>96</td>\n<td>[RFC8152]</td>\n</tr>\n<tr>\n<td>application/cose; cose-type="cose-encrypt0"</td>\n<td></td>\n<td>16</td>\n<td>[RFC8152]</td>\n</tr>\n<tr>\n<td>application/cose; cose-type="cose-mac"</td>\n<td></td>\n<td>97</td>\n<td>[RFC8152]</td>\n</tr>\n<tr>\n<td>application/cose; cose-type="cose-mac0"</td>\n<td></td>\n<td>17</td>\n<td>[RFC8152]</td>\n</tr>\n<tr>\n<td>application/cose-key</td>\n<td></td>\n<td>101</td>\n<td>[RFC8152]</td>\n</tr>\n<tr>\n<td>application/cose-key-set</td>\n<td></td>\n<td>102</td>\n<td>[RFC8152]</td>\n</tr>\n</tbody>\n</table>\n\nTable 26: CoAP Content-Formats for COSE\n\n16.11. Expert Review Instructions\n\nAll of the IANA registries established in this document are defined as expert review. This section gives some general guidelines for what the experts should be looking for, but they are being designated as experts for a reason, so they should be given substantial latitude.\n\nExpert reviewers should take into consideration the following points:\n\n- Point squatting should be discouraged. Reviewers are encouraged to get sufficient information for registration requests to ensure that the usage is not going to duplicate one that is already registered, and that the point is likely to be used in\ndeployments. The zones tagged as private use are intended for testing purposes and closed environments; code points in other ranges should not be assigned for testing.\n\n- Specifications are required for the standards track range of point assignment. Specifications should exist for specification required ranges, but early assignment before a specification is available is considered to be permissible. Specifications are needed for the first-come, first-serve range if they are expected to be used outside of closed environments in an interoperable way. When specifications are not provided, the description provided needs to have sufficient information to identify what the point is being used for.\n\n- Experts should take into account the expected usage of fields when approving point assignment. The fact that there is a range for standards track documents does not mean that a standards track document cannot have points assigned outside of that range. The length of the encoded value should be weighed against how many code points of that length are left, the size of device it will be used on, and the number of code points left that encode to that size.\n\n- When algorithms are registered, vanity registrations should be discouraged. One way to do this is to require registrations to provide additional documentation on security analysis of the algorithm. Another thing that should be considered is requesting an opinion on the algorithm from the Crypto Forum Research Group (CFRG). Algorithms that do not meet the security requirements of the community and the messages structures should not be registered.\n\n17. Security Considerations\n\nThere are a number of security considerations that need to be taken into account by implementers of this specification. The security considerations that are specific to an individual algorithm are placed next to the description of the algorithm. While some considerations have been highlighted here, additional considerations may be found in the documents listed in the references.\n\nImplementations need to protect the private key material for any individuals. There are some cases in this document that need to be highlighted on this issue.\n\n- Using the same key for two different algorithms can leak information about the key. It is therefore recommended that keys be restricted to a single algorithm.\nUse of ‘direct’ as a recipient algorithm combined with a second recipient algorithm exposes the direct key to the second recipient.\n\nSeveral of the algorithms in this document have limits on the number of times that a key can be used without leaking information about the key.\n\nThe use of ECDH and direct plus KDF (with no key wrap) will not directly lead to the private key being leaked; the one way function of the KDF will prevent that. There is, however, a different issue that needs to be addressed. Having two recipients requires that the CEK be shared between two recipients. The second recipient therefore has a CEK that was derived from material that can be used for the weak proof of origin. The second recipient could create a message using the same CEK and send it to the first recipient; the first recipient would, for either static-static ECDH or direct plus KDF, make an assumption that the CEK could be used for proof of origin even though it is from the wrong entity. If the key wrap step is added, then no proof of origin is implied and this is not an issue.\n\nAlthough it has been mentioned before, the use of a single key for multiple algorithms has been demonstrated in some cases to leak information about a key, provide the opportunity for attackers to forge integrity tags, or gain information about encrypted content. Binding a key to a single algorithm prevents these problems. Key creators and key consumers are strongly encouraged not only to create new keys for each different algorithm, but to include that selection of algorithm in any distribution of key material and strictly enforce the matching of algorithms in the key structure to algorithms in the message structure. In addition to checking that algorithms are correct, the key form needs to be checked as well. Do not use an ‘EC2’ key where an ‘OKP’ key is expected.\n\nBefore using a key for transmission, or before acting on information received, a trust decision on a key needs to be made. Is the data or action something that the entity associated with the key has a right to see or a right to request? A number of factors are associated with this trust decision. Some of the ones that are highlighted here are:\n\n- What are the permissions associated with the key owner?\n- Is the cryptographic algorithm acceptable in the current context?\n- Have the restrictions associated with the key, such as algorithm or freshness, been checked and are they correct?\nIs the request something that is reasonable, given the current state of the application?\n\nHave any security considerations that are part of the message been enforced (as specified by the application or ‘crit’ parameter)?\n\nThere are a large number of algorithms presented in this document that use nonce values. For all of the nonces defined in this document, there is some type of restriction on the nonce being a unique value either for a key or for some other conditions. In all of these cases, there is no known requirement on the nonce being both unique and unpredictable; under these circumstances, it’s reasonable to use a counter for creation of the nonce. In cases where one wants the pattern of the nonce to be unpredictable as well as unique, one can use a key created for that purpose and encrypt the counter to produce the nonce value.\n\nOne area that has been starting to get exposure is doing traffic analysis of encrypted messages based on the length of the message. This specification does not provide for a uniform method of providing padding as part of the message structure. An observer can distinguish between two different strings (for example, ‘YES’ and ‘NO’) based on the length for all of the content encryption algorithms that are defined in this document. This means that it is up to the applications to document how content padding is to be done in order to prevent or discourage such analysis. (For example, the strings could be defined as ‘YES’ and ‘NO’.)\n\n18. References\n\n18.1. Normative References\n\n\nNIST.FIPS.186-4.pdf>.\n\n\n18.2. Informative References\n\n\nSchaad Standards Track [Page 94]\n[W3C.WebCrypto]\nAppendix A. Guidelines for External Data Authentication of Algorithms\n\nA portion of the working group has expressed a strong desire to relax the rule that the algorithm identifier be required to appear in each level of a COSE object. There are two basic reasons that have been advanced to support this position. First, the resulting message will be smaller if the algorithm identifier is omitted from the most common messages in a CoAP environment. Second, there is a potential bug that will arise if full checking is not done correctly between the different places that an algorithm identifier could be placed (the message itself, an application statement, the key structure that the sender possesses, and the key structure the recipient possesses).\n\nThis appendix lays out how such a change can be made and the details that an application needs to specify in order to use this option. Two different sets of details are specified: those needed to omit an algorithm identifier and those needed to use a variant on the counter signature attribute that contains no attributes about itself.\n\nA.1. Algorithm Identification\n\nIn this section, three sets of recommendations are laid out. The first set of recommendations apply to having an implicit algorithm identified for a single layer of a COSE object. The second set of recommendations apply to having multiple implicit algorithms identified for multiple layers of a COSE object. The third set of recommendations apply to having implicit algorithms for multiple COSE object constructs.\n\nThe key words from RFC 2119 are deliberately not used here. This specification can provide recommendations, but it cannot enforce them.\n\nThis set of recommendations applies to the case where an application is distributing a fixed algorithm along with the key information for use in a single COSE object. This normally applies to the smallest of the COSE objects, specifically COSE_Sign1, COSE_Mac0, and COSE_Encrypt0, but could apply to the other structures as well.\n\nThe following items should be taken into account:\n\n- Applications need to list the set of COSE structures that implicit algorithms are to be used in. Applications need to require that the receipt of an explicit algorithm identifier in one of these structures will lead to the message being rejected. This requirement is stated so that there will never be a case where there is any ambiguity about the question of which algorithm should be used, the implicit or the explicit one. This applies\neven if the transported algorithm identifier is a protected attribute. This applies even if the transported algorithm is the same as the implicit algorithm.\n\n- Applications need to define the set of information that is to be considered to be part of a context when omitting algorithm identifiers. At a minimum, this would be the key identifier (if needed), the key, the algorithm, and the COSE structure it is used with. Applications should restrict the use of a single key to a single algorithm. As noted for some of the algorithms in this document, the use of the same key in different related algorithms can lead to leakage of information about the key, leakage about the data or the ability to perform forgeries.\n\n- In many cases, applications that make the algorithm identifier implicit will also want to make the context identifier implicit for the same reason. That is, omitting the context identifier will decrease the message size (potentially significantly depending on the length of the identifier). Applications that do this will need to describe the circumstances where the context identifier is to be omitted and how the context identifier is to be inferred in these cases. (An exhaustive search over all of the keys would normally not be considered to be acceptable.) An example of how this can be done is to tie the context to a transaction identifier. Both would be sent on the original message, but only the transaction identifier would need to be sent after that point as the context is tied into the transaction identifier. Another way would be to associate a context with a network address. All messages coming from a single network address can be assumed to be associated with a specific context. (In this case, the address would normally be distributed as part of the context.)\n\n- Applications cannot rely on key identifiers being unique unless they take significant efforts to ensure that they are computed in such a way as to create this guarantee. Even when an application does this, the uniqueness might be violated if the application is run in different contexts (i.e., with a different context provider) or if the system combines the security contexts from different applications together into a single store.\n\n- Applications should continue the practice of protecting the algorithm identifier. Since this is not done by placing it in the protected attributes field, applications should define an application-specific external data structure that includes this value. This external data field can be used as such for content encryption, MAC, and signature algorithms. It can be used in the SuppPrivInfo field for those algorithms that use a KDF to derive a\nkey value. Applications may also want to protect other information that is part of the context structure as well. It should be noted that those fields, such as the key or a Base IV, are protected by virtue of being used in the cryptographic computation and do not need to be included in the external data field.\n\nThe second case is having multiple implicit algorithm identifiers specified for a multiple layer COSE object. An example of how this would work is the encryption context that an application specifies, which contains a content encryption algorithm, a key wrap algorithm, a key identifier, and a shared secret. The sender omits sending the algorithm identifier for both the content layer and the recipient layer leaving only the key identifier. The receiver then uses the key identifier to get the implicit algorithm identifiers.\n\nThe following additional items need to be taken into consideration:\n\n- Applications that want to support this will need to define a structure that allows for, and clearly identifies, both the COSE structure to be used with a given key and the structure and algorithm to be used for the secondary layer. The key for the secondary layer is computed as normal from the recipient layer.\n\nThe third case is having multiple implicit algorithm identifiers, but targeted at potentially unrelated layers or different COSE objects. There are a number of different scenarios where this might be applicable. Some of these scenarios are:\n\n- Two contexts are distributed as a pair. Each of the contexts is for use with a COSE_Encrypt message. Each context will consist of distinct secret keys and IVs and potentially even different algorithms. One context is for sending messages from party A to party B, and the second context is for sending messages from party B to party A. This means that there is no chance for a reflection attack to occur as each party uses different secret keys to send its messages; a message that is reflected back to it would fail to decrypt.\n\n- Two contexts are distributed as a pair. The first context is used for encryption of the message, and the second context is used to place a counter signature on the message. The intention is that the second context can be distributed to other entities independently of the first context. This allows these entities to validate that the message came from an individual without being able to decrypt the message and see the content.\nTwo contexts are distributed as a pair. The first context contains a key for dealing with MACed messages, and the second context contains a key for dealing with encrypted messages. This allows for a unified distribution of keys to participants for different types of messages that have different keys, but where the keys may be used in a coordinated manner.\n\nFor these cases, the following additional items need to be considered:\n\n- Applications need to ensure that the multiple contexts stay associated. If one of the contexts is invalidated for any reason, all of the contexts associated with it should also be invalidated.\n\nA.2. Counter Signature without Headers\n\nThere is a group of people who want to have a counter signature parameter that is directly tied to the value being signed, and thus the authenticated and unauthenticated buckets can be removed from the message being sent. The focus on this is an even smaller size, as all of the information on the process of creating the counter signature is implicit rather than being explicitly carried in the message. This includes not only the algorithm identifier as presented above, but also items such as the key identification, which is always external to the signature structure. This means that the entities that are doing the validation of the counter signature are required to infer which key is to be used from context rather than being explicit. One way of doing this would be to presume that all data coming from a specific port (or to a specific URL) is to be validated by a specific key. (Note that this does not require that the key identifier be part of the value signed as it does not serve a cryptographic purpose. If the key validates the counter signature, then it should be presumed that the entity associated with that key produced the signature.)\n\nWhen computing the signature for the bare counter signature header, the same Sig_structure defined in Section 4.4 is used. The sign_protected field is omitted, as there is no protected header field in this counter signature header. The value of \"CounterSignature0\" is placed in the context field of the Sig_structure.\nAll of the currently defined recipient algorithm classes only use two layers of the COSE_Encrypt structure. The first layer is the message content, and the second layer is the content key encryption. However, if one uses a recipient algorithm such as the RSA Key Encapsulation Mechanism (RSA-KEM) (see Appendix A of RSA-KEM [RFC5990]), then it makes sense to have three layers of the COSE_Encrypt structure.\n\nThese layers would be:\n\n- Layer 0: The content encryption layer. This layer contains the payload of the message.\n- Layer 1: The encryption of the CEK by a KEK.\n- Layer 2: The encryption of a long random secret using an RSA key and a key derivation function to convert that secret into the KEK.\n\nThis is an example of what a triple layer message would look like. The message has the following layers:\n\n- Layer 0: Has a content encrypted with AES-GCM using a 128-bit key.\n- Layer 1: Uses the AES Key Wrap algorithm with a 128-bit key.\n- Layer 2: Uses ECDH Ephemeral-Static direct to generate the layer 1 key.\nIn effect, this example is a decomposed version of using the ECDH-ES+A128KW algorithm.\n\nSize of binary file is 183 bytes\n\n```\n96{\n [ \n / protected / h’a10101’ / {\n \\ alg \\ 1:1 \\ AES-GCM 128 \\ \n } / ,\n / unprotected / {\n / iv / 5:h’02d1f7e6f26c43d4868d87ce’ ,\n / ciphertext / h’64f84d913ba60a76070a9a48f26e97e863e2852948658f0811139868826e89218a75715b’ ,\n / recipients / [ \n [ / protected / h’’ ,\n / unprotected / {\n / alg / 1:-3 / A128KW / \n },\n / ciphertext / h’dbd43c4e9d719c27c6275c67d628d493f090593db8218f11’ ,\n / recipients / [ \n [ / protected / h’a1013818’ / {\n \\ alg \\ 1:25 \\ ECDH-ES + HKDF-256 \\ \n } / ,\n / unprotected / {\n / ephemeral / -1:{\n / kty / 1:2,\n / crv / -1:1,\n / x / -2:h’b2add44368ea6d641f9ca9af308b4079aeb519f11e9b8a55a600b21233e86e68’ ,\n / y / -3:0\n },\n / kid / 4:’meriadoc.brandybuck@buckland.example’\n },\n / ciphertext / h’’\n ]\n ]\n]\n```\nAppendix C. Examples\n\nThis appendix includes a set of examples that show the different features and message types that have been defined in this document. To make the examples easier to read, they are presented using the extended CBOR diagnostic notation (defined in [CDDL]) rather than as a binary dump.\n\nA GitHub project has been created at <https://github.com/cose-wg/Examples> that contains not only the examples presented in this document, but a more complete set of testing examples as well. Each example is found in a JSON file that contains the inputs used to create the example, some of the intermediate values that can be used in debugging the example and the output of the example presented in both a hex and a CBOR diagnostic notation format. Some of the examples at the site are designed failure testing cases; these are clearly marked as such in the JSON file. If errors in the examples in this document are found, the examples on GitHub will be updated, and a note to that effect will be placed in the JSON file.\n\nAs noted, the examples are presented using the CBOR’s diagnostic notation. A Ruby-based tool exists that can convert between the diagnostic notation and binary. This tool can be installed with the command line:\n\n```bash\ngem install cbor-diag\n```\n\nThe diagnostic notation can be converted into binary files using the following command line:\n\n```bash\ndiag2cbor.rb < inputfile > outputfile\n```\n\nThe examples can be extracted from the XML version of this document via an XPath expression as all of the artwork is tagged with the attribute type=’CBORdiag’. (Depending on the XPath evaluator one is using, it may be necessary to deal with > as an entity.)\n\n```xml\n//artwork[@type='CDDL']/text()\n```\nC.1. Examples of Signed Messages\n\nC.1.1. Single Signature\n\nThis example uses the following:\n\n- Signature Algorithm: ECDSA w/ SHA-256, Curve P-256\n\nSize of binary file is 103 bytes\n\n```\n98{\n / protected / h’’,\n / unprotected / {},\n / payload / ‘This is the content.’,\n / signatures / [\n / protected / h’a10126’ / {\n \\ alg \\ 1:-7 \\ ECDSA 256 \\\\n } / ,\n / unprotected / {\n / kid / 4:’11’\n },\n / signature / h’e2aeaf40d69d19dfe6e52077c5d7ff4e408282cbebf5d06cbf414af2e19d98ac45ac98b8544c908b4507de8e0b717c3d34816fe926a2b98f53af2fa0f30a’\n ]\n}\n```\n\nC.1.2. Multiple Signers\n\nThis example uses the following:\n\n- Signature Algorithm: ECDSA w/ SHA-256, Curve P-256\n- Signature Algorithm: ECDSA w/ SHA-512, Curve P-521\nC.1.3. Counter Signature\n\nThis example uses the following:\n\n- Signature Algorithm: ECDSA w/ SHA-256, Curve P-256\n- The same parameters are used for both the signature and the counter signature.\nSize of binary file is 180 bytes\n\n98{\n / protected / h’’,\n / unprotected / {\n / countersign / 7:[\n / protected / h’a10126' / {\n \\ alg \\ 1:-7 \\ ECDSA 256 \\\\n } / ,\n / unprotected / {\n / kid / 4:'11'\n },\n / signature / h’5ac05e289d5d0e1b0a7f048a5d2b643813ded50bc9e49220f4f7278f85f19d4a77d655c9d3b51e805a74b099e1e085aacd97fc29d72f887e8802bb6650ccceb2c’\n },\n / payload / 'This is the content.',\n / signatures / [\n / protected / h’a10126' / {\n \\ alg \\ 1:-7 \\ ECDSA 256 \\\\\n } / ,\n / unprotected / {\n / kid / 4:'11'\n },\n / signature / h’e2aeafa4d40d69d19dfe6e52077c5d7ff4e408282cbefb5d06c0f4f414af2e19d98245ac98b8544c908b4557defe190b717c3d34816fe926a2b98f53af2fa0f30a’\n ]\n ]\n }\n}\n\nC.1.4. Signature with Criticality\n\nThis example uses the following:\n\n- Signature Algorithm: ECDSA w/ SHA-256, Curve P-256\n\n- There is a criticality marker on the \"reserved\" header parameter\nSize of binary file is 125 bytes\n\n98(\n [\n / protected / h'a2687265736572766564f40281687265736572766564' /\n {\n \"reserved\":false,\n \\ crit \\ 2:[\n \"reserved\"\n ]\n } / ,\n / unprotected / {},\n / payload / 'This is the content.',\n / signatures / [\n [\n / protected / h'a10126' / {\n \\ alg \\ 1:-7 \\ ECDSA 256 \\\n } / ,\n / unprotected / {\n / kid / 4:'11'\n },\n / signature / h'3fc54702aa56e1b2cb20284294c9106a63f91bac658d69351210a031d8fc7c5ff3e4be39445b1a3e83e1510d1aca2f2e8a7c081c7645042bl8aba9d1fad1bd9c'\n ]\n ]\n ]\n)\n\nC.2. Single Signer Examples\n\nC.2.1. Single ECDSA Signature\n\nThis example uses the following:\n\n- Signature Algorithm: ECDSA w/ SHA-256, Curve P-256\nC.3. Examples of Enveloped Messages\n\nC.3.1. Direct ECDH\n\nThis example uses the following:\n\n- CEK: AES-GCM w/ 128-bit key\n- Recipient class: ECDH Ephemeral-Static, Curve P-256\nC.3.2. Direct Plus Key Derivation\n\nThis example uses the following:\n\n- CEK: AES-CCM w/ 128-bit key, truncate the tag to 64 bits\n- Recipient class: Use HKDF on a shared secret with the following implicit fields as part of the context.\n * salt: \"aabbcddedefgghh\"\n * PartyU identity: \"lighting-client\"\n * PartyV identity: \"lighting-server\"\n* Supplementary Public Other: \"Encryption Example 02\"\n\nSize of binary file is 91 bytes\n\n96{\n [ \n / protected / h'a1010a' / { \n \\ alg \\ 1:10 \\ AES-CCM-16-64-128 \\ \n } / , \n / unprotected / { \n / iv / 5:h'89f52f65a1c580933b5261a76c' \n }, \n / ciphertext / h'753548a19b1307084ca7b2056924ed95f2e3b17006dfe931b687b847', \n / recipients / [ \n [ \n / protected / h'a10129' / { \n \\ alg \\ 1:-10 \n } / , \n / unprotected / { \n / salt / -20:'aabccddeeffghh', \n / kid / 4:'our-secret' \n }, \n / ciphertext / h'' \n ] \n ] \n ]\n}\n\nC.3.3. Counter Signature on Encrypted Content\n\nThis example uses the following:\n\n- CEK: AES-GCM w/ 128-bit key\n- Recipient class: ECDH Ephemeral-Static, Curve P-256\nSize of binary file is 326 bytes\n\n96{\n [ \n / protected / h’a10101’ / {\n \\ alg \\ 1:1 \\ AES-GCM 128 \\ }\n },\n / unprotected / {\n / iv / 5:h’c9cf4df2fe6c632bf7886413’,\n / countersign / 7:[\n / protected / h’a1013823’ / {\n \\ alg \\ 1:-36\n }\n },\n / unprotected / {\n / kid / 4:‘bilbo.baggins@hobbiton.example’\n },\n / signature / h’00929663c8789bb28177ae28467e66377da12302d7f9594d2999a5fda531294f8896f2b6cdff71740014f4c7f1a358e3a6cf57f4ed6fb02fcf87aa989f5fdd07f0700a3a7d8f3c604ba70fa9411bd10c2591b483e1d2c31de003183e434d8fba18f17a4c7e3dfa003ac1cf3d30d44d2533c4989d3ac38c38b71481cc3430c9d65e7ddff’\n },\n / ciphertext / h’7adbe2709ca818fb415f1e5df66f4e1a51053ba6d65a10c52a357da7a644b8070a151b0’,\n / recipients / [\n [ \n / protected / h’a1013818’ / {\n \\ alg \\ 1:-25 \\ ECDH-ES + HKDF-256 \n }\n },\n / unprotected / {\n / ephemeral / -1:{\n / kty / 1:2,\n / crv / -1:1,\n / x / -2:h’98f50a4ff6c05861c8860d13a638ea56c3f5ad7590bbf054e1c7b4d91d6280’,\n / y / -3:true\n },\n / kid / 4:‘meriadoc.brandybuck@buckland.example’\n },\n / ciphertext / h’\n ]\n] }\nC.3.4. Encrypted Content with External Data\n\nThis example uses the following:\n\n- **CEK**: AES-GCM w/ 128-bit key\n- **Recipient class**: ECDH static-Static, Curve P-256 with AES Key Wrap\n- **Externally Supplied AAD**: h‘0011bbcc22dd44ee55ff660077’\n\nSize of binary file is 173 bytes\n\n```cose\n96( [\n / protected / h’a10101’ / {\n \\ alg \\ 1:1 \\ AES-GCM 128 \\\n } ,\n / unprotected / {\n / iv / 5:h’02d1f7e6f26c43d4868d87ce’\n },\n / ciphertext / h’64f84d913ba60a76070a9a48f26e97e863e28529d8f535\n e5f0165ee976b4a5f6c6f09d’,\n / recipients / [ { [ / protected / h’a101381f’ / { \n \\ alg \\ 1:-32 \\ ECHD-SS+A128KW \\\n } ,\n / unprotected / { / static kid / -3:’peregrin.took@tuckborough.example’,\n / kid / 4:’meriadoc.brandybuck@buckland.example’,\n / U nonce / -22:h’0101’\n }],\n / ciphertext / h’41e0d76f579dbd0d936a662d54d8582037de2e366fd\n e1c62’\n ]\n ]\n] )\n```\n\nC.4. Examples of Encrypted Messages\n\nC.4.1. Simple Encrypted Message\n\nThis example uses the following:\n\n- **CEK**: AES-CCM w/ 128-bit key and a 64-bit tag\nSize of binary file is 52 bytes\n\n16(\n [ / protected / h'a1010a' / {\n \\ alg \\ 1:10 \\ AES-CCM-16-64-128 \\ \n } / ,\n / unprotected / {\n / iv / 5:h'89f52f65a1c580933b5261a78c'\n },\n / ciphertext / h'5974e1b99a3a4cc09a659aa2e9e7fff161d38ce71cb45ce460ffb569'\n ]\n)\n\nC.4.2. Encrypted Message with a Partial IV\n\nThis example uses the following:\n\no CEK: AES-CCM w/ 128-bit key and a 64-bit tag\n\no Prefix for IV is 89F52F65A1C580933B52\n\nSize of binary file is 41 bytes\n\n16(\n [ / protected / h'a1010a' / {\n \\ alg \\ 1:10 \\ AES-CCM-16-64-128 \\ \n } / ,\n / unprotected / {\n / partial iv / 6:h'61a7'\n },\n / ciphertext / h'252a8911d465c125b6764739700f0141ed09192de139e053bd09abca'\n ]\n)\n\nC.5. Examples of MACed Messages\n\nC.5.1. Shared Secret Direct MAC\n\nThis example uses the following:\n\no MAC: AES-CMAC, 256-bit key, truncated to 64 bits\n\no Recipient class: direct shared secret\nSize of binary file is 57 bytes\n\n97{\n / protected / h'a1010f' / {\n \\ alg \\ 1:15 \\ AES-CBC-MAC-256//64 \\ \n } / ,\n / unprotected / {},\n / payload / 'This is the content.',\n / tag / h'9e1226ba1f81b848',\n / recipients / [\n / protected / h'\",\n / unprotected / {\n / alg / 1:-6 / direct /,\n / kid / 4:'our-secret'\n },\n / ciphertext / h''\n ]\n}\n\nC.5.2. ECDH Direct MAC\n\nThis example uses the following:\n\n o MAC: HMAC w/SHA-256, 256-bit key\n\n o Recipient class: ECDH key agreement, two static keys, HKDF w/ context structure\nC.5.3. Wrapped MAC\n\nThis example uses the following:\n\n- MAC: AES-MAC, 128-bit key, truncated to 64 bits\n- Recipient class: AES Key Wrap w/ a pre-shared 256-bit key\nC.5.4. Multi-Recipient MACed Message\n\nThis example uses the following:\n\n- MAC: HMAC w/ SHA-256, 128-bit key\n- Recipient class: Uses three different methods\n 1. ECDH Ephemeral-Static, Curve P-521, AES Key Wrap w/ 128-bit key\n 2. AES Key Wrap w/ 256-bit key\nSize of binary file is 309 bytes\n\n97{\n [ \n / protected / h’a10105’ / { \n \\ alg \\ 1:5 \\ HMAC 256//256 \n } / , \n / unprotected / {}, \n / payload / ’This is the content.’, \n / tag / h’bf48235e809b5c42e995f2b7d5fa13620e7ed834e337f6aa43df161e49e9323e’, \n / recipients / [ \n [ \n / protected / h’a101381c’ / { \n \\ alg \\ 1:-29 \\ ECHD-ES+A128KW \n } / , \n / ephemeral / -1:{ \n / kty / 1:2, \n / crv / -1:3, \n / x / -2:h’0043b12669acac3fd27898ffba0bcd2e6c366d53bc4db71f909a759304acfb5e18c7ba0b13ff8c7636271a6924b1ac63c02688075b55ef2d613574e7dc242f79c3’, \n / y / -3:true \n }, \n / kid / 4:’bilbo.baggins@hobbiton.example’ \n ], \n / ciphertext / h’339bc4f79984cdec63e6ce5f315a4c7d2b0ac466fca69e8c07d6bca5bb1f661bc5f8e0df9e3eff5’ \n ], \n [ \n / protected / h’’, \n / unprotected / { \n / alg / 1:-5 / A256KW / , \n / kid / 4:’018c0ae5-4d9b-471b-bfd6-eef314bc7037’ \n }, \n / ciphertext / h’0b2c7cfce04e98276342d6476a7723c090dfdd15f9a518e7736549e998370695e6d6a83b4ae507bb’ \n ] \n ] \n}\nC.6. Examples of MAC0 Messages\n\nC.6.1. Shared Secret Direct MAC\n\nThis example uses the following:\n\n- MAC: AES-CMAC, 256-bit key, truncated to 64 bits\n- Recipient class: direct shared secret\n\nSize of binary file is 37 bytes\n\n17{\n / protected / h’a1010f’ / {\n \\ alg \\ 1:15 \\ AES-CBC-MAC-256//64 \\ \n },\n / unprotected / {},\n / payload / ‘This is the content.’,\n / tag / h’726043745027214f’\n}\n\nNote that this example uses the same inputs as Appendix C.5.1.\n\nC.7. COSE Keys\n\nC.7.1. Public Keys\n\nThis is an example of a COSE Key Set. This example includes the public keys for all of the previous examples.\n\nIn order the keys are:\n\n- An EC key with a kid of \"meriadoc.brandybuck@buckland.example\"\n- An EC key with a kid of \"peregrin.took@tuckborough.example\"\n- An EC key with a kid of \"bilbo.baggins@hobbiton.example\"\n- An EC key with a kid of \"11\"\nSize of binary file is 481 bytes\n\n[\n {\n -1:1,\n -2:'h'65eda5a12577c2bae829437fe338701a10aaa375e1bb5b5de108de439c08551d',\n -3:'h'1e52ed75701163f7f9e40ddf9f341b3dc9ba860af7e0ca7ca7e9eecd0084d19c',\n 1:2,\n 2:'meriadoc.brandybuck@buckland.example'\n },\n {\n -1:1,\n -2:'h'bac5b11cad8f99f9c72b05cf4b9e26d244dc189f745228255a219a86d6a09eff',\n -3:'h'20138bf82dc1b6d562be0fa54ab7804a3a64b6d72ccfed6b6fb6ed28bbfc117e',\n 1:2,\n 2:'11'\n },\n {\n -1:3,\n -2:'h'0072992cb3ac08ecf3e5c63dedec0d51a8c1f79ef2f02f94f3c737bf5de7986671eac625fe8257bbd0394644caaa3aaf8f27a4585fbbcad0f2457620085e5c8f42ad',\n -3:'h'01dca6947bce88bc5790485ac97427342bc35f887d86d65a089377e247e60baa55e4e8501e2ada5724ac51d6909008033ebc10ac999b9d7f5cc2519f3fe1ea1d9475',\n 1:2,\n 2:'bilbo.baggins@hobbiton.example'\n },\n {\n -1:1,\n -2:'h'98f50a4ff6c05861c8860d13a638ea56c3f5ad7590bbbf054e1c7b4d91d6280',\n -3:'h'f01400b089867804b8e9fc96c3932161f1934f4223069170d924b7e03bf822bb',\n 1:2,\n 2:'peregrin.took@tuckborough.example'\n }\n]\nC.7.2. Private Keys\n\nThis is an example of a COSE Key Set. This example includes the private keys for all of the previous examples.\n\nIn order the keys are:\n\n- An EC key with a kid of \"meriadoc.brandybuck@buckland.example\"\n- A shared-secret key with a kid of \"our-secret\"\n- An EC key with a kid of \"peregrin.took@tuckborough.example\"\n- A shared-secret key with a kid of \"018c0ae5-4d9b-471b-bfd6-eef314bc7037\"\n- An EC key with a kid of \"bilbo.baggins@hobbiton.example\"\n- An EC key with a kid of \"11\"\n\nSize of binary file is 816 bytes\n\n```json\n[\n {\n 1:2,\n 2:'meriadoc.brandybuck@buckland.example',\n -1:1,\n -2:h'65eda5a12577c2bae829437fe338701a10aaa375e1bb5b5de108de439c08551d',\n -3:h'1e52ed75701163f7f9e40ddf9f341b3dc9ba860af7e0ca7ca7e9eed0084d19c',\n -4:h'af907c99f9ad3aae6c4cdef21122bce2bd68b5283e6907154ad911840fa208cf'\n },\n {\n 1:2,\n 2:'11',\n -1:1,\n -2:h'bac5b11cad8f99f9c72b05cf4b9e26d244dc189f745228255a219a86d6a09eff',\n -3:h'20138f82d1b6d562be0fa54ab7804a3a64b6d72ccfed6b6f6ed28bbf\nc117e',\n -4:h'57c92077664146e876760c9520d054aa93c3afb04e306705db6090308507b4d3'\n },\n {\n 1:2,\n 2:'bilbo.baggins@hobbiton.example',\n```\n-1:3,\n -2: h'0072992cb3ac08ecf3e5c63dedec0d51a8c1f79ef2f82f94f3c737bf5de7986671eac625fe8257bbd0394644caaa3aaf8f27a4585fbbcad0f2457620085e5c8f42ad',\n -3: h'01dca6947bce88bc5790485ac97427342bc35f887d86d65a089377e247e60baa55e4e8501e2ada5724ac51d6909008033ebc10ac999b9d7f5cc2519f3felea1d9475',\n -4: h'00085138ddabf5ca975f5860f91a08e91d65f9a76ad4018766a476680b55cd339e8ab6c72b5facdb2a2a50ac25bd086647dd3e2e6e99e84ca2c3609fdf177febeb6d'\n},\n \n 1:4,\n 2: 'our-secret',\n -1: h'849b57219dae48de646d07dbb533566e976686457c1491be3a76dce6a447188'\n},\n \n 1:2,\n 1:1,\n 2: 'peregrin.took@tuckborough.example',\n -2: h'98f50a4ff6c05861c8860d13a638ea56c3f5ad7590bbbf0541c7b4d91d6280',\n -3: h'f01400b089867804b8e9fc96c3932161f1934f4223069170d924b7e03bf822bb',\n -4: h'02d1f7e6f26c43d4868d87ceb2353161740aacf1f7163647984b522a848df1c3'\n},\n \n 1:4,\n 2: 'our-secret2',\n -1: h'849b5786457c1491be3a76dce6a4271',\n \n 1:4,\n 2: '018c0ae5-4d9b-471b-bfd6-eef314bc7037',\n -1: h'849b57219dae48de646d07dbb533566e976686457c1491be3a76dce6a447188'\nAcknowledgments\n\nThis document is a product of the COSE working group of the IETF.\n\nThe following individuals are to blame for getting me started on this project in the first place: Richard Barnes, Matt Miller, and Martin Thomson.\n\nThe initial version of the specification was based to some degree on the outputs of the JOSE and S/MIME working groups.\n\nThe following individuals provided input into the final form of the document: Carsten Bormann, John Bradley, Brain Campbell, Michael B. Jones, Ilari Liusvaara, Francesca Palombini, Ludwig Seitz, and Goran Selander.\n\nAuthor’s Address\n\nJim Schaad\nAugust Cellars\n\nEmail: ietf@augustcellars.com"}}},{"rowIdx":60,"cells":{"id":{"kind":"string","value":"01857f1da7f2c217194761abbef87248cacd2690"},"text":{"kind":"string","value":"Hybrid Multiparty Session Types - Full Version\nCompositionality for Protocol Specification through Endpoint Projection\n\nLORENZO GHERI, University of Oxford, United Kingdom\nNOBUKO YOSHIDA, University of Oxford, United Kingdom\n\nMultiparty session types (MPST) are a specification and verification framework for distributed message-passing systems. The communication protocol of the system is specified as a global type, from which a collection of local types (local process implementations) is obtained by endpoint projection. A global type is a single disciplining entity for the whole system, specified by one designer that has full knowledge of the communication protocol. On the other hand, distributed systems are often described in terms of their components: a different designer is in charge of providing a subprotocol for each component. The problem of modular specification of global protocols has been addressed in the literature, but the state of the art focuses only on dual input/output compatibility. Our work overcomes this limitation. We propose the first MPST theory of multiparty compositionality for distributed protocol specification that is semantics-preserving, allows the composition of two or more components, and retains full MPST expressiveness. We introduce hybrid types for describing subprotocols interacting with each other, define a novel compatibility relation, explicitly describe an algorithm for composing multiple subprotocols into a well-formed global type, and prove that compositionality preserves projection, thus retaining semantic guarantees, such as liveness and deadlock freedom. Finally, we test our work against real-world case studies and we smoothly extend our novel compatibility to MPST with delegation and explicit connections.\n\nCCS Concepts: • Theory of computation → Distributed computing models; Type theory.\n\nAdditional Key Words and Phrases: multiparty session types, compositionality, protocol design, concurrency\n\nACM Reference Format:\n\n1 INTRODUCTION\n\nWith the current growth in scale and complexity of systems, their design has become of central importance for industry and society in general. Choreographies for interactions among multiple participants, or (communication) protocols, arise naturally in numerous fields: authorisation standards [Hardt 2012; MIT 2022], the BPMN graphical specification for business processes [OMG 2022], or smart contracts for financial transactions [Ethereum 2022].\n\nThe literature on programming languages offers a variety of formal frameworks for protocol description [Barbanera et al. 2020a; Honda et al. 2016; Montesi 2013], aimed at the verification of behavioural properties of distributed implementations that comply with the communication discipline prescribed by the protocol. Such theories focus on distributed implementations of participants, but rarely feature modularity in the design of protocols, which are instead seen as standalone, monolithic entities. Mostly, when modularity is considered, it is either conceived in terms of nesting [Demangeon and Honda 2012; Tabareau et al. 2014] or it substantially modifies protocol description, by adding additional structure [Carbone et al. 2018; Montesi and Yoshida 2013; Savanovic et al. 2020]. To the best of our knowledge, only in [Barbanera et al. 2021] and [Stolze et al. 2021] the result of composition is a well-formed protocol.\n\nAuthors’ addresses: Lorenzo Gheri, University of Oxford, United Kingdom, lorenzo.gheri@cs.ox.ac.uk; Nobuko Yoshida, University of Oxford, United Kingdom, nobuko.yoshida@cs.ox.ac.uk.\n\n2018. 2475-1421/2018/1-ART1 $15.00\nhttps://doi.org/\nThis paper presents hybrid multiparty session types: a novel, general theory that offers compositionality for distributed protocol specification, improves on the state of the art, and is immediately compatible with existing multiparty session types systems.\n\nMultiparty session types (MPST) [Coppo et al. 2015; Honda et al. 2016; Yoshida and Gheri 2020] provide a typing discipline for message-passing concurrency, ensuring deadlock freedom for two or more distributed processes. A global type or protocol, which describes an entire interaction scenario, is projected into a collection of local types onto the respective participants (endpoint projection). MPST cater for the safe implementation of distributed processes: as long as the process for each participant is independently type-checked against its local type, its communication behaviour is disciplined by the semantics of the global type, and its execution does not get stuck.\n\nAlthough alternatives to the top-down approach (i.e., endpoint projection from a global type) have been proposed [Deniélou and Yoshida 2013; Lange et al. 2015; Lange and Yoshida 2019; Scalas and Yoshida 2019], the benefits of an explicit, concise design of the communication protocol for the whole system have been recognised by the research community, since the first appearance of MPST [Honda et al. 2008], until more recent times, e.g., see [Cledou et al. 2022; Glabbeek et al. 2021]. Furthermore, the top-down approach has been extended, e.g., to fault tolerance [Viering et al. 2021], timed specification [Bocchi et al. 2014], refinements [Gheri et al. 2022; Zhou et al. 2020], cost awareness [Castro-Perez and Yoshida 2020], exception handling [Lagaillardie et al. 2022], or explicit connections and delegation [Castellani et al. 2020; Hu and Yoshida 2017].\n\nConcretely, the underlying assumption to top-down MPST systems is that a single designer has full knowledge of the communication protocol and can give its formal specification in terms of a global type. Distributed systems, however, are designed modularly, by multiple designers. Recently, the literature has addressed the problem of obtaining a single coherent global type from independently specified subprotocols (components of a protocol) and some solutions have been offered: Barbanera et al. [2021] achieve direct composition of two global types, through a dual compatibility relation that matches inputs and outputs, based on gateways [Barbanera et al. 2018, 2019, 2020b]. Stolze et al. [2021] describe a dual methodology beyond gateways, but severely restrict the syntax for global types. In contrast to this approach, our theory substitutes dual compatibility, based only on input/output matching, with the notion of compatibility through projection. Thus, we improve on the state of the art: (1) we can compose more than two subprotocols into a well-formed global type and (2) we retain the full expressiveness of MPST (including recursion and parallel composition). See §6 for a broader, in-detail discussion. Moreover, metatheoretical results about the semantics of traditional MPST systems [Deniélou and Yoshida 2013; Honda et al. 2016] immediately translate to ours (semantics preservation): from distributed specifications in terms of subprotocols, our theory synthesises a global protocol for the whole system; we prove once and for all, as a metatheoretical result, that such global protocol is a traditionally well-formed global type.\n\nContributions. This paper develops a theory of compositionality for distributed protocol description in MPST systems and introduces the following novel MPST concepts:\n\n- hybrid types, a generalisation of both global and local types, for the specification of communicating subprotocols (Definition 3.3);\n- generalised projection onto sets of roles (Definition 3.6), which well-behaves with respect to set inclusion (Theorem 4.9);\n- localiser (Definition 3.8), a novel operator that isolates, in a subprotocol, the inter-component communication from the intra-component one;\n- compatibility based on projection and localiser (Equation C, §4.1);\nTo the best of our knowledge, our approach is the first that:\n\n- enables the correct composition of two or more subprotocols into a global type, while capturing full MPST expressiveness: branching, parallel composition, and recursion (Corollary 4.10);\n- operates at a purely syntactic level, thus retaining previously developed MPST semantics results (semantics preservation); correctness is guaranteed by compositionality resulting in a traditionally well-formed global type and preserving endpoint projection (Corollary 4.10);\n- provides a notion of compatibility that is more expressive than dual input/output matching and hence suitable for extension to more sophisticated MPST systems (Example 5.7).\n\nWe discuss the applicability and generality of our work, through case studies. (1) We give a distributed specification of the real-world protocol OAuth 2.0 [Hardt 2012], which showcases modularity features of our theory (§5.2) and leads to an optimisation (§5.3, Corollary 5.1). (2) We extend our theory beyond traditional MPST, to delegation and explicit connections (§5.4).\n\nOutline. §2 gives an overview of our development, with a simple, but realistic, application scenario. §3 and §4 are dedicated to our technical contributions. §5 tests the strengths of our theory with case studies. §6 discusses in detail, with examples, related work. §8 concludes with future work. Further detail for definitions and proofs can be found in Appendix B.\n\n2 OVERVIEW OF OUR DEVELOPMENT\n\nThis work achieves distributed protocol specification for MPST: different (protocol) designers specify protocols (naively as global types, Figure 1) for different components of the communicating system; then, these compose into a single global type for the whole system. Composition must preserve (endpoint) projection (indicated with ↓): local types, for the distributed implementation of roles (or participants), need to be obtained by projection of each separate component, but, also, they need to be projections of the same global type (obtained by composition), if we want semantic guarantees (e.g., deadlock freedom) to hold. In other words, our protocol-compositionality theory relies on multiparty compatibility, guaranteed by a well-formed global type, and on semantics proofs from previous work (e.g., [Deniélou and Yoshida 2013]). This approach makes our development semantics-preserving: it endows existing MPST systems with distributed protocol specification.\n\nTraditionally, a global type is a “closed” standalone entity that describes a one-component communication protocol: all interactions among participants are internal to such component. We consider instead the distributed specification of a system, in terms of multiple components (disjoint sets of participants). Each participant can send both internal messages, within its component, or external, to other components. Therefore, we “open” the syntax of global types, so that it allows not only for intra-component communication, but also for inter-component communication. By extending the syntax of global types with an interface for inter-component communication, we obtain hybrid types. The communication protocol of each component of the system is specified as\n\\[ G_{str} = d \\rightarrow \\text{ad} : \\text{prod}(\\text{nat}).d \\rightarrow \\text{ad} : \\{ \\text{ok}.\\text{end}, \\text{stop}.\\text{end} \\} \\]\n\\[ G_{sales} = s \\rightarrow w : \\{ \\text{publish}.\\text{end}, \\text{stop}.\\text{end} \\} \\]\n\\[ G_{fin} = f_1 \\rightarrow f_2 : \\text{prod}(\\text{nat}).f_2 \\rightarrow f_1 : \\{ \\text{price}(\\text{nat}).\\text{end}, \\text{stop}.\\text{end} \\} \\]\n\n(a) Global Types for Internal Communication\n\n\\[ H'_{str} = d \\rightarrow \\text{ad} : \\text{prod}(\\text{nat}).d!s : \\text{prod}(\\text{nat}) . d!f_1 : \\text{prod}(\\text{nat}) . d \\rightarrow \\text{ad} : \\{ \\text{ok}.\\text{end}, \\text{stop}.\\text{end} \\} \\]\n\\[ H'_{sales} = d?s : \\text{prod}(\\text{nat}).s \\rightarrow w : \\{ \\text{publish}.\\text{end}, \\text{stop}.\\text{end} \\} \\]\n\\[ H'_{fin} = d?f_1 : \\text{prod}(\\text{nat}) . f_1 \\rightarrow f_2 : \\text{prod}(\\text{nat}) . f_2 \\rightarrow f_1 : \\{ \\text{price}(\\text{nat}).\\text{end}, \\text{stop}.\\text{end} \\} \\]\n\n(b) Hybrid Types for Basic Inter-Department Interactions\n\n\\[ H_{str} = d \\rightarrow \\text{ad} : \\text{prod}(\\text{nat}).d!s : \\text{prod}(\\text{nat}).d!f_1 : \\text{prod}(\\text{nat}).\\mu X.f_1 ?d : \\{ \\text{ok}.d \\rightarrow \\text{ad} : \\text{go}.\\text{end}, \\text{wait}.d \\rightarrow \\text{ad} : \\text{wait}.X \\} \\]\n\\[ H_{sales} = d?s : \\text{prod}(\\text{nat}).\\mu X.f_1 ?s : \\{ \\text{price}(\\text{nat}).s \\rightarrow w : \\text{publish}.\\text{end}, \\text{wait}.s \\rightarrow w : \\text{wait}.X \\} \\]\n\\[ H_{fin} = d?f_1 : \\text{prod}(\\text{nat}) . f_1 \\rightarrow f_2 : \\text{prod}(\\text{nat}) . \\mu X.f_2 \\rightarrow f_1 : \\{ \\text{price}(\\text{nat}).f_1 !d : \\text{ok}.f_1 !s : \\text{price}(\\text{nat}).\\text{end}, \\text{wait}.f_1 !d : \\text{wait}.f_1 !s : \\text{wait}.X \\} \\]\n\n(c) More Expressive Hybrid Types\n\nFig. 2. Types for Interactions in the Company\n\na hybrid type; multiple components can be composed into a well-formed global type thanks to a novel notion of compatibility, based on projection.\n\nIn what follows: we consider a three-component system: a company with three departments, for each of which, a different (protocol) designer is in charge of describing the communication protocol. The departments, with respective (internal) roles, are the following: (a) the strategy team, the roles of which are the director \\( d \\) of the company and the advertisement team \\( \\text{ad} \\); (b) the sales department, with a salesman \\( s \\) and the website administrator \\( w \\); (c) the finance department, with two employees, \\( f_1 \\) and \\( f_2 \\). We assume that internal roles of different components are distinct.\n\n**Global Types for Intra-Component Communication.** When no inter-component communication happens, each protocol designer gives a global type for the internal communication of their department (Figure 2a). In \\( G_{str} \\), the global type for the strategy department, the director \\( d \\) sends the product ID to the responsible for advertisement \\( \\text{ad} \\); then, \\( d \\) gives an ok or asks \\( \\text{ad} \\) to stop. For the sales department \\( G_{sales} \\) \\( s \\) decides whether \\( w \\) can publish some content on the company website. In the financial department \\( G_{fin} \\), \\( f_1 \\) sends the product ID to \\( f_2 \\) and gets back either a price or a stop.\n\n**Hybrid Types for Inter-Component Interactions.** The components of a distributed system are expected to communicate with each other. Therefore, we introduce a hybrid syntax of global and local constructs (and we call hybrid types the terms of this syntax): to the global-type syntax (e.g., \\( d \\rightarrow \\text{ad} \\)), for intra-component communication, we add local send and receive constructs (e.g., \\( d!s \\) and \\( d?f_1 \\)), as the interface for inter-component communication. In our example, a first message is sent by \\( d \\), with a product ID \\( prod \\), externally, to the other two departments (Figure 2b): \\( d!s \\) and \\( d?f_1 \\). These are dually received by the sales team \\( d?s \\) and by the finance team \\( d?f_1 \\), respectively (as highlighted in Figure 2b).\n\n**Remark 2.1 (Generalising Global and Local Types).** We observe that hybrid types are a generalisation of both global and local types. A global type is a “closed” hybrid type, where only internal messages are exchanged. The intuition for local types is more subtle: a local type can be interpreted...\nas a basic, one-participant component of a communicating system, which communicates only externally, with participants of other components. E.g., the local type $?p.q.q; f_1.q; r; f_2.end$, for the participant $q$, can be written as the hybrid type $p?q.q; f_1.q; q; r; f_2.end$: $q$ is the only internal participant that first receives from $p$ and then sends to $r$ (both $p$ and $r$ are of other components). Being able to express global and local types as hybrid types is fundamental: it makes our results correct and compatible with existing MPST theories (see Remark 2.2 below, and Corollary 4.10 in §4).\n\n**Expressiveness and Compatibility.** We describe a more expressive version of the protocols (Figure 2c) that combines inter-component messages with branching and recursion. Figure 3 shows the communication for each component of the system, as described by the protocol designer of each department. We imagine that the price of the product $prod$ is decided within the finance department: the finance expert $f_2$ either gives a price or asks all processes to wait in a recursive loop; then, the decision is communicated to the other departments. Figure 3c shows the execution of the protocol for the finance department, where $f_2$ makes such choice. Figure 2c shows the formal specifications, as hybrid types, of the three protocols. We observe that, to compose $H_{str}, H_{sales},$ and $H_{fin}$ (and, in general, to compose, more than two communicating protocols), dual relations are not sufficient for compatibility (for a broader discussion see §6). Our proposal is to give separately the specification of a communication discipline for inter-component interactions only: intra-component interactions are left to the designer of each respective component and some chief designer gives the description of one more protocol, for global guidance of inter-component communication. For our example, we collect all the interactions between any two different departments in the protocol in Figure 4a, and we formalise it with a compatibility (global) type:\n\n$$G^\\dagger := d \\rightarrow s : prod(nat).d \\rightarrow f_1 : prod(nat).\\mu X.f_1 \\rightarrow d : \\begin{cases} ok.f_1 \\rightarrow s : price(nat).end, \\\\ wait.f_1 \\rightarrow s : wait.X \\end{cases}$$\n\nCompatibility of subprotocols $H_{str}, H_{sales},$ and $H_{fin},$ with $G^\\dagger$, is achieved by asking that the (generalised) projection $\\uparrow$, of $G^\\dagger$, with respect to the internal participants of each subprotocol, is equal to the localisation loc, of that subprotocol, where “localising a protocol” means isolating its inter-component communication (by retaining only its local constructs). E.g., we consider $H_{str}$ and its internal participants $\\{d, ad\\}$.\n\n$$G^\\dagger \\uparrow_{\\{d,ad\\}} = loc H_{str} = d : s : prod(nat).d : f_1 : prod(nat).\\mu X.f_1 : d : \\{ok.end, wait.X\\}$$\n\nAnalogously we require that $G^\\dagger \\uparrow_{\\{s,ad\\}} = loc H_{sales}$ and $G^\\dagger \\uparrow_{\\{f_1,f_2\\}} = loc H_{fin}$.\n\nWe observe that not only we have enriched the syntax of global types with local constructs to get hybrid types, but also we have generalised projection to sets of participants, introduced a new operator (localiser) to isolate external communication, and, based on these, defined compatibility.\n\n**Compositionality and Correctness.** Our theory (§3 and §4) provides an explicit function $B$ that builds back a single global type for the communication in the company, from the distributed specification above: $G = B(G^\\dagger)([H_{str}, H_{sales}, H_{fin}])$. It holds that $G \\uparrow_d = H_{str} \\uparrow_d$, $G \\uparrow_{f_1} = H_{fin} \\uparrow_{f_1}$, and analogously for all participants: projection is preserved. A figure, representing such $G$ for our example, can be found in Appendix A.\n\nMore generally (see Figure 4b), from a compatibility type $G^\\dagger$ and hybrid types $H_i$ for each component (with set of internal participants $E_i$), such that they are compatible $G^\\dagger \\uparrow_{E_i} = loc H_i$, our theory synthesises a global type $G = B(G^\\dagger)([H_1, \\ldots, H_n])$ (Definition 4.6 and Theorem 4.7). Correctness of our theory is given by Corollary 4.10. Formally, this result guarantees that the local types, projections of $G$ on each participant, are the same as if obtained by the respective subprotocol $H_i; G \\uparrow_p = H_i \\uparrow_p$ if $p$ is a participant of the $i$-th subprotocol $H_i$. We have achieved distributed protocol specification: we can both obtain local types for implementation in a distributed fashion, by projection of the respective component $H_i$ (no designer or programmer needs the full knowledge of\nG), and rest assured that all local types (for all participants, in all components) are projections of a single, well-formed global type. This makes our development compatible with existing MPST theories, with no need for developing new semantics (semantics preservation): a well-formed global type projecting on all participants gives traditional multiparty compatibility, which, thanks to the semantics results in the literature [Coppo et al. 2015; Deniélou and Yoshida 2013; Honda et al. 2016], leads to guarantees, such as liveness and deadlock freedom.\n\nRemark 2.2 (Hybrid Types and Generalised Projection). With reference to Figure 4b, Let us consider the set of participants \\( E_i \\) of the generic \\( H_i \\), and \\( p \\in E_i \\). Generalised projection takes a hybrid type and returns a hybrid type; since global and local types are hybrid types (Remark 2.1), e.g., we can project \\( G^\\dagger \\) onto \\( E_i \\) for compatibility \\( (G^\\dagger \\upharpoonright_{E_i} = \\text{loc } H_i) \\), or \\( G \\) onto \\( E_i \\) and verify that it is equal to \\( H_i \\) (see Theorem 4.7, §4). Most importantly, Theorem 4.9 in §4 guarantees that projection composes over set inclusion \\( G^\\dagger \\upharpoonright_p = (G^\\dagger \\upharpoonright_{E_i}) \\upharpoonright_p = H_i \\upharpoonright_p \\) by projecting \\( H_i \\) and \\( G \\) onto the participant \\( p \\), we obtain the same local type for \\( p \\). Namely, we can obtain local types from the specific component \\( H_i \\) and then implement them in a distributed fashion, but also they all are projections of a well-formed global type \\( G \\).\n\nTo summarise (see Figure 4b), our proposal for distributed protocol specification is the following:\n\n1. a different designer specifies, for each component of the system, a hybrid type \\( H_i \\);\n2. a chief designer gives the compatibility type \\( G^\\dagger \\) to discipline inter-component interactions;\n3. compatibility is a simple equality check: \\( G^\\dagger \\upharpoonright_{E_i} = \\text{loc } H_i \\) (\\( E_i \\) is the set of participants for \\( H_i \\)).\n\nIn return, as a metatheoretical result proved once and for all by our theory, the designers obtain \\( \\mathcal{B} (G^\\dagger) (\\{H_1, \\ldots, H_n\\}) \\), a global type for the whole communication, for which projections are preserved (and, hence, MPST semantic guarantees hold).\n\nIn §3 and §4 we detail our compositionality theory, including generalised projection, localiser, compatibility, build-back, and correctness results.\n\n---\n\nFig. 3. Communication for Each Department in the Company\n### 3 Hybrid Types for Protocol Specification\n\n#### 3.1 Background: Preliminaries of Multiparty Session Types\n\nWe give a short summary of multiparty session types [Coppe et al. 2015; Honda et al. 2016; Scalas et al. 2019; Yoshida and Gheri 2020]; specifically, our theory is based on the formulation in [Denielou and Yoshida 2013], extended to parallel composition of global types. The notation for our MPST system is standard (directly adapted from [Castro-Perez et al. 2021]).\n\nAtoms of our syntax are: a set of roles (or participants), ranged over by $p, q, \\ldots$, a set of (type) variables, ranged over by $X, Y, \\ldots$, and a set of labels, ranged over by $\\ell_0, \\ell_1, \\ldots, \\ell_i, \\ell_j, \\ldots$.\n\n**Definition 3.1 (Sorts, Global Types, and Local Types).** Sorts, global types, and local types, ranged over by $S, G$, and $L$ respectively, are inductive datatypes generated by:\n\n- $S ::= \\text{unit} | \\text{nat} | \\text{int} | \\text{bool} | S+S | S*S$\n- $G ::= \\text{end} | X | \\mu X. G | p \\rightarrow q : \\{\\ell_i(S_i).G_i\\}_{i \\in I} | G_1 | G_2$\n- $L ::= \\text{end} | X | \\mu X. L | ![q; \\ell_i(S_i).L_i]_{i \\in I} | ![p; \\ell_i(S_i).L_i]_{i \\in I}$\n\nwhere, $p \\neq q$, $I \\neq \\emptyset$, and $\\ell_i \\neq \\ell_j$ when $i \\neq j$, for all $i, j \\in I$, in $p \\rightarrow q : \\{\\ell_i(S_i).G_i\\}_{i \\in I}, ![q; \\ell_i(S_i).L_i]_{i \\in I}$, and $![p; \\ell_i(S_i).L_i]_{i \\in I}$.\n\nThe global message $p \\rightarrow q : \\{\\ell_i(S_i).G_i\\}_{i \\in I}$ describes a protocol where participant $p$ sends to $q$ one message with label $\\ell_1$ and a value of sort $S_1$ as payload, for some $i \\in I$; then, depending on which $\\ell_i$ was sent by $p$, the protocol continues as $G_i$. The type $\\text{end}$ represents a terminated protocol. Recursive protocol is modelled as $\\mu X. G$, where recursion variable $X$ is bound. The parallel construct $G_1 | G_2$ describes a protocol composed by two independent ones. The participants of $G_1$ and $G_2$ are required to be disjoint: no communication happens between $G_1$ and $G_2$, but only internally in each one of them (for a broader discussion, see §5.1). The intuition for local types $\\text{end}$, $X$ and $\\mu X. L$ is the same as for global types. The send type $![q; \\ell_i(S_i).L_i]_{i \\in I}$ says that the participant implementing the type must choose a labelled message to send to $q$; if the participant chooses the label $\\ell_i$, it must include in the message to $q$ a payload value of sort $S_i$, and continue as prescribed by $L_i$. The receive type $![p; \\ell_i(S_i).L_i]_{i \\in I}$ requires to wait to receive a value of sort $S_i$ (for some $i \\in I$) from the participant $p$, via a message with label $\\ell_i$; then the process continues as prescribed by $L_i$.\n\nWe are interested in types that are (1) guarded—e.g., $\\mu X. p \\rightarrow q : ![\\ell_i(\\text{nat})].X$ is a valid global type, whereas $\\mu X.X$ is not—(detail in Appendix B.1, Definition B.1) and (2) closed, i.e., all variables are bound by $\\mu X$. In messages, sends and receives, the payload type can be omitted (e.g., $p \\rightarrow q : ![\\ldots]$), when only a label is exchanged. We assume that global and local types are always guarded, and that, in $G_1 | G_2, G_1$ and $G_2$ are closed.\nProjection plays a central role in MPST theories: it connects the protocol discipline, provided by the global type, with the local types that separately describe the behaviour of each participant.\n\nDefinition 3.2 (Projection for Global Types). The projection of a global type onto a role \\( r \\) is a partial function defined by recursion on \\( G \\), whenever the recursive call is defined:\n\n\\[\n\\text{[proj-end]} \\quad \\text{end} \\triangleright r = \\text{end} \\quad \\text{[proj-var]} \\quad X \\triangleright r = X \\\\\n\\text{[proj-rec]} \\quad (\\mu X.G) \\triangleright r = \\mu X.(G \\triangleright r) \\quad \\text{if \\( \\mu X.(G \\triangleright r) \\) is guarded, else, if \\( (\\mu X.G) \\triangleright r = \\text{end} \\)} \\\\\n\\text{[proj-par]} \\quad G_1 \\uplus G_2 \\triangleright r = G_i \\triangleright r \\quad \\text{if \\( r \\) is a participant of \\( G_i \\), end otherwise} \\\\\n\\text{[proj-send]} \\quad p \\rightarrow q : \\{t_i(S_i).G_i\\}_{i \\in I} \\triangleright r = !q : \\{t_i(S_i).G_i \\triangleright r\\}_{i \\in I} \\quad \\text{if \\( r = p \\)} \\\\\n\\text{[proj-recv]} \\quad p \\rightarrow q : \\{t_i(S_i).G_i\\}_{i \\in I} \\triangleright r = ?p : \\{t_i(S_i).G_i \\mid r\\}_{i \\in I} \\quad \\text{if \\( r = q \\)} \\\\\n\\text{[proj-merge]} \\quad p \\rightarrow q : \\{t_i(S_i).G_i\\}_{i \\in I} \\triangleright r = \\bigcup_{i \\in I}(G_i \\triangleright r) \\quad \\text{if \\( r \\neq p \\) and \\( r \\neq q \\)}\n\\]\n\n\\( G \\triangleright r \\) is undefined if none of the above applies. Merging (\\( \\uplus \\)) is defined as a partial operator over two local types such that: \\( L \\uplus L = L \\) for every type, it delves inductively inside all constructors (e.g., \\( !q : \\{t_i(S_i).L_i\\}_{i \\in I} \\uplus \\uplus !q : \\{t_i(S_i).L'_i\\}_{i \\in I} = !q : \\{t_i(S_i).(L_i \\uplus L'_i)\\}_{i \\in I} \\)), and \\( ?p : \\{t_i(S_i)L_i\\}_{i \\in I} \\uplus \\uplus ?p : \\{t_j(S_j)L'_j\\}_{j \\in J} = ?p : \\{t_k(S_k).L_k \\uplus L'_k\\}_{k \\in K \\cap I} \\cup \\{t_k(S_k).L_k\\}_{k \\in K \\setminus I} \\cup \\{t_k(S_k).L'_k\\}_{k \\in K \\setminus J} \\).\n\nWe describe the clauses of Definition 3.2. [proj-end], [proj-var], and [proj-rec] are standard. [proj-send] (resp. [proj-recv]) states that a global type starting with a message from \\( r \\) to \\( q \\) (resp. from \\( p \\) to \\( r \\)) projects onto a sending (resp. receiving) local type \\( !q : \\{t_i(S_i).G_i \\triangleright r\\} \\) (resp. \\( ?p : \\{t_i(S_i).G_i \\triangleright r\\} \\)), provided that the continuations \\( G_i \\triangleright r \\) are also projections of the corresponding global-type continuations \\( G_i \\). [proj-merge] states that, if the projected global type starts with an interaction between \\( p \\) and \\( q \\), and if we are projecting it onto a third participant \\( r \\), then the projection is defined (and we can skip the message \\( p \\rightarrow q \\) : ) if all the continuations project onto mergeable types (according to the merge operator \\( \\uplus \\) defined above). [proj-par] states that projecting a parallel type \\( G_1 \\mid G_2 \\) on \\( r \\) is the same as projecting \\( G_1 \\) or \\( G_2 \\) onto \\( r \\), depending on whether \\( r \\) is a participant of one or the other type.\n\nBy projecting a global type \\( G \\) onto all participants \\( (G \\triangleright r) = L_r \\), for the generic role \\( r \\), we obtain a collection of local types \\( \\{L_r\\} \\), where \\( L_r \\) is the behavioural type for \\( r \\). Existing MPST theories (e.g., [Deniélou and Yoshida 2013]) guarantee that a session of well-typed implementations of the participants inherits semantic guarantees for its communication, from \\( G \\). Our development in §4 is compatible with such theories: result of composition is a well-formed \\( G \\), thus, implementations of projected local types benefit from well-established semantics results from the literature.\n\n3.2 Hybrid Types\n\nTo allow the specification of interacting subprotocols, we enrich the syntax of global types with local constructs. We thus obtain \"hybrid\" types, which use global messages for intra-protocol communication and local sends and receives as openings for inter-protocol communication.\n\nDefinition 3.3 (Hybrid Types). Hybrid types are defined inductively by:\n\n\\[\n\\text{H := end} \\triangleright X \\mid \\mu X.H \\mid H_1[H_2 \\mid p\\|q : \\{t_i(S_i).H_i\\}_{i \\in I} \\mid p \\| q : \\{t_i(S_i).H_i\\}_{i \\in I} \\mid p \\rightarrow q : \\{t_i(S_i).H_i\\}_{i \\in I}\n\\]\n\nwhere, in \\( p \\rightarrow q : \\{t_i(S_i).H_i\\}_{i \\in I} \\), \\( p\\|q : \\{t_i(S_i).H_i\\}_{i \\in I} \\), and \\( p\\|q : \\{t_i(S_i).H_i\\}_{i \\in I} \\), \\( p \\neq q, I \\neq \\emptyset \\), and \\( i \\neq j \\)\nwhen \\( i \\neq j \\), for all \\( i, j \\in I \\). We indicate the datatype of hybrid types with the notation \\( \\mathcal{H} \\).\n\nThe intuition behind each construct is the same as in Definition 3.1, but we write \\( p\\|q : \\{t_i(S_i).H_i\\}_{i \\in I} \\) in place of \\( !q : \\{t_i(S_i).L_i\\}_{i \\in I} \\), and \\( p\\|q : \\{t_i(S_i).H_i\\}_{i \\in I} \\) in place of \\( ?p : \\{t_i(S_i).L_i\\}_{i \\in I} \\). For local types, \\( !q : \\{t_i(S_i).L_i\\}_{i \\in I} \\) (resp. \\( ?p : \\{t_i(S_i).L_i\\}_{i \\in I} \\)) describes the communication of the participant \\( p \\) sending a message to \\( q \\) (resp. \\( q \\) receiving a message from \\( p \\)), and then continuing with interactions all involving \\( p \\) (resp. \\( q \\)) as a subject. Therefore, such subject can be left implicit. For hybrid types, instead, different (internal) subjects interact both with internal and external participants. For instance:\n(a) \\( p \\mid q \\mid \\ell_1 \\). (b) \\( p \\rightarrow r \\mid \\ell_2 \\). (c) \\( q ? r \\mid \\ell_3 \\). (d) end\n\n(a) \\( p \\) sends an external message to \\( q \\); (b) \\( p \\) exchanges a message internally with \\( r \\); (c) \\( r \\) receives an external message from \\( q \\); and (d) the protocol terminates.\n\n**Definition 3.4 (Internal and External Participants).** We define the sets of internal participants and external participants of a hybrid type \\( H \\) by recursion:\n\n\\[\n\\text{ipart}(\\text{end}) = \\emptyset \\quad \\text{ipart}(X) = \\emptyset \\\\\n\\text{ipart}(\\mu X \\cdot H) = \\text{ipart}(H) \\\\\n\\text{ipart}(H_1 | H_2) = \\text{ipart}(H_1) \\cup \\text{ipart}(H_2) \\\\\n\\text{ipart}(p \\mid q; \\{t_i(S_i).H_i\\}_{i \\in I}) = \\{p\\} \\cup \\bigcup_{i \\in I} \\text{ipart}(H_i) \\\\\n\\text{ipart}(p?q; \\{t_i(S_i).H_i\\}_{i \\in I}) = \\{q\\} \\cup \\bigcup_{i \\in I} \\text{ipart}(H_i) \\\\\n\\text{ipart}(p \\rightarrow q; \\{t_i(S_i).H_i\\}_{i \\in I}) = \\{p, q\\} \\cup \\bigcup_{i \\in I} \\text{ipart}(H_i) \\\\\n\\text{epart}(\\text{end}) = \\emptyset \\quad \\text{epart}(X) = \\emptyset \\\\\n\\text{epart}(\\mu X \\cdot H) = \\text{epart}(H) \\\\\n\\text{epart}(H_1 | H_2) = \\text{epart}(H_1) \\cup \\text{epart}(H_2) \\\\\n\\text{epart}(p \\mid q; \\{t_i(S_i).H_i\\}_{i \\in I}) = \\{p \\mid q; \\{t_i(S_i).H_i\\}_{i \\in I}\\} \\\\\n\\text{epart}(p?q; \\{t_i(S_i).H_i\\}_{i \\in I}) = \\emptyset \\\\\n\\text{epart}(p \\rightarrow q; \\{t_i(S_i).H_i\\}_{i \\in I}) = \\emptyset\n\\]\n\nWe define, for hybrid types, guardedness and closedness, as for global and local types (Definition 3.1). We require that all hybrid types in this paper are guarded (detail in Appendix B.1, Definition B.1) and that, for all \\( H \\), \\( \\text{ipart}(H) \\cap \\text{epart}(H) = \\emptyset \\). Also, we require well-formedness for parallel constructs: for \\( H_1 | H_2, H_1 \\) and \\( H_2 \\) must be closed and \\((\\text{ipart}(H_1) \\cup \\text{epart}(H_1)) \\cap (\\text{ipart}(H_2) \\cup \\text{epart}(H_2)) = \\emptyset \\). Namely, the parallel construct describes communication that happens independently, within two separate groups of participants. We express globally limited local types in terms of hybrid types, with two predicates on \\( \\mathcal{H}: \\text{isGlobal}(H) \\) holds iff \\( H \\) is formed only by global constructs (global type syntax in Definition 3.1); and \\( \\text{isLocal}(H) \\) holds iff \\( \\text{ipart}(H) \\) contains at most one element (hence \\( H \\) contains only local constructs, see local types in Definition 3.1).\n\n**Example 3.5.** We use as a recurring example the company from §2. A designer, \\( D_{\\text{str}} \\), describes the protocol \\( H_{\\text{str}} \\) for the strategic team, as in Figure 2c:\n\n\\[\nH_{\\text{str}} := d \\rightarrow ad : \\text{prod}(nat) \\cdot d!s : \\text{prod}(nat) . d!f_1 : \\text{prod}(nat) . \\mu X . f_1 ? d : \\{ \\text{ok} . d \\rightarrow ad : \\text{go}, \\text{end} , wait . d \\rightarrow ad : \\text{wait} . X \\}\n\\]\n\nFirst, \\( d \\) sends internally a product ID to \\( ad \\), then a similar external message to \\( s \\), of the sales department, and to \\( f_1 \\), of the finance department. \\( d \\) waits in a recursive loop for \\( f_1 \\) to give the \\( \\text{ok} \\). When this happens, \\( d \\) internally communicates to \\( ad \\) that they can proceed with the product advertisement. For \\( H_{\\text{str}} \\), the sets of internal and external participants are \\( \\text{ipart}(H_{\\text{str}}) = \\{d, ad\\} \\) and \\( \\text{epart}(H_{\\text{str}}) = \\{s, f_1\\} \\). We observe that \\( D_{\\text{str}} \\) is not concerned with the communication that happens internally to the sales department or the financial one, nor with the communication between these two. Designers \\( D_{\\text{sales}} \\) and \\( D_{\\text{fin}} \\) independently give protocols for the sales and financial departments respectively (as in Figure 2c):\n\n\\[\nH_{\\text{sales}} = d!s : \\text{prod}(nat) . \\mu X . f_1 ? s : \\{ \\text{price} . nat . s \\rightarrow w : \\text{publish} . nat . \\text{end} , wait . s \\rightarrow w : \\text{wait} . X \\}\n\\]\n\n\\[\nH_{\\text{fin}} = d!f_1 : \\text{prod}(nat) . f_1 \\rightarrow f_2 : \\text{prod}(nat) . \\mu X . f_2 \\rightarrow f_1 : \\{ \\text{price} . nat . f_1 ! d : \\text{ok} . f_1 ! s : \\text{price} . nat . \\text{end} , wait . f_1 ! d : \\text{wait} . f_1 ! s : \\text{wait} . X \\}\n\\]\n\nIn the sales department, once \\( d \\) has communicated the product, \\( s \\) waits in a loop for the decision about the price from the financial department, then gives to the website administrator \\( w \\) the command to publish. We have that \\( \\text{ipart}(H_{\\text{sales}}) = \\{s, w\\} \\) and \\( \\text{epart}(H_{\\text{sales}}) = \\{d, f_1\\} \\). The decision about the price of the product is taken by \\( f_2 \\), and communicated internally to the financial department with \\( f_2 \\rightarrow f_1 \\); then \\( f_1 \\) communicates the decision to the other departments, which can continue with their internal communication. We have that \\( \\text{ipart}(H_{\\text{fin}}) = \\{f_1, f_2\\} \\) and \\( \\text{epart}(H_{\\text{fin}}) = \\{d, s\\} \\).\n\nIn §4, we prove the above types compatible and compose them into a single global type.\n### 3.3 Projection and Localiser\n\nWe introduce projection and localiser for hybrid types. These operators play an important role in defining compatibility and, ultimately, achieving compositionality.\n\n**Definition 3.6 (Projection).** The (generalised) projection of a hybrid type on the set of participants $E$, is a partial operator, $\\_ \\mid_E : \\mathcal{H} \\rightarrow \\mathcal{H}$, recursively defined by the following clauses (whenever the recursive call is defined):\n\n- **[proj-send]** end $\\mid_E =$ end\n- **[proj-var]** $X \\mid_E = X$\n- **[proj-rec]** $\\mu X.H \\mid_E = \\mu X.(H \\mid_E)$ if $\\mu X.(H \\mid_E)$ is guarded, else, if $(\\mu X.H)$ is closed, $(\\mu X.H) \\mid_E =$ end\n- **[proj-par]** $H_1 \\mid_{E \\cup E} = H_1 \\mid_E$\n- **[proj-msg]** $p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\mid_{E \\cup \\{p\\}} = p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I}$ if $p, q \\in E$ and $q \\notin E$\n- **[proj-reacv]** $p \\mid_{E \\cup \\{q\\}} : \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\mid_{E \\cup \\{p\\}} = p \\mid_{E \\cup \\{q\\}} : \\{\\ell_i(S_i).H_i\\}_{i \\in I}$ if $p \\notin E$ and $q \\in E$\n- and undefined otherwise.\n\n**Merging** ($\\cup$) is defined as a partial commutative operator over two hybrid types such that: for all $H, H \\cup H' = H$, it delves inductively inside all constructors (e.g., $p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I} = p \\rightarrow q : \\{\\ell_j(S_j).H_j\\}_{j \\in J}$).\n\nWith respect to Definition 3.2, we now allow projection onto a set of participants, the introduces rules for projecting send and receive constructs. We highlight the differences below:\n\n- **[proj-send]** defines $p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I}$ to be projected onto $E$, if both $p \\in E$ and $q \\notin E$; in this case the structure of the global message $p \\rightarrow q$ is maintained in the projected type;\n- **[proj-var]** defines projection when the sender $p$ is in $E$ and $q$ is not, and when both $p, q \\notin E$;\n- **[proj-reacv]** defines projection when the receiver $q$ is in $E$ and $p$ is not, and when both $p, q \\notin E$.\n\n**Remark 3.7.** Projection is defined only onto sets of internal participants, e.g., $p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I}$ can be projected onto $q$, but not onto $p$; also, $\\text{ipart}(H \\mid E) \\subseteq \\text{ipart}(H)$. If we project a hybrid type onto a singleton, we obtain a local type: $\\text{isLocal}(H \\mid \\{p\\})$. Furthermore, if $\\text{isGlobal}(H)$, then $H \\mid \\{p\\}$ is exactly the traditional MPST projection of the global type $H$ onto $p, H \\mid \\{p\\}$ (Definition 3.2).\n\n**Definition 3.8 (Localiser).** The localiser of a hybrid type is a partial operator, $\\_ \\mid : \\mathcal{H} \\rightarrow \\mathcal{H}$, recursively defined by the following clauses (whenever the recursive call is defined):\n\n- **[loc-send]** end $\\mid =$ end\n- **[loc-var]** $X \\mid = X$\n- **[loc-rec]** $\\mu X.H \\mid = \\mu X.(H \\mid)$\n- **[loc-par]** $H_1 \\mid \\{H_2\\} = H_1 \\mid H_2$\n- **[loc-msg]** $p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\mid_{\\{p\\}} = p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I}$ if $p, q \\in E$\n- **[loc-reacv]** $p \\mid_{\\{q\\}} : \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\mid_{\\{p\\}} = p \\mid_{\\{q\\}} : \\{\\ell_i(S_i).H_i\\}_{i \\in I}$ if $p \\notin E$ and $q \\in E$\n- and undefined otherwise.\n\n**Merging** ($\\cup$) is a partial commutative operator over two hybrid types such that: for all $H, H' \\cup H = H'$, it delves inductively inside all constructors (e.g., $p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\cup p \\rightarrow q : \\{\\ell_i(S_i).H'_i\\}_{i \\in I} = p \\rightarrow q : \\{\\ell_k(S_k).H_k \\cup H'_k\\}_{k \\in I \\cup J} \\cup \\{\\ell_k(S_k).H'_k\\}_{k \\in I \\cup J}$).\nThe localiser is a forgetful operator that preserves local constructs and discards global messages. \\([\\text{loc-end}], \\text{loc-var}, \\text{loc-rec}, \\text{and loc-par}\\) preserve the non-message structure of the type, into its localisation. \\([\\text{loc-send}]\\) and \\([\\text{loc-receiv}]\\) state that send construct (an internal participant \\(p\\) sends to an external participant \\(q\\)) and receive construct (an internal participant \\(q\\) receives from an external participant \\(p\\)) are to be maintained and their continuations \\(H_i\\) localised into loc \\(H_i\\). \\([\\text{loc-msg}]\\) is the central rule: each global message has to be skipped and its continuations need to be merged.\n\nRemark 3.9. The merge operator for the localiser, \\(\\sqcup^L\\), is dual to the merge for projection, \\(\\sqcup\\). To build the intuition behind this, let us consider the following hybrid type: \\(H = p \\rightarrow q : \\{\\ell_1.p!r;\\ell_1.end, \\ell_2.p!r;\\ell_2.end\\}\\). First, \\(p\\) chooses on which branch to take, by internally sending either \\(\\ell_1\\) or \\(\\ell_2\\) to \\(q\\); then according to the chosen branch, \\(p\\) itself sends a different external message to \\(r\\). When we localise the above type we obtain loc \\(H = p!r;\\{\\ell_1.end, \\ell_2.end\\}\\), namely we have merged send constructs with different labels, \\(p!r\\ell_1\\) and \\(p!r\\ell_2\\). From the point of view of the external receiver \\(r\\), it makes no difference whether such choice has been taken by \\(p\\) at the time \\(p\\) sends to \\(r\\) (with \\(p!r\\)), or at a precedent stage of communication, internal to \\(H\\) (with \\(p \\rightarrow q\\)). This intuition is proven correct by the results from the next section, when we define a compatibility notion, based on localiser and projection, and we prove compositionality.\n\n4 COMPOSITIONALITY FOR DISTRIBUTED SPECIFICATION\n\nIn §3, we have set definitions in place to compose subprotocols. In particular, following the overview of Figure 4b, §2, what we need is:\n\n- hybrid types \\(H_1, H_2, \\ldots, H_N\\) for the multiple components of the communicating system;\n- a compatibility hybrid type \\(H^\\dagger\\) (we sometimes use the notation \\(G^\\dagger\\), when \\(H^\\dagger\\) is a global type, namely when \\(\\text{isGlobal}(H^\\dagger)\\)) that disciplines the inter-component communication; and\n- the property that \\(H^\\dagger\\) projects onto the localisations of \\(H_1, H_2, \\ldots, H_N\\) (compatibility).\n\nIn this section, we present our journey to multiparty compositional specification in three steps:\n\n1. we focus on a single hybrid type \\(H_i\\), for which compatibility holds: \\(H^\\dagger \\upharpoonright E_i = \\text{loc } H_i\\); we build a new type \\(B^1_i \\upharpoonright (H^\\dagger) (H_i)\\), whose projection on \\(E_i\\) coincides with \\(H_i\\), and which contains the information for external communication from \\(H^\\dagger\\) (Theorem 4.4);\n\n2. we show how Step 1 is a base case for composing multiple compatible protocols: from \\(B^1_i\\), we recursively define \\(B (H^\\dagger) ([H_1, \\ldots, H_N])\\), which projects onto \\(H_i\\) for all \\(i = 1, \\ldots, N\\) (compositionality, Theorem 4.7);\n\n3. we prove that projection composes over the subset relation (Theorem 4.9); this guarantees the applicability and correctness of our result: if \\(H^\\dagger\\) is a global type, we obtain a well-formed global type \\(G = B (H^\\dagger) ([H_1, \\ldots, H_N])\\) for the whole system, the projections of which, onto every participant, are the same as the projections of the subprotocols \\(H_i\\) (Corollary 4.10).\n\n4.1 Step 1: Building Back a Single Subprotocol\n\nOur first step towards compositionality is also the most technical of the three. In this section we present the main design choices, both in constructions and in proofs, that make our theory sound. For more details, we refer to Appendix B.1.\n\nWe are given \\(H^\\dagger\\), the compatibility type disciplining communication happening among subprotocols, and with one of these subprotocols \\(H^\\dagger\\), describing the communication from the point of view of its internal participants, contained in the set \\(E\\). The local constructs of \\(H^\\dagger\\) are compatible with what prescribed by \\(H^\\dagger\\) for communicating externally, formally:\n\n\\[H^\\dagger \\upharpoonright E = \\text{loc } H^E\\]\nThe above notion is designed for the direct composition of multiple subprotocols: the hybrid type $H^E$ for one component is checked compatible, not against other components, but against $H^T$, which gives global guidance for inter-component communication. This design choice differentiates our theory from previous work, where compatibility is checked by directly matching the inputs and outputs of two separate components (see §6 for further discussion). With such compatible types, we build $H = B_E^1 (H^T) (H^E)$ that retains the information about external communication of $H^T$ and about internal communication in the component $H^E$.\n\n**Definition 4.1 (Build-Back of a Single Component).** Given a set of participants $E$, we define the build-back of a single component as the partial recursive function $B_E^1 (H^T) (H^E)$. The recursive equations are given in Figure 5; if none of those apply or if $\\text{ifart}(H^E) \\not\\subseteq E$, $B_E^1 (H^T) (H^E)$ is undefined.\n\nThe rest of this subsection is dedicated to discussing the intuition behind the function $B_E^1$ and its correctness (Theorem 4.4). First, let us consider the following equations from Definition 4.1:\n\n$$B_E^1 (\\{ p \\rightarrow q : \\{ \\ell_i (S_i) . H_i^T \\} \\}_{i \\in I}) (H^E) = B_E^1 (\\{ p' \\rightarrow q' : \\{ \\ell_i (S_i) . H_i^T \\} \\}_{i \\in I}) (H^E) =$$\n\n$$B_E^1 (\\{ p \\rightarrow q : \\{ \\ell_i (S_i) . H_i^T \\} \\}_{i \\in I}) (H^E) =$$\n\n$$B_E^1 (\\{ p \\rightarrow q : \\{ \\ell_i (S_i) . H_i^T \\} \\}_{i \\in I}) (H^E) =$$\n\nThe two equations above show how our compatibility (Equation C) comes into play when building back a more general type. E.g., when the projection of $H^T = p \\rightarrow q : \\{ \\ell_i (S_i) . H_i^T \\}_{i \\in I}$ onto $E$ is equal\nto the localisation of a send type \\( H^E = p ! q; \\{ \\ell_i(S_i).H^E_i \\}_{i \\in I} \\) (with \\( p \\in E \\)) then their build-back is \\( p \\rightarrow q; \\{ \\ell_i(S_i).\\mathcal{B}^1_E(H^i) \\times (H^E) \\}_{i \\in I} \\). The case where \\( H^E = p ? q; \\{ \\ell_i(S_i).H^E_i \\}_{i \\in I} \\) is analogous.\n\nThe next example shows how the build-back retains the information both (1) internal to the component of \\( H^E \\) and (2) about the inter-component communication of the system, given by \\( H^i \\).\n\n**Example 4.2 (Build-Back, Intuition).** We are given \\( H^E = s \\rightarrow r : \\ell_1.s|p.l2末端, \\) with internal participants \\( E = \\{ s, r \\} \\), \\( H^i = p \\rightarrow q : s_0, s \\rightarrow p s_2末端, \\) for compatibility, describing inter-component communication in the system: compatibility C holds. Following the equations in Figure 5, we first build back the prefix \\( p \\rightarrow q : s_0 \\), then recursively the prefix \\( s \\rightarrow r : \\ell_1, \\) and ultimately we exploit compatibility and \\( s|p.l2 \\) gets absorbed into \\( s \\rightarrow p : l2末端. \\) Namely, \\( \\mathcal{B}^1_E(H^i) \\times (H^E) = p \\rightarrow q : s_0, s \\rightarrow r : \\ell_1.s \\rightarrow p : l2末端. \\) We observe that \\( \\mathcal{B}^1_E(H^i) \\times (H^E) \\) contains all the interactions, both intra-component (in \\( H^i \\)) and inter-component (in \\( H^E \\)); in other words, \\( \\mathcal{B}^1_E(H^i) \\times (H^E) \\) carries the information both in \\( H^E \\) and in \\( H^i \\). This property of the build-back is formalised by conclusions (1) and (2) of Theorem 4.4.\n\nSome detail from the previous example is hidden in the auxiliary “unmerge” functions unmP and unmL, for projection and localiser respectively. They reproduce in \\( \\mathcal{B}^1_E(H^i) \\times (H^E) \\) a branching structure that is faithful to the branching both in \\( H^i \\) and in \\( H^E \\), where such branching may have been merged when projecting \\( H^i \\) on \\( E = \\{ s, r \\} \\) (with \\( \\sqcap \\), see Definition 3.6) or when localising \\( H^E \\) (with \\( \\sqcup^L \\), see Definition 3.8). We present the unmerge mechanism with the next example, while, for formal details, we refer the interested reader to Appendix B.1.\n\n**Example 4.3 (Unmerge).** We focus on the merge for the localiser \\( \\sqcup^L \\); the case for projection is analogous. We are given \\( H^E = s \\rightarrow r : \\ell_1.s|p.l2末端, l2末端.l2末端, s|p.l2末端末端, \\) and \\( H^i = p \\rightarrow q : s_0, s \\rightarrow p : l2末端, l2末端末端. \\) In this case, \\( H^i \\sqcap E = \\text{loc} \\ H^E = s|p.l2末端, l2末端末端). \\) In particular, when computing loc \\( H^E \\), a merge of branches happens: \\( \\text{loc} \\ H^E = s|p.l2末端末端, l2末端末端.l2末端末端. \\) When building back, we need to unmerge and reproduce the original branching from \\( H^E \\). In particular\n\\[\n s \\rightarrow p : l2末端, l2末端末端 \\} \\sqcup^L (s|p.l2末端末端) \\]\nUnder this hypothesis, unmL returns suitable branches for the build-back:\n\\[\n\\text{unmL} (s \\rightarrow p : l2末端, l2末端末端) \\times (s|p.l2末端末端, s|p.l2末端末端) = [ s \\rightarrow p : l2末端末端末端, s \\rightarrow p : l2末端末端末端 ]\n\\]\nThen, by following the build-back algorithm we obtain:\n\\[\n\\mathcal{B}^1_E(H^i) \\times (H^E) = p \\rightarrow q : s_0, s \\rightarrow r : \\ell_1.s \\rightarrow p : l2末端, l2末端末端.\n\\]\nWe observe that, above, the output of unmL, with arguments \\( H^i \\sqcap E = s \\rightarrow p : l2末端, l2末端末端 \\)\n\\[\n[H^i_1, H^i_2] = [s|p.l2末端末端, s|p.l2末端末端],\n\\]\nis a list of two types \\( [H^i_1, H^i_2] = [s \\rightarrow p : l2末端末端末端, s \\rightarrow p : l2末端末端末端] \\), for which, in particular, the following properties hold: (a) \\( H^i_1 \\sqcap E = H^i_2 \\), for \\( i = 1,2 \\) (b) \\( H^i_1 \\sqcap E \\sqcup^L \\sqcup^L 0 \\), for any \\( E' \\), set of participants such that \\( E \\cap E' = ±0 \\). The nesting of branching for general \\( H^i \\) and \\( H^E \\) may be intricate and tedious; the auxiliary functions unmP and unmL take care of the detail (see Appendix B.1), in a way that properties (a) and (b) as above hold for unmL, and similar ones for unmP (Lemmas B.11 and B.15, Appendix B.1, ). Generally, such properties ensure that both conclusions (1) and (2) (essential for composing multiple subprotocols), of Theorem 4.4, hold.\n\nFinally, we can state our first compositionality result, which certifies the definition of \\( \\mathcal{B} \\).\n\n**Theorem 4.4 (Building Back a Single Component).** We fix a set of participants \\( E \\), and we are given hybrid types \\( H^i \\) and \\( H^E \\), such that: (a) \\( \\text{impart}(H^E) \\subseteq E \\), (b) \\( \\text{epart}(H^E) \\cap E = ±0 \\), and (c) \\( H^i \\sqcap E = \\text{loc} \\ H^E \\), (compatibility C). We set \\( H = \\mathcal{B}^1_E(H^i) \\times (H^E) \\) and we have:\n1. \\( H \\sqcap E = H^E \\) and\n(2) for all $E'$, such that $E' \\cap E = \\emptyset$, $H \\upharpoonright_{E'} = H \\upharpoonright_{E'}$.\n\nMoreover if $\\text{isGlobal}(H^\\uparrow)$ then $\\text{isGlobal}(H)$.\n\nThe proof of Theorem 4.4 proceeds by induction on $\\text{depth}(H^\\uparrow) + \\text{depth}(H^E)$. Its inductive structure follows the defining equations of $B^1$ (Figure 5) and it is non-trivial; the full detail can be found in Appendix B.1 (Theorem B.17), together with the auxiliary lemmas for merging. Theorem 4.4 ensures that the result of building back (backwards, with respect to the usual direction of projection) $H = B^1_E (H^\\uparrow) (H^E)$ contains both (1) the information for the internal communication in $H^E$ (i.e., $H \\upharpoonright_E = H^E$) and (2) the information for the external communication prescribed by $H^\\uparrow$ (i.e., for all $E'$, such that $E' \\cap E = \\emptyset$, $H \\upharpoonright_{E'} = H \\upharpoonright_{E'}$). We describe the algorithm of $B^1$ and the proof outline of Theorem 4.4 below, via example.\n\nExample 4.5 (Definition 4.1 and Theorem 4.4). From Example 3.5, we consider the subprotocol for the strategy department.\n\n$H_{str} = d \\rightarrow ad : prod(nat).d!s:prod(nat).d!f_1 : prod(nat).\\mu X.f_1 ?(ok.d \\rightarrow ad : go.end, wait.d \\rightarrow ad : wait.X)\\}$\n\nThe following protocol, described by the chief designer of the company $D$, coordinates the communication among the three departments (and ignores their internal one).\n\n$G^2 = d \\rightarrow s : prod(nat).d \\rightarrow f_1 : prod(nat).\\mu X.f_1 \\rightarrow d : (ok.f_1 \\rightarrow s : price(nat).end, wait.f_1 \\rightarrow s : wait.X)\\}$\n\nWe observe that $\\text{ipart}(H_{str}) = \\{d, ad\\}$, and that compatibility $C$ holds:\n\n$$\\text{loc } H_{str} = G^\\uparrow \\upharpoonright_{\\{d, ad\\}} = d!s:prod(nat).d!f_1 : prod(nat).\\mu X.f_1 ?d : (ok, end, wait.X)\\}$$\n\nTo obtain $H_1^\\uparrow = B^1_{\\{d, ad\\}} (G^\\uparrow) (H_{str})$, we first build back the internal global prefix in $H_{str}$:\n\n$$H_1^\\uparrow = d \\rightarrow ad : prod(nat).H_1^\\uparrow'$$\n\nWe then proceed by induction, namely $H_1^\\uparrow'$ is built by composing $H^\\uparrow$ and the smaller hybrid type obtained from $H_{str}$, by removing this first prefix: $d!s:prod(nat).d!f_1 : prod(nat)\\ldots$. We observe that the first two send constructs correspond to the projection of the two initial messages of $H^\\uparrow$ (this is guaranteed by the compatibility condition $C$); we take:\n\n$$H_1^\\uparrow'' = d \\rightarrow ad : prod(nat).d \\rightarrow s : prod(nat).d \\rightarrow f_1 : prod(nat).H_1^\\uparrow''$$\n\nTo obtain $H_1^\\uparrow'''$, we observe that the compatibility condition takes care of the recursive construct $\\mu X\\ldots$ and of the first message $f_1 ?d : \\ldots$. After that, in each branch, we need to add first the internal message in $H_{str}$, and then the external messages given by $G^\\uparrow$. We obtain\n\n$$H_1^\\uparrow''' = \\mu X.f_1 \\rightarrow d : (ok.d \\rightarrow ad : go.f_1 \\rightarrow s : price(nat).end, wait.d \\rightarrow ad : wait.f_1 \\rightarrow s : wait.X)\\}$\n\nand, ultimately,\n\n$$H_1^\\uparrow = d \\rightarrow ad : prod(nat).d \\rightarrow s : prod(nat).d \\rightarrow f_1 : prod(nat).\\mu X.f_1 \\rightarrow d : \\begin{cases} ok.d \\rightarrow ad : go.f_1 \\rightarrow s : price(nat).end, \\vspace{1em} \\\\\nwait.d \\rightarrow ad : wait.f_1 \\rightarrow s : wait.X \\end{cases}$$\n\nIndeed, $H_1^\\uparrow$ contains all interactions from both $G^\\uparrow$ and $H_{str}$. The recursive definition of $B^1$ (Definition 4.1) and the inductive proof of Theorem 4.4 follow the procedure presented in this example (Theorem B.17, Appendix B.1).\n\n4.2 Step 2: Multiparty Compositionality\n\n$B^1_E (H^\\uparrow) (H^E)$ composes the subprotocol $H^E$ with the compatibility type $H^\\uparrow$. Here, we iterate this process for an arbitrary number of subprotocols $H_1, \\ldots, H_N$, whenever compatible with respect to $H^\\uparrow$ (Equation $C$): we achieve full multiparty compositionality of subprotocols. The overview is given in Figure 6.\nDefinition 4.6 (Build-Back). Given a list of (disjoint) sets of participants \\( L = [E_1, \\ldots, E_N] \\), we define the partial recursive function \\( \\mathcal{B}_L (H^\\uparrow) ([H_1, \\ldots, H_N]) \\) as follows:\n\n\\[\n\\mathcal{B}_{[E_i]} (H^\\uparrow) ([H_1]) = \\mathcal{B}_{E_i}^1 (H^\\uparrow) (H_1)\n\\]\n\n\\[\n\\mathcal{B}_{[E_i, \\ldots, E_{n+1}]} (H^\\uparrow) ([H_1, \\ldots, H_{n+1}]) = \\mathcal{B}_{[E_i, \\ldots, E_{n+1}]} (\\mathcal{B}_{E_i}^1 H^\\uparrow H_1) ([H_2, \\ldots, H_{n+1}])\n\\]\n\nFrom now on, we leave implicit the first list argument (of sets of participants): we write \\( \\mathcal{B} (H^\\uparrow) ([H_1, \\ldots, H_N]) \\) for \\( \\mathcal{B}_L (H^\\uparrow) ([H_1, \\ldots, H_N]) \\).\n\nTheorem 4.7 (Compositionality for Multiple Protocols). We are given \\( E_1, \\ldots, E_N \\) sets of roles, and the hybrid types \\( H_1, H_2, \\ldots, H_N, \\) and \\( H^\\uparrow \\), such that: (a) \\( E_i \\cap E_j = \\emptyset \\) for all \\( i \\neq j \\), (b) \\( \\text{ipart}(H_i) \\subseteq E_i \\) for all \\( i \\), (c) \\( \\text{epar}(H_i) \\cap E_i = \\emptyset \\) for all \\( i \\), and (d) \\( H^\\uparrow |_{E_i} = \\text{loc} H_i \\) (compatibility C). We set \\( H = \\mathcal{B} (H^\\uparrow) ([H_1, \\ldots, H_N]) \\) and we have that, for all \\( i \\), \\( H |_{E_i} = H_i \\). Moreover if isGlobal\\( (H^\\uparrow) \\) then isGlobal\\( (H) \\).\n\nProof. By induction on \\( N \\). We add to the thesis: \\( (ds_j) \\) for all \\( E' \\), \\( E' \\cap \\bigcup_{i=1,\\ldots,N} E_i = \\emptyset \\), \\( H |_{E'} = H^\\uparrow |_{E'} \\), since we need \\( (ds_j) \\) within the induction hypothesis. The case \\( N = 1 \\) is Theorem 4.4. For \\( N = n + 1 \\), we set \\( H^{n+1} = \\mathcal{B}_{E_i}^1 (H^\\uparrow) (H_1) \\) and we apply the induction hypothesis to \\( H = \\mathcal{B}_{[E_i, \\ldots, E_{n+1}]} (H^{n+1}) ([H_1, \\ldots, H_{n+1}]) \\): we obtain that for \\( i = 2, \\ldots, n \\), \\( H^\\uparrow |_{E_i} = H_i \\). For \\( E_1 \\), since \\( E_1 \\cap \\bigcup_{i=2,\\ldots,n+1} E_i = \\emptyset \\), thanks to \\( (ds_j) \\), we have \\( H |_{E_1} = H^\\uparrow |_{E_1} = H_1 \\) (by Theorem 4.4). For \\( E' \\), \\( E' \\cap \\bigcup_{i=1,\\ldots,n+1} E_i = \\emptyset \\), we have that \\( E' \\cap \\bigcup_{i=2,\\ldots,n+1} E_i = \\emptyset \\), and hence for \\( (ds_j) \\), \\( H |_{E'} = H^\\uparrow |_{E'} \\). We conclude by observing that \\( E' \\cap E_1 = \\emptyset \\) and thus, by Theorem 4.4, \\( H^\\uparrow |_{E'} = H^\\uparrow |_{E'} \\).\n\nExample 4.8 (Theorem 4.7). In Example 4.5, we have seen how to build back \\( G^\\uparrow \\) and \\( H_{\\text{str}} \\) into \\( H^\\uparrow_1 \\), a new hybrid type containing the information both for the inter-protocol communication (from \\( G^\\uparrow \\)) and for the communication inside the strategy department (from \\( H_{\\text{str}} \\)). We observe that compatibility \\( C \\) holds not only for \\( H_{\\text{str}} \\), but also for \\( H_{\\text{sales}} \\) and \\( H_{\\text{fin}} \\), namely:\n\n\\[\n\\text{loc} H_{\\text{sales}} = G^\\uparrow |_{\\{\\text{d,ad}\\}} \\text{d: prod} (\\text{nat}) \\text{d!f}_1: \\text{prod} (\\text{nat}) . \\mu \\text{X}. \\text{f}_1 ? \\text{d}: \\{\\text{ok, wait} \\text{X}\\}\n\\]\n\n\\[\n\\text{loc} H_{\\text{fin}} = G^\\uparrow |_{\\{f, f_2\\}} \\text{d!f}_2: \\text{prod} (\\text{nat}) . \\mu \\text{X}. \\text{f}_1 ! \\text{d}: \\{\\text{ok, s, price} (\\text{nat}). \\text{end, wait} \\text{X}\\}\n\\]\n\nThe hypothesis of Theorem 4.7 holds and thus we can build \\( G = \\mathcal{B} (G^\\uparrow) ([H_{\\text{str}}, H_{\\text{sales}}, H_{\\text{fin}}]) \\), such that \\( G |_{\\{\\text{d,ad}\\}} = H_{\\text{str}}, G |_{\\{s,w\\}} = H_{\\text{sales}}, \\) and \\( G |_{\\{f, f_2\\}} = H_{\\text{fin}} \\). To make the construction of \\( G \\) explicit, we follow the inductive proof structure of Theorem 4.7. The base case is taken care of in Example 4.5, where we apply Theorem 4.4 and build \\( H^\\uparrow_1 \\), by composition of \\( G^\\uparrow \\) and \\( H_{\\text{str}} \\), we obtain:\n\n\\[\nH^\\uparrow_1 = \\text{d} \\rightarrow \\text{ad} : \\text{prod} (\\text{nat}) . \\text{d} \\rightarrow s : \\text{prod} (\\text{nat}) . \\text{d} \\rightarrow \\text{f}_1 : \\text{prod} (\\text{nat}) . \\mu \\text{X}. \\text{f}_1 \\rightarrow \\text{d} : \\{\\text{ok, d} \\rightarrow \\text{go} : \\text{f}_1 \\rightarrow s : \\text{price} (\\text{nat}). \\text{end, wait} \\text{d} \\rightarrow \\text{ad} : \\text{wait} : \\text{f}_1 \\rightarrow s : \\text{wait} \\text{X}\\}\n\\]\n\nWe observe that \\( H^\\uparrow_1 |_{\\{s, w\\}} = G^\\uparrow |_{\\{s, w\\}} \\), hence, since \\( C \\) still holds, we can apply again the build-back procedure and obtain:\n\n4.3 Step 3: Compositionality through Projection\n\nWith Definition 3.6, we have generalised the MPST projection to hybrid types. We prove that\ngeneralised projection well-behaves with respect to set inclusion.\n\n**Theorem 4.9 (Projection Composes over Set Inclusion).** Given $H$, $E_1$ and $E_2$, $E_2 \\subseteq E_1$, if\n$H \\downarrow_{E_1}$ is defined, then $(H \\downarrow_{E_1}) \\downarrow_{E_2} = H \\downarrow_{E_2}$.\n\n**Proof.** By structural induction on $H$ (see Appendix B.2). \\hfill \\Box\n\n**Theorem 4.9** is the last fundamental ingredient to achieve \ndistributed protocol specification.\n\n**Corollary 4.10 (Distributed Protocol Specification).** Given $E_1, \\ldots , E_N$ disjoint sets of par-\nticipants, a global type $G^\\dagger$, and $H_1, \\ldots , H_N$ hybrid types, such that: (a) $\\text{epart}(H_i) = E_i$ for all $i$,\n(b) $\\text{ipart}(H_i) \\cap E_i = \\emptyset$ for all $i$, (c) $\\text{ipart}(G^\\dagger) \\subseteq \\bigcup_{i=1,\\ldots ,N} E_i$, and\nd) $G^\\dagger \\downarrow_{E_i} = \\text{loc} H_i$ (compatibility $C$); there exists $G$ such that, for all $i$, for all $r \\in E_i, G \\downarrow_{\\{r\\}} = H_i \\downarrow_{\\{r\\}}$.\n\n**Proof.** We set $G = \\mathcal{B}(G^\\dagger) ([\\{H_1, \\ldots , H_N\\}]);$ by Theorem 4.7, $G$ is global and such that $G \\downarrow_{E_i} = H_i$.\nThen, we apply Theorem 4.9 and we obtain, for $r \\in E_i, G \\downarrow_{\\{r\\}} = G \\downarrow_{E_i} \\downarrow_{\\{r\\}} = H_i \\downarrow_{\\{r\\}}$. We observe that $G \\downarrow_{\\{r\\}}$ is a local type, for all $r$, (Remark 3.7).\n\n**Example 4.11.** In Examples 4.5 and 4.8, the protocol designer for each department has given their\nhybrid type, $H_{\\text{str}}$, $H_{\\text{sales}}$, and $H_{\\text{fin}}$, disciplining internal communication (with messages $p \\rightarrow q$ and\nspecifying the communication with other departments (with sends/receives, $p/q/p?q$). Compatibility\n(Equation $C$) has been verified against $G^\\dagger$, as described by the chief designer $D$. In (Example 4.8)\nwe build back $G$ (we observe that is $\\text{isGlobal}(G^\\dagger)$ implies $\\text{isGlobal}(G)$). Corollary 4.10 holds and\nprojections of components $H_{\\text{str}}$, $H_{\\text{sales}}$, and $H_{\\text{fin}}$ onto single participants are local types, also\nprojections of $G$ (Theorem 4.9), the global type disciplining the whole system. For instance, if we wanted\nto get the local type for $d$, traditionally, we would do so by projecting $G$. With our distributed\nprotocol specification, it is enough to project $H_{\\text{str}}$ onto $d$.\n\n\\[\nG \\downarrow_{\\{d\\}} = (G \\downarrow_{\\{ad\\}})\\downarrow_{\\{d\\}} = H_{\\text{str}} \\downarrow_{\\{d\\}} = \\\\\n\\text{d!ad:prod(nat).d!s:prod(nat).d!f1:prod(nat).}\\mu X.f1?d{ok.d!ad;go.end, wait.d!ad;wait.X}\n\\]\n\nIf instead want to implement processes for $f_1$ and $f_2$, we can obtain the local types from $H_{\\text{fin}}$.\n\n\\[\nG \\downarrow_{\\{f1\\}} = H_{\\text{fin}} \\downarrow_{\\{f1\\}} = d?f1:prod(nat).f1?f2:prod(nat).\\mu X.f2?f1\\{price(nat).end, wait.f1?d;wait.f1?s;wait.X\n\\]\n\n\\[\nG \\downarrow_{\\{f2\\}} = H_{\\text{fin}} \\downarrow_{\\{f2\\}} = f1?f2:prod(nat).\\mu X.f2?f1\\{price(nat).end, wait.X\n\\]\n\nWe can proceed analogously for all participants.\nRemark 4.12 (Applicability and Preservation of Semantics). Example 4.11 displays the essence of our theory, formally captured by Corollary 4.10: for a system specified in a distributed way, with components $H_1, \\ldots, H_N$ and compatibility type $G^\\dagger$, there is no need for an explicit description of $G$. After compatibility checks (Equation C), our theory builds back a well-formed global type $G$ for the whole system, and the session of local types, projections of $G$, can be obtained, in a distributed fashion, by directly projecting subprotocols, since, for $p \\in \\text{ipart}(H_i)$, $H_i \\upharpoonright \\{p\\} = G \\upharpoonright \\{p\\}$.\n\nAt the design stage, each designer $D_i$ gives the subprotocol $H_i$ and, with the simple equality check C, they make sure that their protocol is compatible with $G^\\dagger$ (described by the chief designer $D$). At the type-checking/implementation stage, the designer $D_i$ independently obtains local types for well-behaved implementations directly from their specification $H_i$. $D_i$ is never concerned with the communication happening internally to, or among, other components. What guarantees global well-behaviour is the existence of $G$, proved once and for all by our theory; no designer or programmer needs its explicit description. We have achieved distributed protocol specification.\n\nDesirable MPST semantic guarantees, such as liveness and deadlock freedom, are preserved by our theory, thanks to its semantics preservation. Our compositionality-through-projection technique can explicitly build back a protocol as a global type that is traditionally well-formed (see, e.g., [Deniélou and Yoshida 2013; Honda et al. 2016]). Thus, our theory brings modularity to the protocol design phase, but, after such distributed specification, the result is a traditional MPST system, with a single global type that projects on local types for all participants, which benefits from existing semantics results from the MPST literature.\n\nRemark 4.13 (On Hybrid Types). Central to this work is Definition 3.3 of hybrid types. Our theory shows how “open” subprotocols, interacting with other components of the system, can be specified as hybrid types, safely composed into a global type, and projected onto local types.\n\nThe syntax of hybrid types is simply the combination of the syntaxes of global and local types and, through the predicates isGlobal($H$) and isLocal($H$), we can isolate global and local types respectively, from the rest of hybrid types. This choice makes our development compatible with existing MPST systems and is key to semantics preservation: in our compositionality theory, well-formed global types guarantee semantics properties and local types are used for participant implementation, exactly as in traditional MPST (see Corollary 4.10 and Remark 4.12).\n\nAt the same time, dealing with a single syntax (hybrid types) simplifies our theory significantly. This paper proposes an approach to protocol compositionality that heavily relies on projection. Traditional MPST projection operates on global types and returns local types for implementation. Our generalised projection, instead, takes a hybrid type and returns a hybrid type, but, since global and local types are hybrid types, our projection maintains and extends the functionalities of the traditional operator. The main gain is flexibility: a function with the same domain as its codomain can be composed with itself and this is central in our proofs (see Theorem 4.9 and its role in the proof of Corollary 4.10). In other words, instead of working with multiple operators (which would have very similar definitions) and proving them compatible, we rely on a single one: generalised projection. In particular, we apply projection in the following key steps of our development:\n\n- projecting the component $H^E_p$ of a system onto one of its internal participants $p$, gives—as it is customary in the literature—the local type $L_p$ for implementing $p$;\n- projecting the type $G^\\dagger$ is necessary for compatibility $C: G^\\dagger \\upharpoonright E = \\text{loc } H^E$; and\n- the preservation of projection (Theorem 4.9) ensures applicability and correctness: local types for implementation, obtained by separately projecting the distributed components, are also projections of a single, well-formed global type for the whole system (equation $G \\upharpoonright \\{p\\} = H \\upharpoonright \\{p\\}$, Corollary 4.10).\n5 CASE STUDIES\n\nIn this section, we evaluate our development with case studies. In §5.1, we discuss the role of the parallel construct \\( H_1|H_2 \\) in our protocol composition. Then, we consider the industry-standard protocol for authorisation, OAuth 2.0, [Hardt 2012; Horne 2020]: in §5.2, we observe the modularity benefits of our theory, and, in §5.3, we reach an optimisation for it. In §5.4, we show how hybrid types can be smoothly extended to feature delegation and explicit connections.\n\n5.1 On the Parallel Construct and Compositionality\n\nOur work enriches the type system of MPST with compositionality at the protocol-description level, while retaining the traditional syntax of local types. Consequently, the targeted process language is standard [Castro-Perez et al. 2021; Glabbeek et al. 2021]. In particular, local types and processes are single-threaded. On the other hand, to allow the description of protocols where two different components execute independently, without exchanging messages with each other, we have added the parallel construct to the syntax of hybrid (and global) types.\n\nThe parallel construct (or parallel composition) for global types appears in the first presentation of MPST [Honda et al. 2008], but dismissed in subsequent literature [Bettini et al. 2008; Castro-Perez et al. 2021; Coppo et al. 2015]. For achieving compositionality, without requiring further well-formedness restrictions on global types, we need to explicitly add parallel composition \\( H_1|H_2 \\). Let us consider the following distributed specification:\n\n\\[\nG^p_{\\parallel} = p \\to r : t . \\text{end} \\quad H^1_{\\parallel} = \\text{p}|r ; t . \\mu X . p \\to q : \\{\\ell_1, X, \\ell_2, \\text{end}\\} \\quad H^2_{\\parallel} = \\text{p}|r ; t . \\mu Y . r \\to s : \\{\\ell_3, Y, \\ell_4, \\text{end}\\}\n\\]\n\nCompatibility holds: \\( G^p_{\\parallel} \\models_{\\{p,q\\}} \\text{p}|r ; t . \\text{end} = \\text{loc } H^1_{\\parallel} \\), and \\( G^p_{\\parallel} \\models_{\\{r,s\\}} \\text{p}|r ; t . \\text{end} = \\text{loc } H^2_{\\parallel} \\). Our theory guarantees the existence of a well-formed global type for the whole system, which entails a deadlock-free session: \\( G^p_{\\parallel} = p \\to r : t . (\\mu X . p \\to q : \\{\\ell_1, X, \\ell_2, \\text{end}\\}) \\mid (\\mu Y . r \\to s : \\{\\ell_3, Y, \\ell_4, \\text{end}\\}) \\). Without parallel composition, it is not clear how to compose \\( H^1_{\\parallel} \\) and \\( H^2_{\\parallel} \\), even if they are compatible with respect to \\( G^p_{\\parallel} \\). Indeed, recent work [Glabbeek et al. 2021] has drawn attention to the role of the parallel construct in traditional MPST: by exploiting a similar example to the \\( G^p_{\\parallel} \\) above, the authors show that, if the syntax does not include parallel composition, there are non-deadlocked sessions that do not have a global type.\n\n5.2 Distributed Specification for OAuth 2.0\n\nWe consider the industry-standard protocol for authorisation, OAuth 2.0, [Hardt 2012; Horne 2020]. In such protocol, the owner of a resource gives approval (through the OAuth server) for an external application to access some resource; the OAuth server ensures, by means of tokens, that the sensitive data of the owner are not shared with the external application.\n\nWe present a specification for the OAuth 2.0 protocol in two components (Figure 7): a first designer \\( D_{\\text{auth}} \\) gives the hybrid type \\( H_{\\text{auth}} \\) for the OAuth server \\( \\text{oa} \\) and the resource owner \\( \\text{ow} \\), while a second \\( D_{\\text{res}} \\), is in charge of the interactions involving an untrusted app \\( \\text{ua} \\) and the resource service \\( \\text{res} \\), \\( H_{\\text{res}} \\). Separately, a chief designer describes the compatibility type \\( G^p_{\\text{oa}} \\). Compatibility holds, \\( G^p_{\\text{oa}} \\models_{\\{\\text{oa},\\text{ow}\\}} \\text{loc } H_{\\text{auth}} \\) and \\( G^p_{\\text{oa}} \\models_{\\{\\text{ua},\\text{res}\\}} \\text{loc } H_{\\text{res}} \\), and Corollary 4.10 guarantees the existence of a well-formed global type for the whole protocol.\n\nLet us focus on the component \\( H_{\\text{res}} \\), and in particular on its subcomponent \\( H_{\\text{res,acc}} \\), which contains exclusively internal interactions: once authorisation is granted, the untrusted app communicates directly with the resource service. We observe then that \\( H_{\\text{res,acc}} \\) can be specified modularly:\n\n\\[\\text{For more details on the role of parallel composition in the inductive proof of Theorem 4.4, see the full proof in Appendix B.1, Theorem B.17}\\]\nthe designer $D_{\\text{res}}$ could, at a later stage, specify a different protocol, $H'_{\\text{res acc}}$, for the interaction between $\\text{ua}$ and $\\text{res}$, without affecting compatibility. We recognise one extra benefit of our theory in modular specification for intra-component communication: a designer ($D_{\\text{res}}$) can modify the specification of their protocol ($H_{\\text{res}}$) over time, in its internal interactions ($H_{\\text{res acc}}, H'_{\\text{res acc}}$), as long as its external communication (loc $H_{\\text{res}}$)– and hence compatibility with respect to the prescription of the chief designer ($G^\\dagger_{\\text{oa}}$)—is preserved.\n\n5.3 Optimisation of OAuth 2.0 Specification\n\nBy inspecting the types in Figure 7, we notice that all inter-component interactions (between $H_{\\text{auth}}$ and $H_{\\text{res}}$) go through the participant $\\text{oa}$ and, hence, they are all documented by $G^\\dagger_{\\text{oa}}$, but also in $H_{\\text{auth}}$. Here, describing explicitly $G^\\dagger_{\\text{oa}}$ looks redundant and we ask ourselves whether a more efficient specification is possible. It turns out that we can omit the specification of $G^\\dagger_{\\text{oa}}$ for the OAuth 2.0 protocol and optimise distributed specification (Corollary 4.10) in general.\n\n**Corollary 5.1 (Distributed MPST Specification, Optimisation).** Given $E, E_1, \\ldots, E_N$ disjoint sets of participants, a global type $G^\\dagger$, and $H_1, \\ldots, H_N$ hybrid types, such that: (a) $\\text{ipart}(H_i) = E_i$, for all $i = 1, \\ldots, N$, (b) $\\text{ipart}(H_i) \\cap E_i = \\emptyset$, for all $i$, (c) $\\text{ipart}(G^\\dagger) \\subseteq \\left( \\bigcup_{i=1,\\ldots,N} E_i \\right) \\cup E$, and (d) $G^\\dagger |_{E_i} = \\text{loc} H_i$; there exists $G$ such that, for all $i = 1, \\ldots, N$, for all $r \\in E_i$, $G^\\dagger r = H_i \\upharpoonright r$, and for all $r \\in E, G^\\dagger r = G^\\dagger \\upharpoonright r$.\n\nThe proof of the above corollary is analogous to the proof of Corollary 4.10 and entails the same semantic guarantees, since it leads to the existence of a global type for the whole system. However, in Corollary 5.1, $G^\\dagger$ plays a twofold role: (a) it is the hybrid type, communication subprotocol for...\nthe component with set of participants \\( E \\), and (b) it is the compatibility protocol, carrying all the inter-component interactions of the system. For OAuth 2.0, by exploiting Corollary 5.1, we obtain a more efficient distributed specification (Figure 8). Only two hybrid types, one for each component, are specified, provided that one contains also the compatibility information. We observe, with notations from Figures 7 and 8 that \\( H_{\\text{auth}} \\vdash_{\\{p\\}} = G_{\\text{op}} \\vdash_{\\{p\\}}, \\) for \\( p \\in \\{\\text{oa,ow}\\} \\). Hence, for all participants, in both specifications we obtain the same local types for implementation. However, in the optimised case of Figure 8, for compatibility, we only need to check one equality: \\( G_{\\text{op}} \\vdash_{\\{\\text{oa,ow}\\}} = \\text{loc} \\ H_{\\text{res}}. \\)\n\nRemark 5.2 (Local Types from Partial Protocols). We observe that Corollaries 4.10 and 5.1 prescribe differently how to obtain local types for implementation. In Corollary 4.10, we project each \\( H_i \\) onto its internal participants (in \\( E_i \\)) to get the right local types. \\( G^\\dagger \\) has the sole role of disciplining inter-component communication for compatibility, hence all its projections onto single participants (even if well-defined) are not meant for implementation. In Corollary 5.1, instead, the global type \\( G^\\dagger \\) not only provides for compatibility, but also describes the internal communication of the component that is concerned with the participants in \\( E \\). Thus, if \\( r \\in E_i \\), the respective local type is obtained by \\( H_i \\vdash_{\\{r\\}} \\), while, if \\( r \\in E \\), the local type for implementing \\( r \\) is \\( G^\\dagger \\vdash_{\\{r\\}} \\).\n\n5.4 An Extension to Delegation and Explicit Connections\nThe MPST literature offers a variety of formalisms that enrich the type system with expressive features [Bocchi et al. 2014; Castro-Perez and Yoshida 2020; Lagaillardie et al. 2022; Viering et al. 2021; Zhou et al. 2020], while maintaining the central mechanism of projecting global types onto local types for distributed implementation. This suggests that our compositional methodology is general enough to capture more sophisticated formalisms than core MPST. In this section, we support this intuition with a case study: we extend hybrid types to include delegation and explicit connections. At the end of the section (Example 5.7), we show that this suitability for extensions is a prerogative of our compositionality-through-projection, differently from other compositionality approaches based on input/output matching [Barbanera et al. 2021; Stolze et al. 2021].\n\nBoth delegation and explicit connections are relevant and practical features, which have been extensively studied by the literature on concurrency. Delegation—the mechanism in which a participant appoints a different participant to act on their behalf—first appears in the context of object-oriented concurrency [Agha 1990; Ungar and Smith 1987; Yonezawa and Tokoro 1986] and, naturally, it has been implemented in mainstream object-oriented languages [Hu et al. 2008; Imai et al. 2020; Scalas and Yoshida 2016]. Over the years, the session-type literature has investigated the verification of concurrency in the presence of delegation [Bettini et al. 2008; Honda et al. 1998, 2008; Scalas et al. 2017]. In particular, we take the approach of Castellani et al. [2020], who treat delegation as internal to the session, in contrast with channel-passing delegation, which requires the interleaving of sessions. Thus, the authors can model (internal) delegation simply by adding specific constructs to the syntax of global types. Moreover, global types from this paper benefit from the flexibility of explicit connections: some participant may or may not take part in the communication, depending on the choice made by some other participant at a previous stage of execution. Explicit connections are common in the design of real-world protocols [Hardt 2012; MIT 2022] and have been significantly addressed by the literature [Castellani et al. 2019; Gheri et al. 2022; Harvey et al. 2021; Hu and Yoshida 2017]. Specifically, our approach is immediately compatible with the type system and the semantics in [Castellani et al. 2020] (from which we take most notation): we can compose subprotocols into a well-formed and well-delegated global type, projecting on local session types for the whole communicating system. Thus, no new semantics is needed, but MPST semantics guarantees (subject reduction, session fidelity, and progress) hold.\nFor this case study, we focus on our novel notion of compatibility through projection (Equation C). Developing the full theory goes beyond the scope of this paper: the structure of the proofs would be exactly the same as in our core theory (Section 4). Instead, we (a) extend hybrid types to delegation and explicit connections, (b) generalise projection, (c) define the localiser, and (d) state compatibility.\n\nDefinition 5.3 (Hybrid Types with Delegation). We define a set of prefixes for global and local messages; when \\( p \\) establishes an explicit connection to \\( q \\), we use the superscript \\( \\epsilon \\).\n\n\\[\n\\alpha := p \\rightarrow q \\mid p \\rightarrow^\\epsilon q \\quad \\pi^\\text{out} := p!q \\mid p\\epsilon q \\quad \\pi^\\text{in} := p?q \\mid p\\epsilon q \\quad \\sigma := \\alpha \\mid \\pi^\\text{out}\n\\]\n\nHybrid types with delegation are defined inductively by:\n\n\\[\nH := \\text{end} \\mid X \\mid \\mu X.H \\mid H_1\\mid H_2 \\mid \\bigwedge_{i\\in I} \\alpha_i^\\text{out}(\\ell_i); H_i \\mid \\bigwedge_{i\\in I} \\pi_i^\\text{in}(\\ell_i); H_i \\mid \\bigvee_{i\\in I} \\pi_i^\\text{out}(\\ell_i); H_i \\mid p\\langle \\bullet; q; H \\mid q\\bullet \\rangle \\circ p; H \\mid p\\langle \\bullet; q; H \\mid q\\bullet \\rangle \\circ [p]; H\n\\]\n\nWithout loss of generality, we omit payload types (sorts) from the syntax above: formally, participants only exchange labels \\( \\ell \\). For degenerate branchings (with a single branch, where no actual choice happens) we omit the operators \\( \\bigwedge \\) and \\( \\bigvee \\) and we simply write the message (starting with a prefix \\( \\alpha \\), \\( \\pi^\\text{out} \\), \\( \\pi^\\text{in} \\)).\n\nHybrid types with delegation (Definition 5.3) endow with local send/receive constructs the global types from [Castellani et al. 2020]. In particular, global choices and union types from [Castellani et al. 2020] are particular cases of the above syntax. The global choice, \\( \\bigwedge_{i\\in I} \\alpha_i^\\text{out}(\\ell_i); H_i \\), is obtained by asking that, in \\( \\bigwedge_{i\\in I} \\alpha_i^\\text{out}(\\ell_i); H_i \\), all \\( \\alpha_i^\\text{out} \\) are global messages, \\( \\alpha_i^\\text{out} \\). Local union (send) types, \\( \\bigvee_{i\\in I} \\pi_i^\\text{out}(\\ell_i); H_i \\), are now written as \\( \\bigwedge_{i\\in I} \\pi_i^\\text{out}(\\ell_i); H_i \\), where all \\( \\pi_i^\\text{out} \\) are send constructs \\( \\pi_i^\\text{out} \\). In what follows we discuss how Definition 5.3 is a direct extension of Definition 3.3.\n\nWe observe that branching is more permissive than in Definition 3.3.\n\n- In a single choice \\( \\bigwedge_{i\\in I} \\pi_i^\\text{out}(\\ell_i); H_i \\) the sender \\( p \\) is unique, but receivers may be different, internal or external: in choices we allow the mixing of global messages \\( \\alpha \\) and send constructs \\( \\pi^\\text{out} \\).\n- Intersection types \\( \\bigwedge_{i\\in I} \\pi_i^\\text{in}(\\ell_i); H_i \\) combine receive constructs \\( \\pi^\\text{in} \\), possibly with different senders (and receivers).\n\nRemark 5.4 (Generalising Hybrid Types to Delegation). The syntax of hybrid types with delegation (Definition 5.3) is a generalisation of the core syntax of hybrid types (Definition 3.3). For each construct in Definition 3.3, we show how it can be expressed in the formalism of 5.3.\n\n- end, \\( X, \\mu X.H \\), and \\( H_1\\mid H_2 \\) are preserved.\n- \\( p!q; \\{\\ell_i; H_i\\}_{i\\in I} \\) can be written as \\( \\bigwedge_{i\\in I} \\alpha_i^\\text{out}(\\ell_i); H_i \\), with \\( \\alpha_i^\\text{out} = p!q \\) for all \\( i \\in I \\).\n- \\( p?q; \\{\\ell_i; H_i\\}_{i\\in I} \\) can be written as \\( \\bigwedge_{i\\in I} \\pi_i^\\text{in}(\\ell_i); H_i \\), with \\( \\pi_i^\\text{in} = p?q \\) for all \\( i \\in I \\).\n- \\( p \\rightarrow q; \\{\\ell_i; H_i\\}_{i\\in I} \\) can be written as \\( \\bigwedge_{i\\in I} \\pi_i^\\text{out}(\\ell_i); H_i \\), with \\( \\pi_i^\\text{out} = p \\rightarrow q \\) for all \\( i \\in I \\).\n\nThe global construct \\( p\\langle \\bullet; q; H \\mid q\\bullet \\rangle \\circ p; H \\) models a forward delegation where \\( p \\) delegates their behaviour to \\( q \\); then, such behaviour is given back with the global construct for backward delegation, \\( q\\bullet \\circ \\bullet; p; H \\). The notation for local constructs is analogous: active forward delegation \\( p\\langle \\bullet; q; H \\mid q\\bullet \\rangle \\circ [p]; H \\), passive backward delegation \\( [q\\bullet] \\circ \\bullet; p; H \\), passive forward delegation \\( [p] \\circ \\bullet; q; H \\), and active backward delegation \\( q\\bullet \\circ [p]; H \\). As in our core theory (see Definition 3.3), local constructs carry both internal participants and external ones (in square brackets): e.g., in \\( p\\langle \\bullet; q; H \\mid q\\bullet \\rangle \\circ [p]; H \\), \\( p \\) (internal) delegates their behaviour to the participant \\( q \\) of a different component (external).\n\nIn order to make the notation lighter, we ignore sorts in both syntaxes: only labels \\( \\ell \\) are sent.\nExample 5.5 (Global Types with Delegation and Explicit Connections). Here, we consider two simple examples that display in isolation the features of delegation and explicit connections. Let us consider the following global protocols, written with the syntax of hybrid types with delegation (Definition 5.3).\n\n\\[\nG_d = \\text{customer } \\rightarrow \\text{seller(}ok\\text{);}\\text{seller} \\circ \\langle \\bullet \\text{bank}; \\text{customer } \\rightarrow \\text{seller(}card\\text{)}; \\text{bank}\\bullet \\rangle \\circ \\text{seller}; \\text{end}\n\\]\n\nIn \\(G_d\\), after the \\text{customer} has given the \\text{ok}, the \\text{seller} delegates to the \\text{bank} their role in the communication \\(\\langle \\bullet \\text{bank}\\rangle\\). Namely, when the \\text{customer} sends their \\text{card} number to the \\text{seller}, they are in fact sharing that information with the \\text{bank}. With the construct \\(\\text{bank}\\bullet \\circ \\text{seller}\\), the \\text{bank} delegates back their role to the \\text{seller}.\n\n\\[\nG_{ec} = \\text{user } \\rightarrow \\text{website(}location\\text{);} \\begin{array}{l}\n\\text{website } \\rightarrow \\epsilon \\text{EUshop(}open\\text{);}\\text{EUshop } \\rightarrow \\text{user(}EUfrontpage\\text{);}\\text{end}\n\\end{array}\n\\begin{array}{l}\n\\text{website } \\rightarrow \\epsilon \\text{UKshop(}open\\text{);}\\text{UKshop } \\rightarrow \\text{user(}UKfrontpage\\text{);}\\text{end}\n\\end{array}\n\\]\n\nIn \\(G_{ec}\\), after the \\text{website} receives the \\text{user}’s location, it decides whether to (explicitly) connect them to the \\text{EUshop} or to the \\text{UKshop}. Then the \\text{EUshop} (resp. the \\text{UKshop}) sends the \\text{EUfrontpage} (resp. the \\text{UKfrontpage}) to the \\text{user}. Here in the first branch (resp. the second) of the choice, there is an explicit connection \\text{website } \\rightarrow \\epsilon \\text{EUshop} (resp. \\text{website } \\rightarrow \\epsilon \\text{UKshop}) to the participant \\text{EUshop} (resp. \\text{UKshop}), which does not appear in the other branch.\n\nWe adopt the definition of well-delegated type from [Castellani et al. 2020] (Definition 4.11); in particular a forward delegation (e.g., \\(\\text{p} \\circ \\langle \\bullet q \\rangle\\)) is always followed by a corresponding backwards one (e.g., \\(\\bullet q \\circ q\\)); also, choices must not appear between corresponding forward and backward delegation.\n\nWe define \\textit{projection} and \\textit{localiser} for hybrid types with delegation, by extending Definitions 3.6 and 3.8, §3.2. The main differences are listed below.\n\n- Projection behaves on delegation constructs following the same intuition as for messages. E.g., \\((\\text{p} \\circ \\langle \\bullet q; \\text{H} \\rangle) \\uparrow_E = \\text{p} \\circ \\langle \\bullet q; (\\text{H} \\uparrow_E) \\rangle\\) if \\(\\{\\text{p}, \\text{q}\\} \\subseteq E\\), or \\((\\text{p} \\circ \\langle \\bullet q; \\text{H} \\rangle) \\uparrow_E = \\text{p} \\circ \\langle \\bullet q; (\\text{H} \\uparrow_E) \\rangle\\) if \\(\\{\\text{p}, \\text{q}\\} \\not\\subseteq E\\), where projection needs to keep track of \\(\\text{p}\\) delegating to \\(\\text{q}\\), as indicated by the notation \\(\\uparrow_E \\uparrow_{\\{\\text{p}, \\text{q}\\}}\\).\n- Branches with explicit connections of a participant \\(s\\) can be merged with branches where \\(s\\) does not appear; e.g., if \\(\\text{H} \\uparrow_{\\{s\\}} = \\{\\{\\text{p} \\circ \\langle \\bullet q; \\text{H} \\rangle, \\text{end} \\text{p} \\rightarrow \\epsilon \\text{ s(} \\text{H} \\text{)}; \\text{s } \\rightarrow \\epsilon \\text{ } \\text{H(} \\text{p} \\text{)}; \\text{end}\\}\\), then \\(\\text{H} \\uparrow_{\\{s\\}} = \\{\\{\\text{p} \\circ \\langle \\bullet q; \\text{H} \\rangle, \\text{end} \\text{p} \\rightarrow \\epsilon \\text{ s(} \\text{H} \\text{)}; \\text{s } \\rightarrow \\epsilon \\text{ } \\text{H(} \\text{p} \\text{)}; \\text{end}\\}\\).\n- We allow merging of receive constructs with different senders; e.g., with \\(\\text{H}\\) as in the bullet point above, \\(\\text{H} \\uparrow_{\\{s\\}} = \\{\\{\\text{p} \\circ \\langle \\bullet q; \\text{H} \\rangle, \\text{end} \\text{p} \\rightarrow \\epsilon \\text{ s(} \\text{H} \\text{)}; \\text{s } \\rightarrow \\epsilon \\text{ } \\text{H(} \\text{p} \\text{)}; \\text{end}\\}\\).\n- As in our core theory §3.2, the localiser skips global constructs and retains local ones; e.g., \\(\\text{loc p} \\circ \\langle \\bullet q; \\text{H} \\rangle = \\text{loc H}\\) and \\(\\text{loc p} \\circ \\langle \\bullet q; \\text{H} \\rangle = \\text{loc p} \\circ \\langle \\bullet q; \\text{H} \\rangle\\).\n\nThe partial function \\(\\_d\\) généralises the delegation projection functions \\(\\_d_1\\) and \\(\\_d_2\\) from [Castellani et al. 2020] (Figure 6); this function is of a sequential nature: it is not defined for branching, recursion, and parallel constructs. Full definitions of projection \\(\\_d\\), the auxiliary delegation projection \\(\\_d\\), and localiser \\(\\text{loc}\\) are in Appendix B.3 and compatible with [Castellani et al. 2020].\n\nExample 5.6 (Projection with Delegation and Explicit Connections). Let us consider \\(G_d\\) and \\(G_{ec}\\) from Example 5.5 and, in particular, their projections onto single participants.\n\nThe intuition behind the delegation constructs in \\(G_d\\) is well displayed by its projections.\n\n\\[\n\\begin{align*}\nG_d \\uparrow_{\\{\\text{seller}\\}} &= \\text{seller(}!\\text{customer(}ok\\text{);}\\text{seller} \\circ \\langle \\bullet \\text{bank}; \\text{bank}\\bullet \\rangle \\circ \\text{seller}; \\text{end} \\\\\nG_d \\uparrow_{\\{\\text{customer}\\}} &= \\text{seller(}!\\text{customer(}ok\\text{);}\\text{customer!seller(}card\\text{)}; \\text{end} \\\\\nG_d \\uparrow_{\\{\\text{bank}\\}} &= \\text{seller} \\circ \\langle \\bullet \\text{bank}; \\text{bank}\\bullet \\rangle \\circ \\text{seller}; \\text{end}\n\\end{align*}\n\\]\nAfter actively delegating their role to the bank ($\\text{seller} \\bowtie \\langle \\bullet \\text{bank} \\rangle$) and before passively being delegated their role back ($\\langle \\text{bank} \\bullet \\rangle \\bowtie \\text{seller}$), the seller is not involved in any communication ($G_d \\mid \\text{seller}$). At the same time, the bank plays the opposite role: is passive in receiving the delegation from seller ($\\langle \\text{seller} \\bowtie \\langle \\bullet \\text{bank} \\rangle \\rangle$) and active in delegating the role back ($\\langle \\text{bank} \\bullet \\rangle \\bowtie \\text{seller}$). Furthermore, we observe that, while the bank knows that they are receiving the card number from the customer, the customer acts as if they are sending it directly to the seller: as expected, the customer is not involved in the delegation process and hence ignores it.\n\nWhen projecting $G_{ec}$ onto its participants, we obtain the following types.\n\n$$G_{ec} \\mid \\text{(user)} = \\text{user}!\\text{website} (\\text{location}); \\mid \\begin{align*} \\text{EUser}\\text{?user} (\\text{EUfrontpage}) &; \\text{end} \\\\ \\text{UKUser}\\text{?user} (\\text{UKfrontpage}) &; \\text{end} \\end{align*} \\mid \\begin{align*} \\text{website}\\text{!EUser} (\\text{open}) &; \\text{end} \\\\ \\text{website}\\text{!UKUser} (\\text{open}) &; \\text{end} \\end{align*}$$\n\n$$G_{ec} \\mid \\text{(website)} = \\text{user}?\\text{website} (\\text{location}); \\mid \\begin{align*} \\text{website}\\text{!EUser} (\\text{open}) &; \\text{end} \\\\ \\text{website}\\text{!UKUser} (\\text{open}) &; \\text{end} \\end{align*}$$\n\n$$G_{ec} \\mid \\text{(EUser)} = \\text{website}\\text{?EUser} (\\text{open}); \\text{EUser}\\text{?user} (\\text{EUfrontpage}) \\mid \\text{end}$$\n\n$$G_{ec} \\mid \\text{(UKshop)} = \\text{website}\\text{?UKshop} (\\text{open}); \\text{UKUser}\\text{?user} (\\text{UKfrontpage}) \\mid \\text{end}$$\n\nWe observe that the participants EUser and UKUser are concerned only with the interactions that happen after their explicit connection (website?EUser and website?UKUser respectively) and not with the communication in the other branch, where they are not connected.\n\nWe now define compatibility. In the usual multi-component scenario, we give hybrid types (with delegation and explicit connections) $H_1, H_2, \\ldots, H_N$, for each component, and a compatibility type $G^\\dagger$. As in §4, we consider the generic $H^E \\in \\{H_1, H_2, \\ldots, H_N\\}$ (with $E$ being the set of its internal participants) in isolation and we state compatibility:\n\n$$G^\\dagger \\mid_E = \\text{loc } H^E \\tag{D}$$\n\nEquation D is exactly the same as Equation C. This captures the generality of our technique: given an existing top-down MPST system, first, we extend its syntax to hybrid types and generalise projection to sets of participants; then we isolate the inter-component communication of each protocol with the localiser; and, finally, we can state compatibility, prove compositionality, and achieve distributed protocol specification. Such general design gives a clear advantage to our theory, with respect to the dual approach from previous work [Barbanera et al. 2021; Stolte et al. 2021].\n\n**Example 5.7 (Compatibility Through Projection VS Input/Output Matching).** We consider the following three-component system $H_1, H_2, H_3$, with $G^\\dagger$ for compatibility.\n\n$$G^\\dagger = \\begin{array}{l} \\text{H}_1 = \\exists \\{p \\rightarrow q(t)\\}; \\text{end}, p \\rightarrow^e s(t^e); s \\rightarrow q(t'); \\text{end} \\end{array} \\quad \\begin{array}{l} \\text{H}_2 = q \\rightarrow q_1(t_1); \\text{end}, s?q(t'); \\text{end} \\end{array} \\quad \\begin{array}{l} \\text{H}_3 = p?s(t^e); s \\rightarrow r(t^r); s!q(t'); \\text{end} \\end{array}$$\n\nIn $H_1$, $p$ makes a choice: on the first branch, it first sends an internal message and then an external one to $q$ in $H_2$; on the other branch $p$ first makes an explicit connection to $s$ in $H_3$ and then sends an internal message. The component $H_2$ (after an internal interaction) is waiting to receive either from $p$ in $H_1$ or from $s$ in $H_2$. The third component $H_3$ is concerned only with the second branch, in case it is chosen by $p$. All types are compatible with respect to $G^\\dagger \\mid_E = \\text{loc } H_1$, with $E_1 = \\{p, p_0\\}$, $E_2 = \\{q, q_1\\}$, and $E_3 = \\{s, r\\}$. Indeed, we can build a well-formed global type for the whole system:\n\n$$G = q \\rightarrow q_1(t_1); \\exists \\{p \\rightarrow p_0(t_0); p \\rightarrow q(t); \\text{end}, p \\rightarrow^e s(t^e); s \\rightarrow^r r(t^r); s \\rightarrow q(t'); p \\rightarrow p_0(t_0); \\text{end}\\}$$\n\nWe focus on $H_2$ and we observe that, in the intersection of inputs, $q$ is waiting to receive from $p$ in $H_1$, on the first branch, and from $s$ in $H_3$, on the second. Therefore, a match for inputs in $H_2$ cannot happen solely with outputs of $H_1$, nor solely with outputs of $H_3$. In this case, dual compatibility relations would fail, while, with our approach based on projection, compatibility can be simply stated with respect to the global guidance of $G^\\dagger$, through Equation D.\n6 RELATED WORK\n\nOur work achieves protocol compositionality in MPST top-down systems, namely those systems where the communication protocol is explicitly described as a global type and, subsequently, from the projection of it, local types are obtained for implementation. We organise this section as a progressive discussion of related work, with respect to our paper, from more distant to closer.\n\nMPST Alternatives to the Top-Down Approach. Since their first appearance [Honda et al. 2008], MPST have evolved into a variety of frameworks for the specification and the verification of concurrency, often beyond the original top-down approach. The works of Lange and Tuosto [2012] and Deniélou and Yoshida [2013] explicitly give algorithms for the synthesis of global types from communicating finite-state machines, while Lange et al. [2015] propose a similar method to build graphical choreographies, expressed as global graphs. Scalas and Yoshida [2019] develop a framework where global types are not necessary, relying instead on model- and type-checking techniques for verifying safety properties of collections of local types. The advantage of such approaches is that they offer analysis for pre-existent systems. However, before the need to hierarchically design a new communicating system, the top-down approach enables a high-level specification of the system that guarantees safe interactions of distributed implementations. The top-down approach has seen a variety of tools and implementations, e.g., [Carbone and Montesi 2013; Castro-Perez et al. 2021; Gheri et al. 2022; Honda et al. 2011; Neykova and Yoshida 2019; Yoshida et al. 2013, 2021] and it has been investigated beyond MPST [Barbanera et al. 2020a; Montesi 2013]. Recent research (e.g., [Cledou et al. 2022; Glabbeek et al. 2021; Jacobs et al. 2022; Lagaillardie et al. 2022]) has kept exploring the possibilities offered by an explicit design of systems through protocol specification. Our work adds compositionality to top-down protocol specification.\n\nProtocol Flexibility and Modularity beyond MPST. Caires and Vieira [2009]; Padovani et al. [2014] do not address protocol compositionality, but, in defining conversation types, the authors combine global and local constructs in the same syntax, for a flexible specification: messages can be scheduled, while participants can be at first left unspecified, thus allowing for interleaving of sessions. In the context of reactive programming, Carbone et al. [2018]; Savanovic et al. [2020] propose a technique for modular design: a communicating system is specified in terms of components, each (composite) component contains a choreography (or, protocol) and for each role in the protocol a new implementation (component) is specified. Intuitively speaking, each component comes with an input/output interface allowed by the protocol, so to keep track of data-flow dependencies. Montesi and Yoshida [2013] develop a compositional technique for choreographic programming: the specification of partial choreographies is allowed, i.e., the implementation of some of the roles can be left unspecified. These roles can be implemented by a different choreography at a later time; compatibility is achieved through an additional typing relation on choreographies, which relies both on global and local types. All the above work modifies the essence of the protocol structure. Our theory differs from it, first, because our compatibility condition (Equation C) relies on projection, instead of dual input/output matching. Then, compositionality based on hybrid types retains the simplicity of traditional MPST protocol structure: the result of composition is a well-formed global type and no new semantics need to be developed. Thanks to such semantics preservation and our novel compatibility, our techniques are general enough to be applied to traditional MPST (§3 and §4), as well as to more expressive specifications (§5.4).\n\nModular Global Types through Nesting. Global types are choreographic objects and, hence, originally [Honda et al. 2008] intended as standalone entities. Given their monolithic nature, techniques for making them more flexible have been proposed very early on; e.g., Demangeon and Honda [2012] describe a methodology for nesting global types, via calls to a subprotocol from a parent\nprotocol. Tabareau et al. [2014] propose an alternative approach to nesting protocols, by extending the syntax of global and local types with *aspects* [Kiczales et al. 1997]. Demangeon et al. [2015] also explore nesting techniques for global types, and apply these to extend the Scribble protocol description language [Honda et al. 2011; Neykova and Yoshida 2019; Yoshida et al. 2021] with interruptible interactions. Our work does not establish a parent/offspring relation, but it explores direct composition of subprotocols treated as peers.\n\n**State of The Art of Direct Composition of MPST Protocols.** To the best of our knowledge, only Barbanera et al. [2021] and Stolze et al. [2021] investigate the direct composition of protocols for MPST, so that *the result of composition is a well-formed global type*. Our development differs from this work, in primis, because of its semantics preservation: in our theory, global types are exactly as in traditional MPST theories (e.g., [Denielou and Yoshida 2013]); thus, our compositionality is immediately compatible with those and benefits from their semantics results. Furthermore, our theory can compose more than two protocols (missing in [Barbanera et al. 2021]) and captures the full expressiveness of MPST, including parallel composition and recursion (missing in [Stolze et al. 2021]). Ultimately, our compatibility (Equation C) overcomes the limitations of dual input/output matching, on which both Barbanera et al. [2021] and Stolze et al. [2021] rely: our theory is general enough to be applied to more sophisticated MPST systems (§5.4, Example 5.7). Below we expand on the significance of our contribution, with respect to this related work, with detailed examples.\n\nIn [Barbanera et al. 2021], the composition of two global types is achieved with gateways [Barbanera et al. 2018, 2019, 2020b]: two participants, one for each subprotocol (global type), are selected as forwarders (gateways) for communicating with the other; if the subprotocols are compatible, with respect to the gateway choice, they can be composed into a more general global type. The central difference between our design and [Barbanera et al. 2021] is the “interface” through which subprotocols communicate. Instead of gateways, hybrid types use local constructs for inter-component interactions and, instead of a dual input/output matching, they rely on projection for compatibility. Thus, we can safely combine two or more protocols at once. Concretely, we consider the following example involving three subprotocols, described as global types with gateways.\n\n\\[ G_1 = p \\rightarrow h_2 : \\ell.p \\rightarrow q : \\ell.h_3 \\rightarrow q : \\ell.end \\quad G_2 = k_1 \\rightarrow r : \\ell.s \\rightarrow r : \\ell.r \\rightarrow k_3 : \\ell.end \\]\n\n\\[ G_3 = t \\rightarrow u : \\ell.u \\rightarrow l_1 : \\ell.l_2 \\rightarrow u : \\ell.end \\]\n\nWe identify \\((h_2, k_1), (h_3, l_1),\\) and \\((k_3, l_2)\\) as gateways; we choose the first one and compose.\n\n\\[ G_1 \\upharpoonright h_2 \\leftrightarrow k_1 \\quad G_2 = p \\rightarrow h_2 : \\ell.h_2 \\rightarrow k_1 : \\ell.k_1 \\rightarrow r : \\ell.p \\rightarrow q : \\ell.h_3 \\rightarrow q : \\ell.s \\rightarrow r : \\ell.r \\rightarrow k_3 : \\ell.end \\]\n\nThe next steps of composition should happen between \\(h_3\\) and \\(l_1\\), and between \\(k_3\\) and \\(l_2\\). Applying again gateway-composition does not work: after a first step (e.g., using \\(h_3\\) and \\(l_1\\)) we would be left with a single global type, i.e., no two types left to compose (e.g., using \\(k_3\\) and \\(l_2\\)). While we could try simultaneous composition for more than one pair of gateways at once, the simple example in [Barbanera et al. 2021], Section 11, shows how this extension is unsound and could lead to deadlocked systems. Another naïve attempt to improve on gateway composition is the following: we force \\(G_1\\) and \\(G_2\\) to have the same participant for communicating with \\(G_3\\) (relaxing the condition from [Barbanera et al. 2021], where participants in two composing global types must be distinct):\n\n\\[ G_1' = p \\rightarrow h : \\ell.1 \\rightarrow p : \\ell.end \\quad G_2' = k \\rightarrow q : \\ell.q \\rightarrow 1 : \\ell.end \\]\n\n\\[ G_3' = t \\rightarrow r : \\ell.r \\rightarrow t : \\ell.end \\]\n\nThe communication is supposed to happen between \\(h\\) and \\(k\\), and between \\(l\\) and \\(t\\). If we allow non-distinct participants in distinct global types, however, it is not immediate to achieve a well-defined gateways compositionality. For example, the order in which we compose plays a key role: while \\((G_2 \\leftrightarrow h G_1)_1 \\rightarrow t G_3\\) is well defined, \\((G_1 \\leftrightarrow k G_2)_1 \\rightarrow t G_3\\) is not. Also, associativity would not hold: we cannot compose \\(G_3\\) with any of \\(G_1\\) and \\(G_2\\) and then finish composing with the remaining one.\nWe specify the system above in terms of hybrid types: in place of gateways, we use local constructs for inter-component communication (highlighted), and we give the type $G^\\dagger$ for compatibility.\n\n$$\n\\begin{align*}\nH_1 &= p!r; \\ell.p \\rightarrow q : \\ell.u?q; \\ell.end \\\\\nH_2 &= p?r; \\ell.s \\rightarrow r : \\ell.r!u; \\ell.end \\\\\nH_3 &= t \\rightarrow u : \\ell.u; \\ell.end \\\\\nG^\\dagger &= p \\rightarrow r : \\ell.u \\rightarrow q : \\ell.r \\rightarrow u : \\ell.end\n\\end{align*}\n$$\n\nFor all components, compatibility $C$ holds and our theory can compose the three protocols into a well-formed global type (Corollary 4.10), thus overcoming the binary limitation of gateways.\n\nStolze et al. [2021], develop a binary compatibility relation that partially improves on [Barbanera et al. 2021]: they can compose more than two types, but put severe restrictions on the syntax. Global types in [Stolze et al. 2021] are inductive, but with no recursion and no parallel construct, thus making our work (and traditional MPST in general) strictly more expressive. The key role of parallel composition for an inductive syntax is discussed in [Glabbeek et al. 2021] (Example 13 and following paragraph) and in §5.1. Recursion is paramount for expressiveness in MPST [Coppo et al. 2015; Honda et al. 2008, 2016; Yoshida and Gheri 2020]; it allows typing processes with loops and it is omnipresent in real-world protocols (e.g., see §5.2 and §5.3). As for semantics, recursion allows for infinite executions and is a key element in the correspondence between local types and communicating finite-state machines [Deniélou and Yoshida 2013], on which practical implementations of the popular Scribble protocol language are based [Honda et al. 2011; Hu and Yoshida 2016; Neykova and Yoshida 2019; Yoshida et al. 2013, 2021]. Also, recursion (in combination with branching) is among the most delicate aspects of MPST (see, e.g., Observation 3 in [Glabbeek et al. 2021] or Definition B.1 and the following well-formedness lemmas in Appendix B.1). E.g., the recursive types $H_1 = \\mu X.p \\rightarrow q : \\ell_1.p!r; \\ell.X$ and $H_2 = \\mu X.p?r; \\ell.s \\rightarrow r : \\ell_2.X$, are composable both with gateways [Barbanera et al. 2021] and with our theory ($G^\\dagger = \\mu X.p \\rightarrow r : \\ell.X$ for compatibility), but they cannot be expressed in [Stolze et al. 2021].\n\nIn summary, our theory allows composing two or more subprotocols into a well-formed global type, while retaining full expressiveness of MPST, thus improving on the state of the art [Barbanera et al. 2021; Stolze et al. 2021]. Furthermore, previous work focuses on dual input/output matching, which makes it inapplicable to more expressive MPST systems, where instead, to the best of our knowledge, our novel compatibility $C$ is the first notion to succeed (see §5.4, Example 5.7). We observe that, as it happens for the extension of binary session types to multiparty session types, when relying on projection instead of duality, we commit to the specification of one more global object (what we called $G^\\dagger$), but, in return, we obtain full multiparty compatibility.\n\n7 FUTURE WORK\n\nThe first envisioned application for our compositionality theory is its integration with practical protocol design languages, such as Zooid [Castro-Perez et al. 2021] or Scribble [Honda et al. 2011; Yoshida et al. 2013, 2021]. In what follows we briefly describe how this integration can be realised.\n\nIn the past ten years, Scribble has been employed as the protocol language of multiple toolchains, supporting different programming languages and integrating a variety of expressive features [Castro et al. 2019; Gheri et al. 2022; Honda et al. 2011; Hu and Yoshida 2017; Miu et al. 2021; Neykova et al. 2018; Neykova and Yoshida 2019; Scalas et al. 2017; Yoshida et al. 2013, 2021; Zhou et al. 2020]. Independently of the specific implementation, the Scribble toolchain is generally designed as follows.\n\n(1) The designer specifies the communication protocol (a global type $G$) in Scribble.\n\n(2) $G$ is projected onto local types $L_1, \\ldots, L_n$—or, equivalently, their representation as CFSMs [Deniélou and Yoshida 2013].\n\n(3) From local types, APIs for the distributed implementation of all participants are generated (following the approach of Hu and Yoshida [2016]).\nThrough API implementation, the communication for the multiparty system is MPST certified and does not get stuck (semantic guarantees hold). Thanks to its semantics-preserving features and its backwards compatibility with existing MPST systems, our compositionality framework can be integrated with Scribble toolchains, with minimal effort. First, we will extend the Scribble protocol design language to the syntax of hybrid types (Definition 3.3)—of which global types are a particular case—with constructs $p!q$ and $p?q$. Then, we will implement the localiser (Definition 3.8) and extend projection to Definition 3.6; here compatibility with previous implementations is guaranteed by the considerations in Remark 3.7: Definition 3.6 generalises traditional MPST projection (Definition 3.2). Finally, we will implement checks for $isGlobal(G^i)$ and compatibility $c (G^i \\mid E = \\text{loc } H^E)$. With these simple changes, we will endow Scribble with compositionality, thus enabling distributed protocol specification. “Compositional Scribble” will look as follows.\n\n1. Multiple designers give $H_1, \\ldots, H_N$ in a distributed fashion and a chief designer specifies $G^i$, as hybrid types.\n\n2. Internal checks are performed for $isGlobal(G^i)$ and compatibility $c$.\n\n3. Each $H_i$ is projected onto local types $L_1, \\ldots, L_n$, or, equivalently, their representation as CFMSMs [Denielou and Yoshida 2013].\n\n4. From local types, APIs for the distributed implementation of all participants are generated.\n\nWe observe that, thanks to our theory, the checks in (2) are enough to guarantee the existence of a well-formed global type for the whole system, without the need for explicitly building back such type (see also Corollary 4.10 and Remark 4.12). Moreover, since projection is preserved (Theorem 4.9 and Corollary 4.10), local types are the same as in traditional MPST: not only do semantic guarantees still hold, but so does the correspondence between local types and CFMSMs in [Denielou and Yoshida 2013].\n\nWith respect to traditional Scribble, nothing changes for the user, apart from the added functionality of distributed protocol specification: the safe distributed implementation of all participants is still enabled, but, now, also protocols can be specified in a distributed fashion, in terms of their components (as hybrid types $H_1, \\ldots, H_N$).\n\nBeyond its integration with existing protocol design languages, we plan to build on this work in different directions. In Section 5.4, we have shown the potential of our approach to compositionality, by adapting it to an MPST formalism that extends the traditional syntax of global types to include the advanced features of delegation and explicit connections. Similarly, beyond our core compositionality for global types, we envision future applications to the wide variety of MPST systems (e.g., featuring fault tolerance [Viering et al. 2021], timed specification [Bocchi et al. 2014], refinements [Zhou et al. 2020], cost awareness [Castro-Perez and Yoshida 2020], or exception handling [Lagaillardie et al. 2022]) and, orthogonally, future extensions that add flexibility to compositionality itself (e.g., by factoring in renaming mechanisms for participants [Jacobs et al. 2022]). Another promising perspective is the application of our techniques beyond MPST, to other protocol-design formalisms based on projection, e.g., choreography automata [Barbanera et al. 2020a; Gheri et al. 2022] or choreographic programming [Montesi 2013].\n\n8 CONCLUSION\n\nWe have developed a “compositionality-through-projection” technique that allows the distributed specification of MPST protocols, in terms of hybrid types (Definition 3.3). Our work neatly improves on the state of the art, by allowing for composition of more than two protocols, while retaining the full expressiveness of global types. Our results (Corollaries 4.10 and 5.1) guarantee correctness and make our theory compatible with existing MPST systems (semantics preservation). Our novel compatibility relation (Equation C), based on generalised projection and localiser (Definitions\novercomes the limitations of dual input/output matching and it is general enough to capture extensions beyond traditional MPST (e.g., to delegation and explicit connections §5.4).\n\nACKNOWLEDGMENTS\nWe thank Franco Barbanera, Mariangiola Dezani-Ciancaglini, Francisco Ferreira, and Franco Raimondi for the in-depth conversations and useful comments on the preliminary versions of the paper. This work is supported by EPSRC EP/T006544/2, EP/K011715/1, EP/K034413/1, EP/L00058X/1, EP/N027833/2, EP/N028201/1, EP/T014709/2, EP/V000462/1, EP/X015955/1 and NCSS/EPSRC VeTSS.\n\nREFERENCES\n\n\nA COMMUNICATION PROTOCOL FOR THE COMPANY, FROM OVERVIEW\n\nIn Figure 9 the communication protocol for the whole company from §2.\n\nB DEFINITIONS AND PROOFS\n\nB.1 Compositionality: Building Back a Subprotocol into a Global One\n\nDefinition B.1 (Guardedness for Hybrid Types). We define guardedness as a predicate on hybrid types, with the following inductive rules:\n\n- guarded end\n- guarded X \\( \\forall i \\in I. \\) guarded \\( H_i \\)\n- guarded \\( (p!q; \\{t_i(S_i).H_i\\}_{i \\in I}) \\)\n- not_pure_rec X H guarded H\n- guarded (\\( \\mu X.H \\)) \\( \\forall i \\in I. \\) guarded \\( H_i \\)\n- guarded \\( (p?q; \\{t_i(S_i).H_i\\}_{i \\in I}) \\)\n- guarded \\( H_1 \\) guarded \\( H_2 \\)\n- guarded \\( (H_1|H_2) \\) \\( \\forall i \\in I. \\) guarded \\( H_i \\)\n- guarded \\( (p \\rightarrow q; \\{t_i(S_i).H_i\\}_{i \\in I}) \\)\n\nwhere not_pure_rec X H means that H is different from \\( \\mu Y_1 \\ldots \\mu Y_n.X \\) and also \\( H \\neq X \\).\n\nThe above definition is adapted from the Coq-mechanised MPST metatheory in [Castro-Perez et al. 2021] (Definitions A.2 and A.10 in the appendix of the extended version of the paper [Castro-Perez et al. 2021]).\n\nThe next six lemmas are preliminary results, adapted from classic multiparty session type theories. They are needed for the base cases of induction in the build-back theorem (Theorem B.17). For all the lemmas below, the proofs go by structural induction.\n\nLemma B.2 (Projection and Closed Types). \\( H \\upharpoonright_E \\) is closed iff \\( H \\) is closed.\n\nLemma B.3 (Localiser and Closed Types). loc \\( H \\) is closed iff \\( H \\) is closed.\nLEMMA B.4 (Projection onto Internal Participants). If \\( \\text{ipart}(H) \\subseteq E \\) then \\( H \\upharpoonright_E = H \\).\n\nLEMMA B.5 (Projection onto Disjoint Participants (1)). If \\( \\text{ipart}(H) \\cap E' = \\emptyset \\) and \\( H \\) is closed, then \\( H \\upharpoonright_{E'} = \\emptyset \\).\n\nLEMMA B.6 (Projection onto Disjoint Participants (2)). If \\( \\text{ipart}(H) \\cap E' = \\emptyset \\) and \\( H \\) is not closed, then \\( H \\upharpoonright_{E'} = \\mu Y_1, \\ldots, \\mu Y_n \\cdot X \\) (if such projection exists).\n\nLEMMA B.7 (Projection is Guarded). If \\( H \\upharpoonright_E \\) is guarded (if it is defined and \\( H \\) is guarded).\n\nThe following definitions and lemmas introduce objects and results needed for the main algorithm and ultimately for proving Theorem B.17. They guarantee the good behaviour of our compositionality algorithm, with respect to full merge ([Deniélou and Yoshida 2013] and Definition 3.6 in this paper) for projection and its “dual” for the localiser (Definition 3.8 in this paper).\n\nThe binary unmerge for localiser \\( \\text{unmL}^{\\text{bin}} \\) takes a type \\( H^\\uparrow \\) (first argument) and “unmerges” it, according to the structure of two other types \\( H_1^L \\) and \\( H_2^L \\) (second and third arguments); thus \\( \\text{unmL}^{\\text{bin}} \\) returns a pair of types, the unmerged components of \\( H^\\uparrow \\). The non-binary version of the unmerge for localiser \\( \\text{unmL} \\) is defined by iterating the binary one, thus allowing for unmerging into \\( n \\) types. The role of this function is clarified by Lemma B.11.\n\nTo correctly define such function we need an auxiliary function that handles the case in which a projection merge is equal to a localiser one: \\( \\bigsqcup_{i \\in I} H_i^L = \\bigsqcup_{j \\in J} H_j^L \\). In this case we want to obtain, for all \\( i \\in I, j \\in J \\), \\( H_{L}^{L \\cdot i} \\) such that \\( \\bigsqcup_{L \\cdot i} H_{L}^{L \\cdot i} = H_i^L \\) and \\( \\bigsqcup_{L \\cdot j} H_{L}^{L \\cdot j} = H_j^L \\).\n\n**Definition B.8 (Localiser Unmerge for Projection Merge).** The partial function binary localiser-unmerge for projection merge \\( \\text{unmL}^{\\text{bin}} H_1^L \\rightarrow H_2^L \\rightarrow H_1^L \\rightarrow H_2^L \\) is recursively defined by the following equations, whenever the recursive call is defined (we use \\( \\pi_1 \\) and \\( \\pi_2 \\) to indicate standard pair projections):\n\n\\[\n\\text{unmL}^{\\text{bin}} \\text{end} \\text{end} \\text{end} = ((\\text{end}, \\text{end}), (\\text{end}, \\text{end}))\n\\]\n\n\\[\n\\text{unmL}^{\\text{bin}} \\mu X.H_1^L \\rightarrow H_2^L \\rightarrow H_2^L = ((\\mu X.H_1^L), (\\mu X.H_2^L), (\\mu X.H_1^L, \\mu X.H_2^L))\n\\]\n\nwhere \\( H_m^L = \\pi_1(\\pi_m(\\text{unmL}^{\\text{bin}} H_1^L \\rightarrow H_2^L)) \\) for \\( n, m = 1, 2 \\).\n\n\\[\n\\text{unmL}^{\\text{bin}} (p \\rightarrow q) = ((\\ell_1(S_1).H_1^L), \\ell_1(S_1).H_1^L) \\rightarrow \\{p \\rightarrow q\\} ; \\{q \\rightarrow l(S_1).H_1^L\\} \\rightarrow \\{p \\rightarrow q\\} ; \\{q \\rightarrow l(S_1).H_1^L\\} = \\{p \\rightarrow q\\} ; \\{q \\rightarrow l(S_1).H_1^L\\} \\rightarrow \\{p \\rightarrow q\\} ; \\{q \\rightarrow l(S_1).H_1^L\\}\n\\]\n\nwhere, for \\( n, m = 1, 2 \\), \\( H_m^L = \\pi_1(\\pi_m(\\text{unmL}^{\\text{bin}} H_1^L \\rightarrow H_1^L)) \\) if \\( i \\in J \\cup K \\).\n\n**Definition B.8 (Localiser Unmerge for Projection Merge).** The partial function localiser-unmerge for projection merge \\( \\text{unmL} \\) \\( L_p L_L \\) takes as input two lists of types instead of two pairs. It returns a tuple of lists: if \\( L_p = [H_1^L, \\ldots, H_n^L] \\) and \\( L_L = [H_1^L, \\ldots, H_m^L] \\) the result list is of the kind \\( ([H_1^L, \\ldots, H^n_m]) \\) (\\( \\pi_i \\) indicate the standard projection\n\nof the $i$-th component of the tuple). unmLP is defined by recursion (on the sum of the lengths of $L_P$ and $L_L$) by the following equations.\n\n$$\\text{unmLP} \\left[ \\left[ \\right] \\right] L_L = \\left[ \\left[ \\right] \\right]$$\n$$\\text{unmLP} \\left[ H^T \\right] L_L = \\left[ \\left[ L_L \\right] \\right]$$\n$$\\text{unmLP} \\left[ H^T_1, H^T_2 \\right] L_L = \\begin{cases} \\left( \\left[ \\right], \\left[ \\right] \\right) & \\text{if } L_L = \\left[ \\right] \\\\\n\\left( \\left[ \\pi_1(\\pi_1(\\text{unmL}^\\text{bin} H^T_1 H^T_1 H^L_1 H^L_1)), \\pi_1(\\pi_2(\\text{unmL}^\\text{bin} H^T_1 H^T_1 H^L_1 H^L_1)) \\right] \\right) & \\text{if } L_L = \\left[ H^L_1 \\right] \\\\\n\\left( \\left[ \\pi_1(\\pi_1(\\text{unmL}^\\text{bin} H^T_1 H^T_1 H^L_1 H^L_1)), \\pi_2(\\pi_1(\\text{unmL}^\\text{bin} H^T_1 H^T_1 H^L_1 H^L_1)) \\right] \\right) & \\text{if } L_L = \\left[ H^T_1, H^L_2 \\right] \\\\\n\\left( \\left[ \\pi_1(U) \\# L^1, \\pi_1(U) \\# L^2 \\right] \\right) & \\text{if } L_L = \\left[ H^T_1, H^T_2 \\right] \\\\\n\\left( \\left[ \\pi_1(U) \\# L^1, \\pi_1(U) \\# L^2 \\right] \\right) & \\text{if } L_L = \\left[ H^T_1, H^T_2 \\right]\n\\end{cases}$$\n\n$$\\text{unmLP} \\left[ H^T_1, H^T_2, \\ldots, H^T_n \\right] L_L = \\left( L^1, \\pi_1(\\text{unmL} \\left[ H^T_2, \\ldots, H^T_n \\right] L^2), \\ldots, \\pi_{n-1}(\\text{unmL} \\left[ H^T_2, \\ldots, H^T_n \\right] L^2) \\right)$$\n\nwhere, for $i = 1, 2$, $L^i = \\text{unmL} \\left[ H^T_i, (\\sqcup_{k=2,\\ldots,n} H^L_k) \\right]$ $L_L$.\n\n**Lemma B.9.** We are given hybrid types $H^T_1, \\ldots, H^T_n$ and $H^L_1, \\ldots, H^L_m$, such that $\\sqcup_{i=1,\\ldots,n} H^T_i = \\sqcup_{j=1,\\ldots,m} H^L_j$.\n\nThen unmLP $\\left[ H^T_1, \\ldots, H^T_n \\right] \\left[ H^L_1, \\ldots, H^L_m \\right]$ is defined and, if we set\n\n$$\\text{unmLP} \\left[ H^T_1, \\ldots, H^T_n \\right] \\left[ H^L_1, \\ldots, H^L_m \\right] = \\left( \\left[ H^L_1, \\ldots, H^L_m \\right] \\right),$$\n\nwe have that:\n\n- $\\sqcup_{i=1,\\ldots,n} H^L_i = H^T_i$, for all $i = 1, \\ldots, n$, and\n- $\\sqcup_{j=1,\\ldots,m} H^L_j = H^T_j$, for all $j = 1, \\ldots, n$.\n\n**Proof.**\n\n- We first prove the base cases, in particular the case in which $n = 2$ and $m = 2$ (formally we first prove the result for unmL$^{\\text{bin}}$). This is done by structural induction on $H^T_1$, exploiting the hypothesis and the inductive nature both of $\\sqcup$ and $\\sqcup^T$.\n- We conclude by induction on $n + m$, by following the definition of unmLP.\n\n**We now define the unmerge for the localiser (Definition B.10) and ensure that it has the desired behaviour (Lemma B.11).**\n\n**Definition B.10 (Localiser Unmerge).** The partial function binary unmerge for localiser unmL$^{\\text{bin}}_E$ $H^T_1 H^L_1 H^T_2$ is defined if $\\text{ipart}(H^T_1) \\cup hpart H^L_1 \\subseteq E$ by the following equations, by recursion on depth($H^T_1$), whenever the recursive call is defined (we use $\\pi_1$ and $\\pi_2$ to indicate standard pair projections; we also make implicit the\ndependency on \\( E \\) using the notation unml\\textsuperscript{bin} instead of \\( \\textit{ublE} \\):\n\n\\[\n\\text{unml}^{\\bin} \\text{end } H^{\\bin}_{1} H^{\\bin}_{2} = (\\text{end}, \\text{end})\n\\]\n\n\\[\n\\text{unml}^{\\bin} X H^{\\bin}_{1} H^{\\bin}_{2} = (X, X)\n\\]\n\n\\[\n\\text{unml}^{\\bin} (\\mu X. H^{\\bin}) H^{\\bin}_{1} H^{\\bin}_{2} = \\begin{cases} \n(\\mu X. \\pi_{1}(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2}), \\mu X. \\pi_{2}(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2})) & \\text{if } H^{\\downarrow}_{1} = \\mu X. H^{\\downarrow}_{1} \\text{ and } H^{\\downarrow}_{2} = \\mu X. H^{\\downarrow}_{2} \\\\\n(\\mu X.H^{\\uparrow}, \\mu X.H^{\\uparrow}) & \\text{if } H^{\\downarrow}_{1} = H^{\\downarrow}_{2} = \\text{end}\n\\end{cases}\n\\]\n\n\\[\n\\text{unml}^{\\bin} (H^{\\downarrow}_{1} H^{\\downarrow}_{2}) H^{\\bin}_{1} H^{\\bin}_{2} = \\begin{cases} \n((\\pi_{1}(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2})), (\\pi_{2}(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2})), (\\text{set}(H^{\\downarrow}_{2}))) & \\text{if } E \\cap \\text{ipart}(H^{\\downarrow}_{2}) = \\emptyset \\\\\n(\\text{set}(H^{\\downarrow}_{2})) & \\text{if } E \\cap \\text{ipart}(H^{\\downarrow}_{2}) = \\emptyset\n\\end{cases}\n\\]\n\n\\[\n\\text{unml}^{\\bin} (q \\ell) (\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2}) = (q \\ell)(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2})\n\\]\n\n\\[\n\\text{unml}^{\\bin} (\\text{set}(H^{\\downarrow}_{2})) = (\\text{set}(H^{\\downarrow}_{2}))\n\\]\n\n\\[\n\\text{unml}^{\\bin} (p \\ell q) (\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2}) = (p \\ell q)(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2})\n\\]\n\n\\[\n\\text{unml}^{\\bin} \\text{unmerge for localiser } \\text{unml} H^{\\uparrow} L = \\text{undefined otherwise}\n\\]\n\nGiven a set of participants \\( E \\), the partial function \\( \\text{unmerge} \\) for localiser \\( \\text{unml} H^{\\uparrow} L \\) (again we drop the dependency on \\( E \\) in the notation) is defined if \\( \\bigcup_{H^{\\uparrow} \\in \\text{set}(L)} \\text{ipart}(H^{\\uparrow}) \\) by the following equations, by recursion on the list of hybrid types \\( L \\), whenever the recursive call is defined:\n\n\\[\n\\text{unml} H^{\\uparrow} [] = \\text{undefined}\n\\]\n\n\\[\n\\text{unml} H^{\\uparrow} [H^{\\uparrow}] = [H^{\\uparrow}]\n\\]\n\n\\[\n\\text{unml} H^{\\uparrow} [H^{\\uparrow}_{1} H^{\\uparrow}_{2}] = [\\pi_{1}(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2}), \\pi_{2}(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} H^{\\downarrow}_{2})]\n\\]\n\n\\[\n\\text{unml} H^{\\uparrow} (H^{\\downarrow}_{1} \\#(H^{\\downarrow}_{2} \\#L)) = \\pi_{1}(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} (\\text{set}(H^{\\downarrow}_{2} \\#L)) \\# \\text{unml} \\pi_{2}(\\text{unml}^{\\bin} H^{\\uparrow}, H^{\\downarrow}_{1} (\\text{set}(H^{\\downarrow}_{2} \\#L))) (H^{\\downarrow}_{2} \\#L)\n\\]\nWe observe that length \\((\\text{unmL} \\ H^+_t L) = \\text{length} \\ L\\) and that depth\\((H^+_t) = \\text{depth}(H^+_t)\\), where \\(H^+_t\\) is the \\(t\\)-th element of the list unmL \\(H^+_1, H^+_2, \\ldots, H^+_n\\) (when defined).\n\n**Lemma B.11 (Unmerge for Localiser).** We fix a set of participants \\(E\\), and we are given hybrid types \\(H^+_t\\) and \\(H^+_{t'}\\), \\(t = 1, \\ldots, n\\), such that:\n\n1. \\(\\text{ipart}(H^+_t) \\subseteq E\\), for all \\(t = n\\),\n2. \\(\\text{epart}(H^+_t) \\cap E = \\emptyset\\),\n3. \\(H^+_t \\upharpoonright E = \\bigcup_{i=1}^n H^+_i\\); then, for all \\(t = 1, \\ldots, n\\), we call \\(H^+_t\\) the \\(t\\)-th element of the list unmL \\(H^+_1, H^+_2, \\ldots, H^+_n\\) and we have\n\n\\[\n\\begin{align*}\n(1) & \\quad H^+_t \\upharpoonright E = H^+_t \\\\\n(2) & \\quad \\bigcup_{i=1}^n (H^+_i \\upharpoonright E) = H^+_t \\upharpoonright E, \\text{ for all } E' \\cap E = \\emptyset.\n\\end{align*}\n\\]\n\n**Proof.** Let us first prove the lemma for \\(n = 2\\). In particular, hypothesis (c) gives us \\(H^+_t \\upharpoonright E = H^+_t \\upharpoonright L^2 H^+_2\\). We need to prove the thesis for \\(H^+_1 = \\pi_1(\\text{unmL} \\ H^+_1 H^+_2 H^+_2)\\) and \\(H^+_2 = \\pi_2(\\text{unmL} \\ H^+_1 H^+_2 H^+_2)\\), namely that \\(H^+_1 \\upharpoonright E = H^+_1 \\upharpoonright L^1 H^+_2,\\) and \\(H^+_2 \\upharpoonright E \\upharpoonright H^+_2 = H^+_2 \\upharpoonright E,\\) for all \\(E' \\cap E = \\emptyset\\). We proceed by induction depth\\((H^+_1) + \\max(\\text{depth}(H^+_1), \\text{depth}(H^+_2))\\).\n\nBase cases \\(H^+_1 = \\text{end}\\) and \\(H^+_2 = X\\) are trivial. Let us consider \\(H^+_1 = \\mu X.H^+_1\\); if \\(H^+_1 \\upharpoonright E = \\text{end}\\) then \\(H^+_1 \\upharpoonright E = \\text{end}\\) and the thesis follows by definition. If \\(H^+_1 \\upharpoonright E = \\mu X.(H^+_1 \\upharpoonright E)\\) then \\(H^+_1 = \\mu X.H^+_1\\) and the thesis follows by applying induction hypothesis to \\(H^+_1, H^+_1,\\) and \\(H^+_2\\).\n\nFor case \\(H^+_1 = H^+_1 \\upharpoonright L^2 H^+_2,\\) we can assume without loss of generality \\(H^+_1 \\upharpoonright E = H^+_1 \\upharpoonright L^1 E,\\) hence \\(\\text{unmL} (H^+_1 \\upharpoonright H^+_2) H^+_1 H^+_2 = ((\\pi_1(\\text{unmL} \\ H^+_1 \\upharpoonright H^+_1) H^+_1 H^+_2)) \\upharpoonright H^+_2, (\\pi_2(\\text{unmL} \\ H^+_1 \\upharpoonright H^+_1 H^+_2)) \\upharpoonright H^+_2).\\) We conclude by induction hypothesis.\n\nWe are left with the message cases \\(p \\downarrow q; \\{ \\ell(S_i).H^+_i \\}_{i \\in I}, p \\downarrow q; \\{ \\ell(S_i).H^+_i \\}_{i \\in I},\\) and \\(p \\rightarrow q; \\{ \\ell(S_i).H^+_i \\}_{i \\in I}.\\) These are all analogous and we will see in detail only \\(H^+_1 = p \\rightarrow q; \\{ \\ell(S_i).H^+_i \\}_{i \\in I},\\) which is the most general as it can project on every message construct: \\(p \\rightarrow q; \\ldots, p \\downarrow q; \\ldots,\\) and \\(p \\downarrow q; \\ldots\\)\n\n\\[\n\\{\\{p, q\\} \\subseteq E\\} \\text{ then } H^+_1 \\upharpoonright E = p \\rightarrow q; \\{\\ell(S).H^+_1 \\upharpoonright E\\}_{i \\in I} \\text{ and, since } \\upharpoonright L^2 \\text{ cannot output a global message } p \\rightarrow q; \\ldots, \\text{ by hypothesis (c) the thesis holds vacuously.}\n\\]\n\n\\[\n[p \\in E \\land q \\notin E] \\text{ We have (hypothesis (c)) } H^+_1 \\upharpoonright E = H^+_1 \\upharpoonright L^1 H^+_2, \\text{ namely}\n\\]\n\n\\[\np \\downarrow q; \\{\\ell(S).H^+_1 \\upharpoonright E\\}_{i \\in I} = p \\downarrow q; \\{\\ell(S).H^+_1 \\upharpoonright E\\}_{j \\in J} \\upharpoonright L^1 p \\downarrow q; \\{\\ell(S).H^+_2 \\}_{k \\in K} \\text{ with } J \\cup K = I.\n\\]\n\nWe observe that\n\n- if \\(i \\in J \\cap K\\) then \\(H^+_1 \\upharpoonright E = H^+_1 \\upharpoonright i,\\)\n- if \\(i \\in K \\setminus J\\) then \\(H^+_1 \\upharpoonright E = H^+_2 \\upharpoonright i,\\) and\n- if \\(i \\in J \\setminus K\\) then \\(H^+_1 \\upharpoonright E = H^+_1 \\upharpoonright L^1 H^+_2 i.\\)\n\nAlso, by construction, \\(\\text{unmL} (H^+_1 H^+_2) = (p \\downarrow q; \\{\\ell(S_j).H^+_1 \\}_{j \\in J}, p \\downarrow q; \\{\\ell(S_k).H^+_2 \\}_{k \\in K},\\), with \\(H^+_1 = H^+_1 j \\in J \\cap K, H^+_1 = \\pi_1(\\text{unmL} H^+_1 H^+_2 H^+_2)\\) for \\(j \\in J \\cap K, H^+_2 = H^+_2 k \\in K \\cap J, H^+_2 = \\pi_2(\\text{unmL} H^+_1 H^+_2 H^+_2)\\) for \\(k \\in K \\cap J.\\) We use the notation \\(H^+_1 = \\pi_1(\\text{unmL} \\ H^+_1 H^+_2 H^+_2) = p \\downarrow q; \\{\\ell(S_j).H^+_1 \\}_{j \\in J}\\) and \\(H^+_2 = \\pi_2(\\text{unmL} \\ H^+_1 H^+_2 H^+_2) = p \\downarrow q; \\{\\ell(S_k).H^+_2 \\}_{k \\in K}\\).\n\nIt is immediate, by construction and induction hypothesis, to prove that \\(H^+_1 \\upharpoonright E = H^+_1\\) and that \\(H^+_2 \\upharpoonright E = H^+_2.\\) Let us consider \\(E',\\) such that \\(E' \\cap E = \\emptyset \\land q \\notin E',\\) namely \\(H^+_1 \\upharpoonright E' = \\bigcup_{j \\in J} H^+_1 \\upharpoonright E'\\) and \\(H^+_2 \\upharpoonright E' = \\bigcup_{k \\in K} H^+_2 \\upharpoonright E'.\\) Then\n\n\\[\n(H^+_1 \\upharpoonright E') = \\bigcup_{j \\in J \\cap K} H^+_1 \\upharpoonright E' \\upharpoonright L^1 k \\in K \\cup J \\cup (H^+_1 \\upharpoonright E' \\upharpoonright L^2 \\upharpoonright E').\n\\]\nby associativity and commutativity of merge. We conclude by construction of $H_{i}^{1}$ and $H_{i}^{2}$ and applying induction hypothesis. Now, if $E'$ is such that $E' \\cap E = \\emptyset$ and $q \\in E'$, we have $H_{i}^{1} \\uplus E' = p \\uplus q : \\{ \\ell(S) . (H_{i}^{1} \\uplus E') \\}_{i \\in I}$ and $H_{i}^{2} \\uplus E = p \\uplus q : \\{ \\ell(S) . (H_{i}^{2} \\uplus E') \\}_{i \\in I}$. We conclude by definition of $\\uplus$ (in particular its behaviour with respect to receive constructs) and induction hypothesis.\n\n$[p \\notin E \\text{ and } q \\in E]$ We have (hypothesis $(c)$) $H_{i}^{1} \\uplus E = H_{i}^{1} \\uplus \\uplus H_{i}^{2}$, namely\n\n$$p \\uplus q : \\{ \\ell(S) . (H_{i}^{1} \\uplus E') \\}_{i \\in I} = p \\uplus q : \\{ \\ell(S) . (H_{i}^{1} \\uplus E') \\}_{i \\in I} \\uplus \\uplus p \\uplus q : \\{ \\ell(S) . (H_{i}^{2} \\uplus E') \\}_{i \\in I}.$$ \n\nWe observe that $H_{i}^{1} \\uplus E = H_{i}^{1} \\uplus \\uplus H_{i}^{2}$, and also that, by construction, $\\text{unmL}^{\\text{bin}} H_{i}^{1} \\uplus H_{i}^{2} = (p \\uplus q : \\{ \\ell(S) . H_{i}^{1} \\}_{i \\in I}, p \\uplus q : \\{ \\ell(S) . H_{i}^{2} \\}_{i \\in I})$, with $H_{i}^{1} = \\pi_{1}(\\text{unmL}^{\\text{bin}} H_{i}^{1} \\uplus H_{i}^{2})$ and $H_{i}^{2} = \\pi_{2}(\\text{unmL}^{\\text{bin}} H_{i}^{1} \\uplus H_{i}^{2})$. We use the notation\n\n$$H_{i}^{1} = \\pi_{1}(\\text{unmL}^{\\text{bin}} H_{i}^{1} \\uplus H_{i}^{2}) = p \\uplus q : \\{ \\ell(S) . H_{i}^{1} \\}_{i \\in I}$$\n\nand\n\n$$H_{i}^{2} = \\pi_{2}(\\text{unmL}^{\\text{bin}} H_{i}^{1} \\uplus H_{i}^{2}) = p \\uplus q : \\{ \\ell(S) . H_{i}^{2} \\}_{i \\in I}.$$ \n\nIt is immediate, by construction and induction hypothesis, to prove that $H_{i}^{1} \\uplus E = H_{i}^{1}$ and that $H_{i}^{2} \\uplus E = H_{i}^{2}$. Let us consider $E'$, such that $E' \\cap E = \\emptyset$ and $p \\notin E'$, namely $H_{i}^{1} \\uplus E = \\bigcup_{i \\in I} H_{i}^{1} \\uplus E$ and $H_{i}^{2} \\uplus E = \\bigcup_{i \\in I} H_{i}^{2} \\uplus E$; then\n\n$$(H_{i}^{1} \\uplus E') \\uplus (H_{i}^{2} \\uplus E') = \\bigcup_{i \\in I} (H_{i}^{1} \\uplus E' \\uplus H_{i}^{2} \\uplus E')$$\n\nby associativity and commutativity of merge. We conclude by construction of $H_{i}^{1}$ and $H_{i}^{2}$ and applying induction hypothesis. Now, if $E'$ is such that $E' \\cap E = \\emptyset$ and $p \\in E'$, we have $H_{i}^{1} \\uplus E = p \\uplus q : \\{ \\ell(S) . (H_{i}^{1} \\uplus E') \\}_{i \\in I}$ and $H_{i}^{2} \\uplus E = p \\uplus q : \\{ \\ell(S) . (H_{i}^{2} \\uplus E') \\}_{i \\in I}$. We conclude by definition of $\\uplus$ (in particular its behaviour with respect to send constructs) and induction hypothesis.\n\n$[\\{ p, q \\} \\cap E = \\emptyset]$ We have $H_{i}^{1} \\uplus E = p \\rightarrow q : \\{ \\ell(S) . H_{i}^{1} \\}_{i \\in I} \\uplus E = \\bigcup_{i \\in I} (H_{i}^{1} \\uplus E) = H_{i}^{1} \\uplus \\uplus H_{i}^{2}$. In this case\n\n$$\\text{unmLP}^{\\text{bin}} H_{i}^{1} \\uplus H_{i}^{2} = (p \\rightarrow q : \\{ \\ell(S) . \\pi_{1}(\\text{unmL}^{\\text{bin}} H_{i}^{1} \\uplus H_{i}^{2}) \\}_{i \\in I}, p \\rightarrow q : \\{ \\ell(S) . \\pi_{2}(\\text{unmL}^{\\text{bin}} H_{i}^{2} \\uplus H_{i}^{2}) \\}_{i \\in I}) = (H_{i}^{1}, H_{i}^{2})$$\n\nwhere $\\text{unmLP}^{\\text{bin}} [H_{i}^{1} \\uplus E]_{i \\in I} [H_{i}^{1}, H_{i}^{2}] = ([H_{i}^{1}, H_{i}^{2}])_{i \\in I}$; we set $H_{i}^{1} = \\pi_{1}(\\text{unmL}^{\\text{bin}} H_{i}^{1} \\uplus H_{i}^{2})$ and $H_{i}^{2} = \\pi_{2}(\\text{unmL}^{\\text{bin}} H_{i}^{1} \\uplus H_{i}^{2})$. Thanks to Lemma B.9, we have that $H_{i}^{1} \\uplus \\uplus H_{i}^{2} = H_{i}^{1} \\uplus E$, $\\bigcup_{i \\in I} H_{i}^{1} = H_{i}^{1}$, and $\\bigcup_{i \\in I} H_{i}^{2} = H_{i}^{2}$. We can then apply induction hypothesis to $H_{i}^{1}$ and have that $H_{i}^{1} \\uplus E = H_{i}^{1}$, $H_{i}^{2} \\uplus E = H_{i}^{2}$, and $H_{i}^{1} \\uplus E \\uplus H_{i}^{2} \\uplus E' = H_{i}^{1} \\uplus E'$, for all $i \\in I$ and for $E' \\cap E = \\emptyset$. Let us consider now $H_{i}^{1} \\uplus E$ this is equal to:\n\n$$H_{i}^{1} \\uplus E = \\bigcup_{i \\in I} (H_{i}^{1} \\uplus E) = \\bigcup_{i \\in I} H_{i}^{1} = H_{i}^{1}$$\n\nthanks to what obtained from Lemma B.9 (see above). Analogously for $H_{i}^{2} \\uplus E = H_{i}^{2}$. If $\\{ p, q \\} \\cap E' \\neq \\emptyset$ we have that the projections of $H_{i}^{1}$ and $H_{i}^{2}$ have the same message prefix $p \\rightarrow q$, $p \\uplus q$, or $p \\uplus q$; are one analogous to the other. Let us consider the first one:\n\n$$H_{i}^{1} \\uplus E \\uplus H_{i}^{2} \\uplus E' = p \\rightarrow q : \\{ \\ell(S) . (H_{i}^{1} \\uplus E \\uplus H_{i}^{2} \\uplus E') \\}_{i \\in I}$$\n\nWe conclude thanks to what obtained from induction hypothesis (see above). If $\\{ p, q \\} \\cap E' = \\emptyset$ then\n\n$$H_{i}^{1} \\uplus E \\uplus H_{i}^{2} \\uplus E' = \\bigcup_{i \\in I} H_{i}^{1} \\uplus E \\uplus \\bigcup_{i \\in I} H_{i}^{2} \\uplus E'$$\n\nand we conclude thanks to what obtained from induction hypothesis (see above) and by associativity and commutativity of merge.\nNow, to have the full lemma for \\( t = 1, \\ldots, n \\), for a generic \\( n \\), it is sufficient to proceed by induction on \\( n \\): we observe that the base cases are obvious and the binary case is above. We are left with \\( n \\geq 3 \\), namely:\n\n\\[\n\\text{unm}\\_L \\ H^t \\ [H^t_1, H^t_2, \\ldots, H^t_n] = H^t \\# \\text{unm}\\_L \\ H^t \\ [H^t_2, \\ldots, H^t_n]\n\\]\n\nwith \\( H^t_1 = \\pi_1(\\text{unm}\\_L \\ H^t \\ H^t_1 (\\bigsqcup_{t=2,n} H^t_1)) \\) and \\( H^t \\pi_2(\\text{unm}\\_L \\ H^t \\ H^t_1 (\\bigsqcup_{t=2,n} H^t_1)) \\).\n\nSince we have proved the theorem for the base case and since \\( \\text{unm}\\_L \\ H^t = \\text{unm}\\_L \\ H^t \\ H^t_1 (\\bigsqcup_{t=2,n} H^t_1) \\), we have that \\( H^t_1 \\upharpoonright_E = H^t_1, \\ H^t \\upharpoonright_E = (\\bigsqcup_{t=2,n} H^t_1) \\), and \\( H^t_1 \\upharpoonright_E \\cup H^t \\upharpoonright_E = H^t_1 \\upharpoonright_E \\). In particular \\( H^t \\upharpoonright_E = (\\bigsqcup_{t=2,n} H^t_1) \\) allows us to apply induction hypothesis and we obtain, for \\( \\pi_2(\\text{unm}\\_L \\ H^t \\ H^t_1 (\\bigsqcup_{t=2,n} H^t_1)) = [H^t_2, \\ldots, H^t_n] \\), that \\( H^t_1 \\upharpoonright_E = H^t_1 \\) and that \\( \\bigsqcup_{t=2,n} H^t_1 \\upharpoonright_E = H^t \\upharpoonright_E \\) for \\( E \\cap E = \\emptyset \\), and thus we conclude.\n\n\\[\\Box\\]\n\nThe binary unmerge for projection \\( \\text{unm}\\_P^\\text{bin} \\) takes a type \\( H^P \\) (first argument) and “unmerges” it, according to the structure of two other types \\( H^t_1 \\) and \\( H^t_2 \\) (second and third arguments); thus \\( \\text{unm}\\_P^\\text{bin} \\) returns a pair of types, the unmerged components of \\( H^t \\). The non-binary version of the unmerge for projection \\( \\text{unm}\\_P \\) is defined by iterating the binary one, thus allowing for unmerging into \\( n \\) types. The role of this function is clarified by Lemma B.15.\n\nTo correctly define such function we need an auxiliary function that handles the case in which a localiser merge is equal to a projection one: \\( \\bigsqcup_{i=1}^t H^t_i = \\bigcup_{j \\in E} H^t_j \\). In this case we want to obtain, for all \\( i \\in I, j \\in J \\), \\( H^t \\upharpoonright_j \\) such that \\( \\bigsqcup_{i=1}^t H^t_i \\upharpoonright_j = H^t \\) and \\( \\bigcup_{i \\in I} H^t_i \\upharpoonright_j = H^t \\).\n\n**Definition B.12 (Projection Unmerge for Localiser Merge).** The partial function binary projection-unmerge for localiser merge \\( \\text{unm}\\_P^\\text{bin} \\ H^t_1 H^t_2 H^t_1 H^t_2 \\) is recursively defined by the following equations, whenever the recursive call is defined (we use \\( \\pi_1 \\) and \\( \\pi_2 \\) to indicate standard pair projections):\n\n\\[\n\\begin{align*}\n\\text{unm}\\_P^\\text{bin} & \\quad \\text{end end end end} = ((\\text{end}, \\text{end}), (\\text{end}, \\text{end})) \\\\\n\\text{unm}\\_P^\\text{bin} & \\quad X \\times X \\times X = ((X, X), (X, X)) \\\\\n\\text{unm}\\_P^\\text{bin} & \\quad H^t_1 \\times H^t_2 \\times H^t_1 \\times H^t_2 = ((H^t_1 \\times H^t_2), (H^t_2 \\times H^t_1)) \\\\\n\\text{where} & \\quad H^t_n = \\pi_n(\\pi_n(\\pi_n(\\pi_m(\\text{unm}\\_P^\\text{bin} H^t_1 H^t_2 H^t_1 H^t_2)) \\text{ for } n, m = 1, 2) \\\\\n\\text{unm}\\_P^\\text{bin} & \\quad (p \\cdot q; \\{\\ell(S_i).H^t_i\\}_{i \\in I}) \\cdot (p \\cdot q; \\{k(S_k).H^t_k\\}_{k \\in K}) \\text{ for } J \\cup K = I \\text{ and, for } n, m = 1, 2, H^t_{nm} = \\\\\n\\text{where} & \\quad J \\cup K = I \\text{ and, for } n, m = 1, 2, H^t_{nm} = \\\\\n\\text{unm}\\_P^\\text{bin} & \\quad (p \\cdot q; \\{\\ell(S_i).H^t_i\\}_{i \\in I}) \\cdot (p \\cdot q; \\{k(S_k).H^t_k\\}_{k \\in K}) \\text{ for } J \\cup K = I \\text{ and, for } n, m = 1, 2, H^t_{nm} = \\\\\n\\text{where} & \\quad J \\cup K = I \\text{ and, for } n, m = 1, 2, H^t_{nm} = \\\\\n\\text{unm}\\_P^\\text{bin} & \\quad (p \\cdot q; \\{\\ell(S_i).H^t_i\\}_{i \\in I}) \\cdot (p \\cdot q; \\{k(S_k).H^t_k\\}_{k \\in K}) \\text{ for } J \\cup K = I \\text{ and, for } n, m = 1, 2, H^t_{nm} = \\\\\n\\text{where} & \\quad J \\cup K = I \\text{ and, for } n, m = 1, 2, H^t_{nm} = \\\\\n\\text{unm}\\_P^\\text{bin} & \\quad \\text{undefined otherwise}\n\\end{align*}\n\\]\n\nThe partial function projection-unmerge for localiser merge \\( \\text{unm}\\_P \\ L_L L_P \\) takes as input two lists of types instead of two pairs. It returns a tuple of lists: if \\( L_L = [H^t_1, \\ldots, H^n]\\) and \\( L_P = [H^t_1, \\ldots, H^m] \\) the result list is of the kind \\( ([H^t_1, H^t_2, H^t_1, H^t_2], \\ldots, [H^t_1, H^t_2, H^t_1, H^t_2]) \\) (\\( \\pi_I \\) indicate the standard projection\nof the $i$-th component of the tuple). $\\text{unmPL}$ is defined by recursion (on the sum of the lengths of $L_L$ and $L_P$) by the following equations.\n\n$$\\text{unmPL} \\; \\emptyset \\; L_P = (\\emptyset)$$\n$$\\text{unmPL} \\; [H^L] \\; L_P = ([L_P])$$\n\n$$\\text{unmPL} \\; [H^L_1, H^L_2] \\; L_P = \\begin{cases} \n([\\pi_1(\\text{unmPL}^{\\text{bin}} H^L_1), H^L_2], H^P) & \\text{if } L_P = [] \\\\\n([\\pi_1(\\text{unmPL}^{\\text{bin}} H^L_1, H^L_2), H^P]) & \\text{if } L_P = [H^P] \\\\\n([\\pi_1(\\text{unmPL}^{\\text{bin}} H^L_1, H^L_2), \\pi_2(\\text{unmPL}^{\\text{bin}} H^L_1, H^L_2)]) & \\text{if } L_P = [H^L_1, H^L_2] \\\\\n([\\pi_1(\\pi_1(U)) \\# L^1, \\pi_1(\\pi_2(U)) \\# L^2) & \\text{if } L_P = [H^L_1, H^L_2] \\\\\n\\end{cases}$$\n\n$$\\text{unmPL} \\; [H^L_1, H^L_2, \\ldots, H^L_n] \\; L_P = (L^1, \\pi_1(\\text{unmPL} \\; [(H^L_2, \\ldots, H^L_n) \\; L^2]), \\ldots, \\pi_{n-1}(\\text{unmPL} \\; [H^L_2, \\ldots, H^L_n] \\; L^2))$$\n\nwhere, for $i = 1, 2, L^i = \\text{unmPL} \\; [H^L_i, (\\bigcup_{k=2, \\ldots, n} H^L_k)] \\; L_L$\n\n**Lemma B.13.** We are given hybrid types $H^L_1, \\ldots, H^L_n$ and $H^P_1, \\ldots, H^P_m$ such that $\\bigcup_{i=1, \\ldots, n} H^L_i = \\bigcup_{j=1, \\ldots, m} H^P_j$.\n\nThen $\\text{unmPL} \\; [H^L_1, \\ldots, H^L_n] \\; [H^P_1, \\ldots, H^P_m]$ is defined and, if we set\n\n$$\\text{unmPL} \\; [H^L_1, \\ldots, H^L_n] \\; [H^P_1, \\ldots, H^P_m] = ([H^P_1, \\ldots, H^P_1], \\ldots, [H^P_n, \\ldots, H^P_n])$$\n\nwe have that:\n\n- $\\bigcup_{i=1, \\ldots, n} H^P_i = H^P_i$, for all $i = 1, \\ldots, n$, and\n- $\\bigcup^L_{i=1, \\ldots, n} H^P_i = H^P_i$, for all $j = 1, \\ldots, n$.\n\n**Proof.**\n\n- We first prove the base cases, in particular the case in which $n = 2$ and $m = 2$ (formally we first prove the result for $\\text{unmPL}^{\\text{bin}}$). This is done by structural induction on $H^L_1$, exploiting the hypothesis and the inductive nature both of $\\bigcup$ and $\\bigcup^L$.\n- We conclude by induction on $n + m$, by following the definition of $\\text{unmPL}$.\n\n**Definition B.14 (Unmerge for Projection).** The partial function binary unmerge for projection $\\text{unmP}^{\\text{bin}} H^E \\; H^P_1$ is defined by the following equations, by recursion on depth($H^E$), whenever the recursive call is\ndefined (we use $\\pi_1$ and $\\pi_2$ to indicate standard pair projections):\n\n\\[\n\\begin{align*}\n\\text{unmP}^{\\text{end}} (H_1^{tP} H_2^{tP}) &= (\\text{end}, \\text{end}) \\\\\n\\text{unmP}^{X} (H_1^{tP} H_2^{tP}) &= (X, X) \\\\\n\\text{unmP}^{(\\mu X. H^E)} (H_1^{tP} H_2^{tP}) &= \\begin{cases} \n(\\mu X.\\pi_1(\\text{unmP}^{H^E} H_1^{tP}, H_2^{tP}), \\mu X.\\pi_2(\\text{unmP}^{H^E} H_1^{tP}, H_2^{tP})) \\\\\n\\text{if } H_1^{tP} = \\mu X. H_1^{tP} \\text{ and } H_2^{tP} = \\mu X. H_2^{tP}, \\\\\n(\\mu X. H^E, \\mu X. H^E) \\text{ if } H_1^{tP} = H_2^{tP} = \\text{end}\n\\end{cases}\n\\end{align*}\n\\]\n\n\\[\n\\begin{align*}\n\\text{unmP}^{(H_1^{tP} H_2^{tP})} H_1^{tP} H_2^{tP} &= \\text{undefined} \\\\\n\\text{unmP}^{(p \\rightarrow q)} \\{ (f_i(S_i), H_1^{tP}) \\}_{i \\in I} H_1^{tP} H_2^{tP} &= \\\\\n&= \\begin{cases} \n(\\{ (f_j(S_j), H_{j}^{E_1}) \\}_{j \\in J}, \\text{p}' \\{ (f_k(S_k), H_{k}^{E_2}) \\}_{k \\in K}) & \\text{with } H_{j}^{E_1} = H_{j}^{E_2} \\text{ for } j \\in J \\cap K, \\\\\n&= \\pi_1(\\text{unmP}^{H^E} H_1^{tP} H_2^{tP}) \\text{ for } j \\in J \\cap K, \\\\\n&= \\pi_2(\\text{unmP}^{H^E} H_1^{tP} H_2^{tP}) \\text{ for } k \\in K \\cap J \\\\\n&\\text{if } H_{j}^{tP} = \\text{p}' \\{ (f_j(S_j), H_{j}^{E_1}) \\}_{j \\in J}, H_{j}^{tP} = \\text{p}' \\{ (f_k(S_k), H_{k}^{E_2}) \\}_{k \\in K} \\text{ and } J = J \\cup K\n\\end{cases} \\\\\n\\text{unmP}^{(p \\rightarrow q)} \\{ (f_i(S_i), H_1^{tP} H_2^{tP}) \\}_{i \\in I} H_1^{tP} H_2^{tP} &= \\\\\n&= \\begin{cases} \n(\\{ (f_j(S_j), \\pi_1(\\text{unmP}^{H^E} H_1^{tP} H_2^{tP})) \\}_{j \\in J}, \\text{p}' \\{ (f_k(S_k), \\pi_2(\\text{unmP}^{H^E} H_1^{tP} H_2^{tP})) \\}_{k \\in K}) & \\text{with unmP}^{\\text{loc}} [\\text{loc } H^E]_{i \\in I} [H_1^{tP}, H_2^{tP}] = (\\{ H_1^{tP}, H_2^{tP} \\})_{i \\in I}\n\\end{cases}\n\\end{align*}\n\\]\n\nThe partial function unmerge for projection unmP $H^E L$ is defined by the following equations, by recursion on the list of hybrid types $L$, whenever the recursive call is defined:\n\n\\[\n\\begin{align*}\n\\text{unmP}^{H^E [\\ ]} &= \\text{undefined} \\\\\n\\text{unmP}^{H^E [H_1^{tP}]} &= [H^E] \\\\\n\\text{unmP}^{H^E [H_1^{tP}, H_2^{tP}]} &= [\\pi_1(\\text{unmP}^{H^E} H_1^{tP} H_2^{tP}), \\pi_2(\\text{unmP}^{H^E} H_1^{tP} H_2^{tP})] \\\\\n\\text{unmP}^{H^E [H_1^{tP}, \\#(H_2^{tP} \\#L)]} &= \\pi_1(\\text{unmP}^{H^E} H_{1}^{tP} (\\bigcup (\\text{set}(H_2^{tP} \\#L))) \\# \\text{unmP} \\pi_2(\\text{unmP}^{H^E} H_1^{tP} (\\bigcup (\\text{set}(H_2^{tP} \\#L))) (H_2^{tP} \\#L))\n\\end{align*}\n\\]\n\n**Lemma B.15 (Unmerge for Projection).** We fix a set of participants $E$, and we are given hybrid types $H_{1}^{tP}, \\ldots, H_{n}^{tP}$ such that:\n\n(a) $\\text{ipart}(H^E) \\subseteq E$, for all $t = n$,\n(b) $\\text{epar}(H^E) \\cap E = \\emptyset$,\n(c) $\\text{loc } H^E = \\bigcup_{t=1, \\ldots, n} H_{t}^{tP}$\n\nthen, for all $t = 1, \\ldots, n$, we call $H_{t}^{tP}$ the $t$-th element of the list unmP\\textsubscript{E} $H^E [H_{1}^{tP}, \\ldots, H_{n}^{tP}]$ and we have\n\n\\[\n\\begin{align*}\n(1) \\text{loc } H_{t}^{tP} = H_{t}^{tP}, \\text{ for all } t = 1, \\ldots, n \\text{ and} \\\\\n(2) \\bigcup_{t \\in T} H_{t}^{tP} = H^E.\n\\end{align*}\n\\]\n\n**Proof.** As for Lemma B.11, the proof is pretty technical: we first prove the binary case $n = 2$—which goes by induction on the depth($H^E$) and needs lemma B.13—and then we generalise it to any $n$ by induction. The proof is totally analogous to the proof of Lemma B.11, with the difference that localiser and projection “play inverted roles”. \\qed\nWe give an algorithm to explicitly build “back” a hybrid type, from two compatible types $H^\\uparrow$ and $H^E$. We first describe the algorithm as a (partial) recursive function in the next Definition B.16, then, with Theorem B.17, we prove that such functions has the desired behaviour.\n\n**Definition B.16 (Build-Back of a Single Component).** Given a set of participants $E$, the build-back of a single component is the partial recursive function $B_E^1 H^\\uparrow H^E$ defined below, by recursion on $\\text{depth}(H^\\uparrow) + \\text{depth}(H^E)$. (In what follows we indicate by $\\pi_i$ the function that given a list returns its $i$-th element, when it exists.)\n\nIf $\\text{ipart}(H^E) \\not\\in E$, $B_E^1 H^\\uparrow H^E$ is undefined, otherwise it is defined by the following equations:\n\n- $B_E^1 \\text{end} H^E = H^E$\n- $B_E^1 X H^E = H^E$\n- $B_E^1 (\\mu X. H^\\uparrow) H^E = \\begin{cases} \\{ (\\mu X. H^\\uparrow) | H^E \\text{ if } \\text{ipart}(H^\\uparrow) \\cap E = \\emptyset \\text{ and both } \\mu X. H^\\uparrow \\text{ and } H^E \\text{ are closed} \\\\ s \\to r : (t(S). (B_E^1 (\\mu X. H^\\uparrow) H^E))_{i \\in I} \\text{ if } \\text{ipart}(H^\\uparrow) \\cap E = \\emptyset, H^E = s \\to r : \\{ t(S). H^E \\}_{i \\in I}, \\text{ and one of } \\mu X. H^\\uparrow \\text{ and } H^E \\text{ is not closed} \\\\ \\mu X. (B_E^1 H^\\uparrow H^E') \\text{ if } \\text{ipart}(H^\\uparrow) \\cap E \\neq \\emptyset \\text{ and } H^E = \\mu X. H^E' \\\\ \\end{cases}$\n- $B_E^1 (H^1_1 H^1_2) H^E = \\begin{cases} (B_E^1 H^1_1 H^E) | H^1_2 \\text{ if } \\text{ipart}(H^1_1) \\cap E = \\emptyset \\\\ H^1_2 \\mid (B_E^1 H^1_1 H^E) \\text{ if } \\text{ipart}(H^1_1) \\cap E \\neq \\emptyset \\text{ and } \\text{ipart}(H^1_2) \\cap E = \\emptyset \\\\ \\end{cases}$\n- $B_E^1 p \\langle q; \\{ t(S_i). H^E \\}_{i \\in I} \\rangle | H^E = \\begin{cases} p \\langle q; \\{ t(S_i). (B_E^1 H^1_1 H^E) \\}_{i \\in I} \\rangle \\text{ if } H^E = p \\langle q; \\{ t(S_i). H^E \\}_{i \\in I} \\rangle \\text{ and } p \\in E \\\\ s \\to r : (m_j(S_j). (B_E^1 H^1_1 \\text{ UP} \\}_{j \\in J} \\text{ if } H^E = s \\to r : \\{ m_j(S_j). H^E \\}_{j \\in J} \\text{ and } q \\in E \\\\ p \\langle q; \\{ t(S_i). (B_E^1 H^1_1 \\text{ UP} \\}_{j \\in J} \\text{ if } H^E = p \\langle q; \\{ t(S_i). H^E \\}_{j \\in J} \\rangle \\text{ and } q \\in E \\\\ \\end{cases}$\n- $B_E^1 p \\langle q; \\{ t(S_i). H^E \\}_{i \\in I} \\rangle | H^E = \\begin{cases} p \\langle q; \\{ t(S_i). (B_E^1 H^1_1 H^E) \\}_{i \\in I} \\rangle \\text{ if } H^E = p \\langle q; \\{ t(S_i). H^E \\}_{i \\in I} \\rangle \\text{ or } H^E = p \\langle q; \\{ t(S_i). H^E \\}_{i \\in I} \\rangle \\text{ and } p \\in E \\text{ or } q \\in E \\\\ s \\to r : (m_j(S_j). (B_E^1 H^1_1 \\text{ UP} \\}_{j \\in J} \\text{ if } H^E = s \\to r : \\{ m_j(S_j). H^E \\}_{j \\in J} \\text{ and } p \\in E \\text{ or } q \\in E \\\\ p \\langle q; \\{ t(S_i). (B_E^1 H^1_1 \\text{ UP} \\}_{j \\in J} \\text{ if } H^E = p \\langle q; \\{ t(S_i). H^E \\}_{j \\in J} \\rangle \\text{ and } p \\in E \\text{ or } q \\in E \\\\ \\end{cases}$\n\nand undefined if none of the above applies.\n\nWe observe that, in the above definition, for $H^\\uparrow = p \\to q : \\ldots$, we have left undefined the case in which $\\{ p, q \\} \\subseteq E$. That is because $E$ is the set of participants for a certain component and the messages $p \\to q : \\ldots$ are for internal communication within this component. Namely such messages belong to $H^E$, not to $H^\\uparrow$, which instead is the type for inter-component communication.\n\nFinally, we prove the technical result that supports our whole theory. This theorem allows us to compose two hybrid types—$H^\\uparrow$, disciplining the inter-component communication of the system,\nand $H^E$, taking care of interactions within a single component—into all the information of the two, in terms of projections. The proof of this theorem relies on the just-proved lemmas and goes by a combination of induction on the depth of both given types $H^+$ and $H^E$, and of case analysis on these.\n\n**Theorem B.17 (Building Back a Single Component).**\nWe fix a set of participants $E$, and we are given hybrid types $H^+$ and $H^E$, such that:\n\n1. $\\text{ipart}(H^E) \\subseteq E$,\n2. $\\text{epart}(H^E) \\cap E = \\emptyset$, and\n3. $H^+ \\upharpoonright_E = \\text{loc } H^E$;\n\nwe set $H = \\mathcal{B}_E^1 H^+ H^E$ and we have:\n\n1. $H \\upharpoonright_E = H^E$ and\n2. for all $E'$, such that $E' \\cap E = \\emptyset$, $H \\upharpoonright_{E'} = H^+ \\upharpoonright_{E'}$.\n\nMoreover if isGlobal($H^+$) then isGlobal($H$).\n\n**Proof.** By induction on $d = \\text{depth}(H^+)$ + $\\text{depth}(H^E)$. The case $d = 0$ is trivial; let us then have $d = n + 1$ and assume the theorem true for all $H'^+$, $H'$ as in hypothesis, for which $\\text{depth}(H'^+) + \\text{depth}(H') \\leq n$. We proceed by case analysis on $H^+$.\n\n$[H^+ = \\text{end}]$ By definition $H = H^E$; we observe that 1. projection onto a set containing all the internal participants is the identity function (Lemma B.4), and 2. projection of a closed type ($H^E$ is closed since its localisation is, Lemma B.3), onto a set of roles disjoint from the internal participants, is end (Lemma B.5).\n\n$[H^+ = X]$ We observe that, since $\\text{loc } H^E = X$, either $H^E = X$, for which our proof is trivial, or $H^E = s \\rightarrow r : \\{\\ell_i(S_i).H^E_i\\}_{i \\in I}$, in which case we observe that $X = \\bigcup_{i \\in I} \\text{loc } H^E_i = \\text{loc } H^E_i$. By induction on $\\text{depth}(H^E)$ we prove our result.\n\n$[H^+ = \\mu X.H'^+]$ All cases go by induction hypothesis, but the second case, where $H^+$ and $H^E$ share some participant, but they are not both closed. In fact, both are not for condition (c). Thanks to condition (c), Lemma B.5, and a similar argument to the one used in the $[H^+ = X]$ case above, we conclude by induction hypothesis.\n\n$[H^+ = H^+_1.H^+_2]$ We observe that $H^+ \\upharpoonright_E = H^+_1 \\upharpoonright_E$, (or $H^+ \\upharpoonright_E = H^+_2 \\upharpoonright_E$) without loss of generality. We conclude by induction hypothesis.\n\n$[H^+ = p!q; \\{\\ell_i(S_i).H^+_i\\}_{i \\in I}]$\n\n1. If $p \\in E$ and $H^E = p!q; \\{\\ell_i(S_i).H^+_i\\}_{i \\in I}$ we conclude by construction of $H = \\mathcal{B}_E^1 H^+ H^E$ and induction hypothesis.\n2. If $p \\in E$ and $H^E = r \\rightarrow s : \\{m_j(S'_j).H^E_j\\}_{j \\in J}$, then $p!q;\\{\\ell_i(S_i).(H^+_i \\upharpoonright_E)\\} = \\bigcup_{j \\in J} \\text{loc } H^E_j$. We can therefore apply Lemma B.11 and obtain that for $\\text{UL}_j = \\pi_j(\\text{unmL } H^+ \\upharpoonright [\\text{loc } H^E_j]_{j \\in J})$ we have $\\text{loc } H^+_j = \\text{UL}_j \\upharpoonright_E$ (for all $j \\in J$) and $\\bigcup_{j \\in J} \\text{UL}_j \\upharpoonright_{E'} = H^+ \\upharpoonright_{E'}$ (for all $E' \\cap E = \\emptyset$). By construction (namely $\\mathcal{B}_E^1 H^+ H^E = s!r;\\{m_j(S'_j).\\{\\mathcal{B}_E^1 H^+_i \\text{UL}_j H^E_j\\}_{j \\in J}\\}$ and induction hypothesis we conclude.\n3. If $p \\notin E$, we have that $\\text{loc } H^E = \\bigcup_{i \\in I} \\{H^+_i \\upharpoonright_E\\}$. We apply Lemma B.15 and, for $\\text{UP}_i = \\pi_i(\\text{unmP } H^+ [H^+_i \\upharpoonright_E]_{i \\in I})$, we have $\\text{loc } \\text{UP}_i = (H^+_i \\upharpoonright_E)$ and $\\bigcup_{i \\in I} \\text{UP}_i = H^E$. By construction (namely $\\mathcal{B}_E^1 H^+ H^E = p!q;\\{\\ell_i(S_i).\\{\\mathcal{B}_E^1 H^+_i \\text{UP}_i\\}_{i \\in I}\\}$) and induction hypothesis we conclude.\n\\[ H^* = p?q; \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\text{ and } H^* = p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\] These are analogous to to the above \"send\" case: in essence, they follow the different cases of the Definition 4.1 of \\( B_E \\) which are similar for all three different kind of messages.\n\n\\[ \\square \\]\n\n### B.2 Projection for Hybrid Types and Set Inclusion\n\nThe following lemma is needed for proving preservation of projection (Theorem B.19 below), which is essential for achieving distributed specification for communication protocols.\n\n**Lemma B.18 (Projection Distributes over Merge).** Given \\( H = \\bigsqcup_{i=1, \\ldots, n} H_i \\), then \\( H \\upharpoonleft E = \\bigsqcup_{n=1, \\ldots, N} H_i \\upharpoonleft E \\)\n\n**Proof.** Let us first prove the lemma for \\( n = 2 \\): \\( H = H_1 \\sqcup H_2 \\). We proceed by induction on \\( H \\).\n\nCases \\( H = \\text{end} \\) and \\( H = X \\) are trivial.\n\nLet us consider \\( H = \\mu X.H' \\), then \\( H_1 = \\mu X.H_1' \\) and \\( H_2 = \\mu X.H_2' \\), with \\( H' = H_1' \\sqcup H_2' \\). If \\( H \\) is closed and \\( \\mu X.H' \\upharpoonleft E \\) is not guarded, than neither are \\( \\mu X.H_1' \\upharpoonleft E \\) and \\( \\mu X.H_2' \\upharpoonleft E \\) (by reasoning on the participants of the result of \\( \\sqcup \\) and the well-formedness of initial types), thus we conclude. In the other case, the thesis follows by induction hypothesis.\n\nIf \\( H = H_a | H_b \\) the thesis follow simply by applying induction hypothesis.\n\nLet us consider the send case \\( H = p!q; \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\), and hence \\( H_1 = p!q; \\{\\ell_i(S_i).H_{1i}\\}_{i \\in I} \\) and \\( H_2 = p!q; \\{\\ell_i(S_i).H_{2i}\\}_{i \\in I} \\). If \\( p \\in E \\) then we conclude by definition of merge and induction hypothesis. If \\( p \\notin E \\), then\n\n\\[\nH \\upharpoonleft E = \\bigsqcup_{i \\in I} (H_1 \\upharpoonleft E | H_2 \\upharpoonleft E) \\]\n\nWe have marked with \\( \\upharpoonleft H \\) where we have exploited the induction hypothesis; all the other equalities follow by definitions or by associativity and commutativity of merge.\n\nIf \\( H = p?q; \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\), we have \\( H_1 = p?q; \\{\\ell_i(S_i).H_{1i}\\}_{i \\in I} \\) and \\( H_2 = p?q; \\{\\ell_k(S_k).H_{2k}\\}_{k \\in K} \\).\n\nSince, \\( H = H_1 \\sqcup H_2 \\), we observe that:\n\n- if \\( i \\in J \\setminus K \\) then \\( H_i = H_i^1 \\),\n- if \\( i \\in K \\setminus J \\) then \\( H_i = H_i^2 \\), and\n- if \\( i \\in J \\cap K \\) then \\( H_i = H_i^1 \\sqcup H_i^2 \\).\n\nIf \\( q \\in E \\) we conclude by applying the definition of projection to \\( H = p?q; \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\) and induction hypothesis when \\( i \\in J \\cap K \\). If \\( q \\notin E \\) we have\n\n\\[\nH \\upharpoonleft E = \\bigsqcup_{i \\in I} H_i \\upharpoonleft E = (\\bigsqcup_{i \\in J \\setminus K} H_i^1 \\upharpoonleft E) \\sqcup (\\bigsqcup_{i \\in J \\setminus K} H_i^2 \\upharpoonleft E) = (\\bigsqcup_{i \\in J \\setminus K} H_i^1 \\upharpoonleft E) \\sqcup (\\bigsqcup_{i \\in J \\setminus K} H_i^2 \\upharpoonleft E) \\]\n\nAs above induction hypothesis, definition, and associativity and commutativity of merge.\n\nThe case \\( H = p \\rightarrow q : \\{\\ell_i(S_i).H_i\\}_{i \\in I} \\) has four cases:\n\n- \\( \\{p, q\\} \\subseteq E \\), analogous to the send case above \\( p!q; \\ldots \\), when \\( p \\in E \\).\n\\begin{itemize}\n\\item $p \\in E$ and $q \\notin E$, analogous to the send case above $p!q; \\ldots$, when $pinE$.\n\\item $p \\notin E$ and $q \\in E$, analogous to the receive case above $p?q; \\ldots$, when $qinE$.\n\\item $\\{p, q\\} \\cap E = \\emptyset$, analogous to the send case above $p!q; \\ldots$, when $p \\notin E$.\n\\end{itemize}\n\nNow, to have the full lemma for $t = 1, \\ldots, n$, for a generic $n$, it is sufficient to proceed by induction on $n$: we observe that $H = \\bigcup_{t=1, \\ldots, n} H_t = (\\bigcup_{t=1, \\ldots, n-1} H_t) \\cup H_n$. Now, thanks to the case $n = 2$ above, we have $H \\upharpoonright E = ((\\bigcup_{t=1, \\ldots, n-1} H_t) \\cup H_n) \\upharpoonright E = (\\bigcup_{t=1, \\ldots, n-1} H_t) \\upharpoonright E \\cup H_n \\upharpoonright E$. Since, by induction hypothesis $(\\bigcup_{t=1, \\ldots, n-1} H_t) \\upharpoonright E = \\bigcup_{t=1, \\ldots, n-1} H_t \\upharpoonright E$, we conclude.\n\n\\hfill $\\square$\n\nThe following theorem proves that generalised projection on hybrid types is sound with respect to set inclusion. This is the conclusive step of our theory: after composing subprotocols into a general global type, thanks to the theorem below, we are guaranteed that, by projecting a hybrid type for some subprotocol onto one of its participant, we obtain the same local type as we would if we projected directly from the global type that we have obtained by composition, and that disciplines the whole communication.\n\n\\textbf{Theorem B.19 (Projection Composes over Set Inclusion).} Given $H$, $E_1$ and $E_2$, with $E_2 \\subseteq E_1$, assuming $(H \\upharpoonright E_1) \\upharpoonright E_2$ is defined, $(H \\upharpoonright E_1) \\upharpoonright E_2 = H \\upharpoonright E_2$\n\n\\textbf{Proof of Theorem 4.9.} By induction on $H$.\n\n\\begin{itemize}\n\\item $[H = \\text{end}]$ and $[H = X]$ are immediate.\n\\item $[H = \\mu X.H']$ We observe that, if $\\mu X.H' \\upharpoonright E_1$ is not guarded, then neither is $\\mu X.H' \\upharpoonright E_2$, since $E_2 \\subseteq E_1$ (this result is obtained simply by structural induction over $H$). Also, we know that the property of being closed is preserved by projection. In case $\\mu X.H' \\upharpoonright E_1$ is guarded, but $\\mu X.H' \\upharpoonright E_2$ is not, then (since $H' \\upharpoonright E_1$ is guarded, by Lemma B.7) we have that $\\text{ipart}(H') \\cap E_2 = \\emptyset$ and hence also $\\text{ipart}((H' \\upharpoonright E_1)) \\cap E_2 = \\emptyset$ (ipart($H \\upharpoonright E_2$)) $\\subseteq$ ipart($H$); by structural induction on $H$. We can then conclude by following the defining rule for projection, in the recursion case ([\\text{PROJ-REC}] in Definition 3.6), and by applying induction hypothesis and Lemma B.5 (depending on the cases).\n\\item $[H = H_1|H_2]$ Since projections are defined, w.l.o.g., we can assume $E_2 \\subseteq E_1 \\subseteq \\text{ipart}(H_1)$. We conclude by direct application of induction hypothesis on $H_1$.\n\\item $[H = \\text{sl}ext; \\{\\ell_i(S_i).H_i\\}_{i \\in I}]$ We observe that ext $\\notin E_1$.\n\\begin{itemize}\n\\item \\textbf{(a)} If $s \\notin E_1$, then $(H \\upharpoonright E_1) \\upharpoonright E_2 = \\bigcup_{i \\in I} (H_i \\upharpoonright E_2)$; by applying Lemma B.18 and induction hypothesis we have $(H \\upharpoonright E_1) \\upharpoonright E_2 = \\bigcup_{i \\in I} (H_i \\upharpoonright E_2)$ which is exactly what we need (since $s \\notin E_1$ entails $s \\notin E_2$).\n\\item \\textbf{(b)} If $s \\in E_1 \\setminus E_2$, then $H \\upharpoonright E_1 = \\text{sl}ext;\\{\\ell_i(S_i).(H_i \\upharpoonright E_2)\\}_{i \\in I}$. By induction hypothesis, we then have $(H \\upharpoonright E_1) \\upharpoonright E_2 = \\bigcup_{i \\in I} (H_i \\upharpoonright E_2) \\upharpoonright E_2 = \\bigcup_{i \\in I} H_i \\upharpoonright E_2$ and we conclude.\n\\item \\textbf{(c)} If $s \\in E_2$, no merge happens and we conclude by simply unfolding the definition of projection and applying induction hypothesis.\n\\end{itemize}\n\\item $[H = \\text{sr}ext; \\{\\ell_i(S_i).H_i\\}_{i \\in I}]$ Analogous to the previous “send” case.\n\\end{itemize}\n\\[H = s \\rightarrow r : \\{\\ell_i(S_i), H_i\\}_{i \\in I}\\]\n\n(a) If \\(s, r \\notin E_1\\), then \\((H \\upharpoonright E_1) \\upharpoonright E_2 = \\bigcup_{i \\in I} (H_i \\upharpoonright E_1) \\upharpoonright E_2\\) and \\(H \\upharpoonright E_2 = \\bigcup_{i \\in I} H_i \\upharpoonright E_2\\). We conclude analogously to (a) in case \\([H = s!ext; \\{\\ell_i(S_i), H_i\\}_{i \\in I}]\\) above, by applying Lemma B.18 and induction hypothesis.\n\n(b) If \\(1. s, r \\in E_1 \\setminus E_2, 2. s \\in E_1 \\setminus E_2\\) and \\(r \\notin E_1\\), or 3. \\(r \\in E_1 \\setminus E_2\\) and \\(s \\notin E_1\\), then we have, respectively:\n\n\\[\n\\begin{align*}\n1. H \\upharpoonright E_1 &= s \\rightarrow r : \\{\\ell_i(S_i), (H_i \\upharpoonright E_1)\\}_{i \\in I}, \\\\\n2. H \\upharpoonright E_1 &= s!r; \\{\\ell_i(S_i), (H_i \\upharpoonright E_1)\\}_{i \\in I}, \\text{ or} \\\\\n3. H \\upharpoonright E_1 &= s?r; \\{\\ell_i(S_i), (H_i \\upharpoonright E_1)\\}_{i \\in I}.\n\\end{align*}\n\\]\n\nIn all cases, we conclude analogously to (b) in case \\([H = s!ext; \\{\\ell_i(S_i), H_i\\}_{i \\in I}]\\) above.\n\n(c) If \\(1. s \\in E_2\\) and \\(r \\notin E_1\\), or 2. \\(r \\in E_2\\) and \\(s \\notin E_1\\), then we have, respectively:\n\n\\[\n\\begin{align*}\n1. H \\upharpoonright E_1 &= s!r; \\{\\ell_i(S_i), (H_i \\upharpoonright E_1)\\}_{i \\in I}, \\text{ or} \\\\\n2. H \\upharpoonright E_1 &= s?r; \\{\\ell_i(S_i), (H_i \\upharpoonright E_1)\\}_{i \\in I}.\n\\end{align*}\n\\]\n\nIn both cases, we conclude analogously to (c) in case \\([H = s!ext; \\{\\ell_i(S_i), H_i\\}_{i \\in I}]\\) above.\n\n(d) If \\(1. s \\in E_2\\) and \\(r \\in E_1 \\setminus E_2\\), or 2. \\(r \\in E_2\\) and \\(s \\in E_1 \\setminus E_2\\), then we have, in both cases, \\(H \\upharpoonright E_1 = s \\rightarrow r : \\{\\ell_i(S_i), (H_i \\upharpoonright E_1)\\}_{i \\in I}\\). Then, projecting on \\(E_2\\), respectively:\n\n\\[\n\\begin{align*}\n1. (H \\upharpoonright E_1) \\upharpoonright E_2 &= s!r; \\{\\ell_i(S_i), (H_i \\upharpoonright E_1)\\}_{i \\in I}, \\text{ or} \\\\\n2. (H \\upharpoonright E_1) \\upharpoonright E_2 &= s?r; \\{\\ell_i(S_i), (H_i \\upharpoonright E_1)\\}_{i \\in I}.\n\\end{align*}\n\\]\n\nIn both cases, we conclude by induction hypothesis.\n\n(e) If \\(s, r \\in E_2\\) then we have: \\(H \\upharpoonright E_1 = s \\rightarrow r : \\{\\ell_i(S_i), (H_i \\upharpoonright E_1)\\}_{i \\in I}\\). Then, \\((H \\upharpoonright E_1) \\upharpoonright E_2 = s \\rightarrow r : \\{\\ell_i(S_i), ((H_i \\upharpoonright E_1) \\upharpoonright E_2)\\}_{i \\in I}\\). We conclude by induction hypothesis.\n\n\\[\\square\\]\n\n### B.3 Projection and Localiser for Hybrid Types with Delegation\n\nWe define here projection and localiser for our extension of hybrid types to delegation and explicit connections, from §5.4.\n\n**Definition B.20 (Projection for Hybrid Types with Delegation).** The projection on the set of participants \\(E\\) for hybrid types with delegation, is a partial operator, recursively defined by the clauses in Figure 10 (whenever the recursive call is defined).\n\n*Merging* \\((\\sqcup)\\) is defined as a partial commutative operator over two hybrid types such that: for all \\(H, H' \\sqcup H = H\\), it delves inductively inside all constructors (see Definition 3.6), and\n\n\\[\n(\\bigwedge_{i \\in I} P_i ?^* q_i (\\ell_i); H_i) \\sqcup (P \\sqcap q (\\ell); H) = (\\bigwedge_{i \\in I} P_i ?^* q_i (\\ell_i); H_i) \\lor (P \\sqcap q (\\ell); H)\n\\]\n\nif the resulting intersection is non-ambiguous\n\n\\[\n(\\bigwedge_{i \\in I} P_i ?^* q_i (\\ell_i); H_i) \\sqcup (P \\sqcap q (\\ell); H) = (\\bigwedge_{i \\in I} P_i ?^* q_i (\\ell_i); (H_i \\sqcup H))\n\\]\n\nif \\(p = p_i, q = q_i, \\text{and } \\ell = \\ell_i\\) for some \\(i \\in I\\)\n\n\\[\n(\\bigwedge_{i \\in I} P_i ?^r q_i (\\ell_i); H_i) \\sqcup \\text{End} = (\\bigwedge_{i \\in I} P_i ?^r q_i (\\ell_i); H_i)\n\\]\n\nWe use an inductive version of merge, which is more restrictive than (and hence compatible with) the equirecursive merge in [Castellani et al. 2020], Definition 4.8 and following discussion. An input intersection \\(\\bigwedge_{i \\in I} P_i ?^r q_i (\\ell_i); H_i\\) is *non-ambiguous* if all inputs are distinct and if \\(q \\neq r\\), whenever the intersection combines a simple input \\(P ? q\\) and connecting input \\(s ?^r r\\).\n\nThe partial function \\(\\frac{\\frac{d}{dE}}{d}\\) (defined by the rules below) generalises the delegation projection functions \\(\\frac{\\frac{\\downarrow}{\\downarrow} (p,q)}{\\downarrow} \\) and \\(\\frac{\\frac{\\downarrow}{\\downarrow} (p,q)}{\\downarrow}\\) from [Castellani et al. 2020] (Figure 6): as in that paper, this function is of a sequentical nature: it is not defined for branching, recursion, and parallel constructs. In Figure 11, we provide the full definition. To obtain well-delegated hybrid types (see Definition 4.11 in [Castellani et al. 2020]) and correctly nest delegation, we have added the set argument \\(dE\\), that keeps track of the delegation pairs. We ask that, if \\(\\{ (p, q) \\}, (s, r) \\subseteq dE\\), then \\(\\{ (p, q) \\} \\cap \\{ (s, r) \\} = \\emptyset\\).\nWe can use one function \\( \\Uparrow \\), for generalising both \\( \\PDownarrow (.) \\) and \\( \\PDownarrow (.) \\), since we rely on the set \\( E \\), namely:\n- \\( \\chi \\Downarrow 1 (p,q) \\) is generalised by \\( \\chi \\Downarrow d (p,q), E \\), when \\( p \\in E \\) and \\( q \\notin E \\), while \\( \\chi \\Downarrow 2 (p,q) \\) is generalised by \\( \\chi \\Downarrow d ( (p,q), E ) \\) when \\( q \\in E \\) and \\( p \\notin E \\).\n\nIn Figure 11, we use the following notation:\n- \\( \\mathcal{H} \\Downarrow 0, E \\), for the projection extended to prefixes \\( \\mathcal{H} \\), in the obvious way;\n- \\( \\mathcal{H} \\Downarrow \\emptyset, E \\), for \\( \\mathcal{H} \\Downarrow \\emptyset \\); and\n- \\( \\text{disj}_p \\Downarrow (p, q) dE \\) when the following holds: for all \\( (s, r) \\in dE \\), \\( \\{p, q\\} \\cap \\{s, r\\} = \\emptyset \\).\n\nThe intuition behind these rules is the following: whenever a forward delegation is encountered while projecting, the control is passed to \\( \\Uparrow \\), e.g., \\( p \\circ \\langle \\bullet q \\rangle ; \\mathcal{H} \\Downarrow E = p \\circ \\langle \\bullet [q] ; H \\rangle \\Downarrow d ( (p, q), E ) \\) if \\( p \\in E \\), which takes care of projecting the sequence (single branch) in \\( H \\) of elementary interactions (messages or well-nested delegations, see [Castellani et al. 2020], Definition 4.11), until a dual backward delegation \\( q \\circ \\rangle \\rangle p ; H' \\) is encountered and the control is passed back to \\( \\Downarrow \\), e.g., \\( q \\circ \\rangle \\rangle p ; H' \\Downarrow d ( (p, q), E ) = [q] \\bullet \\rangle \\rangle p ; H' \\Downarrow E \\).\n\n**Definition B.21 (Localiser for Hybrid Types with Delegation).** The localiser for hybrid types with delegation, is a partial operator, recursively defined by the clauses in Figure 12 (whenever the recursive call is defined).\n\n**Merging for the localiser** (\\( \\sqcup \\)) is defined as a partial commutative operator over two hybrid types such that: for all \\( H, H' \\sqcup H = H' \\), it delves inductively inside all constructors (see Definition 3.8), and\n\n\\[\n\\begin{align*}\n\\left( \\bigoplus_{i \\in I} p^! q_i (\\ell_i) ; H_i \\right) \\sqcup (p^! q (\\ell) ; H) & = \\left( \\bigoplus_{i \\in I} p^! q_i (\\ell_i) ; H_i \\right) \\sqcup (p^! q (\\ell) ; H) \\\\\n\\left( \\bigoplus_{i \\in I} p^! q_i (\\ell_i) ; H_i \\right) \\sqcup (p^! q (\\ell) ; H) & = \\left( \\bigoplus_{i \\in I} p^! q_i (\\ell_i) ; (H_i \\sqcup H) \\right) \\\\\n(\\bigoplus_{i \\in I} p^! q_i (\\ell_i) ; H_i) \\sqcup \\text{end} & = (\\bigoplus_{i \\in I} p^! r q_i (\\ell_i) ; H_i)\n\\end{align*}\n\\]\n\nif \\( p = p_i \\), \\( q = q_i \\), and \\( \\ell = \\ell_i \\), for some \\( i \\in I \\).\nFig. 10. Recursive Rules for Projection for Hybrid Types with Delegation\nIf $p \\in E$, $q \\notin E$, and $(p, q) \\in dE$, $\\sigma(f); H|^{d}_{dE} = \\begin{cases} H|^{d}_{dE} & \\text{if } \\text{ipart}(\\sigma) \\cap (\\{q\\} \\cup E) \\subseteq \\{p\\} \\\\ (\\sigma|_{E\\setminus\\{p\\}})(f); (H|^{d}_{dE}) & \\text{if } \\text{ipart}(\\sigma) \\subseteq E \\setminus \\{p\\} \\end{cases}$\n\nIf $p \\notin E$, $q \\in E$, and $(p, q) \\in dE$,\n$(s \\rightarrow * r(f); H)|^{d}_{dE} = \\begin{cases} q \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } p = s, q \\neq r, \\text{and } r \\in E \\\\ s \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } p = r, q \\neq s, \\text{and } s \\in E \\\\ q \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } p = s, q \\neq r, \\text{and } r \\notin E \\\\ s \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } p = r, q \\neq s, \\text{and } s \\notin E \\end{cases}$\n\nIf $p \\notin E$, $q \\in E$, and $(p, q) \\in dE$,\n$(s' \\rightarrow * r(f); H)|^{d}_{dE} = \\begin{cases} q \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } p = s, q \\neq r, \\text{and } r \\notin E \\\\ s' \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } s, r \\subseteq E \\end{cases}$\n\nIf $p \\notin E$, $q \\in E$, and $(p, q) \\in dE$,\n$(s' \\rightarrow * r(f); H)|^{d}_{dE} = \\begin{cases} q \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } p = s, q \\neq r, \\text{and } r \\notin E \\\\ s' \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } s, r \\subseteq E \\end{cases}$\n\nIf $p \\notin E$, $q \\in E$, and $(p, q) \\in dE$,\n$(s' \\rightarrow * r(f); H)|^{d}_{dE} = \\begin{cases} q \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } p = s, q \\neq r, \\text{and } r \\notin E \\\\ s' \\rightarrow * r(f); (H|^{d}_{dE}) & \\text{if } s, r \\subseteq E \\end{cases}$\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(p \\circ (\\bullet; q); H)|^{d}_{dE} = \\begin{cases} p \\circ (\\bullet; q); (H|^{d}_{dE}) & \\text{if } p \\in E \\text{ and } q \\notin E \\\\ q \\circ (\\bullet; p); (H|^{d}_{dE}) & \\text{if } p \\notin E \\text{ and } q \\in E \\text{ and } (p, q) \\in dE \\end{cases}$\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(q \\circ (\\bullet; p); H)|^{d}_{dE} = \\begin{cases} p \\circ (\\bullet; q); (H|^{d}_{dE}) & \\text{if } p \\in E \\text{ and } q \\notin E \\\\ q \\circ (\\bullet; p); (H|^{d}_{dE}) & \\text{if } p \\notin E \\text{ and } q \\in E \\text{ and } (p, q) \\in dE \\end{cases}$\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nIf $\\text{disj\\_pair}(p, q) \\in dE$, $(\\text{disj\\_pair}(p, q); dE = \\emptyset \\subseteq E$.\n\nFig. 11. Delegation Projection for Hybrid Types with Delegation.\n\nEquations for $\\text{loc\\_end}$, $\\text{loc\\_X}$, $\\mu X.H$, and $H_1|H_2$ are the same as in Definition 3.8.\n\n\\begin{align*}\n\\text{loc\\_MSG} & \\quad \\text{loc\\_SEND} & \\quad \\text{loc\\_FUN} \\\\\n\\text{loc\\_BD} & \\quad \\text{loc\\_APD} & \\quad \\text{loc\\_ARR} \\\\\n\\text{loc\\_PFS} & \\quad \\text{loc\\_APR} & \\quad \\text{loc\\_PPr} \\\\\n\\text{loc\\_INT} & \\quad \\text{loc\\_CHIEF} \\\\\n\\text{loc\\_INTER} & \\quad \\text{loc\\_MODE}\n\\end{align*}\n\nFig. 12. Recursive Rules for the Localiser for Hybrid Types with Delegation."}}},{"rowIdx":61,"cells":{"id":{"kind":"string","value":"e2a718221a114d12d8e6e2495b0af0e01f137d2b"},"text":{"kind":"string","value":"CA Top Secret® r14 SP1 for z/OS\nSecurity Target\n\nVersion 1.1\nMarch 7, 2011\n\nPrepared for:\nCA\n2400 Cabot Drive\nLisle, IL 60532\n\nPrepared by:\nBooz Allen Hamilton\nCommon Criteria Testing Laboratory\n900 Elkridge Landing Road, Suite 100\nLinthicum, MD 21090-2950\nTable of Contents\n\n1 Security Target Introduction ................................................................. 8\n1.1 ST Reference .................................................................................. 8\n1.1.1 ST Identification ................................................................. 8\n1.1.2 Document Organization ......................................................... 8\n1.1.3 Terminology ........................................................................... 9\n1.1.4 Acronyms .............................................................................. 12\n1.1.5 References ............................................................................. 13\n1.1.6 CC Concepts .......................................................................... 14\n1.2 TOE Reference ............................................................................. 14\n1.2.1 TOE Identification ............................................................... 14\n1.3 TOE Overview ............................................................................. 14\n1.4 TOE Type ..................................................................................... 17\n2 TOE Description .............................................................................. 18\n2.1 Evaluated Components of the TOE ............................................. 18\n2.2 Components and Applications in the Operational Environment .. 20\n2.3 Excluded from the TOE ............................................................... 21\n2.3.1 Not Installed ........................................................................ 21\n2.3.2 Installed but Requires a Separate License ......................... 22\n2.3.3 Installed But Not Part of the TSF ........................................... 22\n2.4 Physical Boundary ....................................................................... 23\n2.5 Logical Boundary ........................................................................ 26\n2.5.1 Security Audit ....................................................................... 27\n2.5.2 Identification & Authentication ............................................. 27\n2.5.3 Security Management ............................................................ 27\n2.5.4 User Data Protection ............................................................. 28\n2.5.5 TOE Access .......................................................................... 28\n3 Conformance Claims ....................................................................... 29\n3.1 CC Version ................................................................................. 29\n3.2 CC Part 2 Conformant ............................................................... 29\n3.3 CC Part 3 Conformant Plus Flaw Remediation ......................... 29\n3.4 PP Claims ................................................................................... 29\n3.5 Package Claims .......................................................................... 29\n3.6 Package Name Conformant or Package Name Augmented .......... 29\n3.7 Conformance Claim Rationale ....................................................... 29\n4 Security Problem Definition .............................................................. 30\n4.1 Threats ....................................................................................... 30\n4.2 Organizational Security Policies .................................................. 30\n4.3 Secure Usage Assumptions ......................................................... 30\n4.3.1 Personnel Assumptions ........................................................ 30\n4.3.2 Connectivity Assumptions ..................................................... 31\n4.3.3 Physical Assumptions ............................................................. 31\n5 Security Objectives ........................................................................ 32\n5.1 Security Objectives for the TOE ................................................................. 32\n5.2 Security Objectives for the operational environment of the TOE .............. 32\n6 Extended Security Functional and Assurance Requirements ....................... 34\n6.1 Extended Security Functional Requirements for the TOE ......................... 34\n6.2 Extended Security Assurance Requirements ............................................ 34\n7 Security Functional Requirements .................................................................. 35\n7.1 Security Functional Requirements for the TOE ........................................ 35\n7.1.1 Class FAU: Security Audit ....................................................................... 36\n7.1.1.1 FAU_GEN.1 Audit data generation ...................................................... 36\n7.1.1.2 FAU_GEN.2 User identity association ............................................... 37\n7.1.1.3 FAU_SAR.1 Audit review .................................................................... 37\n7.1.1.4 FAU_SAR.2 Restricted audit review ................................................... 37\n7.1.1.5 FAU_SEL.1 Selective audit ................................................................. 37\n7.1.2 Class FDP: User Data Protection ............................................................ 38\n7.1.2.1 FDP_ACC.2(1) Complete access control ........................................... 38\n7.1.2.2 FDP_ACC.2 (2) Complete access control ......................................... 38\n7.1.2.3 FDP_ACF.1 (1) Security Attribute based access control ..................... 39\n7.1.2.4 FDP_ACF.1 (2) Security attribute based access control .................... 41\n7.1.3 Class FIA: Identification & Authentication ............................................... 42\n7.1.3.1 FIA_AFL.1 Authentication Failure Handling ....................................... 42\n7.1.3.2 FIA_ATD.1 User attribute definition .................................................. 42\n7.1.3.3 FIA_SOS.1 (1) Verification of Secrets ................................................ 43\n7.1.3.4 FIA_SOS.1 (2) Verification of Secrets ................................................ 44\n7.1.3.5 FIA_SOS.2 TSF Generation of Secrets ............................................... 44\n7.1.3.6 FIA_UAU.2 User authentication before any action ............................... 45\n7.1.3.7 FIA_UAU.4 Single-use authentication mechanisms ............................ 45\n7.1.3.8 FIA_UAU.5 Multiple authentication mechanisms ............................... 45\n7.1.3.9 FIA_UID.2 User identification before any action ................................. 46\n7.1.3.10 FIA_USB.1 User subject binding ..................................................... 46\n7.1.4 Class FMT: Security Management .......................................................... 47\n7.1.4.1 FMT_MOF.1 (1) Management of security functions behavior ............... 47\n7.1.4.2 FMT_MOF.1 (2) Management of security functions behavior ............... 48\n7.1.4.3 FMT_MOF.1 (3) Management of security functions behavior ............... 48\n7.1.4.4 FMT_MOF.1 (4) Management of security functions behavior ............... 48\n7.1.4.5 FMT_MSA.1 Management of security attributes ................................ 49\n7.1.4.6 FMT_MSA.3 Static attribute initialization ........................................... 49\n7.1.4.7 FMT_SMF.1 Specification of Management Functions .......................... 50\n7.1.4.8 FMT_SMR.1 Security roles ............................................................... 50\n7.1.5 Class FTA: TOE Access .......................................................................... 50\n7.1.5.1 FTA_TSE.1 TOE session establishment ............................................... 50\n7.2 Operations Defined ..................................................................................... 51\n7.2.1 Assignments Made .................................................................................. 51\n7.2.2 Iterations Made ....................................................................................... 51\n7.2.3 Selections Made ...................................................................................... 51\n7.2.4 Refinements Made .................................................................................... 51\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Title</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>8</td>\n<td>Security Assurance Requirements</td>\n<td>52</td>\n</tr>\n<tr>\n<td>8.1</td>\n<td>Security Architecture</td>\n<td>52</td>\n</tr>\n<tr>\n<td>8.1.1</td>\n<td>Security Architecture Description (ADV_ARC.1)</td>\n<td>52</td>\n</tr>\n<tr>\n<td>8.1.2</td>\n<td>Functional Specification with Complete Summary (ADV_FSP.4)</td>\n<td>52</td>\n</tr>\n<tr>\n<td>8.1.3</td>\n<td>Implementation Representation of the TSF (ADV_IMP.1)</td>\n<td>53</td>\n</tr>\n<tr>\n<td>8.1.4</td>\n<td>Architectural Design (ADV_TDS.3)</td>\n<td>54</td>\n</tr>\n<tr>\n<td>8.2</td>\n<td>Guidance Documents</td>\n<td>55</td>\n</tr>\n<tr>\n<td>8.2.1</td>\n<td>Operational User Guidance (AGD_OPE.1)</td>\n<td>55</td>\n</tr>\n<tr>\n<td>8.2.2</td>\n<td>Preparative Procedures (AGD_PRE.1)</td>\n<td>55</td>\n</tr>\n<tr>\n<td>8.3</td>\n<td>Lifecycle Support</td>\n<td>56</td>\n</tr>\n<tr>\n<td>8.3.1</td>\n<td>Authorization Controls (ALC_CMC.4)</td>\n<td>56</td>\n</tr>\n<tr>\n<td>8.3.2</td>\n<td>CM Scope (ALC_CMS.4)</td>\n<td>57</td>\n</tr>\n<tr>\n<td>8.3.3</td>\n<td>Delivery Procedures (ALC_DEL.1)</td>\n<td>57</td>\n</tr>\n<tr>\n<td>8.3.4</td>\n<td>Identification of Security Measures (ALC_DVS.1)</td>\n<td>57</td>\n</tr>\n<tr>\n<td>8.3.5</td>\n<td>Life-cycle Definition (ALC_LCD.1)</td>\n<td>58</td>\n</tr>\n<tr>\n<td>8.3.6</td>\n<td>Tools and techniques (ALC_TAT.1)</td>\n<td>58</td>\n</tr>\n<tr>\n<td>8.3.7</td>\n<td>Flaw reporting procedures (ALC_FLR.1)</td>\n<td>59</td>\n</tr>\n<tr>\n<td>8.4</td>\n<td>Security Target Evaluation</td>\n<td>59</td>\n</tr>\n<tr>\n<td>8.4.1</td>\n<td>Conformance Claims (ASE_CCL.1)</td>\n<td>59</td>\n</tr>\n<tr>\n<td>8.4.2</td>\n<td>Extended Components Definition (ASE_ECD.1)</td>\n<td>60</td>\n</tr>\n<tr>\n<td>8.4.3</td>\n<td>ST Introduction (ASE_INT.1)</td>\n<td>61</td>\n</tr>\n<tr>\n<td>8.4.4</td>\n<td>Security Objectives (ASE_OBJ.2)</td>\n<td>61</td>\n</tr>\n<tr>\n<td>8.4.5</td>\n<td>Security Requirements (ASE_REQ.2)</td>\n<td>62</td>\n</tr>\n<tr>\n<td>8.4.6</td>\n<td>Security Problem Definition (ASE_SPD.1)</td>\n<td>63</td>\n</tr>\n<tr>\n<td>8.4.7</td>\n<td>TOE Summary Specification (ASE_TSS.2)</td>\n<td>63</td>\n</tr>\n<tr>\n<td>8.5</td>\n<td>Tests</td>\n<td>64</td>\n</tr>\n<tr>\n<td>8.5.1</td>\n<td>Analysis of Coverage (ATE_COV.2)</td>\n<td>64</td>\n</tr>\n<tr>\n<td>8.5.2</td>\n<td>Basic Design (ATE_DPT.2)</td>\n<td>64</td>\n</tr>\n<tr>\n<td>8.5.3</td>\n<td>Functional Tests (ATE_FUN.1)</td>\n<td>64</td>\n</tr>\n<tr>\n<td>8.5.4</td>\n<td>Independent Testing (ATE_IND.2)</td>\n<td>65</td>\n</tr>\n<tr>\n<td>8.6</td>\n<td>Vulnerability Assessment</td>\n<td>65</td>\n</tr>\n<tr>\n<td>8.6.1</td>\n<td>Vulnerability Analysis (AVA_VAN.3)</td>\n<td>65</td>\n</tr>\n<tr>\n<td>9</td>\n<td>TOE Summary Specification</td>\n<td>67</td>\n</tr>\n<tr>\n<td>9.1</td>\n<td>TOE Security Functions</td>\n<td>67</td>\n</tr>\n<tr>\n<td>9.1.1</td>\n<td>Security Audit</td>\n<td>67</td>\n</tr>\n<tr>\n<td>9.1.1.1</td>\n<td>Security & Audit Privileges</td>\n<td>67</td>\n</tr>\n<tr>\n<td>9.1.1.2</td>\n<td>Audit/Tracking File</td>\n<td>67</td>\n</tr>\n<tr>\n<td>9.1.1.3</td>\n<td>Violations and Logging</td>\n<td>68</td>\n</tr>\n<tr>\n<td>9.1.1.4</td>\n<td>Security Event Logging</td>\n<td>68</td>\n</tr>\n<tr>\n<td>9.1.1.4.1</td>\n<td>TSSAUDIT</td>\n<td>68</td>\n</tr>\n<tr>\n<td>9.1.1.4.2</td>\n<td>TSSCPR</td>\n<td>69</td>\n</tr>\n<tr>\n<td>9.1.1.4.3</td>\n<td>TSSOERPT</td>\n<td>69</td>\n</tr>\n<tr>\n<td>9.1.1.4.4</td>\n<td>TSSPROT</td>\n<td>69</td>\n</tr>\n<tr>\n<td>9.1.1.4.5</td>\n<td>TSSRECVR</td>\n<td>69</td>\n</tr>\n<tr>\n<td>9.1.1.4.6</td>\n<td>TSSRPTST</td>\n<td>70</td>\n</tr>\n</tbody>\n</table>\n9.1.2.4 PSTKAPPL .......................................................... 77\n\n9.1.3 User Data Protection .................................................. 77\n9.1.3.1 Resource Classes .................................................. 79\n9.1.3.1.1 Resource Ownership ........................................ 80\n9.1.3.2 Security Validation Algorithm ................................ 81\n9.1.3.2.1 Volume Request Processing ................................ 81\n9.1.3.2.2 Criteria for Volumes ........................................ 82\n9.1.3.2.3 Data Set Requests ........................................... 82\n9.1.3.2.4 Criteria for Data Sets ....................................... 83\n9.1.3.2.5 General Resource Requests ................................. 84\n9.1.3.2.6 General Resources Criteria ................................. 85\n9.1.3.3 Discretionary Access Control .................................. 85\n9.1.3.3.1 Secrecs ......................................................... 85\n9.1.3.3.2 LDAP Directory Services ................................ 87\n9.1.3.4 Mandatory Access Control ..................................... 87\n9.1.3.4.1 MAC Label Dominance .................................... 88\n9.1.3.4.2 Types of MAC Label Dominance Checks ................. 89\n9.1.3.4.3 MAC Dominance Check .................................... 89\n9.1.3.4.4 Reverse MAC Dominance Check .......................... 89\n9.1.3.4.5 Equal MAC Dominance Check ............................ 90\n9.1.3.5 ACIDs .............................................................. 90\n9.1.3.5.1 Functional ACIDs .......................................... 90\n9.1.3.5.2 Organizational ACIDs ...................................... 91\n9.1.3.5.3 Model ACIDs ................................................. 92\n9.1.3.5.4 Pre-Defined ACIDs ......................................... 92\n\n9.1.4.7 TSSTRACK .................................................................. 70\n9.1.1.5 Security Reports ................................................... 70\n9.1.1.5.1 TSSCHART ...................................................... 70\n9.1.1.5.2 TSSUTIL ......................................................... 70\n9.1.1.5.3 TSSCFILE ........................................................ 71\n9.1.1.5.4 TSSREPORT and TSSREPORT2 .......................... 71\n9.1.1.5.5 TSSRPTST ........................................................ 71\n9.1.2 Identification and Authentication .................................. 71\n9.1.2.1 ACIDs .................................................................. 72\n9.1.2.2 Suspended User .................................................... 72\n9.1.2.3 Authentication Methods ......................................... 72\n9.1.2.3.1 Kerberos .......................................................... 72\n9.1.2.3.2 PassTickets ...................................................... 72\n9.1.2.3.3 Digital Certificates ............................................ 73\n9.1.2.3.4 Key Rings ....................................................... 74\n9.1.2.3.5 Certificate Associations .................................... 75\n9.1.2.3.6 Tokens ............................................................ 75\n9.1.2.3.7 Password Policy .............................................. 75\n9.1.2.3.8 Password Defaults ........................................... 76\n9.1.2.3.9 Passphrase Defaults ......................................... 76\n9.1.2.4 PSTKAPPL .......................................................... 77\n\nIdentification and Authentication\n\nACIDs\n- Model ACIDs\n- Pre-Defined ACIDs\n- Functional ACIDs\n- Organizational ACIDs\n\nAuthentication Methods\n- Kerberos\n- LDAP Directory Services\n- PassTickets\n- Digital Certificates\n- Key Rings\n- Certificate Associations\n- Tokens\n- Password Policy\n- Password Defaults\n- Passphrase Defaults\n\nResource Classes\n- Resource Ownership\n- Security Validation Algorithm\n- Volume Request Processing\n- Criteria for Volumes\n- Data Set Requests\n- Criteria for Data Sets\n- General Resource Requests\n- General Resources Criteria\n\nDiscretionary Access Control\n- Secrecs\n- LDAP Directory Services\n\nMandatory Access Control\n- MAC Label Dominance\n- Types of MAC Label Dominance Checks\n- MAC Dominance Check\n- Reverse MAC Dominance Check\n- Equal MAC Dominance Check\n\nMAC Label Dominance Checks\n- Model ACIDs\n- Pre-Defined ACIDs\n\nTSSTRACK\n\nSecurity Reports\n\nTSSCHART\n\nTSSUTIL\n\nTSSCFILE\n\nTSSREPORT and TSSREPORT2\n\nTSSRPTST\n\nUser Data Protection\n\nPSTKAPPL\n\nCA Proprietary\n9.1.3.6 Scope ........................................................................................................ 93\n9.1.3.7 Authority ................................................................................................. 94\n9.1.3.7.1 Types of Administrator Authorities ....................................................... 94\n9.1.3.7.2 Global Authorities ................................................................................ 95\n9.1.3.8 Facilities .................................................................................................. 95\n9.1.3.9 Access Restrictions .................................................................................. 97\n9.1.3.9.1 Time of Use Monitoring ......................................................................... 97\n9.1.3.9.2 Restrictions by Device ........................................................................... 97\n9.1.3.9.3 Multiple Node Users ............................................................................ 98\n9.1.3.10 Security Modes ..................................................................................... 98\n9.1.3.11 Object Reuse Protection ......................................................................... 98\n\n9.1.4 Security Management .................................................................................. 99\n9.1.4.1 Security Administrator ............................................................................ 100\n9.1.4.2 Types of Security Administrators .............................................................. 100\n9.1.4.3 Auditor ..................................................................................................... 102\n9.1.4.4 Command Functions ............................................................................... 102\n9.1.4.5 Command Propagation Facility ............................................................... 103\n\n9.1.5 TOE Access ............................................................................................... 104\n9.2 Self Protection (ADV_ARC.1) ....................................................................... 105\n9.3 TOE Summary Specification Rationale ........................................................... 106\n9.3.1 Security Audit ............................................................................................. 107\n9.3.2 User Data Protection ................................................................................... 107\n9.3.3 Identification and Authentication ................................................................. 108\n9.3.4 Security Management ................................................................................ 109\n9.3.5 TOE Access ............................................................................................... 110\n\n10 Security Problem Definition Rationale ............................................................ 111\n10.1 Security Objectives Rationale ..................................................................... 111\n10.2 Security Functional Requirements Rationale ................................................. 114\n10.3 EAL 4 Justification ....................................................................................... 120\n10.4 Requirement Dependency Rationale ............................................................. 120\n10.5 Assurance Measures .................................................................................... 120\n\n---\n\nList of Figures\n\nFigure 1-1: TOE Boundary .................................................................................. 15\nFigure 9-1: Data Set Access Requests on a Volume ............................................. 83\nFigure 9-2: General Resource Requests ............................................................... 85\n\nList of Tables\n\nTable 1-1: Customer Specific Terminology ......................................................... 12\nTable 1-2: CC Specific Terminology .................................................................... 12\nTable 1-3: Acronym Definitions .......................................................................... 13\n<table>\n<thead>\n<tr>\n<th>Table 2-1: Evaluated Components of the TOE</th>\n<th>20</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Table 2-2: Evaluated Components of the Operational Environment</td>\n<td>21</td>\n</tr>\n<tr>\n<td>Table 2-3: Minimum OS Requirements for Installation of the TOE</td>\n<td>26</td>\n</tr>\n<tr>\n<td>Table 7-1: Security Functional Requirements for the TOE</td>\n<td>36</td>\n</tr>\n<tr>\n<td>Table 7-2: User Performed Operations on the TOE</td>\n<td>39</td>\n</tr>\n<tr>\n<td>Table 7-3: Resource Classes Included in the Evaluated Configuration</td>\n<td>39</td>\n</tr>\n<tr>\n<td>Table 7-4: Mandatory Access Control</td>\n<td>41</td>\n</tr>\n<tr>\n<td>Table 7-5: CA Top Secret Generated User Security Attributes</td>\n<td>43</td>\n</tr>\n<tr>\n<td>Table 7-6: Administrative Functions on the TOE</td>\n<td>49</td>\n</tr>\n<tr>\n<td>Table 9-1: Resource Classes Included in the Evaluated Configuration</td>\n<td>79</td>\n</tr>\n<tr>\n<td>Table 9-2: Access Modes</td>\n<td>86</td>\n</tr>\n<tr>\n<td>Table 9-3: Mandatory Access Control</td>\n<td>87</td>\n</tr>\n<tr>\n<td>Table 9-4: Security Administrators and Associated Scope of Authority</td>\n<td>94</td>\n</tr>\n<tr>\n<td>Table 9-5: Facility Resources</td>\n<td>97</td>\n</tr>\n<tr>\n<td>Table 9-6: User Performed Operations on the TOE</td>\n<td>99</td>\n</tr>\n<tr>\n<td>Table 9-7: Security Functional Components</td>\n<td>107</td>\n</tr>\n<tr>\n<td>Table 10-1: Assumption to Objective Mapping</td>\n<td>111</td>\n</tr>\n<tr>\n<td>Table 10-2: Threat to Objective Mapping</td>\n<td>114</td>\n</tr>\n<tr>\n<td>Table 10-3: Security Functional Requirements Rationale</td>\n<td>120</td>\n</tr>\n<tr>\n<td>Table 10-4: Assurance Requirements Evidence</td>\n<td>125</td>\n</tr>\n</tbody>\n</table>\n1 Security Target Introduction\n\nThis chapter presents the Security Target (ST) identification information and an overview. An ST contains the Information Technology (IT) security requirements of an identified Target of Evaluation (TOE) and specifies the functional and assurance security measures offered by the TOE.\n\n1.1 ST Reference\n\nThis section provides information needed to identify and control this ST and its Target of Evaluation. This ST targets Evaluation Assurance Level 4 (EAL4).\n\n1.1.1 ST Identification\n\nST Title: CA Top Secret for z/OS r14\nST Version: 1.1\nST Publication Date: March 7, 2011\nST Author: Booz Allen Hamilton\n\n1.1.2 Document Organization\n\nChapter 1 of this ST provides identifying information for the CA Top Secret® for z/OS r14. It includes an ST Introduction, ST Reference, ST Identification, TOE Reference, TOE Overview, and TOE Type.\n\nChapter 2 describes the TOE Description, which includes the physical and logical boundaries, and describes the components and/or applications that are excluded from the evaluated configuration.\n\nChapter 3 describes the conformance claims made by this ST.\n\nChapter 4 describes the Security Problem Definition as it relates to threats, Operational Security Policies, and Assumptions met by the TOE.\n\nChapter 5 identifies the Security Objectives of the TOE and of the Operational Environment.\n\nChapter 6 describes the Extended Security Functional Requirements (SFR) and Security Assurance Requirements (SAR).\n\nChapter 7 describes the Security Functional Requirements.\n\nChapter 8 describes the Security Assurance Requirements.\n\nChapter 9 is the TOE Summary Specification (TSS), a description of the functions provided by CA Top Secret® r14 SP1 for z/OS to satisfy the SFRs and SARs.\nChapter 10 is the Security Problem Definition Rationale and provides a rationale or pointers to a rationale, for security objectives, assumptions, threats, requirements, dependencies, and PP claims for the chosen EAL, any deviations from CC Part 2 concerning SFR dependencies, and a mapping of threats to assumptions, objectives, and SFRs. It also identifies the items used to satisfy the Security Assurance Requirements for the evaluation.\n\n### 1.1.3 Terminology\n\nThis section defines the terminology used throughout this ST. The terminology used throughout this ST is defined in Table 1-2: Terminology Definitions. This table is to be used by the reader as a quick reference guide for terminology definitions.\n\n<table>\n<thead>\n<tr>\n<th>Terminology</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Access</td>\n<td>Access indicates an ACID’s ability to use a resource.</td>\n</tr>\n<tr>\n<td>ACID</td>\n<td>An ACID is a unique character-string identifier by which CA Top Secret identifies a user's Security Record.</td>\n</tr>\n<tr>\n<td>ACID Authorities</td>\n<td>ACID Authorities specify what actions security administrators can perform on ACIDs within their scope.</td>\n</tr>\n<tr>\n<td>ACID Type</td>\n<td>An ACID type determines an ACID's function in the Security File structure. Types include User, Profile, Department, Zone, DCA, VCA,</td>\n</tr>\n<tr>\n<td></td>\n<td>ZCA, LSCA, SCA, and MSCA.</td>\n</tr>\n<tr>\n<td>Administrator</td>\n<td>An administrator is a user with privileges to manage the TOE, TOE data, and other TOE users. This includes security administrators (MSCA,</td>\n</tr>\n<tr>\n<td></td>\n<td>SCA type ACIDs) and scoped security administrators (LSCA, DCA, VCA, ZCA type ACIDs). It can also include individual users that have been</td>\n</tr>\n<tr>\n<td></td>\n<td>assigned admin privileges.</td>\n</tr>\n<tr>\n<td>Administrative authority</td>\n<td>Administrative authority indicates the different classes of authority that are assigned via the TSS ADMIN command function. This field</td>\n</tr>\n<tr>\n<td></td>\n<td>determines the functions a security administrator can perform.</td>\n</tr>\n<tr>\n<td>ALL Record</td>\n<td>The ALL Record contains global access requirements that are effective for all users.</td>\n</tr>\n<tr>\n<td>Attribute</td>\n<td>An attribute is a specific authority, privilege, or restriction that is assigned to an ACID.</td>\n</tr>\n<tr>\n<td>Auditor</td>\n<td>An authorized user or administrator with the audit privilege.</td>\n</tr>\n<tr>\n<td>Authorization</td>\n<td>Authorization is how CA Top Secret allows access to a protected resource.</td>\n</tr>\n<tr>\n<td>Batch</td>\n<td>Batch is a method of processing large amounts of data at one time for jobs too large to perform immediately online.</td>\n</tr>\n<tr>\n<td>Central Security Control</td>\n<td>An SCA is an administrator whose scope of authority includes the entire installation. An SCA can designate and authorize VCAs and DCAs.</td>\n</tr>\n<tr>\n<td>ACID</td>\n<td>CICS is a teleprocessing monitor that can be used for a variety of applications. It is a transaction manager designed for rapid, high-volume</td>\n</tr>\n<tr>\n<td></td>\n<td>online processing.</td>\n</tr>\n<tr>\n<td>Certificate Name Filtering</td>\n<td>CNF allows administrators the ability to associate certificates with users without having to add each certificate to the CA Top Secret security file.</td>\n</tr>\n<tr>\n<td>Database</td>\n<td>A database is a systemized collection of data stored for immediate access.</td>\n</tr>\n<tr>\n<td>Data set</td>\n<td>A data set is a group of logically related records stored together and given a unique name.</td>\n</tr>\n<tr>\n<td>Default</td>\n<td>Default is a value or action the computer system automatically supplies unless an administrator specifies an alternative.</td>\n</tr>\n<tr>\n<td>Term</td>\n<td>Definition</td>\n</tr>\n<tr>\n<td>--------------------------</td>\n<td>--------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Department</td>\n<td>A department is a mandatory collection of users and profiles that a department ACID defines. A department cannot sign on and does not have a password, but it can own resources.</td>\n</tr>\n<tr>\n<td>Department Control ACID</td>\n<td>A Department Control ACID is used where security administration has been decentralized. The DCA's scope of authority is limited to the assigned department.</td>\n</tr>\n<tr>\n<td>Division</td>\n<td>A division is an optional collection of departments that a divisional ACID defines. A division cannot sign on and does not have a password, but it can own resources.</td>\n</tr>\n<tr>\n<td>Divisional Control ACID</td>\n<td>A VCA is an ACID used where security administration has been decentralized. The VCA's scope of authority is limited to an assigned division, including the departments attached to it.</td>\n</tr>\n<tr>\n<td>Entity</td>\n<td>An entity is the name of an object as referenced by the system and security.</td>\n</tr>\n<tr>\n<td>Facility</td>\n<td>A way of grouping options associated with a particular service that users sign on to.</td>\n</tr>\n<tr>\n<td>Fail mode</td>\n<td>FAIL mode indicates that CA Top Secret is in full control of all access requests. Violations result in termination of the request.</td>\n</tr>\n<tr>\n<td>Field Description Table</td>\n<td>The FDT contains all dynamically and pre-defined fields identified to CA Top Secret.</td>\n</tr>\n<tr>\n<td>Global access</td>\n<td>Global access indicates any access specified in the ALL Record.</td>\n</tr>\n<tr>\n<td>Integrated Cryptographic Services Facility</td>\n<td>ICSF is a component of z/OS and ships with the base product. It is the software component that provides access to the zSeries crypto hardware.</td>\n</tr>\n<tr>\n<td>Information Management System</td>\n<td>IBM Information Management System (IMS) is a joint hierarchical database and information management system with extensive transaction processing capabilities.</td>\n</tr>\n<tr>\n<td>Job Control Language</td>\n<td>The computer language that instructs the system how to run a job, assigning files to specific devices and describing each file in detail to the system.</td>\n</tr>\n<tr>\n<td>Limited Central Security Control ACID</td>\n<td>LSCA is a control ACID can have all the authority of an SCA, but unlike the SCA, the LSCA can have a limited scope of control. Only the MSCA can determine that scope and it can encompass ZCAs, VCAs, DCAs, Profiles, Users, and other LSCAs.</td>\n</tr>\n<tr>\n<td>Limited Command Facility</td>\n<td>LCF is a facility that allows the security administrator to control use of commands/transactions (TSO, CICS, and so on) available to a user.</td>\n</tr>\n<tr>\n<td>Locktime</td>\n<td>Locktime indicates the period of time after which a terminal automatically locks if no transactions or commands are issued. The user must issue TSS UNLOCK and supply a valid password to unlock the terminal.</td>\n</tr>\n<tr>\n<td>Master Security Control ACID</td>\n<td>MSCA is the one Control ACID that is predefined, active, and assigned full administrative authority the first time CA Top Secret starts. This administrator's scope of authority includes the entire installation. The MSCA can designate and authorize SCAs, LSCAs, ZCAs, VCAs, and DCAs.</td>\n</tr>\n<tr>\n<td>Multi-level security</td>\n<td>Multi-Level Security (MLS) is a security policy that prevents disclosure and declassification of data based on defined levels of sensitivity of data and levels of clearance of users to that data.</td>\n</tr>\n<tr>\n<td>Node Description Table</td>\n<td>The NDT contains all PassTicket, LDAP and CPF information.</td>\n</tr>\n<tr>\n<td>Object</td>\n<td>Any resource protected by the TOE.</td>\n</tr>\n<tr>\n<td>Ownership</td>\n<td>Ownership indicates when an ACID has unlimited access to the resource. Ownership defines the resource to CA Top Secret. All other ACIDs must be specifically authorized to access the resource.</td>\n</tr>\n<tr>\n<td>Passphrase</td>\n<td>A passphrase is a password that can be longer than eight characters and can contain blanks.</td>\n</tr>\n<tr>\n<td>PassTicket</td>\n<td>A method of authentication the TOE utilizes which is issued for specific session and cannot be used again once that session has ended. In order to</td>\n</tr>\n<tr>\n<td><strong>Permissions</strong></td>\n<td>Permissions make an owned resource available to other users in a controlled manner.</td>\n</tr>\n<tr>\n<td><strong>Profile</strong></td>\n<td>A profile is an ACID containing a collection of access characteristics common to several users. It generally describes the access characteristics of a particular job function. A profile cannot sign on and does not have a password. Up to 254 profiles can be attached to a user's ACID. Any number of users can be associated with a single profile.</td>\n</tr>\n<tr>\n<td><strong>RACROUTE</strong></td>\n<td>The RACROUTE macro is the interface to RACF (or another external security manager) for z/OS.</td>\n</tr>\n<tr>\n<td><strong>Record</strong></td>\n<td>CA Top Secret supports several different record types. They include the main Security Record for each ACID, the Audit Record, the ALL Record, the Profile Record, the Department, Division, and Zone Records, the Resource Descriptor Table Record, and the Control ACID's Records.</td>\n</tr>\n<tr>\n<td><strong>Recovery File</strong></td>\n<td>The Recovery File contains a record of all changes made to the Security File. It is used to recreate the Security File if it becomes damaged or unusable because of hardware or software problems.</td>\n</tr>\n<tr>\n<td><strong>Resource</strong></td>\n<td>A resource is any component of the computing or operating system required by a task. For the purposes of data protection, these resources are the objects reside on the system.</td>\n</tr>\n<tr>\n<td><strong>Resource Access Control Facility</strong></td>\n<td>RACF is an IBM program product that provides system entry, resource access control, auditing, accountability, and administrative control for the z/OS operating system.</td>\n</tr>\n<tr>\n<td><strong>Resource Descriptor Table</strong></td>\n<td>The RDT contains all dynamically and pre-defined resources identified to CA Top Secret.</td>\n</tr>\n<tr>\n<td><strong>Scope of authority</strong></td>\n<td>Scope of authority indicates what logical units the user has administrative control over.</td>\n</tr>\n<tr>\n<td><strong>Secrec</strong></td>\n<td>See “Security Record.”</td>\n</tr>\n<tr>\n<td><strong>Security administrator</strong></td>\n<td>A security administrator is primarily responsible for implementation and maintenance functions such as defining users, resources, and levels of access. The administrative authority determines what the security administrator can do.</td>\n</tr>\n<tr>\n<td><strong>Security file</strong></td>\n<td>A Security File is a Security Database consisting of the Security Records that contain all user and resource permissions and restrictions.</td>\n</tr>\n<tr>\n<td><strong>Security label</strong></td>\n<td>Security labels classify users, data, and resources. Standard access rules and permissions still apply, but only after MAC label dominance checks determine that a user can access data and resources based on their security label and the security label of the data or resources the user wants to access.</td>\n</tr>\n<tr>\n<td><strong>Security record (secrec)</strong></td>\n<td>A Security Record is part of the Security File that contains a set of user and profile records copied into a user's address space, including information such as resources a particular user can access and how the user can use them. This information also contains user characteristics, authorities, and so on. Also known as "secrec."</td>\n</tr>\n<tr>\n<td><strong>Security validation algorithm</strong></td>\n<td>The Security Validation Algorithm determines whether CA Top Secret should accept or deny users' requests to use a resource such as a data set.</td>\n</tr>\n<tr>\n<td><strong>Source of origin</strong></td>\n<td>Source or origin indicates the location of an access request (a terminal or reader).</td>\n</tr>\n<tr>\n<td><strong>Started Task Command Record</strong></td>\n<td>The Started Task Command (STC) Record is a reserved or special ACID that defines a z/OS started task command to CA Top Secret.</td>\n</tr>\n<tr>\n<td><strong>SYSID (System Identifier)</strong></td>\n<td>SYSID: A maximum of four characters may be specified and the value may contain an asterisk (*) for masking. This keyword is used along with certificate name filtering (CNF).</td>\n</tr>\n<tr>\n<td><strong>Time Sharing Option</strong></td>\n<td>TSO enables two or more users to execute their programs at the same time.</td>\n</tr>\n</tbody>\n</table>\nby dividing the machine resources among terminal users.\n\n<table>\n<thead>\n<tr>\n<th>Term</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>User</td>\n<td>A user is the lowest ACID level in the security structure. Generally, a user can sign on via a password, initiate jobs, and belong to a department.</td>\n</tr>\n<tr>\n<td>User Attribute Data Set</td>\n<td>In TSO, UADS is a partitioned data set with a member for each authorized user. Each member contains the appropriate passwords, user definitions, account numbers, LOGON procedure names, and user characteristics that define the user profile.</td>\n</tr>\n<tr>\n<td>Violation</td>\n<td>A violation is an unauthorized attempt to access a protected resource.</td>\n</tr>\n<tr>\n<td>Zone</td>\n<td>A zone is an optional collection of divisions defined by a zone ACID. It cannot sign on and does not have a password, but it can own resources.</td>\n</tr>\n<tr>\n<td>Zone Control ACID</td>\n<td>A ZCA is an administrative ACID whose scope of authority includes an entire zone.</td>\n</tr>\n</tbody>\n</table>\n\nTable 1-1: Customer Specific Terminology\n\n<table>\n<thead>\n<tr>\n<th>Term</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Authorized user</td>\n<td>A user who may, in accordance with the TSP, perform an operation. This is an end user or an administrator.</td>\n</tr>\n<tr>\n<td>External IT entity</td>\n<td>Any IT product or system, untrusted or trusted, outside of the TOE that interacts with the TOE.</td>\n</tr>\n<tr>\n<td>Role</td>\n<td>A predefined set of rules establishing the allowed interactions between an end user and the TOE.</td>\n</tr>\n<tr>\n<td>TOE Security Functions (TSF)</td>\n<td>A set consisting of all hardware, software, and firmware of the TOE that must be relied upon for the correct enforcement of the TSP.</td>\n</tr>\n<tr>\n<td>User</td>\n<td>Any entity (human user or external IT entity) outside the TOE that interacts with the TOE.</td>\n</tr>\n</tbody>\n</table>\n\nTable 1-2: CC Specific Terminology\n\n1.1.4 Acronyms\n\nThe acronyms used throughout this ST are defined in Table 1-3: Acronym Definitions. This table is to be used by the reader as a quick reference guide for acronym definitions.\n\n<table>\n<thead>\n<tr>\n<th>Acronym</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ACID</td>\n<td>Accessor ID</td>\n</tr>\n<tr>\n<td>APPC</td>\n<td>Advanced Program-to-Program Communication</td>\n</tr>\n<tr>\n<td>ATF</td>\n<td>Audit Tracking File</td>\n</tr>\n<tr>\n<td>CC</td>\n<td>Common Criteria</td>\n</tr>\n<tr>\n<td>CCEVS</td>\n<td>Common Criteria Evaluation and Validation Scheme</td>\n</tr>\n<tr>\n<td>CCIMB</td>\n<td>Common Criteria Interpretations Management Board</td>\n</tr>\n<tr>\n<td>CICS</td>\n<td>Customer Information Control System</td>\n</tr>\n<tr>\n<td>CNF</td>\n<td>Certificate Name Filtering</td>\n</tr>\n<tr>\n<td>CPF</td>\n<td>Command Propagation Facility</td>\n</tr>\n<tr>\n<td>DAC</td>\n<td>Discretionary Access Control</td>\n</tr>\n<tr>\n<td>DCA</td>\n<td>Departmental Control ACID</td>\n</tr>\n<tr>\n<td>DLF</td>\n<td>Data Lookaside Table</td>\n</tr>\n<tr>\n<td>EAL</td>\n<td>Evaluation Assurance Level</td>\n</tr>\n<tr>\n<td>FDT</td>\n<td>Field Description Table</td>\n</tr>\n</tbody>\n</table>\n### Table 1-3: Acronym Definitions\n\n<table>\n<thead>\n<tr>\n<th>Acronym</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ICSF</td>\n<td>Integrated Cryptographic Services Facility</td>\n</tr>\n<tr>\n<td>IMS</td>\n<td>Information Management System</td>\n</tr>\n<tr>\n<td>JCL</td>\n<td>Job Control List</td>\n</tr>\n<tr>\n<td>JES</td>\n<td>Job Entry Subsystem</td>\n</tr>\n<tr>\n<td>LCF</td>\n<td>Limited Command Facility</td>\n</tr>\n<tr>\n<td>LDAP</td>\n<td>Lightweight Directory Access Protocol</td>\n</tr>\n<tr>\n<td>LSCA</td>\n<td>Limit Central Security Control ACID</td>\n</tr>\n<tr>\n<td>MAC</td>\n<td>Mandatory Access Control</td>\n</tr>\n<tr>\n<td>MLS</td>\n<td>Multi-level Security</td>\n</tr>\n<tr>\n<td>MSCA</td>\n<td>Master Security Control ACID</td>\n</tr>\n<tr>\n<td>MSM</td>\n<td>Mainframe Software Manager</td>\n</tr>\n<tr>\n<td>MVS</td>\n<td>Multiple Virtual Storage</td>\n</tr>\n<tr>\n<td>NDT</td>\n<td>Node Description Table</td>\n</tr>\n<tr>\n<td>PPT</td>\n<td>Program Properties Table</td>\n</tr>\n<tr>\n<td>RACF</td>\n<td>Resource Access Control Facility</td>\n</tr>\n<tr>\n<td>RDT</td>\n<td>Resource Descriptor Table</td>\n</tr>\n<tr>\n<td>SAF</td>\n<td>System Authorization Facility</td>\n</tr>\n<tr>\n<td>SCA</td>\n<td>Central Security Control ACID</td>\n</tr>\n<tr>\n<td>SDT</td>\n<td>Static Data Table</td>\n</tr>\n<tr>\n<td>SMF</td>\n<td>System Management Facility</td>\n</tr>\n<tr>\n<td>ST</td>\n<td>Security Target</td>\n</tr>\n<tr>\n<td>STC</td>\n<td>Started Task Command</td>\n</tr>\n<tr>\n<td>SYSID</td>\n<td>System Identifier</td>\n</tr>\n<tr>\n<td>TMP</td>\n<td>Terminal Monitor Program</td>\n</tr>\n<tr>\n<td>TOE</td>\n<td>Target of Evaluation</td>\n</tr>\n<tr>\n<td>TSC</td>\n<td>TOE Scope of Control</td>\n</tr>\n<tr>\n<td>TSF</td>\n<td>TOE Security Function</td>\n</tr>\n<tr>\n<td>TSO</td>\n<td>Time-sharing option</td>\n</tr>\n<tr>\n<td>UADS</td>\n<td>User Attribute Data Set</td>\n</tr>\n<tr>\n<td>VCA</td>\n<td>Divisional Control ACID</td>\n</tr>\n<tr>\n<td>VSAM</td>\n<td>Virtual Storage Access Method</td>\n</tr>\n<tr>\n<td>ZCA</td>\n<td>Zonal Control ACID</td>\n</tr>\n</tbody>\n</table>\n\n### 1.1.5 References\n\n\n[6] CA Top Secret for z/OS Control Options Guide r14\n\n[7] CA Top Secret for z/OS Cookbook r14\n\n[8] z/OS Planning for Installation Version 1 Release 11\n1.1.6 CC Concepts\n\nThe following are CC concepts as used in this document. A Subject is any user of the TOE (account, user, administrative user, applications or process issuing RACROUTE call). An Object (i.e., resource or entity) can be a dataset, volume, command issued by a user, etc. An Operation is any action on a resource (e.g. read, write, create, fetch, update, control, alter, or scratch). A Security Attribute is information such as username, groups, profiles, facilities, passwords, etc. that is kept in the security file for the user. An External Entity is anything outside of the TOE that affects the TOE.\n\n1.2 TOE Reference\n\n1.2.1 TOE Identification\n\nCA Top Secret® r14 SP1 for z/OS\n\n1.3 TOE Overview\n\nCA Top Secret® r14 SP1 for z/OS, herein referred to as CA Top Secret, delivers access control software for z/OS operating systems and includes interfaces for TSO, CICS, and IMS.\n\nThe TOE allows administrators to control user access to protected resources such as datasets and volumes and their associated data. User access is controlled via Top Secret intercepts of commands issued by the users or applications acting on behalf of the users running in z/OS.\n\nThe TOE:\n\n- Provides a platform for access control to protected data resources\n- Integrates with and operates as a policy enforcement mechanism of the z/OS MVS Operating System. CA Top Secret is the called by z/OS for all security access control checks made by the operating system. No action is allowed to be performed by users and administrators of z/OS without access to CA Top Secret for an authorization decision\n- Records all policy enforcement decisions made by z/OS and stores the decisions in the z/OS database\n- Maintains a database of all users and their associated security attributes\n- Protects critical data sets and resources so that only the appropriate people have access to them\n- Reports on any unauthorized access attempts\n• Provides protection against unauthorized destruction, disclosure, or modification of data and resources\n\nFigure 1-1: TOE Boundary\n\nAs illustrated in Figure 1-1, there are two types of users of the TOE: administrators and users. A user must be granted an administrative privilege in order to be considered an administrator. Once given an administrative privilege, an administrator can then manage the TOE based on the permissions assigned to them. Security administrators manage the entire TOE and its users, whereas Scoped Security Administrators can only perform operations defined within their scope. A non-administrator user accesses the TOE strictly to perform work. For more information on administrators of the TOE, see Section 9.1.4.1.\n\nUsers and Security Administrators can access the TOE through the Console Address Space and/or Application process. The Console Address Space is a z/OS facility that provides a callable interface that lets MVS applications communicate with other applications using Advanced Program-to-Program Communication. When attempting to communicate through the console to Console Address Space locally, RACROUTE is called to check the permissions of the user or administrator to ensure that they are allowed to access the TOE or perform the action. If the user or administrator were attempting to access the TOE remotely, they would communicate through the terminal to\n\nBooz Allen Hamilton CCTL – CA Proprietary\nthe Application process, which is used for callable services, RACROUTE macros, and RAC SVCs.\n\nThe components within the TOE include System Authorization Facility (SAF), Command Propagation Facility (CPF), operator communications, and LDAP Directory Services (LDS). The SAF component is used by the TOE to get control of SAF calls before the z/OS router so that it can determine how to process the calls. The CPF facility routes security administration to all or selected nodes, resulting in single-point administration. Changes made to ACIDs, passwords, or access levels can be propagated to all nodes to which the user is defined. CA Top Secret operator communications calls are performed with operator communications.\n\nThe Operational Environment (OE) consists of the following components: z/OS, Console Address Space, Application Process (i.e. third party applications), Kerberos, z/OS SMF File, CA Top Secret Security File, console, terminal, and system clock. Kerberos verifies requests as a trusted third-party authentication service. CA Top Secret keeps this information in the Security File. The records are administered through the CA Top Secret TSS command. There are two types of file storage records that contain the information that can be requested through SAF: the User ACID record and the Profile ACID record.\n\nApplications running on top of the z/OS operating system also make calls to the TOE. All calls to the TOE are used to restrict all unauthorized access to TOE objects.\n\nCA Top Secret uses the following files:\n\n- **Security File** – A security database consisting of the security records that contain all user and resource permissions and restrictions. When a user initiates a job or signs on to an online facility in a z/OS environment, CA Top Secret obtains the user's security record from the security file, and places it in the user's address space for the duration of the session.\n\n- **Parameter File** - Stores and defines control options at initialization and sets up the operating environment for CA Top Secret.\n\n- **Audit/Tracking File** - Records security-related events and can be shared among CPUs. These events include violations, job and session initiation, and resource access.\n\n- **Backup File** - Stores the automatic daily backup of the security file to ensure complete integrity of the security environment. The backup file is an exact copy of the security file as it existed at the time of the last backup, and it can be used if the device containing the security file becomes unavailable.\n\n- **Recovery File** - Stores recent administrative commands, depending on the size of the file allocated. The backup security file with the application of select recovery file commands can completely restore a damaged security file. This is a wraparound file.\n- **$LOG$** File - When CA Top Secret starts under the Job Entry Subsystem (JES), it dynamically allocates a SYSOUT file with a DDNAME of $LOG$. This file contains:\n - All modifications to the CA Top Secret default control options originating from:\n - CA Top Secret Parameter File\n - Console operator command modification of CA Top Secret task\n - Online administrator TSS command modification\n - Status messages for the CA Top Secret task regarding:\n - Security File capacity and backup\n - Audit/Tracking File capacity and backup\n - I/O errors in CA Top Secret files during task execution\n\n- **Command Propagation Files** - Two types of files are associated with the command propagation facility (CPF). These files must be dedicated to a single CPU.\n - CPF Recovery File - A disk file the CPF uses to save transmitted commands until a response to those commands has been received from remote nodes.\n - CPF Journal Files - These files provide an historical record of the command traffic to and from a particular CA Top Secret CPF node. One receives journal records commands and their response from other nodes. A send journal can exist for each connected node to record commands and responses.\n\nThe following security classes are enforced by the TOE: Security Audit, Identification & Authentication, User Data Protection, Security Management, and TOE Access. For an explanation of each of these security classes, see section 2.5 Logical Boundary.\n\nThe TOE also ensures that information critical for the security of subjects receives protection via the operational environment’s cryptographic mechanisms. The TOE will call the z/OS ICSF module when any security relevant information requires encryption. The ICSF component is not part of the TOE.\n\n### 1.4 TOE Type\n\nThe TOE type for CA Top Secret for z/OS is System Access Control. System Access Control is defined by CCEVS as “A technique used to define or restrict the rights of individuals or application programs to obtain data from, or place data onto, a storage device. The definition or restriction of the rights of individuals or application programs to obtain data from, or place data into, a storage device. Limiting access to information system resources only to authorized users, programs, processes, or other systems.”\n## 2 TOE Description\n\n### 2.1 Evaluated Components of the TOE\n\nThe following table describes the TOE components in the evaluated configuration:\n\n<table>\n<thead>\n<tr>\n<th>Component</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>System Authorization Facility (SAF)</td>\n<td>The IBM System Authorization Facility (SAF) provides a system wide interface to CA Top Secret. The CA SAF Router (A component of CA Top Secret) intercepts and passes all RACROUTE calls to CA Top Secret. CA Top Secret processes all SAF calls by default. This enables CA Top Secret to manage all of the unique processing needed to provide full security coverage for the z/OS platform.</td>\n</tr>\n<tr>\n<td>CA Top Secret Operator Communications</td>\n<td>CA Top Secret has three primary operator commands. They are START, STOP, and MODIFY. These commands have multiple sub-functions that are controlled by the CA Top Secret and allow for configuration setup, configuration changes and shut down options. Authorization is required to perform that function. In addition there are a number of commands that establish and configure CA SAF tracing. These are also controlled by CA Top Secret and require specific authorization. The CA SAF Sectrace commands are as follows: SECTRACE DELETE, SECTRACE DISABLE, SECTRACE DISPLAY, SECTRACE LOGERR, SECTRACE MODIFY, SECTRACE NOLOGERR, and SECTRACE SET.</td>\n</tr>\n<tr>\n<td>Command Propagation Facility (CPF)</td>\n<td>Routes security administration to all or selected nodes synchronously or asynchronously, resulting in single-point administration. Changes made to ACIDs, passwords, or access levels can be propagated to all nodes to which the user is defined. For example, USER01 is defined to two nodes, with NODE A as the local node and NODE B as the remote node. If the user changes the password on NODE A, CPF automatically propagates the change to NODE B. Through the use of command function keywords, a user can specify which node receives these commands and how the local node processes them. The Command Propagation Facility (CPF) component of CA Top Secret uses the CAI Common Communications Interface (CAICCI) as the communications layer from one system to the other. CA Top Secret puts a request packet together and sends it though CCI. CCI sits on both systems to perform ‘receive’ and ‘send’ functions.</td>\n</tr>\n</tbody>\n</table>\n### Common Services\n\nCommon Services is a set of common components used by a number of CA’s Mainframe products. It is free but requires a separate install. Top Secret uses three components in the CA Common Services product line.\n\nThe CICS interface for CA Top Secret uses the CAIENF/CICS subcomponent of CAIENF to gain control of security calls implanted within CICS by CAIENF/CICS. This component then calls the TSS CICS interface to process the security call.\n\nThe CA Event Notification Facility (CAIENF) is an operating system interface service that enables CA applications to obtain event data from z/OS and subsystems such as CICS and TSO.\n\nThe CAI Common Communications Interface (CAICCI) is a communications facility that offers a simple and flexible approach enabling CA products to communicate with one another. This facility provides a layer that isolates application software from the specifics of the communications environment.\n\nCAICCI features include:\n\n- Single point of control\n- Multiple platforms support\n- Performance optimization\n- Peer-to-peer (program to program) communication\n- Parallel conversations\n- Dynamic installation configuration\n- Ease of customization\n- Error handling\n\n### LDAP Directory Services (LDS)\n\nAn LDAP directory provides a method to maintain directory information, such as email accounts, in a central location, for storage, update, retrieval, and exchange. LDAP directories can be utilized as network accessible databases for organization and indexing of network security information. As LDAP is becoming an integral part of most networks, CA Top Secret provides the LDAP Directory Services (LDS) option.\n\nLDS is the functionality that allows CA Top Secret to interface with and transmit data to the remote repository. Unlike other products and services that...\nuse pull technology on a scheduled basis; this is a proactive approach that pushes the change as it occurs, providing a real-time update of the changed data.\n\nTable 2-1: Evaluated Components of the TOE\n\n<table>\n<thead>\n<tr>\n<th>Component</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Kerberos</td>\n<td>Network Authentication and Privacy Service, known as Kerberos, uses CA Top Secret to store and administer information about principals and realms. REALM and KERBLINK records have been incorporated into CA Top Secret to store this information. The REALM record is used to store information about Network Authentication and Privacy Service principals on the local system. The KERBLINK record lets a user map principals to CA Top Secret users on a system. Kerberos for z/OS verifies requests as a trusted third-party authentication service. Using conventional shared secret key cryptography, Kerberos confirms the identities of principals (users), without relying on authentication by the host operating system, without basing trust on host addresses, without necessitating physical security of all hosts on the network, and under the premise that packets traveling along the network can be read, changed, and inserted at will.</td>\n</tr>\n<tr>\n<td>Console Address Space</td>\n<td>Console Address Space is a z/OS facility that provides a callable interface that lets MVS applications communicate with other applications using Advanced Program-to-Program Communication (APPC). These other applications can reside in or outside of the mainframe. The MVS console can change global configuration parameters of the TOE via a modify MVS command.</td>\n</tr>\n<tr>\n<td>z/OS v1 r11</td>\n<td>A 64-bit operating system for mainframe computers, created by IBM, under which the TOE operates. The z/OS operating system also provides its encryption and decryption methods which the TOE employs.</td>\n</tr>\n</tbody>\n</table>\n\n2.2 Components and Applications in the Operational Environment\n\nThe following table lists components and applications in the environment that the TOE relies upon in order to function properly:\n### Table 2-2: Evaluated Components of the Operational Environment\n\n<table>\n<thead>\n<tr>\n<th>Component</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Console</td>\n<td>The local interface used by users of the TOE to access CA Top Secret through the Console Address Space for management and audit functionality</td>\n</tr>\n<tr>\n<td>Terminal</td>\n<td>The remote interface used by users of the TOE to access CA Top Secret directly or via the Application Process</td>\n</tr>\n<tr>\n<td>Application Process</td>\n<td>This includes all third party application processes which TOE users and administrators perform actions on which are monitored by the TOE for authentication, authorization, and in some instances management of objects through the TOE.</td>\n</tr>\n</tbody>\n</table>\n\n### 2.3 Excluded from the TOE\n\nThe following optional products, components, and/or applications can be integrated with CA Top Secret but are not included in the evaluated configuration. They provide no added security related functionality. They are separated into three categories: not installed, installed but requires a separate license, and installed but not part of the TSF.\n\n#### 2.3.1 Not Installed\n\nThese components are not installed with CA Top Secret and are therefore not included in the TOE boundary.\n\n- **ELM Integration** - Enterprise Log Manager is a separate product that collects and stores logs from various endpoints using agents configured with connectors.\n\n- **CA Compliance Manager for z/OS Integration** – CA Compliance Manager for z/OS allows Administrators to collect, and report on security relevant activity, and generate alerts requiring action when possible compliance violations occur. It is an independent product that requires its own license and is not included in the evaluated configuration of the TOE.\n\n- **CA Top Secret® Option for DB2** – Protects several DB2 resources and replaces GRANT/REVOKE processing. PERMIT commands are written in place of GRANT commands and a conversion utility provides a transition. A catalog synchronization utility brings DB2 catalog entries up-to-date with CA Top Secret® Option for DB2 authorizations.\n\n- **DFSMS** – IBM Subsystem. With DFSMS, the z/OS administrator can define performance goals and data availability requirements, create model data definitions for typical data sets, and automate data backup. DFSMS can\nautomatically assign, based on installation policy, those services and data definition attributes to data sets when they are created.\n\n- **Event Notification Facility (ENF)** - An operating system interface component CA Top Secret uses to obtain data from z/OS. CAIENF provides the VTAM facilities to transmit and receive CA Top Secret TSS commands when using the Command Propagation Facility.\n\n- **Standard Security Facility (SSF)** - A facility that provides an application interface for CA and non-CA products to obtain and use CA Top Secret information.\n\n### 2.3.2 Installed but Requires a Separate License\n\nThere are no components that are installed with CA Top Secret that require a separate license.\n\n### 2.3.3 Installed But Not Part of the TSF\n\nThese components are installed with CA Top Secret, but are not included in the TSF.\n\n- **Group** – Group is not commonly used. The intent is for its use is for backward compatibility. It is not used for object access.\n\n- **User Attribute Data Set (UADS)** – In TSO, UADS is a partitioned data set with a member for each authorized user. Each member contains the appropriate passwords, user definitions, account numbers, LOGON procedure names, and user characteristics that define the user profile. This is an obsolete capability.\n\n- **SYSPLEX** – The coupling facility is a feature of MVS/ESA that allows systems in a sysplex environment to communicate and share data with each other. It allows multiple systems to share one security file. Security in a sysplex environment is based on:\n - The communication function or Cross System Coupling Facility (XCF) that provides a way for each system in the sysplex to send messages or signals to all other systems.\n - The data sharing function or Cross System Extended Services (XES) that provides the ability for systems in the sysplex to share common data that would normally be obtained from a database. This function saves system resources by reducing I/O to the database.\n• **Security Modes** – The following security modes are not security enforcing and are therefore not included in the evaluated configuration:\n o **Dormant Mode** - Although CA Top Secret is installed, it is not actively validating access. Checks are made for Administrators, but not for users.\n o **Warn Mode** – Warn mode is used to:\n ▪ Determine which users are accessing which resources\n ▪ Test the access definitions made in DORMANT mode\n\nWarn mode can be set by facility, profile, user, resource, or event.\n\nNote: Some applications make RACROUTE calls with the LOG=NOFAIL parameter. In WARN mode, these types of calls are written to the audit file if the check fails, but no message displays.\n\n ▪ **Signon Violations** - In WARN mode, define all users to CA Top Secret or CA Top Secret generates and records signon violations. WARN mode does not prevent an undefined user from signing on or gaining access to a protected resource.\n ▪ **Password Violations** - WARN mode does not prevent a defined user from signing on with an incorrect password, but this action generates a password violation.\n\nNote: To force a defined user to supply a correct password in WARN mode, the WARNPW sub-option of the FACILITY control option must be set. Administrators must always supply a correct password, even in DORMANT mode.\n\n ▪ **Resource Violations** - If default protection is given to specific resource classes by attaching the DEFPROT attribute, WARN mode generates violations for all defined resources.\n ▪ **Global Warn Mode** - Use Global WARN mode to test segments of the implementation, or to back off from FAIL mode when an implemented segment of the organization is in trouble.\n\n• **CA Mainframe Software Manager (MSM)** – The CA MSM is a utility used by the TOE that allows for the initial acquisition of CA Top Secret. This utility is part of the operational environment and provides no security enforcing functionality for the TOE once it has been acquired.\n\n2.4 **Physical Boundary**\n\nThe TOE includes the CA Top Secret components:\n- Operator Communications\n- System Authorization Facility (SAF)\n- Command Propagation Facility (CPF)\n\nThe following table illustrates the minimum requirements needed to install CA Top Secret on a z/OS system.\n\n<table>\n<thead>\n<tr>\n<th>Requirement</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Operating System</td>\n<td>Operating System: z/OS V1R9 or later OR The Customized Offerings Driver V3</td>\n</tr>\n<tr>\n<td>A TSO/E Session</td>\n<td>A TSO/E Session: A TSO/E Session on the IPLed system must be established using a locally-attached or network-attached terminal</td>\n</tr>\n<tr>\n<td>Proper Authority</td>\n<td>Proper Authority: Use the RACFDRV installation job as a sample of the security system definitions required so that a user can perform the installation tasks</td>\n</tr>\n</tbody>\n</table>\n| Proper Security | Proper Security: In order to install the z/OS UNIX files, the following is required: \n - The ACID must be a superuser (UID=0) or have read access to the BPX.SUPERUSER resource in the RACF FACILITY class. \n - The ACID must have read access to FACILITY class resources BPX.FILEATTR.APF, BPX.FILEATTR.PROGCTL, and BPX.FILEATTR.SHARELIB (or BPX.FILEATTR.* if a user chooses to use a generic name for these resources). The commands to define these FACILITY class resources are in SYS1.SAMPLIB member BPXISEC1. |\n| OMVS Address Space Active | OMVS Address Space Active: For ServerPac only (not SystemPac), an activated OMVS address space with z/OS UNIX kernel services operating in full function mode is required. |\n| SMS Active | SMS Active: The Storage Management Subsystem (SMS) must be active to allocate z/OS UNIX file systems (HFS or zFS) and PDSE data sets, whether they are SMS-managed or non-SMS-managed. In addition, the use of z/OS UNIX file systems (HFS or zFS) is supported only when SMS is active in at least a null configuration, even when the file systems are not SMS-managed. Do either of the following: \n - To allocate non-SMS-managed z/OS UNIX file systems (HFS or zFS) and PDSE data sets, a user must activate SMS on the driving system in at least a null configuration. A user must also activate SMS on the target system. \n - To allocate SMS-managed z/OS UNIX file systems (HFS or zFS) and PDSE data sets, a user must activate SMS on the driving system in at least a minimal configuration. Then a user must define a storage group, create SMS-managed volumes, and write, translate, and activate a storage class ACS routine that allows the allocation of z/OS UNIX file systems (HFS or zFS) and PDSE data sets with the names in the ALLOCDS job. A user must also activate SMS on the target system. |\n<p>| DFSORT | DFSORT: msys for Setup job XMLGNR8 requires DFSORT or an equivalent sort program on the system on which the XMLGNR8 job is run. |\n| Language Environment | Language Environment: The CustomPac Installation Dialog uses the Language Environment runtime library, SCEERUN. If SCEERUN is not in the link list on the driving system, a user must edit the ServerPac installation jobs to add it to the JOBLIB or STEPLIB DD statements. |</p>\n<table>\n<thead>\n<tr>\n<th>CustomPac Installation Dialog</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>If installing a ServerPac or dump-by-data-set SystemPac for the first time, a user will need to install the CustomPac Installation Dialog on the driving system. See <em>ServerPac: Using the Installation Dialog</em> or <em>SystemPac: CustomPac Dialog Reference</em> for instructions. For subsequent orders, a user will not need to reinstall the dialog. IBM ships dialog updates with each order. A user should check the PSP bucket for possible updates to the CustomPac Installation Dialog. For ServerPac, the upgrade is ZOSV1R11 and the subset is SERVERPAC. For SystemPac dump-by-data-set orders, the upgrade is CUSTOMPAC and the subset is SYSPAC/DBD.</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Proper Level for Service</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>In order for a user to install service on the target system that are building, a user’s driving system must minimally meet the driving system requirements for CBPDO Wave 1 and must have the current (latest) levels of the program management binder, SMP/E, and HLASM.</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>SMP/E ++JAR Support</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>If the ServerPac order contains any product that uses the ++JAR support introduced in SMP/E V3R2 (which is the SMP/E in z/OS V1R5), the driving system requires IBM SDK for z/OS, Java 2 Technology Edition, V1 (5655-I56) at SDK 1.4 or later. z/OS itself does not use the ++JAR support.</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>zFS Configured Properly</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>If using a zFS for installation, then a user must be sure that the zFS has been installed and configured, as described in <em>z/OS Distributed File Service zSeries File System Administration</em>.</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Internet Delivery Requirements</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>If intending to receive the ServerPac or SystemPac dump-by-data-set order by way of the Internet, a user will need the following:</td>\n</tr>\n<tr>\n<td>- SMP/E PTF UO00678 (APAR IO07810) if SMP/E level is V3R4 (which is in z/OS V1R7, V1R8, and V1R9). In ICSF configured and active so that it can calculate SHA-1 hash values in order to verify the integrity of data being transmitted. If ICSF is not configured and active, SMP/E calculates the SHA-1 hash values using an SMP/E Java application class, provided that IBM SDK for z/OS, Java 2 Technology Edition, V1 (5655-I56) or later is installed. IBM recommends the ICSF method because it is likely to perform better than the SMP/E method. (To find out how to configure and activate ICSF, see <em>z/OS Cryptographic Services ICSF System Programmer’s Guide</em>. For the required SMP/E setup, see <em>SMP/E User’s Guide</em>.</td>\n</tr>\n<tr>\n<td>- A download file system. The order is provided in a compressed format and is saved in a download file system. The size of this file system should be approximately twice the compressed size of the order to accommodate the order and workspace to process it. Firewall configuration. If the enterprise requires specific commands to allow the download of the order using FTP through a local firewall, a user must identify these commands for later use in the CustomPac Installation Dialog, which manages the download of the order.</td>\n</tr>\n<tr>\n<td>- Proper dialog level. If a user is using a CustomPac Installation Dialog whose Package Version is less than 17.00.00, he/she must migrate the dialog to this level or later. The user can</td>\n</tr>\n</tbody>\n</table>\nIf planning to download the ServerPac or SystemPac dump-by-data-set order to a workstation and from there to z/OS, a user will need the following in addition to the requirements listed in item 13 on page 56:\n\n- Download Director. This is a Java applet used to transfer IBM software to workstation.\n\n- The ServerPac or SystemPac dump-by-data-set order accessible to the host. To make the order (files) accessible to z/OS, can do either of the following:\n - Configure the workstation as an FTP server. After downloading the order to the workstation, the dialogs used to install a ServerPac or SystemPac dump-by-data-set order can point to a network location (in this case, workstation) to access the order. Consult the documentation for the workstation operating system to determine if this FTP capability is provided or if it has to install additional software. Commercial, shareware, and freeware applications are available to provide this support. However, IBM cannot directly recommend or endorse any specific application. This option requires the use of ICSF.\n\n - Use network drives that are mounted to z/OS. The mounting can be accomplished using the NFS base element, server message block (SMB) support provided by the Distributed File Service base element, or the Distributed FileManager component of the DFSMSdftp base element. The package is received from the file system defined as the SMPNTS.\n\n - CD write capability. If specified that 100% electronic delivery is required, there might be CD images associated with the order. The images are delivered in ISO9660 format and are packaged in zip files (with an extension of .zip). These files require the workstation to have CD write capability and might have to acquire software to support this capability.\n\nTable 2-3: Minimum OS Requirements for Installation of the TOE\n\nFor more information on the hardware requirements for z/OS, see the z/OS v1 r11 Planning for Installation Guide.\n\n2.5 Logical Boundary\n\nThe logical boundary of the TOE is described in the terms of the security functionalities that the TOE provides to the systems that utilize this product for information flow control.\nThe logical boundary of the TOE will be broken down into five security classes: Security Audit, Identification and Authentication, Security Management, User Data Protection, and TOE Access. Listed below are the security functions with a listing of the capabilities associated with them:\n\n### 2.5.1 Security Audit\n\nCA Top Secret uses the System Management Facility (SMF) to record all security-relevant events. These records are secured from accidental disclosure or destruction by the standard Discretionary Access Control (DAC) and Mandatory Access Control (MAC) protection mechanisms. The TOE enforces the Mandatory Access Control (MAC) policy to objects based on users, resources, and AccessLevel, Type, Object Security Label, and Subject Security label. The TOE enforces the Discretionary Access Control (DAC) policy to objects based on users, entity, security relevant attributes control option auth, resource class name, entity name, secrec, ownership, facility, time of day, day of week, sysid, Limited Command Facility (LCF), calendar, program, and library.\n\nCA Top Secret provides report utilities to produce reports. For example, the TSSUTIL utility report provides an audit trail of security events. A variety of parameters can be set to customize the reports.\n\n### 2.5.2 Identification & Authentication\n\nCA Top Secret controls how, when, and which resources a user can access. CA Top Secret requires that each end user have a valid accessor ID (ACID) and password before entering the system. An ACID can be up to eight alphanumeric characters long, which normally corresponds with the user’s system userid. The same ACID can be used for all facilities or a different ACID can be used for each facility (such as TSO, CICS, and z/VM).\n\nBy default, CA Top Secret requires that all ACIDs are password protected. A security administrator assigns the first password. The user associated with the ACID changes the password immediately (or later if they desire) when it expires. Password assignment is controlled by CA Top Secret; control option values are set and stored within CA Top Secret.\n\n### 2.5.3 Security Management\n\nThe TOE maintains three roles: security administrators, scoped security administrators and users. Administrators manage the TOE and its users; whereas a user’s primary function is to perform work. Any administrator with ACID (CREATE) administrative authority can establish users. While a user can be assigned most types of administrative authority, the user’s scope is always limited to itself.\n\nSecurity administrators can display and change fields of ACIDs based on their scope. Scoped administrators can perform administrative operations that are defined within their scope.\n2.5.4 User Data Protection\n\nCA Top Secret determines whether an individual user should be permitted access to a resource and must be able to associate a user’s identity with each job or time-sharing session. No job can run on a CA Top Secret-controlled system unless it can first be identified with a valid, predefined user. Thus, CA Top Secret is also protecting the resources of the computer system itself. No one can use processing time on a system unless they are running under an ACID previously defined to CA Top Secret.\n\nCA Top Secret performs two main methods of access control, one being mandatory access control (MAC) and the other being discretionary access control (DAC).\n\nMAC imposes a security policy based on security labels. Security labels classify users, data, and resources. Standard permissions still apply, but only after MAC label dominance checks determine that a user can access data and resources based on their security label and the security label of the data or resources the user wants to access.\n\nDAC security policy manages the controlled sharing of data and resources using permissions. Depending on an implementation option, a security administrator or data owner can write rules to permit sharing. If a user tries to access data without permission, the system creates a violation record and denies access.\n\n2.5.5 TOE Access\n\nCA Top Secret is capable of denying access to TOE users who have a suspended/canceled account or have failed to enter a correct password within the threshold limit set by an administrator.\n\nFor more information on TOE Access, see Section 9.1.5.\n3 Conformance Claims\n\n3.1 CC Version\n\n3.2 CC Part 2 Conformant\nThis ST and Target of Evaluation (TOE) is Part 2 conformant for EAL4 to include all applicable NIAP and International interpretations through 1 April 2011.\n\n3.3 CC Part 3 Conformant Plus Flaw Remediation\nThis ST and Target of Evaluation (TOE) is Part 3 conformant plus flaw remediation for EAL4 to include all applicable NIAP and International interpretations through 1 April 2011.\n\n3.4 PP Claims\nThis ST does not claim Protection Profile (PP) conformance.\n\n3.5 Package Claims\nThis TOE claims a package for EAL 4.\n\n3.6 Package Name Conformant or Package Name Augmented\nThis ST and Target of Evaluation (TOE) is conformant to EAL package claims augmented with ALC_FLR.1 and ASE_TSS.2.\n\n3.7 Conformance Claim Rationale\nThere is no Conformance Claim rationale for this ST.\n4 Security Problem Definition\n\n4.1 Threats\n\nThe TOE itself has threats and the TOE is also responsible for addressing threats to the environment in which it resides. The assumed level of expertise of the attacker for all the threats is unsophisticated. The following are threats addressed by the TOE.\n\nT.ACCESS Unauthorized users or administrators could gain access to objects protected by the TOE that they are not authorized to access.\n\nT.ADMIN_ERROR An administrator may incorrectly install or configure the TOE, or install a corrupted TOE resulting in ineffective security mechanisms.\n\nT.AUDIT_COMPROMISE A malicious user or process may view audit records, cause audit records to be lost or modified, or prevent future audit records from being recorded; thus masking a user’s action.\n\nT.MASK Users whether they be malicious or non-malicious, could gain unauthorized access to the TOE by bypassing identification and authentication countermeasures.\n\n4.2 Organizational Security Policies\n\nThere are no Organizational Security Policies that apply to the TOE.\n\n4.3 Secure Usage Assumptions\n\nThe specific conditions listed in this section are assumed to exist in the environment in which the TOE is deployed. These assumptions are necessary as a result of practical realities in the development of the TOE security requirements and the essential environmental conditions on the use of the TOE.\n\n4.3.1 Personnel Assumptions\n\nA.ADMIN One or more authorized administrators will be assigned to install, configure and manage the TOE and the security of the information it contains.\n\nA.PATCHES Administrators exercise due diligence to update the TOE with the latest patches and patch the Operational Environment (e.g., OS and database) so they are not susceptible to network attacks.\nA.NOEVIL Administrators of the TOE are not careless, wilfully negligent, or hostile and will follow and abide by the instructions provided by the organization’s guidance documentation.\n\n4.3.2 Connectivity Assumptions\nThere are no connectivity assumptions that apply to the TOE.\n\n4.3.3 Physical Assumptions\nA.LOCATE The TOE will be located within controlled access facilities that will prevent unauthorized physical access.\n5 Security Objectives\n\nThe following security objectives are to be satisfied by the TOE.\n\n5.1 Security Objectives for the TOE\n\nThe following security objectives are to be satisfied by the TOE.\n\n**O.ACCESS** The TOE will provide measures to authorize users and administrators to access objects protected by the TOE once they have been authenticated. User and administrator authorization is based on access rights configured by the administrators of the TOE.\n\n**O.AUDIT** The TOE will provide measures for recording security relevant events that will assist the authorized users and administrators in detecting misuse of the TOE and/or its security features that would compromise the integrity of the TOE and violate the security objectives of the TOE.\n\n**O.AUTH** The TOE will provide measures to uniquely identify all users and administrators. The TOE will authenticate the claimed identity prior to granting a user or administrator access to the objects protected by the.\n\n**O.MANAGE** The TOE will provide authorized administrators with the resources to manage and monitor user accounts, objects, and security information relative to the TOE.\n\n**O.ROBUST_ADMIN_GUIDANCE** The TOE will provide administrators with the necessary information for secure delivery and management.\n\n**O.ROBUST_TOE_ACCESS** The TOE will provide mechanisms that control a user’s and an administrator’s logical access to the TOE and to explicitly deny access to specific users and administrators when appropriate.\n\n5.2 Security Objectives for the operational environment of the TOE\n\nThe following security objectives for the Operational environment of the TOE must be satisfied in order for the TOE to fulfill its security objectives.\n\n**OE.ADMIN** One or more authorized administrators will be assigned to configure the Operational Environment, and install,\nconfigure and manage the TOE and the security of the information it contains.\n\n**OE.EAVESDROPPING**\nThe Operational Environment will encrypt TSF data when called by the TOE to prevent malicious users from gaining unauthorized access to TOE data.\n\n**OE.NOEVIL**\nAll administrators of the TOE are not careless, willfully negligent, or hostile and will follow and abide by the instructions provided by the organization’s user guidance documentation.\n\n**OE.LOCATE**\nThe TOE will be located within controlled access facilities that will prevent unauthorized physical access.\n\n**OE.SYSTIME**\nThe operating environment will provide reliable system time.\n6 Extended Security Functional and Assurance Requirements\n\n6.1 Extended Security Functional Requirements for the TOE\nThere are no extended Security Functional Requirements for this ST.\n\n6.2 Extended Security Assurance Requirements\nThere are no extended Security Assurance Requirements in this ST.\n# Security Functional Requirements\n\n## 7.1 Security Functional Requirements for the TOE\n\nThe following table provides a summary of the Security Functional Requirements implemented by the TOE.\n\n<table>\n<thead>\n<tr>\n<th>Security Function</th>\n<th>Security Functional Components</th>\n</tr>\n</thead>\n</table>\n| **Security Audit (FAU)**| FAU_GEN.1 Audit data generation \nFAU_GEN.2 User identity association \nFAU_SAR.1 Audit review \nFAU_SAR.2 Restricted audit review \nFAU_SEL.1 Selective audit |\n| **User Data Protection (FDP)** | FDP_ACC.2(1) Complete access control \nFDP_ACC.2(2) Complete access control \nFDP_ACF.1(1) Security attribute based access control \nFDP_ACF.1(2) Security attribute based access control |\n| **Identification and Authentication (FIA)** | FIA_AFL.1 Authentication failure handling \nFIA_ATD.1 User attribute definition \nFIA_SOS.1(1) Verification of secrets \nFIA_SOS.1(2) Verification of secrets \nFIA_SOS.2 TSF generation of secrets \nFIA_UAU.2 User authentication before any action \nFIA_UAU.4 Single-use authentication mechanisms \nFIA_UAU.5 Multiple authentication mechanisms \nFIA_UID.2 User identification before any action \nFIA_USB.1 User-subject binding |\n| **Security Management (FMT)** | FMT_MOF.1(1) Management of security functions behavior \nFMT_MOF.1(2) Management of security functions behavior \nFMT_MOF.1(3) Management of security functions behavior \nFMT_MOF.1(4) Management of security functions behavior \nFMT_MSA.1 Management of security attributes \nFMT_MSA.3 Static attribute initialization \nFMT_SMF.1 Specification of management functions \nFMT_SMR.1 Security roles |\n<table>\n<thead>\n<tr>\n<th>Security Function</th>\n<th>Security Functional Components</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>TOE Access (FTA)</td>\n<td>FTA_TSE.1 TOE session establishment</td>\n</tr>\n</tbody>\n</table>\n\nTable 7-1: Security Functional Requirements for the TOE\n\n### 7.1.1 Class FAU: Security Audit\n\n#### 7.1.1.1 FAU_GEN.1 Audit data generation\n\nHierarchical to: No other components.\n\n**FAU_GEN.1.1** The TSF shall be able to generate an audit record of the following auditable events:\n\na) Start-up and shutdown of the audit functions;\n\nb) All auditable events for the [not specified] level of audit; and\n\nc) [all auditable events between subjects and resources].\n\n**FAU_GEN.1.2** The TSF shall record within each audit record at least the following information:\n\na) Date and time of the event, type of event, subject identity, and the outcome (success or failure) of the event; and\n\nb) For each audit event type, based on the auditable event definitions of the functional components included in the PP/ST, [CPUID, Jobname, and Source].\n\nDependencies: FPT_STM.1 Reliable time stamps\n\n**Application Note:** The mode will always be FAIL in the evaluated configuration\n\n**Application Note:** All audit records are SMF type 80 records.\n\n**Application Note:** Auditable events are all events that a user (or an application on behalf of the user) generates, as well as events from the system that don’t have the parameter log=nofail. Only applications or systems can specify this parameter.\n7.1.1.2 FAU_GEN.2 User identity association\n\nHierarchical to: No other components.\n\nFAU_GEN.2.1 For audit events resulting from actions of identified users, the TSF shall be able to associate each auditable event with the identity of the user that caused the event.\n\nDependencies: FAU_GEN.1 Audit data generation\nFIA_ACID.1 Timing of identification\n\n7.1.1.3 FAU_SAR.1 Audit review\n\nHierarchical to: No other components.\n\nFAU_SAR.1.1 The TSF shall provide [authorized users with the acid(report) and resource(report) privileges] with the capability to read [all audit information collected by FAU_GEN.1 within their scope] from the audit records.\n\nFAU_SAR.1.2 The TSF shall provide the audit records in a manner suitable for the user to interpret the information.\n\nDependencies: FAU_GEN.1 Audit data generation\n\nApplication Note: All audit records are SMF type 80 records.\n\n7.1.1.4 FAU_SAR.2 Restricted audit review\n\nHierarchical to: No other components.\n\nFAU_SAR.2.1 The TSF shall prohibit all users read access to the audit records, except those users that have been granted explicit read-access.\n\nDependencies: FAU_SAR.1 Audit review\n\n7.1.1.5 FAU_SEL.1 Selective audit\n\nHierarchical to: No other components.\n\nFAU_SEL.1.1 The TSF shall be able to select the set of events to be audited from the set of all auditable events based on the following attributes:\n a) [Object identity, User identity]\nb) *Permission*\n\n**Dependencies:** FAU_GEN.1 Audit data generation\n\n**Application Note:** *Object identity is resource class and entity name and is captured by RACROUTE REQUEST=AUTH and FASTAUTH.*\n\n**Application Note:** *Auditing of violations on the TOE is automatic and cannot be turned off.*\n\n### 7.1.2 Class FDP: User Data Protection\n\n#### 7.1.2.1 FDP_ACC.2(1) Complete access control\n\n**Hierarchical to:** FDP_ACC.1 Subset access control\n\n**FDP_ACC.2.1 (1)** The TSF shall enforce the *Discretionary Access Control Policy* on *users and objects* and all operations among subjects and objects covered by the SFP.\n\n**FDP_ACC.2.2 (1)** The TSF shall ensure that all operations between any subject controlled by the TSF and any object controlled by the TSF are covered by an access control SFP.\n\n**Dependencies:** FDP_ACF.1 Security attribute based access control\n\n**Application Note:** *A user can refer to a user, an application issuing a RACROUTE call, a terminal command, or a console command. An object can be a data set, volume, command issued, etc. An example of an Access Level is an operation. For the list of all operations among subjects and objects, reference Table 7-2.*\n\n#### 7.1.2.2 FDP_ACC.2 (2) Complete access control\n\n**Hierarchical to:** FDP_ACC.1 Subset access control\nFDP_ACC.2.1 (2) The TSF shall enforce the [Mandatory Access Control Policy] on [users and objects] and all operations among subjects and objects covered by the SFP.\n\nFDP_ACC.2.2 (2) The TSF shall ensure that all operations between any subject controlled by the TSF and any object controlled by the TSF are covered by an access control SFP.\n\nDependencies: FDP_ACF.1 Security attribute based access control\n\n**Application Note:** The following table lists all operations allowed by TOE users:\n\n<table>\n<thead>\n<tr>\n<th>AccessLevel (DAC)</th>\n<th>DIRAUTHLevel (MAC)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Read</td>\n<td>Read</td>\n</tr>\n<tr>\n<td>Create</td>\n<td>Read</td>\n</tr>\n<tr>\n<td>Write</td>\n<td>Write</td>\n</tr>\n<tr>\n<td>Control</td>\n<td>ReadWrite</td>\n</tr>\n<tr>\n<td>Update</td>\n<td>ReadWrite</td>\n</tr>\n<tr>\n<td>Scratch</td>\n<td>ReadWrite</td>\n</tr>\n<tr>\n<td>Fetch</td>\n<td>ReadWrite</td>\n</tr>\n<tr>\n<td>Alter</td>\n<td>ReadWrite</td>\n</tr>\n</tbody>\n</table>\n\nTable 7-2: User Performed Operations on the TOE\n\n**Application Note:** The following list of classes is included in the evaluated configuration:\n\n<table>\n<thead>\n<tr>\n<th>Interface</th>\n<th>Resource Classes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Base CA Top Secret</td>\n<td>DATASET</td>\n</tr>\n<tr>\n<td>Secret products</td>\n<td>PROGRAM</td>\n</tr>\n<tr>\n<td>OPERCMDS</td>\n<td>SECLABEL</td>\n</tr>\n<tr>\n<td>TSOAUTH</td>\n<td>UNIXPRIV</td>\n</tr>\n<tr>\n<td>FACILITY</td>\n<td>IBMFAC</td>\n</tr>\n<tr>\n<td>CA Top Secret</td>\n<td>OTRAN</td>\n</tr>\n<tr>\n<td>CICS Interface</td>\n<td>TCICSTRN</td>\n</tr>\n<tr>\n<td></td>\n<td>FCT</td>\n</tr>\n<tr>\n<td></td>\n<td>PPT</td>\n</tr>\n<tr>\n<td>CA Top Secret</td>\n<td>CIMSS</td>\n</tr>\n<tr>\n<td>IMS Interface</td>\n<td>TIMS</td>\n</tr>\n<tr>\n<td></td>\n<td>IIMS</td>\n</tr>\n</tbody>\n</table>\n\nTable 7-3: Resource Classes Included in the Evaluated Configuration\n\n7.1.2.3 **FDP_ACF.1 (1) Security Attribute based access control**\n\nHierarchical to: No other components.\n\nFDP_ACF.1.1 (1) The TSF shall enforce the [Discretionary Access Control policy] to objects based on the following: [all operations between users and objects based upon the security attributes defined in Table 7-5, the objects defined by the\nresource classes listed in Table 7-3, resource class name, and entity name].\n\nFDP_ACF.1.2 (1) The TSF shall enforce the following rules to determine if an operation among controlled subjects and controlled objects is allowed: [the TOE will permit the requested operation to the protected object (i.e. entity), if the user has a matching secrecy entry that matches the class, partial entity name, facility, time of day, day of week, calendar (i.e. day of the year), sysid, program (and library) in the program path, and has an operation in that entry that dominates the requested operation. Furthermore, each secrecy that uses Limited Command Facility (LCF) will have an inclusion or exclusion list for the command issued. If that command is in the excluded list defined by LCF, the command will fail to execute. If the command was not on an inclusion list, the command will fail to execute].\n\nApplication Note: If the value of facility, time of day, day of week, calendar, sysid, library, program or LCF are not present, then no comparison is done for those attributes.\n\nFDP_ACF.1.3 (1) The TSF shall explicitly authorize access of subjects to objects based on the following additional rules: [a) If the ownership matches the user, then any operation is allowed by that user. b) If the parameter NOVOLCHK is set, then any operation is allowed for any volume c) If the parameter NODSNCHK is set, then any operation is allowed for any data set d) If the parameter NORESCHK is set, then any operation is allowed for any Resource. e) If the subject is APF authorized f) If Unix ACID is 0 (root)].\n\nFDP_ACF.1.4 (1) The TSF shall explicitly deny access of subjects to objects based on the [None].\n\nDependencies: FDP_ACC.1 Subset access control FMT_MSA.3 Static attribute initialization\n7.1.2.4 FDP_ACF.1 (2) Security attribute based access control\n\nHierarchical to: No other components.\n\nFDP_ACF.1.1 (2) The TSF shall enforce the [Mandatory Access Control] to objects based on the following: [all operations between users and objects based upon the security attributes, AccessLevel, Type, Object Security Label, and Subject Security label].\n\nFDP_ACF.1.2 (2) The TSF shall enforce the following rules to determine if an operation among controlled subjects and controlled objects is allowed: [the type of access is based on the values of TYPE and ACCESSLevel, as defined below:\n\n<table>\n<thead>\n<tr>\n<th>ACCESSLevel</th>\n<th>Type=MAC</th>\n<th>Type=EQUALMAC</th>\n<th>Type=RVRSMAC</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Read</td>\n<td>User Dominates</td>\n<td>Equivalence</td>\n<td>Resource Dominates</td>\n</tr>\n<tr>\n<td>Read/Write</td>\n<td>Equivalence</td>\n<td>Equivalence</td>\n<td>Equivalence</td>\n</tr>\n<tr>\n<td>Write</td>\n<td>Resource Dominates</td>\n<td>Equivalence</td>\n<td>User Dominates</td>\n</tr>\n</tbody>\n</table>\n\nTable 7-4: Mandatory Access Control\n\na) For Equivalence - if the security label on subject and object match, allow access\nb) For User Dominates - if security label on subject dominates object, allow access\nc) For Resource Dominates - if security label on the object dominates the user, allow access]\n\nFDP_ACF.1.3 (2) The TSF shall explicitly authorise access of subjects to objects based on the following additional rules: [None].\n\nFDP_ACF.1.4 (2) The TSF shall explicitly deny access of subjects to objects based on the [if the object has a security label and the subject does not].\n\nApplication Note: If the subject has a label and the object does not, access is allowed.\n\nApplication Note: Subjects are users or applications running on behalf of users, objects are entities grouped as resources. Type is a global access variable that determines what type of access control model to implement. (See table below in section 6.1.3.2) Objects are called entities in the TOE. The TOE reads the subject and object label, establishes dominance,\nand will allow access based on the AccessLevel requested and access control model type.\n\n7.1.3 Class FIA: Identification & Authentication\n\n7.1.3.1 FIA_AFL.1 Authentication Failure Handling\n\nHierarchical to: No other components\n\nFIA_AFL.1.1 The TSF shall detect when an administrator configurable positive integer within [0-254] unsuccessful authentication attempts occur related to all user login attempts.\n\nFIA_AFL.1.2 When the defined number of unsuccessful authentication attempts has been surpassed, the TSF shall suspend the user’s ACID.\n\nDependencies: FIA_UAU.1 Timing of authentication\n\nApplication Note: See the CA Top Secret Control Options Guide (PTHRESH).\n\nApplication Note: The authentication attempt counter cannot be set to zero as the threshold. The number increments from zero to the defined number (up to 254) and suspends the user once that threshold has been exceeded. A Security Administrator must then remove the suspension manually. This sets the value back to zero.\n\n7.1.3.2 FIA_ATD.1 User attribute definition\n\nHierarchical to: No other components.\n\nFIA_ATD.1.1 The TSF shall maintain the following list of security attributes belonging to individual users: [see Table 7-5 below]\n\n<table>\n<thead>\n<tr>\n<th>Role</th>\n<th>Attribute</th>\n<th>Specific Attribute</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>User and Scoped Security Administrator</td>\n<td>ACID</td>\n<td>Unique identifier per user (ACID)</td>\n</tr>\n<tr>\n<td></td>\n<td>Password</td>\n<td>User definable password</td>\n</tr>\n<tr>\n<td></td>\n<td>Passphrase</td>\n<td>User definable passphrase</td>\n</tr>\n<tr>\n<td></td>\n<td>Authentication Data</td>\n<td>Defines what type of authentication method is used per application (Kerberos, pass ticket, passphrase, password, certificate)</td>\n</tr>\n<tr>\n<td></td>\n<td>Profiles</td>\n<td>List of secrets for each user</td>\n</tr>\n<tr>\n<td></td>\n<td>Security Label</td>\n<td>Security labels classify users, data, and resources (MAC only)</td>\n</tr>\n</tbody>\n</table>\nProxy Records\n\nThe LDAPBIND PROXY USER profile record contains the information needed to connect to the LDAP server, including: BINDDN, BINDPW, LDAPHOST, DOMAINDN, LOCALREG, and ENABLE/DISABLE\n\nSource\n\nHow a user or administrator accesses the TOE (Terminal, facility)\n\nAppID\n\nApplication ID\n\nVendor Defined Fields\n\nUsers of the TOE can further define up to 32k worth of data that can be access control decisions. This only allows further restrictions to be defined for access.\n\nTime/Date\n\nTimes/DaysOfWeek user is allowed to log on to TOE.\n\nCERTDATA\n\nIdentifies the X.509 digital certificate(s) associated with the user/administrator\n\nSuspend\n\nIndicates whether the ACID is suspended, and the date this action was taken.\n\nSecurity Administrator\n\nACID\n\nUnique identifier per user (ACID)\n\nPassword\n\nUser definable password\n\nPassphrase\n\nUser definable passphrase\n\nAuthentication Data\n\n Defines what type of authentication method is used per application (Kerberos, pass ticket, passphrase, password, certificate)\n\nTable 7-5: CA Top Secret Generated User Security Attributes\n\nDependencies: No dependencies\n\nApplication Note: Authorizations can be in the user record, a profile (role), or the all record.\n\n7.1.3.3 FIA_SOS.1 (1) Verification of Secrets\n\nHierarchical to: No other components\n\nFIA_SOS.1.1 (1) The TSF shall provide a mechanism to verify that secrets meet [based on options selected by an administrator may include the following for passwords:\n\na) A password must always be set\nb) A configured minimum length of characters\nc) a minimum configurable number of numeric characters\nd) a minimum configurable number of uppercase letters\ne) a minimum configurable number of lowercase letters\nf) a configured limit of repeating characters\ng) Numbers cannot be the only characters used\nh) restrict the password to disallow restricted password prefixes\ni) Prevent a user from specifying a new password that contains his 8 byte username or first four bytes of his username\nj) Expiration date of password is a configurable number of days\nk) A requirement to disallow the new password of a user/administrator to match the previous configured number of passwords].\n\nDependencies: No dependencies\n\nApplication Note: See CA Top Secret Control Options Guide, NEWPW control option, for quality metrics.\n\n7.1.3.4 FIA_SOS.1 (2) Verification of Secrets\nHierarchical to: No other components\n\nFIA_SOS.1.1 (2) The TSF shall provide a mechanism to verify that secrets meet [ \n a. Minimum passphrase length is a configurable number of characters\n b. Expiration date of passphrase is a configurable number of days\n c. New passphrases cannot match a configured number of a user/administrator’s previous passphrases].\n\nDependencies: No dependencies\n\n7.1.3.5 FIA_SOS.2 TSF Generation of Secrets\nHierarchical to: No other components\n\nFIA_SOS.2.1 The TSF shall provide a mechanism to generate secrets that meet [see FIA_SOS.1.1 (1)].\nFIA_SOS.2.2 The TSF shall be able to enforce the use of TSF generated secrets for *password based authentication mechanisms*.\n\nDependencies: No dependencies\n\n### 7.1.3.6 FIA_UAU.2 User authentication before any action\n\nHierarchical to: FIA_UAU.1 Timing of authentication\n\nFIA_UAU.2.1 The TSF shall require each user to be successfully authenticated before allowing any other TSF-mediated actions on behalf of that user.\n\nDependencies: FIA_UID.1 Timing of identification\n\n*Application Note:* Without performing a Verify function, no other actions are allowed on the TOE. (i.e., if a user does not have a security context he does not have access, security context are built with the verify command).\n\n### 7.1.3.7 FIA_UAU.4 Single-use authentication mechanisms\n\nHierarchical to: No other components.\n\nFIA_UAU.4.1 The TSF shall prevent reuse of authentication data related to *passticket authentication*.\n\nDependencies: No dependencies\n\n*Application Note:* Passtickets are issued for a specific session and cannot be used again once that session has ended.\n\n### 7.1.3.8 FIA_UAU.5 Multiple authentication mechanisms\n\nHierarchical to: No other components\n\nFIA_UAU.5.1 The TSF shall provide *passwords, passtickets, Kerberos, digital certificates or passphrases* to support user authentication.\n\nFIA_UAU.5.2 The TSF shall authenticate any user's claimed identity according to the *application from which the user is requesting system entry*. \nDependencies: No dependencies\n\nApplication Note: The authentication method required for user authentication depends on the application from which the user is accessing the TOE.\n\nApplication Note: The authentication method does not allow for a user to select what they wish to enter as their credential. The mechanism for authentication is selected by the TOE and can be one of the five authentication mechanisms listed. The only occurrence where more than one mechanism is accepted is for TSO where both password and passphrase can be accepted.\n\n7.1.3.9 FIA_UID.2 User identification before any action\n\nHierarchical to: FIA_UID.1 Timing of identification\n\nFIA_UID.2.1 The TSF shall require each user to be successfully identified before allowing any other TSF-mediated actions on behalf of that user.\n\nDependencies: No dependencies\n\n7.1.3.10 FIA_USB.1 User-subject binding\n\nHierarchical to: No other components\n\nFIA_USB.1.1 The TSF shall associate the following user security attributes with subjects acting on the behalf of that user: [see Table 7-5].\n\nFIA_USB.1.2 The TSF shall enforce the following rules on the initial association of user security attributes with subjects acting on the behalf of users: [1. the TOE will create the user’s ACID 2. the TOE will create the user’s security environment].\n\nFIA_USB.1.3 The TSF shall enforce the following rules governing changes to the user security attributes associated with subjects acting on the behalf of users: [none].\n\nDependencies: FIA_ATD.1 User attribute definition\n7.1.4 Class FMT: Security Management\n\n7.1.4.1 FMT_MOF.1 (1) Management of security functions behavior\n\nHierarchical to: No other components\n\nFMT_MOF.1.1 (1) The TSF shall restrict the ability to [determine the behavior of, modify the behavior of] the functions [see Table 7-6] to [the Security Administrator].\n\nDependencies: FMT_SMR.1 Security roles\nFMT_SMF.1 Specification of Management Functions\n7.1.4.2 FMT_MOF.1 (2) Management of security functions behavior\n\nHierarchical to: No other components\n\nFMT_MOF.1.1 (2) The TSF shall restrict the ability to [determine the behavior of, modify the behavior of] the functions [see Table 7-6] to [the Scope Security Administrator according to their scope].\n\nDependencies: FMT_SMR.1 Security roles\n FMT_SMF.1 Specification of Management Functions\n\n7.1.4.3 FMT_MOF.1 (3) Management of security functions behavior\n\nHierarchical to: No other components.\n\nFMT_MOF.1.1 (3) The TSF shall restrict the ability to [determine the behavior of, modify the behavior of] the functions [self passwords and passphrases] to [users].\n\nDependencies: FMT_SMR.1 Security roles\n FMT_SMF.1 Specification of Management Functions\n\n7.1.4.4 FMT_MOF.1 (4) Management of security functions behavior\n\nHierarchical to: No other components.\n\nFMT_MOF.1.1 (4) The TSF shall restrict the ability to [determine the behavior of, modify the behavior of] the functions [see Table 7-6] to [users that own the object].\n\nDependencies: FMT_SMR.1 Security roles\n FMT_SMF.1 Specification of Management Functions\n\nApplication Note: Resource ownership implies that the owning ACID has an access level of ALL.\n\n<table>\n<thead>\n<tr>\n<th>Operation</th>\n<th>Administrative Functions</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Define</td>\n<td>Subject security attributes</td>\n</tr>\n<tr>\n<td>Change</td>\n<td>Subject security attributes</td>\n</tr>\n<tr>\n<td>Manage</td>\n<td>User identities</td>\n</tr>\n<tr>\n<td>Manage</td>\n<td>Authentication data by an administrator</td>\n</tr>\n<tr>\n<td>Control</td>\n<td>Authentication data that users are allowed to manage</td>\n</tr>\n<tr>\n<td>Manage</td>\n<td>User's own authentication data</td>\n</tr>\n<tr>\n<td>Manage</td>\n<td>Password policies</td>\n</tr>\n<tr>\n<td>Manage</td>\n<td>Threshold for unsuccessful authentication attempts</td>\n</tr>\n<tr>\n<td>--------</td>\n<td>---------------------------------------------------</td>\n</tr>\n<tr>\n<td>Manage</td>\n<td>Actions to be taken in the event of authentication failure</td>\n</tr>\n<tr>\n<td>Manage</td>\n<td>Attributes used to make explicit access or denial based decisions</td>\n</tr>\n<tr>\n<td>Manage</td>\n<td>Audit events</td>\n</tr>\n<tr>\n<td>Manage</td>\n<td>Groups with read access to the audit records</td>\n</tr>\n</tbody>\n</table>\n\nTable 7-6: Administrative Functions on the TOE\n\n7.1.4.5 FMT_MSA.1 Management of security attributes\n\nHierarchical to: No other components\n\nFMT_MSA.1.1 The TSF shall enforce the [the Mandatory Access Control and Discretionary Access Control policies] to restrict the ability to [modify, delete, manage, add, control, change] the security attributes [defined in Table 7-6] to [security administrators or scoped security administrators within their scope].\n\nDependencies: [FDP_ACC.1 Subset access control, or FDP_IFC.1 Subset information flow control] FMT_SMR.1 Security roles FMT_SMF.1 Specification of Management Functions\n\n7.1.4.6 FMT_MSA.3 Static attribute initialization\n\nHierarchical to: No other components.\n\nFMT_MSA.3.1 The TSF shall enforce the [Mandatory Access Control and Discretionary Access Control policies] to provide [restrictive] default values for security attributes that are used to enforce the SFP.\n\nFMT_MSA.3.2 The TSF shall allow the [security administrators or scoped security administrators within their scope] to specify alternative initial values to override the default values when an object or information is created.\n\nDependencies: FMT_MSA.1 Management of security attributes FMT_SMR.1 Security roles\n7.1.4.7 FMT_SMF.1 Specification of Management Functions\n\nHierarchical to: No other components\n\nFMT_SMF.1.1 The TSF shall be capable of performing the following management functions: [see Table 7-6].\n\nDependencies: No dependencies\n\n7.1.4.8 FMT_SMR.1 Security roles\n\nHierarchical to: No other components\n\nFMT_SMR.1.1 The TSF shall maintain the roles [security administrator, scoped security administrator, and user]\n\nFMT_SMR.1.2 The TSF shall be able to associate users with roles.\n\nDependencies: FIA_UID.1 Timing of identification\n\nApplication Note: The scoped security administrator includes the following: MSCA, SCA, ZCA, VCA, DCA, and LSCA. See section 9.1.4.1 for more information on the security administrators.\n\n7.1.5 Class FTA: TOE Access\n\n7.1.5.1 FTA_TSE.1 TOE session establishment\n\nHierarchical to: No other components\n\nFTA_TSE.1.1 The TSF shall be able to deny session establishment based on:\n\n1. The user’s status is suspended\n2. A policy which limits user access based on:\n a. Time/Date\n b. Source (terminal ID, IP address, POE)\n c. AppID (the application the user is trying to authenticate by).\n\nDependencies: No dependencies\n7.2 Operations Defined\n\nThe notation, formatting, and conventions used in this security target (ST) are consistent with version 3.1 of the Common Criteria for Information Technology Security Evaluation. All of the components in this ST are taken directly from Part 2 of the CC except the ones noted with “_EXT” in the component name. Font style and clarifying information conventions were developed to aid the reader.\n\nThe CC permits four functional component operations: assignment, iteration, selection, and refinement to be performed on functional requirements. These operations are defined in Common Criteria, Part 1 as:\n\n7.2.1 Assignments Made\n\nAn assignment allows the specification of parameters and is specified by the ST author in \\textit{italicized bold text}.\n\n7.2.2 Iterations Made\n\nAn iteration allows a component to be used more than once with varying operations and is identified with the iteration number within parentheses after the short family name, e.g. FAU\\_GEN.1 (1), FAU\\_GEN.1 (2).\n\n7.2.3 Selections Made\n\nA selection allows the specification of one or more items from a list and is specified by the ST author in \\textbf{bold text}.\n\n7.2.4 Refinements Made\n\nA refinement allows the addition of details and is identified with “Refinement:” right after the short name. The old text is shown with a strikethrough and \\textit{the new text is specified by italicized bold and underlined text}. \n8 Security Assurance Requirements\n\nThis section identifies the Security Assurance Requirement components met by the TOE. These assurance components meet the requirements for EAL4 augmented with ALC_FLR.1 and ASE_TSS.2.\n\n8.1 Security Architecture\n\n8.1.1 Security Architecture Description (ADV_ARC.1)\n\nADV_ARC.1.1D: The developer shall design and implement the TOE so that the security features of the TSF cannot be bypassed.\n\nADV_ARC.1.2D: The developer shall design and implement the TSF so that it is able to protect itself from tampering by un-trusted active entities.\n\nADV_ARC.1.3D: The developer shall provide a security architecture description of the TSF.\n\nADV_ARC.1.1C: The security architecture description shall be at a level of detail commensurate with the description of the SFR-enforcing abstractions described in the TOE design document.\n\nADV_ARC.1.2C: The security architecture description shall describe the security domains maintained by the TSF consistently with the SFRs.\n\nADV_ARC.1.3C: The security architecture description shall describe how the TSF initialization process is secure.\n\nADV_ARC.1.4C: The security architecture description shall demonstrate that the TSF protects itself from tampering.\n\nADV_ARC.1.5C: The security architecture description shall demonstrate that the TSF prevents bypass of the SFR-enforcing functionality.\n\nADV_ARC.1.1E: The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.1.2 Functional Specification with Complete Summary (ADV_FSP.4)\n\nADV_FSP.4.1D The developer shall provide a functional specification.\n\nADV_FSP.4.2D The developer shall provide a tracing from the functional specification to the SFRs.\n\nADV_FSP.4.1C The functional specification shall completely represent the TSF.\nADV_FSP.4.2C The functional specification shall describe the purpose and method of use for all TSFI.\n\nADV_FSP.4.3C The functional specification shall identify and describe all parameters associated with each TSFI.\n\nADV_FSP.4.4C The functional specification shall describe all actions associated with each TSFI.\n\nADV_FSP.4.5C The functional specification shall describe all direct error messages that may result from an invocation of each TSFI.\n\nADV_FSP.4.6C The tracing shall demonstrate that the SFRs trace to TSFIs in the functional specification.\n\nADV_FSP.4.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\nADV_FSP.4.2E The evaluator shall determine that the functional specification is an accurate and complete instantiation of the SFRs.\n\n8.1.3 Implementation Representation of the TSF (ADV_IMP.1)\n\nADV_IMP.1.1D The developer shall make available the implementation representation for the entire TSF.\n\nADV_IMP.1.2D The developer shall provide a mapping between the TOE design description and the sample of the implementation representation. Content and presentation elements:\n\nADV_IMP.1.1C The implementation representation shall define the TSF to a level of detail such that the TSF can be generated without further design decisions.\n\nADV_IMP.1.2C The implementation representation shall be in the form used by the development personnel.\n\nADV_IMP.1.3C The mapping between the TOE design description and the sample of the implementation representation shall demonstrate their correspondence. Evaluator action elements:\n\nADV_IMP.1.1E The evaluator shall confirm that, for the selected sample of the implementation representation, the information provided meets all requirements for content and presentation of evidence.\n8.1.4 Architectural Design (ADV_TDS.3)\n\nADV_TDS.3.1D The developer shall provide the design of the TOE.\n\nADV_TDS.3.2D The developer shall provide a mapping from the TSFI of the functional specification to the lowest level of decomposition available in the TOE design.\n\nADV_TDS.3.1C The design shall describe the structure of the TOE in terms of subsystems.\n\nADV_TDS.3.2C The design shall describe the TSF in terms of modules.\n\nADV_TDS.3.3C The design shall identify all subsystems of the TSF.\n\nADV_TDS.3.4C The design shall provide a description of each subsystem of the TSF.\n\nADV_TDS.3.5C The design shall provide a description of the interactions among all subsystems of the TSF.\n\nADV_TDS.3.6C The design shall provide a mapping from the subsystems of the TSF to the modules of the TSF.\n\nADV_TDS.3.7C The design shall describe each SFR-enforcing module in terms of its purpose and interaction with other modules.\n\nADV_TDS.3.8C The design shall describe each SFR-enforcing module in terms of its SFR-related interfaces, return values from those interfaces, interaction with and called interfaces to other modules.\n\nADV_TDS.3.9C The design shall describe each SFR-supporting or SFR-non-interfering module in terms of its purpose and interaction with other modules.\n\nADV_TDS.3.10C The mapping shall demonstrate that all behavior described in the TOE design is mapped to the TSFIs that invoke it.\n\nADV_TDS.3.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\nADV_TDS.3.2E The evaluator shall determine that the design is an accurate and complete instantiation of all security functional requirements.\n8.2 Guidance Documents\n\n8.2.1 Operational User Guidance (AGD_OPE.1)\n\nAGD_OPE.1.1D The developer shall provide operational user guidance.\n\nAGD_OPE.1.1C The operational user guidance shall describe, for each user role, the user-accessible functions and privileges that should be controlled in a secure processing environment, including appropriate warnings.\n\nAGD_OPE.1.2C The operational user guidance shall describe, for each user role, how to use the available interfaces provided by the TOE in a secure manner.\n\nAGD_OPE.1.3C The operational user guidance shall describe, for each user role, the available functions and interfaces, in particular all security parameters under the control of the user, indicating secure values as appropriate.\n\nAGD_OPE.1.4C The operational user guidance shall, for each user role, clearly present each type of security-relevant event relative to the user-accessible functions that need to be performed, including changing the security characteristics of entities under the control of the TSF.\n\nAGD_OPE.1.5C The operational user guidance shall identify all possible modes of operation of the TOE (including operation following failure or operational error), their consequences and implications for maintaining secure operation.\n\nAGD_OPE.1.6C The operational user guidance shall, for each user role, describe the security measures to be followed in order to fulfill the security objectives for the operational environment as described in the ST.\n\nAGD_OPE.1.7C The operational user guidance shall be clear and reasonable.\n\nAGD_OPE.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.2.2 Preparative Procedures (AGD_PRE.1)\n\nAGD_PRE.1.1D The developer shall provide the TOE including its preparative procedures.\nAGD_PRE.1.1C The preparative procedures shall describe all the steps necessary for secure acceptance of the delivered TOE in accordance with the developer's delivery procedures.\n\nAGD_PRE.1.2C The preparative procedures shall describe all the steps necessary for secure installation of the TOE and for the secure preparation of the operational environment in accordance with the security objectives for the operational environment as described in the ST.\n\nAGD_PRE.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\nAGD_PRE.1.2E The evaluator shall apply the preparative procedures to confirm that the TOE can be prepared securely for operation.\n\n8.3 Lifecycle Support\n\n8.3.1 Authorization Controls (ALC_CMC.4)\n\nALC_CMC.4.1D The developer shall provide the TOE and a reference for the TOE.\n\nALC_CMC.4.2D The developer shall provide the CM documentation.\n\nALC_CMC.4.3D The developer shall use a CM system.\n\nALC_CMC.4.1C The TOE shall be labeled with its unique reference.\n\nALC_CMC.4.2C The CM documentation shall describe the method used to uniquely identify the configuration items.\n\nALC_CMC.4.3C The CM system shall uniquely identify all configuration items.\n\nALC_CMC.4.4C The CM system shall provide automated measures such that only authorized changes are made to the configuration items.\n\nALC_CMC.4.5C The CM system shall support the production of the TOE by automated means.\n\nALC_CMC.4.6C The CM documentation shall include a CM plan.\n\nALC_CMC.4.7C The CM plan shall describe how the CM system is used for the development of the TOE.\n\nALC_CMC.4.8C The CM plan shall describe the procedures used to accept modified or newly created configuration items as part of the TOE.\nALC_CMC.4.9C The evidence shall demonstrate that all configuration items are being maintained under the CM system.\n\nALC_CMC.4.10C The evidence shall demonstrate that the CM system is being operated in accordance with the CM plan.\n\nALC_CMC.4.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.3.2 CM Scope (ALC_CMS.4)\n\nALC_CMS.4.1D The developer shall provide a configuration list for the TOE.\n\nALC_CMS.4.1C The configuration list shall include the following: the TOE itself; the evaluation evidence required by the SARs; the parts that comprise the TOE; the implementation representation; and security flaw reports and resolution status.\n\nALC_CMS.4.2C The configuration list shall uniquely identify the configuration items.\n\nALC_CMS.4.3C For each TSF relevant configuration item, the configuration list shall indicate the developer of the item.\n\nALC_CMS.4.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.3.3 Delivery Procedures (ALC_DEL.1)\n\nALC_DEL.1.1D The developer shall document procedures for delivery of the TOE or parts of it to the consumer.\n\nALC_DEL.1.2D The developer shall use the delivery procedures.\n\nALC_DEL.1.1C The delivery documentation shall describe all procedures that are necessary to maintain security when distributing versions of the TOE to the consumer.\n\nALC_DEL.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.3.4 Identification of Security Measures (ALC_DVS.1)\n\nALC_DVS.1.1D The developer shall produce development security documentation.\nALC_DVS.1.1C The development security documentation shall describe all the physical, procedural, personnel, and other security measures that are necessary to protect the confidentiality and integrity of the TOE design and implementation in its development environment.\n\nALC_DVS.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\nALC_DVS.1.2E The evaluator shall confirm that the security measures are being applied.\n\n**8.3.5 Life-cycle Definition (ALC_LCD.1)**\n\nALC_LCD.1.1D The developer shall establish a life-cycle model to be used in the development and maintenance of the TOE.\n\nALC_LCD.1.2D The developer shall provide life-cycle definition documentation.\n\nALC_LCD.1.1C The life-cycle definition documentation shall describe the model used to develop and maintain the TOE.\n\nALC_LCD.1.2C The life-cycle model shall provide for the necessary control over the development and maintenance of the TOE.\n\nALC_LCD.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n**8.3.6 Tools and techniques (ALC_TAT.1)**\n\nALC_TAT.1.1D The developer shall identify each development tool being used for the TOE.\n\nALC_TAT.1.2D The developer shall document the selected implementation-dependent options of each development tool.\n\nALC_TAT.1.1C Each development tool used for implementation shall be well defined.\n\nALC_TAT.1.2C The documentation of each development tool shall unambiguously define the meaning of all statements as well as all conventions and directives used in the implementation.\n\nALC_TAT.1.3C The documentation of each development tool shall unambiguously define the meaning of all implementation-dependent options.\n8.3.7 Flaw reporting procedures (ALC_FLR.1)\n\nALC_FLR.1.1D The developer shall document flaw remediation procedures addressed to TOE developers.\n\nALC_FLR.1.1C The flaw remediation procedures documentation shall describe the procedures used to track all reported security flaws in each release of the TOE.\n\nALC_FLR.1.2C The flaw remediation procedures shall require that a description of the nature and effect of each security flaw be provided, as well as the status of finding a correction to that flaw.\n\nALC_FLR.1.3C The flaw remediation procedures shall require that corrective actions be identified for each of the security flaws.\n\nALC_FLR.1.4C The flaw remediation procedures documentation shall describe the methods used to provide flaw information, corrections and guidance on corrective actions to TOE users.\n\nALC_FLR.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.4 Security Target Evaluation\n\n8.4.1 Conformance Claims (ASE_CCL.1)\n\nASE_CCL.1.1D The developer shall provide a conformance claim.\n\nASE_CCL.1.2D The developer shall provide a conformance claim rationale.\n\nASE_CCL.1.1C The conformance claim shall contain a CC conformance claim that identifies the version of the CC to which the ST and the TOE claim conformance.\n\nASE_CCL.1.2C The CC conformance claim shall describe the conformance of the ST to CC Part 2 as either CC Part 2 conformant or CC Part 2 extended.\nASE_CCL.1.3C The CC conformance claim shall describe the conformance of the ST to CC Part 3 as either CC Part 3 conformant or CC Part 3 extended.\n\nASE_CCL.1.4C The CC conformance claim shall be consistent with the extended components definition.\n\nASE_CCL.1.5C The conformance claim shall identify all PPs and security requirement packages to which the ST claims conformance.\n\nASE_CCL.1.6C The conformance claim shall describe any conformance of the ST to a package as either package-conformant or package-augmented.\n\nASE_CCL.1.7C The conformance claim rationale shall demonstrate that the TOE type is consistent with the TOE type in the PPs for which conformance is being claimed.\n\nASE_CCL.1.8C The conformance claim rationale shall demonstrate that the statement of the security problem definition is consistent with the statement of the security problem definition in the PPs for which conformance is being claimed.\n\n8.4.2 Extended Components Definition (ASE_ECD.1)\n\nASE_ECD.1.1D The developer shall provide a statement of security requirements.\n\nASE_ECD.1.2D The developer shall provide an extended components definition.\n\nASE_ECD.1.1C The statement of security requirements shall identify all extended security requirements.\n\nASE_ECD.1.2C The extended components definition shall define an extended component for each extended security requirement.\n\nASE_ECD.1.3C The extended components definition shall describe how each extended component is related to the existing CC components, families, and classes.\n\nASE_ECD.1.4C The extended components definition shall use the existing CC components, families, classes, and methodology as a model for presentation.\n\nASE_ECD.1.5C The extended components shall consist of measurable and objective elements such that conformance or nonconformance to these elements can be demonstrated.\nASE_ECD.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\nASE_ECD.1.2E The evaluator shall confirm that no extended component can be clearly expressed using existing components.\n\n**8.4.3 ST Introduction (ASE_INT.1)**\n\nASE_INT.1.1D The developer shall provide an ST introduction.\n\nASE_INT.1.1C The ST introduction shall contain an ST reference, a TOE reference, a TOE overview and a TOE description.\n\nASE_INT.1.2C The ST reference shall uniquely identify the ST.\n\nASE_INT.1.3C The TOE reference shall identify the TOE.\n\nASE_INT.1.4C The TOE overview shall summarize the usage and major security features of the TOE.\n\nASE_INT.1.5C The TOE overview shall identify the TOE type.\n\nASE_INT.1.6C The TOE overview shall identify any non-TOE hardware/software/firmware required by the TOE.\n\nASE_INT.1.7C The TOE description shall describe the physical scope of the TOE.\n\nASE_INT.1.8C The TOE description shall describe the logical scope of the TOE.\n\nASE_INT.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\nASE_INT.1.2E The evaluator shall confirm that the TOE reference, the TOE overview, and the TOE description are consistent with each other.\n\n**8.4.4 Security Objectives (ASE_OBJC.2)**\n\nASE_OBJC.2.1D The developer shall provide a statement of security objectives.\n\nASE_OBJC.2.2D The developer shall provide a security objectives rationale.\n\nASE_OBJC.2.1C The statement of security objectives shall describe the security objectives for the TOE and the security objectives for the operational environment.\nASE_OBJ.2.2C The security objectives rationale shall trace each security objective for the TOE back to threats countered by that security objective and OSPs enforced by that security objective.\n\nASE_OBJ.2.3C The security objectives rationale shall trace each security objective for the operational environment back to threats countered by that security objective, OSPs enforced by that security objective, and assumptions upheld by that security objective.\n\nASE_OBJ.2.4C The security objectives rationale shall demonstrate that the security objectives counter all threats.\n\nASE_OBJ.2.5C The security objectives rationale shall demonstrate that the security objectives enforce all OSPs.\n\nASE_OBJ.2.6C The security objectives rationale shall demonstrate that the security objectives for the operational environment uphold all assumptions.\n\nASE_OBJ.2.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.4.5 Security Requirements (ASE_REQ.2)\n\nASE_REQ.2.1D The developer shall provide a statement of security requirements.\n\nASE_REQ.2.2D The developer shall provide a security requirements rationale.\n\nASE_REQ.2.1C The statement of security requirements shall describe the SFRs and the SARs.\n\nASE_REQ.2.2C All subjects, objects, operations, security attributes, external entities and other terms that are used in the SFRs and the SARs shall be defined.\n\nASE_REQ.2.3C The statement of security requirements shall identify all operations on the security requirements.\n\nASE_REQ.2.4C All operations shall be performed correctly.\n\nASE_REQ.2.5C Each dependency of the security requirements shall either be satisfied, or the security requirements rationale shall justify the dependency not being satisfied.\n\nASE_REQ.2.6C The security requirements rationale shall trace each SFR back to the security objectives for the TOE.\nASE_REQ.2.7C The security requirements rationale shall demonstrate that the SFRs meet all security objectives for the TOE.\n\nASE_REQ.2.8C The security requirements rationale shall explain why the SARs were chosen.\n\nASE_REQ.2.9C The statement of security requirements shall be internally consistent.\n\nASE_REQ.2.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.4.6 **Security Problem Definition (ASE_SPD.1)**\n\nASE_SPD.1.1D The developer shall provide a security problem definition.\n\nASE_SPD.1.1C The security problem definition shall describe the threats.\n\nASE_SPD.1.2C All threats shall be described in terms of a threat agent, an asset, and an adverse action.\n\nASE_SPD.1.3C The security problem definition shall describe the OSPs.\n\nASE_SPD.1.4C The security problem definition shall describe the assumptions about the operational environment of the TOE.\n\nASE_SPD.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.4.7 **TOE Summary Specification (ASE_TSS.2)**\n\nASE_TSS.2.1D The developer shall provide a TOE summary specification.\n\nASE_TSS.2.1C The TOE summary specification shall describe how the TOE meets each SFR.\n\nASE_TSS.2.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\nASE_TSS.2.2C The TOE summary specification shall describe how the TOE protects itself against interference and logical tampering.\n\nASE_TSS.2.2E The evaluator shall confirm that the TOE summary specification is consistent with the TOE overview and the TOE description.\nASE_TSS.2.3C The TOE summary specification shall describe how the TOE protects itself against bypass.\n\n8.5 Tests\n\n8.5.1 Analysis of Coverage (ATE_COV.2)\n\nATE_COV.2.1D The developer shall provide an analysis of the test coverage.\n\nATE_COV.2.1C The analysis of the test coverage shall demonstrate the correspondence between the tests in the test documentation and the TSFIs in the functional specification.\n\nATE_COV.2.2C The analysis of the test coverage shall demonstrate that all TSFIs in the functional specification have been tested.\n\nATE_COV.2.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.5.2 Basic Design (ATE_DPT.2)\n\nATE_DPT.2.1D The developer shall provide the analysis of the depth of testing.\n\nATE_DPT.2.1C The analysis of the depth of testing shall demonstrate the correspondence between the tests in the test documentation and the TSF subsystems and SFR-enforcing modules in the TOE design.\n\nATE_DPT.2.2C The analysis of the depth of testing shall demonstrate that all TSF subsystems in the TOE design have been tested.\n\nATE_DPT.2.3C The analysis of the depth of testing shall demonstrate that the SFR-enforcing modules in the TOE design have been tested.\n\nATE_DPT.2.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.5.3 Functional Tests (ATE_FUN.1)\n\nATE_FUN.1.1D The developer shall test the TSF and document the results.\n\nATE_FUN.1.2D The developer shall provide test documentation\n\nATE_FUN.1.1C The test documentation shall consist of test plans, expected test results and actual test results.\nATE_FUN.1.2C The test plans shall identify the tests to be performed and describe the scenarios for performing each test. These scenarios shall include any ordering dependencies on the results of other tests.\n\nATE_FUN.1.3C The expected test results shall show the anticipated outputs from a successful execution of the tests.\n\nATE_FUN.1.4C The actual test results shall be consistent with the expected test results.\n\nATE_FUN.1.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\n8.5.4 Independent Testing (ATE_IND.2)\n\nATE_IND.2.1D The developer shall provide the TOE for testing.\n\nATE_IND.2.1C The TOE shall be suitable for testing.\n\nATE_IND.2.2C The developer shall provide an equivalent set of resources to those that were used in the developer's functional testing of the TSF.\n\nATE_IND.2.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\nATE_IND.2.2E The evaluator shall execute a sample of tests in the test documentation to verify the developer test results.\n\nATE_IND.2.3E The evaluator shall test a subset of the TSF to confirm that the TSF operates as specified.\n\n8.6 Vulnerability Assessment\n\n8.6.1 Vulnerability Analysis (AVA_VAN.3)\n\nAVA_VAN.3.1D The developer shall provide the TOE for testing.\n\nAVA_VAN.3.1C The TOE shall be suitable for testing.\n\nAVA_VAN.3.1E The evaluator shall confirm that the information provided meets all requirements for content and presentation of evidence.\n\nAVA_VAN.3.2E The evaluator shall perform a search of public domain sources to identify potential vulnerabilities in the TOE.\nAVA_VAN.3.3E The evaluator shall perform an independent vulnerability analysis of the TOE using the guidance documentation, functional specification, TOE design, security architecture description and implementation representation to identify potential vulnerabilities in the TOE.\n\nAVA_VAN.3.4E The evaluator shall conduct penetration testing, based on the identified potential vulnerabilities, to determine that the TOE is resistant to attacks performed by an attacker possessing Enhanced-Basic attack potential.\n9 TOE Summary Specification\n\n9.1 TOE Security Functions\n\nThe following sections identify the security functions of the TOE. They include Security Audit, Identification and Authentication, User Data Protection, Security Management, and TOE Access.\n\n9.1.1 Security Audit\n\nCA Top Secret provides numerous report generators to create various reports for audit trail purposes. Any attempted violation CA Top Secret detects appears within a report. In addition, standard reports display each update to the CA Top Secret security file. Thus, any addition, change, or deletion of any of CA Top Secret user or permission information is visible to a person reviewing these reports. Records produced from Recovery file provide information presented in the CA Top Secret Audit Changes reports. Other reports are also available to record occurrences or produce audit trails of authorized activities. These are of various types. A user can produce each type independently of the others. They are explained in the following sections.\n\nThrough hierarchal scope an administrator can be restricted to only certain user records. CA Top Secret enforces the existing permissions for any other type of access.\n\n9.1.1.1 Security & Audit Privileges\n\nThe TSSAUDIT utility lets authorized users with the appropriate privileges monitor changes to the Security File, sensitive facilities, and data areas. An authorized user with the audit privilege has the authority to audit the following:\n\n- **Users** - The Administrator attaches the AUDIT attribute to the user's ACID.\n- **Resources** - The Administrator updates the AUDIT record with the resource or resource prefix (up to 64 characters) and optional access levels to be audited.\n- **A Specific Permission** - The Administrator includes the ACTION (AUDIT) keyword on the PERMIT command function.\n\n9.1.1.2 Audit/Tracking File\n\nBy default, CA Top Secret logs all violations to the System Management Facility (SMF). The Audit/Tracking file is also available for logging violations and audited events. The Audit/Tracking file lets administrators:\n\n- Eliminate SMF logging for violations and activity\n- Configure so that logging to the Audit/Tracking file cannot be suppressed. This configuration eliminates a potential security exposure\n- Generate reports for up-to-the-minute information\n- Extract security events that are logged to produce reports using the TSSUTIL batch utility\nTSSUTIL can be used to routinely archive audit-tracking information. CA Top Secret allows the online, real-time display of selected security activity on TSO and CICS terminals with the TSSTRACK utility. The TSSTRACK online tracking capability can only be used if the Audit/Tracking file is used. TSSAUDIT permits auditors to monitor changes to the security file and sensitive z/OS facilities and data areas.\n\nWhenever an option is changed, the TOE automatically maintains an audit trail, including the ACID that changed the control option.\n\n### 9.1.1.3 Violations and Logging\n\nThe LOG control option is the primary mechanism that controls the reporting of system activity and violations for all facilities. The LOG sub-option of the FACILITY control option can also be used to control individual facilities. Among the options for tracking security breaches are:\n\n- A violation generates a descriptive message sent to the security console, the user's online terminal, or both.\n- Job/session initiations and terminations, resource accesses, security violations, or any combination of these events are logged for all or selected facilities.\n- A record of selected types of events is logged to SMF, the Audit/Tracking file, or both. The Audit/Tracking File can be shared across CPUs, providing a single reference source for security events.\n\nWhen ACTION (AUDIT) is used with the PERMIT command function, it audits all accesses to the specified resource regardless of the mode or logging options of the user.\n\nIn FAIL mode, messages are issued regardless of the LOG control option specifications. The logging of activity is transparent to the user. The format logged is an SMF type-80 format.\n\n### 9.1.1.4 Security Event Logging\n\nCA Top Secret provides the following batch utility programs to help monitor and control system security, log system activity, and perform disaster recovery.\n\n#### 9.1.1.4.1 TSSAUDIT\n\nThis batch utility is run in order to monitor changes to the security file and sensitive facilities and data areas. It can be used to list:\n• ACIDs that possess administrative or special privileges (such as AUDIT, CONSOLE) or any of the security bypass attributes\n\n• The changes made to the security file. TSSAUDIT generates this information for a given date or time span by examining the recovery file. All changes made by a particular ACID can also be requested. The ACID must fall within the scope of the administrator running TSSAUDIT\n\n• Information about modules in APF-authorized libraries\n\n• Information about site-written (non-IBM) SVCs, the Program Properties Table (PPT), and the Terminal Monitor Program's (TMP) authorized program lists\n\n• The last two capabilities are especially useful for pinpointing security weaknesses\n\n9.1.1.4.2 TSS CPR\n\nThis utility is run against the CPF recovery file to produce a flat file record. This record can then be filtered through the TSSREPORT3 EARL Report option or through another report writer to depict the contents of the CPF recovery file.\n\n9.1.1.4.3 TSSOERPT\n\nThis batch utility program is run to process security-related activity recorded in SMF data sets. To monitor user activity in an OpenEdition MVS environment, CA Top Secret logs security events under OpenEdition MVS to SMF using the standard CA Top Secret SMF record. Log records are written for any security event that denies the ACID access to an OpenEdition MVS facility. These records can assist administrators in determining the UID and GID of the ACID involved in the attempted access.\n\n9.1.1.4.4 TSS PROT\n\nThis utility is run to determine which of these data sets have and do not have their security bit indicators turned on. The TSS PROT utility pertains to VSAM and non-VSAM data sets in an SU32 environment. Administrators can also use TSS PROT to turn security bits on or off for specific data sets or all data set located on accessible volumes.\n\nNote: Only the MSCA or an SCA can use this utility.\n\n9.1.1.4.5 TSS RECVR\n\nThis utility is run to aid recovery from loss or corruption of the security file. During normal system operation, the TOE maintains a record of all changes to the security file in the recovery file, which is a perpetual file. Changes are recorded to the file in a wraparound format. Therefore, this file must be large enough to accommodate all changes that occur between security file backups.\n9.1.1.4.6 TSSRPTST\nThis batch utility program is run to process and display the output that the SAF SECTRACE command sends to SMF. To run the TSSRPTST report, administrators must have already run the SAF SECTRACE operator command and set the output destination to SMF. With few exceptions, the TOE processes all z/OS SAF security requests by default. The SAF Trace report displays the monitored RACROUTE parameter list passed by requests for SAF services. This report also displays additional environmental information, such as job name, ACID, and the program issuing the SAF call.\n\n9.1.1.4.7 TSSTRACK\nThis utility is used to monitor security-related events from an online terminal in a real-time manner. This functionality lets the security administrator monitor suspicious activity \"as it happens.\" Furthermore, TSSTRACK enables all CPUs on a single security audit file to be monitored from a single terminal. TSSTRACK can go back to a specified date to focus on a selected facility or on violations only.\n\nThe events that security administrators can monitor using TSSTRACK are limited by their administrative scope. All the information that TSSTRACK displays is obtained from the CA Top Secret Audit/Tracking file; only information logged to this file can be monitored.\n\n9.1.1.5 Security Reports\nCA Top Secret provides the following batch utilities to translate resource access attempts and security events into reports, as stated in the following descriptions.\n\n9.1.1.5.1 TSSCHART\nTSSCHART is a batch utility that provides an overview of the security file architecture by generating block charts of ACIDs/owned-resource relationships. This functionality lets administrators examine the security hierarchy \"at-a-glance.\" Scope restrictions are honored so that if a properly authorized DCA uses the TSSCHART utility, the block chart the DCA receives only illustrates the ACIDs and resource relationships within the DCA's department. To view the installation as a whole, the MSCA or a properly authorized SCA must run the utility.\n\n9.1.1.5.2 TSSUTIL\nTSSUTIL is a flexible report generator/extract utility that provides batch reports of any security-related events logged to the Audit/Tracking File and/or SMF. Selection criteria for TSSUTIL include the following:\n\n- ACIDs\n- Jobs\n- Specific resources\n- Resource types\n• Facilities\n• Zones\n• Divisions\n• Departments\n• Dates\n• Types of access\n• CPUs\n• Violations\n• Audited incidents\n\n9.1.1.5.3 TSSCFILE\nTSSCFILE is a batch utility that produces a fixed-format output file whose records parallel the TSS LIST command output. This file is then used with a site or vendor extract tool to write customized reports based on the configuration and content of the security file. As with the other batch reporting options, scope and administrative authority limitations are honored.\n\n9.1.1.5.4 TSSREPORT and TSSREPORT2\nUnder CA Top Secret for z/OS, TSSREPORT and TSSREPORT2 use the output of TSSCFILE and TSSUTIL, respectively, to produce pre-formatted CA Earl Reports. Administrators can choose from several different report layouts, or custom layouts can be designed.\n\n9.1.1.5.5 TSSRPTST\nThe SAF Trace Report lets administrators display the monitored RACROUTE parameter list passed by requests for SAF services. This report also displays additional environmental information, such as job name, ACID, and the program issuing the SAF call.\n\nThe TSSRPTST report formats and displays the output the SAF SECTRACE command sends to SMF. To run the TSSRPTST report, an administrator must have already run the SAF SECTRACE operator command and set the output destination to SMF. With few exceptions, the TOE processes all z/OS SAF security requests by default.\n\n9.1.2 Identification and Authentication\nThe TOE controls how, when, and which resources a user can access. The TOE requires that each end user have a valid accessor ID (ACID) and password before entering the system. CA Top Secret security information is stored in a single shared database for all CPUs, the Security File. Within the Security File, each user is associated with a unique\nSecurity Record (secrec) that lets CA Top Secret associate access authorizations with users.\n\n9.1.2.1 ACIDs\nBy default, the TOE requires that all ACIDs are password protected. A Security Administrator assigns the first password. The user associated with the ACID changes the password immediately (or later) when it expires. For more information on ACIDs, see Section 9.1.3.5. Administrators can set limits as to how many violations users can accumulate per session (0-254) and define an automatic action through the VTHRESH control option. The TOE prevents further access of any kind by locking out the terminal. This forces the user to sign off. Note that the value of zero cannot be set as the threshold for lockout. Instead, once a user has been suspended, an administrator would set that value to zero to allow the individual the chance to authenticate to the TOE again.\n\n9.1.2.2 Suspended User\nThe TOE monitors the number of failed attempts to authenticate to the TOE. Once an administrator configured threshold of failed authentication attempts is surpassed for a particular ACID, the TOE will suspend that ACID. When an ACID is suspended the TOE will not allow the user/administrator associated with the suspended ACID to authenticate to the TOE. The threshold is configured by an administrator and can be set to a value within zero to 254 failed authentication attempts. Once a user/administrator has been suspended, an administrator must reactivate the suspended ACID to allow them to attempt to authenticate to the TOE again, setting the value back to zero.\n\n9.1.2.3 Authentication Methods\nThe TOE employs multiple authentication methods. The following methods are used in the evaluated configuration: Kerberos, passtickets, passwords, passphrases, and certificates. They are described in the following sections.\n\n9.1.2.3.1 Kerberos\nThe TOE employs Kerberos to store and administer authentication information for TOE users and administrators. Kerberos verifies requests as a trusted third party authentication service and confirms the identities of users and administrators.\n\n9.1.2.3.2 PassTickets\nA PassTicket is a generated character string that can be used in place of a password, with the following constraints:\n- A specific PassTicket may be used for authentication once\n- The PassTicket must be used within 10 minutes of being generated\n\nWhen a user or administrator authenticates to the TOE utilizing the PassTicket mechanism, the user/administrator must provide their PassTicket to the TOE to be checked for authorization. The TOE will then request the ICSF component to decrypt the\nPassTicket, and the TOE will then evaluate the following combinations of information to determine if the provided PassTicket can be used for authentication:\n\n1. The application name concatenated with the group name and ACID. (Note: Groups are not used in the evaluated configuration)\n\n2. The application name concatenated with the ACID.\n\n3. The application name concatenated with the group name. (Note: Groups are not used in the evaluated configuration)\n\n4. The application name.\n\nThe TOE will check each combination until one of them matches the PassTicket’s character string or all combinations have been checked. If a matching combination is found the TOE then checks the PassTicket’s session key values to determine if they are valid, and if they are this authorization check is successful and further authorization checks can be performed. Refer to Section 9.1.5 for more information on the TOE Access authorization checks. However, if none of the combinations match the PassTicket’s character string or if the session key value(s) are not valid, user/administrator has failed authentication, and the count for number of failed authentications is increased by one (refer to Section 9.1.2.7 for suspending a user/administrator).\n\nThe TOE will use the PassTicket verification process if configured by an administrator. The TOE also requires the administrator to generate a PassTicket by calling the z/OS PassTicket Generator callable service. The administrator must provide the PassTicket Generator callable service with the ACID and the APPLID which will be used for the PassTicket’s combination. The callable service will then use the current time and date stamp, and extract the necessary APPLID record from the security file to obtain the security key which the TOE will recognize as being associated with the application utilized by the user/administrator for authentication. The PassTicket Generator callable service will utilize all four pieces of information and will applying an ICSF cryptographic algorithm to the PassTicket string to generate the 8 byte PassTicket. The administrator can then provide the user/administrator with the 8 byte PassTicket.\n\n9.1.2.3.3 Digital Certificates\n\nThe TOE provides the ability to perform authorization checks based on an X.509 Digital Certificate. Digital certificates provide a means of authentication through the use of public-key cryptography and a trusted third party, known as a Certification Authority. A digital certificate is generated by the Certification Authority and is identified uniquely by its serial number and by the associated distinguished name of the Certification Authority (\"issuer's distinguished name\").\n\nA digital certificate is associated to user of the TOE through the user’s ACID record. When using certificates, the following rules apply:\n\n- More than one certificate can be added to a user’s ACID record\n- Each certificate is unique to a particular user; a certificate cannot be added to more than one ACID unless the certificate is attached to a key ring\n- In order to define multiple digital certificates, a special file (VSAM) may be needed to hold the record\n\nCA Top Secret provides complete functionality to generate, install, and maintain digital certificates, key rings, and digital certificate mappings, including the following:\n\n- Request ICSF to generate a digital certificate and a public/private key pair\n- Create a PKCS #12 certificate package\n- Create a PKCS #10 certificate request\n- Export a digital certificate or certificate package and private key from CA Top Secret to a z/OS dataset\n- Display a certificate that is in a z/OS dataset and determine if it is associated with a CA Top Secret user/administrator\n- Display a certificate registered with CA Top Secret\n- Automatically register a digital certificate with CA Top Secret\n- Associate a CA Top Secret user/administrator with a digital certificate\n- Change, display, and delete information about a digital certificate for a CA Top Secret user/administrator\n- Create, change, display, and delete a key ring\n- Add and remove a certificate from a key ring\n- Assign a CA Top Secret user/administrator to a group of certificates via User ID mapping\n- Assign a CA Top Secret user/administrator to a group of certificates based on system ID, application ID, or application-defined variables\n- Change, delete, and display a CA Top Secret User ID mapping\n\n**9.1.2.3.4 Key Rings**\n\nA key ring is a collection of digital certificates associated with an individual user. Once a user has had their identity verified to a system by a certificate that is unique to the user, the user can access additional resources through the certificates on their key ring. Key rings provide an installation-wide method to share digital certificates across multiple servers. A user can have more than one key ring.\n9.1.2.3.5 Certificate Associations\n\nCA Top Secret lets you check if a certificate has already been added to the CA Top Secret Security File and what ACID it is associated with. Once a certificate has been added to CA Top Secret it can be exported to a new data set.\n\n9.1.2.3.6 Tokens\n\nCA Top Secret employs the PKCS #11 cryptographic token standard. PKCS #11 tokens are created using the TOE’s gskkyman utility. Each token has a unique token name, or label, specified by the end user or application when the token is created. This standard is used for granting access to token information on a personal identification number (PIN).\n\n9.1.2.3.7 Password Policy\n\nPassword assignment is controlled by the TOE control option values set and stored within the TOE. The TOE requires password protection for all User and Control ACIDs by default. In addition to a password, an ACID can have an optional passphrase. Passphrases can be used instead of passwords in applications that support them.\n\nPasswords have a maximum length of eight characters. A passphrase can be from 9 to 100 characters long and can include mixed-case letters, numbers, and special characters including blanks. The same ACID can have a password for applications that accept passwords only and a password phrase for other applications.\n\nSecurity Administrators have the capability to set the TOE’s password policy. The following restrictions are available as options for Security Administrators to set the password policy for the TOE:\n\n- Minimum of one alphabetic character\n- Minimum of one numeric character\n- Prevent a user from specifying a new password that contains his 8 byte username or first four bytes of his username\n- Minimum of one lowercase letter\n- Minimum length of a password (1 to 8 characters)\n- Only numbers can be used in a new password\n- Limit the number of pairs of repeating characters in a new password\n- Initial characters match one of the entries in the Restricted Password (RPW) prefix list\n- Minimum of one character selected from the PASSCHAR list\n- Must contain a special character\n• Must not repeat characters\n• Minimum of one uppercase letter\n• Allow the administrator to create a mask to dictate the type of character accepted for each position in a password:\n o A - Any alphabetic character\n o C - Consonant\n o V - Vowel (A, E, I, O, U, and Y)\n o N - Numeric character (0 — 9)\n o X - Non-vowel (National character (@,#,$), or alphabetic including Y but excluding other vowels)\n o ? - Any character\n\n9.1.2.3.8 Password Defaults\nSecurity Administrators are able to set password defaults with the NEWPW control option. The defaults are:\n\n• The password must be at least four characters long.\n• The same letter cannot be repeated in succession.\n• The password cannot match any of the entries in the restricted password list.\n• The password cannot match the ACID or the first four characters of any word in the associated NAME field.\n• CA Top Secret issues Warning messages three days before the password expires.\n• The password cannot be too similar to the previous password.\n• Users cannot change a password more often than once each day (except for security administrators and random password users).\n\nAdditionally, a Security Administrator can generate a random password in accordance with the defined password policy. The Security Administrator would specify the ACID in the USERID field and specify the new password as “random.” Once this is done, the TOE will process the operation and generate a password at random from the requirements defined in the password policy. The new password is then provided to the user with the selected ACID who can then authenticate to the TOE.\n\n9.1.2.3.9 Passphrase Defaults\nSecurity Administrators can set passphrase defaults with the NEWPHRASE control option. The defaults are:\n• The password phrase:\n- Must be at least nine characters long\n- Can be up to 100 characters long\n\n- The TOE issues warning messages three days before the password phrase expires\n- Users cannot change a phrase more often than once each day (only Security Administrators are the exception to this rule)\n\n### 9.1.2.4 PSTKAPPL\n\nPSTKAPPL defines the application ID. Depending on the application, the secured sign on function uses a specific method to determine the application ID:\n\n- For CICS, IMS, or APPC applications, the application ID is defined using the standard naming conventions used to define these applications in a VTAM APPL statement.\n\n- For TSO, the application ID is defined by prefacing the SMF identifier of the system with the characters \"TSO\". For example, TSOXE05 is the application ID for TSO on machine MVXE05. The SMF system ID resides in the SMFPRMxx member of SYS1.PARMLIB.\n\n- For z/OS batch jobs that include CA Top Secret passwords in the JCL, replace the password with a PassTicket. The application ID for batch jobs is defined by prefacing the SMF identifier of the system with the characters \"z/OS\". For example, MVSXE05 is the application ID for all batch jobs on machine MVXE05.\n\n### 9.1.3 User Data Protection\n\nThe TOE performs access control based on Mandatory Access Control (MAC) and Discretionary Access Control (DAC) policies, which are created and modified by Security Administrators. In addition to the MAC and DAC policies, a user is granted access based on individual permissions according to his ACID, scope, and authority.\n\nWhen a user initiates a job or signs on to an online facility, CA Top Secret obtains the user's Security Record (secrec) from the Security File and places it in the user's address space for the life of the session. CA Top Secret checks all access validation against the user's Security Record.\n\nThe TOE employs the following system entry restrictions:\n• **Facility Authorization** - CA Top Secret protects access to system facilities—such as, CICS, TSO, and BATCH—by requiring that the user be authorized to use the facility. Only the MSCA can access any facility by default. All other users must be explicitly authorized to use a facility or any number of facilities through a TSS CREATE or ADDTO function. Administrators can also prevent an ACID from performing multiple simultaneous signons.\n\n• **Access Authorization** - CA Top Secret can control system entry by restricting access to terminals, readers, and CPUs. Administrators can define and restrict the following device types to CA Top Secret:\n - Online terminals (TCAM, VTAM, BTAM, VM local, logical, and bisynch)\n - Remote (RJE) and local JES readers\n - Internal readers\n - NJE nodes\n\nThe specific resource class name - such as VMRDR, TERMINAL or CPU - is the keyword to determine access authorizations and restrictions. The actual resource can be indicated by its full identifier or a Generic Prefix.\n\n• **Batch Job Validation** - A batch job must be associated with an ACID so that CA Top Secret can determine which facilities and resources it can access and how they can be accessed. To CA Top Secret, a batch job’s ACID is simply another ACID with an associated Security Record and a set of specific access authorizations. All the system entry restriction options can be specified for a User ACID, including facility, source of origin, and CPU restrictions.\n\n• **Validation** - For jobs submitted through the following entities:\n - TSO\n - CICS\n - IMS\n\nCA Top Secret provides an additional layer of security control beyond the basic batch job validation. The focus of this security layer is whether the submitter has the authority to submit the job. That is, CA Top Secret checks whether the ACID of the submitter is authorized to submit using the ACID associated with this job. If the user is not authorized, the job is flushed at submission time before the job is initiated.\n\nBy default, only defined users are allowed to submit jobs for execution under their own ACID. Explicit authority is required to allow a user to execute jobs using other ACIDs.\n\n• **Terminal Locking** - The terminal locking option protects unattended terminals against unauthorized access. Terminal locking prevents use of the terminal until it\nis logged off or unlocked. Terminal locking can be triggered automatically by CA Top Secret or through a user-initiated command.\n\n- **Automatic Locking** - CA Top Secret automatically locks a terminal that has been inactive for a pre-established duration. Automatic locking thresholds can be established at both the user and facility level.\n\n- **Console Protection for MVS** - CA Top Secret provides several protection options designed to prevent operators or other personnel from executing sensitive started tasks or changing security control options without proper identification and password authentication.\n\n### 9.1.3.1 Resource Classes\n\nThe objects that CA Top Secret protects are called resources. Resources must be owned before their use can be authorized (see Section 9.1.3.1.1 for further information on resource ownership). Each resource in CA Top Secret is an instance of a Resource Class (RESCLASS). The types of resources (such as data sets, volumes, terminals, and minidisks) that CA Top Secret protects appear in the Resource Descriptor Table (RDT). The resource types are automatically defined to the RDT at installation. Some resource classes can be used in multiple facilities. Other resource classes are specifically defined for individual environments. Resources are used throughout the system to protect the objects and services provided by jobs, tasks, and sessions in multi-user environments.\n\nMost resource classes are defined as GENERIC, which allows all resources with the same prefix to be protected by the same command. A NONGENERIC definition requires complete specification of each resource by individual commands. Resource classes defined as DEFPROT automatically protect all resources in the class, regardless of whether an explicit command has been issued to establish ownership. If the TOE is not aware of a resource and its existence, it will not protect it. The following table lists the default resource classes.\n\n<table>\n<thead>\n<tr>\n<th>Interface</th>\n<th>Resource Classes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Base CA Top Secret products</td>\n<td>DATASET</td>\n</tr>\n<tr>\n<td></td>\n<td>PROGRAM</td>\n</tr>\n<tr>\n<td></td>\n<td>OPERCMDS</td>\n</tr>\n<tr>\n<td></td>\n<td>SECLABEL</td>\n</tr>\n<tr>\n<td></td>\n<td>TSOAUTH</td>\n</tr>\n<tr>\n<td></td>\n<td>UNIXPRIV</td>\n</tr>\n<tr>\n<td></td>\n<td>FACILITY</td>\n</tr>\n<tr>\n<td></td>\n<td>IBMFAC</td>\n</tr>\n<tr>\n<td>CA Top Secret CICS Interface</td>\n<td>OTRAN</td>\n</tr>\n<tr>\n<td></td>\n<td>TCICSTRN</td>\n</tr>\n<tr>\n<td></td>\n<td>FCT</td>\n</tr>\n<tr>\n<td></td>\n<td>PPT</td>\n</tr>\n<tr>\n<td>CA Top Secret IMS Interface</td>\n<td>CIMS</td>\n</tr>\n<tr>\n<td></td>\n<td>TIMS</td>\n</tr>\n<tr>\n<td></td>\n<td>IIMS</td>\n</tr>\n</tbody>\n</table>\n\n**Table 9-1: Resource Classes Included in the Evaluated Configuration**\nNote: OTRAN and TIMS are used for transactions. CIMS is used for commands. IIMS is used for PSBs.\n\nPermission can be restricted under the control of the RDT definition:\n\n- **ACTION** - Indicates unusual actions or modes associated with the permission.\n- **ACCESS** - Restricts the access levels that are permitted.\n- **LIB** - Restricts the program from which the permission is initially executed to a specific data set.\n- **PRIVPGM** - Restricts the program from which the permission is initially executed to a specific program.\n\nEach resource in the class has security protection even if it is not defined to the TOE. A security violation occurs when a request is made to access the resource.\n\nA User’s or an administrator’s access to resources can be restricted by day, time, facility, program, or access level. Resource protection can also be extended on a default or global basis. Most resources, however, do not require full default protection. Resources to the RDT can be defined dynamically in order to assign default protection.\n\nSecuring resources is a two-step process. Once the resource type or class is defined in the RDT, then each resource must be:\n\n- Assigned ownership by an individual or department ACID\n- Permitted access to additional ACIDs (if necessary)\n\n### 9.1.3.1.1 Resource Ownership\n\nAs aforementioned, resources must first be owned before usage of that resource can be authorized. Ownership of a resource automatically implies full access to that resource. Zone, division, department, profile, and user ACIDs can own resources. For other ACIDs to have access to that resource, they must first be authorized or permitted to do so. Furthermore, only users and profiles can be granted access to resources.\n\nAfter the resource class is defined to the RDT, the ACIDs that have ownership of the individual resources within that class must be determined. Assigning ownership allows for the individualization of access restrictions for particular resources within the resource class. Resource ownership implies that the owning ACID has an access level of ALL. As it may not be desirable to grant unlimited access to individual users or profiles, resource ownership should be relegated to a Department or Division ACID using the ADDTO command function. At that point, full or restricted resource access can be authorized for other, non-owning ACIDs using the PERMIT command function.\n9.1.3.2 Security Validation Algorithm\n\nOnce all resources have been defined to CA Top Secret and their access levels have been specified, any future request to access those resources is processed through the TOE’s validation algorithm. The Security Validation Algorithm determines whether an ACID has the appropriate authorizations and permissions to access a particular resource.\n\nThe security validation algorithm considers factors such as the security mode, resource ownership, the order of permissions, and the use of the installation exit in order to determine which resources (if any) the user is allowed to access. The algorithm determines whether the requested access is granted by searching these records in the following order:\n\n1. The user record\n2. Each attached profile in the order they were attached\n3. The ALL Record, if included in the search sequence\n\nWhether the algorithm grants access depends on:\n\n- The value selected for the AUTH control option. This value controls how the records are searched, which records are included in the search, and when to stop the search.\n- Whether a user has specified the ATTR keyword for RESCLASS.\n- Whether the request is for a volume, a data set, or another resource.\n\nIf the algorithm locates multiple PERMITs for the resource, the algorithm selects the PERMIT that most closely matches the request.\n\nThe security validation algorithm consists of:\n\n- The AUTH control option to determine how the algorithm works.\n- (Optional) The ATTR keyword of a resource class to fine-tune the search by specifying how the search is performed for specific resources.\n\n9.1.3.2.1 Volume Request Processing\n\nWhen validating access to a volume, the Volume Call is invoked first. This call grants or denies access to the volume or data set or allows normal processing to continue. Volume access overrides data set access as shown in the following chart. Before processing continues, CA Top Secret inquires about the records being searched, asking the following questions:\n• Does the ACID have the NOVOLCHK attribute?\n• Does the ACID own the volume?\n• Was an access PERMIT found?\n• Were multiple PERMITs found for the requested resource?\n\nA PERMIT is not checked if it has an access level of:\n• BLP when the access request is for a DASD volume of a data set\n• CREATE, SCRATCH, or CONTROL if the access request is for a tape volume\n\n9.1.3.2.2 Criteria for Volumes\nThe criteria to determine best fit for volumes are:\n• A valid PERMIT with full access to the volume is considered a match.\n• A volume PERMIT with an access level of CREATE is considered a match when the request was for data set CREATE (data set checking follows).\n• The first violation due to access level mismatch denies access.\n• The first violation for any other reason (for example, DAY, TIME, FACILITY, or PRIVPGM mismatches) denies access.\n\n9.1.3.2.3 Data Set Requests\nCA Top Secret performs tape data set checking when a DSNAME has been opened for TAPEVOL calls when the TAPE (DSNAME) control option is in effect. When an ACID requests access to a particular DASD data set, the pertinent volume and data set access authorizations must be evaluated depending on what bypass options are associated with that ACID or PERMIT. The bypass options include whether the ACID has NODSN access for that specific request, and whether that ACID has been given the NODSNCHK or NOVOLCHK attributes.\n\nWhen CA Top Secret is checking both volume and data set level access, CA Top Secret always performs volume level first. In some cases, a request to access a data set is granted or failed strictly based on the ACID's volume access authorizations, without checking whether the user has specific authorization to access that particular data set.\n\nThe following table shows how volume access authorizations affect an ACID's request to access a data set on a volume:\nThe table can only be used for requests where both volume and data set authorizations are checked. For cataloging a tape data set, a CREATE access check occurs only at the data set level. This is independent of the setting of the TAPE control option. No volume check is made, so even having ALL access at the volume level will not allow a tape data set to be catalogued. In addition, when allocating an SMS-managed data set, no volume is identified on the data set call and no volume checking occurs.\n\nIf a VOLUME check that was qualified by PRIVPGM, FACILITY, DATE, or TIME denies access on a data set request, this rule of data set authorization relationships are honored, rather than continuing to the DATASET name checking.\n\nNote the following:\n\n- If the user has both CREATE and CONTROL access, data set creation is performed regardless of the data set name.\n- A VSAM control (delete and define) would require data set scratch and data set create.\n\n### 9.1.3.2.4 Criteria for Data Sets\n\nThe criteria to determine best fit for data sets are:\n- PERMITs using quotes (for example, 'A.B.C. ') are considered matches.\n- PERMITs without quotes but not starting with a masking character are considered matches.\n- PERMITs starting with a mask are considered matches.\n- A valid PERMIT with an access level of ALL is considered a match.\n- The first violation against a FETCH-protected data set denies access.\n- The first access level mismatch denies access.\n- The first violation for any other reason (for example, DAY, TIME, FACILITY, or PRIVPGM mismatches) denies access.\n\n9.1.3.2.5 General Resource Requests\n\nWhen a user requests access to a particular resource, the security validation algorithm determines CA Top Secret access authorizations. When multiple PERMITs are found, the algorithm determines access by best fit, rather than by the most restrictive match. The TOE makes the following inquiries about the records being searched:\n\n1. **Does the ACID have NORESCHK?**\n - Yes: Processing stops and access is granted.\n - No: Individual authorizations are checked based on AUTH option setting.\n\n2. **Does the ACID own the resource?**\n - Yes: Processing stops and full access is granted.\n - No: PERMITs are checked, except for expired PERMITs.\n\n3. **Access PERMIT Found?**\n - Yes: CA Top Secret checks for additional PERMITs to that resource.\n - No: Access denied.\n\n4. **Multiple PERMITs for that resource?**\n - Yes: CA Top Secret selects best fit.\n - No: Access is granted according to PERMIT conditions.\nWhen the algorithm locates multiple PERMITs during its search, the algorithm selects the PERMIT that most closely matches the request according to a set of criteria.\n\nThe following criteria are always the same for all resource types (volumes, data sets, and general resources):\n\n- The first criterion is the longest resource name specified. When the algorithm locates multiple PERMITs, the one containing the longest resource name is considered the best match, unless the PERMIT begins with a masking character.\n- If the PERMIT is valid but the access level for the resource is NONE, CA Top Secret denies access.\n\nTo determine the longest resource name, each character in the resource name counts as one character whether it is a normal character or a masking character. If the floating mask “-“ is used in a PERMIT, only the characters prior to the mask are counted. If the best fit cannot be determined by resource name length or an access level of NONE, then the criteria to determine the best fit differs for volumes, data sets, and general resources.\n\n### 9.1.3.2.6 General Resources Criteria\n\nThe criteria to determine best fit for other resources are:\n\n- The first violation due to access level mismatch denies access.\n- The first violation for any other reason (for example, DAY, TIME, FACILITY, or PRIVPGM mismatches) denies access.\n\n### 9.1.3.3 Discretionary Access Control\n\nThe TOE enforces the Discretionary Access Control (DAC) policy to objects based on users, entity, security relevant attributes control option auth, resource class name, entity name, secrec, ownership, facility, time of day, day of week, sysid, Limited Command Facility (LCF), calendar, program, and library.\n\nNote: users can be applications issuing a RACROUTE call. An entity can be a data set, program, or an issued command.\n\n### 9.1.3.3.1 Secrecs\n\nA secrec is a list of permission entries that contain a resource class, a resource entity, and the highest-level operation allowed by that user. The entity name can be a partial match (e.g. sys.*). The “control options auth” attribute will determine when to stop searching the various secrecs of the user. The Security user has many secrecs:\n• **User** – A user secrec is unique to the user. Each user has one user secrec.\n\n• **Profile** – A user has a secrec for each profile assigned to that user. Each user can have one or several profile secrecs.\n\n• **All** – The all secrec is the permissions shared by all users. Each user has one all secrec.\n\nThe secrecs are searched according to the chosen mode in order to determine a user’s access. The access modes included in the evaluated configuration are:\n\n• **Override allover** – A value of “override allover” for the control options auth attribute will look through each secrec one record at a time until it finds an entry that matches the entity and will compare the permission in that entry to the request permission to determine if access is allowed. Once a matching entity record is found, the search will stop at the end of that secrec and return the best fit (longest length entity name that matches). If there is more than one entry of the same length, it will return the most permissive operation value unless it is defined as “None” or “ActionDenied.\"\n\n• **Merge allover** – A value of “merge allover” will search every secrec for the best fit and only process the all record (i.e. all secrec) if the search yielded no results.\n\n• **Merge allmerge** – A value of “merge allmerge” will search every secrec including the all record and return the best fit among all secrecs searched.\n\nTable 9-1 shows the stopping point for checking each secrec.\n\n<table>\n<thead>\n<tr>\n<th>Access Mode</th>\n<th>Secrec</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Override allover</td>\n<td></td>\n</tr>\n<tr>\n<td>Merge allover</td>\n<td>User</td>\n</tr>\n<tr>\n<td>Merge allmerge</td>\n<td>Profile 1</td>\n</tr>\n<tr>\n<td></td>\n<td>Profile n</td>\n</tr>\n<tr>\n<td></td>\n<td>All</td>\n</tr>\n</tbody>\n</table>\n\n**Table 9-2: Access Modes**\n\nThe TOE will permit the requested operation to the protected object (i.e. entity), if the user has a matching secrec entry that matches the class, partial entity name, facility, time of day, day of week, calendar (i.e. day of the year), sysid, program (and library) in the program path, and has an operation in that entry that dominates the requested operation. Furthermore, each secrec that uses LCF will have an inclusion or exclusion list for the command issued. If that command is in the excluded list defined by LCF, the command will fail to execute. If the command was not on an inclusion list, the command will fail.\nto execute. If the value of facility, time of day, day of week, calendar, sysid, library, program or LCF is not present, then no comparison is done for those attributes.\n\n### 9.1.3.3.2 LDAP Directory Services\n\nAn LDAP directory provides a method to maintain directory information, such as email accounts, in a central location, for storage, update, retrieval, and exchange. LDAP directories can be utilized as network accessible databases for organization and indexing of network security information.\n\nLDS uses the LDAP protocol and native TCP/IP to communicate the changes from the CA Top Secret Security Databases to the remote LDAP repository. Servers enabled with Secure Sockets Layer (SSL) technology protect unauthorized parties from viewing sensitive information during a secure session. Using the XREF mapping record, you configure which LID fields are to be sent to the remote repository and what the remote attribute name is.\n\nWhen CA Top Secret uses LDS to connect to the remote LDAP directory, it is the client application to the remote LDAP Server. Using the standard LDAP protocol, CA Top Secret formats the add, modify, or delete request and sends it to the remote LDAP Server.\n\n### 9.1.3.4 Mandatory Access Control\n\nThe TOE enforces the Mandatory Access Control (MAC) policy to objects based on users, resources, Access Level, Type, Object Security Label, and Subject Security label.\n\n*Note: Users can be applications issuing a RACROUTE call. Resources can be data sets, programs, or an issued command.*\n\nThe type of access granted to a user is based on the values of TYPE and ACCESSLevel, as defined below:\n\n<table>\n<thead>\n<tr>\n<th>ACCESSLevel</th>\n<th>Type=MAC</th>\n<th>Type=EQUALMAC</th>\n<th>Type=RVRSMAC</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Read</td>\n<td>User Dominates</td>\n<td>Equivalence</td>\n<td>Resource Dominates</td>\n</tr>\n<tr>\n<td>Read/Write</td>\n<td>Equivalence</td>\n<td>Equivalence</td>\n<td>Equivalence</td>\n</tr>\n<tr>\n<td>Write</td>\n<td>Resource Dominates</td>\n<td>Equivalence</td>\n<td>User Dominates</td>\n</tr>\n</tbody>\n</table>\n\n*Table 9-3: Mandatory Access Control*\n\nFor example, if the TYPE = MAC, the following rules apply:\n\n- Read access will be allowed if the security label on the subject dominates the object.\n- Read/write access will be allowed if the security label on the subject and object match.\n- Write access will be allowed if the security label on the object dominates the user.\n\n*Note: For all access decisions, the TOE first checks the MAC policy, followed by the DAC policy.*\nThe enforcement of MAC prevents the system from allowing data with higher sensitivity security labels from being disclosed to a user with a lower security label. For instance, a user with a high label cannot send a highly sensitive data set to a user with a lower security label. This is known as “simple security property” and “confinement property.” This is also covered within “write-down” protection that is provided by the TOE.\n\n9.1.3.4.1 MAC Label Dominance\n\nIn an MLS system, most users use a security label only when they log on to the system or submit a job. The rest of the time, security labels are read, decoded, and applied by the TOE and the system. Security administrators can create and assign security labels based on their organization's security policy. In addition, depending on what MLS system options have been set, the TOE will assign a security label to data when it is created.\n\nWhen users log on to a system, they can enter a security label. The TOE verifies that they are authorized to use the label by checking their user ACID record. If a user is authorized to use the security label, the TOE maintains the security label in the user’s address space and uses it to make access decisions until the user logs off.\n\nUsers cannot alter their security label while logged onto the system.\n\nWhen MLS is active in the TOE, MAC security label checking is performed before DAC access rule checking, except in the case of system entry where a user must be identified to the system before label validation can be performed.\n\n- If MAC allows an access, a request must still pass through DAC validations to ultimately allow or deny access.\n- If MAC denies access, the request is denied and does not go through DAC validations.\n\nThe TOE determines MAC access based on the dominance relationship between the label of the object and the label of the subject that is trying to access the object. The factors that the TOE uses to determine the dominance relationship are:\n\n- Simple security property\n- Confinement property (*-Property)\n\nFor example, if there are two security labels, X and Y:\n\n- X dominates Y if:\n - The level of X is greater than or equal to the level of Y, and\n - X contains at least all categories contained in Y\n- X is disjoint from Y if neither X nor Y includes all the categories of the other\nIn the first rule (X dominates Y), above, both conditions must be true for Label X to dominate Label Y. So, the “and” is important. If the Level of X is less than the Level of Y, then the dominance check has already failed and Label X will never dominate Label Y. However, if the Level of X is greater than or equal to the level of Label Y, then, the categories of Label X and Label Y must be compared to see if all the categories in Label Y are in Label X. If Label X's level is higher than Label Y’s, dominance has not yet been established, until the categories are compared. In the second rule (X is disjoint from Y), above, if neither security label X nor Y includes all the categories of the other, the labels are said to be incomparable or disjoint; neither one dominates.\n\nNote: The term “greater than” is used informally to mean dominates. Although labels cannot be compared in a numerical sense, the concept of “greater than” is a convenient way to think of label dominance.\n\n9.1.3.4.2 Types of MAC Label Dominance Checks\nThere are three types of MAC label dominance checks in the MLS system:\n\n- MAC dominance check\n- Reverse MAC dominance check\n- Equal MAC dominance check\n\nThe type of label dominance check performed for each requested access to a classified resource depends on what the resource’s class is and whether write-down is restricted (preventing declassification of data in writing from a higher classification to a lower classification).\n\n9.1.3.4.3 MAC Dominance Check\nThe MAC dominance check requires that because opening a data set for write access implicitly opens it for read access, to read-only or read/write to a data set, the user's label must dominate the data set's label. However, there are other resources that support true write-only access such as messages sent with the TSO SEND command and batch jobs submitted through the internal reader. To write-only when write-down is not restricted in an MLS system, the user's label and the resource's label must be comparable, for example, not disjoint. In other words, the user's label must dominate the resource's label or the resource's label must dominate the user's label.\n\n9.1.3.4.4 Reverse MAC Dominance Check\nThe reverse MAC dominance check is the opposite of the MAC dominance check. Reverse MAC dominance requires that the resource's security label dominates the user's security label for the requested access to be allowed.\n9.1.3.4.5 Equal MAC Dominance Check\nIf two labels are equal, they dominate each other. Equal MAC dominance checking, which is used for any class that requires two-way communication, requires that the user and resource security labels are the same for the requested access to be allowed.\n\n9.1.3.5 ACIDs\nBy default, the TOE requires that all ACIDs are password protected. A Security Administrator assigns the first password. The user associated with the ACID changes the password immediately (or later) when it expires. An ACID represents many different structures within the TOE, from a USER or a PROFILE to a structure like a Department.\n\nCA Top Secret validates ACIDs in different ways to protect against unauthorized use. First, CA Top Secret checks the security file to determine whether a designated ACID is defined. It does this by seeing if a security record exists for it. Second, if the ACID is undefined, CA Top Secret responds based on the initial control option settings for the security mode and various system options.\n\nAn ACID's authorization to access a resource is determined by the PERMITs in:\n- The user's record\n- The profile records attached to the user's ACID\n- The ALL record, which lists globally accessible resources\n\nAn ACIDs access can be restricted to:\n- A particular terminal or CPU\n- Access only on particular days of the week or during certain hours\n- Access through a particular facility, such as TSO or CICS\n\nAn ACID can be up to eight alphanumeric characters long, which normally corresponds with the user’s system userid. The same ACID can be used for all facilities or a different ACID can be used for each facility (such as TSO, CICS, and z/VM).\n\nCA Top Secret recognizes several different types of ACIDs, ranging from a user to an entire zone. These types comprise the basic hierarchical structure of the CA Top Secret database. Each ACID type is then associated with a set of resource access authorizations.\n\n9.1.3.5.1 Functional ACIDs\nFunctional ACIDs are associated with organizational units that are defined by organizational ACIDs. This association determines the authorizations that these\nfunctional ACIDs have to interact with objects protected by the TSF which reside in the Operational Environment. The functional ACIDs available are:\n\n- **User ACIDs** - The user is a person. Individuals are associated with user ACIDs or control ACIDs. A user ACID designates a specific employee in a department but can refer to any ACID type (functional or organizational). Every user ACID must be associated with a single department ACID.\n\n- **Profile ACIDs** - When a group of users needs to use a set of identical resources in the same way (the users perform similar or related job functions), define this set of access authorizations once and then associate the entire set with each of the users in the group. In CA Top Secret, this set of common resource access characteristics is termed a profile. Every profile is assigned a unique profile ACID. Once a profile is defined, it can be associated with any number of users (at the same or different levels in the hierarchy), thereby eliminating the need to define each resource access authorization separately for every user. Every profile ACID must be associated with, and defined to, a single department ACID.\n\n9.1.3.5.2 **Organizational ACIDs**\n\nOrganizational ACIDs report to other organizational ACIDs. Organizational ACIDs never report to functional ACIDs. The organizational ACIDs available are:\n\n- **Department ACIDs** - Users typically work for a particular department. CA Top Secret recognizes this logical separation by requiring each user ACID to be associated with one department ACID. Every department is assigned a unique Department ACID. In the evaluated configuration, resources are assigned to a department.\n\n Note: A Department ACID cannot be directly attached to a Zone ACID. This ACID must be attached to a Division ACID that is attached to a Zone ACID.\n\n- **Division ACIDs** – Multiple divisions can be defined within the security structure. Each division is composed of one or more departments. Every division is assigned a unique division ACID.\n\n Note: A division can have one or more VCA administrative ACIDs assigned to administer various authorities for other ACIDs assigned to the division.\n\n- **Zone ACIDs** - A zone is used to group two or more divisions. Every zone is assigned a unique zone ACID. Resources can be assigned to a zone. A Department ACID cannot be directly attached to a Zone, but it can be attached to a Division ACID, which is attached to a Zone ACID.\n\n Note: A zone can have one or more ZCA administrative ACIDs assigned to administer various authorities for other ACIDs assigned to the zone.\n\n- **Control ACIDs** – A Control ACID is an ACID that can be logged on to the system as an administrator. This defines security administrators that are\nassociated with various structural levels within the CA Top Secret security file. A control ACID can be a regular user of system facilities. A control ACID can issue subsystem commands and perform other functions—such as access data sets and submit jobs. Initially, CA Top Secret knows of only one control ACID—the MSCA ACID—for the security administrator. This ACID is defined during installation. Each type of control ACID performs administrative tasks for the structural level it is associated with. To enable the control ACID to perform these tasks, each one is assigned a scope of authority and administrative authorities within that scope. The TOE, by design, is a hierarchy. Each ACID within a department, division, or zone has its own type of control ACID (MSCA, DCA, VCA ZCA and special types like LSCA and SCA). The C in each of those names means Control.\n\n9.1.3.5.3 Model ACIDs\n\nModel (also referred to as template) ACIDs are used when creating a large number of new ACIDs. Basic information is copied from the model ACID, where the security administrator has the ability to change, add, or omit any basic information from the model. Basic information can include, but is not limited to, the name associated with the ACID, password, ACID type, facilities permitted access, and associated profiles. An existing ACID can be used as the model or template. In addition, all ACID types can be created.\n\nModel ACIDs support all rules of scope and administrative authority. If the model ACID is outside the scope of the security administrator and/or the model ACID has an information field that requires ADMIN authority the security administrator does not have, the model ACID cannot be used to create the new ACID.\n\n9.1.3.5.4 Pre-Defined ACIDs\n\nCA Top Secret has reserved or special ACIDs and tables that are pre-defined and maintain resource and attribute information. These include:\n\n- **ALL Record** - Identifies resources that are globally accessible to all signed on users.\n\n- **APPCLU Record** - Stores the names and security requirements of the logical units (LUs) involved in APPC conversations.\n\n- **Audit Record** - Stores the resource names that are to be audited.\n\n- **Data Lookaside Table (DLF)** - Controls the loading of selected data sets into ESA hyperspace by selected jobs. With the proper authority and keywords, CA Top Secret can identify and control those data sets and jobs valid for DLF.\n\n- **Delegate Record** - Contains delegate resource definitions. Each definition specifies a resource class and entity name used in nested ACEE processing.\nThe Security Administrator is responsible for the scope of authority. The TOE provides several different levels of control ACID scope. Each level corresponds to a level in the corporate structure. For example, a division control ACID (VCA) is responsible for administering security for all the ACIDs within a particular division (including ACIDs assigned to departments associated with that division). The following table shows an example of how security administrators can be defined, and the scope that result:\n\n<table>\n<thead>\n<tr>\n<th>Title</th>\n<th>Scope</th>\n<th>Example</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>MSCA</td>\n<td>Entire installation</td>\n<td>The master SCA (MSCA) can create all CA Top Secret administrators, including SCAs, LSCAs, ZCAs, DCAs, VCAs, and auditors.</td>\n</tr>\n<tr>\n<td>SCA</td>\n<td>Entire installation</td>\n<td>An SCA’s scope of authority depends on the administrative authorities that they were granted. An SCA can create ZCAs, DCAs, VCAs, Profile, and User ACIDs, but not other SCAs.</td>\n</tr>\n<tr>\n<td>LSCA</td>\n<td>A zone and/or another LSCA</td>\n<td>An LSCA can have all the authority of an SCA, but unlike the SCA, the LSCA must have a scope of authority assigned to it. This scope of authority can be</td>\n</tr>\n</tbody>\n</table>\n| ZCA | A zone | Permit access to resources owned by his zone, all connected divisions, departments and users within that zone. \nDefine profiles and perform maintenance for ACIDs that are within his scope. \nCreate ACIDs in his zone. \nPermit ACIDs in other zones to access his zone's resources, but cannot perform maintenance for ACIDs in other zones. |\n| VCA | A division | Permit access to resources owned by his division, all departments and users within that division, and can define profiles and perform maintenance for ACIDs that are within his scope. \nCreate ACIDs in his division. \nPermit ACIDs in other divisions to access his division's resources, but cannot perform maintenance for ACIDs in other divisions. |\n| DCA | A department | Department administrators have the same scope over a department that a VCA has over a division. DCAs can also create ACIDs in their department. |\n\nTable 9-4: Security Administrators and Associated Scope of Authority\n\nFor more information on the types of Security Administrators, see Section 9.1.4.1.\n\n9.1.3.7 Authority\nIn addition to scope of authority, each Security Administrator must also be assigned particular types of administrative authorities. These authorities define the security functions the control ACIDs can perform for ACIDs within their scope. Upper level security administrators can grant administrative authorities to lower level administrators within their scope, provided the higher-level administrators already possess the appropriate authorities.\n\n9.1.3.7.1 Types of Administrator Authorities\nAn ACID's authority determines what can be done with the administration of ACIDs, resources, facilities, and the display of security file information. The administrative authorities are:\n\n- ACID\n- DATA\nEach type of authority approximately corresponds to a different set of security environment control and maintenance functions (for example, ACID maintenance or resource maintenance).\n\nA group of operands is associated with each type of authority. Each operand designates a specific functional authority. For example, ACID(CREATE) authority lets the control ACID create and delete ACIDs within their scope, while RESOURCE(INFO) lets the control ACID perform certain inquiries for any resource within their scope.\n\nNote: Administrative authorities cannot be assigned to a zone, division, department, group or profile ACID.\n\n9.1.3.7.2 Global Authorities\nTo give every ACID the ability to perform specified administrative functions, the administrator can assign the administrative authority to the ALL record. For example, assigning MISC1(LTIME) to the ALL record gives all ACIDs the authority to set their own terminal lock time interval. The ALL record can also contain resources access levels.\n\nOnly administrators with MISC9(GLOBAL) authority can assign administrative authorities to the ALL Record.\n\n9.1.3.8 Facilities\nA facility is a way of grouping options associated with a particular service that users sign on to. To sign on to a service, a user must have access to the facility. Only the MSCA can access any facility by default. All other TOE users must be authorized to access one or more facilities.\nIn the evaluated configuration, the TOE provides security for the following facilities:\n\n- **CICS** – Associated with the appropriate facility in the following ways:\n \n - Explicitly - By assigning a MASTFAC parameter to the ACID executing the batch job or STC that created the service.\n \n - Implicitly - CA Top Secret looks at the program in control and matches it with the program name specified in the facility. If there is not a match for the INITPGM or no MASTFAC was assigned, a facility of STC is assigned if the particular service was started as a started task. If the service was started as a batch job, the facility of BATCH is assigned.\n \n - Multiple user address space - each user that signs on to a CICS region is given part of the region's block of space. When a user requests access, standard CICS only identifies to z/OS the Security Record for the region involved, not the specific user's Security Record. This procedure is typical of multiple user address space systems.\n\n- **IMS** – Associated with the appropriate facility in the following ways:\n \n - Explicitly - By assigning a MASTFAC parameter to the ACID executing the batch job or STC that created the service.\n \n - Implicitly - CA Top Secret looks at the program in control and matches it with the program name specified in the facility. If there is not a match for the INITPGM or no MASTFAC was assigned, a facility of STC is assigned if the particular service was started as a started task. If the service was started as a batch job, the facility of BATCH is assigned.\n \n - Multiple user address space\n\n- **TSO** - Single user address space. Each signed on user gets his own address space.\n\nNote that storage keys protect the security data area in the user address space. User programs are normally allowed to only modify storage key 8 while security data is kept under either key 0 or key 3. These two storage keys require programs to be in that key to modify them. These programs must be APF authorized and running in a supervisor state. User programs are not allowed to receive this authorization.\n\nConsiderations for implementing CA Top Secret for CICS and IMS are similar because the security interfaces behave in a similar fashion. The transactions and resources available within CICS and IMS are similar in that the resources available in TSO, but have different names. This table shows the relationship among the resources appropriate to each facility.\n\n<table>\n<thead>\n<tr>\n<th>TSO</th>\n<th>CICS</th>\n<th>IMS</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Commands</td>\n<td>Transactions</td>\n<td>Transactions</td>\n</tr>\n<tr>\n<td>Programs</td>\n<td>PPTs</td>\n<td>PSBs</td>\n</tr>\n</tbody>\n</table>\n9.1.3.9 Access Restrictions\n\n9.1.3.9.1 Time of Use Monitoring\nAdministrators can control when an ACID can enter the system through a facility or device by specifying the following time-related parameters:\n\n- **DAYS** - Specifies the day of the week.\n- **TIMES** - Specifies the time of day.\n- **FOR/UNTIL** - Specifies a particular length of time.\n- **CALENDAR** - Specifies an inclusive or exclusive list of dates, which gives users the ability to establish calendars to reflect site-specific events (such as company holidays). The CALENDAR specified does not need to exist to do the permission; however, the PERMIT does not execute correctly until the named record exists in the Static Data Table (SDT).\n- **TIMEREC** - Specifies multiple time intervals within a 24-hour day. Administrators can specify multiple 15-minute intervals within a 24-hour day when access to a resource is permitted. The TIMEREC specified does not need to exist to do the permission; however, the PERMIT does not execute correctly until the named record exists in the SDT.\n\nNote: The DAYS and CALENDAR keywords are mutually exclusive. Any existing permissions that use the DAYS keyword can be replaced with a permission that uses the CALENDAR keyword. Similarly, the TIMES and TIMEREC keywords are mutually exclusive. Permissions that use the TIMES keyword can be replaced with a permission that uses the TIMEREC keyword.\n\n9.1.3.9.2 Restrictions by Device\nCA Top Secret can control system entry by restricting access to:\n\n- CPUs\n- Online terminals (TCAM, VTAM, BTAM, VM local, logical, and bi-synch)\n- Remote (RJE) and local JES readers\n- Internal readers\n- NJE nodes\n\nThe specific resource class name (CPU, TERMINAL, VMRDR, and NODES) is used as the keyword to determine access authorizations and restrictions for that resource.\n9.1.3.9.3 Multiple Node Users\n\nOnly users defined to the target node can initiate jobs on that node. To define users to multiple nodes, administrators must adhere to the following requirements:\n\n- If CA Top Secret is running on all nodes and each node has its own security file, the Command Propagation Facility (CPF) is used to propagate security information for a user across all nodes while only entering it once.\n\n- If CA Top Secret is running on all nodes that share the same security file, then each user is implicitly defined to every other node in the system.\n\n9.1.3.10 Security Modes\n\nCA Top Secret for z/OS r14 uses several security modes to assist in access control. However, only Fail mode is included in the evaluated configuration. During Fail mode, the TOE is in full control of access requests. All users must be defined and resources protected by being owned or by DEFPROT protection. All unauthorized access requests fail by default. For more information on the excluded security modes, see Section 2.3.\n\n9.1.3.11 Object Reuse Protection\n\nA z/OS system ensures that no user or program can scavenge data from an object after it has been deleted. Object reuse protection ensures that when a user deletes an object such as a data set, that object is physically erased. Without object reuse protection, the storage would be returned to the storage pool without erasure. A user who obtained storage for a new data set could read the storage and find out what the previous user had put in the data set.\n\nObject reuse protection applies not only to data set objects but also to all objects defined in the system, including address spaces, messages, and devices. A CA Top Secret system provides object reuse protection for data sets if the AUTOERASE control option is specified. Object reuse protection for other objects is provided automatically.\n\nThe AUTOERASE and AUTOEDSN control options govern whether automatic erase is active in a CA Top Secret environment and, if so – the specific data set names/data set name prefixes that are eligible for automatic erase processing. In the evaluated configuration, both these control options are enabled.\n\nCA Top Secret itself does not perform the actual physical data erasure. When a user makes a request to delete a data set, it results in a request to the access method in the Operational Environment to perform the data set delete. Deletion of a data set entails removal of the data set entry in the volume table of contents (VTOC) on one or more volumes (if multi-volume) and optionally the related catalog. The actual data contents themselves remain largely intact.\n\nWhen a user issues a delete for a data set, the platform will issue an access method service to perform the actual delete. The access method routines will then issue a SAF security call to ascertain the user’s authority to delete the data set. If the user is permitted\nto perform the delete, the access method will go about the task of data set deletion. If the user is denied, the data set will not be deleted.\n\nThe access method passes an indicator, STATUS=ERASE, on the RACROUTE REQUEST=AUTH request which interrogates the external security manager (ESM) for erase characteristics of that to-be-deleted data set. The ESM responds to the access method through a reason code when the access is allowed.\n\nA returned reason code value of zero means that the data set should not be erased; a reason code value of four means that the data set should be erased. The TOE will set reason code zero or four based on the access determination and the settings of the AUTOERASE and AUTOEDSN control options in relation to the data set object being deleted. The access method itself is responsible for performing the actual data erasure when reason code=four is returned.\n\n### 9.1.4 Security Management\n\nThe TOE maintains three roles – security administrators, scoped security administrators, and users. Administrators manage the TOE and its users; whereas a user’s primary function is to perform work. Any administrator with ACID(CREATE) administrative authority can establish users. The table below describes what functions a user can perform.\n\n<table>\n<thead>\n<tr>\n<th>AccessLevel (DAC)</th>\n<th>DIRAUTHLevel (MAC)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Read</td>\n<td>Read</td>\n</tr>\n<tr>\n<td>Create</td>\n<td>Read</td>\n</tr>\n<tr>\n<td>Write</td>\n<td>Write</td>\n</tr>\n<tr>\n<td>Control</td>\n<td>ReadWrite</td>\n</tr>\n<tr>\n<td>Update</td>\n<td>ReadWrite</td>\n</tr>\n<tr>\n<td>Scratch</td>\n<td>ReadWrite</td>\n</tr>\n<tr>\n<td>Fetch</td>\n<td>ReadWrite</td>\n</tr>\n<tr>\n<td>Alter</td>\n<td>ReadWrite</td>\n</tr>\n</tbody>\n</table>\n\n**Table 9-6: User Performed Operations on the TOE**\n\nAdministrators can perform the following functions:\n\n- Define default subject security attributes (nothing is set by default, therefore default is NONE)\n- Change subject security attributes\n- Manage user identities\n- Manage the authentication data by an administrator\n- Control the authentication data that users are allowed to manage\n- Manage the authentication data (i.e., passwords) by the associated user\n- Manage the metric used to verify and generate the secrets\n• Define additional security attributes for users\n• Manage the threshold for unsuccessful authentication attempts\n• Manage the actions to be taken in the event of an authentication failure\n• Manage the attributes used to make explicit access or denial based decisions\n• Manage the rights to modify the audit events\n• Delete the group with read access to the audit records\n• Modify the group with read access to the audit records\n• Add the group with read access to the audit records\n\nThe types of Administrators are described in the following sections.\n\n9.1.4.1 Security Administrator\nThe security administrator:\n\n• Is responsible for implementing and maintaining system security\n• Defines users, resources, access levels, and facilities\n• Controls the security environment by using control options and TSS commands\n• Monitors resource access violations with the auditing, tracking, and reporting options\n\nThe security administrator's role is determined by:\n\n• The scope of authority (the entire installation or a single department within that installation)\n• The designated administrative authorities (create ACIDs, run reports, change control options)\n\nNote: Each security administrator must first possess the appropriate administrative authority.\n\n9.1.4.2 Types of Security Administrators\nThe CA Top Secret administrative hierarchy has seven levels. The first six levels represent ACIDs whose primary function is to control security administration.\n\n• Master Security Control ACID (MSCA) - Referred to as the Master Central Security Administrator. There can be only a single MSCA. The MSCA’s ACID is pre-defined; it exists as soon as the Security File is created through TSSMAINT.\nThe MSCA’s ACID cannot be deleted, although it can be renamed. An MSCA has unlimited scope. Only an MSCA has implicit unlimited administrative authority. Only the MSCA can create SCAs. The MSCA can log on or initiate with only password checking in force; no expiration, facility, source, or terminal checking is performed by CA Top Secret.\n\n- **Central Security Control ACID (SCA)** - Referred to as the Central Security Administrator. An SCA is not associated with any specific zone division or department but has unlimited scope. An SCA, with this authority, can do almost everything except define another SCA.\n\n- **Limit Central Security Control ACID (LSCA)** - An LSCA is not associated with any specific zone, division, or department. It has the same capabilities as an SCA but rules of scope checking apply.\n\n- **Zonal Control ACID (ZCA)** - Only a central security administrator can establish zonal administrators. Each ZCA is associated with a particular zone. A ZCA can perform the following activities:\n - administrative tasks for the **divisions** linked to this zone\n - administrative tasks for the **departments** linked to this zone\n - administrative tasks for the **users** linked to this zone\n - administrative tasks for the **profiles** linked to this zone\n\nA zone may have several ZCAs, or under a centralized administrative system, no ZCAs. In the latter case, a central security administrator must perform the administrative requirements for this zone.\n\n- **Divisional Control ACID (VCA)** - A central security administrator can establish divisional administrators. Each VCA is associated with a particular division. A VCA can perform the following activities:\n - administrative tasks for the **departments** linked to this division\n - administrative tasks for the **users** linked to this division\n - administrative tasks for the **profiles** linked to this division\n\nA division may have several VCAs, or under a centralized administrative system, no VCAs. In the latter case, central security administrator or ZCA must perform the administrative requirements for this division.\n• **Departmental Control ACID (DCA)** - Departmental administrators can be established by a central security administrator or a VCA for a department that is linked to that VCA's division. The responsibilities that can be performed by a DCA include the following activities:\n \n o administrative tasks for the **users** that belong to this department\n \n o administrative tasks for the **profiles** that belong to this department\n\nA department may have several DCAs or no DCAs. In the latter case the administrative requirements for this department have to be performed by either a central security administrator or the appropriate ZCA or VCA.\n\n9.1.4.3 **Auditor**\n\nAs with any other type of administrator, an auditor’s scope is a function of the TYPE that was designated at ACID creation, for example, TYPE(VCA). A central auditor is defined as an SCA; a divisional auditor is defined as a VCA.\n\n9.1.4.4 **Command Functions**\n\nCommand functions are the primary tool of the security administrator. A command function lets an administrator define ACIDs, assign attributes, and determine resource access. Commands have the following syntax:\n\n```\nTSS FUNCTION(acid|STC|AUDIT|RDT|FDT|DLF|ALL|NDT|SDT)\nKEYWORD(OPERAND)\n```\n\nThe following definitions apply for command functions:\n\n- **TSS** – CA Top Secret commands must always begin with “TSS.”\n- **FUNCTION** – Specifies the name of the function CA Top Secret will perform. The following rules apply:\n o The function must immediately follow \"TSS.\"\n o Only one function can be entered per TSS command.\n o One or more spaces must be entered between TSS and the function.\n- **(acid|STC|AUDIT|RDT|FDT|DLF|ALL|NDT|SDT)** – Specifies the ACID or record the function will affect.\n• KEYWORD - Specifies the resource type or security attribute the function is processing. Keywords can be entered:\n o In any order\n o Online: Keywords can be entered from line to line without special action.\n o In batch: The last keyword must follow on a continuing line with a blank and a dash. The next keyword can be entered on the next input line.\n\n• (OPERAND) - Specifies the prefix, resource name, or the required value for a security attribute. Operands must be provided, and parentheses must be provided to indicate no value. If an operand is missing, any following keyword is ignored.\n\nCA Top Secret functions can be entered free form onto the command screen of an online terminal or into any of the CA Top Secret full-screen administration panels.\n\nCA Top Secret provides online status information on the security environment and the ACIDs and resources within that environment. The informational TSS commands are:\n\n• TSS LIST - Displays information on individual or reserved ACIDs (such as the RDT).\n• TSS WHOHAS - Displays information on a resource, field name (FDT), facility, attribute or administrative authority, depending on which is specified.\n• TSS WHOOWNS - Displays information on whether a resource is defined to CA Top Secret and who is the owner.\n• TSS WHOAMI - Displays information on the security environment for the ACID currently signed on to the terminal.\n• TSS MODIFY STATUS - Displays information on the global security environment and control options currently in effect.\n\n9.1.4.5 Command Propagation Facility\n\nIn addition to propagating changes, the Command Propagation Facility (CPF) allows administrators to view the contents of the CA Top Secret Security Database from other nodes. The viewing is completely secure since the administrator’s scope is verified at both locations, allowing the administrator to review the security information for which he or she is responsible for at all nodes in the CPF domain.\n\nCPF propagated administration executes on the remote system using the authority of the administrator as defined in the remote system, and not using the authority and scope of the administrator from the originating system. For example, if a security administrator on one system propagates a CA Top Secret command to a system where that administrator is not defined as a security administrator, then the command is limited to the non-security administrator authority. It should also be noted in regards to data propagation that user-initiated password changes at system entry that are propagated using CPF cause the user’s password to change at each node where the change is sent.\n9.1.5 TOE Access\n\nCA Top Secret has the ability to allow or deny session establishment based upon certain configured settings. Access can be allowed or denied depending on the time or date, source, or APPLID. Additionally, an attempt to establish a session can be denied if the user account has been suspended.\n\nSuspension of an account can occur for several reasons. The first being inactivity of the account. Users with the appropriate privilege can configure the inactivity period length through TSS MODIFY INACTIVE (1-255). This determines the number of days an account must be inactive before being suspended. A user with the appropriate privileges can suspend ACIDs until manually removed or for a limited time. An ACID will also get suspended if the password violation threshold is reached.\n\nFor the time or date setting, session establishment can be denied for instances such as holidays, weekends, or after hours. For instance, with proper configuration, the TOE can deny session establishment for Friday and Saturday or after the workday has ended.\n\nThe source and APPLID can be denied as well to ensure that the TOE only allows communication and sessions from those locations it trusts. This can be by a specific terminal ID, IP address, Point of Entry, or from the application by which a user is trying to authenticate.\n9.2 Self Protection (ADV_ARC.1)\n\nThe TOE forces users/administrators to authenticate to it prior to allowing them to take any actions on objects which the TOE protects within the operational environment. This includes the TOE’s configuration files and processes. The TOE also forces the users/administrators to authenticate in a manner consistent with administrative defined policies. These policies include the authentication mechanisms that need to be utilized and any access restrictions that need to be placed against their ability to authenticate. The TOE will also suspend the ability of users/administrators to successfully authenticate to the TOE due to a consecutive number of failed authentication attempts based on ACID. This assists in protecting the TOE from a potential unauthorized user. In addition, the TOE enforces strong secrets according to administrative defined policies, which further prevents unauthorized users from successfully authenticating to the TOE.\n\nOnce users/administrators are authenticated, the TOE maintains individual sessions associated with them through the creation of a security environment, which is associated with their ACID. Each security environment defines the authorizations that the associated user/administrator has to perform operations on objects. The TOE protects these security environments such that a process of another user/administrator cannot affect the contents of each individual security environment.\n\nThe TOE monitors all requests from subjects within its operational environment, including requests from users/administrators, OS processes, and system processes. The TOE determines which requests will be authorized to be performed. Therefore, the TOE has the ability to monitor actions by subjects external to itself on its own configuration files and processes. The TOE’s access control policies only allow those actions which are defined to be actions from a trusted subject.\n\nThe TOE also ensures that information critical for the security of subjects is protected via the operational environment’s cryptographic mechanisms. The TOE will call the z/OS ICSF module when the TOE determines that security relevant information should be encrypted before being stored in the operational environment or sent outside the TOE’s security perimeter.\n\nThe TOE records log data in two potential locations. SMF, which is a system level file, stores the information and receives security protection preventing deletion access. The second file, Audit and Tracking file (or ATF), is a file that is attached to the TOE’s address space. The file is in constant use and is also protected from deletion access. Additionally, the data collected cannot be removed without being overwritten. This requires system knowledge and the significant level of access.\n9.3 **TOE Summary Specification Rationale**\n\nThis section identifies the security functions provided by the TOE mapped to the security functional requirement components contained in this ST. This mapping is provided in the following table.\n\n<table>\n<thead>\n<tr>\n<th>Security Function</th>\n<th>Security Functional Components</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Security Audit (FAU)</td>\n<td>FAU_GEN.1 Audit data generation</td>\n</tr>\n<tr>\n<td></td>\n<td>FAU_GEN.2 User identity association</td>\n</tr>\n<tr>\n<td></td>\n<td>FAU_SAR.1 Audit review</td>\n</tr>\n<tr>\n<td></td>\n<td>FAU_SAR.2 Restricted audit review</td>\n</tr>\n<tr>\n<td></td>\n<td>FAU_SEL.1 Selective audit</td>\n</tr>\n<tr>\n<td>User Data Protection (FDP)</td>\n<td>FDP_ACC.2(1) Complete access control</td>\n</tr>\n<tr>\n<td></td>\n<td>FDP_ACC.2(2) Complete access control</td>\n</tr>\n<tr>\n<td></td>\n<td>FDP_ACF.1(1) Security attribute based access control</td>\n</tr>\n<tr>\n<td></td>\n<td>FDP_ACF.1(2) Security attribute based access control</td>\n</tr>\n<tr>\n<td>Identification and Authentication (FIA)</td>\n<td>FIA_AFL.1 Authentication failure handling</td>\n</tr>\n<tr>\n<td></td>\n<td>FIA_ATD.1 User attribute definition</td>\n</tr>\n<tr>\n<td></td>\n<td>FIA_SOS.1(1) Verification of secrets</td>\n</tr>\n<tr>\n<td></td>\n<td>FIA_SOS.1(2) Verification of secrets</td>\n</tr>\n<tr>\n<td></td>\n<td>FIA_SOS.2 TSF generation of secrets</td>\n</tr>\n<tr>\n<td></td>\n<td>FIA_UAU.2 User authentication before any action</td>\n</tr>\n<tr>\n<td></td>\n<td>FIA_UAU.4 Single-use authentication mechanisms</td>\n</tr>\n<tr>\n<td></td>\n<td>FIA_UAU.5 Multiple authentication mechanisms</td>\n</tr>\n<tr>\n<td></td>\n<td>FIA_UID.2 User identification before any action</td>\n</tr>\n<tr>\n<td></td>\n<td>FIA_USB.1 User-subject binding</td>\n</tr>\n<tr>\n<td>Security Management (FMT)</td>\n<td>FMT_MOF.1(1) Management of security functions behavior</td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_MOF.1(2) Management of security functions behavior</td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_MOF.1(3) Management of security functions behavior</td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_MOF.1(4) Management of security functions behavior</td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_MSA.1 Management of security attributes</td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_MSA.3 Static attribute initialization</td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_SMF.1 Specification of management functions</td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_SMR.1 Security roles</td>\n</tr>\n</tbody>\n</table>\nSecurity Function | Security Functional Components\n-------------------|----------------------------------\nTOE Access (FTA) | FTA_TSE.1 TOE session establishment\n\nTable 9-7: Security Functional Components\n\n9.3.1 Security Audit\n\nThe audit function of the TOE enforces the FAU_GEN.1, FAU_GEN.2, FAU_SAR.1, FAU_SAR.2, FAU_SAR.3, and FAU_SEL.1 requirements.\n\nSection 9.1.1 details how the TOE collects security and system audit information. Administrators with proper privileges are able to monitor, alert, and report information about user activity across platforms.\n\nThe examination of the TSS showed that each of these requirements were successfully mapped to the SFRs listed above the information provided in the ST introduction.\n\nThe generation of audit records (FAU_GEN.1.1) is provided in Section 2.5.1 as well as in the TSS, Section 9.1.1. In addition to the generation of audits, the AUDIT privilege is discussed in section 9.1.1.1 to explain the use of the privilege in order to view the audited information. FAU_GEN.1.2 is then fulfilled in Section 9.1.1.2 with the mapping of information audited in relation to the event that is occurring. Section 2.5.1 of the introduction covers this information as well but in less detail.\n\nFAU_SAR.1 and FAU_SAR.2 are covered in the TSS, Sections 9.1.1.1 and 9.1.1.2. These sections discuss the types of reports/logs that are provided in the TOE as well as the AUDIT privilege. These sections demonstrate the use of scoping (the AUDIT privilege) to apply restrictions on auditing. Finally, FAU_SEL.1 is covered in Section 9.1.1 with the discussion of the customization of reports in relation to the preferences of the users on the system.\n\n9.3.2 User Data Protection\n\nThe User Data Protection function of the TOE enforces the FDP_ACC.2(1), FDP_ACC.2(2), FDP_ACF.1(1), and FDP_ACF.1(2) requirements.\n\nMLS is a security policy in CA Top Secret that provides discretionary access control (DAC) protection mechanisms and includes mandatory access control (MAC). MLS is an optional layer of protection on top of DAC, which forces security classifications, called security labels, for virtually all users, data and resources in a system. Additionally, it validates all access based on these labels, regardless of permissions and ownership. MLS offers selective protection of data and resources based on a user’s organization’s individual needs. CA Top Secret lets a user activate MLS and implement security labels for the users, resources, and data that require a higher level of security.\n\nMAC imposes a security policy based on security labels. Security labels classify users, data, and resources. Standard permissions still apply but only after MAC label dominance\nchecks determine that a user can access data and resources based on their security label and the security label of the data or resources the user wants to access.\n\nThe purpose of MAC is to prevent the system from allowing data with a high sensitivity security label from being disclosed to a user with a lower sensitivity security label. For example, a user with a high sensitivity security label cannot send a highly sensitive data set to a user with a lower sensitivity security label. These are known as the “simple security property” and the “confinement property” or “write-down” protection.\n\nIn an MLS system, after an authorized user enters the system, data or system resources can be accessed based on whether the organization or other system users want to share data. CA Top Secret DAC security policy manages the controlled sharing of data and resources using rules. Depending on an implementation option, a security administrator or data owner can write rules to permit sharing. If a user tries to access data without permission, the system creates a violation record and denies access.\n\nAn MLS system ensures that no user or program can scavenge data from an object after it has been deleted. Object reuse protection ensures that when a user deletes a data set, the data set is actually erased. Without object reuse protection, the storage would be returned to the storage pool without erasure. A user who obtained storage for a new data set could read the storage and find out what the previous user had put in the data set.\n\n9.3.3 Identification and Authentication\n\nThe identification and authentication function of the TOE enforces the FIA_AFL.1, FIA_ATD.1, FIA_SOS.1(1), FIA_SOS.1(2), FIA_SOS.2, FIA_UAU.2, FIA_UAU.4, FIA_UAU.5, FIA_UID.2, and FIA_USB.1 requirements.\n\nCA Top Secret uses the ACID record to verify a user’s system access and privileges. Section 2.5.2 of the introduction discusses the basic overview of the Identification and Authentication requirements and is covered in more detail in the sections of the TSS discussed below.\n\nSection 9.1.2 discusses the primary of attributes for users with the use of the security file. The security file is responsible for storing the security attributes which are relevant to all users of the TOE. This information supports the FIA_ATD.1 requirement.\n\nFIA_SOS.1(1) is fulfilled in Sections 9.1.2.5 and 9.1.2.5.1 with the discussion of the password policy and requirements for password defaults. FIA_SOS.1(2) is then fulfilled in Section 9.1.2.5.2 with the policies relating to a user’s passphrase.\n\nFIA_AFL.1.1 and FIA_AFL.1.2 is fulfilled by Section 9.1.2.5 with the information regarding the suspension of user accounts when too many attempts are made to connect to the TOE with invalid information.\n\nFIA_UID.2, FIA_USB.1, and FIA_UAU.2 are fulfilled in Section 9.1.2 with the discussion of authentication before any action and authentication methods provided by\nthe TOE which are chosen by the application. Additionally, the TSS speaks at length about a user being associated with the attributes attached to their roles.\n\nSection 9.1.2.3 fulfills the FIA_UAU.4 requirement where it speaks to passticket authentication. FIA_UAU.5 is fulfilled with Sections 9.1.2.1/2/3/4/5/7/8/9. These sections cover the five methods of authentication that can be used when accessing the TOE. These methods include passwords, passphrases, certificates, passtickets, and Kerberos.\n\n### 9.3.4 Security Management\n\nThe security management function of the TOE enforces the FMT_MOF.1(1), FMT_MOF.1(2), FMT_MOF.1(3), FMT_MOF.1(4), FMT_MSA.3, FMT_SMF.1, and FMT_SMR.1 requirements.\n\nSecurity management is required to manage the users, groups and the privileges of users. This is supporting identification and authentication as well as access control. Different aspects of security management support each other. For example, user and group management supports the management of access control, because the definition of access rights can be simplified by defining access on a group level and assign users that require access to the appropriate groups. Security management also supports auditing because it allows to define the events to be audited based on individual users, individual protected objects, privileges of the users, type of event, and (in LSPP mode) security label.\n\nIn addition, the security management of the audit data (especially dumping the SMF data sets when they get full) also supports audit. Security management also includes the management of access rights including (in LSPP mode) the definition of the security labels and the definition how they get printed on a printer that supports multiple labels. The management of discretionary access rights can be performed by users with the required privileges and the management of those privileges is part of the user and group management. This structure allows delegation of some management functions to users with privileges limited to the scope of a group. Security management also includes the management of access rights including (in LSPP mode) the definition how they get printed on a printer that supports multiple labels. The management of discretionary access rights can be performed by users with the required privileges and the management of those privileges is part of the user and group management. This structure allows delegation of some management functions to users with privileges limited to the scope of a group. Security management also supports communication security by providing the ability to configure the different protection mechanisms SSL/TLS, IPSec, SSH, Kerberos, and ATTLS.\n\nSection 2.5.3 of the introduction discusses a general overview of the Security Management requirements as shown above and is expounded upon in the TSS.\n\nThe security management requirements outlined by the TOE are covered by the TSS in Section 9.1.1.4. The main paragraph of this section identifies the division of roles into Security Administrators Scoped Security Administrators, and Users. These roles can be scoped based on privileges and allow for variations of the default roles. This applies to FMT_MOF.1(1), FMT_MOF.1(2), FMT_MOF.1(3), and FMT_MOF.1(4). These SFRs apply to the security administrator, user, and scoped security administrator. Section 9.1.4.3, Scope, also addresses the FMT_MOF.1 requirements by detailing how scope is used to enforce different levels of privileges for users of the TOE.\nFollowing FMT_MOF.1, the requirements for FMT_MSA.1 are fulfilled in Section 9.1.4.1 of the TSS with discussion of the privileges for the previously discussed roles. FMT_MSA.3 is then fulfilled by Section 9.1.3.2 with the discussion of the default values and how they can be changed on the TOE.\n\nFMT_SMF.1 is fulfilled again by Section 9.1.4.1 as well as with Section 9.1.4.4. 9.1.4.4 discusses the types of roles provided to users and what privileges apply to those roles. These can then be mapped to Section 9.1.4.1 to further detail what these roles can perform on the TOE. Finally, FMT_SMR.1 is covered by the same two sections.\n\n### 9.3.5 TOE Access\n\nThe TOE access function of the TOE enforces the FTA_TSE.1 requirement.\n\nThis requirement is fulfilled by Section 2.5.5 of the introduction by discussing the denial of a session based on a user’s status or failure to authenticate correctly. Section 9.1.5 and 9.1.5.1 further detail this information with a more in-depth look at the suspension of a user account when on vacation or when the authentication attempt limit is surpassed.\n10 Security Problem Definition Rationale\n\n10.1 Security Objectives Rationale\n\nThe following table provides a mapping with rationale to identify the security objectives that address the stated assumptions and threats.\n\n<table>\n<thead>\n<tr>\n<th>Assumption</th>\n<th>Objective</th>\n<th>Rationale</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>A.ADMIN</td>\n<td>OE.ADMIN</td>\n<td>OE.ADMIN maps to A.ADMIN in order to ensure that authorized administrators install, manage and operate the TOE in a manner that maintains its security objectives.</td>\n</tr>\n<tr>\n<td>A.PATCHES</td>\n<td>OE.ADMIN</td>\n<td>OE.ADMIN maps to A.PATCHES in order to ensure that the authorized administrators properly patches the Operational Environment and the TOE in a manner that maintains the security objectives of the TOE.</td>\n</tr>\n<tr>\n<td>A.NOEVIL</td>\n<td>OE.NOEVIL</td>\n<td>OE.NOEVIL maps to A.NOEVIL in order to ensure that there are no careless, willfully negligent, or hostile administrators of the TOE.</td>\n</tr>\n<tr>\n<td>A.LOCATE</td>\n<td>OE.LOCATE</td>\n<td>OE.LOCATE maps to A.LOCATE in order to ensure that physical security is provided in the environment where the TOE operates.</td>\n</tr>\n</tbody>\n</table>\n\nTable 10-1: Assumption to Objective Mapping\n<table>\n<thead>\n<tr>\n<th>Threat</th>\n<th>Objective</th>\n<th>Rationale</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>T.ACCESS</td>\n<td>Unauthorized users could gain access to objects protected by the TOE that they are not authorized to access.</td>\n<td>O.ACCESS The TOE will provide measures to authorize users to access objects protected by the TOE once the user has been authenticated. User authorization is based on access rights configured by the authorized users of the TOE.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>O.ACCESS (FDP_ACC.2(1), FDP_ACC.2(2), FDP_ACF.1(1), FDP_ACF.1(2)) addresses T.ACCESS by providing the authorized users with the capability to specify access restrictions on the objects protected by the TOE to authorized users.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>OE.EAVESDROPPING addresses T.ACCESS by ensuring that the underlying Operating System provides the capability to encrypt TSF data used by the TOE.</td>\n</tr>\n<tr>\n<td>T.ADMIN_ERROR</td>\n<td>An administrator may incorrectly install or configure the TOE, or install a corrupted TOE resulting in ineffective security mechanisms.</td>\n<td>O.ROBUST_ADMIN_GUIDANCE The TOE will provide administrators with the necessary information for secure delivery and management.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>O.ROBUST_ADMIN_GUIDANCE (ALC_DEL.1, AGD_PRE.1, AGD_OPE.1) helps to mitigate T.ADMIN_ERROR by ensuring the TOE administrators have guidance that instructs them how to administer the TOE in a secure manner and to provide the administrator with instructions to ensure the TOE was not corrupted during the delivery process. Having this guidance helps to reduce the mistakes that an administrator might make that could cause the TOE to be configured in a way that is unsecure.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>O.MANAGE The TOE will provide authorized administrators with the resources to manage and monitor user accounts, objects, and security information relative to the TOE.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>O.MANAGE (FMT_MOI.1(1), FMT_MOI.1(2), FMT_MOI.1(3), FMT_MOI.1(4), FMT_MSA.1, FMT_MSA.3, FMT_SMF.1, FMT_SMR.1) addresses T.ADMIN_ERROR by ensuring only authorized administrators can use the provided resources for managing and monitoring user accounts, objects, and security information relative to the TOE.</td>\n</tr>\n<tr>\n<td>Threat</td>\n<td>Objective</td>\n<td>Rationale</td>\n</tr>\n<tr>\n<td>----------------------</td>\n<td>---------------------------------------------------------------------------</td>\n<td>---------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>T.AUDIT_COMPROMISE</td>\n<td>A malicious user or process may view audit records, cause audit records to be lost or modified, or prevent future audit records from being recorded, thus masking a user’s action.</td>\n<td>O.ACCESS (FDP_ACC.2(1), FDP_ACC.2(2), FDP_ACF.1(1), FDP_ACF.1(2)) addresses T.AUDIT_COMPROMISE by providing the authorized users with the capability to specify access restrictions on the objects protected by the TOE.</td>\n</tr>\n<tr>\n<td>T.MASK</td>\n<td>Users whether they be malicious or non-malicious, could gain unauthorized access to the TOE by bypassing identification and authentication countermeasures.</td>\n<td>O.AUDIT (FAU_GEN.1, FAU_GEN.2, FAU_SAR.1, FAU_SAR.2, FAU_SEL.1) addresses T.MASK by providing the authorized users with tools necessary to monitor user activity to ensure that misuse of the TOE does not occur.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>O.SYSTIME helps to mitigate T.MASK by ensuring the accuracy of the tools necessary to monitor user activity as provided via O.AUDIT.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>O.ROBUST_TOE_ACCESS (FIA_AFL.1, FIA_UAU.2, FIA_UAU.4, FIA_UAU.5, FIA_ACID.2, FTA_TSE.1), addresses T.MASK by controlling the logical access to the TOE and the objects the TOE protects. By constraining how and when authorized users can access the TOE, and by mandating the type and strength of the authentication scheme, this objective helps mitigate the possibility of a user attempting to login and masquerade as an authorized user. In addition, this objective provides the administrator the means to control the number of failed login attempts a user can generate before an account is suspended, further reducing the possibility of a user gaining unauthorized access to the TOE.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>O.AUTH (FIA_ATD.1, FIA_SOS.1(1), FIA_SOS.1(2), FIA_SOS.2, FIA_UAU.2, FIA_UAU.4, FIA_UAU.5, FIA_UAU.6) provides the TOE with measures to uniquely identify all users and administrators. The TOE will authenticate the claimed identities of users and administrators to ensure that only authorized users are allowed to access the TOE.</td>\n</tr>\n</tbody>\n</table>\n\nBooz Allen Hamilton CCTL – CA Proprietary Page 113\nThreat | Objective | Rationale\n--- | --- | ---\nIdentity prior to granting a user or administrator access to the objects protected by the TOE. | FIA_UID.2, FIA_USB.1) addresses T.MASK by providing measures to uniquely identify and authenticate users to the TOE through multiple authentication methods. In addition, this objective ensures that the strength of user’s password or passphrase meets a scheme which ensure that unauthorized users cannot easily impersonate an authorized user by guessing their password.\n\nTable 10-2: Threat to Objective Mapping\n\n10.2 Security Functional Requirements Rationale\n\nThe following table provides a mapping with rationale to identify the security functional requirement components that address the stated TOE and environment objectives.\n\n<table>\n<thead>\n<tr>\n<th>Objective</th>\n<th>Security Components</th>\n<th>Functional Requirements</th>\n<th>Rationale</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>O.ACCESS The TOE will provide measures to authorize users to access objects protected by the TOE once the user has been authenticated. User authorization is based on access rights configured by the authorized users of the TOE.</td>\n<td>FDP_ACC.2(1) Complete access control</td>\n<td>FDP_ACC.2(1) states the TSF shall enforce the Discretionary Access Control Policy on users requesting access to protected objects within the Operational Environment.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FDP_ACC.2(2) Complete access control</td>\n<td>FDP_ACC.2(2) states the TSF shall enforce the Mandatory Access Control Policy on users requesting access to protected objects within the Operational Environment.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FDP_ACF.1(1) Security attribute based access control</td>\n<td>FDP_ACF.1(1) states the TSF shall enforce the Discretionary Access Control Policy on users requesting access to objects based on the security attributes defined in Table 7-5, as well as, resource class name and entity name</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FDP_ACF.1(2) Security attribute based access control</td>\n<td>FDP_ACF.1(2) states the TSF shall enforce the Mandatory Access Control Policy on users requesting access to objects based on AccessLevel, Type, Object Security Label, and Subject Security label.</td>\n<td></td>\n</tr>\n<tr>\n<td>Objective</td>\n<td>Security Components</td>\n<td>Functional Components</td>\n<td>Rationale</td>\n</tr>\n<tr>\n<td>--------------</td>\n<td>---------------------</td>\n<td>-----------------------</td>\n<td>------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>O.AUDIT</td>\n<td>FAU_GEN.1 Audit data generation</td>\n<td>FAU_GEN.1 states that the TSF shall be able to generate an audit record for the start-up and shutdown of the audit functions and all auditable events between subjects and resources. For each record, the TSF shall record the date/time/type/outcome of the event, the subject identity of the user which caused the event, the system ID, terminal ID, audit reason indicator, authority, mode, resource name, and if applicable the application or program that the user request was initiated from.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FAU_GEN.2 ACIDentity association</td>\n<td>FAU_GEN.2 states the TSF shall be able to associate each auditable event with the identity of the user that caused the event.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FAU_SAR.1 Audit Review</td>\n<td>FAU_SAR.1 states the TSF shall provide the authorized user with the audit privilege with the capability to read all events collected in FAU_GEN.1 from the audit records within their scope.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FAU_SAR.2 Restricted audit review</td>\n<td>FAU_SAR.2 states the TSF shall prohibit all users read access to the audit records, except those users that have been granted explicit read-access.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FAU_SEL.1 Selective audit</td>\n<td>FAU_SEL.1 states that the TSF shall be able to select the events to be audited from the set of all auditable events based upon a Security Administrator’s selection of the event’s object identity, user identity, or permission.</td>\n<td></td>\n</tr>\n<tr>\n<td>O.AUTH</td>\n<td>FIA_ATD.1 User attribute definition</td>\n<td>FIA_ATD.1 specifies the security attributes that should be maintained at the level of the user. This means that the security attributes listed are assigned to and are changed at the level of the user. In other words, changing a security attribute (see</td>\n<td></td>\n</tr>\n<tr>\n<td>Objective</td>\n<td>Security Functional Components</td>\n<td>Rationale</td>\n<td></td>\n</tr>\n<tr>\n<td>-----------</td>\n<td>-------------------------------</td>\n<td>-----------</td>\n<td></td>\n</tr>\n<tr>\n<td>objects protected by the TOE.</td>\n<td>Table 7-5) associated with a user should have no impact on the security attributes of any other user.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>FIA_SOS.1(1) Verification of Secret</td>\n<td>FIA_SOS.1 states that the TSF shall enforce a password scheme that is sufficient to ensure that unauthorized users cannot easily impersonate an authorized user by guessing their password.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>FIA_SOS.1(2) Verification of Secret</td>\n<td>FIA_SOS.1 states that the TSF shall enforce a passphrase scheme that is sufficient to ensure that unauthorized users cannot easily impersonate an authorized user by guessing their passphrase.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>FIA_SOS.2 TSF Generation of Secrets</td>\n<td>FIA_SOS.2 states that the TSF shall enforce the password mechanism defined in FIA_SOS.1(1) to a Security Administrator defined NEWPW mask phrase which dictates the type of character accepted for each position in a password.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>FIA_UAU.2 User authentication before any action</td>\n<td>FIA_UAU.2 requires a user be authenticated before any access to the TOE and objects protected by the TOE is allowed.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>FIA_UAU.4 Single-use authentication mechanisms</td>\n<td>FIA_UAU.4 states that the TSF will prevent the reuse of a passticket for an authenticated session, which prevents an unauthorized user performing a replay attack with this authentication data.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>FIA_UAU.5 Multiple authentication mechanisms</td>\n<td>FIA_UAU.5 states that the TSF shall provide password, passphrase, passtickets, Kerberos, or digital certificates for authentication, and the TSF shall authenticate any user’s claimed identity according to the application from which the user is requesting system entry.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>FIA_UID.2 User identification before any action</td>\n<td>FIA_UID.2 requires a user be identified before any access to the TOE and objects protected by the TOE is allowed.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Objective</td>\n<td>Security Components</td>\n<td>Functional Components</td>\n<td>Rationale</td>\n</tr>\n<tr>\n<td>-----------</td>\n<td>---------------------</td>\n<td>-----------------------</td>\n<td>-----------</td>\n</tr>\n<tr>\n<td>FIA_USB.1 Binding</td>\n<td>User-Subject</td>\n<td>FIA_USB.1 requires the TOE to perform a binding of security attributes associated with users that are authenticated with the subjects that represent them in the TOE. The TOE will create a user’s ACID and security environment during this process.</td>\n<td></td>\n</tr>\n<tr>\n<td>O.MANAGE The TOE will provide authorized administrators with the resources to manage and monitor user accounts, objects, and security information relative to the TOE.</td>\n<td>FMT_MOF.1(1) Management of security functions behavior</td>\n<td>FMT_MOF.1(1) states the TSF shall restrict the ability to perform operations specified in Table 7-5 to the Security Administrator.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_MOF.1(2) Management of security functions behavior</td>\n<td>FMT_MOF.1(2) states the TSF shall restrict the ability to perform operations specified in Table 7-6 to the Scope Security Administrator based on their scope.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_MOF.1(3) Management of security functions behavior</td>\n<td>FMT_MOF.1(3) states the TSF shall restrict the ability to perform self password and passphrase changes to users.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_MOF.1(4) Management of security functions behavior</td>\n<td>FMT_MOF.1(4) states that users who own objects can perform all management functions on the object that are listed in Table 7-6.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>FMT_MSA.1 Management of security attributes</td>\n<td>FMT_MSA.1 states the TSF shall enforce the Mandatory Access Control and Discretionary Access Control policies to modify, delete, manage, add, control, or change the user attributes as listed in Table 7-5 to Security Administrators or Scoped Security Administrators within their scope.</td>\n<td></td>\n</tr>\n<tr>\n<td>Objective</td>\n<td>Security Components</td>\n<td>Functional Components</td>\n<td>Rationale</td>\n</tr>\n<tr>\n<td>---------------------------</td>\n<td>---------------------</td>\n<td>-----------------------</td>\n<td>---------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>FMT_MSA.3 Static attribute initialization</td>\n<td>FMT_MSA.3 states the TSF shall enforce the Mandatory Access Control and Discretionary Access Control policies to provide restrictive default values for security attributes that are used to enforce the SFP. It allows the Security Administrators or Scoped Security Administrators within their scope to override the default values set for security attributes when creating user accounts.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>FMT_SMF.1 Specification of management functions</td>\n<td>FMT_SMF.1 requires that the TOE provide the ability to manage its security functions as defined in Table 7-6.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>FMT_SMR.1 Security Roles</td>\n<td>FMT_SMR.1 requires the TOE to provide the ability to maintain the roles security administrator, scoped security administrator, and user. In addition, it requires that users be associated with these roles.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>O.ROBUST_ADMIN_GUIDANCE</td>\n<td>ALC_DEL.1 Delivery Procedures</td>\n<td>ALC_DEL.1 describes product delivery and a description of all procedures used to ensure objectives are not compromised in the delivery process.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>AGD_PRE.1 Preparative Procedures</td>\n<td>AGD_PRE.1 documents the procedures necessary and describes the steps required for the secure installation, generation, and start-up of the TOE.</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>AGD_OPE.1 Operational user guidance</td>\n<td>AGD_OPE.1 describes the proper use of the TOE from a user standpoint.</td>\n<td></td>\n</tr>\n<tr>\n<td>Objective</td>\n<td>Security Components</td>\n<td>Functional Components</td>\n<td>Rationale</td>\n</tr>\n<tr>\n<td>-------------------------</td>\n<td>---------------------</td>\n<td>-----------------------</td>\n<td>---------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>O.ROBUST_TOE_ACCESS</td>\n<td></td>\n<td>FIA_AFL.1 Authentication Failure Handling</td>\n<td>FIA_AFL.1 provides a detection mechanism for unsuccessful authentication attempts by users and administrators. The requirement enables a Security Administrator to set a threshold that prevents unauthorized users from gaining access to an authorized user’s account by guessing authentication data. Once the threshold is surpassed the TOE will suspend the targeted user’s ACID until the Security Administrator takes some action (e.g., un-suspends the account). Thus, limiting an unauthorized user’s ability to gain unauthorized access to the TOE.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>FIA_UAU.2 User authentication before any action</td>\n<td>FIA_UAU.2 requires a user be authenticated before any access to the TOE and objects protected by the TOE is allowed.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>FIA_UAU.4 Single-use authentication mechanisms</td>\n<td>FIA_UAU.4 states that the TSF will prevent the reuse of a passticket for an authenticated session, which prevents an unauthorized user performing a replay attack with this authentication data.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>FIA_UAU.5 Multiple authentication mechanisms</td>\n<td>FIA_UAU.5 states that the TSF shall provide password, passphrase, passtickets, Kerberos, or digital certificates for authentication, and the TSF shall authenticate any user’s claimed identity according to the application from which the user is requesting system entry.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>FIA_UID.2 User identification before any action</td>\n<td>FIA_UID.2 requires a user be identified before any access to the TOE and objects protected by the TOE is allowed.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>FTA_TSE.1 TOE session establishment</td>\n<td>FTA_TSE.1 states that the TOE will deny session establishment if the user is suspended, or if there is a policy that defines the date/time, source, and AppID where access is allowed and the user’s request does not adhere to the policy.</td>\n</tr>\n</tbody>\n</table>\n10.3 **EAL 4 Justification**\n\nThe threats that were chosen are consistent with attacker of medium attack potential, therefore EAL4 was chosen for this ST.\n\n10.4 **Requirement Dependency Rationale**\n\nAll Security Functional Requirement component dependencies have been met by the TOE as defined by the CC Part 2 with the exception of FPT_STM.1 and FMT_MTD.1.\n\nFPT_STM.1, Reliable Time Stamps is a dependency of FAU_GEN.1. This dependency is met by the Operational Environment. The underlying Operating System (z/OS) will be available to the TOE for use in determining the timestamp for the audit trail.\n\nFMT_MTD.1, Management of TSF Data is a dependency of FAU_SEL.1. The FMT_MTD.1 requirement has not been included in the ST because the TOE does not perform the management of data that is specific to the TSF. The data which the TOE allows users and administrators to perform management activities on is data that belongs to z/OS or the computing system, which has already been covered through the inclusion of the four iterations of FMT_MO.1. The data which is managed through the TOE is considered z/OS or computing system data because the TOE provides the ability to manage the security aspects of the subjects (i.e. users, administrators, applications) and objects (e.g. component of the computing or operating system, dataset, volume) which belong to the computing or operating system. Therefore, the inclusion of the FMT_MTD.1 requirement would not satisfy the intent of the requirement or the intent of the dependency.\n\n10.5 **Assurance Measures**\n\nThis section identifies the assurance measures provided by the developer in order to meet the security assurance requirement components for EAL4 augmented with ASE_TSS.2 and ALC_FLR.1. A description of each of the TOE assurance measures follows in Table 10-4.\n\n<table>\n<thead>\n<tr>\n<th>Component</th>\n<th>Document(s)</th>\n<th>Rationale</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ADV_ARC.1</td>\n<td>TOE Design Specification v1.0 IBM z/Architecture Principles of Operation CA Top Secret® for z/OS Control Options Guide r14 CA Top Secret® for z/OS Design Guide r14 z/OS Initial Program Load</td>\n<td>These documents describe the security architecture of the TOE and its underlying operating system.</td>\n</tr>\n<tr>\n<td>ADV_FSP.4</td>\n<td>Functional Specification v1.0 CA Top Secret® for z/OS Auditor Guide r14</td>\n<td>These documents describe the external interfaces to the TOE.</td>\n</tr>\n<tr>\n<td>Component</td>\n<td>Document(s)</td>\n<td>Rationale</td>\n</tr>\n<tr>\n<td>-----------</td>\n<td>-------------</td>\n<td>-----------</td>\n</tr>\n<tr>\n<td>ADV_IMP.1 Implementation Representation of the TSF</td>\n<td>CA Top Secret® for z/OS Compliance Information Analysis Guide r14</td>\n<td>These documents demonstrate the correspondence between source code and design documentation.</td>\n</tr>\n<tr>\n<td>ADV_TDS.3 Architectural Design</td>\n<td>CA Top Secret® for z/OS Auditor Guide r14</td>\n<td>These documents describe the internal design of the TOE.</td>\n</tr>\n</tbody>\n</table>\n\nThese documents provide guidance on how to use CA Top Secret.\n<table>\n<thead>\n<tr>\n<th>Component</th>\n<th>Document(s)</th>\n<th>Rationale</th>\n</tr>\n</thead>\n</table>\n| AGD_PRE.1 Preparative Procedures | CA Top Secret® for z/OS Installation Guide r14 \nCA Top Secret® for z/OS Implementation: Best Practice Guide r14 \nCA Top Secret® for z/OS Implementation: CICS Guide r14 \nCA Top Secret® for z/OS Implementation: IMS Guide r14 | These documents describe the setup procedures for CA Top Secret. |\n| ALC_CMC.4 Authorizations Controls | MF CM Plan Development \nMF CM Plan Documentation 2010 \nSTAR_Data_Sets \nSTAR_Transfer | These documents describe and demonstrate the implementation and documentation configuration management. |\n| ALC_CMS.4 CM Scope | CI list bookshelf TSS \nCI List Clarity TSS \nTop Secret EAL ALC_CMC file list 22 november | These documents demonstrate the CM scope of the TOE. |\n| ALC_DEL.1 Delivery Procedures | ALC_DEL_MF Security_Electronic Delivery and Installation | This document describes product delivery for CA Top Secret. |\n| ALC_DVS.1 Identification of Security Measures | MF CM Plan Development \nMF CM Plan Documentation \nSite inspection (folder with pictures) 2010.10.12 Onsite Assessment Report \n11-Backup_Procedure-GIS-2008Jun09 \n1619-GRC-Global_Security-Pre-employment_Screening-2008Apr05 \n1621 - GSAP \n3649-Access_Procedure-2007Jun29 \n5725-GRC-BP-C-RIM-Records_Security_and_Confidentiality_Policy-2008May23 | These documents define the vendor’s organizational security measures and provide verification that these measures are followed. |\n<table>\n<thead>\n<tr>\n<th>Component</th>\n<th>Document(s)</th>\n<th>Rationale</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ALC_FLR.1 Basic Flaw Remediation</td>\n<td>5727-GRC-BP-C-RIM-Records_Disposal_Procedure-2008May15</td>\n<td>These documents provide the policies for issuing new releases of the TOE as corrective actions.</td>\n</tr>\n<tr>\n<td></td>\n<td>5804-Privileged_Access-2008Jun24</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>7417-Enterprise_Procedure-Privacy_and_Data_Protection-2007Mar06</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>7705-Inactive_User_Account_procedure-2007Jun29</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>77260Server_Security_Procedure-2008Jun24</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>ALC_DVS CA Lisle Office_Building Security</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>ALC_DVS Lisle Information Brochure</td>\n<td></td>\n</tr>\n<tr>\n<td>ALC_LCD.1 Life-Cycle Definition</td>\n<td>5153-Project_360_Reference_Guide-2008Jul25</td>\n<td>This document provides the life-cycle definition of the TOE.</td>\n</tr>\n<tr>\n<td>ALC_TAT.1 Tools and Techniques</td>\n<td>ALC_TAT[1].1 Overview updated 23 november Assembler Reference Summary</td>\n<td>These documents describe the tools and techniques used in the development of the TOE.</td>\n</tr>\n<tr>\n<td>ASE_CCL.1 Conformance Claims</td>\n<td>CA Top Secret for z/OS r14 Security Target v1.1</td>\n<td>This document describes the CC conformance claims made by the TOE.</td>\n</tr>\n<tr>\n<td>ASE_ECD.1 Extended Components Definition</td>\n<td>CA Top Secret for z/OS r14 Security Target v1.1</td>\n<td>This document provides a definition for all extended components in the TOE.</td>\n</tr>\n<tr>\n<td>ASE_INT.1 Security Target Introduction</td>\n<td>CA Top Secret for z/OS r14 Security Target v1.1</td>\n<td>This document describes the Introduction of the Security Target.</td>\n</tr>\n<tr>\n<td>ASE_OBJ.2 Security Objectives</td>\n<td>CA Top Secret for z/OS r14 Security Target v1.1</td>\n<td>This document describes all of the security objectives for the TOE.</td>\n</tr>\n<tr>\n<td>ASE_REQ.2 Security Requirements</td>\n<td>CA Top Secret for z/OS r14 Security Target v1.1</td>\n<td>This document describes all of the security requirements for the TOE.</td>\n</tr>\n<tr>\n<td>ASE_SPD.1 Security Problem Definition</td>\n<td>CA Top Secret for z/OS r14 Security Target v1.1</td>\n<td>This document describes the security problem definition of the Security Target.</td>\n</tr>\n<tr>\n<td>ASE_TSS.2 TOE Summary Specification</td>\n<td>CA Top Secret for z/OS r14 Security Target v1.1</td>\n<td>This document describes the TSS section of the Security Target.</td>\n</tr>\n<tr>\n<td>Component</td>\n<td>Document(s)</td>\n<td>Rationale</td>\n</tr>\n<tr>\n<td>----------------</td>\n<td>-----------------------------------------------------------------------------</td>\n<td>---------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>ATE_COV.2</td>\n<td>TSSAUDIT, TSSCFI LE_Testplan, TSSCHART_TESTPLAN, TSSCPR, TSSOE RPT_TESTPLAN,</td>\n<td>These documents demonstrate functional test coverage for the TOE.</td>\n</tr>\n<tr>\n<td>Component</td>\n<td>Document(s)</td>\n<td>Rationale</td>\n</tr>\n<tr>\n<td>----------------------------</td>\n<td>-----------------------------------------------------------------------------</td>\n<td>------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>ATE_FUN.1 Functional Testing</td>\n<td>System Configuration (folder) TSSAUDIT TSSCPF_TESTPLAN TSSCHART_TESTPLAN TSSCPR TSSOERPT_TESTPLAN TSSPROT_TESTPLAN TSSRCVR_backup test TSSREPORTS_TESTPLAN TSSrptst_TESTPLAN TSSTrack test plans TSSUTIL Test Plans Autoerase CICS_TESTPLAN MLTESTPLAN SYSTEMENTRYTESTPLAN TSS_IMS Test Plan TSSCPF TEST PLAN Kerberos Test Plan OutBound_LDS-LDAP TestPlan PassPhrase PassTicket Testing Base Certificate Testing TSS_PASSWORD_TESTPLAN Administrator SECURITY MANAGEMENT tss r14 beta1 checklist tss r14 beta2 checklist</td>\n<td>These documents demonstrate the format of functional testing and provide evidence of its completeness.</td>\n</tr>\n<tr>\n<td>ATE_IND.2 Independent Testing</td>\n<td>Booz Allen Hamilton Independent Functional Test Plan TSS System Configuration Test Output (folder) Test Recordings (folder)</td>\n<td>These documents outline the tests the evaluators executed to verify the correctness of the functional testing as well as the state of the system prior to the testing. They also provide evidence of the data reviewed during independent functional testing to demonstrate that the tests completed appropriately.</td>\n</tr>\n<tr>\n<td>AVA_VAN.3 Focused Vulnerability Testing</td>\n<td>Booz Allen Hamilton Vulnerability Test Plan Test Batch Jobs Wireshark Trace Test Output (folder)</td>\n<td>These documents outline the vulnerability research performed and the tests which were used in order to attempt to tamper with or bypass the operational TOE. It also contains a record of the specific batch jobs run to complete the testing as well as the system outputs of these test activities.</td>\n</tr>\n</tbody>\n</table>\n\nTable 10-4: Assurance Requirements Evidence"}}},{"rowIdx":62,"cells":{"id":{"kind":"string","value":"46744b86b28c17edc6cfee93ed4da5af447ac87c"},"text":{"kind":"string","value":"Performance tuning of object-relational applications\n\nZahra Davar\nUniversity of Wollongong\n\nUNIVERSITY OF WOLLONGONG\nCOPYRIGHT WARNING\n\nYou may print or download ONE copy of this document for the purpose of your own research or study. The University does not authorise you to copy, communicate or otherwise make available electronically to any other person any copyright material contained on this site. You are reminded of the following:\n\nThis work is copyright. Apart from any use permitted under the Copyright Act 1968, no part of this work may be reproduced by any process, nor may any other exclusive right be exercised, without the permission of the author.\n\nCopyright owners are entitled to take legal action against persons who infringe their copyright. A reproduction of material that is protected by copyright may be a copyright infringement. A court may impose penalties and award damages in relation to offences and infringements relating to copyright material. Higher penalties may apply, and higher damages may be awarded, for offences and infringements involving the conversion of material into digital or electronic form.\n\nUnless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.\n\nRecommended Citation\n\nResearch Online is the open access institutional repository for the University of Wollongong. For further information contact the UOW Library: research-pubs@uow.edu.au\nPerformance Tuning of Object-Relational Applications\n\nA thesis submitted in fulfillment of the requirements for the award of the degree\n\nMaster of Computer Science - Research\n\nfrom\n\nUNIVERSITY OF WOLLONGONG\n\nby\n\n(Mina) Zahra Davar\n\nSchool of Computing and Information Technology\nNovember 2015\n© Copyright 2015\n\nby\n\n(Mina) Zahra Davar\n\nAll Rights Reserved\nDedicated to\nMy mother and my father and my two beautiful angels Runika and Melody\nDeclaration\n\nThis is to certify that the work reported in this thesis was done by the author, unless specified otherwise, and that no part of it has been submitted in a thesis to any other university or similar institution.\n\n(Mina) Zahra Davar\nNovember 26, 2015\nAbstract\n\nOptimisation of object-relational database applications implemented as a combination of object-oriented and non-procedural code requires accurate balancing of the data-processing load between the client and the server sides. The large amounts of procedural code and less efficient, overly simple algorithms, lead to the majority of data processing to be performed on the client side. As a consequence it usually increases the amounts of transmitted data to the client and the amount of time required to process the data by the client.\n\nThis thesis addresses the performance problem of object-oriented client-side applications that access data on the server through an object-oriented view of a relational database. To increase the performance of object-oriented applications, a collection of transformation rules are introduced to replace the typical iterative structures of procedural code with the equivalent structures of non-procedural code. The rules can eliminate the iterations over classes of objects on the client side and can improve the balancing of the data processing load between the client and the server. This thesis shows how object-relational database applications can be optimised by using the proposed transformation rules. The correctness of the rules is proved by the Hoare logic formula. Software patterns proposed in this thesis can be used for the automatic optimisation of object-relational applications.\nI would like to express my sincere appreciation to the Faculty of Engineering and Information Sciences staff for all their support. I would particularly like to thank Prof. Aditya Ghose, for his help and encouragement and also A/Prof. Markus Hagenbuchner for his support and advice. This thesis would not have been possible without the ideas and the financial support from Dr. Janusz Getta.\n\nI would like to express my deepest gratitude to the Head of Postgraduate Study of the School Prof. Minjie Zhang for her useful advice during my study and also A/Prof. Lei Wang for his support during the thesis submission process.\n\nIn particular, I would like to thank two of my friends for their special contributions. Dr. Madeleine Strong Cincotta, for her assistance and feedback and friendly comments during writing my papers and thesis. Diane Coves, for her wonderful support and positive energy from the first day of my study at this University. To these two ladies: Thank you very much.\n\nI must thank all the members of the School of Computing and Information Technology, including the students. Special thanks to my lovely friends in our research lab, lab 239, for making such a friendly atmosphere for research and the enlightening discussions. I would like to especially thank Dr. Chao Yu(Roger), who was the most encouraging element in my research progress especially in the publishing of my first paper. Also, I would like to thank Sao Lan Leong (Marco), who is definitely one of the most motivated and intelligent people I’ve had the pleasure of chatting with.\n\nI would also like to thank Hongyu Liu, Leiting Chen and Handoko, the co-authors of my papers for their contribution and teamwork during the writing of the papers.\n\nLast but not least, to my husband: Thank you for your patience during the past two years and thank you for always being there for me.\n\n\nContents\n\nAbstract v\nAcknowledgement vi\nPublications vii\n\n1 Introduction 1\n 1.1 Research Gap ............................................. 3\n 1.2 Contributions of This Thesis ............................. 4\n\n2 Background 6\n 2.1 Overview ................................................. 6\n 2.2 Relational Databases and Relational Database Model .... 6\n 2.3 The OO Model ............................................. 7\n 2.4 The reasons for combining Relational Database Model and OO Model 7\n 2.5 Problem of Combining of the Relational Model and the OO model . 8\n 2.5.1 Impedance Mismatch ................................. 9\n 2.6 Solutions for Impedance Mismatch ........................ 10\n 2.6.1 OO Database Systems ............................... 10\n 2.6.2 The OR Database models ......................... 11\n 2.6.3 OR Mapping ........................................ 12\n 2.7 Modern OR Mapping Frameworks .......................... 12\n 2.7.1 LINQ ............................................. 13\n 2.7.2 Ruby on Rail .................................... 13\n 2.7.3 Hibernate ........................................ 14\n 2.7.4 Conclusion ....................................... 14\n 2.8 Previous works ......................................... 14\nList of Tables\n\n6.1 Analysis of Results ........................................... 88\nList of Figures\n\n1.1 Model of the distributed system ............................................ 2\n5.1 Apply patterns symbolically on an application step by step. ....... 59\n6.1 Execution Time for Application A ........................................... 71\n6.2 Number of Blocks-Read for application A .......................... 72\n6.3 Execution Time for Application B ........................................... 74\n6.4 Number of Blocks-Read for application B ......................... 75\n6.5 Execution Time for Application C ........................................... 79\n6.6 Execution Time for Application D ........................................... 81\n6.7 Execution Time for Application E ........................................... 83\n6.8 Execution Time for Application F ........................................... 85\nChapter 1\n\nIntroduction\n\nObject-relational mapping and efficient implementation of object-relational applications have received considerable attention, especially in business and commercial environments [Ors06]. The performance of object-relational applications is a serious challenge for programmers and database researchers [DD88]. Also, distributed information systems are becoming increasingly important for large organisations. At distributed system framework, query processing transfers data between computers in a network [RB13]. Therefore, performance tuning of object-relational applications in distributed information systems is considered another important challenge for research [Lop04].\n\nObject-relational database application is a typical client/server application [SIC98]. Object-relational mapping converts relational database systems (that are available on the server side) visible to an application programmer as a collection of classes of objects on the client side. This means that relational tables on the server side are wrapped into classes on the client side, so that objects and methods can be used on the client side as well. This is why object-relational database applications are always implemented in object-oriented programming language with embedded simple non-procedural statements of the object query language (OQL).\n\nApplication programmers access data on the client side through iterations over classes of objects from the results of processing of OQL statements. They typically focus on the logic of an application rather than data processing on the server side. Such an approach for the implementation of object-relational applications tends to reduce the amount of non-procedural code and to significantly simplify the code when accessing the object-oriented view of the database. The two main reasons leading to such performance problems are as follow:\nFirstly, the iterations over the large classes of objects on the client side require a transfer of large amounts of data from the server side. This is a procedure which is inefficient for large databases. Secondly, to process this data on the client side, the application programmer uses algorithms. These algorithms are not as efficient as the ones processing the same data on the server side. For example, as mentioned in an earlier paper [DG14], a traversal of an association on the client side is typically implemented as a join of two relational tables on the server side. The implementation of the join operation on the server side with hash-based or index-based algorithms is much more efficient than implementation of the same join operation on the client side with a simple nested loop algorithm.\n\nIn a distributed system the performance problem of object-relational applications is more critical than in a client-server system. The transmission of data in the client-server system is local whereas, in the distributed system, large amounts of data are transmitted over a wide network. However, there are some similarities between the performance problem of object-relational application in these two systems. In the distributed system, there is a class of distributed information systems. This class consists of a distributed and homogeneous database system on the source side and a global object-oriented view of data on the client side. The source database side includes relational database systems and the applications on the client side accesses data from the global object-oriented view of all distributed databases.\nFigure 1.1 illustrates the model of the distributed system. On the server side, there are some relational tables, such as A and B. The arrows show that the relational databases are transferred from the source database side to the client side as classes of objects so that object-oriented developers can access the data. In distributed systems, the object-oriented view of data on the global view side of the system allows application programmers to access the data through iterations over the classes of objects. Such an approach to implement user applications reduces the amount of non-procedural code required, when accessing data. Therefore, all of the data must be transferred from the source database side to an application that accesses the global view. As a result, the filtering conditions of the application will apply to all transferred data in the global view side. This leads to iterations over a large number of objects on the global view side, which is not efficient for large databases.\n\n1.1 Research Gap\n\nObject-oriented developers tend to write more procedural code. Using more procedural than non-procedural code in an object-oriented application, leaves more data-processing to the client. This default structure of object-oriented applications in the global view can affect the performance of both client-server and distributed systems [DG14]. At this point the performance implication in client-server systems and distributed systems, is the same.\n\nImplementing an efficient object-relational application can be performed by changing the balance of data-processing between the client and the server side. Shifting more amounts of data-processing to the server side leads to a reduction in the transmission of a large number of data from the server (source database side) to the client (global view side). This can be done by discovering the control structure of the program and rebuilding it with more non-procedural code rather than procedural code.\n1.2 Contributions of This Thesis\n\nThe solution presented in this thesis is based on the proper understanding of control structures of an application so that it can be rebuilt with more non-procedural code. By using this approach, each relational application written by a programmer can be rewritten in a way that achieves better performance. This means that only those objects which can satisfy the filtering conditions of the application are transferred from the server to the client.\n\nTo achieve this objective, first, several experiments were conducted with object-relational applications. The experiments were applied on different implementations of an application. The first version of each set of applications were based on what usually an object-oriented programmer uses with more procedural code rather than non-procedural code. The second version of the applications was based on using more non-procedural code. The performance of both versions of the applications in each of the sets, were recorded and compared.\n\nThe transformation rules, transform non-optimised version (input component) of the object-relational application into the optimised one (output component). By using transformation rules, procedural code from the input component is replaced with non-procedural statements in the output component. This centralizes most of the data processing on the server side. We considered three categories for transformation rules: Filtering, traversal of association and aggregation. The axioms and rules of the Hoare logic are used to prove the correctness of the rules. The problem of covering all possible cases of input components is solved by proposing certain software patterns. These patterns make the analysis of the source code easier. The combinations of proposed patterns can be used for complex applications.\n\nThis thesis, presents a set of transformation rules which can eliminate the iteration over a large number of objects. It speeds up the performance of the application by changing the control structures of an application. By applying the rules, some of the procedural components are replaced with non-procedural statements. As a result, a faster and more efficient performance of the application is achieved.\n1.2. Contributions of This Thesis\n\nThe significance of this thesis is that the proposed method improves some commonly used server-side operations thus reducing the server side load and response times. The adopted approach is very different to the existing approaches which commonly aim at improving efficiency through de-centralization (i.e. by moving some code to the client side) as in [Aga95] [RWD01].\n\nThe presented methodology supports most standard SQL/OQL functions such as Boolean expression (AND, OR) and comparison functions. The rules can be implemented in applications with a corresponding function which returns a value. The templates presented in Chapter 5 allow a more general class of predicates to enable the use of these rules.\n\nThe remainder of this thesis is organised as follows:\n\nChapter 2 presents background information on object-relational applications. In Chapter 3, the transformation rules are presented. Chapter 4 proves the correctness of the rules. Chapter 5 presents the software templates of the rules. Experimental results are presented in Chapter 6. Finally, Chapter 7 provides concluding remarks.\nChapter 2\n\nBackground\n\n2.1 Overview\n\nIn this section, different types of databases related to the topic of the thesis are presented. The relational database and relational database model were discussed and compared. Also, the OO model is discussed as a OO programming model which can merge with the relational model. Advantages and disadvantages of this combination are also discussed.\n\n2.2 Relational Databases and Relational Database Model\n\nRelational database management systems have been used in industry since the 1980s [CB01]. E. F. Codd, an IBM researcher, proposed the idea of a relational database model which became the basis for the implementation of relational database management systems. In the 1980s, the relational database systems revolutionised database management systems.\n\nIn relational databases, data is stored into two dimensional tables in rows and columns. The relationships among the data can be seen, by comparing the values stored in these tables. Structured query language (SQL) is used to retrieve and to manipulate data in the relational database model [MKF+03].\n\nThe tables available in OR mapping would be visible to OO programs as classes of objects. Therefore the access and retrieval of data needs iterations over the classes of objects. The normalisation of relational tables eliminates redundancy and this\nleads to the distribution of the data over many relational tables [Nic07]. Therefore in order to search these tables, multiple joins of tables are necessary. This process is time-consuming and a cause for a decrease in performance [DU04].\n\n2.3 The OO Model\n\nIn the OO model (also known as OO programming model), objects are structures which combine related data and code (operations). Each object is considered as an instance of a class. Encapsulation, inheritance and polymorphism are the properties of the OO model. Encapsulation means that code and data are grouped together to construct objects. The construction of each object can be hidden from the rest of the program. This can help developers to manage the program’s structure in a simple way. An inheritance feature allows the class to inherit many of its features from other existing classes. This can make OO program easier to change [Nic07]. Polymorphism refers to operations with the same name but have a slightly different meaning when they are applied to different data. In an OO model, pointers and nesting are used to establish relationships between objects. An OO model is based on the combination of data and code, different data types and also hierarchical relationships within data types and references [DD88].\n\n2.4 The reasons for combining Relational Database Model and OO Model\n\nIt is stated in [PRBV90] that ‘A relational database management system and an OO language can be combined to yield a surprisingly effective OO database system for many applications’. However combining them can cause difficulties. This will be discussed in Section 2.5. Relational database systems and OO programming languages have complementary strengths. The main reason for combining these two systems are, on one hand, OO programming language is used by most of the developers to implement their applications and on the other hand, relational databases are mostly used to store data. The combination of these two systems can manage large amounts of data.\nThe more complex the collection of information and the more levels of hierarchy and cross relationships, the more difficult it is to represent it within a simple table structure of a relational database [Blo03].\n\nIt is difficult to store and manipulate complex data objects like nested objects or unstructured data with the relational database [LKK00] [SKS10]. Compared to OO programming language, they can manage these complex relationships among objects [SKS10]. This can be considered as an advantage of using OO model.\n\nOO programming language, provides almost no support for data persistence and retrieval [Nie89]. In contrast, the relational database system provides more complex persistence of data structures. In other words, in OO programming, files are the only way to make objects persistent while the relational model uses tables and the query languages for persistence on relational tables. But these are not available in OO languages. Moreover, relational database systems can manage large amounts of data [DD88].\n\nThe relational model and the OO model are fundamentally different and combining them can be difficult. On one side there is the OO model and on the database side there is a relational model. It is very expensive to convert the relational system into the OO system. This is discussed in Section 2.5.\n\n2.5 Problem of Combining of the Relational Model and the OO model\n\nIn order to implement an OO database application, objects are constructed at the run time of an application not at implementation time. To achieve this, functions must be written for each class which can retrieve data and store it in the database. Other functions must be written to store objects and to retrieve their data from the database. A separate table must be created for each level in the hierarchy to store hierarchical structures in a relational database [DD88]. This process is very\n2.5. Problem of Combining of the Relational Model and the OO model\n\ntime-consuming and has a negative effect on the performance of the application. Furthermore, relational databases do not support the encapsulation and polymorphism as featured in the OO model. This also has a negative effect on the performance of the application.\n\n2.5.1 Impedance Mismatch\n\nWith the OO programming languages, like Java, data is represented as interconnected graphs of objects. Relational database management systems represent data in a table-like format. When loading and storing linked structures of objects using the relational database, we came across a mismatch problem. This mismatch between the OO model and the relational model is called OR impedance mismatch. In other words, the OO model and the relational model do not have the same data structure [ICK09] [Fin01].\n\nThe definition of impedance mismatch in Wikipedia is described as \"The OR impedance mismatch is a set of conceptual and technical difficulties that are often encountered when a relational database management system (RDBMS) is being used by a program written in an OO programming language or style; particularly when objects or class definitions are mapped in a straightforward way to database tables or relational schema.\"\n\nIn OO model we have objects with various levels of granularity. Granularity refers to the level of hierarchy of objects. In a relational model, granularity is limited to the following levels: Tables, rows, values and columns. The first mismatch between the OO model and the relational model is the result of storing objects with various levels of granularity. These objects are limited in granularity which can cause a mismatch. The second mismatch is an inheritance mismatch which is the result of the mapping of object inheritance. In Java, an object’s features can be inherited from another object while in the relational database there is no support of inheritance. Therefore, the class hierarchy needs to be translated to a database schema. Association mismatch is another type of mismatch between the OO model and the relational model. Associations in OO models is achieved by object references which are directional, whereas, foreign keys are used to associate two entities in the relational model. An\nassociation implemented as a foreign key is not directional. This means that, if an association between objects should be navigable in both directions, the associations must be found twice, once in each of the association classes.\n\nAnother mismatch is data navigation mismatch. In Java we navigate from one object to another object in the object graph. Therefore, to find a particular item we navigate from one object to another, following the associations between the objects until we reach that particular item. So the way that we access data in Java is fundamentally different than in the relational database.\n\nImpedance mismatch commonly occurs when a developer needs access to existing data which is held in a relational database. In this situation OR mapping is one of the useful ways to prevent impedance mismatch.\n\n## 2.6 Solutions for Impedance Mismatch\n\nThere are a number of solutions for impedance mismatch. These include using the OO database system, OR database systems or modifying OR mapping. In this section, each solution is discussed in detail.\n\n### 2.6.1 OO Database Systems\n\nThe first solution is to use the OO database system. It transforms the relational database system to the OO database system. In [Sik03] it is claimed that \"OO database systems evolved from a need to satisfy the demand for a more appropriate representation and modelling of real world entities. So OO databases provide a much richer data model than conventional (relational) databases\". The problem of transforming rows into objects in the relational tables, occurs when developers need to use relational databases instead of OO databases in OO programming language [Kel97].\n\nThe data in an OO database is persistent data and when this data is read by an application, it stores data as transient data. It can also be stored as persistent data as well. As soon as the program finishes, transient data will be lost. Persistent data\ncan be stored and it can be reused for the next execution of the program. Persistent data can be shared, accessed and updated by a database application [KA90]. One of the advantages of the OO database systems is that there is no need for developers to maintain the relationship between persistent objects and transient objects. Another advantage of using the OO database is that the problem of impedance mismatch is solved by using a unified view of data in OO programming language and in the database. The OO database system can also support inheritance [Sta98].\n\nOO databases have some disadvantages. They have limited support for consistency constraints and limited performance-tuning capabilities [Sik03]. Also, the problem of impedance mismatch is eliminated when the relational database is copied into the OO database. However, by using this approach, the relational database is copied into the OO database but transferring data between the relational database and OR database is very time-consuming. Therefore, without considering the performance problem of the application, this approach can solve the impedance mismatch problem.\n\n2.6.2 The OR Database models\n\nThe OR model is a model between the relational model and the OO model. Objects in an OR database model need persistence; a data model; a query language to manipulate, retrieve and store data; and also a database model [Nie89]. In some models, the OR model uses the object view to access relational data. An object view is a way to access relational data using the OR features. It allows developers to develop OO applications without changing the underlying relational schema [Dat08].\n\nAn OR database consists of tables of objects including properties and relationships which can be manipulated by methods, stored procedures or query languages. OR database technology is a hybrid between the relational database models and OO database models. An OR database models, uses OR database management systems (ORDBMS) for data management [Nic07]. Relational databases are unable to store complex data whereas an ORDBMS can deal with large amounts of high complexity data.\nOne of the advantages of using an OR database model rather than the relational database for OO applications is such that it solves the problem of impedance mismatch between the OO application and the relational model [Nic07] [CB01] [ABD+89]. The OR database model is using object tables instead of relational tables to store data in an OO application. This means less programming code is required followed by less development time. Other advantages of OR databases are reusability, maintainability, flexibility and functionality.\n\n2.6.3 OR Mapping\n\nIf a row needs to be stored in or retrieved from a relational database using an OO programming language, an object view of this row in OO language must be provided. The differences between the OO model and the relational model must be overcome [Kel97].\n\nOR mapping allows the conversion of data between inconsistent systems like tables and objects in the OO programming languages. OR mapping is one of the most common data access techniques to cope with the problem of OR impedance mismatch. OR mapping can simplify the development of application by automating the object-to-table and table-to-object exchange. This can make the implementation of application simple.\n\nComplex objects and relationships in the application, causes a higher level of impedance mismatch. The higher level of impedance mismatch leads to the development of additional code to copy objects into relational tables, resulting in slower application development and weak performance of the application [DU04].\n\n2.7 Modern OR Mapping Frameworks\n\nThere are different persistent frameworks and OR Mapping(ORM) frameworks available. In this section, a survey of LINQ, Hibernate and Ruby on Rails is presented. Also, the methods are compared and analysed.\n2.7. Modern OR Mapping Frameworks\n\n2.7.1 LINQ\n\nThe Microsoft Language Integrated Query (LINQ) is an OR mapping framework which helps developers query data. There are five different implementations for LINQ presented by Microsoft. The LINQ to SQL and LINQ to Entities are the ones that need access to relational databases using OR mapping [MEW08]. Both LINQ to SQL and LINQ to Entities ORM frameworks, support the mapping of a Microsoft SQL Server database to .NET classes [MEW08]. It executes the output of the query using LINQ.\n\nBoth of these LINQ implantations, cover OR mapping within Microsoft SQL Server and third party databases. This thesis considers mapping between the Oracle database and the Netbeans classes. Therefore, LINQ is not considered as a framework for OR mapping in this thesis.\n\n2.7.2 Ruby on Rail\n\nRuby on Rails is an open-source web framework which presents different ORM tools. The most popular ORM tools within Ruby on Rails are Datamapper and Sequel [BFP+15].\n\nUsing Activerecord leads to work with models rather than data. It automatically converts data to models. Therefore, all the associations are built and based on the models. The disadvantage of Activerecord is that it increases the complexity of the objects. Therefore the run time increases. A Sequel framework is implemented based on Activerecord. It supports stored procedures and advanced database functions. Datamapper was presented as another ORM framework to complete the Activerecord and make the ORM faster. Datamapper separates the OO model from database logics.\n\nAll the presented ORM tools across Ruby on Rail are able to optimise the ORM process. However, it can also cause performance delay during the execution of the application.\n2.7.3 Hibernate\n\nHibernate is a powerful Java persistent mapping tool for OR applications which enables accessing complex data [OLM14]. It supports mapping from Java classes to database tables and from Java data types to SQL data types. Hibernate focuses on data-processing using JDBC and SQL. It also enables data and tables to be persistent. It uses data persistence from the relational database. Persistence simply keeps some data out of the scope of the application process [BK06]. Hibernate uses a two-layer caching system for performance solutions.\n\nHibernate can be used as a tool which can provide automate mapping [OLM14]. Therefore in future work, hibernate can be considered within the transformation process. This will be discussed further in Chapter 7.\n\n2.7.4 Conclusion\n\nAlthough using ORM framework can speed up the development time of an application, it adds overhead to the application. This means that by using ORM framework memory and CPU usage will increase. Also, using ORM framework for implementing queries with simple functions such as update, delete and comparison are slower than using SQL. For these reasons, ORM frameworks are not considered as an ORM solution within this thesis.\n\n2.8 Previous works\n\nA number of approaches have been proposed in order to improve the efficiency of OR applications. These include performance tuning, transformation methodology, integrating data and refactoring.\n\n2.8.1 Performance Tuning and Transformation Methods\n\nAgarwal proposed the idea of using a client-side object cache in order to increase the performance of the application. It is suggested that the actual performance was greatly dependent on the degree to which the application can take advantage of data stored in the object cache. The problem of this method, however, is that special\ncare must be given to the complexity of the query so that it can return instances of commonly used classes with minimum use of joins [Aga95].\n\nIn 2006, research focused on comparing the performance of object databases and OR mapping tools. This research discussed OR mapping in open source applications [vZKB06]. This approach, however, only dealt with one framework. Moreover it was not applied on the distributed (client-server) or multi-user systems which are often used by developers.\n\nKalantari et al. compared the performance of the object and OR database models. Certain factors were suggested in this research and system developers need to consider them when selecting a database management system for persisting objects [KB10]. This research is based on basic query implementation which means that it did not consider complex queries.\n\nRahayu et al. discussed the performance evaluation of OR transformation methodology. The aim of this research was to clarify the efficiency of the operations on relational tables based on certain OR transformation methodology [RWD01]. The performance of OR transformation methodology was also compared with that of the conventional relational model. This research, however, did not compare the existing relational database design methodology and their OR transformation methodology.\n\nMeng et al. proposed the transformation rules for the OO database systems. The rules used in this research were designed to transform the structural part of a OO database schema to an equivalent relational schema [MYK+93]. These rules provided a relational view of the OO database schema for relational users. The research is limited to the structure of a relational front end for OO database systems.\n\nThe idea of translating queries from an SQL into an OQL in an automatic way, were suggested by Mostefaoui et al. This method was based on graph representations [MK98]. A formal approach to translation of OO database queries into equivalent relational queries was proposed by Yu et al who used the same method as Mostefaoui et al. in [MK98] [YZM+95]. These works, however, did not consider all the possible forms of SQL queries. In addition, the methods suggested were not general enough to be extended to other clauses and they could not address the performance problem\n2.8. Previous works\n\nGrust et al (2009), developed the FERRY language designed as an intermediate language. The FERRY language permits developers to access database tables using their programming language’s own syntax and idiom [TMJT09]. In 2010 the same authors extended this approach by proposing the FERRY-based LINQ to SQL approach [SBG+10]. Both proposals were based on compiling the first-order functional programs into SQL which is not an applicable approach in industry.\n\nRecently, Chen et al. proposed a framework which can detect and prioritise instances of OR mapping performance anti-patterns [CSJ+14] and therefore improve the system’s response time. This is a useful framework but this approach can only detect performance bugs and leaves the debugging process for the developer.\n\n2.8.2 Integrating Data and Refactoring\n\nIn 2001, a pragmatic approach to schema integration was proposed by Lawrence et al. In this approach, the query processor translates semantic queries into structural expressions [LB01]. This approach needs to be standardised in order to be performed automatically.\n\nThe approach of processing the integration of complex databases using the IIS*Case was proposed in 2006 by Ivan et al. The functionality of IIS*Case needs to be extended, however, in order to be able to support the complete development of an information system [LRMP06]. In this research, the performance problem of distributed information systems was not considered as a challenge in integrating the data models.\n\nIn 2010, the idea of refactoring SQL was presented by Jacobs et al. Their method relied on finding common anti-patterns and techniques [Jac14]. The proposed method was not extensible, however, and not general enough to cover most common queries.\n\nAnother research on refactoring was done in 2006 by Michael et al. This approach [MGB10] covers the ability to reduce code volume and the number of modules and\nfiles needed during maintenance [MGB10]. The main problem with this approach, is a reduction in performance of the application. This approach is also unable to manage the refactoring of the application automatically.\n\nZibran et al. proposed a model for refactoring code clones in the OO source code [ZR11b]. This model is useful for estimating the efforts required for code clone refactoring [ZR11a] but it is not applicable for industrial software systems written in other programming languages. Also, a refactoring tool suggested by Zibran et al. was the clone detection part of a refactoring system [ZR11b]. This research did not consider the performance of the output application in the implementation of their refactoring system.\n\nIn 2009, Liu et al analysed the relationships among different approaches to software refactoring [LYN+09]. In this research, however there is no support for resolution orders of software refactoring either for software development.\n\n## 2.9 Conclusions\n\nThere have been many attempts to combine relational and OO concepts in order to improve performance of the applications. It has been done primarily by designing rules for the transformation from an OO model into a relational model or vice-versa. Other methods of refactoring were proposed by only a few.\n\nMost of the current transformation methodologies are based on using first-order functional programming languages and this is not applicable in industry. Most of the current refactoring methods have a negative impact on the performance of the application.\n\nMultiple unnecessary iterations are a main remaining problem in all of the current approaches. This means that an approach is required which can eliminate these iterations in order to achieve better efficiency.\nChapter 3\n\nTransformation Rules\n\n3.1 Introduction\n\nThe transformation rules optimise non-optimised versions of the OR database applications to provide the necessary efficiency. The rules replace fragments of procedural code with non-procedural statements of OQL which leave most of the data processing on the server side. The transformation rules consist of two components: input and output components. The input component is a code based on a non-optimised version of the application written by the OO programmer. The rules are applied to the input component and as a result the output is achieved. The output component is a code based on the optimised version of the application after applying the rules. The output component is achieved by using more non-procedural code and changing the structure of the input component.\n\nThis thesis assumes that OR applications consist of three categories as follows:\n\n1. Filtering\n\n2. Traversal of Association\n - Join Traversal\n - Anti-Join Traversal\n\n3. Aggregation\n\nThe filtering category refers to applications which filter objects using specific conditions. The view of the OO programmer about OR database is classes of objects with associations and properties. From a programmer’s point of view, the data manipulation on relational tables are hidden behind the operations on the classes and\nassociations. Therefore, to obtain information from more than one class, navigating through associations from one class to another class is required. This forces the application to use mapping. Both Join Traversal and Anti-Join Traversal categories, refer to navigation through associations of two classes. Anti-Join Traversal category is supposed to find objects from one class which are not related to the objects in the other class. For both join traversal and anti-join traversal, navigating through associations is required. The last category refers to the applications with aggregation functions.\n\nFor the rest of this chapter, relational conditions referred to as the conditions which are discussed are needed to navigate through the associations of two classes of objects. The non-relational conditions are the conditions of one class without having any relation to the other classes.\n\nLarge OR applications are a combination of different applications from the proposed categories (filtering, traversal of association and aggregation). Therefore, the rules can convert most of the applications from the non-optimised versions to an optimised one. An explanation as to how to apply the rules to the combination of the proposed categories (filtering, traversal of association and aggregation) is offered in Chapter 4.\n\nThe transformation rules support most standard SQL/OQL functions within OR applications. It can supports functions that return value such as boolean expression (AND, OR) and comparison functions.\n\n### 3.2 Filtering Rule\n\n#### 3.2.1 Input Component\n\nEvery OR application may include an iteration over one class of objects. These applications have some filtering conditions used to select some desired objects for output. The input and output components are presented as a pair of algorithms. By using the transformation rule for the applications in the filtering category, the structure of the application is changed from a program with one SELECT statement\nof object query language (OQL) and one \\textit{IF} clause (as shown in Algorithm 1), to a program with one \\textit{SELECT} statement and one \\textit{WHERE} clause (as shown in Algorithm 2). In Algorithm 1, \\( t \\) is considered as an object variable. Algorithm 1, is the input component for this rule while Algorithm 2, is the output component after applying the above changes to the input component. Also, the \"\\textit{Processing} \\( (t) \\)\" is considered as a block of code that can processes an object \\( t \\). The application developer can write the \"\\textit{Processing} \\( (t) \\)\" section differently depending on the aim of the application.\n\nAssume that \\( \\varphi [t.t_1,t.t_2,...,t.t_n] \\) is a filtering condition. \\( \\varphi \\) is a Boolean expression. An example of \\( \\varphi [t.t_1,t.t_2,...,t.t_n] \\) is: Class1. Member\\( \\alpha \\) Value. \\( \\alpha \\) is an operation such as <, >, =, ! =. \\( t_1,t_2,...,t_n \\) all are the properties of Class1. \"Value\" is any number or string. The operation between the conditions can be \\textit{And}, \\textit{Or} or \\textit{Not}. The condition is based on the object \\( t \\). Each filtering condition is applied by making reference to the object variable.\n\nFor instance: \\( t.\\text{Department\\_name} = \\text{“finance”} \\). In this example, \"\\( t \\)\" is an object from Class1 and \"\\text{Department\\_name}\" is a property of Class1. The \"\\( \\alpha \\)\" in this example is \"\\( = \\)\" and \"Value\" is a string: \"finance\".\n\n\\begin{algorithm}\n\\begin{algorithmic}[1]\n\\State \\textbf{for} each \\( t \\) in (\\textit{SELECT} * FROM Class) \\textbf{do}\n\\State \\textbf{if} \\( \\varphi [t.t_1,t.t_2,...,t.t_n] \\) \\textbf{then}\n\\State \\hspace{1em} \\textbf{Processing} \\( (t) \\)\n\\end{algorithmic}\n\\end{algorithm}\n\nIn Algorithm 1, all of the objects from the \\textit{Class} are selected and then the filtering conditions are applied to the objects. This way of implementing the filtering part of the application leads to an iteration over all objects in \\textit{Class}. \\( \\varphi [t.t_1,t.t_2,...,t.t_n] \\) shows different filtering conditions for different objects in the class. This means that each object can be filtered by a condition and those conditions can be different to each other.\n\nEvaluation of each condition requires transmission of all objects from the database over the network. Conditions are computed on the client side which leads to having\ninefficient applications due to the transmission of a large number of objects. As an example of the input component of this rule, a pseudo-code with OQL statements is presented in Algorithm 2.\n\n### Algorithm 2: Example 1/Non-Optimised version\n\n1. for each t in (SELECT * FROM Department) do\n2. if t.Department_id = 123 ∧ t.Department_name = \"finance\" then\n3. Write t\n\n### 3.2.2 Output Component\n\nAlgorithm 3 is the output component of the filtering rule. Condition in the input component $\\varphi [t_1, t_2, ..., t_n]$ is converted to a OQL condition $\\varphi [t_1, t_2, ..., t_n]$ in the output component. In this regard, the references to t has to be removed and the output component includes only the name of the properties. The following algorithm is considered as an output component for filtering applications and has the same output as Algorithm 1. In Algorithm 3, it is assumed that $\\varphi [t_1, t_2, ..., t_n]$ is OQL filtering condition which filters the output.\n\n### Algorithm 3: Output component\n\nFiltering\n\n1. for each t in (SELECT * FROM Class WHERE $\\varphi [t_1, t_2, ..., t_n]$) do\n2. Processing(t)\n\nThe filtering rule can improve the performance of the filtering applications by reducing the transmission of all objects over the network. This rule helps to shift the computation of the conditions to the database (server) side. Therefore, the data-processing is faster because the database server is able to use indexing which can eliminate iterating over all the objects.\n\nAlgorithm 4 is as an example of the output component of the filtering rule.\n3.3 Traversal of Association\n\n3.3.1 Join Traversal\n\nInput Component\n\nIn this section the input component of the join traversal is presented. The input component which is presented as Algorithm 5, is based on nested loops. The nested loops implementation of join, takes an object variable from the outer loop. The property value of this object will pass to the condition of the other loop as the object on the other side of the association. Algorithm 5 includes two nested SELECT statements which perform the join traversal of associations. This traversal of the association is implemented either as nested loops or as an OQL’s join.\n\nThe two SELECT statements in this algorithm compute the JOIN operation. Non-relational conditions are the conditions belonging to only one class without having relation to the other class. Non-relational conditions for Class 1 are presented in the outer SELECT statement as \\( \\varphi [t_1, ..., t_n] \\). The inner class, Class 2, includes both the non-relational and relational conditions. The non-relational conditions of Class 2 are presented by \\( \\gamma [s_1, s_2, ..., s_n] \\). The internal structure of this condition is such that it includes different non-relational conditions for different members of Class 2. The operation between the conditions can be And, Or or Not which is different depending on different application. The relational conditions between Class 1 and Class 2 are denoted as \\( \\gamma' [<s.s_1, t.t_1>, ..., <s.s_n, t.t_n>] \\). In this condition,\n\n---\n\n**Algorithm 4**: Example 1/Optimise version\n\n1. for each \\( k \\) in (SELECT * FROM Department WHERE\n Department.Department_id = 123 \\&\\& Department.name = \"finance\") do\n2. Write \\( k \\)\n\nBoth algorithm 2 and algorithm 4, return objects from the Department class which satisfy the filtering condition. Department_id = 123. ‘k’ is an object variable which contains the output.\n3.3. Traversal of Association\n\nt and s are object variables which return the objects to satisfy the conditions in Class 1 and Class 2. For instance, $\\gamma' [<s.s_1, t.t_1>]$ includes a part from class1, t.t1, and a part from Class 2, s.s1. Therefore there is relation between these two parts and the objects which satisfy the condition between these two parts would be the output. An example of $\\varphi [t]: \\varphi [t_1, ..., t_n]$ is Class1.Member$_i$=Value. An example of $\\gamma [s]: \\gamma [s_1, s_2, ..., s_n]$ is Class2.Member$_j$=Value. Value can be any type i.e. of number or string. An example of the function: $\\gamma' [<s.s_1, t.t_1>, ..., <s.s_n, t.t_n>]$ is Class2.Member$_j$ = Class1.Member$_i$.\n\nThe computation of the above algorithm describes in the WHERE clause of the inner SELECT statement, before concatenation, there is a non-relational statement, $\\gamma [s_1, s_2, ..., s_n]$, which is and-ed with relational conditions. The relational conditions includes properties of both classes which are appended to OQL string. This string uses references to variable t as follow: $\\gamma' [<s.s_1, t.t_1>, ..., <s.s_n, t.t_n>]$. t is the object variable used for the first class and s is used for second class.\n\nAssume that $\\land$ means AND. In Algorithm 5, $\\land$ is is used between non-relational conditions and relational conditions of the inner loop.\n\nAlgorithm 5: Input component\n\n<table>\n<thead>\n<tr>\n<th>Algorithm 5: Input component</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Iterations over two classes of objects</td>\n</tr>\n<tr>\n<td>1 for each t in (SELECT * FROM Class1 WHERE $\\varphi [t_1, ..., t_n]$) do</td>\n</tr>\n<tr>\n<td>2 for each s in (SELECT * FROM Class2 WHERE $\\gamma [s_1, s_2, ..., s_n] \\land \\gamma' [<s.s_1, t.t_1>, ..., <s.s_n, t.t_n>]$) do</td>\n</tr>\n<tr>\n<td>3 Processing(t,s)</td>\n</tr>\n</tbody>\n</table>\n\nAlgorithm 6 is presented as pseudo-code with OQL statements as an example of the input component of this rule. Variables t and s are considered as object variables from the Department and the Employee respectively. The Department and Employee classes are mapped to the Department table and Employee table respectively. The variable p is a set which includes the result of t and s: p $<t,s>$. p $<t,s>$, and includes both t and s.\n3.3. Traversal of Association\n\nAlgorithm 6: Example 2/Non-Optimise version\n\n\\begin{algorithm}\n\\begin{algorithmic}\n\\State \\textbf{for} each \\( t \\) in (SELECT * FROM Department) \\textbf{do}\n\\State \\hspace{1em} \\textbf{for} each \\( s \\) in (SELECT * FROM Employee WHERE \\( t.Department\\_id = s.\\ Department\\_id \\)) \\textbf{do}\n\\State \\hspace{2em} Write \\( p <t,s> \\)\n\\end{algorithmic}\n\\end{algorithm}\n\nOutput Component\n\nThe output component implements join in OQL. To write the output component of this rule, more non-procedural code is used than procedural. Two SELECT statements in the input component are merged into one SELECT statement with a Join clause to create the output component. Non-relational conditions have the same format as the input component. The relational conditions in the output component do not have references to the objects. In the output component, AND or propositional conjunction are used to merge the non-relational conditions of both classes. By using this rule, filtering conditions are applied to the objects on the server side and as a result, only the objects which satisfy the JOIN condition will transfer to the client side. Therefore, unnecessary data is not transmitted.\n\nAssume that \\( \\gamma' [<t_1,s_1>,<t_1,s_2>,...,<t_n,s_n>] \\) is a join condition. The entire OQL statement are transformed into a statement in SQL on the database side at the output component. The transformed statement is a join statement. Therefore, for each \\( <t_i,s_j>, \\gamma' [<t_i,s_j>] \\) is the join condition between the member\\(_i\\) of class\\(_1\\) and the member\\(_j\\) of class\\(_2\\).\n\nAlgorithm 7: Output component\n\nJoin two classes of objects\n\n\\begin{algorithm}\n\\begin{algorithmic}\n\\State \\textbf{for} each \\( p \\) in (SELECT * FROM Class1 \\textbf{Join} Class2 on \\( \\gamma' [<t_1,s_1>,<t_1,s_2>,...,<t_n,s_n>] \\)) \\textbf{where} \\( \\varphi [t_1,\\ldots,t_n] \\land \\gamma [s_1,s_2,\\ldots,s_n] \\) \\textbf{do}\n\\State \\hspace{1em} Processing\\( (p) \\)\n\\end{algorithmic}\n\\end{algorithm}\n\nBy using this rule, implementation of the traversal of the associations is converted\nfrom two nested loops into a join in OQL. This is implemented by having relational conditions of two classes as a join condition. The other non-relational conditions remain as WHERE clause conditions. The relational conditions are used as join conditions, so the references to the object variables \\( t \\) and \\( s \\) which are used in the input component are eliminated.\n\nMost of the data processing is shifted to the server side by using this rule. This will decrease the unnecessary transmission of data from the server side. Also, the output component is implemented in a way that allows the database system to use a join algorithm. It will be more efficient than the nested loops implementation in the input component. This leads to achieving a better performance of the application.\n\n**Algorithm 8: Example 2/Optimised version**\n\n1. for each \\( p \\) in (SELECT * FROM Department join Employee on Department.Department_id = Employee. Department_id) do\n2. Write \\( p \\)\n\nAlgorithm 8 is presented as an example of the output component of this rule. The query optimiser is allowed to find better implementation of join to retrieve data, by using join in this version of the program. Both optimise and non-optimise versions of the application results in the same output. All the objects from the Department and Employee classes which have the same Department_id are selected as the output in the presented application in Algorithm 6 and 8. Also all the object which satisfy the condition in the WHERE clause are added to the output.\n\n### 3.3.2 Anti-Join Traversal\n\n**Input Component 1**\n\nAnti-join applications, retrieve the objects from one class where there is no related object in the other class. One of the frequently used implementations of anti-join is introduced as Algorithm 9. The input component, includes two SELECT statements. The first SELECT statement doesn’t include any conditions and obtains object from \\( \\text{Class 1} \\) in object variable \\( t \\). The inner SELECT statements includes anti-join conditions. Before entering the second loop, there is a variable initialised to \\( \\text{False} \\).\nThis variable will become true if the SELECT statement finds any object from Class 2 which satisfies the anti-join condition. The object variable is \\( t \\) an object variable from Class 1.\n\nThere are a number of different ways to implement anti-join applications. This thesis considers anti-join applications which can be implemented with not-exist. Note that any not found statement can be re-written into an equivalent not-exist statement. For example, if it is not-found then EXIT the loop is equivalent to if it is not-exist then EXIT the loop.\n\nAlgorithm 9: Input component 1\n\nAnti-Join by Variable\n\n1 for each \\( t \\) in (SELECT * FROM Class 1) do\n2 Found = False\n3 for each \\( s \\) in (SELECT * FROM Class 2) do\n4 \\( \\text{if } \\gamma'[[s.s_1, t.t_1], ..., [s.s_n, t.t_n]] \\text{ then} \\)\n5 \\( \\text{Found} = \\text{True} \\)\n6 \\( \\text{Exit the loop} \\)\n7 if not Found then\n8 \\( \\text{Processing}(t) \\)\n\nAlgorithm 10 is presented, to show the input component of this rule.\n\nAlgorithm 10: Example 3/Non-Optimise version\n\n1 for each \\( t \\) in (SELECT * FROM Department) do\n2 Found = False\n3 for each \\( s \\) in (SELECT * FROM Employee) do\n4 \\( \\text{if } t.\\text{Department}_id = s. \\text{Department}_id \\text{ then} \\)\n5 \\( \\text{Found} = \\text{True} \\)\n6 \\( \\text{Exit the loop} \\)\n7 if not Found then\n8 \\( \\text{Write}(t) \\)\nThe output of Algorithm 10 is all of the department-id from the Department class which are not related to any department-id in the Employee class. In other words, the application will find all the department-id from the Department class which are not the same as the department-id in Employee class. This is an example of anti-join application.\n\n### Output Component\n\nThe output component for anti-join is implemented by one SELECT statement using our approach. The left-outer-join is used in the output component of this rule to select the objects which satisfies the anti-join conditions and makes it unnecessary to transfer them to the client side. The following algorithm can be used as an output component for two different implementations of the anti-join’s input components.\n\nThe left outer join condition consists of the object variables $t$ and $s$ which are the object variables from Class1 and Class2 respectively.\n\n#### Algorithm 11: Output component\n\n**Anti-Join by Left outer join**\n\n1. for each $p$ in (SELECT * FROM Class1 Left Outer Join Class2 on $\\gamma' [<t_1, s_1>, <t_1, s_2>, ..., <t_n, s_n>]$) do\n2. if $p$ is Null then\n3. Processing($p$)\n\nImplementing the anti-join algorithm is based on the input component structure by the nested loop join as a possible case. However, for large databases it is not efficient to use this structure because navigating through associations by nested loops, is based on comparing each object with an entire class. The output component executes faster than the input component. The output component operates on object variable $p$. The following algorithm is an example of the output component of this rule.\nAlgorithm 12: Example 3/Optimised version\n\n1 for each p in (SELECT * FROM Department left outer join Employee on Department.Department_id = Employee.Department_id) WHERE p.Employee.Department_id is Null do\n2 Write p\n\nInput Component 2\n\nThere are different ways to implement anti-join applications. However, there are two common implementations mostly presented by the application developers. The first style of anti-join application is described in Section 3.3.2. The second common possible input component for the anti-join is presented here. The application programmer can design an anti-join algorithm by using a counter in the body of the application. In this case, there are two SELECT statements. Inside the first SELECT statement there is not any condition and the objects from this class will pass to the object variable t. The inner SELECT statement includes the anti-join condition and the counter. The counter is checked to find the object from the first class which is the same in the other class. In this case the counter would not be zero at the end of the loop, so the objects which are not the same, are the output.\n\nThe output of Algorithm 13 is the same as the output for Algorithm 9 which is Algorithm 11.\n\nThe variable $s_i$ is a member of Class2. $i$ is a positive number so the variable $s_i$ is one of the objects from Class2. An example of Class2.$s_1,t_1$: Employee.employee_id= t.employee_id.\n3.4. Aggregation\n\nAlgorithm 13: Input component 2\nAnti-Join by Counter\n\n1. Count=0\n2. for each t in (SELECT * FROM Class1) do\n3. Count= (SELECT Count(*) FROM Class2\n4. WHERE\n5. γ' [Class2.s1, t.t1 >, ..., Class2.sn, t.tn >])\n6. if Count=0 then\n7. Processing(t)\n\nThe problem of different implementations of the input component is already solved by software patterns which will be presented in Chapter 4.\n\n3.4 Aggregation\n\nFor aggregation applications, one input and one output components is proposed. These input and output component are applicable to different aggregation functions such as Min, Max, Average and Count.\n\n3.4.1 Input Component\n\nThe most common implementation of aggregation queries is modelled in Algorithm 14. Algorithm 14 is an input component of aggregation applications. In this implementation of aggregation applications, developers are using nested SELECT statements to find the appropriate objects for aggregation function from a class. Two nested SELECT statements are presented by OO programmers to build the aggregation functions, but this is not suitable for the implementation of OO applications. This nested loops implementation, takes an object variable from the outer loop and the value of the property of this object is transferred to the condition of the other loop. In this structure, an alias for the class is used to run the aggregation function for representative objects from Class. The aggregation rule is based on finding desired objects in a class and then applying the aggregation function to them. F(x) is a COUNT(*) in the input component and COUNT(Memberi) in the output component, for counting similar objects from a class of objects. This structure for aggregation\n3.4. Aggregation\n\nqueries transfers all the objects from the server side to the client. Then the Class is considered as a group of objects.\n\nIn line 2, the RESULT is a variable which stores results of second loop. It is assumed that F(x) is an aggregation function such as Min, Max, Average and Count. In this function object variable s is used. It is assumed that WHERE condition is a condition between members of Class1 and Class2. For instance it can be Class1.Member_i = Class2.Member_i.\n\nAlgorithm 14 is an input component of aggregation queries.\n\nAlgorithm 14: Input component\n\nAggregation with nested loop\n\n1 for each t in (SELECT Member_i FROM Class 1) do\n2 for each s in (SELECT F(x) FROM Class 2 as RESULT\n3 WHERE\n4 t.Member_i = Class 2.Member_j) do\n5 Processing <t, s>\n\nAn example of the input component of this rule is presented as Algorithm 15.\n\nAlgorithm 15: Example 4/Non-Optimised version\n\n1 for each t in (SELECT * FROM Department) do\n2 for each s in (SELECT count(*) as TOTAL FROM Employee\n3 WHERE\n4 t.Deptartment_id = Employee. Department_id) do\n5 Write <t, s>\n\nAlgorithm 15 consists of two nested loops. The outer loop selects all objects from\n3.4. Aggregation\n\nclass Department and passes the result to the second loop. The inner select statement is responsible to find all the objects which satisfy the condition (t.Department.id = Employee. Department.id). The output of this algorithm is the result of the count function which counts the number of the same department-id from both the Department and Employee.\n\n3.4.2 Output Component\n\nThe Group by clause is used to group the necessary objects and transfer them to the client side, in the output component of this rule. Therefore, compared to the input component, less objects will be transferred from the server side. F(x) can be replaced by any of the aggregation functions. For instance, Count(*) can be used instead of F(x) in the output component to count objects.\n\nAlgorithm 16: Output component\n\nCounting and grouping objects\n\nfor each p in (SELECT Member_i, F(x) as RESULT FROM Class 1, Class 2 WHERE γ’ [<s_1,t_1>,...,<s_n,t_n>]) Group by Member_i FROM Class 1 do\n\nAlgorithm 16 minimises the run-time of an aggregation application. The reason is using of Group by clause in the output component. The Group by clause is used to divide the objects into groups. In the input component without Group by, the entire class is considered as one group. An example of the output component is presented in Algorithm 17.\n\nAlgorithm 17: Example 4/Optimised version\n\nfor each p in (SELECT count(Department.Department_id) as TOTAL FROM Department, Employee WHERE Department.Department_id = Employee. Department_id GROUP BY Department.Department_id) do\n\nWrite (p)\n3.4. Aggregation\n\nAll of the objects with the same department \\textit{id} from both the \\textit{Department} and the \\textit{Employee} classes are selected. The output of this application is the result of counting.\nChapter 4\n\nCorrectness of Transformation Rules\n\n4.1 Introduction\n\nThe Hoare rules or the FloydHoare logic is a formal method to prove the correctness of computer programs. This method is based on logical rules and it has been used by computer scientists and logicians since 1969 [AA78].\n\nThe Floyd Hoare logic is used to prove the correctness of each rule. Also this method shows that in each rule both input and output components achieve the same output. Writing the same invariant for the input and output component of each rule allows us to prove the correctness of each rule. The algorithms under analysis have been rewritten using While in order to be consistent with the Floyd Hoare logic format which is presented in [AA78]. Based on the definition of the Floyd Hoare logic, the invariant of each algorithm must represent the structure of the algorithm. For instance, the invariant for join algorithm must represent the join operation based on the structure of that rule. An invariant is invented for both input and output components of each rule. This invariant must be true before and after the while loop. This means that before and after entering the While loop, the structure of the algorithm is the same. Therefore, the whole algorithm is correct. If the input and output components have the same invariant, then the both algorithm representing the same operation. The correctness of each individual algorithm is proved by writing an invariant for each algorithm. The equality of both components is proved by verifying the same invariant for each pair of the rules.\n\nIn this section, first the Floyd Hoare logic is explained briefly, then the proof for the first group of the applications (iterating over a class of objects) along with the method of verification of the rule is described. In the following algorithm, everything\ninside the curly brackets is related to loop invariants and pre-condition of the Floyd Hoare logic and must not be considered as a part of the algorithm.\n\nFloyd Hoare logic or Hoare rule is as follow:\n\n\\[ \\{ P \\land B \\} S \\{ P \\} \\]\n\\[ \\{ P \\} \\text{while}(B)\\text{do}(S)\\{ \\neg B \\land P \\} \\]\n\nWhere P is the loop invariant which should to be preserved by the loop body S. B is the condition of the application. After the loop is finished, this invariant P still holds, and moreover \\( \\neg B \\) must have caused the loop to end. Loop invariants are used to prove the correctness of the loop properties. Assertions on state enters the loop and guarantees to be true at every iteration of the loop. The invariant is the post-condition for the loop on exit. The logic includes two separate parts (some logics are placed over the line and some others underline). The correctness of the under the line logics is automatically proven by proving the correctness of the over the line logics. As a result all of the functions are correct. Hoare logic is complete, so it is a reliable method for proving the algorithms.\n\n\\[ \\{ \\text{Loop Invariant} \\land \\text{Condition} \\} \\text{Body} \\{ \\text{Loop Invariant} \\} \\]\n\\[ \\{ \\text{Loop Invariant} \\} \\text{while}(\\text{Condition}) \\text{ do } (\\text{Body}) \\{ \\neg \\text{Condition} \\land \\text{LoopInvariant} \\} \\]\n\nThe Hoare logic is applied to all of the proposed algorithms as follow:\n\n4.2 Iteration over one class of object\n\nAlgorithm 18, is an input component of the first rule which has been rewritten with *pseudo-code* using *while* and includes the invariant. The correctness of this input and its output component is described to show the method of proving the other rules. In line 2, all \\( t \\) objects are selected from C. In line 3, before entering the *while* loop, there is a condition and an invariant that are true at that stage of the algorithm. The condition \\( 't <> \\text{Nil}' \\) proves if there is at least one object in class 1 before entering the *while* loop or not. This condition is true before entering the *while* loop. If the\ncondition becomes false then there is no object in \\( \\text{Class} \\), and the loop will be skipped. The invariant before and after the \\( \\text{while} \\) loop is the same: \\( \\forall t \\in R : \\varphi [t] \\). This means only objects that satisfy the condition of \\( \\varphi [t] \\) will go into the output. This invariant is true before entering the \\( \\text{while} \\) loop and also after exiting or skipping the \\( \\text{while} \\) loop. The object which satisfies condition \\( \\varphi [t] \\), will be added to the result set \\( R \\).\n\n- It is assumed that \\( R \\) is the result set\n- It is assumed that \\( C \\) is \\( \\text{SELECT * FROM class 1} \\)\n- It is assumed that \\( t \\) is a set of objects from class 1\n- It is assumed that \\( \\varphi [t.t1, t.t2, ..., t.tn] = \\varphi [t] \\)\n\n**Algorithm 18**: Input component\n\nIterating over a class of object\n\n\\[\n\\begin{align*}\n1 & \\quad \\text{R} := \\emptyset \\\\\n2 & \\quad \\text{Get} \\ (t, C) \\\\\n3 & \\quad \\{(t <> \\text{Nil}) \\land \\forall t \\in R : \\varphi [t]\\} \\\\\n4 & \\quad \\textbf{while} \\ t <> \\text{Nil} \\ \\textbf{do} \\\\\n5 & \\quad \\quad \\textbf{if} \\ \\varphi [t] \\ \\textbf{then} \\\\\n6 & \\quad \\quad \\quad \\text{R} := \\text{R} \\cup [t] \\\\\n7 & \\quad \\quad \\quad \\text{Get} \\ (t, C) \\\\\n8 & \\quad \\{(\\forall t \\in R : \\varphi [t]\\}\n\\end{align*}\n\\]\n\nBased on the Floyd Hoare logic, the logic which is placed above the line for the input component is as follows:\n\n\\[\n\\{\\text{Condition}\\} \\land \\{\\text{Invariant}\\} \\ [\\text{Body}] \\ \\{\\text{Invariant}\\}\n\\]\n\n\\[\n\\{(t <> \\text{Nil}) \\land \\forall t \\in R : \\varphi [t]\\} [\\text{If } \\varphi [t] \\ \\text{Then } \\text{R} := \\text{R} \\cup [t] \\ , \\ \\text{Get} \\ (t, C)]\n\\]\n\n\\[\n\\{(\\forall t \\in R : \\varphi [t]\\}\n\\]\n\nThis is always true as explained in Section 4.1. Therefore the second part is automatically true:\n4.2. Iteration over one class of object\n\n\\{Invariant\\} while(Condition) body \\{¬Condition \\land Invariant\\}\n\n\\{\\forall t \\in R : \\varphi [t]\\} while (t <> Nil) [If \\varphi [t] Then R := R \\cup [t] , Get (t, C)]\n\\{ (t : Nil) \\land \\forall t \\in R : \\varphi [t] \\}\n\nThe correctness of the input component is proved because the same invariant is achieved after finishing the loop. The next stage is to prove that the output is correct by applying the Floyd Hoare logic to the output. Also, the same invariant from both patterns and their outputs is achieved to make the assumption that each pattern and its rule are doing the same thing. Algorithm 19 is the output component for iterating over a class of object, which has been rewritten with a While loop.\n\nIt is assumed that C’ is SELECT * FROM class 1 WHERE \\varphi [t1, t2, ..., tn]\n\nAlgorithm 19: Output component\nRule for iteration over a class of object\n\n1. R := 0\n2. Get (t, C’)\n3. \\{(t <> Nil) \\land \\forall t \\in C' : \\varphi [t] \\land \\forall t \\in R : \\varphi [t]\\}\n4. while t <> Nil do\n 5. R := R \\cup t\n 6. Get (t, C’)\n7. \\{\\forall t \\in R : \\varphi [t]\\}\n\nThe Floyd Hoare logic is applied to the output component as follow.\n\n\\{Condition\\} \\land \\{Invariant\\} [Body] \\{Invariant\\}\n\n\\{(t <> Nil) \\land \\forall t \\in C' : \\varphi [t] \\land \\forall t \\in R : \\varphi [t]\\} [R := R \\cup t, Get(t, C’)]\n\\{\\forall t \\in C' : \\varphi [t] \\land \\forall t \\in R : \\varphi [t]\\}\n\nThis is always true as explained in Section 4.1. Based on the Floyd Hoare Logic, the second part is automatically true because:\n4.3. Traversal of association\n\n\\{\text{Invariant}\\} \\text{while(Condition)body}\\{\\neg \\text{Condition} \\land \\text{Invariant}\\}\n\n\\{\\forall t \\in C' : \\varphi [t] \\land \\forall t \\in R : \\varphi [t] \\} \\text{ while ((t <> Nil) } \\land \\forall t \\in C' : \\varphi [t]) \\ [R := R \\cup t, \\text{Get}(t, C')] \\ {\\forall t : \\text{Nil} \\land \\forall t \\in C' : \\varphi [t]}\\}\n\nThis is always true. Before entering the while loop, both condition and the invariant are true because there must be at least one object to enter the while loop. Each object \\( t \\) can satisfy the condition of \\( \\varphi [t] \\). After exiting or skipping the loop, all the objects in set \\( R \\) satisfy the condition of \\( \\varphi [t] \\). Therefore, based on the Floyd Hoare logic, this rule is proved. In addition, both the input and output components of the rule include the same invariant, so this can prove the equivalence of both algorithms. The same method is used to show the correctness of the other patterns. The term \\( \\forall t \\in R : \\varphi [t] \\) is the invariant for both the input and the output component of the first rule. Therefore, both algorithms perform the same operation and will achieve the same output.\n\n4.3 Traversal of association\n\n4.3.1 Join Traversal\n\nThe same method is used to prove the correctness of the other rules. The input and the output components of the join traversal has been rewritten by a while loop to be matched with the Floyd Hoare logic. The invariant introduced, is based on the body of the code. Algorithm 20 is based on the input component for iteration over two classes of objects.\n\nIn the first line of Algorithm 20, \\( R \\) is the result set which is empty. In line 2 all the objects from Class1 and Class2 are selected. The variable \\( t \\) is a set of objects from class1 and \\( s \\) is a set of objects from Class2. Line 3 presents the invariant of this algorithm. This invariant declares that, for all objects \\( r \\) in the result set \\( R \\) the following statement is correct:\n\nEach object \\( t \\) in Class1 which satisfies the condition \\( \\varphi [t] \\) concatenate with each object \\( s \\) in Class2 which satisfies condition ( \\( \\gamma [s] + \\gamma [t] \\)). + does the AND\noperation. So that the objects which satisfy the join condition from \\textit{Class1} \\ Class2, concatenates together and are added to the result set \\(R\\). Lines 4 to 10 are the \\textit{while} loop.\n\nThis loop presents the input component of the join traversal which is already explained in Section 3.3.1. Before entering the \\textit{while} loop, the invariant is correct. After entering or skipping the loop, the invariant which is presented in line 11 is still correct. This is because the algorithm only accepts the objects that satisfy the \\textit{join} condition.\n\nThe definition of the following assumptions has already been given in 3.3.1.\n\nIt is assumed that \\(r= t \\land s\\)\nIt is assumed that \\(C1(\\text{Class1})\\) is \\texttt{SELECT * FROM Class1 WHERE } \\varphi [t]\nIt is assumed that \\(C2(\\text{Class2})\\) is \\texttt{SELECT * FROM Class2 WHERE } \\gamma [s] \\text{ AND } \\gamma' [s]\n\nAlgorithm 20: \\textit{Input component}\n\n\\begin{verbatim}\nIterating over two classes of object\n\n1 R:= \\emptyset\n2 Get \\((t, C1)\\) , Get \\((s, C2)\\)\n3 \\{\\((t <> \\text{Nil})\\) \\land \\forall r \\in R : \\exists t \\in C1 \\varphi [t] \\land \\exists s \\in C2 \\gamma [s] + \\gamma' [s] \\land r= t \\| s \\}\n\n4 \\textbf{while} \\(t <> \\text{Nil} \\) \\textbf{do}\n5 \\textbf{if} \\( \\varphi [t] \\) \\textbf{then}\n6 \\textbf{while} \\(s <> \\text{Nil} \\) \\textbf{do}\n7 \\textbf{if} \\( \\gamma [s] + \\gamma' [s] \\) \\textbf{then}\n8 \\textbf{R:= R}\\cup(t \\land s)\n9 \\textbf{Get (s, C2)}\n10 \\textbf{Get (t, C1)}\n11 \\{ \\forall r \\in R : \\exists t \\in C1 \\varphi [t] \\land \\exists s \\in C2 \\gamma [s] + \\gamma' [s] \\land r= t \\| s \\}\n\\end{verbatim}\n4.3. Traversal of association\n\nApplying the *Floyd Hoare logic* to the input component as follow.\n\n\\{Condition\\} \\land \\{Invariant\\} \\{Body\\} \\{Invariant\\}\n\n\\{(t <> Nil) \\land \\forall r \\in R : \\exists t \\in C1 | \\varphi [t] \\land \\exists s \\in C2 | ( \\gamma [s] + \\gamma' [s] ) \\land r = t\\|s \\} \\text{If } \\gamma [s] + \\gamma' [s] \\text{ then } R := R \\cup (t \\|s), \\text{ Get } (s, C2), \\text{ Get } (t, C1) \\forall r \\in R : \\exists t \\in C1 | \\varphi [t] \\land \\exists s \\in C2 | ( \\gamma [s] + \\gamma' [s] ) \\land r = t\\|s\n\nThis is always true according to Section 4.1. The second part of the logic is applied and it is automatically true because:\n\n\\{Invariant\\}while(Condition)body{\\neg Condition \\land Invariant} \\text{while loop to prove the correctness of the output component of the second rule. In algorithm 21, } R \\text{ is the result set. In line two, the object set from joining } \\text{Class1 and Class2 are selected.}\n\nIn line three, the first precondition is placed. The precondition of this algorithm is } r \\text{ not null and variable } x \\text{ and comes from joining } \\text{Class1 and Class2 and satisfies the } join \\text{ condition. The rest of the line is the invariant of this algorithm. The invariant shows that all objects in the result set satisfy the } join \\text{ condition. Line three is true before entering the } while \\text{ loop. Lines four to six are the body of the output component which is explained earlier in section 3.3.1. In the case of the exit or skip loop, line seven which includes the invariant should be true. This line shows that all objects in the result set } R \\text{ satisfy the } join \\text{ condition. If this is always true, then the whole algorithm is true.}\n\nIt is assumed that \\((C1 \\bowtie C2) = \\text{SELECT * FROM Class1 Join Class2 on } \\gamma' [t] \\text{Where } \\varphi [t] \\parallel \\gamma [s] \\) \n\nIt is assumed that \\(\\gamma' [t] \\) is \\(\\gamma' [<t_1, s_1 >, <t_1, s_2 >, ..., <t_n, s_n >] \\)\nIt is assumed that $\\varphi [t_1, ..., t_n]$\nIt is assumed that $\\gamma [s_1, s_2, ..., s_n]$\nIt is assumed that $\\Phi (r)$ is $\\gamma' [t] \\land \\varphi [t] \\lor \\gamma [s]$\nIt is assumed that pre-condition is $\\forall x \\in (C1 \\bowtie C2) : \\Phi (x)$\n\nAlgorithm 21: Output component\n\nIterating over two classes of object\n\n1. $R := \\emptyset$\n2. Get $(r, C1 \\bowtie C2)$\n3. \\{ $\\forall r <> Nil \\land \\forall x \\in (C1 \\bowtie C2) : \\Phi (x) \\land \\forall r \\in (C1 \\bowtie C2) : \\Phi (r)$ \\}\n4. while $r <> Nil$ do\n5. \\hspace{1em} $R := R \\cup [r]$\n6. \\hspace{1em} Get $(r, C1 \\bowtie C2)$\n7. \\hspace{2em} $\\forall r \\in (C1 \\bowtie C2) : \\Phi (r)$\n\nThe Floyd Hoare logic is applied to the output component as follow.\n\n\\{Condition\\} $\\land$ \\{Invariant\\} \\[Body\\] \\{Invariant\\}\n\n\\{ $\\forall r <> Nil \\land \\forall x \\in (C1 \\bowtie C2) : \\Phi (x) \\land \\forall r \\in (C1 \\bowtie C2) : \\Phi (r)$ \\} \\[R := R \\cup r, Get \\ (r, C1 \\bowtie C2) \\] \\{ $\\forall r \\in (C1 \\bowtie C2) : \\Phi (r)$ \\}\n\nThe second part of the logic is automatically true as follow:\n\n\\{ Invariant \\} while (Condition) body \\{ $\\neg$ Condition $\\land$ Invariant \\}\n\n\\{ $\\forall r \\in (C1 \\bowtie C2) : \\Phi (r)$ \\} while ( $\\forall r <> Nil \\land \\forall x \\in (C1 \\bowtie C2) : \\Phi (x)$) \\[R := R \\cup r, Get \\ (r, C1 \\bowtie C2) \\] \\{ $(\\forall r : Nil \\land \\forall x \\in (C1 \\bowtie C2) \\neg \\in \\Phi (x)) \\land \\forall r \\in (C1 \\bowtie C2) : \\Phi (r)$ \\}\n\nThe invariant of the input component is $\\forall r \\in R : \\exists t \\in C1 | \\varphi [t] \\land \\exists s \\in C2 | (\\gamma [s] + \\gamma' [s]) \\land r= t||s$ performs the same operation as the invariant of the output component: $\\forall r \\in (C1 \\bowtie C2) : \\Phi (r)$. Both invariants are explaining the join operation. The input component is implemented with the nested loop and the output component is implemented with the join operation. Therefore both input\nand output components are performing the same operation.\n\n### 4.3.2 Anti-join Traversal\n\nAlgorithm 22, presents the *anti-join* input component by the *while* loop with the invariant. Line one, presents the result set $R$. Objects from *Class1* are selected in line two. Line three presents the precondition and the invariant. There is at least one object in *Class1* for precondition to be true. The invariant is true if object-set $t$ does not satisfy the *anti-join* condition $\\psi [s,t]$. Lines 4 to 11, present the body of the *anti-join* input component which is discussed in Section 3.3.2. Line 3 is correct before entering the *while* loop as the precondition is true. At the end of the algorithm the invariant is still true. This means the whole algorithm is correct. That is because after exiting the loop, the invariant still holds and moreover if the precondition in line 3 does not hold, the loop would skip. This is proved by applying the Floyd Hoare logic formal system to the algorithm.\n\n---\n\n**Algorithm 22: Input component**\n\n*Antijoin*\n\n1. $R := \\emptyset$\n2. Get $(t, C1)$\n3. Get $(s, C2)$\n4. $\\{ t <> Nil \\land \\forall t \\in R \\mid t \\notin \\psi [s,t] \\}$\n5. **while** $t <> Nil$ **do**\n 6. Found = False\n 7. Get $(s, C2)$\n 8. **while** $s <> Nil$ **do**\n 9. **if** $\\psi [s,t]$ **then**\n 10. Found = True\n 11. Get $(s, C2)$\n 12. **if** Not Found **then**\n 13. $R := R \\cup \\{t\\}$\n 14. Get $(t, C1)$\n 15. $\\{ \\forall t \\in R \\mid t \\notin \\psi [s,t] \\}$\n\n---\nThe *Floyd Hoare logic* is applied to the input component as follow.\n\n\\[\n\\{\\text{Condition}\\} \\land \\{\\text{Invariant}\\} [\\text{Body}] \\{\\text{Invariant}\\}\n\\]\n\n\\[\n\\{t \\leftrightarrow \\text{Nil}\\} \\land \\{\\forall t \\in R \\mid t \\notin \\psi [s.t]\\} \\ [\\text{Found} = \\text{True}, \\ \\text{Get} (s, C2), \\ R:=R \\cup (t), \\text{Get}(t, C1)] \\\\{\\forall t \\in R \\mid t \\notin \\psi [s.t]\\}\n\\]\n\nThe second part of the logic is applied as:\n\n\\[\n\\{\\text{Invariant}\\}\\text{while}(\\text{Condition})\\text{body}\\{\\neg \\text{Condition} \\land \\text{Invariant}\\}\n\\]\n\n\\[\n\\{\\forall t \\in R \\mid t \\notin \\psi [s.t]\\} \\text{ while } (\\{t \\leftrightarrow \\text{Nil}\\}) \\ [\\text{Found} = \\text{True}, \\ \\text{Get} (s, C2), \\ R:=R \\cup (t), \\text{Get}(t, C1)] \\{t: \\text{Nil} \\land \\forall t \\in R \\mid t \\notin \\psi [s.t]\\}\n\\]\n\nThe output component of the *anti-join* has been rewritten with *while* and the invariant which is presented by the following algorithm. In this algorithm, result-set \\( R \\) is empty before starting the loop. Object-set \\( r \\) is selected from the left-outer-join operation between Class1 and Class2((\\( C1 \\bowtie C2 \\))). Line three includes a precondition and an invariant of the algorithm. For the precondition to be true, there should be at least one object \\( r \\). If this condition becomes false the the loop is skipping and the invariant in line seven should hold. If the precondition becomes true then the invariant in line three must held. The invariant is true because after the precondition is held, each object in \\( C1 \\bowtie C2 \\), must satisfy the *anti-join* condition which is \\( \\omega [r] \\). Therefore before and after the *while* loop the invariants are held so the whole algorithm is true. The logic is applied to the algorithm to prove the correctness.\n\nIt is assumed that \\((C1 \\bowtie C2)\\) is SELECT * FROM Class1 LEFT OUTER JOIN Class2 on \\( \\omega [r] \\).\n\nIt is assumed that \\( \\omega [r] \\) is anti-join condition \\( \\text{Class2.Member}_j = \\text{Class1.Member}_i \\).\n\nThe way that the anti-join symbol is used in Algorithm 23: \n\\( (C1 \\bowtie C2) \\), is to show that the join is left-outer-join and not rigth. That’s why the join symbol is placed near C1 not C2.\n4.3. Traversal of association\n\n**Algorithm 23:** Output component\n\nAntijoin\n\n1. \\( R := \\emptyset \\)\n2. Get ( \\( r, (C1 \\bowtie C2) \\) )\n3. \\( \\{ r <> \\text{Nil} \\land \\forall r \\in (C1 \\bowtie C2) : \\omega [r] \\} \\)\n4. while \\( r <> \\text{Nil} \\) do\n5. \\( \\text{Get ( } r, (C1 \\bowtie C2) \\text{ )} \\)\n6. \\( R := R \\cup r \\)\n7. while \\( R <> \\text{nil} \\) do\n8. \\( \\text{Get ( } r, C1 \\text{ )} \\)\n9. \\( \\{ \\forall r \\in (C1 \\bowtie C2) : \\omega [r] \\} \\)\n\nThe *Floyd Hoare logic* is applied to the output component as follow:\n\n\\[\n\\{ \\text{Condition} \\} \\land \\{ \\text{Invariant} \\} \\ [\\text{Body}] \\ \\{ \\text{Invariant} \\}\n\\]\n\n\\[\n\\{ r <> \\text{Nil} \\} \\land \\{ \\forall r \\in (C1 \\bowtie C2) : \\omega [r] \\} \\ [\\text{Get ( } r, (C1 \\bowtie C2) \\text{ ), } R := R \\cup r \\] \\\\\n\\{ \\forall r \\in (C1 \\bowtie C2) : \\omega [r] \\} \\}\n\\]\n\nThe second part of the logic is:\n\n\\[\n\\{ \\text{Invariant}\\} \\text{while(Condition)body}\\{\\neg\\text{Condition} \\land \\text{Invariant} \\}\n\\]\n\n\\[\n\\{ \\forall r \\in (C1 \\bowtie C2) : \\omega [r] \\} \\text{ while } \\{ r <> \\text{Nil} \\} \\ [\\text{Get ( } r, (C1 \\bowtie C2) \\text{ ), } R := R \\cup r \\] \\\\\n\\{ r : \\text{Nil} \\land \\forall r \\in (C1 \\bowtie C2) : \\omega [r] \\} \\}\n\\]\n\nThe invariant of the input component is \\( \\forall t \\in R \\mid t \\notin \\psi [s,t] \\) which is exactly the same as the invariant in the output. In the output component, the anti-join operation is described by the *left-outer-join* and it is \\( \\forall t \\in R \\mid t \\notin \\psi [s,t] \\). Both these invariants are an explanation of the *anti-join*. So, by achieving the same invariants, the similarity of the input and output components are proved.\n4.4 Aggregation\n\nAlgorithm 24 presents the input component of an aggregation query which is already presented in Section 3.4.1 by a *While* loop. This algorithm is using the *While* loop. $R$ is the result set. Precondition and invariant is presented in line three. Lines four to seven are the body of the aggregation application. If the precondition is true then the invariant must be true before iterating the while loop. The invariant is true if all the objects in the result set satisfy the aggregation conditions. After the loop is finished, the invariant in line eight is held. This algorithm can be used for any aggregation function: Min, Max, Average and Sum.\n\nIt is assumed that $C$ is (SELECT Member$_i$ FROM Class 1)\nIt is assumed that $C'$ is (SELECT $F(y)$ FROM Class 2 WHERE condition)\nIt is assumed that $t$ is an object variable from $C$\nIt is assumed that $s$ is an object variable from $C'$\nIt is assumed that $F(y)$ is an aggregation function, for example: Count(*)\n∀$r \\in R : \\exists s \\in C' | F(y)$: for all $r$ in $R$ there is ”$s” exists in $C'$\n\n\\begin{algorithm}\n\\begin{align*}\n1 & R := \\emptyset \\\\\n2 & \\text{Get} \\ (t, C) \\\\\n3 & \\{(t <> \\text{Nil}) \\land (s <> \\text{Nil}) \\land \\forall r \\in R : \\exists s \\in C' | F(y)\\}\n4 & \\text{while} \\ t <> \\text{Nil} \\ \\text{do} \\\\\n5 & \\quad \\text{while} \\ s <> \\text{Nil} \\ \\text{do} \\\\\n6 & \\quad \\quad \\text{Get} \\ (s, C') \\\\\n7 & \\quad \\quad R := R \\cup s \\\\\n8 & \\quad \\text{Get} \\ (s, C') \\\\\n9 & \\{ \\forall r \\in R : \\exists s \\in C' | F(y) \\}\n\\end{align*}\n\\end{algorithm}\n\nApplying the *Floyd Hoare logic* to the input component as follow:\n\n{Condition} $\\land$ {Invariant} $\\{Body\\}$ {Invariant}\n4.4. Aggregation\n\n\\[\n\\{ \\{ (t <> \\text{Nil}) \\} \\land (s <> \\text{Nil}) \\} \\land \\{ \\forall r \\in R : \\exists s \\in C' | F(y) \\} \\ \\text{[}R := R \\cup s, \\text{Get}(s, C')\\}\\]\n\n\\[\n\\forall r \\in R : \\exists s \\in C' | F(y) \\}\n\\]\n\nApplying the second part of the logic:\n\n\\[\n\\{ \\text{Invariant} \\} \\text{while(Condition)body}{\\neg \\text{Condition} \\land \\text{Invariant}}\n\\]\n\n\\[\n\\{ \\forall r \\in R : \\exists s \\in C' | F(y) \\} \\ \\text{while} \\ (\\{ \\{ (t <> \\text{Nil}) \\} \\land (s <> \\text{Nil})\\}) \\ [R := R \\cup s, \\text{Get}(s, C')\\] \\}\n\n\\[\n\\{ (t: \\text{Nil}) \\land (s : \\text{Nil})\\}\n\\]\n\nThe output component of the aggregation query has been rewritten by the while loop and it includes the invariant. The output component uses \\textit{group by} clause. The invariant which is presented in line three is considered all the objects in \\(C'\\) which satisfies the aggregation condition. The same invariant is held after finishing the while loop. If the precondition becomes true, it means that there is at least an object in \\(C'\\), then the invariant must be true. After finishing or skipping the loop, the invariant is still held which means the whole algorithm is correct. The while loop is checked if the objects follow the aggregation function or not. If yes, the objects would add to the result set.\n\nIt is assumed that \\(C''\\) is \\texttt{SELECT Member\\_i, F(y) FROM Class1, Class2 WHERE condition GROUP BY Member\\_i}\n\nIt is assumed that \\(F(y)\\) is an aggregation function, for example: \\texttt{Count(*)}\n\nIt is assumed that \\(p\\) is an object variable from \\(C''\\)\n\n<table>\n<thead>\n<tr>\n<th>Algorithm 25: Output component</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Aggregation</td>\n</tr>\n</tbody>\n</table>\n\n1. \\(R := \\emptyset\\)\n2. \\(\\text{Get}(t, C'')\\)\n3. \\(\\{ (p <> \\text{Nil}) \\land \\forall r \\in R : \\exists p \\in C'' | F(y) \\} \\)\n4. \\texttt{while \\ (t <> Nil) do}\n5. \\[ R := R \\cup p \\]\n6. \\(\\text{Get}(p, C'')\\)\n7. \\(\\{ \\forall r \\in R : \\exists p \\in C'' | F(y) \\} \\)\nThe *Floyd Hoare logic* is applied to the output component as follow:\n\n\\[\n\\{\\text{Condition}\\} \\land \\{\\text{Invariant}\\} \\ [\\text{Body}] \\ [\\text{Invariant}] \\\\\n\\{ \\ (p <> \\text{Nil}) \\} \\land \\{ \\forall r \\in R : \\exists p \\in C'\\mid F(y) \\} \\ [R := R \\cup p, \\text{Get}(p, C')] \\ [\\forall t \\in C' : F(y) \\} \\\\\n\\]\n\nApplying the second part of the logic:\n\n\\[\n\\{\\text{Invariant}\\} \\text{while}(\\text{Condition}) \\text{body}\\{ \\text{Condition} \\land \\text{Invariant} \\} \\\\\n\\{ \\forall r \\in R : \\exists p \\in C'\\mid F(y) \\} \\text{ while } \\{(p <> \\text{Nil})\\} \\ [R := R \\cup p, \\text{Get}(p, C')] \\ {\\forall t \\in C' : F(y) \\} \\\\\n\\]\n\nAll of the algorithms are overwritten using *while* loop to be able to use the *Floyd Hoare logic*. The invariant of both the input and the output components of the rule are the same. It can be concluded that these two algorithm are the same by having the same invariant for the input and output component of this rule. \\( \\{ \\forall r \\in R : \\exists s \\in C'\\mid F(y) \\} \\) is the invariant of the input component and the same invariant with different SELECT statements is used for the output component: \\( \\{ \\forall r \\in R : \\exists p \\in C'\\mid F(y) \\} \\). As explained earlier, \\( F(y) \\) is referring to the aggregation function. This means that both invariants of the input and the output algorithm are performing the same functions and as a result both invariants and both algorithms are same.\nChapter 5\n\nCode Templates\n\n5.1 Introduction\n\nAn input component of any transformation rule is a non-optimised version of the OR application. This application is written by an OO developer and is based on iteration over a class of objects. An input component is required to use the transformation rules. The problem is that the application developers can design applications in different ways. Different rules are verified to cover all possible cases.\n\nTo solve this problem, certain Java patterns were proposed which individual JPA programmers can use to write an OO application. By having certain patterns for the input components of the rules, the analysis of the source code will be easier. The proposed templates can be used to match the implementation of the current OO programs. The majority of OR database applications are combinations of the following styles, so the transformation rules are applicable to them.\n\nEach transformation rule presented in Chapter 3 includes an input and output component. The input component which is a non-optimised version of the application has to find the relevant transformation rule. In this section, each input component is presented by a code template. This makes the process of finding the correct output component easier.\n\nThe following styles are based on the Java programming language and are similar to most of the other OO languages. Application programmers can match their applications with the following Java templates. Depending on the application, the name of the classes of objects, the aggregation functions, the relational conditions and the non-relational conditions will change. OO programmers have to replace the\nstatement inside ' < > ', with the appropriate statement of their code. The statements in ' [ ] ' are optional. Other parts of the template remain unchanged. The syntax of relational and non-relational conditions are already explained in Chapter 3, to avoid repetition they will not be explained here again.\n\n5.2 Filtering Template (F.Temp)\n\nThe input component of the first transformation rule is consistent with the following template.\n\n```java\n{ \n Query query1 = em.createQuery(<Any SQL SELECT statement>); \n List list1 = query1.getResultList(); \n Iterator iterator1 = list1.iterator(); \n while(iterator1.hasNext()){ \n { \n if <CONDITIONS> then \n <Java code>; \n } \n } \n}\n```\n\nWhere <CONDITIONS> is a type of filtering condition for the class which filter the output. For instance: `l.partsupp = 900`. This condition means that, the objects in `l.partsupp` which have equal value to \"900\" will be selected for the output result from the class.\n\n5.3 Traversal of Association\n\n5.3.1 Join Traversal of Association Template (TA.Temp)\n\nThe output component which is presented in Section 3.3.2 is the optimised version of the application, only if the input component matches the following style.\n{ \nQuery query1 = em.createQuery(\n \"SELECT statement from CLASS1\" + [ NON-RELATIONAL CONDITIONS of CLASS1]);\n<GET VARIABLE> ; \nList list1 = query1.getResultList();\nIterator iterator1 = list1.iterator();\nwhile(iterator1.hasNext())\n{\n <VARIABLE> = list1.getInt(1);\n if <CONDITIONS> then \n {\nQuery query2 = em.createQuery(\n \"SELECT statement from CLASS2\"\n \"RELATIONAL CONDITIONS\");\nList list2 = query2.getResultList();\nIterator iterator2 = list2.iterator();\nwhile (iterator2.hasNext())\n{\n if <RELATIONAL CONDITIONS of CLASS2> then\n <Java code>;\n }\n}\n}\n\nWhere <RELATIONAL CONDITIONS> are join conditions. An example of <RELATIONAL CONDITIONS> is: l.l_suppkey = s.s_suppkey. This join condition finds the values of l_suppkey from Lineitem class which are same as s.s_suppkey in Supplier class. The <VARIABLE> is used to retrieve the results in <Java code>.\nAn example of <RELATIONAL CONDITIONS> is: l.l_suppkey = s.s_suppkey. It is assumed that l is an object variable from class1 and s is an object variable from class2.\n\nAn example of <NON-RELATIONAL CONDITIONS> : l.l_suppkey = 423 or s.s_suppkey = 533\n5.3.2 Anti-Join Traversal of Association Template (AJ.Temp)\n\nIf the input component of the rule matches any of these two anti-join styles then it can be modified according to the rule presented in Section 3.4.3.\n\n**Style 1**: This style of anti-join input component uses a variable. In the following pattern, VAR is referred to as a variable. The variable is *false* before entering the second *while* loop. The variable will become *true* for each object which satisfies the `<Anti-join Condition>`. As a result, only objects which do not satisfy the `<RELATIONAL CONDITIONS>` would be in the output.\n\n```java\n{\n Query query1 = em.createQuery(\n '<SQL SELECT statement from CLASS1>);\n GET VAR = false ;\n List list1 = query1.getResultList();\n Iterator iterator1= list1.iterator();\n while(iterator1.hasNext()){ \n Query query2 = em.createQuery(\n '<SQL SELECT statement from CLASS2>\n where\n <ANTI-JOIN CONDITION>;\n List list2 = query2.getResultList();\n Iterator iterator2= list2.iterator();\n while (iterator2.hasNext())\n {\n if <ANTI-JOIN CONDITION>{\n VAR = True;\n Exit;\n } \n } \n if VAR==false\n {\n <Java code>;\n }\n}\n```\n\n*Style 1* can also be defined as follows:\n5.3. Traversal of Association\n\n{ \n Query query1 = em.createQuery( \n \"SELECT statement from CLASS1\" \n ); \n List list1 = query1.getResultList(); \n Iterator iterator1= list1.iterator(); \n while(iterator1.hasNext()) \n { \n Query query2 = em.createQuery( \n \"SELECT statement from CLASS2\" \n ) \n where \n \"Anti-join Condition\"; \n List list2 = query2.getResultList(); \n Iterator iterator2= list2.iterator(); \n if List2.IsEmpty() \n { \n <Java code>; \n } \n } \n }\n\nStyle 2: In this style, the programmer is using a counter. The counter checks if any object satisfies the anti-join condition.\n\n{ \n Count=0 \n Query query1 = em.createQuery( \n \"SELECT statement from CLASS1\" \n ); \n List list1 = query1.getResultList(); \n Iterator iterator1= list1.iterator(); \n while(iterator1.hasNext()) \n { \n Query query2 = em.createQuery( \n SELECT Count(*) FROM <CLASS2> \n where \n \"Anti-join Condition\"; \n int Count = query1.getSingleResult(); \n if Count == 0 \n }\n5.4 Aggregation Template (AG.Temp)\n\nThe template used for the aggregation rule is presented below. If the input component matches the following template, the aggregation output component which is presented in 3.5.2 is the optimised version of application. F(x) can be any type of the aggregation function: Min, Max, Sum, Avg or Count.\n\n[CONDITION] is not compulsory for being in the template. It depends on the application. [CONDITION] is any condition between two classes. For example: l.emp-num = s.emp-num.\n\n```java\n{ Query query1 = em.createQuery\n (\"SELECT <Memberi> FROM <CLASS 1>\");\n List list1 = query1.getResultList();\n Iterator iterator1= list1.iterator();\n while(iterator1.hasNext())\n {\n Query query2 = em.createQuery\n (\"SELECT <F(x)>\n FROM <CLASS 2>\n WHERE\n [CONTITION] \");\n List list2 = query2.getResultList();\n Iterator iterator2= list2.iterator();\n while (iterator2.hasNext())\n {\n <Java code>;\n }\n }\n}\n```\n5.5 \\( n \\) Associations Template\n\nThe application developers distinguishes the template of their application in order to use one of the rules explained in Chapter 3. The \\( n \\) Associations Template rule are described in this section for the developers to build the application template step by step. Then the rules are applied to the application and as a result the optimised version of the application is obtained.\n\nIt is assumed that \\( F \\) is : Filtering, \\( C \\) is : Condition, \\( J \\) is : Java Code, \\( JC \\) is : Join Conditions, \\( V \\) is : Variable, \\( A \\) is : Array, \\( AGC \\) is : Aggregation Conditions and \\( OV \\) is an Object Variable. The \\( OV \\), keeps the results from one template and passes it to the other template. The object variable takes the results from each template and passes it to the next template. At the end of each template, the object variable is updated to the new object variable which includes new results from the current template and this object template is ready to be used in the next template. So generally all of the templates can be presented as short templates as follows:\n\n\\[\n\\begin{align*}\nT_F &< F, C, OV, J > \\\\\nT_{TA} &< F_1, F_2, C, JC, OV, J > \\\\\nT_{AJ} &< F_1, F_2, C, OV, J > \\\\\nT_{AG} &< A, F, AGC, OV, J >\n\\end{align*}\n\\]\n\nThe template of each association has to be created and linked together by an object variable for making the template for \\( n \\) associations. In this regard, the 'Java Code' (\\( J \\)) as a part of the short template, must be replaced by the next desire short template. Also, the object variable (\\( OV \\)) from the first template must keep the result of that template and pass it to the next template as the input of the class. This means that the result of each template is kept and stored as \\( OV \\). In the next template one of the classes modifies and receive the values from \\( OV \\).\n\n5.5.1 Simple Associations\n\nFor instance, assume that there are 3 classes: Student Name/Class1, Course/Class2, Marks/Class3 and the programmer would like to find all student names which are \"Arash\". The next step is to find who does not take Maths and then find who gets a mark above 50 in those other courses. In this case, there is filtering at the\nbeginning for class1, then an anti-join of class1 and class2 and at the end association of traversal between class2 and class3. The following template for this example is designed by using the above short templates:\n\n\\[ T_F < F, C, OV_1, < T_{A J} >> .... T_{F,A J} < F, C, < OV_1, F_2, C, OV_2, J >> .... T_{F,A J,T A} < F, C, < OV_1, F_2, C, JC, < OV_2, F_3, C, JC, OV, J >> > > > \\]\n\n\\[ ((SELECT (Student) ANTIJOIN (Course)) JOIN (MARKS)) \\]\n\nThe actual templates which are presented in Sections 5.2, 5.3 and 5.4 are replaced by the very last short template \\((T_{F,A J,T A} < F, C, < OV_1, F_2, C, JC, < OV_2, F_3, C, JC, OV, J >> > > >)\\), so the final template is created as follow:\n\n```java\n{\\filtering template\\\\\nGet OV;\nQuery query1 = em.createQuery(<SELECT * FROM student s WHERE s.s-name = \"Arash\" >);\nList list1 = query1.getResultList();\nIterator iterator1= list1.iterator();\nwhile(iterator1.hasNext())\n{\n if <CONDITIONS> then\n {\n Update OV to OV1;\n \\RESULT = OV1\\\\\n\n \\OV1 is now includes the students from\n \\the 'student' class which have \"Arash\" name.\\\\\n\n \\Anti join template\\\\\n\n \\Passing OV1 to the new template\n \\ as the value of Class1\\\\\n \\Instead of doing Antijoin between\n \\student and course classes,\n \\ the antijoin would happen between the result of\n```\n5.5. *n Associations Template*\n\n```\n\\\\ the previous template\n\\\\ which is already saved in the\n\\\\ object variable 'OV1' and the 'course' class\\\\\n\nGet OV1;\nQuery query2 = em.createQuery(\n SELECT ov1 from OV1);\nList list1 = query2.getResultList();\nIterator iterator2= list1.iterator();\nwhile(iterator2.hasNext())\n{\n Query query3 = em.createQuery(\n SELECT c from course c WHERE\n c.c-name=\"Math\" AND c.course=ov1.c-id=c.c-id)\n List list2 = query3.getResultList();\n Iterator iterator3= list2.iterator();\n If list2.isEmpty()\n {\n Copy ov1 to OV2;\n \\At this point,\n \\all the students with name \"Arash\"\n \\whom does not take\n \\course \"Math\" are selected\n \\ and placed into OV2\\\\\n\n \\Join template\\\\\n\n \\Passing OV2 to the new template,\n \\ so that the result of antijoin\n \\ 'student' and 'course'\n \\ would be join to the 'marks' class\\\\\n\n Get OV2;\n Query query4 = em.createQuery(\n SELECT ov2 from OV2);\n List list4 = query4.getResultList();\n```\nIterator iterator4 = list1.iterator();\nwhile (iterator4.hasNext())\n{\n Query query5 = em.createQuery(\n <SELECT c from course c >\n WHERE\n <ov2.c-id= m.m-id AND m.m-mark > 50>);\n List list5 = query5 resultList();\n Iterator iterator5 = list5.iterator();\n while (iterator5.hasNext())\n {\n copy ov2 to OV3;\n\n \\Now OV3 include the all the\\n \\students with name \"Arash\"\\n \\ whom not got \"Math\" and\\n \\ got mark above 50 in the other courses\\\\\n\n <Java code>; } }}\n\n} \n\nThe inner loops results must be calculated and passed to the outer loops for a more complex query.\n\nFor instance, if the case is : FILTERING(FILTERING(A JOIN B) ANTIJOIN (C JOIN D))\n\nthen the template for the application must be implemented in the following way:\n\nFILTERING {\n ANTIJOIN {\n FILTERING {\n JOIN (A,B) {\n } RESULT OV1\nAlternatively, this can be done as follow:\n\n\\[\n\\text{JOIN (A,B) \\{ \\\\\n\\text{\\quad RESULT OV1} \\\\\n\\text{\\}}}\n\\]\n\n\\[\n\\text{FILTERING (OV1) \\{ \\\\\n\\text{\\quad RESULT OV2} \\\\\n\\text{\\}}}\n\\]\n\n\\[\n\\text{JOIN (C,D) \\{ \\\\\n\\text{\\quad RESULT OV3} \\\\\n\\text{\\}}}\n\\]\n\n\\[\n\\text{ANTIJOIN (OV2, OV3) \\{ \\\\\n\\text{\\quad RESULT OV4} \\\\\n\\text{\\}}}\n\\]\n\n\\[\n\\text{FILTERING (OV4) \\{ \\\\\n\\text{\\quad RESULT OV5} \\\\\n\\text{\\}}}\n\\]\n\nFigure 5.1 illustrates the symbolic tree of the OR application. This tree has three levels. Both join and anti-join patterns are applied to the tree. The patterns must start to apply from the inner nodes. In this tree, each two pairs of nodes will be transferred into one node. Generally this tree presents the process of applying the patterns step by step. Each level includes two nodes and each node represents a SELECT statement which is a part of the OR application. The join template is applied to the nodes on the left side of the main branch. On the right branch the anti-join template is applied.\n5.5. $n$ Associations Template\n\nWhere the outermost SELECT statement is $S$ and all other SELECT statements in the branches are $s$. Applying the templates has to be started from the two innermost SELECT statements. At the end, there will be only one SELECT statement. This new SELECT statement is used in the join/anti-join clause with the other innermost SELECT statements.\n\n5.5.2 Complex Associations\n\nIn this section, a complex query implemented based on the $n$ associations rule.\n\nIn this example it is assumed that there are 5 classes: Student/Class1, Enrollment/Class2, Course/Class3, Marks/Class4, Faculty/Class5. The programmer would like to find all the student names who have already enrolled. For this step, a filtering template is used to select all students and a join template is used to find the enrolled students.\n\nThe next step is to find who enrolled in 'Science'. Therefore, the result of the previous query needs to join with the course class. For this, the TA template is used.\nNow, from the result of previous queries, we are able to find who did not pass that course. Therefore, an antijoin template (AJ) is needed here. Also, we are able to find which faculty the failed students belong to and at the end of the programme count the number of failed students. To implement this part of the query, one join with faculty class and one aggregation template to count the number of students is used.\n\nTo implement the above query based on short templates which are presented in section 5.5, the following query needs to be executed:\n\n\\[\n(((\\text{SELECT (Student) JOIN (Enrolment)) JOIN(Course)) \\text{ AntiJOIN (Marks)}) \\text{ Aggregate (Faculty)})\n\\]\n\nThe following short template replaced in the above query should be provided in the correct order.\n\nShort templates:\n- \\( T_F < F, C, OV, J > \\)\n- \\( T_{TA} < F_1, F_2, C, JC, OV, J > \\)\n- \\( T_{AJ} < F_1, F_2, C, OV, J > \\)\n- \\( T_{AG} < A, F, AGC, OV, J > \\)\n\nApply short templates:\n\n1. \\( T_F < F, C, OV1, < T_{J} >> .... \\)\n2. \\( T_{F,T_A} < F, C, < OV1, F_2, C, JC, OV2, J >> .... \\)\n3. \\( T_{F,T_A,T_A} < F, C, < OV1, F_2, C, JC, < OV2, F_3, C, JC, OV3, J >>> .... \\)\n4. \\( T_{F,T_A,T_A}, A_J < F, C, < OV1, F_2, C, JC, < OV2, F_3, C, JC, < OV3, F_4, C, OV4, J >>>>> .... \\)\nFirst the filtering template presented (presented in 1). Then, the join template placed instead of OV of the previous template (presented in 2). Then another join template placed instead of OV2 (presented in 3). Next, to present the anti-join, an anti-join pattern is replaced instead of OV3 (presented in 4). Finally, an aggregation template is replaced instead of OV3. The output of the whole query returned by OV4 (presented in 5). The actual templates which are presented in Section 5.2, 5.3 and 5.4 are replaced in the above short template to create the actual final template of the complex query. So the final template is created as follows:\n\n```\n{\n \\Filtering template\\n Get OV;\n Query query1 = em.createQuery(<SELECT * FROM student s>);\n List list1 = query1.getResultList();\n Iterator iterator1 = list1.iterator();\n while(iterator1.hasNext())\n {\n if <CONDITIONS> then\n {\n Update OV to OV1;\n \\RESULT = OV1\\n }\n \\OV1 is now includes the students\n \\ from the 'student'.\\n\n \\Join template\\n\n \\Passing OV1 to the new template\n \\as the value of Class1\\n \\Instead of doing Join between\n \\student and enrolment classes,\n \\the Join would happen between\n \\the result of the previous template\n \\which is already saved in the\n \\object variable 'OV1' and the 'enrolment' class\\n\n```\nGet OV1;\nQuery query2 = em.createQuery(<SELECT ov1 from OV1>);\nList list2 = query2.getResultList();\nIterator iterator2 = list2.iterator();\nwhile(iterator2.hasNext())\n{\nQuery query3 = em.createQuery(<SELECT e from enrolment e WHERE e.enrolment.status = 'Y' AND e.enrolment.id = ov1.s-id >\nList list3 = query3.getResultList();\nIterator iterator3 = list3.iterator();\nIf list3.IsEmpty()\n{\nCopy ov1 to OV2;\n\\At this point,\n\\all the students who are\n\\already enrolled are selected\n\\and placed into OV2\\n\\Second Join template\\n\\Passing OV2 to the new template,\n\\the result of the first join\n\\'student' and 'enrolment'\n\\would be joined to the 'course' class\\n\nGet OV2;\nQuery query4 = em.createQuery(<SELECT ov2 from OV2>);\nList list4 = query4.getResultList();\nIterator iterator4 = list4.iterator();\nwhile(iterator4.hasNext())\n{\n Query query5 = em.createQuery(\n <SELECT c from course c >\n WHERE\n c.course-name=science AND\n ov2.s-id= c.c-id>);\n List list5 = query5.getResultList();\n Iterator iterator5= list5.iterator();\n while (iterator5.hasNext())\n {\n copy ov2 to OV3;\n \\\n \\Now OV3 includes all the\n \\students who are already enrolled\n \\and studying the science course\\n\n \\\\Anti join template\\n\n \\\\Passing OV3 to the new template\n \\\\the antijoin would happen between\n \\\\the result of the previous template\n \\\\which is already saved in the\n \\\\object variable 'OV3'\n \\\\and the 'Mark' class\\n\n Get OV3;\n Query query6 = em.createQuery(\n <SELECT ov3 from OV3>);\n List list6 = query6.getResultList();\n Iterator iterator6= list6.iterator();\n while(iterator6.hasNext())\n {\n Query query7 = em.createQuery(\n <SELECT m from marks m WHERE\n m.mark=>50>\nList list7 = query7.getResultList();\nIterator iterator7 = list7.iterator();\nIf list7.isEmpty()\n{\n Copy ov3 to OV4;\n \\At this point,\n \\all the students\n \\who does not achieve\n \\the pass mark are selected\n \\and placed into OV4\\\\\n\n \\Aggregation template\\\\\n\n \\Passing OV4 to the new template\n \\the aggregation would happen between\n \\the result of the previous template\n \\which is already saved in the\n \\object variable 'OV4'\n \\and the 'faculty' class\\\\\n\n Query query8 = em.createQuery\n(\"SELECT ov4 FROM OV4\");\nList list8 = query8.getResultList();\nIterator iterator8 = list8.iterator();\nwhile (iterator8.hasNext())\n{\n Query query9 = em.createQuery\n(\"SELECT <count(*)>\nFROM f from faculty f WHERE\n<f.faculty-name=ov4.m-id>\");\nList list9 = query9.getResultList();\nIterator iterator9 = list9.iterator();\nwhile (iterator9.hasNext())\n{\n <Java code>; } } } } } } }\nDesigning a tool which can implement the final template automatically, remains to be determined in future work on this system.\nChapter 6\n\nExperimental Results\n\nThe results of the experiments conducted are presented in this section. Real applications are tested for both input and output components of each group of the transformation rules. The total number of Blocks-Read operations and also run-time of the applications accessing the different size databases are compared for the first set of experiments. The rest of the experiments compared only the run-time of the applications before and after transformation. The experiments are conducted using the TPC-H Benchmark database which has 300 MB relational data. The Lucid Lynx Ubuntu system running on 3.33 GHz Intel(R), Core(TM)2, Duo CPU with 3.25 GB RAM is used to run the applications. In all of the following examples, a class Supplier and a class Lineitem are used for the experiment. Class Supplier consists of 3000 objects while the Lineitem class includes objects varies between 400,000 objects to 1,800,000 objects.\n\nThe netbeans run-time clock used to measure the run-time of application. The netbeans run-time clock calculates the application’s run-time regardless of the network and server traffic by using a byte-count as the basis of its measurement. It measures the amount of data (in bytes) that is processed and/or transmitted. Hence, the measurement is independent to the server load and to the state of the network. A couple of examples were run using both netbeans run-time and wall-clock. The results of the netbeans run-time clock were consistent and reasonable. However, the run-time calculated by the wall-clock were fluctuated and were completely different than the real runtime.\n\nThe class Supplier and Lineitem class were Oracle database tables. Considering this thesis supports the OR application, all the tables are converted to java classes of objects within the Java programming language (Java Persistence API (JPA)). This\nconversion is supported by the netbeans environment. The number of objects in each class is considered as the size of the class. Appendix A gives the source code of class Supplier and class Lineitem.\n\nThe Java Persistence API (JPA) is a Java specification for accessing, persisting, and managing data between Java objects / classes and a relational database. JPA was defined as part of the EJB 3.0 specification as a replacement for the EJB 2 CMP Entity Beans specification.\n\nAll of the examples were tested in JPA and in the NetBeans IDE 7.1.2 environment. The Lineitem and Supplier classes in JPA format and also persistence source file are presented in the appendix section.\n\nFigures 6.2 and 6.4 present the average results of Blocks-Read for a different number of objects in the Lineitem. The trend line has been incorporated as a polynomial function in order of two for the prediction of the number of blocks read. The trend line (stated as a line of best fit) is a curve that is used to exemplify the behaviour of a set of data to determine if there is a specified pattern. This trend line is an analytical tool on these two-dimensional graphs, to determine the relationship between the number of Blocks-Read and number of objects in the Lineitem variables as presented by the equation.\n\nThe error bar has also been inserted for each point. As mentioned before the mean value is plotted for reading of blocks which was calculated for each number of objects in the Lineitem by using the AVERAGE function in Excel. In order to reflect the true values, additional information as an error bar is included. There are two ways to describe uncertainty in the presented data. One is with the standard deviation of a single measurement and the other is with the standard deviation of the mean. The second way is known as the standard error and has been incorporated, since the means were shown in the graphs.\n\nFirst the standard deviation with the STDEV function was calculated. The standard error was also calculated by dividing the standard deviation by the square root of the number of measurements that make up the mean which for this purpose is 4.\nFigures 6.1, 6.3, 6.5, 6.6, 6.7 and 6.8, show the average of the execution times for a different number of objects in the Lineitem. The figures show the result of the running optimise and non-optimise applications in different structures. The trend line has been incorporated as a polynomial function in the order of two for the prediction of the execution time for a larger number of objects in the Lineitem. The error bar has also been inserted at each point.\n\n6.1 Motivation Experiment/Join Traversal\n\nApplication A is written in Java. This is an example of nested iterations over two classes of objects, called Lineitem and Supplier. The algorithm count and retrieves all values from l.sSuppkey in the Lineitem class which has equal values to s.sSuppkey in the Supplier class. Therefore, joining the classes is required. In this application, join operation is designed by nested loops. Each object is compared with an entire class by writing join operation with nested loops. Objects which satisfy the join condition of two classes are retrieved by running this application. In Application A, a nested loop join iteratively steps through objects from an outer class and reference objects from an inner class join with the current object from the outer class. Each candidate object in the outer class must be iterated before it can be eliminated by the join condition with the inner table by writing join operation based on nested loops. In Application A, there is an unnecessary overhead to process all of the objects as part of the join process. Application A retrieves the same objects in sSuppkey from both classes as well as the results of counting them. Application A is presented as a nested loop join as follow:\n\nApplication A:\n\n* @author ZahraDavar(zd991)\n\npackage Demo;\n\nimport java.math.BigDecimal;\nimport javax.persistence.EntityManager;\nimport javax.persistence.EntityManagerFactory;\nimport javax.persistence.EntityTransaction;\nimport javax.persistence.Persistence;\nimport javax.persistence.Query;\nimport java.util.List;\nimport java.util.Iterator;\n\npublic class NewMain1 {\n public static void main(String arg[]){\n EntityManagerFactory emf =\n Persistence.createEntityManagerFactory(\"newprojectjpa2PU\");\n EntityManager em = emf.createEntityManager();\n try{\n EntityTransaction entr = em.getTransaction();\n entr.begin();\n\n Query query1 = em.createQuery\n (\"SELECT s FROM Supplier s\", Supplier.class);\n List list1 = query1.getResultList();\n Iterator iterator1 = list1.iterator();\n while(iterator1.hasNext())\n {\n Supplier s = (Supplier)iterator1.next();\n Long item = s.getsSuppkey();\n Query query2 = em.createQuery\n (\"SELECT l FROM Lineitem l\n WHERE\n l.sSuppkey = s.sSuppkey\", Lineitem.class);\n List list2 = query2.getResultList();\n Iterator iterator2 = list2.iterator();\n int counter = 0;\n if (!list2.isEmpty())\n {\n while (iterator2.hasNext())\n {\n Lineitem l = (Lineitem)iterator2.next();\n counter ++;\n }\n }\n }\n }\n }\n}\nIn order to test the performance of Application A, the total number of Blocks-Read operations and the response time was measured for each time running of the application with different size databases. The Blocks-Read operations were measured by using Oracle’s UTLBSTAT/UTLESTAT scripts to take a snapshot of program activity. It collects instance related performance data. Also, the Netbeans run-time clock was used to measure the run-time.\n\nExperiments started by class Lineitem with 400,000 objects and it was gradually increased to 1,800,000 objects. In all of the experiments, size of class Supplier was constant at 3000 objects. Figure 6.1 shows the different run-time achieved by running Application A with different size database. The response time starts from approximately 1 hour for 400,000 objects in the class Lineitem and increases to almost 6 hours with almost 1,800,000 objects in the class Lineitem.\nFigure 6.1: Execution Time for Application A\n\nFigure 6.2 illustrates the total number of Blocks-Read operations occurring for the performance of the Application A with different sizes of the Lineitem class. The number of Blocks-Read operations for running Application A started from approximately 92 million blocks for 400,000 objects and ended up with almost 108 million blocks for 1,800,000 objects. The results are shown in the chart in Figure 6.2.\nFigure 6.2: Number of Blocks-Read for application A\n\nFigure 6.1 and Figure 6.2 show that the increase of the size of the database rises the total number of the Blocks-Read operation and run-time of Application A. Also, it can be concluded that the performance problem of this application with a larger database increases exponentially. This implementation leads to read 1,800,000 objects from the database which is a substantial amount of data. Therefore, the join condition is applied to all transferred objects from the server side to the client side. Application A is restructured as shown in Application B to make this application more efficient. Application B has the same output as Application A with a different structure. Application B presents join operation with JOIN clause as follow:\n\n**Application B:**\n\n* @author ZahraDavar(zd991)\n\n```java\npackage Demo;\n\nimport java.math.BigDecimal;\nimport javax.persistence.EntityManager;\nimport javax.persistence.EntityManagerFactory;\nimport javax.persistence.EntityTransaction;\nimport javax.persistence.Persistence;\n```\nimport javax.persistence.Query;\nimport java.util.List;\nimport java.util.Iterator;\n\npublic class NewMain {\n public static void main(String arg[]){\n EntityManagerFactory emf=\n Persistence.createEntityManagerFactory(\"newprojectlibraryPU\");\n EntityManager em=emf.createEntityManager();\n try{\n EntityTransaction entr=em.getTransaction();\n entr.begin();\n\n Query query = (Query) em.createQuery\n (\"SELECT l.sSuppkey,\n COUNT(*)\n FROM Lineitem l\n JOIN Supplier s on\n l.sSuppkey = s.sSuppkey\", Lineitem.class);\n\n List list1 = query.getResultList();\n Iterator iterator1= list1.iterator();\n Long ps_suppkey = s.getsSuppkey();\n\n while(iterator1.hasNext()){\n int counter = 0;\n if (!list1.isEmpty()){\n Lineitem l= (Lineitem)iterator1.next();\n counter ++;\n }\n\n System.out.println( ps_suppkey + \" \" + counter);\n }\n }\n }\n}\n\nfinally{\n em.close();\n}\nApplication B uses one `SELECT` statement. Application B with more OQL statements, changes the balance of the data-processing. It reduces the total number of objects transferred from the server side to the client side. Therefore, the unnecessary iterations and data transmission are eliminated. With Application A, the total number of `Blocks-Read` operations and the response time for different size `Lineitem` were measured for Application B.\n\nFigure 6.3, illustrates the execution time required to run application B with different sizes of the `Lineitem` class. Application B performed with 400,000 objects in `Lineitem` and increased the objects up to 1,800,000. The results are evidenced in the chart shown as Figure 6.3. The runtime of application B varied between 2 to 4 seconds.\n\nApplication B is more efficient than application A. This application requires a few objects to contribute to the final result. Since in Application A, the `join` condition is applied to all objects regardless of the need for them in the final result.\nFigure 6.4 illustrates the total number of Blocks-Read operation performed by Application B. The number of Blocks-Read operations performed by Application B, started from 30,000 blocks for 400,000 objects in the Lineitem class and increased to almost 32,000 blocks for 1,800,000 objects. These results show that the increase in the size of the database raises the number of Blocks-Read operation. Also comparing Figure 6.4 with Figure 6.2 shows that the number of Blocks-Read operation for Application B is significantly less than for Application A.\n\n\n\nFigure 6.4: Number of Blocks-Read for application B\n\nThe considerable performance difference between these two implementation is visible by comparing the run-time results of Application A and B which were presented in Figure 6.1 and Figure 6.3. Run-time for Application A exponentially increased from one to six hours, since the same output as Application A is achieved from Application B, with the linear chart and between 2 to almost 4 seconds. To analyse the result, the run-time of both applications for the smallest size and the largest size database were compared. For the Lineitem class including 400,000 objects, running Application A took one hour, whereas Application B run in only two seconds. It can be concluded that run-time of Application B, was 1,800 times faster than Application A with 400,000 objects in Lineitem class.\n\nFor the Lineitem class with 1,800,000 objects, Application A took six hours to produce the output while Application B required just four seconds. Application B\nwas 5400 times faster than Application A with the same size database.\n\nThe run-time results of Application A had an exponential growth while run-time of Application B increased linearly, it can be concluded that the performance difference between these two applications are growing exponentially from 400,000 to 1,800,000 objects. Therefore, Application B is much more scalable than Application A.\n\nAlso, the number of blocks read in Application A was at least 92,000,000 blocks, whereas Application B covered around 30,000 blocks. The significant difference shows that there is no need to read a huge amount of data by restructuring Application A to Application B. Therefore, by comparing all of the results from both applications, it can be concluded that the change in the structure of Application A so that only 300MB data is transmitted to the client side instead of 3GB (1000 times less).\n\n6.2 Anti-Join Traversal\n\nThe same classes used in the motivation experiments were employed for running the anti-join applications such as Lineitem and Supplier class. An anti-join between two classes returns objects from the first class where there is no similarity in the second class. As all the objects in the Supplier class existed in the Lineitem class, to get an output from the anti-join application, first all objects with value of '199' from Lineitem class are removed. The following SQL code was performed before running the first anti-join application:\n\n\"DELETE FROM CSCI315.LINEITEM where L_SUPPKEY=199\"\n\nAfter removing all the objects which had equal value to 199, the maximum size of the Lineitem class changed to 1,700,000 objects.\n\nApplication C presents an anti-join structure. In Application C, the outer loop receives all the objects from the Supplier class. The inner loop collects all the L_SUPPKEY from the Lineitem class which is matched with S_SUPPKEY from the Supplier class. Application C, retrieves all values in L_SUPPKEY from the Lineitem class which do not have the same value in S_SUPPKEY from Supplier class. By using the default database, the output is 199. Application C is implemented by nested SELECT statements.\n6.2. Anti-Join Traversal\n\nApplication C\n\n* @author ZahraDavar(zd991)\n\n```java\npackage Demo;\nimport java.math.BigDecimal;\nimport javax.persistence.EntityManager;\nimport javax.persistence.EntityManagerFactory;\nimport javax.persistence.EntityTransaction;\nimport javax.persistence.Persistence;\nimport javax.persistence.Query;\nimport java.util.List;\nimport java.util.Iterator;\n\npublic class NewMain {\n public static void main(String arg[]){\n EntityManagerFactory emf=\n Persistence.createEntityManagerFactory(\"newprojectjpa2PU\");\n EntityManager em=emf.createEntityManager();\n try{\n EntityTransaction entr=em.getTransaction();\n try{\n entr.begin();\n Query query1 = em.createQuery\n (\"SELECT s FROM Supplier s\", Supplier.class);\n List list1 = query1.getResultList();\n Iterator iterator1= list1.iterator();\n System.out.println(\"Check existence of supplier's data in lineitem class\");\n while(iterator1.hasNext()){\n Query query2 = em.createQuery\n (\" SELECT l FROM Lineitem l\n```\nWHERE l.L_SUPPKEY=\" +query1.getInt(\"s.S_SUPPKEY\", Lineitem.class));\nList list2 = query2.getResultList();\nIterator iterator2= list2.iterator();\n if (List2.isEmpty())\n {\n System.out.println(list1.getInt(\"s.S_SUPPKEY\"));\n }\nfinally{\n em.close();\n}\n\nThe run-time of the application with different sizes of the class \\textit{Lineitem} is recorded to test the performance of Application C. One of the outputs of running the above application in Netbeans with almost 1,700,000 objects in \\textit{Lineitem} class is as follows:\n\n\\begin{verbatim}\nrun:\nCheck existence of supplier's data in lineitem class\nITEM 199 not exist in LINEITEM\nBUILD SUCCESSFUL (total time: 134 minutes 54 seconds)\n\\end{verbatim}\n\nFigure 6.5 shows the result of running the nested loop structure of the \\textit{anti-join} application with different sized \\textit{Lineitem} class. The run-time of Application C started from 1 hour for 400,000 objects in the \\textit{Lineitem} class and increased to approximately 3 hours for 1,700,000 objects.\n6.2. Anti-Join Traversal\n\nFigure 6.5: Execution Time for Application C\n\nApplication D is a restructured version of Application C. Application D implemented anti-join by the left outer join clause. This application produces the same output as Application C.\n\nApplication D:\n*\n\n```java\npackage Demo;\nimport java.math.BigDecimal;\nimport javax.persistence.EntityManager;\nimport javax.persistence.EntityManagerFactory;\nimport javax.persistence.EntityTransaction;\nimport javax.persistence.Persistence;\nimport javax.persistence.Query;\nimport java.util.List;\nimport java.util.Iterator;\npublic class NewMain {\n public static void main(String arg[])\n { \n EntityManagerFactory emf=\n ```\nPersistence.createEntityManagerFactory(\"newprojectjpa2PU\");\nEntityManager em=emf.createEntityManager();\ntry{\n EntityTransaction entr=em.getTransaction();\n entr.begin();\n Query query = (Query) em.createQuery\n (\"SELECT s FROM Supplier s\n LEFT OUTER JOIN Lineitem l WHERE\n s.S_SUPPKEY=l.L_SUPPKEY\", Supplier.class);\n List list1 = query.getResultList();\n Iterator iterator1= list1.iterator();\n if (L.SUPPKEY.IsEmpty());\n {\n System.out.println\n (\"Checking existence of supplier's objects in lineitem class\");\n while(iterator1.hasNext()){ System.out.println\n (\"ITEM \" + query.getInt(\"S_SUPPKEY\") + \" does not exist in LINEITEM \");\n }\n }\n } finally{\n em.close();\n }\n}\n\nAn example of the output:\nrun:\nChecking existence of supplier's objects in lineitem class\nITEM 199 does not exist in LINEITEM\nBUILD SUCCESSFUL (total time: 3 seconds)\n\nFigure 6.6 shows the run-time of application D for different sizes of the Lineitem class. The run-time varied between 2 to 4 seconds.\n6.2. Anti-Join Traversal\n\nFigure 6.6: Execution Time for Application D\n\nRuntime for Application C and D was 1 hour and 2 seconds respectively for the Lineitem class with 400,000 objects. Application D was also more efficient with the database including 1,700,000 objects. The results were released after 3 hours for Application C and after 4 second for Application D.\n\nBy having 1,700,000 objects in the database, Application C took around 3 hours to release the output while Application D was run in 4 seconds. Application D ran faster than Application C with the same size database.\n\nThe run-time for Application C appears to grow exponentially while the run-time of Application D made a linear chart. Therefore, the performance difference between these two applications appears to be growing exponentially from 400,00 to 1,700,000 objects in Lineitem class. As a conclusion, Application D performed more efficiently than Application C. In order to implement an anti-join application for a large database with complex objects, the implementation of Application D is more efficient than Application C.\n6.3 Aggregation\n\nReal examples were run for counting similar objects from a class to test the performance of aggregation queries. Application E is an aggregation application. It is implemented with nested SELECT statements. This application is designed to find the same objects in a class Lineitem and count them.\n\nApplication E:\n* @author ZahraDavar(zd991)\n\n```java\npackage Demo;\nimport java.math.BigDecimal;\nimport javax.persistence.EntityManager;\nimport javax.persistence.EntityManagerFactory;\nimport javax.persistence.EntityTransaction;\nimport javax.persistence.Persistence;\nimport javax.persistence.Query;\nimport java.util.List;\nimport java.util.Iterator;\npublic class NewMain {\npublic static void main(String arg[]){\nEntityManagerFactory emf=\nPersistence.createEntityManagerFactory(\"newprojectjpa2PU\");\nEntityManager em=emf.createEntityManager();\ntry{\nEntityTransaction entr=em.getTransaction();\nentr.begin();\nQuery query1 = em.createQuery\n(\"SELECT a.l_Suppkey FROM Lineitem a\");\nList list1 = query1.getResultList();\nIterator iterator1= list1.iterator();\nwhile(iterator1.hasNext())\n{\n Query query2 = em.createQuery\n (\"SELECT COUNT(*) as total FROM Lineitem b\n```\nApplication E is executed several times with a different sized database. The results of running Application E presented in Figure 6.7. Figure 6.7 shows that the run-time of Application E is 1.5 hours for 400,000 objects and increased to around 6 hours for 1,800,000 objects.\n\n\n\nApplication F, performs the same operation as Application E using `Group by` clause. The `Group by` clause, grouped the results of counting the same objects and transferring them into the client side. This implementation for counting objects,\neliminates the iteration over all of the objects in the class.\n\nApplication F:\n\n* @author zd991\npackage Demo;\n\nimport java.math.BigDecimal;\nimport javax.persistence.EntityManager;\nimport javax.persistence.EntityManagerFactory;\nimport javax.persistence.EntityTransaction;\nimport javax.persistence.Persistence;\nimport javax.persistence.Query;\nimport java.util.List;\nimport java.util.Iterator;\n\npublic class NewMain {\n public static void main(String arg[]){\n EntityManagerFactory emf=\n Persistence.createEntityManagerFactory(\"newprojectlibraryPU\");\n EntityManager em=emf.createEntityManager();\n try{\n EntityTransaction entr=em.getTransaction();\n entr.begin();\n Query query = (Query) em.createQuery\n (\"SELECT l.l_Suppkey, COUNT(l.L_Suppkey) As total\n FROM Lineitem l\n GROUP BY l.l_Suppkey\n ORDER By total\");\n List list1 = query1.getResultList();\n Iterator iterator1= list1.iterator();\n while(iterator1.hasNext())\n {\n System.out.println(\"query.getInt(\"l.L_Suppkey\")\"+ query.getInt(\"total\"));\n }\n }\n}\nThe run-time of Application F varied between 3 and 5 seconds. This is presented in Figure 6.8.\n\n\n\nA comparison between Figure 6.7 and Figure 6.8 shows a considerable performance difference between Application E and Application F.\n\nFor the Lineitem class including 400,000 objects, runtime Application E was 1.5 hours (5400 seconds), whereas for Application F it was 3 seconds. Therefore, Application F was 1800 times faster than Application E for 400,000 objects in the Lineitem class.\n\nApplication E took 6 hours to release the output while Application F completed in 5 seconds when having 1,800,000 objects in the database. Application F\nruns 4320 times faster than Application E when 1,800,000 objects are in the database.\n\nThe run-time results of Application E increased exponentially while the run-time of Application F made changes between 3 to 5 second. Therefore, the performance difference between these two applications is growing exponentially from 400,000 objects in *Lineitem* class to 1,800,000 objects. Thus, the implementation of Application F is much more efficient than Application E. The implementation of Application F is recommended for implementing an *anti-join* application for a large database with complex objects.\n\nThe results show that by reconfiguring object-relational applications, so that fewer objects are transferred to the client side, more data-processing is performed on the server side which improves the performance of the application. The same application is applicable for the rest of the aggregation functions such as Min and Max. Therefore, to count the minimum or maximum total value of similar objects, the implementation of Application F is more efficient than Application E.\n6.4 Analysis of the results\n\nIn all three sets of experiments, the optimised version of the application shows better performance than the original version of the program. To achieve better performance of the application, the implementation of the application is changed, to shift more of the data-processing to the server side and to decrease the amount of data transferring from the server side to the client side.\n\nIn all of the experiments, the number of the objects in Lineitem class varies between 400,000 objects to 1,800,000 objects. Table 6.1 includes all the experimental results for optimise and non-optimise versions of the applications.\n\nIn the Table 6.1, symbol $h$ refers to hour and symbol $s$ refers to seconds. Execution time of the non-optimised versions of join application started from one hour and increased to six hours, while, the execution time of the optimised version of the same application run between two to five seconds.\n\nAs explained in Table 6.1 the run time of the non-optimised version of the anti-join application for 400,000 objects in the Lineitem class is three hours and it increases to 13 hours for 1,800,000 objects in the Lineitem class. The optimised version of the anti-join application run between two to four second.\n\nThe execution time of the aggregation application which is listed in Table 6.1, is similar to the join application. The non-optimise version of the application was running between one to six hours while the optimised version takes only three to five seconds.\n\nThe performance difference between the optimised and non-optimised application is significant in Table 6.1 for both join and aggregation operations. Anti-join application, provides similar results as join since similar algorithms are used for both of them. Antijon is faster than the join application since the data transmission is smaller.\n### Table 6.1: Analysis of Results\n\n<table>\n<thead>\n<tr>\n<th>Number of Objects</th>\n<th>Time Join</th>\n<th>Time Anti-Join</th>\n<th>Time Aggregation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>Non-Opt(h)</td>\n<td>Opt(s)</td>\n<td>Non-Opt(h)</td>\n</tr>\n<tr>\n<td>400,000</td>\n<td>0.90</td>\n<td>2</td>\n<td>3.20</td>\n</tr>\n<tr>\n<td>500,000</td>\n<td>0.94</td>\n<td>2</td>\n<td>3.40</td>\n</tr>\n<tr>\n<td>600,000</td>\n<td>1.60</td>\n<td>3</td>\n<td>3.80</td>\n</tr>\n<tr>\n<td>700,000</td>\n<td>1.50</td>\n<td>2</td>\n<td>4.40</td>\n</tr>\n<tr>\n<td>800,000</td>\n<td>1.70</td>\n<td>2</td>\n<td>5.20</td>\n</tr>\n<tr>\n<td>900,000</td>\n<td>1.80</td>\n<td>3</td>\n<td>5.80</td>\n</tr>\n<tr>\n<td>1,000,000</td>\n<td>1.90</td>\n<td>3</td>\n<td>6.30</td>\n</tr>\n<tr>\n<td>1,100,000</td>\n<td>2.00</td>\n<td>3</td>\n<td>7.40</td>\n</tr>\n<tr>\n<td>1,200,000</td>\n<td>2.05</td>\n<td>4</td>\n<td>8.90</td>\n</tr>\n<tr>\n<td>1,300,000</td>\n<td>2.20</td>\n<td>4</td>\n<td>9.80</td>\n</tr>\n<tr>\n<td>1,400,000</td>\n<td>2.50</td>\n<td>3</td>\n<td>11.20</td>\n</tr>\n<tr>\n<td>1,500,000</td>\n<td>2.60</td>\n<td>4</td>\n<td>12.20</td>\n</tr>\n<tr>\n<td>1,550,000</td>\n<td>3.00</td>\n<td>4</td>\n<td>12.50</td>\n</tr>\n<tr>\n<td>1,600,000</td>\n<td>3.50</td>\n<td>4</td>\n<td>12.80</td>\n</tr>\n<tr>\n<td>1,700,000</td>\n<td>4.30</td>\n<td>4</td>\n<td>13.00</td>\n</tr>\n<tr>\n<td>1,750,000</td>\n<td>5.20</td>\n<td>4</td>\n<td>13.15</td>\n</tr>\n<tr>\n<td>1,800,000</td>\n<td>5.80</td>\n<td>4</td>\n<td>13.25</td>\n</tr>\n</tbody>\n</table>\nChapter 7\n\nConclusion and Future Work\n\n7.1 Conclusion\n\nThis thesis solves the problem of implementing efficient OO applications in the client-server environment. The research also eliminates the performance problem of object-oriented applications within a distributed information system.\n\nIn this regard, some experiments were performed to determine the performance problem of object-relational applications with real applications. Based on the experimental results certain transformation rules, have been proposed to shift more data-processing to the server side. This approach increases the amount of non-procedural code as opposed to procedural code in the body of object-oriented applications. Therefore the amount of data transferred from the client side to the server side. Only the necessary objects which satisfy the condition of the application is transferred from the client side to the server side. The proposed transformation rules, results in high performance relational applications.\n\nThree types of transformation rules are considered and their correctness are proven based on the Floyd Hoare logic. Software patterns of the rules are also presented to make the rules more applicable. The patterns are based on JAVA templates.\n\nThese applications can be improved with the use of new support tool. A support tool can be designed to apply the patterns automatically to the applications. This support tool can be used by application developers. The tool must divide the application into different parts and match each part with one of the patterns to apply the patterns. As a result the final pattern of the application must be created. This tool must apply the transformation rules on the final pattern and as a result the\noptimised version of the application.\n\nNote that the research presented in this thesis focuses on reducing the overall run-time of OO applications in the client-server database environments. This was predominantly achieved by reducing the amount of data that needs to be transmitted and by reducing the client side compute requirement. The proposed approach increases the server side load, though this impact can be neglected in distributed server systems. Since the load can be distributed across servers.\n\n7.2 Future Work\n\nDeveloping a compiler-level optimizer tool for the rules was not in the scope of this thesis and remains for future work and consideration at PhD level. This optimiser tool needs to recognise the right rule for non-optimised code and automatically translates the code into an equivalent but more efficient application. To implement this tool, one or more modern ORM frameworks (Hibernate, Ruby or LINQ) which were presented in Chapter 2 can be used.\nAppendix A\n\nSource code in JPA Format\n\nA.1 Class ’LINEITEM’ Source Code\n\n/*\n * To change this template, choose Tools | Templates\n * and open the template in the editor.\n */\npackage Demo;\n\nimport java.io.Serializable;\nimport java.math.BigDecimal;\nimport java.util.Date;\nimport javax.persistence.*\nimport javax.xml.bind.annotation.XmlRootElement;\n/**\n *\n * @author zd991\n */\n@Entity\n@Table(name = \"LINEITEM\")\n@XmlRootElement\n@NamedQueries({\n @NamedQuery(name = \n \"Lineitem.findAll\", query = \"SELECT l FROM Lineitem l\"),\n @NamedQuery(name = \n \"Lineitem.findByLOrderkey\",\n 90\nquery = \"SELECT l FROM Lineitem l WHERE \n l.lineitemPK.lOrderkey = :lOrderkey\"),\n@NamedQuery(name = \n \"Lineitem.findByLLinenumber\",\nquery = \"SELECT l FROM Lineitem l WHERE \n l.lineitemPK.lLinenumber = :lLinenumber\"),\n@NamedQuery(name = \n \"Lineitem.findByLQuantity\",\nquery = \"SELECT l FROM Lineitem l WHERE \n l.lQuantity = :lQuantity\"),\n@NamedQuery(name = \n \"Lineitem.findByLExtractedprice\",\nquery = \"SELECT l FROM Lineitem l WHERE \n l.lExtendedprice = :lExtendedprice\"),\n@NamedQuery(name = \n \"Lineitem.findByLDiscount\",\nquery = \"SELECT l FROM Lineitem l WHERE \n l.lDiscount = :lDiscount\"),\n@NamedQuery(name = \n \"Lineitem.findByLTax\",\nquery = \"SELECT l FROM Lineitem l WHERE \n l.lTax = :lTax\"),\n@NamedQuery(name = \n \"Lineitem.findByLReturnflag\",\nquery = \"SELECT l FROM Lineitem l WHERE \n l.lReturnflag = :lReturnflag\"),\n@NamedQuery(name = \n \"Lineitem.findByLLinestatus\",\nquery = \"SELECT l FROM Lineitem l WHERE \n l.lLinestatus = :lLinestatus\"),\n@NamedQuery(name = \n \"Lineitem.findByLShipdate\",\nquery = \"SELECT l FROM Lineitem l WHERE \n l.lShipdate = :lShipdate\"),\n@NamedQuery(name = \n \"Lineitem.findByLCommitdate\", \nquery = \"SELECT l FROM Lineitem l WHERE \n l.lCommitdate = :lCommitdate\"),\n```java\npublic class Lineitem implements Serializable {\n private static final long serialVersionUID = 1L;\n\n @EmbeddedId\n protected LineitemPK lineitemPK;\n // @Max(value=?) @Min(value=?)\n @Basic(optional = false)\n @Column(name = \"L_QUANTITY\")\n private BigDecimal lQuantity;\n @Basic(optional = false)\n @Column(name = \"L_EXTENDEDPRICE\")\n private BigDecimal lExtendedprice;\n @Basic(optional = false)\n @Column(name = \"L_DISCOUNT\")\n private BigDecimal lDiscount;\n @Basic(optional = false)\n @Column(name = \"L_TAX\")\n private BigDecimal lTax;\n}\n```\nprivate char lReturnflag;\n\nprivate char lLinestatus;\n\nprivate Date lShipdate;\n\nprivate Date lCommitdate;\n\nprivate Date lReceiptdate;\n\nprivate String lShipinstruct;\n\nprivate String lShipmode;\n\nprivate String lComment;\n\n@JoinColumns({\n @JoinColumn\n (name = \"L_PARTKEY\", referencedColumnName = \"PS_PARTKEY\"),\n @JoinColumn\n (name = \"L_SUPPKEY\", referencedColumnName = \"PS_SUPPKEY\")})\n\n@ManyToOne(optional = false)\nprivate Partsupp partsupp;\n\n@JoinColumn\n(name = \"L_ORDERKEY\",\nreferencedColumnName = \"O_ORDERKEY\",}\ninsertable = false, updatable = false)\n@ManyToOne(optional = false)\nprivate Orders orders;\n\npublic Lineitem() {\n}\n\npublic Lineitem(LineitemPK lineitemPK) {\n this.lineitemPK = lineitemPK;\n}\n\npublic Lineitem(LineitemPK lineitemPK,\n BigDecimal lQuantity, BigDecimal lExtendedprice,\n BigDecimal lDiscount, BigDecimal lTax,\n char lReturnflag, char lLinestatus,\n Date lShipdate, Date lCommitdate,\n Date lReceiptdate, String lShipinstruct,\n String lShipmode, String lComment) {\n this.lineitemPK = lineitemPK;\n this.lQuantity = lQuantity;\n this.lExtendedprice = lExtendedprice;\n this.lDiscount = lDiscount;\n this.lTax = lTax;\n this.lReturnflag = lReturnflag;\n this.lLinestatus = lLinestatus;\n this.lShipdate = lShipdate;\n this.lCommitdate = lCommitdate;\n this.lReceiptdate = lReceiptdate;\n this.lShipinstruct = lShipinstruct;\n this.lShipmode = lShipmode;\n this.lComment = lComment;\n}\n\npublic Lineitem(long lOrderkey, long lLinenumber) {\n this.lineitemPK =\n new LineitemPK(lOrderkey, lLinenumber);\n}\npublic LineitemPK getLineitemPK() {\n return lineitemPK;\n}\n\npublic void setLineitemPK(LineitemPK lineitemPK) {\n this.lineitemPK = lineitemPK;\n}\n\npublic BigDecimal getLQuantity() {\n return lQuantity;\n}\n\npublic void setLQuantity(BigDecimal lQuantity) {\n this.lQuantity = lQuantity;\n}\n\npublic BigDecimal getLExtendedprice() {\n return lExtendedprice;\n}\n\npublic void setLExtendedprice(BigDecimal lExtendedprice) {\n this.lExtendedprice = lExtendedprice;\n}\n\npublic BigDecimal getLDiscount() {\n return lDiscount;\n}\n\npublic void setLDiscount(BigDecimal lDiscount) {\n this.lDiscount = lDiscount;\n}\n\npublic BigDecimal getLTax() {\n return lTax;\n}\npublic void setLTax(BigDecimal lTax) {\n this.lTax = lTax;\n}\n\npublic char getLReturnflag() {\n return lReturnflag;\n}\n\npublic void setLReturnflag(char lReturnflag) {\n this.lReturnflag = lReturnflag;\n}\n\npublic char getLLinestatus() {\n return lLinestatus;\n}\n\npublic void setLLinestatus(char lLinestatus) {\n this.lLinestatus = lLinestatus;\n}\n\npublic Date getLShipdate() {\n return lShipdate;\n}\n\npublic void setLShipdate(Date lShipdate) {\n this.lShipdate = lShipdate;\n}\n\npublic Date getLCommitdate() {\n return lCommitdate;\n}\n\npublic void setLCommitdate(Date lCommitdate) {\n this.lCommitdate = lCommitdate;\n}\npublic Date getLReceiptdate() {\n return lReceiptdate;\n}\n\npublic void setLReceiptdate(Date lReceiptdate) {\n this.lReceiptdate = lReceiptdate;\n}\n\npublic String getLShipinstruct() {\n return lShipinstruct;\n}\n\npublic void setLShipinstruct(String lShipinstruct) {\n this.lShipinstruct = lShipinstruct;\n}\n\npublic String getLShipmode() {\n return lShipmode;\n}\n\npublic void setLShipmode(String lShipmode) {\n this.lShipmode = lShipmode;\n}\n\npublic String getLComment() {\n return lComment;\n}\n\npublic void setLComment(String lComment) {\n this.lComment = lComment;\n}\n\npublic Partsupp getPartsupp() {\n return partsupp;\n}\n\npublic void setPartsupp(Partsupp partsupp) {\nthis.partsupp = partsupp;\n}\n\npublic Orders getOrders() {\n return orders;\n}\n\npublic void setOrders(Orders orders) {\n this.orders = orders;\n}\n\n@Override\npublic int hashCode() {\n int hash = 0;\n hash += (lineitemPK != null ? lineitemPK.hashCode() : 0);\n return hash;\n}\n\n@Override\npublic boolean equals(Object object) {\n if (!(object instanceof Lineitem)) {\n return false;\n }\n Lineitem other = (Lineitem) object;\n if (((this.lineitemPK == null && other.lineitemPK != null) \n || (this.lineitemPK != null &&\n !this.lineitemPK.equals(other.lineitemPK))) {\n return false;\n }\n return true;\n}\n\n@Override\npublic String toString() {\n return \"Demo.Lineitem[ lineitemPK=\" + lineitemPK + \" ]\";\n}\nA.2 Class ’SUPPLIER’ Source Code\n\n/*\n * To change this template, choose Tools | Templates\n * and open the template in the editor.\n */\npackage Demo;\n\nimport java.io.Serializable;\nimport java.math.BigDecimal;\nimport java.util.Collection;\nimport javax.persistence.*;\nimport javax.xml.bind.annotation.XmlRootElement;\nimport javax.xml.bind.annotation.XmlTransient;\n\n/**\n * @author zd991\n */\n@Entity\n@Table(name = \"SUPPLIER\")\n@XmlRootElement\n@NamedQueries({\n @NamedQuery(name = \"Supplier.findAll\",\n query = \"SELECT s FROM Supplier s\"),\n @NamedQuery(name = \"Supplier.findBySSuppkey\",\n query = \"SELECT s FROM Supplier s WHERE s.sSuppkey = :sSuppkey\"),\n @NamedQuery(name = \"Supplier.findBySName\",\n query = \"SELECT s FROM Supplier s WHERE s.sName = :sName\"),\n @NamedQuery(name = \"Supplier.findBySAddress\",\n query = \"SELECT s FROM Supplier s WHERE s.sAddress = :sAddress\"),\n @NamedQuery(name = \"Supplier.findBySPhone\",\n query = \"SELECT s FROM Supplier s WHERE s.sPhone = :sPhone\"),\n @NamedQuery(name = \"Supplier.findBySAcctbal\",\n query = \"SELECT s FROM Supplier s WHERE s.sAcctbal = :sAcctbal\"),\n})\n}\nA.2. Class 'SUPPLIER' Source Code\n\n```java\npublic class Supplier implements Serializable {\n private static final long serialVersionUID = 1L;\n @Id\n @Basic(optional = false)\n @Column(name = \"S_SUPPKEY\")\n private Long sSuppkey;\n @Basic(optional = false)\n @Column(name = \"S_NAME\")\n private String sName;\n @Basic(optional = false)\n @Column(name = \"S_ADDRESS\")\n private String sAddress;\n @Basic(optional = false)\n @Column(name = \"S_PHONE\")\n private String sPhone;\n @JoinColumn(name = \"S_NATIONKEY\",\n referencedColumnName = \"N_NATIONKEY\")\n @ManyToOne(optional = false)\n private Nation sNationkey;\n @OneToMany(cascade = CascadeType.ALL, mappedBy = \"supplier\")\n private Collection<Partsupp> partsuppCollection;\n\n public Supplier() {\n }\n\n public Supplier(Long sSuppkey) {\n this.sSuppkey = sSuppkey;\n }\n}\n```\n\npublic Supplier(Long sSuppkey, String sName,\nString sAddress, String sPhone,\nBigDecimal sAcctbal, String sComment) {\n this.sSuppkey = sSuppkey;\n this.sName = sName;\n this.sAddress = sAddress;\n this.sPhone = sPhone;\n this.sAcctbal = sAcctbal;\n this.sComment = sComment;\n}\n\npublic Long getSSuppkey() {\n return sSuppkey;\n}\n\npublic void setSSuppkey(Long sSuppkey) {\n this.sSuppkey = sSuppkey;\n}\n\npublic String getSName() {\n return sName;\n}\n\npublic void setSName(String sName) {\n this.sName = sName;\n}\n\npublic String getSAddress() {\n return sAddress;\n}\n\npublic void setSAddress(String sAddress) {\n this.sAddress = sAddress;\n}\npublic String getSPhone() {\n return sPhone;\n}\n\npublic void setSPhone(String sPhone) {\n this.sPhone = sPhone;\n}\n\npublic BigDecimal getSAcctbal() {\n return sAcctbal;\n}\n\npublic void setSAcctbal(BigDecimal sAcctbal) {\n this.sAcctbal = sAcctbal;\n}\n\npublic String getSComment() {\n return sComment;\n}\n\npublic void setSComment(String sComment) {\n this.sComment = sComment;\n}\n\npublic Nation getSNationkey() {\n return sNationkey;\n}\n\npublic void setSNationkey(Nation sNationkey) {\n this.sNationkey = sNationkey;\n}\n\n@XmlTransient\npublic Collection<Partsupp> getPartsuppCollection() {\n return partsuppCollection;\n}\npublic void setPartsuppCollection(\nCollection<Partsupp> partsuppCollection) {\n this.partsuppCollection = partsuppCollection;\n}\n\n@Override\npublic int hashCode() {\n int hash = 0;\n hash += (sSuppkey != null ? sSuppkey.hashCode() : 0);\n return hash;\n}\n\n@Override\npublic boolean equals(Object object) {\n if (!(object instanceof Supplier)) {\n return false;\n }\n Supplier other = (Supplier) object;\n if ((this.sSuppkey ==\n null & other.sSuppkey != null)\n || (this.sSuppkey != null\n && !this.sSuppkey.equals(other.sSuppkey))) {\n return false;\n }\n return true;\n}\n\n@Override\npublic String toString() {\n return \"Demo.Supplier[ sSuppkey=\" + sSuppkey + \" ]\";\n}\n\n}\n<persistence version=\"2.0\"\nxmlns=\"http://java.sun.com/xml/ns/persistence\"\nxmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\nxsi:schemaLocation=\"http://java.sun.com/xml/ns/persistence\nhttp://java.sun.com/xml/ns/persistence/persistence_2_0.xsd\">\n <persistence-unit name=\"newprojectjpa2PU\"\n transaction-type=\"RESOURCE_LOCAL\">\n <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>\n <class>Demo.Part</class>\n <class>Demo.Orders</class>\n <class>Demo.Supplier</class>\n <class>Demo.Lineitem</class>\n <class>Demo.Region</class>\n <class>Demo.Partsupp</class>\n <class>Demo.Nation</class>\n <class>Demo.Customer</class>\n <properties>\n <property name=\"eclipselink.id-validation\"\n value=\"NULL\"/>\n <property name=\"javax.persistence.jdbc.url\"\n <property name=\"javax.persistence.jdbc.password\"\n value=\"*******\"/>\n <property name=\"javax.persistence.jdbc.driver\"\n value=\"oracle.jdbc.OracleDriver\"/>\n <property name=\"javax.persistence.jdbc.user\"\n value=\"csci315\"/>\n </properties>\n </persistence-unit>\n</persistence>\nBibliography\n\n\n[Jac14] Jeff Jacobs. Identifying and refactoring common sql performance anti-patterns. pages 1–9, Northen California, USA, Aug 2014. LLC.\n\n\n"}}},{"rowIdx":63,"cells":{"id":{"kind":"string","value":"3088fd2a179ac20aef0ec717bc04ea7fd56dcf98"},"text":{"kind":"string","value":"# Table of Contents\n\nPreface .................................................................................................................. 1\n Naming ................................................................................................................. 1\n Hazelcast IMDG ................................................................................................. 1\n Licensing ............................................................................................................. 1\n Trademarks ......................................................................................................... 1\n Getting Help ....................................................................................................... 1\n Release Notes ..................................................................................................... 2\n\n1. Browser Compatibility ....................................................................................... 2\n\n2. Getting Started .................................................................................................. 2\n 2.1. Downloading Management Center ............................................................... 2\n 2.2. Starting the Management Center Service .................................................... 2\n 2.2.1. Using the Command Line ................................................................... 3\n 2.2.2. Deploying to Application Server ......................................................... 3\n 2.2.3. Using Scripts in the Package ............................................................... 3\n 2.3. Quick Launch ............................................................................................... 4\n\n3. Configuring Management Center ...................................................................... 5\n 3.1. Providing a License .................................................................................... 5\n 3.2. Providing an Extra Classpath ...................................................................... 5\n 3.3. Configuring the Client Used by Management Center .................................... 6\n 3.4. Configuring Disk Usage ............................................................................. 6\n 3.5. Enabling Health Check Endpoint .................................................................. 7\n 3.6. Configuring Sessions .................................................................................. 7\n 3.6.1. Configuring Session Timeout ................................................................ 8\n 3.6.2. Disabling Multiple Simultaneous Login Attempts .................................. 8\n 3.6.3. Disable Login Configuration ............................................................... 8\n 3.6.4. Forcing Logout on Multiple Simultaneous Login Attempts .................... 9\n 3.7. Configuring and Enabling Security ............................................................. 9\n 3.7.1. Using Management Center with TLS/SSL Only ..................................... 9\n 3.7.2. Enabling TLS/SSL When Starting with WAR File ................................. 10\n Enabling HTTP Port .................................................................................. 11\n Managing TLS Enabled Clusters .............................................................. 11\n 3.7.3. Mutual Authentication ........................................................................ 12\n Managing Mutual Authentication Enabled Clusters ................................... 12\n Excluding Specific TLS/SSL Protocols ..................................................... 13\n 3.7.4. Using a Dictionary to Prevent Weak Passwords ...................................... 13\n 3.8. Configuring Logging ................................................................................... 13\n 3.8.1. Enabling Audit Logging ....................................................................... 16\n 3.9. Using Variable Replacers .......................................................................... 18\n19.6.3. Retrieve Operation Service Information .................................................. 103\n19.6.4. Retrieve Event Service Information .......................................................... 103\n19.6.5. Retrieve Partition Service Information .................................................... 104\n19.6.6. Retrieve Proxy Service Information ......................................................... 104\n19.6.7. Retrieve All Managed Executors ............................................................... 105\n19.6.8. Retrieve a Managed Executor ................................................................. 105\n19.7. Client Endpoints Resource ........................................................................... 105\n 19.7.1. Retrieve List of Client Endpoints ............................................................ 106\n 19.7.2. Retrieve Client Endpoint Information .................................................. 106\n19.8. Maps Resource .............................................................................................. 106\n 19.8.1. Retrieve List of Maps ............................................................................. 107\n 19.8.2. Retrieve Map Information ................................................................... 107\n19.9. MultiMaps Resource ..................................................................................... 108\n 19.9.1. Retrieve List of MultiMaps .................................................................... 108\n 19.9.2. Retrieve MultiMap Information ............................................................. 109\n19.10. ReplicatedMaps Resource ......................................................................... 109\n 19.10.1. Retrieve List of ReplicatedMaps .......................................................... 109\n 19.10.2. Retrieve ReplicatedMap Information ................................................... 110\n19.11. Queues Resource ......................................................................................... 111\n 19.11.1. Retrieve List of Queues ...................................................................... 111\n 19.11.2. Retrieve Queue Information ................................................................ 111\n19.12. Topics Resource .......................................................................................... 112\n 19.12.1. Retrieve List of Topics ...................................................................... 112\n 19.12.2. Retrieve Topic Information ................................................................ 112\n19.13. Executors Resource .................................................................................... 113\n 19.13.1. Retrieve List of Executors .................................................................. 113\n 19.13.2. Retrieve Executor Information [GET] ................................................... 113\n [/rest/clusters/{clusternname}/executors/{executorName}]\n 19.14.1. Retrieve List of Client UUIDs ................................................................. 114\n [/rest/clusters/{clusternname}/clientStats/{clientUuid}]\n [/rest/clusters/{clusternname}/wanStats/{wanReplication}/publishers/{publisher}]\n20. Clustered JMX ................................................................................................. 117\n 20.1. Configuring Clustered JMX ......................................................................... 117\n 20.1.1. Enabling TLS/SSL for Clustered JMX ................................................... 118\n Additional TLS/SSL Configuration Options .................................................... 119\n 20.2. Clustered JMX API ...................................................................................... 119\n 20.3. Integrating with New Relic ........................................................................ 128\n 20.4. Integrating with AppDynamics .................................................................... 129\nWelcome to the Reference Manual of Hazelcast IMDG Management Center. This manual includes concepts and instructions to guide you on how to use Management Center to monitor your Hazelcast IMDG Cluster.\n\nPreface\n\nHazelcast Management Center enables you to monitor and manage your cluster members running Hazelcast IMDG. In addition to monitoring the overall state of your clusters, you can also analyze and browse your data structures in detail, update map configurations and take thread dumps from the members. You can run scripts (JavaScript, Groovy, etc.) and commands on your members with its scripting and console modules.\n\nNaming\n\n- **Hazelcast Management Center** or **Management Center** refers to the Hazelcast IMDG cluster monitoring tool provided by Hazelcast, Inc.\n- **Hazelcast IMDG** or just **Hazelcast** refers to the Hazelcast in-memory data grid middleware. **Hazelcast** is also the name of the company (Hazelcast, Inc.) providing Hazelcast IMDG.\n\nHazelcast IMDG\n\nHazelcast Management Center is delivered with Hazelcast IMDG. It can also be downloaded as a separate package from the hazelcast.org website.\n\nSee the **Hazelcast IMDG Reference Manual** for all Hazelcast IMDG topics including the clusters and their operations, clients, data structures, computing and WAN replication.\n\nLicensing\n\nHazelcast Management Center and this Reference Manual are free and provided under the Apache License, Version 2.0.\n\nTrademarks\n\nHazelcast is a registered trademark of Hazelcast, Inc. All other trademarks in this manual are held by their respective owners.\n\nGetting Help\n\nSupport is provided via the following channels:\n\n- **Troubleshooting** section of this guide\n- **Stack Overflow** (ask a question on how to use Management Center properly and troubleshoot your setup)\n• Hazelcast mailing list (propose features and discuss your ideas with the team)\n\nRelease Notes\n\nSee the Release Notes document for the new features, enhancements and fixes performed for each Hazelcast Management Center release.\n\n1. Browser Compatibility\n\nThe Hazelcast Management Center is tested and works on the following browsers:\n\n• Last two versions of Chrome at the time of release\n• Last two versions of Firefox at the time of release\n• Latest Safari\n• Internet Explorer 11\n• Latest Microsoft Edge\n\n2. Getting Started\n\nTo start using the Management Center:\n\n1. download the Hazelcast IMDG or Management Center package\n2. start the Management Center service\n3. launch the Management Center user interface.\n\n2.1. Downloading Management Center\n\nHazelcast Management Center is included in the Hazelcast IMDG download package. You can download it from the download page of Hazelcast’s website.\n\nWhen a new Hazelcast IMDG version is released, it comes with a Management Center that is compatible with IMDG. There may be times when a new Management Center version is released before a new version of Hazelcast IMDG. In that case, you may download the new Management Center from its download page as a separate package.\n\n2.2. Starting the Management Center Service\n\nYou have the following options to start the Management Center service:\n\n• starting Hazelcast Management Center from the command line\n• using the scripts that come with the download package.\n• deploying the file hazelcast-management-center-4.0.2.war on your Java application server/container\nYou need Java Runtime Environment 1.8 or later to run Hazelcast Management Center.\n\n### 2.2.1. Using the Command Line\n\nAfter you downloaded, extract the Hazelcast IMDG or Management Center package. The extracted directory, i.e., `hazelcast-management-center-4.0.2`, contains the `hazelcast-management-center-4.0.2.war` file.\n\nYou can start this file directly from the command line using the following command:\n\n```java\njava -jar hazelcast-management-center-4.0.2.war\n```\n\nThe above command starts the Hazelcast Management Center service on the port 8080 with the root context path (`http://localhost:8080`).\n\nIn Management Center 4.0, the default context path changed from `hazelcast-mancenter` to the root context path.\n\nYou can use `-Dhazelcast.mc.http.port` and `-Dhazelcast.mc.contextPath` command line options to start Management Center on a different port and context path:\n\n```java\njava -Dhazelcast.mc.http.port=8083 -Dhazelcast.mc.contextPath='hazelcast-mc' -jar hazelcast-management-center-4.0.2.war\n```\n\nThe above command starts Management Center on port 8083 and context path `hazelcast-mc`. You can access it by opening `http://localhost:8083/hazelcast-mc` in your browser.\n\nThen, you need to let Management Center know the Hazelcast IMDG member addresses as explained in the Connecting IMDG Members to Management Center chapter.\n\nFor the options you can provide when starting with the command line, see the Configuring Management Center chapter. In that chapter, you can learn about topics including how to start with a license or extra classpath, how to configure the security, disk usage, update interval or logging.\n\n### 2.2.2. Deploying to Application Server\n\nInstead of starting at the command line, you can deploy the Management Center to your application server (Tomcat, Jetty, etc.).\n\n### 2.2.3. Using Scripts in the Package\n\nAs another option, you can use the `start.bat` or `start.sh` scripts, which come with the download package, to start the Management Center. You can find these scripts under the extracted directory.\n2.3. Quick Launch\n\nAfter the above steps are completed, let’s quickly open the Management Center user interface with the default settings.\n\nAssuming that you have started your Hazelcast IMDG cluster with a single member on your local machine and the Management Center service on http://localhost:8080, follow the below instructions:\n\n2. Create your credentials in the \"Configure Security\" dialog:\n a. Select Default as the security provider.\n b. Create your username and password.\n c. Click on the Save button.\n3. Login with your newly created credentials, and \"Manage Clusters\" page appears.\n4. Click on the \"Add Cluster Config\" button to connect Management Center to your cluster.\n5. Click on the Save button with the default values (dev and localhost) on the \"Add Cluster Config\" page.\n6. Click on the Select button on the \"Manage Clusters\" page and the dashboard of your cluster appears as shown below.\n\nSee Launching the Management Center User Interface chapter for more details.\n\nAlso see here in the Hazelcast IMDG Reference Manual for information on starting a Hazelcast member.\n3. Configuring Management Center\n\nThis chapter explains how you can configure the Management Center according to your needs.\n\nThe way Management Center connects and communicates with IMDG clusters has been redesigned in Management Center 4.0.\n\nFrom Management Center 4.0 and onwards, the communications between the IMDG cluster members and the Management Center instance are based on the IMDG client protocol. The IMDG clusters that Management Center should connect to are now configured within Management Center as described in Connecting Management Center to IMDG Members.\n\nIn previous versions, the URL of the Management Center instance was configured within the `<hazelcast></hazelcast>` section of `hazelcast.xml` for each member of the IMDG cluster. This configuration is now depreciated and ignored.\n\n3.1. Providing a License\n\nWhen starting the Management Center from the command line, a license can be provided using the system property `hazelcast.mc.license`. For example by using the command line parameter:\n\n```\njava -Dhazelcast.mc.license=<key> -jar hazelcast-management-center-4.0.2.war\n```\n\nWhen this option is used, the license provided takes precedence over any license set and stored previously using the user interface. Previously stored licenses are not affected and will be used again when the Management Center is started without the `hazelcast.mc.license` property. This also means no new license can be stored when the property is used.\n\n3.2. Providing an Extra Classpath\n\nYou can also start the Management Center with an extra classpath entry (for example, when using JAAS authentication) by using the following command:\n\n```\njava -cp \"hazelcast-management-center-4.0.2.war:/path/to/an/extra.jar\" com.hazelcast.webmonitor.Launcher\n```\n\nOn Windows, the command becomes as follows (semicolon instead of colon):\n\n```\njava -cp \"hazelcast-management-center-4.0.2.war;/path/to/an/extra.jar\" com.hazelcast.webmonitor.Launcher\n```\n3.3. Configuring the Client Used by Management Center\n\nYou can configure the client instance that is used for connecting to the cluster by using the following command line parameters:\n\n- `-Dhazelcast.mc.client.initial.backoff.millis`: Duration, in milliseconds, to wait after the first failure before retrying. It is in milliseconds. The default value is 1000 ms. Set values have to be in range of 1000 to 60000 ms.\n\n- `-Dhazelcast.mc.client.backoff.multiplier`: Factor with which to multiply backoff after a failed retry. Default value is 2. Set values have to be in range of 1 to 10.\n\n- `-Dhazelcast.mc.client.max.backoff.millis`: When backoff reaches this upper bound, it does not increase any more. It is in milliseconds. Default value is 32000 ms. Set values have to be in range of 32000 to 600000 ms.\n\nNote that these parameters apply to all clients that are started by Management Center.\n\nYou can also pass in a custom client configuration file to Management Center. These parameters override any configuration you pass as part of adding a new cluster connection. Following is a list of all other client configuration parameters that are overridden by Management Center when creating clients to connect to clusters:\n\n- **InstanceName**: Generated based on the cluster name.\n\n- **ConnectionStrategyConfig.asyncStart**: Set to `true`. It means that the client starts without waiting to get a cluster connection.\n\n- **ConnectionStrategyConfig.clusterConnectTimeoutMillis**: Set to infinity. The client never gives up trying to connect to the cluster.\n\n- **NetworkConfig.smartRouting**: Set to `true`. It means that client will open connections to all members.\n\n3.4. Configuring Disk Usage\n\nThe disk space used by the Management Center is constrained to avoid exceeding available disk space. When the set limit is exceeded, the Management Center deals with this in the following ways:\n\n- Persisted statistics data is removed, starting with the oldest (one month at a time).\n\nUsually, either of the above automatically resolves the situation and makes room for new data. Depending on the disk usage configuration and the kind of data that contributes to exceeding the limit it can occur that the limit continues to be exceeded. In this case, the Management Center does not store new metrics data. Other data (like configurations and account information) is still stored as they hardly cause larger data volumes.\n\nAn active blockage is reported in the UI as an error notification, as shown below:\nHowever, storage operations do not explicitly fail or report errors since this would constantly cause interruptions and error logging both in the UI and logs.\n\nOne way to resolve a blockage is to restart the Management Center with a higher limit or in the purge mode (if not used before).\n\nYou can use the following system properties to configure the Management Center’s disk usage control:\n\n- `-Dhazelcast.mc.disk.usage.mode`: Available values are purge and block. If the mode is purge, persisted statistics data is removed (as stated in the beginning of this section). If it is block, persisted statistics data is not removed. Its default value is purge.\n\n- `-Dhazelcast.mc.disk.usage.limit`: The high water mark in KB, MB or GB. Its default value adapts to the available disk space and the space already used by database files. At a maximum it will default to 512MB unless existing data already exceeds this maximum. In that case the already used space is used as limit. The minimal allowed limit is 2MB.\n\n- `-Dhazelcast.mc.disk.usage.interval`: Specifies how often the disk usage is checked to see if it exceeds the limit (hazelcast.mc.disk.usage.limit). It is in milliseconds and its default value is 1000 milliseconds. Set values have to be in range of 50 to 5000 ms.\n\nIt is important to understand that the limit given is a soft limit, a high water mark. The Management Center will act if it is exceeded but it might be exceeded by a margin between two measurements. Do not set it to the absolute maximum disk space available. A smaller interval increases accuracy but also performance overhead.\n\nIn case of a misconfiguration of any of the above three properties, the Management Center logs the problem and aborts startup immediately.\n\n### 3.5. Enabling Health Check Endpoint\n\nWhen running the Management Center from the command line, you can enable the Health Check endpoint. This endpoint responds with 200 OK HTTP status code once the Management Center web application has started. The endpoint is available on port `<Management Center HTTP port> + 1` with context path `<Management Center context path>/health` (by default, its URL is http://localhost:8081/health). Note that the HTTP protocol is always used for the Health Check endpoint, independently of TLS/SSL settings, and no additional authentication is enforced for it.\n\nIf you want to enable the Health Check endpoint, use the following command line argument:\n\n```\n-Dhazelcast.mc.healthCheck.enable=true\n```\n\n### 3.6. Configuring Sessions\n\nThis section provides information on how to configure the Management Center sessions for various aspects including timeouts and login/logout operations.\n3.6.1. Configuring Session Timeout\n\nIf you have started the Management Center from the command line by using the WAR file, by default, the sessions that are inactive for 30 minutes are invalidated. To change this, you can use the `-Dhazelcast.mc.session.timeout.seconds` command line parameter.\n\nFor example, the following command starts the Management Center with a session timeout period of 1 minute:\n\n```\njava -Dhazelcast.mc.session.timeout.seconds=60 -jar hazelcast-management-center-4.0.2.war\n```\n\nIf you have deployed the Management Center on an application server/container, you can configure the default session timeout period of the application server/container to change the session timeout period for the Management Center. If your server/container allows application specific configuration, you can use it to configure the session timeout period for the Management Center.\n\n3.6.2. Disabling Multiple Simultaneous Login Attempts\n\nNormally, a user account on the Management Center can be used from multiple locations at the same time. If you want to forbid others from logging in, when there’s already someone logged in with the same username, you can start the Management Center with the `-Dhazelcast.mc.allowMultipleLogin=false` command line parameter.\n\n3.6.3. Disable Login Configuration\n\nIn order to prevent password guessing attacks, logging in is disabled temporarily after a number of failed login attempts. When not configured explicitly, the default values are used, i.e., logging in is disabled for 5 seconds when a username is failed to log in consecutively 3 times. During this 5 seconds of period, logging in is not allowed even when the correct credentials are used. After 5 seconds, the user will be able to log in using the correct credentials.\n\nAssuming the configuration with the default values, if the failed attempts continue (consecutively 3 times) after the period of disabled login passes, this time the disable period is multiplied by 10: logging in is disabled for 50 seconds. The whole process repeats itself until the user logs in successfully. By default, there’s no upper limit to the disable period, but can be configured by using the `-Dhazelcast.mc.maxDisableLoginPeriod` parameter.\n\nHere is a scenario, in the given order, with the default values:\n\n1. You try to login with your credentials consecutively 3 times but failed.\n2. Logging in is disabled and you have to wait for 5 seconds.\n3. After 5 seconds have passed, logging in is enabled.\n4. You try to login with your credentials consecutively 3 times but again failed.\n5. Logging in is disabled again and this time you have to wait for 50 seconds until your next login attempt.\n6. And so on; each 3 consecutive login failures causes the disable period to be multiplied by 10.\n\nYou can configure the number of failed login attempts, initial and maximum duration of the disabled login and the multiplier using the following command line parameters:\n\n- `-Dhazelcast.mc.failedAttemptsBeforeDisableLogin`: Number of failed login attempts that cause the logging in to be disabled temporarily. Default value is 3.\n\n- `-Dhazelcast.mc.initialDisableLoginPeriod`: Initial duration for the disabled login in seconds. Default value is 5.\n\n- `-Dhazelcast.mc.disableLoginPeriodMultiplier`: Multiplier used for extending the disable period in case the failed login attempts continue after disable period passes. Default value is 10.\n\n- `-Dhazelcast.mc.maxDisableLoginPeriod`: Maximum amount of time for the disable login period. This parameter does not have a default value. By default, disabled login period is not limited.\n\n### 3.6.4. Forcing Logout on Multiple Simultaneous Login Attempts\n\nIf you haven’t allowed multiple simultaneous login attempts explicitly, the first user to login with a username stays logged in until that username explicitly logs out or its session expires. In the meantime, no one else can login with the same username. If you want to force logout for the first user and let the newcomer login, you need to start Management Center with the `-Dhazelcast.mcFORCELogoutOnMultipleLogin=true` command line parameter.\n\n### 3.7. Configuring and Enabling Security\n\nThis section provides information on how to use and manage the Management Center with TLS/SSL and mutual authentication. You will also learn how to force the users to specify passwords that are hard to guess.\n\n#### 3.7.1. Using Management Center with TLS/SSL Only\n\nTo encrypt data transmitted over all channels of the Management Center using TLS/SSL, make sure you do all of the following:\n\n- Deploy the Management Center on a TLS/SSL enabled container or start it from the command line with TLS/SSL enabled. See [Installing the Management Center](#).\n - Another option is to place the Management Center behind a TLS-enabled reverse proxy. In that case, make sure your reverse proxy sets the necessary HTTP header (`X-Forwarded-Proto`) for resolving the correct protocol.\n\n- Enable TLS/SSL communication to the Management Center for your Hazelcast cluster. See [Connecting Hazelcast members to the Management Center](#).\n\n- If you’re using Clustered JMX on the Management center, enable TLS/SSL for it. See [Enabling TLS/SSL for Clustered JMX](#).\n\n- If you’re using LDAP authentication, make sure you use LDAPS or enable the \"Start TLS\" field. See [LDAP Authentication](#).\n3.7.2. Enabling TLS/SSL When Starting with WAR File\n\nWhen you start the Management Center from the command line, it serves the pages unencrypted by using \"http\", by default. To enable TLS/SSL, use the following command line parameters when starting the Management Center:\n\n- `Dhazelcast.mc.tls.enabled`: Specifies whether TLS/SSL is enabled. Its default value is false (disabled).\n- `Dhazelcast.mc.tls.keyStore`: Path to the keystore.\n- `Dhazelcast.mc.tls.keyStorePassword`: Password of the keystore.\n- `Dhazelcast.mc.tls.trustStore`: Path to the truststore.\n- `Dhazelcast.mc.tls.trustStorePassword`: Password of the truststore.\n\nYou can leave the truststore and truststore password values empty to use the system JVM’s own truststore.\n\nThe following is an example on how to start the Management Center with TLS/SSL enabled from the command line:\n\n```\njava -Dhazelcast.mc.tls.enabled=true\n -Dhazelcast.mc.tls.keyStore=/some/dir/selfsigned.jks\n -Dhazelcast.mc.tls.keyStorePassword=yourpassword -jar hazelcast-management-center-4.0.2.war\n```\n\nYou can access the Management Center from the following HTTPS URL on port 8443: `https://localhost:8443`.\n\nOn the member side, you need to configure the Management Center URL as `https://localhost:8443` and also set the following JVM arguments when starting the member:\n\n```\n-Djavax.net.ssl.trustStore=path to your truststore\n-Djavax.net.ssl.trustStorePassword=yourpassword\n```\n\nIf you plan to use a self-signed certificate, make sure to create a certificate with the hostname of the machine you will deploy the Management Center on. Otherwise, you will see a line similar to the following in the member logs:\n\n```\njavax.net.ssl.SSLHandshakeException: java.security.cert.CertificateException: No subject alternative names matching IP address 127.0.0.1 found\n```\n\nTo override the HTTPS port, you can use the `-Dhazelcast.mc.https.port` command line option when starting the Management Center. For example:\nThis starts the Management Center on HTTPS port 443.\n\nYou can encrypt the keystore/truststore passwords and pass them as command line arguments in encrypted form for improved security. See the Variable Replacers section for more information.\n\nEnabling HTTP Port\n\nBy default, HTTP port is disabled when you enable TLS. If you want to have an open HTTP port that redirects to the HTTPS port, use the following command line argument:\n\n-Dhazelcast.mc.tls.enableHttpPort=true\n\nManaging TLS Enabled Clusters\n\nIf a Hazelcast cluster is configured to use TLS for communication between its members using a self-signed certificate, the Management Center will not be able to perform some of the operations that use the cluster's HTTP endpoints (such as shutting down a member or getting the thread dump of a member). This is so because self-signed certificates are not trusted by default by the JVM. For these operations to work, you need to configure a truststore containing the public key of the self-signed certificate when starting the JVM of the Management Center using the following command line parameters:\n\n- -Dhazelcast.mc.httpClient.tls.trustStore: Path to the truststore.\n- -Dhazelcast.mc.httpClient.tls.trustStorePassword: Password of the truststore.\n- -Dhazelcast.mc.httpClient.tls.trustStoreType: Type of the truststore. Its default value is JKS.\n- -Dhazelcast.mc.httpClient.tls.trustManagerAlgorithm: Name of the algorithm based on which the authentication keys are provided. System default is used if none is provided. You can find out the default by calling the javax.net.ssl.TrustManagerFactory#getDefaultAlgorithm method.\n\nYou can encrypt the truststore password and pass it as a command line argument in encrypted form for improved security. See the Variable Replacers section for more information.\n\nBy default, JVM also checks for the validity of the hostname of the certificate. If this test fails, you will see a line similar to the following in the Management Center logs:\njavax.net.ssl.SSLHandshakeException: java.security.cert.CertificateException: \nNo subject alternative names matching IP address 127.0.0.1 found\n\nIf you want to disable this check, start the Management Center with the following command line parameter:\n\n-Dhazelcast.mc.disableHostnameVerification=true\n\n3.7.3. Mutual Authentication\n\nYou can configure Management Center to require mutual authentication. With this setup, any client (be it a Web browser or an HTTP client such as curl) needs to present their TLS certificate and the Management Center needs to have its truststore configured so that the Management Center can know which clients it can trust. To enable mutual authentication, you need to use the following command line parameters when starting the Management Center:\n\n-Dhazelcast.mc.tls.mutualAuthentication=REQUIRED\n\nSee the below snippet to see the full command to start the Management Center:\n\n```java\njava -Dhazelcast.mc.tls.enabled=true \\\n -Dhazelcast.mc.tls.trustStore=path to your truststore \\\n -Dhazelcast.mc.tls.trustStorePassword=password for your truststore \\\n -Dhazelcast.mc.tls.mutualAuthentication=REQUIRED \\\n -jar hazelcast-management-center-4.0.2.war\n```\n\nThe parameter `-Dhazelcast.mc.tls.mutualAuthentication` has two options:\n\n- **REQUIRED**: If the client does not provide a keystore or the provided keys are not included in the Management Center's truststore, the client will not be authenticated.\n- **OPTIONAL**: If the client does not provide a keystore, it will be authenticated. But if the client provides keys that are not included in the Management Center's truststore, the client will not be authenticated.\n\nManaging Mutual Authentication Enabled Clusters\n\nIf mutual authentication is enabled for the cluster (as described here), the Management Center needs to have a keystore to identify itself. For this, you need to start the Management Center with the following command line parameters:\n\n- `-Dhazelcast.mc.httpClient.tls.keyStore`: Path to the keystore.\n- `-Dhazelcast.mc.httpClient.tls.keyStorePassword`: Password of the keystore.\n- `-Dhazelcast.mc.httpClient.tls.keyStoreType`: Type of the keystore. Its default value is JKS.\n-Dhazelcast.mc.httpClient.tls.keyManagerAlgorithm: Name of the algorithm based on which the authentication keys are provided. System default is used if none is provided. You can find out the default by calling the javax.net.ssl.KeyManagerFactory#getDefaultAlgorithm method.\n\n### Excluding Specific TLS/SSL Protocols\n\nWhen you enable TLS on the Management Center, it will support the clients connecting with any of the TLS/SSL protocols that the JVM supports by default. In order to disable specific protocols, you need to set the -Dhazelcast.mc.tls.excludeProtocols command line argument to a comma separated list of protocols to be excluded from the list of supported protocols. For example, to allow only TLSv1.2, you need to add the following command line argument when starting the Management Center:\n\n```\n-Dhazelcast.mc.tls.excludeProtocols=SSLv3,SSLv2Hello,TLSv1,TLSv1.1\n```\n\nWhen you specify the above argument, you should see a line similar to the following in the Management Center log:\n\n```\n```\n\n### 3.7.4. Using a Dictionary to Prevent Weak Passwords\n\nIn order to prevent certain words from being included in the user passwords, you can start the Management Center with -Dhazelcast.mc.security.dictionary.path command line parameter which points to a text file that contains a word on each line. As a result, the user passwords will not contain any dictionary words, making them harder to guess.\n\nThe words in the dictionary need to be at least three characters long in order to be used for checking the passwords. The shorter words are ignored to prevent them from blocking the usage of many password combinations. You can configure the minimum length of words by starting the Management Center with -Dhazelcast.mc.security.dictionary.minWordLength command line parameter and setting it to a number.\n\nAn example to start the Management Center using the aforementioned parameters is shown below:\n\n```\njava -Dhazelcast.mc.security.dictionary.path=/usr/MCtext/pwd.txt\n -Dhazelcast.mc.security.dictionary.minWordLength=3\n -jar hazelcast-management-center-4.0.2.war\n```\n\n### 3.8. Configuring Logging\n\nThe Management Center uses Logback for its logging. By default, it uses the following configuration:\nTo change the logging configuration, you can create a custom Logback configuration file and start the Management Center with the `-Dlogback.configurationFile` option pointing to your configuration file.\n\nFor example, you can create a file named `logback-custom.xml` with the following content and set logging level to `DEBUG`. To use this file as the logging configuration, you need to start the Management Center with the `-Dlogback.configurationFile=/path/to/your/logback-custom.xml` command line parameter:\nTo write log messages into rolling log files (in parallel with printing them into the console), you can use a similar Logback configuration file:\n\n```xml\n<configuration>\n <property name=\"pattern\" value=\"%d{yyyy-MM-dd HH:mm:ss} [%thread] %-5level %logger{36} - %msg%n\" />\n\n <appender name=\"STDOUT\" class=\"ch.qos.logback.core.ConsoleAppender\">\n <encoder>\n <pattern>${pattern}</pattern>\n </encoder>\n </appender>\n\n <appender name=\"FILE\" class=\"ch.qos.logback.core.rolling.RollingFileAppender\">\n <file>${user.home}/mc-logs/mc.log</file>\n <!-- daily rollover with last 7 days history -->\n <rollingPolicy class=\"ch.qos.logback.core.rolling.TimeBasedRollingPolicy\">\n <fileNamePattern>${user.home}/mc-logs/mc.%d{yyyy-MM-dd}.log</fileNamePattern>\n <maxHistory>7</maxHistory>\n </rollingPolicy>\n <encoder>\n <pattern>${pattern}</pattern>\n </encoder>\n </appender>\n\n <root level=\"INFO\">\n <appender-ref ref=\"STDOUT\"/>\n <appender-ref ref=\"FILE\"/>\n </root>\n</configuration>\n```\n\n```\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<configuration>\n <appender name=\"STDOUT\" class=\"ch.qos.logback.core.ConsoleAppender\">\n <encoder>\n <pattern>%d{yyyy-MM-dd HH:mm:ss} [%thread] %-5level %logger{36} - %msg%n</pattern>\n </encoder>\n </appender>\n\n <root level=\"DEBUG\">\n <appender-ref ref=\"STDOUT\"/>\n </root>\n</configuration>\n```\n3.8.1. Enabling Audit Logging\n\nYou may enable additional security audit logging by setting the `hazelcast.mc.auditlog.enabled` system property to `true`. Log entries from the audit logging will be marked with the `hazelcast.auditlog` logging category.\n\nAn example log entry looks like the following:\n\n```\n```\n\n**MC-2001 [Auth]** you see in this example represents the log's type. The following table lists the current log categories along with their types:\n\n<table>\n<thead>\n<tr>\n<th>Event Category</th>\n<th>Log Type/Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Management Center Configuration Logs</td>\n<td>• MC-0001 [Config]: Time travel is enabled.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-0002 [Config]: Time travel is disabled.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-0003 [Config]: User is created.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-0004 [Config]: User is edited.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-0005 [Config]: User's password is changed.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-0006 [Config]: User is deleted.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-0009 [Config]: License is set.</td>\n</tr>\n<tr>\n<td>Cluster Configuration Logs</td>\n<td>• MC-1001 [Cluster Config]: Map's configuration is changed.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-1003 [Cluster Config]: Cluster's state is changed.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-1004 [Cluster Config]: Cluster is shut down.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-1005 [Cluster Config]: Member is shut down.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-1006 [Cluster Config]: Lite member is promoted.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-1007 [Cluster Config]: Cluster version is changed.</td>\n</tr>\n<tr>\n<td>Authentication Logs</td>\n<td>• MC-2001 [Auth]: User logs in.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-2002 [Auth]: User logs out.</td>\n</tr>\n<tr>\n<td></td>\n<td>• MC-2003 [Auth]: Login failures.</td>\n</tr>\n<tr>\n<td>Scripting Logs</td>\n<td>• MC-3001 [Script]: Script is executed on a member.</td>\n</tr>\n<tr>\n<td>Console Logs</td>\n<td>• MC-4001 [Console]: Console command is executed on the cluster.</td>\n</tr>\n<tr>\n<td>Event Category</td>\n<td>Log Type/Description</td>\n</tr>\n<tr>\n<td>------------------------</td>\n<td>------------------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Map/Cache Logs</td>\n<td>• <strong>MC-5001 [Browser]</strong>: User browses through a map screen in Management Center.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-5002 [Browser]</strong>: User browses through a cache screen in Management Center.</td>\n</tr>\n<tr>\n<td>Hot Restart Logs</td>\n<td>• <strong>MC-6001 [Hot Restart]</strong>: Force start is run.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-6002 [Hot Restart]</strong>: Partial start is run.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-6003 [Hot Restart]</strong>: Hot Restart backup operation is triggered.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-6004 [Hot Restart]</strong>: Hot Restart backup operation is interrupted.</td>\n</tr>\n<tr>\n<td>WAN Replication Logs</td>\n<td>• <strong>MC-7001 [WAN]</strong>: WAN configuration is added.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-7002 [WAN]</strong>: WAN consistency check operation is run.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-7003 [WAN]</strong>: WAN synchronization on a map is run.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-7004 [WAN]</strong>: State of the WAN publisher is changed.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-7005 [WAN]</strong>: Clear operation for the WAN events queue is run.</td>\n</tr>\n<tr>\n<td>CP Subsystem Logs</td>\n<td>• <strong>MC-8001 [CP Subsystem]</strong>: Member is promoted to be a CP subsystem member.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-8002 [CP Subsystem]</strong>: Member is removed from CP subsystem.</td>\n</tr>\n<tr>\n<td></td>\n<td>• <strong>MC-8003 [CP Subsystem]</strong>: CP subsystem is reset.</td>\n</tr>\n</tbody>\n</table>\n\nTo write security audit logging into separate rolling log files, you can use a similar Logback configuration file:\n3.9. Using Variable Replacers\n\nVariable replacers are used to replace custom strings during loading the configuration, either passed as command line arguments, used during UI based Management Center configuration, or configured with Management Center Configuration Tool. They can be used to mask sensitive information such as usernames and passwords. Of course their usage is not limited to security related information.\n\nVariable replacers implement the interface com.hazelcast.webmonitor.configreplacer.spi.ConfigReplacer and they are configured via the following command line arguments:\n\n- -Dhazelcast.mc.configReplacer.class: Full class name of the replacer.\n- -Dhazelcast.mc.configReplacer.failIfValueMissing: Specifies whether the loading configuration\nprocess stops when a replacement value is missing. It is an optional attribute and its default value is true.\n\n- Additional command line arguments specific to each replacer implementation. All of the properties for the built-in replacers are explained in the upcoming sections.\n\nThe following replacer classes are provided by Hazelcast as example implementations of the ConfigReplacer interface. Note that you can also implement your own replacers.\n\n- EncryptionReplacer\n- PropertyReplacer\n\nEach example replacer is explained in the following sections.\n\n### 3.9.1. EncryptionReplacer\n\nThis example EncryptionReplacer replaces the encrypted variables with its plain form. The secret key for encryption/decryption is generated from a password which can be a value in a file and/or environment specific values, such as MAC address and actual user data.\n\nIts full class name is com.hazelcast.webmonitor.configreplacer.EncryptionReplacer and the replacer prefix is ENC. Here are the properties used to configure this example replacer:\n\n- **hazelcast.mc.configReplacer.prop.cipherAlgorithm**: Cipher algorithm used for the encryption/decryption. Its default value is AES.\n- **hazelcast.mc.configReplacer.prop.keyLengthBits**: Length (in bits) of the secret key to be generated. Its default value is 128.\n- **hazelcast.mc.configReplacer.prop.passwordFile**: Path to a file whose content should be used as a part of the encryption password. When the property is not provided, no file is used as a part of the password. Its default value is null.\n- **hazelcast.mc.configReplacer.prop.passwordNetworkInterface**: Name of the network interface whose MAC address should be used as a part of the encryption password. When the property is not provided no network interface property is used as a part of the password. Its default value is null.\n- **hazelcast.mc.configReplacer.prop.passwordUserProperties**: Specifies whether the current user properties (user.name and user.home) should be used as a part of the encryption password. Its default value is true.\n- **hazelcast.mc.configReplacer.prop.saltLengthBytes**: Length (in bytes) of a random password salt. Its default value is 8.\n- **hazelcast.mc.configReplacer.prop.secretKeyAlgorithm**: Name of the secret key algorithm to be associated with the generated secret key. Its default value is AES.\n- **hazelcast.mc.configReplacer.prop.secretKeyFactoryAlgorithm**: Algorithm used to generate a secret key from a password. Its default value is PBKDF2WithHmacSHA256.\n- **hazelcast.mc.configReplacer.prop.securityProvider**: Name of a Java Security Provider to be used for retrieving the configured secret key factory and the cipher. Its default value is null.\nAs a usage example, let’s create a password file and generate the encrypted strings out of this file as shown below:\n\n1. Create the password file:\n\n ```\n echo '/Za-uG3dDfpd,5.-' > /opt/master-password\n ```\n\n2. Define the encrypted variables:\n\n ```\n java -cp hazelcast-management-center-4.0.2.war \\\n -Dhazelcast.mc.configReplacer.prop.passwordFile=/opt/master-password \\n -Dhazelcast.mc.configReplacer.prop.passwordUserProperties=false \\n com.hazelcast.webmonitor.configreplacer.EncryptionReplacer \\\n \"aPasswordToEncrypt\"\n ```\n\n Output:\n\n ```\n $ENC{wJxe1vfHTgg=:531:WkAEdSi//YWEbwvVNoU9mUyZ0DE49acJea3mG4lHHfA=}\n ```\n\n3. Configure the replacer and provide the encrypted variables as command line arguments while starting the Management Center:\n\n ```\n java \\\n -Dhazelcast.mc.configReplacer.class=com.hazelcast.webmonitor.configreplacer.EncryptionReplacer \\n -Dhazelcast.mc.configReplacer.prop.passwordFile=/opt/master-password \\n -Dhazelcast.mc.configReplacer.prop.passwordUserProperties=false \\n -Dhazelcast.mc.tls.enabled=true \\n -Dhazelcast.mc.tls.keyStore=/opt/mc.keystore \\n -Dhazelcast.mc.tls.keyStorePassword='$ENC{wJxe1vfHTgg=:531:WkAEdSi//YWEbwvVNoU9mUyZ0DE49acJea3mG4lHHfA=}'} \\\n -jar hazelcast-management-center-4.0.2.war\n ```\n\n### 3.9.2. PropertyReplacer\n\n*PropertyReplacer* replaces variables by properties with the given name. Usually the system properties are used, e.g., `${user.name}`.\n\nIts full class name is `com.hazelcast.webmonitor.configreplacer.PropertyReplacer` and the replacer prefix is empty string (\"\").\n\n### 3.9.3. Implementing Custom Replacers\n\nYou can also provide your own replacer implementations. All replacers have to implement the three methods that have the same signatures as the methods of the following interface:\nimport java.util.Properties;\n\npublic interface ConfigReplacer {\n void init(Properties properties);\n String getPrefix();\n String getReplacement(String maskedValue);\n}\n\n4. Connecting to IMDG Members\n\nAfter you start and/or configure the Management Center service as explained in the Starting the Management Center Service and Configuring the Management Center chapters, make sure that http://localhost:8080 is up.\n\nTo connect the Management Center to your IMDG cluster, you have two options to be performed in Management Center:\n\n1. You can provide the IP addresses or hostnames of one or more IMDG members.\n\n2. Or, you can upload a configuration file in XML or YAML format. Management Center starts an IMDG client for each IMDG cluster. This configuration file is for that Management Center client. See the Launching Management Center chapter. You can think of the Management Center as a client connecting to the Hazelcast IMDG cluster.\n\nIf you enabled TLS/SSL on a Hazelcast IMDG cluster, then you need to perform the 2. step listed above, i.e., upload a configuration file. This configuration file needs to contain the parameters same as the ones you provide in the case when a client connects to a TLS/SSL enabled Hazelcast IMDG cluster.\n\n5. Launching the Management Center User Interface\n\nIf you have the open source edition of Hazelcast IMDG, the Management Center can be used for at most three members in the cluster. To use it for more members, you need to have either a Management Center license, Hazelcast IMDG Enterprise license or Hazelcast IMDG Enterprise HD license. The license should be entered within the Management Center as described in the following paragraphs.\n\nEven if you have a Hazelcast IMDG Enterprise or Enterprise HD license key and you set it as explained in the Setting the License Key section, you still need to enter this same license within the Management Center. See the following paragraphs to learn how you can enter your license.\n\nOnce you browse to http://localhost:8080 and since you are going to use the Management Center for the first time, the following dialog box appears:\nIf you already configured security before, a login dialog box appears instead.\n\nIt asks you to choose your security provider and create a username and password. Available security providers are Default, Active Directory, LDAP and JAAS, which are described in the following subsections.\n\nOnce you press the **Save** button, your security provider configuration is saved and you can log in with your credentials.\n\nAfter you successfully login, the following page appears:\nHazelcast\n\n**MANAGEMENT CENTER**\n\n- Manage Clusters\n- Settings\n- License\n\n**CLUSTER**\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Clients</td>\n</tr>\n<tr>\n<td>Members</td>\n</tr>\n<tr>\n<td>Administration</td>\n</tr>\n<tr>\n<td>License</td>\n</tr>\n<tr>\n<td>WAN Replication</td>\n</tr>\n<tr>\n<td>Scripting</td>\n</tr>\n<tr>\n<td>Console</td>\n</tr>\n</tbody>\n</table>\n\n**STORAGE**\n\n- Maps | 1 |\n- Replicated Maps | 1 |\n- Caches | 1 |\n- MultiMaps | 1 |\n- PN Counters | 0 |\n- ID Generators | 0 |\n\n**MESSAGING**\n\n- Queues | 1 |\n- Topics | 1 |\n- Reliable Topics | 1 |\n\n**COMPUTE**\n\n- Executors | 1 |\nNow, you can create an IMDG cluster configuration. See the Managing Clusters chapter.\n\nThe Management Center can be used without a license if the cluster that you want to monitor has at most three members.\n\nIf you have a Management Center license or Hazelcast IMDG Enterprise license, you can enter it by clicking on the Administration button on the left menu and opening the Manage License tab. Here you can enter your license key and press the Update License button, as shown below:\n\nNote that a license can likewise be provided using the system property hazelcast.mc.license (see the Starting with a License for details).\n\nWhen you try to connect to a cluster that has more than three members without entering a license key or if your license key is expired, the following warning message is shown at the top:\n\nIf you choose to continue without a license, please remember that the Management Center works if your cluster has at most three members.\n\nThe Management Center creates a folder with the name hazelcast-mc under your user's home folder to save data files and above settings/license information. You can change the data folder by setting the hazelcast.mc.home system property.\n\n5.1. Authentication Options\n\nAs mentioned above, available security providers are Default, Active Directory, LDAP and JAAS. They are described in the following below sections.\n\n5.1.1. Default Authentication\n\nYou can use the default security provider for authentication/authorization on the Management Center. In this case, the user accounts are stored in the Management Center's database.\nProvide the details in this form for the default security provider:\n\n- **Username**: Username for the initial administrator user account.\n- **Password, Confirm Password**: Password for the initial administrator user account.\n\nYou can also use the `create-user` command in the MC Conf tool to configure the default security provider without any UI interactions. See this command's [description](#) for details.\n\n### 5.1.2. Active Directory Authentication\n\nYou can use your existing Active Directory server for authentication/authorization on the Management Center. In the \"Configure Security\" page, select **Active Directory** from the \"Security Provider\" combo box, and the following form page appears:\n\nProvide the details in this form for your Active Directory server:\n\n- **URL**: URL of your Active Directory server, including the schema (`ldap://` or `ldaps://`) and port.\n- **Domain**: Domain of your organization on Active Directory.\n• **User Search Filter:** LDAP search filter expression to search for the users. \\{0\\} will be replaced with username@domain and \\{1\\} will be replaced with only the username. You can use both placeholders, only one of them or none in your search filter. For example, (objectClass=user)(userPrincipalName={0})) searches for a username that matches with the userPrincipalName attribute and member of the object class user.\n\n• **Admin Group(s):** Members of this group and its nested groups have admin privileges on the Management Center. To use more than one group, separate them with a semicolon (;).\n\n• **User Group(s):** Members of this group and its nested groups have read and write privileges on the Management Center. To use more than one group, separate them with a semicolon (;).\n\n• **Read-only User Group(s):** Members of this group and its nested groups have only read privilege on the Management Center. To use more than one group, separate them with a semicolon (;).\n\n• **Metrics-only Group(s):** Members of this group and its nested groups have the privilege to see only the metrics on Management Center. To use more than one group, separate them with a semicolon (;).\n\n• **Nested Group Search:** Disable if you have a large LDAP group structure and it takes a long time to query all nested groups during login.\n\n• **Test Username:** Username to test the Active Directory configuration with. Note that this value will not be saved and only be used for testing the Active Directory configuration.\n\n• **Test Password:** Password to test the Active Directory configuration with. Note that this value will not be saved and only be used for testing the Active Directory configuration.\n\nBefore saving the configuration, you can test it by clicking the Test button. Note that the user you test with needs to be a member of one of the groups you have configured for the Management Center.\n\nYou can use the hazelcast.mc.ldap.timeout system property to specify both connect and read timeout values for Active Directory search queries. It is in milliseconds and its default value is 3000 milliseconds.\n\n### Configuration Hot Reload\n\nOnce configured, Active Directory settings are saved in a local database managed by Management Center. If you need to update your settings afterwards, you need to provide the import properties file under <hazelcast-mc>/import/securityHotReload.properties, and then click on the Reload Security Config button on the login page. The securityHotReload.properties should contain the following properties:\n\n```\nurl=<active directory instance url>\ndomain=<domain>\nadminGroup=<Admin group(s). Use ',' to separate multiple groups>\nuserGroup=<Read-write group(s). Use ',' to separate multiple groups>\nreadonlyUserGroup=<Read-only group(s). Use ',' to separate multiple groups>\nmetricsOnlyGroup=<Metrics-only group(s). Use ',' to separate multiple groups>\n```\nThe **Reload Security Config** button will only appear when the `<hazelcast-mc>/import/securityHotReload.properties` file is present. After a successful import, the file will be renamed as `importedSecurityHotReload-<import_timestamp>.properties.bak`.\n\nAlternatively, you can use MC-Conf tool’s **security reset** and **active-directory configure** tasks to configure the Active Directory security provider from scratch, but you need to stop the Management Center service for this configuration option. See the Management Center Configuration Tool section for more information.\n\n### 5.1.3. JAAS Authentication\n\nYou can use your own `javax.security.auth.spi.LoginModule` implementation for authentication/authorization on the Management Center. In the \"Configure Security\" page, select **JAAS** from the “Security Provider” combo box, and the following page appears:\n\nProvide the details in this form for your JAAS **LoginModule** implementation:\n\n- **Login Module Class**: Fully qualified class name of your `javax.security.auth.spi/LoginModule` implementation.\n- **Admin Group**: Members of this group have admin privileges on the Management Center.\n- **User Group**: Members of this group have read and write privileges on the Management Center.\n- **Read-only User Group**: Members of this group have only read privilege on the Management Center.\n- **Metrics-only Group**: Members of this group have the privilege to see only the metrics on the Management Center.\n\nThe following is an example implementation. Note that we return two `java.security.Principal` instances; one of them is the username and the other one is a group name, which you will use when configuring JAAS security as described above.\nimport javax.security.auth.Subject;\nimport javax.security.auth.callback.Callback;\nimport javax.security.auth.callback.CallbackHandler;\nimport javax.security.auth.callback.NameCallback;\nimport javax.security.auth.callback.PasswordCallback;\nimport javax.security.auth.login>LoginException;\nimport javax.security.auth.spi>LoginModule;\nimport java.security.Principal;\nimport java.util.Map;\n\npublic class SampleLoginModule implements LoginModule {\n private Subject subject;\n private String password;\n private String username;\n\n @Override\n public void initialize(Subject subject, CallbackHandler callbackHandler, Map<String, ?> sharedState, Map<String, ?> options) {\n this.subject = subject;\n\n try {\n NameCallback nameCallback = new NameCallback(\"prompt\");\n PasswordCallback passwordCallback = new PasswordCallback(\"prompt\", false);\n\n callbackHandler.handle(new Callback[] {nameCallback, passwordCallback });\n\n password = new String(passwordCallback.getPassword());\n username = nameCallback.getName();\n } catch (Exception e) {\n throw new RuntimeException(e);\n }\n }\n\n @Override\n public boolean login() throws LoginException {\n if (!username.equals(\"emre\")) {\n throw new LoginException(\"Bad User\");\n }\n\n if (!password.equals(\"pass1234\")) {\n throw new LoginException(\"Bad Password\");\n }\n\n subject.getPrincipals().add(new Principal() {\n public String getName() {\n return \"emre\";\n }\n });\n\n subject.getPrincipals().add(new Principal() {\npublic String getName() {\n return \"HazelcastMCAdmin\";\n}\n\nreturn true;\n}\n\n@Override\npublic boolean commit() throws LoginException {\n return true;\n}\n\n@Override\npublic boolean abort() throws LoginException {\n return true;\n}\n\n@Override\npublic boolean logout() throws LoginException {\n return true;\n}\n\n5.1.4. LDAP Authentication\n\nYou can use your existing LDAP server for authentication/authorization on the Management Center. In the \"Configure Security\" page, select LDAP from the \"Security Provider\" combo box, and the following form page appears:\nProvide the details in this form for your LDAP server:\n\n- **URL**: URL of your LDAP server, including schema (ldap:// or ldaps://) and port.\n- **Distinguished name (DN) of user**: DN of a user that has admin privileges on the LDAP server. It is used to connect to the server when authenticating users.\n- **User DN**: DN to be used for searching users.\n- **Group DN**: DN to be used for searching groups.\n- **Admin Group(s)**: Members of this group and its nested groups have admin privileges on the Management Center. To use more than one group, separate them with a semicolon (;).\n- **User Group(s)**: Members of this group and its nested groups have read and write privileges on the Management Center. To use more than one group, separate them with a semicolon (;).\n- **Read-only User Group(s)**: Members of this group and its nested groups have only read privilege on the Management Center. To use more than one group, separate them with a semicolon (;).\n- **Metrics-only Group(s)**: Members of this group and its nested groups have the privilege to see only the metrics on the Management Center. To use more than one group, separate them with a semicolon (;).\n- **Start TLS**: Enable if your LDAP server uses Start TLS operation.\n- **User Search Filter**: LDAP search filter expression to search for the users. For example, `uid={0}`\nsearches for a username that matches with the uid attribute.\n\n- **Group Search Filter**: LDAP search filter expression to search for the groups. For example, uniquemember={0} searches for a group that matches with the uniquemember attribute.\n\n- **Nested Group Search**: Disable if you have a large LDAP group structure and it takes a long time to query all nested groups during login.\n\n Values for Admin, User, Read-only and Metrics-Only group names must be given as plain names. They should not contain any LDAP attributes such as CN, OU and DC.\n\nYou can use the hazelcast.mc.ldap.timeout system property to specify connect and read timeout values for LDAP search queries. It is in milliseconds and its default value is 3000 milliseconds.\n\n**Configuration Hot Reload**\n\nOnce configured, LDAP settings are saved in a local database managed by Management Center. If you need to update your settings afterwards, you need to provide the import properties file under <hazelcast-mc>/import/securityHotReload.properties, and then click on the Reload Security Config button on the login page. The securityHotReload.properties should contain the following properties:\n\n```\nurl=<Ldap URL>\nusername=<Distinguished name (DN) of user>\npassword=<password>\nuserDn=<User DN>\ngroupDn=<Group DN>\nstartTls=<true|false>\nadminGroup=<Admin group(s). Use ';' to separate multiple groups>\nuserGroup=<Read-write group(s). Use ';' to separate multiple groups>\nreadonlyUserGroup=<Read-only group(s). Use ';' to separate multiple groups>\nmetricsOnlyGroup=<Metrics-only group(s). Use ';' to separate multiple groups>\nuserSearchFilter=<User Search Filter>\ngroupSearchFilter=<Group Search Filter>\nnestedGroupSearch=<true|false>\n```\n\nThe Reload Security Config button will only appear when the <hazelcast-mc>/import/securityHotReload.properties file is present. After a successful import, the file will be renamed as importedSecurityHotReload-<import_timestamp>.properties.bak.\n\nAlternatively, you can use MC-Conf tool's security reset and active-directory configure tasks to configure the Active Directory security provider from scratch, but you need to stop the Management Center service for this configuration option. See the Management Center Configuration Tool section for more information.\nEnabling TLS/SSL for LDAP\n\nIf your LDAP server is using ldaps (LDAP over SSL) protocol or the Start TLS operation, use the following command line parameters for your Management Center deployment:\n\n- `-Dhazelcast.mc.ldap.ssl.trustStore`: Path to the truststore. This truststore needs to contain the public key of your LDAP server.\n- `-Dhazelcast.mc.ldap.ssl.trustStorePassword`: Password of the truststore.\n- `-Dhazelcast.mc.ldap.ssl.trustStoreType`: Type of the truststore. Its default value is JKS.\n- `-Dhazelcast.mc.ldap.ssl.trustManagerAlgorithm`: Name of the algorithm based on which the authentication keys are provided. System default is used if none is provided. You can find out the default by calling the `javax.net.ssl.TrustManagerFactory#DEFAULT_ALGORITHM` method.\n\nPassword Encryption\n\nBy default, the password that you use in the LDAP configuration is stored in a plain text in a local database. This might pose a security risk. To store the LDAP password in an encrypted form, we offer the following options:\n\n- **Provide a keystore password**: This creates and manages a Java keystore under the Management Center home directory. The LDAP password is stored in this keystore in an encrypted form.\n- **Configure an external Java keystore**: This uses an existing Java keystore. This option might also be used to store the password in an HSM that provides a Java keystore API.\n\nIn the case of using either one of the options, the LDAP password you enter on the initial configuration UI dialog will be stored in an encrypted form in a Java keystore instead of the local database.\n\nYou can also encrypt the password, and provide it in an encrypted form, when configuring LDAP security provider. See the Variable Replacers section for more information.\n\nProviding a Master Key for Encryption\n\nThere are two ways to provide a master key for encryption:\n\n- If you deploy the Management Center on an application server, you need to set the `MC_KEYSTORE_PASS` environment variable before starting Management Center. This option is less secure. You should clear the environment variable once you make sure you can log in with your LDAP credentials to minimize the security risk.\n- If you're starting the Management Center from the command line, you can start it with `-Dhazelcast.mc.askKeyStorePassword`. The Management Center asks for the keystore password upon start and use it as a password for the keystore it creates. This option is more secure as it only stores the keystore password in the memory.\n\nBy default, the Management Center creates a Java keystore file under the Management Center home directory with the name `mc.jceks`. You can change the location of this file by using the\n-Dhazelcast.mc.keyStore.path=/path/to/keyStore.jceks JVM argument.\n\nConfiguring an External Java KeyStore\n\nIf you don’t want the Management Center to create a keystore for you and use an existing one that you’ve created before (or an HSM), set the following JVM arguments when starting the Management Center:\n\n- **-Dhazelcast.mc.useExistingKeyStore=true**: Enables use of an existing keystore.\n- **-Dhazelcast.mc.existingKeyStore.path=/path/to/existing/keyStore.jceks**: Path to the keystore. You do not have to set it if you use an HSM.\n- **-Dhazelcast.mc.existingKeyStore.pass=somepass**: Password for the keystore. You do not have to set it if HSM provides another means to unlock HSM.\n- **-Dhazelcast.mc.existingKeyStore.type=JCEKS**: Type of the keystore.\n- **-Dhazelcast.mc.existingKeyStore.provider=com.yourprovider.MyProvider**: Provider of the keystore. Leave empty to use the system provider. Specify the class name of your HSM’s `java.security.Provider` implementation if you use an HSM.\n\nMake sure your keystore supports storing `SecretKey`s.\n\nUpdating Encrypted Passwords\n\nYou can use the `update-ldap-password` command in the MC Conf tool to update the encrypted LDAP password stored in the keystore. See this command’s description for details.\n\n6. User Interface Overview\n\nOnce the page is loaded after selecting a cluster, Dashboard Page appears as shown below:\nThis page provides the fundamental properties of the selected cluster which are explained in the Dashboard Page chapter.\n\nThe user interface has a toolbar on the top and a menu on the left.\n\n6.1. Toolbar\n\nThe toolbar has the following elements:\n\n- **Docs**: Opens the Management Center documentation in a new browser tab.\n- **Time Travel**: Shows the cluster's situation at a time in the past. See the Time Travel section.\n- **Console**: Opens the in-page console so that you can easily execute commands in your cluster. See the Executing Console Commands chapter. Note that this top menu item appears only when you select a cluster to monitor.\n- **User name**: Shows the current user's name. When you hover your mouse cursor onto it, the user's last login time is shown as a tooltip, for security purposes.\n- **Cluster Selector**: Switches between the clusters. When clicked on, a dropdown list of available clusters appears. You can select any cluster; once selected, the page immediately loads with the selected cluster's information. This selector has the same functionality as selecting a cluster in the \"Manage Clusters\" menu of the user interface.\n- **Logout**: Closes the current user's session.\n\n6.2. Menu\n\nThe Management Center user interface includes a menu on the left which lists the data structures in the cluster, cluster members and clients connected to the cluster (numbers in square brackets show the instance count for each entity), as shown below. You can also see an overview state of your cluster, execute commands and scripts, and perform user/license operations using this menu:\nWAN Replication button is only visible with the Hazelcast IMDG Enterprise license.\n\nThe menu consists of the following parent menu headings:\n\n- **Management Center**: Includes menu items to manage clusters, user and license operations, and examine the user interface logs.\n- **Cluster**: Includes menu items for general cluster operations, monitoring clients/cluster members and executing scripts/commands.\n- **Storage**: Includes menu items to monitor data structures such as the maps, caches and PN...\ncounters in your cluster.\n\n• **Messaging**: Includes menu items to monitor queues and topics in your cluster.\n\n• **Compute**: Includes the \"Executors\" menu item to monitor the executor services in your cluster.\n\nIf you have not selected a cluster to monitor, only the \"Management Center\" menu items are shown in the user interface.\n\nThe following is the list of all menu items with links to their explanations:\n\n- Managing Clusters\n- Settings\n- Management Center License\n- Dashboard\n- Clients\n- Members\n- Administration\n- Cluster License\n- WAN Replication\n- Scripting\n- Console\n- Maps\n- Replicated Maps\n- Caches\n- MultiMaps\n- PN Counters\n- ID Generators\n- Queues\n- Topics\n- Reliable Topics\n- Executors\n\n### 7. Managing Clusters\n\n\"Manage Clusters\" is the first page that appears after you login to Management Center. It is used to add, remove or edit cluster configurations, and looks like the following:\nMANAGEMENT CENTER\n\nManage Clusters\nSettings\nLicense\n\nCLUSTER\n\nStatus\nClients [ 4 ]\nMembers [ 3 ]\nAdministration\nLicense\nWAN Replication [ 0 ]\nScripting\nConsole\n\nSTORAGE\n\nMaps [ 1 ]\nReplicated Maps [ 1 ]\nCaches [ 1 ]\nMultiMaps [ 1 ]\nPN Counters [ 0 ]\nID Generators [ 0 ]\n\nMESSAGING\n\nQueues [ 1 ]\nTopics [ 1 ]\nReliable Topics [ 1 ]\n\nCOMPUTE\n\nExecutors [ 1 ]\nIf you are using Management Center for the first time, you need to add your cluster's configuration using this page. You can always go to this page during your Management Center usage by clicking on the \"Manage Clusters\" menu item under the \"Management Center\" parent menu heading.\n\nTo start monitoring your cluster you have already created (on your local machine, another development environment, etc.) you need to first define a cluster configuration to connect Management Center to your cluster. After you click on the \"Add Cluster Config\" button shown in the above screenshot, you can do this by either of the following options:\n\n- Using a form by providing the cluster name and member addresses\n- Uploading a configuration file\n\n### 7.1. Creating a Cluster Configuration Using Form\n\nClick on the \"Add Cluster Config\" button as seen in the above screenshot. The following page appears:\n\n- **Cluster Name**: Here, you enter the name of your cluster, which you defined while you were creating it. If you haven't specified anything, `dev` is the default name for a cluster.\n\n- **Cluster Config State**: Select \"Enabled\" to apply the cluster configuration. You can also select \"Disabled\" just to create the cluster configuration and use it at a later time. In this case, the configuration is ignored until you enable it.\n\n- **Member Addresses**: Give the cluster members' addresses (one or preferably more) in the form of `hostname`, `hostname:port`, `IP address` or `IP address:port`. If you don’t provide a port, the system tries the ports through 5701 and 5703 in a random order. Type the member address and press enter (or return) to make it visible in the \"Member Addresses\" field.\n\nClick on the **Save** button and the \"Manage Clusters\" page loads with the new cluster configuration added, as shown below:\nHere, you can see the state of the cluster and member count. Also, at the top left of the cluster box, you see the green colored dot, meaning that Management Center is connected to your cluster.\n\nYou can add multiple cluster configurations using the same mechanism as explained above.\n\nThe following page shows an example where Management Center is and is not able to connect one of clusters:\n\nYou can edit or delete a cluster configuration using the icons on any cluster’s box area in this page.\n\nTo see the status of a cluster, click on its Select button. The “Dashboard” page of the related cluster will load; see the Dashboard Page chapter for the details. Clicking on the Select button and selecting a cluster in the cluster selector (located at the toolbar) have the same functionality.\n\n### 7.2. Creating a Cluster Configuration by Uploading File\n\nAlternatively, you can upload a configuration file for the Management Center client created for your IMDG cluster. For this, click on the Upload Config File button which is seen after you click on the “Add Cluster Config” button. The following page appears:\nThe name of your cluster will be automatically generated as specified in the configuration file you upload. As mentioned before in the connecting members chapter, you can think of Management Center as a client that connects to your IMDG cluster you create. Therefore, this configuration file is a well-known `hazelcast.client` in XML or YAML language.\n\nHere is an example configuration file:\n\n**Example hazelcast-client.xml file**\n\n```xml\n<hazelcast-client>\n <cluster-name>dev</cluster-name>\n <network>\n <cluster-members>\n <address>127.0.0.1</address>\n <address>127.0.0.2</address>\n </cluster-members>\n </network>\n</hazelcast-client>\n```\n\nYou can simply drag this file onto the Cluster Config File box in this page, or find it using the browse link in the same box.\n\nSelect \"Enabled\" in the Cluster Config State combobox to apply the configuration. You can also select \"Disabled\" just to create the configuration and use it at a later time. In this case, the configuration is ignored until you enable it.\nYou can always go back to the form page (explained in the previous section) by clicking on the *Add via Form* on this page.\n\n## 8. Managing Users\n\nUser management is only available for the default security provider. See the [Default Authentication section](#) for more information.\n\nTo add a user to the system, specify the username, e-mail and password in the *Add/Edit User* part of the page. Then provide the user's privilege status using the checkboxes under *Permissions*:\n\n- **Admin**: Select if the user to be added will have the administrator privileges.\n- **Read/Write**: If this permission is given to the user, *Home*, *Scripting*, *Console*, *Documentation* and *Time Travel* items will be visible. The users with this permission can update a map configuration and perform operations on the members.\n- **Read**: If this permission is given to the user, only *Home*, *Documentation* and *Time Travel* items will be visible at the toolbar on that user's session. Also, the users with this permission cannot update a map configuration, run a garbage collection and take a thread dump on a\ncluster member, or shutdown a member (see the Monitoring Members section).\n\n- **Metrics Only**: If this permission is given to the user, only Home, Documentation and Time Travel items will be visible at the toolbar on that user's session. Also, the users with this permission cannot browse a map or a cache to see their contents, cannot update a map configuration, run a garbage collection and take a thread dump on a cluster member, or shutdown a member (see the Monitoring Members section).\n\nAfter you enter/select all the fields, click on the Save button to create the user. You will see the newly created user's username on the right side, in the List of Users part of the page.\n\nTo edit or delete a user, click on its username listed in the List of Users. Selected user information appears on the left side of the page. To update the user information, change the fields as desired and click on the Save button; note that you can only change the username and/or its privilege.\n\nYou can also change a user's password or delete the user account. To change the user's password, click on the Change Password button while editing the user. To delete the user from the system, click on the Delete button. Note that changing the password of a user and deleting the user account both require you to enter your own password.\n\nCertain user management operations are also available in the MC Conf tool. See the Management Center Configuration Tool section for more information.\n\n9. Managing Licenses\n\nYou can manage the following types of licenses in Management Center:\n\n- License for Management Center\n- License for your Hazelcast product\n\n9.1. Management Center License\n\nUsing the \"License\" menu item under the \"Management Center\" parent menu heading, you can view the details of your Management Center license. An example screenshot is shown below.\n\n<table>\n<thead>\n<tr>\n<th>Management Center License Details</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>License Key Hash</td>\n</tr>\n<tr>\n<td>Expires</td>\n</tr>\n<tr>\n<td>Licensed Cluster Members</td>\n</tr>\n<tr>\n<td>License Type</td>\n</tr>\n</tbody>\n</table>\n\nIt shows the expiration date, total licensed member count and type of your Management Center license.\n\nFor security reasons, the license key itself is not shown. Instead, SHA-256 hash of the key as a Base64 encoded string is shown.\n\nIf there are any problems related to your Management Center license, \"License\" menu item is\nhighlighted with red exclamation points. In this case, please check this screen to see what the problem is. The following are the possible problems:\n\n- Your Management Center license is expired.\n- The count of your cluster members is more than the allowed count by the license.\n\nIf the Management Center license expires in 30 days or less, or has already expired, a warning will appear in the upper right corner once a day. Warning will contain time remaining until license expires or how long the license is expired. There will also be two buttons - the first one with label \"Show License\" will redirect you to the license page, the second one with label \"Dismiss Alert\" will dismiss the alert. An example screenshot is shown below.\n\nTo update the Management Center license, you can open the Manage License tab and click on the Update License button and enter the new license code.\n\nAlternatively, a license can be provided using the `hazelcast.mc.license` system property (see the Starting with a License section for details).\n\n### 9.2. Cluster License\n\nUsing the \"License\" menu item under the \"Cluster\" parent menu heading, you can view the details of your cluster's license (Hazelcast IMDG license). An example screenshot is shown below.\n\n<table>\n<thead>\n<tr>\n<th>Cluster License Details</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>License Key Hash</td>\n</tr>\n<tr>\n<td>Expires</td>\n</tr>\n<tr>\n<td>Licensed Cluster Members</td>\n</tr>\n<tr>\n<td>License Type</td>\n</tr>\n</tbody>\n</table>\n\nIt shows the expiration date, total licensed member count and type of your Hazelcast IMDG license.\nFor security reasons, the license key itself is not shown. Instead, SHA-256 hash of the key as a Base64 encoded string is shown.\n\nIf there are any problems related to your cluster license, “License” menu item is highlighted with red exclamation points. In this case, please check this screen to see what the problem is. The following are the possible problems:\n\n- Your Hazelcast IMDG license is expired.\n- The count of your cluster members is more than the allowed count by the license.\n\nIf the cluster license expires in 30 days or less, or has already expired, a warning will appear in the upper right corner once a day, similar to the one for the Management Center license. Warning will contain time remaining until license expires or how long the license is expired. There will also be two buttons - the first one with label \"Show License\" will redirect you to the license page, the second one with label \"Dismiss Alert\" will dismiss the alert.\n\n10. Dashboard Page\n\nThis is the first page appearing after logging in. It gives an overview of the connected cluster. The following subsections describe each portion of the page.\n\n10.1. Memory Utilization\n\nThis part of the page provides information related to the memory usages for each member, as shown below:\n\n<table>\n<thead>\n<tr>\n<th>Member</th>\n<th>Used Heap</th>\n<th>Total Heap</th>\n<th>Max. Heap</th>\n<th>Max. Used Percentage</th>\n<th>Used Heap</th>\n<th>Native Memory Max</th>\n<th>Native Memory Used</th>\n<th>Native Memory Free</th>\n<th>GC Major Count</th>\n<th>GC GC Minor Count</th>\n<th>GC GC Minor Time</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>270.63 KB</td>\n<td>46.67 KB</td>\n<td>54.41 KB</td>\n<td>7.63%</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>1</td>\n<td>24 ms</td>\n<td>7</td>\n</tr>\n<tr>\n<td></td>\n<td>270.63 KB</td>\n<td>46.67 KB</td>\n<td>54.41 KB</td>\n<td>7.63%</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>1</td>\n<td>24 ms</td>\n<td>7</td>\n</tr>\n<tr>\n<td></td>\n<td>270.63 KB</td>\n<td>46.67 KB</td>\n<td>54.41 KB</td>\n<td>7.63%</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>1</td>\n<td>24 ms</td>\n<td>7</td>\n</tr>\n</tbody>\n</table>\n\nThe first column lists the members with their IPs and ports. The next columns show the used and free memories out of the total memory reserved for Hazelcast IMDG usage, in real-time. The **Max. Heap** column lists the maximum memory capacity of each member and the **Heap Usage Percentage** column lists the percentage value of used memory out of the maximum memory. The **Used Heap** column shows the memory usage of members graphically. When you move the mouse cursor on a desired graph, you can see the memory usage at the time where the cursor is placed. Graphs under this column show the memory usages approximately for the last 2 minutes.\n\n10.2. Heap Memory Distribution\n\nThis part of the page graphically provides the cluster wise breakdown of heap memory, as shown below. The blue area is the heap memory used by the maps (including all owned/backup entries, any near cache usage and cost of the Merkle tree). The dark yellow area is the heap memory used by both non-Hazelcast entities and all Hazelcast entities except the map, i.e., the heap memory used...\nby all entities subtracted by the heap memory used by map. The green area is the free heap memory out of the whole cluster's total committed heap memory.\n\nIn the above example, you can see about 3% of the total heap memory is used by Hazelcast IMDG maps, about 30% is used by both non-Hazelcast entities and all Hazelcast entities except the map and the rest of the total heap memory is free. You can see the exact percentages by placing the mouse cursor on the chart.\n\n10.3. Cluster State/Health/Client Filtering/CP Subsystem\n\nThis part has the following status indicator elements:\n\n- **Cluster State**: Shows the current cluster state. For more information on cluster states, see the Cluster State section.\n- **Cluster Health**: Shows how many migrations are taking place currently.\n- **Cluster Filtering**: Shows values for the current cluster client filtering status and type. For more information on the cluster client filtering, see the Changing Cluster Client Filtering section.\n- **CP Subsystem**: Shows the CP subsystem status. For more information on the CP subsystem support in the Management Center, see the CP Subsystem section.\n\nCluster client filtering is only available with Hazelcast IMDG license that includes the Cluster Client Filtering feature.\n10.4. Partition Distribution\n\nThis chart shows what percentage of partitions each cluster member has, as shown below:\n\nYou can see each member's partition percentages by placing the mouse cursor on the chart. In the above example, you can see that each member has about 33.3% of the total partition count (which is 271 by default and configurable; see the `hazelcast.partition.count` property explained in the System Properties section in the Hazelcast IMDG Reference Manual).\n\nThe partition distribution chart does not show any information until you create your distributed objects. When you add new members to your cluster, there will be no partition migration since partitions do not exist yet. Once you connect to your cluster and, for example, create a map (using `hazelcastInstance.getMap()`), only then this chart starts to show partition distribution information.\n\n10.5. CPU Utilization\n\nThis part of the page provides load and utilization information for the CPUs for each cluster member, as shown below:\nThe first column lists the members with their IPs and ports. The next columns list the system load averages on each member for the last 1, 5 and 15 minutes. These average values are calculated as the sum of the count of runnable entities running on and queued to the available CPUs averaged over the last 1, 5 and 15 minutes. This calculation is operating system specific, typically a damped time-dependent average. If system load average is not available, these columns show negative values.\n\nThe last column (Utilization(%) graphically shows the recent load on the CPUs. When you move the mouse cursor on a chart, you can see the CPU load at the time where the cursor is placed. The charts under this column shows the CPU loads approximately for the last 2 minutes. If recent CPU load is not available, you will see N/A values.\n\n11. Monitoring Members\n\nUse this menu item to monitor each cluster member and perform operations like running garbage collection (GC) and taking a thread dump.\n\nYou can see a list of all the members in your cluster by clicking on the Members menu item on the left panel. A new page is opened on the right, as shown below.\n\nYou may see a warning icon with exclamation mark in the list when your runtime or hardware configuration does not follow the performance recommendations. See IMDG Deployment and Operations Guide for more information.\nYou can filter the members shown and you can also sort the table by clicking on the column headers. Members that participate in the **CP subsystem** are marked with the CP icon. Clicking on a member name opens a new page for monitoring that member on the right, as shown below.\n\nYou can perform the following operations on the selected member using the buttons located at the top left of the page:\n\n- **Run GC**: Executes garbage collection on the selected member. A notification stating that the GC execution was successful is shown.\n- **Thread Dump**: Takes a thread dump of the selected member and shows it in a separate dialog.\n- **Shutdown Member**: Shuts down the selected member.\n- **Promote Member**: It is only shown for the lite members. When pressed, the lite member becomes a data member.\n\n**Shutdown member operation requires enabled REST API in the IMDG cluster. See the IMDG documentation for more information.**\n\nNext to the above operation buttons, you can see the informative buttons as described below:\n- **Number of Owned Partitions**: Shows how many partitions are assigned to the selected member.\n\n- **Member Version**: Shows the Hazelcast IMDG cluster version which the selected member belongs to.\n\n- **CP Member UUID**: Shows CP member UUID if the member participates in the CP subsystem of the cluster.\n\nThe **CPU Utilization** chart shows the percentage of CPU usage on the selected member. The **Heap/Memory Utilization** charts show the memory usage on the selected member with three different metrics (maximum, used and total memory). You can open each chart as a separate dialog using the button placed at top right of them; this gives you a clearer view of the chart.\n\n**Runtime** is a dynamically updated window tab showing the processor number, the start and up times, and the maximum, total and free memory sizes of the selected member. These values are collected from the default MXBeans provided by the Java Virtual Machine (JVM). Descriptions from the Javadocs and some explanations are below:\n\n- **Number of Processors**: Number of processors available to the member (JVM).\n- **Start Time**: Start time of the member (JVM) in milliseconds.\n- **Up Time**: Uptime of the member (JVM) in milliseconds.\n- **Maximum Memory**: Maximum amount of memory that the member (JVM) will attempt to use.\n- **Free Memory**: Amount of free memory in the member (JVM).\n- **Used Heap Memory**: Amount of used memory in bytes.\n- **Max Heap Memory**: Maximum amount of memory in bytes that can be used for memory management.\n- **Used Non-Heap Memory**: Amount of used memory in bytes.\n- **Max Non-Heap Memory**: Maximum amount of memory in bytes that can be used for memory management.\n- **Total Loaded Classes**: Total number of classes that have been loaded since the member (JVM) has started execution.\n- **Current Loaded Classes**: Number of classes that are currently loaded in the member (JVM).\n- **Total Unloaded Classes**: Total number of classes unloaded since the member (JVM) has started execution.\n- **Total Thread Count**: Total number of threads created and also started since the member (JVM) started.\n- **Active Thread Count**: Current number of live threads including both daemon and non-daemon threads.\n- **Peak Thread Count**: Peak live thread count since the member (JVM) started or peak was reset.\n- **Daemon Thread Count**: Current number of live daemon threads.\n- **OS: Free Physical Memory**: Amount of free physical memory in bytes.\n- **OS: Committed Virtual Memory**: Amount of virtual memory that is guaranteed to be available...\nto the running process in bytes.\n\n- **OS: Total Physical Memory**: Total amount of physical memory in bytes.\n\n- **OS: Free Swap Space**: Amount of free swap space in bytes. Swap space is used when the amount of physical memory (RAM) is full. If the system needs more memory resources and the RAM is full, inactive pages in memory are moved to the swap space.\n\n- **OS: Total Swap Space**: Total amount of swap space in bytes.\n\n- **OS: Maximum File Descriptor Count**: Maximum number of file descriptors. File descriptor is an integer number that uniquely represents an opened file in the operating system.\n\n- **OS: Open File Descriptor Count**: Number of open file descriptors.\n\n- **OS: Process CPU Time**: CPU time used by the process on which the member (JVM) is running in nanoseconds.\n\n- **OS: Process CPU Load**: Recent CPU usage for the member (JVM) process. This is a double with a value from 0.0 to 1.0. A value of 0.0 means that none of the CPUs were running threads from the member (JVM) process during the recent period of time observed, while a value of 1.0 means that all CPUs were actively running threads from the member (JVM) 100% of the time during the recent period being observed. Threads from the member (JVM) include the application threads as well as the member (JVM) internal threads.\n\n- **OS: System Load Average**: System load average for the last minute. The system load average is the average over a period of time of this sum: (the number of runnable entities queued to the available processors) + (the number of runnable entities running on the available processors). The way in which the load average is calculated is operating system specific but it is typically a damped time-dependent average.\n\n- **OS: System CPU Load**: Recent CPU usage for the whole system represented as a percentage value. 0% means that all CPUs were idle during the recent period of time observed, while 100% means that all CPUs were actively running during the recent period being observed.\n\nThese descriptions may vary according to the JVM version or vendor.\n\nNext to the **Runtime** tab, the **Properties** tab shows the system properties.\n\nThe **Member Configuration** window shows the XML configuration of the connected Hazelcast cluster.\n\nThe **List of Slow Operations** gives an overview of detected slow operations which occurred on that member. The data is collected by the **SlowOperationDetector**.\n\nClick on an entry to open a dialog which shows the stacktrace and detailed information about each slow invocation of this operation.\n12. Monitoring Clients\n\nYou can use the Clients menu item to monitor all the clients that are connected to your Hazelcast cluster.\n\nOnly basic information for clients, like client instance name, address, type and labels, is shown by default. The values for other fields are shown as N/A. As a prerequisite for seeing the full information, you need to enable the client statistics before starting your clients. This can be done by setting the `hazelcast.client.statistics.enabled` system property to `true` on the client. Please see the Client System Properties section in the Hazelcast IMDG Reference Manual for more information. After you enable the client statistics, you can monitor your clients using Hazelcast Management Center.\n\nYou can see a list of all the clients in your cluster by clicking on the Clients menu item on the left panel. A new page is opened on the right, as shown below. The page has two tabs: Connection and Filter. The Connection tab is opened by default. This tab shows the list of all the clients. See the Changing Cluster Client Filtering section for the Filter tab’s description.\n\nBy default, hostname of the client is shown in the address column. You can change it to show its IP address or its canonical hostname instead by using the Address Type combo box. Note that this will also cause the client details page to show the IP address or the canonical hostname.\n\nYou can filter the clients shown and you can also sort the table by clicking on the column headers. Clicking on a client name will open a new page for monitoring that client on the right, as shown\nThe **Heap Memory Utilization** chart shows the memory usage on the selected client with three different metrics (maximum, used and total memory) represented by different colors. You can open this chart as a separate window using the button placed at top right of it; this gives you a clearer view of the chart.\n\n**General** is a dynamically updated window tab showing general information about the client. Below are brief explanations for each piece of information:\n\n- **Name**: Name of the client instance.\n- **Address**: Local IP address of the client that is used for connecting to members.\n- **Type**: Type of the client.\n- **Enterprise**: Yes, if the client is an Hazelcast IMDG Enterprise client.\n- **Member Connection**: Shows to which member a client is currently connected to. Please note that ALL means a client is configured so that it **might** connect to all members of a cluster, i.e., it might not have a connection to all members all the time.\n- **Version**: Version of the client.\n- **Last Connection to Cluster**: Time that the client connected to the cluster. It is reset on each reconnection.\n- **Last Statistics Collection**: Time when the latest update for the statistics is collected from the client.\n- **User Executor Queue Size**: Number of waiting tasks in the client user executor.\n- **Labels**: List of client labels.\nNext to the **General** tab, the **Runtime** tab shows the processor number, uptime, and maximum, total and free memory sizes of the selected client. These values are collected from the default MXBeans provided by the Java Virtual Machine (JVM). Descriptions from the Javadocs and some explanations are below:\n\n- **Number of Processors**: Number of processors available to the client (JVM).\n- **Up Time**: Uptime of the client (JVM).\n- **Maximum Memory**: Maximum amount of memory that the client (JVM) will attempt to use.\n- **Total Memory**: Amount of total heap memory currently available for current and future objects in the client (JVM).\n- **Free Memory**: Amount of free heap memory in the client (JVM).\n- **Used Memory**: Amount of used heap memory in the client (JVM).\n\nNext to the **Runtime** tab, the **OS** tab shows statistics about the operating system of the client. These values are collected from the default MXBeans provided by the Java Virtual Machine (JVM). Descriptions from the Javadocs and some explanations are below:\n\n- **Free Physical Memory**: Amount of free physical memory.\n- **Committed Virtual Memory**: Amount of virtual memory that is guaranteed to be available to the running process.\n- **Total Physical Memory**: Total amount of physical memory.\n- **Free Swap Space**: Amount of free swap space. Swap space is used when the amount of physical memory (RAM) is full. If the system needs more memory resources and the RAM is full, inactive pages in memory are moved to the swap space.\n- **Total Swap Space**: Total amount of swap space.\n- **Maximum File Descriptor Count**: Maximum number of file descriptors. File descriptor is an integer number that uniquely represents an opened file in the operating system.\n- **Open File Descriptor Count**: Number of open file descriptors.\n- **Process CPU Time**: CPU time used by the process on which the member (JVM) is running.\n- **System Load Average**: System load average for the last minute. The system load average is the average over a period of time of this sum: (the number of runnable entities queued to the available processors) + (the number of runnable entities running on the available processors). The way in which the load average is calculated is operating system specific but it is typically a damped time-dependent average.\n\nSome of the Runtime/OS statistics may not be available for your client’s JVM implementation/operating system. N/A is shown for these types of statistics. Please refer to your JVM/operating system documentation for further details.\n\nThe **Client Near Cache Statistics** table shows statistics related to the Near Cache of a client. There are two separate tables; one for maps and one for caches.\n\n- **Map/Cache Name**: Name of the map or cache.\n• **Creation Time**: Creation time of this Near Cache on the client.\n\n• **Evictions**: Number of evictions of Near Cache entries owned by the client.\n\n• **Expirations**: Number of TTL and max-idle expirations of Near Cache entries owned by the client.\n\n• **Hits**: Number of hits (reads) of Near Cache entries owned by the client.\n\n• **Misses**: Number of misses of Near Cache entries owned by the client.\n\n• **Owned Entry Count**: Number of Near Cache entries owned by the client.\n\n• **Owned Entry Memory Cost**: Memory cost of Near Cache entries owned by the client.\n\n• **LP Duration**: Duration of the last Near Cache key persistence (when the pre-load feature is enabled).\n\n• **LP Key Count**: Number of Near Cache key persistences (when the pre-load feature is enabled).\n\n• **LP Time**: Time of the last Near Cache key persistence (when the pre-load feature is enabled).\n\n• **LP Written Bytes**: Written number of bytes of the last Near Cache key persistence (when the pre-load feature is enabled).\n\n• **LP Failure**: Failure reason of the last Near Cache persistence (when the pre-load feature is enabled).\n\nPlease note that you can configure the time interval for which the client statistics are collected and sent to the cluster, using the system property `hazelcast.client.statistics.period.seconds`. See the System Properties section in the Hazelcast IMDG Reference Manual for more information.\n\n### 12.1. Changing Cluster Client Filtering\n\nThe Filter tab is only available with Hazelcast IMDG license that includes the Cluster Client Filtering feature.\n\nThe **Filter** tab includes **Cluster Client Filtering** status, **Cluster Client Filter Settings** and **Client Filtering Lists** sections, as shown below.\n\nThe **Cluster Client Filtering** status section describes if there is a deployed client filtering list\navailable to all cluster members (Enabled status), or if the feature is disabled for the cluster and the members allow any clients (Disabled status).\n\nThe Cluster Client Filter Settings section allows to specify the status of the feature and the filtering type and to deploy any modifications made in client filtering lists to the deployed list available to all cluster members. On the deploy action the following happens:\n\n- If the status to be deployed is Disabled, the deployed client filtering list available to all cluster members is cleaned up and the members start allowing any client to connect.\n- If the status to be deployed is Enabled, all entries of the matching lists from the Client Filtering Lists section are copied into the deployed client filtering list and applied to all cluster members. Matching lists are selected by their status (List Status must be Active) and type (List Type must match the value of the Client Filter Type selection).\n\nOnce a cluster member receives the deployed client filtering list from the Management Center, it immediately applies the list to all currently connected clients and then uses it for newly connecting clients. Blacklisted clients may connect to another cluster if they are configured to support blue-green deployment. Please see the Blue-Green Deployment and Disaster Recovery section in the Hazelcast IMDG Reference Manual for more information.\n\nIf some of the cluster members are not reachable from the Management Center, those members keep using the last client list applied to them.\n\nThe deploy action in the Cluster Client Filter Settings section is available by clicking on the Deployed/Deploy Changes button. This button also describes if there were any changes in client filtering lists that would lead to changes in the deployed client filtering list as the result of the deploy (Deploy Changes label), or there were no such changes (Deployed label).\n\nThe Client Filtering Lists section allows creation, editing and deletion of the client filtering lists. To create a new client filtering list, you need to click the Add New List button, which will open the Create List form, as shown below. Once you enter all fields and entries for the new list, click the Save button to save your modifications.\n\nThe following formats of list entry values are supported:\n\n- For the IP Address entry type you can specify IP address (IPv4 or IPv6) with optional range characters (\\* and -) instead of any byte group. For instance, 10.3.10.\\* refers to IPs between 10.3.10.0 and 10.3.10.255. The 10.3.10.4-18 refers to IPs between 10.3.10.4 and 10.3.10.18 (4 and 18 included).\n- For the Label entry type you can specify any string with optional wildcard characters (\\*). For\ninstance, green* refers to any label values that start with the green string.\n\n- For the Instance Name entry type you can specify any string with optional wildcard characters (*). For instance, *-client refers to any label values that end with the -client string.\n\nTo modify an existing client filtering list, you need to click the Edit button, which will open the Edit List form, as shown below.\n\nTo delete an existing client filtering list, you need to click the Delete button and confirm your action in the opened dialog.\n\nAny modifications made in the Client Filtering Lists section will become available to members only after the deploy action.\n\n13. Monitoring Data Structures\n\nThis chapter provides information on how you can monitor the Hazelcast data structures in your cluster.\n\n13.1. Maps\n\nYou can see a list of all the maps in your cluster by clicking on the Maps menu item on the left panel. A new page is opened on the right, as shown below.\nYou can filter the maps shown and you can also sort the table by clicking on the column headers. Clicking on a map name opens a new page for monitoring that map instance on the right, as shown below.\nThe below subsections explain the portions of this window.\n\n### 13.1.1. Map Browser\n\nUse the Map Browser tool to retrieve properties of the entries stored in the selected map. To open the Map Browser tool, click on the **Map Browser** button, located at the top right of the window. Once opened, the tool appears as a dialog, as shown below.\n\n\n\n<table>\n<thead>\n<tr>\n<th>Field</th>\n<th>Value</th>\n<th>Type</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Value</td>\n<td>Konya</td>\n<td>java.lang.String</td>\n<td></td>\n</tr>\n<tr>\n<td>Memory Cost</td>\n<td>85.00 B</td>\n<td></td>\n<td>Friday, January 24th 2020, 9:49:59 am</td>\n</tr>\n<tr>\n<td>Creation Time</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Hits</td>\n<td>0</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Last Update Time</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Version</td>\n<td>0</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Time to Live</td>\n<td>N/A</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Max Idle</td>\n<td>N/A</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nOnce the key and the key’s type are specified and the **Browse** button is clicked, the key’s properties along with its value are listed.\n\nIf you are using a serialization mechanism other than standard Java serialization for storing values in your map, you need to configure the client that Management Center uses for connecting to the cluster (as described [here](#)). Note that if you have any custom classes, you need to add the JAR containing them to Management Center’s classpath before starting it as described in [Providing an Extra Classpath](#). In case the value stored in the map is not a **String** or of another Java primitive type, it is rendered as a JSON value as shown below:\n13.1.2. Map Config\n\nUse the Map Config tool to set the selected map's attributes, such as the backup count, TTL, and eviction policy. To open the Map Config tool, click on the Map Config button, located at the top right of the window. Once opened, the tool appears as a dialog, as shown below.\n13.1.3. Map Monitoring\n\nBesides the Map Browser and Map Config tools, the map monitoring page has monitoring options that are explained below. All of these options perform real-time monitoring.\n\nOn top of the page, small charts monitor the entries, operations per second, memory usage, backup size, etc. of the selected map in real-time. The X-axis of all the charts show the current system time. You can select other small monitoring charts using the button at the top right of each chart. When you click the button, the monitoring options are listed, as shown below.\n\nWhen you click on a desired monitoring, the chart is loaded with the selected option. To open a chart as a separate dialog, click on the button placed at the top right of each chart. The monitoring charts below are available:\n\n- **Entries**: Monitors number of locally owned entries.\n- **Memory**: Monitors the total memory cost of locally owned entries.\n- **Backups**: Monitors number of backup entries.\n- **Backup Memory**: Monitors the total memory cost of backup entries.\n- **Hits**: Monitors number of hits (reads) of locally owned entries, including those which are no longer in the map (for example, may have been evicted). The number of hits may be inaccurate after a partition is migrated to a new owner member.\n- **Locks**: Monitors number of locally owned entries that are locked.\n- **Operations/s**: Monitors the total number of all operations performed on the map per second.\n- **Puts/s, Gets/s, Removes/s**: These three charts monitor the put, get and remove operations performed on the map per second.\n\nUnder these charts are Map Statistics, Map Throughput, Member Near Cache, and Client Near Cache data tables.\n\nMap Statistic Data Table provides statistics distributed over the members, as shown below.\nFrom left to right, this table lists the following:\n\n- **Members**: IP address and port of the member.\n- **Entries**: Number of entries owned by the member.\n- **Gets**: Number of get operations received by the member.\n- **Puts**: Number of put operations received by the member.\n- **Removes**: Number of remove operations received by the member.\n- **Entry Memory**: Memory cost of owned entries in the member.\n- **Backups**: Number of backup entries held by the member.\n- **Backup Memory**: Memory cost of backup entries held by the member.\n- **Events**: Number of events received by the member.\n- **Hits**: Number of hits (reads) of the entries that are owned by the member, including those which are no longer in the map (for example, may have been evicted). The number of hits may be inaccurate after a partition is migrated to a new owner member.\n- **Locks**: Number of currently locked entries owned by the member.\n- **Dirty Entries**: Number of entries that the member owns and are dirty (updated but not persisted yet). In the cases where MapStore is enabled, these are the entries that are put to/removed from the map but not written to/removed from a database yet.\n\nYou can ascend or descend the order of the listings by clicking on the column headings.\n\n**Map Throughput Data Table** provides information about the operations (get, put, remove) performed on each member in the map, as shown below.\n\nFrom left to right, this table lists the following:\n\n- **Members**: IP address and port of the member.\n- **Puts/s**: Number of put operations per second on the member.\n- **Gets/s**: Number of get operations per second on the member.\n- **Removes/s**: Number of remove operations per second on the member.\n- **Avg Put Latency**: Average latency of put operations on the member.\n- **Avg Get Latency**: Average latency of get operations on the member.\n• **Avg Remove Latency**: Average latency of remove operations on the member.\n• **Max Put Latency**: Maximum latency of put operations on the member.\n• **Max Get Latency**: Maximum latency of get operations on the member.\n• **Max Remove Latency**: Maximum latency of remove operations on the member.\n\nYou can select the time period in the combo box placed on the top right corner of the window, for which the table data will be shown. Available values are **Since Beginning, Last Minute, Last 10 Minutes** and **Last 1 Hour**.\n\nTo ascend or descend the order of the listings, click on the column headings.\n\n**Member Near Cache Data Table** provides information about the Member Near Caches, if available, on each member, as shown below.\n\n<table>\n<thead>\n<tr>\n<th>Member Near Cache Data Table</th>\n<th>Members</th>\n<th>Entries</th>\n<th>Entry Memory</th>\n<th>Hits</th>\n<th>Misses</th>\n<th>Ratio</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>127.0.0.1:57601</td>\n<td>2</td>\n<td>152,000 bytes</td>\n<td>191</td>\n<td>3558</td>\n<td>4.88</td>\n<td></td>\n</tr>\n<tr>\n<td>127.0.0.1:57602</td>\n<td>2</td>\n<td>188,000 bytes</td>\n<td>197</td>\n<td>3133</td>\n<td>6.30</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nFrom left to right, this table lists the following:\n\n• **Members**: IP address and port of the member which has Near Caches defined for the maps.\n• **Entries**: Count of the entries in each Near Cache.\n• **Entry Memory**: Memory cost of the entries in each Near Cache.\n• **Hits**: Count of the entries read from the Near Cache.\n• **Misses**: Count of the entries which cannot be found in the Near Cache when requested to read.\n• **Ratio**: Hits/Misses ratio.\n\nTo ascend or descend the order of the listings, click on the column headings.\n\n**Client Near Cache Summary** provides summary information related to the Near Cache statistics aggregated for all the clients that have Near Cache enabled for this map. Aggregated statistics are shown for the following periods: **1 minute, 5 minutes, 30 minutes** and **60 minutes**. Currently, the table shows overall Near Cache effectiveness, calculated as hits/total reads ratio.\n\nYou need to enable the statistics for clients to see them here. Please refer to **Monitoring Clients** for details.\n\n<table>\n<thead>\n<tr>\n<th>Client Near Cache Summary</th>\n<th>Statistic</th>\n<th>1 minute</th>\n<th>5 Minutes</th>\n<th>30 minutes</th>\n<th>60 minutes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Effectiveness</td>\n<td>70 %</td>\n<td>68 %</td>\n<td>67 %</td>\n<td>N/A</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**Client Near Cache Data Table** provides information about the Near Caches statistics, if available, on each client that has Near Cache enabled for this map, as shown below.\n\nYou need to enable the statistics for clients to see them here. Please refer to **Monitoring Clients** for details.\nFrom left to right, this table lists the following:\n\n- **Client Name**: Name of the client instance which has Near Cache defined for the map.\n- **Client Type**: Type of the client.\n- **Client Version**: Version of the client.\n- **Client UUID**: Client unique identifier.\n- **Evictions**: Number of evictions of Near Cache entries owned by the client.\n- **Expirations**: Number of TTL and max-idle expirations of Near Cache entries owned by the client.\n- **Hits**: Number of hits (reads) of Near Cache entries owned by the client.\n- **Misses**: Number of misses of Near Cache entries owned by the client.\n- **Effectiveness**: Hits/total reads ratio.\n- **Owned Entry Count**: Number of Near Cache entries owned by the client.\n- **Owned Entry Memory Cost**: Memory cost of Near Cache entries owned by the client.\n\nTo ascend or descend the order of the listings, click on the column headings.\n\n### 13.2. Caches\n\nYou can see a list of all the caches in your cluster by clicking on the **Caches** menu item on the left panel. A new page is opened on the right, as shown below.\nYou can filter the caches shown and you can also sort the table by clicking on the column headers. Clicking on the cache name opens a new page for monitoring that cache instance on the right, as shown below.\n\n### Caches\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Entries</th>\n<th>Hits</th>\n<th>Misses</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>cache-42</td>\n<td>19</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-43</td>\n<td>17</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-44</td>\n<td>7</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-45</td>\n<td>18</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-46</td>\n<td>14</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-47</td>\n<td>12</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-48</td>\n<td>8</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-49</td>\n<td>31</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-5</td>\n<td>6</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-50</td>\n<td>15</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-51</td>\n<td>13</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-52</td>\n<td>24</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-53</td>\n<td>12</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-54</td>\n<td>8</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-55</td>\n<td>15</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-56</td>\n<td>29</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-57</td>\n<td>12</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-58</td>\n<td>6</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-59</td>\n<td>13</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>cache-6</td>\n<td>7</td>\n<td>0</td>\n<td>0</td>\n</tr>\n</tbody>\n</table>\n\nOn top of the page, four charts monitor the **Gets**, **Puts**, **Removals** and **Evictions** in real-time. The X-axis of all the charts show the current system time. To open a chart as a separate dialog, click on the button placed at the top right of each chart.\nUnder these charts are **Cache Statistics**, **Cache Throughput**, and **Client Near Cache** data tables.\n\n**Cache Statistics Data Table** provides the selected cache’s statistics distributed over the members, as shown below.\n\n<table>\n<thead>\n<tr>\n<th>Members</th>\n<th>Entries</th>\n<th>Gets</th>\n<th>Puts</th>\n<th>Removals</th>\n<th>Evictions</th>\n<th>Hits</th>\n<th>Misses</th>\n<th>Avg Get Time</th>\n<th>Avg Put Time</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>127.0.0.1:5701</td>\n<td>400</td>\n<td>3739</td>\n<td>9659</td>\n<td>235</td>\n<td>9022</td>\n<td>1660</td>\n<td>1879</td>\n<td>5.45ms</td>\n<td>35.57ms</td>\n</tr>\n<tr>\n<td>127.0.0.1:5702</td>\n<td>350</td>\n<td>3738</td>\n<td>9685</td>\n<td>222</td>\n<td>9064</td>\n<td>1646</td>\n<td>1860</td>\n<td>5.27ms</td>\n<td>26.28ms</td>\n</tr>\n<tr>\n<td>127.0.0.1:5703</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0.00ms</td>\n<td>0.00ms</td>\n</tr>\n<tr>\n<td>TOTAL</td>\n<td>750</td>\n<td>7477</td>\n<td>19343</td>\n<td>458</td>\n<td>18036</td>\n<td>3106</td>\n<td>3771</td>\n<td>-</td>\n<td>-</td>\n</tr>\n</tbody>\n</table>\n\nFrom left to right, this table lists the following in real time:\n\n- **Members**: IP address and port of the member.\n- **Entries**: Number of entries in this cache owned by the member.\n- **Gets/Puts/Removals**: Number of the get/put/remove operations for this cache received by the member.\n- **Hits**: Number of the reads performed for this cache’s entries.\n- **Misses**: Number of the entries which cannot be found in the cache when requested to read.\n- **Avg Get/Put Time**: Average elapsed time for the get and put operations for the cache on each member.\n\nTo ascend or descend the order of the listings, click on the column headings.\n\n**Cache Throughput Data Table** provides information about the operations (get, put, remove) performed on each member for the selected cache.\n\n<table>\n<thead>\n<tr>\n<th>Members</th>\n<th>Puts/s</th>\n<th>Gets/s</th>\n<th>Remover/s</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>127.0.0.1:5701</td>\n<td>0.20</td>\n<td>0.20</td>\n<td>0.20</td>\n</tr>\n<tr>\n<td>127.0.0.1:5702</td>\n<td>0.00</td>\n<td>0.00</td>\n<td>0.00</td>\n</tr>\n<tr>\n<td>127.0.0.1:5703</td>\n<td>0.20</td>\n<td>0.20</td>\n<td>0.20</td>\n</tr>\n</tbody>\n</table>\n\nFrom left to right, this table lists the following:\n\n- **IP address and port of each member**.\n- **Put, get and remove operation rates on each member for this cache**.\n\nYou can select the period in the combo box placed at the top right corner of the window, for which the table data will be shown. Available values are **Since Beginning**, **Last Minute**, **Last 10 Minutes** and **Last 1 Hour**.\n\nYou can ascend or descend the order of the listings in each column by clicking on column headings.\n\n**Client Near Cache Summary** provides summary information related to the Near Cache statistics aggregated for all the clients that have Near Cache enabled for this cache. Aggregated statistics are shown for the following periods: **1 minute, 5 minutes, 30 minutes and 60 minutes**. Currently, the table shows overall Near Cache effectiveness, calculated as hits/total reads ratio.\nYou need to enable the statistics for clients to see them here. Please refer to Monitoring Clients for details.\n\nClient Near Cache Data Table provides information about the Near Caches statistics, if available, on each client that has Near Cache enabled for this cache, as shown below.\n\nYou need to enable the statistics for clients to see them here. Please refer to Monitoring Clients for details.\n\nFrom left to right, this table lists the following:\n\n- **Client Name**: Name of the client instance which has Near Cache enabled for the map.\n- **Client Type**: Type of the client.\n- **Client Version**: Version of the client.\n- **Client UUID**: Client unique identifier.\n- **Evictions**: Number of evictions of Near Cache entries owned by the client.\n- **Expirations**: Number of TTL and max-idle expirations of Near Cache entries owned by the client.\n- **Hits**: Number of hits (reads) of Near Cache entries owned by the client.\n- **Misses**: Number of misses of Near Cache entries owned by the client.\n- **Effectiveness**: Hits/total reads ratio.\n- **Owned Entry Count**: Number of Near Cache entries owned by the client.\n- **Owned Entry Memory Cost**: Memory cost of Near Cache entries owned by the client.\n\nTo ascend or descend the order of the listings, click on the column headings.\n\nYou need to enable the statistics for caches to monitor them in the Management Center. Use the `<statistics-enabled>` element or `setStatisticsEnabled()` method in declarative or programmatic configuration, respectively, to enable the statistics. Please refer to the JCache Declarative Configuration section for more information.\n\n### 13.3. Replicated Maps\n\nYou can see a list of all the Replicated Maps in your cluster by clicking on the Replicated Maps menu item on the left panel. A new page is opened on the right, as shown below.\nYou can filter the Replicated Maps shown and you can also sort the table by clicking on the column headers. Clicking on a Replicated Map name opens a new page for monitoring that Replicated Map instance on the right, as shown below.\n\nIn this page, you can monitor metrics and also re-configure the selected Replicated Map. All of the statistics are real-time monitoring statistics.\n\nWhen you click on a desired monitoring, the chart is loaded with the selected option. Also you can open the chart in new window.\n\n- **Entries**: Monitors number of entries of the Replicated Map.\n- **Operations/s**: Monitors number of all operations performed on the Replicated Map per second.\n- **Memory**: Monitors memory usage of the Replicated Map.\n• **Hits**: Monitors hit count of the Replicated Map.\n\n• **Puts/s, Gets/s, Removes/s**: These three charts monitor the put, get and remove operations performed on the selected Replicated Map per second.\n\nUnder these charts are Replicated Map Statistics and Replicated Map Throughput data tables.\n\nReplicated Map Statistics Data Table provides statistics distributed over the members, as shown below.\n\nFrom left to right, this table lists the following:\n\n• **Members**: IP address and port of the member.\n\n• **Entries**: Number of entries in this Replicated Map owned by the member.\n\n• **Gets/Puts/Removals**: Number of the get/put/remove operations for this Replicated Map received by the member.\n\n• **Entry Memory**: Memory cost of the owned entries in the member.\n\n• **Events**: Number of the events received by the member.\n\n• **Hits**: Number of the reads performed for this Replicated Map's entries.\n\nReplicated Map Throughput Data Table provides information about operations (get, put, remove) performed on each member in the selected Replicated Map.\n\nFrom left to right, this table lists the following:\n\n• IP address and port of each member\n\n• put, get, and remove operations on each member\n\n• average put, get, and remove latencies\n\n• maximum put, get, and remove latencies on each member.\n\nYou can select the period from the combo box placed at the top right corner of the window, in which the table data is shown. Available values are Since Beginning, Last Minute, Last 10 Minutes and Last 1 Hour.\n\nTo ascend or descend the order of the listings, click on the column headings.\n13.4. MultiMaps\n\nYou can see a list of all the MultiMaps in your cluster by clicking on the MultiMaps menu item on the left panel. A new page is opened on the right, as shown below.\n\n```\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Entries</th>\n<th>Backups</th>\n<th>Events</th>\n<th>Hits</th>\n<th>Locks</th>\n<th>DirtyEntries</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Multi Map - 0</td>\n<td>4</td>\n<td>4</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>Multi Map - 1</td>\n<td>16</td>\n<td>16</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>Multi Map - 2</td>\n<td>9</td>\n<td>9</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>Multi Map - 3</td>\n<td>15</td>\n<td>14</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n<td>0</td>\n</tr>\n</tbody>\n</table>\n```\n\nYou can filter the MultiMaps shown and you can also sort the table by clicking on the column headers. Clicking on a MultiMap name opens a new page for monitoring that MultiMap instance on the right.\n\nMultiMap is a specialized map where you can associate a key with multiple values. This monitoring option is similar to the Maps option: the same monitoring charts and data tables monitor MultiMaps. The differences are that you cannot browse the MultiMaps and re-configure it. Please see the Managing Maps.\n\n13.5. Queues\n\nYou can see a list of all the queues in your cluster by clicking on the Queues menu item on the left panel. A new page is opened on the right, as shown below.\n\n```\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Items</th>\n<th>Backups</th>\n<th>Max age</th>\n<th>Min age</th>\n<th>Average age</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Queue - 0</td>\n<td>17</td>\n<td>17</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n<tr>\n<td>Queue - 1</td>\n<td>5</td>\n<td>5</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n<tr>\n<td>Queue - 2</td>\n<td>1</td>\n<td>1</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n<tr>\n<td>Queue - 3</td>\n<td>16</td>\n<td>16</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n<tr>\n<td>Queue - 4</td>\n<td>16</td>\n<td>16</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n<tr>\n<td>Queue - 5</td>\n<td>11</td>\n<td>11</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n<tr>\n<td>Queue - 6</td>\n<td>10</td>\n<td>10</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n<tr>\n<td>Queue - 7</td>\n<td>9</td>\n<td>9</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n<tr>\n<td>Queue - 8</td>\n<td>14</td>\n<td>13</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n<tr>\n<td>Queue - 9</td>\n<td>5</td>\n<td>0</td>\n<td>0s</td>\n<td>0s</td>\n<td>0s</td>\n</tr>\n</tbody>\n</table>\n```\n\nYou can filter the queues shown and you can also sort the table by clicking on the column headers. Clicking on a queue name opens a new page for monitoring that queue instance on the right, as shown below.\nOn top of the page, small charts monitor the size, offers and polls of the selected queue in real-time. The X-axis of all the charts shows the current system time. To open a chart as a separate dialog, click on the button placed at the top right of each chart. The monitoring charts below are available:\n\n- **Items**: Monitors the size of the queue. Y-axis is the entry count.\n- **Offers**: Monitors the offers sent to the selected queue. Y-axis is the offer count.\n- **Polls**: Monitors the polls sent to the selected queue. Y-axis is the poll count.\n\nUnder these charts are **Queue Statistics** and **Queue Operation Statistics** tables.\n\nQueue Statistics table provides item and backup item counts in the queue and age statistics of items and backup items at each member, as shown below.\n\nFrom left to right, this table lists the IP address and port, items and backup items on the queue of each member, and maximum, minimum and average age of items in the queue. The order of the listings in each column can be ascended or descended by clicking on the column headings.\n\nQueue Operation Statistics table provides information about the operations (offers, polls, events) performed on the queues, as shown below.\n\nFrom left to right, this table lists the IP address and port of each member, and counts of offers, rejected offers, polls, poll misses and events.\n\nYou can select the period in the combo box placed at the top right corner of the window to show the table data. Available values are **Since Beginning**, **Last Minute**, **Last 10 Minutes** and **Last 1 Hour**.\n\nClick on the column headings to ascend or descend the order of the listings.\n13.6. Topics\n\nYou can see a list of all the topics in your cluster by clicking on the Topics menu item on the left panel. A new page is opened on the right, as shown below.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Member</th>\n<th>Publishes</th>\n<th>Receives</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Topic - 0 (1)</td>\n<td>127.0.0.1:15706, 127.0.0.1:15705</td>\n<td>5</td>\n<td>0</td>\n</tr>\n<tr>\n<td>Topic - 1 (1)</td>\n<td>127.0.0.1:15706, 127.0.0.1:15705</td>\n<td>8</td>\n<td>0</td>\n</tr>\n<tr>\n<td>Topic - 2 (1)</td>\n<td>127.0.0.1:15706, 127.0.0.1:15705</td>\n<td>7</td>\n<td>0</td>\n</tr>\n<tr>\n<td>Topic - 3 (2)</td>\n<td>127.0.0.1:15706, 127.0.0.1:15705</td>\n<td>0</td>\n<td>0</td>\n</tr>\n<tr>\n<td>Topic - 4 (2)</td>\n<td>127.0.0.1:15706, 127.0.0.1:15705</td>\n<td>7</td>\n<td>0</td>\n</tr>\n<tr>\n<td>Topic - 5 (2)</td>\n<td>127.0.0.1:15706, 127.0.0.1:15705</td>\n<td>23</td>\n<td>0</td>\n</tr>\n<tr>\n<td>Topic - 6 (2)</td>\n<td>127.0.0.1:15706, 127.0.0.1:15705</td>\n<td>20</td>\n<td>0</td>\n</tr>\n</tbody>\n</table>\n\nYou can filter the topics shown and you can also sort the table by clicking on the column headers. Clicking on a topic name opens a new page for monitoring that topic instance on the right, as shown below.\n\nOn top of the page, two charts monitor the Publishes and Receives in real-time. They show the published and received message counts of the cluster, the members of which are subscribed to the selected topic. The X-axis of both charts show the current system time. To open a chart as a separate dialog, click on the button placed at the top right of each chart.\n\nUnder these charts is the Topic Operation Statistics table. From left to right, this table lists the IP addresses and ports of each member, and counts of the messages published and received per second in real-time. You can select the period in the combo box placed at top right corner of the table to show the table data. The available values are Since Beginning, Last Minute, Last 10 Minutes and Last 1 Hour.\n\nClick on the column heading to ascend or descend the order of the listings.\n\n13.7. Reliable Topics\n\nYou can see a list of all the Reliable Topics in your cluster by clicking on the Reliable Topics menu item on the left panel. A new page is opened on the right, as shown below.\nYou can filter the Reliable Topics shown and you can also sort the table by clicking on the column headers. Clicking on a Reliable Topic name opens a new page for monitoring that Reliable Topic instance on the right, as shown below.\n\nOn top of the page, two charts monitor the Publishes and Receives in real-time. They show the published and received message counts of the cluster, the members of which are subscribed to the selected reliable topic. The X-axis of both charts show the current system time. To open a chart as a separate dialog, click on the button placed at the top right of each chart.\n\nUnder these charts is the Reliable Topic Operation Statistics table. From left to right, this table lists the IP addresses and ports of each member, and counts of the messages published and received per second in real-time. You can select the period in the combo box placed at top right corner of the table to show the table data. The available values are Since Beginning, Last Minute, Last 10 Minutes and Last 1 Hour.\n\nClick on the column heading to ascend or descend the order of the listings.\n\n### 13.8. Executors\n\nYou can see a list of all the Executors in your cluster by clicking on the Executors menu item on the left panel. A new page is opened on the right, as shown below.\nYou can filter the Executors shown and you can also sort the table by clicking on the column headers. Clicking on an Executor name opens a new page for monitoring that Executor instance on the right, as shown below.\n\nOn top of the page, small charts monitor the pending, started, completed, etc. executors in real-time. The X-axis of all the charts shows the current system time. You can select other small monitoring charts using the button placed at the top right of each chart. Click the button to list the monitoring options, as shown below.\nWhen you click on a desired monitoring, the chart loads with the selected option. To open a chart as a separate dialog, click on the button placed at top right of each chart. The below monitoring charts are available:\n\n- **Pending**: Monitors the pending executors. Y-axis is the executor count.\n- **Started**: Monitors the started executors. Y-axis is the executor count.\n- **Start Lat. (msec.)**: Shows the latency when executors are started. Y-axis is the duration in milliseconds.\n- **Completed**: Monitors the completed executors. Y-axis is the executor count.\n- **Comp. Time (msec.)**: Shows the completion period of executors. Y-axis is the duration in milliseconds.\n\nUnder these charts is the **Executor Operation Statistics** table, as shown below.\n\nFrom left to right, this table lists the IP address and port of members, the counts of pending, started and completed executors per second, and the execution time and average start latency of executors on each member. Click on the column heading to ascend or descend the order of the listings.\n\n### 13.9. Locks\n\nYou can use the scripting feature of the Management Center to monitor the locks in your cluster. See the [Scripting section](#) to learn how to use this feature.\n\nYou can use the below scripts to retrieve various information about the locks in your cluster.\n\nTo find the number of active locks in your cluster, use the following script:\nTo print the locks in your cluster, use the following script:\n\n```javascript\nvar findLocks = function() {\n var lockStr = '';\n var distributedObjects = hazelcast.getDistributedObjects();\n for each(distributedObject in distributedObjects) {\n if(distributedObject.getServiceName().equals(\"hz:impl:lockService\")) {\n lockStr += distributedObject.getName() + '\n';\n }\n }\n return lockStr;\n}\nfindLocks();\n```\n\nTo force unlock a lock in your cluster, use the following script:\n\n```javascript\nvar forceUnlock = function(lockName) {\n hazelcast.getLock(lockName).forceUnlock();\n return 'OK';\n}\nforceUnlock('your_Lock_Name');\n```\n\nTo check if a lock is being hold by a member, use the following script:\nvar isLocked = function(lockName) {\n var locked = hazelcast.getLock(lockName).isLocked();\n return lockName + ' -> ' + locked;\n}\n\nisLocked('your_Lock_Name');\n\n13.10. PN Counters\n\nYou can see a list of all the PN counters in your cluster by clicking on the Counters menu item on the left panel. A new page is opened on the right, as shown below.\n\nYou can filter the counters shown and you can also sort the table by clicking on the column headers. The monitoring data available are:\n\n- **Increment Operations/s**: Average number of times the counter was incremented per second during the last timeslice.\n- **Decrement Operations/s**: Average number of times the counter was decremented per second during the last timeslice.\n- **Number of Replicas**: Number of member instances that have a state for the counter.\n\nClicking on a counter name opens a new page for monitoring that specific counter instance, as shown below.\nThe table can likewise be sorted by clicking the column headers. It shows IP and port of the members that have a state for the specific counter named in the page’s title. The monitoring data available are:\n\n- **Increment Operations/s**: Average number of times the counter was incremented on that member per second during the last timeslice\n- **Decrement Operations/s**: Average number of times the counter was decremented on that member per second during the last timeslice\n- **Value**: Current value of the counter on that member.\n\n### 13.11. Flake ID Generators\n\nYou can see a list of all Flake ID Generators in your cluster by clicking on the **ID Generators** menu item on the left panel. A new page is opened on the right, as shown below.\n\nYou can filter the generators shown and you can also sort the table by clicking on the column headers. The monitoring data available are:\n\n- **Avg. Batch Requests**: Average count of batch requests coming from all the members to a generator, i.e., total batch requests from all members to a generator divided by the member count for that generator.\n- **Avg. Batch Size**: Average size of the ID batches created by a generator, i.e., total number of IDs generated (the sum of IDs for all batches) for all members divided by the total count of batch\nrequests coming from all members.\n\nClicking on a generator name opens a new page for monitoring that specific generator instance, as shown below.\n\n![Monitoring Page Example]\n\nThe table can likewise be sorted by clicking the column headers. It shows IP and port of the members that have a state for the specific generator named in the page’s title. The monitoring data available are:\n\n- **Batch Requests**: Total count of batch requests to a generator by this member.\n- **Avg. Batch Size**: Average size of the ID batches created for this member, i.e., total number of IDs generated (the sum of IDs for all batches) for this member divided by the total count of batch requests coming from this member.\n\nThe operations per second is not the number of new IDs generated or used but the number of ID batches. The batch size is configurable, usually it contains hundreds or thousands of IDs. A client uses all IDs from a batch before a new batch is requested.\n\n14. Monitoring WAN Replication\n\nWAN replication schemes are listed under the **WAN Replication** menu item on the left. When you click on a scheme, a new page for monitoring the targets which that scheme has appears on the right, as shown below:\nIn this page, you see the **WAN Replication Operations Table** for each target which belongs to this scheme. One of the example tables is shown below:\n\n- **Connected**: Status of the member connection to the target.\n- **Events Published per Second**: Number of published events per second. Please see the paragraph below.\n- **Average Event Latency**: Average latency of sending a record to the target from this member. Please see the paragraph below.\n- **Outbound Queue Size**: Number of records waiting in the queue to be sent to the target.\n- **Action**: Pause, stop or resume replication of a member’s records. You can also clear the event queues in a member using the \"Clear Queues\" action. For instance, if you know that the target cluster is being shut down, decommissioned, put out of use and it will never come back, you may additionally clear the WAN queues to release the consumed heap after the publisher has been switched. Or, when a failure happens and queues are not replicated anymore, you could manually clear the queues using, again the “Clear Queues” action.\n- **State**: Shows current state of the WAN publisher on a member. See Changing WAN Publisher State for the list of possible WAN publisher states.\n\n**Events Published per Second** and **Average Event Latency** are based on the following internal statistics:\n\n- Total published event count (TBEC): Total number of events that are successfully sent to the target cluster since the start-up of the member.\n• Total latency (TL): Grand total of each event's waiting time in the queue, including network transmit and receiving ACK from the target.\n\nEach member sends these two statistics to the Management Center at intervals of 3 seconds (update interval). Management Center derives **Events Published per Second** and **Average Event Latency** from these statistics as formulated below:\n\nEvents Published per Second = (Current TBEC - Previous TBEC) / Update Interval\n\nAverage Event Latency = (Current TL - Previous TL) / (Current TBEC - Previous TBEC)\n\n### 14.1. Changing WAN Publisher State\n\nA WAN publisher can be in one of the following states:\n\n- **REPLICATING** (default): State where both enqueuing new events is allowed, enqueued events are replicated to the target cluster.\n- **PAUSED**: State where new events are enqueued but they are not dequeued. Some events which have been dequeued before the state was switched may still be replicated to the target cluster but further events will not be replicated.\n- **STOPPED**: State where neither new events are enqueued nor dequeued. As with the **PAUSED** state, some events might still be replicated after the publisher has switched to this state.\n\nYou can change a WAN publisher's state by clicking the **Change State** dropdown button on top right hand corner of the WAN Replication Operations Table.\n\n### 14.2. WAN Sync\n\nYou can initiate a synchronization operation on an IMap for a specific target cluster. This operation is useful if two remote clusters lost their synchronization due to WAN queue overflow or in restart scenarios.\n\nHazelcast provides the following synchronization options:\n\n1. Default WAN synchronization operation: It sends all the data of an IMap to a target cluster to align the state of target IMap with the source IMap. See [here](#) for more information.\n\n2. WAN synchronization using **Merkle trees**: To initiate this type of synchronization, you need to configure the cluster members. See the **Delta WAN Synchronization section** in Hazelcast IMDG Reference Manual for details about configuring them. Make sure you meet all the requirements to use Delta WAN Synchronization and do the configuration on both the source and target clusters.\nTo initiate WAN Sync, open the **WAN Replication** menu item on the left and navigate to the **Sync** tab.\n\nClick **Start** button to open the dialog, enter the target details for the sync operation and click **Sync** to start the operation.\n\nYou can also use the \"All Maps\" option in the above dialog if you want to synchronize all the maps in source and target cluster.\n\nYou can see the progress of the operation once you initiate it.\n14.3. WAN Consistency Check\n\nYou can check if an IMap is in sync with a specific target cluster. Click Check button to open the dialog, enter the target details for the consistency check operation and click Check Consistency to start the operation.\n\nYou can see the progress of the operation once you initiate it.\nYou need to use Merkle trees for WAN synchronization to be able to check for the consistency between two clusters. You need to configure the Merkle trees on both the source and target clusters. If you do not configure it for the source cluster, consistency check is ignored. If it’s enabled for the source cluster but not for the target cluster, all entries are reported as if they need a sync because a sync operation will be a full sync in the absence of Merkle trees.\n\n14.4. Add Temporary WAN Replication Configuration\n\nYou can add a temporary WAN replication configuration dynamically to a cluster. It is useful for having one-off WAN sync operations. The added configuration has two caveats:\n\n- It is not persistent, so it does not survive a member restart.\n- It cannot be used as a target for regular WAN replication. It can only be used for WAN sync.\nSee the **WAN Replication section** in Hazelcast IMDG Reference Manual for details about the fields and their possible values.\n\nAfter clicking the **Add Configuration** button, the new WAN replication configuration is added to the cluster. You can see the new configuration when you try to initiate a WAN sync operation as described in the previous section.\n\n## 15. Scripting\n\nYou can use the scripting feature of the Management Center to execute scripts on the cluster. Note that it’s disabled by default and you need to enable it in your cluster’s configuration. Please see the **Toggle Scripting Support section** in the Hazelcast IMDG Reference Manual for details. Members list shows whether scripting is enabled or disabled for each member.\n\nTo use this feature, click on the **Scripting** menu item on the left panel. Once selected, the scripting feature opens as shown below.\nIn this window, the left panel is the actual script code editor. The combo box located at the top part of the editor enables you to select a scripting language: currently, JavaScript, Ruby, Groovy and Python languages are supported. You can select the members on which the code will execute from the **Members** list shown at the right side of the window. After you write your script and press the **Execute** button, you can see the execution result in the **Result** part of the window.\n\nTo use the scripting languages other than JavaScript on a member, the libraries for those languages should be placed in the classpath of that member. See the **Enabling Additional Scripting Languages section** for more details.\n\nThere are **Save** and **Delete** buttons on the top right of the scripting editor. To save your scripts, press the **Save** button after you type a name for your script into the field next to this button. The scripts you saved are listed in the **Saved Scripts** part of the window, located at the bottom right of the page. Click on a saved script from this list to execute or edit it. If you want to remove a script that you wrote and saved before, select it from this list and press the **Delete** button.\n\nIn the scripting engine you have a **HazelcastInstance** bonded to a variable named **hazelcast**. You can invoke any method that **HazelcastInstance** has via the **hazelcast** variable. You can see an example usage for JavaScript below:\n\n```javascript\nvar name = hazelcast.getName();\nvar node = hazelcast.getCluster().getLocalMember();\nvar employees = hazelcast.getMap(\"employees\");\nemployees.put(\"1\",\"John Doe\");\nemployees.get(\"1\"); // will return \"John Doe\"\n```\n### 15.1. Enabling Additional Scripting Languages\n\nIMDG members use the `javax.script.ScriptEngineManager` API for the execution of the script. Only the JavaScript script engine is available in most JVMs by default. To use a scripting language other than JavaScript on a member, you need to add the corresponding scripting engine in the classpath of that member. Here is an example of Maven configuration for several scripting engines:\n\n```xml\n<dependencies>\n <!-- Groovy -->\n <dependency>\n <groupId>org.codehaus.groovy</groupId>\n <artifactId>groovy-jsr223</artifactId>\n <version>2.5.6</version>\n </dependency>\n\n <!-- Ruby (JRuby) -->\n <dependency>\n <groupId>org.mule.modules</groupId>\n <artifactId>mule-module-scripting-jruby</artifactId>\n <version>3.9.0</version>\n </dependency>\n\n <!-- Joda-Time -->\n <dependency>\n <groupId>joda-time</groupId>\n <artifactId>joda-time</artifactId>\n <version>2.10.2</version>\n </dependency>\n\n <!-- Python (Jython) -->\n <dependency>\n <groupId>org.python</groupId>\n <artifactId>jython-standalone</artifactId>\n <version>2.7.1</version>\n </dependency>\n</dependencies>\n```\n\n### 16. Executing Console Commands\n\nThe Management Center has a console feature that enables you to execute commands on the cluster. For example, you can perform `puts` and `gets` on a map, after you set the namespace with the command `ns <name of your map>`. The same is valid for queues, topics and other data structures that can be monitored on the Management Center. To execute your command, type it into the field below the console and press Enter. Type `help` to see all the commands that you can use.\n\nOpen a console window by clicking on the Console button located on the left panel or the one located at the top menu. You can also open it by using `ALT + T` keyboard shortcut on Windows/Linux and `Option + T` on macOS. Below is a sample view with the `help` command executed.\nThe Management Center sends commands to one of the cluster members; for this, it makes an HTTP request to the REST endpoint on that member. As you can see in the above screenshot, the console screen shows the IP address of the member which receives the console commands. Basically, it connects to the port that member listens to, which is configured on the member side as described here. An example configuration on the member side is shown below:\n\n```xml\n<hazelcast>\n ...\n <network>\n <port port-count=\"20\" auto-increment=\"true\">5701</port>\n </network>\n ...\n</hazelcast>\n```\n\nThe direction of this communication is from an ephemeral port number on the Management Center to the port number 5701 (according to the above example) on the member.\n\nThere is no configuration option to specify which outbound ports the Management Center will use; it picks on from the ephemeral port pool. Note that, this can create an issue where a firewall is placed between the cluster and Management Center.\n\n17. Cluster Administration\n\nUsing the \"Administration\" menu item, you can change the state of your cluster, shut down it, update your Management Center license and perform Rolling Upgrade or Hot Restart on your cluster.\n\nWhen you click on the \"Administration\" menu item, the following page shows up:\nThis menu item is available only to admin users.\n\nYou can perform the aforementioned administrative tasks using the tabs on this page. Below sections explain each tab.\n\n### 17.1. Cluster State\n\nThe admin user can see and change the cluster state and shut down the cluster using the buttons listed in this page as shown below.\n\n#### Cluster States:\n\n- **Active**: The cluster continues to operate without any restriction. All operations are allowed. This is the default state of a cluster.\n\n- **No Migration**: Migrations (partition rebalancing) and backup replications are not allowed. The cluster continues to operate without any restriction. All other operations are allowed.\n\n- **Frozen**: New members are not allowed to join, except the members left in this or the Passive state. All other operations except migrations are allowed and the cluster operates without any restriction.\n\n- **Passive**: New members are not allowed to join, except the members left in this or the Frozen state. All operations, except the ones marked with `AllowedDuringPassiveState`, are rejected immediately.\n\n- **In Transition**: Shows that the cluster state is in transition. This is a temporary and intermediate state. It is not allowed to set it explicitly.\n\n#### Changing the Cluster State\nCluster State\n\nCluster Name: dev\nCurrent Cluster State: Active\nChange Cluster State:\n - Active\n - Frozen\n - Passive\n - No Migration\nShut down Cluster:\n\n- Click the dropdown menu and choose the state to which you want your cluster to change. A pop-up appears and stays on the screen until the state is successfully changed.\n\nShutting Down the Cluster\n\n- Click the Shutdown button. A pop-up appears and stays on the screen until the cluster is\nIf an exception occurs during the state change or shutdown operation on the cluster, this exception message is shown on the screen as a notification.\n\n17.2. Rolling Upgrade\n\nThe admin user can upgrade the cluster version once all members of the cluster have been upgraded to the intended codebase version as described in the Rolling Upgrade Procedure section of the Hazelcast IMDG Reference Manual.\n\nOpen the **Rolling Upgrade** tab to perform a Rolling Upgrade and change the cluster's version.\n\nEnter the password of the cluster if security is enabled on the cluster (leave it empty if not), and click on the **Change Version** button.\n\nOnce the operation succeeds, you will see the following notification:\n17.3. Hot Restart\n\nUsing the Hot Restart tab, you can perform force and partial start of the cluster and see the Hot Restart status of the cluster members. You can also take snapshots of the Hot Restart Store (Hot Backup). When you click on this tab, the following page is shown:\n\n![Hot Restart Page]\n\nBelow sections explain each operation.\n\n17.3.1. Force Start\n\nRestart process cannot be completed if a member crashes permanently and cannot recover from the failure since it cannot start or it fails to load its own data. In that case, you can force the cluster to clean its persisted data and make a fresh start. This process is called **force start**.\n\nSee the Force Start section in the Hazelcast IMDG Reference Manual for more information on this operation.\n\nTo perform a force start on the cluster, click on the Force Start button. A confirmation dialog appears as shown below.\nOnce you click on the **Force Start** button on this dialog, the cluster starts the force start process and the following progress dialog shows up while doing so.\n\nThis dialog stays on the screen until the operation is triggered. Once it is done, the success of force start operation is shown as a notice dialog, as shown below.\n\nIf an exception occurs, this exception message is shown on the screen as a notification.\n\n### 17.3.2. Partial Start\n\nWhen one or more members fail to start or have incorrect Hot Restart data (stale or corrupted data) or fail to load their Hot Restart data, the cluster becomes incomplete and the restart mechanism cannot proceed. One solution is to use Force Start and make a fresh start with the existing...\nmembers, as explained above. Another solution is to do a partial start.\n\nPartial start means that the cluster will start with an incomplete set of members. Data belonging to the missing members is assumed lost and the Management Center tries to recover the missing data using the restored backups. For example, if you have minimum two backups configured for all the maps and caches, then a partial start up to two missing members is safe against data loss. If there are more than two missing members or there are maps/caches with less than two backups, then data loss is expected.\n\nSee the Partial Start section in the Hazelcast IMDG Reference Manual for more information on this operation and how to enable it.\n\nTo perform a partial start on the cluster, click on the Partial Start button. A notice dialog appears as shown below.\n\nYou can also see two fields related to Partial Start operation: \"Remaining Data Load Time\" and \"Remaining Validation Time\", as shown in the above screenshot.\n\n- **Remaining Validation Time**: When partial start is enabled, Hazelcast can perform a partial start automatically or manually, in case of some members are unable to restart successfully. Partial start proceeds automatically when some members fail to start and join to the cluster in validation-timeout-seconds, which you can configure. After this duration is passed, Hot Restart chooses to perform a partial start with the members present in the cluster. This field, i.e., \"Remaining Validation Time\" shows how much time is left to the automatic partial start, in seconds. You can always request a manual partial start, by clicking on the Partial Start button, before this duration passes.\n\n- **Remaining Data Load Time**: The other situation to decide to perform a partial start is the failures during the data loading phase. When Hazelcast learns the data loading result of all members which have passed the validation step, it automatically performs a partial start with the ones which have successfully restored their Hot Restart data. Note that partial start does not expect every member to succeed in the data loading step. It completes the process when it learns the data loading result for every member and there is at least one member which has successfully restored its Hot Restart data. Relatedly, if it cannot learn the data loading result of all members before data-load-timeout-seconds duration, it proceeds with the ones which have already completed the data loading process. This field, i.e., \"Remaining Data Load Time\" shows how much time (in seconds) is left for Hazelcast to know at least one member has successfully restored its Hot Restart data and perform an automatic partial start.\nSee the Configuring Hot Restart section in the Hazelcast IMDG Reference Manual for more information on the configuration elements `validation-timeout-seconds` and `data-load-timeout-seconds` mentioned above and how to configure them.\n\nForce and partial start operations can also be performed using the REST API and the script `cluster.sh`. See the Using REST API for Cluster Management section and Using the Script `cluster.sh` section in the Hazelcast IMDG Reference Manual.\n\n### 17.3.3. Hot Backup\n\nDuring Hot Restart operations, you can take a snapshot of the Hot Restart data at a certain point in time. This is useful when you wish to bring up a new cluster with the same data or parts of the data. The new cluster can then be used to share load with the original cluster, to perform testing, quality assurance or reproduce an issue on the production data.\n\nNote that you must first configure the Hot Backup directory programmatically (using the method `setBackupDir()`) or declaratively (using the element `backup-dir`) to be able to take a backup of the Hot Restart data. See the Configuring Hot Backup section in the Hazelcast IMDG Reference Manual.\n\nIf the backup directory is configured, you can start to perform the backup by clicking on the **Hot Backup** button. The Management Center first asks the cluster password as shown in the following dialog.\n\n\n\nOnce you entered the password correctly and click on the \"Start\" button on this dialog, you will see a notification dialog stating that the backup process starts. You can see the progress of the backup operation under the \"Last Hot Backup Task Status\" part of the page, as shown below.\n17.3.4. Status Information\n\nAt the bottom of \"Hot Restart\" tab, you can see the Hot Restart and Hot Backup statuses of cluster members, as shown below.\n\nYou can see the status and progress of your Hot Backup operation under \"Last Hot Backup Task Status\". It can be IN_PROGRESS and SUCCESS/FAILURE according to the result of the operation.\n\nYou can also see the status of Hot Restart operation of your cluster members, under \"Hot Restart Status\". It can be PENDING and SUCCESSFUL/FAILED according to the result of Hot Restart\n17.4. CP Subsystem\n\nCP subsystem management operations require enabled REST API in the IMDG cluster. See the IMDG documentation for more information.\n\nThe CP Subsystem tab can be used to monitor overall status of the CP subsystem in the current cluster and perform certain management operations.\n\n17.4.1. Monitoring CP Subsystem\n\nThe Status field shows a summary of the current CP subsystem status. It may have one of the following values:\n\n- **CP Subsystem is not supported by this cluster**: Shown for IMDG clusters with version prior to 3.12.\n- **CP Subsystem is not enabled**: Shown if CP subsystem is not enabled for the current cluster.\n- **All CP members are accessible**: Shown if there are at least the same amount of accessible CP members as the configured CP member count.\n- **CP Subsystem warning: one CP member is not accessible**: Shown if there is one missing CP member and the minority count in the CP subsystem is greater than 1. For example, this value is shown when there are 6 accessible CP members and the configured count is 7. In this example, the minority count is 3 members and the majority count is 4 members.\n- **CP Subsystem alert: multiple CP members are not accessible**: Shown if there are multiple missing CP members, but their count is less than the minority.\n- **CP Subsystem error: minority of the CP members are not accessible**: Shown if the minority of CP members are missing.\n- **CP Subsystem error: majority of the CP members are not accessible**: Shown if the majority of CP members are missing.\n\nThe CP Members (Accessible/Configured) field shows the current count of accessible CP members and the configured CP members count.\nYou may promote additional members or remove inaccessible CP members, so the total count of members that participate in the CP subsystem may be greater or less than the configured CP member count. As the Status field considers the configured CP member count as the total CP member count, it should be treated only as a basic health indicator for the CP subsystem.\n\n### 17.4.2. Managing CP Subsystem\n\nYou can also use the CP Subsystem tab to start the following management operations.\n\n**Promote Member to CP Subsystem**\n\nTo promote one of the AP members to become a CP member, click on the Promote button. A confirmation dialog appears as shown below.\n\n![Promote Member to CP dialog]\n\nIt asks you to choose one of AP members, i.e., one of the members that do not participate in the CP subsystem. Note that lite members are not shown in the dropdown list as lite members do not store data. Once you press the Promote button, the CP subsystem starts the promote operation for the given member.\n\n**Remove CP Member**\n\nTo remove one of the inaccessible CP members from the CP subsystem, click on the Remove button. A confirmation dialog appears as shown below.\n\n![Remove CP Member dialog]\n\nIt asks you to choose one of the members that is not connected to the Management Center, but is\nknown by the cluster's CP subsystem. Once you press the **Remove** button, the CP subsystem starts the remote operation for the given member.\n\n**Restart CP Subsystem**\n\nTo wipe and restart the whole CP subsystem of the cluster, click on the **Restart** button. A confirmation dialog appears as shown below.\n\nOnce you press the **Restart** button, CP subsystem proceeds with the restart operation.\n\nThe CP subsystem restart operation is **NOT** idempotent and multiple invocations can break the whole system! After using this dialog, you must observe the system to see if the restart process is successfully completed or failed before starting this operation again.\n\n**18. Using Time Travel**\n\nUse the **Time Travel** toolbar item to check the status of the cluster at a time in the past. When you select it on the toolbar, a small window appears on top of the page, as shown below:\n\nTo see the cluster status in a past time, you should first enable the time travel. Turn on the switch with the \"Time Travel\" label. It changes to **ON** after it asks whether to enable the time travel with a dialog. Click on **Enable** in the dialog to enable it.\n\nOnce it is **ON**, the status of your cluster will be stored on your disk as long as your web server is alive.\n\nUnless you turn on the switch with the \"Travel to chosen timestamp\" label, you will continue seeing the latest data. When you turn the switch on, you can go back in time using the calendar and check\nyour cluster's situation at the selected time. All the data structures and members can be monitored as if you are using the Management Center normally (charts and data tables for each data structure and members). It shows the status if time travel has been ON at the selected time in past; otherwise, all the charts and tables are shown as empty.\n\nIn the \"Travel to chosen timestamp\" mode, the graphs do not refresh continuously. You will see data for the selected time. You can press the blue button next to the calendar to see the latest data. Note that this will only show you the latest data and not cause the charts and data tables refresh with latest data continuously. For that, you need to turn off the switch with the \"Travel to chosen timestamp\" label.\n\nThe historical data collected with the time travel feature is stored in a file database on the disk. The data files can be found in the <User's Home Directory>/hazelcast-mc directory, e.g., /home/someuser/hazelcast-mc. This directory can be changed using the hazelcast.mc.home property on the server where the Management Center is running.\n\nTime travel data files are created monthly. Their file name format is [cluster-name]-[year][month].db and [cluster-name]-[year][month].lg. Time travel data is kept in the *.db files. The files with the extension lg are temporary files created internally and you do not have to worry about them.\n\nDue to security concerns, time travel can only be used if the cluster name consists of alphanumeric characters, underscores and dashes.\n\n19. Clustered REST\n\nHazelcast IMDG Enterprise\n\nThe Clustered REST API is exposed from the Management Center to allow you to monitor clustered statistics of distributed objects.\n\n19.1. Enabling Clustered REST\n\nTo enable Clustered REST on your Management Center, pass the following system property at startup. This property is disabled by default.\n\n-Dhazelcast.mc.rest.enabled=true\n\n19.2. Clustered REST API Root\n\nThe entry point for the Clustered REST API is /rest/. This resource does not have any attributes.\nAll parameters that are used in the REST API URLs, like cluster names and distributed data structure names, must be URL encoded when composing a valid request for Clustered REST. Such parameters are marked in braces ({} and {}) in the URL description for each endpoint. As an example, name.with/special@chars parameter value would be encoded as name.with%2Fspecial%40chars.\n\nAll endpoints return HTTP status code 404 if no data about a cluster, member, client or data structure can be found in the Management Center.\n\n19.2.1. Retrieve Management Center License Expiration Time\n\nThis endpoint returns the expiration time in milliseconds (since epoch) of the license key assigned for the Management Center. Returns -1 if no license is assigned.\n\n- **Request Type**: GET\n- **URL**: /rest/license\n- **Request**:\n \n curl http://localhost:8080/rest/license\n\n- **Response**: 200 (application/json)\n- **Body**:\n\n ```json\n {\n \"licenseExpirationTime\": 4099755599515\n }\n ```\n\n19.3. Clusters Resource\n\nThis resource returns a list of clusters that are connected to the Management Center.\n\n19.3.1. Retrieve Clusters\n\n- **Request Type**: GET\n- **URL**: /rest/clusters\n- **Request**:\n \n curl http://localhost:8080/rest/clusters\n\n- **Response**: 200 (application/json)\n- **Body**:\n19.4. Cluster Resource\n\nThis resource returns information related to the provided cluster name.\n\n19.4.1. Retrieve Cluster Information\n\nThis endpoint returns address of the oldest cluster member and the expiration time in milliseconds (since epoch) of the license key assigned for the cluster. Returns -1 for license expiration time if no license is assigned.\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}\n- **Request:**\n\n ```\n curl http://localhost:8080/rest/clusters/dev/\n ```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n ```\n {\n \"masterAddress\": \"192.168.2.78:5701\",\n \"licenseExpirationTime\": 409975599515\n }\n ```\n\n19.5. Members Resource\n\nThis resource returns a list of the members belonging to the provided clusters.\n\n19.5.1. Retrieve Members [GET] [/rest/clusters/{clustername}/members]\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/members\n- **Request:**\n\n ```\n curl http://localhost:8080/rest/clusters/dev/members\n ```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n ```\n 101\n ```\n19.6. Member Resource\n\nThis resource returns information related to the provided member.\n\n19.6.1. Retrieve Member Information\n\n- **Request Type:** GET\n- **URL:** `/rest/clusters/{clustername}/members/{member}`\n- **Request:**\n\n ```\ncurl http://localhost:8080/rest/clusters/dev/members/192.168.2.78:5701\n ```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n ```\n {\n \"cluster\": \"dev\",\n \"name\": \"192.168.2.78:5701\",\n \"uuid\": \"11adba52-e19d-4407-a9e9-e0a271cef14a\",\n \"cpMemberUuid\": \"f5a8f8a4-f278-4a13-a23e-5accf5b02f42\",\n \"maxMemory\": 129957888,\n \"ownedPartitionCount\": 68,\n \"usedMemory\": 60688784,\n \"freeMemory\": 24311408,\n \"totalMemory\": 85000192,\n \"connectedClientCount\": 1,\n \"master\": true\n }\n ```\n\n19.6.2. Retrieve Connection Manager Information\n\n- **Request Type:** GET\n- **URL:** `/rest/clusters/{clustername}/members/{member}/connectionManager`\n- **Request:**\n• **Response:** 200 (application/json)\n\n• **Body:**\n\n```json\n{\n \"clientConnectionCount\": 2,\n \"activeConnectionCount\": 5,\n \"connectionCount\": 5\n}\n```\n\n### 19.6.3. Retrieve Operation Service Information\n\n• **Request Type:** GET\n\n• **URL:** `/rest/clusters/{clustername}/members/{member}/operationService`\n\n• **Request:**\n\n```\ncurl http://localhost:8080/rest/clusters/dev/members/192.168.2.78:5701/operationService\n```\n\n• **Response:** 200 (application/json)\n\n• **Body:**\n\n```json\n{\n \"responseQueueSize\": 0,\n \"operationExecutorQueueSize\": 0,\n \"runningOperationsCount\": 0,\n \"remoteOperationCount\": 1,\n \"executedOperationCount\": 461139,\n \"operationThreadCount\": 8\n}\n```\n\n### 19.6.4. Retrieve Event Service Information\n\n• **Request Type:** GET\n\n• **URL:** `/rest/clusters/{clustername}/members/{member}/eventService`\n\n• **Request:**\n\n```\ncurl http://localhost:8080/rest/clusters/dev/members/192.168.2.78:5701/eventService\n```\n• **Response**: 200 (application/json)\n\n• **Body**:\n\n```json\n{\n \"eventThreadCount\": 5,\n \"eventQueueCapacity\": 1000000,\n \"eventQueueSize\": 0\n}\n```\n\n### 19.6.5. Retrieve Partition Service Information\n\n• **Request Type**: GET\n\n• **URL**: `/rest/clusters/{clustername}/members/{member}/partitionService`\n\n• **Request**:\n\n```bash\ncurl http://localhost:8080/rest/clusters/dev/members/192.168.2.78:5701/partitionService\n```\n\n• **Response**: 200 (application/json)\n\n• **Body**:\n\n```json\n{\n \"partitionCount\": 271,\n \"activePartitionCount\": 68\n}\n```\n\n### 19.6.6. Retrieve Proxy Service Information\n\n• **Request Type**: GET\n\n• **URL**: `/rest/clusters/{clustername}/members/{member}/proxyService`\n\n• **Request**:\n\n```bash\ncurl http://localhost:8080/rest/clusters/dev/members/192.168.2.78:5701/proxyService\n```\n\n• **Response**: 200 (application/json)\n\n• **Body**:\n\n```json\n{\n \"proxyCount\": 8\n}\n```\n19.6.7. Retrieve All Managed Executors\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/members/{member}/managedExecutors\n- **Request:**\n\n ```\ncurl http://localhost:8080/rest/clusters/dev/members/192.168.2.78:5701/managedExecutors\n ```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n ```\n ```\n\n19.6.8. Retrieve a Managed Executor\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/members/{member}/managedExecutors/{managedExecutor}\n- **Request:**\n\n ```\n ```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n ```\n {\n \"name\": \"hz:system\",\n \"queueSize\": 0,\n \"poolSize\": 0,\n \"remainingQueueCapacity\": 2147483647,\n \"maximumPoolSize\": 4,\n \"completedTaskCount\": 12,\n \"terminated\": false\n }\n ```\n\n19.7. Client Endpoints Resource\n\nThis resource returns a list of the client endpoints belonging to the provided cluster. Consider using the newly added Client Statistics Resource as it contains more detailed information about the clients.\n19.7.1. Retrieve List of Client Endpoints\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/clients\n- **Request:**\n \n ```\ncurl http://localhost:8080/rest/clusters/dev/clients\n ```\n- **Response:** 200 (application/json)\n- **Body:**\n \n ```json\n [\"192.168.2.78:61708\"]\n ```\n\n19.7.2. Retrieve Client Endpoint Information\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/clients/{client}\n- **Request:**\n \n ```\ncurl http://localhost:8080/rest/clusters/dev/clients/192.168.2.78:61708\n ```\n- **Response:** 200 (application/json)\n- **Body:**\n \n ```json\n {\n \"uuid\": \"6fae7af6-7a7c-4fa5-b165-cde24cf070f5\",\n \"address\": \"192.168.2.78:61708\",\n \"clientType\": \"JAVA\",\n \"name\": \"hz.client_1\",\n \"labels\": [\n \"label1\"\n ],\n \"ipAddress\": \"192.168.2.78\",\n \"canonicalHostName\": \"localhost\"\n }\n ```\n\n19.8. Maps Resource\n\nThis resource returns a list of maps belonging to the provided cluster.\n19.8.1. Retrieve List of Maps\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/maps\n- **Request:**\n ```\ncurl http://localhost:8080/rest/clusters/dev/maps\n ```\n- **Response:** 200 (application/json)\n- **Body:**\n ```\n [\"customers\", \"orders\"]\n ```\n\n19.8.2. Retrieve Map Information\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/maps/{mapName}\n- **Request:**\n ```\ncurl http://localhost:8080/rest/clusters/dev/maps/customers\n ```\n- **Response:** 200 (application/json)\n- **Body:**\n19.9. MultiMaps Resource\n\nThis resource returns a list of multimaps belonging to the provided cluster.\n\n19.9.1. Retrieve List of MultiMaps\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/multimaps\n- **Request:**\n \n ```\ncurl http://localhost:8080/rest/clusters/dev/multimaps\n ```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n ```json\n \"customerAddresses\"\n ```\n19.9.2. Retrieve MultiMap Information\n\n- **Request Type**: GET\n- **URL**: /rest/clusters/{clustername}/multimaps/{multimapname}\n- **Request**:\n\n ```\n curl http://localhost:8080/rest/clusters/dev/multimaps/customerAddresses\n ```\n\n- **Response**: 200 (application/json)\n- **Body**:\n\n ```\n {\n \"cluster\": \"dev\",\n \"name\": \"customerAddresses\",\n \"ownedEntryCount\": 4862,\n \"backupEntryCount\": 4860,\n \"ownedEntryMemoryCost\": 0,\n \"backupEntryMemoryCost\": 0,\n \"heapCost\": 0,\n \"lockedEntryCount\": 1,\n \"dirtyEntryCount\": 0,\n \"hits\": 22,\n \"lastAccessTime\": 1532689253314,\n \"lastUpdateTime\": 1532689252591,\n \"creationTime\": 1532688790593,\n \"putOperationCount\": 5125,\n \"getOperationCount\": 931,\n \"removeOperationCount\": 216,\n \"otherOperationCount\": 373570,\n \"events\": 0,\n \"maxPutLatency\": 8,\n \"maxGetLatency\": 1,\n \"maxRemoveLatency\": 18001,\n \"averagePutLatency\": 0.3758048780487805,\n \"averageGetLatency\": 0.11170784103114931,\n \"averageRemoveLatency\": 1638.8472222222222\n }\n ```\n\n19.10. ReplicatedMaps Resource\n\nThis resource returns a list of replicated maps belonging to the provided cluster.\n\n19.10.1. Retrieve List of ReplicatedMaps\n\n- **Request Type**: GET\n19.10.2. Retrieve ReplicatedMap Information\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/replicatedmaps/{replicatedmapname}\n- **Request:**\n\n```bash\ncurl http://localhost:8080/rest/clusters/dev/replicatedmaps/replicated-map-1\n```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n```json\n{\n \"cluster\": \"dev\",\n \"name\": \"replicated-map-1\",\n \"ownedEntryCount\": 10955,\n \"ownedEntryMemoryCost\": 394380,\n \"hits\": 15,\n \"lastAccessTime\": 1532689312581,\n \"lastUpdateTime\": 1532689312581,\n \"creationTime\": 1532688789493,\n \"putOperationCount\": 11561,\n \"getOperationCount\": 1051,\n \"removeOperationCount\": 522,\n \"otherOperationCount\": 355552,\n \"events\": 6024,\n \"maxPutLatency\": 1,\n \"maxGetLatency\": 1,\n \"maxRemoveLatency\": 1,\n \"averagePutLatency\": 0.006400830377994983,\n \"averageGetLatency\": 0.012369172216936251,\n \"averageRemoveLatency\": 0.01149425287356218\n}\n```\n19.11. Queues Resource\n\nThis resource returns a list of queues belonging to the provided cluster.\n\n19.11.1. Retrieve List of Queues\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/queues\n- **Request:**\n \n curl http://localhost:8080/rest/clusters/dev/queues\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n ```json\n [ \"messages\"]\n ```\n\n19.11.2. Retrieve Queue Information\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/queues/{queueName}\n- **Request:**\n \n curl http://localhost:8080/rest/clusters/dev/queues/messages\n\n- **Response:** 200 (application/json)\n- **Body:**\n19.12. Topics Resource\n\nThis resource returns a list of topics belonging to the provided cluster.\n\n19.12.1. Retrieve List of Topics\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/topics\n- **Request:**\n \n```bash\ncurl http://localhost:8080/rest/clusters/dev/topics\n```\n \n- **Response:** 200 (application/json)\n- **Body:**\n\n ```json\n [ \"news\" ]\n ```\n\n19.12.2. Retrieve Topic Information\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/topics/{topicName}\n- **Request:**\n \n```bash\ncurl http://localhost:8080/rest/clusters/dev/topics/news\n```\n19.13. Executors Resource\n\nThis resource returns a list of executors belonging to the provided cluster.\n\n19.13.1. Retrieve List of Executors\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/executors\n- **Request:**\n\n ```\ncurl http://localhost:8080/rest/clusters/dev/executors\n ```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n ```\n [\"order-executor\"]\n ```\n\n19.13.2. Retrieve Executor Information [GET] [/rest/clusters/{clustername}/executors/{executorName}]\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/executors/{executorName}\n- **Request:**\n\n ```\ncurl http://localhost:8080/rest/clusters/dev/executors/order-executor\n ```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\nThis resource returns a list of clients belonging to the provided cluster.\n\n19.14.1. Retrieve List of Client UUIDs\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/clientStats\n- **Request:**\n\n ```\n curl http://localhost:8080/rest/clusters/dev/clientStats\n ```\n\n- **Response:** 200 (application/json)\n- **Body:**\n\n ```\n [\n \"f3b1e0e9-ea67-41b2-aba5-ea7480f02a93\",\n \"cebf4dc9-852c-4605-a181-ffe1cca371a4\",\n \"2371ed5-26e0-4470-92c1-41ea17110ef6\",\n \"139990b3-fbc0-43a8-9c12-be53913333f7\",\n \"d0364a1e-8665-46a8-a1fd-be1af5580d07\",\n \"7f337f8a-3538-4b5c-8ffc-9d4ae459e956\",\n \"6ef9b6e5-5add-40d9-9319-ce502f55b5fc\",\n \"fead3a99-19de-431c-9dd0-d6ecc4a4b9c8\",\n \"e788e04e-2ded-4992-9d76-52c1973216e5\",\n \"654fc9fb-c5c1-48a0-9b69-0c129fce860f\"\n ]\n ```\n\n\n [/rest/clusters/{clustername}/clientStats/{clientUuid}]\n\n- **Request Type:** GET\n- **URL:** /rest/clusters/{clustername}/clientStats/{clientUuid}\n• **Request:**\n\n```\ncurl http://localhost:8080/rest/clusters/dev/clientStats/2371eed5-26e0-4470-92c1-41ea17110ef6\n```\n\n• **Response:** 200 (application/json)\n\n• **Body:**\n\n```json\n{\n \"type\": \"JAVA\",\n \"name\": \"hz.client_7\",\n \"address\": \"127.0.0.1\",\n \"clusterConnectionTimestamp\": 1507874427419,\n \"enterprise\": true,\n \"lastStatisticsCollectionTime\": 1507881309434,\n \"osStats\": {\n \"committedVirtualMemorySize\": 12976173056,\n \"freePhysicalMemorySize\": 3615662080,\n \"freeSwapSpaceSize\": 8447324160,\n \"maxFileDescriptorCount\": 1000000,\n \"openFileDescriptorCount\": 191,\n \"processCpuTime\": 252980000000,\n \"systemLoadAverage\": 83.0,\n \"totalPhysicalMemorySize\": 16756101120,\n \"totalSwapSpaceSize\": 8447324160\n },\n \"runtimeStats\": {\n \"availableProcessors\": 12,\n \"freeMemory\": 135665432,\n \"maxMemory\": 3724541952,\n \"totalMemory\": 361234432,\n \"uptime\": 6894992,\n \"usedMemory\": 225569000\n },\n \"nearCacheStats\": {\n \"CACHE\": {\n \"a-cache\": {\n \"creationTime\": 1507874429719,\n \"evictions\": 0,\n \"hits\": 0,\n \"misses\": 50,\n \"ownedEntryCount\": 0,\n \"expires\": 0,\n \"ownedEntryMemoryCost\": 0,\n \"lastPersistenceDuration\": 0,\n \"lastPersistenceKeyCount\": 0,\n \"lastPersistenceTime\": 0,\n \"lastPersistenceWrittenBytes\": 0,\n \"lastPersistenceFailure\": \"\"\n }\n }\n }\n}\n```\n19.14.3. Retrieve WAN Publisher Statistics [GET]\n[/rest/clusters/{clusternam}e/wanStats/{wanReplication}/publishers/{publis her}]\n\n- Request Type: GET\n- URL: /rest/clusters/{clusternam}e/wanStats/{wanReplication}/publishers/{publisher}\n- Request:\n\n```\ncurl http://localhost:8080/rest/clusters/dev/wanStats/devWanConfig/publishers/devPublish er\n```\n\n- Response: 200 (application/json)\n- Body:\n\n```\n{\n \"cluster\": \"dev\",\n \"configName\": \"devWanConfig\",\n \"publisherId\": \"devPublisher\",\n \"totalPublishedEventCount\": 1023,\n \"outboundQueueSize\": 10,\n \"maxOutboundQueueSize\": 5,\n \"time\": 1577696465000\n}\n```\n\n20. Clustered JMX\n\nHazelcast IMDG Enterprise\n\nClustered JMX via Management Center allows you to monitor clustered statistics of distributed objects from a JMX interface.\n\n20.1. Configuring Clustered JMX\n\nIn order to configure Clustered JMX, use the following command line parameters for your Management Center deployment.\n\n- `-Dhazelcast.mc.jmx.enabled=true` (default is false)\n- `-Dhazelcast.mc.jmx.port=9000` (optional, default is 9999)\n- `-Dcom.sun.management.jmxremote.ssl=false`\n- `-Dhazelcast.mc.jmx.rmi.port=9001` (optional, default is 9998)\n- `-Dhazelcast.mc.jmx.host=localhost` (optional, default is server's host name)\nWith embedded Jetty, you do not need to deploy your Management Center application to any container or application server.\n\nYou can start the Management Center application with Clustered JMX enabled as shown below.\n\n```\njava -Dhazelcast.mc.jmx.enabled=true\n -Dhazelcast.mc.jmx.port=9999\n -Dcom.sun.management.jmxremote.ssl=false -jar hazelcast-management-center-4.0.2.war\n```\n\nOnce the Management Center starts, you should see a log similar to the one below:\n\n```\nINFO: Management Center 3.3\nINFO: Starting Management Center JMX Service on port :9999\n```\n\nYou should be able to connect to the Clustered JMX interface using the address `localhost:9999`.\n\nYou can use `jconsole` or any other JMX client to monitor your Hazelcast IMDG cluster. As an example, below is the `jconsole` screenshot of the Clustered JMX hierarchy.\n\n**20.1.1. Enabling TLS/SSL for Clustered JMX**\n\nBy default, Clustered JMX is served unencrypted. To enable TLS/SSL for Clustered JMX, use the following command line parameters for your Management Center deployment:\n\n- `-Dhazelcast.mc.jmx.ssl=true` (default is false)\n- `-Dhazelcast.mc.jmx.ssl.keyStore=path to your keystore`\n- `-Dhazelcast.mc.jmx.ssl.keyStorePassword=password for your keystore`\nThe following is an example on how to start the Management Center with a TLS/SSL enabled Clustered JMX service on port 65432:\n\n```\njava -Dhazelcast.mc.jmx.enabled=true\n-Dhazelcast.mc.jmx.port=65432\n-Dhazelcast.mc.jmx.ssl=true\n-Dhazelcast.mc.jmx.ssl.keyStore=/some/dir/selfsigned.jks\n-Dhazelcast.mc.jmx.ssl.keyStorePassword=yourpassword -jar hazelcast-management-center-4.0.2.war\n```\n\nYou can encrypt the keystore password and pass it as a command line argument in encrypted form for improved security. See the Variable Replacers section for more information.\n\nThen, you can use the following command to connect to the Clustered JMX service using JConsole with the address localhost:65432:\n\n```\njconsole -J-Djavax.net.ssl.trustStore=/some/dir/selftrusted.ts -J-Djavax.net.ssl.trustStorePassword=trustpass\n```\n\n**Additional TLS/SSL Configuration Options**\n\nThe following are some additional command line arguments that you can use to configure TLS/SSL for clustered JMX:\n\n- `-Dhazelcast.mc.jmx.ssl.keyStoreType`: Type of the keystore. Its default value is JKS.\n- `-Dhazelcast.mc.jmx.ssl.keyManagerAlgorithm`: Name of the algorithm based on which the authentication keys are provided. The system default is used if none is provided. You can find out the default by calling the `javax.net.ssl.KeyManagerFactory#getDefaultAlgorithm` method.\n\n**20.2. Clustered JMX API**\n\nThe management beans are exposed with the following object name format:\n\n```\nManagementCenter[\"*cluster name*\\]:type=\"*object type*\",name=\"*object name*\",member=\"*cluster member IP address*\"\n```\n\nThe object name starts with the ManagementCenter prefix. Then it has the cluster name in brackets followed by a colon. After that, type, name and member attributes follow, each separated with a comma.\n\n- **type** is the type of object. Values are Clients, Executors, Maps, Members, MultiMaps, Queues, Counters, Services, and Topics.\n- **name** is the name of object.\n• **member** is the member address of object (only required if the statistics are local to the member).\n\nA sample bean is shown below.\n\n```\nManagementCenter[dev]:type=Services,name=OperationService,member=\"192.168.2.79:5701\"\n```\n\nHere is the list of attributes that are exposed from the Clustered JMX interface.\n\n- **ManagementCenter**\n - ManagementCenter\n - LicenseExpirationTime\n - Clusters\n - **ManagementCenter[<ClusterName>]**\n - `<ClusterName>`\n - MasterAddress\n - LicenseExpirationTime\n - **ClientStats**\n - `<Client UUID>`\n - HeapUsedMemory\n - HeapFreeMemory\n - HeapMaxMemory\n - HeapTotalMemory\n - ClientName\n - AvailableProcessors\n - Uptime\n - Enterprise\n - MemberConnection\n - ClusterConnectionTimestamp\n - LastStatisticsCollectionTime\n - UserExecutorQueueSize\n - CommittedVirtualMemorySize\n - FreePhysicalMemorySize\n - FreeSwapSpaceSize\n - MaxFileDescriptorCount\n - OpenFileDescriptorCount\n - ProcessCpuTime\n - SystemLoadAverage\n• TotalPhysicalMemorySize\n• TotalSwapSpaceSize\n• Version\n• Address\n• Type\n• CACHE\n • <Cache Name>\n • Evictions\n • Expirations\n • Hits\n • Misses\n • OwnedEntryCount\n • OwnedEntryMemoryCost\n • LastPersistenceDuration\n • LastPersistenceKeyCount\n • LastPersistenceTime\n • LastPersistenceWrittenBytes\n • LastPersistenceFailure\n • CreationTime\n• MAP\n • <Map Name>\n • Evictions\n • Expirations\n • Hits\n • Misses\n • OwnedEntryCount\n • OwnedEntryMemoryCost\n • LastPersistenceDuration\n • LastPersistenceKeyCount\n • LastPersistenceTime\n • LastPersistenceWrittenBytes\n • LastPersistenceFailure\n • CreationTime\n• Clients\n • <Client Address>\n- Address\n- CanonicalHostName\n- ClientName\n- ClientType\n- IpAddress\n- Labels\n- Uuid\n\n- Executors\n - <Executor Name>\n - Cluster\n - Name\n - StartedTaskCount\n - CompletedTaskCount\n - CancelledTaskCount\n - PendingTaskCount\n\n- Maps\n - <Map Name>\n - Cluster\n - Name\n - BackupEntryCount\n - BackupEntryMemoryCost\n - CreationTime\n - DirtyEntryCount\n - Events\n - GetOperationCount\n - HeapCost\n - Hits\n - LastAccessTime\n - LastUpdateTime\n - LockedEntryCount\n - MaxGetLatency\n - MaxPutLatency\n - MaxRemoveLatency\n - OtherOperationCount\n - OwnedEntryCount\n• PutOperationCount\n• RemoveOperationCount\n• AverageGetLatency\n• AveragePutLatency\n• AverageRemoveLatency\n\n• ReplicatedMaps\n • <Replicated Map Name>\n • Cluster\n • Name\n • BackupEntryCount\n • BackupEntryMemoryCost\n • CreationTime\n • DirtyEntryCount\n • Events\n • GetOperationCount\n • HeapCost\n • Hits\n • LastAccessTime\n • LastUpdateTime\n • LockedEntryCount\n • MaxGetLatency\n • MaxPutLatency\n • MaxRemoveLatency\n • OtherOperationCount\n • OwnedEntryCount\n • PutOperationCount\n • RemoveOperationCount\n • AverageGetLatency\n • AveragePutLatency\n • AverageRemoveLatency\n\n• Members\n • <Member Address>\n • Uuid\n • CpMemberUuid\n • ConnectedClientCount\n- HeapFreeMemory\n- HeapMaxMemory\n- HeapTotalMemory\n- HeapUsedMemory\n- IsMaster\n- OwnedPartitionCount\n\n- MultiMaps\n - <MultiMap Name>\n - Cluster\n - Name\n - BackupEntryCount\n - BackupEntryMemoryCost\n - CreationTime\n - DirtyEntryCount\n - Events\n - GetOperationCount\n - HeapCost\n - Hits\n - LastAccessTime\n - LastUpdateTime\n - LockedEntryCount\n - MaxGetLatency\n - MaxPutLatency\n - MaxRemoveLatency\n - OtherOperationCount\n - OwnedEntryCount\n - PutOperationCount\n - RemoveOperationCount\n - AverageGetLatency\n - AveragePutLatency\n - AverageRemoveLatency\n\n- Queues\n - <Queue Name>\n - Cluster\n - Name\n- MinAge\n- MaxAge\n- AverageAge\n- OwnedItemCount\n- BackupItemCount\n- OfferOperationCount\n- OtherOperationsCount\n- PollOperationCount\n- RejectedOfferOperationCount\n- EmptyPollOperationCount\n- EventOperationCount\n- CreationTime\n\n- Counters\n - `<Counter Name>`\n - Cluster\n - Name\n - ReplicaCount\n - Time\n - OpsPerSecInc (for each member)\n - OpsPerSecDec (for each member)\n - Value (for each member)\n\n- Services\n - ConnectionManager\n - ActiveConnectionCount\n - ClientConnectionCount\n - ConnectionCount\n - EventService\n - EventQueueCapacity\n - EventQueueSize\n - EventThreadCount\n - OperationService\n - executedOperationCount\n - OperationExecutorQueueSize\n - OperationThreadCount\n - RemoteOperationCount\n- ResponseQueueSize\n- RunningOperationsCount\n\n- PartitionService\n - ActivePartitionCount\n - PartitionCount\n\n- ProxyService\n - ProxyCount\n\n- ManagedExecutor[hz::async]\n - Name\n - CompletedTaskCount\n - MaximumPoolSize\n - PoolSize\n - QueueSize\n - RemainingQueueCapacity\n - Terminated\n\n- ManagedExecutor[hz::client]\n - Name\n - CompletedTaskCount\n - MaximumPoolSize\n - PoolSize\n - QueueSize\n - RemainingQueueCapacity\n - Terminated\n\n- ManagedExecutor[hz::global-operation]\n - Name\n - CompletedTaskCount\n - MaximumPoolSize\n - PoolSize\n - QueueSize\n - RemainingQueueCapacity\n - Terminated\n\n- ManagedExecutor[hz::io]\n - Name\n - CompletedTaskCount\n - MaximumPoolSize\n- `PoolSize`\n- `QueueSize`\n- `RemainingQueueCapacity`\n- `Terminated`\n\n- `ManagedExecutor[hz::query]`\n - `Name`\n - `CompletedTaskCount`\n - `MaximumPoolSize`\n - `PoolSize`\n - `QueueSize`\n - `RemainingQueueCapacity`\n - `Terminated`\n\n- `ManagedExecutor[hz::scheduled]`\n - `Name`\n - `CompletedTaskCount`\n - `MaximumPoolSize`\n - `PoolSize`\n - `QueueSize`\n - `RemainingQueueCapacity`\n - `Terminated`\n\n- `ManagedExecutor[hz::system]`\n - `Name`\n - `CompletedTaskCount`\n - `MaximumPoolSize`\n - `PoolSize`\n - `QueueSize`\n - `RemainingQueueCapacity`\n - `Terminated`\n\n- `Topics`\n - `<Topic Name>`\n - `Cluster`\n - `Name`\n - `CreationTime`\n - `PublishOperationCount`\n - `ReceiveOperationCount`\n20.3. Integrating with New Relic\n\nUse the Clustered JMX interface to integrate the Hazelcast Management Center with New Relic. To perform this integration, attach the New Relic Java agent and provide an extension file that describes which metrics will be sent to New Relic.\n\nSee Custom JMX instrumentation by YAML on the New Relic webpage.\n\nThe following is an example Map monitoring .yml file for New Relic:\n\n```yaml\nname: Clustered JMX\nversion: 1.0\nenabled: true\n\njmx:\n - object_name: ManagementCenter[clusternam]:type=Maps,name=ormapname\n metrics:\n - attributes: PutOperationCount, GetOperationCount, RemoveOperationCount, Hits, BackupEntryCount, OwnedEntryCount, LastAccessTime, LastUpdateTime\n type: simple\n - object_name: ManagementCenter[clusternam]:type=Members,name=\"member address in double quotes\"\n metrics:\n - attributes: OwnedPartitionCount\n type: simple\n```\n\nPut the .yml file in the extensions directory in your New Relic installation. If an extensions directory\nAfter you set your extension, attach the New Relic Java agent and start the Management Center as shown below.\n\n```bash\njava -javaagent:/path/to/newrelic.jar -Dhazelcast.mc.jmx.enabled=true\n -Dhazelcast.mc.jmx.port=9999 -jar hazelcast-management-center-4.0.2.war\n```\n\nIf your logging level is set to `FINER`, you should see the log listing in the file `newrelic_agent.log`, which is located in the `logs` directory in your New Relic installation. The following is an example log listing:\n\n```none\n name=\"192.168.2.79:5701\", matches 1\n matches 1\n```\n\nThen you can navigate to your New Relic account and create Custom Dashboards. See [Creating custom dashboards](#).\n\nWhile you are creating the dashboard, you should see the metrics that you are sending to New Relic from the Management Center in the **Metrics** section under the JMX directory.\n\n### 20.4. Integrating with AppDynamics\n\nUse the Clustered JMX interface to integrate the Hazelcast Management Center with [AppDynamics](#).\nTo perform this integration, attach the AppDynamics Java agent to the Management Center. For agent installation, see the Install the App Agent for Java page. For monitoring on AppDynamics, see the Using AppDynamics for JMX Monitoring page.\n\nAfter installing AppDynamics agent, you can start the Management Center as shown below:\n\n```java\njava -javaagent:/path/to/javaagent.jar \n -Dhazelcast.mc.jmx.enabled=true \n -Dhazelcast.mc.jmx.port=9999 -jar hazelcast-management-center-4.0.2.war\n```\n\nWhen the Management Center starts, you should see the logs below:\n\n```\nStarted AppDynamics Java Agent Successfully.\nHazelcast Management Center starting on port 8080 at path : /\n```\n\n21. Management Center Configuration Tool\n\nThe Management Center Configuration Tool (MC-Conf) is a command line tool that allows you to update certain parts of the Management Center configuration by using its built-in tasks. You can use the `mc-conf.sh` or `mc-conf.bat` script to run the MC-Conf tool.\n\n![You must run the MC-Conf tool on the same machine where the Management Center web application is deployed.]\n\n21.1. Built-In Help\n\nIn order to see all available commands, run the MC-Conf script with no arguments as shown below.\n\n```\n./mc-conf.sh\n```\n\nAs the result, you should see an output similar to below.\nHazelcast Management Center Configuration Tool 4.0\n\nUsage: mc-conf [-hV] COMMAND TASK\n\nCommand line tool for interacting with Hazelcast Management Center configuration.\n\nGlobal options are:\n- -h, --help Show this help message and exit.\n- -V, --version Print version information and exit.\n\nCommands:\ncluster Manage Cluster Connection Configs\nuser Manage Default Security Provider Users\nldap Manage LDAP Security Provider\nactive-directory Manage Active Directory Security Provider\njaas Manage JAAS Security Provider\nsecurity General Security Provider management\n\nWhen you choose a specific subcommand from the list above, you can see all tasks available for it. See the following example:\n\n$ ./mc-conf.sh user\nUsage: mc-conf user [-hV] TASK\nManage Default Security Provider Users\n- -h, --help Show this help message and exit.\n- -V, --version Print version information and exit.\n\nCommands:\ncreate Create a new user record in the default security provider.\n *Important notice* Make sure that Management Center web application is stopped (offline) before starting this task.\n\nupdate-password Change password for the given user record in the default security provider.\n *Important notice* Make sure that Management Center web application is stopped (offline) before starting this task.\n\nYou can also get help for any task by using the -h (or --help) command line option. See the following example:\n$ ./mc-conf.sh user create -h\nUsage: mc-conf user create [-hvV] [-p=<password>] [-H=<homedir>]\n-n=<username> -r=<role>\n\nCreate a new user record in the default security provider.\n*Important notice* Make sure that Management Center web application is stopped (offline) before starting this task.\n\n-H, --home=<homedir> Optional path to Management Center home directory. By default ~/hazelcast-mc/ is used.\n-n, --username=<username> Username for the user record.\n-p, --password=<password> Password for the user record. Provide value directly or use without value to enter securely with interactive prompt.\n-r, --role=<role> Roles for the user record. Valid values: readonly, readwrite, metricsonly, admin.\n-h, --help Show this help message and exit.\n-V, --version Print version information and exit.\n-v, --verbose Enable full logging output. Use this option to see full stack traces.\n\n21.2. Configuring Cluster Connection\n\nThe cluster add task adds a new connection configuration for a cluster. Note that you must stop the Management Center web application before running this task.\n\nYou can use this task for various scripting purposes, and automatically configuring Management Center, without the need for a manual cluster connection configuration through UI.\n\nIf you have used a non-default Management Center home directory location, you must provide the path to the home directory with the -H (or --home) option.\n\n21.3. Creating Users\n\nThe user create task creates a new user in the default security provider. Note that you must stop the Management Center web application before running this task.\n\nYou can use this task for various scripting purposes. See the Hazelcast Docker Code Samples repository for an example of Docker image for the Management Center container with a built-in user account.\n\nIf you have used a non-default Management Center home directory location, you must provide the path to the home directory with the -H (or --home) option.\n21.4. Changing User Password\n\nThe `user update-password` task resets the password of a specified user in the default security provider. Note that you must stop the Management Center web application before running this task.\n\nYou can use this task as a recovery mechanism for the Management Center’s administrator user account.\n\nIf you have used a non-default Management Center home directory location, you must provide the path to the home directory with the `-H` (or `--home`) option.\n\n21.5. Configuring LDAP Security Provider\n\nThe `ldap configure` task configures the LDAP security provider. Note that you must stop the Management Center web application, before running this task.\n\nYou can use this task for various scripting purposes and automatically configuring Management Center without the need for a manual security provider configuration through UI.\n\nYou can encrypt the LDAP password before saving with this task. See the Variable Replacers section for more information.\n\nAs with the UI based LDAP configuration, you can also use keystore for secure password storage, by using the optional `--key-store-*` options, as shown in the examples below.\n\nIf you want to use the built-in Management Center managed keystore, you can add the following options: `--ks-create --key-store=<hazelcast-mc directory>/mc.jceks --key-store-password=<password>`. This creates a keystore in the default Management Center directory, and saves the LDAP password in it. If you want to customize the keystore name or Management Center directory when starting Management Center, you need to reflect that with the `--key-store=<path>` option.\n\nIf you want to use the existing externally managed keystore, you can use the following options: `--key-store=<keystore path> --key-store-password=<password> [--key-store-type=<type> --key-store-provider=<provider>]`. Note that if the keystore with such path doesn’t exist, task fails.\n\nYou still need to properly configure Management Center to use keystore. See LDAP Authentication section for details on using the built-in and existing keystores.\n\nIf you have used a non-default Management Center home directory location, you must provide the path to the home directory with the `-H` (or `--home`) option.\n\n21.6. Updating LDAP Password\n\nThe `ldap update-password` task updates the encrypted LDAP password stored in the keystore. It expects information about the keystore such as its location and password and the new LDAP password that you want to use. See the LDAP Authentication section for more information on the\nencrypted LDAP passwords. After updating the LDAP password, you need to click on the **Reload Security Config** button on the login page.\n\n## 21.7. Configuring Active Directory Security Provider\n\nThe `active-directory configure` task configures the Active Directory security provider. Note that you must stop the Management Center web application before running this task.\n\nYou can use this task for various scripting purposes, and automatically configuring Management Center, without the need for a manual security provider configuration through UI.\n\nIf you have used a non-default Management Center home directory location, you must provide the path to the home directory with the `-H` (or `--home`) option.\n\n## 21.8. Configuring JAAS Security Provider\n\nThe `jaas configure` task configures the JAAS security provider. Note that you must stop the Management Center web application before running this task.\n\nYou can use this task for various scripting purposes, and automatically configuring Management Center, without the need for a manual security provider configuration through UI.\n\nIf you have used a non-default Management Center home directory location, you must provide the path to the home directory with the `-H` (or `--home`) option.\n\n## 21.9. Resetting Security Provider\n\nThe `security reset` task resets current security provider used in the Management Center. For the default security provider it also deletes all built-in user accounts. Note that you must stop the Management Center web application before running this task.\n\nYou can use this task as a recovery mechanism for the Management Center deployment in case if a non-default security provider is configured. In case of the default security provider, you can also use the `user create` or `user update-password` task as the recovery mechanism.\n\nIf you have used a non-default Management Center home directory location, you must provide the path to the home directory with the `-H` (or `--home`) option.\n\n## 21.10. Advanced Features\n\nMC-Conf supports interactive options for secure processing of passwords. To use it, you need to use the password option without providing a value, i.e., instead of `--password=<password>` use `--password`. When you use this option without providing a value, you will get a prompt to enter a value on the console. An example of the interactive option usage is shown below.\nAs you see in the above example, the password input is not echoed to the console since it is provided with the secure interactive mode.\n\nAnother advanced feature of MC-Conf is the support for argument files. When an argument beginning with the character `@` is encountered, it is treated as a path leading to a text file. The contents of that file are automatically expanded into the current task. An example of the argument file usage is shown below.\n\n```\n$ ./mc-conf.sh user update-password @arg-file.txt\nSuccessfully changed password for user 'admin'.\n$ cat arg-file.txt\n--username=admin --password=mnb3c4s0\n```\n\n22. Phone Home\n\nHazelcast uses phone home data to learn about usage of Hazelcast Management Center.\n\nHazelcast Management Center instances initially call our phone home server 30 minutes after they are started and once every 24 hours thereafter.\n\nWhat is sent in?\n\nThe following information is sent in a phone home:\n\n- Hazelcast Management Center version\n- Authentication provider used (Default, LDAP, ActiveDirectory, JAAS)\n- Whether clustered REST is enabled or not\n- Whether clustered JMX is enabled or not\n- Whether TLS is enabled or not\n - If TLS is enabled, whether mutual authentication is enabled or not\n- Whether Management Center is deployed on an application server or used in standalone mode\n - If not in standalone mode, type of the application server\n- Number of users (if the default security provider is used)\n- Number of clusters\n- Management Center uptime\n- Minimum and maximum cluster sizes\n- Minimum and maximum cluster versions\n• Total number of members\n• Size of the Hazelcast Management Center home directory\n• Hash value of Hazelcast Management Center license key\n• Environment Information:\n ◦ Name of operating system\n ◦ Version of installed Java\n\nFor each user login, we store the following information and send it in a phone home:\n\n• Browser (Chrome, Firefox, IE etc.)\n• Browser major version\n• Operating system\n• Operating system version\n• Screen height and width\n• Window height and width\n\nDisabling Phone Homes\n\nSet the `hazelcast.mc.phone.home.enabled` system property to false on the Java command line.\n\nPhone Home URL\n\nhttp://phonehome.hazelcast.com/pingMc\n\n23. Management Center Documentation\n\nTo see the Management Center documentation (this Reference Manual), click on the Documentation button located at the toolbar. This Management Center manual appears as a tab.\n\n24. Suggested Heap Size\n\nTable 1. For 2 Cluster Members\n\n<table>\n<thead>\n<tr>\n<th>Management Center Heap Size</th>\n<th># of Maps</th>\n<th># of Queues</th>\n<th># of Topics</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>256m</td>\n<td>3k</td>\n<td>1k</td>\n<td>1k</td>\n</tr>\n<tr>\n<td>1024m</td>\n<td>10k</td>\n<td>1k</td>\n<td>1k</td>\n</tr>\n</tbody>\n</table>\n\nTable 2. For 10 Members\n\n<table>\n<thead>\n<tr>\n<th>Management Center Heap Size</th>\n<th># of Maps</th>\n<th># of Queues</th>\n<th># of Topics</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>256m</td>\n<td>50</td>\n<td>30</td>\n<td>30</td>\n</tr>\n<tr>\n<td>1024m</td>\n<td>2k</td>\n<td>1k</td>\n<td>1k</td>\n</tr>\n</tbody>\n</table>\n### Table 3. For 20 Members\n\n<table>\n<thead>\n<tr>\n<th>Management Center Heap Size</th>\n<th># of Maps</th>\n<th># of Queues</th>\n<th># of Topics</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>256m [1: With 256m heap, Management Center is unable to collect statistics.]</td>\n<td>N/A</td>\n<td>N/A</td>\n<td>N/A</td>\n</tr>\n<tr>\n<td>1024m</td>\n<td>1k</td>\n<td>1k</td>\n<td>1k</td>\n</tr>\n</tbody>\n</table>\n\n#### 25. Configuring the maximum cache size\n\nYou can configure the maximum size of the cache containing timestamped cluster states using the `hazelcast.mc.cache.max.size` system property. This value is 768 by default. Decreasing this limit can significantly lower the heap usage of Management Center in cases when the cluster contains a lot of maps.\n\n#### 25.1. Approximate heap usages\n\nThe tables below list reference data about the heap usage of Management Center, depending on the cluster member count, map count in each member, and `hazelcast.mc.cache.max.size` setting.\n\n**Table 4. Heap usages with 2 cluster members**\n\n<table>\n<thead>\n<tr>\n<th><code>hazelcast.mc.cache.max.size</code></th>\n<th>2000 maps</th>\n<th>4000 maps</th>\n<th>6000 maps</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>256</td>\n<td>440 Mb</td>\n<td>810 Mb</td>\n<td>1170 Mb</td>\n</tr>\n<tr>\n<td>512</td>\n<td>800 Mb</td>\n<td>1530 Mb</td>\n<td>2260 Mb</td>\n</tr>\n<tr>\n<td>768</td>\n<td>1150 Mb</td>\n<td>2240 Mb</td>\n<td>3320 Mb</td>\n</tr>\n</tbody>\n</table>\n\n**Table 5. Heap usages with 10 cluster members**\n\n<table>\n<thead>\n<tr>\n<th><code>hazelcast.mc.cache.max.size</code></th>\n<th>2000 maps</th>\n<th>4000 maps</th>\n<th>6000 maps</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>256</td>\n<td>1750 Mb</td>\n<td>3560 Mb</td>\n<td>5290 Mb</td>\n</tr>\n<tr>\n<td>512</td>\n<td>3530 Mb</td>\n<td>6960 Mb</td>\n<td>10030 Mb</td>\n</tr>\n<tr>\n<td>768</td>\n<td>4340 Mb</td>\n<td>9770 Mb</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n#### 26. Troubleshooting\n\n#### 26.1. Horizontal Scrollbar in Tables when Using macOS\n\nMacOS automatically shows a horizontal scrollbar in the status tables of Management Center, when you scroll through a table content. See below for an example view:\nThe scrollbar should hide shortly after you stop scrolling. This is the default behavior and it shouldn’t cause any inconvenience. However, if you still want to change it, address \"Show scroll bars\" section of the “Change General preferences on Mac” guide.\n\nAppendix A: Migration Guides\n\nThis appendix provides information on compatibility related changes for Hazelcast Management Center releases.\n\nA.1. Hazelcast Management Center 3.12.x\n\n- Default home directory location has been changed from `<user-home>/hazelcast-mancenter<version>` to `<user-home>/hazelcast-mc`.\n- Parameter to change home directory location has been changed from `hazelcast.mancenter.home` to `hazelcast.mc.home`.\n- The `UpdateLdapPassword` utility (available via `updateLdapPassword.sh` or `updateLdapPassword.bat` scripts) has been merged into the MC Conf tool (available via the `mc-conf.sh` or `mc-conf.bat` scripts).\n\nA.2. Hazelcast Management Center 3.10.x\n\n- Hazelcast Management Center's default URL has been changed from `localhost:8080/mancenter` to `localhost:8080/hazelcast-mancenter`.\n- Default home directory location has been changed from `<user-home>/mancenter<version>` to\nA.3. Hazelcast Management Center 3.8.x\n\nStarting with Management Center 3.8.4, you can use the following system properties for Clustered JMX via Management Center:\n\n- `-Dhazelcast.mc.jmx.rmi.port=9001`\n- `-Dhazelcast.mc.jmx.host=localhost`\n\nSee the Clustered JMX via Management Center chapter.\n\nAppendix B: User Interface Logs\n\nUsing the \"UI Logs\" page of the \"Settings\" menu, you can see the log entries related to the Management Center user interface. This page looks like the following:\nThis is basically useful to make the troubleshooting easier related to the issues in the user interface. You can see the timestamp and type of each log entry.\n\nYou can reorder the entries by their timestamps any types, and also filter them by giving a keyword to the **Data** field such as \"auth\", \"map\" and \"session\".\n\nYou can pause the log flow using the **Pause** button, copy the log entries to the clipboard using the **Copy** button (so that the entries can be examined in detail) and resume the flow using the **Resume** button on the page.\n\nYou may only need to share the information in these logs if requested by the Hazelcast's support team."}}},{"rowIdx":64,"cells":{"id":{"kind":"string","value":"0a80efe5789801f01047c5c6107cd7ef5bbed564"},"text":{"kind":"string","value":"SYSTEM AND METHOD FOR A CLOUD COMPUTING ABSTRACTION WITH SELF-SERVICE PORTAL FOR PUBLISHING RESOURCES\n\nApplicant: CSC Agility Platform, Inc., Falls Church, VA (US)\n\nInventors: Frank Martinez, La Canada, CA (US); Eric Pulier, Los Angeles, CA (US)\n\nAssignee: CSC Agility Platform, Inc., Falls Church, VA (US)\n\nNotice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 170 days.\n\nAppl. No.: 13/842,413\nFiled: Mar. 15, 2013\n\nPrior Publication Data\nUS 2014/0278623 A1 Sep. 18, 2014\n\nRelated U.S. Application Data\nContinuation-in-part of application No. 13/354,275, filed on Jan. 19, 2012, now Pat. No. 9,069,509, which is a continuation-in-part of application No. 13/009,774, filed on Jan. 19, 2011, now Pat. No. 8,931,038, which is a continuation-in-part of application No. 12/488,424, filed on Jun. 19, 2009, now Pat. No. 8,514,868.\n\n\nInt. Cl.\nG06F 9/44 (2006.01)\nG06Q 10/00 (2012.01)\nG06Q 10/06 (2012.01)\n\nU.S. Cl.\nCPC G06Q 10/06 (2013.01); G06F 8/36 (2013.01)\n\nField of Classification Search\nCPC G06Q 10/06; G06F 8/36\nSee application file for complete search history.\n\nReferences Cited\nU.S. PATENT DOCUMENTS\n6,345,361 B1 2/2002 Jerger et al.\n6,473,800 B1 10/2002 Jerger et al.\n\nFOREIGN PATENT DOCUMENTS\n\nOTHER PUBLICATIONS\n\nPrimary Examiner — Sujay Koneru\nAttorney, Agent, or Firm — Sheppard Mullin Richter & Hampton LLP\n\nABSTRACT\nIn embodiments of the present invention, improved capabilities are described for a virtualization environment adapted for development and deployment of at least one software workload, the virtualization environment having a metamodel framework that allows the association of a policy to the software workload upon development of the workload that is applied upon deployment of the software workload.\n\n20 Claims, 21 Drawing Sheets\n### References Cited\n\n#### U.S. PATENT DOCUMENTS\n\n<table>\n<thead>\n<tr>\n<th>Patent Number</th>\n<th>Date</th>\n<th>Inventor/Assignee</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2011/0261828 A1</td>\n<td>10/2011</td>\n<td>Smith</td>\n</tr>\n<tr>\n<td>2012/005236 A1</td>\n<td>1/2012</td>\n<td>Deng et al.</td>\n</tr>\n<tr>\n<td>2012/005724 A1</td>\n<td>1/2012</td>\n<td>Lee</td>\n</tr>\n<tr>\n<td>2012/0173709 A1</td>\n<td>7/2012</td>\n<td>Li et al.</td>\n</tr>\n<tr>\n<td>2012/0179824 A1</td>\n<td>7/2012</td>\n<td>Jackson</td>\n</tr>\n<tr>\n<td>2012/0185821 A1</td>\n<td>7/2012</td>\n<td>Yaseen et al.</td>\n</tr>\n<tr>\n<td>2012/0192146 A1</td>\n<td>7/2012</td>\n<td>Arnold et al.</td>\n</tr>\n<tr>\n<td>2012/0229499 A1</td>\n<td>9/2012</td>\n<td>Tsao et al.</td>\n</tr>\n<tr>\n<td>2012/0324609 A1</td>\n<td>12/2012</td>\n<td>Noor et al.</td>\n</tr>\n<tr>\n<td>2013/0069940 A1*</td>\n<td>3/2013</td>\n<td>Shao</td>\n</tr>\n<tr>\n<td>2013/0263209 A1</td>\n<td>10/2013</td>\n<td>Panuganty</td>\n</tr>\n</tbody>\n</table>\n\n#### FOREIGN PATENT DOCUMENTS\n\n<table>\n<thead>\n<tr>\n<th>Patent Number</th>\n<th>Date</th>\n<th>Inventor/Assignee</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>WO 2009155574</td>\n<td>12/2009</td>\n<td></td>\n</tr>\n<tr>\n<td>WO 2011091056</td>\n<td>7/2011</td>\n<td></td>\n</tr>\n<tr>\n<td>WO 2012060064</td>\n<td>5/2012</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n* cited by examiner\n\n### OTHER PUBLICATIONS\n\nFIG. 8\n\n700 PROVIDING A VIRTUAL PRIVATE CLOUD (VPC)\n703 RECEIVING A REQUEST TO PERFORM A COMPUTER WORKLOAD\n706 IDENTIFYING A CLOUD COMPUTING RESOURCE TO PERFORM THE COMPUTER WORKLOAD\n709 PROVIDING THE CLOUD COMPUTING RESOURCE\n712 DEPLOYING THE CLOUD COMPUTING RESOURCE\n715 USING THE CLOUD COMPUTING RESOURCE TO PERFORM THE COMPUTER WORKLOAD\n718 APPLYING A POLICY/CONSTRAINT ON THE CLOUD COMPUTING RESOURCE\n721\nFIG. 9A\n## MANAGER\n\n### Class/Board\n- Dev Environment\n - VM Linux (CentOS 5.6)\n - VM Linux (CentOS 5.6)\n - Integration/Test Environment\n - QA Environment\n - Pre-Production Environment\n - Sandbox Environment\n- QA Environment\n- QA Pre-Production Environment\n- QA Sandbox Environment\n- QA QA Environment\n- QA Pre-Production Environment\n- QA Sandbox Environment\n\n### Environment\n- SM Linux (CentOS 5.6) Desktop\n- SM Linux (CentOS 5.6) Desktop\n- Virtual Machine Instance Properties\n\n### Virtual Machine Instance Properties\n- SM Linux (CentOS 5.6) Desktop\n - Brand: SM Linux (CentOS 5.6) Desktop\n - Status: BM (Small/Medium Business) Desktop\n - Bootable: Yes\n - 4GB RAM/512MB HDD\n\n### Commands\n- Start Virtual Machine\n- Attach Msvm\n- Mount Volume\n- Boot Script\n- Remove\n\n### Resources\n- Process: 1.8 GHz Core\n- Memory: 2.0 GB\n- Disk: 10.0 GB\n- Public IP: 192.168.10.10\n- Private IP: 192.168.10.10\n\n### Snapshots\n\n### Track List\n\n<table>\n<thead>\n<tr>\n<th>Operation</th>\n<th>Status</th>\n<th>Started</th>\n<th>Completed</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Build Stack</td>\n<td>Complete</td>\n<td>Feb 28, 2010 11:23 PM</td>\n<td>Feb 28, 2010 11:46 PM</td>\n</tr>\n<tr>\n<td>Build Stack</td>\n<td>Complete</td>\n<td>Feb 28, 2010 11:23 PM</td>\n<td>Feb 28, 2010 11:46 PM</td>\n</tr>\n<tr>\n<td>Build Stack</td>\n<td>Complete</td>\n<td>Feb 28, 2010 11:23 PM</td>\n<td>Feb 28, 2010 11:46 PM</td>\n</tr>\n</tbody>\n</table>\n\n**FIG. 9D**\nFIGURE 15\nSYSTEM AND METHOD FOR A CLOUD COMPUTING ABSTRACTION WITH SELF-SERVICE PORTAL FOR PUBLISHING RESOURCES\n\nCROSS-REFERENCE TO RELATED APPLICATIONS\n\n\nBACKGROUND\n\nField of the Disclosure\n\nThe present invention relates to the field of cloud computing, and more particularly, the invention relates to systems and methods for securing, controlling and managing cloud services, applications, platforms and infrastructure.\n\nCompanies have begun offering businesses a new cloud computing outsourcing option that promises reduced costs, improved availability, improved scalability, and reduced time to deploy new applications. These companies act as managed service providers that rent virtual computer, storage, and Internet connectivity services for variable periods on a pay-per-use basis from large pools of re-purposable, multi-tenant computing resources. Such cloud infrastructure providers include Amazon Web Services®, Amazon EC2®, GoGrid®, Joyent®, and Mosso®.\n\nMany businesses, however, are currently unable to use cloud infrastructure because of a lack of security, control, and manageability of the computing capacity rented from the cloud infrastructure providers. These problems prevent such businesses from maximizing their use of cloud infrastructure, which includes virtual server instances, storage, and Internet bandwidth. Enterprises also have difficulty identifying what cloud resources they should use, and how they should use them, such that usage is consistent with the technical, operational, and business needs of the enterprise.\n\nSUMMARY\n\nAccording to various embodiments of the invention, systems and methods are provided for one or more cloud computing abstraction layers. Through various embodiments of the present invention, a user can plan cloud-computing services, build a cloud-computing service, publish the cloud-computing service for consumption by users, or run the cloud-computing service. Some embodiments of the present invention provide access to disparate public or private cloud-computing resources through a common interface. Additionally, some embodiments can apply governance uniformly over disparate public or private cloud-computing resources.\n\nSome systems may, for example, enable self-service access to cloud-computing resources by end-users, developers, and admins; automated services with respect to cloud-computing services comprising of one or more cloud-computing resources (e.g., management, building, configuration, publication, validation, and development and deployment of cloud-computing services); rapid provisioning (e.g., deployment, release, scheduling, control etc.) of cloud-computing resources within a cloud-computing service; governance control of cloud-computing resources within a cloud-computing service (e.g., application of security and non-security policies to cloud-computing resources), audit control of cloud-computing services; or secure access to cloud-computing services. Accordingly, embodiments of the present invention provide on-demand access by internal users, external users (e.g., customers, service partners), and developers to cloud-computing services, such as infrastructure-as-a-service (IaaS), platform-as-a-service (PaaS), and software-as-a-service (SaaS), provided from a governed federation of internal (private cloud) and external cloud (commercial cloud) service providers. Some such embodiments allow for rapid and dynamic deployment and scaling of cloud-computing services. A private cloud may comprise, for example, Eucalyptus Systems, VMware® vSphere®, or Microsoft® HyperV®; and a public cloud may comprise, for example, Amazon EC2®, Amazon Web Services®, Terremark®, Savvis®, or GoGrid®.\n\nAccording to one embodiment of the invention, the system provides a cloud-computing service from a cloud-computing environment comprising a plurality of cloud-computing resources, the system comprising: a management module configured to manage a cloud-computing resource of the plurality of cloud-computing resources as a cloud-computing service, wherein the cloud-computing service performs a computer workload and the cloud-computing service comprises the cloud-computing resource; an adapter configured to connect to the cloud-computing resource to the system and translate a management instruction received from the management module (e.g., intermediate representation of a command from a client) into a cloud application program interface call for the cloud-computing resource (e.g. proprietary API call for Amazon EC2®); a cloud service bus configured to route the management instruction from the management module to the adapter; a consumption module configured to allow a user to subscribe the cloud-computing service; a planning module configured to plan the cloud-computing service; and a build module configured to build the cloud-computing service from the cloud-computing resource and publish the cloud-computing service to the consumption module. In some such embodiments, the system provides a user interface configured to provide access to the system as a virtual private cloud. The system may further comprise a cloud model utilized by the adapter to translate the management instruction to the (target) cloud API call.\n\nIn certain embodiments, the virtual private cloud is utilized for operation of a cloud-computing service in accordance with the present invention. In particular embodiments,\na computer workload (e.g., application, server software, software development environment, software test environment) is a unit of computing processing that is performed via an IaaS, PaaS, or SaaS. For example, IaaS may comprise instances of Microsoft® Windows or Linux running on a virtual computer, or a Desktop-as-a-service (DaaS) provided by Citrix® or VMware®; a PaaS may comprise a database server (e.g., MySQL® server), Samba server, Apache® server, Microsoft® IIS.NET server, Java® runtime, or Microsoft® .NET® runtime, Linux-Apache-MySQL-PHP (LAMP) server, Microsoft® Azure, or Google® AppsEngine; a SaaS may comprise Salesforce®, Google® Apps, or other software application that can be deployed as a cloud service, such as in a web services model. A cloud-computing resource may be a physical or virtual computing resource (e.g., virtual machine). In some embodiments, the cloud-computing resource may be a storage resource (e.g., Storage Area Network (SAN), Network File System (NFS), or Amazon S3®), a network resource (e.g., firewall, load-balancer, or proxy server), an internal private resource, an external private resource, a secure public resource, an infrastructure-as-a-service (IaaS) resource, a platform-as-a-service (PaaS) resource, or a software-as-a-service (SaaS) resource. Hence, in some embodiments, a cloud-computing service provided may comprise an IaaS, PaaS, or SaaS provided by private or commercial (e.g., public) cloud service provider, such as Amazon Web Services®, Amazon EC2®, GoGrid®, Joyent®, Mosso®, or the like.\n\nIn various embodiments, the management module that manages the cloud-computing service comprises provisioning the cloud-computing service for a virtual private cloud, releasing the cloud-computing service for the virtual private cloud, accounting for usage of the cloud-computing service in the virtual private cloud, or monitoring the cloud-computing service. For example, in some embodiments, the management module manages cloud-computing resources for a cloud-computing service being offered by the system by provisioning a cloud-computing resource for the cloud-computing service, deploying a cloud-computing resource for the cloud-computing service, or releasing a cloud-computing resource being used by the cloud-computing service. In some embodiments, the provisioning involves starting, stopping, or generally controlling an instance of a cloud-computing resource (e.g., IaaS providing an instance of Linux) on behalf of a cloud-computing service. For example, an embodiment may launch scripts to start an instance of a cloud-computing resource, launch scripts to securely (e.g., via encryption) attach a file system (e.g., a storage volume) to the instantiation of the cloud-computing resource, or so that the cloud-computing resource can access local or remote client data securely, and then connect a client to the instantiation through a virtual private network (VPN) connection between the client’s local network and the cloud providers network.\n\nIn further embodiments, the management module is further configured to perform collection and maintenance of cost and consumption of various cloud-computing resources such as CPU-time, storage volume consumption, network I/O and other configurable cloud-computing cost and consumption factors. For example, in some embodiments where the management module accounts for usage of one more cloud-computing services by a client collecting, aggregating and providing this information through a API to customer billing systems while also presenting reporting through the consumption module demonstrating cost and consumption comparisons, projections and usage. Some embodiments may utilize Ariba®, SAP®, or the like to facilitate accounting and billing of usage of cloud-computing service.\n\nIn some embodiments, the build module allows a developer to create a cloud-computing service (e.g., IaaS, PaaS, and SaaS) comprising one or more cloud-computing resources. The build module may utilize build scripts to build a cloud-computing service from one or more cloud-computing resources, configure a cloud-computing service, or publish a cloud-computing service for consumption.\n\nIn various embodiments, a cloud-computing service may be published to a consumption module that allows an end-user to subscribe to the cloud-computing service and utilize the service. In some embodiments, the end-user may access and subscribe to the cloud-computing service through a user interface that lists published and available cloud-computing services. For example, the user interface may be a storefront through which an end-user may preview and select a cloud-computing service for use.\n\nWith some embodiments, an organization can determine the most suitable deployment of a computer workload to a cloud-computing environment, or determine the value/benefit of deploying a computer workload to a cloud-computing environment. For some embodiments, the planning module analyzes a computer workload or workflow that may have previously been on a physical or virtual computing resource and assists in migrating or importing the computer workload or workflow to the cloud-computing environment. In further embodiments, the planning module assesses difficulty in migrating or importing the computer workload or workflow, and the efficiency or value of using the cloud-computing environment. In other embodiments, the planning module determines the correct placement of a computer workload or workflow to an appropriate cloud-computing service based on the profile or characteristics of the computer workload (e.g., determine that the computer workload or workflow needs to be performed within secure cloud/ public cloud/private cloud). For example, for a trading platform, which needs a low latency-computing environment that is secure, an embodiment may recommend placement of trading platform in a cloud-computing service comprising a be used for long-term storage of non-sensitive data, an embodiment may recommend configuration of the platform to use cloud-computing services comprising a public cloud resource, or a combination of cloud and physical resources, such as archival tape storage resources. Further, the placement decision is guided by policy that ensures the cloud-computing resource is placed in the appropriate cloud-computing service.\n\nIn particular embodiments, the system further comprises a policy engine module configured to enforce a policy on the cloud-computing service through the management module. For example, in some embodiments, the management module monitors a cloud-computing resource of the cloud-computing service through the adapter and provisions the cloud-computing resource according to the policy engine module. Additionally, for some embodiments, the management module monitors a cloud-computing resource’s performance using Ganglia Monitoring System or collected (an open source daemon that collects system performance statistics periodically).\n\nIn some embodiments, the system further comprises an identity management module configured to connect to an authentication system and authenticate the user for the cloud-computing service. For example, in some embodiments, the identity management connects to disparate authentication systems (e.g., Netegrity®, Oracle OAM®, Microsoft® Active Directory, RSA® Cleartext, or Light-\nweight Directory Access Protocol (LDAP), Kerberos) to create a federated authentication system that allows unified authentication to a cloud-computing service.\n\nIn various embodiments, the system further comprises an encryption module configured to perform encryption services for the cloud-computing service. For example, the encryption services can include encryption of data on a storage device or data communicated over a network connection. In other embodiments, the system further comprises a connection module configured to securely connect the cloud-computing service to a client network or a cloud provider network. For example, a connection module may be deployed on a client network or a cloud provider network to facilitate a secure network connection between cloud-computing service and a client network.\n\nAccording to some embodiments, a method is provided for a cloud-computing environment comprising a plurality of cloud-computing resources, the method comprising: providing a virtual private cloud configured to utilize a cloud-computing resource from the plurality of cloud-computing resources to perform a computer workload; receiving a request to perform the computer workload within the virtual private cloud, provisioning the cloud-computing resource from the plurality of cloud-computing resources; deploying the cloud-computing resource within the virtual private cloud; and using the cloud-computing resource to perform the computer workload.\n\nAs noted above, the cloud-computing resource may be a virtual (e.g., virtual machine) or physical cloud-computing resource (e.g., dedicated server). For example, the cloud-computing resource may be a virtual computing resource where the virtual computing resource is deployed under control of a virtual machine manager. The cloud-computing resource may be a storage resource, a network resource, an internal private resource, an external private resource, a secure public resource, a platform-as-a-service (PaaS), a software-as-a-service (SaaS), or an infrastructure-as-a-service (IaaS). The cloud-computing resource may be a hybrid cloud-computing resource comprising at least two of a physical resource, a virtualized resource, a private resource, a public resource, an internal resource, or an external resource.\n\nIn some embodiments, the method further comprises receiving a constraint for the cloud-computing resource or for a computer workload that may be deployed on the cloud-computing resource, wherein the cloud-computing resource is a cloud-computing resource; and applying the constraint on the cloud-computing resource such that, when the cloud-computing resource is used to perform the computer workload, the cloud-computing resource's operation is limited according to the constraint. In other embodiments, the method further comprises declaring a static network address for the computer workload.\n\nIn some embodiments, the method further comprises: defining a security zone such that the security zone comprises the virtual private cloud; and applying a security policy to the security zone such that, when the cloud-computing resource deployed in the virtual private cloud is used to perform the computer workload, the cloud-computing resource's operation or the operation of the computer workload is subject to the security policy. The security zone may be defined according to a physical location of the virtual private cloud's usage, a network location of the virtual private cloud's usage, or an attribute of an organization associated with the virtual private cloud. The security policy may be an access policy, a read-permission policy, a write-permission policy, an edit permission policy, a privacy-based policy, a policy regarding a required level or type of encryption, a cloud-computing resource utilization policy, or other policy. The security policy can be configured to only allow software packages that comply with the security zone's policies to be deployed with the security zone. For example, a security zone may be defined as a specified virtual private network (VPN) or a specified physical network of a business enterprise, such that computer workloads being performed by a cloud-computing resource operating in that zone may be modified only by users who have specified authorization credentials issued by that enterprise. Among some embodiments, a security zone may be defined as cloud-computing resources (public or private) that are physically located in a geographical area, such as the United States, allowing a security policy to be applied that prohibits export of data that is to be associated with computer workloads executed in that security zone. In other embodiments, the policies are defined and implemented on the firewalls through a central policy server.\n\nIn additional embodiments, the method further comprises: receiving at a central policy server a definition for a security policy, wherein the central policy server is configured to associate the security policy to the computer workload or to the cloud-computing resource performing the computer workload; and pushing the security policy to the cloud-computing resource.\n\nFor some embodiments, provisioning the cloud-computing resource comprises: locating an unreserved cloud-computing resource within the plurality of cloud-computing resources; and reserving for the virtual private cloud the unreserved cloud-computing resource.\n\nIn embodiments where the cloud-computing resource is an infrastructure element, and the method further comprises: providing a user interface that allows a user to deploy or configure the infrastructure element; setting, through the user interface, a policy to the infrastructure element or to a computer workload that may be deployed on the infrastructure element; and applying the policy to the infrastructure element when the infrastructure element or computer workload is deployed within the virtual private cloud. The method further comprises: determining a reference design for the infrastructure element; and deploying the infrastructure element in the virtual private cloud according to the reference design.\n\nIn other embodiments, the method further comprises: associating a policy with the computer workload to be performed within the virtual private cloud; and applying the policy to the cloud-computing resource performing the computer workload during the computer workload's performance.\n\nIn additional embodiments, receiving the request to perform the computer workload or the application of the policy to the computer workload comprises: receiving an application to be migrated to cloud-computing environment for execution; and identifying the computer workload as necessary for executing the application.\n\nIn further embodiments, the method further comprises: using an adapter to connect the virtual private cloud to one or more other cloud-computing resources, such as of the types described herein; using a metamodel data structure to store an association between a computer workload and a policy; and pushing the metamodel data structure to the adapter such that, when the cloud-computing resource is deployed to perform the computer workload, the adapter applies the policy to the computer workload or to the cloud-computing resource performing the computer workload. In some such embodiments, when a computer work-\nload is moved from using one cloud-computing resource to a second cloud-computing resource, the method may further comprise pushing the metamodel data structure to a second adapter that connects the second cloud-computing resource to the virtual private cloud such that when the second cloud-computing resource is deployed, such as within the virtual private cloud to perform the computer workload, the second adapter applies the policy to the second cloud-computing resource performing the computer workload.\n\nIn other embodiments, the method comprises identifying the cloud-computing resource for performing the computer workload. Identifying the cloud-computing resource may be based on a computer workload score determined by a scoring logic. The scoring logic may be, for example, based on a business attribute of the computer workload, a technical attribute of the computer workload, or an operational attribute of the computer workload. In further embodiments, the scoring logic may include a mix of at least two of a business attribute, an operational attribute and a technical attribute. In various embodiments, the scoring logic may be editable or may be dynamically updated at or near real-time.\n\nIn some embodiments, the computer workload may be scalable. For example, the computer workload may be scaled down to decrease the computer workload’s use of memory and processing time during performance within a virtual private cloud or actually increase or decrease the number of cloud-computing resources which execute the computer workload. In further embodiments, the scaling is based on a policy which may be associated with the computer workload stored in a metamodel, and pushed via an adapter to or among various cloud computing resources.\n\nIn some embodiments, deploying the cloud-computing resource comprises deploying a pre-determined set of cloud-computing resources to optimize the computer workloads’ performance.\n\nIn further embodiments, the method further comprises setting a condition for the computer workload, wherein the condition determines if or when the cloud-computing resource can be deployed within the virtual private cloud to perform the computer workload. According to other embodiments, a method is provided for a cloud-computing environment comprising a plurality of cloud-computing resources, the method comprising: receiving a computing workflow to be performed in the cloud-computing environment; identifying a computer workload to perform the computing workflow; associating a policy with the computer workload; testing the computer workload in a pre-production virtual private cloud (e.g., computing environment) within the cloud-computing environment; deploying the computer workload in a production virtual private cloud (e.g., computing environment) within the cloud-computing environment; and applying the policy to the computer workload during the computer workloads performance within the production virtual private cloud for consumption. In some such embodiments, identifying the computer workload to perform the computing workflow involves identifying a plurality of computer workloads to perform the computing workflow.\n\nAccording to other embodiments, the present invention may provide a method and system for a virtualization environment adapted for development and deployment of at least one software workload, the virtualization environment having a metamodel framework that allows the association of a policy to the software workload upon development of the workload that is applied upon deployment of the software workload. The system and method may allow a developer to define a security zone and to apply at least one type of security policy with respect to the security zone including the type of security zone policy in the metamodel framework such that the type of security zone policy can be associated with the software workload upon development of the software workload, and if the type of security zone policy is associated with the software workload, automatically applying the security policy to the software workload when the software workload is deployed within the security zone. In embodiments, the security zone may be a geographic zone, a network zone, an enterprise zone, an operational zone, an organizational zone, and the like. The security policy may be an access policy, a write-permission policy, a resource utilization policy, an editing permission policy, and the like.\n\nThe security policy may determine whether a software workload is allowed to operate in a specified security zone. The method and system may automatically establish firewall rules across multiple firewalls in multiple security zones for newly deployed applications by tagging application software workloads that are deployed within the security zones. The firewalls may be of types provided by different vendors and employ at least one of different operating system, communication protocols, and programming languages. The method and system may provide an alert when a software workload is planned to be deployed in a security zone in a manner that is inconsistent with at least one of a security zone policy applicable to the security zone and a security policy associated with the workload.\n\nAccording to further embodiments, various operations described above are implemented using a computer. For example, some embodiments provide for a computer program product comprising a computer usable medium having program instructions embodied therein for performing operations similar to those performed by methods according to the present invention.\n\nOther features and aspects of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the features in accordance with embodiments of the invention. The summary is not intended to limit the scope of the invention, which is defined solely by the claims attached hereto.\n\nThese and other systems, methods, objects, features, and advantages of the present invention will be apparent to those skilled in the art from the following detailed description of the preferred embodiment and the drawings. All documents mentioned herein are hereby incorporated in their entirety by reference.\n\nBRIEF DESCRIPTION OF THE FIGURES\n\nThe present invention, in accordance with one or more various embodiments, is described in detail with reference to the following figures. The drawings are provided for purposes of illustration only and merely depict typical or example embodiments of the invention. These drawings are provided to facilitate the reader’s understanding of the invention and shall not be considered limiting of the breadth, scope, or applicability of the invention. It should be noted that for clarity and ease of illustration these drawings are not necessarily made to scale.\nFIG. 1 is a diagram illustrating an example system in accordance with an embodiment of the present invention.\n\nFIG. 2A is a diagram illustrating an example management module in accordance with an embodiment of the present invention.\n\nFIG. 2B is a diagram illustrating an example management module in accordance with an embodiment of the present invention.\n\nFIG. 3 is a diagram illustrating an example of provisioning in accordance with an embodiment of the present invention.\n\nFIG. 4 is a diagram illustrating an example use of a connection module in accordance with an embodiment of the present invention.\n\nFIG. 5 is a diagram illustrating an example use of an identity module in accordance with an embodiment of the present invention.\n\nFIG. 6 is a diagram illustrating an example use of a monitor module in accordance with an embodiment of the present invention.\n\nFIG. 7 is a diagram illustrating an example governor module in accordance with an embodiment of the present invention.\n\nFIG. 8 is a flowchart illustrating an example method in accordance with an embodiment of the present invention.\n\nFIGS. 9A-9D are screenshots of an example user interface in accordance with some embodiments of the present invention.\n\nFIG. 10 is a diagram illustrating an example system in accordance with an embodiment of the present invention.\n\nFIG. 11 is a diagram illustrating an example of an enterprise cloud ecosystem in an embodiment of the present invention.\n\nFIG. 12 is a diagram illustrating an example of a policy-driven governance and control scenario in an embodiment of the present invention.\n\nFIG. 13 is a diagram illustrating an embodiment for a self-service enterprise application store.\n\nFIG. 14 is a diagram illustrating an example of a computing module for implementing various embodiments of the invention.\n\nFIGS. 15-17 are illustrative user interfaces in accordance with the invention.\n\nThe figures are not intended to be exhaustive or to limit the invention to the precise form disclosed. It should be understood that the invention can be practiced with modification and alteration, and that the invention be limited only by the claims and the equivalents thereof.\n\nWhile the invention has been described in connection with certain preferred embodiments, other embodiments would be understood by one of ordinary skill in the art and are encompassed herein.\n\nAll documents referenced herein are hereby incorporated by reference.\n\nDETAILED DESCRIPTION\n\nThe present invention is directed toward a system and method for a cloud computing abstraction layer. Through various embodiments of the present invention, a user can plan cloud-computing services, build a cloud-computing service, publish the cloud-computing service for consumption by users, or run the cloud-computing service. Some embodiments of the present invention provide access to disparate public or private cloud-computing resources through a standard interface. Additionally, some embodiments can apply governance uniformly over disparate public or private cloud computing resources.\n\nSome systems may, for example, enable self-service access to cloud-computing resources by end-users, developers, and admins; automated services with respect to cloud-computing services comprising one or more cloud-computing resources (e.g., management, building, configuration, publication, validation, and building of cloud-computing services); rapid provisioning (e.g., deployment, release, scheduling, control etc.) of cloud-computing resources within a cloud-computing service; governance control of cloud-computing resources within a cloud-computing service (e.g., application of security and non-security policies to cloud-computing resources), audit control of cloud-computing services; or secure access to cloud-computing services.\n\nAdvantages to the present invention's model include enabling a federated constituency of internal and external service providers that can be selected (and switched as needed) to provide best fit and value, such as between different internal and external cloud providers. For example, development projects, which may be subject to waiting times or interruptions, but which contain highly confidential information, may be deployed on a cloud that has low cost, but that has very specific security requirements, while commercial services, some of which are non-confidential in nature, might preferably be deployed on very fast, highly scalable cloud infrastructure to ensure high quality of service, but security requirements might be different than for a development project. A range of factors may be relevant to deployment of a particular project or service (or to a particular workload element related to it), including technical factors (the processing, storage, bandwidth, and other capabilities required to execute a workload), operational factors (such as when and where a workload needs to be available to meet the operational requirements of a business), and business factors (such as anticipated revenues, costs, quality of service requirements, and the like). By enabling federation of services, applications, platform elements, infrastructure elements and the like across multiple types of clouds (including internal and external clouds from varying vendors), while providing a single, unified interface for developing workloads and associating policies relating technical, operational, business and other requirements, the embodiments described herein allow an enterprise to satisfy such requirements much more effectively and efficiently than was possible with prior offerings.\n\nOn top of infrastructure elements provided for a cloud there may be platforms, stacks, software applications, and the like. There may be many different use cases and variations possible in everything as-a-service™ world, such as development and test environments as-a-service, databases as-a-service, platforms as a service, infrastructure as a service, software as a service, and many flavors of each offering different types of services, and the like. Benefits to the federated structure may include greater agility, vendor contestability, and innovation by transitioning an enterprise from a fixed to a variable cost infrastructure (thus avoiding enormous waste currently associated with fixed cost resources acquired by enterprises to meet peak needs but unused in off-peak periods), increased transparency (including the capability to compare the cost, functional benefits, and value of each sub-element of a service, platform, application, or infrastructure component), more direct revenue-to-cost operating models, right-place right size workload placement, minimal vendor lock-in and dependencies, improved standardization, lower risk operating environ-\nments, metered cost savings through \"pay-as-you-go\" economics and demand-driven consumption, faster time-to-market through on-demand provisioning, a compressed systems development life cycle (SDLC), lower costs by arbitrating market price between providers, elastic-dynamic capacity to meet peak demand, and the like.\n\nThe present disclosure also may provide security, governance, and policy enforcement to harness the power and agility of the operating model, a strategy and transition plan to move from a traditional operating model to an everything-as-a-service model, and the like.\n\nFIG. 1 is a diagram illustrating an example system 10 in accordance with an embodiment of the present invention. FIG. 1 illustrates a cloud-computing environment 35 comprising one or more cloud-computing resources, a client network 31 comprising client computing devices 14 (e.g., desktops, laptops, smart mobile devices), and a cloud-computing platform 20 in accordance with one embodiment of the invention. In illustrated system 10, cloud-computing platform 20 provides a system through which computing devices residing on client network 31 (e.g., enterprise network) can access one or more cloud-computing services. A cloud-computing service comprises a cloud-computing resource residing within the cloud-computing environment 35 and managed by the cloud-computing platform to provide the cloud—may comprise one or more cloud providing networks that include cloud-computing resources (e.g., cloud services provided by public or private clouds, which may be external or internal to the enterprise that uses them) that can be utilized by users. Additionally, depending on the embodiment, platform 20 may reside on a client network 31 or separate from a client network 31.\n\nCloud-computing environment 35 may comprise an internal cloud, an external cloud, a private cloud, or a public cloud (e.g., commercial cloud). In the embodiment of FIG. 1, cloud-computing environment 35 comprises internal private cloud resource 38, external private cloud resource 41, and secure public cloud resource 44. A private cloud may be implemented using a variety of cloud systems including, for example, Eucalyptus Systems, VMware vSphere®, or Microsoft® HyperV. Providers of public clouds may include, for example, Amazon EC2®, Amazon Web Services®, Terremark®, Savvis®, or GoGrid® Cloud-computing resources provided by these clouds may include, for example, storage resources (e.g., Storage Area Network (SAN), Network File System (NFS), and Amazon S3®), network resources (e.g., firewall, load-balancer, and proxy server), internal private resources, external private resources, secure public resources, infrastructure-as-a-services (IaaSs), platform-as-a-services (PaaSs), or software-as-a-services (SaaSs).\n\nBy using cloud-computing platform 20 to plan, build, manage, or use cloud-computing resources within a cloud-computing environment, users of platform 20 are provided with standardized access to a variety of cloud-computing resources from disparate cloud-computing systems and providers without concerning themselves with the proprietary details of accessing or interfacing with such cloud-computing systems and providers. The platform 20 is configured to take the workloads that are developed with the platform 20 (as more particularly described throughout this disclosure) and automatically provide the interfaces and access steps necessary to operate the workload on any particular platform or infrastructure element within a federation of cloud computing resources, such that the user is able to interact with the platform to develop such workloads at a level of abstraction that allows the user to configure the logic of the workload (including conditional logic that allows interrelation of different workloads) and to embody the technical, operational, and business requirements of the workload in policies that are associated with the workload, without the user being required to access or understand the details of (or in some cases even know about the existence of) such particular platform or infrastructure elements. Additionally, users of platform 20 can access cloud-computing services through platform 20 on-demand and on a self-service basis through the standardized access. Users of cloud computing services offered by platform 20 may include end-users, developers, partners, or administrators that reside on the client network 31.\n\nPlatform 20 may comprise planner module 23, manager module 26, builder module 29, and consumption module 32. Planner module 23 is configured to plan cloud-computing service provided by platform 20 by inventorying, profiling, characterizing and prioritizing computer workloads, such as programs, applets, calculations, applications, servers, or services. For example, with respect to software/application development, planner module 23 may model current applications and associated software-development life cycle (SDLC) phases to determine what infrastructure environments would be required or preferred. This may include defining security, privacy, management or other profiles for each SDLC phase of each application. The profiles, in turn, will identify existing infrastructure and systems that support the SDLC phases, and manage relationships between the infrastructure, systems and the applications. Profiles may also contain characteristics regarding the SDLC phases or attributes relevant to development, deployment or performance of infrastructure, systems, or workloads, such as latency, geography, responsiveness, bandwidth, storage capacity, processing speed, processing type, platforms involved (including operating system, file types, communication protocols, and the like), data involved, protocols used, and specific institutional requirements. In terms of prioritizing the cloud-computing services needed for the SDLC phases, planner 23 may first identify which SDLC computing environments and systems would be suitable for cloud computing or migration to cloud computing, and then prioritize the enablement and operability of newly developed or migrated computer workloads according to the SDLC phases. Subsequently, the characterizations determined by planner module 23 can be used by builder module 29 to build a cloud-computing service or to deploy a computer workload to a cloud-computing resource. In the planner module 23 or in other components of the platform 20 associated with the planner module 23 the user may have access to, or may create or modify, policy information relevant to the computer workloads with which the user can interact in the planner module 23. The policy information may be stored in or associated with a meta model, which may enable the identification, characterization, and storage of a wide range of information, including policy information, that can be associated with a given workload. The metamodel data, including policy information, can be associated with the workload such that throughout the various components of the platform 20, from planning through deployment to a cloud, the workflow can be handled in a manner that is consistent with the metamodel data, and in particular consistent with the policies that are applicable to that workload. In the planner module 23 the planner/user may thus plan the use of workloads in a manner that is consistent with technical, operational, and business requirements that are appropriate with such workload, as seen by association of the same with the workload, and the planner/\nuser may modify or populate the policies associated with the workload, such that the metamodel data for that workload embodies and is consistent with the plans of the planner/user. Once associated with the workload, such policies and other metamodel data are stored by the platform 20 and may be used throughout the development and deployment cycle.\n\nBuilder module 29 may be configured to assemble, validate, and publish a cloud-computing service or computer workload for consumption (i.e., use) by a user. Builder module 29 may be configured to receive characterization information from planner module 23 and build a cloud-computing service or computer workload based on the information. For example, builder module 29 may be configured to assemble a cloud computing service based on the prioritized list of computer workloads provided by planner module 23. Builder module 29 may be configured to create and edit scripts for loading computer workloads during installation, startup, runtime, and shutdown of cloud-computing services assembled by builder 29. The scripts for the cloud-computing services may be verified and validated before the cloud-computing services are published for consumption (i.e., use). The script may have access to metamodel and policy information which may alter how the script utilizes the metamodel and policy information to make a decision. Additionally, builder module 29 may be configured to associate the computer workload with the appropriate cloud-computing service or resource (e.g., associate an application with an appropriate virtual machine image or associate a computer workload with a specific network). As with the planner module 23, in the builder module 29 the user/builders may have access to, or may create or modify, policy information relevant to the computer workloads with which the user can interact in the builder module 29, such as the policy information stored in or associated with the above-referenced meta model, which may enable the identification, characterization, and storage of a wide range of information, including policy information, that can be associated with a given workload. In the builder module 29 the builder/user may thus build of workloads in a manner that is consistent with technical, operational, and business requirements that are appropriate with such workload, as seen by association of the same with the workload, and the builder/user may modify or populate the policies associated with the workload, such that the metamodel data for that workload embodies and is consistent with the plans of the planner/user. In embodiments, the builder module 29 may present options to the builder pre-filtered, such as in pre-populated scripts, filtered drop-down menus, that are dictated by or consistent with the policies and other metamodel data associated with a workload, omitting, blocking or hiding options that are inconsistent with such policies. For example, a workload that stores customer data could omit the option to store a social security number if a data privacy regulation prohibits storing such data in the business process to which the workload relates. Such automatic pre-filtering, pre-configuration, and blocking ensure consistency with the policies associated with the workload at the planning stage (or other stages) while also improving efficiency by removing development paths that might be pursued despite being prohibited. In embodiments, the metamodel provides a flexible structure to organize metadata and apply the same policies using a combination of system and user supplied metadata that may indicate use of the same policy, however may define the same policy in different ways. For example, in some embodiments, the system may consider a Tier 5 datacenter to be the most fault tolerant type of data center and a user may consider a Tier 1 data center to be the most tolerant. The metamodel allows a policy that requires provisioning in the most fault tolerant data center to be assigned Tier 5 or Tier 1 metadata, depending on the definition of the most fault tolerant data center in that specific operating environment.\n\nEventually, builder module 29 can publish a cloud-computing service for consumption by users. In some embodiments, the build module 29 will publish the cloud-computing service to a consumption module 32 (e.g., store or storefront such as an application store, a service store, or a software stack store) where users can preview, select, and subscribe to a cloud-computing service for use. Further, in some embodiments, the builder module 29 will enter the cloud-computing service in repository 30 when it is ready and available for consumption by users. Embodiments may also be configured the builder module 30 such that the development community can approve or disapprove of the cloud-computing service before publication.\n\nConsumption module 32 is configured to allow a user to subscribe to, collaborate on, and assess a cloud-computing service published for consumption. For example, a user can preview cloud-computing services available for deployment to the virtual private cloud and consumption. Then, when a user wants to subscribe and invoke a cloud-computing service for usage, the user can invoke the cloud-computing service on a self-service, on-demand basis through the consumption module 32. Consumption module 32 may list published available cloud-computing service at or near real-time, and allow a user to request updates and information on a listed cloud-computing service. In some embodiments, the consumption module 32 may allow users to collaborate on where, what, and how many cloud-computing services are deployed for consumption. In further embodiments, consumption module 32 may allow a user to comment on and rate cloud-computing services, or assess the cost associated with deploying and using a cloud-computing service. As noted above, as with the planning module 23 and the builder module 29, the consumption module 32 has access to policy information and other metamodel data that is associated with each workload, such that the workload may be consumed only in a manner that is consistent with such policy information. Thus consumption policies related to permitted time, permitted sets of users, security, pricing, resource consumption rules, and a wide variety of other policies may be maintained by the consumption module 32 and the policies associated with the workload in the platform 20.\n\nManagement module 26 is configured to provision one or more cloud-computing resources for a cloud-computing service or computer workload, manage one or more cloud-computing resources for the cloud-computing service or computer workload, and monitor one or more cloud-computing resources for the cloud-computing service or computer workload. For example, manager module 26 may provision one or more cloud-computing resources (e.g., provision one or more virtual machine instances) for a published cloud-computing service that is invoked from the consumption module 32. Upon invoking the cloud-computing service, the manager module 26 may deploy and start the one or more cloud-computing resources to the virtual private cloud for the cloud-computing service.\n\nWith respect to control, manager module 26 may control the start, stop, or run-time of one or more cloud-computing resources (e.g., control start, stop, or run-time of virtual machine instance) for a cloud-computing service. Manager module 26 may further schedule the start and stop time windows for the one or more cloud-computing resources, or\ngovern a service level, such as per a service level agreement (SLA), or a threshold associated with the one or more cloud-computing resources. Through its control, manager module 26 can govern the cloud-computing resource according to conditions, constraints, security policies, or non-security policies. Manager module 26 may also monitor the one or more cloud-computing resources, detect security intrusions, and monitor the consumption of cloud-computing services their associated cloud-computing resources in order to determine the costs accrued by a user. Aspects of cloud-computing resources monitored by manager module 26 include, for example, central processing unit (CPU) usage, memory usage, data storage usage, data input/output usage, application usage, workload usage, service usage, and other attributes of usage of a service or a computer workload.\n\nIn some embodiments, manager module 26 is configured such that a user can request a planer using the planner module 23 to change the design of a cloud-computing service. For example, a user may request that the cloud-computing service change one or computer workload with respect to the cloud-computing resources utilized (e.g., change to a platform stack). As in the other components of the platform, the manager module 26 has access to, or may create or modify, policy information or metamodel data relevant to the computer workloads with which the user can interact in the manager module 26. The manager/user of the manager module 26 may thus manage the provisioning of infrastructure and platform elements such that usage will be consistent with the policies of the enterprise, including operational and business policies, as well as technical requirements. For example, provisioning to expensive infrastructure elements may be confined to workloads that satisfy business rules that distinguish between mission critical elements and other elements. The manager/user of the manager module 26 may be provided with access to the policies consistent with the metamodel framework, and in embodiments may be provided with pre-filtered options, such as in menu choices, decision trees, or the like, that are consistent with such policies. For example, a workload designated as non-critical in its metamodel data could automatically appear in the manager module with deployment options confined to relatively low cost clouds, while a mission-critical workload might appear with all different cloud options (or ones that are filtered to satisfy certain requirements as to low latency, bandwidth, storage capacity, guaranteed quality of service, or the like). As with other modules, the manager module 26 may thus enforce policy while streamlining workflow, improving both effectiveness and efficiency.\n\nFIG. 2A is a diagram illustrating example management module 26 in further detail. As illustrated, management module 26 comprises governor module 103 configured to govern operation of a cloud-computing service and its associated cloud-computing resources, provisioning module 106 configured to provision cloud-computing resources for a cloud-computing service, and monitoring module 112 configured to facilitate the various monitoring functions of management module 26.\n\nIn embodiments, the present invention may provide for a policy-driven infrastructure as a service (IaaS) event bus, which is comprised of a policy engine, metamodel, reporting system, and workflow engine; and allows for the creation of business policies, such that said business policies can be reflected into a dynamic information technology environment and expressed across internal and external information technology infrastructure, regardless of operating system, provider, by making use of abstraction layers. The workflow engine provides an integration point between the IaaS event bus and workflow management, as described elsewhere in this specification. The abstraction layers allow for integration with application programming interfaces made available by different vendors, business models, technical models, eventing and alerting channels and monitoring systems in a vendor agnostic manner. In embodiments the abstraction layer could be a cloud-computing provider. A cloud computing provider may be VMware, BareMetal, Amazon EC2, SaviT, TerMark, Microsoft HyperV, and the like. In other embodiments, there may be multiple layers of abstraction in an abstraction layer.\n\nThe policy engine allows policies to be created through an easy to use visual interface that allows users that do not necessarily have information technology skills or other programming skills to author and assign policies to workloads. The policies can be expressed via languages such as XML, and the like. In some embodiments of the present invention a policy could be an event policy. An event policy supports matching one or more events that are temporally related and generate a notification action when matches occur. An event can be defined as either a threshold condition or matching constraints specified as rules. A rule is comprised of one or more match constraints and each match constraint must be satisfied, by a logical “and” operation, within a specified sliding time window in order for the notification actions to be invoked. A match specifies the set of conditions that must be satisfied to match an event. Each condition specifies a property of an event or object contained by the event, which is matched against a set of one or more values using the supplied comparison operation. If multiple values are supplied for a condition then the result is a logical “or” operation of the property being compared and against each value individually. Any of the event properties or properties of objects contained within the event structure may be used to refine the match criteria. For example, an auto-scaling policy may be created to add more web and database servers according to a ration if a business application becomes heavily loaded, in order to reduce the load on that application. In another embodiment, an auto-scaling policy with business awareness may be created that deploys additional business topologies according to an algorithm if revenue per hour exceeds a threshold.\n\nThe metamodel allows the system to abstract business user definition from technical definition and allows an enterprise to track information about information technology resources that were unknown when the system was created. By abstracting the business user definition from the technical definition, the metamodel allows businesses to define data classes consistent with their enterprise nomenclature, while still being able to map them consistently to the internal system. For example, a Tier 4 data center is common technical classification of a data center that generally has the highest uptime, however some enterprises refer to Tier 4 data centers as Tier 1 and the metamodel would allow Tier 1 and Tier 4 to be used interchangeably, depending on the definition used by a specific enterprise. This provides a benefit to the enterprise by eliminating the need to write specific policies for each instance or the need to customize each abstraction layer for individual instances. By tracking information about IT resources that were unknown when the system was created, the metamodel allows business users to arbitrarily define elements of data to track and create policy after the system was built, also allowing the users to track a specific piece of information that is defined for any resources that are managed by the system. Resources could\nbe networks, storage, servers, workloads, topologies, applications, business units, and the like.\n\nIn other further embodiments, the policy-driven infrastructure as a service may also include additional components. Additional components may be reporting, auditing, and federated identity management systems.\n\nIn embodiments, the present invention may provide for a visual policy editor, which provides an easy-to-use graphical user interface to a feature-rich and extensible policy engine, using a visual programming language and policies, eliminating the need for the user to write complex code to define, assign, and enforce policies. The graphical user interface allows the user to author policies using a visual drag-and-drop interface or an XML editor. The visual programming language functions could be loops, variables, branching, switching, pulling of attributes, code execution within a policy, and the like. For example, the visual programming language could access an external pricing engine that contains live pricing information, then make a decision on the next step of the execution process, based on the information it receives from the pricing engine. In some embodiments, policies can be enforced at an object level. Objects could be organizational groups, individual projects, different deployment environments, and the like. Policies could be access control policies, firewall policies, event-based policies and the like. Access control policies could include packages, scripts, and the like. Access control policies could be defined by cloud or other service providers, network attributes, network geographic location, security policies, and the like.\n\nFirewall policies may include port and network ACL lists that are applied as policies and applied at container level to ensure conformance to corporate standards for port opening/closing. Event-based policies relate to service level management and could include compound threshold rules that trigger an action, lifecycle event management, compound event sequences, signature detection, and policy stacking, and the like. For example, a policy could be defined to restrict deployment of a computing workload to private internal clouds in a specific country.\n\nIn embodiments, the present invention may provide for automated processes to support a continuous integration cycle to migrate a computing workload from a development environment to an operational environment. The continuous integration cycle may include maintaining a code repository, automating the build process, self-testing the build process, automatically deploying the build, and the like. The policies and metamodels defined and assigned to the computing workload environment follow the build from its creation using the Builder Module through to its publication into the Consumption module. This capability allows the enterprise to greatly reduce the time required to develop, test, deploy and update a computing workload. Continuous integration may also include ensuring the modernization, patch management, conforming configuration of deployed cloud-computing services. The embodiments may provide this service as DevToOps policy allowing centrally defined service definition that deployed cloud-compute services can compare against and either update themselves when their configuration no longer matches, warn administrators of non-conformance, rewrite themselves back to conformance when configurations of the cloud-compute services are made arbitrarily, and the like.\n\nAs noted before, various embodiments of the present invention provide standardized access, management, or control to different types of cloud-computing resources on a self-service, on-demand basis without the user needing to know the specific instructions or details for accessing, managing, or controlling those different target cloud-computing resources.\n\nIn order to translate a standard management action for a cloud-computing service to instructions for its cloud-computing resource and/or instructions for a computer workload to be executed on a cloud-computing resource, some management modules may comprise a cloud model data store that maps the management action to the appropriate cloud-computing resources. Subsequently, the management action is translated to one or more instructions for a target cloud-computing resource and/or a computer workload operating thereon. For example, a topology is an example of a cloud service, where a topology is comprised of a number of individual virtual machines orchestrated together. A common management action to perform on a topology is to start it. This simple topology start action within the management layer gets turned into a number of individual instructions that get passed down into the cloud service bus, such as (1) calculate the Start Up order for topology, (2) initiate ordered startup one VM at a time, (3) as VM's come up, attach volumes that are associated with the VM, (4) install any packages and software onto the VM's, and (5) once all machines are up and running the topology status changes to running.\n\nCloud service bus may be utilized to parse management instructions received from the manager module to transform the management instructions to instructions compatible with the target cloud-computing resource, and route the management instruction to the targeted cloud-computing resource. In some embodiments, the cloud service bus then routes the instructions to the application program interface (API) for a target cloud-computing resource from external commercial cloud resource, or to the virtual machine manager (VMM) or hypervisor for a target cloud-computing resource from internal private cloud resources.\n\nFIG. 2B illustrates an example flow of management instructions from manager module to a commercial cloud API. As illustrated in FIG. 2B, provisioning module of management module transmits a management action for a cloud-computing service currently deployed within a virtual private cloud (VPC) or a cloud computing resource to be deployed in the virtual private cloud. Cloud service bus receives the management action, parses the action, and utilizes cloud model data store to resolve the action to the appropriate one or more cloud-computing resources associated with the cloud-computing service. These management actions are then translated to target-specific instructions (e.g., commercial hypervisor API calls) by a target-specific adapter that connects one or more cloud-computing resources to one or more other cloud-computing resources or to the cloud-computing platform. Given the disparate types of cloud providers and systems that exist, each having a proprietary interface for access, management, and control, some embodiments utilize a target-specific adapter in order to connect to and interface with cloud-computing resources provided by those different cloud providers and systems.\n\nIn the illustrated embodiment, once target-specific instructions have been determined, cloud service bus routes the instructions to the Amazon EC2® adapter, which transforms (221) (or translates) the management action to one or more target-specific instructions that are routed to the Amazon EC2® API for execution on the Amazon EC2® cloud-computing environment. Other adapters illustrated include Microsoft® System Center Virtual Machine\nManager, a VMWare(R) adapter, a RackSpace(R) Adapter, and a Sun(R) VMOpsCenter Adapter. Other APIs illustrated include the Citrix(R) XenCenter(R) API 122 used to interface with a XenCenter cloud-computing environment 128, or a Sun(R) xVMCenter API 123 used to interface with the xVMCenter cloud-computing environment 129.\n\nIn some embodiments, the instruction is transmitted to the Amazon EC2(R) API 203 through connection module 118, which implements a secure (i.e., encrypted) connection between the platform and the cloud-computing environment, the platform and client network, or the cloud-computing environment and the client network to ensure secure communication between the platform and environment. Connection module 118 may utilize, for example, when a cloud-computing environment does not provide a secure connection between a client and its cloud-provider network (e.g., a commercial cloud provider does not provide a secure connection as feature of their cloud services). Additionally, connection module 118 may be deployed and utilized on the client-side network when the client lacks a secure connection with the platform.\n\nFIG. 3 provides a diagram illustrating an example of provisioning an embodiment of the present invention. As illustrated in FIG. 3, upon receipt of a provisioning request from a virtual private cloud (VPC) user interface 256, (asset) repository 262 is queried to extract all relevant metamodel information for the deployable assets (e.g., cloud-computing resource), such as a cloud-computing service having a specific topology. A simple topology may comprise a single cloud-computing resource (e.g., operating system running on a virtual machine) or a single tier of cloud-computing resource instances (e.g., LAMP server), combined to provide a cloud-computing service such as a web front-end. A more complex topology may comprise more than one tier of related cloud-computing resource instances such as a back-end database service tier, middleware tier, and web front-end tier, each tier performing a related service as part of delivery of an application to a set of users. The cloud model 109 is queried 280 to match the type(s) of cloud-computing resource instance with an appropriate provisioning request.\n\nUpon successful match, a policy management engine within governor module 103 is queried to ensure current policies allow for provisioning the cloud-computing resource from a cloud-computing environment, thereby providing “valid” or “right” placement 283, consistent with the handling of policy and the metamodel framework described above and throughout this disclosure. Topology interpreter 271 examines the request for the relationships of the cloud-computing resource instance(s), being requested and the access list (network port) assignments for the instance(s), and then passes the information to provisioning agent 274. Provisioning agent 274, in turn, queues the startup requests for the cloud-computing resource instances based on the defined startup order of the topology and provisions the instances and access list requests 289 through the virtual machine manager (VMM) API.\n\nFIG. 4 is a diagram illustrating an example use of a connection module 118 in accordance with an embodiment of the present invention. Specifically, illustrated are two cloud-computing environments 306 and 309 each running instances of either Microsoft® Windows (333) or a distribution of Linux (339). Each cloud-computing environment is configured with a cloud firewall (315, 318) that blocks specified network traffic and defends the environments against malicious network traffic.\n\nIllustrated opposite the cloud-computing environments is client network 303 (e.g., enterprise network) that has an instance of Linux 342 and Solaris (times.86) operating and is equipped with it is an enterprise firewall 312. In order for the cloud-computing environments (306, 309) to communicate with client network 303 over external network 321 (e.g., the Internet), connection modules (324, 327, 330) are deployed on the three entities in order to establish and maintain encrypted communication tunnels (346, 351) between the cloud-computing environments (306, 309) and the client network 303. In addition, connection modules (324, 327, 330) establishes these encrypted communication tunnels (346, 351) through allowed ports on the firewalls (312, 315, 318). In FIG. 4, the connection modules (324, 327, 330) establish one encrypted tunnel for management (351) and another encrypted tunnel for data (346). The Platform 20 may support this concept in a plurality of ways. For instance, the platform 20 may have the capability to deploy what is commonly referred to as a VPN Overlay network. This network creates secure communication channels between two endpoints. In this instance, the network is setup by deploying “connection modules” into each of the different environments. The connection modules create secure connections between each other. Now when guest machines are created, they are configured to VPN into their appropriate connection module. From that point on all traffic is tunneled through these secure endpoints and traffic can be routed across network segments (i.e. in between cloud providers and on premise). In another instance, a connection broker may rely on creating IPSec tunnels between individual cloud providers and on-premise environment. This allows for traffic to traverse from one cloud environment to another via your own internal networks.\n\nFurther, the solution may be configured to combine a set of firewall configurations to enable a security zone model. Specifically as a new virtual machine is brought online the system can reach out to all the relevant firewalls and set up the appropriate communication. This can mean that the system will configure a host based firewall on the VM, a hypervisor firewall the VM is running in, physical firewall devices, and other firewalls such as the host or hypervisor firewalls running on any of the machines in the communication channel. This could mean that starting a VM will result in hundreds of firewall changes across the spectrum of all firewall devices and services that might be in the communication path.\n\nIn embodiments, the platform 20 may provide for end-to-end security across internal and external clouds, such as including secure data in transit from the platform to external clouds, secure access for users, secure encryption keys, secure logs for auditing, secure instances from breaches, secure data in storage, and the like. The platform may provide for comprehensive security capabilities designed for agile IT operating models, such as for network security, instance security, data security, access security, and the like. For instance, network security may include an encrypted overlay network across multiple clouds and enterprise data centers, firewall integration with support for multicast, static IP management, point-to-point routing, and the like. Instance security may include images with pluggable host-based intrusion detection systems and virus scanning, and the like. Data security may include images that utilize configurable encrypted block storage as well as SDKs for non-block storage requirements, and the like. In embodiments, access security may include federated identity management and granular role-based access control to instances and stores. For example, there may be need to store creden-\nCommercially significant data and credentials in a third-party encrypted key-store. The platform may allow for storing of all credentials in its own encrypted key-store or the ability to store in third-party FIPS compliant key-store for added security and compliance.\n\nIn embodiments, the present invention may provide for a secure federation of internal and external cloud providers to operate as a trusted extension of an enterprise, establishing security policy and governance earlier in the lifecycle, combined with automated policy enforcement, to provide a more secure computing environment than previously available. Comprehensive security may include host intrusion detection systems and anti-virus protection, virtual firewalls, encryption of persistent data, secure connectivity, federated identity management, and the like. Network isolation may be provided to include a redundant customer-controlled encrypted overlay network service that provides security in a cloud across multiple clouds and between enterprise data centers and commercial clouds; support multicast, static IP management, point-to-point routing, firewall integration; and the like. Instance isolation may be provided through stacks including active host based intrusion detection and prevention packages; pluggable virus scanning integrated into each stack; and the like. Data isolation may be provided, such as including a configurable encrypted block storage system, as well as SDKs for non-block storage requirements; backups of block storage devices including encryption; configurations for encryption of data to be transferred or stored in non-block storage, a cloud manager providing granular role-based access control to instances and stores; and key-pair access control of instance log-in, such as connections only over strong-encryption SSL; and the like.\n\nIn an embodiment, an overlay network may extend the client’s network into the cloud provider, such as through bridges to corporate network (e.g., like VPN); enhanced failover, load balancing, and peering; support extension of corporate IP assignments (e.g., both DHCP and static); support for point-to-point connections (e.g., servers that can talk directly to each other without having to go back to corporate data highway; ability to bridge multiple clouds; support for multicast; deployment of nodes in both the external cloud provider and the corporate data high; and the like.\n\nEach of the security capabilities described herein may be provided for a particular platform or infrastructure network, as applicable, or may be applied across a security zone, as noted above, such that the security zone, which may reside across multiple clouds or networks, is maintained as a defined layer of security for all elements with the zone. Thus, security policies applicable to the zone may, by being associated with all workloads in the zone, be enforced to ensure that all security policies are deployed, executed, and consumed in a manner consistent with the current security policies for the zone. The boundaries of each security zone and policies can be rapidly and conveniently updated, such as in the manager module, with assurance that all workloads within the zone will be provided with updated policies, as applicable, and that they will be handled consistent with such policies. As noted above, multiple security zones may be defined at differing levels of abstraction, such as geographic, business unit, user type, physical network, cloud, cloud type, or the like. Workloads in each zone will be required to satisfy the security policies of the zone, such that if a workload is deployed within overlapping zones, it will be subject to all policies for all such zones. For example, a transactional workload might have a security policy defining anti-virus requirements based on its presence in a security zone defined by the business unit that handles that transaction, but it might also be subject to data encryption requirements defined for a security zone defined by the legal department for all business units of an enterprise. The platform may include the capability to view, manage, and edit security policies for security zones, including to highlight and resolve any potential conflicts among policies in the case of overlapping zones that apply to a workload. The ability in the platform to plan, design, rapidly deploy, and manage workloads and related policies that comply with varying and overlapping security zones allows efficient satisfaction of constantly changing technical requirements (e.g., based on the latest anti-virus, firewall, and similar capabilities for a particular type of cloud or other infrastructure resource), shifting regulatory requirements (such as satisfying legal requirements for security of private user data), and shifting business requirements (such as providing security features that satisfy customer preferences as to security and conformance of use). Among other capabilities, the definition of security policies in the platform at a level of abstraction that is independent of the infrastructure and platform elements on which a workload is deployed allows an enterprise to establish security zones that are vendor independent. A single security zone can have a defined policy, such as to satisfy a legal requirement, that is associated with a workload, and that is applied within a security zone that contains firewalls, routers, storage systems, and other elements that come from disparate vendors. The platform automatically parses the policy and metamodel data associated with the workload and ensures that the infrastructure elements, regardless of type, are provisioned, updated, and operated in accordance with the policy. This capability allows the enterprise to avoid a great deal of effort, often unsuccessful due to the time required and the rapidity of shifting requirements, that has previously been spent analyzing, discussing, and updating security policies, then configuring a host of disparate devices in an effort to comply with the changing policies.\n\nIn some embodiments, the method further comprises: deploying an application, where the application is associated with one or more computer workloads; and where each application and/or computer workload is assigned a security zone; and tagging each application or computer workload based on its security zone such that firewall rules permit the application to perform the computer workload are automatically and simultaneously applied to multiple firewalls within and outside the security zone assigned to the application. In some embodiments, the application may have complex security policies integrated within it during the development process of the application. Each application or computer workload may be tagged to operate in a specific security zone and communicate across security zones and each security zone may have a defined set of firewalls associated with it. In some embodiments the firewalls may be virtual firewalls or physical firewalls. In some embodiments, the firewalls may be provided by multiple vendors such as Cisco, Juniper, and the like. In some embodiments the firewalls may be cloud-based firewalls provided by vendors such as Amazon, VMWare, and the like. For example, a database application that is tagged to operate in a highly secured security zone may require connectivity through a built-in firewall on the database server, a firewall upstream of the server between the highly secured security zone and a less secure corporate network security zone, and a firewall between the less secure corporate network security zone and a security zone that connects to the public Internet.\nAn adaptor automatically determines the IP addresses assigned to each of the firewalls required to permit the application to perform the computer workload; and simultaneously on each firewall establishes rules required by the application, without restarting the system in which the firewall(s) operate. In other embodiments, the method further comprises removing the firewall rules when the application or computer workload is removed or stopped.\n\nAs noted before, connection modules such as those illustrated may be utilized when a secure connection is not readily available between a cloud-computing platform of an embodiment and a cloud-computing environment, between the cloud-computing platform of the embodiment and the client network, or between the cloud-computing environment and client network.\n\nFIG. 5 is a diagram illustrating an example use of an identity module in accordance with an embodiment of the present invention. In FIG. 5, enterprise network 406 is illustrated comprising identity module 29 in accordance with an embodiment, and identity store 415. Illustrated opposite the enterprise network is a cloud provider network 403 that is providing commercial cloud 409 (e.g., cloud-computing resource for a cloud-computing service) to enterprise network 406.\n\nIdentity module 29 facilitates identity provisioning and de-provisioning 418 (e.g., sign-on and sign-off) of a user to a service provided on a public (e.g., commercial) or private cloud. In some embodiments, identity module 29 performs this service by authenticating the user using the client’s authentication system (i.e., identity store 415). For example, identity module 29 may authenticate a user using a locally deployed service, such as Netegrity®, Oracle OAM®, Microsoft® Active Directory, RSA® Cleartrust, Lightweight Directory Access Protocol (LDAP), and Kerberos. For instance, in one use case the platform 20 could be configured to use Active Directory (AD) as its user store. When a user wishes to console or desktop into a Virtual Machine that exists within a cloud environment, they may be prompted for credentials. The user supplies their credentials and the platform authenticates against AD. If there is a match, the platform 20 may log into the VM as Admin and create a new local account for the user based on the AD credentials. The user can now login to the VM. Another use case may deal with Software as a Service Integration, where a store, as described herein, may include the concept of purchasing user seats with cloud-based services, such as the commercially available service Salesforce. When a user, backed by the user’s AD identity, orders a Salesforce user seat, the platform may provision an account for the user within portfolio of an enterprise, the platform may de-provision the user account within Salesforce. Users may also have the option to \"consume\" Salesforce, which redirects the user to Salesforce and performs SSO. In another example, a user logs into the platform to access a Salesforce service, where first the user is authenticated (e.g. via AD, Netegrity), then based on his identity the platform 20 checks to see if the user has an account in Salesforce. If not, the system may create one in Salesforce by calling the Salesforce account management APIs. The system may also look up additional information about this user by doing database queries or other types of lookups against internal systems. If a user tries to access the service and the system detects the user should no longer have access (e.g. because the user has been terminated for example), then the platform 20 will initiate a process to delete the account and clean up all relevant data. This detection and cleanup process could also be initiated by a periodic job that gets run automatically by the platform 20 according to a schedule, by detection of events (such as changes made to AD), and the like.\n\nIn some embodiments, once a user is successfully authenticated using identity store 415, identity module 29 redirects that user’s credentials to the cloud-computing service for authentication. Once the cloud-computing service successfully authenticates the user based on the forwarded user credentials, the user is redirected to the logged in cloud-computing service. It should be noted that identity capabilities may be applied to a cloud-computing resource as well as to a user, such that a specific cloud-computing resource may be authorized (based on its identity) to be used in connection with execution of a computer workload.\n\nFIG. 6 is a diagram illustrating an example use of a monitor module in accordance with an embodiment of the present invention. As illustrated, governor module 103, monitor module 112 and private internal clouds 530 reside on enterprise network 503. Commercial clouds 512 and 515 are providing cloud-computing resources to the enterprise network 503. Monitor module 112 is responsible for monitoring the status and utilization of commercial clouds 512 and 515, and deploy a monitor collector 506 and 509 to the commercial clouds 512 and 515 to collect and transmit such information to monitor module 112. The collectors may provide a plurality of functions. For instance, the first thing a collector may do is collect information coming from the guests. The collectors may also persist this data and respond to queries about the data from the main Monitor Module. Being able to deploy these remote monitors provides many benefits, such as lowering bandwidth costs due to all of this data not having to be sent across WAN links (e.g., the data stays on the collectors, and is only retrieved when a specific query needs it), increasing scalability where each collector node can handle a large number of guests and as the number of guests increases additional collectors may be deployed to handle the load, and the like. In another instance, a deployed VM (e.g. to a VM of an Amazon cloud) may periodically report back its status as well as a set of performance metrics it was seeing. Based on this, the platform could detect if there was an outage at that VM. It could detect this as soon as a machine reported, or if a machine fails to make a schedule report. The monitoring system may be able to monitor events above and at the hypervisor. That is, the monitoring system may receive data not only from VMs, but that it may also be extended to call the low level APIs and metric systems of the hypervisors and cloud computing services and aggregate data from both locations to provide a holistic picture of the performance and status of the system.\n\nAggregator 518 receives the information from individual monitor collectors (506, 509) and monitor collectors (not shown) deployed to private internal cloud 530, and records the (received) monitor information for governance purposes, provisioning purposes, or administrative purposes (e.g., event reporting). Monitor module 112 uses translator 521 to interpret the monitor information from the commercial clouds (512, 515) and relays (524) the interpreted monitor information to event console 527. Aggregator 518 also forwards monitor information to governor module 103 to enable the module to govern the operations of cloud-computing resources and cloud-computing services being managed by a cloud-computing platform in accordance with an embodiment. The monitor and collector modules may all reside inside the Enterprise Network 503 as virtual appliances running within the internal virtualized Enterprise Network 503 compute environment.\nFIG. 7 is a diagram illustrating example governor module 103 in accordance with an embodiment of the present invention. Governor module 103 applies constraints, conditions, non-security policies, and security policies on cloud-computing resources and cloud-computing services being managed by a cloud-computing platform in accordance with an embodiment. In the illustrated embodiment, governor module 103 governs the cloud-computing resources and services by using monitoring information (from cloud-computing resources) provided by monitor module 112, and then issuing management actions (e.g., VPC actions) to cloud-computing resources based on monitoring information and the constraints, conditions, and policies the governor is applying to the cloud-computing resources.\n\nIn order to apply the constraints, conditions, and policies, governor module 103 uses analytics engine 609 to analyze monitoring information from monitor module 112 and, then, uses the analysis information to apply the constraints, conditions, and policies through policy engine 603. Based on the application of the constraints, conditions, and policies, policy engine 603 issues actions to 606 to issue management actions to provisioning module 106 (e.g., issue management actions to increase or decrease the number of cloud-computing resources based on CPU utilization of the existing resources). For instance, when a new threshold policy gets created the threshold may be pushed down into the analytics engine. The analytics may be continuously evaluating the flow coming in from the monitor modules and evaluating the flow against its threshold definitions. When a threshold is violated an event may be created and sent to the policy engine. The policy engine may then determine which action to take and pass the instruction off to the action engine. In the case of auto-scaling the action engine may pass a provisioning or de-provisioning request to the provisioning module.\n\nIn embodiments, the flow amongst the monitor and provisioning modules and the analytics and policy engines may be as follows. In step 1, the Monitor Agent may collect data in a variety of ways including polling the system for status, or alternatively it may receive information sent to it by some even or periodic sending of data by the application or service being monitoring. Step 2, the Monitor Agent rolls up the data, where the roll up may include aggregating and summing data, and it may also include filtering data out that is not required or within thresholds that don’t need to be reported on. The data may be collected so it may be sent in bulk efficiently rather than parcelled out and causing many interrupts. Step 3, the Monitor Agent may transmit data to the Analytics Engine. The analytics engine may then parse the data and again may perform aggregations, summation, filtering, or other correlation. Step 4, the analytics engine may then evaluate data against a set of configured thresholds that are configured by the policy engine. If a threshold is found to have been exceeded, then the event system may kick in and take action based on the configured policy. Step 5 is executing the configured policy action, which could include notification of some set of individuals or other system by phone, email, pager, text message, event bus, programmed call out, shell script, or other configured mechanism.\n\nIn the illustrated embodiment, governor module 103 utilizes instance placement 627 to make decisions on where to place an instance of a cloud-computing resource. For example, when an instance is built for a cloud-computing service using a builder module, it can be tagged (e.g., using a metamodel) to prevent deployment to certain zones (e.g., security zone) as part of a security policy, cost control policy, performance or availability management policy. Instance placement 627 may cause the governor module 103 to place an instance of a cloud-computing resource based on availability of client-computing resources, or (real-time) performance of particular clouds. Virtual Machine (VM) lifecycle management 624 may be utilized by governor module 103 to determine and enforce expiration of virtual machines Auto-scale 621 maybe utilized by governor module 103 to scale computer workloads being performed on one or more a cloud-computing resources. Auto-scale 621 can add or remove instances of cloud-computing resources to increase or decrease the performance of computer workloads based on monitored resource consumption, a schedule, or a set of rules. Availability & disaster recovery 618 may be utilized when operation of a cloud-computing resource has failed and the failed cloud-computing resource must be recovered according to the constraints, conditions, or policies governed by governor module 103.\n\nFIG. 8 is a flowchart illustrating an example method 700 in accordance with an embodiment of the present invention. Method 700 begins at operation 703 by providing a user a virtual private cloud (VPC) configured to utilize a cloud-computing resource from the plurality of cloud-computing resources to perform a computer workload. At operation 706, method 700 then receives a request to perform the computer workload within the virtual private cloud. For example, in some embodiments, the computer workload may be an application, a server, a platform (e.g., LAMP server), or an infrastructure element (e.g., load-balancing unit). In another example, receiving the request to perform the computer workload comprises: receiving an application to be migrated to cloud-computing environment for execution; and identifying the computer workload as necessary for executing the application. In yet another example, method 700 receives a computing workflow to be performed in the cloud-computing environment; and then identifies a computer workload to perform the computing workflow.\n\nThen, at operation 709, method 700 identifies a cloud-computing resource to perform the computer workload. For example, identifying the cloud-computing resource may be based on a workload score determined by a scoring logic. For instance, the scoring logic may be based on a business attribute of the computer workload (e.g., whether it is mission-critical, required to satisfy a legal obligation, required for an SLA, or the like), a technical attribute of the computer workload (e.g., storage required, bandwidth required, processing speed required, or the like), an operational attribute of the computer workload (time of day for availability, seasonality, or the like), or any combination thereof. In some embodiments, the scoring logic may further be editable or grouped into collections of logic to provide scoring plans for examining multiple types of computer workloads different ways (e.g., a grid computing scoring plan scoring workloads for an application destined to a cloud-computing service hosting grid workloads). In other embodiments, the scoring logic may be editable to allow enterprises to store business, technical, and operational attributes of a computing workload, using enterprise-specific nomenclature or to allow for an enterprise to adjust attributes to a preferred score, consistent with business, technical, or operational metrics. In other embodiments, the scoring algorithm could be configurable, to weight the different attributes of the scoring algorithm based on business, technical, and operational metrics. The scoring algorithms are configurable in multiple ways and the scores are created by a set of rules. The rules may be cloud readiness rules, cloud value rules, or the like: The rule logic may be expressed as\njavascript, java, or the like. The rules make it possible to call any programming language system, configuration management data system, or the like. In embodiments, the information retrieved by the rules can be added to the metamodel for the specified information technology resource. Rules are evaluated according to a plan. A plan is a set of rules the weighting value assigned to each rule. For example, when a rule is a business criticality rule based on a set of metrics, and a plan is a \"business contingency plan\", where the goal is to move infrastructure into a cloud that has disaster recovery and high availability built into it, the a system with the highest business criticality weight, may be moved first. When an item has been evaluated, the weighting values assigned to that item will be added to the metamodel associated with that item. Items could be systems, servers, databases, applications, workloads, and the like. Filters are used to define where items are placed. The filter first identifies the places where an item can be placed and then places the item in the place that is determined to be the best fit for the item. If data assigned to score an item is complete, it will be marked as scored and appear in relevant reports. If data assigned to score an item is incomplete, the items will be identified as requiring remediation. Different data attributes can be tagged as requiring different classes of individuals to complete the required information and preventing other classes of individuals from doing the same. Classes of individuals could be business users, technical users, and the like.\n\nIn embodiments, the present invention may provide for the categorization of workloads into workloads. Each computing workflow can be separated into sets of different workloads, each workload having requirements such as input, storage, processing, output, and the like. Each computing workload may have policy and metadata information stored by the system that includes system information it is, how the computing workload is used, how quickly the computing workload needs to be performed, and the like. Each computing workload is instantiated through a customizable workflow. For example, a computing workload may require approval by a business unit, development team, quality assurance team, and operations team. The workflow in this example would then be instantiated to solicit approval of requirements defined by each workload from each team.\n\nAt operation 712, method 700 provisions the cloud-computing resource from the plurality of cloud-computing resources for the virtual private cloud (VPC). For example, method 700 may provision by locating an unreserved cloud-computing resource within the plurality of cloud-computing resources for the virtual private cloud the unreserved cloud-computing resource. Method 700 deploys the cloud-computing resource within the virtual private cloud at operation 715. Where the cloud-computing resource is a virtual computing resource, the virtual computing resource may be deployed under control of a virtual machine manager. In other embodiments, method 700 may deploy the cloud-computing resource according to a condition for the computer workload, where the condition determines if or when the cloud-computing resource can be deployed within the virtual private cloud to perform the computer workload. For example, the condition may require that the computer workload for backup servers only operate during evening periods. To optimize performance of a computer workload, some embodiments may deploy a pre-determined set of cloud-computing resources to optimize the computer workloads' performance.\n\nOnce the cloud-computing resource is deployed to the virtual private cloud, method 700 uses the cloud-computing resource to perform the computer workload at operation 718. Then, at operation 721, method 700 applies a policy or constraint on the cloud-computing resource. For example, where a policy is associated with a computer workload, method 700 may govern operation of the cloud-computing resource performing the computer workload in accordance with the policy.\n\nFIGS. 9A-9D are screenshots of an example user interface in accordance with some embodiments of the present invention. FIG. 9A depicts a screenshot of a user interface to a planner module, which can plan cloud-computing service comprising one or more cloud-computing resources. In the screenshot shown, a corporate blog application and a logistics application are shown being planned for creation. FIG. 9B depicts a screenshot of a user interface to a builder module, which can build a cloud-computing service comprising one or more cloud-computing resources. The illustrated screenshot shows a stack being built on an Linux base stack. FIG. 9C depicts a screenshot of a user interface to a consumption module, which can be utilized by a user to subscribe to and use a cloud-computing service comprising one or more cloud-computing resources. The screenshot for the consumption module user interface allows a user to subscribe to and use such instances as Linux, Windows® 2003 IIS server, and Flatpress Blog Engine, and more. FIG. 9D depicts a screenshot of a user interface to a manager module, which can be utilized by a user to manage cloud-computing service and its one or more cloud-computing resources. The screenshot shows the user interface of the manager module allowing a user to issue commands to cloud-computing services, such as stopping, running scripts, creating storage volumes, and attaching storage volumes to the cloud-computing services. The interface may be a web page, command line, development tool, and the like, such as eclipse or visual studio, and apps such as iphone/ipad applications. In embodiments, an API may be called that will allow a user to make changes and consume services in a way that is consistent with the company policy. For instance, an API may be implemented as a REST and SOAP interface, which are standard formats for services that may be exposed over different protocols in a standard way.\n\nProject team members may have substantially different functional roles, and as such, each user interface module may be designed to support one or more of the functional roles encountered in the Systems Development Life Cycle (SDLC). The user interface Modules represented in FIGS. 9A-9D may be accessed and used by project team members and presented for the functions those team members may have in the systems development life cycle of the project for which the cloud-computing services are being designed, built, provisioned, and consumed. As well, the interface to each module may be designed to best serve the type of function that will be performed as part of the SDLC phase being addressed. The user interface components of each module may access the Policy Engine in order to represent the controls, access, and assets available to the functionally specific users in order to preserve the integrity, security and compliance of the cloud-computing services each aspect of the SDLC phase.\n\nThe present invention may provide a comprehensive enterprise-grade facility based on federation of IaaS, PaaS, SaaS, and the like, delivered by a plurality of internal and external cloud providers enabling advantages including the ability to intelligently govern, secure, and manage a user's critical applications for cloud environments; automate plan-\nning, building, sharing, and running lifecycle for optimal speed and efficiency, providing policy driven, end-to-end identity management across the plurality of cloud environments; deliver comprehensive cost, performance, and consumption visibility; integrate with a client’s existing IT infrastructure including asset management, authentication and authorization, audit and governance, performance monitoring, and chargeback billing systems; and the like. In other embodiments, the present invention may provide for a layer that allows the input of chargeback billing data to be imported from reporting tools or integrated monitoring systems and the ability to “over recover” or “under recover” charges from the service provider’s specified rates, providing a comprehensive audit trail. For example, if an enterprise is providing its internal users value-added services based on the Amazon EC2 service, the enterprise can add its own costs to the rate charged by Amazon, to recover the costs the enterprise incurs when providing the service to the internal users.\n\nReferring to FIG. 10, an alternate module structure is depicted for the platform 20 for providing capabilities to specific roles across the lifecycle, including a planner module 1002 (which may have any of the capabilities described for the planner module 23), a designer module 1004 (which may have any of the capabilities of the design module 29), a centerpoint module 1008, a manager module 1010 (which may have any of the capabilities of the manager module 26), and an access module 1012, which may collectively provide the platform with management, security, policy, governance, and the like functionality as described herein. The platform 20, as in the example depicted in FIG. 1 and detailed herein, is able to provide virtual private cloud facilities to users through the cloud provider environment, including external private clouds 1014 (e.g., external companies, such as Savvis, with dedicated connectivity and instances), internal private clouds 1018 (e.g., current data centers that support virtualization and cloud), secure public clouds 1020 (e.g., multi-tenant architectures, such as Amazon), PaaS providers 1022, SaaS providers 1024, and the like. The functions depicted in FIG. 1 of the Cloud-Computing Platform 20 map directly to the modules depicted in FIG. 10, Platform 20 as follows; Planner Module 23 maps directly to the Planner Module 1002, the Builder Module 29 maps directly to the Designer Module 1004, the Consumption Module 32 maps directly to the CenterPoint Module 1008, and the Manager Module 26 maps directly to the Manager Module 1010. The Repository Module 30 of FIG. 1 is encompassed in the platform database and functions provided and depicted as Governance, Policy, Security and Management for the Platform 20. The Access Module 1012 provides a single sign-on function for the platform 20 allowing connectivity to enterprise identity systems such as LDAP/AD, which is shown in FIG. 5 and maps to the Identity Module 29. The planner module 1002 may help analysts and architects streamline application migration activities by analyzing and scoring application workloads to evaluate their suitability, generate recommendations right-sizing and right-placement across multiple internal as well as external service provider options. The planner module 1002 may also allow analysts and architects the ability to construct new rules and rule-sets for evaluating new and different types of application workloads in evaluating cloud readiness, cloud value, and right placement recommendations. The designer module 1004 may provide technical users with a graphical workbench to rapidly assemble policy-compliant stacks, workloads, and applications for any number of deployment environments. It may include a library of pre-built, reusable assets with the ability to create and publish new ones. The centerpoint module may facilitate the sharing and collaboration of cloud assets with fine-grain access controls, search capabilities, automated notifications, rating and commenting of assets, and access to detailed consumption reports. The manager module 1010 may provide a unified interface to streamline deployment and runtime management for any number of cloud providers, including monitoring of running instances and detailed performance and costing information. The access manager 1012 may deliver federated identity management to the full range of highly dynamic services managed (e.g., including IaaS, PaaS, and SaaS providers) along with the platform 20. It may also integrate with and support a plurality of protocols, such as LDAP, Active Directory, X.500, and the like. In each case the modules represented may reside on a common Policy Engine that ensures the integrity and security of the system by enforcing policy and access rights for the users accessing each module are only accessing those assets and functions that are allowed for their functional role.\n\nThe platform 20 may exist in an IT ecosystem and utilize a plurality of both cloud-based and dedicated resources to integrate with the platform, where these integration points may take place both within an enterprise’s existing IT infrastructure, and also extend out to a plurality of external providers and services, such as in applying to both pre-production and production cloud environments. FIG. 11 provides an example illustration of the IT ecosystem as a plurality of these both dedicated and cloud-based resources, including security 1102 (e.g., proxy integration, host firewalls, hypervisor-based firewalls, host intrusion detection, external key store, VLAN management, VPN, file system encryption), IaaS 1104, external clouds 1108 (e.g., GoGrid, Amazon, Terremark, Savvis, vCloud Director based Cloud offerings (Dell and others), Joyant, vCloud Express offerings), storage 1110 (e.g., NFS, VMFS, SAN, Amazon S3, EMC, Oracle, Netapp), internal clouds 1112 (e.g., vSphere, Cloud.com, Equatypus, OpenStack, HyperV, Xen, KVM), PaaS 1114 (e.g., Hadoop, Azure, EnterPaaS, VMware CloudFoundry, IBM WebSphere, Oracle WebLogic), orchestration 1118 (e.g., Autoscaling, Scripting framework, File management), SaaS 1120 (e.g., Salesforce.com, Intuit, Google Apps), desktop as-a-service 1122 (e.g., Citrix, VMware, Cicero, Framewawk), accounting and chargeback 1124 (e.g., Ariba, SAP), continuous integration 1128 (e.g., Collabnet, Apache Maven, Subversion, Jenkins CI), disaster recovery 1130 (e.g., Double Take), network services 1132 (e.g., DNS, DHCP, Load Balancer, NTP), governance 1134 (e.g., Axway, SOA Software), performance monitoring 1138 (e.g., Manage, Collectd), identity management 1140 (e.g., Oracle OAM, Netegrity, LDAP Kerberos SAML, RSA ClearTrust, Active Directory), and the like.\n\nReferring to FIG. 12, the platform 20 may deliver unified governance for IaaS, PaaS, and DaaS workloads across a federation of internal and external cloud providers 1202, 1204, 1208, to leverage scheduling and placement policies to optimize the placement and type of workloads that are being run on a temporal or scheduled basis. As an example, during the day, scheduling policies may devote much of the cloud compute capacity to running virtualized desktops, however, as the evening approaches and workers go home, the demand for DaaS drops, and the cloud compute capacity can be utilized for compute intensive applications such as financial trade simulation models running on grid-compute nodes. This policy approach also allows cloud-compute services to be shifted to lower cost Cloud Provider environments. As such, the inherent policies provided by the plat-\nform lower costs by maximizing the utility of the cloud infrastructure while also having the same effect of lowering costs by aligning workload placement to provider environments best fit to run those types of workloads.\n\nIn embodiments, policy-driven governance may be integral to the platform and to the end-to-end lifecycle to create and enforce policies in a closed-loop governance lifecycle, such as extensible policy framework to support unique, customizable approval workflow, integration with corporate audit and governance systems, establishing a foundation for audits and policy reviews, and the like. Referring again to FIG. 10, the planner module 1002 may contribute to the creation of design-time policies, such as access rights, right-placement parameters, regulatory restrictions, and the like. The designer module 1004 may contribute to the creation of run-time policies, such as auto-scaling parameters, maximum instances allowed, and the like. The centerpoint module 1006 may enforce access policies, ensuring that the right users are accessing the right assets and deploying those assets in the right place, and the like. The manager module 1010 may enforce run and design-time policies, such as allowing cloud-compute services to scale up or down in response to load or other conditions in the environment as well as prevent users from consuming arbitrary amounts of compute resources, and the like. The access module 1012 may enforce access policies across internal and external service providers, and the like. In this way, policy creation is an integrated process across the platform.\n\nIn embodiments, the present invention may provide many advantages, including a unified interface to deploy and monitor workloads across internal and external service providers; rapid creation of new workloads and re-architect existing ones for cloud portability and on-demand provisioning; automated right-sizing, right-placement, and user access decisions via enforceable policies; deployable and dynamically configurable complex application topologies in real-time; meter usage with integrated chargeback and billing; real-time monitoring and support for auto-scaling and bursting across multiple clouds; federated identity management across internal and external providers; pre-built library of re-useable stacks to accelerate assembly and deployment; incorporated end-to-end security that spans network, access rights, instances, and data; complete visibility and transparency via role-based reports, policy reviews, and audit trails; creation and enforcement of policies in a closed-loop governance and management lifecycle; score and prioritization of workloads for migration; consolidated monitoring, reporting and metering including integrated chargeback/billing; platform deployment flexibility to locate securely on premises or as a SaaS offering; and the like.\n\nAutomated governance through the present invention may enable new capacity optimization strategies to maximize the utilization of hardware and server resources through the dynamic placement of different sized workloads, where the platform may manage placement of workloads from large (e.g. production applications, load test environments) to small (e.g. virtual desktops), perform monitoring and management application auto-scaling, rollers with external cloud providers when internal capacity limits are reached, and the like. Use of the platform across a plurality of cloud workloads, may allow the user to create new capacity optimization strategies to make the most from a user’s internal resources, such as though dynamic placement of different sized workloads, and combining these workloads to achieve high capacity and/or utilization of a given computing facility. To enable this, the platform may perform application monitoring, workload placement, workload scheduling as well as workload and application auto-scaling, and the like, as appropriate.\n\nIn embodiments, the present invention may provide for a self-service enterprise application store, which provides access to a global, cross-platform, software distribution network for multiple service offerings, accessible through any web browser such as Microsoft Internet Explorer, Mozilla Firefox, Google Chrome, and the like. In embodiments such an enterprise application store may be used to drive virtual desktop installations, provision enterprise server systems, and integrate with SaaS offerings. In embodiments such an enterprise application store may provide a full range of services to manage and monitor the provisioning of services. The services could be a wide range of services required by enterprises, such as software publishing and ordering, order approval, license management, chargeback and invoicing, integration with a global marketplace, and the like. The service offerings could be infrastructure as a service (IaaS), platform as a service (PaaS), and software as a service (SaaS) offerings, and the like. In further embodiments, the service offerings could be internal services, open source services, third party services, and the like. In further embodiments, the present invention may provide for a single sign-on capability for each of the service offerings.\n\nThe application store software publishing capability can include tools to package and publish software and services to the application store, such as to allow a customer of services from the application store to develop its own software and publish its own service, which in turn can be made available through the application store. For example, a service builder could obtain from the enterprise application store a set of services that store data such as various sources. The service builder can then build its own service by adding a processing service that processes the inputs into outputs that are stored in the data storage and made available for other users who wish to have those outputs, such as for their own services. The new service can be stored in the enterprise application store for further use by others. A user of the enterprise application store may organize software services into manageable “catalogs” to control user access and experience, apply rich security, usage, and billing policies to entire catalogs, catalogs of catalogs, individual offerings, configure workflows for publishing approvals, and the like.\n\nThe application store software ordering capability can include an intuitive interface for browsing and purchasing published software and services, allow a user to purchase software and services for itself or on behalf of an entire group of users, schedule deployments upon purchase or for a date in the future, and the like. In other embodiments, the software ordering capability can include a customizable user interface, which allows a user to build browsing and ordering interface widgets customized to the needs of the user and then make those widgets available to the user’s users through the application store.\n\nThe software application store order approval capability can include an integrated purchase approval system that follows a flexible workflow that is consistent with industry standards and best practices, a pluggable service model to allow for transparent integration with third-party approval systems, and the like. In other embodiments the order approval capability includes a highly customizable workflow that can be built from individual approval systems that\ncan be chained-together in various and selectable sequences. These various and selectable sequences can be varied by catalog, catalog item, user, user group, and the like.\n\nIn embodiments, the ordering and approval capabilities may be filtered or otherwise limited by the user who is placing the order and/or the application on whose behalf the order is being placed. Results made available to a user and/or an application may be pre-filtered to only show those services that are available to that user and/or application. The user can be categorized by its role in the organization, or the like. The application can be categorized by its role, function, assigned policies, and the like.\n\nThe license management capability can include the creation of detailed licensing polices for individual software modules and services, a component model to allow for integration with a wide range of vendor licensing servers, runtime license checking when used with virtual machine instances managed by the present invention, and the like.\n\nThe chargeback and invoicing capability can include an integrated change management service with a configurable workflow, an adapter model allowing for integration with existing financial and asset management systems, flexible pricing policies to allow for the establishment of one-time charges or variable, usage based models, detailed organization modeling to allow for the distribution of cost across multiple cost centers, a flexible API that allows for the customization of the billing workflow, and the like. For example, invoices could be posted directly to the enterprise’s enterprise resource planning (ERP) or payables system. In other embodiments, the present invention provides for the ability to report chargeback and invoicing information to both the user of the service and the provider of the service from the software application store.\n\nThe capability to be integrated with a global marketplace can include publish and subscribe access to an open market of verified software, an integrated and stringent approval process of all submissions, access to a free catalog of packaged and open-source solutions, the ability of a user to package and upload its custom solutions for exposure to a global market, the ability of a user to offer its software free or through a licensing/pricing model with automated chargeback, defined by the user, and the like.\n\nIn embodiments of the present invention, the software application store supports the recursive publishing of applications. The recursive publishing could include multiple iterations of an application published by multiple users, groups of users, enterprises, and the like. For example, a first department of a first enterprise could publish a first IaaS application back into the software application store, a second department of the first enterprise could then publish a PaaS application on top of the IaaS application published by the first department, and a third department of the first enterprise could purchase the PaaS built on top of the IaaS application and the license fees paid by the third department would be split between the first and second departments.\n\nIn embodiments of the present invention, the data may be associated with the content available in the software application store and SKU, policy, SKU-Policy, catalog, and the like. An SKU is the primary entity describing content available through the software application store and is a pure virtual entity describing a potentially addressable software component or interaction. An interaction can be a module, service, or the like. An SKU can be defined as a software module or a service binding. A software model represents and offering comprised of one or more physical software components, which can include source code, binaries, and the like, and the software module encapsulates the information needed to resolve binaries to locations on the shared filesystem, resolve binary dependencies, locate and provision associated software packages, and the like. A service binding models a software-as-a-service (SaaS) type offering and encapsulates the information needed to configure user access to services, authenticate, bind to services, and the like. A policy will be applied as defined by standard policy types, resolved, and applied by modules as described elsewhere in this disclosure. In other embodiments, additional policy types and definitions, with possible extensions to existing models, may be added to support the software application store.\n\nAn SKU-Policy is the collection of policies associated with a given SKU and is an extensible set of required or optional policies, which may be conditionally applied. A catalog is a collection of SKU’s, filtered through access control, which can be applied at any level and made available to a group of users. In further embodiments access control can be used to introduce further groupings below the root level. A given catalog instance is a rule-based expression of the root catalog. The root catalog is defined as the base set of SKU data available to all subscribers. All SKU’s published in the root catalog are “inherited” by all derived catalogs. For example, the basic catalog hierarchy can be root catalog→customer catalog→user catalog.\n\nFIG. 13 depicts an embodiment of a software application store and marketplace interaction structure, such as with software application store services, including policy management, object models, process handlers, repository providers, filesystem services and workflow services, interfacing with marketplace services, such as with software application store workflow connectors, a shared filesystem, a software application store repository, and the like. The components could be a marketplace, shared filesystem, filesystem client, server components, repository, user interface, and the like. The marketplace is the central “public” repository that hosts the components listed in the root catalog, consists of a cluster of servers hosting a portion of the shared filesystem and a subset of the software application workflow components to manage publishing, approvals, and browsing. The marketplace may have its own basic user interface consisting of a few simple web pages, which provide access to the functionality of the software application interface. The shared filesystem may be a clustered, parallel filesystem housing all the physical components needed by the software application store and its offerings. The filesystem may be self-contained and maybe used outside of the software application store or the system of the present invention. For example, marketplace catalog items can be hosted on the shared filesystem. The software application store may offer service components that simplify filesystem administration tasks and serve to isolate other components from the physical filesystem implementation. The filesystem client may be a client that accesses the software application store shared filesystem namespace using local filesystem semantics. For example, the namespace root may appear to the user as a local mount point or network mapped drive. In other embodiments, a number of client-side components may be installed to provide access to the software application store shared filesystem through the filesystem client. The present invention requires at least one client package for each target operating system and/or distribution. The filesystem client components are distributed through standard packages of the present invention that contain the scripts and attachment necessary to establish connectivity to the software application store shared filesystem through the filesystem client.\nThe server components may be the core applications of the software application store and include the base object model, workflow processing components, catalog and metamodel access providers, unique policy definitions, and the like. The repository may be the collection of data structures hosting the software application store metamodel, configuration, and catalog data, and the like; and are internal to the software application store. The user interface may be the collection of interface elements used to access software application store functionality and is implemented as a completely separate application that integrates with the main user interface of the present invention, describe elsewhere in this disclosure. In further embodiments, the software application store may make available shareable widgets that are an extension of the software application store user interface.\n\nIn other further embodiments, the software application store includes the capabilities to display lists of applications, application ratings, application reviews, other social features, and the like.\n\nThe term tool can be used to refer to any apparatus configured to perform a recited function. For example, tools can include a collection of one or more modules and can also be comprised of hardware, software or a combination thereof. Thus, for example, a tool can be a collection of one or more software modules, hardware modules, software/hardware modules or any combination or permutation thereof. As another example, a tool can be a computing device or other appliance on which software runs or in which hardware is implemented.\n\nAs used herein, the term module might describe a given unit of functionality that can be performed in accordance with one or more embodiments of the present invention. As used herein, a module might be implemented utilizing any form of hardware, software, or a combination thereof. For example, one or more processors, controllers, ASICs, PLAs, PALs, CPLDs, FPGAs, logical components, software routines or other mechanisms might be implemented to make up a module. In implementation, the various modules described herein might be implemented as discrete modules or the functions and features described can be shared in part or in total among one or more modules. In other words, as would be apparent to one of ordinary skill in the art after reading this description, the various features and functionality described herein may be implemented in any given application and can be implemented in one or more separate or shared modules in various combinations and permutations. Even though various features or elements of functionality may be individually described or claimed as separate modules, one of ordinary skill in the art will understand that these features and functionality can be shared among one or more common software and hardware elements, and such description shall not require or imply that separate hardware or software components are used to implement such features or functionality.\n\nWhere components or modules of the invention are implemented in whole or in part using software, in one embodiment, these software elements can be implemented to operate with a computing or processing module capable of carrying out the functionality described with respect thereto. One such example computing module is shown in FIG. 10. Various embodiments are described in terms of this example computing module 900. After reading this description, it will become apparent to a person skilled in the relevant art how to implement the invention using other computing modules or architectures.\n\nReferring now to FIG. 10, computing module 900 may represent, for example, computing or processing capabilities found within desktop, laptop and notebook computers; hand-held computing devices (PDAs, smart phones, cell phones, palmtops, etc.); mainframes, supercomputers, workstations or servers; or any other type of special-purpose or general-purpose computing devices as may be desirable or appropriate for a given application or environment. Computing module 900 might also represent computing capabilities embedded within or otherwise available to a given device. For example, a computing module might be found in other electronic devices such as, for example, digital cameras, navigation systems, cellular telephones, portable computing devices, modems, routers, WAPs, terminals and other electronic devices that might include some form of processing capability.\n\nComputing module 900 might include, for example, one or more processors, controllers, control modules, or other processing devices, such as a processor 904. Processor 904 might be implemented using a general-purpose or special-purpose processing engine such as, for example, a microprocessor, controller, or other control logic. In the illustrated example, processor 904 is connected to a bus 902, although any communication medium can be used to facilitate interaction with other components of computing module 900 or to communicate externally.\n\nComputing module 900 might also include one or more memory modules, simply referred to herein as main memory 908. For example, preferably random access memory (RAM) or other dynamic memory, might be used for storing information and instructions to be executed by processor 904. Main memory 908 might also be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor 904. Computing module 900 might likewise include a read only memory (\"ROM\") or other static storage device coupled to bus 902 for storing static information and instructions for processor 904.\n\nThe computing module 900 might also include one or more various forms of information storage mechanisms 910, which might include, for example, a media drive 912 and a storage unit interface 920. The media drive 912 might include a drive or other mechanism to support fixed or removable storage media 914. For example, a hard disk drive, a floppy disk drive, a magnetic tape drive, an optical disk drive, a CD or DVD drive (R or RW), or other removable or fixed media drive might be provided. Accordingly, storage media 914 might include, for example, a hard disk, a floppy disk, magnetic tape, cartridge, optical disk, a CD or DVD, or other fixed or removable medium that is read by, written to or access by media drive 912. As these examples illustrate, the storage media 914 can include a computer usable storage medium having stored therein computer software or data.\n\nIn alternative embodiments, information storage mechanism 910 might include other similar instrumentalities for allowing computer programs or other instructions or data to be loaded into computing module 900. Such instrumentalities might include, for example, a fixed or removable storage unit 922 and an interface 920. Examples of such storage units 922 and interfaces 920 can include a program cartridge and cartridge interface, a removable memory (for example, a flash memory or other removable memory module) and memory slot, a PCMCIA slot and card, and other fixed or removable storage units 922 and interfaces 920 that allow software and data to be transferred from the storage unit 922 to computing module 900.\n\nComputing module 900 might also include a communications interface 924. Communications interface 924 might\nbe used to allow software and data to be transferred between computing module 900 and external devices. Examples of communications interface 924 might include a modem or softmodem, a network interface (such as an Ethernet, network interface card, WiMedia, IEEE 802.XX or other interface), a communications port (such as for example, a USB port, IRport, RS232 port, Bluetooth® interface, or other port), or other communications interface. Software and data transferred via communications interface 924 might typically be carried on signals, which can be electronic, electromagnetic (which includes optical) or other signals capable of being exchanged by a given communications interface 924. These signals might be provided to communications interface 924 via a channel 928. This channel 928 might carry signals and be implemented using a wired or wireless communication medium. Some examples of a channel might include a phone line, a cellular link, an RF link, an optical link, a network interface, a local or wide area network, and other wired or wireless communications channels.\n\nIn this document, the terms “computer program medium” and “computer usable medium” are used to generally refer to media such as, for example, memory 908, storage unit 920, media 914, and channel 928. These and other various forms of computer program media or computer usable media may be involved in carrying one or more sequences of one or more instructions to a processing device for execution. Such instructions embodied on the medium, are generally referred to as “computer program code” or a “computer program product” (which maybe grouped in the form of computer programs or other groupings). When executed, such instructions might enable the computing module 900 to perform features or functions of the present invention as discussed herein.\n\nAs noted throughout, organizations are increasingly leveraging hybrid cloud environments that span multiple internal private clouds, external hosted clouds, public infrastructure-as-a-service (IaaS), and/or platform-as-a-service (PaaS). The ability to deploy complex multi-tier workloads into these heterogeneous multi-vendor environments may require a meta-scheduler of the above-discussed metamodel that can place workloads to achieve the best price, performance, and service levels, while providing governance and controls around security and compliance. As such, the “meta-scheduler” may comprise an extension to the policy and governance models discussed herein.\n\nIn the known art, users may consume cloud-based IT resources using a self-service portal (also referred to as a “service catalog”). Typically, self-service portal resources are categorized as the aforementioned infrastructure-as-a-service (IaaS), platform-as-a-service (PaaS), or software-as-a-service (SaaS). The primary difference between IaaS, PaaS, and SaaS is the “completeness” of the resource. IaaS delivers low-level operating system instances. PaaS delivers a larger middleware environment, suitable for deploying application code. SaaS delivers high-level, full-featured, ready-to-use applications.\n\nHigher-level offerings can be built on lower-level offerings. For instance, one can build a Paas offering by starting with IaaS resources and then adding and configuring middleware software. Similarly, SaaS applications can be built on a Paas offering.\n\nHowever, self-service portals typically operate in a very restricted fashion, with very few people who create offerings and a large number of people that consume offerings. This is fine for simplistic needs, but artificially restricts innovation.\n\nConsequently, and now with reference to FIGS. 15-17, embodiments of the present invention provide a self-service portal that allows the layering of offerings by a large majority of users. Thus, through the use of embodiments of the instant invention, a user may find and consume a low-level IaaS offering, and may use it to build a Paas offering by adding and configuring middleware software components. That Paas offering may then be “republished” back into the self-service portal for consumption by others. Further, a Paas offering (including a new Paas offering based on the IaaS offering, as just described) may be consumed, and then may be used to create a SaaS offering, which may then be republished back into the portal.\n\nOftentimes, the consumption of low-level services and republishing of higher-level services built thereupon will occur within a single enterprise. For instance, the IT department might create a standard Paas offering for application developers using IaaS resources.\n\nHowever, the consumption and republishing may occur between different organizations using a global self-service portal. For instance, Company A may offer IaaS in the service catalog associated with the self service portal. Company B may consume the IaaS and may use it to create a Paas offering, which may then be offered back to the service catalog. Company C may then consume Company B’s Paas and may use it to create a SaaS offering. Company D may then consume the SaaS. Of note, intermediate levels may be skipped in such embodiments. That is, IaaS may be used directly to create SaaS, for instance, without needing a Paas intermediary.\n\nOf course, those skilled in the pertinent arts will appreciate in light of the discussion herein, that money (real or internal enterprise budgets) may flow between the various publishers. For instance, consumption of an IaaS resource may “cost” a given amount. A Paas creator may consider those costs as “cost of goods sold” and price that creator’s Paas offering to cover those costs. A SaaS creator might then do the same with Paas or IaaS costs, as appropriate. When services are consumed at any level, the self-service portal would correctly handle the payment of “money” to all the parties involved.\n\nAs such, embodiments of the present invention provide a self-service portal with the ability to “republish” at different levels. Further, provided is the capability to chain the republishing steps together (IaaS→Paas→SaaS), such as with multiple republishing steps. The subject self-service portal may allow for consumption of different levels (IaaS, Paas, and SaaS), and is operable between multiple entities (i.e., different departments, different corporate entities) to allow for the referenced republishing. Moreover, the self-service portal of the invention allows for the handling of money flow between all the parties in a single or multi-party chain of publishers.\n\nWhile various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not of limitation. Likewise, the various diagrams may depict an example architectural or other configuration for the invention, which is done to aid in understanding the features and functionality that can be included in the invention. The invention is not restricted to the illustrated example architectures or configurations, but the desired features can be implemented using a variety of alternative architectures and configurations. Indeed, it will be apparent to one of skill in the art how alternative functional, logical or physical partitioning and configurations can be implemented to implement the desired features of the present invention. Also, a multitude of\ndifferent constituent module names other than those depicted herein can be applied to the various partitions. Additionally, with regard to flow diagrams, operational descriptions and method claims, the order in which the steps are presented herein shall not mandate that various embodiments be implemented to perform the recited functionality in the same order unless the context dictates otherwise.\n\nAlthough the invention is described above in terms of various exemplary embodiments and implementations, it should be understood that the various features, aspects and functionality described in one or more of the individual embodiments are not limited in their applicability to the particular embodiment with which they are described, but instead can be applied, alone or in various combinations, to one or more of the other embodiments of the invention, whether or not such embodiments are described and whether or not components are predicted as being a part of a described embodiment. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments.\n\nTerms and phrases used in this document, and variations thereof, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing: the term “including” should be read as meaning “including, without limitation” or the like; the term “example” is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof; the terms “a” or “an” should be read as meaning at least one, one or more, or the like; and adjectives such as “conventional,” “traditional,” “normal,” “standard,” “known” and terms of similar meaning should not be construed as limiting the item described to a given time period or to an item available as of a given time, but instead should be read to encompass conventional, traditional, normal, or standard technologies that may be available or known now or at any time in the future. Likewise, where this document refers to technologies that would be apparent or known to one of ordinary skill in the art, such technologies encompass those apparent or known to the skilled artisan now or at any time in the future.\n\nThe presence of broadening words and phrases such as “one or more,” “at least,” “but not limited to” or other like phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent. The use of the term “module” does not imply that the components or functionality described or claimed as part of the module are all configured in a common package. Indeed, any or all of the various components of a module, whether control logic or other components, can be combined in a single package or separately maintained and can further be distributed in multiple groupings or packages or across multiple locations.\n\nAdditionally, the various embodiments set forth herein are described in terms of exemplary block diagrams, flow charts and other illustrations. As will become apparent to one of ordinary skill in the art after reading this document, the illustrated embodiments and their various alternatives can be implemented without confinement to the illustrated examples. For example, block diagrams and their accompanying description should not be construed as mandating a particular architecture or configuration.\n\nWhile the invention has been described in connection with certain preferred embodiments, other embodiments would be understood by one of ordinary skill in the art and are encompassed herein.\n\nThe methods and systems described herein maybe deployed in part or in whole through a machine that executes computer software, program codes, and/or instructions on a processor. The present invention may be implemented as a method on the machine, as a system or apparatus as part of or in relation to the machine, or as a computer program product embodied in a computer readable medium executing on one or more of the machines. The processor may be part of a server, client, network infrastructure, mobile computing platform, stationary computing platform, or other computing platform. A processor may be any kind of computational or processing device capable of executing program instructions, codes, binary instructions and the like. The processor may be or include a signal processor, digital processor, embedded processor, microprocessor or any variant such as a co-processor (math co-processor, graphic co-processor, communication co-processor and the like) and the like that may directly or indirectly facilitate execution of program code or program instructions stored thereon. In addition, the processor may enable execution of multiple programs, threads, and codes. The threads may be executed simultaneously to enhance the performance of the processor and to facilitate simultaneous operations of the application. By way of implementation, methods, program codes, program instructions and the like described herein may be implemented in one or more thread. The thread may spawn other threads that may have assigned priorities associated with them; the processor may execute these threads based on priority or any other order based on instructions provided in the program code. The processor may include memory that stores methods, codes, instructions and programs as described herein and elsewhere. The processor may access a storage medium through an interface that may store methods, codes, and instructions as described herein and elsewhere. The storage medium associated with the processor for storing methods, programs, codes, program instructions or other type of instructions capable of being executed by the computing or processing device may include but may not be limited to one or more of a CD-ROM, DVD, memory, hard disk, flash drive, RAM, ROM, cache and the like.\n\nA processor may include one or more cores that may enhance speed and performance of a multiprocessor. In embodiments, the process may be a dual core processor, quad core processors, other chip-level multiprocessor and the like that combine two or more independent cores (called a die).\n\nThe methods and systems described herein may be deployed in part or in whole through a machine that executes computer software on a server, client, firewall, gateway, hub, router, or other such computer and/or networking hardware. The software program may be associated with a server that may include a file server, print server, domain server, Internet server, intranet server and other variants such as secondary server, host server, distributed server and the like. The server may include one or more of memories, processors, computer readable media, storage media, ports (physical and virtual), communication devices, and interfaces capable of accessing other servers, clients, machines, and devices through a wired or a wireless medium, and the like. The methods, programs or codes as described herein and elsewhere may be executed by the server. In addition, other devices required for execution of methods as described in this application may be considered as a part of the infrastructure associated with the server.\n\nThe server may provide an interface to other devices including, without limitation, clients, other servers, printers, database servers, print servers, file servers, communication\nservers, distributed servers and the like. Additionally, this coupling and/or connection may facilitate remote execution of program across the network. The networking of some or all of these devices may facilitate parallel processing of a program or method at one or more location without deviating from the scope of the invention. In addition, any of the devices attached to the server through an interface may include at least one storage medium capable of storing methods, programs, code and/or instructions. A central repository may provide program instructions to be executed on different devices. In this implementation, the remote repository may act as a storage medium for program code, instructions, and programs.\n\nThe software program may be associated with a client that may include a file client, print client, domain client, internet client, intranet client and other variants such as secondary client, host client, distributed client and the like. The client may include one or more of memories, processors, computer readable media, storage media, ports (physical and virtual), communication devices, and interfaces capable of accessing other clients, servers, machines, and devices through a wired or a wireless medium, and the like. The methods, programs or codes described herein and elsewhere may be executed by the client. In addition, other devices required for execution of methods as described in this application may be considered as a part of the infrastructure associated with the client.\n\nThe client may provide an interface to other devices including, without limitation, servers, other clients, printers, database servers, print servers, file servers, communication servers, distributed servers and the like. Additionally, this coupling and/or connection may facilitate remote execution of program across the network. The networking of some or all of these devices may facilitate parallel processing of a program or method at one or more location without deviating from the scope of the invention. In addition, any of the devices attached to the client through an interface may include at least one storage medium capable of storing methods, programs, applications, code and/or instructions. A central repository may provide program instructions to be executed on different devices. In this implementation, the remote repository may act as a storage medium for program code, instructions, and programs.\n\nThe methods and systems described herein may be deployed in part or in whole through network infrastructures. The network infrastructure may include elements such as computing devices, servers, routers, hubs, firewalls, clients, personal computers, communication devices, routing devices and other active and passive devices, modules and/or components as known in the art. The computing and/or non-computing device(s) associated with the network infrastructure may include; apart from other components, a storage medium such as flash memory, buffer, stack, RAM, ROM and the like. The processes, methods, program codes, instructions described herein and elsewhere may be executed by one or more of the network infrastructural elements.\n\nThe methods, program codes, and instructions described herein and elsewhere may be implemented on a cellular network having multiple cells. The cellular network may either be frequency division multiple access (FDMA) network or code division multiple access (CDMA) network. The cellular network may include mobile devices, cell sites, base stations, repeaters, antennas, towers, and the like. The cell network may be a GSM, GPRS, 3G, EVDO, mesh, or other networks types.\n\nThe methods, programs codes, and instructions described herein and elsewhere may be implemented on or through mobile devices. The mobile devices may include navigation devices, cell phones, mobile phones, mobile personal digital assistants, laptops, palmtops, netbooks, pagers, electronic books readers, music players and the like. These devices may include, apart from other components, a storage medium such as a flash memory, buffer, RAM, ROM and one or more computing devices. The computing devices associated with mobile devices may be enabled to execute program codes, methods, and instructions stored thereon. Alternatively, the mobile devices may be configured to execute instructions in collaboration with other devices. The mobile devices may communicate with base stations interfaced with servers and configured to execute program codes. The mobile devices may communicate on a peer to peer network, mesh network, or other communications network. The program code may be stored on the storage medium associated with the server and executed by a computing device embedded within the server. The base station may include a computing device and a storage medium. The storage device may store program codes and instructions executed by the computing devices associated with the base station.\n\nThe computer software, program codes, and/or instructions may be stored and/or accessed on machine readable media that may include: computer components, devices, and recording media that retain digital data used for computing for some interval of time; semiconductor storage known as random access memory (RAM); mass storage typically for more permanent storage, such as optical discs, forms of magnetic storage like hard disks, tapes, drums, cards and other types; processor registers, cache memory, volatile memory, non-volatile memory; optical storage such as CD, DVD; removable media such as flash memory (e.g. USB sticks or keys), floppy disks, magnetic tape, paper tape, punch cards, standalone RAM disks, Zip drives, removable mass storage, off-line, and the like; other computer memory such as dynamic memory, static memory, read/write storage, non-volatile storage, read only, random access, sequential access, location addressable, file addressable, content addressable, network attached storage, storage area network, bar codes, magnetic ink, and the like.\n\nThe methods and systems described herein may transform physical and/or intangible items from one state to another. The methods and systems described herein may also transform data representing physical and/or intangible items from one state to another.\n\nThe elements described and depicted herein, including in flow charts and block diagrams throughout the figures, imply logical boundaries between the elements. However, according to software or hardware engineering practices, the depicted elements and the functions thereof may be implemented on machines through computer executable media having a processor capable of executing program instructions stored thereon as a monolithic software structure, as standalone software modules, or as modules that employ external routines, code, services, and so forth, or any combination of these, and all such implementations may be within the scope of the present disclosure. Examples of such machines may include, but may not be limited to, personal digital assistants, laptops, personal computers, mobile phones, other handheld computing devices, medical equipment, wired or wireless communication devices, transducers, chips, calculators, satellites, tablet PCs, electronic books, gadgets, electronic devices, devices having artificial intelligence, computing devices, networking equipments,\nservers, routers and the like. Furthermore, the elements depicted in the flow chart and block diagrams or any other logical component may be implemented on a machine capable of executing program instructions. Thus, while the foregoing drawings and descriptions set forth functional aspects of the disclosed systems, no particular arrangement of software for implementing these functional aspects should be inferred from these descriptions unless explicitly stated or otherwise clear from the context. Similarly, it will be appreciated that the various steps identified and described above may be varied, and that the order of steps may be adapted to particular applications of the techniques disclosed herein. All such variations and modifications are intended to fall within the scope of this disclosure. As such, the depiction and/or description of an order for various steps should not be understood to require a particular order of execution for those steps, unless required by a particular application, or explicitly stated or otherwise clear from the context.\n\nThe methods and/or processes described above, and steps thereof, maybe realized in hardware, software or any combination of hardware and software suitable for a particular application. The hardware may include a general-purpose computer and/or dedicated computing device or specific computing device or particular aspect or component of a specific computing device. The processes may be realized in one or more microprocessors, microcontrollers, embedded microcontrollers, programmable digital signal processors or other programmable device, along with internal and/or external memory. The processes may also, or instead, be embodied in an application specific integrated circuit, a programmable gate array, programmable array logic, or any other device or combination of devices that may be configured to process electronic signals. It will further be appreciated that one or more of the processes may be realized as a computer executable code capable of being executed on a machine-readable medium.\n\nThe computer executable code may be created using a structured programming language such as C, an object oriented programming language such as C++, or any other high-level or low-level programming language (including assembly languages, hardware description languages, and database programming languages and technologies) that may be stored, compiled or interpreted to run on one of the above devices, as well as heterogeneous combinations of processors, processor architectures, or combinations of different hardware and software, or any other machine capable of executing program instructions.\n\nThus, in one aspect, each method described above and combinations thereof may be embodied in computer executable code that, when executing on one or more computing devices, performs the steps thereof. In another aspect, the methods may be embodied in systems that perform the steps thereof, and may be distributed across devices in a number of ways, or all of the functionality may be integrated into a dedicated, standalone device or other hardware. In another aspect, the means for performing the steps associated with the processes described above may include any of the hardware and/or software described above. All such permutations and combinations are intended to fall within the scope of the present disclosure.\n\nWhile the invention has been disclosed in connection with the preferred embodiments shown and described in detail, various modifications and improvements thereon will become readily apparent to those skilled in the art. Accordingly, the spirit and scope of the present invention is not to be limited by the foregoing examples, but is to be understood in the broadest sense allowable by law.\n\nWhat is claimed is:\n\n1. A method comprising:\n receiving, by a computing system, low-level resources for delivering one or more operating system instances, wherein at least first entities publish the low-level resources to a catalog presented at an electronic storefront, and wherein the low-level resources comprise one or more infrastructure-as-a-service (IaaS) offerings provided via a network infrastructure;\n providing, by the computing system, access from the catalog at the electronic storefront to the low-level resources for consumption by at least second entities, the at least second entities being different from the at least first entities;\n constructing, by the computing system, mid-level resources from the low-level resources, wherein the mid-level resources are constructed based, at least in part, on one or more middle-ware components being added to the low-level resources by the at least second entities and being configured by the at least second entities, wherein the mid-level resources comprise one or more platform-as-a-service (PaaS) offerings provided via the network infrastructure, wherein the mid-level resources are republished to the catalog;\n providing, by the computing system, access from the catalog at the electronic storefront to the mid-level resources for consumption by at least third entities, the at least third entities being different from the at least first entities and from the at least second entities; and\n constructing, by the computing system, high-level resources from the mid-level resources, wherein the high-level resources deliver one or more applications constructed based, at least in part, on at least a portion of the mid-level resources and at least a portion of the low-level resources and are configured by the at least third entities, wherein the high-level resources comprise one or more software-as-a-service (SaaS) offerings provided via the network infrastructure, wherein the high-level resources are published to the catalog and the one or more applications are made available via the electronic storefront.\n\n2. The method of claim 1, wherein the catalog comprises a self service portal.\n\n3. The method of claim 1, wherein at least two of the first, second and third entities are corporate departments.\n\n4. The method of claim 1, wherein at least two of the first, second and third entities are corporate entities.\n\n5. The method of claim 1, further comprising:\n providing access from the catalog to the high-level resources for consumption by at least fourth entities.\n\n6. The method of claim 1, wherein payment as between the third and second entities and as between the second and first entities is handled, wherein a selling price for selling the published high-level resources includes at least a reimbursement of a purchase price for purchasing the low-level resources.\n\n7. The method of claim 1, wherein the network infrastructure includes at least one of a computing device, a server, a client, a router, a hub, a firewall, a personal computer, a communication device, a routing device, an active device, or a passive device.\n\n8. A method comprising:\n accessing, by a computing system, lower-level resources from a self service portal, wherein the lower-level resources deliver one or more operating system instances, wherein the lower level resources comprise at least one of an infrastructure-as-a-service (IaaS)\noffering published by a first entity or a platform-as-a-service (PaaS) offering published by a second entity, and wherein the self service portal is presented at an electronic storefront;\n\nconsuming, by the computing system, the lower level resources including the one or more operating system instances;\n\nconstructing, by the computing system, from the lower level resources, at least higher level resources, wherein the higher level resources are constructed based, at least in part, on adding one or more higher level components to the lower-level resources and configuring the one or more higher level components added to the lower-level resources, wherein the higher level resources comprise at least one of the platform-as-a-service (PaaS) offering published by the second entity based on the infrastructure-as-a-service (IaaS) offering or a software-as-a-service (SaaS) offering published by a third entity based on the platform-as-a-service (PaaS) offering, wherein the infrastructure-as-a-service (IaaS), the platform-as-a-service (PaaS) offering, and the software-as-a-service (SaaS) offering are provided via a network infrastructure; and\n\npublishing, by the computing system, the higher level resources to the self service portal at the electronic storefront for consumption by others, wherein the higher level resources deliver at least one of an environment or an application constructed based, at least in part, on at least a portion of the lower-level resources, wherein the at least one of the environment or the application is made available via the electronic storefront.\n\n9. The method of claim 8, further comprising providing the lower level resources for purchase.\n\n10. The method of claim 9, further comprising providing the published higher level resources for sale.\n\n11. The method of claim 8, wherein payment as between the third entity and the second entity and as between the second entity and the first entity are handled, wherein a selling price for selling the republished higher-level resources includes at least a reimbursement of a purchase price for purchasing the lower level resources.\n\n12. The method of claim 8, wherein the first entity is different from the second entity.\n\n13. The method of claim 8, wherein at second entity is different from the third entity.\n\n14. The method of claim 8, wherein the network infrastructure includes at least one of a computing device, a server, a client, a router, a hub, a firewall, a personal computer, a communication device, a routing device, an active device, or a passive device.\n\n15. A system comprising:\n\n- at least one processor; and\n- a memory storing instructions that, when executed by the at least one processor, cause the system to perform:\n\n receiving low-level resources for delivering one or more operating system instances, wherein at least first entities publish the low-level resources to a catalog presented at an electronic storefront, and wherein the low level resources comprise one or more infrastructure-as-a-service (IaaS) offerings provided via a network infrastructure;\n\n providing access from the catalog at the electronic storefront to the low-level resources for consumption by at least second entities, the at least second entities being different from the at least first entities;\n\n constructing mid-level resources from the low-level resources, wherein the mid-level resources are constructed based, at least in part, on one or more middleware components being added to the low-level resources by the at least second entities and being configured by the at least second entities, wherein the mid-level resources comprise one or more platform-as-a-service (PaaS) offerings provided via the network infrastructure, wherein the mid-level resources are republished to the catalog;\n\n providing access from the catalog at the electronic storefront to the mid-level resources for consumption by at least third entities; and\n\n constructing high-level resources from the mid-level resources, wherein the high-level resources deliver one or more applications constructed based, at least in part, on at least a portion of the mid-level resources and at least a portion of the low-level resources and are configured by the at least third entities, wherein the high-level resources comprise one or more software-as-a-service (SaaS) offerings provided via the network infrastructure, wherein the high-level resources are published to the catalog and the one or more applications are made available via the electronic storefront.\n\n16. The system of claim 15, wherein the first entities and the second entities are not the same.\n\n17. The system of claim 15, wherein the second entities and the third entities are not the same.\n\n18. The system of claim 15, wherein the network infrastructure includes at least one of a computing device, a server, a client, a router, a hub, a firewall, a personal computer, a communication device, a routing device, an active device, or a passive device.\n\n19. The system of claim 15, wherein payment as between the second entities and the third entities and payment as between the first entities and the second entities are handled at least in part by the system.\n\n20. The system of claim 15, wherein a selling price for selling the published higher level resources includes at least a reimbursement of a purchase price for purchasing the lower level resources."}}},{"rowIdx":65,"cells":{"id":{"kind":"string","value":"31fc8b62540a7714beb5b480dcfc4128d735a530"},"text":{"kind":"string","value":"NOTE\n\nProgress is an ongoing commitment at Giddings & Lewis. We continually strive to offer the most advanced products in the industry; therefore, information in this document is subject to change without notice. The illustrations and specifications are not binding in detail. Giddings & Lewis shall not be liable for any technical or editorial omissions occurring in this document, nor for any consequential or incidental damages resulting from the use of this document.\n\nDO NOT ATTEMPT to use any Giddings & Lewis product until the use of such product is completely understood. It is the responsibility of the user to make certain proper operation practices are understood. Giddings & Lewis products should be used only by qualified personnel and for the express purpose for which said products were designed.\n\nShould information not covered in this document be required, contact the Customer Service Department, Giddings & Lewis, 666 South Military Road, P.O. Box 1658, Fond du Lac, WI 54936-1658. Giddings & Lewis can be reached by telephone at (414) 921-7100.\n\n401-52838-01\nVersion 2.0\n17-92\n# TABLE OF CONTENTS\n\n<table>\n<thead>\n<tr>\n<th>SECTION</th>\n<th>PAGE</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>PART ONE - LADDER DEVELOPMENT AND DOCUMENTATION</strong></td>\n<td></td>\n</tr>\n<tr>\n<td><strong>Section 1 - Introduction</strong></td>\n<td></td>\n</tr>\n<tr>\n<td>1.1 Introduction</td>\n<td>1-1</td>\n</tr>\n<tr>\n<td>1.2 Description</td>\n<td>1-1</td>\n</tr>\n<tr>\n<td>1.3 System Requirements</td>\n<td>1-2</td>\n</tr>\n<tr>\n<td>1.4 PC400, PiC409, PiC49</td>\n<td>1-2</td>\n</tr>\n<tr>\n<td>1.5 Keyboard Stickers</td>\n<td>1-2</td>\n</tr>\n<tr>\n<td><strong>Section 2 - Start-Up</strong></td>\n<td></td>\n</tr>\n<tr>\n<td>2.1 Backing Up The GLLADD Software</td>\n<td>2-1</td>\n</tr>\n<tr>\n<td>2.1.1 Systems With Two Floppy Disk Drives</td>\n<td>2-1</td>\n</tr>\n<tr>\n<td>2.1.2 Systems With One Floppy And One Hard Disk</td>\n<td>2-3</td>\n</tr>\n<tr>\n<td>2.2 Initializing the GLLADD Software</td>\n<td>2-5</td>\n</tr>\n<tr>\n<td>2.2.1 GLLADD Initialization Parameters</td>\n<td>2-5</td>\n</tr>\n<tr>\n<td>2.2.2 Changing The Initialization File Parameters</td>\n<td>2-8</td>\n</tr>\n<tr>\n<td>2.3 Main Menu (G&L PiC Ladder Development System)</td>\n<td>2-8</td>\n</tr>\n<tr>\n<td>2.4 Ladder Names</td>\n<td>2-9</td>\n</tr>\n<tr>\n<td><strong>Section 3 - Ladder Diagram Editor/Compiler</strong></td>\n<td></td>\n</tr>\n<tr>\n<td>3.1 Instruction Set</td>\n<td>3-1</td>\n</tr>\n<tr>\n<td>3.2 Entering the GLLADD Ladder Editor/Compiler</td>\n<td>3-1</td>\n</tr>\n<tr>\n<td>3.3 Creating A New LDN</td>\n<td>3-3</td>\n</tr>\n<tr>\n<td>3.3.1 Entering Ladder Diagram Circuits</td>\n<td>3-4</td>\n</tr>\n<tr>\n<td>3.3.2 Entering Statements</td>\n<td>3-5</td>\n</tr>\n<tr>\n<td>3.3.3 Leaving The Insert Mode</td>\n<td>3-7</td>\n</tr>\n<tr>\n<td>3.4 Display Mode</td>\n<td>3-7</td>\n</tr>\n<tr>\n<td>3.5 Search Mode</td>\n<td>3-8</td>\n</tr>\n<tr>\n<td>3.6 Inserting Blocks Into An Existing LDN</td>\n<td>3-9</td>\n</tr>\n<tr>\n<td>3.7 Modifying Blocks</td>\n<td>3-10</td>\n</tr>\n<tr>\n<td>3.7.1 Modifying A Ladder Diagram Circuit (LDC)</td>\n<td>3-10</td>\n</tr>\n<tr>\n<td>3.7.1.1 Inserting Elements Into An LDC</td>\n<td>3-16</td>\n</tr>\n<tr>\n<td>3.7.1.2 Modifying Elements In An LDC</td>\n<td>3-17</td>\n</tr>\n<tr>\n<td>3.7.2 Modifying Statements</td>\n<td>3-17</td>\n</tr>\n<tr>\n<td>3.7.3 Exiting The Edit Mode</td>\n<td>3-19</td>\n</tr>\n<tr>\n<td>3.8 Copying Sections Of The LDN</td>\n<td>3-19</td>\n</tr>\n<tr>\n<td>3.9 Moving Sections Of The LDN</td>\n<td>3-20</td>\n</tr>\n<tr>\n<td>3.10 Deleting Sections Of An LDN</td>\n<td>3-22</td>\n</tr>\n<tr>\n<td>3.11 Auxiliary Functions</td>\n<td>3-23</td>\n</tr>\n<tr>\n<td>3.11.1 Reinitialize</td>\n<td>3-23</td>\n</tr>\n<tr>\n<td>3.11.2 Allocate Memory</td>\n<td>3-23</td>\n</tr>\n<tr>\n<td>3.11.3 Name Ladder</td>\n<td>3-24</td>\n</tr>\n<tr>\n<td>3.11.4 Message Formatter</td>\n<td>3-24</td>\n</tr>\n<tr>\n<td>3.11.4.1 Creating New Messages</td>\n<td>3-24</td>\n</tr>\n<tr>\n<td>3.11.4.2 Displaying Messages</td>\n<td>3-25</td>\n</tr>\n</tbody>\n</table>\n### Section 3 - Ladder Diagram Editor/Compiler (continued)\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Title</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>3.11.4.3</td>\n<td>Deleting A Message</td>\n<td>3-26</td>\n</tr>\n<tr>\n<td>3.11.4.4</td>\n<td>Renumbering Messages</td>\n<td>3-26</td>\n</tr>\n<tr>\n<td>3.11.4.5</td>\n<td>Editing Messages</td>\n<td>3-26</td>\n</tr>\n<tr>\n<td>3.11.4.6</td>\n<td>Configuring The CRT</td>\n<td>3-27</td>\n</tr>\n<tr>\n<td>3.11.5</td>\n<td>Installing Call Routines</td>\n<td>3-27</td>\n</tr>\n<tr>\n<td>3.11.5.1</td>\n<td>Installing Call Routines From Disk</td>\n<td>3-27</td>\n</tr>\n<tr>\n<td>3.11.5.2</td>\n<td>Installing Call Routines From EPROM</td>\n<td>3-28</td>\n</tr>\n<tr>\n<td>3.11.5.3</td>\n<td>Installing Real Time Debug (C912)</td>\n<td>3-30</td>\n</tr>\n<tr>\n<td>3.11.5.4</td>\n<td>Reinstalling Call Routines</td>\n<td>3-30</td>\n</tr>\n<tr>\n<td>3.11.6</td>\n<td>Changing The Timer Increment</td>\n<td>3-30</td>\n</tr>\n<tr>\n<td>3.12</td>\n<td>Exiting The GLLADD Ladder Editor/Compiler</td>\n<td>3-30</td>\n</tr>\n</tbody>\n</table>\n\n### Section 4 - LDN Documeneter\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Title</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>4.1</td>\n<td>Definition Files</td>\n<td>4-2</td>\n</tr>\n<tr>\n<td>4.2</td>\n<td>Adding And Modifying Text</td>\n<td>4-2</td>\n</tr>\n<tr>\n<td>4.2.1</td>\n<td>Contact Labels</td>\n<td>4-4</td>\n</tr>\n<tr>\n<td>4.2.2</td>\n<td>Variable Labels</td>\n<td>4-4</td>\n</tr>\n<tr>\n<td>4.2.3</td>\n<td>Comments</td>\n<td>4-5</td>\n</tr>\n<tr>\n<td>4.2.4</td>\n<td>Headings</td>\n<td>4-6</td>\n</tr>\n<tr>\n<td>4.2.5</td>\n<td>Top Of Page</td>\n<td>4-6</td>\n</tr>\n<tr>\n<td>4.3</td>\n<td>Deleting Text</td>\n<td>4-6</td>\n</tr>\n<tr>\n<td>4.4</td>\n<td>Copying Text</td>\n<td>4-8</td>\n</tr>\n<tr>\n<td>4.5</td>\n<td>Moving Text</td>\n<td>4-9</td>\n</tr>\n</tbody>\n</table>\n\n### Section 5 - Listing A Documented LDN\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Title</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>5.1</td>\n<td>Cross Reference Information</td>\n<td>5-1</td>\n</tr>\n<tr>\n<td>5.1.1</td>\n<td>Contact Cross References In The LDN</td>\n<td>5-1</td>\n</tr>\n<tr>\n<td>5.1.2</td>\n<td>Coil Cross References In The LDN</td>\n<td>5-2</td>\n</tr>\n<tr>\n<td>5.1.3</td>\n<td>Cross References At The End Of The LDN</td>\n<td>5-3</td>\n</tr>\n</tbody>\n</table>\n\n### Section 6 - Disk File Handler\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Title</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>6.1</td>\n<td>Backup Files</td>\n<td>6-1</td>\n</tr>\n<tr>\n<td>6.2</td>\n<td>Disk File Handler Menu</td>\n<td>6-2</td>\n</tr>\n<tr>\n<td>6.3</td>\n<td>Short Directory</td>\n<td>6-3</td>\n</tr>\n<tr>\n<td>6.4</td>\n<td>Long Directory</td>\n<td>6-3</td>\n</tr>\n<tr>\n<td>6.5</td>\n<td>Deleting Files</td>\n<td>6-4</td>\n</tr>\n<tr>\n<td>6.6</td>\n<td>Changing Filenames</td>\n<td>6-5</td>\n</tr>\n<tr>\n<td>6.7</td>\n<td>Copying Files</td>\n<td>6-6</td>\n</tr>\n<tr>\n<td>6.8</td>\n<td>Changing File Extensions</td>\n<td>6-7</td>\n</tr>\n</tbody>\n</table>\nPART TWO - PiC SUPPORT FUNCTIONS\n\nSection 7 - PiC409 AUX 1 Support\n\n7.1 Introduction .............................................. 7-1\n7.2 AUX 1 Software On The PiC ......................... 7-1\n7.3 Using The AUX 1 Support Function ................. 7-1\n7.4 Creating A User Authorization Code ............... 7-2\n7.5 AUX 1 Menu Selection ................................. 7-2\n7.6 Redirecting Communications From The Loader Port\n To The Terminal Port .................................... 7-3\n7.7 Changing The Authorization Code Functions ...... 7-4\n7.8 Leaving And Returning To the AUX 1 Mode ....... 7-5\n7.9 Loading, Recording And Verifying LDN’s On Disk 7-5\n7.9.1 Loading LDN’s From Disk Into The PiC .......... 7-5\n7.9.2 Verifying LDN’s On Disk And The PiC .......... 7-5\n7.9.3 Recording LDN’s From The PiC Onto Disk ....... 7-6\n7.10 Loading, Recording And Verifying LDN’s\n Using A STR LINK II or III Tape Device .......... 7-6\n7.11 Installing Call Routines From Disk ................ 7-6\n7.12 Variable And Control Relay Backup ............... 7-7\n7.12.1 Saving Data On Disk ................................. 7-7\n7.12.2 Loading Data From Disk Or Tape ................. 7-8\n\nSection 8 - GLLADD Auxiliary Functions\n\n8.1 Control Panel Support ................................. 8-1\n8.1.1 Terminal Mode ....................................... 8-3\n8.1.2 Mass Storage Mode ................................. 8-3\n8.1.2.1 Transferring LDN’s Between\n The Computer And The PiC ......................... 8-3\n8.1.2.2 Transferring Data Files Between\n The Computer And The PiC ......................... 8-3\n8.1.3 Installing Call Routines ........................... 8-4\n8.2 Using A STR LINK II Or III ......................... 8-4\n8.2.1 Connecting The STR LINK II\n Or III To The Computer .............................. 8-5\n8.2.2 Saving An LDN From Tape Onto Disk .......... 8-5\n8.2.3 Saving An LDN From Disk Onto Tape ............ 8-5\n\nPART THREE APPENDIX\n\nAPPENDIX A - GLLADD Menu Structure\nAPPENDIX B - Connecting Cable\nAPPENDIX C - Index Of Illustrations\nPART ONE - LADDER DEVELOPMENT AND DOCUMENTATION\nSECTION 1 - INTRODUCTION\n\n1.1 INTRODUCTION\n\nThe Giddings and Lewis Ladder Development System (GLLADD) is a group of software programs for the IBM Personal Computer or IBM compatible computers. These programs are designed to support the Giddings and Lewis Programmable Industrial Computers (PiC's). GLLADD provides users with ladder diagram development and documentation capabilities and remote control of the PiC.\n\nFor your own protection, a backup copy of the GLLADD disk should be made as soon as possible. For disk copying instructions, refer to Section 2 in this manual and to the manual supplied with your disk operating system (DOS) software. Store the original GLLADD disk in a safe place. Use only the backup copy for ladder development and documentation.\n\nThe GLLADD disk is supplied with a write protect tab to prevent the software from being erased. DO NOT REMOVE THIS TAB. The backup disk however, must be \"written to\" during the initialization procedure. Do not put a write protect tab on the backup copy of GLLADD until after the initialization procedure described in Section 2.2 is completed.\n\n1.2 DESCRIPTION\n\nGLLADD is menu driven and easy to use. The software, ladder diagrams and documented ladder files will be saved on floppy or hard disks for easy storage and fast retrieval. GLLADD will perform the following functions:\n\n1. Provide for creating, editing and compiling LDN's on an IBM PC or compatible computer.\n\n2. Document and cross reference Ladder Diagram Networks (LDN's).\n\n3. Output documented LDN's to a printer or disk.\n\n4. Provide for renaming, copying and deleting LDN's and definition files on disk.\n\n5. Keep a directory of LDN's on disk.\n\n\n7. Provide for remote control of the PiC using the AUX 1 mode.\n\n8. Load and install G&L Call Routines from a disk.\n\nFIGURE 1.1 WRITE PROTECT TAB\n9. Transfer LDN and data files between a disk and a G&L PiC.\n\n10. Transfer LDN's and data files between a disk and a STR/LINK II or STR/LINK III tape loader.\n\n1.3 SYSTEM REQUIREMENTS\n\nThe following items are required if GLLADD (version 2.0 or higher) is to be used.\n\n1. One IBM Personal Computer or compatible system with the following features:\n - Two disk drives\n - At least 192K of internal memory (256K or more preferred).\n - An RS-232C port (COM1 or COM2)\n - A printer port\n\n2. Disk operating system software (IBM PC DOS or MS DOS) and DOS manual.\n\n3. One GLLADD Software Disk.\n\n4. Floppy disks or hard disk for file storage and backup.\n\n5. One Giddings and Lewis Programmable industrial Computer (PiC).\n\n6. A printer with at least 80 characters per line. A wide bed printer with 136 characters per line is recommended.\n\nOptional:\n\n1. STR LINK II cassette or STR LINK III data cartridge tape loader\n\n2. Ladder Diagrams on tape that require documentation.\n\n\n4. Call Routine software on floppy disk.\n\n1.4 PC400, PiC409 AND PiC49\n\nGLLADD works primarily with the G&L PiC409 and PiC49. The software is capable of documenting a PC400 LDN if the LDN is recorded on tape using a STR LINK II or STR LINK III tape loader. However, the computer cannot be used as a terminal or editor for the PC400.\n\nThe references to the PiC409 are the same for the PiC49 and the PiC409. If you have a PiC49, use it the same way that a PiC409 is used.\n\n1.5 KEYBOARD STICKERS\n\nA set of keyboard stickers is supplied with each new GLLADD package. These stickers show the ladder programming symbols associated with a specific key. Remove any dirt or moisture from the computer keys. Remove the stickers from the backing sheet and adhere them to the tops of the corresponding keys on the computer keyboard.\nSECTION 2 - START-UP\n\n2.1 BACKING UP THE GLLADD SOFTWARE\n\nBefore running GLLADD, the user must create a backup copy on either a floppy or a hard disk. In addition to the GLLADD software files, the backup disk must also contain certain DOS (disk operating system) files. Refer to Section 2.1.1 if your system uses two floppy disk drives. Refer to Section 2.1.2 if your system uses one floppy and one hard disk drive.\n\nNOTE\n\nThe user must be familiar with the G&L Programmable industrial Computer and Ladder Diagram programming to use the GLLADD software. Refer to the PiC409 Family Programming Manual for programming and operating instructions.\n\nBefore using GLLADD, the operator should also be familiar with the computer's DOS (disk operating system). It is beyond the scope and intent of this manual to provide instructions for using DOS. Please refer to your DOS manual when DOS commands are required.\n\n2.1.1 Systems With Two Floppy Disk Drives\n\nTo format a file disk and create a backup copy of GLLADD onto another floppy disk, follow the steps listed as follows:\n\n1. Insert your DOS disk into Drive A.\n2. Insert your DOS disk into Drive A.\n3. Insert a blank disk into Drive B.\n4. Format the blank disk in Drive B by entering \"FORMAT B:/S\" and a return after the A> prompt.\n\nStart-Up\n\nIMPORTANT\n\nThe FORMAT command will erase all of the memory on any disk including a hard disk. DO NOT FORMAT A DISK UNLESS IT HAS NEVER BEEN USED BEFORE OR IF THE DISK DOES NOT CONTAIN ANY INFORMATION THAT HAS TO BE SAVED.\n\n4. When the formatting is complete, remove the disk from Drive B and set it aside. This disk will be used for LDN storage and the documentation database.\n\nThe computer will ask if you wish to format another disk. Press the Y (yes) key and insert another blank disk into Drive B. Once formatted, this disk will be used as the GLLADD backup disk.\n\n5. The computer will ask you again if you wish to format another disk. Press the N (no) key. The A> prompt will reappear.\n\n6. Add a CONFIG.SYS file to the backup disk in Drive B by entering the following lines after the A> prompt.\n\n COPY CON: B:CONFIG.SYS\n (return)\n BUFFERS=20 (return)\n (press the F6 key) (return)\n\nUsing less than 20 buffers will cause GLLADD to run inefficiently with a slow response time.\n\n7. (optional) By adding an AUTOEXEC.BAT file to the backup disk, the computer will automatically start up the GLLADD software when the GLLADD backup disk is inserted into drive A and the power is turned on.\nTo add an AUTOEXEC.BAT file to the backup disk in Drive B, enter the following lines after the A> prompt.\n\nCOPY CON: B:AUTOEXEC.BAT (return)\nGLLADD (return) (press the F6 key) (return)\n\nTo add more lines to the AUTOEXEC.BAT file, such as the time from a battery backed clock or RAM disk information etc., refer to the section on BATCH commands in the DOS manual.\n\n8. Remove the DOS disk from Drive A and return it to its storage place.\n\n9. Remove the backup disk from Drive B and insert it into Drive A.\n\n10. Insert the G&L GLLADD disk into Drive B.\n\n11. Copy all of the files from the GLLADD disk in Drive B to the backup disk in drive A by entering the following line after the A> prompt.\n\nCOPY B:*.* /V\n\nWhen copying the GLLADD files, be sure to specify \".*.*\" (asterisk/period/asterisk) instead of a file name and extension. This allows you to copy all of the GLLADD files with a single COPY command.\n\nThe \"/V\" parameter in the COPY command is used to verify that the COPY operation is executed properly.\n\n12. Remove the GLLADD disk from drive B and store it in a safe place.\n\nPage 2-2\n13. Insert the formatted file disk set aside for LDN storage and the documentation database into Drive B.\n\n14. Type \"GLLADD\" after the \"A>\" prompt and press the return key to run GLLADD.\n\nFrom now on, each time GLLADD is to be used, insert the GLLADD backup disk into Drive A and the storage disk into Drive B. Turn the power on.\n\nIf you created an \"AUTOEXEC.BAT\" file (see step 7), the GLLADD software will start up automatically. Otherwise, type \"GLLADD after the DOS \"A>\" prompt to start up the GLLADD software.\n\n---\n\n**IMPORTANT**\n\nAfter copying the GLLADD files onto a backup disk, store the original GLLADD disk in a safe place. It should only be used to make another backup copy if the first copy you made fails.\n\n---\n\n2.1.2 Systems With One Floppy and One Hard Disk\n\nIf you are using a computer with a single floppy and a single hard (fixed) disk drive, there are several options available. The hard disk can be used to store any combination of the GLLADD software, LDN and documentation database files, GLLADD ladder listings, data files and G&L Call Routines.\n\nWe recommend using a subdirectory on the hard disk to be used only for GLLADD files. Use the DOS MD (make directory) command to create the subdirectory.\n\nUse the DOS COPY command to copy all of the files from the G&L GLLADD disk into this subdirectory.\n\n---\n\nStart-Up\nNOTE\n\nAt least 20 disk buffers (BUFFERS=20) are required for the GLLADD software to operate efficiently. Create a CONFIG.SYS file in your hard drive default directory that specifies at least 20 buffers (BUFFERS=20).\n\nIf any other application programs on your hard disk cannot work with 20 buffers, you may wish to use a floppy disk for the GLLADD backup disk instead. If this is the case, refer to Section 2.1.1. Otherwise, refer to your DOS manual for setting up a config.sys file.\n\nIMPORTANT\n\nAfter copying the GLLADD files onto a backup disk, store the original GLLADD disk in a safe place. It should only be used to make another backup copy if the first copy you made fails.\n\nThe FORMAT command will erase all of the memory on any disk including a hard disk. DO NOT FORMAT A DISK UNLESS IT HAS NEVER BEEN USED BEFORE OR IF THE DISK DOES NOT CONTAIN ANY INFORMATION THAT HAS TO BE SAVED.\n\n---\n\nPERSONAL COMPUTER HARD DISK\n\nROOT DIRECTORY\n\nGLLADD SUBDIRECTORY\n\nSYSTEM FILES\n\n- GLLADD Software\n- Call Routines\n\nWORKING FILES\n\n- Ladder (.LDN) Files\n- Definition (.DEF) Files\n- List (.LIS) Files\n- Data (.DAT) Files\n- Scratch (.SCR) Files\n\n---\n\nFIGURE 2-2 SUGGESTED HARD DISK CONFIGURATION\n2.2 INITIALIZING THE GLLADD SOFTWARE\n\nWhen running the GLLADD software for the first time, the word GLLADD will appear on the monitor with the version number and copyright notice.\n\nThe monitor will then display some descriptive information along with instructions for setting up an initialization file called GLLADD.INT. The initialization parameters of this file configure the software to fit the particular hardware for each user.\n\nThe initialization file is set up only once. After GLLADD is initialized, the instructions for setting up the file will not be run again.\n\nAnswer all of the initialization questions carefully. If the parameter to be used is the same as the one in the brackets ([ ]), the return key may be pressed without entering the parameter. This parameter will be entered into the file automatically.\n\nAfter the initialization process is complete, the monitor will display the main menu. From now on, whenever the user inserts the GLLADD disk and turns on the computer, the software will go straight from the title display to the main menu.\n\nNOTE\n\nThe write protect notch must not be covered during the initialization procedure. However, when the procedure is completed, cover the notch with a write protect tab to prevent accidental erasure of your disk files.\n\n2.2.1 GLLADD Initialization Parameters\n\nThe specific questions asked by the GLLADD software to create the initialization file are as follows:\n\n1. GLLADD will build ladder memory disk files '<laddername>.LDN', ladder documentation definition files '<laddername>.DEF' and data files '<filename>.DAT. Please indicate the disk drive on which these working files are to be built. GLLADD will use the current directory on that drive. The drive in brackets will be used if none other is specified.\n\n Working Drive (a,[b],c)?\n\nSpecify the disk drive where you intend to store both your ladder diagram and documentation files. If you are using two floppy disk drives, this would be drive B.\n\nIf you are using a system with one hard disk and one floppy disk drive, this would either be drive C (for storage on the hard disk) or drive A (for storage on the floppy disk drive).\n2. **GLLADD** will need to build a scratch file 'GLLADD.SCR', to collect ladder contact cross reference information. Please indicate the disk drive on which this temporary file should be built. **GLLADD** will use the current directory on that drive. The drive in brackets will be used if none other is specified.\n\n**Scratch Drive** (a,[b],c)?\n\nSpecify the disk drive where cross referencing will take place. If you are familiar with using a \"RAM drive\" (using the computer's memory to simulate a disk drive), you can perform the **GLLADD** cross referencing operations in memory many times faster than with a normal disk drive.\n\nIf you choose not to use a \"RAM\" drive, we recommend using the same drive as the working drive for \"GLLADD.SCR\" files.\n\n3. Most personal computers have provisions for more than one serial communications port. Please indicate which port you wish **GLLADD** to use for communications. The value in brackets will be used if none other is specified.\n\n**Communications Port** ([1],2)?\n\nSpecify the serial port (1 or 2) on the personal computer that will be used for communicating with the PiC. This port will be used to transfer LDN's, Call Routines and data as well as to allow the computer to act as a programming terminal for the PiC.\n\n4. **GLLADD** is designed to communicate with the PiC409 at 9600 baud. For some reason it may be desirable to communicate at a slower rate. Please indicate which baud rate you wish **GLLADD** to use to communicate. The value in brackets will be used if none other is specified.\n\n**Baudrate** (110,300,600,1200,4800,[9600])?\n\nThis feature allows you to communicate with the PiC409 or PiC49 at a slower rate. A slower rate may be desirable when using other devices during communications such as a telephone modem. This feature may also be helpful if you experience communications overrun errors at the standard 9600 baud rate.\n5. It is assumed that the line printer being used supports the form feed to be supplied by GLLADD. Please indicate the number of lines to be printed on a page. The value in brackets will be used if none other is specified.\n\nPage Length (11 x 8.5 paper assumed [45])?\n\nThe number of lines per page is determined by the size of the paper you are using and by the number of lines that are printed per inch. Enter the number of lines to be printed on each page and press the return key.\n\n6. A wide bed printer is required for fully documented ladder listings. Please indicate the number of characters to be printed on each line. The value in brackets will be used if none other is specified.\n\nNOTE: Any value less than 100 and GLLADD will not print cross reference information and/or comments to the right of the ladder.\n\nPage Width (11 x 8.5 paper assumed 79-136 [110])?\n\nThe number of characters per line is normally limited by the printer you are using. However, some smaller printers, like the Okidata 82A which normally prints only 80 characters per line, can be configured to print more characters if a condensed typestyle is used.\n\n7. Based on the information you have just entered, the GLLADD software has been configured to support a given printer page size. In addition, the printer hardware itself must also be configured to support this page size, along with form-feed character recognition, and no auto-skip over the perforation. On many printers this configuring is done through a series of control codes which GLLADD will supply at the beginning of each listing. GLLADD has a number of built-in configuring patterns, you may enter your own pattern, or you may choose no configuring pattern.\n\nPlease make your selection.\n\n<F1> Epson FX100.\n<F2> Okidata Microline 82A (10 CPI, 80 columns).\n<F3> Okidata Microline 82A (16.5 CPI, 132 columns).\n<F4> Enter your own pattern.\n<F10> No configuring pattern.\n\nEnter one of the first three patterns or enter a pattern of your own using selection F4. Other printers may be able to use the configurations given here. However, refer to the documentation supplied with your printer for the correct control codes. If you press the F10 key to indicate that no configuring pattern is to be used, a printer cannot be used with the GLLADD software.\n8. GLLADD normally outputs listings directly to the line printer. Although the files may get quite large (in excess of 100k), it might be desirable to output listings to a '<laddername>.LIS' disk file instead of the printer. Please indicate whether output should be re-directed to a '<laddername>.LIS' disk file on the working drive. Direct output to the printer will be assumed if nothing is specified.\n\nOutput to a <laddername>.LIS disk file (y,[n])?\n\nYou may output listings to a disk file instead of a printer. The disk file created will be a standard ASCII text file containing all of the information that would appear in a regular printout.\n\nDisk files are useful if you want to print several copies of a documented ladder without performing the cross referencing operation for each copy. To print from a disk file, use the DOS PRINT commands as described in your DOS manual. The GLLADD software will put the extension \".LIS\" after the ladder name for the disk file.\n\n---\n\nNOTE\n\nThe cross referencing operation requires a substantial amount of disk space. If you have a fairly large ladder diagram and/or definition file, you may need to use a system with a hard (fixed) disk. If you use a floppy disk, use a blank, formatted, double-sided, high-density disk for maximum storage space.\n\n2.2.2 Changing the Initialization File Parameters\n\nIf at any time the initialization file parameters have to be changed, the initialization process can be repeated by deleting the GLLADD.INT file. This is accomplished with the following procedure:\n\n1. Remove the write protect tab from the backup disk and start up GLLADD.\n\n2. With the Main Menu on the screen, press the F10 key. The computer will ask \"Do you really want to return to DOS\". Enter \"Y\" (yes).\n\n3. When the prompt A> appears, type \"DEL GLLADD.INT\" and press the return key.\n\n4. The A> prompt will reappear. Type \"GLLADD\". The GLLADD software will repeat the initialization process as described in the previous section.\n\n2.3 MAIN MENU (G&L PiC Ladder Development System)\n\nThe main menu is a graphic display of the ten function keys found on the left side of a computer keyboard (non-IBM computers may have function keys in a different area). While viewing the display, you will notice that certain function keys are identified with short, descriptive titles. Press the \"Help\" function key (F9). A more detailed description will appear to the side of each function key used in the main menu.\nNOTE\n\nIf you press the \"Abort\" function key, F10, while the main menu is displayed, the computer will ask you if you wish to return to DOS (disk operating system). If you answer Y (yes), the computer will leave GLLADD and return to DOS. When you wish to return to GLLADD from DOS, simply type \"GLLADD\" after the prompt \"A>\". The title display, followed by the main menu, will reappear on the screen.\n\nSelecting any of the function keys used in the main menu besides the \"Help\" or \"Abort\" keys, will take you to different GLLADD functions and menus. GLLADD menus use the same keypad format as the main menu but assign different functions to the keys. Only the \"Help\" and \"Abort\" functions remain. The \"Help\" function provides a more detailed description of the function keys. The \"Abort\" function will return you to the menu you were previously in.\n\nFollow each menu carefully and use the help function key (F9) when additional information is needed. GLLADD will instruct you through each procedure.\n\nG&L PiC Ladder Development System\n\n<table>\n<thead>\n<tr>\n<th>Edit/Compile Ladder</th>\n<th>Edit Document Database</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F1</td>\n<td>F2</td>\n</tr>\n<tr>\n<td>List Documen. Ladder</td>\n<td>Disk File Handler</td>\n</tr>\n<tr>\n<td>F3</td>\n<td>F4</td>\n</tr>\n<tr>\n<td>PiC409 Aux. 1 Support</td>\n<td>Aux. F6 Funcs.</td>\n</tr>\n<tr>\n<td>F5</td>\n<td>F7</td>\n</tr>\n<tr>\n<td>F8</td>\n<td>F9 Help</td>\n</tr>\n<tr>\n<td>F10 <Alt> Abort</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nSelect an operation via the function keys.\n\nFIGURE 2-3 MAIN MENU\n\n2.4 LADDER NAMES\n\nThe GLLADD user must identify each Ladder Diagram Network (LDN) with a ladder name. Ladder names may be up to eight characters in length. The characters permitted for a ladder name include the entire alphabet (A-Z), the numerals 0-9, and the following symbols and punctuation marks:\n\nStart-Up\n\n$ & @ ! % ' ( ) - / ______\n\nA new ladder name is required when an LDN is transferred from the PiC to the computer or from a STR LINK tape loader to the computer. After an LDN is saved on disk, the user must identify the LDN by its ladder name before proceeding with any operations that affect the LDN and its documentation.\nBecause GLLADD is capable of storing several LDN's and their documentation on a single disk, files are used by the computer to effectively locate and process information. GLLADD files are grouped according to their ladder names.\n\nThe GLLADD software will create several files which use the same ladder name. These files include the LDN itself, a definition file containing text for headings, labels and comments and a temporary \"scratch\" file used for cross referencing. When GLLADD documents an LDN, it combines these three files and sends the information to a printer. For a more complete description of the files used by GLLADD, refer to Section Six - Disk File Handler.\nThe GLLADD Ladder Editor/Compiler allows the programmer to create and edit Ladder Diagram Networks (LDN's) on an IBM or IBM compatible personal computer. No connection to the G&L Pic409 or Pic49 is required when creating an LDN.\n\nThe editing functions are much more comprehensive with the GLLADD software than they are with the standard Pic programming modules. The different modes of the GLLADD Editor/Compiler are listed below:\n\nInsert Mode - This mode is for entering new LDN's or inserting new blocks into existing LDN's. A block can be a complete ladder type circuit or one of the four G&L Pic programming statements.\n\nDisplay Mode - The entire LDN, or any portion of it, can be viewed on the computer screen using this mode. If the LDN is too large to fit on the screen, this mode can be used to \"scroll\" down through the LDN.\n\nModify Mode - The programmer can modify individual blocks in an LDN. With the modify mode, individual elements within a ladder rung can be added, modified or deleted without retyping the entire block.\n\nSearch Mode - With this feature, the programmer can search for every occurrence of an individual element in the LDN.\n\nCopy, Move and Delete Modes - These three modes allow the programmer to choose a section of the LDN and either copy that section and duplicate it in another area of the LDN or to move the entire section elsewhere or to delete the section entirely.\n\nAuxiliary Functions - In addition to creating standard LDN circuits and statements, Call Routines and messages will probably need to be added to the program to take full advantage of the Pic's capabilities. The auxiliary functions provide these capabilities on the personal computer without the need to be connected to the Pic.\n\n3.1 INSTRUCTION SET\n\nRefer to the Pic409 Family Programming Manual for information regarding the format of the Ladder Diagram Networks (LDN's) and the instruction set.\n\n3.2 ENTERING THE GLLADD LADDER EDITOR/COMPILER\n\nTo enter the GLLADD Editor/Compiler, display the Main Menu on the computer screen and press the F1 (Edit/Compile Ladder) function key. The following message will appear:\n\nEnter the ladder name (<F9> for help, <F10> to abort):\n\nAt this point you must enter a name for the LDN. The ladder name may contain any combination of up to 8 alphanumeric characters and certain symbols. Press the F9 (Help) function key for a list of all the valid ladder name characters.\n\nAfter entering the ladder name, press the return key. If you are creating a new LDN or if this ladder name does not already exist on your file disk, the following message will appear:\n\nWarning, cannot open B:(your ladder name).LDN as ladder file! A new ladder file will be created.\n\nThis message simply indicates that a file with your ladder name was not found on the disk. and the GLLADD software will create one for you. The next message that will appear is:\nCurrently there are 0 nonvolatile variables indicated. How many nonvolatile variables are desired (starting with variable V0?)\n\nEnter the number of nonvolatile variables desired. The maximum number is 900. Enter a 0 if no nonvolatile variables are desired. Press the return key after entering the correct number.\n\nThe next message that will appear is:\n\nCurrently there are 0 retentive relays indicated. How many retentive relays are desired (starting with relay 512)? Number must be 1000 or less, please reenter.\n\nEnter the number of retentive relays desired. Up to 1000 retentive relays may be designated. Enter a 0 if no retentive relays are desired. Press the Return key after entering the correct number.\n\nYou will then be asked the following question:\n\nThe current LDN size limit is 0 bytes. Enter the desired LDN size limits in K bytes (2-40)?\n\nThe LDN size limit is based on two factors.\n\n1. The amount of user memory in your Pic.\n\n The maximum amount of user memory for a Pic is 40K. However, if you do not have enough memory modules in your Pic master rack, the actual number may be less. Also, if you are using a Call Routine EPROM module in your Pic rack, the maximum user memory available is 36K.\n\n2. The area of user memory designated for Data Storage.\n\n If you require a portion of your user memory for data storage using the Data Storage Call Routines, you must subtract this area from your total user memory area.\n\nFor example: If you have 36K of user memory in your Pic and 10K of that memory is to be reserved for data storage, the LDN size limit will be 26K.\n\nEnter the LDN size limit and press the return key. The following message will appear:\n\nIn which bank will this LDN reside (1-8)?\n\nThis question is related to the Bank Select features of the Pic. If you are not using Bank Select in your Pic enter a \"1\" followed by a return.\n\nIf you are using Bank Select, you can select the bank of memory modules where this LDN will be stored. Enter a bank number number and press the return key. If you are using a Continuous LDN Memory Bank Select Call Routine, enter a \"1\".\n\nNOTE\n\nIf you selected a \"1\", the following request will appear on the screen:\n\nBank 1 selected, enter the highest bank to be used (1-8)?\n\nIf you are not using a Continuous LDN Memory Bank Select Call Routine, enter a \"1\". Otherwise, enter the number of the highest bank that you will be using.\n\nA new menu titled \"Ladder Editor/Compiler\" will appear.\n\nPress the appropriate function key for the desired operation. The different GLLADD Editor/Compiler functions are described in the following sections.\n\nTo exit the GLLADD Editor/Compiler menu, press the F10 (Done) function key. This will save any changes you may have made while in the\nEditor/Compiler and return you to the Main menu.\n\nIf you press the <Alt> <F10> Abort function keys at the same time, the following message will appear:\n\nOperation aborted, ignore any changes (y,n)?\n\nIf you press \"y\" (yes), the software will not save any changes that you may have made in the Ladder Editor/Compiler and will return you to the main menu.\n\nIf you press \"n\" (no), the software will save any changes you may have made and return you to the Main Menu.\n\n3.3 CREATING A NEW LDN\n\nTo create a new LDN, enter the GLLADD Editor/Compiler menu using a new laddername and press the F3 (Insert) function key. This key is used to create new LDN’s or to insert blocks into existing LDN’s.\n\nCreating a new Ladder Diagram Network or LDN on disk using the GLLADD software is similar to entering an LDN directly into the PIC. However, some additional options have been added to make entry easier.\n\nA new display will appear on the screen with this prompt:\n\nInsert after coil/statement #.\n\nPress the letter \"B\". The \"B\" indicates that you wish to insert something after the beginning of the LDN.\n\nWhen the prompt \"I\" appears, you may begin entering the LDN.\n\nDisplay a single ladder circuit, or portions of the entire ladder diagram.\n\nInsert a new ladder circuit into the ladder diagram.\n\nCopy a single circuit, or group of circuits, from one location to another.\n\nDelete a single circuit, or group of circuits, from the ladder diagram.\n\nSearch the ladder diagram for I/O, statement numbers, variables and call names.\n\nModify an existing circuit in the ladder diagram.\n\nMove a single circuit, or group of circuits, from one location to another.\n\nAdditional menu items for functions such as name, allocate and install calls.\n\nSelect an operation via the function keys.\n\nFIGURE 3.1 LADDER EDITOR/COMPILER MENU\n3.3.1 Entering Ladder Diagram Circuits\n\nTo enter an LDC (ladder diagram circuit), press the letter \"F\" for a normally open contact ( - ) or the letter \"G\" for a normally closed ( - ) contact. The appropriate symbol will appear on the screen with the cursor directly above it. Enter the contact number.\n\nAdditional contacts can be entered in the same manner by pressing the letters \"F\" or \"G\" depending upon the type of contact and by entering the contact number.\n\nBranches to a lower rung are entered by pressing the letter \"R\". After entering the last contact and/or branch in the top rung, the rung must be terminated with a regular coil or a timer coil.\n\nTo enter a regular coil ( - ( )- ), press the letter \"T\". When the coil symbol appears, enter the coil number. When the correct number is entered press the return key to terminate the rung.\n\nTo enter a time delay to energize (TE) coil, press the letter \"Y\". For a time delay to de-energize (TD) coil, press the letter \"H\". When the symbol (TE) or (TD) appears, enter the number of the timer coil and press the return key.\n\n\n\n**Figure 3.2 Example Ladder Diagram Circuits (LDC's)**\nThe cursor will drop below the coil symbol after the prompt: \"TIME = \". Enter an integer value from 0 through 65535. This number indicates the number of timer increments the timer coil will use. Each timer increment will be either 10 milliseconds or 100 milliseconds long. See Section 3.11.6 for information regarding selecting the timer increment.\n\nTo terminate the rung, press the return key after entering the number of time increments.\n\nIf the top rung contains no branches to a lower rung the LDC is now complete and the prompt \"!\" will appear again. At this point a new block may be entered.\n\nHowever, if the top rung contains a branch to a lower rung, the cursor will drop below the first contact of the LDC to await the entry of another rung. The procedure for entering contacts and branches is the same for the lower rungs except that no coil entry is made. Instead, when the end of a lower rung is reached, pressing the return key will terminate that rung with the branch from a rung above it.\n\nAn LDC may have a maximum of eight rungs. Each rung may have a maximum of seven contacts. Only one coil at the end of the top rung is allowed. All of the rules for branching must be followed. The GLLADD software will not accept incorrect entries.\n\n### 3.3.2 Entering Statements\n\nStatements are also entered after the \"!\" prompt using the sequences shown below. The GLLADD software will enter many of the characters for you. The actual keystroke sequences are illustrated in the boxes below the example statements.\n\n\n\nThe keystroke sequence needed for this statement is as follows.\n\n```\n2 3 0 0 [-] [- 2 0] THEN LET V1 = 1000\n```\n\n**FIGURE 3.3 LET STATEMENT EXAMPLE**\nThe keystroke sequence needed for this statement is as follows.\n\n```\n2 3 1 0 [-] [-] 2 . 1 SET 1 . 5 :: V . 5 = 6 . 4\n```\n\n\"F\" or \"G\" Key \"C\" Key\n\n**FIGURE 3.4 SET STATEMENT EXAMPLE**\n\nThe keystroke sequence needed for this statement is as follows.\n\n```\n2 3 2 0 [-] [-] 4 5 GOTO 5 0 0\n```\n\n\"F\" or \"G\" Key \"X\" Key\n\n**FIGURE 3.5 GOTO STATEMENT EXAMPLE**\n\nThe keystroke sequence needed for this statement is as follows.\n\n```\n2 3 3 0 [-] [-] 1 0 0 0 CALL C 9 1 2 ( 2 9\n```\n\n\"F\" or \"G\" Key \"S\" Key\n\n**FIGURE 3.6 CALL STATEMENT EXAMPLE**\nNOTE\n\nCall Routines must be installed before their names can be used in a CALL statement. Refer to Section 3.11.5 for instructions on installing Call Routines from diskette or EPROM.\n\nNOTE\n\nIncorrect entries can be deleted before an LDC or statement is terminated. The different delete keys available are as follows:\n\nClear Element (F7 Key) - To delete an entire element from an LDC or a statement while in the insert mode, press the F7 key. Individual elements include: contacts, coils, variables, branches, state numbers, variables, Call Routine names and Call Routine parameters. Each time this key is pressed, the last element entered will be cleared. Elements are cleared from right to left beginning with the lowest rung and moving upward. After the incorrect elements are cleared, new ones may be entered in the usual manner.\n\nDelete a Single Character (Backspace Key) - To delete a single character instead of an entire element, press the backspace key and reenter the correct character. The backspace key will only clear single characters in a parameter or characters used to identify the elements you are working on, such as contact numbers or Call Routine names. It will not clear the element itself.\n\nClear Line (F8 Key) -- The F8 function key is used to clear an entire statement or LDC rung. This key will work from any location on the rung. However, it cannot be used to clear a previous rung.\n\nPress the return key after entering the statement. This will terminate the statement and advance the cursor to the next line with the prompt \"I\". A new LDC or statement may now be entered.\n\n3.3.3 Leaving The INSERT Mode\n\nYou can leave the INSERT mode at any time by pressing the F10 function key.\n\n3.4 DISPLAY MODE\n\nThe Display Mode allows the PiC user to display the contents of an LDN on the screen. To display an LDN, enter the GLLADD Ladder Editor/Compiler menu and press the F1 (Display) function key. The computer will respond with the message:\n\nDisplay starting at coil/statement #\n\nIf you wish to display the LDN from the very first block enter the letter \"B\" to indicate the beginning of the LDN. If you wish to display the LDN from any other block, enter the coil or statement number of that block.\n\nThe block indicated by your entry will be displayed on the screen. To view the next block, press the space bar. The display will advance one block at a time every time the space bar is pressed. Pressing a numeric key from one through nine will display the same number of blocks as the number on the key.\n\nTo scroll through the rest of the LDN, press the number \"0\". The computer will scroll through the remaining blocks in the LDN and stop after displaying the last one.\n\nPress the F10 (Done) function key to exit the display mode and to return the the Ladder Editor/Compiler menu.\n3.5 SEARCH MODE\n\nThe Search mode is used to quickly locate contacts and coils, variables, statement and Call Routine numbers within an LDN.\n\nTo enter the Search mode, press the F2 (Search) function key from the GLLADD Ladder Editor/Compiler menu. The computer will respond with the message:\n\nSearch for contact/coil, variable, statement, or CALL #:\n\nEnter the number of the element you are searching for and press the return key. The block containing the first occurrence of that element will appear on the screen. The element itself will be highlighted by a large cursor and a choice of other functions will appear at the bottom of the screen. These functions are selected by pressing the corresponding function key on the left side of the keyboard.\n\nSearch for contact/coil, variable, statement, or CALL #100\n\n! 10\n!----] [--------------------------------------------]\n\n100\n\nElement Location\n\nF1 Insert After\nEnter the Insert mode by pressing this key. New blocks may be entered to follow the block currently on display.\n\nF2 Modify Block\nPressing this key, puts the computer in the Modify mode. The block currently on display can be modified as described in Section 3.7 (Modify Blocks).\n\nF3 Move Block\nTo move the block currently on display, press this key. Then enter the number of the block that the block on display will be placed after. Press the return key.\n\nF4 Copy Block\nTo duplicate the block currently on display, press this key. Then enter the number of the block that the duplicate block will be placed after. Press the return key.\n\nFigure 3.7 Search Mode Example\nF5 Delete Block\n\nPress this key to delete the block currently on display.\n\nF6 Backup/Advance\n\nPress this key to change the direction of the search function. If the word \"Backup\" is highlighted, the computer will search for an element from the end of the LDN to the beginning. If the word \"Advance\" is highlighted, the search function will go through the LDN from the beginning to the end.\n\n---\n\nNOTE\n\nThe search direction will automatically change when the beginning or the end of the LDN is encountered.\n\nF7 One Occurrence\n\nTo search for the next occurrence of the element specified, press this key. The computer will search for the element in the direction specified by the F6 key.\n\nF8 One Block\n\nIf the F6 key specifies \"Backup\", press this key to display the previous block in the LDN. If the F6 key specifies \"Advance\", pressing this key will display the next block.\n\nF9 Help\n\nPress this key for a brief description of the Search function keys.\n\nF10 Done/Abort\n\nTo exit the Search mode and execute any changes specified using the Search function keys, press the F10 (Done) key.\n\n3.6 INSERTING BLOCKS INTO AN EXISTING LDN\n\nInserting new blocks into an existing LDN is similar to creating a new LDN. However, when entering the GLLADD Ladder Editor/Compiler menu, specify the name of an LDN that already resides on the data disk. Otherwise a new LDN will be created.\n\nOnce the Ladder Editor/Compiler menu is on the screen, press the F3 (Insert) function key. The computer will respond with the message:\n\nInsert after coil/statement #\n\nTo insert one or more blocks at the very beginning of the LDN, press the letter \"B\". To insert one or more blocks after the very last block, press the letter \"E\".\n\nOne or more blocks can also be inserted after any specific block in the LDN by entering that block’s coil statement number.\n\nType in the blocks as described in Section 3.3 CREATING A NEW LDN. After entering the desired block or series of blocks, press the F10 (Done) function key to return to the Ladder Editor/Compiler menu.\n3.7 MODIFYING BLOCKS\n\nThe Modify mode provides extensive editing capabilities for the PiC programmer. In this mode, the programmer can add, change or delete any of the elements of an individual block (LDC or statement).\n\nTo enter the Modify mode from the GLLADD Ladder Editor/Compiler menu, press the F4 (Modify) function key. The computer will respond with the following message:\n\nModify coil/statement #\n\nEnter the coil number of an LDN or the number of a statement for the block you wish to modify. The screen will display the block to be modified and a selection of different modify functions.\n\n3.7.1 Modifying A Ladder Diagram Circuit (LDC)\n\nWhen editing an LDC, the entire screen will be available for adding as many contacts, rungs and branches as permitted by the PiC. The LDC Modify mode function keys are as follows:\n\nCursor Keys\n\nIn the Modify mode, the cursor block highlights an entire element. The cursor keys (Up, Down, Left and Right Arrows) are used to move the cursor block around on the screen, one element at a time in the direction specified by the arrows.\n\nBackspace Key\n\nThe backspace key will delete individual characters within an element.\nModify coil/statement #100\n\nLDC To Be Modified\n\n<table>\n<thead>\n<tr>\n<th>Rung 1</th>\n<th>Rung 2</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>10</td>\n<td></td>\n</tr>\n<tr>\n<td>[-] [ ]</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nRung 4\nRung 5\nRung 6\nRung 7\nRung 8\n\nFunction Key Selection\n\n<table>\n<thead>\n<tr>\n<th>F1</th>\n<th>F2</th>\n<th>F3</th>\n<th>F4</th>\n<th>F5</th>\n<th>F6</th>\n<th>F7</th>\n<th>F8</th>\n<th>F9</th>\n<th>F10</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Clear Rung</td>\n<td>Clear Column</td>\n<td>Cmprs Rung</td>\n<td>Cmprs Column</td>\n<td>Expand Run</td>\n<td>Expand Column</td>\n<td>Horiz</td>\n<td>Copy Contact</td>\n<td>Help</td>\n<td>Done/Abort</td>\n</tr>\n</tbody>\n</table>\n\nFIGURE 3.9 MODIFY MODE SCREEN FORMAT\n\"Del\" Delete Key\n\nTo delete an entire element, position the cursor block over that element and press the \"Del\" key.\n\nBefore: Cursor Block positioned on rung to be cleared.\n\nFIGURE 3.10 CLEAR RUNG EXAMPLE\n\nF1 Clear Rung\n\nPressing this key will remove all of the elements in the horizontal rung containing the cursor block.\n\nAfter: Rung cleared.\n\nF2 Clear Column\n\nPressing this key will remove all of the elements in the vertical column containing the cursor block.\n\nBefore: Cursor Block positioned on column to be cleared.\nFIGURE 3.11 CLEAR COLUMN EXAMPLE\n\nF3 Compress Rung\n\nIf all the elements of a rung are cleared, placing the cursor block in this rung and pressing this key will delete the empty rung and move the rest of the LDC up one rung.\n\nBefore: Cursor Block positioned on rung to be compressed.\n\nAfter: Rung compressed.\n\nFIGURE 3.12 COMPRESS RUNG EXAMPLE\nF4 Compress Column\n\nIf all the elements of a column are cleared, placing the cursor block in this column and pressing this key will delete the empty column and move the rest of the LDC one column to the left.\n\nBefore: Cursor Block positioned on column to be compressed.\n\nAfter: Column compressed.\n\nFIGURE 3.13 COMPRESS COLUMN EXAMPLE\n\nF5 Expand Rung\n\nTo insert a new rung above an existing rung, position the cursor block on the existing rung and press this key. The existing rung and the rest of the LDC below it will drop down one rung leaving an empty rung for the entry of new elements.\n\nThis function will only work if there are no elements in the eighth rung.\n\nBefore: Cursor Block positioned on rung to be expanded.\nF6 Expand Column\n\nTo insert a new column to the left of an existing column, position the cursor block on the existing column and press this key.\n\nTo the right of it will move one column to the right leaving an empty column for the entry of new elements.\n\nThis function will only work if there are no elements in the seventh column.\n\nBefore: Cursor Block positioned on column to be expanded.\n\nAfter: Column expanded.\nF7 Horizontal Short\n\nThis key is used to insert a horizontal short in the LDC. The horizontal short key is a supplement to the standard LDC circuit symbol keys. It is used to fill in the gaps left by a deleted contact or branch and to extend a rung to the right for branching purposes.\n\n--- | (---\n\nBefore: Cursor Block positioned where Horizontal Short is to be positioned.\n\n--- | (---\n\nAfter: Horizontal Short inserted.\n\nFIGURE 3.16 INSERTING A HORIZONTAL SHORT\n\nF8 Copy Contact\n\nThis feature allows you to copy a contact and insert its duplicate anywhere in the LDC. To copy a contact, position the cursor block over the contact and press the F8 key.\n\nThe element will blink to acknowledge that the contact can now be duplicated. Position the cursor block to the desired location of the duplicate block and press this key again. If another element is already in this location, it will be replaced by the duplicate block.\n\nF9 Help\n\nPress this key for a brief description of the Modify function keys.\n\nF10 Done <Alt>\n\nTo exit the Modify mode and to execute any changes specified using the Modify process, press the F10 (Done) key.\n\nTo exit the Modify mode without executing any of these changes, press the \"Alt\" and the F10 (Abort) keys at the same time.\n\nNOTE\n\nThe GLLADD software will not accept an incorrect horizontal short entry. Incorrect entries include placing a short in the first (leftmost) column of an LDC or to the left of any contact on the same rung.\n\n--- | (---\n\nAfter: Horizontal Short inserted.\n\nFIGURE 3.16 INSERTING A HORIZONTAL SHORT\n\nF8 Copy Contact\n\nThis feature allows you to copy a contact and insert its duplicate anywhere in the LDC. To copy a contact, position the cursor block over the contact and press the F8 key.\n\nThe element will blink to acknowledge that the contact can now be duplicated. Position the cursor block to the desired location of the duplicate block and press this key again. If another element is already in this location, it will be replaced by the duplicate block.\n\nF9 Help\n\nPress this key for a brief description of the Modify function keys.\n\nF10 Done <Alt>\n\nTo exit the Modify mode and to execute any changes specified using the Modify process, press the F10 (Done) key.\n\nTo exit the Modify mode without executing any of these changes, press the \"Alt\" and the F10 (Abort) keys at the same time.\n\nAdditional Functions\n\nIn addition to the operations covered by the function keys, the Modify mode has the following additional functions.\n\n3.7.1.1 Inserting Elements Into An LDC\n\nTo insert an element in an LDC, use the cursor keys to position the cursor block in the desired column and row.\n\nTo insert a normally open contact, press the \"F\" key. Press the \"G\" key to insert a normally closed contact. Enter the number of the contact and press the return key.\n\nTo insert a horizontal short, position the cursor block to the desired location and press the F7 (Horiz. Short) function key.\n\nTo insert a branch, position the cursor block in the column directly to the left of the desired branch location and press the \"R\" key. Branches will appear in the far right side of the cursor block. The GLLADD software will not accept incorrect branching. Refer\nTo delete a branch, place the cursor block over the branch and press the \"R\" key.\n\nBefore: Cursor Block positioned over contact to left of desired branch position.\n\nAfter: Branch Inserted.\n\nFIGURE 3.17 BRANCH EXAMPLES\n\n3.7.1.2 Modifying Elements\nIn An LDC - To modify or replace an element in an LDC, position the cursor block over that element. Using the circuit symbol keys, enter the desired element.\n\nIf you entered a contact or coil, enter its number and press the return key. If the element is a timer coil, you will also have to enter the timer increment and another return.\n\nNOTE\nUnlike the Insert mode which uses a structured procedure for entering elements, the Modify mode allows you to move the cursor block from any location on a rung or column to any other location. This \"free form\" type of editing is designed to help you modify your ladder with as much flexibility and speed as possible.\n\nHowever, because this mode is not heavily structured, you will need to check your LDC for incorrect entries. The GLLADD software will not accept finished LDC's into the ladder diagram that do not conform with the proper PiC LDN format. However, you will be allowed to enter almost anything you want while you are in the process of editing.\n\n3.7.2 Modifying Statements\nBecause statements consist of only one line, editing them is much simpler. To edit a statement, enter the Modify mode and enter the statement number.\n\nThe cursor block will highlight an entire element that can be modified. Use the left and right arrow keys to move the cursor block forward or backwards through the statement. Pressing the \"Home\" key will return the cursor block to the beginning of the statement. Pressing the \"End\" key will advance the cursor block to the end of the statement.\n\nTo modify a highlighted element, simply type the correct element over it. If you press the wrong key at any time, use the backspace key to delete the incorrect character.\n\nYou can delete an optional qualifier contact by positioning the cursor block over the contact and pressing the F8 (Delete Contact) function key.\n\nIf you change the statement type, the remaining elements in the statement will be deleted so you can enter the specific information required by the statement.\n\nThe type of element highlighted by the cursor block depends upon the type of statement used. The following examples illustrate the different elements for each\ntype of statement. Each one of these elements can be modified independently of the others.\n\nLET Statement Example\n\n<table>\n<thead>\n<tr>\n<th>Statement Number</th>\n<th>Optional Qualifier Contact</th>\n<th>Statement Type</th>\n<th>Target Variable</th>\n<th>Target Variable Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2300</td>\n<td>IF (-1)/(1 - 1000)</td>\n<td>THEN LET V1</td>\n<td>V1</td>\n<td>V1 + 1</td>\n</tr>\n</tbody>\n</table>\n\nSET Statement Example\n\n<table>\n<thead>\n<tr>\n<th>Statement Number</th>\n<th>Optional Qualifier Contact</th>\n<th>Statement Type</th>\n<th>Target Coil</th>\n<th>Variable Number</th>\n<th>Comparison</th>\n<th>Variable Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2310</td>\n<td>IF (-1)/(1 - 1000)</td>\n<td>THEN SET 100</td>\n<td>:</td>\n<td>V10</td>\n<td><</td>\n<td>164</td>\n</tr>\n</tbody>\n</table>\n\nGOTO Statement Example\n\n<table>\n<thead>\n<tr>\n<th>Statement Number</th>\n<th>Optional Qualifier Contact</th>\n<th>Statement Type</th>\n<th>Target Statement Or Coil</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2320</td>\n<td>IF (-1)/(1 - 1000)</td>\n<td>THEN GOTO 2400</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nCALL Statement Example\n\n<table>\n<thead>\n<tr>\n<th>Statement Number</th>\n<th>Optional Qualifier Contact</th>\n<th>Statement Type</th>\n<th>Call Routine Name</th>\n<th>Call Routine Parameters</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2330</td>\n<td>IF (-1)/(1 - 1000)</td>\n<td>THEN CALL C111</td>\n<td>(4, 200, $8100)</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nFIGURE 3.18 STATEMENT ELEMENTS\n3.7.3 Exiting the Edit Mode\n\nTo leave the Edit mode and incorporate any changes that you have made, press the F10 (Done) key.\n\nIf you leave the Edit mode and want the computer to ignore any changes that you have made, press the \"Alt\" and F10 (Abort) keys at the same time.\n\n3.8 COPYING SECTIONS OF THE LDN\n\nAny series of consecutive blocks can be copied and inserted anywhere else in the LDN. This is especially useful if you want to create several complex sections that are almost identical to each other.\n\nFor example, if you want five identical devices to perform similar operations, you could type the same operation five times in the LDN. However, it is much easier to type in the operation only once and then duplicate it four times. After duplicating the operation, slight modifications can be made to eliminate duplicate coil and statement numbers and to account for different I/O points and module addresses etc.\n\n---\n\nBefore COPY operation\n\n---\n\nNote: Change coil or statement numbers to eliminate duplication of numbers.\n\nAfter COPY operation\n\n---\n\nFIGURE 3-19 COPY EXAMPLE\nTo enter the Copy mode from the GLLADD Ladder Editor/Compiler menu, press the F5 (Copy) function key. The computer will respond with the following message:\n\nEnter statement or coil numbers. 'B' for beginning, 'E' for end, (<Alt>F10) to abort.\n\nCOPY circuit(s), beginning with coil/statement #\nand ending with coil/statement #\n\nYou must decide which block or series of consecutive blocks you wish to copy.\n\nIf you want to copy one block only, use the same number followed by a return for the beginning and ending coil or statement number.\n\nTo copy a series of consecutive blocks, enter the coil or statement numbers for the first and last blocks in that series. Press the return key after entering each number.\n\nAfter the last return the computer will respond with the following message:\n\nCopy rung after coil/statement #\n\nYou must decide where the duplicated section of the LDN will be placed. To insert the section at the very beginning of the LDN, press the letter \"B\". To place the section at the very end of the LDN, press the letter \"E\".\n\nTo insert the duplicated section inside the LDN, enter the coil or statement number of a block located where you wish the section inserted. Press the return key. The duplicated section will then be inserted immediately after that block.\n\nIf you want to copy another section, follow the same procedure.\n\nTo exit the Copy mode without saving any of the duplicate blocks, press the \"Alt\" and F10 (Abort) keys at the same time.\n\nIMPORTANT\n\nCopying blocks will result in duplicate coil and statement numbers. Use the modify mode (see Section 3.7) to change the duplicate numbers to avoid problems with referencing coils and statements.\n\n3.9 MOVING SECTIONS OF THE LDN\n\nAny series of consecutive blocks can be moved and inserted anywhere else in the LDN. This will allow you to change the order of the blocks without retyping them.\n\nTo enter the Move mode from the GLLADD Ladder Editor/Compiler menu, press the F6 (Move) function key. The computer will respond with the following message:\n\nEnter statement or coil numbers. 'B' for beginning, 'E' for end, (<Alt>F10) to abort.\n\nMOVE circuit(s), beginning with coil/statement #\nand ending with coil/statement #\n\nYou must decide which block or series of consecutive blocks you wish to move.\n\nIf you want to move one block only, use the same number followed by a return for the beginning and ending coil or statement number.\n\nTo move a series of consecutive blocks, enter the coil or statement numbers for the first and last blocks in that series. Press the return key after entering each number.\n29...\n| 1[-----------------] 2[-----------------] 3[-----------------] 4[-----------------] 5[-----------------] 10\n|------------------( )--!\n\n30...\n| 11\n|------------------( )--!\n\n31...\n| 10[-----------------] 11[-----------------] 70\n|------------------( )--!\n\n32...\n| 2333 IF (-) [- 10] THEN LET V1 = V2 + 0\n\nBefore MOVE operation\n\n29...\n| 1[-----------------] 2[-----------------] 3[-----------------] 4[-----------------] 5[-----------------] 10\n|------------------( )--!\n\n30...\n| 10[-----------------] 11[-----------------] 70\n|------------------( )--!\n\n31...\n| 2333 IF (-) [- 10] THEN LET V1 = V2 + 0\n\n32...\n| 11\n|------------------( )--!\n\nAfter MOVE operation\n\nFIGURE 3-20 MOVE EXAMPLE\nAfter the last return the computer will respond with the following message:\n\nMOVE after coil/statement #\n\nYou must decide where the section of the LDN will be relocated. To insert the section at the very beginning of the LDN, press the letter \"B\". To place the section at the very end of the LDN, press the letter \"E\".\n\nTo insert the section inside the LDN, enter the coil or statement number of the block where you wish to insert the section and press the return key. The section will then be inserted immediately after that block.\n\nIf you want to move another section, follow the same procedure. To abort a move operation, leaving the blocks in their original position, press the \"Alt\" and the F10 keys at the same time.\n\n3.10 DELETING SECTIONS OF THE LDN\n\nAny block or series of consecutive blocks can be deleted from the LDN. This will allow you to rapidly remove sections of the LDN that are no longer needed.\n\nTo enter the Delete mode from the GLLADD Ladder Editor/Compiler menu, press the F7 (Delete) function key. The computer will respond with the following message:\n\nEnter statement or coil numbers. 'B' for beginning, 'E' for end, (<Alt>F10) to abort.\n\n*****************************************************************************\n\nDELETE circuit(s), beginning with coil/statement #\nand ending with coil/statement #\n\nYou must decide which block or series of consecutive blocks you wish to delete.\n\nIf you want to delete one block only, use the same number followed by a return for the beginning and ending coil or statement number.\n\nTo delete a series of consecutive blocks, enter the coil or statement numbers for the first and last blocks in that series. Press the return key after entering each number.\n\nIf you want to delete another section, follow the same procedure. Otherwise, to exit the Delete mode and return to the Ladder Editor/Compiler menu, press the F10 (Done) key.\n\nBefore DELETION\n\n29... 1 2 3 4 5 10\n\n30...\n\n31... 2333 IF (-) [- 10 ] THEN LET V1 = V2 + 0\n\nAfter DELETION\n\n29...\n\n30...\n\n2333 IF (-) [- 10 ] THEN LET V1 = V2 + 0\n\nFIGURE 3.21 DELETE EXAMPLE\n3.11 AUXILIARY FUNCTIONS\n\nIn addition to creating and editing ladder diagrams, the GLLADD Ladder Editor/Compiler also has a menu for auxiliary functions. These functions handle the remaining elements required for an LDN to function with a Pic.\n\nTo enter the Auxiliary Functions menu from the Ladder Editor/Compiler menu, press the F8 (Aux. Function) function key. A new menu will appear with the selections described below.\n\n3.11.1 Reinitialize\n\nWhen you first entered the GLLADD Ladder Editor/Compiler menu to create a new LDN, you were asked to enter the following information:\n\n1. The number of non-volatile variables.\n2. The number of retentive relays.\n3. The LDN size limit.\n4. The bank where the LDN resides.\n5. The highest bank used by the LDN (if you entered a \"1\" for item 4).\n\nIf you wish to change these numbers, you can use the Reinitialize function.\n\nPress the F1 (Reinitialize) function key. The computer will indicate what your previous choices were and will ask you to enter your new choices.\n\nIf you do not wish to change an entry, enter the same value that you used before. Otherwise, enter a new number.\n\nPress the return key after each entry. After the last entry is made, the Ladder Editor/Compiler menu will then return to the screen.\n\n3.11.2 Allocate Memory\n\nThis is the GLLADD equivalent to the Pic Allocate command. It is used to allocate the amount of memory reserved for Call Routines. To allocate this memory, press the F2 (Allocate Memory) key. The computer will respond with the following message:\n\nSubroutine area = (X), From ($XXXX) to ($YYYY). New Size =\n\nSelect an operation via the function keys.\n\nLadder Editor/Compiler Auxiliary Functions\n\n<table>\n<thead>\n<tr>\n<th>Function Key</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F1 Reinitialize</td>\n<td>Assigns the amount of memory available for call routines to be installed.</td>\n</tr>\n<tr>\n<td>F2 Allocate Memory</td>\n<td>Provides for inserting, renumbering, deleting and editing ladder messages.</td>\n</tr>\n<tr>\n<td>F3 Name</td>\n<td>Toggles the timer increment between 10 and 100 milliseconds.</td>\n</tr>\n<tr>\n<td>F4 Format</td>\n<td></td>\n</tr>\n<tr>\n<td>F5 Install Call Routines</td>\n<td></td>\n</tr>\n<tr>\n<td>F6 Change Timer Incr.</td>\n<td></td>\n</tr>\n<tr>\n<td>F7</td>\n<td></td>\n</tr>\n<tr>\n<td>F8</td>\n<td></td>\n</tr>\n<tr>\n<td>F9 Help</td>\n<td></td>\n</tr>\n<tr>\n<td>F10 <Alt> Abort</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nFIGURE 3-22 EDITOR/COMPILER AUXILIARY FUNCTIONS MENU\nThe \"X\" will indicate the actual number of bytes already allocated. The two hexadecimal numbers \"SXXXX\" and \"SYYYY\" indicate the actual memory locations reserved for Call Routines. To change the allocation, type in the number of bytes that you will need for Call Routine storage and press the return key.\n\nNOTE\n\nIf you are planning to install Call Routines from a diskette using the GLLADD software, there is no need to allocate memory using this function. The GLLADD Call Routine Installer will automatically allocate the correct amount of memory.\n\nHowever, the Allocate Memory function can also be used to determine how much memory GLLADD automatically allocates for Call Routines on diskette. Press the F2 (Allocate Memory) function key to display the amount of memory allocated. If you press the <Alt> <F10> Abort keys at the same time instead of entering a number, the number of bytes reserved for the Call Routines will remain unchanged.\n\n3.11.3 Name Ladder\n\nThis is an optional feature used to identify ladder diagrams. PiC ladder names created with this feature are independent of the ladder names used by the GLLADD systems for file handling purposes.\n\nAlthough recommended for the sake of consistency, the ladder name created here does not have to match the ladder name used by the GLLADD software. To name an LDN from the Auxiliary Functions menu, press the F3 (Name Ladder) function key. The following message will appear on the screen:\n\n```\nModify Ladder Name\nRUN PACK-09 1.0\nPush F10 when finished.\n```\n\nType in a name for the ladder to replace the line \"RUN PACK-09 1.0\" and press the F10 (Done) function key when finished. The Ladder Editor/Compiler menu will return to the screen.\n\n3.11.4 Message Formatter\n\nThe PiC is capable of displaying messages on a variety of devices. ASCII messages containing text are created, formatted and stored using either the GLLADD or the PiC Message Formatter.\n\nFor detailed information about the functions of the Message Formatter, refer to Section 7 in the PiC Family Programming Manual. For information about displaying the messages, refer to the Message Call Routine documentation supplied with the PiC Part One Standard Call Routines.\n\nTo enter the GLLADD Message Compiler menu press the F4 (Format Messages) function key. Another menu will be displayed.\n\nTo leave the GLLADD Message Compiler menu press the F10 (Done) key. If you want to leave the Message Compiler menu but ignore any changes you may have made, press the \"Alt\" and the F10 keys (Abort) at the same time.\n\n3.11.4.1 Creating New Messages - To create a new message, press the F2 (Insert) function key. The computer will display the following message:\n\n```\nInsert message #\n```\n\nEnter the message identification number and press the return key. This can be any integer from 0 through 255 as long as the number has not be reserved for another message.\nMessage Formatter\n\nDisplay a single ladder message, or portions of the entire table.\n\nDeletes an entry in the ladder message table.\n\nProvides format constants for the CRT, from popular formats or enter your own.\n\n<table>\n<thead>\n<tr>\n<th>F1</th>\n<th>Display</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F2</td>\n<td>Insert</td>\n</tr>\n<tr>\n<td>F3</td>\n<td>Delete</td>\n</tr>\n<tr>\n<td>F4</td>\n<td>Renumbe</td>\n</tr>\n<tr>\n<td>F5</td>\n<td>Format</td>\n</tr>\n<tr>\n<td>F6</td>\n<td>Edit</td>\n</tr>\n<tr>\n<td>F7</td>\n<td></td>\n</tr>\n<tr>\n<td>F8</td>\n<td></td>\n</tr>\n<tr>\n<td>F9</td>\n<td>Help</td>\n</tr>\n<tr>\n<td>F10</td>\n<td><Alt></td>\n</tr>\n<tr>\n<td></td>\n<td>Abort</td>\n</tr>\n</tbody>\n</table>\n\nInserts a new entry into the ladder message table.\n\nChanges the number of an existing entry in the ladder message table.\n\nModifies an existing entry in the ladder message table.\n\nSelect an operation via the function keys.\n\nFIGURE 3-23 MESSAGE FORMATTER MENU\n\nThe next message the computer will display is:\n\nEnter the new message, CTRL-X to enable hex entry. <F10> when done, <Alt> <F10> to abort.\n\nType in the desired message. Messages may contain up to 254 characters including spaces and returns. Incorrect entries can be deleted by pressing the backspace key. Press the F10 (Done) function key when finished. The computer will ask:\n\nEnter this message (Y/N)?\n\nPress the \"Y\" (yes) key to enter the message. If you don't want the message, press the \"N\" (no) key. After either entry, the computer will ask for the next message.\n\nTo create a message consisting of hexadecimal characters, press the \"Ctrl\" and the \"X\" keys at the same time before entering the message itself. The prompt \"s\" will appear indicating that the next entry will be a hexadecimal number. After typing in the first two digits, the prompt \"$\" will appear again waiting for the entry of two more hex characters. This will continue until the F10 key or \"Alt\" and F10 keys are pressed or if the message exceeds 254 characters.\n\nAfter entering the last message, press the F10 (Done) key to exit the Insert mode. To exit the Insert mode without saving the message, press the \"Alt\" and the F10 keys (Abort) at the same time.\n\n3.11.4.2 Displaying Messages - After messages have been created, they can be viewed by pressing the F1 (Display) function key. After pressing this key the computer will display the following line:\n\nDisplay starting at message #\n\nEnter the identification number of the first message you want to view and press the return key. The message will appear on the screen with its identification number to the left.\nEach time the space bar is pressed, the next message will be displayed until no more messages remain. Pressing the number \"0\" will display all of the remaining messages on the screen. The computer will also identify any unused message numbers that fall between the numbers of existing messages. To return to the Message Compiler Menu, press the F10 (Done) key.\n\n3.11.4.3 Deleting A Message - To delete a message, press the F3 (Delete) function key. The computer will respond with:\n\nDelete message #\n\nEnter the identification number of the message and press the return key. The computer will display the message and as the following question:\n\nDelete this message (Y/N)?\n\nPress the \"Y\" (yes) key to delete the message. Otherwise, press the \"N\" (no) key. The computer will then ask for the number of another message to delete. Enter the number of another message followed by a return or press the F10 (Done) function key to return to the Message Formatter Menu.\n\n3.11.4.4 Renumbering Messages - This function allows you to change the identification number of any message. A message number can be changed to any number from 0 to 255 if the new number is not being used by another message.\n\nPress the F4 (Renumber) function key to renumber a message. The computer will respond with:\n\nRenumber message #\n\nEnter the existing identification number for the message you wish to renumber and press the return key. The computer will display the message and ask you to enter the new message number. Enter the new number and a return. Press the F10 (Done) key to return to the Message Compiler menu.\n\n3.11.4.5 Editing Messages - To change the contents of a message, press the F6 (Edit) function key. The computer will respond with:\n\nEdit message #\n\nEnter the identification number of the message you wish to edit followed by a return.\n\nIf you are editing a standard ASCII message, the message will be displayed on the screen with the cursor on the first character of the message. Use the arrow keys to move the cursor throughout the message.\n\nTo insert characters, position the cursor in the desired location and type the characters in. Any characters on or after the cursor will move over to make room for the new characters.\n\nPress the \"Del\" key to delete the character at the cursor position. Press the backspace key to delete a character to the left of the cursor.\n\nPress the \"Home\" key to move the cursor to the beginning of the line. Press the \"End\" key to move the cursor to the end of the line.\n\nAfter editing the message, press the F10 (done) function key. If you decide not to incorporate any changes you may have made, press the <Alt> <F10> (abort) function keys at the same time.\n\nIf you are editing a message consisting of hexadecimal characters, the message will be displayed on the screen along with the following:\n\nEnter the new message,\nCTRL-X to enable hex entry,\n<F10> when done,\n<Alt> <F10> to abort.\n\nPress the \"Ctrl\" and the \"X\" keys at the same time. The prompt \"S\" appear indicating that the next entry will be a hexadecimal number. Type in a new hexadecimal or ASCII message.\nAfter entering the new message, press the F10 (Done) function key. If you decide not to change the original message, press the \"Alt\" and the F10 keys (Abort) at the same time. The Message Compiler menu will reappear on the screen.\n\n3.11.4.6 Configuring The CRT - This function only applies if you are going to display messages on a video monitor (CRT) using the G&L video modules. It allows you to determine the number of horizontal rows and the number of characters per row that will be displayed on a video monitor. To configure the display, press the F5 (Format) function key. The computer will display a small menu on the screen.\n\nCRT CONFIGURED 32 X 16\n\nCONFIGURE CRT\n\n0. User Defined Constants\n1. Standard Configuration 1 (32 x 16)\n2. Standard Configuration 2 (40 x 18)\n3. Standard Configuration 3 (64 x 16)\n\nEnter number corresponding to choice\n(<Alt> <F10> to abort)\n\nFIGURE 3-24 CRT CONFIGURATION MENU\n\nSelect the desired format from the menu. Selection one is a standard configuration that has 16 rows with 32 characters per row. If no selection is made, the system will default to this format. Selection two has 18 rows with 40 characters per row and selection three has 16 rows with 64 characters per row.\n\nSelection zero allows you to configure the CRT to a nonstandard format. If you press the number \"0\", the following message will be displayed on the screen:\n\nEnter 17 bytes of hex CRT configuration data! $\n\nLadder Editor/Compiler\n\nType in the hexadecimal codes for the desired configuration as listed in Section 7 of the PiC409 Family Programming Manual (Table 7-1). The configuration you use is limited by the type of crystal on the video interface module. The standard crystal supplied with this module is a 12.576 MHz crystal.\n\nAfter entering the correct string of hexadecimal codes press the F10 (Done) key. If you decide not to change the configuration after entering the hexadecimal codes, press the \"Alt\" and F10 keys (Abort) at the same time.\n\n3.11.5 Installing Call Routines\n\nThis function allows the programmer to copy and install Call Routines into the LDN. The Call Routines can be supplied from G&L on disk or they can reside on a Call Routine EPROM (Erasable Programmable Read Only Memory) module resident in the PiC.\n\nIf you are installing Call Routines from disk, read Section 3.11.5.1 before proceeding.\n\nIf you are installing Call Routines from a Call Routine EPROM module, read Section 3.11.5.2.\n\nNOTE\n\nIf you are installing Call Routines from a cassette or cartridge tape, you cannot use this function. Refer to Section 9 in the PiC409 Family Programming Manual for instructions regarding Call Routines supplied on tape.\n\n3.11.5.1 Installing Call Routines From Disk - Press the F6 (Install Call Routines) function key from the GLLADD Ladder Editor/Compiler Auxiliary Functions menu. The computer will display the following message:\n2. If you choose to select each call individually, press the letter \"I\" instead of the letter \"S\". The computer will respond with the following message:\n\nEnter the name of the Call routine you wish installed.\n\nAfter entering the name of the Call Routine, press the return key. The computer will reply with the following:\n\nIs this Call routine located in EPROM (Y/N)?\n\nPress the letter \"N\" (no). The computer will copy the Call routine and then repeat the procedure to allow you to enter more Call Routines. After the last Call Routine is installed, press the F10 (Done) function key. The computer will instruct you to return the system (GLLADD) disk to the system drive. After doing so, press any key to return to the Ladder Editor/Compiler menu.\n\nNOTE\n\nIf insufficient memory space is allocated for Call Routines, the GLLADD software will automatically allocate the correct amount.\n\nAfter specifying which Call Routines to install, including C912 Real Time Debug (Section 3.11.5.3), enter the PiC Call Routine Installer from the PiC AUX 2 mode and use the REINSTALL function as described in Section 3.11.5.4. This is the operation that actually installs the Call Routines in the PiC.\n\n3.11.5.2 Installing Call Routines From EPROM - Press the F6 (Install Call Routines) function key from the GLLADD Ladder Editor/Compiler Auxiliary Functions menu. The computer will display the following message:\nGLLADD will search the current directory on the system disk, and any directories indicated by PATH for the Call Routines. If the Call Routines are not on your system disk and are not in the PATH directory, remove the system disk and insert the Call Routine disk into the system drive.\n\nPush any key when ready to continue.\n\n---\n\n**NOTE**\n\nIf you are installing Call Routines from the G&L Call Routine EPROM module, there is no need to switch any disks in the system drive. However, if you do not have Call Routines in the system drive, you will have to enter the number of parameters required for each Call Routine manually.\n\nIf you do not know the number of parameters required or do not wish to enter them manually, put the Call Routine disk in the system drive if Call Routines are not there already.\n\nPress any key to continue. The computer will respond with the following message:\n\nDo you wish to scan the Call disk or enter the Call names individually (S/I)?\n\nPress the letter \"I\". The computer will respond with the following message:\n\nEnter the name of the Call Routine you wish installed.\n\nAfter entering the name of the Call Routine, press the return key. The computer will reply with the following:\n\nIs this Call routine located in EPROM (Y/N)?\n\nPress the letter \"Y\" (yes).\n\n---\n\nIf you have Call Routines in the system drive, the computer will install the Call Routine and request the name of the next one.\n\nIf you do not have Call Routines in the system drive, the computer will respond with the following statement:\n\nWarning! Unable to determine the correct directory for the GLLADD Call Routines.\n\nEnter the number of parameters required.\n\nEnter the correct number of parameters and press the return key. The computer will install the Call Routine and then repeat the procedure to allow you to enter more Call Routines. If you are unsure of the exact number of parameters, refer to the documentation supplied with the Call Routines or insert a Call Routine disk in the system drive.\n\nAfter the last Call Routine is installed, press the F10 (Done) function key. The computer will instruct you to return the system (GLLADD) disk to the system drive. Return the system disk to this drive if it is not there already and press any key to return to the Ladder Editor/Compiler menu.\n\nAfter specifying which Call Routines to install from EPROM, including Real Time Debug (C912) (Section 3.11.5.3), enter the PiC Call Routine Installer from the PiC AUX 2 mode and use the REINSTALL function as described in Section 3.11.5.4. This is the operation that actually installs the Calls in the PiC.\n\n---\n\n**NOTE**\n\nThe Call Routine EPROM module must be in your PiC main nest before Call Routines can be installed. The only exception is Real Time Debug (C912) which is already resident in the PiC Compiler module.\n3.11.5.3 Installing Real Time Debug\nDebug (C912) - The Real Time Debug Call Routine C912I Routine is located on EPROM in all G&L PiC's. Follow the instructions for installing Call Routines from EPROM in Section 3.11.5.2. Note: C912 has only one parameter.\n\n3.11.5.4 Reinstalling Call Routines\nAfter loading the PiC with an LDN created using the GLLADD Ladder Editor/Compiler, a simple operation called \"Reinstall\" must be performed. This allows the PiC to accurately access the Call Routines from user memory or EPROM.\n\n1. If you are using the AUX 1 Mode: Connect the computer to the Terminal port on the PiC control panel. Set the MODE switch on the control panel to the AUX 1 position and press the initialize button.\n\n Select the AUX 1 Support mode from the Main Menu. From the AUX 1 menu, enter the AUX 2 mode. When the AUX 2 menu appears, select the Call Routine Installer. When the prompt \"*\" appears, press the \"R\" key for REINSTALL. The PiC will then install the Call Routines that you specified in the Ladder Editor/Compiler.\n\n2. If you are not using the AUX 1 mode: Enter the Terminal mode as described in Section 8 - GLLADD AUXILIARY FUNCTIONS. Connect the computer to the Terminal port on the PiC control panel. Set the MODE switch on the PiC Control Panel to the AUX 2 position and press the initialize button.\n\n When the AUX 2 menu appears, select the Call Routine Installer.\n\nWhen the prompt \"*\" appears, press the \"R\" key for REINSTALL. The PiC will then install the Call Routines that you specified in the Ladder Editor/Compiler.\n\n3.11.6 Changing The Timer Increment\nTo switch the timer increment for time delay to energize (TE) and time delay to de-energize (TD) coils, press the F6 (Change Timer Incr.) function key from the Ladder Editor/Compiler Auxiliary Functions menu. The computer will indicate which timer increment (10 milliseconds or 100 milliseconds) you switched into. All timer coils in the LDN will now use this increment unless it is changed back to the alternate increment.\n\n3.12 EXITING THE GLLADD LADDER EDITOR/COMPILER\nTo exit the GLLADD Ladder Editor/Compiler menu, press the F10 (Done) function key. This will save any changes you may have made while in the Ladder Editor/Compiler and return you to the Main menu.\n\nIf you press the <Alt> <F10> Abort function keys at the same time, the following message will appear:\n\nOperation aborted, ignore any changes (y,n)?\n\nIf you press \"y\" (yes), the software will not save any changes that you may have made in the Ladder Editor/Compiler and will return you to the Main Menu.\n\nIf you press \"n\" (no), the software will save any changes you may have made and return you to the Main Menu.\nSECTION 4 - LADDER DOCUMENTER\n\nThe primary function of the GLLADD software is the development and documentation of LDNs. When used for documentation, the software allows the user to assign meaningful labels to contacts, coils and variables, and provides for nearly unlimited commenting on an LDN printout.\n\nFIGURE 4.1 SAMPLE DOCUMENTED LDN\n4.1 DEFINITION FILES\n\nThe text required for documenting an LDN is stored in a separate file called a definition file. A definition file uses the same ladder name as the LDN file. However, the three letter extension is \".DEF\" instead of \".LDN.\" Under most circumstances, you will only have to refer to the definition file by its ladder name and not by its extension.\n\nTo create or modify a definition file, return to the main menu and press the F2 key labeled \"Edit Documen. Database.\" The computer will ask for a ladder name. Enter the name of the LDN you wish to document and press the return key.\n\nThe Documentation Database Menu will appear on the screen.\n\n4.2 ADDING AND MODIFYING TEXT\n\nPress the F1 key in the Documentation Database Editor menu to begin the actual documentation. The Add or Modify menu will appear on the screen. This menu is used to create and modify the text for headings, labels and comments etc.\n\nPress the function key associated with the desired item from the menu. If you specify a contact label, the computer will ask for a contact number. If you specify a variable label, the computer will ask if you are using a PC400 controller or a Pic 409 controller. After indicating the correct controller followed by a return, the computer will then ask for a variable number.\n\nIf you specified a heading, comment or top of page, the computer will ask you for a coil or statement number. Enter the appropriate number followed by a return.\n\nDocumentation Database Editor\n\n<table>\n<thead>\n<tr>\n<th>Add F1 or Modify</th>\n<th>F2 Delete</th>\n<th>Delete an entry in the documentation database.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F3 Copy</td>\n<td>F4 Move</td>\n<td>Move an existing entry in the documentation database.</td>\n</tr>\n<tr>\n<td></td>\n<td>F5</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>F6</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>F7</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>F8</td>\n<td></td>\n</tr>\n<tr>\n<td>F9 Help</td>\n<td>Done <Alt> Abort</td>\n<td>Select an operation via the function keys.</td>\n</tr>\n</tbody>\n</table>\n\nFIGURE 4.2 DOCUMENTATION DATABASE EDITOR MENU\nContact labels appear over all contact and coil references of a device.\n\nComments can appear above, below or to the right of a coil or statement.\n\nTop-of-page causes a top of form before a specified coil or statement.\n\n<table>\n<thead>\n<tr>\n<th>Contact Label</th>\n<th>Variable Label</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F1</td>\n<td>F2</td>\n</tr>\n<tr>\n<td>F3 Comment</td>\n<td>F4 Heading</td>\n</tr>\n<tr>\n<td>F5 Top of Page</td>\n<td>F6</td>\n</tr>\n<tr>\n<td>F7</td>\n<td>F8</td>\n</tr>\n<tr>\n<td>F9 Help</td>\n<td>Done</td>\n</tr>\n<tr>\n<td></td>\n<td>Abort</td>\n</tr>\n</tbody>\n</table>\n\nVariable labels appear over all LET/SET statement references of a variable.\n\nHeadings print on each page beginning with a specified coil or statement.\n\nSelect an operation via the function keys.\n\n**FIGURE 4.3 ADD OR MODIFY MENU**\n\nBefore: Contact 100 has no label. Contact 200 is incorrectly labeled.\n\nAfter: Label for contact 100 is added. Label for contact 200 is corrected.\n\n**NOTE:** This example required two ADD/MODIFY operations. The first operation was for contact 100. The second operation was for contact 200.\n\n**FIGURE 4.4 ADD OR MODIFY EXAMPLE**\n\nWhen you specify a comment number, the computer will ask if you want the comment to appear before (B), after (A) or to the right (R) of the comment. Press the letter corresponding to your choice.\n\nExcept for the Top of Page function which requires no text, a text field will appear on the screen.\n\nType in the desired text to fill the field. If the text exceeds the maximum line width, a warning will sound and the computer will not accept any more characters on that line. When typing labels or comments, use the return key to advance to the next line.\n\nThe cursor can be controlled by the arrow keys on the numeric keypad for easy editing of the text. Press the...\n\"Del\" key to delete the character at the cursor position. Press the backspace key to delete the character to the left of the cursor.\n\nTo insert characters or spaces between parts of the text, position the cursor where the new characters will go and type them in.\n\nAfter entering and editing the text, several options are available.\n\n1. To save your entry and add another one, press the F6 (increment) key until the number of the next contact, variable, coil or statement number you want appears on the screen.\n\n2. To save your entry and edit a previous entry, press the F5 (decrement) key until the desired element or block appears on the screen.\n\n3. To save your entry and return to the Add or Modify Menu press the F10 (done) key.\n\n4. To return to the Add or Modify Menu without saving your entry, press the \"ALT\" and F10 (abort) keys at the same time.\n\nThe different entries that can be made in the Add or Modify Mode are as follows:\n\n4.2.1 Contact Labels\n\nContact labels are used to identify, in words, what a contact or coil actually is. These labels consist of three lines of text with a maximum number of nine characters per line. Each label identifies a particular control relay or I/O address and will be displayed above that item wherever it appears in the documented LDN.\n\nTo create a contact label from the Add or Modify Menu, press the F1 \"Contact Label\" function key. The computer will ask for the contact number. Enter the number and press the return key.\n\nThe screen will then display the contact with an entry field above it. Type the desired information into this field and select one of the four options listed at the end of Section 4.2.\n\nContact labels may contain three lines with nine characters per line.\n\nOne shot contact for LDN.\n\n22\n\n[---] [---]\n\nFIGURE 4.5 CONTACT LABEL EXAMPLE\n\n4.2.2 Variable Labels\n\nVariable labels, like contact labels, consist of up to three lines of nine characters each. Each variable label is assigned to a specific variable number. Once this label is assigned, it will be displayed above that variable wherever it appears in a LET or SET statement in the documented LDN.\n\nTo create a variable label from the Add or Modify Menu, press the F2 \"Variable Label\" function key. The computer will ask for the variable number.\n\nEnter the number, correct number and press the return key. There is no need to begin a PiC409 or PiC49 variable number with the letter \"V\".\n\nThe screen will then display the variable with an entry field above it. Type the desired information into this field and select one of the four options listed at the end of Section 4.2.\n\nVariable labels may contain three lines with nine characters per line.\n\nSet auto-increment\n\nV1\n\nFIGURE 4.6 VARIABLE LABEL EXAMPLE\n\nLadder Documenter\nWhen creating the first variable label in a definition file, the software will ask you to specify if you are using a PC400 or a PiC409. After indicating which control you are using, press the return key.\n\nThis sets up the file to accept only those variable numbers designated for that controller. The PC400 uses 260 variable numbers from A0 through Z9. The PiC409 and PiC49 use variable numbers 0 through 899.\n\n4.2.3 Comments\n\nComments provide additional information about particular coils or LDN statements. The size of a comment is limited only by the amount of memory and available disk space. Comments may appear before, after or to the right of a particular coil or LDN statement.\n\nComments that appear before or after a block may be up to 86 characters in length. Comments that appear to the right of a block may contain as many as 50 characters.\n\nThe exact number of characters per line depends upon the page width specified in the initialization procedure (Section 2.2). Wider pages allow more characters for these comments.\n\n---\n\nThis ladder rung sets coil #1000 which is the one-shot for C113 and most of the message displays.\n\n<EOB>\n\nFIGURE 4.7 COMMENT EXAMPLE\n4.2.4 Headings\n\nHeadings are single lines of text printed at the top of each page beginning with a specified LDN block. Headings are typically used to identify different sections of an LDN.\n\nThe maximum heading length is 78 characters. However, the actual length depends upon the page width specified in the initialization process. Wider pages allow more characters per heading.\n\nWhen a heading is first used, the GLLLADD software forces a form feed to the printer so the heading and its corresponding block number will appear at the top of the next page.\n\nThis heading will then appear at the top of all succeeding pages until it is replaced by another heading.\n\nTo create a heading, press the F4 \"Heading\" function key from the Add or Modify Menu. Enter the block number associated with the heading and press the return key.\n\nA field will appear on the screen where one line of text can be entered. After entering the heading, select one of the four options listed at the end of Section 4.2.\n\n---\n\nFIGURE 4.8 HEADING EXAMPLE\n\n4.2.5 Top of Page\n\nThis function does not add any text to the document. Instead it commands a form feed before a specified coil or statement so that block will appear at the top of the next page when the documented LDN is printed.\n\nTo use this function, press the F6 (Top of Page) function key from the Add or Modify Menu. After assigning this function to a specific block, the Add or Modify menu will return to the screen.\n\n4.3 DELETING TEXT\n\nTo delete a block of text or a top of page command from the definition file, press the F2 (delete) function key from the Documentation Database Editor menu. The Delete menu will appear.\n\nSelect the appropriate function key to delete a contact label, variable label, heading, comment or top of page command.\n\nDepending on the function key used, the software will ask for the number of a contact, variable or statement or coil. Enter the number and press the return key to complete the operation. The text associated with that number will be deleted from the file and the Documentation Database Editor menu will reappear on the screen.\nDelete\n\nContact labels appear over all contact and coil references of a device.\n\nComments can appear above, below or to the right of a coil or statement.\n\nTop-of-page causes a top of form before a specified coil or statement.\n\n<table>\n<thead>\n<tr>\n<th>Contact F1 Label</th>\n<th>Variable F2 Label</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F3 Comment</td>\n<td>F4 Heading</td>\n</tr>\n<tr>\n<td>F5 Top of Page</td>\n<td>F6</td>\n</tr>\n<tr>\n<td>F7</td>\n<td>F8</td>\n</tr>\n<tr>\n<td>F9 Help</td>\n<td>F10 <Alt> Done</td>\n</tr>\n<tr>\n<td></td>\n<td>F10 Abort</td>\n</tr>\n</tbody>\n</table>\n\nVariable labels appear over all LET/SET statement references of a variable.\n\nHeadings print on each page beginning with a specified coil or statement.\n\nSelect an operation via the function keys.\n\n**FIGURE 4.9 DELETE MENU**\n\n```\nMotor\nOn\nSwitch\n2000\n---] [---\n```\n\n```\nMotor\n2002\n-( )--!\n```\n\n```\nMotor\nOn\nLight\n2001\n---] [---\n```\n\n```\nMotor\n2001\n-( )--!\n```\n\nBefore: Label for Contact 2000 is printed wherever 2000 appears.\n\n```\n2000\n---] [---\n```\n\n```\nMotor\n2002\n-( )--!\n```\n\n```\nMotor\nOn\nLight\n2001\n---] [---\n```\n\n```\nMotor\n2001\n-( )--!\n```\n\nAfter: Label for contact 2000 does not appear in the printed LDN.\n\n**FIGURE 4.10 DELETE EXAMPLE**\n4.4 COPYING TEXT\n\nThe text used for one contact, variable, coil or statement number may be copied for use with one or more other numbers.\n\nFor example: The label for contact number 2003 may read ON/OFF/SWITCH. To use the same label for contacts 2004, 2005 and 2006, enter the Copy mode by pressing the F3 (copy) function key from the Documentation Database Editor menu. Another menu will appear on the screen.\n\nPress the F1 key titled Contact Label. The software will request a contact number. Enter 2003 and press the return key.\n\nThe software will then ask for the contact number that will receive the copied text. Enter 2004 and press the return to complete the operation.\n\nThe Documentation Database Editor menu will return to the screen. Repeat the procedure two more times using contacts 2005 and 2006 in place of 2004. All four contacts should now have the same label.\n\n<table>\n<thead>\n<tr>\n<th>Copy</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Variable labels appear over all LET/SET statement references of a variable.</td>\n</tr>\n<tr>\n<td>Headings print on each page beginning with a specified coil or statement.</td>\n</tr>\n</tbody>\n</table>\n\nContact labels appear over all contact and coil references of a device.\n\nComments can appear above, below or to the right of a coil or statement.\n\n<table>\n<thead>\n<tr>\n<th>F1 Label</th>\n<th>F2 Label</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F3 Comment</td>\n<td>F4 Heading</td>\n</tr>\n<tr>\n<td>F5</td>\n<td>F6</td>\n</tr>\n<tr>\n<td>F7</td>\n<td>F8</td>\n</tr>\n<tr>\n<td>F9 Help</td>\n<td>Done <Alt> Abort</td>\n</tr>\n</tbody>\n</table>\n\nSelect an operation via the function keys.\n\nFIGURE 4.11 COPY MENU\n4.5 MOVING TEXT\n\nText can be easily transferred from one contact, variable or coil or statement number to another by using the F4 (move) function key from the Documentation Database Editor menu.\n\n<table>\n<thead>\n<tr>\n<th>F1 Label</th>\n<th>Contact</th>\n<th>F2 Label</th>\n<th>Variable</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F3 Comment</td>\n<td>F4 Heading</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>F5 Top of Page</td>\n<td>F6</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>F7</td>\n<td>F8</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>F9 Help</td>\n<td>Done F10 <Alt> Abort</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nSelect an operation via the function keys.\n\nFIGURE 4.13 MOVE MENU\nFor example: A comment used for statement 2300 can be transferred to statement 2500. Once the comment is moved, it will be printed with statement 2500 and statement 2300 will no longer be printed with a comment.\n\nTo move the text, press the F4 (move) function key and wait for the Move menu to appear.\n\nSelect the appropriate key to move a contact label, variable label, heading, comment or top of page. The software will request the number of the contact, variable, coil or statement associated with the text to be moved. Enter the number and press the return key.\n\nThe software will then request the number of the contact, variable, statement or coil that will receive the text. After entering this number, press the return key. This completes the operation and the Documentation Database Editor menu will return to the screen.\n\n---\n\nThis ladder rung has only one contact.\n\n2000\n----] [---------------------------( )--!\n\n2030\n----] [---------------------------( )--!\n\nBefore: Comment appears above block 2030.\n\n2000\n----] [---------------------------( )--!\n\nThis ladder rung has only one contact.\n\n2030\n----] [---------------------------( )--!\n\n2050\n----] [---------------------------( )--!\n\nAfter: Comment appears above block 2050.\n\n---\n\nFIGURE 4.14 MOVE EXAMPLE\nSECTION 5 - LISTING A DOCUMENTED LDN\n\nAfter all of the headings, comments and labels are entered and edited, the documented LDN may be listed on a printer or on a disk file.\n\nNOTE\n\nThe initialization procedure determines whether your listing will be on a printer or a disk. To change the type of device used for listing documented ladders, refer to Section 2.2.2 - Changing The Initialization Parameters.\n\nReturn to the Main Menu and press the F3 (List Documented Ladder) function key. Enter the ladder name of the LDN to be listed and press the return key.\n\nThe computer will provide you with several options for your listing. These options are as follows:\n\n1. Ladder Listing. If you want to list the documented LDN, select this option.\n\n2. Full or Partial Ladder Listing. If you selected the first option, you will be asked if you want to list the full LDN or a portion of it. If you want the full ladder listing, press the return key.\n\n If you only want a portion of the LDN, indicate the coil or statement number of the first and last blocks that you want included in the listing. Separate the first and last blocks with a hyphen. For example, to list the blocks from coil 100 through statement 2300, enter: \"100-2300\".\n\n3. Cross Reference Listing. If you want your listing to include cross reference tables, select this option.\n\n This information will then be printed whether you selected a ladder listing or not.\n\nAfter the listing is complete, the Main Menu will return to the screen.\n\n5.1 CROSS REFERENCE INFORMATION\n\nIn addition to its labeling capabilities, GLLADD also provides automatic cross referencing both in and at the end of the documented LDN. The user can quickly locate contacts, coils, variables and statements by referring to the block numbers provided in the cross reference tables. Block numbers are found in numerical order on the left side of each LDC or statement in the documented LDN.\n\n5.1.1 Contact Cross References\nIn The LDN\n\nGLLADD will let you know where a contact number is controlled by a coil or where it is controlled by a SET statement. The block number of the coil or SET statement will be printed below the contact wherever it appears as a normally open or normally closed contact. In addition to the block number, the software also provides additional information as indicated in the following illustration.\nFIGURE 5.1 EXAMPLE CONTACT CROSS REFERENCES WITHIN THE LDN\n\n5.1.2 Coil Cross References In The LDN\n\nWhen a line width of 100 or more characters is specified during the initialization procedure, additional cross reference information is listed to the right of the coil numbers. This information contains the block numbers where the coil appears as a contact in the LDN. The blocks are identified as shown below:\n\nBlock number where coil appears as a normally open contact in an LDC or SET statement.\n\nBlock number where coil appears as a normally closed contact in an LDC or SET statement.\n\nBlock number where coil appears as a CALL statement parameter.\n5.1.3 Cross References At The End Of The LDN\n\nCross Reference Listings provide four different tables of information. The four different tables are:\n\n1. messages\n2. contacts\n3. variables\n4. statements.\n\nMessages - If messages are included in the LDN, GLLADD will list all of the message numbers in numerical order, beginning with the first message used and ending with the last message used. GLLADD also lists the actual message to the right of the message number. If no message was created for a particular number, GLLADD will print \"??????\". If the message was formatted in hexadecimal, the message number will be listed with an \"H\" attached to it and the message itself will be listed as a string of hexadecimal numbers, each preceded by a \"$\".\n\nContacts - GLLADD lists all the contact numbers used in an LDN. This listing is in numerical order and contains several columns of information as shown below:\n\n<table>\n<thead>\n<tr>\n<th>Contact Number</th>\n<th>Contact Label</th>\n<th>Number Of The Block Controlling Contact</th>\n<th>Blocks Where Contact Is Used in the LDN.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>Set 1st \\ Cursor \\ position. \\</td>\n<td>S 46</td>\n<td>#21,34,35</td>\n</tr>\n<tr>\n<td>2</td>\n<td>Set 2nd \\ cursor \\ position. \\</td>\n<td>S 47</td>\n<td>36,37</td>\n</tr>\n<tr>\n<td>3</td>\n<td>Set 3rd \\ cursor \\ position. \\</td>\n<td>S 48</td>\n<td>38,39</td>\n</tr>\n<tr>\n<td>4</td>\n<td>Set 4th \\ cursor \\ position. \\</td>\n<td>S 49</td>\n<td>40,41</td>\n</tr>\n<tr>\n<td>5</td>\n<td>Set 5th \\ cursor \\ position. \\</td>\n<td>S 50</td>\n<td>11,15,42,43</td>\n</tr>\n<tr>\n<td>6</td>\n<td>Clear \\ variables \\ on screen</td>\n<td>S 54</td>\n<td>16,17,18,19,20,44,45,52</td>\n</tr>\n<tr>\n<td>10</td>\n<td>Increment value of \\ V1. \\ C</td>\n<td>51</td>\n<td>9,13,51,53</td>\n</tr>\n<tr>\n<td>11</td>\n<td>Change \\ values \\ of \\ V2, V3, V4. \\ C</td>\n<td>53</td>\n<td>33,34,30,33</td>\n</tr>\n<tr>\n<td>15</td>\n<td>Reset V2 \\ to \\ -1000. \\ S 25</td>\n<td>26</td>\n<td></td>\n</tr>\n<tr>\n<td>16</td>\n<td>Reset V4 \\ to \\ SA077. \\ S 31</td>\n<td>32</td>\n<td></td>\n</tr>\n<tr>\n<td>999</td>\n<td>Set \\ One-shot \\ coil.1000. \\</td>\n<td>S 55</td>\n<td>/55</td>\n</tr>\n<tr>\n<td>1000</td>\n<td>One-shot \\ contact \\ for LDN. \\ C</td>\n<td>55</td>\n<td>/1,3,4,5,6,7,8,10,12,14,29</td>\n</tr>\n</tbody>\n</table>\n\nFIGURE 5.4 CONTACT CROSS REFERENCES\n\nListing A Documented LDN\nVariables - The variable list is similar to the contact list. However, the source column is not used because it does not apply to variables.\n\nBlocks where variable is used in the LDN.\n\n- Used as a parameter in a CALL statement.\n- Used as a target variable in a LET statement.\n- Used as a source variable in a LET or SET statement.\n\nFIGURE 5.5 VARIABLE CROSS REFERENCES\n\nStatements - The last cross reference table lists the statement numbers used in an LDN. It also provides a short description and the location of each statement.\n\nThe short description identifies the type of statement and lists the main element associated with it.\n\nLET statements are listed with their target variables.\n\nSET statements are listed with the contacts they control.\n\nGOTO statements are listed with their target statement or coil numbers.\n\nCALL statements are listed with the call routine numbers they are used with.\n\nFIGURE 5.6 STATEMENT CROSS REFERENCES\nEach LDN stored on disk may have several files associated with it. These files, identified by a ladder name and a three letter extension, include:\n\n1. (Laddername).LDN\n .LDN files which are the actual ladder diagram networks that can be used by the PIC.\n\n2. (Laddername).DEF\n .DEF files used for documentation. These files contain the labels, comments and headings used for documented LDN's.\n\n3. (Laddername).DAT\n .DAT files contain data such as the contents of non-volatile variables and the state of retentive control relays. These files may also store information generated using the Data Storage Call Routines.\n\n4. (Laddername).LIS\n .LIS files are ladder diagram and/or cross reference listings stored on disk.\n\n5. (Laddername).SCR\n .SCR files are temporary files used by the GLLADD software for cross referencing during the listing process.\n\nBecause .SCR files are deleted automatically when the listing is complete, the user will never see them on the file directory unless the listing process is interrupted.\n\n6. (Laddername).LBK\n\n7. (Laddername).DBK\n\n.LBK and .DBK files are backup files which are described in the next section.\n\n6.1 BACKUP FILES\n\nWhenever an LDN or a definition file is edited, the computer creates a backup file containing the older version of that file. For example, if a file named \"TOOLS.LDN\" is edited to include three more ladder rungs, the new file containing these rungs will be called \"TOOLS.LDN\". The previous file which did not contain these rungs will become the backup file. Its name will be changed to \"TOOLS.LBK\".\n\n\n\nFIGURE 6.1 FILE BACKUP EXAMPLE (first revision)\n\nLikewise, if a file named \"TOOLS.DEF\" is changed to include extra comments or labels, the new file will be called \"TOOLS.DEF\". The previous file which does not have these changes will become the backup file called \"TOOLS.DBK\".\n\nIf a backup file already exists and the LDN or definition file is edited again, the third or newest version of the file will become the .LDN or .DEF file. The version that was the .LDN or .DEF file will become the backup file. The original version that was the backup file will be eliminated.\nfiles. If, after changes are made, the user decides that the newer version of the file is unacceptable, the previous version will be available as the backup file. By changing the backup file to an active file, the original version will be restored as the active .LDN or .DEF file.\n\nIMPORTANT\n\nThe GLLADD software will not back up .LIS or .DAT files. If a newer version of one of these files is created, the previous version will be deleted unless it has been renamed or copied using DOS.\n\n6.2 DISK FILE HANDLER MENU\n\nDisk files are handled through the Disk File Handler menu. To access this menu, press the F4 (Disk File Handler) function key from the Main Menu.\n\n<table>\n<thead>\n<tr>\n<th>Disk File Handler</th>\n<th>Short</th>\n<th>Long</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>List a directory of the working drive, with only the filename and extension.</td>\n<td>F1 Dirc-</td>\n<td>F2 Direc-</td>\n</tr>\n<tr>\n<td></td>\n<td>tory</td>\n<td>tory</td>\n</tr>\n<tr>\n<td>Delete a file from the working drive.</td>\n<td>F3 File</td>\n<td>Change Filename</td>\n</tr>\n<tr>\n<td></td>\n<td>Delete</td>\n<td>F4 Filename</td>\n</tr>\n<tr>\n<td>Create a duplicate of a file on the working drive.</td>\n<td>F5 File</td>\n<td>Change Fileext.</td>\n</tr>\n<tr>\n<td></td>\n<td>Copy</td>\n<td>F6 Fileext.</td>\n</tr>\n<tr>\n<td></td>\n<td>F7</td>\n<td>F8</td>\n</tr>\n<tr>\n<td></td>\n<td>F9 Help</td>\n<td>Done</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>F10 <Alt> Abort</td>\n</tr>\n</tbody>\n</table>\n\nSelect an operation via the function keys.\n\nFIGURE 6.3 DISK FILE HANDLER MENU\n6.3 SHORT DIRECTORY\n\nFrom the Disk File Handler Menu, the F1 (Short Directory) function key provides a list of all files found in the working drive. This list contains only the names and extensions of each file and is useful for quickly finding out which files are stored on the disk and what the exact spelling of the file names are. At the bottom of the listing, the computer indicates the number of files found and the amount of memory available on the disk.\n\n CONTROL.DEF [Active Definition File]\nABC.DEF\nABC.LBK CONTROL.LDN\nABC.LDN STOR.DBK\nABC.LIS STOR.DEF\nC114.LDN STOR.LBK\nCOMMAND.COM STOR.DAT\n\nNumber Of Files —— 12 file(s) 275092 bytes free [Amount Of Disk Space still Available]\n\nPush any key to continue!\n\nFIGURE 6.4 SHORT DIRECTORY EXAMPLE\n\n6.4 LONG DIRECTORY\n\nThe F2 (Long Directory) function key provides a more detailed account of each file. This list includes the file name, the size of the file (in bytes of memory) and the date and time that the file was created (if a DOS clock function is used with the computer). At the bottom of the list, the computer indicates the number of files found and the amount of memory available on the disk.\n\n 134 8-07-85 2:22p\nABC.DEF\nABC.LBK 6410 8-07-85 1:54p\nABC.LDN 6435 8-07-85 2:05p\nABC.LIS 2508 8-14-85 9:49a\nC114.LDN 6547 7-08-85 2:12p\nCOMMAND.COM 17792 10-20-84 9:24a\n\nNumber Of Files —— 12 file(s) 275092 bytes free [Amount Of Disk Space still Available]\n\nPush any key to continue!\n\nFIGURE 6.5 LONG DIRECTORY EXAMPLE\n6.5 DELETING FILES\n\nThe F3 (Delete File) function key is for deleting files that are no longer needed. This should be done periodically to conserve disk space and shorten the file directories.\n\nTo delete a file, press the F3 key. Another menu will appear asking you to specify the type of file(s) to be deleted. After making a selection, the software will then request a ladder name. Enter the ladder name and press the return key.\n\nTo verify that the file(s) has been deleted, press the F1 key and check the new directory of the file names found on the disk.\n\n<table>\n<thead>\n<tr>\n<th>Delete File</th>\n<th>Delete an active definition file. (.DEF)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F1 Active Ladder File</td>\n<td>F2 Active Defin. File</td>\n</tr>\n<tr>\n<td>Delete a backup ladder file. (.LBK)</td>\n<td>Delete a backup definition file. (.DBK)</td>\n</tr>\n<tr>\n<td>F3 Backup Ladder File</td>\n<td>F4 Backup Defin. File</td>\n</tr>\n<tr>\n<td>Delete all related active and backup, ladder and definition files.</td>\n<td></td>\n</tr>\n<tr>\n<td>F5 All Related Files</td>\n<td>F6</td>\n</tr>\n<tr>\n<td>F7</td>\n<td>F8</td>\n</tr>\n<tr>\n<td>F9 Help</td>\n<td>Done <Alt> Abort</td>\n</tr>\n</tbody>\n</table>\n\nSelect an operation via the function keys.\n\n**FIGURE 6.6 DELETE FILE MENU**\n6.6 CHANGING FILENAMES\n\nIf you press the F4 (Change Filename) key, another menu will appear on the screen.\n\nThe menu selection allows you to specify the type of file(s) to be renamed. After making a selection, the software will then request the file’s ladder name. Enter the ladder name and press the return key.\n\nThe software will then ask for a new ladder name that the existing name will be changed to. Enter the new name and press the return key.\n\nTo verify that the file(s) has been renamed, press the F1 key and check the new directory of the file names found on the disk.\n\nChange File Name\n\n<table>\n<thead>\n<tr>\n<th>F1</th>\n<th>F2</th>\n<th>Change the filename of an active definition file.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>F1 Ladder File</td>\n<td>F2 Defin. File</td>\n<td>Change the filename of an active ladder file.</td>\n</tr>\n<tr>\n<td>F3</td>\n<td>F4</td>\n<td>Change the filename of a backup definition file.</td>\n</tr>\n<tr>\n<td>F3 Backup Ladder File</td>\n<td>F4 Backup Defin. File</td>\n<td></td>\n</tr>\n<tr>\n<td>F5</td>\n<td>F6</td>\n<td>Change the filename of a related ladder and definition file set.</td>\n</tr>\n<tr>\n<td>F5 Related Files</td>\n<td>F6</td>\n<td></td>\n</tr>\n<tr>\n<td>F7</td>\n<td>F8</td>\n<td></td>\n</tr>\n<tr>\n<td>F7 Help</td>\n<td>F10 <Alt> Abort</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nSelect an operation via the function keys.\n\nFIGURE 6.7 CHANGE FILE NAME MENU\n6.7 COPYING FILES\n\nTo copy a file, press the F5 (File Copy) function key. Another menu will appear asking you to specify the type of file to be copied. After making a selection, the software will then request the ladder name of the file or files you want to copy. Enter the ladder name and press the return key.\n\nThe computer will then ask you for a ladder name for the new file(s). Enter a new ladder name and a return.\n\nTo verify that the file(s) has been copied, press the F1 key and check the new directory of the file names found on the disk.\n\n<table>\n<thead>\n<tr>\n<th>Operation</th>\n<th>Function Key</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Copy a backup ladder file to active</td>\n<td>F1 Backup to Act.</td>\n</tr>\n<tr>\n<td>(.LBK to .LDN)</td>\n<td>F2 Backup to Act.</td>\n</tr>\n<tr>\n<td>Copy a backup definition file to active</td>\n<td>F3 Act. to Newname</td>\n</tr>\n<tr>\n<td>(.DBK to .DEF)</td>\n<td>F4 Act. to Newname</td>\n</tr>\n<tr>\n<td>Make a copy of an active ladder file, under a new filename.</td>\n<td>F5 Bkup. to Newname</td>\n</tr>\n<tr>\n<td>Make a copy of a backup ladder file, under a new filename.</td>\n<td>F6 Bkup. to Newname</td>\n</tr>\n<tr>\n<td>Make copies of a related ladder and definition file set under a new filename.</td>\n<td>F7 Files to Newname</td>\n</tr>\n<tr>\n<td>Done</td>\n<td>F8 Files to Newname</td>\n</tr>\n</tbody>\n</table>\n\nSelect an operation via the function keys.\n\nFIGURE 6.8 FILE COPY MENU\n6.8 CHANGING FILE EXTENSIONS\n\nThe F6 key is used for changing file extensions. By changing the extensions, active files can be changed to backup files and backup files can be changed to active files.\n\nIMPORTANT\n\nIf a backup file is changed to an active file, the active file will be automatically erased from the disk. Likewise, if an active file is changed to a backup file, the backup file will be erased.\n\nFrom the Disk File Handler Menu, press the F6 (change file extension) function key. A new menu will be displayed. This menu will provide you with several options for changing file extensions. After selecting the appropriate function key, the software will request the ladder name of the file to be changed. Enter the ladder name and press the return key to complete the operation.\n\nTo verify that the file extensions have been changed, press the F1 (short directory) function key and check the file names found on the disk.\n\nChange File Extension\n\n<table>\n<thead>\n<tr>\n<th>F1</th>\n<th>F2</th>\n</tr>\n</thead>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>F3</th>\n<th>F4</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Ladder to Bkup</td>\n<td>Defin. Active to Bkup</td>\n</tr>\n</tbody>\n</table>\n\nF5\nF6\nF7\nF8\nF9 Help\nF10 <Alt> Abort\n\nSelect an operation via the function keys.\n\nFIGURE 6.9 CHANGE FILE EXTENSION MENU\nPART TWO - PiC SUPPORT FUNCTIONS\nSECTION 7 - PiC409 AUX1 SUPPORT\n\n7.1 INTRODUCTION\n\nThe GLLADD software supports an RS-232C communications link between the computer and the G&L PiC control panel. This allows the computer to act as a terminal for the Giddings and Lewis PiC409 family.\n\nIn addition to performing all of the functions of a PiC terminal, the computer also provides mass data storage capabilities such as recording LDN’s onto disk and loading them from disk into the PiC.\n\nThe GLLADD PiC409 AUX 1 Support function allows the use of the computer as a PiC terminal. It provides a more convenient method of operating and programming the G&L PiC by using the AUX 1 mode on the PiC Control Panel.\n\nThe primary function of the AUX 1 mode is to allow the operator or programmer to use a personal computer (or programming terminal) for remote control of the PiC Mode selection.\n\nAnother important feature of the AUX 1 Mode is the User Authorization Code. This is a password created by the programmer or operator that prevents unauthorized use of the PiC. When the Mode selector switch on the PiC control panel is covered by a locked panel, the only way to access the PiC is with a programming terminal or a personal computer and the user authorization code.\n\nAll communication with an IBM or IBM compatible personal computer can be directed through the Terminal port on the PiC control panel. This eliminates the need to insert the interface cable into the Loader port on the control panel every time a LOAD, RECORD or VERIFY operation is performed for files on disk.\n\n7.2 AUX 1 SOFTWARE ON THE PIC\n\nThe AUX 1 Support function will not work unless the PiC has the proper AUX 1 software in the Compiler and CPU modules. G&L PiC409’s and PiC49’s built after July 1985 will feature the AUX 1 software.\n\nPiC’s released prior to this date can be updated with a special kit containing seven EPROM (Erasable Programmable Read Only Memory) chips. These chips contain all of the software needed to provide older PiC’s with the latest G&L version of the Compiler and CPU modules.\n\nThe following software numbers are found on the new EPROM chips. If the chips on your Compiler and CPU modules do not have the same first five digits as the numbers listed here, you do not have the updated software. If you are installing the new EPROM chips yourself, refer to the instructions supplied with the kit.\n\n<table>\n<thead>\n<tr>\n<th>COMPILER MODULE</th>\n<th>6809 CPU MODULE</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Part Number</td>\n<td>Part Number</td>\n</tr>\n<tr>\n<td>502-03174-00</td>\n<td>502-03017-21</td>\n</tr>\n</tbody>\n</table>\n\n<p>| | |</p>\n<table>\n<thead>\n<tr>\n<th></th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>88168-XX</td>\n<td>88162-XX</td>\n</tr>\n<tr>\n<td>88169-XX</td>\n<td></td>\n</tr>\n<tr>\n<td>88170-XX</td>\n<td></td>\n</tr>\n<tr>\n<td>88171-XX</td>\n<td></td>\n</tr>\n<tr>\n<td>88284-XX</td>\n<td></td>\n</tr>\n<tr>\n<td>88285-XX</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n(XX = version number)\n\n7.3 USING THE AUX 1 SUPPORT FUNCTION\n\nThere are several things to consider when using the AUX 1 mode with the GLLADD software.\n\nPiC409 AUX 1 Support\n1. The female end of the GLLADD cable must be connected to the personal computer serial port specified during the GLLADD initialization procedure (Section 2.2). The male end of the cable must be connected to the Terminal port on the PiC control panel.\n\n2. The terminal baud rate rotary switch on the PiC control panel must be set to the baud rate specified during the GLLADD initialization procedure (Section 2.2).\n\nAfter connecting the personal computer to the PiC, set the MODE switch on the PiC control panel to the AUX 1 position. Turn on the power to the computer and the PiC and start up the GLLADD software. Press the \"Pic Aux 1 Functions\" key from the GLLADD Main Menu.\n\n7.4 CREATING A USER AUTHORIZATION CODE\n\nIf the computer is set up correctly as indicated in Section 7.3, the following message will be displayed on the screen:\n\nPLEASE ENTER THE SYSTEM'S DEFAULT AUTHORIZATION CODE.\n\nType the characters \"PC409\" and press the return key. The next message that will appear is:\n\nTO DEFINE YOUR USER AUTHORIZATION CODE, ENTER 1-9 CHARACTERS FOLLOWED BY A CARRIAGE RETURN. REMEMBER THE CODE IS NOT SHOWN ON THE SCREEN, EACH TIME A CHARACTER IS ACCEPTED A \"$\" IS DISPLAYED.\n\nType in a code consisting of one to nine characters and press the return key. These characters may include any combination of the letters of the alphabet and numerals from 0 through 9.\n\nInstead of the characters you type in, the computer will only display a series of asterisks on the screen. This is to prevent an onlooker from viewing your authorization code when you type it in.\n\nThis code will be the password used to access the system through the AUX 1 Mode. From now on, this code will be required when using the AUX 1 mode.\n\nIMPORTANT\n\nAfter creating a user authorization code, write it down and store the code in a safe place. If you forget your user authorization code and do not have it written down anywhere, you must clear the memory on the PiC Support Module and repeat the procedure for setting up a new code.\n\nTo clear the memory from the PiC Support Module, turn off the power to the PiC and remove the module from the nest. Remove the IBE (internal battery enable) jumper from the module for several minutes. Return the jumper, reinsert the PiC support Module and restart the system.\n\nCAUTION: CLEARING THE MEMORY FROM THE PiC SUPPORT MODULE WILL RESULT IN THE PERMANENT LOSS OF ANY BATTERY BACKED DATA STORED ON THIS MODULE. TO SAVE NON-VOLATILE VARIABLE AND RETENTIVE RELAY DATA BEFORE REMOVING THE IBE JUMPER, READ SECTION 7.12.\n\n7.5 AUX 1 MENU SELECTION\n\nAfter entering the authorization code, the AUX 1 menu will appear on the screen.\n\nThe first seven functions are the same as the standard selection available from the MODE switch on the PiC control panel. If you are not familiar with these functions, refer to the PiC409 Family Programming Manual for instructions.\nPIC 409 AUX. 1 MODE SELECT MENU VER. 1.0\n\n1. RUN\n2. PROGRAM\n3. LOAD\n4. VERIFY\n5. RECORD\n6. AUX 2\n7. AUX 3\n\nADDITIONAL FUNCTIONS\n8. RE-DIRECT DATA I/O PORT\n9. CHANGE AUTHORIZATION\n\nTO MAKE YOUR SELECTION, ENTER THE NUMBER AND CARRIAGE RETURN. TO RETURN TO THE AUX 1 MENU FROM ANY MODE, ENTER \"CONTROL Q\".\n\nFIGURE 7.1 AUX 1 MENU\n\nTo use any of these functions, press the number from the menu to the left of the desired function followed by a return.\n\nTo leave any of the selected modes and to return to the AUX 1 menu, press the \"CTRL\" and \"Q\" keys at the same time. The PiC will ask for your user authorization code. Enter the code and press the return key.\n\nNOTE\n\nWhen entering the RUN mode (selection 1), the PiC will ask you to verify your selection by entering your selection a second time followed by a return. This is to prevent you from unintentionally entering the RUN mode.\n\nIf you enter the incorrect code, the PiC will not allow you to reenter the AUX 1 mode. Press any key to reset the code entry operation and enter your code again. When the correct code is entered, the screen will display the AUX 1 menu again.\n\nPiC409 AUX 1 Support\n\nIMPORTANT\n\nYou cannot reenter the AUX 1 mode from the RUN mode by using the \"CTRL\" and \"Q\" keys unless Real Time Debug (Call Routine C912) is installed and working in your LDN. Instead, you must switch the Mode switch on the PiC control panel out of the AUX 1 mode and then switch back to the AUX 1 mode and press the initialize button.\n\nTo avoid this situation, always include Real Time Debug with every LDN you use.\n\n7.6 REDIRECTING COMMUNICATIONS FROM THE LOADER PORT TO THE TERMINAL PORT\n\nSelect the \"RE-DIRECT DATA I/O PORT\" function by pressing the number \"8\" from the AUX 1 menu and a return. After doing so, the following line will appear on the screen:\nDATA I/O IS CURRENTLY VIA TERMINAL PORT.\n\nThis message indicates that all communications, including LOAD, VERIFY and RECORD operations, will now be performed through the Terminal port on the PiC control panel. The Loader port on the control panel will not be used.\n\nAs long as this message appears on the screen, LDN's, Call Routines and data can be transferred between a personal computer and the PiC by remote control using the computer keyboard and the PLLADD software (version 2.0 or higher).\n\nPreviously, with PLLADD version 1.4, these operations required someone to manually switch the PLLADD cable between the Loader and the Terminal ports.\n\nTo restore the use of the Loader port, select Function 8 from the AUX 1 menu a second time. After pressing the return key, the message \"DATA I/O IS CURRENTLY VIA TERMINAL PORT\" will disappear indicating that the use of the Loader port is now restored.\n\n---\n\n**NOTE**\n\nThe LOADER port will be reactivated if power to the PiC is turned off and then back on again, or if the MODE selector switch on the PiC control panel is switched out of AUX 1. Communications through the TERMINAL port must be activated every time the AUX 1 mode is initialized.\n\n---\n\n7.7 CHANGING THE AUTHORIZATION CODE FUNCTIONS\n\nTo change your authorization code or the way it works with the PiC, select function 9 from the AUX 1 menu.\n\nThe PiC will ask you to enter your authorization code. After entering the correct code, press the return key. The following menu will appear on the screen.\n\n1. CHANGE THE AUTHORIZATION CODE\n2. CODE NOT REQUIRED FOR ENTRY TO THE TERMINAL MODE\n3. CODE REQUIRED FOR ENTRY TO THE TERMINAL MODE\n\nTO MAKE YOUR SELECTION, ENTER THE NUMBER AND RETURN.\n\n**CHOICE?**\n\n**Selection 1** - If you wish to change your existing code, press \"1\" followed by a return.\n\nAfter doing this, the instructions for entering a new authorization code will appear. Enter in a new code using one to nine alphanumeric characters just as you did for the original authorization code. Press the return key. The AUX 1 menu will return to the screen.\n\n**Selection 2** - If you find it inconvenient to enter the authorization code every time you reenter the AUX 1 mode from a different mode, press \"2\" followed by a return.\n\nAfter doing this, you will no longer need to enter your authorization code as long as you remain in AUX 1 and the power is left on. The only exceptions are if you wish to change the authorization code (selection 1) or if you decide to require the use of the authorization code again (selection 3).\n\n---\n\n**NOTE**\n\nEvery time you leave and return to the AUX 1 position on the MODE selector switch, or if power to the PiC is turned off and then back on again, the system will once again require the authorization code every time you return to the AUX 1 Mode.\n7.8 LEAVING AND RETURNING TO THE AUX 1 MODE\n\nAlthough its use is highly recommended for the sake of security and convenience, the AUX 1 mode does not have to be used all of the time.\n\nBy setting the mode selector switch on the PiC control panel to a mode other than AUX 1, remote control of the PiC is terminated and the manual selection of the control control panel operations take place.\n\nTo return to the AUX 1 mode, rotate the mode selector switch on the control panel to the AUX 1 position. Press the Initialize button on the control panel.\n\nThe PiC will ask for your user authorization code. Enter the code and press the return key. The AUX 1 menu will then appear on the screen.\n\nCAUTION\n\nBecause the Aux 1 mode can be exited at any time by rotating the mode selector switch on the PiC control panel, this switch should be made inaccessible to all unauthorized personnel.\n\nThis can be accomplished by putting a locked door or panel in front of the control panel or keeping the entire PiC in a restricted area.\n\n7.9 LOADING RECORDING AND VERIFYING LDN'S ON DISK\n\nIf you are using the GLLADD software, all LDN storage functions can be performed on disk instead of the STR LINK II or III tape devices.\n\nPiC409 AUX 1 Support\n\nNOTE\n\nCommunications must be redirected from the LOADER port to the TERMINAL port to perform these operations on disk.\n\n7.9.1 Loading LDN's From Disk Into The PiC\n\nTo load an LDN into the PiC, use the following procedure.\n\n1. Choose selection 3 (load) from the AUX 1 menu.\n\n2. The computer will ask for the name of the LDN you will be loading. You must use the ladder name of an LDN that is on the disk in your working drive. Type in the ladder name press the return key.\n\n3. The computer will then load the LDN into the PiC. Use the verify function to ensure that the loading operation is successful.\n\nIMPORTANT\n\nIf Call Routines are used, an LDN created with the GLLADD Ladder Editor/Compiler, must go through a Reinstall process before it can be used in the PiC.\n\nAfter loading the LDN, enter the AUX 2 Call Routine Installer and press the \"R\" reinstall key. Refer to Section 3.11.5.4 for more information.\n\n7.9.2 Verifying LDN's On Disk And The PiC\n\nTo verify LDN's use the following procedure.\n\n1. Choose selection 4 (verify) from the AUX 1 menu.\n2. The computer will ask for the name of the LDN you will be verifying. Type in the ladder name of the LDN on the disk in your working drive that is to be verified with the LDN in the PiC.\n\n3. The computer will then verify the LDN in the PiC with the LDN on disk. If both LDN’s are identical, the computer will announce that verification is complete.\n\n4. If the verification process indicates a discrepancy between the two LDN’s, an error message, based on the problem, will be displayed.\n\n7.9.3 Recording LDN’s From The PiC Onto Disk\n\nTo record an LDN from the PiC onto a disk, use the following procedure.\n\n1. Choose selection 5 (record) from the AUX 1 menu.\n\n2. The computer will ask for the name of the LDN you will be recording. If it is a new LDN, type in a new ladder name.\n\n If you are updating an existing LDN, type in the existing ladder name. The previous version on disk will become the backup (.LBK) file and the version in the PiC will become the new active (.LDN) file.\n\n Press the return key.\n\n3. The computer will record the LDN from the PiC onto the disk. Use the verify function to insure that the recording operation is successful.\n\n7.10 LOADING, RECORDING AND VERIFYING LDN’S USING A STR LINK II OR III TAPE DEVICE\n\nIf you intend to use a STR LINK II or III to perform load, record and verify functions, you must use the LOADER port on the PiC control panel. Do not redirect the communications from this port to the TERMINAL port.\n\nThese operations are performed in the same way indicated in Section 4 of the PiC409 Family Programming Manual.\n\nNOTE\n\nBecause it is faster and more convenient to use disks, we recommend not using the STR LINK devices directly with the PiC. We suggest that any LDN’s stored on tape be copied onto disk.\n\nLDN’s stored on disk can also be copied onto tape if an STR LINK II or III is used as a backup device.\n\nRefer to Section 8.2 for information on transferring LDN’s directly between tapes and disks.\n\n7.11 INSTALLING CALL ROUTINES FROM DISK\n\nNOTE\n\nAll communications with the PiC must be redirected from the LOADER port to the TERMINAL port on the PiC control panel before loading or installing Call Routines from disk.\n\nCall Routines can be loaded directly into the PiC from the G&L Call Routine Disk. Enter the AUX 1 mode from the Main Menu. When the AUX 1 menu appears on the screen enter a “6” (AUX 2).\n\nThe AUX 2 menu will appear on the screen. If you are using a dual floppy disk system, remove the GLLADD backup disk from drive A and replace it with the Call Routine disk.\nHard disk users typically copy the Call Routines onto the hard disk so there is no need for them to swap floppy disks.\n\nChoose Selection 3 (Call Routine Installer) from the AUX 2 menu. When the asterisk prompt \"*\" appears, press the \"L\" key to load Call Routines.\n\nUse the \"I\" key to install the Call Routines. If other Call Routines are already installed, use the \"R\" (reinstall) key.\n\nThe procedure for using the Call Routine Installer is described in Section 9 of the PiC409 Family Programming Manual. The only difference is that the Calls will be loaded from the Call Routine Disk in the system drive instead of a STR LINK II or III tape device.\n\n7.12 VARIABLE AND CONTROL RELAY BACKUP\n\nThis feature allows the programmer to save the contents of non-volatile variables and the state of retentive relays on disk. This provides added protection in case of a memory failure. In the event that memory is lost, the stored data can be loaded back into the PiC using the LOAD command.\n\n7.12.1 Saving Data on Disk\n\nTo save non-volatile variable or retentive relay data, select option 5 from the AUX 2 menu. The PiC will display the following instructions:\n\nTO RECORD NON-VOLATILE VARIABLES THROUGH THE PORT, ENTER \"V\", RETURN.\n\nTO RECORD THE STATE OF NON-VOLATILE CONTROL RELAYS THROUGH THE PORT, ENTER \"C\", RETURN.\n\nTO LOAD NON-VOL. CRS OR VARIABLES, USE THE LOAD MODE OF AUX 1 OR THE ROTARY MODE SWITCH.\n\n---\n\nNOTE\n\nTo save this information on disk, all communications with the PiC must be redirected through the Terminal port.\n\nPress the \"V\" key if you want to save the contents of your non-volatile variables. Press the \"C\" key if you want to save the state of your retentive relays.\n\nThe computer will first ask you to enter a file name. Enter a name consisting of up to eight characters (press the personal computer F9 key if you need to know which characters are valid). This file name does not have to be the same as the ladder name.\n\nAfter entering the file name and a return, you will be asked to indicate whether this is a Ladder (L) or Data (D) file. Enter a \"D\" to indicate that you are saving data.\n\nThe computer will the proceed to save the data on the disk in the working drive.\n\nAfter a successful record operation, the computer will respond with the following message:\n\nCONTROL RELAYS RECORDED,\nAUTO VERIFY IN PROGRESS.\n\nThe Auto Verify function is automatic with a STR LINK device. However, when you are storing the data on disk, you must verify the accuracy of the recording by reentering the file name and a return when the computer asks for the file name a second time. When the computer asks if the file is a Ladder or Data file, press the \"D\" key.\n\nIf the verification process indicates that a file saved on tape or disk is valid, the PiC will display the following message:\n\nPiC409 AUX 1 Support\nCHANGE MODES TO EXIT. ENTER ANY KEY TO START THIS MODE OVER.\n\nWhen you are satisfied with the record operation, move to a different mode by pressing the \"CTRL\" and \"Q\" keys at the same time.\n\n7.12.2 Loading Data From Disk Or Tape\n\nBefore loading the data back into the PiC, be sure that the PiC is set up to save at least the same number of non-volatile variables and retentive relays. Otherwise, this data will be lost again when power to the PiC is shut off.\n\nTo load the non-volatile or retentive relay data back into the PiC, enter the LOAD mode from the AUX 1 menu.\n\nAfter entering this mode, the computer will ask you to enter a filename. Enter the name of the disk file containing the desired data and press the return key. The computer will then ask if the file is a Ladder or Data file. Enter a \"D\" to begin the Load operation.\n\nAfter a successful load operation, the computer will respond with the following message:\n\nCONTROL RELAYS LOADED\nAUTO VERIFY IN PROGRESS.\n\nThe Auto Verify function is automatic with a STR LINK device. However, when loading the data from disk, you must verify the accuracy of the load operation by reentering the file name and a return when the computer asks for the file name a second time. When the computer asks if the file is a Ladder or Data file, press the \"D\" key.\n\nIf the verification process indicates that the file loaded from tape or disk is valid, the PiC will display the following message:\n\nGOOD\n\nCHANGE MODES TO EXIT. ENTER ANY KEY TO START THIS MODE OVER.\n\nWhen you are satisfied with the record operation, move to a different mode by pressing the \"CTRL\" and \"Q\" keys at the same time.\nThe GLLADD Auxiliary Functions menu has several additional options using the computer's serial communications port.\n\nThese options provide control panel support and the transfer of LDN's and data files between the computer and a STR LINK II or III tape device.\n\nTo display the Auxiliary Functions Menu, press the F6 (Aux. Funcs.) function key from the Main Menu.\n\nNOTE\n\nThe GLLADD Auxiliary Functions will not operate with the G&L PC400.\n\nAuxiliary Functions\n\n<table>\n<thead>\n<tr>\n<th>Control F1 Panel Support</th>\n<th>F2</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Read F3 From a STR LINK</td>\n<td>Write F4 To a STR LINK</td>\n</tr>\n<tr>\n<td>F5</td>\n<td>F6</td>\n</tr>\n<tr>\n<td>F7</td>\n<td>F8</td>\n</tr>\n<tr>\n<td>F9 Help</td>\n<td>Done F10 <Alt> Abort</td>\n</tr>\n</tbody>\n</table>\n\nProvides for writing an LDN from an disk file to a STR LINK II/III.\n\nSelect an operation via the function keys.\n\nFIGURE 8.1 AUXILIARY FUNCTIONS MENU\n\n8.1 CONTROL PANEL SUPPORT\n\nWith the exception of transferring data files using the Data Storage Call Routines, the Control Panel Support functions are similar to the PiC409 AUX 1 functions.\n\nTo display the Control Panel Support menu, press the F1 (control panel support) function key from the Auxiliary functions menu. This menu has three choices that are described in the following text.\nNOTE\n\nWhenever possible, it is better to use the AUX 1 Support functions instead of the Control Panel Support functions because they are easier to use and can be controlled remotely from the computer.\n\nThe AUX 1 Support functions cannot be used when the PiC Compiler and CPU modules do not contain the AUX 1 software on EPROM. To determine if your PiC has this software, refer to Section 7.2 in this manual.\n\n---\n\nPiC409 Support Mode\n\n<table>\n<thead>\n<tr>\n<th>Terminal F1 Mode</th>\n<th>Mass F2 Storage Mode</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Install F3 Call Routines</td>\n<td>F4</td>\n</tr>\n<tr>\n<td>F5</td>\n<td>F6</td>\n</tr>\n<tr>\n<td>F7</td>\n<td>F8</td>\n</tr>\n<tr>\n<td>F9 Help</td>\n<td>Done F10 <Alt> Abort</td>\n</tr>\n</tbody>\n</table>\n\nSelect an operation via the function keys.\n\nFIGURE 8.2 PiC409 SUPPORT MODE MENU\n8.1.1 Terminal Mode\n\nThe F1 (terminal mode) function key on the Control Panel Support menu allows the computer to act as a \"dumb\" terminal for PiC409 family.\n\nAfter pressing the F1 key, the computer will provide instructions for establishing the proper link between the computer and the PiC. Follow these instructions carefully.\n\nAfter the link is established, select the desired mode on the PiC control panel and press the initialize button. The computer will now perform all of the functions of a Lear Siegler ADM3A or Televideo 910 Plus terminal.\n\nIf you want to leave the terminal mode at anytime, press the \"Alt\" and F10 keys at the same time.\n\n8.1.2 Mass Storage Mode\n\nThe Mass Storage Mode provides for the transfer of files between the computer and the G&L PiC. The file transfer operations include:\n\n1. Recording LDN's and data files from the PiC onto disk.\n2. Loading the files from disk into the PiC.\n3. Verifying that the file transfers are accurate.\n\nIf you are transferring Ladder (LDN) files, read Section 8.1.2.1. If you are transferring data files used by the Data Storage Call Routines, read Section 8.1.2.2.\n\n8.1.2.1 Transferring LDN's Between The Computer And The PiC - Press the F2 (mass storage mode) function key from the Control Panel Support Menu. The computer will display the following message:\n\nEnter the filename (<F9> for help, <Alt><F10> to abort):\n\n8.1.2.2 Transferring Data Files Between The Computer And The PiC - Press the F2 (mass storage mode) function key from the Control Panel Support Menu. The computer will display the following message:\n\nEnter the filename (<F9> for help, <Alt><F10> to abort:\n\nEnter the name of the file and press the return key. The computer will respond with this question:\n\nPlease indicate whether this is a Ladder or Data file (L/D)?\n\nPress the \"L\" key. The computer will provide instructions for establishing the proper link between the computer and the PiC using the LOADER port on the PiC control panel.\n\nWhen the proper link is established, you may select the LOAD, RECORD or VERIFY modes using the rotary switch on the PiC control panel. Instructions for using these modes are covered in Section 4 of the PiC409 Family Programming Manual.\n\nWhen the operation is complete, the GLLADD software will return the computer to the Control Panel Support Menu.\n\nIMPORTANT\n\nIf Call Routines are used, an LDN created with the GLLADD Ladder Editor/Compiler, must go through a Reinstall process before it can be used in the PiC.\n\nAfter loading the LDN, enter the AUX 2 Call Routine Installer and press the \"R\" reinstall key. Refer to Section 3.11.5.4 for more information.\nPlease indicate whether this is a Ladder or Data file (L/D)?\n\nPress the \"D\" key. A series of instructions will appear on the screen. IGNORE THESE INSTRUCTIONS AND FOLLOW THE NEXT PROCEDURE INSTEAD!\n\nIMPORTANT\n\nDo not use the LOAD, RECORD or VERIFY modes on the PiC Control Panel when transferring files with the Data Storage Call Routines. The PiC must be in the RUN mode for Data Storage to work.\n\n1. Connect the computer to the LOAD-ER port on the PiC Control Panel.\n\n2. Set the Loader Baud Rate switch on the PiC Control Panel to the 9600 position.\n\n3. If the PiC is not in the RUN mode, set the mode switch on the PiC Control Panel to RUN and press the initialize button.\n\n4. The LOAD, RECORD and VERIFY operations will be handled in the LDN by the Data Storage Tape I/O Call Routine B312. The computer will operate just like a STR LINK tape device it is set up as indicated in this section.\n\nRefer to the PiC409 Family Standard Call Routine Manual for specific instructions regarding the use of the Data Storage Call Routines.\n\n8.1.3 Installing Call Routines\n\nCall Routines can be installed directly into the PiC from a G&L Call Routine Disk using the Control Panel Support menu.\n\nNOTE\n\nThis method of installing Call Routines is a remnant from a previous version of the GLLADD software. Although it is perfectly capable of loading and installing Call Routines from disk, it is more cumbersome than the newer methods now available.\n\nWe strongly suggest that you install the Call Routines using the GLLADD Ladder Editor/Compiler (See Section 3.11.5 in this manual) or the PiC AUX 1 Support functions (See Section 7.11 in this manual).\n\nInsert the G&L Call Routine disk in the working drive and press the F3 (install Call Routines) function key from the Control Panel Support Menu. The computer will provide instructions for loading the Call Routines into the PiC.\n\nAfter the calls are loaded, they must be installed. The software will instruct you to enter the AUX 2 mode on the PiC. After entering this mode, the computer is used as a \"dumb\" terminal for the PiC. Call Routines are then installed by selecting the third option in the AUX 2 mode (Call Routine Installer), and using the install (I) or reinstall (R) commands in the usual manner.\n\nWhen the operation is completed, press the escape (ESC) key and then the F10 key on the function keypad. The Control Panel Support Menu will return to the screen.\n\n8.2 USING A STR LINK II OR III\n\nAlthough the disk drives are the easiest method for storing and loading user memory, many users will still require a STR LINK II or STR LINK III for handling data. The F3 (read from a STR LINK) and F4 (Write to a STR LINK) function keys on the Auxiliary\nfunctions menu provides support for both of these tape devices.\n\nThere are several reasons for using a STR LINK with the computer. LDN's saved on tape may now be uploaded directly to a computer disk. Also, if the computer is located too far away from the PiC, the STR LINK may be used to transfer LDN's back and forth without moving or reconfiguring either system.\n\n8.2.1 Connecting The STR LINK II Or III To The Computer\n\nThe same cable used for connecting the computer to the PiC can be used for connecting the computer to the STR LINK tape device.\n\n1. Connect the female end of the cable to the 25 pin connector of the serial port you specified during the GLLADD initialization procedure (Section 2.2).\n\n2. Connect the male end of the cable to the 25 pin Data Terminal Interface connector on the STR LINK II or III tape device.\n\n3. Set the switches for the STR LINK device as indicated in Appendix C of the PiC409 Family User's Manual.\n\n8.2.2 Saving An LDN From Tape Onto Disk\n\nTo save an LDN from a tape onto a disk, press the F3 (Read From A STR Link) function key from the Auxiliary Functions menu. The computer will then request that you specify the type of tape device used.\n\nEnter a \"2\" for a STR LINK II cassette recorder or a \"3\" for a STR LINK III data cartridge recorder.\n\nInstructions for using the specified tape device with the computer will appear.\n\nAfter setting up the STR LINK as directed, press the return key.\n\nThe computer will ask for a ladder name. Type in a new ladder name and press the return key.\n\nIf the LDN is to be a revision of an existing LDN, you may use the same ladder name. The previous LDN will then become the backup (.LBK) file and the LDN on the tape will become the active (.LDN) file.\n\nAfter entering the ladder name the computer will copy the LDN stored on tape onto the disk in the working drive. When the operation is completed, the Auxiliary Functions Menu will appear on the screen.\n\n8.2.3 Saving An LDN From Disk Onto Tape\n\nTo save an LDN from a disk onto a tape, press the F4 (write to a STR Link) function key from the Auxiliary Functions menu. The computer will then request that you specify the type of tape device used.\n\nEnter a \"2\" for a STR LINK II cassette recorder or a \"3\" for a STR LINK III data cartridge recorder.\n\nInstructions for using the specified tape device with the computer will appear. After setting up the STR LINK as directed, press the return key.\n\nThe computer will ask for a ladder name. Type in the name of the ladder on the disk that you wish to copy and press the return key.\n\nAfter entering the ladder name the computer will copy the LDN stored on the disk in the working drive to the tape in the STR LINK unit. When the operation is completed, the Auxiliary Functions Menu will appear on the screen.\nPART THREE - APPENDIX\nMain Menu\nG&L Pic Ladder Development System\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>Edit/ F1 Compile Ladder</th>\n<th>Edit F2 Document Database</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>List F3 Document Ladder</td>\n<td>Disk F4 File Handler</td>\n<td></td>\n</tr>\n<tr>\n<td>Pic409 F5 Aux. 1 Support</td>\n<td>Aux. F6 Funcs.</td>\n<td></td>\n</tr>\n<tr>\n<td>F7</td>\n<td>F8</td>\n<td>Done F10 <Alt> Abort</td>\n</tr>\n<tr>\n<td>F9</td>\n<td>Help</td>\n<td>Done F10 <Alt> Abort</td>\n</tr>\n</tbody>\n</table>\n\nLadder Editor/Compiler\n\nF1 Display F2 Search\nF3 Insert F4 Modify\nF5 Copy F6 Nova\nF7 Delete F8 Aux.\nF9 Help Done F10 <Alt> Abort\n\nLadder Editor/Compiler Auxiliary Functions\n\nReinitialize F1 F2 Allocate Memory\nF3 Name Ladder F4 Format Messages\nF5 Install Call Routines F6 Change Timer Incr.\nF7 F8\nF9 Help Done F10 <Alt> Abort\n\nMessage Formatter\n\nF1 Display F2 Insert\nF3 Delete F4 Renumber\nF5 Format F6 Edit\nF7 F8\nF9 Help Done F10 <Alt> Abort\n\nAuxiliary Functions\n\nControl Panel Support\nF1 F2\nF3 Read From a STR LINK F4 Write To a STR LINK\nF5 F6\nF7 F8\nF9 Help Done F10 <Alt> Abort\n\nPic409 Support Mode\n\nTerminal F1 Mode F2 Mass Storage Mode\nF3 Install Call Routines F4\nF5 F6\nF7 F8\nF9 Help Done F10 <Alt> Abort\n\nFIGURE A.1 GLLADD MENU STRUCTURE\nAPPENDIX B - CONNECTING CABLE\n\nG&L Part No. 503-15463-00\n\nData is transmitted between the computer and the Giddings and Lewis Programmable industrial Computer (PiC) or STR LINK tape devices via a connecting cable. This cable uses a female, 25 pin \"D\" connector at the computer end and a male, 25 pin \"D\" connector at the PiC/Tape device end. The same cable is used for both the PiC and the tape loaders.\n\nThe schematic diagram shows the cable's pin configurations and wire descriptions.\n\nAttach the female end of the cable supplied with the GLLADD package to the serial port specified during the GLADD initialization procedure (Section 2.2).\n\nThe other end of the cable can be attached to either the LOADER or TERMINAL sockets of the PiC control panel or to the DATA TERMINAL INTERFACE socket on the STR LINK tape loaders. The GLADD software will indicate when these sockets are to be used.\n\n![Diagram showing cable connections between computer, G&L PiC or STR LINK II or III, and tape loader.]\n\nThe table below shows the pin and wire descriptions:\n\n<table>\n<thead>\n<tr>\n<th>Computer Serial Port Pin Number</th>\n<th>Wire Description</th>\n<th>G&L PiC or STR LINK II or III Pin Number</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2</td>\n<td>Transmit Data From Computer</td>\n<td>2</td>\n</tr>\n<tr>\n<td>3</td>\n<td>Transmit Data From G&L PiC or STR LINK</td>\n<td>3</td>\n</tr>\n<tr>\n<td>7</td>\n<td>Signal Ground</td>\n<td>7</td>\n</tr>\n</tbody>\n</table>\n\nFIGURE B.1 CABLE SCHEMATIC\n\nAppendix B\n### APPENDIX C - INDEX OF ILLUSTRATIONS\n\n#### PART ONE LADDER DEVELOPMENT AND DOCUMENTATION\n\n**Section 1 - Introduction**\n\n- **Figure 1.1** Write Protect Tab .................................................. 1-1\n\n**Section 2 - Start-up**\n\n- **Figure 2.1** Typical Dual Floppy Disk System .................................. 2-2\n- **Figure 2.2** Suggested Hard Disk Configuration .................................. 2-4\n- **Figure 2.3** Main Menu ...................................................................... 2-9\n\n**Section 3 - Ladder Editor/Compiler**\n\n- **Figure 3.1** Ladder Editor/Compiler Menu ........................................ 3-3\n- **Figure 3.2** Example Ladder Diagram Circuits (LDC’s) ......................... 3-4\n- **Figure 3.3** LET Statement Example ................................................ 3-5\n- **Figure 3.4** SET Statement Example ................................................ 3-6\n- **Figure 3.5** GOTO Statement Example ............................................. 3-6\n- **Figure 3.6** CALL Statement Example ............................................. 3-6\n- **Figure 3.7** Search Mode Example ................................................... 3-8\n- **Figure 3.8** Insert Example ............................................................... 3-10\n- **Figure 3.9** Modify Mode Screen Format ........................................... 3-11\n- **Figure 3.10** Clear Rung Example ...................................................... 3-12\n- **Figure 3.11** Clear Column Example .................................................. 3-12, 13\n- **Figure 3.12** Compress Rung Example ............................................. 3-13\n- **Figure 3.13** Compress Column Example ........................................... 3-14\n- **Figure 3.14** Expand Rung Example .................................................. 3-14, 15\n- **Figure 3.15** Expand Column Example ............................................. 3-15\n- **Figure 3.16** Inserting A Horizontal Short ........................................ 3-16\n- **Figure 3.17** Branch Examples ......................................................... 3-17\n- **Figure 3.18** Statement Elements ..................................................... 3-18\n- **Figure 3.19** Copy Example .............................................................. 3-19\n- **Figure 3.20** Move Example .............................................................. 3-21\n- **Figure 3.21** Delete Example ............................................................ 3-22\n- **Figure 3.22** Editor/Compiler Auxiliary Functions Menu .................... 3-23\n- **Figure 3.23** Message Formatter Menu ............................................. 3-25\n- **Figure 3.24** CRT Configuration Menu ............................................. 3-27\nSection 4 - Ladder Documenter\n\n<table>\n<thead>\n<tr>\n<th>Figure</th>\n<th>Description</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>4.1</td>\n<td>Sample Documented LDN</td>\n<td>4-1</td>\n</tr>\n<tr>\n<td>4.2</td>\n<td>Documentation Database Editor Menu</td>\n<td>4-2</td>\n</tr>\n<tr>\n<td>4.3</td>\n<td>Add Or Modify Menu</td>\n<td>4-3</td>\n</tr>\n<tr>\n<td>4.4</td>\n<td>Add Or Modify Example</td>\n<td>4-3</td>\n</tr>\n<tr>\n<td>4.5</td>\n<td>Contact Label Example</td>\n<td>4-4</td>\n</tr>\n<tr>\n<td>4.6</td>\n<td>Variable Label Example</td>\n<td>4-4</td>\n</tr>\n<tr>\n<td>4.7</td>\n<td>Comment Example</td>\n<td>4-5</td>\n</tr>\n<tr>\n<td>4.8</td>\n<td>Heading Example</td>\n<td>4-6</td>\n</tr>\n<tr>\n<td>4.9</td>\n<td>Delete Menu</td>\n<td>4-7</td>\n</tr>\n<tr>\n<td>4.10</td>\n<td>Delete Example</td>\n<td>4-7</td>\n</tr>\n<tr>\n<td>4.11</td>\n<td>Copy Menu</td>\n<td>4-8</td>\n</tr>\n<tr>\n<td>4.12</td>\n<td>Copy Example</td>\n<td>4-9</td>\n</tr>\n<tr>\n<td>4.13</td>\n<td>Move Menu</td>\n<td>4-9</td>\n</tr>\n<tr>\n<td>4.14</td>\n<td>Move Example</td>\n<td>4-10</td>\n</tr>\n</tbody>\n</table>\n\nSection 5 - Listing A Documented LDN\n\n<table>\n<thead>\n<tr>\n<th>Figure</th>\n<th>Description</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>5.1</td>\n<td>Example Contact Cross References Within The LDN</td>\n<td>5-2</td>\n</tr>\n<tr>\n<td>5.2</td>\n<td>Example Coil Cross References Within The LDN</td>\n<td>5-2</td>\n</tr>\n<tr>\n<td>5.3</td>\n<td>Messages</td>\n<td>5-3</td>\n</tr>\n<tr>\n<td>5.4</td>\n<td>Contact Cross References</td>\n<td>5-3</td>\n</tr>\n<tr>\n<td>5.5</td>\n<td>Variable Cross References</td>\n<td>5-4</td>\n</tr>\n<tr>\n<td>5.6</td>\n<td>Statement Cross References</td>\n<td>5-4</td>\n</tr>\n</tbody>\n</table>\n\nSection 6 - Disk File Handler\n\n<table>\n<thead>\n<tr>\n<th>Figure</th>\n<th>Description</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>6.1</td>\n<td>File Backup Example (first revision)</td>\n<td>6-1</td>\n</tr>\n<tr>\n<td>6.2</td>\n<td>File Backup Example (second revision)</td>\n<td>6-2</td>\n</tr>\n<tr>\n<td>6.3</td>\n<td>Disk File Handler Menu</td>\n<td>6-2</td>\n</tr>\n<tr>\n<td>6.4</td>\n<td>Short Directory Example</td>\n<td>6-3</td>\n</tr>\n<tr>\n<td>6.5</td>\n<td>Long Directory Example</td>\n<td>6-3</td>\n</tr>\n<tr>\n<td>6.6</td>\n<td>Delete File Menu</td>\n<td>6-4</td>\n</tr>\n<tr>\n<td>6.7</td>\n<td>Change File Name Menu</td>\n<td>6-5</td>\n</tr>\n<tr>\n<td>6.8</td>\n<td>File Copy Menu</td>\n<td>6-6</td>\n</tr>\n<tr>\n<td>6.9</td>\n<td>Change File Extension Menu</td>\n<td>6-7</td>\n</tr>\n</tbody>\n</table>\nPART TWO - PiC SUPPORT FUNCTIONS\n\nSection 7 - PiC409 AUX 1 Support\n\nFigure 7.1 AUX 1 Menu ..................................................... 7-3\n\nSection 8 - GLLADD Auxiliary Functions\n\nFigure 8.1 Auxiliary Functions Menu ..................................... 8-1\nFigure 8.2 PiC409 Support Mode Menu ................................. 8-2\n\nPART THREE - APPENDIX\n\nAppendix A - GLLADD Menu Structure\n\nFigure A.1 GLLADD Menu Structure .................................... 1,2\n\nAppendix B - Connecting Cable\n\nFigure B.1 Cable Schematic .................................................. 1\n\nAppendix C"}}},{"rowIdx":66,"cells":{"id":{"kind":"string","value":"6ee26eff68f2e06470f589ae6441af923ef3a838"},"text":{"kind":"string","value":"Toolkit Feature\nInstallation and Customization Guide\n\nRelease 6\nNinth Edition (July 2008)\n\nThis edition applies to IBM High Level Assembler for z/OS & z/VM & z/VSE Toolkit Feature, Release 6, Program Number 5696-234 and to any subsequent releases until otherwise indicated in new editions. Make sure you are using the correct edition for the level of the product.\n\nOrder publications through your IBM representative or the IBM branch office serving your locality. Publications are not stocked at the address below.\n\nA form for reader’s comments is provided at the back of this publication. If the form has been removed, address your comments to:\n\nIBM Corporation\nReader Comments\nDTX/E269\n555 Bailey Avenue\nSAN JOSE, CA 95141-1003\nU.S.A.\n\nWhen you send information to IBM, you grant IBM a nonexclusive right to use or distribute the information in any way it believes appropriate without incurring any obligation to you.\n\n© Copyright International Business Machines Corporation 1997, 2008. All rights reserved.\nUS Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp.\nContents\n\nAbout this book .......................... vii\nBrief overview of HLASM Toolkit Feature ........................ vii\nWho should use this book .......................... vii\n Experienced users installing on z/OS ........................ viii\n Experienced users installing on z/VM ........................ viii\n Experienced users installing on z/VSE ........................ viii\nTerminology in this book .......................... viii\nList of APARs and PTFs in this book .......................... viii\nOther documentation you might need .......................... viii\nSyntax notation ................................ viii\nHow to send your comments .......................... x\n\nSummary of changes ................................ xiii\n\nPart 1. On z/OS: planning for, installing, and maintaining High Level Assembler Toolkit Feature .......................... 1\n\nChapter 1. Planning for installing\nHLASM Toolkit Feature on z/OS .......................... 3\nWorksheet: Planning for installing HLASM Toolkit\nFeature on z/OS ................................ 3\nWhat you receive with HLASM Toolkit Feature ........................ 4\n Distribution media ................................ 4\n Basic material ................................ 4\n Optional material ................................ 4\n Program publications and softcopy ................................ 4\nWhat you need to install HLASM Toolkit Feature ........................ 5\n Required and optional software for the target system ........................ 5\n DASD storage required for the target system ........................ 6\n| FMIDs deleted ................................ 8\nInstalling with CBPDO ................................ 8\nPlanning to use SMP/E ................................ 9\nPlanning to change installation jobs .......................... 9\nProgram support ................................ 9\n Program services ................................ 9\n Preventive Service Planning ................................ 9\n Statement of support procedures ................................ 9\nProgram and service level information .......................... 10\n Program level information ................................ 10\n Service level information ................................ 10\n Cumulative service tape ................................ 10\nPublications useful during installation .......................... 10\nPlanning to install in the link pack area .......................... 11\nToolkit product enablement ................................ 11\n\nChapter 2. Installing HLASM Toolkit\nFeature on z/OS .......................... 13\nOverview of installation ................................ 13\n Modifying HLASM Toolkit Feature jobs ................................ 13\n If using a CBPDO ................................ 13\n Installation checklist ................................ 13\n\nStep 1: SMP/E considerations for installing HLASM Toolkit Feature ........................ 14\n SMP/E environment ................................ 14\n SMP/E options subentry values ................................ 14\nStep 2: Copy the sample JCL from the product tape .......................... 15\nStep 3: Set up ISPF editor macro (optional) .......................... 15\nStep 4: Perform SMP/E receive .......................... 15\n Method 1: Receive using SMP/E dialogs ........................ 15\n Method 2: Receive using a batch job ........................ 16\nStep 5: Allocate target and distribution libraries .......................... 16\nStep 6: Create DDDEF entries .......................... 16\nStep 7: Perform SMP/E apply .......................... 17\n Method 1: Apply using SMP/E dialogs ........................ 17\n Method 2: Apply using a batch job ........................ 17\nStep 8: Run the installation verification program .......................... 18\nStep 9: Perform SMP/E accept .......................... 18\n Method 1: Accept using SMP/E dialogs ........................ 18\n Method 2: Accept using a batch job ........................ 18\nStep 10: Download Program Understanding Tool .......................... 19\n Step 11: Define Interactive Debug Facility to VTAM ........................ 19\n\nChapter 3. Maintaining HLASM Toolkit\nFeature on z/OS .......................... 21\nRe-installing HLASM Toolkit Feature .......................... 21\nApplying service updates .......................... 21\n What you receive ................................ 21\n Checklist for applying service .......................... 21\nStep 1: Prepare to install service .......................... 22\nStep 2: Receive the service .......................... 22\nStep 3: Accept applied service (optional) .......................... 22\nStep 4: Apply the service .......................... 22\nStep 5: Test the service .......................... 22\nStep 6: Accept the service .......................... 22\nStep 7: Service on Program Understanding Tool .......................... 22\nRemoving HLASM Toolkit Feature .......................... 23\nReporting a problem with HLASM Toolkit Feature .......................... 23\nObtaining service information .......................... 23\n\nPart 2. On z/VM: planning for, installing, and maintaining High Level Assembler Toolkit Feature .......................... 25\n\nChapter 4. Planning for installing\nHLASM Toolkit Feature on z/VM .......................... 27\nWorksheet: Planning for installing HLASM Toolkit\nFeature on z/VM ................................ 27\nWhat you receive with HLASM Toolkit Feature .......................... 27\n Distribution media ................................ 28\n Basic material ................................ 28\n Optional material ................................ 28\n Cumulative service tape ................................ 28\n Program publications and softcopy ................................ 28\nWhat you need to install HLASM Toolkit Feature .......................... 29\nOperating system requirements .......................... 29\nAppendix A. HLASM Toolkit Feature Service .......................... 79\n\nAppendix B. Create Product Parameter File (PPF) override (z/VM). .......... 81\n\nAppendix C. Planning for installing Program Understanding Tool on Windows .............................................. 83\nWorksheet: Planning for installing Program Understanding Tool on Windows ............... 83\nVerify workstation requirements ........................................... 83\nVerify workstation software ............................................... 83\nVerify host connectivity ................................................... 83\nUseful publications .......................................................... 83\n\nAppendix D. Installing Program Understanding Tool on Windows .......... 85\nWorksheet: Installing Program Understanding Tool on Windows .................. 85\nStep 1: Prepare for installation ............................................ 85\n Preparing from z/OS .................................................. 85\n Preparing from z/VM ............................................... 85\n Preparing from z/VSE .............................................. 86\nStep 2: Download the product files ..................................... 86\n Downloading from z/OS ............................................ 86\n\n Downloading from z/VM ............................................ 86\n Downloading from z/VSE .......................................... 87\nStep 3: Start the install ................................................. 88\nStep 4: Verify successful installation .................................. 88\n\nAppendix E. Maintaining Program Understanding Tool on Windows ........ 89\nMaintaining Program Understanding Tool ................................ 89\nUninstalling Program Understanding Tool from Windows .................. 89\nTasks ................................................................. 89\n\nBibliography .......................................................... 91\nHigh Level Assembler Publications ..................................... 91\nToolkit Feature Publications ............................................. 91\nRelated Publications (Architecture) ..................................... 91\nRelated Publications for z/OS ......................................... 91\nRelated Publications for z/VM ........................................ 91\nRelated Publications for z/VSE ...................................... 92\n\nGlossary .......................................................... 93\n\nNotices .......................................................... 101\nTrademarks ......................................................... 102\n\nIndex .......................................................... 103\nAbout this book\n\nThis book provides information needed to plan for, install, customize and maintain HLASM Toolkit Feature on z/OS and z/VM and z/VSE.\n\nThroughout this book, we use these indicators to identify platform-specific information:\n\n- Prefix the text with platform-specific text (for example, “Under CMS...”)\n- Add parenthetical qualifications (for example, “(CMS)”) \n- Marking lines above and below the text. Here are some of the marking lines we use:\n\n z/OS\n Informs you of information specific to z/OS.\n\n End of z/OS\n\n z/VM\n Informs you of information specific to z/VM.\n\n End of z/VM\n\n z/VSE\n Informs you of information specific to z/VSE.\n\n End of z/VSE\n\nCMS is used in this manual to refer to Conversational Monitor System on z/VM®.\n\nBrief overview of HLASM Toolkit Feature\n\nHLASM Toolkit Feature is an IBM® licensed program that helps you in the development of programs and subroutines using assembler language. This product provides an interactive debugging facility along with a disassembler, a suite of structured programming macros, a program understanding tool, (sometimes referred to as ASMPUT), a source code cross reference facility, and a comparison and search facility.\n\nWho should use this book\n\nThis book is for system programmers and system administrators who plan for, install, customize, and maintain the HLASM Toolkit Feature on z/OS or z/VM or z/VSE.\n\nTo use this book, you need to be familiar with the z/OS or z/VM or z/VSE operating system, the publications that describe your system, and job control language (JCL) or EXEC processing.\nExperienced users installing on z/OS\n\nIf you are installing on z/OS and are experienced in installing products with SMP/E, use the following fast path items:\n\n1. DASD storage for target and distribution libraries is in Table 7 on page 7 and Table 8 on page 8.\n2. DASD storage for SMP/E data sets is outlined in Table 5 on page 7 and Table 6 on page 7.\n3. Carry out steps \"Step 1: SMP/E considerations for installing HLASM Toolkit Feature\" on page 14 through to \"Step 8: Run the installation verification program\" on page 18.\n\nExperienced users installing on z/VM\n\nIf you are installing on z/VM and are experienced in installing products with VMSES/E, use the following fast path items:\n\n1. Refer to Table 20 on page 30 for DASD storage requirements.\n2. Carry out steps \"Step 1: Prepare to install HLASM Toolkit Feature\" on page 33 through to \"Step 5: Put HLASM Toolkit Feature into production\" on page 40.\n\nExperienced users installing on z/VSE\n\nIf you are installing on z/VSE and are experienced in installing products with z/VSE, use the following fast path items:\n\n1. Refer to Table 30 on page 57 and Table 31 on page 58 for DASD storage requirements.\n2. Carry out steps \"Step 1: Allocate space for the library (omit if using the default)\" on page 61 through to \"Step 4: Verify the installation of HLASM Toolkit Feature\" on page 68.\n\nTerminology in this book\n\nFor simplicity, many of the full IBM product names are shortened to just the generic acronym. For example, MVS is used to mean z/OS.\n\nList of APARs and PTFs in this book\n\nThis book includes the numbers for APARs and PTFs that are included in this product (see Appendix A, “HLASM Toolkit Feature Service,” on page 79). You might want to use this list, for example, to determine whether a fix that you have applied to the previous release is in this release that is to be installed.\n\nTo obtain current service recommendations and to identify current product service requirements, get the Preventive Service Planning (PSP) information or check with the IBM Support Center.\n\nOther documentation you might need\n\nThe complete list of HLASM Toolkit Feature publications and order numbers are listed on page 4, page 28 and page 56. Publications for related IBM products are in the \"Bibliography\" on page 91.\n\nSyntax notation\n\nThroughout this book, syntax descriptions use the structure defined below.\n• Read the syntax diagrams from left to right, from top to bottom, following the path of the line.\n The \\textit{\\textgreater\\textgreater} symbol indicates the beginning of a statement.\n The \\textit{\\textless\\textless} symbol indicates that the statement syntax is continued on the next line.\n The \\textit{\\textgreater\\textless} symbol indicates that a statement is continued from the previous line.\n Diagrams of syntactical units other than complete statements start with the \\textit{\\textgreater\\textless} symbol and end with the \\textit{\\textless\\textless} symbol.\n• \\textbf{Keywords} appear in uppercase letters (for example, \\textit{ASPACE}) or upper and lower case (for example, \\textit{PATHFile}). They must be spelled exactly as shown. Lower case letters are optional (for example, you could enter the \\textit{PATHFile} keyword as \\textit{PATHF}, \\textit{PATHFI}, \\textit{PATHFIL} or \\textit{PATHFILE}).\n• \\textbf{Variables} appear in all lowercase letters in a special typeface (for example, \\textit{integer}). They represent user-supplied names or values.\n• If punctuation marks, parentheses, or such symbols are shown, they must be entered as part of the syntax.\n• Required items appear on the horizontal line (the main path).\n\n\\begin{center}\n\\textbf{INSTRUCTION} \\textbf{required item}\n\\end{center}\n\n• Optional items appear below the main path. If the item is optional and is the default, the item appears above the main path.\n\n\\begin{center}\n\\textbf{INSTRUCTION} \\textbf{default item}\n\\textbf{optional item}\n\\end{center}\n\n• When you can choose from two or more items, they appear vertically in a stack. If you \\textbf{must} choose one of the items, one item of the stack appears on the main path.\n\n\\begin{center}\n\\textbf{INSTRUCTION} \\textbf{required choice1}\n\\textbf{required choice2}\n\\end{center}\n\nIf choosing one of the items is optional, the whole stack appears below the main path.\n\n\\begin{center}\n\\textbf{INSTRUCTION} \\textbf{optional choice1}\n\\textbf{optional choice2}\n\\end{center}\nSyntax notation\n\n- An arrow returning to the left above the main line indicates an item that can be repeated. When the repeat arrow contains a separator character, such as a comma, you must separate items with the separator character.\n\nA repeat arrow above a stack indicates that you can make more than one choice from the stacked items, or repeat a single choice.\n\nThe following example shows how the syntax is used.\n\nFormat\n\nA B C\n\noptional item\n\nINSTRUCTION fragment\n\nNotes:\n1 operand choice2 and operand choice3 must not be specified together\n\nA The item is optional, and can be coded or not.\nB The INSTRUCTION key word must be specified and coded as shown.\nC The item referred to by “fragment” is a required operand. Allowable choices for this operand are given in the fragment of the syntax diagram shown below “fragment” at the bottom of the diagram. The operand can also be repeated. That is, more than one choice can be specified, with each choice separated by a comma.\n\nHow to send your comments\n\nYour feedback is important to us in helping us to provide accurate, high-quality information. If you have comments about this document or any other HLASM Toolkit Feature documentation, contact us in one of these ways:\n\n- Use the Online Readers’ Comment Form at\nHow to send your comments\n\nwww.ibm.com/software/awdtools/rcf/\n\nBe sure to include the name of the document, the publication number of the document, the version of HLASM Toolkit Feature and, if applicable, the specific location (for example, page number) of the text that you are commenting on.\n\n- Fill out the Readers’ Comment Form at the back of this document, and return it by mail or give it to an IBM representative. If the form has been removed, address your comments to:\n IBM Corporation\n Reader Comments\n DTX/E269\n 555 Bailey Avenue\n San Jose, CA, 95141-9989\n U.S.A.\n- E-Mail your comments to this address: comments@us.ibm.com\n\nWhen you send information to IBM, you grant IBM a nonexclusive right to use or distribute the information in any way it believes appropriate without incurring any obligation to you.\nSummary of changes\n\nDate of publication\nJuly 2008\n\nForm of publication\nNinth Edition, GC26-8711-08\n\nThere are no major changes to the installation and customization procedures for HLASM Toolkit Feature with release 6.\n\nInstallation instructions for HLASM Toolkit feature release 6 on VM are provided for z/VM only. No reference is made to VM/ESA®, as VM/ESA is no longer a supported product. Installation instructions for installing any part of the product on OS/2® have also been removed.\n\nAny reference to obsolete DASD devices has been removed from the z/VSE chapters.\n\nFor information about changes to the HLASM Toolkit Feature product in release 6, please refer to [HLASM General Information]\nPart 1. On z/OS: planning for, installing, and maintaining High Level Assembler Toolkit Feature\n\nChapter 1. Planning for installing HLASM Toolkit Feature on z/OS\n\nWorksheet: Planning for installing HLASM Toolkit Feature on z/OS ............... 3\nWhat you receive with HLASM Toolkit Feature ........................................... 4\n Distribution media .................................................................................. 4\n Basic material ......................................................................................... 4\n Optional material .................................................................................... 4\n Program publications and softcopy ............................................................ 4\nWhat you need to install HLASM Toolkit Feature ........................................... 5\n Required and optional software for the target system ............................... 5\n DASD storage required for the target system ............................................. 6\nFMIDs deleted .............................................................................................. 8\nInstalling with CBPDO .................................................................................. 8\nPlanning to use SMP/E .............................................................................. 9\nPlanning to change installation jobs .............................................................. 9\nProgram support .......................................................................................... 9\n Program services ...................................................................................... 9\n Preventive Service Planning ...................................................................... 9\n Statement of support procedures ............................................................. 9\nProgram and service level information ......................................................... 10\n Program level information ....................................................................... 10\n Service level information ........................................................................ 10\n Cumulative service tape .......................................................................... 10\nPublications useful during installation .......................................................... 10\nPlanning to install in the link pack area .......................................................... 11\nToolkit product enablement .......................................................................... 11\n\nChapter 2. Installing HLASM Toolkit Feature on z/OS ................................................. 13\nOverview of installation ............................................................................. 13\n Modifying HLASM Toolkit Feature jobs .................................................. 13\n If using a CBPDO ..................................................................................... 13\n Installation checklist ............................................................................... 13\nStep 1: SMP/E considerations for installing HLASM Toolkit Feature ............... 14\n SMP/E environment ............................................................................... 14\n SMP/E options subentry values ............................................................. 14\nStep 2: Copy the sample JCL from the product tape ...................................... 15\nStep 3: Set up ISPF editor macro (optional) .................................................. 15\nStep 4: Perform SMP/E receive .................................................................. 15\n Method 1: Receive using SMP/E dialogs ................................................ 15\n Method 2: Receive using a batch job ....................................................... 16\nStep 5: Allocate target and distribution libraries ......................................... 16\nStep 6: Create DDDEF entries .................................................................... 16\nStep 7: Perform SMP/E apply .................................................................... 17\n Method 1: Apply using SMP/E dialogs ................................................... 17\n Method 2: Apply using a batch job ........................................................ 17\nStep 8: Run the installation verification program ......................................... 18\nStep 9: Perform SMP/E accept ................................................................. 18\n Method 1: Accept using SMP/E dialogs ............................................... 18\n Method 2: Accept using a batch job ....................................................... 18\nStep 10: Download Program Understanding Tool ......................................... 19\n\nStep 11: Define Interactive Debug Facility to VTAM ........................................ 19\n\nChapter 3. Maintaining HLASM Toolkit Feature on z/OS ........................................... 21\nRe-installing HLASM Toolkit Feature .......................................................... 21\nApplying service updates ........................................................................... 21\n What you receive ................................................................................... 21\n Checklist for applying service ............................................................... 21\n Step 1: Prepare to install service ............................................................ 22\n Step 2: Receive the service ..................................................................... 22\n Step 3: Accept applied service (optional) .............................................. 22\n Step 4: Apply the service ....................................................................... 22\n Step 5: Test the service ......................................................................... 22\n Step 6: Accept the service ..................................................................... 22\nStep 7: Service on Program Understanding Tool ........................................ 22\nRemoving HLASM Toolkit Feature ............................................................. 23\nReporting a problem with HLASM Toolkit Feature ...................................... 23\nObtaining service information ..................................................................... 23\n\n© Copyright IBM Corp. 1997, 2008\nChapter 1. Planning for installing HLASM Toolkit Feature on z/OS\n\nThis section contains the following planning information to help you properly install HLASM Toolkit Feature on z/OS:\n\n- Worksheet\n- What you receive with HLASM Toolkit Feature\n- What you need to install HLASM Toolkit Feature\n- Installing with CBPDO\n- Planning to use SMP/E\n- Planning to change installation jobs\n- Program support\n- Program and service level information\n- Publications useful during installation\n\nWorksheet: Planning for installing HLASM Toolkit Feature on z/OS\n\nBefore you begin the installation, you should:\n\n1. Verify the product parts to be installed.\n - FMID JMQ416A\n - Feature number 5822\n - VOLSER MQ416A\n Refer to “What you receive with HLASM Toolkit Feature” on page 4.\n\n2. Verify that required software (and optional software, if appropriate) is at the level needed.\n Refer to “What you need to install HLASM Toolkit Feature” on page 5.\n\n3. Verify that adequate DASD storage is available:\n - Target libraries\n - Distribution libraries\n - SMP/E data sets\n Refer to “DASD storage required for the target system” on page 6.\n\n4. Determine how you are going to use SMP/E:\n - Sample batch jobs\n - SMP/E dialogs\n Refer to “Planning to use SMP/E” on page 9.\n\n5. Plan for changes needed in installation jobs.\n Refer to “Planning to change installation jobs” on page 9.\n\n6. Obtain latest service updates needed.\n Refer to “Program support” on page 9\n\nWhat you receive with HLASM Toolkit Feature\n\nYou receive the following when you order HLASM Toolkit Feature for z/OS:\n\n<table>\n<thead>\n<tr>\n<th>FMID</th>\n<th>Feature Numbers</th>\n<th>System Name</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>JMQ416A</td>\n<td>5822</td>\n<td>z/OS</td>\n</tr>\n</tbody>\n</table>\n\nDistribution media\n\nHLASM Toolkit Feature is distributed on the following:\n- 3480 tape cartridge\n\nThe cartridge contains all the programs and data needed for installation. The cartridge is in SMP/E relative file format. The first file contains the SMP/E modification control statements. Subsequent files contain IEBCOPY, unloaded partitioned data sets, which SMP/E processes.\n\nBasic material\n\nTable 1 describes the cartridge; Table 2 describes the file content of the program cartridge.\n\nTable 1. Basic material: program cartridge\n\n<table>\n<thead>\n<tr>\n<th>Medium</th>\n<th>Feature Number</th>\n<th>Physical Volume</th>\n<th>External Label Identification</th>\n<th>VOLSER</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>3480 cart.</td>\n<td>5822</td>\n<td>1</td>\n<td>HLASM TLKT MVS R6</td>\n<td>MQ416A</td>\n</tr>\n</tbody>\n</table>\n\nTable 2. Program cartridge: file content\n\n<table>\n<thead>\n<tr>\n<th>Volser</th>\n<th>File</th>\n<th>Name</th>\n<th>ORG</th>\n<th>RECFM</th>\n<th>LRECL</th>\n<th>BLK SIZE</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>MQ416A</td>\n<td>1</td>\n<td>SMPMCS</td>\n<td>SEQ</td>\n<td>FB</td>\n<td>80</td>\n<td>6400</td>\n</tr>\n<tr>\n<td></td>\n<td>2</td>\n<td>IBM.JMQ416A.F1</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>8800</td>\n</tr>\n<tr>\n<td></td>\n<td>3</td>\n<td>IBM.JMQ416A.F2</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>8800</td>\n</tr>\n<tr>\n<td></td>\n<td>4</td>\n<td>IBM.JMQ416A.F3</td>\n<td>PDS</td>\n<td>U</td>\n<td>0</td>\n<td>6144</td>\n</tr>\n<tr>\n<td></td>\n<td>5</td>\n<td>IBM.JMQ416A.F4</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>8800</td>\n</tr>\n<tr>\n<td></td>\n<td>6</td>\n<td>IBM.JMQ416A.F5</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>8800</td>\n</tr>\n</tbody>\n</table>\n\nThe RECFM, LRECL, and BLK SIZE reflect the original values of the partitioned data sets (relative files) before being unloaded by the IEBCOPY utility to tape.\n\nNote: If you are installing HLASM Toolkit Feature using the MVS Custom-Built Product Delivery Offering (CBPDO) (5751-CS3), some of the information in these figures may not be valid. Consult the CBPDO documentation for actual values.\n\nOptional material\n\nThere are no optional machine-readable materials for HLASM Toolkit Feature.\n\nProgram publications and softcopy\n\nThis section identifies the basic and optional publications for HLASM Toolkit Feature.\nWhat you need to install HLASM Toolkit Feature\n\nThis section identifies the system requirements for installing HLASM Toolkit Feature. You need to plan for two different system environments:\n\n- **Target system**—the system comprising the set of libraries that are updated by SMP/E and system utilities during installation\n- **Driving system**—the system on which the jobs are run to install the program\n\nThe machine-readable components for HLASM Toolkit Feature are installed in target and distribution libraries.\n\n- **Target libraries** are the data sets in which the run-time copy of HLASM Toolkit Feature is stored. These data sets include the executable program code and any other components used during execution, such as sample JCL and messages.\n- **Distribution libraries** are the data sets in which additional copies of these components are stored. The copy of HLASM Toolkit Feature kept in the distribution libraries can be kept at a different service level than that in the target libraries. SMP/E can reconstruct the target libraries in whole or in part from the distribution libraries. Therefore, service or user modifications can be removed from the run-time copy of HLASM Toolkit Feature.\n\nIn many cases, the same system can be used as both a driving system and a target system. However, you may want to set up a clone of your system to use as a target system by making a separate IPL-able copy of the running system. The clone should include copies of all system libraries that SMP/E updates, copies of the SMP/E CSI data sets that describe the system libraries, and your PARMLIB and PROCLIB.\n\nSome cases where two systems should be used include the following:\n\n- When installing a new level of a product that is already installed, the new product will delete the old one. By installing onto a separate target system, you can test the new product while still keeping the old one in production.\n- When installing a product that shares libraries or load modules with other products, the installation can disrupt the other products. Installing onto a test system or clone will allow you to assess these impacts without disrupting your production system.\n\n**Required and optional software for the target system**\n\nThis section describes the other products that must be installed on the target system in order to install and use HLASM Toolkit Feature.\n\nHLASM Toolkit Feature runs on z/OS with the required licensed programs listed in Table 3 on page 6.\n\nYou should install the **minimum release listed or any subsequent release** for all required licensed programs your site needs.\nRequired and optional software for the target system\n\nTable 3. Required programs\n\n<table>\n<thead>\n<tr>\n<th>Required Licensed Program</th>\n<th>Minimum Version Supported</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>z/OS</td>\n<td>Version 1 Release 7</td>\n</tr>\n<tr>\n<td>SMP/E</td>\n<td>SMP/E for z/OS V3.4.0</td>\n</tr>\n<tr>\n<td>High Level Assembler</td>\n<td>Version 1 Release 6</td>\n</tr>\n</tbody>\n</table>\n\nNote: The IDF component of HLASM Toolkit Feature requires REXX™.\n\nCheck with the IBM Support Center for any PTFs you might need to apply.\n\nDASD storage required for the target system\n\nHLASM Toolkit Feature libraries can reside on any currently supported DASD.\n\nTable 4. Total DASD space required by HLASM Toolkit Feature\n\n<table>\n<thead>\n<tr>\n<th>Library Type</th>\n<th>Total Space Required</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Target</td>\n<td>303 Tracks</td>\n</tr>\n<tr>\n<td>Distribution</td>\n<td>351 Tracks</td>\n</tr>\n</tbody>\n</table>\n\nNotes:\n1. The data set sizes specified contain 15% extra space. You may wish to revise these numbers based on your plans for adding additional function or service.\n2. IBM recommends use of system determined blocksizes for efficient DASD utilization for all non-RECFM U data sets. For RECFM U data sets, IBM recommends a blocksize of 32760, which is the most efficient from a performance and DASD utilization perspective.\n If you choose not to use system determined blocksizes, use the blocksizes and numbers of blocks specified to allocate the data sets. Data sets can be reblocked to a larger size. Please note that the maximum allowable blocksize will depend on the type of DASD on which the dataset will reside; for example, the blocksize of datasets on a 3350 DASD cannot exceed 19,069.\n3. Abbreviations used for the data set type are:\n U Unique data set used by only the FMIDs listed. In order to determine the correct storage needed for this data set, this table provides all required information; no other tables (or program directories) need to be referenced for the data set size.\n S Shared data set used by more than the FMIDs listed. In order to determine the correct storage needed for this data set, the storage size given in this table needs to be added to other tables (perhaps in other program directories). If the data set already exists, it must have enough free space to accommodate the storage size given in this table.\n\nIf you currently have a previous release of this product installed in these libraries, the installation of this release will delete the old one and reclaim the space used by the old release and any service that had been installed. You can determine whether or not these libraries have enough space by deleting the old release with a dummy function, compressing the libraries, and comparing the space requirements with the free space in the libraries.\n\nFor more information on the names and sizes of the required data sets, please refer to Table 7 on page 7 and Table 8 on page 8.\nTable 5. Storage requirements for SMP/E work data sets\n\n<table>\n<thead>\n<tr>\n<th>Library DDNAME</th>\n<th>TYPE</th>\n<th>ORG</th>\n<th>REC</th>\n<th>LREC</th>\n<th>No. of 3390 Trks</th>\n<th>No. of DIR Blks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SMPWRK1</td>\n<td>S</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>30</td>\n<td>80</td>\n</tr>\n<tr>\n<td>SMPWRK2</td>\n<td>S</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>30</td>\n<td>80</td>\n</tr>\n<tr>\n<td>SMPWRK3</td>\n<td>S</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>180</td>\n<td>80</td>\n</tr>\n<tr>\n<td>SMPWRK4</td>\n<td>S</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>30</td>\n<td>80</td>\n</tr>\n<tr>\n<td>SMPWRK6</td>\n<td>S</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>30</td>\n<td>80</td>\n</tr>\n<tr>\n<td>SYSUT1</td>\n<td>U</td>\n<td>SEQ</td>\n<td>--</td>\n<td>--</td>\n<td>30</td>\n<td>0</td>\n</tr>\n<tr>\n<td>SYSUT2</td>\n<td>U</td>\n<td>SEQ</td>\n<td>--</td>\n<td>--</td>\n<td>30</td>\n<td>0</td>\n</tr>\n<tr>\n<td>SYSUT3</td>\n<td>U</td>\n<td>SEQ</td>\n<td>--</td>\n<td>--</td>\n<td>30</td>\n<td>0</td>\n</tr>\n<tr>\n<td>SYSUT4</td>\n<td>U</td>\n<td>SEQ</td>\n<td>--</td>\n<td>--</td>\n<td>30</td>\n<td>0</td>\n</tr>\n</tbody>\n</table>\n\nTable 5 provides an estimate of the storage needed in the SMP/E data sets for HLASM Toolkit Feature. The estimates must be added to those of any other programs and service being installed to determine the total additional storage requirements.\n\nTable 6. Storage requirements for SMP/E data sets\n\n<table>\n<thead>\n<tr>\n<th>Library DDNAME</th>\n<th>TYPE</th>\n<th>ORG</th>\n<th>REC</th>\n<th>LREC</th>\n<th>No. of 3390 Trks</th>\n<th>No. of DIR Blks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SMPMTS</td>\n<td>S</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>30</td>\n<td>5</td>\n</tr>\n<tr>\n<td>SMPPTS</td>\n<td>S</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>30</td>\n<td>5</td>\n</tr>\n<tr>\n<td>SMPSCDS</td>\n<td>S</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>30</td>\n<td>5</td>\n</tr>\n<tr>\n<td>SMPSTS</td>\n<td>S</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>30</td>\n<td>5</td>\n</tr>\n</tbody>\n</table>\n\nTable 6 and Table 8 on page 8 list the target and distribution libraries and their attributes required to install HLASM Toolkit Feature. The storage requirements of HLASM Toolkit Feature must be added to the storage required by other programs having data in the same library.\n\nTable 7. Storage requirements for HLASM Toolkit Feature target libraries\n\n<table>\n<thead>\n<tr>\n<th>Library DDNAME</th>\n<th>Member Type</th>\n<th>Target Volume</th>\n<th>TYPE</th>\n<th>ORG</th>\n<th>REC</th>\n<th>LREC</th>\n<th>No. of 3390 Trks</th>\n<th>No. of DIR Blks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SASMMOD2</td>\n<td>LMOD</td>\n<td>Any</td>\n<td>U</td>\n<td>PDS</td>\n<td>U</td>\n<td>0</td>\n<td>49</td>\n<td>2</td>\n</tr>\n<tr>\n<td>SASMSAM2</td>\n<td>EXEC SOURCE SAMPLE DATA PROC</td>\n<td>Any</td>\n<td>U</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>17</td>\n<td>1</td>\n</tr>\n<tr>\n<td>SASMMCAC2</td>\n<td>MACRO</td>\n<td>Any</td>\n<td>U</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>6</td>\n<td>1</td>\n</tr>\n</tbody>\n</table>\n\nChapter 1. Planning for installing HLASM Toolkit Feature on z/OS\nTable 7. Storage requirements for HLASM Toolkit Feature target libraries (continued)\n\n<table>\n<thead>\n<tr>\n<th>Library DDNAME</th>\n<th>Member Type</th>\n<th>Target Volume</th>\n<th>TYPE</th>\n<th>ORG</th>\n<th>REXEC</th>\n<th>LREC</th>\n<th>No. of 3390 Trks</th>\n<th>No. of DIR Blks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SASMPUT2</td>\n<td>DATA</td>\n<td>Any</td>\n<td>U</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>231</td>\n<td>1</td>\n</tr>\n</tbody>\n</table>\n\nTable 8. Storage requirements for HLASM Toolkit Feature distribution libraries\n\n<table>\n<thead>\n<tr>\n<th>Library DDNAME</th>\n<th>TYPE</th>\n<th>ORG</th>\n<th>REXEC</th>\n<th>LREC</th>\n<th>No. of 3390 Trks</th>\n<th>No. of DIR Blks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AASMMOD2</td>\n<td>U</td>\n<td>PDS</td>\n<td>U</td>\n<td>0</td>\n<td>97</td>\n<td>73</td>\n</tr>\n<tr>\n<td>AASMSAM2</td>\n<td>U</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>17</td>\n<td>1</td>\n</tr>\n<tr>\n<td>AASMMAC2</td>\n<td>U</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>6</td>\n<td>1</td>\n</tr>\n<tr>\n<td>AASMPUT2</td>\n<td>U</td>\n<td>PDS</td>\n<td>FB</td>\n<td>80</td>\n<td>231</td>\n<td>1</td>\n</tr>\n</tbody>\n</table>\n\nThe user may gain access to the supplied sample JCL after the SMP/E RECEIVE step in the install process. Alternatively, the user may copy the sample JCL directly from the installation tape into a temporary library. If this latter method is used then the dataset requirement is shown in the following table.\n\nTable 9. Storage requirements for temporary library\n\n<table>\n<thead>\n<tr>\n<th>Data Set Name</th>\n<th>TYPE</th>\n<th>ORG</th>\n<th>REXEC</th>\n<th>LREC</th>\n<th>No. of 3390 Trks</th>\n<th>No. of DIR Blks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>JCL</td>\n<td>U</td>\n<td>SEQ</td>\n<td>FB</td>\n<td>80</td>\n<td>40</td>\n<td>4</td>\n</tr>\n</tbody>\n</table>\n\nFMIDs deleted\n\nInstalling HLASM Toolkit Feature may result in the deletion of other FMIDs. To see what FMIDs will be deleted, examine the ++VER statement in the product’s SMPMCS.\n\nInstalling with CBPDO\n\nIf you are installing HLASM Toolkit Feature with an MVS Custom-Built Product Delivery Offering (CBPDO) (5751-CS3), use the RCVPDO job in the CBPDO RIMLIB data set provided with the CBPDO to receive the product and service for this product. Any additional installation instructions should be obtained from the HLASM Toolkit Feature documentation. However, before installing HLASM Toolkit Feature, check with your IBM Support Center or use either Information/Access or SoftwareXcel Extended to see whether there is additional service information you need.\nPlanning to use SMP/E\n\nYou must decide how to use SMP/E to install HLASM Toolkit Feature. Some points to consider are:\n\n1. This FMID must be installed in the same CSI as HMQ4160.\n2. Choose to use an existing global and new target and distribution zones.\n3. Choose to use existing global, target and distribution zones.\n\nPlanning to change installation jobs\n\nEach sample job has instructions on how it is to be modified, to meet the requirements and standards at your site. Refer to these standards as needed for determining the values for these parameters.\n\nProgram support\n\nThis section describes the IBM support available for HLASM Toolkit Feature.\n\nProgram services\n\nContact your IBM representative for specific information about available program services.\n\nPreventive Service Planning\n\nBefore installing HLASM Toolkit Feature, you should review the current Preventive Service Planning (PSP) information. If you obtained HLASM Toolkit Feature as part of a CBPDO, there is HOLDDATA and PSP information included on the CBPDO tape.\n\nIf you obtained HLASM Toolkit Feature on a product tape, or if the CBPDO is more than two weeks old when you install it, you should contact the IBM Support Center or use S/390® SoftwareXcel to obtain the current “PSP Bucket”.\n\nPSP Buckets are identified by UPGRADEs, which specify product levels, and SUBSETs, which specify the FMIDs for a product level. The UPGRADE and SUBSET values for HLASM Toolkit Feature for z/OS are:\n\n<table>\n<thead>\n<tr>\n<th>UPGRADE</th>\n<th>SUBSET</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>HLASM160</td>\n<td>JMQ416A</td>\n<td>HLASM Toolkit MVS</td>\n</tr>\n</tbody>\n</table>\n\nStatement of support procedures\n\nReport any difficulties you have using this program to your IBM Support Center. If an APAR is required, the Support Center will provide the address to which any needed documentation can be sent.\n\nTable 11 on page 10 identifies the component ID (COMPID) for HLASM Toolkit Feature for z/OS.\nTable 11. Component IDs\n\n<table>\n<thead>\n<tr>\n<th>FMID</th>\n<th>COMPID</th>\n<th>Component Name</th>\n<th>RETAIN® Release</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>JMQ416A</td>\n<td>569623401</td>\n<td>MVS HLA TOOLKIT FEATURE</td>\n<td>16A</td>\n</tr>\n</tbody>\n</table>\n\nProgram and service level information\n\nThis section identifies the program and any relevant service levels of HLASM Toolkit Feature. The program level refers to the APAR fixes incorporated into the program. The service level refers to the PTFs integrated. Information about the cumulative service tape is also provided.\n\nProgram level information\n\nA list of APAR fixes against previous releases of HLASM Toolkit Feature that have been incorporated into this release is shown in Appendix A, “HLASM Toolkit Feature Service,” on page 79.\n\nService level information\n\nNo PTFs against this release of HLASM Toolkit Feature have been incorporated into the product tape.\n\nCumulative service tape\n\nA cumulative service tape, containing PTFs not incorporated into this release, might be included with this program. Installation instructions for cumulative service tapes can be found in the SMP/E publications.\n\nIf you received this product as part of a CBPDO or a ProductPac®, PTFs not incorporated into this release are provided on the tape, and a separate cumulative service tape will not be provided.\n\nPublications useful during installation\n\nThe publications listed in Table 12 may be useful during the installation of HLASM Toolkit Feature.\n\nTable 12. z/OS Publications\n\n<table>\n<thead>\n<tr>\n<th>Publication Title</th>\n<th>Form Number</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>z/OS MVS Initialization and Tuning Guide</td>\n<td>SA22-7591</td>\n</tr>\n<tr>\n<td>z/OS MVS Initialization and Tuning Reference</td>\n<td>SA22-7592</td>\n</tr>\n<tr>\n<td>z/OS MVS JCL Reference</td>\n<td>SA22-7597</td>\n</tr>\n<tr>\n<td>z/OS Planning for Installation</td>\n<td>GA22-7504</td>\n</tr>\n<tr>\n<td>SMP/E Messages, Codes, and Diagnosis</td>\n<td>GA22-7770</td>\n</tr>\n<tr>\n<td>SMP/E Commands</td>\n<td>SA22-7771</td>\n</tr>\n<tr>\n<td>SMP/E Reference</td>\n<td>SA22-7772</td>\n</tr>\n<tr>\n<td>SMP/E User’s Guide</td>\n<td>SA22-7773</td>\n</tr>\n</tbody>\n</table>\nPlanning to install in the link pack area\n\nLoad modules that are not shipped with the RN attribute are not re-entrant, and therefore are not eligible for the LPA. They should not be copied to an LPA library or placed in an APF-authorized library.\n\nCurrently no HLASM Toolkit Feature load modules are re-entrant.\n\nToolkit product enablement\n\nYou must be licensed to use the HLASM Toolkit Feature, in which case the IFAPRDxx member of PARMLIB may need to be updated in one of the following ways:\n\n- If HLASM Toolkit Feature is licensed as a separate product, add this entry:\n\n ```\n PRODUCT OWNER ('IBM CORP')\n NAME('HL_LVL ASSEMBLER')\n ID(5696-234)\n VERSION(*) RELEASE(*) MOD(*)\n FEATURENAME('TOOLKIT DEBUGGER')\n STATE(ENABLED)\n ```\n\n- If HLASM Toolkit Feature is licensed as a feature of z/OS, refer to z/OS Planning for Installation for information about adding the entries to IFAPRDxx.\nToolkit product enablement\nChapter 2. Installing HLASM Toolkit Feature on z/OS\n\nThis chapter describes the installation method and the step-by-step procedures to install and to activate the functions of HLASM Toolkit Feature.\n\nPlease note the following:\n- HLASM Toolkit Feature must be installed into the same SMP/E environment as High Level Assembler.\n- Sample jobs have been provided to help perform some or all of the installation tasks. The SMP/E jobs assume that all DDDEF entries required for SMP/E execution have been defined in the appropriate zones.\n- The SMP/E dialogs may be used instead of the sample jobs to accomplish the SMP/E installation steps.\n\nOverview of installation\n\nYou install this release of HLASM Toolkit Feature by using the SMP/E RECEIVE, APPLY, and ACCEPT commands. This may be accomplished by using SMP/E dialogs or running batch jobs.\n\nModifying HLASM Toolkit Feature jobs\n\nThe installation jobs that IBM provides do not necessarily follow the conventions (such as file-naming conventions) for your site. You might need to modify them. Descriptions of possible modifications appear in the comments in the sample jobs.\n\nIf using a CBPDO\n\nIf you obtained HLASM Toolkit Feature as part of a CBPDO, you can use the RCVPDO job found in the CBPDO RIMLIB data set to RECEIVE the HLASM Toolkit Feature FMID as well as any service, HOLDDATA, or preventive service planning (PSP) information included on the CBPDO tape. For more information, refer to the documentation included with the CBPDO.\n\nInstallation checklist\n\nTable 13 lists the steps and associated jobs to install HLASM Toolkit Feature. The remaining sections in this chapter describe each step. You can use Table 13 as a checklist.\n\nTable 13. Summary of steps for installing HLASM Toolkit Feature\n\n<table>\n<thead>\n<tr>\n<th>Step</th>\n<th>Description</th>\n<th>Installation Job</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>_1</td>\n<td>SMP/E Considerations for Installing HLASM Toolkit Feature</td>\n<td>ASMWTCPY</td>\n<td>14</td>\n</tr>\n<tr>\n<td>_2</td>\n<td>Copy the sample JCL from the Product Tape</td>\n<td>ASMWTEDT</td>\n<td>15</td>\n</tr>\n<tr>\n<td>_3</td>\n<td>Set up ISPF Editor Macro (Optional)</td>\n<td>ASMWTALC</td>\n<td>16</td>\n</tr>\n<tr>\n<td>_4</td>\n<td>Perform SMP/E Receive</td>\n<td>ASMWTRCV</td>\n<td>15</td>\n</tr>\n<tr>\n<td>_5</td>\n<td>Allocate Target and Distribution Libraries</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>_6</td>\n<td>Create DDDEF Entries</td>\n<td>ASMWTDDF</td>\n<td>16</td>\n</tr>\n<tr>\n<td>_7</td>\n<td>Perform SMP/E Apply</td>\n<td>ASMWTAAPL</td>\n<td>17</td>\n</tr>\n</tbody>\n</table>\nStep 1: SMP/E considerations for installing HLASM Toolkit Feature\n\nThis release of HLASM Toolkit Feature is installed using the SMP/E RECEIVE, APPLY, and ACCEPT commands. The SMP/E dialogs may be used to accomplish the SMP/E installation steps.\n\nSMP/E environment\n\nAll SMP/E installation jobs provided assume that all necessary DD statements for the execution of SMP/E are defined using DDDEFs.\n\nSample jobs are provided on the installation tape to help you install HLASM Toolkit Feature. After the RECEIVE step has been completed, the sample jobs can be found in SMPTLIB: IBM.JMQ416A.F1. Make a copy of these jobs in your own library and modify them to use during the installation of HLASM Toolkit Feature. The sample jobs are:\n\n- ASMWTEDT Sample EDIT macro\n- ASMWTRCV Sample RECEIVE job\n- ASMWTLAC Sample job to allocate target and distribution libraries\n- ASMWTTDF Sample job to define HLASM Toolkit Feature DDDEFs\n- ASMWVTAPL Sample APPLY job\n- ASMWTVIP Sample install verification job\n- ASMWVACP Sample ACCEPT job\n\nIn the sample SMP/E jobs provided, the name of the SMP/E CSI is #globalcsi. The global zone name in the SMP/E CSI is GL0BAL. The distribution zone name is #dzone. The target zone name is #tzone. The sample jobs should be updated to reflect the CSI and zone names where you installed High Level Assembler.\n\nSMP/E options subentry values\n\nThe recommended values for some SMP/E CSI subentries are shown in Table 14. Use of values lower than these may result in failures in the installation process. DSSPACE is a subentry in the GLOBAL options entry. PEMAX is a subentry of the GENERAL entry in the GLOBAL options entry. Refer to the SMP/E manuals for instructions on updating the global zone.\n\n<table>\n<thead>\n<tr>\n<th>SUB-ENTRY</th>\n<th>Value</th>\n<th>Comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>DSSPACE</td>\n<td>(300,150,250)</td>\n<td>Space Allocation for SMPTLIB data sets</td>\n</tr>\n<tr>\n<td>PEMAX</td>\n<td>SMP/E default</td>\n<td>IBM recommends using the SMP/E default for PEMAX</td>\n</tr>\n</tbody>\n</table>\nStep 2: Copy the sample JCL from the product tape\n\nThis step can be bypassed if you plan to use the sample jobs from the SMPTLIB: IBM.JMQ416A.F1 after the Receive Step.\n\nThe following sample JCL will copy the HLASM Toolkit Feature jobs from the tape. Add a job card and modify the parameters in boldface to uppercase values to meet your site’s requirements before submitting.\n\n```\n//COPY EXEC PGM=IEBCOPY\n//SYSPRINT DD SYSOUT=A\n//IN DD DSN=IBM.JMQ416A.F1,UNIT=#tape,VOL=SER=MQ416A,\n// DISP=(OLD,KEEP),LABEL=(2,SL)\n//OUT DD DSN=#hlq.JCL,\n// DISP=(NEW,CATLG,DELETE),\n// RECFM=FB,LRECL=80,BLKSIZE=0,\n// SPACE=(8800,(40,2,4)),\n// UNIT=#unit,\n// VOL=SER=#dasdvol\n//SYSUT3 DD UNIT=SYSALLDA,SPACE=(CYL,(1,1))\n//SYSIN DD *\nCOPY INDD=IN,OUTDD=OUT\n```\n\n*Figure 1. Load installation jobs*\n\nIn this sample, #tape is the unit value matching the product cartridge, #hlq.JCL is the name of the data set where the sample jobs will reside, #dasdvol is the volume serial of the DASD device where the data set will reside, and #unit is the DASD unit type of the volume.\n\nThis job is also supplied as ASMWTCPY in SMPTLIB: IBM.JMQ416A.F1\n\n---\n\nStep 3: Set up ISPF editor macro (optional)\n\nTo aid you in making changes to the SMP/E installation jobs ASMWTACP, ASMWTALC, ASMWTAPL, ASMWTDDF, ASMWTIVP, and ASMWTRCV, an ISPF editor macro, called ASMWTEDT, is supplied and is copied to your output data set. This macro lets you substitute proper values for all of the required variables in those jobs, instead of making the changes repeatedly by hand.\n\nEdit macro ASMWTEDT and provide the proper values. Then copy it to any data set in your TSO logon procedure SYSEXEC concatenation. Consult the instructions in the macro for more information.\n\n---\n\nStep 4: Perform SMP/E receive\n\nThere are two methods of receiving HLASM Toolkit Feature:\n\n- The interactive capability of SMP/E described in “Method 1: Receive using SMP/E dialogs.”\n- The batch procedure described in “Method 2: Receive using a batch job” on page 16.\n\n**Method 1: Receive using SMP/E dialogs**\n\nSelect the Command Generation option from the SMP/E Primary Option menu.\nMethod 1: Receive using SMP/E dialogs\n\nSupply the following information as you progress through subsequent command generation panels for the RECEIVE command:\n\n<table>\n<thead>\n<tr>\n<th>Information</th>\n<th>Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Name of your CSI</td>\n<td></td>\n</tr>\n<tr>\n<td>Zone name</td>\n<td>Global</td>\n</tr>\n<tr>\n<td>HOLDDATA</td>\n<td>No</td>\n</tr>\n<tr>\n<td>All</td>\n<td>No</td>\n</tr>\n<tr>\n<td>Select</td>\n<td>Yes</td>\n</tr>\n<tr>\n<td>FMID you are installing</td>\n<td>JMQ416A</td>\n</tr>\n<tr>\n<td>Data set name</td>\n<td></td>\n</tr>\n<tr>\n<td>Volume serial</td>\n<td></td>\n</tr>\n<tr>\n<td>Unit</td>\n<td></td>\n</tr>\n<tr>\n<td>Label Type</td>\n<td></td>\n</tr>\n<tr>\n<td>File</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nExpected Return Codes and Messages: This should issue a return code of zero and no error messages.\n\nMethod 2: Receive using a batch job\n\nEdit and submit job ASMWTRCV to receive HLASM Toolkit Feature. Consult the instructions in the sample job for more information.\n\nNote: If you obtained HLASM Toolkit Feature as part of a CBPDO, you can use the RCVPDO job found in the CBPDO RIMLIB data set to RECEIVE the HLASM Toolkit Feature FMID as well as any service, HOLDDATA, or preventive service planning (PSP) information included on the CBPDO tape. For more information, refer to the documentation included with the CBPDO.\n\nExpected Return Codes and Messages: This job should issue a return code of zero and no error messages.\n\nStep 5: Allocate target and distribution libraries\n\nEdit and submit job ASMWTALEC to allocate the SMP/E target and distribution libraries for HLASM Toolkit Feature. Consult the instructions in the sample job for more information.\n\nExpected Return Codes and Messages: This job should issue a return code of zero and no error messages.\n\nStep 6: Create DDDEF entries\n\nEdit and submit job ASMWTTDDF to create DDDEF entries for the SMP/E target and distribution libraries for HLASM Toolkit Feature. Consult the instructions in the sample job for more information.\n\nExpected Return Codes and Messages: This job should issue a return code of zero and no error messages.\n\nAfter this job, the SYSLIB concatenation needs to be updated in the target and distribution zones.\nStep 6: Create DDDEF entries\n\n- SASMMAC2 and AASMMAC2 libraries need to be added to the SYSLIB concatenation in the target zone.\n- AASMMAC2 library needs to be added to the SYSLIB concatenation in the distribution zone.\n\nStep 7: Perform SMP/E apply\n\nThere are two methods of applying HLASM Toolkit Feature:\n\n- The interactive capability of SMP/E described in “Method 1: Apply using SMP/E dialogs.”\n- The batch procedure described in “Method 2: Apply using a batch job.”\n\nTo receive the full benefit of the SMP/E Causer SYSMOD Summary Report, do not bypass the following on the APPLY CHECK: PRE, ID, REQ, and IFREQ. This is because the SMP/E root cause analysis identifies the cause only of ERRORS and not of WARNINGS (SYSMODs that are bypassed are treated as warnings, not errors, by SMP/E).\n\nMethod 1: Apply using SMP/E dialogs\n\n1. Select the Command Generation option from the SMP/E Primary Option menu. You will be asked to supply some of the information above as you progress through subsequent command generation panels for APPLY.\n2. Perform an APPLY CHECK before the APPLY. Examine the output from the APPLY CHECK run.\n **Expected Return Codes and Messages:** This should issue a return code of zero and no error messages.\n3. If it shows no conflict, rerun the APPLY with CHECK=NO.\n **Expected Return Codes and Messages:** This should issue a return code of zero and no error messages.\n\nMethod 2: Apply using a batch job\n\n1. Perform an Apply with Check\n Use the sample job ASMWTAPL to apply HLASM Toolkit Feature.\n The installation job ASMWTAPL invokes SMP/E to apply HLASM Toolkit Feature. ASMWTAPL performs an APPLY with the CHECK option to check for possible conflicts in the target zone.\n Edit and submit sample job ASMWTAPL to perform an SMP/E APPLY CHECK. Consult the instructions in the sample job for more information.\n **Expected Return Codes and Messages:** This job should issue a return code of zero and no error messages.\n2. Perform an Apply\n Edit sample job ASMWTAPL to remove CHECK operand and resubmit.\n **Expected Return Codes and Messages:** This job should issue a return code of zero and no error messages.\nStep 8: Run the installation verification program\n\nA sample job, ASMWTIVP, is provided to verify that the product has installed correctly. This job carries out the following functions:\n- Assembles test sample ASMTSAMP\n- Link edits test sample ASMTSAMP\n- Disassembles test module ASMTSAMP\n- Create language extraction file\n\nEdit and submit sample job ASMWTIVP. Consult the instructions in the sample job for more information. ASMWTIVP uses TSO BATCH to carry out its functions.\n\nExpected Return Codes and Messages: This should issue a return code of zero and no error messages.\n\nStep 9: Perform SMP/E accept\n\nTo permanently install HLASM Toolkit Feature, use SMP/E ACCEPT processing. You should accept HLASM Toolkit Feature before you apply any user modifications or install any maintenance because the SMP/E RESTORE command restores HLASM Toolkit Feature only to the level of the last version you accept.\n\nTo receive the full benefit of the SMP/E Causer SYSMOD Summary Report, do not bypass the following on the ACCEPT CHECK: PRE, ID, REQ, and IFREQ. This is because the SMP/E root cause analysis identifies the cause only of ERRORS and not of WARNINGS (SYSMODs that are bypassed are treated as warnings, not errors, by SMP/E).\n\nThere are two methods of accepting HLASM Toolkit Feature:\n- The interactive capability of SMP/E described in “Method 1: Accept using SMP/E dialogs.”\n- The batch procedure described in “Method 2: Accept using a batch job.”\n\nMethod 1: Accept using SMP/E dialogs\n\n1. Select the Command Generation option from the SMP/E Primary Option menu. Supply the information requested as you progress through subsequent command generation panels for ACCEPT.\n2. Perform an ACCEPT CHECK before running the ACCEPT command. Examine the output from the ACCEPT CHECK run. <\n Expected Return Codes and Messages: This should issue a return code of zero and no error messages.\n3. Perform an ACCEPT.\n If the ACCEPT CHECK run shows no conflict, rerun the ACCEPT with CHECK=NO.\n Expected Return Codes and Messages: This should issue a return code of zero and no error messages.\n\nMethod 2: Accept using a batch job\n\n1. Perform an ACCEPT with CHECK\n The job ASMWTACP performs an ACCEPT with the CHECK option to check for possible conflicts in the distribution zone.\nMethod 2: Accept using a batch job\n\nEdit and submit sample job ASMWTACP to perform an SMP/E ACCEPT CHECK for HLASM Toolkit Feature. Consult the instructions in the sample job for more information.\n\n**Expected Return Codes and Messages:** This job should issue a return code of zero and no error messages.\n\n2. Perform an ACCEPT\n\nWhen this job is successful, rerun this job without the CHECK option.\n\nBefore using SMP/E to load new distribution libraries, it is recommended that you set the ACCJCLIN indicator in the distribution zone. This will cause entries produced from JCLIN to be saved in the distribution zone whenever a SYSMOD containing inline JCLIN is ACCEPTed. For more information on the ACCJCLIN indicator, see the description of inline JCLIN in [SMP/E Commands](#).\n\n**Note:** The GROUPEXTEND operand indicates that SMP/E accept all requisite SYSMODs. The requisite SYSMODS might be applicable to other functions.\n\n**Expected Return Codes and Messages:** This job should issue a return code of zero and no error messages.\n\n---\n\n### Step 10: Download Program Understanding Tool\n\nInstructions to download the Program Understanding Tool are contained in Appendix D, “Installing Program Understanding Tool on Windows,” on page 85.\n\n---\n\n### Step 11: Define Interactive Debug Facility to VTAM\n\nIf you plan to conduct IDF debugging via VTAM sessions with your terminals, you must define the minor node names for IDF to VTAM. A minor node is defined by using the following naming convention:\n\n- The first five characters must be ASMTL\n- The last three characters must be consecutive 3-digit numbers, starting with 001\n\nIDF uses the ASMTLnnn minor node names for internal processing. These names are not the terminal LU names that are specified by the user in the LUNAME invocation parameters.\n\nThe number of minor node names defined must be sufficient to allow for the maximum number of concurrent IDF users using VTAM terminal sessions. You can define up to 999 minor node names for IDF.\n\nTo place the statements into a new member, do the following:\n\n1. Create a new member in the VTAM definitions library (VTAMLST).\n\n2. Update the new member with the required definitions.\n\n3. Add the new member’s name to the VTAM start options configuration file, ATCCONxx.\n\nTo place the statements into an existing member, do the following:\n\n1. Select a member in the VTAM definitions library (VTAMLST) that contains the major node definitions.\n\n2. Update the selected member with the minor node name definitions (APPL statements) for IDF.\nStep 11: Define Interactive Debug Facility to VTAM\n\nFor example, the following statements define a major node and 10 minor node names, ASMTL001 to ASMTL010. These sample definitions can be placed into a new member or into an existing member in the VTAM definitions library (VTAMLST):\n\nASMAPPL VBUILD TYPE=APPL\nASMTL001 APPL AUTH=(PASS,ACQ),PARSESS=NO\nASMTL002 APPL AUTH=(PASS,ACQ),PARSESS=NO\nASMTL003 APPL AUTH=(PASS,ACQ),PARSESS=NO\nASMTL004 APPL AUTH=(PASS,ACQ),PARSESS=NO\nASMTL005 APPL AUTH=(PASS,ACQ),PARSESS=NO\nASMTL006 APPL AUTH=(PASS,ACQ),PARSESS=NO\nASMTL007 APPL AUTH=(PASS,ACQ),PARSESS=NO\nASMTL008 APPL AUTH=(PASS,ACQ),PARSESS=NO\nASMTL009 APPL AUTH=(PASS,ACQ),PARSESS=NO\nASMTL010 APPL AUTH=(PASS,ACQ),PARSESS=NO\nChapter 3. Maintaining HLASM Toolkit Feature on z/OS\n\nThis chapter describes how to re-install HLASM Toolkit Feature and how to apply service updates to HLASM Toolkit Feature. To use the maintenance procedures effectively, you should have already installed HLASM Toolkit Feature and any required products.\n\nIn addition, this chapter describes how to remove HLASM Toolkit Feature.\n\nRe-installing HLASM Toolkit Feature\n\nThe action required here depends on the circumstance. If you want to re-install HLASM Toolkit Feature and you did not use the SMP/E ACCEPT command then use an SMP/E APPLY REDO command. However, if you did use the SMP/E ACCEPT command, then the product should be deleted before installing again. For more information refer to \"Removing HLASM Toolkit Feature\" on page 23.\n\nApplying service updates\n\nYou might need to apply maintenance or service updates to HLASM Toolkit Feature periodically.\n\nWhat you receive\n\nIf you report a problem with HLASM Toolkit Feature to your IBM Support Center, you will receive a tape containing one or more APARs or PTFs that have been created to solve your problem.\n\nYou might also receive a list of pre-requisite APARs or PTFs, which should have been applied to your system before applying the current service. These prerequisite APARs or PTFs, might relate to HLASM Toolkit Feature or any other licensed product you have installed, including z/OS.\n\nTo help you understand the service process, the following overview familiarizes you with applying service for HLASM Toolkit Feature.\n\nChecklist for applying service\n\nTable 15 lists the steps and associated SMP/E commands for installing corrective service on HLASM Toolkit Feature. You can use Table 15 as a checklist.\n\n<table>\n<thead>\n<tr>\n<th>Step</th>\n<th>Description</th>\n<th>SMP/E Command</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>__1</td>\n<td>Prepare to install service.</td>\n<td>—</td>\n<td>22</td>\n</tr>\n<tr>\n<td>__2</td>\n<td>Receive service.</td>\n<td>RECEIVE</td>\n<td>22</td>\n</tr>\n<tr>\n<td>__3</td>\n<td>Accept previously applied service (optional).</td>\n<td>ACCEPT</td>\n<td>22</td>\n</tr>\n<tr>\n<td>__4</td>\n<td>Apply service.</td>\n<td>APPLY</td>\n<td>22</td>\n</tr>\n<tr>\n<td>__5</td>\n<td>Test service.</td>\n<td>—</td>\n<td>22</td>\n</tr>\n<tr>\n<td>__6</td>\n<td>Accept service.</td>\n<td>ACCEPT</td>\n<td>22</td>\n</tr>\n<tr>\n<td>__7</td>\n<td>Service on Program Understanding Tool.</td>\n<td>—</td>\n<td>22</td>\n</tr>\n</tbody>\n</table>\nStep 1: Prepare to install service\n\nBefore you start applying service:\n1. Create a backup copy of the current HLASM Toolkit Feature. Save this copy of HLASM Toolkit Feature until you have completed installing the service and you are confident that the service runs correctly.\n2. Research each service tape through the IBM Support Center for any errors and/or additional information. Note all errors on the tape that were reported by APARs and apply the applicable fixes.\n\nStep 2: Receive the service\n\nReceive the service using SMP/E RECEIVE command. This can be done from the SMP/E dialogs in ISPF or using a batch job.\n\nStep 3: Accept applied service (optional)\n\nAccept any service you applied earlier but did not accept, if you are satisfied that the earlier service is not causing problems in your installation. This can be done from the SMP/E dialogs in ISPF or using a batch job. Accepting the earlier service allows you to use the SMP/E RESTORE command to return to your current level if you encounter a problem with the service you are currently applying. This can be done from the SMP/E dialogs in ISPF or using a batch job.\n\nStep 4: Apply the service\n\nApply the service using SMP/E APPLY command. You should use the SMP/E APPLY command with the CHECK operand first. Check the output; if it shows no conflict, rerun the APPLY without the CHECK option. This can be done from the SMP/E dialogs in ISPF or using a batch job.\n\nStep 5: Test the service\n\nThoroughly test your updated HLASM Toolkit Feature. Run the installation verification program to ensure that the product functions properly. You can use the job, ASMWTIVP, from the target library ASM.SASMSAM2, to do this. Do not accept a service update until you are confident that it runs correctly.\n\nIn the event of a serious problem, you can restore the backup copy of HLASM Toolkit Feature.\n\nStep 6: Accept the service\n\nAccept the service using SMP/E ACCEPT command. You should use the SMP/E ACCEPT command with the CHECK operand first. Check the output; if it shows no conflict, rerun the ACCEPT without the CHECK option. This can be done from the SMP/E dialogs in ISPF or using a batch job.\n\nStep 7: Service on Program Understanding Tool\n\nService which has an impact on the Program Understanding Tool will be indicated in the cover letter supplied with the service. Once service has been applied then the Program Understanding Tool should be updated on the workstation. Refer to Appendix E, “Maintaining Program Understanding Tool on Windows,” on page 89 for information on how to do this.\nRemoving HLASM Toolkit Feature\n\nTo delete HLASM Toolkit Feature, you must:\n- Make sure no other products depend on it.\n- Use a dummy function SYSMOD to delete it.\n- Receive, apply and accept the dummy function, and run the UCLIN to delete the SYSMOD entries for the deleted function and the dummy function.\n\nEdit and submit job ASMTDEL0 to delete HLASM Toolkit Feature. Consult the instructions in the sample job for more information.\n\nExpected Return Codes and Messages: You receive message GIM39701W because the dummy function SYSMOD has no elements. The SMP/E RECEIVE command returns a return code of 4. If any USERMODs have been applied then the SMP/E APPLY command issues a GIM44502W message indicating USERMOD changes will be lost with a return code of 4. Both these warning messages can be ignored.\n\nThe target and distribution libraries can now be deleted. They are shown in Table 7 on page 7 and Table 8 on page 8.\n\nReporting a problem with HLASM Toolkit Feature\n\nTo assist with reporting any difficulties, refer to the diagnostic process as shown in the HLASM Installation and Customization Guide.\n\nReport any difficulties with this product to your IBM Support Center. If an APAR is required, the Support Center will provide the address to which any needed documentation can be sent.\n\nTable 16 identifies the component ID (COMP ID) for HLASM Toolkit Feature for z/OS.\n\n<table>\n<thead>\n<tr>\n<th>FMID</th>\n<th>COMP ID</th>\n<th>Component Name</th>\n<th>REL</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>JMQ416A</td>\n<td>569623401</td>\n<td>MVS HLA TOOLKIT FEATURE</td>\n<td>16A</td>\n</tr>\n</tbody>\n</table>\n\nObtaining service information\n\nPreventive Service Planning (PSP) information is continually updated as fixes are made available for problems. Check with your IBM Support Center or use either Information/Access or SoftwareXcel Extended to see whether there is additional PSP information you need. To obtain this information, specify the following UPGRADE and SUBSET values: HLASM160 and JMQ416A.\nPart 2. On z/VM: planning for, installing, and maintaining High Level Assembler Toolkit Feature\n\nChapter 4. Planning for installing HLASM Toolkit Feature on z/VM\nWorksheet: Planning for installing HLASM Toolkit Feature on z/VM ................................................................. 27\nWhat you receive with HLASM Toolkit Feature ................................................................. 27\nDistribution media ................................................................. 27\nBasic material ................................................................. 27\nOptional material ................................................................. 27\nCumulative service tape ................................................................. 27\nProgram publications and softcopy ................................................................. 27\nWhat you need to install HLASM Toolkit Feature ................................................................. 29\nOperating system requirements ................................................................. 29\nOther program product requirements ................................................................. 29\nVMSES/E considerations ................................................................. 29\nDASD storage required ................................................................. 29\nProgram support ................................................................. 30\nProgram services ................................................................. 30\nPreventive Service Planning ................................................................. 31\nStatement of support procedures ................................................................. 31\nProgram and service level information ................................................................. 31\nProgram level information ................................................................. 31\nService level information ................................................................. 31\nPublications useful during installation ................................................................. 31\n\nChapter 5. Installing HLASM Toolkit Feature on z/VM\nOverview of installation ................................................................. 33\nChecklist for installing HLASM Toolkit Feature ................................................................. 33\nStep 1: Prepare to install HLASM Toolkit Feature ................................................................. 33\nStep 2: Allocate resources for installing HLASM Toolkit Feature ................................................................. 35\nCommon instructions for allocating storage resources ................................................................. 35\nIf installing on a minidisk ................................................................. 36\nIf installing on a shared file system ................................................................. 36\nStep 3: Install HLASM Toolkit Feature ................................................................. 38\nStep 4: Verify the installation in a test environment ................................................................. 39\nStep 5: Put HLASM Toolkit Feature into production ................................................................. 40\nStep 6: Download Program Understanding Tool ................................................................. 42\n\nChapter 6. Maintaining HLASM Toolkit Feature on z/VM\nRe-installing HLASM Toolkit Feature ................................................................. 43\nApplying service updates ................................................................. 43\nWhat you receive ................................................................. 43\nChecklist for applying service ................................................................. 43\nStep 1: Prepare to install service ................................................................. 44\nStep 2: Clear the alternate APPLY disk ................................................................. 45\nStep 3: Receive the new service ................................................................. 46\nStep 4: Apply the new service ................................................................. 47\nStep 5: Reapply local service ................................................................. 47\nStep 6: Update build status table ................................................................. 48\nStep 7: Rebuild serviced parts (objects) ................................................................. 49\nStep 8: Verify the service ................................................................. 50\nStep 9: Place the service into production ................................................................. 50\nStep 10: Service on Program Understanding Tool ................................................................. 52\nRemoving HLASM Toolkit Feature ................................................................. 52\nReporting a problem with HLASM Toolkit Feature ................................................................. 52\nObtaining service information ................................................................. 52\n\n© Copyright IBM Corp. 1997, 2008\nChapter 4. Planning for installing HLASM Toolkit Feature on z/VM\n\nThis section contains the following planning information to help you properly install HLASM Toolkit Feature on VM:\n- Worksheet\n- What you receive with HLASM Toolkit Feature\n- Identifying required and optional software\n- VMSES/E considerations\n- Verifying that you have enough DASD storage\n- Program support\n- Program and service level information\n- Publications useful during installation\n\nWorksheet: Planning for installing HLASM Toolkit Feature on z/VM\n\nBefore you begin the installation you should:\n\n1. Determine which of the following you are installing HLASM Toolkit Feature as:\n - Part of a z/VM System Delivery Offering\n - By itself\n If installing HLASM Toolkit Feature by itself, determine the product parts to be installed:\n - COMPID 569623401\n - Feature number 5832\n See “What you receive with HLASM Toolkit Feature.”\n\n2. Verify that required software (and optional software, if appropriate) is at the level needed. See “What you need to install HLASM Toolkit Feature” on page 29.\n\n3. Ensure you are familiar with VMSES/E. See “VMSES/E considerations” on page 29.\n\n4. Verify that adequate storage is available:\n - Minidisks\n - Shared File System\n See “DASD storage required” on page 29.\n\n5. Obtain latest service updates needed. See “Program support” on page 30.\n\n\nWhat you receive with HLASM Toolkit Feature\n\nYou receive the following when you order HLASM Toolkit Feature:\n\n<table>\n<thead>\n<tr>\n<th>COMPIDs</th>\n<th>Feature Numbers</th>\n<th>System Name</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>569623401</td>\n<td>5832</td>\n<td>z/VM</td>\n</tr>\n</tbody>\n</table>\nWhat you receive with HLASM Toolkit Feature\n\nDistribution media\n\nHLASM Toolkit Feature is available through the z/VM SDO on 3590 and 3592 tape cartridge. You can also receive this program electronically by ordering it through the z/VM SDO using IBM ShopzSeries. For more information about IBM ShopzSeries go to www.ibm.com/software/ShopzSeries.\n\nThe tape cartridge or electronic envelope contains all the programs and data needed for installation.\n\nBasic material\n\nTable 17 describes the cartridge. Table 18 describes the file content of the program cartridge.\n\nTable 17. Basic material: program cartridge\n\n<table>\n<thead>\n<tr>\n<th>Medium</th>\n<th>Feature Number</th>\n<th>Physical Volume</th>\n<th>External Label Identification</th>\n<th>VOLSER</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>3480 cart.</td>\n<td>5832</td>\n<td>1</td>\n<td>HLASM TLKT VM R6</td>\n<td>unlabeled</td>\n</tr>\n</tbody>\n</table>\n\nTable 18. Program cartridge: file content\n\n<table>\n<thead>\n<tr>\n<th>File</th>\n<th>Content</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>Tape Header</td>\n</tr>\n<tr>\n<td>2</td>\n<td>Tape Header</td>\n</tr>\n<tr>\n<td>3</td>\n<td>Product Header</td>\n</tr>\n<tr>\n<td>4</td>\n<td>Product Memo</td>\n</tr>\n<tr>\n<td>5</td>\n<td>Service Apply Lists</td>\n</tr>\n<tr>\n<td>6</td>\n<td>PTFPARTS</td>\n</tr>\n<tr>\n<td>7</td>\n<td>HLASM Toolkit Feature Service</td>\n</tr>\n<tr>\n<td>8</td>\n<td>HLASM Toolkit Feature Service summary</td>\n</tr>\n<tr>\n<td>9</td>\n<td>HLASM Toolkit Feature Base code</td>\n</tr>\n<tr>\n<td>10</td>\n<td>HLASM Toolkit Feature Sample files</td>\n</tr>\n<tr>\n<td>11</td>\n<td>HLASM Toolkit Feature Executable product code</td>\n</tr>\n</tbody>\n</table>\n\nOptional material\n\nThere are no optional materials for HLASM Toolkit Feature.\n\nCumulative service tape\n\nYou might receive an additional tape containing cumulative service with your order. The PTFs on this tape have not yet been incorporated into this release.\n\nIf you received this product as part of a z/VM System Delivery Offering, PTFs that have not been incorporated into this release are provided on the tape. A separate cumulative service tape is not provided.\n\nProgram publications and softcopy\n\nThis section identifies the basic and optional publications for HLASM Toolkit Feature.\n\n- HLASM Licensed Program Specifications GC26-4944\nWhat you receive with HLASM Toolkit Feature\n\n- HLASM Toolkit Feature Installation and Customization Guide GC26-8711\n- HLASM Toolkit Feature Interactive Debug Facility User’s Guide GC26-8709\n- HLASM Toolkit Feature User’s Guide GC26-8710\n- HLASM Toolkit Feature Debug Reference Summary GC26-8712\n\nFor a list of books for related products, see “Bibliography” on page 91.\n\nWhat you need to install HLASM Toolkit Feature\n\nThe following sections identify the system requirements for installing HLASM Toolkit Feature.\n\nOperating system requirements\n\nHLASM Toolkit Feature supports the following z/VM operating systems and subsequent releases and versions:\n- z/VM Version 5\n\nOther program product requirements\n\n<table>\n<thead>\n<tr>\n<th>Required Licensed Program</th>\n<th>Minimum Version Supported</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>HIGH LEVEL ASSEMBLER for z/OS & z/VM & z/VSE</td>\n<td>Version 1 Release 6</td>\n</tr>\n</tbody>\n</table>\n\nNote: The IDF component of HLASM Toolkit Feature requires REXX.\n\nVMSES/E considerations\n\nThis section describes items that should be considered before you install HLASM Toolkit Feature.\n\n- VMSES/E is required to install and service this product.\n- If multiple users install and maintain licensed products on your system there might be a problem getting the necessary write access to MAINT’s 51D disk. If you find that there is contention for write access to the 51D disk, you can eliminate it by converting the software inventory from minidisk to the Shared File System (SFS). See z/VM: VMSES/E Introduction and Reference for information on how to make this change.\n- HLASM Toolkit Feature is installed and serviced using the user ID P696234K. IBM recommends that you use this userid, however, you can change the userid name if you wish. If you change this name, you must create a PPF override. Generally this section of this installation and customization guide assumes that you have used the IBM-recommended userid, P696234K.\n- If you plan to change the userid, it might be easier to do so during Step 1, substep 6 on page 34, while you are installing the product.\n\nDASD storage required\n\nBefore installing you need to understand the user ID and DASD storage requirements. They are shown in Table 20 on page 30. Some important points to consider are:\n\n- The installation user ID and minidisks or SFS are defined in “Step 2: Allocate resources for installing HLASM Toolkit Feature” on page 35. Table 20 on page 30 gives an estimate of the storage required to install HLASM Toolkit Feature.\nWhat you need to install HLASM Toolkit Feature\n\n- P696234K is the default user ID and can be changed. If you choose to change the name you need to create a Product Parameter File (PPF) override to change the name. This can be done in Step 1, substep 6 on page 34.\n- If you choose to install HLASM Toolkit Feature on a common user ID, the default minidisk addresses for HLASM Toolkit Feature might already be defined. If any of the default minidisks required by HLASM Toolkit Feature are already in use, create an override to change the minidisks for HLASM Toolkit Feature so they are unique.\n\nTable 20. DASD storage requirements for target minidisks\n\n<table>\n<thead>\n<tr>\n<th>Minidisk Owner (user ID)</th>\n<th>Default Address</th>\n<th>Storage in Cylinders</th>\n<th>SFS 4K Blocks</th>\n<th>Usage</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td>DASD CYLS</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>P696234K</td>\n<td>2B2</td>\n<td>3390 50</td>\n<td>9000</td>\n<td>Contains all the base code shipped with HLASM Toolkit Feature. VMSYS:P696234K.HLASMTL.OBJECT</td>\n</tr>\n<tr>\n<td>P696234K</td>\n<td>2C2</td>\n<td>3390 4</td>\n<td>720</td>\n<td>Contains a sample file VMSYS:P696234K.HLASMTL.LOCAL</td>\n</tr>\n<tr>\n<td>P696234K</td>\n<td>2D2</td>\n<td>3390 50</td>\n<td>9000</td>\n<td>Contains serviced files. VMSYS:P696234K.HLASMTL.DELTA</td>\n</tr>\n<tr>\n<td>P696234K</td>\n<td>2A6</td>\n<td>3390 1</td>\n<td>180</td>\n<td>Contains AUX files and software inventory files that represents your test service level of HLASM Toolkit Feature. VMSYS:P696234K.HLASMTL.APPLYALT</td>\n</tr>\n<tr>\n<td>P696234K</td>\n<td>2A2</td>\n<td>3390 1</td>\n<td>180</td>\n<td>Contains AUX files and software inventory files that represents the service level of HLASM Toolkit Feature that is currently in production. VMSYS:P696234K.HLASMTL.APPLYPROD</td>\n</tr>\n<tr>\n<td>P696234K</td>\n<td>29E</td>\n<td>3390 50</td>\n<td>9000</td>\n<td>Test build disk. This code is copied to a production disk, (for example, MAINT 19E ) so the production disk may also require this amount of free space. VMSYS:P696234K.HLASMTL.TBUILD</td>\n</tr>\n<tr>\n<td>P696234K</td>\n<td>191</td>\n<td>3390 5</td>\n<td>9000</td>\n<td>P696234K 191 minidisk. VMSYS:P696234K</td>\n</tr>\n</tbody>\n</table>\n\nNote: Cylinder values defined in this table are based on 4K block size.\n\nIf you plan to use SFS directories, then calculate the number of 4K blocks required from Table 20.\n\nProgram support\n\nThis section describes the IBM support available for HLASM Toolkit Feature.\n\nProgram services\n\nContact your IBM representative for specific information about available program services.\nPreventive Service Planning\n\nBefore installing HLASM Toolkit Feature, you should review the current Preventive Service Planning (PSP) information.\n\nPSP Buckets are identified by UPGRADEs, which specify product levels, and SUBSETs, which specify the FMIDs for a product level. The UPGRADE and SUBSET values for HLASM Toolkit Feature are:\n\nTable 21. PSP upgrade and subset ID\n\n<table>\n<thead>\n<tr>\n<th>UPGRADE</th>\n<th>SUBSET</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>HLASM160</td>\n<td>HLASMVM36A</td>\n<td>HLASM Toolkit VM</td>\n</tr>\n</tbody>\n</table>\n\nStatement of support procedures\n\nReport any difficulties you have using this program to your IBM Support Center. If an APAR is required, the Support Center will provide the address to which any needed documentation can be sent.\n\nTable 22. Component IDs\n\n<table>\n<thead>\n<tr>\n<th>COMPID</th>\n<th>Component Name</th>\n<th>RETAIN Release</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>569623401</td>\n<td>VM HLA TOOLKIT FEATURE</td>\n<td>36A</td>\n</tr>\n</tbody>\n</table>\n\nProgram and service level information\n\nThis section identifies the program and any relevant service levels of HLASM Toolkit Feature. The program level refers to the APAR fixes incorporated into the program. The service level refers to the PTFs integrated. Information about the cumulative service tape is also provided.\n\nProgram level information\n\nA list of APAR fixes against previous releases of HLASM Toolkit Feature that have been incorporated into this release is shown in Appendix A, “HLASM Toolkit Feature Service,” on page 79.\n\nService level information\n\nNo PTFs against this release of HLASM Toolkit Feature have been incorporated into the product tape.\n\nPublications useful during installation\n\nThe publications listed in Table 23 may be useful during the installation of HLASM Toolkit Feature for z/VM.\n\nTable 23. z/VM publications\n\n<table>\n<thead>\n<tr>\n<th>Publication Title</th>\n<th>Form Number</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>z/VM: VMSES/E Introduction and Reference</td>\n<td>GC24-6130</td>\n</tr>\n<tr>\n<td>z/VM: Service Guide</td>\n<td>GC24-6117</td>\n</tr>\n</tbody>\n</table>\n### Table 23. z/VM publications (continued)\n\n<table>\n<thead>\n<tr>\n<th>Publication Title</th>\n<th>Form Number</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>z/VM: CMS Commands and Utilities Reference</td>\n<td>SC24-6073</td>\n</tr>\n<tr>\n<td>z/VM: CMS File Pool Planning, Administration, and Operation</td>\n<td>SC24-6074</td>\n</tr>\n<tr>\n<td>z/VM: CP Planning and Administration</td>\n<td>SC24-6083</td>\n</tr>\n<tr>\n<td>z/VM: Saved Segments Planning and Administration</td>\n<td>SC24-6116</td>\n</tr>\n<tr>\n<td>z/VM: Other Components Messages and Codes</td>\n<td>GC24-6120</td>\n</tr>\n<tr>\n<td>z/VM: CMS and REXX/VM Messages and Codes</td>\n<td>GC24-6118</td>\n</tr>\n<tr>\n<td>z/VM: CP System Messages and Codes</td>\n<td>GC24-6119</td>\n</tr>\n</tbody>\n</table>\nChapter 5. Installing HLASM Toolkit Feature on z/VM\n\nThis chapter describes the installation method and the step-by-step procedures you use to install and activate the functions of HLASM Toolkit Feature.\n\nOverview of installation\n\nYou install this release of HLASM Toolkit Feature by using VMSES/E commands.\n\nChecklist for installing HLASM Toolkit Feature\n\nTable 24 lists the steps and associated VMSES/E commands for installing HLASM Toolkit Feature. The remaining sections in this chapter describe each step. You can use Table 24 as a checklist.\n\nTable 24. Summary of steps for installing HLASM Toolkit Feature\n\n<table>\n<thead>\n<tr>\n<th>Step</th>\n<th>Description</th>\n<th>VMSES/E Command</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>__ 1</td>\n<td>Prepare to install HLASM Toolkit Feature.</td>\n<td>VMFINS</td>\n<td>33</td>\n</tr>\n<tr>\n<td>__ 2</td>\n<td>Allocate resources for installing HLASM Toolkit Feature.</td>\n<td>VMFINS</td>\n<td>35</td>\n</tr>\n<tr>\n<td>__ 3</td>\n<td>Install HLASM Toolkit Feature.</td>\n<td>VMFINS</td>\n<td>38</td>\n</tr>\n<tr>\n<td>__ 4</td>\n<td>Verify the installation in a test environment.</td>\n<td>VMFINS</td>\n<td>39</td>\n</tr>\n<tr>\n<td>__ 5</td>\n<td>Place HLASM Toolkit Feature into production.</td>\n<td>VMFCOPY</td>\n<td>40</td>\n</tr>\n<tr>\n<td>__ 6</td>\n<td>Download Program Understanding Tool to workstation.</td>\n<td></td>\n<td>42</td>\n</tr>\n</tbody>\n</table>\n\nStep 1: Prepare to install HLASM Toolkit Feature\n\nCarry out the following preparatory tasks:\n\n1. Log on as the HLASM Toolkit Feature installer planner, typically the MAINT user ID. IBM recommends that you use P696234K as the product installation user ID.\n\n Normally, the MAINT user ID is used for the planning and setup for HLASM Toolkit Feature, then the P696234K user ID is used to install the product. However, you can log on as any user ID that has read access to MAINT's 5E5 minidisk and write access to the MAINT 51D minidisk.\n\n2. Make the installation media available.\n\n If you are installing from tape, attach the tape to the user ID at virtual address 181. Using virtual address 181 is required by the VMFINS EXEC.\n\n If you have received HLASM Toolkit Feature as an Envelope file, ensure the Envelope file exists on the A-disk, or any disk accessed as C.\n\n3. Establish read access to VMSES/E, using the following command:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>link MAINT 5e5 5e5 rr access 5e5 b</td>\n<td>Commands to access VMSES/E code.</td>\n</tr>\n</tbody>\n</table>\nStep 1: Prepare to install HLASM Toolkit Feature\n\n4. Establish write access to the software inventory disk.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>link MAINT 51d 51d mr access 51d d</td>\n<td>Commands to acquire write access to software inventory disk.</td>\n</tr>\n</tbody>\n</table>\n\nIf another user already has the software inventory disk linked in write mode (R/W), you are not allowed to link to that disk in write mode. The other user must relink to the software inventory disk in read-only mode, then you can try the above procedure again.\n\nThe VMSES/E system-level software inventory and other dependent files reside on the MAINT 51D disk.\n\nYou cannot proceed with the installation procedure until you have write access to the software inventory disk.\n\n5. Load the HLASM Toolkit Feature product control files onto the software inventory disk.\n\nIf you are installing from tape:\n\nCommand\n\nvmfins install info (nomemo)\n\nIf you are installing from an Envelope file:\n\nCommand\n\nvmfins install info (nomemo env filename)\n\nThis command will:\n\n- Load the Memo-to-Users file\n- Load the product control files including the Product Parameter File (PPF) and the PRODPART files\n- Create VMFINS PRODLIST on your A-disk. The VMFINS PRODLIST contains a list of products on the installation tape.\n\nOptions:\n\nfilename\n\nThe name of your Envelope file, for example, P696234K.\n\nnomemo\n\nLoads the memo but does not issue a prompt to send it to the system printer. Specify the memo option if you want to be prompted to print the memo.\n\n6. Obtain the resource planning information.\n\nIf you are installing from tape:\n\nCommand\n\nvmfins install ppf P696234K {HLASM|HLASMSFS} (plan nomemo)\n\nIf you are installing from an Envelope file:\n\nCommand\n\nvmfins install ppf P696234K {HLASM|HLASMSFS} (plan nomemo env filename)\n\nYou are prompted to change the installation defaults with message VMFINS2601R. Refer to the notes below for the changes you can make.\nStep 1: Prepare to install HLASM Toolkit Feature\n\nThis command creates the P696234K PLANINFO file on your A disk.\n- Use HLASM if HLASM Toolkit Feature is to be installed on a minidisk.\n- Use HLASMSFS if HLASM Toolkit Feature is to be installed in SFS.\n\nNote: This command does not load HLASM Toolkit Feature.\n\nOptions:\n\nfilename\nThe name of your Envelope file, for example, P696234K.\n\nnomemo\nLoads the memo but does not issue a prompt to send it to the system printer. Specify the memo option if you want to be prompted to print the memo.\n\nplan VMFINS performs requisite checking, plans system resources, and provides an opportunity to override the defaults in the product parameter file.\n\nNotes:\n\na. You can override:\n - The name of the product parameter file\n - The default user IDs\n - Minidisk/directory definitions\n\nb. If you change the PPF name, a default user ID, or other parameters via a PPF override, you must use your changed values instead of those indicated (when appropriate), throughout the rest of the installation instructions, as well as the instructions for servicing HLASM Toolkit Feature. For example, you must specify your PPF override file name instead of P696234K for certain VMSES/E commands.\n\nc. If you are not familiar with creating PPF overrides using VMFINS, refer to z/VM: VMSES/E Introduction and Reference before you continue. Also see Appendix B, “Create Product Parameter File (PPF) override (z/VM),” on page 81.\n\n7. Review the install message log file\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfview install</td>\n<td>View the install message log.</td>\n</tr>\n</tbody>\n</table>\n\nReview the install message log ($VMFINS $MSGLOG). If necessary, correct any problems before going on. For information about specific error messages, see z/VM: Other Components Messages and Codes.\n\nStep 2: Allocate resources for installing HLASM Toolkit Feature\n\nUse the information from the P696234K PLANINFO file to allocate storage resources for your installation.\n\nIn the planning chapter, you decided whether to install on minidisk or shared file system (SFS). See “DASD storage required” on page 29 for the relevant storage requirements.\n\nCommon instructions for allocating storage resources\n\n1. Obtain the user directory from the P696234K PLANINFO file.\n - User directory entries contain all of the links and privilege classes necessary for the P696234K user ID.\nCommon instructions for allocating storage resources\n\n- Use the directory entry in the PLANINFO as a model for input to your system directory.\n The user directory entry resides at the bottom of the PLANINFO file at the end of the resource requirements section.\n\n2. Add the P696234K directory to the system directory.\n Change the password for P696234K from xxxx to a valid password in accordance with the security guidelines at your site.\n\nMinidisk installers: Go to \"If installing on a minidisk.\"\n\nSFS installers: Go to \"If installing on a shared file system.\"\n\nIf installing on a minidisk\n\nAfter obtaining the user directory from the P696234K PLANINFO file:\n- Add the MDISK statements to the directory entry for P696234K.\n- Use Table 20 on page 30 in Chapter 4, “Planning for installing HLASM Toolkit Feature on z/VM” to obtain the minidisk requirements.\n- Place the new directory online using VM/Directory Maintenance (DIRMAINT) or an equivalent CP directory maintenance method.\n\nGo to “Step 3: Install HLASM Toolkit Feature” on page 38\n\nIf installing on a shared file system\n\nAfter completing the common steps above, proceed as follows:\n\n1. If you want to use an SFS directory as the work space for the P696234K top directory, include the following in the P696234K directory entry. This change requires the directory to be rebuilt and placed online.\n\n<table>\n<thead>\n<tr>\n<th>Directory Statement</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>IPL CMS PARM FILEPOOL VMSYS</td>\n<td>This directory statement allows automatic access to the P696234K's top directory as file mode A.</td>\n</tr>\n</tbody>\n</table>\n\n2. Place the new directory online using VM/Directory Maintenance (DIRMAINT) or an equivalent CP directory maintenance method.\n\n3. Use the number of 4K blocks calculated from Table 20 on page 30.\n - If you are installing all the default HLASM Toolkit Feature SFS directories, the block requirements are summarized in the table.\n - If you are selectively installing SFS directories, calculate the number of 4K blocks your installation requires by adding up the storage required by each of the directories you plan to install.\n\n4. From a user ID that is an administrator for the VMSYS filepool, issue the following command:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>enroll user P696234K vmsys: (blocks blocks)</td>\n</tr>\n</tbody>\n</table>\n\n This command enrolls the user P696234K in the VMSYS filepool. VMSYS is the default filepool.\n\nOptions:\n\n- blocks The number of 4K blocks that you calculated previously.\nIf installing on a shared file system\n\nThis makes available a top directory of VMSYS:P696234K. to the user.\n\n5. Compare your storage needs to the amount of storage available in the filepool.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>query filepool status vmsys:</td>\n<td>Command to get a list of directories in the filepool and the number of free blocks. VMSYS is the default filepool ID.</td>\n</tr>\n</tbody>\n</table>\n\nIf the number of free blocks is smaller than the number of blocks you need to install HLASM Toolkit Feature (which you calculated in step 3 on page 36 above), you need to add space to the filepool.\n\nFor instructions on adding space to a filepool, see z/VM: CMS File Pool Planning, Administration, and Operation.\n\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>set filepool vmsys:</td>\n<td>Commands to create subdirectories</td>\n</tr>\n<tr>\n<td>create directory dirid</td>\n<td>Options: dirid The name of the SFS directory you are creating. Examples of the command above include:</td>\n</tr>\n<tr>\n<td>create directory vmsys:P696234K.HLASMTL</td>\n<td></td>\n</tr>\n<tr>\n<td>create directory vmsys:P696234K.HLASMTL.object</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>A complete list of default HLASM Toolkit Feature SFS directories is provided in Table 20 on page 30. For information about the CREATE DIRECTORY command, see z/VM: CMS Commands and Utilities Reference.</td>\n</tr>\n<tr>\n<td></td>\n<td>There is no need to create the top directory (VMSYS:P696234K.) as this has been implicitly created by the ENROLL command.</td>\n</tr>\n</tbody>\n</table>\n\n7. Give the MAINT user ID READ authority to the general-use test build directory, using the GRANT AUTHORITY command.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>grant auth vmsys:P696234K.HLASMTL.TESTPROD to MAINT (read newread</td>\n<td>The GRANT command permits copying files to MAINT’s 19E production disk.</td>\n</tr>\n</tbody>\n</table>\n\nOptions:\n\nread Gives the user read authority on a file or directory.\n\nnewread Indicates that the users automatically receive read authority for any new files added to the directory.\n\nFor more information about the GRANT AUTHORITY command, see z/VM: CMS Commands and Utilities Reference.\n\nGo to “Step 3: Install HLASM Toolkit Feature” on page 38.\nStep 3: Install HLASM Toolkit Feature\n\n1. Log on to the installation user ID, P696234K.\n\n2. Format minidisks\n If minidisks are to be used rather than SFS directories, then format these disks now. For a list of disk addresses, refer to Table 20 on page 30.\n\n3. Create or modify the PROFILE EXEC with ACCESS commands for MAINT’s 5E5 and 5ID disks. To do this, insert the following statements into the PROFILE EXEC:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'access 5e5 b'</td>\n<td>Statements to access the 5E5 disk.</td>\n</tr>\n<tr>\n<td>'access 51d d'</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n4. Execute the profile to access MAINT’s minidisks.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>profile</td>\n<td>Command to execute profile.</td>\n</tr>\n</tbody>\n</table>\n\n5. Verify that you have write access to the software inventory disk.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>q 51d</td>\n<td>Command to query access status of the software inventory disk.</td>\n</tr>\n</tbody>\n</table>\n\nIf the disk is not in read write mode (R/W) then see Step 1, substep 4 on page 34.\n\n6. Make installation media available:\n If you have received HLASM Toolkit Feature as a product tape, then attach the tape to the user ID at virtual address 181. Using virtual address 181 is required by the VMFINS EXEC.\n If you have received HLASM Toolkit Feature as an Envelope file, ensure the Envelope file exists on the A-disk.\n\n7. Install HLASM Toolkit Feature product from tape or from the envelope file.\n You might be prompted for additional information during VMFINS INSTALL processing, depending on your installation environment. If you are unsure how to respond to a prompt, refer to the appropriate sections in z/VM: VMSES/E Introduction and Reference.\n If you are installing from tape:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfins install pff P696234K {HLASM</td>\n</tr>\n</tbody>\n</table>\n\nIf you are installing from an Envelope file:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfins install pff P696234K {HLASM</td>\n</tr>\n</tbody>\n</table>\n\nThis command installs HLASM Toolkit Feature.\n- Use HLASM if HLASM Toolkit Feature is installed on a minidisk.\n- Use HLASMSFS if HLASM Toolkit Feature is installed in SFS.\nStep 3: Install HLASM Toolkit Feature\n\nYou are prompted to create an override for HLASM Toolkit Feature when this command executes. Refer to the message text for your response.\n\nOptions:\n\nnomemo\n\nLoads the memo but does not issue a prompt to send it to the system printer. Specify the memo option if you want to be prompted to print the memo.\n\nnolink\n\nIndicates that VMFINS is not to link to the appropriate minidisks, only access them if they are not already accessed.\n\nNotes:\n\na. You can override:\n • The name of the product parameter file\n • The default user IDs\n • Minidisk/directory definitions\n\nb. If you change the PPF name, a default user ID, or other parameters via a PPF override, you must use your changed values instead of those indicated (when appropriate), throughout the rest of the installation instructions, as well as the instructions for servicing HLASM Toolkit Feature. For example, you must specify your PPF override file name instead of P696234K for certain VMSES/E commands.\n\nc. If you are not familiar with creating PPF overrides using VMFINS, refer to z/VM: VMSES/E Introduction and Reference before you continue. Also see Appendix B, “Create Product Parameter File (PPF) override (z/VM),” on page 81.\n\n8. Review the install message log ($VMFINS $MSGLOG).\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfview install</td>\n<td>View the install message log.</td>\n</tr>\n</tbody>\n</table>\n\nCorrect any problems before you go on. For information about specific error messages, see z/VM: Other Components Messages and Codes.\n\nStep 4: Verify the installation in a test environment\n\n1. Update Build Status Table\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfins build ppf P696234K</td>\n<td>Update VM SYSBLDS software inventory file for HLASM Toolkit Feature.</td>\n</tr>\n<tr>\n<td>{HLASM</td>\n<td>HLASMSFS} (serviced nolink)</td>\n</tr>\n<tr>\n<td></td>\n<td>Use HLASMSFS if HLASM Toolkit Feature is installed in SFS.</td>\n</tr>\n</tbody>\n</table>\n\nOptions:\n\nserviced\n\nIdentifies build requirements and builds those objects flagged as serviced in the service-level build status table.\nStep 4: Verify the installation in a test environment\n\nIndicates that VMFINS is not to link to the appropriate minidisks, only to access them if they are not already accessed.\n\nYou may receive message VMFINB2173I, indicating that no verification EXEC is found for this product. This message is informational, and can be ignored from this invocation of the VMFBLD EXEC. The next substep manually invokes the verification process.\n\n2. Verify Installation\n\nPrior to running this verification, this userid must be able to access the High Level Assembler.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>T5696234</td>\n<td>This EXEC verifies the operation of the Disassembler and the Interactive Debug Facility.</td>\n</tr>\n</tbody>\n</table>\n\nThis verification test is run to ensure that HLASM Toolkit Feature was installed successfully. Figure 2 shows sample screen output from the verification process.\n\n---\n\nIBM HIGH LEVEL ASSEMBLER TOOLKIT FEATURE DISASSEMBLER\nVerification\n\nDisassembly of ASMTSAMP module completed successfully\nThe disassembly listing can be found in ASMTSAMP LISTING\n\n---\n\nIBM HIGH LEVEL ASSEMBLER TOOLKIT FEATURE Interactive Debug Facility Verification\n\nInteractive Debug Facility completed successfully.\nThe toolkit is installed successfully.\n\nReady; T=0.10/0.18 10:53:01\n\nFigure 2. Sample install verification output\n\nStep 5: Put HLASM Toolkit Feature into production\n\n1. Log on to MAINT if you plan to put HLASM Toolkit Feature general-use code on the 'Y' disk (MAINT's 19E disk). Alternatively, log on to the owner of the disk that is to contain the production level of the HLASM Toolkit Feature code.\n\n2. Link to HLASM Toolkit Feature code and access MAINT's Y disk.\n\nChoose which access is required depending on whether you have used a minidisk or SFS.\n\nFor minidisk access:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>link P696234K 29e 29e rr access 29e e</td>\n<td>Access HLASM Toolkit Feature code on a minidisk.</td>\n</tr>\n<tr>\n<td>access 19e f</td>\n<td>Access CMS's Y disk.</td>\n</tr>\n</tbody>\n</table>\n\n40 HLASM V1R6 Toolkit Feature Installation Guide\nStep 5: Put HLASM Toolkit Feature into production\n\nFor SFS access:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>access vmsys:P696234K.HLASMTL.TESTPROD e</td>\n<td>Access HLASM Toolkit Feature code in an SFS directory.</td>\n</tr>\n<tr>\n<td>access 19e f</td>\n<td>Access CMS’s Y disk.</td>\n</tr>\n</tbody>\n</table>\n\n3. Move HLASM Toolkit Feature to the Y disk.\n All the HLASM Toolkit Feature modules should be placed onto the Y disk using the VMFCOPY command.\n The ASMSMAC MACLIB should also be copied, if you wish to make the structured macros available to the users.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfcopy * MODULE e = = f2 (prodid P696234K%HLASM olddate replace</td>\n<td>Copy Toolkit to CMS’s Y disk.</td>\n</tr>\n<tr>\n<td>vmfcopy * MACLIB e = = f2 (prodid P696234K%HLASM olddate replace</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nOptions:\n\n- **olddate**\n Uses the date and time on each input file as the date and time of the last update of each corresponding output file.\n\n- **replace**\n Causes the output file to replace an existing file with the same file identifier.\n\nIf you do not want to use the Y disk for general use code, log on as the owner of the disk where you put the production level of the HLASM Toolkit Feature code.\n\nThe VMFCOPY command updates the VMSES PARTCAT file on the 19E disk.\n\nIf you want to move the Enhanced SuperC (SuperC) then the following parts should also be copied to the Y disk:\n- ASMSRCH OPTSLIST\n- ASMF3270 IOS3270\n- ASMF327 XMOD\n- ASMF327 EXEC\n- ASFSUPC NAMES\n- ASFSUPC MENU\n- ASFSUPC EXEC\n- ASFSUPC OPTSLIST\n- ASFSUPC HELP\n\nIf you want to move the cross reference facility (ASMXREF) then the following parts should also be copied to the Y disk:\n- ASMTST CNTL\n- ASMTST DEFAULTS\n- ASMTST EXEC\n- ASMTST ASSEMBLE\nStep 5: Put HLASM Toolkit Feature into production\n\n- ASMXRPT EXEC\n- ASMXSCAN EXEC\n- ASMXSEP EXEC\n- ASMXLANG SAMPLE\n- ASMXTOKN SAMPLE\n\n4. Resave the CMS saved system.\n This updates the shared Y-STAT (the saved Y disk file directory).\n a. Define named saved system\n This creates a named saved system for CMS.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfsetup zvm cms</td>\n<td>On z/VM, allows access to the SAMPNSS EXEC which resides on MAINT's 193 disk.</td>\n</tr>\n<tr>\n<td>sampnss cms</td>\n<td>Create named saved system for CMS.</td>\n</tr>\n</tbody>\n</table>\n\nb. Resave the CMS system\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1pl 190 clear parm savesys cms</td>\n<td>Resave CMS saved system to reflect the change to the Y-STAT (the saved Y disk file directory).</td>\n</tr>\n</tbody>\n</table>\n\nStep 6: Download Program Understanding Tool\n\nInstructions to download the Program Understanding Tool are contained in Appendix D, “Installing Program Understanding Tool on Windows,” on page 85.\n\nThis completes the installation process.\nChapter 6. Maintaining HLASM Toolkit Feature on z/VM\n\nThis chapter describes how to re-install, or remove HLASM Toolkit Feature and how to apply service updates. To effectively use the maintenance procedures, you must have already installed HLASM Toolkit Feature and any required products.\n\nTo become more familiar with service using VMSES/E, refer to z/VM: VMSES/E Introduction and Reference. This manual also contains the command syntax for the VMSES/E commands listed in the procedure.\n\nEach step of the service instructions must be followed; do not skip any step unless otherwise directed. All instructions showing accessing of disks assume default minidisk addresses. If different minidisk addresses are used, or if using a shared-file system, change the instructions appropriately.\n\nRe-installing HLASM Toolkit Feature\n\nYou should delete the product and commence the installation process from the beginning. To delete the product refer to \"Removing HLASM Toolkit Feature\" on page 52. When the product is deleted, start the installation from \"Step 1: Prepare to install HLASM Toolkit Feature\" on page 33.\n\nApplying service updates\n\nThis section describes how to apply maintenance or service updates to HLASM Toolkit Feature.\n\nWhat you receive\n\nIf you report a problem with HLASM Toolkit Feature to your IBM Support Center, you will receive a tape containing one or more APARs or PTFs which solve your problem.\n\nYou might also receive a list of pre-requisite APARs or PTFs, which should have been applied to your system before applying the current service. These pre-requisite APARs or PTFs might relate to HLASM Toolkit Feature or any other licensed product you have installed, including z/VM.\n\nThe following overview familiarizes you with some of the aspects of applying service for HLASM Toolkit Feature.\n\nChecklist for applying service\n\nTable 25 lists the steps and associated VMSES/E commands for installing corrective service on HLASM Toolkit Feature. You can use Table 25 as a checklist.\n\n<table>\n<thead>\n<tr>\n<th>Step</th>\n<th>Description</th>\n<th>VMSES/E Command</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><em>1</em></td>\n<td>Prepare to install service.</td>\n<td></td>\n<td>44</td>\n</tr>\n<tr>\n<td><em>2</em></td>\n<td>Clear the alternate APPLY disk. Doing this allows you to remove the new service easily later if necessary.</td>\n<td>VMFMRDSK</td>\n<td>45</td>\n</tr>\n</tbody>\n</table>\n## Table 25. Summary of steps for installing service on HLASM Toolkit Feature (continued)\n\n<table>\n<thead>\n<tr>\n<th>Step</th>\n<th>Description</th>\n<th>VMSES/E Command</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>__3</td>\n<td>Receive the new service.</td>\n<td>VMFREC</td>\n<td>46</td>\n</tr>\n<tr>\n<td>__4</td>\n<td>Apply the new service.</td>\n<td>VMFAPPLY</td>\n<td>47</td>\n</tr>\n<tr>\n<td>__5</td>\n<td>Reapply local service by entering local service into the software inventory (if applicable).</td>\n<td></td>\n<td>47</td>\n</tr>\n<tr>\n<td>__6</td>\n<td>Update Build Status Table.</td>\n<td>VMFBLD</td>\n<td>48</td>\n</tr>\n<tr>\n<td>__7</td>\n<td>Rebuild Serviced Parts (objects).</td>\n<td>VMFBLD</td>\n<td>49</td>\n</tr>\n<tr>\n<td>__8</td>\n<td>Verify the service that has been applied and built.</td>\n<td></td>\n<td>50</td>\n</tr>\n<tr>\n<td>__9</td>\n<td>Place into production</td>\n<td></td>\n<td>50</td>\n</tr>\n<tr>\n<td>__10</td>\n<td>Service on Program Understanding Tool</td>\n<td></td>\n<td>52</td>\n</tr>\n</tbody>\n</table>\n\n### Step 1: Prepare to install service\n\nCarry out preliminary steps prior to receiving service.\n\n#### Electronic Service (envelope file)\n\nIf you have received the service electronically or on CD-ROM, follow the appropriate instructions to retrieve and decompress the envelope files to your A-disk. The decompression is currently done by using the DETERSE MODULE (shipped with VMSES/E).\n\nThe documentation envelope and the service envelope files must have a file type of SERVLINK. Make note of the file names that you are using as you will need to enter them in place of the variable `envfilename` in the VMFREC commands that follow.\n\n1. Create a backup copy of the current HLASM Toolkit Feature before applying the service tape. Save this copy of HLASM Toolkit Feature until you have completed installing the service and you are confident that the service runs correctly.\n2. Log on to the HLASM Toolkit Feature service user ID: P696234K.\n3. Establish read-write (R/W) access to the software inventory disk.\n\n#### Command | Explanation\n---|---\n`link MAINT 51d 51d mr access 51d d` | Commands to access the software inventory disk.\n\n4. Mount the HLASM Toolkit Feature corrective service tape and verify that it is attached to user ID P696234K. Use an address of 181. (If you have a SERVLINK file make sure that it is available on the A-disk.)\n5. Establish the correct minidisk access order.\n\nThe VMFSETUP command accesses all the required disks or SFS directories to establish the needed file modes.\n\n#### Command | Explanation\n---|---\n`vmfsetup P696234K {HLASM|HLASMSFS}` |\nStep 1: Prepare to install service\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>P696234K</td>\n<td>The PPF that is shipped with HLASM Toolkit Feature. If you have your own PPF override, substitute your PPF name for P696234K.</td>\n</tr>\n<tr>\n<td>Use HLASM if HLASM Toolkit Feature is installed on minidisk. Use HLASMSFS if HLASM Toolkit Feature is installed in SFS.</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n6. Receive Documentation. VMFREC with the INFO option loads the documentation and displays a list of all the products on the tape.\n a. If receiving the service from tape\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfrec info</td>\n<td>The info option loads the documentation (including the product service memo) to the 191 disk and displays a list of products on the tape.</td>\n</tr>\n</tbody>\n</table>\n\n b. If receiving the service from an envelope file\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfrec info (env envfilename)</td>\n<td>The info option loads the documentation (including the product service memo) to the 191 disk and displays a list of products. envfilename is the file name of the documentation envelope (SERVLINK) file.</td>\n</tr>\n</tbody>\n</table>\n\n7. Check the receive message log ($VMFREC $MSGLOG) for attention and error messages.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfview receive</td>\n<td>View the receive message log</td>\n</tr>\n</tbody>\n</table>\n\n Make a note of which products and components have service on the tape. Press PF5 key to show all the status messages that identify the products on the tape.\n\nStep 2: Clear the alternate APPLY disk\n\nClear the alternate APPLY disk to ensure that you have a clean disk for new service.\n\n1. Clear disk\n\n Merge previously applied service to ensure that you have a clean alternate APPLY disk for new service.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfmrdsk P696234K {HLASM</td>\n<td>HLASMSFS} apply</td>\n</tr>\n</tbody>\n</table>\n### Step 2: Clear the alternate APPLY disk\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Command to clear the alternate APPLY disk. Use HLASM if HLASM Toolkit Feature is installed on minidisk. Use HLASMSFS if HLASM Toolkit Feature is installed in SFS.</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n### 2. Check merge message log\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfview mrd</td>\n<td>Command to review the merge message log ($VMFMRD $MSGLOG). Correct any problems before you go on. For information about specific error messages, refer to <a href=\"#\">z/VM: Other Components Messages and Codes</a>.</td>\n</tr>\n</tbody>\n</table>\n\n### Step 3: Receive the new service\n\n#### 1. Receive new service\n\n**Note:** If you are installing multiple service tapes, you can receive all the service for this product before applying and building it. For each service tape or electronic envelope you want to receive, do the following:\n\na. If receiving the service from tape:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfrec pff P696234K (HLASM</td>\n<td>HLASMSFS)</td>\n</tr>\n</tbody>\n</table>\n\nb. If receiving the service from the PTF envelope file:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfrec pff P696234K (HLASM</td>\n<td>HLASMSFS) (env enuflename</td>\n</tr>\n</tbody>\n</table>\n2. Review receive message log\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfview receive</td>\n<td>Command to review the receive message log ($VMFREC $MSGLOG). Correct any</td>\n</tr>\n<tr>\n<td></td>\n<td>problems before you go on. For information about specific error messages,</td>\n</tr>\n<tr>\n<td></td>\n<td>refer to z/VM: Other Components Messages and Codes.</td>\n</tr>\n</tbody>\n</table>\n\n**Step 4: Apply the new service**\n\n1. Apply the new service\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfapply ppf P696234K {HLASM</td>\n<td>HLASMSFS}</td>\n</tr>\n</tbody>\n</table>\n\n2. Review apply message log\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfview apply</td>\n<td>Command to review the apply message log ($VMFAPP $MSGLOG). Correct any</td>\n</tr>\n<tr>\n<td></td>\n<td>problems before going on. For information about specific error messages,</td>\n</tr>\n<tr>\n<td></td>\n<td>refer to z/VM: Other Components Messages and Codes.</td>\n</tr>\n</tbody>\n</table>\n\n**Step 5: Reapply local service**\n\nDo this step only if you received message VMFAPP2120W during the VMFAPPLY step.\n\n1. Reapply any local modifications before building the serviced HLASM Toolkit Feature. For further information, see z/VM Service Guide.\n\n2. If you are following the process in z/VM Service Guide, follow the steps that are applicable to your local modification. Then return to this Installation and Customization Guide to continue with “Step 6: Update build status table” on page 48.\n\n3. For the process in the z/VM Service Guide make the following substitutions:\n - zvm should be P696234K\n - compname should be HLASM or HLASMSFS (minidisk or SFS)\n - appid should be P696234K\n - fm-local should be the file mode of disk 2C2\n - fm-applyalt should be the file mode of disk 2A6\nStep 5: Reapply local service\n\n- if necessary, substitute your PPF override in all commands requiring the PPF name.\n\nStep 6: Update build status table\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfbld ppf P696234K {HLASM</td>\n<td>HLASMSFS} {status}</td>\n</tr>\n<tr>\n<td></td>\n<td>Use HLASM if HLASM Toolkit Feature is installed on minidisk.</td>\n</tr>\n<tr>\n<td></td>\n<td>Use HLASMSFS if HLASM Toolkit Feature is installed in SFS.</td>\n</tr>\n</tbody>\n</table>\n\nOptions:\n\nstatus Identifies build requirements.\n\nIf service has been applied to the source product parameter file (file type of $PPF), then carry out the instructions below before continuing on to “Step 7: Rebuild serviced parts (objects)” on page 49.\n\nIf the $PPF files have been serviced the following prompt is displayed:\n\nVMFBLD2185R The following source product parameter files have been serviced.\nVMFBLD2185R P696234K $PPF\nVMFBLD2185R When source product parameter files are serviced, all product parameter files built from them must be recompiled using VMFPFPF before VMFBLD can be run.\nVMFBLD2185R Enter zero (0) to have the serviced source product parameter files built to your A-disk and exit VMFBLD so you can recompile your product parameter files with VMFPFPF.\nVMFBLD2185R Enter one (1) to continue only if you have already recompiled your product parameter files with VMFPFPF.\n\nIf you select 0, then the following recompiles the product parameter files (PPF).\n\nYou should only select 1 if you have previously compiled your product parameter files. In this case, go to “Step 7: Rebuild serviced parts (objects)” on page 49.\n\n1. Indicate $PPF file needs to be compiled\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>Enter a 0 and continue with the following commands.</td>\n</tr>\n</tbody>\n</table>\n\nThe message\n\nVMFBLD2188I Building P696234K $PPF on 191 (A) from level $PFNnnnnn\n\nis displayed.\n\n2. Compile the product parameter file\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfppf P696234K *</td>\n<td>If you have your own PPF override, use your PPF name instead of P696234K.</td>\n</tr>\n</tbody>\n</table>\n3. Copy the product parameter file to software inventory disk\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>copyfile P696234K $PPF a = d (olddate replace)</td>\n<td>Do not use your own PPF name in place of P696234K for this COPYFILE command.</td>\n</tr>\n</tbody>\n</table>\n\n**Options:**\n\n- **olddate**\n Uses the date and time on each input file as the date and time of the last update of each corresponding output file.\n\n- **replace**\n Causes the output file to replace an existing file with the same file identifier.\n\n4. Erase product parameter file from A disk\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>erase P696234K $PPF a</td>\n<td>Do not use your own PPF name in place of P696234K for this ERASE command.</td>\n</tr>\n</tbody>\n</table>\n\n5. Update build status table\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfbld ppf P696234K {HLASM</td>\n<td>HLASMSFS} {status}</td>\n</tr>\n</tbody>\n</table>\n\nUse HLASM if HLASM Toolkit Feature is installed on minidisk.\nUse HLASMSFS if HLASM Toolkit Feature is installed in SFS.\n\n1 When you receive the VMFBLD2185R prompt, enter a 1 to continue.\n\n**Options:**\n\n- **status** Identifies build requirements.\n\n6. Review the build message log\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfview build</td>\n<td>Command to review the build status messages and see which objects need to be built.</td>\n</tr>\n</tbody>\n</table>\n\n**Step 7: Rebuild serviced parts (objects)**\n\n1. Rebuild serviced parts\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfbld ppf P696234K {HLASM</td>\n<td>HLASMSFS} {serviced}</td>\n</tr>\n</tbody>\n</table>\nStep 7: Rebuild serviced parts (objects)\n\nCommand | Explanation\n--- | ---\ncommand | Command to rebuild serviced parts.\n\nUse \\#HLASM if HLASM Toolkit Feature is installed on minidisk.\nUse \\#HLASMSFS if HLASM Toolkit Feature is installed in SFS.\n\nOptions:\n\n- **serviced**\n Identifies build requirements and builds those objects flagged as **serviced** in the service-level build status table.\n\n2. Review build message log\n\nCommand | Explanation\n--- | ---\nvmfview build | Command to review the build message log ($VMFBLD $MSGLOG). Correct any problems before going on. For information about specific error messages, refer to **z/VM: Other Components Messages and Codes**.\n\nStep 8: Verify the service\n\nAfter you have applied all the files on the service tape, run the installation verification EXEC to ensure that the product functions properly.\n\nCommand | Explanation\n--- | ---\nT5696234 | Assembles then disassembles the sample program ASMTSAMP. It then invokes the Interactive Debug Facility to run the ASMTSAMP program.\n\nStep 9: Place the service into production\n\n1. Move service into production.\n a. Log on to MAINT if you plan to put HLASM Toolkit Feature general-use code on the ‘Y’ disk (MAINT’s 19E disk). Alternatively log on using the user ID of the owner of the disk which contains the production level of the HLASM Toolkit Feature code.\n b. Link to HLASM Toolkit Feature code and access MAINT’s Y disk.\n Choose which access is required depending on whether you have used a minidisk or SFS.\n For minidisk access:\n\nCommand | Explanation\n--- | ---\nlink P696234K 29e 29e rr access 29e e | Access HLASM Toolkit Feature code on a minidisk.\naccess 19e f | Access CMS’s Y disk.\nFor SFS access:\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>access vmsys:P696234K.HLASMTL.TESTPROD e</code></td>\n<td>Access HLASM Toolkit Feature code in an SFS directory.</td>\n</tr>\n<tr>\n<td><code>access 19e f</code></td>\n<td>Access CMS’s Y disk.</td>\n</tr>\n</tbody>\n</table>\n\nc. Move HLASM Toolkit Feature to the Y disk.\n All of the HLASM Toolkit Feature modules should be placed onto the Y disk using the VMFCOPY command.\n The ASMSMAC MACLIB should be copied, if you made this maclib containing structured macros available to users.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>vmfcopy * MODULE e = f2 (prodid P696234K%HLASM olddate replace)</code></td>\n<td>Copy Toolkit modules to the CMS Y disk.</td>\n</tr>\n<tr>\n<td><code>vmfcopy * MACLIB e = f2 (prodid P696234K%HLASM olddate replace)</code></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nOptions:\n\n- `olddate` \n Uses the date and time on each input file as the date and time of the last update of each corresponding output file.\n\n- `replace` \n Causes the output file to replace an existing file with the same file identifier.\n\n If you do not want to use the Y disk for general use code, log on as the owner of the disk where you will put the production level of the HLASM Toolkit Feature code.\n\n The VMFCOPY command updates the VMESS PARTCAT file on the 19E disk.\n\n If you want to move the Enhanced SuperC (SuperC) then you should also copy the SuperC parts to the Y disk. The parts you should copy are listed on page 41.\n\n If you want to move the cross reference facility (ASMXREF) then you should also copy the ASMXREF parts the Y disk. The parts you should copy are listed on page 41.\n\nd. Update the shared Y-stat on the saved Y disk file directory.\n 1) Define named saved system\n Creates a named saved system for CMS.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>vmfsetup zvm cms</code></td>\n<td>On z/VM, allows access to the SAMPNSS EXEC which resides on MAINT’s 193 disk.</td>\n</tr>\n<tr>\n<td><code>sampnss cms</code></td>\n<td>Create named saved system for CMS.</td>\n</tr>\n</tbody>\n</table>\nStep 9: Place the service into production\n\n2) Resave the CMS system\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ipl 190 clear parm savesys cms</td>\n<td>Resave CMS saved system to reflect the change to the Y-STAT (the saved Y disk file directory).</td>\n</tr>\n</tbody>\n</table>\n\nStep 10: Service on Program Understanding Tool\n\nService which has an impact on the Program Understanding Tool will be indicated in the cover letter supplied with the service. Once service has been applied then the Program Understanding Tool should be updated on the workstation. Refer to Appendix E, “Maintaining Program Understanding Tool on Windows,” on page 89 for information on how to do this.\n\nRemoving HLASM Toolkit Feature\n\nYou use the VMFINS DELETE command to remove HLASM Toolkit Feature from your system. For information about removing product code and resources from your z/VM system, see the section about the VMFINS DELETE command in z/VM: VMSES/E Introduction and Reference.\n\nReporting a problem with HLASM Toolkit Feature\n\nTo assist with reporting any difficulties, refer to the diagnostic process as shown in the HLASM Installation and Customization Guide. Report any difficulties with this product to your IBM Support Center. If an APAR is required, the Support Center will provide the address to which any needed documentation can be sent.\n\nTable 26 identifies the component ID (COMP ID) for HLASM Toolkit Feature for z/VM.\n\nTable 26. Component IDs\n\n<table>\n<thead>\n<tr>\n<th>COMP ID</th>\n<th>Component Name</th>\n<th>REL</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>569623401</td>\n<td>VM HLA TOOLKIT FEATURE</td>\n<td>36A</td>\n</tr>\n</tbody>\n</table>\n\nObtaining service information\n\nPreventive Service Planning (PSP) information is continually updated as fixes are made available for problems. Check with your IBM Support Center or use IBMLink® (ServiceLink) to see whether there is additional PSP information you need. To obtain this information, specify the following UPGRADE and SUBSET values: HLASM160 and HLASMVM36A.\nPart 3. On z/VSE: planning for, installing, and maintaining High Level Assembler Toolkit Feature\n\nChapter 7. Planning for installing HLASM Toolkit\nFeature on z/VSE ........................................... 55\nWorksheet: Planning for installing HLASM Toolkit\nFeature on z/VSE ........................................... 55\nWhat you receive with HLASM Toolkit Feature .......... 56\n Distribution media ........................................ 56\n Basic material ........................................... 56\n Optional material ....................................... 56\n Cumulative service tape ................................ 56\n Program publications and softcopy ..................... 56\n Program source materials ............................... 57\nWhat you need to install HLASM Toolkit Feature ........ 57\n Required and optional software ....................... 57\nPlanning where to install HLASM Toolkit Feature ....... 58\n Program support ......................................... 58\n Program services ....................................... 58\n Preventive Service Planning ............................ 58\n Statement of support procedures ..................... 59\nProgram and service level information .................... 59\n Program level information ............................. 59\n Service level information ............................. 59\n Cumulative service tape ............................... 59\nPublications useful during installation ................... 59\n\nChapter 8. Installing HLASM Toolkit Feature on z/VSE\n ............................................................. 61\nOverview of installation .................................. 61\n Checklist for installing HLASM Toolkit Feature ..... 61\nStep 1: Allocate space for the library (omit if using the default) ............................................. 61\nStep 2: Install HLASM Toolkit Feature .................. 63\n Method 1: Install HLASM Toolkit Feature using the interactive interface with V2 Format tape .... 63\n Condition code and messages ....................... 64\n Method 2: Install HLASM Toolkit Feature using the interactive interface with V1 Format tape .... 65\n Condition code and messages ....................... 65\n Method 3: Install HLASM Toolkit Feature using a batch job ............................................. 65\nStep 3: Load HLASM Toolkit Feature into shared virtual area (SVA) ........................................ 67\nStep 4: Verify the installation of HLASM Toolkit Feature ...................................................... 68\n Run the installation verification job .................. 69\nStep 5: Configure VTAM .................................... 69\nStep 6: Download Program Understanding Tool ....... 70\nStep 7: Create cross-reference facility files ........... 70\n\nChapter 9. Maintaining HLASM Toolkit Feature\non z/VSE .................................................... 71\nRe-installing HLASM Toolkit Feature ..................... 71\nApplying service updates .................................. 71\n What you receive ....................................... 71\n Checklist for applying service ....................... 71\nStep 1: Check prerequisite APARs or PTFs ................ 72\nStep 2: Backup existing system ........................... 72\nStep 3: Apply service ...................................... 72\n Method 1: Apply service using the interactive interface ..................................................... 72\n Method 2: Apply service using a batch job ........... 73\nStep 4: Run the installation verification program (IVP) ...................................................... 74\nStep 5: Service on Program Understanding Tool ....... 74\nRemoving HLASM Toolkit Feature ........................ 74\nTo report a problem with HLASM Toolkit Feature ....... 74\nObtaining service information ............................ 75\nChapter 7. Planning for installing HLASM Toolkit Feature on z/VSE\n\nThis section contains the following planning information to help you properly install HLASM Toolkit Feature on z/VSE:\n- Worksheet\n- What you receive with HLASM Toolkit Feature\n- Choosing required and optional software\n- Verifying that you have enough DASD storage\n- Deciding where to install\n- Program Support\n- Program and Service Level Information\n\nWorksheet: Planning for installing HLASM Toolkit Feature on z/VSE\n\nBefore you begin the installation you should:\n\n1. Determine which of the following you are installing HLASM Toolkit Feature from:\n - A V2 Format tape (with one or more products besides HLASM Toolkit Feature)\n - A tape with just HLASM Toolkit Feature on it\n See “What you receive with HLASM Toolkit Feature” on page 56.\n\n2. Determine the product parts to be installed:\n - COMPID 569623401\n - Feature number 5882\n - Tape label unlabeled\n See “Basic material” on page 56.\n\n3. Verify that required software (and optional software, if appropriate) is at the level needed. See “What you need to install HLASM Toolkit Feature” on page 57.\n\n4. Verify that adequate storage is available. See “DASD and other storage required” on page 57.\n\n5. Determine how you are going to install HLASM Toolkit Feature:\n - Using Interactive Interface.\n - Using a batch installation job.\n See “Planning where to install HLASM Toolkit Feature” on page 58.\n\n6. Determine which of the following you want to install in:\n - Default library and sublibrary\n - A different library and sublibrary\n If using a different library and sublibrary, verify that space is sufficient. See “Planning where to install HLASM Toolkit Feature” on page 58.\n\n7. Check on latest service updates needed. See “Program support” on page 58.\n\nWhat you receive with HLASM Toolkit Feature\n\nYou receive the following when you order HLASM Toolkit Feature:\n\n<table>\n<thead>\n<tr>\n<th>COMPIIDs</th>\n<th>Feature Number</th>\n<th>System Name</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>569623401</td>\n<td>5882</td>\n<td>z/VSE</td>\n</tr>\n</tbody>\n</table>\n\nDistribution media\n\nHLASM Toolkit Feature is distributed on the following:\n\n- 3480 tape cartridge\n\nThe cartridge contains all the programs and data needed for installation.\n\nBasic material\n\nTable 27 describes the program cartridge. Table 28 describes the file content of the program cartridge. z/VSE uses the Maintain System History Program (MSHP) to install this product.\n\nTable 27. Basic material: program cartridge\n\n<table>\n<thead>\n<tr>\n<th>Medium</th>\n<th>Feature Number</th>\n<th>Physical Volume</th>\n<th>External Label Identification</th>\n<th>VOLSER</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>3480 cart.</td>\n<td>5882</td>\n<td>1</td>\n<td>HLASM TLKT VSE R6</td>\n<td>unlabeled</td>\n</tr>\n</tbody>\n</table>\n\nTable 28. Program cartridge: file content\n\n<table>\n<thead>\n<tr>\n<th>File</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>Header file containing HLASM Toolkit Feature copyright statement</td>\n</tr>\n<tr>\n<td>2</td>\n<td>Backup file ID “HLASM.TLKT.1.6.0” followed by a MSHP System History File</td>\n</tr>\n<tr>\n<td>3</td>\n<td>HLASM Toolkit Feature library file containing the production sublibrary</td>\n</tr>\n<tr>\n<td>4</td>\n<td>Tape mark</td>\n</tr>\n<tr>\n<td>5</td>\n<td>End of backup record</td>\n</tr>\n<tr>\n<td>6</td>\n<td>Tape mark</td>\n</tr>\n</tbody>\n</table>\n\nOptional material\n\nThere are no optional machine-readable materials for HLASM Toolkit Feature.\n\nCumulative service tape\n\nYou might receive an additional tape containing cumulative service with your order. The PTFs on this tape have not yet been incorporated into this release.\n\nProgram publications and softcopy\n\nThis section identifies the basic and optional publications for HLASM Toolkit Feature.\n\nOne printed copy of the following manuals is shipped free automatically with the product:\n\n- HLASM Licensed Program Specifications GC26-4944\n- HLASM Toolkit Feature Installation and Customization Guide GC26-8711\n- HLASM Toolkit Feature Interactive Debug Facility User’s Guide GC26-8709\nWhat you receive with HLASM Toolkit Feature\n\n- HLASM Toolkit Feature Debug Reference Summary GC26-8712\n- HLASM Toolkit Feature User’s Guide GC26-8710\n\nFor a list of books for related products, see \"Bibliography\" on page 91.\n\nProgram source materials\nThere are no source materials available for HLASM Toolkit Feature.\n\nWhat you need to install HLASM Toolkit Feature\nThe following sections identify the system requirements for installing HLASM Toolkit Feature.\n\nRequired and optional software\nThis section describes the environment required to install and use HLASM Toolkit Feature.\n\nHLASM Toolkit Feature runs on z/VSE with the required licensed programs listed in [Table 29] You should install all licensed programs with the minimum release listed or with any subsequent release.\n\nTable 29. Required programs\n\n<table>\n<thead>\n<tr>\n<th>Required Licensed Program</th>\n<th>Minimum Version Supported</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>z/VSE</td>\n<td>Version 3 Release 1</td>\n</tr>\n<tr>\n<td>HIGH LEVEL ASSEMBLER for z/OS &</td>\n<td>Version 1 Release 6</td>\n</tr>\n<tr>\n<td>z/VM & z/VSE</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nNote: The IDF component of HLASM Toolkit Feature requires REXX/VSE to be initialized and activated. For more information about initializing REXX/VSE, refer to the REXX/VSE Reference book for your z/VSE system.\n\nDASD and other storage required\nThe DASD storage requirements of HLASM Toolkit Feature must be added to the storage required by other programs having data in the same library. An estimate of required space is the data set’s current allocation plus the storage required by HLASM Toolkit Feature.\n\nThe library must have free the number of library blocks shown in [Table 30]. A library block equals 1 kilobyte. For example, 10 library blocks equal 10,240 bytes. These values allow for subsequent service and functional enhancements. A LIBR RESTORE function with the SCAN option will provide an exact amount.\n\nTable 30 also allows for space for service application.\n\nTable 30. Library requirements\n\n<table>\n<thead>\n<tr>\n<th>Product Tapefile-id</th>\n<th>LIBR BLKS</th>\n<th>3380 CYL</th>\n<th>3390 CYL</th>\n<th>FBA BLKS</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>HLASM.TLKT.1.6.0</td>\n<td>18000</td>\n<td>39</td>\n<td>37</td>\n<td>36000</td>\n</tr>\n</tbody>\n</table>\n\nIf you plan to install this product in a separate MSHP history file, refer to [Table 31] on page 58 for MSHP DASD space requirements.\nPlanning where to install HLASM Toolkit Feature\n\nThe HLASM Toolkit Feature default library is PRD2; the default sublibrary is PROD. All HLASM Toolkit Feature installation jobs assume you are using the sublibrary PRD2.PROD. To install HLASM Toolkit Feature in a different library and sublibrary, you must change some names in the installation jobs.\n\nYou might have selected PRD2 as a library because other products that work with HLASM Toolkit Feature use PRD2 as a default library. If you plan to install HLASM Toolkit Feature to an existing PRD2.PROD sublibrary, make sure there is enough free space to accommodate the additional library blocks.\n\nTo check the space, list the directory information of the PRD2 library, using the LISTDIR command of the LIBR program. Make sure there are sufficient library blocks in the free space.\n\nYou can use the Interactive Interface to install HLASM Toolkit Feature or the documented sample batch job.\n\nAll the sample batch jobs shown in this manual are supplied as .Z books in the installed library. They are also supplied as .I books for addition to ICCF library 62. If the product is installed using the Interactive Interface then these ICCF members are added to ICCF library 62 by the install process. These have the same name except, the fourth character is an I, for example there is ASMTVTOC.Z and its ICCF equivalent is ASMIVTOC.I.\n\nProgram support\n\nThis section describes the IBM support available for HLASM Toolkit Feature.\n\nProgram services\n\nContact your IBM representative for specific information about available program services.\n\nPreventive Service Planning\n\nBefore installing HLASM Toolkit Feature, you should review the current Preventive Service Planning (PSP) information.\n\nPSP Buckets are identified by UPGRADEs, which specify product levels, and SUBSETs, which specify the CLCs for a product level. The UPGRADE and SUBSET values for HLASM Toolkit Feature for z/VSE are:\n\n<table>\n<thead>\n<tr>\n<th>UPGRADE</th>\n<th>SUBSET</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>HLASM160</td>\n<td>HLASMVSE6IM</td>\n<td>HLASM Toolkit VSE</td>\n</tr>\n</tbody>\n</table>\n\nWhat you need to install HLASM Toolkit Feature\n\n<table>\n<thead>\n<tr>\n<th>File</th>\n<th>3380 CYL</th>\n<th>3390 CYL</th>\n<th>FBA BLKS</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>IJSYSHF</td>\n<td>1</td>\n<td>1</td>\n<td>900</td>\n</tr>\n</tbody>\n</table>\nStatement of support procedures\n\nReport any difficulties you have using this program to your IBM Support Center. If an APAR is required, the Support Center will provide the address to which any needed documentation can be sent.\n\nTable 11 on page 10 identifies the component ID (COMPID) for HLASM Toolkit Feature for z/VSE.\n\nTable 33. Component IDs\n\n<table>\n<thead>\n<tr>\n<th>CLC</th>\n<th>COMPID</th>\n<th>Component Name</th>\n<th>RETAIN Release</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>6IM</td>\n<td>569623401</td>\n<td>VSE HLA TOOLKIT FEATURE</td>\n<td>6IM</td>\n</tr>\n</tbody>\n</table>\n\nProgram and service level information\n\nThis section identifies the program and any relevant service levels of HLASM Toolkit Feature. The program level refers to the APAR fixes incorporated into the program. The service level refers to the PTFs integrated. Information about the cumulative service tape is also provided.\n\nProgram level information\n\nA list of APAR fixes against previous releases of HLASM Toolkit Feature that have been incorporated into this release is shown in Appendix A, “HLASM Toolkit Feature Service,” on page 79.\n\nService level information\n\nNo PTFs against this release of HLASM Toolkit Feature have been incorporated into the product tape.\n\nCumulative service tape\n\nA cumulative service tape, containing PTFs not incorporated into this release, might be included with this program. Installation instructions for cumulative service tapes can be found in the SMP/E publications.\n\nIf you received this product as part of a CBPDO or a ProductPac, PTFs not incorporated into this release are provided on the tape, and a separate cumulative service tape will not be provided.\n\nPublications useful during installation\n\nThe publications listed in Table 34 may be useful during the installation of HLASM Toolkit Feature for z/VSE.\n\nTable 34. z/VSE publications\n\n<table>\n<thead>\n<tr>\n<th>Publication Title</th>\n<th>Form Number</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>z/VSE: Guide to System Functions</td>\n<td>SC33-8233</td>\n</tr>\n<tr>\n<td>z/VSE: Administration</td>\n<td>SC33-8224</td>\n</tr>\n<tr>\n<td>z/VSE: Installation</td>\n<td>SC33-8222</td>\n</tr>\n<tr>\n<td>z/VSE: Planning</td>\n<td>SC33-8221</td>\n</tr>\n<tr>\n<td>z/VSE: System Control Statements</td>\n<td>SC33-8225</td>\n</tr>\n</tbody>\n</table>\n### Publications useful during installation\n\n<table>\n<thead>\n<tr>\n<th>Publication Title</th>\n<th>Form Number</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>z/VSE: Messages and Codes - Vols. 1 - 3</td>\n<td>SC33-8226, SC33-8227, SC33-8228</td>\n</tr>\n</tbody>\n</table>\n\nTable 34. z/VSE publications (continued)\nChapter 8. Installing HLASM Toolkit Feature on z/VSE\n\nThis chapter describes the installation method and the step-by-step procedures you use to install and activate the functions of HLASM Toolkit Feature.\n\nOverview of installation\n\nYou install this release of HLASM Toolkit Feature by using the Maintain System History Program (MSHP).\n\nChecklist for installing HLASM Toolkit Feature\n\nTable 35 lists the steps and associated jobs for installing HLASM Toolkit Feature. The remaining sections in this chapter describe each step. You can use Table 35 as a checklist.\n\nTable 35. Summary of steps for installing HLASM Toolkit Feature\n\n<table>\n<thead>\n<tr>\n<th>Step</th>\n<th>Description</th>\n<th>Installation Job</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>__ _1</td>\n<td>Allocate space for the library.</td>\n<td>ASMTDEF</td>\n<td>61</td>\n</tr>\n<tr>\n<td></td>\n<td>(Omit if using the default.)</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>_2</td>\n<td>Install HLASM Toolkit Feature.</td>\n<td></td>\n<td>63</td>\n</tr>\n<tr>\n<td></td>\n<td>Method 1. Install HLASM Toolkit Feature using the</td>\n<td></td>\n<td>63</td>\n</tr>\n<tr>\n<td></td>\n<td>Interactive Interface with HLASM Toolkit Feature on an</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Optional Products (V2 Format) tape.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Method 2. Install HLASM Toolkit Feature using the</td>\n<td></td>\n<td>65</td>\n</tr>\n<tr>\n<td></td>\n<td>Interactive Interface with HLASM Toolkit Feature as the</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>only product on the (V1 Format) tape.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Method 3. Install HLASM Toolkit Feature using a batch</td>\n<td>ASMTINST</td>\n<td>65</td>\n</tr>\n<tr>\n<td></td>\n<td>job.</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>_3</td>\n<td>Load HLASM Toolkit Feature into the SVA</td>\n<td>ASMTSVA2</td>\n<td>67</td>\n</tr>\n<tr>\n<td>_4</td>\n<td>Verify the installation of HLASM Toolkit Feature.</td>\n<td>ASMTIVPS</td>\n<td>68</td>\n</tr>\n<tr>\n<td>_5</td>\n<td>Configure VTAM</td>\n<td>ASMTAPPL</td>\n<td>69</td>\n</tr>\n<tr>\n<td>_6</td>\n<td>Download Program Understanding Tool to workstation.</td>\n<td></td>\n<td>70</td>\n</tr>\n<tr>\n<td>_7</td>\n<td>Create Cross-Reference Facility Files</td>\n<td>ASMXJC2S</td>\n<td>70</td>\n</tr>\n</tbody>\n</table>\n\nStep 1: Allocate space for the library (omit if using the default)\n\nBy default, HLASM Toolkit Feature is installed into the PRD2.PROD sublibrary for z/VSE. If you decide to install HLASM Toolkit Feature into a sublibrary other than PRD2.PROD then proceed with this step.\n\nDecide where to allocate space for the HLASM Toolkit Feature sublibrary. Identify, on the disk volume (or volumes) to be used for the library, suitable areas of free space. To do this, list the volume table of contents (VTOC) of the disk or disks to be used.\nStep 1: Allocate space for the library (omit if using the default)\n\nChoose one of the following jobs to list the VTOC:\n\n1. Use the LVTOC utility program. The sample job shown in Figure 3 shows the JCL needed to list the VTOC for the volume with serial number SYSWK1.\n\n```plaintext\n// JOB ASMTVTOC LIST VOLUME TABLE OF CONTENTS\n// ASSGN SYS004,DISK,TEMP,VOL=SYSWK1,SHR\n// ASSGN SYS005,SYSLST\n// EXEC LVTOC\n/*\n/&\n```\n\n**Figure 3. Job to list the contents of a DASD volume**\n\n2. Use the DITTO utility program\n\nAs an alternative to using the system utility LVTOC, DITTO’s Display VTOC (DVT) may be used. Figure 4 shows a sample job.\n\n```plaintext\n// JOB ASMTDITT LIST VOLUME TABLE OF CONTENTS\n// UPSI 1\n// ASSGN SYS001, cuu\n// EXEC DITTO, SIZE=512K\n$DITTO DVT INPUT=SYS001, SORTBY=EXTENT\n$DITTO EOJ\n/*\n/&\n```\n\n**Figure 4. Job to list the contents of a DASD volume**\n\nUse the disk space selected for HLASM Toolkit Feature in the LIBR installation job to allocate the z/VSE Librarian library in the sample job shown in Figure 5.\n\n```plaintext\n// JOB ASMTDEF\n* CREATE A LIBRARY FOR THE High Level Assembler Toolkit Feature\n// OPTION LOG\n* Label for the HLASM Toolkit Feature\n* Library\n// DLBL HLASM'T, 'HLASM.TOOLKIT.LIBRARY', 99/365, SD\n// EXTENT SYS002, SYSWK1, , rtrk, ntrk\n// ASSGN SYS002, DISK, VOL=SYSWK1, SHR\n* ------------------------------------------\n* Define the High Level Assembler Toolkit Feature Library\n* ------------------------------------------\n// EXEC LIBR\nDELETE LIB=HLASM\nDEFINE LIB=HLASM\n/*\n/&\n```\n\n**Figure 5. Job to allocate the HLASM Toolkit Feature library space**\n\nIn area 1 change the `filename` (HLASMT in the example) and `file-id` (HLASM.TOOLKIT.LIBRARY in the example) of HLASM Toolkit Feature to suit the requirements of your site. Points to consider are:\n\n- The variable `ntrk` indicates the number of tracks or blocks required. See Table 30 on page 57 for the number of tracks or blocks for your DASD type.\nStep 1: Allocate space for the library (omit if using the default)\n\n- The variable *rtrk* represents the start position of the extent.\n\nThe Librarian job step in area 2 includes a DELETE statement before the DEFINE statement so the job can be rerun. The following informational messages are issued when the job runs for the first time. The job continues to allocate the library.\n\nThe messages are:\n\nL101I LIBRARY HLASM DOES NOT EXIST\nL027I ABNORMAL END DURING DELETE COMMAND\nPROCESSING\nL113I RETURN CODE OF DELETE IS 8\n\nStep 2: Install HLASM Toolkit Feature\n\nYou can install HLASM Toolkit Feature using either the Interactive Interface of z/VSE or a batch installation job.\n\nMethod 1: Install HLASM Toolkit Feature using the interactive interface with V2 Format tape\n\nCarry out the following tasks:\n\n1. Mount the HLASM Toolkit Feature tape on an available tape drive.\n2. Library Labels\n If the product is not being installed in the default library, then the library to contain HLASM Toolkit Feature must have its DLBL and EXTENT in the label information area.\n3. Log on to the Interactive Interface\n To install HLASM Toolkit Feature using the Interactive Interface, log on to the z/VSE Interactive Interface as the system administrator. For more information about the functions of the Interactive Interface, refer to z/VSE: Administration\n In the following menus, enter the highlighted items that appear after the => symbol.\n4. Mount the HLASM Toolkit Feature tape on an available tape drive.\n5. In the z/VSE FUNCTION SELECTION menu, select:\n => 1 (Installation)\n6. In the INSTALLATION menu:\n You have received HLASM Toolkit Feature as a V2 Format tape, which contains one or more optional products, therefore select:\n => 1 (Install Programs - V2 Format)\n7. In the INSTALL PROGRAMS - V2 FORMAT menu, select:\n => 1 (Prepare for Installation)\n8. In the PREPARE FOR INSTALLATION menu, select:\n => cuu (the address of the tape drive where you mounted the distribution tape.)\n (If you are using a virtual tape, enter 1 for Virtual Tape, otherwise enter 2.)\n9. In the JOB DISPOSITION menu:\n Make any changes required and press Enter to submit the job.\n10. Respond to console messages\n When the job starts it asks if the tape is ready. After the tape is scanned it asks if further tapes are to be read. Refer to Figure 6 on page 64 for examples of the console messages.\nMethod 1: Install HLASM Toolkit Feature using the interactive interface with V2 Format tape\n\n01 BG 000 IES10091I PLEASE MOUNT TAPE LABELLED \"VSE OPTIONAL TAPE NUMBER\n02+BG 000 IES10092A MOUNT ON TAPE DRIVE 580 . WHEN READY, REPLY \"END/ENTER\"\n03+BG-000\n04 0\n05+BG 000 IES10090A ARE THERE ANY MORE OPTIONAL PROGRAM TAPES? YES/NO\n06+BG-000\n10 0 no\n11 BG 000 EOJ INSPE MAX.RETURN CODE=0000\n\nFigure 6. Console messages\n\nThe output listing from this job gives a list of the optional programs on the distribution tape with program identifiers and recommended library sizes. The tapefile identifier for HLASM Toolkit Feature is HLASM.TLKT.1.6.0.\n\nThe program identifiers of the optional programs on the distribution tape are also automatically entered on the INSTALL ADDITIONAL PROGRAM(S) FROM TAPE menu.\n\n11. Return to the z/VSE FUNCTION SELECTION menu, and enter:\n\n ====> 1 (Installation)\n\n12. In the INSTALLATION menu, select:\n\n ====> 1 (Install Programs - V2 Format)\n\n13. In the INSTALL PROGRAMS - V2 FORMAT menu, select:\n\n ====> 2 (Install Program(s) from Tape)\n\n14. In the INSTALL ADDITIONAL PROGRAM(S) FROM TAPE menu:\n\n Enter 1 (install) in the OPT field against the tapefile identifier\n\n HLASM.TLKT.1.6.0 (HLASM Toolkit Feature)\n\n and 2 (skip installation) against any other optional products you do not intend to install at this time.\n\n If you did not use the default library PRD2.PROD, enter the name of your library and sublibrary on this screen. The DLBL and EXTENT information for this library should already be in the label information area.\n\n Press PF5 to generate the installation job.\n\n15. Retain products list\n\n Decide if you want to keep the product list previously generated from LIBR utility scan of the product tape.\n\n16. In the INSTALL ADDITIONAL PROGRAM(S) FROM TAPE menu, enter:\n\n ====> cuu\n\n (the address of the tape drive where you mounted the HLASM Toolkit Feature tape.)\n\n (If you are using a virtual tape, enter 1 for Virtual Tape, otherwise enter 2.)\n\n17. In the JOB DISPOSITION menu:\n\n Make any changes required and press ENTER to submit the job to install HLASM Toolkit Feature.\n\n18. Respond to console messages\n\n Confirm prompt when asking for tape to install product.\n\nCondition code and messages\n\nIf you do not receive a condition code of 0:\n\n1. Check the list output for error conditions.\n\n2. See z/VSE: Messages and Codes for corrective action.\n3. Correct the error.\n4. Rerun the job.\n5. Recheck the condition code.\n\nMethod 2: Install HLASM Toolkit Feature using the interactive interface with V1 Format tape\n\nCarry out the following tasks:\n1. Log on to the Interactive Interface\n To install HLASM Toolkit Feature using the Interactive Interface, log on to the z/VSE Interactive Interface as the system administrator. For more information about the functions of the Interactive Interface, refer to z/VSE: Administration.\n In the following menus enter the highlighted items that appear after the symbol.\n2. Mount the HLASM Toolkit Feature tape on an available tape drive.\n3. In the z/VSE FUNCTION SELECTION menu, select:\n ====> 1 (Installation)\n4. In the INSTALLATION menu:\n You received HLASM Toolkit Feature as a V1 Format tape, which contains HLASM Toolkit Feature, therefore select:\n ====> 2 (Install Programs - V1 Format)\n5. In the INSTALL PROGRAMS - V1 FORMAT menu select:\n ====> HLASM.TLKT.1.6.0 (Tapefile-id)\n If you did not use the default library PRD2.PROD, enter the name of your library and sublibrary on this screen. The DLBL and EXTENT information for this library should already be in the label information area.\n Press PF5 to generate the installation job.\n6. In the INSTALL ADDITIONAL PROGRAM(S) FROM TAPE menu, enter:\n ====> cuu (the address of the tape drive where you mounted the HLASM Toolkit Feature tape.)\n (If you are using a virtual tape, enter 1 for Virtual Tape, otherwise enter 2.)\n7. In the JOB DISPOSITION menu:\n Make any changes required and press Enter to submit the job to install HLASM Toolkit Feature.\n8. Respond to console messages\n Confirm prompt when asking for tape to install product.\n\nCondition code and messages\nIf you do not receive a condition code of 0:\n1. Check the list output for error conditions.\n2. See z/VSE: Messages and Codes for corrective action.\n3. Correct the error.\n4. Rerun the job.\n5. Recheck the condition code.\n\nMethod 3: Install HLASM Toolkit Feature using a batch job\nThe batch installation job stream for installing HLASM Toolkit Feature uses the MSHP system history file that already exists as part of the z/VSE system. This system history file might already be defined in the system standard labels; if not,\nMethod 3: Install HLASM Toolkit Feature using a batch job\n\nmake sure that DLBL and EXTENT statements, with the necessary information for the system history file, are included in the job stream.\n\nDepending on how you request the HLASM Toolkit Feature product you might receive different installation tapes. One could contain only the HLASM Toolkit Feature product (V1 Format tape), the other might be a V2 Format tape containing one or more optional program products. The job shown in Figure 7 handles both types of tape (V2 Format and V1 Format).\n\nCreate and tailor the following job stream, mount the distribution tape, and run the installation job.\n\nFigure 7 provides the JCL required to install HLASM Toolkit Feature. Tailor this JCL to suit the requirements at your site.\n\nAs many as five modifications might be required to tailor the JCL. The keys in Figure 7 are explained individually and refer to the sections that accompany the JCL description.\n\n```\n// JOB ASMTINST\n* INSTALL THE High Level Assembler Toolkit Feature LIBRARY\n// OPTION LOG\n* Label for High Level Assembler Toolkit Feature Library 1\n* Assign install tape as SYS006 2\n// ASSGN SYS006, cuu\n// MTC REW, SYS006\n* ----------------------------------------\n* This step installs High Level Assembler Toolkit Feature\n* from the distribution tape\n* using the VSE system history file 3\n* ----------------------------------------\n// EXEC MSHP, SIZE=900K, PARM='PIDSTACKED'\nINSTALL PROD FROMTAPE ID='HLASM.TLKT.1.6.0' -\n PROD INTO=PRD2.PROD\n/\n* ----------------------------------------\n* List the High Level Assembler Toolkit Feature Library 4\n* ----------------------------------------\n// EXEC LIBR\nLISTDIR SUBLIB=PRD2.PROD -\n OUTPUT=NORMAL -\n UNIT=SYSLST\n/\n* ----------------------------------------\n* Retrace the High Level Assembler Toolkit Feature product 5\n* ----------------------------------------\n// EXEC MSHP, SIZE=900K\nRETRACE COMPONENT IDENTIFIER=5696-234-01\n/\n// MTC RUN, SYS006\n/\n&\n```\n\nFigure 7. Job to install HLASM Toolkit Feature\n\n1. Specify the Label Information\n\n In area 4, if you are installing HLASM Toolkit Feature into a sublibrary other than the default then insert DLBL, EXTENT and ASSGN information as specified in Figure 5 on page 62. The library name must match the name used in the allocation job in Figure 5.\nMethod 3: Install HLASM Toolkit Feature using a batch job\n\nThere is no DLBL statement for the system history file. Typically it would have a permanent system standard label for this, with IJSYSHF as the file name. (IJSYSHF is the default file name that MSHP looks for in a label statement.)\n\n2. Assign the Distribution Tape\n Assign the distribution tape in area 2 to logical unit SYS006. Replace cuu with the address of the tape drive on which the distribution tape is mounted. Alternatively you may use the generic tape assignment:\n // ASSGN SYS006,TAPE\n\n3. Install HLASM Toolkit Feature\n Area 3 of the job calls MSHP to install HLASM Toolkit Feature into the sublibrary identified on the INTO operand of the INSTALL statement. If you are installing HLASM Toolkit Feature into a sublibrary other than the default, then change the name of the sublibrary on the INTO operand of the INSTALL statement to reflect this sublibrary. For more information about the install options, see “Maintain System History Program (MSHP)” in /VSE: System Control Statements.\n\n4. List the Directory Entries\n The step in area 4 of the job lists the directory entries of the sublibrary where HLASM Toolkit Feature was installed. Remove this step if a directory list is not required. If you have installed HLASM Toolkit Feature into a sublibrary other than the default, then the name of the sublibrary must be changed to reflect the value you specified in area 3.\n Entries for HLASM Toolkit Feature have a three character prefix of ASM to distinguish them from other products; there are three exceptions to this rule:\n • HD2346M.Z\n • $SVAASMT.PHASE\n • $SVAASMT.OBJ\n\n5. Retrace the HLASM Toolkit Feature product in the system history file.\n The final step in area 5 of the job prints the component records from the system history file for HLASM Toolkit Feature. Remove this step if a retrace listing is not required.\n If this job has to be run again, remember first to restore the system history file, which should have been backed up before running this install job, and second to run the library allocation step again, if applicable.\n\nStep 3: Load HLASM Toolkit Feature into shared virtual area (SVA)\n\nThe IDF component of HLASM Toolkit Feature makes extensive use of vendor exits. Therefore some HLASM Toolkit Feature phases must be loaded into the SVA. These phases are:\n ASMPCKEX\n ASMPGLEX\n AMSVCEX\n ASMDFRX\n\nTo load these phases into the SVA, do the following:\n\n1. Modify the SVA statement of the VSE IPL ASI (Automated System Initialization) procedure to allow space for the phases:\n • Increase the SDL parameter by the number of new phases being added to the SVA.\n • Increase the PSIZE parameter by the amount of storage required to contain the new phases being added to the 24-bit and 31-bit SVA.\nStep 3: Load HLASM Toolkit Feature into shared virtual area (SVA)\n\n2. Modify the z/VSE background (BG) ASI procedure to automatically load the required phases into the SVA:\n - Modify the ALLOC statements for the partitions to ensure that the remaining storage is large enough to contain the phases.\n - Modify the LIBDEF PHASE SEARCH job control statement preceding the SET SDL statement to include the name of the sublibrary containing the HLASM Toolkit Feature phases.\n - The supplied SVA loadlist member, $SVAASMT, contains all the required HLASM Toolkit Feature phases that must reside in the SVA, as listed above.\n After the SET SDL statement, add the statement:\n ```\n LIST=$SVAASMT\n ```\n These phases have been built with the option SVAPFIX. When the phases are loaded into the SVA, they will go into PFIXed storage. This has a real storage requirement of at least 3K bytes.\n A sample batch job, ASMTSVA2, is supplied, which will load the phases in $SVAASMT into the SVA. This job must be run in the BG partition.\n For more information about PFIXed storage and loading phases into the SVA, see [z/VSE: System Control Statements](#) and [z/VSE: Guide to System Functions](#).\n\n3. Shut down and Re-IPL your z/VSE system.\n\nIn addition to loading phases into the SVA, to use vendor exits the application must be authorized. The users must be authorized (for example, via DTSECTAB) to access the phase $IJBVEND and the product exit routines. These routines are:\n\n- ASMPCKEX\n- ASMPGLEX\n- ASMSVCEX\n\nFor information about authorization using DTSECTAB, see [z/VSE: Administration](#).\n\nStep 4: Verify the installation of HLASM Toolkit Feature\n\nThe installation verification job will test if the product has been installed successfully. It will assemble a small assembler program, producing SYSADATA output. It will linkedit the program and process the SYSADATA output using the language extraction program.\nStep 4: Verify the installation of HLASM Toolkit Feature\n\n// JOB ASMTIVPS\n* 1\n* This will job will test if the HLASM Toolkit Feature\n* has been installed successfully.\n* 2\n// LIBDEF *,SEARCH=(PRD2.PROD,yourlib.sublib)\n// DLBL SYSADAT,'SYSADATA',0,VSAM,\n CAT=VSEPUC,RECSIZE=8192,\n DISP=(,KEEP),RECORDS=(500,500)\n// LIBDEF PHASE,CATALOG=yourlib.sublib\n// OPTION NOECK,CATAOL\n PHASE ASMBR14,*\n// EXEC ASMA90,SIZE=ASMA90,PARM='ADATA'\n ASMBR14 CSECT\n XR 15,15 Zero return code\n BR 14 Exit program\n END\n/* 3\n// EXEC ASMLKEDT\n/* 4\n// EXEC ASMLANGX,PARM='ASMBR14'\n*/\n/*\n\nFigure 8. Job to test successful installation\n\nThe x characters are in column 72.\n\n1. In area 1 and area 2, change yourlib.sublib to the library and sublibrary\n where the phase will be cataloged.\n2. In area 3, the program is linkedited.\n3. In area 4, language extraction is performed.\n\nRun the installation verification job\n\nFigure 8 shows the job ASMTIVPS.Z provided in the installed sublibrary. If you\ninstalled HLASM Toolkit Feature in a sublibrary other than the default, modify the\nIBM-supplied JCL that runs the verification job.\n\nRun the job listed in Figure 8 to verify the success of your installation.\n\nA return code of 0 for the job indicates that the verification job completed\nsuccessfully, and that the product is installed and functions correctly.\n\nStep 5: Configure VTAM\n\nThis step is required if you plan to use the Interactive Debug Facility of HLASM\nToolkit Feature to debug your batch programs interactively. A sample VTAM\ndefinition member, ASMTAPPL.B, is supplied in the install library to help you do\nthis. If you installed using the Interactive Interface, this member is also supplied as\nASMIAPPL in ICCF library 62.\n\n1. Either:\n • Copy the ASMTAPPL.B member to the source sublibrary containing your\n VTAM definition members.\n\n2. or\n • Copy the HLASM Toolkit Feature minor node definitions (APPL statements)\n from ASMTAPPL.B into one of your existing application major node\ndefinitions.\nStep 5: Configure VTAM\n\n- **Note:** The ASMTAPPL.B defines 20 application minor node names, ASMTL001 to ASMTL020. You can define up to 999 HLASM Toolkit Feature minor node names; the first five characters must be ASMTL and the last three characters must be consecutive 3-digit numbers, starting at 001.\n\n3. Add the source sublibrary member name (ASMTAPPL, or the name of the updated member) to your VTAM start options configuration file, ATCCONxx.\n4. Restart VTAM to activate the HLASM Toolkit Feature definitions.\n\n Until you restart VTAM, you can activate the HLASM Toolkit Feature definitions by entering the following command from your VTAM console:\n\n ```vary net,act,id=member-name,scope=all```\n\n where member-name is the source sublibrary member name (for example, ASMTAPPL).\n\nStep 6: Download Program Understanding Tool\n\nInstructions to download the Program Understanding Tool are contained in Appendix D, “Installing Program Understanding Tool on Windows,” on page 85.\n\nStep 7: Create cross-reference facility files\n\nThe Cross-Reference Facility requires two VSAM managed SAM files to be built at install time. The JCL for this task is in the ASMXJC2S.Z member.\n\nThis JCL will copy the contents from two librarian members (using ‘* $$ SLI’) into two VSAM managed SAM files. The user may, at a later date, update these librarian members and then rerun this JCL. When being rerun change DISP=(NEW,KEEP) to DISP=(OLD,KEEP) on the DLBL statements.\n\nBefore running this job, you will need to make the following changes:\n\n1. Change LDEST parameters on the '* $$ JOB’ statement, to suit the requirements of your site.\n2. Change the LIBDEF statement if you have installed HLASM Toolkit Feature into another library.\n3. Change the SLI statements if this library is not in the source LIBDEF search chain for the VSE/POWER™ partition. Do this by adding the ‘S=library:sublibrary’ parameter to each SLI statement.\n4. If necessary, change the IJSYSUC value on each DLBL statement to point to the required VSAM User Catalog.\nChapter 9. Maintaining HLASM Toolkit Feature on z/VSE\n\nThis chapter describes how to re-install or remove HLASM Toolkit Feature and how to apply service updates to HLASM Toolkit Feature. To use the maintenance procedures, you must have already installed HLASM Toolkit Feature and any required products.\n\nIn addition, this chapter describes how to remove HLASM Toolkit Feature.\n\nRe-installing HLASM Toolkit Feature\n\nYou do not need to perform all the planning and installation procedures to re-install HLASM Toolkit Feature. For example, you do not need to reconsider your storage needs if HLASM Toolkit Feature replaces existing HLASM Toolkit Feature data sets.\n\nYou do not need to remove HLASM Toolkit Feature from your system before re-installing HLASM Toolkit Feature, unless you intend to re-install the product in a different sublibrary from the previous installation. In this case you must remove HLASM Toolkit Feature from the system history file before you can re-install it.\n\nTo re-install HLASM Toolkit Feature, you follow the same steps as for installing HLASM Toolkit Feature. See Chapter 8, “Installing HLASM Toolkit Feature on z/VSE,” on page 61.\n\nApplying service updates\n\nYou might need to apply maintenance or service updates to HLASM Toolkit Feature periodically. This section details these procedures.\n\nWhat you receive\n\nIf you report a problem with HLASM Toolkit Feature to your IBM Support Center, you will receive a tape containing one or more APARs or PTFs to solve your problem.\n\nYou might also receive a list of APARs or PTFs, that should have been applied to your system before applying the current service. These APARs or PTFs might relate to HLASM Toolkit Feature or any other licensed product you have installed, including z/VSE.\n\nYou apply service to HLASM Toolkit Feature using either the z/VSE Interactive Interface or a batch job.\n\nThe following checklist provides a summary of steps you should use to apply service to HLASM Toolkit Feature.\n\nChecklist for applying service\n\nTable 36 on page 72 lists the steps for installing corrective service on HLASM Toolkit Feature.\n### Checklist for applying service\n\n#### Table 36. Summary of steps for installing service on HLASM Toolkit Feature\n\n<table>\n<thead>\n<tr>\n<th>Step</th>\n<th>Description</th>\n<th>MSHP Command or Jobname</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>__</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>_1</td>\n<td>Ensure prerequisite APARs or PTFs are applied.</td>\n<td>RETRACE</td>\n<td>72</td>\n</tr>\n<tr>\n<td>_2</td>\n<td>Backup existing system</td>\n<td></td>\n<td>72</td>\n</tr>\n<tr>\n<td>_3</td>\n<td>Apply service</td>\n<td>INSTALL</td>\n<td>72</td>\n</tr>\n<tr>\n<td>_4</td>\n<td>Run the installation verification program</td>\n<td>ASMTIVPS</td>\n<td>74</td>\n</tr>\n<tr>\n<td>_5</td>\n<td>Service on Program Understanding Tool</td>\n<td></td>\n<td>74</td>\n</tr>\n</tbody>\n</table>\n\n#### Step 1: Check prerequisite APARs or PTFs\n\nPrerequisite APARs or PTFs need to be applied to your system before you can apply the current maintenance. These APARs or PTFs might apply to HLASM Toolkit Feature or any licensed program you have installed at your site.\n\nYour IBM Support Center has given you a list of any relevant prerequisite APARs or PTFs. Probably most have been applied to your system. You can verify this by retracing the APARs and PTFs in your system history file. The job shown in Figure 9 shows how to retrace APARs and PTFs in the system history file. This job is supplied as ASMTRETR.Z\n\nUse this listing to check that you have already applied any pre-requisite APARs or PTFs. If you have not, arrange for your IBM Support Center to send them to you and apply them before applying other service.\n\n```\n// JOB ASMTRETR Retrace APARs and PTFs\n// EXEC MSHP,SIZE=700K\nRETRACE APARS\nRETRACE PTFS\n/*\n/*\n```\n\n**Figure 9. Job to retrace APARs and PTFs**\n\n#### Step 2: Backup existing system\n\nMake a backup copy of your current HLASM Toolkit Feature library and the system history file. For information about backing up libraries and the system history file, see [z/VSE: System Control Statements](#).\n\n#### Step 3: Apply service\n\nYou can apply service to HLASM Toolkit Feature from the provided service tape using either the Interactive Interface or a batch job.\n\n**Method 1: Apply service using the interactive interface**\n\nTo apply service to HLASM Toolkit Feature using the Interactive Interface, log on to the z/VSE Interactive Interface as the system administrator. For more information about the functions of the Interactive Interface, refer to [z/VSE: Administration](#).\n\nMount the service tape on an available tape drive.\nIn the following menus specify the highlighted items that appear after the `===>` symbol.\n\n1. **z/VSE FUNCTION SELECTION** menu:\n `===>` 1 (Installation)\n\n2. **INSTALLATION** menu:\n `===>` 4 (IBM Service)\n\n3. **IBM SERVICE** menu:\n `===>` 2 (PTF Handling)\n\n4. **PTF HANDLING** menu:\n - If you want to print the documentation about the supplied PTFs before applying the service, select:\n `===>` 1 (Print Service Document)\n **PRINT SERVICE DOCUMENTS** menu:\n `===>` 1 (Service medium (tape))\n `===>` `cuu` (the address of the tape drive where you mounted the service tape.)\n Enter 1 or 2 to select the type of document you want to print.\n - If you want to apply the service directly, select:\n `===>` 3 (Apply PTFs)\n **APPLY PTF** menu:\n `===>` 1 (Service medium (tape))\n `===>` `cuu` (the address of the tape drive where you mounted the service tape). Press Enter.\n `===>` **SERVICE UNIT NAME** (allocate a unique name for the service unit)\n Press Enter.\n\n5. **JOB DISPOSITION** menu:\n Make any changes required and press Enter to submit the job and apply the service.\n\n6. Respond to console messages:\n Confirm prompt when asking for service tape.\n\n**Method 2: Apply service using a batch job**\n\nThe batch job to apply service to HLASM Toolkit Feature uses the MSHP system history file where HLASM Toolkit Feature was installed.\n\nA sample job to apply service using MSHP is shown in Figure 10. This job is supplied as ASMTAPPZ. For more information on MSHP see z/VSE: System Control Statements.\n\n```\n// JOB ASMTAPP Apply Service\n// ASSGN SYS006,`cuu` 1\n// EXEC MSHP,SIZE=700K\nINSTALL SERVICE FROMTAPE 2\n/*\n&\n```\n\n*Figure 10. Job to install service*\n\nIn area 1, change `cuu` to the address of the tape drive where you have mounted the service tape.\nMethod 2: Apply service using a batch job\n\nArea 2 shows the MSHP statement to install service from a tape. The information in the system history file directs MSHP to apply the service to the sublibrary in which HLASM Toolkit Feature is installed. You do not need to supply this information.\n\nStep 4: Run the installation verification program (IVP)\n\nAfter you have applied all the files on the service tape, run the installation verification program ASMTIVPS to ensure that HLASM Toolkit Feature functions properly. Refer to “Step 3: Load HLASM Toolkit Feature into shared virtual area (SVA)” on page 67.\n\nStep 5: Service on Program Understanding Tool\n\nService which has an impact on the Program Understanding Tool will be indicated in the cover letter supplied with the service. Once service has been applied then the Program Understanding Tool should be updated on the workstation. Refer to Appendix E, “Maintaining Program Understanding Tool on Windows,” on page 89 for information on how to do this.\n\nRemoving HLASM Toolkit Feature\n\nYou do not have to remove HLASM Toolkit Feature from your system before installing a new version or release.\n\nIf you do have to remove HLASM Toolkit Feature for any reason, you must delete all the HLASM Toolkit Feature entries from your sublibrary and remove HLASM Toolkit Feature from the system history file.\n\nA sample job, ASMTDELV.Z, is supplied to help you do this. This job will:\n- delete all HLASM Toolkit Feature members from the sublibrary where it is installed\n- remove HLASM Toolkit Feature from System History File\n- update DTRIHIST.Z in the System Library to remove HLASM Toolkit Feature from the list of installed products\n\nConsult the instructions in the job for more information.\n\nTo report a problem with HLASM Toolkit Feature\n\nTo assist with reporting any difficulties refer to the diagnostic process as shown in HLASM Installation and Customization Guide.\n\nReport any difficulties you have using this product to your IBM Support Center. If an APAR is required, the Support Center will provide the address to which any needed documentation can be sent.\n\nTable 37 identifies the component ID (COMP ID) for HLASM Toolkit Feature for z/VSE.\n\n<table>\n<thead>\n<tr>\n<th>COMP ID</th>\n<th>Component Name</th>\n<th>REL</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>569623401</td>\n<td>VSE HLA TOOLKIT FEATURE</td>\n<td>6IM</td>\n</tr>\n</tbody>\n</table>\n\nTable 37. Component IDs\nObtaining service information\n\nPreventive Service Planning (PSP) information is continually updated as fixes are made available for problems. Check with your IBM Support Center or use either Information/Access or SoftwareXcel Extended to see whether there is additional PSP information that you need. To obtain this information, specify the following UPGRADE and SUBSET values: HLASM160 and HLASMVSE6IM.\nPart 4. Appendixes\nAppendix A. HLASM Toolkit Feature Service\n\nThe following service for HLASM Toolkit Feature Release 5 has been applied to Release 6:\n\nTable 38. Service history\n\n<table>\n<thead>\n<tr>\n<th>APAR</th>\n<th>z/OS PTF</th>\n<th>VM PTF</th>\n<th>VSE PTF</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>PQ90771</td>\n<td>UK04487</td>\n<td>UK04488</td>\n<td>UK04489</td>\n</tr>\n<tr>\n<td>PQ91484</td>\n<td>UQ93277</td>\n<td>UQ93278</td>\n<td>UQ93279</td>\n</tr>\n<tr>\n<td>PQ94993</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>PQ96247</td>\n<td>UK00566</td>\n<td>UK00568</td>\n<td>UK00570</td>\n</tr>\n<tr>\n<td>PQ98212</td>\n<td>UK02378</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>PK01063</td>\n<td>UK02493</td>\n<td>UK02495</td>\n<td>UK02497</td>\n</tr>\n<tr>\n<td>PK01283</td>\n<td>UK06158</td>\n<td>UK06164</td>\n<td>UK06191</td>\n</tr>\n<tr>\n<td>PK05664</td>\n<td>UK09195</td>\n<td>UK09197</td>\n<td>UK09199</td>\n</tr>\n<tr>\n<td>PK06190</td>\n<td>UK07105</td>\n<td>UK07107</td>\n<td>UK07109</td>\n</tr>\n<tr>\n<td>PK06707</td>\n<td>UK13411</td>\n<td>UK13413</td>\n<td>UK13415</td>\n</tr>\n<tr>\n<td>PK07940</td>\n<td>UK08693</td>\n<td></td>\n<td>UK08695</td>\n</tr>\n<tr>\n<td>PK08886</td>\n<td>UK08826</td>\n<td>UK08827</td>\n<td>UK08828</td>\n</tr>\n<tr>\n<td>PK09261</td>\n<td>UK09653</td>\n<td>UK09655</td>\n<td>UK09657</td>\n</tr>\n<tr>\n<td>PK10316</td>\n<td>UK09926</td>\n<td>UK09928</td>\n<td>UK09930</td>\n</tr>\n<tr>\n<td>PK10355</td>\n<td>UK06158</td>\n<td>UK06164</td>\n<td>UK06191</td>\n</tr>\n<tr>\n<td>PK12514</td>\n<td>UK07773</td>\n<td>UK07775</td>\n<td>UK07777</td>\n</tr>\n<tr>\n<td>PK12866</td>\n<td>UK09432</td>\n<td>UK09434</td>\n<td>UK09436</td>\n</tr>\n<tr>\n<td>PK13983</td>\n<td>UK10285</td>\n<td>UK10321</td>\n<td>UK10339</td>\n</tr>\n<tr>\n<td>PK15286</td>\n<td>UK09726</td>\n<td></td>\n<td>UK09727</td>\n</tr>\n<tr>\n<td>PK15984</td>\n<td>UK09861</td>\n<td>UK09863</td>\n<td>UK09865</td>\n</tr>\n<tr>\n<td>PK17443</td>\n<td>UK14471</td>\n<td>UK14494</td>\n<td>UK14501</td>\n</tr>\n<tr>\n<td>PK19580</td>\n<td>UK14262</td>\n<td>UK14264</td>\n<td>UK14266</td>\n</tr>\n<tr>\n<td>PK20237</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>PK21002</td>\n<td>UK13705</td>\n<td>UK13707</td>\n<td>UK13709</td>\n</tr>\n<tr>\n<td>PK25270</td>\n<td>UK15040</td>\n<td>UK15041</td>\n<td>UK15042</td>\n</tr>\n<tr>\n<td>PK26240</td>\n<td>UK15918</td>\n<td>UK15920</td>\n<td>UK15922</td>\n</tr>\n<tr>\n<td>PK26914</td>\n<td>UK16732</td>\n<td>UK16734</td>\n<td>UK16736</td>\n</tr>\n<tr>\n<td>PK28745</td>\n<td>UK22550</td>\n<td>UK22552</td>\n<td>UK22554</td>\n</tr>\n<tr>\n<td>PK29714</td>\n<td>UK17801</td>\n<td>UK17802</td>\n<td>UK17803</td>\n</tr>\n<tr>\n<td>PK30620</td>\n<td>UK18883</td>\n<td>UK18885</td>\n<td>UK18887</td>\n</tr>\n<tr>\n<td>PK30719</td>\n<td>UK23198</td>\n<td>UK23199</td>\n<td>UK23200</td>\n</tr>\n<tr>\n<td>PK31375</td>\n<td>UK20570</td>\n<td>UK20572</td>\n<td>UK20574</td>\n</tr>\n<tr>\n<td>PK31469</td>\n<td>UK18370</td>\n<td>UK18372</td>\n<td>UK18374</td>\n</tr>\n<tr>\n<td>PK39957</td>\n<td>UK26346</td>\n<td>UK26347</td>\n<td>UK26348</td>\n</tr>\n<tr>\n<td>APAR</td>\n<td>z/OS PTF</td>\n<td>VM PTF</td>\n<td>VSE PTF</td>\n</tr>\n<tr>\n<td>--------</td>\n<td>----------</td>\n<td>--------</td>\n<td>---------</td>\n</tr>\n<tr>\n<td>PK40271</td>\n<td>UK25670</td>\n<td>UK25671</td>\n<td>UK25672</td>\n</tr>\n<tr>\n<td>PK40813</td>\n<td>UK30719</td>\n<td>UK30720</td>\n<td>UK30721</td>\n</tr>\n<tr>\n<td>PK41381</td>\n<td>UK24329</td>\n<td>UK24331</td>\n<td>UK24333</td>\n</tr>\n<tr>\n<td>PK42140</td>\n<td>UK25273</td>\n<td>UK25274</td>\n<td>UK25275</td>\n</tr>\n<tr>\n<td>PK42414</td>\n<td>UK25976</td>\n<td>UK26024</td>\n<td>UK26038</td>\n</tr>\n<tr>\n<td>PK43326</td>\n<td>UK24451</td>\n<td>UK24452</td>\n<td>UK24453</td>\n</tr>\n<tr>\n<td>PK43386</td>\n<td>UK27503</td>\n<td>UK27504</td>\n<td>UK27505</td>\n</tr>\n<tr>\n<td>PK45696</td>\n<td>UK28814</td>\n<td>UK28815</td>\n<td>UK28816</td>\n</tr>\n<tr>\n<td>PK46123</td>\n<td>UK26778</td>\n<td>UK26779</td>\n<td>UK26780</td>\n</tr>\n<tr>\n<td>PK47176</td>\n<td>UK27004</td>\n<td>UK27005</td>\n<td>UK27006</td>\n</tr>\n<tr>\n<td>PK50735</td>\n<td>UK31331</td>\n<td>UK31340</td>\n<td>UK31384</td>\n</tr>\n<tr>\n<td>PK56760</td>\n<td>UK34422</td>\n<td>UK34423</td>\n<td>UK34424</td>\n</tr>\n</tbody>\n</table>\nAppendix B. Create Product Parameter File (PPF) override (z/VM)\n\nThis section provides information to help you create a product parameter file (PPF) override. The example used in this section shows how to change the shared file system (SFS) file pool where HLASM Toolkit Feature files reside.\n\nNote: Do not modify the product supplied P696234K $PPF or P696234K PPF files to change the file pool name or any other installation parameters. If the P696234K $PPF file is serviced, the existing $PPF file will be replaced, and any changes to that file will be lost; by creating your own $PPF override, your updates will be preserved.\n\nThe following process describes changing the default file pool name, VMSYS, to MYPOOL1:\n\n1. Create a new $PPF override file, or edit the override file created via the 'Make Override Panel' function.\n\n Command | Explanation\n --------|--------------------------------------------------\n xedit overname $PPF fm2 | * overname is the PPF override file name (such as “myHLASM”) that you want to use.\n | * fm is an appropriate file mode. If you create this file yourself, specify a file mode of A.\n\n If you modify an existing override file, specify a file mode of A or D, based on where the file currently resides (A being the file mode of a R/W 191 minidisk, or equivalent; D, that of the MAINT 51D minidisk).\n\n2. Create (or modify as required) the Variable Declarations (:DCL.) section for the HLASMSFS override area, so that it resembles the :DCL. section shown below. This override is used for the installation of HLASM Toolkit Feature.\n\n :OVERLST. HLASMSFS\n *\n *===================================================================\n * Override Section for Initial Installation (Using SFS Directories) *\n *===================================================================\n :HLASMSFS. HLASMSFS P696234K\n :DCL. REPLACE\n &191 DIR MYPOOL1:P696234K.\n &SAMPZ DIR MYPOOL1:P696234K.HLASMTL.LOCAL\n &DELTZ DIR MYPOOL1:P696234K.HLASMTL.DELTA\n &APPLX DIR MYPOOL1:P696234K.HLASMTL.APPLYALT\n &APPLZ DIR MYPOOL1:P696234K.HLASMTL.APPLYPROD\n &BLD0Z DIR MYPOOL1:P696234K.HLASMTL.TBUILD\n &BAS1Z DIR MYPOOL1:P696234K.HLASMTL.OBJECT\n &HLAID1 USER P696234K\n :EDCL.\n :END.\n *\n (This override replaces the :DCL. section of the HLASMSFS override area of the P696234K $PPF file.)\n\n3. If your $PPF override file was created on the A disk, copy it to file mode D—the Software Inventory minidisk (MAINT 51D). Then erase it from filemode\nCreate Product Parameter File (PPF) override (z/VM)\n\nA.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>copyfile overname $PPF fm = = d (olddate)</td>\n<td>Move PPF file to software inventory disk.</td>\n</tr>\n<tr>\n<td>erase overname $PPF fm</td>\n<td>Erase redundant file on fm disk.</td>\n</tr>\n</tbody>\n</table>\n\nOptions:\n\nOLDDATE\nUse the date and time on the input file as the date and time of last update of the output file.\n\n4. Compile your changes to create the usable overname PPF file.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Explanation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>vmfppf overname HLASMSFS</td>\n<td>overname is the file name of your $PPF override file.</td>\n</tr>\n</tbody>\n</table>\n\nNow that the overname PPF file has been created, you should specify overname instead of P696234K as the PPF name for those VMSES/E commands that require a PPF name.\nAppendix C. Planning for installing Program Understanding Tool on Windows\n\nThis section contains the following planning information to help you properly install Program Understanding Tool on Windows®:\n\n- Worksheet\n- Verify workstation requirements\n- Verify required workstation software\n- Host connectivity\n\nWorksheet: Planning for installing Program Understanding Tool on Windows\n\nBefore you begin the installation, you should:\n\n__ 1. Verify workstation requirements. Refer to “Verify workstation requirements.”\n__ 2. Verify that required software is at the level needed. Refer to “Verify workstation software.”\n__ 3. Verify connection to Host. Refer to “Verify host connectivity.”\n\nVerify workstation requirements\n\nThe following hardware requirements must be satisfied to use Program Understanding Tool:\n\n- Intel™ 80486-based 75Mhz processor or faster\n- 16 megabytes (16 MB) of memory (RAM) or more\n- 20 megabytes (20 MB) of available hard disk space\n- A communications package that can download host files\n- An SVGA display configured to display at least 256 colors\n\nVerify workstation software\n\nThe following software requirements must be satisfied to use Program Understanding Tool:\n\n- Windows XP or above.\n- Windows Vista.\n- A program capable of downloading binary files from a host system running z/OS, z/VM, or z/VSE, for example, Personal Communications for Windows.\n\nVerify host connectivity\n\nTo install Program Understanding Tool, files are downloaded from the host.\n\nUseful publications\n\nFor information on Program Understanding Tool, refer to HLASM Toolkit Feature User’s Guide.\n\nProgram Understanding Tool also contains extensive online help, which is accessible once the tool is running.\nAppendix D. Installing Program Understanding Tool on Windows\n\nThis section contains the following instructions to install Program Understanding Tool on Windows:\n\n- Worksheet\n- Prepare for installation\n- Download the product\n- Start the install\n- Verify successful installation\n\nWorksheet: Installing Program Understanding Tool on Windows\n\nBefore you begin the installation, you should:\n\n__ 1. Prepare for Installation. Refer to “Step 1: Prepare for installation.”\n__ 2. Download the Product. Refer to “Step 2: Download the product files” on page 86.\n__ 3. Start the Install. Refer to “Step 3: Start the install” on page 88.\n\nStep 1: Prepare for installation\n\nDownload product files. These files are the compressed files which make up the product. They are binary files.\n\nPreparing from z/OS\n\n1. Select a 3270 Emulation session and logon onto TSO.\n2. Ensure the session is left with a TSO READY prompt.\n\nPreparing from z/VM\n\n1. Select a 3270 Emulation session.\n2. Logon onto user P696234K.\n3. Establish the correct minidisk order.\n\n The VMFSETUP command accesses all the required disks or SFS directories to establish the needed CMS filemodes.\n Issue the following command:\n\n ```vmfssetup p696234k {hlasm|hlasmSfs}```\n\n `P696234K` is the PPF that is shipped with Program Understanding Tool. If you have your own PPF override, substitute your PPF name for P696234K.\n\n Use HLASM if the Program Understanding Tool is installed on a minidisk. Use HLASMFS if Program Understanding Tool is installed in SFS.\n\n4. The download process using the RECEIVE command is prone to interruption by messages being sent to the z/VM userid being used to download the files. To minimize this impact, issue the following commands:\n\n ```query set``` to display the status of many SET command functions. Please note the values for MSG, IMSG and SMSG.\nStep 1: Prepare for installation\n\n**SET MSG OFF**\nindicates whether messages sent from other users by means of the CP MESSAGE command are to be displayed. ON specifies that messages are displayed. OFF specifies that messages are not displayed.\n\n**SET IMSG OFF**\nindicates whether informational messages associated with certain CP commands are to be displayed. ON specifies that informational responses are displayed. OFF specifies that the responses are not displayed.\n\n**SET SMSG OFF**\nspecifies whether a virtual machine is receiving special messages. OFF indicates the virtual machine cannot receive special messages. ON indicates the virtual machine can receive special messages.\n\n5. Ensure the session is left with a blank CMS screen\n\nPreparing from z/VSE\n\n1. Sign on to the z/VSE host and switch to file transfer mode by doing one of the following:\n • Escape to CICS® (PF6/PF9) if you are allowed to do so.\n • If you are an administrator, select fast path 3-8-6.\n • If you are a programmer, select fast path 5-9-6.\n\nWorkstations should be in DFT mode with the Extended Data Stream (EXTDS) feature for each device associated with a host session. This is done in the CICS terminal control table (TCT). If you are unsure what mode your session is in, use the CICS/VSE® transaction INWQ to determine the mode of your 3270 session.\n\nStep 2: Download the product files\n\nThe syntax of the following RECEIVE commands will work with Communications Manager/2 or Personal Communications/3270.\n\n**Downloading from z/OS**\n\n1. Create a temporary directory where you will be downloading the compressed files used to install the product.\n\n2. Download the following members from the HLASM Toolkit target library as binary files:\n ```\n '<HLQ>SASMPUT2(ASMWREAD)' \n '<HLQ>SASMPUT2(ASMPUTW)' \n ```\n where <HLQ> is the high level qualifier (HLQ) for the partitioned data set which holds the member in binary form.\n\n Download member ASMWREAD as READ.ME and download member ASMPUTW as ASMPUTW.EXE.\n\n**Downloading from z/VM**\n\n1. Create a temporary directory where you will be downloading the compressed files used to install the product.\nStep 2: Download the product files\n\n2. Download the following CMS files from the HLASM Toolkit production disk (P696234K.29e) as binary files:\n ASMREAD BASEPF11\n ASMPUTW BASEPF11\n Download file ASMREAD BASEPF11 as READ.ME and download file ASMPUTW BASEPF11 as file ASMPUTW.EXE.\n\nDownloading from z/VSE\n\n1. Create a temporary directory where you will be downloading the product files used to install the product.\n2. Download the following .W books from the HLASM Toolkit library as binary files:\n ASMREAD.W\n ASMPUTW.W\n Download member ASMREAD.W as READ.ME and download member ASMPUTW.W as ASMPUTW.EXE.\n To do this:\n a. Open a Command Prompt session.\n b. Change to the temporary directory.\n Enter:\n CD \\<P>\n where <P> is the temporary directory.\n c. Receive the READ.ME file by entering:\n RECEIVE <P>READ.ME <S>:ASMREAD W\n (FILE=LIB L=<LIB> S=<SUBLIB> BINARY\n Receive the ASMPUTW.EXE file by entering:\n RECEIVE <P>ASMPUTW.EXE <S>:ASMPUTW W\n (FILE=LIB L=<LIB> S=<SUBLIB> BINARY\n where\n <P> is the path name where you want to receive the product files. When you enter the directory, add a trailing back slash (\\).\n <S> is the emulator session which you want to use to download the Installation file.\n <LIB> is the name of the library where Program Understanding Tool is installed.\n <SUBLIB> is the name of the sublibrary where Program Understanding Tool is installed.\n\nExample:\nTo receive the product files from host session A to the path C:\\TEMP from PRD2.PROD, enter:\nRECEIVE C:\\TEMP\\READ.ME A:ASMREAD W\n (FILE=LIB L=PRD2 S=PROD BINARY\nRECEIVE C:\\TEMP\\ASMPUTW.EXE A:ASMPUTW W\n (FILE=LIB L=PRD2 S=PROD BINARY\nStep 3: Start the install\n\nIn the temporary directory where you downloaded the two Program Understanding Tool files, select the file ASMPUT.EXE to extract the rest of the Program Understanding Tool files into the same directory.\n\nIn the same directory, now select SETUP.EXE to install Program Understanding Tool, providing appropriate answers to the questions. This will install Program Understanding Tool on your PC.\n\nNote that, as installed, the Program Understanding Tool toolbar buttons do not work on Windows 2000 or XP systems, and above. To resolve this, right-click on the Program Understanding Tool icon, and select Properties > Compatibility. Select Run this program in compatibility mode for: and select Windows 95 from the menu. Select Apply and then OK. Now the toolbar buttons should work.\n\nRead the READ.ME file using a text editor such as NOTEPAD, for other information you need about using Program Understanding Tool, and carry out the instructions contained in this file.\n\nStep 4: Verify successful installation\n\nTo verify the successful installation of Program Understanding Tool, invoke Program Understanding Tool by using the START button, selecting PROGRAMS and clicking on HLASM Program Understanding Tool.\n\nProgram Understanding Tool is now installed and ready for use.\nAppendix E. Maintaining Program Understanding Tool on Windows\n\nThis section contains instructions for maintaining, and for removing, Program Understanding Tool on Windows.\n\nMaintaining Program Understanding Tool\n\nService for Program Understanding Tool will first be applied on the host, and then the new version of Program Understanding Tool downloaded to Windows.\n\nTo maintain this product:\n1. Uninstall this product on the workstation. See \"Uninstalling Program Understanding Tool from Windows.\"\n2. Apply service on the host. The normal service stream via PTFs will be applied to the parts on the host.\n3. Re-install this product on the workstation, as described in Appendix D, \"Installing Program Understanding Tool on Windows,\" on page 85.\n\nUninstalling Program Understanding Tool from Windows\n\nTo remove Program Understanding Tool carry out the following tasks.\n\nTasks\n1. Ensure you have a current backup of this product.\n2. Save user files.\n You will need to copy any files that you have stored in the \\DATA subdirectory to another directory, and then delete these files from the \\DATA directory, before you can uninstall the product.\n3. From the toolbar, select Start, Settings, Control Panel, Add/Remove Programs. From the list of software, select ASMPUT, and click Add/Remove, then click Yes.\nUninstalling Program Understanding Tool from Windows\nBibliography\n\nHigh Level Assembler Publications\n\nHLASM General Information GC26-4943\nHLASM Installation and Customization Guide SC26-3494\nHLASM Language Reference SC26-4940\nHLASM Licensed Program Specifications GC26-4944\nHLASM Programmer’s Guide SC26-4941\n\nHLASM Toolkit Feature Publications\n\nHLASM Toolkit Feature User’s Guide GC26-8710\nHLASM Toolkit Feature Debug Reference Summary GC26-8712\nHLASM Toolkit Feature Interactive Debug Facility User’s Guide GC26-8709\nHLASM Toolkit Feature Installation and Customization Guide GC26-8711\n\nRelated Publications (Architecture)\n\nEnterprise Systems Architecture/390 Principles of Operation SA22-7201\nEnterprise Systems Architecture/370 Principles of Operation SA22-7200\nSystem/370 Principles of Operation GA22-7000\nSystem/370 Extended Architecture Principles of Operation SA22-7085\nz/Architecture Principles of Operation SA22-7832\n\nRelated Publications for z/OS\n\nz/OS:\n\nz/OS MVS JCL Reference SA22-7597\nz/OS MVS JCL User’s Guide SA22-7598\nz/OS MVS Programming: Assembler Services Guide SA22-7605\nz/OS MVS Programming: Assembler Services Reference, Volumes 1 and 2, SA22-7606, SA22-7607\nz/OS MVS Programming: Authorized Assembler Services Guide SA22-7608\nz/OS MVS Programming: Authorized Assembler Services Reference, Volumes 1 - 4, SA22-7609 - SA22-7612\nz/OS MVS Program Management: User’s Guide and Reference SA22-7643\nz/OS MVS System Codes SA22-7626\nz/OS MVS System Commands SA22-7627\nz/OS MVS System Messages, Volumes 1 - 10, SA22-7631 - SA22-7640\nz/OS Communications Server: SNA Programming SC31-8829\n\nOS/390:\n\nOS/390 MVS System Messages, Volumes 1 - 5, GC28-1784 - GC27-1788\n\nUNIX System Services:\n\nz/OS UNIX System Services User’s Guide SA22-7801\n\nDFSMS/MVS:\n\nz/OS DFSMS Program Management SC27-1130\nz/OS DFSMSdfp Utilities SC26-7414\n\nTSO/E (z/OS):\n\nz/OS TSO/E Command Reference SA22-7782\nTSO/E (OS/390):\n\nOS/390 TSO/E Command Reference SC28-1969\nSMP/E (z/OS):\n\nSMP/E Messages, Codes, and Diagnosis GA22-7770\nSMP/E Reference SA22-7772\nSMP/E User’s Guide SA22-7773\nSMP/E (OS/390):\n\nOS/390 SMP/E Messages and Codes SC28-1738\nOS/390 SMP/E Reference SC28-1806\nOS/390 SMP/E User’s Guide SC28-1740\n\nRelated Publications for z/VM\n\nz/VM:\n\nVMSES/E Introduction and Reference GC24-6130\nz/VM: Service Guide GC24-6117\nz/VM: CMS Commands and Utilities Reference SC24-6073\nz/VM: CMS File Pool Planning, Administration, and Operation SC24-6074\n\n© Copyright IBM Corp. 1997, 2008\nRelated Publications for z/VSE\n\n- z/VSE: Guide to System Functions SC33-8233\n- z/VSE: Administration SC33-8224\n- z/VSE: Installation SC33-8222\n- z/VSE: Planning SC33-8221\n- z/VSE: System Control Statements SC33-8225\n- z/VSE: Messages and Codes, Vol.1 SC33-8226\n- z/VSE: Messages and Codes, Vol.2 SC33-8227\n- z/VSE: Messages and Codes, Vol.3 SC33-8228\n- REXX/VSE Reference SC33-6642\n- REXX/VSE User’s Guide SC33-6641\nGlossary\n\nThis glossary defines terms and abbreviations that are used in this book. If you do not find the term you are looking for refer to the index, to the glossary of the appropriate high-level language (HLL) manual, or to the IBM Dictionary of Computing, New York: McGraw-Hill, 1994.\n\nA\n\nabend. Abnormal end of application.\naccept. An SMP/E process that moves distributed code and programs to the distribution libraries.\nactivate. To make a program available for use.\naddressing mode (AMODE). An attribute that refers to the address length that a routine is prepared to handle upon entry. Addresses may be 24 or 31 bits long.\naddress space. Domain of addresses that are accessible by an application.\nAMODE. Addressing mode.\nAPAR. Authorized program analysis report.\nauthorized program analysis report (APAR). A request for correction of a problem caused by a defect in a current unaltered release of a program.\nauthorized program facility (APF). The authorized program facility (APF) is a facility that an installation manager uses to protect the system. In MVS, certain system functions, such as all or part of some SVCs, are sensitive; their use must be restricted to users who are authorized. An authorized program is one that executes in supervisor state, or with APF authorization.\nauxiliary file. In CMS, a file that contains a list of file types of update files to be applied to a particular source file.\n\nB\n\nbase. The core product, upon which features may be separately ordered and installed.\nbatch. Pertaining to activity involving little or no user action. Contrast with interactive.\nbyte. The basic unit of storage addressability, usually with a length of 8 bits.\n\nC\n\ncataloged procedure. A set of control statements placed in a library and retrievable by name.\nCBPDO. Custom-Built Product Delivery Offering.\nCE. IBM customer engineer.\nCLIST. TSO command list.\nCMS. Conversational monitor system.\ncompiler options. Keywords that can be specified to control certain aspects of compilation. Compiler options can control the nature of the load module generated by the compiler, the types of printed output to be produced, the efficient use of the compiler, and the destination of error messages.\ncomponent. (1) Software that is part of a functional unit. (2) A set of modules that performs a major function within a system.\ncondition code. A code that reflects the result of a previous input/output, arithmetic, or logical operation.\ncontrol block. A storage area used by a computer program to hold control information.\ncontrol file. In CMS, a file that contains records that identify the updates to be applied and the macrolibraries, if any, needed to assemble a particular source program.\ncontrol program (CP). A computer program designed to schedule and to supervise the execution of programs of a computer system.\ncontrol section (CSECT). The part of a program specified by the programmer to be a relocatable unit, all elements of which are to be loaded into adjoining main storage locations.\ncontrol statement. (1) In programming languages, a statement that is used to alter the continuous sequential execution of statements; a control statement can be a conditional statement, such as IF, or an imperative statement, such as STOP. (2) In JCL, a statement in a job that is used in identifying the job or describing its requirements to the operating system.\nconversational monitor system (CMS). A virtual machine operating system that provides general interactive time sharing, problem solving, and program development capabilities, and operates only under the control of the VM/370 control program.\n\n© Copyright IBM Corp. 1997, 2008\n**corrective maintenance.** Maintenance performed specifically to overcome existing problems.\n\n**CP command.** In VM, a command by which a terminal user controls his or her virtual machine. The VM/370 control program commands are called CP commands.\n\n**CPPL.** Command processor parameter list.\n\n**CP privilege class.** In VM, one or more classes assigned to a virtual machine user in the user’s VM directory entry; each privilege class allows access to a logical subset of the CP commands.\n\n**CSI.** Consolidated software inventory data set. See SMPCSI.\n\n**CSECT.** Control section.\n\n**cumulative service tape.** A tape sent with a new function order, containing all current PTFs for that function.\n\n**Custom-Built Installation Process Offering (CBIPO).** A CBIPO is a tape that has been specially prepared with the products (at the appropriate release levels) requested by the customer. A CBIPO simplifies installing various products together.\n\n**Custom-Built Product Delivery Offering (CBPDO).** A CBPDO is a tape that has been specially prepared for installing a particular product and the related service requested by the customer. A CBPDO simplifies installing a product and the service for it.\n\n**D**\n\n**data definition name (DDNAME).** The logical name of a file within an application. The DDNAME provides the means for the logical file to be connected to the physical file.\n\n**data set.** On MVS, a named collection of related data records that is stored and retrieved by an assigned name. Equivalent to a CMS file.\n\n**data set name (dsname).** The data set name on the DD statement in the JCL or the dsname operand of the TSO ALLOC command.\n\n**DBCS.** Double-byte character set.\n\n**DDDEF.** Dynamic data definition.\n\n**DDNAME.** Data definition name.\n\n**default.** A value that is used when no alternative is specified.\n\n**DD statement.** In MVS, connects the logical name of a file and the physical name of the file.\n\n**DELTA disk.** In VM, the virtual disk that contains program temporary fixes (PTFs) that have been installed but not merged.\n\n**distribution libraries.** IBM-supplied partitioned data sets on tape containing one or more components that the user restores to disk for subsequent inclusion in a new system.\n\n**distribution medium.** The medium on which software is distributed to the user; for example, 9-track magnetic tape, tape cartridge.\n\n**distribution zone.** In SMP/E, a group of VSAM records that describe the SYSMODs and elements in the distribution libraries.\n\n**DITTO utility.** Data Interfile Transfer, Testing and Operations utility.\n\n**double-byte character set (DBCS).** A collection of characters represented by a 2-byte code.\n\n**driving system.** The system used to install the program. Contrast with target system.\n\n**dsname.** Data set name.\n\n**dynamic data definition (DDDEF).** The process of defining a data set and allocating auxiliary storage space for it while, rather than before, a job step executes.\n\n**dynamic storage.** Storage acquired as needed at run time. Contrast with static storage.\n\n**E**\n\n**ECMODE.** Extended control mode.\n\n**executable program.** (1) A program that has been link-edited and therefore can run in a processor. (2) The set of machine language instructions that constitute the output of the compilation of a source program.\n\n**Extended control mode (ECMODE).** A mode in which all features of a System/370 computing system, including dynamic address translation, are operational.\n\n**Extended Service Option (ESO).** A service option that gives a customer all the new fixes for problems in IBM licensed programs that operate under that customer’s operating system.\n\n**F**\n\n**feature.** A part of an IBM product that may be ordered separately by a customer.\n\n**feature number.** A four-digit code used by IBM to process hardware and software orders.\nfile. A named collection of related data records that is stored and retrieved by an assigned name. Equivalent to an MVS data set.\n\nFILEDEF. File definition statement.\n\nfile definition statement (FILEDEF). In CMS, connects the logical name of a file and the physical name of a file.\n\nfix. A correction of an error in a program, usually a temporary correction or bypass of defective code.\n\nFMID. Function modification identifier.\n\nfunction. A routine that is invoked by coding its name in an expression. The routine passes a result back to the invoker through the routine name.\n\nfunction modification identifier (FMID). The value used to distinguish separate parts of a product. A product tape or cartridge has at least one FMID.\n\nIBM customer engineer (CE). An IBM service representative who performs maintenance services for IBM hardware.\n\nIBM program support representative (PSR). An IBM service representative who performs maintenance services for IBM software at a centralized IBM location.\n\nIBM service representative. An individual in IBM who performs maintenance services for IBM products or systems.\n\nIBM Software Distribution (ISD). The IBM department responsible for software distribution.\n\nIBM Support Center. The IBM department responsible for software service.\n\nIBM systems engineer (SE). An IBM service representative who performs maintenance services for IBM software in the field.\n\ninitial program load (IPL). (1) The initialization procedure that causes an operating system to commence operation. (2) The process by which a configuration image is loaded into storage, as at the beginning of a work day or after a system malfunction or as a means to access updated parts of the system. (3) The process of loading system programs and preparing a system to run jobs.\n\ninline. Sequential execution of instructions, without branching to routines, subroutines, or other programs.\n\nIPL. Initial program load.\n\ninteractive. Pertaining to a program or system that alternately accepts input and responds. In an interactive system, a constant dialog exists between user and system. Contrast with batch.\n\nInteractive Interface. A series of panels, allowing the user to use the facilities of the VSE/ESA operating. This interface runs within CICS/VSE.\n\nISD. IBM Software Distribution.\n\nJ\n\nJCL. Job control language.\n\nJCLIN data. The JCL statements associated with the ++JCLIN statement or saved in the SMPJCLIN data set. They are used by SMP/E to update the target zone when the SYSMOD is applied. Optionally, SMP/E can use the JCLIN data to update the distribution zone when the SYSMOD is accepted.\n\nJES. Job Entry Subsystem\n\nJob Entry Subsystem. A system facility for spooling, job queueing, and managing the scheduler work area.\n\njob control language (JCL). A sequence of commands used to identify a job to an operating system and to describe a job’s requirements.\n\njob step. You enter a program into the operating system as a job step. A job step consists of the job control statements that request and control execution of a program and request the resources needed to run the program. A job step is identified by an EXEC statement. The job step can also contain data needed by the program. The operating system distinguishes job control statements from data by the contents of the record.\n\nL\n\nlibrarian. In VSE, the set of programs that maintains, services, and organizes the system and private libraries.\n\nlibrary. A collection of functions, subroutines, or other data.\n\nlink pack area (LPA). In MVS, an area of main storage containing reenterable routines from system libraries. Their presence in main storage saves loading time when a reenterable routine is needed.\n\nlinkage editor. A program that resolves cross-references between separately assembled object modules and then assigns final addresses to create a single relocatable load module. The linkage editor then stores the load module in a program library in main storage.\nlink-edit. To create a loadable computer program by means of a linkage editor.\n\nload module. An application or routine in a form suitable for execution. The application or routine has been compiled and link-edited; that is, address constants have been resolved.\n\nlogical saved segment. A portion of a physical saved segment that CMS can manipulate. Each logical saved segment can contain different types of program objects, such as modules, text files, execs, callable services libraries, language repositories, user-defined objects, or a single minidisk directory. A system segment identification file (SYSTEM SEGID) associates a logical saved segment to the physical saved segment in which it resides. See physical saved segment and saved segment.\n\nLPA. Link pack area.\n\nmaintain system history program (MSHP). In VSE, a program used for automating and controlling various installation, tailoring, and service activities for a VSE system.\n\nMCS. Modification control statement\n\nminidisk. In VM, all, or a logical subdivision of, a physical disk storage device that has its own address, consecutive storage space for data, and an index or description of stored data so that the data can be accessed. Synonymous with virtual disk.\n\nmodule. A language construct that consists of procedures or data declarations and can interact with other such constructs.\n\nMSHP. Maintain system history program.\n\nMVS. Multiple Virtual Storage operating system.\n\nN\n\nNamed Saved System. A copy of an operating system that a user has named and saved in a file. The user can load the operating system by its name, which is more efficient than loading it by device number.\n\nnational language support (NLS). Translation requirements affecting parts of licensed programs; for example, translation of message text and conversion of symbols specific to countries.\n\nNLS. National language support.\n\nnonexecutable components. Components of a product that cannot be run.\n\nnon reentrant. A program that cannot be shared by multiple users.\n\nnonreenterable. See non reentrant.\n\nNSS. named saved system\n\nO\n\nobject code. Output from a compiler or assembler which is itself executable machine code or is suitable for processing to produce executable machine code.\n\nobject deck. Synonymous with object module, text deck.\n\nobject module. A portion of an object program suitable as input to a linkage editor. Synonymous with text deck, object deck.\n\nonline. (1) Pertaining to a user’s ability to interact with a computer. (2) Pertaining to a user’s access to a computer via a terminal.\n\noperating system. Software that controls the running of programs; in addition, an operating system may provide services such as resource allocation, scheduling, input/output control, and data management.\n\nP\n\nparameter. Data items that are received by a routine.\n\npartition. A fixed-size division of storage.\n\nphase. In VSE, the smallest complete unit of executable code that can be loaded into virtual storage.\n\nphysical saved segment. One or more pages of storage that have been named and retained on a CP-owned volume (DASD). When created, it can be loaded within a virtual machine’s address space or outside a virtual machine’s address space. Multiple users can load the same copy. A physical saved segment can contain one or more logical saved segments. A system segment identification file (SYSTEM SEGID) associates a physical saved segment to its logical saved segments. See logical saved segment and saved segment.\n\npreventive maintenance. Maintenance performed specifically to prevent problems from occurring.\n\npreventive service planning (PSP). The online repository of program temporary fixes (PTFs) and other service information. This information could affect installation.\n\nprocedure. A named block of code that can be invoked, usually via a call.\n\nprocedure library (PROCLIB). A program library in direct access storage with job definitions. The\nreader/interpreter can be directed to read and interpret a particular job definition by an execute statement in the input stream.\n\n**PROCLIB.** Procedure library.\n\n**program level.** The modification, release, version, and fix level of a product.\n\n**program number.** The seven-digit code (in the format xxxx-xxx) used by IBM to identify each program product.\n\n**program temporary fix (PTF).** A temporary solution or bypass of a problem diagnosed by IBM as resulting from a defect in a current unaltered release of the program.\n\n**PSP.** Preventive service planning.\n\n**PSR.** IBM program support representative.\n\n**PTF.** Program temporary fix.\n\n**Q**\n\n**qualifier.** A modifier that makes a name unique.\n\n**R**\n\n**reentrant.** The attribute of a routine or application that allows more than one user to share a single copy of a load module.\n\n**reenterable.** See reentrant\n\n**relative file tape (RELFILE tape).** A standard label tape made up of two or more files. It contains a file of the MCSes for one or more function SYSMODs and one or more relative files containing unloaded source data sets and unloaded, link-edited object data sets at the distribution library level. A relative file tape is one way of packaging SYSMODs, and is typically used for function SYSMODs.\n\n**relative files (RELFILES).** Files containing modification text and JCL input data associated with a SYSMOD.\n\n**RELFILES.** Relative files\n\n**RELFILE tape.** Relative file tape\n\n**relocatable load module.** On CMS, a combination of object modules having cross references resolved and prepared for loading into storage for execution.\n\n**residence mode (RMODE).** The attribute of a load module that specifies whether the module, when loaded, must reside below the 16MB virtual storage line or may reside anywhere in virtual storage.\n\n**resident modules.** A module that remains in a particular area of storage.\n\n**return code.** A code produced by a routine to indicate its success. It can be used to influence the execution of succeeding instructions.\n\n**RIM.** Related installation materials\n\n**RMODE.** Residence mode.\n\n**run.** To cause a program, utility, or other machine function to be performed.\n\n**S**\n\n**save area.** Area of main storage in which contents of registers are saved.\n\n**SBCS.** Single-byte character set.\n\n**SE.** IBM systems engineer.\n\n**service level.** The modification level, release, version, and fix level of a program. The service level incorporates PTFs if there are any.\n\n**saved segment.** A segment of storage that has been saved and assigned a name. Saved segments can be physical saved segments that CP recognizes or logical saved segments that CMS recognizes. The segments can be loaded and shared among virtual machines, which helps use real storage more efficiently, or a private, nonshared copy can be loaded into a virtual machine. See logical saved segment and physical saved segment.\n\n**shared segment.** In VM, a feature of a saved system that allows one or more segments of reenterable code in real storage to be shared among many virtual machines.\n\n**shared storage.** An area of storage that is the same for each virtual address space. Because it is the same space for all users, information stored there can be shared and does not have to be loaded in the user region.\n\n**shared virtual area (SVA).** In VSE, a high address area of virtual storage that contains a system directory list (SDL) of frequently used phases, resident programs that can be shared between partitions, and an area for system support.\n\n**severity code.** A part of run-time messages that indicates the severity of the error condition (1, 2, 3, or 4).\n\n**single-byte character set (SBCS).** A collection of characters represented by a 1-byte code.\n\n**SMPCSI.** The SMP/E data set that contains information about the structure of a user’s system as well as information needed to install the operating system on a user’s system. The SMPCSI DD statement\nrefers specifically to the CSI that contains the global zone. This is also called the master CSI.\n\n**softcopy.** One or more files that can be electronically distributed, manipulated, and printed by a user.\n\n**software inventory disk.** In VM, the disk where the system level inventory files reside.\n\n**source code.** The input to a compiler or assembler, written in a source language.\n\n**source program.** A set of instructions written in a programming language that must be translated to machine language before the program can be run.\n\n**SREL.** System release identifier\n\n**statement.** In programming languages, a language construct that represents a step in a sequence of actions or a set of declarations.\n\n**sublibrary.** In VSE, a subdivision of a library.\n\n**SUBSET.** The value that specifies the function modifier (FMID) for a product level. It further specifies an entry in RETAIN* for a product level.\n\n**subsystem.** A secondary or subordinate system, or programming support, usually capable of operating independently of or asynchronously with a controlling system. Examples are CICS and IMS.\n\n**SVA.** Shared virtual area.\n\n**syntax.** The rules governing the structure of a programming language and the construction of a statement in a programming language.\n\n**SYSMOD.** System modification.\n\n**SYSMOD ID.** System modification identifier.\n\n**system abend.** An abend caused by the operating system’s inability to process a routine; can be caused by errors in the logic of the source routine.\n\n**text deck.** Synonym for object module, object deck.\n\n**time sharing option/extended (TSO/E).** An option on the operating system; for System/370, the option provides interactive time sharing from remote terminals.\n\n**TSO/E.** Time sharing option/extended.\n\n**U**\n\n**UCLIN.** In SMP/E, the command used to initiate changes to SMP/E data sets. Actual changes are made by subsequent UCL statements.\n\n**UPGRADE.** An alphanumeric identifier that specifies a product level.\n\n**user exit.** A routine that takes control at a specific point in an application.\n\n**USERMOD.** User modification.\n\n**user modification (USERMOD).** A change to product code that the customer initiates.\n\n**V**\n\n**virtual machine (VM).** (1) A functional simulation of a computer and its associated devices. Each virtual machine is controlled by a suitable operating system. (2) In VM, a functional equivalent of either a System/370 computing system or a System/370-Extended Architecture computing system.\n\n**VMFINS.** An installation aid supplied as part of VMSES/E to make installation on VM consistent.\n\n**VM Serviceability Enhancements Staged/Extended (VMSES/E).** A program product for installing and maintaining products on VM.\n\n**VMSES/E.** VM Serviceability Enhancements Staged/Extended.\n\n**VOLSER.** Volume serial number.\n\n**volume.** (1) A certain portion of data, together with its data carrier, that can be handled conveniently as a unit. (2) A data carrier mounted and demounted as a unit; for example, a reel of magnetic tape, a disk pack.\n\n**volume label.** An area on a standard label tape used to identify the tape volume and its owner. This area is the first 80 bytes and contains VOL 1 in the first four positions.\n\n**volume serial number (VOLSER).** A number in a volume label assigned when a volume is prepared for use in a system.\n\n**VSAM.** Virtual storage access method. A high-performance mass storage access method. Three\ntypes of data organization are available: entry sequenced data sets (ESDS), key sequenced data sets (KSDS), and relative record data sets (RRDS).\nNotices\n\nThis information was developed for products and services offered in the U.S.A.\n\nIBM may not offer the products, services, or features discussed in this document in other countries. Consult your local IBM representative for information on the products and services currently available in your area. Any reference to an IBM product, program, or service is not intended to state or imply that only that IBM product, program, or service may be used. Any functionally equivalent product, program, or service that does not infringe any IBM intellectual property right may be used instead. However, it is the user’s responsibility to evaluate and verify the operation of any non-IBM product, program, or service.\n\nIBM may have patents or pending patent applications covering subject matter described in this document. The furnishing of this document does not give you any license to these patents. You can send license inquiries, in writing, to:\n\nIBM Director of Licensing\nIBM Corporation\nNorth Castle Drive\nArmonk, NY 10504-1785\nU.S.A.\n\nLicensees of this program who wish to have information about it for the purpose of enabling: (i) the exchange of information between independently created programs and other programs (including this one) and (ii) the mutual use of the information which has been exchanged, should contact:\n\nIBM Corporation\nMail Station P300\n2455 South Road\nPoughkeepsie New York 12601-5400\nU.S.A.\n\nSuch information may be available, subject to appropriate terms and conditions, including in some cases, payment of a fee.\n\nThe licensed program described in this document and all licensed material available for it are provided by IBM under terms of the IBM Customer Agreement, IBM International Program License Agreement or any equivalent agreement between us.\n\nThe following paragraph does not apply to the United Kingdom or any other country where such provisions are inconsistent with local law: INTERNATIONAL BUSINESS MACHINES CORPORATION PROVIDES THIS PUBLICATION “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Some states do not allow disclaimer of express or implied warranties in certain transactions, therefore, this statement may not apply to you.\n\nThis information could include technical inaccuracies or typographical errors. Changes are periodically made to the information herein; these changes will be\nincorporated in new editions of the publication. IBM may make improvements and/or changes in the product(s) and/or the program(s) described in this publication at any time without notice.\n\nAny references in this information to non-IBM Web sites are provided for convenience only and do not in any manner serve as an endorsement of those Web sites. The materials at those Web sites are not part of the materials for this IBM product and use of those Web sites is at your own risk.\n\nIf you are viewing this information softcopy, the photographs and color illustrations may not appear.\n\n**Trademarks**\n\nThe following are trademarks of International Business Machines Corporation in the United States, or other countries, or both.\n\n<table>\n<thead>\n<tr>\n<th>IBM</th>\n<th>ProductPac</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>The IBM Logo</td>\n<td>RETAIN</td>\n</tr>\n<tr>\n<td>ibm.com</td>\n<td>REXX</td>\n</tr>\n<tr>\n<td>CICS</td>\n<td>S/390</td>\n</tr>\n<tr>\n<td>CICS/VSE</td>\n<td>System/370</td>\n</tr>\n<tr>\n<td>IBMLink</td>\n<td>VM/ESA</td>\n</tr>\n<tr>\n<td>IMS</td>\n<td>VTAM</td>\n</tr>\n<tr>\n<td>MVS</td>\n<td>z/OS</td>\n</tr>\n<tr>\n<td>OS/2</td>\n<td>z/VM</td>\n</tr>\n<tr>\n<td>POWER</td>\n<td>z/VSE</td>\n</tr>\n</tbody>\n</table>\n\nWindows is a registered trademark of Microsoft Corporation in the United States and other countries.\n\nIntel is a trademark of Intel Corporation in the U.S. and other countries.\n\nOther company, product, and service names may be trademarks or service marks of others.\nIndex\n\nSpecial characters\n\n$JBVEND 68\n$VAAST 68\n$VMFBLD $MSGLOG 50\n$VMFINS $MSGLOG message log 35, 39\n$VMFREC $MSGLOG 45\n\nNumerics\n\n181 tape virtual address 38\n3270 emulation 85\n3270 session 86\n3350 DASD 30\n3375 DASD 30\n3380 DASD 30, 57\n3390 DASD 30, 57\n3480 cartridge 4, 28, 56\n4mm cartridge 4\n5751-CS3 4\n6250 tape 4\n9345 DASD 30\n\nA\n\naccess VMSES/E programs 34\nadata 68\nadministrator 86\nALLOC 68\nalternate DELTA disk 46\napar 9, 10, 31, 59\nAPAR 21, 43, 71\nprerequisites 43\nservice tape 72\napply 17\napply check 17\napply message log 47\napplying maintenance 21, 43\napplying service checklist 21, 43\napplying service updates 21, 43\nbackup existing system 72\ninteractive interface 72\nretracing APARs and PTFs 72\nsteps required 71\nsystem history file 72\nusing the interactive interface 72\nASI 67\nASMPUTW 87\nASMTALOC job 16\nASMTAPL job 17\nASMTDDEF job 16\nASMTDEF 62\nASMTDRTF job 62\nASMTINST 66\nASMTINST job 66\nASMTITLP job 18\nASMTITLPSS 68\nASMTIIVP job 69\nASMTSAMP 50\nASMTVTOC job 62\nASMWREAD 87\nASMWTRCV job 16\nASMXREF VSAM catalogs 70\nassembler\noption 68\nauthorization 68\nautomated system initialization 67\n\nB\n\nbackup copy of HLASM Toolkit Feature (z/VM) 44\nbackup of HLASM Toolkit Feature (z/OS) 22\nbackup of HLASM Toolkit Feature (z/VSE) 72\nbasic material 56\nz/OS 4\nz/VM 28\nblocks, SFS 36\nblocksize 6\nbooks\nbasic publications 5, 29, 57\nbuild status messages 49\nbuild status table 39\n\nC\n\ncartridge 4, 28, 56\ncontents 56\nCBPDO 4, 9, 13\nRCVPDO RIM 8\ntape 10\ncheck apply 17\nchecklist\nfor Windows installation 85\nfor Windows installation planning 83\nfor z/OS installation planning 3\nfor z/VSE, installation planning 56\ninstallation for z/OS 14\ninstallation planning for z/VM 27\nz/VM installation 33\nCICS escape 86\nclear alternate apply disk 43, 45\nclear service 45\ncompiling PPF 48\ncomponent id 23, 52, 56\ncomponent name 23, 52, 56\nconcatenation 17\nconfiguration\nVTAM 69\nconsole message 64\ncopy service 43\ncopyfile 49\ncorrective service 44\ncumulative service tape 10, 28, 56, 59\ncurrent service viii\n\nD\n\ndasz 6\ndASD storage\nz/VM 30\ndASD Storage 57\ndefault library 58\ndelete fmids 8\ndelete product z/OS 23\nz/VM 52\nDELTA disk alternate 46\ndesktop 89\ndft 86\ndirectory 87\ndirectory entry location 36\ndirectory maintenance 36\ndIRMAINT 36\ndisassembler 40\ndisk order 44\ndistribution libraries 5, 16\ndistribution media 4, 28, 56\ndistribution tape 4, 28, 67\nDITTO DVT 62\ndocumentation\nHigh Level Assembler 91\ndocuments\nlist for z/OS 4\nlist for z/VM 28\ndownload 42, 70\ndownload, z/OS 86\ndownload, z/VM 86\ndownload, z/VSE 87\ndriving system 5\ndspace 15\ndTSECTAB 68\n\ne\n\nelectronic service 44\nemulator session 87\nenroll user 37\nEXEC 39, 40\nexit routines 68\nexternal label 4\nextra space 6\n\nF\n\nfast path 86\nFBA blocks 57\nfeature number 3, 4, 27, 28, 55, 56\nfile label 63\nfile mode 85\nfile transfer mode 86\nfilepool query 37\nfilepool references 37\nfmid 4, 8, 23\nFMID 3\nformat notation, description viii\nfunction modification ID 23\n\n© Copyright IBM Corp. 1997, 2008\nPTF (continued)\n\nservice tape, z/VSE 71\n\nPublications\n\nBasic, z/OS 5\nBasic, z/VM 29\nBasic, z/VSE 57\nHigh Level Assembler 91\nHLASM Toolkit 91\nHLASM Toolkit Feature 56\nMachine instructions 91\nUseful during install 61\nUseful during install, z/OS 11\nUseful during install, z/VM 31\nUseful during install, z/VSE 59\nz/OS 91\nz/VM 91\nz/VSE 59, 92\n\nService (continued)\n\nUpdates for z/VM 43\nUser ID for z/VM 44\nService level 10, 31, 59\nService, Program Understanding Tool 22, 52, 74\nSFS 85\nShared data set 6\nShared file system 29\ndirectories 30, 44\ndirectory create 37\ndirectory examples 37\nGRANT AUTHORITY 37\nNewread 37\nRead authority 37\nSpecific install steps 36\nSubdirectories 37\ntop directory 36\nUser ID 36\nWorkspace 36\n\nSMP/E\n\nACCEPT 22\nAPPLY 22\nAPPLY CHECK 22\nAPPLY REDO 21\ndata sets 7\ndirectories 3\ndirectories, level 6\nRECEIVE 22\nwork data sets 7\n\nSMP/IT\n\nSMP/IT 7\nSMP/IT 7\nSMP/IT 7\n\nSoftware inventory\n\nAccess disk 34, 44\nReapply local service 44\nShared file system access 29\nSoftwareXcel Extended 23, 75\nStacked items ix\nStandard labels 66, 67\nStorage\n\nDASD requirements 57\nSublibrary name, z/VSE 87\nSubset 9, 31, 58\nSubset ID 9, 31, 52, 59\nSubset ID 23, 75\nSVA 67\nSVA phases 67\nSyntax notation, description viii\nSyndata 68\nSyslib 17\nSystem delivery option 28\nSystem history file 57, 66, 67, 72\nSystem Modification Program Extended (SMP/E) 9\nSysut1 7\nSysut2 7\nsysut3 7\nSysut4 7\n\nTape\n\nTS696234 EXEC 50\n\nTape content 4, 28\nCumulative service 10, 28, 56, 59\n\nIndex 105\nuninstall Program Understanding Tool from Windows 89\nunique data set 6\nupdate build status table 49\nupdate, Program Understanding Tool 22, 52, 74\nupgrade 9, 31, 58\nvalue, z/OS 9\nvalue, z/VM 31, 52\nvalue, z/VSE 59\nUpgrade\nvalue, z/OS 23\nupgrade value 75\n\nV\nvendor exit 67\nSVA 67\nvendor exits 68\nverification 88\nafter service 22, 44\nASMTIVP job 18\nASMTIVPS 68\nEXEC 50\nsample output, z/VM 40\nverify applied service 74\nverify installation\nASMTIVPS 69\nvirtual tape address 38\nVMFAPP2120W 47\nVMFAPPLY 44\nVMFBLD 44\nVMFMRDSK 43\nVMFREC 44\nvmsetup 85\nVMFSETUP 44\nVMSES/E 29\n$VMFBLD $MSGLOG 50\n$VMFREC $MSGLOG 45\nalternate DELTA disk 46\napply message log 47\napply service 47\nbuild status messages 49\nclear alternate apply disk 45\ncommand syntax 43\ncompiling PPF 48\nlocal modifications 47\nmerged message log 46\nPLANINFO file 35\n\nVMSES/E (continued)\nPPF override 35, 39, 48\nrebuild serviced parts 50\nreceive message log 45\nreference manuals 43\nrequisite checking 35\nreview build message log 50\nreview message log 47\nupdate build status table 48, 49\nversion vector table (VVT) 47\nVMFAPP2120W 47\nVMFAPPLY 44\nVMFAPPLY PPF command 47\nVMFBLD PPF command 48, 49, 50\nVMFBLD rebuild serviced parts 44\nVMFBLD update build status table 44\nVMFCOPY 41, 51\nVMFINS BUILD 39\nVMFINS INSTALL 35, 38\nVMFINS INSTALL command 34\nVMFINS PRODLIST file 34\nVMFMRDSK 43\nVMFMRDSK command 46\nVMFPFPF command 48\nVMFREC 44\nVMFREC INFO command 45\nVMFREC PPF command 46\nVMFSETUP 44\nVMFSETUP command 45\nVMFVIEW BUILD command 49, 50\nVMFVIEW command 45, 46, 47\nVMFVIEW INSTALL 35, 39\nVMSES PARTCAT 42, 51\nVVT 47\nvolser 4\nVOLSER 4\nVSAM catalogs 70\nVTAM 69\nVTOC (volume table of contents) 61\n\nW\nwhat you receive\nservice 21, 43\nWindows\nhardware 83\nsoftware 83\nworksheet\ninstall, Windows 85\nplanning to install, Windows 83\nplanning to install, z/OS 3\nplanning to install, z/VM 27\nplanning to install, z/VSE 56\nwrite access software inventory disk 34\n\nZ\nz/OS publications 91\nz/VM publications 91\nz/VM System Delivery Option 28\nz/VSE\nplanning worksheet 55\npublications 59\nsystem requirements 57\nz/VSE publications 92\nReaders’ Comments — We’d Like to Hear from You\n\nHigh Level Assembler for z/OS & z/VM & z/VSE\nToolkit Feature\nInstallation and Customization Guide\nRelease 6\n\nPublication No. GC26-8711-08\n\nWe appreciate your comments about this publication. 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Note that other groups may also distribute\nworking documents as Internet-Drafts. The list of current Internet-\nDrafts is at https://datatracker.ietf.org/drafts/current/.\n\nInternet-Drafts are draft documents valid for a maximum of six months\nand may be updated, replaced, or obsoleted by other documents at any\ntime. It is inappropriate to use Internet-Drafts as reference\nmaterial or to cite them other than as \"work in progress.\"\n\nThis Internet-Draft will expire on 13 January 2022.\n\nCopyright Notice\n\nCopyright (c) 2021 IETF Trust and the persons identified as the\ndocument authors. All rights reserved.\n\nThis document is subject to BCP 78 and the IETF Trust’s Legal\nlicense-info) in effect on the date of publication of this document.\nPlease review these documents carefully, as they describe your rights\nand restrictions with respect to this document. Code Components\nextracted from this document must include Simplified BSD License text\nas described in Section 4.e of the Trust Legal Provisions and are\nprovided without warranty as described in the Simplified BSD License.\n1. Introduction\n\nThis document describes an RDAP extension for explicitly identifying redacted RDAP response fields, using JSONPath as the default expression language. A redacted RDAP field is one that has data removed from the RDAP response due to the lack of client privilege to receive the field. This extension can be used to identify redacted RDAP fields in any RDAP object class, as defined in [RFC7483], or RDAP fields defined in RDAP extensions. Because an RDAP response may exclude a field due to either the lack of data or based on the lack of RDAP client privileges, this extension is used to explicitly specify which RDAP fields are not included in the RDAP response due to redaction. It thereby provides a capability for disambiguation between redaction and possible other reasons for data or field absence.\n\nJSONPath, as defined in [I-D.ietf-jsonpath-base], is used as the default expression language to reference RDAP fields that have been redacted. The redacted JSON fields will either be removed or have empty values in the RDAP response. JSON is defined by [RFC8259].\n\n2. Conventions Used in This Document\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"NOT RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.\n3. Redaction Methods\n\nRedaction in RDAP can be handled in multiple ways. The use of placeholder text for the values of the RDAP fields, such as the placeholder text \"XXXX\", MUST NOT be used for redaction. A placeholder text value will not match the format requirements of each of the RDAP fields and provides an inconsistent and unreliable redaction signal. This section covers the redaction methods that can be used with the redaction signaling defined in Section 4.2.\n\nRDAP responses, as defined in [RFC7483], include a mix of JSON objects and JSON arrays, where JSON arrays are heavily used for entity objects with jCard [RFC7095]. jCard [RFC7095] is a JSON representation of vCard [RFC6350] that inherits its dependency on arrays. An example is the vCard [RFC6350] \"ADR\" property / jCard [RFC7095] \"adr\" property that defines a sequence of address components. According to [RFC6350], when an \"ADR\" property component value is missing, the associated component separator MUST still be specified. jCard [RFC7095] extends the use of arrays with each individual vCard property being represented by an array of three fixed elements, followed by one or more additional elements. The mix of JSON objects and JSON arrays impacts the methods used for redaction in RDAP. The redaction of RDAP fields fall into the two categories of Redaction by Removal Method (Section 3.1) and Redaction by Empty Value Method (Section 3.2), defined in the following subsections.\n\n3.1. Redaction by Removal Method\n\nThe Redaction by Removal Method is when the RDAP field is removed from the RDAP response, which is the preferred method. The Redaction by Removal Method can be done for all RDAP response fields other than the JSON arrays used with jCard [RFC7095]. When an RDAP object is redacted by removal, all of the RDAP object’s child fields are also removed. Only the redacted RDAP object needs to be referenced in the list of redacted fields, as defined in Section 4.2. An example of redacting an RDAP object is removing the administrative contact from the RDAP response and including the following \"redacted\" member:\n\"redacted\": [\n {\n \"name\": \"Administrative Contact\",\n \"path\": \"$\\cdot entities[?(@.roles[0]=='administrative')]$\",\n \"method\": \"removal\"\n \"reason\": \"Client request\"\n }\n]\n\nThe Redaction by Removal Method MUST NOT be used to remove a field from a jCard [RFC7095] fixed array position, which will result in a non-conformant jCard [RFC7095] array definition.\n\n3.2. Redaction by Empty Value Method\n\nThe Redaction by Empty Value Method is when a redacted field is not removed, but its value is set to an empty value, such as \"\" for a jCard [RFC7095] Text (\"text\") property or null for non-Text (\"text\") properties. The empty jCard [RFC7095] values (\"\" or null) are referenced in the \"redacted\" member in place of the jCard [RFC7095] property name, such as referencing the \"fn\" jCard property value at position 3 instead of referencing the \"fn\" jCard property name at position 0. The Redaction by Empty Value Method SHOULD be used only when redacting JSON response fields that use jCard [RFC7095] arrays. Optional jCard [RFC7095] properties SHOULD use the Redaction by Removal Method (Section 3.1) to redact the entire property. The required jCard [RFC7095] \"fn\" property, defined in section 6.2.1 of vCard [RFC6350], MUST use the Redaction by Empty Value Method to redact the property value. Removing the \"fn\" property would violate vCard [RFC6350] and removing the property value would violate the fixed array positions defined in jCard [RFC7095].\n\nAn example of the redacted field \"fn\" jCard property using the Redaction by Empty Value Method:\n\n```\n[ \n \"fn\", \n {}, \n \"text\", \n \"\"\n]\n```\n\nAn example of the \"redacted\" member for the redacted \"fn\" jCard property value, which is array position 3:\n\"redacted\": [\n{\n \"name\": \"Registrant Name\",\n \"path\": \"$.entities[?(@.roles[0]==’registrant’)].vcardArray[1][?(@[0]==’fn’)][3]\",\n \"pathLang\": \"jsonpPath\",\n \"method\": \"emptyValue\",\n \"reason\": \"Server policy\"\n}\n]\n\n4. Redacted RDAP Response\n\n4.1. RDAP Conformance\n\nRDAP responses that contain values described in this document MUST indicate conformance with this specification by including an rdapConformance ([RFC7483]) value of \"redacted_0\". The information needed to register this value in the RDAP Extensions Registry is described in Section 6.1.\n\nExample rdapConformance member with the redacted extension:\n\n\"rdapConformance\": [\n \"rdap_level_0\",\n \"redacted_0\"\n]\n\n4.2. \"redacted\" Member\n\nThe \"redacted\" member MUST be added to the RDAP response when there are redacted fields. The \"redacted\" member contains an array of redacted objects with the following child members:\n\n\"name\": A logical name for the redacted field. The logical name used for the redacted field is up to server policy. Conventions used for the chosen logical names MAY be defined in other documents to meet the needs of different RDAP services or industries.\n\n\"path\": The JSON expression of the redacted field, using the expression language defined by the \"pathLang\" member. The JSON expression references a removed JSON field or an empty field value based on Section 3.\n\n\"pathLang\": OPTIONAL JSON path expression language used, with the\ndefault value of \"jsonp-path\" for JSONPath ([I-D.ietf-jsonpath-base]). Other JSON path expression languages MAY be used based on server policy.\n\n\"method\": OPTIONAL redaction method used with \"removal\" indicating the Redaction By Removed Method (Section 3.1) and \"emptyValue\" indicating the Redaction by Empty Value Method (Section 3.2), with the default value of \"removal\".\n\n\"reason\": OPTIONAL human readable reason(s) for the redacted field in the language defined by the [RFC7483] \"lang\" member. The default language is \"en\" if the [RFC7483] \"lang\" member is not specified. The \"reason\" member is provided for informational purposes and MUST NOT be a client processing dependency.\n\nExample unredacted version of RDAP response:\n\n```javascript\n{\n \"rdapConformance\": [ \n \"rdap_level_0\"\n ],\n \"objectClassName\": \"domain\",\n \"handle\": \"ABC123\",\n \"ldhName\": \"example.com\",\n \"secureDNS\": {\n \"delegationSigned\": false\n },\n \"notices\": [ \n { \n \"title\": \"Terms of Use\",\n \"description\": [ \n \"Service subject to Terms of Use.\"\n ],\n \"links\": [ \n { \n \"rel\": \"self\",\n \"href\": \"https://www.example.com/terms-of-use\",\n \"type\": \"text/html\",\n \"value\": \"https://www.example.com/terms-of-use\"\n }\n ]\n }\n ],\n \"nameservers\": [ \n { \n \"objectClassName\": \"nameserver\",\n \"ldhName\": \"ns1.example.com\"\n }\n ],\n}\n```\n\n{ \"objectClassName\": \"nameserver\", \"ldhName\": \"ns2.example.com\" },\n\"entities\": [\n { \"objectClassName\": \"entity\", \"handle\": \"123\", \"roles\": [ \"registrar\" ], \"publicIds\": [ { \"type\": \"IANA Registrar ID\", \"identifier\": \"1\" } ], \"vcardArray\": [ \"vcard\", [ [ \"version\", {}, \"text\", \"4.0\"\n ], [ \"fn\", {}, \"text\", \"Example Registrar Inc.\" ], [ \"adr\", {}, \"text\", [ \"\", \"Suite 100\", \"123 Example Dr.\", \"Dulles\", \"VA\", \"20166-6503\", \"US\" ] ]\n ]\n ]\n]\n\"email\",\n{},\n\"text\",\n\"contact@organization.example\"\n],\n[\n\"tel\",\n{\n\"type\": \"voice\"\n},\n\"uri\",\n\"tel:+1.7035555555;ext=1234\"\n],\n[\n\"tel\",\n{\n\"type\": \"fax\"\n},\n\"uri\",\n\"tel:+1.7035555556\"\n]\n],\n\"entities\": [\n{\n\"objectClassName\": \"entity\",\n\"roles\": [\n\"abuse\"\n],\n\"vcardArray\": [\n\"vcard\",\n[\n[\"version\",\n{},\n\"text\",\n\"4.0\"\n],\n[\"fn\",\n{},\n\"text\",\n\"Abuse Contact\"\n],\n[\"email\",\n{},\n\"text\",\n\"contact@organization.example\"\n],\n[\"uri\",\n\"tel:+1.7035555555;ext=1234\"\n],\n[\"uri\",\n\"tel:+1.7035555556\"\n]\n],\n\"entities\": [\n\n\"abuse@organization.example\",\n],\n[\n\"tel\",\n{\n\"type\": \"voice\"\n},\n\"uri\",\n\"tel:+1.7035555555;ext=1234\"\n}\n]\n]\n],\n{\n\"roles\": [\n\"registrant\"\n],\n\"vcardArray\": [\n\"vcard\",\n[\n[ \"version\",\n{},\n\"text\",\n\"4.0\"\n],\n[ \"fn\",\n{},\n\"text\",\n\"Registrant User\"\n],\n[ \"org\",\n{},\n\"text\",\n\"Example Inc.\"\n],\n[ \"adr\",\n{},\n\"text\",\n[ \"Suite 1235\",\n\"4321 Rue Somewhere\",\n]\n\"Quebec\",\n\"QC\",\n\"G1V 2M2\",\n\"Canada\"\n],\n[\n \"email\",\n {\n \"text\",\n \"registrant.user@example.com\"\n }\n],\n[\n \"tel\",\n {\n \"type\": \"voice\"\n },\n \"uri\",\n \"tel:+1-555-555-1235;ext=123\"\n],\n[\n \"tel\",\n {\n \"type\": \"fax\"\n },\n \"uri\",\n \"tel:+1-555-555-5321\"\n]\n],\n\",\n{\n \"roles\": [\n \"technical\"\n ],\n \"vcardArray\": [\n \"vcard\",\n [\n \"version\",\n {}\n ],\n \"text\",\n \"4.0\"\n ],\n [\n \"fn\",\n {}\n ],\n \"text\",\n \"registrant.user@example.com\"}\n\"Technical User\",\n]\n]\n\"org\",\n{}\n\"text\",\n\"Example Inc.\"\n],\n\"adr\",\n{}\n\"text\",\n[ \"Suite 1234\",\n\"4321 Rue Somewhere\",\n\"Quebec\",\n\"QC\",\n\"G1V 2M2\",\n\"Canada\"\n],\n\"email\",\n{}\n\"text\",\n\"technical.user@example.com\"\n],\n\"tel\",\n{\n\"type\": \"voice\"\n},\n\"uri\",\n\"tel:+1-555-555-1234;ext=321\"\n],\n\"tel\",\n{\n\"type\": \"fax\"\n},\n\"uri\",\n\"tel:+1-555-555-4321\"\n\"roles\": [\n \"administrative\"\n],\n\"vcardArray\": [\n \"vcard\",\n [\n \"version\",\n {},\n \"text\",\n \"4.0\"\n ],\n \"fn\",\n {},\n \"text\",\n \"Administrative User\"\n],\n \"org\",\n {},\n \"text\",\n \"Example Inc.\"\n],\n \"adr\",\n {},\n \"text\",\n [\n \"Suite 1236\",\n \"4321 Rue Somewhere\",\n \"Quebec\",\n \"QC\",\n \"G1V 2M2\",\n \"Canada\"\n ],\n \"email\",\n {},\n \"text\",\n \"administrative.user@example.com\"\n],\n \"tel\",\n {\n \"type\": \"voice\"\nExample redacted version of RDAP response:\n\n```json\n{\n \"rdapConformance\": [\n \"rdap_level_0\",\n \"redacted_0\"\n ],\n \"objectClassName\": \"domain\",\n \"ldhName\": \"example.com\",\n \"secureDNS\": {\n \"uri\",\n \"tel:+1-555-555-1236;ext=789\"\n },\n \"events\": [\n { \"eventAction\": \"registration\", \"eventDate\": \"1997-06-03T00:00:00Z\" },\n { \"eventAction\": \"last changed\", \"eventDate\": \"2020-05-28T01:35:00Z\" },\n { \"eventAction\": \"expiration\", \"eventDate\": \"2021-06-03T04:00:00Z\" }\n ],\n \"status\": [\n \"server delete prohibited\",\n \"server update prohibited\",\n \"server transfer prohibited\",\n \"client transfer prohibited\"\n ]\n}\n```\n\"delegationSigned\": false,\n\"notices\": [\n {\n \"title\": \"Terms of Use\",\n \"description\": [\n \"Service subject to Terms of Use.\"\n ],\n \"links\": [\n {\n \"rel\": \"self\",\n \"href\": \"https://www.example.com/terms-of-use\",\n \"type\": \"text/html\",\n \"value\": \"https://www.example.com/terms-of-use\"\n }\n ]\n }\n],\n\"nameservers\": [\n {\n \"objectClassName\": \"nameserver\",\n \"ldhName\": \"ns1.example.com\"\n },\n {\n \"objectClassName\": \"nameserver\",\n \"ldhName\": \"ns2.example.com\"\n }\n],\n\"entities\": [\n {\n \"objectClassName\": \"entity\",\n \"handle\": \"123\",\n \"roles\": [\n \"registrar\"\n ],\n \"publicIds\": [\n {\n \"type\": \"IANA Registrar ID\",\n \"identifier\": \"1\"\n }\n ],\n \"vcardArray\": [\n \"vcard\",\n [\n {\n \"version\":\n },\n \"text\",\n ]\n ]\n }\n]\n\"4.0\"\n],\n[ \"fn\",\n {}\n],\n\"text\",\n\"Example Registrar Inc.\"\n],\n[ \"adr\",\n {}\n],\n\"text\",\n[ \"\"\n, \"Suite 100\",\n \"123 Example Dr.\",\n \"Dulles\",\n \"VA\",\n \"20166-6503\",\n \"US\"\n]\n],\n[ \"email\",\n {}\n],\n\"text\",\n\"contact@organization.example\"\n],\n[ \"tel\",\n {\n \"type\": \"voice\"\n },\n \"uri\",\n \"tel:+1.7035555555\"\n],\n[ \"tel\",\n {\n \"type\": \"fax\"\n },\n \"uri\",\n \"tel:+1.7035555556\"\n]\n],\n\"entities\": [ }\n}\n}\n\"objectClassName\": \"entity\",\n\"roles\": [\n \"abuse\"\n],\n\"vcardArray\": [\n \"vcard\",\n [\n [\n \"version\",\n {},\n \"text\",\n \"4.0\"\n ],\n [\n \"fn\",\n {},\n \"text\",\n \"Abuse Contact\"\n ],\n [\n \"email\",\n {},\n \"text\",\n \"abuse@organization.example\"\n ],\n [\n \"tel\",\n {\n \"type\": \"voice\"\n },\n \"uri\",\n \"tel:+1.7035555555\"\n ]\n ]\n],\n\"roles\": [\n \"registrant\"\n],\n\"vcardArray\": [\n \"vcard\",\n [\n [\n \"version\",\n {},\n \"text\",\n \"4.0\"\n ],\n [\n \"fn\",\n {},\n \"text\",\n \"Abuse Contact\"\n ],\n [\n \"email\",\n {},\n \"text\",\n \"abuse@organization.example\"\n ],\n [\n \"tel\",\n {\n \"type\": \"voice\"\n },\n \"uri\",\n \"tel:+1.7035555555\"\n ]\n ]\n]\n\"text\",\n\"4.0\"\n],\n[ \"fn\",\n{},\n\"text\",\n\"\n],\n[ \"adr\",\n{},\n\"text\",\n[ \"\", \",\",\n\"\", \",\",\n\"\", \",\",\n\"QC\",\n\",\",\n\"Canada\"\n] ]\n] ]\n},\n{ \"roles\": [\n \"technical\"\n],\n\"vcardArray\": [\n \"vcard\",\n [ [ \"version\",\n {},\n \"text\",\n \"4.0\"\n ],\n [ \"fn\",\n {},\n \"text\",\n \"\"\n ],\n [ \"org\",\n {},\n \"\"\n ]]\n]}\n}\n]\n\"text\",\n \"Example Inc.\"\n],\n[ \n \"adr\",\n {},\n \"text\",\n [ \n \"\",\n \"Suite 1234\",\n \"4321 Rue Somewhere\",\n \"Quebec\",\n \"QC\",\n \"G1V 2M2\",\n \"Canada\"\n ]\n]\n],\n\"events\": [\n {\n \"eventAction\": \"registration\",\n \"eventDate\": \"1997-06-03T00:00:00Z\"\n },\n {\n \"eventAction\": \"last changed\",\n \"eventDate\": \"2020-05-28T01:35:00Z\"\n },\n {\n \"eventAction\": \"expiration\",\n \"eventDate\": \"2021-06-03T04:00:00Z\"\n }\n],\n\"status\": [\n \"server delete prohibited\",\n \"server update prohibited\",\n \"server transfer prohibited\",\n \"client transfer prohibited\"\n],\n\"redacted\": [\n {\n \"name\": \"Registry Domain ID\",\n \"path\": \".handle\",\n \"pathLang\": \"jsonpath\",\n \"method\": \"removal\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Registrant Name\",\n \"path\": \"$.entities[?(@.roles[0]==‘registrant’)].vcardArray[1][?(@[0]==‘fn’)][3]\",\n \"pathLang\": \"jsonpath\",\n \"method\": \"emptyValue\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Registrant Organization\",\n \"path\": \"$.entities[?(@.roles[0]==‘registrant’)].vcardArray[1][?(@[0]==‘org’)]\",\n \"pathLang\": \"jsonpath\",\n \"method\": \"removal\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Registrant Street\",\n \"path\": \"$.entities[?(@.roles[0]==‘registrant’)].vcardArray[1][?(@[0]==‘adr’)][3][3]\",\n \"pathLang\": \"jsonpath\",\n \"method\": \"emptyValue\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Registrant City\",\n \"path\": \"$.entities[?(@.roles[0]==‘registrant’)].vcardArray[1][?(@[0]==‘adr’)][3][3]\",\n \"pathLang\": \"jsonpath\",\n \"method\": \"emptyValue\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Registrant Postal Code\",\n \"path\": \"$.entities[?(@.roles[0]==‘registrant’)].vcardArray[1][?(@[0]==‘adr’)][3][5]\",\n \"pathLang\": \"jsonpath\",\n \"method\": \"emptyValue\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Registrant Email\",\n \"path\": \"$.entities[?(@.roles[0]==‘registrant’)].vcardArray[1][?(@[0]==‘email’)]\",\n \"method\": \"removal\",\n \"reason\": \"Server policy\"\n}\n{\n \"name\": \"Registrant Phone\",\n \"path\": \"$.entities[?(@.roles[0]==‘registrant’)].vcardArray[1][?(@[1].type==’voice’)]\",\n \"method\": \"removal\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Technical Name\",\n \"path\": \"$.entities[?(@.roles[0]==‘technical’)].vcardArray[1][?(@[0]==‘fn’)][3]\",\n \"method\": \"emptyValue\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Technical Email\",\n \"path\": \"$.entities[?(@.roles[0]==‘technical’)].vcardArray[1][?(@[0]==‘email’)]\",\n \"method\": \"removal\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Technical Phone\",\n \"path\": \"$.entities[?(@.roles[0]==‘technical’)].vcardArray[1][?(@[1].type==’voice’)]\",\n \"method\": \"removal\",\n \"reason\": \"Server policy\"\n},\n{\n \"name\": \"Technical Fax\",\n \"path\": \"$.entities[?(@.roles[0]==‘technical’)].vcardArray[1][?(@[1].type==’fax’)]\",\n \"reason\": \"Client request\"\n},\n{\n \"name\": \"Administrative Contact\",\n \"path\": \"$.entities[?(@.roles[0]==‘administrative’)]\",\n \"method\": \"removal\",\n \"reason\": \"Client request\"\n}\n}\n5. JSONPath Considerations\n\nJSONPath [I-D.ietf-jsonpath-base] is the default JSON path expression language. This section covers considerations for servers using [I-D.ietf-jsonpath-base] to identify redacted RDAP fields with the \"path\" member of redacted objects in the \"redacted\" member. The list of JSONPath considerations include:\n\n1. Use absolute paths with the ‘$’ JSONPath element. An example is \"$.handle\" for the \"Registry Domain ID\".\n2. Validate a JSONPath expression using a non-redacted RDAP response, where evaluating the expression results in returning the redacted field.\n3. Reference the removed object field when redacting an entire object by the Redaction by Removal Method (Section 3.1), where all of the object’s child fields are explicitly removed. An example is \"$.entities[?(@.roles[0]==’administrative’)]]\" for the entire \"Administrative Contact\".\n4. Reference the removed field when using the Redaction by Removal Method (Section 3.1). An example is \"$.handle\" for the \"Registry Domain ID\".\n5. Reference index 0 of the jCard [RFC7095] property array, which is the jCard [RFC7095] \"name\" property, with a filter expression containing the name of the field, when redacting a jCard [RFC7095] field using the Redaction by Removal Method (Section 3.1). An example is \"$.entities[?(@.roles[0]==’registrant’)].vcardArray[1][?(@[0]==’email’)]\" for the \"Registrant Email\".\n6. Reference jCard [RFC7095] field value or values redacted by array index 3 and greater, when redacting a jCard [RFC7095] field using the Redaction by Empty Value Method (Section 3.2). The jCard [RFC7095] property array index 3 and greater contain the property values, where the property values set with an empty value are referenced directly in place of the jCard [RFC7095] property name. Servers can then systematically redact jCard [RFC7095] field value or values based on the JSONPath expressions and clients will directly know which jCard [RFC7095] property values have been redacted. An example is \"$.entities[?(@.roles[0]==’registrant’)].vcardArray[1][?(@[0]==’fn’)][3]\" for the \"Registrant Name\" or \"$.entities[?(@.roles[0]==’registrant’)].vcardArray[1][?(@[0]==’adr’)][3][5]\" for the \"Registrant Postal Code\".\n\n6. IANA Considerations\n\n6.1. RDAP Extensions Registry\n\nIANA is requested to register the following value in the RDAP Extensions Registry:\n\nExtension identifier: redacted_0\nRegistry operator: Any\nPublished specification: This document.\nContact: IESG <iesg@ietf.org>\nIntended usage: This extension identifies the redacted fields in an RDAP response.\n\n7. Security Considerations\n\nThe server including a redacted signal provides an unauthorized client additional information related to the existence of data. Servers MAY exclude the redacted members for RDAP fields that are considered a privacy issue in providing a data existence signal.\n\n8. Acknowledgements\n\nThe authors wish to thank the following persons for their feedback and suggestions: Scott Hollenbeck, and Rick Wilhelm.\n\n9. References\n\n9.1. Normative References\n\n[I-D.ietf-jsonpath-base]\nNormington, G., Surov, E., Mikulicic, M., and F. Dortmund, \"JavaScript Object Notation (JSON) Path\", Work in Progress, Internet-Draft, draft-ietf-jsonpath-base-00, 7 March 2021,\n\n[RFC2119] Bradner, S., \"Key words for use in RFCs to Indicate Requirement Levels\", BCP 14, RFC 2119,\nDOI 10.17487/RFC2119, March 1997,\n\n[RFC6350] Perreault, S., \"vCard Format Specification\", RFC 6350,\nDOI 10.17487/RFC6350, August 2011,\n\nDOI 10.17487/RFC7095, January 2014,\n<https://www.rfc-editor.org/info/rfc7095>.\n\n[RFC7483] Newton, A. and S. Hollenbeck, \"JSON Responses for the Registration Data Access Protocol (RDAP)\", RFC 7483,\nDOI 10.17487/RFC7483, March 2015,\n\n\nAuthors’ Addresses\n\nJames Gould\nVeriSign, Inc.\n12061 Bluemont Way\nReston, VA 20190\nUnited States of America\n\nEmail: jgould@verisign.com\nURI: http://www.verisigninc.com\n\nDavid Smith\nVeriSign, Inc.\n12061 Bluemont Way\nReston, VA 20190\nUnited States of America\n\nEmail: dsmith@verisign.com\nURI: http://www.verisigninc.com\n\nJody Kolker\nGoDaddy Inc.\n14455 N. Hayden Rd. #219\nScottsdale, AZ 85260\nUnited States of America\n\nEmail: jkolker@godaddy.com\nURI: http://www.godaddy.com\n\nRoger Carney\nGoDaddy Inc.\n14455 N. Hayden Rd. #219\nScottsdale, AZ 85260\nUnited States of America\n\nEmail: rcarney@godaddy.com\nURI: http://www.godaddy.com\nAbstract\n\nMultiple applications related to the registration of names and other identifiers are built around a list of data elements. There is currently no unified public list of these data elements, nor is there an organized and independent change control process. This document codifies the multiple similar but not quite identical lists of data elements into a neutral Data Dictionary to be maintained as an independent IANA Registry. The Data Dictionary defines data elements but does not specify which ones are to be used in any particular application; the Data Dictionary is policy-neutral.\n\nStatus of This Memo\n\nThis Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.\n\nInternet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.\n\nInternet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as \"work in progress.\"\n\nThis Internet-Draft will expire on 8 September 2022.\n\nCopyright Notice\n\nCopyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved.\n\nThis document is subject to BCP 78 and the IETF Trust’s Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components\nTable of Contents\n\n1. Introduction ................................................. 3\n 1.1. Requirements Language .............................. 3\n\n2. Data Element Specification ................................. 4\n 2.1. Element name: Domain Name .......................... 4\n 2.2. Element name: Registry ............................... 4\n 2.3. Element name: NS ..................................... 4\n 2.4. Element name: Registration Creation Date .......... 5\n 2.5. Element name: Registration Expiration Date ........ 5\n 2.6. Element name: Registration Updated Date .......... 5\n 2.7. Element name: Registration Transfer Date .......... 5\n 2.8. Element name: Protection ............................. 5\n 2.9. Element name: Nexus .................................. 5\n 2.10. Element name: Person ................................ 5\n 2.11. Element name: Personal ............................... 5\n 2.12. Element name: Status & Locks ....................... 5\n 2.13. Element name: Source & Method ..................... 6\n 2.14. Element name: Payment History ...................... 6\n 2.15. Element name: Transaction History ................. 6\n 2.16. Element name: User Account ID ...................... 6\n 2.17. Element name: Reserved .............................. 6\n 2.18. Element name: Name ................................ 6\n 2.19. Element name: Org .................................. 6\n 2.20. Element name: Street ................................ 6\n 2.21. Element name: City ................................ 6\n 2.22. Element name: State/Province ....................... 7\n 2.23. Element name: Postal code ......................... 7\n 2.24. Element name: Country ............................... 7\n 2.25. Element name: Phone ................................ 7\n 2.26. Element name: Phone ext ............................ 7\n 2.27. Element name: Fax ................................ 7\n 2.28. Element name: Fax ext .............................. 7\n 2.29. Element name: Email ................................. 8\n 2.30. Element name: Email_or_phone ...................... 8\n 2.31. Element name: Registry UniqueID ................. 8\n\n3. IANA Considerations ......................................... 8\n 3.1. Report Specification ................................. 8\n 3.1.1. Designated Expert Evaluation Criteria ........... 8\n 3.1.2. Registration Procedure .......................... 9\n 3.2. Initial assignments .................................. 11\n 3.2.1. Data Element Definition in IANA Registry ........ 11\n\n4. Security Considerations .................................... 12\n\n5. Privacy Considerations ..................................... 12\n1. Introduction\n\nThe DNS Data Dictionary provides a common set of names and definitions for data elements which may be used in a DNS related protocol. The dictionary is intended to be inclusive and not obligatory. That is, the existence of a data element in this dictionary does not imply the data element must be used or recognized in any particular protocol. The items in this dictionary should represent the union for what is in existing relevant protocols, and should prevent divergence in new protocols. We also expect that each application or protocol may have additional requirements specific to the application or protocol. Such additional requirements should be documented as part of the application or protocol specification.\n\nThe data dictionary currently has thirty-one data elements. These data elements include the DNS records, the detailed status of a registration to the details for each of the contacts, and the account details and payment history. The proposed IANA registry lists standard data elements and their syntax for inclusion in the files.\n\nWe expect the DNS data dictionary to evolve to meet the needs of various applications. With the exception of correction of errors, we expect the changes to the DNS Data Dictionary to be additions as opposed to deletions or changes.\n\n[Comment: We are looking for additional authors and contributors to add to and improve the data dictionary, keeping in line with the RFC Series Editor statement on authorship. https://www.rfc-editor.org/pipermail/rfc-interest/2015-May/008869.html]\n\n1.1. Requirements Language\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"NOT RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.\n2. Data Element Specification\n\nEach data element is a single unit of information that can be collected and compared during the registration process. The primary purposes of the IANA registry of data elements are to ensure that each data element is assigned a unique name and that the syntax of each data element is specified.\n\nEach data element is assigned to an element type to organize the taxonomy of the data dictionary.\n\nThe name of the data element MUST be unique and this characteristic MUST be enforced by the registry. The character encoding recommendation for data elements is specified in Section 3.\n\nThe subsections below comprise an initial list of known data elements commonly being used in the templates. The title of the subsection is the data element name for the data element. The combination of data element type and data element name MUST be unique and MUST be processed as case insensitive in the IANA registry.\n\nNote that the legal definition of any of the terms used in the data dictionary, such as 'personally identifiable information' or 'legal person', are to be determined locally. The organization using this dictionary will record their interpretation in the appropriate element.\n\n2.1. Element name: Domain Name\n\nThis is the domain name as formatted according to the Internationalized Domain Names for Applications (IDNA) specification.[RFC5890]\n\nSee also \"Domain name\" in [RFC8499].\n\n2.2. Element name: Registry\n\nThe name of the registry. This data element is text/string with no naming convention enforced.\n\nSee also \"Registry\" in [RFC8499].\n\n2.3. Element name: NS\n\nThe authoritative name server for the domain.[RFC1034]\n\nSee also \"Authoritative server\" in [RFC8499]\n2.4. Element name: Registration Creation Date\n\nThe date and time of domain object creation. Format TBD.\n\n2.5. Element name: Registration Expiration Date\n\nThe date and time identifying the end of the domain object’s registration period. Format TBD.\n\n2.6. Element name: Registration Updated Date\n\nThe date and time of the most recent domain-object modification. Format TBD.\n\n2.7. Element name: Registration Transfer Date\n\nThe date and time of the most recent successful domain-object transfer. Format TBD.\n\n2.8. Element name: Protection\n\nDefinition is TBD.\n\n2.9. Element name: Nexus\n\nDefinition is TBD.\n\n2.10. Element name: Person\n\nDefinition is TBD.\n\n2.11. Element name: Personal\n\nDefinition is TBD.\n\n2.12. Element name: Status & Locks\n\nExamples include the EPP (Section 2.3 of [RFC5731]) and RDAP (Section 10.2.2 of [RFC9083]) codes (ex: clientTransferProhibited) that describe the current state of a registered domain name and the protocol actions that can (or cannot) be performed on the domain name. A registered domain name MAY be associated with multiple status values. Other managed objects, including name server and contact objects, can also have status and lock values.\n2.13. Element name: Source & Method\n\nDefinition is TBD.\n\n2.14. Element name: Payment History\n\nDefinition is TBD.\n\n2.15. Element name: Transaction History\n\nDefinition is TBD.\n\n2.16. Element name: User Account ID\n\nDefinition is TBD.\n\n2.17. Element name: Reserved\n\n[this field is an artifact of prior use which was determined to not be necessary, but the field was left intact for future use]\n\n2.18. Element name: Name\n\nIndividual name is represented using character strings. These strings have a specified minimum length and a specified maximum length. Individual names MAY be provided in either UTF-8 [RFC3629] or a subset of UTF-8 that can be represented in 7-bit ASCII, depending on local needs.\n\n2.19. Element name: Org\n\nOrganization name is represented using character strings. These strings have a specified minimum length and a specified maximum length. Organizational names MAY be provided in either UTF-8 [RFC3629] or a subset of UTF-8 that can be represented in 7-bit ASCII, depending on local needs.\n\n2.20. Element name: Street\n\nPostal street address, formatted as per [ISO19160-4].\n\n2.21. Element name: City\n\nPostal city address, formatted as per [ISO19160-4].\n2.22. Element name: State/Province\n\nPostal state or province address, formatted as per [ISO19160-4].\n\n2.23. Element name: Postal code\n\nPostal code, formatted as per [ISO19160-4]. Contact postal codes are represented using character strings. These strings have a specified minimum length and a specified maximum length.\n\n2.24. Element name: Country\n\nCountry code identifier. Contact country identifiers are represented using two-character identifiers specified in [ISO3166-1].\n\n2.25. Element name: Phone\n\nTelephone number structure is derived from structures defined in [ITU.E164.2005]. Telephone numbers described in this mapping are character strings that MUST begin with a plus sign (\"+\", ASCII value 0x002B), followed by a country code defined in [ITU.E164.2005], followed by a dot (\".\", ASCII value 0x002E), followed by a sequence of digits representing the telephone number. An optional \"x\" attribute is provided to note telephone extension information.\n\n2.26. Element name: Phone ext\n\nThis field is intended to represent an \"extension\" within the phone number to reach the specific person or role desk telephone, appropriate queue or mailbox after successfully dialing the Phone element.\n\n2.27. Element name: Fax\n\nFax telephone number structure is derived from structures defined in [ITU.E164.2005]. Telephone numbers described in this mapping are character strings that MUST begin with a plus sign (\"+\", ASCII value 0x002B), followed by a country code defined in [ITU.E164.2005], followed by a dot (\".\", ASCII value 0x002E), followed by a sequence of digits representing the telephone number.\n\n2.28. Element name: Fax ext\n\nThis field is an \"extension\" within a phone tree or PBX that is necessary to connect to a fax machine after successfully dialing the fax element.\n2.29. Element name: Email\n\n Email address syntax is defined in [RFC5322].\n\n2.30. Element name: Email_or_phone\n\n There is a requirement that either the phone or email element have\n been confirmed reachable, which this field is intended to represent.\n\n2.31. Element name: Registry UniqueID\n\n This field represents server-unique identifiers assigned to entities,\n such as clients and contacts. These identifiers are character\n strings that typically have a specified minimum length, a specified\n maximum length, and a specified format.\n\n3. IANA Considerations\n\n This section describes the format of the IANA Registration Report\n Registry, which has two tables described below, and the procedures\n used to populate and manage the registry entries.\n\n3.1. Report Specification\n\n This registry uses the \"Specification Required\" policy described in\n [RFC8126]. An English language version of the extension\n specification is required in the registry, though non-English\n versions of the specification may also be provided.\n\n The \"Specification Required\" policy implies review by a \"designated\n expert\". Section 5.2 of RFC 8126 describes the role of designated\n experts and the function they perform.\n\n3.1.1. Designated Expert Evaluation Criteria\n\n A high-level description of the role of the designated expert is\n described in Section 5.2 of RFC 8126. Specific guidelines for the\n appointment of designated experts and the evaluation of a new data\n element is provided here.\nThe IESG SHOULD appoint a small pool of individuals (perhaps 3 - 5) to serve as designated experts, as described in Section 5.2 of RFC 8126. The pool should have a single administrative chair who is appointed by the IESG. The designated experts should use the existing regext mailing list (regext@ietf.org) for public discussion of registration requests. This implies that the mailing list should remain open after the work of the REGEXT working group has concluded.\n\nThe results of the evaluation should be shared via email with the registrant and the regext mailing list. Issues discovered during the evaluation can be corrected by the registrant, and those corrections can be submitted to the designated experts until the designated experts explicitly decide to accept or reject the registration request. The designated experts must make an explicit decision and that decision must be shared via email with the registrant and the regext mailing list. If the specification for a data element or report is an IETF Standards Track document, no review is required by the designated expert.\n\nDesignated experts should be permissive in their evaluation of requests for data elements and reports that have been implemented and deployed by at least one registry. This implies that it may indeed be possible to register multiple data elements or reports that provide the same functionality. Requests to register data elements or reports that have not been deployed should be evaluated with a goal of reducing duplication. A potential registrant who submits a request to register a new data element or report that includes similar functionality to existing data elements or reports should be made aware of the existing data elements and reports. The registrant should be asked to reconsider their request given the existence of similar data elements or reports. Should they decline to do so, perceived similarity should not be a sufficient reason for rejection as long as all other requirements are met.\n\n3.1.2. Registration Procedure\n\nThe registry contains information describing each registered data element or report. Registry entries are created and managed by sending forms to IANA that describe the data element or report for the registry entry.\n\n3.1.2.1. Required Information\n\nThe required information must be formatted consistently using the following registration form. Form field names and values may appear on the same line.\n3.1.2.1.1. Data Element Definition\n\nName of data element type\n\nMUST be unique within the registry, enforced to be unique, and MUST be processed as case insensitive\n\nName of data element\n\nMUST be unique within the registry, enforced to be unique, and MUST be processed as case insensitive\n\nReference document\n\nMUST define the data element, SHOULD be a URL to a RFC, and SHOULD include the section number (or other detailed internal document reference), MAY be a URL to any document available under equivalent terms\n\nRegistrant\n\nWill be IESG for initial entries and all Standards Track specifications; otherwise as specified by the registrant\n\nStatus\n\nMUST be one of active, inactive, or unknown\n\n3.1.2.2. Registration Processing\n\nRegistrants should send each registration form to IANA with a single record for incorporation into the registry. Send the form via email to iana@iana.org or complete the online form found on the IANA website. The subject line should indicate whether the enclosed form represents an insertion of a new record (indicated by the word \"INSERT\" in the subject line) or a replacement of an existing record (indicated by the word \"MODIFY\" in the subject line). At no time can a record be deleted from the registry. On receipt of the registration request, IANA will initiate review by the designated expert(s) if appropriate, who will evaluate the request using the criteria in Section 3.1.1 in consultation with the regext mailing list.\n3.1.2.3. Updating Report Definition Registry Entries\n\nWhen submitting changes to existing registry entries, include text in the \"Notes\" field of the registration form describing the change. Under normal circumstances, registry entries are only to be updated by the registrant. If the registrant becomes unavailable or otherwise unresponsive, the designated expert can submit a registration form to IANA to update the registrant information. Entries can change state from \"Active\" to \"Inactive\" and back again as long as state-change requests conform to the processing requirements identified in this document. In addition to entries that become \"Inactive\" due to a lack of implementation, entries for which a specification becomes consistently unavailable over time should be marked \"Inactive\" by the designated expert until the specification again becomes reliably available.\n\n3.2. Initial assignments\n\n3.2.1. Data Element Definition in IANA Registry\n\n--- BEGIN FORM ---\n\nName of data element:\nDomain Name\nReference:\nThis RFC Section 2.1.\nRegistrant:\nIESG, iesg@ietf.org\nStatus:\nActive\n--- END FORM ---\n--- BEGIN FORM ---\nName of data element:\n............\nReference:\n4. Security Considerations\n\nThis specification does not consider the issues of distribution or access to the reports that are created and thus does not introduce any new security concerns that are not already present in the local environment in which the report is created.\n\nA security principle to keep in mind as new reports are developed is that it is considered a bad practice to report or disclose security information. In the case of the registration system upon which this reporting mechanism is based, the authInfo code is a specific example of a data element that SHOULD NOT be included in a report.\n\n5. Privacy Considerations\n\nThis specification defines a mechanism for policy comparison based on data in a registration system. Some of that data is likely to be considered personally identifiable information (PII) and thus would be subject to privacy protection according to an applicable privacy regulation. It is outside the scope of this specification to address those specific concerns. Implementors are urged to consider these issues with their local legal authority and develop appropriate requirements for their work.\n\n6. Internationalization Considerations\n\nThe character encoding for the file contents MUST use UTF-8. Throughout this document A-LABEL is indicated as a SHOULD and that MUST be interpreted as follows. All domain name labels MUST be in A-LABEL format if it is possible to represent it as an A-LABEL, otherwise U-LABEL MAY be used.\n\n7. Draft Change Log\n\n-01: Updated abstract to clarify that this draft does not intend to set policy.\n-01: Updated definitions in 2.1, 2.4, 2.5, 2.6, 2.7 to remove normative reference to the EPP spec.\n\n-01: Updated 2. Data Element specification to note local interpretation expected for any legal definitions.\n\n-01: Added TBD to policy-related items, all data-related elements wrt format.\n\n-01: Moved several items from informative to normative references.\n\n8. Acknowledgements\n\nWith many thanks to James Galvin and Rod Rasmussen for their advice and feedback on this data dictionary.\n\n9. References\n\n9.1. Informative References\n\n\n9.2. Normative References\n\n\n[ITU.E164.2005]\n\n\nAuthors’ Addresses\n\nHeather Flanagan (editor)\nEdgemoor Research Institute\nEmail: hlf@sphericalcowconsulting.com\n\nSteve Crocker\nEdgemoor Research Institute\nEmail: steve@shinkuro.com\nUse of Internationalized Email Addresses in the Extensible Provisioning Protocol (EPP)\ndraft-ietf-regext-epp-eai-08\n\nAbstract\n\nThis document describes an EPP extension that permits usage of Internationalized Email Addresses in the EPP protocol and specifies the terms when it can be used by EPP clients and servers. The Extensible Provisioning Protocol (EPP), being developed before appearing the standards for Internationalized Email Addresses (EAI), does not support such email addresses.\n\nTO BE REMOVED on turning to RFC: The document is edited in the dedicated github repo (https://github.com/beldmit/eppeai). Please send your submissions via GitHub.\n\nStatus of This Memo\n\nThis Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.\n\nInternet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.\n\nInternet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as \"work in progress.\"\n\nThis Internet-Draft will expire on 5 October 2022.\n\nCopyright Notice\n\nCopyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved.\nThis document is subject to BCP 78 and the IETF Trust’s Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.\n\nTable of Contents\n\n1. Introduction ............................................. 3\n 1.1. Conventions Used in This Document .................. 3\n2. Migrating to Newer Versions of This Extension .............. 3\n3. Email Address Specification .............................. 4\n4. Functional Extension .................................... 4\n5. Internationalized Email Addresses (EAI) Functional Extension ............................................. 5\n 5.1. Scope of Functional Extension ........................ 5\n 5.2. Signaling Client and Server Support ................. 5\n 5.3. Functional Extension Behavior ....................... 5\n 5.3.1. EAI Functional Extension Negotiated ............. 5\n 5.3.2. EAI Functional Extension Not Negotiated ......... 6\n6. IANA Considerations ..................................... 7\n 6.1. XML Namespace ........................................ 7\n 6.2. EPP Extension Registry .............................. 7\n7. Implementation Status ..................................... 8\n 7.1. Verisign EPP SDK ................................... 8\n8. Security Considerations .................................. 9\n9. Acknowledgments ......................................... 9\n10. References ................................................ 9\n 10.1. Normative References ............................... 9\n 10.2. Informative References ............................. 10\nAppendix A. Change History .................................. 10\n A.1. Change from 00 to 01 ................................ 11\n A.2. Change from 01 to 02 ................................ 11\n A.3. Change from 02 to 03 ................................ 11\n A.4. Change from 03 to 04 ................................ 11\n A.5. Change from 04 to the regext 01 version ............. 11\n A.6. Change from the regext 01 to regext 02 version ...... 11\n A.7. Change from the regext 02 to regext 03 version ...... 11\n A.8. Change from the regext 03 to regext 04 version ...... 12\n A.9. Change from the regext 04 to regext 05 version ...... 12\n A.10. Change from the regext 05 to regext 06 version ...... 12\n A.11. Change from the regext 06 to regext 07 version ...... 12\n A.12. Change from the regext 07 to regext 08 version ...... 12\nAuthors’ Addresses .......................................... 12\n1. Introduction\n\n[RFC6530] introduced the framework for Internationalized Email Addresses. To make such addresses more widely accepted, the changes to various protocols need to be introduced.\n\nThis document describes an Extensible Provisioning Protocol (EPP) extension that permits usage of Internationalized Email Addresses in the EPP protocol and specifies the terms when it can be used by EPP clients and servers. A new form of EPP extension, referred to as a Functional Extension, is defined and used to apply the rules for the handling of email address elements in all of the [RFC5730] extensions negotiated in the EPP session, which include the object and command-responses extensions. The described mechanism can be applied to any object or command-response extension that uses an email address.\n\nThe Extensible Provisioning Protocol (EPP) specified in [RFC5730] is a base document for object management operations and an extensible framework that maps protocol operations to objects. The specifics of various objects managed via EPP is described in separate documents. This document is only referring to an email address as a property of a managed object, such as the <contact:email> element in the EPP contact mapping [RFC5733] or the <org:email> element in the EPP organization mapping [RFC8543], and command-response extensions applied to a managed object.\n\n1.1. Conventions Used in This Document\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"NOT RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.\n\n2. Migrating to Newer Versions of This Extension\n\nServers that implement this extension SHOULD provide a way for clients to progressively update their implementations when a new version of the extension is deployed. A newer version of the extension is expected to use an XML namespace with a higher version number than the prior versions.\n3. Email Address Specification\n\nSupport of non-ASCII email address syntax is defined in RFC 6530 [RFC6530]. This mapping does not prescribe minimum or maximum lengths for character strings used to represent email addresses. The exact syntax of such addresses is described in Section 3.3 of [RFC6531]. The validation rules introduced in RFC 6531 are considered to be followed.\n\nThe definition of email address in the EPP RFCs, including Section 2.6 of [RFC5733] and Section 4.1.2, 4.2.1, and 4.2.5 of [RFC8543], references [RFC5322] for the email address syntax. The XML schema definition in Section 4 of [RFC5733] and Section 5 of [RFC8543] defines the \"email\" element using the type \"eppcom:minTokenType\", which is defined in Section 4.2 of [RFC5730] as an XML schema \"token\" type with minimal length of one. The XML schema \"token\" type will fully support the use of EAI addresses, so the primary application of the EAI extension is to apply the use of [RFC6531] instead of [RFC5322] for the email address syntax. Other EPP extensions may follow the formal syntax definition using the XML schema type \"eppcom:minTokenType\" and the [RFC5322] format specification, where this extension applies to all EPP extensions with the same or similar definitions.\n\nThe email address format is formally defined in Section 3.4.1 of [RFC5322], which only consists of printable US-ASCII characters for both the local-part and the domain ABNF rules. [RFC6531] extends the Mailbox, Local-part and Domain ABNF rules in [RFC5321] to support \"UTF8-non-ascii\", defined in Section 3.1 of [RFC6532], for the local-part and U-label, defined in Section 2.3.2.1 of [RFC5890], for the domain. By applying the syntax rules of [RFC5322], the EPP extensions will change from supporting only ASCII characters to supporting Internationalized characters both in the email address local-part and domain-part.\n\n4. Functional Extension\n\n[RFC5730] defines three types of extensions at the protocol, object, and command-response level, which impact the structure of the EPP messages. A Functional Extension applies a functional capability to an existing set of EPP extensions and properties. The scope of the applicable EPP extensions and applicable extension properties are defined in the Functional Extension along with the requirements for the servers and clients that support it. The Functional Extension needs to cover the expected behavior of the supporting client or server when interacting with an unsupporting client or server. Negotiating support for a Functional Extension is handled using the EPP Greeting and EPP Login services.\n5. Internationalized Email Addresses (EAI) Functional Extension\n\n5.1. Scope of Functional Extension\n\nThe functional extension applies to all object extensions and command-response extensions negotiated in the EPP session that include email address properties. Examples include the <contact:email> element in the EPP contact mapping [RFC5733] or the <org:email> element in the EPP organization mapping [RFC8543]. All registry zones (e.g., top-level domains) authorized for the client in the EPP session apply. There is no concept of a per-client, per-zone, per-extension, or per-field setting that is used to indicate support for EAI, but instead it’s a global setting that applies to the EPP session.\n\n5.2. Signaling Client and Server Support\n\nThe client and the server can signal support for the functional extension using a namespace URI in the login and greeting extension services respectively. The namespace URI \"urn:ietf:params:xml:ns:epp:eai-1.0\" is used to signal support for the functional extension. The client includes the namespace URI in an <svcExtension> <extURI> element of the [RFC5730] <login> Command. The server includes the namespace URI in an <svcExtension> <extURI> element of the [RFC5730] Greeting.\n\n5.3. Functional Extension Behavior\n\n5.3.1. EAI Functional Extension Negotiated\n\nIf both client and server have indicated the support of the EAI addresses during the session establishment, it implies possibility to process the EAI address in any message having an email property during the established EPP session. Below are the server and client obligations when the EAI extension has been successfully negotiated in the EPP session.\n\nThe server MUST satisfy the following obligations when the EAI extension has been negotiated:\n\n* Accept EAI compatible addresses for all email properties in the EPP session negotiated object extensions and command-response extensions. For example the <contact:email> element in [RFC5733] and the <org:email> element in [RFC8543].\n\n* Accept EAI compatible addresses for all registry zones (e.g., top-level domains) authorized for the client in the EPP session.\n* Email address validation based on EAI validation rules defined in Section 3\n\n* Storage of email properties that support internationalized characters.\n\n* Return EAI compatible addresses for all email properties in the EPP responses.\n\nThe client MUST satisfy the following obligations when THE EAI extension has been negotiated:\n\n* Provide EAI compatible addresses for all e-mail properties in the EPP session negotiated object extensions and command-response extensions. For example the <contact:email> element in [RFC5733] and the <org:email> element in [RFC8543].\n\n* Provide EAI compatible addresses for all registry zones (e.g., top-level domains) authorized for the client in the EPP session.\n\n* Accept EAI compatible addresses in the EPP responses for all email properties in the EPP session negotiated object extensions and command-response extensions.\n\n5.3.2. EAI Functional Extension Not Negotiated\n\nThe lack of EAI support can cause data and functional issues, so an EAI supporting client or server needs to handle cases where the opposite party doesn’t support EAI. Below are the server and client obligations when the EAI extension is not negotiated due to the lack of support by the peer.\n\nThe EAI supporting server MUST satisfy the following obligations when the client does not support the EAI extension:\n\n* When the email property is required in the EPP command, the server SHOULD validate the email property sent by the client using the ASCII email validation rules.\n\n* When the email property is optional in the EPP command, if the client supplies the email property the server SHOULD validate the email property using the ASCII email validation rules.\n\n* When the email property is required in the EPP response, the server MUST validate whether the email property is an EAI address and if so return the error code 2308 \"Data management policy violation\".\n* When the email property is optional in the EPP response and is provided, the server MUST validate whether the email property is an EAI address and if so return the error code 2308 \"Data management policy violation\".\n\nThe EAI supporting client MUST satisfy the following obligations when the server does not support the EAI extension:\n\n* When the email property is required in the EPP command and the email property is an EAI address, the client MUST provide an ASCII email address. The provided email address should provide a way to contact the registrant. It can be a secondary ASCII email address or registrar-provided proxy email address.\n\n* When the email property is optional in the EPP command and the email property is an EAI address with no alternative ASCII address, the client SHOULD omit the email property. If the email property is provided, the client MUST provide an ASCII email address. The provided email address should provide a way to contact the registrant. It can be a secondary ASCII email address or registrar-provided proxy email address.\n\n6. IANA Considerations\n\n6.1. XML Namespace\n\nThis document uses URNs to describe XML namespaces and XML schemas conforming to a registry mechanism described in RFC 3688 [RFC3688]. The following URI assignment should be made by IANA:\n\nRegistration request for the eai namespace:\n\nURI: urn:ietf:params:xml:ns:epp:eai-1.0\nRegistrant Contact: IESG\nXML: None. Namespace URIs do not represent an XML specification.\n\nRegistration request for the eai XML Schema:\n\nRegistrant Contact: IESG\nXML: See the \"Formal Syntax\" section of this document.\n\n6.2. EPP Extension Registry\n\nThe EPP extension described in this document should be registered by IANA in the \"Extensions for the Extensible Provisioning Protocol (EPP)\" registry described in RFC 7451 [RFC7451]. The details of the registration are as follows:\n7. Implementation Status\n\nNote to RFC Editor: Please remove this section and the reference to RFC 7942 [RFC7942] before publication.\n\nThis section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in RFC 7942 [RFC7942]. The description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist.\n\nAccording to RFC 7942 [RFC7942], \"this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit\".\n\n7.1. Verisign EPP SDK\n\nOrganization: Verisign Inc.\n\nName: Verisign EPP SDK\n\nDescription: The Verisign EPP SDK includes both a full client implementation and a full server stub implementation of draft-ietf-regext-epp-eai.\n\nLevel of maturity: Development\n\nCoverage: All aspects of the protocol are implemented.\n8. Security Considerations\n\nRegistries SHOULD validate the domain names syntax in the provided email addresses to reduce the risk of future usability errors. It is RECOMMENDED to validate all code points in the domain names according to IDNA2008 [RFC5892].\n\n9. Acknowledgments\n\nThe authors would like to thank Alexander Mayrhofer, Gustavo Lozano, Jody Kolker, John Levine, Klaus Malorny, Marco Schrieck, Mario Loffredo, Patrick Mevzek, Scott Hollenbeck, Taras Heichenko, and Thomas Corte for their careful review and valuable comments.\n\n10. References\n\n10.1. Normative References\n\n\n10.2. Informative References\n\n\nAppendix A. Change History\nA.1. Change from 00 to 01\n\n1. Changed from update of RFC 5733 to use the \"Placeholder Text and a New Email Element\" EPP Extension approach.\n\nA.2. Change from 01 to 02\n\n1. Fixed the XML schema and the XML examples based on validating them.\n\n2. Added James Gould as co-author.\n\n3. Updated the language to apply to any EPP object mapping and to use the EPP contact mapping as an example.\n\n4. Updated the structure of document to be consistent with the other Command-Response Extensions.\n\n5. Replaced the use of \"eppEAI\" in the XML namespace and the XML namespace prefix with \"eai\".\n\n6. Changed to use a pointed XML namespace with \"0.2\" instead of \"1.0\".\n\nA.3. Change from 02 to 03\n\n1. The approach has changed to use the concept of Functional EPP Extension.\n\n2. The examples are removed\n\nA.4. Change from 03 to 04\n\n1. More detailed reference to email syntax is provided\n\n2. The shortened eai namespace reference is removed\n\nA.5. Change from 04 to the regext 01 version\n\n1. Provided the recommended placeholder value\n\nA.6. Change from the regext 01 to regext 02 version\n\n1. Removed the concept of the placeholder value\n\nA.7. Change from the regext 02 to regext 03 version\n1. Changed to use a pointed XML namespace with \"0.3\" instead of \"0.2\".\n\n2. Some wording improvements\n\nA.8. Change from the regext 03 to regext 04 version\n\n1. Some nitpicking\n\nA.9. Change from the regext 04 to regext 05 version\n\n1. Some nitpicking\n\n2. The \"Implementation considerations\" section is removed\n\nA.10. Change from the regext 05 to regext 06 version\n\n1. Some nitpicking\n\nA.11. Change from the regext 06 to regext 07 version\n\n1. Namespace version set to 1.0\n\nA.12. Change from the regext 07 to regext 08 version\n\n1. Information about implementations is provided.\n\n2. Acknowledgments section is added.\n\n3. Reference to RFC 7451 is moved to Informative.\n\n4. IPR information is provided\n\n5. Sections are reordered to align with the other regext documents\n\nAuthors’ Addresses\n\nDmitry Belyavskiy\n8 marta st.\nMoscow\n127083\nRussian Federation\nPhone: +7 916 262 5593\nEmail: beldmit@gmail.com\nUsing JSContact in Registration Data Access Protocol (RDAP) JSON Responses\n\ndraft-ietf-regext-rdap-jscontact-12\n\nAbstract\n\nThis document describes an RDAP extension which represents entity contact information in JSON responses using JSContact.\n\nStatus of This Memo\n\nThis Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.\n\nInternet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.\n\nInternet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as \"work in progress.\"\n\nThis Internet-Draft will expire on 3 November 2022.\n\nCopyright Notice\n\nCopyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved.\n\nThis document is subject to BCP 78 and the IETF Trust’s Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.\nTable of Contents\n\n1. Introduction ............................................. 3\n 1.1. Rationale ........................................... 3\n 1.2. Conventions Used in This Document ................. 3\n2. JSContact ................................................. 4\n3. Using JSCard objects in RDAP Responses .................. 4\n 3.1. RDAP Query Parameters ............................... 10\n4. Transition Considerations ................................. 10\n 4.1. RDAP Features Supporting a Transition Process ... 10\n 4.1.1. Notices and Link Relationships ............... 10\n 4.1.2. rdapConformance Property .................... 11\n 4.1.3. Query Parameters ............................. 11\n 4.2. Transition Procedure ................................ 11\n 4.2.1. Goals .......................................... 11\n 4.2.2. Transition Stages ................................ 11\n 4.2.2.1. Stage 1: only jCard provided .......... 12\n 4.2.2.2. Stage 2: jCard sunset .................. 12\n 4.2.2.3. Stage 3: jCard deprecation ............ 13\n 4.2.2.4. Stage 4: jCard deprecated ............. 15\n 4.2.2.5. Length ..................................... 15\n5. Implementation Status .................................... 15\n 5.1. IIT-CNR/Registro.it RDAP Server .................... 15\n 5.2. IIT-CNR/Registro.it RDAP Client .................... 16\n 5.3. client.rdap.org .................................... 16\n 5.4. CentralNic Registry ................................ 16\n6. IANA Considerations ..................................... 17\n7. Security Considerations .................................. 17\n8. Acknowledgements ........................................ 17\n9. References ................................................. 17\n 9.1. Normative References ................................ 17\n 9.2. Informative References ............................. 19\nAppendix A. jCard-JSContact Mapping ........................ 19\nAppendix B. Change Log ..................................... 21\n B.1. Change from 00 to 01 ................................ 21\n B.2. Change from 01 to 02 ................................ 21\n B.3. Change from 02 to 03 ................................ 22\n B.4. Change from 03 to 04 ................................ 22\n B.5. Initial WG version .................................. 22\n B.6. Change from 00 to 01 ................................ 22\n B.7. Change from 01 to 02 ................................ 22\n B.8. Change from 02 to 03 ................................ 22\n B.9. Change from 03 to 04 ................................ 22\n B.10. Change from 04 to 05 ............................... 23\n B.11. Change from 05 to 06 ............................... 23\n B.12. Change from 06 to 07 ............................... 23\n B.13. Change from 07 to 08 ............................... 23\n B.14. Change from 08 to 09 ............................... 23\n1. Introduction\n\nThis document specifies an extension to the Registration Data Access Protocol (RDAP) that allows RDAP servers to use JSContact [I-D.ietf-calext-jscontact] to represent the contact information associated with entities in RDAP responses, instead of jCard [RFC7095]. It also describes the process by which an RDAP server can transition from jCard to JSContact. RDAP query and response extensions are defined to facilitate the transition process.\n\n1.1. Rationale\n\nAccording to the feedback from RDAP Pilot Working Group [RDAP-PILOT-WG], a group of RDAP server implementers representing registries and registrars of generic TLDs, the most commonly raised implementation concern, for both servers and client implementers, related to the use of jCard [RFC7095] to represent the contact information associated with entities. Working Group members reported jCard to be unintuitive, complicated to implement for both clients and servers, and incompatible with best practices for RESTful APIs.\n\nJSContact [I-D.ietf-calext-jscontact] provides a simpler and more efficient representation for contact information with regard to time and effort saved in processing it. In addition, similarly to jCard, it provides a means to represent internationalised and unstructured contact information. Support for internationalised contact information has been recognised being necessary to facilitate the future internationalisation of registration data directory services.\n\n1.2. Conventions Used in This Document\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"NOT RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.\n2. JSContact\n\nThe JSContact specification defines a data model and JSON representation of contact information that can be used for data storage and exchange in address book or directory applications. It aims to be an alternative to the vCard data format [RFC6350] and to be unambiguous, extendable and simple to process. In contrast with jCard, it is not a direct mapping from the vCard data model and expands semantics where appropriate.\n\nThe JSContact specification declares two main object types: \"Card\", which represents a single contact card, and \"CardGroup\" which represents a collection of Card objects. For the purpose of this document, only Card objects are considered. To avoid confusion, in the following of this document, the term \"JSCard\" is used to refer to \"JSContact Card\".\n\nJSCard differs from jCard in that it:\n\n* follows an object-oriented rather than array-oriented approach;\n* is simple to process;\n* requires no extra work in serialization/deserialization from/to a data model;\n* includes no \"jagged\" arrays;\n* prefers maps rather than arrays to implement collections.\n\n[I-D.ietf-calext-jscontact-vcard] provides informational guidance on the conversion of jCard into JSCard, and vice versa. Appendix A shows JSContact counterparts for the most commonly used jCard properties in an RDAP response.\n\n3. Using JSCard objects in RDAP Responses\n\nEntity objects in RDAP responses MAY include a \"jscard_0\" property whose value is a JSCard object instead of the \"vCardArray\" property defined in [RFC9083].\n\nServers returning the \"jscard_0\" property in their response MUST include \"jscard_0\" in the \"rdapConformance\" array.\n\nThe JSCard \"uid\" property SHOULD contain the same value as the RDAP \"handle\" property.\n\nSince most of the JSCard collections are represented as maps, map keys must be defined. To aid interoperability, RDAP providers are RECOMMENDED to use as map keys the following string values and labels defined in [RFC5733]:\n\nLoffredo & Brown Expires 3 November 2022 [Page 4]\n* \"org\" in the \"organizations\" map when there is a single <contact:org> element. If both internationalised and localized forms exist, the key MUST be used for the internationalised form;\n* \"addr\" in the \"addresses\" map when there is a single <contact:addr> element. If both internationalised and localized forms exist, the key MUST be used for the internationalised form;\n* \"email\" in the \"emails\" map for the <contact:email> element;\n* \"voice\" in the \"phones\" map for the <contact:voice> element;\n* \"fax\" in the \"phones\" map for the <contact:fax> element.\n\nIf present, the localized versions of name, organization and postal address MUST be inserted into the \"localizations\" map. The following is an elided example of an RDAP entity lookup response including a JSCard object that presents the \"localizations\" map (See PDF for non-ASCII character string).\n\n```json\n\"jscard_0\": {\n \"@type\": \"Card\",\n \"uid\": \"7e0636f5-e48f-4a32-ab96-b57e9c07c7aa\",\n \"fullName\": \"Vasya Pupkin\",\n \"organizations\": {\n \"org\": {\n \"@type\": \"Organization\",\n \"name\": \"My Company\"\n }\n },\n \"addresses\": {\n \"addr\": {\n \"@type\": \"Address\",\n \"street\": [ {\n \"@type\": \"StreetComponent\",\n \"value\": \"1 Street\"\n }, {\n \"@type\": \"StreetComponent\",\n \"type\": \"postOfficeBox\",\n \"value\": \"01001\"\n } ],\n \"locality\": \"Kyiv\",\n \"countryCode\": \"UA\"\n }\n },\n \"localizations\": {\n \"ua\": {\n \"/jscard_0/addresses/addr\": {\n \"@type\": \"Address\",\n \"street\": [ {\n \n```\n\"type\" : \"StreetComponent\",\n\"value\" : \"1, \"\n}, {\n \"type\" : \"postOfficeBox\",\n \"value\" : \"01001\"\n} ],\n\"locality\" : \"\",\n\"countryCode\" : \"UA\"\n},\n\"jscard_0/fullName\" : \"\",\n\"jscard_0/organizations/org\" : {\n@type\" : \"Organization\",\n\"name\" : \"\"\n}\n}\n}\n...\n\nFigure 1: Example of handling localizations in JSContact\n\nImplementers MAY use different mapping schemes to define keys for additional entries of the aforementioned maps or others. For example, a mapping scheme may consist in using a trivial sequential number (e.g. \"url-1\", \"url-2\", etc.)\n\nThe following is an example of an RDAP entity including a JSCard object that has been converted from the example in section 5.1 of [RFC9083].\n\n{\n \"rdapConformance\": [\n \"rdap_level_0\",\n \"jscard_0\"\n ],\n \"objectClassName\" : \"entity\",\n \"handle\": \"XXXX\",\n \"jscard_0\": {\n \"@type\": \"Card\",\n \"uid\": \"XXXX\",\n \"fullName\": \"Joe User\",\n \"name\": {\n \"@type\": \"Name\",\n \"components\": [\n \n \"@type\": \"NameComponent\",\n ]\n }\n }\n}\n\"type\": \"surname\",\n\"value\": \"User\"\n},\n{\n\"@type\": \"NameComponent\",\n\"type\": \"personal\",\n\"value\": \"Joe\"\n},\n{\n\"@type\": \"NameComponent\",\n\"type\": \"suffix\",\n\"value\": \"ing. jr\"\n},\n{\n\"@type\": \"NameComponent\",\n\"type\": \"suffix\",\n\"value\": \"M.Sc.\"\n}\n]\n},\n\"kind\": \"individual\",\n\"preferredContactLanguages\": {\n\"fr\": {\n\"@type\": \"ContactLanguage\",\n\"pref\": 1\n},\n\"en\": {\n\"@type\": \"ContactLanguage\",\n\"pref\": 2\n}\n},\n\"organizations\": {\n\"org\": {\n\"@type\": \"Organization\",\n\"name\": \"Example\"\n}\n},\n\"titles\": {\n\"title\": {\n\"@type\": \"Title\",\n\"title\": \"Research Scientist\"\n},\n\"role\": {\n\"@type\": \"Title\",\n\"title\": \"Project Lead\"\n}\n},\n\"addresses\": {\n\"addr\": {\n \"@type\": \"Address\",\n \"contexts\": {\n \"work\": true\n },\n \"street\": [\n {\n \"@type\": \"StreetComponent\",\n \"type\": \"name\",\n \"value\": \"4321 Rue Somewhere\"\n },\n {\n \"@type\": \"StreetComponent\",\n \"type\": \"extension\",\n \"value\": \"Suite 1234\"\n }\n ],\n \"locality\": \"Quebec\",\n \"region\": \"QC\",\n \"postcode\": \"G1V 2M2\",\n \"country\": \"Canada\",\n \"countryCode\": \"CA\",\n \"coordinates\": \"geo:46.772673,-71.282945\",\n \"timeZone\": \"Etc/GMT+5\"\n},\n\"home\": {\n \"@type\": \"Address\",\n \"contexts\": {\n \"private\": true\n },\n \"fullAddress\": \"123 Maple Ave\\nSuite 90001\\nVancouver\\nBC\\n1239\\n\"\n},\n\"phones\": {\n \"voice\": {\n \"@type\": \"Phone\",\n \"contexts\": {\n \"work\": true\n },\n \"features\": {\n \"voice\": true,\n \"cell\": true,\n \"video\": true,\n \"text\": true\n },\n \"pref\": 1,\n \"phone\": \"tel:+1-555-555-1234;ext=102\"\n }\n}\n\n\n```\n{\n \"emails\": {\n \"email\": {\n \"@type\": \"EmailAddress\",\n \"contexts\": {\n \"work\": true\n },\n \"email\": \"joe.user@example.com\"\n }\n },\n \"online\": {\n \"key\": {\n \"@type\": \"Resource\",\n \"contexts\": {\n \"work\": true\n },\n \"type\": \"publicKey\",\n \"resource\": \"http://www.example.com/joe.user/joe.asc\"\n },\n \"url\": {\n \"@type\": \"Resource\",\n \"contexts\": {\n \"private\": true\n },\n \"type\": \"uri\",\n \"resource\": \"http://example.org\"\n }\n },\n \"roles\": [\"registrar\"],\n \"publicIds\": [\n {\n \"type\": \"IANA Registrar ID\",\n \"identifier\": \"1\"\n }\n ],\n \"remarks\": [\n {\n \"description\": [\n \"She sells sea shells down by the sea shore.\",\n \"Originally written by Terry Sullivan.\"\n ]\n }\n ],\n \"links\": [\n {\n \"value\": \"http://example.com/entity/XXXX\",\n \"rel\": \"self\",\n```\n\"href\":\"http://example.com/entity/XXXX\",\n\"type\" : \"application/rdap+json\"\n}\n\n\"events\": [ \n{ \n\"eventAction\":\"registration\",\n\"eventDate\":\"1990-12-31T23:59:59Z\"\n }\n],\n\n\"asEventActor\": [ \n{ \n\"eventAction\":\"last changed\",\n\"eventDate\":\"1991-12-31T23:59:59Z\"\n }\n]\n}\n\nFigure 2: Example of using JSContact in RDAP response\n\n3.1. RDAP Query Parameters\n\nTwo new query parameters are defined for the purpose of this document.\n\nThe query parameters are OPTIONAL extensions of path segments defined in [RFC9082]. They are as follows:\n\n* \"jscard\": a boolean value that allows a client to request the \"jscard_0\" property in the RDAP response;\n* \"jcard\": a boolean value that allows a client to request the \"vcardArray\" property in the RDAP response.\n\nThese parameters are furtherly explained in Section 4.\n\n4. Transition Considerations\n\n4.1. RDAP Features Supporting a Transition Process\n\n4.1.1. Notices and Link Relationships\n\nRDAP allows servers to communicate service information to clients through notices. According to Section 4.3 of [RFC9083], an RDAP response may contain one or more notice objects. Each notice may include a set of link objects, which can be used to provide clients with references and documentation. These link objects may have a \"rel\" property which defines the relationship type, as described in [RFC8288], Section 4. The transition process outlined in this\ndocument uses two link relation types, namely \"related\" and \"alternate\", described in [RFC8288].\n\n4.1.2. rdapConformance Property\n\nThe information about the specifications used in the construction of the response is also described by the strings which appear in the \"rdapConformance\" property of the RDAP response.\n\n4.1.3. Query Parameters\n\nClients can ask servers to use the query parameters defined in Section 3.1 in accordance with [RFC9082].\n\n4.2. Transition Procedure\n\nThe principles of the procedure for jCard to JSCard transition are based on the best practices in [API-DEPRECATION].\n\nThe procedure consists of four contiguous stages. During the procedure, the presence of \"jscard_0\" tag in the rdapConformance array indicates that JSCard is returned instead of jCard. The date and time format used to notify clients about the stages of this procedure is defined in [RFC3339].\n\n4.2.1. Goals\n\nThe procedure described in this document aims to achieve the following goals:\n\n* only one contact representation would be included in the response;\n* the response would always be compliant to [RFC9083] because:\n - being the \"jscard_0\" property a response extension, its presence would be signaled by the \"jscard_0\" conformance tag;\n - being \"vcardArray\" property optional in a response, its absence would be allowed;\n* clients would be informed about the transition timeline;\n* the backward compatibility would be guaranteed throughout the transition;\n* servers and clients could execute their transitions independently.\n\n4.2.2. Transition Stages\n4.2.2.1. Stage 1: only jCard provided\n\nThis stage corresponds to providing jCard as the default contact card [RFC9083]. The RDAP server is not able to provide an alternate contact card. The rdapConformance array MUST NOT contain the \"jcard_0\" tag.\n\n4.2.2.2. Stage 2: jCard sunset\n\nDuring this stage, the server uses jCard by default, but the RDAP server will return JSCard if the client sets the query parameter \"jscard\" to 1/true/yes. The rdapConformance array MUST contain the \"jcard_0\" tag if JSCard is returned.\n\nFrom this stage on, the RDAP server MUST include the \"jcard_0\" tag in the rdapConformance array of the help response to signal clients that JSCard can be returned instead of jCard.\n\nThe RDAP server SHOULD include a notice titled \"jCard sunset end\". Such a notice includes a description reporting the jCard sunset end date and time and two OPTIONAL links:\n\n* \"related\": a link to a URI-identified resource documenting the transition procedure;\n* \"alternate\": if JSCard is not requested, a link to an alternate result view identified by the current query string plus the parameter \"jscard\" set to 1/true/yes (Figure 3); otherwise, only the \"related\" link can be provided (Figure 4).\n\n\"notices\": [\n{\n \"title\": \"jCard sunset end\",\n \"description\": \"[2022-07-01T00:00:00Z]\",\n \"links\": [\n {\n \"value\": \"http://example.net/entity/XXXX\",\n \"rel\": \"related\",\n \"type\": \"text/html\",\n \"href\": \"http://www.example.com/jcard_deprecation.html\"\n },\n {\n \"value\": \"http://example.net/entity/XXXX\",\n \"rel\": \"alternate\",\n \"type\": \"application/rdap+json\",\n \"href\": \"http://example.net/entity/XXXX?jscard=1\"\n }\n ]\n} ]\n4.2.2.3. Stage 3: jCard deprecation\n\nThis stage corresponds to the provisioning of JSCard by default, but the RDAP will return jCard if the client sets the query parameter \"jcard\" to 1/true/yes. The rdapConformance array contains the \"jscard_0\" tag unless jCard is returned. The \"jcard\" query parameter MUST be ignored.\n\nThe RDAP server SHOULD return a notice titled \"jCard deprecation end\". Such a notice includes a description reporting the jCard deprecation end date and time and two OPTIONAL links:\n\n* \"related\": a link to a URI-identified resource documenting the transition procedure;\n* \"alternate\": if jCard is not requested, a link to an alternate result view identified by the current query string plus the parameter \"jcard\" set to 1/true/yes (Figure 5); otherwise, a link to the result view identified by the current query string without the parameter \"jcard\" (Figure 6).\n\"notices\": [\n {\n \"title\": \"jCard deprecation end\",\n \"description\": [\"2022-12-31T23:59:59Z\"],\n \"links\": [\n {\n \"value\": \"http://example.net/entity/XXXX\",\n \"rel\": \"related\",\n \"type\": \"text/html\",\n \"href\": \"http://www.example.com/jcard_deprecation.html\"\n },\n {\n \"value\": \"http://example.net/entity/XXXX\",\n \"rel\": \"alternate\",\n \"type\": \"application/rdap+json\",\n \"href\": \"http://example.net/entity/XXXX?jcard=1\"\n }\n ]\n }\n]\n\nFigure 5: jCard deprecation - jCard not requested\n\n\"notices\": [\n {\n \"title\": \"jCard deprecation end\",\n \"description\": [\"2022-12-31T23:59:59Z\"],\n \"links\": [\n {\n \"value\": \"http://example.net/entity/XXXX?jcard=1\",\n \"rel\": \"related\",\n \"type\": \"text/html\",\n \"href\": \"http://www.example.com/jcard_deprecation.html\"\n },\n {\n \"value\": \"http://example.net/entity/XXXX?jcard=1\",\n \"rel\": \"alternate\",\n \"type\": \"application/rdap+json\",\n \"href\": \"http://example.net/entity/XXXX\"\n }\n ]\n }\n]\n\nFigure 6: jCard deprecation - jCard requested\n4.2.2.4. Stage 4: jCard deprecated\n\nThis stage corresponds to providing JSCard as default contact card. The RDAP server is not able to provide an alternate contact card. The rdapConformance array always contains \"jscard_0\" tag. The RDAP server doesn't include any notice about the jCard deprecation process. Both \"jscard\" and \"jcard\" query parameters MUST be ignored.\n\n4.2.2.5. Length\n\nThe length of both jCard sunset and jCard deprecation periods are not fixed by this specification. Best practices in REST API deprecation suggest that, depending on the deprecated API’s reach, user base and service offering, a convenient time could be anywhere between 3 - 8 months. Anyway, RDAP providers are RECOMMENDED to monitor the server log to figure out whether declared times need to be changed to meet client requirements.\n\n5. Implementation Status\n\nNOTE: Please remove this section and the reference to RFC 7942 prior to publication as an RFC.\n\nThis section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in RFC 7942 [RFC7942]. The description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist.\n\nAccording to RFC 7942, \"this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit\".\n\n5.1. IIT-CNR/Registro.it RDAP Server\n\n* Responsible Organization: Institute of Informatics and Telematics of National Research Council (IIT-CNR)/Registro.it\n* Location: https://rdap.pubtest.nic.it/\n* Description: This implementation includes support for RDAP queries using data from the public test environment of .it ccTLD.\n* Level of Maturity: This is an \"alpha\" test implementation.\n* Coverage: This implementation includes all of the features described in this specification.\n* Contact Information: Mario Loffredo, mario.loffredo@iit.cnr.it\n\n5.2. IIT-CNR/Registro.it RDAP Client\n\n* Responsible Organization: Institute of Informatics and Telematics of National Research Council (IIT-CNR)/Registro.it\n* Location: https://web-rdap.pubtest.nic.it/\n* Description: This is a Javascript web-based RDAP client. RDAP responses are retrieved from RDAP servers by the browser, parsed into an HTML representation, and displayed in a format improving the user experience. RDAP responses containing JSCard objects are handled identically to those containing jCard objects. Raw versions of RDAP responses including either jCard or JSCard objects are provided.\n* Level of Maturity: This is an \"alpha\" test implementation.\n* Coverage: This implementation includes all of the features described in this specification.\n* Contact Information: Francesco Donini, francesco.donini@iit.cnr.it\n\n5.3. client.rdap.org\n\n* Location: https://client.rdap.org/\n* Description: This is a web-based \"single page\" RDAP client. RDAP responses are retrieved from RDAP servers by the browser, and parsed into an HTML representation. RDAP responses containing JSCard objects are handled identically to those containing jCard objects.\n* Level of Maturity: This is an \"alpha\" test implementation.\n* Coverage: This implementation implements client support for parsing JSCard objects in RDAP responses.\n* Contact Information: Gavin Brown, feedback@rdap.org\n\n5.4. CentralNic Registry\n\n* Responsible Organization: CentralNic Group PLC\n* Location: https://rdap.centralnic.com/{tld}\n* Description: This server is the product RDAP service for all top-level domains on the CentralNic registry platform.\n* Level of Maturity: Production quality.\n* Coverage: This implementation includes all of the features described in this specification.\n* Contact Information: support@centralnic.com\n6. IANA Considerations\n\nIANA is requested to register the following values in the RDAP Extensions Registry:\n\n* Extension identifier: jscard_0\n* Registry operator: Any\n* Published specification: This document.\n* Contact: IETF <iesg@ietf.org>\n* Intended usage: This extension represents a contact card provided in an RDAP response according to the JSContact specification [I-D.ietf-calext-jscontact].\n\n7. Security Considerations\n\nUnlike jCard, the formatted name as well as any other personally identifiable information is not required in JSCard. The only mandatory property, namely \"uid\", is not a sensitive information as it happens, instead, for the \"fn\" property in jCard. Therefore, redacted properties can be merely excluded without using placeholder values. This means that, with reference to what is described in [I-D.ietf-regext-rdap-redacted], only the \"Removal\" method can be used for redacting JSContact properties whereas the \"Empty Value\" is also used for redacting jCard.\n\n8. Acknowledgements\n\nThe authors would like to acknowledge the following individuals for their contributions to this document: Jasdip Singh and Francesco Donini.\n\n9. References\n\n9.1. Normative References\n\n[I-D.ietf-calext-jscontact]\n\n[I-D.ietf-calext-jscontact-vcard]\nInternet-Draft Using JSContact in RDAP May 2022\n\n\nAppendix A. jCard-JSContact Mapping\n\nProvided that the keys defined in Section 3 are used for the \nJSContact maps, the mapping between the most commonly used jCard \nproperties in an RDAP response and their JSContact counterparts is \nshown in the following. The mapping is done through the use of a \nJSONPath expression [I-D.ietf-jsonpath-base].\n\njCard property: fn\nReference: Section 6.2.1 of [RFC6350]\nPath: $.vcardArray[1][?(@[0]=='fn')][3]\nJSContact property: fullName\nReference: Section 2.2.2 of [I-D.ietf-calext-jscontact]\nPath: $.jscard_0.fullName\n\njCard property: org\nReference: Section 6.6.4 of [RFC6350]\nPath: $.vcardArray[1][?(@[0]=='org')][3]\nJSContact property: Organization.name\nReference: Section 2.2.4 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.organizations.org.name\n\njCard property: tel with type=\"voice\"\nReference: Section 6.4.1 of [RFC6350]\nPath: $..vcardArray[1][?(@[1].type=='voice')][3]\nJSContact property: Phone.phone\nReference: Section 2.3.2 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.phones.voice.phone\n\njCard property: tel with type=\"fax\"\nReference: Section 6.4.1 of [RFC6350]\nPath: $..vcardArray[1][?(@[1].type=='fax')][3]\nJSContact property: Phone.phone\nReference: Section 2.3.2 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.phones.fax.phone\n\njCard property: email\nReference: Section 6.4.2 of [RFC6350]\nPath: $..vcardArray[1][?(@[0]=='email')][3]\nJSContact property: Email.email\nReference: Section 2.3.1 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.emails.email.email\n\njCard property: \"post office box\" component of adr\nReference: Section 6.3.1 of [RFC6350]\nPath: $..vcardArray[1][?(@[0]=='adr')][3][1]\nJSContact property: \"postOfficeBox\" StreetComponent of Address.street\nReference: Section 2.4.1 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.addresses.addr.street[?(@.type=='postOfficeBox')].value\n\njCard property: \"street address\" component of adr\nReference: Section 6.3.1 of [RFC6350]\nPath: $..vcardArray[1][?(@[0]=='adr')][3][2]\nJSContact property: \"name\" StreetComponent of Address.street\nReference: Section 2.4.1 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.addresses.addr.street[?(@.type=='name')].value\n\njCard property: \"locality\" component of adr\nReference: Section 6.3.1 of [RFC6350]\nPath: $..vcardArray[1][?(@[0]=='adr')][3][3]\nJSContact property: Address.locality\nReference: Section 2.4.1 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.addresses.addr.locality\n\njCard property: \"region\" component of adr\nReference: Section 6.3.1 of [RFC6350]\nPath: $..vcardArray[1][?(@[0]=='adr')][3][4]\nJSContact property: Address.region\nReference: Section 2.4.1 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.addresses.addr.region\n\njCard property: \"postal code\" component of adr\nReference: Section 6.3.1 of [RFC6350]\nPath: $..vcardArray[1][?(@[0]=='adr')][3][5]\nJSContact property: Address.postcode\nReference: Section 2.4.1 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.addresses.addr.postcode\n\njCard property: \"country name\" component of adr\nReference: Section 6.3.1 of [RFC6350]\nPath: $..vcardArray[1][?(@[0]=='adr')][3][6]\nJSContact property: Address.country\nReference: Section 2.4.1 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.addresses.addr.country\n\njCard property: \"cc\" parameter of adr\nReference: Section 3.1 of [RFC8605]\nPath: $..vcardArray[1][?(@[0]=='adr')][1].cc\nJSContact property: Address.countryCode\nReference: Section 2.4.1 of [I-D.ietf-calext-jscontact]\nPath: $..jscard_0.addresses.addr.countryCode\n\nAppendix B. Change Log\n\nB.1. Change from 00 to 01\n\n1. Changed category from \"Best Current Practice\" to \"Standards Track\"\n2. Replaced the example of Figure 2\n3. Changed the title of the \"Migration from JCard to JSCard\" section to \"Transition Considerations\"\n4. Added Section 3.1\n5. Updated Section 6\n6. Updated Section 7\n7. Rearranged the description of stage 1 in Section 4.2.2\n8. Changed the names of the transition stages 1 and 2\n9. Corrected Figure 3, Figure 5, Figure 6\n10. Changed the rdapConformance tag \"jscard_level_0\" to \"jscard\"\n11. Removed the \"Best Practices for deprecating a REST API features\" section, but added a useful reference.\n\nB.2. Change from 01 to 02\n1. Removed the sentence \"which cannot be represented using jCard\" in Section 1.1.\n\nB.3. Change from 02 to 03\n\n1. Updated section \"Conventions Used in This Document\".\n2. Updated the contact in \"IANA Considerations\" section.\n4. Added reference to RFC8174.\n5. Other minor edits.\n\nB.4. Change from 03 to 04\n\n1. Updated the reference draft-dalal-deprecation-header to draft-ietf-httpapi-deprecation-header.\n\nB.5. Initial WG version\n\n\nB.6. Change from 00 to 01\n\n1. Updated Section 3 and Figure 2.\n\nB.7. Change from 01 to 02\n\n1. Updated Section 2 and Figure 2.\n\nB.8. Change from 02 to 03\n\n1. Replaced references to obsolete RFC7482 and RFC7483 with RFC9082 and RFC9083.\n2. Updated Section 3 and Figure 2.\n\nB.9. Change from 03 to 04\n\n1. Changed the references to Internet Drafts.\n2. Added an example showing how localizations are treated in JSContact.\n3. Changed the position of section \"Goals\" in Section 4.2.\n4. Added three more implementations to Section 5.\n5. Changed the rdapConformance tag \"jcard\" to \"jscard_0\"\n6. Added clarifications addressing the feedback provided by Jasdip Singh about version -03.\n7. Added Section 8.\n8. Other minor edits.\nB.10. Change from 04 to 05\n\n1. Updated Figure 2 to make it compliant with draft-ietf-jmap-jscontact-09.\n\nB.11. Change from 05 to 06\n\n1. Reviewed the notices presented in Section 4.2.2.2 and Section 4.2.2.3.\n\nB.12. Change from 06 to 07\n\n1. Corrected the JSON Pointer expressions in Figure 1.\n2. Other minor edits.\n\nB.13. Change from 07 to 08\n\n1. Corrected a nit in Figure 1.\n2. Removed the reference to draft-ietf-httpapi-deprecation-header.\n3. Replaced the \"deprecation\" link relation type with \"related\".\n4. Moved the references to JSContact drafts to the \"Normative References\" section.\n\nB.14. Change from 08 to 09\n\n1. Updated the references to JSContact drafts due to the transfer from JMAP to CalExt.\n\nB.15. Change from 09 to 10\n\n1. Updated Figure 2 to make it compliant with draft-ietf-calext-jscontact-02.\n\nB.16. Change from 10 to 11\n\n1. Added Appendix \"jCard-JSContact Mapping\".\n\nB.17. Change from 11 to 12\n\n1. Renamed the \"jcard\" property to \"jcard_0\".\n2. Corrected JSONPath expressions in Appendix A.\n\nAuthors’ Addresses\nMario Loffredo \nIIT-CNR/Registro.it \nVia Moruzzi,1 \n56124 Pisa \nItaly \nEmail: mario.loffredo@iit.cnr.it \nURI: http://www.iit.cnr.it\n\nGavin Brown \nCentralNic Group plc \nSaddlers House, 44 Gutter Lane \nLondon \nEC2V 6BR \nUnited Kingdom \nPhone: +44 20 33 88 0600 \nEmail: gavin.brown@centralnic.com \nURI: https://www.centralnic.com\nFederated Authentication for the Registration Data Access Protocol (RDAP) using OpenID Connect\ndraft-ietf-regext-rdap-openid-13\n\nAbstract\n\nThe Registration Data Access Protocol (RDAP) provides \"RESTful\" web services to retrieve registration metadata from domain name and regional internet registries. RDAP allows a server to make access control decisions based on client identity, and as such it includes support for client identification features provided by the Hypertext Transfer Protocol (HTTP). Identification methods that require clients to obtain and manage credentials from every RDAP server operator present management challenges for both clients and servers, whereas a federated authentication system would make it easier to operate and use RDAP without the need to maintain server-specific client credentials. This document describes a federated authentication system for RDAP based on OpenID Connect.\n\nStatus of This Memo\n\nThis Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.\n\nInternet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.\n\nInternet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as \"work in progress.\"\n\nThis Internet-Draft will expire on 19 November 2022.\n\nCopyright Notice\n\nCopyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved.\nThis document is subject to BCP 78 and the IETF Trust’s Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.\n\nTable of Contents\n\n1. Introduction ......................................................... 3\n 1.1. Problem Statement ............................................. 3\n 1.2. Proposal ...................................................... 4\n2. Conventions Used in This Document ................................. 4\n3. Federated Authentication for RDAP .................................. 4\n 3.1. RDAP and OpenID Connect ..................................... 5\n 3.1.1. Terminology ............................................. 5\n 3.1.2. Overview ................................................. 5\n 3.1.3. RDAP Authentication and Authorization Steps ............ 6\n 3.1.3.1. Provider Discovery ................................ 7\n 3.1.3.2. Authentication Request ............................... 7\n 3.1.3.3. End-User Authorization ............................... 8\n 3.1.3.4. Authorization Response and Validation ............... 8\n 3.1.3.5. Token Processing ................................... 8\n 3.1.3.6. Delivery of User Information ......................... 8\n 3.1.4. Specialized Claims for RDAP ............................. 9\n 3.1.4.1. Stated Purposes ..................................... 9\n 3.1.4.2. Do Not Track ....................................... 10\n4. Protocol Parameters ................................................. 11\n 4.1. Data Structures ................................................ 11\n 4.1.1. Session ................................................ 11\n 4.1.2. Device Info ............................................. 12\n 4.1.3. OpenID Connect Configuration ............................ 13\n 4.2. Client Login .................................................. 14\n 4.2.1. End-User Identifier .................................... 14\n 4.2.2. OP Issuer Identifier ................................... 15\n 4.2.3. Login Response ......................................... 15\n 4.2.4. Clients with Limited User Interfaces ................... 17\n 4.2.4.1. UI-constrained Client Login ....................... 17\n 4.2.4.2. UI-constrained Client Login Polling ............... 19\n 4.3. RDAP Query Parameters ......................................... 19\n 4.3.1. RDAP Query Purpose ...................................... 20\n 4.3.2. RDAP Do Not Track ...................................... 20\n 4.4. Session Status ................................................. 20\n 4.5. Session Refresh ............................................... 22\n 4.6. Client Logout ................................................ 23\n 4.7. Parameter Processing ......................................... 25\n1. Introduction\n\nThe Registration Data Access Protocol (RDAP) provides \"RESTful\" web services to retrieve registration metadata from domain name and regional internet registries. RDAP allows a server to make access control decisions based on client identity, and as such it includes support for client identification features provided by the Hypertext Transfer Protocol (HTTP) [RFC7230].\n\nRDAP is specified in multiple documents, including \"HTTP Usage in the Registration Data Access Protocol (RDAP)\" [RFC7480], \"Security Services for the Registration Data Access Protocol (RDAP)\" [RFC7481], \"Registration Data Access Protocol Query Format\" [RFC9082], and \"JSON Responses for the Registration Data Access Protocol (RDAP)\" [RFC9083]. RFC 7481 describes client identification and authentication services that can be used with RDAP, but it does not specify how any of these services can (or should) be used with RDAP.\n\n1.1. Problem Statement\n\nThe traditional \"user name and password\" authentication method does not scale well in the RDAP ecosystem. Assuming that all domain name and address registries will eventually provide RDAP service, it is impractical and inefficient for users to secure login credentials from the hundreds of different server operators. Authentication methods based on user names and passwords do not provide information that describes the user in sufficient detail (while protecting the personal privacy of the user) for server operators to make fine-\ngrained access control decisions based on the user’s identity. The authentication system used for RDAP needs to address all of these needs.\n\n1.2. Proposal\n\nA basic level of RDAP service can be provided to users who possess an identifier issued by a recognized provider who is able to authenticate and validate the user. The identifiers issued by social media services, for example, can be used. Users who require higher levels of service (and who are willing to share more information about them self to gain access to that service) can secure identifiers from specialized providers who are or will be able to provide more detailed information about the user. Server operators can then make access control decisions based on the identification information provided by the user.\n\nA federated authentication system in which an RDAP server outsources identification and authentication services to a trusted OpenID Provider would make it easier to operate and use RDAP by re-using existing identifiers to provide a basic level of access. It can also provide the ability to collect additional user identification information, and that information can be shared with the consent of the user. This type of system allows an RDAP server to make access control decisions based on the nature of a query and the identity, authentication, and authorization information that is received from the OpenID Provider. This document describes a federated authentication system for RDAP based on OpenID Connect [OIDC] that meets all of these needs.\n\n2. Conventions Used in This Document\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"NOT RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.\n\n3. Federated Authentication for RDAP\n\nRDAP itself does not include native security services. Instead, RDAP relies on features that are available in other protocol layers to provide needed security services including access control, authentication, authorization, availability, data confidentiality, data integrity, and identification. A description of each of these security services can be found in \"Internet Security Glossary, Version 2\" [RFC4949]. This document focuses on a federated authentication system for RDAP that provides services for\nauthentication, authorization, and identification, allowing a server operator to make access control decisions. Section 3 of RFC 7481 [RFC7481] describes general considerations for RDAP access control, authentication, and authorization.\n\nThe traditional client-server authentication model requires clients to maintain distinct credentials for every RDAP server. This situation can become unwieldy as the number of RDAP servers increases. Federated authentication mechanisms allow clients to use one credential to access multiple RDAP servers and reduce client credential management complexity.\n\n3.1. RDAP and OpenID Connect\n\nOpenID Connect 1.0 [OIDCC] is a decentralized, single sign-on (SSO) federated authentication system that allows users to access multiple web resources with one identifier instead of having to create multiple server-specific identifiers. Users acquire identifiers from OpenID Providers, or OPs. Relying Parties, or RPs, are applications (such as RDAP) that outsource their user authentication function to an OP. OpenID Connect is built on top of the authorization framework provided by the OAuth 2.0 [RFC6749] protocol.\n\nThe OAuth authorization framework describes a method for users to access protected web resources without having to hand out their credentials. Instead, clients are issued Access Tokens by authorization servers with the permission of the resource owners. Using OpenID Connect and OAuth, multiple RDAP servers can form a federation and clients can access any server in the federation by providing one credential registered with any OP in that federation. The OAuth authorization framework is designed for use with HTTP and thus can be used with RDAP.\n\n3.1.1. Terminology\n\nThis document uses the terms \"client\" and \"server\" defined by RDAP [RFC7480]. An RDAP client performs the role of an OpenID Connect Core [OIDCC] Entity or End-User. An RDAP server performs the role of an OpenID Connect Core Relying Party (RP). Additional terms from Section 1.2 of the OpenID Connect Core specification are incorporated by reference.\n\n3.1.2. Overview\n\nAt a high level, RDAP authentication of a browser-like client using OpenID Connect requires completion of the following steps:\n1. An RDAP client sends an RDAP \"help\" query to an RDAP server to determine the type and capabilities of the OpenID Authorization Servers that are used by the RDAP server. This information is returned in the rdapConformance section of the response. A value of \"roidc1\" indicates support for the extension described in this specification. If one or more remote Authorization Servers are supported, the RDAP client SHOULD evaluate the additional information described in Section 4.1.3 in order to discover the capabilities of the RDAP server and optionally obtain the set of supported OPs.\n\n2. An RDAP client (acting as an OpenID End-User) sends an RDAP \"login\" request to an RDAP server as described in Section 4.2.\n\n3. The RDAP server (acting as an OpenID Relying Party (RP)) prepares an Authentication Request containing the desired request parameters.\n\n4. The RDAP server sends the RDAP client and Authentication Request to an Authorization Server operated by an OpenID Provider (OP) using an HTTP redirect.\n\n5. The Authorization Server authenticates the End-User.\n\n\n8. The RDAP server requests a response using the Authorization Code at the Token Endpoint.\n\n9. The RDAP server receives a response that contains an ID Token and Access Token in the response body.\n\n10. The RDAP server validates the ID Token and retrieves the claims associated with the End-User’s identity.\n\nThe RDAP server can then make identification, authorization, and access control decisions based on End-User identity information and local policies. Note that OpenID Connect describes different process flows for other types of clients, such as script-based or command line clients.\n\n3.1.3. RDAP Authentication and Authorization Steps\n\nEnd-Users MAY present an identifier (an OpenID) issued by an OP to use OpenID Connect with RDAP. If the RDAP server supports a default Authorization Server or End-User identifier discovery is not supported, the End-User identifier MAY be omitted. An OP SHOULD include support for the claims described in Section 3.1.4 to provide additional information needed for RDAP End-User authorization. OpenID Connect requires RPs to register with OPs to use OpenID Connect services for an End-User. The registration process is often completed using out-of-band methods, but it is also possible to use the automated method described by the \"OpenID Connect Dynamic Client Registration\" protocol [OIDCR]. The parties involved can use any\nmethod that is mutually acceptable.\n\n3.1.3.1. Provider Discovery\n\nAn RDAP server/RP needs to be able to map an End-User’s identifier to an OP. This can be accomplished using the OPTIONAL \"OpenID Connect Discovery\" protocol [OIDCD], but that protocol is not widely implemented. Out-of-band methods are also possible and can be more dependable. For example, an RP can support a limited number of OPs and maintain internal associations of those identifiers with the OPs that issued them.\n\nAlternatively, if mapping of an End-User’s identifier is not possible, or not supported by the RDAP server, the RDAP server SHOULD support explicit specification of a remote OP by the RDAP client in the form of a query parameter as described in Section 4.2.2. An RDAP server SHOULD provide information about its capabilities and supported OPs in the \"help\" query response in the \"openidcConfiguration\" data structure described in Section 4.1.3.\n\nAn RP can also ask an End-User to identify the OP that issued their identifier as part of an RDAP query workflow. In this case, the RP will need to maintain state for the association between the user’s identifier and the OP in order to process later queries that rely on passing the access token and user identifier as authorization parameters. An RDAP server MUST support at least one of these methods of OP discovery.\n\n3.1.3.2. Authentication Request\n\nOnce the OP is known, an RP MUST form an Authentication Request and send it to the OP as described in Section 3 of the OpenID Connect Core protocol [OIDCC]. The authentication path followed (authorization, implicit, or hybrid) will depend on the Authentication Request response_type set by the RP. The remainder of the processing steps described here assume that the Authorization Code Flow is being used by setting \"response_type=code\" in the Authentication Request.\n\nThe benefits of using the Authorization Code Flow for authenticating a human user are described in Section 3.1 of the OpenID Connect Core protocol. The Implicit Flow is more commonly used by clients implemented in a web browser using a scripting language; it is described in Section 3.2 of the OpenID Connect Core protocol. The Hybrid Flow (described in Section 3.3 of the OpenID Connect Core protocol) combines elements of the Authorization and Implicit Flows by returning some tokens from the Authorization Endpoint and others from the Token Endpoint.\nAn Authentication Request can contain several parameters. REQUIRED\nparameters are specified in Section 3.1.2.1 of the OpenID Connect\nCore protocol [OIDCC]. Apart from these parameters, it is\nRECOMMENDED that the RP include the optional \"login_hint\" parameter\nin the request, with the value being that of the \"id\" query parameter\nof the End-User’s RDAP \"login\" request, if provided. Passing the\n\"login_hint\" parameter allows a client to pre-fill login form\ninformation, so logging in can be more convenient for users. Other\nparameters MAY be included.\n\nThe OP receives the Authentication Request and attempts to validate\nit as described in Section 3.1.2.2 of the OpenID Connect Core\nprotocol [OIDCC]. If the request is valid, the OP attempts to\nauthenticate the End-User as described in Section 3.1.2.3 of the\nOpenID Connect Core protocol [OIDCC]. The OP returns an error\nresponse if the request is not valid or if any error is encountered.\n\n3.1.3.3. End-User Authorization\n\nAfter the End-User is authenticated, the OP MUST obtain authorization\ninformation from the End-User before releasing information to the\nRDAP Server/RP. This process is described in Section 3.1.2.4 of the\nOpenID Connect Core protocol [OIDCC].\n\n3.1.3.4. Authorization Response and Validation\n\nAfter the End-User is authenticated, the OP will send a response to\nthe RP that describes the result of the authorization process in the\nform of an Authorization Grant. The RP MUST validate the response.\nThis process is described in Sections 3.1.2.5 - 3.1.2.7 of the OpenID\nConnect Core protocol [OIDCC].\n\n3.1.3.5. Token Processing\n\nThe RP sends a Token Request using the Authorization Grant to a Token\nEndpoint to obtain a Token Response containing an Access Token, ID\nToken, and an OPTIONAL Refresh Token. The RP MUST validate the Token\nResponse. This process is described in Section 3.1.3 of the OpenID\nConnect Core protocol [OIDCC].\n\n3.1.3.6. Delivery of User Information\n\nThe set of claims can be retrieved by sending a request to a UserInfo\nEndpoint using the Access Token. The claims MAY be returned in the\nID Token. The process of retrieving claims from a UserInfo Endpoint\nis described in Section 5.3 of the OpenID Connect Core protocol\n[OIDCC].\nOpenID Connect specifies a set of standard claims in Section 5.1. Additional claims for RDAP are described in Section 3.1.4.\n\n3.1.4. Specialized Claims for RDAP\n\nOpenID Connect claims are pieces of information used to make assertions about an entity. Section 5 of the OpenID Connect Core protocol [OIDCC] describes a set of standard claims that can be used to identify a person. Section 5.1.2 notes that additional claims MAY be used, and it describes a method to create them. The set of claims that are specific to RDAP are associated with an OAuth scope request parameter value (see Section 3.3 of RFC 6749 ([RFC6749])) of \"rdap\".\n\n3.1.4.1. Stated Purposes\n\nThere are communities of RDAP users and operators who wish to make and validate claims about a user’s \"need to know\" when it comes to requesting access to a resource. For example, a law enforcement agent or a trademark attorney may wish to be able to assert that they have a legal right to access a protected resource, and a server operator will need to be able to receive and validate that claim. These needs can be met by defining and using an additional \"rdap_allowed_purposes\" claim.\n\nThe \"rdap_allowed_purposes\" claim identifies the purposes for which access to a protected resource can be requested by an End-User. Use of the \"rdap_allowed_purposes\" claim is OPTIONAL; processing of this claim is subject to server acceptance of the purposes, the trust level assigned to this claim by the server, and successful authentication of the End-User. Unrecognized purpose values MUST be ignored and the associated query MUST be processed as if the unrecognized purpose value was not present at all.\n\nThe \"rdap_allowed_purposes\" claim is represented as an array of case-sensitive StringOrURI values as specified in Section 2 of the JSON Web Token (JWT) specification ([RFC7519]). An example:\n\n\"rdap_allowed_purposes\": [\"domainNameControl\",\"dnsTransparency\"]\n\nIndividual purpose values are registered with IANA. Each entry in the registry contains the following fields:\n\nValue: the purpose string value being registered. Value strings can contain upper case characters from \"A\" to \"Z\", lower case ASCII characters from \"a\" to \"z\", and the underscore (\"_\") character. Value strings contain at least one character and no more than 64 characters.\nDescription: a one- or two-sentence description of the meaning of the purpose value, how it might be used, and/or how it should be interpreted by clients and servers.\n\nThis registry is operated under the \"Specification Required\" policy defined in RFC 5226 ([RFC5226]). The set of initial values used to populate the registry as described in Section 8.3 are taken from the final report (https://www.icann.org/en/system/files/files/final-report-06jun14-en.pdf) produced by the Expert Working Group on gTLD Directory Services chartered by the Internet Corporation for Assigned Names and Numbers (ICANN).\n\n3.1.4.2. Do Not Track\n\nThere are also communities of RDAP users and operators who wish to make and validate claims about a user’s wish to not have their queries logged, tracked, or recorded. For example, a law enforcement agent may wish to be able to assert that their queries are part of a criminal investigation and should not be tracked due to a risk of query exposure compromising the investigation, and a server operator will need to be able to receive and validate that claim. These needs can be met by defining and using an additional \"do not track\" claim.\n\nThe \"do not track\" (\"rdap_dnt_allowed\") claim can be used to identify an End-User that is authorized to perform queries without the End-User’s association with those queries being logged, tracked, or recorded by the server. Client use of the \"rdap_dnt_allowed\" claim is OPTIONAL. Server operators MUST NOT log, track, or record any association of the query and the End-User’s identity if the End-User is successfully identified and authorized, the \"rdap_dnt_allowed\" claim is present, the value of the claim is \"true\", and accepting the claim complies with local regulations regarding logging and tracking.\n\nThe \"rdap_dnt_allowed\" value is represented as a JSON boolean literal. An example:\n\n```\nrdap_dnt_allowed: true\n```\n\nNo special query tracking processing is required if this claim is not present or if the value of the claim is \"false\". Use of this claim MUST be limited to End-Users who are granted \"do not track\" privileges in accordance with service policies and regulations. Specification of these policies and regulations is beyond the scope of this document.\n4. Protocol Parameters\n\nThis specification adds the following protocol parameters to RDAP:\n\n1. Data structures to return information that describes an established session, the information needed to establish a session for a UI-constrained device, and the RDAP server’s OpenID Connect extension configuration.\n2. A query parameter to request authentication for a specific End-User identity.\n3. A query parameter to identify the purpose of the query.\n4. A query parameter to request that the server not log or otherwise record information about the identity associated with a query.\n5. Path segments to start, stop, refresh, and determine the status of an authenticated session for a specific End-User identity.\n\n4.1. Data Structures\n\nThis specification describes three new data structures that are used to return information to a client: a \"roidc1_session\" data structure that contains information that describes an established session, a \"roidc1_deviceInfo\" data structure that contains information that describes an active attempt to establish a session on a UI-constrained device, and a \"roidc1_openidcConfiguration\" data structure that describes the OpenID Connect configuration and related extension features supported by the RDAP server.\n\n4.1.1. Session\n\nThe \"roidc1_session\" data structure is an object that contains two sub-objects:\n\n1. A \"userClaims\" object that contains the set of claims associated with the End-User's identity as used/requested by the RDAP server to make access control decisions. The set of possible values is determined by OP policy.\n2. A \"sessionInfo\" object that contains two members:\n a. \"tokenExpiration\": an integer value that represents the number of seconds from the current time for which the Access Token remains valid, and\n b. \"tokenRefresh\": A boolean value that indicates if the OP supports refresh tokens. As described in RFC 6749 [RFC6749], support for refresh tokens is OPTIONAL.\n\nAn example of a \"roidc1_session\" data structure:\n\"roidc1_session\": {\n \"userClaims\": {\n \"sub\": \"103892603076825016132\",\n \"name\": \"User Person\",\n \"given_name\": \"User\",\n \"family_name\": \"Person\",\n \"picture\": \"https://lh3.example.com/a-/AOh14=s96-c\",\n \"email\": \"user@example.com\",\n \"email_verified\": true,\n \"locale\": \"en\",\n \"rdap_allowed_purposes\": [\n \"domainNameControl\",\n \"personalDataProtection\"\n ],\n \"rdap_dnt_allowed\": false\n },\n \"sessionInfo\": {\n \"tokenExpiration\": 3599,\n \"tokenRefresh\": true\n }\n}\n\nFigure 1\n\n4.1.2. Device Info\n\nThe flow described in Section 3.1.3 requires an End-User to interact with a server using a user interface that can process HTTP. This will not work well in situations where the client is automated or an End-User is using a command line user interface such as curl (http://curl.haxx.se/) or wget (https://www.gnu.org/software/wget/). This limitation can be addressed using a web browser on a second device. The information that needs to be entered using the web browser is contained in the \"roidc1_deviceInfo\" data structure.\n\nThe \"roidc1_deviceInfo\" data structure is an object that contains three members:\n\n1. \"verification_url\": the URL that the End-User needs to visit using the web browser,\n2. \"user_code\": the string value that the End-User needs to enter on the form presented in the web browser, and\n3. \"expires_in\": an integer value that represents the number of seconds after which the opportunity to visit the URL and enter the user_code will expire.\n\nAn example of a \"roidc1_deviceInfo\" data structure:\n\"roidc1_deviceInfo\": {\n \"verification_url\": \"https://www.example.com/device\",\n \"user_code\": \"NJJQ-GJFC\",\n \"expires_in\": \"1800\"\n}\n\nFigure 2\n\n4.1.3. OpenID Connect Configuration\n\nThe \"roidc1_openidcConfiguration\" data structure is an object with the following members:\n\n1. \"dntSupported\": (MANDATORY) a boolean value that describes RDAP server support for the \"roidc1_dnt\" query parameter (see Section 4.3.2).\n2. \"endUserIdentifierDiscoverySupported\": (OPTIONAL) a boolean value that describes RDAP server support for discovery of End-User identifiers. The default value is \"true\".\n3. \"issuerIdentifierSupported\": (OPTIONAL) a boolean value that describes RDAP server support for explicit client specification of an Issuer Identifier. The default value is \"true\".\n4. \"openidcProviders\": (OPTIONAL) a list of objects with the following members that describes the set of OPs that are supported by the RDAP server. This data is RECOMMENDED if the value of issuerIdentifierSupported is \"true\":\n a. \"iss\": (MANDATORY) a string value equal to Issuer Identifier of the OP as per OpenID Connect Core specification [OIDCC]\n b. \"name\": (MANDATORY) a string value representing the human-friendly name of the OP.\n c. \"default\": (OPTIONAL) a boolean value that describes RDAP server support for an OPTIONAL default OP that will be used when a client omits the \"roidc1_id\" and \"roidc1_iss\" query parameters from a \"roidc1_session/login\" request. Only one member of this set can be identified as the default OP by setting a value of \"true\". The default value is \"false\".\n\nAn example of a \"roidc1_openidcConfiguration\" data structure:\n\"roidc1_openidcConfiguration\": {\n \"dntSupported\": false,\n \"endUserIdentifierDiscoverySupported\": true,\n \"issuerIdentifierSupported\": true,\n \"openidcProviders\": [\n {\n \"iss\": \"https://idp.example.com\",\n \"name\": \"Example IDP\"\n },\n {\n \"iss\": \"https://accounts.example.net\",\n \"name\": \"Login with EXAMPLE\"\n },\n {\n \"iss\": \"https://auth.nic.example/auth/realms/rdap\",\n \"name\": \"Default OP for the Example RDAP server\",\n \"default\": \"true\"\n }\n ]\n}\n\nFigure 3\n\n4.2. Client Login\n\nClient authentication is requested by sending a \"roidc1_session/login\" request to an RDAP server. If the RDAP server supports only remote Authorization Servers, the \"roidc1_session/login\" request MUST include at least one of an End-User Identifier or an OP Issuer Identifier.\n\n4.2.1. End-User Identifier\n\nThe End-User identifier is delivered using one of two methods: by adding a query component to an RDAP request URI using the syntax described in Section 3.4 of RFC 3986 [RFC3986], or by including an HTTP authorization header for the Basic authentication scheme as described in RFC 7617 [RFC7617]. Clients can use either of these methods to deliver the End-User identifier to a server that supports remote Authorization Servers and End-User identifier discovery. Servers that support remote Authorization Servers and End-User identifier discovery MUST accept both methods. If the RDAP server supports a default Authorization Server or End-User identifier discovery is not supported, the End-User identifier MAY be omitted.\nThe query used to request client authentication is represented as an\nOPTIONAL \"key=value\" pair using a key value of \"roidc1_id\" and a\nvalue component that contains the client identifier issued by an OP.\nAn example for client identifier \"user.idp.example\":\n\nhttps://example.com/rdap/roidc1_session/\nlogin?roidc1_id=user.idp.example\n\nThe authorization header for the Basic authentication scheme contains\na Base64-encoded representation of the client identifier issued by an\nOP. No password is provided. An example for client identifier\n\"user.idp.example\":\n\nhttps://example.com/rdap/roidc1_session/login\nAuthorization: Basic dXNlci5pZHAuZXhhbXBsZQ==\n\nAn example for use with a default Authorization Server:\n\nhttps://example.com/rdap/roidc1_session/login\n\n4.2.2. OP Issuer Identifier\n\nThe OP’s Issuer Identifier is delivered by adding a query component\nto an RDAP request URI using the syntax described in Section 3.4 of\nRFC 3986 [RFC3986]. If the RDAP server supports a default\nAuthorization Server, the Issuer Identifier MAY be omitted.\n\nThe query used to request client authentication is represented as an\nOPTIONAL \"key=value\" pair using a key value of \"roidc1_iss\" and a\nvalue component that contains the Issuer Identifier associated with\nan OP. An RDAP server MAY accept Issuer Identifiers not specified in\nthe \"roidc1_openidcConfiguration\" data structure and MAY also decide\nto accept specific Issuer Identifiers only from specific clients.\n\nAn example for Issuer Identifier \"https://idp.example.com\":\n\nhttps://example.com/rdap/roidc1_session/\nlogin?roidc1_iss=https%3A%2F%2Fidp.example.com\n\n4.2.3. Login Response\n\nThe response to the login request MUST use the response structures\nspecified in RFC 9083 [RFC9083]. In addition, the response MUST\ninclude an indication of the requested operation’s success or failure\nin the \"notices\" data structure (including the client identifier),\nand, if successful, a \"roidc1_session\" data structure.\nAn example of a successful \"roidc1_session/login\" response:\n\n```json\n{\n \"rdapConformance\": [\n \"roidc1\"\n ],\n \"lang\": \"en-US\",\n \"notices\": {\n \"title\": \"Login Result\",\n \"description\": [\n \"Login succeeded\",\n \"user.idp.example\"\n ]\n },\n \"roidc1_session\": {\n \"userClaims\": {\n \"sub\": \"103892603076825016132\",\n \"name\": \"User Person\",\n \"given_name\": \"User\",\n \"family_name\": \"Person\",\n \"picture\": \"https://lh3.example.com/a/-/AOh14=s96-c\",\n \"email\": \"user@example.com\",\n \"email_verified\": true,\n \"locale\": \"en\",\n \"rdap_allowed_purposes\": [\n \"domainNameControl\",\n \"personalDataProtection\"\n ],\n \"rdap_dnt_allowed\": false\n },\n \"sessionInfo\": {\n \"tokenExpiration\": 3599,\n \"tokenRefresh\": true\n }\n }\n}\n```\n\nFigure 4\n\nAn example of a failed \"roidc1_session/login\" response:\n4.2.4. Clients with Limited User Interfaces\n\nThe \"OAuth 2.0 Device Authorization Grant\" [RFC8628] provides an OPTIONAL method to request user authorization from devices that have an Internet connection, but lack a suitable browser for a more traditional OAuth flow. This method requires an End-User to use a second device (such as a smart telephone) that has access to a web browser for entry of a code sequence that is presented on the UI-constrained device.\n\n4.2.4.1. UI-constrained Client Login\n\nClient authentication is requested by sending a \"roidc1_session/device\" request to an RDAP server. If the RDAP server supports only remote Authorization Servers, the \"roidc1_session/device\" request MUST include an End-User identifier that’s delivered using one of two methods: by adding a query component to an RDAP request URI using the syntax described in Section 3.4 of RFC 3986 [RFC3986], or by including an HTTP authorization header for the Basic authentication scheme as described in RFC 7617 [RFC7617]. If the RDAP server supports a default Authorization Server, the End-User identifier MAY be omitted. Clients can use either of these methods. Servers MUST support both methods.\n\nThe query used to request client authentication is represented as an OPTIONAL \"key=value\" pair using a key value of \"id\" and a value component that contains the client identifier issued by an OP.\n\nAn example using wget for client identifier \"user.idp.example\":\n\n wget -qO- --keep-session-cookies --save-cookies\\ \n https://example.com/rdap/session/device?roidc1_id=user.idp.example\nFigure 6\n\nThe authorization header for the Basic authentication scheme contains a Base64-encoded representation of the client identifier issued by an OP. No password is provided.\n\nAn example using curl and an authorization header:\n\n```\ncurl -H \"Authorization: Bearer dXNlci5pZHAuZXhhbXBsZQ==\"\\\n -c cookies.txt https://example.com/rdap/session/device\n```\n\nFigure 7\n\nThe response to this request MUST use the response structures specified in RFC 9083 [RFC9083]. In addition, the response MUST include an indication of the requested operation’s success or failure in the \"notices\" data structure (including the client identifier), and, if successful, a \"roidc1_deviceInfo\" data structure.\n\nAn example of a \"roidc1_session/device\" response:\n\n```\n{\n \"rdapConformance\": [\n \"roidc1\"\n ],\n \"lang\": \"en-US\",\n \"notices\": {\n \"title\": \"Device Login Result\",\n \"description\": [\n \"Login succeeded\",\n \"user.idp.example\"\n ]\n },\n \"roidc1_deviceInfo\": {\n \"verification_url\": \"https://www.example.com/device\",\n \"user_code\": \"NJJQ-GJFC\",\n \"expires_in\": 1800\n }\n}\n```\n\nFigure 8\n4.2.4.2. UI-constrained Client Login Polling\n\nAfter successful processing of the \"roidc1_session/device\" request, the client MUST send a \"roidc1_session/devicepoll\" request to the RDAP server to continue the login process. This request performs the polling function described in RFC 8628 [RFC8628], allowing the RDAP server to wait for the End-User to enter the information returned from the \"roidc1_session/device\" request using the interface on their second device. After the End-User has completed that process, or if the process fails or times out, the OP will respond to the polling requests with an indication of success or failure.\n\nAn example using wget:\n\n```\nwget -qO- --load-cookies cookies.txt\\https://example.com/rdap/roidc1_session/devicepoll\n```\n\nFigure 9\n\nAn example using curl:\n\n```\ncurl -b cookies.txt https://example.com/rdap/roidc1_session/devicepoll\n```\n\nFigure 10\n\nThe response to this request MUST use the response structures described in Section 4.2. RDAP query processing can continue normally on the UI-constrained device once the \"login\" process has been completed.\n\n4.3. RDAP Query Parameters\n\nThis specification describes two OPTIONAL query parameters for use with RDAP queries that request access to information associated with protected resources:\n\n1. \"roidcl_qp\": A query parameter to identify the purpose of the query.\n2. \"roidcl_dnt\": A query parameter to request that the server not log or otherwise record information about the identity associated with a query.\n\nOne or both of these parameters MAY be added to an RDAP request URI using the syntax described in Section 3.4 of RFC 3986 [RFC3986].\n4.3.1. RDAP Query Purpose\n\nThis query is represented as a \"key=value\" pair using a key value of \"roidc1_qp\" and a value component that contains a single query purpose string from the set of allowed purposes associated with the End-User’s identity (see Section 3.1.4.1). If present, the server SHOULD compare the value of the parameter to the \"rdap_allowed_purposes\" claim values associated with the End-User’s identity and ensure that the requested purpose is present in the set of allowed purposes. The RDAP server MAY choose to ignore both requested purpose and the \"rdap_allowed_purposes\" claim values if they are inconsistent with local server policy. The server MUST return an HTTP 403 (Forbidden) response if the requested purpose is not an allowed purpose. If this parameter is not present, the server MUST process the query and make an access control decision based on any other information known to the server about the End-User and the information they are requesting. For example, a server MAY treat the request as one performed by an unidentified or unauthenticated user and return either an error or an appropriate subset of the available data. An example domain query using the \"roidc1_qp\" query parameter:\n\nhttps://example.com/rdap/domain/example.com?roidc1_qp=legalActions\n\n4.3.2. RDAP Do Not Track\n\nThis query is represented as a \"key=value\" pair using a key value of \"roidc1_dnt\" and a value component that contains a single boolean value. A value of \"true\" indicates that the End-User is requesting that their query not be tracked or logged in accordance with server policy. A value of \"false\" indicates that the End-User is accepting that their query can be tracked or logged in accordance with server policy. The server MUST return an HTTP 501 (Not Implemented) response if the server is unable to perform the action requested by this query parameter. An example domain query using the \"roidc1_dnt\" query parameter:\n\nhttps://example.com/rdap/domain/example.com?roidc1_dnt=true\n\n4.4. Session Status\n\nClients MAY send a query to an RDAP server to determine the status of an existing login session using a \"roidc1_session/status\" path segment. An example \"roidc1_session/status\" request:\n\nhttps://example.com/rdap/roidc1_session/status\nThe response to this query MUST use the response structures specified in RFC 9083 [RFC9083]. In addition, the response MUST include an indication of the requested operation’s success or failure in the \"notices\" data structure (including the client identifier), and, if successful, a \"roidc1_session\" data structure.\n\nAn example of a \"roidc1_session/status\" response:\n\n```json\n{\n \"rdapConformance\": [\n \"roidc1\"\n ],\n \"lang\": \"en-US\",\n \"notices\": {\n \"title\": \"Session Status Result\",\n \"description\": [\n \"Session status succeeded\",\n \"user.idp.example\"\n ]\n },\n \"roidc1_session\": {\n \"userClaims\": {\n \"sub\": \"103892603076825016132\",\n \"name\": \"User Person\",\n \"given_name\": \"User\",\n \"family_name\": \"Person\",\n \"picture\": \"https://lh3.example.com/a-/AOh14=s96-c\",\n \"email\": \"user@example.com\",\n \"email_verified\": true,\n \"locale\": \"en\",\n \"rdap_allowed_purposes\": [\n \"domainNameControl\",\n \"personalDataProtection\"\n ],\n \"rdap_dnt_allowed\": false\n },\n \"sessionInfo\": {\n \"tokenExpiration\": 3490,\n \"tokenRefresh\": true\n }\n }\n}\n```\n\nFigure 11\n4.5. Session Refresh\n\nClients MAY send a request to an RDAP server to refresh, or extend, an existing login session using a \"roidc1_session/refresh\" path segment. The RDAP server MAY attempt to refresh the access token associated with the current session as part of extending the session for a period of time determined by the RDAP server. As described in RFC 6749 [RFC6749], OP support for refresh tokens is OPTIONAL. An RDAP server MUST determine if the OP supports token refresh and process the refresh request by either requesting refresh of the access token or by returning a response that indicates that token refresh is not supported by the OP in the \"notices\" data structure. An example \"roidc1_session/refresh\" request:\n\nhttps://example.com/rdap/roidc1_session/refresh\n\nThe response to this request MUST use the response structures specified in RFC 9083 [RFC9083]. In addition, the response MUST include an indication of the requested operation’s success or failure in the \"notices\" data structure (including the client identifier), and, if successful, a \"roidc1_session\" data structure.\n\nAn example of a \"roidc1_session/refresh\" response:\nClients MAY send a request to an RDAP server to terminate an existing login session. Termination of a session is requested using a \"roidc1_session/logout\" path segment. Access and refresh tokens can be revoked during the \"roidc1_session/logout\" process as described in RFC 7009 [RFC7009] if supported by the OP (token revocation endpoint support is OPTIONAL per RFC 8414 [RFC8414]). If supported, this feature SHOULD be used to ensure that the tokens are not mistakenly associated with a future RDAP session. Alternatively, an RDAP server\nMAY attempt to logout from the OP using the \"OpenID Connect RP-Initiated Logout\" protocol ([OIDCL]) if that protocol is supported by the OP.\n\nAn example \"roidc1_session/logout\" request:\n\nhttps://example.com/rdap/roidc1_session/logout\n\nThe response to this request MUST use the response structures specified in RFC 9083 [RFC9083]. In addition, the response MUST include an indication of the requested operation’s success or failure in the \"notices\" data structure (including the client identifier). The \"notices\" data structure MUST also include an indication of the success or failure of any attempt to logout from the OP or to revoke the tokens issued by the OP.\n\nAn example of a \"roidc1_session/logout\" response:\n\n```json\n{\n \"rdapConformance\": [\n \"roidc1\"\n ],\n \"lang\": \"en-US\",\n \"notices\": {\n \"title\": \"Logout Result\",\n \"description\": [\n \"Logout succeeded\",\n \"user.idp.example\",\n \"Provider logout failed: Not supported by provider.\"\n ],\n \"Token revocation successful.\"\n }\n}\n```\n\nFigure 13\n\nIn the absence of a \"logout\" request, an RDAP session MUST be terminated by the RDAP server after a server-defined period of time. The server should also take appropriate steps to ensure that the tokens associated with the terminated session cannot be reused. This SHOULD include revoking the tokens or logging out from the OP if either operation is supported by the OP.\n4.7. Parameter Processing\n\nUnrecognized query parameters MUST be ignored. An RDAP server that processes an authenticated query MUST determine if the End-User identification information is associated with an OP that is recognized and supported by the server. Servers MUST reject queries that include identification information that is not associated with a supported OP by returning an HTTP 501 (Not Implemented) response. An RDAP server that receives a query containing identification information associated with a recognized OP MUST perform the steps required to authenticate the user with the OP, process the query, and return an RDAP response that is appropriate for the End-User's level of authorization and access.\n\n5. Token Exchange\n\nID tokens include an audience parameter that contains the OAuth 2.0 client_id of the RP as an audience value. In some operational scenarios (such as a client that is providing a proxy service), an RP can receive tokens with an audience value that does not include the RP's client_id. These tokens might not be trusted by the RP, and the RP might refuse to accept the tokens. This situation can be remedied by having the RP exchange these tokens with the OP for a set of trusted tokens that reset the audience parameter. This token exchange protocol is described in RFC 8693 [RFC8693]. This issue is not visible to the RDAP client and should be managed by the OpenID implementation used by the RDAP server.\n\n6. RDAP Query Processing\n\nOnce an RDAP session is active, an RDAP server MUST determine if the End-User is authorized to perform any queries that are received during the duration of the session. This MAY include rejecting queries outright, and it MAY include omitting or otherwise redacting information that the End-User is not authorized to receive. Specific processing requirements are beyond the scope of this document. A client can end a session explicitly by sending a \"roidc1_session/logout\" request to the RDAP server. A session can also be ended implicitly by the server after a server-defined period of time. The status of a session can be determined at any time by sending a \"roidc1_session/status\" query to the RDAP server.\n\nAn RDAP server MUST maintain session state information for the duration of an active session. This is commonly done using HTTP cookies as described in RFC 6265 [RFC6265]. Doing so allows End-User to submit queries without having to explicitly identify and authenticate themselves for each and every query.\n7. RDAP Conformance\n\nRDAP responses that contain values described in this document MUST indicate conformance with this specification by including an rdapConformance ([RFC9083]) value of \"roidc1\" (RDAP OpenID Connect version 1). The information needed to register this value in the RDAP Extensions Registry is described in Section 8.1.\n\nExample rdapConformance structure with extension specified:\n\n```\n\"rdapConformance\" :\n[ \n \"rdap_level_0\",\n \"roidc1\"\n]\n```\n\nFigure 14\n\n8. IANA Considerations\n\n8.1. RDAP Extensions Registry\n\nIANA is requested to register the following value in the RDAP Extensions Registry:\n\n- Extension identifier: roidc1\n- Registry operator: Any\n- Published specification: This document.\n- Contact: IESG <iesg@ietf.org>\n- Intended usage: This extension describes version 1 of a federated authentication method for RDAP using OAuth 2.0 and OpenID Connect.\n\n8.2. JSON Web Token Claims Registry\n\nIANA is requested to register the following values in the JSON Web Token Claims Registry:\n\n- Claim Name: \"rdap_allowed_purposes\"\n- Claim Description: This claim describes the set of RDAP query purposes that are available to an identity that is presented for access to a protected RDAP resource.\n- Change Controller: IESG\n- Specification Document(s): Section 3.1.4.1 of this document.\n\n- Claim Name: \"rdap_dnt_allowed\"\nClaim Description: This claim contains a JSON boolean literal that\ndescribes a \"do not track\" request for server-side tracking,\nlogging, or recording of an identity that is presented for access\nto a protected RDAP resource.\nChange Controller: IESG\nSpecification Document(s): Section 3.1.4.2 of this document.\n\n8.3. RDAP Query Purpose Registry\n\nIANA is requested to create a new protocol registry to manage RDAP\nquery purpose values. This registry should be named \"Registration\nData Access Protocol (RDAP) Query Purpose Values\" and should appear\nunder the \"Registration Data Access Protocol (RDAP)\" section of\nIANA’s protocol registries. The information to be registered and the\nprocedures to be followed in populating the registry are described in\nSection 3.1.4.1.\n\nSection at http://www.iana.org/protocols: Registration Data Access\nProtocol (RDAP)\n\nName of registry: Registration Data Access Protocol (RDAP) Query\nPurpose Values\n\nRegistration Procedure: Specification Required\n\nReference: This document\n\nRequired information: See Section 3.1.4.1.\n\nReview process: \"Specification Required\" as described in RFC 5226\n[RFC5226].\n\nSize, format, and syntax of registry entries: See Section 3.1.4.1.\n\nInitial assignments and reservations:\n\n-----BEGIN FORM-----\n\nValue: domainNameControl\n\nDescription: Tasks within the scope of this purpose include\ncreating and managing and monitoring a registrant’s own domain\nname, including creating the domain name, updating information\nabout the domain name, transferring the domain name, renewing the\ndomain name, deleting the domain name, maintaining a domain name\nportfolio, and detecting fraudulent use of the Registrant’s own\ncontact information.\nValue: personalDataProtection\n\nDescription: Tasks within the scope of this purpose include identifying the accredited privacy/proxy provider associated with a domain name and reporting abuse, requesting reveal, or otherwise contacting the provider.\n\nValue: technicalIssueResolution\n\nDescription: Tasks within the scope of this purpose include (but are not limited to) working to resolve technical issues, including email delivery issues, DNS resolution failures, and website functional issues.\n\nValue: domainNameCertification\n\nDescription: Tasks within the scope of this purpose include a Certification Authority (CA) issuing an X.509 certificate to a subject identified by a domain name.\n\nValue: individualInternetUse\n\nDescription: Tasks within the scope of this purpose include identifying the organization using a domain name to instill consumer trust, or contacting that organization to raise a customer complaint to them or file a complaint about them.\n\nValue: businessDomainNamePurchaseOrSale\nDescription: Tasks within the scope of this purpose include making purchase queries about a domain name, acquiring a domain name from a registrant, and enabling due diligence research.\n\n-----END FORM-----\n\n-----BEGIN FORM-----\n\nValue: academicPublicInterestDNSRResearch\n\nDescription: Tasks within the scope of this purpose include academic public interest research studies about domain names published in the registration data service, including public information about the registrant and designated contacts, the domain name’s history and status, and domain names registered by a given registrant (reverse query).\n\n-----END FORM-----\n\n-----BEGIN FORM-----\n\nValue: legalActions\n\nDescription: Tasks within the scope of this purpose include investigating possible fraudulent use of a registrant’s name or address by other domain names, investigating possible trademark infringement, contacting a registrant/licensee’s legal representative prior to taking legal action and then taking a legal action if the concern is not satisfactorily addressed.\n\n-----END FORM-----\n\n-----BEGIN FORM-----\n\nValue: regulatoryAndContractEnforcement\n\nDescription: Tasks within the scope of this purpose include tax authority investigation of businesses with online presence, Uniform Dispute Resolution Policy (UDRP) investigation, contractual compliance investigation, and registration data escrow audits.\n\n-----END FORM-----\n\n-----BEGIN FORM-----\n\nValue: criminalInvestigationAndDNSAbuseMitigation\nDescription: Tasks within the scope of this purpose include reporting abuse to someone who can investigate and address that abuse, or contacting entities associated with a domain name during an offline criminal investigation.\n\n------END FORM------\n\n------BEGIN FORM------\n\nValue: dnsTransparency\n\nDescription: Tasks within the scope of this purpose involve querying the registration data made public by registrants to satisfy a wide variety of use cases around informing the general public.\n\n------END FORM------\n\n9. Implementation Status\n\nNOTE: Please remove this section and the reference to RFC 7942 prior to publication as an RFC.\n\nThis section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in RFC 7942 [RFC7942]. The description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist.\n\nAccording to RFC 7942, \"this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit\".\n\nVersion -09 of this specification introduced changes that are incompatible with earlier implementations. Implementations that are consistent with this specification will be added as they are identified.\n9.1. Editor Implementation\n\nLocation: https://procuratus.net/rdap/\nDescription: This implementation is a functionally-limited RDAP server that supports only the path segments described in this specification. It uses the \"jumbojett/OpenID-Connect-PHP\" library found on GitHub, which appears to no longer be under active development. The library was modified to add support for the device authorization grant. Session variable management is still a little buggy. Supported OPs include Google (Gmail) and Yahoo.\nLevel of Maturity: This is a \"proof of concept\" research implementation.\nCoverage: This implementation includes all of the features described in this specification.\nVersion compatibility: Version -11+ of this specification.\nContact Information: Scott Hollenbeck, shollenbeck@verisign.com\n\n9.2. Verisign Labs\n\nResponsible Organization: Verisign Labs\nLocation: https://rdap.verisignlabs.com/\nDescription: This implementation includes support for domain registry RDAP queries using live data from the .cc and .tv country code top-level domains and the .career generic top-level domain. Three access levels are provided based on the authenticated identity of the client:\n1. Unauthenticated: Limited information is returned in response to queries from unauthenticated clients.\n2. Basic: Clients who authenticate using a publicly available identity provider like Google Gmail or Microsoft Hotmail will receive all of the information available to an unauthenticated client plus additional registration metadata, but no personally identifiable information associated with entities.\n3. Advanced: Clients who authenticate using a more restrictive identity provider will receive all of the information available to a Basic client plus whatever information the server operator deems appropriate for a fully authorized client. Currently supported identity providers include those developed by Verisign Labs (https://testprovider.rdap.verisignlabs.com/) and CZ.NIC (https://www.mojeid.cz/).\nLevel of Maturity: This is a \"proof of concept\" research implementation.\nCoverage: This implementation includes all of the features described in this specification.\nVersion compatibility: Version -07 of this specification.\nContact Information: Scott Hollenbeck, shollenbeck@verisign.com\n9.3. Viagenie\n\nResponsible Organization: Viagenie\nLocation: https://auth.viagenie.ca\nDescription: This implementation is an OpenID identity provider enabling users and registries to connect to the federation. It also includes a barebone RDAP client and RDAP server in order to test the authentication framework. Various level of purposes are available for testing.\nLevel of Maturity: This is a \"proof of concept\" research implementation.\nCoverage: This implementation includes most features described in this specification as an identity provider.\nVersion compatibility: Version -07 of this specification.\nContact Information: Marc Blanchet, marc.blanchet@viagenie.ca\n\n10. Security Considerations\n\nSecurity considerations for RDAP can be found in RFC 7481 [RFC7481]. Security considerations for OpenID Connect Core [OIDCC] and OAuth 2.0 [RFC6749] can be found in their reference specifications. OpenID Connect defines optional mechanisms for robust signing and encryption that can be used to provide data integrity and data confidentiality services as needed.\n\n10.1. Authentication and Access Control\n\nHaving completed the client identification, authorization, and validation process, an RDAP server can make access control decisions based on a comparison of client-provided information and local policy. For example, a client who provides an email address (and nothing more) might be entitled to receive a subset of the information that would be available to a client who provides an email address, a full name, and a stated purpose. Development of these access control policies is beyond the scope of this document.\n\n11. Acknowledgments\n\nThe author would like to acknowledge the following individuals for their contributions to the development of this document: Marc Blanchet, Tom Harrison, Russ Housley, Jasdip Singh, Rhys Smith, Jaromir Talir, Rick Wilhelm, and Alessandro Vesely. In addition, the Verisign Registry Services Lab development team of Joseph Harvey, Andrew Kaizer, Sai Mogali, Anurag Saxena, Swapneel Sheth, Nitin Singh, and Zhao Zhao provided critical \"proof of concept\" implementation experience that helped demonstrate the validity of the concepts described in this document.\nPawel Kowalik and Mario Loffredo provided significant text contributions that led to welcome improvements in several sections of this document. Their contributions are greatly appreciated.\n\n12. References\n\n12.1. Normative References\n\n\n12.2. Informative References\n\n\nAppendix A. Change Log\n\n00: Initial working group version ported from draft-hollenbeck-regext-rdap-openid-10.\n01: Modified ID Token delivery approach to note proper use of an HTTP bearer authorization header.\n02: Modified token delivery approach (Access Token is the bearer token) to note proper use of an HTTP bearer authorization header, fixing the change made in -01.\n03: Updated OAuth 2.0 Device Authorization Grant description and reference due to publication of RFC 8628.\n04: Updated OAuth 2.0 token exchange description and reference due to publication of RFC 8693. Corrected the RDAP conformance identifier to be registered with IANA.\n05: Keepalive refresh.\n06: Keepalive refresh.\n07: Added \"login_hint\" description to Section 3.1.3.2. Added some text to Section 3.1.4.2 to note that \"do not track\" requires compliance with local regulations.\n08: Rework of token management processing in Sections 4 and 5.\n09: Updated RDAP specification references. Added text to describe\nboth default and remote Authorization Server processing. Removed\ntext that described passing of ID Tokens as query parameters.\n10: Updated Section 3.1.3.1. Replaced token processing queries with\n\"login\", \"session\", and \"logout\" queries.\n11: Replaced queries with \"session/*\" queries. Added description of\n\"rdap\" OAuth scope. Added implementation status information.\n12: Updated data structure descriptions. Updated Section 8. Minor\nformatting changes due to a move to xml2rfc-v3 markup.\n13: Added support for OP discovery via OP’s Issuer Identifier.\nModified the RDAP conformance text to use \"roidc1\", and added that\nvalue to extension path segments, data structures, and query\nparameters. Changed the \"purpose\" and \"dnt\" claims to\n\"rdap_allowed_purposes\" (making it an array) and\n\"rdap_dnt_allowed\". Added the \"roidc1_qp\" and \"roidc1_dnt\" query\nparameters. Changed the descriptions of \"local\" OPs to \"default\"\nOPs.\n\nAuthor’s Address\n\nScott Hollenbeck\nVerisign Labs\n12061 Bluemont Way\nReston, VA 20190\nUnited States of America\nEmail: shollenbeck@verisign.com\nURI: http://www.verisignlabs.com/\nRegistration Protocols Extensions\nM. Loffredo\nInternet-Draft\nM. Martinelli\nIntended status: Standards Track\nIIT-CNR/Registro.it\nExpires: 3 November 2022\n2 May 2022\n\nRegistration Data Access Protocol (RDAP) Reverse search capabilities\ndraft-ietf-regext-rdap-reverse-search-11\n\nAbstract\n\nThe Registration Data Access Protocol (RDAP) does not include query\ncapabilities for finding the list of domains related to a set of\nentities matching a given search pattern. In the RDAP context, an\nentity can be associated with any defined object class. Moreover,\nother relationships between object classes exist and might be used\nfor providing a reverse search capability. Therefore, a reverse\nsearch can be applied to other use cases than the classic domain-\nentity scenario. This document describes an RDAP extension that\nallow servers to provide a reverse search feature based on the\nrelationship defined in RDAP between an object class for search and\nany related object class. The reverse search based on the domain-\nentity relationship is treated as a particular case.\n\nStatus of This Memo\n\nThis Internet-Draft is submitted in full conformance with the\nprovisions of BCP 78 and BCP 79.\n\nInternet-Drafts are working documents of the Internet Engineering\nTask Force (IETF). Note that other groups may also distribute\nworking documents as Internet-Drafts. The list of current Internet-\nDrafts is at https://datatracker.ietf.org/drafts/current/.\n\nInternet-Drafts are draft documents valid for a maximum of six months\nand may be updated, replaced, or obsoleted by other documents at any\ntime. It is inappropriate to use Internet-Drafts as reference\nmaterial or to cite them other than as \"work in progress.\"\n\nThis Internet-Draft will expire on 3 November 2022.\n\nCopyright Notice\n\nCopyright (c) 2022 IETF Trust and the persons identified as the\ndocument authors. All rights reserved.\n1. Introduction\n\nReverse Whois is a service provided by many web applications that allows users to find domain names owned by an individual or a company starting from the owner's details, such as name and email. Even if it has been considered useful for some legal purposes (e.g. uncovering trademark infringements, detecting cybercrimes), its availability as a standardized Whois capability has been objected to for two main reasons, which now don’t seem to conflict with an RDAP implementation.\n\nThe first objection concerns the potential risks of privacy violation. However, the domain name community is considering a new generation of Registration Directory Services [ICANN-RDS1] [ICANN-RDS2] [ICANN-RA], which provide access to sensitive data under...\nsome permissible purposes and in accordance with appropriate policies for requestor accreditation, authentication and authorization. RDAP’s reliance on HTTP means that it can make use of common HTTP-based approaches to authentication and authorization, making it more useful than Whois [RFC3912] in the context of such directory services. Since RDAP consequently permits a reverse search implementation complying with privacy protection principles, this objection is not well-founded.\n\nThe other objection to the implementation of a reverse search capability has been connected with its impact on server processing. However, the core RDAP specifications already define search queries, with similar processing requirements, so the distinction on which this objection is based is not clear.\n\nReverse searches, such as finding the list of domain names associated with contacts or nameservers, may be useful to registrars as well. Usually, registries adopt out-of-band solutions to provide results to registrars asking for reverse searches on their domains. Possible reasons for such requests are:\n\n* the loss of synchronization between the registrar database and the registry database;\n* the need for such data to perform bulk EPP [RFC5730] updates (e.g. changing the contacts of a set of domains, etc.).\n\nCurrently, RDAP does not provide any means for a client to search for the collection of domains associated with an entity [RFC9082]. A query (lookup or search) on domains can return the array of entities related to a domain with different roles (registrant, registrar, administrative, technical, reseller, etc.), but the reverse operation is not allowed. Only reverse searches to find the collection of domains related to a nameserver (ldhName or ip) can be requested. Since an entity can be in relationship with any RDAP object [RFC9083], the availability of a reverse search as largely intended can be common to all the object classes allowed for search. Through a further step of generalization, the meaning of reverse search in the RDAP context can be extended to include any query for retrieving all the objects in relationship with another matching a given search pattern.\n\nThe protocol described in this specification aims to extend the RDAP query capabilities to enable reverse search based on the relationships defined in RDAP between an object class for search and a related object class. The reverse search based on the domain-entity relationship is treated as a particular case of such a generic query model.\n1.1. Conventions Used in This Document\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"NOT RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.\n\n2. RDAP Path Segment Specification\n\nA generic reverse search path is described by the syntax:\n\n{searchable-resource-type}/reverse_search_0/{related-resource-type}?<search-condition>\n\nThe path segments are defined as in the following:\n\n* searchable-resource-type: it MUST be one of the resource types for search defined in Section 3.2 of [RFC9082] (i.e. \"domains\", \"nameservers\" and \"entities\") or a resource type extension;\n* related-resource-type: it MUST be one of the resource types for lookup defined in Section 3.1 of [RFC9082] (i.e. \"domain\", \"nameserver\", \"entity\", \"ip\" and \"autnum\") or a resource type extension;\n* search-condition: a sequence of \"property=search pattern\" predicates separated by the ampersand character (‘&’, US-ASCII value 0x0026). Each \"property\" represents a JSON object property of the RDAP object class corresponding to \"related-resource-type\". Objects are only included in the search results if they satisfy all included predicates. This includes predicates that are for the same property: it is necessary in such a case for the related object to match against each of those predicates. Based on their policy, servers MAY restrict the usage of predicates to make a valid search condition, by returning a 400 (Bad Request) response when a problematic request is received.\n\nWhile related-resource-type is defined as having one of a number of different values, the only searches defined in this document are for a related-resource-type of \"entity\". Searches for the other resource types specified in [RFC9082] and resource type extensions may be defined by future documents.\n\nPartial string matching in search patterns is allowed as defined in section 4.1 of [RFC9082].\n3. RDAP Response Specification\n\nReverse search responses use the formats defined in section 8 of [RFC9083], which correspond to the searchable resource types defined in Section 2.\n\n4. Reverse Searches Based on Entity Details\n\nSince in RDAP, an entity can be associated with any other object class, the most common kind of reverse search is one based on an entity’s details. Such reverse searches arise from the query model by setting the related resource type to \"entity\".\n\nBy selecting a specific searchable resource type, the resulting reverse search aims at retrieving all the objects (e.g. all the domains) that are related to any entity object matching the search conditions.\n\nThis section defines the following reverse search properties servers SHOULD support regardless of the searchable resource type being selected:\n\n- **Reverse search property: role**\n - RDAP property: $..entities[*].roles\n - Reference: Section 10.2.4 of [RFC9083]\n\n- **Reverse search property: handle**\n - RDAP property: $..entities[*].handle\n - Reference: Section 5.1 of [RFC9083]\n\n- **Reverse search property: fn**\n - RDAP property: $..entities[*].vcardArray[1][?(@[0]=='fn')][3]\n - Reference: Section 6.2.1 of [RFC6350]\n\n- **Reverse search property: email**\n - RDAP property: $..entities[*].vcardArray[1][?(@[0]=='email')][3]\n - Reference: Section 6.4.2 of [RFC6350]\n\nThe mapping between the reverse search property and the corresponding RDAP response property is done through the use of a JSONPath expression [I-D.ietf-jsonpath-base].\n\nThe presence of a predicate on the reverse search property \"role\" means that the RDAP response property \"roles\" must contain at least the specified role.\nThe last two properties are related to jCard elements [RFC7095], but the field references are to vCard [RFC6350], since jCard is the JSON format for vCard.\n\nExamples of reverse search paths based on the domain-entity relationship are presented in Figure 1.\n\n```\n/domains/reverse_search_0/entity?handle=CID-40*&role=technical\n```\n\n```\n/domains/reverse_search_0/entity?fn=Bobby*&role=registrant\n```\n\n```\n/domains/reverse_search_0/entity?handle=RegistrarX&role=registrar\n```\n\nFigure 1\n\nDocuments that deprecate or restructure RDAP responses such that one or more of the properties listed above becomes invalid MUST either note that the relevant reverse search is no longer available (in the case of deprecation) or describe how to continue supporting the relevant search by way of some new RDAP property (in the case of restructuring).\n\nA server that includes additional fields in its objects in accordance with the extensibility provisions of section 6 of [RFC7480] MAY support the use of those fields in search conditions, in the same way as for the search conditions defined in this section. Support for such fields in the reverse search context MUST be documented in the extension specification.\n\n5. RDAP Conformance\n\nServers complying with this specification MUST include the value \"reverse_search_0\" in the rdapConformance property of the help response [RFC9083]. The information needed to register this value in the \"RDAP Extensions\" registry is described in Section 8.\n\n6. Implementation Considerations\n\nTo limit the impact of processing the search predicates, servers are RECOMMENDED to make use of indexes and similar functionality in their underlying data store. In addition, risks with respect to performance degradation or result set generation can be mitigated by adopting practices used for standard searches, e.g. restricting the search functionality, limiting the rate of search requests according to the user’s authorization, truncating and paging the results, and returning partial responses.\n7. Implementation Status\n\nNOTE: Please remove this section and the reference to RFC 7942 prior to publication as an RFC.\n\nThis section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in [RFC7942]. The description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist.\n\nAccording to RFC 7942, \"this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit\".\n\n7.1. IIT-CNR/Registro.it RDAP Server\n\n* Responsible Organization: Institute of Informatics and Telematics of National Research Council (IIT-CNR)/Registro.it\n* Location: https://rdap.pubtest.nic.it/\n* Description: This implementation includes support for RDAP queries using data from the public test environment of .it ccTLD. Reverse search is allowed to authenticated users. Registrar users are allowed to perform reverse searches on their own domains and contacts. This is achieved by adding an implicit predicate to the search condition.\n* Level of Maturity: This is an \"alpha\" test implementation.\n* Coverage: This implementation includes all of the features described in this specification.\n* Contact Information: Mario Loffredo, mario.loffredo@iit.cnr.it\n\n7.2. IIT-CNR/Registro.it RDAP Client\n\n* Responsible Organization: Institute of Informatics and Telematics of National Research Council (IIT-CNR)/Registro.it\n* Location: https://web-rdap.pubtest.nic.it/\n* Description: This is a Javascript web-based RDAP client. RDAP responses are retrieved from RDAP servers by the browser, parsed into an HTML representation, and displayed in a format improving the user experience. Reverse search is allowed to authenticated users.\n* Level of Maturity: This is an \"alpha\" test implementation.\n* Coverage: This implementation includes all of the features described in this specification.\n* Contact Information: Francesco Donini, francesco.donini@iit.cnr.it\n\n8. IANA Considerations\n\nIANA is requested to register the following value in the RDAP Extensions Registry:\n\n* Extension identifier: reverse_search_0\n* Registry operator: Any\n* Published specification: This document.\n* Contact: IETF <iesg@ietf.org>\n* Intended usage: This extension describes reverse search query patterns for RDAP.\n\n9. Privacy Considerations\n\nThe search functionality defined in this document may affect the privacy of entities in the registry (and elsewhere) in various ways: see [RFC6973] for a general treatment of privacy in protocol specifications. Registry operators should be aware of the tradeoffs that result from implementation of this functionality.\n\nMany jurisdictions have laws or regulations that restrict the use of \"Personal Data\", per the definition in [RFC6973]. Given that, registry operators should ascertain whether the regulatory environment in which they operate permits implementation of the functionality defined in this document.\n\nIn general, given the sensitivity of this functionality, it SHOULD be accessible to authorized users only, and for specific use cases only.\n\nSince reverse search requests and responses could contain Personally Identifiable Information (PII), reverse search functionality SHOULD be available over HTTPS only.\n\nProviding reverse search in RDAP carries the following threats as described in [RFC6973]:\n\n* Correlation\n* Disclosure\n* Misuse of information\n\nTherefore, RDAP providers are REQUIRED to mitigate the risk of those threats by implementing appropriate measures supported by security services (see Section 10).\n\n10. Security Considerations\n\nSecurity services required to provide controlled access to the operations specified in this document are described in [RFC7481]. A non-exhaustive list of access control paradigms an RDAP provider can implement is presented in Appendix A.\n\nThe specification of the relationship within the reverse search path allows the RDAP servers to implement different authorization policies on a per-relationship basis.\n\n11. Acknowledgements\n\nThe authors would like to acknowledge the following individuals for their contributions to this document: Francesco Donini, Scott Hollenbeck, Francisco Arias, Gustavo Lozano, Eduardo Alvarez, Ulrich Wisser and James Gould.\n\nTom Harrison and Jasdip Singh provided relevant feedback and constant support to the implementation of this proposal. Their contributions have been greatly appreciated.\n\n12. References\n\n12.1. Normative References\n\n\n12.2. Informative References\n\n[I-D.ietf-jsonpath-base]\nGössner, S., Normington, G., and C. Bormann, \"JSONPath: Query expressions for JSON\", Work in Progress, Internet-\nAppendix A. Paradigms to Enforce Access Control on Reverse Search in RDAP\n\nAccess control can be implemented according to different paradigms introducing increasingly stringent rules. The paradigms reported here in the following leverage the capabilities either supported natively or provided as extensions by the OpenID Connect [OIDCC]:\n\n* Role-Based Access Control: access rights are granted depending on roles. Generally, this is done by grouping users into fixed categories and assigning static grants to each category. A more dynamic approach can be implemented by using the OpenID Connect \"scope\" claim;\n* Purpose-Based Access Control: access rules are based on the notion of purpose, being the intended use of some data by a user. It can be implemented by tagging a request with the usage purpose and\nmaking the RDAP server check the compliance between the given purpose and the control rules applied to the data to be returned. The purpose can be stated within an out-of-band process by setting the OpenID Connect RDAP-specific \"purpose\" claim as defined in [I-D.ietf-regext-rdap-openid];\n\n* Attribute-Based Access Control: rules to manage access rights are evaluated and applied according to specific attributes describing the context within which data are requested. It can be implemented by setting within an out-of-band process additional OpenID Connect claims describing the request context and making the RDAP server check the compliance between the given context and the control rules applied to the data to be returned;\n\n* Time-Based Access Control: data access is allowed for a limited time only. It can be implemented by assigning the users with temporary credentials linked to access grants whose scope is limited.\n\nAppendix B. Change Log\n\n00: Initial working group version ported from draft-loffredo-regext-rdap-reverse-search-04\n01: Updated \"Privacy Considerations\" section.\n02: Revised the text.\n03: Refactored the query model.\n04: Keepalive refresh.\n05: Reorganized \"Abstract\". Corrected \"Conventions Used in This Document\" section. Added \"RDAP Conformance\" section. Changed \"IANA Considerations\" section. Added references to RFC7095 and RFC8174. Other minor edits.\n06: Updated \"Privacy Considerations\", \"Security Considerations\" and \"Acknowledgements\" sections. Added some normative and informative references. Added Appendix A.\n07: Updated normative references.\n08: Changed \"Implementation Status\" section. Updated informative references.\n09: Extended the query model to represent a reverse search based on any relationship between the RDAP object classes. Changed the path segment \"role\" into a query parameter.\n10: Updated \"Reverse Searches Based on Entity Details\" section to consider the use of JSContact format instead of jCard. Added references to JSContact documents.\n11: Updated the document based on Tom Harrison and James Gould feedback:\n * Updated section \"RDAP Path Segment Specification\":\n - Clarified how servers must evaluate a reverse search including predicates that are for the same property.\n- Specified the error response servers must return when receiving a wrong reverse search request according to their policy.\n- Clarified that searches for the related-resource-type values other than \"entity\" may be defined in future documents.\n* Reviewed text in section \"Reverse Searches Based on Entity Details\" about reverse searches based on custom response extensions.\n* Removed references to JSContact documents in section \"Reverse Searches Based on Entity Details\". Moved the mapping between jCard properties used in the RDAP response and JSContact counterparts to draft-ietf-regext-rdap-jscontact.\n* Added section \"RDAP Response Specification\".\n* Changed the text to present reverse search as a single extension with multiple features.\n* Changed the definition of searchable-resource-type and related-resource-type to consider also the resource type extensions.\n* Replaced \"reverse\" with \"reverse_search_0\" in the generic reverse search path. Updated Figure 1 accordingly.\n* Removed the phrase \"but with a special focus on its privacy implications\" from both the \"Abstract\" and the \"Introduction\". Moved the mapping between jCard properties used in the RDAP response and JSContact counterparts to draft-ietf-regext-rdap-jscontact.\n* Reviewed the text of \"Privacy Considerations\" section.\n* Text cleaning.\n\nAuthors’ Addresses\n\nMario Loffredo\nIIT-CNR/Registro.it\nVia Moruzzi,1\n56124 Pisa\nItaly\nEmail: mario.loffredo@iit.cnr.it\nURI: http://www.iit.cnr.it\n\nMaurizio Martinelli\nIIT-CNR/Registro.it\nVia Moruzzi,1\n56124 Pisa\nItaly\nEmail: maurizio.martinelli@iit.cnr.it\nURI: http://www.iit.cnr.it\nFinding the Authoritative Registration Data (RDAP) Service\ndraft-ietf-regext-rfc7484bis-06\n\nAbstract\n\nThis document specifies a method to find which Registration Data Access Protocol (RDAP) server is authoritative to answer queries for a requested scope, such as domain names, IP addresses, or Autonomous System numbers. This document obsoletes RFC7484.\n\nStatus of This Memo\n\nThis Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.\n\nInternet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.\n\nInternet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as \"work in progress.\"\n\nThis Internet-Draft will expire on 1 August 2022.\n\nCopyright Notice\n\nCopyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved.\n\nThis document is subject to BCP 78 and the IETF Trust’s Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.\n1. Introduction\n\nQuerying and retrieving registration data from registries are defined in Registration Data Access Protocol (RDAP) [RFC7480] [RFC7481] [RFC9082] [RFC9083]. These documents do not specify where to send the queries. This document specifies a method to find which server is authoritative to answer queries for the requested scope.\nTop-Level Domains (TLDs), Autonomous System (AS) numbers, and network blocks are delegated by IANA to Internet registries such as TLD registries and Regional Internet Registries (RIRs) that then issue further delegations and maintain information about them. Thus, the bootstrap information needed by RDAP clients is best generated from data and processes already maintained by IANA; the relevant registries already exist at [ipv4reg], [ipv6reg], [asreg], and [domainreg]. This document obsoletes [RFC7484].\n\nPer this document, IANA has created new registries based on a JSON format specified in this document, herein named RDAP Bootstrap Service Registries. These new registries are based on the existing entries of the above-mentioned registries. An RDAP client fetches the RDAP Bootstrap Service Registries, extracts the data, and then performs a match with the query data to find the authoritative registration data server and appropriate query base URL.\n\n2. Conventions Used in This Document\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"NOT RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.\n\n3. Structure of the RDAP Bootstrap Service Registries\n\nThe RDAP Bootstrap Service Registries, as specified in Section 13 below, have been made available as JSON [RFC8259] objects, which can be retrieved via HTTP from locations specified by IANA. The JSON object for each registry contains a series of members containing metadata about the registry such as a version identifier, a timestamp of the publication date of the registry, and a description. Additionally, a \"services\" member contains the registry items themselves, as an array. Each item of the array contains a second-level array, with two elements, each of them being a third-level array.\n\nEach element of the Services Array is a second-level array with two elements: in order, an Entry Array and a Service URL Array.\n\nThe Entry Array contains all entries that have the same set of base RDAP URLs. The Service URL Array contains the list of base RDAP URLs usable for the entries found in the Entry Array. Elements within these two arrays are not ordered in any way.\n\nAn example structure of the JSON output of a RDAP Bootstrap Service Registry is illustrated:\nThe formal syntax is described in Section 10.\n\nThe \"version\" corresponds to the format version of the registry. This specification defines version \"1.0\".\n\nThe syntax of the \"publication\" value conforms to the Internet date/time format [RFC3339]. The value is the latest update date of the registry by IANA.\n\nThe optional \"description\" string can contain a comment regarding the content of the bootstrap object.\n\nPer [RFC7258], in each array of base RDAP URLs, the secure versions of the transport protocol SHOULD be preferred and tried first. For example, if the base RDAP URLs array contains both HTTPS and HTTP URLs, the bootstrap client SHOULD try the HTTPS version first.\n\nBase RDAP URLs MUST have a trailing \"/\" character because they are concatenated to the various segments defined in [RFC9082].\n\nJSON names MUST follow the format recommendations of section 6 of [RFC7480]. Any unrecognized JSON object properties or values MUST be ignored by implementations.\n\nInternationalized Domain Name labels used as entries or base RDAP URLs in the registries defined in this document MUST be only represented using their A-label form as defined in [RFC5890].\nAll Domain Name labels used as entries or base RDAP URLs in the registries defined in this document MUST be only represented in lowercase.\n\n4. Bootstrap Service Registry for Domain Name Space\n\nThe JSON output of this registry contains domain label entries attached to the root, grouped by base RDAP URLs, as shown in this example.\n\n```\n{\n \"version\": \"1.0\",\n \"publication\": \"2024-01-07T10:11:12Z\",\n \"description\": \"Some text\",\n \"services\": [\n [\n [\"net\", \"com\"],\n [\"https://registry.example.com/myrdap/\"\n ],\n [\n [\"org\", \"mytld\"],\n [\"https://example.org/\"\n ],\n [\n [\"xn--zckzah\"],\n [\"https://example.net/rdap/xn--zckzah/\",\n \"http://example.net/rdap/xn--zckzah/\n ]\n ]\n}\n```\n\nThe domain name’s authoritative registration data service is found by doing the label-wise longest match of the target domain name with the domain values in the Entry Arrays in the IANA Bootstrap Service Registry for Domain Name Space. The match is done per label, from right to left. If the longest match results in multiple entries, then those entries are considered equivalent. The values contained in the Service URL Array of the matching second-level array are the valid base RDAP URLs as described in [RFC9082].\nFor example, a domain RDAP query for a.b.example.com matches the com entry in one of the arrays of the registry. The base RDAP URL for this query is then taken from the second element of the array, which is an array of base RDAP URLs valid for this entry. The client chooses one of the base URLs from this array; in this example, it chooses the only one available, \"https://registry.example.com/myrdap/\". The segment specified in [RFC9082] is then appended to the base URL to complete the query. The complete query is then \"https://registry.example.com/myrdap/domain/a.b.example.com\".\n\nIf a domain RDAP query for a.b.example.com matches both com and example.com entries in the registry, then the longest match applies and the example.com entry is used by the client.\n\nIf the registry contains entries such as com and goodexample.com, then a domain RDAP query for example.com only matches the com entry because matching is done on a per-label basis.\n\nThe entry for the root of the domain name space is specified as \"\".\n\n5. Bootstrap Service Registries for Internet Numbers\n\nThis section discusses IPv4 and IPv6 address space and Autonomous System numbers.\n\nFor IP address space, the authoritative registration data service is found by doing a longest match of the target address with the values of the arrays in the corresponding RDAP Bootstrap Service Registry for Address Space. The longest match is done the same way as in packet forwarding: the addresses are converted in binary form and then the binary strings are compared to find the longest match up to the specified prefix length. The values contained in the second element of the array are the base RDAP URLs as described in [RFC9082]. The longest match method enables covering prefixes of a larger address space pointing to one base RDAP URL while more specific prefixes within the covering prefix are being served by another base RDAP URL.\n\n5.1. Bootstrap Service Registry for IPv4 Address Space\n\nThe JSON output of this registry contains IPv4 prefix entries, specified in Classless Inter-domain Routing (CIDR) format [RFC4632] and grouped by RDAP URLs, as shown in this example.\n\n\n```\n{\n \"version\": \"1.0\",\n \"publication\": \"2024-01-07T10:11:12Z\",\n \"description\": \"RDAP Bootstrap file for example registries.\",\n \"services\": [\n [\n [\"198.51.100.0/24\", \"192.0.0.0/8\"],\n [\"https://rir1.example.com/myrdap/\"]\n ],\n [\n [\"203.0.113.0/24\", \"192.0.2.0/24\"],\n [\"https://example.org/\"]\n ],\n [\n [\"203.0.113.0/28\"],\n [\"https://example.net/rdaprir2/\",\n \"http://example.net/rdaprir2/\"]\n ]\n ]\n}\n```\n\nFor example, a query for \"192.0.2.1/25\" matches the \"192.0.0.0/8\" entry and the \"192.0.2.0/24\" entry in the example registry above. The latter is chosen by the client because it is the longest match. The base RDAP URL for this query is then taken from the second element of the array, which is an array of base RDAP URLs valid for this entry. The client chooses one of the base URLs from this array; in this example, it chooses the only one available, \"https://example.org/\". The {resource} specified in [RFC9082] is then appended to the base URL to complete the query. The complete query is then \"https://example.org/ip/192.0.2.1/25\".\n\n5.2. Bootstrap Service Registry for IPv6 Address Space\n\nThe JSON output of this registry contains IPv6 prefix entries, using [RFC5952] text representation of the address prefixes format, grouped by base RDAP URLs, as shown in this example.\nFor example, a query for \"2001:db8:1000::/48\" matches the \"2001:db8::/34\" entry and the \"2001:db8:1000::/36\" entry in the example registry above. The latter is chosen by the client because it is the longest match. The base RDAP URL for this query is then taken from the second element of the array, which is an array of base RDAP URLs valid for this entry. The client chooses one of the base URLs from this array; in this example, it chooses \"https://example.net/rdapr2/\" because it’s the secure version of the protocol. The segment specified in [RFC9082] is then appended to the base URL to complete the query. The complete query is, therefore, \"https://example.net/rdapr2/ip/2001:db8:1000::/48\". If the target RDAP server does not answer, the client can then use another URL prefix from the array.\n5.3. Bootstrap Service Registry for AS Number Space\n\nThe JSON output of this registry contains Autonomous Systems number ranges entries, grouped by base RDAP URLs, as shown in this example. The Entry Array is an array containing the list of AS number ranges served by the base RDAP URLs found in the second element. Each element of the array contains two AS numbers represented in decimal format, separated by a hyphen, that represents the range of AS numbers between the two AS numbers (inclusive), where values are in increasing order (e.g. 100-200, not 200-100). A single AS number is represented as a range of two identical AS numbers. AS numbers are represented as ‘asplain’ as defined in [RFC5396]. Ranges MUST NOT overlap.\n\n```\n{\n \"version\": \"1.0\",\n \"publication\": \"2024-01-07T10:11:12Z\",\n \"description\": \"RDAP Bootstrap file for example registries.\",\n \"services\": [\n [\n \"64496-64496\",\n \"https://rir3.example.com/myrdap/\n ],\n [\n \"64497-64510\", \"65536-65551\"],\n \"https://example.org/\n ],\n [\n \"64512-65534\",\n \"http://example.net/rdaprir2/\",\n \"https://example.net/rdaprir2/\n ]\n ]\n}\n```\n\nFor example, a query for AS 65411 matches the 64512-65534 entry in the example registry above. The base RDAP URL for this query is then taken from the second element of the array, which is an array of base RDAP URLs valid for this entry. The client chooses one of the base URLs from this array; in this example, it chooses \"https://example.net/rdaprir2/\". The segment specified in [RFC9082] is then appended to the base URL to complete the query. The complete\nquery is, therefore, \"https://example.net/rdaprir2/autnum/65411\". If the server does not answer, the client can then use another URL prefix from the array.\n\n6. Entity\n\nEntities (such as contacts, registrants, or registrars) can be queried by handle as described in [RFC9082]. Since there is no global namespace for entities, this document does not describe how to find the authoritative RDAP server for entities. However, it is possible that, if the entity identifier was received from a previous query, the same RDAP server could be queried for that entity, or the entity identifier itself is a fully qualified URL that can be queried. The mechanism described in [RFC8521] MAY also be used.\n\n7. Non-existent Entries or RDAP URL Values\n\nThe registries may not contain the requested value. In these cases, there is no known RDAP server for that requested value, and the client SHOULD provide an appropriate error message to the user.\n\n8. Deployment and Implementation Considerations\n\nThis method relies on the fact that RDAP clients are fetching the IANA registries to then find the servers locally. Clients SHOULD NOT fetch the registry on every RDAP request. Clients SHOULD cache the registry, but use underlying protocol signaling, such as the HTTP Expires header field [RFC7234], to identify when it is time to refresh the cached registry.\n\nSome authorities of registration data may work together on sharing their information for a common service, including mutual redirection [REDIRECT-RDAP].\n\nWhen a new object is allocated, such as a new AS range, a new TLD, or a new IP address range, there is no guarantee that this new object will have an entry in the corresponding bootstrap RDAP registry, since the setup of the RDAP server for this new entry may become live and registered later. Therefore, the clients should expect that even if an object, such as TLD, IP address range, or AS range is allocated, the existence of the entry in the corresponding bootstrap registry is not guaranteed.\n9. Limitations\n\nThis method does not provide a direct way to find authoritative RDAP servers for any other objects than the ones described in this document. In particular, the following objects are not bootstrapped with the method described in this document:\n\n* entities\n\n* queries using search patterns that do not contain a terminating string that matches some entries in the registries\n\n* nameservers\n\n* help\n\n10. Formal Definition\n\nThis section is the formal definition of the registries. The structure of JSON objects and arrays using a set of primitive elements is defined in [RFC8259]. Those elements are used to describe the JSON structure of the registries.\n\n10.1. Imported JSON Terms\n\n* OBJECT: a JSON object, defined in Section 4 of [RFC8259]\n\n* MEMBER: a member of a JSON object, defined in Section 4 of [RFC8259]\n\n* MEMBER-NAME: the name of a MEMBER, defined as a \"string\" in Section 4 of [RFC8259]\n\n* MEMBER-VALUE: the value of a MEMBER, defined as a \"value\" in Section 4 of [RFC8259]\n\n* ARRAY: an array, defined in Section 5 of [RFC8259]\n\n* ARRAY-VALUE: an element of an ARRAY, defined in Section 5 of [RFC8259]\n\n* STRING: a \"string\", as defined in Section 7 of [RFC8259]\n\n10.2. Registry Syntax\n\nUsing the above terms for the JSON structures, the syntax of a registry is defined as follows:\n* **rdap-bootstrap-registry**: an OBJECT containing a MEMBER version and a MEMBER publication, an optional MEMBER description, and a MEMBER services-list\n\n* **version**: a MEMBER with MEMBER-NAME \"version\" and MEMBER-VALUE a STRING\n\n* **publication**: a MEMBER with MEMBER-NAME \"publication\" and MEMBER-VALUE a STRING\n\n* **description**: a MEMBER with MEMBER-NAME \"description\" and MEMBER-VALUE a STRING\n\n* **services-list**: a MEMBER with MEMBER-NAME \"services\" and MEMBER-VALUE a services-array\n\n* **services-array**: an ARRAY, where each ARRAY-VALUE is a service\n\n* **service**: an ARRAY of 2 elements, where the first ARRAY-VALUE is an entry-list and the second ARRAY-VALUE is a service-uri-list\n\n* **entry-list**: an ARRAY, where each ARRAY-VALUE is an entry\n\n* **entry**: a STRING\n\n* **service-uri-list**: an ARRAY, where each ARRAY-VALUE is a service-uri\n\n* **service-uri**: a STRING\n\n11. Security Considerations\n\nBy providing a bootstrap method to find RDAP servers, this document helps to ensure that the end users will get the RDAP data from an authoritative source, instead of from rogue sources. The method has the same security properties as the RDAP protocols themselves. The transport used to access the registries uses TLS [RFC8446].\n\nAdditional considerations on using RDAP are described in [RFC7481].\n\n12. Implementation Status\n\nNOTE: Please remove this section and the reference to RFC 7942 prior to publication as an RFC.\n\nThis section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in [RFC7942].\nThe description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist.\n\nAccording to [RFC7942], \"this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit\".\n\n12.1. RDAP Browser Mobile Application\n\nResponsible Organization: Viagenie\n\nAuthor: Marc Blanchet\n\nLocation: https://viagenie.ca/rdapbrowser/\n\nDescription: RDAP Browser is an RDAP client for domain names, IP addresses and AS numbers fetching the IANA registries described in this document to find the right authoritative RDAP server. End user can query any domain name, IP address or AS number and the registration data will be shown on the screen.\n\nLevel of Maturity: Production (i.e. in the Android and iOS App stores since August 2019)\n\nContact Information: rdapbrowser@viagenie.ca\n\nInformation last updated: March 2021\n\n12.2. ICANN Lookup Web Application\n\nResponsible Organization: ICANN\n\nLocation: https://lookup.icann.org\nDescription: ICANN’s Domain Name Registration Data Lookup is an RDAP client for domain names fetching the IANA registries described in this document to find the right authoritative RDAP server. End user can query any domain name and the registration data will be shown on the screen.\n\nLevel of Maturity: Production\n\nInformation last updated: March 2021\n\n12.3. ARIN Implementation\n\nResponsible Organization: ARIN\n\nBase URL: https://rdap-bootstrap.arin.net/bootstrap (Sample query: https://rdap-bootstrap.arin.net/bootstrap/autnum/1)\n\nDescription: ARIN RDAP Bootstrap server aids clients by reading the bootstrapping information published by IANA and using it to send HTTP redirects to RDAP queries. RDAP clients https://search.arin.net/ and NicInfo (https://github.com/arineng/nicinfo) use this bootstrap service. The underlying server software is open-sourced at https://github.com/arineng/rdap_bootstrap_server.\n\nLevel of Maturity: Production\n\nContact Information: info@arin.net\n\nInformation Last Updated: Nov 2020\n\n13. IANA Considerations\n\nIANA has created the RDAP Bootstrap Services Registries, listed below, and made them available as JSON objects. The contents of these registries are described in Section 3, Section 4, and Section 5, with the formal syntax specified in Section 10. The registries MUST be accessible only through HTTPS (TLS [RFC8446]) transport.\n\nThe process for adding or updating entries in these registries differs from the normal IANA registry processes: these registries are generated from the data, processes, and policies maintained by IANA in their allocation registries ([ipv4reg], [ipv6reg], [asreg], and [domainreg]), with the addition of new RDAP server information.\n\nIANA updates RDAP Bootstrap Services Registries entries from the allocation registries as those registries are updated.\nThis document does not change any policies related to the allocation registries; IANA has provided a mechanism for collecting the RDAP server information.\n\nIANA has created a new top-level category on the Protocol Registries page, <https://www.iana.org/protocols>. The group is called \"Registration Data Access Protocol (RDAP)\". Each of the RDAP Bootstrap Services Registries has been made available for general public on-demand download in the JSON format, and that registry’s URI is listed directly on the Protocol Registries page.\n\nOther normal registries will be added to this group by other documents, but the reason the URIs for these registries are clearly listed on the main page is to make those URIs obvious to implementers -- these are registries that will be accessed by software, as well as by humans using them for reference information.\n\nBecause these registries will be accessed by software, the download demand for the RDAP Bootstrap Services Registries may be unusually high compared to normal IANA registries. The technical infrastructure by which registries are published has been put in place by IANA to support the load. Since the publication of [RFC7484], no issue have been reported regarding the load or the service.\n\nAs discussed in Section 8, software that accesses these registries will depend on the HTTP Expires header field to limit their query rate. It is, therefore, important for that header field to be properly set to provide timely information as the registries change, while maintaining a reasonable load on the IANA servers.\n\nThe HTTP Content-Type returned to clients accessing these JSON-formatted registries MUST be \"application/json\", as defined in [RFC8259].\n\nBecause of how information in the RDAP Bootstrap Services Registries is grouped and formatted, the registry entries may not be sortable. It is, therefore, not required or expected that the entries be ordered in any way.\n\nNOTE TO IANA: Please update the registries to reference this new RFC instead of RFC 7484 once this document is approved by the IESG and published by the RFC Editor. RFC-Editor, please remove this paragraph before publication.\n13.1. Bootstrap Service Registry for IPv4 Address Space\n\nEntries in this registry contain at least the following:\n\n* a CIDR [RFC4632] specification of the network block being registered.\n* one or more URLs that provide the RDAP service regarding this registration.\n\n13.2. Bootstrap Service Registry for IPv6 Address Space\n\nEntries in this registry contain at least the following:\n\n* an IPv6 prefix [RFC5952] specification of the network block being registered.\n* one or more URLs that provide the RDAP service regarding this registration.\n\n13.3. Bootstrap Service Registry for AS Number Space\n\nEntries in this registry contain at least the following:\n\n* a range of Autonomous System numbers being registered.\n* one or more URLs that provide the RDAP service regarding this registration.\n\n13.4. Bootstrap Service Registry for Domain Name Space\n\nEntries in this registry contain at least the following:\n\n* a domain name attached to the root being registered.\n* one or more URLs that provide the RDAP service regarding this registration.\n\n14. References\n\n14.1. Normative References\n\n\n14.2. Informative References\n\nIANA, \"Root Zone Database\",\n<https://www.iana.org/domains/root/db>.\n\nIANA, \"IPv4 Address Space Registry\",\n<https://www.iana.org/assignments/ipv4-address-space>.\n\nIANA, \"IPv6 Global Unicast Address Assignments\",\n<https://www.iana.org/assignments/ipv6-unicast-address-assignments>.\n\n\nBorenstein, N. and M. Kucherawy, \"A Media Type for Reputation Interchange\", RFC 7071, DOI 10.17487/RFC7071,\n\nRFC 7234, DOI 10.17487/RFC7234, June 2014,\n\nHollenbeck, S. and N. Kong, \"Security Services for the Registration Data Access Protocol (RDAP)!\", STD 95,\nRFC 7481, DOI 10.17487/RFC7481, March 2015,\n\nBlanchet, M., \"Finding the Authoritative Registration Data (RDAP) Service\", RFC 7404, DOI 10.17487/RFC7404, March 2015,\n\nSheffer, Y. and A. Farrel, \"Improving Awareness of Running Code: The Implementation Status Section\", BCP 205,\nRFC 7942, DOI 10.17487/RFC7942, July 2016,\n\n\nHollenbeck, S. and A. Newton, \"Registration Data Access Protocol (RDAP) Object Tagging\", BCP 221, RFC 8521,\nDOI 10.17487/RFC8521, November 2018,\nAcknowledgements\n\nThe WEIRDS working group had multiple discussions on this topic, including a session during IETF 84, where various methods such as in-DNS and others were debated. The idea of using IANA registries was discovered by the author during discussions with his colleagues as well as by a comment from Andy Newton. All the people involved in these discussions are herein acknowledged. Linlin Zhou, Jean-Philippe Dionne, John Levine, Kim Davies, Ernie Dainow, Scott Hollenbeck, Arturo Servin, Andy Newton, Murray Kucherawy, Tom Harrison, Naoki Kambe, Alexander Mayrhofer, Edward Lewis, Pete Resnick, Alessandro Vesely, Bert Greevenbosch, Barry Leiba, Jari Arkko, Kathleen Moriarty, Stephen Farrell, Richard Barnes, and Jean-Francois Tremblay have provided input and suggestions to this document. Guillaume Leclanche was a coauthor of this document for some revisions; his support is therein acknowledged and greatly appreciated. The section on formal definition was inspired by Section 6.2 of [RFC7071]. This new version got comments and suggestions from: Gavin Brown, Patrick Mevzek, John Levine, Jas dip Singh, George Michaelson, Scott Hollenbeck, Russ Housley, Joel Halpern, Lars Eggert, Benjamin Kaduk, Scott Kelly, Eric Vyncke, John Scudder, Erik Kline, Robert Wilton. Errata of RFC7484 were submitted by Pieter Vandepitte and were applied to this version.\n\nChanges since RFC7484\n\nThere are no substantive changes except for updates to the implementation status and minor clarifications. This update is primarily to meet the requirements for moving to Internet Standard.\n\nAuthor’s Address\n\nMarc Blanchet\nViagenie\n246 Aberdeen\nQuebec QC G1R 2E1\nCanada\nEmail: Marc.Blanchet@viagenie.ca\nURI: https://viagenie.ca\nAbstract\n\nDomain name registries (the producer) and registrars (the consumer) report to each other by sharing bulk information through files. This document creates two IANA registries to establish a standard reporting mechanism between domain name registries and registrars. The first IANA registry lists standard data elements and their syntax for inclusion in the files. The second IANA registry lists standard reports based on the standard data elements. Each report is a file formatted as a CSV file. The advantage of this reporting mechanism is that a report, each file, can be imported by recipients without any prior knowledge of their contents, although reporting is enhanced with a minimum of knowledge about the files. The mechanism for the distribution of and access of the files is a matter of local policy.\n\nStatus of This Memo\n\nThis Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.\n\nInternet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.\n\nInternet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as \"work in progress.\"\n\nThis Internet-Draft will expire on 8 September 2022.\n\nCopyright Notice\n\nCopyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved.\nTable of Contents\n\n1. Introduction ..................................................... 3\n\n1.1. Requirements Language ........................................ 4\n\n2. Data Element Specification ....................................... 4\n\n2.1. General Information Data Elements .............................. 5\n\n2.1.1. TLD .......................................................... 5\n\n2.1.2. Server_TRID ................................................ 5\n\n2.1.3. Domain ...................................................... 5\n\n2.1.4. Transaction_Type ............................................ 5\n\n2.1.5. Object_Type ................................................ 5\n\n2.1.6. DateTime .................................................... 5\n\n2.1.7. Term ........................................................ 5\n\n2.1.8. Fee .......................................................... 6\n\n2.1.9. Currency ..................................................... 6\n\n2.1.10. Status ...................................................... 6\n\n2.1.11. Registrar ................................................... 6\n\n2.1.12. Period ...................................................... 6\n\n2.1.13. Description ............................................... 6\n\n2.2. Domain Price Data Elements ..................................... 6\n\n2.2.1. Domain_Create ............................................... 6\n\n2.2.2. Domain_Renew ................................................ 6\n\n2.2.3. Domain_Transfer ............................................. 7\n\n2.2.4. Domain_Restore .............................................. 7\n\n2.2.5. Trade ........................................................ 7\n\n2.3. Timestamp Data Elements ........................................ 7\n\n2.3.1. Start_Date .................................................. 7\n\n2.3.2. Deleted_Date ................................................ 7\n\n2.3.3. RGP_Date .................................................... 7\n\n2.3.4. Purge_Date .................................................. 7\n\n2.3.5. Updated_Date ................................................ 7\n\n2.3.6. Create_Date ................................................ 8\n\n2.3.7. Expiry_Date .................................................. 8\n\n2.4. Registration Information Data Elements ........................ 8\n\n2.4.1. Registrar_ID ............................................... 8\n\n2.4.2. Server_Registrant_ID ....................................... 8\n\n2.4.3. DNSSEC ...................................................... 8\n\n2.4.4. Server_Contact_ID ......................................... 8\n\n2.4.5. Contact_Type ............................................... 8\n1. Introduction\n\nCurrently, domain name registry operators (the producer) create and set their own domain name registration reports for use by their registrars (the consumer). Among the distinctions that vary by producer is the syntax of the data provided, e.g., date formats, and the format of the collection of the data provided, e.g., the report may be a CSV file that tends to allow for straightforward importation or a PDF file that can be problematic to import. In addition, although there are a number of best practice reports that have evolved, these are not currently documented as such, which results in a fair amount of customization on the part of the consumers to import data.\nThis document standardizes the name and syntax of the data elements to be used across all existing domain name registration reports and creates an IANA registry of them to facilitate their evolution, including adding additional data elements as needed. In addition, a known set of existing standard reports using the aforementioned data elements is specified in another IANA registry to facilitate the evolution of the reports and adding additional report definitions as needed.\n\nEach report definition MUST use only the data elements defined in the data element aforementioned data element registry, including all future reports. Note that a produced report MAY include data elements that are not registered, as specified below. Future reports and future data elements may be specified in their own individual documents, updating the IANA registries as needed.\n\nThe mechanism for the distribution of and access to the files is a matter of local policy.\n\n1.1. Requirements Language\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in RFC 2119 [RFC2119].\n\n2. Data Element Specification\n\nData elements are grouped into categories for convenience. There is no other significance to the groupings.\n\nEach data element conceptually represents the column heading in a printed report. It is a single unit of information that can be passed from the producer to the consumer. The primary purposes of the IANA registry of data elements are to ensure that each data element is assigned a unique name and that the syntax of each data element is specified.\n\nThe name of the data element MUST be unique and this characteristic MUST be enforced by the registry. The name is used in the report definition (in the next section) to alert the consumer as to what to expect in the file and how to import the data element. Character encoding recommendation for data elements is specified in Section 7.\nThe subsections below comprise an initial list of known data elements commonly being used between producers and consumers as of the date of publication of this document. The title of the subsection is the data element name for the data element. Data element names in the IANA registry MUST be unique and MUST be processed as case insensitive.\n\n2.1. General Information Data Elements\n\n2.1.1. TLD\n\nThe string of the top level domain involved that MUST be in A-label format as defined by RFC 5890 [RFC5890].\n\n2.1.2. Server_TRID\n\nThe transaction identifier issued by an EPP Server. The format MUST conform to \"type:trIDStringType\" as specified in RFC 5730 [RFC5730].\n\n2.1.3. Domain\n\nThis is the domain name in an EPP RFC 5731 [RFC5731] domain object and it MUST be in A-Label format.\n\n2.1.4. Transaction_Type\n\nThe type of transform action made to the domain object (e.g., create, delete, update, transfer, renew) as specified in RFC 5730 [RFC5730] Section 2.9.3.\n\n2.1.5. Object_Type\n\nThe object type involved in the report. In the EPP environment, an object could be domain RFC 5731 [RFC5731], contact RFC 5733 [RFC5733], or host RFC 5732 [RFC5732].\n\n2.1.6. DateTime\n\nThe timestamp of the transaction recorded in the system. Dates and Times MUST be expressed as defined in RFC 5731 [RFC5731] Section 2.4.\n\n2.1.7. Term\n\nThe number of units added to the domain registration period in <domain:period> RFC 5731 [RFC5731] in create, renew or transfer transforms. If there is no <domain:period>, the default value set out-of-band by the registry should be used.\n2.1.8. Fee\n\nThe amount of money charged or returned (shown as a negative value) to the registrar. The numeric format MUST conform to the currency specified below in Section 2.1.9. The format must conform to \"balanceType\" as defined in RFC 8748 [RFC8748].\n\n2.1.9. Currency\n\nThe currency used in the money charged as documented above in Section 2.1.8. The currency code should follow the ISO 4217 [ISO4217] standard.\n\n2.1.10. Status\n\nThe status of the domain object. It MUST be one of the values specified in RFC 5731 [RFC5731] Section 2.3.\n\n2.1.11. Registrar\n\nThe name of the registrar. This data element is text/string with no naming convention enforced.\n\n2.1.12. Period\n\nThe type of time (year, month) in 'Term' described above in Section 2.1.7. The value of 'year' and 'month' are referenced to pUnitType value 'y' and 'm' respectively. pUnitType is specified in RFC 5731 [RFC5731].\n\n2.1.13. Description\n\nAdditional information regarding the current entry in the report. It is provided by the producer and its actual value is a matter of local policy. This data element is text/string with no naming convention enforced.\n\n2.2. Domain Price Data Elements\n\n2.2.1. Domain_Create\n\nThe fee charged to create the domain. The format must conform to \"balanceType\" as defined in RFC 8748 [RFC8748].\n\n2.2.2. Domain_Renew\n\nThe fee charged to renew the domain. The format must conform to \"balanceType\" as defined in RFC 8748 [RFC8748].\n2.2.3. Domain_Transfer\n\nThe fee charged to transfer the domain. The format must conform to \"balanceType\" as defined in RFC 8748 [RFC8748].\n\n2.2.4. Domain_Restore\n\nThe fee charged to restore the domain. The format must conform to \"balanceType\" as defined in RFC 8748 [RFC8748].\n\n2.2.5. Trade\n\nThe fee charged to trade the domain. The format must conform to \"balanceType\" as defined in RFC 8748 [RFC8748].\n\n2.3. Timestamp Data Elements\n\n2.3.1. Start_Date\n\nThe timestamp of when the domain object becomes available. The date and time format follows the \"type=dateTime\" specification as defined in RFC 5731 [RFC5731].\n\n2.3.2. Deleted_Date\n\nThe timestamp of when the domain was deleted. The date and time format follows the \"type=dateTime\" specification as defined in RFC 5731 [RFC5731].\n\n2.3.3. RGP_Date\n\nThe timestamp of when the domain will complete its redemption grace period. The date and time format follows the \"type=dateTime\" specification as defined in RFC 5731 [RFC5731].\n\n2.3.4. Purge_Date\n\nThe timestamp of when the domain will be purged and become available again. The date and time format follows the \"type=dateTime\" specification as defined in RFC 5731 [RFC5731].\n\n2.3.5. Updated_Date\n\nThe timestamp of the last time the domain object was updated. The date and time format follows the \"type=dateTime\" specification as defined in RFC 5731 [RFC5731].\n2.3.6. Create_Date\n\nThe timestamp of when the domain object was allocated. The date and\ntime format follows the \"type=dateTime\" specification as defined in\nRFC 5731 [RFC5731].\n\n2.3.7. Expiry_Date\n\nThe timestamp of when the domain object will expire. The date and\ntime format follows the \"type=dateTime\" specification as defined in\nRFC 5731 [RFC5731].\n\n2.4. Registration Information Data Elements\n\n2.4.1. Registrar_ID\n\nThe identifier assigned to the registrar. If the registrar is\naccredited under ICANN, it MUST be the registrar’s IANA ID\n[IANA_Registrar_IDs]. Otherwise it is a value known between the\nproducer and the consumer, set via an out-of-band mechanism and\nunique within all reports of the producer.\n\n2.4.2. Server_Registrant_ID\n\nThe identifier, issued by EPP server, assigned to the contact object\nthat is associated as registrant of the domain name that MUST conform\nto \"clIDType\" specified in RFC 5730 [RFC5730].\n\n2.4.3. DNSSEC\n\nThe value MUST be either 'YES' or 'NO' to indicate whether the domain\nis DNSSEC signed.\n\n2.4.4. Server_Contact_ID\n\nThe identifier of the contact object assigned by the registry system\nand MUST conform to \"clIDType\" specified in RFC 5730 [RFC5730].\n\n2.4.5. Contact_Type\n\nThe value MUST be one of value as defined by \"contactAttrType\" in RFC\n5731 [RFC5731].\n\n2.4.6. Contact_Name\n\nThe name of the contact object. Usually it is the name of an\nindividual or an organization as described in RFC 5733 [RFC5733]\nSection 2.3.\n2.4.7. In_use\n\nThe value MUST be either \"YES\" or \"NO\" to indicate whether the contact object is associated with a domain object.\n\n2.4.8. Nameserver_Host\n\nThe full domain name of the host object as defined in RFC 5732 [RFC5732] Section 2.1. The name MUST be in A-label format as defined by RFC5890 [RFC5890].\n\n2.4.9. Nameserver_IP\n\nThe IP address of the host object. The syntax of the IPv4 address MUST conform to RFC 791 [RFC0791]. The syntax of the IPv6 address MUST conform to RFC 4291 [RFC4291].\n\n2.4.10. Client_Contact_ID\n\nThe identifier of the contact object assigned by the registrar and MUST conform to \"clIDType\" specified in RFC 5730 [RFC5730].\n\n3. Report Definition Specification\n\nEach report specification conceptually represents a file of comma separated values [RFC4180] (commonly called a CSV file) where the values are selected from the data elements specified above. The first row of the file is a comma separated list of data element names as specified in the data element registry. The remaining rows of the file are the unordered sets of data elements, one set per row, where each row is one transaction in the report.\n\nEach data element in a set conceptually represents the column heading in a printed report.\n\nA consumer MUST be able to receive data elements that are not recognized and MAY skip them accordingly, both in the header row and in the transaction rows.\n\nA report is specified in the report registry with two pieces of information. First is the name of the report. This can be whatever is appropriate as defined by the producer of the report. The name of the report MUST be unique and this characteristic MUST be enforced by registry.\nSecond is the ordered list of data element names of what is included in the report. The data element names MUST be listed in the data element registry specified above. The data element names and the data MUST appear in the report in the order listed in the report registry.\n\nThe subsections below comprise an initial list of standard reports commonly being used between producers and consumers as of the date of publication of this document. The title of the subsection is the report name. The report name in the IANA registry MUST be unique and MUST be processed as case insensitive.\n\n3.1. Domain Transaction\n\nName of report: domain_transaction\n\n<table>\n<thead>\n<tr>\n<th>Data Element</th>\n<th>Reference</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>TLD</td>\n<td>RFC XXXX Section 2.1.1</td>\n</tr>\n<tr>\n<td>Server_TRID</td>\n<td>Section 2.1.2</td>\n</tr>\n<tr>\n<td>Domain</td>\n<td>Section 2.1.3</td>\n</tr>\n<tr>\n<td>DateTime</td>\n<td>Section 2.1.6</td>\n</tr>\n<tr>\n<td>Registrar_ID</td>\n<td>Section 2.4.1</td>\n</tr>\n<tr>\n<td>Registrar</td>\n<td>Section 2.1.11</td>\n</tr>\n<tr>\n<td>Transaction_Type</td>\n<td>Section 2.1.4</td>\n</tr>\n<tr>\n<td>Period</td>\n<td>Section 2.1.12</td>\n</tr>\n<tr>\n<td>Term</td>\n<td>Section 2.1.7</td>\n</tr>\n<tr>\n<td>Fee</td>\n<td>Section 2.1.8</td>\n</tr>\n<tr>\n<td>Currency</td>\n<td>Section 2.1.9</td>\n</tr>\n<tr>\n<td>Description</td>\n<td>Section 2.1.13</td>\n</tr>\n</tbody>\n</table>\n\nTable 1: Transaction Report Definition Table\n3.2. Premium Name\n\nName of report: premium_name\n\n<table>\n<thead>\n<tr>\n<th>Data Element</th>\n<th>Reference</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>TLD</td>\n<td>RFC XXXX Section 2.1.1</td>\n</tr>\n<tr>\n<td>Domain</td>\n<td>Section 2.1.3</td>\n</tr>\n<tr>\n<td>Status</td>\n<td>Section 2.1.10</td>\n</tr>\n<tr>\n<td>Description</td>\n<td>Section 2.1.13</td>\n</tr>\n<tr>\n<td>Currency</td>\n<td>Section 2.1.9</td>\n</tr>\n<tr>\n<td>Domain_Create</td>\n<td>Section 2.2.1</td>\n</tr>\n<tr>\n<td>Domain_Renew</td>\n<td>Section 2.2.2</td>\n</tr>\n<tr>\n<td>Domain_Transfer</td>\n<td>Section 2.2.3</td>\n</tr>\n<tr>\n<td>Domain_Restore</td>\n<td>Section 2.2.4</td>\n</tr>\n<tr>\n<td>Start_Date</td>\n<td>Section 2.3.1</td>\n</tr>\n</tbody>\n</table>\n\nTable 2: Premium Name Report Definition Table\n\n3.3. Domain RGP\n\nName of report: domain_rgp\nTable 3: Domain RGP Report Definition\n\n3.4. Reserved Domain\n\nName of report: reserved_domain\n\nTable 4: Reserved Domain Report Definition Table\n\n3.5. Domain Inventory\n\nName of report: domain_inventory\nTable 5: Domain Inventory Report Definition Table\n\n3.6. Contact Inventory\n\nName of report: contact_inventory\nTable 6: Contact Inventory Report\nDefinition Table\n\n3.7. Host Inventory\n\nName of report: host_inventory\n\nTable 7: Host Inventory Report\nDefinition Table\n\n4. IANA Considerations\n\nThis section describes the format of the IANA Registration Report Registry, which has two tables described below, and the procedures used to populate and manage the registry entries.\n4.1. Report Specification\n\nThis registry uses the \"Specification Required\" policy described in RFC 8126 [RFC8126]. An English language version of the extension specification is required in the registry, though non-English versions of the specification may also be provided.\n\nThe \"Specification Required\" policy implies review by a \"designated expert\". Section 5.2 of RFC 8126 [RFC8126] describes the role of designated experts and the function they perform.\n\n4.1.1. Designated Expert Evaluation Criteria\n\nA high-level description of the role of the designated expert is described in Section 5.2 of RFC 8126 [RFC8126]. Specific guidelines for the appointment of designated experts and the evaluation of a Registration Report is provided here.\n\nThe IESG SHOULD appoint a small pool of individuals (perhaps 3 - 5) to serve as designated experts, as described in Section 5.2 of RFC 8126 [RFC8126]. The pool should have a single administrative chair who is appointed by the IESG. The designated experts should use the existing regext mailing list (regext@ietf.org) for public discussion of registration requests. This implies that the mailing list should remain open after the work of the REGEXT working group has concluded.\n\nThe results of the evaluation should be shared via email with the registrant and the regext mailing list. Issues discovered during the evaluation can be corrected by the registrant, and those corrections can be submitted to the designated experts until the designated experts explicitly decide to accept or reject the registration request. The designated experts must make an explicit decision and that decision must be shared via email with the registrant and the regext mailing list. If the specification for a data element or report is an IETF Standards Track document, no review is required by the designated expert.\n\nDesignated experts should be permissive in their evaluation of requests for data elements and reports that have been implemented and deployed by at least one registry. This implies that it may indeed be possible to register multiple data elements or reports that provide the same functionality. Requests to register data elements or reports that have not been deployed should be evaluated with a goal of reducing duplication. A potential registrant who submits a request to register a new data element or report that includes similar functionality to existing data elements or reports should be made aware of the existing data elements and reports. The registrant should be asked to reconsider their request given the existence of\nsimilar data elements or reports. Should they decline to do so, perceived similarity should not be a sufficient reason for rejection as long as all other requirements are met.\n\n4.1.2. Registration Procedure\n\nThe registry contains information describing each registered data element or report. Registry entries are created and managed by sending forms to IANA that describe the data element or report for the registry entry.\n\n4.1.2.1. Required Information\n\nThe required information must be formatted consistently using the following registration form. Form field names and values may appear on the same line.\n\n4.1.2.1.1. Data Element Definition\n\nName of data element\n MUST be unique within the registry, enforced to be unique, and MUST be processed as case insensitive\n\nReference document\n MUST define the data element, SHOULD be a URL to a RFC, and SHOULD include the section number (or other detailed internal document reference), MAY be a URL to any document available under equivalent terms\n\nRegistrant\n Will be IESG for initial entries and all Standards Track specifications; otherwise as specified by the registrant\n\nStatus\n MUST be one of active, inactive, or unknown\n\n4.1.2.1.2. Report Definition\n\nName of Report\n MUST be unique within the registry, enforced to be unique, and MUST be processed as case insensitive\n\nDocument Status\n MUST be one of active, inactive, or unknown\nReference document\nMUST define the report, SHOULD be a URL to a RFC and SHOULD include the section number (or other detailed internal document reference), MAY be a URL to any document available under equivalent terms\n\nRegistrant\nWill be IESG for initial entries and all Standards Track specifications; otherwise as specified by the registrant\n\nTLD\nMUST be \"ANY\" if the report is intended to be generally applicable or MAY be any top level domain formatted as defined by RFC 5890 [RFC5890] (or comma separated list of domains) and each MUST be an A-LABEL if the report is intended to have that scope\n\nStatus:active\n\n4.1.2.2. Registration Processing\n\nRegistrants should send each registration form to IANA with a single record for incorporation into the registry. Send the form via email to iana@iana.org or complete the online form found on the IANA website. The subject line should indicate whether the enclosed form represents an insertion of a new record (indicated by the word \"INSERT\" in the subject line) or a replacement of an existing record (indicated by the word \"MODIFY\" in the subject line). At no time can a record be deleted from the registry. On receipt of the registration request, IANA will initiate review by the designated expert(s) if appropriate, who will evaluate the request using the criteria in Section 4.1.1 in consultation with the regext mailing list.\n\n4.1.2.3. Updating Report Definition Registry Entries\n\nWhen submitting changes to existing registry entries, include text in the \"Notes\" field of the registration form describing the change. Under normal circumstances, registry entries are only to be updated by the registrant. If the registrant becomes unavailable or otherwise unresponsive, the designated expert can submit a registration form to IANA to update the registrant information. Entries can change state from \"Active\" to \"Inactive\" and back again as long as state-change requests conform to the processing requirements identified in this document. In addition to entries that become \"Inactive\" due to a lack of implementation, entries for which a specification becomes consistently unavailable over time should be marked \"Inactive\" by the designated expert until the\nspecification again becomes reliably available.\n\n4.2. Initial assignments\n\n4.2.1. Data Element Definition in IANA Registry\n\n---- BEGIN FORM ----\n\nName of data element:\nTLD\n\nReference:\nThis RFC Section 2.1.1\n\nRegistrant:\nIESG, iesg@ietf.org\n\nStatus:\nActive\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\nServer_TRID\n\nReference:\nThis RFC Section 2.1.2\n\nRegistrant:\nIESG, iesg@ietf.org\n\nStatus:\nActive\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\nDomain\n\nReference:\nThis RFC Section 2.1.3\n\nRegistrant:\nIESG, iesg@ietf.org\nStatus:\n Active\n\nName of data element:\n Transaction_Type\n\nReference:\n This RFC Section 2.1.4\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n Object_Type\n\nReference:\n This RFC Section 2.1.5\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n DateTime\n\nReference:\n This RFC Section 2.1.6\n\nRegistrant:\n IESG, iesg@ietf.org\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\n Currency\n\nReference:\n This RFC Section 2.1.9\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\n Status\n\nReference:\n This RFC Section 2.1.10\n\nRegistrant:\n IESG, iesg@ietf.org\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\n Term\n\nReference:\n This RFC Section 2.1.7\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\n Registrar\n\nReference:\n This RFC Section 2.1.11\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\n Period\n\nReference:\n This RFC Section 2.1.12\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\n Description\n\nReference:\n This RFC Section 2.1.13\n\nRegistrant:\n IESG, iesg@ietf.org\nStatus:\n Active\n\nName of data element:\n Domain_Create\n\nReference:\n This RFC Section 2.2.1\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n Domain_Renew\n\nReference:\n This RFC Section 2.2.2\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n Domain_Transfer\n\nReference:\n This RFC Section 2.2.3\n\nRegistrant:\n IESG, iesg@ietf.org\nStatus:\n Active\n\nName of data element:\n Domain_Restore\n\nReference:\n This RFC Section 2.2.4\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n Start_Date\n\nReference:\n This RFC Section 2.3.1\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n Deleted_Date\n\nReference:\n This RFC Section 2.3.2\n\nRegistrant:\n IESG, iesg@ietf.org\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\n RGP_Date\n\nReference:\n This RFC Section 2.3.3\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\n Purge_Date\n\nReference:\n This RFC Section 2.3.4\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of data element:\n Updated_Date\n\nReference:\n This RFC Section 2.3.5\n\nRegistrant:\n IESG, iesg@ietf.org\nStatus:\n Active\n\nName of data element:\nCreate_Date\n\nReference:\n This RFC Section 2.3.6\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\nExpiry_Date\n\nReference:\n This RFC Section 2.3.7\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\nRegistrar_ID\n\nReference:\n This RFC Section 2.4.1\n\nRegistrant:\n IESG, iesg@ietf.org\nStatus:\n Active\n\nName of data element:\n Server_Registrant_ID\n\nReference:\n This RFC Section 2.4.2\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n DNSSEC\n\nReference:\n This RFC Section 2.4.3\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n Server_Contact_ID\n\nReference:\n This RFC Section 2.4.4\n\nRegistrant:\n IESG, iesg@ietf.org\nName of data element: Contact_Type\nReference:\n This RFC Section 2.4.5\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element: Contact_Name\nReference:\n This RFC Section 2.4.6\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element: INUSE\nReference:\n This RFC Section 2.4.7\nRegistrant:\n IESG, iesg@ietf.org\nStatus:\n Active\n\nName of data element:\n Nameserver_Host\n\nReference:\n This RFC Section 2.4.8\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n Nameserver_IP\n\nReference:\n This RFC Section 2.4.9\n\nRegistrant:\n IESG, iesg@ietf.org\n\nStatus:\n Active\n\nName of data element:\n Client_Contact_ID\n\nReference:\n This RFC Section 2.4.10\n\nRegistrant:\n IESG, iesg@ietf.org\n4.2.2. Report Definition in IANA Registry\n\n----- BEGIN FORM -----\nName of report:\n domain_transaction\nReference:\n This RFC Table 1\nRegistrant:\n IESG, iesg@ietf.org\nTLD:\n any\nStatus:\n Active\n----- END FORM -----\n\n----- BEGIN FORM -----\nName of report:\n premium_name\nReference:\n This RFC Section 3.2\nRegistrant:\n IESG, iesg@ietf.org\nTLD:\n any\nStatus:\n Active\n----- END FORM -----\n----- BEGIN FORM -----\n\nYee & Galvin Expires 8 September 2022 [Page 29]\nName of report:\ndomain_rgp\n\nReference:\nThis RFC Section 3.3\n\nRegistrant:\nIESG, iesg@ietf.org\n\nTLD:\nany\n\nStatus:\nActive\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of report:\nreserved_domain\n\nReference:\nThis RFC Section 3.4\n\nRegistrant:\nIESG, iesg@ietf.org\n\nTLD:\nany\n\nStatus:\nActive\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of report:\ndomain_inventory\n\nReference:\nThis RFC Section 3.5\n\nRegistrant:\nIESG, iesg@ietf.org\nTLD:\n any\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of report:\n contact_inventory\nReference:\n This RFC Section 3.6\nRegistrant:\n IESG, iesg@ietf.org\n\nTLD:\n any\nStatus:\n Active\n\n---- END FORM ----\n\n---- BEGIN FORM ----\n\nName of report:\n host_inventory\nReference:\n This RFC Section 3.7\nRegistrant:\n IESG, iesg@ietf.org\n\nTLD:\n any\nStatus:\n Active\n\n---- END FORM ----\n5. Security Considerations\n\nThis specification does not consider the issues of distribution or access to the reports that are created and thus does not introduce any new security security concerns that are not already present in the local environment in which the report is created.\n\nA security principle to keep in mind as new reports are developed is that it is considered a bad practice to report or disclose security information. In the case of the registration system upon which this reporting mechanism is based, the authInfo code is a specific example of a data element that SHOULD NOT be included in a report.\n\n6. Privacy Considerations\n\nThis specification defines a mechanism for creating reports based on data in a registration system. Some of that data is likely to be considered personally identifiable information (PII) and thus would be subject to privacy protection according to an applicable privacy regulation. It is outside the scope of this specification to address those specific concerns. Implementors are urged to consider these issues with their local legal authority and develop appropriate requirements for their work.\n\nAs expressly noted in the Introduction, distribution of and access to the reports created by this specification is expressly outside the scope of this specification. However, to the extent a report contains PII, implementors are urged to consider these issues with their local legal authority and develop appropriate requirements for their work.\n\n7. Internationalization Considerations\n\nThe character encoding for the file contents MUST use UTF-8.\n\nThroughout this document A-LABEL is indicated as a SHOULD and that MUST be interpreted as follows. All domain name labels MUST be in A-LABEL format if it is possible to represent it as an A-LABEL, otherwise U-LABEL MAY be used.\n\n8. References\n\n8.1. Normative References\n\n\n8.2. Informative References\n\nAppendix A. Acknowledgements\n\nThe authors would like to thank Roger Carney, Jody Kolker, Tobias Sattler, and bestpractice.domains for their reviews and suggestions.\n\nAppendix B. File Naming Convention\n\nTBD on file naming convention suggestion\n\nAuthors’ Addresses\n\nJoseph Yee (editor)\nDonuts\nToronto\nCanada\nEmail: jyee@afilias.info\n\nJames Galvin\nDonuts\nHorsham, PA\nUnited States\nEmail: jgalvin@donuts.email\nAbstract\n\nThis document describes how the Extensible Provisioning Protocol (EPP) is mapped over the Hypertext Transfer Protocol (HTTP). This mapping requires the use of the Transport Layer Security (TLS) protocol to protect information exchanged between an EPP client and an EPP server.\n\nStatus of This Memo\n\nThis Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.\n\nInternet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.\n\nInternet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as \"work in progress.\"\n\nThis Internet-Draft will expire on 8 September 2022.\n\nCopyright Notice\n\nCopyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved.\n\nThis document is subject to BCP 78 and the IETF Trust’s Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document.\n1. Introduction\n\nAlthough the Extensible Provisioning Protocol (EPP) core specification [RFC5730] does not state the transport protocol, only the mapping over TCP [RFC5734] has been standardized thus far. Nevertheless, some EPP implementations leverage HTTP due to its ease of use and simplicity. This document describes the reasons behind using HTTP as the transport protocol for EPP and how EPP is mapped over HTTP preserving the semantics of commands.\n\nHTTP is defined in some IETF documents according to the versions currently in use: HTTP/1.1 [RFC7230], HTTP/2 [RFC7540], HTTP/3 [I-D.ietf-quic-http]. As the differences among such versions do not affect the EPP mapping, hereinafter the version number is omitted except for presenting the special features in the underlying layers of the HTTP stack.\n\nSecurity services beyond those defined in EPP are provided by the Transport Layer Security (TLS) protocol [RFC8446].\n1.1. Conventions Used in This Document\n\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"NOT RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.\n\n2. Reasons behind Using HTTP\n\nUnlike TCP, HTTP is loosely coupled with the network and provides client-server cross-platform technology communication. Indeed, since an HTTP connection is a higher-level abstraction of a network connection, there is no need to take over all of the lower-level details of TCP. For example, while in TCP the data transmission between a client and a server starts only after having established a connection through a 3-way handshake (i.e. SYN, SYN-ACK, ACK), HTTP uses a one-way communication so that a client can directly issue a request to a server and then receive a response.\n\nAll the burden needed to manage the HTTP connections is usually performed by an application server, which a service can be deployed on. Service implementors are only required to process the requests and return the responses. Definitively, HTTP ease of use and simplicity reduces the development time.\n\nWhile TCP is connection-oriented, HTTP is stateless but not session less. This means that, by making an EPP session untied from the network connection, the EPP communication over HTTP is more flexible and efficient than over TCP.\n\nThe main reason supporting the usage of TCP has always been its speed. TCP has been significantly faster than HTTP as HTTP was initially built on top of TCP so that every HTTP request should be issued on a new TCP connection. However, subsequent HTTP versions have been defined over time to increase the protocol speed and reduce the gap with TCP:\n\n* Compared to the original HTTP specification, HTTP/1.1 introduced the \"keep-alive\" connection by default to enable a request-response sequence on a single TCP connection without repeating the connection handshake at each request;\n* As opposed to HTTP/1.1, which keeps all requests and responses in plain text format, HTTP/2 defined the binary framing layer to encapsulate all messages in binary format;\n* HTTP/3 is based on QUIC transport protocol [I-D.ietf-quic-transport]. QUIC uses UDP [RFC768] instead of TCP to exchange packets between the client and the server. It\nincorporates TLS whereas HTTP/1.1 and HTTP/2 define TLS as an add-on. So doing, HTTP/3 can provide a very quick handshake to establish a secure connection.\n\nIn the perspective of moving to the cloud to achieve scalability and cost reduction, it should be further noted that application protocols that aren’t based on HTTP can be hardly migrated by using cloud-native features, both on client side and server side. In addition, from the security point of view, registries would be limited in terms of the third-party security services available to protect their EPP servers.\n\nFinally, some considerations should be done about load balancing which is generally used by EPP operators to distribute the requests across a pool of servers and, consequently, provide an efficient domains registration and maintenance service. While HTTP load balancers are very common and are quite often software, TCP load balancers are usually implemented in dedicated hardware. In addition, HTTP load balancers don’t merely forward the traffic but can make high-level routing decisions based on the message content. With regard to the performance, although HTTP load balancers do more work, their throughput is evaluated considerably fast.\n\nAdditional notes on how EPP sessions can be managed in HTTP load balancing are included in Appendix A.\n\n3. Message Exchange\n\nEPP describes client-server interaction as a command-response exchange where the client sends one command to the server and the server returns one response to the client. A client MUST use the POST method (Section 3.3 of [RFC7231]) to issue an EPP command through the request body. A server receiving a request MUST return an EPP message in the response body using the \"Content-Length\" entity-header field to indicate the length in decimal number of OCTETs of the entity-body. No EPP message information MUST be issued through any other part of the request or the response. If the HTTP connection is closed after a server receives and successfully processes a command but before the response can be returned to the client, the server MAY attempt to undo the effects of the command to ensure a consistent state between the client and the server.\n\nCommands MUST be processed independently and in the same order as received from the server. An EPP client MAY issue multiple EPP commands to an EPP server on an HTTP connection by relying on the HTTP keep-alive capability. A server SHOULD limit a client to a maximum number of HTTP connections based on server capabilities and operational load.\nA client might be able to realize a slight performance gain by pipelining the requests, but this feature does not change the basic single command, single response operating mode of the EPP protocol. A server SHOULD limit the amount of time required for a client to issue a well-formed EPP command and, consequently close an open HTTP connection.\n\n4. Session Management\n\nThe EPP session is implemented by using the mechanism described in [RFC6265]. An EPP session is started by the client issuing an EPP <login> command. A server receiving an EPP <login> command MUST use the \"Set-Cookie\" response header to send the client a token that the client will return in future requests within the scope of the EPP session. For example (Figure 1), the server can send the client a \"session identifier\" (a.k.a \"session ID\") named SID. The client then returns the session ID in the \"Cookie\" header of the subsequent requests.\n\n```\n== Server -> Client ==\nSet-Cookie: SID=52ceb07c2a824f09a1c6f9c45574097d\n\n== Client -> Server ==\nCookie: SID=52ceb07c2a824f09a1c6f9c45574097d\n```\n\nFigure 1\n\nThe name of the cookie attribute identifying the session ID is not relevant and depends on the implementations. Examples of the names that some programming languages use to represent the session ID include JSESSIONID (Java EE), PHPSESSID (PHP), and ASPSESSIONID (Microsoft ASP).\n\nAn EPP session is ended by the client issuing an EPP <logout> command. A server receiving an EPP <logout> command MUST end the EPP session invalidating it after having issued the <logout> response.\n\nA client MAY open multiple EPP sessions and distribute commands from a single EPP session over multiple HTTP connections. A server SHOULD limit a client to a maximum number of EPP sessions based on server capabilities and operational load.\n\nEPP sessions that are inactive for more than a server-defined period MAY be ended by a server invalidating the session.\nClients MAY issue the <hello> command outside an EPP session. In such a case, servers MUST return the <greeting> response without starting a session. To accomplish this, a server MAY return no cookie at all or provide the client with an expired cookie so that it cannot be used for further communication with the server. Clients MAY also issue the <hello> command within an EPP session to keep it alive.\n\nThe mechanism implemented by a server to maintain the relationship between a session and the EPP information negotiated with the client through the <login> command (e.g. the language, the namespace URIs representing both the objects and the extensions to be managed during the session) is out of the scope of this document.\n\nThe state machine described in Section 2 of [RFC5730] is updated as shown in Figure 2.\nFigure 2\n5. Return Codes\n\nServers MUST NOT use HTTP return codes to signal clients about the failure of the EPP commands. The HTTP code 200 MUST be used for both successful and unsuccessful EPP requests. Servers MUST use HTTP codes to signal clients about the failure of the HTTP requests.\n\nServers MUST return a 2002 response (i.e. Command use error) if the client issues an EPP command other than the <hello> and the <login> commands through HTTP requests including either an empty or an invalid session ID. Servers receiving a <login> command through an HTTP request including a session ID MAY return a 2002 response (i.e. Command use error) or simply ignore the incoming session ID.\n\n6. Implementation Status\n\nNOTE: Please remove this section and the reference to RFC 7942 prior to publication as an RFC.\n\nThis section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in [RFC7942]. The description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist.\n\nAccording to RFC 7942, \"this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit\".\n\n6.1. IIT-CNR/Registro.it EPP Server\n\n* Responsible Organization: Institute of Informatics and Telematics of National Research Council (IIT-CNR)/Registro.it\n* Location: https://epp.nic.it/ EPP endpoint available only \"per IP address\" basis.\n* Description: The .it EPP server is deployed on WildFly Application Server. TLS versions supported are 1.2 and 1.3. Load balancing is implemented with NGINX. EPP sessions are maintained on a Redis cluster.\n* Level of Maturity: This is a live implementation.\n* Coverage: This implementation includes all of the features described in this specification except for the media type that is currently set to \"text/xml\".\n* Contact Information: Mario Loffredo, mario.loffredo@iit.cnr.it\n\n6.2. .pl domain Registry (NASK) EPP Server\n\n* Responsible Organization: .pl domain Registry (NASK)/dns.pl\n* Location: https://dns.pl EPP endpoint available only \"per IP address\" basis.\n* Description: It is an implementation of the EPP protocol that is used by .pl Registry.\n* Level of Maturity: This is a live implementation.\n* Coverage: This implementation includes all of the features described in this specification.\n* Contact Information: Marcin Machnio, info@dns.pl\n\n7. Transport Considerations\n\nSection 2.1 of the EPP core specification [RFC5730] describes considerations to be addressed by protocol transport mappings. This document addresses each of the considerations using a combination of features described in this document and features provided by HTTP as follows:\n\n* Sections 3.3.3 and 3.9.3 of [RFC8095] includes features to provide reliability, flow control, ordered delivery, and congestion control of, respectively, UDP and HTTP over TCP as Pseudotransport.\n* Section 3 and Section 4 of this document describe how the stateful nature of EPP is preserved through controlled message exchanges and managed sessions.\n* Section 3 of this document notes that command pipelining is possible with HTTP, though batch-oriented processing (combining multiple EPP commands in a single HTTP request) is not permitted.\n\n8. IANA Considerations\n\nThis document has no actions for IANA.\n9. Internationalization Considerations\n\nServers MUST use the \"charset\" attribute in the HTTP \"Content-Type\" response header field to specify the UTF-8 character encoding (e.g. Content-Type: application/epp+xml; charset=UTF-8).\n\n10. Security Considerations\n\nSince clients credentials are included in the EPP <login> command, the HTTP over TLS [RFC8740] MUST be used to protect them from disclosure while in transit. As well, the transfer over TLS prevents from sniffing the session ID and, consequently, impersonating a client to perform actions on registrars’ objects.\n\nAnyway, servers are RECOMMENDED to implement additional measures to verify the client. These measures include IP whitelisting and locking the session ID to the client’s IP address.\n\nAs a further measure to enforce the security, servers MAY require clients to present a digital certificate. Clients who possess and present a valid X.509 digital certificate, issued by a recognized Certification Authority (CA), could be identified and authenticated by a server who trusts the corresponding CA. This certificate-based mechanism is supported by HTTPS and can be used with EPP over HTTP. The TLS protocol describes the specification of a client certificate in Section 7.4.6 of [RFC8446].\n\nWith regard to sessions, session IDs SHOULD be randomly generated to mitigate the risk of obtaining a valid one through a brute-force search. A session ID SHOULD be at least 128 bits or 16 bytes long. An example of a reliable session ID is the Universally Unique Identifier (UUID). Servers MAY limit the lifetime of active sessions to avoid them being exchanged for a long time.\n\nThe following measures MAY also be taken to control cookies usage:\n\n- restricting their scope through the \"Domain\" and \"Path\" attributes;\n- limiting their lifetime through the \"Max-Age\" and \"Expire\" attributes.\n\nOther attributes that are normally used to secure the cookies and prevent them to be accessed from unintended parties or scripts, such as \"HttpOnly\" and \"Secure\", are meaningless in this context.\nFinally, servers are RECOMMENDED to perform additional checks to limit the rate of open EPP sessions and HTTP connections to mitigate the risk of congestion of requests. Here again, IP whitelisting could also be implemented to prevent DDoS attacks.\n\nIf the EPP server is configured as a load balancer routing the requests to a pool of backend servers, some of the aforementioned checks SHOULD be implemented on the load balancer side.\n\n11. Acknowledgements\n\nThe authors would like to acknowledge the following individuals for their contributions to this document: Cristian Lucchesi, Stefano Ruberti, Luca Vasarelli, Roberto Ravazzolo from IIT-CNR/Registro.it and Adrian Prokop, Sławomir Mateuszczynk from NASK/.pl Registry.\n\n12. References\n\n12.1. Normative References\n\n\n12.2. Informative References\n\n\nAppendix A. Notes on Load Balancing\n\nAn EPP server should be able to serve a large number of concurrent requests from clients and return the responses in a fast and reliable manner. In addition, since EPP is extensible, EPP servers might be updated and the replacement of an EPP server with a new version should take place in accordance with the service level agreement negotiated between the registry and the registrars. To cost-effectively scale high volumes of requests and redeploy a server without affecting its functioning, best practice in providing a software service generally requires using load balancing. This section presents two possible approaches to the implementation of a HTTP load balancing solution for an EPP server.\n\nAn EPP server made up of a server pool must always operate with respect to the constraint that, once an EPP session is established, all the requests related to that session should be processed by the servers in the pool as long as the session is alive.\n\nOne possible approach is using sticky sessions. In this case, the load balancer assigns an identifier to each client issuing a request. Then, according to such identifier, the load balancer can route all of the requests of a given client to the backend server that started the session for its entire duration. This approach requires each backend server to maintain the EPP information connected to the sessions opened by that server. This means that when a backend server is stopped and then restarted after its update, all the sessions currently active and managed by that server are lost.\nA more efficient solution consists in releasing the sessions from the server pool. According to this approach, every session is stored somewhere outside the server pool. The load balancer distributes the request based on the load of each backend server and according to a specific algorithm. When a server receives a request, it first retrieves the session information by the session ID and, if any, processes the request. Sessions are normally stored in a cluster of NO-SQL databases so that performance and efficiency requirements are fulfilled. In this approach, only the ongoing requests are lost when a backend server is stopped and restarted. Moreover, maintaining the sessions on a persistent data storage results in supporting a virtually unlimited number of concurrent sessions.\n\nAuthors’ Addresses\n\nMario Loffredo \nIIT-CNR/Registro.it \nVia Moruzzi,1 \n56124 Pisa \nItaly \nEmail: mario.loffredo@iit.cnr.it \nURI: https://www.iit.cnr.it\n\nLorenzo Luconi Trombacchi \nIIT-CNR/Registro.it \nVia Moruzzi,1 \n56124 Pisa \nItaly \nEmail: lorenzo.luconi@iit.cnr.it \nURI: https://www.iit.cnr.it\n\nMaurizio Martinelli \nIIT-CNR/Registro.it \nVia Moruzzi,1 \n56124 Pisa \nItaly \nEmail: maurizio.martinelli@iit.cnr.it \nURI: https://www.iit.cnr.it\n\nJan Romanowski \nNASK/.pl Registry \nKolska 12 \n01-045 Warszawa \nPoland \nEmail: jan.romanowski@nask.pl\nURI: https://www.dns.pl/\n\nMarcin Machnio\nNASK/.pl Registry\nKolska 12\n01-045 Warszawa\nPoland\nEmail: info@dns.pl\nURI: https://www.dns.pl/"}}},{"rowIdx":68,"cells":{"id":{"kind":"string","value":"fe12ce0c47f59f7915e2a4d082a11e2a12193c2c"},"text":{"kind":"string","value":"Grammar Transformations for Comparing Modelica Versions\n\nJuly 1, 2013\n\nTanya Braun\n\nsupervised by:\nProf. Dr. Sibylle Schupp\nDipl.-Ing. Timo Kamph\n\nHamburg University of Technology (TUHH)\nTechnische Universität Hamburg-Harburg\nInstitute for Software Systems\n21073 Hamburg\nEidesstattliche Erklärung\n\nIch versichere an Eides statt, dass ich die vorliegende Bachelorarbeit selbstständig verfasst und keine anderen als die angegebenen Quellen und Hilfsmittel verwendet habe. Die Arbeit wurde in dieser oder ähnlicher Form noch keiner Prüfungskommission vorgelegt.\n\nHamburg, den 01.07.2013\n\n______________________________\nTanya Braun\nE.13 Refactoring of Access Expressions ......................... 114\nE.14 Refactoring of Named Arguments .............................. 115\nE.15 Refactoring of Partial Function Calls ......................... 115\nE.16 Refactoring of Function Calls and Function Arguments ............ 116\nE.17 Elimination of Redundant Choices .............................. 116\nE.18 Final Refactorings for Clarification of Differences .............. 116\nE.19 Renaming of Terminals ......................................... 117\nE.20 Refactoring of Subscripts ...................................... 118\nE.21 Refactoring of Expression Lists ............................... 118\nE.22 Refactoring of Relational Operators .............................. 119\nE.23 Refactoring of Multiplicative Operators ......................... 119\nE.24 Refactoring of Unary Expressions .............................. 119\nE.25 Refactoring of If Expressions ................................ 120\nE.26 Refactoring of Output Expressions ............................. 120\nE.27 Refactoring of Matrices ....................................... 121\nE.28 Refactoring of References ..................................... 121\nE.29 Refactoring of For-or-expression Lists ......................... 122\nE.30 Refactoring of Function Arguments ............................ 122\nE.31 Refactoring of Function Call Arguments ....................... 123\nE.32 Refactoring of Function Expressions ......................... 124\nE.33 Refactoring of Simple Expressions ............................ 124\nE.34 Elimination of Redundant Choices ............................. 124\nE.35 Elimination of Names in OpenModelica ......................... 125\nE.36 Elimination of Names in JModelica ............................ 125\nE.37 Refactoring of JModelica ..................................... 125\n### Tables\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Description</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>4.1</td>\n<td>Final Converging and Failing Productions between the Modelica specification and JModelica</td>\n<td>33</td>\n</tr>\n<tr>\n<td>4.2</td>\n<td>Final Converging and Failing Productions between the Modelica specification and OpenModelica</td>\n<td>40</td>\n</tr>\n<tr>\n<td>4.3</td>\n<td>Final Converging and Failing Productions between OpenModelica and JModelica</td>\n<td>44</td>\n</tr>\n<tr>\n<td>5.1</td>\n<td>Summary of the Differences between the Expressions in the Modelica Specification and JModelica</td>\n<td>48</td>\n</tr>\n<tr>\n<td>5.2</td>\n<td>Summary of the Differences between the Expressions in the Modelica Specification and OpenModelica</td>\n<td>48</td>\n</tr>\n<tr>\n<td>5.3</td>\n<td>Summary of the Differences between the Expressions in OpenModelica and JModelica</td>\n<td>48</td>\n</tr>\n<tr>\n<td>5.4</td>\n<td>Overview of the Transformations Used in the Three LCIS</td>\n<td>63</td>\n</tr>\n</tbody>\n</table>\n## Figures\n\n<table>\n<thead>\n<tr>\n<th>Figure</th>\n<th>Description</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2.1</td>\n<td>Parse Tree of the Modelica Specification Expressions</td>\n<td>5</td>\n</tr>\n<tr>\n<td>2.2</td>\n<td>Parse Tree of the JModelica Expressions</td>\n<td>6</td>\n</tr>\n<tr>\n<td>2.3</td>\n<td>Parse Tree of the OpenModelica Expressions</td>\n<td>8</td>\n</tr>\n<tr>\n<td>3.1</td>\n<td>Abstract Convergence Process</td>\n<td>15</td>\n</tr>\n<tr>\n<td>3.2</td>\n<td>Convergence Process of the Example LCI</td>\n<td>21</td>\n</tr>\n<tr>\n<td>5.1</td>\n<td>Parse Tree of the Transformed JModelica Expressions</td>\n<td>50</td>\n</tr>\n<tr>\n<td>5.2</td>\n<td>Parse Tree of the Transformed OpenModelica Expressions</td>\n<td>51</td>\n</tr>\n<tr>\n<td>5.3</td>\n<td>Parse Tree of the Modelica Specification Expressions</td>\n<td>52</td>\n</tr>\n</tbody>\n</table>\nNomenclature\n\n<table>\n<thead>\n<tr>\n<th>Abbreviation</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>BGF</td>\n<td>BNF-like Grammar Format</td>\n</tr>\n<tr>\n<td>BNF</td>\n<td>Backus Naur Form</td>\n</tr>\n<tr>\n<td>DNF</td>\n<td>Disjunctive Normal Form</td>\n</tr>\n<tr>\n<td>EBNF</td>\n<td>Extended Backus Naur Form</td>\n</tr>\n<tr>\n<td>LCF</td>\n<td>LCI Configuration Format</td>\n</tr>\n<tr>\n<td>LCI</td>\n<td>Language Convergence Infrastructure</td>\n</tr>\n<tr>\n<td>SLPS</td>\n<td>Software Language Processing Suite</td>\n</tr>\n<tr>\n<td>XBGF</td>\n<td>Grammar Transformation Language; transformations (X) of grammars in BGF</td>\n</tr>\n</tbody>\n</table>\nChapter 1\n\nIntroduction\n\nModelica, an object-oriented programming language for modeling physical systems, is the outcome of the PhD thesis by Hilding Elmqvist published in 1978 [1]. Almost twenty years later, the ideas presented in the PhD thesis were picked up in an effort to design a language for modeling physical systems. In September 1997, Modelica 1 was published [2]. Three years later, the non-profit organization Modelica Association was founded to manage the development of the Modelica language [3]. Commercial and open-source front-ends started to evolve. JModelica is an open-source platform that handles optimizing, simulating, and analyzing dynamic systems. OpenModelica is a simulation and modeling environment for Modelica.\n\nThe Modelica language specification includes a syntactic description of the language. The front-ends usually work on a grammar ingrained in the respective parser descriptions. With the different descriptions the Modelica language receives, the question arises whether these descriptions model the same language. Working in an area of computer science, you may come across a variety of software artifacts that include grammar knowledge. For Modelica, this grammar knowledge is sourced in parser descriptions and a language specification document. For reasons like interoperability, this knowledge should be consistent. One problem is to establish and maintain the relationship between the grammar knowledge in the different software artifacts.\n\nThe problem we tackle in this thesis is the correspondence between the different Modelica grammar versions. To find an answer to this problem, we compare the grammars. With the help of a suitable tool, we want to establish a relation between the grammars. As the versions, by their own nature, vary, we will need to transform the grammars to align them. Grammar transformations is our means to narrow down the differences between the grammar versions.\n\nThe result of this cycle of transformations and comparisons gives us an answer to the question whether the grammars model the same language. If the process discloses any differences that cannot be resolved, the question then becomes whether the difference is evidence of a contradiction between the two grammars or the case of one grammar being more relaxed than the other. In addition, one might ask what the origins of the difference could have been. In this thesis, we want to answer these questions for an excerpt of three grammar versions of the Modelica language. The grammar versions come from the Modelica language specification and the Modelica implementations JModelica and OpenModelica.\n\nThis thesis follows a road map towards answering the question whether the different Modelica grammar versions model the same language. The road map starts at the foundations of the thesis in Chapter 2. First, we take a closer look at the different Modelica versions in Section 2.1. We introduce the language Modelica and its simulation environments JModelica and OpenModelica.\nand examine how each version presents its grammar. Additionally, we reflect on the grammars’ parse trees and carry out a superficial comparison of the trees. Second, we draw a picture of the current state of the art in comparing grammars and converging languages in Section 2.2. This overview considers the background and motivation of language convergence, the current state, and related work. With the current state, we meet the means to answer our question, the tool Language Convergence Infrastructure. The overview also takes a quick glance at open research questions. From the foundations, we move on to the tool we have chosen to investigate the Modelica grammar versions with in Chapter 3. Its setup, its components, and a simple example are the topics visited within this chapter. Next stop on the road map is the pairwise comparison of the grammar versions using the Language Convergence Infrastructure in Chapter 4. We discuss the grammar transformations applied as well as the results of the comparisons. An evaluation of the outcome of the investigation follows in the subsequent chapter, Chapter 5. It includes an analysis of the results (Section 5.1), a discussion of the transformations used (Section 5.2), and considerations about the Language Convergence Infrastructure as the means to answer our question (Section 5.3). The road map ends at Chapter 6 with the conclusion extended by some thoughts about future work.\nChapter 2\n\nFoundations\n\nIn this chapter, we familiarize ourselves with background information concerning Modelica and its grammar versions as well as with the current state of the art relating language convergence and grammar comparison. We start with the Modelica versions in Section 2.1 and go on to the overview of language convergence afterwards in Section 2.2.\n\n2.1 Modelica Versions\n\nModelica is an object-oriented language for modeling systems, e.g., mechatronic models in robotics or aerospace applications with a large number of subsystems. All parts of a model can be devised in the language. Modelica has a mathematical nature: all components of the model description are mapped to differential, algebraic, and discrete equations.\n\nTo fully utilize Modelica, a simulation environment is required. An environment supports the user in defining Modelica models in graphical user interfaces, which translate a graphical representation into a textual Modelica model. The environment translates the model into a form it can simulate. Finally, it simulates the model and visualizes the results. Of the environments available, two noncommercial, open-source projects are JModelica.org and OpenModelica.\n\nThe information on Modelica, JModelica, and OpenModelica originate from the corresponding user’s guides and language specifications as well as API documentations. For Modelica, the Language Specification document [4] is the source of information. The JModelica knowledge comes from the user’s guide [5] and the API documentation [6]. The insight in OpenModelica stems from the user’s guide [7].\n\nThe remainder of this chapter consists of three sections, each concentrating on one Modelica grammar version, starting with the Modelica specification itself.\n\n2.1.1 Modelica Specification\n\nModelica states the language’s grammar in its Language Specification document. The most recent version is 3.3 but the grammar has not been changed from version 3.2 to its successor. The grammar is expressed in extended Backus Naur Form (EBNF) that is optimized for readability. Syntactic meta symbols exist to indicate a disjunction, a quantity of zero or one, and an iteration of zero or more times. Square brackets denote an optional expression. Curly braces mark an expression to be repeated zero or more times. A vertical bar separates choices from each other. Text in quotation marks is treated as a single token. An example production using these meta\nCHAPTER 2. FOUNDATIONS\n\nsymbols is the following choice of either an optional terminal named “text” or a star expression of a nonterminal named “body”.\n\nhead :\n [ \"text\" ] | { body }\n\nAn excerpt of the grammar, namely, the section “Expressions”, can be found in Appendix A.1. A slight difference exists between the grammar in the language document and in the appendix. In the published version, Modelica keywords are in boldface, a markup lost after copying text from a PDF file. The keywords are reserved and, therefore, may not be used as identifiers. But as part of the grammar, they are terminals and by their nature, treated as a single token. As a consequence, the keywords are not in boldface but in quotation marks in the appendix.\n\nLet us have a quick look at the structure of the grammar fragment in the Appendix. Figure 2.1 depicts the corresponding parse tree. We can see from the figure that the tree consists of two parts, one starting and ending at the node `expression` and one for comments. From the node `expression`, a relatively direct branch leads to the node `primary` after which the tree splits up into several branches of which most lead back to the node `expression`.\n\nAfter the grammar from the Modelica specification has been introduced, we will now take a look at the grammars of the two Modelica implementations, JModelica and OpenModelica.\n\n2.1.2 JModelica\n\nJModelica.org provides a simulation environment for Modelica. Its most recent release claims to support Modelica 3.2. Its grammar is specified through a parser description, which can be found in the JModelica repository1. The parser is generated by Beaver, a parser generator for deterministic context-free languages. Beaver generates LR parsers that parse the input from left to right and construct a rightmost derivation. The input grammar needs to be in EBNF [8]. The generated parser consists of parser-specific code, including error handling procedures. The production heads have a class, the referenced nonterminals can be identified by variable names, and each branch has a return statement. The JModelica parser uses only two syntactic meta symbols for expressing the grammar. Vertical bars separate choices, a question mark denotes an optional expression. Terminals are in uppercase letters. The same example production as in Modelica reads using JModelica meta symbols:\n\nhead :\n TEXT? | body_star?\nbody_star :\n body body_star\n\nJModelica does not use a star expression, therefore, two productions are needed to model this kind of expression. A version of the grammar used in the parser is presented in Appendix A.2. It contains only the productions that model the same expressions as the Modelica expressions and is converted to EBNF for readability.\n\nThe parse tree for the expressions in the JModelica grammar is pictured in Figure 2.2. Again, we have a split tree for expressions and comments. The whole tree appears longer, more nonterminals belong to the tree. From the node `exp`, a direct branch leads to the node `primary`. Similar to the Modelica specification parse tree, most branches originating from the node `primary` return to the node `exp`. For example, the branch originating from the node `access_expression` ends in the same constructs, array subscripts, as the Modelica specification. The nodes in between model some kind of smaller access expression themselves. We may assume that this branch generates the component references from the Modelica specification.\n\n1Parser description within the JModelica repository: https://svn.jmodelica.org/branches/1.9.x/Compiler/ModelicaFrontEnd/src/parser/Modelica.parser\nFigure 2.1: Parse Tree of the Modelica Specification Expressions\nFigure 2.2: Parse Tree of the JModelica Expressions\n2.2. OVERVIEW OF LANGUAGE CONVERGENCE\n\n2.1.3 OpenModelica\n\nOpenModelica also implements the Modelica language and as such provides another simulation environment for Modelica. Its most recent release supports Modelica 3.2. Its parser description displays the grammar underlying the OpenModelica implementation. It is part of the OpenModelica source code. OpenModelica uses ANTLR to generate the parser. ANTLR is also a parser generator for context-free languages that takes grammars in EBNF as input. In contrast to Beaver, ANTLR generates LL parsers that read input from left to right and construct a left-most derivation [9]. The parser-specific code includes return statements, variable names, and instructions that update the abstract syntax tree. The meta symbols in the grammar notation are vertical bars, question marks, and stars, denoting a choice, an optional, and a star expression respectively. Uppercase letters mark the terminals. OpenModelica expresses the simple example production in the following way:\n\nhead : TEXT? | body\n\nAppendix A.3 shows a selection of the parser description, i.e., the expressions, transformed into EBNF.\n\nFor the last grammar, we also survey the parse tree, shown in Figure 2.3. Similar to the previously considered parse trees, one tree starts with the node comment and the other tree has the node expression as the top node. Many of the branches stemming from the node expression route back to the node. The tree illustrates that the node expression calls more nodes than the corresponding node in the other two parse trees. A direct branch leads from the node expression to the node primary as in JModelica. The part after the node primary appears to be less complex compared to JModelica but uses more nodes compared to the Modelica specification. Another notable feature of the OpenModelica tree is that one branch originates from the node expression and bypasses a large portion of the branch that leads to the node primary. This branch is singular in the set of the presented parse trees.\n\nWith the short introduction into each grammar version, we have an idea of the overall concurrency and the immanent differences between the three versions. Next, we give a survey on the current state of language convergence.\n\n2.2 Overview of Language Convergence\n\nThis section focuses on language convergence. More specifically, it concentrates on grammars and the convergence of grammars of the same language but from different sources or dialects. Modelica is a language with different sources for grammar knowledge which we want to converge.\n\nProgramming languages receive multiple descriptions. The grammars that are explicitly or implicitly embodied in these descriptions are ideally equivalent. But considering the vast nature of the sources, the fact that different compilers exist for the same language, or that languages evolve makes it arguable whether the grammars are indeed equivalent. The idea behind language convergence is to check whether these grammars are consistent. Examining consistency is beneficial for various reasons, among them avoiding problems when using different compilers or having correct language documentation. A main contribution to that research area has been made by Zaytsev and his co-authors [10, 11, 12, 13].\n\nThis section has the following structure: In the first subsection, we enlarge on the background and motivation for language convergence. The second subsection contains an overview of the\nFigure 2.3: Parse Tree of the OpenModelica Expressions\ncurrent state of the work in the field and approaches taken to answer the question about consistency. Related work receives attention in the third subsection. An impression of future work and open research questions follows in the second to last subsection before we end this section with a summary and a quick outlook on our further procedure.\n\n2.2.1 Background and Motivation for Language Convergence\n\nAs mentioned before, language knowledge deviates. What languages do and what they may not be able to do, how they look, and what logic they follow can be found in various sources. Language documentation, XML schemas, compiler and parser descriptions, or even actual source code comprise information about the language and how it works. An important ingredient of any programming language is its syntax. A grammar is a description of the syntax. Usually, the grammar is given in Backus Naur Form (BNF) or a variation of it. It is possible to extract grammars from different sources with varying complexity and success. As the grammars have different targets, they may differ from each other though they concern the same language. Furthermore, considering that different compilers exist for one language, grammars extracted from these sources do not naturally match. It is favorable to know about these differences to be able to handle them or to be able to rely on their absence.\n\nGrammars may not only vary because they come from different sources but also on a lower level, from project work. People on the same project use different notations. At one point, the participants might want to ensure that their code is consistent. Within a broader scope, programming languages evolve over time as people around the world work with them, extend, or customize them. Compilers and parsers as well as language documentation have to keep up. A framework checking for differences between current versions, but also between current and previous versions, can help to identify changes.\n\nThe background for language convergence lays mainly in grammar transformations. The research in grammar transformation is vast and deserves an own overview. But to summarize briefly the main issues grammar engineers face, consider\n\n- left recursion,\n- ambiguity of grammars,\n- the question whether transformations preserve the semantics of the grammar, and\n- a high diversity in syntactic notation.\n\nLeft recursion can lead to nontermination of algorithms when applying a top down left to right approach, e.g., during parsing. Many researchers investigate finding efficient solutions to that problem, e.g., [14] and [15]. Basten [16] argues that ambiguities in grammars may be wanted but accidentally introduced ones can be harmful, and proposes a method to find them. Grammar transformations can be categorized by refactoring, construction, and destruction. Refactoring preserves the semantics of a grammar, like renaming a nonterminal or function. Construction and destruction change the behavior of a grammar. Lämmel has built a comprehensive operator suite for grammar transformations, which are tested and documented [17]. The suite presents a valuable resource to other peers as they can rely on tested transformations. The last issue in this list refers to a problem recognized as early as 1977 when Wirth [18] asked in an article: “What can we do about the unnecessary diversity of notation for syntactic definitions?” Although all notations are based on BNF, many different versions exist, e.g., WBNF in [19] and TBNF in [20]. A standardization effort by the ISO has only lead to other variants and not to a unification [21]. In an attempt to tackle the diversity from a different angle, Zaytsev proposed to keep the diversity and employ a meta language [22], named BGF, a BNF-like grammar format. The meta language should build a bridge between different frameworks and syntactic notations.\n\nWork that has preceded the recent work on language convergence include\n• parser generation [23],\n• grammar recovery [24],\n• grammar testing [25], and\n• grammar transformation and adaption [26].\n\nOn a different level, researchers have spent time on the question of equivalence of abstract and concrete syntax. In contrast to language convergence where several sources are considered and checked, the equivalence regarding abstract and concrete syntax addresses various problems. In case a concrete syntax already exists, an abstract syntax must be constructed such that it matches [19]. If both syntaxes exist, a mapping needs to be established between the two syntaxes [27]. Researchers also advocate developing an abstract and a concrete syntax together to ensure consistency [23]. The current approaches do not start with abstract or concrete syntax but on a higher level.\n\n2.2.2 Current State\n\nTo my knowledge, there are currently two main approaches to comparing extensive grammars. One involves a meta language to which the grammars are translated. The other one uses test sets generated from the grammars under investigation. We take a closer look at both of them in this section.\n\nLanguage Convergence Using a Meta Language\n\nNurturing from previous work from his co-author Ralf Lämmel on grammar recovery [24] and adaption [26], Vadim Zaytsev published his work on language convergence [10, 11]. The idea behind his work is to verify the consistency of grammar knowledge encapsulated in all kinds of software artifacts. The tool chain consists of grammar extraction and automated grammar transformations of refactoring and editing until the grammars are syntactically identical. The grammars converge to broader and broader targets leading up to a concrete and an abstract syntax representation. The two syntax representations are ultimately converged to one limit, which itself is an abstract syntax. The grammar transformations form an own language, XBGF. From the transformations applied to the grammars, one can draw conclusions regarding contradictions, extension, inclusion, or equivalence. During extraction, the tool abstracts the grammar and converts it to BGF. The abstracted grammar format allows for simple grammar transformations.\n\nTwo years later, Zaytsev presented a language convergence infrastructure [12], a framework part of the open source project Software Language Processing Suite (SLPS) [28]. SLPS consists of scripts developed for comparison, transformation, benchmarking, validation, extraction, and pretty-printing of grammars. The framework combines a transformer and a comparator. For the process to work, the transformer and the comparator need the grammars in BGF. Extractors are scripts that process a software artifact and produce a BGF grammar. They are language-specific. For several languages, they already exist and are part of the suite. The transformer changes the grammars to make them structurally identical. It takes an XBGF script and a BGF grammar as input and generates a transformed BGF grammar as output by applying the input script to the input grammar. The comparator returns the result of the comparison of the grammar sources. Optional are a validator and a generator. The validator checks the XML files generated in the process of checking language convergence for being well-formed. A generator takes a BGF grammar as an input and produces an XBGF script applicable to that grammar. The script could be used as an input for the transformer.\n\nAs admitted by Zaytsev and Lämmel [10], using BGF implies losing some of the details that are part of other forms of grammars. The tool might miss some minor differences between\nGrammars. Some of these details constitute an own research question, like precedence rules. For example, Bouwers et al. [29] developed a tool for comparing and recovering precedence rules and checking for compatibility. With the use of grammar transformations, their tool builds a common representation for the grammars.\n\n**Grammar Comparison Using Test Sets**\n\nThe authors of the aforementioned approach also published another method in collaboration with Bernd Fischer [13]. In an automated approach, grammars are compared to find evidence supporting a claim for (non-)equivalence. The method compares context-free grammars based on parsing generated test data. It is also part of the project SLPS. The work uses results published by Lämmel on grammar testing [25]. It profits from previous work on grammar recovery [24] and language convergence [10] for grammar recovery.\n\nThe work includes a framework for matching nonterminals. The idea is to test acceptance/rejection of the generated test data and thereby, match nonterminals of two grammars. The method differs from what Barrero et al. [30] did on expansive tree grammars. Their approach, too, aims at identifying equivalent nonterminals and, additionally, reducing them. But they do not compare accept/reject behavior. Instead, they compare tree branches themselves. From the equivalence checking, a theorem follows that indicates that the languages are equivalent if the parse trees for two grammars are equivalent. According to Fischer et al. [13], matching nonterminals is possible for grammars that are not fully equivalent. The result of nonterminal matching can be used as a starting point to converge two grammars by corresponding transformations.\n\nThe testing approach to grammar equivalence is limited in the sense that it may find a counterexample for equivalence. In the case of finding one, the result is clear. But the approach cannot prepare a definite conclusion, only provide evidence, if no counterexample occurs as the problem is undecidable.\n\n### 2.2.3 Related Work\n\nIn this subsection, we take a look at related work. In various settings, researchers and engineers may ask themselves whether the models, programs, or languages they are dealing with are equivalent. We consider a case of equivalence in process models as a representative for work in that research field. Furthermore, we visit the closely related areas grammar recovery, especially grammar inference, and language documentation.\n\n**Equivalence in Models**\n\nGerth et al. [31] examine how to detect equivalence in business process models. They decide to compare models at a semantic level to bypass different syntactic notations. As a means to handle the different models, they define a normal form. They split the models under investigation into fragments, which they normalize. In an automated way, the process models are translated into process model terms. These terms are normalized using a rewriting system and then checked for equivalence. Comparing the fragments allows them to draw a conclusion concerning equivalence and builds a basis for merging the models if wanted.\n\n**Grammar Recovery**\n\nLanguage convergence often involves grammar recovery. In the cases above, grammars have been recovered from various sources and examined for equivalence. But different approaches exist to\nrecover a grammar. The approaches themselves can lead to a unified grammar for at least a\nsubset of sources. One approach is grammar inference.\n\nSaha and Narula [32] have developed a system called Gramin. The system infers a grammar\nfrom sample programs using grammar inference techniques. They develop a backtracking algo-\nrithm that iteratively learns the grammar behind the sample programs. The system can also be\nused to complete a recovered and possibly converged grammar. It can serve as an extension to a\nframework that recovers and converges grammars if completion is needed. Via certain goodness\ncriteria, the system decides which rules to keep and which to drop if they contradict or which\nnew rules to add for completeness. Dubey deals with the question of suitable goodness criteria\nfor grammar rules [33].\n\nLanguage Documentation\n\nAs the grammar invariably differs depending on its purpose, a framework can help in various\nparts. It cannot only check whether the grammars converge as described above, but it can\nalso be used to generate one grammar from the other. Zaytsev claims, the process makes their\n\n2.2.4 Future Work\n\nWork concerning language convergence includes investigating programming languages for con-\nvergence that have not been examined so far. To this end, the set of grammar extractors has to\nbe extended as well. On a lower level, it may be beneficial to incorporate precedence rules either\nby accounting for precedence during abstraction or by first transforming the grammar such that\nprecedence rules are encoded in the grammar.\n\nA topic pure language convergence excludes is what to do with the result. In a smaller scale,\nit is possible to align the different grammars to build a consistent foundation. If the evolution\nof a language is monitored by language convergence, there may be more steps to automate,\nfor example, adapting parsers, compilers, or documentation to accommodate changes in the\ngrammar.\n\nTo look at a completely different approach, it may be worthwhile comparing grammars on a\nsemantic level like the process modelers. Research concerning the idea may already exist but is\nnot part of this overview.\n\n2.2.5 Summary and Further Procedure\n\nIn summary, most research activity in the area of language convergence circles around Zaytsev,\nLämmel, and their affiliates. So far, an operator suite for grammar transformations, frameworks\nfor language convergence, and grammar comparison based on generated test data exist. Future\nwork is manifold concerning new languages to test or refining the existing tool chain.\n\nWe will use Zaytsev’s approach of using a meta language to compare our Modelica sources.\nHis work includes a case study of the programming language Java. The case study involves\nthe convergence of three different versions of the specification and implementation of the Java\nlanguage. The comparison of a specification and an implementation is what we aim at with the\nModelica language. As a result of Zaytsev’s work, an extensive framework for convergence and\ntransformations exists we can utilize and rely on. In the next chapter, we delve into the details\nof this framework for comparing the three Modelica grammar versions.\nChapter 3\n\nLanguage Convergence Infrastructure\n\nThe tool “Language Convergence Infrastructure” (LCI) is our choice to approach the comparison of the different Modelica grammar versions. It helps to identify differences in grammar knowledge of various software artifacts. The Modelica grammar sources are the language documentation and parser descriptions. The method has first been published by Vadim Zaytsev and Ralf Lämmel[10] and is continuously developed further (e.g., see [33], [11], [12], [35]). We already had a brief look at their work concerning language convergence in the previous chapter. Now, we recapitulate some of the information we have gathered during this brief look and inspect the core tool and its components in more detail.\n\nIn contrast to other work in the area of comparing grammars, the developers built a generic tool, not only applicable to certain domains, parser descriptions, or syntax definitions. A grammar engineer can use it to verify the relationship between grammar knowledge from various software artifacts. The tool uses a unified grammar format as a representation for the knowledge, called BGF. The BGF facilitates the analysis of various forms, XML schemas, object models, etc., thus making it flexible. Apart from verifying correspondence between grammars, the tool also allows for version control between grammar versions. While a grammar evolves over time, the tool helps to track the changes or verify a backward compatibility of the latest version of a grammar with its predecessors. The changes we are able to track are limited to those still in the grammars after extraction.\n\nThe outline for this chapter is the following. We start with an overview of the tool in Section 3.1. In Section 3.2, we explain how to set up the tool, including any prerequisites and how to invoke the tool. We continue with a closer look at the infrastructure of the tool, more precisely, the different phases the developers have divided the process into, in Section 3.3. The framework for the grammar transformations is the topic of Section 3.4. We end with a small example of running a LCI in Section 3.5.\n\n3.1 Overview\n\nGrammar convergence is a verification method. The idea is to extract the grammar from software artifacts and transform them until they become syntactically identical.\n\nTo that end, Zaytsev and Lämmel have developed the grammar format BGF. It adopts the expressiveness of an EBNF, but also permits other constructs, including simple types and namespaces. It is expressed in XML. A version of the grammar for BGF, without namespaces and a type system limited to integers and strings, is shown in Appendix B.1. The decision in\nCHAPTER 3. LANGUAGE CONVERGENCE INFRASTRUCTURE\n\nfavor of an own grammar format allows for a neutral representation impartial to any specific\nmodels or semantics.\n\nThe first step in the convergence process is to extract the grammars. A grammar extractor\nis a tool that is most likely defined in the computational framework of the artifact. It parses\nthe source artifact and produces a grammar in BGF. The next step encompasses a grammar\ntransformer and a grammar comparator that take the previously generated grammars as input.\nThe transformer applies grammar transformations and the comparator compares the grammars.\nThis transform-and-compare cycle typically ends when the input grammars become syntactically\nidentical.\n\nThe grammar transformations are part of a framework set up by the developers. The transfor-\nmations form the language XBGF, where X stands for transformation. The framework consists\nof partially automated grammar transformations that refactor or edit grammars. The term\nrefactoring refers to semantics-preserving transformations whereas editing covers non-semantics-\npreserving transformations. The advantage of the framework is that the transformations have\nbeen checked for correctness.\n\nThe grammar convergence framework is publicly available. It includes grammar extractors for\nvarious programming frameworks, the grammar transformation framework, as well as the gram-\nmar comparator for comparing grammars and the transformer for applying transformations from\nthe XBGF framework. A language documentation for the grammar transformation framework\nis also available.\n\n3.2 Setup\n\nThe LCI is part of the SLPS as mentioned before and as such can be downloaded from its\nrepository. A fail-safe way to get all the necessary scripts is to check out the whole suite though\nonly a portion of the files is needed. Checking out the whole project and familiarizing yourself\nwith the project structure has the advantage that all the paths in the scripts that refer to other\nscripts are still valid and need not to be updated.\n\nThe scripts are written in Python to run on a Unix system. For the tool to work, a specific\nProlog parser is needed, SWI Prolog. At the end of the LCI, diagrams of the convergence\nprocess are generated, which are set in Dot. If the diagrams should be converted into pdf files\nautomatically, a program to handle the diagrams must be installed. Not having such a program\ninstalled, however, will not prevent the tool from working.\n\nFor the tool to properly function, it might be necessary to exchange a line in two scripts. These\nscripts are lci.py and lciConfig.py, located in the SLPS at topics/convergence/lci. Both\nscripts include the line from elementtree import ElementTree. Depending on the structure\nof the XML installation in the operating system, this line needs to be changed into the expression\nfrom xml.etree import ElementTree.\n\nThe tool is invoked by the following line:\n\n$ ./lci <input>.lcf arch\n\nThe first argument is the configuration file that makes the paths, sources, scripts, and transfor-\nmations known to the LCI. The configuration file has to be in LCI Configuration Format (LCF).\nLCF is a configurational domain specific language used by the LCI. The LCF file is a XML\ndocument specifying where the scripts, the sources, and transformation files are located. The\ngrammar of the LCF is in EBNF with selectors. For example, the selector a refers to a particular\noccurrence of a nonterminal b by writing a::b. The built-in symbols of the LCF are string\n\n\\footnote{SLPS repository: https://github.com/grammarware/slps}\n3.3 LCI Process\n\nFor any string, $xstring$ for a macro expanded string, $id$ for a unique identifier, and $refid$ as a reference to an $id$. Appendix C.1 shows the complete grammar. According to the grammar, the scenario needs at least one source and one target, a transformer to apply transformations, and a comparator to compare the sources if there is more than one source. The second argument specifies the name under which the diagrams are saved at the end of the program run.\n\nThe comparison executed by LCI is trivial. It is restricted to string comparison supplemented by a handful of normalizing rules. Before comparing the input grammars, the script normalizes the grammars by eliminating duplicate choices, dissolving sequences of sequences or choices, and handling empty elements. The normalization is also performed after the application of transformations. The single productions with the heads and bodies are identifiable within the BGF by a script. The script then checks whether matching heads exist and if they do, whether the bodies agree. Non-matching heads are exclusive nonterminals for the corresponding grammar and mean a nominal mismatch. Matching heads with diverging bodies are so-called structural mismatches. The command line output keeps up with the progress of the process and the success of each step along the way. The tool produces a result file that lists the common nonterminals with different definitions.\n\nThe LCI invokes the comparator script to compare the input grammars. Calling the comparator script directly with the two input grammars in BGF, a more detailed output is given. Additionally, the exclusive, defined nonterminals are listed as well as the colliding production bodies. The production bodies are given in prefix notation with a semicolon denoting a choice, a comma specifying a sequence, a star, plus, or question mark describing a star, plus, or optional expression, respectively, and the letters ‘n’ and ‘t’ characterizing a non-/terminal. The output helps to identify transformations to align the grammars in a stepwise manner.\n\nWe proceed with the LCI process, i.e., the inner structure of the LCI and a guideline to the transformation programming.\n\n### Figure 3.1: Abstract Convergence Process\n\n\n\nSource grammar 1\n\nTransformation\n\nSource grammar 2\n\nTransformation\n\nTarget grammar\n\nIf two grammars are under investigation, an initial comparison of the grammars is reasonable. Running the script at the beginning reveals the overall differences between the given sources. After the initial run of the LCI, the grammar engineer can start to program grammar transformations to align the sources. The transformations are directed towards a target, a limit. In a scenario where two grammar sources belong to a target, one source is usually determined to be the objective to be reached. The other source is subject to transformations, which transform the source into the objective.\n\nFigure 3.1 illustrates the abstract process of language convergence. Two source grammars are transformed to meet the target grammar, the common denominator between the two grammars. The target grammar can be a source grammar in a new transformation process, which turns the\nCHAPTER 3. LANGUAGE CONVERGENCE INFRASTRUCTURE\n\ntarget into an intermediate target. By stepwise converging the different grammar sources in a compare/transform cycle, all grammar sources are transformed to the grammar limit, the final target.\n\nTo provide more structure to the convergence process, five phases form the process of which each but the first is optional, namely\n\n- **extraction** of grammars from different sources/artifacts,\n- **convergence preparation**, e.g., fixing known errors,\n- **nominal matching**, e.g., rename, inline, unchain,\n- **structural matching**, i.e., semantics-preserving refactorings, and\n- **resolution** (extension, relaxation, correction).\n\nFrom one phase to the next, the number of differences between the grammars must decrease. The first two phases are executed once per source.\n\nIn the first phase, a script is responsible to extract the grammar from its source and transform it into the internal representation format BGF. For each grammar source, a script must be specified. The LCI saves the extracted grammars at certain paths to be able to fall back on them whenever an error occurs or the process restarts. In the next phase, a script can correct known or obvious errors. During nominal matching, any renaming, (un)folding, or other semantics-preserving transformation applies to dissolve nominal mismatches. The phase is followed by structural matching, which includes any semantics-preserving grammar transformations that align productions with structural mismatches. The last phase, resolution, refers to grammar transformations that are not semantics-preserving. They can be semantics-increasing or -decreasing. The phase is divided into three parts, extension, relaxation, and correction. During extension, grammar differences are resolved that can be explained by language evolution. Relaxation addresses the issue that grammars used for implementation are usually more permissive than grammars optimized for readability. The last part centers around the remaining differences. These differences are not meant to be and handled as a newly found bug and therefore, need correction.\n\nOnly after all semantics-preserving transformations are exploited and the sources cannot be aligned further, the grammar engineer moves on to the resolution phase. The grammar transformations programmed during this phase should be considered carefully, as they alter the scope of the grammar. Moreover, no zig zag transformations should be done, meaning that one transformation increases the semantics while another transformation decreases the semantics. The transformations might cancel each other out and the statement about a relation between the source grammars can become more vague.\n\nThe transformations programmed for the LCI are in XBGF, the grammar transformation language set up specifically for this purpose. XBGF is XML-based as well. The transformer takes a transformation written in XBGF as an input as well as the grammar to which the transformation should be applied and generates the transformed grammar. We familiarize ourselves with XBGF in the upcoming section.\n\n3.4 Programmable Grammar Transformations\n\nThe transformation language XBGF provides 49 transformation operators. They are categorized by their effect on the semantics of an expression, i.e., semantics-preserving, -increasing, and -decreasing. Some of them are fully automatized, others need the specific expression that is to be transformed and what it should be transformed into. Then, the transformer searches for the specific expression and replaces it with the new one. For the comparison of the Modelica versions, we will predominantly use the following transformation operators:\n3.5. EXAMPLE LCI\n\nListing 3.1: Example Productions\n\n[Modelica Specification] subscript :\n\";:\" | expression\n\n[JModelica] subscript :\n\"COLON\" | exp\n\n- renameT, renameN\n- inline, extract\n- massage\n- factor, distribute\n- vertical, deyaccify\n\nThe first item refers to renaming terminals and nonterminals. Inlining a production replaces every instance of the nonterminal with its definition and eliminates the production. If we extract a production, a new nonterminal is specified with its defining production body. Every occurrence of the production body is then replaced by the new nonterminal. The operator massage allows rewriting expressions according to certain equivalence rules, like a double optional equals an optional or an optional equals a choice of an epsilon and the option, as well as distributivity laws. The operator distribute dissolves inner choices by distributing the sequences over the inner choices. The operator factor pulls an identical expression out of choices. The next item refers to a transformation that breaks up all top-level choices into individual productions. In the cases of the operators extract, massage, and factor, the scope can be limited from the whole grammar to a nonterminal or one production of a nonterminal. The argument of the transformation operators distribute and vertical represents the scope of the transformation. Deyaccification refers to procedures where recursive definitions are converted to iterative definitions. The transformer checks whether the grammar productions for the specified nonterminal fulfills a yaccified pattern. If true, the expression is replaced using regular expressions. The transformation can only be applied to two vertical productions of one nonterminal. The demand for vertical productions leads to the transformation often occurring in combination with the transformation vertical.\n\nThe last section before the application of LCI to Modelica deals with a simple example of the LCI. The example is taken from the Modelica grammar versions.\n\n3.5 Example LCI\n\nAfter concentrating on the structure and the ingredients of the LCI, a small example shows a practical application. We consider an expression from the Modelica specification and from JModelica, which presumably model the same construct, a subscript; see Listing 3.1. The JModelica production is devoid of the parser-specific code. For the time being, we convert the two grammar excerpts by hand into BGF. Doing so allows us to become familiar with the structure of a BGF. In both cases, the grammar consists of one production with the head nonterminal subscript and a body expression that is a choice of two expressions, one a terminal, the other one a nonterminal. This description of the grammar excerpts directly translates into the BGF description. Each grammar consists of one production with a nonterminal and an expression. The expression comprises an XML tag choice. Two expressions compose the choice, one being a terminal, one a nonterminal. With the help of the BGF grammar in Appendix B.1 we construct the BGFs by deriving the description and writing XML tags for each label or nonterminal we derive. The resulting BGFs are shown in Appendix B.2.\nWe start introducing the different components of the initial LCF for the LCI of the two subscript expressions. The following lines open and close a LCF file.\n\n```xml\n```\n\nThe first component are shortcuts.\n\n```xml\n<shortcut>\n <name>impl</name>\n <expansion>../</expansion>\n</shortcut>\n<shortcut>\n <name>s src s</name>\n <expansion><expand>impl</expand>/srcs</expansion>\n</shortcut>\n<shortcut>\n <name>extraction</name>\n <expansion><expand>impl</expand>/extraction</expansion>\n</shortcut>\n<shortcut>\n <name>tools</name>\n <expansion>../../slps-master/shared/tools</expansion>\n</shortcut>\n```\n\nThe shortcuts define paths to different positions in the file system where the scripts and grammars are stored. They facilitate navigating through the system. The first shortcut, for instance, names the path to the root directory from the point where the LCF is stored.\n\nThe next part defines the tools for the process.\n\n```xml\n<tools>\n <transformer>\n <grammar><expand>tools</expand>/xbgf</grammar>\n </transformer>\n <comparator>\n <grammar><expand>tools</expand>/gdt</grammar>\n </comparator>\n</tools>\n```\n\nFor the process to work, a transformer and a comparator are mandatory. They are specified by their path.\n\nThe next part are the grammar sources, which need at least a name and a grammar source.\n\n```xml\n<source>\n <name>leaf−expr−j</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/j2bgf <expand>srcs</expand>/jmod/leaf−expr−j.txt\n </extraction>\n </grammar>\n</source>\n<source>\n <name>leaf−expr−m</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/m2bgf <expand>srcs</expand>/mmod/leaf−expr−m.txt\n </extraction>\n </grammar>\n</source>\n```\nIn the example, there are two different sources, each having a unique and descriptive name. The grammar source is specified by an extractor and the source file. For the example, the extractor does nothing but copying the source as the source already is in BGF. We do so because the LCI requires an extractor and with that also saves the newly generated BGF files under certain paths. Writing a script that creates a new file to which it copies the contents of the other file allows the LCI to save that file under the path the LCI needs.\n\nThe final part is the target.\n\n```xml\n<target>\n <name>node</name>\n <branch>\n <input>leaf−expr−j</input>\n </branch>\n <branch>\n <input>leaf−expr−m</input>\n </branch>\n</target>\n```\n\nA target needs an identifier and at least one branch. A branch has an input, i.e., a grammar source or intermediate target. Optionally, a branch has phases in which given transformations are applied to the input. In the example, the target under the name `node` has two branches with the two grammars as inputs. No transformations are given as we do the first comparison of the sources. Listing C.2 in Appendix C.2 shows the LCF as a whole.\n\nIf we invoke the LCI with the LCF for the subscripts, we get the following output.\n\n```\nRead 5 shortcuts, 2+0 tools, 1 targets, 2 sources, LCF is fine. \n[ PASS ] Extracted a newer version of lead−expr−j.bgf. \n[ PASS ] Extracted a newer version of lead−expr−m.bgf \n[ PASS ] Extraction finished. \n[ FAIL ] Mismatch in target node: leaf−expr−j.bgf differs from leaf−expr−m.bgf \n[ PASS ] Target node reached as leaf−expr−j.bgf \nGrammar convergence phase finished. \n------ \n[ WARN ] No testing performed. \n[ WARN ] Detailed diagram not generated \n[ PASS ] Diagram generation completed. \n```\n\nThe first line is a status line about the LCF, telling us that the LCI encountered two tools, which are the comparator and the transformer, one target, and two sources. The next three lines show that the grammar sources have been extracted. Even if the extraction is executed the first time, the LCI states in its output that it extracted newer versions of the grammars. The following line reveals the results of the comparison of the two sources. One branch is then saved as the target. The convergence phase is complete with the saving of a target. The last three lines do not have to concern us. The two warnings turn up because, first, we do not specify test cases, and second, part of the diagram generation is turned off by default.\n\nIf we call the comparator script directly with the two sources as input, we get the following output.\n\n```\nNormalizing mod/leaf−expr−m.bgf. \nNormalizing jmod/leaf−expr−j.bgf. \nDiffering mod/leaf−expr−m.bgf and jmod/leaf−expr−j.bgf. \n Names of defined nonterminals agree. \n Comparisons per (common) nonterminal: \n - Fail (1/1): subscript. \n - []::(t();n(expression)) \n vs. \n - []::(t(COMMA),n(exp)) \n - Roots agree. \n```\nWe now have one definition below the other of each colliding nonterminal, in our example just one. We can see that we have to rename the terminal and the nonterminal. Renaming terminals and nonterminals follows the same pattern. We have to specify the name of the term we want to rename and to what it should be renamed. When the transformer applies the transformation, every occurrence of the term is replaced by the new one. The pretty-printed versions of the example transformations are `renameT(\"COLON\", \";\");` and `renameN(exp, expression);`. The XML description is straightforward. We indicate that we want the transformation `rename` followed by either a terminal or a nonterminal tag depending on what we want rename. Within this tag, we specify from what we want to change the term to. The resulting XML including the start and end tags looks like the following.\n\n```\n<xbgf:sequence xmlns:xbgf=\"http://planet-sl.org/xbgf\">\n <xbgf:rename>\n <terminal>\n <from>COLON</from>\n <to>:</to>\n </terminal>\n </xbgf:rename>\n <xbgf:rename>\n <nonterminal>\n <from>exp</from>\n <to>expression</to>\n </nonterminal>\n </xbgf:rename>\n</xbgf:sequence>\n```\n\nNext, we update the target in our LCF by a reference to this transformation. The target is then defined via the following description.\n\n```\n<target>\n <name>node</name>\n <branch>\n <input>leaf-expr-j</input>\n <structural-matching>\n <perform>rename-j-leaf</perform>\n </structural-matching>\n </branch>\n</target>\n```\n\nThe updated LCF can be seen in Listing C.3 in Appendix C.2. If we run the LCI again, we receive the following output.\n\n```\nRead 5 shortcuts, 2+0 tools, 1 actions, 1 targets, 2 sources, LCF is fine.\n[PASS] Extraction finished.\n[PASS] Applied structural matching rename-j-leaf.xbgf to leaf-expr-j.bgf\n[PASS] Postextraction and synchronization finished for target node.\n[PASS] Branch finished as leaf-expr-j.rename.bgf\n[PASS] Target node reached as leaf-expr-j.rename.bgf\n```\n\n---\n\nGrammar convergence phase finished.\n\n```\n[WARN] No testing performed.\n[WARN] Detailed diagram not generated\n[PASS] Diagram generation completed.\n```\n\nThe LCI has found one action, the XBGF transformation, in the LCF. In comparison to the previous LCI run, one line provides the status of the extraction phase. With the first LCI run, the sources have been extracted and the files saved. The LCI can go back to these files and does not need to call the extractor again. The output contains a line informing us about the successful\napplication of the transformation. The next two lines brief us on the status of the comparison, which was successful. The remainder of the output is identical to the aforementioned output.\n\nThe convergence process is visualized in Figure 3.2. The figure belongs to the diagrams generated by the LCI. The last line of the output informed us about the successful completion of the diagram generation. If the input branches do not meet the target, the LCI generates a diagram where the target is typeset in a red color.\n\nWith the example, we have seen how the LCI works in small scale. In the next chapter, we tackle a larger set of grammar productions as the subjects of the LCI.\nChapter 4\n\nLCI for Modelica\n\nIn this chapter, we use the LCI to compare our three Modelica grammar versions. The purpose of this chapter is twofold. One, we will see how to use the LCI to compare and transform the three grammar versions. Two, we collect evidence for a statement concerning the relation between the grammar versions and their equivalence.\n\nThe outline of the chapter is the following. We start with a brief look at preceding choices about how to set up the LCI in Section 4.1. The choices include what parts of the LCI we use and what the grammar is we choose to transform the other grammar towards. The next section, Section 4.2, centers around the extraction of the three grammar versions and conversion into BGF. We continue with a description of the work on the pairwise comparison of the grammar versions. Section 4.3 describes the comparison of the Modelica specification with JModelica, Section 4.4 the comparison of the specification with OpenModelica, and Section 4.5 the comparison of OpenModelica with JModelica. The three sections all follow the same structure of an initial comparison, the grammar transformations, and a look at the final results, with a summary at the end. We will see that actually the grammar versions do not converge but exhibit differences that do not lead to a distinct relation between the versions. The first part, the Modelica specification vs. JModelica, receives a more detailed explanation to clarify the process. The other two parts will be handled in a more condensed way. At the end of this chapter, we briefly summarize our work (Section 4.6). An evaluation of the results will take place in the next chapter, Chapter 5.\n\n4.1 Preliminaries\n\nFor the comparison of the Modelica grammars, we use a “core” LCI, specifying only a comparator and a transformer. The three grammar versions are the sources within the LCI. For this thesis, we restrict the grammars to expressions. Starting point for deciding which productions to consider is the Modelica specification. We include the productions in the section “Expressions” in the Modelica specification. The definitions of referenced nonterminals outside this section are ignored. We compare two sources at a time, thus, the three pairings separately. We stop after the application of semantics-preserving transformations. We do not move on to the last phase of resolution as we are interested in the differences and not a full language convergence. The objective of the convergence process is the Modelica specification in the first two cases as it represents the original grammar as published by its creators. For the comparison of the grammar versions from OpenModelica and JModelica, the OpenModelica grammar becomes the target. The choice is fairly arbitrary, the motive in this case being that OpenModelica’s grammar structure resembles the one of the Modelica specification more than JModelica’s grammar structure.\nWith the sources and the target as well as the comparator and the transformer, we have the main components for the LCI. The next step in the work process is to write the scripts we need to transform the sources into BGF, which is subject of the upcoming section.\n\n4.2 Grammar Extractors\n\nFor each grammar version, we need a script to transform the grammar from its original form into BGF. Doing the transformation by hand is very cumbersome as the representation in BGF is rather complex and long even with only part of the grammar. The scripts are written in Python as are most of the scripts in the LCI. The scripts handle the expressions of the respective grammars and any other simple input without nested choices or highly nested star, plus, or optional expressions. In all three cases, a preprocessing takes place to prepare the grammars for transformation into BGF. The preprocessing includes deleting the parser-specific code and printing each production in one line. The main transformation script goes through each line of the file and prints the production accordingly. The preprocessing script takes the original grammar version as an input, and the transformation script then takes the file generated by the preprocessing script.\n\nThe body of this section consists of a subsection for each grammar version where we take a closer look at the scripts.\n\n4.2.1 Modelica Specification\n\nThe Modelica grammar is available in its language specification document. The section for expressions is copied into a text file, which serves as the input for the preprocessing script. The productions have a similar structure, which is used as a guideline to build the script. Terminals are enclosed by quotation marks to distinguish them from the nonterminals. As the Modelica keywords are marked in bold in the document, a property that is lost during copying, we need the script to mark them with quotation marks as well. In most cases, the production head is in one line and the body, depending on its length, in the following lines. The head and the body are further separated by a colon and the body is indented. The first production of the section “Expressions” in the Modelica specification grammar showcases this behavior:\n\n```\nexpression :\n simple_expression\n | \"if\" expression \"then\" expression { \"elsif\" expression \"then\" expression } \"else\" expression\n```\n\nThe preprocessing script reads each line of the text file. If the line starts with a non-whitespace character, a new production starts. The production head, the first word of such a line, is printed into the new text file. The colon character is not printed in the new file. If the line ends there, the script goes on to the next line. If the line continues, part of the production body is in the same line as the head. Then, the line is split after the colon, and the latter part is saved for the printing of the production body. If the line starts with a whitespace character, we save the lines in a list until the script encounters another line with a non-whitespace character, which means that the production body is complete. Before handling the new production, the body is printed into the new file. After preprocessing, the production above looks like the following:\n\n```\nexpression simple_expression | \"if\" expression \"then\" expression { \"elsif\" expression \"then\" expression } \"else\" expression\n```\n\nThe procedure repeats until the script reaches the end of the file. Then, the last production is printed and the files are closed.\nThe transformation script prints the headers of the XML file and then goes through each line of the file and prints the productions. The first word is the production head, the remainder of the line the body. The head is printed, and a function to print the body is called. According to the length and the types of markers like a vertical bar for choices, curly braces for star expressions, and square brackets for optional expressions, the respective XML expressions are printed and further functions are called to print the inner parts or choices. The printing and calling of functions continues until we are left with single terms, i.e., terminals and nonterminals, to print. At the end, the concluding expressions for the file are printed and the files closed.\n\nBoth scripts are combined in an executable that handles the input and output files. The executable needs the input grammar and the output file for the BGF at the end as input arguments. The executable is also the one specified in the LCF file as the extractor. The LCI takes care of feeding the executable with the input.\n\n4.2.2 JModelica\n\nJModelica specifies the grammar in the parser description. As we restrict the Modelica grammar to the expressions section, we take only the corresponding productions from the JModelica grammar. To transform the grammar into BGF, we need to delete the parts that are parser-specific and do not carry any information concerning the grammar. For JModelica, this parser-specific code is enclosed by {: and :}. The preprocessing script strips the grammar off these parts. The script also deletes class and variable names. The end of a production is marked by a single semicolon in a line. The corresponding production to the production in the previous subsection reads in JModelica:\n\n\\[\n\\begin{align*}\n\\text{Exp exp} &= \\text{simple_expression} \\{ : \\text{return simple_expression; :} \\\\\n& \\mid \\text{if_exp} \\quad \\{ : \\text{return if_exp; :} \\\\\n& ;\n\\end{align*}\n\\]\n\nThe script follows the same procedure as the one for the Modelica specification. It goes through each line of the file. If the line starts with a non-whitespace character, a new production starts. As we have class names, the nonterminal that is the production head is the second word in the line. The body of the production is appended to a list line by line until the end symbol is read. While appending the production body, the parser-specific parts and variable names are omitted. The body is printed in a line with the production head. The script converts the production given above into the following line:\n\n\\[\n\\begin{align*}\n\\text{exp} \\text{ simple_expression} \\mid \\text{if_exp}\n\\end{align*}\n\\]\n\nOne property of the JModelica grammar is that no nested choices, star, or plus expressions exist. Additionally, optional expressions are only expressions with one term, not sequences. Therefore, the script can go through each line of the file, print the first word of the line as the production head and call a function for the rest of the line. If there is a vertical bar in the line, we have a choice and can print the needed XML expressions. For each choice, another function is called, which also handles the body if no choice is at hand. After this point, each word can be handled as a single term testing whether it ends with a question mark for an optional expression or is uppercase for terminals. Else, we have a simple nonterminal. For each case, the function prints the needed XML expressions. The script also prints the starting and ending expressions for the XML format. The result is the JModelica grammar in BGF format.\n\nAs with the Modelica specification, an executable manages the calling of the scripts with the correct inputs and represents the extractor in the LCF file.\n4.2.3 OpenModelica\n\nThe OpenModelica grammar is embedded in the parser description generated by ANTLR. Again, some preprocessing is necessary to delete the parser-specific code. The parser-specific code is either marked by curly braces or a return statement beginning directly after the production head and optionally followed by a declaration part introduced with @. The return statement closes with a colon, which marks the end of the head and the beginning of the body of the production. As with JModelica, the parser includes variable names that need to be deleted and the production body must be accumulated to be printed in one line. The script does the preprocessing in the same fashion as the other two scripts, producing a text file with one production per line and the head as the first word. The production\n\n```plaintext\nexpression returns [ void* ast ]:\n ( e=if_expression { ast = e; }\n | e=simple_expression { ast = e; }\n | e=code_expression { ast = e; }\n | e=part_eval_function_expression { ast = e; }\n | e=match_expression { ast = e; }\n )\n```\n\ntransforms to the following line:\n\n```plaintext\nexpression if_expression | simple_expression | code_expression | part_eval_function_expression | match_expression\n```\n\nThe transformation script resembles the one for the Modelica specification as the OpenModelica grammar is similar in structure to the specification grammar. The vertical bar represents a choice. Optional expressions are marked by a question mark, star expressions by a star. Terminal nodes are identifiable by checking whether a term is uppercase. For a description of the approach to print the grammar in BGF, please refer to the Modelica specification extractor description in Section 4.2.1. The same holds for the executable that is referenced in the LCF file as the extractor.\n\nWith the extractors for the grammar sources, we can proceed and start to compare the grammar versions. We will start with the comparison of the Modelica specification with JModelica.\n\n4.3 Modelica Specification vs. JModelica\n\nThe two grammars subject to comparison are the Modelica specification and JModelica. The first step in this section is to write the LCF file to start the comparison with. Without any transformations specified, the LCI outputs the differences between the two grammars. After the first run of the LCI, we start to analyze the differences and program transformations to align the grammars. After no semantics-preserving transformations can be applied anymore to further dissolve any differences, we investigate the remaining differences. The differences involve the logical and arithmetic expressions, names and single function arguments, which are more relaxed in JModelica. The constructs where the Modelica specification is more permissive are the component references, the primaries, more precisely, the built-in functions `initial()` and `der(...)`, the output expression lists, and the list that is allowed before an expression involving the keyword `for`.\n\nEach of the following subsections delves into one of these working steps. First, we take a look at the initial LCI run, with its LCF and the output in Subsection 4.3.1. Next, we go through the transformations that are targeted towards resolving the differences identified in Subsection 4.3.2. Last, we analyze the output of the LCI with the transformations of the preceding subsection specified in the LCF file and thus, applied to the grammar in Subsection 4.3.3.\n4.3.1 Initial LCI\n\nAs the LCI takes a LCF as an input, we need to write a LCF file specifying the paths to the folders where the different scripts can be found, the paths to the sources, and the target. Listing C.4 in Appendix C.3 shows the initial LCF file. The LCF from the small example in the previous chapter (Section 3.5) has been modified to address the new sources and the new target. The sources are the Modelica specification and JModelica grammar text files with a fitting reference name. The extractors are the ones presented in the previous section. The target gets a name and the input branches, which are the reference names for the two grammar sources. As mentioned before, no transformations appear at this stage, which means that the LCF is complete.\n\nRunning the LCI with this LCF file as input delivers an output that says that differences between the two grammars exist and that the common target could not be reached. The result file tells us that eleven shared nonterminals have different production bodies. If we call the comparator script alone, we get a more detailed output that contrasts the colliding definitions. The comparator output also names the nonterminals that are used exclusively by one grammar. Listing D.1 in Appendix D.1 shows the comparator output. The output reveals that the terminals all differ as JModelica uses uppercase letters and writes out symbols. That is a starting point for transformations, renaming the terminals to make them identical. The same holds for some nonterminals where it is obvious that they are meant to be identical, e.g., expression and exp. For the other differences, we have to take a look at each and may take other productions into consideration that are not part of the fail note. Stepwise, we work ourselves through the list of failed productions and try to include the nonterminals not shared by now.\n\nThe next subsection examines the transformations applied to the JModelica grammar.\n\n4.3.2 Transformations\n\nThis subsection examines the transformations applied to JModelica. The transformations form two groups. To the first group belong the transformations where the productions actually converge. The second group consists of transformations that do not lead to identical productions. But in order to narrow down the differences or to even be able to identify the differences, we program the transformations nonetheless. We will first go through the transformations where the targeted productions converge and then through the transformations of diverging productions. Appendix E.1 lists all transformations that are applied to JModelica in the process of comparing JModelica and the Modelica specification.\n\nRenaming Terminals and Nonterminals\n\nWe have visited the renaming of terminals and nonterminals in the LCI example in Section 3.5. We do the same with the Modelica specification and JModelica expressions as sources. We gather the differing terminals and nonterminals that need to be renamed to nominally match and program the corresponding transformations. The renaming leads to the productions annotation and subscript to become identical. Later in the process, additional renamings of nonterminals will take place as in some cases, it is not obvious from the beginning which the corresponding Modelica specification nonterminal is to which the JModelica nonterminal needs to be renamed.\n\nSubscripts\n\nThe first two fail notes in the output list relate to the production array_subscripts. The JModelica production uses another production in this context, namely subscript_list. We transform the JModelica production such that it becomes identical to the Modelica production.\nFirst, we deyaccify the production \\texttt{subscript\\_list} to strip the production of the recursion and second, inline the production \\texttt{subscript\\_list}. The transformations change the productions in the following way:\n\n\\begin{verbatim}\nsubscript_list : subscript | subscript_list \",\" subscript\n// vertical( in subscript_list ); deyaccify(subscript_list);\n\\Rightarrow subscript_list : subscript ( \",\" subscript )\narray\\_subscripts : [\" subscript\\_list \"]\n// inline(subscript_list);\n\\Rightarrow array\\_subscripts : \"[\" subscript ( \",\" subscript )\"]\"\n\\end{verbatim}\n\nThe part after the two slashes lists the pretty-printed transformation applied whose result is shown in the next line. The last line equals the Modelica definition. The transformations, \\texttt{deyaccify}, \\texttt{inline}, and \\texttt{vertical}, which is needed for \\texttt{deyaccify} to work, are automated transformations, which are handled by the framework and only need the nonterminal to be specified to which the action should be applied.\n\n\\textbf{Expressions}\n\nGoing on to the next fail note, we see that the Modelica specification defines an expression via a simple expression or a sequence of terminals and nonterminals generating an if expression. The JModelica production calls for another nonterminal, \\texttt{if\\_exp}. If we consult the productions \\texttt{if\\_exp} and the referenced production \\texttt{elseif\\_exp}, we can see that the same transformations as for aligning the subscripts apply to align the production.\n\n\\textbf{Simple Expressions}\n\nThe previous production referenced the production \\texttt{simple\\_expression}, which is also subject of the next fail note in the output list. The difference between the two colliding productions is that one uses choices to express three different possibilities of production whereas the other has a nested optional expression. We can turn the first into the latter by factoring out the nonterminal \\texttt{logical\\_expression} in each choice. The JModelica version reads, with \\texttt{l\\_e} abbreviating the nonterminal \\texttt{logical\\_expression}:\n\n\\begin{verbatim}\nl\\_e | l\\_e \":\" l\\_e | l\\_e \"::\" l\\_e\n\\end{verbatim}\n\nA sequence of the nonterminal \\texttt{logical\\_expression} with an inner choice results from the transformation \\texttt{factor}; the inner choice consists of an epsilon expression and the other two choices minus the nonterminal \\texttt{logical\\_expression} in each choice. The JModelica version reads, with \\texttt{l\\_e} abbreviating the nonterminal \\texttt{logical\\_expression}:\n\n\\begin{verbatim}\nl\\_e ( \\epsilon | \":\" l\\_e | \"::\" l\\_e \"::\" l\\_e )\n\\end{verbatim}\n\nAn epsilon as a choice can be used to transform the rest of the choice into an optional expression.\n\n\\begin{verbatim}\nl\\_e ( \"::\" l\\_e | \"::\" l\\_e \"::\" l\\_e )\n\\end{verbatim}\n\nNow, we have formed the outer optional of the nested expression. The inner part of the optional expression needs to form a sequence with the beginning \"::\" \\texttt{logical\\_expression} and the ending of an inner optional with \"::\" \\texttt{logical\\_expression} again. If we apply the same transformations as before, \\texttt{factor} and \\texttt{massage}, we achieve the sequence. We factor out the identical beginning, \"::\" \\texttt{logical\\_expression}, and transform the choice with an epsilon expression into an optional.\n\n\\begin{verbatim}\nl\\_e ( \"::\" l\\_e ( \\epsilon | \"::\" l\\_e ) )\nl\\_e ( \"::\" l\\_e ( \"::\" l\\_e ) )\n\\end{verbatim}\n\nThe productions are now identical.\n\nThe transformations used for aligning the production \\texttt{simple\\_expression} are not fully automated. Not fully automated transformation require specification of the part that should be\ntransformed and the transformed part. Given this information, the transformer script searches for the part to be transformed and replaces it with the new part. Of course, the transformer checks whether the transformation follows the rules for the intended transformation to secure correctness within the transformation process.\n\nRelations\n\nFor the definitions of the nonterminal relation to align, a transformation not used so far is applicable, extract. As we can easily see, JModelica has six choices where a nonterminal arithmetic_expression resides in the first and the last position and a different relational operator in the middle. Factoring out the nonterminals at the beginning and the end results into an inner choice of the different relational operators. The aforementioned transformation extracts the inner choice as the body of a new production with the head rel_op. After the extraction, another factorization and a massaging transformation is necessary to completely converge the productions relation.\n\nNamed Arguments\n\nThe Modelica specification defines named arguments by the following expression:\n\n\\[\n\\text{named_arguments : named_argument (\"\",\" named_arguments )}?\n\\]\n\nIn order to transform the JModelica definition into the one given above, we need to make a detour first. If we factor out the nonterminal named_argument and massage the new production, we will end up with the reversed production of Modelica. The optional part would come first with a recursive call and a following comma terminal, second the mandatory nonterminal named_argument. To fix the reverse order, we first deyaccify the production, massage it according to the distributivity laws for star expressions, and then yaccify it again. The result of this series of transformations is that the second choice is in reverse order. If we factor and massage the definition now, we have aligned the two productions perfectly.\n\nThe referenced nonterminal named_argument needs two transformations for convergence, inline(named_argument_id); and renameN(function_arg_exp, function_argument);\n\nThe actual XBGF file handling the conversion of named arguments consists of the following pretty-printed transformations.\n\n```\nvertical( in named_arguments );\ndeyaccify(named_arguments);\nmassage(\n named_argument (\"\",\" named_argument\")*,\n (named_argument \",\")* named_argument);\nyaccify(\n named_arguments:\n named_argument\n named_arguments:\n named_argument \",\" named_arguments\n);\nhorizontal( in named_arguments );\nfactor(\n (named_argument | (named_argument \",\" named_arguments)),\n named_argument (EPSILON | (\"\",\" named_arguments)));\nmassage(\n (EPSILON | (\"\",\" named_arguments)),\n (\"\",\" named_arguments)?);\ninline(named_argument_id);\nrenameN(function_argument_exp, function_argument);\n```\nComments\n\nThe last productions to align are `comment` and `string_comment`. In the JModelica production `comment`, the first nonterminal `string_comment` is optional. In Modelica, this nonterminal is mandatory but the production `string_comment` is completely optional. To align the varying occurrences of the optional, we inline the production `string_comment` and extract it with the surrounding optional. To converge the production `string_comment`, we deyaccify it.\n\nWith these transformations, we have handled all fail notes we can make disappear. Next, we consider the remaining productions. For some productions, we will be able to extract parts of the existing productions as new productions and thus, further align the grammars. The rest of the grammar gets transformed to the point where the differences become clearly identifiable.\n\nLogical Expressions\n\nThe productions modeling logical expressions in the Modelica specification allow for expressions in disjunctive normal form (DNF), with outer disjunctions and inner conjunctions. The single terms are logical factors, defined by an optional negation and a relation. JModelica does not restrict logical expressions to this normalized form but offers a conjunction, disjunction, or single term as a choice. The single term is a relation with or without a negation. We extract the single term choice to converge part of the grammar. The referenced nonterminal `relation` can be factored out and the newly formed choice of epsilon and the terminal `not` massaged into an optional. Factorizing the rest of the production `logical_expression` is not necessary but condenses the expression and emphasizes the difference between the two productions.\n\nArithmetic Expressions\n\nArithmetic expressions in the Modelica specification have an optional sign and a term expandable by an iteration of an additive operator and a term. The terms can have multiplications consisting of factors and multiplicative operators. Each factor is a power expression. In JModelica, the arithmetic expressions boil down to the same expression but with one difference. While the Modelica specification has one optional additive operator in the beginning, JModelica allows multiple signs in front of every power expression. A star expression with a choice between plus and minus models the sign. In the process of comparing the production, we can align two productions by extracting the arithmetic operators. The additive expression of JModelica approaches the structure of the Modelica production by inlining and deyaccifying it. If we inline the production `pow_exp` and rename the nonterminal `unary_exp` to `factor`, we set the ground to converge the multiplicative expressions. Renaming the nonterminal `multiplicative_exp` to `term` and deyaccifying the production lead to identical expressions. The newly named production `factor` can adjust to the structure of the Modelica production by deyaccification. For the transformation `deyaccify` to work, we have to combine a few transformations. As said before, we have to break the main choice into vertical productions. Additionally, the transformation only works if exactly two vertical productions, or two top-level choices, respectively, exist. Therefore, we need to factor out the nonterminal `factor` before applying the transformation `deyaccify`. Now, we can no longer align the arithmetic expressions of Modelica and JModelica.\n\nPrimary\n\nThe next production under investigation is `primary`. We start by comparing the terminals in the competing productions. JModelica has two additional choices, the terminals `UNSIGNED_INTEGER` and `TIME`. Looking at the flex definition for the terminal `UNSIGNED_INTEGER`, we can confirm\nthat the regular expressions for the terminals `UNSIGNED_INTEGER` and `UNSIGNED_NUMBER` agree. Thus, the terminal `UNSIGNED_INTEGER` does not carry any additional information and can be eliminated. The documentation for the time expression, which the parser creates with a reference to the terminal `TIME`, reveals that a time expression is a real number. A real number corresponds to the terminal `UNSIGNED_NUMBER` within the grammar. Therefore, we can eliminate the choice `TIME` as well. To eliminate the two choices, we string together the following transformations:\n\n```plaintext\nvertical( in primary );\nremoveV(\n primary:\n \"UNSIGNED_INTEGER\"\n);\nremoveV(\n primary:\n \"TIME\"\n);\nhorizontal( in primary );\n```\n\nAfter we have resolved the choices consisting of terminals, we move on to the choices that include nonterminals. The production `primary` serves as a good starting point to identify nonterminals and their productions that represent the same expressions. We see that the nonterminal `matrix` should produce expressions similar to the ones generated by the sequence with the nonterminal `expression_list`. We can see that the production `output_expression_list` will not find an identical counter production, as JModelica references the nonterminal `expression`. We can move this difference from the production `primary` to the production `output_expression_list` if we extract the single nonterminal `expression` in the corresponding choice. The productions for the nonterminal `functions_arguments` already share the same name but as they do not converge, we will take a look at them later in this section. The remaining choices have to somehow represent the same expressions and we will have to take a closer look at them together.\n\nFirst, we will transform the production `matrix`, then go on to the productions concerning `function_arguments` and close with the remaining choices.\n\n**Matrix and Expression Lists**\n\nThe production `matrix` references the nonterminal `matrix_row`, which shows promise for transforming it to agree with the production `expression_list`. We need the frequently used combination of the transformations `vertical` and `deyaccify` to align the production bodies and conclude with renaming the nonterminal `matrix_row` to `expression_list`. The same transformations are necessary to transform the production `matrix` into the form that the Modelica specification uses in the choice with the nonterminal `expression_list` in the production `primary`. If we inline the production `matrix` in the end, we have converged this part of the grammar. The exact chain of transformations, without the transformation `inline(matrix)`; in the end, is the following:\n\n```plaintext\nmatrix_row : expression | matrix_row \" ,\" expression\n// vertical( in matrix_row ); deyaccify(matrix_row); rename(matrix_row,\n expression_list);\n=> expression_list : expression ( \" ,\" expression)*\n matrix : expression_list | matrix \" ;\" expression_list\n// vertical( in matrix ); deyaccify(matrix);\n=> matrix : expression_list ( \" ;\" expression_list )*\n```\n\n**Function Arguments**\n\nThe JModelica production for `function_arguments` references a nonterminal `arg_list_p`. We can transform the nonterminal into a sequence of one occurrence and a star expression of\nthe nonterminal `function_argument` and inline the production. But no semantics-preserving transformation will converge the two colliding productions as the choice involving the terminal \"for\" starts with a general expression and not a list of the nonterminal `function_argument`. The nonterminal `for_indices` has a production that is not within the expressions section of the Modelica specification. As decided in the preliminaries, we do not follow up on the production. The production `function_argument`, which both versions reference, can be further aligned by inlining the production `partial_function_call`. As we have not yet looked at the production `parse_access`, we have to postpone any statement concerning the equivalence with the nonterminal `name`. But we already see the difference that JModelica references the nonterminal `function_arguments` whereas the Modelica specification allows the nonterminal `named_arguments`, a subset of the function arguments.\n\nNext, we continue with the remaining choices from the production `primary` and thus, the remaining productions within the two grammars. First, we examine the names and references of the Modelica specification versus the access expressions of JModelica. Second, we compare the expressions concerning function calls, including the so-called der expression.\n\n### Names, Component References, and Access Expressions\n\nWe have assumed in the introduction of JModelica, when surveying its parse tree, that the access productions model component references. After a closer look to the definitions, we reason that we can transform the access expressions to echo names and component references. To this end, we have to deyaccify and massage the production `parse_access` and inline the productions `parse_access_single`, `class_access_single`, `parse_access_loc`, and `first_class_access`. A few other transformations help to clarify the differences between the two productions, which involve a transformation we have not used so far, `distribute`. This transformation distributes a term over an inner choice. Distributing the production `parse_access`, factoring out the sequence \".\" \"IDENT\", and massaging the result three times will compress the production the most and still highlight the difference between the access expressions and the reference expressions. The next step is to rename the nonterminal `parse_access` to `name` and the nonterminal `access_expression` to `component_reference`. As the production `component_reference` is solely given by the nonterminal `name`, we could unfold the definition of `name` into the definition of the nonterminal `component_reference`. We could even think of equating both productions afterwards as they have the same definition. A transformation `equate` replaces one nonterminal with the other one and eliminates the production of the first one. But as we are comparing JModelica with the Modelica specification and the specification varies the definitions for the two productions, we keep both productions and only unfold the definition of the nonterminal `name` into the definition of the nonterminal `component_reference`.\n\n### Function Calls\n\nThe remaining productions in JModelica are `der_expression` and `function_call`. The respective nonterminals are choices in the production `primary`. Relating to the Modelica specification, these productions have to generate the same constructs as the Modelica specification choice ( `name` | \"der\" | \"initial\" ) `function_call_args` in the Modelica specification definition of primaries. After a quick investigation of the JModelica productions, we can establish that we will not be able to converge these choices. We can inline the production `der_expression`. Moreover, we can inline the production `function_call` and then extract it again without the first nonterminal as the production `function_call_args`. The new production actually converges with the specification production. But the definition of the nonterminal `primary` diverges as the keyword `initial` is missing and another nonterminal is referenced after the keyword `der`. \n4.3. MODELICA SPECIFICATION VS. JMODELICA\n\nTable 4.1: Final Converging and Failing Productions between the Modelica specification and JModelica\n\n<table>\n<thead>\n<tr>\n<th>Converging Productions</th>\n<th>Failing Productions</th>\n<th>Exclusive Modelica Productions</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>array_subscripts</td>\n<td>logical_expression</td>\n<td>logical_term</td>\n</tr>\n<tr>\n<td>subscript</td>\n<td>arithmetic_expression</td>\n<td></td>\n</tr>\n<tr>\n<td>annotation</td>\n<td>factor</td>\n<td></td>\n</tr>\n<tr>\n<td>expression</td>\n<td>primary</td>\n<td></td>\n</tr>\n<tr>\n<td>simple_expression</td>\n<td>output_expression_list</td>\n<td></td>\n</tr>\n<tr>\n<td>relation</td>\n<td>function_arguments</td>\n<td></td>\n</tr>\n<tr>\n<td>rel_op</td>\n<td>function_argument</td>\n<td></td>\n</tr>\n<tr>\n<td>term</td>\n<td>component_reference</td>\n<td></td>\n</tr>\n<tr>\n<td>named_arguments</td>\n<td>name</td>\n<td></td>\n</tr>\n<tr>\n<td>named_argument</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>comment</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>string_comment</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>logical_factor</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>add_op</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>mul_op</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>expression_list</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>function_call_args</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nWith this last transformation, we have exhausted the semantics-preserving transformations. The following subsection summarizes the result of the language convergence process of the Modelica specification and JModelica.\n\n4.3.3 Results\n\nThe transformations discussed in the preceding section are listed within the LCF as transformations to be applied to the JModelica source; see Listing C.5 in Appendix C.3. If we run the LCI with this LCF as input, we still get the statement that the target could not be reached as the grammars still differ. But we have expected that to happen as we could not completely converge the grammars. Listing A.3 in Appendix A.2 presents the transformed version of the JModelica grammar. If we call the comparator script directly, we get an output shown in Listing D.2 in Appendix D.1. The output details that the transformed JModelica grammar does not use any nonterminals exclusively anymore. The one nonterminal left exclusively within the Modelica specification grammar is logical_term. Various shared nonterminals converge while others still fail. Table 4.1 lists the converging and failing productions in a concise way.\n\nThe following paragraphs discuss each item of the failing productions list including the production exclusive to the Modelica specification.\n\nLogical Expressions\n\nThe difference between JModelica and the Modelica specification lies in the form of accepted logical formulas. The colliding productions read:\n\n\\[ \\text{Modelica} \\] logical_expression: logical_term ( or logical_term )\n\\[ \\text{Modelica} \\] logical_term: logical_factor ( and logical_factor )\n\\[ \\text{JModelica} \\] logical_expression: logical_factor ( ( and | or ) logical_factor )\nModelica only allows logical expressions in DNF for whose modeling, it needs the additional production `logical_term`. JModelica accepts any sequence of conjunctions and disjunctions.\n\n**Arithmetic Expressions and Factors**\n\nThe next minor difference is in the representation of arithmetic expressions. The difference regards the position and number of signs a term can have. In JModelica, each factor can have an arbitrary number of leading symbols, plus and minus. The Modelica specification allows one leading symbol, an additive operator, at the beginning of the arithmetic expression.\n\n**Primary**\n\nWith the production `primary`, the differences become larger. The terminals in the colliding productions agree. The difference lays in the Modelica specification choice\n\n```\n(name | \"der\" | \"initial\") function_call_args\n```\n\nagainst the two JModelica choices\n\n```\n\"der\" \"( expression \")\" | name function_call_args.\n```\n\nThe terminal \"initial\" is not part of the JModelica expressions notation. The terminal \"der\" is followed by a nonterminal `function_call_args` in Modelica and by an expression in parentheses in JModelica. The parentheses are also part of the function call arguments but the function call arguments then refer to an optional nonterminal `function_arguments`. As the definition of `function_arguments` can ultimately lead to a single expression as well, the difference lays in the other possibilities the production `function_arguments` allows.\n\n**Output Expression Lists**\n\nThe choice \"(\" output_expression_list \")\" in the Modelica specification with the definition of the referenced nonterminal is not identical to the one expression JModelica allows. The specification grammar can produce a list of expressions whereas JModelica allows only one expression.\n\n**Function Arguments and Function Argument**\n\nOne choice in the aforementioned production `primary` is \"{\" function_arguments \"}\", which is the same in both notations. But the definitions of the referenced nonterminal differ. The generation of an expression involving the keyword `for` in the Modelica specification works in the following way:\n\n```\nfunction_argument function_argument\" \"for\" for_indices\n```\n\nJModelica generates such an expression by:\n\n```\nexpression \"for\" for_indices\n```\n\nJModelica allows only an expression in front of the sequence \"for\" `for_indices`. The Modelica specification references the nonterminal `function_argument`, which allows more than an expression. The specification production also facilitates a list of the nonterminal `function_argument` separated a comma before going on to the for expression.\n\nThe productions `function_argument` collide through the arguments between the parentheses. JModelica jumps back to the nonterminal `function_arguments`, while the Modelica specification only allows the nonterminal `named_arguments`, making JModelica more permissive.\nComponent References and Names\n\nThe last productions we contrast towards each other are the component references and names. In JModelica, a dot at the beginning of a component reference leads to an identifier followed by a dot again without an array subscript in between. The rest of the definition agrees with the Modelica specification. The specification production allows the extra array subscript after the first dot and identifier.\n\nIn JModelica, the definitions of component references and names are identical. The Modelica specification defines them differently. The component references have an optional array subscript after each identifier while the names do not. Comparing the definitions of the names, we conclude that JModelica allows subscripts at all.\n\n4.3.4 Summary\n\nLarge parts of the two notations can be aligned with simple refactoring measures. Minor differences exist when it comes to logical and arithmetic expressions where JModelica is more permissive than the Modelica specification. With the definition of the nonterminal primary and the nonterminals referenced in there, more differences arise. The differences lay in the productions name, component_reference, function_arguments, function_argument, output_expression_list, and primary. The divergence of the production primary can be narrowed down to the choice (name | \"der\" | \"initial\") function_call_args in the Modelica specification colliding with the JModelica choices \"der\" \"(\" expression \")\" | name function_call_args.\n\nThe definitions of the nonterminal function_argument and name are more permissive in JModelica. Regarding the other differences, Modelica is more permissive. Apart from the terminal \"initial\", the differences are cases of one grammar being more relaxed than the other, making the grammars in some parts subsets and in other parts supersets of the other but not down right contradicting.\n\nWith the comparison of the Modelica specification and JModelica finished, we move on to the comparison of the Modelica specification with OpenModelica.\n\n4.4 Modelica Specification vs. OpenModelica\n\nWith the comparison of the Modelica specification and OpenModelica, the process starts all over again. We need an initial LCF to get first results of the comparison of the two grammar versions. Based on the results, we engineer the grammar transformations and update the LCF file. If we can no longer apply semantics-preserving transformations and decrease the differences between the two grammars, we analyze the end result with its remaining differences. OpenModelica, as mentioned during the description of the parse tree in Subsection 2.1.3 references more expressions from its nonterminal expression. This difference persists throughout the comparison. The other differences concern component references, names, named arguments, and the named arguments allowed after an expression involving the keyword for, with OpenModelica being more permissive. The Modelica specification extends the expressiveness of OpenModelica concerning for-or-expression lists, the input arguments for the built-in function initial(), and the list of arguments allowed before an expression involving the keyword for.\n\nThe topics of the upcoming subsections reflect the steps in the working process with the initial LCI in Subsection 4.4.1 the transformations in Subsection 4.4.2 and the end results in Subsection 4.4.3. By that, we maintain the structure of the description of the previous language convergence attempt.\n4.4.1 Initial LCI\nFor the new comparison, we can reuse the initial LCF for the language convergence of Modelica and JModelica and update it. We need to specify OpenModelica as a source with its extractor and as an input branch in the target; see Listing C.6 in Appendix C.4.\n\nRunning the LCI with this new LCF as input, we learn that the grammars do not converge. The sources share twenty nonterminals whose definitions collide. If we call the comparator script directly, we get the output shown in Listing D.3 in Appendix D.2. One production already converges, comment. Similar to JModelica, OpenModelica uses another style to name its terminals, and we can align these easily by renaming them. A fail note we will not address in terms of transformations is the first one about the production expression though we will inline the if expression and part of the simple expression. No transformation can decrease the core difference between the definitions as it includes nonterminals, which reference constructs not part of the specification’s expressions. We will take a closer look at this difference in the subsection that discusses the results of the language convergence process, Subsection 4.4.3. The remaining fail notes are addressed individually in the following subsection.\n\n4.4.2 Transformations\nThe transformations we apply to OpenModelica do not include any transformations we have not used in the previous language convergence process. We will mainly use transformations like massage, extract, vertical, or distribute to align the grammars. A complete list of the transformations applied to OpenModelica is given in Appendix E.2. We start the process with renaming terminals and go on to the remaining differing definitions of the shared nonterminals.\n\nRenaming Terminals\nRenaming the terminals leads to the following eight definitions of the overall 20 nonterminals already shared to agree: logical_expression, logical_term, logical_factor, factor, named_arguments, subscript, string_comment, and annotation.\n\nIf Expressions\nTo align the expressions that represent an if expression, we need to deyaccify the production elseif_expression_list. In advance, we massage the optional recursive call into a choice of epsilon and the nonterminal itself, after which we distribute and verticalize the production. After the deyaccification, the transformation inline replaces the occurrences of the nonterminals elseif_expression_list, elseif_expression, and if_expression with their definitions and deletes the corresponding productions. Now, the choices concerning if expressions agree.\n\nSimple Expressions\nThe OpenModelica production simple_expr agrees with the production simple_expression of the Modelica specification. But the production simple_expression also exists in OpenModelica. As the production expression, which references the nonterminal simple_expression, will not converge, we will shove the additional terms of the production simple_expression into the production expression, concentrating the differences there and aligning the production simple_expression by inlining the production simple_expr. Before inlining the production simple_expr, we need to eliminate the recursion in the definition. The transformations necessary are massage, factor, vertical, deyaccify, inline, and rename. We massage the optional in the first choice into an inner choice of epsilon and the previously optional part.\n4.4. MODELICA SPECIFICATION VS. OPENMODELICA\n\nsimple_expr ( \":=\" simple_expression )? | \"IDENT\" \"as\" simple_expression\n=> simple_expr ( ε | \":=\" simple_expression ) | \"IDENT\" \"as\" simple_expression\n\nThen, we distribute the production and factor out the nonterminal simple_expression.\n\n=> simple_expr | simple_expr \":=\" simple_expression | \"IDENT\" \"as\"\n simple_expression\n=> simple_expr | ( simple_expr \":=\" | \"IDENT\" \"as\" ) simple_expression\n\nNow, we have two top-level choices and we can deyaccify the production after applying the transformation vertical. With these transformations, we eliminated any recursion in the production.\n\n=> ( simple_expr \":=\" | \"IDENT\" \"as\" )* simple_expr\n\nHence, we inline the production simple_expression and rename the nonterminal simple_expr into the nonterminal used by Modelica, simple_expression. With this last transformation, we have aligned the productions simple_expression.\n\nOperators\n\nOpenModelica, similar to JModelica, does not have own productions for its relational, additive, and multiplicative operators. If we extract these operators, the productions relation, term, and arithmetic_expression as well as the extracted operator productions agree. Before extracting the additive operators, we first transform the production unary_arithmetic_expression. We factor out the nonterminal term and use the generated epsilon in the inner choice to massage the inner choice into an optional. Next, we inline the production unary_arithmetic_expression and then extract the additive operators. The relational and multiplicative operators can be extracted without prior transformation.\n\nPrimary\n\nIn the OpenModelica definition of the nonterminal primary, a terminal UNSIGNED_INTEGER exists as in JModelica. Consulting the OpenModelica lexer, we can confirm that the difference lays in the handling by the parser. The regular expressions are identical enabling us to eliminate the choice with the terminal UNSIGNED_INTEGER.\n\nThe other choices do not converge, though we will be able to align large parts of the primary definition except the expression involving the keyword initial and the choice including curly braces. We will revisit the choices through the referenced nonterminals in the upcoming paragraphs when we continue our way through the comparator output and its fail notes.\n\nComponent References\n\nReading through the definition of references in OpenModelica, we see that the production component_reference2 has a terminal \"OPERATOR\", which does not occur in the expressions section of the Modelica specification. Therefore, we will not be able to fully align the references. But we can align the rest of the definition. First, we need to massage the optional expression into a choice with an epsilon. To save us some transformations and writing, we extract the sequence (\"IDENT\" | \"operator\") array_subscripts?. The next step is to use the transformation distribute. As the transformation pushes every inner choice outside, the first choice \"IDENT\" | \"OPERATOR\" in the definition would also be distributed and we would have to reverse that. After the distribution, we can deyaccify the definition and massage the new definition to have the star expression at the end. If we inline both our helping productions and the production component_reference2, we have aligned the structure of the references. The last step is to look at the lexer definition of the terminals WILD and ALLWILD. The lexer maps the terminal WILD to\nan underscore and the terminal ALLWILD to two successive underscores. The definition of the terminal IDENT allows for the same constructs. We can construct the underscore, for example, by not taking the option of a dot and an array subscript and choosing the identifier instead of the operator while not expanding the expression through the iteration. Consequently, we can eliminate the two choices of terminals.\n\nOutput Expression Lists\n\nFor the output expression lists, we need the right parenthesis to move out of the definition. To reach this goal, we use several transformations. After we transform the definition by distribute, we factor out the right parenthesis of two choices and the sequence \",\" output_expression_list of the other two. We massage the generated inner choices with an epsilon expression into an optional expression. With the two top-level choices, we can deyaccify the expression, which leads to an expression without any recursion or inner choice and the right parenthesis at the end. If we inline the definition and extract it without the right parenthesis, the alignment is complete.\n\nMatrix Expression Lists\n\nThe matrix expression lists need a sequence of familiar transformations: massage to replace the optional, distribute, vertical, and deyaccify to remove the recursion, and massage again to move the star expression to the back of the production. If we inline the transformed production, we have aligned the choice in the production primary that referenced the matrix expression lists. The former matrix expression lists reference the nonterminal expression_list to whose definition we apply the same sequence of transformations as before to align the production.\n\nFunction Arguments and For-or-Expression Lists\n\nWe will first take a look at the definition of the nonterminal for_or_expression_list2. Transformations massage the optional sequence, distribute the definition, massage the choice of epsilon and the nonterminal expression into an optional, and deyaccify the definition, then inline it.\n\nNext, we consider the definition with the inlined production for_or_expression_list2. The production for_or_expression_list has an epsilon choice, which is massaged into an optional. We will not be able to align the definitions of the nonterminal function_arguments that uses the OpenModelica nonterminal for_or_expression_list. By using familiar transformations and new ones, like unfold, fold, and introduce, we carve out the differences in the productions function_arguments and for_or_expression_list. We introduce the nonterminal function_argument as an alias of the nonterminal expression and fold it into the production function_arguments. We also fold it into the definition of the nonterminal named_argument.\n\nThe transformation chain is the following:\n\n```plaintext\nintroduce(\n function_argument:\n expression\n);\nfold(function_argument in named_argument);\nfold(function_argument in for_or_expression_list);\nfold(function_argument in function_arguments);\n```\n\nThe whole process of transforming the function arguments is rather lengthy and does not add to the convergence of the grammars, only to the localization of the differences. Thus, we will skip a detailed description of the transformations and go on to the function calls.\n4.4. MODELICA SPECIFICATION VS. OPENMODELICA\n\nFunction Calls\n\nWe begin with the production `component_reference__function_call`. The production comprises three branches after transformations which convert the optional into an inner choice and distribute the definition. The branches relate to choices Modelica provides in its definition of the nonterminal `primary`. The OpenModelica nonterminal `function_call` corresponds to the nonterminal `function_call_args` in Modelica. Thus, we rename the nonterminal to its Modelica counterpart. As with JModelica, OpenModelica does not make a difference between names and references. For the sake of further alignment, we introduce the nonterminal `name` with the same definition of component references and replace the call for component references with a call for names. The exact sequence of transformations necessary can be found in Listing E.32 in Appendix E.2. We inline the production `component_reference__function_call` and factor out the nonterminal `function_call_args` to align the structures of the productions `primary`. The difference in the function call arguments lays in the mandatory nonterminal `function_arguments`, which is optional in Modelica. As the whole OpenModelica production `function_arguments` is optional, we can inline the production and extract it without the overall optional. These transformations converge the definitions of the nonterminal `function_call_args`.\n\nArray Subscripts\n\nThe last fail note refers to the definition of the nonterminal `array_subscript`. We need the transformation sequence we have used for the production `matrix_expression_list`. The sequence generates the expression that the Modelica specification defines in its production `array_subscript` between the squared brackets. If we inline the production `subscript_list`, the definitions agree.\n\nAfter we have processed the comparator output, we stop programming transformations. Next, we look at the LCI with the transformations and its output in the next subsection.\n\n4.4.3 Results\n\nWith the transformations from the previous subsection, we write the final LCF, see Listing C.7 in Appendix C.4, and run the LCI with it to get the remaining differences. The comparator script outputs the details specified in Listing D.4 in Appendix D.2. Similar to the LCI with JModelica, the Modelica specification and OpenModelica do not converge. The transformed OpenModelica grammar is shown in Listing A.6 in Appendix A.3. Table 4.2 summarizes the result. We will go through the failing and exclusive productions in the following paragraphs.\n\nExpressions, Function Expressions, and Names\n\nThe OpenModelica definition of the nonterminal `expression` encompasses all choices the Modelica specification definition includes. Additionally, OpenModelica references the nonterminals `code_expression` and `match_expression` as individual choices. They stay undefined in our limited view of the grammar. Another difference lays in the star expression of an inner choice that comes before the mandatory call to the nonterminal `simple_expression` if choosing the simple expression branch. The simple expressions are referenced in JModelica by the following expression.\n\n\\[\n( \\text{simple_expression} \\ \"::\" | \\text{\"IDENT\" \"as\" } )^* \\text{simple_expression}\n\\]\n\nBy means of this star expression, we produce a sequence of simple expressions. The simple expressions are separated by double colons. Alternatively, an identifier, or a list of such, is assigned to\nThe subsequent simple expression. This kind of listing and identification is not part of the Modelica specification. The definition of the referenced nonterminal part_eval_function_expression is also part of the Modelica grammar, namely the production function_argument. In Modelica, we have either curly braces around such a function expression or a name before it and parentheses around it. The function expression itself differs in that the names in OpenModelica allow more than the name in the Modelica specification. The production name with only dots and identifiers alternating is much more restrictive than the OpenModelica names which allows subscripts and the keyword operator. Furthermore, the Modelica specification references an optional nonterminal named_arguments where OpenModelica calls for the optional nonterminal function_arguments. OpenModelica contains the same choice as the Modelica specification with the specification's reference to named arguments but increases the possibilities due to the reference to the nonterminal function_arguments. The Modelica specification permits a list of named arguments resulting in a list of the sequence \"IDENT\" \"=\" function_argument. Besides the list of named arguments, OpenModelica allows a list of the nonterminal function_argument. At the same time, it is possible to have an expression involving the keyword for or to append named arguments after the list of function arguments. In summary regarding the production expression, OpenModelica is more permissive.\n\nPrimary, For-or-Expression List, and Names\n\nLooking at the definitions of the nonterminal primary, we observe that the versions vary in OpenModelica referencing the nonterminal for_or_expression_list instead of the nonterminal function_arguments, which the Modelica specification references. The Modelica specification production body of the function arguments,\nfunction_argument (\"\",\" function_arguments | \"for\" for_indices)? | named_arguments collides with the JModelica definition of for-or-expression lists,\n\n\\[\n\\text{function_argument (\"\",\" (function_argument \",\")* function_argument? | \"for\" for_indices)? }\n\\]\n\nThe OpenModelica production for_or_expression_list lacks the reference to the nonterminal named_arguments. The specification generates a possibly empty list of the nonterminal function_argument, separated by commas, and can be extended by either a for expression, in which case we need at least one element in the list, or the nonterminal named_arguments. OpenModelica also produces a list of the nonterminal function_argument though the list is generated slightly different. The list can be empty as well but no named arguments can be appended. Additionally, OpenModelica only allows one function argument before the for expression and not a list that goes beyond one element. The slight difference in the list generation becomes evident in the optional last function argument. The option means the list can end with a comma.\n\nThe other difference lays in what the Modelica specification models as a sequence with an inner choice, namely (name | \"initial\" | \"der\") function_call_args. OpenModelica generates empty parentheses after the terminal \"initial\". The choice with the terminal \"der\" is identical.\n\nThe productions name vary in the specification not allowing subscripts, as discussed before.\n\nNamed Argument, Component References, and the Keyword operator—\n\nThe differences in the two productions named_argument and component_references equal. Instead of an identifier, the inner choice \"IDENT\" | \"operator\" exists with the keyword operator as an additional choice.\n\nFunction Arguments\n\nOpenModelica also has a production function_arguments though the choice in the definition of the nonterminal primary references the nonterminal for_or_expression_list. The definitions for this production do not converge, either. The core of the OpenModelica definition is the same as the definition of the nonterminal for_or_expression_list without the outer optional. Additionally, the nonterminal named_arguments is a choice and an optional nonterminal at the end of the core of the for_or_expression_list production:\n\n\\[\n\\text{function_argument (\"\",\" (function_argument \",\")* function_argument? | \"for\" for_indices)? named_arguments? | named_arguments }\n\\]\n\nApart from the difference in the generation of the list of the nonterminal function_argument, the difference boils down to a nonterminal named_arguments allowed after the for expression and the single expression in front of the terminal \"for\". The list ending on a comma now makes sense as we can have named arguments with a comma as a separator as the last element in the list. But we can also have a named argument after the list without a comma. A difference we carry from the for-or-expression lists is the one element OpenModelica allows before the for expression whereas the Modelica specification models a list with at least one element. In addition, OpenModelica permits named arguments after a for expression which the specification does not generate.\n\nThe productions function_argument diverge, which is explainable due to the varying position of the function expression within the grammar. The Modelica specification offers the choices of a function expression or the nonterminal expression, which leads back to the beginning of the grammar excerpt. As OpenModelica already references the function expression at the top nonterminal expression, having the function expression in the definition of the nonterminal function_argument as an alternative is superfluous.\n4.4.4 Summary\n\nThe two grammar versions have a similar structure in parts of the grammar. Simple renamings have helped aligning a handful of productions. The differences that remain lay in the expressions, the names and component references, named arguments, and for-or-expression lists as well as the definition of the nonterminal primary. We omit the function arguments for a moment. All but the last two have OpenModelica being more permissive. Only with the definition of the nonterminal primary and the production for_or_expression_list referenced in there, the Modelica specification becomes more permissive. The first difference regards the empty parentheses after the keyword initial, the second the missing reference to the nonterminal named_arguments in the production body of the nonterminal for_or_expression_list. A special case is the production function_arguments, which is more permissive in OpenModelica concerning the named arguments allowed after a for expression but more restrictive concerning the number of arguments allowed before a for expression.\n\nAfter the completion of the comparison of the Modelica specification and OpenModelica, we proceed to the last comparison of JModelica with OpenModelica.\n\n4.5 OpenModelica vs. JModelica\n\nThe LCI of JModelica and OpenModelica marks the comparison of the grammar versions of open-source implementations of Modelica. The creators of each version have made independent decisions on design strategies and the implementation of certain features of Modelica. With the previous results of the comparisons of the two implementation versions against the Modelica specification, we can assume that we will not be able to converge JModelica with OpenModelica. We will more likely get a union of the previously reported differences between each version compared to the specification, with one or two exceptions. Fifteen of the 27 productions in the Modelica specification converge in both LCIs. If we compare the previous results, we have a number of production failures that are exclusive to one version of the grammar and some failures present in both LCIs. Exclusive failures mean that the other grammar version converges to the Modelica specification in the respective productions. These differences will still be present comparing OpenModelica and JModelica. The exclusive JModelica differences are the different forms of logical expressions, the number of signs within an arithmetic expression, and the output expression list that is a singleton. The language convergence process of OpenModelica revealed differences in the productions expression and named_argument where JModelica and the Modelica specification converged. As mentioned before, these differences concern the additional choices of match and code expressions, the listing of simple expressions, and a differently placed function expression as well as the keyword operator. They will still be the present in the new LCI. The productions primary, component_reference, function_arguments, and function_argument fail in both LCIs. These productions are the only ones with a chance at convergence. At the end of this last LCI, we will see that none of these productions converges.\n\nAs we have restricted the transformations to semantics-preserving ones, the final grammar versions at the end of the previous LCIs have the same expressiveness semantics-wise as the original ones. We will use the transformed versions of OpenModelica and JModelica as the starting points for the new LCI. These versions already have a similar structure due to the transformations towards the Modelica specification and share a large set of common nonterminals. Plus, the definitions are already familiar through the previous sections and more concise than the original ones. As the OpenModelica grammar has resembled the specification grammar in its structure from the start, some transformations would repeat itself to align JModelica’s grammar to the OpenModelica grammar. Thus, the use of the transformed versions will lead to\nfewer transformations and a faster result. On a side note, performing the LCI with the original grammar versions has lead to the same results, as expected.\n\nAgain, the following subsections go through the initial LCI in Subsection 4.5.1, the transformations (Subsection 4.5.2), and the final LCI in Subsection 4.5.3 ending with a summary of this section’s results (Subsection 4.5.4).\n\n4.5.1 Initial LCI\n\nThe initial LCI in this section requires a LCF file with OpenModelica and JModelica as the sources and input branches to the target. As we start with the transformed grammars, we already have the grammars in BGF. Therefore, we use the extractor from the small example in Section 3.55 that uses a script, which simply copies the text of one file into another file. The corresponding LCF file can be found in Appendix C.5. The output tells us that the target fails. The comparator output, as seen in Listing D.5 in Appendix D.3, details the result by specifying that fifteen nonterminals immediately agree. This result does not surprise given the preceding observations about the different comparison results. The differences lay in the expression, arithmetic and logical expression, the primary definition, function and named arguments, names, and component references. We will further align the grammars in the next subsection.\n\n4.5.2 Transformations\n\nIf we look at the differences, we observe that we cannot align most of them. The only production that converges after transformation is part_eval_function_expression. We can extract the function expression from one choice of the production function_argument and fold the nonterminal function_call_args into it. Moreover, we can eliminate the nonterminal name which we have kept for reasons intrinsic to the Modelica specification. As it shares the definition with the nonterminal component_reference, we can equate the two definitions and thereby, eliminate the nonterminal name. Because we have introduced the names in both grammars and to not introduce a new difference, we will actually write a transformation for both grammars to eliminate the names. Additionally, we can introduce the nonterminal for_or_expression_list to dissolve this nominal mismatch. If we define it by the nonterminal function_arguments, fold it into the production primary and unfold the definition of function_arguments into the production for_or_expression_list, we have further aligned the production primary and moved the difference to the production for_or_expression_list. Appendix E.3 lists the JModelica transformations within this LCI.\n\n4.5.3 Results\n\nWith only a handful of transformations, the JModelica version does not change much (for the LCF, see Listing C.9 in Appendix C.5). The transformed version of JModelica with for-or-expression lists and an own partial evaluation function expression, but without names is in Listing A.4 in Appendix A.2. Listing A.7 in Appendix A.3 shows the OpenModelica grammar without names. The output of the comparator script is shown in Listing D.6 in Appendix D.3. The summary can be found in Table 4.3.\n\nThe same productions that failed exclusively in one of the LCIs before are failing within this LCI, as well. For a detailed description of the differences causing these failures, refer to the comparison of the Modelica specification to JModelica and to OpenModelica in the previous sections. The productions that failed in both the previous LCIs still fail. Additionally, we have the failing production for_or_expression_list. We will take a closer look at the underlying differences causing these failures that were present in the two prior LCIs in the following paragraphs.\n### Converging Productions vs Failing Productions\n\n<table>\n<thead>\n<tr>\n<th>Converging Productions</th>\n<th>Failing Productions</th>\n<th>Exclusive OpenModelica Production</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>array_subscripts</td>\n<td>expression</td>\n<td>logical_term</td>\n</tr>\n<tr>\n<td>subscript</td>\n<td>logical_expression</td>\n<td></td>\n</tr>\n<tr>\n<td>annotation</td>\n<td>arithmetic_expression</td>\n<td></td>\n</tr>\n<tr>\n<td>simple_expression</td>\n<td>factor</td>\n<td></td>\n</tr>\n<tr>\n<td>relation</td>\n<td>primary</td>\n<td></td>\n</tr>\n<tr>\n<td>term</td>\n<td>output_expression_list</td>\n<td></td>\n</tr>\n<tr>\n<td>function_call_args</td>\n<td>function_arguments</td>\n<td></td>\n</tr>\n<tr>\n<td>named_arguments</td>\n<td>function_argument</td>\n<td></td>\n</tr>\n<tr>\n<td>expression_list</td>\n<td>named_argument</td>\n<td>component_reference</td>\n</tr>\n<tr>\n<td>comment</td>\n<td>for_or_expression_list</td>\n<td></td>\n</tr>\n<tr>\n<td>rel_op</td>\n<td>expression</td>\n<td></td>\n</tr>\n<tr>\n<td>add_op</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>mul_op</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>string_comment</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>logical_factor</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>part_eval_function_expression</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nTable 4.3: Final Converging and Failing Productions between OpenModelica and JModelica\n\n### Primary\n\nThe differences in the definition of the nonterminal `primary` are basically the same as from the comparison of JModelica and the Modelica specification. They lay in the nonterminal that JModelica references after the terminal \"der\" and the non-existing choice involving the keyword `initial`. Though, OpenModelica did not converge with the specification in this choice as OpenModelica only had empty parentheses and not a reference to `function_call_args`, we still have the difference that JModelica does not have the keyword `initial` at all. The difference concerning the der expression is the reference to the nonterminal `expression` instead of the nonterminal `function_call_args`.\n\n### Function Arguments\n\nSimilar to the previous comparisons, a slight difference in the generation of the list of the nonterminal `function_argument` exists. This difference leads to OpenModelica allowing a named argument after the list of function argument elements without a comma in between and a list ending on a comma. Another difference regards the part with the terminal \"for\". JModelica allows one nonterminal, namely `expression`. OpenModelica allows a function argument and a named arguments element at the end. The nonterminal `expression`, which is referenced instead of the nonterminal `function_argument`, does not lead to further differences. The function argument in OpenModelica is solely defined by `expression`. In this case, the difference ceases to exist. The difference about the named arguments after the for expression persists.\n\nThe difference in the definitions for the nonterminal `function_argument` relates to a difference encountered between OpenModelica and the Modelica specification. JModelica defines the function argument by a general expression or a function expression like the Modelica specification does. As OpenModelica places the function expression as a choice of its production `expression` and only references a general expression in its function argument, the grammar versions do not contradict but express the same at this certain point in the grammar. The actual difference lays in the definition of `expression`, which we already considered.\nComponent References\n\nThe difference between the definitions of component references is a union of the differences we encountered before. First, OpenModelica allows the keyword `operator` which JModelica does not include. Second, OpenModelica allows an array subscript after the first identifier if the reference starts with a dot.\n\nFor-or-Expression Lists\n\nThe definition of the nonterminals `for_or_expression_list` and `function_arguments` are the same in JModelica. In OpenModelica, the production `for_or_expression_list` misses the references to the named arguments and is fully optional compared to its function arguments. Consequently, apart from the additional named arguments in JModelica, we again have the difference that OpenModelica allows a function argument before the for expression which basically means the same as the expression that JModelica references and which we have discussed before.\n\n4.5.4 Summary\n\nThe two grammar versions differ the most in the three comparisons conducted as we cannot converge any common differences they have had with the Modelica specification. We find the slight differences in the logical and arithmetic expressions as well as the greater differences in the expressions. The only points where they agree more are concerning the function expressions and the single element in front of the for expression. In summary, OpenModelica is more permissive in the component references, the definition of primaries, named and function arguments, output expression lists, and expressions itself. The only production where JModelica is more permissive, apart from the small differences in the logical and arithmetic expressions, concern for-or-expression lists where JModelica allows named arguments at all.\n\nThe final results of our comparison of OpenModelica and JModelica mark the end of the LCI for Modelica expressions. We will end this chapter with a summary of the work presented and the results we have obtained before we go on to the evaluation.\n\n4.6 Summary of the Language Convergence for Modelica\n\nThe LCI delivered a comparison of three grammar versions of Modelica. The question at hand has been whether the three versions generate the same language. To this end, we have attempted to converge the grammar excerpts in pairs. The actions taken towards the answer of the question and the results of the investigation have been described in this chapter. For all three versions, we have written extractors to transform the grammar sources into BGF. We have carried out an initial LCI to learn the differences between the grammars. Then, we have programmed transformations to dissolve the differences and align the grammars. The transformations used are semantics-preserving to preserve the expressiveness of each grammar. At the end, we have conducted another LCI with the transformations specified to find the remaining differences.\n\nIn summary, the three versions all differ from each other. We are now interested in what the differences imply if working with Modelica and different simulation environments. With the results of the LCIs at hand, we continue with the evaluation of the work.\nChapter 5\n\nEvaluation\n\nThis chapter aims at evaluating the results of the three comparisons conducted in the previous chapter. In this chapter introduction, we will summarize the results to get an overview of the differences and assemble questions arising from these results. The questions guide the evaluation conducted in the following sections.\n\nThe summary is given in tables where each row concerns one construct in the grammar and the columns represent the two grammar versions in comparison. Gray-colored cells highlight the more relaxed version. An empty cell implies the feature described in the adjacent cell being not present in this grammar construct.\n\nTable 5.1 summarizes the results of the comparison of the Modelica specification and JModelica. As one can see, the grammar versions are more permissive in some cases and more restrictive in others. In four constructs, the Modelica specification is more permissive, namely, primaries, component references, function arguments, and output expression lists. In three cases, i.e., logical expressions, names, and single function arguments, JModelica is more relaxed. Concerning arithmetic expressions, both grammars contain features that extend the other grammar’s expressiveness.\n\nTable 5.2 presents the differences between the Modelica specification and OpenModelica. OpenModelica extends the expressiveness of the Modelica specification in terms of expressions, simple expressions, names, component references, and named arguments. The first two differences manifest themselves in the production expression. The last three differences concern the additional keyword operator and the fact that OpenModelica does not distinguish names from component references. The Modelica specification models the for-or-expression lists like function arguments, allowing more than OpenModelica. The specification also permits input arguments for the function initial(). Function arguments are split in their expressiveness. On the one hand, function arguments are more relaxed in OpenModelica with the possibility of named arguments after a for expression. On the other hand, function arguments are more permissive in the specification with a possible list of function arguments before said for expression.\n\nTable 5.3 displays the results of the LCI for OpenModelica and JModelica. OpenModelica has a higher expressiveness in seven cases. The arithmetic expression, as between the Modelica specification and JModelica, are more relaxed concerning the allowed operators as signs, but more restricted concerning the position and the number of the signs. The cases of JModelica having a higher expressiveness than OpenModelica include for-or-expression lists as JModelica, like the Modelica specification, does not restrict its function arguments to the slimmer version of for-or-expression lists as OpenModelica does. The other case is the order of connectors in logical expressions.\n### Modelica Specification | JModelica\n---|---\n**Logical expressions** | DNF | Arbitrary order\n**Arithmetic expressions** | Optional sign in the beginning of an arithmetic expression | Multiple signs in front of power expressions\n| Permitted operators as signs: | Permitted operators as signs: |`````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````\nIn all three comparison, we observe that no distinct relation exists between any of the grammars. From this result, new questions arise, including:\n\n- What does one grammar generate that the other grammar does not?\n- Can we generate something similar to what the other grammar can produce?\n- What might be the origins of the difference?\n- On a broader scale, is one grammar version a super-/subset of another?\n- What do we have to bear in mind switching from one simulation environment to the other?\n\nWe will focus on these questions in the first section of this chapter, Section 5.1. As a grammar engineer, other questions emerge:\n\n- What transformations have been used and what transformations have not been used?\n- Would different transformations lead to different results?\n- Does the order of application matter?\n- In conclusion: Is the outcome of the comparison correct?\n\nSection 5.2 delves into a discussion of these questions. At the end of this chapter, we consider the LCI as the means to answer our research question (Section 5.3).\n\n### 5.1 Analysis of the Results\n\nIn this section, we attempt to evaluate the results collected during the comparison of the Modelica grammar versions. We start with a brief inspection of the parse trees before moving on to the implications of the differences on the generated language (Subsection 5.1.1), the overall relation (Subsection 5.1.2), and the implications on the use of different simulation environments (Subsection 5.1.3).\n\nThe comparison of the different Modelica grammars has yielded transformed grammars for JModelica and OpenModelica. These transformed versions resemble the grammar structure of the Modelica specification. The parse trees of the transformed grammars echo the semblance; see Figures 5.1 and 5.2. Figure 5.3 replicates the original Modelica specification tree, shown in Figure 2.1 for the sake of convenience. We have conducted a quick comparison of the original parse trees in Section 2.1. If we now compare the original Modelica specification parse tree with the parse trees of the transformed grammars, we observe an alignment of the tree structures in comparison to the previous tree structures. The OpenModelica parse tree still differs from the other parse trees by the three additional nodes referenced by the node `expression`. Additionally, the lower part of the tree appears to be more complex. This impression is due to the exclusive node `for_or_expression_list` and one of the nodes referenced by the node `expression`, namely `part_eval_function_expression`. The tree visualizes that differences, apart from variations in the definitions, still exist, especially in the modeling of function arguments. The JModelica tree reflects the structure of the specification tree more closely than OpenModelica. The varying parts of the trees concerning function arguments highlight a major point for differences between the grammar versions. In a converging grammars scenario, the parse trees would have been identical after transformation. But contrasting the transformed parse trees against the original specification parse tree reflects the inherent differences between the various grammar productions.\n\nIn the next subsection, we will focus on the implications of the differences between the grammars. The first three questions in the list at the beginning of this chapter guide our evaluation of the results of the LCIs.\nFigure 5.1: Parse Tree of the Transformed JModelica Expressions\nFigure 5.2: Parse Tree of the Transformed OpenModelica Expressions\nFigure 5.3: Parse Tree of the Modelica Specification Expressions\n5.1. ANALYSIS OF THE RESULTS\n\n5.1.1 Implications of the Individual Differences\n\nIn this subsection, we will analyze what one grammar can generate that the other grammar does not include and how close we can come to remodel that rejected expression in the other grammar. Moreover, we will try to find a reason for the occurrence of the difference. Before starting with the analysis, a short note on grammars from specifications and from implementations. Implementation grammars, such as the ones extracted from the OpenModelica and JModelica parser descriptions, are usually more permissive than grammars from language specifications [11]. OpenModelica and JModelica work on the language Modelica. Hence, whenever their grammar versions are more permissive compared to the Modelica specification, the consequences are acceptable as the grammars still accept the specification’s version.\n\nModelica Specification vs. JModelica\n\nThe constructs considered within this paragraph are logical and arithmetic expressions, primaries, output expression lists, function arguments, component references, and names.\n\nLogical Expressions The first difference between the Modelica specification and JModelica appears in the productions for logical expressions. The specification only allows logical expressions in DNF. JModelica does not restrict the logical expressions to this normal form. JModelica allows an arbitrary order of conjunctions and disjunctions, which the Modelica language does not permit. The Modelica language specification document details that a disjunction has a higher precedence than a conjunction. The higher precedence leads to a logical expression automatically being in DNF if no parentheses are given. The grammar reflects this circumstance by using two productions to model the logical expressions. JModelica does not define any precedence between the two logical connectors. Without any parentheses, a logical expression is parsed from left to right regardless of the connectors. To determine another order of parsing, parentheses are necessary. The grammar reflects this behavior. As every logical expression of disjunctions and conjunctions can be transformed into DNF, the logical expressions have the same expressiveness. But concerning the expressiveness of the grammar, JModelica is more permissive. A reason behind JModelica choosing not to restrict the logical expressions might be in that normalizing logical expressions potentially leads to much larger expressions with a length up to the exponential of the original. Therefore, JModelica has possibly decided for convenience reasons to not restrict the expressions to DNF.\n\nArithmetic Expressions Arithmetic expressions vary in the characteristics of a sign. The Modelica specification allows an optional sign at the beginning of an arithmetic expression and only additive operators as the indicator for the type of the addition afterwards. Each term within the addition can have numerous multiplications of factors that can be a power expression or a simple primary. These factors are all implicitly positive. In the arithmetic expressions of JModelica, each factor of a multiplication can have an arbitrary number of algebraic signs ahead of a power expression or a simple primary. This production implicates that the overall arithmetic expression can have a leading sign. But the position of the sign is not restricted to the forefront. Considering the workings of mathematics, numerous signs can be collapsed into a single one with the common rules of two minuses becoming a plus and a minus and a plus becoming a minus. The result of a multiplication is either positive or negative. As a consequence, a multiplication of signed numbers can be expressed as a multiplication of unsigned numbers with a corresponding sign in front of the term that consists of the multiplication. A single sign in front of a term can be merged with the additive operator between the terms that leads to an arithmetic expression with terms separated by additive operators and an optional sign at the beginning, the absence of a sign likewise\nindicating that the term is positive. Thus, the expressiveness concerning arithmetic expressions is identical as we can transform one arithmetic expression modeled according to JModelica into an arithmetic expression modeled according to the Modelica specification. The difference, again, lies in the expressiveness of the grammar and not in the mathematical expressiveness of the arithmetic expressions, with JModelica being more permissive. Another difference is that JModelica only allows a plus or minus as a sign whereas the Modelica specification permits all its additive operators, which include bitwise addition and subtraction.\n\n**Primaries** In the examination of the arithmetic expressions, we have come across primaries, which we deal with next. The collisions in this production are between the following two excerpts of the respective Modelica specification (the first excerpt) and JModelica (the latter one) production.\n\n\\[\n(\"\\text{der}\" \\mid \"\\text{initial}\") \\text{ function_call_args} \\leftrightarrow \"\\text{der}\" \\text{ \"(\" expression \")\"}.\n\\]\n\nThe keyword initial references the built-in function initial() in Modelica. Within JModelica, the keyword initial does not appear in this context. The JModelica user’s guide reveals that the function initial() is only partially supported. JModelica allows different kinds of models to be created and translated through different compile functions. Not all models include this built-in function. Hence, the reason this particular keyword is not part of the grammar may lie in the inconsistency of handling the function initial(). The nonterminal following the keyword der exhibits the next and last difference. The referenced nonterminal function_call_args allows an optional nonterminal function_arguments between parentheses. JModelica demands an expression. Going through the grammar again, starting from the referenced nonterminal expression, makes it possible to put almost the same expression after the keyword der. But to actually reach the production function_arguments in the next round, the production primary either adds curly braces or a nonterminal name and opening and closing parentheses. The JModelica representation is, therefore, more restrictive.\n\n**Output Expression Lists** Output expression lists represent a similar problem. JModelica allows one expression, whereas the Modelica specification allows a possibly empty list of expressions separated by commas. In JModelica, similar lists are possible with a trick: Starting from the nonterminal expression, we choose the sequence name function_call_args, adding the nonterminal name, or the sequence {\" function_arguments \"}, in the production primary. The nonterminal function_arguments models a sequence function_argument (\",\" function_argument)∗ where we can replace each nonterminal function_argument with its first choice expression. By choosing the sequence name function_call_args, we can model an empty list. At this point, it is worth mentioning that the Modelica specification allows a list of commas in parentheses. It is debatable how much sense a list of commas makes and whether the compiler accepts it.\n\n**Function Arguments** The aforementioned function arguments differ in one point. The difference is the one expression that is allowed before the terminal for in contrast to a list of the nonterminal function_argument separated by commas. As before, we could go through the grammar again and emulate the same part in front of the terminal for with an additional name or curly braces around the part. Taking into consideration previous Modelica specifications, we discover that before the most recent version, no production function_argument exists. The production function_arguments referenced the nonterminal expression. This development partly explains why JModelica references an expression before the terminal \"for\" but it does not give hints as to why JModelica does not allow a list of expressions and why it has changed.\n5.1. ANALYSIS OF THE RESULTS\n\nthe expressions reference to a function argument reference for the rest of the production but the for expression. The definitions of the nonterminal function_argument collide in the allowed function arguments. JModelica references the nonterminal function_arguments instead of the nonterminal named_arguments. That makes JModelica more permissive.\n\nComponent References and Names The last difference in the result of the Modelica Specification vs. JModelica comparison refers to component references and names. As mentioned before, the specification restricts names to alternating dots and identifiers while JModelica models the names in the same way as component references. Component references allow array subscripts after identifiers. The Modelica specification uses the production name for specifying function names and paths. Function names and paths do not have array constructs in their name; to incorporate subscripts in the grammar production is inaccurate. Thus, the specification models the names and component references more precisely, only permitting subscripts where they are justified. The difference between the definitions of the component references boils down to only allowing subscripts after two times a dot and an identifier if the reference starts with a dot. The origins for this difference are unclear. The evolution of the language Modelica has lead to the recent introduction of a dot at the beginning of a component reference regarding the grammar. This initial dot is incorporated by JModelica but not to the same extent.\n\nWe discuss the differences encountered between the Modelica specification and OpenModelica in the next paragraph.\n\nModelica Specification vs. OpenModelica\n\nThe productions expression including its referenced nonterminals and their definitions if available, primary, for-or-expression-list, named_argument, and component_reference are the topics of this paragraph.\n\nExpressions We start with the differences in the definition of the nonterminal expression. All differences are instances of OpenModelica being more permissive. The two big differences, we cannot explain with our restriction of the grammar, are the references to the nonterminals code_expression and match_expression. The nonterminals model constructs that are part of the Modelica specification, as well. The reason behind placing them at this point in the grammar is not obvious, equally the question whether the definitions agree. This problem must be shifted to future work. As already discussed in the previous chapter, we can build a list of simple expressions separated by double colons or the sequence \"IDENT\" \"as\". The Modelica specification does not include a list of simple expressions with these types of separation. The definition of the referenced nonterminal part_eval_function_expression can be found as a part of the Modelica specification production function_argument. To reach the function expression in the specification, the grammar at least generates either curly braces or a name and parentheses.\n\nFunction Expressions and Names The differences between the function expressions themselves lay in the definition of the name in OpenModelica versus the name definition in the Modelica specification and using the nonterminal function_arguments instead of the nonterminal named_arguments. The production name with only dots and identifiers alternating is much more restrictive than the OpenModelica name, which is equal to component references and as such allows subscripts and the keyword operator. A reason behind the restrictiveness of the Modelica specification concerning names has been discussed in the previous paragraph. The differing arguments in the function expressions mean that OpenModelica allows more than the specification. The specification permits a list of named arguments resulting into a list of the sequence\n\"IDENT\" \"=\" function_argument separated by commas. Additionally, OpenModelica allows a list of the nonterminal function_argument. At the same time, it is possible to have an expression involving the keyword for or to append named arguments after the list of function arguments. The origin of the difference is unclear. The production function_arguments exists in OpenModelica, as well. The difference lies in the number of expressions allowed in front of the terminal \"for\" and to append a list of named arguments after such a for expression. The succeeding named arguments make OpenModelica more permissive. The list of function arguments preceding the for expression is discussed in the next paragraph.\n\nPrimaries and For-or-expression lists The next differences we examine are in the definition of primaries and the referenced construct for-or-expression lists. Primaries in the Modelica specification include the keyword initial followed by the nonterminal function_call_args. In OpenModelica, the keyword is followed by empty parentheses. Referring to the language documentation for Modelica yields that the built-in function initial() has no input arguments. This information validates OpenModelica's version with explicitly allowing only empty parentheses. The Modelica specification presents a grammar that permits arguments for the function initial(). As a side note, the primaries also include the keyword der followed by the non-terminal function_call_args. Both versions allow empty parentheses after the keyword der. The keyword plus the function call arguments model the function der(). From the language document, we learn that the function, which returns the derivative of the input, needs to have input parameters. Thus, the grammars do not strictly reflect the requirements for this function. In the last difference between the primaries, OpenModelica references the nonterminal for_or_expression_list whereas Modelica calls for the nonterminal function_arguments in the choice, which includes curly braces. As described during the comparison of OpenModelica and the Modelica specification, the for-or-expression list lacks a reference to named arguments and allows only one element before the terminal for. We could build a list in front of the “for ” part by wandering through the productions again and would end up with an additional name and parentheses or curly braces. The named arguments can be reached if we designate the last function argument in the list to model the named arguments and walk through the grammar again. Until we arrive at named arguments, a name and parentheses have been added. A minor difference in generating the list of function arguments exists, which allows the list in OpenModelica to end on a comma. It is arguable how reasonable this way of modeling the list with a possible ending comma is. The comma becomes valid when modeling the nonterminal function_arguments in OpenModelica. In its definition, a named argument can end the list, which warrants a comma as a separator. With this comma, OpenModelica follows the Modelica specification in separating elements of a list by commas. But the production also allows one to not place a comma between the last function argument and the ending named arguments, which does not follow the specification's approach of element separation in lists.\n\nKeyword operator The last difference investigated in this paragraph regards the keyword operator, which OpenModelica uses in its definition of the nonterminals named_argument and component_reference. The remainders of the definitions agree. Within the Modelica specification, the keyword operator only exists as a class prefix in the production class_prefixes. The exact motive behind embedding the keyword in these productions is not visible but may refer to operator overloading. We will take a closer look at the keyword and its possible meaning in the chapter about the implications of the differences on using different simulation environments.\n\nThe implications of the differences between OpenModelica and JModelica follow in the next paragraph.\n5.1. ANALYSIS OF THE RESULTS\n\nOpenModelica vs. JModelica\n\nThe differences between OpenModelica and JModelica form two classes. One class contains the productions where one grammar converges with Modelica while the other does not. The implications of these differences are the same as mentioned in the previous two paragraphs. For example, the difference in logical expressions between OpenModelica and JModelica is the same as the difference between JModelica and the Modelica specification. OpenModelica restricts logical expressions to DNF like the Modelica specification does. The difference continues to exist with the comparison of OpenModelica and JModelica. The differences that belong to the second class stem from both grammars failing to agree with the Modelica specification. As by the result of the LCI of OpenModelica and JModelica, these differences do not collapse but persist, the exception being function expressions. In this comparison, the differences are basically a union of the differences encountered before. The component references, for example, diverge between OpenModelica and the Modelica specification because of the additional keyword `operator`. The LCI of the Modelica specification and JModelica has revealed that JModelica does not allow a subscript after the first identifier if the reference starts with a dot. The differences merge when comparing OpenModelica and JModelica. OpenModelica includes the keyword `operator` and allows said subscript.\n\nAfter analyzing the individual differences, we investigate the general correspondence between the grammars. We focus on the question whether one grammar is a sub- or superset of another.\n\n5.1.2 Overall Relation and Equivalence\n\nWith the differences still remaining between the grammars after transformation, we can state that the grammar versions do not correspond. The grammars are not equivalent, which means, strictly speaking, they do not model the same language. The follow-up question is whether one grammar has a higher expressiveness. In any case, we cannot detect a distinct relation between the grammar pairings. In some cases, one grammar is more permissive, in other cases, it is the other way around, which means they are neither a subset nor a superset of one another. Albeit, we can make some observations concerning the relations and expressiveness of the versions.\n\nThe Modelica specification is more restrictive when it comes to names, which both OpenModelica and JModelica do not distinguish from component references. As discussed before, this restrictiveness might reflect a more correct way of expressing names. JModelica is more permissive concerning logical and arithmetic expressions in comparison to the Modelica specification and OpenModelica. Furthermore, the productions `function_argument` in relation to Modelica and `for_or_expression_list` regarding OpenModelica are more relaxed. In all other productions, JModelica is equally or less expressive than the other two versions. The Modelica specification models the component references, function arguments, output expression lists, and the primaries by the input arguments for the function `der()` and by the function `initial()` present in a more permissive way. Overall, JModelica is more restrictive than the Modelica specification apart from the logical and arithmetic expressions and a single function argument. The same holds for the relation of JModelica towards OpenModelica, except logical and arithmetic expressions and for-or-expression lists. OpenModelica has a higher expressiveness with respect to component references, function and named arguments, output expression lists, expressions, and primaries in comparison with JModelica. The only expression, apart from the logical and arithmetic expressions, that is more permissive in JModelica is the for-or-expression lists. Comparing OpenModelica with the Modelica specification yields a similar observation. In addition to the aforementioned definition of the nonterminal `name`, the OpenModelica productions `component_reference`, `named_arguments`, `function_arguments`, except the terms allowed before a for expression, and `expression` are more permissive. The Modelica specification only\nexceeds OpenModelica’s expressiveness when it comes to for-or-expression lists and the non-terminal between the parentheses after the keyword initial. Concerning the keyword initial, we have recorded that the possible input for the function initial() in the Modelica specification is erroneous according to the language specification document. In general, OpenModelica is more permissive with two exceptions and the special case of function arguments with being more restrictive and permissive at the same time.\n\nThe differences encountered are all cases of one grammar being more relaxed than the other. Exhibiting a difference, one grammar always includes the possibilities of the other grammar but extends them by further references. No definite contradictions exist. In case a code example adheres to a more restrictive production, the more relaxed version will also accept it. One has to be careful with code that complies with the more permissive production where a more restrictive grammar might reject the code.\n\nIgnoring minor differences, the three versions form a loose relation of OpenModelica being a superset of the Modelica specification being a superset of JModelica. With OpenModelica being an implementation of a grammar that is optimized for readability, the first result does not astonish. JModelica, though being more relaxed in some cases, does not express more than Modelica, which is unusual for a grammar derived from an implementation. OpenModelica strives to develop a full implementation of the Modelica language openly available. JModelica does not set its goal to accomplish a complete implementation. The differences in the grammars reflect the varying goals of OpenModelica and JModelica.\n\nThe next subsection discusses the implications of the differences on the use of different simulation environments.\n\n5.1.3 Implications of the Result on Using Different Simulation Environments\n\nSo far, we have discussed the individual differences and what they mean in terms of words generated by one grammar, but not by the other one. As these grammars describe a programming language, the next step is to evaluate what these discrepancies mean if different simulation environments are fed the same Modelica code. Various scenarios exist. First, the Modelica code adheres to the Modelica specification. If using a simulation environment that uses a more permissive grammar, no problems occur that can be attributed to a differing grammar. If the grammar of the simulation environment is more restrictive, one must be careful as the code might include passages that the more restrictive grammar does not generate. In a second scenario, the Modelica code follows the grammar rules of a simulation environment that has a grammar varying from the Modelica grammar. The programmer has to pay attention if switching to another simulation environment. The code may be rejected by the new environment if the new grammar varies from the other grammar in such a way that it is more restrictive. Writing code for a new simulation environment, the programmer needs to familiarize her- or himself with what is possible within the other grammar and not rely on what the former simulation environment accepts. For the simulation environments OpenModelica and JModelica, the previous subsection has revealed that they do not have a distinct relationship. With a distinct relation between the grammars, we would have been able to state that switching from the more restrictive one to the more permissive one does not lead to differences concerning expressions grammar-wise. The programmer would only need to revise his code if switching from the simulation environment with the more permissive grammar to the environment with the less permissive grammar. Unfortunately, OpenModelica and JModelica do not fully adhere to the Modelica specification and both are more restrictive in some passages and more permissive in other ones, compared to the specification and compared to the other one. Therefore, the programmer has to review his code whenever switching the simulation environments. In the remainder of this subsection, we will give hints on which\nexpressions might cause problems and where pitfalls lurk.\n\nExpressions and Function Expressions\n\nJModelica adheres to the Modelica specification. Difficulties might arise if presenting JModelica with code written in accordance with the OpenModelica grammar. OpenModelica references match and code expressions in the definition of the nonterminal expression. What the consequences of modeling the expressions this way are in its entirety, we cannot predict. For this excerpt of the grammar, the existence of code and match expressions within the definition of the nonterminal expression means that JModelica rejects code that uses a code or match expression whenever the situation warrants an expression. As mentioned above, a further investigation must be postponed. Another difference of OpenModelica compared to the Modelica specification and JModelica is the reference to a function expression at this stage in the grammar. The implication is that the grammar of OpenModelica models the following minimal expression, a function with the name “someFunction” and no input arguments:\n\nfunction someFunction()\n\nThe JModelica grammar and the Modelica specification do not accept this expression. A corresponding minimal function expression for the specification and JModelica require curly braces, or a name accompanied by parentheses, and an identifier.\n\n{ someId = function someFunction() }\nsomeOtherFunction( someId = function someFunction() )\n\nThe OpenModelica grammar accepts the second example, as well. The function expressions allow the function to have input arguments. The Modelica specification requires named arguments, which means that all arguments are of the form \"IDENT\" \"=\" function_argument, e.g., \\((x = 1, y = 2)\\). OpenModelica and JModelica allow function arguments, which results in arguments of the form function_argument possibly followed by named arguments, e.g., \\((1, 2, x = 1)\\). They also allow a for expression as input argument, which may look like the following expression:\n\nfunction sum( i for i in 1:10 )\n\nAs both simulation environments permit such an expression, the expression is not rejected according to the grammar if changing the environment. The differences in the definition of function arguments are discussed below.\n\nLogical Expressions\n\nWithin the logical expressions, two pitfalls exist, one being different evaluation orders, the other being expressions not accepted by the Modelica specification. JModelica reads the following logical expression from left to right with first evaluating the disjunction and then the conjunction coming to the result that the expression is false.\n\ntrue or x and false\n\nThe Modelica specification intends to first evaluate the conjunction followed by the evaluation of the disjunction which leads to the expression evaluating to true. The two boolean values are placeholders for any logical expression that evaluates to the boolean value given a specific assignment of the involved variables in the logical expression. The same expression with parentheses, as depicted below, is possible within JModelica but not within the Modelica specification, as the expression is not in DNF.\n\n(true or x) and false\nAs OpenModelica follows the Modelica specification in modeling logical expressions, one has to be careful when switching platforms. Feeding JModelica with Modelica code that adheres to the Modelica specification might result into an evaluation of a logical expression not as intended due to the absent precedence in JModelica. The same problem might exist when switching from JModelica to another simulation environment. The evaluation order might change again with precedence present. In addition to the varying evaluation orders, logical expressions allowed in JModelica can be rejected by OpenModelica or other platforms that model logical expressions only in DNF.\n\n**Arithmetic Expressions**\n\nThough the arithmetic expressions have the same expressiveness considering the mathematics behind them, the grammars vary. JModelica accepts the following arithmetic expression whereas the Modelica specification and the OpenModelica parser do not permit such an expression.\n\n\\[-2 + (-1)\\]\n\nThe sign in front of the second summand is not possible in the Modelica and OpenModelica grammars. A more complex expression is:\n\n\\[-((-(2))) + (5 \\times (-7) \\times ((+(+9)))\\]\n\nThis expression exhibits the ability to have more than one sign before a factor in JModelica. If a bitwise operator is used as a sign in OpenModelica, JModelica rejects the expression according to its grammar.\n\n**Primaries**\n\nThe differences in the definition of primaries concern the keywords `initial` and `der` and the list between curly braces. JModelica does not include the keyword `initial`. Without the keyword being a reserved word, it is possible to use it as an identifier. But, as mentioned above, the function that is referenced by this keyword is only partially supported by JModelica. One has to be careful with the function `initial()` if using JModelica. Researching the built-in function `initial()` in JModelica has revealed that several other built-in Modelica functions are not supported within JModelica [6].\n\nThe keyword `der` refers to the derivative function. In OpenModelica and the Modelica specification, function call arguments follow the respective terminal \"der\", which leads to parentheses and a list of function arguments. The grammar generates the expression `der(x,y)`. JModelica references an expression that generates the expression `der(x)`, for example, but not a list of function arguments. The grammar does not allow for a list of arguments in JModelica. According to the grammar, more complex expressions are possible but they are also permitted in OpenModelica and the Modelica specification.\n\nThe last difference mentioned in the introductory sentence regards the list generated between curly braces. This failure in convergence involves the productions `function_arguments` and `for_or_expression_list`. We will take a look at them together in the next but one paragraph.\n\nWe move on to a nonterminal that represents a choice within the production `primary` surrounded by parentheses, the output expression lists.\n\n**Output Expression Lists**\n\nIf a function returns more than one output expression, a list of output variables is needed to use all return values. Output expression lists model this list to whose elements the result expressions are assigned to. JModelica references only one expression, which allows for the\nexpression \\((x)\\). OpenModelica and the Modelica specification permit a list of output variables, e.g., \\((x, y, z)\\). The difference resembles the one we described in the previous paragraph about the input arguments allowed for the function \\(\\text{der}(\\ldots)\\). Therefore, code adhering to the Modelica specification and working in OpenModelica should be revised with respect to output expressions if using JModelica.\n\n**Function Arguments and For-or-expression Lists**\n\nWe have already taken a look at what function arguments can generate when inspecting function expressions at the beginning of this subsection. The definitions for function arguments all differ between the three grammars. We have already discussed the difference in the list generation of function argument elements. The remainder of the definitions of function arguments in OpenModelica and JModelica comes to an agreement. The difference in list generation leads to JModelica modeling the following expressions:\n\n\\[\n\\text{arg0}, \\ \\text{arg1}, \\ \\text{arg2} \\\\\n\\text{arg0}, \\ \\text{arg1}, \\ x = \\text{arg2}\n\\]\n\nOpenModelica models the subsequent expressions:\n\n\\[\n\\text{arg0}, \\ \\text{arg1}, \\ \\text{arg2} \\\\\n\\text{arg0}, \\ \\text{arg1}, \\ \\text{arg2}, \\\\\n\\text{arg0}, \\ \\text{arg1} \\ x = \\text{arg2} \\\\\n\\text{arg0}, \\ \\text{arg1}, \\ x = \\text{arg2}\n\\]\n\nThe way JModelica models the list generation is in accordance with the Modelica grammar. The second and third OpenModelica example are rejected by the Modelica specification and JModelica. It is arguable even within OpenModelica whether a list is allowed to end on a comma.\n\nThe next difference exists concerning the expressions involving the keyword `for`. JModelica and OpenModelica agree on the definition as the referenced function argument before the keyword `for` in OpenModelica is defined solely by an expression. JModelica demands an expression at this position in its definition. The Modelica specification approves a list of function arguments that exceeds the singleton expression of OpenModelica and JModelica. Thus, a code excerpt that the Modelica specification accepts is rejected by the other two grammars. An expression allowed within the Modelica specification but not within JModelica and OpenModelica is:\n\n\\[\n\\text{arg0}, \\ \\text{arg1}, \\ i \\ \\text{for} \\ i \\ \\text{in} \\ 1:10\n\\]\n\nThe first two arguments would not be generated by the JModelica and OpenModelica grammars. On the contrary, OpenModelica permits a list of named arguments after a for expression which both JModelica and the Modelica specification do not model. An example of such an expression is:\n\n\\[\ni \\ \\text{for} \\ i \\ \\text{in} \\ 1:10, \\ x = \\text{arg0}, \\ y = \\text{arg2}\n\\]\n\nAs the title of this paragraph suggests, for-or-expression lists and function arguments relate somehow. These two nonterminals are one cause for the failure of convergence of the definitions of primaries. For-or-expression lists model similar expressions to function arguments. The production name originates from the OpenModelica grammar. OpenModelica does not allow the full spectrum of function arguments between curly braces in the primary definition but only a portion of it. The core definition is the same but lacks the reference to named terminals. As a consequence, OpenModelica does not allow named arguments between curly braces. In addition, it allows empty braces. Expressions generated by OpenModelica include:\nAgain, the lists are generated with possibly a comma as the end symbol. Lists OpenModelica does not accept include:\n\n\\{x = \\text{arg}0, \\ y = \\text{arg}1\\}\n\nThe other expressions OpenModelica does not accept but the Modelica specification allows concern the list of function argument elements before a for expression, which is discussed before. JModelica and the Modelica specification allow a list of function arguments possibly expanded by a list of named arguments or a list of named arguments as the last example suggests. These differences arise from the additional possibilities that the function arguments offer.\n\nThe last constructs we interpret regarding the use of different simulation environments are component references, names, and named argument expressions.\n\nNamed Argument and Component References\n\nComponent references also model names in OpenModelica and JModelica. Names are more restricted than component references as they do not allow subscripts. The difference has already been discussed above. Writing code adhering to the names scheme will not cause problems within OpenModelica or JModelica. The differences that might cause problems are in the additional keyword \\texttt{operator} in OpenModelica and the missing optional subscript after the first identifier if the reference starts with a dot. Examples of component references OpenModelica accepts but JModelica does not are:\n\n\\texttt{.x[3:6] = overload(name list)}\n\nThe keyword \\texttt{operator} is used to model overloading of operators to which the Modelica Association dedicates an own section in its language specification document since Version 3.1. For the operator keyword, any operator, of relational, additive, or multiplicative nature, can be inserted and overloaded as a result. Overloading functions is not possible within JModelica \\cite{JModelica}. Overloading is supported by the Modelica specification but is not modeled within its grammar in the same way as OpenModelica does it.\n\nThe differences of the productions \\texttt{named_argument} and \\texttt{component_reference} resemble each other as the definition of the nonterminal \\texttt{named_argument} also involves the keyword \\texttt{operator} in OpenModelica but not in the Modelica specification and JModelica.\n\nThe considerations of the differences caused by the keyword \\texttt{operator} close this section of analyzing the results of the LCIs. We have taken a look at the meaning of the differences for the grammars, the overall relation, and the use of simulation environments with different grammars. The next section discusses the transformations used in the three LCIs conducted.\n\n5.2 Analysis of the Transformations\n\nThis section is subdivided into the summary of the programmed transformations (Subsection 5.2.1), an investigation of the unused operators (Subsection 5.2.2), and an analysis of the order of the transformations and the correctness of the result (Subsection 5.2.3).\n5.2. Analysis of the Transformations\n\n<table>\n<thead>\n<tr>\n<th>Transformation</th>\n<th>Modelica Specification vs. JModelica</th>\n<th>Modelica Specification vs. OpenModelica</th>\n<th>OpenModelica vs. JModelica</th>\n<th>Overall Number of Transformations</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>renameN(f, t)</td>\n<td>10</td>\n<td>2</td>\n<td>-</td>\n<td>12</td>\n</tr>\n<tr>\n<td>renameT(f, t)</td>\n<td>42</td>\n<td>46</td>\n<td>-</td>\n<td>88</td>\n</tr>\n<tr>\n<td>vertical(n)</td>\n<td>13</td>\n<td>11</td>\n<td>9</td>\n<td>24</td>\n</tr>\n<tr>\n<td>deyaccify(n)</td>\n<td>12</td>\n<td>10</td>\n<td>8</td>\n<td>20</td>\n</tr>\n<tr>\n<td>inline(n)</td>\n<td>20</td>\n<td>16</td>\n<td>14</td>\n<td>36</td>\n</tr>\n<tr>\n<td>factor(e, e)</td>\n<td>17</td>\n<td>14</td>\n<td>6</td>\n<td>23</td>\n</tr>\n<tr>\n<td>massage(e, e)</td>\n<td>11</td>\n<td>7</td>\n<td>22</td>\n<td>33</td>\n</tr>\n<tr>\n<td>extract(p)</td>\n<td>11</td>\n<td>7</td>\n<td>9</td>\n<td>11</td>\n</tr>\n<tr>\n<td>distribute(n)</td>\n<td>1</td>\n<td>10</td>\n<td>9</td>\n<td>11</td>\n</tr>\n<tr>\n<td>unfold(n)</td>\n<td>1</td>\n<td>2</td>\n<td>1</td>\n<td>4</td>\n</tr>\n<tr>\n<td>yaccify(p+)</td>\n<td>1</td>\n<td>1</td>\n<td>-</td>\n<td>1</td>\n</tr>\n<tr>\n<td>horizontal(n)</td>\n<td>2</td>\n<td>2</td>\n<td>1</td>\n<td>3</td>\n</tr>\n<tr>\n<td>removeV(p)</td>\n<td>2</td>\n<td>2</td>\n<td>5</td>\n<td>7</td>\n</tr>\n<tr>\n<td>introduce(p)</td>\n<td>-</td>\n<td>2</td>\n<td>3</td>\n<td>3</td>\n</tr>\n<tr>\n<td>fold(n)</td>\n<td>-</td>\n<td>-</td>\n<td>2</td>\n<td>1</td>\n</tr>\n<tr>\n<td>equate(n, n)</td>\n<td>-</td>\n<td>-</td>\n<td>2</td>\n<td>2</td>\n</tr>\n</tbody>\n</table>\n\n| Overall Number | 143 | 122 | 144 | 122 |\n| o | 7 | 2 | 2 | 294 |\n| m | 2 | 2 | 2 | 246 |\n\nTable 5.4: Overview of the Transformations Used in the three LCIs\n- **o**: overall number of transformations used in the respective LCI\n- **m**: number of transformations leading to the resolution of a nominal or structural mismatch\n\n5.2.1 Programmed Transformations\n\nThe convergence process has spawned the programming of close to 300 transformations. Table 5.4 lists the concrete numbers on which transformations have been used how many times. As mentioned before, some transformations are programmed to carve out the difference or to shorten the length of an expression during transformation programming by extracting an untouched part of a production and inlining it later. The overall number of transformations needed for the convergence of JModelica and OpenModelica with the Modelica specification is approximately the same, though, OpenModelica resembles the Modelica specification more in the general structure. This overall number consists of all transformations applied to the grammars as listed in Appendix E. The left column of each grammar column in the table, marked by the letter ‘o’ for overall, names the overall number of transformations. The number of transformations that aligned the grammars is 122 for the first two comparisons. For this number, we have taken out the transformations that have served to clarify differences, like the factorizing of the logical factors in the logical expressions of JModelica, or to simplify transformations by extracting part of a production. In other words, this number comprises the transformations that align the grammar sources by either dissolving an exclusive nonterminal or aligning production bodies of shared nonterminals. The right column, headed with the letter ‘m’ for mismatch, gives the number of transformations that have lead to dissolving a mismatch. The transformations mirror the different structures and ways of modeling a construct. OpenModelica has required a lot more massaging than JModelica whereas JModelica has needed almost thrice as much factoring.\nOpenModelica has shared two third of its defined nonterminals with the Modelica specification, resulting into fewer renamings of nonterminals compared to JModelica. JModelica has only one third of its nonterminal symbols in accordance with the Modelica specification, which requires more renamings. The comparison of JModelica and OpenModelica is based on the transformed grammars of the previous comparisons. These grammars have each had applied over 140 transformations themselves before the comparison against each other starts. As discussed in Section 4.5, most of the differences both grammars exhibit at this point towards the Modelica specification are bound to persist in this new LCI. The only transformation chain dissolving a nominal mismatch concerns function expressions. The other transformations reverse the introduction of names in both grammars for this comparison as the notion of names has only been introduced to accommodate the Modelica specification.\n\n5.2.2 Unused Operators\n\nAs mentioned before, XBGF includes 49 transformation operators. The transformations can be categorized in the following way; the number in brackets denotes how many operators we have used out of this category:\n\n- semantics-preserving operators: 21 (13)\n- semantics-changing operators: 18 (1)\n- decorative operators: 4 (0)\n- rename operators: 4 (2)\n- dump (not used)\n- reroot (not used)\n\nWe have used 16 of the 49 operators. As we have limited ourselves to semantics-preserving alterations of the grammar, we have mainly used semantics-preserving operators. The one semantics-changing operator we have used is removeV to eliminate choices in a production that do not carry any new information and as such, are redundant. The decorative operators account for features of the BGF itself, labels and selectors. As the Modelica grammar versions do not include labels and selectors, we did not need to introduce or eliminate any labels and selectors. The labels and selectors are also the reason why we have only used two out of four renaming operators. Labels and selectors can be renamed as well but without any present, the operators are unused. The grammar versions do not include specific roots, either, making a rerooting of any grammar version unnecessary. The operator dump halts the application of a transformation chain and dumps the current state of the grammar into a log file. As such, it can be used to debug XBGF files. Of the 21 semantics-preserving operators, we have used approximately two-thirds. The operators we have not used are abrige, detour, unchain, chain, eliminate, import, rassoc, and lassoc. The first two operators delete or introduce a reflexive production which we have not encountered or needed in the Modelica grammar versions. The operator unchain is a version of inlining and applicable if the production is only defined by one nonterminal and the defining nonterminal occurs only in this production. We could have used it, for example, when inlining the additive expressions in the arithmetic expressions in JModelica with the same result. The operator chain reverses such an unchaining operation. As we have never come to a point where a defined nonterminal has not been in use anymore, we have not employed the operator eliminate. The operator import imports a grammar which did not occur in our scenario. The transformation operators rassoc and lassoc replace an iterative production by a right or left associative repeating equivalent of the former. As we have transformed OpenModelica and JModelica towards the Modelica specification, which does not include such associative productions, the operators have not been used.\nThe patterns in a production allow a handful of transformations. Similar patterns call for similar transformations. In most cases, the chain of transformations needed to achieve a conversion of a production towards the targeted production is straightforward. Renamings dissolve nominal mismatches and varying styles for terminal symbols. In the case of OpenModelica, simple renamings of terminals has lead to eight converging productions. Recursive productions need to change into iterative productions which calls for the use of deyaccification. Similar structures can be identified between colliding definitions, the deviations then guide the transformations. Different positions of optionals or parts of sequences are dissolved by corresponding inlining and extracting. Some inlining or unchaining is necessary if constructs are modeled using more productions than the objective grammar, as has been the case with access expressions in JModelica.\n\n5.2.3 Order of the Application and Correctness of the Result\n\nThe order of the transformations within one XBGF file is determined by the intended effect on the production. The order between the different XBGF files is theoretically arbitrary. If the files impact different productions, the order does not matter. If the files impact the same productions, the order may not be arbitrary depending on the transformations. The reason for this dependence lays in the way of programming certain transformations. Unfortunately, only a handful transformations are fully automated. In case, a transformation needs the expression that should be changed and the expression to what the former should be transformed, conflicts are possible. For example, the operator \\texttt{factor} needs the changing expression and the expression to which the changing expression should be transformed specified. If the production affected has been changed by a renaming in the beginning and the new name is specified in the XBGF file for the factorizing transformation, we cannot change the order of the transformations as we would need to change the name in the XBGF file to the previous one. The effect on the production would be the same, whether we would apply a factorization first or a renaming. Thus, the order of application of the transformations does not matter in theory. The XBGF files might need to change as we might refer to expressions in the grammar that do not exist as such yet. The transformer would take the first expression and search for occurrences, which it would not be able to find, and therefore, replace nothing. This small example of a scenario where the order cannot simply be interchanged is a representative for any more complex scenarios of transformations where it might not be possible to change the order of application.\n\nIn most cases in our comparisons, the transformations programmed lead to the targeted version in a direct way. No shorter chain of transformations exist. Let us take a look at the names and component references of JModelica to investigate the transformations used. Programming the transformations for the comparison of the Modelica specification and JModelica, we had unfolded the definition of names into the component references. The component references had been defined solely by names. We could not have used the transformation operator \\texttt{unchain} as the names did not occur exclusively in the definition of the component references. We could not have inlined the names for the a similar reason. The names did occur in other places of the grammar though. We would have replaced every instance of the nonterminal \\texttt{name} with its definition, not just the one occurrence in the component references. We contemplated equating names and component references. For the time being, let us assume we want to keep only one of the two constructs. Which one does not matter, as we can rename one into the other at the end. As we have unfolded the names into the component references, we would have needed to equate the productions which would have lead to the replacement of one nonterminal with the other and the deletion of the former production. In a second alternative, we could also have used the transformation \\texttt{inline}, as described before, and then folded the component references in all the places where its definition occurred. A third alternative is to unfold the definition of component\nreferences, i.e. name, in the whole grammar and eliminate the production component_reference afterwards. For this way, we would actually have needed the operator eliminate, an operator unused in our work. In summary, in this scenario of merging names and component references, the transformation chain of unfold(name in component_reference); equate(); leads to the same result as the chain of inline(name); fold(component_reference); and the chain of unfold(component_reference); eliminate(component_reference);. But this scenario is a rare one as in most cases, we deal with the remodeling of structures and not the elimination of a production. We can conclude that the transformations applied lead to a common result and our result is indeed correct.\n\nThe last section of this chapter concentrates on observations made using LCI for comparing Modelica grammar versions.\n\n5.3 Experience with LCI\n\nLCI provides an infrastructure to the task of comparing two grammar versions. It allows for simple programmable transformations. The transformations are partly automated and applied to the grammars in an automated fashion. The infrastructure provides the user with a guideline to programming transformations in the attempt to converge different grammar sources. Apart from the core task, the SLPS provides the grammar engineer with several tools to visualize the work, e.g., scripts to convert a grammar into a parse tree or to pretty-print BGF grammars and XBGF transformations into a more readable format. The benefits of using a published approach is that the method has already been tested and approved. As the publishers state in various papers and as can be seen in their ongoing work on the topic [10, 36, 12, 35], the work is not finished and starting points for improvements of the tools exist. Working with the tool reveals some of those starting points. We continue with a brief look at a handful of those starting points. The points concern the tool in general, the setup and the output of the tool as well as enhancements of the transformations. Many of these ideas translate into future work.\n\nA very general objection is the necessity of the internal representation format. Though the argumentation why the use of the BGF is beneficial is conclusive, the use requires a user to become proficient to a certain stage in grammar extraction and conversion into BGF. As the BGF allows comparing different software artifacts with features that exceed the representation capability of textbook-style EBNF of context-free syntax, the additional effort pays off.\n\nFrom the general objection regarding BGF, we move to more specific ideas of improvement. From the standpoint of someone external to the development of the tool, the work lacks a comprehensive documentation or a user’s guide. Though the introduction to the SLPS claims that every topic within the suite is commented to the point that it should be possible to run the programs with the help of existing Makefiles, the setup of the tool and the start of the work is not fluent. To identify the necessary libraries and tools for LCI to be able to run takes time. To get an idea how to use the LCI, one needs to consult several papers. For the LCI to work, some folders need to exist, something that is not clearly visible from the error reports shown. A small introduction to the setup of the tool would be helpful. A comprehensive language manual exists for XBGF but a user’s guide on how to start and what to keep in mind would facilitate the initial steps within the LCI.\n\nThe next idea deals with an inconvenience one might have noticed during Chapter 4. Whenever we want more detailed information about the differences between two grammars, we need to call the comparator script directly. The LCI outputs status lines about the overall success of the different steps within the LCI. For the result of the comparison, it creates a file with a list of the nonterminals that are shared but collide in their respective definitions. In addition,\nthe generated diagrams at the end of the LCI might give clues about the differences. But the output of the comparator is not completely saved. Instead, it is discarded within the LCI. These comparator outputs contrast the colliding definitions and list the exclusive nonterminals. Even the definitions of the exclusive nonterminals could be of interest. Currently, they are not part of the output. This information can help in programming the transformations required for aligning the grammars without the need to always look up the definitions in different documents.\n\nAfter these suggestions concerning the LCI, the transformations receive attention. We revisit the grammar transformations and discuss scenarios that present a starting point for further automation of transformations and for suggesting transformations to the user of the LCI. Comparing the Modelica grammar versions needs mainly the transformations rename, factor and massage, vertical and deyaccify, extract, and inline. A simple example of ideas to automate transformations is the following. Similar situations call for identical sequences of transformations. A common combination has been the transformations vertical and deyaccify. Both need the nonterminal to whose production they are applied. The transformations could be combined to further automate the process. Another common scenario is the massaging of a choice of an epsilon and another expression into an optional expression. A script could take the nonterminal as input and convert all choices involving an epsilon into an optional. If this choice consists of more than two alternatives, the automated version might convert the alternatives into an optional choice expression consisting of all alternatives. A manually programmed massaging transformation would be needed if only parts of the alternatives should be transformed into an optional.\n\nThe transformation massage includes many possible transformations, which all can become tiresome to write as the transformation requires the expression to be transformed and the transformed version. In a complex grammar, these expressions may be rather large. The transformation factor faces a similar situation. A further automation of the programming of these transformations would be favorable. With the transformations massage and factor, we enter new scenarios, which lead to further ideas of improvement. These ideas would require even more work than the small automation approaches described previously. Given a certain pattern in the production, a handful of productions are applicable and reasonable. How to classify transformations as reasonable by a script may be even harder, but as a first step it might be feasible to suggest transformations for a production. As a starting point, the scope of the transformations suggested can be restricted to semantics-preserving transformations, and a tool or script outside of the LCI can take the grammar and the production name as input and suggest transformations for that production as output. For example, in case of a sequence with an inner choice, the tool can suggest a distribution. If the alternatives of a choice end on an identical expression, a factorization is applicable. The aforementioned transformation massage offers many possibilities for transformation. If programming a yaccification or deyaccification, the transformer already checks whether the input matches a “yaccify” pattern and replaces the input with the matching expression according to the pattern. In this case, code already exists to detect patterns. The basic idea behind suggestions of transformations is to detect patterns and suggest transformations applicable to these patterns. In a later stage, the tool might also generate the transformations, which would contribute to the efforts of further automation of the convergence process.\n\nThe considerations of further automation of language convergence marks the endpoint of this chapter on the evaluation of the results of the language convergence process. We have seen the implications of the differences on the languages generated by the grammars and the use of various simulation environments. Working with the LCI has lead to concrete ideas for improvement and future work. The body of the thesis is completed and we finish with a conclusion and a summary on future work.\nChapter 6\n\nConclusion\n\n6.1 Future Work\n\nThe language convergence process of the Modelica expressions in the grammars of the Modelica specification, the OpenModelica parser description, and the JModelica parser description results in several new questions and possible tasks. These questions and tasks regard both Modelica and the LCI. We start with the future work concerning Modelica and close with propositions for future work for the LCI.\n\nFirst, we would be interested in an LCI of the entire Modelica grammar, not just an excerpt of it. We could expand the statement concerning the relation of the grammars to the whole grammar and not only the expressions. A new LCI with a complete grammar can reveal new differences where programmers need to be careful if switching simulation environments. It might also help to further classify the difference between the OpenModelica grammar and the other two grammars about the referenced code and match expressions within the production `expression`. Additionally, we can extend the grammar sources by other commonly used simulation environments.\n\nThe encountered differences as a basis, maintainers and developers of the simulation environment could examine whether the differences are intended, and therefore, should be kept, or whether these differences are unintended and should be eliminated. If the differences are maintained, the user’s guide or manual could be updated to point to the areas where the simulation environment deviates from the Modelica specification.\n\nWe move from the field of grammar convergence to another area. Analyzing a grammar for a programming language almost automatically poses the question whether the grammar represents the language in a coherent way. We have already seen in the analysis of the differences that some productions represent constructs in a more precise way than others. One example are the names in Modelica in comparison to the component references in the other grammar versions. Another example is the way of modeling the function `initial()`. In a similar question, one might ask how much of what the grammar or the parser allows is accepted by a compiler. We have observed that the Modelica grammar allows a list of commas in the generation of output expression lists. A compiler might reject such an expression. Differences might always be present between what a parser and a compiler accepts. Nonetheless, a coherence should exist between a parser and a compiler just like between a parser and a language specification. A starting point for such an analysis would be the Modelica grammar, the point of reference for the simulation environments. The next paragraph focuses on ideas of improvement for the LCI.\n\nWe have discussed topics for future work in the context of the LCI in the previous chap-\n6.2 Conclusion\n\nThis thesis aims to answer the question whether different Modelica grammar versions agree. The grammar sources subject to investigation are the Modelica language specification, the OpenModelica parser, and the JModelica parser. The time frame of a Bachelor thesis allows only for the section “Expressions” of the Modelica specification and the corresponding productions in JModelica and OpenModelica to be part of the investigation. The means to answer the question is to compare the grammars. Based on the encountered differences, we transform the grammars. The process forms a compare/transform cycle until we cannot dissolve any more differences. The tool we have chosen to support us in our investigation is the Language Convergence Infrastructure developed by Ralf Lämmel and Vadim Zaytsev. To accommodate the workings of the tool, we have written extractors that convert the grammar sources in the internal representation format BGF. Fed with the corresponding configuration, the tool outputs a verdict on the convergence of the grammar sources. A framework of programmable grammar transformations is associated with the tool LCI. The framework contains transformations applicable to the BGF grammars. For the grammar sources to converge, we have programmed XBGF transformations. With the help of the LCI and the XBGF, we have aligned large parts of the grammars and carved out the remaining differences.\n\nThe result of the LCIs is that all grammar versions disagree and that no version is strictly more permissive or restrictive than the other versions. In summary and neglecting some differences, the grammars form the relation of OpenModelica being more permissive than Modelica being more permissive than JModelica. The differences result into several situations where a programmer needs to revise their code when presenting code adhering to the Modelica grammar to the simulation environments. In addition, one needs to exercise caution if switching from one simulation environment to the other.\n\nFuture work includes the extension of the comparison to the entire grammar and to other simulation environments, an analysis of the representativeness of the grammar for the language, and possible actions concerning the encountered differences. The LCI can be enhanced by a user’s guide, a more detailed output, and further automation activities.\nAppendix A\n\nGrammar Sources\n\nA.1 Modelica Specification\n\nexpression : simple_expression\n | \"if\" expression \"then\" expression { \"elseif\" expression \"then\" expression }\n | \"else\" expression\n\nsimple_expression : logical_expression [ \":\" logical_expression [ \":\" logical_expression ] ]\n\nlogical_expression : logical_term { \"or\" logical_term }\n\nlogical_term : logical_factor { \"and\" logical_factor }\n\nlogical_factor : [ \"not\" ] relation\n\nrelation : arithmetic_expression [ rel_op arithmetic_expression ]\n\nrel_op : \"<\" | \"<=\" | \"<\" | \">=\" | \"==\" | \"<>\"\n\narithmetic_expression : [ add_op ] term { add_op term }\n\nadd_op : \"+\" | \"-\" | \".+\" | \".-\"\n\nterm : factor { mul_op factor }\n\nmul_op : \"/\" | \".*\" | \"/.*\"\n\nfactor : primary [ (\".\" | \".\" ) primary ]\n\nprimary : \"UNSIGNED_NUMBER\"\n | \"STRING\"\n | \"false\"\n | \"true\"\n\n( name | \"der\" | \"initial\" ) function_call_args\n\ncomponent_reference\n\n[ \"output_expression_list \"]\n\n[ \"expression_list { \":\" expression_list } \"]\n\n[ \"function_arguments \"]\n\nend\n\nname : [ \".\" ] \"IDENT\" { \".\" \"IDENT\" }\n\ncomponent_reference :\nListing A.1: Modelica Specification Expressions\n\nA.2 JModelica\n\narray_subscripts: \"LBRACK\" subscript_list \"RBRACK\"\nsubscript_list: subscript\n| subscript_list \"COMMA\" subscript\nsubscript: \"COLON\" | exp\nannotation: \"ANNOTATION\" class_modification\nexp: simple_expression\n| if_exp\n| if_exp: \"IF\" exp \"THEN\" exp else_if_exp\nelse_if_exp: \"ELSEIF\" exp \"THEN\" exp else_if_exp\n| \"ELSE\" exp\nsimple_expression:\n| log_exp\n| log_exp \"COLON\" log_exp\n| log_exp \"COLON\" log_exp \"COLON\" log_exp\nlog_exp: log_exp \"OR\" log_exp\n| log_exp \"AND\" log_exp\n| \"NOT\" relation\nrelation:\n| artm_exp \"LT\" artm_exp\nA.2. JMODELICA\n\n```\n| artm_exp | \"LEQ\" artm_exp |\n| artm_exp | \"GT\" artm_exp |\n| artm_exp | \"GEQ\" artm_exp |\n| artm_exp | \"EQ\" artm_exp |\n| artm_exp | \"NEQ\" artm_exp |\n| artm_exp | additive_exp |\n\nadditive_exp:\n | multiplicative_exp |\n | additive_exp | \"PLUS\" multiplicative_exp |\n | additive_exp | \"MINUS\" multiplicative_exp |\n | additive_exp | \"DOTPLUS\" multiplicative_exp |\n | additive_exp | \"DOTMINUS\" multiplicative_exp |\n\nmultiplicative_exp:\n | unary_exp |\n | multiplicative_exp | \"MULT\" unary_exp |\n | multiplicative_exp | \"DIV\" unary_exp |\n | multiplicative_exp | \"DOTMULT\" unary_exp |\n | multiplicative_exp | \"DOTDIV\" unary_exp |\n\nunary_exp:\n | pow_exp |\n | \"MINUS\" unary_exp |\n | \"PLUS\" unary_exp |\n\npow_exp:\n | primary |\n | primary | \"POW\" primary |\n | primary | \"DOTPOW\" primary |\n\nprimary:\n | \"UNSIGNED\" |\n | \"UNSIGNED_INTEGER\" |\n | \"TRUE\" |\n | \"FALSE\" |\n | \"STRING\" |\n | access_expression |\n | der_expression |\n | LPAREN exp RPAREN |\n | function_call |\n | LBRAKC matrix RBRAKC |\n | LBRAKC function_arguments RBRAKC |\n | TIME |\n | END |\n\nfunction_call:\n | parse_access LPAREN function_arguments RPAREN |\n\npartial_function_call:\n | \"FUNCTION\" parse_access LPAREN function_arguments RPAREN |\n\nfunction_arguments:\n | exp FOR for_indices |\n | arg_List_p |\n | arg_List_p COMMA named_arguments |\n | named_arguments |\n\nnamed_arguments:\n | named_argument |\n | named_arguments COMMA named_argument |\n\nfunction_argument_exp:\n | exp |\n | partial_function_call |\n\nnamed_argument:\n | named_argument |\n | named_arguments EQUALS named_argument |\n\nmatrix:\n```\n### Listing A.2: JModelica Expressions\n\n```\nmatrix_row\n| matrix \"SEMICOLON\" matrix_row\nmatrix_row:\n exp\narg_list_p:\n function_argument_exp\n| arg_list_p \"COMMA\" function_argument_exp\ncomment:\n string_comment? annotation?\nstring_comment:\n \"STRING\"\n| string_comment \"PLUS\" \"STRING\"\naccess_expression:\nparse_access\n der_expression:\n \"DER\" \"LPAREN\" exp \"RPAREN\"\nparse_access:\n parse_access_loc\n| \"DOT\" first_class_access\nparse_access_loc:\n parse_access_single\n| parse_access_single \"DOT\" parse_access_loc\nfirst_class_access:\n class_access_single\n| class_access_single \"DOT\" parse_access_loc\nparse_access_single:\n \"ID\" array_subscripts?\nclass_access_single:\n \"ID\"\n\narray_subscripts:\n \"[\" subscript (\",\" subscript)* \"]\nsubscript:\n \":\" | expression\nannotation:\n \"annotation\" class_modification\nexpression:\n simple_expression\n| \"if\" expression \"then\" expression (\"elseif\" expression \"then\" expression)* \"else\" expression\nsimple_expression:\n logical_expression (\";\" logical_expression (\";\" logical_expression)?)?\nlogical_expression:\n logical_factor (\"or\" | \"and\") logical_expression*\nrelation:\n arithmetic_expression (rel_op arithmetic_expression)?\narithmetic_expression:\n term (add_op term)*\nterm:\n factor (mul_op factor)*\nfactor:\n (\"-\" | \"+\")* primary (\"-\" | \"+\") primary?\nprimary:\n \"UNSIGNED_NUMBER\"\n| \"true\"\n| \"false\"\n| \"STRING\"\n| component_reference\n| \"der\" (\" expression \")\n```\n\n---\n\nAPPENDIX A. GRAMMAR SOURCES\n\n---\nListing A.3: Transformed JModelica Expressions\n\n```\n| \"(\" output_expression_list \")\"\n| name function_call_args\n| \"(\" expression_list (\":\" expression_list) \"\")\"\n| [\"(\" function_arguments \")\"\n| \"end\"\n\noutput_expression_list:\n expression\nfunction_call_args:\n \nfunction_arguments:\n expression \"for\" for_indices\n function_argument (\",\" function_argument)\"\n function_argument (\",\" function_argument) \",\" named_arguments\n named_arguments\n named_argument (\",\" named_arguments)\"\n\nfunction_argument:\n expression\n \"function\" name (\" function_arguments? \")\"\n\nnamed_argument:\n \"IDENT\" == function_argument\nexpression_list:\n expression (\",\" expression)*\n\ncomment:\n string_comment annotation?\n\ncomponent_reference:\n \"IDENT\" array_subscripts? (\".\" \"IDENT\" array_subscripts?)\"\n \nname:\n \"IDENT\" array_subscripts? (\".\" \"IDENT\" array_subscripts?)\"\n \nrel_op:\n \"<\" | \"<=\" | \">\" | \">=\" | \"==\" | \"<>\"\nadd_op:\n \"-\" | \"+\" | \".+\" | \",-\"\nmul_op:\n \"*\" | \"/\" | \".*\" | \"/.\"\n\nstring_comment:\n (\"STRING\" (\"+\" \"STRING\")*)\n\nlogical_factor:\n \"not\"? relation\n\narithmetic_expression (rel_op arithemetic_expression)?\narithmetic_expression:\n```\n\nA.2. JMODELICA\nAPPENDIX A. GRAMMAR SOURCES\n\nListing A.4: Transformed JModelica Expressions after LCI with OpenModelica\nA.3 OpenModelica\n\nexpression:\n if_expression\n | simple_expression\n | code_expression\n | part_eval_function_expression\n | match_expression\n\npart_eval_function_expression:\n \"FUNCTION\" component_reference function_call\n\nif_expression:\n \"IF\" expression \"THEN\" expression elseif_expression_list? \"ELSE\" expression\nelseif_expression_list:\n elseif_expression elseif_expression_list?\nelseif_expression:\n \"ELSEIF\" expression \"THEN\" expression\n\nsimple_expression:\n simple_expr (\"COLONCOLON\" simple_expression)?\n | \"IDENT\" \"AS\" simple_expression\n\nsimple_expr:\n logical_expression (\"COLON logical_expression (\"COLON logical_expression)\")?\n\nlogical_expression:\n logical_term (\"T\\(\\text{OR}\\) logical_term\")\n\nlogical_term:\n logical_factor (\"T\\(\\text{AND}\\) logical_factor\")\n\nlogical_factor:\n \"T\\(\\text{NOT}\\)? relation\n\nrelation:\n arithmetic_expression ((\"LESS\" | \"LESSEQ\" | \"GREATER\" | \"GREATEREQ\" | \"EQEQ\" | \"LESSGT\") arithmetic_expression)?\n\narithmetic_expression:\n unary_arithmetic_expression (\"PLUS\" | \"MINUS\" | \"PLUS\\text{EW}\" | \"MINUS\\text{EW}\") term*\n\nunary_arithmetic_expression:\n \"PLUS\" term\n | \"MINUS\" term\n | \"PLUS\\text{EW}\" term\n | \"MINUS\\text{EW}\" term\n\nterm:\n factor ((\"STAR\" | \"SLASH\" | \"STAR\\text{EW}\" | \"SLASH\\text{EW}\") factor)*\n\nfactor:\n primary ((\"POWER\" | \"POWER\\text{EW}\") primary)?\n\nprimary:\n \"UNSIGNED\\text{INTEGER}\"\n | \"UNSIGNED\\text{REAL}\"\n | \"STRING\"\n | \"T\\(\\text{FALSE}\\\"\n | \"T\\(\\text{TRUE}\\\"\n | component_reference_function_call\n | \"DER\" function_call\n | \"LPAR\" output_expression_list\n | \"LBRACK\" matrix_expression_list \"RBRACK\"\n | \"LBRACE\" for_or_expression_list \"RBRACE\"\n | \"T\\(\\text{END}\\\"\n\nmatrix_expression_list:\n expression_list (\"SEMICOLON\" matrix_expression_list)?\n\ncomponent_reference_function_call:\n component_reference_function_call\n | \"INITIAL\" \"LPAR\" \"RPAR\"\n\ncomponent_reference:\n \"DOT\"? component_reference2\nListing A.5: OpenModelica Expressions\n\nexpression:\n \"if\" expression \"then\" expression (\"elseif\" expression \"then\" expression)* \"else\" expression\n | (simple_expression \":=\") | (\"IDENT\" \"as\")* simple_expression\n | code_expression\n | part_eval_function_expression\n | match_expression\n\npart_eval_function_expression:\n \"function\" name function_call_args\n\nsimple_expression:\n logical_expression (\":=\" logical_expression (\":=\" logical_expression)?)\nlogical_expression:\n logical_term (\"or\" logical_term)*\nlogical_term:\n logical_factor (\"and\" logical_factor)*\n\nlogical_factor:\n \"not\"? relation\nrelation:\n arithmetic_expression (rel_op arithmetic_expression)?\n\narithmetic_expression:\n add_op? term (add_op term)*\nterm:\n factor (mul_op factor)*\nA.3. OPENMODELICA\n\nListing A.6: Transformed OpenModelica Expressions\n\nexpression:\n \"if\" expression \"then\" expression (\"elseif\" expression \"then\" expression)* \"else\" expression\n | ((simple_expression \"::\") | (\"IDENT\" \"as\"))* simple_expression\nAPPENDIX A. GRAMMAR SOURCES\n\n| code_expression\n| part_eval_function_expression\n| match_expression\npart_eval_function_expression:\n \"function\" component_reference function_call_args\nsimple_expression:\n logical_expression (\":\" logical_expression (\":\" logical_expression)?)?\nlogical_expression:\n logical_term (\"or\" logical_term)*\nlogical_term:\n logical_factor (\"and\" logical_factor)*\nlogical_factor:\n \"not\"? relation\nrelation:\n arithmetic_expression (rel_op arithmetic_expression)?\narithmetic_expression:\n add_op? term (add_op term)*\nterm:\n factor (mul_op factor)*\nfactor:\n primary (\"\" | \".\") primary)?\nprimary:\n (component_reference | \"der\") function_call_args\n \"UNSIGNED_NUMBER\"\n \"STRING\"\n \"false\"\n \"true\"\n component_reference\n \"initial\" \"(\" \")\"\n \"(\" output_expression_list \")\"\n \"(\" expression_list \";\" expression_list \")\"\n \"(\" for_or_expression_list \")\"\n \"end\"\ncomponent_reference:\n \".\"? (\"IDENT\" | \"operator\") array_subscripts? (\".\" (\"IDENT\" | \"operator\")\narray_subscripts?)*\nfunction_call_args:\n \"(\" function_arguments? \")\"\nfor_or_expression_list:\n (function_argument (\"\",\"\" function_argument \",\")* function_argument?)\n (\"for\" for_indices)?\nnamed_arguments:\n named_argument (\",\" named_arguments)?\nnamed_argument:\n (\"IDENT\" | \"operator\") \"+\" function_argument\nexpression_list:\n expression (\"\",\"\" expression)*\narray_subscripts:\n \"(\" subscript (\",\" subscript)* \")\"\nsubscript:\n expression | \".:\"\ncomment:\n string_comment annotation?\nstring_comment:\n (\"STRING\" (\"+\" \"STRING\")*)?\nannotation:\n \"annotation\" class_modification\nrel_op:\n \"<\" | \"<=\" | \">\" | \">=\" | \">=\" | \">>\nmul_op:\n \"*\" | \"/\" | \".*\" | \"/.\"\nadd_op:\noutput_expression_list:\n expression? (\",\" expression?)\n function_arguments:\n named_arguments\n | function_argument (\"\",\" (function_argument \",\")* function_argument?) | (\"for\" for_indices))? named_arguments?\nfunction_argument:\n expression\n## Appendix B\n\n### BGF\n\n#### B.1 BGF Grammar\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>grammar:</td>\n<td>root :: nonterminal* production*</td>\n</tr>\n<tr>\n<td>production:</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n - label :: label? nonterminal :: nonterminal expression |\n| expression: | \n - epsilon :: ε |\n| | \n - empty :: ε |\n| | \n - value :: value |\n| | \n - any :: ε |\n| | \n - terminal :: terminal |\n| | \n - nonterminal :: nonterminal |\n| | \n - selectable :: (selector :: selector expression) |\n| | \n - sequence :: (expression+) |\n| | \n - marked :: expression |\n| | \n - choice :: (expression+) |\n| | \n - optional :: expression |\n| | \n - plus :: expression |\n| | \n - star :: expression |\n| value: | \n - int :: ε |\n| | \n - string :: ε |\n| label: | STR |\n| nonterminal: | STR |\n| selector: | STR |\n| terminal: | STR |\n\nListing B.1: BGF Grammar\nB.2 Example Grammar\n\n```\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<bgf:grammar xmlns:bgf=\"http://planet-sl.org/bgf\">\n <bgf:production>\n <nonterminal>subscript</nonterminal>\n <bgf:expression>\n <choice>\n <bgf:expression>\n <nonterminal>expression</nonterminal>\n </bgf:expression>\n <terminal>::</terminal>\n </choice>\n <bgf:expression>\n <nonterminal>expression</nonterminal>\n </bgf:expression>\n </bgf:expression>\n </bgf:production>\n</bgf:grammar>\n```\n\nListing B.2: Example Modelica Specification BGF\n\n```\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<bgf:grammar xmlns:bgf=\"http://planet-sl.org/bgf\">\n <bgf:production>\n <nonterminal>subscript</nonterminal>\n <bgf:expression>\n <choice>\n <bgf:expression>\n <terminal>::</terminal>\n </bgf:expression>\n <nonterminal>exp</nonterminal>\n </choice>\n </bgf:expression>\n </bgf:production>\n</bgf:grammar>\n```\n\nListing B.3: Example JModelica BGF\n## Appendix C\n\n### LCF\n\n#### C.1 LCF Grammar\n\n<table>\n<thead>\n<tr>\n<th>Scenario:</th>\n<th>shortcut* tools source+ target+ testset*</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Shortcut:</td>\n<td>name::id expansion::xstring</td>\n</tr>\n<tr>\n<td>Tools:</td>\n<td>transformer::tool comparator::tool validator::tool? generator*</td>\n</tr>\n<tr>\n<td>Tool:</td>\n<td>grammar::xstring tree::xstring?</td>\n</tr>\n<tr>\n<td>Generator:</td>\n<td>name::id command::xstring</td>\n</tr>\n<tr>\n<td>Testset:</td>\n<td>name::id command::xstring</td>\n</tr>\n<tr>\n<td>Source:</td>\n<td>name::id derived? source-grammar source-tree? test-set::refid*</td>\n</tr>\n<tr>\n<td>Derived:</td>\n<td>from::refid using::string</td>\n</tr>\n<tr>\n<td>Source-grammar:</td>\n<td>extraction::xstring parsing::xstring? evaluation::xstring?</td>\n</tr>\n<tr>\n<td>Source-tree:</td>\n<td>extraction::xstring evaluation::xstring?</td>\n</tr>\n<tr>\n<td>Target:</td>\n<td>name::id branch+</td>\n</tr>\n<tr>\n<td>Branch:</td>\n<td>input::refid preparation::phase? nominal-matching::phase? structural-matching::phase? (extension::phase</td>\n</tr>\n<tr>\n<td>Phase:</td>\n<td>step::{perform-transformation::string</td>\n</tr>\n<tr>\n<td>Automated-transformation:</td>\n<td>method::refid result::string</td>\n</tr>\n</tbody>\n</table>\n\nListing C.1: LCF Grammar\nC.2 Example Grammar\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<lf:configuration xmlns:lf=\"http://planet-sl.org/lcf\">\n <shortcut>\n <name>impl</name>\n <expansion>../</expansion>\n </shortcut>\n <shortcut>\n <name>srcs</name>\n <expansion>impl</expansion>/srcs</expansion>\n </shortcut>\n <shortcut>\n <name>extraction</name>\n <expansion>impl</expansion>/extraction</expansion>\n </shortcut>\n <shortcut>\n <name>slps</name>\n <expansion>...</expansion>/slps-master</expansion>\n </shortcut>\n <shortcut>\n <name>tools</name>\n <expansion>slps</expansion>/shared/tools</expansion>\n </shortcut>\n <tools>\n <transformer>\n <grammar>tools</grammar>/xhgf</transformer>\n </transformer>\n <comparator>\n <grammar>tools</grammar>/gdt</comparator>\n </tools>\n <source>\n <name>leaf-expr-j</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/j2bgf <expand>srcs</expand>/jmod/leaf-expr-j.txt\n </extraction>\n </grammar>\n </source>\n <source>\n <name>leaf-expr-m</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/m2bgf <expand>srcs</expand>/mod/leaf-expr-m.txt\n </extraction>\n </grammar>\n </source>\n <target>\n <name>node</name>\n <branch>\n <input>leaf-expr-j</input>\n </branch>\n <branch>\n <input>leaf-expr-m</input>\n </branch>\n </target>\n</lf:configuration>\n```\n<lcf:configuration xmlns:lcf=\"http://planet-sl.org/lcf\">\n <shortcut>\n <name>impl</name>\n <expansion>impl</expansion>\n </shortcut>\n <shortcut>\n <name>srcs</name>\n <expansion><expand>impl</expand>/srcs</expansion>\n </shortcut>\n <shortcut>\n <name>extracts</name>\n <expansion>extracts</expansion>\n </shortcut>\n <shortcut>\n <name>slps</name>\n <expansion>slps</expansion>\n </shortcut>\n <shortcut>\n <name>tools</name>\n <expansion>slps</expansion>/shared/tools\n </shortcut>\n <transformation>\n <grammar>tools</grammar>\n <transformer>xbgf</transformer>\n </transformation>\n <transformation>\n <grammar>tools</grammar>\n <transformer>gdt</transformer>\n </transformation>\n <source>\n <name>leaf-expr-j</name>\n <grammar>\n <extraction>\n <expand>extracts</expand>/j2bfg <expand>srcs</expand>/jmod/leaf-expr-j.txt\n </extraction>\n </grammar>\n </source>\n <source>\n <name>leaf-expr-m</name>\n <grammar>\n <extraction>\n <expand>extracts</expand>/m2bfg <expand>srcs</expand>/mod/leaf-expr-m.txt\n </extraction>\n </grammar>\n </source>\n <target>\n <name>node</name>\n <branch>\n <input>leaf-expr-j</input>\n <structural-matching>\n <perform>rename-j-leaf</perform>\n </structural-matching>\n </branch>\n </target>\n</lcf:configuration>\nAPPENDIX C. LCF\n\nListing C.3: Updated Example LCF\n\nC.3 Modelica Specification vs. JModelica\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n<lf:configuration xmlns:lf=\"http://planet-sl.org/lcf\">\n <shortcut>\n <name>impl</name>\n </shortcut>\n <shortcut>\n <name>srs</name>\n </shortcut>\n <shortcut>\n <name>slps</name>\n </shortcut>\n <shortcut>\n <name>tools</name>\n </shortcut>\n <tools>\n <transformer>\n <grammar>\n <expand>tools/xbgf/grammar</expand>\n </grammar>\n </transformer>\n <transformer>\n <grammar>\n <expand>tools/gdt/grammar</expand>\n </grammar>\n </transformer>\n </tools>\n <source>\n <name>expr-j</name>\n <extract>\n <expand>expression</expand>/j2bgf <expand>srs</expand>/jmod/expr-j.txt\n </extract>\n </source>\n <source>\n <name>expr-mc</name>\n <extract>\n <expand>expression</expand>/m2bgf <expand>srs</expand>/mod/expr-m.txt\n </extract>\n </source>\n</lf:configuration>\n```\nListing C.4: Initial LCF for the Modelica Specification vs. JModelica\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n<lcf:configuration xmlns:lcf=\"http://planet-sl.org/lcf\">\n <shortcut>\n <name>impl</name>\n <expansion>../</expansion>\n </shortcut>\n <shortcut>\n <name>srcs</name>\n <expansion>impl</expansion>/srcs</expansion>\n </shortcut>\n <shortcut>\n <name>extrac</name>\n <expansion>impl</expansion>/extrac</expansion>\n </shortcut>\n <shortcut>\n <name>slps</name>\n <expansion>../slps-master</expansion>\n </shortcut>\n <shortcut>\n <name>tools</name>\n <expansion>/slps</expansion>/shared/tools</expansion>\n </shortcut>\n <shortcut>\n <name>tools</name>\n <grammar><expand>tools</expand>/xbgf</grammar>\n </shortcut>\n <shortcut>\n <grammar><expand>tools</expand>/gdt</grammar>\n </shortcut>\n <source>\n <name>expr-j</name>\n <grammar><expand>extrac</expand>/j2bgf <expand>srcs</expand>/jmod/expr-j.txt</grammar>\n </source>\n <source>\n <name>expr-m</name>\n <grammar><expand>extrac</expand>/m2bgf <expand>srcs</expand>/mod/expr-m.txt</grammar>\n </source>\n</lcf:configuration>\n```\nListing C.5: Final LCF for the Modelica Specification vs. JModelica\n\nC.4 Modelica Specification vs. OpenModelica\nListing C.6: Initial LCF for the Modelica Specification vs. OpenModelica\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<lcf:configuration xmlns:lcf=\"http://planet-sl.org/lcf\">\n <shortcut>\n <name>impl</name>\n <expansion>...</expansion>\n </shortcut>\n <shortcut>\n <name>src</name>\n <expansion>impl</expansion>/srcs</expansion>\n </shortcut>\n <shortcut>\n <name>extraction</name>\n <expansion>impl</expansion>/extraction</expansion>\n </shortcut>\n <shortcut>\n <name>slps</name>\n <expansion>...</expansion>/slps-master</expansion>\n</lcf:configuration>\n```\n<shortcut/>\n <shortcut>\n <name>tools</name>\n <expansion>expand</expansion>/shared/tools/<expansion>\n </shortcut>\n\n<tools>\n <transformer>\n <grammar>expand</grammar>/xbgf/grammar\n </transformer>\n <transformer>\n <grammar>expand</grammar>/gdt/grammar\n </transformer>\n</tools>\n\n<source>\n <name>expr-oc</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/o2bgf <expand>srcs</expand>/omod/expr-oc.g\n </extraction>\n </grammar>\n</source>\n\n<source>\n <name>expr-mc</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/m2bgf <expand>srcs</expand>/mod/expr-m.txt\n </extraction>\n </grammar>\n</source>\n\n<target>\n <name>target</name>\n <branch>\n <input>expr-oc</input>\n <nominal-matching>\n <perform>renameT-oc</perform>\n </nominal-matching>\n <structural-matching>\n <perform>sub-list-inline</perform>\n <perform>exp-list-massage</perform>\n <perform>rel-op-extract</perform>\n <perform>mul-op-extract</perform>\n <perform>una-inline</perform>\n <perform>ifexp-inline</perform>\n <perform>matrix-inline</perform>\n <perform>ref-align</perform>\n <perform>for-or-align</perform>\n <perform>fct-align</perform>\n <perform>call-inline</perform>\n <perform>part</perform>\n <perform>smp-inline</perform>\n <perform>eliminate-oc</perform>\n </structural-matching>\n </branch>\n <branch>\n <input>expr-mc</input>\n </branch>\n</target>\n\n</lcf:configuration>\nC.5 OpenModelica vs. JModelica\n\nListing C.7: Final LCF for the Modelica Specification vs. OpenModelica\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n<lcf:configuration xmlns:lcf=\"http://planet-sl.org/lcf\">\n <shortcut>\n <name>impl</name>\n <expansion>../</expansion>\n </shortcut>\n <shortcut>\n <name>bgf</name>\n <expansion><expand>impl</expand>/lcf/bgfc/expansion>\n </shortcut>\n <shortcut>\n <name>extraction</name>\n <expansion><expand>impl</expand>/extraction/expansion>\n </shortcut>\n <shortcut>\n <name>slps</name>\n <expansion>.././slps-master/shared/tools/expansion>\n </shortcut>\n <tools>\n <grammar><expand>tools</expand>/xbgf/grammar>\n <transformer>\n <comparator>\n <grammar><expand>tools</expand>/gdt/grammar>\n <source>\n <name>tgt-j</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/copybgf <expand>bgf</expand>/target-j.bgf\n </extraction>\n </grammar>\n <source>\n <name>tgt-o</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/copybgf <expand>bgf</expand>/target-o.bgf\n </extraction>\n </grammar>\n </source>\n </comparator>\n </transformer>\n </grammar>\n </tools>\n <target>\n <name>target</name>\n <branch>\n <input>tgt-j</input>\n </branch>\n <branch>\n <input>tgt-o</input>\n </branch>\n </target>\n</lcf:configuration>\n```\nListing C.8: Initial LCF for OpenModelica vs. JModelica\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<lcf:configuration xmlns:lcf=\"http://planet-sl.org/lcf\">\n <shortcut>\n <name>impl</name>\n <expansion>..</expansion>\n </shortcut>\n <shortcut>\n <name>bgf</name>\n <expansion>impl</expansion>/lcf/bgf</expansion>\n </shortcut>\n <shortcut>\n <name>extraction</name>\n <expansion>impl</expansion>/extraction</expansion>\n </shortcut>\n <shortcut>\n <name>slps</name>\n <expansion>...</expansion>/slps-master</expansion>\n </shortcut>\n <shortcut>\n <name>tools</name>\n <expansion>slps</expansion>/shared/tools</expansion>\n </shortcut>\n <tools>\n <transformer>\n <grammar>tools</grammar>/xbgf</grammar>\n </transformer>\n <comparator>\n <grammar>tools</grammar>/gdt</grammar>\n </comparator>\n </tools>\n <source>\n <name>tgt−j</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/copybgf <expand>bgf</expand>/target−j.bgf\n <extraction>\n </grammar>\n </source>\n <source>\n <name>tgt−o</name>\n <grammar>\n <extraction>\n <expand>extraction</expand>/copybgf <expand>bgf</expand>/target−o.bgf\n <extraction>\n </grammar>\n </source>\n <target>\n <name>target</name>\n <branch>\n <input>tgt−j</input>\n <structural−matching>\n <perform>elim−name−j</perform>\n <perform>tgt−refactor</perform>\n </branch>\n </target>\n</lcf:configuration>\n```\n<table>\n<thead>\n<tr>\n<th>Listing C.9: Final LCF for OpenModelica vs. JModelica</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>60</td>\n</tr>\n<tr>\n<td><structural-matching></td>\n</tr>\n<tr>\n<td></branch></td>\n</tr>\n<tr>\n<td><branch></td>\n</tr>\n<tr>\n<td><input>tgt-0</input></td>\n</tr>\n<tr>\n<td><structural-matching></td>\n</tr>\n<tr>\n<td><perform>elim-name-o</perform></td>\n</tr>\n<tr>\n<td></structural-matching></td>\n</tr>\n</tbody>\n</table>\nAppendix D\n\nComparator Output\n\nD.1 Modelica Specification vs. JModelica\n\nNames of defined nonterminals differ:\n\n- Intersection | array_subscripts, subscript, annotation, simple_expression, relation, primary, function_arguments, named_arguments, named_argument, comment, string_comment |\n- bgf/expr-j.bgf only: [subscript_list, exp, if_exp, else_if_exp, log_exp, artm_exp, additive_exp, multiplicative_exp, unary_exp, pow_exp, function_call, partial_function_call, function_argument_exp, named_argument_id, matrix, matrix_row, arg_list_p, access_expression, der_expression, parse_access, parse_access_loc, first_class_access, parse_access_single, class_access_single ]\n- bgf/expr-m.bgf only: [expression, logical_expression, logical_term, logical_factor, rel_op, arithmetic_expression, add_op, term, mul_op, factor, name, component_reference, function_call_args, function_argument, output_expression_list, expression_list ]\n\nComparisons per (common) nonterminal:\n\n- Fail (1/1): array_subscripts.\n - [] : (t(LBRACK), n(subscript_list), t(RBRACK))\n vs.\n - [] : (t(ARRAY), n(subscript_list))\n- Fail (1/1): subscript.\n - [] : (t(:), n(exp))\n vs.\n - [] : (t(ANNOTATION), n(class_modification))\n- Fail (1/1): simple_expression.\n - [] : (n(log_exp), (n(log_exp), t(COLON), n(log_exp)), (n(log_exp), t(COLON), n(log_exp)))\n vs.\n - [] : (n(logical_expression), ?(t(:), n(logical_expression)))\n- Fail (1/1): relation.\nAPPENDIX D. COMPARATOR OUTPUT\n\nListing D.1: Initial Comparator Output of the Modelica Specification vs. JModelica\n\n- \\[\\ldots\\] \\{(\\{[n(\\text{arithmetic\\_expression})], (\\{[n(\\text{rel\\_op})], n(\\text{arithmetic\\_expression}))\\} )\\} \\]\n \\hspace{1cm} vs.\n- \\[\\ldots\\] \\{(\\{[n(\\text{arithmetic\\_expression})], (\\{[n(\\text{rel\\_op})], n(\\text{arithmetic\\_expression}))\\} )\\} \\]\n \\hspace{1cm} Fail (1/1): primary.\n- \\[\\ldots\\] \\{(t(\\text{UNSIGNED\\_NUMBER}), t(\\text{UNSIGNED\\_INTEGER}), t(\\text{TRUE}), t(\\text{FALSE}), t(\\text{STRING}), n(\\text{access\\_expression}), n(\\text{der\\_expression})) \\}, \\{(t(\\text{LPAREN}), n(\\text{exp}), t(\\text{RPAREN}))\\}, \\{(n(\\text{function\\_call})), \\{(t(\\text{LBRACK}), n(\\text{matrix})), t(\\text{RBRACK}))\\}, \\{(t(\\text{LBRACE}), n(\\text{function\\_arguments})), t(\\text{RBRACE}))\\}, t(\\text{TIME}), t(\\text{END})\\}\n \\hspace{1cm} vs.\n- \\[\\ldots\\] \\{(t(\\text{UNSIGNED\\_NUMBER}), t(\\text{STRING}), t(\\text{false}), t(\\text{true})), \\{(n(\\text{name}), t(\\text{der}), t(\\text{initial})), n(\\text{component\\_reference}), \\{(t()\\}, n(\\text{output\\_expression\\_list}), t(\\text{()}))\\}, \\{(t()\\}, n(\\text{expression\\_list}), \\{*, \\{t()\\}, n(\\text{expression\\_list}\\}, t(\\text{()})\\}, \\{(t()\\}, n(\\text{function\\_arguments})), t(\\text{()})\\}, t(\\text{end})\\}\n \\hspace{1cm} Fail (1/1): function\\_arguments.\n- \\[\\ldots\\] \\{(n(\\text{exp}), t(\\text{FOR}), n(\\text{for\\_indices}))\\}, n(\\text{arg\\_list\\_p}), \\{(n(\\text{arg\\_list\\_p}), t(\\text{COMMA}), n(\\text{named\\_arguments}))\\}\n \\hspace{1cm} Fail (1/1): named\\_arguments.\n- \\[\\ldots\\] \\{n(\\text{named\\_argument}), \\{n(\\text{named\\_arguments}), t(\\text{COMMA}), n(\\text{named\\_arguments})\\}\\}\n \\hspace{1cm} vs.\n- \\[\\ldots\\] \\{n(\\text{named\\_argument}), \\{\\{t()\\}, n(\\text{named\\_arguments})\\}\\}\n \\hspace{1cm} Fail (1/1): named\\_argument.\n- \\[\\ldots\\] \\{n(\\text{named\\_argument}), t(\\text{EQUALS}), n(\\text{function\\_argument\\_exp})\\}\n \\hspace{1cm} vs.\n- \\[\\ldots\\] \\{n(\\text{string\\_comment}), \\{n(\\text{annotation})\\}\\}\n \\hspace{1cm} Fail (1/1): comment.\n- \\[\\ldots\\] \\{n(\\text{string\\_comment}), \\{n(\\text{annotation})\\}\\}\n \\hspace{1cm} vs.\n- \\[\\ldots\\] \\{n(\\text{string\\_comment}), \\{n(\\text{string\\_comment}), t(\\text{PLUS}), t(\\text{STRING})\\}\\}\n \\hspace{1cm} Fail (1/1): string\\_comment.\n- \\[\\ldots\\] \\{(t(\\text{STRING}), \\{\\{t()\\}, n(\\text{string\\_comment})\\}\\}\n \\hspace{1cm} vs.\n- \\[\\ldots\\] \\{(t(\\text{STRING}), \\{\\{t()\\}, t(\\text{STRING})\\}\\})\n \\hspace{1cm} Roots agree.\n\n- Names of defined nonterminals differ.\n - Intersection \\{array\\_subscripts, subscript, annotation, expression, simple\\_expression, logical\\_expression, relation, arithmetic\\_expression, term, factor, primary, output\\_expression\\_list, function\\_call\\_args, function\\_arguments, named\\_arguments, function\\_argument, named\\_argument, expression\\_list, comment, component\\_reference, name, rel\\_op, add\\_op, mul\\_op, string\\_comment, logical\\_factor\\}\n - bgf/expr->\\text{rename}.2, subscr.\\text{ifexp}.\\text{smpexp}.rel.\\text{extract}.\\text{message}.\\text{artm}.\\text{extract}.\\text{matrix}.access.named.fct.2.eliminate.refactor.bgf\n - bgf/expr-m.bgf\n\n- virtualbox:˜/Dokumente/impl/ICF$../.slps-master/shared/tools/gdt bgf/expr\n - j.rename.2, subscr.\\text{ifexp}.\\text{smpexp}.\\text{rel}.\\text{extract}.\\text{message}.\\text{artm}.\\text{extract}.\\text{matrix}.access.named.fct.2.eliminate.refactor.bgf\n - Normalizing bgf/expr->\\text{rename}.2, subscr.\\text{ifexp}.\\text{smpexp}.rel.\\text{extract}.\\text{message}.\\text{artm}.\\text{extract}.\\text{matrix}.access.named.fct.2.eliminate.refactor.bgf\n - Normalizing bgf/expr-m.bgf\n\n- Diffing bgf/expr->\\text{rename}.2, subscr.\\text{ifexp}.\\text{smpexp}.rel.\\text{extract}.\\text{message}.\\text{artm}.\\text{extract}.\\text{matrix}.access.named.fct.2.eliminate.refactor.bgf and bgf/expr-m.bgf\n\n- VirtualBox:˜/Dokumente/impl/ICF$../.slps-master/shared/tools/gdt bgf/expr\n- j.rename.2, subscr.\\text{ifexp}.\\text{smpexp}.\\text{rel}.\\text{extract}.\\text{message}.\\text{artm}.\\text{extract}.\\text{matrix}.access.named.fct.2.eliminate.refactor.bgf\nD.1. MODELICA SPECIFICATION VS. JMODELICA\n\nComparisons per (common) nonterminal:\n\n- Ok: array_subscripts.\n- Ok: subscript.\n- Ok: annotation.\n- Ok: expression.\n- Ok: simple_expression.\n- Fail (1/1): logical_expression.\n - [] , ( [ [ n ( logical_factor ) , * ( , ( [ [ t ( or ) , t ( and ) ] ) ) , n ( logical_expression ) ] ) ] )\n vs.\n - [] , ( [ [ n ( logical_term ) , * ( , ( [ [ t ( or ) , n ( logical_term ) ] ) ) ] ) ] )\n - Ok: relation.\n- Fail (1/1): arithmetic_expression.\n - [] , ( [ [ n ( term ) , * ( , ( [ [ t ( or ) , n ( term ) ] ) ) ] ) ] )\n vs.\n - [] , ( [ [ ? ( n ( add_op ) ) , n ( term ) , * ( , ( [ [ t ( or ) , n ( term ) ] ) ) ] ) ] )\n - Ok: term.\n- Fail (1/1): factor.\n - [] , ( [ [ * ( ; ( [ t ( - ) , t ( + ) ] ) ) , n ( primary ) , ? ( , ( [ [ t ( ' ) , t ( . ' ) ] ) ) , n ( primary ) ) ] ) ] )\n vs.\n - [] , ( [ [ n ( primary ) , ? ( , ( [ [ t ( ' ) , t ( . ' ) ] ) ) , n ( primary ) ) ] ) ] )\n - Fail (1/1): output_expression_list.\n - [] , ( [ [ , ( [ t ( UNSIGNED_NUMBER ) , t ( true ) , t ( false ) , t ( STRING ) , n ( component_reference ) , t ( der ) , t ( ( ) , n ( output_expression_list ) , t ( ) ) ) , , ( [ t ( ( ) , n ( function_call_args ) , t ( ) ) ] ) , , ( [ t ( ( ) , n ( function_arguments ) , t ( ) ) ] ) , , ( [ t ( ) , n ( function_arguments ) , t ( ) ) ] ) , t ( end ) ] ) ] )\n vs.\n - [] , ( [ [ , ( [ t ( UNSIGNED_NUMBER ) , t ( STRING ) , t ( true ) , t ( false ) , , ( [ ; ( [ n ( name ) , t ( der ) , t ( initial ) ] ) , n ( component_reference ) , t ( der ) , t ( ( ) , n ( output_expression_list ) , t ( ) ) ) , , ( [ t ( ) , n ( function_call_args ) , t ( ) ) ] ) , , ( [ t ( ) , n ( function_arguments ) , t ( ) ) ] ) , t ( end ) ] ) ] )\n - Fail (1/1): function_call_args.\n - Ok: function_call_args.\n - Fail (1/1): named_arguments.\n - [] , ( [ [ , ( [ t ( function ) , n ( name ) , t ( ) , ? ( n ( function_arguments ) ) ] ) ] ) ] )\n vs.\n - [] , ( [ [ , ( [ t ( function ) , n ( name ) , t ( ) , ? ( n ( named_arguments ) ) ] ) , n ( expression ) ] ) ] )\n - Ok: named_arguments.\n - Ok: expression_list.\n - Ok: comment.\n- Fail (1/1): component_reference.\n - [] , ( [ [ , ( [ t ( IDENT ) , ? ( n ( array_subscripts ) ) , * ( , ( [ t ( ) , t ( IDENT ) , ? ( n ( array_subscripts ) ) ] ) ) ] ) , , ( [ t ( ) , t ( IDENT ) , * ( , ( [ t ( ) , t ( IDENT ) , ? ( n ( array_subscripts ) ) ] ) ) ] ) ) ] )\n vs.\n - [] , ( [ [ , ( [ t ( ) , t ( IDENT ) , ? ( n ( array_subscripts ) ) , * ( , ( [ t ( ) , t ( IDENT ) , ? ( n ( array_subscripts ) ) ] ) ) ] ) ] )\n - Fail (1/1): name.\n - [] , ( [ [ , ( [ t ( IDENT ) , ? ( n ( array_subscripts ) ) , * ( , ( [ t ( ) , t ( IDENT ) , ? ( n ( array_subscripts ) ) ] ) ) ] ) ] )\n - Fail (1/1): identifier.\nAPPENDIX D. COMPARATOR OUTPUT\n\nListing D.2: Final Comparator Output of the Modelica Specification vs. JModelica\n\nD.2 Modelica Specification vs. OpenModelica\n\n```\nD.2 Modelica Specification vs. OpenModelica\n\nvm@vm-VirtualBox:~/Dokumente/impl/lfcS ././slps-master/shared/tools/gdt bgf/expr\n-o.bgf bgf/expr-m.bgf\nNormalizing bgf/expr-o.bgf.\nNormalizing bgf/expr-m.bgf.\nDiffer bgf/expr-o.bgf and bgf/expr-m.bgf.\n\n- Names of defined nonterminals differ.\n - Intersection [expression, simple_expression, logical_expression, logical_term, logical_factor, relation, arithmetic_expression, term, factor, primary, component_reference, function_arguments, named_arguments, named_argument, output_expression_list, expression_list, array_subscripts, subscript, comment, string_comment, annotation].\n - bgf/expr-o.bgf only: [part_eval_function_expression, if_expression, else_expression_list, elseif_expression, simple_expr, unary_arithmetic_expression, matrix_expression_list, component_reference, function_call, component_reference2, function_call, for_or_expression_list, for_or_expression_list2, subscript_list].\n - bgf/expr-m.bgf only: [rel_op, add_op, mul_op, name, function_call, args, function_argument].\n\nComparisons per (common) nonterminal:\n\n- Fail (1/1): expression.\n - []:([n(if_expression),n(simple_expression),n(code_expression),n(part_eval_function_expression),n(match_expression)])\n vs.\n - []:([n(simple_expression),n([t(if),n(expression),t(then),n(expression)])\n *([t(else),n(expression),t(then),n(expression)])],t(else),n(expression)])]\n\n- Fail (1/1): simple_expression.\n - []:([n(simple_expr),?([t(COLONCOLON),n(simple_expression)])])\n vs.\n - []:([n(simple_expr),?([t(:),n(logical_expression),?([t(:),n(logical_expression),]))])]\n\n- Fail (1/1): logical_expression.\n - []:([n(logical_term),*(t(T,OR)n(logical_term))])\n vs.\n - []:([n(logical_term),*(t(T,OR)n(logical_term))])\n\n- Fail (1/1): logical_term.\n - []:([n(logical_factor),*(t(T,AND)n(logical_factor))])\n vs.\n - []:([n(logical_factor),*(t(T,AND)n(logical_factor))])\n\n- Fail (1/1): logical_factor.\n - []:([t(T,NOT)n(match)])\n vs.\n - []:([t(T,NOT)n(match)])\n```\n\n\nD.2. MODELICA SPECIFICATION VS. OPENMODELICA\n\n101\n\n30 - Fail (1/1): relation.\n - [ ] , [(n[arithmetic_expression]), ?(, ([t(LESS), t(LESSEQ), t(GREATER), t(GREATERT)]]), n[arithmetic_expression]]]\n vs.\n - [ ] , [(n[arithmetic_expression]), ?(, ([n(rel_op), n[arithmetic_expression]])]\n\n35 - Fail (1/1): arithmetic_expression.\n - [ ] , [(n[unary_arithmetic_expression]), *(, ([t(PLUS), t(MINUS), t(PLUS_EW), t(MINUS_EW)])]\n vs.\n - [ ] , [(?n(add_op)), n(term)], *(, ([n(add_op), n(term)])]\n\n40 - Fail (1/1): term.\n - [ ] , [(n(factor)), *(, ([t(STAR), t(SLASH), t(STAR_EW), t(SLASH_EW)])]\n vs.\n - [ ] , [(n(factor)), *(, ([n(mul_op), n(factor)])]\n\n45 - Fail (1/1): factor.\n - [ ] , [(n(primary)), ?(, ([t(POWER), t(POWER_EW)])]\n vs.\n - [ ] , [(n(primary)), ?(, ([t(\\`), t(\\`)])]\n\n50 - Fail (1/1): primary.\n - [ ] , [(t(UNSIGNED_INTEGER), t(UNSIGNED_REAL), t(STRING), t(TFALSE), t(TTRUE), n(component_reference.function_call), [t(ID), n(function_call)])]\n vs.\n - [ ] , [(t(UNSIGNED_NUMBER), t(STRING), t(TRUE), t(FALSE), t(INITIAL)], n(function_call_args), n(component_reference), [t(\\{), n(output_expression_list), t(\\})]], t(f\nt(component_reference_list), t(\\}))], t(function_arguments, t(\\}))], t(end))\n\n55 - Fail (1/1): component_reference.\n - [ ] , [(?t(DOT), n(component_reference2)], t(ALLWILD), t(WILD)])\n vs.\n - [ ] , [(t(\\), t(IDENT)), n(array_subscripts)], *(, ([t(\\), t(IDENT)], n(array_subscripts))]\n\n60 - Fail (1/1): function_arguments.\n - [ ] , [(n(function_argument)], ?(, ([n(\\), n(function_arguments)])]\n vs.\n - [ ] , [(n(function_argument)], ?(, ([t(COMMA), n(function_arguments)])]\n\n65 - Fail (1/1): named_arguments.\n - [ ] , [(n(named_argument)], ?(, ([t(COMMA), n(named_arguments)])]\n vs.\n - [ ] , [(t(IDENT), t(=)], n(function_argument)]\n\n70 - Fail (1/1): output_expression_list.\n - [ ] , [(t(RPAR), [t(COMMA), n(output_expression_list)], n(output_expression_list), t(RPAR)])]\n vs.\n - [ ] , [(n(output_expression)], *(, ([t(\\), ?(n(output_expression)])]\n\n75 - Fail (1/1): expression_list.\n - [ ] , [(n(expression)], ?(, ([t(COMMA), n(expression_list)])]\n vs.\n - [ ] , [(n(expression)], *(, ([t(\\), n(subscript_list)])]\n\n80 - Fail (1/1): array_subscripts.\n - [ ] , [(t(LBRACK), n(subscript_list), t(RBRACK)])\n vs.\n - [ ] , [(t(\\)), n(subscript)], *(, ([t(\\)), n(subscript)])]\nAPPENDIX D. COMPARATOR OUTPUT\n\nListing D.3: Initial Comparator Output of the Modelica Specification vs. OpenModelica\n\n```\nFail (1/1): subscript.\n- [] ;( [n(expression), t(COLON)])\nvs.\n- [] ;( [t(:), n(expression)])\n- Ok: comment.\n\nFail (1/1): string_comment.\n- [] ;( [t(STRING), *( [t(PLUS), t(STRING)] )])\nvs.\n- [] ;( [t(STRING), *( [t(+), t(STRING)] )])\n\nFail (1/1): annotation.\n- [] ;( [t(ANNOTATION), n(class_modification)])\nvs.\n- [] ;( [t(ANNOTATION), n(class_modification)])\n- Roots agree.\n\nDiffing bgf/expr-o.rename.sub.exp.rel.mul.una.ifexp.output.matrix.ref.for.fct.call.part.smp.eliminate.bgf\n- Names of defined nonterminals differ.\n- Intersection [expression, simple_expression, logical_expression, logical_term, logical_factor, relation, arithmetic_expression, term, factor, primary, component_reference, function_call_args, named_arguments, named_argument, expression_list, array_subscripts, subscript, comment, string_comment, annotation, rel_op, mul_op, add_op, output_expression_list, function_arguments, name, function_argument].\n- bgf/expr-o.rename.sub.exp.rel.mul.una.ifexp.output.matrix.ref.for.fct.call.part.smp.eliminate.bgf only: [part_eval_function_expression, for_or_expression_list].\n- bgf/expr-m.bgf only: [ ].\n- Comparisons per (common) nonterminal:\n - Fail (1/1): expression.\n - [] ;( [t(if), n(expression), t(then), n(expression)], *( [t(else_if), n(expression), t(then), n(expression)]), t(else), n(expression)])\n vs.\n - [] ;( [n(simple_expression), *( [t(if), n(expression), t(then), n(expression)], *( [t(else_if), n(expression), t(then), n(expression)]))], t(else), n(expression)])\n - Ok: simple_expression.\n - Ok: logical_expression.\n - Ok: logical_term.\n - Ok: logical_factor.\n - Ok: relation.\n - Ok: arithmetic_expression.\n - Ok: factor.\n - Fail (1/1): primary.\n - [] ;( [ [n(name), t(der)]], n(function_call_args)], t(UNSIGNED_NUMBER), t(STRING), t(false), t(true), n(component_reference), [t(initial), t(), t()])\n vs.\n```\nD.3. OPENMODELICA VS. JMODELICA\n\nListing D.4: Final Comparator Output of the Modelica Specification vs. OpenModelica\n\nD.3 OpenModelica vs. JModelica\n\n- Names of defined nonterminals differ.\n - Intersection: array_subscripts, subscript, annotation, expression, simple_expression, logical_expression, relation, arithmetic_expression, term, factor, primary, output_expression_list, function_call_args, function_arguments, named_arguments, function_argument, named_argument, expression_list, comment,\nD.3. OPENMODELICA VS. JMODELICA\n\nListing D.5: Initial Comparator Output of OpenModelica vs. JModelica\n\n```\nvm@vm-VirtualBox:~/Dokumente/impl/lcf$ ../../slps-master/shared/tools/gdt bgf/tgt-j.tgt.bgf bgf/tgt-o.elim.bgf\nNormalizing bgf/tgt-j.tgt.bgf.\nNormalizing bgf/tgt-o.elim.bgf.\nDiffering bgf/tgt-j.tgt.bgf and bgf/tgt-o.elim.bgf.\n5 - Names defined nonterminals differ.\n - Intersection [array_subscripts, subscript, annotation, expression, simple_expression, logical_expression, relation, arithmetic_expression, term, factor, primary_output_expression_list, function_call_args, function_arguments, named_arguments, function_argument, named_argument, expression_list, comment, component_reference, rel_op, add_op, mul_op, string_comment, logical_factor, part_eval_function_expression, for_or_expression_list].\n - bgf/tgt-j.tgt.bgf only: [].\n - bgf/tgt-o.elim.bgf only: [logical_term].\n5 - Comparisons per (common) nonterminal:\n - Ok: array_subscripts.\n - Ok: subscript.\n - Ok: annotation.\n - Fail (1/1): expression.\n - vs.\n - Ok: simple_expression.\n```\n\nAppendix D. Comparator Output\n\n- Fail (1/1): logical_expression.\n - [ ] , ( [ n ( logical_factor ) , * ( , ( [ t ( or ) , t ( and ) ] ) , n ( logical_expression ) ) ] )\n vs.\n - [ ] , ( [ n ( logical_term ) , * ( , ( [ t ( or ) , n ( logical_term ) ] ) ) ] )\n Ok: relation.\n\n- Fail (1/1): arithmetic_expression.\n - [ ] , ( [ n ( term ) , * ( , ( [ n ( add_op ) , n ( term ) ] ) ) ] )\n vs.\n - [ ] , ( [ n ( logical_factor ) , * ( , ( [ n ( add_op ) , n ( term ) ] ) ) ] )\n Ok: term.\n\n- Fail (1/1): factor.\n - [ ] , ( [ n ( expression ) , ? ( , ( [ t (ˆ) , t ( . ˆ ) ] ) ) ) ]\n vs.\n - [ ] , ( [ n ( primary ) , ? ( , ( [ t (ˆ) , t ( . ˆ ) ] ) ) ) ]\n Fail (1/1): primary.\n\n- Fail (1/1): function_arguments.\n - [ ] ; ( [ n ( expression ) , t ( for ) , n ( for_indices ) ] )\n vs.\n - [ ] ; ( [ n ( expression ) , t ( for ) , n ( for_indices ) ] )\n Ok: function_arguments.\n\n- Fail (1/1): named_argument.\n - [ ] , ( [ t ( IDENT ) , t ( = ) , n ( function_argument ) ] )\n vs.\n - [ ] , ( [ t ( IDENT ) , t ( = ) , n ( function_argument ) ] )\n Ok: named_argument.\n\n- Fail (1/1): logical_factor.\n - [ ] , ( [ n ( logical_factor ) , * ( , ( [ t ( or ) , t ( and ) ] ) , n ( logical_expression ) ) ] )\n vs.\n - [ ] , ( [ n ( logical_term ) , * ( , ( [ t ( or ) , n ( logical_term ) ] ) ) ] )\n Fail (1/1): logical_expression.\n\n- Fail (1/1): arithmetic_expression.\n - [ ] , ( [ n ( term ) , * ( , ( [ n ( add_op ) , n ( term ) ] ) ) ] )\n vs.\n - [ ] , ( [ n ( logical_factor ) , * ( , ( [ n ( add_op ) , n ( term ) ] ) ) ] )\n Fail (1/1): logical_expression.\nD.3. OPENMODELICA VS. JMODELICA\n\n− Ok: `part_eval_function_expression`.\n− Fail (1/1): `for_or_expression_list`.\n − `[[], ([n(function_argument), t(for), n(for_indices)])], ([n(function_argument), *([t(., n(function_argument))]), t(., n(named_arguments))]), n(named_arguments)]`\n vs.\n − `[[], ?(n(function_argument), ?([t(., n(function_argument))]), t(., n(named_arguments)))]`\n − Roots agree.\n\nListing D.6: Final Comparator Output of OpenModelica vs. JModelica\nAppendix E\n\nGrammar Transformations\n\nThe grammar transformations in this chapter are given in the order they are applied. All transformations independent of whether they lead to convergence of the productions targeted are included. They are pretty-printed versions of the original XML files. Each block is one XBGF file as specified within the corresponding LCF. Apart from the renamings, one XBGF file caters one fail note or one unit of productions modeling a certain construct within the grammar.\n\nE.1 Modelica Specification vs. JModelica\n\nThe renamings in this XBGF file dissolve three nominal mismatches, which arise because JModelica uses shorter nonterminal symbols. They are abbreviated versions of the Modelica specification symbols.\n\n```\nrenameN(exp, expression);\nrenameN(log_exp, logical_expression);\nrenameN(aritm_exp, arithmetic_expression);\n```\n\nListing E.1: Renaming of Nonterminals\n\nThe transformations in this XBGF file rename terminals. JModelica uses uppercase letters to denote terminals. Operators and parentheses are not specified by the symbol but by the name of the symbol written out. The terminals are transformed into the specification versions. The flex definition of JModelica confirms the translation of the terminals into lexical units that coincide with the Modelica specification.\n\n```\nrenameT(\"LBRACK\", \"[\");\nrenameT(\"RBRACK\", \"]\");\nrenameT(\"LPAREN\", \"(\");\nrenameT(\"RPAREN\", \")\");\nrenameT(\"LBRACE\", \"{\");\nrenameT(\"RBRACE\", \"}\");\nrenameT(\"COLON\", \":\");\nrenameT(\"COMMA\", \",\");\nrenameT(\"EQUALS\", \";\");\nrenameT(\"ANNOTATION\", \"annotation\");\nrenameT(\"IF\", \"if\");\nrenameT(\"THEN\", \"then\");\nrenameT(\"ELSEIF\", \"elseif\");\nrenameT(\"ELSE\", \"else\");\nrenameT(\"OR\", \"or\");\n```\nAPPENDIX E. GRAMMAR TRANSFORMATIONS\n\nrenameT(\"AND\", \"and\");\nrenameT(\"NOT\", \"not\");\nrenameT(\"TRUE\", \"true\");\nrenameT(\"FALSE\", \"false\");\nrenameT(\"FOR\", \"for\");\nrenameT(\"END\", \"end\");\n\nListing E.2: Renaming of Terminals\n\nThe transformations alter the JModelica productions subscript_list and subscript to converge with the Modelica specification. The transformations alter the productions in the following way:\n\n```plaintext\nsubscript_list : subscript | subscript_list \",\" subscript\n```\n\n```plaintext\narray_subscripts : [\"\" subscript_list \"]\n```\n\n```plaintext\nvertical(in subscript_list);\ndeyaccify(subscript_list);\ninline(subscript_list);\n```\n\nListing E.3: Refactoring of Subscripts\n\nThe XBGF transformations for the if expressions alter the production elseif_exp in a similar way as described for subscripts. Inlining completes the convergence.\n\n```plaintext\nvertical(in elseif_exp);\ndeyaccify(elseif_exp);\ninline(elseif_exp);\ninline(if_exp);\n```\n\nListing E.4: Refactoring of If Expressions\n\nTo align the simple expressions, we perform the same two transformations twice. First, we factor out a logical expression and massage the epsilon choice into an optional. Second, we factor out a colon and a logical expression and massage the epsilon choice again. The states of the definition of the nonterminal simple_expression are, with l_e standing for logical_expression:\n\n```plaintext\nl_e | l_e \":\" l_e | l_e \":\" l_e \":\" l_e\n```\n\n```plaintext\nfactor((logical_expression | (logical_expression \":\" logical_expression) | (logical_expression \":\" logical_expression \":\" logical_expression)),\nlogical_expression (EPSILON | (\":\" logical_expression) | (\":\" logical_expression \":\" logical_expression)));\nmassage((EPSILON | (\":\" logical_expression) | (\":\" logical_expression \":\" logical_expression) | (\":\" logical_expression \":\" logical_expression) | (\":\" logical_expression \":\" logical_expression)),\nfactor(((\":\" logical_expression) | (\":\" logical_expression \":\" logical_expression) | (\":\" logical_expression \":\" logical_expression) | (\":\" logical_expression \":\" logical_expression) | (\":\" logical_expression \":\" logical_expression)),\nmassage((EPSILON | (\":\" logical_expression)),\n```\nE.1. MODELICA SPECIFICATION VS. JMODELICA\n\nNext, we consider the relations. With the different relational operators between two arithmetic expressions in an own choice, we need to factor out the front and end arithmetic expression and extract the operators. Then, we move on to align the rest of the production arithmetic_expression by factoring and massaging in the same way as we have done before with the simple expressions.\n\n```plaintext\nfactor( \n (arithmetic_expression \"LT\" arithmetic_expression) | (arithmetic_expression \"LEQ\" arithmetic_expression) | (arithmetic_expression \"GEQ\" arithmetic_expression) | (arithmetic_expression \"EQ\" arithmetic_expression) | (arithmetic_expression \"GT\" arithmetic_expression) | (arithmetic_expression \"NEQ\" arithmetic_expression) | arithmetic_expression) , \n (arithmetic_expression) ;\n\nrenameT(\"LT\", \"<\");\nrenameT(\"LEQ\", \"\\leq\");\nrenameT(\"GEQ\", \"\\geq\");\nrenameT(\"EQ\", \"=\");\nrenameT(\"GT\", \">\");\nrenameT(\"NEQ\", \"\\neq\");\nextract( rel_op : \"<\" | \"\\leq\" | \"\\geq\" | \"=\" | \"\\neq\" | \">\");\n\nfactor( \n (arithmetic_expression rel_op arithmetic_expression) | arithmetic_expression) , \n arithmetic_expression (EPSILON));\n\nmassage( \n (rel_op arithmetic_expression) | EPSILON), \n (rel_op arithmetic_expression) ?);\n```\n\nThe transformations in this block concern the arithmetic operators which we need to extract, as well. To be able to do that, we need to factor out the terms in front and behind the operators and extract them.\n\n```plaintext\nfactor( \n (multiplicative_exp | (additive_exp \"PLUS\" multiplicative_exp) | (additive_exp \"MINUS\" multiplicative_exp) | (additive_exp \"DOTPLUS\" multiplicative_exp) | (additive_exp \"DOTMINUS\" multiplicative_exp)) , \n (multiplicative_exp | (additive_exp ((\"PLUS\" multiplicative_exp) | (\"MINUS\" multiplicative_exp) | (\"DOTPLUS\" multiplicative_exp) | (\"DOTMINUS\" multiplicative_exp)))));\n\nfactor( \n (multiplicative_exp | (additive_exp ((\"PLUS\" multiplicative_exp) | (\"MINUS\" multiplicative_exp) | (\"DOTPLUS\" multiplicative_exp) | (\"DOTMINUS\" multiplicative_exp))));\n```\nAPPENDIX E. GRAMMAR TRANSFORMATIONS\n\nListing E.7: Refactoring of Arithmetic Operators\n\nThe terminals that denote a power symbol need not be extracted. They have to be in the same form of a choice but not in an own production, rather as an inner choice. Thus, we factor out the start and end terms but do not extract the inner choice. We finish the transformation chain with massaging the epsilon choice and renaming the terminals and the production head. The steps in the transformation are the following; \\( p \\) stands for primary and the power symbols are already renamed for this description:\n\n\\[\n\nd + n | - n | .+ | .- \\\\\n\n\\]\n\nListing E.8: Refactoring of Power Expressions\n\nThe arithmetic expression is solely defined by an additive expression that is not part of the Modelica specification. Thus, we inline the deyaccified additive expression. The multiplicative\nexpression is also deyaccified and in addition, renamed. At this point, JModelica includes a unary expression that holds the sign symbols. It means that the production `term` fails while the production `factor` agrees and we have an exclusive production for JModelica. Later, we will dissolve the exclusive production which moves the signs into the production `factor`. The result is that we have one exclusive production less, the terms agree, and the factors fail.\n\n```plaintext\nvertical( in additive_exp );\ndeyaccify( additive_exp );\ninline( additive_exp );\nvertical( in multiplicative_exp );\ndeyaccify( multiplicative_exp );\nrenameN( multiplicative_exp, term );\n```\n\nListing E.9: Refactoring of Arithmetic Expressions\n\nThe states the comments pass through during transformation are:\n\n```plaintext\nstring_comment: \"STRING\" | string_comment \"+\" \"STRING\"\n=> string_comment: \"STRING\" ( \"+\" \"STRING\" )\ncomment: string_comment ? annotation ?\n=> comment: ( \"STRING\" ( \"+\" \"STRING\" )* )? annotation ?\nstring_comment: ( \"STRING\" ( \"+\" \"STRING\" )* )?\n```\n\nListing E.10: Refactoring of Comments\n\nWe introduce a new nonterminal, logical factors, by extracting the respective part of the logical expressions. The commonly used combination of factoring and massaging completes the convergence.\n\n```plaintext\nextract( logical_factor:\n \"not\" relation | relation\n);\nfactor( (\"not\" relation) | relation ),\n(\"not\" | EPSILON) relation);\nmassage( (\"not\" | EPSILON),\n\"not\" ?);\n```\n\nListing E.11: Refactoring of Logical Factors\n\nThe matrices in JModelica model one choice in the primaries and the expression lists in the Modelica specification. The transformation `deyaccify` resolves the differences together with renamings and inlining.\n\n```plaintext\nvertical( in matrix_row );\ndeyaccify( matrix_row );\nrenameN( matrix_row, expression_list );\nvertical( in matrix );\ndeyaccify( matrix );\n```\nListing E.12: Refactoring of Matrices\n\nThe following transformations deal with aligning the component references. The first three transformations do the following:\n\n```\nparsesAccessLoc = parsesAccessSingle | parsesAccessSingle DOT\n```\n\nThe inline transformations eliminate nominal mismatches, the renamings align nonterminal and terminal symbols. The first line of the following listing depicts the definition of `parsesAccess` after distribution. The other lines show the result of the transformations, excluding the last unfolding.\n\n```\nparsesAccess : \"IDENT\" array_subscripts? ( DOT parsesAccess array_subscripts? ) |\n| DOT \"IDENT\" |\n| DOT \"IDENT\" DOT array_subscripts? DOT \"IDENT\" DOT array_subscripts? |\n\n⇒ parsesAccess : \"IDENT\" array_subscripts? ( DOT parsesAccess array_subscripts? ) |\n| DOT \"IDENT\" DOT ( DOT parsesAccess array_subscripts? DOT \"IDENT\" DOT array_subscripts? ) |\n\n⇒ parsesAccess : \"IDENT\" array_subscripts? ( helper ) |\n| DOT \"IDENT\" DOT ( DOT parsesAccess array_subscripts? ) |\n\n⇒ parsesAccess : \"IDENT\" array_subscripts? ( helper ) |\n| DOT \"IDENT\" DOT ( DOT parsesAccess array_subscripts? ) |\n\n⇒ parsesAccess : \"IDENT\" array_subscripts? ( helper ) |\n| DOT \"IDENT\" DOT ( DOT ParsesAccess array_subscripts? ) |\n\n⇒ parsesAccess : \"IDENT\" array_subscripts? ( helper ) |\n| DOT \"IDENT\" DOT ( DOT parsesAccess array_subscripts? ) |\n```\n\nThe last transformation unfolds this definition into the definition of component references, which has been defined solely by the nonterminal `parsesAccess`. The parse access expression becomes the names expression later on.\n\n```\nvertical ( in parsesAccessLoc );\ndeyaccify ( parsesAccessLoc );\nmassage ( |\n| parsesAccessSingle DOT parsesAccessSingle , |\n| parsesAccessSingle DOT parsesAccessSingle* ) ; |\n| parsesAccessSingle DOT parsesAccessSingle ; |\n| parsesAccessSingle DOT parsesAccessSingle ; |\n| inlinex ( parsesAccessSingle ) ; |\n| inlinex ( firstClassAccess ) ; |\n| renameN ( accessExpression , componentReference ) ; |\n| renameT ( \"DOT\" , \")\" ) ; |\n| distribute ( in parsesAccess ) ; |\n| factor ( |\n| \"IDENT\" array_subscripts? DOT ( DOT \"IDENT\" array_subscripts? ) DOT ( DOT \"IDENT\" array_subscripts? ) |\n| ( DOT \"IDENT\" DOT array_subscripts? DOT \"IDENT\" DOT array_subscripts? ) ) |\n| ( DOT \"IDENT\" DOT array_subscripts? DOT ( DOT EPSILON DOT \"IDENT\" DOT array_subscripts? ) ) |\n| ( DOT \"IDENT\" DOT array_subscripts? DOT ( DOT \"IDENT\" DOT array_subscripts? ) ) ) ) ; |\n| massage ( |\nThe states the production named_arguments passes through are:\n\n\\[\n\\begin{align*}\n\\text{named_arguments} & : \\text{named_argument} | \\text{named_arguments} \",\" \\text{named_argument} \\\\\n\\Rightarrow & \\quad \\text{named_arguments} : \\text{named_argument} (\",\" \\text{named_argument}) \\\\\n\\Rightarrow & \\quad \\text{named_arguments} : \\text{named_argument} (\"\",\")* \\text{named_argument} \\\\\n\\Rightarrow & \\quad \\text{named_arguments} : \\text{named_argument} | \\text{named_argument} \",\" \\text{named_arguments} \\\\\n\\Rightarrow & \\quad \\text{named_arguments} : \\text{named_argument} (< | \",\" \\text{named_arguments}) \\\\\n\\end{align*}\n\\]\n\nThe last two transformations align the production named_argument.\n\nWe deal with partial function calls. We inline the corresponding production to eliminate the exclusive nonterminal and align the production function_argument. The nonterminal parse_access becomes name, the terminal \"FUNCTION\" becomes \"function\".\n\n\\[\n\\begin{align*}\n\\text{inl ine} (\\text{partial_function_call})\n\\Rightarrow & \\quad \\text{renameT} (\"FUNCTION\", \"function\") \\\\\n\\Rightarrow & \\quad \\text{renameN} (\\text{parse_access}, \\text{name}) \\\\\n\\end{align*}\n\\]\nWe introduce the formerly exclusive Modelica specification nonterminal function_call_args by extracting the definition out of the production function_call. Then, we inline the function calls to eliminate the exclusive OpenModelica nonterminal function_call and to align the structure of the primary definition. The next transformations aligns the production function_arguments. The last two transformations inline the “der” expressions into the primaries and rename a terminal.\n\nextract(\n function_call_args:\n \"(\" function_arguments? \")\"\nin function_call);\ninline(function_call);\nvertical(in arg_list_p);\ndeyaccify(arg_list_p);\ninline(dér_expression);\nrenameT(\"DER\" , \"der\");\n\nListing E.16: Refactoring of Function Calls and Function Arguments\n\nThe transformations eliminate two choices of the production primary.\n\nvertical(in primary);\nremoveV(\n primary:\n \"UNSIGNEDINTEGER\"\n);\nremoveV(\n primary:\n \"TIME\"\n);\nhorizontal(in primary);\n\nListing E.17: Elimination of Redundant Choices\n\nThe final refactorings transform the logical expressions, eliminate the unary expressions, and introduce output expression lists. The first block alters the definition of logical expressions, abbreviated by l_e, logical factors are abbreviated by l_f:\n\n\\[\n\\begin{align*}\n\\text{l_e} & \\text{ or } \\text{l_e} \\mid \\text{l_e} \\text{ and } \\text{l_e} \\mid \\text{l_f} \\\\\n\\Rightarrow & \\text{l_e} ( \\text{ or } \\text{l_e} \\mid \\text{l_e} \\text{ and } \\text{l_e} ) \\mid \\text{l_f} \\\\\n\\Rightarrow & \\text{l_e} ( \\text{ or } \\text{l_e} \\text{ and } ) \\mid \\text{l_e} \\mid \\text{l_f} \\\\\n\\Rightarrow & \\text{l_f} ( ( \\text{ or } \\text{l_e} \\text{ and } ) \\mid \\text{l_e} ) \\\\\n\\end{align*}\n\\]\n\nThe unary expressions change through the course of transformation in the following way:\n\n\\[\n\\begin{align*}\n\\text{unary_exp} & : \\text{factor} \\mid \\text{\"-\" unary_exp} \\mid \\text{\"+\" unary_exp} \\\\\n\\Rightarrow & \\text{unary_exp} : \\text{factor} \\mid ( \\text{\"-\"} \\text{\"+\"} ) \\text{ unary_exp} \\\\\n\\Rightarrow & \\text{unary_exp} : ( \\text{\"-\" \\\"+\"} ) \\text{ primary } ( ( \\text{\"-\" \\\"+\"} ) \\text{ primary } )? \\\\\n\\Rightarrow & \\text{factor} : ( \\text{\"-\" \\\"+\"} ) \\text{ primary } ( ( \\text{\"-\" \\\"+\"} ) \\text{ primary } )?\n\\end{align*}\n\\]\n\nTo extract the output expression list which is in JModelica a single expression, we have to temporarily extract the “der” expression to be able to extract only the intended expression in the definition of the primaries. The last three transformations handle the introduction of output expression lists.\nE.2 Modelica Specification vs. OpenModelica\n\nDue to the higher alignment in structure, OpenModelica and the Modelica specification share more nonterminals than the specification and JModelica. Renamings of nonterminals occur later in the process when working through the fail notes but not in the beginning like in the LCI of the Modelica specification and JModelica. The process starts with renamings of terminals.\n\n```plaintext\n- renameT(\"T_OR\",\"or\");\n- renameT(\"T_AND\",\"and\");\n- renameT(\"T_NOT\",\"not\");\n- renameT(\"LESS\",\"<\");\n- renameT(\"LESSEQ\",\"<=\");\n- renameT(\"GREATER\">\");\n- renameT(\"GREATEREQ\",\">=\");\n- renameT(\"EQEQ\",\"==\");\n- renameT(\"LESSGT\",\"<>\" AUTHOR: E.2d Modelica Specification vs. OpenModelica\n\nListing E.18: Final Refactorings for Clarification of Differences\n\nlogical_expression (\"or\" logical_expression) | (\"and\" logical_expression));\nfactor( ((\"or\" logical_expression) | (\"and\" logical_expression)),\n (\"or\" | \"and\") logical_expression);\nextract( op:\n \"or\" | \"and\"\n);\nvertical( in logical_expression );\ndeacify(logical_expression);\ninline (op);\nfactor( ((\"-\" unary_exp) | (\"+\" unary_exp)),\n (\"-\" | \"+\") unary_exp);\nextract( op:\n \"+\" | \"+\"\n);\nvertical( in unary_exp );\ndeacify(unary_exp);\ninline (op);\ninline (factor);\nrenameN(unary_exp, factor);\nextract( der_prod:\n \"der\" \"(\" expression \")\"\n);\nextract( output_expression_list:\n expression\n in primary);\ninline (der_prod);\n```\nAppendix E. Grammar Transformations\n\nrenameT (\"POWER\", \"^\" );\nrenameT (\"POWERW\", \"\\^\" );\nrenameT (\"T.FALSE\", \"false\" );\nrenameT (\"T.TRUE\", \"true\" );\nrenameT (\"DER\", \"der\" );\nrenameT (\"LPAR\", \"(\" );\nrenameT (\"RPAR\", \")\" );\nrenameT (\"LBRACK\", \"[ \"\");\nrenameT (\"RBRACK\", \"] \"\");\nrenameT (\"LBRACE\", \"{ \"\");\nrenameT (\"RBRACE\", \"} \"\");\nrenameT (\"T.END\", \"end\" );\nrenameT (\"DOT\", \". \"\");\nrenameT (\"COMMA\", \",\" );\nrenameT (\"EQUALS\", \":=\" );\nrenameT (\"COLON\", \"::\" );\nrenameT (\"FUNCTION\", \"function\" );\nrenameT (\"OPERATOR\", \"operator\" );\nrenameT (\"AS\", \"as\" );\nrenameT (\"COLUMN\", \"::\" );\n\nListing E.19: Renaming of Terminals\n\nThe subscript lists need to be inlined. Before doing so, we need to transform the definition into the form subscript (\" \", subscript )\\* . The steps towards convergence lead to the following interim definitions of subscript lists:\n\n```\nsubscript (\" \", subscript_list )?\n => subscript ( \\epsilon | \" \", subscript_list )\n => subscript | subscript \" \", subscript_list\n => ( subscript \" \", )* subscript\n => subscript (\" \", subscript )*\n```\n\n```\nmassage(\n (\" \", subscript_list )?,\n {(\" \", subscript_list ) | EPSILON});\nvertical( in subscript_list );\ndeyaccify ( subscript_list );\nmassage(\n (subscript \" \")* subscript,\n subscript (\" \", subscript )*)\ninline ( subscript_list );\n```\n\nListing E.20: Refactoring of Subscripts\n\nExpression lists are transformed in the same way as are subscript lists, leading to the following transformation process:\n\n```\nexpression (\" \", expression_list )?\n => expression ( \\epsilon | \" \", expression_list )\n => expression | expression \" \", expression_list\n => ( expression \" \", )* expression\n => expression (\" \", expression )*\n```\n\n```\nmassage(\n (\" \", expression_list )?,\n {(\" \", expression_list ) | EPSILON});\ndistribute( in expression_list );\nvertical( in expression_list );\n```\nE.2. MODELICA SPECIFICATION VS. OPENMODELICA\n\ndeyaccify(expression_list);\nmassage((expression \"\",\"\" expression,\nexpression (\"\",\"\" expression)*));\n\nListing E.21: Refactoring of Expression Lists\n\nThe relational, additive, and multiplicative operators already are in an inner choice that can be extracted. The next two transformation listings do exactly that for relational and multiplicative operators.\n\nextract(\n rel_op: \"<\" | \"<=\" | \"=\" | \">=\" | \">=\" | \"<>\"\n);\n\nListing E.22: Refactoring of Relational Operators\n\nextract(\n mul_op: \"*\" | \"/\" | \".*\" | \"./\"\n);\n\nListing E.23: Refactoring of Multiplicative Operators\n\nFor the additive operators, we first need to bring the additive operators in the definition of unary expressions into the form of an inner choice. The extraction of the operators replaces every occurrence of them. This way, they already appear in the extractable form in the unary expression when extracted and we do not have to fold the definition of the operators into the production afterwards. The refactoring of the inner choice of additive operators in the unary expressions generates an epsilon alternative which is massaged in the end into an optional. The inlining of the unary expressions aligns the arithmetic expressions and eliminates the exclusive OpenModelica nonterminal unary_arithmetic_expression.\n\nfactor(\n ((\"+\" term) | (\"-\" term) | (\".+\" term) | (\".-\" term) | term),\n (\"+\" | \"-\" | \".+\" | \".-\" | EPSILON) term);\n\nListing E.24: Refactoring of Unary Expressions\n\nIf expressions need a few inlinings, renamings and a refactoring of the “elseif ” part. Elseif expression lists are transformed in the same way as subscript and expression lists, except that the last step includes a different massaging operation.\n\nelseif_expression_list : elseif_expression elseif_expression_list?\n=> elseif_expression_list : elseif_expression ( ε | elseif_expression_list )\n=> elseif_expression_list : elseif_expression elseif_expression_list\nelseif_expression_list\n\nepsilon\n\n(ε | elseif_expression_list )\nAPPENDIX E. GRAMMAR TRANSFORMATIONS\n\nListing E.25: Refactoring of If Expressions\n\nFor the output expression lists, we need transformations that move the closing parenthesis to the outer right and that converge the remainder of the definitions. The recursion must be transformed into an iteration.\n\n```\n=> elseif_expression_list : ( elseif_expression )* elseif_expression\n5 => elseif_expression_list : ( elseif_expression )+\n if_expression : \"IF\" expression \"THEN\" expression ( ( elseif_expression )+ )? \"ELSE\"\n elseif_expression : \"IF\" expression \"THEN\" expression ( elseif_expression )* \"ELSE\"\n elseif_expression : \"if\" expression \"then\" expression ( elseif_expression )* \"else\"\n elseif_expression : \"if\" expression \"then\" expression ( elseif_expression )* \"else\"\n\nmassage(\n elseif_expression_list?,\n ( elseif_expression_list | EPSILON)\n in elseif_expression_list);\n5 distribute( in elseif_expression_list );\nvertical( in elseif_expression_list );\ndeyaccify( elseif_expression_list );\ninline( elseif_expression_list );\nmassage(\n elseif_expression+?,\n elseif_expression*)\nrenameT(\"IF\", \"if\");\nrenameT(\"THEN\", \"then\");\nrenameT(\"ELSEIF\", \"else\");\nrenameT(\"ELSE\", \"else\");\ninline( elseif_expression );\ninline( if_expression );\n```\n\n```\nListing E.25: Refactoring of If Expressions\n\nFor the output expression lists, we need transformations that move the closing parenthesis to the outer right and that converge the remainder of the definitions. The recursion must be transformed into an iteration.\n\n```\n\")\" | \",\" output_expression_list |\n expression ( \",\" output_expression_list |\n expression \")\"\n=> \")\" | ( ( expression ) \",\" output_expression_list |\n expression \")\"\n=> ( ( expression ) \",\" output_expression_list |\n expression \")\"\n5 => expression? \")\" | expression? \",\" output_expression_list\n=> ( expression? \",\" expression? \")\")\n=> ( expression? \",\" expression? // inlined and extracted again without \")\"\n=> expression? ( \",\" expression? \")\"\n\ndistribute( in output_expression_list );\nfactor(\n (\"\", output_expression_list) |\n (output_expression_list | EPSILON | expression )\",\" output_expression_list);\n5 factor(\n (\"\", output_expression_list | EPSILON | expression )\"\"),\n (EPSILON | expression )\"\"\n massage(\n (EPSILON | expression),\n expression?)\n vertical( in output_expression_list );\ndeyaccify( output_expression_list );\ninline( output_expression_list );\nextract( output_expression_list );\n```\nMatrix expression lists make up one choice of the production primary. The transformations needed form a common pattern.\n\n```\nexpression_list ( \"SEMICOLON\" matrix_expression_list)? => expression_list ( ε | \"SEMICOLON\" matrix_expression_list ) => ( expression_list \"SEMICOLON\" )* expression_list\n5 => expression_list ( \":;\" expression_list )* // transformations renameT and massage\n```\n\n```\nmassage(( \"SEMICOLON\" matrix_expression_list)? , (EPSILON | (\"SEMICOLON\" matrix_expression_list)));\ndistribute( in matrix_expression_list );\n5 vertical( in matrix_expression_list );\ndeyaccify(matrix_expression_list);\nrenameT(\"SEMICOLON\", \";\");\nmassage(( expression_list \";;\" )* expression_list ,\nexpression_list ( \";;\" expression_list)*);\ninline(matrix_expression_list);\n```\n\nThe production component_reference2 accounts for the main definition of component references we need to align with Modelica. The transformations lead to the following chain of definitions of component references of type 2:\n\n```\n(\"IDENT\" | \"OPERATOR\") array_subscripts? ( \".\" component_reference2 )?\n=> helper ( ε | \".\" component_reference2 ) // to not distribute the first choice\n=> helper | helper \".\" component_reference2\n5 => ( helper \".\" )* helper\n=> helper ( \".\" helper*)\n=> (\"IDENT\" | \"OPERATOR\") array_subscripts? ( \".\" (\"IDENT\" | \"OPERATOR\")\narray_subscripts? )*\n```\n\n```\nmassage(( \"IDENT\" | \"operator\") array_subscripts? ,\n(EPSILON | (\".\" component_reference2)));\n5 extract( helper:\n(\"IDENT\" | \"operator\") array_subscripts? );\ndistribute( in component_reference2 );\nvertical( in component_reference2 );\ndeyaccify(component_reference2);\nmassage(\n (helper \".\")* helper,\n helper (\".\" helper)*);\ninline(helper);\n10 inline(component_reference2);\n```\nThe for-or-expression lists, abbreviated \\texttt{for\\_or}, change in the following way:\n\n\\begin{verbatim}\nfor\\_or2: \\epsilon | expression (\",\" for\\_or2 )?\n\\Rightarrow for\\_or2: \\epsilon | expression ( \\epsilon | \"\", for\\_or2 )\n\\Rightarrow for\\_or2: expression? | expression \",\", for\\_or2\n\\Rightarrow for\\_or2: ( expression \",\", expression? \nfor\\_or: \\epsilon | expression ( \",\", ( expression \",\", expression? | \"FOR\" for\\_indices )\n\\Rightarrow for\\_or: (expression (\",\", ( expression \",\")* expression? | \"FOR\" for\\_indices ) )?\n\nmassage(\n(\"\", for\\_expression\\_list2)?,\n(EPSILON | \",\", for\\_expression\\_list2)));\ndistribute( in for\\_expression\\_list2 );\n5 massage(\n(EPSILON | expression).\nexpression?);\nvertical( in for\\_expression\\_list2 );\ndeyaccify(for\\_expression\\_list2);\n10 inline(for\\_expression\\_list2);\nmassage(\n(EPSILON | expression (\"\",\" ( expression \",\")* expression? | \"FOR\" for\\_indices ) )?),\n(expression (\"\", ( expression \",\")* expression? | \"FOR\" for\\_indices )?);\nrenameT(\"FOR\",\" for\\_or_indices\");\n\\end{verbatim}\n\nListing E.29: Refactoring of For-or-expression Lists\n\nThe upcoming XBGF file deals with function arguments. OpenModelica defines the function arguments through for-or-expression lists we have transformed in the previous listing. We will unfold the definition of for-or-expression lists into the function arguments as the Modelica specification does not know the limited form for-or-expression list for function arguments. The transformations form the following chain of definitions of function arguments:\n\n\\begin{verbatim}\nfor\\_expression\\_list named\\_arguments?\n\\Rightarrow ( expression (\",\" ( expression \",\")* expression? | \"for\" for\\_indices ) )?\n\\Rightarrow helper? ( \\epsilon | named\\_arguments )\n\\Rightarrow ( \\epsilon | helper ) ( \\epsilon | named\\_arguments )\n5 \\Rightarrow \\epsilon | helper | named\\_arguments | helper named\\_arguments\n\\Rightarrow ( helper | named\\_arguments | helper named\\_arguments )?\n\\Rightarrow helper | named\\_arguments | helper named\\_arguments // inline and extract without optional\n\\Rightarrow helper ( \\epsilon | named\\_arguments ) | named\\_arguments\n\\Rightarrow helper named\\_arguments? | named\\_arguments\n10 \\Rightarrow expression (\",\", ( expression \",\")* expression? | \"for\" for\\_indices )\nnamed\\_arguments? | named\\_arguments\n\nmassage(\nnamed\\_arguments?,\n(EPSILON | named\\_arguments)\nin function\\_arguments);\n5 unfold(for\\_expression\\_list in function\\_arguments);\nextract(\nhelper:\nexpression (\",\", ( expression \",\")* expression? | \"FOR\" for\\_indices )?\n);\n10 massage(\nhelper?,\n\\end{verbatim}\nListing E.30: Refactoring of Function Arguments\n\nThe following transformations deal with a production that is not a production of its own in the Modelica specification but part of the production primary, namely component_reference__function_call. The idea behind the transformations are listed next:\n\n\\[\n\\begin{align*}\n\\text{component_reference function_call_args?} & \\mid \\text{\"INITIAL\" \"(\" \")\"} \\\\\n\\Rightarrow & \\text{component_reference ( \\(\\epsilon\\) | function_call_args) | \"INITIAL\" \"(\" \")\"} \\\\\n\\Rightarrow & \\text{component_reference | component_reference function_call_args | \"INITIAL\" \"(\" \")\"} \\\\\n\\Rightarrow & \\text{component_reference | name function_call_args | \"INITIAL\" \"(\" \")\"}\n\\end{align*}\n\\]\n\nThe last transformation factors the function call arguments of the function calls beginning with a name and the keyword “der” to align the structure of the primary definitions.\n\nListing E.31: Refactoring of Function Call Arguments\nThe nonterminal \\texttt{function_argument} is not necessary in OpenModelica in the way it is used in Modelica. But to align the productions, we introduce such a nonterminal and define it solely by an expression. The new nonterminal is then folded into several productions where the Modelica specification uses the nonterminal.\n\n\\begin{verbatim}\nintroduce{\n function_argument: expression\n};\nfold(function_argument in named_argument);\nfold(function_argument in for_or_expression_list);\nfold(function_argument in function_arguments);\n\\end{verbatim}\n\nListing E.32: Refactoring of Function Expressions\n\nSimple expressions can be combined in OpenModelica to a larger extent. However, the core production of a simple expression agrees. Therefore, we shift the additional combinatorial possibilities into the definition of the nonterminal \\texttt{expression} and let the definition of the simple expressions be simply the generation of a simple expression. To inline the simple expressions, we need to eliminate the recursion.\n\n\\begin{verbatim}\nsimple_expr ( \"::\" simple_expression )? | \"IDENT\" \"as\" simple_expression\n⇒ simple_expr ( ε | \"::\" simple_expression ) | \"IDENT\" \"as\" simple_expression\n⇒ simple_expr | simple_expr \"::\" simple_expression | \"IDENT\" \"as\" simple_expression\n⇒ simple_expr | ( simple_expr \"::\" | \"IDENT\" \"as\" ) simple_expression\n⇒ ( simple_expr \"::\" | \"IDENT\" \"as\" )\" simple_expr\n\\end{verbatim}\n\nListing E.33: Refactoring of Simple Expressions\n\nWe can eliminate two redundant choices within the definition of component references according to the lexer definition.\n\n\\begin{verbatim}\nvertical( in primary );\nremoveV( primary:\n \"UNSIGNED_INTEGER\"\n); horizontal( in primary );\nrenameT(\"UNSIGNED_REAL\", \"UNSIGNED_NUMBER\");\nvertical( in component_reference );\nremoveV( component_reference:\n \"WILD\"\n); removeV( component_reference:\n \"ALLWILD\"\n\\end{verbatim}\nE.3 OpenModelica vs. JModelica\n\nThe first two XBGF files eliminate the production `name` in each grammar as it is defined in the same way as component references and was only introduced because of Modelica. In neither grammar, names were incorporated in the grammar as an explicit production.\n\n```plaintext\nequate(name, component_reference);\n```\n\nListing E.35: Elimination of Names in OpenModelica\n\n```plaintext\nequate(name, component_reference);\n```\n\nListing E.36: Elimination of Names in JModelica\n\nThe first two transformations partly revert an inlining we applied to JModelica to align the production `function_argument`. We extract the function expression again and fold the definition of function call arguments into it to converge the production `part_eval_function_expression`. The last three transformations introduce the notion of for-or-expression lists though they are defined only by function arguments. It eliminates an exclusive Modelica nonterminal and aligns the definition of primaries more.\n\n```plaintext\nextract(\n part_eval_function_expression:\n \"function\" component_reference \"(\" function_arguments? \")\"\n);\nfold(function_call_args);\nintroduce(\n for_or_expression_list:\n function_arguments\n);\nfold(for_or_expression_list in primary);\nunfold(function_arguments in for_or_expression_list);\n```\n\nListing E.37: Refactoring of JModelica\nBibliography\n\n\n"}}},{"rowIdx":69,"cells":{"id":{"kind":"string","value":"32e1e474743f21cfd0d4aabb4f3f99692e7aadd7"},"text":{"kind":"string","value":"Serial Attached SCSI RAID Controllers Installation and User's Guide\n\nCDP-00283-01-A Rev. A\nIssue: July 15, 2013\n### Revision History\n\n<table>\n<thead>\n<tr>\n<th>Issue</th>\n<th>Issue Date</th>\n<th>Details of Change</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1.03</td>\n<td>July 15, 2013</td>\n<td>Adaptec Firmware/BIOS/Drivers/Utilities Version 1.03</td>\n</tr>\n</tbody>\n</table>\nContents\n\nAdaptec by PMC Product Support ......................................................................................................................... 8\nLimited 3-Year Hardware Warranty .......................................................................................................................... 10\nRegulatory Compliance Statements ..................................................................................................................... 11\n\n1 About This Guide .................................................................................................................................................. 14\n What You Need to Know Before You Begin ......................................................................................................... 14\n Terminology Used in this Guide ............................................................................................................................ 14\n How to Find More Information .............................................................................................................................. 14\n\n2 Kit Contents and System Requirements ............................................................................................................. 16\n Kit Contents .......................................................................................................................................................... 16\n System Requirements ......................................................................................................................................... 16\n\n3 About Your RAID Controller .............................................................................................................................. 17\n Standard RAID Controller Features ...................................................................................................................... 17\n Array-level Features ......................................................................................................................................... 17\n Advanced Data Protection Suite ............................................................................................................................ 17\n Adding a Flash Backup Module .............................................................................................................................. 18\n Upgrading the Controller Firmware ..................................................................................................................... 18\n About the Adaptec RAID 7805/7805Q .................................................................................................................... 19\n About the Adaptec RAID 71605/71605Q .................................................................................................................. 20\n About the Adaptec RAID 71605E ........................................................................................................................... 21\n About the Adaptec RAID 71685 ............................................................................................................................. 22\n About the Adaptec RAID 72405 ............................................................................................................................. 23\n About the Adaptec RAID 78165 ............................................................................................................................. 24\n\n4 Getting Started .................................................................................................................................................... 25\n Choosing a RAID Level ........................................................................................................................................ 25\n Selecting Disk Drives and Cables .......................................................................................................................... 25\n Disk Drives ....................................................................................................................................................... 25\n Cables ............................................................................................................................................................... 25\n Replacing the Full-Height Bracket with a Low-Profile Bracket ............................................................................ 26\n Installation Options ........................................................................................................................................... 27\n Basic Installation Steps ...................................................................................................................................... 27\n Installing with an Operating System ................................................................................................................... 28\n Installing on an Existing Operating System ....................................................................................................... 28\n\n5 Installing the Controller and Disk Drives ......................................................................................................... 29\n Before You Begin .............................................................................................................................................. 29\n Installing the Controller ................................................................................................................................... 29\n Installing a RAID Controller without Zero Maintenance Cache Protection .................................................... 29\n Installing a RAID Controller with Zero Maintenance Cache Protection ......................................................... 30\n Connecting Disk Drives to Your Controllers ....................................................................................................... 33\n Connecting Drives Directly to the Controller ........................................................................................................ 33\n Connecting Drives to a System Backplane .......................................................................................................... 33\n Connecting Solid State Drives (SSDs) .................................................................................................................... 33\n Connecting External Devices ............................................................................................................................... 34\n Next Steps ......................................................................................................................................................... 35\n\n6 Creating a Bootable Array ................................................................................................................................. 36\n Setting the Boot Controller .................................................................................................................................. 36\n Creating an Array ................................................................................................................................................ 36\n Creating an Array with the ARC Utility .................................................................................................................. 36\n Creating an Array with maxView Storage Manager ............................................................................................ 37\n Making Your Array Bootable .................................................................................................................................. 39\nAppendix A Introduction to SAS\n\nTerminology Used in This Appendix\n\nWhat is SAS?\nHow Do SAS Devices Communicate?\nWhat’s a Phy?\nWhat’s a SAS Port?\nWhat’s a SAS Address?\nWhat’s a SAS Connector?\nAdaptec by PMC Product Support\nIf you have questions about installing or using your Adaptec by PMC product, check this document first—you will find answers to most of your questions. If you need further assistance, use the support options listed below. To expedite your service, have your computer in front of you.\n\nNote: The phone numbers below are subject to change. Please visit the Support section of www.adaptec.com for the most up to date contact information.\n\nTechnical Support Identification (TSID) Number\n\n- Before contacting Technical Support, you need your product unique TSID number. The TSID number identifies your product and support status.\n- The TSID number is included on a white, bar-coded label, like this example:\n\n![TSID Number Example]\n\n- It’s recommended that you register your product so that you have easy access to your TSID when contacting product support.\n\nSelf Help and Support in English\n\n- Search the Adaptec Support Knowledgebase (ASK) at ask.adaptec.com for articles, troubleshooting tips, and frequently asked questions for your product.\n- For support via e-mail, submit your question at ask.adaptec.com.\n- To speak with a Technical Support Specialist, call +1 408 934 7274 or +49 89 4366 5544 or +44 845 266 8773.\n\nTechnische Informationen und Support in Deutsch\n\n- Besuchen Sie unsere Webseite www.adaptec.com/de-de\n- Suchen Sie in der Adaptec Support Knowledgebase (ASK) unter ask-de.adaptec.com nach Artikeln, Tipps zur Fehlerbehebung und häufig gestellten Fragen zu Ihrem Produkt.\n- Support per Email erhalten Sie unter ask-de.adaptec.com.\n- Für telefonischen Support wählen Sie +49 89 4366 5522.\n\nТехническая поддержка и информация на русском языке\n\n- Посещаете наш сайт www.adaptec.com/ru-ru/.\n- База знаний Adaptec (ASK) на сайте ask-ru.adaptec.com ask-ru.adaptec.com — статьи, советы по устранению неисправностей и часто задаваемые вопросы о Вашем продукте.\n- Для поддержки по электронной почте отправьте Ваш запрос на сайте ask-ru.adaptec.com.\n- Чтобы обратиться к специалисту технической поддержки по телефону, звоните на +7 499 918 7200 или +49 89 4366 5555.\n\n日本語での技術情報とサポート\n\n- 弊社のウェブサイト、www.adaptec.com/ja-jaをご覧ください。\n- ask.adaptec.co.jp のAdaptec Support Knowledgebase (ASK) でお使いの製品の情報、トラブルシューティングのヒント、よくある質問を検索してください。\n- Eメールでのサポートには ask.adaptec.co.jp から質問を送ってください。\nInformation Technique et d'assistance en Français\n\n- Rechercher dans le base de connaissances Adaptec (ASK) [ask-fr.adaptec.com](http://ask-fr.adaptec.com) pour des articles, conseils de dépannage et les questions fréquemment posées pour votre produit.\nLimited 3-Year Hardware Warranty\n\n1. PMC-Sierra, Inc. (\"PMC-Sierra\") warrants to the purchaser of this product that it will be free from defects in material and workmanship for a period of three (3) years from the date of purchase. If the product should become defective within the warranty period, PMC-Sierra, at its option, will repair or replace the product, or refund the purchaser’s purchase price for the product, provided it is delivered at the purchaser’s expense to an authorized PMC-Sierra service facility or to PMC-Sierra.\n\n2. Repair or replacement parts or products will be furnished on an exchange basis and will either be new or reconditioned and will be subject to original warranty term. All replaced parts or products shall become the property of PMC-Sierra. This warranty shall not apply if the product has been damaged by accident, misuse, abuse or as a result of unauthorized service or parts.\n\n3. Warranty service is available to the purchaser by delivering the product during the warranty period to an authorized PMC-Sierra service facility or to PMC-Sierra and providing proof of purchase price and date. The purchaser shall bear all shipping, packing, and insurance costs and all other costs, excluding labor and parts, necessary to effectuate repair, replacement or refund under this warranty.\n\n4. For more information on how to obtain warranty service, write or telephone:\n • Americas PMC-Sierra, Inc. at 1380 Bordeaux Drive Sunnyvale, CA 94089 USA, +1 408 934-7274\n • EMEA PMC-Sierra, at Lise-Meitner-Strasse 7, 85737 Ismaning, Germany, +49 89 43665544\n • Asia Pacific PMC-Sierra, at PO Box 110, Peakhurst NSW 2210, Australia, +61 2 8212-5531\n • Japan PMC-Sierra, at Tokumasu-Building 4F, 5-5-5, Higashinakano, Nakano-ku, Tokyo 164-0003, Japan, 03-3367-3970 (fax).\n\n5. THIS LIMITED WARRANTY DOES NOT EXTEND TO ANY PRODUCT WHICH HAS BEEN DAMAGED AS A RESULT OF ACCIDENT, MISUSE, ABUSE, OR AS A RESULT OF UNAUTHORIZED SERVICE OR PARTS.\n\n6. THIS WARRANTY IS IN LIEU OF ALL OTHER EXPRESS WARRANTIES WHICH NOW OR HEREAFTER MIGHT OTHERWISE ARISE RESPECT TO THIS PRODUCT. IMPLIED WARRANTIES, INCLUDING THOSE OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT SHALL (A) HAVE NO GREATER DURATION THAN 3 YEARS FROM THE DATE OF PURCHASE, (B) TERMINATE AUTOMATICALLY AT THE EXPIRATION OF SUCH PERIOD AND (C) TO THE EXTENT PERMITTED BY LAW BE EXCLUDED. IN THE EVENT THIS PRODUCT BECOMES DEFECTIVE DURING THE WARRANTY PERIOD, THE PURCHASER’S EXCLUSIVE REMEDY SHALL BE REPAIR, REPLACEMENT OR REFUND AS PROVIDED ABOVE. INCIDENTAL OR CONSEQUENTIAL DAMAGES, INCLUDING WITHOUT LIMITATION LOSS OF DATA, ARISING FROM BREACH OF ANY EXPRESS OR IMPLIED WARRANTY ARE NOT THE RESPONSIBILITY OF PMC-SIERRA AND, TO THE EXTENT PERMITTED BY LAW, ARE HEREBY EXCLUDED BOTH FOR PROPERTY DAMAGE, AND TO THE EXTENT NOT UNCONSCIONABLE, FOR PERSONAL INJURY DAMAGE.\n\n7. WITHIN THE US, SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES FOR CONSUMER PRODUCTS, AND SOME STATES DO NOT ALLOW LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS, SO THE ABOVE LIMITATION OR EXCLUSIONS MAY NOT APPLY TO YOU.\n\n8. THIS WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS, AND YOU MAY ALSO HAVE OTHER RIGHTS WHICH VARY DEPENDING ON WHERE YOU RESIDE.\n\n9. FOR AUSTRALIA RESIDENTS, IF THE PRODUCT SHOULD BECOME DEFECTIVE WITHIN THE WARRANTY PERIOD, PMC-SIERRA, AT ITS OPTION, WILL REPAIR OR REPLACE THE PRODUCT, OR REFUND THE PURCHASER’S PURCHASE FOR THE PRODUCT, PROVIDED IT IS DELIVERED AT THE PURCHASER’S EXPENSE BACK TO THE PLACE OF PURCHASE AFTER PMC-SIERRA TECHNICAL SUPPORT HAS ISSUED AN INCIDENT NUMBER. IN ADDITION TO THE WARRANTIES SET FORTH HEREIN, OUR GOODS COME WITH GUARANTEES THAT CANNOT BE EXCLUDED UNDER THE AUSTRALIAN CONSUMER LAW. YOU ARE ENTITLED TO A REPLACEMENT OR REFUND FOR A MAJOR FAILURE AND FOR COMPENSATION FOR ANY OTHER REASONABLY FORESEEABLE LOSS OR DAMAGE. YOU ARE ALSO ENTITLED TO HAVE THE GOODS REPAIRED OR REPLACED IF THE GOODS FAIL TO BE OF ACCEPTABLE QUALITY AND THE FAILURE DOES NOT AMOUNT TO A MAJOR FAILURE.\nRegulatory Compliance Statements\n\nFederal Communications Commission Radio Frequency Interference Statement\n\nAttention: Changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.\n\nThis equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy, and if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. However, if this equipment does cause interference to radio or television equipment reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:\n\n- Reorient or relocate the receiving antenna.\n- Increase the separation between equipment and receiver.\n- Connect the equipment to an outlet on a circuit different from that to which the receiver is connected.\n- Consult the dealer or an experienced radio/television technician for help.\n- Use a shielded and properly grounded I/O cable and power cable to ensure compliance of this unit to the specified limits of the rules.\n\nThis device complies with part 15 of the FCC rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference and (2) this device must accept any interference received, including interference that may cause undesired operation.\n\nUL Compliance Statement\n\nAdaptec by PMC products are tested and listed by Underwriters Laboratories, Inc. to UL 60950-1 Second Edition and IEC-60950-1 Second Edition standards, file numbers E175975. Adaptec by PMC products are for use only with UL listed ITE.\n\n<table>\n<thead>\n<tr>\n<th>Tested to Comply With FCC Standards</th>\n<th>Use only with the listed ITE:</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>PMC-Sierra, Inc.</td>\n<td>ASR-7805/ASR-7805Q/ASR-71605/</td>\n</tr>\n<tr>\n<td></td>\n<td>ASR-71605E/ASR-71605Q/ASR-71685/</td>\n</tr>\n<tr>\n<td></td>\n<td>ASR-72405/ASR-78165/</td>\n</tr>\n<tr>\n<td></td>\n<td>AFM-700</td>\n</tr>\n</tbody>\n</table>\n\nFOR HOME OR OFFICE USE\nEuropean Union Compliance Statement\n\nThis Information Technology Equipment has been tested and found to comply with EMC Directive 89/336/EEC, as amended by 92/31/EEC and 93/68/EEC, in accordance with:\n\n - Class B ITE radiated and conducted emissions\n - EN61000-4-2 (2009) Electrostatic discharge: ±4 kV contact, ±8 kV air\n - EN61000-4-3 (2010) Radiated immunity: 3V/m\n - EN61000-4-4 (2004) Electrical fast transients/burst: ±1 kV AC, ±0.5 kV I/O\n - EN61000-4-5 (2006) Surges: ±1 kV differential mode, ±2 kV common mode\n - EN61000-4-6 (2009) Conducted immunity: 3 V\n - EN61000-4-11 (2004) Supply dips and variations: 30% and 100%\n- EN50581 (2012) Technical Documentation:\n - For the assessment of electrical and electronic products with respect to the restriction of hazardous substances\n\nIn addition, all equipment requiring U.L. listing has been found to comply with EMC Directive 73/23/EEC as amended by 93/68/EEC in accordance with EN60950 with amendments A1, A2, A3, A4, A11.\n\nAustralian/New Zealand Compliance Statement\n\nThis device has been tested and found to comply with the limits for a Class B digital device, pursuant to the Australian/New Zealand standard AS/NZS 3548 set out by the Spectrum Management Agency.\n\nCanadian Compliance Statement\n\nThis Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations.\n\nCet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.\n\nJapanese Compliance (Voluntary Control Council Initiative)\n\nThis equipment complies to class B Information Technology equipment based on VCCI (Voluntary Control Council for Interface). This equipment is designed for home use but it may causes radio frequency interference problem if used too near to a television or radio. Please handle it correctly per this documentation.\n\nKorean Compliance (KCC) Statement\n\nAdaptec by PMC products are tested and certified by KCC:\nKCC-REM-KHK-ASR-7xxx5\n\nThe above certification covers the following series:\n\n- ASR-7805, ASR-7805Q, ASR-71605\n- ASR-71605E, ASR-71605Q\n- ASR-71685, ASR-72405, ASR-78165\n- AFM-700\nThis equipment is home use (Class B) electromagnetic wave suitability equipment and to be used mainly at home and it can be used in all areas.\n1 About This Guide\n\nThis Installation and User's Guide explains how to install your Adaptec® by PMC™ RAID controller. It also describes the utilities included in your controller kit, and provides a basic overview of Serial Attached SCSI (SAS) and Redundant Array of Independent Disk (RAID) technology.\n\nThese Adaptec Serial Attached SCSI RAID (ASR) controller models are described in this guide:\n\n- ASR-7805, ASR-7805Q\n- ASR-71605, ASR-71605E, ASR-71605Q\n- ASR-71685\n- ASR-72405\n- ASR-78165\n\nWhat You Need to Know Before You Begin\n\nYou should be familiar with computer hardware, data storage, RAID technology, and SAS and Serial ATA (SATA) technology. (For more information about SAS technology, see Introduction to SAS on page 62.) You should also be familiar with direct-attached storage (DAS) concepts and technology.\n\nNote: Because this guide covers multiple Adaptec RAID products, some of the features and functions described may not be available for your controller. For more information, see About Your RAID Controller on page 17.\n\nTerminology Used in this Guide\n\nBecause you can use your Adaptec RAID controller to manage data storage in a variety of configurations, the generic term “storage space” is used to refer to controller(s) and disk drives being managed with Adaptec maxView Storage Manager™ (called simply maxView Storage Manager in the remainder of this guide) or the other utilities described in this guide.\n\nMany of the terms and concepts referred to in this guide are known to computer users by multiple names. This guide uses these terms:\n\n- Controller (also known as adapter, board, or card)\n- Disk drive (also known as hard disk, hard drive, or hard disk drive)\n- Solid State Drive (also known as SSD or non-rotating storage media)\n- Enclosure (also known as a RAID enclosure, storage enclosure, or disk drive enclosure)\n- Array (also known as a container, logical device, or logical drive)\n\nNote: maxView Storage Manager refers to arrays as logical drives. Your RAID controller creates arrays, which your operating system (and maxView Storage Manager) recognizes as logical drives. For more information, refer to the maxView Storage Manager User’s Guide on the Adaptec Installation DVD.\n\nHow to Find More Information\n\nYou can find more information about your Adaptec RAID controller and the software and utilities included with it by referring to these documents:\n\n- Readme.txt—Includes updated product information and known issues; located on the Adaptec Installation DVD.\n- maxView Storage Manager User’s Guide—Describes how to install and use the maxView Storage Manager software (see About maxView Storage Manager on page 57) to manage your direct attached storage; located on the Adaptec Installation DVD.\n- maxView Storage Manager Online Help—Describes how to use the maxView Storage Manager software; accessible from the main window of maxView Storage Manager.\n- *Adaptec RAID Controller Command Line Utility User’s Guide*—Describes how to use the included Adaptec RAID Controller Configuration (ARCCONF) command line utility (see *About the Adaptec RAID Controller Configuration Utility* on page 57) to perform basic array and configuration management functions; located on the Adaptec Installation DVD.\n2 Kit Contents and System Requirements\n\nThis chapter lists the contents of your Adaptec RAID controller kit and the system requirements that must be met for you to successfully install and use your controller.\n\nKit Contents\n\n- Adaptec RAID controller\n- Adaptec Installation DVD (bootable), including controller drivers, Adaptec maxView Storage Manager, ARCCONF command line utility, and documentation\n- Cables (Not included in Adaptec ‘Single’ product. If your kit includes cables, the type and quantity vary—for more information, see Cables on page 25.)\n- (Select models only) Low-profile bracket\n- Adaptec Serial Attached SCSI RAID Controllers Quick Start Guide (on the installation DVD)\n\nSystem Requirements\n\n- PC-compatible computer with Intel Pentium, or equivalent, processor\n- Motherboard with these features:\n - Support for multi-function devices where one of the devices is a PCI bridge\n - Large memory-mapped address ranges\n Refer to the Readme file on the Adaptec Installation DVD for additional motherboard compatibility information.\n- One of these operating systems:\n - Red Hat® Enterprise Linux 6.3, 5.9 (32-bit and 64-bit)\n - SuSE Linux Enterprise Server 11, 10 (32-bit and 64-bit)\n - FreeBSD 9.1, 9.0 (32-bit and 64-bit)\n - Debian Linux 6 (32-bit and 64-bit)\n - Ubuntu Linux 12, 11, 10 (32-bit and 64-bit)\n - Fedora Linux 18, 17 (32-bit and 64-bit)\n - CentOS 6.3, 5.9 (32-bit and 64-bit)\n - Solaris 10, Solaris 11 Express\n - VMware ESXi 5.1, VMware ESX 4.1 Classic\n - Citrix XenServer 6.1\n- 2 GB of RAM minimum\n- Available compatible PCIe slot (depending on your controller model—see the descriptions in About Your RAID Controller on page 17)\n- 350 MB of free disk drive space\n- 16-bit SVGA color monitor with a resolution of at least 800 x 600\n- DVD-ROM drive\n- USB flash drive or CD burner, for creating driver disks and bootable media\nAbout Your RAID Controller\n\nThis chapter provides an overview of the features of your Adaptec RAID controller.\n\nStandard RAID Controller Features\n\n- Support for SAS disk drives, SATA/SATA II disk drives, and SATA and SAS Solid State Drives (SSDs)\n- Flash ROM for updates to controller firmware, BIOS, and the Adaptec RAID Configuration utility\n- Disk drive hot-swapping\n- Event logging and broadcasting, including email notification messages\n- Multiple options for creating and managing RAID arrays—a browser-based software application (maxView Storage Manager), a BIOS-based utility (ARC), a command line utility (ARCCONF) (see Managing Your Storage Space on page 57)\n- Native command queuing (NCC), which lets disk drives arrange commands into the most efficient order for optimum performance\n- Support for disk drive enclosures with SES2 enclosure management hardware\n- Support for a flash backup module (see Adding a Flash Backup Module on page 18)\n- Support for Adaptec maxCache™ SSD read and write caching (see Modifying Cache Settings on page 76)\n\n**Note:** Adaptec maxCache is supported on Adaptec Series Q controllers only.\n\n- Power-management of disk drives in your storage space to reduce cooling and electricity costs (see Modifying Power Management Settings on page 76)\n- Audible alarm\n- I/O statistics logging\n\nArray-level Features\n\n**Note:** Not all features are supported by all controllers. For more information, see the maxView Storage Manager User’s Guide.\n\n- Support for RAID 0, RAID 1, RAID 5, RAID 10, RAID 50, and simple volumes\n- Support for hybrid RAID 1 and RAID 10 arrays comprised of hard drives and Solid State Drives (SSDs)\n- Support for hot spares (global and dedicated)\n- Support for automatic failover, so arrays are automatically rebuilt when a failed drive is replaced (applies to redundant arrays in SES2- or SAF-TE-enabled disk drive enclosures only)\n- Optimized disk utilization, which ensures that the full capacity of all disk drives can be used, even if the disk drives vary in size\n- Online capacity expansion, so you can increase the capacity of an array without recreating it\n- Support for array migration from one RAID level to another\n\nAdvanced Data Protection Suite\n\n- Copyback Hot Spare—You can use this feature to move data from a hot spare back to its original location after a failed disk drive is replaced.\n- Striped Mirror (RAID 1E)—A RAID 1 Enhanced array is similar to a RAID 1 array except that data is both mirrored and striped, and more disk drives can be included.\n- Dual Drive Failure Protection (RAID 6)—A RAID 6 array is similar to a RAID 5 array except that it includes two independent sets of parity data instead of one.\n- Dual Drive Failure Protection (RAID 60)—A RAID 60 array is similar to a RAID 50 array except that it includes four independent sets of parity data instead of two.\nAdding a Flash Backup Module\n\nThis table shows the flash backup module (or “zero maintenance cache protection”) supported by your Adaptec RAID controller. To purchase a flash backup module, refer to the Adaptec Web site at www.adaptec.com.\n\n<table>\n<thead>\n<tr>\n<th>RAID Controller</th>\n<th>Flash Module</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Adaptec RAID 7805/Adaptec RAID 71605/Adaptec RAID 71685/Adaptec RAID 72405/Adaptec RAID 78165</td>\n<td>Adaptec Flash Backup Module AFM-700 with Supercapacitor Card (optional)</td>\n</tr>\n<tr>\n<td>Adaptec RAID 7805Q/Adaptec RAID 71605Q</td>\n<td>Adaptec Flash Backup Module AFM-700 with Supercapacitor Card (pre-installed)</td>\n</tr>\n</tbody>\n</table>\n\nUpgrading the Controller Firmware\n\nTo upgrade the firmware on your Adaptec RAID controller, follow the instructions in Using the Adaptec Flash Utility on page 83. You can also upgrade the controller firmware with maxView Storage Manager or the ARCCONF command-line utility. Refer to the maxView Storage Manager User’s Guide and the Adaptec Command Line Interface User’s Guide for more information. If the firmware upgrade is unsuccessful, follow the instructions in Resetting the Controller on page 61.\nAbout the Adaptec RAID 7805/7805Q\n\nThe Adaptec RAID 7805/7805Q is a SAS RAID controller with these features:\n\n- 2 internal mini-SAS HD connectors\n- Ext. Alarm connector\n- HDA mode connector\n- Daughterboard connector\n- PCIe x8 connector\n- Mounting bracket\n\n<table>\n<thead>\n<tr>\n<th>Feature</th>\n<th>Specification</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Form Factor</td>\n<td>Low-profile MD2</td>\n</tr>\n<tr>\n<td>Bus compatibility</td>\n<td>PCIe Gen3</td>\n</tr>\n<tr>\n<td>PCIe bus width</td>\n<td>x8</td>\n</tr>\n<tr>\n<td>Data transfer rate</td>\n<td>6 Gb/s per port</td>\n</tr>\n<tr>\n<td>Phys (Unified Serial Ports)</td>\n<td>8</td>\n</tr>\n<tr>\n<td>Standard cache</td>\n<td>1024 MB DDR3</td>\n</tr>\n<tr>\n<td>Connectors, internal</td>\n<td>2 mini-SAS HD x4 (SFF-8643)</td>\n</tr>\n<tr>\n<td>Maximum number of disk drives</td>\n<td>8 direct-attached (or up to 256 with expanders)</td>\n</tr>\n<tr>\n<td>maxCache SSD support</td>\n<td>7805Q: Up to 8 solid state drives, 2TB capacity, max. See the maxCache compatibility list at <a href=\"http://www.adaptec.com/compatibility\">www.adaptec.com/compatibility</a>.</td>\n</tr>\n<tr>\n<td>Enclosure Support</td>\n<td>IBPI and SGPIO (Serial General Purpose Input/Output)</td>\n</tr>\n<tr>\n<td>Onboard speaker</td>\n<td>Yes</td>\n</tr>\n<tr>\n<td>Zero Maintenance Cache Protection Module</td>\n<td>Adaptec Flash Backup Module AFM-700 (7805: optional, sold separately; 7805Q: standard, pre-installed)</td>\n</tr>\n</tbody>\n</table>\nAbout the Adaptec RAID 71605/71605Q\n\nThe Adaptec RAID 71605/71605Q is a SAS RAID controller with these features:\n\n- **Form Factor**: Low-profile MD2\n- **Bus compatibility**: PCIe Gen3\n- **PCIe bus width**: x8\n- **Data transfer rate**: 6 Gb/s per port\n- **Phys (Unified Serial Ports)**: 16\n- **Standard cache**: 1024 MB DDR3\n- **Connectors, internal**: 4 mini-SAS HD x4 (SFF-8643)\n- **Maximum number of disk drives**: 16 direct-attached (or up to 256 with expanders)\n- **maxCache SSD support**: 71605Q: Up to 8 solid state drives, 2TB capacity, max. See the maxCache compatibility list at [www.adaptec.com/compatibility](http://www.adaptec.com/compatibility).\n- **Enclosure Support**: IBPI and SGPIO (Serial General Purpose Input/Output)\n- **Onboard speaker**: Yes\n- **Zero Maintenance Cache Protection Module**: Adaptec Flash Backup Module AFM-700 (71605: optional, sold separately; 71605Q: standard, pre-installed)\nAbout the Adaptec RAID 71605E\n\nThe Adaptec RAID 71605E is a SAS RAID controller with these features:\n\n- 4 internal mini-SAS HD connectors\n- Ext. Alarm connector\n- HDA mode connector\n- CN0, CN1, CN2, CN3\n- PCIe x8 connector\n- Mounting bracket\n\n<table>\n<thead>\n<tr>\n<th>Specification</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Form Factor</td>\n<td>Low-profile MD2</td>\n</tr>\n<tr>\n<td>Bus compatibility</td>\n<td>PCIe Gen3</td>\n</tr>\n<tr>\n<td>PCIe bus width</td>\n<td>x8</td>\n</tr>\n<tr>\n<td>Data transfer rate</td>\n<td>6 Gb/s per port</td>\n</tr>\n<tr>\n<td>Phys (Unified Serial Ports)</td>\n<td>16</td>\n</tr>\n<tr>\n<td>Standard cache</td>\n<td>256 MB DDR3</td>\n</tr>\n<tr>\n<td>Connectors, internal</td>\n<td>4 mini-SAS HD x4 (SFF-8643)</td>\n</tr>\n<tr>\n<td>Maximum number of disk drives</td>\n<td>16 direct-attached (or up to 256 with expanders)</td>\n</tr>\n<tr>\n<td>Enclosure Support</td>\n<td>IBPI and SGPIO (Serial General Purpose Input/Output)</td>\n</tr>\n<tr>\n<td>Onboard speaker</td>\n<td>Yes</td>\n</tr>\n<tr>\n<td>Zero Maintenance Cache Protection Module</td>\n<td>No</td>\n</tr>\n</tbody>\n</table>\nAbout the Adaptec RAID 71685\n\nThe Adaptec RAID 71685 is a SAS RAID controller with these features:\n\n- Full Height, Half Length Form Factor\n- PCIe Gen3 Bus compatibility\n- x8 PCIe bus width\n- 6 Gb/s per port Data transfer rate\n- 24 Phys (Unified Serial Ports)\n- 1024 MB DDR3 Standard cache\n- 4 mini-SAS HD x4 (SFF-8643) Connectors, internal\n- 2 mini-SAS HD x4 (SFF-8644) Connectors, external\n- 24 direct-attached (or up to 256 with expanders) Maximum number of disk drives\n- IBPI and SGPIO (Serial General Purpose Input/Output) Enclosure Support\n- Yes Onboard speaker\n- Adaptec Flash Backup Module AFM-700 (optional, sold separately) Zero Maintenance Cache Protection Module\nAbout the Adaptec RAID 72405\n\nThe Adaptec RAID 72405 is a SAS RAID controller with these features:\n\n- 4 internal mini-SAS HD connectors\n- 2 internal mini-SAS HD connectors\n- HDA mode connector\n- Ext. Alarm connector\n- Daughterboard connector\n- PCIe x8 connector\n- Mounting bracket\n\n<table>\n<thead>\n<tr>\n<th>Feature</th>\n<th>Specification</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Form Factor</td>\n<td>Full Height, Half Length</td>\n</tr>\n<tr>\n<td>Bus compatibility</td>\n<td>PCIe Gen3</td>\n</tr>\n<tr>\n<td>PCIe bus width</td>\n<td>x8</td>\n</tr>\n<tr>\n<td>Data transfer rate</td>\n<td>6 Gb/s per port</td>\n</tr>\n<tr>\n<td>Phys (Unified Serial Ports)</td>\n<td>24</td>\n</tr>\n<tr>\n<td>Standard cache</td>\n<td>1024 MB DDR3</td>\n</tr>\n<tr>\n<td>Connectors, internal</td>\n<td>6 mini-SAS HD x4 (SFF-8643)</td>\n</tr>\n<tr>\n<td>Maximum number of disk drives</td>\n<td>24 direct-attached (or up to 256 with expanders)</td>\n</tr>\n<tr>\n<td>Enclosure Support</td>\n<td>IBPI and SGPIO (Serial General Purpose Input/Output)</td>\n</tr>\n<tr>\n<td>Onboard speaker</td>\n<td>Yes</td>\n</tr>\n<tr>\n<td>Zero Maintenance Cache Protection Module</td>\n<td>Adaptec Flash Backup Module AFM-700 (optional, sold separately)</td>\n</tr>\n</tbody>\n</table>\nAbout the Adaptec RAID 78165\n\nThe Adaptec RAID 78165 is a SAS RAID controller with these features:\n\n- 2 internal mini-SAS HD connectors\n- 2 external mini-SAS HD connectors\n- PCIe x8 connector\n- Mounting bracket\n- HDA mode connector\n- Ext. Alarm connector\n- Daughterboard connector\n- PCIe x8 connector\n\n**Note:** To provide optimal cooling for the Adaptec 78165 controller, it is recommended to provide air intake through the ventilated full-height bracket. For more information about cooling requirements, see *Environmental Specifications* on page 90.\n\n<table>\n<thead>\n<tr>\n<th>Specification</th>\n<th>Details</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Form Factor</td>\n<td>Low-profile MD2</td>\n</tr>\n<tr>\n<td>Bus compatibility</td>\n<td>PCIe Gen3</td>\n</tr>\n<tr>\n<td>PCIe bus width</td>\n<td>x8</td>\n</tr>\n<tr>\n<td>Data transfer rate</td>\n<td>6 Gb/s per port</td>\n</tr>\n<tr>\n<td>Phys (Unified Serial Ports)</td>\n<td>24</td>\n</tr>\n<tr>\n<td>Standard cache</td>\n<td>1024 MB DDR3</td>\n</tr>\n<tr>\n<td>Connectors, internal</td>\n<td>2 mini-SAS HD x4 (SFF-8643)</td>\n</tr>\n<tr>\n<td>Connectors, external</td>\n<td>4 mini-SAS HD x4 (SFF-8644)</td>\n</tr>\n<tr>\n<td>Maximum number of disk drives</td>\n<td>24 direct-attached (or up to 256 with expanders)</td>\n</tr>\n<tr>\n<td>Enclosure Support</td>\n<td>IBPI and SGPIO (Serial General Purpose Input/Output)</td>\n</tr>\n<tr>\n<td>Onboard speaker</td>\n<td>Yes</td>\n</tr>\n<tr>\n<td>Zero Maintenance Cache Protection Module</td>\n<td>Adaptec Flash Backup Module AFM-700 (optional, sold separately)</td>\n</tr>\n</tbody>\n</table>\n4 Getting Started\n\nThis chapter provides the basic information you need to set up your disk drives and arrays the way you want them. It describes the options you have for installing your Adaptec RAID controller and disk drives and creating arrays for storage. It also describes how to prepare your controller for installation into a low-profile computer cabinet.\n\nChoosing a RAID Level\n\nThis section provides a brief overview of the RAID levels supported by your Adaptec RAID controller, including the minimum and maximum number of disk drives required by each.\n\n- **RAID 0 (Non-redundant Array)**—Stripes data across multiple disk drives. Improved performance but no redundancy (see Non-redundant Arrays (RAID 0) on page 67).\n- **RAID 1 Array**—Created from two disk drives where one disk drive is a mirror of the other (the same data is stored on each disk drive). Redundancy, but reduced capacity (see RAID 1 Arrays on page 68).\n- **RAID 1E Array**—Similar to a RAID 1 array except that data is mirrored and striped, and more disk drives can be included (see RAID 1 Enhanced Arrays on page 68).\n- **RAID 5 Array**—Stripes data for improved performance and uses parity data to provide redundancy (see RAID 5 Arrays on page 70).\n- **RAID 10 Array**—Built from two or more equal-sized RAID 1 arrays, stripes and mirrors data across multiple disk drives. Redundancy and improved performance (see RAID 10 Arrays on page 69).\n- **RAID 50 Array**—Built from multiple disk drives configured as two or more RAID 5 arrays, stripes stored data and parity data across all disk drives (see RAID 50 Arrays on page 71).\n- **RAID 6 Array**—Similar to a RAID 5 array except that it includes two independent sets of parity data instead of one (see RAID 6 Arrays on page 72).\n- **RAID 60 Array**—Similar to a RAID 50 array except that it includes four independent sets of parity data instead of two (see RAID 60 Arrays on page 72).\n\nSee Comparing RAID Levels on page 73 to see how many disk drives you must connect to your RAID controller to support the RAID level you want.\n\nSelecting Disk Drives and Cables\n\n**Disk Drives**\n\nYour SAS controller supports SAS disk drives, SATA disk drives, and SATA and SAS Solid State Drives (SSDs). When selecting disk drives for your RAID array, ensure that all the disk drives have the same performance level. You can use different-sized disk drives in the array, but the array will be limited to the capacity of the smallest and slowest disk drive. For more information about arrays, refer to the maxView Storage Manager User's Guide or online Help. For more information about compatible disk drives, refer to the Adaptec Web site at www.adaptec.com/compatibility.\n\n**Cables**\n\nDepending on your requirements, you can use any of the cables listed below. Cable connectors are keyed so that you can't insert them incorrectly. For more information about cabling options for your RAID controller, visit the Adaptec Web site at www.adaptec.com.\n\n**Note:** We recommend using only Adaptec SAS cables.\nAdaptec SAS Adapter 7xxx5 Cables\n\nInternal mini-SAS HD to mini-SAS HD (SFF-8643 to SFF-8643)—Connects to a backplane or enclosure.\n\nExternal mini-SAS HD to mini-SAS HD (SFF-8644 to SFF-8644)—Connects to a backplane or enclosure.\n\nReplacing the Full-Height Bracket with a Low-Profile Bracket\n\nIf you are installing your Adaptec RAID controller into a low-profile computer cabinet, replace the original full-height bracket with the low-profile bracket included in your distribution kit. The full-height bracket is mounted on the front of the controller, the low-profile bracket is mounted on the back of the controller, as shown in the figure below.\n\n\n\nTo replace the full-height bracket with the low-profile bracket:\n\n1. Remove the full-height bracket from the controller board. The full-height bracket is installed on the front side of the controller, with the mounting screws inserted from the back of the controller, as shown in the Figure 1.\n Using a Phillips head screw driver, remove the mounting screws, as shown in Figure 2, then set the screws aside for use in the next step.\n2. Attach the low-profile bracket to the controller board. The low-profile bracket is installed on the **back** side of the controller, with the mounting screws inserted from the front of the controller, as shown in Figure 3.\n\nInsert the screws through the holes on the front of the controller, then fasten the screws to the bracket with a Phillips screwdriver.\n\n**Caution:** The mount points on the low-profile bracket have a smooth or flat side and a raised side that looks like a spacer (see Figure 3). Be sure to install the bracket with the flat side against the controller PCB and the raised side facing away from the PCB.\n\n**Caution:** The torque on the mounting screws should be a maximum of 3.0-4.0 lbf-in to avoid deformation. Be sure that the controller is not bent after attaching the low-profile bracket to the controller board.\n\n### Installation Options\n\nWhen you install your Adaptec RAID controller, you can choose to create a bootable array and then install your operating system and the controller driver on that array.\n\nAlternatively, you can complete a standard installation, where the controller driver is installed on an existing operating system.\n\n### Basic Installation Steps\n\nThis section describes the installation process. Follow the steps for the installation option you’ve chosen.\nInstalling with an Operating System\n\n1. Install and connect your controller and internal disk drives (see Installing the Controller and Disk Drives on page 29).\n If your controller has an external connector, you can connect external disk drives as well (or instead).\n\n2. Set the boot controller (see Setting the Boot Controller on page 36).\n\n3. Create a bootable array (see Creating an Array on page 36).\n\n4. Install your operating system and the controller driver (see Installing the Driver and an Operating System on page 40.)\n\n5. Install maxView Storage Manager and begin to manage your data storage (see Managing Your Storage Space on page 57).\n\nInstalling on an Existing Operating System\n\n1. Install and connect your controller and internal disk drives (see Installing the Controller and Disk Drives on page 29).\n If your controller has an external connector, you can connect external disk drives as well (or instead).\n\n2. Install the controller driver (see Installing the Driver on an Existing Operating System on page 52).\n\n3. Install maxView Storage Manager and begin to manage your data storage (see Managing Your Storage Space on page 57).\n5 Installing the Controller and Disk Drives\n\nThis chapter explains how to install your Adaptec RAID controller, and how to install and connect internal and external disk drives.\n\nBefore You Begin\n\n• Read Safety Information on page 89.\n• Familiarize yourself with your RAID controller’s physical features and the RAID levels that it supports (see Standard RAID Controller Features on page 17).\n• Ensure you have the right quantity of disk drives for the RAID level you want to use for your arrays (see Selecting Disk Drives and Cables on page 25).\n• If you are installing the RAID controller into a low-profile computer cabinet, replace the original full-height bracket with the low-profile bracket included in the kit (see Replacing the Full-Height Bracket with a Low-Profile Bracket on page 26).\n\nInstalling the Controller\n\nThis section describes how to install the Adaptec RAID controller into your computer cabinet. Adaptec RAID controllers come in two basic configurations: standard and zero maintenance cache protection with batteryless backup (ZMCP). ZMCP uses flash memory and a supercapacitor module to protect the cache without a battery.\n\nFollow one of these sets of instructions:\n• To install an Adaptec RAID controller without zero maintenance cache protection, see the next section.\n• To install an Adaptec RAID controller with zero maintenance cache protection, see Installing a RAID Controller with Zero Maintenance Cache Protection on page 30.\n\nCaution: Be sure to handle the controller by its bracket or edges only.\n\nInstalling a RAID Controller without Zero Maintenance Cache Protection\n\nTo install an Adaptec RAID controller without zero maintenance cache protection:\n\n1. Turn off your computer and disconnect the power cord. Open the cabinet, following the manufacturer’s instructions.\n\n2. Select an available PCIe expansion slot that’s compatible with your RAID controller and remove the slot cover, as shown below. (PCIe bus compatibility is marked to the controller figures in About Your RAID Controller on page 17.)\n3. Insert the RAID controller into the expansion slot and press down gently but firmly until it clicks into place. When installed properly, the RAID controller should appear level with the expansion slot. \n **Caution:** Touch a grounded metal object before handling the RAID controller.\n\n4. Secure the bracket in the expansion slot, using the retention device (for instance, a screw or lever) supplied with your computer.\n\n5. Prepare and install your internal disk drives, following the instructions in *Connecting Disk Drives to Your Controllers* on page 33.\n\n If you are not installing internal disk drives, close your computer cabinet, reattach the power cord, then continue with *Connecting External Devices* on page 34.\n\n### Installing a RAID Controller with Zero Maintenance Cache Protection\n\nAdaptec RAID controllers with zero maintenance cache protection (Adaptec Series Q controllers) include a flash module daughterboard and a supercapacitor module. The daughterboard is pre-installed on these controller. On Adaptec RAID controllers with *optional* zero maintenance cache protection (see *Adding a Flash Backup Module* on page 18), the daughterboard is user installed. The supercapacitor module is always user installed.\n\nThe following instructions describe how to install the supercapacitor module on a Series Q controller using the *mounting plate* method. It assumes that the daughterboard is already installed. Refer to the flyer, in the flash module distribution kit, for details about installing the daughterboard on the controller, as needed; the flyer also describes other supercapacitor installation options.\n\n**Warning:** Do NOT remove or insert a fully charged supercapacitor module. Always discharge the unit first to avoid damage to the controller or flash backup module. The factory ships with discharged units, so they are safe to install when you receive them. To ensure that an installed unit is discharged, switch your system OFF, then wait 5 minutes. After a dirty shutdown, wait 3 minutes after backup is complete, then remove the unit.\n\nTo install an Adaptec RAID controller with zero maintenance cache protection:\n\n1. Assemble the mounting plate and attach the supercapacitor module:\n a) Attach the full-height bracket and mounting clip to the mounting plate. The full-height bracket is installed on the front side of the mounting plate (the side with the bents), with the mounting screws inserted from the back, as shown in the figure below. (Be sure to attach the mounting plate to the bracket with recessed side at the bottom!) Attach the mounting clip to the front of the mounting plate with four (4) Phillips screws. The large friction clip should face the front of the mounting plate.\nb) Insert the supercapacitor module into the mounting clip. The supercapacitor module snaps securely into place between the large and small friction clips, as shown in the figure below. Be sure to orient the supercapacitor module such that the connecting cable faces the rear of the mounting plate.\n\nc) Set the mounting plate aside; continue with the steps below.\n\n2. Turn off your computer and disconnect the power cord. Open the cabinet, following the manufacturer’s instructions.\n\n3. Select an available PCIe expansion slot that’s compatible with your RAID controller and remove the slot cover, as shown in the figure below. (PCIe bus compatibility is marked on the controller figures in About Your RAID Controller on page 17.) Be sure to choose a slot in the backplane with an empty slot next to it; you will use the empty slot to install the supercapacitor mounting plate, after you install the controller. Remove the slot cover for the mounting plate, then continue with the next step.\n4. Insert the RAID controller into the expansion slot and press down gently but firmly until it clicks into place. When installed properly, the RAID controller should appear level with the expansion slot. Secure the bracket in the expansion slot, using the retention device (for instance, a screw or lever) supplied with your computer.\n\n **Caution:** Touch a grounded metal object before handling the RAID controller.\n\n5. Attach the supercapacitor module to the RAID controller by inserting the connector into the socket on the flash module daughterboard, as shown in the figure below. (The connector attaches to the socket in only one direction.) Use the included extender cable if you need extra length to reach the connector on the daughterboard.\n\n6. Install the mounting plate in the empty slot next to the controller, as shown in the next figure. After securing the mounting plate to the card cage, verify that the supercapacitor module and mounting plate sit above (and do not touch) the PCIe slot.\n\n7. Prepare and install your internal disk drives, following the instructions in *Connecting Disk Drives to Your Controllers* on page 33.\n\n If you are not installing internal disk drives, close your computer cabinet, reattach the power cord, then continue with *Connecting External Devices* on page 34.\n\n8. Restart your computer.\n\n The supercapacitor starts charging automatically. It should reach full charge in 5-6 minutes.\nConnecting Disk Drives to Your Controllers\n\nYou can connect SAS disk drives, SATA disk drives, and SATA and SAS Solid State Drives (SSDs) to your Adaptec RAID controller. (See www.adaptec.com/compatibility for a list of compatible drives.) There are no jumpers or switches to set before installation.\n\nIf you plan to build a bootable array, ensure that you install at least the minimum number disk drives required to support the RAID level you want. See Choosing a RAID Level on page 25 for more information.\n\n**Note:** Although you can connect both SAS and SATA disk drives to your SAS controller, we recommend that you do not combine SAS and SATA disk drives within the same array. See What is SAS? on page 62 for more information.\n\nYou have two connection options:\n\n- To connect directly to the controller, see the following section.\n- To connect to a backplane, see Connecting Drives to a System Backplane on page 33.\n\nTo connect Solid State Drives to your controller, see Connecting Solid State Drives (SSDs) on page 33.\n\nConnecting Drives Directly to the Controller\n\nIn a direct-attach connection, SAS or SATA disk drives are connected directly to a SAS card with SAS cables. The number of direct-attached disk drives is limited to four per internal SAS connector. (For more information about direct-attach connections, see How are Disk Drives Identified in SAS? on page 64.)\n\n1. Install your internal SAS or SATA disk drives, following the instructions in your system's documentation.\n2. Use internal mini-SAS HD cables to attach the disk drives to the controller, as required.\n3. When all internal disk drives have been installed and attached to the controller, close your computer cabinet, reattach the power cord, then continue with Connecting External Devices on page 34.\n\nConnecting Drives to a System Backplane\n\nIn a backplane connection, disk drives and SAS cards are attached to and communicate with each other through a system backplane.\n\nThe number of disk drives is limited to the number of slots available on the backplane. Some backplanes have embedded SAS expanders and can support up to 128 end devices. (For more information about backplane and expander connections, see How are Disk Drives Identified in SAS? on page 64.)\n\n1. Connect one or more internal SAS or SATA disk drives to the backplane. (Refer to your system's documentation for more information.)\n2. Use an internal mini-SAS HD cable to connect the controller to the backplane, as required.\n3. When all internal disk drives have been installed and connected, close your computer cabinet, reattach the power cord, then continue with Connecting External Devices on page 34.\n\nConnecting Solid State Drives (SSDs)\n\nTo connect a Solid State Drive to your controller, you can use a direct-attached connection or a backplane connection, as required. If your server does not have a standard 2.5-inch drive tray, you must use a bracket/SLED which enables the SSD to fit properly.\n\n**Note:** For Adaptec maxCache applications or hybrid RAID arrays (comprised of hard drives and SSDs) you can use any Solid State Drive on the compatibility list. See www.adaptec.com/compatibility for a list of compatible SSDs. Adaptec maxCache is supported on Adaptec Series Q controllers only.\n\nIn a direct-attach connection (described in the steps below), you connect SSDs directly to the controller with SAS cables (mini-SAS to SATA). In a backplane connection, use the appropriate cable for your backplane type (see Connecting Drives to a System Backplane on page 33 for more about backplane connections). For maxCache caching applications, you can connect a maximum of 8 maxCache-compatible SSDs to a controller. For RAID arrays, Adaptec controllers support a maximum of 256 drives, including SSDs (for details, see About Your RAID Controller on page 17).\n1. Install the SSDs in your server. For servers with a standard 2.5-inch drive tray, install the SSD directly into the tray. If your server does not have a standard 2.5-inch drive tray, use a bracket or adapter which enables it to fit properly.\n\n2. Use an internal mini-SAS HD to SATA cable, as required, to attach the SSD(s) to the controller, as shown in the example below.\n\n3. When all SSDs have been installed and connected, close your computer cabinet, reattach the power cord, then continue with Connecting External Devices on page 34.\n\n**Connecting External Devices**\n\n**Note:** If you are not connecting any external devices, see the following section, Next Steps on page 35.\nUse high-quality cables to connect your controller to your external device(s), such as disk drives or disk drive enclosures. We recommend using only Adaptec cables. For more information about cabling options for your controller, see Cables on page 25.\n\n**Next Steps**\n\nIf you are installing the controller driver and an operating system onto a bootable array, continue with Creating a Bootable Array on page 36.\n\nIf you are completing a standard installation onto an existing operating system, continue with Installing the Driver on an Existing Operating System on page 52.\n6 Creating a Bootable Array\n\nThis chapter explains how to set your Adaptec controller to be the boot controller, and how to create a bootable array.\n\n**Note:** If you are completing a standard installation onto an existing operating system, you don’t have to complete this task. Skip to *Installing the Driver on an Existing Operating System* on page 52.\n\n**Setting the Boot Controller**\n\n**Note:** If your system won’t contain more than one bootable controller, skip to the next section, *Creating an Array* on page 36.\n\nYour Adaptec RAID controller supports bootable disk drives and bootable arrays. To enable your system to boot from either a disk drive or an array connected to your controller:\n\n1. Enter the system setup.\n2. Navigate to the drive boot sequence.\n3. Move the boot controller to the top of the list.\n\nFor more information, refer to your computer documentation.\n\n**Creating an Array**\n\nThis section explains how to create an array.\n\nA RAID 5 array is created in the examples shown in this section because RAID 5 provides the most security and best performance with a minimum of three disk drives. However, you can choose to create an array with a different RAID level; you can also change array level later, after the operating system is installed.\n\nYou can create an array using any of these tools:\n\n- Adaptec RAID Configuration Utility (ARC)—BIOS-based menus and keyboard navigation (see the following section).\n- maxView Storage Manager—Graphical software application (running from a bootable installation DVD) that you can navigate with your mouse (see *About maxView Storage Manager* on page 57).\n- ARCCONF—Command line utility. For instructions, refer to the *Adaptec RAID Controller Command Line Utility User’s Guide*.\n\nYou can use any of these tools, but the ARC utility is the quickest and easiest tool for this task.\n\n**Note:** We recommend that you do not combine SAS and SATA disk drives within the same array. maxView Storage Manager displays a warning if you try to create a logical drive using a combination of SAS and SATA disk drives. See *What is SAS?* on page 62 for more information.\n\n**Creating an Array with the ARC Utility**\n\nThe ARC utility is menu-based. Instructions for completing tasks appear on-screen. Menus can be navigated using the arrows, Enter, Esc, and other keys on your keyboard.\n\nTo create a RAID 5 array:\n\n1. Power on your computer. When prompted, press Ctrl+A to enter the ARC utility.\n\n **Note:** On servers that support the Unified Extensible Firmware Interface, or uEFI, ARC utility options are presented with a uEFI/HII interface rather than the Adaptec Ctrl-A interface described below. To begin using the ARC utility with the uEFI/HII interface, see *Ctrl-A or uEFI/HII?* on page 74.\n\n2. If you have more than one controller of the same model or family in your computer, select your controller, then press Enter.\n3. Select **Logical Device Configuration**, then press **Enter**.\n\n4. Select **Initialize Drives**, then press **Enter**.\n\n5. Select at least three disk drives for the array, press **Insert** for each selected disk drive, then press **Enter**.\n \n **Caution:** During initialization, all data is deleted from the disk. Before continuing, back up any data you want to keep.\n\n6. Press **Y**, then press **Enter**.\n The selected disk drives are initialized, then the Logical Device Configuration screen appears.\n\n7. Select **Create Array**, then press **Enter**.\n\n8. Select the disk drives that were just initialized, press **Insert** for each selected disk drive, then press **Enter**.\n\n9. When the Array Properties screen opens, follow the instructions in the following table.\n\n<table>\n<thead>\n<tr>\n<th>Property Line</th>\n<th>Entry or Selection</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Array Type</td>\n<td>Select <strong>RAID 5</strong>, then press <strong>Enter</strong>.</td>\n</tr>\n<tr>\n<td>Array Label</td>\n<td>Type a name, then press <strong>Enter</strong>.</td>\n</tr>\n<tr>\n<td>Array Size</td>\n<td>Press <strong>Enter</strong>, then press <strong>Enter</strong> again to use the default granularity of GB.</td>\n</tr>\n<tr>\n<td>Stripe Size</td>\n<td>Press <strong>Enter</strong> to use the default (256 KB).</td>\n</tr>\n<tr>\n<td>Read Caching</td>\n<td>Press <strong>Enter</strong> to use the default (Enable).</td>\n</tr>\n<tr>\n<td>Write Caching</td>\n<td>Press <strong>Enter</strong> to use the default (Enable always), then press <strong>Y</strong> to confirm.</td>\n</tr>\n<tr>\n<td>Create RAID via</td>\n<td>Press <strong>Enter</strong> to use the default (Build/Verify).</td>\n</tr>\n<tr>\n<td>MaxCache Read</td>\n<td>Press <strong>Enter</strong> to use the default (Enable)</td>\n</tr>\n<tr>\n<td>MaxCache Write</td>\n<td>Press <strong>Enter</strong> to use the default (Disable)</td>\n</tr>\n<tr>\n<td>[Done]</td>\n<td>Press <strong>Enter</strong>.</td>\n</tr>\n</tbody>\n</table>\n\n10. When a cache warning message displays, type **Y**.\n\n11. Once the array is created, a message displays telling you that the array can now be used. Press any key to return to the Logical Device Configuration menu.\n You can start using the array immediately. However, performance is reduced until the build process is complete.\n\n12. Press **Esc** until the Exit utility window appears.\n\n13. Select **Yes**, then press **Enter**.\n The computer restarts.\n\n\n**Creating an Array with maxView Storage Manager**\n\nThis section describes how to use the maxView Storage Manager configuration wizard to build an array.\n\n**Note:** You will need the Adaptec Installation DVD to complete this task.\n\nTo create a RAID 5 array:\n\n1. Insert the Adaptec Installation DVD into your DVD drive, then restart your computer.\n\n2. When prompted, select the language you want, then press **Enter**.\n3. Review the license information, then press Enter.\n The DVD main menu opens.\n\n4. Click Launch Configuration Utility.\n maxView Storage Manager opens.\n\n5. On the ribbon, in the Logical Disk group, click Create Logical Drive.\n\n6. When the wizard opens, ensure that Express Configuration is selected, then click Next.\n\n7. Review the logical drive configuration summary.\n maxView Storage Manager uses the term logical drive when referring to an array (see Terminology Used in this Guide on page 14).\n The following example shows a RAID 5 array, ready to be created.\n8. Click Finish. maxView Storage Manager builds the logical drives.\n\n9. Partition and format your logical drive. The logical drives you created appear as a physical disk drives on your operating system. You must partition and format these logical drives before you can use them to store data.\n\n10. Close all windows, then click Reboot to restart your system.\n\n11. Remove the Adaptec Installation DVD. For information on installing and using maxView Storage Manager as a full software application, refer to the maxView Storage Manager User’s Guide.\n\n12. Continue with the following section.\n\n**Making Your Array Bootable**\n\nUse the ARC Utility to make the array bootable (see *Creating Bootable Arrays* on page 75). Then continue with *Installing the Driver and an Operating System* on page 40.\nInstalling the Driver and an Operating System\n\nThis chapter explains how to install your Adaptec RAID controller driver and an operating system on a bootable array (see Creating a Bootable Array on page 36).\n\nTo install the driver on an existing operating system, see Installing the Driver on an Existing Operating System on page 52.\n\nBefore You Begin\n\n- Install and connect your Adaptec RAID controller and internal disk drives (see Installing the Controller and Disk Drives on page 29).\n- Create a bootable array (see Creating a Bootable Array on page 36).\n- Create a driver disk (see the following section).\n\nNote: For up-to-date operating system version support, visit the Adaptec Web Site at www.adaptec.com. From the main menu select Support>Knowledgebase>Find Answers. Select your controller type and OS to generate a list of supported operating systems and to download the latest drivers.\n\nCreating a Driver Disk\n\nThis section describes how to create a driver disk for the operating systems that require one. You will need a USB flash drive or writable CD to complete this task.\n\n- Windows operating systems do not require a driver disk. For Windows, the driver is loaded directly from the Adaptec Installation DVD; see Installing with Windows on page 42.\n- For Debian Linux, Ubuntu Linux, and VMware ESX 4.1, you must create the driver disk manually on a USB flash drive (“USB stick”) or writable CD. See the instructions for your operating system, below.\n- For Red Hat 6 and Cent OS 6 DKMS driver installation, see Red Hat Linux 6, Cent OS 6 with Dynamic Kernel Module Support on page 42.\n- For VMware ESXi 5.x, see Installing with VMware ESXi 5.x on page 48.\n- For Citrix XenServer, see Installing with Citrix XenServer on page 51.\n- For all other OSs, create the driver disk using the Create Diskette menu on the Adaptec Installation DVD.\n\nTo create a driver disk using the Create Diskette menu:\n\n1. Set your system BIOS so that your computer boots from the DVD drive.\n2. Turn on your computer, then insert the Adaptec Installation DVD.\n3. Click Create Diskette, then select your operating system and version.\n4. When prompted, insert a USB flash drive, then click OK.\n The system creates the driver disk on the USB drive.\n5. Remove and label the driver disk.\n6. Continue with the instructions for your operating system:\n - For Red Hat Linux 5 or Cent OS 5, see Installing with Red Hat Linux 5 or Cent OS 5 on page 42.\n - For Red Hat Linux 6, Cent OS 6, or Fedora Linux, see Red Hat Linux 6, Cent OS 6, Fedora Linux without Dynamic Kernel Module Support on page 43.\n - For SuSE Linux, see Installing with SuSE Linux Enterprise Server on page 44.\n - For Solaris, see Installing with Solaris on page 46.\n - For FreeBSD, see Installing with FreeBSD on page 47.\nCreating a Driver Disk for Debian Linux or Ubuntu Linux\n\nNote: You will need the Adaptec Installation DVD and a USB flash drive to complete this task.\n\nTo create a driver disk for Debian or Ubuntu Linux:\n\n1. Insert and mount the Adaptec Installation DVD:\n\n ```\n mount /dev/cdrom /mnt/cdrom\n ```\n\n2. Insert and mount a USB flash drive:\n\n ```\n mount /dev/sda1 /mnt/aacraid-driver\n ```\n\n3. Change to the Linux driver directory on the Adaptec Installation DVD, locate the .tgz archive file for your Debian or Ubuntu operating system version (32-bit or 64-bit), then extract the contents of the archive to a temporary location.\n\n4. Copy the contents of the archive to the USB drive by typing this command:\n\n ```\n cp /<tempdir>/* /mnt/aacraid-driver\n ```\n\n where `tempdir` is the temporary location of the driver files.\n\n5. Unmount and remove the Adaptec Installation DVD and USB drive.\n\n6. Continue with Installing with Debian Linux on page 44 or Installing with Ubuntu Linux on page 45.\n\nCreating a Driver Disk for VMware ESX 4.1\n\nNote: You will need the Adaptec Installation DVD and a writeable CD to complete this task.\n\nTo create a driver disk for VMware ESX 4.1:\n\n1. Insert and mount the Adaptec Installation DVD:\n\n ```\n mount /dev/cdrom /mnt/cdrom\n ```\n\n2. Insert and mount a writable CD:\n\n ```\n mount /dev/cdrom1 /mnt/cdrom1\n ```\n\n3. Change to the Linux driver directory on the Adaptec Installation DVD, locate the VMware iso image, `vmware-aacraid-400.4.2.1.xxxxx-esx4.1.iso` (where `xxxxx` is the build number), then burn the iso to the CD.\n\n Note: Use whatever tool you prefer to burn the CD, such as an interactive (GUI-based) tool or the Linux command line.\n\n4. Unmount and remove the Adaptec Installation DVD and CD drive.\n\n5. Continue with Installing with VMware ESX 4.1 on page 47.\nInstalling with Windows\n\n**Note:** The following instructions apply to all supported Windows operating systems. You will need your Windows Installation CD to complete this task.\n\nTo install the Adaptec RAID controller driver while installing Windows:\n\n1. Insert your Windows CD, then restart the computer.\n2. Follow the on-screen instructions to begin the Windows installation.\n3. When prompted to specify a location for Windows, select **Load Driver**.\n4. Insert the Adaptec Installation DVD, browse to the driver location, then click **OK**. The 64-Bit driver is located within the AMD64 folder.\n5. When the Adaptec driver is found, press **Next**. You may see the message ‘No drives were found’. Repeat **Step 3**, **Step 4**, and **Step 5**. On the second attempt, the driver will load successfully.\n6. Click **Next** again to accept the default partition configuration, or refer to your Windows documentation to configure partitions manually.\n7. Follow the on-screen instructions to complete the installation.\n8. Continue with **Managing Your Storage Space** on page 57.\n\nInstalling with Red Hat Linux 5 or Cent OS 5\n\n**Note:** You will need the installation CD for your operating system to complete this task.\n\nTo install the Adaptec RAID controller driver while installing Red Hat Linux 5 or Cent OS 5:\n\n1. Insert your installation CD.\n2. Restart your computer.\n3. When the first installation screen appears, insert the USB driver disk.\n4. Type this command at the Boot: prompt and press Enter:\n\n```\nlinux dd\n```\n5. Select **Yes** to indicate that you have a driver disk, then select the driver image from the USB drive (typically, `/dev/sda1`).\n6. Complete the Linux installation, following the on-screen instructions.\n7. Continue with **Managing Your Storage Space** on page 57.\n\nInstalling with Red Hat Linux 6, Cent OS 6, or Fedora Linux\n\nFollow the instructions in this section to install the controller driver with Red Hat Linux 6, Cent OS 6, or Fedora Linux. We recommend that you install the driver with **Dynamic Kernel Module Support**, or DKMS. DKMS ensures that the driver remains installed across OS or online updates. The DKMS instructions are valid for Red Hat 6 and Cent OS 6 only.\n\n**Red Hat Linux 6, Cent OS 6 with Dynamic Kernel Module Support**\n\n**Note:** You will need your OS installation CD and a USB flash drive to complete this task. You must have root privileges to install the driver image.\n\nTo install the Adaptec RAID controller driver while installing Red Hat 6 or Cent OS 6:\n\n1. Copy `aaccraid-1.2.1.29900-dd.img` and `aaccraid.conf` from the Linux driver directory on the Adaptec Installation DVD to a USB flash drive. Remove the USB drive when you are finished.\n2. Insert the OS installation CD, then restart your computer.\n3. When the graphical Welcome screen appears, press Tab, then insert the USB driver disk.\n4. Make sure that \"Install a new system or upgrade an existing system\" is highlighted, then, at the end of the \"vmlinuz initrd=initrd.img\" line press Space, type the following command, and press Enter:\n\n linux dd\n\n5. Select Yes to indicate that you have a driver disk, then select the driver image from the USB drive (typically, /dev/sda1).\n\n6. Complete the Linux installation, following the on-screen instructions, then reboot.\n\n7. Assuming the USB driver disk is /dev/sda1, type the following commands to ensure that the driver remains installed when you update the OS:\n\n mount /dev/sda1 /mnt\n cp /mnt/aacraid.conf /etc/depmod.d/aacraid.conf\n\n8. Continue with Managing Your Storage Space on page 57.\n\nRed Hat Linux 6, Cent OS 6, Fedora Linux without Dynamic Kernel Module Support\n\nNote: You will need the Installation CD for your operating system to complete this task. You must have root privileges to install the driver image.\n\nTo install the Adaptec RAID controller driver while installing Red Hat 6, Cent OS 6, or Fedora Linux:\n\n1. Insert your installation CD.\n\n2. Restart your computer.\n\n3. When the Welcome screen appears, press Enter at the boot prompt, type CTRL+ALT+F2 to switch to the shell, then continue the installation by selecting your language and keyboard.\n\n4. Insert the USB driver disk.\n\n5. Assuming the USB drive is assigned to /dev/sda1, type the following commands to load the controller driver:\n\n mkdir /mnt2 /AACRAID\n mount /dev/sda1 /mnt2\n cp -r /mnt2/* /AACRAID\n umount /mnt2\n cd /AACRAID\n sh ./fc-pre-install.sh\n\n6. Press ALT+F6 to switch back to the installation screen, then click Next.\n\n7. Follow the on-screen prompts to continue the installation. When prompted to reboot the system, press CTRL+ALT+F2 to switch to the console. Do not reboot before completing Step 8!\n\n8. Type the following commands to complete the driver installation:\n\n mkdir /mnt/sysimage/tmp/AACRAID\n cp -r /AACRAID/* /mnt/sysimage/tmp/AACRAID\n chroot /mnt/sysimage/\n cd /tmp/AACRAID\n sh ./fc-post-install.sh\n exit\n\n9. Press ALT+F6 to switch back to the installation screen, finish the installation, then reboot.\n\n10. Continue with Managing Your Storage Space on page 57.\nInstalling with SuSE Linux Enterprise Server\n\nTo install the Adaptec RAID controller driver while installing SuSE Linux:\n\n1. Insert the first SuSE Installation CD.\n2. Restart your computer.\n3. When the SuSE installation selection screen appears, choose the type of installation you want, press the F6 key, then select Yes to indicate that you have a driver disk. (If F6 is not shown on the screen, you may have an older version of SuSE; press the Alt key instead.)\n4. Insert the USB driver disk.\n5. Type this command on the 'Boot Options' line and press Enter:\n \n `linux dd`\n\n6. When prompted to \"Please choose the Driver Update medium,\" highlight the USB partition, then select OK.\n \n If the \"choose Driver Update medium\" screen is displayed again, assume that the driver was accepted and select Back.\n7. Follow the prompts to continue the installation.\n \n Note: For SuSE Linux 11, switch to the console by typing CTRL+ALT+F2 when the installation is between 50%-90% complete, type this command:\n\n `cp -a /update/install /mnt/tmp`\n\n ...then press CTRL+ALT+F7 to return to the installation screen and complete the installation as usual.\n8. Complete the installation, following the on-screen instructions.\n9. Continue with Managing Your Storage Space on page 57.\n\nInstalling with Debian Linux\n\nNote: You will need your Debian Installation CD to complete this task. You must have root privileges to install the driver image.\n\nTo install the Adaptec RAID controller driver while installing Debian Linux:\n\n1. Insert the Debian Installation CD, then restart your computer.\n2. When the Welcome screen appears, select Graphical Install. Continue the installation until you see the \"Configure Network\" screen, then type CTRL+ALT+F2 to switch to the console.\n3. Insert the USB driver disk, then type the following command to scan for the device:\n\n `fdisk -l`\n\n Assuming the USB drive is assigned to /dev/sda1, type the following commands to begin loading the driver:\n\n `mkdir /AACRAID`\n `mount /dev/sda1 /mnt`\n `cp -R /mnt/* /AACRAID`\n `umount /mnt`\n \n Note: The following steps assume you are installing Debian 6 using kernel 2.6.32-5.\n\n5. Copy the driver file to the /lib/modules directory:\n\n Debian 32-bit:\ncp -f /AACRAID/aacraid.ko-PRE_MOD \n/lib/modules/2.6.32-5-486/kernel/drivers/scsi/aacraid/aacraid.ko\n\nDebian 64-bit:\n\ncp -f /AACRAID/aacraid.ko \n/lib/modules/2.6.32-5-amd64/kernel/drivers/scsi/aacraid/aacraid.ko\n\n6. Remove the USB drive.\n7. Install the loadable module:\n Debian 32-bit:\n insmod /lib/modules/2.6.32-5-486/kernel/drivers/scsi/aacraid/aacraid.ko\n\n Debian 64-bit:\n insmod /lib/modules/2.6.32-5-amd64/kernel/drivers/scsi/aacraid/aacraid.ko\n\n8. Press CTRL+ALT+F5 to switch back to the installation screen, then follow the on-screen prompts to continue the installation.\n Note: Do not press Continue at the end of the installation until you complete Step 9!\n\n9. When prompted to reboot the system, press CTRL+ALT+F2 to switch to the console.\n10. Type the following commands to complete the driver installation:\n Debian 32-bit:\n cp -f /AACRAID/aacraid.ko-POST_MOD \n /target/lib/modules/2.6.32-5-486/kernel/drivers/scsi/aacraid/aacraid.ko\n chroot /target\n /sbin/depmod -a 2.6.32-5-486\n update-initramfs -u -v\n exit\n\n Debian 64-bit:\n cp -f /AACRAID/aacraid.ko \n /target/lib/modules/2.6.32-5-amd64/kernel/drivers/scsi/aacraid/aacraid.ko\n chroot /target\n /sbin/depmod -a 2.6.32-5-amd64\n update-initramfs -u -v\n exit\n\n11. Press CTRL+ALT+F5 to switch back to the installation screen, then reboot.\n12. Continue with Managing Your Storage Space on page 57.\n\n**Installing with Ubuntu Linux**\n\n **Note**: You will need your Ubuntu Installation CD to complete this task. You must have root privileges to install the driver image.\n\nTo install the Adaptec RAID controller driver while installing Ubuntu Linux:\n\n1. Insert the Ubuntu Installation CD, then restart your computer.\n2. When the installation menu appears, select **Install Ubuntu Server**. Continue the installation until the \"Configure Network\" screen appears, then type CTRL+ALT+F2 to switch to the console.\n3. Insert the USB driver disk, then type the following command to scan for the device:\n\n `fdisk -l`\n4. Assuming the USB drive is assigned to /dev/sda1, type the following commands to begin loading the driver:\n\n```bash\nmkdir /AACRAID\nmount /dev/sda1 /mnt\ncp -R /mnt/* /AACRAID\numount /mnt\n```\n\n**Note:** The following steps assume you are installing Ubuntu 10 or 11, using kernel 2.6.32-28. For Ubuntu 12 or higher, the driver files aacraid.ko-PRE_MOD and aacraid.ko-POST_MOD are both replaced by the single file aacraid.ko.\n\n5. Copy the driver file to the /lib/modules directory:\n\n```bash\ncp -f /AACRAID/aacraid.ko-PRE_MOD /lib/modules/2.6.32-28-generic/kernel/drivers/scsi/aacraid/aacraid.ko\n```\n\n6. Remove the USB drive.\n\n7. Install the loadable module:\n\n```bash\ninsmod /lib/modules/2.6.32-28-generic/kernel/drivers/scsi/aacraid/aacraid.ko\n```\n\n8. Press CTRL+ALT+F1 to switch back to the installation screen, then follow the on-screen prompts to continue the installation.\n\n **Note:** Do not press Continue at the end of the installation until you complete Step 9!\n\n9. When prompted to reboot the system, press CTRL+ALT+F2 to switch to the console.\n\n10. Type the following commands to complete the driver installation:\n\n - Ubuntu 32-bit:\n ```bash\ncroot /target\n/sbin/depmod --a 2.6.32–28-generic-pae\nupdate-initramfs -u -v\nexit\n```\n\n - Ubuntu 64-bit:\n ```bash\ncroot /target /sbin/depmod --a 2.6.32–28-server\nupdate-initramfs -u -v\nexit\n```\n\n11. Press CTRL+ALT+F1 to switch back to the installation screen, then reboot.\n\n12. Continue with *Managing Your Storage Space* on page 57.\n\n### Installing with Solaris\n\n**Note:** This task is not necessary if you are installing Solaris 10 Update 2 or later. Instead, you can choose to install Solaris using the in-box driver and update it either during or after the installation is complete, if required.\n\n**Note:** If necessary, you can create a driver disk by burning a CD with the aac_solaris-x86.iso file, available on the Adaptec Installation DVD.\n\nTo install the Adaptec RAID controller driver while installing Solaris:\n\n1. Start your computer.\n2. Interrupt the autoboot, press the **ESC** key. The Device Configuration Assistant (DCA) Utility will open.\n3. Select **Apply driver updates**.\n4. Insert the driver disk or other update media, then press **Return**.\n5. Complete the Solaris installation, following the instructions included with your operating system.\n\n### Installing with FreeBSD\n\n**Note:** You will need your FreeBSD Installation CD to complete this task.\n\nTo install the Adaptec RAID controller driver while installing FreeBSD:\n\n1. Insert the FreeBSD Installation CD.\n2. Insert the USB driver disk.\n3. Restart your computer. (Be sure to boot from the installation CD!)\n4. When the FreeBSD start screen opens, select 2 for ‘Escape to Loader Prompt’.\n5. Type: `load kernel`\n6. Type this command to locate the USB drive: `lsdev`\n7. Assuming the USB drive is `disk2s1`, type this command:\n ```\n load disk2s1:aacu.ko\n ```\n8. Type this command: `boot`\n9. Complete the FreeBSD installation, as usual. When finished, remove the installation CD, but not the USB driver disk, then reboot.\n **Note:** Be sure the system is configured to boot from the controller's bootable array, not the USB drive!\n\n10. To ensure that the driver is loaded automatically as a module at boot time, repeat Steps 4-7, then complete the steps below.\n11. Type this command to boot to the kernel: `boot`\n12. Login as root, then type:\n ```\n dmesg\n ```\n13. Assuming the USB drive is `da1s1`, type this command to mount the drive:\n ```\n mount -t msdosfs /dev/da1s1 /mnt\n ```\n14. Install the driver package:\n ```\n pkg_add /mnt/aac9x-amd64.tgz\n ```\n **Note:** The distribution also includes driver packages for FreeBSD 8.\n15. Reboot the computer.\n\n### Installing with VMware ESX 4.1\n\n**Note:** You will need your VMware Installation CD to complete this task. You must have root privileges to create and install the driver image.\n\nTo install the Adaptec RAID controller driver while installing VMware ESX 4.1:\n\n1. Insert the VMware Installation CD.\n2. Restart your computer.\n3. Follow the on-screen instructions to begin the VMware installation.\n4. Select **Yes** to install a custom driver, then click **Add**.\n5. Insert the CD containing the driver, then click OK.\n\n6. Select the driver from the displayed list, click OK, then follow the on-screen instructions to load the driver.\n\n7. Complete the VMware installation, following the on-screen instructions.\n\n8. Reboot your computer, then remove the VMware Installation CD.\n\n **Note:** You may see a warning that the controller driver is not certified by VMware (no signature attached). You can ignore this message.\n\n### Installing with VMware ESXi 5.x\n\n**Note:** You will need a writable CD to complete this task. You must have administrator privileges to create the driver disk and install the driver image.\n\nTo install the Adaptec RAID controller driver with VMware ESXi 5.x, you must create a custom boot image using the VMware Image Builder tool. The VMware Image Builder is distributed as a snap-in component for vSphere PowerCLI, a command-line and scripting tool from VMware based on Microsoft PowerShell.\n\nYou can download PowerCLI from the VMware Download Center at [www.vmware.com/downloads](http://www.vmware.com/downloads). To perform the installation, you will also need to download the VMware ESXi5.x Standard Software Depot from the VMware Download Center.\n\n **Note:** In the following instructions, perform Steps 1-7 on the Windows machine used to build the custom boot image, and Steps 8-11 on the machine where you want to install the custom image. Be sure to install the prerequisite software first, including Powershell and Microsoft .NET 2.0, before you install PowerCLI or create the custom boot image.\n\nTo install the Adaptec RAID controller driver while installing VMware ESXi 5.x:\n\n1. Download Microsoft PowerShell and Microsoft .NET 2.0 (if not installed on your machine already) and install on your Windows build machine. You can download PowerShell and Microsoft .NET from the Microsoft Download Center at [www.microsoft.com/download](http://www.microsoft.com/download).\n\n **Note:** PowerShell is preinstalled on many Windows systems, including Windows Server 2012, Windows 7, and Windows 8.\n\n2. Download and install vSphere PowerCLI on your Windows build machine. You can download PowerCLI from the VMware Download Center at [www.vmware.com/downloads](http://www.vmware.com/downloads) (for example, VMware-PowerCLI-5.0.0-374833.exe).\n\n3. Run PowerShell as Administrator, then set the execution policy to Remote Signed:\n\n ```powershell\n # Set-ExecutionPolicy RemoteSigned\n ```\n\n4. Download the VMware ESXi5.x Standard Software Depot (for example, vmware-ESXi-5.0.0-469512-depot.zip or vmware-ESXi-5.1.0-799733-depot.zip) and store in a temporary location on your Windows build machine. You can download the software depot from the VMware Download Center at [www.vmware.com/downloads](http://www.vmware.com/downloads). When you start the download, be sure to choose \"ESXi Offline Bundle\".\n\n **Note:** You may need to provide account credentials to download the software depot from the VMware Web site.\n\n5. Insert the Adaptec Installation DVD, navigate to the Linux driver folder, then copy the Adaptec AACRAID driver binary to a temporary location on the Windows build machine:\n\n<table>\n<thead>\n<tr>\n<th>Options</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ESXi 5.0</td>\n<td>aacraid-esxi5.0-1.2.1.xxxxx.zip</td>\n</tr>\n<tr>\n<td>ESXi 5.1</td>\n<td>aacraid-esxi5.1-1.2.1.xxxxx.zip</td>\n</tr>\n</tbody>\n</table>\n\n where xxxxx is the build number.\nAfter you copy the file, remove the Adaptec Installation DVD.\n\n6. Launch vSphere PowerCLI, then follow the steps below to create the custom boot image:\n a) At the PowerCLI prompt, add the VMware Image Builder snap-in by running the following cmdlet:\n\n ```powershell\n # Add-PSSnapIn VMware.ImageBuilder\n \n Note: You will see a message if the Image Builder snap-in is already installed. You can ignore this message.\n \n Note: Continue using PowerCLI in Steps 6.b through 6.j.\n ```\n\n b) Add the VMware ESXi 5.x Software Depots:\n\n VMware ESXi 5.0:\n\n ```powershell\n # Add-EsxSoftwareDepot\n C:\\ESXi5.0-PMC-CustomISO\\vmware-ESXi-5.0.0-469512-depot.zip\n ```\n\n VMware ESXi 5.1:\n\n ```powershell\n # Add-EsxSoftwareDepot\n C:\\ESXi5.1-PMC-CustomISO\\vmware-ESXi-5.1.0-799733-depot.zip\n ```\n\n where C:\\ESXi5.x-PMC-CustomISO is the temporary folder on your build machine where the software depot is stored.\n\n c) Add the AACRAID driver binary as a software depot (where xxxxx is the build number):\n\n VMware ESXi 5.0:\n\n ```powershell\n # Add-EsxSoftwareDepot\n C:\\ESXi5.0-PMC-CustomISO\\aacraid-esxi5.0-1.2.1.xxxxx.zip\n ```\n\n VMware ESXi 5.1:\n\n ```powershell\n # Add-EsxSoftwareDepot\n C:\\ESXi5.1-PMC-CustomISO\\aacraid-esxi5.1-1.2.1.xxxxx.zip\n ```\n\n where C:\\ESXi5.x-PMC-CustomISO is the temporary folder on your build machine where the software depot is stored.\n\n d) Verify that the software depots are added:\n\n ```powershell\n # $DefaultSoftwareDepots\n ```\n\n e) List ESX Image Profiles:\n\n ```powershell\n # Get-EsxImageProfile\n You should see a display similar to this:\n \n ESXi-5.1.0-799733-no-tools\n ESXi-5.1.0-799733-standard\n ```\n\n f) Create a copy of the standard image profile, using the -CloneProfile option:\n\n VMware ESXi 5.0:\n\n ```powershell\n # New-EsxImageProfile -CloneProfile ESXi-5.0.0-469512-standard -Name \"ESXi 5.0 Adaptec Series 7\"\n ```\n\n VMware ESXi 5.1:\n\n ```powershell\n # New-EsxImageProfile -CloneProfile ESXi-5.1.0-799733-standard -Name \"ESXi 5.1 Adaptec Series 7\"\n ```\n\n g) Change the vendor and acceptance level of the new image profile:\nVMware ESXi 5.0:\n\n```\n# Set-EsxImageProfile -ImageProfile \"ESXi 5.0 Adaptec Series 7\" -vendor PMC-Sierra -AcceptanceLevel VMwareCertified\n```\n\nVMware ESXi 5.1:\n\n```\n# Set-EsxImageProfile -ImageProfile \"ESXi 5.1 Adaptec Series 7\" -vendor PMC-Sierra -AcceptanceLevel VMwareCertified\n```\n\nh) Check if the new driver package is available:\n\n```\n# Get-EsxSoftwarePackage\n```\n\nYou should see a line like this:\n\n```\nscsi-aacraid 5.1.5.2.1.29900-1 Adaptec_Inc 7/24/201...\n```\n\ni) Add the scsi-aacraid software package to the new image profile:\n\nVMware ESXi 5.0:\n\n```\n# Add-EsxSoftwarePackage -ImageProfile \"ESXi 5.0 Adaptec Series 7\" -SoftwarePackage scsi-aacraid\n```\n\nVMware ESXi 5.1:\n\n```\n# Add-EsxSoftwarePackage -ImageProfile \"ESXi 5.1 Adaptec Series 7\" -SoftwarePackage scsi-aacraid\n```\n\nj) Export the custom ISO image:\n\nVMware ESXi 5.0:\n\n```\n# Export-EsxImageProfile -ImageProfile \"ESXi 5.0 Adaptec Series 7\" -FilePath C:\\ESXi5.0-PMC-CustomISO\\ESXi5.0-PMC-Sierra-Series-7.iso -NoSignatureCheck -ExportToISO\n```\n\nVMware ESXi 5.1:\n\n```\n# Export-EsxImageProfile -ImageProfile \"ESXi 5.1 Adaptec Series 7\" -FilePath C:\\ESXi5.1-PMC-CustomISO\\ESXi5.1-PMC-Sierra-Series-7.iso -NoSignatureCheck -ExportToISO\n```\n\nwhere -FilePath specifies the path to the custom iso image.\n\n7. Burn the custom ISO image to a writable CD.\n\n **Note:** Use whatever tool you prefer to burn the CD, such as an interactive (GUI-based) tool or a command line tool.\n\n Remove the CD after you finish burning the image.\n\n8. On the VMware ESXi machine, insert the custom boot CD, then restart your computer.\n\n9. Follow the on-screen instructions to begin the VMware installation.\n\n10. Complete the VMware installation, following the on-screen instructions.\n\n11. Remove the custom boot CD, then reboot your computer.\nInstalling with Citrix XenServer\n\n**Note:** You will need the Adaptec Installation DVD, your XenServer installation CD, and a writable CD to complete this task. You must have administrator privileges to install the driver image.\n\nTo install the Adaptec RAID controller driver with Citrix XenServer, you must copy the XenServer driver iso image from the installation DVD, and burn it to a writeable CD. You will be prompted to insert the XenServer driver CD twice.\n\nTo install the Adaptec RAID controller driver while installing Citrix XenServer:\n\n1. On a Windows machine, insert the Adaptec Installation DVD, navigate to the Linux driver folder, then copy the XenServer driver iso image to a temporary location:\n\n<table>\n<thead>\n<tr>\n<th>Options</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>XenServer 6.1</td>\n<td>citrix-aacraid-1.2.1-xxxxx.xen-6.1.iso</td>\n</tr>\n</tbody>\n</table>\n\n where xxxxx is the build number.\n\n After you copy the file, remove the Adaptec Installation DVD.\n\n2. Burn the XenServer driver iso image to a writable CD.\n\n **Note:** Use whatever tool you prefer to burn the CD, such as an interactive, GUI-based, tool or a command line tool.\n\n Remove the CD after you finish burning the image.\n\n3. On the machine where you want to install the OS and RAID controller driver, insert the XenServer installation CD, then restart your computer.\n\n\n5. Remove the XenServer installation CD and insert the driver CD.\n\n6. When the driver update is complete, remove the driver CD and insert the XenServer installation CD.\n\n7. Continue the XenServer installation, following the on-screen instructions.\n\n8. When prompted to add a driver (at the end of the OS installation), remove the XenServer installation CD and insert the driver CD.\n\n9. Complete the XenServer installation, following the on-screen instructions.\n\n10. Remove the driver CD, then reboot your computer.\nInstalling the Driver on an Existing Operating System\n\nThis chapter explains how to install your Adaptec RAID controller driver on an existing operating system.\n\nNote: To install the driver while you’re installing an operating system, see Installing the Driver and an Operating System on page 40.\n\nBefore You Begin\n\nBefore you begin, install and connect your Adaptec RAID controller and internal disk drives (see Installing the Controller and Disk Drives on page 29).\n\nYou must also create a driver disk before you begin installing the controller driver.\n\nNote: For up-to-date operating system version support, visit the Adaptec Web Site at www.adaptec.com. From the main menu select Support>Knowledgebase>Find Answers. Select your controller type and OS support to generate a list of supported operating systems and to download the latest drivers.\n\nCreating a Driver Disk\n\nThis section describes how to create a driver disk for operating systems that require one. You will need a USB flash drive to complete this task.\n\n- Windows operating systems do not require a driver disk; see Installing on Windows on page 52.\n- For Debian Linux, the driver is loaded directly from the OS installation DVD; see Installing on Debian Linux on page 53.\n- For FreeBSD, VMware, and Citrix XenServer, you must copy the driver from the installation DVD and install it from the local system; see Installing on FreeBSD on page 54, Installing on VMware on page 55, and Installing on Citrix XenServer on page 56.\n- For all other OSs, create the driver disk using the Create Diskette menu on the Adaptec Installation DVD.\n\nTo create a driver disk using the Create Diskette menu:\n\n1. Set your system BIOS so that your computer boots from the DVD drive.\n2. Turn on your computer, then insert the Adaptec Installation DVD.\n3. Click Create Diskette, then select your operating system and version.\n4. When prompted, insert a USB flash drive, then click OK. The system creates the driver disk on the USB drive.\n5. Remove and label the driver disk.\n6. Continue with the instructions for your operating system:\n - For Red Hat, Cent OS, SuSE, or Fedora Linux, see Installing on Red Hat, Cent OS, SuSE, or Fedora Linux on page 53.\n - For Ubuntu Linux, see Installing on Ubuntu Linux on page 53.\n - For Solaris, see Installing on Solaris on page 54.\n\nInstalling on Windows\n\nNote: The following instructions apply to all supported Windows operating systems.\n\nTo install the driver on Windows:\n\n1. Start or restart Windows. The Found New Hardware Wizard opens and searches for the driver.\n2. Insert the driver disk, then select Locate and Install Driver Software.... and Don’t Search Online.\n3. Click Next, then click Close.\n4. When the installation is complete, remove the driver disk and restart your computer.\n5. Continue with *Managing Your Storage Space* on page 57.\n\n### Installing on Red Hat, Cent OS, SuSE, or Fedora Linux\n\nTo install the driver on Red Hat Linux, Cent OS, SuSE Linux, or Fedora Linux:\n\n1. Insert and mount the Adaptec Installation DVD:\n\n<table>\n<thead>\n<tr>\n<th>Options</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Red Hat, Cent OS</td>\n<td><code>mount /dev/cdrom /mnt/cdrom</code></td>\n</tr>\n<tr>\n<td>SuSE</td>\n<td><code>mount /dev/cdrom /media/cdrom</code></td>\n</tr>\n<tr>\n<td>Fedora</td>\n<td><code>mount /dev/hdc /mnt/cdrom</code></td>\n</tr>\n</tbody>\n</table>\n\n2. Install the module RPM:\n\n ```bash\n rpm -ivh mount-point/xxx/yyy.rpm\n ```\n\n where `mount-point` is the mount point on the Linux system, `xxx` is the driver path, and `yyy.rpm` is the rpm file.\n\n3. Reboot your computer to ensure the driver loaded correctly.\n\n4. Continue with *Managing Your Storage Space* on page 57.\n\n### Installing on Debian Linux\n\n**Note:** You must have root privileges to install the driver image. For Debian Linux, the `su` command is sufficient.\n\nTo install the driver on Debian Linux:\n\n1. Insert and mount the Debian Installation DVD:\n\n ```bash\n mount /dev/cdrom /mnt/cdrom\n ```\n\n2. Load the Debian unpacking tools:\n\n ```bash\n apt-get install build-essential\n ```\n\n3. Install the DEB driver package (where `xxxxx` is the build number):\n\n ```bash\n dpkg -i aacraid-1.2.1-xxxxx-Debian6.0-all.deb\n ```\n\n4. Reboot your computer to ensure the driver loaded correctly.\n\n5. Continue with *Managing Your Storage Space* on page 57.\n\n### Installing on Ubuntu Linux\n\n**Note:** For driver installation on Ubuntu Linux, you may need to create the root account and password. Enter these commands: `sudo bash; sudo passwd root`. You must have root privileges to install the driver image.\n\nTo install the driver on Ubuntu Linux:\n\n1. Update the Ubuntu package index:\n\n ```bash\n sudo apt-get update\n ```\n\n2. Load the Ubuntu unpacking tools:\n\n ```bash\n sudo apt-get install build-essential\n ```\n\n3. Install the DEB driver package (where `xxxxx` is the build number):\n\n ```bash\n dpkg -i aacraid-1.2.1-xxxxx-Debian6.0-all.deb\n ```\n\n Ubuntu 10.x:\nsudo dpkg -i aacraid-1.2.1-xxxxx-Debian+Ubuntu-all.deb\n\nUbuntu 11.x and Ubuntu 12.x:\nsudo dpkg -i aacraid-1.2.1-xxxxx-Ubuntu11.04+11.10+12.04-all.deb\n\n4. Reboot your computer to ensure the driver loaded correctly.\n5. Continue with *Managing Your Storage Space* on page 57.\n\n**Installing on Solaris**\n\nTo install the driver on Solaris:\n\n1. Start your computer.\n2. *(Solaris 10 only)* Check for any pre-existing Adaptec driver by running `pkginfo SUNWaac` in a terminal window. If there is no pre-existing Adaptec driver on your computer, continue with Step 3. If an Adaptec driver is already installed on your computer, run `pkgrm SUNWaac` to remove it.\n \n **Caution:** If your operating system currently boots from the Adaptec controller, do not reset your computer after you remove the pre-existing Adaptec driver. Instead, follow the steps in this section to install a new driver before rebooting your computer.\n\n3. Insert and mount the driver disk:\n\n `volcheck`\n\n4. Change to the driver installer directory:\n \n Solaris 10:\n \n `cd /rmdisk/aacraid/DU/sol_210/i86pc/Tools`\n\n Solaris 11:\n \n `cd /rmdisk/aacraid/DU/sol_211/i86pc/Tools`\n\n5. Start the driver installer:\n \n `./install.sh -i`\n\n6. Remove the driver disk, then reboot your computer.\n7. Continue with *Managing Your Storage Space* on page 57.\n\n**Installing on FreeBSD**\n\nTo install the driver on FreeBSD:\n\n1. Start your computer.\n2. Insert and mount the driver disk:\n\n `mount -t msdos /dev/fd1 /mnt`\n\n3. Copy the driver package to the /tmp directory:\n\n `cp /mnt/aac8x-i386.tgz /tmp`\n\n4. Install the driver package:\n\n `pkg_add /tmp/aac8x-i386.tgz`\n\n5. Remove the driver disk, then reboot your computer.\n6. Continue with *Managing Your Storage Space* on page 57.\nInstalling on VMware\n\nNote: You must remove the old driver before you can install the new one. You must have root privilege to install the new driver.\n\nNote: To copy the driver VIB file to the VMware ESX/ESXi server (in Step 2 below), you must have access to a remote copy utility, such as WinSCP, putty, or Linux scp.\n\nTo install the driver on VMware:\n\n1. At the VMware console screen, type these commands to remove the old driver:\n \n **VMware ESX 4.1:**\n \n ```\n esxupdate query --vib-view | grep -i aacraid (list driver packages)\n esxupdate -b <vibID> --maintenancemode remove (remove package)\n ```\n \n where `vibID` is the full name of the driver package.\n \n Note: For VMware 4.0 or earlier, use the `rpm -e` command to remove the driver.\n\n **VMware ESXi 5.x:**\n \n ```\n esxcli software vib list | grep -i aacraid (list driver packages)\n esxcli software vib remove --vibname=scsi-aacraid --maintenance-mode (remove package)\n ```\n\n2. Using a remote copy utility, copy the driver VIB file for your operating system version from the Linux driver folder on the installation DVD to a local directory on the ESX server. This example uses Linux scp to copy the driver to `/tmp/aacraid` (where `xxxxx` is the build number):\n \n **VMware ESX 4.1:**\n \n ```\n scp\n /mnt/cdrom/linux/driver/vmware-esx-drivers-scsi-aacraid-400.4.2.1.xxxxx-1.0.4.260247.x86_64.vib\n root@<esx-server-ip>:./tmp/aacraid\n ```\n\n **VMware ESXi 5.0:**\n \n ```\n scp\n /mnt/cdrom/linux/driver/vmware-esxi-drivers-scsi-aacraid-500.5.2.1.xxxxx-1.0.5.472560.x86_64.vib\n root@<esx-server-ip>:./tmp/aacraid\n ```\n\n **VMware ESXi 5.1:**\n \n ```\n scp\n /mnt/cdrom/linux/driver/vmware-esxi-drivers-scsi-aacraid-510.5.2.1.xxxxx-1.1.5.799733.x86_64.vib\n root@<esx-server-ip>:./tmp/aacraid\n ```\n \n Note: Due to file name limits on the installation DVD, the “_64.vib” portion of the file name may be truncated and not visible.\n\n3. Install the VIB module (where `xxxxx` is the build number):\n \n **VMware ESX 4.1:**\n \n ```\n esxupdate -b\n /tmp/aacraid/vmware-esx-drivers-scsi-aacraid-400.4.2.1.xxxxx-1.0.4.260247.x86_64.vib\n --nodeps --nosigcheck --maintenancemode update\n ```\n\n **VMware ESXi 5.0:**\n \n ```\n esxcli software vib install -f -v\n file:/tmp/aacraid/vmware-esxi-drivers-scsi-aacraid-500.5.2.1.xxxxx-1.0.5.472560.x86_64.vib\n ```\n\n **VMware ESXi 5.1:**\nesxcli software vib install -f -v\nfile:/tmp/aacraid/vmware-esxi-drivers-scsi-aacraid-510.5.2.1.xxxxx..-1.1.5.799733.x86_64.vib\n\n4. Reboot your computer.\n\n**Installing on Citrix XenServer**\n\n**Note:** To copy the driver RPM file to XenServer (in Step 1 below), you must have access to a remote copy utility, such as WinSCP, putty, or Linux scp. You must have root privilege to install the driver.\n\nTo install the driver on XenServer:\n\n1. Using a remote copy utility, copy the driver RPM file from the Linux driver folder on the Adaptec installation DVD to a local directory on XenServer. This example uses Linux scp to copy the driver to /tmp/aacraid (where xxxxx is the build number):\n\n ```\n scp /mnt/cdrom/linux/driver/citrix-aacraid-1.2.1-xxxxx.xen-6.1.rpm\n root@<xen-server-ip>:/tmp/aacraid\n ```\n\n2. Install the driver module rpm (where xxxxx is the build number):\n\n ```\n rpm -ivh /tmp/aacraid/citrix-aacraid-1.2.1-xxxxx.xen-6.1.rpm\n ```\n\n3. Reboot your computer.\nManaging Your Storage Space\n\nOnce you have installed your Adaptec RAID controller, disk drives (or other devices), and device driver, you can begin to build and manage your storage space. This chapter introduces maxView Storage Manager, and describes the other utilities included with your Adaptec RAID controller.\n\nAbout maxView Storage Manager\n\nmaxView Storage Manager is a browser-based software application that helps you build a storage space for your online data, using Adaptec RAID controllers and disk drives. With maxView Storage Manager, you can group disk drives into logical drives and build in redundancy to protect your data and improve system performance.\n\nFrom a single workstation, you can use maxView Storage Manager to monitor and manage all the controllers and disk drives in your storage space.\n\nWhen maxView Storage Manager is installed on a computer, the maxView Storage Manager Agent (and other related services) is also installed automatically. The Agent is designed to run in the background, without user intervention. Its job is to monitor system health, manage event notifications, task schedules, and other on-going processes on a system. It sends notices when tasks are completed successfully, and notifies you when errors or failures occur on that system.\n\nIf your storage space includes systems that won't be connected to monitors (and therefore won't require the graphical user interface), you can choose to run the Agent only on those systems instead of the full application. For more information, refer to the maxView Storage Manager User's Guide on the Adaptec Installation DVD.\n\nInstalling maxView Storage Manager\n\nmaxView Storage Manager is included on the Adaptec Installation DVD. For installation instructions, refer to the maxView Storage Manager User's Guide, in the books folder on the installation DVD.\n\nAbout the Adaptec RAID Controller Configuration Utility\n\nThe Adaptec RAID Controller Configuration (ARCCONF) is a command line utility that you can use to perform basic array and configuration management functions. With ARCCONF, you can:\n\n- Create and delete logical drives\n- Modify and copy configuration settings\n- Recover from disk drive failures and troubleshoot your system\n\nARCCONF is described in the Adaptec RAID Controller Command Line Utility User's Guide, which is included on the Adaptec Installation DVD.\n\nAbout the Adaptec RAID Configuration Utility\n\nThe Adaptec RAID Configuration (ARC) utility is a BIOS-based utility that you can use to create and manage controllers, disk drives and other devices, and arrays. The ARC utility comprises these tools:\n\n- Logical Device Configuration—For creating and managing arrays, and initializing and rescanning disk drives.\n- Controller Settings—For modifying your controller and disk drive settings.\n- Disk Utilities—For formatting or verifying disk drives.\n\nThe ARC utility is included in your controller's BIOS. For more information, see Using the Adaptec RAID Configuration Utility on page 74.\nNote: The ARC utility is primarily intended for pre-operating system installation configuration.\n\nAbout the Adaptec Flash Utility\n\nThe Adaptec Flash Utility (AFU) is a text-based DOS utility that you can use to update, save, or verify your RAID controller's firmware.\n\nCaution: Although the AFU contains safeguards to prevent you from accidentally damaging your RAID controller's flash contents, it is still important to use the AFU carefully and correctly to avoid rendering your RAID controller inoperable. We recommend that only advanced users familiar with working in DOS use the AFU. You can also use maxView Storage Manager to update the controller firmware. See the maxView Storage Manager User’s Guide for more information.\n\nWhich Utility Should I Use?\n\nTo create a bootable array, we recommend that you use the BIOS-based ARC utility (See Using the Adaptec RAID Configuration Utility on page 74).\n\nFor subsequent storage management tasks on most supported operating systems, including VMware Guest OSs, we recommend that you install and use maxView Storage Manager (see About maxView Storage Manager on page 57). As a full-featured software application with a graphical user interface, it is the easiest to use and offers the widest range of management functions. For operating systems that do not support the maxView Storage Manager GUI, such as FreeBSD, use the ARCCONF command line utility to configure and manage arrays.\n10 Solving Problems\nThis chapter provides basic troubleshooting information and solutions for solving controller problems.\n\nTroubleshooting Checklist\nIf you encounter difficulties installing or using your Adaptec RAID controller, check these items first:\n- With your computer powered off, check the connections to each disk drive, power supply, LED connector, and so on. Try disconnecting and reconnecting disk drives from the Adaptec RAID controller.\n- Check that your Adaptec RAID controller is installed in a compatible PCIe expansion slot. To double-check the bus compatibility of your controller, see About Your RAID Controller on page 17.\n- Ensure that your Adaptec RAID controller is firmly seated and secured in the PCIe expansion slot.\n- If your Adaptec RAID controller is not detected during system boot, try installing it in a different compatible expansion slot. (See Installing the Controller on page 29 for instructions.)\n- Did the driver install correctly?\n- If you have external disk drives (or other devices), are they powered on?\n- Check the Readme on the installation DVD for compatibility issues and known problems.\n\nIf you are still unable to resolve a problem, you can find additional troubleshooting information and direction on the Adaptec Web site at www.adaptec.com or the Support Knowledgebase at ask.adaptec.com.\n\nMonitoring Disk Drives Status\nYou can use the 'blink' feature in maxView Storage Manager to monitor the status of your SAS and SATA disk drives. When you blink a specific disk drive or set of disk drives, the LED(s) on the selected disk drives flash.\n\nThis table describes the LED flash states:\n\n<table>\n<thead>\n<tr>\n<th>Controller Device State</th>\n<th>Slot State</th>\n<th>LED Flash State</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Failed</td>\n<td>Device is faulty</td>\n<td>On</td>\n</tr>\n<tr>\n<td>Rebuilding</td>\n<td>Device is rebuilding</td>\n<td>Slow flash</td>\n</tr>\n<tr>\n<td>Blink</td>\n<td>Identify the device</td>\n<td>Fast flash</td>\n</tr>\n<tr>\n<td>Other</td>\n<td>No error</td>\n<td>Off</td>\n</tr>\n</tbody>\n</table>\n\nFor more information about using maxView Storage Manager to monitor your disk drives, refer to the maxView Storage Manager User’s Guide or the online Help.\n\nSilencing the Alarm\nIf your Adaptec RAID controller includes an alarm, the alarm will sound when an error occurs. To silence the alarm, use maxView Storage Manager (see Managing Your Storage Space on page 57.) OR the ARC utility (see Modifying Your Controller’s Configuration on page 78.)\n\nRecovering from a Disk Drive Failure\nThis section explains how to recover when a disk drive or SSD fails:\n- If the array was protected by a hot spare, see Failed Disk Drive Protected by a Hot Spare on page 60.\n- If the array was not protected by a hot spare, see Failed Disk Drive Not Protected by a Hot Spare on page 60.\n- If there is a disk drive failure in more than one array simultaneously, see Failure in Multiple Arrays Simultaneously on page 60.\n- If it is a RAID 0 array, see Disk Drive Failure in a RAID 0 Array on page 60.\n- If multiple disk drives fail within the same array, see Multiple Failures in the Same Array on page 60.\n- If the drive is part of the maxCache Container, see Failed SSD in maxCache Container on page 61.\n\n**Note:** maxView Storage Manager uses the term logical drives or logical devices when referring to arrays (see Terminology Used in this Guide on page 14).\n\n**Failed Disk Drive Protected by a Hot Spare**\n\nWhen an array is protected by a hot spare, if a disk drive in that array fails the hot spare is automatically incorporated into the array and takes over for the failed drive.\n\nTo recover from the failure:\n\n1. Remove and replace the failed disk drive.\n2. **If copyback is not enabled**—In maxView Storage Manager, remove the ‘hot spare’ designation from the original hot spare (the disk drive that was built into the array). Then, designate a new hot spare to protect the arrays on that controller.\n\n **If copyback is enabled**—Data is automatically moved back to its original location once the controller detects that the failed drive has been replaced. No action is required.\n\n**Failed Disk Drive Not Protected by a Hot Spare**\n\nWhen an array is not protected by a hot spare, if a disk drive in that array fails, remove and replace the failed disk drive. The controller detects the new disk drive and begins to rebuild the array.\n\nIf the controller fails to rebuild the array, check that the cables, disk drives, and controllers are properly installed and connected. Make sure that the new disk drive is equal or greater in size than the failed disk drive. Then, if necessary, use maxView Storage Manager to rebuild the array. For instructions, refer to the maxView Storage Manager User’s Guide or online Help.\n\n**Failure in Multiple Arrays Simultaneously**\n\nIf there’s a disk drive failure in more than one array at the same time (one failure per array), and the arrays have hot spares protecting them, the controller rebuilds the arrays with these limitations:\n\n- A hot spare must be of equal or greater size than the failed disk drive it’s replacing.\n- Failed disk drives are replaced with hot spares in the order in which they failed. (The array that includes the disk drive that failed first is rebuilt first, assuming an appropriate hot spare is available—see bullet above.)\n\nIf there are more disk drive failures than hot spares, see Failed Disk Drive Not Protected by a Hot Spare on page 60.\n\nIf copyback is enabled, data is moved back to its original location once the controller detects that the failed drive has been replaced.\n\n**Disk Drive Failure in a RAID 0 Array**\n\nBecause RAID 0 volumes do not include redundancy, if a disk drive fails in a RAID 0 array, the data can’t be recovered.\n\nCorrect the cause of the failure or replace the failed disk drives. Then, restore your data (if available).\n\n**Multiple Failures in the Same Array**\n\nExcept in RAID 6 and RAID 60 arrays (see Understanding RAID on page 67), if more than one disk drive fails at the same time in the same array, the data normally can’t be recovered.\n\nYou may be able to recover the data by forcing the logical drive online or by recreating the logical drive without the initialization step. You can use the BIOS utility, ARC (see About the Adaptec RAID Configuration Utility on page 57), the command-line utility, ARCCONF, or maxView Storage Manager. For more information, refer to the Adaptec RAID Controller Command Line Interface User’s Guide and the maxView Storage Manager User’s Guide.\nNote: In some instances, RAID 10 and RAID 50 arrays may survive multiple disk drive failures, depending on which disk drives fail.\n\nFailed SSD in maxCache Container\n\nBecause the maxCache Container is a redundant logical device, comprised of SSDs only, it is rebuilt automatically when a failed SSD is replaced, just like an ordinary array. Once you identify the failed SSD, for example, by using maxView Storage Manager’s rapid fault isolation feature, replace it with a new one (see Connecting Solid State Drives (SSDs) on page 33). The controller detects the new SSD and begins rebuilding the maxCache Container.\n\nResetting the Controller\n\nYou may need to reset, or flash, your Adaptec RAID controller if it becomes inoperable or if a firmware upgrade is unsuccessful. Adaptec RAID controllers support a reset protocol called HDA mode flash. For information about HDA mode, see the Readme on the installation DVD or contact your support representative. To locate the flash jumper on your RAID controller board, see the illustrations in About Your RAID Controller on page 17.\nA Introduction to SAS\nThis section provides a basic overview of the main features of SAS, introduces some common SAS terms, and explains how SAS differs from parallel SCSI.\n\nNote: For technical articles and tutorials about SAS, refer to the SCSI Trade Association (STA™) Web site at www.scsita.org.\n\nTerminology Used in This Appendix\nFor convenience, SAS HBAs and SAS RAID controllers are referred to generically in this chapter as SAS cards. HBAs, RAID controllers, disk drives, and external disk drive enclosures are referred to as end devices and expanders are referred to as expander devices.\nFor convenience, this chapter refers to end devices and expander devices collectively as SAS devices.\n\nWhat is SAS?\nLegacy parallel SCSI is an interface that lets devices such as computers and disk drives communicate with each other. Parallel SCSI moves multiple bits of data in parallel (at the same time), using the SCSI command set.\nSAS is an evolution of parallel SCSI to a point-to-point serial interface. SAS also uses the SCSI command set, but moves multiple bits of data one at a time. SAS links end devices through direct-attach connections, or through expander devices.\nSAS cards can typically support up to 128 end devices and can communicate with both SAS and SATA devices. (You can add 128 end devices—or even more—with the use of SAS expanders. See SAS Expander Connections on page 65.)\n\nNote: Although you can use both SAS and SATA disk drives in the same SAS domain (see SAS Expander Connections on page 65), we recommend that you do not combine SAS and SATA disk drives within the same array or logical drive. The difference in performance between the two types of disk drives may adversely affect the performance of the array.\n\nData can move in both directions simultaneously across a SAS connection (called a link—see How Do SAS Devices Communicate? on page 62). Link speed is 300 MB/sec in half-duplex mode. Therefore, a SAS card with eight links has a bandwidth of 2400 MB/sec.\nAlthough they share the SCSI command set, SAS is conceptually different from parallel SCSI physically, and has its own types of connectors, cables, connection options, and terminology, as described in the rest of this chapter.\nTo compare SAS to parallel SCSI, see How is SAS Different from Parallel SCSI? on page 66.\n\nHow Do SAS Devices Communicate?\nSAS devices communicate with each other through links. A link is a physical connection between two phys.\nAs shown in the following figure, SAS devices contain ports (see What’s a SAS Port? on page 63), ports contain phys, and each phy contains one transmitter and one receiver—one transceiver. A phy can belong to one port only.\nWhat’s a Phy?\n\nPhys are part of the physical communication connection between SAS devices. Each phy contains a transceiver that sends data back and forth between SAS devices.\n\nWhen a connection is formed between two end devices, a link is established from a phy in one port to a phy in the other port. As shown in the figure above, a wide port can support multiple independent links simultaneously.\n\nPhys are internal, within SAS connectors (see What’s a SAS Connector? on page 64).\n\nSAS cables physically connect one or more phys on one SAS device to one or more phys on another SAS device.\n\nWhat’s a SAS Port?\n\nNote: Because the physical link between SAS devices is from phy to phy, rather than port to port, a “port” is more of a virtual concept, different from what is normally considered a port on other types of RAID controllers and storage devices.\n\nA port is one or more phys. A narrow port contains one phy. A wide port typically contains four phys.\n\nEach port has its own unique SAS address (see How are Disk Drives Identified in SAS? on page 64), and all the phys in a port share that same SAS address.\n\nSAS card port options vary. A SAS card with four phys could be configured with one wide port, with two wide ports that comprise two phys, or with four narrow ports each containing one phy. (A wide port with four phys is referred to as a 4-wide or 4x port.)\n\nWhat’s a SAS Address?\n\nEach SAS port is identified with a unique SAS address, which is shared by all phys on that port.\n\nFor example, a SAS disk drive might have two narrow ports. Each port has one unique SAS address. The single phy in each port uses its port’s SAS address.\n\nIn another example, a SAS device might have one 4-wide port. That port has one SAS address, which is shared by all four phys in the port.\n\nUnlike SCSI devices and SCSI IDs, SAS devices self-configure their SAS addresses. User intervention is not required to set SAS addresses, and SAS addresses cannot be modified.\nWhat's a SAS Connector?\n\nA SAS or mini-SAS connector is the physical plug or receptacle that you see on a SAS device. It's what you plug a SAS cable into, or the end of the SAS cable that's being plugged in. (See Cables on page 25.)\n\nA connector is what forms physical links between phys. Some SAS connectors can support multiple links. The number of links a SAS connector can support is referred to as its width. Narrow connectors support a single link; wide connectors supports more than 1 link.\n\nA single SAS device may have one or more connectors. A single SAS connector may help form links between more than two SAS devices. (For instance, as shown in the figure in Connecting Drives Directly to the Controller on page 33, the 4-wide internal SAS connector forms links with four independent disk drives.)\n\nWhat do SAS Cables Look Like?\n\nInternal standard SAS cables are narrower than internal parallel SCSI cables. The connectors vary in size depending on the number of links they support, from single link connectors to 4-wide (or larger) connectors. Internal fan-out cables let you attach four disk drives to a single 4-wide connector.\n\nMini-SAS connectors support both internal and external SAS connections. The mini-SAS connectors are smaller than the standard SAS internal and external connectors. Mini-SAS connectors support single and multilinks with the ability to scale to future speed needs.\n\nFor examples of some internal SAS/mini-SAS cables and an external SAS/mini-SAS cables, see Cables on page 25.\n\nHow are Disk Drives Identified in SAS?\n\nIn the BIOS and in the management utilities (see Identifying Disk Drives on page 81), disk drives are identified in the following formats:\n\n- CNX:DevY = Device Y is attached to Connector X (see Direct-attach Connections on page 64 for more information)\n- BoxX:SlotX = Enclosure X is attached to a disk drive in Slot X (see Backplane Connections on page 65 for more information)\n- ExpX:PhyX = Expander X is attached to Phy X (see SAS Expander Connections on page 65 for more information)\n\nwhere X is the count number.\n\nNote: Devices other than disk drives (CDROM, tape drives, etc...) are listed in order after your system disk drives.\n\nIn parallel SCSI, XX is the disk drive's channel number, YY is the target number, and ZZ is the logical unit number (LUN).\n\nWhat are the SAS Connection Options?\n\nYou can connect end devices to each other through direct cable connections and through backplane connections. When you use one or more expander devices (see SAS Expander Connections on page 65), you can create large configurations.\n\nDirect-attach Connections\n\nIn a direct-attach connection, SAS or SATA disk drives are connected directly to a SAS card with SAS or mini-SAS cables. One disk drive is attached to one SAS/mini-SAS connector with one SAS/mini-SAS cable (or multiple disk drives are attached to one SAS/mini-SAS connector with one fan-out cable). The figure in Connecting Drives Directly to the Controller on page 33 shows an example of direct-attach connections.\nThe number of direct-attached disk drives is limited to the number of *phys* supported by the SAS card. (Note that there may be multiple phys within a single connector. See *SAS Expander Connections* on page 65.)\n\n**Backplane Connections**\n\nIn a backplane connection, disk drives and SAS cards are attached to and communicate with each other through a system backplane.\n\nThere are two types of backplane connections, *passive* and *active*. When connecting to either backplane, it’s important to properly connect your disk drive LEDs in order to identify disk drive conditions. See *About Your RAID Controller* on page 17 for your RAID controller Activity LED connections and locations.\n\nOnce you have connected to a backplane, use maxView Storage Manager to manage your disk drives. For more information, refer to the *maxView Storage Manager User’s Guide* on the Adaptec Installation DVD.\n\nThe number of end devices is limited to the number of slots available on the backplane. For example, the Adaptec S50 enclosure, which contains an expander, is a backplane connection that supports up to 12 SAS or SATA disk drives.\n\nSome backplanes support daisy-chain expansion to other backplanes. For example, you can daisy-chain (connect one to the next) up to nine Adaptec S50 enclosures to a single SAS card in a host system.\n\n**SAS Expander Connections**\n\nA SAS expander device literally expands the number of end devices that you can connect together. Expander devices, typically embedded into a system backplane (see *Backplane Connections* on page 65), support large configurations of SAS end devices, including SAS cards and SAS and SATA disk drives.\n\nWith expander devices, you can build large and complex storage topologies.\n\nThere are two types of SAS expanders: *fanout expanders* and *edge expanders*. Each performs a different role in a storage system. (For more information about how SAS expanders work, refer to the STA Web site at www.scsita.org.)\n\nYou can connect up to 128 SAS ports to an edge expander. (A single edge expander can therefore support up to 128 SAS addresses.)\n\nYou can connect up to 128 edge expanders to a fanout expander.\n\nYou can use only one fanout expander in any single SAS *domain* (a topology of SAS—and possibly SATA—end devices and expander devices). A single SAS domain can therefore comprise up to 16,384 SAS ports (and therefore up to 16,384 SAS addresses including the fanout expander).\n\nThe next figure illustrates (in very basic terms) a SAS domain and shows how SAS cards, SAS and SATA disk drives, and expander devices can fit together in a large data storage topology.\nHow is SAS Different from Parallel SCSI?\n\nIn summary, although SAS and parallel SCSI both use the SCSI command set, how they move data from one place to another is very different. To support point-to-point serial data transport, SAS introduces new types of connectors, cables, connection options, and terminology.\n\nGenerally speaking, SAS is faster and more flexible than parallel SCSI, and provides more options for building your storage space. SAS lets you mix SAS and SATA disk drives together, and lets you connect many, many more devices.\n\nThis table describes many of the main differences between the two interfaces.\n\n<table>\n<thead>\n<tr>\n<th>Parallel SCSI</th>\n<th>Serial Attached SCSI</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Parallel interface</td>\n<td>Serial interface</td>\n</tr>\n<tr>\n<td>Maximum speed 320 MB/sec shared by all devices on the bus</td>\n<td>Maximum speed 300 MB/sec per phy when in half-duplex mode</td>\n</tr>\n<tr>\n<td>Supports SCSI devices only</td>\n<td>Supports SATA and SAS disk drives simultaneously</td>\n</tr>\n<tr>\n<td>Up to 16 devices per SCSI channel</td>\n<td>More than 100 disk drives per SAS card, using an expander (see SAS Expander Connections on page 65) or 50 SATAII disk drives.</td>\n</tr>\n<tr>\n<td>Supports single-port devices only</td>\n<td>Supports single- and dual-port devices</td>\n</tr>\n<tr>\n<td>Uses SCSI IDs to differentiate between devices connected to the same adapter</td>\n<td>Uses unique SAS addresses to differentiate between devices</td>\n</tr>\n<tr>\n<td>User intervention required to set SCSI IDs</td>\n<td>SAS addresses self-configured by SAS devices</td>\n</tr>\n<tr>\n<td>Requires bus termination</td>\n<td>Requires no bus termination</td>\n</tr>\n<tr>\n<td>Standard SCSI connectors</td>\n<td>SAS connectors (see Cables on page 25)</td>\n</tr>\n</tbody>\n</table>\nUnderstanding RAID\n\nWhen you create arrays (or logical drives), you can assign a RAID level to protect your data. Each RAID level offers a unique combination of performance and redundancy. RAID levels also vary by the number of disk drives they support.\n\nThis appendix describes the RAID levels supported by your Adaptec RAID controller, and provides a basic overview of each to help you select the best level of protection for your data storage.\n\nUnderstanding Drive Segments\n\nA drive segment is a disk drive or portion of a disk drive that is used to create an array. A disk drive can include both RAID segments (segments that are part of an array) and available segments. Each segment can be part of only one logical device at a time. If a disk drive is not part of any logical device, the entire disk is an available segment.\n\nNon-redundant Arrays (RAID 0)\n\nAn array with RAID 0 includes two or more disk drives and provides data striping, where data is distributed evenly across the disk drives in equal-sized sections. However, RAID 0 arrays do not maintain redundant data, so they offer no data protection.\n\nCompared to an equal-sized group of independent disks, a RAID 0 array provides improved I/O performance.\n\nDrive segment size is limited to the size of the smallest disk drive in the array. For instance, an array with two 250 GB disk drives and two 400 GB disk drives can create a RAID 0 drive segment of 250 GB, for a total of 1000 GB for the volume, as shown in this figure.\n\n![Diagram showing RAID 0 configuration with disk drives and segment sizes.]\n**RAID 1 Arrays**\n\nA RAID 1 array is built from two disk drives, where one disk drive is a mirror of the other (the same data is stored on each disk drive). Compared to independent disk drives, RAID 1 arrays provide improved performance, with twice the read rate and an equal write rate of single disks. However, capacity is only 50 percent of independent disk drives.\n\nIf the RAID 1 array is built from different-sized disk drives, the free space, drive segment size is the size of the smaller disk drive, as shown in this figure.\n\n**RAID 1 Enhanced Arrays**\n\nA RAID 1 Enhanced (RAID 1E) array—also known as a striped mirror—is similar to a RAID 1 array except that data is both mirrored and striped, and more disk drives can be included. A RAID 1E array can be built from three or more disk drives.\n\nIn this example, the large bold numbers represent the striped data, and the smaller, non-bold numbers represent the mirrored data stripes.\n**RAID 10 Arrays**\n\nA RAID 10 array is built from two or more equal-sized RAID 1 arrays. Data in a RAID 10 array is both striped and mirrored. Mirroring provides data protection, and striping improves performance.\n\nDrive segment size is limited to the size of the smallest disk drive in the array. For instance, an array with two 250 GB disk drives and two 400 GB disk drives can create two mirrored drive segments of 250 GB, for a total of 500 GB for the array, as shown in this figure.\nRAID 5 Arrays\n\nA RAID 5 array is built from a minimum of three disk drives, and uses data striping and parity data to provide redundancy. Parity data provides data protection, and striping improves performance.\n\nParity data is an error-correcting redundancy that’s used to re-create data if a disk drive fails. In RAID 5 arrays, parity data (represented by Ps in the next figure) is striped evenly across the disk drives with the stored data.\n\nDrive segment size is limited to the size of the smallest disk drive in the array. For instance, an array with two 250 GB disk drives and two 400 GB disk drives can contain 750 GB of stored data and 250 GB of parity data, as shown in this figure.\nRAID 50 Arrays\n\nA RAID 50 array is built from six to forty-eight disk drives configured as two or more RAID 5 arrays, and stripes stored data and parity data across all disk drives in both RAID 5 arrays. (For more information, see RAID 5 Arrays on page 70.)\n\nThe parity data provides data protection, and striping improves performance. RAID 50 arrays also provide high data transfer speeds.\n\nDrive segment size is limited to the size of the smallest disk drive in the array. For example, three 250 GB disk drives and three 400 GB disk drives comprise two equal-sized RAID 5 arrays with 500 GB of stored data and 250 GB of parity data. The RAID 50 array can therefore contain 1000 GB (2 x 500 GB) of stored data and 500 GB of parity data.\n\nIn this figure, P represents the distributed parity data.\nRAID 6 Arrays\n\nA RAID 6 array—also known as dual drive failure protection—is similar to a RAID 5 array because it uses data striping and parity data to provide redundancy. However, RAID 6 arrays include two independent sets of parity data instead of one. Both sets of parity data are striped separately across all disk drives in the array.\n\nRAID 6 arrays provide extra protection for your data because they can recover from two simultaneous disk drive failures. However, the extra parity calculation slows performance (compared to RAID 5 arrays). RAID 6 arrays must be built from at least four disk drives. Maximum stripe size depends on the number of disk drives in the array.\n\nRAID 60 Arrays\n\nSimilar to a RAID 50 array (see RAID 50 Arrays on page 71), a RAID 60 array—also known as dual drive failure protection—is built from eight disk drives configured as two or more RAID 6 arrays, and stripes stored data and two sets of parity data across all disk drives in both RAID 6 arrays.\n\nTwo sets of parity data provide enhanced data protection, and striping improves performance. RAID 60 arrays also provide high data transfer speeds.\nComparing RAID Levels\n\nUse this table to select the RAID levels that are most appropriate for the logical drives on your storage space, based on the number of available disk drives and your requirements for performance and reliability.\n\n<table>\n<thead>\n<tr>\n<th>RAID Level</th>\n<th>Redundancy</th>\n<th>Disk Drive Usage</th>\n<th>Read Performance</th>\n<th>Write Performance</th>\n<th>Built-in Hot Spare</th>\n<th>Minimum Disk Drives</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RAID 0</td>\n<td>No</td>\n<td>100%</td>\n<td>***</td>\n<td>***</td>\n<td>No</td>\n<td>2</td>\n</tr>\n<tr>\n<td>RAID 1</td>\n<td>Yes</td>\n<td>50%</td>\n<td>**</td>\n<td>**</td>\n<td>No</td>\n<td>2</td>\n</tr>\n<tr>\n<td>RAID 1E</td>\n<td>Yes</td>\n<td>50%</td>\n<td>**</td>\n<td>**</td>\n<td>No</td>\n<td>3</td>\n</tr>\n<tr>\n<td>RAID 10</td>\n<td>Yes</td>\n<td>50%</td>\n<td>**</td>\n<td>**</td>\n<td>No</td>\n<td>4</td>\n</tr>\n<tr>\n<td>RAID 5</td>\n<td>Yes</td>\n<td>67 – 94%</td>\n<td>***</td>\n<td>*</td>\n<td>No</td>\n<td>3</td>\n</tr>\n<tr>\n<td>RAID 5EE</td>\n<td>Yes</td>\n<td>50 – 88%</td>\n<td>***</td>\n<td>*</td>\n<td>Yes</td>\n<td>4</td>\n</tr>\n<tr>\n<td>RAID 50</td>\n<td>Yes</td>\n<td>67 – 94%</td>\n<td>***</td>\n<td>*</td>\n<td>No</td>\n<td>6</td>\n</tr>\n<tr>\n<td>RAID 6</td>\n<td>Yes</td>\n<td>50 – 88%</td>\n<td>**</td>\n<td>*</td>\n<td>No</td>\n<td>4</td>\n</tr>\n<tr>\n<td>RAID 60</td>\n<td>Yes</td>\n<td>50 – 88%</td>\n<td>**</td>\n<td>*</td>\n<td>No</td>\n<td>8</td>\n</tr>\n</tbody>\n</table>\n\nDisk drive usage, read performance, and write performance depend on the number of drives in the logical drive. In general, the more drives, the better the performance.\nUsing the Adaptec RAID Configuration Utility\n\nThe Adaptec RAID Configuration (ARC) utility is a BIOS-based utility that you can use to create arrays and manage controllers, disk drives and other devices.\n\nIntroduction to the ARC Utility\n\nThe ARC utility comprises these tools:\n\n- Logical Device Configuration—For creating and managing arrays, and initializing and rescanning disk drives (see Using the ARC Utility to Create and Manage Arrays on page 75).\n- Controller Settings—For modifying your controller and disk drive settings (see Using the ARC Utility to Modify Controller Settings on page 78).\n- Disk Utilities—For formatting or verifying disk drives (see Formatting and Verifying Disk Drives on page 80).\n\nCtrl-A or uEFI/HII?\n\nYour Adaptec RAID controller supports two interfaces to the BIOS-level RAID configuration options of the ARC utility: Ctrl-A and uEFI/HII. On servers that support the Unified Extensible Firmware Interface, or uEFI (version 2.10 or higher), the BIOS-level RAID configuration options are presented with a HII interface, or Human Interaction Infrastructure, rather than the Adaptec Ctrl-A interface described in this chapter. uEFI/HII provides an architecture-independent mechanism for initializing add-in cards, like the Adaptec RAID controller, and rendering contents to the screen in a uniform way.\n\nIn the HII interface, access to the RAID configuration options is provided through the server’s standard BIOS. How you access the BIOS varies, depending on the manufacturer, but typically it’s started by simply pressing DEL. Once you enter setup, navigate to the \"PMC maxView Storage Manager\" option, typically on the BIOS’ \"Advanced\" menu, then scan for and select a controller.\n\nFrom that point on, the HII menus and the Ctrl-A menus for configuring your RAID controller are almost identical. For example, the top-most menu contains the same three choices: Logical Device Configuration, Controller Settings, Disk Utilities (described above). Options in the lower-level menus are also similar.\n\nIn both interfaces, all the tools are menu-based and instructions for completing tasks appear on-screen. Menus can be navigated using the arrows, Enter, Esc, and other keys on your keyboard.\n\nThis chapter provides instructions for navigating and completing tasks with the Ctrl-A interface. To complete tasks with the HII interface:\n\n- Refer to the on-screen instructions for keyboard navigation and selection options.\n- Refer to the option descriptions in this chapter for details about individual RAID configuration settings and tasks.\n\nRunning the ARC Utility\n\nIf your Adaptec controller is connected to a RAID enclosure, power on your enclosure (or enclosures) before you power on your computer.\n\nStart or restart your computer. When prompted, press Ctrl+A.\n\nDuring boot up, if your system has insufficient memory this message displays:\n\n\"Adaptec RAID Configuration Utility will load after, system initialization. Please wait... Or press <Enter> Key to attempt loading the utility forcibly [Generally, not recommended]\"\n\nNote: The first time you power on your computer after you install a new controller, the BIOS may display a configuration that doesn’t match your system’s configuration. This is normal.\nUsing the ARC Utility to Create and Manage Arrays\n\nTo use the ARC utility to create and manage arrays, start the ARC utility (see `Running the ARC Utility` on page 74), select your controller (if you have more than one), then press `Enter`. Select `Logical Device Configuration` from the ARC main menu, then press `Enter`.\n\nFollow the on-screen instructions to create and manage arrays, and initialize, rescan, and erase disk drives.\n\nCreating a New Array\n\nTo begin creating an array, select `Create Arrays` from the Logical Device Configuration menu.\n\nOnly disk drives that can be used in a new array are available for selection. (Disk drives must be initialized before they can be used in an array. See `Initializing Disk Drives` on page 77 for more information.)\n\n**Note:**\n- To create a hybrid array that leverages the performance benefits of the SSDs in your system, you must select an equal number SSDs and HDDs. You can create a hybrid RAID1 or hybrid RAID10 only.\n- When you create an all SSD array, we recommend disabling all caching, including maxCache caching. If any caching is enabled when you create the array, you will be prompted to turn caching off.\n\nUse the Array Properties menu to modify the array's RAID level, size, name, stripe size, cache settings, and maxCache settings.\n\n**Note:** For more information about RAID levels and using disk drives to create arrays, see `Choosing a RAID Level` on page 25. For more information about maxCache, see `Modifying Cache Settings` on page 76.\n\nManaging Existing Arrays\n\nTo view or modify existing arrays, select `Manage Arrays` from the Logical Device Configuration menu.\n\nFrom the Manage Arrays menu, you can:\n- View the properties of an array. \n **Note:** Failed drives are displayed in a different text color.\n- Make an array bootable (see `Creating Bootable Arrays` on page 75).\n- Assign or remove hot spares.\n- Modify power management settings.\n- Change the cache settings for an array.\n- Delete an array.\n\n **Caution:** Before deleting an array, back up the data to avoid permanently losing it.\n\nCreating Bootable Arrays\n\n**Note:** You may need to change the system BIOS to modify the boot order. For more information, refer to your computer documentation.\n\nThe controller always uses the lowest numbered array as its bootable array.\n\nTo make an array bootable:\n\n1. Select `Manage Arrays` from the Logical Device Configuration menu.\n2. Select the array that you want to make bootable, then press `Ctrl+B`.\n\n **Note:** You cannot make an array bootable while it's building, verifying, or rebuilding.\n\n The array's number changes to Array 00, which makes this array the controller's boot array.\n\n3. Restart your computer.\nModifying Power Management Settings\n\nPower management settings switch the array to low power state when it is inactive for a specific time. To modify power management settings:\n\n1. Select Manage Arrays from the Logical Device Configuration menu.\n2. Select the array, then press Ctrl+W.\n\nIn the power management console, enter these details:\n\n<table>\n<thead>\n<tr>\n<th>Option</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Power Management</td>\n<td>When enabled, switches the array to low power state, when the array/drive is inactive.</td>\n</tr>\n<tr>\n<td>Slow Down Drive After</td>\n<td>The duration of inactive state of the array/drive after which it is slowed down to low power mode. This is an optional setting.</td>\n</tr>\n<tr>\n<td></td>\n<td>Note: The disk drive should support low power mode.</td>\n</tr>\n<tr>\n<td>Power Off Drive After</td>\n<td>The duration of inactive state of the array/drive after which it is powered off. This is an optional setting.</td>\n</tr>\n<tr>\n<td></td>\n<td>Note: Power Off Drive After duration should be greater than Slow Down Drive After Duration.</td>\n</tr>\n<tr>\n<td>Verify Drive After</td>\n<td>The regular time interval at which the system performs a health check of the array/drive.</td>\n</tr>\n</tbody>\n</table>\n\nModifying Cache Settings\n\nYou can modify the read and write cache settings for an array. You can also modify the maxCache settings. Adaptec maxCache uses the compatible Solid State Drives (SSDs) in your system as fast cache memory to improve performance for both read and write operations in I/O-intensive applications with mixed workloads.\n\nNote: maxCache SSD Caching is supported on Adaptec Series Q controllers only.\n\nTo modify the cache settings for an array:\n\n1. Select Manage Arrays from the Logical Device Configuration menu.\n2. Select the array, then press Ctrl+C.\n The Modify Cache Settings window opens.\n3. Enable or disable read caching.\n4. Press Tab.\n5. Enable or disable write caching:\n - Select Enable always for “write-back” caching\n - Select Enable with ZMM if your controller has battery backup or a zero-maintenance cache protection module\n - Select Disable for “write-through” caching\n6. Press Tab.\n7. Select the maxCache Read Cache setting (Enable/Disable).\n8. Select the maxCache Write Cache setting (Enable/Disable).\n9. Press Enter to accept the values.\nInitializing Disk Drives\n\nIf a disk drive appears grayed-out (unavailable for use in a new array), it may need to be initialized. To begin initializing a disk drive, select **Initialize Drives** from the Logical Device Configuration menu. You can initialize one drive or multiple drives. If an error occurs during initialization, the message \"Initializing drives...FAILED x of n\" is displayed. Press Enter to see a list of drives that failed to initialize. Press Esc to continue.\n\n**Caution:** Do not initialize a disk drive that is part of an array. Initializing a disk drive that’s part of an array may make the array unusable. Back up all data from your disk drive before you initialize it.\n\nRescanning Disk Drives\n\nTo begin rescanning a disk drive, select **Rescan Drives** from the Logical Device Configuration menu.\n\nSecure Erasing Disk Drives\n\nWhen you perform a secure erase on a disk drive, all data on that disk drive is completely and irretrievably eradicated. Secure erase performs three distinct writing passes to the disk drive being erased—it does not just write zeros.\n\nPerforming a secure erase takes up to six times longer than clearing (or zeroing) a disk drive; on a 2TB or 3TB drive, often it takes hours, possibly as long as a day! You may want to perform a secure erase only on disk drives that contain confidential or classified information.\n\n**Note:** To erase (or zero) a disk drive with non-classified information, you may choose to format it (see **Formatting and Verifying Disk Drives** on page 80) instead, or initialize it using maxView Storage Manager—both options take much less time than the secure erase option.\n\nTo begin a secure erase, select **Secure Erase** from the Logical Device Configuration menu, then select Y (yes). To return to the main Logical Device Configuration menu once the secure erase has begun, press Esc.\n\n**Note:** For newer SATA drives, you can choose to perform a Secure ATA Erase, which implements the secure erase feature at the drive firmware level. To start a Secure ATA Erase, select a SATA drive, then type Ctrl-S to open the Secure ATA Erase dialog. You will see this dialog only if the drive supports Secure ATA Erase.\n\nThe selected disk drive(s) cannot be used until the erase is complete.\n\nStopping a Secure Erase\n\nTo stop a secure erase in progress:\n\n1. In the Logical Device Configuration menu, select **Secure Erase**.\n2. Select the disk drive being secure erased, then press Ctrl+Q.\n \n The secure erase stops and you return to the main Logical Device Configuration menu.\n\nUninitializing Disk Drives\n\nUninitializes one or more physical drives. This option clears Adaptec meta-data and reserved space and any OS partitions from a drive; any existing data on the drive is destroyed. Drives can uninitialized only if they are not part of any array.\n\n**Note:** Uninitialized drives are surfaced to the OS as RAW Pass Through Devices. Typically, they are used with the controller in HBA mode. Uninitialized drives are also compatible with any HBA and can be exchanged with drives on the motherboard’s SATA interface. For more information about uninitialized devices and controller modes, see **General Controller Settings** on page 78.\n\nTo begin uninitializing a disk drive, select **Uninitialize Drives** from the Logical Device Configuration menu, then type Y to continue.\nUsing the ARC Utility to Modify Controller Settings\n\nThe ARC Controller Settings tool allows you to modify the settings of your controller and the disk drives connected to it.\n\nOpening the Controller Settings Tool\n\nTo open the ARC Controller Settings tool, start the ARC utility (see Running the ARC Utility on page 74), select Controller Settings from the ARC main menu, then press Enter.\n\nFollow the on-screen instructions to modify the settings of your controller and connected disk drives, as needed.\n\nApplying Changes and Exiting\n\n1. To exit the Controller Settings tool, press Esc until you are prompted to exit.\n If you modified any settings, you are prompted to save the changes before you exit.\n2. Select Yes to exit, then press any key to restart your computer.\n Any changes you made take effect after the computer restarts.\n\nModifying Your Controller’s Configuration\n\nNote: Default controller settings are suitable for most computers. We recommend that you do not change the default setting.\n\nTo modify your controller's basic settings, select Controller Configuration from the main Controller Settings menu.\n\nTo modify your controller’s power management settings, select Advanced Configuration.\n\nSome options may not be available for your controller.\n\nGeneral Controller Settings\n\nNote: Default settings are shown in bold type.\n\n<table>\n<thead>\n<tr>\n<th>Option</th>\n<th>Description</th>\n</tr>\n</thead>\n</table>\n| Drive’s Write Cache | When set to Enable All, write cache is enabled on all disk drives on the controller. (Enabling the write cache overrides any individual drive settings in maxView Storage Manager.) When set to Disable All, write cache is not used on the disk drives. When set to Drive Specific, write cache is enabled/disabled on a per-drive basis in maxView Storage Manager. \n Caution: When write cache is enabled, there is a slight possibility of data loss or corruption during a power failure. |\n<p>| Runtime BIOS | When enabled, the controller BIOS allows the controller to act as a bootable device. Disabling the BIOS allows another controller to act as a bootable device. |\n| Automatic Failover | When enabled, the controller automatically rebuilds an array when a failed disk drive is replaced. When disabled, the array must be rebuilt manually. |\n| Array Background Consistency Check | When enabled, the controller constantly verifies a redundant array. Note that there may be a significant performance reduction. Default is disabled. |\n| Array-based BBS Support | When enabled in systems that support BBS, the controller presents attached bootable devices up to the BIOS for boot device selection. This is relevant for logical arrays. Default is disabled. |\n| SATA Native Command Queuing (NCQ) | When enabled, NCQ is enabled. Disable this feature if you want to attach more than 48 SATA II disk drives. Only available with SATA II disk drives. |</p>\n<table>\n<thead>\n<tr>\n<th>Option</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Physical Drives Display During POST</td>\n<td>When enabled, connected disk drives are displayed during system Power On Self Test (POST). Displaying the disk drives adds a few seconds to the overall POST time. Default is disabled.</td>\n</tr>\n<tr>\n<td>DVD/CD-ROM Boot Support</td>\n<td>When enabled, the system can be booted from a bootable DVD/CD. (This setting is not available on all RAID controller models.)</td>\n</tr>\n<tr>\n<td>Removable Media Devices Boot Support</td>\n<td>When enabled, removable media devices, such as CD drives, are supported. (This setting is not available on all RAID controller models.)</td>\n</tr>\n<tr>\n<td>Alarm Control</td>\n<td>When enabled, the alarm sounds. Default is enabled. Note: When the alarm is turned off (disabled), it will remain off after a reboot.</td>\n</tr>\n<tr>\n<td>Default Background Task Priority</td>\n<td>Sets the default priority for background tasks on the controller (such as logical drive creation) to High, Medium, or Low. Default is High. Note: This setting applies to new tasks. It does not affect currently running tasks.</td>\n</tr>\n<tr>\n<td>LED Indication Mode</td>\n<td>When set to Activity and Fault, the drive activity LEDs blink to indicate I/O activity (randomly depending on I/O load) and fault (steady 1Hz). When set to Fault Only, the drive activity LEDs blink to indicate fault state only. For Series 6/6E controllers, default is Fault Only.</td>\n</tr>\n<tr>\n<td>Backplane Mode</td>\n<td>When set to Default, controller automatically sets the backplane mode to IBPI. To set the backplane mode explicitly, select IBPI, SGPIO, or Disabled. Default is IBPI. Note: With the default IBPI setting, the firmware sends a SGPIO "Backplane_TYPE" signal if it recognizes that a SGPIO Backplane is connected. If any connected SGPIO backplane does not support the "Backplane_TYPE" signal, or it does not support the IBPI protocol, you can manually set the Backplane Mode to "SGPIO".</td>\n</tr>\n<tr>\n<td>Selectable Performance Mode</td>\n<td>When set to Dynamic, performance criteria adjusts automatically based on controller usage, RAID level, and disk drive type. When set to OLTP/Db, performance criteria is optimized for transaction-oriented applications, such as data entry and retrieval. When set to User Defined, you are prompted to use the OS tools to set individual parameters (contact Adaptec support for more information). Default is Dynamic.</td>\n</tr>\n<tr>\n<td>Controller Mode</td>\n<td>• When set to RAID Mode, all RAID functions of the controller are enabled. • When set to Auto Volume Mode, RAID functions of the controller are enabled. Attached drives without Adaptec meta-data, but with an OS partition, are surfaced to the host operating system as RAW Pass Through devices (similar to JBODs on legacy Adaptec controllers), where the RAID layer of the controller firmware is bypassed when the host issues commands to the device. Attached drives without Adaptec meta-data and without OS partitions, are automatically configured as Simple Volumes (single drives with Adaptec meta-data). Auto Volume Mode enables DRAM caching on rotating media to help reduce latency and accelerate performance. • When set to HBA Mode, attached drives are surfaced as RAW devices. The intent of this mode is to allow the RAID controller to act and be used as an HBA. Changing into HBA mode is allowed only if there are no drives with Adaptec meta-data attached to the controller (see Uninitializing Disk Drives on page 77 for more information). Uninitialized drives are</td>\n</tr>\n</tbody>\n</table>\nOption | Description\n--- | ---\ncompatible with any HBA and can be exchanged with drives on the motherboard’s SATA interface. Default is RAID Mode.\n\n**Power Management Settings**\n\n*Note:* When power management is disabled, no related options will be displayed.\n\n*Note:* Make sure the operating system driver supports power management.\n\n*Note:* Default settings are shown in **bold** type.\n\n<table>\n<thead>\n<tr>\n<th>Option</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Power Management Settings</td>\n<td>When enabled, switches the system to low power state, based on the specified settings.</td>\n</tr>\n<tr>\n<td>Time Zone</td>\n<td>The time zone of the place in which the system is located. Time specific power management settings are implemented based on the set time zone. By default, it is set to 00:00. The valid range for the time zone settings is -12:00 to +12:00.</td>\n</tr>\n<tr>\n<td>Stay Awake Start</td>\n<td>The time from which the system should operate in the full power mode, irrespective of other power management settings, daily. By default it is set to <strong>00:00</strong>. The valid range is 00:00 to 23:59.</td>\n</tr>\n<tr>\n<td>Stay Awake End</td>\n<td>The time until which the system should operate in the full power mode, irrespective of other power management settings, daily. By default it is set to <strong>00:00</strong>. The valid range is 00:00 to 23:59.</td>\n</tr>\n<tr>\n<td>Spin Up Limit (Internal)</td>\n<td>The number of internal drives to be spun up at any given moment. By default it is set to 0. In the default setting, all the internal drives will spin up.</td>\n</tr>\n<tr>\n<td>Spin Up Limit (External)</td>\n<td>The number of external drives to be spun up at any given moment. By default it is set to 0. In the default setting, all the external drives will spin up.</td>\n</tr>\n</tbody>\n</table>\n\n**Checking Backup Unit Status**\n\nTo check the status of the controller’s flash backup unit, select **Backup Unit Status** from the Controller Settings menu. This option is available only if the controller is configured with a flash backup unit.\n\n**Formatting and Verifying Disk Drives**\n\nYou can use the ARC Disk Utilities tool to low-level format or verify your disk drives. (New disk drives are low-level formatted at the factory and do not need to be low-level formatted again.)\n\n*Caution:* Before you format a disk drive, back up all data. Formatting destroys all data on a disk drive.\n\nTo format or verify a disk drive:\n\n1. Start the ARC utility (see **Running the ARC Utility** on page 74).\n2. Select the controller you want, then press Enter.\n3. Select **Disk Utilities**.\n4. Select the disk drive you want, then press Enter.\n5. Select **Format Disk** or **Verify Disk Media**.\nLocating Disk Drives\n\nYou can use the Identify Drive feature to physically locate a disk drive by blinking the LED.\n\n**Note:** This feature is only available with disk drives that have an activity LED.\n\nTo locate a disk drive:\n\n1. Start the ARC utility (see *Running the ARC Utility* on page 74).\n2. Select the controller you want, then press Enter.\n4. Select the disk drive you want, then press Enter.\n5. Select Identify Drive, then press Enter.\n6. When you have finished locating your disk drive, press any key to stop the blinking.\n\nIdentifying Disk Drives\n\nYou can identify disk drives by viewing the list of disk drives on your system. Only physical drives that display during POST are shown.\n\nTo identify a disk drive:\n\n1. Start the ARC utility (see *Running the ARC Utility* on page 74).\n2. Select the controller you want, then press Enter.\n\nThe Disk Utilities view provides you with the following information:\n\n<table>\n<thead>\n<tr>\n<th>Location</th>\n<th>Model</th>\n<th>Rev#</th>\n<th>Speed</th>\n<th>Size</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CN1=DEV1</td>\n<td>The manufacturer</td>\n<td>The revision number of the disk drive.</td>\n<td>The speed of the disk drive.</td>\n<td>The size of the disk drive.</td>\n</tr>\n<tr>\n<td>Box0=Slot0</td>\n<td>information.</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Exp0=phy0</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nThe location information of a disk drive is determined by three types of connections:\n\n- Direct attached drives—The connection is determined by the cable connected to a device, for example CN1 (connector 1) is connected to DEV1 (device 1). For more information, see *Direct-attach Connections* on page 64.\n- Storage Enclosure Processor (SEP) managed devices—The connection is determined by an active backplane. Box0 (enclosure 0) is connected to slot0 (disk drive slot 0 in the enclosure). For more information, see *Backplane Connections* on page 65.\n- Expanders—The connections is determined by an expander. Exp0 (expander 0) is connected to phy0 (phy 0 within a connector). For more information, see *SAS Expander Connections* on page 65.\n\n**Note:** Devices other than disk drives (CDROM, tape drives, etc...) are listed in order after your system disk drives.\n\nViewing the Event Log\n\nThe BIOS-based event log records all firmware events, such as configuration changes, array creation, and boot activity.\n\nSome events are not stored indefinitely—the event log is cleared of any non-persistent events each time you restart your computer; additionally, once the log is full, new events overwrite old events.\n\nTo view the event log:\n\n1. Start the ARC utility (see *Running the ARC Utility* on page 74).\n2. Select the controller you want, then press Enter.\n3. When the ARC utility menu appears, press Ctrl+P.\n\n4. Select **Controller Log Information**, then press **Enter**.\n The current event log opens.\nUsing the Adaptec Flash Utility\n\nThis chapter describes how to use the Adaptec Flash Utility (AFU), a text-based DOS utility that you can use to update, save, or verify the RAID controller’s firmware.\n\n**Caution:** Although the AFU contains safeguards to prevent you from accidentally damaging your RAID controller’s flash contents, it is still important to use the AFU carefully and correctly to avoid rendering your RAID controller inoperable. We recommend that only advanced users familiar with working in DOS use the AFU. For more information, see *Managing Your Storage Space* on page 57.\n\n**System Requirements**\n\n- **DOS version 5.0 or later.**\n \n **Note:** You can’t run the AFU from a DOS command prompt window under any version of Windows.\n\n- At least 8 MB of extended memory.\n\n**Compatibility Notes**\n\n- Supports HIMEM.SYS; compatible with other DOS drivers running under HIMEM.SYS (for example, SMARTDRV.SYS and SETVER.SYS).\n\n- *Does not* support DOS extenders installed in memory, such as EMM386.SYS and DOS4GW.\n\n**Before You Begin**\n\n1. Obtain the firmware (see the following section).\n2. Create firmware disk (see *Creating the Firmware Update Disk* on page 83).\n\nThere are two ways to run the AFU:\n\n1. Using the AFU menus (see *Running the Menu-based AFU* on page 84)\n2. From the command line (see *Running the AFU from the Command Line* on page 84)\n\n**Obtaining the Firmware**\n\nTo obtain RAID controller firmware, go to:\n\n- Adaptec Installation DVD—Includes the AFU executable (AFU.exe) and a separate flash image. The flash image comprises a single User Flash Image (UFI) file.\n- Adaptec Web site—Download a new firmware file to get the most recent version of firmware/BIOS and AFU.\n\nSee [www.adaptec.com](http://www.adaptec.com) for more information.\n\n**Creating the Firmware Update Disk**\n\nTo create the firmware update disks:\n\n1. Copy these files to a USB flash drive or writable CD:\n - AFU.exe\n - Axxxx01.ufi\n \n where xxx is the model number of your controller.\n \n **Note:** Most controller model numbers have a suffix (for example, Adaptec RAID 6405). Check that the .ufi file is the correct file for your controller before copying.\n\n2. To use a menu-based AFU, see the following section.\n\n To run the AFU from the command line, see *Running the AFU from the Command Line* on page 84.\nRunning the Menu-based AFU\n\nTo run the menu-based AFU:\n\n1. Shut down your operating system and reboot to DOS from a bootable DOS floppy disk or from a DOS partition on a bootable drive. (You can use a disk drive connected to the controller you are updating.) If your computer isn’t set up to boot from the bootable floppy disk, enter the system setup utility and change the setting.\n\n2. Insert the firmware update disk (created using the steps above) containing AFU.exe\n\n3. At the DOS command prompt, type `AFU` with no arguments. The AFU’s main menu is displayed.\n\n4. Select **Select Controllers**, then select the Adaptec RAID controller(s) to be flashed.\n \n To update multiple RAID controllers in the same system, update the boot controller’s flash first, restart the computer, then update the flash for the remaining controllers.\n\n5. Select **Select an Operation**.\n\n6. Choose the operation you want, then follow the on-screen instructions to complete the task:\n\n - **Update flash image**—Updates all the flash components on a RAID controller with the flash image data from the UFI file.\n - **Save flash image**—Reads the contents of a RAID controller’s flash components and saves the data to a UFI file, which you can use to restore a RAID controller’s flash if required.\n - **Verify flash image**—Reads the contents of a RAID controller’s flash components and compares it to the contents of the specified UFI file.\n - **Display flash information**—Displays version information about a RAID controller’s flash components.\n\n7. Complete the flash operation and restart your computer before trying to use the RAID controller again. (You can not use your RAID controller while you are updating its flash.) The AFU processes the selected command and reports either success or an error message code.\n\nRunning the AFU from the Command Line\n\n*Note:* You can also run a menu-based AFU (see Running the Menu-based AFU on page 84).\n\nTo run the AFU from the command line:\n\n1. Shut down your operating system and reboot to DOS from a bootable DOS floppy disk or from a DOS partition on a bootable drive. (You can use a disk connected to the controller you’re updating.) If your computer isn’t set up to boot from the bootable floppy disk, enter the system setup utility to change the setting.\n\n2. Insert the firmware update disk containing AFU.exe.\n\n3. At the DOS command, type AFU followed by a command (see **AFU Commands** on page 84) and any switches you want.\n \n *Note:* To find a controller number, type `AFU LIST`, then press Enter.\n\n The AFU processes the command and reports either success or an error message code.\n\nTo update a RAID controller’s flash using the command line utility ARCCONF, see Updating the Flash Using the AFU Command Line on page 87.\n\nAFU Commands\n\nThis section lists the available AFU commands.\nList\nDisplays the AFU-supported RAID controllers installed on your computer. Also displays the ID numbers assigned to each controller.\nYou don’t have to restart the computer after completing this command.\n\nThis example shows a typical system response to a LIST command:\n\n```\nA:\\> AFU LIST\nAdaptec Flash Utility V4.0-0 B5749 (c)Adaptec Inc. 1999-2005.\nAll Rights Reserved.\nControllers Detected and Recognized:\nController #0 (03:05:00) Adaptec RAID 51645\n```\n\nSave\nSaves the contents of a RAID controller’s flash in a UFI file. The name of the UFI file is based on the controller type and can’t be changed.\nYou must restart the computer following a SAVE command.\nThe command syntax for the SAVE command is:\nAFU SAVE [/C<Controller ID>] [/D <UFI File Path>]\nThese switches are available:\n• /C <Controller ID>—One or more RAID controller IDs representing the set of RAID controllers on which to perform the specified command. The default is 0; if the computer has multiple RAID controllers, the AFU defaults to controller 0 unless you specify otherwise.\n For example:\n To specify a single RAID controller ID: /C 0\n To specify multiple IDs separated by commas: /C 0,2\n To indicate all RAID controllers: ALL\n If you are using multiple RAID controllers, you must specify the controller you want by using the /C switch; otherwise, the AFU displays an error message and exits.\n• /D <UFI File Path>—Specifies the path where the UFI files are located. If you do not specify the /D switch, the AFU looks for (or creates) its UFI files in the default location.\n You cannot specify the name of a UFI file, only its path. UFI filenames are predefined, based on the RAID controller type.\n In this example, the AFU saves flash contents from RAID controller 0 to a UFI file in the current default drive and directory:\n\n```\nA:\\> AFU SAVE /C 0\nIn this example, the AFU saves flash contents from Controller 1 to a UFI file in C:\\UFI_FILES:\n```\n\n```\nA:\\> AFU SAVE /C 1 /D C:\\UFI_FILES\n```\n\nUpdate\nUpdates the flash components of one or more RAID controllers on your computer from the flash image data in a UFI file. You must restart the computer following an UPDATE command.\nThe command syntax for the UPDATE command is:\nAFU UPDATE [/C<Controller ID>] [/D <UFI File Path>]\nThis example shows a typical system response after an update.\n\n```\nA:\\> AFU UPDATE /C 0\nAdaptec Flash Utility V4.0-0 B5749\n(c)Adaptec Inc. 1999-2005. All Rights Reserved.\nUpdating Controller 0 (Adaptec RAID 31205)\nReading flash image file (Build 5749)\n```\nAFU is about to update firmware on controllers Adaptec RAID 51645\n***PLEASE DO NOT REBOOT THE SYSTEM DURING THE UPDATE***\nThis might take a few minutes.\nWriting Adaptec RAID 51645 (4MB) Flash Image to controller 0...OK.\nVerifying...OK\nPlease restart the computer to allow firmware changes to take effect.\n\nVerify\nCompares the contents of each of the flash components on a RAID controller to the corresponding image in a UFI file, and indicates whether they match. After using the VERIFY command, you must restart the computer.\nThe command syntax for the VERIFY command is as follows:\nAFU VERIFY [/C<Controller ID>] [/D <UFI File Path>]\n\nThis example shows a typical system response after a VERIFY command.\nA:\\> AFU VERIFY /C 0\nAdaptec Flash Utility V4.0-0 B5749 (c)Adaptec Inc. 1999-2005.\nAll Rights Reserved.\nReading flash image file (Build 5748) Controller #0: Adaptec RAID 51645\nROM: Checksum: 797B [VALID] (Build 5748)\nFile: Checksum: 797B [VALID] (Build 5748)\nImage Compares Correctly\n\nVersion\nDisplays version information about the flash components on a RAID controller. After using the VERSION command, restart your computer.\nThe command syntax for the VERSION command is:\nAFU VERSION [/C<Controller ID>]\n\nThis example displays version information about all supported RAID controllers.\nA:\\> AFU VERSION /C 0\nAdaptec Flash Utility V4.0-0 B5749 (c)Adaptec Inc. 1999-2005.\nAll Rights Reserved.\nVersion Information for Controller #0 (Adaptec RAID 51645)\nA:\\> AFU VERSION /C ALL\n\nHelp\nDisplays a summary of AFU functions and command switches.\nFor example:\nA:\\> AFU HELP\nA:\\> AFU /?\nUpdating the Flash Using the AFU Command Line\n\n1. Create the firmware update disk (see Creating the Firmware Update Disk on page 83).\n2. Shut down your operating system and reboot to DOS from a bootable DOS floppy disk or from a DOS partition on a bootable drive. (You can use a disk connected to the controller you’re updating.) If your computer isn’t set up to boot from the bootable floppy disk or a bootable device other than a disk drive, enter the system setup utility to change the setting.\n3. Insert the firmware update disk containing AFU.exe\n4. At the DOS command, if you have multiple controllers and you don’t know the number of the controller you want to update, type AFU LIST, then press Enter. Otherwise, skip to the next step.\n5. At the DOS command, type AFU followed by a command (see AFU Commands on page 84) and any switches you want.\n6. Update the flash using the instructions suitable for your requirements:\n - To update a single RAID controller:\n \\[\n \\text{AFU UPDATE /C <cont_number>}\n \\]\n Where <cont_number> is the number of the RAID controller whose firmware you are updating. For example, to upgrade Controller 0, type AFU UPDATE /C 0\n - To update multiple RAID controllers:\n \\[\n \\text{AFU UPDATE /C <controller_number_a>,<controller_number_b>}\n \\]\n Where <controller_number_a> and <controller_number_b> are the numbers of the Adaptec RAID controllers whose firmware you are updating. For example, to upgrade controllers 0, 2, and 3, type AFU UPDATE /C 0, 2, 3\n - To update all RAID controllers simultaneously:\n \\[\n \\text{AFU UPDATE /C all}\n \\]\n Note: The UFI file identifies the RAID controllers, so you don’t have to worry about flashing the wrong controller.\n7. When prompted, insert the firmware disk.\n The AFU processes the command and reports either success or an error message code.\nController Alarm Connector Quick Reference\n\nThis appendix provides a reference guide for Adaptec RAID controller external alarm connectors.\n\nAdaptec RAID 7805/7805Q/71605/71605Q/71605E Alarm Connector Specification\n\n<table>\n<thead>\n<tr>\n<th>2274100-R</th>\n<th>ASR-7805 SGL</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2274200-R</td>\n<td>ASR-7805 Kit</td>\n</tr>\n<tr>\n<td>2274300-R</td>\n<td>ASR-7805Q SGL</td>\n</tr>\n<tr>\n<td>2274400-R</td>\n<td>ASR-71605 SGL</td>\n</tr>\n<tr>\n<td>2274500-R</td>\n<td>ASR-71605E SGL</td>\n</tr>\n<tr>\n<td>2274600-R</td>\n<td>ASR-71605Q SGL</td>\n</tr>\n</tbody>\n</table>\n\n- Adaptec RAID 7805/7805Q/71605/71605Q/71605E External Alarm Connector: Molex 22-28-4023 or equivalent\n- Alarm Mating Cable Connector: Molex 50-57-9002 or equivalent\n\nJ6:\n\n<table>\n<thead>\n<tr>\n<th>J6 Pin Number</th>\n<th>Signal</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2</td>\n<td>~2kHz Square Wave</td>\n<td>Open collector transistor</td>\n</tr>\n<tr>\n<td>1</td>\n<td>+3.3V</td>\n<td>—</td>\n</tr>\n</tbody>\n</table>\n\nAdaptec RAID 71685/72405/78165 Alarm Connector Specification\n\n<table>\n<thead>\n<tr>\n<th>2274700-R</th>\n<th>ASR-71685 SGL</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2274900-R</td>\n<td>ASR-72405 SGL</td>\n</tr>\n<tr>\n<td>2280900-R</td>\n<td>ASR-78165 SGL</td>\n</tr>\n</tbody>\n</table>\n\n- Adaptec RAID 71685/72405/78165 External Alarm Connector: Molex 22-28-4023 or equivalent\n- Alarm Mating Cable Connector: Molex 50-57-9002 or equivalent\n\nJ6:\n\n<table>\n<thead>\n<tr>\n<th>J6 Pin Number</th>\n<th>Signal</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2</td>\n<td>~2kHz Square Wave</td>\n<td>Open collector transistor</td>\n</tr>\n<tr>\n<td>1</td>\n<td>+3.3V</td>\n<td>—</td>\n</tr>\n</tbody>\n</table>\nSafety Information\nTo ensure your personal safety and the safety of your equipment:\n\n• Keep your work area and the computer clean and clear of debris.\n• Before opening the system cabinet, unplug the power cord.\n\nElectrostatic Discharge (ESD)\n\nCaution: ESD can damage electronic components when they are improperly handled, and can result in total or intermittent failures. Always follow ESD-prevention procedures when removing and replacing components.\n\nTo prevent ESD damage:\n\n• Use an ESD wrist or ankle strap and ensure that it makes skin contact. Connect the equipment end of the strap to an unpainted metal surface on the chassis.\n\n• Avoid touching the controller against your clothing. The wrist strap protects components from ESD on the body only.\n\n• Handle the controller by its bracket or edges only. Avoid touching the printed circuit board or the connectors.\n\n• Put the controller down only on an antistatic surface such as the bag supplied in your kit.\n\n• If you are returning the controller to Adaptec by PMC Product Support, put it back in its antistatic bag immediately.\n\nIf a wrist strap is not available, ground yourself by touching the metal chassis before handling the controller or any other part of the computer.\nTechnical Specifications\n\nEnvironmental Specifications\n\nNote: Adaptec RAID controllers require adequate airflow to operate reliably. The recommended airflow is 200 LFM (linear feet per minute), minimum. Forced airflow is required.\n\n<table>\n<thead>\n<tr>\n<th>Specification</th>\n<th>Requirements</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Ambient temperature with forced airflow</td>\n<td>0 °C to 55 °C</td>\n</tr>\n<tr>\n<td>Ambient temperature with Flash Backup Unit</td>\n<td>0 °C to 50 °C</td>\n</tr>\n<tr>\n<td>Relative humidity</td>\n<td>10% to 90%, non-condensing</td>\n</tr>\n<tr>\n<td>Altitude</td>\n<td>Up to 3,000 meters</td>\n</tr>\n</tbody>\n</table>\n\nNote: Ambient temperature is measured 1” from the RAID processor.\n\nDC Power Requirements\n\n<table>\n<thead>\n<tr>\n<th>Bus Type</th>\n<th>Description</th>\n<th>Requirements</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>PCIe</td>\n<td>Ripple and noise</td>\n<td>50 mV peak-to-peak (max)</td>\n</tr>\n<tr>\n<td>PCIe</td>\n<td>DC Voltage</td>\n<td>3.3 V ± 9%, 12 V ± 8%</td>\n</tr>\n</tbody>\n</table>\n\nCurrent Requirements\n\n<table>\n<thead>\n<tr>\n<th>Adaptec Model</th>\n<th>Typical Current</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Adaptec RAID 7805/7805Q</td>\n<td>0.1A @ 3.3 VDC; 1.5A @ 12.0 VDC</td>\n</tr>\n<tr>\n<td>Adaptec RAID 71605/71605Q</td>\n<td>0.1A @ 3.3 VDC; 1.6A @ 12.0 VDC</td>\n</tr>\n<tr>\n<td>Adaptec RAID 71605E</td>\n<td>0.1A @ 3.3 VDC; 1.5A @ 12.0 VDC</td>\n</tr>\n<tr>\n<td>Adaptec RAID 71685</td>\n<td>0.1A @ 3.3 VDC; 1.8A @ 12.0 VDC</td>\n</tr>\n<tr>\n<td>Adaptec RAID 72405</td>\n<td>0.1A @ 3.3 VDC; 1.8A @ 12.0 VDC</td>\n</tr>\n<tr>\n<td>Adaptec RAID 78165</td>\n<td>1.1A @ 3.3 VDC; 1.3A @ 12.0 VDC</td>\n</tr>\n</tbody>\n</table>\nIndex\n\nA\nactivity LED connector specifications 88\nAdaptec Flash Utility, See AFU\nAdaptec RAID Configuration utility 57\nAdaptec RAID Controller Configuration utility, See ARCCONF\nadapters, See controllers\nadvanced data protection 17\nAFU 58, 83\nAlarm Control setting 79\nARC 17, 36, 39, 59, 75, 76, 77, 78, 79, 80\nchecking flash backup unit 80\ncreating arrays 36, 75\ncreating bootable arrays 17, 39, 75, 76\nHII interface 36\ninitializing disk drives 75, 77\nmanaging arrays 75\nmodifying controller settings 59, 78\nopening Controller Settings tool 78\nrescanning disk drives 77\nsecure erasing disk drives 77\nstopping a secure erase 77\nuninitializing disk drives 77, 79\nARC Controller Settings 78\napplying changes 78\nexiting 78\nARCCONF 17, 57\nArray Background Consistency Check setting 78, 80\narray migration 17\nArray-based BBS Support setting 78\narrays 17, 25, 36, 37, 39, 67, 68, 69, 70, 71, 72, 75, 76\ncreating (ARC) 36, 75\ncreating (maxView Storage Manager) 37\ncreating bootable arrays 17, 39, 75, 76\nmaking an array bootable 37, 39\nmanaging with ARC 75\nnon-redundant 25, 67\nRAID 1 25, 68\nRAID 10 25, 69\nRAID 1E 25, 68\nRAID 5 25, 70, 71\nRAID 50 25, 71, 72\nRAID 6 25, 72\nRAID 60 25, 72\narrays (bootable) 35, 36, 40\naudible alarm 59\nautomatic failover 17\nAutomatic Failover setting 78\n\nB\nbackplane connections 33, 64, 65, 81\nbatteryless backup 29, 30\nboards, See controllers\nboot controller 28, 36\nbootable arrays 17, 35, 36, 37, 39, 40, 75, 76\ncreating 17, 35, 36, 39, 40, 75, 76\nC\ncards, See controllers\nCD-ROM Boot Support setting 79\nchecking flash backup unit 80\ncommand line interface (flash utility) 83, 84\ncommand line utility 57\nconcept 14, 15, 36, 57, 58, 60\nconnectors 64, 81\ncontents of controller kit 16\ncontrollers 14, 16, 17, 18, 25, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 39, 59, 61, 64, 65, 66, 67, 74, 75, 77, 78, 79, 80, 81, 83, 88, 90\nalarm connector specifications 88\nAlarm Control setting 79\nArray Background Consistency Check setting 78, 80\nArray-based BBS Support setting 78\narray-level features 17\nAutomatic Failover setting 78\nCD-ROM Boot Support setting 79\nconnecting disk drives 30, 32, 33\nconnecting external devices 30, 32, 33, 34\ndata protection 17\ndescriptions 14, 16, 17, 29, 31, 33, 59, 61, 65\ndisk drives 25, 29\nDrive's Write Cache setting 78\nevent log 81\nfigures 14, 16, 17, 29, 31, 33, 59, 61, 65\nfirmware 83\nflashing 18, 61\ninstallation options 27\ninstalling 29, 59\nmodifying general settings 77, 78\nmodifying settings with ARC 74, 78\nPhysical Drives Display During POST setting 79\nRAID levels 25, 33, 75\nRemovable Media Devices Boot Support setting 79\nresetting 18, 61\nRuntime BIOS setting 78\nSAS cables 16, 25, 35, 64, 66\nsetting boot controller 28, 36\nspecifications 90\nstandard features 17, 25, 29\ntroubleshooting 59\nupdating firmware 83\nupgrading firmware 18\nD\n\ndirect-attach connections 33, 64, 81\ndisk drives 17, 25, 29, 30, 32, 33, 34, 59, 60, 63, 64, 74, 75, 77, 79, 80, 81\nconnecting to controllers 30, 32, 33\nconnections 81\nexternal 30, 32, 33, 34\nfailure recovery 59, 60\nmultiple arrays 59, 60\nmultiple disk drives 60\nRAID 0 arrays 60\nwith hot spare 59, 60\nwithout hot spare 59, 60\nformatting 74, 77, 80\nidentifying 64, 81\ninitializing 75, 77\nrecovering from failure 59\nrescanning 77\nSAS identifiers 33, 63, 64\nsecure erasing 77\nstopping a secure erase 77\nsolid state 17, 25, 33\ntypes of connections 81\nuninitializing 77, 79\nverifying 74, 77, 80\nDKMS 40, 42\ndrive requirements 25\nDrive’s Write Cache setting 78\ndriver and operating system installation 28, 39, 40, 52\ndriver disk 40\ndriver installation 28, 35, 36, 40, 52\ndrivers 40, 41, 42, 44, 47, 48, 51, 52, 54\ninstalling on FreeBSD 52, 54\ninstalling on Solaris 52, 54\ninstalling on Windows 52\ninstalling with FreeBSD 40, 47\ninstalling with Linux 40, 41, 42, 44\ninstalling with VMware 40, 41, 47, 48\ninstalling with VMware 4.1 41\ninstalling with Windows 40, 42\ninstalling with XenServer 40, 51\ndrivers Debian 41\ninstalling with Linux 40, 41, 42, 44\ndrivers Ubuntu 41\ninstalling with Linux 40, 41, 42, 44\nDynamic Kernel Module Support 40, 42\n\nE\n\nelectrostatic discharge 89\nend devices 62\nevent log 81\nexpander connections 62, 64, 65, 66, 81\nexpander devices 62\nexternal devices 30, 32, 33, 34\n\nF\n\nfailed disk drives 59, 60\nmultiple arrays 59, 60\nmultiple disk drives 60\nRAID 0 arrays 60\nwithout hot spare 59, 60\nfirmware 83, 87\ncreating floppy disks 83, 87\nfirmware upgrades 18\nflashing controllers 18, 61\nfloppy disks for firmware update 83, 87\nformatting disk drives 74, 77, 80\nFreeBSD 40, 47, 52, 54\ndriver installation 52, 54\nOS installation 40, 47\n\nH\n\nhard disk 14\nhard disk drive 14\nhard drive, See disk drive\nHBA mode 77, 79\nHDA mode 61\nHDA mode jumper 61\nHII interface 36, 74\nhot spares 17\nHuman Interaction Infrastructure Interface (HII) 36, 74\nhybrid RAID 17, 33\n\nI\n\ninitializing disk drives 75, 77\ninstallation 27, 28, 29, 30, 32, 33, 34, 35, 36, 39, 40, 41, 42, 44, 47, 48, 51, 52, 59, 61, 64\nbackplane 33\ncontrollers 29, 59\ncreating a driver disk 40\ndirect-attach 33, 64\ndisk drives 30, 32, 33\ndriver 28, 35, 36, 40, 52\ndriver and FreeBSD 40, 47\ndriver and Linux 40, 42, 44\ndriver and operating system 28, 39, 40, 52\ndriver and VMware 40, 41, 47, 48\ndriver and Windows 40, 42\ndriver and XenServer 40, 51\nexisting operating system 28\nexternal devices 30, 32, 33, 34\ninstallation options 27\nsolid state drives 33, 61\nwith operating system 28\n\nK\n\nkit contents 16\nL\n\nLED Indication Mode 79\nLinux 40, 44\n OS installation 40, 44\nLinux installation 40, 42\nlow-profile bracket 16, 27\n installing 27\nlow-profile computer cabinet 25\n\nM\n\nmaxCache cache settings 75\nmaxCache Solid State Drive 33, 60, 61\n failed 60, 61\n installing 33, 61\nmaxView Storage Manager 37, 57\n creating arrays 37\n installing 57\nmini-SAS 33, 64\n direct connection 33\n overview 64\nmirroring 25\n\nN\n\nNCQ 17\nnon-redundant arrays 25, 67\n\nO\n\nonline expansion 17\noperating system installation 28, 39, 40, 52\noperating systems 16\n\nP\n\nparity 25\nphys 63\nPhysical Drives Display During POST setting 79\n\nR\n\nRAID 14, 17, 25, 67, 68, 69, 70, 71, 72\n non-redundant arrays 25, 67\n RAID 0 25, 67\n RAID 1 25, 68\n RAID 10 25, 69\n RAID 1E 17, 25, 68\n RAID 5 25, 70, 71\n RAID 50 25, 71, 72\n RAID 6 17, 25, 72\n RAID 60 17, 25, 72\nRAID controllers, See controllers\nRAID levels 25, 33, 75\nrecovering from disk drive failure 59\nRed Hat 40, 42\n OS installation 40, 42\nRedundant Array of Independent Disks, See RAID\nRemovable Media Devices Boot Support setting 79\nreplacing failed disk drives 59\n requirements 16, 25\n drive 25\nrescanning disk drives 77\nresetting controllers 18, 61\nRuntime BIOS setting 78\n\nS\n\nsafety information 29, 89\nSAS 14, 16, 25, 33, 35, 36, 62, 63, 64, 65, 66, 81\n 4-wide ports 63\n backplane connections 64, 65, 81\n cables 16, 25, 35, 64, 66\n comparison to parallel SCSI 62, 66\n connectors 63, 64\n description 33, 36, 62\n direct-attach connections 64, 81\n disk drives 33, 63, 64\n edge expanders 65\n end devices 62\n expander connections 62, 64, 65, 66, 81\n expander devices 62\n fanout expanders 65\n link speed 62\n links 62\n narrow connectors 64\n narrow ports 63\n phys 63\n ports 62, 63\n SAS address 63\n SAS cards 62\n SAS devices 62\n SAS domain 65\n terminology 62\n transceivers 62\n wide connectors 64\n wide ports 63\nSAS devices 62\nSAS disk drive identifiers 33, 63, 64\nsecure ATA erase 77\nsecure erasing disk drives 77\nstopping a secure erase 77\nSelectable Performance Mode 79\nSerial Attached SCSI, See SAS\nsoftware 57\nSolaris 52, 54\n driver installation 52, 54\nSolid State Drive (SSD) 17, 25, 33, 61\n installing 33, 61\nspecifications 90\nstorage management 57, 58\n Adaptec RAID Configuration utility 57\n AFU 58\n ARCCONF 57\n maxView Storage Manager 57\nstorage space 14\nSUSE installation 40, 44\nsystem requirements 16\n\nT\n\ntechnical specifications 90\nterminology 14, 38, 60, 62\nSAS 62\ntools 57, 58\nAdaptec RAID Configuration utility 57\nAFU 58\nARCCONF 57\nmaxView Storage Manager 57\ntopic 14, 17, 28, 42, 43, 44, 45, 46, 53, 54, 57, 59, 62, 83\ntroubleshooting tips 59\n\nU\n\nuEFI 36, 74\nUnified Extensible Firmware Interface (uEFI) 36, 74\nuninitializing disk drives 77, 79\nupdating firmware 83\nupgrading firmware 18\nutilities 57, 58\nAdaptec RAID Controller utility 57\n\nutilities (continued)\nAFU 58\nARCCONF 57\n\nV\n\nverifying disk drives 74, 77, 80\nVMware 40, 41, 47, 48\nOS installation 40, 41, 47, 48\n\nW\n\nWindows 40, 42, 52\ndriver installation 52\nOS installation 40, 42\n\nX\n\nXenServer 40, 51\nOS installation 40, 51\n\nZ\n\nzero maintenance cache protection 17, 29, 30"}}},{"rowIdx":70,"cells":{"id":{"kind":"string","value":"6c0bc88157c4ccc25bafec32664e6599f115f40a"},"text":{"kind":"string","value":"# Chapter 4\n\n## The GA Procedure\n\n<table>\n<thead>\n<tr>\n<th>Contents</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Overview: GA Procedure</td>\n<td>78</td>\n</tr>\n<tr>\n<td>Getting Started: GA Procedure</td>\n<td>80</td>\n</tr>\n<tr>\n<td>Initializing the Problem Data</td>\n<td>81</td>\n</tr>\n<tr>\n<td>Choosing the Problem Encoding</td>\n<td>83</td>\n</tr>\n<tr>\n<td>Setting the Objective Function</td>\n<td>84</td>\n</tr>\n<tr>\n<td>Controlling the Selection Process</td>\n<td>84</td>\n</tr>\n<tr>\n<td>Setting Crossover Parameters</td>\n<td>85</td>\n</tr>\n<tr>\n<td>Setting Mutation Parameters</td>\n<td>86</td>\n</tr>\n<tr>\n<td>Creating the Initial Generation</td>\n<td>86</td>\n</tr>\n<tr>\n<td>Monitoring Progress and Reporting Results</td>\n<td>87</td>\n</tr>\n<tr>\n<td>A Simple Example</td>\n<td>87</td>\n</tr>\n<tr>\n<td>Syntax: GA Procedure</td>\n<td>89</td>\n</tr>\n<tr>\n<td>PROC GA Statement</td>\n<td>90</td>\n</tr>\n<tr>\n<td>ContinueFor Call</td>\n<td>92</td>\n</tr>\n<tr>\n<td>Cross Call</td>\n<td>93</td>\n</tr>\n<tr>\n<td>Dynamic_array Call</td>\n<td>93</td>\n</tr>\n<tr>\n<td>EvaluateLC Call</td>\n<td>94</td>\n</tr>\n<tr>\n<td>GetDimensions Call</td>\n<td>95</td>\n</tr>\n<tr>\n<td>GetObjValues Call</td>\n<td>95</td>\n</tr>\n<tr>\n<td>GetSolutions Call</td>\n<td>95</td>\n</tr>\n<tr>\n<td>Initialize Call</td>\n<td>96</td>\n</tr>\n<tr>\n<td>MarkPareto Call</td>\n<td>97</td>\n</tr>\n<tr>\n<td>Mutate Call</td>\n<td>98</td>\n</tr>\n<tr>\n<td>Objective Function</td>\n<td>99</td>\n</tr>\n<tr>\n<td>PackBits Call</td>\n<td>100</td>\n</tr>\n<tr>\n<td>Programming Statements</td>\n<td>101</td>\n</tr>\n<tr>\n<td>ReadChild Call</td>\n<td>102</td>\n</tr>\n<tr>\n<td>ReadCompare Call</td>\n<td>103</td>\n</tr>\n<tr>\n<td>ReadMember Call</td>\n<td>103</td>\n</tr>\n<tr>\n<td>ReadParent Call</td>\n<td>104</td>\n</tr>\n<tr>\n<td>ReEvaluate Call</td>\n<td>104</td>\n</tr>\n<tr>\n<td>SetBounds Call</td>\n<td>104</td>\n</tr>\n<tr>\n<td>SetCompareRoutine Call</td>\n<td>105</td>\n</tr>\n<tr>\n<td>SetCross Call</td>\n<td>105</td>\n</tr>\n<tr>\n<td>SetCrossProb Call</td>\n<td>106</td>\n</tr>\n<tr>\n<td>SetCrossRoutine Call</td>\n<td>107</td>\n</tr>\n</tbody>\n</table>\nOverview: GA Procedure\n\nGenetic algorithms are a family of local search algorithms that seek optimal solutions to problems by applying the principles of natural selection and evolution. Genetic algorithms can be applied to almost any optimization problem and are especially useful for problems where other calculus-based techniques do not work, such as when the objective function has many local optima, when it is not differentiable or continuous, or when solution elements are constrained to be integers or sequences. In most cases genetic algorithms require more\ncomputation than specialized techniques that take advantage of specific problem structures or characteristics. However, for optimization problems with no such techniques available, genetic algorithms provide a robust general method of solution.\n\nIn general, genetic algorithms use some variation of the following procedure to search for an optimal solution:\n\n**Initialization:** An initial population of solutions is randomly generated, and the objective function is evaluated for each member of this initial generation.\n\n**Selection:** Individual members of the current generation are chosen stochastically either to parent the next generation or to be passed on to it, such that those members who are the fittest are more likely to be selected. A solution’s fitness is based on its objective value, with better objective values reflecting higher fitness.\n\n**Crossover:** Some of the selected solutions are passed to a crossover operator. The crossover operator combines two or more parents to produce new offspring solutions for the next generation. The crossover operator tends to produce new offspring that retain the common characteristics of the parent solutions, while combining the other traits in new ways. In this way new areas of the search space are explored, hopefully while retaining optimal solution characteristics.\n\n**Mutation:** Some of the next-generation solutions are passed to a mutation operator, which introduces random variations in the solutions. The purpose of the mutation operator is to ensure that the solution space is adequately searched to prevent premature convergence to a local optimum.\n\n**Repeat:** The current generation of solutions is replaced by the new generation. If the stopping criterion is not satisfied, the process returns to the selection phase.\n\nThe crossover and mutation operators are commonly called **genetic operators**. Selection and crossover distinguish genetic algorithms from a purely random search and direct the algorithm toward finding an optimum. Mutation is designed to ensure diversity in the search to prevent premature convergence to a local optimum.\n\nThere are many ways to implement the general strategy just outlined, and it is also possible to combine the genetic algorithm approach with other heuristic solution improvement techniques. In the traditional genetic algorithm, the solutions space is composed of bit strings, mapped to an objective function, and the genetic operators are modeled after biological processes. Although there is a theoretical foundation for the convergence of genetic algorithms formulated in this way, in practice most problems do not fit naturally into this paradigm. Modern research has shown that optimizations can be set up by using the natural solution domain (for example, a real vector or integer sequence) and applying crossover and mutation operators analogous to the traditional genetic operators, but more appropriate to the natural formulation of the problem. This is the approach, sometimes called **evolutionary computing**, taken in the GA procedure. It enables you to model your problem by using a variety of solution forms including sequences, integer or real vectors,\nBoolean encodings, and combinations of these. The GA procedure also provides you with a choice of genetic operators appropriate for these encodings, while permitting you to write your own.\n\nThe GA procedure enables you to implement the basic genetic algorithm by default, and to employ other advanced techniques to handle constraints, accelerate convergence, and perform multiobjective optimizations. These advanced techniques are discussed in the section “Details: GA Procedure” on page 115.\n\nAlthough genetic algorithms have been demonstrated to work well for a variety of problems, there is no guarantee of convergence to a global optimum. Also, the convergence of genetic algorithms can be sensitive to the choice of genetic operators, mutation probability, and selection criteria, so that some initial experimentation and fine-tuning of these parameters is often required.\n\n---\n\n### Getting Started: GA Procedure\n\nThe optimization problem is described by using programming statements, which initialize problem data and specify the objective, genetic operators, and other optimization parameters. The programming statements are executed once, and are followed by a RUN statement to begin the optimization process. The GA procedure enables you to define subroutines and designate them to be called during the optimization process to calculate objective functions, perform genetic mutation or crossover operations, or monitor and control the optimization. All variables created within a subroutine are local to that routine; to access a global variable defined within the GA procedure, the subroutine must have a parameter with the same name as the variable.\n\nTo set up a genetic algorithm optimization, your program needs to perform the following steps:\n\n1. Initialize the problem data, such as cost coefficients and parameter limits.\n\n2. Specify five basic optimization parameters:\n - **Encoding**: the general structure and form of the solution\n - **Objective**: the function to be optimized\n - **Selection**: how members of the current solution generation are chosen to propagate the next generation\n - **Crossover**: how the attributes of parent solutions are combined to produce new offspring solutions\n - **Mutation**: how random variation is introduced into the new offspring solutions to maintain genetic diversity\n\n3. Generate a population of solutions for the initial generation.\n\n4. Control the execution of the algorithm and record your results.\n\nThe following sections discuss each of these items in detail.\nInitializing the Problem Data\n\nThe GA procedure offers great flexibility in how you initialize the problem data. Either you can read data from SAS data sets that are created from other SAS procedures and DATA steps, or you can initialize the data with programming statements.\n\nIn the PROC GA statement, you can specify up to five data sets to be read with the DATA=n option, where n is a number from 1 to 5, that can be used to initialize parameters and data vectors applicable to the optimization problem. For example, weights and rewards for a knapsack problem could be stored in the variables WEIGHT and REWARD in a SAS data set. If you specify the data set with a DATA1= option, the arrays WEIGHT and REWARD are initialized at the start of the procedure and are available for computing the objective function and evaluating the constraints with program statements. You could store the number of items and weight limit constraint in another data set, as illustrated in the sample programming statements that follow:\n\n```\ndata input1;\n input weight reward;\ndatalines;\n 1 5\n 2 3\n 4 7\n 1 2\n 8 3\n 6 9\n 2 6\n 4 3\n ...;\n;\ndata input2;\n input nitems limit;\ndatalines;\n 10 20;\n;\nproc ga data1 = input1 / * creates arrays weight and reward */\n data2 = input2; /* creates variables nitems and limit */\nfunction objective( selected[*], reward[*], nitems);\n array x[1] /nosym;\n call dynamic_array(x, nitems);\n call ReadMember(selected,1,x);\n obj = 0;\n do i=1 to nitems;\n obj = obj + reward[x[i]];\n end;\n return(obj);\nendsub;\n\n[Other statements follow]\n```\nWith these statements, the DATA1= option first establishes the arrays weight and reward from the data set input1, and the DATA2= option causes the variables nitems and limit to be created and initialized from the data set input2. The reward array and the nitems variable are then used in the objective function.\n\nFor convenience in initializing two-dimensional data such as matrices, the GA procedure provides you with the MATRIXn= option, where n is a number from 1 to 5. A two-dimensional array is created within the GA procedure with the same name as the option, containing the numeric data in the specified data set. For example, a table of distances between cities for a traveling salesman problem could be stored as a SAS data set, and a MATRIX1= option specifying that data set would cause a two-dimensional array named MATRIX1 to be created containing the data at the start of the GA procedure. This is illustrated in the following program:\n\n```\ndata distance;\n input d1-d10;\ndatalines;\n 0 5 3 1 2 ... \n 5 0 4 2 6 ... \n 3 4 0 1 3 ... \n ... ;\nproc ga matrix1 = distance;\ncities = 10;\ncall SetEncoding('S10');\ncall SetObj('TSP','distances',matrix1);\n[Other statements follow]\n```\n\nIn this example, the data set distance is used to create a two-dimensional array matrix1, where \\( \\text{matrix1}[i,j] \\) is the distance from city \\( i \\) to city \\( j \\). The GA procedure provides a simple traveling salesman Problem (TSP) objective function, which is specified by the user with the SetObj call. The distances between locations are specified with the distances property of the TSP objective, which is set in the call to be matrix1. Note that when a MATRIXn= option is used, the names of variables in the data set are not transferred to the GA procedure as they are with a DATAn= option; only the numeric data are transferred.\n\nYou can also initialize problem data with programming statements. The programming statements in the GA procedure are executed before the optimization process begins. The variables created and initialized can be used and modified as the optimization progresses. The programming statement syntax is much like the SAS DATA step, with a few differences (see the section “Syntax: GA Procedure” on page 89). Special calls are described in the next sections that enable you to specify the objective function and genetic operators, and to monitor and control the optimization process. In the following program, a two-dimensional matrix is set up with programming statements to provide the distances for a 10-city symmetric traveling salesman problem, between locations specified in a SAS data set:\n\n```\ndata positions;\n input x y;\ndatalines;\n 100 230\n 50 20\n 150 100\n ... ;\n```\nChoosing the Problem Encoding\n\nProblem encoding refers to the structure or type of solution space that is to be optimized, such as real-valued fixed-length vectors or integer sequences. The GA procedure offers encoding options appropriate to several types of optimization problems. You specify the problem encoding with a SetEncoding CALL statement,\n\n```\ncall SetEncoding('encoding');\n```\n\nwhere the encoding string is a letter followed by a number, which specifies the type of encoding and the number of elements. The permitted letters and corresponding types of encoding are as follows:\n\n- **R** or **r**: real-valued vector. This type of encoding is used for general non-linear optimization problems.\n- **I** or **i**: integer-valued vector. This encoding is used for integer-valued problems. The integer size is 32 bits, which imposes a maximum value of 2,147,483,647 and a minimum value of −2,147,483,648 for any element of the vector. The integer vector encoding can also be used to represent bit vectors, where the 0–1 value of each bit in the integer vector is treated as a separate element. An example might be an assignment problem, where the positions within the vector represent different tasks, and the integer values represent different machines or other resources that might be applied to each task.\n- **B** or **b**: Boolean vector. Each element represents one true/false value.\n- **S** or **s**: sequence or permutation. In this encoding, each solution is composed of a sequence of integers ranging from 1 to the number of elements, with different solutions distinguished by different\norderings of the elements. This encoding is commonly used for routing problems such as the traveling salesman problem or for scheduling problems.\n\nFor example, the following statement specifies a 10-element integer vector encoding:\n\n```plaintext\ncall SetEncoding('I10');\n```\n\nFor problems where the solution form requires more than one type of encoding, you can specify multiple encodings in the `encoding` string. For example, if you want to optimize the scheduling of 10 tasks and the assignment of resources to each task, you could use a segmented encoding, as follows:\n\n```plaintext\ncall SetEncoding('I10S10');\n```\n\nHere the I10 (10-element integer vector) is assigned to the first segment, and represents the resource assignment. The S10 (10-element sequence) is assigned to a second segment, and represents the sequence of tasks. The use of segmented encodings is described in the section “Using Multisegment Encoding” on page 115.\n\n---\n\n**Setting the Objective Function**\n\nBefore executing a genetic algorithm, you must specify the objective function to be optimized. Either you can define a function in your GA procedure input and designate it to be your objective function with the `SetObjFunc` call, or you can specify an objective function that the GA procedure provides with a `SetObj` call. The GA procedure currently supports the traveling salesman problem objective.\n\n---\n\n**Controlling the Selection Process**\n\nThere are two competing factors that need to be balanced in the selection process: selective pressure and genetic diversity. Selective pressure, the tendency to select only the best members of the current generation to propagate to the next, is required to direct the genetic algorithm to an optimum. Genetic diversity, the maintenance of a diverse solution population, is also required to ensure that the solution space is adequately searched, especially in the earlier stages of the optimization process. Too much selective pressure can lower the genetic diversity so that the global optimum is overlooked and the genetic algorithm converges prematurely. Yet, with too little selective pressure, the genetic algorithm might not converge to an optimum in a reasonable time. A proper balance between the selective pressure and genetic diversity must be maintained for the genetic algorithm to converge in a reasonable time to a global optimum.\n\nThe GA procedure uses a standard technique for the selection process commonly known as tournament selection. In general, the tournament selection process randomly chooses a group of members from the current population, compares their fitness, and selects the fittest from the group to propagate to the next generation. Tournament selection is one of the fastest selection methods, and it offers good control over the selection pressure.\n\nYou can control the selective pressure by specifying the tournament size, the number of members chosen to compete in each tournament. This number should be 2 or greater, with 2 implying the weakest selection pressure. Tournament sizes from 2 to 10 have been successfully applied to various genetic algorithm\noptimizations, with sizes over 4 or 5 considered to represent strong selective pressure. This selection option is chosen with the following `SetSel` call:\n\n```fortran\n call SetSel('tournament', 'size', size);\n```\n\nwhere `size` is the desired tournament size.\n\nFor tournament size of 2, you can further weaken the selective pressure by specifying a probability for selecting the most fit solution from the 2 competing solutions. By default this probability is 1, but the GA procedure permits you to set it to a value between 0.5 (equivalent to pure random selection) and 1. This selection option is chosen with the following `SetSel` call:\n\n```fortran\n call SetSel('duel', 'pbest', bestprob);\n```\n\nwhere `bestprob` is the probability for choosing the most fit solution. This option can prove useful when conventional tournament selection tends to result in premature convergence.\n\nOne potential problem with tournament selection is that it does not guarantee that the best solution in the current generation is passed on to the next. To resolve this problem, the GA procedure enables you to specify an `elite` parameter, which ensures that the very best solutions are passed on to the next generation unchanged by mutation or crossover. Use the `SetElite` call:\n\n```fortran\n call SetElite(elite);\n```\n\nwhere `elite` is an integer greater than or equal to 0. The GA procedure preserves the `elite` best solutions in the current generation and ensures that they are passed on to the next generation unchanged. When writing out the final solution population, the first `elite` members are the best of the generation and are sorted by their fitness, such that the fittest is first. By default, if you do not call `SetElite` in your program, an `elite` value of 1 is used. Setting the `elite` parameter to a higher number accelerates the convergence of the genetic algorithm; however, it can also lead to premature convergence before reaching a global optimum, so it should be used with care.\n\nIf you do not call `SetSel` in your input, then the default behavior for the GA procedure is to use tournament selection with size 2.\n\n---\n\n**Setting Crossover Parameters**\n\nThere are two crossover parameters that need to be specified: the crossover probability and the crossover operator. Members of the current generation that have passed the selection process either go to the crossover operator or are passed unchanged into the next generation, according to the crossover probability. To set the probability, you use a `SetCrossProb` call:\n\n```fortran\n call SetCrossProb(prob);\n```\n\nwhere `prob` is a real number between 0 and 1. A value of 1 implies that the crossover operator is always applied, while 0 effectively turns off crossover. If you do not explicitly set the crossover probability with this call, a default value of 0 is used.\n\nThe GA procedure enables you to choose your crossover operator from several standard crossover operators appropriate for each type of encoding, or to code your own crossover operator as a subroutine. To specify one of the crossover operators provided by the GA procedure, use a `SetCross` call. See the section “Crossover Operators” on page 116 for more detail on the available operators. To supply your own operator, use a `SetCrossRoutine` call:\ncall SetCrossRoutine( 'routine' );\n\nwhere *routine* is the name of your crossover subroutine. See the section “Defining User Genetic Operators” on page 126 for a description of defining genetic operators with user subroutines. If the crossover probability is greater than 0, you must use a SetCross or SetCrossRoutine call to set the crossover operator.\n\nAfter initialization, you can reset any of the crossover parameters or their properties during the optimization process by calling one of the preceding routines from a user update routine. This makes it possible to adapt the crossover operators as desired in the optimization process.\n\n### Setting Mutation Parameters\n\nThere are two mutation parameters: the mutation probability and the mutation operator. Members of the next generation are chosen to undergo mutation with the mutation probability you specify. To set the mutation probability, you use a SetMutProb call:\n\n```\ncall SetMutProb( prob );\n```\n\nwhere *prob* is a real number between 0 and 1. This probability is usually fairly low (0.05 or less), since mutation tends to slow the convergence of the genetic algorithm. If you do not explicitly set the mutation probability with this call, a default value of 0 is used.\n\nThe GA procedure enables you to choose your mutation operator from several standard mutation operators appropriate for each type of encoding, or to code your own mutation operator as a subroutine. To specify one of the mutation operators provided by the GA procedure, use a SetMut call. See the section “Mutation Operators” on page 122 for more detail on the available operators. To supply your own operator, use a SetMutRoutine call:\n\n```\ncall SetMutRoutine( 'routine' );\n```\n\nwhere *routine* is the name of your mutation subroutine. See the section “Defining User Genetic Operators” on page 126 for a description of defining genetic operators with user subroutines. If the mutation probability is greater than 0, you must use a SetMut or SetMutRoutine call to set the mutation operator.\n\nAfter initialization, you can reset any of the mutation parameters or their properties during the optimization process by calling one of the preceding routines from a user update routine. This makes it possible to adapt the mutation operators to create more or less diversity as needed in the optimization process.\n\n### Creating the Initial Generation\n\nThe last step in the initialization for the genetic algorithm optimization is to create the initial solution population, the first generation. The GA procedure provides you with the Initialize call to accomplish this task. The procedure provides several options for initializing the first population or reinitializing the solution population during the optimization process. For example, you can specify a data set in the FIRSTGEN= option of the PROC GA statement to be read to populate the initial generation, and use the initialize call:\n\n```\ncall Initialize( '_dataset_', PopulationSize );\n```\n\nOther possible initialization options include generating solutions uniformly distributed over the solution domain, executing a user-defined initialization routine, carrying over a portion of the previous population (for\nreinitialization), or any combination of those actions. See the section “Initialize Call” on page 96 for a full explanation of initialization actions.\n\nMonitoring Progress and Reporting Results\n\nThe GA procedure enables your program to monitor and alter parameters during the optimization process and record final results.\n\nIf a data set is specified in the LASTGEN= option of the PROC GA statement, then the last generation of solutions is written to the data set. See the section “PROC GA Statement” on page 90 for a description of the data set created by the LASTGEN= option.\n\nYou can define a subroutine and designate it to be called at each iteration in an update phase, which occurs after the evaluation phase and before selection, crossover, and mutation. Your subroutine can check solution values and update and store variables you have defined, adjust any of the optimization parameters such as the mutation probability or elite value, or check termination criteria and end the optimization process. An update routine can be especially helpful in implementing advanced techniques such as multiobjective optimization. You can specify an update subroutine with a SetUpdateRoutine call:\n\n```plaintext\ncall SetUpdateRoutine('routine');\n```\n\nwhere `routine` is the name of your subroutine to be executed at each iteration.\n\nYou can set the maximum number of iterations permitted for the optimization process with the MAXITER= option in the PROC GA statement. If none is specified, a default value of 500 iterations is used. You can also control the number of iterations dynamically in your program by using the ContinueFor call:\n\n```plaintext\ncall ContinueFor(n);\n```\n\nwhere `n` is the number of iterations to permit beyond the current iteration. A value of 0 ends the optimization process at the current iteration. One common way this call might be used is to include it in the logic of an update subroutine declared in the SetUpdateRoutine call. The update subroutine could check the objective values and end the optimization process when the optimal value of the objective function has not improved for a specific number of iterations. A ContinueFor call overrides an iteration limit set with the MAXITER= option.\n\nTo perform post processing of the optimization data, you can use a SetFinalize call to instruct the GA procedure to call a subroutine you have defined, after the last iteration:\n\n```plaintext\ncall SetFinalize('routine');\n```\n\nwhere `routine` is the name of a subroutine you have defined. Your finalize subroutine could perform some post processing tasks, such as applying heuristics or a local optimization technique to try to improve the final solution.\n\nA Simple Example\n\nThe example that follows illustrates the application of genetic algorithms to function optimization over a real-valued domain. It finds the minimum of the Shubert function:\nwhere $-10 \\leq x_i \\leq 10$ for $i = 1, 2$.\n\n```plaintext\nproc ga seed = 12 maxiter = 30;\n/* the objective function to be optimized */\nfunction shubert(selected[*]);\n array x[2] /nosym;\n call ReadMember(selected,1,x);\n x1 = x[1];\n x2 = x[2];\n sum1 = 0;\n do i = 1 to 5;\n sum1 = sum1 + i * cos((i+1)* x1 + i);\n end;\n sum2 = 0;\n do i = 1 to 5;\n sum2 = sum2 + i * cos((i+1) * x2 + i);\n end;\n result = sum1 * sum2;\n return(result);\nendsub;\n/* Set the problem encoding */\ncall SetEncoding('R2');\n/* Set upper and lower bounds on the solution components */\narray LowerBound[2] /nosym (-10 -10);\narray UpperBound[2] /nosym (10 10);\ncall SetBounds(LowerBound, UpperBound);\n/* Set the objective function */\ncall SetObjFunc('shubert',0);\n/* Set the crossover parameters */\ncall SetCrossProb(0.65);\ncall SetCross('Heuristic');\n/* Set the mutation parameters */\ncall SetMutProb(0.15);\narray del[2] /nosym (0.2 0.2);\ncall SetMut('Delta','nchange', 1, 'delta',del);\n/* Set the selection criteria */\ncall SetSel('tournament','size', 2);\ncall SetElite(2);\n/* Initialize the first generation, with 120 random solutions */\ncall Initialize('DEFAULT',120);\n/* Now execute the Genetic Algorithm */\nrun;\nquit;\n```\n\nAt the beginning of the program, the PROC GA statement sets the initial random number seed and sets the maximum number of iterations to 30.\n\nA routine to compute the objective function (function shubert) is then defined. This function is called by the GA procedure once for each member of the solution population at each iteration. Note that the GA procedure passes the array selected as the first parameter of the function, and the function uses that array to\nobtain the selected solution elements with a ReadMember call, which places the solution in the array x. The second parameter of the ReadMember call is 1, specifying that segment 1 of the solution be returned, which in this case is the only segment. The programming statements that follow compute the value of the objective function and return it to the GA procedure.\n\nAfter the function definition, the ‘R2’ passed to the SetEncoding call specifies that solutions are single-segment, with that segment containing two elements that are real-valued. Next, a lower bound of –10 and an upper bound of 10 are set for each solution element with the SetBounds call. The SetObjFunc call specifies the previously defined Shubert function as the objective function for the optimization; the second parameter value of 0 indicates that a minimum is desired. The SetCrossProb call sets the crossover probability to 0.65, which means that, on average, 65% of the solutions passing the selection phase will undergo the crossover operation. The crossover operator is set to the heuristic operator by the SetCross call. Similarly, the mutation probability is set to 0.15 with the SetMutProb call, and the delta operator is set as the mutation operator with the SetMut call. The selection criteria are then set: a conventional tournament of size 2 is specified with the SetSel call, and an elite value of 2 is specified with the SetElite call. The elite value implies that the best two solutions of each generation are always carried over to the next generation unchanged by mutation or crossover. The last step before beginning the optimization is the Initialize call. This call sets the population size at 120, and specifies the default initialization strategy for the first population. For real encoding, this means that an initial population randomly distributed between the upper and lower bounds specified in the SetBounds call is generated. Finally, when the RUN statement is encountered, the GA procedure begins the optimization process. It iterates through 30 generations, as set by the MAXITER= option.\n\nThe Shubert function has 760 local minima, 18 of which are global minima, with a minimum of –186.73. If you experiment with different random seeds with the SEED= option, PROC GA generally converges to a different global minimum each time. Figure 4.1 shows the output for the chosen seed.\n\n**Figure 4.1** Shubert Function Example Output\n\n<table>\n<thead>\n<tr>\n<th>PROC GA Optimum Values</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Objective</strong></td>\n</tr>\n<tr>\n<td>-186.7309031</td>\n</tr>\n<tr>\n<td><strong>Solution</strong></td>\n</tr>\n<tr>\n<td><strong>Element</strong></td>\n</tr>\n<tr>\n<td>1</td>\n</tr>\n<tr>\n<td>2</td>\n</tr>\n</tbody>\n</table>\n\n**Syntax: GA Procedure**\n\nTo initialize your data and describe your model, you use programming statements with a syntax similar to the SAS DATA step, augmented with some special function calls to communicate with the genetic algorithm optimizer. Most of the programming statements used in the SAS DATA step can be used in the GA procedure, and these are described fully in the SAS Statements: Reference and Base SAS documentation. Following is an alphabetical list of the statements and special function calls used.\nThe PROC GA statement invokes the GA procedure. The following options are used with the PROC GA statement.\n\n**PROC GA options**\n\n- ContinueFor Call\n- Cross Call\n- Dynamic_array Call\n- EvaluateLC Call\n- GetDimensions Call\n- GetObjValues Call\n- GetSolutions Call\n- Initialize Call\n- MarkPareto Call\n- Mutate Call\n- Objective Call\n- PackBits Call\n- Program Statements\n- ReadChild Call\n- ReadCompare Call\n- ReadMember Call\n- ReadParent Call\n- ReEvaluate Call\n- SetBounds Call\n- SetCross Call\n- SetCrossProb Call\n- SetCrossRoutine Call\n- SetElite Call\n- SetEncoding Call\n- SetFinalize Call\n- SetMut Call\n- SetMutProb Call\n- SetMutRoutine Call\n- SetObj Call\n- SetObjFunc Call\n- SetProperty Call\n- SetSel Call\n- SetUpdateRoutine Call\n- ShellSort Call\n- Shuffle Call\n- UnpackBits Function\n- UpdateSolutions Call\n- WriteChild Call\n- WriteMember Call\n\n---\n\n**PROC GA Statement**\n\n**PROC GA options**\n\nThe PROC GA statement invokes the GA procedure. The following options are used with the PROC GA statement.\n**DATA**=SAS-data-set\n\nspecifies a data set containing data required to specify the problem, where \\( n \\) is an integer from 1 to 5. The data set is read and variables created matching the variables of the data set. If the data set has more than one observation, then the newly created variables are vector arrays with the size equal to the number of observations.\n\n**FIRSTGEN**=SAS-data-set\n\nspecifies a SAS data set containing the initial solution generation. Different segments in the solution should be identified by variable names consisting of a letter followed by numbers representing the elements in the segments, in alphabetical order. For example, if the first segment of the solution uses real encoding and contains 10 elements, it should be represented by the numeric variables A1, A2, ..., A10. A second segment with integer encoding and five elements would be specified in the variables B1, B2, ..., B5. For Boolean encoding each Boolean element is represented by one variable in the data set, and for sequence encoding each position in the sequence is represented by one variable. If the data set contains a field named OBJECTIVE, then the value of that field becomes the objective value for that solution at initialization time (overriding the value computed by the input objective function), unless the field value is a missing value. The **FIRSTGEN**= and **LASTGEN**= options are designed to work together, so that a data set generated from a run of the GA procedure with a **LASTGEN**= option can be specified in the **FIRSTGEN**= option of a subsequent run of the GA procedure, to continue the optimization from where it finished. If the number of observations in the data set is less than the population size specified in the Initialize call, additional members are generated as specified in the Initialize call to complete the population. This feature makes it easy to seed an initial randomly generated population with chosen superior solutions generated by heuristics or a previous run of the GA procedure. If the data set contains more observations than the population size, the population is filled starting at the first observation, and the additional observations are not used.\n\n**LASTGEN**=SAS-data-set\n\nspecifies a SAS data set into which the final solution generation is written. Different segments in the solution are identified by variable names consisting of a letter followed by numbers representing the elements in the segments, in alphabetical order. For example, if the first segment of the solution uses real encoding and contains 10 elements, it would be represented by the numeric variables A1, A2, ..., A10. A second segment with integer encoding and five elements would be specified in the variables B1, B2, ..., B5. For Boolean encoding each Boolean element is represented by one variable in the data set, and for sequence encoding each position in the sequence is represented by one variable. In addition to the solutions elements, the final objective value for each solution is output in the OBJECTIVE variable. The **FIRSTGEN**= and **LASTGEN**= options are designed to work together, so that a data set generated with a **LASTGEN**= option can be specified in the **FIRSTGEN**= option of a later run of the GA procedure.\n\n**LIBRARY**=library-list\n\nspecifies a library or group of libraries for the procedure to search to resolve subroutine or function calls. The libraries can be created by using PROC FCMP and PROC PROTO. This option supplements the action of the CMPLIB= SAS option, but it permits you to designate libraries specific to this procedure invocation. Use the libref.catalog format to specify the two-level name of the library; library-list can be either a single library, a range of library names, or a list of libraries. The following examples demonstrate the use of the **LIBRARY**= option.\n\n```\nproc ga library = sasuser.xlib;\nproc ga library = xlib1-xlib5;\n```\nproc ga library = (sasuser.xlib xlib1-xlib5 work.example);\n\n**MATRIX**\n\n**n** = **SAS-data-set** \nSpecifies a data set containing two-dimensional matrix data, where *n* is an integer from 1 to 5. A two-dimensional numeric array with the same name as the option is created and initialized from the data set. This option is provided to facilitate the input of tabular data to be used in setting up the optimization problem. Examples of data that might be provided by this option include a distance matrix for a traveling salesman problem or a matrix of coefficients for linear constraints.\n\n**MAXITER=**\n\n**n** \nSpecifies the maximum number of iterations to permit for the optimization process. A ContinueFor call overrides a limit set by this option.\n\n**NOVALIDATE=**\n\n**n** \nControls the amount of solution validity checking performed by the procedure. By default, the procedure verifies that valid solutions are being supplied at initialization and when the solution population is being updated by genetic operators or other user actions. If a solution segment has elements that exceed bounds set by a SetBounds call, those elements will be reset to the bound and a warning will be issued. If a solution segment contains other illegal values, an error will be signaled. This action is useful for maintaining the validity of the optimization and avoiding some errors that are often difficult to trace. However, this activity does consume CPU time, and you might want to use a strategy where you generate infeasible solutions at initialization or via genetic operators and then repair the solutions later in an update or objective routine. The NOVALIDATE= option enables you to do so, by turning off the validation checks. If *n* is 1, validation is turned off for initialization only, and if *n* is 2, validation is turned off for update only. If *n* is 3, all solution validity checking is turned off.\n\n**NOVALIDATEWARNING=**\n\n**n** \nControls the output of warning messages related to solution validation checking. Depending on the value of the NOVALIDATE= option, warning messages will be issued when the procedure repairs initial or updated solution segments to fit within bounds set with the SetBounds call. If *n* is 1, validation warnings are turned off for initialization only; and if *n* is 2, validation warnings are turned off for update only. If *n* is 3, all solution validation warnings are turned off.\n\n**SEED=**\n\n**n** \nSpecifies an initial seed to begin random number generation. This option is provided for reproducibility of results. If it is not specified, or if it is set to 0, a seed is chosen based on the system clock. The SEED value should be a nonnegative integer less than $2^{31} - 1$.\n\n---\n\n**ContinueFor Call**\n\n```sas\ncall ContinueFor ( niter ) ;\n```\n\nThe ContinueFor call sets the number of additional iterations for the genetic algorithm optimization. The input to the ContinueFor subroutine is as follows:\n\n- **niter** specifies that the optimization continue for *niter* more iterations. \nTo stop at the current iteration, set *niter* to 0.\nCross Call\n\ncall Cross ( selected, seg, type<, parameter1, parameter2, ... > ) ;\n\nThe Cross call executes a genetic crossover operator from within a user subroutine. The inputs to the subroutine are as follows:\n\n* `selected` is an array that specifies the solutions to be crossed.\n* `seg` is the desired segment of the solution to which the crossover operator should be applied.\n* `type` is the type of crossover operator to apply, which also determines the number and type of parameters expected.\n* `parameter1-n` are optional parameters applicable to some operators.\n\nThe accepted values for `type` and the corresponding parameters are summarized in Table 4.2.\n\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Encodings</th>\n<th>Parameters</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>‘arithmetic’</td>\n<td>real, integer</td>\n<td></td>\n</tr>\n<tr>\n<td>‘cycle’</td>\n<td>sequence</td>\n<td></td>\n</tr>\n<tr>\n<td>‘heuristic’</td>\n<td>real</td>\n<td></td>\n</tr>\n<tr>\n<td>‘null’</td>\n<td>all encodings</td>\n<td></td>\n</tr>\n<tr>\n<td>‘order’</td>\n<td>sequence</td>\n<td></td>\n</tr>\n<tr>\n<td>‘pmatch’</td>\n<td>sequence</td>\n<td></td>\n</tr>\n<tr>\n<td>‘simple’</td>\n<td>real, integer, Boolean</td>\n<td><code>alpha</code></td>\n</tr>\n<tr>\n<td>‘twopoint’</td>\n<td>real, integer, Boolean</td>\n<td><code>alpha</code></td>\n</tr>\n<tr>\n<td>‘uniform’</td>\n<td>real, integer, Boolean</td>\n<td><code>alpha, p</code></td>\n</tr>\n</tbody>\n</table>\n\nThe parameters are as follows:\n\n* `alpha` is a number such that $0 < \\alpha \\leq 1$.\n* `p` is a probability such that $0 < p \\leq 0.5$.\n\nThe Cross call should be made only from within a user crossover subroutine. The precise action of these crossover operators is described in the section “Crossover Operators” on page 116.\n\nDynamic_array Call\n\ncall Dynamic_array ( arrayname, dim1<, dim2, ..., dim6> ) ;\n\nThe Dynamic_array call allocates a numeric array. The inputs to the Dynamic_array call are as follows:\n\n* `arrayname` is a previously declared array, whose dimensions are to be re-allocated.\n* `dim1` is the size of the first dimension.\n* `dim2, ... , dim6` are optional. Up to six dimensions can be specified.\nChapter 4: The GA Procedure\n\nThe Dynamic_array call is normally used to allocate working arrays when the required size of the array is data-dependent. It is often useful in user routines for genetic operators or objective functions to avoid hard-coding array dimensions that might depend on segment length or population size. The array to be allocated must first be declared in an ARRAY statement with the expected number of dimensions, as in the following example:\n\n```fortran\nsubroutine sub(nx, ny);\narray x[1] /nosym;\ncall dynamic_array(x, nx);\narray xy[1,1] /nosym;\ncall dynamic_array(xy, nx, ny);\n...\n```\n\nEvaluateLC Call\n\ncall EvaluateLC (lc, results, sum, selected, seg<, child>);\n\nThe EvaluateLC call evaluates linear constraints. The inputs to the EvaluateLC subroutine are as follows:\n\n- **lc**: is a two-dimensional array representing the linear constraints.\n- **results**: is a numeric array to receive the magnitude of the constraint violation for each linear constraint.\n- **sum**: is a variable to receive the sum of the constraint violations over all the constraints.\n- **selected**: is an array identifying the selected solution.\n- **seg**: is the segment of the solution to which the linear constraints apply.\n- **child**: is an optional parameter, and should be specified only when EvaluateLC is called from a user crossover operator.\n\nThe EvaluateLC routine can be called from a user crossover operator, mutation operator, or objective function to determine if a solution violates linear inequality constraints of the form $Ax \\leq b$. For $n$ linear constraints in $m$ variables, the $lc$ array should have dimension $n \\times (m + 1)$. For each linear constraint $i = 1, \\ldots, n$, $lc[i, j] = A[i, j]$ for $j = 1, \\ldots, m$, and $lc[i, m + 1] = b[i]$. The $results$ array should be one-dimensional with size $n$. The EvaluateLC call fills in the elements of $results$ such that\n\n$$results[i] = \\begin{cases} \n0, & \\text{if } \\sum_{j=1}^{m} A[i,j]x[j] \\leq b[i] \\\\\n\\sum_{j=1}^{m} A[i,j]x[j] - b[i], & \\text{otherwise}\n\\end{cases}$$\n\nIn the variable **sum**, the EvaluateLC call returns the value $\\sum_{i=1}^{n} results[i]$. Note that **sum** $\\geq 0$, and **sum** = 0 implies that no constraints are violated. When you call EvaluateLC from your user routine, the **selected** parameter of the EvaluateLC call must be the same as the first parameter passed to your user routine to properly identify the solution to be checked. The **seg** parameter identifies which segment of the solution\nshould be checked. Real, integer, or Boolean encodings can be checked with this routine. If EvaluateLC is called from a user crossover operator, the child parameter must be specified to indicate which offspring is to be checked. The value child = 1 requests the first offspring, child = 2 requests the second, and so on.\n\n---\n\nGetDimensions Call\n\ncall GetDimensions ( source, dest ) ;\n\nThe GetDimensions call gets the dimensions of an array variable. The inputs to the GetDimensions subroutine are as follows:\n\n- source is the array variable whose dimensions are desired.\n- dest is an array to receive the dimensions of source.\n\nThe GetDimensions subroutine is used to get the dimensions of an array passed into a user subroutine. The input dest should be an array of one dimension, with at least as many elements as there are dimensions in source (a maximum of 6). Any extra elements in dest are filled with zeros.\n\n---\n\nGetObjValues Call\n\ncall GetObjValues ( dest, n ) ;\n\nThe GetObjValues call retrieves objective function values from the current solution generation. The inputs to the GetObjValues subroutine are as follows:\n\n- dest is an array to receive the objective values.\n- n is the number of objective values to get.\n\nThe GetObjValues subroutine is used to retrieve the objective values for the current solution generation. It can be called from a user update routine or finalize routine. If it is called from a finalize routine, and if the elite parameter from a SetElite call is 1 or greater, then the first elite members of the population are the fittest of the population, and they are sorted in order, starting with the most fit. The input dest should be a dimensioned variable, with dimension greater than or equal to n.\n\n---\n\nGetSolutions Call\n\ncall GetSolutions ( sol, n, seg ) ;\n\nThe GetSolutions call retrieves solutions from the current generation. The inputs to the GetSolutions subroutine are as follows:\n\n- sol is an array to receive the solution elements.\n- n is the number of solutions to get.\n- seg is the segment of the solution to retrieve.\n\nThe GetSolutions subroutine is used to retrieve solutions from the current generation. You would normally call it from an update or finalize subroutine for post processing or analysis. If the elite parameter has been set with a SetElite call, then the first elite members of the population are the fittest, and they are sorted.\nChapter 4: The GA Procedure\n\nin order, starting with the most fit. The sol variable should have two dimensions, with the first dimension representing the solution number, and the second representing the element within the solution. For example, if the encoding of the problem was I10, then \\( \\text{sol}[2, 3] \\) would be the value of the third element of the second solution in the current population. For real, integer, Boolean, and sequence encoding, each solution element is mapped to the corresponding element of the sol array. The seg parameter specifies the solution segment desired. For example, if the encoding was set in the SetEncoding call to ‘R10I5’, then segment 1 is R10 and segment 2 is I5.\n\n### Initialize Call\n\n```\ncall Initialize ( option, size < , option, size > . . . ) ;\n```\n\nThe Initialize call creates the initial solution generation. The inputs to the Initialize subroutine are as follows:\n\n- **option** is a string that specifies an initialization option.\n- **size** is the number of solutions to create by using a given option.\n\nThe Initialize subroutine must be called to create the first solution generation, and can be used to reinitialize a solution population during the optimization process. The available options and their effect are as follows:\n\n- **‘_uniform_’** generate uniformly distributed solutions —for integer and real encoded segments for which SetBounds has been called, segment elements will be uniformly distributed between the upper and lower bounds. If no bounds have been specified for an integer or real encoded segment, then the elements will be set to 0. For Boolean encoded segments the elements will be randomly assigned 0 or 1, and for sequence encoded segments random sequences will be generated.\n\n- **‘_dataset_’** read solutions from the data set specified in a FIRSTGEN= option. If the data set has more observations than requested, the extra observations are ignored.\n\n- **‘default’** read solutions from the data set specified in a FIRSTGEN= option, if one was specified. If none was specified or the data set has fewer observations than requested, fill in the remaining solution population by using the ‘_uniform_’ option.\n\n- **‘_retain_’** bring forward the best solutions from the current generation. This option cannot be used for the first initialization.\n\n- **‘user-routine’** Any string not matching the preceding options is interpreted to be a user-defined initialization routine. See the section “Defining a User Initialization Routine” on page 131 for information about defining an initialization subroutine.\n\nAfter the Initialize call, the current solution population size is the sum of the population sizes specified for each option. The following rules also apply to the option specifications:\n\n1. All options must be literal quoted strings.\n2. No option type can be specified more than once in the same Initialize call. No more than one user initialization routine can be specified.\n\n3. ‘default’ cannot be specified in combination with the ‘_uniform_’ or ‘_dataset_’ options.\n\n4. If the ‘_uniform_’ option is specified, the solution encoding must include at least one segment that is either Boolean or sequential, or that has bounds specified with a SetBounds call.\n\nMarkPareto Call\n\ncall MarkPareto (result, n, objectives, minmax ) ;\n\nThe MarkPareto call identifies the Pareto-optimal set from a population of solutions. The inputs to the MarkPareto call are as follows:\n\n- **result** is a one-dimensional array to accept the results of the evaluation. Its size should be the same as the size of the population being evaluated; \\( \\text{result}[i] = 1 \\) if solution \\( i \\) is Pareto optimal, and 0 otherwise.\n\n- **n** is a variable to receive the number of Pareto-optimal solutions.\n\n- **objectives** is a two-dimensional array that contains the multiple objective values for each solution. It should be dimensioned \\( [p, q] \\), where \\( p \\) is the size of the population, and \\( q \\) is greater than or equal to the number of objectives to be considered.\n\n- **minmax** is a one-dimensional array to specify how the objective values are to be used. It should be of size \\( q \\), where \\( q \\) is greater than or equal to the number of objectives to be considered. \\( \\text{minmax}[k] = -1 \\) if objective \\( k \\) is to be minimized, \\( \\text{minmax}[k] = 1 \\) if objective \\( k \\) is to be maximized, \\( \\text{minmax}[k] = 0 \\) if objective \\( k \\) is not to be considered, and \\( \\text{minmax}[k] = -2 \\) designates an objective that prevents the member from being considered for Pareto optimality if it is nonzero.\n\nThe MarkPareto call is used to identify the Pareto-optimal subset from a population of solutions. See the section “Optimizing Multiple Objectives” on page 135 for a full discussion of Pareto optimality. MarkPareto can be called from a user update routine, which is called after the individual solution objective values have been calculated and before selection takes place. To make best use of this routine, in your encoding you need to set up a segment to record all the objective values you intend to use in the Pareto-optimal set evaluation. In a user objective function, you should calculate the multiple objectives and write them to the chosen segment. In an update routine (designated with a SetUpdateRoutine call), you can use a GetSolutions call to retrieve these segments, and then pass them to a MarkPareto call. The following statements show how this could be done:\n\n```\nsubroutine update(popsize);\n\n array objectives[1,1] /nosym;\n call dynamic_array(objectives, popsize, 3);\n\n array pareto[1] /nosym;\n```\ncall dynamic_array(pareto, popsize);\n\narray minmax[3] /nosym (1 -1 0);\n\ncall GetSolutions(objectives, popsize, 2);\n\ncall MarkPareto(pareto, npareto, objectives, minmax);\n\ndo i = 1 to popsize;\n objectives[i,3] = pareto[i];\nend;\n\ncall UpdateSolutions(objectives, popsize, 2);\n\ncall SetElite(npareto);\n\nendsub;\n\nThis is an example of a user update routine that might be used in a multiobjective optimization problem. It is assumed that a user objective function has calculated two different objectives and placed their values in the first two elements of segment 2 of the problem encoding. The first objective is to be maximized, and the second is to be minimized. Segment 2 has three elements, and the third element is used to mark the Pareto-optimal solutions. After dynamically allocating the necessary arrays from the popsize (population size) parameter, the update routine first retrieves the current solutions into the objectives array with the GetSolutions call. It then passes the objectives array directly to the MarkPareto call to perform the Pareto-optimal evaluations. Note that the minmax array directs the MarkPareto call to maximize the first element, minimize the second, and ignore the third. After the MarkPareto call, the update routine writes the results back to the third element of the objectives array and writes the objectives array back to the solution population with the UpdateSolutions call. This marks the solutions that compose the Pareto-optimal set. The update routine then sets the elite parameter equal to the number of Pareto-optimal solutions with the SetElite call. It is assumed that the user has provided a fitness comparison function (designated with a SetCompareRoutine call) that always selects a Pareto-optimal solution over a non-Pareto-optimal one, so the elite setting guarantees that all the Pareto-optimal solutions are retained from generation to generation. Example 4.3 illustrates the use of the MarkPareto call.\n\n**Mutate Call**\n\n```\ncall Mutate( selected, seg, type<, parameter1, parameter2, ... > ) ;\n```\n\nThe Mutate call executes a genetic mutation operator from within a user subroutine. The inputs to the subroutine are as follows:\n\n- **selected** is an array that specifies the solution to be mutated.\n- **seg** is the desired segment of the solution to which the mutation should be applied.\n- **type** is the type of mutation operator to apply, which also determines the number and type of parameters expected.\n\n- **parameter1-n** are optional parameters applicable to some operators.\nThe accepted values for \\textit{type} and the corresponding parameters are summarized in Table 4.3.\n\n\\begin{table}[h]\n\\centering\n\\caption{Mutation Operator Types}\n\\begin{tabular}{|l|l|l|}\n\\hline\n\\textbf{Type} & \\textbf{Encodings} & \\textbf{Parameters} \\\\\n\\hline\n‘delta’ & real, integer & \\textit{delta} \\\\\n& & \\textit{n} \\\\\n‘invert’ & sequence & \\\\\n‘swap’ & sequence & \\textit{n} \\\\\n‘uniform’ & real, integer, Boolean & \\textit{np} \\\\\n\\hline\n\\end{tabular}\n\\end{table}\n\nThe parameters are as follows:\n\n- \\textit{delta} is a vector of delta values for each component of the solution, used only for the Delta mutation operator.\n- \\textit{n} specifies the number of solution elements that should be mutated for the Delta operator, and the number of swaps that should be made for the Swap operator.\n- \\textit{np} specifies the number of solution elements that should be mutated, if \\textit{np} is integer; specifies the mutation probability for each solution element if $0 < \\textit{np} < 1$.\n\nThe Mutate call should be made only from within a user mutation subroutine. The precise action of these mutation operators is described in the section “Mutation Operators” on page 122.\n\n---\n\n**Objective Function**\n\n\\[ r = \\text{Objective} \\left( \\text{selected, seg, type}, \\text{parameter1, parameter2, . . .} \\right); \\]\n\nThe Objective call evaluates a standard objective function from within a user subroutine. The inputs to the function are as follows:\n\n- \\textit{selected} is an array that specifies the solution to be evaluated.\n- \\textit{seg} is the desired segment of the solution to be evaluated.\n- \\textit{type} is objective function name, which also determines the number and type of parameters expected.\n- \\textit{parameter1-n} are optional parameters applicable to particular objective functions.\n\nThe accepted values for \\textit{type} and the corresponding parameters are summarized in Table 4.4.\n\n\\begin{table}[h]\n\\centering\n\\caption{Objective Function Types}\n\\begin{tabular}{|l|l|l|}\n\\hline\n\\textbf{type} & \\textbf{encodings} & \\textbf{parameters} \\\\\n\\hline\n‘TSP’ & sequence & \\textit{distances} \\\\\n\\hline\n\\end{tabular}\n\\end{table}\nChapter 4: The GA Procedure\n\nThe parameters are as follows:\n\n\\[ \\textit{distances} \\] is a matrix of distances between locations, such that \\[ \\textit{distances}[i, j] \\] is the distance between location \\( i \\) and \\( j \\).\n\nThe Objective call should be made only from within a user objective function. The precise actions of the standard objective functions are described in the section “Objective Functions” on page 124.\n\n---\n\n**PackBits Call**\n\n\\[ \\text{call PackBits (array, start, width, value);} \\]\n\nThe PackBits call writes bits to a packed integer array. The inputs to the PackBits subroutine are as follows:\n\n- \\( \\textit{array} \\) is an array to which the value is to be assigned.\n- \\( \\textit{start} \\) is the starting position for the bit assignments.\n- \\( \\textit{width} \\) is the number of bits to assign.\n- \\( \\textit{value} \\) is the value to be assigned to the bits. For a single bit, this should be 0 or 1.\n\nThe PackBits subroutine facilitates the assignment of bit values into an integer array, effectively using the integer array as an array of bits. One common use for this routine is within a user genetic operator subroutine to pack bit values into an integer vector solution segment. The bit values assigned with the PackBits call can be retrieved with the UnpackBits function.\n\nThe \\( \\textit{start} \\) parameter is the lowest desired bit position in the bit vector, where the least significant bit of \\( \\textit{value} \\) is to be stored. The \\( \\textit{start} \\) parameter can range in value from 1 to \\( \\textit{maxbits} \\), where \\( \\textit{maxbits} \\) is the product of 32 times the number of elements in the integer array.\n\nThe \\( \\textit{width} \\) parameter is the number of bits of \\( \\textit{value} \\) to be stored. It is bounded by \\( 0 < \\textit{width} < (\\textit{maxbits} - \\textit{start} + 1) \\) and must also not exceed 32.\n\nBits not within the range defined by \\( \\textit{start} \\) and \\( \\textit{width} \\) are not changed. If the magnitude of \\( \\textit{value} \\) is too large to express in \\( \\textit{width} \\) bits, then the \\( \\textit{width} \\) least significant bits of \\( \\textit{value} \\) are transferred. The following program fragment, which might occur in a mutation subroutine, first reads a selected solution segment into \\( s \\) with the ReadMember call and then overwrites the first and second least significant bits of the solution with ones before writing it back to the current generation.\n\n\\[\n\\begin{align*}\n\\text{array } s[2];\n\\text{call ReadMember(selected, seg, s);} \\\\\n\\ldots \\\\\n/* \\text{interposing code} */ \\\\\n\\ldots \\\\\n\\text{call PackBits(s, 1, 2, 3); /* start = 1, width = 2,}\n\\quad \\text{* value = 3 = binary 11}\n\\quad */ \\\\\n\\text{call WriteMember(selected, seg, s);} \n\\end{align*}\n\\]\nProgramming Statements\n\nThis section lists the programming statements used to initialize the model, code the objective function, and control the optimization process in the GA procedure. It documents the differences between programming statements in the GA procedure and programming statements in the DATA step. The syntax of programming statements used in PROC GA is identical to that of programming statements used in the FCMP procedure.\n\nMost of the programming statements that can be used in the SAS DATA step can also be used in the GA procedure. See the SAS Statements: Reference or BASE SAS documentation for a description of the SAS programming statements.\n\n```\nvariable = expression;\nvariable + expression;\narrayvar[substring] = expression;\nABORT;\nCALL subroutine < ( parameter-1 <, ...parameter-n > ) >;\nDELETE;\nDO program-statements; END;\nDO variable = expression TO expression <BY expression>;\n program-statements; END;\nDO WHILE expression;\n program-statements; END;\nDO UNTIL expression;\n program-statements; END;\nGOTO statement_label;\nIF expression THEN program-statement;\n <ELSE program-statement>;\nPUT <variable(s)> @@; \nRETURN <expression>;\nSELECT <(select-expression)>;\n WHEN-1 (expression-1 <…expression-n>)program-statement ;\n <WHEN-n (expression-1 <…expression-n>)program-statement >\n <OTHERWISE program-statement >\nSTOP;\nSUBSTR( variable, index, length ) = expression;\n```\n\nFor the most part, the SAS programming statements work as they do in the SAS DATA step as documented in the SAS Statements: Reference. However, there are several differences that should be noted.\n\n- The ABORT statement does not permit any arguments.\n- The DO statement does not permit a character index variable. Thus\n\n ```\ndo i = 1,2,3;\n \n do i = ’A’,’B’,’C’;\n ```\n\n is not.\n• The PUT statement, used mostly for program debugging in PROC GA, supports only some of the features of the DATA step PUT statement, and has some new features that the DATA step PUT statement does not:\n\n – The PROC GA PUT statement does not support line pointers, factored lists, iteration factors, overprinting, _INFILE_, the colon (:) format modifier, or “$”.\n – The PROC GA PUT statement does support expressions, but the expression must be enclosed inside parentheses. For example, the following statement displays the square root of x: put (sqrt(x));\n – The PROC GA PUT statement permits an array name without subscripts. The statement PUT A; prints all the elements of array A. The statement PUT A=; prints the elements of array A with each value labeled with the name of the element variable.\n – The PROC GA PUT statement supports the print item _PDV_ to print a formatted listing of all variables in the program. For example, the following statement displays a more readable listing of the variables than the _all_ print item: put _pdv_;\n\n• The WHEN and OTHERWISE statements permit more than one target statement. That is, DO/END groups are not necessary for multiple-statement WHENs. For example, the following syntax is valid:\n\n SELECT;\n WHEN ( exp1 ) stmt1;\n stmt2;\n WHEN ( exp2 ) stmt3;\n stmt4;\n END;\n\n---\n\n**ReadChild Call**\n\n```call ReadChild ( selected, seg, n, values ) ;```\n\nThe ReadChild call reads a segment from a selected child solution into an array, within a user crossover operator. The inputs to the ReadChild subroutine are as follows:\n\n- `selected` specifies the family (parents and children) obtained from the selection process.\n- `seg` specifies the solution segment to be read.\n- `n` specifies the child in the family from which to read the solution segment.\n- `values` specifies an array to receive the solution elements.\n\nThe ReadChild call is used to obtain the solution values for manipulation within a user crossover operator subroutine. Normally it is needed only if you need to augment the action of a GA procedure-supplied crossover operator. You might need to make modifications to satisfy constraints, for example. The `selected` parameter is passed into the user subroutine by the GA procedure. The `seg` parameter is the desired segment of the solution to be obtained. Segments, which correspond to different encodings in the encoding string, are numbered, starting from 1 as the first segment. The parameter `n` should be 1 to get the first child and 2 for the second. The parameter `values` is an array, which should be dimensioned large enough to contain the segment’s\nencoding. For example, the following subroutine illustrates how you could use the Read/WriteChild calls to modify offspring generated with a standard genetic operator:\n\n```plaintext\ncall SetEncoding('R5');\n\nsubroutine cross(selected[*]);\n\n /* generate offspring with arithmetic crossover operator */\n call CrossArithmetic(selected, 1); /* here 1 refers to segment 1*/\n\n array child1[5];\n array child2[5];\n\n /* get elements of first child solution */\n call ReadChild(selected, 1, 1, child1);\n\n /* get elements of second child solution values */\n call ReadChild(selected, 1, 2, child2);\n\n ...\n\n /* code to modify elements in child1 and child2 */\n ...\n\n call WriteChild(selected,1,1,child1);\n call WriteChild(selected,1,2,child2);\n```\n\n---\n\n**ReadCompare Call**\n\n```plaintext\ncall ReadCompare ( selected, seg, n, values );\n```\n\nThe ReadCompare call reads a segment from a selected solution into an array, within a user fitness comparison subroutine. The inputs to the ReadCompare subroutine are as follows:\n\n- **selected**: specifies the pair of solutions to be compared, obtained from the selection process.\n- **seg**: specifies the solution segment to be read.\n- **n**: specifies the solution (1 or 2) from which to read the segment.\n- **values**: specifies an array to receive the solution elements.\n\nThe ReadCompare call is used to obtain the solution values for manipulation within a user fitness comparison subroutine, which can be designated in a **SetCompareRoutine call**.\n\n---\n\n**ReadMember Call**\n\n```plaintext\ncall ReadMember ( selected, seg, destination );\n```\n\nThe ReadMember call reads the selected solution into an array for a user objective function or mutation operator.\nThe inputs to the ReadMember subroutine are as follows:\n\n- **selected**: is a parameter passed to the user subroutine by the GA procedure, which points to the selected solution.\n- **seg**: specifies which segment of the solution to retrieve.\n- **destination**: specifies an array in which to store the solution elements.\n\nThe ReadMember call is used within a user objective function or mutation operator to obtain the elements of a selected solution and write them into a specified vector. They can then be used to compute an objective value, or in the case of a mutation operator, manipulated and written back out with a WriteMember call.\n\n---\n\n### ReadParent Call\n\n```\ncall ReadParent ( selected, seg, n, destination ) ;\n```\n\nThe ReadParent call reads selected solution elements into an array in a user crossover subroutine. The inputs to the ReadParent subroutine are as follows:\n\n- **selected**: is a parameter passed to the user subroutine by the GA procedure, which points to the selected solution family.\n- **seg**: is the segment of the desired parent solution to be obtained.\n- **n**: is the number of the parent, starting at 1.\n- **destination**: is an array in which to store the solution elements.\n\nThe ReadParent subroutine is called inside a user crossover operator subroutine to obtain the elements of selected parent solutions. Normally you would then manipulate and combine the elements of the two parents and use a WriteChild call to create the child offspring and complete the action of the crossover operator.\n\n---\n\n### ReEvaluate Call\n\n```\ncall ReEvaluate ( <index> ) ;\n```\n\nThe ReEvaluate call reruns the evaluation phase of the genetic algorithm. The inputs to the ReEvaluate subroutine are as follows:\n\n- **index**: is a numeric scalar or array that specifies the indices of the solutions to be updated. The indices correspond to the order of the solutions obtained from a GetSolutions call.\n\nThe ReEvaluate call recomputes the objective values for the current generation. You do not normally need to use this call, because the GA procedure evaluates the objective function during the optimization process in the evaluation phase. This subroutine should be called from a user update or finalize routine if a parameter that affects the objective value or solution is changed. The optional **index** parameter enables you to restrict the recomputation to the solution or subset of solutions specified. If the **index** parameter is not supplied, then the objective values of all the solutions will be recomputed.\n\nFor example, you might have a user objective function that can perform an additional local optimization if a particular parameter is set. If your update routine changes that parameter, then you should call the ReEvaluate subroutine to update the solutions and objective function values.\nSetBounds Call\n\n\\[\n\\text{call SetBounds ( lower, upper <, seg> );}\n\\]\n\nThe SetBounds call sets constant upper and lower bounds. The inputs to the SetBounds subroutine are as follows:\n\n- \\(\\text{lower}\\) is a lower bound for the solution components.\n- \\(\\text{upper}\\) is an upper bound for the solution components.\n- \\(\\text{seg}\\) is optional, and specifies a segment of the solution to which the bounds apply. If \\(\\text{seg}\\) is not specified, then it defaults to a value of 1.\n\nThe SetBounds subroutine is used to establish upper and lower bounds on the solution space. It applies only to integer and real encoding. For multiple segment encoding, use the \\(\\text{seg}\\) parameter to specify a segment other than the first. \\(\\text{upper}\\) and \\(\\text{lower}\\) must be arrays, with the same dimension as the encoding size. SetBounds must be called for all integer or real encoded segments to which you apply the Uniform mutation operator. The action of the standard mutation and crossover operators supplied by the GA procedure is automatically modified so that the bounds established by a SetBounds call are respected. For an integer encoded segment, only integer values are allowed for the upper and lower bounds.\n\nSetCompareRoutine Call\n\n\\[\n\\text{call SetCompareRoutine ( 'routine' );}\n\\]\n\nThe SetCompareRoutine call installs a user function to compare the fitness of solutions. The input to the SetCompareRoutine subroutine is as follows:\n\n- \\(\\text{routine}\\) is the name of a function you have defined, which is called when necessary to compare the fitness of solutions. This parameter must be a string literal; a variable is not accepted.\n\nThe SetCompareRoutine call enables you to designate a function you have defined to be used in the selection process when comparing the fitness of two solutions. The selector options that involve ranking solutions by fitness, including tournament and duel selection, will use the designated function instead of comparing the objective values directly. If the SetCompareRoutine is not called, or if it is called with an input value of ‘default’, then the objective function value will be used to compare solution fitness. The SetCompareRoutine call provides you with a way to factor multiple fitness criteria into the selection process. See the section “Defining a User Fitness Comparison Routine” on page 124 for a full description of how the fitness comparison routine should be structured and what it should return. You can use this feature to implement multiobjective optimization and other advanced optimization strategies.\n\nSetCross Call\n\n\\[\n\\text{call SetCross ( type<, seg><, pname, pvalue><, pname, pvalue>... );}\n\\]\n\nThe SetCross call sets the crossover operator. The inputs to the SetCross subroutine are as follows:\nChapter 4: The GA Procedure\n\nThe GA Procedure\n\n**type** is the name of the crossover operator to be applied.\n\n**seg** is optional, and specifies a segment of the solution to which the operator should be applied. If **seg** is not specified, then it defaults to a value of 1. **seg** needs to be specified only if multisegment encoding is used.\n\n**pname** is optional, and specifies the name of a particular property to be set for the crossover operator.\n\n**pvalue** specifies the value to be assigned to the corresponding property name.\n\nThe SetCross routine is used to assign a standard crossover operator. For multisegment encoding, the operator can be assigned to a particular solution segment with the **seg** parameter; otherwise a default segment of 1 is assumed. You can set different crossover operators for different segments with multiple SetCross calls. When a crossover event occurs, all segments in the parent solutions for which a crossover operator has been designated will undergo crossover. If more than one SetCross call is made for the same segment, then the last call nullifies any previous call for that segment. Also, a **SetCrossRoutine** call nullifies all previous SetCross calls, and a SetCross call nullifies a previous **SetCrossRoutine** call. Properties for the chosen crossover operator can be set with optional **pname-pvalue** pairs. It is also possible to set or reset operator properties with a **SetProperty** call.\n\nThe accepted values for **type** and the corresponding properties are summarized in Table 4.5. See the section “Crossover Operators” on page 116 for a full description of the available operators.\n\n<table>\n<thead>\n<tr>\n<th>type</th>\n<th>encodings</th>\n<th>properties</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>‘arithmetic’</td>\n<td>real, integer</td>\n<td>‘alpha’</td>\n</tr>\n<tr>\n<td>‘cycle’</td>\n<td>sequence</td>\n<td></td>\n</tr>\n<tr>\n<td>‘heuristic’</td>\n<td>real</td>\n<td>‘alpha’</td>\n</tr>\n<tr>\n<td>‘order’</td>\n<td>sequence</td>\n<td></td>\n</tr>\n<tr>\n<td>‘pmatch’</td>\n<td>sequence</td>\n<td></td>\n</tr>\n<tr>\n<td>‘simple’</td>\n<td>real, integer, Boolean</td>\n<td>‘alpha’, ‘p’</td>\n</tr>\n<tr>\n<td>‘twopoint’</td>\n<td>real, integer, Boolean</td>\n<td>‘alpha’</td>\n</tr>\n<tr>\n<td>‘uniform’</td>\n<td>real, integer, Boolean</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**Table 4.5** Crossover Operator Types and Properties\n\nSetCrossProb Call\n\n```call SetCrossProb (p);```\n\nThe SetCrossProb call sets the crossover probability. The input to the SetCrossProb subroutine is as follows:\n\n**p** is the crossover probability.\n\nThe SetCrossProb subroutine is used to set the crossover probability for the genetic algorithm optimization process. The crossover probability **p** should be between 0 and 1. Typical values for this parameter range from 0.6 to 1.0. The crossover probability will be overridden if required by a **SetElite** call. The elite solutions are passed on to the next generation without undergoing crossover, regardless of the crossover probability.\nSetCrossRoutine Call\n\ncall SetCrossRoutine( 'routine', nparents, nchildren );\n\nThe SetCrossRoutine call installs a user subroutine for the crossover operator. The inputs to the SetCrossRoutine subroutine are as follows:\n\n- routine: is the name of a subroutine you have defined, which is called when the mutation operator is applied. This parameter must be a string literal; a variable is not accepted.\n- nparents: is optional, and specifies the number of parent solutions the operator requires. If not specified, 2 is assumed.\n- nchildren: is optional, and specifies the number of children solutions the operator will generate. If not specified, 2 is assumed.\n\nSetElite Call\n\ncall SetElite( elite );\n\nThe SetElite call sets the number of best solutions to pass to the next generation. The input to the SetElite subroutine is as follows:\n\n- elite: is the number of best solutions to be passed unmodified from the current solution generation to the next.\n\nThe SetElite subroutine is used to ensure that the best solutions encountered in the optimization are not lost by the random selection process. In pure tournament selection, although better solutions are more likely to be selected, it is also possible that any given solution will not be chosen to participate in a tournament, and even if it is selected, it might be modified by crossover or mutation. The SetElite call modifies the optimization process such that the best elite solutions in the current population are exactly preserved and passed on to the next generation. This behavior is observed regardless of the crossover or mutation settings. When a SetElite call is made, the first elite solutions in the population retrieved by a GetSolutions call or output to a data set are the fittest, and these elite solutions are sorted so that the most fit is first. In general, using the SetElite call speeds the convergence of the optimization process. However, it can also lead to premature convergence before a true global optimum is reached. If no SetElite call is made, a default elite value of 1 is used by the GA procedure to make sure that the best solution encountered in the optimization process is never lost.\n\nSetEncoding Call\n\ncall SetEncoding( encoding );\n\nThe SetEncoding call specifies the problem encoding. The input to the SetEncoding subroutine is as follows:\n\n- encoding: is a string used to specify the form of the solution.\n\nThe SetEncoding subroutine is used to establish the type of problem solution encoding. The encoding parameter should be a string of letter-number pairs, where the letter determines the type of encoding: I for integer, R for real-valued, S for sequences, and B for Boolean values. Each letter is followed by a number to indicate the number of components for that encoding. Multiple letter-number pairs can be used to\nspecify a multisegment encoding. For example, the following call specifies that solutions be in the form of a 10-member integer vector:\n\n\\[\n\\text{call SetEncoding('I10');}\n\\]\n\nThe following call specifies that solutions have a 5-component integer segment and a 10-component real-valued segment:\n\n\\[\n\\text{call SetEncoding('I5R10');}\n\\]\n\nSee the section “Using Multisegment Encoding” on page 115 for details about using multisegment encoding.\n\n---\n\n**SetFinalize Call**\n\n\\[\n\\text{call SetFinalize('routine');}\n\\]\n\nThe SetFinalize call designates a user subroutine to perform post processing at the end of the optimization process. The input to the SetFinalize subroutine is as follows:\n\n- **routine** is the name of a subroutine you have defined, which is called when the optimization process ends. This parameter must be a string literal; a variable is not accepted.\n\nThe SetFinalize subroutine enables you to define a subroutine to be called at the end of the optimization process. You might use this subroutine to perform additional refinements of the best solution, or you could generate and write out additional data for plots or reports.\n\n---\n\n**SetMut Call**\n\n\\[\n\\text{call SetMut type<, seg><, pname, pvalue><, pname, pvalue>...);}\n\\]\n\nThe SetMut call sets the mutation operator. The inputs to the SetMut subroutine are as follows:\n\n- **type** is the name of the mutation operator to be applied.\n- **seg** is optional, and specifies a segment of the solution to which the operator should be applied. If **seg** is not specified, then it defaults to a value of 1. **seg** needs to be specified only if multisegment encoding is used.\n- **pname** is optional, and specifies the name of a particular property to be set for the mutation operator.\n- **pvalue** specifies the value to be assigned to the corresponding property name.\n\nThe SetMut routine is used to assign a standard mutation operator. For multisegment encoding, the operator can be assigned to a particular solution segment with the **seg** parameter; otherwise a default segment of 1 is assumed. You can set different mutation operators for different segments with multiple SetMut calls.\nWhen a mutation event occurs, all the operators will applied to the same solution. If more than one SetMut call is made for the same segment, then the last call nullifies any previous call for that segment. Also, a SetMutRoutine call nullifies all previous SetMut calls, and a SetMut call nullifies a previous SetMutRoutine call. Properties for the chosen mutation operator can be set with optional \\textit{pname=pvalue} pairs. It is also possible to set or reset operator properties with a SetProperty call.\n\nThe accepted values for \\textit{type} and the corresponding properties are summarized in Table 4.6. See the section “Mutation Operators” on page 122 for a full description of the available operators.\n\n<table>\n<thead>\n<tr>\n<th>type</th>\n<th>encodings</th>\n<th>properties</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'delta'</td>\n<td>real, integer</td>\n<td>'delta'</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>'nchange'</td>\n</tr>\n<tr>\n<td>'invert'</td>\n<td>sequence</td>\n<td></td>\n</tr>\n<tr>\n<td>'null'</td>\n<td>all encodings</td>\n<td></td>\n</tr>\n<tr>\n<td>'swap'</td>\n<td>sequence</td>\n<td>'nswap'</td>\n</tr>\n<tr>\n<td>'uniform'</td>\n<td>real, integer, Boolean</td>\n<td>'nchange'</td>\n</tr>\n</tbody>\n</table>\n\n\\textbf{SetMutProb Call}\n\n\\texttt{call SetMutProb (p);\n}\n\nThe SetMutProb call sets the mutation probability. The input to the SetMutProb subroutine is as follows:\n\n\\texttt{p}\n\nis the mutation probability.\n\nThe SetMutProb subroutine is used to set the mutation probability for the genetic algorithm optimization. The probability \\texttt{p} should be a number between 0 and 1, and is interpreted as the probability that a solution in the next generation should have the mutation operator applied to it. If a SetElite call has been made, then the elite solutions do not undergo mutation. Generally, a high mutation probability degrades the convergence of the genetic algorithm optimization, but some level of mutation is required to assure a thorough search and avoid premature convergence before the global optimum is found. Typical values for \\texttt{p} are near 0.05 or less.\n\n\\textbf{SetMutRoutine Call}\n\n\\texttt{call SetMutRoutine ('routine');\n}\n\nThe SetMutRoutine call installs a user subroutine for the mutation operator. The input to the SetMutRoutine subroutine is as follows:\n\n\\texttt{routine}\n\nis the name of a subroutine you have defined, which is called when the mutation operator is applied. This parameter must be a string literal; a variable is not accepted.\n\nThe SetMutRoutine call enables you to designate a subroutine you have defined to be used for the mutation operator. Your subroutine will be called whenever the mutation operation is performed. See the section “Defining User Genetic Operators” on page 126 for more information about defining a mutation operator.\nChapter 4: The GA Procedure\n\n### SetObj Call\n\n```fortran\n call SetObj ( type, minmax, seg<seg>, pname, pvalue<, pname, pvalue>...) ;\n```\n\nThe SetObj call sets the objective function. The inputs to the SetObj subroutine are as follows:\n\n- **type**: is the name of the objective function to be used.\n- **minmax**: is an indicator to maximize or minimize the objective. A value of 0 is used to specify a minimization, and a value of 1 to specify maximizing the objective.\n- **seg**: is optional, and specifies a segment of the solution to which the objective function should be applied. If `seg` is not specified, then it defaults to a value of 1. *seg* needs to be specified only if multisegment encoding is used.\n- **pname**: is optional, and specifies the name of a particular property to be set for the objective function.\n- **pvalue**: specifies the value to be assigned to the corresponding property name.\n\nThe SetObj routine is used to assign a procedure-supplied objective function. For multisegment encoding, the objective can be assigned to a particular solution segment with the *seg* parameter; otherwise a default segment of 1 is assumed. If more than one SetObj call is made, then the last call nullifies any previous call. Also, a SetObjFunc call nullifies all previous SetObj calls, and a SetObj call nullifies a previous SetObjFunc call. Properties for the chosen objective can be set with optional `pname-pvalue` pairs. It is also possible to set or reset objective properties with a SetProperty call.\n\nThe accepted values for *type* and the corresponding properties are summarized in Table 4.7. See the section “Objective Functions” on page 124 for a full description of the available objectives.\n\n### Table 4.7 Objective Function Types and Properties\n\n<table>\n<thead>\n<tr>\n<th>type</th>\n<th>encodings</th>\n<th>properties</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>‘TSP’</td>\n<td>real, integer</td>\n<td>‘distances’</td>\n</tr>\n</tbody>\n</table>\n\n### SetObjFunc Call\n\n```fortran\n call SetObjFunc ( 'fname', minmax ) ;\n```\n\nThe SetObjFunc call sets the objective to a user-defined function. The inputs to the SetObjFunc subroutine are as follows:\n\n- **fname**: is the name of a user objective function. This parameter must be a literal string.\n- **minmax**: is set to 0 to minimize the objective, 1 to maximize.\n\nThe SetObjFunc subroutine is used to designate a user function to be the objective for the optimization process. The SetObjFunc call accepts a literal string only for the function name; you cannot use a variable or expression. See the section “Defining an Objective Function” on page 130 for more information about\ndefining your own objective function. If multiple SetObjFunc calls are made, only the last one is in effect; the last call nullifies any previous SetObjFunc or SetObj calls.\n\n**SetProperty Call**\n\n```c\ncall SetProperty ( optype<, seg>, pname, pvalue<, pname, pvalue>...) ;\n```\n\nThe SetProperty call modifies properties of genetic operators, objective functions, and selectors. The inputs to the SetProperty subroutine are as follows:\n\n- **optype** is the type of operator. It should have a value of ‘cross’ for a crossover operator, ‘mut’ for a mutation operator, ‘obj’ for an objective function, or ‘sel’ for a selector.\n- **seg** is optional, used only for mutation and crossover operators, and specifies the segment in which the operator resides. It is necessary only for multisegment encoding. The default value if seg is not specified is 1.\n- **pname** specifies the name of a particular property to be set.\n- **pvalue** specifies the value to be assigned to the corresponding property name. Multiple property name-value pairs can be supplied in a SetProperty call.\n\nThe SetProperty call is used to set or modify properties of a genetic operator, objective function, or a selector. It can be called anytime during the optimization process to dynamically adapt optimization parameters. For example, you might call SetProperty from a user update routine to reduce the magnitude of the delta vector of a delta mutation operator as the optimization progresses to an optimum.\n\n**SetSel Call**\n\n```c\ncall SetSel ( selector<, pname, pvalue><, pname, pvalue>...) ;\n```\n\nThe SetSel call sets the selection parameters. The inputs to the SetSel subroutine are as follows:\n\n- **selector** is the type of selection strategy to be used.\n- **pname** is optional, and specifies the name of a particular property to be set for the selector operator.\n- **pvalue** specifies the value to be assigned to the corresponding property name.\n\nThe SetSel call is used to specify a selector for the regeneration process, which selects members of the current generation to be propagated to the next. Generally, selection is based on solution fitness, with the fittest solutions more likely to be selected.\n\nThe supported values for selector and the corresponding selector properties and their default values are summarized in Table 4.8. See the section “Specifying the Selection Strategy” on page 132 for a full description of the available selectors and their properties.\nTable 4.8 Selectors and Properties\n\n<table>\n<thead>\n<tr>\n<th>Selector</th>\n<th>Properties</th>\n<th>Default values</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'tournament'</td>\n<td>'size'</td>\n<td>2</td>\n</tr>\n<tr>\n<td>'duel'</td>\n<td>'pbest'</td>\n<td>0.8</td>\n</tr>\n</tbody>\n</table>\n\nSetUpdateRoutine Call\n\n```\ncall SetUpdateRoutine ( 'routine' );\n```\n\nThe SetUpdateRoutine call designates a control subroutine to be called at each iteration. The input to the SetUpdateRoutine subroutine is as follows:\n\n- **routine** is the name of a subroutine you have defined that is called once during each iteration of the optimization process. This parameter must be a string literal; a variable is not accepted.\n\nThe SetUpdate subroutine enables you to define a subroutine to be called at each iteration of the optimization process, in order to monitor the progress of the genetic algorithm, adjust optimization parameters, or perform calculations that depend on the population as a whole. The specified routine is called once at each iteration, just before the selection process and after the evaluation phase. See the section “Defining a User Update Routine” on page 128 for a discussion of how an update routine might be used.\n\nShellSort Call\n\n```\ncall ShellSort ( x, <, by<, descend> > );\n```\n\nThe ShellSort call sorts a numeric array. The inputs to the ShellSort subroutine are as follows:\n\n- **x** is a one or two dimensional array to be sorted.\n- **by** is an optional numeric scalar or array that specifies the columns by which the array is to be sorted. If not specified, column 1 is the default.\n- **descend** is an optional numeric scalar or array used to specify which columns in the by parameter are to be in descending order. Any columns not specified in a descend parameter will be in ascending order.\n\nThe ShellSort subroutine sorts the x array by the columns specified in the by parameter, with the first column having highest precedence, and subsequent columns applied within the preceding by groups. Sorting will be done in ascending order for each column unless that column is also specified in the descend parameter. In general the ShellSort routine does not preserve the original order in case of ties. For example, the following statements sort an array x into ascending order with respect to the first column, and sort groups with the same first column value by descending order of third column values:\n\n```\narray x[100, 3] /nosym;\n```\nShuffle Call\n\n```fortran\narray by[2] /nosym;\nby[1] = 1;\nby[2] = 3;\ndescend = 3;\ncall ShellSort(x, by, descend);\n```\n\nShuffle Call\n\n```fortran\ncall Shuffle ( x ) ;\n```\n\nThe Shuffle call randomly reorders a numeric array. The input to the Shuffle subroutine is as follows:\n\n- `x` is a numeric array to be randomly shuffled.\n\nThe Shuffle subroutine randomly rearranges the elements of the `x` array. One example of where it might be used is in a user-supplied initialization routine, to generate a random sequence-encoded solution segment.\n\nUnpackBits Function\n\n```fortran\nr = UnpackBits ( source, start, width ) ;\n```\n\nThe UnpackBits call retrieves bit values from a packed integer array. The inputs to the UnpackBits function are as follows:\n\n- `source` is an array containing the packed bit values.\n- `start` is the starting bit, with the lowest bit starting at 1.\n- `width` is the number of bits to retrieve. A value of 1 retrieves a single bit.\n\nThe UnpackBits function facilitates the extraction of bit values from arbitrary locations in an integer array. One common use for it is to retrieve bit values from an integer solution segment in a user objective or genetic operator routine. The return value, `start`, and `width` parameters are consistent with the PackBits call, which you can use to store bit values to an integer array.\n\nThe `start` parameter is the lowest desired bit position in the bit vector, corresponding to the least significant bit of the return value. The `start` parameter can range in value from 1 to `maxbits`, where `maxbits` is the product of 32 times the number of elements in the integer array.\n\nThe `width` parameter is the number of bits to be read into the return value from the array. It is bounded by `0 < width < (maxbits – start + 1)`, and must also not exceed 32.\n\nUpdateSolutions Call\n\n```fortran\ncall UpdateSolutions ( sol, n, seg ) ;\n```\n\nThe UpdateSolutions call updates the current solution population. The inputs to the UpdateSolutions subroutine are as follows:\nChapter 4: The GA Procedure\n\n\\( sol \\) is an array containing the replacement solution elements.\n\n\\( n \\) is the number of solutions to update.\n\n\\( seg \\) is the segment of the solution to replace.\n\nThe UpdateSolutions subroutine is used to replace the values of the selected solution segment with new values computed in an update routine. The update routine can be designated in a SetUpdateRoutine call. The UpdateSolutions call is often used to implement advanced strategies such as marking Pareto-optimal sets or employing local optimizations. The \\( sol \\) parameter should have 2 dimensions. The first dimension represents the solution number, and should have a value of \\( n \\) or greater. The second dimension represents the element within the solution \\( seg \\), and should be equal to the segment size.\n\n---\n\n**WriteChild Call**\n\n\\[\n\\text{call WriteChild} ( \\text{selected, seg, n, source} ) ;\n\\]\n\nThe WriteChild call assigns values to a selected child solution from within a user crossover operator. The inputs to the WriteChild subroutine are as follows:\n\n\\( selected \\) is an array specifying the selected family of solutions. The \\( selected \\) array is normally passed into the user subroutine that calls WriteChild, and should be passed unaltered to WriteChild.\n\n\\( seg \\) is the segment to which the elements are to be written.\n\n\\( n \\) is the child within the family to which the elements are to be written. A value of 1 is for the first child, 2 for the second, and so on.\n\n\\( source \\) is an array containing the values to be written.\n\nThe WriteChild subroutine is called inside a user crossover operator subroutine to assign to the elements of a selected child solution. It is normally used to complete the action of the crossover operator.\n\n---\n\n**WriteMember Call**\n\n\\[\n\\text{call WriteMember} ( \\text{selected, seg, source} ) ;\n\\]\n\nThe WriteMember call assigns values to a selected solution from within a user objective function or mutation operator. The inputs to the WriteMember subroutine are as follows:\n\n\\( selected \\) is an array specifying the selected family of solutions. The \\( selected \\) array is normally passed into the user subroutine that calls WriteMember, and should be passed unaltered to WriteMember.\n\n\\( seg \\) is the segment to which the elements are to be written.\n\n\\( source \\) is an array containing the values to be written.\n\nThe WriteMember subroutine is called inside a user objective function or mutation operator subroutine to assign values to the elements of a selected solution. It is normally used to complete the action of the objective function or mutation operator.\nDetails: GA Procedure\n\nUsing Multisegment Encoding\n\nThe GA procedure enables you to represent problems with solutions consisting of mixed parameter types by using multisegment encoding. Solutions can contain multiple segments, where each segment is a vector of one particular parameter type. Multiple segments can also be used to store additional information you want to keep for each solution for user objective functions or genetic operators. The utility functions provided by the GA procedure give you full access to read from and write to individual solution segments you define.\n\nSegments are set up with a SetEncoding call. The input parameter to this call is a string consisting of letter-number pairs, with each pair describing the type and number of elements in one segment. The permitted letters and corresponding encodings are as follows:\n\n- **R** or **r** specifies real encoding. The elements of the solution segment are real numbers. One common problem where this encoding is used is nonlinear function optimization over the real domain.\n- **I** or **i** specifies integer encoding. The elements of the solution segment are integers. Examples of where this encoding might be used include assignment problems where the integers represent which resources are assigned to particular tasks, or problems involving real variables that are constrained to be integers.\n- **B** or **b** specifies Boolean encoding. The elements of the solution consist of binary (0 or 1) bits. This type of encoding might be used, for example, to represent variables in a variable selection problem, or inclusion of particular items in a 0/1 knapsack problem.\n- **S** or **s** specifies sequence encoding. The segment consists of randomly ordered sequences of integers ranging from 1 to the number of elements. For example, [2, 4, 5, 1, 3] is an example of S5 encoding, as is [5, 3, 2, 1, 4]. Sequence encoding is a natural way to represent routing optimizations like the traveling salesman problem, or any problem optimizing permutations of parameters.\n\nSuppose the problem is to optimize the scheduling of 20 tasks, and for each task you need to choose one machine out of a set of appropriate machines for each task. The natural encoding for that problem could be set up with the following call:\n\n```plaintext\ncall SetEncoding('I20S20');\n```\n\nThis call specifies a two-segment solution encoding, with segment 1 (I20) an integer vector representing the machine assignment for each task, and segment 2 (S20) representing the sequence of tasks.\n\nWhen you use multisegment encoding, you must specify the segment parameter in SetMut or SetCross calls to specify an operator in a segment other than the first one. If you code your own operator subroutines, you can use utility functions provided by the GA procedure to extract and write out values to individual segments of the solution, and routines provided by the GA procedure to perform standard genetic crossover and mutation operations on selected segments. See the section “Using Standard Genetic Operators and Objective Functions” on page 116 for a discussion of the operators provided by the GA procedure. See the section “Defining User Genetic Operators” on page 126 and the section “Defining an Objective Function” on page 130 for details of defining user routines.\nUsing Standard Genetic Operators and Objective Functions\n\nThe GA procedure includes a set of objective functions and crossover and mutation operators, and also enables you to define your own with a subroutine. The standard operators and objectives that are provided for each encoding type are summarized in Table 4.9.\n\n<table>\n<thead>\n<tr>\n<th>Encoding</th>\n<th>Crossover</th>\n<th>Mutation</th>\n<th>Objective</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>real</td>\n<td>arithmetic</td>\n<td>delta</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>heuristic</td>\n<td>null</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>null</td>\n<td>uniform</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>simple</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>twopoint</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>uniform</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>integer</td>\n<td>arithmetic</td>\n<td>delta</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>null</td>\n<td>null</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>simple</td>\n<td>uniform</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>twopoint</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>uniform</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Boolean</td>\n<td>simple</td>\n<td>null</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>null</td>\n<td>uniform</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>twopoint</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>uniform</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>sequence</td>\n<td>cycle</td>\n<td>invert</td>\n<td>TSP</td>\n</tr>\n<tr>\n<td></td>\n<td>null</td>\n<td>null</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>order</td>\n<td>swap</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>pmatch</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nThe following sections describe the standard genetic operators and objectives and how to invoke them.\n\nCrossover Operators\n\n*Arithmetic*\n\nThis operator is defined for real and integer encoding. It treats the solution segment as a vector, and computes offspring of parents $P$ and $Q$ as\n\n\\[\n\\text{child}_1 = aP + (1 - a)Q \\\\\n\\text{child}_2 = aQ + (1 - a)P\n\\]\n\nwhere $a$ is a random number between 0 and 1 generated by the GA procedure. For integer encoding, each component is rounded to the nearest integer. It has the advantage that it always produces feasible offspring for a convex solution space. A disadvantage of this operator is that it tends to produce offspring toward the interior of the search region, so it might not work if the optimum lies on or near the search region boundary. For single-segment encoding, you can specify the use of this operator with the call\n\n```call SetCross(‘Arithmetic’);```\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n```call SetCross( 'Arithmetic', segment );```\n\nFrom within a user crossover subroutine, you can use the call\n\n```call Cross( selected, segment, 'Arithmetic' );```\n\nwhere `selected` is the selection parameter passed to your subroutine, and `segment` is the segment to which the arithmetic crossover operator is to be applied.\n\n**Cycle**\n\nThis operator is defined for sequence encoding. It produces offspring such that the position of each element value in the offspring comes from one of the parents. For example, consider parents `P` and `Q`,\n\n\\[\nP = [1, 2, 3, 4, 5, 6, 7, 8, 9]\n\\[\nQ = [8, 7, 9, 3, 4, 1, 2, 5, 6]\n\\]\n\nFor the first child, pick the first element from the first parent:\n\n\\[\nchild1 = [1, \\ldots, \\ldots, \\ldots, \\ldots, \\ldots, \\ldots, \\ldots, \\ldots, \\ldots]\n\\]\n\nTo maintain the condition that the position of each element value must come from one of the parents, the position of the ‘8’ value must come from `P`, because the ‘8’ position in `Q` is already taken by the ‘1’ in `child1`:\n\n\\[\nchild1 = [1, \\ldots, \\ldots, \\ldots, \\ldots, \\ldots, \\ldots, 8, \\ldots]\n\\]\n\nNow the position of ‘5’ must come from `P`, and so on until the process returns to the first position:\n\n\\[\nchild1 = [1, \\ldots, 3, 4, 5, 6, 8, 9]\n\\]\n\nAt this point, choose the remaining element positions from `Q`:\n\n\\[\nchild1 = [1, 7, 3, 4, 5, 6, 2, 8, 9]\n\\]\n\nFor the second child, starting with the first element from the second parent, similar logic produces\n\n\\[\nchild2 = [8, 2, 9, 3, 4, 1, 7, 5, 6]\n\\]\n\nThis operator is most useful when the absolute position of the elements is of most importance to the objective value. For single-segment encoding, you can specify this operator with the call\n\n```call SetCross( 'Cycle' );```\n\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n```call SetCross( 'Cycle', segment );```\n\nFrom within a user crossover subroutine, you can use the use the call\n\n```call Cross( selected, segment, 'Cycle' );```\n\nwhere `selected` is the selection parameter passed to your subroutine, and `segment` is the segment to which the cycle crossover operator is to be applied.\nChapter 4: The GA Procedure\n\n**Heuristic**\n\nThis operator is defined for real encoding. It treats the solution segments as real vectors. It computes the first offspring from two parents \\( P \\) and \\( Q \\), where \\( Q \\) is the parent with the best objective value, as\n\n\\[\n\\text{child1} = a(Q - P) + Q \\\\\n\\text{child2} = aQ + (1-a)P\n\\]\n\nwhere \\( a \\) is a random number between 0 and 1 generated by the GA procedure. The first child is a projection, and the second child is a convex combination, as with the arithmetic operator. This operator is unusual in that it uses the objective value. It has the advantage of directing the search in a promising direction, and automatically fine-tuning the search in an area where solutions are clustered. If the solution space has upper and lower bound constraints, the offspring are checked against the bounds, and any component outside its bound is set equal to that bound. The heuristic operator performs best when the objective function is smooth, and might not work well if the objective function or its first derivative is discontinuous.\n\nFor single-segment encoding, you can specify this operator with the call\n\n```plaintext\ncall SetCross('Heuristic');\n```\n\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n```plaintext\ncall SetCross('Heuristic', segment);\n```\n\nFrom within a user crossover subroutine, you can use the call\n\n```plaintext\ncall Cross(selected, segment, 'Heuristic');\n```\n\nwhere `selected` is the selection parameter passed to your subroutine, and `segment` is the segment to which the heuristic crossover operator is to be applied.\n\n**Null**\n\nThis operator is used to specify that no crossover operator be applied. It is not usually necessary to specify the null operator, except when you want to cancel a previous operator selection. You can specify the null operator with the call\n\n```plaintext\ncall SetCross('null');\n```\n\nFor multisegment encoding, you can specify a segment to which the operator should be applied with the call\n\n```plaintext\ncall SetCross('null', segment);\n```\n\n**Order**\n\nThis operator is defined for sequence encoding. It produces offspring by transferring a randomly chosen subsequence of random length and position from one parent, and filling the remaining positions according to the order from the other parent. For parents \\( P \\) and \\( Q \\), first choose two random cutpoints to define a subsequence:\n\n\\[\nP = [1, 2, |3, 4, 5, 6, |7, 8, 9] \\\\\nQ = [8, 7, |9, 3, 4, 1, |2, 5, 6] \\\\\n\\text{child1} = [..., 3, 4, 5, 6, ...] \\\\\n\\text{child2} = [..., 9, 3, 4, 1, ...]\n\\]\n\nStarting at the second cutpoint and cycling back to the beginning, the elements of \\( Q \\) in order are as follows:\nAfter removing 3, 4, 5 and 6, which have already been placed in child1, you have the following entries:\n\n\\[\n\\begin{align*}\n2 & \\quad 8 & \\quad 7 & \\quad 9 & \\quad 1 \\\\\n\\end{align*}\n\\]\n\nPlacing these back in order starting at the second cutpoint yields the following sequence:\n\nchild1 = [9, 1, 3, 4, 5, 6, 2, 8, 7]\n\nApplying this logic to child2 yields the following sequence:\n\nchild2 = [5, 6, 9, 3, 4, 1, 7, 8, 2]\n\nThis operator maintains the similarity of the relative order, or adjacency, of the sequence elements of the parents. It is especially effective for circular path-oriented optimizations, such as the traveling salesman problem. For single-segment encoding, you can specify this operator with the call\n\n\\[\n\\text{call SetCross( 'Order' );}\n\\]\n\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n\\[\n\\text{call SetCross( 'Order', segment );}\n\\]\n\nFrom within a user crossover subroutine, you can use the call\n\n\\[\n\\text{call Cross( selected, segment, 'Order' );}\n\\]\n\nwhere selected is the selection parameter passed to your subroutine, and segment is the segment to which the order crossover operator is to be applied.\n\n**Pmatch**\n\nThe partial match operator is defined for sequence encoding. It produces offspring by transferring a subsequence from one parent, and filling the remaining positions in a way consistent with the position and ordering in the other parent. Start with two parents and randomly chosen cutpoints as indicated:\n\n\\[\n\\begin{align*}\nP & = [1, 2, [3, 4, 5, 6], [7, 8, 9]] \\\\\nQ & = [8, 7, [9, 3, 4, 1], [2, 5, 6]]\n\\end{align*}\n\\]\n\nThe first step is to cross the selected subsegments as follows (note that ‘.’ indicates positions yet to be determined):\n\nchild1 = [.., 9, 3, 4, 1, .., ..]\n\nchild2 = [.., 3, 4, 5, 6, .., ..]\n\nNext, define a mapping according to the two selected subsegments:\n\n9–3, 3–4, 4–5, 1–6\nThen, fill in the positions where there is no conflict from the corresponding parent, as follows:\n\n\\[\n\\text{child1} = \\{0, 2, 9, 3, 4, 1, 7, 8, \\ldots\\}\n\\]\n\n\\[\n\\text{child2} = \\{8, 7, 3, 4, 5, 6, 2, \\ldots\\}\n\\]\n\nLast, fill in the remaining positions from the subsequence mapping. In this case, for the first child, 1 → 6 and 9 → 3, 3 → 4, 4 → 5, and for the second child, 5 → 4, 4 → 3, 3 → 9, and 6 → 1.\n\n\\[\n\\text{child1} = \\{6, 2, 9, 3, 4, 1, 7, 8, 5\\}\n\\]\n\n\\[\n\\text{child2} = \\{8, 7, 3, 4, 5, 6, 2, 9, 1\\}\n\\]\n\nThis operator tends to maintain similarity of both the absolute position and relative ordering of the sequence elements, it and is useful for a wide range of sequencing problems. For single-segment encoding, you can specify this operator with the call\n\n```markdown\ncall SetCross( 'Pmatch' );\n```\n\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n```markdown\ncall SetCross( 'Pmatch', segment );\n```\n\nFrom within a user crossover subroutine, you can use the call\n\n```markdown\ncall Cross( selected, segment, 'Pmatch' );\n```\n\nwhere `selected` is the selection parameter passed to your subroutine, and `segment` is the segment to which the Pmatch crossover operator is to be applied.\n\n**Simple**\n\nThis operator is defined for integer, real, and Boolean encoding. It has one property, `alpha`. This operator performs the following action: a position \\( k \\) within an encoding of length \\( n \\) is chosen at random, such that \\( 1 ≤ k < n \\). Then for parents \\( P \\) and \\( Q \\), the offspring are as follows:\n\n\\[\n\\text{child1} = \\{P_1, P_2, \\ldots, P_k, Q_{k+1}, Q_{k+2}, \\ldots, Q_n\\}\n\\]\n\n\\[\n\\text{child2} = \\{Q_1, Q_2, \\ldots, Q_k, P_{k+1}, P_{k+2}, \\ldots, P_n\\}\n\\]\n\nFor integer and real encoding, you can specify an additional `alpha` property of value \\( a \\), where \\( 0 < a ≤ 1 \\). It modifies the offspring as follows:\n\n\\[\np_i = a P_i + (1 - a) Q_i, \\ i = k + 1, k + 2, \\ldots, n\n\\]\n\n\\[\nq_i = a Q_i + (1 - a) P_i, \\ i = k + 1, k + 2, \\ldots, n\n\\]\n\n\\[\n\\text{child1} = \\{P_1, P_2, \\ldots, P_k, q_{k+1}, q_{k+2}, \\ldots, q_n\\}\n\\]\n\n\\[\n\\text{child2} = \\{Q_1, Q_2, \\ldots, Q_k, p_{k+1}, p_{k+2}, \\ldots, p_n\\}\n\\]\n\nFor integer encoding, the elements are then rounded to the nearest integer. For Boolean encoding, the \\( a \\) parameter is ignored, and is effectively 1.\n\nFor single-segment encoding, you can specify this operator with the call\n\n```markdown\ncall SetCross( 'Simple', 'alpha', a );\n```\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n```c\n call SetCross('Simple', segment, 'alpha', a);\n```\n\nFrom within a user crossover subroutine, you can use\n\n```c\n call Cross(selected, segment, 'Simple', a);\n```\n\nwhere `selected` is the selection passed to your subroutine, and `segment` is the segment to which the simple crossover operator is to be applied.\n\n**Twopoint**\n\nThis operator is defined for integer, real, and Boolean encoding of length \\( n \\geq 3 \\), and has one property, `alpha`. Two positions, \\( k1 \\) and \\( k2 \\), are chosen at random, such that \\( 1 \\leq k1 < k2 < n \\). Element values between those positions are swapped between parents. For parents \\( Q \\) and \\( P \\), the offspring are as follows:\n\n\\[\n\\text{child1} = [P_1, P_2, \\ldots, P_{k1}, Q_{k1+1}, \\ldots, Q_{k2}, P_{k2+1}, \\ldots, P_n]\n\\]\n\n\\[\n\\text{child2} = [Q_1, Q_2, \\ldots, Q_{k1}, P_{k1+1}, \\ldots, P_{k2}, Q_{k2+1}, \\ldots, Q_n]\n\\]\n\nFor integer and real encoding, you can specify an additional `alpha` property of value \\( a \\), where \\( 0 < a \\leq 1 \\). It modifies the offspring as follows:\n\n\\[\np_i = aP_i + (1 - a)Q_i, \\quad i = k1 + 1, k1 + 2, \\ldots, k2\n\\]\n\n\\[\nq_i = aQ_i + (1 - a)P_i, \\quad i = k1 + 1, k1 + 2, \\ldots, k2\n\\]\n\n\\[\n\\text{child1} = [P_1, P_2, \\ldots, P_{k1}, q_{k1+1}, \\ldots, q_{k2}, P_{k2+1}, \\ldots, P_n]\n\\]\n\n\\[\n\\text{child2} = [Q_1, Q_2, \\ldots, Q_{k1}, p_{k1+1}, \\ldots, p_{k2}, Q_{k2+1}, \\ldots, Q_n]\n\\]\n\nNote that small values of \\( a \\) reduce the difference between the offspring and parents. For Boolean encoding, \\( a \\) is always 1. For single-segment encoding, you can specify the use of this operator with the call\n\n```c\n call SetCross('Twopoint', 'alpha', a);\n```\n\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n```c\n call SetCross(selected, segment, 'Twopoint', 'alpha', a);\n```\n\nFrom within a user crossover subroutine, you can use the call\n\n```c\n call Cross(selected, segment, 'Twopoint', a);\n```\n\nwhere `selected` is the selection passed to your subroutine, and `seg` is the segment to which the two-point crossover operator is to be applied.\n\n**Uniform**\n\nThis operator is defined for integer, real, and Boolean encoding of length \\( n \\geq 3 \\), and has two properties, `alpha` and \\( p \\), where \\( 0 < \\alpha \\leq 1 \\) and \\( 0 < p \\leq 0.5 \\). For \\( \\alpha = a \\) and parents \\( S \\) and \\( T \\), offspring \\( s \\) and \\( t \\) are generated such that\n\n\\[\ns_i = \\begin{cases} \naT_i + (1 - a)S_i, & \\text{with probability } p \\\\ \nS_i, & \\text{otherwise} \\end{cases}\n\\]\n\n\\[\nt_i = \\begin{cases} \naT_i + (1 - a)S_i, & \\text{with probability } p \\\\ \nT_i, & \\text{otherwise} \\end{cases}\n\\]\nChapter 4: The GA Procedure\n\n\\[\nt_i = \\begin{cases} \n aS_i + (1 - a)T_i, & \\text{with probability } p \\\\\n T_i, & \\text{otherwise}\n\\end{cases}\n\\]\n\nNote that \\( \\alpha \\) and \\( p \\) determine how much interchange there is between parents. Lower values of \\( \\alpha \\) and \\( p \\) imply less change between offspring and parents. For Boolean encoding, \\( \\alpha \\) is always assigned to be 1. If you do not specify \\( \\alpha \\), it defaults to a value of 1. If you do not specify \\( p \\), it defaults to a value of 0.5.\n\nFor single-segment encoding, you can specify the use of this operator with the call\n\n```\ncall SetCross('Uniform', 'alpha', a, 'p', p);\n```\n\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n```\ncall SetCross('Uniform', segment, 'alpha', a, 'p', p);\n```\n\nFrom within a user crossover subroutine, you can use the call\n\n```\ncall Cross(selected, seg, 'Uniform', a, p);\n```\n\nwhere \\( \\text{selected} \\) is the selection parameter passed to your crossover subroutine, and \\( \\text{seg} \\) is the segment to which the uniform crossover operator is to be applied. In both cases, if the encoding is Boolean, the \\( a \\) parameter is ignored, and \\( a \\) is effectively 1.\n\nMutation Operators\n\n**Delta**\n\nThis operator is defined for integer and real encoding. It has two properties, \\( \\delta \\) and \\( n\\text{change} \\). It first chooses \\( n \\) elements of the solution at random, where \\( n \\) is the value of the \\( \\text{nchange} \\) property, and then perturbs each chosen element by a fixed amount, set by \\( \\delta \\), the value of the \\( \\delta \\) property. \\( \\delta \\) must be an array with the same length as the encoding. A randomly chosen element \\( k \\) of the solution \\( S \\) is modified such that\n\n\\[\nS_k \\in \\{S_k - \\delta_k, S_k + \\delta_k\\}\n\\]\n\nIf upper and lower bounds are specified with a \\text{SetBounds} call, then \\( S_k \\) is adjusted as necessary to fit within the bounds. This operator gives you the ability to fine-tune the search by modifying the magnitude of the \\( \\delta \\) property. One possible strategy is to start with larger \\( \\delta \\) values, and then reduce them as the search progresses and begins to converge to an optimum. This operator is also useful if the optimum is known to be on or near a boundary, in which case \\( \\delta \\) can be set large enough to always perturb the solution element to a boundary. For single-segment encoding, you can specify this operator with the call\n\n```\ncall SetMut('delta', 'nchange', n, 'delta', \\delta);\n```\n\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n```\ncall SetMut('delta', segment, 'nchange', n, 'delta', \\delta);\n```\n\nYou can invoke this operator on a solution segment from within a user mutation subroutine with the call\n\n```\ncall Mutate(selected, segment, 'delta', \\delta, n);\n```\n\nwhere \\( \\text{selected} \\) is the selection parameter passed into the subroutine.\nUsing Standard Genetic Operators and Objective Functions\n\n**Invert**\n\nThis operator is defined for sequence encoding. It picks two locations at random and reverses the order of elements between them. This operator is most often applied to the traveling salesman problem. For single-segment encoding, you can specify this operator with the call\n\n```call SetMut ('invert');```\n\nFor multisection encoding, you can specify the segment to which the operator should be applied with the call\n\n```call SetMut ('invert', segment);```\n\nYou can invoke this operator on a solution segment from within a user mutation subroutine with the call\n\n```call Mutate (selected, segment, 'invert');```\n\nwhere `selected` is the selection parameter passed into the subroutine.\n\n**Null**\n\nThis operator is used to specify that no mutation operator be applied. It is not usually necessary to specify the null operator, except when you want to cancel a previous operator selection. You can specify the null operator with the call\n\n```call SetMut ('null');```\n\nFor multisection encoding, you can specify a segment to which the operator should be applied with\n\n```call SetMut ('null', segment);```\n\n**Swap**\n\nThis operator is defined for sequence problem encoding. It picks two random locations in the solution vector and swaps their values. You can also specify that multiple swaps be made for each mutation, by setting the `nswap` property. For single-segment encoding, you can specify the swap operator with the call\n\n```call SetMut ('swap', 'nswap', n);```\n\nwhere `n` is the number of swaps for each mutation. For multisection encoding, you can specify the segment to which the operator should be applied with the call\n\n```call SetMut ('swap', segment, 'nswap', n);```\n\nYou can invoke this operator on a solution segment from within a user mutation subroutine with the call\n\n```call Mutate (selected, segment, 'swap', n);```\n\nwhere `selected` is the selection parameter passed into the subroutine.\n\n**Uniform**\n\nThis operator is defined for Boolean encoding or for real or integer encoding with upper and lower bounds specified with a `SetBounds` call. To apply this operator, a position `k` is randomly chosen within the solution `S`, and `S_k` is modified to a random value between the upper and lower bounds for element `k`. There are two properties you can specify, `nchange` and `pchange`. If you set the `nchange` property to `n`, the operator is applied to `n` locations. If you set the `pchange` property to a value `p`, where `0 < p < 1`, the operator is applied at each position with probability `p`. Only the last property setting is active, overriding any previous\nsettings. If no property is set, a default \\textit{nchange} value of 1 is used. You can specify this operator with one of the following two calls:\n\n\\begin{verbatim}\ncall SetMut('uniform', 'nchange', n);\ncall SetMut('uniform', 'pchange', p);\n\\end{verbatim}\n\nFor multisegment encoding, you can specify the segment to which the operator should be applied with the call\n\n\\begin{verbatim}\ncall SetMut('uniform', 'segment', 'nchange', n);\n\\end{verbatim}\n\nYou can invoke this operator on a solution segment from within a user mutation subroutine by using one of the following statements, where \\textit{selected} is the selection parameter passed into the subroutine:\n\n\\begin{verbatim}\ncall Mutate(selected, 'segment', 'uniform', n);\ncall Mutate(selected, 'segment', 'uniform', p);\n\\end{verbatim}\n\nThis operator can prove especially useful in early stages of the optimization, since it tends to distribute solutions widely across the search space, and to avoid premature convergence to a local optimum. However, in later stages of an optimization, when the search needs to be fine-tuned to home in on an optimum, the uniform operator can hinder the optimization.\n\n**Objective Functions**\n\n**TSP**\n\nThe TSP objective calculates the value of the traveling salesman problem objective. It has one property, \\textit{distances}, which is a two-dimensional array representing distances between locations. If \\textit{distances} = \\(d\\), then \\(d[i,j]\\) is the distance between location \\(i\\) and location \\(j\\).\n\n**Defining a User Fitness Comparison Routine**\n\nMost of the selection techniques used in this procedure require comparisons of fitness to decide which solutions should be propagated into the next generation. Normally fitness is directly related to the solution objective value, with the better objective value indicating the higher fitness. However, sometimes it is useful to base fitness on multiple criteria, not just a single calculated objective value. Doing so enables you to solve multiobjective optimization problems, or to find optima that also satisfy secondary objectives. For example, for a multiobjective problem you might want to find a set of construction schedules that simultaneously minimize completion time and minimize cost, so that you can examine the tradeoff between the two objectives and choose a schedule that best meets your needs. You might also have a scheduling problem where there is more than one solution that meets your primary objective, but you would like to converge on the one that also provides adequate worker breaks, or minimizes overtime. One single-valued objective function might not be adequate to express these preferences.\n\nYou can define a function and designate that function to be used for comparing the fitness of two competing solutions with the call\n\n\\begin{verbatim}\ncall SetCompareRoutine('routine');\n\\end{verbatim}\n\nwhere \\textit{routine} is the name of the function you have defined. The function name must be a quoted string. The first parameter of the function, designated the \\textit{selection} parameter, must be a numeric array. The procedure\nDefining a User Fitness Comparison Routine\n\ncalls your compare function whenever it needs to compare the fitness of two solutions. Your function can also have an arbitrary number of additional parameters, whose names and data types should match variables defined in the global portion of your input. When the procedure calls your function, the selection parameter will be filled in with information identifying which solutions are to be compared, and any other parameters will be filled in with the corresponding global symbol values. Your function should not alter the selection parameter in any way, but pass it unchanged into a ReadCompare Call to obtain the solution elements your program needs to compare the fitness. If solution 1 has higher fitness than solution 2, then your function should return a positive number. If solution 2 is more fit than solution 1, then a negative number should be returned. If the two solutions have the same fitness then a value of 0 might be returned. Following is a simple example of a fitness comparison function.\n\n```plaintext\n/* This function is designed to maximize a */\n/* primary and secondary objective. The objectives */\n/* are stored in segment 2 of the encoding. If */\n/* the difference in primary objective is less than */\n/* the value of delta, then the secondary objective */\n/* is used to determine the fitness */\nfunction compare2(selected[*], delta);\n\n/* arrays to hold solution elements */\narray member1[2] /nosym;\narray member2[2] /nosym;\n\n/* read segment 2 of solution 1 into member1 */\ncall ReadCompare(selected, 2, 1, member1);\n\n/* read segment 2 of solution 2 into member2 */\ncall ReadCompare(selected, 2, 2, member2);\n\n/* element 1 contains the primary objective value, */\n/* element 2 contains a secondary objective value */\n/* if objective 1 is nearly the same, then use */\n/* objective 2 to compare the fitness */\nif( abs(member1[1] - member2[1]) < delta) then do;\n /* primary objectives are nearly the same, check secondary */\n if(member1[2] > member2[2]) then\n return(1);\n if(member2[2] > member1[2]) then\n return(-1);\nend;\n\n/* base fitness on primary objective */\nif(member1[1] > member2[1]) then\n return(1);\nif(member2[1] > member1[1]) then\n return(-1);\n\n/* all objectives are the same, return 0 */\nreturn(0);\nendsub;\n```\n/* in global scope of the input */\ndelta = 0.01;\ncall SetCompareRoutine('compare2');\n\nFor an example of a comparison routine used in a multiobjective optimization, see Example 4.3.\n\n---\n\n### Defining User Genetic Operators\n\nYou can define new genetic operators with subroutines. The GA procedure calls your subroutine when it is necessary to perform mutation or crossover operations. You can designate that a subroutine be used for crossover with the call\n\n```plaintext\ncall SetCrossRoutine('routine');\n```\n\nwhere `routine` is the name of the subroutine you have defined. Similarly, you can designate a subroutine for the mutation operator with the call\n\n```plaintext\ncall SetMutRoutine('routine');\n```\n\nThe subroutine name must be a quoted string. The first parameter of the crossover or mutation subroutine you define must be a numeric array. When the GA procedure calls your subroutine, it passes information in the first parameter, referred to as the *selection* parameter, which designates the selected members for the operation. You should not alter the selection parameter in any way, but pass it unchanged into special utility routines provided by the GA procedure in order to obtain the solution elements and write them to the selected members. You can define as many other parameters to your subroutine as you need; they are filled in with values from variables of the same name created in the global portion of your program. Any array parameters must be numeric and of the type /NOSYMBOLS.\n\nFor a crossover subroutine, use the **ReadParent** call to get the elements of the selected parents into arrays that you can then manipulate with programming statements. The results can be written to the designated offspring with a **WriteChild** call. The following code is an example of a crossover subroutine. The subroutine creates two new offspring from two selected parents by switching the odd-numbered elements between the two parents.\n\n```plaintext\n/* single-segment integer encoding of size 10 */\ncall SetEncoding('I10');\n\n/* encoding size is 10 */\nn = 10;\n\nsubroutine swapodd(selected[*], n);\n array child1[1] /nosym;\n array child2[1] /nosym;\n\n /* reallocate child arrays to right size */\ncall dynamic_array(child1,n);\ncall dynamic_array(child2,n);\n\n /* read segment 1 from parent 1 into child1 */\ncall ReadParent(selected, 1, 1, child1);\n```\n/* read segment 1 from parent 2 into child2 */\ncall ReadParent(selected, 1, 2, child2);\n/* swap the odd elements in the solution */\ndo i = 1 to n by 2;\n temp = child1[i];\n child1[i] = child2[i];\n child2[i] = temp;\nend;\n/* write offspring out to selected children */\ncall WriteChild(selected, 1, 1, child1);\ncall WriteChild(selected, 1, 2, child2);\nendsub;\n/* designate swapodd as the crossover routine */\ncall SetCrossRoutine('swapodd');\n\nThe next sample program illustrates a crossover routine that might be used for multisegment mixed integer and sequence encoding. The subroutine uses the standard Simple crossover operator for the integer segment, and the Pmatch operator for the sequence-encoded segment.\n\n/* Solution has 2 segments, integer I5 and sequence S5 */\ncall SetEncoding('I5S5');\n/* alpha parameter for Simple crossover operator */\nalpha = 1;\nsubroutine mixedIS(selected[*], alpha);\n /* execute simple operator on segment 1 */\ncall Cross(selected, 1, 'Simple', alpha);\n /* execute pmatch operator on segment 2 */\ncall Cross(selected, 2, 'Pmatch');\nendsub;\ncall SetCrossRoutine('mixedIS');\n\nFor a mutation subroutine, use a ReadMember call to obtain the elements of the solution selected to be mutated, and use a WriteMember call to write the mutated elements back to the solution. For example, the following statements define a mutation subroutine that swaps two adjacent elements at a randomly chosen position in a sequence:\n\n/* Solution has 1 segment, sequence S10 */\ncall SetEncoding('S10');\nn = 10;\nsubroutine swap2(selected[*], n);\n/* declare an array for working memory */\narray member[1] /nosym;\n\n/* allocate array to required length */\ncall dynamic_array(member, n);\n\n/* read segment 1 of selected member into array */\ncall ReadMember(selected,1,member);\n\n/* generate random number between 0 and 1 */\nr = rand('uniform');\n\n/* convert r to integer between 1 and n-1 */\ni = int(r * (n - 1)) + 1;\n\n/* swap element values */\ntemp = member[i];\nmember[i] = member[i+1];\nmember[i+1] = temp;\n\n/* write result back out to solution */\ncall WriteMember(selected,1,member);\n\nendsub;\n\n/* Set the mutation routine to swap2 */\ncall SetMutRoutine('swap2');\n\n---\n\n**Defining a User Update Routine**\n\nThe GA procedure enables you to define a routine that is to be called at each generation in the optimization process, after the designated objective function has been evaluated for each solution, before the selection process takes place. Some of the tasks that can be handled with an update routine include evaluating global solution fitness criteria, logging intermediate optimization progress, evaluating termination criteria and stopping the optimization, modifying the properties of the genetic operators to intensify or diversify the search process, or even to reinitialize portions of the solution population. You can designate a user update function with the call\n\n```\ncall SetUpdateRoutine('name');\n```\n\nwhere `name` is the name of the routine you have defined.\n\nThe parameters defined for the update routine must correspond to variables of the same name established in the global portion of your procedure input. If you desire to update a parameter and have that update retained across generations, that parameter must also be declared in an OUTARGS statement in the update routine definition. The following program snippet illustrates how a user might specify an update routine that monitors the best objective value at each generation and terminates the optimization when no improvement is seen after a specified number of iterations.\nsubroutine no_improvement_terminator(iteration, \n saved_value, \n nsame, \n same_limit, \n populationSize);\n\noutargs iteration, saved_value, nsame;\n\narray objValues[1] /nosym;\n\n/* dynamically allocate array to fit populationSize */\ncall dynamic_array(objValues, populationSize);\n\n/* read in current objective values */\ncall GetObjValues(objValues, populationSize);\n\n/* find best value */\ncurrent_best = objValues[1];\ndo i = 2 to populationSize;\n /* for a minimization problem, use < here */\n if(objValues[i] > current_best) then\n current_best = objValues[i];\nend;\n\nif iteration > 0 then do;\n /* for a minimization problem, use < here */\n if current_best > saved_value then do;\n /* reset same value counter */\n nsame = 1;\n saved_value = current_best;\n end;\n else do;\n /* increment same value counter */\n nsame = nsame + 1;\n /* if counter equals limit, then make this the last generation */\n if nsame >= same_limit then\n call ContinueFor(0);\n end;\nend;\nelse do;\n saved_value = current_best;\n nsame = 1;\nend;\n\niteration = iteration + 1;\nendsub;\n\niteration = 0;\nsaved_value = 0;\nnsame = 0;\n/* terminate when no improvement after 30 generations */\nsame_limit = 30;\npopulationSize = 100;\ncall SetUpdateRoutine('no_improvement_terminator');\nFrom within a user update routine you can use a GetObjValues call to get the current solution objective values, a GetSolutions call to get the current solution population, an UpdateSolutions call to reset solution values, a ReEvaluate call to recompute objective values, or an Initialize call to reinitialize and resize the solution population.\n\n### Defining an Objective Function\n\nThe GA procedure enables you to specify your objective to be optimized with a function you create, or as a standard objective function that the GA procedure provides. Currently the only standard objective you can specify without writing an objective function is the traveling salesman problem, which can be specified with a SetObj call. In the future, other objective functions will be added. You can designate a user objective function with the call\n\n```plaintext\ncall SetObjFunc('name', minmax);\n```\n\nwhere *name* is the name of the function you have defined, and *minmax* is set to 0 to specify a minimum or 1 to specify a maximum.\n\nA user objective function must have a numeric array as its first parameter. When the GA procedure calls your function, it passes an array in the first parameter that specifies the selected solution, which is referred to as the *selection* parameter. The selection parameter must not be altered in any way by your function. Your function should pass the selection parameter to a ReadMember call to read the elements of the selected solution into an array. Your function can then access this array to compute an objective value, which it must return. As with the genetic operator routines, you can define additional arguments to your objective function, and the GA procedure passes in variables with corresponding names that you have created in your global program. For example, the following statements set up an objective function that minimizes the sum of the squares of the solution elements:\n\n```plaintext\ncall SetEncoding('R5');\n\nn = 5;\n\nfunction sumsq(selected[*], n);\n\n /* set up a scratch array to hold solution elements */\n array x[1] /nosym;\n\n /* allocate x to hold all solution elements */\n call dynamic_array(x, n);\n\n /* read members of the selected solution into x */\n call ReadMember(selected, 1, x);\n\n /* compute the sum of the squares */\n sum = 0;\n do i = 1 to n;\n sq = x[i] * x[i];\n sum = sum + sq;\n end;\n```\n\n```plaintext\nend;```\nDefining a User Initialization Routine\n\nFor problems with simple constant bounds or simple sequencing problems it is not necessary to define a user initialization subroutine; simply specify ‘DEFAULT’ in the Initialize call. Defining a routine is necessary only if you need to satisfy more complicated constraints or apply some initial heuristics or local optimizations. A user initialization routine is specified with an Initialize call, as follows:\n\n```sas\ncall Initialize('name', size);\n```\n\nwhere `name` is the name of your initialize routine. The first parameter of the subroutine you define must be a numeric array. When the GA procedure calls your subroutine, it passes information in the first parameter, referred to as the `selection` parameter, which designates the member selected for initialization. Your subroutine should generate one solution and write the values of the solution elements with a `WriteMember` call, using the selection parameter passed to your subroutine. The random number functions from BASE SAS are available to your subroutine, if needed. You can define as many other parameters to your subroutine as you need; they are filled in with values from variables of the same name created in your global program. The array used to write the generated solution to the population must be numeric and declared with the `/NOSYMBOLS` option, as well as any arrays passed as parameters into your subroutine.\n\nThe following sample statements illustrate how to define an initialization routine. The feasible region is a triangle with vertices (0,0), (0,1) and (1,1).\n\n```sas\ncall SetEncoding('R2');\n\n/* set vertices of triangle (0,0), (0,1), and (1,1) */\narray vertex1[2] /nosym (0,0);\narray vertex2[2] /nosym (0,1);\narray vertex3[2] /nosym (1,1);\n\nsubroutine triangle(selected[*], vertex1[2], vertex2[2], vertex3[2]);\n\narray x[2] /nosym;\n\n/* select 3 random numbers 0 < r < 1 */\nr1 = rand('uniform');\nr2 = rand('uniform');\nr3 = rand('uniform');\n\n/* normalize so r1 + r2 + r3 = 1 */\nsumr = r1 + r2 + r3;\n```\n\nIn this example, the function `SUMSQ` is defined, and the `SetObjFunc` call establishes it as the objective function. The 0 for the second parameter of the `SetObjFunc` call indicates that the objective should be minimized. Note that the second parameter to the `SUMSQ` function, `n`, is defined in the procedure, and the value assigned to it there is passed into the function.\n\\[ r_1 = \\frac{r_1}{\\text{sum}_r}; \\]\n\\[ r_2 = \\frac{r_2}{\\text{sum}_r}; \\]\n\\[ r_3 = \\frac{r_3}{\\text{sum}_r}; \\]\n\n\\[\n\\text{/* form a convex combination of vertices in } x */\n\\]\n\\[\n\\text{do } i = 1 \\text{ to } 2; \\\\\n\\quad x[i] = r_1 \\ast \\text{vertex}_1[i] + r_2 \\ast \\text{vertex}_2[i] + r_3 \\ast \\text{vertex}_3[i]; \\\\\n\\text{end;}\n\\]\n\n\\[\n\\text{/* write } x \\text{ out to the selected population member, to segment 1 */}\n\\]\n\\[\n\\text{call WriteMember(selected, 1, } x); \\\\\n\\text{endsub;}\n\\]\n\n[other programming statements]\n\n\\[\n\\text{call Initialize('triangle',100);} \\\\\n\\]\n\nIn this example, the triangle initialization subroutine generates a solution that is a random convex combination of three points, which places it in the interior of the triangular region defined by the points. Note the use of the \\textsc{base sas} \\texttt{rand()} function to get random numbers uniformly distributed between 0 and 1. The random numbers are then normalized so that their sum is 1. In the loop, they are used to compute a convex linear combination of the vertices, and the \\texttt{WriteMember} call writes the solution to the selected population member. The encoding specified a single segment, so the \\texttt{WriteMember} call specifies segment 1 as the target. When the \\texttt{GA} procedure executes the \\texttt{Initialize} call, it executes the triangle routine 100 times, once for each member of the initial population.\n\n---\n\n**Specifying the Selection Strategy**\n\nThere are a number of different strategies that can employed to select the most fit solutions from a population to be propagated into the next solution generation. Regardless of the strategy chosen, the user must try set the selection properties to maintain a productive balance between selection pressure and preservation of diversity. Enough selective pressure must be maintained to drive the algorithm toward an optimum in a reasonable time, but too much selective pressure will eliminate the diversity of the population too quickly and lead to premature convergence to a suboptimal solution. One effective technique is to start the optimization process at a lower selective pressure, and increase it as the optimization continues. You can easily do this in the \\texttt{GA} procedure by modifying the selection strategy with a \\texttt{SetProperty} call inside an \\texttt{update} routine. A description of the selection strategies and their properties follows.\n\n**Tournament Selector**\n\nThis selector has one property, \\textit{size}. The selector repeats the following process until the next generation of solutions has been specified: randomly choose a small subset of the current population, and then select the most fit from that subset. The selection pressure is controlled by the size of the subset chosen, specified by the \\textit{size} property. Tournament sizes from 2 to 10 have been successfully applied to various genetic algorithm optimizations, with sizes over 4 or 5 considered to represent strong selective pressure. If the \\textit{size} property is not set by the user, it defaults to a value of 2. The \\textit{Duel} selector is a modification of this selector that permits further lowering of selection pressure.\nWith this selector the objective value is normally used to compare the fitness of competing solutions, with better objective values corresponding to higher fitness. However, there are techniques for multiple objective optimization and constraint handling that use more complicated criteria than just the objective value. See the section “Optimizing Multiple Objectives” on page 135 for further discussion of this topic. You can set your own fitness comparison routine to implement those techniques with the SetCompareRoutine call, and that routine will be used by the tournament selector to compare solution fitness. For a simple single-objective problem you normally do not need to specify a special fitness comparison routine, unless have a secondary objective you might want to use to break a tie.\n\nDuel Selector\n\nThis selector has one property, $bprob$. It operates in the same manner as the Tournament selector with tournament size 2, except it permits you to reduce selection pressure further by specifying a probability, $bprob$, for selecting the most fit solution from the pair. The $bprob$ property is assigned a default value of 0.8, but you can change it to a value between 0.5 (corresponding to pure random selection) and 1. By default, solution fitness is compared by comparing the solution objective values. However, you can also set your own fitness comparison routine with the SetCompareRoutine call. See the tournament selector for a discussion of when you would need to specify a special fitness comparison routine.\n\nIncorporating Heuristics and Local Optimizations\n\nIt is often effective to combine the genetic algorithm technique and other local optimizations or heuristic improvements. This can be done within the GA procedure by incorporating a local optimization into a user objective function and returning an improved objective value. Either your user objective function can replace the original solution with the optimized one, or you can leave the solution unchanged, replacing it with the optimized one only at the final iteration.\n\nReplacing the original solution with the locally optimized one speeds convergence, but it also increases the risk of converging prematurely. If you choose to do so, you can modify the solution by writing the changed solution back to the population with a WriteMember call. You could also consider replacing the original solution with some probability $p$. For some problems, values of $p$ from 0.05 to 0.15 have been shown to significantly improve convergence while avoiding premature convergence to a local optimum. This technique is illustrated in Example 4.1.\n\nHandling Constraints\n\nPractical optimization problems usually involve constraints, which can make the problems harder to solve. Constraints are handled in genetic algorithms in several ways.\n\nEncoding Strategy\n\nThe simplest approach is to set the problem encoding, genetic operators, and initialization such that the constraints are automatically satisfied. Fixed constant bounds are easily handled in this manner in the GA procedure with the SetBounds call. The default initialization process and genetic operators provided by the GA procedure automatically respect bounds specified in this manner. For some types of constraints, you might be able to create a direct mapping from a constrained solution domain to a second domain with simple\nconstant bounds. You could then define your genetic operator to map the solution into the second domain, apply one of the standard genetic operators, and then map the result back to the original domain.\n\nIf the problem contains equality constraints, you should try to transform the problem to eliminate the equality constraints and reduce the number of variables. This strategy is opposite from what is usually done in linear programming, where inequality constraints are turned into equality constraints by the addition of slack variables.\n\n**Repair Strategy**\n\nIf the constraints are more complex and cannot be easily satisfied automatically by the genetic operators, you might be able to employ a repair strategy: check the solution and modify it to satisfy the constraints. The check and repair can be done in a user genetic operator when the solution is generated, or it can be done in the evaluation phase in a user objective function. Possible strategies for making a repair inside an objective function include projecting the solution onto the constraint boundary; while inside a genetic operator you might try adjusting an operator parameter until the constraint is satisfied. If you do the repair in the objective function, you should compute the objective value after performing the repair. You can write the repaired solution back out to the population with a WriteMember call from a user objective function or mutation subroutine, and with a WriteChild call from within a crossover subroutine. Example 4.2 illustrates the use of the repair strategy.\n\n**Penalty Strategy**\n\nAnother technique is to permit solutions to violate constraints, but also to impose a fitness penalty that causes the population to evolve toward satisfying constraints as well as optimizing the objective. One way of employing this strategy is to simply add a penalty term to the objective function, but this approach should be used with care, because it is not always obvious how to construct the penalty function in a way that does not bias the optimization of the desired objective.\n\n**Direct Comparison Strategy**\n\nUsing tournament selection opens another possibility for handling constraints. Define a fitness comparison routine (designated in a SetCompareRoutine call) that employs the following logic:\n\n1. If neither solution is feasible, choose the one closest to satisfying the constraints.\n2. If one solution is feasible, and the other is not, choose the feasible one.\n3. If both solutions are feasible, choose the one with the best objective value.\n\nThis strategy has the advantage that the objective function does not have to be calculated for infeasible solutions. To implement this method, you need to provide a measure of constraint violation and compute it in a user objective function; this value can be used in the first comparison step outlined previously. For linear constraints, the GA procedure provides the EvaluateLC call for this purpose. The technique works best when the solution space normally contains a significant number of solutions that satisfy the constraints. Otherwise it is possible that a single feasible solution might quickly dominate the population. In such cases, a better approach might be the following Bicriteria Comparison Strategy.\nOptimizing Multiple Objectives\n\nMany practical optimization problems involve more than one objective criteria, where the decision maker needs to examine trade-offs between conflicting objectives. With traditional optimization methods, these problems are often handled by aggregating multiple objectives into a single scalar objective, usually accomplished by some linear weighting of the multiple criteria. Other approaches involve turning objectives into constraints. One disadvantage of this strategy is that many separate optimizations with different weighting factors or constraints need to be performed to examine the trade-offs between different objectives. Genetic algorithms enable you to attack multiobjective problems directly, in order to evolve a set of solutions in one run of the optimization process instead of solving multiple separate problems.\n\nThis approach seeks to evolve the Pareto-optimal set: the set of solutions such that for each solution, all the objective criteria cannot be simultaneously improved. This is expressed mathematically by the concept of Pareto optimality. A Pareto-optimal set is the set of all nondominated solutions, according to the following definition of dominated:\n\nFor an $n$-objective minimizing optimization problem, for each objective function $f_i$, a solution $p$ is dominated by $q$ if\n\n$$f_i(p) \\geq f_i(q) \\text{ for all } i = 1, \\ldots, n \\text{ and } f_j(p) > f_j(q) \\text{ for some } j = 1, \\ldots, n$$\n\nThe following is one strategy that can be employed in the GA procedure to evolve a set of Pareto-optimal solutions to a multiobjective optimization problem:\n\n**user objective function:** Define and specify a user objective function in a `SetObjFunc` call that computes each of the objective criteria and stores the objective values in one single solution segment.\n\n**user update routine:** Define and specify a user update routine in a `SetUpdateRoutine` call that examines the entire solution population and marks those in the Pareto-optimal set. This can be done with the `MarkPareto` call provided by the GA procedure. Also, set the `elite` parameter equal to the number of Pareto-optimal solutions found.\n\n**selection criteria:** Define a fitness comparison routine that favors the least dominated solutions, and designate it in a `SetCompareRoutine` call. For selecting between two solutions when neither solution dominates the other, your routine can check a secondary criterion to direct the search to the area of ultimate interest.\n\nThe multiple objective values are recorded in one segment to enable the use of the `MarkPareto` call provided by the GA procedure. Setting the `elite` selection parameter to the size of the Pareto-optimal set, in conjunction with the comparison criteria, guarantees that the Pareto-optimal set in each generation is preserved to the next.\nThe secondary comparison criterion can be used to ensure that the final Pareto-optimal set is distributed in the area of ultimate interest. For example, for the Bicriteria Constraint Strategy described previously, the actual area of interest is where there is zero constraint violation, which is the second objective. The secondary comparison criterion in that case is to minimize the value of the constraint violation objective. After enough iterations, the population should evolve to the point that the best solution to the bicriteria problem is also the best solution to the original constrained problem, and the other Pareto-optimal solutions can be examined to analyze the sensitivity of the optimum solution to the constraints. For other types of problems, you might need to implement a more complicated secondary comparison criterion to avoid “crowding” of solutions about some arbitrary point, and ensure the evolved Pareto-optimal set is distributed over a range of objective values.\n\nExamples: GA Procedure\n\nExample 4.1: Traveling Salesman Problem with Local Optimization\n\nThis example illustrates the use of the GA procedure to solve a traveling salesman problem (TSP); it combines a genetic algorithm with a local optimization strategy. The procedure finds the shortest tour of 20 locations randomly oriented on a two-dimensional $x$-$y$ plane, where $0 \\leq x \\leq 1$ and $0 \\leq y \\leq 1$. The location coordinates are input in the following DATA step:\n\n```sas\n/* 20 random locations for a Traveling Salesman Problem */\ndata locations;\t\t\n input x y;\n datalines;\n 0.0333692 0.9925079\n 0.6020896 0.0168807\n 0.1532083 0.7020444\n 0.3181124 0.1469288\n 0.1878440 0.8679120\n 0.9786112 0.4925364\n 0.7918010 0.7943144\n 0.5145329 0.0363478\n 0.5500754 0.8324617\n 0.3893757 0.6635483\n 0.9641841 0.6400201\n 0.7718126 0.5463923\n 0.7549037 0.4584584\n 0.2837881 0.7733415\n 0.3308411 0.1974851\n 0.7977221 0.1193149\n 0.3221207 0.7930478\n 0.9201035 0.1186234\n 0.2397964 0.1448552\n 0.3967470 0.6716172\n;```\n\nExample 4.1: Traveling Salesman Problem with Local Optimization\n\nFirst, the GA procedure is run with no local optimizations applied:\n\n```plaintext\nproc ga data1 = locations seed = 5554;\n call SetEncoding('S20');\n ncities = 20;\n array distances[20,20] /nosym;\n do i = 1 to 20;\n do j = 1 to i;\n distances[i,j] = sqrt((x[i] - x[j])**2 + (y[i] - y[j])**2);\n distances[j,i] = distances[i,j];\n end;\n end;\n call SetObj('TSP',0,'distances', distances);\n call SetCross('Order');\n call SetMut('Invert');\n call SetMutProb(0.05);\n call SetCrossProb(0.8);\n call SetElite(1);\n call Initialize('DEFAULT',200);\n call ContinueFor(140);\nrun;\n```\n\nThe PROC GA statement uses a DATA1= option to get the contents of the locations data set, which creates array variables x and y from the corresponding fields of the data set. A solution will be represented as a circular tour, modeled as a 20-element sequence of locations, which is set up with the SetEncoding call. The array variable distances is created, and the loop initializes distances from the x and y location coordinates such that distances[i,j] is the Euclidean distance between location i and j. Next, the SetObj call specifies that the GA procedure use the included TSP objective function with the distances array. Then, the genetic operators are specified, with SetCross for the crossover operator and SetMut for the mutation operator. Since the crossover probability and mutation probability are not explicitly set in this example, the default values of 1 and 0.05, respectively, are used. The selection parameters are not explicitly set (with SetSel and SetElite calls), so by default, a tournament of size 2 is used, and an elite parameter of 1 is used. Next, the Initialize call specifies default initialization (random sequences) and a population size of 100. The ContinueFor call specifies a run of 220 iterations. This value is a result of experimentation, after it was determined that the solution did not improve with more iterations. The output of this run of PROC GA is given in Output 4.1.1.\n\n### Output 4.1.1\nSimple Traveling Salesman Problem\n\n#### PROC GA Optimum Values\n\n| Objective | 3.7465311323 |\nChapter 4: The GA Procedure\n\nOutput 4.1.1 continued\n\n<table>\n<thead>\n<tr>\n<th>Solution Element</th>\n<th>Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>12</td>\n</tr>\n<tr>\n<td>2</td>\n<td>13</td>\n</tr>\n<tr>\n<td>3</td>\n<td>18</td>\n</tr>\n<tr>\n<td>4</td>\n<td>16</td>\n</tr>\n<tr>\n<td>5</td>\n<td>2</td>\n</tr>\n<tr>\n<td>6</td>\n<td>8</td>\n</tr>\n<tr>\n<td>7</td>\n<td>15</td>\n</tr>\n<tr>\n<td>8</td>\n<td>4</td>\n</tr>\n<tr>\n<td>9</td>\n<td>19</td>\n</tr>\n<tr>\n<td>10</td>\n<td>3</td>\n</tr>\n<tr>\n<td>11</td>\n<td>1</td>\n</tr>\n<tr>\n<td>12</td>\n<td>5</td>\n</tr>\n<tr>\n<td>13</td>\n<td>14</td>\n</tr>\n<tr>\n<td>14</td>\n<td>17</td>\n</tr>\n<tr>\n<td>15</td>\n<td>10</td>\n</tr>\n<tr>\n<td>16</td>\n<td>20</td>\n</tr>\n<tr>\n<td>17</td>\n<td>9</td>\n</tr>\n<tr>\n<td>18</td>\n<td>7</td>\n</tr>\n<tr>\n<td>19</td>\n<td>11</td>\n</tr>\n<tr>\n<td>20</td>\n<td>6</td>\n</tr>\n</tbody>\n</table>\n\nThe following program illustrates how the problem can be solved in fewer iterations by employing a local optimization. Inside the user objective function, before computing the objective value, every adjacent pair of cities in the tour is checked to determine if reversing the pair order would improve the objective value. For a pair of locations $S_i$ and $S_{i+1}$, this means comparing the distance traversed by the subsequence \\( S_{i-1}, S_i, S_{i+1}, S_{i+2} \\) to the distance traversed by the subsequence \\( S_{i-1}, S_{i+1}, S_i, S_{i+2} \\), with appropriate wrap-around at the endpoints of the sequence. If the distance for the swapped pair is smaller than the original pair, then the reversal is done, and the improved solution is written back to the population.\n\n```plaintext\nproc ga data1 = locations seed = 5554;\n call SetEncoding('S20');\n ncities = 20;\n array distances[20,20] /nosym;\n do i = 1 to 20;\n do j = 1 to i;\n distances[i,j] = sqrt((x[i] - x[j])**2 + (y[i] - y[j])**2);\n distances[j,i] = distances[i,j];\n end;\n end;\n /* Objective function with local optimization */\n function TSPSwap(selected[*],ncities,distances[*,*]);\n array s[1] /nosym;\n call dynamic_array(s,ncities);\n call ReadMember(selected,1,s);\n```\n/* First try to improve solution by swapping adjacent cities */\ndo i = 1 to ncities;\ncity1 = s[i];\ninext = 1 + mod(i,ncities);\ncity2 = s[inext];\nif i=1 then\n before = s[ncities];\nelse\n before = s[i-1];\n after = s[1 + mod(inext,ncities)];\nif (distances[before,city1]+distances[city2,after]) >\n (distances[before,city2]+distances[city1,after]) then do;\n s[i] = city2;\n s[inext] = city1;\nend;\nend;\ncall WriteMember(selected,1,s);\n/* Now compute distance of tour */\ndistance = distances[s[ncities],s[1]];\ndo i = 1 to (ncities - 1);\n distance + distances[s[i],s[i+1]];\nend;\nreturn(distance);\nendsub;\ncall SetObjFunc('TSPSwap',0);\ncall SetCross('Order');\ncall SetMut('Invert');\ncall SetMutProb(0.05);\ncall SetCrossProb(0.8);\ncall SetElite(1);\ncall Initialize('DEFAULT',200);\ncall ContinueFor(35);\nrun;\n\nThe output after 85 iterations is given in Output 4.1.2.\n\n### Output 4.1.2 \nTraveling Salesman Problem with Local Optimization\n\n**PROC GA Optimum Values**\n\n<table>\n<thead>\n<tr>\n<th>Objective</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>3.7465311323</td>\n</tr>\n</tbody>\n</table>\nOutput 4.1.2 continued\n\nSince all tours are circular, the actual starting point does not matter, and this solution is equivalent to that reached with the simple approach without local optimization. It is reached after only 85 iterations, versus 220 with the simple approach.\n\n**Note:** For an example of how to use PROC OPTNET to solve the TSP, see the “Examples” section in Chapter 2, “The OPTNET Procedure” (SAS/OR User’s Guide: Network Optimization Algorithms).\n\n---\n\n**Example 4.2: Nonlinear Objective with Constraints Using Repair Mechanism**\n\nThis example illustrates the use of a repair mechanism to satisfy problem constraints. The problem is to minimize the six-hump camel-back function (Michalewicz 1996, Appendix B):\n\n\\[\nf(x) = \\left( 4 - 2.1x_1^2 + \\frac{x_1^4}{3} \\right) x_1^2 + x_1x_2 + \\left( -4 + 4x_2^2 \\right) x_2^2\n\\]\n\nwhere \\( x \\) is within the triangle with vertices \\( V_1 = (-2, 0), V_2 = (0, 2), \\) and \\( V_3 = (2, -2) \\). The problem formulation takes advantage of the fact that all feasible solutions can be expressed as a convex combination of \\( V_1, V_2, \\) and \\( V_3 \\) in the following form:\n\n\\[\nx = aV_1 + bV_2 + cV_3\n\\]\n\nIn this form, \\( a, b, \\) and \\( c \\) are nonnegative coefficients and satisfy the following linear equality constraint:\n\n\\[\na + b + c = 1\n\\]\nTherefore, the solution encoding ‘R3’ is used with the three elements corresponding to the values of $a$, $b$, and $c$. Note that this strategy can be generalized to any solution domain that can be specified by a convex hull. An additional ‘R2’ segment is also created to store the corresponding $x$ value. In the following program, \\texttt{FUNCTION SIXHUMP} computes the objective value. Lower and upper bounds of 0 and 1, respectively, are used to ensure that solution elements are nonnegative. Violations of the linear equality constraint are fixed by a simple repair strategy, implemented in \\texttt{FUNCTION SIXHUMP}: the sum of the solution elements is computed, and each element is divided by the sum, so that the sum of the new elements is 1. For the special case of all elements equal to 0, equal values are assigned to the solution elements.\n\n```plaintext\nproc ga seed = 555;\ncall SetEncoding('R3R2');\nnpoints = 3;\narray cvxhull[3,2] /nosym ( -2 0\n0 2\n2 -2);\n\n/* Objective function */\nfunction sixhump(selected[*],cvxhull[*,*],npoints);\n /* Function has global minimum value of -1.0316\n * at $x = (-0.0898 \\; 0.7126)$ and\n * $x = (0.0898 \\; -0.7126)$\n */\n array w[1] /nosym;\ncall dynamic_array(w,npoints);\narray x[2] /nosym;\ncall ReadMember(selected,1,w);\n /* make sure that weights add up to 1 */\n sum = 0;\ndo i = 1 to npoints;\n sum = sum + w[i];\n end;\n if sum=0 then do;\n sum = npoints;\n do i = 1 to npoints;\n w[i] = 1;\n end;\n end;\n /* re-normalize weights */\n do i = 1 to npoints;\n w[i] = w[i] / sum;\n end;\ncall WriteMember(selected,1,w);\n /* convert weights to $x$-coordinate form */\n x[1] = 0;\n x[2] = 0;\ndo i = 1 to npoints;\n x[1] = x[1] + w[i] * cvxhull[i,1];\nend;\n /* write out $x$ coordinates to second segment */\ncall WriteMember(selected,2,x);\n /* compute objective value */\n r = (4 - 2.1*x[1]**2 + x[1]**4/3)*x[1]**2 + x[1]*x[2] +\n```\n(-4 + 4*x[2]**2)*x[2]**2;\n return(r);\nendsub;\ncall SetObjFunc('sixhump',0);\narray lower[1] /nosym;\narray upper[1] /nosym;\ncall dynamic_array(lower, npoints);\ncall dynamic_array(upper, npoints);\ndo i = 1 to npoints;\n lower[i] = 0;\n upper[i] = 1;\nend;\ncall SetBounds(lower, upper, 1);\narray delta[3] /nosym (0.01 0.01 0.01);\ncall SetMut('delta', 'nchange', 1, 'delta', delta);\ncall SetMutProb(0.05);\ncall SetCross('Twopoint', 'alpha', 0.9);\ncall SetCrossProb(0.8);\ncall SetSel('tournament', 'size', 2);\ncall SetElite(3);\ncall Initialize('DEFAULT', 200);\ncall ContinueFor(200);\nrun;\n\nNote that this problem uses the standard genetic operators and default initialization, even though they generate solutions that violate the constraints. This is possible because all solutions are passed into the user objective function for evaluation, where they are repaired to fit the constraints. The output is shown in Output 4.2.1.\n\nOutput 4.2.1 Nonlinear Objective with Constraints Using Repair Mechanism\n\n<table>\n<thead>\n<tr>\n<th>PROC GA Optimum Values</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Objective</td>\n</tr>\n<tr>\n<td>-1.031617314</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Solution</th>\n<th>Segment</th>\n<th>Element</th>\n<th>Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>1</td>\n<td>0.2439660392</td>\n<td></td>\n</tr>\n<tr>\n<td>1</td>\n<td>2</td>\n<td>0.5561415112</td>\n<td></td>\n</tr>\n<tr>\n<td>1</td>\n<td>3</td>\n<td>0.1998924497</td>\n<td></td>\n</tr>\n<tr>\n<td>2</td>\n<td>1</td>\n<td>-0.088147179</td>\n<td></td>\n</tr>\n<tr>\n<td>2</td>\n<td>2</td>\n<td>0.712498123</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nThis objective function has a global minimum at \\(-1.0316\\), at two different points: \\((x_1, x_2) = (-0.0898, 0.7126)\\) and \\((x_1, x_2) = (0.0898, -0.7126)\\). The genetic algorithm can converge to either of these minima, depending on the random number seed set by the SEED= option.\nExample 4.3: Quadratic Objective with Linear Constraints, Using Bicriteria Approach\n\nThis example (Floudas and Pardalos 1992) illustrates the bicriteria approach to handling constraints. The problem has nine linear constraints and a quadratic objective function.\n\nMinimize\n\n\\[ f(x) = 5 \\sum_{i=1}^{4} x_i - 5 \\sum_{i=1}^{4} x_i^2 - \\sum_{i=5}^{13} x_i \\]\n\nsubject to\n\n\\begin{align*}\n2x_1 + 2x_2 + x_{10} + x_{11} & \\leq 10 \\\\\n2x_1 + 2x_3 + x_{10} + x_{12} & \\leq 10 \\\\\n2x_1 + 2x_3 + x_{11} + x_{12} & \\leq 10 \\\\\n-8x_1 + x_{10} & \\leq 0 \\\\\n-8x_2 + x_{11} & \\leq 0 \\\\\n-8x_3 + x_{12} & \\leq 0 \\\\\n-2x_4 - x_5 + x_{10} & \\leq 0 \\\\\n-2x_6 - x_7 + x_{11} & \\leq 0 \\\\\n-2x_8 - x_9 + x_{12} & \\leq 0 \\\\\n\\end{align*}\n\nand\n\n\\begin{align*}\n0 & \\leq x_i \\leq 1, \\quad i = 1, 2, \\ldots, 9 \\\\\n0 & \\leq x_i \\leq 100, \\quad i = 10, 11, 12 \\\\\n0 & \\leq x_{13} \\leq 1 \\\\\n\\end{align*}\n\nIn this example, the linear constraint coefficients are specified in the SAS data set lincon and passed to the GA procedure with the MATRIX1= option. The upper and lower bounds are specified in the bounds data set specified with a DATA1= option, which creates the array variables upper and lower, matching the variables in the data set.\n\n/* Input linear constraint matrix */\ndata lincon;\n input A1-A13 b;\n datalines;\n 2 2 0 0 0 0 0 0 0 0 1 1 0 0 10 \n 2 0 2 0 0 0 0 0 0 1 0 1 0 10 \n 2 0 2 0 0 0 0 0 0 0 1 1 0 10 \n -8 0 0 0 0 0 0 0 0 0 1 0 0 0 \n 0 -8 0 0 0 0 0 0 0 0 1 0 0 0 \n 0 0 -8 0 0 0 0 0 0 0 0 1 0 0 \n 0 0 0 -2 -1 0 0 0 1 0 0 0 \n 0 0 0 0 -2 -1 0 0 0 1 0 0 \n 0 0 0 0 0 -2 -1 0 0 1 0 0 \n 0 0 0 0 0 0 0 -2 -1 0 0 1 0 \n; /* Input lower and upper bounds */\ndata bounds;\ninput lower upper;\ndatalines;\n0 1\n0 1\n0 1\n0 1\n0 1\n0 1\n0 1\n0 1\n0 1\n0 100\n0 100\n0 100\n0 1\n;\n\nproc ga lastgen = out matrix1 = lincon seed = 555555\ndata1 = bounds novalidate = 3;\n\nNote also that the LASTGEN= option is used to designate a data set to store the final solution generation.\n\nIn the following statements, the solution encoding is specified, and a user function is defined and designated as the objective function.\n\n call SetEncoding('R13R3');\nnvar = 13;\nncon = 9;\nfunction quad(selected[*], matrix1[*,*], nvar, ncon);\n\n array x[1] /nosym;\n array r[3] /nosym;\n array violations[1] /nosym;\n call dynamic_array(x, nvar);\n call dynamic_array(violations, ncon);\n call ReadMember(selected,1,x);\n sum1 = 0;\n do i = 1 to 4;\n sum1 + x[i] - x[i] * x[i];\n end;\n sum2 = 0;\n do i = 5 to 13;\n sum2 + x[i];\nExample 4.3: Quadratic Objective with Linear Constraints, Using Bicriteria Approach\n\nend;\n\nobj = 5 * sum1 - sum2;\n\ncall EvaluateLC(matrix1,violations,sumvio,selected,1);\n\nr[1] = obj;\n\nr[2] = sumvio;\n\ncall WriteMember(selected,2,r);\n\nreturn(obj);\n\nendsub;\n\ncall SetObjFunc('quad',0);\n\nThe SetEncoding call specifies two real-valued segments. The first segment, R13, holds the 13 variables, and the second segment, R3, holds the two objective criteria and the marker for Pareto optimality. As described in the section “Defining an Objective Function” on page 130, the first parameter of the objective function is a numeric array that designates which member of the solution population is to be evaluated. When the quad function is called by the GA procedure during the optimization process, the $matrix1$, $nvar$, and $ncon$ parameters receive the values of the corresponding global variables; $nvar$ is set to the number of variables, and $ncon$ is set to the number of linear constraints. The function computes the original objective as the first objective criterion, and the magnitude of constraint violation as the second. With the first dynamic_array call, it allocates a working array, $x$, large enough to hold the number of variables, and a second array, violations, large enough to tabulate each constraint violation. The ReadMember call fills $x$ with the elements of the first segment of the solution, and then the function computes the original objective $f(x)$. The EvaluateLC call is used to compute the linear constraint violation. The objective and sum of the constraint violations are then stored in the array $r$, and written back to the second segment of the solution with the WriteMember call. Note that the third element of $r$ is not modified, because that element of the segment is used to store the Pareto-optimality mark, which cannot be determined until all the solutions have been evaluated.\n\nNext, a user routine is defined and designated to be an update routine. This routine is called once at each iteration, after all the solutions have been evaluated with the quad function. The following program illustrates this:\n\n```fortran\nsubroutine update(popsize);\n\n /* find pareto-optimal set */\n array minmax[3] /nosym (-1 -1 0);\n\n array results[1,1] /nosym;\n\n array scratch[1] /nosym;\n\n call dynamic_array(scratch, popsize);\n\n call dynamic_array(results,popsize,3);\n```\n/* read original and constraint objectives, stored in \n* solution segment 2, into array */\ncall GetSolutions(results,popsize,2);\n/* mark the pareto-optimal set */\ncall MarkPareto(scratch, npareto,results, minmax);\n/* transfer the results to the solution segment */\ndo i = 1 to popsize;\n results[i,3] = scratch[i];\nend;\n/* write updated segment 2 back into solution population */\ncall UpdateSolutions(results,popsize,2);\n/* Set Elite parameter to preserve the first 15 pareto-optimal \n* solutions */\nif npareto < 16 then\n call SetElite(npareto);\nelse\n call SetElite(15);\nendsub;\ncall SetUpdateRoutine('update');\n\nThis subroutine has one parameter, popsize, defined within the GA procedure, which is expected to be the \npopulation size. The working arrays results, scratch, and minmax are declared. The minmax array is to be \npassed to a MarkPareto call, and is initialized to specify that the first two elements (the original objective \nand constraint violation) are to be minimized and the third element is not to be considered. The results and \nscratch arrays are then dynamically allocated to the dimensions required by the population size.\n\nNext, the results array is filled with the second segment of the solution population, with the GetSolutions \ncall. The minmax and results arrays are passed as inputs to the MarkPareto call, which returns the number of \nPareto optimal solutions in the npareto variable. The MarkPareto call also sets the elements of the scratch \narray to 1 if the corresponding solution is Pareto-optimal, and to 0 otherwise. The next loop then records the \nresults in the scratch array in the third column of the results array, effectively marking the Pareto-optimal \nsolutions. The updated solution segments are written back to the population with the UpdateSolutions call.\n\nThe final step in the update routine is to set the elite selection parameter to guarantee the survival of at least a \nminimum of 15 of the fittest (Pareto-optimal) solutions through the selection process.\nWith the following statements, a routine is defined and designated as a fitness comparison routine with a SetCompareRoutine call. This routine works in combination with the update routine to evolve the solution population toward Pareto optimality and constraint satisfaction.\n\n```plaintext\nfunction paretocomp(selected[*]);\narray member1[3] /nosym;\narray member2[3] /nosym;\ncall ReadCompare(selected,2,1, member1);\ncall ReadCompare(selected,2,2, member2);\n/* if one member is in the pareto-optimal set\n * and the other is not, then it is the\n * most fit */\nif(member1[3] > member2[3]) then\n return(1);\nif(member2[3] > member1[3]) then\n return(-1);\n/* if both are in the pareto-optimal set, then\n * the one with the lowest constraint violation\n * is the most fit */\nif(member1[3] = 1) then do;\n if member1[2] <= member2[2] then\n return(1);\n return(-1);\nend;\n/* if neither is in the pareto-optimal set, then\n * take the one that dominates the other */\nif (member1[2] <= member2[2]) &\n (member1[1] <= member2[1]) then\n return(1);\n```\n\nif (member2[2] <= member1[2]) &\n (member2[1] <= member1[1]) then\n return(-1);\n\n/* if neither dominates, then consider fitness to be\n * the same */\nreturn( 0);\nendsub;\n\ncall SetSel('tournament', 'size', 2);\n\ncall SetCompareRoutine('paretocomp');\n\nThe PARETOCOMP subroutine is called in the selection process to compare the fitness of two competing solutions. The first parameter, selected, designates the two solutions to be compared.\n\nThe ReadCompare calls retrieve the second segments of the two solutions, where the objective criteria are stored, and writes the segments into the member1 and member2 arrays. The logic that follows first checks for the case where only one solution is Pareto optimal, and returns it. If both the solutions are Pareto optimal, then the one with the smallest constraint violation is chosen. If neither solution is Pareto optimal, then the dominant solution is chosen, if one exists. If neither solution is dominant, then no preference is indicated. After the function is defined, it is designated as a fitness comparison routine with the SetCompareRoutine call.\n\nNext, subroutines are defined and designated as user crossover and mutation operators:\n\n /* set up crossover parameters */\n subroutine Cross1(selected[*], alpha);\n call Cross(selected,1,'twopoint', alpha);\n endsub;\n\ncall SetCrossRoutine('Cross1',2,2);\nalpha = 0.5;\ncall SetCrossProb(0.8);\n\n /* set up mutation parameters */\n subroutine Mut1(selected[*], delta[*]);\n call Mutate(selected,1,'delta',delta,1);\n endsub;\ncall SetMutRoutine('Mut1');\n\narray delta[13] /nosym (.5 .5 .5 .5 .5 .5 .5 .5 10 10 10 .1);\n\ncall SetMutProb(0.05);\n\nThese routines execute the standard genetic operators _twopoint_ for crossover and _delta_ for mutation; see the section “Using Standard Genetic Operators and Objective Functions” on page 116 for a description of each. The _alpha_ and _delta_ variables defined in the procedure are passed as parameters to the user operators, and the crossover and mutation probabilities are set with the _SetCrossProb_ and _SetMutProb_ calls.\n\nAt this point, the GA procedure is directed to initialize the first population and begin the optimization process:\n\n```plaintext\n/* Initialize first population */\ncall SetBounds(lower, upper);\npopsize = 100;\ncall Initialize('DEFAULT', popsize);\ncall ContinueFor(500);\nrun;\n```\n\nFirst, the upper and lower bounds are established with values in the _lower_ and _upper_ array variables, which were set up by the DATA1= option in the PROC GA statement. The _SetBounds_ call sets the bounds for the first segment, which is the default if none is specified in the call. The desired population size of 100 is stored in the _popsize_ variable, so it will be passed to the _update_ subroutine as the _popsize_ parameter. The _Initialize_ call specifies the default initialization, which generates values randomly distributed between the lower and upper bounds for the first encoding segment. Since no bounds were specified for the second segment, it is filled with zeros. The _ContinueFor_ call sets the requested number of iterations to 500, and the RUN statement ends the GA procedure input and begins the optimization process. The output of the procedure is shown in _Output 4.3.1._\n\n**Output 4.3.1** Bicriteria Constraint Handling Example Output\n\n**Bicriteria Constraint Handling Example**\n\n**PROC GA Optimum Values**\n\n<table>\n<thead>\n<tr>\n<th>Objective</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>-14.99871988</td>\n</tr>\n</tbody>\n</table>\nThe minimum value of \\( f(x) \\) is \\(-15\\) at \\( x^* = (1, 1, 1, 1, 1, 1, 1, 3, 3, 1) \\).\n\n**References**\n\n\nSubject Index\n\nbicriteria comparison strategy, 135\nchoosing problem encoding, 83\nconstraints, 133\n bicriteria comparison strategy, 135\n direct comparison strategy, 134\n encoding strategy, 133\n penalty strategy, 134\n repair strategy, 134\ncontrolling selection process, 84\ncreating initial generation, 86\ncrossover operators, 116\ndefining\n fitness comparison routine, 124\n genetic operators, 126\n initialization routine, 131\n objective functions, 130\n update routine, 128\ndirect comparison strategy, 134\nduel selector, 133\ndirect comparison strategy, 134\nduel selector, 133\nevening strategies, 133\nfitness comparison routine\ndefining, 124\nGA procedure\ndebugging options, 102\n overview, 78\n program statements, 101\ngenetic algorithms, 78\ngenetic operators, 116\ndefining, 126\nheuristics, 133\ninitialization routine\ndefining, 131\ninitializing problem data, 81\nlocal optimizations, 133\nmonitoring progress, 87\nmultiple objectives, 135\nmultisegment encoding, 115\nmutation operators, 122\nobjective functions, 116, 124\ndefining, 130\noverview\n GA procedure, 78\npenalty strategy, 134\nprogram statements\n GA procedure, 101\nrepair strategy, 134\nreporting results, 87\nselection strategy, 132\nsetting crossover parameters, 85\nsetting mutation parameters, 86\nsetting objective function, 84\ntournament selector, 132\nupdate routine\ndefining, 128\nSyntax Index\n\nABORT statement\n GA program statements, 101\n\nDATAn= option\n PROC GA statement, 91\n\nDO statement\n GA program statements, 101\n\nFIRSTGEN= option\n PROC GA statement, 91\n\nGA procedure\n ContinueFor Call, 92\n Cross call, 93\n dynamic_array, 93\n EvaluateLC, 94\n GetDimensions, 95\n GetObjValues, 95\n GetSolutions Call, 95\n Initialize Call, 96\n MarkPareto Call, 97\n Mutate Call, 98\n Objective Call, 99\n PackBits Call, 100\n PROC GA statement, 90\n ReadChild Call, 102\n ReadCompare Call, 103\n ReadMember Call, 103\n ReadParent Call, 104\n ReEvaluate Call, 104\n SetBounds Call, 105\n SetCross Call, 105\n SetCrossProb Call, 106\n SetCrossRoutine Call, 107\n SetElite Call, 107\n SetEncoding Call, 107\n SetFinalize Call, 108\n SetMut Call, 108\n SetMutProb Call, 109\n SetMutRoutine Call, 105, 109\n SetObj Call, 110\n SetObjFunc Call, 110\n SetProperty Call, 111\n SetSel Call, 111\n SetUpdateRoutine Call, 112\n ShellSort Call, 112\n Shuffle Call, 113\n UnpackBits Function, 113\n UpdateSolutions Call, 113\n\nWriteChild Call, 114\nWriteMember Call, 114\n\nLASTGEN= option\n PROC GA statement, 91\n\nLIBRARY= option\n PROC GA statement, 91\n\nMATRIXn= option\n PROC GA statement, 92\n\nNITER= option\n PROC GA statement, 92\n\nNOVALIDATE= option\n PROC GA statement, 92\n\nNOVALIDATEWARNING= option\n PROC GA statement, 92\n\nOTHERWISE statement\n GA program statements, 102\n\nPROC GA statement, see GA procedure\n statement options, 90\n\nPUT statement\n GA program statements, 102\n\nSEED= option\n PROC GA statement, 92\n\nSELECT statement\n GA program statements, 102\n\nWHEN statement\n GA program statements, 102"}}},{"rowIdx":71,"cells":{"id":{"kind":"string","value":"0dc31022f095b4af7bd6403140d8a7e87aa8bed9"},"text":{"kind":"string","value":"Abstract\n\nWhile the OpenShift Container Platform Cluster administration guide is focused more on configuration, this guide will describe an overview of common daily maintenance tasks.\nTable of Contents\n\nCHAPTER 1. OVERVIEW ................................................................. 5\n\nCHAPTER 2. RUN-ONCE TASKS ....................................................... 6\n 2.1. NTP SYNCHRONIZATION .................................................. 6\n 2.2. ENTROPY ........................................................................ 6\n 2.3. CHECKING THE DEFAULT STORAGE CLASS ......................... 7\n\nCHAPTER 3. ENVIRONMENT HEALTH CHECKS ........................................ 9\n 3.1. CHECKING COMPLETE ENVIRONMENT HEALTH ................. 9\n Procedure ......................................................................... 9\n 3.2. CREATING ALERTS USING PROMETHEUS ......................... 9\n 3.3. HOST HEALTH ............................................................... 10\n 3.4. ROUTER AND REGISTRY HEALTH .................................... 11\n 3.5. NETWORK CONNECTIVITY ............................................ 11\n 3.5.1. Connectivity on master hosts .................................... 12\n 3.5.2. Connectivity on node instances ................................. 13\n Procedure .................................................................... 13\n 3.6. STORAGE .................................................................... 15\n 3.7. DOCKER STORAGE ....................................................... 16\n 3.8. API SERVICE STATUS ................................................... 17\n 3.9. CONTROLLER ROLE VERIFICATION .................................. 17\n 3.10. VERIFYING CORRECT MAXIMUM TRANSMISSION UNIT (MTU) SIZE\n Prerequisites .................................................................. 18\n\nCHAPTER 4. CREATING AN ENVIRONMENT-WIDE BACKUP .......................... 21\n 4.1. CREATING A MASTER HOST BACKUP .................................. 21\n Procedure ....................................................................... 22\n 4.2. CREATING A NODE HOST BACKUP .................................... 25\n Procedure ....................................................................... 25\n 4.3. BACKING UP REGISTRY CERTIFICATES ............................. 28\n Procedure ....................................................................... 28\n 4.4. BACKING UP OTHER INSTALLATION FILES ....................... 28\n Procedure ....................................................................... 28\n 4.5. BACKING UP APPLICATION DATA .................................... 29\n Procedure ....................................................................... 29\n 4.6. ETCD BACKUP ............................................................. 29\n 4.6.1. Backing up etcd ...................................................... 30\n 4.6.1.1. Backing up etcd configuration files .................. 30\n Procedure ............................................................... 30\n 4.6.1.2. Backing up etcd data ...................................... 31\n Prerequisites ......................................................... 31\n Procedure ............................................................... 32\n 4.7. BACKING UP A PROJECT ................................................ 33\n Procedure ....................................................................... 34\n 4.8. BACKING UP PERSISTENT VOLUME CLAIMS ....................... 35\n Procedure ....................................................................... 35\n\nCHAPTER 5. HOST-LEVEL TASKS ....................................................... 38\n 5.1. ADDING A HOST TO THE CLUSTER ..................................... 38\n 5.2. MASTER HOST TASKS ..................................................... 38\n 5.2.1. Deprecating a master host ....................................... 38\n 5.2.1.1. Creating a master host backup ......................... 38\n5.2.1.2. Backing up etcd\n\n5.2.1.2.1. Backing up etcd configuration files\n\n5.2.1.2.2. Backing up etcd data\n\n5.2.1.3. Deprecating a master host\n\n5.2.1.4. Removing an etcd host\n\n5.2.2. Creating a master host backup\n\n5.2.3. Restoring a master host backup\n\n5.3. NODE HOST TASKS\n\n5.3.1. Deprecating a node host\n\n5.3.1.1. Replacing a node host\n\n5.3.2. Creating a node host backup\n\n5.3.3. Restoring a node host backup\n\n5.3.4. Node maintenance and next steps\n\n5.4. ETCD TASKS\n\n5.4.1. etcd backup\n\n5.4.1.1. Backing up etcd configuration files\n\n5.4.1.2. Backing up etcd data\n\n5.4.2. Restoring etcd\n\n5.4.2.1. Restoring etcd v2 & v3 data\n\n5.4.2.2. Restoring etcd for v3\n\n5.4.3. Replacing an etcd host\n\n5.4.4. Scaling etcd\n\n5.4.5. Removing an etcd host\nCHAPTER 6. PROJECT-LEVEL TASKS ................................................................. 81\n 6.1. BACKING UP A PROJECT ................................................................. 81\n Procedure ......................................................................................... 81\n 6.2. RESTORING A PROJECT ................................................................. 82\n Procedure ......................................................................................... 82\n 6.2.1. Backing up persistent volume claims ...................................... 83\n Procedure ......................................................................................... 83\n 6.2.2. Restoring persistent volume claims ........................................ 84\n 6.2.2.1. Restoring files to an existing PVC ................................. 84\n Procedure ......................................................................................... 84\n 6.2.2.2. Restoring data to a new PVC .......................................... 85\n Procedure ......................................................................................... 85\n 6.2.3. Pruning images and containers ............................................. 86\n\nCHAPTER 7. DOCKER TASKS ................................................................. 87\n 7.1. INCREASING DOCKER STORAGE .................................................. 87\n 7.1.1. Evacuating the node ....................................................... 87\n Procedure ......................................................................................... 87\n 7.1.2. Increasing storage ........................................................... 87\n Prerequisites ....................................................................................... 88\n Procedure ......................................................................................... 88\n 7.1.3. Changing the storage backend ........................................... 90\n 7.1.3.1. Evacuating the node .................................................... 90\n 7.2. MANAGING DOCKER CERTIFICATES ......................................... 92\n 7.2.1. Installing a certificate authority certificate for external registries 92\n Procedure ......................................................................................... 92\n 7.2.2. Docker certificates backup ............................................... 93\n Procedure ......................................................................................... 93\n 7.2.3. Docker certificates restore ................................................ 94\n 7.3. MANAGING DOCKER REGISTRIES ............................................ 94\n 7.3.1. Docker search external registries ...................................... 94\n Procedure ......................................................................................... 95\n 7.3.2. Docker external registries whitelist and blacklist ............... 95\n Procedure ......................................................................................... 95\n 7.3.3. Secure registries ................................................................. 97\n 7.3.4. Insecure registries .............................................................. 97\n Procedure ......................................................................................... 97\n 7.3.5. Authenticated registries ...................................................... 98\n Procedure ......................................................................................... 98\n 7.3.6. ImagePolicy admission plug-in ......................................... 100\n Procedure ......................................................................................... 100\n 7.3.7. Import images from external registries .............................. 101\n Procedure ......................................................................................... 101\n 7.3.8. OpenShift Container Platform registry integration ............. 103\n 7.3.8.1. Connect the registry project with the cluster ............ 103\n Procedure ......................................................................................... 104\n\nCHAPTER 8. MANAGING CERTIFICATES ........................................... 106\n 8.1. CHANGING AN APPLICATION’S SELF-SIGNED CERTIFICATE TO CA-SIGNED CERTIFICATE 106\nCHAPTER 1. OVERVIEW\n\nThis section is built for OpenShift Container Platform administrators with a fresh installation.\n\nWhile the OpenShift Container Platform Cluster administration guide is focused more on configuration, this guide describes an overview of common daily maintenance tasks.\nCHAPTER 2. RUN-ONCE TASKS\n\nAfter installing OpenShift Container Platform, your system might need extra configuration to ensure your hosts consistently run smoothly.\n\nWhile these are classified as run-once tasks, you can perform any of these at any time if any circumstances change.\n\n2.1. NTP SYNCHRONIZATION\n\nNTP (Network Time Protocol) is for keeping hosts in sync with the world clock. Time synchronization is important for time sensitive operations, such as log keeping and time stamps, and is highly recommended for Kubernetes, which OpenShift Container Platform is built on. OpenShift Container Platform operations include etcd leader election, health checks for pods and some other issues, and helps prevent time skew problems.\n\nDepending on your instance, NTP might not be enabled by default. To verify that a host is configured to use NTP:\n\n```sh\n$ timedatectl\nLocal time: Thu 2017-12-21 14:58:34 UTC\nUniversal time: Thu 2017-12-21 14:58:34 UTC\nRTC time: Thu 2017-12-21 14:58:34\nTime zone: Etc/UTC (UTC, +0000)\nNTP enabled: yes\nNTP synchronized: yes\nRTC in local TZ: no\nDST active: n/a\n```\n\nIf both NTP enabled and NTP synchronized are yes, then NTP synchronization is active.\n\nIf no, install and enable the ntp or chrony RPM package.\n\nFor NTP:\n\n```sh\n# timedatectl set-ntp true\n```\n\nFor chrony:\n\n```sh\n# yum install chrony\n# systemctl enable chronyd --now\n```\n\n**IMPORTANT**\n\nTime synchronization should be enabled on all hosts in the cluster, whether using NTP or any other method.\n\nFor more information about the `timedatectl` command, timezones, and clock configuration, see Configuring the date and time and UTC, Timezones, and DST.\n\n2.2. ENTROPY\n\nOpenShift Container Platform uses entropy to generate random numbers for objects such as IDs or SSL\ntraffic. These operations wait until there is enough entropy to complete the task. Without enough entropy, the kernel is not able to generate these random numbers with sufficient speed, which can lead to timeouts and the refusal of secure connections.\n\nTo check available entropy:\n\n```\n$ cat /proc/sys/kernel/random/entropy_avail\n2683\n```\n\nThe available entropy should be verified on all node hosts in the cluster. Ideally, this value should be above 1000.\n\n**NOTE**\n\nRed Hat recommends monitoring this value and issuing an alert if the value is under 800.\n\nAlternatively, you can use the `rngtest` command to check not only the available entropy, but if your system can feed enough entropy as well:\n\n```\n$ cat /dev/random | rngtest -c 100\n```\n\nThe `rngtest` command is available from the *rng-tools*\n\nIf the above takes around 30 seconds to complete, then there is not enough entropy available.\n\nDepending on your environment, entropy can be increased in multiple ways. For more information, see the following blog post: https://developers.redhat.com/blog/2017/10/05/entropy-rhel-based-cloud-instances/.\n\nGenerally, you can increase entropy by installing the *rng-tools* package and enabling the *rngd* service:\n\n```\n# yum install rng-tools\n# systemctl enable --now rngd\n```\n\nOnce the *rngd* service has started, entropy should increase to a sufficient level.\n\n### 2.3. CHECKING THE DEFAULT STORAGE CLASS\n\nFor proper functionality of dynamically provisioned persistent storage, the default storage class needs to be defined. During the installation, this default storage class is defined for common cloud providers, such as Amazon Web Services (AWS), Google Cloud Platform (GCP), and more.\n\nTo verify that the default storage class is defined:\n\n```\n$ oc get storageclass\nNAME TYPE\nssd kubernetes.io/gce-pd\nstandard (default) kubernetes.io/gce-pd\n```\n\nThe above output is taken from an OpenShift Container Platform instance running on GCP, where two kinds of persistent storage are available: standard (HDD) and SSD. Notice the standard storage class is configured as the default. If there is no storage class defined, or none is set as a default, see the\nDynamic Provisioning and Creating Storage Classes section for instructions on how to set up a storage class as suggested.\nCHAPTER 3. ENVIRONMENT HEALTH CHECKS\n\nThis topic contains steps to verify the overall health of the OpenShift Container Platform cluster and the various components, as well as describing the intended behavior.\n\nKnowing the verification process for the various components is the first step to troubleshooting issues. If experiencing issues, you can use the checks provided in this section to diagnose any problems.\n\n3.1. CHECKING COMPLETE ENVIRONMENT HEALTH\n\nTo verify the end-to-end functionality of an OpenShift Container Platform cluster, build and deploy an example application.\n\nProcedure\n\n1. Create a new project named `validate`, as well as an example application from the `cakephp-mysql-example` template:\n\n ```bash\n $ oc new-project validate\n $ oc new-app cakephp-mysql-example\n ```\n\n You can check the logs to follow the build:\n\n ```bash\n $ oc logs -f bc/cakephp-mysql-example\n ```\n\n2. Once the build is complete, two pods should be running: a database and an application:\n\n ```bash\n $ oc get pods\n NAME READY STATUS RESTARTS AGE\n cakephp-mysql-example-1-build 0/1 Completed 0 1m\n cakephp-mysql-example-2-247xm 1/1 Running 0 39s\n mysql-1-hbk46 1/1 Running 0 1m\n ```\n\n3. Visit the application URL. The Cake PHP framework welcome page should be visible. The URL should have the following format `cakephp-mysql-example-validate.<app_domain>`.\n\n4. Once the functionality has been verified, the `validate` project can be deleted:\n\n ```bash\n $ oc delete project validate\n ```\n\n All resources within the project will be deleted as well.\n\n3.2. CREATING ALERTS USING PROMETHEUS\n\nYou can integrate OpenShift Container Platform with Prometheus to create visuals and alerts to help diagnose any environment issues before they arise. These issues can include if a node goes down, if a pod is consuming too much CPU or memory, and more.\n\nSee the Prometheus on OpenShift Container Platform section in the Installation and configuration guide for more information.\nIMPORTANT\n\nPrometheus on OpenShift Container Platform is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs), might not be functionally complete, and Red Hat does not recommend to use them for production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.\n\nFor more information on Red Hat Technology Preview features support scope, see https://access.redhat.com/support/offerings/techpreview/.\n\n3.3. HOST HEALTH\n\nTo verify that the cluster is up and running, connect to a master instance, and run the following:\n\n$ oc get nodes\n\n<table>\n<thead>\n<tr>\n<th>NAME</th>\n<th>STATUS</th>\n<th>AGE</th>\n<th>VERSION</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ocp-infra-node-1clj</td>\n<td>Ready</td>\n<td>1h</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ocp-infra-node-86qr</td>\n<td>Ready</td>\n<td>1h</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ocp-infra-node-g8qw</td>\n<td>Ready</td>\n<td>1h</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ocp-master-94zd</td>\n<td>Ready,SchedulingDisabled</td>\n<td>1h</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ocp-master-gjkm</td>\n<td>Ready,SchedulingDisabled</td>\n<td>1h</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ocp-master-wc8w</td>\n<td>Ready,SchedulingDisabled</td>\n<td>1h</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ocp-node-c5dg</td>\n<td>Ready</td>\n<td>1h</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ocp-node-ghxn</td>\n<td>Ready</td>\n<td>1h</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ocp-node-w135</td>\n<td>Ready</td>\n<td>1h</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n</tbody>\n</table>\n\nThe above cluster example consists of three master hosts, three infrastructure node hosts, and three node hosts. All of them are running. All hosts in the cluster should be visible in this output.\n\nThe **Ready** status means that master hosts can communicate with node hosts and that the nodes are ready to run pods (excluding the nodes in which scheduling is disabled).\n\nBefore you run etcd commands, source the `etcd.conf` file:\n\n```bash\n# source /etc/etcd/etcd.conf\n```\n\nYou can check the basic etcd health status from any master instance with the `etcdctl` command:\n\n```bash\n# etcdctl --cert-file=$ETCD_PEER_CERT_FILE --key-file=$ETCD_PEER_KEY_FILE --ca-file=/etc/etcd/ca.crt --endpoints=$ETCD_LISTEN_CLIENT_URLS cluster-health\n```\n\n```\nmember 59df5107484b84df is healthy: got healthy result from https://10.156.0.5:2379\nmember 6df7221a03f65299 is healthy: got healthy result from https://10.156.0.6:2379\nmember fea6dfedf3eeecfa3 is healthy: got healthy result from https://10.156.0.9:2379\ncluster is healthy\n```\n\nHowever, to get more information about etcd hosts, including the associated master host:\n\n```bash\n# etcdctl --cert-file=$ETCD_PEER_CERT_FILE --key-file=$ETCD_PEER_KEY_FILE --ca-file=/etc/etcd/ca.crt --endpoints=$ETCD_LISTEN_CLIENT_URLS member list\n```\n\n```\n295750b7103123e0: name=ocp-master-zh8d peerURLs=https://10.156.0.7:2380\nclientURLs=https://10.156.0.7:2379 isLeader=true\nb097a72f2610ae2e5: name=ocp-master-qcg3 peerURLs=https://10.156.0.7:2380\n```\nclientURLs=https://10.156.0.11:2379 isLeader=false\nfea6dfe9d3ee83a: name=ocp-master-j338 peerURLs=https://10.156.0.9:2380\nclientURLs=https://10.156.0.9:2379 isLeader=false\n\nAll etcd hosts should contain the master host name if the etcd cluster is co-located with master services, or all etcd instances should be visible if etcd is running separately.\n\n**NOTE**\n\n`etcdctl2` is an alias for the `etcdctl` tool that contains the proper flags to query the etcd cluster in v2 data model, as well as, `etcdctl3` for v3 data model.\n\n### 3.4. ROUTER AND REGISTRY HEALTH\n\nTo check if a router service is running:\n\n```\n$ oc -n default get deploymentconfigs/router\n```\n\n```\nNAME REVISION DESIRED CURRENT TRIGGERED BY\nrouter 1 3 3 config\n```\n\nThe values in the **DESIRED** and **CURRENT** columns should match the number of nodes hosts.\n\nUse the same command to check the registry status:\n\n```\n$ oc -n default get deploymentconfigs/docker-registry\n```\n\n```\nNAME REVISION DESIRED CURRENT TRIGGERED BY\ndocker-registry 1 3 3 config\n```\n\n**NOTE**\n\nMultiple running instances of the container registry require backend storage supporting writes by multiple processes. If the chosen infrastructure provider does not contain this ability, running a single instance of a container registry is acceptable.\n\nTo verify that all pods are running and on which hosts:\n\n```\n$ oc -n default get pods -o wide\n```\n\n```\nNAME READY STATUS RESTARTS AGE IP NODE\ndocker-registry-1-54nhl 1/1 Running 0 2d 172.16.2.3 ocp-infra-node-tl47\ndocker-registry-1-jsm2t 1/1 Running 0 2d 172.16.8.2 ocp-infra-node-62rc\ndocker-registry-1-qbt4g 1/1 Running 0 2d 172.16.14.3 ocp-infra-node-xrtz\nregistry-console-2-gbhcz 1/1 Running 0 2d 172.16.8.4 ocp-infra-node-62rc\nrouter-1-6zhf8 1/1 Running 0 2d 10.156.0.4 ocp-infra-node-62rc\nrouter-1-ffq4g 1/1 Running 0 2d 10.156.0.10 ocp-infra-node-tl47\nrouter-1-zqxbl 1/1 Running 0 2d 10.156.0.8 ocp-infra-node-xrtz\n```\n\n**NOTE**\n\nIf OpenShift Container Platform is using an external container registry, the internal registry service does not need to be running.\n\n### 3.5. NETWORK CONNECTIVITY\nNetwork connectivity has two main networking layers: the cluster network for node interaction, and the software defined network (SDN) for pod interaction. OpenShift Container Platform supports multiple network configurations, often optimized for a specific infrastructure provider.\n\n**NOTE**\n\nDue to the complexity of networking, not all verification scenarios are covered in this section.\n\n### 3.5.1. Connectivity on master hosts\n\n**etcd and master hosts**\n\nMaster services keep their state synchronized using the etcd key-value store. Communication between master and etcd services is important, whether those etcd services are collocated on master hosts, or running on hosts designated only for the etcd service. This communication happens on TCP ports 2379 and 2380. See the Host health section for methods to check this communication.\n\n**SkyDNS**\n\nSkyDNS provides name resolution of local services running in OpenShift Container Platform. This service uses TCP and UDP port 8053.\n\nTo verify the name resolution:\n\n```bash\n$ dig +short docker-registry.default.svc.cluster.local\n```\n\nIf the answer matches the output of the following, SkyDNS service is working correctly:\n\n```bash\n$ oc get svc/docker-registry -n default\n```\n\n<table>\n<thead>\n<tr>\n<th>NAME</th>\n<th>CLUSTER-IP</th>\n<th>EXTERNAL-IP</th>\n<th>PORT(S)</th>\n<th>AGE</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>docker-registry</td>\n<td>172.30.150.7</td>\n<td><none></td>\n<td>5000/TCP</td>\n<td>3d</td>\n</tr>\n</tbody>\n</table>\n\n**API service and web console**\n\nBoth the API service and web console share the same port, usually TCP 8443 or 443, depending on the setup. This port needs to be available within the cluster and to everyone who needs to work with the deployed environment. The URLs under which this port is reachable may differ for internal cluster and for external clients.\n\nIn the following example, the `https://internal-master.example.com:443` URL is used by the internal cluster, and the `https://master.example.com:443` URL is used by external clients. On any node host:\n\n```bash\n$ curl https://internal-master.example.com:443/version\n```\n\n```json\n{\n \"major\": \"1\",\n \"minor\": \"6\",\n \"gitVersion\": \"v1.6.1+5115d708d7\",\n \"gitCommit\": \"fff65cf\",\n \"gitTreeState\": \"clean\",\n \"buildDate\": \"2017-10-11T22:44:25Z\",\n \"goVersion\": \"go1.7.6\",\n}\n```\n\"compiler\": \"gc\",\n\"platform\": \"linux/amd64\"\n}\n\nThis must be reachable from client’s network:\n\n```bash\n$ curl -k https://master.example.com:443/healthz\nok\n```\n\n### 3.5.2. Connectivity on node instances\n\nThe SDN connecting pod communication on nodes uses **UDP** port **4789** by default.\n\nTo verify node host functionality, create a new application. The following example ensures the node reaches the docker registry, which is running on an infrastructure node:\n\n**Procedure**\n\n1. Create a new project:\n\n ```bash\n $ oc new-project sdn-test\n ```\n\n2. Deploy an httpd application:\n\n ```bash\n $ oc new-app centos/httpd-24-centos7~https://github.com/sclorg/httpd-ex\n ```\n\n Wait until the build is complete:\n\n ```bash\n $ oc get pods\n NAME READY STATUS RESTARTS AGE\n httpd-ex-1-205hz 1/1 Running 0 34s\n httpd-ex-1-build 0/1 Completed 0 1m\n ```\n\n3. Connect to the running pod:\n\n ```bash\n $ oc rsh po/<pod-name>\n ```\n\n For example:\n\n ```bash\n $ oc rsh po/httpd-ex-1-205hz\n ```\n\n4. Check the **healthz** path of the internal registry service:\n\n ```bash\n $ curl -kv https://docker-registry.default.svc.cluster.local:5000/healthz\n * About to connect() to docker-registry.default.svc.cluster.local port 5000 (#0)\n * Trying 172.30.150.7...\n * Connected to docker-registry.default.svc.cluster.local (172.30.150.7) port 5000 (#0)\n * Initializing NSS with certpath: sql:/etc/pki/nssdb\n * skipping SSL peer certificate verification\n * SSL connection using TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256\n * Server certificate:\n * subject: CN=172.30.150.7\n * start date: Nov 30 17:21:51 2017 GMT\n ```\nThe HTTP/1.1 200 OK response means the node is correctly connecting.\n\n5. **Clean up the test project:**\n\n $ oc delete project sdn-test\n project \"sdn-test\" deleted\n\n6. **The node host is listening on TCP port 10250.** This port needs to be reachable by all master hosts on any node, and if monitoring is deployed in the cluster, the infrastructure nodes must have access to this port on all instances as well. Broken communication on this port can be detected with the following command:\n\n $ oc get nodes\n NAME STATUS AGE VERSION\n ocp-infra-node-1clj Ready 4d v1.6.1+5115d708d7\n ocp-infra-node-86qr Ready 4d v1.6.1+5115d708d7\n ocp-infra-node-g8qw Ready 4d v1.6.1+5115d708d7\n ocp-master-94zd Ready,SchedulingDisabled 4d v1.6.1+5115d708d7\n ocp-master-gjkm Ready,SchedulingDisabled 4d v1.6.1+5115d708d7\n ocp-master-wc8w Ready,SchedulingDisabled 4d v1.6.1+5115d708d7\n ocp-node-c5dg Ready 4d v1.6.1+5115d708d7\n ocp-node-ghxn Ready 4d v1.6.1+5115d708d7\n ocp-node-w135 NotReady 4d v1.6.1+5115d708d7\n\n In the output above, the node service on the ocp-node-w135 node is not reachable by the master services, which is represented by its NotReady status.\n\n7. **The last service is the router, which is responsible for routing connections to the correct services running in the OpenShift Container Platform cluster.** Routers listen on TCP ports **80** and **443** on infrastructure nodes for ingress traffic. Before routers can start working, DNS must be configured:\n\n $ dig *.apps.example.com\n\n ;; global options: +cmd\n ;; Got answer:\nThe IP address, in this case `35.xx.xx.92`, should be pointing to the load balancer distributing ingress traffic to all infrastructure nodes. To verify the functionality of the routers, check the registry service once more, but this time from outside the cluster:\n\n```\n$ curl -kv https://docker-registry-default.apps.example.com/healthz\n* Trying 35.xx.xx.92...\n* TCP_NODELAY set\n* Connected to docker-registry-default.apps.example.com (35.xx.xx.92) port 443 (#0)\n...< HTTP/2 200\n< cache-control: no-cache\n< content-type: text/plain; charset=utf-8\n< content-length: 0\n< date: Tue, 05 Dec 2017 15:13:27 GMT\n<\n* Connection #0 to host docker-registry-default.apps.example.com left intact\n```\n\n### 3.6. STORAGE\n\nMaster instances need at least 40 GB of hard disk space for the `/var` directory. Check the disk usage of a master host using the `df` command:\n\n```\n$ df -hT\nFilesystem Type Size Used Avail Use% Mounted on\n/dev/sda1 xfs 45G 2.8G 43G 7% /\ndevtmpfs devtmpfs 3.6G 0 3.6G 0% /dev\ntmpfs tmpfs 3.6G 63M 3.6G 2% /run\ntmpfs tmpfs 3.6G 0 3.6G 0% /sys/fs/cgroup\ntmpfs tmpfs 732M 0 732M 0% /run/user/1000\ntmpfs tmpfs 732M 0 732M 0% /run/user/0\n```\n\nNode instances need at least 15 GB space for the `/var` directory, and at least another 15 GB for Docker storage (`/var/lib/docker` in this case). Depending on the size of the cluster and the amount of ephemeral storage desired for pods, a separate partition should be created for `/var/lib/origin/openshift.local.volumes` on the nodes.\nPersistent storage for pods should be handled outside of the instances running the OpenShift Container Platform cluster. Persistent volumes for pods can be provisioned by the infrastructure provider, or with the use of container native storage or container ready storage.\n\n### 3.7. DOCKER STORAGE\n\nDocker Storage can be backed by one of two options. The first is a thin pool logical volume with device mapper, the second, since Red Hat Enterprise Linux version 7.4, is an overlay2 file system. The overlay2 file system is generally recommended due to the ease of setup and increased performance.\n\nThe Docker storage disk is mounted as `/var/lib/docker` and formatted with `xfs` file system. Docker storage is configured to use overlay2 filesystem:\n\n```sh\n$ cat /etc/sysconfig/docker-storage\nDOCKER_STORAGE_OPTIONS=\"--storage-driver overlay2\"\n```\n\nTo verify this storage driver is used by Docker:\n\n```sh\n# docker info\nContainers: 4\nRunning: 4\nPaused: 0\nStopped: 0\nImages: 4\nServer Version: 1.12.6\nStorage Driver: overlay2\nBacking Filesystem: xfs\nLogging Driver: journald\nCgroup Driver: systemd\nPlugins:\nVolume: local\nNetwork: overlay host bridge null\nAuthorization: rhel-push-plugin\nSwarm: inactive\nRuntimes: docker-runc runc\nDefault Runtime: docker-runc\nSecurity Options: seccomp selinux\nKernel Version: 3.10.0-693.11.1.el7.x86_64\nOperating System: Employee SKU\nOSType: linux\nArchitecture: x86_64\nNumber of Docker Hooks: 3\nCPUs: 2\n```\n3.8. API SERVICE STATUS\n\nThe OpenShift API service, `atomic-openshift-master-api.service`, runs on all master instances. To see the status of the service:\n\n```\n$ systemctl status atomic-openshift-master-api.service\n● atomic-openshift-master-api.service - Atomic OpenShift Master API\n Loaded: loaded (/usr/lib/systemd/system/atomic-openshift-master-api.service; enabled; vendor preset: disabled)\n Active: active (running) since Thu 2017-11-30 11:40:19 EST; 5 days ago\n Docs: https://github.com/openshift/origin\n Main PID: 30047 (openshift)\n Memory: 65.0M\n CGroup: /system.slice/atomic-openshift-master-api.service\n └─ 30047 /usr/bin/openshift start master api --config=/etc/origin/master/ma...\n```\n\nThe API service exposes a health check, which can be queried externally with:\n\n```\n$ curl -k https://master.example.com/healthz\nok\n```\n\n3.9. CONTROLLER ROLE VERIFICATION\n\nThe OpenShift Container Platform controller service, `atomic-openshift-master-controllers.service`, is available across all master hosts. The service runs in active/passive mode, meaning it should only be running on one master at any time.\n\nThe OpenShift Container Platform controllers execute a procedure to choose which host runs the service. The current running value is stored in an annotation in a special `configmap` stored in the `kube-system` project.\n\nVerify the master host running the `atomic-openshift-master-controllers` service as a `cluster-admin` user:\n\n```\n$ oc get -n kube-system cm openshift-master-controllers -o yaml\n```\nThe command outputs the current master controller in the `control-plane.alpha.kubernetes.io/leader` annotation, within the `holderIdentity` property as:\n\n```\nmaster-<hostname>-<ip>-<8_random_characters>\n```\n\nFind the hostname of the master host by filtering the output using the following:\n\n```\n$ oc get -n kube-system cm openshift-master-controllers -o json | jq -r '.metadata.annotations[] | fromjson.holderIdentity | match(\"^master-(.*)-[0-9.]*-[0-9a-z]{8}$\") | .captures[0].string'\n```\n\n```\nose-master-0.example.com\n```\n\n### 3.10. VERIFYING CORRECT MAXIMUM TRANSMISSION UNIT (MTU) SIZE\n\nVerifying the maximum transmission unit (MTU) prevents a possible networking misconfiguration that can masquerade as an SSL certificate issue.\n\nWhen a packet is larger than the MTU size that is transmitted over HTTP, the physical network router is able to break the packet into multiple packets to transmit the data. However, when a packet is larger than the MTU size that is transmitted over HTTPS, the router is forced to drop the packet.\n\nInstallation produces certificates that provide secure connections to multiple components that include:\n\n- master hosts\n- node hosts\n- infrastructure nodes\n- registry\n- router\n\nThese certificates can be found within the `/etc/origin/master` directory for the master nodes and `/etc/origin/node` directory for the infra and app nodes.\n\nAfter installation, you can verify connectivity to the `REGISTRY_OPENShift_SERVER_ADDR` using the process outlined in the Network connectivity section.\n\n**Prerequisites**\n1. From a master host, get the HTTPS address:\n\n```\n$ oc get dc docker-registry -o jsonpath='{.spec.template.spec.containers[?(@.name==\"OPENSHIFT_DEFAULT_REGISTRY\")]}.env[?(@.name==\"value\")]\"n\"'\ndocker-registry.default.svc:5000\n```\n\nThe above gives the output of `docker-registry.default.svc:5000`.\n\n2. Append `/healthz` to the value given above, use it to check on all hosts (master, infrastructure, node):\n\n```\n$ curl -v https://docker-registry.default.svc:5000/healthz\n```\n\nThe above example output shows the MTU size being used to ensure the SSL connection is correct. The attempt to connect is successful, followed by connectivity being established and completes with initializing the NSS with the certpath and all the server certificate information regarding the `docker-registry`.\n\nAn improper MTU size results in a timeout:\n\n```\n$ curl -v https://docker-registry.default.svc:5000/healthz\n```\n\nThe above example shows that the connection is established, but it cannot finish initializing NSS with certpath. The issue deals with improper MTU size set within the `/etc/origin/node/node-config.yaml` file.\nTo fix this issue, adjust the MTU size within the `/etc/origin/node/node-config.yaml` to 50 bytes smaller than the MTU size being used by the OpenShift SDN Ethernet device.\n\n3. View the MTU size of the desired Ethernet device (i.e. `eth0`):\n\n ```bash\n $ ip link show eth0\n 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP\n mode DEFAULT qlen 1000\n link/ether fa:16:3e:92:6a:86 brd ff:ff:ff:ff:ff:ff\n The above shows MTU set to 1500.\n ```\n\n4. To change the MTU size, modify the `/etc/origin/node/node-config.yaml` file and set a value that is 50 bytes smaller than output provided by the `ip` command.\n For example, if the MTU size is set to 1500, adjust the MTU size to 1450 within the `/etc/origin/node/node-config.yaml` file:\n\n ```yaml\n networkConfig:\n mtu: 1450\n ```\n\n5. Save the changes and reboot the node:\n\n **NOTE**\n \n You must change the MTU size on all masters and nodes that are part of the OpenShift Container Platform SDN. Also, the MTU size of the tun0 interface must be the same across all nodes that are part of the cluster.\n\n6. Once the node is back online, confirm the issue no longer exists by re-running the original `curl` command.\n\n ```bash\n $ curl -v https://docker-registry.default.svc:5000/healthz\n ```\n\n If the timeout persists, continue to adjust the MTU size in increments of 50 bytes and repeat the process.\nCHAPTER 4. CREATING AN ENVIRONMENT-WIDE BACKUP\n\nCreating an environment-wide backup involves copying important data to assist with restoration in the case of crashing instances, or corrupt data. After backups have been created, they can be restored onto a newly installed version of the relevant component.\n\nIn OpenShift Container Platform, you can back up, saving state to separate storage, at the cluster level. The full state of an environment backup includes:\n\n- Cluster data files\n- etcd data on each master\n- API objects\n- Registry storage\n- Volume storage\n\nPerform a back up on a regular basis to prevent data loss.\n\nIMPORTANT\n\nThe following process describes a generic way of backing up applications and the OpenShift Container Platform cluster. It cannot take into account custom requirements. Use these steps as a foundation for a full backup and restoration procedure for your cluster. You must take all necessary precautions to prevent data loss.\n\nBackup and restore is not guaranteed. You are responsible for backing up your own data.\n\n4.1. CREATING A MASTER HOST BACKUP\n\nPerform this backup process before any change to the OpenShift Container Platform infrastructure, such as a system update, upgrade, or any other significant modification. Back up data regularly to ensure that recent data is available if a failure occurs.\n\nOpenShift Container Platform files\n\nThe master instances run important services, such as the API, controllers. The /etc/origin/master directory stores many important files:\n\n- The configuration, the API, controllers, services, and more\n- Certificates generated by the installation\n- All cloud provider-related configuration\n- Keys and other authentication files, such as htpasswd if you use htpasswd\n- And more\n\nYou can customize OpenShift Container Platform services, such as increasing the log level or using proxies. The configuration files are stored in the /etc/sysconfig directory.\n\nBecause the masters are also nodes, back up the entire /etc/origin directory.\n**Procedure**\n\n**IMPORTANT**\n\nYou must perform the following steps on each master node.\n\n1. Create a backup of the master host configuration files:\n\n ```\n $ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n $ sudo mkdir -p ${MYBACKUPDIR}/etc/sysconfig\n $ sudo cp -aR /etc/origin ${MYBACKUPDIR}/etc\n $ sudo cp -aR /etc/sysconfig/atomic-* ${MYBACKUPDIR}/etc/sysconfig/\n ```\n\n **NOTE**\n \n The configuration file is stored in the `/etc/sysconfig/atomic-openshift-master-api`, and `/etc/sysconfig/atomic-openshift-master-controllers` directories.\n\n **WARNING**\n \n The `/etc/origin/master/ca.serial.txt` file is generated on only the first master listed in the Ansible host inventory. If you deprecate the first master host, copy the `/etc/origin/master/ca.serial.txt` file to the rest of master hosts before the process.\n\n2. Other important files that need to be considered when planning a backup include:\n\n<table>\n<thead>\n<tr>\n<th>File</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>/etc/cni/*</code></td>\n<td>Container Network Interface configuration (if used)</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/iptables</code></td>\n<td>Where the <code>iptables</code> rules are stored</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/docker-storage-setup</code></td>\n<td>The input file for <code>container-storage-setup</code> command</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/docker</code></td>\n<td>The <code>docker</code> configuration file</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/docker-network</code></td>\n<td><code>docker</code> networking configuration (i.e. MTU)</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/docker-storage</code></td>\n<td><code>docker</code> storage configuration (generated by <code>container-storage-setup</code>)</td>\n</tr>\n<tr>\n<td><code>/etc/dnsmasq.conf</code></td>\n<td>Main configuration file for <code>dnsmasq</code></td>\n</tr>\n<tr>\n<td>/etc/dnsmasq.d/*</td>\n<td>Different <strong>dnsmasq</strong> configuration files</td>\n</tr>\n<tr>\n<td>---------------------------</td>\n<td>-------------------------------------------</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/flanneld</td>\n<td><strong>flannel</strong> configuration file (if used)</td>\n</tr>\n<tr>\n<td>/etc/pki/ca-trust/source/anchors/</td>\n<td>Certificates added to the system (i.e. for external registries)</td>\n</tr>\n</tbody>\n</table>\n\nCreate a backup of those files:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo mkdir -p $MYBACKUPDIR/etc/sysconfig\n$ sudo mkdir -p $MYBACKUPDIR/etc/pki/ca-trust/source/anchors\n$ sudo cp -aR /etc/sysconfig/* {iptables, docker-*, flanneld} ${MYBACKUPDIR}/etc/sysconfig/\n$ sudo cp -aR /etc/dnsmasq* /etc/cni ${MYBACKUPDIR}/etc/\n$ sudo cp -aR /etc/pki/ca-trust/source/anchors/* ${MYBACKUPDIR}/etc/pki/ca-trust/source/anchors/\n```\n\n3. If a package is accidentally removed or you need to restore a file that is included in an **rpm** package, having a list of **rhel** packages installed on the system can be useful.\n\n**NOTE**\n\nIf you use Red Hat Satellite features, such as content views or the facts store, provide a proper mechanism to reinstall the missing packages and a historical data of packages installed in the systems.\n\nTo create a list of the current **rhel** packages installed in the system:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo mkdir -p $MYBACKUPDIR\n$ rpm -qa | sort | sudo tee $MYBACKUPDIR/packages.txt\n```\n\n4. If you used the previous steps, the following files are present in the backup directory:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo find $MYBACKUPDIR -mindepth 1 -type f -printf '%P\n' etc/sysconfig/atomic-openshift-master\netc/sysconfig/atomic-openshift-master-api\netc/sysconfig/atomic-openshift-master-controllers\netc/sysconfig/atomic-openshift-node\netc/sysconfig/flanneld\netc/sysconfig/iptables\netc/sysconfig/docker-network\netc/sysconfig/docker-storage\netc/sysconfig/docker-storage-setup\netc/sysconfig/docker-storage-setup.rpmnew\netc/origin/master/ca.crt\netc/origin/master/ca.key\netc/origin/master/ca.serial.txt\netc/origin/master/ca-bundle.crt\netc/origin/master/master.proxy-client.crt\netc/origin/master/master.proxy-client.key\netc/origin/master/service-signer.crt\netc/origin/master/service-signer.key\netc/origin/master/serviceaccounts.private.key\netc/origin/master/serviceaccounts.public.key\netc/origin/master/openshift-master.crt\netc/origin/master/openshift-master.key\netc/origin/master/openshift-master.kubeconfig\netc/origin/master/master.server.crt\netc/origin/master/master.server.key\netc/origin/master/master.kubelet-client.crt\netc/origin/master/master.kubelet-client.key\netc/origin/master/admin.crt\netc/origin/master/admin.key\netc/origin/master/admin.kubeconfig\netc/origin/master/etcd.server.crt\netc/origin/master/etcd.server.key\netc/origin/master/etcd-client.key\netc/origin/master/etcd-client.csr\netc/origin/master/etcd-client.crt\netc/origin/master/etcd-ca.crt\netc/origin/master/policy.json\netc/origin/master/scheduler.json\netc/origin/master/htpasswd\netc/origin/master/session-secrets.yaml\netc/origin/master/openshift-router.crt\netc/origin/master/openshift-router.key\netc/origin/master/registry.crt\netc/origin/master/registry.key\netc/origin/master/master-config.yaml\netc/origin/generated-configs/master-master-1.example.com/master.server.crt\n...[OUTPUT OMITTED]...\netc/origin/cloudprovider/openstack.conf\netc/origin/node/system:node:master-0.example.com.crt\netc/origin/node/system:node:master-0.example.com.key\netc/origin/node/ca.crt\netc/origin/node/system:node:master-0.example.com.kubeconfig\netc/origin/node/server.crt\netc/origin/node/server.key\netc/origin/node/node-dnsmasq.conf\netc/origin/node/resolv.conf\netc/origin/node/node-config.yaml\netc/origin/node/flannel.etcd-client.key\netc/origin/node/flannel.etcd-client.csr\netc/origin/node/flannel.etcd-client.crt\netc/origin/node/flannel.etcd-ca.crt\netc/pki/ca-trust/source/anchors/openshift-ca.crt\netc/pki/ca-trust/source/anchors/registry-ca.crt\netc/dnsmasq.conf\netc/dnsmasq.d/origin-dns.conf\netc/dnsmasq.d/origin-upstream-dns.conf\netc/dnsmasq.d/node-dnsmasq.conf\npackages.txt\n\nIf needed, you can compress the files to save space:\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo tar -zcvf /backup/$(hostname)-$(date +%Y%m%d).tar.gz $MYBACKUPDIR\n$ sudo rm -Rf ${MYBACKUPDIR}\n\nTo create any of these files from scratch, the openshift-ansible-contrib repository contains the backup_master_node.sh script, which performs the previous steps. The script creates a directory on the host where you run the script and copies all the files previously mentioned.\n\nNOTE\nThe openshift-ansible-contrib script is not supported by Red Hat, but the reference architecture team performs testing to ensure the code operates as defined and is secure.\n\nYou can run the script on every master host with:\n\n$ mkdir ~/git\n$ cd ~/git\n$ git clone https://github.com/openshift/openshift-ansible-contrib.git\n$ cd openshift-ansible-contrib/reference-architecture/day2ops/scripts\n$ ./backup_master_node.sh -h\n\n4.2. CREATING A NODE HOST BACKUP\n\nCreating a backup of a node host is a different use case from backing up a master host. Because master hosts contain many important files, creating a backup is highly recommended. However, the nature of nodes is that anything special is replicated over the nodes in case of failover, and they typically do not contain data that is necessary to run an environment. If a backup of a node contains something necessary to run an environment, then a creating a backup is recommended.\n\nThe backup process is to be performed before any change to the infrastructure, such as a system update, upgrade, or any other significant modification. Backups should be performed on a regular basis to ensure the most recent data is available if a failure occurs.\n\nOpenShift Container Platform files\n\nNode instances run applications in the form of pods, which are based on containers. The /etc/origin/ and /etc/origin/node directories house important files, such as:\n\n- The configuration of the node services\n- Certificates generated by the installation\n- Cloud provider-related configuration\n- Keys and other authentication files, such as the dnsmasq configuration\n\nThe OpenShift Container Platform services can be customized to increase the log level, use proxies, and more, and the configuration files are stored in the /etc/sysconfig directory.\n\nProcedure\n\n1. Create a backup of the node configuration files:\n\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n2. OpenShift Container Platform uses specific files that must be taken into account when planning the backup policy, including:\n\n<table>\n<thead>\n<tr>\n<th>File</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/etc/cni/*</td>\n<td>Container Network Interface configuration (if used)</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/iptables</td>\n<td>Where the <code>iptables</code> rules are stored</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker-storage-setup</td>\n<td>The input file for <code>container-storage-setup</code> command</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker</td>\n<td>The <code>docker</code> configuration file</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker-network</td>\n<td><code>docker</code> networking configuration (i.e. MTU)</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker-storage</td>\n<td><code>docker</code> storage configuration (generated by <code>container-storage-setup</code>)</td>\n</tr>\n<tr>\n<td>/etc/dnsmasq.conf</td>\n<td>Main configuration file for <code>dnsmasq</code></td>\n</tr>\n<tr>\n<td>/etc/dnsmasq.d/*</td>\n<td>Different <code>dnsmasq</code> configuration files</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/flanneld</td>\n<td><code>flannel</code> configuration file (if used)</td>\n</tr>\n<tr>\n<td>/etc/pki/ca-trust/source/anchors/</td>\n<td>Certificates added to the system (i.e. for external registries)</td>\n</tr>\n</tbody>\n</table>\n\nTo create those files:\n\n```\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo mkdir -p ${MYBACKUPDIR}/etc/sysconfig\n$ sudo mkdir -p ${MYBACKUPDIR}/etc/pki/ca-trust/source/anchors\n$ sudo cp -aR /etc/sysconfig/{iptables,docker-*,flanneld} /etc/sysconfig/\n$ sudo cp -aR /etc/dnsmasq* /etc/cni ${MYBACKUPDIR}/etc/\n$ sudo cp -aR /etc/pki/ca-trust/source/anchors/* /etc/pki/ca-trust/source/anchors/\n```\n\n3. If a package is accidentally removed, or a file included in an `rpm` package should be restored, having a list of `rhel` packages installed on the system can be useful.\nNOTE\n\nIf using Red Hat Satellite features, such as content views or the facts store, provide a proper mechanism to reinstall the missing packages and a historical data of packages installed in the systems.\n\nTo create a list of the current rhel packages installed in the system:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo mkdir -p ${MYBACKUPDIR}\n$ rpm -qa | sort | sudo tee $MYBACKUPDIR/packages.txt\n```\n\n4. The following files should now be present in the backup directory:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo find ${MYBACKUPDIR} -mindepth 1 -type f -printf '%P\n'\netc/sysconfig/atomic-openshift-node\netc/sysconfig/flanneld\netc/sysconfig/iptables\netc/sysconfig/docker-network\netc/sysconfig/docker-storage\netc/sysconfig/docker-storage-setup\netc/sysconfig/docker-storage-setup.rpmnew\netc/origin/node/system:node:app-node-0.example.com.crt\netc/origin/node/system:node:app-node-0.example.com.key\netc/origin/node/ca.crt\netc/origin/node/system:node:app-node-0.example.com.kubeconfig\netc/origin/node/server.crt\netc/origin/node/server.key\netc/origin/node/node-dnsmasq.conf\netc/origin/node/resolv.conf\netc/origin/node/node-config.yaml\netc/origin/node/flannel.etcd-client.key\netc/origin/node/flannel.etcd-client.csr\netc/origin/node/flannel.etcd-client.crt\netc/origin/node/flannel.etcd-ca.crt\netc/origin/cloudprovider/openstack.conf\netc/pki/ca-trust/source/anchors/openshift-ca.crt\netc/pki/ca-trust/source/anchors/registry-ca.crt\ndnsmasq.conf\ndnsmasq.d/origin-dns.conf\ndnsmasq.d/origin-upstream-dns.conf\ndnsmasq.d/node-dnsmasq.conf\npackages.txt\n```\n\nIf needed, the files can be compressed to save space:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo tar -zcvf /backup/$(hostname)-$(date +%Y%m%d).tar.gz $MYBACKUPDIR\n$ sudo rm -Rf ${MYBACKUPDIR}\n```\n\nTo create any of these files from scratch, the openshift-ansible-contrib repository contains the backup_master_node.sh script, which performs the previous steps. The script creates a directory on the host running the script and copies all the files previously mentioned.\nNOTE\n\nThe openshift-ansible-contrib script is not supported by Red Hat, but the reference architecture team performs testing to ensure the code operates as defined and is secure.\n\nThe script can be executed on every master host with:\n\n```\n$ mkdir ~/git\n$ cd ~/git\n$ git clone https://github.com/openshift/openshift-ansible-contrib.git\n$ cd openshift-ansible-contrib/reference-architecture/day2ops/scripts\n$ ./backup_master_node.sh -h\n```\n\n4.3. BACKING UP REGISTRY CERTIFICATES\n\nIf you use an external secured registry, you must save all the registry certificates. The registry is secured by default.\n\nIMPORTANT\n\nYou must perform the following steps on each cluster node.\n\nProcedure\n\n1. Back up the registry certificates:\n\n```\n# cd /etc/docker/certs.d/\n# tar cf /tmp/docker-registry-certs-$(hostname).tar *\n```\n\n2. Move the backup to an external location.\n\nNOTE\n\nWhen working with one or more external secured registry, any host that pulls or pushes images must trust the registry certificates to run pods.\n\n4.4. BACKING UP OTHER INSTALLATION FILES\n\nBack up the files that you used to install OpenShift Container Platform.\n\nProcedure\n\n1. Because the restoration procedure involves a complete reinstallation, save all the files used in the initial installation. These files might include:\n - Ansible playbooks and inventory files from the cluster installation\n - `/etc/yum.repos.d/ose.repo` from the disconnected installation method\n\n2. Backup the procedures for post-installation steps. Some installations might involve steps that are not included in the installer. These steps might include changes to the services outside of the control of OpenShift Container Platform or the installation of extra services like monitoring\nagents. Additional configuration that is not yet supported by the advanced installer might also be affected, such as using multiple authentication providers.\n\n4.5. BACKING UP APPLICATION DATA\n\nIn many cases, you can back up application data by using the `oc rsync` command, assuming `rsync` is installed within the container image. The Red Hat `rhel7` base image contains `rsync`. Therefore, all images that are based on `rhel7` contain it as well. See Troubleshooting and Debugging CLI Operations - `rsync`.\n\n**WARNING**\n\nThis is a *generic* backup of application data and does not take into account application-specific backup procedures, for example, special export and import procedures for database systems.\n\nOther means of backup might exist depending on the type of the persistent volume you use, for example, Cinder, NFS, or Gluster.\n\nThe paths to back up are also *application specific*. You can determine what path to back up by looking at the `mountPath` for volumes in the `deploymentconfig`.\n\n**NOTE**\n\nYou can perform this type of application data backup only while the application pod is running.\n\n**Procedure**\n\n**Example of backing up a Jenkins deployment’s application data**\n\n1. Get the application data `mountPath` from the `deploymentconfig`:\n\n ```bash\n $ oc get dc/jenkins -o jsonpath='{ .spec.template.spec.containers[?(@.name==\"jenkins\")].volumeMounts[?(@.name==\"jenkins-data\")].mountPath }' /var/lib/jenkins\n ```\n\n2. Get the name of the pod that is currently running:\n\n ```bash\n $ oc get pod --selector=deploymentconfig=jenkins -o jsonpath='{ .metadata.name }' jenkins-1-37nux\n ```\n\n3. Use the `oc rsync` command to copy application data:\n\n ```bash\n $ oc rsync jenkins-1-37nux:/var/lib/jenkins /tmp/\n ```\n\n4.6. ETCD BACKUP\netcd is the key value store for all object definitions, as well as the persistent master state. Other components watch for changes, then bring themselves into the desired state.\n\nOpenShift Container Platform versions prior to 3.5 use etcd version 2 (v2), while 3.5 and later use version 3 (v3). The data model between the two versions of etcd is different. etcd v3 can use both the v2 and v3 data models, whereas etcd v2 can only use the v2 data model. In an etcd v3 server, the v2 and v3 data stores exist in parallel and are independent.\n\nFor both v2 and v3 operations, you can use the `ETCDCTL_API` environment variable to use the proper API:\n\n```\n$ etcdctl -v\netcdctl version: 3.2.5\nAPI version: 2\n$ ETCDCTL_API=3 etcdctl version\netcdctl version: 3.2.5\nAPI version: 3.2\n```\n\nSee Migrating etcd Data (v2 to v3) section in the OpenShift Container Platform 3.7 documentation for information about how to migrate to v3.\n\nThe etcd backup process is composed of two different procedures:\n\n- **Configuration backup**: Including the required etcd configuration and certificates\n- **Data backup**: Including both v2 and v3 data model.\n\nYou can perform the data backup process on any host that has connectivity to the etcd cluster, where the proper certificates are provided, and where the `etcdctl` tool is installed.\n\n**NOTE**\n\nThe backup files must be copied to an external system, ideally outside the OpenShift Container Platform environment, and then encrypted.\n\nNote that the etcd backup still has all the references to current storage volumes. When you restore etcd, OpenShift Container Platform starts launching the previous pods on nodes and reattaching the same storage. This process is no different than the process of when you remove a node from the cluster and add a new one back in its place. Anything attached to that node is reattached to the pods on whatever nodes they are rescheduled to.\n\n### 4.6.1. Backing up etcd\n\nWhen you back up etcd, you must back up both the etcd configuration files and the etcd data.\n\n#### 4.6.1.1. Backing up etcd configuration files\n\nThe etcd configuration files to be preserved are all stored in the `/etc/etcd` directory of the instances where etcd is running. This includes the etcd configuration file (`/etc/etcd/etcd.conf`) and the required certificates for cluster communication. All those files are generated at installation time by the Ansible installer.\n\n**Procedure**\n\nFor each etcd member of the cluster, back up the etcd configuration.\n4.6.1.2. Backing up etcd data\n\nPrerequisites\n\nNOTE\n\nThe certificates and configuration files on each etcd cluster member are unique.\n\nBefore backing up etcd:\n\n- **etcdctl** binaries should be available or, in containerized installations, the **rhel7/etcd** container should be available.\n\n- Ensure connectivity with the etcd cluster (port 2379/tcp)\n\n- Ensure the proper certificates to connect to the etcd cluster\n\n1. To ensure the etcd cluster is working, check its health.\n\n - If you use the etcd v2 API, run the following command:\n\n ```\n # etcdctl --cert-file=/etc/etcd/peer.crt \\\n --key-file=/etc/etcd/peer.key \\\n --ca-file=/etc/etcd/ca.crt \\\n --peers=\"https://*master-0.example.com*:2379,\" \\\n https://*master-1.example.com*:2379,\\n https://*master-2.example.com*:2379\" \\\n cluster-health\n member 5ee217d19001 is healthy: got healthy result from https://192.168.55.12:2379\n member 2a529ba1840722c0 is healthy: got healthy result from https://192.168.55.8:2379\n member ed40ef277d7599 is healthy: got healthy result from https://192.168.55.13:2379\n cluster is healthy\n ```\n\n - If you use the etcd v3 API, run the following command:\n\n ```\n # ETCDCTL_API=3 etcdctl --cert=\"/etc/etcd/peer.crt\" \\\n --key=\"/etc/etcd/peer.key\" \\\n --cacert=\"/etc/etcd/ca.crt\" \\\n --endpoints=\"https://*master-0.example.com*:2379,\" \\\n https://*master-1.example.com*:2379,\\n https://*master-2.example.com*:2379\"\n ```\nhttps://master-2.example.com:*2379*\n\nendpoint health\n\nhttps://master-0.example.com:2379 is healthy: successfully committed proposal: took = 5.011358ms\nhttps://master-1.example.com:2379 is healthy: successfully committed proposal: took = 1.305173ms\nhttps://master-2.example.com:2379 is healthy: successfully committed proposal: took = 1.388772ms\n\n2. Check the member list.\n\n- If you use the etcd v2 API, run the following command:\n\n```\n# etcdctl2 member list\n2a371dd20f21ca8d: name=master-1.example.com\nisLeader=false\n40bef16c79b3163: name=master-0.example.com\npeerURLs=https://192.168.55.8:2380 clientURLs=https://192.168.55.8:2379\nisLeader=false\n95dc17ffce8ee29: name=master-2.example.com\nisLeader=true\n```\n\n- If you use the etcd v3 API, run the following command:\n\n```\n# etcdctl3 member list\n40bef16c79b3163, started, master-0.example.com, https://192.168.55.8:2380, https://192.168.55.8:2379\n```\n\nProcedure\n\n**NOTE**\n\nWhile the `etcdctl backup` command is used to perform the backup, etcd v3 has no concept of a *backup*. Instead, you either take a *snapshot* from a live member with the `etcdctl snapshot save` command or copy the *member/snap/db* file from an etcd data directory.\n\nThe `etcdctl backup` command rewrites some of the metadata contained in the backup, specifically, the node ID and cluster ID, which means that in the backup, the node loses its former identity. To recreate a cluster from the backup, you create a new, single-node cluster, then add the rest of the nodes to the cluster. The metadata is rewritten to prevent the new node from joining an existing cluster.\n\nBack up the etcd data:\n\n- If you use the v2 API, take the following actions:\n \n a. Stop all etcd services:\n# systemctl stop etcd.service\n\nb. Create the etcd data backup and copy the etcd db file:\n\n```\n# mkdir -p /backup/etcd-$(date +%Y%m%d)\n# etcdctl2 backup \\\n --data-dir /var/lib/etcd \\\n --backup-dir /backup/etcd-$(date +%Y%m%d)\n# cp /var/lib/etcd/member/snap/db /backup/etcd-$(date +%Y%m%d)\n```\n\nc. Start all etcd services:\n\n```\n# systemctl start etcd.service\n```\n\n- If you use the v3 API, run the following commands:\n\n**IMPORTANT**\nBecause clusters upgraded from previous versions of OpenShift Container Platform might contain v2 data stores, back up both v2 and v3 datastores.\n\na. Back up etcd v3 data:\n\n```\n# systemctl show etcd --property=ActiveState,SubState\n# mkdir -p /backup/etcd-$(date +%Y%m%d)\n# etcdctl3 snapshot save */backup/etcd-$(date +%Y%m%d)*/db\n```\n\n```\nSnapshot saved at /backup/etcd-<date>/db\n```\n\nb. Back up etcd v2 data:\n\n```\n# systemctl stop etcd.service\n# etcdctl2 backup \\\n --data-dir /var/lib/etcd \\\n --backup-dir /backup/etcd-$(date +%Y%m%d)\n# cp /var/lib/etcd/member/snap/db /backup/etcd-$(date +%Y%m%d)\n# systemctl start etcd.service\n```\n\n**NOTE**\nThe `etcdctl snapshot save` command requires the etcd service to be running.\n\nIn these commands, a `/backup/etcd-<date>/` directory is created, where `<date>` represents the current date, which must be an external NFS share, S3 bucket, or any external storage location.\n\nIn the case of an all-in-one cluster, the etcd data directory is located in the `/var/lib/origin/openshift.local.etcd` directory.\n\n### 4.7. BACKING UP A PROJECT\nCreating a backup of all relevant data involves exporting all important information, then restoring into a new project.\n\n**NOTE**\n\nCurrently, a OpenShift Container Platform project back up and restore tool is being developed by Red Hat. See the following bug for more information:\n\n- [bugzilla 1303205](https://bugzilla.redhat.com/show_bug.cgi?id=1303205).\n\n**Procedure**\n\n1. List all the relevant data to back up:\n\n ```\n $ oc get all\n NAME TYPE FROM LATEST\n bc/ruby-ex Source Git 1\n \n NAME TYPE FROM STATUS STARTED DURATION\n builds/ruby-ex-1 Source Git@c457001 Complete 2 minutes ago 35s\n \n NAME DOCKER REPO TAGS UPDATED\n is/guestbook 10.111.255.221:5000/myproject/guestbook latest 2 minutes ago\n is/hello-openshift 10.111.255.221:5000/myproject/hello-openshift latest 2 minutes ago\n is/ruby-22-centos7 10.111.255.221:5000/myproject/ruby-22-centos7 latest 2 minutes ago\n is/ruby-ex 10.111.255.221:5000/myproject/ruby-ex latest 2 minutes ago\n \n NAME REVISION DESIRED CURRENT TRIGGERED BY\n dc/guestbook 1 1 1 config,image(guestbook:latest)\n dc/hello-openshift 1 1 1 config,image(hello-openshift:latest)\n dc/ruby-ex 1 1 1 config,image(ruby-ex:latest)\n \n NAME DESIRED CURRENT READY AGE\n rc/guestbook-1 1 1 1 2m\n rc/hello-openshift-1 1 1 1 2m\n rc/ruby-ex-1 1 1 1 2m\n \n NAME READY STATUS RESTARTS AGE\n po/guestbook-1-c010g 1/1 Running 0 2m\n po/hello-openshift-1-4zw2q 1/1 Running 0 2m\n po/ruby-ex-1-build 0/1 Completed 0 2m\n po/ruby-ex-1-rxc74 1/1 Running 0 2m\n \n NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE\n svc/guestbook 10.111.105.84 <none> 3000/TCP 2m\n svc/hello-openshift 10.111.230.24 <none> 8080/TCP,8888/TCP 2m\n svc/ruby-ex 10.111.232.117 <none> 8080/TCP 2m\n ```\n\n2. Export the project objects to a `.yaml` or `.json` file.\n\n - To export the project objects into a `project.yaml` file:\n ```\n $ oc export all -o yaml > project.yaml\n ```\n - To export the project objects into a `project.json` file:\n3. Export the project’s role bindings, secrets, service accounts, and persistent volume claims:\n\n```bash\n$ for object in rolebindings serviceaccounts secrets imagestreamtags podpreset cms egressnetworkpolicies rolebindingrestrictions limitranges resourcequotas pvcs templates cronjobs statefulsets hpas deployments replicaset endpoints do\n oc export $object -o yaml > $object.yaml\ndone\n```\n\n4. To list all the namespaced objects:\n\n```bash\n$ oc api-resources --namespaced=true -o name\n```\n\n5. Some exported objects can rely on specific metadata or references to unique IDs in the project. This is a limitation on the usability of the recreated objects. When using `imagestreams`, the image parameter of a `deploymentconfig` can point to a specific sha checksum of an image in the internal registry that would not exist in a restored environment. For instance, running the sample \"ruby-ex\" as `oc new-app centos/ruby-22-centos7~https://github.com/sclorg/ruby-ex.git` creates an `imagestream` `ruby-ex` using the internal registry to host the image:\n\n```bash\n$ oc get dc ruby-ex -o jsonpath=\"{.spec.template.spec.containers[].image}\"\n10.111.255.221:5000/myproject/ruby-ex@sha256:880c720b23c8d15a53b01db52f7abdcbb2280e03f686a5c8eddef1a2a7b21cee\n```\n\nIf importing the `deploymentconfig` as it is exported with `oc export` it fails if the image does not exist.\n\n### 4.8. BACKING UP PERSISTENT VOLUME CLAIMS\n\nYou can synchronize persistent data from inside of a container to a server.\n\n**IMPORTANT**\n\nDepending on the provider that is hosting the OpenShift Container Platform environment, the ability to launch third party snapshot services for backup and restore purposes also exists. As OpenShift Container Platform does not have the ability to launch these services, this guide does not describe these steps.\n\nConsult any product documentation for the correct backup procedures of specific applications. For example, copying the mysql data directory itself does not create a usable backup. Instead, run the specific backup procedures of the associated application and then synchronize any data. This includes using snapshot solutions provided by the OpenShift Container Platform hosting platform.\n\n**Procedure**\n\n1. View the project and pods:\n\n```bash\n$ oc get pods\nNAME READY STATUS RESTARTS AGE\ndemo-1-build 0/1 Completed 0 2h\n```\nDescribe the desired pod to find the volumes that are currently used by a persistent volume:\n\n```sh\n$ oc describe pod demo-2-fxx6d\nName: demo-2-fxx6d\nNamespace: test\nSecurity Policy: restricted\nNode: ip-10-20-6-20.ec2.internal/10.20.6.20\nStart Time: Tue, 05 Dec 2017 12:54:34 -0500\nLabels: app=demo\ndeployment=demo-2\ndeploymentconfig=demo\nStatus: Running\nIP: 172.16.12.5\nControllers: ReplicationController/demo-2\nContainers:\n demo:\n Container ID: docker://201f3e55b373641eb36945d723e1e212ecab847311109b5cee1fd0109424217a\n Image: docker-registry.default.svc:5000/test/demo@sha256:0a9f2487a0d95d51511e49d20dc9ff6f350436f935968b0c83fcb98a7a8c381a\n Image ID: docker-pullable://docker-registry.default.svc:5000/test/demo@sha256:0a9f2487a0d95d51511e49d20dc9ff6f350436f935968b0c83fcb98a7a8c381a\n Port: 8080/TCP\n State: Running\n Started: Tue, 05 Dec 2017 12:54:52 -0500\n Ready: True\n Restart Count: 0\n Volume Mounts:\n */opt/app-root/src/uploaded from persistent-volume (rw)*\n /var/run/secrets/kubernetes.io/serviceaccount from default-token-8mmrk (ro)\n Environment Variables: <none>\n```\n\nThis output shows that the persistent data is in the `*/opt/app-root/src/uploaded` directory.\n\nCopy the data locally:\n\n```sh\n$ oc rsync demo-2-fxx6d:/opt/app-root/src/uploaded ./demo-app\nreceiving incremental file list\nuploaded/\nuploaded/ocp_sop.txt\nuploaded/lost+found/\n\nsent 38 bytes received 190 bytes 152.00 bytes/sec\ntotal size is 32 speedup is 0.14\n```\n\nThe `ocp_sop.txt` file is downloaded to the local system to be backed up by backup software or another backup mechanism.\nNOTE\n\nYou can also use the previous steps if a pod starts without needing to use a **pvc**, but you later decide that a **pvc** is necessary. You can preserve the data and then use the restorat process to populate the new storage.\nCHAPTER 5. HOST-LEVEL TASKS\n\n5.1. ADDING A HOST TO THE CLUSTER\n\nFor information on adding master or node hosts to a cluster, see the Adding hosts to an existing cluster section in the Install and configuration guide.\n\n5.2. MASTER HOST TASKS\n\n5.2.1. Deprecating a master host\n\nDeprecating a master host removes it from the OpenShift Container Platform environment.\n\nThe reasons to deprecate or scale down master hosts include hardware re-sizing or replacing the underlying infrastructure.\n\nHighly available OpenShift Container Platform environments require at least three master hosts and three etcd nodes. Usually, the master hosts are colocated with the etcd services. If you deprecate a master host, you must also deprecate the etcd service on that host.\n\nIMPORTANT\n\nEnsure that the master and etcd services are always deployed in odd numbers due to the voting mechanisms that take place among those services.\n\n5.2.1.1. Creating a master host backup\n\nPerform this backup process before any change to the OpenShift Container Platform infrastructure, such as a system update, upgrade, or any other significant modification. Back up data regularly to ensure that recent data is available if a failure occurs.\n\nOpenShift Container Platform files\n\nThe master instances run important services, such as the API, controllers. The /etc/origin/master directory stores many important files:\n\n- The configuration, the API, controllers, services, and more\n- Certificates generated by the installation\n- All cloud provider-related configuration\n- Keys and other authentication files, such as htpasswd if you use htpasswd\n- And more\n\nYou can customize OpenShift Container Platform services, such as increasing the log level or using proxies. The configuration files are stored in the /etc/sysconfig directory.\n\nBecause the masters are also nodes, back up the entire /etc/origin directory.\n\nProcedure\nIMPORTANT\n\nYou must perform the following steps on each master node.\n\n1. Create a backup of the master host configuration files:\n\n ```\n $ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n $ sudo mkdir -p ${MYBACKUPDIR}/etc/sysconfig\n $ sudo cp -aR /etc/origin ${MYBACKUPDIR}/etc\n $ sudo cp -aR /etc/sysconfig/atomic-* ${MYBACKUPDIR}/etc/sysconfig/\n ```\n\nNOTE\n\nThe configuration file is stored in the `/etc/sysconfig/atomic-openshift-master-api`, and `/etc/sysconfig/atomic-openshift-master-controllers` directories.\n\nWARNING\n\nThe `/etc/origin/master/ca.serial.txt` file is generated on only the first master listed in the Ansible host inventory. If you deprecate the first master host, copy the `/etc/origin/master/ca.serial.txt` file to the rest of master hosts before the process.\n\n2. Other important files that need to be considered when planning a backup include:\n\n<table>\n<thead>\n<tr>\n<th>File</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>/etc/cni/*</code></td>\n<td>Container Network Interface configuration (if used)</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/iptables</code></td>\n<td>Where the <code>iptables</code> rules are stored</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/docker-storage-setup</code></td>\n<td>The input file for <code>container-storage-setup</code> command</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/docker</code></td>\n<td>The <code>docker</code> configuration file</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/docker-network</code></td>\n<td><code>docker</code> networking configuration (i.e. MTU)</td>\n</tr>\n<tr>\n<td><code>/etc/sysconfig/docker-storage</code></td>\n<td><code>docker</code> storage configuration (generated by <code>container-storage-setup</code>)</td>\n</tr>\n<tr>\n<td><code>/etc/dnsmasq.conf</code></td>\n<td>Main configuration file for <code>dnsmasq</code></td>\n</tr>\n<tr>\n<td><code>/etc/dnsmasq.d/*</code></td>\n<td>Different <code>dnsmasq</code> configuration files</td>\n</tr>\n</tbody>\n</table>\nCreate a backup of those files:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo mkdir -p ${MYBACKUPDIR}/etc/sysconfig\n$ sudo mkdir -p ${MYBACKUPDIR}/etc/pki/ca-trust/source/anchors\n$ sudo cp -aR /etc/sysconfig/{iptables,docker-*,flanneld} \\\n ${MYBACKUPDIR}/etc/sysconfig/\n$ sudo cp -aR /etc/dnsmasq* /etc/cni ${MYBACKUPDIR}/etc/\n$ sudo cp -aR /etc/pki/ca-trust/source/anchors/* \\\n ${MYBACKUPDIR}/etc/pki/ca-trust/source/anchors/\n```\n\n3. If a package is accidentally removed or you need to restore a file that is included in an *rpm* package, having a list of *rhel* packages installed on the system can be useful.\n\n**NOTE**\n\nIf you use Red Hat Satellite features, such as content views or the facts store, provide a proper mechanism to reinstall the missing packages and a historical data of packages installed in the systems.\n\nTo create a list of the current *rhel* packages installed in the system:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo mkdir -p $MYBACKUPDIR\n$ rpm -qa | sort | sudo tee $MYBACKUPDIR/packages.txt\n```\n\n4. If you used the previous steps, the following files are present in the backup directory:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo find $MYBACKUPDIR -mindepth 1 -type f -printf '%P\n' \n etc/sysconfig/atomic-openshift-master \n etc/sysconfig/atomic-openshift-master-api \n etc/sysconfig/atomic-openshift-master-controllers \n etc/sysconfig/atomic-openshift-node \n etc/sysconfig/flanneld \n etc/sysconfig/iptables \n etc/sysconfig/docker-network \n etc/sysconfig/docker-storage \n etc/sysconfig/docker-storage-setup \n etc/sysconfig/docker-storage-setup.rpmnew \n etc/origin/master/ca.crt \n etc/origin/master/ca.key \n etc/origin/master/ca.serial.txt \n etc/origin/master/ca-bundle.crt \n etc/origin/master/master.proxy-client.crt \n etc/origin/master/master.proxy-client.key \n etc/origin/master/service-signer.crt\n```\netc/origin/master/service-signer.key\netc/origin/master/serviceaccounts.private.key\netc/origin/master/serviceaccounts.public.key\netc/origin/master/openshift-master.crt\netc/origin/master/openshift-master.key\netc/origin/master/openshift-master.kubeconfig\netc/origin/master/master.server.crt\netc/origin/master/master.server.key\netc/origin/master/master.kubelet-client.crt\netc/origin/master/master.kubelet-client.key\netc/origin/master/admin.crt\netc/origin/master/admin.key\netc/origin/master/master.kubeconfig\netc/origin/master/etcd.server.crt\netc/origin/master/etcd.server.key\netc/origin/master/master.etcd-client.key\netc/origin/master/master.etcd-client.csr\netc/origin/master/master.etcd-client.crt\netc/origin/master/master.etcd-ca.crt\netc/origin/master/policy.json\netc/origin/master/scheduler.json\netc/origin/master/htpasswd\netc/origin/master/session-secrets.yaml\netc/origin/master/openshift-router.crt\netc/origin/master/openshift-router.key\netc/origin/master/registry.crt\netc/origin/master/registry.key\netc/origin/master/master-config.yaml\netc/origin/generated-configs/master-master-1.example.com/master.server.crt\netc/origin/cloudprovider/openstack.conf\netc/origin/node/system:node:master-0.example.com.crt\netc/origin/node/system:node:master-0.example.com.key\netc/origin/node/ca.crt\netc/origin/node/system:node:master-0.example.com.kubeconfig\netc/origin/node/server.crt\netc/origin/node/server.key\netc/origin/node/node-dnsmasq.conf\netc/origin/node/resolv.conf\netc/origin/node/node-config.yaml\netc/origin/node/flannel.etcd-client.key\netc/origin/node/flannel.etcd-client.csr\netc/origin/node/flannel.etcd-client.crt\netc/origin/node/flannel.etcd-ca.crt\netc/pki/ca-trust/source/anchors/openshift-ca.crt\netc/pki/ca-trust/source/anchors/registry-ca.crt\ndnsmasq.conf\ndnsmasq.d/origin-dns.conf\ndnsmasq.d/origin-upstream-dns.conf\ndnsmasq.d/node-dnsmasq.conf\npackages.txt\n\nIf needed, you can compress the files to save space:\nTo create any of these files from scratch, the openshift-ansible-contrib repository contains the backup_master_node.sh script, which performs the previous steps. The script creates a directory on the host where you run the script and copies all the files previously mentioned.\n\n```\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo tar -zcvf /backup/$(hostname)-$(date +%Y%m%d).tar.gz $MYBACKUPDIR\n$ sudo rm -Rf ${MYBACKUPDIR}\n```\n\nYou can run the script on every master host with:\n\n```\n$ mkdir ~/git\n$ cd ~/git\n$ git clone https://github.com/openshift/openshift-ansible-contrib.git\n$ cd openshift-ansible-contrib/reference-architecture/day2ops/scripts\n$ ./backup_master_node.sh -h\n```\n\n5.2.1.2. Backing up etcd\n\nWhen you back up etcd, you must back up both the etcd configuration files and the etcd data.\n\n5.2.1.2.1. Backing up etcd configuration files\n\nThe etcd configuration files to be preserved are all stored in the /etc/etcd directory of the instances where etcd is running. This includes the etcd configuration file (/etc/etcd/etcd.conf) and the required certificates for cluster communication. All those files are generated at installation time by the Ansible installer.\n\n**Procedure**\n\nFor each etcd member of the cluster, back up the etcd configuration.\n\n```\n$ ssh master-0\n # mkdir -p /backup/etcd-config-$(date +%Y%m%d)/\n # cp -R /etc/etcd/ /backup/etcd-config-$(date +%Y%m%d)/\n```\n\n**NOTE**\n\nThe certificates and configuration files on each etcd cluster member are unique.\n\n5.2.1.2.2. Backing up etcd data\n\n**Prerequisites**\nNOTE\n\nThe OpenShift Container Platform installer creates aliases to avoid typing all the flags named `etcdctl2` for etcd v2 tasks and `etcdctl3` for etcd v3 tasks.\n\nHowever, the `etcdctl3` alias does not provide the full endpoint list to the `etcdctl` command, so the `--endpoints` option with all the endpoints must be provided.\n\nBefore backing up etcd:\n\n- `etcdctl` binaries should be available or, in containerized installations, the `rhel7/etcd` container should be available\n- Ensure connectivity with the etcd cluster (port 2379/tcp)\n- Ensure the proper certificates to connect to the etcd cluster\n\nProcedure\n\nNOTE\n\nWhile the `etcdctl backup` command is used to perform the backup, etcd v3 has no concept of a backup. Instead, you either take a snapshot from a live member with the `etcdctl snapshot save` command or copy the `member/snap/db` file from an etcd data directory.\n\nThe `etcdctl backup` command rewrites some of the metadata contained in the backup, specifically, the node ID and cluster ID, which means that in the backup, the node loses its former identity. To recreate a cluster from the backup, you create a new, single-node cluster, then add the rest of the nodes to the cluster. The metadata is rewritten to prevent the new node from joining an existing cluster.\n\nBack up the etcd data:\n\n- If you use the v2 API, take the following actions:\n \n a. Stop all etcd services:\n\n ```\n # systemctl stop etcd.service\n ```\n\n b. Create the etcd data backup and copy the etcd `db` file:\n\n ```\n # mkdir -p /backup/etcd-$(date +%Y%m%d)\n # etcdctl2 backup \\\n --data-dir /var/lib/etcd \\\n --backup-dir /backup/etcd-$(date +%Y%m%d)\n # cp /var/lib/etcd/member/snap/db /backup/etcd-$(date +%Y%m%d)\n ```\n\n c. Start all etcd services:\n\n ```\n # systemctl start etcd.service\n ```\n\n- If you use the v3 API, run the following commands:\nIMPORTANT\n\nBecause clusters upgraded from previous versions of OpenShift Container Platform might contain v2 data stores, back up both v2 and v3 datastores.\n\na. Back up etcd v3 data:\n\n# systemctl show etcd --property=ActiveState,SubState\n# mkdir -p /backup/etcd-$(date +%Y%m%d)\n# etcdctl3 snapshot save */backup/etcd-$(date +%Y%m%d)*/db\nSnapshot saved at /backup/etcd-<date>/db\n\nb. Back up etcd v2 data:\n\n# systemctl stop etcd.service\n# etcdctl2 backup \\n --data-dir /var/lib/etcd \\n --backup-dir /backup/etcd-$(date +%Y%m%d) \\n# cp /var/lib/etcd/member/snap/db /backup/etcd-$(date +%Y%m%d) \\n# systemctl start etcd.service\n\nNOTE\n\nThe etcdctl snapshot save command requires the etcd service to be running.\n\nIn these commands, a /backup/etcd-<date>/ directory is created, where <date> represents the current date, which must be an external NFS share, S3 bucket, or any external storage location.\n\nIn the case of an all-in-one cluster, the etcd data directory is located in the /var/lib/origin/openshift.local.etcd directory.\n\n5.2.1.3. Deprecating a master host\n\nMaster hosts run important services, such as the OpenShift Container Platform API and controllers services. In order to deprecate a master host, these services must be stopped.\n\nThe OpenShift Container Platform API service is an active/active service, so stopping the service does not affect the environment as long as the requests are sent to a separate master server. However, the OpenShift Container Platform controllers service is an active/passive service, where the services leverage etcd to decide the active master.\n\nDeprecating a master host in a multi-master architecture includes removing the master from the load balancer pool to avoid new connections attempting to use that master. This process depends heavily on the load balancer used. The steps below show the details of removing the master from haproxy. In the event that OpenShift Container Platform is running on a cloud provider, or using a F5 appliance, see the specific product documents to remove the master from rotation.\n\nProcedure\n\n1. Remove the backend section in the /etc/haproxy/haproxy.cfg configuration file. For example, if deprecating a master named master-0.example.com using haproxy, ensure the host name is removed from the following:\n\n-\n2. Then, restart the **haproxy** service.\n\n ```\n $ sudo systemctl restart haproxy\n ```\n\n3. Once the master is removed from the load balancer, disable the API and controller services:\n\n ```\n $ sudo systemctl disable --now atomic-openshift-master-api\n $ sudo systemctl disable --now atomic-openshift-master-controllers\n ```\n\n4. Because the master host is a schedulable OpenShift Container Platform node, follow the steps in the **Deprecating a node host** section.\n\n5. Remove the master host from the **[masters]** and **[nodes]** groups in the `/etc/ansible/hosts` Ansible inventory file to avoid issues if running any Ansible tasks using that inventory file.\n\n **WARNING**\n\n Deprecating the first master host listed in the Ansible inventory file requires extra precautions.\n\n The `/etc/origin/master/ca.serial.txt` file is generated on only the first master listed in the Ansible host inventory. If you deprecate the first master host, copy the `/etc/origin/master/ca.serial.txt` file to the rest of master hosts before the process.\n\n6. The **kubernetes** service includes the master host IPs as endpoints. To verify that the master has been properly deprecated, review the **kubernetes** service output and see if the deprecated master has been removed:\n\n ```\n $ oc describe svc kubernetes -n default\n Name: kubernetes\n Namespace: default\n Labels: component=apiserver\n provider=kubernetes\n Annotations: <none>\n Selector: <none>\n Type: ClusterIP\n IP: 10.111.0.1\n Port: https 443/TCP\n Port: dns 53/UDP\n ```\nPort: dns-tcp 53/TCP\nSession Affinity: ClientIP\nEvents: <none>\n\nAfter the master has been successfully deprecated, the host where the master was previously running can be safely deleted.\n\n5.2.1.4. Removing an etcd host\n\nIf an etcd host fails beyond restoration, remove it from the cluster.\n\nSteps to be performed on all masters hosts\n\nProcedure\n\n1. Remove each other etcd host from the etcd cluster. Run the following command for each etcd node:\n\n ```bash\n # etcdctl -C https://<surviving host IP address>:2379 \\\n --ca-file=/etc/etcd/ca.crt \\\n --cert-file=/etc/etcd/peer.crt \\\n --key-file=/etc/etcd/peer.key member remove <failed member ID>\n ```\n\n2. Restart the master API service on every master:\n\n ```bash\n # systemctl restart atomic-openshift-master-api\n ```\n Or, if using a single master cluster installation:\n\n ```bash\n # systemctl restart atomic-openshift-master\n ```\n\nSteps to be performed in the current etcd cluster\n\nProcedure\n\n1. Remove the failed host from the cluster:\n\n ```bash\n # etcdctl cluster-health\n member 5ee217d19001 is healthy: got healthy result from https://192.168.55.12:2379\n member 2a529ba1840722c0 is healthy: got healthy result from https://192.168.55.8:2379\n member 8372784203e11288 is unreachable: [https://192.168.55.21:2379] are all unreachable\n member ed4f0efd277d7599 is healthy: got healthy result from https://192.168.55.13:2379\n cluster is healthy\n # etcdctl member remove 8372784203e11288\n Removed member 8372784203e11288 from cluster\n ```\n\n2. Check the health of the remaining members:\n\n ```bash\n # etcdctl cluster-health\n member 5ee217d19001 is healthy: got healthy result from https://192.168.55.12:2379\n ```\nmember 2a529ba1840722c0 is healthy: got healthy result from https://192.168.55.8:2379\nmember ed4f0efd277d7599 is healthy: got healthy result from https://192.168.55.13:2379\ncluster is healthy\n\n1. The `remove` command requires the etcd ID, not the hostname.\n\n2. To ensure the etcd configuration does not use the failed host when the etcd service is restarted, modify the `/etc/etcd/etcd.conf` file on all remaining etcd hosts and remove the failed host in the value for the `ETCD_INITIAL_CLUSTER` variable:\n\n ```bash\n # vi /etc/etcd/etcd.conf\n \n For example:\n \n \n becomes:\n \n `ETCD_INITIAL_CLUSTER=master-0.example.com=https://192.168.55.8:2380,master-1.example.com=https://192.168.55.12:2380`\n \n **NOTE**\n \n Restarting the etcd services is not required, because the failed host is removed using `etcdctl`.\n\n3. Modify the Ansible inventory file to reflect the current status of the cluster and to avoid issues when re-running a playbook:\n\n ```\n [OSEv3:children]\n masters\n nodes\n etcd\n\n … [OUTPUT ABBREVIATED] …\n \n [etcd]\n master-0.example.com\n master-1.example.com\n \n 4. If you are using Flannel, modify the `flanneld` service configuration located at `/etc/sysconfig/flanneld` on every host and remove the etcd host:\n\n ```bash\n \n 5. Restart the `flanneld` service:\n\n ```bash\n # systemctl restart flanneld.service\n ```\n5.2.2. Creating a master host backup\n\nPerform this backup process before any change to the OpenShift Container Platform infrastructure, such as a system update, upgrade, or any other significant modification. Back up data regularly to ensure that recent data is available if a failure occurs.\n\nOpenShift Container Platform files\n\nThe master instances run important services, such as the API, controllers. The `/etc/origin/master` directory stores many important files:\n\n- The configuration, the API, controllers, services, and more\n- Certificates generated by the installation\n- All cloud provider-related configuration\n- Keys and other authentication files, such as `htpasswd` if you use htpasswd\n- And more\n\nYou can customize OpenShift Container Platform services, such as increasing the log level or using proxies. The configuration files are stored in the `/etc/sysconfig` directory.\n\nBecause the masters are also nodes, back up the entire `/etc/origin` directory.\n\nProcedure\n\n**IMPORTANT**\n\nYou must perform the following steps on each master node.\n\n1. Create a backup of the master host configuration files:\n\n ```bash\n $ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n $ sudo mkdir -p ${MYBACKUPDIR}/etc/sysconfig\n $ sudo cp -aR /etc/origin ${MYBACKUPDIR}/etc\n $ sudo cp -aR /etc/sysconfig/atomic-* ${MYBACKUPDIR}/etc/sysconfig/\n ``\n\n**NOTE**\n\nThe configuration file is stored in the `/etc/sysconfig/atomic-openshift-master-api`, and `/etc/sysconfig/atomic-openshift-master-controllers` directories.\n\n**WARNING**\n\nThe `/etc/origin/master/ca.serial.txt` file is generated on only the first master listed in the Ansible host inventory. If you deprecate the first master host, copy the `/etc/origin/master/ca.serial.txt` file to the rest of master hosts before the process.\n2. Other important files that need to be considered when planning a backup include:\n\n<table>\n<thead>\n<tr>\n<th>File</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/etc/cni/*</td>\n<td>Container Network Interface configuration (if used)</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/iptables</td>\n<td>Where the <strong>iptables</strong> rules are stored</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker-storage-setup</td>\n<td>The input file for <strong>container-storage-setup</strong> command</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker</td>\n<td>The <strong>docker</strong> configuration file</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker-network</td>\n<td><strong>docker</strong> networking configuration (i.e. MTU)</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker-storage</td>\n<td><strong>docker</strong> storage configuration (generated by <strong>container-storage-setup</strong>)</td>\n</tr>\n<tr>\n<td>/etc/dnsmasq.conf</td>\n<td>Main configuration file for <strong>dnsmasq</strong></td>\n</tr>\n<tr>\n<td>/etc/dnsmasq.d/*</td>\n<td>Different <strong>dnsmasq</strong> configuration files</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/flanneld</td>\n<td><strong>flannel</strong> configuration file (if used)</td>\n</tr>\n<tr>\n<td>/etc/pki/ca-trust/source/anchors/*</td>\n<td>Certificates added to the system (i.e. for external registries)</td>\n</tr>\n</tbody>\n</table>\n\nCreate a backup of those files:\n\n```\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo mkdir -p ${MYBACKUPDIR}/etc/sysconfig\n$ sudo mkdir -p ${MYBACKUPDIR}/etc/pki/ca-trust/source/anchors\n$ sudo cp -aR /etc/sysconfig/{iptables,docker-*,flanneld} \\\\ ${MYBACKUPDIR}/etc/sysconfig/\n$ sudo cp -aR /etc/dnsmasq* /etc/cni ${MYBACKUPDIR}/etc/\n$ sudo cp -aR /etc/pki/ca-trust/source/anchors/* \\\\ ${MYBACKUPDIR}/etc/pki/ca-trust/source/anchors/\n```\n\n3. If a package is accidentally removed or you need to restore a file that is included in an **rpm** package, having a list of **rhel** packages installed on the system can be useful.\n\n **NOTE**\n\n If you use Red Hat Satellite features, such as content views or the facts store, provide a proper mechanism to reinstall the missing packages and a historical data of packages installed in the systems.\n\n To create a list of the current **rhel** packages installed in the system:\n4. If you used the previous steps, the following files are present in the backup directory:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo find $MYBACKUPDIR -mindepth 1 -type f -printf '%P\\n'\n```\n\ne tc/sysconfig/atomic-openshift-master\netc/sysconfig/atomic-openshift-master-api\netc/sysconfig/atomic-openshift-master-controllers\netc/sysconfig/atomic-openshift-node\netc/sysconfig/flanneld\netc/sysconfig/iptables\netc/sysconfig/docker-network\netc/sysconfig/docker-storage\netc/sysconfig/docker-storage-setup\netc/sysconfig/docker-storage-setup.rpmnew\netc/origin/master/ca.crt\netc/origin/master/ca.key\netc/origin/master/ca.serial.txt\netc/origin/master/ca-bundle.crt\netc/origin/master/master.proxy-client.crt\netc/origin/master/master.proxy-client.key\netc/origin/master/service-signer.crt\netc/origin/master/service-signer.key\netc/origin/master/serviceaccounts.private.key\netc/origin/master/serviceaccounts.public.key\netc/origin/master/openshift-master.crt\netc/origin/master/openshift-master.key\netc/origin/master/openshift-master.kubeconfig\netc/origin/master/master.server.crt\netc/origin/master/master.server.key\netc/origin/master/master.kubelet-client.crt\netc/origin/master/master.kubelet-client.key\netc/origin/master/admin.crt\netc/origin/master/admin.key\netc/origin/master/admin.kubeconfig\netc/origin/master/etcdf.server.crt\netc/origin/master/etcdf.server.key\netc/origin/master/master.etcd-client.key\netc/origin/master/master.etcd-client.csr\netc/origin/master/master.etcd-client.crt\netc/origin/master/master.etcd-ca.crt\netc/origin/master/policy.json\netc/origin/master/scheduler.json\netc/origin/master/htpasswd\netc/origin/master/session-secrets.yaml\netc/origin/master/openshift-router.crt\netc/origin/master/openshift-router.key\netc/origin/master/registry.crt\netc/origin/master/registry.key\netc/origin/master/master-config.yaml\netc/origin/generated-configs/master-master-1.example.com/master.server.crt\n...[OUTPUT OMITTED]...\nIf needed, you can compress the files to save space:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo tar -zcvf /backup/$(hostname)-$(date +%Y%m%d).tar.gz $MYBACKUPDIR\n$ sudo rm -Rf ${MYBACKUPDIR}\n```\n\nTo create any of these files from scratch, the `openshift-ansible-contrib` repository contains the `backup_master_node.sh` script, which performs the previous steps. The script creates a directory on the host where you run the script and copies all the files previously mentioned.\n\n**NOTE**\n\nThe `openshift-ansible-contrib` script is not supported by Red Hat, but the reference architecture team performs testing to ensure the code operates as defined and is secure.\n\nYou can run the script on every master host with:\n\n```bash\n$ mkdir ~/git\n$ cd ~/git\n$ git clone https://github.com/openshift/openshift-ansible-contrib.git\n$ cd openshift-ansible-contrib/reference-architecture/day2ops/scripts\n$ ./backup_master_node.sh -h\n```\n\n### 5.2.3. Restoring a master host backup\n\nAfter creating a backup of important master host files, if they become corrupted or accidentally removed, you can restore the files by copying the files back to master, ensuring they contain the proper content, and restarting the affected services.\n\n**Procedure**\n\n1. Restore the `/etc/origin/master/master-config.yaml` file:\n# MYBACKUPDIR=*/backup/$(hostname)/$(date +%Y%m%d)*\n# cp /etc/origin/master/master-config.yaml /etc/origin/master/master-config.yaml.old\n# cp /backup/$(hostname)/$(date +%Y%m%d)/origin/master/master-config.yaml\n/etc/origin/master/master-config.yaml\n# systemctl restart atomic-openshift-master-api\n# systemctl restart atomic-openshift-master-controllers\n\n## WARNING\n\nRestarting the master services can lead to downtime. However, you can remove the master host from the highly available load balancer pool, then perform the restore operation. Once the service has been properly restored, you can add the master host back to the load balancer pool.\n\n## NOTE\n\nPerform a full reboot of the affected instance to restore the `iptables` configuration.\n\n2. If you cannot restart OpenShift Container Platform because packages are missing, reinstall the packages.\n a. Get the list of the current installed packages:\n ```\n $ rpm -qa | sort > /tmp/current_packages.txt\n ```\n b. View the differences between the package lists:\n ```\n $ diff /tmp/current_packages.txt ${MYBACKUPDIR}/packages.txt\n > ansible-2.4.0.0-5.el7.noarch\n ```\n c. Reinstall the missing packages:\n ```\n # yum reinstall -y <packages>\n ```\n\n3. Restore a system certificate by copying the certificate to the `/etc/pki/ca-trust/source/anchors/` directory and execute the `update-ca-trust`:\n ```\n $ MYBACKUPDIR=*/backup/$(hostname)/$(date +%Y%m%d)*\n $ sudo cp ${MYBACKUPDIR}/external_certificates/my_company.crt /etc/pki/ca-trust/source/anchors/\n $ sudo update-ca-trust\n ```\nNOTE\n\nAlways ensure the user ID and group ID are restored when the files are copied back, as well as the SELinux context.\n\n5.3. NODE HOST TASKS\n\n5.3.1. Deprecating a node host\n\nThe procedure is the same whether deprecating an infrastructure node or an application node.\n\nPrerequisites\n\nEnsure enough capacity is available to migrate the existing pods from the node set to be removed. Removing an infrastructure node is advised only when at least two more nodes will stay online after the infrastructure node is removed.\n\nProcedure\n\n1. List all available nodes to find the node to deprecate:\n\n \n $ oc get nodes\n NAME STATUS AGE VERSION\n ocp-infra-node-b7pl Ready 23h v1.6.1+5115d708d7\n ocp-infra-node-p5zj Ready 23h v1.6.1+5115d708d7\n ocp-infra-node-rghb Ready 23h v1.6.1+5115d708d7\n ocp-master-dgf8 Ready,SchedulingDisabled 23h v1.6.1+5115d708d7\n ocp-master-q1v2 Ready,SchedulingDisabled 23h v1.6.1+5115d708d7\n ocp-master-vq70 Ready,SchedulingDisabled 23h v1.6.1+5115d708d7\n ocp-node-020m Ready 23h v1.6.1+5115d708d7\n ocp-node-7t5p Ready 23h v1.6.1+5115d708d7\n ocp-node-n0dd Ready 23h v1.6.1+5115d708d7\n\n As an example, this topic deprecates the ocp-infra-node-b7pl infrastructure node.\n\n2. Describe the node and its running services:\n\n \n $ oc describe node ocp-infra-node-b7pl\n Name: ocp-infra-node-b7pl\n Role:\n Labels: beta.kubernetes.io/arch=amd64\n beta.kubernetes.io/instance-type=n1-standard-2\n beta.kubernetes.io/os=linux\n failure-domain.beta.kubernetes.io/region=europe-west3\n failure-domain.beta.kubernetes.io/zone=europe-west3-c\n kubernetes.io/hostname=ocp-infra-node-b7pl\n role=infra\n Annotations: volumes.kubernetes.io/controller-managed-attach-detach=true\n Taints: <none>\n CreationTimestamp: Wed, 22 Nov 2017 09:36:36 -0500\n Phase:\n Conditions: ...\n Addresses: 10.156.0.11,ocp-infra-node-b7pl\n Capacity:\n cpu: 2\nmemory: 7494480Ki\npods: 20\nAllocatable:\ncpu: 2\nmemory: 7392080Ki\npods: 20\n\nSystem Info:\nMachine ID: bc95ccf67d047f2ae42c67862c202e44\nSystem UUID: 9762CC3D-E23C-AB13-B8C5-FA16F0BCCE4C\nBoot ID: ca8b0f88-905d-4ec0-beec-8f89f4527ce4\nKernel Version: 3.10.0-693.5.2.el7.x86_64\nOS Image: Employee SKU\nOperating System: linux\nArchitecture: amd64\nContainer Runtime Version: docker://1.12.6\nKubelet Version: v1.6.1+5115d708d7\nKube-Proxy Version: v1.6.1+5115d708d7\nExternalID: 437740049672994824\nNon-terminated Pods: (2 in total)\n<table>\n<thead>\n<tr>\n<th>Namespace</th>\n<th>Name</th>\n<th>CPU Requests</th>\n<th>CPU Limits</th>\n<th>Memory Requests</th>\n<th>Memory Limits</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>default</td>\n<td>docker-registry-1-5szjs</td>\n<td>100m (5%)</td>\n<td>0 (0%)</td>\n<td>256Mi (3%)</td>\n<td>0 (0%)</td>\n</tr>\n<tr>\n<td>default</td>\n<td>router-1-vzlzq</td>\n<td>100m (5%)</td>\n<td>0 (0%)</td>\n<td>256Mi (3%)</td>\n<td>0 (0%)</td>\n</tr>\n</tbody>\n</table>\n\nAllocated resources:\n(Total limits may be over 100 percent, i.e., overcommitted.)\n<table>\n<thead>\n<tr>\n<th>CPU Requests</th>\n<th>CPU Limits</th>\n<th>Memory Requests</th>\n<th>Memory Limits</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>200m (10%)</td>\n<td>0 (0%)</td>\n<td>512Mi (7%)</td>\n<td>0 (0%)</td>\n</tr>\n</tbody>\n</table>\n\nEvents: <none>\n\nThe output above shows that the node is running two pods: \\texttt{router-1-vzlzq} and \\texttt{docker-registry-1-5szjs}. Two more infrastructure nodes are available to migrate these two pods.\n\n\\textbf{NOTE}\n\nThe cluster described above is a highly available cluster, this means both the router and docker-registry services are running on all infrastructure nodes.\n\n3. Mark a node as unschedulable and evacuate all of its pods:\n\n```bash\n$ oc adm drain ocp-infra-node-b7pl --delete-local-data\nnode \"ocp-infra-node-b7pl\" cordoned\nWARNING: Deleting pods with local storage: docker-registry-1-5szjs\npod \"docker-registry-1-5szjs\" evicted\npod \"router-1-vzlzq\" evicted\nnode \"ocp-infra-node-b7pl\" drained\n```\n\nIf the pod has attached local storage (for example, \\texttt{EmptyDir}), the \\texttt{--delete-local-data} option must be provided. Generally, pods running in production should use the local storage only for temporary or cache files, but not for anything important or persistent. For regular storage, applications should use object storage or persistent volumes. In this case, the docker-registry pod’s local storage is empty, because the object storage is used instead to store the container images.\nNOTE\n\nThe above operation deletes existing pods running on the node. Then, new pods\nare created according to the replication controller.\n\nIn general, every application should be deployed with a deployment\nconfiguration, which creates pods using the replication controller.\n\n`oc adm drain` will not delete any bare pods (pods that are neither mirror pods\nnor managed by `ReplicationController`, `ReplicaSet`, `DaemonSet`, `StatefulSet`, or\na job). To do so, the `--force` option is required. Be aware that the bare pods will\nnot be recreated on other nodes and data may be lost during this operation.\n\nThe example below shows the output of the replication controller of the registry:\n\n```\n$ oc describe rc/docker-registry-1\nName: docker-registry-1\nNamespace: default\nSelector: deployment=docker-registry-1,deploymentconfig=docker-registry,docker-registry=default\nLabels: docker-registry=default\nopenshift.io/deployment-config.name=docker-registry\nAnnotations: ...\nReplicas: 3 current / 3 desired\nPods Status: 3 Running / 0 Waiting / 0 Succeeded / 0 Failed\nPod Template:\n Labels: deployment=docker-registry-1\ndeploymentconfig=docker-registry\ndocker-registry=default\nAnnotations: openshift.io/deployment-config.latest-version=1\nopenshift.io/deployment-config.name=docker-registry\nopenshift.io/deployment.name=docker-registry-1\nService Account: registry\nContainers:\n registry:\n Image: openshift3/ose-docker-registry:v3.6.173.0.49\n Port: 5000/TCP\n Requests:\n cpu: 100m\n memory: 256Mi\n Liveness: http-get https://:5000/healthz delay=10s timeout=5s period=10s #success=1\n Environment:\n REGISTRY_HTTP_ADDR: :5000\n REGISTRY_HTTP_NET: tcp\n REGISTRY_HTTP_SECRET: tyGEnDZmc8dQfioP3WkNd5z+Xbdfy/JVXf/NLo3s/zE=\n REGISTRY_MIDDLEWARE_REPOSITORY_OPENSHIFT_ENFORCERQUOTA: false\n REGISTRY_HTTP_TLS_KEY: /etc/secrets/registry.key\n REGISTRY_MIDDLEWARE_REPOSITORY_OPENSHIFT_ENFORCERQUOTA: false\n OPENSHIFT_DEFAULT_REGISTRY: docker-registry.default.svc:5000\n REGISTRY_CONFIGURATION_PATH: /etc/registry/config.yml\n REGISTRY_HTTP_TLS_CERTIFICATE: /etc/secrets/registry.crt\n Mounts:\n /etc/registry from docker-config (rw)\n /etc/secrets from registry-certificates (rw)\n```\n/registry from registry-storage (rw)\n\nVolumes:\nregistry-storage:\n Type: EmptyDir (a temporary directory that shares a pod's lifetime)\n Medium:\nregistry-certificates:\n Type: Secret (a volume populated by a Secret)\n SecretName: registry-certificates\n Optional: false\ndocker-config:\n Type: Secret (a volume populated by a Secret)\n SecretName: registry-config\n Optional: false\n\nEvents:\n FirstSeen LastSeen Count From SubObjectPath Type Reason Message\n --------- -------- ----- ------------- ------------- -------- ------- ---------------\n 49m 49m 1 replication-controller Normal SuccessfulCreate Created pod: docker-registry-1-dprp5\n\nThe event at the bottom of the output displays information about new pod creation. So, when listing all pods:\n\n$ oc get pods\nNAME READY STATUS RESTARTS AGE\n---------- -------- -------- -------- ----\ndocker-registry-1-dprp5 1/1 Running 0 52m\ndocker-registry-1-kr8jq 1/1 Running 0 1d\ndocker-registry-1-ncpl2 1/1 Running 0 1d\nregistry-console-1-g4nqg 1/1 Running 0 1d\nrouter-1-2gshr 0/1 Pending 0 52m\nrouter-1-85qm4 1/1 Running 0 1d\nrouter-1-q5sr8 1/1 Running 0 1d\n\n4. The docker-registry-1-5szjs and router-1-vzlzq pods that were running on the now deprecated node are no longer available. Instead, two new pods have been created: docker-registry-1-dprp5 and router-1-2gshr. As shown above, the new router pod is router-1-2gshr, but is in the Pending state. This is because every node can be running only on one single router and is bound to the ports 80 and 443 of the host.\n\n5. When observing the newly created registry pod, the example below shows that the pod has been created on the ocp-infra-node-rghb node, which is different from the deprecating node:\n\n$ oc describe pod docker-registry-1-dprp5\nName: docker-registry-1-dprp5\nNamespace: default\nSecurity Policy: hostnetwork\nNode: ocp-infra-node-rghb/10.156.0.10\n...\n\nThe only difference between deprecating the infrastructure and the application node is that once the infrastructure node is evacuated, and if there is no plan to replace that node, the services running on infrastructure nodes can be scaled down:\n\n$ oc scale dc/router --replicas 2\ndeploymentconfig \"router\" scaled\n$ oc scale dc/docker-registry --replicas 2\ndeploymentconfig \"docker-registry\" scaled\n\n6. Now, every infrastructure node is running only one kind of each pod:\n\n$ oc get pods\nNAME READY STATUS RESTARTS AGE\ndocker-registry-1-kr8jq 1/1 Running 0 1d\ndocker-registry-1-ncpl2 1/1 Running 0 1d\nregistry-console-1-g4nqg 1/1 Running 0 1d\nrouter-1-85qm4 1/1 Running 0 1d\nrouter-1-q5sr8 1/1 Running 0 1d\n\n$ oc describe po/docker-registry-1-kr8jq | grep Node:\nNode: ocp-infra-node-p5zj/10.156.0.9\n\n$ oc describe po/docker-registry-1-ncpl2 | grep Node:\nNode: ocp-infra-node-rghb/10.156.0.10\n\nNOTE\nTo provide a full highly available cluster, at least three infrastructure nodes\nshould always be available.\n\n7. To verify that the scheduling on the node is disabled:\n\n$ oc get nodes\nNAME STATUS AGE VERSION\nocp-infra-node-b7pl Ready,SchedulingDisabled 1d v1.6.1+5115d708d7\nocp-infra-node-p5zj Ready 1d v1.6.1+5115d708d7\nocp-infra-node-rghb Ready 1d v1.6.1+5115d708d7\nocp-master-dgf8 Ready,SchedulingDisabled 1d v1.6.1+5115d708d7\nocp-master-q1v2 Ready,SchedulingDisabled 1d v1.6.1+5115d708d7\nocp-master-vq70 Ready,SchedulingDisabled 1d v1.6.1+5115d708d7\nocp-node-020m Ready 1d v1.6.1+5115d708d7\nocp-node-7t5p Ready 1d v1.6.1+5115d708d7\nocp-node-n0dd Ready 1d v1.6.1+5115d708d7\n\nAnd that the node does not contain any pods:\n\n$ oc describe node ocp-infra-node-b7pl\nName: ocp-infra-node-b7pl\nRole:\nLabels: beta.kubernetes.io/arch=amd64\n beta.kubernetes.io/instance-type=n1-standard-2\n beta.kubernetes.io/os=linux\n failure-domain.beta.kubernetes.io/region=europe-west3\n failure-domain.beta.kubernetes.io/zone=europe-west3-c\n kubernetes.io/hostname=ocp-infra-node-b7pl\n role=infra\nAnnotations: volumes.kubernetes.io/controller-managed-attach-detach=true\nTaints: <none>\nCreationTimestamp: Wed, 22 Nov 2017 09:36:36 -0500\nPhase:\nConditions:\n\nAddresses: 10.156.0.11, ocp-infra-node-b7pl\n\nCapacity:\ncpu: 2\nmemory: 7494480Ki\npods: 20\n\nAllocatable:\ncpu: 2\nmemory: 7392080Ki\npods: 20\n\nSystem Info:\nMachine ID: bc95ccf67d047f2ae42c67862c202e44\nSystem UUID: 9762CC3D-E23C-AB13-B8C5-FA16F0BCCE4C\nBoot ID: ca8bf088-905d-4ec0-beec-8f89f4527ce4\nKernel Version: 3.10.0-693.5.2.el7.x86_64\nOS Image: Employee SKU\nOperating System: linux\nArchitecture: amd64\nContainer Runtime Version: docker://1.12.6\nKubelet Version: v1.6.1+5115d708d7\nKube-Proxy Version: v1.6.1+5115d708d7\nExternalID: 437740049672994824\n\nNon-terminated Pods: (0 in total)\n\n<table>\n<thead>\n<tr>\n<th>Namespace</th>\n<th>Name</th>\n<th>CPU Requests</th>\n<th>CPU Limits</th>\n<th>Memory Requests</th>\n<th>Memory Limits</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nAllocated resources:\n(Total limits may be over 100 percent, i.e., overcommitted.)\n\n<table>\n<thead>\n<tr>\n<th>CPU Requests</th>\n<th>CPU Limits</th>\n<th>Memory Requests</th>\n<th>Memory Limits</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n0 (0%) 0 (0%) 0 (0%) 0 (0%)\n\nEvents: <none>\n\n8. Remove the infrastructure instance from the backend section in the /etc/haproxy/haproxy.cfg configuration file:\n\n```bash\nbackend router80\n balance source\n mode tcp\n server infra-1.example.com 192.168.55.12:80 check\n server infra-2.example.com 192.168.55.13:80 check\n\nbackend router443\n balance source\n mode tcp\n server infra-1.example.com 192.168.55.12:443 check\n server infra-2.example.com 192.168.55.13:443 check\n```\n\n9. Then, restart the haproxy service.\n\n `$ sudo systemctl restart haproxy`\n\n10. Remove the node from the cluster after all pods are evicted with command:\n5.3.1. Replacing a node host\n\nIn the event that a node would need to be added in place of the deprecated node, follow the Adding hosts to an existing cluster section.\n\n5.3.2. Creating a node host backup\n\nCreating a backup of a node host is a different use case from backing up a master host. Because master hosts contain many important files, creating a backup is highly recommended. However, the nature of nodes is that anything special is replicated over the nodes in case of failover, and they typically do not contain data that is necessary to run an environment. If a backup of a node contains something necessary to run an environment, then a creating a backup is recommended.\n\nThe backup process is to be performed before any change to the infrastructure, such as a system update, upgrade, or any other significant modification. Backups should be performed on a regular basis to ensure the most recent data is available if a failure occurs.\n\nOpenShift Container Platform files\n\nNode instances run applications in the form of pods, which are based on containers. The /etc/origin/ and /etc/origin/node directories house important files, such as:\n\n- The configuration of the node services\n- Certificates generated by the installation\n- Cloud provider-related configuration\n- Keys and other authentication files, such as the dnsmasq configuration\n\nThe OpenShift Container Platform services can be customized to increase the log level, use proxies, and more, and the configuration files are stored in the /etc/sysconfig directory.\n\nProcedure\n\n1. Create a backup of the node configuration files:\n2. OpenShift Container Platform uses specific files that must be taken into account when planning the backup policy, including:\n\n<table>\n<thead>\n<tr>\n<th>File</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/etc/cni/*</td>\n<td>Container Network Interface configuration (if used)</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/iptables</td>\n<td>Where the <strong>iptables</strong> rules are stored</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker-storage-setup</td>\n<td>The input file for <strong>container-storage-setup</strong> command</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker</td>\n<td>The <strong>docker</strong> configuration file</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker-network</td>\n<td><strong>docker</strong> networking configuration (i.e. MTU)</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/docker-storage</td>\n<td><strong>docker</strong> storage configuration (generated by <strong>container-storage-setup</strong>)</td>\n</tr>\n<tr>\n<td>/etc/dnsmasq.conf</td>\n<td>Main configuration file for <strong>dnsmasq</strong></td>\n</tr>\n<tr>\n<td>/etc/dnsmasq.d/*</td>\n<td>Different <strong>dnsmasq</strong> configuration files</td>\n</tr>\n<tr>\n<td>/etc/sysconfig/flanneld</td>\n<td><strong>flannel</strong> configuration file (if used)</td>\n</tr>\n<tr>\n<td>/etc/pki/ca-trust/source/anchors/*</td>\n<td>Certificates added to the system (i.e. for external registries)</td>\n</tr>\n</tbody>\n</table>\n\nTo create those files:\n\n```\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo mkdir -p ${MYBACKUPDIR}/etc/sysconfig\n$ sudo mkdir -p ${MYBACKUPDIR}/etc/pki/ca-trust/source/anchors\n$ sudo cp -aR /etc/sysconfig/*etc/origin ${MYBACKUPDIR}/etc\n$ sudo cp -aR /etc/sysconfig/atomic-openshift-node ${MYBACKUPDIR}/etc/sysconfig/\n```\n\n3. If a package is accidentally removed, or a file included in an **rpm** package should be restored, having a list of **rhel** packages installed on the system can be useful.\nNOTE\n\nIf using Red Hat Satellite features, such as content views or the facts store, provide a proper mechanism to reinstall the missing packages and a historical data of packages installed in the systems.\n\nTo create a list of the current `rhel` packages installed in the system:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo mkdir -p ${MYBACKUPDIR}\n$ rpm -qa | sort | sudo tee $MYBACKUPDIR/packages.txt\n```\n\n4. The following files should now be present in the backup directory:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo find ${MYBACKUPDIR} -mindepth 1 -type f -printf '%P\n'\n/etc/sysconfig/atomic-openshift-node\n/etc/sysconfig/flanneld\n/etc/sysconfig/iptables\n/etc/sysconfig/docker-network\n/etc/sysconfig/docker-storage\n/etc/sysconfig/docker-storage-setup\n/etc/sysconfig/docker-storage-setup.rpmnew\n/etc/origin/node/system:node:app-node-0.example.com.crt\n/etc/origin/node/system:node:app-node-0.example.com.key\n/etc/origin/node/ca.crt\n/etc/origin/node/system:node:app-node-0.example.com.kubeconfig\n/etc/origin/node/server.crt\n/etc/origin/node/server.key\n/etc/origin/node/node-dnsmasq.conf\n/etc/origin/node/resolv.conf\n/etc/origin/node/node-config.yaml\n/etc/origin/node/flannel.etcd-client.key\n/etc/origin/node/flannel.etcd-client.csr\n/etc/origin/node/flannel.etcd-client.crt\n/etc/origin/node/flannel.etcd-ca.crt\n/etc/origin/cloudprovider/openstack.conf\n/etc/pki/ca-trust/source/anchors/openshift-ca.crt\n/etc/pki/ca-trust/source/anchors/registry-ca.crt\n/etc/dnsmasq.conf\n/etc/dnsmasq.d/origin-dns.conf\n/etc/dnsmasq.d/node-dnsmasq.conf\netc/dnmasq.d/node-dnmasq.conf\npackages.txt\n```\n\nIf needed, the files can be compressed to save space:\n\n```bash\n$ MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n$ sudo tar -zcvf /backup/$(hostname)-$(date +%Y%m%d).tar.gz $MYBACKUPDIR\n$ sudo rm -Rf ${MYBACKUPDIR}\n```\n\nTo create any of these files from scratch, the `openshift-ansible-contrib` repository contains the `backup_master_node.sh` script, which performs the previous steps. The script creates a directory on the host running the script and copies all the files previously mentioned.\nThe **openshift-ansible-contrib** script is not supported by Red Hat, but the reference architecture team performs testing to ensure the code operates as defined and is secure.\n\nThe script can be executed on every master host with:\n\n```\n$ mkdir ~/git\n$ cd ~/git\n$ git clone https://github.com/openshift/openshift-ansible-contrib.git\n$ cd openshift-ansible-contrib/reference-architecture/day2ops/scripts\n$ ./backup_master_node.sh -h\n```\n\n### 5.3.3. Restoring a node host backup\n\nAfter creating a backup of important node host files, if they become corrupted or accidentally removed, you can restore the file by copying back the file, ensuring it contains the proper content and restart the affected services.\n\n**Procedure**\n\n1. Restore the `/etc/origin/node/node-config.yaml` file:\n\n ```\n # MYBACKUPDIR=/backup/$(hostname)/$(date +%Y%m%d)\n # cp /etc/origin/node/node-config.yaml /etc/origin/node/node-config.yaml.old\n # cp /backup/$(hostname)/$(date +%Y%m%d)/etc/origin/node/node-config.yaml /etc/origin/node/node-config.yaml\n # systemctl restart atomic-openshift-node\n ```\n\n**WARNING**\n\nRestarting the services can lead to downtime. See Node maintenance, for tips on how to ease the process.\n\n**NOTE**\n\nPerform a full reboot of the affected instance to restore the **iptables** configuration.\n\n1. If you cannot restart OpenShift Container Platform because packages are missing, reinstall the packages.\n a. Get the list of the current installed packages:\n\n ```\n $ rpm -qa | sort > /tmp/current_packages.txt\n ```\n b. View the differences between the package lists:\n$ diff /tmp/current_packages.txt ${MYBACKUPDIR}/packages.txt\n\n> ansible-2.4.0.0-5.el7.noarch\n\nc. Reinstall the missing packages:\n\n```bash\n# yum reinstall -y <packages>\n```\n\n1. Replace `<packages>` with the packages that are different between the package lists.\n\n2. Restore a system certificate by copying the certificate to the `/etc/pki/ca-trust/source/anchors/` directory and execute the `update-ca-trust`:\n\n```bash\n$ MYBACKUPDIR=*/backup/$(hostname)/$(date +%Y%m%d)*\n$ sudo cp ${MYBACKUPDIR}/etc/pki/ca-trust/source/anchors/my_company.crt /etc/pki/ca-trust/source/anchors/\n$ sudo update-ca-trust\n```\n\n**NOTE**\n\nAlways ensure proper user ID and group ID are restored when the files are copied back, as well as the **SELinux** context.\n\n### 5.3.4. Node maintenance and next steps\n\nSee [Managing nodes](#) or [Managing pods](#) topics for various node management options. These include:\n\n- Marking Nodes as Unschedulable or Schedulable\n- Evacuating Pods on Nodes\n- Setting Pod Disruption Budgets\n\nA node can reserve a portion of its resources to be used by specific components. These include the `kubelet`, `kube-proxy`, Docker, or other remaining system components such as `sshd` and `NetworkManager`. See the [Allocating node resources section in the Cluster Administrator guide](#) for more information.\n\n### 5.4. ETCD TASKS\n\n#### 5.4.1. etcd backup\n\netcd is the key value store for all object definitions, as well as the persistent master state. Other components watch for changes, then bring themselves into the desired state.\n\nOpenShift Container Platform versions prior to 3.5 use etcd version 2 (v2), while 3.5 and later use version 3 (v3). The data model between the two versions of etcd is different. etcd v3 can use both the v2 and v3 data models, whereas etcd v2 can only use the v2 data model. In an etcd v3 server, the v2 and v3 data stores exist in parallel and are independent.\n\nFor both v2 and v3 operations, you can use the `ETCDCTL_API` environment variable to use the proper API:\netcdctl -v\netcdctl version: 3.2.5\nAPI version: 2\n$ ETCDCTL_API=3 etcdctl version\netcdctl version: 3.2.5\nAPI version: 3.2\n\nSee Migrating etcd Data (v2 to v3) section in the OpenShift Container Platform 3.7 documentation for information about how to migrate to v3.\n\nThe etcd backup process is composed of two different procedures:\n\n- Configuration backup: Including the required etcd configuration and certificates\n- Data backup: Including both v2 and v3 data model.\n\nYou can perform the data backup process on any host that has connectivity to the etcd cluster, where the proper certificates are provided, and where the `etcdctl` tool is installed.\n\nNOTE\n\nThe backup files must be copied to an external system, ideally outside the OpenShift Container Platform environment, and then encrypted.\n\nNote that the etcd backup still has all the references to current storage volumes. When you restore etcd, OpenShift Container Platform starts launching the previous pods on nodes and reattaching the same storage. This process is no different than the process of when you remove a node from the cluster and add a new one back in its place. Anything attached to that node is reattached to the pods on whatever nodes they are rescheduled to.\n\n5.4.1.1. Backing up etcd\n\nWhen you back up etcd, you must back up both the etcd configuration files and the etcd data.\n\n5.4.1.1.1. Backing up etcd configuration files\n\nThe etcd configuration files to be preserved are all stored in the `/etc/etcd` directory of the instances where etcd is running. This includes the etcd configuration file (`/etc/etcd/etcd.conf`) and the required certificates for cluster communication. All those files are generated at installation time by the Ansible installer.\n\nProcedure\n\nFor each etcd member of the cluster, back up the etcd configuration.\n\n```\n$ ssh master-0\n# mkdir -p /backup/etcd-config-$(date +%Y%m%d)/\n# cp -R /etc/etcd/ /backup/etcd-config-$(date +%Y%m%d)/\n```\n\nNOTE\n\nThe certificates and configuration files on each etcd cluster member are unique.\n\n5.4.1.1.2. Backing up etcd data\nPrerequisites\n\nNOTE\n\nThe OpenShift Container Platform installer creates aliases to avoid typing all the flags named etcdctl2 for etcd v2 tasks and etcdctl3 for etcd v3 tasks. However, the etcdctl3 alias does not provide the full endpoint list to the etcdctl command, so the --endpoints option with all the endpoints must be provided.\n\nBefore backing up etcd:\n\n- etcdctl binaries should be available or, in containerized installations, the rhel7/etcd container should be available\n- Ensure connectivity with the etcd cluster (port 2379/tcp)\n- Ensure the proper certificates to connect to the etcd cluster\n\nProcedure\n\nNOTE\n\nWhile the etcdctl backup command is used to perform the backup, etcd v3 has no concept of a backup. Instead, you either take a snapshot from a live member with the etcdctl snapshot save command or copy the member/snap/db file from an etcd data directory.\n\nThe etcdctl backup command rewrites some of the metadata contained in the backup, specifically, the node ID and cluster ID, which means that in the backup, the node loses its former identity. To recreate a cluster from the backup, you create a new, single-node cluster, then add the rest of the nodes to the cluster. The metadata is rewritten to prevent the new node from joining an existing cluster.\n\nBack up the etcd data:\n\n- If you use the v2 API, take the following actions:\n a. Stop all etcd services:\n\n```\n# systemctl stop etcd.service\n```\n\n b. Create the etcd data backup and copy the etcd db file:\n\n```\n# mkdir -p /backup/etcd-$ date +%Y%m%d\n# etcdctl2 backup \\\n --data-dir /var/lib/etcd \\\n --backup-dir /backup/etcd-$ date +%Y%m%d\n# cp /var/lib/etcd/member/snap/db /backup/etcd-$ date +%Y%m%d\n```\n\n c. Start all etcd services:\n\n```\n# systemctl start etcd.service\n```\nIf you use the v3 API, run the following commands:\n\n### IMPORTANT\n\nBecause clusters upgraded from previous versions of OpenShift Container Platform might contain v2 data stores, back up both v2 and v3 datastores.\n\n**a. Back up etcd v3 data:**\n\n```bash\n# systemctl show etcd --property=ActiveState,SubState\n# mkdir -p /backup/etcd-$(date +%Y%m%d)\n# etcdctl3 snapshot save */backup/etcd-$(date +%Y%m%d)*/db\nSnapshot saved at /backup/etcd-<date>/db\n```\n\n**b. Back up etcd v2 data:**\n\n```bash\n# systemctl stop etcd.service\n# etcdctl2 backup\n --data-dir /var/lib/etcd\n --backup-dir /backup/etcd-$(date +%Y%m%d)\n# cp /var/lib/etcd/member/snap/db /backup/etcd-$(date +%Y%m%d)\n# systemctl start etcd.service\n```\n\n### NOTE\n\nThe `etcdctl snapshot save` command requires the etcd service to be running.\n\nIn these commands, a `/backup/etcd-<date>/` directory is created, where `<date>` represents the current date, which must be an external NFS share, S3 bucket, or any external storage location.\n\nIn the case of an all-in-one cluster, the etcd data directory is located in the `/var/lib/origin/openshift.local.etcd` directory.\n\n### 5.4.2. Restoring etcd\n\nThe restore procedure for etcd configuration files replaces the appropriate files, then restarts the service.\n\nIf an etcd host has become corrupted and the `/etc/etcd/etcd.conf` file is lost, restore it using:\n\n```bash\n$ ssh master-0\n # cp /backup/yesterday/master-0-files/etcd.conf /etc/etcd/etcd.conf\n # restorecon -Rv /etc/etcd/etcd.conf\n # systemctI restart etcd.service\n```\n\nIn this example, the backup file is stored in the `/backup/yesterday/master-0-files/etcd.conf` path where it can be used as an external NFS share, S3 bucket, or other storage solution.\n\n### 5.4.2.1. Restoring etcd v2 & v3 data\nThe following process restores healthy data files and starts the etcd cluster as a single node, then adds the rest of the nodes if an etcd cluster is required.\n\nProcedure\n\n1. Stop all etcd services:\n\n ```\n # systemctl stop etcd.service\n ```\n\n2. To ensure the proper backup is restored, delete the etcd directories:\n\n - To back up the current etcd data before you delete the directory, run the following command:\n\n ```\n # mv /var/lib/etcd /var/lib/etcd.old\n # mkdir /var/lib/etcd\n # chown -R etcd.etcd /var/lib/etcd/\n # restorecon -Rv /var/lib/etcd/\n ```\n\n - Or, to delete the directory and the etcd, data, run the following command:\n\n ```\n # rm -Rf /var/lib/etcd/*\n ```\n\n **NOTE**\n\n In an all-in-one cluster, the etcd data directory is located in the /var/lib/origin/openshift.local.etcd directory.\n\n3. Restore a healthy backup data file to each of the etcd nodes. Perform this step on all etcd hosts, including master hosts collocated with etcd.\n\n ```\n # cp -R /backup/etcd-xxx/* /var/lib/etcd/\n # mv /var/lib/etcd/db /var/lib/etcd/member/snap/db\n # chcon -R --reference /backup/etcd-xxx/* /var/lib/etcd/\n # chown -R etcd:etcd /var/lib/etcd/R\n ```\n\n4. Run the etcd service on each host, forcing a new cluster.\n\n This creates a custom file for the etcd service, which overwrites the execution command adding the `--force-new-cluster` option:\n\n ```\n # mkdir -p /etc/systemd/system/etcd.service.d/\n # echo \"[Service]\" > /etc/systemd/system/etcd.service.d/temp.conf\n # echo \"ExecStart=\" >> /etc/systemd/system/etcd.service.d/temp.conf\n # sed -n '/ExecStart/s/\"$/ --force-new-cluster\"/p' /usr/lib/systemd/system/etcd.service\n >> /etc/systemd/system/etcd.service.d/temp.conf\n \n # systemctl daemon-reload\n # systemctl restart etcd\n ```\n\n5. Check for error messages:\n\n ```\n $ journalctl -fu etcd.service\n ```\n6. Check for health status:\n\n```\n# etcdctl2 cluster-health\nmember 5ee217d17301 is healthy: got healthy result from https://192.168.55.8:2379\ncluster is healthy\n```\n\n7. Restart the etcd service in cluster mode:\n\n```\n# rm -f /etc/systemd/system/etcd.service.d/temp.conf\n# systemctl daemon-reload\n# systemctl restart etcd\n```\n\n8. Check for health status and member list:\n\n```\n# etcdctl2 cluster-health\nmember 5ee217d17301 is healthy: got healthy result from https://192.168.55.8:2379\ncluster is healthy\n```\n```\n# etcdctl2 member list\n5ee217d17301: name=master-0.example.com peerURLs=http://localhost:2380\nclientURLs=https://192.168.55.8:2379 isLeader=true\n```\n\n9. After the first instance is running, you can restore the rest of your etcd servers.\n\n### 5.4.2.1.1. Fix the peerURLs parameter\n\nAfter restoring the data and creating a new cluster, the peerURLs parameter shows localhost instead of the IP where etcd is listening for peer communication:\n\n```\n# etcdctl2 member list\n5ee217d17301: name=master-0.example.com peerURLs=http://localhost:2380\nclientURLs=https://192.168.55.8:2379 isLeader=true\n```\n\n**5.4.2.1.1.1. Procedure**\n\n1. Get the member ID using etcdctl member list:\n\n```\n`etcdctl member list`\n```\n\n2. Get the IP where etcd listens for peer communication:\n\n```\n$ ss -l4n | grep 2380\n```\n\n3. Update the member information with that IP:\n\n```\n# etcdctl2 member update 5ee217d17301 https://192.168.55.8:2380\nUpdated member with ID 5ee217d17301 in cluster\n```\n\n4. To verify, check that the IP is in the member list:\n$ etcdctl member list\n5ee217d17301: name=master-0.example.com peerURLs=https://192.168.55.8*:2380\nclientURLs=https://192.168.55.8:2379 isLeader=true\n\n5.4.2.2. Restoring etcd for v3\n\nThe restore procedure for v3 data is similar to the restore procedure for the v2 data.\n\nSnapshot integrity may be optionally verified at restore time. If the snapshot is taken with `etcdctl snapshot save`, it will have an integrity hash that is checked by `etcdctl snapshot restore`. If the snapshot is copied from the data directory, there is no integrity hash and it will only restore by using `--skip-hash-check`.\n\n**IMPORTANT**\n\nThe procedure to restore only the v3 data must be performed on a single etcd host. You can then add the rest of the nodes to the cluster.\n\n**Procedure**\n\n1. Stop all etcd services:\n\n ```bash\n # systemctl stop etcd.service\n ```\n\n2. Clear all old data, because `etcdctl` recreates it in the node where the restore procedure is going to be performed:\n\n ```bash\n # rm -Rf /var/lib/etcd\n ```\n\n3. Run the `snapshot restore` command, substituting the values from the `/etc/etcd/etcd.conf` file:\n\n ```bash\n # etcdctl snapshot restore /backup/etcd-xxxxxx/backup.db \\\n --data-dir /var/lib/etcd \\\n --name master-0.example.com \\\n --initial-cluster \"master-0.example.com=https://192.168.55.8:2380\" \\\n --initial-cluster-token \"etcd-cluster-1\" \\\n --initial-advertise-peer-urls https://192.168.55.8:2380\n ```\n\n4. Restore permissions and `selinux` context to the restored files:\n\n ```bash\n # chown -R etcd.etcd /var/lib/etcd/\n # restorecon -Rv /var/lib/etcd\n ```\n\n5. Start the etcd service:\n\n ```bash\n # systemctl start etcd\n ```\n\n6. Check for any error messages:\n5.4.3. Replacing an etcd host\n\nTo replace an etcd host, scale up the etcd cluster and then remove the host. This process ensures that you keep quorum if you lose an etcd host during the replacement procedure.\n\n**WARNING**\n\nThe etcd cluster must maintain a quorum during the replacement operation. This means that at least one host must be in operation at all times.\n\nIf the host replacement operation occurs while the etcd cluster maintains a quorum, cluster operations are usually not affected. If a large amount of etcd data must replicate, some operations might slow down.\n\n**NOTE**\n\nBefore you start any procedure involving the etcd cluster, you must have a backup of the etcd data and configuration files so that you can restore the cluster if the procedure fails.\n\n5.4.4. Scaling etcd\n\nYou can scale the etcd cluster vertically by adding more resources to the etcd hosts or horizontally by adding more etcd hosts.\n\n**NOTE**\n\nDue to the voting system etcd uses, the cluster must always contain an odd number of members.\n\nHaving a cluster with an odd number of etcd hosts can account for fault tolerance. Having an odd number of etcd hosts does not change the number needed for a quorum but increases the tolerance for failure. For example, with a cluster of three members, quorum is two, which leaves a failure tolerance of one. This ensures the cluster continues to operate if two of the members are healthy.\n\nHaving an in-production cluster of three etcd hosts is recommended.\n\nThe new host requires a fresh Red Hat Enterprise Linux version 7 dedicated host. The etcd storage should be located on an SSD disk to achieve maximum performance and on a dedicated disk mounted in `/var/lib/etcd`.\n\n**Prerequisites**\n\n1. Before you add a new etcd host, perform a backup of both etcd configuration and data to prevent data loss.\n\n2. Check the current etcd cluster status to avoid adding new hosts to an unhealthy cluster.\n• If you use the v2 etcd api, run this command:\n\n```bash\n# etcdctl --cert-file=/etc/etcd/peer.crt \\\n --key-file=/etc/etcd/peer.key \\\n --ca-file=/etc/etcd/ca.crt \\\n --peers=\"https://*master-0.example.com*:2379,\\n https://*master-1.example.com*:2379,\\n https://*master-2.example.com*:2379\" \\\n cluster-health\n```\n\nmember 5ee217d19001 is healthy: got healthy result from https://192.168.55.12:2379\nmember 2a529ba1840722c0 is healthy: got healthy result from https://192.168.55.8:2379\nmember ed4f0efd277d7599 is healthy: got healthy result from https://192.168.55.13:2379\ncluster is healthy\n\n• If you use the v3 etcd api, run this command:\n\n```bash\n# ETCDCTL_API=3 etcdctl --cert=\"/etc/etcd/peer.crt\" \\\n --key=\"/etc/etcd/peer.key\" \\\n --cacert=\"/etc/etcd/ca.crt\" \\\n --endpoints=\"https://*master-0.example.com*:2379,\\n https://*master-1.example.com*:2379,\\n https://*master-2.example.com*:2379\" \\\n endpoint health\n```\n\nhttps://master-0.example.com:2379 is healthy: successfully committed proposal: took = 5.011358ms\nhttps://master-1.example.com:2379 is healthy: successfully committed proposal: took = 1.305173ms\nhttps://master-2.example.com:2379 is healthy: successfully committed proposal: took = 1.388772ms\n\n3. Before running the `scaleup` playbook, ensure the new host is registered to the proper Red Hat software channels:\n\n```bash\n# subscription-manager register \\\n --username=\"*<username>* --password=\"*<password>*\n# subscription-manager attach --pool=\"*<poolid>*\n# subscription-manager repos --disable=\"*\"\n# subscription-manager repos \\\n --enable=rhel-7-server-rpms \\\n --enable=rhel-7-server-extras-rpms\n```\n\netcd is hosted in the `rhel-7-server-extras-rpms` software channel.\n\n4. Upgrade etcd and iptables on the current etcd nodes:\n\n```bash\n# yum update etcd iptables-services\n```\n\n5. Back up the `/etc/etcd` configuration for the etcd hosts.\n\n6. If the new etcd members will also be OpenShift Container Platform nodes, add the desired number of hosts to the cluster.\n\n7. The rest of this procedure assumes you added one host, but if you add multiple hosts, perform all steps on each host.\n5.4.4.1. Adding a new etcd host using Ansible\n\nProcedure\n\n1. In the Ansible inventory file, create a new group named [new_etcd] and add the new host. Then, add the new_etcd group as a child of the [OSEv3] group:\n\n ![inventory file content]\n\n Add these lines.\n\n2. From the host that installed OpenShift Container Platform and hosts the Ansible inventory file, run the etcd scaleup playbook:\n\n $ ansible-playbook /usr/share/ansible/openshift-ansible/playbooks/openshift-etcd/scaleup.yml\n\n3. After the playbook runs, modify the inventory file to reflect the current status by moving the new etcd host from the [new_etcd] group to the [etcd] group:\n\n ![inventory file content]\n\n4. If you use the service catalog, you must update its list of etcd servers:\n\n $ oc edit ds apiserver -n kube-service-catalog\n\n Add the FQDN for the new etcd node to the --etcd-servers argument. This argument contains a comma-separated list.\n5. If you use Flannel, modify the `flanneld` service configuration on every OpenShift Container Platform host, located at `/etc/sysconfig/flanneld`, to include the new etcd host:\n\n```\n```\n\n6. Restart the `flanneld` service:\n\n```bash\n# systemctl restart flanneld.service\n```\n\n### 5.4.4.2. Manually adding a new etcd host\n\n#### Procedure\n\n**Modify the current etcd cluster**\n\nTo create the etcd certificates, run the `openssl` command, replacing the values with those from your environment.\n\n1. Create some environment variables:\n\n```bash\nexport NEW_ETCD_HOSTNAME=\"*etcd0.example.com*\"\nexport NEW_ETCD_IP=\"192.168.55.21\"\nexport CN=$NEW_ETCD_HOSTNAME\nexport SAN=\"IP:$NEW_ETCD_IP, DNS:$NEW_ETCD_HOSTNAME\"\nexport PREFIX=\"/etc/etcd/generated_certs/etcd-$CN/\"\nexport OPENSSLCFG=\"/etc/etcd/ca/openssl.cnf\"\n```\n\n**NOTE**\n\nThe custom `openssl` extensions used as `etcd_v3_ca_*` include the `$SAN` environment variable as `subjectAltName`. See `/etc/etcd/ca/openssl.cnf` for more information.\n\n2. Create the directory to store the configuration and certificates:\n\n```bash\n# mkdir -p $PREFIX\n```\n\n3. Create the server certificate request and sign it: (`server.csr` and `server.crt`)\n\n```bash\n# openssl req -new -config $OPENSSLCFG \\\\ \n- keyout $PREFIX/server.key \\\\ \n- out $PREFIX/server.csr \\\\ \n- reqexts etcd_v3_req -batch -nodes \\\\ \n- subj /CN=$CN\n\n# openssl ca -name etcd_ca -config $OPENSSLCFG \\\\ \n- out $PREFIX/server.crt \\\\ \n- in $PREFIX/server.csr \\\\ \n- extensions etcd_v3_ca_server -batch\n```\n\n4. Create the peer certificate request and sign it: (`peer.csr` and `peer.crt`)\n\n```bash\n# openssl req -new -config $OPENSSLCFG \\\\ \n```\n1. -keyout ${PREFIX}peer.key \\\n -out ${PREFIX}peer.csr \\\n -reqexts etcd_v3_req -batch -nodes \\\n -subj /CN=$CN\n\n# openssl ca -name etcd_ca -config ${OPENSSLCFG} \\\n -out ${PREFIX}peer.crt \\\n -in ${PREFIX}peer.csr \\\n -extensions etcd_v3_ca_peer -batch\n\n5. Copy the current etcd configuration and ca.crt files from the current node as examples to modify later:\n\n# cp /etc/etcd/etcd.conf ${PREFIX}\n# cp /etc/etcd/ca.crt ${PREFIX}\n\n6. While still on the surviving etcd host, add the new host to the cluster. To add additional etcd members to the cluster, you must first adjust the default localhost peer in the peerURLs value for the first member:\n\na. Get the member ID for the first member using the member list command:\n\n# etcdctl --cert-file=/etc/etcd/peer.crt \\\n --key-file=/etc/etcd/peer.key \\\n --ca-file=/etc/etcd/ca.crt \\\n\n 1 member list\n\n 1 Ensure that you specify the URLs of only active etcd members in the --peers parameter value.\n\nb. Obtain the IP address where etcd listens for cluster peers:\n\n$ ss -l4n | grep 2380\n\nc. Update the value of peerURLs using the etcdctl member update command by passing the member ID and IP address obtained from the previous steps:\n\n# etcdctl --cert-file=/etc/etcd/peer.crt \\\n --key-file=/etc/etcd/peer.key \\\n --ca-file=/etc/etcd/ca.crt \\\n\n member update 511b7fb6cc0001 https://172.18.1.18:2380\n\nd. Re-run the member list command and ensure the peer URLs no longer include localhost.\n\n7. Add the new host to the etcd cluster. Note that the new host is not yet configured, so the status stays as unstarted until the you configure the new host.\nWARNING\n\nYou must add each member and bring it online one at a time. When you add each additional member to the cluster, you must adjust the `peerURLs` list for the current peers. The `peerURLs` list grows by one for each member added. The `etcdctl member add` command outputs the values that you must set in the `etcd.conf` file as you add each member, as described in the following instructions.\n\n```bash\n# etcdctl -C https://$(CURRENT_ETCD_HOST):2379 \\\n--ca-file=/etc/etcd/ca.crt \\\n--cert-file=/etc/etcd/peer.crt \\\n--key-file=/etc/etcd/peer.key member add ${NEW_ETCD_HOSTNAME} https://${NEW_ETCD_IP}:2380\n```\n\nAdded member named 10.3.9.222 with ID 4e1db163a21d7651 to cluster\n\n```\nETCD_NAME=\"<NEW_ETCD_HOSTNAME>\"\nETCD_INITIAL_CLUSTER=\"<NEW_ETCD_HOSTNAME>=https://<NEW_HOST_IP>:2380,\n<CLUSTERMEMBER1_NAME>=https://<CLUSTERMEMBER2_IP>:2380,\n<CLUSTERMEMBER2_NAME>=https://<CLUSTERMEMBER2_IP>:2380,\n<CLUSTERMEMBER3_NAME>=https://<CLUSTERMEMBER3_IP>:2380\"\nETCD_INITIAL_CLUSTER_STATE=\"existing\"\n```\n\n1 In this line, `10.3.9.222` is a label for the etcd member. You can specify the host name, IP address, or a simple name.\n\n8. Update the sample `$({PREFIX})/etcd.conf` file.\n\n a. Replace the following values with the values generated in the previous step:\n\n - `ETCD_NAME`\n - `ETCD_INITIAL_CLUSTER`\n - `ETCD_INITIAL_CLUSTER_STATE`\n\n b. Modify the following variables with the new host IP from the output of the previous step. You can use `$({NEW_ETCD_IP})` as the value.\n\n ```\n ETCD_LISTEN_PEER_URLS\n ETCD_LISTEN_CLIENT_URLS\n ETCD_INITIAL_ADVERTISE_PEER_URLS\n ETCD_ADVERTISE_CLIENT_URLS\n ```\n\n c. If you previously used the member system as an etcd node, you must overwrite the current values in the `/etc/etcd/etcd.conf` file.\n\n d. Check the file for syntax errors or missing IP addresses, otherwise the etcd service might fail:\n# vi $(PREFIX)/etcd.conf\n\n9. On the node that hosts the installation files, update the [etcd] hosts group in the `/etc/ansible/hosts` inventory file. Remove the old etcd hosts and add the new ones.\n\n10. Create a `tgz` file that contains the certificates, the sample configuration file, and the `ca` and copy it to the new host:\n\n```\n# tar -czvf /etc/etcd/generated_certs/${CN}.tgz -C ${PREFIX} .\n# scp /etc/etcd/generated_certs/${CN}.tgz ${CN}:/tmp/\n```\n\nModify the new etcd host\n\n1. Install `iptables-services` to provide iptables utilities to open the required ports for etcd:\n\n```\n# yum install -y iptables-services\n```\n\n2. Create the `OS_FIREWALL_ALLOW` firewall rules to allow etcd to communicate:\n\n - Port 2379/tcp for clients\n - Port 2380/tcp for peer communication\n\n```\n# systemctl enable iptables.service --now\n# iptables -N OS_FIREWALL_ALLOW\n# iptables -t filter -I INPUT -j OS_FIREWALL_ALLOW\n# iptables -A OS_FIREWALL_ALLOW -p tcp -m state --state NEW -m tcp --dport 2379 -j ACCEPT\n# iptables -A OS_FIREWALL_ALLOW -p tcp -m state --state NEW -m tcp --dport 2380 -j ACCEPT\n# iptables-save | tee /etc/sysconfig/iptables\n```\n\n**NOTE**\n\nIn this example, a new chain `OS_FIREWALL_ALLOW` is created, which is the standard naming the OpenShift Container Platform installer uses for firewall rules.\n\n**WARNING**\n\nIf the environment is hosted in an IaaS environment, modify the security groups for the instance to allow incoming traffic to those ports as well.\n\n3. Install etcd:\n\n```\n# yum install -y etcd\n```\n\nEnsure version `etcd-2.3.7-4.el7.x86_64` or greater is installed,\n4. Ensure the etcd service is not running:\n \n ```bash\n # systemctl disable etcd --now\n ```\n\n5. Remove any etcd configuration and data:\n \n ```bash\n # rm -Rf /etc/etcd/*\n # rm -Rf /var/lib/etcd/*\n ```\n\n6. Extract the certificates and configuration files:\n \n ```bash\n # tar xzvf /tmp/etcd0.example.com.tgz -C /etc/etcd/\n ```\n\n7. Modify the file ownership permissions:\n \n ```bash\n # chown -R etcd:etcd /etc/etcd/*\n # chown -R etcd:etcd /var/lib/etcd/\n ```\n\n8. Start etcd on the new host:\n \n ```bash\n # systemctl enable etcd --now\n ```\n\n9. Verify that the host is part of the cluster and the current cluster health:\n \n - If you use the v2 etcd api, run the following command:\n \n ```bash\n # etcdctl --cert-file=/etc/etcd/peer.crt \n --key-file=/etc/etcd/peer.key \n --ca-file=/etc/etcd/ca.crt \n --peers=\"https://*master-0.example.com*:2379, \n https://*master-1.example.com*:2379, \n https://*master-2.example.com*:2379, \n https://*etcd0.example.com*:2379\" \n cluster-health\n ```\n\n - If you use the v3 etcd api, run the following command:\n \n ```bash\n # ETCDCTL_API=3 etcdctl --cert=\"/etc/etcd/peer.crt\" \n --key=\"/etc/etcd/peer.key\" \n --cacert=\"/etc/etcd/ca.crt\" \n --endpoints=\"https://*master-0.example.com*:2379, \n https://*master-1.example.com*:2379, \n https://*master-2.example.com*:2379, \n https://*etcd0.example.com*:2379\" \n endpoint health\n ```\nModify each OpenShift Container Platform master\n\n1. Modify the master configuration in the `etcClientInfo` section of the `/etc/origin/master/master-config.yaml` file on every master. Add the new etcd host to the list of the etcd servers OpenShift Container Platform uses to store the data, and remove any failed etcd hosts:\n\n ```yaml\n etcdClientInfo:\n ca: master.etcd-ca.crt\n certFile: master.etcd-client.crt\n keyFile: master.etcd-client.key\n urls:\n - https://master-0.example.com:2379\n - https://master-1.example.com:2379\n - https://master-2.example.com:2379\n - https://etcd0.example.com:2379\n ```\n\n2. Restart the master API service:\n - On every master:\n ```bash\n # systemctl restart atomic-openshift-master-api\n ```\n - Or, on a single master cluster installation:\n ```bash\n # systemctl restart atomic-openshift-master\n ```\n\n **WARNING**\n The number of etcd nodes must be odd, so you must add at least two hosts.\n\n3. If you use Flannel, modify the `flanneld` service configuration located at `/etc/sysconfig/flanneld` on every OpenShift Container Platform host to include the new etcd host:\n\n ```bash\n ```\n\n4. Restart the `flanneld` service:\n ```bash\n # systemctl restart flanneld.service\n ```\n\n5.4.5. Removing an etcd host\nIf an etcd host fails beyond restoration, remove it from the cluster.\n\n**Steps to be performed on all masters hosts**\n\n**Procedure**\n\n1. Remove each other etcd host from the etcd cluster. Run the following command for each etcd node:\n\n```\n# etcdctl -C https://<surviving host IP address>:2379 \\\n--ca-file=/etc/etcd/ca.crt \\\n--cert-file=/etc/etcd/peer.crt \\\n--key-file=/etc/etcd/peer.key member remove <failed member ID>\n```\n\n2. Restart the master API service on every master:\n\n```\n# systemctl restart atomic-openshift-master-api\n```\n\nOr, if using a single master cluster installation:\n\n```\n# systemctl restart atomic-openshift-master\n```\n\n**Steps to be performed in the current etcd cluster**\n\n**Procedure**\n\n1. Remove the failed host from the cluster:\n\n```\n# etcdctl2 cluster-health\nmember 5ee217d19001 is healthy: got healthy result from https://192.168.55.12:2379\nmember 2a529ba1840722c0 is healthy: got healthy result from https://192.168.55.8:2379\nmember 8372784203e11288 is unreachable: [https://192.168.55.21:2379] are all unreachable\nmember ed4f0efd277d7599 is healthy: got healthy result from https://192.168.55.13:2379\ncluster is healthy\n```\n\n```\n# etcdctl2 member remove 8372784203e11288 ①\nRemoved member 8372784203e11288 from cluster\n```\n\n```\n# etcdctl2 cluster-health\nmember 5ee217d19001 is healthy: got healthy result from https://192.168.55.12:2379\nmember 2a529ba1840722c0 is healthy: got healthy result from https://192.168.55.8:2379\nmember ed4f0efd277d7599 is healthy: got healthy result from https://192.168.55.13:2379\ncluster is healthy\n```\n\n① The *remove* command requires the etcd ID, not the hostname.\n\n2. To ensure the etcd configuration does not use the failed host when the etcd service is restarted, modify the `/etc/etcd/etcd.conf` file on all remaining etcd hosts and remove the failed host in the value for the `ETCDInicial_CLUSTER` variable:\n# vi /etc/etcd/etcd.conf\n\nFor example:\n\n```bash\n```\n\nbecomes:\n\n```bash\nETCD_INITIAL_CLUSTER=master-0.example.com=https://192.168.55.8:2380,master-1.example.com=https://192.168.55.12:2380\n```\n\n**NOTE**\n\nRestarting the etcd services is not required, because the failed host is removed using `etcdctl`.\n\n3. Modify the Ansible inventory file to reflect the current status of the cluster and to avoid issues when re-running a playbook:\n\n```yaml\n[OSEv3:children]\nmasters\nnodes\netcd\n\n... [OUTPUT ABBREVIATED] ...\n\n[etcd]\nmaster-0.example.com\nmaster-1.example.com\n```\n\n4. If you are using Flannel, modify the `flanneld` service configuration located at `/etc/sysconfig/flanneld` on every host and remove the etcd host:\n\n```bash\n```\n\n5. Restart the `flanneld` service:\n\n```bash\n# systemctl restart flanneld.service\n```\nCHAPTER 6. PROJECT-LEVEL TASKS\n\n6.1. BACKING UP A PROJECT\n\nCreating a backup of all relevant data involves exporting all important information, then restoring into a new project.\n\nNOTE\n\nCurrently, a OpenShift Container Platform project back up and restore tool is being developed by Red Hat. See the following bug for more information:\n\n- bugzilla 1303205.\n\nProcedure\n\n1. List all the relevant data to back up:\n\n ```bash\n $ oc get all\n NAME TYPE FROM LATEST\n bc/ruby-ex Source Git 1\n \n NAME TYPE FROM STATUS STARTED DURATION\n builds/ruby-ex-1 Source Git@c457001 Complete 2 minutes ago 35s\n \n NAME DOCKER REPO TAGS UPDATED\n is/guestbook 10.111.255.221:5000/myproject/guestbook latest 2 minutes ago\n is/hello-openshift 10.111.255.221:5000/myproject/hello-openshift latest 2 minutes ago\n is/ruby-22-centos7 10.111.255.221:5000/myproject/ruby-22-centos7 latest 2 minutes ago\n is/ruby-ex 10.111.255.221:5000/myproject/ruby-ex latest 2 minutes ago\n \n NAME REVISION DESIRED CURRENT TRIGGERED BY\n dc/guestbook 1 1 1 config,image(guestbook:latest)\n dc/hello-openshift 1 1 1 config,image(hello-openshift:latest)\n dc/ruby-ex 1 1 1 config,image(ruby-ex:latest)\n \n NAME DESIRED CURRENT READY AGE\n rc/guestbook-1 1 1 1 2m\n rc/hello-openshift-1 1 1 1 2m\n rc/ruby-ex-1 1 1 1 2m\n \n NAME READY STATUS RESTARTS AGE\n po/guestbook-1-c010g 1/1 Running 0 2m\n po/hello-openshift-1-4zw2q 1/1 Running 0 2m\n po/ruby-ex-1-build 0/1 Completed 0 2m\n po/ruby-ex-1-rxc74 1/1 Running 0 2m\n ```\n\n2. Export the project objects to a `.yaml` or `.json` file.\nTo export the project objects into a `project.yaml` file:\n\n```\n$ oc export all -o yaml > project.yaml\n```\n\nTo export the project objects into a `project.json` file:\n\n```\n$ oc export all -o json > project.json\n```\n\n3. Export the project’s **role bindings, secrets, service accounts, and persistent volume claims**:\n\n```\n$ for object in rolebindings serviceaccounts secrets imagestreamtags podpreset cms egressnetworkpolicies rolebindingrestrictions limitranges resourcequotas pvcs templates cronjobs statefulsets hpas deployments replicaset endpoints do\n oc export $object -o yaml > $object.yaml\ndone\n```\n\n4. To list all the namespaced objects:\n\n```\n$ oc api-resources --namespaced=true -o name\n```\n\n5. Some exported objects can rely on specific metadata or references to unique IDs in the project. This is a limitation on the usability of the recreated objects.\n\nWhen using **imagestreams**, the `image` parameter of a **deploymentconfig** can point to a specific `sha` checksum of an image in the internal registry that would not exist in a restored environment. For instance, running the sample “ruby-ex” as `oc new-app centos/ruby-22-centos7~https://github.com/sclorg/ruby-ex.git` creates an imagestream `ruby-ex` using the internal registry to host the image:\n\n```\n$ oc get dc ruby-ex -o jsonpath=\"{.spec.template.spec.containers[].image}\"\n10.111.255.221:5000/myproject/ruby-ex@sha256:880c720b23c8d15a53b01db52f7abdcbb2280e03f686a5c8edfef1a2a7b21cee\n```\n\nIf importing the **deploymentconfig** as it is exported with `oc export` it fails if the image does not exist.\n\n### 6.2. RESTORING A PROJECT\n\nTo restore a project, create the new project, then restore any exported files by running `oc create -f pods.json`. However, restoring a project from scratch requires a specific order because some objects depend on others. For example, you must create the **configmaps** before you create any **pods**.\n\n**Procedure**\n\n1. If the project was exported as a single file, import it by running the following commands:\n\n```\n$ oc new-project <projectname>\n$ oc create -f project.yaml\n$ oc create -f secret.yaml\n$ oc create -f serviceaccount.yaml\n$ oc create -f pvcs.yaml\n$ oc create -f rolebindings.yaml\n```\n\nOpenShift Container Platform 3.9 Day Two Operations Guide\n6.2.1. Backing up persistent volume claims\n\nYou can synchronize persistent data from inside of a container to a server.\n\n**IMPORTANT**\n\nDepending on the provider that is hosting the OpenShift Container Platform environment, the ability to launch third party snapshot services for backup and restore purposes also exists. As OpenShift Container Platform does not have the ability to launch these services, this guide does not describe these steps.\n\nConsult any product documentation for the correct backup procedures of specific applications. For example, copying the mysql data directory itself does not create a usable backup. Instead, run the specific backup procedures of the associated application and then synchronize any data. This includes using snapshot solutions provided by the OpenShift Container Platform hosting platform.\n\n**Procedure**\n\n1. View the project and pods:\n\n ```\n $ oc get pods\n NAME READY STATUS RESTARTS AGE\n demo-1-build 0/1 Completed 0 2h\n demo-2-fxx6d 1/1 Running 0 1h\n ```\n\n2. Describe the desired pod to find the volumes that are currently used by a persistent volume:\n\n ```\n $ oc describe pod demo-2-fxx6d\n Name: demo-2-fxx6d\n Namespace: test\n Security Policy: restricted\n Node: ip-10-20-6-20.ec2.internal/10.20.6.20\n Start Time: Tue, 05 Dec 2017 12:54:34 -0500\n Labels: app=demo\n deployment=demo-2\n deploymentconfig=demo\n Status: Running\n IP: 172.16.12.5\n Controllers: ReplicationController/demo-2\n Containers:\n demo:\n Container ID: docker://201f3e55b373641eb36945d723e1e212ecab847311109b5ceef1fd0109424217a\n Image: docker-registry.default.svc:5000/test/demo@sha256:0a9f2487a0d95d51511e49d20dc9ff6f350436f935\n```\nThis output shows that the persistent data is in the `/opt/app-root/src/uploaded` directory.\n\n3. Copy the data locally:\n\n```\n$ oc rsync demo-2-fxx6d:/opt/app-root/src/uploaded ./demo-app\nreceiving incremental file list\nuploaded/\nuploaded/ocp_sop.txt\nuploaded/lost+found/\nsent 38 bytes received 190 bytes 152.00 bytes/sec\ntotal size is 32 speedup is 0.14\n```\n\nThe `ocp_sop.txt` file is downloaded to the local system to be backed up by backup software or another backup mechanism.\n\n**NOTE**\n\nYou can also use the previous steps if a pod starts without needing to use a PVC, but you later decide that a PVC is necessary. You can preserve the data and then use the restorative process to populate the new storage.\n\n### 6.2.2. Restoring persistent volume claims\n\nYou can restore persistent volume claim (PVC) data that you backed up. You can delete the file and then place the file back in the expected location or migrate the persistent volume claims. You might migrate if you need to move the storage or in a disaster scenario when the backend storage no longer exists.\n\nConsult any product documentation for the correct restoration procedures for specific applications.\n\n#### 6.2.2.1. Restoring files to an existing PVC\n\n**Procedure**\n\n1. Delete the file:\n\n```\n$ oc rsh demo-2-fxx6d\nsh-4.2$ ls */opt/app-root/src/uploaded/*\nlost+found ocp_sop.txt\n```\nsh-4.2$ *rm -rf /opt/app-root/src/uploaded/ocp_sop.txt*\nsh-4.2$ *ls /opt/app-root/src/uploaded/*\nlost+found\n\n2. Replace the file from the server that contains the rsync backup of the files that were in the pvc:\n\n```bash\n$ oc rsync uploaded demo-2-fxx6d:/opt/app-root/src/\n```\n\n3. Validate that the file is back on the pod by using `oc rsh` to connect to the pod and view the contents of the directory:\n\n```bash\n$ oc rsh demo-2-fxx6d\nsh-4.2$ *ls /opt/app-root/src/uploaded/*\nlost+found ocp_sop.txt\n```\n\n6.2.2.2. Restoring data to a new PVC\n\nThe following steps assume that a new PVC has been created.\n\n**Procedure**\n\n1. Overwrite the currently defined `claim-name`:\n\n```bash\n$ oc volume dc/demo --add --name=persistent-volume \\ --type=persistentVolumeClaim --claim-name=filestore \\ --mount-path=/opt/app-root/src/uploaded --overwrite\n```\n\n2. Validate that the pod is using the new PVC:\n\n```bash\n$ oc describe dc/demo\nName: demo\nNamespace: test\nCreated: 3 hours ago\nLabels: app=demo\nAnnotations: openshift.io/generated-by=OpenShiftNewApp\nLatest Version: 3\nSelector: app=demo,deploymentconfig=demo\nReplicas: 1\nTriggers: Config, Image(demo@latest, auto=true)\nStrategy: Rolling\nTemplate:\n Labels: app=demo\n deploymentconfig=demo\n Annotations: openshift.io/contai...=\n openshift.io/generated-by=OpenShiftNewApp\nContainers:\n demo:\n Image: docker-registry.default.svc:5000/test/demo@sha256:0a9f2487a0d95d51511e49d20dc9ff6f350436f935966b0c83cb98a7a8c381a\n Port: 8080/TCP\n Volume Mounts:\n /opt/app-root/src/uploaded from persistent-volume (rw)\n```\nEnvironment Variables: <none>\nVolumes:\npersistent-volume:\n Type: PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)\n *ClaimName: filestore*\n ReadOnly: false\n...omitted...\n\n3. Now that the deployment configuration uses the new **pvc**, run **oc rsync** to place the files onto the new **pvc**:\n\n```\n$ oc rsync uploaded demo-3-2b8gs:/opt/app-root/src/\nsending incremental file list\nuploaded/\nuploaded/ocp_sop.txt\nuploaded/lost+found/\n\nsent 181 bytes received 39 bytes 146.67 bytes/sec\ntotal size is 32 speedup is 0.15\n```\n\n4. Validate that the file is back on the pod by using **oc rsh** to connect to the pod and view the contents of the directory:\n\n```\n$ oc rsh demo-3-2b8gs\nsh-4.2$ ls /opt/app-root/src/uploaded/\nlost+found ocp_sop.txt\n```\n\n### 6.2.3. Pruning images and containers\n\nSee the **Pruning Resources** topic for information about pruning collected data and older versions of objects.\nCHAPTER 7. DOCKER TASKS\n\nOpenShift Container Platform uses Docker to run applications in pods that are composed by any number of containers.\n\nAs a cluster administrator, sometimes Docker requires some extra configuration in order to efficiently run elements of the OpenShift Container Platform installation.\n\n7.1. INCREASING DOCKER STORAGE\n\nIncreasing the amount of storage available ensures continued deployment without any outages. To do so, a free partition must be made available that contains an appropriate amount of free capacity.\n\n7.1.1. Evacuating the node\n\nProcedure\n\n1. From a master instance, or as a cluster administrator, allow the evacuation of any pod from the node and disable scheduling of other pods on that node:\n\n ```bash\n $ NODE=ose-app-node01.example.com\n $ oc adm manage-node $NODE --schedulable=false\n NAME STATUS AGE VERSION\n ose-app-node01.example.com Ready,SchedulingDisabled 20m v1.6.1+5115d708d7\n \n $ oc adm drain $NODE --ignore-daemonsets\n node \"ose-app-node01.example.com\" already cordoned\n pod \"perl-1-build\" evicted\n pod \"perl-1-3lnsh\" evicted\n pod \"perl-1-9jzd8\" evicted\n node \"ose-app-node01.example.com\" drained\n \n NOTE\n If there are containers running with local volumes that will not migrate, run the following command: `oc adm drain $NODE --ignore-daemonsets --delete-local-data`.\n \n 2. List the pods on the node to verify that they have been removed:\n\n ```bash\n $ oc adm manage-node $NODE --list-pods\n Listing matched pods on node: ose-app-node01.example.com\n NAME READY STATUS RESTARTS AGE\n \n For more information on evacuating and draining pods or nodes, see Node maintenance.\n\n7.1.2. Increasing storage\n\nYou can increase Docker storage in two ways: attaching a new disk, or extending the existing disk.\n\nIncreasing storage with a new disk\nPrerequisites\n\n- A new disk must be available to the existing instance that requires more storage. In the following steps, the original disk is labeled `/dev/xvdb`, and the new disk is labeled `/dev/xvdd`, as shown in the `/etc/sysconfig/docker-storage-setup` file:\n\n ```\n # vi /etc/sysconfig/docker-storage-setup\n DEVS=\"/dev/xvdb /dev/xvdd\"\n ```\n\n**NOTE**\n\nThe process may differ depending on the underlying OpenShift Container Platform infrastructure.\n\nProcedure\n\n1. Stop the `docker` and `atomic-openshift-node` services:\n\n ```\n # systemctl stop docker atomic-openshift-node\n ```\n\n2. Run the `docker-storage-setup` command to extend the volume groups and logical volumes associated with container storage:\n\n ```\n # docker-storage-setup\n INFO: Volume group backing root filesystem could not be determined\n INFO: Device /dev/xvdb is already partitioned and is part of volume group docker_vol\n INFO: Device node /dev/xvdd1 exists.\n Physical volume \"/dev/xvdd1\" successfully created.\n Volume group \"docker_vol\" successfully extended\n ```\n\n3. Start the Docker services:\n\n ```\n # systemctl start docker\n # vgs\n VG #PV #LV #SN Attr VSize VFree\n docker_vol 2 1 0 wz--n- 64.99g <55.00g\n ```\n\n4. A benefit in adding a disk compared to creating a new volume group and re-running `docker-storage-setup` is that the images that were used on the system still exist after the new storage has been added:\n\n ```\n # docker images\n REPOSITORY TAG IMAGE ID CREATED\n SIZE\n docker-registry.default.svc:5000/tet/perl latest 8b0b0106fb5e 13 minutes ago 627.4 MB\n registry.access.redhat.com/rhscl/perl-524-rhel7 <none> 912b01ac7570 6 days ago 559.5 MB\n registry.access.redhat.com/openshift3/ose-deployer v3.6.173.0.21 89fd398a337d 5 weeks ago 970.2 MB\n registry.access.redhat.com/openshift3/ose-sti-builder v3.6.173.0.21 99ab8895d88a 5 weeks ago 970.2 MB\n registry.access.redhat.com/openshift3/ose-pod v3.6.173.0.21 63accd48a0d7 5 weeks ago 208.6 MB\n ```\n5. With the increase in storage capacity, enable the node to be schedulable in order to accept new incoming pods.\n As a cluster administrator, run the following from a master instance:\n\n```\n$ oc adm manage-node ${NODE} --schedulable=true\n```\n\n<table>\n<thead>\n<tr>\n<th>Node Name</th>\n<th>Status</th>\n<th>Age</th>\n<th>OS Version</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ose-master01.example.com</td>\n<td>Ready, SchedulingDisabled</td>\n<td>24m</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ose-master02.example.com</td>\n<td>Ready, SchedulingDisabled</td>\n<td>24m</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ose-master03.example.com</td>\n<td>Ready, SchedulingDisabled</td>\n<td>24m</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ose-infra-node01.example.com</td>\n<td>Ready</td>\n<td>24m</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ose-infra-node02.example.com</td>\n<td>Ready</td>\n<td>24m</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ose-infra-node03.example.com</td>\n<td>Ready</td>\n<td>24m</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ose-app-node01.example.com</td>\n<td>Ready</td>\n<td>24m</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n<tr>\n<td>ose-app-node02.example.com</td>\n<td>Ready</td>\n<td>24m</td>\n<td>v1.6.1+5115d708d7</td>\n</tr>\n</tbody>\n</table>\n\nIncreasing storage with a new disk\n\n1. Evacuate the node following the previous steps.\n\n2. Stop the `docker` and `atomic-openshift-node` services:\n\n```\n# systemctl stop docker atomic-openshift-node\n```\n\n3. Resize the existing disk as desired. This can can depend on your environment:\n - If you are using LVM (Logical Volume Manager):\n - Remove the logical volume:\n ```\n # lvremove /dev/docker_vg/docker/lv\n ```\n - Remove the Docker volume group:\n ```\n # vgremove docker_vg\n ```\n - Remove the physical volume:\n ```\n # pvremove /dev/<my_previous_disk_device>\n ```\n - If you are using a cloud provider, you can detach the disk, destroy the disk, then create a new bigger disk, and attach it to the instance.\n - For a non-cloud environment, the disk and file system can be resized. See the following solution for more information:\n - [https://access.redhat.com/solutions/199573](https://access.redhat.com/solutions/199573)\n\n4. Verify that the `/etc/sysconfig/container-storage-setup` file is correctly configured for the new disk by checking the device name, size, etc.\n\n5. Run `docker-storage-setup` to reconfigure the new disk:\n\n```\n# docker-storage-setup\n```\n\nINFO: Volume group backing root filesystem could not be determined\nINFO: Device /dev/xvdb is already partitioned and is part of volume group docker_vol\nINFO: Device node /dev/xvdd1 exists.\nPhysical volume \"/dev/xvdd1\" successfully created.\nVolume group \"docker_vol\" successfully extended\n\n6. Start the Docker services:\n\n```bash\n# systemctl start docker\n# vgs\nVG #PV #LV #SN Attr VSize VFree\ndocker_vol 2 1 0 wz--n- 64.99G <55.0G\n```\n\n7. Start the `atomic-openshift-node` service:\n\n```bash\n# systemctl start atomic-openshift-node\n```\n\n### 7.1.3. Changing the storage backend\n\nWith the advancements of services and file systems, changes in a storage backend may be necessary to take advantage of new features. The following steps provide an example of changing a device mapper backend to an `overlay2` storage backend. `overlay2` offers increased speed and density over traditional device mapper.\n\n#### 7.1.3.1. Evacuating the node\n\n1. From a master instance, or as a cluster administrator, allow the evacuation of any pod from the node and disable scheduling of other pods on that node:\n\n ```bash\n $ NODE=ose-app-node01.example.com\n $ oc adm manage-node ${NODE} --schedulable=false\n NAME STATUS AGE VERSION\n ose-app-node01.example.com Ready,SchedulingDisabled 20m v1.6.1+5115d708d7\n $ oc adm drain ${NODE} --ignore-daemonsets\n node \"ose-app-node01.example.com\" already cordoned\n pod \"perl-1-build\" evicted\n pod \"perl-1-3lnsh\" evicted\n pod \"perl-1-9jzd8\" evicted\n node \"ose-app-node01.example.com\" drained\n ```\n\n **NOTE**\n \n If there are containers running with local volumes that will not migrate, run the following command: `oc adm drain ${NODE} --ignore-daemonsets --delete-local-data`\n\n2. List the pods on the node to verify that they have been removed:\n\n ```bash\n $ oc adm manage-node ${NODE} --list-pods\n Listing matched pods on node: ose-app-node01.example.com\n NAME READY STATUS RESTARTS AGE\n ```\nFor more information on evacuating and draining pods or nodes, see Node maintenance.\n\n3. With no containers currently running on the instance, stop the **docker** and **atomic-openshift-node service** services:\n\n ```\n # systemctl stop docker atomic-openshift-node\n ```\n\n4. Verify the name of the volume group, logical volume name, and physical volume name:\n\n ```\n # vgs\n VG #PV #LV #SN Attr VSize VFree\n docker_vol 1 1 0 wz--n- <25.00g 15.00g\n \n # lvs\n LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert\n dockerlv docker_vol -wi-ao---- <10.00g\n \n # lvremove /dev/docker_vol/docker-pool -y\n # vgremove docker_vol -y\n # pvs\n PV VG Fmt Attr PSize PFree\n /dev/xvdb1 docker_vol lvm2 a-- <25.00g 15.00g\n \n # pvremove /dev/xvdb1 -y\n # rm -Rf /var/lib/docker/*\n # rm -f /etc/sysconfig/docker-storage\n ```\n\n5. Modify the **docker-storage-setup** file to specify the **STORAGE_DRIVER**.\n\n **NOTE**\n\n When a system is upgraded from Red Hat Enterprise Linux version 7.3 to 7.4, the **docker** service attempts to use **/var** with the **STORAGE_DRIVER** of extfs. The use of extfs as the **STORAGE_DRIVER** causes errors. See the following bug for more info regarding the error:\n\n - Bugzilla ID: 1490910\n\n ```\n DEVS=/dev/xvdb\n VG=docker_vol\n DATA_SIZE=95%VG\n STORAGE_DRIVER=overlay2\n CONTAINER_ROOT_LV_NAME=dockerlv\n CONTAINER_ROOT_LV_MOUNT_PATH=/var/lib/docker\n CONTAINER_ROOT_LV_SIZE=100%FREE\n ```\n\n6. Set up the storage:\n\n ```\n # docker-storage-setup\n ```\n\n7. Start the **docker** and **atomic-openshift-node** services:\n\n ```\n # systemctl start docker atomic-openshift-node\n ```\n8. With the storage modified to use overlay2, enable the node to be schedulable in order to accept new incoming pods.\n From a master instance, or as a cluster administrator:\n\n```\n$ oc adm manage-node $(NODE) --schedulable=true\n```\n\n```\nose-master01.example.com Ready,SchedulingDisabled 24m v1.6.1+5115d708d7\nose-master02.example.com Ready,SchedulingDisabled 24m v1.6.1+5115d708d7\nose-master03.example.com Ready,SchedulingDisabled 24m v1.6.1+5115d708d7\nose-infra-node01.example.com Ready 24m v1.6.1+5115d708d7\nose-infra-node02.example.com Ready 24m v1.6.1+5115d708d7\nose-infra-node03.example.com Ready 24m v1.6.1+5115d708d7\nose-app-node01.example.com Ready 24m v1.6.1+5115d708d7\nose-app-node02.example.com Ready 24m v1.6.1+5115d708d7\n```\n\n### 7.2. MANAGING DOCKER CERTIFICATES\n\nAn OpenShift Container Platform internal registry is created as a pod. However, containers may be pulled from external registries if desired. By default, registries listen on TCP port 5000. Registries provide the option of securing exposed images via TLS or running a registry without encrypting traffic.\n\n**WARNING**\n\nDocker interprets .crt files as CA certificates and .cert files as client certificates. Any CA extensions must be .crt.\n\n#### 7.2.1. Installing a certificate authority certificate for external registries\n\nIn order to use OpenShift Container Platform with an external registry, the registry certificate authority (CA) certificate must be trusted for all the nodes that can pull images from the registry.\n\n**NOTE**\n\nDepending on the Docker version, the process to trust a Docker registry varies. The latest versions of Docker’s root certificate authorities are merged with system defaults. Prior to docker version 1.13, the system default certificate is used only when no other custom root certificates exist.\n\n**Procedure**\n\n1. Copy the CA certificate to /etc/pki/ca-trust/source/anchors/:\n ```\n $ sudo cp myregistry.example.com.crt /etc/pki/ca-trust/source/anchors/\n ```\n\n2. Extract and add the CA certificate to the list of trusted certificates authorities:\n ```\n $ sudo update-ca-trust extract\n ```\n3. Verify the SSL certificate using the `openssl` command:\n\n```\n$ openssl verify myregistry.example.com.crt\nmyregistry.example.com.crt: OK\n```\n\n4. Once the certificate is in place and the trust is updated, restart the `docker` service to ensure the new certificates are properly set:\n\n```\n$ sudo systemctl restart docker.service\n```\n\nFor Docker versions prior to 1.13, perform the following additional steps for trusting certificates of authority:\n\n1. On every node create a new directory in `/etc/docker/certs.d` where the name of the directory is the host name of the Docker registry:\n\n ```\n $ sudo mkdir -p /etc/docker/certs.d/myregistry.example.com\n ```\n\n **NOTE**\n \n The port number is not required unless the Docker registry cannot be accessed without a port number. Addressing the port to the original Docker registry is as follows: `myregistry.example.com:port`\n\n2. Accessing the Docker registry via IP address requires the creation of a new directory within `/etc/docker/certs.d` on every node where the name of the directory is the IP of the Docker registry:\n\n ```\n $ sudo mkdir -p /etc/docker/certs.d/10.10.10.10\n ```\n\n3. Copy the CA certificate to the newly created Docker directories from the previous steps:\n\n ```\n $ sudo cp myregistry.example.com.crt \\\n /etc/docker/certs.d/myregistry.example.com/ca.crt\n $ sudo cp myregistry.example.com.crt /etc/docker/certs.d/10.10.10.10/ca.crt\n ```\n\n4. Once the certificates have been copied, restart the `docker` service to ensure the new certificates are used:\n\n ```\n $ sudo systemctl restart docker.service\n ```\n\n### 7.2.2. Docker certificates backup\n\nWhen performing a node host backup, ensure to include the certificates for external registries.\n\n**Procedure**\n\n1. If using `/etc/docker/certs.d`, copy all the certificates included in the directory and store the files:\n\n ```\n $ sudo tar -czvf docker-registry-certs-$(hostname)-$(date +%Y%m%d).tar.gz /etc/docker/certs.d/\n ```\n2. If using a system trust, store the certificates prior to adding them within the system trust. Once the store is complete, extract the certificate for restoration using the `trust` command. Identify the system trust CAs and note the `pkcs11` ID:\n\n ```bash\n $ trust list\n ...\n pkcs11:id=%a5%b3%e1%2b%2b%49%b6%d7%73%a1%aa%94%f5%01%e7%73%65%4c%ac%50;type=cert\n type: certificate\n label: MyCA\n trust: anchor\n category: authority\n ...\n ```\n\n3. Extract the certificate in `pem` format and provide it a name. For example, `myca.crt`.\n\n ```bash\n $ trust extract --format=pem-bundle --filter=\"%a5%b3%e1%2b%2b%49%b6%d7%73%a1%aa%94%f5%01%e7%73%65%4c%ac%50;type=cert\" myca.crt\n ```\n\n4. Verify the certificate has been properly extracted via `openssl`:\n\n ```bash\n $ openssl verify myca.crt\n ```\n\n5. Repeat the procedure for all the required certificates and store the files in a remote location.\n\n### 7.2.3. Docker certificates restore\n\nIn the event of the deletion or corruption of the Docker certificates for the external registries, the restore mechanism uses the same steps as the installation method using the files from the backups performed previously.\n\n### 7.3. MANAGING DOCKER REGISTRIES\n\nYou can configure OpenShift Container Platform to use external `docker` registries to pull images. However, you can use configuration files to allow or deny certain images or registries.\n\nIf the external registry is exposed using certificates for the network traffic, it can be named as a secure registry. Otherwise, traffic between the registry and host is plain text and not encrypted, meaning it is an insecure registry.\n\n#### 7.3.1. Docker search external registries\n\nBy default, the `docker` daemon has the ability to pull images from any registry, but the search operation is performed against `docker.io/` and `registry.access.redhat.com`. The daemon can be configured to search images from other registries using the `--add-registry` option with the `docker` daemon.\n\n**NOTE**\n\nThe ability to search images from the Red Hat Registry `registry.access.redhat.com` exists by default in the Red Hat Enterprise Linux `docker` package.\nProcedure\n\n1. To allow users to search for images using `docker search` with other registries, add those registries to the `/etc/containers/registries.conf` file under the `registries` parameter:\n\n```\nregistries:\n - registry.access.redhat.com\n - my.registry.example.com\n```\n\nPrior to OpenShift Container Platform version 3.6, this was accomplished using `/etc/sysconfig/docker` with the following options:\n\n```\nADD_REGISTRY=\"--add-registry=registry.access.redhat.com --add-registry=my.registry.example.com\"\n```\n\nThe first registry added is the first registry searched.\n\n2. Restart the `docker` daemon to allow for `my.registry.example.com` to be used:\n\n```\n$ sudo systemctl restart docker.service\n```\n\nRestarting the `docker` daemon causes the `docker` containers to restart.\n\n3. Using the Ansible installer, this can be configured using the `openshift_docker_additional_registries` variable in the Ansible hosts file:\n\n```\nopenshift_docker_additional_registries=registry.access.redhat.com,my.registry.example.com\n```\n\n### 7.3.2. Docker external registries whitelist and blacklist\n\nDocker can be configured to block operations from external registries by configuring the `registries` and `block_registries` flags for the `docker` daemon.\n\n**Procedure**\n\n1. Add the allowed registries to the `/etc/containers/registries.conf` file with the `registries` flag:\n\n```\nregistries:\n - registry.access.redhat.com\n - my.registry.example.com\n```\n\nPrior to 3.6, the `/etc/sysconfig/docker` file is modified instead:\n\n```\nADD_REGISTRY=\"--add-registry=registry.access.redhat.com --add-registry=my.registry.example.com\"\n```\n\n**NOTE**\n\nThe `docker.io` registry can be added using the same method.\n\n2. Block the rest of the registries:\n3. Block the rest of the registries in older versions:\n\n```\nBLOCK_REGISTRY='--block-registry=all'\n```\n\n4. Restart the **docker** daemon:\n\n```\n$ sudo systemctl restart docker.service\n```\n\nRestarting the **docker** daemon causes the **docker** containers to restart.\n\n5. In this example, the **docker.io** registry has been blacklisted, so any operation regarding that registry fails:\n\n```\n$ sudo docker pull hello-world\nUsing default tag: latest\nTrying to pull repository registry.access.redhat.com/hello-world ...\nTrying to pull repository my.registry.example.com/hello-world ...\nunknown: Not Found\n$ sudo docker pull docker.io/hello-world\nUsing default tag: latest\nTrying to pull repository docker.io/library/hello-world ...\nAll endpoints blocked.\n```\n\nAdd **docker.io** back to the **registries** variable by modifying the file again and restarting the service.\n\n```\nregistries:\n - registry.access.redhat.com\n - my.registry.example.com\n - docker.io\nblock_registries:\n - all\n```\n\nor\n\n```\nADD_REGISTRY=\"--add-registry=registry.access.redhat.com --add-registry=my.registry.example.com --add-registry=docker.io\"\nBLOCK_REGISTRY='--block-registry=all'\n```\n\n6. Restart the Docker service:\n\n```\n$ sudo systemctl restart docker\n```\n\n7. To verify that the image is now available to be pulled:\n\n```\n$ sudo docker pull docker.io/hello-world\nUsing default tag: latest\nTrying to pull repository docker.io/library/hello-world ...\nlatest: Pulling from docker.io/library/hello-world\n```\n8. If using an external registry is required, for example to modify the docker daemon configuration file in all the node hosts that require to use that registry, create a blacklist on those nodes to avoid malicious containers from being executed.\n\nUsing the Ansible installer, this can be configured using the openshift_docker_additional_registries and openshift_docker_blocked_registries variables in the Ansible hosts file:\n\n```plaintext\nopenshift_docker_additional_registries=registry.access.redhat.com,my.registry.example.com\nopenshift_docker_blocked_registries=all\n```\n\n### 7.3.3. Secure registries\n\nIn order to be able to pull images from an external registry, it is required to trust the registry certificates, otherwise the pull image operation fails.\n\nIn order to do so, see the Installing a Certificate Authority Certificate for External Registries section.\n\nIf using a whitelist, the external registries should be added to the registries variable, as explained above.\n\n### 7.3.4. Insecure registries\n\nExternal registries that use non-trusted certificates, or without certificates at all, should be avoided.\n\nHowever, any insecure registries should be added using the --insecure-registry option to allow for the docker daemon to pull images from the repository. This is the same as the --add-registry option, but the docker operation is not verified.\n\nThe registry should be added using both options to enable search, and, if there is a blacklist, to perform other operations, such as pulling images.\n\nFor testing purposes, an example is shown on how to add a localhost insecure registry.\n\n**Procedure**\n\n1. Modify `/etc/containers/registries.conf` configuration file to add the localhost insecure registry:\n\n```plaintext\nregistries:\n - registry.access.redhat.com\n - my.registry.example.com\n - docker.io\ninsecure_registries:\n - localhost:5000\nblock_registries:\n - all\n```\n\nPrior to 3.6, modify the `/etc/sysconfig/docker` configuration file to add the localhost:\n\n```plaintext\nADD_REGISTRY=\"--add-registry=registry.access.redhat.com --add-registry=my.registry.example.com --add-registry=docker.io --add-registry=localhost:5000\"\nINSECURE_REGISTRY=\"--insecure-registry=localhost:5000\"\n```\n2. Restart the `docker` daemon to use the registry:\n ```bash\n $ sudo systemctl restart docker.service\n ```\n Restarting the `docker` daemon causes the `docker` containers to be restarted.\n\n3. Run a Docker registry pod at `localhost`:\n ```bash\n $ sudo docker run -p 5000:5000 registry:2\n ```\n\n4. Pull an image:\n ```bash\n $ sudo docker pull openshift/hello-openshift\n ```\n\n5. Tag the image:\n ```bash\n $ sudo docker tag docker.io/openshift/hello-openshift:latest localhost:5000/hello-openshift-local:latest\n ```\n\n6. Push the image to the local registry:\n ```bash\n $ sudo docker push localhost:5000/hello-openshift-local:latest\n ```\n\n7. Using the Ansible installer, this can be configured using the `openshift_docker_additional_registries`, `openshift_docker_blocked_registries`, and `openshift_docker_insecure_registries` variables in the `Ansible` hosts file:\n ```\n openshift_docker_additional_registries=registry.access.redhat.com,my.registry.example.com,localhost:5000\n openshift_docker_insecure_registries=localhost:5000\n openshift_docker_blocked_registries=all\n ```\n\n **NOTE**\n You can also set the `openshift_docker_insecure_registries` variable to the IP address of the host. `0.0.0.0/0` is not a valid setting.\n\n### 7.3.5. Authenticated registries\n\nUsing authenticated registries with `docker` requires the `docker` daemon to log in to the registry. With OpenShift Container Platform, a different set of steps must be performed, because the users can not run `docker login` commands on the host. Authenticated registries can be used to limit the images users can pull or who can access the external registries.\n\nIf an external `docker` registry requires authentication, create a special secret in the project that uses that registry and then use that secret to perform the `docker` operations.\n\n**Procedure**\n\n1. Create a `dockercfg` secret in the project where the user is going to log in to the `docker` registry:\n2. If a `.dockercfg` file exists, create the secret using the `oc` command:\n\n```bash\n$ oc create secret generic <my_registry> --from-file=.dockercfg=<path/to/.dockercfg> --\ntype=kubernetes.io/dockercfg\n```\n\n3. Populate the `$HOME/.docker/config.json` file:\n\n```bash\n$ oc create secret generic <my_registry> --from-file=.dockerconfigjson=<path/to/.dockercfg> --\ntype=kubernetes.io/dockerconfigjson\n```\n\n4. Use the `dockercfg` secret to pull images from the authenticated registry by linking the secret to\nthe service account performing the pull operations. The default service account to pull images is named `default`:\n\n```bash\n$ oc secrets link default <my_registry> --for=pull\n```\n\n5. For pushing images using the S2I feature, the `dockercfg` secret is mounted in the S2I pod, so it\nneeds to be linked to the proper service account that performs the build. The default service\naccount used to build images is named `builder`.\n\n```bash\n$ oc secrets link builder <my_registry>\n```\n\n6. In the `buildconfig`, the secret should be specified for push or pull operations:\n\n```\n\"type\": \"Source\",\n\"sourceStrategy\": {\n \"from\": {\n \"kind\": \"DockerImage\",\n \"name\": \"my.registry.example.com/myproject/myimage:stable\"\n },\n \"pullSecret\": {\n \"name\": \"mydockerregistry\"\n }\n},\n...\n```\n\n7. If the external registry delegates authentication to external services, create both `dockercfg`\nsecrets: the registry one using the registry URL and the external authentication system using its\nown URL. Both secrets should be added to the service accounts.\n$ oc project <my_project>\n$ oc create secret docker-registry <my_registry> --docker-server=*<my_registry_example.com> --docker-username=<username> --docker-password=<my_password> --docker-email=<me@example.com>\n$ oc create secret docker-registry <my_docker_registry_ext_auth> --docker-server=<my.authsystem.example.com> --docker-username=<username> --docker-password=<my_password> --docker-email=<me@example.com>\n$ oc secrets link default <my_registry> --for=pull\n$ oc secrets link default <my_docker_registry_ext_auth> --for=pull\n$ oc secrets link builder <my_registry>\n$ oc secrets link builder <my_docker_registry_ext_auth>\n\n7.3.6. ImagePolicy admission plug-in\n\nAn admission control plug-in intercepts requests to the API, and performs checks depending on the configured rules and allows or denies certain actions based on those rules. OpenShift Container Platform can limit the allowed images running in the environment using the ImagePolicy admission plug-in where it can control:\n\n- The source of images: which registries can be used to pull images\n- Image resolution: force pods to run with immutable digests to ensure the image does not change due to a re-tag\n- Container image label restrictions: force an image to have or not have particular labels\n- Image annotation restrictions: force an image in the integrated container registry to have or not have particular annotations\n\n**WARNING**\n\nImagePolicy admission plug-in is currently considered beta.\n\nProcedure\n\n1. If the ImagePolicy plug-in is enabled, it needs to be modified to allow the external registries to be used by modifying the /etc/origin/master/master-config.yaml file on every master node:\n\n```yaml\nadmissionConfig:\n pluginConfig:\n openshift.io/ImagePolicy:\n configuration:\n kind: ImagePolicyConfig\n apiVersion: v1\n executionRules:\n - name: allow-images-from-other-registries\n onResources:\n - resource: pods\n - resource: builds\n matchRegistries:\n```\nNOTE\n\nEnabling `ImagePolicy` requires users to specify the registry when deploying an application like `oc new-app docker.io/kubernetes/guestbook` instead of `oc new-app kubernetes/guestbook`, otherwise it fails.\n\n2. To enable the admission plug-ins at installation time, the `openshift_master_admission_plugin_config` variable can be used with a JSON formatted string including all the `pluginConfig` configuration:\n\n```yaml\nopenshift_master_admission_plugin_config=\"openshift.io/ImagePolicy\":{\"configuration\":\n {\n \"kind\": \"ImagePolicyConfig\",\n \"apiVersion\": \"v1\",\n \"executionRules\": [{\n \"name\": \"allow-images-from-other-registries\",\n \"onResources\": [{\n \"resource\": \"pods\"}, {\n \"resource\": \"builds\"}],\n \"matchRegistries\": [\n \"docker.io\",\n \"my.registry.example.com\",\n \"registry.access.redhat.com\"]}\n ]}\n}\n```\n\nWARNING\n\nThere is a current issue to be fixed in OpenShift Container Platform 3.6.1 where `ImagePolicy` pods can not be deployed using default templates, and give the following error message `Failed create | Error creating: Pod \"\" is invalid: spec.containers[0].image: Forbidden: this image is prohibited by policy.`\n\nSee the [Image Policy is not working as expected](https://access.redhat.com/solutions/1187478) Red Hat Knowledgebase article for a workaround.\n\n### 7.3.7. Import images from external registries\n\nApplication developers can import images to create `imagestreams` using the `oc import-image` command, and OpenShift Container Platform can be configured to allow or deny image imports from external registries.\n\n**Procedure**\n\n1. To configure the allowed registries where users can import images, add the following to the `/etc/origin/master/master-config.yaml` file:\n\n```yaml\nimagePolicyConfig:\n allowedRegistriesForImport:\n - domainName: docker.io\n - domainName: '*.docker.io'\n - domainName: '*.redhat.com'\n - domainName: 'my.registry.example.com'\n```\n2. To import images from an external authenticated registry, create a secret within the desired project.\n\n3. Even if not recommended, if the external authenticated registry is insecure or the certificates cannot be trusted, the `oc import-image` command can be used with the `--insecure=true` option.\n \n If the external authenticated registry is secure, the registry certificate should be trusted in the master hosts as they run the registry import controller as:\n \n Copy the certificate in the `/etc/pki/ca-trust/source/anchors/`:\n \n ```bash\n $ sudo cp <my.registry.example.com.crt> /etc/pki/ca-trust/source/anchors/<my.registry.example.com.crt>\n ```\n \n 4. Run `update-ca-trust` command:\n \n ```bash\n $ sudo update-ca-trust\n ```\n \n 5. Restart the master services on all the master hosts:\n \n ```bash\n $ sudo systemctl restart atomic-openshift-master-api\n $ sudo systemctl restart atomic-openshift-master-controllers\n ```\n \n 6. The certificate for the external registry should be trusted in the OpenShift Container Platform registry:\n \n ```bash\n $ for i in pem openssl java; do\n oc create configmap ca-trust-extracted-${i} --from-file /etc/pki/ca-trust/extracted/${i}\n oc set volume dc/docker-registry --add -m /etc/pki/ca-trust/extracted/${i} --configmap-name=ca-trust-extracted-${i} --name ca-trust-extracted-${i}\n done\n ```\n \n **WARNING**\n \n There is no official procedure currently for adding the certificate to the registry pod, but the above workaround can be used.\n \n This workaround creates configmaps with all the trusted certificates from the system running those commands, so the recommendation is to run it from a clean system where just the required certificates are trusted.\n \n 7. Alternatively, modify the registry image in order to trust the proper certificates rebuilding the image using a **Dockerfile** as:\n \n ```bash\n FROM registry.access.redhat.com/openshift3/ose-docker-registry:v3.6\n ADD <my.registry.example.com.crt> /etc/pki/ca-trust/source/anchors/ \n USER 0\n RUN update-ca-trust extract\n USER 1001\n ```\n8. Rebuild the image, push it to a **docker** registry, and use that image as `spec.template.spec.containers[\"name\":\"registry\"].image` in the registry deploymentconfig:\n\n $ oc patch dc docker-registry -p '{\"spec\":{\"template\":{\"spec\":{\"containers\": [{\"name\":\"registry\",\"image\":\"*myregistry.example.com/openshift3/ose-docker-registry:latest*\"}]}}}}'\n\n**NOTE**\n\nTo add the `imagePolicyConfig` configuration at installation, the `openshift_master_image_policy_config` variable can be used with a `json` formatted string including all the `imagePolicyConfig` configuration, like:\n\n ```\n openshift_master_image_policy_config=\"imagePolicyConfig\": {\n \"allowedRegistriesForImport\": [{\"domainName\": \"docker.io\"}],\n [{\"domainName\": \"\\.docker.io\"}],\n [{\"domainName\": \"\\*.redhat.com\"}],\n [{\"domainName\": \"*my.registry.example.com*\"}]\n }\n ```\n\nFor more information about the **ImagePolicy**, see the **ImagePolicy** admission plug-in section.\n\n### 7.3.8. OpenShift Container Platform registry integration\n\nYou can install OpenShift Container Platform as a stand-alone container registry to provide only the registry capabilities, but with the advantages of running in an OpenShift Container Platform platform.\n\nFor more information about the OpenShift Container Platform registry, see [Installing a Stand-alone Deployment of OpenShift Container Registry](#).\n\nTo integrate the OpenShift Container Platform registry, all previous sections apply. From the OpenShift Container Platform point of view, it is treated as an external registry, but there are some extra tasks that need to be performed, because it is a multi-tenant registry and the authorization model from OpenShift Container Platform applies so when a new project is created, the registry does not create a project within its environment as it is independent.\n\n#### 7.3.8.1. Connect the registry project with the cluster\n\nAs the registry is a full OpenShift Container Platform environment with a registry pod and a web interface, the process to create a new project in the registry is performed using the `oc new-project` or `oc create` command line or via the web interface.\n\nOnce the project has been created, the usual service accounts (**builder**, **default**, and **deployer**) are created automatically, as well as the project administrator user is granted permissions. Different users can be authorized to push/pull images as well as \"anonymous\" users.\n\nThere can be several use cases, such as allowing all the users to pull images from this new project within the registry, but if you want to have a 1:1 project relationship between OpenShift Container Platform and the registry, where the users can push and pull images from that specific project, some steps are required.\nWARNING\n\nThe registry web console shows a token to be used for pull/push operations, but\nthe token showed there is a session token, so it expires. Creating a service account\nwith specific permissions allows the administrator to limit the permissions for the\nservice account, so that, for example, different service accounts can be used for\npush or pull images. Then, a user does not have to configure for token expiration,\nsecret recreation, and other tasks, as the service account tokens will not expire.\n\nProcedure\n\n1. Create a new project:\n\n $ oc new-project <my_project>\n\n2. Create a registry project:\n\n $ oc new-project <registry_project>\n\n3. Create a service account in the registry project:\n\n $ oc create serviceaccount <my_serviceaccount> -n <registry_project>\n\n4. Give permissions to push and pull images using the `registry-editor` role:\n\n $ oc adm policy add-role-to-user registry-editor -z <my_serviceaccount> -n <registry_project>\n\n If only pull permissions are required, the `registry-viewer` role can be used.\n\n5. Get the service account token:\n\n $ TOKEN=$(oc sa get-token <my_serviceaccount> -n <registry_project>)\n\n6. Use the token as the password to create a `dockercfg` secret:\n\n $ oc create secret docker-registry <my_registry> \\\n --docker-server=<myregistry.example.com> --docker-username=<notused> --docker-\n password=${TOKEN} --docker-email=<me@example.com>\n\n7. Use the `dockercfg` secret to pull images from the registry by linking the secret to the service\naccount performing the pull operations. The default service account to pull images is named\ndefault:\n\n $ oc secrets link default <my_registry> --for=pull\n\n8. For pushing images using the S2I feature, the `dockercfg` secret is mounted in the S2I pod, so it\nneeds to be linked to the proper service account that performs the build. The default service\naccount used to build images is named `builder`:\n$ oc secrets link builder <my_registry>\n\n9. In the **buildconfig**, the secret should be specified for push or pull operations:\n\n```json\n\"type\": \"Source\",\n\"sourceStrategy\": {\n \"from\": {\n \"kind\": \"DockerImage\",\n \"name\": \"<myregistry.example.com/registry_project/my_image:stable>\"\n },\n \"pullSecret\": {\n \"name\": \"<my_registry>\"\n }\n},\n\n...[OUTPUT ABBREVIATED]...\n\n\"output\": {\n \"to\": {\n \"kind\": \"DockerImage\",\n \"name\": \"<myregistry.example.com/registry_project/my_image:latest>\"\n },\n \"pushSecret\": {\n \"name\": \"<my_registry>\"\n }\n}\n\n...[OUTPUT ABBREVIATED]...\n```\nCHAPTER 8. MANAGING CERTIFICATES\n\nOver the lifetime of a OpenShift Container Platform cluster, certificates will enter various phases of their lifecycle. The following procedures describe how to manage various parts of that lifecycle.\n\n8.1. CHANGING AN APPLICATION’S SELF-SIGNED CERTIFICATE TO CA-SIGNED CERTIFICATE\n\nSome application templates create a self-signed certificate that is then directly presented by the application to clients. As an example, by default and as part of the OpenShift Container Platform Ansible installer deployment process, the metrics deployer creates self-signed certificates.\n\nThese self-signed certificates are not recognized by browsers. To mitigate this issue, use a publicly signed certificate, then configure it to re-encrypt traffic with the self-signed certificate.\n\n1. Delete the existing route:\n\n\n```\n$ oc delete route hawkular-metrics -n openshiftinfra\n```\n\nWith the route deleted, the certificates that will be used in the new route with the re-encrypt strategy must be assembled from the existing wildcard and self-signed certificates created by the metrics deployer. The following certificates must be available:\n\n- Wildcard CA certificate\n- Wildcard private key\n- Wildcard certificate\n- Hawkular CA certificate\n\nEach certificate must be available as a file on the file system for the new route.\n\nYou can retrieve the Hawkular CA and store it in a file by executing the following command:\n\n\n```\n$ oc get secrets hawkular-metrics-certificate -n openshiftinfra -o jsonpath='{.data.hawkular-metrics-ca\\[\\].certificate}' | base64 -d > hawkular-internal-ca.crt\n```\n\n2. Locate the wildcard private key, certificate, and CA certificate. Place each into a separate file, such as `wildcard.key`, `wildcard.crt`, and `wildcard.ca`.\n\n3. Create the new re-encrypt route:\n\n\n```\n$ oc create route reencrypt hawkular-metrics-reencrypt -n openshiftinfra -o jsonpath='{.spec.host}' | base64 -d > reencrypt.crt\n```\n\n```\n$ oc get secrets hawkular-metrics-certificate -n openshiftinfra -o jsonpath='{.data.hawkular-metrics-ca\\[\\].certificate}' | base64 -d > hawkular-internal-ca.crt\n```\n\n```\n$ oc create route reencrypt hawkular-metrics-reencrypt -n openshiftinfra -o jsonpath='{.spec.host}' | base64 -d > reencrypt.crt\n```\n\n```\n$ oc get secrets hawkular-metrics-certificate -n openshiftinfra -o jsonpath='{.data.hawkular-metrics-ca\\[\\].certificate}' | base64 -d > hawkular-internal-ca.crt\n```"}}},{"rowIdx":72,"cells":{"id":{"kind":"string","value":"3911b32500121a348e39be95f0318d671bdf0917"},"text":{"kind":"string","value":"Licensing and Competition for Services in Open Source Software\n\nTerrence August∗\nRady School of Management\nUniversity of California, San Diego\n\nHyoduk Shin†\nRady School of Management\nUniversity of California, San Diego\n\nTunay I. Tunca‡\nSmith School of Business\nUniversity of Maryland\n\nMarch, 2013\n\nForthcoming in Information Systems Research\n\nAbstract\n\nOpen source software is becoming increasingly prominent and the economic structure of open source development is changing. In recent years, firms motivated by revenues from software services markets have become the primary contributors to open source development. In this paper we study the role of services in open source software development and explore the choice between open source and proprietary software. Specifically, our economic model jointly analyzes the investment and pricing decisions of the originators of software and of subsequent open source contributors.\n\nWe find that if a contributor is efficient in software development, the originator should adopt an open-source strategy, allowing the contributor to offer higher total quality and capture the higher end of the market while the originator focuses on providing software services to lower end consumers. Conversely, if the contributor is not efficient in development, the originator should adopt a proprietary software development strategy, gaining revenue from software sales and squeezing the contributor out of the services market. In certain cases an increase in originator development efficiency can result in increased contributor profits. Finally, we find that, somewhat counter-intuitively, an increase in contributor development efficiency can reduce overall social welfare.\n\n∗Rady School of Management, University of California, San Diego, La Jolla, CA 92093-0553. e-mail: taugust@ucsd.edu\n†Rady School of Management, University of California, San Diego, La Jolla, CA 92093-0553. e-mail: hdshin@ucsd.edu\n‡Smith School of Business, University of Maryland, College Park, MD 20742. e-mail: ttunca@rhsmith.umd.edu\n1 Introduction\n\nAs the employment of information technology in modern corporations broadens and evolves, software plays an increasing role in the efficiency of firms and their ultimate level of competitiveness. Consequently, implementation, integration and cost efficiency of software selection is crucial to a company’s overall information technology strategy. Emerging as a response to this need, in a field that has been traditionally served by proprietary software solutions, open source software has become more prominent in the past decade, and its availability and quality have increased dramatically. For example, products and applications based on Linux and Apache software initiatives are widely used today, and many other open source products such as JBoss (Java middleware) and MySQL (DBMS) have emerged and generated increased usage in recent years (Kontzer 2005, Brunelli 2005, and Broersma 2005).\n\nOpen source software is arguably of comparable or, in some cases, even higher quality than its proprietary counterparts in terms of technical features. But high quality software and useful features alone have little value to a business unless it is able to utilize them through a cohesive integration of its systems and business processes and can maintain these integrated systems up and running in a reliable fashion. In fact, integration is precisely where the open source software industry has concentrated its efforts in the last decade.\\footnote{Integration refers to getting software installed on a company’s servers and integrated with business processes and pre-existing information systems as effectively as possible to increase the overall quality of the solution provided. Support refers to ongoing maintenance of these integrated systems, from troubleshooting bugs which arise to efficiently providing security vulnerability patches and more. Information technology consulting often refers to the provision of human resources to advise, implement, and deploy IT solutions which may include custom-built applications that run on top of open source software. Altogether, the integration, support, and consulting offerings are generally referred to as services.} Firms realize what matters to customers is the trade-off between the quality of the open source software solution and the price they pay. Due to customers’ needs for value-added services, software companies now see potential in harnessing other developers’ contributions to open software while still maintaining a lucrative source of revenues binded to services rather than product sales (Vance 2009). Today, while product license sales is the dominant revenue model for software firms who elect to keep their products proprietary, integration, support, and consulting services have become the most widespread and promising revenue model for firms that choose an open source path (Watson et al. 2008).\n\nAn important question that emerges is when would it be in a software firm’s best interest to pursue an open source strategy. Strategic considerations play an important role in this decision. The highest\nquality services are expected to be offered by the firms who have invested the most effort into the open source project by contributing source code and managing the architecture of the software. Through their accumulated expertise, these firms have an advantage in the services market as they can provide the best integration with existing systems as well as most effectively provide support and consulting. However, with open source software, firms’ development efforts to improve quality of integration and services can also benefit other service providers. In particular, because service providers can use publicly available software documentation, service modules and utilities written by firms who have invested in development, they can provide more effective integration and support, and thus offer a higher quality software solution (LaMonica 2005, Virijevich 2005). Considering the effects of such complementarities on competition in the market for integration and support, investments on software development and building expertise gain additional strategic importance.\n\nWith open source software, diverse market environments can emerge. In certain cases, the software originator assumes the role of primary developer while subsequent contributors undertake useful but relatively minor development roles. Red Hat, with its JBoss division, leads development and dominates the services market for JBoss Application Server, which is an example of this setting (Kerstetter 2004, Sager 2005, Adamson 2005). In other cases, a small firm or organization may originate a software product, but a large outside firm leads investment toward the development of the software product, thus making significant contributions even though they are subsequent to the originator’s efforts. For example, IBM has over 700 developers working on open source software and self-reportedly plans to invest $1B into development and support of its projects in this domain (Capek et al. 2005). Similarly, HP has over 2,500 developers focused on open source projects (Hewlett-Packard 2007). These companies are strongly incentivized by the global services market. In 2007, IBM generated $55.3B from global services while only $20B from software (IBM 2007). The strategic interactions between these players determine the final market outcome and have an important role in shaping software development choice.\n\nIn this paper, we present a model that captures the economic incentives for firms to contribute to open source software development and then explore the strategic and policy decisions of a software originator and regulators, respectively. We explore joint development and pricing equilibria in software markets for both\nopen source and proprietary software strategies. If a firm chooses an open source strategy, she makes her source code publicly available which has several effects. First, the software receives a development boost as outside contributors help write and refine the product’s source code, as well as produce related modules and utilities. Second, the firm must rely heavily on services as the primary revenue source since her source code is freely available to users. Third, the availability of source code makes it easier for competitors in the services market to build expertise and improve the quality of their own offerings, which means the originating firm faces tougher competition in this market. For example, a large contributor such as IBM can dedicate vast resources to the development of an open source project in order to increase his mastery of the software and improve his services packages. This investment can both benefit and harm an originator operating in an open source environment. Alternatively, the originating firm may choose a proprietary option, in which case the source code of her product remains closed. In this case, the firm incurs the entire product development cost alone. On the upside, in addition to potentially charging for software and integration services, the firm retains the ability to charge a price per each copy of the product regardless of whether she provides the services aspect.\n\nUsing this model, we study three main issues: First, under both open-source and proprietary licensing strategies, we thoroughly examine and identify the equilibrium outcomes in a market for software where an originator and contributor invest in development and firms compete for revenues from providing services. Second, building on this equilibrium analysis, we explore how software development efficiency for both the originator and subsequent contributors impacts the originator’s choice of source code licensing strategy. Third, we study the implications of an open approach on social welfare. The U.S. government has recently begun to advocate open source development in certain circumstances and, more importantly, continues to play a significant role in setting policy to help increase the value generated by information goods in the economy (Herz et al. 2006). Accordingly, we also study social surplus, and provide insights into how governance and policy can utilize the economic incentives influenced by competition in the software services market to improve welfare.\n\nIn essence, what lies at the core of our paper is the management of two goods that are complements, namely the software and the integration and services provided for it. The main trade-off in this software\nlicensing decision with services is as follows: the originator can either develop a product alone and be able to charge for the software herself in return (proprietary strategy), or she can open up the source code to outside contributors to share the burden of investment in development but rely only on services and integration income for revenue, albeit with possibly higher quality of software and services thanks to the efforts of the contributor firm (open source strategy). There are a number of factors that play critical roles in determining the best licensing strategy such as the relative efficiencies of the originator and the contributor firms, and capabilities of the firms reaping benefits from each others’ software developments.\n\nContributor efficiency is a double-edged sword for the originator. When the contributor is strong in development efficiency and utilizing developments to improve quality, it can pay off for the originator to open the source code since this can result in significantly increased total software and service quality at little cost to the originator. However, a strong contributor can also be a formidable competitor that can steal significant market share. The originator has to balance these two factors when making her licensing decision. We find that if the originator is sufficiently efficient in development, her licensing decision mainly depends on her ability to harness the contributor’s development to improve quality: if the originator is adept at improving the quality of her software/service package by utilizing the contributor’s development, then an open source strategy is optimal, otherwise the originator is better off keeping the software proprietary.\n\nWe find that an increase in originator development costs can in fact decrease the originator’s service price and increase the contributor’s service price. This occurs because decreased originator development efficiency reduces originator effort in investment and increases differentiation between the originator and the contributor’s offerings. Consequently, the contributor can be better off by increasing his efforts in development, quality and price. We also show that increased contributor efficiency can unexpectedly decrease welfare. This result can manifest when the contributor is highly efficient because if the originator opens up the source code, the originator can be squeezed out of the services market as the contributor uses his development efficiency and strategic pricing to open up a large gap between the overall attractiveness of his offering and that of the originator. In such circumstances, the originator may instead choose a proprietary strategy, which results in lower software and service quality and decreased welfare.\n2 Literature Review\n\nOne of our key research goals in this paper is to explore the economic incentives of the developers and firms producing open source software. One primary question is why do developers contribute to a project without being paid for their effort, at least by traditional means. In the existing literature, researchers have empirically substantiated the existence of intrinsic motivations such as intellectual stimulation and community building as well as extrinsic motivations such as job market signaling and being paid to contribute (see, e.g., Lerner and Tirole 2002, Hars and Ou 2002, von Krogh and von Hippel 2006, Roberts et al. 2006, Iansiti and Richards 2006). However, to our knowledge, no study has investigated a theoretical model that explicitly structures the real monetary incentives and revenue sources of the firms that contribute to open source projects for profit under market competition. We focus on these incentives, which emerge through the market for services.\n\nRecently, the market for services has been recognized as a powerful extrinsic motivation for developers’ contributions to open source software (see, e.g., Raymond 1999, Lerner and Tirole 2002, Lerner and Tirole 2005a, Capek et al. 2005). The services market has the potential to generate significant revenues for contributors who invest in open source development. One reason is due to the existence of many indirect methods to capture a software program’s “sale value” which refers to its value as a salable commodity (Raymond 1999). Lerner and Tirole (2005a) note that for-profit firms such as IBM which offer services that are complementary to open source software have largely benefited in their consulting businesses. Watson et al. (2008) suggest that the contemporary second-generation open source (OSSg2) companies that generate the bulk of their revenues from services have the most promising business model in the open source domain. Our paper contributes to the open source software literature by formally analyzing the impact of the services market on the incentives of originator and contributor firms as profit-seeking entities.\n\nWhen one turns to the motivations of firms that profit from open source, revenues generated by providing implementation, integration and other related services turn out to be a significant factor. Iansiti and Richards (2006) empirically demonstrate that large IT vendors such as IBM and Oracle invest in open source software development projects that provide or complement revenues from applications and services\nthey provide. Watson et al. (2008) point to the fact that JBoss contributed 85%, 95%, and 60% of the total effort toward JBoss AS, Hibernate, and Tomcat, which are its three leading open source products, and the majority of JBoss’s revenues come from its provision of services. Further, for most open source projects, although there may be many independent, small service providers, the major contributors to development (other than perhaps the originators) are a small number of firms prominent in the specialty (Mockus et al. 2000, Kogut and Metiu 2001, Koch and Schneider 2002, Kuk 2006). Based on these empirical observations, our paper focuses on the motivations of firms both in development and competition, accounting for profit-motivated contribution incentives via a market for services.\n\nA major question we study in our setting is whether a software originator should choose to make her product proprietary or open source. Related to this question, Lerner and Tirole (2005b) predict proprietary projects that seem less likely to succeed may be turned into open source projects but will also face lower acceptance by the open community. Gaudeul (2004b) finds that proprietary strategies are favored when developer wages are closely balanced with their costs. Using a dynamic model of pricing and investment, Haruvy et al. (2008) study the problem in the context of an exogenous complementary product or service on the open source path.\n\nAdditionally, several papers look at direct competition between open source and proprietary firms (e.g., Gaudeul 2004a, Bessen 2006, Casadesus-Masanell and Ghemawat 2006, Lee and Mendelson 2008, Zhu and Zhou 2012). In this paper, unlike these existing studies, we focus on the competition in the services market for a given source code strategy. Our paper thus contributes to this literature by exploring the originator’s strategy of whether to proceed with an open source or proprietary strategy in consideration of the market for services.\n\n3 Model\n\nA software originator determines whether to pursue a proprietary or open source software licensing strategy, which we denote with \\(\\rho \\in \\{P,O\\}\\). Throughout the paper, we use superscripts \\(P\\) for proprietary and \\(O\\) for open source to indicate the licensing strategy. After the licensing decision, the originator invests in the\ndesign and development of the software product. A secondary firm, the contributor, may choose to put forth effort to invest in development and increase the quality of the software solution.\\textsuperscript{2} We denote the originator with subscript $o$ and the contributor with subscript $c$. In our model, we focus on a profit-motivated originator and a profit-motivated contributor who intend to generate revenues from offering software integration and other services to consumers. It is also important to note that there are typically other contributors to open source software that do not have commercial motivations. These contributors have non-strategic motivations such as hobbyism, altruism, and idealism. One can incorporate these non-strategic contributions from the open source software community as an exogenous, random additive component in the quality of the software and service for all providers, but this simple arithmetic shift would not alter the nature of the insights or the results from the model. In order to keep the model simpler, we will not incorporate this component in our model and analysis and, instead, maintain focus on contributors with strategic motivations.\n\nAfter purchasing or deciding to use the software, a consumer needs to have the software installed and integrated, i.e., obtain service, for it to become usable and the consumer to derive value from it. The value derived from software usage for a consumer depends on many factors including product features, reliability, integration with business systems and processes, and support. In turn, the quality (and hence the value to the consumer) of features such as integration and support depends on the provider of the service. A service provider firm with more expertise, better utility and support tools, and preparation provides a higher quality service. Each firm that provides service and integration essentially offers its own level of service quality, and the overall value a consumer derives from using the software depends on the firm it contracts to provide integration and service (see Raymond 1999 and Farber 2004, among others). A firm may improve its expertise and total quality by investing effort in these areas. Therefore, although under both licensing strategies both firms share the same software product, because of the potential difference in service qualities, the total quality of the offering of a firm, which we define as the combined quality of the software used and the service provided by that firm, can differ between the two firms. We denote the\n\n\\textsuperscript{2}Note, for simplicity, we include a single large contributor in the model. Further, in the market we study, contributions are extremely concentrated amongst very few contributors (see, e.g., Mockus et al. 2000, Koch and Schneider 2002, Kuk 2006), and it is often the case that a single large contributor emerges to compete against the originator and together dominate the market’s strategic interactions, as in the case of Apache Geronimo.\ntotal quality for the originator by $Q_o$ and the total quality for the contributor by $Q_c$. The total quality of the contributor firm’s offering benefits at a certain rate from the effort invested by the software originator toward development of the product. Furthermore, if the product is open source, the contributor’s additional developments are available to the public, so in that case, the total quality of the originator’s offering also benefits from the contributor firm’s efforts. Therefore, a software and related services marketplace with the possibility of open source licensing has an interesting characteristic: The originator and the contributor are complementary to each other in improving the total quality of the software and services while they also compete against each other in the marketplace for providing these services. The software policy chosen by the originator (i.e., proprietary or open source) changes the incentives for these two firms and therefore influences their strategic choices of effort invested in the software.\n\nThere is a continuum of consumers who have heterogeneous preferences on the total quality of a complete software solution they receive. We model this consumer type characteristic as uniformly distributed, $\\theta \\in \\Theta = [0,1]$ where $\\theta$ denotes a specific consumer’s sensitivity to quality or “type.” A consumer with type $\\theta$ obtains value $\\theta Q_o$, if she contracts with the originator and $\\theta Q_c$ if she contracts with the contributor.\n\nThe originator selects an effort in development $e_o \\in \\mathbb{R}_+$ and incurs a quadratic convex cost of effort $\\beta_o e_o^2/2$. Similarly, the contributor invests effort $e_c \\in \\mathbb{R}_+$ at a cost $\\beta_c e_c^2/2$ subsequent to the originator’s investment decision. Effort in open source development amounts to labor and resources, and, particularly in the software industry, firms exhibit significant variation in size and worker abilities, as well as differences in the shadow prices of worker time and resource availability for any given project. Therefore, $\\beta_o$ and $\\beta_c$ are in general different and firms demonstrate heterogeneity in this dimension (see, e.g., Oi 1983). Note that, for the originator, $e_o$ refers to the additional effort in development of the software beyond the base amount required for the release of the software in the minimal acceptable form.\n\nAs we mentioned above, depending on the software policy decision ($O$ or $P$) a firm’s offering will be positively impacted by other firms’ investments in publicly available open source code, service support components, utility contributions, and information. Under an open source policy (i.e., for $\\rho = O$), the total quality offered by the originator depends not only on her own effort $e_o^O$ but also on the effort exerted by the contributor such that $Q_o^O = s_{oo}^O e_o^O + s_{oc}^O e_c^O$. Similarly, the total quality for the contributor depends\non the originator’s effort and is given by \\( Q^O_c = s^O_{co}e^O_c + s^O_{cc}e^O_c \\). The parameters \\( s^O_{ij} > 0, i, j \\in \\{o, c\\} \\), indicate the effect of firm \\( j \\)'s effort on firm \\( i \\)'s total quality. The magnitudes of coefficients \\( s^O_{ij} \\) are largely determined by the particular software product market and the nature of the originator and contributor firms. These coefficients have a substantial economic and strategic significance. Their relative magnitudes are critical in determining the incentives of the firms to put effort into the software because a firm’s competitor benefiting from her effort at a high rate may curb her incentives to bear the costs of exerting that effort. Further, the relative magnitudes of these coefficients between proprietary and open source policies may also affect the originator’s licensing policy. As we will see more clearly in the following sections, these coefficients will play an important role in determining the outcome and the results.\n\nUnder a proprietary strategy, consumers who purchase the product can choose to use the originator’s services or contributor’s services. Since the source code is closed under this strategy, the contributor’s effort does not create returns toward the originator’s quality component, \\( s^P_{oc} = 0 \\). Note that \\( s^P_{oc} \\) is related to the benefit that the originator can obtain from developer effort. Under the proprietary strategy, it is harder for the originator to garner developer efforts to her advantage. For example, Microsoft may try to implement certificate programs to nurture new software. Some contributors may invest their efforts to earn the certificates. However, it is not directly related to enhancing the software quality nor to increasing Microsoft’s service quality. Consequently, \\( s^P_{oc} \\) is close to 0.\\(^3\\) Further, the closedness of the source code limits the contributor’s ability to improve his own quality factors and related offerings, i.e., \\( s^P_{cc} < s^O_{cc} \\). We consider \\( s^P_{oo} = s^O_{oo} \\) to be constant and independent of the originator firm’s strategy. In order to make a fair comparison between the profitability of the two business models, we hold this specific parameter constant and isolate the main effects that help each model to perform relatively better.\\(^4\\) In summary, for the proprietary case, \\( Q^P_o = s^P_{oo}e^P_o \\) and \\( Q^P_c = s^P_{co}e^P_o + s^P_{cc}e^P_c \\). Note that for simplicity in analysis, we assume that the originator is capable of better harnessing her own efforts in development to improve quality than the contributor can, i.e., \\( s^O_{oo} > s^O_{co} \\) and \\( s^P_{oo} > s^P_{co} \\). In many cases it is reasonable to expect that a software originator can do this because as the creator of the software, she is likely to have fundamental knowledge\n\n\\(^3\\)Technically, it is not required that \\( s^P_{oc} = 0 \\) in order to establish our results.\n\n\\(^4\\)It is mathematically not a problem to relax this specification, and all of our results would continue to hold if we allowed this parameter to be appropriately constrained to match desired settings.\nand expertise as well as control of the project direction, enabling her to better leverage her own efforts.\n\nConsumers’ usage decisions are made in the last stage. Under a proprietary strategy, the originator sets a price for the product \\( p^P \\) and a price for her services \\( p^P_o \\), while a contributor only sets a price for his services offering \\( p^P_c \\). Under an open source strategy, the pricing of integration and services still occurs \\( (p^O_o \\) and \\( p^O_c \\)), but the product price is zero \\( (p^O = 0) \\). For simplicity, throughout the paper, we assume that the cost of providing service for the firms is zero.\n\nIn the proprietary case, a consumer with type \\( \\theta \\) chooses one of the following: not use the software product, purchase both the product and services from the originator, or purchase the product from the originator while obtaining services from the contributor. Her net payoff from each action is given by\n\n\\[\nV^P(\\theta) = \\begin{cases} \nQ^P_o \\theta - p^P - p^P_o & \\text{if purchased and service is contracted with the originator;} \\\\\nQ^P_c \\theta - p^P - p^P_c & \\text{if purchased and service is contracted with the contributor;} \\\\\n0 & \\text{if not purchased.}\n\\end{cases} \\tag{1}\n\\]\n\nUnder an open source strategy, the originator forgoes revenues from product sales while focusing on the services market. In this case, the consumer’s net payoff is given by\n\n\\[\nV^O(\\theta) = \\begin{cases} \nQ^O_o \\theta - p^O_o & \\text{if service is contracted with the originator;} \\\\\nQ^O_c \\theta - p^O_c & \\text{if service is contracted with the contributor;} \\\\\n0 & \\text{if not used.}\n\\end{cases} \\tag{2}\n\\]\n\nThe complete software and services total qualities \\((Q^P_o \\) and \\( Q^O_o \\), and \\( Q^P_c \\) and \\( Q^O_c \\)) differ under each source code strategy due to varying investment incentives as well as certain quality cross-effect parameters \\( s^P_{ij} \\) and \\( s^O_{ij} \\) differing for the two source code strategies.\n\nIn summary, the timeline for our model is as follows:\n\n1- The originator chooses a licensing strategy, \\( \\rho \\in \\{P, O\\} \\), either making the product proprietary or open source.\n\n2- The originator invests in developing the software, \\( e_o \\).\n3- Knowing whether the software is proprietary or open source and having observed the originator’s effort in software development, $e_o$, the contributor decides whether to offer services for the software and how much to invest in further development, $e_c$.\n\n4- The originator observes whether the contributor is in the market and, if so, the contributor’s level of software development.\n\n5- Both firms simultaneously price their offerings, i.e., the originator and the contributor set their prices for services, $p_o^\\rho$ and $p_c^\\rho$, respectively, for $\\rho \\in \\{O, P\\}$. In addition, if the product is proprietary, the originator sets the unit price for the product, $p_P$, simultaneously as well.\n\n6- Each consumer chooses whether to use the product and from which firm to purchase services. The market clears.\n\n4 Source Code Strategies\n\n4.1 Proprietary Strategy\n\nIn the commercial software industry, firms have traditionally pursued proprietary strategies which use product revenues to recoup software development costs and generate return on investment. Corporations such as SAP, Oracle, and Microsoft have developed leading software products in their respective markets, and all have chosen to keep their products’ source code mostly closed and generate revenues from selling licensed copies. However, as we also discussed above, in order to derive full benefits from using the software, consumers also need to spend money and resources to procure integration and support. Software originators who choose to develop their software as a proprietary product typically offer these services as well. Furthermore, service offerings need not necessarily be made separate but may be bundled with the product itself.\n\nBy adopting a proprietary strategy, the originator makes a strategic choice to not permit secondary developers to contribute to or build upon the core codebase of the product. Although the firm typically offers Application Programming Interfaces (APIs) that permit selective extensions to software functionality,\ncustom code written for an API is often user-specific and limited in potential scope. By opting for the firm’s services package, a user benefits in several ways. First, by developing and managing the software product, the firm has accumulated expertise which it can leverage to provide a higher quality solution to the customer. Second, the firm can adapt its software product to include specific functionality requested by clients, and, further, this functionality can be built into the product for future releases which then require less maintenance of custom code by users. In this section, we investigate how an originator sets prices for her product and services and chooses investment in overall quality at the product development stage. We characterize the optimal profits obtainable using a proprietary strategy and use it as a benchmark for comparison to the outcome under open source.\n\n4.1.1 Consumer Market Equilibrium\n\nGiven the effort levels, \\( e_o^P \\) and \\( e_c^P \\), and prices, \\( p^P \\), \\( p_o^P \\), and \\( p_c^P \\), each consumer of type \\( \\theta \\) chooses whom to contract in order to maximize her net payoff given in (1) which reflects the choices for obtaining services. The characterization of equilibrium consumer behavior is symmetric, dependent on whether the originator or contributor offers a higher total quality. In either case, the prices are chosen such that one of the following outcomes occurs: (i) no consumer uses the software; (ii) consumers purchase the product from the originator, and all of them elect to be serviced by the firm offering a higher total quality; (iii) consumers purchase the product from the originator, and all of them elect to be serviced by the firm offering a lower total quality; and (iv) consumers purchase the product from the originator, and they further segment such that lower (higher) types elect to be serviced by the lower (higher) quality firm.\\(^5\\)\n\nFigure 1 illustrates these regions of the consumer market equilibrium. Because of symmetry, the figure focuses on the case where the originator is the quality leader, i.e., \\( Q_o^P > Q_c^P \\). When the originator’s service price is sufficiently low compared to the contributor’s service price, the originator’s service is a more attractive offer as her price is low for her quality level compared to the price/quality offering of the contributor. In such a case, every consumer who purchases the product will prefer to get services from the\n\n\\(^5\\)The complete mathematical characterization of the consumer market equilibrium and these regions is given in Lemma OS.1 in the online supplement. For ease of exposition, technical statements of all lemmas and propositions, as well as their proofs, are placed in the online supplement.\noriginator, i.e., the contributor is squeezed out of the market. If the contributor’s service price is lower, then consumers with a stronger preference for quality, i.e., those with higher $\\theta$ values, still prefer to contract with the originator for services, while certain consumers with lower $\\theta$ values will now choose to acquire the contributor’s services; for them, the contributor’s price will be more attractive than the originator’s, better justifying the quality of his service offering as can be seen in panel (b) of Figure 1. Finally, if the contributor’s service price is sufficiently low compared to that of the originator’s, all consumers will find purchasing services from the contributor to be more attractive than purchasing services from the originator. In this case, consumers will either not use the software or obtain services from the contributor after purchasing the software. The consumer market structure that results for this case is illustrated in panel (c) of Figure 1.\n\n4.1.2 Consumer Market Pricing\n\nNext, we present and discuss the consumer market pricing equilibrium taking the development effort levels for the originator and the contributor as fixed. Given their respective effort levels, $e^o_P$ and $e^c_P$, in the pricing stage of the game, the firms compete in the services market by setting their service prices to maximize their profits taking each other’s prices as given. The Nash equilibrium outcome of this stage of the game yields the equilibrium service prices denoted by $p^o_P(e^o_P, e^c_P)$ and $p^c_P(e^o_P, e^c_P)$, which are functions of the effort levels the firms chose earlier in the game. The following proposition describes how the originator and contributor set prices in equilibrium.\n\n**Proposition 1** Given the effort levels of the originator and contributor, the equilibrium software and services pricing outcomes are characterized as follows:\n\n(i) If the originator is the quality leader, she sets the software price as a monopolist and prices her services at cost such that she is the only firm actively servicing consumers in equilibrium. The contributor is forced out of the market.\n\n(ii) If the contributor is the quality leader, then the originator adjusts the software price reflecting the contributor’s effort level, and she provides a discount to users who opt to consume her services.\nThe contributor sets a service price above cost that mirrors the originator’s discount, and both firms actively service consumers in equilibrium.\n\nPart (i) of Proposition 1 states that if the originator’s service is of higher quality than the contributor’s then the contributor cannot compete with the originator in the services market because the originator will price the product to maximize revenue from software sales, while setting her service price to zero to squeeze the contributor out of the services market. As a consequence, she essentially offers a bundle of product and service as a monopolist and sets the “total price” of the bundle at the monopoly price. At these price\nlevels, the contributor is forced out of the market completely, since in order to gain any positive market share, she has to price her integration service offering below cost, i.e., below zero, which would result in losses. Therefore, the contributor is effectively forced out of the market.\n\nOn the other hand, if the contributor is the quality leader for services, then he has an advantage with the high valuation consumers (i.e., high $\\theta$ consumers) over the originator. Part (ii) of Proposition 1 states that in this case, in equilibrium, the originator chooses to share the services market with the contributor, utilizing the high quality of the contributor’s services to boost sales of her software product at the high end of the market. At the same time, she sets her service price negative to maintain price pressure on the contributor who is offering high total quality, which helps to increase revenues from the product among those who prefer to purchase services from the contributor.6\n\n4.1.3 Determination of Development Effort Levels\n\nUsing the equilibrium outcome for product and service prices provided in Proposition 1, we can analyze the equilibrium effort investment levels for the two firms. Given the effort of the originator ($e^{P}_{o}$) and using the equilibrium price expressions characterized in the proof of Proposition 1, we can derive the contributor’s profit as a function of his effort level, $e^{P}_{c}$.\n\nFrom this function, one can observe that given the originator’s effort level, if the contributor’s effort level is sufficiently low, the originator is the quality leader; whereas, when the contributor puts sufficient effort in development, he becomes the quality leader. As a best response to the originator’s effort level, the contributor chooses an effort level to maximize his profit, and the following proposition summarizes the solution to the decision problem he faces.\n\n**Proposition 2** Given the originator’s effort level $e^{P}_{o} > 0$, the contributor’s best response effort level $e^{P}_{c}(e^{P}_{o})$, and the resulting consumer market equilibrium is characterized as follows: There exists a critical\n\n---\n\n6By part (ii) of Proposition 1, it is in the originator’s best interest to enforce that consumers who purchase the service from her and enjoy the discount, indeed get the service from her. This would prevent higher valuation consumers, who prefer the contributor’s higher quality service, from purchasing service from the originator just to get the discount and to actually have service performed by the contributor. So, the agreements are set to be binding in that by contracting with the originator for the service, customers agree to be serviced exclusively by the originator. This is naturally enforceable by monitoring the source of service for each customer. This information is verifiable electronically as well as in person because service work is typically ongoing.\n\n7The full closed form expression for the contributor’s profit as a function of his effort level is given in equation (OS.19) in the online supplement.\nthreshold value, \\( \\bar{e}_o > 0 \\), where\n\n(i) If the originator’s effort level is less than \\( \\bar{e}_o \\), then the contributor’s investment in development level is positive and the contributor becomes the quality leader in the market with both firms actively serving segments of the consumer market;\n\n(ii) If the originator’s effort level is above \\( \\bar{e}_o \\), then the contributor does not invest in development and remains out of the market.\n\nIf the originator’s effort level is small, then the contributor has an opportunity to leapfrog the originator’s quality by investing heavily in development and bringing to market a services package preferred by higher valuation consumers. When the originator’s development effort level is low, the contributor seizes this opportunity, and becomes the quality leader. On the other hand, if the originator puts sufficient effort into development, then the contributor faces very different prospects. In this case, his efforts will not yield sufficient returns to cover his costs, so, his best response is not to invest in development at all. Consequently, the originator is the quality leader and becomes the sole firm actively serving the consumer market.\n\nProposition 2 describes how the contributor responds to feasible effort investments by the originator. Utilizing this characterization, in particular the mathematical characterization detailed in the online supplement, we next examine how the originator then chooses her effort level \\( e^P_o \\) to maximize her own profit \\( \\Pi^P_o \\). Substituting the contributor’s effort best response function and the equilibrium prices, we can write the originator’s profit as a function of her effort level \\( e^P_o \\). Studying this function, one can see that if the originator does not invest sufficiently in the software, i.e., \\( e^P_o \\leq \\bar{e}_o \\) where \\( \\bar{e}_o \\) is as given in Proposition 2, then as we have seen above, the contributor puts substantial effort and becomes the quality leader. In this case, if the contributor is efficient enough in development (low \\( \\beta_c \\)), the originator also benefits from his efforts. In this case, the originator’s profit in fact increases as \\( \\beta_c \\) decreases. On the other hand, if the originator makes a sufficiently large investment in the software, i.e., \\( e^P_o \\geq \\bar{e}_o \\), then, by Proposition 2, the contributor\n\n---\n\n*The closed form mathematical expression for \\( \\bar{e}_o \\) as well as the investment levels for the contributor are given in the proof of this proposition in the online supplement.\n\n**The full closed form expression for the originator’s profit as a function of her effort level is given in equation (OS.20) in the online supplement.\nis out of the market, and the originator can become the monopolist. Considering and comparing these outcomes, the originator determines the amount of effort to put into software development that maximizes her profits. Her decision, hinges on the development efficiency of the contributor, $\\beta_c$. We first examine a case where the contributor is highly efficient in development. The following proposition describes how the originator optimally leverages such an efficient contributor.\n\n**Proposition 3** If the contributor’s development costs are low, i.e. if $\\beta_c$ is sufficiently small, then, in equilibrium, both the originator and the contributor are active in the services market and the contributor is the quality leader. Only consumers with types in the range $[\\frac{1}{2}, 1]$ purchase the software. The originator serves the consumers with types in $[\\frac{1}{2}, \\frac{2}{3}]$ and the contributor serves those with types in $[\\frac{2}{3}, 1]$.\n\nIf the contributor is cost-efficient in development, then the originator invests a relatively small amount, which encourages the contributor to invest effort in the software and capture the high end of the consumer market. This benefits the originator because greater investments by the contributor will also make the originator’s software product and service offerings more attractive to customers which, in turn, boosts her revenue. As a result, in this regime, the originator enables the contributor to put in sufficient effort to become the quality leader and actively serve the higher valuation (i.e., high $\\theta$) customers. Likewise, the originator not only profits from software sales but also shares the service market by serving a lower valuation segment of the consumer population.\n\nNext, we examine the opposite case in which the contributor is highly inefficient in his cost of effort toward software development. Under a proprietary strategy, a cost-inefficient contributor offers limited value to the originator. As a result, the originator prefers to become the sole provider in the services market; we formally establish this result in the following proposition. Later, we will see that a contributor with similar characteristics is leveraged quite differently under an open source strategy.\n\n**Proposition 4** If the contributor’s development costs are high, i.e. if $\\beta_c$ is sufficiently large, then in equilibrium only the originator is active in the services market. Only consumers with types in the range $[\\frac{1}{2}, 1]$ purchase the software and services from the originator.\nWhen the contributor is not very efficient, it is costly for the contributor to put in significant effort, and it becomes much easier for the originator to push him out of the services market. Consequently, the originator invests substantial effort in software development, which in turn discourages the contributor to make any investment in the software; essentially, the contributor does not enter the market. That is, a software originator who faces an inefficient contributor will choose to invest heavily and capture the entire services market.\n\n4.2 Open Source Strategy\n\nAs an alternative to the traditional proprietary strategy, a software originator firm can adopt an open source strategy in which the source code is opened to other entities such as developers and users. One of the core features of the Open Source Definition is that the source code of the software product must be made available (Coar 2006). As a business model, there are many significant advantages to an open approach which leverages the knowledge and resources found in an open community. The originator’s cost of development is lower since she can benefit from the contributions of other developers toward both improving the software and writing utilities and other support code helpful in integration and maintenance of the product. In an open approach, the source code is made freely available in which case charging for the base software product itself is not feasible. However, because consumers value services, firms generate the bulk of their revenues by providing integration, support, and consulting.\n\n4.2.1 Characterization of Consumer Market Equilibrium\n\nSimilar to Section 4.1, we will start by exploring the consumer market equilibrium, and we will roll back the solution to effort levels and licensing strategy subsequently from there. Given the effort levels, \\( e^O_o \\) and \\( e^O_c \\), and prices, \\( p^O_o \\) and \\( p^O_c \\), each consumer of type \\( \\theta \\in \\Theta \\) chooses whom to contract with in order to maximize her net payoff given in (2) which reflects the choices she has for obtaining services. The characterization of consumer behavior in equilibrium is once again symmetric, dependent on whether the originator or contributor offers a higher total quality. Further, the four outcomes described at the beginning of Section 4.1.1 are also all feasible under an open source strategy. Figure 2 illustrates the consumer market\nequilibrium as is fully mathematically characterized in Lemma OS.2 in the online supplement for the case when the originator is the quality leader, i.e. $Q^O < Q^C$.\n\nIf both firms set their prices too high, no consumer will buy services and hence no consumer will choose to use the software. If either the contributor is pricing too high or if the originator is pricing low enough to make her services more attractive than that of the contributor for all consumer types, then all purchasing customers contract with the originator as is illustrated in panel (a) of Figure 2. On the other hand, if neither firm’s price is too high and the originator’s price is not too low to drive the contributor\nout of the market then the two firms share the services market, with the contributor serving the lower end of the user population. This consumer market structure can be seen in panel (b) of Figure 2. Finally, if the contributor’s price is sufficiently low and the originator’s price is sufficiently high, then despite the originator having the higher quality, all customers who use the software prefer to contract with the contributor and the originator is out of the market. This can be seen in panel (c) of Figure 2. The outcome for the case when the contributor is the quality leader has exactly the same structure except the roles for the originator and the contributor are reversed.\n\n4.2.2 Pricing in the Consumer Market\n\nGiven their respective effort levels, $e^O_o$ and $e^O_c$, in the last stage of the game, the firms compete in the services market by setting their respective prices to maximize their profits taking each other’s prices as given. The Nash equilibrium outcome of this final stage game yields the equilibrium service prices denoted by $p^O_o(e^O_o, e^O_c)$ and $p^O_c(e^O_o, e^O_c)$, which are functions of the effort levels the firms chose in the earlier stages. The following proposition describes how the consumer pricing equilibrium emerges and shapes up the market (full mathematical characterization of the prices are given in the proof of the proposition in the online supplement). \n\n**Proposition 5** Given the effort levels of the originator and contributor, the equilibrium software and services pricing outcomes characterize the market as follows:\n\n(i) If either the originator or contributor serves as the quality leader, then both firms are active in the services market, each serving a positive mass of the consumer population. The equilibrium prices switch symmetrically when the role as quality leader is reversed.\n\n(ii) If neither firm serves as quality leader (i.e., they offer equivalent total quality), then the firms engage in Bertrand competition which gives rise to both firms pricing at cost in equilibrium.\n\nProposition 5 presents an interesting statement: When the firms’ service qualities are not equal, in equilibrium, the originator and the contributor set prices such that both firms serve a positive market share\nof the consumer population. That is, in equilibrium, among all possible regions demonstrated in Figure 2, only the outcome illustrated in panel (b) where both firms participate in an active duopoly with positive market shares, can emerge. For each firm there is always some benefit of setting a small, positive price to capture a portion of the low end of the consumer population, and hence, none of the firms can force the other one out of the market. As a consequence, in equilibrium, the firms settle to a shared oligopolistic market. On the other hand, if the firms’ qualities are equal, then they engage in Bertrand style competition that drives their equilibrium prices down all the way to their cost of providing service, which is zero.\n\n4.2.3 Equilibrium in Investment Efforts in Development\n\nUsing the equilibrium outcome for service prices presented in Proposition 5, we can now analyze the equilibrium in effort investment levels for the two firms. Given $e^O_o$ and substituting the equilibrium service prices, we can write the contributor’s profit as a function of his effort investment level. Further, we can fully characterize the best response function of the contributor. We provide the complete, detailed expressions for his profit function and his optimal effort level $e^O_c(e^O_o)$ in Lemma OS.3 in the online supplement and summarize them in this section. If the originator is able to benefit from the contributor’s effort better than the contributor can himself (i.e., if $s^O_{oc} \\leq s^O_{co}$), or if the contributor’s effort level $e^O_c$ is smaller than a threshold, then the originator is the quality leader. Otherwise, the contributor is the quality leader. Further, in both cases, the contributor’s profit function is strictly concave in his own effort $e^O_c$ for any given originator’s effort level $e^O_o$.\n\nThe contributor’s effort investment level critically depends on two factors, namely (i) how strongly the originator can benefit from development efforts to improve her total quality and (ii) the originator’s effort level. First, if $s^O_{oc} \\leq s^O_{co}$, then $Q^O_o = s^O_{oo}e_o + s^O_{oc}e_c \\geq Q^O_c = s^O_{co}e_o + s^O_{cc}e_c$, i.e., the originator is the quality leader for all effort levels $e_o, e_c \\geq 0$. In this case, the contributor chooses an effort level to boost his own quality and captures a lower segment of the market while the originator serves the top tier of the market. A similar situation arises when the originator puts in a significant amount of effort in development. In such an instance, the originator’s quality is too high and even if the contributor can exceed the originator’s quality by investing sufficient effort, it does not pay off for him to do so; consequently, $e^O_c$ is small and\ncan even be zero, again resulting in the originator being the quality leader. However, when the originator\ncannot benefit from her own effort as efficiently (i.e., when $s_{oc}$ is sufficiently small), or when the originator’s\neffort level is low, the contributor faces a dilemma: Putting in substantial effort can make him the quality\nleader in the market but it could also benefit the originator, who needs the extra development effort from\nthe contributor to boost her own quality. On the other hand, the contributor may put forth a lower effort\nlevel and remain the quality follower. In such cases, the contributor has to choose between one of these\noptions and can even choose to invest no effort and become the lower quality service provider in order to\nnot benefit the originator at all. As a result, the contributor compares his options and chooses the one\nthat maximizes his profit.\n\nUsing our characterization of the contributor’s optimal effort level $e^{O\\ast}_c(e^O_o)$ as a best response to the\noriginator’s effort level $e^O_o$, we can turn attention to the originator’s effort investment problem. Based on\nher own effort level, the originator faces two separate possibilities. First, she may choose not to invest\nmuch effort in development and let the contributor become the quality leader. Second, she may choose to\ninvest a substantial effort and compete as the quality leader. Each of the two cases imply a different profit\ncurve for the originator corresponding to these two different effort regions. The originator then chooses\nher optimal effort level within each region, and subsequently selects the optimal effort that maximizes her\nprofit comparing those two regions. The resulting outcome again hinges on the development efficiency\nof the contributor. The following two propositions characterize the equilibrium outcome under an open\nsource software license.\n\n**Proposition 6** If the contributor’s development costs are low, i.e. if $\\beta_c$ is sufficiently small, then, in\nequilibrium, the contributor becomes the quality leader. In this case, if the contributor’ ability to benefit from\nhis own effort ($s_{oc}$) is sufficiently lower that the originator’s ability to benefit from that effort ($s_{oc}$), then\nthe originator invests no effort in development beyond the minimal release of the software, i.e., $e^{O\\ast}_o = 0$.\nOtherwise, the originator invests a positive effort in development. The contributor serves the top segment\nof the market and the originator serves a middle segment.\n\nAn illustration of how equilibrium decisions are made in the case of Proposition 6 (for small $\\beta_c$) is\nFigure 3: The contributor’s profit given the originator’s effort, the best response function of the contributor, and the originator’s profit.\n\npresented in Figure 3. The parameter values are $s_{oo}^{O} = 10$, $s_{oc}^{O} = 8$, $s_{cc}^{O} = 10$, $s_{co}^{O} = 1$, $\\beta_o = 5$, and $\\beta_c = 0.15$.\n\nPanel (a) demonstrates the contributor’s profit maximization: Given the effort level $e_o^{O}$ of the originator, the contributor chooses whether to invest sufficient effort to become quality leader ($Q_c^{O} > Q_o^{O}$) or to invest less effort and become the low quality service provider ($Q_o^{O} > Q_c^{O}$). In this example, the contributor chooses $e_c^{O \\ast}(e_o^{O})$ as the interior maximizer of the region in the right-hand portion of panel (a), which leads to the contributor serving as quality leader. Panel (b) shows the best response function of the contributor to the originator’s effort investment level. As the originator’s effort becomes larger, beyond a certain point, the contributor’s optimal effort level jumps down from the maximizer of the case where he is quality leader to the maximizer of the case where he serves as the lower quality provider. Finally, in the first stage of the game, taking the contributor’s best response $e_c^{O \\ast}(e_o^{O})$ into account, the originator chooses her equilibrium development investment level $e_o^{O \\ast}$ to maximize her profit. In the case illustrated in panel (c) of Figure 3, since $\\beta_c$ is small, the originator chooses not to invest beyond the minimal release of the software (i.e., $e_o^{O \\ast} = 0$), effectively inducing the contributor to invest high and become the quality leader.\n\nIn contrast, if the contributor is not very cost efficient in development, the originator becomes the quality leader. The following proposition summarizes the outcome.\n\n**Proposition 7** If the contributor’s development costs are high, i.e. if $\\beta_c$ is sufficiently large, then the originator invests a positive effort in development and becomes the quality leader, serving the top segment\nof the consumer population. The contributor as the lower quality service provider is still active and serves a middle consumer segment.\n\nIn equilibrium, both firms are active in the consumer services market. This market structure corresponds to the one demonstrated in panel (b) of Figure 2. The lowest segment of the consumer market with types below those that contract with the originator and the contributor does not use the software.\n\n5 Efficiency, Licensing, and Welfare\n\nOne argument favoring an open source approach is that there are significant potential gains if the efforts of outside developers are harnessed to develop a superior product. This strategy leverages the input from external contributors to identify and correct bugs and vulnerabilities, as well as govern software design and future direction. Notwithstanding these benefits, the options for a software vendor to generate revenues become limited. Openness of the code essentially means that the software product is free, therefore any consumer surplus that arises as a direct result of value derived from the base product itself is difficult to appropriate. The success of an open source business model must then lie in its ability to associate more of the intrinsic value of the software with the services component. However, the software originator still must compete for the appropriation of this surplus in a contested services market. In this section, we investigate how development cost efficiency impacts the profitability of an open approach and, consequently, the originator’s optimal strategy.\n\n**Proposition 8** When contributor’s development costs ($\\beta_c$) are sufficiently low, an open source strategy is attractive for the originator, whereas when contributor’s development costs are high, a proprietary strategy is attractive.\n\nWhen the contributor’s development cost efficiency is high, i.e., when $\\beta_c$ is low, an open source strategy is attractive for the originator because she can utilize his contributions which will significantly increase the quality of her offering through cross-effects. However, since the contributor’s development costs are low, under an open source policy, he is also a stronger competitor for the originator in the services market, which is her only source of revenue under an open-source strategy. Proposition 8 states that when the\nThe Effect of Development Cost Efficiency on Source Code Strategy\n\nThe impact of contributor cost efficiency on the originator’s software source code strategy.\n\nAs we discussed above, it is optimal for the software originator to employ an open-source strategy when the contributor’s development costs are sufficiently low as stated in Proposition 8 and as shown as Region II.\n\nOther parameter values in the figure are \\( s^{O}_{oo} = 10, s^{O}_{oc} = 8, s^{O}_{cc} = 10, s^{O}_{co} = 1, s^{P}_{co} = s^{P}_{cc} = 0 \\), and \\( \\beta_o = 5.0 \\).\nI in the figure. What is further interesting is that the originator chooses the open source strategy when the contributor’s effort benefits himself more than the originator, i.e., $s_{oc}^O > s_{oc}^O$. In fact, in equilibrium, the contributor incurs substantial investment in development and becomes the quality leader in the market for services, while the originator serves the lower tier of the market. Starting from a low $\\beta_c$, the figure illustrates that a decrease in contributor efficiency (i.e., an increase in $\\beta_c$) makes the proprietary strategy more preferable. Specifically, as the contributor’s development cost ($\\beta_c$) increases as can be seen in Region II, under an open source policy, neither the contributor has incentives to invest heavily to benefit the originator, nor can the originator make enough revenues in the services market. Instead, the contributor utilizes his cost efficiency to invest in development up to a point where his quality offering is quite attractive relative to the originator’s offering, but not high enough so there is still strong price competition to hurt the profits. Therefore, the open source strategy is unattractive to the originator and she chooses the software to stay proprietary.\n\nHowever, as contributor efficiency even further decreases, i.e., the contributor’s development cost ($\\beta_c$) increases, as can be seen in Region III, an open source strategy can again become optimal. In this region, the originator can establish enough differentiation as the quality leader to make an open source strategy more profitable than solely incurring the entire investment along the proprietary path. As a consequence, decreased contributor efficiency makes the open source policy optimal for the originator. But, as we also discussed above, a further increase in $\\beta_c$ reduces the potential quality improvement coming from the contributor under an open-source strategy and makes the proprietary path preferable for the originator, as also stated in Proposition 8 and illustrated in Region IV in Figure 4.\n\nProposition 8 and the discussion above provide insight into how the contributor’s cost efficiency impacts the originator’s source code strategy. Further, under a resultant open source strategy, i.e., when the contributor’s development costs are sufficiently low, the originator’s development cost efficiency has interesting implications on the equilibrium outcome. The following proposition presents these results.\n\n**Proposition 9** When the contributor’s development costs ($\\beta_c$) are sufficiently low and the originator cannot benefit strongly from the contributor’s effort (i.e., when $s_{oc}^O$ is low), increased costs of development for the originator (i.e., increased $\\beta_o$) can decrease the originator’s service price and increase the contributor’s\nservice price and profits.\n\nWhen determining the effect of the originator’s development efficiency on the equilibrium outcome, several factors play important roles. First, as a direct effect, as the originator becomes less cost efficient, i.e., as $\\beta_o$ increases, she invests less effort in development and thus offers a lower quality package in the services market. As stated in Proposition 9, the originator accordingly decreases her price in equilibrium. However, counteracting strategic factors make the net effect of this decreased development efficiency on the contributor bi-directional. First, increased originator development costs reduce the effort the originator puts toward improving software quality. Hence, the total quality of the contributor’s offering decreases which places downward pressure on the contributor’s price. On the other hand, a decrease in originator effort and her total quality can also imply improved differentiation between the offerings of the two competing firms. Consequently, the firms face relaxed price competition in the services market as they vie for contracts. In particular, if the power of the originator to harness her own investment in the services market ($s^{O}_{oo}$) is relatively high compared to that of the contributor to harness the originator’s effort ($s^{O}_{co}$), the second effect can dominate so that, in equilibrium, the contributor’s price increases with decreased originator efficiency. In this case, since the originator cannot benefit much from the contributor’s efforts, i.e., since $s^{O}_{oc}$ is relatively small, the contributor becomes the quality leader in equilibrium (the equilibrium quality levels satisfy $Q^{O}_{c} > Q^{O}_{o}$). As can be seen in Proposition 9, the same effects are carried to the equilibrium\nprofits as well; the originator is worse off, despite the fact that, in such a case, she enjoys reduced intensity of price competition due to increased differentiation in the services market. The net effect of decreased originator efficiency can be either positive or negative with respect to contributor profits.\n\nOne final thing to note here is that, as demonstrated in Figure 5, Proposition 9 is applicable on a broad parameter region. In Figure 5, the gray shaded area, labeled A, is delineated by the parameter bounds and indicates the region (in terms of $\\beta_c$ and $s_{oc}$) where the proposition statement is applicable. The other parameter values used in the figure are $s_{oo} = 10$, $s_{co} = 1$, $s_{cc} = 10$, and $\\beta_o = 5$. As can be seen in the figure, unless either one of $\\beta_c$ and $s_{oc}$ becomes quite high, the results of the proposition are applicable.\n\nIt is also important to consider the welfare implications of software policy. Social welfare is the sum of consumer surplus and the profits of the firms in the market. We denote the quality of the higher quality firm in equilibrium by $Q_H$ and that of the lower quality firm by $Q_L$ (i.e., if $Q_o \\geq Q_c$ then $Q_H = Q_o$ and $Q_L = Q_c$, and vice-versa). Similarly, we define $p_H$ as the service price of the higher quality firm and $p_L$ as the service price of the lower quality firm (and recall that the software purchase price is denoted by $p$, which is 0 if the software is open source). Finally, we define $\\theta_H$ as the lowest consumer type $\\theta \\in [0,1]$ that contracts service from the higher quality firm and $\\theta_L$ as the lowest consumer type that contracts service from the lower quality firm ($0 \\leq \\theta_L \\leq \\theta_H \\leq 1$). That is, the consumers with types above $\\theta_H$ contract service with the quality leader, and the consumers with types between $\\theta_L$ and $\\theta_H$ contract service with the low quality firm. In case there is only one firm providing service in the market in equilibrium, let $\\theta_L = \\theta_H$. Then the consumer surplus, $CS$, can be calculated as\n\n$$CS = \\int_{\\theta_H}^{1} (Q_H\\theta - p - p_H)d\\theta + \\int_{\\theta_L}^{\\theta_H} (Q_L\\theta - p - p_L)d\\theta. \\quad (3)$$\n\nHence, adding the originator’s and contributor’s profits, for different licensing strategies $\\rho \\in \\{P,O\\}$, total welfare is given by\n\n$$W(\\epsilon_o, \\epsilon_c) = CS + \\Pi_o^\\rho + \\Pi_c^\\rho = CS + p(1 - \\theta_L) + p_H(1 - \\theta_H) + p_L(\\theta_H - \\theta_L) - \\frac{1}{2} \\beta_c \\epsilon_c^2 - \\frac{1}{2} \\beta_o \\epsilon_o^2. \\quad (4)$$\nWe denote the equilibrium welfare under a proprietary strategy and an open source strategy with \\( W^P = W(e^{P*}_o, e^{P*}_c) \\) and \\( W^O = W(e^{O*}_o, e^{O*}_c) \\), respectively.\n\nOpenness of source code can boost the value software generates for the economy because it can lead to increased software quality; open source software development comes not only from the originator but also from contributors as well. Therefore, governments or regulating bodies may often have incentives to help promote greater contributions to open source development. However, in certain cases, the presence of a potential strong contributor may come with its downsides. The following proposition states this result.\n\n**Proposition 10** An increase in the efficiency of the contributor in both development costs (smaller \\( c \\)) and improving the quality of his service (larger \\( s^{P*}_{cc} \\)) may actually result in welfare losses by inducing the originator to strategically choose proprietary licensing instead of open source licensing.\n\nIn order to illustrate the intuition and the meaning behind Proposition 10, consider two cases: (i) the contributor’s development costs are low and his ability to improve the quality of his service under the proprietary regime is high; (ii) keeping everything else constant, the contributor’s development costs are high and his ability to improve the quality of his service under the proprietary regime is low. Denote the resulting welfare under case (i) by \\( W^{(i)} \\) and the welfare under case (ii) by \\( W^{(ii)} \\). First notice that in terms of direct effects, case (i) is strictly more favorable for welfare generation than case (ii). This is because both a reduction of development costs and an increase in the rate that development efforts generate software quality would be expected to directly contribute to the welfare. Yet, although a stronger contributor is expected to generate substantial value by improving quality, the strategic implications of having such a strong contributor can significantly impact the social benefit generated as stated in the proposition. Specifically, for case (i), with a stronger contributor, the originator chooses to keep the software proprietary while for case (ii), with a weaker contributor, she chooses to open the software. As a result, social welfare improves in case (ii), i.e., \\( W^{(ii)} = W^O(e^{O*}_o, e^{O*}_c) > W^P(e^{P*}_o, e^{P*}_c) = W^{(i)} \\).\n\nTo see the intuition here, suppose the contributor is strong and more capable of harnessing his own development efforts to improve his own quality, i.e., \\( s^{O*}_{cc} > s^{O*}_{oc} \\). Then he can capture significant market share of services under the open-source licensing strategy and since there are no revenues from selling the\nsoftware itself when the software is open, the originator’s profits can suffer by opening up the software. If in\naddition the contributor can harness his own efforts sufficiently well under a proprietary licensing strategy,\n(i.e., if $s_{cc}^P$ is sufficiently high) so that he would have strong incentives to contribute, the originator can\nchoose to keep the software proprietary. This is because, in such a case, the originator can collect revenues\nfrom selling the software while allowing the contributor to be the quality leader - such an approach enables\nsufficient differentiation between the service offerings due to high benefits the contributor reaps from his\nown efforts (i.e., high $s_{cc}^P$), avoiding cutthroat price competition. On the other hand, in the presence of\na relatively weaker contributor, provided that the contributor’s development of the open source software\ndoes not benefit himself too disproportionately in comparison to the originator, the originator can choose\nto open the source code. This is because the originator can benefit from the development efforts of the\ncontributor under the open-source strategy while avoiding intense price competition for services due to lack\nof sufficient differentiation under the proprietary scenario that would arise because $s_{cc}^P$ is low. In summary,\nsince the originator chooses the proprietary licensing strategy under case (i), social welfare can suffer due\nto loss of value generated for all users by obstructed open availability of the contributor’s development\nefforts and the reduced consumer usage caused by the requirement to pay for the software. Therefore,\ncontrary to what one might expect, a stronger potential contributor may, in fact, be worse for welfare.\n\n6 Discussion\n\nIn this paper, we studied the effect of profit-motivated service provision in open source software. We\nexamined a software originator firm’s proprietary versus open source licensing problem, facing a contributor\nfirm that can become a competitor. In this context, we explored the effects of several factors including the\noriginator and contributor development efficiencies and the ability of the originator and contributor firms\nto harness development efforts in improving the quality of their offerings.\n\nPrevious literature has studied various aspects of economic incentives of open source software. One\ndimension related to our study is motivations of individual contributors to open source projects. Studies\nhave identified career and ego-gratification incentives as well as skill and aptitude signaling factors (Lerner\nand Tirole 2002), and have demonstrated that paid participation and status motivations improve individuals’ development contribution levels to the software (Roberts et al. 2006). In contrast, our model focuses on the incentives of purely profit motivated firms who contribute to open source projects in order to generate revenues from the services market. Therefore, unlike the studies in the previous literature, our model captures the direct monetary profit motivations of contributor firms to a free software project. We explicitly model the collaborative nature of the open-source development efforts and how this gets impacted by the competition in the profit driven services market down the line. Our model enables us to identify some unique strategic motivations that arise from the economic dynamics of this situation. For instance, strong originators of open-source software may, in certain cases, choose not to invest in software development much in order to boost the incentives of potential contributors to invest in development, since low investment and expertise development by the originator creates increased opportunities for contributors to profit from the services market.\n\nAnother branch of the existing literature related to our paper is on open source versus proprietary software licensing decisions. Previous studies have found that free-riding can prevent materialization of certain open source software projects (Johnson 2002) and that complementary goods that can generate additional revenues can move incentives towards licensing the software as open-source (Haruvy et al. 2008). In our paper, we explicitly model and study competition from potential contributors in the services market and the effects of endogenous investments in software development, finding that a contributor efficient in development can prevent opening-up of the source code and in fact hurt welfare. There have also been studies that explore competition between firms related to the context of open-source software, but these studies had focused on competition between open-source and proprietary software providers (e.g., Gaudeul 2004b, Casadesus-Masanell and Ghemawat 2006, Lee and Mendelson 2008). Our modeling of the strategic interaction between the software originator and a potential contributor who can simultaneously be a collaborator and competitor also allows us to demonstrate interesting findings such as how increased originator development costs can in certain cases reduce originator’s service prices and may decrease the contributors’ profits.\n\nIn summary, the contribution of our study is two-fold: First, we present the first model to our knowledge\nthat explicitly studies the role of the market for services in open source software and the associated economic incentives and dynamics between the software originator and development contributor firms that are purely motivated by profits in the open source domain. This business model from services is fast growing in recent years and is becoming the dominant structure in open source software as empirically documented in Suarez et al. (2012). Second, exploring our theoretical model, this study provides many interesting conclusions that also have practical implications for software firms as well as policy makers as we summarized above. These findings also help open avenues for future, related empirical studies that explore the vast subject of open source software.\n\nOne finding from our study is that when the contributor is highly efficient in development, the originator is better off making the software open source. Facing a strong contributor, a proprietary licensing approach may not be very profitable for a relatively weak originator as the development of the software and the quality of service will be limited, lacking open contributions of a strong contributor. However, if the originator takes an open-source approach she can benefit from the improved development of the software significantly even if the strong contributor who can highly invest in the software becomes the quality leader and captures the higher value segment of the services market. In this case, the originator can benefit from the contributor’s development efforts and can profitably provide services to a lower tier of users. An example of this outcome is that of Apache Geronimo and IBM. Founders of Geronimo have offered services through Covalent Technologies while IBM continues to make large development investments and takes the quality lead. On the other hand, we also found that if the contributor is not efficient in development relative to the originator, the originator will not benefit much from the contributor’s development. In this case the originator is often better off keeping the software proprietary and generating revenues from software sales, while taking the quality lead and squeezing out or marginalizing the contributor in the services market. Microsoft is an example of a strong originator who has long utilized a proprietary strategy for its software product line. Our results suggest that one reason Microsoft may not adopt an open source strategy is because of the difficulty to engender a sizable contribution that it can harness from the developer community. Part of the reason is likely Microsoft’s bitter history with the open source movement. However, even Microsoft is continuing to adapt to new paradigms such as open source and cloud computing, and so\npursuit of an open source strategy in the near future is certainly possible with increased relative efficiency of the contributors’ software development.\n\nAnother interesting finding from our study is that an increase in the contributor efficiency is not always good for welfare. If the contributor is efficient in harnessing the originator’s development efforts to improve the quality of his own service and becomes highly efficient in development, the originator can be better off by keeping the software proprietary rather than opening the source code up to give an opportunity to a strong contributor who might dominate the market. In such cases, an increase in contributor development efficiency may result in welfare losses by influencing the originator’s source code strategy toward a proprietary one. Therefore, regulators should be careful in their approach toward supporting open source contributors’ activities. For instance, in certain cases imposing a small tax on open source development or associated revenues can help decrease prices and increase welfare.\n\nOur study has its limitations and restrictions, which give rise to paths for further analysis and future studies on the topic. Our focus in this study has been the market for services and how the corresponding economic incentives of contributors influence the choice of business model. There are several other factors that can also influence these decisions. For example, the success of an open source model also depends on how well coordination, uncertainty, hijacking, forking, and organization sponsorship are managed (see, e.g., Stewart et al. 2006). An important direction for future research is studying how profit-maximizing open source models are influenced by risks of forking and hijacking, and also the role organizational sponsorship and community support play. Bridging together the insights in this work related to services with those found in the other research streams in open source can substantially increase our overall understanding of this domain.\n\nIn this paper, for simplicity and clarity we assumed that the cost of providing the service for the firms was zero. Yet another possible avenue for future research is relaxing this assumption and exploring the effects of the changes in the magnitudes of the service costs on the strategic behavior of the firms. Increases in service costs can shrink the potential profits that could be made from the software market. This can alter the strategic positioning of the firms relative to each other with respect to the qualities of their products and in turn can affect the originator’s licensing choice. What is more, governments and policy makers can\ndirectly control the magnitude of the service costs by tax and subsidy policies. An extension of our model that studies the effect of the service costs on the equilibrium can shed light into the potential role of policy making on open source licensing decisions and the corresponding implications for welfare.\n\nIn our study, we use asymptotic analysis, which is commonly used in microeconomic studies. The use of asymptotic analysis can be expected here, as in many other studies with microeconomic models, due to the complexity of the problem and its solution characterization (some examples of studies that use this technique are, Li et al. 1987, Laffont and Tirole 1988, MacLeod and Malcomson 1993, Pesendorfer and Swinkels 2000, Muller 2000, Tunca and Zenios 2006, August and Tunca 2006, 2008, Pei et al. 2011 among many others). Miller (2006) and Cormen et al. (2009) give comprehensive treatments of the mathematical techniques used in asymptotic analysis. Please also see August and Tunca (2011) for further details and discussion on the rationale of the use of asymptotic analysis. We have characterized the solution and identified the regions under which the results and policy implications related to our research questions arise. Given the complexity of the setting, the boundaries of these regions do not have explicit functional forms. Such boundaries would normally be implicit and would be characterized as such. The goal of the analysis is identifying the characterization of the regions for applicability in terms of parameter characteristics, which is the focus of our results and our propositions.\n\nIn recent decades, open source software has become increasingly more prominent, and the economic landscape that governs its development has evolved significantly. The economics underlying open source software are inherently complex and uniquely multifaceted. Further, robust economic structures and instruments by which open source developers can turn their efforts into revenues have just started to clearly emerge as the path for open source software’s evolution. Formal analysis and research is needed to build an understanding of the underlying complex structures. Our analysis aims to provide such a formal approach to gain relevant insights into various aspects of this issue. The insights generated can provide guidance for software firms and policy makers alike and help generate future research to further our understanding and benefit from this valuable concept.\n\nAcknowledgments\nWe thank Michael Smith (the senior editor), Indranil Bardhan (the associate editor), and two anonymous reviewers as well as the seminar participants at the Graduate School of Management at the University of California at Davis and Marshall School of Business at the University of Southern California for valuable comments and suggestions. This material is based upon work supported by the National Science Foundation under Grant No. CNS-0954234.\n\nReferences\n\n\nA Notation\n\nFor the reader’s convenience, we summarize our model notation in the following table:\n\n<table>\n<thead>\n<tr>\n<th>Notation</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>$\\rho$</td>\n<td>Originator’s software strategy ($\\rho = P$ for proprietary, and $\\rho = O$ for open source)</td>\n</tr>\n<tr>\n<td>$\\theta$</td>\n<td>Consumer type $\\theta \\in \\Theta = [0, 1]$</td>\n</tr>\n<tr>\n<td>$e_o^c$</td>\n<td>Originator’s development effort level</td>\n</tr>\n<tr>\n<td>$e_c$</td>\n<td>Contributor’s development effort level</td>\n</tr>\n<tr>\n<td>$\\beta_o (e_o^c)^2 / 2$</td>\n<td>Originator’s cost of effort</td>\n</tr>\n<tr>\n<td>$\\beta_c (e_c^o)^2 / 2$</td>\n<td>Contributor’s cost of effort</td>\n</tr>\n<tr>\n<td>$s_{oo}^o$</td>\n<td>Impact coefficient of originator’s effort on her own total quality</td>\n</tr>\n<tr>\n<td></td>\n<td>($s_{oo}^P = s_{oo}^O$ and is independent of the originator’s software strategy)</td>\n</tr>\n<tr>\n<td>$s_{oc}^o$</td>\n<td>Impact coefficient of contributor’s effort on his own total quality</td>\n</tr>\n<tr>\n<td>$s_{oc}^c$</td>\n<td>Cross-firm impact coefficient of contributor’s effort on originator’s total quality</td>\n</tr>\n<tr>\n<td></td>\n<td>($s_{oc}^P = 0$ for proprietary)</td>\n</tr>\n<tr>\n<td>$s_{co}^o$</td>\n<td>Cross-firm impact coefficient of originator’s effort on contributor’s total quality</td>\n</tr>\n<tr>\n<td>$Q_o^o$</td>\n<td>Total quality of the originator’s offering (software and service)</td>\n</tr>\n<tr>\n<td></td>\n<td>($Q_o^O = s_{oo}^O e_o^o + s_{oc}^O e_c^o$ for open source, and $Q_o^P = s_{oo}^P e_o^o$ for proprietary)</td>\n</tr>\n<tr>\n<td>$Q_c^o$</td>\n<td>Total quality of the contributors offering (software and service)</td>\n</tr>\n<tr>\n<td></td>\n<td>($Q_c^O = s_{co}^O e_o^o + s_{cc}^O e_c^c$ for open source, and $Q_c^P = s_{co}^P e_o^o + s_{cc}^P e_c^c$ for proprietary)</td>\n</tr>\n<tr>\n<td>$p_o^o$</td>\n<td>Price charged by the originator for each unit serviced</td>\n</tr>\n<tr>\n<td>$p_c^c$</td>\n<td>Price charged by the contributor for each unit serviced</td>\n</tr>\n<tr>\n<td>$p_o^P$</td>\n<td>Price charged by the originator for each copy of the software (proprietary case)</td>\n</tr>\n<tr>\n<td>$V^P(\\theta)$</td>\n<td>Net payoff to purchasing consumer with type $\\theta$ under proprietary strategy</td>\n</tr>\n<tr>\n<td></td>\n<td>($Q_o^P \\theta - p_o^P - p_o^o$ if serviced by originator, $Q_c^P \\theta - p_c^P - p_c^c$ if serviced by contributor)</td>\n</tr>\n<tr>\n<td>$V^O(\\theta)$</td>\n<td>Net payoff to purchasing consumer with type $\\theta$ under open source strategy</td>\n</tr>\n<tr>\n<td></td>\n<td>($Q_o^O \\theta - p_o^O$ if serviced by originator, $Q_c^O \\theta - p_c^O$ if serviced by contributor)</td>\n</tr>\n</tbody>\n</table>\nLemma OS.1 For fixed $p^P$, $p_o^P$, $p_c^P$, $e_o^P$ and $e_c^P$,\n\n(i) If $Q_o^P = s_o^P e_o^P > Q_c^P = s_c^P e_c^P$, then the originator is the quality leader and the consumer market has the following characterization of regions:\n\nRegion I: If $p_o^P \\geq Q_o^P - p^P$ and $p_c^P \\geq Q_c^P - p^P$, then no consumer uses the software.\n\nRegion II: If $p_o^P < Q_o^P - p^P$ and $p_c^P \\geq \\frac{p_c^P(Q_c^P - Q_o^P)}{Q_c^P}$, then only the originator is active in the market, and\n\n(a) consumers with $\\theta \\in [0, \\frac{p_o^P+p_c^P}{Q_o^P}]$ do not use the software, and\n(b) consumers with $\\theta \\in (\\frac{p_o^P+p_c^P}{Q_o^P}, 1]$ purchase the software from the originator and contract with the originator for the services;\n\nRegion III: If $p_o^P < Q_o^P - p^P$ and $p_c^P - (Q_o^P - Q_c^P) \\leq p_c^P < \\frac{p_c^P Q_o^P - p^P (Q_o^P - Q_c^P)}{Q_c^P}$, then both the originator and the contributor are active in the service market, and\n\n(a) consumers with $\\theta \\in [0, \\frac{p_o^P+p_c^P}{Q_o^P}]$ do not use the software,\n(b) consumers with $\\theta \\in (\\frac{p_o^P+p_c^P}{Q_o^P}, \\frac{p_c^P}{Q_o^P - Q_c^P}]$ purchase the software from the originator and contract with the contributor for the services, and\n(c) consumers with $\\theta \\in (\\frac{p_c^P}{Q_o^P - Q_c^P}, 1]$ purchase the software from the originator and contract with the contributor for the services;\n\nRegion IV: If either $p_c^P < Q_c^P - p^P$ and $p_c^P < p_c^P - (Q_o^P - Q_c^P)$, or $p_o^P \\geq Q_o^P - p^P$ and $p_c^P < Q_c^P - p^P$, then only the contributor is active in the service market, and\n\n(a) consumers with $\\theta \\in [0, \\frac{p_o^P+p_c^P}{Q_c^P}]$ do not use the software, and\n(b) consumers with $\\theta \\in (\\frac{p_o^P+p_c^P}{Q_c^P}, 1]$ purchase the software from the originator and contract with the contributor for the services.\n\n(ii) If $Q_o^P < Q_c^P$, then the contributor is the quality leader and the consumer market has the same characterization as in part (i), except only for switching $Q_o^P$ and $Q_c^P$, and $p_o^P$ and $p_c^P$ in all the expressions.\n\n(iii) If $Q_o^P = Q_c^P$, then\n\n(a) If $p_o^P < p_c^P$, then consumers with $\\theta \\in [0, \\min\\{(p_o^P + p_c^P)/Q_o^P, 1\\}]$ do not use the software, and consumers with $\\theta \\in (\\min\\{(p_o^P + p_c^P)/Q_o^P, 1\\}, 1]$ purchase and contract with the originator.\n\n(b) If $p_o^P > p_c^P$, consumers with $\\theta \\in [0, \\min\\{(p_o^P + p_c^P)/Q_o^P, 1\\}]$ do not use the software, and consumers with $\\theta \\in (\\min\\{(p_o^P + p_c^P)/Q_o^P, 1\\}, 1]$ purchase from the originator and contract with the contributor for the services.\n\n(c) If $p_o^P = p_c^P$, the consumers with $\\theta \\in [0, \\min\\{(p_o^P + p_c^P)/Q_o^P, 1\\}]$ do not use the software, and consumers with $\\theta \\in (\\min\\{(p_o^P + p_c^P)/Q_o^P, 1\\}, 1]$ purchase from the originator and are indifferent between contracting with the two firms and randomly select a provider for the services.\nProof: For part (i), suppose $Q^P_o > Q^P_c$. By (1), a consumer with type $\\theta$,\n\n(a) prefers to contract with the originator for services and to purchase the source code from the originator rather than to not use the software if and only if $Q^P_o \\theta - p^P - p^P_o \\geq 0$, i.e., $\\theta \\geq \\theta^P_{oN}$, where $\\theta^P_{oN}$ is defined as $(p^P + p^P_o)/Q^P_o$;\n\n(b) prefers to contract with the contributor for services and to purchase the source code from the originator rather than to not use if and only if $Q^P_c \\theta - p^P - p^P_c \\geq 0$, i.e., $\\theta \\geq \\theta^P_{cN}$, where $\\theta^P_{cN}$ is defined as $(p^P + p^P_c)/Q^P_c$; and\n\n(c) prefers to contract with the originator rather than the contributor, for services after purchasing the source code from the originator if and only if $Q^P_o \\theta - p^P - p^P_o \\geq Q^P_c \\theta - p^P - p^P_c$, i.e., $\\theta \\geq \\theta^P_{oc} = (p^P - p^P_c)/(Q^P_o - Q^P_c)$.\n\nNow suppose $\\theta^P_{oN} = (p^P + p^P_o)/Q^P_o \\leq \\theta^P_{cN} = (p^P + p^P_c)/Q^P_c$, then by carrying out the algebra, it follows that $\\theta^P_{oc} = (p^P - p^P_c)/(Q^P_o - Q^P_c) \\leq \\theta^P_{oN} = (p^P + p^P_o)/Q^P_o \\leq \\theta^P_{cN} = (p^P + p^P_c)/Q^P_c$. In this case, all consumers who prefer to contract with the contributor for services and to purchase the software from the originator rather than to not use, i.e., consumers with $\\theta \\geq \\theta^P_{cN}$, prefer to contract with the originator for services rather than the contributor since for those consumers, $\\theta \\geq \\theta^P_{cN} \\geq \\theta^P_{oc}$. Thus, in this region, there are only two possible consumer choice outcomes: a consumer either purchases the software and contracts with the originator for the service or does not use the software. Consequently, if $\\theta^P_{oN} \\geq 1$, i.e., if $p^P_o \\geq Q^P_o - p^P$ then no consumer uses the software. Notice that in this case, if $p^P_o \\geq Q^P_o - p^P$, it also means that $p^P_c \\geq Q^P_c - p^P$, since $\\theta^P_{oN} = (p^P + p^P_o)/Q^P_o \\leq \\theta^P_{cN} = (p^P + p^P_c)/Q^P_c$. That is, in Region I, as defined in part (i), no consumer uses the software. On the other hand, if $\\theta^P_{oN} < 1$, i.e., if $p^P \\leq Q^P_o - p^P$, then consumers with types $\\theta \\in (\\theta^P_{oN}, 1]$ contract with the originator for services and purchase the software from the originator, and the rest, i.e., those with $\\theta \\in [0, \\theta^P_{oN}]$ do not use the software. Again notice that $(p^P + p^P_o)/Q^P_o \\leq (p^P + p^P_c)/Q^P_c$ implies $p^P_c \\geq (p^P_o Q^P_c - p^P(Q^P_o - Q^P_c))/Q^P_c$, i.e., Region II as defined above, therefore the statement for this region is also confirmed.\n\nNext, suppose that $\\theta^P_{oN} = (p^P + p^P_o)/Q^P_o \\geq \\theta^P_{cN} = (p^P + p^P_c)/Q^P_c$. Then we have $\\theta^P_{oc} = (p^P - p^P_c)/(Q^P_o - Q^P_c) \\geq \\theta^P_{oN} = (p^P + p^P_o)/Q^P_o \\geq \\theta^P_{cN} = (p^P + p^P_c)/Q^P_c$. Thus, in this case, if $\\theta \\leq \\theta^P_{oc} = (p^P_o - p^P_c)/(Q^P_o - Q^P_c)$, then a consumer with type $\\theta$ always prefers to contract with the contributor for the services given that she chooses to purchase the software. This means that if $\\theta^P_{oc} < 1$, then consumers with types $\\theta \\in (\\theta^P_{oc}, 1]$ contract with the originator for services after purchasing the software from the originator, consumers with types $\\theta \\in (\\theta^P_{cN}, \\theta^P_{oc})$ contract with the contributor for services after purchasing the software from the originator, and the rest with types $\\theta \\in [0, \\theta^P_{cN}]$ do not use the software. Notice that since $Q^P_o > Q^P_c$, $\\theta^P_{oc} < 1$ if and only if $p^P_o - (Q^P_o - Q^P_c) p^P_c$. Therefore, if $\\theta^P_{oN} = (p^P + p^P_o)/Q^P_o \\geq \\theta^P_{cN} = (p^P + p^P_c)/Q^P_c$, that is, if $p^P \\leq (p^P_o Q^P_c - p^P(Q^P_o - Q^P_c))/Q^P_c$, together with $p^P_o - (Q^P_o - Q^P_c) \\leq p^P_c$, i.e., in Region III, then the consumer market for services will be split as described in the statement of the lemma. Note that $p^P_o - (Q^P_o - Q^P_c) < (p^P_o Q^P_c - p^P(Q^P_o - Q^P_c))/Q^P_c$ implies that $p^P_o < Q^P_o - p^P$. On the other hand, if either $p^P_o < Q^P_o - p^P$ and $p^P_c \\leq p^P_o - (Q^P_o - Q^P_c)$, or $p^P_o \\geq Q^P_o - p^P$ and $p^P_c < Q^P_o - p^P$, i.e., in Region IV, then no consumer with type $\\theta \\in [0, 1]$ will prefer to contract with the originator over the contributor for services, and hence consumers with types $\\theta \\in (\\theta^P_{cN}, 1]$ contract with the contributor for services after purchasing the\nsoftware, and the rest with types $\\theta \\in [0, \\theta^P_{C, N}]$ do not use the software as stated. This proves part (i). Part (ii) follows in exactly similar manner except the originator and the contributor are switched.\n\nFor part (iii), when $Q_o^P = Q_c^P$, there is no product differentiation and, as in a standard Bertrand competition case for services, all consumers prefer the lower priced service if there is a difference in service prices. If the prices are the same, all consumers are indifferent and they choose between the two service providers randomly. This completes the proof. □\n\n**Proof of Proposition 1:** Technically, we will prove that, given $e_o^P$ and $e_c^P$,\n\n(i) If $Q_o^P = s_{oo}^P e_o^P > Q_c^P = (s_{co}^P e_o^P + s_{cc}^P e_c^P)$, then $p^o* = \\frac{s_{oo}^P e_o^P}{2}$, $p^o* = 0$, and $p_c^o = 0$;\n\n(ii) If $Q_o^P = s_{oo}^P e_o^P = Q_c^P = (s_{co}^P e_o^P + s_{cc}^P e_c^P)$, then $p^o* = (s_{oo}^P e_o^P + s_{co}^P e_o^P + s_{cc}^P e_c^P)^P$, $p_o^* = -\\frac{(s_{oo}^P e_o^P + s_{co}^P e_o^P + s_{cc}^P e_c^P)^P}{s_{oo}^P}$ and $p_c^o = \\frac{(s_{oo}^P + s_{co}^P + s_{cc}^P) e_o^P}{3} + s_{co}^P e_o^P$.\n\nWe focus on the case in which the originator is the quality leader, i.e., $Q_o^P = s_{oo}^P e_o^P > Q_c^P = (s_{co}^P e_o^P + s_{cc}^P e_c^P)\\). We start by writing the profit functions for the originator. Using Lemma OS.1, in the pricing stage, given the investment levels $e_o^P$ and $e_c^P$, the originator’s profit (excluding the effort investment costs) is given as follows (the indicated regions are as defined in part (i) of Lemma OS.1):\n\nIf $p_c^P \\geq Q_c^P$, then the contributor is squeezed out of the services market, and\n\n$$\n\\Pi_o^P(p_c^P, p_o^P | p_c^P, e_o^P, e_c^P) = \\begin{cases} \n(p^o + p_o^P) \\left(1 - \\frac{p^o + p_o^P}{Q_o^P}\\right) & \\text{if } p^o + p_o^P \\leq Q_o^P \\text{ (Region II)}; \\\\\n0 & \\text{if } p^o + p_o^P > Q_o^P \\text{ (Region I)}. \n\\end{cases}\n$$\n\nOn the other hand, if $p_c^P < Q_c^P$, then\n\n$$\n\\Pi_o^P(p_c^P, p_o^P | p_c^P, e_o^P, e_c^P) = \\begin{cases} \n(p^o + p_o^P) \\left(1 - \\frac{p^o + p_o^P}{Q_o^P}\\right) & \\text{if } p_o^P Q_o^P - p^o (Q_o^P - Q_c^P) \\leq Q_o^P p_c^P, \\text{ and } p_o^P \\leq p_c^P + Q_o^P - Q_c^P \\text{ (Region II)}; \\\\\np^o \\left(1 - \\frac{p^o + p_o^P}{Q_o^P}\\right) + p_o^P \\left(1 - \\frac{p^o + p_o^P}{Q_o^P}\\right) & \\text{if } p_o^P Q_o^P - p^o (Q_o^P - Q_c^P) > Q_o^P p_c^P, \\text{ and } p_o^P \\leq p_c^P - Q_c^P \\text{ (Region I)}; \\\\\np^o \\left(1 - \\frac{p^o + p_o^P}{Q_o^P}\\right) & \\text{if } p_o^P > p_c^P + Q_o^P - Q_c^P, \\text{ and } p_o^P \\leq Q_o^P - p_c^P \\text{ (Region IV)}; \\\\\n0 & \\text{if } p_o^P > Q_o^P - p_c^P, \\text{ and } p_o^P + p_c^P > Q_o^P \\text{ (Region I)}. \n\\end{cases}\n$$\n\nSimilarly, again using Lemma OS.1, the contributor’s profit (excluding the effort investment costs) is given as follows:\n\nIf $p_c^P \\geq Q_c^P$ or $Q_o^P p_o^P \\leq (Q_o^P - Q_c^P)p^o$, then the contributor is squeezed out of the market and\n\n$$\n\\Pi_c^P(p_c^P \\mid p_o^P, e_o^P, e_c^P) = 0 \\text{ (Regions I and II)}. \n$$\n\n\\[1\\]Note that in this case, there are multiple pricing equilibria; however, in all equilibria, the equilibrium profit outcomes are the same as those presented in this part of the proposition. Consequently, the resulting equilibrium outcomes for the effort investments are also the same. For clarity, here we choose to present the simplest equilibrium (which corresponds to zero service prices). The full set of equilibria are available from the authors upon request.\n\nOS.4\nHowever, if \\( p^P < Q_c^P \\), \\( Q_c^P p_o^P > (Q_o^P - Q_c^P) p^P \\) and \\( p^P + p_o^P \\geq Q_o^P \\), then the originator is squeezed out of the services market and\n\n\\[\n\\hat{\\Pi}_c(p_c^P \\mid p^P, p_o^P, e_o^P, e_c^P) = \\begin{cases} \n p_c^P \\left( 1 - \\frac{p^P + p_o^P}{s_{oo} e_o^P + s_{cc} e_c^P} \\right) & \\text{if } p_c^P \\leq s_{oo} e_o^P + s_{cc} e_c^P - p^P \\ (\\text{Region IV}); \\\\\n 0 & \\text{if } p_c^P > s_{oo} e_o^P + s_{cc} e_c^P - p^P \\ (\\text{Region I}). \n\\end{cases}\n\\] \n\n(OS.3)\n\nFinally, if \\( p^P < Q_c^P \\), \\( Q_c^P p_o^P > (Q_o^P - Q_c^P) p^P \\) and \\( p^P + p_o^P < Q_o^P \\), then\n\n\\[\n\\hat{\\Pi}_c(p_c^P \\mid p^P, p_o^P, e_o^P, e_c^P) = \\begin{cases} \n p_c^P \\left( 1 - \\frac{p^P + p_o^P}{s_{oo} e_o^P + s_{cc} e_c^P} \\right) & \\text{if } p_c^P \\leq p^P - ((s_{oo} e_o^P - s_{cc} e_c^P) / p_o^P) \\ (\\text{Region IV}); \\\\\n p_c^P \\left( \\frac{p^P - p_o^P}{s_{oo} e_o^P - s_{cc} e_c^P} \\right) & \\text{if } p_o^P - ((s_{oo} e_o^P - s_{cc} e_c^P) / p^P) < p_c^P \\\\\n 0 & \\text{if } p_c^P (s_{oo} e_o^P + s_{cc} e_c^P - p^P) - p_o^P ((s_{oo} e_o^P - s_{cc} e_c^P) / p^P) < p_c^P \\ (\\text{Region II}). \n\\end{cases}\n\\] \n\n(OS.4)\n\nNote that if the contributor is the quality leader, i.e., if \\( Q_c^P (= s_{oo} e_o^P + s_{cc} e_c^P) > Q_o^P (= s_{oo} e_o^P) \\), then the profit expressions will be similar with the originator’s quality and the contributor’s quality roles reversed.\n\nSuppose the originator is the quality leader, i.e., if \\( Q_o^P (= s_{oo} e_o^P) \\) \\( > Q_c^P \\). We first derive the originator’s best response function \\( B_o(p_c^P) = (p^P, p_o^P) \\) that gives her optimal software price, \\( p^P \\), and service price, \\( p_o^P \\), choices for any service price, \\( p_c^P \\), chosen by the contributor.\n\n1- If \\( p_c^P \\geq Q_c^P \\), the originator’s profit function is as given in (OS.1). Writing the first order conditions for \\( p_o^P \\) and \\( p^P \\) from this expression leads to the same equation:\n\n\\[\n1 - \\frac{2(p^P + p_o^P)}{Q_o^P} = 0.\n\\] \n\n(OS.5)\n\nNotice that the second order conditions are always satisfied. Further,\n\n\\[\nB_o(p_c^P) = (p^P, p_o^P) = \\left( \\frac{Q_o^P}{2}, 0 \\right) = \\left( \\frac{s_{oo} e_o^P}{2}, 0 \\right)\n\\] \n\n(OS.6)\n\nsatisfy the first order conditions. Thus we conclude that \\( (p^P, p_o^P) = (s_{oo} e_o^P /2, 0) \\) is the best response price pair for this case.\n\n2- If \\( p_c^P < Q_c^P \\), the originator’s profit function is given in equation (OS.2). As can be seen in that equation, there are three regions to consider:\n\n(a) If \\( p_c^P Q_c^P = p^P (Q_o^P - Q_c^P) \\leq Q_o^P p_c^P \\), and \\( p^P + p_o^P \\leq Q_o^P \\), then we are in Region II, so the profit function is identical to given in (OS.1) and the optimality conditions are as stated in the proof of case (1) above. Thus, \\( (p^P, p_o^P) = (Q_o^P /2, 0) \\) is the maximizer of the profit function. We only need to verify that this price pair falls into this region and hence it is the true optimizer in this region. For \\( (p^P, p_o^P) = (Q_o^P /2, 0) \\), \\( p_o^P Q_c^P = p^P (Q_o^P - Q_c^P) = -\\frac{Q_c^P}{2} (Q_o^P - Q_c^P) \\leq 0 \\leq Q_o^P p_c^P \\), and \\( p^P + p_o^P = Q_o^P /2 \\leq Q_o^P \\). It follows that \\( (p^P, p_o^P) = (s_{oo} e_o^P /2, 0) \\) is indeed a best response price pair\nfor this case.\n\n(b) If \\( p^P_o Q_c^P - p^P (Q_o^P - Q_c^P) > Q_o^P p_c^P \\), and \\( p^P_o \\leq p_c^P + Q_o^P - Q_c^P \\), then we are in Region III. The maximization problem in this region is separable in \\( p^P \\) and \\( p_o^P \\), and the profit function \\( \\hat{\\Pi}^P_o \\) is quadratic in both \\( p^P \\) and \\( p_o^P \\). Writing the first order conditions for \\( p_o^P \\) and \\( p^P \\), we obtain\n\n\\[\n1 - \\frac{2p^P + p_o^P}{Q_c^P} = 0 \\quad \\text{and} \\quad 1 - \\frac{2p_o^P - p_c^P}{Q_o^P - Q_c^P} = 0. \\quad \\text{(OS.7)}\n\\]\n\nBy solving these first order conditions and noticing that the second order conditions are always satisfied, we obtain the interior best response prices, if feasible, as \\( p^P = (Q_c^P - p_c^P)/2 \\) and \\( p_o^P = (Q_o^P - Q_c^P + p_c^P)/2 \\). However, at these interior best response prices, \\( p_o^P Q_c^P - p^P (Q_o^P - Q_c^P) = Q_o^P p_c^P/2 < Q_o^P p_c^P \\) holds, and hence, the interior best response prices do not satisfy the conditions for this region and fall outside of it. Therefore, the best response price pairs in this region fall on the boundaries of the region.\n\n(c) If \\( p^P > p_c^P + Q_o^P - Q_c^P \\), and \\( p^P \\leq Q_o^P - p_c^P \\), then we are in Region IV. In this region, as can be seen in (OS.2), the originator’s profit \\( \\hat{\\Pi}^P_o \\) is a concave quadratic function of only \\( p^P \\), and does not depend on \\( p_o^P \\). The first order condition is\n\n\\[\n1 - \\frac{2p^P + p_o^P}{Q_c^P} = 0 \\quad \\text{(OS.8)}\n\\]\n\nand the second order condition is always satisfied. Then, the interior best response price is \\( p^P = (Q_c^P - p_c^P)/2 \\), which always falls into the region, since \\( p^P \\leq Q_c^P - p_c^P \\). In this case, the corresponding originator’s profit is \\( \\hat{\\Pi}^P_o = (Q_o^P - p_c^P)^2/4Q_c^P \\).\n\nNow, consider the boundary of Regions II and III. This boundary is defined by the line \\( p_o^P Q_c^P - p^P (Q_o^P - Q_c^P) = Q_o^P p_c^P \\), which is equivalent to\n\n\\[\n\\frac{p^P + p_o^P}{Q_c^P} = \\frac{p^P + p_c^P}{Q_c^P} = \\frac{p_o^P - p_c^P}{Q_o^P - Q_c^P}. \\quad \\text{(OS.9)}\n\\]\n\nPlugging this into the profit functions for Regions II and III given in (OS.2), we see that both profit expressions on this boundary are equal to\n\n\\[\n\\frac{Q_o^P (p_o^P - p_c^P)}{Q_o^P - Q_c^P} \\left( 1 - \\frac{p_o^P - p_c^P}{Q_o^P - Q_c^P} \\right). \\quad \\text{(OS.10)}\n\\]\n\nThat is, the originator’s profit function is continuous on this boundary. Similarly, consider the boundary of Regions III and IV. This boundary is defined by the line \\( p_o^P = p_c^P + Q_o^P - Q_c^P \\), which is equivalent to \\((p_o^P - p_c^P)/(Q_o^P - Q_c^P) = 1\\). Plugging this into the profit functions for Regions III and IV given in (OS.2), we obtain both profit expressions on this boundary as\n\n\\[\np^P \\left( 1 - \\frac{p_o^P + p_c^P}{Q_c^P} \\right). \\quad \\text{(OS.11)}\n\\]\nConsequently, the originator’s profit function in (OS.2) is continuous in \\( p^P \\) and \\( p^P_o \\). Since in Regions II and IV the maximum profit is attained at interior points, the maximum values of these peaks are higher than those of the boundary points of these regions with Region III. But as we mentioned above, Region III maximum is attained at its boundaries. Therefore, since the profit function is continuous, the maximum in Region III is dominated by the maxima of Regions II and IV. In summary, the originator’s profit function as described in (OS.2) is maximized at the interior peak of either Region II or Region IV, and the overall maximum can be found by comparing these two. By plugging in the interior maximum best response price pairs found for Regions II and IV above, the corresponding maximum profit levels in Regions II and IV are \\( Q^P_o/4 \\) and \\( (Q^P_o - p^P_c)^2/4Q^P_c \\), respectively. Since \\( Q^P_o > Q^P_c \\), \\( Q^P_o/4 \\geq (Q^P_o - p^P_c)^2/4Q^P_c \\). Therefore, the optimal price pair for the originator falls into Region II and the best response prices are given as in (OS.6).\n\nNext, we derive the contributor’s best response function \\( B_c(p^P, p^P_o) = p^P_c \\) that gives his optimal service price \\( p^P_c \\) choice for any given software price \\( p^P \\) and service price \\( p^P_o \\) chosen by the originator.\n\n1- If \\( p^P \\geq Q^P_c \\) or \\( Q^P_o p^P_o \\leq (Q^P_o - Q^P_c)p^P \\), then the contributor is squeezed out of the market and his profit equals zero for any non-negative service price \\( p^P_c \\). Consequently, \\( B_c(p^P, p^P_o) \\) is any non-negative service price \\( p^P_c \\).\n\n2- If \\( p^P < Q^P_c \\) and \\( p^P + p^P_o \\geq Q^P_o \\), then the contributor’s profit function is as given in (OS.3). Writing the first order condition for \\( p^P_c \\) corresponding to Region IV gives\n\n\\[\n1 - \\frac{p^P + 2p^P}{s^P_c e^P_c + s^P_c e^P_c} = 0\n\\] \n(OS.12)\n\nand the second order condition is always satisfied. Solving the first order condition, we obtain the optimal service price for the contributor, which is \\( (s^P_c e^P_o + s^P_c e^P_c - p^P)/2 \\). Note that it falls into the interior of Region IV, since the condition \\( p^P_c \\leq s^P_c e^P_o + s^P_c e^P_c - p^P \\) is satisfied. Therefore, in this case, \\( B_c(p^P, p^P_o) = (s^P_c e^P_o + s^P_c e^P_c - p^P)/2 \\).\n\n3- If \\( p^P < Q^P_c \\), \\( Q^P_o p^P_o > (Q^P_o - Q^P_c)p^P \\) and \\( p^P + p^P_o < Q^P_o \\), then the contributor’s profit function is given in equation (OS.4). As can be seen in that equation, there are two regions to consider:\n\n(a) If \\( p^P_c \\leq p^P_o - (Q^P_o - Q^P_c) \\), then we are in Region IV, so the profit function is identical to given in (OS.3) and the optimality conditions are as stated in the proof of case (2). Thus, \\( p^P_c = (s^P_c e^P_o + s^P_c e^P_c - p^P)/2 \\), if falls into this region, is the maximizer of the profit function in this region. Note that the condition for this region, i.e., \\( p^P_c \\leq p^P_o - (Q^P_o - Q^P_c) \\), is satisfied at this interior maximizer if and only if \\( 2p^P_o + p^P \\geq 2Q^P_o - Q^P_c \\). In that case, the best response price is \\( B_c(p^P, p^P_o) = (s^P_c e^P_o + s^P_c e^P_c - p^P)/2 \\) and the corresponding profit is \\( (Q^P_c - p^P)^2/4Q^P_c \\). Otherwise, i.e., if \\( 2p^P_o + p^P < 2Q^P_o - Q^P_c \\), then the profit function is increasing in \\( p^P_c \\) and the best response price in this region is at the upper boundary of the region, i.e., \\( B_c(p^P, p^P_o) = p^P_o - ((s^P_o - s^P_c) e^P_o - s^P_c e^P_c) \\).\n\n(b) If \\( p^P_o - ((s^P_o - s^P_c) e^P_o - s^P_c e^P_c) < p^P_c \\leq (p^P_o (s^P_c e^P_o + s^P_c e^P_c) - p^P (s^P_o - s^P_c) e^P_o - s^P_c e^P_c))/s^P_o e^P_c \\), then we are in Region III. In this region, the profit function, as can be seen in (OS.4) is strictly concave.\nand quadratic in $p_c^P$. Its first order condition is\n\n$$\\frac{p_c^P - 2p_o^P}{(s_{co}^o - s_{co}^P)e^P_c - s_{cc}^c e^P_c} - \\frac{p^P + 2p_c^P}{s_{co}^o e^P_c + s_{cc}^c e^P_c} = 0,$$\n\n(OS.13)\n\nand the second order condition is always satisfied. Solving the first order condition, we obtain that the interior optimizer, it falls into this region, is given by $p_c^P = ((s_{co}^o e^P_o + s_{cc}^c e^P_o)p_o^P - (s_{co}^o - s_{co}^P)e^P_o - s_{cc}^c e^P_o)p^P) / 2s_{co}^o e^P_o$. Note that at this interior optimizer price $p_c^P$, the condition $p_c^P - (s_{co}^o - s_{co}^P)e^P_o - s_{cc}^c e^P_o < p^P < (s_{co}^o e^P_o + s_{cc}^c e^P_o) - p^P((s_{co}^o - s_{co}^P)e^P_o - s_{cc}^c e^P_o) / s_{co}^o e^P_o$ is satisfied if and only if $(2Q_o^P - Q_c^P)p_o^P + (Q_o^P - Q_c^P)p^P < 2Q_o^P(Q_o^P - Q_c^P)$ is satisfied. In that case, the best response price is $B_c(p^P, p_o^P) = ((s_{co}^o e^P_o + s_{cc}^c e^P_o)p_o^P - (s_{co}^o - s_{co}^P)e^P_o - s_{cc}^c e^P_o)p^P) / 2s_{co}^o e^P_o$ and the corresponding profit is $(Q_o^P - Q_c^P)p_o^P + (Q_o^P - Q_c^P)p^P \\geq 2Q_o^P(Q_o^P - Q_c^P)$, then the profit function is decreasing in $p_c^P$ and the best response price in this region falls on the lower boundary of the region, i.e., $B_c(p^P, p_o^P) = p_o^P - ((s_{co}^o - s_{co}^P)e^P_o - s_{cc}^c e^P_o)$.\n\nIn order to find the overall maximizer of the profit function, we need to compare the maximums in these two regions. There are four subcases:\n\nFirst, if $2p_o^P + p^P \\geq 2Q_o^P - Q_c^P$ and $(2Q_o^P - Q_c^P)p_o^P + (Q_o^P - Q_c^P)p^P \\geq 2Q_o^P(Q_o^P - Q_c^P)$, then the interior optimizer exists only in Region IV. In Region III, the maximizer is on the boundary. In addition, the boundary condition $p_c^P = p_o^P - (s_{co}^o - s_{co}^P)e^P_o - s_{cc}^c e^P_o$ is equivalent to $\\frac{p_o^P - p_c^P}{(s_{co}^o - s_{co}^P)e^P_o - s_{cc}^c e^P_o} = 1$, and hence, the contributor’s profit function is continuous in $p_c^P$ at this boundary. As a result, the best response price in this case is $B_c(p^P, p_o^P) = (Q_o^P - p^P) / 2$.\n\nSecond, suppose $2p_o^P + p^P \\geq 2Q_o^P - Q_c^P$ and $(2Q_o^P - Q_c^P)p_o^P + (Q_o^P - Q_c^P)p^P < 2Q_o^P(Q_o^P - Q_c^P)$ are both satisfied. In this case, the interior optimizers exist for both Regions III and IV. However, in the relevant region of $p_o^P + p^P < 2Q_o^P - Q_c^P$ holds then\n\n$$(2Q_o^P - Q_c^P)p_o^P + (Q_o^P - Q_c^P)p^P = Q_o^P(2p_o^P + p^P) - Q_c^P(p_o^P + p^P) > Q_o^P(2Q_o^P - Q_c^P) - Q_c^P(p_o^P + p^P) = 2Q_o^P(Q_o^P - Q_c^P) + Q_c^P(Q_o^P - p_o^P - p^P) > 2Q_o^P(Q_o^P - Q_c^P).$$\n\n(OS.14)\n\nHence, it cannot be the case that Regions III and IV both have interior optimia.\n\nThird, if $2p_o^P + p^P < 2Q_o^P - Q_c^P$ and $(2Q_o^P - Q_c^P)p_o^P + (Q_o^P - Q_c^P)p^P \\geq 2Q_o^P(Q_o^P - Q_c^P)$, then neither Region III nor IV have interior optimizer. We have shown above that if there is no interior optimum, then profit is increasing in Region IV and decreasing in Region III. It then follows that the profit is maximized at the boundary point of these two regions, i.e., the best response price is $B_c(p^P, p_o^P) = p_o^P - (Q_o^P - Q_c^P)$.\n\nFourth and finally, if $2p_o^P + p^P < 2Q_o^P - Q_c^P$ and $(2Q_o^P - Q_c^P)p_o^P + (Q_o^P - Q_c^P)p^P < 2Q_o^P(Q_o^P - Q_c^P)$, then Region III has an interior optimum and Region IV does not, and as we showed above, the profit is increasing in Region IV. Further, as we also showed above, the contributor’s profit function is continuous in $p_c^P$, and hence, the best response price is the interior optimizer of Region III, i.e., $B_c(p^P, p_o^P) = (Q_o^P p_o^P - (Q_o^P - Q_c^P)p^P) / (2Q_o^P)$. OS.8\nIn summary we obtain the contributor’s best response function as\n\n\\[\nB_c(p^P, p_o^P) = \\begin{cases} \n \\frac{Q_o^P - p_o^P}{2}, & \\text{if } 2p_o^P + p^P \\geq 2Q_o^P - Q_c^P; \\\\\n p^P - (Q_o^P - Q_c^P), & \\text{if } 2p_o^P + p^P < 2Q_o^P - Q_c^P \\text{ and } (2Q_o^P - Q_c^P)p_o^P + (Q_o^P - Q_c^P)p^P \\geq 2Q_o^P(Q_o^P - Q_c^P); \\\\\n \\frac{2Q_o^P - (Q_c^P - Q_o^P)p^P}{2Q_o^P}, & \\text{if } (2Q_o^P - Q_c^P)p_o^P + (Q_o^P - Q_c^P)p^P < 2Q_o^P(Q_o^P - Q_c^P). \n\\end{cases} \n\\]\n\n(OS.15)\n\nThe Nash Equilibrium prices can then be found by simultaneously solving the best response functions\n\n\\[\nB_c(p^{P*}, p_o^{P*}) = p^{P*} \\text{ and } B_o(p_c^{P*}) = (p^{P*}, p_o^{P*}).\n\\]\n\n(OS.16)\n\nSince, \\( p^P = Q_o^P/2 \\) and \\( p_o^P = 0 \\). Therefore, Case 1 for the contributor’s best response function applies. In this case, the contributor is out of the services market at any non-negative price he sets. Therefore, for any \\( \\psi \\geq 0 \\), \\((p^{P*}, p_o^{P*}, p_c^{P*}) = (Q_o^P/2, 0, \\psi)\\) is an equilibrium profile. In the simplest case where \\( \\psi = 0 \\), which gives us the equilibrium as stated. This completes the proof of part (i).\n\nOn the other hand, if the contributor is the quality leader, the originator’s profit function (excluding the investment cost) can be written as\n\n\\[\n\\Pi_o(p^P, p_o^P | p_c^P, e_o^P, e_c^P) = \\begin{cases} \n (p^P + p_o^P) \\left( 1 - \\frac{p^P + p_o^P}{s_{oo}e_o^P} \\right) & \\text{if } p^P + p_o^P \\leq s_{oo}e_o^P, \\text{ and } p_o^P \\leq p_c^P; \\\\\n p^P \\left( 1 - \\frac{p^P + p_o^P}{s_{cc}e_c^P + s_{co}e_o^P} \\right) & \\text{if } p^P \\leq s_{co}e_o^P + s_{cc}e_c^P - p_c^P, \\text{ and } p_o^P \\geq p_c^P; \\\\\n 0 & \\text{if } p^P + p_o^P > s_{oo}e_o^P, \\text{ and } p^P > s_{co}e_o^P + s_{cc}e_c^P - p_c^P.\n\\end{cases}\n\\]\n\n(OS.17)\n\nand the contributor’s profit function (again excluding the effort investment cost) can be written as\n\n\\[\n\\Pi_c(p_c^P | p^P, p_o^P, e_o^P, e_c^P) = \\begin{cases} \n p_c^P \\left( 1 - \\frac{p^P + p_o^P}{s_{oo}e_o^P + s_{cc}e_c^P} \\right) & \\text{if } p_c^P \\leq s_{co}e_o^P + s_{cc}e_c^P - p_c^P, \\text{ and } p_o^P \\leq p_c^P; \\\\\n 0 & \\text{if } p_c^P > s_{oo}e_o^P + s_{cc}e_c^P - p_c^P, \\text{ or } p_o^P > p_c^P.\n\\end{cases}\n\\]\n\n(OS.18)\n\nFollowing similar steps as in part (i) and using (OS.17) and (OS.18), we can also obtain the equilibrium result presented in part (ii) for the case when the contributor is the quality leader, i.e., \\( Q_c^P = s_{oo}e_o^P \\leq Q_o^P = s_{oo}e_o^P + s_{cc}e_c^P \\). The details are omitted here because they are repetitive of the proof of part (i) given above.\n\n\\[\\blacksquare\\]\n\n**Proof of Proposition 2:** Technically, given \\( e_o^P \\geq 0 \\), the contributor’s profit function can be written as\n\n\\[\n\\Pi_c(e_c^P | e_o^P) = \\begin{cases} \n -\\frac{\\beta_c}{2} (e_c^P)^2 & \\text{if } e_c^P \\leq \\frac{s_{co}e_o^P}{s_{ee}} e_o^P; \\\\\n \\frac{s_{ee}e_c^P - (s_{co}e_o^P e_c^P)}{y} - \\frac{\\beta_c}{2} (e_c^P)^2 & \\text{if } e_c^P > \\frac{s_{co}e_o^P}{s_{ee}} e_o^P.\n\\end{cases}\n\\]\n\n(OS.19)\n\nWe will prove that, given \\( e_o^P \\geq 0 \\) and denoting \\( e_c^{P*}(e_o^P) \\) as the solution to maximizing (OS.19),\n\n(i) If \\( e_o^P < \\bar{e}_o \\), then \\( e_c^{P*}(e_o^P) = \\frac{s_{oo}e_o^P}{s_{ee}} \\) and \\( Q_c^P > Q_o^P \\);\n(ii) If \\( e_o^P \\geq \\bar{e}_o \\), then \\( e_c^P/e_o^P = 0 \\), where \\( \\bar{e}_o = (s_{cc}^P)^2/(18\\beta_c(s_{oo}^P - s_{co}^P)) \\). From the contributor’s profit given in (OS.19), first, in the region of \\( e_c^P \\leq (s_{oo}^P - s_{co}^P)e_o^P/s_{cc}^P \\), the contributor’s optimal effort \\( e_c^P \\) is zero with zero as the corresponding profit. In the alternative region where \\( e_c^P \\geq (s_{oo}^P - s_{co}^P)e_o^P/s_{cc}^P \\), the effort level that satisfies the first order condition is \\( s_{cc}^P/9\\beta_c \\), which falls in the region if and only if \\( e_o^P < \\frac{(s_{cc}^P)^2}{9\\beta_c(s_{oo}^P - s_{co}^P)} \\). Moreover, at this effort level, the contributor’s corresponding profit is \\( \\frac{(s_{cc}^P)^2}{108\\beta_c} - \\frac{(s_{oo}^P - s_{co}^P)\\beta_c e_o^P}{9} \\), which is positive if and only if \\( e_o^P < \\bar{e}_o \\). If \\( e_o^P \\geq \\frac{(s_{cc}^P)^2}{9\\beta_c(s_{oo}^P - s_{co}^P)} \\), then the contributor’s profit is strictly increasing on \\( e_c^P \\geq \\frac{s_{oo}^P - s_{co}^P}{s_{cc}^P} e_o^P \\). Finally, note that at \\( e_c^P = \\frac{(s_{oo}^P - s_{co}^P)}{s_{cc}^P} e_o^P \\), both profit expressions become identical to \\( -\\frac{\\beta_c(s_{oo}^P - s_{co}^P)^2(e_o^P)^2}{2(18\\beta_c)^2} \\), and hence, the contributor’s profit is continuous. Now, since, if \\( e_o^P < \\bar{e}_o \\), then \\( e_o^P < \\frac{(s_{cc}^P)^2}{9\\beta_c(s_{oo}^P - s_{co}^P)} \\), we have that, given \\( e_o^P < \\bar{e}_o \\), the maximizer for \\( e_c^P \\geq \\frac{s_{oo}^P - s_{co}^P}{s_{cc}^P} e_o^P \\) is \\( s_{cc}^P/9\\beta_c \\) and the corresponding profit is positive. The optimal profit for \\( e_c^P \\leq \\frac{s_{oo}^P - s_{co}^P}{s_{cc}^P} e_o^P \\) is zero, and hence the overall maximizer of the contributor’s profit is \\( e_c^P/e_o^P = s_{cc}^P/9\\beta_c \\). Further, from (OS.19), since \\( e_c^P/e_o^P \\geq \\frac{s_{oo}^P - s_{co}^P}{s_{cc}^P} e_o^P \\), the contributor is the quality leader. This proves part (i). On the other hand, if \\( e_o^P \\geq \\bar{e}_o \\) the maximum value for the curve \\( s_{oo}^P - s_{co}^P e_o^P - \\frac{\\beta_c}{2} \\) is negative. This means that the profit in the entire region \\( e_c^P \\geq \\frac{s_{oo}^P - s_{co}^P}{s_{cc}^P} e_o^P \\) is negative, while the maximum profit in the region \\( e_c^P < \\frac{s_{oo}^P - s_{co}^P}{s_{cc}^P} e_o^P \\) is zero which is attained at zero. Hence for this case, the overall profit maximizer for the contributor is \\( e_c^P/e_o^P = 0 \\), i.e., the contributor does not invest in the software and is out of the market. This completes the proof.\n\nProofs of Propositions 3 and 4: The originator’s profit function can be written as\n\n\\[\n\\Pi_0(e_o^P) = \\begin{cases} \n\\frac{4s_{oo}^P + 5s_{co}^P}{36}e_o^P - \\frac{\\beta_c}{2}(e_o^P)^2 + \\frac{(s_{cc}^P)^2}{81\\beta_c} & \\text{if } e_o^P \\leq \\bar{e}_o; \\\\\n\\frac{s_{oo}^P - s_{co}^P}{4}e_o^P - \\frac{\\beta_c}{2}(e_o^P)^2 & \\text{if } e_o^P > \\bar{e}_o,\n\\end{cases}\n\\tag{OS.20}\n\\]\n\nwhere \\( \\bar{e}_o \\) is as given in Proposition 2. Also, define\n\n\\[\n\\bar{r} = \\frac{2(s_{cc}^P)^2\\beta_o}{81(s_{oo}^P - s_{co}^P)(s_{co}^P)^2} \\left( 13s_{oo}^P - 4s_{co}^P + 2\\sqrt{2(s_{oo}^P - s_{co}^P)(11s_{oo}^P - 2s_{co}^P)} \\right).\n\\tag{OS.21}\n\\]\n\nTechnically, we will first prove that (i) if \\( \\beta_c < \\bar{r} \\), then \\( e_o^P = \\frac{5s_{oo}^P - 9s_{co}^P}{36\\beta_o} \\); and (ii) if \\( \\beta_c \\geq \\bar{r} \\), then \\( e_o^P = \\frac{s_{co}^P}{4\\beta_o} \\).\n\nPart (i) corresponds to the determination of originator effort level in the statement of Proposition 3, and part (ii) corresponds to the same for Proposition 4.\n\nFirst suppose that \\( e_o^P \\leq \\frac{(s_{cc}^P)^2}{18\\beta_c(s_{oo}^P - s_{co}^P)} \\). From (OS.20), the originator’s profit function in this region is\n\n\\[\n\\frac{4s_{oo}^P + 5s_{co}^P}{36}e_o^P - \\frac{\\beta_c}{2}(e_o^P)^2 + \\frac{(s_{cc}^P)^2}{81\\beta_c},\n\\]\n\nwhich is concave and quadratic in \\( e_o^P \\). So by solving the first order condition, we find that this curve is maximized at \\( e_o^P = \\frac{5s_{oo}^P + 4s_{co}^P}{36\\beta_o} \\), and the corresponding originator’s profit at this maximizer is\n\n\\[\n\\frac{(5s_{oo}^P + 4s_{co}^P)^2}{2592\\beta_o} + \\frac{(s_{cc}^P)^2}{81\\beta_c}.\n\\tag{OS.22}\n\\]\n\nNow, by carrying out the algebra, \\( \\frac{5s_{oo}^P + 4s_{co}^P}{36\\beta_o} \\leq \\frac{(s_{cc}^P)^2}{18\\beta_c(s_{oo}^P - s_{co}^P)} \\), i.e., the maximizer falls in the region where the first curve in (OS.20) is valid if and only if \\( \\beta_c < \\frac{(s_{oo}^P - s_{co}^P)(5s_{oo}^P + 4s_{co}^P)}{2(s_{cc}^P)^2\\beta_c} \\). Since the maximizer is positive, if it does not fall in the valid region, then the originator’s profit in this region, which is a quadratic, is increasing\nin $e_o^P$, and hence, the maximizer within $[0, \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}]$ is the upper boundary, i.e., $e_o^P = \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$, and the corresponding originator’s profit is\n\n$$\\frac{(s_P^o)^2}{648\\beta_c(s_{oo}^o - s_{co}^o)} \\left( 4s_P^c + 5s_{oo}^o - \\frac{\\beta_o(s_P^o)^2}{\\beta_c(s_{oo}^o - s_{co}^o)} \\right) + \\frac{(s_P^o)^2}{81\\beta_c}. \\quad (OS.23)$$\n\nNow consider the case $e_o^P \\geq \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$. Again from (OS.20), the originator’s profit function in this region is $\\frac{s_P^o e_o^P}{4} - \\frac{\\beta_e(s_P^o)^2}{2}$, which is also concave and quadratic in $e_o^P$. Therefore, by solving the first order condition, we obtain the maximizer of this curve as $e_o^P = \\frac{s_P^o}{4\\beta_e}$, with a corresponding profit of $\\frac{(s_P^o)^2}{32\\beta_e}$. Again carrying out the algebra, this maximizer falls in the region $e_o^P \\geq \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$ if and only if $\\beta_e \\geq \\frac{2(s_P^o)^2\\beta_o}{9\\beta_o(s_{oo}^o - s_{co}^o)}$.\n\nIf the maximizer is not in this region, i.e., if $\\beta_e \\leq \\frac{2(s_P^o)^2\\beta_o}{9\\beta_o(s_{oo}^o - s_{co}^o)}$, then the originator’s profit in this region is decreasing in $e_o^P$; hence, the maximizer on $e_o^P \\geq \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$ is the lower boundary, i.e., $e_o^P = \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$, at which point, the corresponding originator’s profit is\n\n$$\\frac{(s_P^o)^2}{36\\beta_c(s_{oo}^o - s_{co}^o)} \\left( \\frac{s_{oo}^o}{2} - \\frac{\\beta_o(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)} \\right). \\quad (OS.24)$$\n\nIn order to find the global optimizer for the originator’s profit function, we need to compare the maximums in these two regions as we derived above. First, notice that since $s_{oo}^o > s_{co}^o$, we have $\\frac{2(s_P^o)^2\\beta_o}{9\\beta_o(s_{oo}^o - s_{co}^o)} < \\frac{2(s_P^o)^2\\beta_o}{9\\beta_o(s_{oo}^o - s_{co}^o)e_o^P + 4s_P^o e_o^P}$. Then we have three cases for $\\beta_e$ to consider:\n\n(a) $\\beta_e < \\frac{2(s_P^o)^2\\beta_o}{9\\beta_o(s_{oo}^o - s_{co}^o)}$: In this case, the originator’s profit has an interior maximum on $e_o^P \\leq \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$, and is maximized at the lower boundary on $e_o^P > \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$. The corresponding profits are given in (OS.22) and (OS.24) as we have shown above. Subtracting the latter from the former we have\n\n$$\\frac{(5s_{oo}^o + 4s_{co}^o)^2}{2592\\beta_o} + \\frac{(s_P^o)^2}{81\\beta_c} - \\frac{(s_P^o)^2}{36\\beta_c(s_{oo}^o - s_{co}^o)} \\left( \\frac{s_{oo}^o}{2} - \\frac{\\beta_o(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)} \\right)$$\n\n$$= \\frac{(5s_{oo}^o + 4s_{co}^o)^2}{2592\\beta_o^2\\beta_c^2} \\left( \\beta_e - \\frac{2(s_P^o)^2(s_{oo}^o + 8s_{co}^o)\\beta_o}{(5s_{oo}^o + 4s_{co}^o)^2(s_{oo}^o - s_{co}^o)} \\right)^2 + \\frac{(s_P^o)^4(s_{oo}^o + 2s_{co}^o)\\beta_o}{27\\beta_o^2(s_{oo}^o - s_{co}^o)(5s_{oo}^o + 4s_{co}^o)^2} > 0, \\quad (OS.25)$$\n\nsince $s_{oo}^o > s_{co}^o$. Therefore, (OS.25) is strictly positive, and hence, the originator’s profit in (OS.22) is larger than that in (OS.24), i.e., the global maximizer is again the maximizer of the region $e_o^P \\leq \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$, which is $e_o^P = \\frac{5s_{oo}^o + 4s_{co}^o}{36\\beta_o}$. Finally, again as above, in equilibrium, the contributor will be active and will be the quality leader.\n\n(b) $\\frac{2(s_P^o)^2\\beta_o}{9\\beta_o(s_{oo}^o - s_{co}^o)} < \\beta_e < \\frac{2(s_P^o)^2\\beta_o}{9\\beta_o(s_{oo}^o - s_{co}^o)e_o^P + 4s_P^o e_o^P}$: In this case, the originator’s profit has an interior maximum both on $e_o^P \\leq \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$ and $e_o^P > \\frac{(s_P^o)^2}{18\\beta_c(s_{oo}^o - s_{co}^o)}$. As we have derived above, the maximum profit on the first region is given in (OS.22) and on the second region is $\\frac{(s_P^o)^2}{32\\beta_o}$. Now subtracting the latter from\nthe former, we obtain\n\n\\[\n\\frac{(5s_{oo}^2 + 4s_{co}^2)^2}{2592\\beta_o^2} + \\frac{(s_{co}^2)^2}{81\\beta_o^2} - \\frac{(s_{oo}^2)^2}{32\\beta_o^2} = \\frac{1}{\\beta_o} \\left( \\frac{\\beta_o (5s_{oo}^2 + 4s_{co}^2)^2}{2592} - \\frac{(s_{oo}^2)^2}{32} + \\frac{(s_{co}^2)^2}{81} \\beta_o \\right)\n\\]\n\n\\[\n> \\frac{1}{\\beta_o} \\left( \\frac{(5s_{oo}^2 + 4s_{co}^2)^2}{2592} - \\frac{(s_{oo}^2)^2}{32} + \\frac{(s_{co}^2)^2}{81} \\cdot \\frac{(s_{oo}^2 - s_{co}^2)(5s_{oo}^2 + 4s_{co}^2)}{2(s_{co}^2)^2} \\right) = \\frac{(s_{oo}^2 - s_{co}^2)(s_{co}^2 + 2s_{oo}^2)}{108\\beta_o} > 0,\n\\]\n\n(OS.26)\n\nsince \\( s_{oo}^2 > s_{co}^2 \\). Therefore, the originator’s maximum profit on the region \\( e_o^p \\leq \\frac{(s_{co}^2)^2}{18\\beta_o(s_{oo}^2 - s_{co}^2)} \\) is greater than that on \\( e_o^p > \\frac{(s_{co}^2)^2}{18\\beta_o(s_{oo}^2 - s_{co}^2)} \\) and the global maximizer in this case is \\( e_o^p = \\frac{5s_{oo}^2 + 4s_{co}^2}{9\\beta_o} \\), and as above, in equilibrium, the contributor will be active and will have higher quality.\n\n(c) \\( \\frac{2(s_{co}^2)^2\\beta_o}{(s_{oo}^2 - s_{co}^2)(5s_{oo}^2 + 4s_{co}^2)} \\leq \\beta_c \\): In this case, the originator’s profit is monotonically increasing in \\( e_o^p \\) on \\( e_o^p \\leq \\frac{(s_{co}^2)^2}{18\\beta_o(s_{oo}^2 - s_{co}^2)} \\) and has an interior maximum on \\( e_o^p > \\frac{(s_{co}^2)^2}{18\\beta_o(s_{oo}^2 - s_{co}^2)} \\). As we have derived above, the maximum profit on the first region is given in (OS.23) and on the second region is \\( \\frac{(s_{co}^2)^2}{32\\beta_o} \\). Now subtracting the former from the latter, we obtain\n\n\\[\n\\frac{(s_{oo}^2)^2}{32\\beta_o} - \\left( \\frac{(s_{cc}^2)^2}{648\\beta_c(s_{oo}^2 - s_{co}^2)} \\left( 4s_{co}^2 + 5s_{oo}^2 - \\frac{\\beta_o(s_{cc}^2)^2}{\\beta_c(s_{oo}^2 - s_{co}^2)} \\right) + \\frac{(s_{co}^2)^2}{81\\beta_o} \\right)\n\\]\n\n\\[\n= \\frac{4(s_{cc}^4\\beta_o^2 - 4(s_{cc}^2)^2(s_{oo}^2 - s_{co}^2)(13s_{oo}^2 - 4s_{co}^2))\\beta_o^2 + 81(s_{oo}^2 - s_{co}^2)^2(s_{cc}^2)^2\\beta_c^2}{2592\\beta_o^2\\beta_c^2(s_{oo}^2 - s_{co}^2)^2}.\n\\]\n\n(OS.27)\n\nThe denominator in (OS.27) is strictly positive and the numerator in (OS.27) is convex and quadratic in \\( \\beta_c \\). Furthermore, if we take the derivative of the numerator with respect to \\( \\beta_c \\), we obtain\n\n\\[\n162(s_{oo}^2 - s_{co}^2)^2(s_{co}^2)^2\\beta_c - 4(s_{cc}^2)^2(s_{oo}^2 - s_{co}^2)(13s_{oo}^2 - 4s_{co}^2)\\beta_o\n\\]\n\n\\[\n> 162(s_{oo}^2 - s_{co}^2)^2(s_{co}^2)^2 \\cdot \\frac{2(s_{co}^2)^2\\beta_o}{(s_{oo}^2 - s_{co}^2)(5s_{oo}^2 + 4s_{co}^2)} - 4(s_{cc}^2)^2(s_{oo}^2 - s_{co}^2)(13s_{oo}^2 - 4s_{co}^2)\\beta_o\n\\]\n\n\\[\n= \\frac{64(s_{cc}^2)^2(s_{oo}^2 - s_{co}^2)^3\\beta_o}{5s_{oo}^2 + 4s_{co}^2} > 0.\n\\]\n\n(OS.28)\n\nThat is, the numerator of (OS.27) is strictly increasing in \\( \\beta_c \\). In addition, the numerator becomes strictly positive as \\( \\beta_c \\to \\infty \\), and equals \\(-24(s_{oo}^2 - s_{co}^2)^2((s_{oo}^2)^2 - (s_{co}^2)^2)(s_{oo}^2 - s_{co}^2)^2) < 0 \\) at \\( \\beta_c = \\frac{2(s_{co}^2)^2\\beta_o}{(s_{oo}^2 - s_{co}^2)(5s_{oo}^2 + 4s_{co}^2)} \\). In summary, it starts negative and crosses to positive exactly once on \\( \\beta_c > \\frac{2(s_{co}^2)^2\\beta_o}{(s_{oo}^2 - s_{co}^2)(5s_{oo}^2 + 4s_{co}^2)} \\). Therefore, there exists the unique solution \\( \\bar{\\beta} \\geq \\frac{2(s_{co}^2)^2\\beta_o}{(s_{oo}^2 - s_{co}^2)(5s_{oo}^2 + 4s_{co}^2)} \\), which is the larger root of the quadratic equation of \\( \\beta_c \\) in the numerator of (OS.27), given in (OS.21), such that if \\( \\beta_c \\leq \\bar{\\beta} \\), then (OS.27) is negative, and, if \\( \\beta_c > \\bar{\\beta} \\), then (OS.27) is positive.\n\nConsequently, if \\( \\beta_c \\geq \\bar{\\beta} \\), the maximum originator profit in the region \\( e_o^p \\geq \\frac{(s_{co}^2)^2}{18\\beta_o(s_{oo}^2 - s_{co}^2)} \\) is greater than that in the region \\( e_o^p < \\frac{(s_{co}^2)^2}{18\\beta_o(s_{oo}^2 - s_{co}^2)} \\) and vice-versa otherwise. That is, the globally optimal effort level for the originator is \\( e_o^* = \\frac{s_{oo}^2}{4s_{so}} \\) if \\( \\beta_c \\geq \\bar{\\beta} \\), and \\( e_o^* = \\frac{5s_{oo}^2 + 4s_{co}^2}{9\\beta_o} \\) if \\( \\frac{2(s_{co}^2)^2\\beta_o}{(s_{oo}^2 - s_{co}^2)(5s_{oo}^2 + 4s_{co}^2)} \\leq \\beta_c \\). Moreover, the former is in the effort region where the contributor will be out of the market and the latter is in the region where the contributor will be active and the quality leader.\nCombining the above three cases, gives us the results stated in parts (i) and (ii). Now, substituting these effort levels into the quality and price expressions given in the Proof of Proposition 1 and contributor effort level expressions given in the Proof of Proposition 2, we obtain\n\n(i) If \\( \\beta_c < \\bar{r} \\), then\n\\[\ne_p^* = \\frac{5s_{pp}^P + 4s_{ppo}^P}{36\\beta_o},\n\\]\n\\[\ne_c^* = \\frac{s_{po}^P}{9\\beta_o},\n\\]\n\\[\nQ_o^* = \\frac{s_{ppo}^P + 4s_{po}^P}{36\\beta_o},\n\\]\n\\[\nQ_c^* = \\frac{s_{pp}^P + 4s_{po}^P}{36\\beta_o} + \\frac{(s_{pp}^P)^2}{9\\beta_o},\n\\]\n\n\\[\np_{P*} = \\frac{1}{216} \\left( (s_{ppo}^P + 2s_{ppo}^P)(5s_{ppo}^P + 4s_{po}^P) + \\frac{8(s_{pp}^P)^2}{\\beta_c} \\right),\n\\] \n\n(OS.29)\n\n\\[\np_{o*} = \\frac{1}{108} \\left( (s_{ppo}^P - s_{ppo}^P)(5s_{ppo}^P + 4s_{po}^P) - \\frac{4(s_{pp}^P)^2}{\\beta_c} \\right),\n\\] \n\n(OS.30)\n\nand\n\n\\[\np_{c*} = \\frac{1}{108} \\left( (s_{ppo}^P - s_{ppo}^P)(5s_{ppo}^P + 4s_{po}^P) + \\frac{4(s_{pp}^P)^2}{\\beta_c} \\right).\n\\] \n\n(OS.31)\n\n(ii) If \\( \\beta_c \\geq \\bar{r} \\), then\n\\[\ne_o^* = \\frac{s_{po}^P}{4\\beta_o},\ne_c^* = 0,\n\\]\n\\[\nQ_o^* = \\frac{(s_{pp}^P)^2}{4\\beta_o},\n\\]\n\\[\np_{o*} = \\frac{(s_{pp}^P)^2}{8\\beta_o},\n\\]\n\nand\n\\[\np_{o*} = 0.\n\\]\n\nFinally, substituting the above expressions into the consumer valuation cutoff expressions found in Lemma OS.1, yields the equilibrium consumer segments served by each firm as given in the statements of Propositions 3 and 4. ■\n\n**Lemma OS.2** For fixed \\( p_o^0 \\), \\( p_c^0 \\), \\( e_o^0 \\) and \\( e_c^0 \\),\n\n(i) If \\( Q_o^O = s_{oo}e_o^0 + s_{oo}e_c^0 > Q_c^O = s_{co}e_o^0 + s_{cc}e_c^0 \\), then the originator is the quality leader and the consumer market has the following characterization of regions:\n\n**Region I:** If \\( p_c^O \\geq Q_c^O \\) and \\( p_o^0 \\geq Q_o^O \\), then no consumer uses the software; \n\n**Region II:** If either \\( p_o^O \\geq Q_c^O \\) and \\( p_o^0 < Q_o^O \\), or \\( p_c^O < Q_c^O \\) and \\( p_o^0 \\leq p_c^O Q_o^0 / Q_c^0 \\), then\n\n(a) consumers with \\( \\theta \\in [0, p_o^0) \\) do not use the software, and\n\n(b) consumers with \\( \\theta \\in (p_o^0, 1] \\) contract with the originator; \n\n**Region III:** If \\( p_c^O < Q_c^O \\) and \\( p_o^0 Q_o^0 / Q_c^0 - p_c^O \\leq p_o^0 + Q_o^0 - Q_c^0 \\), then\n\n(a) consumers with \\( \\theta \\in [0, p_c^O / Q_c^0] \\) do not use the software,\n\n(b) consumers with \\( \\theta \\in (p_c^O / Q_c^0, p_o^0 - p_c^O / Q_c^0) \\) contract with the contributor, and\n\n(c) consumers with \\( \\theta \\in (p_o^0 - p_c^O / Q_c^0, 1] \\) contract with the originator; \n\n**Region IV:** If \\( p_c^O < Q_c^O \\) and \\( p_c^O + Q_c^O - Q_o^0 < p_o^0 \\), then\n\n(a) consumers with \\( \\theta \\in [0, p_o^0) \\) do not use any software, and\n\n(b) consumers with \\( \\theta \\in (p_o^0, 1] \\) contract with the contributor.\n\n(ii) If \\( Q_o^O < Q_c^O \\), then the contributor is the quality leader and the consumer market has the same characterization as in part (i), except only for switching \\( Q_o^O \\) and \\( Q_c^O \\), and \\( p_o^0 \\) and \\( p_c^0 \\) in all the expressions.\n\n(iii) If \\( Q_o^O = Q_c^O \\), then\n\nOS.13\nProof: For part (i), let $Q_o^C > Q_o^O$. By (2), a consumer with type $\\theta$,\n\n(a) prefers to contract with the originator rather than to not use the software if and only if $Q_o^C \\theta - p_o^O \\geq 0$, i.e., $\\theta \\geq \\theta_{oN}^O = p_o^O/Q_o^O$;\n\n(b) prefers to contract with the contributor rather than to not use if and only if $Q_c^O \\theta - p_c^O \\geq 0$, i.e., $\\theta \\geq \\theta_{cN}^O = p_c^O/Q_c^O$; and\n\n(c) prefers to contract with the originator rather than the contributor if and only if $Q_o^C \\theta - p_o^O \\geq Q_c^O \\theta - p_c^O$, i.e., $\\theta \\geq \\theta_{oc} = (p_o^O - p_c^O)/(Q_o^O - Q_c^O)$.\n\nNow suppose $\\theta_{oN}^O = p_o^O/Q_o^O \\leq \\theta_{oc} \\leq p_c^O/Q_c^O$, then by carrying out the algebra, it follows that $\\theta_{oc} = (p_o^O - p_c^O)/(Q_o^O - Q_c^O) \\leq \\theta_{oN}^O = p_o^O/Q_o^O \\leq \\theta_{cN}^O = p_c^O/Q_c^O$. In this case, all consumers who prefer to contract with the contributor rather than to not use, i.e., consumers with $\\theta \\geq \\theta_{cN}^O$, prefer to contract with the originator rather than the contributor since for those consumers, $\\theta \\geq \\theta_{oc} \\geq \\theta_{oc}$. Thus, in this region, there are only two possible consumer choices: a consumer either contracts with the originator or does not use.\n\nConsequently, if $\\theta_{oN}^O \\geq 1$, i.e., if $p_o^O \\geq Q_o^O$ then no consumer uses the software. Notice that in this case, if $p_o^O \\geq Q_o^O$, it also means that $p_c^O \\geq Q_c^O$, since $\\theta_{oN}^O = p_o^O/Q_o^O \\leq \\theta_{oc} = p_c^O/Q_c^O$. That is, in Region I, as defined in part (i), no consumer uses the software. On the other hand, if $\\theta_{oN}^O < 1$, i.e., if $p_o^O \\leq Q_o^O$, then consumers with types $\\theta \\in (\\theta_{oN}^O, 1]$ contract with the originator and the rest, i.e., those with $\\theta \\in [0, \\theta_{oN}^O]$ do not use the software. Again notice that $p_o^O/Q_o^O \\leq p_c^O/Q_c^O$ and $p_c^O \\leq Q_c^O$ implies either $p_c^O \\geq Q_c^O$ and $p_o^O < Q_o^O$, or $p_c^O < Q_c^O$ and $p_o^O \\leq p_c^O/Q_c^O$, i.e., Region II as defined above, therefore the statement for this region is also confirmed.\n\nNext suppose $\\theta_{oN}^O = p_o^O/Q_o^O \\geq \\theta_{cN}^O = p_c^O/Q_c^O$. Then we have $\\theta_{oc} = (p_o^O - p_c^O)/(Q_o^O - Q_c^O) \\geq \\theta_{oN}^O = p_o^O/Q_o^O \\geq \\theta_{cN}^O = p_c^O/Q_c^O$. Thus, in this case, if $\\theta \\leq \\theta_{oc} = (p_o^O - p_c^O)/(Q_o^O - Q_c^O)$, then a consumer with type $\\theta$ always prefers to contract with the contributor given that she chooses to use the software. This means that if $\\theta_{oc} < 1$, then consumers with types $\\theta \\in (\\theta_{oc}, 1]$ contract with the originator; consumers with types $\\theta \\in (\\theta_{oc}, \\theta_{oc}]$ contract with the contributor; and the rest with types $\\theta \\in [0, \\theta_{oc}]$ do not use the software. Notice that since $Q_o^O > Q_c^O$, $\\theta_{oc} < 1$ if and only if $p_o^O \\leq p_c^O + Q_o^O - Q_c^O$. Therefore, if $\\theta_{cN}^O = p_c^O/Q_c^O < 1$, that is, $p_c^O < Q_c^O$, and $p_c^O Q_o^O/Q_c^O < p_o^O \\leq p_c^O + Q_o^O - Q_c^O$, i.e., in Region III, the consumer market will be split as described in the statement of the lemma. On the other hand, if $p_o^O > p_c^O + Q_o^O - Q_c^O$, i.e., in Region IV, then no consumer with type $\\theta \\in [0, 1]$ will prefer to contract with the originator over the contributor, and hence consumers with types $\\theta \\in (\\theta_{cN}^O, 1]$ contract with the contributor and the rest with...\ntypes \\( \\theta \\in [0, \\theta_{cN}] \\) do not use the software as stated. This proves part (i). Part (ii) follows in the exact same manner except the originator and the contributor are switched.\n\nFor part (iii), when \\( Q_o^O = Q_c^O \\), there is no product differentiation and, as in a standard Bertrand competition case, all consumers prefer the lower priced service if there is a difference in prices. If the prices are the same, all consumers are indifferent and they choose between the two providers randomly. This completes the proof. \\( \\square \\)\n\n**Proof of Proposition 5**: Technically, we will prove that, given \\( e_o^P \\) and \\( e_c^P \\),\n\n(i) If \\( Q_o^O = s_{oo} e_o^O + s_{oc} e_c^O > Q_c^O = s_{co} e_o^O + s_{cc} e_c^O \\), then\n\n\\[\np_o^{O*} = \\frac{2(s_{oo} e_o^O + s_{oc} e_c^O)((s_{oo} - s_{oo})e_o^O + (s_{oc} - s_{oc})e_c^O)}{(4s_{oo} - s_{co})e_o^O + (4s_{oc} - s_{cc})e_c^O},\n\\]\n\n\\[\np_c^{O*} = \\frac{(s_{co} e_o^O + s_{cc} e_c^O)((s_{co} - s_{co})e_o^O + (s_{cc} - s_{cc})e_c^O)}{(4s_{oo} - s_{co})e_o^O + (4s_{oc} - s_{cc})e_c^O}.\n\\]\n\nHowever, if \\( Q_o^O < Q_c^O \\), then the prices are symmetric and reversed.\n\n(ii) If \\( Q_o^O = Q_c^O \\), then \\( p_o^{O*} = p_c^{O*} = 0 \\).\n\nWe illustrate the profits and pricing game for the case in which the originator is the quality leader, i.e., \\( Q_o^O = s_{oo} e_o^O + s_{oc} e_c^O > Q_c^O = s_{co} e_o^O + s_{cc} e_c^O \\). Using Lemma OS.2, in the pricing stage, given the investment levels \\( e_o^O \\) and \\( e_c^O \\), the originator’s profit function (excluding the effort cost) can be written as follows:\n\n(i) If \\( p_c^O < Q_c^O \\), then\n\n\\[\n\\tilde{\\Pi}_o^O(p_o^O | p_c^O, e_o^O, e_c^O) = \\begin{cases} \n p_o^O \\left(1 - \\frac{p_o^O}{s_{oo} e_o^O + s_{oc} e_c^O}\right) & \\text{if } p_o^O \\leq \\frac{s_{oo} e_o^O + s_{oc} e_c^O}{s_{oo} + s_{oc}}; \\\\\n p_o^O \\left(1 - \\frac{p_o^O - p_c^O}{s_{oo} - s_{oo} e_o^O + s_{oc} e_c^O}\right) & \\text{if } \\frac{s_{oo} e_o^O + s_{oc} e_c^O}{s_{oo} + s_{oc}} < p_o^O \\leq p_c^O + (s_{oo} - s_{oo} e_o^O + s_{oc} e_c^O); \\\\\n 0 & \\text{if } p_c^O + (s_{oo} - s_{oo} e_o^O + s_{oc} e_c^O) < p_o^O.\n\\end{cases}\n\\]\n\n(ii) If \\( p_c^O \\geq Q_c^O \\), then\n\n\\[\n\\tilde{\\Pi}_o^O(p_o^O | p_c^O, e_o^O, e_c^O) = \\begin{cases} \n p_o^O \\left(1 - \\frac{p_o^O}{s_{oo} e_o^O + s_{oc} e_c^O}\right) & \\text{if } p_o^O < s_{oo} e_o^O + s_{oc} e_c^O; \\\\\n 0 & \\text{if } p_o^O \\geq Q_o^O = s_{oo} e_o^O + s_{oc} e_c^O.\n\\end{cases}\n\\]\n\nSimilarly the contributor’s profit (excluding effort costs) is:\n\nOS.15\n(i) If $p_c^O < Q_o^O$,\n\\[\n\\bar{\\Pi}^O_c(p_c^O | p_o^O, e_o^O, e_c^O) = \\begin{cases} \n\\frac{p_c^O}{s_{oo} c_o^O + s_{oc} e_c^O} & \\text{if } p_c^O \\leq p_o^O - (s_{oo}^O - s_{co}^O)e_o^O - (s_{oc}^O - s_{cc}^O)e_c^O \\\\\n\\frac{p_c^O}{s_{oo} c_o^O + s_{oc} e_c^O} - \\frac{p_c^O}{s_{oo} c_o^O + s_{oc} e_c^O} & \\text{if } p_o^O - (s_{oo}^O - s_{co}^O)e_o^O - (s_{oc}^O - s_{cc}^O)e_c^O < p_c^O \\leq \\frac{p_o^O (s_{oo} c_o^O + s_{oc} e_c^O)}{s_{oo} c_o^O + s_{oc} e_c^O}; \\\\\n0 & \\text{if } \\frac{p_o^O (s_{oo} c_o^O + s_{oc} e_c^O)}{s_{oo} c_o^O + s_{oc} e_c^O} < p_c^O. \n\\end{cases}\n\\]\n\n(OS.36)\n\n(ii) If $p_c^O \\geq Q_o^O$,\n\\[\n\\bar{\\Pi}^O_c(p_c^O | p_o^O, e_o^O, e_c^O) = \\begin{cases} \n\\frac{p_c^O}{s_{oo} c_o^O + s_{oc} e_c^O} & \\text{if } p_c^O < s_{oo}^O e_o^O + s_{oc}^O e_c^O; \\\\\n0 & \\text{if } p_c^O \\geq s_{oo}^O e_o^O + s_{oc}^O e_c^O. \n\\end{cases}\n\\]\n\n(OS.37)\n\nNote that if the contributor is the quality leader, i.e., if $Q_c^O = (s_{oo}^O c_o^O + s_{oc}^O e_c^O) > Q_o^O = (s_{oo}^O e_o^O + s_{oc}^O e_c^O)$, then we will have the exact symmetric expressions for the profits with the originator's and the contributor's roles reversed.\n\nTo see part (i), we first derive the originator's best response price function, $B_{p^O_0}(p_c^O)$. If $p_c^O < Q_o^O$, then as can be seen from (OS.34), the originator's profit function is piecewise quadratic in $p_o^O$. The first quadratic part has its unrestricted maximizer at $p_o^{O1} = (s_{oo}^O e_o^O + s_{oc}^O e_c^O)/2$. This local maximizer will be located in the region where the first quadratic curve applies if and only if\n\\[\n\\frac{s_{oo}^O e_o^O + s_{oc}^O e_c^O}{2} \\leq \\frac{p_o^O (s_{oo}^O e_o^O + s_{oc}^O e_c^O)}{s_{oo}^O e_o^O + s_{oc}^O e_c^O},\n\\]\n\nwhich is equivalent to $(s_{oo}^O e_o^O + s_{oc}^O e_c^O)/2 < p_c^O$. Similarly, the second quadratic part has its unrestricted maximizer at $p_o^O = ((s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O + p_c^O)/2$, and this maximizer falls into the region where this quadratic is applicable if and only if\n\\[\n\\frac{p_c^O (s_{oo}^O c_o^O + s_{oc}^O c_c^O)}{s_{oo}^O e_o^O + s_{oc}^O e_c^O} < \\frac{(s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O + p_c^O}{2} \\leq p_c^O + (s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O.\n\\]\n\n(OS.39)\n\nApplying simple algebraic manipulations on (OS.39), we can see that the second inequality is always satisfied and the first inequality is equivalent to\n\\[\np_c^O \\leq \\frac{(s_{oo}^O e_o^O + s_{oc}^O e_c^O)((s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O)}{(2s_{oo}^O - s_{co}^O)e_o^O + (2s_{oc}^O - s_{cc}^O)e_c^O).}\n\\]\n\n(OS.40)\n\nNext, again by simple algebraic manipulations, one can see that\n\\[\n\\frac{(s_{oo}^O e_o^O + s_{oc}^O e_c^O)((s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O)}{(2s_{oo}^O - s_{co}^O)e_o^O + (2s_{oc}^O - s_{cc}^O)e_c^O} < \\frac{s_{oo}^O e_o^O + s_{oc}^O e_c^O}{2}.\n\\]\n\n(OS.41)\nTherefore, if\n\\[ p_0^O \\leq \\frac{(s_{oo}^O e_o^O + s_{co}^O e_c^O)((s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O)}{(2s_{oo}^O - s_{co}^O)e_o^O + (2s_{oc}^O - s_{cc}^O)e_c^O}, \\]\nthen \\( \\bar{H}_O(p_0^O | p_c^O, e_o^O, e_c^O) \\) in (OS.34) is increasing in \\( p_o^O \\) in the region of\n\\[ p_o^O \\leq \\frac{(p_c^O(s_{oo}^O e_o^O + s_{cc}^O e_c^O))}{(s_{co}^O e_o^O + s_{cc}^O e_c^O)}, \\]\nachieves the local maximum and is in the interior of the region\n\\[ \\frac{p_c^O(s_{oo}^O e_o^O + s_{cc}^O e_c^O)}{(s_{co}^O e_o^O + s_{cc}^O e_c^O)} < p_o^O \\leq p_c^O + (s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O. \\]\nHence, in this case, the local maximizer of the second quadratic, which is \\( ((s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O + p_c^O)/2 \\) is the optimum. Furthermore, if\n\\[ \\frac{(s_{oo}^O e_o^O + s_{cc}^O e_c^O)((s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O)}{(2s_{oo}^O - s_{co}^O)e_o^O + (2s_{oc}^O - s_{cc}^O)e_c^O} < p_c^O \\leq \\frac{(s_{oo}^O e_o^O + s_{cc}^O e_c^O)}{2}, \\]\nthen \\( \\bar{H}_O(p_0^O | p_c^O, e_o^O, e_c^O) \\) in (OS.34) is increasing in \\( p_o^O \\) in the region of\n\\[ p_o^O \\leq \\frac{p_c^O(s_{oo}^O e_o^O + s_{cc}^O e_c^O)}{(s_{co}^O e_o^O + s_{cc}^O e_c^O)}, \\]\nand is decreasing in \\( p_o^O \\) in the region of\n\\[ \\frac{p_c^O(s_{oo}^O e_o^O + s_{cc}^O e_c^O)}{(s_{co}^O e_o^O + s_{cc}^O e_c^O)} < p_o^O \\leq p_c^O + (s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O. \\]\nConsequently, the global optimum is the boundary \\( p_c^O \\) value between the two quadratic parts, which, by (OS.34), is \\( p_c^O(s_{oo}^O e_o^O + s_{oc}^O e_c^O)/(s_{oo}^O e_o^O + s_{cc}^O e_c^O). \\) Lastly, if \\( (s_{oo}^O e_o^O + s_{cc}^O e_c^O)/2 < p_c^O \\), then \\( \\bar{H}_O(p_0^O | p_c^O, e_o^O, e_c^O) \\) in (OS.34) achieves the local maximum in the region of\n\\[ p_o^O \\leq \\frac{p_c^O(s_{oo}^O e_o^O + s_{cc}^O e_c^O)}{(s_{co}^O e_o^O + s_{cc}^O e_c^O)}, \\]\nwhile it is decreasing in the region of\n\\[ \\frac{p_c^O(s_{oo}^O e_o^O + s_{cc}^O e_c^O)}{(s_{co}^O e_o^O + s_{cc}^O e_c^O)} < p_o^O \\leq p_c^O + (s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O. \\]\nTherefore the optimum \\( p_o^O \\) becomes the local maximizer in the first region, which is \\( (s_{oo}^O e_o^O + s_{cc}^O e_c^O)/2. \\)\n\nIn short, the best response price function for the originator for \\( p_c^O < Q_c^O \\) can be summarized as\n\\[\nB_{p_c^O}(p_o^O) = \\begin{cases} \n\\frac{(s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O + p_c^O}{2} & \\text{if } p_c^O < \\frac{(s_{oo}^O e_o^O + s_{cc}^O e_c^O)((s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O)}{(2s_{oo}^O - s_{co}^O)e_o^O + (2s_{oc}^O - s_{cc}^O)e_c^O}; \\\\\n\\frac{p_c^O(s_{oo}^O e_o^O + s_{cc}^O e_c^O)}{(s_{co}^O e_o^O + s_{cc}^O e_c^O)} & \\text{if } \\frac{(s_{oo}^O e_o^O + s_{cc}^O e_c^O)((s_{oo}^O - s_{co}^O)e_o^O + (s_{oc}^O - s_{cc}^O)e_c^O)}{(2s_{oo}^O - s_{co}^O)e_o^O + (2s_{oc}^O - s_{cc}^O)e_c^O} < p_c^O \\leq \\frac{s_{oo}^O e_o^O + s_{cc}^O e_c^O}{2}; \\\\\n\\frac{s_{oo}^O e_o^O + s_{cc}^O e_c^O}{2} & \\text{if } \\frac{s_{oo}^O e_o^O + s_{cc}^O e_c^O}{2} < p_c^O.\n\\end{cases}\n\\]\n\nOS.17\nOn the other hand, if $p_c^O \\geq Q_c^O$, then maximizing (OS.35) with respect to $p_o^O$, we obtain\n\n$$B_{p_c^O}(p_o^O) = \\frac{s_{oo}^O e_o^O + s_{oc}^O e_c^O}{2},$$\n\n(OS.51)\n\nwhich is the same for the final case given in (OS.50). Combining both cases, we can then conclude that the originator’s best response price given the contributor’s price, is the same as stated in (OS.50).\n\nSimilarly, the contributor’s best response price function $B_{p_c^O}(p_o^O)$, can be written as:\n\n$$B_{p_c^O}(p_o^O) =\n\\begin{cases}\n\\frac{(s_{oo}^O e_o^O + s_{oc}^O e_c^O) p_o^O}{2(s_{oo}^O e_o^O + s_{oc}^O e_c^O)} & \\text{if } p_o^O \\leq \\frac{2(s_{oo}^O e_o^O + s_{oc}^O e_c^O)((s_{oc}^O - s_{oo}^O)c_c^O + (s_{oo}^O - s_{oc}^O)c_o^O)}{(2s_{oo}^O - s_{oc}^O)c_c^O + (2s_{oc}^O - s_{oo}^O)c_o^O};\n\n\\frac{p_o^O}{2} & \\text{if } \\frac{(2s_{oo}^O - s_{oc}^O)c_c^O + (2s_{oc}^O - s_{oo}^O)c_o^O}{2} < p_o^O \\leq \\frac{(2s_{oo}^O - s_{oc}^O)c_c^O + (2s_{oc}^O - s_{oo}^O)c_o^O}{2};\n\n\\frac{(2s_{oo}^O - s_{oc}^O)c_c^O + (2s_{oc}^O - s_{oo}^O)c_o^O}{2} & \\text{if } \\frac{(2s_{oo}^O - s_{oc}^O)c_c^O + (2s_{oc}^O - s_{oo}^O)c_o^O}{2} < p_o^O.\n\\end{cases}$$\n\n(OS.52)\n\nThe Nash Equilibrium prices, can then be found by simultaneously solving the equations\n\n$$B_{p_c^O}(p_o^{O*}) = p_c^{O*} \\text{ and } B_{p_o^O}(p_c^{O*}) = p_o^{O*}$$\n\n(OS.53)\n\nwhich, carrying the algebra, leads to (OS.32) and (OS.33). The analysis for the case where the contributor is the quality leader uses the exact symmetric argument. This completes the proof of part (i). For part (ii), notice that when the firms have no difference in quality of service, the competition boils down to standard Bertrand setting, which means both firms in equilibrium set their prices equal to their cost, which is zero.\n\n\\[\\square\\]\n\n**Proof of Propositions 6 and 7:** Before analyzing the originator’s optimal effort investment level, we first study the contributor’s optimal effort level $e_c^O$ given the originator’s effort level $e_o^O$. Given $e_o^O$, combining equations (OS.36) and (OS.37) with Lemma OS.2 and Proposition 5, the contributor’s profit function and effort investment maximization problem can be written as\n\n$$\\max_{e_c^O \\geq 0} \\Pi_c^O(e_c^O | e_o^O) = \\tilde{\\Pi}_c^O(p_c^O | (p_o^O, e_o^O), (e_o^O, e_c^O)) - \\frac{1}{2} \\beta_c(e_c^O)^2,$$\n\n(OS.54)\n\nwhere $\\tilde{\\Pi}_c^O(e_c^O | e_o^O) = 0$ if $Q_o = Q_c$, and otherwise\n\n$$\\tilde{\\Pi}_c^O(e_c^O | e_o^O) =\n\\begin{cases}\n\\frac{(s_{oo}^O e_o^O + s_{oc}^O e_c^O)(e_{oo}^O s_{oo}^O + e_{oc}^O s_{oc}^O)(e_{oo}^O (s_{oc}^O - s_{oo}^O) + e_{oc}^O (s_{oo}^O - s_{oc}^O))}{(e_{oo}^O (4s_{oc}^O - s_{oo}^O) + e_{oc}^O (4s_{oo}^O - s_{oc}^O))^2} & \\text{(Curve Ic) if } s_{cc}^O \\leq s_{oc}^O \\text{ or } s_{cc}^O > s_{oc}^O \\text{ and } e_c^O = \\frac{s_{oo}^O - s_{oc}^O}{s_{oc}^O - s_{oo}^O} e_o^O;\n\n\\frac{4(e_{oo}^O s_{oo}^O + e_{oc}^O s_{oc}^O)^2}{} & \\text{(Curve IIc) if } s_{cc}^O > s_{oc}^O \\text{ and } e_c^O > \\frac{s_{oo}^O - s_{oc}^O}{s_{oc}^O - s_{oo}^O} e_o^O.\n\\end{cases}$$\n\n(OS.55)\nNote that in the region valid for Curve Ic as defined in (OS.55), the originator is the quality leader, while in the region valid for Curve IIc, the contributor is the quality leader. Further, both Curves Ic and IIc are strictly concave. We first present the contributor’s optimal effort level characterization in the following Lemma:\n\n**Lemma OS.3** Define \\( s_{oo} \\) as the unique solution on \\( s_{oc}^O \\geq s_{cc}^O \\) of the third degree polynomial equation\n\n\\[\n4s_{cc}^O(s_{oo}^O)^3 - 7s_{oc}^O s_{cc}^O(s_{oo}^O)^2 + 2s_{oc}^O s_{cc}^O(s_{oo}^O)^2 + s_{oc}^O(s_{cc}^O)^3 = 0, \\quad (OS.56)\n\\]\n\nand let Curve Ic and Curve IIc be as defined in (OS.55). Given \\( e_o^O \\geq 0 \\), the solution \\( e_c^O(e_o^O) \\geq 0 \\) to the contributor’s problem (OS.54) is characterized as follows:\n\n(i) If \\( s_{cc}^O \\leq s_{oc}^O \\), or \\( s_{cc}^O > s_{oc}^O \\) and \\( s_{oo}^O \\geq s_{co}^O \\) and \\( e_o^O > \\frac{4(s_{oc}^O - s_{cc}^O)^2}{9s_{cc}^O(s_{oo}^O - s_{co}^O)} \\), then the contributor’s profit as a function of \\( e_c^O \\) is unimodal and \\( e_c^O(e_o^O) \\geq 0 \\) is the interior maximizer of Curve Ic, and the originator is the quality leader.²\n\n(ii) If \\( s_{cc}^O > s_{oc}^O \\) and \\( s_{oo}^O \\geq s_{oo}^O \\) and \\( 0 < e_o^O \\leq \\frac{4(s_{cc}^O - s_{oc}^O)^2}{9s_{cc}^O(s_{oo}^O - s_{co}^O)} \\), then the contributor’s profit is bimodal and piecewise concave with the two local maximizers. The contributor chooses his optimal effort level between the interior optimizers of Curve Ic and Curve IIc, whichever yields a higher profit.\n\n(iii) If \\( s_{cc}^O > s_{oc}^O \\) and \\( s_{oo}^O < s_{oo}^O \\) and \\( e_o^O > \\frac{4(s_{cc}^O - s_{oc}^O)^2}{9s_{cc}^O(s_{oo}^O - s_{co}^O)} \\), then the contributor’s profit as a function of \\( e_c^O \\) is decreasing. Therefore \\( e_c^O = 0 \\), and the originator is the quality leader.\n\n(iv) If \\( s_{cc}^O > s_{oc}^O \\) and \\( s_{oo}^O < s_{oo}^O \\) and \\( e_o^O \\leq \\frac{4(s_{cc}^O - s_{oc}^O)^2}{9s_{cc}^O(s_{oo}^O - s_{co}^O)} \\), then the contributor’s profit is decreasing on \\( e_c^O \\leq \\frac{s_{cc}^O - s_{oc}^O}{s_{cc}^O - s_{oo}^O}e_o^O \\) and unimodal afterwards with an interior optimizer. The contributor chooses his optimal effort level between \\( e_c^O = 0 \\) and the interior optimizer of Curve IIc, whichever yields a higher profit.\n\n**Proof:** First, suppose that the originator is the quality leader, i.e., \\( Q_o^O = s_{oo}^O e_o^O + s_{oc}^O e_c^O > Q_c^O = s_{cc}^O e_o^O + s_{cc}^O e_c^O \\). In this case, the contributor’s profit (except the investment cost) corresponds to Curve Ic presented in (OS.55), and including the investment cost, we obtain the contributor’s profit function as follows:\n\n\\[\n\\Pi_c(e_c|e_o) = \\frac{(e_o s_{co}^O + e_c s_{cc}^O)(e_o s_{oo}^O + e_c s_{cc}^O)}{(e_o (4s_{cc}^O - s_{oc}^O) + e_c (4s_{cc}^O - s_{oc}^O))^2} - \\frac{1}{2} s_{cc}^O e_c^2. \\quad (OS.57)\n\\]\n\nBy taking the derivative of (OS.57) with respect to \\( e_c \\), we obtain the following first order condition:\n\n\\[\nA_0 + A_1 e_c + A_2 e_c^2 + A_3 e_c^3 + A_4 e_c^4 = 0, \\quad (OS.58)\n\\]\n\n²The equations that the interior optimizers of Curves Ic and IIc satisfy are fourth order polynomials. We give the full precise expressions of these polynomials in the proof of this proposition, which is provided in the proof.\nwhere\n\n\\[\nA_0 = -e_o^3 (s_{cc}^O (s_{co}^O)^2 (7 s_{cc}^O - 4 s_{co}^O) - (s_{co}^O)^2 s_{cc}^O (s_{co}^O + 2 s_{co}^O)),\n\\]\n\\[\nA_1 = e_o^2 \\left( 2 (s_{co}^O)^2 (s_{cc}^O)^2 - 7 (s_{co}^O)^2 (s_{cc}^O)^2 + 6 s_{co}^O s_{cc}^O (3 (s_{co}^O)^2 - 10 s_{co}^O s_{cc}^O + 12 (s_{cc}^O)^2) + e_o (s_{co}^O - 4 s_{cc}^O)^3 \\beta_c \\right),\n\\]\n\\[\nA_2 = 3 e_o (s_{co}^O - 4 s_{cc}^O) ((s_{cc}^O)^2 s_{cc}^O - 4 e_o s_{co}^O (s_{cc}^O - 4 s_{co}^O) \\beta_c + s_{cc}^O (- (s_{co}^O)^2 + e_o (s_{cc}^O - 4 s_{co}^O) \\beta_c)),\n\\]\n\\[\nA_3 = (s_{cc}^O - 4 s_{co}^O) ((s_{co}^O)^2 s_{cc}^O - 12 e_o s_{co}^O (s_{cc}^O - 4 s_{co}^O) \\beta_c - s_{cc}^O ((s_{co}^O)^2 - 3 e_o (s_{co}^O - 4 s_{co}^O) \\beta_c)),\n\\]\n\\[\nA_4 = (s_{cc}^O - 4 s_{co}^O)^3 \\beta_c.\n\\]\n\nFrom (OS.57), the second order condition is \\( e_c^2 \\):\n\n\\[\n\\frac{d^2 \\Pi_c^O(e_c|e_o)}{d e_c^2} = \\frac{-2 e_o^2 (s_{oo}^O s_{cc}^O - s_{co}^O s_{co}^O)^2}{(e_o (4 s_{oo}^O - s_{co}^O) + e_c (4 s_{oc}^O - s_{cc}^O))^4} - \\beta_c < 0,\n\\]\n\ni.e., Curve Ic is strictly concave in \\( e_c \\).\n\nFurther, note that again from (OS.57), the first derivative of Curve Ic at \\( e_c = 0 \\) is\n\n\\[\n\\left. \\frac{d \\Pi_c^O(e_c|e_o)}{d e_c} \\right|_{e_c=0} = \\frac{h(s_{oo}^O)}{(4 s_{oo}^O - s_{co}^O)^3},\n\\]\n\nwhere\n\n\\[\nh(s_{oo}^O) = (s_{oo}^O)^2 s_{cc}^O (4 s_{oo}^O - 7 s_{co}^O) + (s_{oo}^O)^2 s_{cc}^O (2 s_{oo}^O + s_{co}^O).\n\\]\n\nSecond, consider the case in which the contributor is the quality leader, i.e., \\( Q^O = s_{oo}^O e_o + s_{oc}^O e_c < Q^c = s_{cc}^O e_o + s_{cc}^O e_c \\). In this case, the contributor’s profit (except the investment cost) corresponds to Curve Ic presented in (OS.55), and including the investment cost, we obtain the contributor’s profit function as follows:\n\n\\[\n\\Pi_c^O(e_c|e_o) = \\frac{4 (e_o s_{co}^O + e_c s_{cc}^O)^2 (e_o (s_{co}^O - s_{oo}^O) + e_c (s_{cc}^O - s_{oo}^O))}{(e_o (4 s_{cc}^O - s_{co}^O) + e_c (4 s_{oc}^O - s_{cc}^O))^2} - \\frac{1}{2} \\beta_c e_c^2.\n\\]\n\nTaking the derivative of (OS.63) with respect to \\( e_c \\) and simplifying, we obtain the following first order condition:\n\n\\[\nB_0 + B_1 e_c + B_2 e_c^2 + B_3 e_c^3 + B_4 e_c^4 = 0,\n\\]\n\nwhere\n\n\\[\nB_0 = 4 e_o^3 s_{co}^O (s_{cc}^O (2 s_{cc}^O)^2 - 3 s_{cc}^O s_{co}^O + 4 (s_{cc}^O)^2) - s_{cc}^O s_{cc}^O (s_{cc}^O + 2 s_{co}^O)),\n\\]\n\\[\nB_1 = e_o^2 (8 (s_{cc}^O)^2 (s_{cc}^O)^2 - 3 s_{cc}^O s_{co}^O + 6 (s_{cc}^O)^2) - 4 e_o s_{co}^O s_{cc}^O (s_{co}^O - s_{cc}^O + 4 s_{cc}^O (9 s_{co}^O - 2 s_{co}^O)) + (s_{cc}^O - 4 s_{cc}^O)^3 \\beta_c e_o),\n\\]\n\\[\nB_2 = 3 e_o (s_{cc}^O - 4 s_{cc}^O) (4 s_{cc}^O - s_{cc}^O) (4 s_{cc}^O - s_{co}^O) \\beta_c e_o - 4 (s_{cc}^O)^2 (s_{cc}^O - s_{cc}^O) ,\n\\]\n\\[\nB_3 = (4 s_{cc}^O - s_{cc}^O) (4 (s_{cc}^O)^2 (s_{cc}^O - s_{cc}^O) + 3 (4 s_{cc}^O - s_{cc}^O) (s_{cc}^O - 4 s_{cc}^O) \\beta_c e_o),\n\\]\n\\[\nB_4 = - (4 s_{cc}^O - s_{cc}^O)^3 \\beta_c.\n\\]\nTaking the second order condition using (OS.64)\n\n\\[\n\\frac{d^2 \\Pi_c^O(e_c|e_o)}{d e_c^2} = -8\\epsilon_o^2 \\left( s_{cc}^O s_{oo}^O - s_{co}^O s_{oc}^O \\right)^2 \\left( e_o \\left( 5s_{cc}^O + s_{oo}^O \\right) + e_c \\left( 5s_{cc}^O + s_{oc}^O \\right) \\right) - \\beta_c < 0, \\tag{OS.66}\n\\]\n\nwhich shows that Curve IIc is also strictly concave in \\( e_c \\).\n\nNow, first consider the case in which \\( s_{cc}^O \\leq s_{oc}^O \\). Since \\( s_{oo}^O > s_{co}^O \\), in this case, we have \\( Q_c^O = s_{oo}^O e_o + s_{oc}^O e_c \\geq Q_c^O = s_{oo}^O e_o + s_{oc}^O e_c \\), i.e., the originator is the quality leader for all \\( e_c \\geq 0 \\) for any given \\( e_o \\geq 0 \\) and the contributor’s profit function in this regime is unimodal and that there exists the unique non-\n\nTo sum it up, consequently,\n\n\\[\n\\frac{d^2 \\Pi_c}{d e_c^2} = \\left( 4s_{cc}^O - s_{oo}^O \\right)^2 + e_c \\left( 4s_{cc}^O - s_{oc}^O \\right)^4 \\]\n\nwhich shows that Curve IIc is also strictly concave in \\( e_c \\).\n\nNow, first consider the case in which \\( s_{oo}^O > s_{co}^O \\). Since the second order condition is strictly negative in this region as shown in (OS.60), it follows that the originator is the quality leader for all \\( e_c \\geq 0 \\) for any given \\( e_o \\geq 0 \\) and the contributor’s profit function in this regime is unimodal and that there exists the unique non-\n\nMoreover, since \\( s_{oc}^O \\geq s_{cc}^O \\)\n\n\\[\nh'(s_{oo}^O) = 2(s_{cc}^O)^2(s_{oc}^O - s_{cc}^O) \\geq 0.\n\\]\n\nConsequently, \\( h(s_{oo}^O) \\) is strictly increasing in \\( s_{oo}^O \\) for \\( s_{oo}^O > s_{co}^O \\). Finally, we also have\n\n\\[\nh(s_{co}^O) = 3(s_{cc}^O)^3(s_{oc}^O - s_{cc}^O) \\geq 0.\n\\]\n\nTo sum it up, \\( h \\) is positive and increasing at \\( s_{co}^O \\), and the first derivative of \\( h \\) is strictly increasing for all \\( s_{oo}^O \\leq s_{co}^O \\), which means \\( h \\) will be increasing for all \\( s_{oo}^O \\geq s_{co}^O \\). Therefore, \\( h(s_{oo}^O) > 0 \\) for all \\( s_{oo}^O > s_{co}^O \\). Hence, we have shown that by (OS.61), \\( h(s_{oo}^O) > 0 \\) for all \\( s_{oo}^O > s_{co}^O \\). Moreover, also note that, by (OS.57), for Curve Ic\n\n\\[\n\\lim_{e_c \\to -\\infty} \\Pi_c^O(e_c|e_o) = \\lim_{e_c \\to -\\infty} \\left\\{ \\frac{s_{cc}^O s_{oo}^O(s_{oc}^O - s_{cc}^O)}{4s_{cc}^O - s_{oc}^O} - e_c - \\frac{1}{2} \\beta_c e_c^2 \\right\\} = -\\infty.\n\\]\n\nSince the second order condition is strictly negative in this region as shown in (OS.66), it follows that the contributor’s profit function in this regime is unimodal and that there exists the unique non-\n\nFinally, consider the case in which \\( s_{oc}^O > s_{cc}^O \\). In order to show the remaining statements in parts (i)-(iv), we first have to study some characteristics of Curves Ic and IIc, which together form the entire profit curve for the contributor.\n\nWe start by showing that the derivative of Curve Ic with respect to \\( e_c \\) evaluated at \\( e_c = \\frac{d s_{oo}^O \\cdot s_{co}^O}{s_{cc}^O - s_{oc}^O} e_o \\) is negative. Taking the first derivative of (OS.57) with respect to \\( e_c \\), and since \\( s_{oo}^O > s_{co}^O \\), we have\n\n\\[\n\\frac{d \\Pi_c^O(e_c|e_o)}{d e_c} \\bigg|_{e_c = \\frac{d s_{oo}^O \\cdot s_{co}^O}{s_{cc}^O - s_{oc}^O} e_o} = -\\frac{(s_{cc}^O - s_{oc}^O)^2 + 9(s_{oo}^O - s_{co}^O)e_o}{9(s_{cc}^O - s_{oc}^O)^2} < 0.\n\\]\nFurther, evaluating the contributor’s profit for Curve IIc in (OS.55) as $e_c \\to \\infty$, we have\n\n$$\\lim_{e_c \\to \\infty} \\Pi_c^O(e_c|e_0) = \\lim_{e_c \\to \\infty} \\left\\{ \\frac{4(s_{cc}^O)^2(s_{cc}^O - s_{oc}^O)}{(4s_{cc}^O - s_{oc}^O)^2} e_c - \\frac{1}{2} \\beta c^2 \\right\\} = -\\infty.$$ \\hspace{1cm} (OS.73)\n\nNext, we show that the derivative of the contributor’s profit corresponding to Curve Ic in (OS.55) with respect to $e_c$ evaluated at $e_c = 0$ presented in (OS.61) is positive if and only if $s_{co}^O > s_{oo}^O$. Note that as we have shown in (OS.68), $h(s_{co}^O)$ is strictly convex in $s_{co}^O$. Moreover, in this case,\n\n$$h(s_{co}^O) = 3(s_{co}^O)^3(s_{oc}^O - s_{co}^O) \\leq 0,$$ \\hspace{1cm} (OS.74)\n\nand $\\lim_{s_{co}^O \\to \\infty} h(s_{co}^O) = \\infty$. Consequently, there exists the unique threshold $\\bar{s}_{oo} > s_{co}^O$, which solves $h(s_{co}^O) = 0$ in (OS.56), and for this threshold, $h(s_{co}^O) < 0$ if $s_{co}^O < s_{co}^O < \\bar{s}_{oo}$, and $h(s_{co}^O) > 0$ if $s_{co}^O > \\bar{s}_{oo}$. Therefore, for Curve Ic,\n\n$$\\frac{d\\Pi_c^O(e_c|e_0)}{de_c} \\bigg|_{e_c=0} > 0 \\text{ if and only if } s_{co}^O > \\bar{s}_{oo}.$$ \\hspace{1cm} (OS.75)\n\nFinally, let us also examine the derivative of Curve IIc at the junction of the two curves Ic and Iic, i.e., at $e_c = \\frac{s_{co}^O - s_{oc}^O}{s_{cc}^O - s_{oc}^O} e_0$. From (OS.63), the derivative of Curve IIc with respect to $e_c$ evaluated at this junction point is\n\n$$\\frac{d\\Pi_c^O(e_c|e_0)}{de_c} \\bigg|_{e_c=0} = \\frac{4(s_{cc}^O - s_{oc}^O)^2 - 9(s_{oo}^O - s_{co}^O)\\beta c e_0}{9(s_{cc}^O - s_{oc}^O)^2}.$$ \\hspace{1cm} (OS.76)\n\nSince $s_{oo}^O > s_{co}^O$, it follows that this derivative is positive if and only if $e_0 < \\frac{4(s_{cc}^O - s_{oc}^O)^2}{9(s_{oo}^O - s_{co}^O)\\beta c}$. Consequently, there exists the unique threshold $\\bar{s}_{oo}$, as we have shown above, Curve Ic is increasing in $s_{co}^O$ and $\\bar{s}_{oo} = \\frac{4(s_{cc}^O - s_{oc}^O)^2}{9(s_{oo}^O - s_{co}^O)\\beta c}$. Therefore, we can conclude that if $s_{cc}^O > s_{co}^O$, $s_{oo}^O \\geq \\bar{s}_{oo}$ and $e_0 > \\frac{4(s_{cc}^O - s_{oc}^O)^2}{9(s_{oo}^O - s_{co}^O)\\beta c}$, then the contributor’s profit function is unimodal and is maximized at the interior maximizer of Curve Ic and the originator is the quality leader. This completes the proof of part (i).\n\nTo see part (ii), first, for $s_{oo}^O \\geq \\bar{s}_{oo}$, as we have shown above, Curve Ic is increasing in $e_c$ at $e_c = 0$ and identical to our argument above, it is unimodal and has a unique interior maximizer on $0 \\leq e_c < \\frac{(s_{cc}^O - s_{oc}^O)e_0}{s_{cc}^O - s_{oc}^O}$. In this case however, for $e_0 \\leq \\frac{4(s_{cc}^O - s_{oc}^O)^2}{9(s_{oo}^O - s_{co}^O)\\beta c}$, as we have shown above, Curve Ic is increasing at $e_c = \\frac{(s_{cc}^O - s_{oc}^O)e_0}{s_{cc}^O - s_{oc}^O}$, and since Curve Ic is strictly concave, it is also unimodal and has a unique interior maximizer on the range $e_c > \\frac{(s_{cc}^O - s_{oc}^O)e_0}{s_{cc}^O - s_{oc}^O}$. Therefore, we can conclude that if $s_{cc}^O > s_{co}^O$, $s_{oo}^O \\geq \\bar{s}_{oo}$ and $e_0 > \\frac{4(s_{cc}^O - s_{oc}^O)^2}{9(s_{oo}^O - s_{co}^O)\\beta c}$, then the contributor’s overall profit function is bimodal and piecewise concave with two local maximizers. The global maximizer is the one that yields the higher profit.\n\nFor part (iii), given $s_{co}^O < \\bar{s}_{oo}$, Curve Ic is decreasing in $e_c$ at $e_c = 0$. Since it is strictly concave, it is monotonically decreasing on $0 \\leq e_c < \\frac{(s_{cc}^O - s_{oc}^O)e_0}{s_{cc}^O - s_{oc}^O}$. Further, since $e_0 > \\frac{4(s_{cc}^O - s_{oc}^O)^2}{9(s_{oo}^O - s_{co}^O)\\beta c}$, then similar to part (i), Curve Iic is monotonically decreasing on the entire range $e_c > \\frac{(s_{cc}^O - s_{oc}^O)e_0}{s_{cc}^O - s_{oc}^O}$. Therefore, the contributor’s\nprofit function is monotonically decreasing on the entire range \\( e_c \\geq 0 \\). Hence it is maximized at \\( e_c = 0 \\) and the originator is the quality leader.\n\nFinally, for part (iv), given \\( s_{oo}^O < \\bar{s}_{oo} \\), as we have shown above, Curve Ic, and hence the contributor’s profit function, is monotonically decreasing on \\( 0 \\leq e_c < (\\frac{s_{oo}^O - s_{oo}^O}{s_{oo}^c - s_{oo}^c})e_o \\). So, the maximizer of the profit function on \\( 0 \\leq e_c < (\\frac{s_{oo}^O - s_{oo}^O}{s_{oo}^c - s_{oo}^c})e_o \\) is \\( e_c = 0 \\). On the other hand, for \\( e_o \\leq 4(\\frac{s_{oo}^O - s_{oo}^O}{s_{oo}^c - s_{oo}^c})^2 \\), as we have shown above for part (ii), Curve Ic is unimodal and has a unique interior maximum. Therefore, the global maximizer of the contributor’s profit function can be found by comparing the profit levels at \\( e_c = 0 \\) and the interior maximizer of Curve Ic on \\( e_c > (\\frac{s_{oo}^O - s_{oo}^O}{s_{oo}^c - s_{oo}^c})e_o \\) as stated in part (iv). This completes the proof.\n\nGiven the contributor’s effort level \\( e_c^O(e_o) \\geq 0 \\) as the best response to \\( e_o \\) as presented in Lemma OS.3, the originator’s profit function can be written as\n\n\\[\n\\max_{e_o^*} \\quad \\Pi^O_o(e_o^*) = \\Pi^O_o(p_o^O(e_o^*), c_{oc}^O(e_o^*)) \\left| \\frac{p_o^O(e_o^*), c_{oc}^O(e_o^*)}{e_o^*, c_{oc}^O(e_o^*)} \\right| - \\frac{1}{2} \\beta_o(e_o^*)^2 \\tag{OS.77}\n\\]\n\nwhere \\( \\Pi^O_o(e_o^*, c_{oc}^O(e_o^*)) = 0 \\) if \\( Q^O_o = Q^O_c \\), and otherwise\n\n\\[\n\\Pi^O_o(e_o^*, c_{oc}^O(e_o^*)) = \\begin{cases} \n\\frac{(e_o^* + e_o^* - s_{oo}^O)(e_o^* + e_o^* - s_{oo}^O)(e_o^* + e_o^* - s_{oo}^O)}{4(e_o^* + e_o^* - s_{oo}^O)(e_o^* + e_o^* - s_{oo}^O)(e_o^* + e_o^* - s_{oo}^O)} & \\text{(Curve Io)} \\quad \\text{if } e_o^* < (\\frac{s_{oo}^O - s_{oo}^O}{s_{oo}^c - s_{oo}^c})e_o^*; \\\\\n\\frac{(e_o^* + e_o^* - s_{oo}^O)(e_o^* + e_o^* - s_{oo}^O)(e_o^* + e_o^* - s_{oo}^O)}{4(e_o^* + e_o^* - s_{oo}^O)(e_o^* + e_o^* - s_{oo}^O)(e_o^* + e_o^* - s_{oo}^O)} & \\text{(Curve IIo)} \\quad \\text{if } e_o^* > (\\frac{s_{oo}^O - s_{oo}^O}{s_{oo}^c - s_{oo}^c})e_o^*. \n\\end{cases} \\tag{OS.78}\n\\]\n\nIn equation (OS.78) Curve Io is valid for the region where the originator does not invest much effort and the contributor is the quality leader; Curve IIo is valid for the region where the originator puts substantial effort and becomes the quality leader. The originator chooses his optimal effort level solving (OS.77) by comparing the maximizers of these two curves.\n\nNow, for the proof of Proposition 6, we first explore the case where \\( \\beta_c \\) is small. We start by determining the behavior of \\( c_{oc}^O \\) and \\( e_o^* \\) as \\( \\beta_c \\to 0 \\). Define \\( z = 1/\\beta_c \\), i.e., as \\( \\beta_c \\to 0 \\), \\( z \\to \\infty \\). Further define \\( k, p, p, k \\in \\mathbb{R} \\) as the values that satisfy\n\n\\[\n\\lim_{z \\to \\infty} \\frac{c_{oc}^O}{z^k} = K_1 \\quad \\text{and} \\quad \\lim_{z \\to \\infty} \\frac{e_o^*}{z^p} = K_2, \\tag{OS.79}\n\\]\n\nwhere \\( K_1, K_2 \\in \\mathbb{R} \\) are constants. In other words, as \\( z \\to \\infty \\), \\( c_{oc}^O \\) is in the order of \\( z^k \\), and \\( e_o^* \\) is in the order of \\( z^p \\) \\((O(z^k) \\text{ and } O(z^p) \\text{ in standard notation, respectively})\\). Our goal is determining the values of \\( k \\) and \\( p \\) in equilibrium, which will tell us the behavior of \\( c_{oc}^O \\) and \\( e_o^* \\) as \\( z \\to \\infty \\), i.e., as \\( \\beta_c \\to 0 \\).\n\nFirst suppose \\( p < k \\). Looking at the first order condition of the contributor’s profit with respect to \\( e_c \\), in the two possible regions in the contributor’s profit curve as given by (OS.55), first, in the first region, by (OS.57)-(OS.59), plugging in \\( c_{oc}^O = O(z^k) \\) and \\( e_o^* = O(z^p) \\), and collecting the terms in powers of \\( z \\), we find that the first order condition can be written as\n\n\\[\nE_1 z^{4k-1} + E_2 z^k + Y_1(z) = 0 \\tag{OS.80}\n\\]\n\nOS.23\nwhere $E_1, E_2 \\in \\mathbb{R}$ and $Y_1(z)$ is a polynomial in $z$, with terms in orders of $z^{3p}$, $z^{2p+k}$, $z^{3p+k-1}$, $z^{p+2k}$, $z^{2p+2k-1}$ and $z^{3k+p-1}$. Notice that as $z \\to \\infty$, the term in the order of $z^{3p}$ in $Y_1(z)$ will be less than $E_2z^{3k}$ in absolute value, and all the other terms in $Y_1(z)$ will be less than $E_1z^{4k-1}$ in absolute value.\n\nNow, as $z \\to \\infty$, (OS.80) has to hold for all $z$ values. But this is not possible if $4k - 1 \\neq 3k$, because, in that case, the larger of $E_1z^{4k-1}$ and $E_2z^{3k}$ in absolute value will dominate all other terms for sufficiently large $z$ and (OS.80) will never be satisfied. Therefore, in equilibrium $E_1z^{4k-1}$ and $E_2z^{3k}$ have to cancel each other, i.e., $4k - 1 = 3k$ has to hold, which in turn implies that $k = 1$. Repeating the same analysis for the second region, this time using (OS.63)-(OS.65), we again find that the first order condition is equivalent to (OS.80) as described above, and hence it again follows that $k = 1$.\n\nSecond suppose $p > k$. In this case, again utilizing the first order condition for the first region as given in (OS.57)-(OS.59), we find that the first order condition can be written as\n\n$$E_3z^{3p+k-1} + E_4z^{3p} + Y_2(z) = 0 \\quad \\text{(OS.81)}$$\n\nfor $E_3, E_4 \\in \\mathbb{R}$ and $Y_2(z)$ is a polynomial in $z$, with again terms in orders of $z^{3p}$, $z^{2p+k}$, $z^{3p+k-1}$, $z^{p+2k}$, $z^{2p+2k-1}$ and $z^{3k+p-1}$. Notice in this case that as $z \\to \\infty$, the term in the order of $z^{3k}$ in $Y_2(z)$ will be less than $E_4z^{3p}$ and all the other terms in $Y_2(z)$ will be less than $E_3z^{3p+k-1}$ in absolute value. Therefore, with the same argument as above, we conclude that $3p + k - 1 = 3p$ must hold, which implies that $k = 1$.\n\nOnce again repeating the same analysis for the second region using (OS.63)-(OS.65) and following identical steps, we find that if the global optimum $e^*_c$ is in this region, $k = 1$ follows.\n\nIn summary, we have so far shown that if $p \\neq k$, then $k = 1$ holds, i.e., $e^*_c$ is in the order of $z(= 1/\\beta_c)$. This means that we can write\n\n$$e^*_c = \\kappa_0 + \\kappa_1 z + O(1/z), \\quad \\text{(OS.82)}$$\n\nfor constants $\\kappa_1, \\kappa_2 \\in \\mathbb{R}$.\n\nNow let us look at the optimization problem of the originator, as given in (OS.77)-(OS.78). Taking the total derivative of the originator’s profit with respect to $e_o$, we obtain the first order condition as\n\n$$\\frac{d\\Pi^O_o(e_o, e^*_c(e_o))}{de_o} \\bigg|_{e_o=e^*_o} = \\frac{d}{de_o} \\left( \\hat{\\Pi}^O_o(e_o, e^*_c(e_o)) - \\frac{1}{2} \\beta_0 e_o^2 \\right) \\bigg|_{e_o=e^*_o} = \\frac{\\partial \\hat{\\Pi}^O_o(e_o, e^*_c(e_o))}{\\partial e_o} \\bigg|_{e_o=e^*_o} + \\frac{\\partial \\hat{\\Pi}^O_o(e_o, e^*_c(e_o))}{\\partial e^*_c} \\cdot \\frac{de^*_c(e_o)}{de_o} \\bigg|_{e_o=e^*_o} - \\beta_0 e^*_o = 0. \\quad \\text{(OS.83)}$$\n\nNow we know by Lemma OS.3 that the contributor’s optimal effort will be the local maximizer of one of the two curves given in (OS.55). Therefore, we know that\n\n$$\\frac{\\partial}{\\partial e_o} \\hat{\\Pi}^O_o(e_o, e_c) \\bigg|_{e_o=e^*_o(e_c)} - \\beta_0 e^*_c(e_o) = 0. \\quad \\text{(OS.84)}$$\nThen by the implicit function function theorem\n\\[\n\\frac{d\\tilde{c}^O_o(e_o, e_c)}{d\\tilde{e}_o} = -\\frac{\\partial^2}{\\partial e_c \\partial e_o} \\tilde{\\Pi}^O(e_o, e_c)\n\\] \n(OS.85)\n\nPlugging (OS.85) in (OS.83), we then obtain\n\\[\n\\frac{\\partial \\tilde{\\Pi}^O(e_o, e_c^o(e_o))}{\\partial e_o} \\bigg|_{e_o = e_o^*} - \\frac{\\partial \\tilde{\\Pi}^O(e_o, e_c^o(e_o))}{\\partial e_c^o} \\bigg|_{e_o = e_o^*} - \\beta_c e_c^o = 0.\n\\] \n(OS.86)\n\nNow, by (OS.55) and (OS.78), \\(\\tilde{\\Pi}^O\\) and \\(\\tilde{\\Pi}^O_c\\) can take two possible functional forms each, depending on whether the originator or the contributor is the quality leader. For each of these two cases, plugging in the corresponding functional forms for \\(\\tilde{\\Pi}^O\\) and \\(\\tilde{\\Pi}^O_c\\), and calculating the partial derivatives needed in (OS.86), substituting in and calculating (OS.86) and finally substituting the functional form \\(e_c^o = \\kappa_0 + \\kappa_1 z + O(1/z)\\), and that \\(e_o^O\\) is in the order of \\(z^p\\), we find that\\(^3\\)\n\\[\nK_1 - \\beta_o e_o^O = 0,\n\\] \n(OS.87)\n\nfor some \\(K_1 \\in \\mathbb{R}\\) for both cases of \\(p > k\\) and \\(p < k\\). That is, for all cases, if \\(p \\neq k\\), then it follows that \\(e_o^O\\) is a constant, which means that \\(p = 0\\). Combining this with the finding that \\(k = 1\\) holds for \\(p \\neq k\\), it follows that the only possible outcome for the case \\(p \\neq k\\) is \\(p < k\\) and that \\(p = 0\\) and \\(k = 1\\).\n\nFinally suppose \\(p = k\\). Then plugging in \\(e_c^o\\) and \\(e_o^O\\) are both in the order of \\(z^p\\) and once again carrying out the calculations as above, we find that (OS.87) is satisfied, i.e., in this case \\(p = k = 0\\) has to hold. Note however that \\(e_c^o\\) has to satisfy the first order condition given in (OS.84) for one of the two curves given in (OS.55). Now suppose in equilibrium, the contributor’s quality is lower than the originator’s quality. Then, given \\(e_c^o\\), by (OS.55), \\((s_{cc}^O - s_{co}^O)e_c^o < (s_{oo}^O - s_{co}^O)e_o^O\\) must hold. But in that case, again by (OS.55), for small enough \\(\\beta_c\\), there exists \\((s_{cc}^O - s_{co}^O)e_c^o > (s_{oo}^O - s_{co}^O)e_o^O\\) such that\n\\[\n\\Pi^O_c(e_c|e_o^O) > \\Pi^O_e(e_c|e_o^O),\n\\] \n(OS.88)\n\nthat is, the contributor cannot have lower quality than the originator in equilibrium. So the contributor is the quality leader and his profit can be written as in (OS.63) and by (OS.84) the first order condition for the contributor’s maximization problem can be written as\n\\[\n\\frac{d\\Pi^O_c(e_o, e_c)}{d e_c} = \\frac{Q_o^O (24(Q_c^O)^2 (4s_{cc}^O - s_{co}^O) + 8s_{cc}^O (4Q_c^O - Q_o^O)^2 - 4(13s_{cc}^O - s_{co}^O)Q_c^O (4Q_c^O - Q_o^O)) - \\beta_c e_c}{(4Q_c^O - Q_o^O)^3} > \\frac{8Q_o^O (Q_c^O - Q_o^O)^2}{(4Q_c^O - Q_o^O)^3} - \\beta_c e_c.\n\\] \n(OS.89)\n\nFrom (OS.89), we can see that the first order condition becomes positive as \\(\\beta_c \\to 0\\), and hence, it cannot\n\n\\(^3\\)The exact expressions that are obtained after these calculations are very large, so we skip them here. These expressions are available from the authors upon request.\nbe satisfied as $\\beta_c \\to 0$; this is because the first term in (OS.89) converges to a strictly positive constant since $e_o^{O*}$ and $e_c^{O*}$ converge to constants (since $k = p = 0$) while the second term converges to zero as $\\beta_c \\to 0$. In conclusion, in equilibrium, $k = p = 0$ cannot hold either and the only possible case is $k = 1$ and $p = 0$, that is,\n\n$$e_c^{O*} = \\kappa_0 + \\kappa_1 z + O\\left(\\frac{1}{z}\\right) \\text{ and } e_o^{O*} = \\kappa_2 + O\\left(\\frac{1}{z}\\right).$$\n\n(OS.90)\n\nBut then, calculating the service qualities of the originator and the contributor respectively, we obtain\n\n$$Q_o^O = s_{oo}^O e_o^{O*} + s_{oc}^O e_c^{O*} = s_{oo}^O \\kappa_1 z + s_{oc}^O \\kappa_2 + s_{oc}^O \\kappa_0 + O\\left(\\frac{1}{z}\\right)$$\n\n$$\\leq Q_c^O = s_{co}^O e_o^{O*} + s_{cc}^O e_c^{O*} = s_{cc}^O \\kappa_1 z + s_{co}^O \\kappa_2 + s_{cc}^O \\kappa_0 + O\\left(\\frac{1}{z}\\right),$$\n\n(Os.91)\n\nsince $s_{cc}^O > s_{oc}^O$. Hence as $z \\to \\infty$, i.e., as $\\beta_c \\to 0$, the contributor is the quality leader. Therefore, the contributor’s and the originator’s profit functions equal to Curve Iic in (OS.55) and Curve Io defined in (OS.78). Therefore, substituting (OS.90) for $\\kappa_0, \\kappa_1, \\kappa_2 \\in \\mathbb{R}$, into the first order conditions for Curve Iic for the contributor as given in (OS.64)-(OS.65) and those for Curve Io for the originator, and collecting the terms in powers of $z$, we obtain the two first order conditions that need to be satisfied in equilibrium as polynomials of $z$. Since these two conditions have to be satisfied for all $\\beta_c$ values, their lead coefficients have to be identically zero. Thus, equating the lead coefficients to zero, we find that the following two equations in two unknowns have to be satisfied by $\\kappa_1$ and $\\kappa_2$:\n\n$$\\frac{4(s_{cc}^O - s_{oc}^O)s_{cc}^2}{(4s_{cc}^O - s_{oc}^O)^2} - \\kappa_1 = 0,$$\n\n$$- 3s_{cc}^O s_{oc}^O (s_{cc}^O - s_{oc}^O)(4s_{oo}^O - s_{oc}^O)(4(s_{cc}^O)^2(s_{cc}^O - s_{oc}^O) - \\kappa_1(4s_{cc}^O - s_{oc}^O)^2)$$\n\n$$\\quad \\cdot 4(4s_{cc}^O - s_{oc}^O)^3(3(s_{cc}^O)^2(s_{cc}^O - s_{oc}^O) - \\kappa_1(4s_{cc}^O - s_{oc}^O)^2)$$\n\n$$\\quad \\cdot s_{cc}^O (s_{cc}^O)^2(4s_{cc}^O - 7s_{oc}^O) + (s_{oc}^O)^2 s_{cc}^O (s_{oc}^O + 2s_{cc}^O)$$\n\n$$\\quad \\cdot (4s_{cc}^O - s_{oc}^O)^3 \\beta_o = 0. \\quad \\text{(OS.92)}$$\n\nSolving the system (OS.92), we obtain\n\n$$\\kappa_1 = \\frac{4(s_{cc}^O - s_{oc}^O)s_{cc}^2}{(4s_{cc}^O - s_{oc}^O)^2} ,$$\n\n(OS.93)\n\n$$\\kappa_2 = \\frac{s_{cc}^O (s_{cc}^O)^2(4s_{cc}^O - 7s_{oc}^O) + (s_{oc}^O)^2 s_{cc}^O (s_{oc}^O + 2s_{cc}^O)}{(4s_{cc}^O - s_{oc}^O)^3 \\beta_o} .$$\n\n(OS.94)\n\nNote that $\\kappa_1 \\geq 0$. If $\\kappa_2 < 0$, it corresponds to the boundary solution of $e_o^{O*} = 0$. Hence,\n\n$$\\lim_{\\beta_c \\to 0} e_o^{O*} = \\max \\left( \\frac{s_{cc}^O (s_{cc}^O)^2(4s_{cc}^O - 7s_{oc}^O) + (s_{oc}^O)^2 s_{cc}^O (s_{oc}^O + 2s_{cc}^O)}{(4s_{cc}^O - s_{oc}^O)^3 \\beta_o}, 0 \\right) .$$\n\n(OS.95)\n\nFinally, substituting the equilibrium effort levels $e_o^{O*}$ and $e_c^{O*}$ into the equilibrium prices and consumer\n\n---\n\n4The first order condition expressions for the originator are very large and hence omitted here. These expressions are available from the authors upon request.\nequilibrium outcomes presented in Proposition 5 and Lemma OS.2, respectively, and taking the limit, we then obtain the consumer market demand outcome in equilibrium. This completes the proof of Proposition 6.\n\nSimilarly, for Proposition 7, we start by determining the behavior of $e^O_c$ and $e^O_o$ as $\\beta_c \\to \\infty$. Define $q, u \\in \\mathbb{R}$ as the values that satisfy\n\n$$\\lim_{\\beta_c \\to \\infty} \\frac{e^O_c}{\\beta_c^3} = K_3 \\quad \\text{and} \\quad \\lim_{\\beta_c \\to \\infty} \\frac{e^O_o}{\\beta_c^4} = K_4,$$\n\n(OS.96)\n\nwhere $K_3, K_4 \\in \\mathbb{R}$ are constants. In other words, as $\\beta_c \\to \\infty$, $e^O_c$ is in the order of $\\beta_c^q$ and $e^O_o$ is in the order of $\\beta_c^u$, or equivalently, $O(\\beta_c^q)$ and $O(\\beta_c^u)$ in standard notation respectively. We aim to determine the values of $q$ and $u$ in equilibrium, in order to tell the behavior of $e^O_c$ and $e^O_o$ as $\\beta_c \\to \\infty$.\n\nFirst, suppose that $q < u$. Looking at the first order condition of the contributor’s profit with respect to $e_c$, in the two possible regions of the contributor’s profit curve as given by (OS.55), first, in the first region, by (OS.57)-(OS.59), plugging in $e^O_c = O(\\beta_c^q)$ and $e^O_o = O(\\beta_c^u)$, and collecting the terms in powers of $\\beta_c$, we find that the first order condition can be written as\n\n$$E_5 \\beta_c^{3u} + E_6 \\beta_c^{3u+q+1} + Y_3(\\beta_c) = 0$$\n\n(OS.97)\n\nwhere $E_5, E_6 \\in \\mathbb{R}$ and $Y_3(\\beta_c)$ is a polynomial in $\\beta_c$, with terms in orders of $\\beta_c^{3q}, \\beta_c^{2q+u}, \\beta_c^{q+2u}, \\beta_c^{4q+1}, \\beta_c^{3q+u+1}$ and $\\beta_c^{2(q+u)+1}$. Notice that as $\\beta_c \\to \\infty$, the term in the order of $\\beta_c^{3u}$ in $Y_3(\\beta_c)$ will be less than $E_5 \\beta_c^{3u}$ in absolute value, and all the other terms in $Y_3(\\beta_c)$ will be less than $E_6 \\beta_c^{3u+q+1}$ in absolute value.\n\nNow, as $\\beta_c \\to \\infty$, (OS.97) has to hold for all $\\beta_c$ values. But this is not possible if $3u \\neq 3u + q + 1$, because, in that case, the larger of $E_5 \\beta_c^{3u}$ and $E_6 \\beta_c^{3u+q+1}$ in absolute value will dominate all other terms for sufficiently large $\\beta_c$ and (OS.97) will never be satisfied. Therefore, in equilibrium $E_5 \\beta_c^{3u}$ and $E_6 \\beta_c^{3u+q+1}$ have to cancel each other, i.e., $3u = 3u + q + 1$ has to hold, which in turn implies that $q = -1$. Repeating the same analysis for the second region, this time using (OS.63)-(OS.65), we again find that the first order condition is equivalent to (OS.97) as described above, and hence it again follows that $q = -1$.\n\nSecond suppose $q > u$. In this case, again utilizing the first order condition for the first region as given in (OS.57)-(OS.59), we find that the first order condition can be written as\n\n$$E_7 \\beta_c^{3q} + E_8 \\beta_c^{4q+1} + Y_4(\\beta_c) = 0$$\n\n(OS.98)\n\nfor $E_7, E_8 \\in \\mathbb{R}$ and $Y_4(\\beta_c)$ is a polynomial in $\\beta_c$, with again terms in orders of $\\beta_c^{3u}, \\beta_c^{2u+q}, \\beta_c^{u+2q}, \\beta_c^{u+3q+1}, \\beta_c^{(u+q)1}$ and $\\beta_c^{3u+q+1}$. Notice in this case that as $\\beta_c \\to \\infty$, the term in the order of $\\beta_c^{3u}$ in $Y_4(\\beta_c)$ will be less than $E_7 \\beta_c^{3q}$ and all the other terms in $Y_4(\\beta_c)$ will be less than $E_8 \\beta_c^{4q+1}$ in absolute value. Therefore, with the same argument as above, we conclude that $3q = 4q + 1$ must hold, which implies that $q = -1$. Once again repeating the same analysis for the second region using (OS.63)-(OS.65) and following identical steps, we find that if the global optimum $e^O_c$ is in this region, $q = -1$ follows.\n\nIn summary, we have so far shown that if $r \\neq q$, then $q = -1$ holds, i.e., $e^O_c$ is in the order of $1/\\beta_c$.\nThis means that we can write\n\\[ e_c^{O*} = \\kappa_3/\\beta_c + O(1/\\beta_c^2), \\tag{OS.99} \\]\nfor constants \\( \\kappa_3 \\in \\mathbb{R} \\).\n\nTo determine the behavior of the originator’s effort investment \\( e_o^{O*} \\), note that by (OS.55) and (OS.78), \\( \\bar{\\Pi}_o^O \\) and \\( \\bar{\\Pi}_o^\\circ \\) can take two possible functional forms each, depending on who is the quality leader, either the originator or the contributor. Following the same steps in part (i), calculating (OS.86) and substituting the functional form \\( e_c^{O*} = \\kappa_3/\\beta_c + O(1/\\beta_c^2) \\) into the first order conditions of \\( e_o^O \\), which is obtained by taking the derivative of \\( \\Pi^O \\) in (OS.77) and (OS.78) with respect to \\( e_o^O \\), and that \\( e_o^{O*} \\) is in the order of \\( \\beta_c^u \\), we find that\n\\[ K_2 - \\beta_o e_o^{O*} = 0, \\tag{OS.100} \\]\nfor some \\( K_2 \\in \\mathbb{R} \\) for both cases of \\( u > q \\) and \\( u < q \\). That is, for all cases, if \\( u \\neq q \\), then it follows that \\( e_o^{O*} \\) is a constant, which means that \\( u = 0 \\). Combining this with the finding that \\( q = -1 \\) holds for \\( u \\neq q \\), it follows that the only possible outcome for the case \\( u \\neq q \\) is \\( u > q \\) and that \\( u = 0 \\) and \\( q = -1 \\), i.e., the originator becomes the quality leader in equilibrium.\n\nFinally suppose \\( u = q \\). Then plugging in \\( e_c^{O*} \\) and \\( e_o^{O*} \\) are both in the order of \\( \\beta_c^u \\) and once again carrying out the calculations as above, we find that (OS.100) is satisfied, i.e., in this case \\( u = q = 0 \\) has to hold. Note however that \\( e_o^{O*} \\) has to satisfy the first order condition given in (OS.84) for one of the two curves given in (OS.55). In both curves, as \\( \\beta_c \\to \\infty \\), the contributor’s first order condition (OS.84) becomes negative for \\( u = q = 0 \\), and hence, it cannot be satisfied as \\( \\beta_c \\to \\infty \\). In conclusion, in equilibrium, \\( u = q = 0 \\) cannot hold either and the only possible case is \\( u = 0 \\) and \\( q = -1 \\), that is,\n\\[ e_c^{O*} = \\kappa_3/\\beta_c + O \\left( 1/\\beta_c^2 \\right) \\quad \\text{and} \\quad e_o^{O*} = \\kappa_4 + \\kappa_5/\\beta_c + O \\left( 1/\\beta_c^2 \\right), \\tag{OS.101} \\]\nfor \\( \\kappa_3, \\kappa_4, \\kappa_5 \\in \\mathbb{R} \\). Then, calculating the service qualities of the originator and the contributor respectively, we obtain\n\\[ Q_o^O = s_{oo}^O e_o^{O*} + s_{oc}^O e_c^{O*} = s_{oo}^O \\kappa_4 + (s_{oc}^O \\kappa_3 + s_{oo}^O \\kappa_5)/\\beta_c + O \\left( 1/\\beta_c^2 \\right) \\geq Q_c^O = s_{oc}^O e_c^{O*} + s_{cc}^O e_c^{O*} = s_{oc}^O \\kappa_4 + (s_{cc}^O \\kappa_3 + s_{co}^O \\kappa_5)/\\beta_c + O \\left( 1/\\beta_c^2 \\right), \\tag{OS.102} \\]\n\nsince \\( s_{oo}^O > s_{co}^O \\). Hence as \\( \\beta_c \\to \\infty \\), the originator is the quality leader. Therefore, the contributor’s and the originator’s profit functions equal to Curve Ic in (OS.55) and Curve IIo defined in (OS.78), respectively. Substituting (OS.101) for \\( \\kappa_3, \\kappa_4, \\kappa_5 \\in \\mathbb{R} \\), into the first order conditions for Curve IIc for the contributor as given in (OS.58)-(OS.59) and those for Curve IIo for the originator,\\(^5\\) and collecting the terms in powers of \\( \\beta_c \\), we obtain the two first order conditions that need to be satisfied in equilibrium as polynomials of \\( \\beta_c \\). Because these two conditions have to be satisfied for all \\( \\beta_c \\) values, their lead coefficients have to be identically zero. Thus, following the same steps in the proof of part (i) by equating the lead coefficients to\n\n\\(^5\\)The first order condition expressions for the originator are again very large and hence omitted. These expressions are also available from the authors upon request.\nzero, we find that the following two equations in two unknowns have to be satisfied by \\( \\kappa_3 \\) and \\( \\kappa_4 \\):\n\n\\[\n\\frac{(s_{oo}^O)^2 s_{cc}^O (4s_{oo}^O - 7s_{co}^O) + (s_{co}^O)^2 s_{oc}^O (2s_{oo}^O + s_{co}^O)}{(4s_{oo}^O - s_{co}^O)^3} - \\kappa_3 = 0,\n\\]\n\n\\[\n4 (s_{oo}^O)^2 (s_{oo}^O - s_{co}^O) - \\kappa_4 \\beta_o = 0. \\tag{OS.103}\n\\]\n\nSolving the system (OS.103), we obtain\n\n\\[\n\\kappa_3 = \\frac{(s_{oo}^O)^2 s_{cc}^O (4s_{oo}^O - 7s_{co}^O) + (s_{co}^O)^2 s_{oc}^O (2s_{oo}^O + s_{co}^O)}{(4s_{oo}^O - s_{co}^O)^3}, \\tag{OS.104}\n\\]\n\n\\[\n\\kappa_4 = \\frac{4 (s_{oo}^O)^2 (s_{oo}^O - s_{co}^O)}{(4s_{oo}^O - s_{co}^O)^2 \\beta_o}. \\tag{OS.105}\n\\]\n\nIf \\( \\kappa_3 < 0 \\), then it corresponds to the boundary solution of \\( e_{O*}^c = 0 \\). Therefore, we conclude that\n\n\\[\n\\lim_{\\beta_c \\to \\infty} e_{O*}^c = \\frac{4 (s_{oo}^O)^2 (s_{oo}^O - s_{co}^O)}{(4s_{oo}^O - s_{co}^O)^2 \\beta_o}. \\tag{OS.106}\n\\]\n\nLastly, we replace these equilibrium effort levels \\( e_{O*}^c \\) and \\( e_{O*}^o \\) into the equilibrium prices and consumer equilibrium outcomes presented in Proposition 5 and Lemma OS.2, respectively, and take the limit of \\( \\beta_c \\to \\infty \\) to obtain the consumer market demand outcome in equilibrium, which completes the proof. ■\n\n**Proof of Proposition 8:** Define\n\n\\[\n\\bar{s} = \\frac{18 s_{cc}^O (s_{cc}^O - s_{oc}^O)}{4 s_{cc}^O - s_{oc}^O)^2 \\sqrt{s_{oc}^O s_{cc}^O}. \\tag{OS.107}\n\\]\n\nTechnically, we show that there exists \\( \\underline{\\beta} > \\bar{\\beta} > 0 \\) such that if \\( s_{cc}^P < \\bar{s} \\), and \\( s_{cc}^O > s_{cc}^O \\), then\n\n(i) If \\( \\beta_c < \\bar{\\beta} \\), an open source strategy is optimal for the originator. In equilibrium, the contributor is the quality leader.\n\n(ii) If \\( \\beta_c > \\bar{\\beta} \\) then a proprietary strategy is optimal for the originator. In this case, the originator chooses to push the contributor out of the market and serves as a monopolist for services as well as the product.\n\nWe consider the cases as \\( \\beta_c \\to 0 \\) (part (i)) and \\( \\beta_c \\to \\infty \\) (part (ii)). We have already calculated the equilibrium effort levels for the originator and the contributor for these cases for open source strategy, in the proof of Propositions 6 and 7. In this proof, we will utilize these findings in order to calculate equilibrium originator profit levels for the open source strategy and compare them to the corresponding profits under the proprietary strategy to determine the originator’s best software strategy choice.\n\nFor part (i), to calculate the originator profits under the open source strategy, plugging (OS.93) and (OS.94) into (OS.90), substituting these in turn into \\( \\Pi_o^c(\\cdot) \\) as given in (OS.77) with \\( \\Pi_o^O(\\cdot) \\) corresponding to Curve Io as defined in (OS.78) and collecting the terms of \\( z \\), or equivalently \\( 1/\\beta_c \\), we obtain the equilibrium\nprofit for the originator for the open source strategy as\n\\[\n\\Pi^O_o (e^{O*}) = \\frac{4s^O_{oc}(s^O_{cc})^3(s^O_{co} - s^O_{oc})^2}{\\beta_c(4s^O_{cc} - s^O_{oc})^4} + \\frac{(s^O_{oc})^2(4s^O_{cc} - 7s^O_{oc}) + (s^O_{oc})^2(s^O_{cc} + 2s^O_{oc})^2}{2\\beta_o(4s^O_{cc} - s^O_{oc})^6} + O (\\beta_c). \\tag{OS.108)\n\\]\n\nFor the proprietary strategy on the other hand, plugging the optimal effort expressions given in Propositions 2 and 3 into the originator’s profit expression in (OS.20), we obtain the originator’s optimal profit in equilibrium as\n\\[\n\\Pi^P_o (\\bar{e}^{P*}) = \\left\\{ \\begin{array}{ll}\n\\frac{(5s^P_{oo} + 4s^P_{cc})^2}{2252\\beta_o} + \\frac{(s^P_{co})^2}{32\\beta_o}, & \\text{if } \\beta_c < \\bar{r}, \\\\\n\\frac{(s^P_{co})^2}{81\\beta_o}, & \\text{if } \\beta_c \\geq \\bar{r};\n\\end{array} \\right.\n\\tag{OS.109)\n\\]\nwhere \\(\\bar{r}\\) is as defined in (OS.21). Consequently, for sufficiently small \\(\\beta_c\\), by Proposition 3 and (OS.109), we have \\(\\bar{e}^{P*} = \\frac{4s^P_{oo} + 5s^P_{cc}}{36\\beta_o}\\) and \\(\\Pi^P_o (\\bar{e}^{P*}) = \\frac{(s^P_{co})^2}{81\\beta_c} + \\frac{(s^P_{co})^2}{2952\\beta_o}\\). As a result, for sufficiently small \\(\\beta_c\\), \\(\\Pi^O_o (\\bar{e}^{O*}) > \\Pi^P_o (\\bar{e}^{P*})\\) if and only if the coefficient of \\(1/\\beta_c\\) in the originator’s profit expression for the open-source case is larger than the corresponding coefficient for the proprietary case, i.e.,\n\\[\n\\Pi^O_o (\\bar{e}^{O*}) = \\frac{4s^O_{oc}(s^O_{cc})^3(s^O_{co} - s^O_{oc})^2}{(4s^O_{cc} - s^O_{oc})^4} > \\Pi^P_o (\\bar{e}^{P*}) = \\frac{(s^P_{co})^2}{81}. \\tag{OS.110)\n\\]\nSimplifying (OS.110), we obtain the desired condition as\n\\[\ns^P_{cc} < \\frac{18s^O_{oc}(s^O_{co} - s^O_{oc})}{(4s^O_{cc} - s^O_{oc})^2} \\sqrt{s^O_{oc}s^O_{cc}}. \\tag{OS.111)\n\\]\nThis completes the proof of part (i).\n\nSimilarly, for part (ii), plugging (OS.104) and (OS.105) into (OS.101), substituting these in turn into \\(\\Pi^O_o (\\cdot)\\) as given in (OS.77) with \\(\\Pi^O_o (\\cdot)\\) corresponding to Curve Io as defined in (OS.78) and collecting the terms of \\(\\beta_c\\), we obtain the equilibrium profit for the originator for the open source strategy as\n\\[\n\\Pi^O_o (e^{O*}) = \\frac{8(s^O_{oo})^4(s^O_{oc} - s^O_{co})^2}{(4s^O_{oo} - s^O_{co})^4\\beta_o} + O (1/\\beta_c). \\tag{OS.112)\n\\]\n\nFor the proprietary strategy on the other hand, from Propositions 2 and 3, and equation (OS.109), we have \\(\\bar{e}^{P*} = s^P_{oo}/(\\beta_o)\\) and \\(\\Pi^P_o (\\bar{e}^{P*}) = (s^P_{oo})^2/(32\\beta_o)\\). Comparing these two profit expressions, since \\(s^P_{oo} > s^O_{co}\\) for sufficiently large \\(\\beta_c\\), it follows that\n\\[\n\\Pi^P_o (\\bar{e}^{P*}) - \\Pi^O_o (\\bar{e}^{O*}) = \\frac{(s^P_{oo})^2}{32\\beta_o} - \\left( \\frac{8(s^O_{oo})^4(s^O_{oc} - s^O_{co})^2}{(4s^O_{oo} - s^O_{co})^4\\beta_o} + O (1/\\beta_c) \\right)\n= \\frac{(s^O_{oo})^2}{32(4s^O_{oo} - s^O_{co})^4\\beta_o} \\left( 16s^O_{oo}s^O_{co} (10s^O_{oo}(s^O_{oc} - s^O_{co}) + 6(s^O_{oo})^2 - (s^O_{co})^2) + (s^O_{co})^4 \\right) - O (1/\\beta_c) > 0. \\tag{OS.113)\n\\]\nThis completes the proof. ■\n\n**Proof of Proposition 9:** Technically, we show that there exist bounds \\(\\overline{\\beta}_c, \\overline{s}_{oc} > 0\\) such that if \\(s^O_{oc} < \\overline{s}_{oc}\\) and \\(\\overline{\\beta}_c < \\overline{\\beta}_c\\), then\n\n(i) \\(p^{O*}_o\\) strictly decreases in \\(\\beta_o\\), while \\(p^{O*}_o\\) strictly increases in \\(\\beta_o\\) if \\(s^O_{oo} \\geq (4/3)s^O_{co}\\) and strictly decreases\n(ii) $\\Pi^O_\\alpha$ strictly decreases in $\\beta_\\alpha$, while $\\Pi^O_\\gamma$ strictly increases in $\\beta_\\alpha$ if $s^O_{oo} \\geq 2s^O_{co}$ and strictly decreases otherwise.\n\nFirst, as we have shown in the proof of part (i) of Proposition 8, as $\\beta_c \\to 0$, in equilibrium the contributor is the quality leader. From Proposition 5, by substituting the symmetric coefficients in the price expression given in equation (OS.32) for the case in which originator is the quality leader, we find that the originator’s equilibrium service price is\n\n$$p^O_\\alpha = \\frac{2(s^O_{oc}c_c + s^O_{co}e_o)((s^O_{cc} - s^O_{oc})c_c + (s^O_{co} - s^O_{oo})e_o)}{4s^O_{cc} - 4s^O_{co} - s^O_{oo}e_o}. \\quad \\text{(OS.114)}$$\n\nNow plugging (OS.90), (OS.93) and (OS.94) in (OS.114), we obtain\n\n$$p^O_\\alpha = \\frac{4s^O_{oc}(s^O_{oc})^2(s^O_{oc} - s^O_{cc})^2}{(4s^O_{cc} - s^O_{cc})^3}\\beta^c_c + \\frac{((s^O_{oc})^2(s^O_{oo} + 3s^O_{co}) + 4s^O_{oo}s^O_{oc}(s^O_{co} - 2s^O_{cc}))}{\\beta^o_\\gamma(4s^O_{cc} - s^O_{cc})^5} \\lambda_1 + O(\\beta_c), \\quad \\text{(OS.115)}$$\n\nwhere $\\lambda_1 = (s^O_{oc})^2s^O_{oc}(2s^O_{oc} + s^O_{co}) + 4s^O_{oo}(s^O_{oc})^2(4s^O_{cc} - 7s^O_{cc})$. Differentiating (OS.115) with respect to $\\beta_\\alpha$ and taking the limit as $s^O_{oc} \\to 0$, we obtain\n\n$$\\lim_{s^O_{oc} \\to 0} \\frac{dp^O_\\alpha}{d\\beta_\\alpha} = \\lim_{s^O_{oc} \\to 0} \\frac{((s^O_{oc})^2(s^O_{oo} + 3s^O_{co}) + 4s^O_{oo}s^O_{oc}(s^O_{co} - 2s^O_{cc}))}{\\beta^2_o(4s^O_{cc} - s^O_{cc})^5} \\lambda_1 + O(\\beta_c) = -\\frac{(s^O_{oo})^2}{64\\beta^2_o} + O(\\beta_c) < 0, \\quad \\text{(OS.116)}$$\n\nas $\\beta_c \\to 0$. That is, when $\\beta_c$ and $s^O_{oc}$ are sufficiently small, $p^O_\\alpha$ decreases in $\\beta_\\alpha$, i.e., there exist $\\overline{\\beta_c}, \\overline{s_{oc}} > 0$ such that if $\\beta_c < \\overline{\\beta_c}$ and $s^O_{oc} < \\overline{s_{oc}}$, then $p^O_\\alpha$ decreases in $\\beta_\\alpha$.\n\nSimilarly, for $p^O_\\gamma$, again by substituting the symmetric coefficients in the price expression given in equation (OS.33) in Proposition 5, we find that the contributor’s equilibrium service price is\n\n$$p^O_\\gamma = \\frac{(s^O_{oo}c_c + s^O_{co}e_o)((s^O_{cc} - s^O_{oc})c_c + (s^O_{co} - s^O_{oo})e_o)}{4s^O_{cc} - s^O_{cc}e_c + (4s^O_{co} - s^O_{oo})e_o}. \\quad \\text{(OS.117)}$$\n\nAgain plugging in (OS.90), (OS.93) and (OS.94),\n\n$$p^O_\\gamma = \\frac{8(s^O_{oc})^3(s^O_{cc} - s^O_{oc})^2}{(4s^O_{cc} - s^O_{cc})^3}\\beta^c_c - \\frac{2(s^O_{oc}s^O_{co}(2s^O_{cc} - s^O_{cc}) + (s^O_{co})^2(3s^O_{co} - 4s^O_{co}))}{\\beta^o_\\gamma(4s^O_{cc} - s^O_{cc})^5} \\lambda_2 + O(\\beta_c), \\quad \\text{(OS.118)}$$\n\nwhere $\\lambda_2 = s^O_{oc}(s^O_{cc})^2(4s^O_{cc} - 7s^O_{cc}) + (s^O_{oc})^2s^O_{oc}(s^O_{cc} + 2s^O_{cc})$. Differentiating (OS.118) with respect to $\\beta_\\alpha$ and again taking the limit as $s^O_{oc} \\to 0$, we obtain\n\n$$\\lim_{s^O_{oc} \\to 0} \\frac{dp^O_\\gamma}{d\\beta_\\alpha} = \\lim_{s^O_{oc} \\to 0} \\frac{2(s^O_{oc}s^O_{co}(2s^O_{cc} - s^O_{cc}) + (s^O_{co})^2(3s^O_{co} - 4s^O_{co}))}{\\beta^2_o(4s^O_{cc} - s^O_{cc})^5} \\lambda_2 + O(\\beta_c) = \\frac{s^O_{oo}(3s^O_{co} - 4s^O_{co})}{128\\beta^2_o} + O(\\beta_c). \\quad \\text{(OS.119)}$$\n\nIt follows that, for sufficiently small $\\beta_c$ and $s^O_{oc}$, $p^O_\\gamma$ is strictly increasing in $\\beta_\\alpha$ if and only if $s^O_{oo} \\geq (4/3)s^O_{co}$. This completes the proof of part (i).\nFor part (ii), taking the derivative of $\\Pi^O_c(e^O_c, e^O_c)$ given in (OS.108) with respect to $\\beta_c$ and taking the limit as $s_{oc}^O \\rightarrow 0$, we obtain\n\n$$\\lim_{s_{oc}^O \\rightarrow 0} \\frac{d\\Pi^O_c(e^O_c, e^O_c)}{d\\beta_c} = \\lim_{s_{oc}^O \\rightarrow 0} -\\frac{(s_{oo}^O(s_{cc}^O)^2(s_{oc}^O - 7s_{oc}^O) + (s_{oo}^O)^2(s_{cc}^O + s_{oc}^O))^2}{2\\beta_c^2(4s_{cc}^O - s_{oc}^O)^6} + O(\\beta_c) = \\frac{(s_{oo}^O)^2}{512\\beta_c^2} + O(\\beta_c) < 0.$$ \n\n(OS.120)\n\nConsequently, $\\Pi^O_c(e^O_c, e^O_c)$ is strictly decreasing in $\\beta_c$ for sufficiently small $\\beta_c$ and $s_{oc}^O$.\n\nFinally, substituting (OS.90), (OS.93), (OS.94), (OS.115), and (OS.118) into (OS.54), and carrying out the algebra, we obtain\n\n$$\\Pi^O_c(e^O_c, e^O_c) = \\frac{8(s_{cc}^O)^4(s_{oc}^O - s_{cc}^O)^2}{(4s_{cc}^O - s_{oc}^O)^4\\beta_c} - \\frac{4s_{cc}^O ((s_{oo}^O + 3s_{cc}^O)s_{oc}^O - 2(s_{oo}^O - 2s_{cc}^O)(s_{oc}^O + s_{cc}^O))^2}{\\beta_c^2(4s_{cc}^O - s_{oc}^O)^6} + O(\\beta_c).$$ \n\n(OS.121)\n\nOnce again, differentiating (OS.121) with respect to $\\beta_c$, and taking the limit as $s_{oc}^O \\rightarrow 0$, we find that\n\n$$\\lim_{s_{oc}^O \\rightarrow 0} \\frac{d\\Pi^O_c(e^O_c, e^O_c)}{d\\beta_c} = \\lim_{s_{oc}^O \\rightarrow 0} \\frac{4s_{cc}^O ((s_{oo}^O + 3s_{cc}^O)s_{oc}^O - 2(s_{oo}^O - 2s_{cc}^O)(s_{oc}^O + s_{cc}^O))^2}{\\beta_c^2(4s_{cc}^O - s_{oc}^O)^6} + O(\\beta_c) = \\frac{s_{oo}^O(s_{oo}^O - 2s_{cc}^O)}{128\\beta_c^2} + O(\\beta_c).$$ \n\n(OS.122)\n\nHence, for small enough $s_{oc}^O$ and $\\beta_c$, $\\Pi^O_c(e^O_c, e^O_c)$ is strictly increasing in $\\beta_c$ if only if $s_{oo}^O \\geq 2s_{cc}^O$. This completes the proof. □\n\n**Proof of Proposition 10:** For any $a > 1$, define\n\n$$\\bar{h} = \\frac{9(s_{oc}^O)^{1/2}(s_{cc}^O)^{3/2}(s_{oc}^O - s_{cc}^O)}{(4s_{cc}^O - s_{oc}^O)^2} \\left( \\sqrt{\\frac{3s_{cc}^O - s_{oc}^O}{a(s_{cc}^O - s_{oc}^O)}} - 2 \\right),$$ \n\n(OS.123)\n\nand let $\\bar{s}$ be given as in (OS.107). Technically, we show that there exists $\\bar{b} > 0$ such that for all $a > 1$, if $b < \\bar{b}$, $s_{oc}^O < s_{oc}^O < \\frac{4a - 1}{4a - 3}s_{cc}^O$, and $0 < s_{cc}^O < \\bar{s} < s_{cc}^O$, then\n\n$$W^{\\rho^*} \\bigg|_{\\beta_c = a, \\bar{s}_{cc}^O = s_{cc}^O} < W^{\\rho^*} \\bigg|_{\\beta_c = a, b, \\bar{s}_{cc}^O = s_{cc}^O}.$$ \n\n(OS.124)\n\nWe start by establishing the originator’s optimal licensing strategy for the two parameter combinations, $(\\beta_c, s_{cc}^P)$ given in the statement of the proposition. First, as given in equation (OS.111) in the proof of Proposition 8, for sufficiently small $\\beta_c$, the originator’s optimal licensing strategy is open source ($\\rho^* = O$) if $s_{cc}^P < \\bar{s}$, where $\\bar{s}$ is as defined in (OS.107), and proprietary ($\\rho^* = P$) otherwise. Therefore for all $a > 1$, for sufficiently small $b > 0$, any $s_{cc}^O > \\bar{s}$ and $0 < s_{cc}^O < \\bar{s} < s_{cc}^O < s_{cc}^O$, the policy choice is $\\rho^* = P$ if $\\beta_c = b$ and $s_{cc}^P = s_{cc}^O$; while the policy choice is $\\rho^* = O$ if $\\beta_c = a \\cdot b$ and $s_{cc}^P = s_{cc}^O$.\n\nWe next have to calculate and compare the social welfare under these two parameter combinations. First, for sufficiently small $b > 0$, $\\beta_c = b$ and $s_{cc}^P = s_{cc}^O$, $\\rho^* = P$. Then, by Proposition 3, $\\theta_H = 2/3$ and $\\theta_L = 1/2$. By substituting $\\beta_c = b$ and $s_{cc}^P = s_{cc}^O$ into the equilibrium expressions given in the proofs of\nFinally, from Proposition 6, we also obtain\n\\[ e^*_o = \\frac{5s^P_{oo} + 4s^P_{cc}}{36\\beta_o}, \\quad e^*_c = \\frac{s_h}{9\\beta_c}, \\quad (OS.125) \\]\n\n\\[ Q^o_o = \\frac{s^P_{oo}(5s^P_{oo} + 4s^P_{cc})}{36\\beta_o}, \\quad Q^o_c = \\frac{s^P_{cc}(5s^P_{cc} + 4s^P_{cc})}{36\\beta_c} + \\frac{s^2_h}{9\\beta_c}, \\quad (OS.126) \\]\n\n\\[ p^*_o = \\frac{1}{108} \\left( \\frac{(s^P_{oo} - s^P_{cc})(5s^P_{oo} + 4s^P_{cc})}{\\beta_o} - \\frac{4s^2_h}{b} \\right), \\quad \\text{and} \\quad p^*_c = \\frac{1}{108} \\left( \\frac{(s^P_{cc} - s^P_{cc})(5s^P_{cc} + 4s^P_{cc})}{\\beta_c} + \\frac{4s^2_h}{b} \\right). \\quad (OS.127) \\]\n\nPropositions 3 and 4,\n\\[ \\lim_{b \\to 0} b \\cdot W^P = \\frac{8s^O_{oo}(s^O_{cc} - s^O_{cc})^3}{(4s^O_{cc} - s^O_{cc})^4} + \\frac{8s^O_{cc}(s^O_{cc} - s^O_{cc})^2}{9(4s^O_{cc} - s^O_{cc})^2} \\sqrt{s^O_{cc}} + \\frac{2h^2}{81}. \\quad (OS.129) \\]\n\nSecond, for the case with \\( a > 1 \\), sufficiently small \\( b > 0 \\), \\( \\beta = a \\cdot b \\) and \\( s^P_{cc} = s_t \\), for \\( s_t < \\bar{s} \\), as we have stated above \\( \\rho^* = O \\) and hence, since \\( s^O_{cc} < s^O_{cc} \\) by Proposition 6, again the contributor is the quality leader, i.e., \\( Q_H = Q^O_o, Q_L = Q^O_c, p_H = p^O_c, \\) and \\( p_L = p^O_o \\). Now, from the proof of part (i) of Proposition 8, when \\( \\beta = a \\cdot b \\) is small, plugging (OS.93) and (OS.94) into (OS.90), we obtain\n\\[ e^*_c = \\kappa_0 + \\frac{4(s^O_{cc} - s^O_{cc})s^O_{cc}^2}{a \\cdot b(4s^O_{cc} - s^O_{cc})^2} + O(b) \\quad \\text{and} \\quad e^*_o = \\frac{s^O_{cc}(s^O_{cc} - s^O_{cc})^3}{(4s^O_{cc} - s^O_{cc})^3} \\beta_o + O(b). \\quad (OS.130) \\]\n\nSubstituting these equilibrium effort levels in turn into \\( Q_H = Q^O_o = e^O_{cc} + s^O_{cc}e^O_c, \\) \\( Q_L = Q^O_c = s^O_{oo}e^O_o + s^O_{cc}e^O_c, \\) and into \\( p_H = p^O_c, \\) \\( p_L = p^O_o \\) as given in Proposition 5, collecting the terms of \\( b \\) and simplifying, we obtain:\n\\[ \\lim_{b \\to 0} b \\cdot Q^O_o = \\frac{4(s^O_{cc} - s^O_{cc})(s^O_{cc})^3}{a(4s^O_{cc} - s^O_{cc})^2}, \\quad (OS.131) \\]\n\\[ \\lim_{b \\to 0} b \\cdot Q^O_c = \\frac{4s^O_{cc}(s^O_{cc} - s^O_{cc})(s^O_{cc})^2}{a(4s^O_{cc} - s^O_{cc})^2}, \\quad (OS.132) \\]\n\\[ \\lim_{b \\to 0} b \\cdot p^O_c = \\frac{8(s^O_{cc} - s^O_{cc})(s^O_{cc})^3}{a(4s^O_{cc} - s^O_{cc})^3}, \\quad (OS.133) \\]\n\\[ \\lim_{b \\to 0} b \\cdot p^O_o = \\frac{4s^O_{cc}(s^O_{cc} - s^O_{cc})(s^O_{cc})^2}{a(4s^O_{cc} - s^O_{cc})^3}. \\quad (OS.134) \\]\n\nFinally, from Proposition 6, we also obtain\n\\[ \\lim_{b \\to 0} \\theta_H = \\frac{2s^O_{cc} - s^O_{cc}}{4s^O_{cc} - s^O_{cc}}, \\quad (OS.135) \\]\nand\n\\[ \\lim_{b \\to 0} \\theta_L = \\frac{s_{oc} - s_{oc}}{4s_{cc} - s_{oc}}. \\] \\hfill (OS.136)\n\nAgain substituting (OS.130)-(OS.136) into the social welfare expression given by (3) and (4), and simplifying, we obtain\n\\[ \\lim_{b \\to 0} b \\cdot W^{O_s} = \\frac{2s_{oc}(s_{cc})^3(3s_{cc} - s_{oc})(s_{cc} - s_{oc})}{a(4s_{cc}^4 - s_{oc}^4)}. \\] \\hfill (OS.137)\n\nNow we can compare the two welfare levels. By subtracting (OS.129) from (OS.137), and simplifying, it follows that for any \\( a > 1, 0 < s_l < \\bar{s}, \\) and \\( h > 0, \\)\n\n\\[ \\lim_{b \\to 0} b \\cdot \\left( W^{O_s} \\big|_{\\beta_c = a-b, s_{cc}^p = s} - W^{O_s} \\big|_{\\beta_c = b, s_{cc}^p = s+h} \\right) = \\frac{2s_{oc}(s_{cc})^3(3s_{cc} - s_{oc})(4a-1)s_{oc} - (4a-3)s_{cc})}{a(4s_{cc}^4 - s_{oc}^4)} - \\frac{8hs_{cc}(s_{cc}^3 - s_{oc}^3)}{9(4a-1)s_{cc}^3} \\sqrt{s_{cc}s_{oc} - \\frac{2h^2}{81}}. \\] \\hfill (OS.138)\n\n(OS.138) is a quadratic function in \\( h \\) with a negative lead coefficient. Therefore, it will be positive for some \\( h > 0 \\) values if and only if its constant is positive, which is satisfied if and only if \\( s_{cc} < \\frac{4a-1}{4a-3}s_{oc}. \\) If this condition is satisfied, then (OS.138) has a unique strictly positive root \\( \\bar{h} \\) as given in (OS.123) and is positive for all \\( 0 < h < \\bar{h}, \\) i.e., (since \\( h = s_h - \\bar{s} \\)) for \\( \\bar{s} < s_h < \\bar{s} + h. \\) Hence, for all \\( a > 1, \\) there exists a \\( \\bar{b} > 0 \\) such that when \\( 0 < b < \\bar{b}, \\) and \\( 0 < s_l < \\bar{s} < s_h < \\bar{s} + \\bar{h}, \\) \\( W^{O_s} \\big|_{\\beta_c = a-b, s_{cc}^p = s_l} > W^{O_s} \\big|_{\\beta_c = b, s_{cc}^p = s_h}, \\) i.e., welfare is higher with a weak contributor than a strong contributor. This completes the proof. ■"}}},{"rowIdx":73,"cells":{"id":{"kind":"string","value":"c505a7da695b535367362527b85a7e58aa504810"},"text":{"kind":"string","value":"Binary Synchronous Communications 1 (BSC 1)\nUser Guide\nfor 2200VP, LVP, MVP, and SVP\n2200\nBinary Synchronous Communications 1\n(BSC 1) User Guide\nfor 2200VP, LVP, MVP, and SVP\n\n1st Edition — March, 1982\nCopyright © Wang Laboratories, Inc., 1982\n700-7123\n\nWang Laboratories, Inc.\nOne Industrial Avenue, Lowell, Massachusetts 01851, Tel. (917) 455-8000, TWX 710 343-6769, Telex 94-7421\nDisclaimer of Warranties\nand Limitation of Liabilities\n\nThe staff of Wang Laboratories, Inc., has taken due care in preparing this manual; however, nothing contained herein modifies or alters in any way the standard terms and conditions of the Wang purchase, lease, or license agreement by which this software package was acquired, nor increases in any way Wang's liability to the customer. In no event shall Wang Laboratories, Inc., or its subsidiaries be liable for incidental or consequential damages in connection with or arising from the use of the software package, the accompanying manual, or any related materials.\n\nNOTICE:\n\nAll Wang Program Products are licensed to customers in accordance with the terms and conditions of the Wang Laboratories, Inc. Standard Program Products License; no ownership of Wang Software is transferred and any use beyond the terms of the aforesaid License, without the written authorization of Wang Laboratories, Inc., is prohibited.\n\nWarning: This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions manual, may cause interference to radio communications. As temporarily permitted by regulation, it has not been tested for compliance with the limits for Class A computing devices pursuant to Subpart J of Part 15 of FCC Rules, which are designed to provide reasonable protection against such interference. Operation of this equipment in a residential area is likely to cause interference in which case the user at his own expense will be required to take whatever measures may be required to correct the interference.\nThis manual describes the Binary Synchronous Communications 1 (BSC 1) emulation software. The BSC 1 software provides a 2200 Series system with the capability to emulate four IBM binary synchronous protocols: 2780, 3780, 3741, and multileaving HASP. The software also provides the 2200-to-2200 protocol and the 2200 WPS mode. The 2200-to-2200 protocol is for synchronous communications between 2200 Series systems. The 2200 WPS mode is for synchronous document transfer between a 2200 Series system with 2200 Word Processing software and another Wang word processing system with synchronous communications capabilities.\n\nChapter 1 is an overview of the BSC 1 software. Chapter 2 provides instructions for configuring the software to achieve compatibility with the communications protocol in use at a remote site. Chapters 3 and 4 provide operating instructions for the emulation software.\n\nAppendix A outlines the Wang TC file format. Appendix B provides information concerning modem selection, and Appendix C discusses the information necessary for establishing a communications connection. Appendix D summarizes the BSC 1 emulator configuration process. An outline of the operation of a BSC 1 emulation is provided in Appendix E. Appendix F discusses code translation. Appendix G provides instructions for implementing software-controlled Printer Vertical Format Control.\n\nThis manual should be used in conjunction with the following manuals.\n\nWang BASIC-2 Language Reference Manual (700-4080)\nWang BASIC-2 Disk Reference Manual (700-4081)\nModel 2228/2228C/Option 62B Synchronous/Asynchronous Communications Controller User Manual (700-4670)\nTC Support Utilities 1 User Manual (700-4086)\n2200 Word Processing Software Operator's Guide (700-6937)\n\nRefer to the current Wang Corporate Publications Literature Catalog (700-5294) for information on ordering these manuals.\nCONTENTS\n\nCHAPTER 1 GENERAL INFORMATION\n\n1.1 Software Overview ................................................. 1-1\n1.2 System and Peripheral Requirements ............................. 1-2\n1.3 TC File Formatting Requirements ................................. 1-4\n1.4 Software Backup .................................................. 1-6\n1.5 Loading the BSC 1 Software ...................................... 1-7\n1.6 The BSC 1 Main Menu ............................................. 1-7\n\nCHAPTER 2 CREATING A COMMUNICATIONS CONFIGURATION\n\n2.1 Creating a New Configuration .................................... 2-1\n2.2 Selecting an Emulation ........................................... 2-1\n2.3 Specifying Valid Parameters for a New Configuration ........ 2-2\n2.4 Disk Access Methods ............................................. 2-14\n2.5 Saving a New Configuration ...................................... 2-14\n2.6 Loading a Configuration .......................................... 2-16\n2.7 Deleting or Modifying a Configuration ........................ 2-17\n\nCHAPTER 3 OPERATING A 2780, 3780, 3741, 2200-TO-2200, OR 2200 WPS EMULATION PROGRAM\n\n3.1 Initial Operator Action ............................................ 3-1\n3.2 Operational Modes ............................................... 3-2\n3.3 Displays, Prompts, and Status Messages ........................ 3-7\n3.4 Special Considerations for 2200-to-2200 Operation ........... 3-10\n3.5 Special Considerations for 2200 WPS Mode Operation ........ 3-10\n3.6 Disk File Receive Operations ................................... 3-11\n Opening a Receive File Using the Search\n Disk Access Method ............................................. 3-11\n Opening a Receive File Using\n the On Error Disk Access Method .............................. 3-13\n The Erase File Function ....................................... 3-13\n3.7 Disk File Send Operations ...................................... 3-14\n Sending a File Using the Search Disk Access Method ........ 3-14\n Sending a File Using the On Error\n Disk Access Method ............................................. 3-15\n3.8 Card Send Operations ............................................. 3-16\n3.9 Keyboard Send Operations ....................................... 3-17\n3.10 Error Messages and Recovery Techniques ....................... 3-18\n Invalid File Names (Transmission) ............................. 3-18\n Invalid File Names (Reception) ............................... 3-18\n Insufficient Disk Space (Reception) ......................... 3-19\n Insufficient File Space (Reception) ......................... 3-19\n System Errors .................................................. 3-20\n3.11 Background Operation (2200MVP or 2200LVP Processor) .... 3-20\nCHAPTER 4 OPERATING A HASP MULTILEAVING COMMUNICATIONS PROGRAM\n\n4.1 Initial Operator Action ........................................ 4-1\n4.2 The HASP Emulator Display .................................. 4-1\n4.3 The Console Output Messages Display .................... 4-5\n4.4 Console Entry and Sign-On Prompts ....................... 4-5\n4.5 Disk Send Operations ......................................... 4-7\n4.6 Disk Receive Operations ..................................... 4-9\n4.7 Card Send Operations ......................................... 4-11\n\nAPPENDICES\n\nAppendix A TC File Format ...................................... A-1\nAppendix B Modem Considerations ............................... B-1\nAppendix C Establishing a Communications Connection ..... C-1\nAppendix D BSC 1 Configuration Procedures Summary .... D-1\nAppendix E BSC 1 Operation Procedures Summary .......... E-1\nAppendix F Code Translation .................................... F-1\nAppendix G Software Printer Vertical Format Control .... G-1\n\nINDEX ............................................................... INDEX-1\n<table>\n<thead>\n<tr>\n<th>FIGURE</th>\n<th>Title</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1-1</td>\n<td>Initial Format of the BSC 1 Main Menu</td>\n<td>1-7</td>\n</tr>\n<tr>\n<td>1-2</td>\n<td>General Format of the BSC 1 Main Menu</td>\n<td>1-7</td>\n</tr>\n<tr>\n<td>1-3</td>\n<td>Sample BSC 1 Main Menu</td>\n<td>1-8</td>\n</tr>\n<tr>\n<td>2-1</td>\n<td>The Emulator Selection Menu</td>\n<td>2-1</td>\n</tr>\n<tr>\n<td>2-2</td>\n<td>Parameter Selection Menu, Part 1 (2780 Protocol)</td>\n<td>2-3</td>\n</tr>\n<tr>\n<td>2-3</td>\n<td>Parameter Selection Menu, Part 2 (2780 Protocol)</td>\n<td>2-3</td>\n</tr>\n<tr>\n<td>2-4</td>\n<td>Parameter Selection Example (2780 Protocol)</td>\n<td>2-4</td>\n</tr>\n<tr>\n<td>2-5</td>\n<td>The Save/Run Menu</td>\n<td>2-15</td>\n</tr>\n<tr>\n<td>2-6</td>\n<td>The Configuration Description Display</td>\n<td>2-15</td>\n</tr>\n<tr>\n<td>2-7</td>\n<td>Sample Configuration Description Display</td>\n<td>2-16</td>\n</tr>\n<tr>\n<td>3-1</td>\n<td>BSC 1 Emulator Loading Sequence Display</td>\n<td>3-1</td>\n</tr>\n<tr>\n<td>3-2</td>\n<td>Sample Operator Screen</td>\n<td>3-4</td>\n</tr>\n<tr>\n<td>3-3</td>\n<td>Operator Screen, General Format</td>\n<td>3-7</td>\n</tr>\n<tr>\n<td>4-1</td>\n<td>HASP Emulator Loading Sequence</td>\n<td>4-1</td>\n</tr>\n<tr>\n<td>4-2</td>\n<td>HASP Emulator Display General Format</td>\n<td>4-2</td>\n</tr>\n<tr>\n<td>4-3</td>\n<td>Sample HASP Emulator Display</td>\n<td>4-3</td>\n</tr>\n<tr>\n<td>4-4</td>\n<td>Console Entry Display</td>\n<td>4-5</td>\n</tr>\n<tr>\n<td>4-5</td>\n<td>Sign-On Display</td>\n<td>4-6</td>\n</tr>\n<tr>\n<td>4-6</td>\n<td>Sample Attention Mode Display</td>\n<td>4-11</td>\n</tr>\n<tr>\n<td>4-7</td>\n<td>HASP Emulator Display for Card Send</td>\n<td>4-12</td>\n</tr>\n<tr>\n<td>G-1</td>\n<td>Vertical Printer Format Display</td>\n<td>G-2</td>\n</tr>\n</tbody>\n</table>\nTABLES\n\nTable 1-1 Communications Controllers for 2200 Series Processors ........ 1-2\nTable 1-2 HASP Emulation Memory Requirements .......................... 1-3\nTable 1-3 2780, 3780, and 3741 Emulation Memory Requirements .......... 1-4\nTable 2-1 HASP Multileaving Parameters and Options ..................... 2-6\nTable 2-2 2780 Parameters and Options .................................. 2-7\nTable 2-3 3780 Parameters and Options .................................. 2-9\nTable 2-4 3741 Parameters and Options .................................. 2-11\nTable 2-5 2200-to-2200 Parameters and Options .......................... 2-13\nTable 2-6 2200 WPS Parameters and Options .............................. 2-13\nTable 3-1 Operational Modes .............................................. 3-3\nTable 3-2 Active Keys for Control, Bid, Send, and Receive Modes ....... 3-5\nTable 3-3 Active Keys for Attention Mode ................................ 3-6\nTable 3-4 Transmission/Reception Status Messages ........................ 3-8\nTable 3-5 Modem Signal Status ............................................. 3-9\nTable 4-1 Key to HASP Emulator Display General Format ................... 4-3\nTable 4-2 Active SF Keys, HASP Control Mode ............................... 4-4\nTable 4-3 Active Keys, Console Entry or Sign-On Entry Mode ............. 4-6\nTable 4-4 Summary of HASP Disk Send Prompts ............................... 4-7\nTable 4-5 HASP Card Send Options ........................................ 4-11\nTable F-1 ASCII Code ...................................................... F-3\nTable F-2 EBCDIC Code ..................................................... F-4\nTable G-1 Vertical Printer Control Line Skips .............................. G-3\nCHAPTER 1\nGENERAL INFORMATION\n\n1.1 SOFTWARE OVERVIEW\n\nThe Wang Binary Synchronous 1 (BSC 1) software provides six binary synchronous communications protocols.\n\n- IBM 2780 protocol\n- IBM 3780 protocol\n- IBM 3741 protocol\n- HASP Multileaving protocol\n- 2200-to-2200 protocol\n- 2200-WPS mode\n\nThe 2780, 3780, and 3741 protocols have become industry standards for data communications equipment designed to handle batched data transmission. These protocols ensure reliable and efficient data communications with computer systems in many service bureaus and major corporations. The HASP Multileaving protocol interleaves multiple batch jobs to accommodate differences in the data handling rates of various input and output devices, thereby improving data throughput capability.\n\nThe Wang 2200-to-2200 protocol combines standard BSC procedures with specialized techniques to facilitate data transfer between two Wang 2200 Series systems. Two 2200VP, SVP, LVP, or MVP systems can use 2200-to-2200 protocol if both systems are equipped with the BSC 1 software (Release 5 or later).\n\nThe 2200 WPS mode is a modified BSC protocol developed to facilitate document transfer between 2200 Series systems and other Wang systems that support word processing. Wang 2200 systems with Word Processing software and the BSC 1 software can communicate with other Wang systems that have synchronous communications capabilities.\n\nThe BSC 1 software is available on a single-sided single-density diskette for 2200VP, LVP, or MVP systems (Package 195-2057-3); or on a double-sided dual-density diskette for 2200SVP systems (Package 195-2057-5).\n\nThe BSC 1 software is designed to accommodate a wide variety of the devices that can communicate using a binary synchronous protocol. The BSC 1 software allows the user to specify the type of communications connection needed for an application, and to save this information (referred to as a configuration) in a disk data file for later use or modification. Since configurations can be created and saved prior to transmission, an operator need\nonly know which configuration is to be used for each communications connection and what data is to be sent using that configuration. The operator loads and runs the correct configuration, supplies the input data or data files to be sent, and chooses the appropriate transmission and reception functions. If necessary, the operator can modify a configuration before establishing a connection (for example, to direct data to a different reception device). The configuration process is accomplished using step-by-step screen prompts, and the configuration is summarized for examination before any communications functions are activated.\n\nThe following configuration functions are contained in the Start and Parameter Selection modules.\n\n- Create a communications configuration. A configuration is a set of parameters (options) chosen to match communications requirements, including the device types and addresses for transmission and reception, the modem type (synchronous or modem eliminator), the connecting line (dial-up or leased), and various protocol-dependent option categories.\n- Save or run any newly specified configuration.\n- Load any previously saved configuration.\n- Delete or modify any previously saved configuration.\n\n1.2 SYSTEM AND PERIPHERAL REQUIREMENTS\n\nThe BSC 1 software operates on Wang systems equipped with a 2200VP, SVP, LVP, or MVP central processor, a Wang Synchronous/Asynchronous Communications Controller, and a suitable modem. Consult Table 1-1 to determine the appropriate communications controller for the 2200 Series processor in use.\n\nTable 1-1. Communications Controllers for 2200 Series Processors\n\n<table>\n<thead>\n<tr>\n<th>Processor</th>\n<th>Communications Controller</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2200MVP, LVP, VP</td>\n<td>Model 2228B or 2228C</td>\n</tr>\n<tr>\n<td>2200SVP</td>\n<td>Option 28B or 28C</td>\n</tr>\n</tbody>\n</table>\n\nUsually, a synchronous modem (not supplied with the controller) is used as an interface between the communications controller and either a leased or dial-up telephone line. For some applications, the Wang 2228N Null Modem and direct cables to a site within the same building may be appropriate. Modem considerations are detailed in Appendix B.\nIf the 2200-to-2200 protocol is to be used to communicate with another 2200 Series processor, each processor must be equipped with Release 5 (or later) of the BSC 1 software, a Wang Synchronous/Asynchronous Communications Controller, and a suitable modem.\n\nIf the 2200 WPS mode is to be used, the 2200 system must have 2200 Word Processing software, BSC 1 software, a Wang Synchronous/Asynchronous Communications Controller, and a synchronous modem. The remote Wang system must have both word processing and synchronous communications capabilities.\n\nThe BSC 1 software supports data transmission from a card reader, disk, or diskette. The software routes received data to a printer, disk, diskette, or minidiskette. These capabilities, however, vary according to the emulation chosen. A printer should be available for on-line printing, or for off-line printing of files received to disk. To transmit data from disk or receive data to disk storage, at least one disk drive must be available. To transmit data solely from a card reader or the keyboard, without disk storage of received data, only one disk drive unit is necessary.\n\n**NOTE**\n\nThe BSC 1 software diskette can be removed from the diskette drive after a BSC 1 configuration is loaded, because all the program modules necessary for operation are loaded into system memory. If only one diskette drive is available, removing the BSC 1 diskette would free a diskette drive for disk transmit and receive functions.\n\nTables 1-2 and 1-3 detail the memory requirements for the BSC 1 software emulations. The tables present the transmission and reception device combinations that can be selected during the configuration process. The 2780, 3780, and 3741 emulations offer two disk access methods: Search and On Error. Generally, a configuration using the On Error disk access method can operate in a partition or processor memory smaller than that required for a configuration using the Search disk access method. Section 2.4 has information on the differences between Search disk operations and On Error disk operations.\n\n**Table 1-2. HASP Emulation Memory Requirements**\n\n<table>\n<thead>\n<tr>\n<th>Transmission Device</th>\n<th>Reception Device</th>\n<th>2200VP or SVP Processor Memory</th>\n<th>2200MVP or LVP Partition Memory</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Card Reader</td>\n<td>Printer</td>\n<td>16K</td>\n<td>15K</td>\n</tr>\n<tr>\n<td>Card Reader</td>\n<td>Printer and Disk</td>\n<td>24K</td>\n<td>21K</td>\n</tr>\n<tr>\n<td>Disk</td>\n<td>Printer</td>\n<td>20K</td>\n<td>16K</td>\n</tr>\n<tr>\n<td>Disk</td>\n<td>Printer and Disk</td>\n<td>24K</td>\n<td>21K</td>\n</tr>\n</tbody>\n</table>\nTable 1-3. 2780, 3780, and 3741 Emulation Memory Requirements\n\n<table>\n<thead>\n<tr>\n<th>Transmission Device</th>\n<th>Reception Device</th>\n<th>Disk Access Method</th>\n<th>2200VP or SVP Processor Memory</th>\n<th>2200MVP or LVP Partition Memory</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Card Reader</td>\n<td>Printer</td>\n<td>None</td>\n<td>16K</td>\n<td>11K</td>\n</tr>\n<tr>\n<td></td>\n<td>Disk</td>\n<td>On Error</td>\n<td>16K</td>\n<td>11K</td>\n</tr>\n<tr>\n<td></td>\n<td>Disk</td>\n<td>Search</td>\n<td>16K</td>\n<td>14K</td>\n</tr>\n<tr>\n<td></td>\n<td>Printer and Disk</td>\n<td>On Error</td>\n<td>16K</td>\n<td>11K</td>\n</tr>\n<tr>\n<td></td>\n<td>Printer and Disk</td>\n<td>Search</td>\n<td>16K</td>\n<td>16K</td>\n</tr>\n<tr>\n<td>Disk</td>\n<td>Printer</td>\n<td>On Error</td>\n<td>16K</td>\n<td>11K</td>\n</tr>\n<tr>\n<td></td>\n<td>Printer</td>\n<td>Search</td>\n<td>16K</td>\n<td>13K</td>\n</tr>\n<tr>\n<td></td>\n<td>Disk</td>\n<td>On Error</td>\n<td>16K</td>\n<td>11K</td>\n</tr>\n<tr>\n<td></td>\n<td>Disk</td>\n<td>Search</td>\n<td>16K</td>\n<td>15K</td>\n</tr>\n<tr>\n<td></td>\n<td>Printer and Disk</td>\n<td>On Error</td>\n<td>16K</td>\n<td>11K</td>\n</tr>\n<tr>\n<td></td>\n<td>Printer and Disk</td>\n<td>Search</td>\n<td>20K</td>\n<td>17K</td>\n</tr>\n</tbody>\n</table>\n\nThe 2200-to-2200 protocol provides transmission from disk and reception to disk, using the Search disk access method. Operation of a 2200-to-2200 protocol configuration requires a processor memory of at least 16K (for 2200VP and SVP) or a partition memory of at least 16K (for 2200MVP and LVP).\n\nThe 2200 WPS mode provides transmission from disk and reception to disk, using the Search disk access method. Operation of a 2200 WPS mode configuration requires a processor memory of at least 16K (for 2200VP and SVP) or a partition memory of at least 14K (for 2200MVP and LVP).\n\n1.3 TC FILE FORMATTING REQUIREMENTS\n\nThe BSC 1 software provides the capability to transmit files from disk and receive files to disk. However, the BSC 1 software is designed to perform disk operations using files that conform to the Wang TC file format. BASIC-2 program files must be converted to TC file format to be transmitted. Data files for use with the 2780, 3780, 3741, and HASP emulators must be created using the TC file format, or converted to TC file format.\n\nThe only exceptions to the requirement for TC-formatted files occur when the 2200-to-2200 protocol and the 2200 WPS mode are used. The 2200-to-2200 protocol is essentially a 2780 protocol that utilizes Transparent mode operations, with modifications to support Wang file formats; program and data files\ncan be sent from one 2200 system to another without reformatting if the 2200-to-2200 protocol is used. The 2200 WPS mode utilizes the TC/WP file format, and the 2200 Word Processing software provides conversion utilities to implement this file format (refer to Section 3.5).\n\nThe conversion of 2200 program files to TC file format and the creation of TC-formatted data files can be accomplished using the Wang TC Support Utilities 1 software. Three of the TC Support Utilities are concerned with the creation and conversion of TC files. These utilities provide a convenient means to create TC-formatted data files or convert program files to TC file format. The three utilities function as follows.\n\n- The DATA ENTRY 1 utility can be used to create a new disk data file in TC file format. DATA ENTRY 1 also provides the capability to edit, delete, rearrange, or list records in an existing TC-formatted file.\n\n- The DE-ATOMIZE utility can be used to convert a BASIC-2 program to a TC-formatted disk data file. The utility copies the program file, and de-atomizes the BASIC-2 commands (converting space-conserving 1-byte text atoms to character-by-character text). This process is necessary because BASIC-2 commands in text atom form would not be transmitted correctly. The DE-ATOMIZE utility then saves the de-atomized program in a TC-formatted file (the original program file remains intact).\n\n- The ATOMIZE utility can be used to convert a BASIC-2 program stored in a TC-formatted file to standard program file format. The utility copies the TC-formatted file, and atomizes the BASIC-2 commands (converting character-by-character data to 1-byte text atoms). This process is necessary because BASIC-2 commands in TC format would not be executed correctly. The ATOMIZE utility then saves the atomized program text in a program file (the original TC-formatted file remains intact).\n\nPrograms to convert user data files to TC-formatted files (and to convert TC-formatted files to user data files) must be written by the user. The TC Support Utilities package contains three subroutines that can be used, for example, as part of a user-programmed file conversion utility to convert existing data files to TC-formatted files. The three subroutines function as follows.\n\n- The OPEN subroutine accepts a file name, performs a file-opening procedure, and returns an indication of the success or failure of the file-opening procedure. OPEN can open an existing TC-formatted file for input (read data from), or create and open a new TC-formatted file for output (write data to).\n\n- The READ subroutine copies a record from a TC-formatted file into a subroutine variable and sets another variable equal to the record's length in bytes (necessary for TC file format operations). READ can be used by a user-written routine to extract records from a TC-formatted file.\nThe WRITE subroutine writes a record to a TC-formatted file. The record must be formatted in TC file format by the user. A user-written routine can be programmed to recover data from user data files, convert that data to TC file format, and use the WRITE subroutine to write that data to a TC-formatted file. If a last-record condition is detected from the user-written subroutine call, the WRITE subroutine writes an End of File (EOF) indicator and closes the TC file.\n\nFor information about these utilities and subroutines, consult the 2200 TC Support Utilities 1 User Manual (700-4086) and addendum. Specifications for the Wang TC file format can be found in Appendix A of the BSC 1 manual and the TC Support Utilities manual.\n\n1.4 SOFTWARE BACKUP\n\nPrepare a backup copy of the software diskette before operating the software for the first time. Label any copies as duplicates, and use the duplicates for all operations. Reserve the master software diskette received from Wang Laboratories for use as backup software, to ensure that an undamaged copy of the software is always available.\n\nTo copy the BSC 1 software onto an empty formatted diskette, use the MOVE statement described in the Wang BASIC-2 Disk Reference Manual (700-4081). The MOVE statement can be used to copy files from one platter to a platter mounted in the same disk unit, or to another disk unit on the same 2200 Series system.\n\nThe Wang Integrated Support System (ISS) contains a COPY/VERIFY utility that can be used in BASIC-2 systems to copy files from one disk platter to another in the same disk unit or in a separate unit. ISS is an optional package that may be ordered for any 2200 Series system.\n\nTo copy the BSC 1 software from diskette to a disk drive, use the BASIC-2 MOVE statement or the ISS COPY/VERIFY utility. However, the BSC 1 software contains a \"START\" program that is used to load the software. Because two programs with identical names cannot be saved on the same disk, the BSC 1 \"START\" program cannot be saved on a disk containing another \"START\" program. Therefore, save the BSC 1 software on a disk without a \"START\" program, if possible. If the BSC 1 software must be saved on a disk containing a \"START\" program, one of the \"START\" programs will have to be renamed. If the BSC 1 \"START\" program is renamed, the program name must be entered during Step 4 of the software loading procedure (refer to Section 1.5). For example, if the program was renamed \"STARTBSC\", Step 4 of the loading procedure would be changed to the following: Press LOAD, then press RUN, then enter \"STARTBSC\".\n\n1-6\n1.5 **LOADING THE BSC 1 SOFTWARE**\n\nTo load the BSC 1 software, mount the BSC 1 diskette in an available diskette drive on the 2200 system and perform the following steps.\n\n1. Press **RESET**.\n2. Enter **SELECT DISK** *xyz* (substitute the device address for *xyz*).\n3. Press **RETURN**.\n4. Press **LOAD**, then press **RUN**.\n5. Press **RETURN**.\n\nThe BSC 1 software main menu then appears.\n\n1.6 **THE BSC 1 MAIN MENU**\n\nWhen the BSC 1 Start module is loaded and execution begins, the CRT is cleared and the BSC 1 main menu appears. This menu initially displays only the option **CREATE A NEW CONFIGURATION**, as shown in Figure 1-1. The standard format of the BSC 1 main menu is presented in Figure 1-2.\n\n```\nWANG 2200 TELECOMMUNICATIONS EMULATORS BSC Rel. 6.00.01\nTO OPERATE -- Press S.F. KEY or DIGIT corresponding to name, or position # via RETURN or BACKSPACE and key RUN, DELETE or RECALL\n\n# '1 CREATE A NEW CONFIGURATION\n```\n\n**Figure 1-1. Initial Format of the BSC 1 Main Menu**\n\nAfter the BSC 1 software has been used to create and save one or more configurations, the BSC 1 main menu displays the available configurations, as shown in Figure 1-2.\n\n```\nWANG 2200 TELECOMMUNICATIONS EMULATORS BSC Rel. 6.00.01\nTO OPERATE -- Press S.F. KEY or DIGIT corresponding to name, or position # via RETURN or BACKSPACE and key RUN, DELETE or RECALL\n\n# '1 CREATE A NEW CONFIGURATION\n'2 Load (first user-defined configuration)\n'3 Load (second user-defined configuration)\n.\n.\n'n Load (last user-defined configuration)\n```\n\n**Figure 1-2. General Format of the BSC 1 Main Menu**\nThe first line of the BSC 1 main menu identifies the software and shows the release number. The release number indicates the current version of the BSC 1 software. The release number (given in the format x.y.z) denotes major and minor changes in the software. The \"x\" identifies the release number; the \"y\" and the \"z\" identify particular revisions. Revisions often represent changes transparent to a user, and require no changes in the documentation.\n\nEach available configuration is identified by a number representing a Special Function (SF) key, the word \"Load,\" and a description. The configuration description is supplied by the user when the configuration is originally created and saved. A sample of a BSC 1 main menu with several user-defined configuration descriptions is presented in Figure 1-3.\n\n```\nWANG 2200 TELECOMMUNICATIONS EMULATORS BSC Rel. 6.00.01\nTO OPERATE -- Press S.F. KEY or DIGIT corresponding to name, or position # via RETURN or BACKSPACE and key RUN, DELETE or RECALL\n\n# '1 CREATE A NEW CONFIGURATION\n'2 Load 2780 leased-line, to disk in ASCII\n'3 Load HASP #2 (data-transfer to main office)\n'4 Load 3741 for card send to Akron office\n'5 Load Fran's test emulator\n```\n\nFigure 1-3. Sample BSC 1 Main Menu\n\nA configuration description might describe the emulation connection, as the description adjacent to '2 does in Figure 1-3. A combination of a descriptive name, the connection protocol, and the primary remote site name or location (as in Descriptions '3 and '4 in Figure 1-3) is a useful convention for naming configurations. The configuration name itself need not be unique, because each configuration name is associated with a unique SF key in the BSC 1 main menu. The process of naming and saving configurations is detailed in Section 2.5.\n\n```\nNOTE\n\nSF'0 is active from the BSC 1 main menu, the Emulator Selection menu, and during the configuration process. Pressing SF'0 aborts the current operation and invokes the BSC 1 main menu.\n```\nCHAPTER 2\nCREATING A COMMUNICATIONS CONFIGURATION\n\n2.1 CREATING A NEW CONFIGURATION\n\nTo generate a new configuration that implements a particular BSC protocol and matches the characteristics used by a terminal or host computer, begin by mounting the BSC 1 software diskette. Next, load the software using the steps outlined in Section 1.5. After the BSC 1 main menu appears, press SF'1 to activate CREATE A NEW CONFIGURATION. The screen clears and the Emulator Selection menu appears.\n\n2.2 SELECTING AN EMULATION\n\nThe Emulator Selection menu for the BSC 1 software lists all the available protocols, as shown in Figure 2-1.\n\n<table>\n<thead>\n<tr>\n<th>#</th>\n<th>Emulation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>Multileaving Hasp</td>\n</tr>\n<tr>\n<td>2</td>\n<td>IBM 2780</td>\n</tr>\n<tr>\n<td>3</td>\n<td>IBM 3780</td>\n</tr>\n<tr>\n<td>4</td>\n<td>IBM 3741</td>\n</tr>\n<tr>\n<td>5</td>\n<td>Wang 2200 to 2200</td>\n</tr>\n<tr>\n<td>6</td>\n<td>2200-WPS Mode</td>\n</tr>\n</tbody>\n</table>\n\nWHAT EMULATION?\nTO OPERATE -- Press S.F. KEY or DIGIT corresponding to name, or position # via RETURN, SPACE or BACKSPACE and key RUN\n\nFigure 2-1. The Emulator Selection Menu\n\nEach protocol contained in the BSC 1 software is assigned an SF key number. To select the desired protocol, press the SF key that is listed in the Emulator Selection menu to the left of the protocol. There are two alternative methods for choosing an emulation: the digit key method and the flag (\"#\") method.\n\nTo use the digit key method, press the digit key whose number is the same as the SF key number assigned to the desired emulation.\nTo use the flag (\"#\") method, perform the following steps.\n\n1. Use RETURN, BACKSPACE, or the Space Bar to position the \"#\" next to the desired emulation.\n\n2. Press RUN.\n\nAfter an emulator is selected, the screen clears and a Parameter Selection menu appears.\n\n2.3 SPECIFYING VALID PARAMETERS FOR A NEW CONFIGURATION\n\nA Wang 2200VP, SVP, LVP, or MVP system equipped with the BSC 1 software and a Wang Synchronous/Asynchronous Communications Controller can communicate with either another Wang system or a non-Wang system with appropriate synchronous communications capabilities. The systems can be remotely connected using leased or switched telephone lines and a pair of synchronous modems. Local connection using EIA (Electronic Industries Association) RS-232-C/CCITT (Consultative Committee for International Telegraph and Telephone) V.24-compatible cables and the Wang 2228N Null Modem is also possible (refer to Appendix B).\n\nBecause the means of implementing data communications between systems differ, the BSC 1 software can accommodate a reasonable variety of the equipment and communications line combinations that are possible. Parameter values can be specified to suit the modem, line speed, and the line type (dial-up or leased), since some differences in the BSC emulator are necessary to support these options. The software can also accommodate the preferred record blocking method (single record or multi-record); the disk access method (if a disk or diskette drive is the device chosen for data transmission or reception); the terminal ID for 2780, 3780, and 3741 emulation; and the desired output code for data received in transparent mode from the remote site.\n\nThe BSC 1 software contains Parameter Selection menus specific to each of the available protocols. These menus present the valid parameter options for each protocol (in a multiple-choice format), along with a set of default selections. These menus guide the user through the customizing procedure associated with creating a configuration for communications with one or more remote sites.\n\nThe parameters to be selected vary in number and type, depending upon which protocol is chosen by the operator prior to the appearance of a Parameter Selection menu. For several protocols, the Parameter Selection menu appears in two parts. Figures 2-2 and 2-3 show Parts 1 and 2 of the Parameter Selection menu for the 2780 protocol. Even though a reader may wish to create a communications configuration for a protocol other than 2780, the menus in Figures 2-2 and 2-3 should be studied carefully. The parameter selection procedure is fundamentally the same for all BSC 1 protocols; only the specific parameters vary.\n\nThe screen display shown in Figure 2-2 appears after an emulator is selected from the Emulator Selection menu.\nFigure 2-2. Parameter Selection Menu, Part 1 (2780 Protocol)\n\nThe top line in Figure 2-2 indicates the protocol for the parameters being selected. The Parameter Selection menus for 2780, 3780, and 3741 emulations have two parts; the second part is used to specify the devices for transmission and reception, as illustrated in Figure 2-3. The format of the menu and the selection process do not differ from Part 1 to Part 2; only the names of the parameters and the valid options are different.\n\nFigure 2-3. Parameter Selection Menu, Part 2 (2780 Protocol)\nThere are four information categories in the Parameter Selection menu. PARAMETER contains a set of parameter options that need to be specified for the protocol. OPTIONS FOR lists a parameter and the choices available for that parameter. CURRENT SELECTION contains the option currently chosen for each parameter. Initially, a default selection is displayed under CURRENT SELECTION. ACTIVE KEYS lists the keys that can be used for parameter selection.\n\nUnder PARAMETER, a \"#\" appears to the left of the parameter list. The \"#\" serves as a flag; it allows a value to be selected for a parameter. When the \"#\" is moved to another position within the parameter list (by use of RETURN, BACKSPACE, or the Space Bar), the parameter name flagged by the \"#\" and the available options for this parameter appear under OPTIONS FOR.\n\nEach item under OPTIONS FOR is represented by a number and a brief description. To change the current selection for the flagged parameter, press the digit key corresponding to the desired option. The new selection then replaces the previous selection under CURRENT SELECTION. In Figure 2-2, the flagged parameter is MODEM TYPE; therefore, the OPTIONS FOR selections correspond to this parameter. If 2 is pressed, the current selection for MODEM TYPE changes to \"2400 BPS (null modem)\". If the \"#\" is moved to a different parameter, that parameter name appears adjacent to OPTIONS FOR, and a different set of options appears under OPTIONS FOR. After an option is chosen, the \"#\" automatically cycles to the next PARAMETER category.\n\nFor example, if a 2780 emulation configuration is needed for communications via a null modem at a line speed of 4800 bps, Option 3 should be chosen for MODEM TYPE. After Option 3 is chosen, the Parameter Selection menu would appear as in Figure 2-4. Note that the options under OPTIONS FOR have changed to reflect the flagged parameter MODEM OPERATES.\n\n<table>\n<thead>\n<tr>\n<th>2780 Parameters</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>PARAMETER</strong></td>\n</tr>\n<tr>\n<td>MODEM TYPE</td>\n</tr>\n<tr>\n<td># MODEM OPERATES</td>\n</tr>\n<tr>\n<td>RECORD BLOCKING</td>\n</tr>\n<tr>\n<td>RECEIVE TRANSPARENCY?</td>\n</tr>\n<tr>\n<td>MULTIPOINT?</td>\n</tr>\n<tr>\n<td>LINE CODE</td>\n</tr>\n</tbody>\n</table>\n\nOPTIONS FOR -- MODEM OPERATES\n1 Dial-up line\n2 Leased line\n\nACTIVE KEYS --\n--DIGITS--\n--RETURN--\n--BACKSPACE--\n--RECALL--\n\nFigure 2-4. Parameter Selection Example (2780 Protocol)\nACTIVE KEYS lists the keys that are active during parameter selection. The RUN key is active only while the first parameter is flagged. When a different parameter is flagged, the RUN key is deleted from the ACTIVE KEYS list. (Note that while RUN is displayed as an active key in Figures 2-2 and 2-3, RUN is no longer displayed as an active key in Figure 2-4, because the \"#\" is no longer adjacent to the first parameter.)\n\nUntil RUN is pressed when active, the software retains the user's responses. The responses can be changed during parameter selection any number of times before RUN is pressed. After RUN is pressed, the software stores the responses as part of the modified or newly created configuration and proceeds to the next step in the configuration process. The active keys are used as follows.\n\n- **DIGITS** -- Press a DIGIT key to change the selected option for the flagged parameter. The description corresponding to the keyed digit then appears in the CURRENT SELECTIONS category.\n\n- **RETURN** -- Press RETURN to move the \"#\" down in the PARAMETER category. (With successive keystrokes, the flag reaches the last parameter and cycles to the top before moving downward again.)\n\n- **BACKSPACE** -- Press BACKSPACE to move the \"#\" upward in the list.\n\n- **RECALL** -- Press RECALL (SF'15) to reset each parameter selection to its initial setting (the setting before modification was attempted, not the emulator default setting). This procedure may be especially useful during the recall/modify procedure described in Section 2.7.\n\n- **RUN** -- Press RUN to indicate acceptance of the currently displayed selections and activate either the next part of the Parameter Selection menu (if there is another part) or the Save/Run menu (refer to Section 2.5).\n\nTables 2-1 through 2-6 present the complete set of parameters for the BSC 1 software emulations. Note that not all of the parameters listed for an emulator necessarily appear on the screen during the parameter selection process. Some of the parameter options appear only as a result of a user response to another parameter. For example, when the user is creating a configuration for 2780 emulation, the parameter for Disk Access Method does not appear unless a parameter option enabling disk send or receive operations is chosen.\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Options</th>\n<th>Remarks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Input Device</td>\n<td>1 Disk</td>\n<td>Choose the source device from which data will be transmitted.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 Card Reader</td>\n<td></td>\n</tr>\n<tr>\n<td>Transparent</td>\n<td>1 Translate to EBCDIC before send</td>\n<td>Choose Option 1 to translate data to EBCDIC code prior to transmission.</td>\n</tr>\n<tr>\n<td>Send?</td>\n<td>2 Send w/o translation</td>\n<td>Choose Option 2 to send data without translation.</td>\n</tr>\n<tr>\n<td>Print Streams</td>\n<td>1 Printer</td>\n<td>Option 1 routes received data streams to the printer; Option 2 routes print</td>\n</tr>\n<tr>\n<td>To*</td>\n<td>2 Disk (spooled)</td>\n<td>streams to disk in TC file format (refer to Appendix A). Spooled print</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>files contain a vertical format control byte preceding the text data;</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>these files may be printed off-line using the Wang TC Support utilities.</td>\n</tr>\n<tr>\n<td>Punch Streams</td>\n<td>1 None</td>\n<td>With Option 1, punch data streams are inactive. Option 2 translates punch</td>\n</tr>\n<tr>\n<td>To**</td>\n<td>2 Disk in ASCII</td>\n<td>streams to ASCII prior to storage on disk in TC-formatted files. Option 3</td>\n</tr>\n<tr>\n<td></td>\n<td>3 Disk w/o Translation</td>\n<td>selects disk storage without translation from EBCDIC to ASCII.</td>\n</tr>\n<tr>\n<td>TC Board Address</td>\n<td>1 1C</td>\n<td>Select the device address of the 2200 TC controller being used.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 1D</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 1E</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>4 1F</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n* If emulator partition size must be 16K or less, select Option 1 for the Print Streams To parameter and Option 1 for the Punch Streams To parameter. (Do not select parameters activating disk send or receive operations.)\n\n** Parameter appears only if the selection for Print Streams To is Option 1 (Printer).\n<table>\n<thead>\n<tr>\n<th>Parameter*</th>\n<th>Options</th>\n<th>Remarks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Modem Type</td>\n<td>1 Synchronous 2000-4800 2 2400 BPS (null modem) 3 4800 BPS (null modem) 4 Synchronous (Drop DIR)</td>\n<td>For communications via a synchronous modem, select Option 1 or 4. With Option 4, the emulator drops Data Terminal Ready after 3 minutes of line inactivity. Select Option 2 or 3 for connection via a null modem (the Wang communications controller provides the clocking signal).</td>\n</tr>\n<tr>\n<td>Modem Operates</td>\n<td>1 Dial-up line 2 Leased line</td>\n<td>Select Option 1 for use with a dial-up line; otherwise, select Option 2.</td>\n</tr>\n<tr>\n<td>Record Blocking</td>\n<td>1 Multi-record 2 Single record</td>\n<td>The 2200 record blocking option must match the record blocking option at the remote site; otherwise, the sent or received blocks may be rejected.</td>\n</tr>\n<tr>\n<td>Receive Transparency</td>\n<td>1 To disk in ASCII 2 To disk without translation</td>\n<td>Select Option 1 to route transparent data to disk in ASCII; select Option 2 for disk storage in EBCDIC code. Transparent data routed to a printer is printed in hexadecimal code.</td>\n</tr>\n<tr>\n<td>Multipoint</td>\n<td>1 No 2 Yes</td>\n<td>Select Option 1 for point-to-point emulator operations, or Option 2 for multipoint emulator operations.</td>\n</tr>\n<tr>\n<td>Terminal ID</td>\n<td>(Supply ID)</td>\n<td>Supply a 1-letter Terminal ID (A-Z or a-z). This parameter appears if Option 2 is chosen for the Multipoint parameter.</td>\n</tr>\n<tr>\n<td>Line Code**</td>\n<td>1 EBCDIC 2 ASCII</td>\n<td>Select Option 1 to translate data to EBCDIC before transmission, or Option 2 to transmit data in ASCII (without translation).</td>\n</tr>\n</tbody>\n</table>\n\n* Parameters appear in a 2-part menu; Part 2 begins with the Send From parameter.\n\n** This parameter appears only if Option 1 is chosen for the Multipoint parameter.\n<table>\n<thead>\n<tr>\n<th>Parameter*</th>\n<th>Options</th>\n<th>Remarks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Send From</td>\n<td>1 Disk</td>\n<td>Choose the source device from which data will be transmitted.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 Card Reader</td>\n<td></td>\n</tr>\n<tr>\n<td>Receive To</td>\n<td>1 All streams to printer</td>\n<td>2780 data streams are either print or punch streams. Option 1 routes all received streams to the printer. Option 2 routes received print streams to the printer and stores received punch streams on disk in TC file format (refer to Appendix A). Option 3 routes all received streams to disk for storage in TC-formatted files. TC format files saved on disk can be printed off-line using the Wang TC Support utilities.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 Printer and disk</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 All streams to disk</td>\n<td></td>\n</tr>\n<tr>\n<td>Disk Access Method**</td>\n<td>1 via Search</td>\n<td>Choose Option 1 unless the emulator must run in a partition smaller than 16K. Refer to Section 2.4 for more information.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 via On Error</td>\n<td></td>\n</tr>\n<tr>\n<td>Save Print Files</td>\n<td>1 with line control</td>\n<td>Option 1 includes line control codes in print files routed to disk. Option 2 routes print files to disk without including line control codes (this parameter appears only if Option 3 is chosen for the Receive To parameter).</td>\n</tr>\n<tr>\n<td></td>\n<td>2 without line control</td>\n<td></td>\n</tr>\n<tr>\n<td>TC Board Address</td>\n<td>1 1C</td>\n<td>Select the device address of the 2200 TC controller being used.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 1D</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 1E</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>4 1F</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n* Parameters appear in a 2-part menu; Part 2 begins with the Send From parameter.\n\n** This parameter appears only if the Send From selection is Option 1 (Disk), or the Receive To selection is Option 2 (Printer and disk) or Option 3 (All streams to disk).\nTable 2-3. 3780 Parameters and Options\n\n<table>\n<thead>\n<tr>\n<th>Parameter*</th>\n<th>Options</th>\n<th>Remarks</th>\n</tr>\n</thead>\n</table>\n| Modem Type | 1 Synchronous 2000-4800 \n 2 2400 BPS (null modem) \n 3 4800 BPS (null modem) \n 4 Synchronous (Drop DTR) | For communications via a synchronous modem, select Option 1 or 4. With Option 4, the emulator drops Data Terminal Ready after 3 minutes of line inactivity. Select Option 2 or 3 for connection via a null modem (the Wang communications controller provides the clocking signal). |\n| Modem Operates | 1 Dial-up line \n 2 Leased line | Select Option 1 for use with a dial-up line; otherwise, select Option 2. |\n| Record Blocking | 1 Multi-record \n 2 Single record | The 2200 record blocking option must match the record blocking option at the remote site; otherwise, sent or received blocks may be rejected. |\n| Receive Transparency | 1 To disk in ASCII \n 2 To disk without translation | Select Option 1 to route transparent data to disk in ASCII; select Option 2 for disk storage in EBCDIC code. Transparent data routed to a printer is printed in hexadecimal code. |\n| Received Data | 1 Space Compressed \n 2 Horizontal Tabs | Select Option 1 if the host system supports 3780 space compression. Select Option 2 to use horizontal tabbing for space compression. |\n| Transmitted Data** | 1 Compressed \n 2 As Is | Select Option 1 for space compression of transmitted data. Option 2 permits transmission of repetitious blanks. |\n| Multipoint | 1 No \n 2 Yes | Select Option 1 for point-to-point emulator operations, or Option 2 for multipoint emulator operations. |\n| Terminal ID | (Supply ID) | Supply a 1-letter Terminal ID (A-Z). This parameter appears only if Option 2 is chosen for the Multipoint parameter. |\n\n* Parameters appear in a 2-part menu; Part 2 begins with the Send From parameter.\n\n** This parameter appears only if the Received Data selection is Option 1 (Space Compressed).\nTable 2-3. 3780 Parameters and Options (continued)\n\n<table>\n<thead>\n<tr>\n<th>Parameter*</th>\n<th>Options</th>\n<th>Remarks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Send From</td>\n<td>1 Disk</td>\n<td>Choose the source device from which data will be transmitted.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 Card Reader</td>\n<td></td>\n</tr>\n<tr>\n<td>Receive To</td>\n<td>1 All streams to printer</td>\n<td>Unlike 2780 protocol data streams, 3780 data streams are only print</td>\n</tr>\n<tr>\n<td></td>\n<td>2 Printer and disk</td>\n<td>streams. Data streams can be routed to the printer with Option 1 or to</td>\n</tr>\n<tr>\n<td></td>\n<td>3 All streams to disk</td>\n<td>disk with Option 3. Option 2 routes the streams to printer and to disk.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>TC format files saved on disk can be printed off-line using the Wang TC</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Support utilities.</td>\n</tr>\n<tr>\n<td>Disk</td>\n<td>1 via Search</td>\n<td>Option 1 is recommended unless the emulator must run in a partition</td>\n</tr>\n<tr>\n<td>Access</td>\n<td>2 via On Error</td>\n<td>smaller than 16K. Refer to Section 2.4 for more information.</td>\n</tr>\n<tr>\n<td>Method**</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Save</td>\n<td>1 with line control</td>\n<td>Option 1 includes line control codes in print files routed to disk. Op-</td>\n</tr>\n<tr>\n<td>Print</td>\n<td>2 without line control</td>\n<td>tion 2 routes print files to disk without including line control codes</td>\n</tr>\n<tr>\n<td>Files</td>\n<td></td>\n<td>(this parameter appears only if Option 3 is chosen for the Receive To</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>parameter).</td>\n</tr>\n<tr>\n<td>TC Board</td>\n<td>1 1C</td>\n<td>Select the device address of the 2200 TC controller being used.</td>\n</tr>\n<tr>\n<td>Address</td>\n<td>2 1D</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 1E</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>4 1F</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n* Parameters appear in a 2-part menu; Part 2 begins with the Send From parameter.\n\n** This parameter appears only if the Send From selection is Option 1 (Disk), or the Receive To selection is Option 2 (Printer and disk) or Option 3 (All streams to disk).\n<table>\n<thead>\n<tr>\n<th>Parameter*</th>\n<th>Options</th>\n<th>Remarks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Modem Type</td>\n<td>1 Synchronous 2000-4800 2 2400 BPS (null modem) 3 4800 BPS (null modem) 4 Synchronous (Drop DTR)</td>\n<td>For communications via a synchronous modem, select Option 1 or 4. With Option 4, the emulator drops Data Terminal Ready after 3 minutes of line inactivity. Select Option 2 or 3 for connection via a null modem (the Wang communications controller provides the clocking signal).</td>\n</tr>\n<tr>\n<td>Modem Operates</td>\n<td>1 Dial-up line 2 Leased line</td>\n<td>Select Option 1 for use with a dial-up line; otherwise, select Option 2.</td>\n</tr>\n<tr>\n<td>Record Blocking</td>\n<td>1 Multi-record 2 Single record</td>\n<td>The 2200 record blocking option must match the record blocking option at the remote site; otherwise, sent or received blocks may be rejected.</td>\n</tr>\n<tr>\n<td>Terminal ID</td>\n<td>1 No 2 Yes</td>\n<td>3741 protocol optionally supports an imbedded Terminal ID code (1 to 4 characters) at the start of a message. Select Option 2 to activate the Terminal ID feature; otherwise, select Option 1.</td>\n</tr>\n<tr>\n<td>1 to 4 Character ID**</td>\n<td>Supply the ID (1 to 4 alphanumeric characters)</td>\n<td>Do not use this ID as an address on a multipoint line.</td>\n</tr>\n</tbody>\n</table>\n\n* Parameters appear in a 2-part menu; Part 2 begins with the Send From parameter.\n\n** This parameter appears only if the Terminal ID selection is Option 1 (Yes).\n<table>\n<thead>\n<tr>\n<th>Parameter*</th>\n<th>Options</th>\n<th>Remarks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Send From</strong></td>\n<td></td>\n<td><strong>Remarks</strong></td>\n</tr>\n<tr>\n<td></td>\n<td>1 Disk</td>\n<td>Choose the source device from which data will be transmitted.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 Card Reader</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>Receive To</strong></td>\n<td>1 All streams to printer</td>\n<td>3741 data streams are either print or punch streams. Option 1 routes all received streams to the printer. Option 2 routes received print streams to the printer and stores received punch streams on disk in TC file format (refer to Appendix A). Option 3 routes all received streams to disk for storage in TC-formatted files. TC format files saved on disk can be printed off-line using the Wang TC Support utilities.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 Printer and disk</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 All streams to disk</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>Disk Access Method</strong></td>\n<td>1 via Search</td>\n<td>Choose Option 1 unless the emulator must run in a partition smaller than 16K. Refer to Section 2.4 for more information.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 via On Error</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>Save Print Files</strong></td>\n<td>1 with line control</td>\n<td>Option 1 includes line control codes in print files routed to disk. Option 2 routes print files to disk without including line control codes (this parameter appears only if Option 3 is chosen for the Receive To parameter).</td>\n</tr>\n<tr>\n<td></td>\n<td>2 without line control</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>TC Board Address</strong></td>\n<td>1 1C</td>\n<td>Select the device address of the 2200 TC controller being used.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 1D</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 1E</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>4 1F</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n* Parameters appear in a 2-part menu; Part 2 begins with the **Send From** parameter.\n\n** This parameter appears only if the **Send From** selection is Option 1 (Disk), or the **Receive To** selection is Option 2 (Printer and disk) or Option 3 (All streams to disk).\n### Table 2-5. 2200-to-2200 Parameters and Options\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Options</th>\n<th>Remarks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Modem Type</td>\n<td>1 Synchronous 2000-4800</td>\n<td>For communications via a synchronous modem, select Option 1 or 4. With Option 4, the emulator drops Data Terminal Ready after 3 minutes of line inactivity. Select Option 2 or 3 for connection via a null modem (the Wang communications controller provides the clocking signal).</td>\n</tr>\n<tr>\n<td></td>\n<td>2 2400 BPS (null modem)</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 4800 BPS (null modem)</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>4 Synchronous (Drop DTR)</td>\n<td></td>\n</tr>\n<tr>\n<td>Modem Operates</td>\n<td>1 Dial-up line</td>\n<td>Select Option 1 for use with a dial-up line; otherwise, select Option 2.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 Leased line</td>\n<td></td>\n</tr>\n<tr>\n<td>TC Board Address</td>\n<td>1 1C</td>\n<td>Select the device address of the 2200 TC controller being used.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 1D</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 1E</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>4 1F</td>\n<td></td>\n</tr>\n<tr>\n<td>Remote 2200 Uses</td>\n<td>1 28B or C (Release 6)</td>\n<td>Select the controller type used by the remote 2200. Options 1 and 2 select 2228B, 2228C, Option 28B or Option 28C. Option 2 selects 2228D or Option 28D. Choose Option 2 if the remote 2200 uses BSC 1 Release 5 software.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 28B or C (Release 5)</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 28D</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n### Table 2-6. 2200 WPS Parameters and Options\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Options</th>\n<th>Remarks</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Modem Type</td>\n<td>1 Synchronous 2000-4800</td>\n<td>For communications via a synchronous modem, select Option 1 or 4. With Option 4, the emulator drops Data Terminal Ready after 3 minutes of line inactivity. Select Option 2 or 3 for connection via a null modem (the Wang communications controller provides the clocking signal).</td>\n</tr>\n<tr>\n<td></td>\n<td>2 2400 BPS (null modem)</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 4800 BPS (null modem)</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>4 Synchronous (Drop DTR)</td>\n<td></td>\n</tr>\n<tr>\n<td>Modem Operates</td>\n<td>1 Dial-up line</td>\n<td>Select Option 1 for use with a dial-up line; otherwise, select Option 2.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 Leased line</td>\n<td></td>\n</tr>\n<tr>\n<td>TC Board Address</td>\n<td>1 1C</td>\n<td>Select the device address of the 2200 TC controller being used.</td>\n</tr>\n<tr>\n<td></td>\n<td>2 1D</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>3 1E</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>4 1F</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n2.4 DISK ACCESS METHODS\n\nThere are two disk access methods for the 2780, 3780, and 3741 emulations: Search and On Error. Either option can be chosen during the configuration process. The methods differ in the amount of memory required for operation and in the way that they access a disk for sending and receiving files.\n\nThe Search method enables the software to search the disk catalog to validate user-supplied file names. If an invalid or nonexistent file name is entered during a file send operation, a software prompt indicates that the file is not cataloged or that the given file name is invalid. The software then requests a new send file name. If an invalid or existing file name is entered during the process of creating and opening a receive file, a software prompt indicates that the file exists (as the disk will not accommodate duplicate file names) or that the file name given is invalid. The software then requests a new receive file name. Also, when receiving files using the Search method, the system temporarily allocates all the remaining platter space; unused space is freed when a file is closed.\n\nIf the On Error method is used, a configuration will run in a smaller partition than a configuration using the Search method (refer to Section 1.2 and Table 1-3); however, with the On Error method, disk handling capabilities are more limited. When the On Error method is used, the software does not validate send or receive file names. The software captures and flags erroneous file name entries via the ON ERROR statement during file send or receive operation. If a nonexistent file name is entered during a file send operation, or an invalid file name is entered during a receive operation, the operation terminates with a STOP statement, signaling that a disk access error occurred. If this happens, the emulator has to be reactivated and the interrupted operations may have to be performed again. Also, when receiving files, the system allocates equal space to each file (the number of sectors is operator-specified in response to a screen prompt; unused space is not freed). The software does not automatically open consecutive receive files if a received file overflows the allotted file space.\n\nFor more information about the Search and On Error disk access methods, refer to Sections 3.6 and 3.7.\n\n2.5 SAVING A NEW CONFIGURATION\n\nThe BSC 1 software provides the capability to save up to 14 configurations in a file on the BSC 1 software diskette. To begin the process of saving a new configuration, press RUN to accept the currently displayed selections in a Parameter Selection menu. A second Parameter Selection menu appears if the emulation chosen uses two menus for configuration; otherwise, the Save/Run menu appears (refer to Figure 2-5).\nSAVE IT OR RUN? — Key SF '0' to exit\nTO OPERATE — Press S.F. KEY or DIGIT corresponding to option,\nor position # via RETURN, SPACE or BACKSPACE and key RUN.\n\n1 FOR RUN CREATED VERSION\n2 FOR SAVE CREATED VERSION\n\nFigure 2-5. The Save/Run Menu\n\nSF'0' can be used to abort the CREATE A CONFIGURATION activity from the\nSave/Run menu. If SF'0' is pressed, the newly created configuration is not\nsaved, and the BSC 1 main menu is displayed.\n\nTo run a newly created configuration immediately, but only once, from\nthe Save/Run menu, press SF'1' or Digit Key 1. The configuration is run, but\nit is not stored on the BSC 1 software disk and cannot be retrieved for later\nuse. To save a newly created configuration for subsequent use, press either\nSF'2' or Digit Key 2 from the Save/Run menu. The configuration can be deleted\nor modified later if, during testing or operation, the configuration does not\nappear to be suitable for its intended application.\n\nAfter SF'2' or Digit Key 2 is pressed, the Configuration Description\ndisplay appears as shown in Figure 2-6.\n\nSAVE THE PARAMETERS YOU HAVE GENERATED\n\nEXISTING CALLS--\n'2 FOR (first user-defined configuration)\n'3 FOR (second user-defined configuration)\n.\n'n FOR (last user-defined configuration)\n\nTHESE PARAMETERS--\nEmulator type --- (system-supplied emulator name)\nInput capability --- (system-supplied transmission module description)\nOutput capability --- (system-supplied reception module description)\n\nKEY 1-40 BYTE....!....1....!....2....!....3....!....4\nDESCRIPTION?\n\nFigure 2-6. The Configuration Description Display\nThere are two information categories in the Configuration Description display. EXISTING CALLS shows the user-supplied descriptions for any previously configured emulator stored on the platter. THESE PARAMETERS shows the following parameters for the newly configured emulator: emulator type, transmission capability, and reception capability. The last two lines of the display allow a configuration description to be entered for the new configuration.\n\nIn Figure 2-6, note that the configuration description may be 1 to 40 characters in length. As a description is entered, each character is displayed beneath the 40-byte scale. This scale has 10-byte divisions marked by the digits 1 through 4; the 5-byte subdivisions are marked by exclamation points. Figure 2-7 presents a sample Configuration Description display.\n\nSAVE THE PARAMETERS YOU HAVE GENERATED\n\nEXISTING CALLS—\n' 2 FOR 2780 leased-line, to disk in ASCII\n' 3 FOR HASP #2 (data-transfer to main office)\n' 4 FOR 3741 for card send to Akron office\n' 5 FOR Kelly's test emulator\n\nTHESE PARAMETERS—\nEmulator type --- 2200-to-2200\nInput capability --- disk-send\nOutput capability --- disk-receive\n\nKEY 1-40 BYTE...1....2....3....4\nDESCRIPTION? 2200-to-2200 disk send/receive\n\nFigure 2-7. Sample Configuration Description Display\n\nAlthough unique descriptions are advisable if several communications configurations are saved, duplicate descriptions are acceptable because a unique SF key is automatically assigned to each configuration. After entering a description for the new configuration, press RETURN. The new configuration is then saved on the BSC 1 software platter, and the BSC 1 main menu reappears. The user-supplied description and the SF key number for the saved configuration are added automatically to the BSC 1 main menu.\n\nThe new configuration can now be loaded into memory using the instructions displayed with the BSC 1 main menu. These instructions are discussed further in the next section.\n\n2.6 LOADING A CONFIGURATION\n\nA saved communications configuration is loaded from the BSC 1 main menu. If the configuration has just been saved by entry of a configuration description, the BSC 1 main menu appears automatically after the operator presses RETURN to save the configuration. The configuration can then be loaded. If a configuration has been saved previously, it can be loaded from the BSC 1 main menu after the BSC 1 software is loaded.\nIf the \"#\" is in its default position (i.e., next to CREATE A NEW CONFIGURATION) when the BSC 1 main menu appears, there are two ways to load a communications configuration with a single keystroke.\n\n- Press the SF key whose number corresponds to the number of the desired user-described configuration.\n\n- Press the digit key that matches the SF key number of the configuration. (Note that this method can only be used to load configurations numbered 2-9, because only single-digit entries are accepted. This means, for example, that trying to press 1 and 3 to load configuration '13 would instead select CREATE A NEW CONFIGURATION.)\n\nA third way to load a configuration requires more than one keystroke. Press RETURN or the Space Bar to move the \"#\" down (or BACKSPACE to move the \"#\" up) in the BSC 1 main menu until the \"#\" is next to the desired configuration; then press RUN.\n\n2.7 DELETING OR MODIFYING A CONFIGURATION\n\nThe BSC 1 software provides a means for deleting or modifying previously saved configurations. To delete a configuration that is no longer needed, perform the following steps from the BSC 1 main menu.\n\n1. Position the \"#\" next to the configuration description to be deleted (using the RETURN, BACKSPACE, or Space Bar keys).\n\n2. Press DELETE (SF'9).\n\n**CAUTION**\n\nSF'9 can be used to load Configuration '9 only if the \"#\" is next to '1 CREATE A NEW CONFIGURATION. If the \"#\" has been moved from the position next to '1 to a position next to another configuration description, an attempt to use SF'9 to load Configuration '9 instead activates the DELETE function. The configuration adjacent to the \"#\" is then deleted.\n\nThe configuration is deleted from the BSC 1 software platter, and the configuration description is removed from the BSC 1 main menu.\n\n**NOTE**\n\nTo delete all configurations from the BSC 1 main menu, press the RESET key, then press SF'31, RUN, and RETURN. The BSC 1 main menu then appears on the screen without any user-specified configurations, as in Figure 1-1.\nThe modification process retrieves a previously saved configuration for modification. The modified configuration can then be run or saved. The previously saved configuration remains intact; it can be deleted when the modified configuration is tested and verified, or it can be retained on the BSC 1 platter if needed.\n\nTo modify a configuration (i.e., to change any of the currently selected parameters or the configuration description for a particular emulation program), perform the following steps from the BSC 1 main menu.\n\n1. Press RECALL (SF'15).\n\n2. Choose one of the following.\n a. Position the \"#\" next to the description of the configuration to be modified, and press RUN.\n b. Press the digit or SF key whose number matches the SF key number for the description of the configuration to be modified.\n\n4. When the Parameter Selection menu for the described configuration appears, change one or more current selections, if desired.\n\n5. When the current selections are satisfactory, move the \"#\" adjacent to the first parameter (so that RUN is an active key) and press RUN.\n\n6. If another part of the Parameter Selection menu appears, repeat Steps 4 and 5.\n\n7. When the Save/Run menu appears, save or run the modified configuration using the procedure described in Section 2.5. (Remember that if the configuration is run from this menu, it is not saved, and must be generated again to be run again.)\n\nIf the modified configuration is saved, a unique SF key is assigned to the modified configuration, and this configuration is added to the BSC 1 main menu. The original configuration is still available for use, or it may be deleted.\n\n--- NOTE ---\n\nBecause SF'15 is active from the BSC 1 main menu to enable the RECALL feature, this SF key cannot be used to activate a configuration. If enough configurations are saved so that a configuration is assigned SF'15, there is only one way to activate that configuration: use RETURN, BACKSPACE, or the Space Bar to move the \"#\" adjacent to the configuration description, and then press RUN.\nCHAPTER 3\nOPERATING A 2780, 3780, 3741, 2200-TO-2200, OR 2200 WPS EMULATION PROGRAM\n\n3.1 INITIAL OPERATOR ACTION\n\nTo operate the BSC 1 software, follow the instructions for loading the BSC 1 software (refer to Section 1.5). If no configurations have been previously saved, refer to Chapter 2 for instructions on how to create and save a communications configuration. A saved communications configuration is loaded from the BSC 1 main menu, which appears each time the BSC 1 software is loaded.\n\nDuring the configuration loading sequence, the screen momentarily clears, and the display shown in Figure 3-1 appears. This display summarizes the parameters for the configuration and shows the configuration name. When the loading sequence is completed, the screen displays the appropriate operator's screen.\n\n<table>\n<thead>\n<tr>\n<th>PARAMETER</th>\n<th>CURRENT SELECTION</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>MODEM TYPE</td>\n<td>(as specified)</td>\n</tr>\n<tr>\n<td>MODEM OPERATES</td>\n<td>(as specified)</td>\n</tr>\n<tr>\n<td>RECORD BLOCKING</td>\n<td>(as specified)</td>\n</tr>\n<tr>\n<td>RECEIVE TRANSPARENCY</td>\n<td>(as specified)</td>\n</tr>\n<tr>\n<td>MULTIPONT</td>\n<td>(as specified)</td>\n</tr>\n</tbody>\n</table>\n\n*******************************************************************************\n* LOADING SYSTEM WANG 2200 TELECOMMUNICATIONS *\n* (configuration name) *\n* INPUT = (software transmission module name and description) *\n* OUTPUT = (software reception module name and description) *\n*******************************************************************************\nMicrocode revision = (emulation) (microcode release number) (release date) (System type)\n\nFigure 3-1. BSC 1 Emulator Loading Sequence Display\nAfter the operator's screen appears, but before a connection with a remote site is established, ensure that all necessary peripheral devices are readied. Because data reception is activated by a data transmission from the remote end of a communications link, the designated reception device for a BSC 1 emulator should be ready before the remote end begins to transmit data. For this reason, the BSC 1 emulator automatically checks the ready status of designated reception devices. If a device is not ready, a message is displayed on the screen when the system first enters the Control mode.\n\nBe sure that the reception device is ready before establishing a connection with a host system or a terminal, unless no data is to be received. To ready a reception device, press SP'1 to activate the Attention mode, then respond to the device-related prompts (refer to Section 3.6). After the Attention mode prompt/response sequence is completed, the system automatically returns to the Control mode.\n\nDepending upon the communications application, a connection can now be established with a remote site. Appendix C presents additional information on establishing a connection.\n\nOnce a connection is established, the operation of a BSC 1 emulator can differ depending upon the peripherals selected and the communications functions performed. For example, the sequence of operations for a session requiring only transmission functions differs from that for a session involving both transmission and reception functions. For this reason, this chapter gives step-by-step procedures for each of the individual communications functions, instead of a general sequence of operations. Appendix E presents a general summary of the operations sequence for BSC 1 communications.\n\n3.2 OPERATIONAL MODES\n\nAny person attempting to operate a 2780, 3780, 3741, 2200-to-2200, or 2200 WPS emulation should first understand the operational modes available with the BSC 1 software. Each of these emulations provides 2-way communication utilizing the following five modes of operation: Control, Bid, Send, Receive, and Attention. Refer to Table 3-1 for descriptions of these operational modes. During program execution, a particular mode may be entered many times or not at all, depending upon the local transmission and reception requirements and the number of data transfers originating from the remote end of the communications link.\n\nOnly one operational mode is in effect at any time. For example, after a communications configuration is loaded into memory, the system automatically enters the Control mode and displays the word CONTROL on the operator's screen under the mode label. The mode label appears at the far right of the operator's screen.\n<table>\n<thead>\n<tr>\n<th>Mode</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Control</strong></td>\n<td>Automatically occurs when emulator execution begins. The system monitors the communications line and the keyboard. When the operator or the remote end initiates action, the system can enter another mode. The system remains in Control mode indefinitely if no actions are initiated.</td>\n</tr>\n<tr>\n<td><strong>Bid</strong></td>\n<td>Occurs from Control mode when SF'2 (SEND) or SF'3 (SEND TRSP) is pressed to initiate data transmission (refer to Section 3.7). Bid mode also occurs from Control mode when RETURN is pressed during keyboard message entry to transmit an entered message. The system then enters Bid mode and requests host permission to transmit. Bid mode continues until the host grants permission (the system then enters Send mode) or the BID request is aborted. Refer to Table 3-2 for information on BID abort.</td>\n</tr>\n</tbody>\n</table>\n| **Send** | Occurs from a successful Bid mode. The system transmits in EBCDIC code (for C/R or SF'2) or uses BSC control characters to activate transparent transmission (SF'3) until one of the following occurs. \n- All data is sent. \n- The local operator or remote end aborts transmission. \n- Transmission difficulties arise (such as a line disconnect). \nThe system then returns to Control mode. |\n| **Receive** | Occurs only if the remote end initiates transmission. The BSC 1 software routes received data to the designated device(s) until one of the following occurs. \n- An end-of-transmission code is received. \n- The local operator or remote end aborts transmission. \n- Transmission difficulties arise (such as a line disconnect). \nThe system then returns to Control mode. (Receive mode continues if an insufficient paper condition interrupts printer reception.) |\n| **Attention** | Occurs from Control mode when SF'1 is pressed. Attention mode is activated for one of three reasons. \n- To open a disk file for reception \n- To erase a file opened by the system \n- To adjust paper in the printer \nRefer to Table 3-3 for information on Attention mode prompts. |\nOnce in the Control mode, the system waits indefinitely if no action occurs at either the local or the remote end of the communications link. When an action, such as an operator response, causes the system to enter another mode, the new mode name is displayed. During each mode of operation, the currently active keyboard controls are displayed on the second line of the screen. For example, during the Control mode the first and second lines appear as in Figure 3-2.\n\n| ACTIVE KEYBOARD CONTROLS---2200 MVP BATCH EMULATOR |\n| '0=CONTROL '1=ATTN '2=SEND '3=SEND TRSP '30=Bknd C/R=KYBD |\n\nTRANSMISSION COMPLETED\n\nPRINTER NOT READY\n\n---MODEM SIGNALS--- BLOCKS BLOCKS\nDTR DSR RTS CTS CAR SENT RECD ---MODE---\n* * * 21 215 CONTROL\n\nFigure 3-2. Sample Operator Screen\n\nWhen the mode changes, the active keys (listed on Line 2) also change. Table 3-2 lists the active keys for Control, Bid, Send, and Receive modes; Table 3-3 lists the active keys for Attention mode.\n\nNote that a configuration can be loaded without establishing a connection; therefore, a user can examine most emulator operations and become familiar with the software before attempting on-line operation. If difficulty arises during program execution, check the screen to determine the current operational mode; then refer to the applicable tables in this chapter for information about the operation of that mode. If the difficulty persists, contact a Wang Customer Engineering representative or Wang Corporate Systems Support representative.\nTable 3-2. Active Keys for Control, Bid, Send, and Receive Modes\n\n<table>\n<thead>\n<tr>\n<th>Mode</th>\n<th>Active Keys</th>\n<th>Action</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CONTROL</td>\n<td>SF'0=CONTROL</td>\n<td>Removes any currently displayed status and error messages. The BLOCKS SENT and BLOCKS RECD values are retained until Send or Receive mode is activated.</td>\n</tr>\n<tr>\n<td></td>\n<td>SF'1=ATTN</td>\n<td>Activates the Attention mode, which allows reception devices to be readied, or printer paper adjustments to be made (refer to Section 3.6).</td>\n</tr>\n<tr>\n<td></td>\n<td>SF'2=SEND</td>\n<td>Initiates transmission in EBCDIC code. The software requests source-device information (refer to Sections 3.7 and 3.8). The system then enters Bid mode.</td>\n</tr>\n<tr>\n<td></td>\n<td>SF'3=SEND TRSP</td>\n<td>Initiates transparent transmission (using BSC line control characters that permit transmission in any code); otherwise, same as SF'2.</td>\n</tr>\n<tr>\n<td></td>\n<td>C/R=KYBD</td>\n<td>Carriage return (C/R) is activated by pressing RETURN. C/R allows single-record entry from the keyboard (refer to Section 3.9).</td>\n</tr>\n<tr>\n<td>BID</td>\n<td>SF'0=ABORT</td>\n<td>Terminates a Bid attempt. To recover from an aborted Bid attempt, press SF'31 to activate the Reset and Disconnect function; then press RUN and RETURN. To resume operations, dial the connection again.</td>\n</tr>\n<tr>\n<td>SEND</td>\n<td>SF'0=ABORT</td>\n<td>Terminates transmission. The system sends the last data block currently in memory, signals the remote end that transmission is aborted, and returns to the operator's screen in Control mode.</td>\n</tr>\n<tr>\n<td>RECEIVE</td>\n<td>SF'0=ABORT</td>\n<td>Terminates reception. The system signals the remote end that an Abort request has been made and follows the remote system Abort procedure. Press SF'0 to return to Control mode. (Host Abort procedures vary — one may clear the transmission, and another may attempt a partial transmission; therefore, a "cancel job request" or other host-acceptable keyboard message may be required in addition to the Abort signal.)</td>\n</tr>\n<tr>\n<td>Device</td>\n<td>Active Keys</td>\n<td>Action</td>\n</tr>\n<tr>\n<td>-------------------------</td>\n<td>-------------------</td>\n<td>------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Disk (Search method)</td>\n<td>SF'0=CONTROL</td>\n<td>Reactivates the Control mode.</td>\n</tr>\n<tr>\n<td></td>\n<td>SF'1=OPEN FILE</td>\n<td>Closes any currently open receive file and opens a new file for disk receive (refer to Section 3.6).</td>\n</tr>\n<tr>\n<td></td>\n<td>SF'2=ERASE FILE</td>\n<td>Erases either a currently open receive file (thereby freeing unused disk space), or a user-specified cataloged file (disk space is freed only if the file occupies the last currently used disk sectors). Refer to Section 3.6.</td>\n</tr>\n<tr>\n<td>Disk (On Error method)</td>\n<td>SF'0=CONTROL</td>\n<td>Reactivates Control mode; only SF'0 is active. Refer to Section 3.8 for On Error method disk receive prompts.</td>\n</tr>\n<tr>\n<td>Printer</td>\n<td>SF'0=CONTROL</td>\n<td>Reactivates the Control mode.</td>\n</tr>\n<tr>\n<td></td>\n<td>SF'12=PRT FMT TAPE</td>\n<td>A user can specify a software-controlled vertical tape format for printer output. Refer to Appendix G.</td>\n</tr>\n<tr>\n<td></td>\n<td>SF'13=FORM FEED</td>\n<td>Executes a printer form feed; the system then returns to Control mode.</td>\n</tr>\n<tr>\n<td></td>\n<td>SF'14=VERT. TAB</td>\n<td>Executes a printer vertical tab; the system then returns to Control mode.</td>\n</tr>\n<tr>\n<td></td>\n<td>SF'15=LINE FEED</td>\n<td>Executes a printer line feed; the system then returns to the Control mode.</td>\n</tr>\n<tr>\n<td>Disk and printer</td>\n<td></td>\n<td>The keys related to the disk access method (Search or On Error) are active initially. After the disk-related operations have been completed, the keys related to printer operation are active.</td>\n</tr>\n</tbody>\n</table>\n3.3 DISPLAYS, PROMPTS, AND STATUS MESSAGES\n\nThe BSC 1 emulators use screen prompts, status messages, and error messages to request responses or provide information during emulator operation. The particular locations where specific types of information appear on the screen are shown in Figure 3-3. (Line Numbers 1 through 13 in the figure are used to simplify discussion of the screen layout; they do not appear on the screen.) Screen labels that remain unchanged for all operational modes are shown as uppercase words in Figure 3-3 (Lines 1, 11, and 12); Lines 3 and 10 are always blank.\n\n<table>\n<thead>\n<tr>\n<th>Line</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>ACTIVE KEYBOARD CONTROLS</td>\n</tr>\n<tr>\n<td>2</td>\n<td>(List of active keys for operating mode.)</td>\n</tr>\n<tr>\n<td>3</td>\n<td>(Send status messages. Receive-device prompts. Input scale.)</td>\n</tr>\n<tr>\n<td>4</td>\n<td>(Send-device prompts. System action during reception. Input line.)</td>\n</tr>\n<tr>\n<td>5</td>\n<td>(Send-file-name error messages.)</td>\n</tr>\n<tr>\n<td>6</td>\n<td>(Receive-device ready/not-ready status messages.)</td>\n</tr>\n<tr>\n<td>7</td>\n<td>(Automatic receive-file-opening error messages.)</td>\n</tr>\n<tr>\n<td>8</td>\n<td>(Reception abort messages.)</td>\n</tr>\n<tr>\n<td>9</td>\n<td>--MODEM SIGNALS--</td>\n</tr>\n<tr>\n<td>10</td>\n<td>BLOCKS BLOCKS</td>\n</tr>\n<tr>\n<td>11</td>\n<td>DTR DSR RTS CTS CAR SENT RECD --MODE--</td>\n</tr>\n<tr>\n<td>12</td>\n<td>* * * * * xxxx yyyy mmmmmm mmmm</td>\n</tr>\n</tbody>\n</table>\n\nFigure 3-3. Operator Screen, General Format\n\nSome displayed information is device-independent and other information is device-dependent. Some information is common to all operational modes, and other information is related only to specific modes. For example, as indicated in Section 3.2, the active SF keys for an operational mode are listed on Line 2 while that mode is in effect. Five SF keys are active during the Control mode; only one SF key is active during the Send, Bid, or Receive mode. The number of SF keys that are active during the Attention mode depends upon the reception device(s) designated for the configuration. Figure 3-2 provides an example of the active keyboard controls during Control mode.\n\nTransmission and reception status messages are displayed on Lines 4 and 9 in the screen layout (refer to Table 3-4). Line 4 also displays a 63-byte scale during keyboard send operations.\nTable 3-4. Transmission/Reception Status Messages\n\n<table>\n<thead>\n<tr>\n<th>Location</th>\n<th>Message*</th>\n<th>Meaning</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Line 4</td>\n<td>SEND</td>\n<td>The system is either sending or waiting to send data automatically translated into EBCDIC code.</td>\n</tr>\n<tr>\n<td></td>\n<td>TRANSPARENT</td>\n<td>The system is either sending or waiting to send transparent data (no translation is made).</td>\n</tr>\n<tr>\n<td></td>\n<td>TRANSMISSION COMPLETED</td>\n<td>The system has completed a send (SF'2) or a send transparent (SF'3) operation.</td>\n</tr>\n<tr>\n<td></td>\n<td>TRANSMISSION ABORTED</td>\n<td>Transmission has been aborted in response to action by the local or remote operator.</td>\n</tr>\n<tr>\n<td>Line 9</td>\n<td>RECEPTION ABORTED</td>\n<td>Transmission from a remote system has been aborted in response to action by the local or remote operator.</td>\n</tr>\n</tbody>\n</table>\n\n* Since message retention eliminates the necessity for constant operator monitoring, existing messages on Lines 4 and 9 are not cleared when the system returns to the Control mode after transmission or after reception is either completed or aborted. To remove such messages, press SF'0 while the system is in Control mode.\n\nLine 5 in Figure 3-3 displays prompts related to the input device after SF'2 or SF'3 is pressed to initiate transmission. These prompts and the acceptable responses are discussed in Section 3.6. Line 5 is also used to display keyboard-entered messages during keyboard send operations (refer to Section 3.9).\n\nLine 7 displays receive-device ready/not-ready status messages. These messages are always related to the designated reception device for the executing configuration. For example, if the receive device is a printer that is not ready, the message PRINTER NOT READY appears on Line 7; no message appears if a ready condition exists. Figure 3-2 shows a receive-device status message on Line 7, indicating that the system printer has not been readied for reception.\n\nLines 12 and 13 present information for five modem signals: DTR (Data Terminal Ready), DSR (Data Set Ready), RTS (Request To Send), CTS (Clear To Send), and CAR (Carrier). An asterisk appearing on Line 13 below a modem signal name on Line 12 represents an active status for that modem signal. To indicate the rapidly changing status of the RTS, CTS, and CAR modem signals during transmission and reception, the asterisks blink on and off. Figure 3-2 provides an example of this display with DTR, DSR, and CAR active. The significance of the modem categories is summarized in Table 3-5.\n<table>\n<thead>\n<tr>\n<th>Signal</th>\n<th>Definition</th>\n<th>Status</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>DTR</td>\n<td>Data Terminal Ready</td>\n<td>An asterisk indicates that the communications controller is operational (microcode has been loaded by the emulation program).</td>\n</tr>\n<tr>\n<td>DSR</td>\n<td>Data Set Ready</td>\n<td>An asterisk indicates that the modem has been placed in the data position. Although DSR must be present for data transmission or reception to occur, its presence does not always ensure a viable communications link. With some modems, DSR may be activated while the local modem is in the data position and the remote end either has not yet completed the link or has disconnected an established link.</td>\n</tr>\n<tr>\n<td>RTS</td>\n<td>Request To Send</td>\n<td>An asterisk indicates that a Request To Send signal is being sent from the communications controller to the modem.</td>\n</tr>\n<tr>\n<td>CTS</td>\n<td>Clear To Send</td>\n<td>An asterisk indicates that the modem is signaling the controller that the modem is ready to send data.</td>\n</tr>\n<tr>\n<td>CAR</td>\n<td>Carrier</td>\n<td>An asterisk indicates that carrier (the sine wave that carries the transmitted or received signal) is present.</td>\n</tr>\n</tbody>\n</table>\n\nIn Line 13 of Figure 3-3, xxxx and yyy represent the number of blocks sent and the number received, respectively. Initially these values are blank on the display. A value is displayed in the xxxx position when the system enters the Send mode for the first time and actually transmits data. This category is initially set to 0000, and is increased by 1 as each block is transmitted. After the transmission is completed, the xxxx value indicates the total number of blocks sent, and remains fixed (refer to Figure 3-2). This value is not altered by system entry into the Control, Receive, Attention, or Bid mode. When the system again enters the Send mode, the xxxx value is reset to 0000.\nSimilarly, during receive operations no value is displayed in the yyyy position on Line 13 of the screen until the system enters the Receive mode in response to a data transmission from the remote end of the communications link. When reception begins, yyyy is set to 0000 and increased by 1 after each block is received. After reception is completed, the yyyy value indicates the total number of blocks received; this value remains fixed until the next entry into Receive mode, which resets the value to 0000 (refer to Figure 3-2).\n\nAt the far right of Line 13 in Figure 3-3, the current operational mode is represented by mmmmmmmm. In Figure 3-2, for example, the current mode is CONTROL.\n\n3.4 SPECIAL CONSIDERATIONS FOR 2200-TO-2200 OPERATION\n\nBecause the 2200-to-2200 protocol is intended for use with 2200 Series products on both ends of the communications link, the operation of this software differs slightly from that of the other BSC 1 emulators. The 2200-to-2200 protocol utilizes the Search disk access method (On Error disk access is not available). Also, the 2200-to-2200 protocol does not support printer operations; only disk operations are used for transmission and reception (console messages are received to the screen only).\n\nThe 2200-to-2200 protocol is essentially a 2780 protocol that utilizes transparent mode operations, with modifications to support Wang file formats; therefore, files sent and received need not be formatted in Wang TC file format. The 2200-to-2200 protocol supports the transfer of both data and program files without conversion.\n\n3.5 SPECIAL CONSIDERATIONS FOR 2200 WPS MODE OPERATION\n\nThe 2200 WPS mode can be used by Wang 2200 systems with 2200 Word Processing software to communicate with Wang 2200 Word Processing, OIS, WP, and VS/IIS (Integrated Information Systems) systems if each system is equipped with synchronous communications capabilities. There are, however, several prerequisites for the 2200 WPS mode to be used for document transfer. For any documents received to the 2200 system to be usable, that system must be equipped with 2200 Word Processing software and at least one 2236DW Integrated Terminal. The 2200 Word Processing software is also required if a 2200 system is to format documents for transmission using 2200 WPS mode.\n\nThe primary reason for these software and equipment requirements is the need to perform file format conversion to allow standard Wang word processing files to be processed by the BSC 1 software. Word processing files resident on a 2200 system must be converted to 2200 TC/WP file format in order to be accurately transmitted. Word processing files received by a 2200 system must be converted from 2200 TC/WP file format to WP format in order to be processed by the 2200 Word Processing software. The 2200 Word Processing software includes two utilities to perform these conversions.\n1. The Convert WP Document to TC Data File utility allows an operator to convert a WP document to 2200 TC/WP file format. A copy of the document is written in 2200 TC/WP file format to a 2200 TC/WP file with an operator-specified file name (the original WP document is unaffected by the conversion).\n\n2. The Convert TC Data File to WP Document utility converts a 2200 TC/WP file to 2200 WP document file format. A copy of the TC/WP file is written in WP document format to a document with an operator-specified name (the original TC/WP file is unaffected by the conversion).\n\nOperating instructions for these two utilities are contained in the 2200 Word Processing Software Operator's Guide (700-6937).\n\n**NOTE**\n\nThese utilities must be used off-line, either before transmission or after reception. They cannot be used during the operation of the BSC 1 software.\n\nThe 2200 WPS mode utilizes the Search method of disk access (On Error disk access is not available). Also, the 2200 WPS mode does not support printer operations -- transmission and reception are to disk only (console messages are received to CRT only).\n\n### 3.6 DISK FILE RECEIVE OPERATIONS\n\nWhen Attention mode is activated from Control mode by the pressing of SF'1, the file opening and closing options allow up to 99 received files to be uniquely named. The operation of the Attention mode for file receive operations differs according to the disk access method chosen during the configuration process (refer to Section 2.4). The two disk access methods that can be chosen during the configuration process are Search and On Error. These disk access methods handle invalid responses to Attention routine prompts in different ways. The Search method searches for and validates operator-entered file names, and provides recovery if invalid responses are entered. The On Error method provides only BASIC-2 ERROR statement termination if invalid responses are entered. This method prevents, to some extent, the occurrence of non-recoverable BASIC-2 error codes, and therefore avoids the need to reload the emulator on most miscues. The On Error method should be used only when the emulator must run in an 11K partition or when no disk access is required.\n\n**Opening a Receive File Using the Search Disk Access Method**\n\nTo create and open a file for data reception to disk when using the Search disk access method, perform the following steps.\n1. Press SF'1 to activate Attention mode from Control mode.\n\n2. The following display then appears on Lines 1 and 2 of the operator screen. If the configuration includes printer receive capabilities, additional printer-related options also appear on Line 2.\n\n ACTIVE KEYBOARD CONTROLS---2200 MVP BATCH EMULATOR\n '0 = CONTROL '1=OPEN RCV FILE '2=ERASE FILE\n\n From this display, press SF'1 to open a receive file. The software erases any previously opened BSC 1 receive file.\n\n3. The prompt ENTER RECEIVE DISK ADDRESS appears on the screen. Enter the device address of the disk chosen for receive files and press RETURN.\n\n4. If an invalid disk address is entered, the software repeats the prompt in Step 3 until a valid address is entered. The software verifies that the disk is mounted and accessible, and then displays both the number of available sectors on the chosen disk and a prompt requesting a receive file name. For example, if Disk B20 is specified and 43,847 sectors are available in the B20 catalog area, the following display appears.\n\n ACTIVE KEYBOARD CONTROLS---2200 MVP BATCH EMULATOR\n '0 = CONTROL\n 43847 Sectors available on disk B20\n\n ENTER 1- TO 6-CHARACTER FILE NAME\n\n5. Enter a file name of six or fewer characters, and press RETURN. (The software uses this name to create a receive file.)\n\n The message SEARCHING CATALOGUE appears momentarily. If the entered name is already cataloged on the disk, the software cannot create a receive file with that name, and a different file name must be chosen; the message ROOT xxxxxxxx CATALOGUED appears (xxxxxxx is replaced by the file name), and the prompt ENTER 1- TO 6-CHARACTER FILE NAME is again displayed. If this occurs, repeat Step 5.\n\n If the entered name is acceptable, the system returns to Control mode automatically, and the message RECEIVE FILE xxxxxxx01 OPENED appears, indicating that the first file is now open. The temporarily allotted file size of the opened receive file equals all the remaining platter space (the disk is not available to other users for the creation of new files).\n\n The system appends two digits (e.g., 01, 02, 03) to the file name when the file is opened. The 2-digit sequence appended to the operator-supplied name accommodates multiple file reception, because the sequence is increased each time a new file is opened by the software. Thus, if the root file name \"DATA\" is entered, the first file received is named \"DATA 01\", and the next file received is named \"DATA 02\".\n\n3-12\nOpening a Receive File Using the On Error Disk Access Method\n\nTo open a file for data reception to disk when using the On Error disk access method, perform the following steps.\n\n1. Press SF'1 to activate Attention mode from Control mode.\n\n2. The following display then appears.\n\n ACTIVE KEYBOARD CONTROLS—2200 MVP BATCH EMULATOR\n '0 = CONTROL\n\n ENTER RECEIVE DISK ADDRESS 1=310 2=B10 3=320 4=B20 5=350?\n\n Respond by entering the number corresponding to the appropriate device address and pressing RETURN.\n\n3. The prompt ENTER 1- TO 6-CHARACTER FILE NAME? then appears. Enter a file name of six or fewer characters, and press RETURN.\n\n4. The prompt ENTER NUMBER OF SECTORS TO OPEN RECEIVE FILES then appears. The On Error method requires that the number of sectors of disk space for each receive file be pre-assigned. Enter the desired number of sectors and press RETURN.\n\n After a response to this prompt is entered, the system appends the digits 01 to the operator-supplied file name before checking the receive disk catalog. If the file name is cataloged on the receive disk, the message STOP NAME ALREADY CATALOGUED appears. The software terminates the receive file opening operation without opening a file. If this occurs, press SF'0 to resume emulator operations and then initiate the receive file opening sequence again, if appropriate.\n\n If the file name entered is not cataloged on the receive disk, the software opens a file for reception, and displays the message RECEIVE FILE xxxxxxx01 OPENED. The file created by this process is allotted a number of sectors equal to the operator-supplied value. The system then returns to Control mode.\n\nThe Erase File Function\n\nThe Erase File function is active only in configurations using the Search disk access method. Two types of files can be erased using the Erase File function: the last file opened by Attention mode (erasing the file frees unused disk space reserved by the emulator) and any cataloged file (space is freed only if the file occupies the last currently used disk sectors). To activate the Erase File function, perform the following steps.\n\n1. Press SF'1 to activate Attention mode from Control mode.\n\n2. Press SF'2. If a disk receive file is currently open, the Erase File function erases that file, and automatically reactivates Control mode.\n3. If no disk receive file is currently open, the Erase File function allows any cataloged file to be erased. The prompt ENTER RECEIVE DISK ADDRESS appears. Enter a valid disk address. The prompt ERASE FILE ______ then appears. Enter the name of any file cataloged on the disk specified in the ENTER RECEIVE DISK ADDRESS prompt, and press RETURN.\n\n4. The messages SEARCHING FOR FILE and FILE xxxxxxxx ERASED (with the appropriate name substituted for xxxxxxxx) appear, and the system returns to Control mode.\n\nThe Erase File function should be used to erase unused open receive files after receive operations are completed. The software automatically opens consecutive receive files when the Search disk access method is used: after each received file has been closed by the software, the software automatically opens a new receive file. Therefore, after receive operations have been completed, an additional, empty receive file will have been opened. This file should be closed and erased to conserve disk space and to free the disk for file creation operations by other users.\n\n3.7 DISK FILE SEND OPERATIONS\n\nDisk file Send mode is activated from Control mode by pressing SF'2 (for normal send) or SF'3 (for transparent send). Send mode operations differ according to the disk access method chosen during the configuration process. The two disk access methods that can be chosen during the configuration process are Search and On Error. These disk access methods involve different ways of handling invalid responses to disk file send routine prompts. The Search disk access method searches for and validates operator-entered file names, and provides recovery if invalid responses are entered. The On Error disk access method provides only program termination using the BASIC-2 ERROR statement if invalid responses are entered. This method prevents, to some extent, the occurrence of non-recoverable BASIC-2 error codes, and therefore avoids the need to reload the emulator on most miscues. It should be used only when it is imperative that the emulator run in an 11K partition.\n\nSending a File Using the Search Disk Access Method\n\nTo queue a TC-formatted file for data transmission from disk when using the Search disk access method, perform the following steps.\n\n1. Press SF'2 or SF'3 from Control mode. Pressing SF'2 initiates transmission in EBCDIC. Pressing SF'3 initiates transmission in BSC Transparent mode.\n\n2. The following display then appears.\n\n```\nACTIVE KEYBOARD CONTROLS----2200 MVP BATCH EMULATOR\n'O = ABORT\n\nSEND\nENTER SEND DISK ADDRESS____\n```\nIf SF'3 is pressed, Line 4 reads SEND TRANSPARENT.\n\n3. Enter a valid disk address and press RETURN. The following message appears (the actual disk address entered in response to the previous prompt appears where yyy is shown; initially, x is 1).\n\n\\[\n\\text{SEND (file name) from disk yyy} \\\\\n\\text{ENTER FILE NAME x ?}\n\\]\n\n4. Enter the name of the file to be transmitted. The system then searches the catalog to determine the validity of the name. If the file name is not valid, the message REENTER appears below the prompt; continue operations by entering a valid file name. If the file name is valid, the software increases the x value by 1 and then requests the name of the next file to be transmitted by repeating the ENTER FILE NAME prompt. The process continues until either RETURN is pressed without a file name being entered, or the x value reaches 10.\n\n5. The prompt SEND FILES SEPARATELY OR COMBINED AS ONE (1=SEPARATE) then appears if more than one file is named for transmission. There are two possible choices.\n\na. Press 1 and RETURN if the files are to be sent as separate files within a single transmission.\n\nb. Press RETURN if the files are to be combined and sent as a single file. If this option is chosen, the transmission appears to the remote end as though the multiple files originated as a single file or stream of cards.\n\nAfter the prompt and response sequence is completed, the system enters the Bid mode, waiting for host acknowledgment. From a successful Bid mode, the system automatically enters the Send mode and transmits the specified files before returning to the Control mode. The software remains in Bid mode indefinitely if no further communications activity occurs.\n\nSending a File Using the On Error Disk Access Method\n\nTo queue a TC-formatted file for data transmission from disk using the On Error disk access method, perform the following steps.\n\n1. Press SF'2 or SF'3 from Control mode. Pressing SF'2 initiates transmission in EBCDIC. Pressing SF'3 initiates transmission in BSC Transparent mode.\n\n2. The following display then appears.\n\n\\[\n\\text{ACTIVE KEYBOARD CONTROLS---2200 MVP BATCH EMULATOR} \\\\\n'0 = ABORT} \\\\\n\\text{SEND} \\\\\n\\text{ENTER SEND DISK ADDRESS 1=310 2=B10 3=320 4=B20 5=350?}\n\\]\nIf SF'3 is pressed, Line 4 will read SEND TRANSPARENT.\n\n3. Enter the number corresponding to the appropriate disk address and press RETURN.\n\n4. The following message appears.\n\n SEND\n ENTER FILE NAME x ?\n\nInitially, x is 1. Supply the name of the file to be transmitted. The system then searches the catalog to determine the validity of the name. If the file name is not valid, the message STOP NAME NOT CATALOGUED appears. If this occurs, press SF'0 to return to Control mode, press SF'2 or SF'3, and begin the file send sequence again; all file names must be reentered.\n\nIf the file name is valid, the software increases the x value by 1 and then requests the name of the next file to be transmitted by repeating ENTER FILE NAME. The process continues until either RETURN is pressed without a file name being entered, or the x value reaches 5.\n\n5. The prompt SEND FILES SEPARATELY OR COMBINED AS ONE 1=SEPARATE then appears if more than one file is named for transmission. There are two possible choices.\n\n a. Press 1 and RETURN if the files are to be sent separately within a single transmission.\n\n b. Press RETURN if the files are to be combined and sent as a single file. If the option to combine the files is chosen, the transmission appears to the remote end as though the multiple files originated as a single file or stream of cards.\n\nAfter the prompt and response sequence is completed, the system enters the Bid mode, waiting for host acknowledgment. From a successful Bid mode, the system automatically enters the Send mode and transmits the specified files before returning to the Control mode. The software remains in Bid mode indefinitely if no further communications activity (such as host acknowledgment) occurs.\n\n3.8 CARD SEND OPERATIONS\n\nIf a 2780, 3780, or 3741 emulator is configured to support a card reader as an input device, Card Send can be selected from Control mode. When SF'2 or SF'3 is pressed during Control mode, the following display appears.\nACTIVE KEYBOARD CONTROLS—2200 MVP BATCH EMULATOR\n'0 = ABORT\nSEND\nEND OF FILE AT HOPPER EMPTY 1=YES?\n\nIf SF'3 is pressed, Line 4 reads SEND TRANSPARENT.\n\nTo begin card send operations, perform the following steps.\n\n1. Press 1 and RETURN to answer yes, or RETURN only to answer no. A yes answer indicates that only one group of cards is to be sent; a no answer implies that more than one group of cards is to be sent. This prompt appears initially and after each Hopper Empty condition relayed to the software by the card reader, unless the Hopper Empty condition occurs following a yes answer to the prompt. If a Hopper Empty condition is relayed to the software and this prompt is answered yes, the software returns to Control mode.\n\n2. After a yes or no response is entered, the prompt READY CARD READER. KEY RETURN TO CONTINUE? appears. This prompt allows the card reader to be readied to begin (or continue) transmission. After the card reader is readied, press RETURN to begin (or continue) the transmission sequence.\n\n3.9 KEYBOARD SEND OPERATIONS\n\nThe 2780, 3780, 3741, 2200-to-2200, and 2200 WPS Mode emulators provide the capability to transmit messages entered at the 2200 terminal. This capability is useful for sending sign-on messages or status request messages to a host system. Keyboard entry capabilities are available during Control mode, and are denoted in Line 2 of the Control mode display as C/R (carriage return), as shown below.\n\nACTIVE KEYBOARD CONTROLS\n'0 = CONTROL '1 = ATTN '2 = SEND '3 = SEND TRSP C/R = KYBD\n\nTo send a message from the keyboard, perform the following steps.\n\n1. Press RETURN to activate the C/R routine. C/R allows single-record entry from the keyboard. A position-scale (63 characters long) is displayed on Line 4 of the screen, and each entered character appears beneath this scale; the BACKSPACE and Line Erase keys are active for editing the message.\n\n2. After the text is complete and correct, press RETURN to signify end-of-message and start transmission.\n\nTo return to Control mode without sending a message, press SF'0.\n3.10 ERROR MESSAGES AND RECOVERY TECHNIQUES\n\nVarious error messages can occur during BSC 1 emulator operations. Most messages appear during On Error disk access operations as the result of an incorrect response to a prompt. Error recovery is not difficult in most cases, but some of the interrupted operations will need to be repeated. This section discusses only those messages most likely to occur during normal operations.\n\nInvalid File Names (Transmission)\n\nAs indicated in Section 3.7, an error message may occur when the system is processing operator-supplied names of disk files to be transmitted. If the Search disk access method is being used, an invalid file name produces the message REENTER. With the Search method, recovery requires only that a new, unique file name be entered.\n\nIf the On Error disk access method is being used, an invalid file name produces the message STOP NAME NOT CATALOGUED. To reactivate emulator operations, perform the following steps.\n\n1. Press SF '0 to return to Control mode.\n2. Press SF '2 or SF '3 to reinitiate the desired transmission operation.\n3. Enter valid responses to the input device prompts.\n4. Reenter each of the valid file names entered previously.\n\nInvalid File Names (Reception)\n\nAs indicated in Section 3.6, an error message can occur during the Attention mode when the system is processing the operator-supplied file name for receive-to-disk files. If the Search method is in effect, the system searches the catalog index to ensure that the file name is valid (has not been previously cataloged). The software appends a 2-digit sequence code to the operator-supplied characters; thus, the software has the capability to open as many as 99 sequentially named files. An invalid file name produces the message xxxx xxxxxxx CATALOGUED RE-ENTER. Recovery for the Search method requires only that a new, unique file name be entered.\nIf the On Error disk access method is being used, an invalid file name produces the message STOP NAME ALREADY CATALOGUED. To reactivate emulator operations, perform the following steps.\n\n1. Press SF'0 to return to Control mode.\n2. Press SF'1 to reinitiate the Attention mode.\n3. Enter valid responses to the reception device prompts.\n\nInsufficient Disk Space (Reception)\n\nOther error messages can occur during or after Attention mode operations, when the system attempts to open a file but cannot do so because of disk space limitations. For example, the message INSUFFICIENT SPACE ON RECEIVE DISK can occur at the time the first file is being opened if the Search method is in effect. If the On Error method is in effect, the message STOP INSUFFICIENT SPACE ON RECEIVE DISK can occur. Such a message can also occur during multiple file reception when one file is closed and the next file is being opened. To resume emulator operations, perform the following steps.\n\n1. Press SF'0 to return to Control mode.\n2. If a diskette is being used for reception, remove the filled diskette and mount another indexed diskette in the same drive.\n3. As an alternative, use the Attention mode prompts to select a platter that has sufficient space.\n4. Supply a new file name for reception of additional files from the remote end.\n a. If the Search method is in effect, press SF'1 to enter Attention mode, and then enter a new file name.\n b. If the On Error method is in effect, press SF'0 to return to Control mode; then press SF'1 to enter Attention mode, and enter a new file name.\n\nInsufficient File Space (Reception)\n\nIn Receive mode, the error message ERR D81 occurs if the file being received to disk overflows its allotted space, whether the Search or On Error method is in effect. Remember that the Search method opens each receive file by temporarily allotting all the remaining platter space; any unused space is freed when the file is closed. Therefore, an ERR D81 message probably indicates that the receive disk is nearly full and that there was not enough disk storage space to store the most recently received file. On the other hand, the On Error method opens each receive file by allotting the exact number of sectors specified by the operator and does not free unused space when closing the file. Therefore, the message TEXT OVERFLOW means that an ERR D81 condition has occurred, indicating either that the receive disk is nearly full or that the allotted file space was not sufficient to store the most recently received file.\nThe system remains in the Receive mode if reception to disk is interrupted by an ERR D81 message. Although repeated pressing of SF'0 can return the system to Control mode, such a procedure is not a recommended recovery technique. Instead, perform the following steps.\n\n1. Press CLEAR, and then press RETURN.\n\n2. Reload the BSC 1 software (refer to Section 1.5).\n\n3. Reload the emulation configuration (refer to Section 2.6).\n\n4. Contact the remote end of the line to request retransmission of all files, and provide ample space on the receiving disk platter.\n\nSystem Errors\n\nIf the message SYSTEM ERROR! occurs during the loading or executing of a configuration, clear the system and reload the program. To avoid one source of such an error, do not press the HALT/STEP key, followed by SF'0, when the system is in the Send mode. Also, do not press RESET at any time during program execution. If repeated attempts to operate a program produce a system error, call a Wang Customer Engineering representative.\n\n3.11 BACKGROUND OPERATION (2200MVP OR 2200LVP PROCESSOR)\n\nDuring the running of a 2780, 3780, 3741, 2200-to-2200, or 2200 WPS emulator on a 2200MVP or LVP system, communications functions that can be accomplished without operator intervention can be executed in a background partition. Pressing SF'30 releases the terminal to an available partition. Normal emulator operations continue in the original partition, utilizing any I/O devices previously selected by the operator. Transmission and reception functions can be initialized prior to entry into background mode, with actual transmission or reception taking place in background. To return the emulator to foreground operation, the $RELEASE TERMINAL command must be used to return the partition running the emulator to operator control. The emulator then detects the terminal status change and resumes normal foreground operations.\n\nIf, for example, an operator is running a 3780 configuration and wishes to have emulator operations performed in a background partition, the operator should press SF'30. The 3780 emulator operations continue in background, and the operator's terminal is attached to the next available partition. If no partition is available, the emulator does not release the terminal.\n\nWhen communications functions are to be executed in background mode, any devices selected to receive data should be enabled to allow receive operations to take place without operator intervention. If receive devices are not enabled to allow reception without operator intervention, reception is suspended.\nNOTE\n\nBecause the BSC 1 software uses different sets of $GIO statements for emulation operations on 2200MVP and 2200VP processors, the emulators cannot run on an MVP running in VP mode. The software Loading module begins normal MVP operations, causing $GIO failures on the system operating in VP mode.\nCHAPTER 4\nOPERATING A HASP MULTILEAVING COMMUNICATIONS PROGRAM\n\n4.1 INITIAL OPERATOR ACTION\n\nThe BSC 1 software must be loaded before the operation of a HASP emulation configuration begins (refer to Section 1.5). After the Load a Configuration option for a HASP emulation configuration is selected, the display shown in Figure 4-1 appears while the system loads the emulation configuration. This display summarizes the user-specified parameters and shows the configuration name.\n\n<table>\n<thead>\n<tr>\n<th>MultiLeaving HASP Parameters</th>\n<th>CURRENT SELECTION</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>INPUT DEVICE</td>\n<td>(Input device - DISK or CARD READER)</td>\n</tr>\n<tr>\n<td>TRANSPARENT SEND?</td>\n<td>(As specified)</td>\n</tr>\n<tr>\n<td>PRINT STREAMS TO</td>\n<td>(As specified)</td>\n</tr>\n<tr>\n<td>PUNCH STREAMS TO</td>\n<td>(As specified)</td>\n</tr>\n<tr>\n<td>T.C. BOARD ADDRESS</td>\n<td>(As specified)</td>\n</tr>\n</tbody>\n</table>\n\n*LOADING SYSTEM WANG 2200 TELECOMMUNICATIONS*\n\n(figure name)\n\nMicrocode revision = HASP (Release number) (Release date)\n\nFigure 4-1. HASP Emulator Loading Sequence\n\n4.2 THE HASP EMULATOR DISPLAY\n\nDuring the loading sequence, the HASP emulator microcode is loaded into the communications controller, and the requested emulation configuration is loaded into the system. The HASP emulator display (shown in general format in Figure 4-2) then appears on the screen.\nFigure 4-2. HASP Emulator Display General Format\n\nThe display in Figure 4-2 occurs during normal HASP interaction. Print data streams are directed either to disk storage or to the printer at Device Address 215, depending on the options chosen during the configuration process. If disk receive operations are selected during configuration, punch data streams received from the host system are written to an opened receive disk file. Incoming messages from the host system activate the Console Output mode (refer to Section 4.3). Table 4-1 provides a key to the general format presented in Figure 4-2.\n\nNOTE\n\nIf the loaded configuration includes disk receive capabilities (if parameters were chosen to direct either print or punch streams to disk during configuration generation), two prompts relative to disk receive functions automatically appear during the emulator loading sequence, after the HASP emulator display appears on the screen. Section 4.6 has information on these prompts and the operator responses they require.\nTable 4-1. Key to HASP Emulator Display General Format\n\n<table>\n<thead>\n<tr>\n<th>Code</th>\n<th>Meaning</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>aaaaaaaa</td>\n<td>Receive disk status</td>\n</tr>\n<tr>\n<td>nameBccc</td>\n<td>Receive disk file name -- file name/alphabetic volume designator/file number (001-999)</td>\n</tr>\n<tr>\n<td>eeee</td>\n<td>Receive disk device address</td>\n</tr>\n<tr>\n<td>ffffffff</td>\n<td>Receive file status information</td>\n</tr>\n<tr>\n<td>mmmmmmmmmm</td>\n<td>Send device status</td>\n</tr>\n<tr>\n<td>filename</td>\n<td>Current send file name</td>\n</tr>\n<tr>\n<td>pppp</td>\n<td>Send device type</td>\n</tr>\n<tr>\n<td>qqqq</td>\n<td>Send device address</td>\n</tr>\n<tr>\n<td>rrrrrrrrrrr</td>\n<td>2200 error messages and status information</td>\n</tr>\n</tbody>\n</table>\n\nA sample HASP emulator display is shown in Figure 4-3, with typical messages and entries filled in. Not all display categories shown in the HASP emulator display are used during all emulator functions. In Figure 4-3, for example, the receive disk status message is \"Not Open,\" indicating that no receive disk file is open at this point in the operation. In fact, no address has yet been chosen for a receive disk. Note that a receive print operation has been suspended by the HASP operator. Also, a file named D-FILE is being sent from Disk 320 to a host system.\n\n<table>\n<thead>\n<tr>\n<th>HASP WORK STATION EMULATOR</th>\n<th>ACTIVE S.F. KEYS</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'0'=Control</td>\n<td>'1'=ATTN</td>\n</tr>\n<tr>\n<td>'2'=Send</td>\n<td>'3'=Console</td>\n</tr>\n<tr>\n<td>'4'=Signon</td>\n<td>'6'=Print</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>STATUS</th>\n<th>File</th>\n<th>STREAM</th>\n<th>DEVICE</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Not Open</td>\n<td>Rcv Disk</td>\n<td>None</td>\n<td></td>\n</tr>\n<tr>\n<td>Suspended</td>\n<td>Rcv Print</td>\n<td>215</td>\n<td></td>\n</tr>\n<tr>\n<td>Sending</td>\n<td>D-FILE</td>\n<td>Send Disk</td>\n<td>320</td>\n</tr>\n</tbody>\n</table>\n\nFigure 4-3. Sample HASP Emulator Display\nThe HASP workstation emulation utilizes five modes of operation: Control, Attention, Send, Console, and Sign-On. During program execution, a particular mode can be entered many times or not at all, depending upon the local transmission and reception requirements and the number of data transfers originating from the remote end of the communications link. Several modes also have subordinate functions that can be accessed after the mode is entered.\n\nWhen the HASP emulator display initially appears, the emulator is in Control mode. Once in Control mode, the system waits indefinitely if no action occurs at either the local or remote end of the communications link. When an action, such as a response to a prompt, causes the system to enter another mode, the second line of the screen displays either the currently active keyboard controls for that mode or any prompt that requires a response. During the Control mode, for example, the first and second lines appear as follows.\n\n<table>\n<thead>\n<tr>\n<th>HASP WORK STATION EMULATOR</th>\n<th>ACTIVE S.F. KEYS</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'0'=Control</td>\n<td>'1'=ATTN '2'=Send '3'=Console '4'=Signon '5'=EOF '6'=Print</td>\n</tr>\n</tbody>\n</table>\n\nAll the other modes can be accessed from the Control mode display. Control mode also provides two subordinate functions: Print and EOF. The modes and functions accessed from Control mode are detailed in Table 4-2. Note that '6'=Print does not appear in this display if the emulator is configured to direct all streams to disk; also, '5'=EOF appears in this display only if the emulator is configured for card send.\n\nTable 4-2. Active SF Keys, HASP Control Mode\n\n<table>\n<thead>\n<tr>\n<th>Key</th>\n<th>Function</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'0'</td>\n<td>Control</td>\n<td>Clears the screen and returns to the emulator display.</td>\n</tr>\n<tr>\n<td>'1'</td>\n<td>ATTN</td>\n<td>Calls the Attention routine for off-line disk receive processing (to open disk files and assign receive file names). If SF'1 is pressed, the Attention mode display appears. If disk receive is not selected during configuration, SF'1 is inactive. Attention prompts are discussed in Section 4.6.</td>\n</tr>\n<tr>\n<td>'2'</td>\n<td>Send</td>\n<td>Activates request for card or disk send, whichever was selected for the configuration currently running.</td>\n</tr>\n<tr>\n<td>'3'</td>\n<td>Console</td>\n<td>Activates the Console Entry routine for the entry of a console message or sign-off message.</td>\n</tr>\n</tbody>\n</table>\nTable 4-2. Active SF Keys, HASP Control Mode (continued)\n\n<table>\n<thead>\n<tr>\n<th>Key</th>\n<th>Function</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'4</td>\n<td>Signon</td>\n<td>Activates the Console Entry routine for the entry of a sign-on message. Sign-on can be performed only from the keyboard; it cannot be accomplished from a disk or card reader.</td>\n</tr>\n<tr>\n<td>'5</td>\n<td>EOF</td>\n<td>Pressing SF'5 sets the End of File (EOF) indicator either on or off. If the indicator is set on and an end of file condition occurs, EOF is displayed starting in Position 1 of the Send Device line to prompt the operator to service the card reader. If the indicator is set off, EOF is not displayed on the Send Device line. (SF'5 is active only if card reader was selected for a send device.)</td>\n</tr>\n<tr>\n<td>'6</td>\n<td>Print</td>\n<td>Activates the system printer for printing received print stream files. (SF'6 is active unless the emulator is configured to route all streams to disk storage.)</td>\n</tr>\n</tbody>\n</table>\n\n4.3 THE CONSOLE OUTPUT MESSAGES DISPLAY\n\nThe Console Output Messages display appears whenever the host system sends console output messages to the HASP emulation workstation. The Console Output Messages display consists of a scrolled display of console messages received from the host. Messages are listed with the most recent message last. To return to Control mode from the Console Output Messages display, press either SF'0 or RETURN. To enter Console mode from the Console Output Messages display, press SF'3.\n\n4.4 CONSOLE ENTRY AND SIGN-ON PROMPTS\n\nThe Console Entry display is activated by pressing SF'3. The Console Entry display enables console messages (such as sign-off messages) to be entered from the keyboard. If Console Entry mode is activated from Control mode, the screen is cleared and the Control Entry display appears. If Console Entry mode is activated from the Console Output Messages display, any console output messages are retained (scrolled upward) and the Console Entry display appears (refer to Figure 4-4).\n\n```\nCONSOLE ENTRY '0 ABORT\n......................1........2...........3...........4...........5...........6...........7...........8\n```\n\nFigure 4-4. Console Entry Display\nThe Sign-On display (refer to Figure 4-5) allows the entry of a sign-on message from the keyboard. It is activated by pressing SF'4.\n\n<table>\n<thead>\n<tr>\n<th>SIGNON ENTRY</th>\n<th>'0 ABORT</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>1......!..2........3........4........5........6........7........8</td>\n</tr>\n</tbody>\n</table>\n\nFigure 4-5. Sign-On Display\n\nTo send a console entry or a sign-on message from the keyboard, enter a message of 1 to 80 characters and press RETURN. Table 4-3 describes the keys that are active for cursor control during Console Entry or Sign-On mode.\n\nTable 4-3. Active Keys, Console Entry or Sign-On Entry Mode\n\n<table>\n<thead>\n<tr>\n<th>SF Key</th>\n<th>Function</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'0</td>\n<td>Restores the HASP emulator display to Control mode. No message is sent.</td>\n</tr>\n<tr>\n<td>'6</td>\n<td>Moves the cursor to Position 80.</td>\n</tr>\n<tr>\n<td>'7</td>\n<td>Moves the cursor to Position 1.</td>\n</tr>\n<tr>\n<td>'8</td>\n<td>Erases any message text between the current cursor position and Position 80.</td>\n</tr>\n<tr>\n<td>'9</td>\n<td>Deletes one character.</td>\n</tr>\n<tr>\n<td>'10</td>\n<td>Inserts one space.</td>\n</tr>\n<tr>\n<td>'11</td>\n<td>Moves the cursor five positions to the right (but not beyond Position 80).</td>\n</tr>\n<tr>\n<td>'12</td>\n<td>Moves the cursor one position to the right (but not beyond Position 80).</td>\n</tr>\n<tr>\n<td>'13</td>\n<td>Moves the cursor one position to the left (but not beyond Position 1).</td>\n</tr>\n<tr>\n<td>'14</td>\n<td>Moves the cursor five positions to the left (but not beyond Position 1).</td>\n</tr>\n<tr>\n<td>ERASE</td>\n<td>Erases any message text between Position 1 and the current cursor position.</td>\n</tr>\n<tr>\n<td>RETURN</td>\n<td>Sends a console message. Press RETURN after the message has been entered and is complete. If no data has been entered, pressing RETURN clears the Console Entry line on the HASP emulator display, and no message is sent.</td>\n</tr>\n</tbody>\n</table>\n4.5 DISK SEND OPERATIONS\n\nDisk send is initiated by pressing SF'2 from Control mode. If disk was not specified as the transmission device during the parameter selection procedure, disk send cannot be activated. Pressing SF'0 during any step of the process aborts a disk send operation and returns the HASP emulator to Control mode.\n\nWhen disk send is activated, the screen clears and a series of Disk Send prompts appears. These prompts are summarized in Table 4-4.\n\nTable 4-4. Summary of HASP Disk Send Prompts\n\n<table>\n<thead>\n<tr>\n<th>Prompt</th>\n<th>Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Send</td>\n<td>Press 1 or 2 and RETURN.</td>\n</tr>\n<tr>\n<td>1 = Normal 2 = Transparent</td>\n<td></td>\n</tr>\n<tr>\n<td>ENTER DISK ADDRESS</td>\n<td>Press the appropriate key (1-7), then press RETURN.</td>\n</tr>\n<tr>\n<td>1 = 310 2 = B10 3 = 320 4 = B20 5 = 330 6 = B30 7 = 350</td>\n<td></td>\n</tr>\n<tr>\n<td>ENTER FILE NAME</td>\n<td>Enter a valid file name and press RETURN. This prompt is repeated for up to nine files to be sent from disk. If no more files are to be transmitted, press only RETURN.</td>\n</tr>\n<tr>\n<td>LAST FILE NAMED = name</td>\n<td>The response to the previous ENTER FILE NAME prompt is displayed.</td>\n</tr>\n<tr>\n<td>RE-ENTER = name</td>\n<td>If the file name entered previously is invalid, this prompt appears.</td>\n</tr>\n<tr>\n<td>SEND FILES SEPARATELY OR COMBINED AS ONE</td>\n<td>This prompt appears if more than one send file is selected. Press RETURN to send all files as a single file. Press 1 and RETURN to send files separately.</td>\n</tr>\n<tr>\n<td>(1 = SEPARATE)?</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nThe software allows up to nine files from the same disk to be specified for disk send. Separate transmissions must be made to send files from more than one disk; repeat the disk send procedure for the files from each disk. SF'0 is also active to abort the Send mode from each of these prompts. The following prompt appears initially.\n\nSend From Disk '0 ABORT\n1=Normal 2=Transparent\nThis prompt offers a choice between Normal mode (data translated to EBCDIC before disk send) or Transparent mode (data transmitted without translation, using EBCDIC control codes). Press either 1 or 2, and then press RETURN. The following prompt then appears.\n\n```\nSend From Disk 'O ABORT\n1=310 2=B10 3=320 4=B20\n5=330 6=B30 7=350\n```\n\nEnter the single digit corresponding to the disk address for the send operation; then press RETURN. Once a valid disk address is chosen, a prompt appears showing the disk address chosen for disk send and requesting the entry of a send file name. If, for example, B20 is chosen as the disk address for disk send operations, the prompt appears as follows.\n\n```\nB20 'O ABORT\nENTER FILE NAME 01\n```\n\nEnter the name of the file to be sent and press RETURN. The software does not accept an invalid file name (a file name not cataloged on the selected disk); instead, a REENTER prompt is displayed, requesting the entry of a valid file name. For example, assume that the file name DAAT (a miscue for DATA) is entered. The software searches the specified disk catalog (in this case, B20) to find the file DAAT. If DAAT is not a valid file name, the following prompt appears to indicate that the file name is invalid and request that a valid file name be entered.\n\n```\nREENTER= DAAT 'O ABORT\nENTER FILE NAME 01\n```\n\nIf a valid file name is entered (in this case, the correct file name, DATA), the following prompt appears and a second file name can now be entered.\n\n```\nLAST FILE NAMED=DATA 'O ABORT\nENTER FILE NAME 02\n```\n\nThe software accepts up to nine files for disk send operations, and the prompt and search process is repeated for each file name. This process is terminated when RETURN is pressed instead of a file name being entered in response to the prompt ENTER FILE NAME. The software then displays the following prompt.\n\n```\nLAST FILE NAMED=DATA 'O ABORT\nSEND FILES SEPARATELY OR COMBINED AS ONE (1=SEPARATE)\n```\n\nIf RETURN is pressed, the software sends all of the specified files combined as one file. Pressing 1 in response to this prompt causes the software to send each file separately. After a valid response to this prompt is entered, the software returns to Control mode and attempts to begin transmission.\n4.6 DISK RECEIVE OPERATIONS\n\nThe HASP emulator disk receive functions are designed to sequentially fill the catalog area of the specified disk surface. If large volumes of data are expected, an alternate disk address can be assigned to accommodate disk files that overflow the primary disk. The software activates the alternate disk to receive overflow files if the primary disk catalog area becomes filled. If the free disk space of both disks is filled by received data files, no data files will be lost. The software alternately attempts to access the primary and overflow disks, displaying prompts to indicate the Disk Full condition, until free disk space is available. This feature is particularly useful if a large number of files are to be received to diskette, because filled diskettes can be replaced with unfilled indexed diskettes to continue reception operations. To accommodate multiple disk access, the following file naming convention is used.\n\nxxxxyzzz = File name\n\nWhere:\n\nxxxx = An operator-supplied file name\n\ny = An alphabetic volume designator (in alphabetic sequence beginning with \"A\")\n\nzzz = A file number (in numeric sequence 001--999)\n\nThe sequence number is automatically increased for each new file received. If more than 999 files are received to a disk surface, the volume designator is changed, and the file number is reset to 001. The volume designator is also automatically changed upon first access to the alternate disk address for overflow files.\n\nIf a received file overflows a disk surface, a partial file is written to one surface and the remainder of the file is written to the alternate surface. These two partial files are assigned the same sequence number, but the volume designator for each differs, because the volume designator changes when the emulator accesses the alternate disk surface.\n\nDisk receive operations are initiated by pressing SF'1 to activate Attention mode from the Control mode. Attention mode allows a receive file to be opened and created for data reception.\n\nNOTE\n\nTo ensure disk file integrity, the software does not open a previously written data file or a program file for disk receive operations.\nUnless the HASP emulation configuration specified no disk access (i.e., Printer was selected for the Print Streams To parameter, and None was selected for the Punch Streams To parameter), the two following disk address prompts appear in succession immediately after the emulator loading sequence.\n\n<table>\n<thead>\n<tr>\n<th>Disk Overflow surface?</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1=310 2=B10 3=320 4=B20 5=330 6=B30 7=350</td>\n</tr>\n<tr>\n<td>Disk=?_</td>\n</tr>\n</tbody>\n</table>\n\nOpen Receive Disk File\n\n<p>| |</p>\n<table>\n<thead>\n<tr>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1=310 2=B10 3=320 4=B20 5=330 6=B30 7=350</td>\n</tr>\n<tr>\n<td>Disk=?_</td>\n</tr>\n</tbody>\n</table>\n\nIn response to each of these prompts, choose a valid disk address by pressing the appropriate digit key and RETURN (e.g., press 3 and RETURN to choose disk address 320). The software does not accept an invalid disk address. Pressing RETURN without entering a digit is interpreted by the software as a decision not to assign an overflow disk surface or not to open a disk receive file at the present time. If no disk overflow surface is chosen, the disk overflow option is disabled during HASP emulator operation. For the option to be reactivated, the emulator must be restarted (by pressing HALT, RETURN, RUN, and RETURN in sequence). The Open Receive Disk File prompt, however, is accessible from the Attention mode throughout HASP emulator operation. If no receive disk file is opened at this time, a receive disk file can be opened later in the HASP session by activating Attention mode (pressing SF'1 from Control mode) and pressing SF'1.\n\nIf no sectors are available on the overflow disk or receive disk chosen, the prompt ABOVE DISK FULL - SELECT ANOTHER indicates that another disk must be chosen for receive operations.\n\nThe next prompt displays the specified disk address and the number of sectors available on the disk. For example, if Disk B10 is chosen for disk receive operations, and the disk has 192 available sectors, the prompt appears in the following form.\n\n| B10 192 SECTORS AVAILABLE |\n| ENTER 1- TO 4-CHARACTER FILE NAME? |\n\nTo create a receive file for disk receive operations, enter a file name 1 to 4 characters long, and press RETURN. The software searches the specified disk catalog to ensure that this file name has not been previously cataloged. Because the software reads only the first four characters of a file name, it does not allow a file named DATA to be opened if the specified disk contains a file or program name using DATA as its first four characters (e.g., DATAFIL).\n\nAfter a receive file name is specified, the message SEARCHING CATALOG appears, indicating that the software is searching the disk file catalog to validate the receive file name. If the software finds a data or program file name having the same first four characters as the receive file name, no receive file is opened; instead, the software displays the file name and the message CATALOGUED. REENTER. Respond by entering a different 4-character...\n\n4-10\nreceive file name. If, for example, an attempt is made to open a new file on Disk B10 (which in this case has 192 unused sectors) and DATA is chosen for a 4-character receive file name, the Attention mode display appears as in Figure 4-6.\n\n<table>\n<thead>\n<tr>\n<th>HASP Attention Mode</th>\n<th>(Communications temporarily suspended)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Receive Disk Sectors</td>\n<td>File Status</td>\n</tr>\n<tr>\n<td>Primary = B10 192</td>\n<td>DATAA001 Open</td>\n</tr>\n<tr>\n<td>Overflow = None</td>\n<td></td>\n</tr>\n<tr>\n<td>'0'=CONTROL</td>\n<td>'1'=Open RCV file</td>\n</tr>\n<tr>\n<td></td>\n<td>'2'=ERASE File</td>\n</tr>\n</tbody>\n</table>\n\nFigure 4-6. Sample Attention Mode Display\n\nPressing SF'0 returns the emulator to Control mode; the emulator is then ready to receive data files to disk. Pressing SF'2 activates the HASP Erase File function, which closes and erases an empty receive file opened by the software.\n\n4.7 CARD SEND OPERATIONS\n\nThe HASP emulator card send capabilities can be utilized if Card Reader is chosen as the input device during the configuration process. Card send can be selected from the HASP emulator display by pressing SF'2 from Control mode; the following prompt appears.\n\nInitiate Card Send\n\n'0'=Abort '1'=Normal '2'=Transparent '3'=Binary\n\nChoose the card send option appropriate for the application being run. Table 4-5 details the card send options.\n\nTable 4-5. HASP Card Send Options\n\n<table>\n<thead>\n<tr>\n<th>SF Key</th>\n<th>Send Device Message</th>\n<th>Card Send Mode</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'1'</td>\n<td>SEND NORMAL CARDS</td>\n<td>The cards are sent in EBCDIC in non-transparent mode.</td>\n</tr>\n<tr>\n<td>'2'</td>\n<td>SEND TRSP CARDS</td>\n<td>The cards are sent in EBCDIC in transparent mode. If a card containing the characters /$ in Columns 1-2 is encountered, the remaining cards are sent in binary mode.</td>\n</tr>\n<tr>\n<td>'3'</td>\n<td>SEND BINARY CARDS</td>\n<td>Data is read from the card reader in binary mode (i.e., 2 bytes per card position) and is sent in transparent mode.</td>\n</tr>\n</tbody>\n</table>\nThe Send Device message on the HASP emulator display differs according to the card send option chosen. For example, if '2' is chosen, the HASP emulator display appears as in Figure 4-7.\n\n<table>\n<thead>\n<tr>\n<th>HASP WORK STATION EMULATOR</th>\n<th>ACTIVE S.F. KEYS</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>'0'=Control '1'=ATTN '2'=Abort '3'=Console '4'=SIGNON '5'=EOF '6'=Print</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>STATUS</th>\n<th>File</th>\n<th>STREAM</th>\n<th>DEVICE</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Not Open</td>\n<td>Rcv Disk</td>\n<td>None</td>\n<td></td>\n</tr>\n<tr>\n<td>Suspended</td>\n<td>Rcv Print</td>\n<td>215</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n| EOF | Send CARD | 629 | SEND TRSP CARDS |\n\nFigure 4-7. HASP Emulator Display for Card Send\n\nOnce transmission has begun, either SF'2 or SF'5 can be used to control card reader operations.\n\n1. SF'2 aborts transmission (in the HASP emulator display, SF'2 changes from \"SEND\" to \"Abort\" — refer to Figure 4-7).\n\n2. SF'5 sets the EOF indicator on or off. If the EOF indicator is set on, EOF is displayed in Position 1 of the send device line. If the EOF indicator is set off, no EOF indicator is displayed on the send device line.\n\nThe EOF indicator is used when card data is being sent. If the indicator is set off when the card hopper empties, the HASP emulator waits for more cards before completing transmission. If the indicator is on when the hopper empties, an End of Text (ETX) signal is transmitted, thereby completing the card transmission sequence. Use SF'5 to set the EOF indicator on if only one card deck is to be sent or after the last card deck is loaded for card send.\nAPPENDIX A\nTC FILE FORMAT\n\nThe Wang 2200 Telecommunications (TC) file format for disk data files is defined as follows.\n\n1. Records are packed into a 1-dimensional array having four 62-byte elements (e.g., DIM A$(4)62). The array is saved into a single sector by using the DATA SAVE DC or DATA SAVE DA statement.\n\n2. When TC records are being packed into the array, element boundaries are ignored; the array is treated as if it were simply 248 contiguous bytes of storage.\n\n3. Within the 248 bytes of storage in a sector, three types of control bytes are used (represented by x, y, and z in the following diagram).\n\n```\n| x | y | z | Record | z | Record | z | z | Record | Unused |\n```\n\n- x = A 1-byte hexadecimal code indicating whether or not the sector is the last sector in the file; if x = HEX(F0), then x is the last sector. If x = HEX(00), then x is not the last sector.\n\n- y = A 1-byte hexadecimal value denoting the number of bytes used for data storage in the array, plus 1. For example, in the diagram, if u is the total number of bytes used in the array, then y is the hexadecimal equivalent of u + 1.\n\n- z = A 1-byte hexadecimal value preceding each record. This value denotes the record length in bytes. For example, if an individual record contains 39 bytes, z equals HEX(27), since the hexadecimal number 27 is equal to the decimal number 39.\n\nIn the diagram, \"record\" represents one complete record with trailing spaces truncated (except in the first record). Individual records do not overlap from one 248-byte array to the next (i.e., if a record is larger than the number of bytes remaining in the array, that record is written into the next sector, rather than being split between two sectors.\n\nA-1\nIn the DATA ENTRY 1 utility, the commands SAVE and SAVE N do not truncate trailing spaces in the first record of a file. Thus the first record is always 80 or 128 bytes long. The DATA ENTRY 1 utility is included in the 2200 TC Support Utilities 1 software. For more information, consult the 2200 TC Support Utilities 1 User Manual (700-4086) and its addendum (700-4086.01).\nAPPENDIX B\nMODEM CONSIDERATIONS\n\nA modem facilitates data communications by connecting computer equipment to a public telephone system or to private leased lines. Most computer equipment operates using digital signals, while most public telephone facilities provide analog signal communications lines. Therefore, a device is needed to convert a computer's digital signals into analog signals compatible with telephone lines. A modem modulates digital signals (converts them into analog signals) to enable them to be sent over analog telephone lines. For data reception, a modem demodulates analog signals (converts them into digital signals). Modems are therefore needed at both ends of a communications link. The modems at both ends of the link must be compatible with each other, to ensure that the modulation and demodulation functions performed are equivalent. The data handling speed and the methods of modulation and demodulation must be equivalent for both of the modems. The modems used should, therefore, be pairs of an identical model, or different models certified by their manufacturers to be compatible with each other.\n\nThe BSC 1 software requires that modems used for data communications be EIA RS-232-C/V.24-compatible, and capable of synchronous operations at line speeds from 2000 to 4800 bits per second (bps). Modems such as the Wang WA3451 and the Bell 212A can also be used with the BSC 1 software, even though their line speed (1200 bps synchronous) falls outside of the 2000 to 4800 bps range. These modems maintain a constant carrier signal for switched line connection, whereas the BSC 1 software normally associates a constant carrier signal with a leased line connection. If Wang WA3451 or Bell 212A modems are to be used with the BSC 1 software, the Modem Operates parameter must be set as Leased Line to accommodate this difference. Determine the type and model of modem at the remote site before installing a modem locally to further ensure modem compatibility.\n\nFor local connection of 2200 Series systems, or other Wang equipment to a 2200 system for BSC 1 operation, it might be feasible to use a Wang 2228N Null Modem rather than a pair of modems. The 2228N Null Modem can be used for local connections using RS-232-C/V.24-compatible cables, over distances of less than 50.0 feet (15.2 meters). The 2228N Null Modem allows one of the systems to supply the clocking signal and crosses the transmit and receive connections of the RS-232-C/V.24-compatible cables. The transmit pins from each system's RS-232-C/V.24-compatible cable are connected to the receive pins of the other system's cable, enabling digital signals transmitted from one system to be received by the other without modulation or demodulation. The null modem thus eliminates the need for a pair of modems and a telephone connection when the BSC 1 software is being used locally for data transfer.\nFor 2200-to-2200 protocol operations, the null modem is connected by means of the RS-232-C/V.24-compatible cable provided with each communications controller. One RS-232-C/V.24-compatible cable attaches from one of the Asynchronous/Synchronous Communications Controllers to the 2228N Null Modem. A second RS-232-C/V.24-compatible cable links the null modem to the other Asynchronous/Synchronous Communications Controller.\n\nWhen a null modem is used for local connection of a Wang OIS, WPS, or VS system to a 2200 Series system, ensure that a protocol emulator that is equivalent to one of the BSC 1 emulators is operative on the other Wang system. When a null modem is used for local connection of a non-Wang system to a 2200 Series system, ensure that the other system accepts direct connection and supports one of the protocols emulated by the BSC 1 software.\n\nFor BSC 1 operation with a null modem connecting 2200 systems, prepare an appropriate BSC 1 emulation configuration for each 2200 system. Compatible parameter selections should be chosen for the configurations. For example, data rates should be equivalent, the chosen record blocking options and the option selected for the Receive Transparency parameter (if applicable) should be the same, and the choice for the Modem Operation parameter (dial-up or leased line) should match.\n\nThe HASP Multileaving emulation cannot be operated if a null modem is used for direct connection of two systems, unless one of the systems has the BSC 1 software and the other system has a user-programmed HASP host simulator.\nAPPENDIX C\nESTABLISHING A COMMUNICATIONS CONNECTION\n\nThis manual does not include an exact procedure for establishing a communications connection, because some details vary with the type of communications equipment used. However, several aspects of the connection process should be considered here. Obtain the following information about the connection capabilities of both the local 2200 Series system and the system at the remote site.\n\n1. Are the local and remote modems compatible? As indicated in Appendix B, modems used at both ends of a communications link must be compatible. Therefore, if BSC 1 software is used to link a 2200 system to a remote system for the first time, it is necessary to determine the compatibility of the local and remote modems.\n\n2. If a dial-up connection is being used, what telephone number should be called for data transfer, and what is the appropriate dialing procedure for calling this number? (In large data centers, different telephone numbers access different remote lines. One remote line may be set up for 2780 protocol communications at a line speed of 2400 bps; another remote line may be set up for 2780 protocol at a line speed of 4800 bps; other remote lines may accept various synchronous and asynchronous communications protocols. Thus, some of the data center's telephone numbers may not be appropriate for the communications link desired. Determine the data center telephone number that is appropriate for the line discipline and line speeds to be used with the BSC 1 software and the 2200 Series system.)\n\n3. What telephone number at the remote system's facility can be called for information concerning the intended communications link or concerning problems encountered during operation of the communications link?\n\n4. What is the normal sequence of operations to be followed after a communications connection is established?\n\n a. Should the 2200 Series system transmit first? If so, is a particular sign-on message required?\n\n b. Does the remote system normally transmit first? If so, is a particular message used, and is a particular response required?\n5. What character set is used by the remote facility? (As indicated in Section 3.7, the BSC 1 software provides the capability to transmit data in EBCDIC or ASCII code, or in transparent mode. Determine which of these codes is appropriate for each application.)\n\n6. Have successful communications occurred previously? Is a currently existing configuration adequate for this particular communications link, or must a new configuration be created to suit this communications connection?\n\nOnce successful communications with a particular facility have been established, construct a step-by-step outline of the procedure to be used for subsequent sessions, including telephone numbers for the connection(s), and the names and telephone numbers of support personnel who can be contacted for assistance. This communications procedure should then be posted near the 2200 terminal used for BSC 1 communications.\nAPPENDIX D\nBSC 1 CONFIGURATION PROCEDURES SUMMARY\n\nThis appendix outlines the procedures used to create emulator configurations for the BSC 1 software. This summary should be useful as a reference both for first-time users and users more familiar with the software. It can also be used as a guideline by those writing BSC 1 configuration summaries to suit particular applications or 2200 operating systems.\n\nThe following procedures constitute an outline of the configuration process. References are provided to the sections of this manual that discuss each step in greater detail.\n\nCreating a Configuration\n\nTo create a configuration for BSC 1 software operation, perform the following steps.\n\n1. Insert the BSC 1 software diskette into a system diskette drive and use the LOAD RUN command to begin operation. (Refer to Section 1.5.)\n\n2. Select CREATE A NEW CONFIGURATION from the BSC 1 main menu. (Refer to Sections 1.6 and 2.1.)\n\n3. Select the desired emulation from the Emulator Selection menu. (Refer to Section 2.1.)\n\n4. Specify valid parameters for the chosen emulation. (Refer to Section 2.3.)\n\n5. Save or run the configuration from the Save/Run menu. (Refer to Section 2.5.)\n\nModifying a Configuration\n\nTo modify a BSC 1 software configuration, perform the following steps.\n\n1. Insert the BSC 1 software diskette into a system diskette drive and use the LOAD RUN command to begin operation. (Refer to Section 1.5.)\n2. Press RECALL (SF'15).\n\n3. Select the configuration to be modified. (Refer to Section 2.7.)\n\n4. Modify any or all parameter choices for the selected emulation. (Refer to Section 2.3.)\n\n5. Save or run the configuration from the Save/Run menu. (Refer to Section 2.5.)\n\n**NOTE**\n\nA configuration that is modified is added to the BSC 1 main menu; the original configuration is not automatically deleted.\n\n**Deleting a Configuration**\n\nTo delete a BSC 1 software configuration, perform the following steps.\n\n1. Insert the BSC 1 software diskette into a system diskette drive and use the LOAD RUN command to begin operation. (Refer to Section 1.5.)\n\n2. Position the \"#\" next to the configuration description to be deleted (using the RETURN, BACKSPACE, or Space Bar keys).\n\n3. Press DELETE (SF'9).\n\n**Deleting All Configurations**\n\nTo delete all currently saved BSC 1 software configurations, perform the following steps.\n\n1. Insert the BSC 1 software diskette into a system diskette drive and use the LOAD RUN command to begin operation. (Refer to Section 1.5.)\n\n2. Press RESET.\n\n\n4. Press RUN and RETURN. All configurations are deleted.\nAPPENDIX E\nBSC 1 OPERATION PROCEDURES SUMMARY\n\nThe following steps outline the procedure used to operate the BSC 1 software. They should prove useful for first-time users, users more familiar with the software, and those writing BSC 1 operation summaries to suit particular applications or 2200 operating systems.\n\n1. Insert the BSC 1 software diskette into a system diskette drive and use the LOAD RUN command to begin operation. (Refer to Section 1.5.)\n\n2. Load the desired configuration from the BSC 1 main menu. (Refer to Sections 1.6, 2.6, and 3.2.)\n\n3. Ready all necessary input and output devices. (Refer to Section 3.2.)\n\n4. Establish a communications connection with the remote site. (Refer to Section 3.2 and Appendix C.)\n\n5. Perform any necessary sign-on or initiation functions required by the particular application.\n\n6. Perform the desired communications functions. Chapter 3 has instructions on the various communications functions provided with the 2780, 3780, 3741, 2200-to-2200, and 2200 WPS protocols. Chapter 4 has instructions on the various communications functions provided with the HASP emulation.\n\n7. When all communications functions are completed, fulfill any sign-off or other host requirements (including disconnecting the communications line, if appropriate). Terminate the session by pressing HALT, then RETURN, then RESET.\nAPPENDIX F\nCODE TRANSLATION\n\nThe BSC 1 software accommodates two specific 8-bit transmission code sets.\n\n1. EBCDIC (Extended Binary Coded Decimal Interchange Code), with 256 assignment positions.\n\n2. USASCII (United States of America Standard Code for Information Interchange), with 128 assignment positions. (Also referred to as the ASCII code set.)\n\nThe BSC 1 code translation tables are contained in the emulator microcode modules. Wang Laboratories, Inc. does not support user access to the microcode translation tables. Tables F-1 and F-2 illustrate the EBCDIC and ASCII character sets, with hex code assignments for each character.\n\nASCII-to-EBCDIC Code Translation\n\nBefore transmission in the non-transparent mode, data is converted from ASCII to EBCDIC as follows.\n\n1. The following characters are converted to NUL (HEX 00) to avoid possible interference with data link control characters: RS (IRS), US (IUS), ETB, ETX, ENQ, SYN, DLE.\n\n2. All other ASCII control characters have EBCDIC counterparts and are converted to the equivalent EBCDIC code: ACK, SOH, STX, EOT, NAK, NUL, SUB, ESC, DEL, BEL, EM, FS (IFS), GS (IGS), SP, HS, HT, CR, LF, VT, FF, SO, SI, DC1, DC2, DC3, DC4.\n\n3. ASCII graphic characters having EBCDIC counterparts are converted to the equivalent EBCDIC code.\n a. Alphanumeric characters: A through Z, a through z, 0 through 9\n b. Punctuation symbols: . ? : ; , \" \n c. Common special graphics: # $ % & * / @ + - = ( ) _\n d. Other special graphics: <> { } \\ (grave accent) ~ (tilde) | (split vertical line)\n4. ASCII graphic characters having no EBCDIC equivalents are converted as follows.\n\n<table>\n<thead>\n<tr>\n<th>ASCII graphic</th>\n<th>EBCDIC character</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>(up arrow)</td>\n<td>¬ (logical NOT symbol)</td>\n</tr>\n<tr>\n<td>[ (left bracket)</td>\n<td>¢ (cent sign)</td>\n</tr>\n<tr>\n<td>] (right bracket)</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**EBCDIC-to-ASCII Code Translation**\n\nAfter reception in the standard mode (non-transparent), data is converted from EBCDIC to ASCII as follows.\n\n1. EBCDIC control characters having no ASCII counterparts are converted to NUL (HEX 00): PF, LC, RLF, SMM, RES, NL, IL, CC, DS, SOS, RS, BYP, SM, FS, PN, UC.\n\n2. EBCDIC characters having no control or graphic assignments are converted to NUL (HEX 00).\n\n3. EBCDIC control and graphic characters having ASCII counterparts are converted to the equivalent ASCII code. (See the characters listed under 2 and 3 in the ASCII-to-EBCDIC translation list.) The characters RS(IRS), US(IUS), ETB, ETX, ENQ, SYN, and DLE are not legal data characters and do not occur in received data.\n\n4. EBCDIC graphic characters having no ASCII counterparts are converted as follows.\n\n<table>\n<thead>\n<tr>\n<th>EBCDIC character</th>\n<th>ASCII graphic</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>¬ (logical NOT symbol)</td>\n<td>(up arrow)</td>\n</tr>\n<tr>\n<td>¢ (cent sign)</td>\n<td>[ (left bracket)</td>\n</tr>\n<tr>\n<td></td>\n<td>] (right bracket)</td>\n</tr>\n</tbody>\n</table>\n\n**NOTE**\n\nWang 2200 Series terminals and printers use the ASCII code set. Some peripherals may not display all EBCDIC or ASCII graphic characters. Furthermore, substitute graphic characters may be displayed. For details, refer to the manual that accompanies the particular peripheral.\nTable F-1. ASCII Code\n\n<table>\n<thead>\n<tr>\n<th>0</th>\n<th>1</th>\n<th>2</th>\n<th>3</th>\n<th>4</th>\n<th>5</th>\n<th>6</th>\n<th>7</th>\n<th>8</th>\n<th>9</th>\n<th>A</th>\n<th>B</th>\n<th>C</th>\n<th>D</th>\n<th>E</th>\n<th>F</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>_</td>\n<td>NUL</td>\n<td>SOH</td>\n<td>STX</td>\n<td>ETX</td>\n<td>EOT</td>\n<td>ENQ</td>\n<td>ACK</td>\n<td>BEL</td>\n<td>BS</td>\n<td>HT</td>\n<td>LF</td>\n<td>VT</td>\n<td>FF</td>\n<td>CR</td>\n<td>SO</td>\n</tr>\n<tr>\n<td>1</td>\n<td>DLE</td>\n<td>DC1</td>\n<td>DC2</td>\n<td>DC3</td>\n<td>DC4</td>\n<td>NAK</td>\n<td>SYN</td>\n<td>ETB</td>\n<td>CAN</td>\n<td>EM</td>\n<td>SUB</td>\n<td>ESC</td>\n<td>FS</td>\n<td>GS</td>\n<td>RS</td>\n</tr>\n<tr>\n<td>2</td>\n<td>sp</td>\n<td>!</td>\n<td>"</td>\n<td>#</td>\n<td>$</td>\n<td>%</td>\n<td>&</td>\n<td>'</td>\n<td>(</td>\n<td>)</td>\n<td>*</td>\n<td>+</td>\n<td>,</td>\n<td>-</td>\n<td>.</td>\n</tr>\n<tr>\n<td>3</td>\n<td>0</td>\n<td>1</td>\n<td>2</td>\n<td>3</td>\n<td>4</td>\n<td>5</td>\n<td>6</td>\n<td>7</td>\n<td>8</td>\n<td>9</td>\n<td>:</td>\n<td>;</td>\n<td><</td>\n<td>=</td>\n<td>></td>\n</tr>\n<tr>\n<td>4</td>\n<td>0</td>\n<td>A</td>\n<td>B</td>\n<td>C</td>\n<td>D</td>\n<td>E</td>\n<td>F</td>\n<td>G</td>\n<td>H</td>\n<td>I</td>\n<td>J</td>\n<td>K</td>\n<td>L</td>\n<td>M</td>\n<td>N</td>\n</tr>\n<tr>\n<td>5</td>\n<td>P</td>\n<td>Q</td>\n<td>R</td>\n<td>S</td>\n<td>T</td>\n<td>U</td>\n<td>V</td>\n<td>W</td>\n<td>X</td>\n<td>Y</td>\n<td>Z</td>\n<td>[</td>\n<td>\\</td>\n<td>]</td>\n<td>_</td>\n</tr>\n<tr>\n<td>6</td>\n<td>a</td>\n<td>b</td>\n<td>c</td>\n<td>d</td>\n<td>e</td>\n<td>f</td>\n<td>g</td>\n<td>h</td>\n<td>i</td>\n<td>j</td>\n<td>k</td>\n<td>l</td>\n<td>m</td>\n<td>n</td>\n<td>o</td>\n</tr>\n<tr>\n<td>7</td>\n<td>p</td>\n<td>q</td>\n<td>r</td>\n<td>s</td>\n<td>t</td>\n<td>u</td>\n<td>v</td>\n<td>w</td>\n<td>x</td>\n<td>y</td>\n<td>z</td>\n<td>{</td>\n<td></td>\n<td></td>\n<td>~</td>\n</tr>\n</tbody>\n</table>\n\n**NOTE**\n\nThe notation \"sp\" is used in Table F-1 to represent the space character (HEX 20).\n\n---\n\n**ASCII Control and Function Characters**\n\n- **ACK** Acknowledgment (positive)\n- **BEL** Bell (audible signal)\n- **BS** Backspace\n- **CAN** Cancel\n- **CR** Carriage Return\n- **DC1** Device Control 1 (X-ON)\n- **DC2** Device Control 2 (PN for Punch On)\n- **DC3** Device Control 3 (X-OFF)\n- **DC4** Device Control 4 (PF for Punch Off)\n- **DEL** Delete\n- **DLE** Data Link Escape\n- **EM** End of Medium\n- **ENQ** Enquiry\n- **EOT** End of Transmission\n- **ESC** Escape\n- **ETB** End of Transmission Block\n- **ETX** End of Text\n- **FF** Form Feed\n- **FS** Field or File Separator\n- **GS** Group Separator\n- **HT** Horizontal Tab\n- **LF** Line Feed\n- **NAK** Negative Acknowledgment\n- **NUL** Null\n- **RS** Record Separator\n- **SI** Shift In\n- **SO** Shift Out\n- **SOH** Start of Header\n- **STX** Start of Text\n- **SUB** Substitute\n- **SYN** Synchronous Idle\n- **US** Unit Separator\n- **VT** Vertical Tab\nTable F-2. EBCDIC Code\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>O</th>\n<th>1</th>\n<th>2</th>\n<th>3</th>\n<th>4</th>\n<th>5</th>\n<th>6</th>\n<th>7</th>\n<th>8</th>\n<th>9</th>\n<th>A</th>\n<th>B</th>\n<th>C</th>\n<th>D</th>\n<th>E</th>\n<th>F</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>NUL</td>\n<td>SOH</td>\n<td>STX</td>\n<td>ETX</td>\n<td>PF</td>\n<td>HT</td>\n<td>LC</td>\n<td>DEL</td>\n<td>RLF</td>\n<td>SM</td>\n<td>VT</td>\n<td>FF</td>\n<td>CR</td>\n<td>SO</td>\n<td>SI</td>\n<td></td>\n</tr>\n<tr>\n<td>1</td>\n<td>DLE</td>\n<td>DC1</td>\n<td>DC2</td>\n<td>DC3</td>\n<td>RES</td>\n<td>NL</td>\n<td>BS</td>\n<td>IL</td>\n<td>CAN</td>\n<td>EM</td>\n<td>CC</td>\n<td>IFS</td>\n<td>IGS</td>\n<td>IRS</td>\n<td>IUS</td>\n<td></td>\n</tr>\n<tr>\n<td>2</td>\n<td>DS</td>\n<td>SOS</td>\n<td>FS</td>\n<td>BYP</td>\n<td>LF</td>\n<td>ETB</td>\n<td>ESC</td>\n<td></td>\n<td></td>\n<td></td>\n<td>SM</td>\n<td></td>\n<td>ENQ</td>\n<td>ACK</td>\n<td>DEL</td>\n<td></td>\n</tr>\n<tr>\n<td>3</td>\n<td></td>\n<td>SYN</td>\n<td>PN</td>\n<td>RS</td>\n<td>UC</td>\n<td>EOT</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>DC4</td>\n<td>NAK</td>\n<td></td>\n<td>SUB</td>\n<td></td>\n</tr>\n<tr>\n<td>4</td>\n<td>sp</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>5</td>\n<td>&</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>6</td>\n<td>-</td>\n<td>/</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>7</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>8</td>\n<td>a</td>\n<td>b</td>\n<td>c</td>\n<td>d</td>\n<td>e</td>\n<td>f</td>\n<td>g</td>\n<td>h</td>\n<td>i</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>9</td>\n<td>j</td>\n<td>k</td>\n<td>l</td>\n<td>m</td>\n<td>n</td>\n<td>o</td>\n<td>p</td>\n<td>q</td>\n<td>r</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>A</td>\n<td>~</td>\n<td>s</td>\n<td>t</td>\n<td>u</td>\n<td>v</td>\n<td>w</td>\n<td>x</td>\n<td>y</td>\n<td>z</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>B</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C</td>\n<td>{</td>\n<td>A</td>\n<td>B</td>\n<td>C</td>\n<td>D</td>\n<td>E</td>\n<td>F</td>\n<td>G</td>\n<td>H</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>D</td>\n<td>}</td>\n<td>J</td>\n<td>K</td>\n<td>L</td>\n<td>M</td>\n<td>N</td>\n<td>O</td>\n<td>P</td>\n<td>Q</td>\n<td>R</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>E</td>\n<td>\\</td>\n<td>S</td>\n<td>T</td>\n<td>U</td>\n<td>V</td>\n<td>W</td>\n<td>X</td>\n<td>Y</td>\n<td>Z</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>F</td>\n<td>0</td>\n<td>1</td>\n<td>2</td>\n<td>3</td>\n<td>4</td>\n<td>5</td>\n<td>6</td>\n<td>7</td>\n<td>8</td>\n<td>9</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**NOTE**\n\nThe notation \"sp\" is used in Table F-2 to represent the space character (HEX 40).\n**EBCDIC Control and Function Characters**\n\n- **ACK** Acknowledgment (positive)\n- **BEL** Bell (audible signal)\n- **BS** Backspace\n- **BYP** Bypass\n- **CAN** Cancel\n- **CC** Cursor Control\n- **CR** Carriage Return\n- **DC1** Device Control 1 (X-ON)\n- **DC2** Device Control 2 (PN for Punch On)\n- **DC3** Device Control 3 (X-OFF)\n- **DC4** Device Control 4 (PF for Punch Off)\n- **DEL** Delete\n- **DLE** Data Link Escape\n- **DS** Digit Select\n- **EM** End of Medium\n- **ENQ** Enquiry\n- **EOT** End of Transmission\n- **ESC** Escape\n- **ETB** End of Transmission Block\n- **ETX** End of Text\n- **FF** Form Feed\n- **FS** Field or File Separator\n- **HT** Horizontal Tab\n- **IFS** Interchange Field Separator\n- **IGS** Interchange Group Separator\n- **IL** Idle\n- **IRS** Interchange Record Separator\n- **IUS** Information Unit Separator\n- **LC** Lowercase Shift\n- **LF** Line Feed\n- **NAK** Negative Acknowledgment\n- **NL** New Line\n- **NUL** Null\n- **PF** Punch Off\n- **PN** Punch On\n- **RES** Restore\n- **RS** Record Separator\n- **SI** Shift In\n- **SM** Set Mode\n- **SMM** Start Manual Message\n- **SO** Shift Out\n- **SOH** Start of Header\n- **SOS** Start of Significance\n- **STX** Start of Text\n- **SUB** Substitute\n- **SYN** Synchronous Idle\n- **UC** Unit Shift\n- **VT** Vertical Tab\nAPPENDIX G\nSOFTWARE PRINTER VERTICAL FORMAT CONTROL\n\nThe BSC 1 software provides several user-selectable printer vertical tape formats for the 2780, 3780, and 3741 emulations. The variable formats can be used, for example, to format received data for on-line printing on special forms. These formats can be selected for use or modified on-line (if necessary) during emulator operation. The formats can also be permanently modified off-line if necessary.\n\nNOTE\n\nThe software-controlled printer vertical tape formats are enabled only with Wang printers that use vertical format control tapes. The BSC 1 software printer vertical format option should be disregarded if such a printer is not in use.\n\nThe printer vertical tape format option can be accessed from the Attention mode display if SF'12 is pressed. If the configuration being used specifies reception to printer and disk, Lines 1 and 2 of the Attention mode display appear as follows.\n\nACTIVE KEYBOARD CONTROLS----2200 MVP BATCH EMULATOR\n'0=CONTROL '1=OPEN RCV FILE '2=ERASE FILE '12=PRT FMT TAPE\n\nIf the configuration being used specifies reception to printer only, Lines 1 and 2 of the Attention mode display appear as follows.\n\nACTIVE KEYBOARD CONTROLS----2200 MVP BATCH EMULATOR\n'0=CONTROL '12=PRT FMT TAPE '13=FF '14=VT '15=LF\n\nNOTE\n\nThe printer vertical format tape option is disabled if, during configuration, Option 2 (Printer and Disk) was chosen for the Receive To parameter, and Option 2 (via On Error) was chosen for the Disk Access Method parameter.\nPress SF'12 to access the printer vertical format tape option. The display in Figure G-1 then appears.\n\n<table>\n<thead>\n<tr>\n<th>ACTIVE KEYBOARD CONTROLS---2200 MVP BATCH EMULATOR</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0= Default printer tape 2= User format tape 2</td>\n</tr>\n<tr>\n<td>1= User format tape 1 3= User format tape 3</td>\n</tr>\n</tbody>\n</table>\n\nSee lines 6272, 6274, and 6276 for tape formats. Refer to user manual for instructions. Key 0, 1, 2, or 3 for printer format tape.\n\n<table>\n<thead>\n<tr>\n<th>MODEM SIGNALS---</th>\n<th>BLOCKS</th>\n<th>BLOCKS</th>\n<th>---MODE---</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>DTR DSR RTS CTS CAR</td>\n<td>SENT</td>\n<td>RECD</td>\n<td>ATTENTION</td>\n</tr>\n</tbody>\n</table>\n\n**Figure G-1. Vertical Printer Format Display**\n\nIf 0 is pressed, the software does not control the printer vertical tape format. (Vertical format is controlled by the vertical format tape in the printer.) If 1, 2, or 3 is pressed, however, the emulator imposes one of the three software-controlled vertical formats, overriding the printer's vertical format tape. After a valid response is entered, the emulator returns to Control mode.\n\nThe printer control tape formats are contained in Program Lines 6272, 6274, and 6276. These lines, which indicate the options for software vertical printer format control, appear as follows in a BSC 1 program listing if the LISTD command is used.\n\n```\n-6272 STR(X9$(),1)=\" A B C D E F M\"\n : RETURN\n\n-6274 STR(X9$(),1)=\" A B C D E F M\"\n : RETURN\n\n-6276 STR(X9$(),1)=\" A B C D E F M\"\n : RETURN\n```\n\n**NOTE**\n\nLine 6272 shows the format settings for Option 1. Line 6274 shows the format settings for Option 2. Line 6276 shows the format settings for Option 3. No format setting is shown for Option 0.\nIn these program lines, the placement of the format control letters (A through F, and M) represents the vertical line positions of a vertical format tape. If Option 0 is chosen for the software-controlled vertical format tape, any printer control commands that occur during data reception initiate vertical formatting controlled by the printer's vertical format tape. However, if Option 1 is chosen, any printer control commands that occur during data reception initiate vertical formatting according to the stops set in Line 6272. If the Option 1 format is used, any control code initiating a \"skip to C\" causes the printer to skip to the line represented by the C setting in the Option 1 format. Table G-1 presents the printer line skips produced by Options 1, 2, and 3. (Option 0 enables the printer's vertical format tape.)\n\nTable G-1. Vertical Printer Control Line Skips\n\n<table>\n<thead>\n<tr>\n<th>Format</th>\n<th>Printer Format Symbol</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>A</td>\n</tr>\n<tr>\n<td>1</td>\n<td>Line 5</td>\n</tr>\n<tr>\n<td>2</td>\n<td>Line 4</td>\n</tr>\n<tr>\n<td>3</td>\n<td>Line 2</td>\n</tr>\n</tbody>\n</table>\n\nThe vertical printer tape formats can be modified to accommodate user printer format requirements (for applications such as forms-filling). The formats can be modified temporarily during emulator operations, or permanently in an off-line operation.\n\nNOTE\n\nModifications to the BSC 1 software should not be performed on the BSC 1 master software diskette received from Wang Laboratories, Inc. Instead, any modifications should be performed on a backup copy. Wang Laboratories, Inc. does not support user modifications to the master software diskette. Refer to Section 1.4 for information on making backup copies of the master software diskette.\n\nIt may be necessary to examine the software printer tape formats during operation, or to modify one or more of these printer tape formats temporarily during emulator operation. In order to perform either of these activities, use the following sequence of commands to display Program Lines 6272, 6274, and 6276.\n\n1. Press HALT\n2. Press RETURN\n3. Enter LISTD 6272, 6276\n4. Press RETURN\nThese lines can now be modified by using standard BASIC-2 editing procedures. (For information on the BASIC-2 Edit mode, consult the Wang BASIC-2 Language Reference Manual, 700-4080). The positions of the printer format symbols (A through F and M) in the program lines can be changed to indicate the desired vertical printer format line skips. Note that any changes made on-line in this manner are in effect only as long as the emulator is in operation.\n\nTo return to emulator operation, press RUN, then press RETURN. The emulator returns to the Control mode display.\n\nTo permanently modify any of the printer control formats, load the appropriate BSC 1 program module (as in Step 4, following), modify the program lines, and save the modified program back onto the duplicate software diskette. There are two program modules that allow access to the printer format options.\n\n1. \"CIOVDPSS\" — This module is accessed if Option 2 (Printer and disk) was selected as the Receive To parameter during the configuration process.\n\n2. \"CIO*A10\" — This module is accessed if Option 1 (All Streams To Printer) was selected as the Receive To parameter during the configuration process.\n\nThe following steps should be followed for program module modification.\n\n1. Place a duplicate BSC 1 software diskette in an available diskette drive on the 2200 system. (Do not use the master software diskette received from Wang Laboratories, Inc. Refer to Section 1.4 for instructions on preparing a duplicate BSC 1 diskette.)\n\n2. Enter CLEAR and RETURN to clear partition memory.\n\n3. Use the SELECT statement to select the diskette drive containing the BSC 1 diskette.\n\n4. Load the appropriate BSC 1 program module.\n\n a. To modify the program module that controls printer and disk receive, enter LOAD T \"CIOVDPSS\" and press RETURN.\n\n b. To modify the program module that controls printer receive only, enter LOAD T \"CIO*A10\" and press RETURN.\n\n5. Enter LISTD 6262,6276 and press RETURN\n\n6. Modify any or all of the lines (6272, 6274, and 6276), using standard BASIC-2 editing procedures.\n7. Save the modified program module.\n\n a. To modify the program module that controls printer and disk receive, enter SCRATCH T \"CIOVDPSS\": SAVE T(\"CIOVDPSS\" and press RETURN.\n\n b. To modify the program module that controls printer receive only, enter SCRATCH T \"CIO*110\": SAVE T(\"CIO*110\" and press RETURN.\n\nThe modified program module replaces the original program module. The modifications made are selectable any time the appropriate emulation is run.\n\n---\n\nCAUTION\n\nLoad only the program module to be modified into the 2200 partition during this procedure. The BSC 1 software makes extensive use of program overlays; if another module is overlayed onto the module being modified, the modified program module may not fit back into the disk space allotted to it on the BSC 1 software diskette, and a disk error may occur. If this happens, the original module has been scratched prior to the SAVE command, and the BSC 1 diskette is no longer fully operational. For this reason, permanent modifications should only be performed off-line on a duplicate copy of the BSC 1 software (refer to Section 1.4 for instructions), and Step 2 of the modification procedure (clearing partition memory) must be performed.\nINDEX\n\nAbort .............................................. 1-8, 2-15, 3-3, 3-5, 3-8, 4-7, 4-12\nASCII Code ........................................ 2-6, 2-7, 2-9\nATOMIZE Utility ................................... 1-5\nAttention Mode, HASP ............................ 4-4, 4-9 to 4-11\nAttention Mode, 2780/3780/3741 .............. 3-2 to 3-8, 3-11 to 3-13, 3-18, 3-19\n\nBackground Operation ............................ 3-21\nBid Mode ........................................... 3-2 to 3-5, 3-7, 3-9, 3-15, 3-16, 3-18\nBinary Card Send ................................ 4-11\nBinary Synchronous Protocol .................... 1-1\n\nCard Reader ................................. 1-3, 1-4, 2-6, 2-8, 2-10, 2-12, 3-16, 3-17, 4-11, 4-12\nCard Send ........................................... 3-16, 3-17, 4-11, 4-12\nCode Translation ................................. 2-6, 2-7, 2-9, 3-9\nCombined File Send ................................. 3-15, 3-16, 4-8\nCommunications Controller ...................... 1-2, 1-3, 2-2, 2-6 to 2-13, 3-10\nConfiguration Description ...................... 1-7, 1-8, 2-15 to 2-18\nConsole Entry Mode ............................... 4-4 to 4-6\nConsole Output Mode .............................. 4-2, 4-5\nControl Mode ..................................... 3-2 to 3-20, 4-4 to 4-12\nCreate a Configuration .......................... 1-2, 1-7, 2-1, 2-2, 2-15, 2-17\n\nDATA ENTRY 1 Utility .............................. 1-5\nDE-ATOMIZE Utility ................................ 1-5\nDelete Function ................................... 3-2, 3-5, 3-8, 3-9\nDevice Status Messages .......................... 3-12 to 3-16, 4-7 to 4-11\nDisk Access Methods .............................. 1-3, 1-4, 2-8, 2-10, 2-12, 2-14, 3-6, 3-10 to 3-20\nDisk Address ..................................... 3-14 to 3-16, 4-7, 4-8\nDisk File Send ................................... 2-14, 2-15, 3-11 to 3-14, 3-18, 3-20, 4-9 to 4-11\nDisk Receive ...................................... 2-6 to 2-14, 3-7, 4-11\n\nEBCDIC Code ...................................... 2-6, 2-7, 3-3, 3-5, 3-8, 3-14, 3-15, 4-8, 4-11\nEmulator Selection Menu ......................... 1-8, 2-1\nErase File Function ............................... 3-6, 3-13, 3-14, 4-11\nError Messages ................................... 3-6, 3-7, 3-18 to 3-21, 4-3\n\nFile Send .......................................... 2-14, 3-14 to 3-16, 4-7, 4-8\n\nHASP Multileaving Protocol ...................... 1-1, 1-3, 1-4, 2-1, 2-6, 4-1 to 4-12\nHorizontal Tabbing ................................ 2-9\n\nKeyboard Entry ................................... 3-8, 3-17\nKeyboard Send ................................... 3-8, 3-17\n\nLoading a Configuration ........................ 1-3, 1-7, 2-16, 2-17, 3-1, 3-4, 3-9, 4-1\nLoading the BSC 1 Software ...................... 1-6, 1-7, 3-1, 4-1\nLocal Connection ................................ 2-2, 2-7, 2-9, 2-11, 2-13\nMain Menu .......................................................... 1-7, 1-8, 2-1, 2-15 to 2-18, 3-1\nMemory Requirements ............................................. 1-3, 1-4, 2-14\nModem Operates ...................................................... 2-7, 2-9, 2-11, 2-13\nModem Signals ....................................................... 3-8, 3-9\nModem Type .......................................................... 1-2, 2-7, 2-9, 2-11, 2-13\nModifying a Configuration ......................................... 2-17, 2-18\nMulti-Point .......................................................... 2-7, 2-9, 2-11\nMulti-Record Blocking ............................................. 2-2, 2-7, 2-9, 2-11\n\nNull Modem ......................................................... 1-2, 2-2, 2-4, 2-7, 2-9, 2-11, 2-13\n\nOn Error Method .................................................... 1-3, 1-4, 2-8 to 2-14, 3-6, 3-10 to 3-15, 3-18, 3-19\nOperational Modes .................................................. 3-2 to 3-5, 4-4\nOverflow Receive Disk ............................................. 4-9, 4-10\n\nParameter ........................................................... 1-2, 2-2 to 2-16, 2-18\nParameter Selection Menu ......................................... 2-2 to 2-5, 2-14, 2-18\nPoint-to-Point ...................................................... 2-7, 2-9\nPrint Streams ....................................................... 2-6, 2-8, 2-10, 2-12, 4-2, 4-5, 4-10\nPrinter Vertical Format Tape Control ............................ 3-6\nProtocol, 2200 to 2200 ............................................ 1-1, 1-3, 1-4, 2-13, 3-2, 3-10, 3-17, 3-20\nProtocol, 2780 ...................................................... 1-1 to 1-4, 2-2 to 2-8, 3-2, 3-10, 3-16, 3-17, 3-20\nProtocol, 3741 ...................................................... 1-1 to 1-4, 2-2, 2-3, 2-11, 2-12, 3-2, 3-16, 3-17, 3-20\nProtocol, 3780 ...................................................... 1-1 to 1-4, 2-2, 2-3, 2-9, 2-10, 3-2, 3-16, 3-17, 3-20\nPunch Streams ...................................................... 2-6, 2-8, 2-12, 4-2, 4-10\n\nRecall Function .................................................... 2-18\nRecall Key .......................................................... 2-5, 2-18\nReceive Disk File .................................................. 3-11 to 3-14, 3-18, 3-19, 4-2, 4-3, 4-9 to 4-11\nReceive File Names ................................................ 2-14, 3-11, 3-12, 3-13, 4-4\nReceive Mode ...................................................... 3-2 to 3-5, 3-9, 3-10, 3-19\nReceive To .......................................................... 2-8, 2-10, 2-12\nReceive Transparency ............................................. 2-7, 2-9\nReceived Data ........................................................ 2-6\nRecord Blocking .................................................... 2-2, 2-7, 2-9, 2-11\n\nSave/Run Menu ..................................................... 2-5, 2-14, 2-15, 2-18\nSearch Method ..................................................... 2-8 to 2-12, 2-14, 3-6, 3-10 to 3-14, 3-18, 3-19\nSend Mode .......................................................... 3-2 to 3-9, 3-14 to 3-18, 3-21, 4-4, 4-7, 4-8, 4-11, 4-12\nSign On .............................................................. 3-17, 3-18, 4-4 to 4-6\nSoftware Backup ................................................... 1-6\nSoftware Diskette .................................................. 1-1, 1-3, 1-6, 1-7, 2-1, 2-14\nSpace Compression ................................................ 2-9\nSystem Requirements .............................................. 1-2\n\nTC Board Addressing .............................................. 2-6, 2-8, 2-10, 2-12, 2-13\nTC File Format .................................................... 1-4 to 1-6, 2-6, 2-8, 2-10, 2-12, 3-10, 3-14, 3-15\nTC Support Utilities 1 Software .................................. 1-4 to 1-6\nTC/WP File Format ................................................ 3-10, 3-11\nTerminal ID .......................................................... 2-2, 2-7, 2-9, 2-11\nTransparent Send .................................................. 1-4, 2-6, 3-3, 3-5, 3-8, 3-14 to 3-17, 4-8, 4-11\nWPS Mode .......................................................... 1-1, 1-3, 1-4, 2-13, 3-2, 3-10, 3-11, 3-17, 3-20\n\nINDEX-2\nTo help us to provide you with the best manuals possible, please make your comments and suggestions concerning this publication on the form below. Then detach, fold, tape closed and mail to us. All comments and suggestions become the property of Wang Laboratories, Inc. For a reply, be sure to include your name and address. Your cooperation is appreciated.\n\nTITLE OF MANUAL: 2200 BINARY SYNCHRONOUS COMMUNICATIONS 1 (BSC 1)\nUSER GUIDE FOR 2200VP, LVP, MVP, and SVP\n\nCOMMENTS:\n\n________________________________________\nName ____________________________________ Title __________________________\n\nCompany ________________________________ Tel. # _________________________\n\nCity __________________________ State __________ Zip Code ______________"}}},{"rowIdx":74,"cells":{"id":{"kind":"string","value":"6ca7aa7951420b6afd73090342da06dfdcb7de6f"},"text":{"kind":"string","value":"**Introduction**\n\nThis guide focuses on using ARCCONF with Adaptec Smart Storage Controllers (SmartRAID/SmartHBA/SmartIOC/SmartROC). For information about using ARCCONF with Microchip Adaptec Series 8 (legacy) RAID controllers, see the *Adaptec RAID Controller Command Line Utility User’s Guide* (ESC-2160659).\n\n**Important:** All commands in this document may not be supported for your controller. Check the ARCCONF command Help section for controller specific supported commands.\nTable of Contents\n\nIntroduction.....................................................................................................................................................1\n\n1. Getting Started with the Command Line Utility...................................................................................... 4\n 1.1. Installing the Command Line Utility..................................................................................................4\n 1.2. Starting the Command Line Utility...................................................................................................4\n\n2. Using the Command Line Utility............................................................................................................ 6\n 2.1. ARCCONF Commands...................................................................................................................... 6\n 2.2. arcconf atapassword.........................................................................................................................7\n 2.3. arcconf consistencycheck................................................................................................................8\n 2.4. arcconf create..................................................................................................................................8\n 2.5. arcconf delete................................................................................................................................11\n 2.6. arcconf driverupdate......................................................................................................................11\n 2.7. arcconf expanderlist.......................................................................................................................12\n 2.8. arcconf expanderupgrade...............................................................................................................12\n 2.9. arcconf getconfig...........................................................................................................................13\n 2.10. arcconf getlogs.............................................................................................................................15\n 2.11. arcconf getsmartstats..................................................................................................................16\n 2.12. arcconf getstatus..........................................................................................................................16\n 2.13. arcconf getversion.........................................................................................................................16\n 2.14. arcconf identify.............................................................................................................................17\n 2.15. arcconf imageupdate....................................................................................................................18\n 2.16. arcconf key...................................................................................................................................18\n 2.17. arcconf list....................................................................................................................................19\n 2.18. arcconf maxcrypto.......................................................................................................................19\n 2.19. arcconf maxcryptoaccounts...........................................................................................................21\n 2.20. arcconf maxcryptokey....................................................................................................................22\n 2.21. arcconf modify.............................................................................................................................23\n 2.22. arcconf passthrough......................................................................................................................24\n 2.23. arcconf phyerrorlog.........................................................................................................................26\n 2.24. arcconf playconfig.........................................................................................................................27\n 2.25. arcconf rescan................................................................................................................................28\n 2.26. arcconf refresh................................................................................................................................28\n 2.27. arcconf romupdate........................................................................................................................29\n 2.28. arcconf saveconfig........................................................................................................................30\n 2.29. arcconf savesupportarchive.........................................................................................................30\n 2.30. arcconf setarrayparam..................................................................................................................31\n 2.31. arcconf setboot.............................................................................................................................32\n 2.32. arcconf setcache...........................................................................................................................32\n 2.33. arcconf setconfig..........................................................................................................................34\n 2.34. arcconf setconnectormode.............................................................................................................34\n 2.35. arcconf setcontrolermode.............................................................................................................35\n 2.36. arcconf setcontrollerparam..........................................................................................................36\n 2.37. arcconf setmaxcache.....................................................................................................................39\n 2.38. arcconf setname............................................................................................................................40\n 2.39. arcconf setperform.......................................................................................................................40\n\n© 2021 Microchip Technology Inc. and its subsidiaries\n1. Getting Started with the Command Line Utility\n\nThis guide explains how your Microchip Smart Storage controller supports the use of the ARCCONF command line utility. This utility allows you to:\n\n- Create and delete logical drives\n- Encrypt and decrypt logical drive data (if supported by your controller)\n- Display configuration settings\n- Copy configurations from one computer to another\n- Flash new firmware and BIOS onto the controller\n- Enable the controller to check the removal and connection of any disk drives\n- Provide access to the status and event logs of a controller\n\nNote: This guide focuses on using ARCCONF with Adaptec Smart Storage Controllers (SmartRAID/SmartHBA/SmartIOC/SmartROC). For information about using ARCCONF with Microchip Adaptec Series 8 (legacy) RAID controllers, see the Microchip Adaptec RAID Controller Command Line Utility User's Guide (ESC-2160659).\n\n1.1 Installing the Command Line Utility\n\nFollow the instructions in this section to install ARCCONF on the supported operating systems.\n\n1.1.1 Downloading the Installation Packages\n\nComplete these steps to download the ARCCONF installation package for your operating system(s):\n\n1. Open a browser window, then type start.adaptec.com in the address bar.\n2. Navigate to your controller product page, then select Storage Manager downloads.\n3. Download the ARCCONF Command Line Utility installation package.\n4. When the download completes, extract the package contents to the installation directory on your machine (Program Files or /opt, for instance).\n5. On Linux systems, ensure that arcconf has 'execute' privilege:\n chmod arcconf +x\n\n1.1.2 Installing Remote ARCCONF\n\nUse the following procedure to install Remote ARCCONF on a VMware ESXi system. Remote ARCCONF provides command line support on Windows and Linux Guest OSs.\n\n1. Copy the arcconf folder to the remote machine using the Remote Desktop Connection utility (on Windows) or a remote copy utility, such as putty or scp (on Linux).\n\n Note: You can also get remote arcconf from the maxView™ installation directory in the esx_arcconf folder.\n\n2. Run arcconf from the installation directory.\n\n1.2 Starting the Command Line Utility\n\nNote: You can run a subset of ARCCONF commands from the UEFI shell. For more information, see 3. Running ARCCONF in the UEFI Shell.\n\n1. To start ARCCONF, enter one of the following commands:\n\n<table>\n<thead>\n<tr>\n<th>Option</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Windows</td>\n<td><install_dir>\\arcconf.exe</td>\n</tr>\n<tr>\n<td>Linux</td>\n<td>/<install_dir>/arcconf</td>\n</tr>\n<tr>\n<td>Option</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-------------------------------</td>\n<td>--------------------------------------------------</td>\n</tr>\n<tr>\n<td>VMware ESXi with Remote ARCCONF</td>\n<td><code>/usr/RemoteArcconf/arcconf</code></td>\n</tr>\n</tbody>\n</table>\n\nwhere Install_dir is the directory where the utility is installed.\n\n2. To see a list of available commands, type `ARCCONF` at the prompt. For help with a specific command, type `ARCCONF <command_name> help`. \n2. Using the Command Line Utility\n\nThis chapter explains how to use the command line utility interactively or in batch mode. With interactive mode, enter commands at the prompt. In batch mode, create scripts and run the script in the appropriate shell, as described in the following table:\n\n<table>\n<thead>\n<tr>\n<th>Environment</th>\n<th>Batch File</th>\n<th>Run Script</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Windows</td>\n<td>.bat</td>\n<td>CMD.EXE</td>\n</tr>\n<tr>\n<td>Linux/Unix</td>\n<td>.sh</td>\n<td>sh / bash</td>\n</tr>\n</tbody>\n</table>\n\nIn either mode, if your command fails, you immediately see an error message of command failed. Other script messages that you can get are command completed successfully, or command aborted.\n\nThe return values for each command are the same:\n\n- **0x00**: SUCCESS\n- **0x01**: FAILURE - The requested command failed\n- **0x02**: ABORT - The command was aborted because parameters failed validation\n- **0x03**: INVALID_ARGUMENTS - The arguments are incorrect. (Displays COMMAND help)\n- **0x06**: INVALID_CARD_NUM - Unable to find the specified controller ID\n\nTo view a list of commands at the command line, type **ARCCONF** and press Enter.\n\nTo access the online help for a specific command, type **ARCCONF <command>**, then press Enter.\n\n2.1 ARCCONF Commands\n\nThe following commands are available in ARCCONF for Smart Storage controllers. The commands are described on the following pages, in alphabetical order. In the command descriptions, <> indicates a required parameter and [] indicates an optional parameter.\n\n**Attention:** ARCCONF supports commands for other controllers that are not listed in the following table. In addition, not all commands in the following table are supported by all Smart storage controllers. If you attempt to execute any command not listed in the following table, or any unsupported command for your controller, the firmware returns an error.\n### Table 2-2. ARCCONF Commands for Smart Storage Controllers\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>atapassword</td>\n<td>Sets or clears the password for SATA drives.</td>\n</tr>\n<tr>\n<td>consistencycheck</td>\n<td></td>\n</tr>\n<tr>\n<td>create</td>\n<td></td>\n</tr>\n<tr>\n<td>delete</td>\n<td></td>\n</tr>\n<tr>\n<td>driverupdate</td>\n<td></td>\n</tr>\n<tr>\n<td>expanderlist</td>\n<td></td>\n</tr>\n<tr>\n<td>expanderupgrade</td>\n<td></td>\n</tr>\n<tr>\n<td>getconfig</td>\n<td></td>\n</tr>\n<tr>\n<td>getlogs</td>\n<td></td>\n</tr>\n<tr>\n<td>getsmartstats</td>\n<td></td>\n</tr>\n<tr>\n<td>getstatus</td>\n<td></td>\n</tr>\n<tr>\n<td>getversion</td>\n<td></td>\n</tr>\n<tr>\n<td>identify</td>\n<td></td>\n</tr>\n<tr>\n<td>imageupdate</td>\n<td></td>\n</tr>\n<tr>\n<td>key</td>\n<td></td>\n</tr>\n<tr>\n<td>list</td>\n<td></td>\n</tr>\n<tr>\n<td>maxcrypto(^1)</td>\n<td></td>\n</tr>\n<tr>\n<td>maxcryptoaccounts(^1)</td>\n<td></td>\n</tr>\n<tr>\n<td>maxcryptokey(^1)</td>\n<td></td>\n</tr>\n<tr>\n<td>modify</td>\n<td></td>\n</tr>\n<tr>\n<td>passthrough(^2)</td>\n<td></td>\n</tr>\n<tr>\n<td>phyerrorlog</td>\n<td></td>\n</tr>\n<tr>\n<td>playconfig</td>\n<td></td>\n</tr>\n<tr>\n<td>rescan</td>\n<td></td>\n</tr>\n<tr>\n<td>refresh</td>\n<td></td>\n</tr>\n<tr>\n<td>romupdate</td>\n<td></td>\n</tr>\n<tr>\n<td>saveconfig</td>\n<td></td>\n</tr>\n<tr>\n<td>savesupportarchive</td>\n<td></td>\n</tr>\n<tr>\n<td>setarrayparam</td>\n<td></td>\n</tr>\n<tr>\n<td>setboot</td>\n<td></td>\n</tr>\n<tr>\n<td>setcache</td>\n<td></td>\n</tr>\n<tr>\n<td>setconfig</td>\n<td></td>\n</tr>\n<tr>\n<td>setconnectormode</td>\n<td></td>\n</tr>\n<tr>\n<td>setcontrollermode</td>\n<td></td>\n</tr>\n<tr>\n<td>setcontrollerparam</td>\n<td></td>\n</tr>\n<tr>\n<td>setmaxcache</td>\n<td></td>\n</tr>\n<tr>\n<td>setname</td>\n<td></td>\n</tr>\n<tr>\n<td>setperform</td>\n<td></td>\n</tr>\n<tr>\n<td>setpower</td>\n<td></td>\n</tr>\n<tr>\n<td>setpriority</td>\n<td></td>\n</tr>\n<tr>\n<td>setstate</td>\n<td></td>\n</tr>\n<tr>\n<td>slotconfig(^2)</td>\n<td></td>\n</tr>\n<tr>\n<td>smp</td>\n<td></td>\n</tr>\n<tr>\n<td>splitmirror</td>\n<td></td>\n</tr>\n<tr>\n<td>task</td>\n<td></td>\n</tr>\n<tr>\n<td>uninit</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**Notes:**\n\n1. Available on controllers that support maxCrypto™ Controller-Based Encryption. See the Release Notes for more information.\n\n2. Available in UEFI/ARCCONF only. See 3. Running ARCCONF in the UEFI Shell\n\n### 2.2 arccconf atapassword\n\n**Description**\nSets or clears the password for SATA drives.\n\n**Syntax**\n\n```\nARCCONF ATAPASSWORD <Controller#> [noprompt] [nologs]\nARCCONF ATAPASSWORD <Controller#> SET <new password> <Channel# ID#> [noprompt] [nologs]\nARCCONF ATAPASSWORD <Controller#> CLEAR <current password> <Channel# ID#> [noprompt] [nologs]\n```\n\n**Parameters**\n\n- **new password | current password**\n - New password, current password.\n\n- **Channel/ID**\n - Lists the space-delimited channel number and device number (ID) pairs for each drive on which to set or clear the password.\n\n**Examples**\n\n```\nARCCONF ATAPASSWORD 1 SET uR8ryx 0 1\nARCCONF ATAPASSWORD 1 CLEAR uR8ryx 0 1\n```\n2.3 arcconf consistencycheck\n\nDescription\nToggles the background consistency check modes of the controller.\n\nSyntax\n\n```\nARCCONF CONSISTENCYCHECK <Controller#> <on [Delay]|off> [nologs]\nARCCONF CONSISTENCYCHECK <Controller#> PARALLELCOUNT <Count> [nologs]\nARCCONF CONSISTENCYCHECK <Controller#> EVENTNOTIFY <Enable| Disable> [nologs]\nARCCONF CONSISTENCYCHECK <Controller#> INCONSISTENCYREPAIRPOLICY <Enable | Disable> [nologs]\n```\n\nParameters\n\n- **Controller#**\n Controller number.\n\n- **On [Delay]**\n Turns background consistency check on, with optional 0 second–30 second delay period. The delay period sets the controller idle time, after which the consistency check will start. A value of 0 disables the consistency check (effectively the same as setting the parameter to Off). If Delay is unspecified, the consistency check mode is set to HIGH. If Delay is specified, the consistency check mode is set to IDLE for the specified period.\n\n- **PARALLELCOUNT <Count>**\n Sets the parallel consistency check count. A value of 1 disables the consistency check.\n\n- **EVENTNOTIFY <Enable| Disable>**\n Sets the inconsistency event notification and serial debug message generation setting for mirrored volumes. The Enable option enables the event notification and serial debug message generation. The Disable option disables the event notification and serial debug message generation.\n\n- **INCONSISTENCYREPAIRPOLICY <Enable | Disable >**\n Sets the alternate inconsistency repair policy for RAID6 and RAID60 logical devices on the controller. The Enable option enables the inconsistency repair policy; the Disable option disables the inconsistency repair policy.\n\n- **Noprompt**\n Optional parameter that suppresses the confirmation prompt.\n\nExamples\n\n```\nARCCONF CONSISTENCYCHECK 1 OFF\nARCCONF CONSISTENCYCHECK 1 PARALLELCOUNT 4\nARCCONF CONSISTENCYCHECK 1 EVENTNOTIFY enable\nARCCONF CONSISTENCYCHECK 1 INCONSISTENCYREPAIRPOLICY enable\n```\n\n2.4 arcconf create\n\nDescription\nCreates a new encrypted or plaintext logical drive and, optionally, enables logical drive read caching, write caching. You must provide the channel and device ID of the physical devices.\n\nOn redundant logical drives, ARCCONF performs autosynchronization.\n\nNote: Do not mix SMR and PMR drives in an array.\nSyntax\n\nARCCONF CREATE <Controller#> LOGICALDRIVE [Options] <Size> <RAID#> <CHANNEL# ID#> [CHANNEL# ID#] ... [noprompt] [nologs]\nARCCONF CREATE <Controller#> LOGICALDRIVE [Options] <Size> <RAID#> ARRAY <Array#> [noprompt] [nologs]\nARCCONF CREATE <Controller#> LOGICALDRIVE ENCODE <Enable/Disable> USERROLE <userrole> [PASSWORD <password>] [Options] <Size> <RAID#> ARRAY <Array#> [noprompt] [nologs]\nARCCONF CREATE <Controller#> MAXCACHE [Options] DATALD, <LogicalDrive#> <Size> <RAID#> <CHANNEL# ID#> [Channel1# ID#]... [noprompt] [nologs]\nARCCONF CREATE <Controller#> MAXCACHE [Options] DATALD, <LogicalDrive#> <Size> <RAID#> ARRAY <maxCache Array#> [noprompt] [nologs]\nARCCONF CREATE <Controller#> RAIDZEROARRAY <Channel# ID#> [Channel# ID#]... [noprompt] [nologs]\n\nParameters\n\nController#\n\nThe controller number.\n\nLogical Drive, maxCache\n\nIndicates a logical drive or maxCache Device, with the following options:\n\n- Stripesize <STRIPE>—Allows the logical device stripe size to be built. Optional parameters for specifying a stripe size. STRIPE is specified in kilobytes 16, 32, 64, 128, 256, 512 and 1024 are supported. The default is 256 kB.\n- Legs <LEG>—Optional parameters for specifying number of legs. Value is an integer.\n - LEG—Number of legs for RAID level 50 or 60.\n - Default—2 legs\n- Name <NAME>—Optional parameter for specifying the alias name of a logical device that is displayed in the utilities. Value is a string of up to 64 characters.\n- Method <METHOD>—Initialization method for the logical drive. Valid options include: BUILD, DEFAULT.\n- LDcache—Sets the cache state for the logical device:\n - LON—cache on\n - LOFF—cache off\n- SSDIOBYPASS <enable | disable>—Specifies to enable/disable SSD I/O bypass path on an array.\n- CacheLineSize <CACHELINESIZE>—Specifies the cache line size in KB for maxCache. Adjusting the cache line size can impact maxCache performance and maximum size supported. The larger cache line size can support the larger maxCache size. The default value for this parameter is 64. Valid options can be 64, 128 and 256 based on controller support.\n- Wcache—Sets the logical drive write cache mode for maxCache devices:\n - WT—write-through (disabled)\n - WB—write-back (enabled)\n\nData Logical Drive #\n\nSpecifies the existing data logical device number to be associated with the newly created cache logical device.\n\nEncode <enable/disable>\n\nCreates encrypted or plaintext logical devices, based on the maxCrypto status and Mixed Volumes logical device properties (see notes below; see also 2.18. arconf maxcrypto):\n\n- Enable—Creates an encrypted logical device.\n- Disable—Creates a plaintext logical device.\nNote:\n1. If maxCrypto status is Disabled, only plaintext logical devices can be created.\n2. If maxCrypto status is Enabled and Mixed Volumes property is Enabled, both encrypted and plaintext logical devices can be created.\n3. If maxCrypto status is Enabled and Mixed Volumes property is Disabled, only encrypted logical devices can be created.\n4. If maxCrypto status is Enabled, then logical devices are encrypted by default.\n5. To create plaintext logical devices, the Encode option must be specified with authentication credentials (Userrole/Password).\n\nUserrole <userrole> [Password <password>]\nmaxCrypto user-role and password. Valid values are:\n- crypto (maxCrypto administrator)\n- user (standard user)\n\nArray <Array#>\nArray number on which to create the logical drive.\n\nARRAY <maxCache Array#>\nThe maxCache array number.\n\nRAIDZEROARRAY\nCreate arrays from list of physical device(s) specified.\nEach array will contain exactly one physical device and one RAID 0 logical device.\nDefault values will be applied for all logical device(s) created.\n\nSSDOverProvisioningOptimization <enable | disable>\nSpecifies to initialize solid state drives that support the rapid parity initialization feature.\n\nSize\nIndicates the size of the logical device in megabytes. Use MAX to set size to available space.\nUse MAXMBR to set the size to 2 TB.\n\nRAID#\nIndicates the RAID level for the new logical drive: 0, 1, 10, 1 Triple, 10 Triple, 50, 60, and 6 are supported.\nNote: For a complete list of supported RAID levels for your controller, refer to the product release notes.\n\nChannel# ID#\nLists the space-delimited channel number and device number pairs for each device to add to the logical device.\n\nNoprompt\nNo prompt for confirmation.\n\nExamples\n```\nARCCONF CREATE 1 LOGICALDRIVE STRIPESIZE 64 MAX 0 1 0 2 0 3 2 NOPROMPT\nARCCONF CREATE 1 LOGICALDRIVE ssdoverprovisioningoptimization enable 1024 0 ARRAY 0\n\nARCCONF CREATE 1 LOGICALDRIVE 1024 1 ARRAY 0\nARCCONF CREATE 1 LOGICALDRIVE stripesize 16 method build MAX 5 0 0 0 1 0 2\nARCCONF CREATE 1 MAXCACHE WB dataid 0 17000 1 0 0 0 1\nARCCONF CREATE 1 MAXCACHE dataid 0 17000 0 ARRAY 0\nARCCONF CREATE 1 LOGICALDRIVE ENCODE disable USERROLE crypto PASSWORD Abc@1234 MAX 5 0 0 0 1 0 2\n```\n## 2.5 arcconf delete\n\n### Description\nDeletes a logical drive, an array, or maxCache logical device. All data stored on the logical drive will be lost.\n\n### Syntax\n\n```bash\nARCCONF DELETE <Controller#> LOGICALDRIVE <LD#> [noprompt] [nologs]\nARCCONF DELETE <Controller#> LOGICALDRIVE ALL [noprompt] [nologs]\nARCCONF DELETE <Controller#> ARRAY <arr#> [noprompt] [nologs]\nARCCONF DELETE <Controller#> ARRAY ALL [noprompt] [nologs]\nARCCONF DELETE <Controller#> MAXCACHE <maxCache ld#> [noprompt] [nologs]\nARCCONF DELETE <Controller#> MAXCACHE ALL [noprompt] [nologs]\n```\n\n### Parameters\n\n- **Controller#**\n - Controller# is the controller number.\n\n- **LD#**\n - LogicalDrive# is the device number of the logical device to be deleted.\n\n- **arr#**\n - arr# is the device number of the array to be deleted.\n\n- **maxCache ld#**\n - maxCache ld# is the device number of the maxCache logical device to be deleted.\n\n- **ALL**\n - Deletes all logical devices or arrays or maxCache.\n\n- **Noprompt**\n - Optional parameter that suppresses alert messages.\n\n### Examples\n\n- `ARCCONF DELETE 1 LOGICALDRIVE 1`\n- `ARCCONF DELETE 1 ARRAY 0`\n- `ARCCONF DELETE 1 ARRAY ALL`\n\n## 2.6 arcconf driverupdate\n\n### Description\nUpdates the Windows device driver for the controller.\n\n**Note:** This command is available on Windows systems only.\n\n### Syntax\n\n```bash\nARCCONF DRIVERUPDATE <DirName> [nologs]\n```\n\n### Parameters\n\n- **DirName**\n - Absolute path to directory containing the Windows driver for the controller.\n\n- **Nologs**\n - Optional parameter that suppresses log output to the log files.\nExamples\n\n```\nARCCONF DRIVERUPDATE C:\\WINDOWS\\ALL\n```\n\n2.7 **arcconf expanderlist**\n\n**Description**\n\nReturns a list of disk drive expanders on a controller.\n\n**Syntax**\n\n```\nARCCONF EXPANDERLIST <Controller#> [nologs]\n```\n\n**Parameters**\n\n- **Controller#**\n \n Controller number.\n\n**Examples**\n\n```\nARCCONF EXPANDERLIST 1\n```\n\n2.8 **arcconf expanderupgrade**\n\n**Description**\n\nAllows new firmware to be flashed to an enclosure or expander.\n\n**Syntax:**\n\n```\nARCCONF EXPANDER UPGRADE <Controller#> ENCLOSURE <Connector# Channel# ID#> [ChunkSize#] <UpgradeType> <Filename> [Mode#] [noprompt] [nologs]\n```\n\n**Parameters**\n\n- **Controller#**\n \n Controller number.\n\n- **Channel#**\n \n Channel number of the device to be updated.\n\n- **ID#**\n \n Device number of the device to be updated.\n\n- **Connector#**\n \n Connector number of the device to be updated.\n\n- **ChunkSize#**\n \n Chunk size in bytes to be used to update the firmware. The default value is 4096 bytes.\n\n- **Filename**\n \n Name of the firmware update file.\n\n- **UpgradeType**\n\n EXPANDER—update the firmware image on the expander or enclosure.\n MFG—update the manufacturing image (BOOT SEEPROM) on the expander or enclosure.\nCPLD—update the CPLD image on the expander or enclosure.\n\n**Note:** MFG and CPLD upgrade types are supported on the Microchip Adaptec AEC-82885T expander only.\n\n### Mode#\n\nThe Mode parameter applies to EXPANDER and MFG upgrade types only. Valid values are:\n\n- **2**—download microcode only; requires system reset or power cycle to activate (default).\n- **6**—download microcode with offsets and activate.\n- **7**—download microcode with offsets, save, and activate.\n- **E**—download microcode with offsets and defer activation.\n- **F**—activate deferred microcode. It does not require the filename as an input.\n\n### Noprompt\n\nOptional parameter that suppresses alert messages.\n\n### Examples\n\n```\narcconf EXPANDERUPGRADE 1 ENCLOSURE 2 0 0 1024 EXPANDER C:\\FirmwareImage.bin 7\narcconf EXPANDERUPGRADE 1 ENCLOSURE 2 0 0 512 MFG C:\\FirmwareImage.rom 6\narcconf EXPANDERUPGRADE 1 ENCLOSURE 2 0 0 256 CPLD C:\\CPLDImage.bin noprompt\n```\n\n## 2.9 arcconf getconfig\n\n### Description\n\nLists the following information:\n\n- Array status, size and member drives\n- Controller type, status, World Wide Name (WWN), manufacturing information, and mode\n- Cache preservation status: enabled/disabled, % of cache pages preserved\n- BIOS, Boot Block, device driver, and firmware versions\n- Logical drive status, RAID level and size\n- Logical drive mount points\n- RAID 10, 50, 60 segment and group information\n- maxCache status, SSD information, and statistics of the maxCache logical drive\n- Device type, Device ID, presence of PFA\n- Physical device state, mount point (for drives with OS partition)\n- Enclosure information: fan, power supply, and temperature status\n- SGPIO virtual SEP information (virtual enclosure device for SGPIO backplanes)\n- Connectors backplane discovery protocol\n- Connector/Lane/Phy mapping\n- Green backup details\n- I2C address, clock speed, and clock stretching status\n- maxCrypto properties: status, mode, number of encrypted logical devices, master key configuration, account configuration\n- Out-of-Band interface properties\n\nAlso displays controller BIOS settings if you do not include a device-type keyword.\nNotes: When displaying adapter information (AD keyword), the Controller Status field is set to Ok or Not Ok. Its value is set to Not Ok only if:\n\n1. Communication with the controller fails. This occurs when the driver returns an error code after attempting to send a command to the controller.\n2. A logical drive was created with a newer version of arcconf. Update to the latest utilities.\n3. The controller mode (RAID/Mixed/HBA) is supported by the hardware, but not the firmware. Usually, this means that an older version of arcconf is being used against a newer controller. Update to the latest utilities.\n\nSyntax\n\n```\nARCCONF GETCONFIG <Controller#> [AD|LD [LD#]| AR[AR#]|PD [Channel# ID# Channel# ID# ...]|MC|CN| [AL]] [nologs]\n```\n\nParameters\n\nController#\n\nController number\n\nLD#\n\nDisplay information about the specified logical device\n\nAR#\n\nDisplay information about the specified array, including the associated split mirror array, if applicable\n\nAD/PD/AL...\n\n- AD—Adapter information only (including maxCrypto properties)\n- LD—Logical drive information only\n- AR—Array information only\n- PD—Physical device information only\n- MC—maxCache information only\n- CN—Connector information only\n- AL—All information\n- LD#—Optionally displays information about the specified logical device\n- AR#—Optionally displays information about the specified array\n- DEBUGTOKEN—Debug token information\n\nChannel# ID#\n\nChannel# ID#: The Channel and ID of the physical device to be display.\n\nExamples\n\n```\narcconf getconfig 1\nControllers found: 1\n-------------------------------------\nController information\n-------------------------------------\nController Status : Optimal\nController Mode : Mixed\nChannel description : SCSI\nController Model : MSCC Adaptec SmartRAID 3162-8i /e\nController Serial Number : 7139F300097\nController World Wide Name : 50000D1E001C7D80\nPhysical Slot : 6\nTemperature : 62 C/ 143 F (Normal)\nHost bus type : PCIe 3.0\nHost bus speed : 7880 Mbps\nHost bus link width : 8 bit(s)/link(s)\nPCI Address (Bus:Device:Function) : 1:0:0\nNumber of Ports : 2\nInternal Port Count : 2\nExternal Port Count : 0\nDefunct disk drive count : 0\n```\n\n© 2021 Microchip Technology Inc.\nand its subsidiaries\n### 2.10 arcconf getlogs\n\n**Description**\n\nProvides access to event logs including:\n\n- A log of special events that may have occurred (rebuilds, LDMs, and so on)\n\n**Syntax**\n\n```\nARCCONF GETLOGS <Controller#> EVENT[tabular] [nologs]\nARCCONF GETLOGS <Controller#> DEVICE <clear> <Channel# ID#> [nologs]\nARCCONF GETLOGS <Controller#> DEVICE clear ALL [nologs]\n```\n\n**Parameters**\n\n- **Controller#**\n - Controller number.\n - EVENT—controller event log\n - Clear—Clears the error counter for one or all physical drives on a controller. Clear device error counter is not applicable on 'Not Supported' drives.\n - Channel/ID—Channel and number of the physical device on the controller.\n - Tabular—Displays statistics in tabular (vs XML) format.\n\n**Examples**\n\n```\nARCCONF GETLOGS 1 EVENT tabular\nARCCONF GETLOGS 1 DEVICE clear 0 0\nARCCONF GETLOGS 1 DEVICE clear ALL\n```\n2.11 arcconf getsmartstats\n\nDescription\nDisplays SMART statistics for the hard drives and Solid State Drives (SSDs) on a controller.\n\nSyntax\nARCCONF GETSMARTSTATS <Controller#> [Tabular] [nologs]\n\nParameters\nController#\nController number.\n\nTabular\nCreates output in tabular format.\n\nExamples\nARCCONF GETSMARTSTATS 1\nARCCONF GETSMARTSTATS 1 TABULAR\n\n2.12 arcconf getstatus\n\nDescription\nThe GETSTATUS function displays the status of any background task that is currently running. The information includes the type of operation, status, logical drive number and logical drive size (for a logical device), channel ID/device ID (for a physical drive), and percentage of the operation completed.\n\nSyntax\nARCCONF GETSTATUS <Controller#> [json] [nologs]\n\nParameters\nController#\nController# is the controller number\n\njson\nDisplays the status of any background task that is currently running in JSON format.\n\nExamples\nARCCONF GETSTATUS 1 JSON\n\n2.13 arcconf getversion\n\nDescription\nLists version information for all controllers or a specific controller's software components, including information about the driver and firmware currently running.\n2.14 arcconf identify\n\nDescription\nIdentifies a physical device by blinking its LEDs. Also, identifies all the physical devices that are used to create a logical drive, maxCache or array.\n\nSyntax\nARCCONF IDENTIFY <Controller#> ALL [TIME <BlinkTime>] [STOP] [nologs]\nARCCONF IDENTIFY <Controller#> LOGICALDRIVE <LogicalDrive#> [TIME <BlinkTime>] [nologs]\nARCCONF IDENTIFY <Controller#> DEVICE <Channel# ID#> ... [TIME <BlinkTime>] [nologs]\nARCCONF IDENTIFY <Controller#> ARRAY <Array#> [TIME <BlinkTime>] [nologs]\nARCCONF IDENTIFY <Controller#> MAXCACHE [TIME <BlinkTime>] [nologs]\n\nParameters\nController#\nController number\n\nLogicalDrive#\nDevice number of the logical drive to be identified\n\nArray#\nArray number\n\nMAXCACHE\nmaxCache device to be identified\n\nChannel# ID#\nChannel number and ID number for the physical device(s) to be identified\n\nALL\nBlinks all physical devices on the controller\n\nTIME <BlinkTime>\nTime, in seconds, for the LEDs to continue blinking\n\nSTOP\nStops blinking the device\n\nExamples\nARCCONF IDENTIFY 1 DEVICE 0 0\nARCCONF IDENTIFY 1 ALL TIME 60\nARCCONF IDENTIFY 1 ALL STOP\n2.15 arcconf imageupdate\n\nDescription\nAllows new firmware to be flashed to the hard drive.\n\nSyntax:\n\n```\nARCCONF IMAGEUPDATE <Controller#> DEVICE <Channel# ID# ChunkSize# Filename> [Mode#] [BufferID#] [noprompt] [nologs]\n```\n\nParameters\n\n- **Controller**\n - Controller number.\n\n- **Channel**\n - Channel number of the device to be updated.\n\n- **ID**\n - Device number of the device to be updated.\n\n- **ChunkSize**\n - Chunk size, in bytes, to be used to update the firmware.\n \n **Note**: For SATA drives, the chunk size must be a multiple of 512.\n\n- **Filename**\n - Name of the firmware update file.\n\n- **Mode**\n - Firmware update mode. Valid values for physical drives are:\n - 7—Download microcode with offsets, save, and activate\n - 5—Download microcode in single transfer and activate\n - 14(E)—Download microcode in 'ChunkSize' byte chunks, but do not activate\n - 239(E+F)—Download microcode in 'ChunkSize' byte chunks and activate\n\n- **BufferID**\n - Mandatory for tape drive firmware update.\n\n- **Noprompt**\n - Optional parameter that suppresses alert messages.\n\nExamples\n\n```\nARCCONF IMAGEUPDATE 1 DEVICE 0 0 32768 ados.lod 3\n```\n\n2.16 arcconf key\n\nDescription\nLoads a feature key onto a controller.\n### Syntax\n\n```\nARCCONF KEY <Controller#> SET <Key#> [nologs]\n```\n\n### Parameters\n\n**Controller#**\n\nThe controller number.\n\n**Key#**\n\nThe key number provided by Microchip.\n\n### Examples\n\n```\nARCCONF KEY 1 SET ABCDEFGHIJKLMNOPQRSTUVWX\n```\n\n### 2.17 arcconf list\n\n**Description**\n\nLists all controllers in the system, or the configuration of a specific controller.\n\n**Syntax**\n\n```\nARCCONF LIST [Controller#] [nologs]\n```\n\n### Parameters\n\n**Controller#**\n\nThe controller number.\n\n### Examples\n\n```\nARCCONF LIST\nARCCONF LIST 1\n```\n\n### 2.18 arcconf maxcrypto\n\n**Description**\n\nConfigures maxCrypto settings, including:\n\n- maxCrypto master key\n- Mode (enable/disable)\n- Administrator account credentials\n- Support for mixed encrypted/plaintext volumes\n\nAlso toggles the maxCrypto mode, encodes/encrypts arrays and logical drives, and shows the maxCrypto certificate.\n\n**Syntax**\n\n```\nARCCONF MAXCRYPTO <Controller#> SETUP manual MODE <enable <ACCEPT <yes | no> > | disable>\nKEYMANAGEMENTMODE local MIXEDVOLUMES <enable | disable> MASTERKEY <masterkeystring> USERROLE\ncrypto [PASSWORD <crypto password>] [nologs]\n```\n\n```\nARCCONF MAXCRYPTO <Controller#> MODE <enable <ACCEPT <yes | no> > | disable> USERROLE <crypto | user>\n| user> [PASSWORD <crypto/user password>] [nologs]\n```\n\n```\nARCCONF MAXCRYPTO <Controller#> ENCODE LOGICALDRIVE <logicaldrive#> DATA <preserve/discard>\nUSERROLE <crypto | user> [PASSWORD <crypto/user password>] [nologs]\n```\n\n```\nARCCONF MAXCRYPTO <Controller#> ENCODE ARRAY <array#> DATA <preserve/discard> USERROLE\n```\n\n© 2021 Microchip Technology Inc.\nand its subsidiaries\nUsing the Command Line Utility\n\nParameters\n\nController#\nController number.\n\nSETUP manual\nEnables manual setup; all parameters are required.\n\nMODE <enable <ACCEPT yes | no> | disable>\nEnables creation of encrypted and plaintext logical devices and allows you to accept the maxCrypto Terms of Use. Valid values are:\n\n- Enable: Authorized users can create encrypted logical devices or plaintext logical devices, based on the value of the MIXEDVOLUMES property.\n- Disable: Authorized users can create plaintext (non-encrypted) logical devices only.\n\nKEYMANAGEMENTMODE local\nEnables local key management.\n\nMIXEDVOLUMES\nEnables mixing of encrypted and plaintext logical devices. Valid values are:\n\n- Enable: Authorized users have the option to create encrypted logical devices or plaintext logical devices.\n- Disable: New logical devices will be encrypted, with no option to create plaintext logical devices.\n\nMASTERKEY <masterkeystring>\nA 10 to 32 character string, using all printable ASCII characters.\n\nImportant: Be sure to record the master key and store in a safe place. Once set, the master key cannot be displayed or recovered, only reset.\n\nUSERROLE <userrole> [PASSWORD <password>]\nmaxCrypto user role and password. Valid values are:\n\n- crypto (maxCrypto administrator)\n- user (standard user)\n\nThe password is a 8-16 character string, comprising all printable ASCII characters. It must include at least one uppercase character, one lowercase character, one numeric, and one special character (#,!,@,...). If password is not entered on the command line, a prompt appears during command execution.\n\nENCODE\nEncrypts an existing array or logical drive, based on the maxCrypto mode and MIXEDVOLUMES property.\n\nDATA <preserve | discard>\nPreserves or discards original data in encoded logical device.\n\nSHOW certificate\n Displays the maxCrypto Terms of Use certificate.\n2.19 arcconf maxcryptoaccounts\n\nDescription\nCreates a maxCrypto standard user (non-administrator) account, sets password recovery question/answer, changes passwords, and recovers passwords.\n\nSyntax\n\narcconf maxcryptoaccounts <Controller#> CREATEUSER [CRYPTOPASSWORD <crypto password> USERPASSWORD <user password>] [nologs]\narcconf maxcryptoaccounts <Controller#> CHANGEPASSWORD USERROLE <crypto | user> [OLDPASSWORD <crypto/user password> NEWPASSWORD <crypto/user password>] [nologs]\narcconf maxcryptoaccounts <Controller#> SETRECOVERYPARAM QUESTION \"<Question>\" ANSWER \"<Answer>\" USERROLE crypto [nologs]\narcconf maxcryptoaccounts <Controller#> RECOVERPASSWORD ANSWER \"<Answer>\" USERROLE crypto [NEWPASSWORD <crypto password>][nologs]\narcconf maxcryptoaccounts <Controller#> RECOVERPASSWORD SHOW question [nologs]\n\nParameters\n\nController#\nController number.\n\nCREATEUSER\nCreates a standard user account, using the maxCrypto Administrator account (crypto).\n\nNote: The standard user account is limited to lock/unlock firmware update; see 2.36. arcconf setcontrollerparam.\n\nCRYPTOPASSWORD <crypto password>\nmaxCrypto Administrator account (crypto) password. If crypto password is not entered on the command line, a prompt appears during command execution.\n\nUSERPASSWORD <user password>\nmaxCrypto standard account (user) password. The password is a 8-16 character string, comprising all printable ASCII characters. It must include at least one uppercase character, one lowercase character, one numeric, and one special character (#,!,@,...). If user password is not entered on the command line, a prompt appears during command execution.\n\nCHANGEPASSWORD\nChanges the password for the standard user or crypto (Administrator) account.\n\nUSERROLE <crypto | user>\nThe account type: crypto (Administrator) or user (standard user).\n\nOLDPASSWORD <crypto/user password> NEWPASSWORD <crypto/user password>\nThe old password and new password for the crypto account or user account. The password is a 8-16 character string, comprising all printable ASCII characters. It must include at least one uppercase character, one lowercase character, one numeric, and one special character (#,!,@,...). If the password is not entered on the command line, a prompt appears during command execution.\n\nSETRECOVERYPARAM QUESTION \"<Question>\" ANSWER \"<Answer>\"\nSets the password recovery question and answer for the crypto (Administrator) account. The question and answer must be enclosed in quotes.\n\n**RECOVERPASSWORD ANSWER <\"Answer\"> [NEWPASSWORD <crypto password>]**\n\nAnswers the recovery question and sets the new password for the crypto (Administrator) account. If the password is not entered on the command line, a prompt appears during command execution.\n\n**RECOVERPASSWORD SHOW question**\n\nShows the recovery question.\n\n**Examples**\n\nARCCONF MAXCRYPTOACCOUNTS 1 CHANGEPASSWORD USERROLE crypto OLDPASSWORD Abc@1234 NEWPASSWORD Abc@123456\nARCCONF MAXCRYPTOACCOUNTS 1 CREATEUSER CRYPTOPASSWORD Abc@1234 USERPASSWORD Abc@123456\nARCCONF MAXCRYPTOACCOUNTS 1 SETRECOVERYPARAM QUESTION \"Which planet are you from?\" ANSWER \"i am from planet earth\" USERROLE crypto PASSWORD Abc123456\nARCCONF MAXCRYPTOACCOUNTS 1 RECOVERPASSWORD SHOW question\nARCCONF MAXCRYPTOACCOUNTS 1 RECOVERPASSWORD ANSWER \"i am from planet earth\" NEWPASSWORD Abc@123456\n\n2.20 arcconf maxcryptokey\n\n**Description**\n\nPerforms maxCrypto key management functions, including changing the master key, generating a new key for an encrypted array or logical drive, and importing a master key for a logical drive moved from another controller (allows the controller to access the encrypted data).\n\n**Syntax**\n\nARCCONF MAXCRYPTOKEY <Controller#> CHANGEMASTERKEY <masterkey> USERROLE <crypto | user> [PASSWORD <crypto/user password>][nologs]\nARCCONF MAXCRYPTOKEY <Controller#> REKEY ARRAY <array#> USERROLE <crypto | user> [PASSWORD <crypto/user password>][nologs]\nARCCONF MAXCRYPTOKEY <Controller#> REKEY LOGICALDRIVE <logicaldrive# | ALL> USERROLE <crypto | user> [PASSWORD <crypto/user password>][nologs]\nARCCONF MAXCRYPTOKEY <Controller#> IMPORT MASTERKEY <masterkey> USERROLE <crypto | user> [PASSWORD <crypto/user password>][nologs]\n\n**Parameters**\n\n**Controller#**\n\nController number.\n\n**CHANGEMASTERKEY <masterkeystring>**\n\nA 10 to 32 character string, using all printable ASCII characters.\n\n**IMPORTANT:** Be sure to record the new master key and store in a safe place. Once set, the master key cannot be displayed or recovered, only reset.\n\n**IMPORT MASTERKEY <masterkeystring>**\n\nImports the master key for a logical drive moved from another controller. The master key is a 10 to 32 character string, using all printable ASCII characters.\n\n**REKEY**\n\nGenerates a new key for an encrypted array or logical drive.\nUSERROLE <crypto | user> [PASSWORD <crypto/user password>]\n\nmaxCrypto user role: crypto (Administrator) or user (standard account), with optional password. If password is not entered on the command line, a prompt appears during command execution.\n\nExamples\n\nARCCONF MAXCRYPTOKEY 1 CHANGEMASTERKEY Abc@1234567 USERROLE crypto PASSWORD Abc@123456\nARCCONF MAXCRYPTOKEY 1 REKEY ARRAY 0 USERROLE crypto PASSWORD Abc@123456\nARCCONF MAXCRYPTOKEY 1 IMPORT MASTERKEY Abc@1234567 USERROLE crypto PASSWORD Abc@123456\n\n2.21 arccconf modify\n\nDescription\nMorphs a logical device from one RAID level to another (RAID Level Migration). Expands a logical device from original size to one with larger capacity (Online Capacity Expansion).\n\nExpands, shrinks or moves an array, or moves a logical device to a new array.\n\nNote: Do not mix SMR and PMR in an array.\n\nSyntax\n\nARCCONF MODIFY <Controller#> FROM <LogicalDrive#> TO [Options] <Size> <RAID#> <CHANNEL# ID#> [CHANNEL# ID#] ... [noprompt] [nologs]\n\nARCCONF MODIFY <Controller#> ARRAY <Array#> MOVE <Channel# ID#> [Channel# ID#] ... [nologs]\n\nARCCONF MODIFY <Controller#> ARRAY <Array#> HEAL <Channel# ID#> [Channel# ID#] ... [nologs]\n\nARCCONF MODIFY <Controller#> LOGICALDRIVE <LD#> MOVEARRAY <Array#> [nologs]\n\nARCCONF MODIFY <Controller#> LOGICALDRIVE <LD#> NEWARRAY <Channel# ID#> [Channel# ID#] ... [nologs]\n\nARCCONF MODIFY <Controller#> ARRAY <Array#> EXPAND [modifyparitygroups] <Channel# ID#> [Channel# ID#] ... [nologs]\n\nARCCONF MODIFY <Controller#> ARRAY <Array#> SHRINK [modifyparitygroups] <Channel# ID#> [Channel# ID#] ... [nologs]\n\nParameters\n\nController#\n\nThe controller number\n\nLogicalDrive#\n\nThe logical drive number to be modified\n\nArray#\n\nThe array ID of the array to be modified\n\nOptions\n\nOne of the following:\n\n- Stripsize <size>—indicates the stripe size in KB. Options are 16, 32, 64, 128, 256, 512, and 1024. The default is 256KB.\n\nSize\n\n- Size in MB.\n- MAX indicates that you want to use all available space on the disk.\n\nRAID#\n\nRAID level for the logical drive: 0, 1, 10, 50, and 60 are supported.\n\nChannel# ID#\n\nChannel number and device ID for the device\nNote: The CHANNEL# and ID# parameters are the list of devices that will contain the target modification object. Channel and ID are repeatable parameters. For RAID 1 to Simple Volume migration, CHANNEL# and ID# parameters are ignored.\n\nMOVE\nMoves an array to a new set of physical devices. Number of new physical devices must equal the number of physical devices in the original array.\n\nEXPAND\nExpands an array by adding physical device(s) to it. Only the physical device(s) that need to be added should be specified.\n\nSHRINK\nShrinks an array by removing physical device(s) from it. Only physical device(s) that need to be removed should be specified.\n\nHEAL\nReplaces failed physical devices in the array with the specified devices.\n\nMOVEARRAY\nMoves a logical device to an existing array.\n\nNEWARRAY\nMoves a logical device to a new array created with the specified physical devices.\n\nmodifyparitygroups\nReconfigures the logical device(s) parity groups based on the final number of physical devices in the array.\n\nnoprompt\nSuppresses the user prompt\n\nExamples\n\nARCCONF MODIFY 1 FROM 2 TO 2048 0 0 123 0 124 0 117\nARCCONF MODIFY 1 ARRAY 1 MOVE 0 2 0 3\nARCCONF MODIFY 1 ARRAY 1 HEAL 0 0 0 1\nARCCONF MODIFY 1 LOGICALDRIVE 0 MOVEARRAY 1\nARCCONF MODIFY 1 LOGICALDRIVE 0 NEWARRAY 0 4 0 5\nARCCONF MODIFY 1 ARRAY 1 EXPAND 0 0 0 1\nARCCONF MODIFY 1 ARRAY 1 SHRINK 0 0 0 1\nARCCONF MODIFY 1 ARRAY 1 EXPAND MODIFYPARITYGROUPS 0 0 0 1\nARCCONF MODIFY 1 ARRAY 1 SHRINK MODIFYPARITYGROUPS 0 0 0 1\n\n2.22 arcconf passthrough\n\nDescription\nSends a passthrough SCSI command. The CDB bytes are enclosed in square brackets, hex encoded, space-delimited, and must number 6, 10, 12, or 16 bytes. Read data may be redirected to a file. Write data is taken from the specified file. Transfers are limited to 2048 bytes. Transfer lengths are inferred for common SCSI CDBs but may be overridden using the length parameter.\n\nSyntax\n\nARCCONF PASSTHROUGH <Controller#> <Channel# ID#> <read|notransfer> [length] <[> CDB <]<>\n[rawhex] [noprompt] [nologs]\nARCCONF PASSTHROUGH <Controller#> <Channel# ID#> <readwithsense|notransferwithsense> [length]\n<[> <CDB<]<]> [rawhex] [noprompt] [nologs]\nARCCONF PASSTHROUGH <Controller#> <Channel# ID#> <write> [length] <[> <CDB<]<]> <Filename>\n[rawhex] [noprompt] [nologs]\nARCCONF PASSTHROUGH <Controller#> <Channel# ID#> <writewithsense> [length] <[> <CDB<]<>\n<Filename> [rawhex] [noprompt] [nologs]\n\n© 2021 Microchip Technology Inc. and its subsidiaries\nParameters\n\nCDB\nSCSI Command Descriptor Block. The CDB bytes are enclosed in square brackets, hex encoded, space-delimited, and must be 6, 10, 12, or 16 bytes.\n\nlength\nRead/write data buffer length.\n\nRead\nCommand direction is read.\n\nWrite\nCommand direction is write.\n\nnotransfer\nNo command direction (No data to read/write from/to the device).\n\nreadwithsense\nCommand direction is read with sense data.\n\nwritewithsense\nCommand direction is write with sense data.\n\nnotransferwithsense\nRead only the sense data.\n\nrawhex\nDisplays Hex data only of the Passthrough response.\n\nController#\nThe controller through which the passthrough CDB is to be sent.\n\nChannel# ID#\nThe channel and ID of the physical device.\n\nFileName\nWrite the CDB data input file.\n\nnoprompt\nSuppress alert messages.\n\nnologs\nSuppress log output.\n\nSupported Commands\nRefer to the SCSI primary/block command specification for command format for each of the following commands.\n\nTable 2-3. Passthrough CDB Commands\n\n<table>\n<thead>\n<tr>\n<th>Opcode</th>\n<th>Command</th>\n<th>Direction</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0x00</td>\n<td>TEST UNIT READY</td>\n<td>notransfer</td>\n</tr>\n<tr>\n<td>0x03</td>\n<td>REQUEST SENSE</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x08</td>\n<td>READ (6)</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x0A</td>\n<td>WRITE (6)</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x12</td>\n<td>INQUIRY</td>\n<td>read</td>\n</tr>\n<tr>\n<td>Opcode</td>\n<td>Command</td>\n<td>Direction</td>\n</tr>\n<tr>\n<td>--------</td>\n<td>------------------------------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>0x15</td>\n<td>MODE SELECT (6)</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x1A</td>\n<td>MODE SENSE (6)</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x1B</td>\n<td>START STOP UNIT</td>\n<td>notransfer</td>\n</tr>\n<tr>\n<td>0x1C</td>\n<td>RECEIVE DIAGNOSTIC RESULTS</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x1D</td>\n<td>SEND DIAGNOSTIC</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x25</td>\n<td>READ CAPACITY (10)</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x28</td>\n<td>READ (10)</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x2A</td>\n<td>WRITE (10)</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x2E</td>\n<td>WRITE AND VERIFY (10)</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x3B</td>\n<td>WRITE BUFFER</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x3C</td>\n<td>READ BUFFER</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x4C</td>\n<td>LOG SELECT</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x4D</td>\n<td>LOG SENSE</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x55</td>\n<td>MODE SELECT (10)</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x5A</td>\n<td>MODE SENSE (10)</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x5E</td>\n<td>PERSISTENT RESERVE IN</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0x5F</td>\n<td>PERSISTENT RESERVE OUT</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x85</td>\n<td>ATA PASSTHROUGH (16)</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0x88</td>\n<td>READ(16)</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0xA0</td>\n<td>REPORT LUNS</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0xA8</td>\n<td>READ (12)</td>\n<td>read</td>\n</tr>\n<tr>\n<td>0xAA</td>\n<td>WRITE (12)</td>\n<td>write</td>\n</tr>\n<tr>\n<td>0xAE</td>\n<td>WRITE AND VERIFY (12)</td>\n<td>write</td>\n</tr>\n</tbody>\n</table>\n\n### 2.23 arcconf phyerrorlog\n\n**Description**\nDisplays PHY error logs for physical devices on a controller.\n\n**Syntax**\n\n```\nARCCONF PHYERRORLOG <Controller#> DEVICE <Channel# ID#> [nologs]\nARCCONF PHYERRORLOG <Controller#> DEVICE ALL [nologs]\nARCCONF PHYERRORLOG <Controller#> ENCLOSE <Connector# Channel# ID#> EXPANDER <ExpanderID#>\nPHY <PHY#> [noprompt]\nARCCONF PHYERRORLOG <Controller#> ENCLOSE <Connector# Channel# ID#> EXPANDER <ExpanderID#> PHY ALL [noprompt]\n```\nParameters\nController#\nController number.\n\nChannel/ID\nChannel and number of the physical device on the controller.\n\nALL\nDisplays PHY error log for all physical devices.\n\nPHY#\nPHY identifier.\n\nExpander#\nExpander ID to whom the command needs to be sent.\n\nExamples\nARCCONF PHYERRORLOG 1 DEVICE 0 0\nARCCONF PHYERRORLOG 1 DEVICE ALL\nARCCONF PHYERRORLOG <Controller#> ENCLOSURE <Connector# Channel# ID#> EXPANADER <ExpanderID#>\nPHY <PHY#> [noprompt]\nARCCONF PHYERRORLOG <Controller#> ENCLOSURE <Connector# Channel# ID#> EXPANADER <ExpanderID#>\nPHY ALL [noprompt]\nARCCONF PHYERRORLOG 1 ENCLOSURE 0 2 0 EXPANADER 0 PHY 8\nARCCONF PHYERRORLOG 1 ENCLOSURE 0 2 0 EXPANADER 0 PHY ALL\n\n2.24 arcconf playconfig\n\nDescription\nConfigures a controller using a XML server template file produced by the SAVECONFIG command (see 2.28. arcconf saveconfig). Use this command to deploy the same controller configuration on multiple servers in your storage space.\n\nNotes:\n1. The XML server template file (default, saveconfig.xml) is editable. For example, you may need to change the disk drive capacity, logical drive size, or RAID level.\n2. Drives from the same vendor with slightly different capacities (147GB vs 150GB, for instance) are considered interchangeable. If the interchange results in a change in logical drive capacity, the drive is scaled, as needed. For example, if the new drives have 4% more capacity due to vendor or model changes, then all logical drives are increased in size by 4%.\n3. Be sure to check the log file to verify that the controller was configured successfully. The exit codes, shown in the following table, indicate the success or failure of the operation and if the system needs to be rebooted.\n\n<table>\n<thead>\n<tr>\n<th>Code</th>\n<th>Value</th>\n<th>Meaning</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SUCCESS</td>\n<td>0</td>\n<td>Configuration succeeded, no reboot is required.</td>\n</tr>\n<tr>\n<td>FAILURE_GENERAL</td>\n<td>1</td>\n<td>An error occurred and the configuration could not be completed.</td>\n</tr>\n<tr>\n<td>SUCCESS_REBOOT</td>\n<td>2</td>\n<td>Configuration succeeded, but a reboot is required.</td>\n</tr>\n</tbody>\n</table>\n\nSyntax\nARCCONF PLAYCONFIG <Input XML File> [LogFile] [FORCE ALL|LOGICALSIZE] [SLOTID][nologs]\nThe pathname of the server template file. The default server template file is available at C:\\PMCS\\Logs\\saveconfig.xml.\n\nLogFile\n\nSets the pathname of the error log file. By default, the error log is available at C:\\PMCS\\Logs\\playconfig.log.\n\nFORCE\n\nForces deployment of the server even if the controller does not support all features, or the drive capacity does not match the configuration in the input XML file. Use FORCE ALL to force deployment of all features; use FORCE LOGICALSIZE to force deployment of just the logical drives.\n\nSLOTID\n\nApply the configuration based on Slot ID instead of Device ID.\n\nExamples\n\nARCCONF PLAYCONFIG server1_config.xml playconfig.log FORCE ALL\n\n2.25 arcconf rescan\n\nDescription\n\nEnables the controller to check for the removal of any disk drives and to check for the connection of any new disk drives to the controller. Controller rescan runs in the background, asynchronously. When rescan is started, a message is displayed stating that the process is running in the background and may take 10 minutes to complete. Another message is displayed if a rescan is started while one is already in progress.\n\nSyntax\n\nARCCONF RESCAN <Controller#> [nologs]\nARCCONF RESCAN ALL [nologs]\n\nParameters\n\nController#\n\nThe controller number\n\nALL\n\nRescans all controllers in the system\n\nExamples\n\nARCCONF RESCAN 1\nARCCONF RESCAN ALL\n\n2.26 arcconf refresh\n\nDescription\n\nRefresh the security status of Self Encryption Drive (SED).\n\nSyntax\n\nARCCONF REFRESH <Controller#> SEDSECURITYSTATUS <LockedOnly|ALL> [nologs]\nARCCONF REFRESH <Controller#> SEDSECURITYSTATUS DEVICE <Channel# ID#> [nologs]\nParameters\n\nController# \nThe controller number\n\nSEDSECURITYSTATUS \nSED security status\n\nLockedOnly \nOption to refresh the security status of locked SED drives.\n\nALL \nOption to refresh the security status of all SED drives.\n\nChannel# ID# \nThe Channel and ID of the SED physical device.\n\nExamples\n\nARCCONF REFRESH 1 SEDSECURITYSTATUS LockedOnly\nARCCONF REFRESH 1 SEDSECURITYSTATUS Device 0 5\n\n2.27 \narcconf romupdate\n\nDescription\n\nAllows new firmware and BIOS to be flashed to the controller. A reboot is required for the new firmware to take effect.\n\nNote:\n\n1. This command is supported on all OSs that support maxView Storage Manager.\n\nSyntax\n\nARCCONF ROMUPDATE <Controller#> <ImagePath> [once] [noprompt] [nologs]\nARCCONF ROMUPDATE 1 toggle [noprompt] [nologs]\n\nParameters\n\nController# \nThe controller number.\n\nImagePath \nThis is the full path of the ROM image file.\n\ntoggle \nToggles active ROM image to backup ROM image.\n\nonce* \nIf specified, only the active ROM is flashed with the new image.\n\nNote:\n\nWhen updating the controller firmware, it is recommended not to add this parameter so that both the active and backup ROM images will be flashed.\n\nNoprompt \nAn optional parameter that suppresses the confirmation prompt.\n\nExamples\n\nARCCONF ROMUPDATE 1 C:\\firmwareImage\\SmartFW.bin noprompt\nARCCONF ROMUPDATE 1 toggle\nARCCONF ROMUPDATE 1 C:\\firmwareImage\\SmartFW.bin once\n2.28 arcconf saveconfig\n\nDescription\nThis command is supported on all OSs that support arcconf/maxView Storage Manager.\n\nSaves the controller configuration to a XML server template file, including the controller type, operational settings, physical drive size, logical drive size, RAID level, and more. Use this file with the PLAYCONFIG command to deploy the same controller configuration to other servers in your storage space; see 2.24. arcconf playconfig for more information.\n\nNote: Be sure to check the log file to verify that the configuration XML file was created successfully. The exit codes, shown in the following table, indicate the success or failure of the operation.\n\n<table>\n<thead>\n<tr>\n<th>Code</th>\n<th>Value</th>\n<th>Meaning</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SUCCESS</td>\n<td>0</td>\n<td>Configuration XML generated successfully.</td>\n</tr>\n<tr>\n<td>FAILURE_GENERAL</td>\n<td>1</td>\n<td>An error occurred and the configuration XML could not be generated.</td>\n</tr>\n</tbody>\n</table>\n\nSyntax\nARCCONF SAVECONFIG [Input XML File] [LogFile] [nologs]\n\nParameters\nInput XML File\nThe pathname of the server template file. The default name (if you omit this parameter) is C:\\PMCS\\Logs\\saveconfig.xml.\n\nLogFile\nThe pathname of the error log file. By default, the error log is available at C:\\PMCS\\Logs\\saveconfig.log.\n\nExamples\nARCCONF SAVECONFIG server1_config.xml C:\\LOGS\\SERVER1.LOG\n\n2.29 arcconf savesupportarchive\n\nDescription\nSaves configuration and status information to help diagnose a problem with your system. Saved information includes device logs, drive logs, event logs, error logs, controller logs, history logs, basecode logs, and SMART statistics.\n\nBy default, the log files are saved in the Support folder in the standard logs directory for your operating system (/var/log for Linux, and so on).\n\nSyntax\nARCCONF SAVESUPPORTARCHIVE [Path] [Firmware|Arcconf|Storlib|Basecode|GUI|Redfish] [Firmware Uartlog|Diagnostics] [nologs]\n\nParameters\nPath\nPath to store the log files.\n\nLog type:\nOne of these options:\n\n- **Firmware**: saves Firmware logs\n- **Type**\n - **Uartlog**: saves controller serial logs\n - **Diagnostics**: saves controller debug logs\n- **Arcconf**: saves Arcconf logs\n- **Storlib**: saves StorLib logs\n- **Basecode**: saves basecode logs\n- **GUI**: saves GUI logs\n- **Redfish**: saves Redfish logs\n\n**Examples**\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ARCCONF SAVESUPPORTARCHIVE</td>\n</tr>\n<tr>\n<td>ARCCONF SAVESUPPORTARCHIVE Firmware</td>\n</tr>\n<tr>\n<td>ARCCONF SAVESUPPORTARCHIVE C:\\Adaptec\\maxView Firmware</td>\n</tr>\n<tr>\n<td>ARCCONF SAVESUPPORTARCHIVE firmware diagnostics</td>\n</tr>\n</tbody>\n</table>\n\n### 2.30 **arcconf setarrayparam**\n\n**Description**\nChanges a parameter of an array.\n\n**Syntax**\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ARCCONF SETARRAYPARAM <Controller#> <Array#> SPARETYPE <Type> [noprompt] [nologs]</td>\n</tr>\n<tr>\n<td>ARCCONF SETARRAYPARAM <Controller#> <Array#> CONSOLIDATESPACE [noprompt] [nologs]</td>\n</tr>\n<tr>\n<td>ARCCONF SETARRAYPARAM <Controller#> <Array#> SSDIOBYPASS <enable/disable> [nologs]</td>\n</tr>\n</tbody>\n</table>\n\n**Parameters**\n\n- **Controller#**\n - Controller number\n\n- **Array#**\n - Array number to be modified\n\n- **SPARETYPE**\n - Sets the spare type for the array:\n - 1—Dedicated—A spare that replaces a failed drive in the array, and is shareable between arrays.\n - 2—Autoreplace—A spare that replaces a failed drive in the array, and is not sharable between arrays.\n\n- **SSDIOBYPASS**\n - Enables or disables I/O bypass for all logical devices in the array. Default is enabled.\n - Enable—I/O bypass on array will be enabled.\n - Disable—I/O bypass on array will be disabled.\n\n**Examples**\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ARCCONF SETARRAYPARAM 1 0 SPARETYPE 1</td>\n</tr>\n<tr>\n<td>ARCCONF SETARRAYPARAM 1 0 SSDIOBYPASS enable</td>\n</tr>\n</tbody>\n</table>\n2.31 arcconf setboot\n\nDescription\nSets the controller as a boot device for the system. This command is available only when the controller is offline.\n\nSyntax\n```\nARCCONF SETBOOT <Controller#> LOGICALDRIVE <LogicalDrive#> [TYPE <Boot Type>] [noprompt] [nologs]\nARCCONF SETBOOT <Controller#> DEVICE <Channel# ID#> TYPE <Boot Type> [nologs]\n```\n\nParameters\n- Controller#\n - Controller number\n- LogicalDrive#\n - Logical drive number to mark as the boot device\n- Channel# ID#\n - Channel and ID of the physical device to mark as the boot device.\n- TYPE <Boot Type>\n - Boot type of the logical or physical device:\n - Primary—Primary boot logical/physical device\n - Secondary—Secondary boot logical/physical device\n - All—Primary and secondary boot logical/physical device.\n - None—Non-bootable\n\nExamples\n```\nARCCONF SETBOOT 1 LOGICALDRIVE 0 TYPE primary\nARCCONF SETBOOT 1 DEVICE 0 5 TYPE secondary\n```\n\n2.32 arcconf setcache\n\nDescription\nChanges the cache mode for a logical drive, or the write cache mode for all drives or a single physical drive on a controller.\n\nSyntax\n```\nARCCONF SETCACHE <Controller#> LOGICALDRIVE <LogicalDrive#> | All <logical mode> [noprompt] [nologs]\nARCCONF SETCACHE <Controller#> DRIVESTORECACHEPOLICY <DriveType> <CachePolicy> [noprompt] [nologs]\nARCCONF SETCACHE <Controller#> CACHERATIO <read#> <write#> [nologs]\nARCCONF SETCACHE <Controller#> WRAITECACHEBYPASSTHRESHOLD <threshold size> [nologs]\nARCCONF SETCACHE <Controller#> NOBATTERYWRITECACHE <enable | disable> [nologs]\nARCCONF SETCACHE <Controller#> RECOVERCACHEMODULE [nologs]\n```\n\nParameters\n- Controller#\n - The controller number\n- LogicalDrive#\n - Logical drive number to mark as the boot device\nThe number of the logical drive whose cache will be altered\n\nLogical mode\nLogical drive cache mode:\n• con—cache enabled\n• coff—cache disabled\n\nChannel/ID\nLists the space-delimited channel number and device number pairs for each device.\n\nDRIVETYPE\n• Configured—drive write cache policy for configured drives\n• Unconfigured—drive write cache policy for unconfigured drives\n• HBA—drive write cache policy for HBA drives\n\nCachePolicy\nWrite cache policy setting; choose any of the following values\n• 0—default\n• 1—enable\n• 2—disable\n• 3—Unchanged\n\nNote: “Unchanged” write cache policy is only applicable for configured drives.\n\nCACHERATIO <read#> <write#>\nSets the cache ratio for the controller:\n• read#—read cache percentage\n• write#—write cache percentage\n\nNote: Some controllers support 8 GB DDR but only 4 GB can be backed up by the backup power source. In such scenario, write cache ratio can be configured to a maximum of 50 percent.\n\nWAITFORCACHEROOM\nWait for room in the read/write cache when full instead of automatically bypassing it in favor of higher performance. Enabling this feature prevents RAID 1 inconsistencies that occur whenever the host changes buffer contents during write operations.\n• Enable—wait for room in the read/write cache\n• Disable—do not wait for room in the read/write cache\n\nNOBATTERYWRITECACHE\nEnables write caching when a battery or supercapacitor is not present or fully charged. This setting applies to all logical drives on the controller; at least one logical drive must exist before usage.\n• Enable—enable write caching on controller without fully charged battery or supercapacitor\n• Disable—disable write caching on controller without fully charged battery or supercapacitor\n\nCAUTION\nEnabling write caching without a fully charged battery/supercapacitor may cause data loss in the event of a power failure.\n\nWRITECACHEBYPASSTHRESHOLD\nSets the write cache bypass threshold for the controller. This allows you to choose a value to bypass the cache when the large write reaches that threshold. Units are in KB and the value must be a multiple of 16 KB. The target can be any valid controller.\n• Threshold size—the valid threshold size is between 16 KB and 1040 KB.\nRECOVERCACHEMODULE\n\nRecovers the failed cache module.\n\nExamples\n\nARCCONF SETCACHE 1 CACHERATIO 60 40\nARCCONF SETCACHE 1 WAITFORCACHEROOM enable\nARCCONF SETCACHE 1 NOBATTERYWRITECACHE enable\nARCCONF SETCACHE 1 DRIVEWRITECACHEPOLICY Configured 0 Unconfigured 1 hba 2\nARCCONF SETCACHE 1 WRITECACHEBYPASTHRESHOLD 1040\nARCCONF SETCACHE 1 RECOVERCACHEMODULE\n\n2.33 arcconf setconfig\n\nDescription\n\nResets the controller configuration. Logical drives are deleted, hard disks are reset to the READY state, cache contents are lost, and controller settings are reset to default values. Optionally, you can clear the maxCrypto configuration, including all keys, passwords, and maxCrypto users (administrator and standard user).\n\nSyntax\n\nSETCONFIG <Controller#> [DEFAULT | CLEARMAXCRYPTOCONFIG] [noprompt] [nologs]\n\nParameters\n\nController#\n\nThe controller number.\n\nDefault\n\nRestores the controller's default configuration.\n\nClearmaxcryptoconfig\n\nRestores the default maxCrypto configuration.\n\nNoprompt\n\nNo prompt for confirmation.\n\nExamples\n\nARCCONF SETCONFIG 1 DEFAULT\nARCCONF SETCONFIG 1 CLEARMAXCRYPTOCONFIG\n\n2.34 arcconf setconnectormode\n\nDescription\n\nUse this command to configure controller connectors to different operating modes:\n\n- **HBA Mode**—Allows the connector to act and be used as a Host Bus Adapter. RAID functions of the controller are disabled. All attached drives are surfaced as RAW devices.\n- **RAID: Hide RAW**—All RAID functions of the controller are enabled for the connector, but RAW devices are not exposed to the operating system.\n- **Mixed**—RAID volumes and RAW drives on the connector are exposed to operating system.\nSyntax:\nARCCONF SETCONNECTORMODE <Controller#> <Connector #> <Functional Mode#> <Connector #> <Functional Mode#> ... [noprompt] [nologs]\n\nParameters\nController#\nController number.\n\nConnector#\nConnector number.\n\nFunctional Mode#\nOne of the following values:\n- 1—HBA Mode\n- 2—RAID: Hide RAW\n- 3—Mixed\n\nnologs\nSuppresses log output.\n\nExamples\nARCCONF SETCONNECTORMODE 1 1 1\nARCCONF SETCONNECTORMODE 1 3 3\n\n2.35 arcconf setcontrollermode\n\nDescription\nUse this command to configure the controller operating mode for all connectors:\n- HBA Mode—Allows the controller to act and be used as a Host Bus Adapter. RAID functions of the controller are disabled. All attached drives are surfaced as RAW devices.\n- RAID: Hide RAW—All RAID functions of the controller are enabled, but RAW devices are not exposed to the operating system.\n- Mixed—RAID volumes and RAW drives are exposed to operating system.\n\nSyntax\nARCCONF SETCONTROLLERMODE <Controller#> <Controller Mode> [nologs]\n\nParameters\nController Mode\nChange a controller's mode.\n- 2—HBA Mode\n- 3—RAID: Hide RAW\n- 5—Mixed\n\nExamples\nARCCONF SETCONTROLLERMODE 1 2\n## 2.36 arcconf setcontrollerparam\n\n**Description** \nChanges a parameter of a controller.\n\n**Syntax**\n\n```\nARCCONF SETCONTROLLERPARAM <Controller#> QUEUEDEPTH <QDepth> [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> SPAREACTIVATIONMODE <Mode> [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> ELEVATORSORT <Enable | Disable> [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> LATENCY <Latency> [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> SANITIZELOCK <sanitizeLock> [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> MIXEDVOLUMES <Enable | Disable> USERROLE <userrole> \nARCCONF SETCONTROLLERPARAM <Controller#> FWLOCK <Enable | Disable> USERROLE <userrole> \nARCCONF SETCONTROLLERPARAM <Controller#> PASSWORD <password> [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> DISCOVERYPROTOCOL <All discoveryProtocol> [noprompt] [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> DISCOVERYPROTOCOL <Connector# discoveryProtocol> [noprompt] [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> DISCOVERYPROTOCOL <All DirectAttachedCable NUMBEROFTARGETS NumberOfTargets#> [noprompt] [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> DISCOVERYPROTOCOL <Connector# DirectAttachedCable NUMBEROFTARGETS NumberOfTargets#> [Connector# DirectAttachedCable NUMBEROFTARGETS]... [noprompt] [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> OOBINTERFACE <OOBinterface> [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> OOBINTERFACE PBSI I2CADDRESS <i2cAddress> I2CCLOCKSTRETCH <i2cClockStretch> [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> OOBINTERFACE MCTP I2CADDRESS <i2cAddress> SMBUSDEVICETYPE <SMBusDeviceType> SMBUSCHANNEL <SMBusChannel> STATICEID <StaticEID> VDMNOTIFICATION <VDMNotification> [nologs] \nARCCONF SETCONTROLLERPARAM <Controller#> EXPANDERSCANDURATION <duration> [nologs]\n```\n\n**Parameters**\n\n- **Controller#** \n Controller number\n\n- **QUEUEDEPTH <QDepth>** \n Sets the queue depth for the controller. Valid values are 0, 2, 4, 8, 16, and 32. A value of 0 indicates automatic queue depth.\n\n- **SPAREACTIVATIONMODE <mode>** \n Sets the spare activation mode from activation on failure to predictive spare activation. Valid values are:\n - 0—Activate on failure (default)\n - 1—Activate on predictive failure\n\n- **ELEVATORSORT** \n Sets the behavior of the controller cache write Elevator sort algorithm.\n\n- **LATENCY** \n Sets the flexible latency scheduler. Valid values are:\n - 0—Disable (default).\n - 1—Low. Sets value to 250.\n - 2—Medium. Sets value to 100.\n• 3—High. Sets value to 50.\n• 4—Aggressive level 1. Sets value to 30.\n• 5—Aggressive level 2. Sets value to 10.\n\nSANITIZELOCK\nSets the Sanitize lock on the controller.\n\n• sanitizeLock\n – None—Default setting\n – Freeze—Freezes the Sanitize operation on all supported drives\n – AntiFreeze—Blocks setting the Freeze mode on all supported drives. Prevents further attempts to freeze the Sanitize operation on the hard drive.\n\nMIXEDVOLUMES\nEnables mixing of encrypted and plaintext logical devices. Valid values are:\n\n• Enable—Authorized users have the option to create encrypted logical devices or plaintext logical devices (not encrypted).\n• Disable—New logical devices will be encrypted, with no option to create plaintext logical devices.\n\nFWLOCK\nLocks/unlocks controller firmware update. Valid values are:\n\n• Enable—Authorized users can update the controller firmware.\n• Disable—Controller firmware cannot be updated.\n\nUSERROLE <userrole> PASSWORD <password>\nMaxCrypto user-role and password. Valid values are:\n\n• crypto (maxCrypto administrator)\n• user (standard user)\n\nOOBINTERFACE\nSets the Out-of-band interface settings for the controller. Parameters for configuring OOB interface:\n\n• PBSI\n• MCTP\n\nPBSI\nSets the Out-of-band interface as PBSI.\n\n<table>\n<thead>\n<tr>\n<th>PBSI Parameters</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>I2CADDRESS</td>\n<td>Sets the I2C Address of the controller. Hexadecimal input from range of 0x00—0xFF</td>\n</tr>\n</tbody>\n</table>\n| i2cClockSpeed | Sets I2C clock speed\n • 1—I2C clock speed 10 kHz\n • 2—I2C clock speed 100 kHz\n • 3—I2C clock speed 400 kHz\n • 4—I2C clock speed 800 kHz |\n| i2cClockStretch | Sets the I2C clock stretch\n • Enable—Enables I2C Clock Stretching\n • Disable—Disables I2C Clock Stretching |\n\nMCTP\nSets the Out-of-band interface as MCTP.\n## MCTP parameters\n\n<table>\n<thead>\n<tr>\n<th>MCTP parameters</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>I2CADDRESS</td>\n<td>Sets the I2C address of the controller. Hexadecimal input. For valid range, refer to the Management Component Transport Protocol (MCTP) SMBus/I2C Transport Binding Specification document.</td>\n</tr>\n<tr>\n<td>SMBusDeviceType</td>\n<td>Sets System Management(SM) Bus Device Type</td>\n</tr>\n<tr>\n<td></td>\n<td>• 0—Default</td>\n</tr>\n<tr>\n<td></td>\n<td>• 1—Fixed: Fixed and not discoverable. If this value is set, the I2C address is fixed and will not be able to be assigned with ARP.</td>\n</tr>\n<tr>\n<td></td>\n<td>• 2—Address Resolution Protocol (ARP) capable Bus master can assign the I2C address dynamically to slave devices to resolve the address conflicts.</td>\n</tr>\n<tr>\n<td>SMBusChannel</td>\n<td>Sets the System Management(SM) Bus Channel setting</td>\n</tr>\n<tr>\n<td></td>\n<td>• Enable—Enables SM Bus Channel</td>\n</tr>\n<tr>\n<td></td>\n<td>• Disable—Disables SM Bus Channel</td>\n</tr>\n<tr>\n<td>StaticEID</td>\n<td>Sets the Static End Point Identifier (EID) Setting</td>\n</tr>\n<tr>\n<td></td>\n<td>• Enable—Enables Static EID</td>\n</tr>\n<tr>\n<td></td>\n<td>• Disable—Firmware passes EID as 0 (internally) and the bus owner assigns the EID.</td>\n</tr>\n<tr>\n<td>VDMNotification</td>\n<td>Sets the Vendor Defined Message (VDM) discovery notification</td>\n</tr>\n<tr>\n<td></td>\n<td>• Enable—Enabling VDM Discovery Notify supports sending discovery notification during a PCI bus re-enumeration. This message is available for use as a common message for enabling an endpoint to announce its presence to the bus owner. This is typically used as a part of the endpoint discovery process when an MCTP device is hot-plugged onto or becomes powered-up on an MCTP bus.</td>\n</tr>\n<tr>\n<td></td>\n<td>• Disable—Disables VDM discovery Notification</td>\n</tr>\n</tbody>\n</table>\n\n### DISABLE\n\nSets the Out-of-band interface as Disable\n\n### RESET\n\nResets the Out-of-band interface\n\n### DISCOVERYPROTOCOL\n\nSets the protocol of a connector to discover the connected backplane.\n\nAvailable connector discovery protocols are: Autodetect, UBM, SGPIO, VPP and DIRECTATTACHEDCABLE.\n\n- All: Sets the discovery protocol for all the connectors\n- DiscoveryProtocol:\n - AutoDetect*: The controller attempts to automatically detects the discovery protocol of the backplane attached to the connector.\n - UBM: The controller uses the UBM protocol to communicate with the backplane attached to the connector.\n - SGPIO: The controller uses the SGPIO protocol to communicate with the backplane attached to the connector.\n - VPP: The controller uses the VPP protocol to communicate with the backplane attached to the connector.\n- **DIRECTATTACHEDCABLE**: The controller firmware uses the direct-attached cable protocol to communicate with direct attached drives. Number of targets (Physical devices) must be set to match the cable's supported target.\n- **NUMBEROFTARGETS**: Sets the maximum number of physical devices that can be attached to the connector.\n- **NumberOfTargets**: This option is applicable and mandatory for direct-attached cable. If the number of targets is not configured correctly, the target drives may not be discovered. The possible values are 2, 4, and 8.*\n \n **Note**: * Default parameter in most circumstances.\n- **noprompt**: Do not prompt for confirmation.\n\n**EXPANDERSCANDURATION**\n\nController waits for the specified seconds to scan/discover the drives attached to the expander on the next power cycle. Set this to a nonzero value if some devices do not appear in the topology after controller boot or on rescan requests.\n\n- **duration**: Time duration a controller will wait for during expander discovery. Time duration should be in seconds.\n\n**Examples**\n\n```\nARCCONF SETCONTROLLERPARAM 1 SANITIZELOCK Freeze\nARCCONF SETCONTROLLERPARAM 1 MIXEDVOLUMES enable USERROLE crypto PASSWORD Abc@1234\nARCCONF SETCONTROLLERPARAM 1 FWLOCK enable USERROLE crypto PASSWORD Abc@1234\nARCCONF SETCONTROLLERPARAM 1 OOBINTERFACE Disable\nARCCONF SETCONTROLLERPARAM 1 OOBINTERFACE PBSI I2CAddress 0xD0 I2CCLOCKSPEED 3\nI2CCLOCKSTRETCH Enable\nARCCONF SETCONTROLLERPARAM 1 OOBINTERFACE SCTP I2CAddress 0xD0 SMBUSDEVICETYPE 1 SMBUSCHANNEL\nEnable STATICID Enable VMMNotification Enable\nARCCONF SETCONTROLLERPARAM 1 DISCOVERYPROTOCOL ALL UBM\nARCCONF SETCONTROLLERPARAM 1 DISCOVERYPROTOCOL 0 SGPIO 1 UBM 2 SGPIO\nARCCONF SETCONTROLLERPARAM 1 DISCOVERYPROTOCOL 0 VPP\nARCCONF SETCONTROLLERPARAM 1 DISCOVERYPROTOCOL 1 EXPANDERSCANDURATION 5\n```\n\n```\nARCCONF SETCONTROLLERPARAM 1 DISCOVERYPROTOCOL 0 SGPIO 1 UBM 2 AutoDetect 3\nDirectAttachedCable NUMBEROFTARGETS 8\nARCCONF SETCONTROLLERPARAM 1 DISCOVERYPROTOCOL ALL DirectAttachedCable NUMBEROFTARGETS 8\nARCCONF SETCONTROLLERPARAM 1 DISCOVERYPROTOCOL 1 DirectAttachedCable NUMBEROFTARGETS 8\n```\n\n**2.37 arcconf setmaxcache**\n\n**Description**\n\nUpdates the maxCache write cache policy for one or more logical drives.\n\n**Syntax: Write Caching**\n\n```\nARCCONF SETMAXCACHE <Controller#> LOGICALDRIVE <LD#> [<LD#> <LD#>..] MAXCACHEWRITEPOLICY <Policy> [nologs]\n```\n\n**Parameters**\n\n- **Controller#**\n \n The controller number.\n\n- **LogicalDrive#**\n \n The number of the logical drive. You can specify one or more logical drives.\nMAXCACHEWRITEPOLICY\n\nChanges the MaxCache Write Cache policy on the logical device.\n • Policy - MaxCache Write Cache Policy\n – WB - Write Back Cache Policy\n – WT - Write Through Policy\n\nExamples\n\nARCCONF SETMAXCACHE 1 LOGICALDRIVE 0 MAXCACHEWRITEPOLICY wt\n\n2.38 arcconf setname\n\nDescription\nRenames a logical drive.\n\nSyntax\n\nARCCONF SETNAME <Controller#> LOGICALDRIVE <LogicalDrive#> <New Name> [nologs]\n\nParameters\nController#\n Controller number\n\nLogicalDrive#\n The number of the logical drive to be renamed\n\nNew Name\n The new name of the logical drive, and must be of 1 to 64 characters long, using only ASCII characters.\n\nExamples\n\nARCCONF SETNAME 1 LOGICALDRIVE 1 BACKUP_A\n\n2.39 arcconf setperform\n\nDescription\nChanges controller settings based on the application type.\n\nSyntax\n\nARCCONF SETPERFORM <Controller#> MNPDELAY <Delay> [nologs]\nARCCONF SETPERFORM <Controller#> DPO <Enable | Disable> [nologs]\n\nParameters\nController#\n The controller number\n\nMNPDELAY <Delay>\n Sets the monitor and performance delay for the controller, in minutes. Default is 60 minutes.\n Valid range for delay is 0-1440 minutes.\nDPO\nDegraded mode performance optimization setting for the controller.\n • Enable—Enables DPO setting\n • Disable—Disables DPO setting\n\nExamples\n\nARCCONF SETPERFORM 1 MNPDELAY 1400\nARCCONF SETPERFORM 1 DPO enable\n\n2.40 arccconf setpower\n\nDescription\nModifies the power management settings.\n\nSyntax\nARCCONF SETPOWER <Controller#> POWERMODE <mode> SURVIVALMODE <mode> [nologs]\n\nParameters\nController#\nThe controller number.\n\nPOWERMODE\nSpecifies the power mode for the controller.\n • 1—Minimum power-Set static settings to lowest possible values and reduce power\ndynamically based on workload.\n • 2—Balanced power—Set static settings based on configuration and reduce power\ndynamically based on workload.\n • 3—Maximum performance-Set static settings to highest possible values and do not\nreduce power dynamically.\n\nNote:\n1. Some controllers do not support this mode.\n\nSURVIVALMODE\nSurvival mode allows the controller to throttle back dynamic power settings to their minimum\nwhen temperatures exceed the warning threshold.\nThis allows the server to continue running in more situations, but performance may decrease.\n • Enable—Survival mode enabled.\n • Disable—Survival mode disabled.\n\nExamples\n\nARCCONF SETPOWER 1 POWERMODE 2\nARCCONF SETPOWER 1 SURVIVALMODE 1\n2.41 arcconf setpriority\n\nDescription\nChanges a task's execution priority or a controller's global background task priority.\n\nSyntax\n```\nARCCONF SETPRIORITY <Controller#> <REBUILD|EXPAND> <New Priority> [nologs]\n```\n\nParameters\n- **Controller#**\n - The controller number\n- **New Priority**\n - LOW, MEDIUM, or HIGH. For REBUILD only: MEDIUMHIGH (if rapid rebuild priority is supported on the controller).\n- **REBUILD**\n - Sets the controller's rebuild priority.\n- **EXPAND**\n - Sets the controller's capacity expansion (OCE) priority.\n\nExamples\n```\nARCCONF SETPRIORITY 1 EXPAND LOW\nARCCONF SETPRIORITY 1 REBUILD MEDIUM\n```\n\n2.42 arcconf setstate\n\nDescription\nChanges the state of a physical device or logical device or maxcache from its current state to the designated state.\n\nSyntax\n```\nARCCONF SETSTATE <Controller#> DEVICE <Channel#> <Device#> <State> [ARRAY <AR#> [AR#] ... ] [SPARETYPE <TYPE>] [noprompt] [nologs]\nARCCONF SETSTATE <Controller#> LOGICALDRIVE <LD#> OPTIMAL [ADVANCED <option>] [noprompt] [nologs]\nARCCONF SETSTATE <Controller#> MAXCACHE <LD#> OPTIMAL [noprompt] [nologs]\n```\n\nParameters\n- **Controller#**\n - The controller number\n- **Channel#**\n - The channel number for the drive.\n- **Device#**\n - Device number for the device.\n- **LD#**\n - Logical drive number.\n**AR#**\n\nArray number.\n\n**State**\n\n- **HSP**—Create a hot spare from a ready drive. Dedicates the HSP to one or more.\n- **RDY**—Remove a hot spare designation. Attempts to change a drive from Failed to Ready.\n- **DDD**—Force a drive offline (to Failed).\n- **EED**—Enable the erased drive.\n\n**MAXCACHE**\n\nOptional keyword for maxCache devices only. Include if State is HSP or RDY, and the hot spare is for a maxCache device.\n\n- **maxCache ld#**—maxCache logical device ID to be forced optimal.\n\n**Type**\n\n- **1**—Dedicated—A dedicated spare temporarily takes over for a failed drive and can be shared between arrays.\n- **2**—Autoreplace—An autoreplace spare replaces a failed drive and cannot be shared between arrays.\n\n**SPARETYPE**\n\nSets the sparetype for the array.\n\n**Noprompt:**\n\nNo prompt for confirmation.\n\n**Examples**\n\n```bash\nARCCONF SETSTATE 1 LOGICALDRIVE 1 OPTIMAL\nARCCONF SETSTATE 1 DEVICE 0 0 DDD\nARCCONF SETSTATE 1 DEVICE 0 0 RDY\nARCCONF SETSTATE 1 DEVICE 0 0 HSP ARRAY 0 SPARETYPE 2\nARCCONF SETSTATE 1 DEVICE 0 0 HSP ARRAY 0\nARCCONF SETSTATE 1 MAXCACHE 0 OPTIMAL\n```\n\n---\n\n### 2.43 arcconf slotconfig\n\n**Description**\n\nLists the channel ID and device ID of the devices in each slot of an enclosure. A slot with no devices marked as EMPTY.\n\n**Syntax**\n\n```bash\nARCCONF SLOTCONFIG <Controller#> <ConnectorID# EnclosureID#> <Slot#> [nologs]\nARCCONF SLOTCONFIG <Controller#> <ConnectorID# EnclosureID#> MAP [nologs]\nARCCONF SLOTCONFIG <Controller#> <ConnectorName EnclosureID#> <Slot#> [nologs]\nARCCONF SLOTCONFIG <Controller#> <ConnectorName EnclosureID#> MAP [nologs]\nARCCONF SLOTCONFIG <Controller#> ALL MAP [nologs]\n```\n\n**Parameters**\n\n- **Controller#**\n \n The controller for which slot configuration is required.\n\n- **ConnectorID#**\n \n The connector ID of enclosure whose slot configuration is needed.\n\n- **ConnectorName**\n\n---\nThe connector name of enclosure whose slot configuration is needed.\n\nEnclosureID#\n\nThe enclosure where slot configuration is required.\n\nSlot#\n\nThe slot number of the drive where information is required.\n\nALL\n\nDisplay the slot configuration of all enclosures connected to controller.\n\nMAP\n\nDisplay the slot configuration of an enclosure.\n\nExamples\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ARCCONF SLOTCONFIG 1 0 2 2</td>\n<td></td>\n</tr>\n<tr>\n<td>ARCCONF SLOTCONFIG 1 CN0 1 0</td>\n<td></td>\n</tr>\n<tr>\n<td>ARCCONF SLOTCONFIG 1 CN0 2 MAP</td>\n<td></td>\n</tr>\n<tr>\n<td>ARCCONF SLOTCONFIG 1 ALL MAP</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n2.44 arcconf smp\n\nDescription\n\nSends a SAS Management Protocol (SMP) function request to a SMP target device.\n\nSyntax:\n\nARCCONF SMP <Controller#> Enclosure <Connector# Channel# Device#> Expander <Expander#> <CommandType1> [ASCII] [nologs]\nARCCONF SMP <Controller#> Enclosure <Connector# Channel# Device#> Expander <Expander#> <CommandType2> PHY <PHY#> [ASCII] [nologs]\n\nParameters\n\nController#\n\nController number.\n\nConnector# Channel# ID#\n\nConnector ID, Channel ID and Device ID of the enclosure that contains the expander.\n\nExpander#\n\nExpander number on the controller (SMP target device).\n\nPHY#\n\nThe PHY Identifier (valid only for for Discover and PHY Error Log Request).\n\nCommandType#\n\nCommandType1:\n\n• RGR—Report General Request\n• RMR—Report Manufacturer Request\n\nCommandType2:\n\n• DR—Discover Request\n• RPELR—Report PHY Error Log Request\n\nASCII\n\nDisplays the SMP response in ASCII format along with Hex formatted output.\n2.45 arcconf splitmirror\n\nDescription\nSplits an array consisting of one or more RAID 1, RAID 10, RAID 1 Triple or RAID10 Triple logical devices into two new arrays with identical contents.\n\nSyntax\n```\nARCCONF SPLITMIRROR <Controller#> ARRAY <Array#> SPLITWITHBACKUP [noprompt] [nologs]\nARCCONF SPLITMIRROR <Controller#> ARRAY <Array#> REMIRROR [noprompt] [nologs]\nARCCONF SPLITMIRROR <Controller#> ARRAY <Array#> ROLLBACK [noprompt] [nologs]\nARCCONF SPLITMIRROR <Controller#> ARRAY <Array#> ACTIVATEBACKUP [noprompt] [nologs]\n```\n\nParameters\n**Controller#**\nController number\n\n**Array#**\nArray number\n\n**SPLITWITHBACKUP**\nSplits the array into two new arrays: a primary array and a backup array, with the following characteristics:\n\n- If the original array contained RAID 1 or RAID 10 drives, the primary array will contain RAID 0 drives.\n- If the original array contained RAID 1 Triple drives, the primary array will contain RAID 1 drives.\n- If the original array contained RAID 10 Triple drives, the primary array will contain RAID 1+0 drives.\n\nThe backup array always contains RAID 0 logical drives. The primary array continues to be fully accessible to the operating system while the backup array is hidden from the operating system.\n\n**REMIRROR**\nRemirrors the array by preserving the existing data and discarding the backup array. This option re-creates the original mirrored array with the contents of the primary array.\n\n**ROLLBACK**\nRemirrors the array by rolling back to the contents of the backup array and discarding existing data. This option re-creates the mirrored array but restores its contents to the point in time when the backup array was created.\n\n⚠️ **CAUTION**\nWe do not recommend using this option while the array is online, or while the logical drive to be rolled back is mounted or in use by the operating system.\n\n**ACTIVATEBACKUP**\nActivates the backup array and makes it fully accessible to the operating system.\n### Examples\n\n- `ARCCONF SPLITMIRROR 1 ARRAY 0 SPLITWITHBACKUP`\n- `ARCCONF SPLITMIRROR 1 ARRAY 0 REMIRROR`\n- `ARCCONF SPLITMIRROR 1 ARRAY 0 ROLLBACK`\n- `ARCCONF SPLITMIRROR 1 ARRAY 0 ACTIVATEBACKUP`\n\n### 2.46 arcconf task\n\n#### Description\n\nPerforms a task on a logical drive, physical drive, array, or maxCache logical device. Uninitializes physical drives on a controller. Erases an encrypted logical drive or array, encodes (encrypts) a plaintext logical drive, and creates a new key for an encrypted logical device.\n\n#### Syntax:\n\n- `ARCCONF TASK START <Controller#> DEVICE <Channel# ID#> <secureerase> PATTERN <erasePattern> [Unrestricted] [noprompt] [nologs]`\n- `ARCCONF TASK START <Controller#> DEVICE ALL UNINITIALIZE [nologs]`\n- `ARCCONF TASK START <Controller#> DEVICE <Channel# ID#> UNINITIALIZE [nologs]`\n- `ARCCONF TASK STOP <Controller#> DEVICE <Channel# ID#> [nologs]`\n\n#### Syntax: maxCrypto Usage\n\n- `ARCCONF TASK START <Controller#> LOGICALDRIVE <LogicalDrive#> CRYPTOERASE USERROLE <userrole> PASSWORD <password>`\n- `ARCCONF TASK START <Controller#> ARRAY <Array#> CRYPTOERASE USERROLE <userrole> PASSWORD <password>`\n- `ARCCONF TASK START <Controller#> LOGICALDRIVE <LogicalDrive#> ENCODE DATA <Preserve | Discard> USERROLE <userrole> PASSWORD <password>`\n- `ARCCONF TASK START <Controller#> LOGICALDRIVE <LogicalDrive#> REKEY USERROLE <userrole> PASSWORD <password>`\n- `ARCCONF TASK START <Controller#> ARRAY <Array#> REKEY USERROLE <userrole> PASSWORD <password>`\n\n#### Parameters\n\n- **Controller#**: The controller number\n- **Channel# ID#**: Channel number and device ID for the device\n\n#### Options:\n\n- Physical device options:\n - `secureerase PATTERN <pattern>`—removes all data from the drive in a secure fashion to prevent any possible recovery of the erased data. Erase patterns:\n - 1—Zero - Initializes all blocks to zero.\n - 2—Random Zero - This erase method writes random data on the drive for the first pass then writes zeros for the second pass.\n - 3—Random Random Zero - This erase method writes random data on the drive for the first and second passes and then zeros for the third pass.\n - 4—Crypto Scramble Sanitize Method - HDDs and SSDs. Causes the physical device to change encryption keys to prevent correct decryption of previously stored information, which may cause protection information, if any, to be indeterminate.\n - 5—Block Erase Sanitize Method - SSDs only. Erase voltage is applied to all NAND cells.\n• 6—Overwrite Sanitize Method - HDDs only. Initializes blocks using complex multi-byte data pattern.\n – Unrestricted—Applicable only to the sanitize erase methods (Crypto Scramble / Block Erase / Overwrite). With the Sanitize Erase option, the physical device is available for configuration if sanitize erase fails or could not complete. If not provided, value defaults to 'Restricted'. With the default option, if Sanitize Erase fails, the only operation allowed is to start another sanitize.\n – UNINITIALIZE—When specified with ALL, clears meta-data and any OS partitions from all drives on the controller; existing data on the drive is destroyed.\n\nCryptoerase\nErases an encrypted logical drive or array. (After erasing, the logical device remains encrypted.)\n\nEncode Data <Preserve | Discard>\nEncrypts a logical drive or array, with option of preserving or discarding the original data.\n\nRekey\nGenerates a new key for encrypted devices.\n\nUSERROLE <userrole> PASSWORD <password>\nmaxCrypto user-role and password. Valid values are:\n• crypto (maxCrypto administrator)\n• user (standard user)\n\nExamples\n\n<table>\n<thead>\n<tr>\n<th>Description</th>\n<th>Syntax</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Uninitializes one or more physical drives. The uninitialized command clears meta-data and any OS partitions from a drive; existing data on the drive is destroyed.</td>\n<td>ARCCONF UNINIT <Controller#> <Channel# Drive#> [Channel# Drive#] ... [nologs] ARCCONF UNINIT <Controller#> ALL [nologs]</td>\n</tr>\n</tbody>\n</table>\n\n2.47 arcconf uninit\n\nDescription\nUninitializes one or more physical drives. The uninitialize command clears meta-data and any OS partitions from a drive; existing data on the drive is destroyed.\n\nNote: Uninitialized drives are compatible with any HBA and can be exchanged with drives on the motherboard's SATA interface.\n\nSyntax:\n\nParameters\nController#\nController number.\n\nChannel#\nThe channel number of the device to be uninitialized.\n\nDrive#\nThe drive number of the device to be uninitialized.\n**ALL**\n\nUninitializes all physical devices on the controller.\n\n**nologs**\n\nSuppresses log output for the command.\n\n**Examples**\n\n```bash\nARCCONF UNINIT 1 0 12 0 13\nARCCONF UNINIT 1 ALL\n```\nRunning ARCCONF in the UEFI Shell\n\nThis appendix describes how to run ARCCONF in the UEFI shell. UEFI/ARCCONF supports a subset of commands available on the command line. Most commands have the same form and syntax as their command line counterparts, with the exceptions noted in 3. UEFI/ARCCONF Commands. Additionally, some commands are supported in UEFI/ARCCONF only.\n\nPrerequisites\nTo run UEFI/ACCONF, ensure that your system meets these requirements:\n\n- System is running UEFI Shell v2.2 or higher\n- MSCC UEFI driver is installed:\n a. Boot the machine to the UEFI shell prompt.\n b. Type: drivers\n c. Verify that ‘MSCC UEFI Driver (version)’ is listed.\n\nStarting UEFI/ARCCONF\nTo start UEFI/ARCCONF:\n\n1. Boot the machine to the UEFI shell prompt.\n2. At the prompt, enter a command in the form:\n \n arcconf <command_name> <parameters> ...\n\n3. To see a list of supported commands, type ARCCONF at the prompt; to include pagebreaks, type ARCCONF -b. For help with a specific command, type ARCCONF <command_name> help.\n\nUEFI/ARCCONF Commands\nThe following table lists the commands supported in UEFI/ARCCONF. Follow the link in the Usage column for command forms and syntax. Where syntax differs from the command line, a separate usage statement is listed.\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Description</th>\n<th>Usage</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CONSISTENCYCHECK</td>\n<td>Toggles background consistency check modes of the controller.</td>\n<td>Usage: CONSISTENCYCHECK <Controller#> <on [Delay]off> [noprompt] Usage: CONSISTENCYCHECK <Controller#> PARALLELCOUNT <Count> Usage: CONSISTENCYCHECK <Controller#> INCONSISTENCYREPAIRPOLICY <Enable</td>\n</tr>\n<tr>\n<td>CREATE</td>\n<td>Creates a new logical drive; optionally, enables logical drive read caching, write caching.</td>\n<td>See 2.4. arcconf create</td>\n</tr>\n<tr>\n<td>DELETE</td>\n<td>Deletes a logical drive.</td>\n<td>See 2.5. arcconf delete</td>\n</tr>\n<tr>\n<td>EXPANDERLIST</td>\n<td>Returns list of disk drive expanders on a controller.</td>\n<td>See 2.7. arcconf expanderlist</td>\n</tr>\n<tr>\n<td>EXPANDERUPGRADE</td>\n<td>Allows new firmware to be flashed to an enclosure or expander.</td>\n<td>See 2.8. arcconf expanderupgrade</td>\n</tr>\n<tr>\n<td>GETCONFIG</td>\n<td>Lists information about controllers and physical drives.</td>\n<td>See 2.9. arcconf getconfig</td>\n</tr>\n<tr>\n<td>Command</td>\n<td>Description</td>\n<td>Usage</td>\n</tr>\n<tr>\n<td>------------------</td>\n<td>-----------------------------------------------------------------------------</td>\n<td>--------------------------------------------</td>\n</tr>\n<tr>\n<td>GETLOGS</td>\n<td>Provides access to controller status, event logs, and usage statistics.</td>\n<td>Usage: GETLOGS <Controller#> <Type 1></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Usage: GETLOGS <Controller> <Type 2> LOGICALDRIVE <LD#></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>see 2.10. arcconf getlogs</td>\n</tr>\n<tr>\n<td>GETVERSION</td>\n<td>Lists version information for all controllers or a specific controller's software components.</td>\n<td>See 2.13. arcconf getversion</td>\n</tr>\n<tr>\n<td>IDENTIFY</td>\n<td>Identifies a physical device by blinking its LEDs.</td>\n<td>See 2.14. arcconf identify</td>\n</tr>\n<tr>\n<td>IMAGEUPDATE</td>\n<td>Allows new firmware to be flashed to the hard drive.</td>\n<td>See 2.15. arcconf imageupdate</td>\n</tr>\n<tr>\n<td>LIST</td>\n<td>Lists controllers in the system.</td>\n<td>See 2.17. arcconf list</td>\n</tr>\n<tr>\n<td>PASSTHROUGH</td>\n<td>Sends SCSI passthrough protocol (SCSI) function request to a disk drive.</td>\n<td>See 2.22. arcconf passthrough</td>\n</tr>\n<tr>\n<td>RESCAN</td>\n<td>Check for removal of disk drives and for connection of new disk drives to the controller.</td>\n<td>See 2.25. arcconf rescan</td>\n</tr>\n<tr>\n<td>ROMUPDATE</td>\n<td>Allows new firmware and BIOS to be flashed to the controller.</td>\n<td>Usage: ROMUPDATE <Controller#> <ImagePath> [noprompt] [nologs]</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>see 2.27. arcconf romupdate</td>\n</tr>\n<tr>\n<td>SAVESUPPORTARCHIVE</td>\n<td>Saves configuration and status information.</td>\n<td>Usage: SAVESUPPORTARCHIVE [Path]</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>see 2.29. arcconf savesupportarchive</td>\n</tr>\n<tr>\n<td>SETARRAYPARAM</td>\n<td>Changes a parameter of an array.</td>\n<td>See 2.30. arcconf setarrayparam</td>\n</tr>\n<tr>\n<td>SETBOOT</td>\n<td>Sets controller as a boot device for the system.</td>\n<td>See 2.31. arcconf setboot</td>\n</tr>\n<tr>\n<td>SETCONFIG</td>\n<td>Resets the controller configuration.</td>\n<td>Usage: SETCONFIG <Controller#> <DEFAULT> [noprompt] [nologs]</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>see 2.33. arcconf setconfig</td>\n</tr>\n<tr>\n<td>SETCONNECTORMODE</td>\n<td>Change the connector operating mode.</td>\n<td>See 2.34. arcconf setconnectormode</td>\n</tr>\n<tr>\n<td>SETSTATE</td>\n<td>Changes the state of a physical device or logical device.</td>\n<td>See 2.42. arcconf setstate</td>\n</tr>\n<tr>\n<td>SLOTCONFIG</td>\n<td>Lists the channel ID and device ID of the devices in each enclosure slot.</td>\n<td>See 2.43. arcconf slotconfig</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>SMP</td>\n<td>Sends a SAS Management Protocol (SMP) function request to a SMP target device.</td>\n<td>See 2.44. arcconf smp</td>\n</tr>\n</tbody>\n</table>\n## Controller, Array, Logical and Physical Device Properties\n\nThis appendix provides detailed description of the controller, array, logical and physical device properties of ARCCONF in the command-line.\n\nTable 4-1. Controller\n\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Controller Status</td>\n<td>Overall status of the controller based on its resources.</td>\n</tr>\n<tr>\n<td>Controller Mode</td>\n<td>Operating mode of the controller.</td>\n</tr>\n<tr>\n<td>Channel description</td>\n<td>Channel description of the controller.</td>\n</tr>\n<tr>\n<td>Controller Model</td>\n<td>Model name of the controller connected to the system.</td>\n</tr>\n<tr>\n<td>Vendor ID</td>\n<td>Vendor ID of the controller.</td>\n</tr>\n<tr>\n<td>Device ID</td>\n<td>Device ID of the controller.</td>\n</tr>\n<tr>\n<td>Subsystem Vendor ID</td>\n<td>Subsystem Vendor ID of the controller.</td>\n</tr>\n<tr>\n<td>Subsystem Device ID</td>\n<td>Subsystem Device ID of the controller.</td>\n</tr>\n<tr>\n<td>Controller Serial Number</td>\n<td>A unique number assigned to the controller, used for identification and inventory purposes.</td>\n</tr>\n<tr>\n<td>Controller World Wide Name</td>\n<td>A World Wide Name (WWN) is an unique identifier of the controller.</td>\n</tr>\n<tr>\n<td>Physical Slot</td>\n<td>PCI slot number to which the controller is connected.</td>\n</tr>\n<tr>\n<td>Temperature</td>\n<td>Current temperature of the controller.</td>\n</tr>\n<tr>\n<td>Host bus type</td>\n<td>Type of host expansion bus standard.</td>\n</tr>\n<tr>\n<td>Host bus speed</td>\n<td>Speed of the host expansion bus standard in Mbps.</td>\n</tr>\n<tr>\n<td>Host bus link width</td>\n<td>Data width of the host expansion bus standard in bits.</td>\n</tr>\n<tr>\n<td>PCI Address</td>\n<td>PCI address describes the PCI address for the controller.</td>\n</tr>\n<tr>\n<td>(Domain:Bus:Device:Function)</td>\n<td></td>\n</tr>\n<tr>\n<td>Number of Ports</td>\n<td>Describes number of internal and external ports of the controller.</td>\n</tr>\n<tr>\n<td>Internal Port Count</td>\n<td>Describes number of internal ports of the controller.</td>\n</tr>\n<tr>\n<td>External Port Count</td>\n<td>Describes number of external ports of the controller.</td>\n</tr>\n<tr>\n<td>Defunct disk drive count</td>\n<td>Number of failed drive.</td>\n</tr>\n<tr>\n<td>NCQ status</td>\n<td>Native Command Queuing, or NCQ, lets SATA disk drives arrange commands into the most efficient order for optimum performance.</td>\n</tr>\n<tr>\n<td>Queue Depth</td>\n<td>Queue Depth controls the behavior of the cache write queue. This option is used to tune controller performance for video applications. The valid values are 2, 4, 8, 16, 32, or Automatic.</td>\n</tr>\n<tr>\n<td>Monitor and Performance Delay</td>\n<td>This option controls the behavior of the controller Monitor and Performance Analysis Delay and is expressed in values ranging from 0 to 1440 minutes. This option is primarily used to tune the controller's performance for video applications.</td>\n</tr>\n<tr>\n<td>Properties</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-----------------------------------------</td>\n<td>-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Elevator Sort</td>\n<td>This option controls the behavior of the controller cache write elevator sort algorithm. This option is used to tune controller performance for video applications. The possible options are Enable or Disable.</td>\n</tr>\n<tr>\n<td>Degraded Mode Performance Optimization</td>\n<td>Degraded Mode Performance Optimization setting applies to RAID 5 logical devices in Degraded mode only. Enabling this setting directs the controller to improve performance of large read requests by buffering physical drive requests. Disabling this feature forces the controller to read from the same drives multiple times. This option is used to tune controller performance for video applications. The possible options are Enable or Disable.</td>\n</tr>\n<tr>\n<td>Latency</td>\n<td>Latency describes Flexible Latency Schedule (FLS) setting. Flexible Latency Scheduler (FLS) is a controller option where the controller can re-prioritize I/O requests to prevent some requests to HDDs from timing out. Under normal operation (when FLS is disabled, or in controllers that don support FLS), the controller will sort incoming requests in order to minimize the amount of travel for the HDD read heads (Elevator Sort). This strategy works well for workloads that access sequential data, or workloads that require multiple requests from localized sectors in the drive. For highly random workloads, such as transaction processing, some requests will end up on the wrong side of the disk platter and, due to their high latency, will be marked as timed out. When FLS is enabled, it will detect these high-latency requests and apply a cut-off value, after which it will suspend elevator sorting and service the request right away.</td>\n</tr>\n<tr>\n<td>Post Prompt Timeout</td>\n<td>Post prompt timeout describes the F1/F2 Post prompt timeout for the controller during system boot.</td>\n</tr>\n<tr>\n<td>Statistics Data Collection Mode</td>\n<td>Use the Statistics Viewer to view the advanced statistics for the controllers, hard drives, SSDs, logical drives, and maxCache devices in your storage space, including virtual volumes and the maxCache container.</td>\n</tr>\n<tr>\n<td>Boot Controller</td>\n<td>Boot controller can be changed only in the offline environment and only applies to booting in Legacy BIOS Boot mode. The boot controller is the first controller that the system examines (after power-up) to find a bootable logical device or a physical device. The controller boots from the first local drive by default. It is recommended that leaving the default setting disabled to prevent an error when booting after replacing the boot volume or controller.</td>\n</tr>\n<tr>\n<td>Primary Boot Volume</td>\n<td>Describes which logical device or physical device is the primary boot volume on the current controller.</td>\n</tr>\n<tr>\n<td>Secondary Boot Volume</td>\n<td>Describes which logical device or physical device is the secondary boot volume on the current controller.</td>\n</tr>\n<tr>\n<td>Driver Name</td>\n<td>Driver name describes the name of the driver.</td>\n</tr>\n<tr>\n<td>Driver Supports SSD I/O Bypass</td>\n<td>Driver supports SSD I/O Bypass describes whether the driver supports the SSD I/O Bypass feature.</td>\n</tr>\n<tr>\n<td>Manufacturing Part Number</td>\n<td>Describes the hardware part number information about the controller.</td>\n</tr>\n<tr>\n<td>Manufacturing Spare Part Number</td>\n<td>Describes the hardware spare part number information about the controller.</td>\n</tr>\n<tr>\n<td>Manufacturing Wellness Log</td>\n<td>Describes the hardware wellness log information about the controller.</td>\n</tr>\n<tr>\n<td>Manufacturing Model</td>\n<td>Describes the manufacturing model information about the controller.</td>\n</tr>\n<tr>\n<td>Properties</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-----------------------------</td>\n<td>----------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>NVRAM Checksum Status</td>\n<td>Describes the NVRAM Checksum status.</td>\n</tr>\n</tbody>\n</table>\n| Sanitize Lock Setting | Set the sanitize lock policy of the controller. This policy will be applied to all SATA physical devices that support the feature. \n2. Freeze—Supported physical devices are freeze locked and sanitize is not allowed. \n3. Anti-Freeze—Supported physical devices are anti-freeze locked and freezing the physical devices is not allowed. |\n| Pending Sanitize Lock Setting| Sanitize lock is in pending state, reboot the system and requires all physical devices to be power cycled or hot-plugged for the lock state to be applied to the physical devices. |\n| Current Power Mode | Power mode setting that determines controller static settings based on workload. |\n| Pending Power Mode | Power mode setting is in pending state, reboot the system for the new power mode setting to be applied. |\n| Survival Mode | Enabling survival mode will allow the controller to throttle back dynamic power settings to their minimum when temperature exceeds the warning threshold. This allows the server to continue running in more situations, but performance may decrease. |\n| Cache Status | Determines the preservation status of the cache module. |\n| Cache Serial Number | A unique number assigned to the cache module. |\n| Cache memory | Cache memory size in the controller. Value in MB. |\n| Read Cache Percentage | The current read cache percent for the controller. |\n| Write Cache Percentage | The current write cache percent for the controller. |\n| No-Battery Write Cache | This setting decides the controller to enable write cache when no battery is present or when the battery fails. Values are Enable or Disable. |\n| Wait for Cache Room | This setting causes the controller to always wait for room in the read/write cache when full, instead of automatically bypassing it in favor of higher performance. |\n| Write Cache Bypass Threshold Size | All writes larger than the specified value will bypass the write cache and be written directly to the disk for non-parity RAID volumes. Value in KB. |\n\n.............continued\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n</table>\n| Configured Drives | Sets the write cache policy for the configured physical devices on the controller \n • Default: Allows the controller to control the drive write cache policy of all configured physical devices. \n • Enabled: The drive write cache for the physical device will be enabled by the controller. \n Setting to enabled can increase write performance but risks losing the data in the cache on sudden power loss to all configured physical devices. \n • Disabled: The drive write cache for the physical devices will be disabled by the controller. \n • Unchanged: Sets the physical devices factory default policy for all configured drives. |\n| Unconfigured Drives | Sets the write cache policy for the unconfigured physical devices on the controller \n • Default: The controller does not modify the drive write cache of the physical devices. \n • Enabled: The drive write cache for the physical device will be enabled by the controller. \n Setting to enabled can increase write performance but risks losing the data in the cache on sudden power loss to all unconfigured physical devices. \n • Disabled: The drive write cache for the physical devices will be disabled by the controller. |\n| HBA Drives | Sets the write cache policy for the HBA physical devices on the controller \n • Default: The controller does not modify the drive write cache of the physical devices. \n • Enabled: The drive write cache for the physical drive will be enabled by the controller. \n Setting to enabled can increase write performance but risks losing the data in the cache on sudden power loss to all physical devices. \n • Disabled: The drive write cache for the physical devices will be disabled by the controller. |\n<p>| maxCache Version | maxCache version of controller. |\n| maxCache RAID5 WriteBack Enabled | Status of write back setting for RAID5 maxCache at controller level. |\n| Logical devices/Failed/Degraded | Total number of logical devices/number of logical devices failed/number of logical devices degraded. |\n| Spare Activation Mode | Spare activation mode feature enables the controller firmware to activate a spare drive. The firmware starts rebuilding a spare drive only when a data drive fails when the mode is Failure. With the predictive failure activation mode, rebuilding can begin before the drive fails when a data drive reports a predictive failure (SMART) status which will reduce the likelihood of data loss that could occur if an additional drive fails. |\n| Background consistency check | If your controller supports background consistency check, maxView Storage Manager continually and automatically checks your logical drives for bad or inconsistent data once they're in use. |</p>\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Consistency Check Delay</td>\n<td>Determines the time interval for which a controller must be inactive before a consistency check is initiated on the physical drives that are connected to it. The value can be between 0 and 30 to specify the duration of the delay in seconds. A value of 0 disables the scan.</td>\n</tr>\n<tr>\n<td>Parallel Consistency Check Supported</td>\n<td>Status of the Parallel Consistency Check support.</td>\n</tr>\n<tr>\n<td>Parallel Consistency Check Count</td>\n<td>Parallel consistency check count describes the number of logical devices on which the controller will perform consistency check in parallel.</td>\n</tr>\n<tr>\n<td>Inconsistency Repair Policy</td>\n<td>Inconsistency repair policy searches for a single inconsistent strip and repairs the strip on that one drive only.</td>\n</tr>\n<tr>\n<td>Consistency Check Inconsistency Notify</td>\n<td>This property enables the event notification messages and serial debug log messages for mirrored volumes.</td>\n</tr>\n<tr>\n<td>Rebuild Priority</td>\n<td>Rebuild priority determines the urgency with which the controller treats an internal command to rebuild a failed logical drive. At the low setting, normal system operations take priority over a rebuild. At the medium setting, rebuilding occurs for half of the time, and normal system operations occur for the rest of the time. At the medium high setting, rebuilding is given a higher priority over normal system operations. At the high setting, the rebuild takes precedence over all other system operations.</td>\n</tr>\n<tr>\n<td>Expand Priority</td>\n<td>Determines the urgency with which the controller treats an internal command to expand an array. At the low setting level, normal system operations take priority over an array expansion. At the medium setting, expansion occurs for half of the time, and normal system operations occur for the rest of the time. At the high setting, the expansion takes precedence over all other system operations.</td>\n</tr>\n<tr>\n<td>Firmware</td>\n<td>Active firmware version of the controller.</td>\n</tr>\n<tr>\n<td>Driver</td>\n<td>Current version of driver installed on the system.</td>\n</tr>\n<tr>\n<td>Hardware Revision</td>\n<td>Describes the hardware revision information about the controller.</td>\n</tr>\n<tr>\n<td>maxCrypto Supported</td>\n<td>maxCrypto feature ensures the sensitive data is encrypted and protected by secure 256 bit AES, in-line encryption.</td>\n</tr>\n<tr>\n<td>maxCrypto Status</td>\n<td>Indicates whether maxCrypto is enabled or disabled.</td>\n</tr>\n<tr>\n<td>Crypto Officer Password</td>\n<td>Crypto officer password indicates, whether the crypto officer(Admin) has configured password or not.</td>\n</tr>\n<tr>\n<td>User Password</td>\n<td>User officer password indicates whether the user has configured password or not.</td>\n</tr>\n<tr>\n<td>Controller Password</td>\n<td>Indicates whether the controller has configured password or not.</td>\n</tr>\n<tr>\n<td>Allow New Plaintext Logical device(s)</td>\n<td>Allow new plaintext logical device(s) indicates, whether the new logical devices created can be encrypted or Plaintext (Non-Encrypted).</td>\n</tr>\n<tr>\n<td>Master Key</td>\n<td>Master key is a cryptographic secret key.</td>\n</tr>\n<tr>\n<td>FW Locked for Update</td>\n<td>Firmware locked for update prevents the updating of firmware on the controller.</td>\n</tr>\n<tr>\n<td>Properties</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>------------------------------------------------</td>\n<td>-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Password Recovery Parameters Set</td>\n<td>Crypto officer password recovery parameters indicates, whether the crypto officer has set the recovery question and answer.</td>\n</tr>\n<tr>\n<td>Controller Password Unlock Attempts Remaining</td>\n<td>Indicates the number of controller login attempts remaining.</td>\n</tr>\n<tr>\n<td>SSD I/O Bypass Mixing</td>\n<td>maxCrypto/SSD I/O bypass mixing indicates that mixing of maxCrypto and SSD I/O bypass is supported or not.</td>\n</tr>\n<tr>\n<td>maxCache Mixing</td>\n<td>Indicates whether mixing of maxCrypto and maxCache is supported or not.</td>\n</tr>\n<tr>\n<td>Crypto Account Password Unlock Attempts Remaining</td>\n<td>Indicates the number of crypto officer login attempts remaining.</td>\n</tr>\n<tr>\n<td>User Account Password Unlock Attempts Remaining</td>\n<td>Indicates the number of user login attempts remaining.</td>\n</tr>\n<tr>\n<td>Number of maxCrypto Physical devices</td>\n<td>Total number of encrypted physical device which are part of encrypted logical device.</td>\n</tr>\n<tr>\n<td>Number of maxCrypto Data Logical devices</td>\n<td>Total number of encrypted logical device.</td>\n</tr>\n<tr>\n<td>Number of maxCrypto Foreign Logical devices</td>\n<td>Encrypted Foreign Logical Device Count, Total number of encrypted foreign logical device.</td>\n</tr>\n<tr>\n<td>Number of maxCrypto Logical devices with maxCrypto off</td>\n<td>Total number of logical devices without maxCrypto.</td>\n</tr>\n<tr>\n<td>Sensor ID</td>\n<td>ID describes unique sensor identifier within the controller.</td>\n</tr>\n<tr>\n<td>Current Value</td>\n<td>Current temperature of the specific sensor.</td>\n</tr>\n<tr>\n<td>Max Value Since Powered On</td>\n<td>Maximum temperature of the specific sensor after being powered on the controller.</td>\n</tr>\n<tr>\n<td>Location</td>\n<td>Location of the specific sensor on the controller.</td>\n</tr>\n<tr>\n<td>Expander Scan Duration</td>\n<td>Time duration in seconds until which a controller waits for expander discovery.</td>\n</tr>\n<tr>\n<td>I2C Address</td>\n<td>I2C address describes the Inter-Integrated Circuit (I2C) slave address.</td>\n</tr>\n<tr>\n<td>I2C Clock Speed</td>\n<td>I2C clock speed describes the I2C clock speed.</td>\n</tr>\n<tr>\n<td>I2C Clock Stretching</td>\n<td>I2C stretching status describes the I2C clock status.</td>\n</tr>\n<tr>\n<td>Expander Scan Time-out</td>\n<td>Maximum time(seconds) that controller waits for expander scanning devices completion.</td>\n</tr>\n<tr>\n<td>Reboot Required Reasons</td>\n<td>Have controller settings changed requiring reboot. Property provides list of reasons for a reboot.</td>\n</tr>\n<tr>\n<td>Backup Power Status</td>\n<td>The backup power status of the controller.</td>\n</tr>\n<tr>\n<td>Battery/Capacitor Pack Count</td>\n<td>The total installed battery pack count.</td>\n</tr>\n<tr>\n<td>Hardware Error</td>\n<td>The backup hardware error.</td>\n</tr>\n<tr>\n<td>OOB Interface</td>\n<td>Out of Band Interface setting.</td>\n</tr>\n</tbody>\n</table>\n### Properties\n\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Pending OOB Interface</td>\n<td>Out of Band Interface is in pending state, reboot the system for the new setting to be applied.</td>\n</tr>\n<tr>\n<td>I2C Address</td>\n<td>The Inter-Integrated Circuit(I2C) slave address.</td>\n</tr>\n<tr>\n<td>Pending I2C Address</td>\n<td>I2C address is in pending state, reboot the system for the new setting to be applied.</td>\n</tr>\n<tr>\n<td>Power settings</td>\n<td>Power setting information (The total board power, which is the total power of all the power sensors plus a static board value.)</td>\n</tr>\n</tbody>\n</table>\n\n#### PBSI related properties\n\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>I2C Clock Speed</td>\n<td>I2C clock speed. Value in KHz.</td>\n</tr>\n<tr>\n<td>Pending I2C Clock Speed</td>\n<td>I2C clock speed is in pending state, reboot the system for the new setting to be applied.</td>\n</tr>\n<tr>\n<td>I2C Clock Stretching</td>\n<td>I2C clock stretching is enabled or disabled.</td>\n</tr>\n<tr>\n<td>Pending I2C Clock Stretching</td>\n<td>I2C clock stretching is in pending state, reboot the system for the new setting to be applied.</td>\n</tr>\n</tbody>\n</table>\n\n#### MCTP related properties\n\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SMBus Device Type</td>\n<td>System Management(SM) Bus Device Type</td>\n</tr>\n<tr>\n<td>SMBus Channel</td>\n<td>System Management(SM) Bus Channel setting</td>\n</tr>\n<tr>\n<td>Static EIDs Use On Initialization</td>\n<td>Static End Point Identifiers(EID) usage during initialization</td>\n</tr>\n<tr>\n<td>VDM Notification</td>\n<td>Vendor Defined Message(VDM) discovery notification</td>\n</tr>\n<tr>\n<td>Pending SMBus Device Type</td>\n<td>SMBus Device Type is in pending state, reboot the system for the new setting to be applied.</td>\n</tr>\n<tr>\n<td>Pending SMBus Channel</td>\n<td>SMBus Channel is in pending state, reboot the system for the new setting to be applied.</td>\n</tr>\n<tr>\n<td>Pending Static EIDs Use On Initialization</td>\n<td>Static EIDs Use On Initialization is in pending state, reboot the system for the new setting to be applied.</td>\n</tr>\n<tr>\n<td>Pending VDM Notification</td>\n<td>VDM Notification is in pending state, reboot the system for the new setting to be applied.</td>\n</tr>\n</tbody>\n</table>\n\n### Table 4-2. Array\n\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Array Number</td>\n<td>ID describes unique array identifier within the controller.</td>\n</tr>\n<tr>\n<td>Status</td>\n<td>Status of array is based on health of the member disk drives.</td>\n</tr>\n<tr>\n<td>Name</td>\n<td>Name describes unique name of an array.</td>\n</tr>\n<tr>\n<td>Transformation Status</td>\n<td>Transformation status indicates whether the array is transforming or not.</td>\n</tr>\n<tr>\n<td>Interface</td>\n<td>Disk drives that are the member of array can have interface type such SAS, SATA, SAS SSD, and SATA SSD. The interface type of array is based on the member disk drives interface type.</td>\n</tr>\n</tbody>\n</table>\n### Properties\n\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Total size</td>\n<td>Total usable size is the total space available in the array for creating logical device.</td>\n</tr>\n<tr>\n<td>Unused Size</td>\n<td>Unused size is the free space available to create new logical device to store the data.</td>\n</tr>\n<tr>\n<td>Block size</td>\n<td>Block size indicates the maximum size of data block on disk drives that are member of an array (can be 512 Bytes or 4K).</td>\n</tr>\n<tr>\n<td>Array Utilization</td>\n<td>Total space utilization of an array.</td>\n</tr>\n<tr>\n<td>Type</td>\n<td>Describes the type of the array such as data array, backup array, and so on.</td>\n</tr>\n<tr>\n<td>Associated Split Mirror Array</td>\n<td>Name of its associated array, if array is of type split mirror.</td>\n</tr>\n<tr>\n<td>Spare Rebuild Mode</td>\n<td>Spare Rebuild mode describes the spare type for the array. It can be "dedicated" or "auto replace" if the array is valid.</td>\n</tr>\n<tr>\n<td>SSD I/O Bypass</td>\n<td>SSD I/O Bypass enables an optimized data path to high performance solid state drives. The optimized path bypasses the controllers RAID processing components and sends I/O directly to the drives.</td>\n</tr>\n</tbody>\n</table>\n\n### Logical Device\n\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Logical Device Number</td>\n<td>ID describes unique logical device identifier within the controller.</td>\n</tr>\n<tr>\n<td>Logical Device Name</td>\n<td>Logical device name can be of maximum 64 characters and it should contain only ASCII characters in Operation System.</td>\n</tr>\n<tr>\n<td>Disk Name</td>\n<td>Name of the logical disk drive.</td>\n</tr>\n<tr>\n<td>Block Size of member drives</td>\n<td>Maximum size of data block on disk drives which are RAID member of logical device (can be 512 Bytes or 4K).</td>\n</tr>\n<tr>\n<td>Array</td>\n<td>Identifier of the Array on which the logical device.</td>\n</tr>\n<tr>\n<td>RAID level</td>\n<td>RAID level on which the logical device has been created.</td>\n</tr>\n<tr>\n<td>Unique Identifier</td>\n<td>The logical device unique identifier.</td>\n</tr>\n<tr>\n<td>Status of Logical Device</td>\n<td>Status of logical device based on health of RAID members of logical device.</td>\n</tr>\n<tr>\n<td>maxCache state</td>\n<td>State of the associated maxCache logical device.</td>\n</tr>\n<tr>\n<td>Additional details</td>\n<td>Describes the way of logical device creation.</td>\n</tr>\n<tr>\n<td>Parity Initialization Status</td>\n<td>RPI status of this logical device.</td>\n</tr>\n<tr>\n<td>maxCache Status</td>\n<td>Status of maxCache.</td>\n</tr>\n<tr>\n<td>Size</td>\n<td>Logical device size.</td>\n</tr>\n<tr>\n<td>Parity Space</td>\n<td>The parity space of the logical device.</td>\n</tr>\n<tr>\n<td>Stripe-unit size</td>\n<td>Stripe size is the amount of data (in KB) written to one disk drive, before moving to the next disk drive in the logical device. Stripe size options vary, depending on your controller and RAID level.</td>\n</tr>\n<tr>\n<td>Properties</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>--------------------------------</td>\n<td>-----------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Full Stripe Size</td>\n<td>Full stripe size refers to the combined size of all the strips across all physical devices, excluding parity-only devices.</td>\n</tr>\n<tr>\n<td>Cache Line Size</td>\n<td>Specifies the cache line size (KB).</td>\n</tr>\n<tr>\n<td>Interface Type</td>\n<td>Disk drives which are the member of logical can have interface type such SAS, SATA, SAS SSD and SATA SSD.</td>\n</tr>\n<tr>\n<td>Device Type</td>\n<td>Indicates logical drive is of type data or cache.</td>\n</tr>\n<tr>\n<td>Heads</td>\n<td>Indicates the predefined space set aside for RAID redundant information on a logical device.</td>\n</tr>\n<tr>\n<td>Sectors Per Track</td>\n<td>Specifies the number of sectors that are to comprise each track.</td>\n</tr>\n<tr>\n<td>Cylinders</td>\n<td>Indicates the set of all tracks having equal diameter in a logical device.</td>\n</tr>\n<tr>\n<td>Caching</td>\n<td>Indicates the setting of cache used for this logical device.</td>\n</tr>\n<tr>\n<td>Mount Points</td>\n<td>Describes the operating system device names of the logical device and vice versa.</td>\n</tr>\n<tr>\n<td>Associated Logical Id</td>\n<td>Associated logical device for maxCache.</td>\n</tr>\n<tr>\n<td>maxCache write cache policy</td>\n<td>maxCache policy setting to WT or WB.</td>\n</tr>\n<tr>\n<td>Backup Creation Timestamp</td>\n<td>Split Mirror Set Backup logical creation time.</td>\n</tr>\n<tr>\n<td>LD Acceleration Method</td>\n<td>Setting of the LD acceleration method. Controller cache or SSD I/O Bypass or maxCache.</td>\n</tr>\n<tr>\n<td>Volume Unique Identifier</td>\n<td>Logical device unique string identifier.</td>\n</tr>\n<tr>\n<td>Plaintext (Non-Encrypted) Logical Device</td>\n<td>Setting to identify a non-encrypted logical device.</td>\n</tr>\n<tr>\n<td>Volatile maxCrypto Keys</td>\n<td>Setting to identify if logical device supports Volatile key.</td>\n</tr>\n<tr>\n<td>Boot Type</td>\n<td>A bootable logical device is a logical device that the system can attempt to boot from after a system power-on. A controller can have up to two bootable logical device, where one is a primary boot logical device and the other a secondary boot logical device. When the system looks at a controller for a boot logical device, it will first attempt to boot from a primary boot logical device, and if that fails, then it will attempt to boot from a secondary boot logical device.</td>\n</tr>\n<tr>\n<td>maxCrypto</td>\n<td>Setting of the maxCrypto for the logical device.</td>\n</tr>\n<tr>\n<td>Encrypted</td>\n<td>Indicate user whether the logical device is encrypted or not.</td>\n</tr>\n</tbody>\n</table>\n\n**maxCache statistics**\n\n<table>\n<thead>\n<tr>\n<th>maxCache statistics</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Read Cache Hits</td>\n</tr>\n<tr>\n<td>Read Cache Miss (Total)</td>\n</tr>\n<tr>\n<td>Read Cache Hit Rate</td>\n</tr>\n<tr>\n<td>Write Cache Hits</td>\n</tr>\n</tbody>\n</table>\n### Properties\n\n<table>\n<thead>\n<tr>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Write Cache Miss (Total)</td>\n</tr>\n<tr>\n<td>Write Cache Hit Rate</td>\n</tr>\n</tbody>\n</table>\n\n## Table 4-4. Physical Device\n\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SED Security Status</td>\n<td>SED Security status is locked or not?</td>\n</tr>\n<tr>\n<td>SED Qualification Status</td>\n<td>Device qualification status is in progress or failed.</td>\n</tr>\n<tr>\n<td>Device</td>\n<td>The SCSI ID for a physical device reported by the controller.</td>\n</tr>\n<tr>\n<td>Device Type</td>\n<td>Type of physical device such as "hard disk drive", "solid state drive" or</td>\n</tr>\n<tr>\n<td></td>\n<td>"shingled magnetic recording (SMR) hard disk drive."</td>\n</tr>\n<tr>\n<td>State</td>\n<td>Current state of the physical device based on the operations done on it.</td>\n</tr>\n<tr>\n<td>Drive has stale RIS data</td>\n<td>Specifies whether the physical device has stale RIS data.</td>\n</tr>\n<tr>\n<td>Disk name</td>\n<td>Name of the physical disk drive in Operating System.</td>\n</tr>\n<tr>\n<td>Block Size</td>\n<td>Maximum size of the data block on disk drives that are RAID member of the</td>\n</tr>\n<tr>\n<td></td>\n<td>logical device (can be 512 Bytes or 4K).</td>\n</tr>\n<tr>\n<td>Dedicated Spare for drive</td>\n<td>If drive is acting as spare.</td>\n</tr>\n<tr>\n<td>Transfer Speed</td>\n<td>Description of the drive speed.</td>\n</tr>\n<tr>\n<td>Reported Channel,Device (T:L)</td>\n<td>The channel ID and SCSI Device ID to which the physical device is</td>\n</tr>\n<tr>\n<td></td>\n<td>connected.</td>\n</tr>\n<tr>\n<td>Vendor</td>\n<td>Physical device manufacturer name.</td>\n</tr>\n<tr>\n<td>Model</td>\n<td>Product model; name of the physical device.</td>\n</tr>\n<tr>\n<td>Firmware</td>\n<td>Firmware version of the physical device.</td>\n</tr>\n<tr>\n<td>Serial number</td>\n<td>Serial number of the physical device.</td>\n</tr>\n<tr>\n<td>World Wide Name</td>\n<td>Reported world wide name provided by the manufacturer.</td>\n</tr>\n<tr>\n<td>Total Size</td>\n<td>Total data storage capacity of the physical device.</td>\n</tr>\n<tr>\n<td>Reserved Size</td>\n<td>Reserved space for internal use.</td>\n</tr>\n<tr>\n<td>Used Size</td>\n<td>Used space of the drive.</td>\n</tr>\n<tr>\n<td>Unused Size</td>\n<td>Unused space of the drive.</td>\n</tr>\n<tr>\n<td>S.M.A.R.T.</td>\n<td>SMART supported.</td>\n</tr>\n<tr>\n<td>S.M.A.R.T. warnings</td>\n<td>Any SMART error reported in the physical device.</td>\n</tr>\n<tr>\n<td>SSD</td>\n<td>If drive type is SSD.</td>\n</tr>\n<tr>\n<td>Device-On-Boot Connector</td>\n<td>Device connected through the boot connector.</td>\n</tr>\n<tr>\n<td>Properties</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-----------------------------</td>\n<td>-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>NCQ status</td>\n<td>Indicates whether the native command queuing is enabled/disabled on this physical device.</td>\n</tr>\n<tr>\n<td>NCQ supported</td>\n<td>Specifies whether this physical device supports native command queuing.</td>\n</tr>\n<tr>\n<td>Rotational Speed</td>\n<td>Indicates the rotational speed of the physical device.</td>\n</tr>\n<tr>\n<td>Current Temperature</td>\n<td>Current temperature of the physical device.</td>\n</tr>\n<tr>\n<td>Maximum Temperature</td>\n<td>The maximum temperature reported by the physical device.</td>\n</tr>\n<tr>\n<td>Threshold Temperature</td>\n<td>The threshold temperature reported by the physical device.</td>\n</tr>\n<tr>\n<td>PHY Count</td>\n<td>Drive PHY count.</td>\n</tr>\n<tr>\n<td>Drive Configuration Type</td>\n<td>Determines the presence/type of logical devices of which this physical device is a part.</td>\n</tr>\n<tr>\n<td>Mount Point(s)</td>\n<td>Mount point(s) describes the operating system device names of the physical device.</td>\n</tr>\n<tr>\n<td>Drive Exposed to OS</td>\n<td>Indicates whether the physical device is exposed to the operating system.</td>\n</tr>\n<tr>\n<td>Sanitize Erase Support</td>\n<td>Specifies whether the sanitize erase is supported by this physical device.</td>\n</tr>\n<tr>\n<td>Sanitize Lock Freeze Support</td>\n<td>Specifies whether the sanitize freeze is supported by this physical device.</td>\n</tr>\n<tr>\n<td>Sanitize Lock Anti-Freeze Support</td>\n<td>Specifies whether the sanitize lock anti-freeze is supported by this physical device.</td>\n</tr>\n<tr>\n<td>Sanitize Lock Setting</td>\n<td>Sanitize Lock Setting information.</td>\n</tr>\n<tr>\n<td>Usage Remaining</td>\n<td>SSD life utilization.</td>\n</tr>\n<tr>\n<td>SSD Smart Trip Wearout</td>\n<td>SSD wear out occurred.</td>\n</tr>\n<tr>\n<td>56 Day Warning Present</td>\n<td>SSD have lesser than or equal to 56 days of the calculated usage left.</td>\n</tr>\n<tr>\n<td>Drive Unique ID</td>\n<td>ID to uniquely identify the physical device.</td>\n</tr>\n<tr>\n<td>Last Failure Reason</td>\n<td>Describes previous drive failure reason.</td>\n</tr>\n<tr>\n<td>Encrypted</td>\n<td>A SED (or Self-Encrypting Drive) is a type of hard drive that automatically and continuously encrypts the data on the drive without any user interaction.</td>\n</tr>\n<tr>\n<td>Volatile maxCrypto Key</td>\n<td>Whether this device has volatile keys.</td>\n</tr>\n<tr>\n<td>Interface Type</td>\n<td>Interface type supported by the physical device.</td>\n</tr>\n<tr>\n<td>Boot Type</td>\n<td>A bootable physical device is a physical device from which the system attempts to boot after a system power-on. A controller can have up to two bootable physical devices, where one is a primary boot physical device and the other is a secondary boot physical device. When the system looks at a controller for a boot physical device, it will first attempt to boot from a primary boot physical device, and if that fails, then it will attempt to boot from a secondary boot physical device.</td>\n</tr>\n<tr>\n<td>Encrypted Drive</td>\n<td>Indicates whether this physical device is a part of any encrypted logical device.</td>\n</tr>\n<tr>\n<td>Properties</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------------------------------</td>\n<td>-----------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Drive Encryption Capability</td>\n<td>Device is Self-Encryption Drive or not?</td>\n</tr>\n<tr>\n<td><strong>Drive PHY information</strong></td>\n<td></td>\n</tr>\n<tr>\n<td>Negotiated Physical Link Rate</td>\n<td>Indicating the negotiated physical link rate on all the PHYs of this device.</td>\n</tr>\n<tr>\n<td>Negotiated Logical Link Rate</td>\n<td>Indicating the negotiated logical link rate on all the PHYs of this device.</td>\n</tr>\n<tr>\n<td>Maximum Link Rate</td>\n<td>Maximum possible link rate for a PHY.</td>\n</tr>\n<tr>\n<td>Negotiated Link Rate</td>\n<td>PHY negotiated link rate.</td>\n</tr>\n<tr>\n<td><strong>Runtime Error Counters</strong></td>\n<td></td>\n</tr>\n<tr>\n<td>Hardware Error Count</td>\n<td>Hardware Error Count</td>\n</tr>\n<tr>\n<td>Medium Error Count</td>\n<td>Medium Error Count</td>\n</tr>\n<tr>\n<td>Parity Error Count</td>\n<td>Parity Error Count</td>\n</tr>\n<tr>\n<td>Link Failure Count</td>\n<td>Link Failure Count</td>\n</tr>\n<tr>\n<td>Aborted Command Count</td>\n<td>Aborted Command Count</td>\n</tr>\n<tr>\n<td>SMART Warning Count</td>\n<td>SMART Warning Count</td>\n</tr>\n<tr>\n<td><strong>Device Error Counters</strong></td>\n<td></td>\n</tr>\n<tr>\n<td>Aborted Commands</td>\n<td>Aborted Commands</td>\n</tr>\n<tr>\n<td>Bad Target Errors</td>\n<td>Bad Target Errors</td>\n</tr>\n<tr>\n<td>ECC Recovered Read Errors</td>\n<td>ECC Recovered Read Errors</td>\n</tr>\n<tr>\n<td>Failed Read Recovers</td>\n<td>Failed Read Recovers</td>\n</tr>\n<tr>\n<td>Failed Write Recovers</td>\n<td>Failed Write Recovers</td>\n</tr>\n<tr>\n<td>Format Errors</td>\n<td>Format Errors</td>\n</tr>\n<tr>\n<td>Hardware Errors</td>\n<td>Hardware Errors</td>\n</tr>\n<tr>\n<td>Hard Read Errors</td>\n<td>Hard Read Errors</td>\n</tr>\n<tr>\n<td>Hard Write Errors</td>\n<td>Hard Write Errors</td>\n</tr>\n<tr>\n<td>Hot Plug Count</td>\n<td>Hot Plug Count</td>\n</tr>\n<tr>\n<td>Media Failures</td>\n<td>Media Failures</td>\n</tr>\n<tr>\n<td>Not Ready Errors</td>\n<td>Not Ready Errors</td>\n</tr>\n<tr>\n<td>Other Time Out Errors</td>\n<td>Other Time Out Errors</td>\n</tr>\n<tr>\n<td>Predictive Failures</td>\n<td>Predictive Failures</td>\n</tr>\n<tr>\n<td>Retry Recovered Read Errors</td>\n<td>Retry Recovered Read Errors</td>\n</tr>\n<tr>\n<td>Retry Recovered Write Errors</td>\n<td>Retry Recovered Write Errors</td>\n</tr>\n<tr>\n<td>SCSI Bus Faults</td>\n<td>SCSI Bus Faults</td>\n</tr>\n<tr>\n<td>Properties</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>--------------------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>Sectors Reads</td>\n<td>Sectors Reads</td>\n</tr>\n<tr>\n<td>Sectors Written</td>\n<td>Sectors Written</td>\n</tr>\n<tr>\n<td>Service Hours</td>\n<td>Service Hours</td>\n</tr>\n</tbody>\n</table>\n\n**Table 4-5. Connector Information**\n\n<table>\n<thead>\n<tr>\n<th>Properties</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Connector</td>\n<td>The ID for a connector reported by the controller</td>\n</tr>\n<tr>\n<td>Functional Mode</td>\n<td>Operating mode of the connector. Possible values RAID(Hide RAW), HBA and Mixed.</td>\n</tr>\n<tr>\n<td>Connector Location</td>\n<td>Physical location of the connector on the controller.</td>\n</tr>\n<tr>\n<td>SAS Address</td>\n<td>SAS address of the connector.</td>\n</tr>\n<tr>\n<td>Current Discovery Protocol</td>\n<td>The current backplane discovery protocol connector operates in.</td>\n</tr>\n<tr>\n<td>Pending Discovery Protocol</td>\n<td>Backplane discovery protocol is in pending state, reboot the system for the new setting to be applied.</td>\n</tr>\n<tr>\n<td>PHY Count</td>\n<td>The number of PHYs the connector has.</td>\n</tr>\n<tr>\n<td>Current Number of Targets</td>\n<td>Number of devices supported on the connector when the protocol is set to “Direct-Attached Cable”.</td>\n</tr>\n<tr>\n<td>Pending Number of Targets</td>\n<td>Number of targets has changed and is in pending state, reboot the system for the new value to be applied. Valid only for discovery protocol “Direct-Attached Cable”.</td>\n</tr>\n</tbody>\n</table>\n5. **Revision History**\n\nThe revision history describes the changes that were implemented in the document. The changes are listed by revision, starting with the most current publication.\n\n<table>\n<thead>\n<tr>\n<th>Revision</th>\n<th>Date</th>\n<th>Description</th>\n</tr>\n</thead>\n</table>\n| D | 11/2021 | ● Updated the syntax/description/examples of arconf atapassword, arconf consistencycheck, arconf create, arconf expanderupgrade, arconf getlogs, arconf getstatus, arconf identify, arconf maxcrypto, arconf maxcryptoaccounts, arconf maxcryptokey, arconf phyerrorlog, arconf savesupportarchive, arconf setarrayparam, arconf setboot, arconf setcache, arconf setcontrollerparam, arconf setperform, arconf setpower, arconf setstate, arconf slotconfig, arconf smp, and arconf splitmirror \n● Removed arconf restatstatisticscounter and arconf setstatsdatacollection |\n<table>\n<thead>\n<tr>\n<th>Revision</th>\n<th>Date</th>\n<th>Description</th>\n</tr>\n</thead>\n</table>\n| C | 07/2021 | - Updated the Introduction section \n| | | - Updated the description in arconf consistencycheck \n| | | - Updated description of Wcache, CacheLineSize <CACHELINESIZE>, and Legs <LEG> in arconf create \n| | | - Updated syntax and description of options parameter in arconf task \n| | | - Added DEBUGTOKEN in arconf getconfig \n| | | - Updated syntax of arconf getstatus \n| | | - Updated the description for Mode# parameter in arconf imageupdate \n| | | - Updated parameters in arconf getlogs \n| | | - Updated the Controller, Array, Logical and Physical Device Properties section \n| | | - Added a new table “Connector Information” in the Controller, Array, Logical and Physical Device Properties section |\n| B | 05/2021 | - Added VPP to DISCOVERYPROTOCOL in arconf setcontrollerparam \n| | | - Removed CONSOLIDATESSPACE from arconf setarrayparam \n| | | - Updated CachePolicy in arconf setcache \n| | | - Updated the description for Configured Drives, Unconfigured Drives, HBA Drives in the Controller, Array, Logical and Physical Device Properties section \n| A | 02/2021 | Initial Revision (previously, ESC-2161616) |\nThe Microchip Website\n\nMicrochip provides online support via our website at www.microchip.com/. 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Stephenson, Ph.D.\nAssociate Professor\n\n30 June 1987\n\nEngineering Computer Graphics Laboratory\nCivil Engineering Department\nBrigham Young University\nProvo, Utah 84602\n(801) 378-2812\n\nReport No. ECGL-87-03\nDISCLAIMER\nfor\nRASTER GRAPHICS DISPLAY LIBRARY\n\nNeither Brigham Young University nor their employees makes any warranty expressed or implied, or assumes any legal responsibility for the accuracy, completeness or usefulness of the computer programs described in this document.\nCHAPTER TWO\nTECHNICAL REFERENCES .................................. 2.1\nSee pages iii and vii for indices of the routines.\n\nCHAPTER THREE\nCOMMON BLOCKS ............................................. 3.1\nCATTRI ......................................................... 3.2\nCFLAGS ......................................................... 3.4\nCHFWAS ......................................................... 3.5\nCLIMIT ......................................................... 3.7\nCMEMRY ......................................................... 3.9\nHIDSTF ......................................................... 3.10\nKEEP ........................................................... 3.11\nMASTER ......................................................... 3.12\nPIXSTF ......................................................... 3.13\nRESOLT ......................................................... 3.14\nVEWSTF ......................................................... 3.15\nZBUFER ......................................................... 3.16\n\nCHAPTER FOUR\nINCLUDE FILES ............................................... 4.1\nANIM.INC ..................................................... 4.2\nCVER.INC ..................................................... 4.3\nFNCST.INC ................................................... 4.4\nHIDN.INC ..................................................... 4.5\nMOVL.INC ..................................................... 4.7\nMSTR.INC ..................................................... 4.8\nUSER.INC ..................................................... 4.10\n\nAPPENDIX A\nLINK MAP .................................................... A.1\n\nAPPENDIX B\nAN INTRODUCTION TO HIERARCHICAL DATA STRUCTURES ........... B.1\nHierarchical Data Structure Terms ................................ B.2\nWhat Are Groups And Items? .................................... B.2\n\nAPPENDIX C\nSOFTWARE INSTALLATION .................................... C.1\nInstallation ................................................. C.2\nBugs, Problems, and Comments .................................. C.2\n\nTABLE OF CONTENTS ii\n<table>\n<thead>\n<tr>\n<th>Subroutine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ACTGRP</td>\n<td>2.2</td>\n</tr>\n<tr>\n<td>ADDCAL</td>\n<td>2.3</td>\n</tr>\n<tr>\n<td>ANFILI</td>\n<td>2.4</td>\n</tr>\n<tr>\n<td>ANFILS</td>\n<td>2.5</td>\n</tr>\n<tr>\n<td>ANIDRV</td>\n<td>2.6</td>\n</tr>\n<tr>\n<td>AROCLR</td>\n<td>2.7</td>\n</tr>\n<tr>\n<td>ATFROM</td>\n<td>2.8</td>\n</tr>\n<tr>\n<td>AUTOON</td>\n<td>2.9</td>\n</tr>\n<tr>\n<td>BEGANI</td>\n<td>2.10</td>\n</tr>\n<tr>\n<td>CAMERA</td>\n<td>2.11</td>\n</tr>\n<tr>\n<td>CENTER</td>\n<td>2.12</td>\n</tr>\n<tr>\n<td>CHRNUM</td>\n<td>2.13</td>\n</tr>\n<tr>\n<td>CLPLIN</td>\n<td>2.14</td>\n</tr>\n<tr>\n<td>CLPPOL</td>\n<td>2.15</td>\n</tr>\n<tr>\n<td>CLPPZE</td>\n<td>2.16</td>\n</tr>\n<tr>\n<td>CNTBAR</td>\n<td>2.17</td>\n</tr>\n<tr>\n<td>CNTPRT</td>\n<td>2.18</td>\n</tr>\n<tr>\n<td>COLERR</td>\n<td>2.19</td>\n</tr>\n<tr>\n<td>COLORS</td>\n<td>2.20</td>\n</tr>\n<tr>\n<td>COPNUM</td>\n<td>2.21</td>\n</tr>\n<tr>\n<td>DEFAULT</td>\n<td>2.22</td>\n</tr>\n<tr>\n<td>DEFINE</td>\n<td>2.23</td>\n</tr>\n<tr>\n<td>DELETE</td>\n<td>2.24</td>\n</tr>\n<tr>\n<td>DISALL</td>\n<td>2.25</td>\n</tr>\n<tr>\n<td>DISTXT</td>\n<td>2.26</td>\n</tr>\n<tr>\n<td>DODITH</td>\n<td>2.27</td>\n</tr>\n<tr>\n<td>DRWABS</td>\n<td>2.28</td>\n</tr>\n<tr>\n<td>DRNBOR</td>\n<td>2.29</td>\n</tr>\n<tr>\n<td>ERASE</td>\n<td>2.30</td>\n</tr>\n<tr>\n<td>EXTCOP</td>\n<td>2.31</td>\n</tr>\n<tr>\n<td>FNDFRM</td>\n<td>2.32</td>\n</tr>\n<tr>\n<td>FOURVW</td>\n<td>2.33</td>\n</tr>\n<tr>\n<td>FRINGE</td>\n<td>2.34</td>\n</tr>\n<tr>\n<td>FRNBAR</td>\n<td>2.35</td>\n</tr>\n<tr>\n<td>GENTXT</td>\n<td>2.36</td>\n</tr>\n<tr>\n<td>GETAGR</td>\n<td>2.37</td>\n</tr>\n<tr>\n<td>GETCLP</td>\n<td>2.38</td>\n</tr>\n<tr>\n<td>GETCOM</td>\n<td>2.39</td>\n</tr>\n<tr>\n<td>GETCOP</td>\n<td>2.40</td>\n</tr>\n<tr>\n<td>GETDEF</td>\n<td>2.41</td>\n</tr>\n<tr>\n<td>GETGRU</td>\n<td>2.42</td>\n</tr>\n<tr>\n<td>GETITM</td>\n<td>2.43</td>\n</tr>\n<tr>\n<td>GETLIM</td>\n<td>2.44</td>\n</tr>\n<tr>\n<td>GETNUM</td>\n<td>2.45</td>\n</tr>\n<tr>\n<td>GETWND</td>\n<td>2.46</td>\n</tr>\n<tr>\n<td>ALPHABETIZED LIST</td>\n<td></td>\n</tr>\n<tr>\n<td>-------------------</td>\n<td></td>\n</tr>\n<tr>\n<td>GETXT ...........................</td>\n<td>2.47</td>\n</tr>\n<tr>\n<td>GLBACT ...................................</td>\n<td>2.48</td>\n</tr>\n<tr>\n<td>GLBAXS ....................................</td>\n<td>2.49</td>\n</tr>\n<tr>\n<td>GRAINT ....................................</td>\n<td>2.50</td>\n</tr>\n<tr>\n<td>GTUROX ....................................</td>\n<td>2.51</td>\n</tr>\n<tr>\n<td>GTUROY .....................................</td>\n<td>2.52</td>\n</tr>\n<tr>\n<td>GTUROZ .....................................</td>\n<td>2.53</td>\n</tr>\n<tr>\n<td>GTUSCL .....................................</td>\n<td>2.54</td>\n</tr>\n<tr>\n<td>GTUTRN .....................................</td>\n<td>2.55</td>\n</tr>\n<tr>\n<td>HIDLIN .....................................</td>\n<td>2.56</td>\n</tr>\n<tr>\n<td>HIDSUR ....................................</td>\n<td>2.57</td>\n</tr>\n<tr>\n<td>HUDITM ....................................</td>\n<td>2.58</td>\n</tr>\n<tr>\n<td>INCONG ....................................</td>\n<td>2.59</td>\n</tr>\n<tr>\n<td>INITIGI ....................................</td>\n<td>2.60</td>\n</tr>\n<tr>\n<td>INQBGC ....................................</td>\n<td>2.61</td>\n</tr>\n<tr>\n<td>INQBOX ....................................</td>\n<td>2.62</td>\n</tr>\n<tr>\n<td>INQCNT ....................................</td>\n<td>2.63</td>\n</tr>\n<tr>\n<td>INQCON ....................................</td>\n<td>2.64</td>\n</tr>\n<tr>\n<td>INQDEV ....................................</td>\n<td>2.65</td>\n</tr>\n<tr>\n<td>INQDSP ....................................</td>\n<td>2.66</td>\n</tr>\n<tr>\n<td>INQDST ....................................</td>\n<td>2.67</td>\n</tr>\n<tr>\n<td>INQFLG ....................................</td>\n<td>2.68</td>\n</tr>\n<tr>\n<td>INQFNC ....................................</td>\n<td>2.69</td>\n</tr>\n<tr>\n<td>INQFOG ....................................</td>\n<td>2.70</td>\n</tr>\n<tr>\n<td>INQFRM ....................................</td>\n<td>2.71</td>\n</tr>\n<tr>\n<td>INQFRN ....................................</td>\n<td>2.72</td>\n</tr>\n<tr>\n<td>INQGLB ....................................</td>\n<td>2.73</td>\n</tr>\n<tr>\n<td>INQHELP ....................................</td>\n<td>2.74</td>\n</tr>\n<tr>\n<td>INQLEVEL ..................................</td>\n<td>2.75</td>\n</tr>\n<tr>\n<td>INQLIT ....................................</td>\n<td>2.76</td>\n</tr>\n<tr>\n<td>INQPER ....................................</td>\n<td>2.77</td>\n</tr>\n<tr>\n<td>INQPLT ....................................</td>\n<td>2.78</td>\n</tr>\n<tr>\n<td>INQQAT ....................................</td>\n<td>2.79</td>\n</tr>\n<tr>\n<td>INQREF ....................................</td>\n<td>2.80</td>\n</tr>\n<tr>\n<td>INQSCCL ....................................</td>\n<td>2.81</td>\n</tr>\n<tr>\n<td>INQSCPL ....................................</td>\n<td>2.82</td>\n</tr>\n<tr>\n<td>INQSUB ....................................</td>\n<td>2.83</td>\n</tr>\n<tr>\n<td>INQTEN ....................................</td>\n<td>2.84</td>\n</tr>\n<tr>\n<td>INQTXT ....................................</td>\n<td>2.85</td>\n</tr>\n<tr>\n<td>INQUIR ....................................</td>\n<td>2.86</td>\n</tr>\n<tr>\n<td>INRATG ....................................</td>\n<td>2.87</td>\n</tr>\n<tr>\n<td>INSPLG ....................................</td>\n<td>2.88</td>\n</tr>\n<tr>\n<td>INT4X4 ....................................</td>\n<td>2.89</td>\n</tr>\n<tr>\n<td>INTENG ....................................</td>\n<td>2.90</td>\n</tr>\n<tr>\n<td>INTHD2 ....................................</td>\n<td>2.91</td>\n</tr>\n<tr>\n<td>Command</td>\n<td>Page</td>\n</tr>\n<tr>\n<td>-----------</td>\n<td>------</td>\n</tr>\n<tr>\n<td>INTHID</td>\n<td>2.92</td>\n</tr>\n<tr>\n<td>INTLR</td>\n<td>2.93</td>\n</tr>\n<tr>\n<td>INTSHA</td>\n<td>2.94</td>\n</tr>\n<tr>\n<td>ITABLE</td>\n<td>2.95</td>\n</tr>\n<tr>\n<td>LCUC</td>\n<td>2.96</td>\n</tr>\n<tr>\n<td>LENTXT</td>\n<td>2.97</td>\n</tr>\n<tr>\n<td>LITSRC</td>\n<td>2.98</td>\n</tr>\n<tr>\n<td>LODCOL</td>\n<td>2.99</td>\n</tr>\n<tr>\n<td>MAPWV</td>\n<td>2.100</td>\n</tr>\n<tr>\n<td>MAXMIN</td>\n<td>2.101</td>\n</tr>\n<tr>\n<td>MODIFY</td>\n<td>2.102</td>\n</tr>\n<tr>\n<td>MOV4X4</td>\n<td>2.104</td>\n</tr>\n<tr>\n<td>MOVABS</td>\n<td>2.105</td>\n</tr>\n<tr>\n<td>MUL4X4</td>\n<td>2.106</td>\n</tr>\n<tr>\n<td>NEWGRP</td>\n<td>2.107</td>\n</tr>\n<tr>\n<td>NORMAL</td>\n<td>2.108</td>\n</tr>\n<tr>\n<td>NORMTM</td>\n<td>2.109</td>\n</tr>\n<tr>\n<td>NORVEC</td>\n<td>2.110</td>\n</tr>\n<tr>\n<td>NRMAVE</td>\n<td>2.111</td>\n</tr>\n<tr>\n<td>OPNFIL</td>\n<td>2.112</td>\n</tr>\n<tr>\n<td>OUTBOX</td>\n<td>2.113</td>\n</tr>\n<tr>\n<td>PCHECK</td>\n<td>2.114</td>\n</tr>\n<tr>\n<td>PERDST</td>\n<td>2.115</td>\n</tr>\n<tr>\n<td>PIPLIN</td>\n<td>2.116</td>\n</tr>\n<tr>\n<td>PIPSRC</td>\n<td>2.118</td>\n</tr>\n<tr>\n<td>POLFIL</td>\n<td>2.120</td>\n</tr>\n<tr>\n<td>POLSTA</td>\n<td>2.121</td>\n</tr>\n<tr>\n<td>POLYS</td>\n<td>2.122</td>\n</tr>\n<tr>\n<td>PORMAN</td>\n<td>2.123</td>\n</tr>\n<tr>\n<td>PROMPT</td>\n<td>2.124</td>\n</tr>\n<tr>\n<td>PRSPC</td>\n<td>2.125</td>\n</tr>\n<tr>\n<td>PRSSTF</td>\n<td>2.126</td>\n</tr>\n<tr>\n<td>PURGE</td>\n<td>2.127</td>\n</tr>\n<tr>\n<td>PVEC</td>\n<td>2.128</td>\n</tr>\n<tr>\n<td>RDINIT</td>\n<td>2.129</td>\n</tr>\n<tr>\n<td>READMV</td>\n<td>2.130</td>\n</tr>\n<tr>\n<td>REDCHK</td>\n<td>2.131</td>\n</tr>\n<tr>\n<td>RESET</td>\n<td>2.132</td>\n</tr>\n<tr>\n<td>ROTATE</td>\n<td>2.133</td>\n</tr>\n<tr>\n<td>RPLCOP</td>\n<td>2.134</td>\n</tr>\n<tr>\n<td>RPLGLB</td>\n<td>2.135</td>\n</tr>\n<tr>\n<td>RUNANI</td>\n<td>2.136</td>\n</tr>\n<tr>\n<td>SAVTXT</td>\n<td>2.137</td>\n</tr>\n<tr>\n<td>SCALE</td>\n<td>2.138</td>\n</tr>\n<tr>\n<td>SETBGC</td>\n<td>2.139</td>\n</tr>\n</tbody>\n</table>\n\nALPHABETIZED LIST\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SETBOX</td>\n<td>2.140</td>\n</tr>\n<tr>\n<td>SETCLP</td>\n<td>2.141</td>\n</tr>\n<tr>\n<td>SETCNT</td>\n<td>2.142</td>\n</tr>\n<tr>\n<td>SETCOL</td>\n<td>2.143</td>\n</tr>\n<tr>\n<td>SETCON</td>\n<td>2.144</td>\n</tr>\n<tr>\n<td>SETDEF</td>\n<td>2.145</td>\n</tr>\n<tr>\n<td>SETDSP</td>\n<td>2.146</td>\n</tr>\n<tr>\n<td>SETDST</td>\n<td>2.147</td>\n</tr>\n<tr>\n<td>SETFLG</td>\n<td>2.148</td>\n</tr>\n<tr>\n<td>SETFNC</td>\n<td>2.149</td>\n</tr>\n<tr>\n<td>SETFOG</td>\n<td>2.150</td>\n</tr>\n<tr>\n<td>SETFRN</td>\n<td>2.151</td>\n</tr>\n<tr>\n<td>SETGLB</td>\n<td>2.152</td>\n</tr>\n<tr>\n<td>SETLIN</td>\n<td>2.153</td>\n</tr>\n<tr>\n<td>SETLUT</td>\n<td>2.154</td>\n</tr>\n<tr>\n<td>SETMOD</td>\n<td>2.155</td>\n</tr>\n<tr>\n<td>SETPER</td>\n<td>2.156</td>\n</tr>\n<tr>\n<td>SETPRT</td>\n<td>2.157</td>\n</tr>\n<tr>\n<td>SETRAT</td>\n<td>2.158</td>\n</tr>\n<tr>\n<td>SETREF</td>\n<td>2.159</td>\n</tr>\n<tr>\n<td>SETSCL</td>\n<td>2.160</td>\n</tr>\n<tr>\n<td>SETSCN</td>\n<td>2.161</td>\n</tr>\n<tr>\n<td>SETSPL</td>\n<td>2.162</td>\n</tr>\n<tr>\n<td>SETSTD</td>\n<td>2.163</td>\n</tr>\n<tr>\n<td>SETSUB</td>\n<td>2.164</td>\n</tr>\n<tr>\n<td>SETTEN</td>\n<td>2.165</td>\n</tr>\n<tr>\n<td>SETWND</td>\n<td>2.166</td>\n</tr>\n<tr>\n<td>SHRINK</td>\n<td>2.167</td>\n</tr>\n<tr>\n<td>SMOCLR</td>\n<td>2.168</td>\n</tr>\n<tr>\n<td>SMOGET</td>\n<td>2.169</td>\n</tr>\n<tr>\n<td>SMOSTR</td>\n<td>2.170</td>\n</tr>\n<tr>\n<td>STCONG</td>\n<td>2.171</td>\n</tr>\n<tr>\n<td>STOREL</td>\n<td>2.172</td>\n</tr>\n<tr>\n<td>STRATG</td>\n<td>2.173</td>\n</tr>\n<tr>\n<td>STSPALG</td>\n<td>2.174</td>\n</tr>\n<tr>\n<td>STTENG</td>\n<td>2.175</td>\n</tr>\n<tr>\n<td>SUMMARY</td>\n<td>2.176</td>\n</tr>\n<tr>\n<td>TEXT</td>\n<td>2.177</td>\n</tr>\n<tr>\n<td>TMPTS</td>\n<td>2.179</td>\n</tr>\n<tr>\n<td>TMPTSN</td>\n<td>2.180</td>\n</tr>\n<tr>\n<td>TRAVRS</td>\n<td>2.181</td>\n</tr>\n<tr>\n<td>TXTDIS</td>\n<td>2.183</td>\n</tr>\n<tr>\n<td>TXTINT</td>\n<td>2.184</td>\n</tr>\n<tr>\n<td>WARPOL</td>\n<td>2.185</td>\n</tr>\n<tr>\n<td>Command</td>\n<td>Page</td>\n</tr>\n<tr>\n<td>----------</td>\n<td>------</td>\n</tr>\n<tr>\n<td>WRITMV</td>\n<td>2.186</td>\n</tr>\n<tr>\n<td>WRTCHK</td>\n<td>2.187</td>\n</tr>\n<tr>\n<td>WRTDRV</td>\n<td>2.188</td>\n</tr>\n<tr>\n<td>WRTGEO</td>\n<td>2.189</td>\n</tr>\n<tr>\n<td>ZPLSTA</td>\n<td>2.190</td>\n</tr>\n</tbody>\n</table>\n# LIST OF ROUTINES BY FUNCTION\n\n## GROUPS AND ITEMS ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ACTGRP</td>\n<td>2.2</td>\n</tr>\n<tr>\n<td>ADDCAL</td>\n<td>2.3</td>\n</tr>\n<tr>\n<td>COPNUM</td>\n<td>2.21</td>\n</tr>\n<tr>\n<td>DEFAULT</td>\n<td>2.22</td>\n</tr>\n<tr>\n<td>DEFINE</td>\n<td>2.23</td>\n</tr>\n<tr>\n<td>DELETE</td>\n<td>2.24</td>\n</tr>\n<tr>\n<td>EXTCOP</td>\n<td>2.31</td>\n</tr>\n<tr>\n<td>GETAGR</td>\n<td>2.37</td>\n</tr>\n<tr>\n<td>GETCOP</td>\n<td>2.40</td>\n</tr>\n<tr>\n<td>GETDEF</td>\n<td>2.41</td>\n</tr>\n<tr>\n<td>GETGRU</td>\n<td></td>\n</tr>\n<tr>\n<td>GETITM</td>\n<td>2.42</td>\n</tr>\n<tr>\n<td>HUDITM</td>\n<td>2.43</td>\n</tr>\n<tr>\n<td>INITGI</td>\n<td>2.58</td>\n</tr>\n<tr>\n<td>INQUIR</td>\n<td>2.60</td>\n</tr>\n<tr>\n<td>MODIFY</td>\n<td>2.86</td>\n</tr>\n<tr>\n<td>NEWGRP</td>\n<td></td>\n</tr>\n<tr>\n<td>PURGE</td>\n<td>2.102</td>\n</tr>\n<tr>\n<td>RPLCOP</td>\n<td>2.107</td>\n</tr>\n<tr>\n<td>SUMMARY</td>\n<td>2.127</td>\n</tr>\n<tr>\n<td></td>\n<td>2.135</td>\n</tr>\n<tr>\n<td></td>\n<td>2.176</td>\n</tr>\n</tbody>\n</table>\n\n## ANIMATION ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ANFILI</td>\n<td>2.4</td>\n</tr>\n<tr>\n<td>ANFILS</td>\n<td>2.5</td>\n</tr>\n<tr>\n<td>ANIDRV</td>\n<td>2.6</td>\n</tr>\n<tr>\n<td>BEGANI</td>\n<td>2.10</td>\n</tr>\n<tr>\n<td>CAMERA</td>\n<td></td>\n</tr>\n<tr>\n<td>FNDFRM</td>\n<td>2.11</td>\n</tr>\n<tr>\n<td>GBACT</td>\n<td>2.32</td>\n</tr>\n<tr>\n<td>INCONG</td>\n<td>2.48</td>\n</tr>\n<tr>\n<td>INQCON</td>\n<td>2.59</td>\n</tr>\n<tr>\n<td>INQFRM</td>\n<td></td>\n</tr>\n<tr>\n<td>INQRAT</td>\n<td>2.64</td>\n</tr>\n<tr>\n<td>INQSPL</td>\n<td>2.71</td>\n</tr>\n<tr>\n<td>INQSPLG</td>\n<td>2.79</td>\n</tr>\n<tr>\n<td>INQSUB</td>\n<td>2.82</td>\n</tr>\n<tr>\n<td>INQTEG</td>\n<td>2.83</td>\n</tr>\n<tr>\n<td>INRATG</td>\n<td>2.84</td>\n</tr>\n<tr>\n<td>INSPLG</td>\n<td>2.87</td>\n</tr>\n<tr>\n<td></td>\n<td>2.88</td>\n</tr>\n</tbody>\n</table>\n### ANIMATION ROUTINES (cont.)\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>INTENG</td>\n<td>2.90</td>\n</tr>\n<tr>\n<td>RUNANI</td>\n<td>2.136</td>\n</tr>\n<tr>\n<td>SETCON</td>\n<td>2.144</td>\n</tr>\n<tr>\n<td>SETRAT</td>\n<td>2.158</td>\n</tr>\n<tr>\n<td>SETSPL</td>\n<td>2.162</td>\n</tr>\n<tr>\n<td>SETSUB</td>\n<td>2.164</td>\n</tr>\n<tr>\n<td>SETTEN</td>\n<td>2.165</td>\n</tr>\n<tr>\n<td>STCONG</td>\n<td>2.171</td>\n</tr>\n<tr>\n<td>STRATG</td>\n<td>2.173</td>\n</tr>\n<tr>\n<td>STSPLG</td>\n<td>2.175</td>\n</tr>\n<tr>\n<td>STTENG</td>\n<td>2.176</td>\n</tr>\n</tbody>\n</table>\n\n### DISPLAY DEVICE ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>COLERR</td>\n<td>2.19</td>\n</tr>\n<tr>\n<td>DISTXT</td>\n<td>2.26</td>\n</tr>\n<tr>\n<td>DRWABS</td>\n<td>2.28</td>\n</tr>\n<tr>\n<td>ERASE</td>\n<td>2.30</td>\n</tr>\n<tr>\n<td>INQDEV</td>\n<td>2.65</td>\n</tr>\n<tr>\n<td>ITABLE</td>\n<td>2.95</td>\n</tr>\n<tr>\n<td>MOVABS</td>\n<td>2.105</td>\n</tr>\n<tr>\n<td>POLFIL</td>\n<td>2.120</td>\n</tr>\n<tr>\n<td>RDINIT</td>\n<td>2.129</td>\n</tr>\n<tr>\n<td>SETCOL</td>\n<td>2.143</td>\n</tr>\n<tr>\n<td>SETLN</td>\n<td>2.153</td>\n</tr>\n<tr>\n<td>SETLUT</td>\n<td>2.154</td>\n</tr>\n<tr>\n<td>SETMOD</td>\n<td>2.155</td>\n</tr>\n<tr>\n<td>SETSCN</td>\n<td>2.161</td>\n</tr>\n</tbody>\n</table>\n\n### TRANSFORMATION ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ATFROM</td>\n<td>2.8</td>\n</tr>\n<tr>\n<td>AUTOON</td>\n<td>2.9</td>\n</tr>\n<tr>\n<td>CENTER</td>\n<td>2.12</td>\n</tr>\n<tr>\n<td>FOURVW</td>\n<td>2.33</td>\n</tr>\n<tr>\n<td>GETWND</td>\n<td>2.46</td>\n</tr>\n<tr>\n<td>GTUROX</td>\n<td>2.52</td>\n</tr>\n<tr>\n<td>GTUROY</td>\n<td>2.54</td>\n</tr>\n<tr>\n<td>GTUROZ</td>\n<td>2.55</td>\n</tr>\n<tr>\n<td>GTUSCL</td>\n<td>2.56</td>\n</tr>\n<tr>\n<td>GTUTRN</td>\n<td>2.57</td>\n</tr>\n<tr>\n<td>INQDST</td>\n<td>2.68</td>\n</tr>\n<tr>\n<td>INQGLB</td>\n<td>2.73</td>\n</tr>\n</tbody>\n</table>\nTRANSFORMATION ROUTINES (cont.)\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>INQLAF</td>\n<td></td>\n</tr>\n<tr>\n<td>INQPER</td>\n<td></td>\n</tr>\n<tr>\n<td>INQPRT</td>\n<td></td>\n</tr>\n<tr>\n<td>INQSCL</td>\n<td></td>\n</tr>\n<tr>\n<td>INT4X4</td>\n<td></td>\n</tr>\n<tr>\n<td>MAPWV</td>\n<td></td>\n</tr>\n<tr>\n<td>MOV4X4</td>\n<td></td>\n</tr>\n<tr>\n<td>MUL4X4</td>\n<td></td>\n</tr>\n<tr>\n<td>PERDST</td>\n<td></td>\n</tr>\n<tr>\n<td>PORMAN</td>\n<td></td>\n</tr>\n<tr>\n<td>PRSPC</td>\n<td></td>\n</tr>\n<tr>\n<td>PRSSTF</td>\n<td></td>\n</tr>\n<tr>\n<td>RESET</td>\n<td></td>\n</tr>\n<tr>\n<td>ROTATE</td>\n<td></td>\n</tr>\n<tr>\n<td>RPLGLB</td>\n<td></td>\n</tr>\n<tr>\n<td>SCALE</td>\n<td></td>\n</tr>\n<tr>\n<td>SETDST</td>\n<td></td>\n</tr>\n<tr>\n<td>SETGLB</td>\n<td></td>\n</tr>\n<tr>\n<td>SETPER</td>\n<td></td>\n</tr>\n<tr>\n<td>SETPRT</td>\n<td></td>\n</tr>\n<tr>\n<td>SETSCL</td>\n<td></td>\n</tr>\n<tr>\n<td>SETWND</td>\n<td></td>\n</tr>\n<tr>\n<td>SHRINK</td>\n<td></td>\n</tr>\n<tr>\n<td>TMPTS</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>TEXT</td>\n<td></td>\n</tr>\n<tr>\n<td>CHRNUM</td>\n<td></td>\n</tr>\n<tr>\n<td>GENTXT</td>\n<td></td>\n</tr>\n<tr>\n<td>INQTXT</td>\n<td></td>\n</tr>\n<tr>\n<td>SAVTXT</td>\n<td></td>\n</tr>\n<tr>\n<td>TXTDIS</td>\n<td></td>\n</tr>\n<tr>\n<td>TXTINT</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nTEXT ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AROCLR</td>\n<td></td>\n</tr>\n<tr>\n<td>CNTBAR</td>\n<td></td>\n</tr>\n<tr>\n<td>FRINGE</td>\n<td></td>\n</tr>\n<tr>\n<td>FRNBAR</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nVECTOR AND SCALAR FUNCTION ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AROCLR</td>\n<td></td>\n</tr>\n<tr>\n<td>CNTBAR</td>\n<td></td>\n</tr>\n<tr>\n<td>FRINGE</td>\n<td></td>\n</tr>\n<tr>\n<td>FRNBAR</td>\n<td></td>\n</tr>\n<tr>\n<td>VECTOR AND SCALAR FUNCTION ROUTINES (cont.)</td>\n<td></td>\n</tr>\n<tr>\n<td>------------------------------------------</td>\n<td></td>\n</tr>\n<tr>\n<td>INQCNT</td>\n<td>2.63</td>\n</tr>\n<tr>\n<td>INQDSP</td>\n<td>2.66</td>\n</tr>\n<tr>\n<td>INQFNC</td>\n<td>2.69</td>\n</tr>\n<tr>\n<td>INQFRN</td>\n<td>2.72</td>\n</tr>\n<tr>\n<td>INQLEV</td>\n<td>2.75</td>\n</tr>\n<tr>\n<td>INQREF</td>\n<td>2.80</td>\n</tr>\n<tr>\n<td>PVEC</td>\n<td>2.128</td>\n</tr>\n<tr>\n<td>SETCNT</td>\n<td>2.142</td>\n</tr>\n<tr>\n<td>SETDSP</td>\n<td>2.146</td>\n</tr>\n<tr>\n<td>SETFNC</td>\n<td>2.149</td>\n</tr>\n<tr>\n<td>SETFRN</td>\n<td>2.151</td>\n</tr>\n<tr>\n<td>SETREF</td>\n<td>2.159</td>\n</tr>\n<tr>\n<td>SETSTD</td>\n<td>2.163</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>INPUT/OUTPUT ROUTINES</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>GETCOM</td>\n</tr>\n<tr>\n<td>GETNUM</td>\n</tr>\n<tr>\n<td>GETXT</td>\n</tr>\n<tr>\n<td>LCUC</td>\n</tr>\n<tr>\n<td>LENTXT</td>\n</tr>\n<tr>\n<td>OPNFIL</td>\n</tr>\n<tr>\n<td>PROMPT</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>RASTER ROUTINES</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>COLORS</td>\n</tr>\n<tr>\n<td>DODITH</td>\n</tr>\n<tr>\n<td>HIDSUR</td>\n</tr>\n<tr>\n<td>INQFOG</td>\n</tr>\n<tr>\n<td>INQLIT</td>\n</tr>\n<tr>\n<td>INTHD2</td>\n</tr>\n<tr>\n<td>INTHID</td>\n</tr>\n<tr>\n<td>INTSHA</td>\n</tr>\n<tr>\n<td>LITSRC</td>\n</tr>\n<tr>\n<td>PCHECK</td>\n</tr>\n<tr>\n<td>PIPSRC</td>\n</tr>\n<tr>\n<td>SETFOG</td>\n</tr>\n<tr>\n<td>WARPOL</td>\n</tr>\n</tbody>\n</table>\n\nLIST BY FUNCTION xi\n## HIDDEN LINE REMOVAL ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>HIDLIN</td>\n<td>2.56</td>\n</tr>\n<tr>\n<td>INTHLR</td>\n<td>2.93</td>\n</tr>\n<tr>\n<td>LODCOL</td>\n<td>2.99</td>\n</tr>\n<tr>\n<td>STOREL</td>\n<td>2.172</td>\n</tr>\n</tbody>\n</table>\n\n## NORMAL CREATION AND MANIPULATION ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>NORMAL</td>\n<td>2.108</td>\n</tr>\n<tr>\n<td>NORMTM</td>\n<td>2.109</td>\n</tr>\n<tr>\n<td>NORVEC</td>\n<td>2.110</td>\n</tr>\n<tr>\n<td>NRMAVE</td>\n<td>2.111</td>\n</tr>\n<tr>\n<td>SMOCLR</td>\n<td>2.163</td>\n</tr>\n<tr>\n<td>SMOGET</td>\n<td>2.169</td>\n</tr>\n<tr>\n<td>SMOSTR</td>\n<td>2.170</td>\n</tr>\n<tr>\n<td>TMPTSN</td>\n<td>2.180</td>\n</tr>\n</tbody>\n</table>\n\n## CLIPPING ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CLPLIN</td>\n<td>2.14</td>\n</tr>\n<tr>\n<td>CLPPOL</td>\n<td>2.15</td>\n</tr>\n<tr>\n<td>CLPPZPE</td>\n<td>2.16</td>\n</tr>\n<tr>\n<td>GETCLLP</td>\n<td>2.38</td>\n</tr>\n<tr>\n<td>POLSTA</td>\n<td>2.121</td>\n</tr>\n<tr>\n<td>SETCLLP</td>\n<td>2.141</td>\n</tr>\n<tr>\n<td>ZPLSTA</td>\n<td>2.190</td>\n</tr>\n</tbody>\n</table>\n\n## INPUT/OUTPUT FILE ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>READMV</td>\n<td>2.130</td>\n</tr>\n<tr>\n<td>REDCHK</td>\n<td>2.131</td>\n</tr>\n<tr>\n<td>WRITMV</td>\n<td>2.186</td>\n</tr>\n<tr>\n<td>WRTCHK</td>\n<td>2.187</td>\n</tr>\n<tr>\n<td>WRTDRV</td>\n<td>2.189</td>\n</tr>\n<tr>\n<td>WRTGEO</td>\n<td>2.190</td>\n</tr>\n</tbody>\n</table>\n\n## INITIALIZATION ROUTINE (MUST BE INCLUDED IN ALL USER APPLICATIONS)\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>GRAINT</td>\n<td>2.50</td>\n</tr>\n</tbody>\n</table>\n\n## OTHER ROUTINES\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CNTRPT</td>\n<td>2.18</td>\n</tr>\n<tr>\n<td>DISALL</td>\n<td>2.19</td>\n</tr>\n<tr>\n<td>DRWBOR</td>\n<td>2.29</td>\n</tr>\n<tr>\n<td>GETLIM</td>\n<td>2.44</td>\n</tr>\n<tr>\n<td>GLBAXS</td>\n<td>2.49</td>\n</tr>\n</tbody>\n</table>\nOTHER ROUTINES (cont.)\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>INQBGC</td>\n<td>2.61</td>\n</tr>\n<tr>\n<td>INQBOX</td>\n<td>2.62</td>\n</tr>\n<tr>\n<td>INQFLG</td>\n<td>2.67</td>\n</tr>\n<tr>\n<td>MAXMIN</td>\n<td>2.100</td>\n</tr>\n<tr>\n<td>OUTBOX</td>\n<td>2.113</td>\n</tr>\n<tr>\n<td>PIPLIN</td>\n<td>2.116</td>\n</tr>\n<tr>\n<td>POLYS</td>\n<td>2.122</td>\n</tr>\n<tr>\n<td>SETBGC</td>\n<td>2.139</td>\n</tr>\n<tr>\n<td>SETBOX</td>\n<td>2.140</td>\n</tr>\n<tr>\n<td>SETDEF</td>\n<td>2.145</td>\n</tr>\n<tr>\n<td>SETFLG</td>\n<td>2.148</td>\n</tr>\n<tr>\n<td>TRAVRS</td>\n<td>2.181</td>\n</tr>\n</tbody>\n</table>\n\nLIST BY FUNCTION xiii\nIntroduction\n\nTHE RASTER GRAPHICS DISPLAY LIBRARY\n\nRaster Display Systems\n\nWhen you use computer graphics to see complex three-dimensional data, your accuracy and productivity increase. Raster display systems show trends and patterns much more clearly than volumes of tabulated data because color and shading can be used to depict realistic scenes.\n\nIn engineering applications, color and shading may be used not only to realistically portray an object, but to present additional information. Distorted shapes and color coding of functions include failure criteria, stress or strain components, temperature, and pressure.\n\nA Common Problem of Raster Display Systems\n\nMany applications lack adequate presentation graphics. You may not have a set of software tools that allow you to generate quickly the raster image capabilities you need. Or the algorithms you want may be incorporated in commercial packages or proprietary codes, or be unavailable outside a specialized university environment. What you need is a raster display system that allows you to display the graphics you want.\n\nThe Raster Graphics Display Library\n\nThe Raster Graphics Display Library (RGDL) is a high level subroutine package that gives you the advanced raster graphics display capabilities you need. RGDL uses FORTRAN source code routines to build subroutines modular enough to use as stand-alone routines in a black box type of environment. With RGDL, you have a set of tools that are easily used, well documented, and error tolerant.\n\nHow To Use This Manual\n\nThis documentation is divided into four chapters and three appendices. The first chapter contains six examples you should go through if you want to learn how to use RGDL in the fastest, most complete way possible. Chapter two contains a technical reference section, chapter three a common block reference section, and chapter four a reference on include files.\n\nThe first appendix, a link map, contains information from MOVIE.BYU software and documentation. MOVIE.BYU is a general purpose computer graphics display system that uses RGDL software.\n\nAppendix B is a section about hierarchical data structures. The third appendix contains installation information and our address.\nIf you want more information about each section, go to the next page or to the chapter introductions. If you want to make sure the contents on the magnetic tape you received are complete, go to page C.1. For installation information and our address, see page C.2.\nCHAPTER SUMMARIES\n\nChapter 1 EXAMPLE PROBLEMS\n\nThe display library will be introduced to you using six example problems. When you compile and link these examples, you will get an understanding for what you can achieve using the library routines. Each example builds on the previous problem and gets more complicated from one example to the next.\n\nYou won't need to type in the example problems, because they are supplied with the software. Make sure you compile and link applications with the proper system flags set. Applications may become very large and some systems require special compiler and link options.\n\nChapter 2 TECHNICAL REFERENCES\n\nChapter three contains routines within the display library that you will call to produce raster graphics. The routines are in alphabetical order, each on a separate page. Each user-callable routine is described by function and calling parameters.\n\nChapter three does not contain a description of all routines in the display library, but rather only those routines that could be called by an applications program.\n\nChapter 3 COMMON BLOCK REFERENCES\n\nChapter four contains a common block reference. The chapter lists all common blocks that are used in the display library, and discusses the use of each variable within each common block.\n\nChapter 4 INCLUDE FILE REFERENCES\n\nChapter five contains a reference on the include files that are necessary to compile the display library. Each include file and its purpose are listed.\n\nAppendix A LINK MAP\n\nThis appendix contains the link map for MOVIE.BYU version 6. MOVIE.BYU is a general purpose computer graphics display system that uses RGDL software. It uses the display library in addition to other routines, and is an excellent source as an auxiliary reference.\n\nThe link map is included to show you the amount of code that may be necessary to perform a function. The link map will also help if you don't have library utilities.\nAppendix B AN INTRODUCTION TO HIERARCHICAL DATA STRUCTURES\n\nAppendix B contains a section about creating new groups. The section will help you understand the hierarchial data structures used in RGDL. You are asked to create new groups in Examples Five and Six of Chapter One.\n\nAppendix C SOFTWARE INSTALLATION\n\nAppendix C contains installation information. It also gives you the address and phone number of the people you can contact if you find bugs or problems in RGDL software.\nChapter 1\n\nEXAMPLE PROBLEMS\n\nThis chapter contains example drivers for the Raster Graphics Subroutine Library. The examples call routines described in chapter two, Technical References. You will learn how to create applications programs that use the graphics library routines. By going through the examples, you will also become familiar with many of the system's capabilities.\n\nWhy should you go through the examples?\n\nBecause you will save time and headaches. The examples are not busywork. They are six exercises that build on each other to teach you how the Raster Graphics Subroutine Library works.\n\nYou should study the examples carefully, then actually compile, link, and run them. You won't need to type them in because they are supplied on tape with the rest of the software.\n\nThings you should know\n\nMake sure you compile and link applications with the correct system flags set. The applications may become very large and some systems require special compiler and link options.\n\nAll examples are read in a hard-coded geometry file, EXP9.GEO. A common data base is used so you can follow along with the example problems through more complex operations. Of course, in most cases, you will want to create drivers that prompt for the geometry file names to be read into the data base.\n\nThe examples shown do not perform error checking. We strongly suggest you include error checking in applications you write.\n\nAbout the display device and host computer\n\nThe examples will be most useful to you when they are run on a raster display device that allows for screen overlays, such as the Tektronix 4115.\n\nBecause no link maps are shown in the examples, the host computer you use should have a library utility. If the host computer does not have a library utility, refer to the link map in the appendix to see what routines must be linked with the drivers.\n\nAfter the first example, all new additions to the next five exercises are shown in bold.\nEXAMPLE 1\n\nPROGRAM RSPEX1\n\nRASTER GRAPHICS SUBROUTINE PACKAGE EXAMPLE 1\n\nTHIS EXAMPLE PROBLEM WILL READ IN A GEOMETRY FILE AND\nDISPLAY IT IN LINE DRAWING MODE WITH ALL DEFAULTS.\n\nTHIS CALL IS NEEDED IN ALL PROGRAMS. IT INITIALIZES THE\nGRAPHICS PACKAGE.\n\nCALL GRAINT\n\nREAD IN A MOVIE.BYU GEOMETRY FILE CALLED EXP9.GEO. DO NOT READ IN\nA FUNCTION OR A DISPLACEMENT FILE.\n\nCALL READMV('EXP9.GEO',' ',' ')\n\nDISPLAY LINE DRAWING PICTURE\n\nCALL DISALL\nSTOP\nEND\nEXAMPLE 2\n\nPROGRAM RSPEX2\n\nRASTER GRAPHICS SUBROUTINE PACKAGE EXAMPLE 2\n\nTHIS EXAMPLE PROBLEM ADDS A USER DEFINED LOOK FROM VECTOR TO\nEXAMPLE PROBLEM 1\n\nREAL LOOKAT(3), LOOKFR(3)\n\nTHIS SECTION IS NEEDED IN ALL PROGRAMS. IT INITIALIZES THE\nGRAPHICS PACKAGE.\n\nCALL GRAINT\n\nREAD IN A MOVIE.BYU GEOMETRY FILE CALLED EXP9.GEO. DO NOT READ IN\nA FUNCTION OR A DISPLACEMENT FILE.\n\nCALL READMV('EXP9.GEO', '. ', '. ')\n\nPROMPT FOR LOOK FROM VECTOR. SET THE LOOK AT POINT TO ZERO, AND\nCALL THE ROUTINE TO SET UP THE LOOK AT/FROM TRANSFORMATION.\n\nWRITE(*,*), 'ENTER LOOK-FROM VECTOR (X,Y,Z)'\nREAD(*,*) LOOKFR(1), LOOKFR(2), LOOKFR(3)\nLOOKAT(1) = 0.\nLOOKAT(2) = 0.\nLOOKAT(3) = 0.\nCALL ATFROM(LOOKAT, LOOKFR)\n\nCOULD ALSO DO THE ATFROM CALL BE GOING THROUGH GLBACT, THIS CALL\nWOULD LOOK LIKE:\n\nCALL GLBACT('FRM', LOOKAT(1), LOOKAT(2), LOOKAT(3), LOOKFR(1),\n&\n'LOOKFR(2), LOOKFR(3))\n\nGLBACT SHOULD BE USED IF A USER IS RUNNING ANIMATION, SINCE THIS\nROUTINE WILL CAPTURE THE LOOK AT/FROM COMMAND AS A MOVEMENT THAT\nNEEDS TO BE ANIMATED.\n\nDISPLAY LINE DRAWING OF PICTURE\n\nCALL DISALL\nSTOP\nEND\n\nChapter One EXAMPLE PROBLEMS 1.3\nEXAMPLE 3\n\nPROGRAM RSPEX3\n\nRASTER GRAPHICS SUBROUTINE PACKAGE EXAMPLE 3\n\nTHIS EXAMPLE PROBLEM USES THE I/O ROUTINES FOR ALL\nPROMPTS AND USER INPUT. ALSO ADDED IS A USER DEFINED\nROTATION AND TRANSLATION OF PART I. THE PICTURE IS\nDISPLAYED IN LINE DRAWING MODE.\n\nCHARACTER*(73) TEXT\nCHARACTER*80 FORM\nDIMENSION XNUM(40), VALUE(6)\nREAL LOOKAT(3), LOOKFR(3)\n\nTHIS SECTION IS NEEDED IN ALL PROGRAMS. IT INITIALIZES THE\nGRAPHICS PACKAGE.\n\nCALL GRAINT\n\nREAD IN A MOVIE.BYU GEOMETRY FILE CALLED EXP9.GEO. DO NOT READ IN\nA FUNCTION OR A DISPLACEMENT FILE.\n\nCALL READMV('EXP9.GEO',' ',' ')\n\nPROMPT FOR LOOK FROM VECTOR. SET THE LOOK AT POINT TO ZERO, AND\nCALL THE ROUTINE TO SET UP THE LOOK AT/FROM TRANSFORMATION.\nPERFORM AN INTERNAL READ FOR THE PROMPT. CALL GETXT WITH THE\nPROMPT, WHICH WILL RETURN THE TEXT STRING RESPONSE FROM THE USER -\nTEXT, AND THE NUMBER OF CHARACTERS IN TEXT - NCHAR. NEXT, CALL\nGETNUM WHICH WILL PARSE THE USER TEXT STRING FOR NUMBERS. XNUM\nWILL BE AN ARRAY OF NUMBERS, AND K2 IS THE NUMBER OF NUMBERS\nFOUND.\n\nWRITE(FORM,100)'ENTER LOOK-FROM VECTOR (X,Y,Z)'\nCALL GETXT(TEXT,NCHAR,FORM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nLOOKAT(1) = 0\nLOOKAT(2) = 0\nLOOKAT(3) = 0\nIF(K2.EQ.0) THEN\n WRITE(FORM,100)'NO LOOK-FROM VECTOR SPECIFIED!'\n CALL PROMPT(FORM)\nELSE\n LOOKFR(1) = XNUM(1)\n LOOKFR(2) = XNUM(2)\n LOOKFR(3) = XNUM(3)\n CALL ATFROM (LOOKAT,LOOKFR)\nEND IF\nEXAMPLE 3\n\nPROMPT FOR AND PERFORM A ROTATION FOR PART 1\n\nWRITE(FORM,100) 'X,Y,Z ROTATION ANGLES (DEGREES) FOR PART 1?\n\nCALL GETXT(TEXT,NCHAR,FROM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nVALUE(1) = XNUM(1)\nVALUE(2) = XNUM(2)\nVALUE(3) = XNUM(3)\n\n'1' IS THE PART TO MODIFY.\n4 IS THE FLAG INDICATING ROTATION.\nVALUE IS AN ARRAY OF NUMBERS\nCORRESPONDING TO THE ACTION\nFLAG.\n\nCALL MODIFY('1',4,VALUE)\n\nPROMPT FOR AND PERFORM A TRANSLATION FOR PART 1.\n\nWRITE(FORM,100)'X,Y,Z TRANSLATION FOR PART 1\nCALL GETXT(TEXT,NCHAR,FROM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nVALUE(1) = XNUM(1)\nVALUE(2) = XNUM(2)\nVALUE(3) = XNUM(3)\n\nTHE ACTION FLAG 5 IS THE TRANSLATION FLAG\n\nCALL MODIFY('1',5,VALUE)\n\nDISPLAY LINE DRAWING OF PICTURE\n\nCALL DISALL\n\nChapter One EXAMPLE PROBLEMS 1.5\nEXAMPLE 4\n\nPROGRAM RSPEX4\n\nRASTER GRAPHICS SUBROUTINE PACKAGE EXAMPLE 4\n\nTHIS EXAMPLE PROBLEM TAKES EXAMPLE PROBLEM 3, AND DEFINES FOUR DIFFERENT VIEW PORTS. THE FIRST VIEW PORT IS DRAWN IN LINE DRAWING MODE, THE SECOND VIEW PORT IS DRAWN IN HIDDEN LINE MODE, THE THIRD VIEW PORT IS DRAWN IN SHADED IMAGE MODE. THE FOURTH VIEW PORT IS DRAWN IN SHADED IMAGE MODE WITH DITHERING.\n\nCHARACTER*(73) TEXT\nCHARACTER*80 FORM\nDIMENSION XNUM(40),VALUE(6)\nREAL LOOKAT(3), LOOKFR(3)\n\nTHIS SECTION IS NEEDED IN ALL PROGRAMS. IT INITIALIZES THE GRAPHICS PACKAGE.\n\nCALL GRAINT\n\nREAD IN A MOVIE.BYU GEOMETRY FILE CALLED EXP9.GEO. DO NOT READ IN A FUNCTION OR A DISPLACEMENT FILE.\n\nCALL READMV('EXP9.GEO',' ',' ')\n\nPROMPT FOR LOOK FROM VECTOR. SET THE LOOK AT POINT TO ZERO, AND CALL THE ROUTINE TO SET UP THE LOOK AT/FROM TRANSFORMATION. PERFORM AND INTERNAL READ FOR THE PROMPT. CALL GETXT WITH THE PROMPT, WHICH WILL RETURN THE TEXT STRING RESPONSE FROM THE USER-TEST, AND THE NUMBER OF CHARACTERS IN TEXT-NCHAR. NEXT, CALL GETNUM WHICH WILL PARSE THE USER TEXT STRING FOR NUMBERS. XNUM WILL BE AN ARRAY OF NUMBERS, AND K2 IS THE NUMBER OF NUMBERS FOUND.\n\nWRITE(FORM,100) 'ENTER LOOK-FROM VECTOR (X,Y,Z)' CALL GETXT(TEXT,NCHAR,FORM) CALL GETNUM(TEXT,NCHAR,XNUM,K2) LOOKAT(1) = 0. LOOKAT(2) = 0. LOOKAT(3) = 0. IF(K2 .EQ. 0) THEN WRITE(FORM,100) 'NO LOOK-FROM VECTOR SPECIFIED!' CALL PROMPT(FORM) ELSE LOOKFR(1) = XNUM(1) LOOKFR(2) = XNUM(2) LOOKFR(3) = XNUM(3) CALL ATFROM(LOOKAT,LOOKFR) END IF\nEXAMPLE 4\n\nPROMPT FOR AND PERFORM A ROTATION FOR PART 1\n\nWRITE(FORM,100) 'X,Y,Z ROTATION ANGLES (DEGREES) FOR PART 1?'\nCALL GETXT(TEXT,NCHAR,FORM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nVALUE(1) = XNUM(1)\nVALUE(2) = XNUM(2)\nVALUE(3) = XNUM(3)\nCALL MODIFY('1',4,VALUE)\n\nPROMPT FOR AND PERFORM A TRANSLATE FOR PART 1\n\nWRITE(FORM,100) 'X,Y,Z TRANSLATION FOR PART 1?'\nCALL GETXT(TEXT,NCHAR,FORM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nVALUE(1) = XNUM(1)\nVALUE(2) = XNUM(2)\nVALUE(3) = XNUM(3)\nCALL MODIFY('1',5,VALUE)\n\nSET THE VIEWPORT TO THE UPPER LEFT QUARTER OF THE SCREEN\n\nCALL SETPRT(0.,.5,.75)\n\nDISPLAY LINE DRAWING OF PICTURE\n\nCALL DISALL\n\nSET THE VIEWPORT TO THE UPPER RIGHT QUARTER OF THE SCREEN\n\nCALL SETPRT(.5,1.,.75)\n\nSET THE HIDDEN LINE FLAG ON AND DISPLAY THE PICTURE\n\nCALL SETFLG('HIDDEN', .TRUE.)\nCALL DISALL\n\nSET THE VIEWPORT TO THE LOWER LEFT QUARTER OF THE SCREEN\n\nCALL SETPRT(0.,.5,.25)\n\nSET THE SHADED IMAGE FLAG AND DISPLAY THE PICTURE\n\nCALL SETFLG('SHADED', .TRUE.)\nCALL DISALL\n\nSET THE VIEWPORT TO THE LOWER RIGHT QUARTER OF THE SCREEN\n\nCALL SETPRT(.5,1.,.25)\n\nSET THE DITHERING FLAG ON, AND DISPLAY THE RASTER IMAGE OVER\nCALL SETFLG('DITHER', .TRUE.)\nCALL DISALL\n\n100 FORMAT(A)\n STOP\n END\nEXAMPLE 5\n\nPROGRAM RSPEX5\n\nRASTER GRAPHICS SUBROUTINE PACKAGE EXAMPLE 5\n\nTHIS EXAMPLE PROBLEM TAKES EXAMPLE PROBLEM 4 AND MODIFIES IT\nBY CREATING A NEW GROUP. THE COLOR AND SHADING OF PART 1 IS SET,\nAND THE COLOR OF THE HIGHER GROUP IS SET TO GREEN. THE UPPER\nRIGHT VIEWPORT IS SHOWN IN FOUR VIEW MODE.\n\nCHARACTER*(73) TEXT\nCHARACTER*80 FORM\nDIMENSION XNUM(40),VALUE(6)\nREAL LOOKAT(3), LOOKFR(3)\n\nTHIS SECTION IS NEEDED IN ALL PROGRAMS. IT INITIALIZES THE\nGRAPHICS PACKAGE.\n\nCALL GRAINT\n\nREAD IN A MOVIE.BYU GEOMETRY FILE CALLED EXP9.GEO. DO NOT READ IN\nA FUNCTION OR A DISPLACEMENT FILE.\n\nCALL READMV('EXP9.GEO',' ', ' ', ' ')\n\nPROMPT FOR LOOK FROM VECTOR. SET THE LOOK AT POINT TO ZERO, AND\nCALL THE ROUTINE TO SET UP THE LOOK AT/FROM TRANSFORMATION.\nPERFORM AND INTERNAL READ FOR THE PROMPT. CALL GETXT WITH THE\nPROMPT, WHICH WILL RETURN THE TEXT STRING RESPONSE FROM THE USER -\nTEST, AND THE NUMBER OF CHARACTERS IN TEXT - NCHAR. NEXT, CALL\nGETNUM WHICH WILL PARSE THE USER TEXT STRING FOR NUMBERS. XNUM\nWILL BE AN ARRAY OF NUMBERS, AND K2 IS THE NUMBER OF NUMBERS\nFOUND.\n\nWRITE(FORM,100) 'ENTER LOOK-FROM VECTOR (X,Y,Z)' \nCALL GETXT(TEXT,NCHAR,FOM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nLOOKAT(1) = 0.\nLOOKAT(2) = 0.\nLOOKAT(3) = 0.\nIF(K2 .EQ. 0) THEN\n WRITE(FORM,100) 'NO LOOK-FROM VECTOR SPECIFIED!' \n CALL PROMPT(FORM)\nELSE\n LOOKFR(1) = XNUM(1)\n LOOKFR(2) = XNUM(2)\n LOOKFR(3) = XNUM(3)\n CALL ATFROM(LOOKAT,LOOKFR)\nEND IF\nEXAMPLE 5\n\nPROMPT FOR AND PERFORM A ROTATION FOR PART i\n\nWRITE(FORM,100) 'X,Y,Z ROTATION ANGLES (DEGREES) FOR PART i?'\n\nCALL GETXT(TEXT,NCHAR,FORM)\nCALL GETXT(TEXT,NCHAR,XNUM,K2)\nVALUE(1) = XNUM(1)\nVALUE(2) = XNUM(2)\nVALUE(3) = XNUM(3)\n\nCALL MODIFY('1',4,VALUE)\n\nPROMPT FOR AND PERFORM A TRANSLATE FOR PART i\n\nWRITE(FORM,100) 'X,Y,Z TRANSLATION FOR PART i?'\nCALL GETXT(TEXT,NCHAR,FORM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nVALUE(1) = XNUM(1)\nVALUE(2) = XNUM(2)\nVALUE(3) = XNUM(3)\nCALL MODIFY('1',5,VALUE)\n\nCREATE A NEW GROUP (SEE \"AN INTRODUCTION TO HIERARCHICAL DATA STRUCTURES\" IN APPENDIX B.)\n\nCALL DEFINE('TOP GROUP')\n\nCOPY THE GROUP \"ROOT\" INTO THE NEW GROUP AND CALL THE COPY \"COPY ROOT i\"\n\nCALL ADDCAL('ROOT','COPY ROOT i')\n\nSET THE COLOR OF THE NEW COPY TO GREEN, AND SET THE COLOR OF PART 1 (PART 1 IS REALLY COPY 1) TO RED. ALSO SET THE SHADING ATTRIBUTE OF COPY 1 TO SMOOTH\n\nVALUE(1) = 0.\nVALUE(2) = 1.\nVALUE(3) = 0.\nCALL MODIFY('COPY ROOT 1',8,VALUE)\nVALUE(1) = 1.\nVALUE(2) = 0.\nCALL MODIFY('1',8,VALUE)\nVALUE(1) = 2.\nCALL MODIFY('1',11,VALUE)\n\nSET THE VIEWPORT TO THE UPPER LEFT QUARTER OF THE SCREEN\n\nCALL SETPRT(0.,.5,.75)\n\nDISPLAY LINE DRAWING OF PICTURE\nCALL DISALL\n\nSET THE VIEWPORT TO THE UPPER RIGHT QUARTER OF THE SCREEN\nCALL SETPRT(.5, 1., .75)\n\nSET THE HIDDEN LINE FLAG ON AND DISPLAY THE PICTURE IN FOUR\nSTANDARD VIEWS\nCALL SETFLG('HIDDEN', .TRUE.)\nCALL FOURVW\n\nSET THE VIEWPORT TO THE LOWER LEFT QUARTER OF THE SCREEN\nCALL SETPRT(0., .5, .25)\n\nSET THE SHADED IMAGE FLAG AND DISPLAY THE PICTURE\nCALL SETFLG('SHADE', .TRUE.)\nCALL DISALL\n\nSET THE VIEWPORT TO THE LOWER RIGHT QUARTER OF THE SCREEN\nCALL SETPRT(.5, 1., .25)\n\nSET THE DITHERING FLAG ON, AND DISPLAY THE RASTER IMAGE OVER\nCALL SETFLG('DITHER', .TRUE.)\nCALL DISALL\n\n100 FORMAT(A)\nSTOP\nEND\nEXAMPLE 6\n\nPROGRAM RSPEX6\n\nRASTER GRAPHICS SUBROUTINE PACKAGE EXAMPLE 6\n\nTHIS EXAMPLE PROBLEM TAKES EXAMPLE PROBLEM 5 AND MODIFIES IT BY CREATING TWO COPIES OF THE ORIGINAL GEOMETRY FILE. THE USER IS PROMPTED FOR A TRANSLATE OF THE SECOND COPY.\n\nCHARACTER*(73) TEXT\nCHARACTER*80 FORM\nDIMENSION XNUM(40),VALUE(6)\nREAL LOOKAT(3), LOOKFOR(3)\n\nC--this section is needed in all programs. It initializes the graphics package.\nC\n\nCALL GRAINT\n\nREAD IN A MOVIE.BYU GEOMETRY FILE CALLED EXP9.GEO. DO NOT READ IN A FUNCTION OR A DISPLACEMENT FILE.\n\nCALL READMV('EXP9.GEO',''\n\nPROMPT FOR LOOK FROM VECTOR. SET THE LOOK AT POINT TO ZERO, AND CALL THE ROUTINE TO SET UP THE LOOK AT/FROM TRANSFORMATION. PERFORM AND INTERNAL READ FOR THE PROMPT. CALL GETXT WITH THE PROMPT, WHICH WILL RETURN THE TEXT STRING RESPONSE FROM THE USER - TEST, AND THE NUMBER OF CHARACTERS IN TEXT - NCHAR. NEXT, CALL GETNUM WHICH WILL PARSE THE USER TEXT STRING FOR NUMBERS. XNUM WILL BE AN ARRAY OF NUMBERS, AND K2 IS THE NUMBER OF NUMBERS FOUND.\n\nWRITE(FORM,100) 'ENTER LOOK-FROM VECTOR (X,Y,Z)\nCALL GETXT(TEXT,NCHAR,FORM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nLOOKAT(1) = 0.\nLOOKAT(2) = 0.\nLOOKAT(3) = 0.\nIF(K2 .EQ. 0) THEN\n WRITE(FORM,100) 'NO LOOK-FROM VECTOR SPECIFIED!'\n CALL PROMPT(FORM)\nELSE\n LOOKFR(1) = XNUM(1)\n LOOKFR(2) = XNUM(2)\n LOOKFR(3) = XNUM(3)\n CALL ATFROM(LOOKAT,LOOKFR)\nENDIF\n\nPROMPT FOR AND PERFORM A ROTATION FOR PART 1\n\nChapter One EXAMPLE PROBLEMS 1.12\nWRITE(FORM,100) 'X,Y,Z ROTATION ANGLES (DEGREES) FOR PART 1?'\n\nCALL GETXT(TEXT,NCHAR,FROM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nLOOKAT(1) = (1) - XNUM(1)\nLOOKAT(2) = (2) - XNUM(2)\nLOOKAT(3) = (3) - XNUM(3)\nCALL MODIFY('1',4,VALUE)\n\nPROMPT FOR AND PERFORM A TRANSLATE FOR PART 1\n\nWRITE(FORM,100) 'X,Y,Z TRANSLATION FOR PART 1?'\nCALL GETXT(TEXT,NCHAR,FROM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nVALUE(1) = XNUM(1)\nVALUE(2) = XNUM(2)\nVALUE(3) = XNUM(3)\nCALL MODIFY('1',5,VALUE)\n\nCREATE A NEW GROUP (SEE \"AN INTRODUCTION TO HIERARCHICAL DATA STRUCTURES\" IN APPENDIX B.)\n\nCALL DEFINE('TOP GROUP')\n\nCOPY THE GROUP \"ROOT\" INTO THE NEW GROUP AND CALL THE COPY \"COPY ROOT 1\"\n\nCALL ADDCAL('ROOT','COPY ROOT 1')\n\nCOPY ANOTHER COPY OF ROOT INTO THE NEW GROUP AND CALL THE COPY \"COPY ROOT 2\"\n\nCALL ADDCAL('ROOT','COPY ROOT 2')\n\nPROMPT THE USER FOR A TRANSLATE OF \"COPY ROOT 2\"\n\nWRITE(FORM,100) 'X,Y,Z TRANSLATION FOR COPY ROOT 2?'\nCALL GETXT(TEXT,NCHAR,FROM)\nCALL GETNUM(TEXT,NCHAR,XNUM,K2)\nVALUE(1) = XNUM(1)\nVALUE(2) = XNUM(2)\nVALUE(3) = XNUM(3)\nCALL MODIFY('COPY ROOT 2',5,VALUE)\n\nSET THE COLOR OF \"COPY ROOT 1\" TO GREEN, AND SET THE COLOR OF PART 1(PART 1 IS REALLY COPY 1) TO RED. ALSO SET THE SHADING ATTRIBUTE OF COPY 1 TO SMOOTH\n\nVALUE(1) = 0.\nVALUE(2) = 1.\nVALUE(3) = 0.\nCALL MODIFY('COPY ROOT 1', 8, VALUE)\nVALUE(1) = 1.\nVALUE(2) = 0.\nCALL MODIFY('1', 8, VALUE)\nVALUE(1) = 2.\nCALL MODIFY ('1', 11, VALUE)\n\nSET THE VIEWPORT TO THE UPPER LEFT QUARTER OF THE SCREEN\nCALL SETPRT(0.,5.,75)\nDISPLAY LINE DRAWING OF PICTURE\nCALL DISALL\n\nSET THE VIEWPORT TO THE UPPER RIGHT QUARTER OF THE SCREEN\nCALL SETPRT(.5,1.,75)\nSET THE HIDDEN LINE FLAG ON AND DISPLAY THE PICTURE IN FOUR STANDARD VIEWS\nCALL SETFLG('HIDDEN', .TRUE.)\nCALL FOURVW\n\nSET THE VIEWPORT TO THE LOWER LEFT QUARTER OF THE SCREEN\nCALL SETPRT(0.,5.,25)\nSET THE SHADED IMAGE FLAG AND DISPLAY THE PICTURE\nCALL SETFLG('SHADED', .TRUE.)\nCALL DISALL\n\nSET THE VIEWPORT TO THE LOWER RIGHT QUARTER OF THE SCREEN\nCALL SETPRT(.5,1.,25)\nSET THE DITHERING FLAG ON, AND DISPLAY THE RASTER IMAGE OVER\nCALL SETFLG('DITHER', .TRUE.)\nCALL DISALL\n\nFORMAT(A)\nSTOP\nEND\nChapter Two\n\nTECHNICAL REFERENCES\n\nThis chapter contains detailed descriptions of all the user-callable subroutines within RGDL. Use the information to write application programs for your needs.\n\nThe routines are listed in alphabetical order, each on a separate page. The function is listed at the top of each page, together with the name of the routine. The function of each routine is given, as well as parameters, common blocks, include blocks, and other routines that are used in conjunction with the given routine.\n\nIt is unlikely you will use the routines in alphabetical order, so we have provided an index of the routines according to their function on page vi, after the table of contents. An alphabetized index is also given on page iii. The index divided into functions will probably be the easiest way to find an unknown routine with a known function.\nSubroutine ACTGRP (grunam)\n\nSets the active group to an existing group.\n\nPARAMETERS\n\nin: grunam The name of an existing group to be set active.\n\nclass: grunam*(*)\nDECLARATION: Subroutine ADDCAL (giname, cpynam)\n\nFUNCTION: Adds a call (item or group) to the active group.\n\nPARAMETERS\n\nin: giname Name of group or item to be added to the active group.\n cpynam Copy name that gname will be referred to.\n\ncharacter: giname*(*) , cpynam*(*)\n\nCOMMON BLOCKS: /CHFWAS/\n/CLIMIT/\n/CMEMRY/\n\nChapter Two TECHNICAL REFERENCES 2.3\nDECLARATION: Entry ANFILI (inqnam)\n\nFUNCTION: Returns the animation extension.\n\nAn animation file extension of '@#$' indicates that animation is not open.\n\nPARAMETERS\n\nout: inqnam Name of the animation extension.\n\ncaracter: inqnam(3)\n\nSEE ALSO: ANFILS\nDECLARATION: Entry ANFILS (newnam)\n\nFUNCTION: Stores the animation extension.\n\nAn animation file extension of '@#$' indicates that animation is not open. Use ANIDRV to open animation.\n\nPARAMETERS\n\nin: newnam Name of the new animation extension.\n\ncharacter: newnam(3)\n\nSEE ALSO: ANFILI\nANIDRV\nDECLARATION: Subroutine ANIDRV\n\nFUNCTION: Drives the animation module. ANIDRV does many basic functions like opening and closing the animation module, setting up subframes, and setting up spline control.\n\nAll animation interfacing should be performed through ANIDRV.\n\nCOMMON BLOCKS: /CHFWAS/\n/DEVI/\n/CMEMRY/\nDECLARATION: Entry AROCLR\n\nFUNCTION: Clears the displacement arrow arrays.\n\nCall AROCLR once for each part containing displacement vector arrows.\nDECLARATION: Subroutine ATFROM (lookat, lookfr)\n\nFUNCTION: Creates the viewing matrix based on the look-from and look-at positions.\n\nCoordinates are in world coordinates.\n\nPARAMETERS\n\nin: lookat Look-at position.\nlookfr Look-from position.\n\nreal: lookat(3), lookfr(3)\n\nCOMMON BLOCKS: /VEWSTF/\n\nSEE ALSO: INQLAF\nDECLARATION: Subroutine AUTOON\n\nFUNCTION: Turns auto center off.\n\nCOMMON BLOCKS: /DEVI/\n /VEWSTF/\nDECLARATION: Subroutine BEGANI (aninam)\n\nFUNCTION: Starts the animation, opens necessary files, and initializes all appropriate variables.\n\nPARAMETERS\n\nin: aninam The three character extension names used for animation files.\n\ncharacter: aninam(3)\n\nCOMMON BLOCKS: /CHFWAS/ /CLIMIT/ /CMEMRY/ /DEVI/\nDECLARATION: Subroutine CAMERA\n\nFUNCTION: Acts as the interface to a camera for animation.\n\nCAMERA gets called after each frame is displayed. You can modify this routine for anything you wish to do after a frame is shown. For example, you may want to interface to a computer-controlled camera.\nDECLARATION: Subroutine CENTER\n\nFUNCTION: Sets up the viewing matrix, if not already specified. Also sets up the window and clipping planes to center the model.\n\nThe limits of the scene to be displayed must first be set up in SETLIM. Normally, this is done by a call to TRAVRS.\n\nCOMMON BLOCKS: /DEVI/\n/VEWSTF/\n/RESOLT/\n\nSEE ALSO: SETLIM\nGETLIM\nTRAVRS\n**DECLARATION:** Subroutine CHRNUM (number, lenchr, chrint, nchars)\n\n**FUNCTION:** Converts integer data into an equivalent character string.\n\n*Negative numbers are not allowed.*\n\n**PARAMETERS**\n\n- **in:**\n - lenchr: Maximum length of the string.\n - number: The integer number to be made into a character string.\n\n- **out:**\n - chrint: The character string representation of an integer.\n - nchars: Maximum number of characters in the string to be returned.\n\n**integer:** nchars, lenchr, number\n\n**character:** chrint(*)\nDECLARATION: Subroutine CLPLIN (corbeg, corend, wxmin, wxmax, wymin, wymax, plot)\n\nFUNCTION: Clips lines in x and y.\n\nAll coordinates are eye coordinates.\n\nPARAMETERS\n\nin: corbeg X,Y,Z coordinate triplet of beginning point; may be modified after clipping.\ncorend X,Y,Z ending triplet of line may be modified after clipping.\nwxmin Minimum X window coordinate.\nwxmax Maximum X window coordinate.\nwymin Minimum Y window coordinate.\nwymax Maximum Y window coordinate.\n\nout: plot .TRUE. if line is visible or partly visible.\nreal: corbeg(3), corend(3), wxmin, wxmax, wymin, wymax\n\nSEE ALSO: CLPPOL\n\nChapter Two TECHNICAL REFERENCES 2.14\nDECLARATION: Subroutine CLPPOL (nedges, cordin, polnin, funcin, clpfun, clpnor, wxmin, wxmax, wymin, wymax, plot)\n\nFUNCTION: CLPOLL clips polygons against the x and y boundaries.\n\nThe coordinate, normal, and function arrays must close the polygon. For example, the first vertex location is the same as the nedges + 1 location.\n\nAll coordinates are eye coordinates.\n\nPARAMETERS\n\nin: clpfun .TRUE. if clipping function values are being clipped.\nclpnor .TRUE. if clipping normals are being clipped.\nwxmin Minimum x window coordinate.\nwxmax Maximum x window coordinate.\nwymin Minimum y window coordinate.\nwymax Maximum y window coordinate.\nnedges Number of edges in the polygon.\ncordin Coordinates of polygon.\ncordin(1,1) = X coordinate of first polygon vertex\ncordin(2,1) = Y coordinate of first polygon vertex\nCordin may be modified after clipping.\npolnin Normals of polygon after clipping.\npolnin(1,1) = X component of unit normal at vertex l\npolnin(2,1) = Y component of unit normal at vertex l\nPolnin may be modified after clipping.\nfuncin Function values of polygon after clipping.\nFuncin may be modified after clipping.\n\nout: plot Logical; .TRUE. if polygon is visible after clipping.\n\nreal: wxmin, wxmax, wymin, wymax, cordin(3,*), polnin(3,*), funcin(*)\n\ninteger: nedges\n\nlogical: clpfun, clpnor, plot\n\nSEE ALSO: CLPPZE CLPLIN\n**DECLARATION:** Subroutine CLPPZE (nedges, cordin, polnin, funcin, clpfun, clpnor, zmin, zmax, plot)\n\n**FUNCTION:** Clips polygons against the z boundaries.\n\n**PARAMETERS**\n\n- **in:**\n - clpfun .TRUE. if clipping function values are being clipped.\n - clpnor .TRUE. if clipping normals are being clipped.\n - zmin Distance from eye to nearest clipping plane.\n - zmax Distance from eye to farthest clipping plane.\n - nedges Number of edges in the polygon. Nedges may be modified after clipping.\n - cordin Coordinates of polygon. Cordin may be modified after clipping.\n - polnin Normals of polygon. Polnin may be modified after clipping.\n - funcin Function values of polygon. Funcin will be modified after clipping.\n\n- **out:**\n - plot .TRUE. if polygon is visible.\n\n- **real:**\n - zmin, zmax, cordin (3,*), polnin (3,*), funcin (*)\n\n- **integer:**\n - nedges\n\n- **logical:**\n - plot, clpfun, clpnor\n\n**SEE ALSO:** CLPPOL\n\nCLPLIN\nDECLARATION: Subroutine CNTBAR\n\nFUNCTION: Outputs contour legend bar for contours.\n\nContours should be set up CNTBAR before calling this routine by calling SETFRN.\n\nSEE ALSO: SETFLG\nINQFRN\nSETFRN\nINQFLG\nSETCNT\nDECLARATION: Subroutine CNTRPT (nedges, coords, xcentr)\n\nFUNCTION: Calculates a polygon's center point.\n\nThe coordinate array should close the polygon.\n\nPARAMETERS\n\nin: nedges Number of vertices in a polygon.\n coords Coordinate array for polygon.\n\nout: xcentr Coordinate array of center point.\n\nreal: coords(3,*), xcentr(3)\n\ninteger: nedges\nDECLARATION: Function COLERR (color)\n\nFUNCTION: Calculates the error between the desired color and the next lowest color in the look-up table.\n\nPARAMETERS\n\nin: color The intensity of either the r, g, or b component of the desired color. (The range of color is from 0.0 to 1.0).\n\nreal: color\nCOLORS\n\nDECLARATION: Subroutine COLORS (nedges, atribt, polfun, coords, polnor, colnod, trnnod)\n\nFUNCTION: Computes color values at polygon nodes according to user-defined light sources.\n\nAll coordinates are in the eye coordinate system.\n\nPARAMETERS\n\nin: nedges Number of vertices in the polygon.\n atribt Attribute list for polygon.\n coords Coordinate array for polygon vertices.\n polfun Polygon function values at the vertices.\n polnor Normals of the polygon vertices.\n\nout: colnod Red, green, and blue color intensity at polygon vertices.\n trnnod Transparency values of polygon vertices.\n\nreal: atribt(*), colnod(3,*), coords(3,*), polfun(*), trnnod(*), polnor(3,*)\n\ninteger: nedges\n\nCOMMON BLOCKS: /CFLAGS/\n /CATTRI/\n /CHFWAS/\n /CMEMRY/\n\nChapter Two TECHNICAL REFERENCES 2.20\n**DECLARATION:** Subroutine COPNUM (sordex, numcop, jroot, jchild, itorgr, cpynam)\n\n**FUNCTION:** Given the copy number, gets the copy name together with its copy item and parent.\n\n**PARAMETERS**\n\n- **out:**\n - sordex: Sort number associated with the instance.\n - cpynam: Copy name associated with sordex.\n - jroot: Root group number.\n - jchild: Item or group number of the copy name.\n - itorgr: Flag 1 if a group; 0 if an item.\n - numcop: Copy number.\n\n- **integer:** sordex, jroot, jchild, itorgr, numcop\n\n- **character:** cpynam*(*)\n\n**SEE ALSO:** GETCOP\nDECLARATION: Subroutine DEFALT (atlist)\n\nFUNCTION: Sets up a default attributes list.\n\nPARAMETERS\n\nout: atlist Current attribute list.\nreal: atlist (maxiaa)\n\nCOMMON BLOCKS: /CATTRI/\n/CLIMIT/\nDEFINE\n\nDECLARATION: Subroutine DEFINE (grunam)\n\nFUNCTION: Defines and activate a new group.\n\nPARAMETERS\n\n in: grunam The name of the new group to be activated.\n character: grunam(*)\nDECLARATION: Subroutine DELETE (cpynam)\n\nFUNCTION: Deletes a call to an instance.\n\nPARAMETERS\n\n in: cpynam Copy name to be deleted from the database.\n character: cpynam*(*)\nDECLARATION: Subroutine DISALL\n\nFUNCTION: Displays the picture for all options.\n\nPARAMETERS\n\nCOMMON BLOCKS: /DEVI/\n /CMEMRY/\n /CHFWAS/\n /CLIMIT/\nDECLARATION: Subroutine DISTXT (string, nchars, r, g, b, ix, iy)\n\nFUNCTION: Displays text strings.\n\nPARAMETERS\n\nin: \n string Text string to be displayed.\n nchars Number of characters in string.\n r, g, b Desired color of text (0.0-1.0).\n ix, iy Origin of the string in screen coordinates.\n\nreal: \n r, g, b\n\ninteger: \n nchars, ix, iy\n\ncharacter: \n string(*)\nDECLARATION: Subroutine DODITH (r,g,b)\n\nFUNCTION: DODITH performs dithering for a pixel.\n\nPARAMETERS\n\nin: r, g, b Color components of the pixel (0.0 - 1.0) modified on return.\n\nreal: r, g, b\nDECLARATION: Subroutine DRWABS (ix,iy)\n\nFUNCTION: Draws a line from the current location to the specified point (ix,iy).\n\nPARAMETERS\n\nin: ix,iy The screen coordinates of the point to be drawn to. The (0,0) point is in the lower left corner, x increases from left to right, and y increases from bottom to top. The ix,iy point should become the current point after the draw command.\n\ninteger: ix,iy\nDECLARATION: Subroutine DRWBOR\n\nFUNCTION: Draws a border around the current viewport.\n\nWhen using DRWBOR, you must put graphics device into and out of the graphics mode.\n\nSEE ALSO: SETMOD\nDECLARATION: Subroutine ERASE\n\nFUNCTION: Clears the current viewport to the background color.\nDECLARATION: Subroutine EXTCOP (cpynam, ctm, atlist)\n\nFUNCTION: Extracts transformation and attribute information for an instance.\n\nPARAMETERS\n\nin: cpynam The instance name.\n\nout: atlist Attribute list for the instance.\n ctm Transformation matrix for the instance.\n\nreal: atlist(maxatt), ctm(4,4)\n\ncharacter: cpynam(*)\n\nCOMMON BLOCKS: /CHFWAS/\n /CLIMIT/\n /CMEMRY/\n\nSEE ALSO: RPLCOP\nDECLARATION: Subroutine FNDFRM (chrfrm, keyfrm, subfrm, ierr)\n\nFUNCTION: Finds the keyframe and subframe from a character string of the form keyframe.subframe.\n\nPARAMETERS\n\nin: chrfrm A character string defined in the form keyfrm.subfrm.\n\nout: keyfrm Keyframe number.\nsubfrm Subframe number.\nierr Error flag. 0 if operation was successful; 1 if chrfrm was not in the form keyframe.subframe.\n\ninteger: subfrm, ierr, keyframe\n\ncharacter: chrfrm(*)\nDECLARATION: Subroutine FOURVW\n\nFUNCTION: FOURVW displays the four standard views.\n\nCOMMON BLOCKS: /CFLAGS/ \n/RESOLT/\nDECLARATION: Subroutine FRINGE (nlevel, colfnc, fnclev, valnod, xir, xig, xib)\n\nFUNCTION: Calculates color at a node of a polygon when fringes are on.\n\nFringes should be set up using SETFRN before calling FRINGE.\n\nPARAMETERS\n\nin: colfnc Color at each fringe function level.\n fnclev Function value at each level.\n nlevel Number of function levels.\n valnod Function value at the node.\n\nout: xir Red color component at node.\n xig Green color component at node.\n xib Blue color component at node.\n\nreal: colfnc(3, nlevel), fnclev(nlevel), xir, xig, xib, valnod\n\ninteger: nlevel\n\nSEE ALSO: SETFLG\n FRNBAR\n INQFRN\n SETFRN\n INQFLG\nDECLARATION: Subroutine FRNBAR\n\nFUNCTION: Displays fringe bar (legend) for color fringes.\n\nFringes should be set using SETFRN before calling FRNBAR.\n\nSEE ALSO: FRINGE\nSETFLG\nINQFRN\nSETFRN\nINQFLG\nDECLARATION: Entry GENTXT\n\nFUNCTION: Generates text string for display.\n\nSEE ALSO: TXTDIS\n TXTINT\nDECLARATION: Entry GETAGR (i)\n\nFUNCTION: Returns the active group number.\n\nPARAMETERS\n\nout: i Active group number.\n\ninteger: i\n\nSEE ALSO: NEWGRP\nDECLARATION: Entry GETCLP (znear, zfar, zdist)\n\nFUNCTION: Gets z clipping information.\n\nPARAMETERS\n\nout: znear Distance from eye to the nearest z clipping plane.\nzfar Distance from eye to the farthest z clipping plane.\nzdist Distance from znear to zfar.\n\nreal: znear, zfar, zdist\n\nSEE ALSO: SETCLP\nDECLARATION: Subroutine GETCOM (text, nchar, word, n, key, kl)\n\nFUNCTION: Parses a text string for key words.\n\nPARAMETERS\n\nin: \nn Number of words in the key word array.\nword Array of key words that are being looked for.\n nchar Number of characters in entered text string.\ntext Entered text string to be parsed.\n\nout: kl Number of key words found in the text string.\nkey Array of key word starting locations in the word array that were found in the text string.\n\ninteger: n, kl, nchar, key(*)\ncharacter: text*73, word(n)*4\n\nSEE ALSO: GETNUM\nDECLARATION: Subroutine GETCOP (cpynam, iflag, jroot, jchild, itorgr, sordex, numcop, postfl)\n\nFUNCTION: Given the copy name, gets the copy number and associated indexes.\n\nPARAMETERS\n\nin: cpynam Copy name to get information on.\n iflag 1 if adding a copy name.\n 2 if deleting a copy name.\n 3 if traversing with the copy name to get group and item information.\n 4 if purging all calls to an item or group.\n 5 if printing the copy names to the screen.\n sordex Sort number for groups and items.\n itorgr Flag 1 if a group; 0 if an item.\n numcop Copy number associated with the copy name.\n jroot Root group number.\n jchild Item or group number of the copy name.\n\nout: postfl 0 if the copy is posted; 1 if unposted.\n sordex Sort number for groups and items.\n itorgr Flag 1 if a group; 0 if an item.\n numcop Copy number associated with the copy name.\n jroot Root group number.\n jchild Item or group number of the copy name.\n\nreal: postfl\n\ninteger: iflag, sordex, itorgr, numcop\n\ncharacter: cpynam(*)\n\nSEE ALSO: COPNUM\nDECLARATION: Entry GETDEF (numcol, red, grn, blu)\n\nFUNCTION: Returns the red, green, and blue color intensities for color number numcol.\n\nAll color values are from 0 to 1.\n\nPARAMETERS\n\nout: numcol Number of the default color to return information for.\nred Red intensity default color number numcol.\ngreen Green intensity default color number numcol.\nblu Blue intensity default color number numcol.\n\nreal: red, grn, blu\n\ninteger: numcol\n\nSEE ALSO: SETDEF\nDECLARATION: Subroutine GETGRU (grpnam, jroot, iflag)\n\nFUNCTION: Gets group name and group number relationships.\n\nPARAMETERS\n\nin: grpnam Name of the group. Grpnam will be in or out depending on iflag option).\n iflag 1 if adding a group name to the list.\n 2 if deleting a group from the list.\n 3 if getting the name from the number.\n 4 if getting the number from the name.\n 5 if listing out defined group names.\n 6 if changing the name of a group.\n\nout: jroot Number of the group. Jroot will be in or out depending on iflag option).\n\ninteger: jroot, iflag\n\ncharacter: grpnam(*)\n\nSEE ALSO: GETITM\nDECLARATION: Subroutine GETITM (itname, jchild, iflag)\n\nFUNCTION: Gets item name and item number relationships.\n\nPARAMETERS\n\nin: itname Name of the item. Itname will be in or out depending on iflag option.\n iflag 1 if adding a item name to the list. \n 2 if deleting a item from the list. \n 3 if getting the name from the number. \n 4 if getting the number from the name. \n 5 if listing out defined item names.\n\nout: jchild Number of the item (in or out depending on iflag option).\n\ninteger: jchild, iflag\ncharacter: itname(*)\n\nSEE ALSO: GETGRU\n\nGETITM\nDECLARATION: Entry GETLIM (small, big)\n\nFUNCTION: Returns the maximum and minimum model coordinates of all parts processed with MAXMIN.\n\nPARAMETERS\n\nout: big Maximum coordinates returned.\nsmall Minimum coordinates returned.\n\nreal: small(3), big(3)\n\nCOMMON BLOCKS: /CLIMIT/\n/MASTER/\n\nSEE ALSO: MAXMIN\nDECLARATION: Subroutine GETNUM (text, nchar, xnum, k2)\n\nFUNCTION: Parses a text string for numbers.\n\nPARAMETERS\n\nin: nchar Number of characters in line of entered text.\n text Entered text string to be parsed.\n\nout: k2 Number of numbers found in the text string.\n xnum Array of numbers found in the text string.\n\nreal: xnum(40)\n\ninteger: k2, nchar\n\ncharacter: text*73\n\nSEE ALSO: GETCOM\nGETWND\n\nDECLARATION: Entry GETWND (xmin, xmax, ymin, ymax)\n\nFUNCTION: Inquires on the world window bounds. The scene is clipped to these values.\n\nPARAMETERS\n\nout: xmin Minimum x world coordinate for window currently set.\nxmax Maximum x world coordinate for window currently set.\nymin Minimum y world coordinate for window currently set.\nymax Maximum y world coordinate for window currently set.\n\nreal: xmin, xmax, ymin, ymax\n\nSEE ALSO: SETWND\n**DECLARATION:** Subroutine GETXT (text, nchar, textin)\n\n**FUNCTION:** Prompts for and retrieves a text string.\n\n**PARAMETERS**\n\n- **in:** textin Optional prompt string that will be written to display device prior to reading text string. If textin is blank, the prompt will not be displayed.\n- **out:** nchar Number of characters in line of entered text.\n text Entered text string.\n- **integer:** nchar\n- **character:** text*73, textin*80\nDECLARATION: Subroutine GLBACT (code, vall, val2, val3, val4, val5, val6)\n\nFUNCTION: Provides an interface between global actions and the animate module.\n\nIt is not necessary to call GLBACT unless animation is being done.\n\nPARAMETERS\n\nin: code Code that determines the operation performed in GLBACT.\n\n'SCL' Global scales for this subroutine.\n'ROT' Global rotate.\n'COL' Background color.\n'WND' Window.\n'PER' Perspective angle.\n'DST' Distance.\n'FRM' Look-from position or vector.\n'ATT' Look-for position.\n'CLP' Z-clipping planes.\n'VEW' Viewport.\n'LIT' Lightsource information.\n'FOG' Fog planes.\n\nvall Vall through val6 are values needed to perform wanted operation.\n\nreal: vall, val2, ... val6\n\ncharacter: code*3\n\nCOMMON BLOCKS: /CMEMRY/\n/CHFWAS/\nSubroutine GLBAXS (tm, atribt)\n\nDraws the global axis.\n\nin: \n tm Viewing matrix.\n atribt Attribute list.\n\nreal: \n tm(4,4), atribt (maxiaa)\n\nCOMMON BLOCKS: \n /CATTRI/ \n /CFLAGS/ \n /CLIMIT/ \n /RESOLT/ \n /VEWSTF/\nDECLARATION: Subroutine GRAINT\n\nFUNCTION: Initializes the graphics package.\n\nGRAINT must always be called before any other graphics application is called.\n\nCOMMON BLOCKS: /CATTRI/ /CHFWAS/ /CLIMIT/ /CMEMRY/ /DEVI/ /VEWSTF/\nDECLARATION: Subroutine GTUROX (theta, ctm)\n\nFUNCTION: Concatenates a right-handed rotation about the x-axis to a transformation matrix.\n\nPARAMETERS\n\nin: theta Angle in degrees.\n ctm Current transformation matrix that is modified on return.\n\nreal: theta, ctm(4,4)\n\nSEE ALSO: GTUROY\n GTUROZ\n GTUSCL\n GTUTRN\n INT4X4\nGTUROY\n\nDECLARATION: Subroutine GTUROY (theta, ctm)\n\nFUNCTION: Concatenates a right-handed rotation about y-axis to a\ntransformation matrix.\n\nPARAMETERS\n\nin: theta Angle in degrees.\n ctm Current transformation matrix modified on return.\n\nreal: theta, ctm(4,4)\n\nSEE ALSO: GTUROX\n GTUROZ\n GTUSCL\n GTUTRN\n INT4X4\nDECLARATION: Subroutine GTUROZ (theta, ctm)\n\nFUNCTION: Concatenates a right-handed rotation about z-axis to a transformation matrix.\n\nPARAMETERS\n\nin: theta Angle in degrees.\n ctm Current transformation matrix modified on return.\nreal: theta, ctm(4,4)\n\nSEE ALSO: GTUROX\n GTUROY\n GTUSCL\n GTUTRN\n INT4X4\nDECLARATION: Subroutine GTUSCL (sx, sy, sz, ctm)\n\nFUNCTION: Concatenates scalings to a transformation matrix.\n\nPARAMETERS\n\nin: sx Scaling in x-direction.\n sy Scaling in y-direction.\n sz Scaling in z-direction.\n ctm Current transformation matrix modified on return.\n\nreal: sx, sy, sz, ctm(4,4)\n\nSEE ALSO: GTUROX\n GTUROY\n GTUROZ\n GTUTRN\n INT4X4\nDECLARATION: Subroutine GTUTRN (dx, dy, dz, ctm)\n\nFUNCTION: Concatenates a translation to a transformation matrix.\n\nPARAMETERS\n\nin: dx Translation in x-direction.\ndy Translation in y-direction.\ndz Translation in z-direction.\nctm Current transformation matrix modified on return.\n\nreal: dx, dy, dz, ctm(4,4)\n\nSEE ALSO: GTUROX\n GTUROY\n GTUROZ\n GTUSCL\n INT4X4\n\nChapter Two TECHNICAL REFERENCES 2.55\nDECLARATION: Subroutine HIDLIN (prtcol)\n\nFUNCTION: Perform hidden line removal and contour generation.\n\nHIDLIN can be called after all polygons have been loaded with STOREL.\n\nPARAMETERS\n\nin: prtcol Array of rgb colors for each part in the picture.\n\nreal: prtcol(3,*)\n\nCOMMON BLOCKS: /HIDSTF/\n /KEEP/\n\nSEE ALSO: STOREL\nDECLARATION: Subroutine HIDSUR\n\nFUNCTION: Performs hidden surface removal.\n\nHIDSUR can be called after calls to INTHID and INTHD2, and after all polygons have been packed down.\n\nCOMMON BLOCKS: /RESOLT/\n/CNMERY/\n/CHFWAS/\n\nSEE ALSO: INTHID\nINTHD2\nDECLARATION: Subroutine HUDITM (jpar, jitm, jcopy)\n\nFUNCTION: Deletes an item call from the hierarchical data structure.\n\nPARAMETERS:\n\nin: jpar Parent group number.\n jcopy Instance copy number.\n jitm Item number.\n\ninteger: jpar, jcopy, jitm\nINCONG\n\n**DECLARATION:** Entry INCONG (congin)\n\n**FUNCTION:** Returns the continuity for the look-at and look-from locations for animation.\n\n**PARAMETERS**\n\n- **out:** congin Array of continuity values.\n- **real:** congin(maxprt,2)\n**DECLARATION:** Subroutine INITGI (grpdex, grsort, trndex, gstart, sgrcnt, sitcnt, namgrp, namitm, igrupa, ichida, iorga, numcpy, namcpy)\n\n**FUNCTION:** Initializes groups and items.\n\n**PARAMETERS**\n\n**in:**\n- grpdex Group number array.\n- grsort Group sort array.\n- igrupa Root group array.\n- trndex Transformation number index array.\n- gstart Group start array.\n- sgrcnt Subgroup counter array.\n- sitcnt Subitem counter array.\n- namgrp Group names array.\n- namitm Item names array.\n- ichida Child array.\n- iorga Item or group flag array.\n- numcpy Copy number array.\n- namcpy Copy name array.\n\n**integer:**\n- namgrp(maxchr,0:maxgrp)\n- namitm(maxchr,0:maxitm)\n- namcpy(maxchr,0:maxins)\n- igrupa(maxins)\n- ichida(maxins)\n- iorga(maxins)\n- numcpy(maxins)\n- grpdex(maxins)\n- grsort(maxins)\n- trndex(maxins)\n- gstart(maxgrp)\n- sgrcnt(maxgrp)\n- sitcnt(maxgrp)\nDECLARATION: Entry INQBCC (red, green, blue)\n\nFUNCTION: Returns on the background color.\n\nAll values are from 0 to 1.\n\nPARAMETERS\n\nout: red Red intensity of background color.\ngreen Green intensity of background color.\nblue Blue intensity of background color.\n\nreal: red, green, blue\n\nSEE ALSO: SETBGC\nDECLARATION: Entry INQBOX (npart, cormax, cormin)\n\nFUNCTION: Returns the x,y,z limits of a bounding box for an instance.\n\nPARAMETERS\n\nin: npart Number of parts in the model.\ncormax Maximum x, y, and z coordinates of box.\ncormin Minimum x, y, and z coordinates of box.\n\nreal: cormax(3), cormin(3)\n\ninteger: npart\n\nSEE ALSO: SETBOX\nDECLARATION: Entry INQCNT (iflag)\n\nFUNCTION: Returns the number of defined contour levels.\n\nPARAMETERS\n\nout: iflag Number of contour levels to be displayed.\ninteger: iflag\n\nSEE ALSO: SETCNT\n**DECLARATION:** Entry INQCON (coninq)\n\n**FUNCTION:** Returns the instance continuities at the keyframes for animation.\n\n**PARAMETERS**\n\n- `out: coninq` Array of continuities.\n- `real: coninq(maxfrm, maxprt)`\nDECLARATION: Subroutine INQDEV (shaded, polfil, hrdwar)\n\nFUNCTION: Checks to see if the device has special hardware capabilities that are being taken advantage of in display. INQDEV also checks to see if the device can fill polygons or do shading.\n\nPARAMETERS\n\nout: hrdwar .TRUE. if special hardware available.\npolfil .TRUE. if polygon fills available.\nshaded .TRUE. if shaded images possible.\n\nlogical: hrdwar, polfil, shaded\nDECLARATION: Entry INQDSP (xdis, ydis, zdis, valnod)\n\nFUNCTION: Returns the magnitude of a displacement at a node.\n\nPARAMETERS\n\nin: xdis X displacement of a node.\nydis Y displacement of a node.\nzdis Z displacement of a node.\n\nout: valnod Magnitude of displacement of the node.\n\nreal: xdis, ydis, zdis, valnod\nINQDST\n\nDECLARATION: Entry INQDST (dist)\n\nFUNCTION: Inquires distance from eye to look-at point.\n\nUse INQDST only in perspective angle mode and when not doing auto center.\n\nPARAMETERS\n\nin: dist Distance from eye to look-at point.\n\nreal: dist\n\nCOMMON BLOCKS: /VEWSTF/\n\nSEE ALSO: SETDST\nDECLARATION: Entry INQFLG (cflag, lflag)\n\nFUNCTION: Inquires on global flags set.\n\nPARAMETERS\n\nin: cflag Key that indicates what is being inquired on one of the following:\n\n'ALIA' Anti-aliasing flag.\n'SHDO' Shadow flag.\n'AXIS' Axis are to be drawn flag.\n'BOUN' Draw bounding box instead of model flag.\n'BORD' Draw border flag.\n'CENT' Auto center flag.\n'COLO' Draw colored lines flag.\n'DISP' Displacements are performed flag.\n'DITH' Dithering status flag.\n'ELEM' Element labeling flag.\n'FOUR' Four view flag.\n'GLAS' Transparency flag.\n'HAEZ' Haze/fog flag.\n'HIDD' Hidden line flag.\n'LAGE' Label contours flag.\n'LEGE' Display contour legend flag.\n'NODE' Node labeling flag.\n'ONED' Warped polygons on edge flag.\n'OVER' Overlay flag.\n'PERA' Perspective or windowing toggle flag.\n'PERS' Perspective flag.\n'POLY' Polygon clipping flag.\n'POOR' Poorman flag.\n'SHAD' Shaded images flag.\n'SYMM' Symmetric contours or fringes flag.\n'VECT' Vector arrows flag.\n'WARN' Function warping flag.\n'TEXT' Text display flag.\n'TK41' Tektronix 4129 hardware flag.\n'LABV' Label for views flag.\n'PLYF' Polygon fill shaded images flag.\n\nout: lflag .TRUE. or .FALSE. status of cflag.\n\ninteger: iflag\ncharacter: cflag(*)\n\nCOMMON BLOCKS: /CFLAGS/\n\nSEE ALSO: SETFLG\nDEVELOPMENT: Entry INQFNC (nlevel, valmin, valmax)\n\nFUNCTION: Returns the number of color fringes set, and the minimum and maximum range of fringes.\n\nSETFNC should be called before calling INQFNC.\n\nPARAMETERS\n\nout: nlevel Number of function levels defined.\nvalmin Minimum value of color fringes.\nvalmax Maximum value of color fringes.\n\nreal: valmin, valmax\n\ninteger: nlevel\n\nSEE ALSO: SETFNC\nDEVELOPMENT: Entry INQFOG (dstner, dstfar)\n\nFUNCTION: Returns the distance to the nearest and farthest fog planes.\n\nPARAMETERS\n\nout: dstnera Distance to nearest fog plane.\n dstfar Distance to farthest fog plane.\n\nreal: dstner, dstfar\n\nSEE ALSO: SETFOG\nDECLARATION: Entry INQFRM (numfrm)\n\nFUNCTION: Returns on the animation keyframe being worked on.\n\nYou should call ANFILI before calling INQFRM to see if animation is really going on.\n\nPARAMETERS\n\nout: numfrm The number of the keyframe being worked on.\n\ninteger: numfrm\n\nSEE ALSO: SETFRM ANFILI\nDECLARATION: Entry INQFRN (iflag)\n\nFUNCTION: Returns the number of fringe levels.\n\nPARAMETERS\n\nout: iflag Number of fringe levels to be displayed.\n\ninteger: iflag\n\nSEE ALSO: SETFRN\nDECLARATION: Entry INQGLB (tm)\n\nFUNCTION: Returns the global transformation matrix.\n\nPARAMETERS\n\nout: tm Transformation matrix.\nreal: tm(4,4)\n\nSEE ALSO: SETGLB\nROTATE\nSCALE\nRESET\n**DECLARATION:** Subroutine INQLAF (lookat, lookfr, icentr)\n\n**FUNCTION:** Returns the look-at and look-from position. If icentr is .TRUE., INQLAF will return a vector for lookfr.\n\n**PARAMETERS**\n\n- **in:** icentr .TRUE. if auto-center is on.\n- **out:** lookat Look-at position.\n lookfr Look-from position.\n- **real:** lookat(3), lookfr(3)\n- **logical:** icentr\n\n**COMMON BLOCKS:** /VEWSTF/\nINQLEV\n\n**DECLARATION:** Entry INQLEV (nlevel, cofnc, fncev)\n\n**FUNCTION:** Inquires on the number of function levels, and the function value and color used with each level for fringes.\n\n**PARAMETERS**\n\n- **out:**\n - nlevel: Number of function levels defined.\n - cofnc: Array of colors at each function level.\n - fncev: Array of function values at each level.\n\n- **real:** cofnc (3,maxlev), fncev (3,maxlev)\n\n- **integer:** nlevel\nDECLARATION: Subroutine INQLIT (litnum, xltint, litloc, xltxyz)\n\nFUNCTION: Given the light source number, INQLIT returns intensity of the light, whether or not it is at the eye of the observer, and returns its position if not at the eye of the observer.\n\nPARAMETERS\n\nin: litnum Maximum number of lights allowed.\n\nout: xltint Light source intensity.\n litloc Light source location flag:\n 0 - at the eye of the observer\n 1 - at a specified location\n 2 - on a specified vector at infinity\n xltxyz x,y,z light source locations.\n\nreal: xltint, xltxyz (3)\n\ninteger: litnum, litloc\n\nCOMMON BLOCKS: /CHFWAS/\n /CMEMRY/\n\nSEE ALSO: LITSRC\nINQPER\n\nDECLARATION: Entry INQPER (anginq)\n\nFUNCTION: Inquires perspective angle.\n\nUse INQPER only if you are in the perspective mode.\n\nPARAMETERS\n\nout: anginq Perspective angle that is currently set (in degrees).\n\nreal: anginq\n\nSEE ALSO: SETPER INQFLG\nENTRY INQPRT (ileft, iright, ibottom, itop)\n\n**FUNCTION:** Returns the viewport boundaries.\n\n*All coordinates are screen coordinates.*\n\n**PARAMETERS**\n\n- `out`: ileft Left viewport boundary.\n- `out` : iright Right viewport boundary.\n- `out`: ibottom Bottom viewport boundary.\n- `out`: itop Top viewport boundary.\n\n**integer:** ileft, iright, itop, ibottom\n\n**SEE ALSO:** SETPRT\nEntry INQRAT (speed)\n\nReturns the instance rates at the keyframes for animation.\n\nout: speed Array of rates.\nreal: speed(maxfrm,maxprt)\nDECLARATION: Entry INQREF (ncolor, colfnc)\n\nFUNCTION: Inquires on the reference colors for color fringes.\n\nPARAMETERS\n\nout: ncolor Number of reference colors defined.\ncolfnc Array of colors at each function level.\nreal: colfnc (3, maxlev)\ninteger: ncolor\n\nSEE ALSO: INQLEV\n INQFNC\n SETREF\nDECLARATION: Entry INQSCL (scalex, scaley)\n\nFUNCTION: Inquires on the window to viewport scale factors.\n\nSETSCL must be called before calling this routine.\n\nPARAMETERS\n\nout: scalex X direction scale factor.\nscaley Y direction scale factor.\n\nreal: scalex, scaley\n\nCOMMON BLOCKS: /RESOLT/\n\nSEE ALSO: SETSCL\nDECLARATION: Entry INQSPL (splinq)\n\nFUNCTION: Returns the instance on spline flags at the keyframes for animation.\n\nPARAMETERS\n\nout: splinq Array of spline flags for global.\n\nreal: splinq(maxfrm,maxprt)\nDECLARATION: Entry INQSUB (isub)\n\nFUNCTION: Returns the number of subframes that exist between the frames for animation.\n\nPARAMETERS\n\nout: isub Array of subframes.\n\ninteger: isub(maxfrm)\n\nSEE ALSO: INQFRM\nANFILI\nDECLARATION: Entry INQTEN (teninq)\n\nFUNCTION: Returns the instance tensions at the keyframes for animation.\n\nPARAMETERS\n\nout: teninq Array of tension for global.\nreal: teninq(maxfrm, maxprt)\n**DECLARATION:** Entry INQTXT (mesage, xsize, ysize, twodim, xpos, ypos, zpos, xang, yang, zang, r, g, b, xslant, i, nsav)\n\n**FUNCTION:** Inquires on the text string attributes.\n\n**PARAMETERS**\n\n**in:**\n- i: Index of text string to retrieve.\n\n**out:**\n- nsav: Total number of stored messages.\n- mesage: The text string array.\n- xsize: X dimension factor.\n- ysize: Y dimension factor.\n- twodim: If .TRUE. message is 2-D.\n- if .FALSE., strings are in 3-D text.\n- xpos: X position of text string in world coordinate.\n- ypos: Y position of text string in world coordinate.\n- zpos: Z position of text string in world coordinate.\n- xang: X directional vector.\n- yang: Y directional vector.\n- zang: Z directional vector. Angle of text string if 2-d.\n- r, g, b: Red, green and blue color values.\n- xslant: Rotation about x-axis for 3-d text string in degrees.\n\n**real:**\n- xsize, ysize, twodim, xpos, ypos, xang, yang, zang, r, g, b, xslant\n\n**integer:**\n- i, nsav\n\n**character:**\n- *80 mesage\n\n**SEE ALSO:** SAVTXT\nDECLARATION: Subroutine INQUIR (name)\n\nFUNCTION: Inquires and prints attribute list for an item or group.\n\nPARAMETERS\n\nin: name Copy name.\n\ncharacter: name*(*)\nDECLARATION: Entry INRATG (ratgin)\n\nFUNCTION: Returns the array of rates for global animation parameters.\n\nPARAMETERS\n\nout: ratgin Array of rates for global values.\nreal: ratgin(maxfrm,11+litnum)\nDECLARATION: Entry INSPLG (onsgin)\n\nFUNCTION: Inquire on spline flag array for the look-at and look-from locations for animation.\n\nPARAMETERS\n\nout: onsgin Array of on spline flags for instances.\nreal: onsgin(maxfrm,2)\nDECLARATION: Subroutine INT4X4 (trnfm)\n\nFUNCTION: Initializes a transformation matrix to the identity matrix.\n\nPARAMETERS\n\nout: trnfm Transformation matrix initialized to the identity matrix.\n\nreal: trnfm(4,4)\nDECLARATION: Entry INTENG (tengin)\n\nFUNCTION: Returns the tension for the look-at and look-from locations for animation.\n\nPARAMETERS\n\nout: tengin Tension array.\nreal: tengin(maxprt,2)\nDECLARATION: Subroutine INTHD2\n\nFUNCTION: Initializes portions of hidden surface processor.\n\nINTHD2 should only be run before each hidden surface picture after the call to POLYS.\n\nCOMMON BLOCKS: /HIDSTF/\n\nSEE ALSO: INTHD\nDECLARATION: Subroutine INTHID\n\nFUNCTION: Initializes portions of hidden surface processor.\n\nThis routine should be run once for each hidden surface picture, before the call to polys.\n\nCOMMON BLOCKS: /CHFWAS/\n/CMEMRY/\n/HIDSTF/\n/PIXSTF/\n/KEEP/\n\nSEE ALSO: INTHD2\nDECLARATION: Subroutine INTHLR\n\nFUNCTION: Initializes the hidden line removal process.\n\n_INTHLR must be called before any other hidden line removal routine.\n\nCOMMON BLOCKS: /HIDSTF/\n /KEEP/\nDEVELOPMENT: Subroutine INTSHA (numlit, drknes)\n\nFUNCTION: Stores light number and shadow darkness for a light source.\n\nShadow darkness is linear from 0 to 1.\n\nPARAMETERS\n\nin: numlit Number of light sources being set.\ndrknes Shadow intensity between 0 and 1. A value of 0 is no shadows, a small value is a dark shadow, and a value close to 1.0 is a very light shadow.\n\nreal: drknes\n\ninteger: numlit\n\nCOMMON BLOCKS: /CHFWAS/\n/CLIMIT/\n/CHMEMRY/\nITABLE\n\nDECLARATION: Function ITABLE (r, g, b, errfac)\n\nFUNCTION: Returns the look-up table location of the color nearest the specified color.\n\nPARAMETERS\n\nian: r, g, b Component intensities of the color looked for (0.0 - 1.0).\n\nerrfac Equal to 0.0 for dithering; -0.5 all other times.\n\nout: itable The nearest location in the color look-up table.\n\nreal: r, g, b, errfac\n\ninteger: itable\nDECLARATION: Subroutine LCUC (text, nchar)\n\nFUNCTION: Converts a text string to be all upper case.\n\nPARAMETERS\n\nin: nchar Number of characters in text.\ntext Text string to be converted. The text string will be modified on return.\ninteger: nchar\n\ncharacter: text*73\nDECLARATION: Function LENTXT (text, len)\n\nFUNCTION: Determines the length of a text string.\n\nPARAMETERS\n\nin: text Text string.\n\n len The dimensioned length of the text string.\n\nout: lentxt Location of the last non-blank character in the text string.\n\ninteger: len, lentxt\n\ncharacter: text*73\n**DECLARATION:** Subroutine LITSRC (nlsrce, amount, jlocat, x, y, z)\n\n**FUNCTION:** Sets light source parameters.\n\n**PARAMETERS**\n\n- **in:**\n - nlsrce: Light source number.\n - amount: Light source intensity. If the amount is zero, the other parameters are ignored. Amount is a value between 0 and 1.0.\n - jlocat: - 0 if light source is at the eye of the observer (x,y,z are ignored).\n - 1 if one light source is at infinity (x,y,z are components of a vector pointing from the origin in the light source direction).\n - 2 if the light source is at the user-defined position (x,y,z are the coordinates of the light source position).\n - x: x coordinate of light source.\n - y: y coordinate of light source.\n - z: z coordinate of light source.\n\n- **real:** amount, x, y, z\n- **integer:** nlsrce, jlocat\n\n**COMMON BLOCKS:**\n/CHFWAS/\n/CLIMIT/\n/CMEMRY/\n\n**SEE ALSO:** INQLIT\nDECLARATION: Subroutine LODCOL (ipart, prtcol, colors)\n\nFUNCTION: Loads color information for part number being processed.\n\nPARAMETERS\n\nin: ipart Part number currently being processed. This number should be equivalent to the number that is passed into subroutine PIPLIN. Displacement arrows are loaded with part numbers starting at 10001.\n\nprtcol Reference array of rgb colors for each part in the picture. This array should be equivalent to the array that is passed into subroutine HIDLIN.\n\ncolors r,g,b color components of part ipart.\n\nreal: prtcol(3,*), colors(3)\n\ninteger: ipart\n\nSEE ALSO: HIDLIN\nDECLARATION: Subroutine MAPWV (sx, sy, wxmin, wymin, ivxmin, ivymin, x, y, iy)\n\nFUNCTION: Transforms world coordinates into screen coordinates.\n\nX and y coordinates should be clipped so they are visible on the screen.\n\nPARAMETERS\n\nin: sx Window to viewport scale factor in x.\nsy Window to viewport scale factor in y.\nwxmin Minimum x-coordinate for window in world.\nwymin Minimum y-coordinate for window in world.\nivxmin Minimum x viewport boundary (0 to 1).\nivymin Minimum y viewport boundary (0 to 1).\nx x world coordinates that is modified on return to x screen coordinate.\ny y world coordinates.\n\nout: iy y screen coordinate rounded to the nearest integer\n\nreal: sx, sy, wxmin, wymin, ivxmin, ivymin, x, y\n\ninteger: iy\n\nSEE ALSO: INQSCL INQPRT GETWND\nMAXMIN\n\nDECLARATION: Entry MAXMIN (npart, limprt, tm, displc, warp)\n\nFUNCTION: Finds and stores the maximum and minimum coordinates of a part.\n\nRoutine compares maximums and minimums to previous limits found from other parts processed by MAXMIN.\n\nPARAMETERS\n\nin: npart Part number to process.\nlimprt Part limits array.\ntm Transformation matrix for part npart.\ndisplc Displacement factor (if used).\nwarp Function warping value (if used).\n\nreal: tm(4,4), displc, warp(3)\n\ninteger: npart, limprt(2,maxitm)\n\nCOMMON BLOCKS: /CLIMIT/\n/MASTER/\n\nSEE ALSO: GETLIM\nDECLARATION: Subroutine MODIFY (cpynam, icode, value)\n\nFUNCTION: Modifies transformation matrix or attribute list for copy cpynam.\n\nPARAMETERS\n\nin: cpynam Copy name of instance to transform or change attribute list.\n\nicode Modification flag.\n\n- 1 if initialize copy's transformation matrix.\n- 2 if reorient copy to local axis system.\n- 3 if scale copy.\n- 4 if rotate copy.\n- 5 if translate copy.\n- 6 if clearing attribute list for copy.\n- 7 if setting polygon order for copy.\n- 8 if setting copy color.\n- 9 if setting feature angle.\n- 10 if setting shrink factor.\n- 11 if setting shading type.\n- 12 if setting shadow casting.\n- 13 if setting transparency parameters.\n- 14 if setting contour flag.\n- 15 if setting fringe flag.\n- 16 if setting diffused light intensity.\n- 17 if setting displacement factor.\n- 18 if setting post flag.\n- 19 if setting light source parameters.\n- 20 if setting warp vector.\n- 21 if setting dotted hidden lines.\n- 22 if setting node numbers flag.\n- 23 if setting element numbering flag.\n- 24 if setting local origin.\n- 25 if setting poorman flag.\n- 26 if displaying coordinate triad.\n- 27 if setting displacement vector arrows scale factor.\n\nvalue Values for transformation or attribute modifications.\n\nreal: value(*)\n\ninteger: icode\n\ncharacter: cpynam(*)\nCOMMON BLOCKS: /CHFWAS/\n/CLIMIT/\n/CMEMRY/\nDECLARATION: Subroutine MOV4X4 (a, b)\n\nFUNCTION: Copies the first matrix into the second matrix.\n\nPARAMETERS\n\nin: \na First 4x4 matrix.\nb Second 4x4 matrix.\n\nreal: a(4,4), b(4,4)\nDECLARATION: Subroutine MOVABS (ix, iy)\n\nFUNCTION: Update the current point to the specified screen coordinates.\n\nPARAMETERS\n\nin: ix, iy Screen coordinates of the desired point. (0.0) is the lower left point of the screen.\n\ninteger: ix, iy\nDECLARATION: Subroutine MUL4X4 (a, b, c)\n\nFUNCTION: Performs the matrix multiply, \\( a \\times b = c \\).\n\nPARAMETERS\n\n- **in:** a \\( \\) First 4x4 matrix.\n- b \\( \\) Second 4x4 matrix.\n\n- **out:** c \\( \\) Resulting 4x4 matrix.\n\n- **real:** \\( a(4,4), b(4,4), c(4,4) \\)\n\nSEE ALSO: INT4X4\nMOV4X4\nDECLARATION: Entry NEWGRP (numgru)\n\nFUNCTION: Sets up a new active group.\n\nPARAMETERS\n\n in: numgru Group number of new active group.\n\n integer: numgru\n\nSEE ALSO: GETAGR\nDECLARATION: Subroutine NORMAL (nedges, coords, xcentr, xn, contst)\n\nFUNCTION: Calculates normals at nodes of polygon.\n\nWARNING: The coordinate array should close the polygon.\n\nPARAMETERS\n\nin: \n nedges Number of vertices in polygon.\n coords Coordinate array for polygon.\n xcentr Coordinate array of center point.\n\nout: \n xn Normal array for polygon.\n contst .TRUE. if polygon is concave.\n\nreal: \n xn(3,*), coords(3,*), xcentr(3)\n\ninteger: \n nedges\n\nlogical: \n contst\nDECLARATION: Subroutine NORMTM (tm, tmnorm)\n\nFUNCTION: Normalize the columns of a transformation matrix.\n\nPARAMETERS\n\nin: tm A transformation matrix.\n\nout: tmnorm A normalized transformation matrix.\n\nreal: tm(4,4), tmnorm(4,4)\n\nSEE ALSO: PIPSRC\nDECLARATION: Subroutine NORVEC (vector)\n\nFUNCTION: Normalize a vector.\n\nPARAMETERS\n\nin: vector The vector to be normalized.\nreal: vector(3)\nNRMAVE\n\nDECLARATION: Subroutine NRMAVE (nedges, polnor, avenor)\n\nFUNCTION: Computes the average normal of all the normals of a polygon.\n\nPARAMETERS\n\nin:\n nedges Number of vertices of the polygon.\n polnor Unaveraged normal array for polygon nodes (assumed to be unit normals).\n\nout:\n avenor Average unit normal of the polygon.\nreal: polnor(3,nedges), avenor(3)\ninteger: nedges\nDECLARATION: Subroutine OPNFIL (prmpt, pstrng, fileid, stat, acc, frm, irec, iunit, ierror)\n\nFUNCTION: Opens a disk file.\n\nPARAMETERS\n\nin: \nprmpt .TRUE. if filename should be prompted for.\n .FALSE. if fileid should be used as the filename.\npstrng Character string containing prompt.\nfileid Character file id if prompt = .FALSE.\nstat Status of the file to be opened. Must be an allowable file status, such as 'old', 'new', 'scratch' or any other allowable status.\nacc Access of the file to be opened. Must be 'sequential', or 'direct'.\nfrm Format of the file to be opened. Must be an allowable file format, such as 'formatted', 'unformatted', or 'binary'.\nirec Record length for direct access files.\n\nout: \niunit Device logical number of file opened.\nierror Error flag.\n -1 if OPNFIL was run successfully.\n -0 if OPNFIL was not run successfully.\n\ninteger: irec, iunit, ierror\nlogical: prmpt\ncharacter: fileid(*), pstrng(*), stat(*), frm(*), acc(*)\nDECLARATION: Subroutine OUTBOX (npart, tm, atribt)\n\nFUNCTION: Displays a bounding box around part npart.\n\nPARAMETERS\n\nin: npart Part number to display bounding box around.\n tm Transformation matrix.\n atribt Part attribute list information for part npart.\n\nreal: tm(4,4), atribt(*)\n\ninteger: npart\n\nCOMMON BLOCKS: /CHFWAS/\n /CLIMIT/\n /CMEMRY/\n /MASTER/\n /CATTRI/\nDECLARATION: Subroutine PCHECK (nedge, xx, nornew, jconn, jpoint, numply)\n\nFUNCTION: Divides a concave polygon into numply convex polygons.\n\nIt is possible that warped concave polygons will not result in a division into convex polygons.\n\nPARAMETERS\n\nin: nedge Number of sides in original polygon.\nnornew Normals at the nodes of the original polygon.\nxx Coordinate array of concave polygon.\n\nout: jconn Connectivity of convex polygons.\njpoint Array of number of edges in new convex polygons.\nnumply Number of polygons after subdivision.\n\nreal: xx(3,*)\n\ninteger: jconn(vertmx+1,*), jpoint(vertmx+1), nedge, numply, nornew\nDECLARATION: Subroutine PERDST\n\nFUNCTION: Sets window based on perspective angle and distance.\n\nSHOULD ONLY BE CALLED IF AUTOCENTER IS NOT ON.\n\nShould be called if in perspective mode, after you have modified either the distance or perspective angle.\nDECLARATION: Subroutine PIPLIN (sx, sy, ivxmin, ivymin, wxmin, wxmax, wxmin, wymax, zmin, zmax, oldcor, polnor, oldfun, nodes, npolab, tm, atribt, nedges, ipart)\n\nFUNCTION: Transforms, clips, and maps polygons to screen coordinates, and outputs lines and polygons in line drawing mode. If hidden line is on, PIPLIN will store polygons and lines for further processing.\n\nPARAMETERS\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>sx</td>\n<td>Window to viewport scale factor in x direction.</td>\n</tr>\n<tr>\n<td>sy</td>\n<td>Window to viewport scale factor in y direction.</td>\n</tr>\n<tr>\n<td>wxmin</td>\n<td>Minimum x window coordinate.</td>\n</tr>\n<tr>\n<td>wxmax</td>\n<td>Maximum x window coordinate.</td>\n</tr>\n<tr>\n<td>wymin</td>\n<td>Minimum y window coordinate.</td>\n</tr>\n<tr>\n<td>wymax</td>\n<td>Maximum y window coordinate.</td>\n</tr>\n<tr>\n<td>zmin</td>\n<td>Distance from eye to near clipping plane.</td>\n</tr>\n<tr>\n<td>zmax</td>\n<td>Distance from eye to far clipping plane.</td>\n</tr>\n<tr>\n<td>polcor</td>\n<td>The coordinates of the polygon/line.</td>\n</tr>\n<tr>\n<td>tm</td>\n<td>Transformation matrix (This transformation matrix will also transform coordinates from world to eye system).</td>\n</tr>\n<tr>\n<td>atribt</td>\n<td>Part attribute information for line or polygon.</td>\n</tr>\n<tr>\n<td>nedges</td>\n<td>Number of vertices in current polygon or line.</td>\n</tr>\n<tr>\n<td>nodes</td>\n<td>Array of node numbers for the polygon used for labeling.</td>\n</tr>\n<tr>\n<td>npolab</td>\n<td>Polygon label number.</td>\n</tr>\n<tr>\n<td>ipart</td>\n<td>Part number that line or polygon came from. Used for hidden line removal.</td>\n</tr>\n<tr>\n<td>ivxmin</td>\n<td>Left viewport screen coordinate x.</td>\n</tr>\n<tr>\n<td>ivymin</td>\n<td>Bottom viewport screen coordinate y.</td>\n</tr>\n<tr>\n<td>oldcor</td>\n<td>The coordinates of the line or polygon.</td>\n</tr>\n<tr>\n<td>polnor</td>\n<td>Normals of the polygon. Used with the feature option during hidden line.</td>\n</tr>\n<tr>\n<td>oldfun</td>\n<td>Scalar function values at the vertices. Used for contours.</td>\n</tr>\n</tbody>\n</table>\nreal: sx, sy, wxmin, wymin, wxmax, wymax, zmin, zmax,\npolcor(3, vertmx+1), tm(4,4), atribt(*), ivxmin, ivymin,\noldcor(3, vertmx+1), polnor(3, vertmx+1), oldfun(vertmx+1)\n\ninteger: nedges, nodes, npolab, ipart\n\nCOMMON BLOCKS: /DEVI/\n/CATTRI/\n/CFLAGS/\n\nSEE ALSO: PIPSRC\nINQSCL\nINQPRT\nGETWND\nINQNT\nGETCLP\nNORMAL\nDECLARATION: Subroutine PIPSRC (sx, sy, ivxmin, ivymin, wxmin, wxmax, wymin, wymax, zmin, zmax, numvrt, polcor, polnor, polfun, tm, tmnorm, atribt, shdlen, shdmin, shdmax)\n\nFUNCTION: Transforms, clips and maps to screen coordinates, and stores polygons for later processing by the hidden surface processor.\n\nPARAMETERS\n\nin: sx Window to viewport scale factor in x direction.\n sy Window to viewport scale factor in y direction.\n wxmin Minimum x window coordinate.\n wxmax Maximum x window coordinate.\n wymin Minimum y window coordinate.\n wymax Maximum y window coordinate.\n zmin Distance from eye to near z clipping plane.\n zmax Distance from eye to far z clipping plane.\n numvrt Number of vertices in this polygon.\n polcor Coordinates of the polygon.\n tm Transformation matrix. (This transformation matrix will also transform coordinates from world to eye system.)\n atribt Attribute information for the polygon.\n shdlen Shadow length.\n tmnorm Normalized transformation array.\n ivxmin Left viewport screen coordinate x.\n ivymin Bottom viewport screen coordinate y.\n polnor Normals of the polygon.\n warped .TRUE. if checking for warped polygons on edge.\n polfun Polygon function values.\n\nreal: tm(4,4), atribt(*), polcor(3,*), polnor(3,*), sx, sy, wxmin, wymin, wymax, zmin, zmax, tmnorm(4,4), ivxmin, ivymin, polfun(*), shdlen\n\ninteger: numvrt\n\nlogical: warped\nCOMMON BLOCKS: /DEVI/ /CATTRI/ /CFLAGS/\n\nSEE ALSO: PIPLIN INQSCCL INQPRT GETWND INQFRN GETCLP NORMAL PCHECK NORMTM\nDEPLOYMENT: Subroutine POLFIL (nedges, ix, iy, r, g, b)\n\nFUNCTION: Draws a filled polygon.\n\nPARAMETERS\n\nin: nedges Number of edges in polygon to be output.\nix,iy Screen coordinate arrays of the polygon.\nr,g,b Color components (0.0 - 1.0) of the polygon.\n\nreal: r, g, b\n\ninteger: nedges, ix, iy\nSubroutine POLSTA (nedges, coords, wxmin, wxmax, wymin, \nwwmax, polxmx, polxmin, polymx, polymn, \nistat)\n\nGets polygon maximums, minimums, and status (for x and y). \n\nAll coordinates are in the eye coordinate system.\n\nin: nedges Number of vertices in the polygon or line.\ncoors Coordinate array for vertices.\nwxmin Minimum x window coordinate.\nwxmax Maximum x window coordinate.\nwymin Minimum y window coordinate.\nwymax Maximum y window coordinate.\n\nout: istat Status of the polygon.\n = 1 if trivially accept.\n = 2 if trivially reject.\n = 3 if must clip the polygon.\npolxmx Maximum polygon x coordinate.\npolxmin Minimum polygon x coordinate.\npolymax Maximum polygon y coordinate.\npolymn Minimum polygon y coordinate.\nreal: wxmin, wxmax, wymin, wymax, polxmx, polymn, polymx, polymn,\ncoors (3,nedges)\n\ninteger: nedges, istat\n\nSEE ALSO: CLPPZE\n CLPPOL\n CLPLIN\n ZPLSTA\nDECLARATION: Subroutine POLYS (npart, limits, tm, atribt)\n\nFUNCTION: Takes all polygons in part npart, does pre-processing (such as smooth shading and vector arrows) and dumps them into the appropriate pipeline.\n\nPARAMETERS\n\nin: npart Part number to process.\n limits Part limits array.\n tm Transformation matrix.\n atribt Part attribute list for part npart.\n\nreal: atribt(*), tm(*,*)\n\ninteger: npart, limits\n\nCOMMON BLOCKS: /CATTRI/\n /CLIMIT/\n /CHFWAS/\n /MASTER/\n /MEMRY/\n\nSEE ALSO: PIPLIN\n PIPSRC\n**DECLARATION:** Subroutine PORMAN (nedges, coords, order, plot)\n\n**FUNCTION:** Determines if polygons are front or back facing, then flags back facing polygons for elimination.\n\n**PARAMETERS**\n\n**in:**\n- nedges Number of vertices for this polygon.\n- coords Coordinate information for this polygon.\n- order Polygon ordering flag.\n - 0. if poorman is not on for the polygon being processed.\n - 1. if clockwise element ordering.\n - 2. if counterclockwise element ordering.\n\n**out:**\n- plot If .TRUE., the polygon is front facing and therefore visible.\n\n**real:** coords(3,nedges), order\n\n**integer:** nedges\n\n**logical:** plot\nDECLARATION: Subroutine PROMPT (txt)\n\nFUNCTION: Outputs a character string to the display device.\n\nPARAMETERS\n\nin: txt Character string that contains the required prompt.\n\ncaracter: txt*80\nDECLARATION: Subroutine PRSPC (coord)\n\nFUNCTION: Transforms point to perspective viewing.\n\nPARAMETERS\n\nin: coord x,y,z coordinate of point to transform according to perspective. The coordinates of the point are modified on return.\n\nreal: coord(3)\n\nCOMMON BLOCKS: /VEWSTF/\n\nSEE ALSO: PRSSTF\n**DECLARATION:** Subroutine PRSSTF\n\n**FUNCTION:** Sets up perspective parameters according to the look-at and look-from point.\n\n*PRSSTF be called after the look-at and look-from point have been established, and before any calls to PRSPC, PIPLIN, or PIPSRC.*\n\n**COMMON BLOCKS:** /VEWSTF/\n\n**SEE ALSO:** PRSPC PIPLIN PIPSRC\nDECLARATION: Subroutine PURGE (cpynam)\n\nFUNCTION: Removes a call to an instance wherever listed in the hierarchical data structure.\n\nPARAMETERS\n\nin: cpynam Instance name to be deleted.\n\nclass: cpynam(*)\nDECLARATION: Subroutine PVEC (point, ctm, dis, sx, sy, ivxmin, ivymin, wxmin, wymin, wxmax, wymax, zmin, zmax, zrange, polfun, atribt, node, npart, ipc)\n\nFUNCTION: Creates and outputs displacement arrows.\n\nPARAMETERS\n\nin: point Coordinates at base of arrow.\n dis Displacement array at point.\n sx Window to viewport scale factor in x.\n sy Window to viewport scale factor in y.\n ivxmin Left viewport screen, x coordinate.\n ivymin Bottom viewport screen, y coordinate.\n wxmin Minimum x window coordinate.\n wxmax Maximum x window coordinate.\n wymin Minimum y window coordinate.\n wymax Maximum y window coordinate.\n zmin Distance from eye to near z clipping plane.\n zmax Distance from eye to far z clipping plane.\n zrange Distance between z clipping planes.\n polfun Polygon function values.\n atribt Attribute list of polygon containing point.\n node Vertex number of point in polygon.\n npart Part number of polygon containing point.\n ipc Arrow part number.\n ctm Transformation matrix for polygon containing point.\n\nreal: point(3), ctm(4,4), dis(3), sx, sy, ivxmin, ivymin, wxmin, wymin, wxmax, wymax, zmin, zmax, zrange, polfun(*), atribt(*)\n\ninteger: ipc, node, npart\n\nCOMMON BLOCKS: /CATTRI/\n /CHFWAS/\n /CMEMRY/\nDECLARATION: Subroutine RDINIT\n\nFUNCTION: Initializes the graphics device, and initializes the common block /RESOLT/.\n\nCOMMON BLOCKS: /RESOLT/\nDECLARATION: Subroutine READMV (geofil, funfil, dspfil)\n\nFUNCTION: Reads MOVIE.BYU files for database definition.\n\nREADMV may be called many times.\n\nPARAMETERS\n\nin: geofil Geometry file name.\nfunfil Function file name.\ndspfil Displacement file name.\n\ncharacter: geofil(*), funfil(*), dspfil(*)\n\nCOMMON BLOCKS: /CHFWAS/\n/CLIMIT/\n/CMEMRY/\n\nChapter Two TECHNICAL REFERENCES 2.130\nDECLARATION: Entry REDCHK (filnam)\n\nFUNCTION: Reads a checkpoint file.\n\nAll database descriptions defined by you before a REDCHK call will be deleted, because the checkpoint file will overwrite the existing database.\n\nPARAMETERS\n\nin: filnam The name of the file to be read in for database definition.\n\ncharacter: filnam(*)\n\nSEE ALSO: WRTCHK\nDECLARATION: Subroutine RESET\n\nFUNCTION: Initializes the global transformation matrix.\n\nSEE ALSO: INQGLB\nSETGLB\nROTATE\nSCALE\n**DECLARATION:** Subroutine ROTATE (rx, ry, rz)\n\n**FUNCTION:** Performs global rotate about a right handed coordinate system.\n\n**PARAMETERS**\n\n- **in:**\n - rx: Rotation about the x-axis in degrees.\n - ry: Rotation about the y-axis in degrees.\n - rz: Rotation about the z-axis in degrees.\n\n- **real:** rx, ry, rz\n\n**SEE ALSO:**\n- RESET\n- SETGLB\n- SCALE\n- INQGLB\nDECLARATION: Subroutine RPLCOP (sordex, ctm, atlist)\n\nFUNCTION: Replaces transformation and attribute information for an instance.\n\nPARAMETERS\n\nin: sordex The instance sort number.\n ctm Transformation matrix for the instance.\n atlist Attribute list for the instance.\n\nreal: atlist(maxatt), ctm(4,4)\n\ninteger: sordex\n\nCOMMON BLOCKS: /CHFWAS/\n /CLIMIT/\n /CMEMRY/\n\nSEE ALSO: EXTCOP\nDECLARATION: Subroutine RPLGLB (glb4x4, glbatt)\n\nFUNCTION: Sets global attributes to those in the list coming in.\n\nPARAMETERS\n\nin: glb4x4 Global transformation matrix.\n glbatt Global attribute array, defined as follows:\n\n1 - Red background intensity (0-1).\n2 - Green background intensity (0-1).\n3 - Blue background intensity (0-1).\n4 - Window x minimum (world coordinate).\n5 - Window x maximum (world coordinate).\n6 - Window y center (world coordinate).\n7 - Perspective angle (degrees).\n8 - Distance.\n9 - X look-from point.\n10 - Y look-from point.\n11 - Z look-from point.\n12 - X look-at point.\n13 - Y look-at point.\n14 - Z look-at point.\n15 - Near z clipping plane.\n16 - Far z clipping plane.\n17 - X minimum viewport (0-1).\n18 - X maximum viewport (0-1).\n19 - Y center viewport (0-1).\n20 - Near fog plane.\n21 - Far fog plane.\n22 - Light number.\n23 - Light location flag.\n24 - Light intensity.\n25 - X position for light.\n26 - Y position for light.\n27 - Z position for light.\n22 - 27 are repeated for each light source.\n\nreal: glb4x4(4,4), glbatt(*)\n\nCOMMON BLOCKS: /CHFWAS/\n /CMEMRY/\nDECLARATION: Subroutine RUNANI (begfrm, endfrm, ierr)\n\nFUNCTION: Runs the animation.\n\nPARAMETERS\n\nin: \n- begfrm Beginning point to start animation (keyframe.subframe).\n- endfrm Ending point to end animation (keyframe.subframe).\n\nout: \n- ierr Error flag.\n - 0 if the animation was run successfully.\n - 1 if the animation was not run successfully.\n\ncharacter: begfrm*10, endfrm*10\n\nCOMMON BLOCKS: /CMEMRY/\n/DEVII/\n/CLIMIT/\n/CHFWAS/\nDECLARATION: Entry SAVTXT (mesage, xsize, ysize, twodim, xpos, ypos, zpos, xang, yang, zang, r, g, b, xslant, n, nsav)\n\nFUNCTION: Saves text string attributes.\n\nPARAMETERS\n\nin:\n- n: Text string number.\n- mesage: The text string array.\n- xsize: X dimension factor.\n- ysize: Y dimension factor.\n- twodim: If .TRUE., message is 2-D. .False., 3-D text strings.\n- xpos: X position of text string in world coordinate.\n- ypos: Y position of text string in world coordinate.\n- zpos: Z position of text string in world coordinate.\n- xang: X directional vector.\n- yang: Y directional vector.\n- zang: Z directional vector or angle of text string if in 2-d mode.\n- r, g, b: Red, green and blue color values.\n- xslant: Rotation about x-axis for 3-d text string in degrees.\n\nout:\n- nsav: Total number of stored messages.\n\nreal: xsize, ysize, twodim, xpos, ypos, xang, yang, zang, r, g, b, xslant\n\ninteger: n, nsav\n\ncharacter: mesage(80)\n\nSEE ALSO: INQTXT\nDECLARATION: Subroutine SCALE (sx, sy, sz)\n\nFUNCTION: Performs global scale.\n\nPARAMETERS\n\nin: sx Scaling in the x direction.\nsy Scaling in the y direction.\nsz Scaling in the z direction.\n\nreal: sx, sy, sz\n\nSEE ALSO: RESET\n ROTATE\n SETGLB\n INQGLB\nDECLARATION: Entry SETBGC (red, green, blue)\n\nFUNCTION: Set background color.\n\nAll values are from 0 to 1. Values are adjusted to those actually found in the color look-up table (if one is being used).\n\nPARAMETERS\n\nin: red Red intensity of background color.\ngreen Green intensity of background color.\nblue Blue intensity of background color.\n\nSEE ALSO: SETLUT ITABLE INQBGCC\nDECLARATION: Entry SETBOX (npart, cormax, cormin)\n\nFUNCTION: Stores the x, y, z limits of a part.\n\nPARAMETERS\n\nin: npart Part number.\ncormax Maximum x, y, and z coordinates of box.\ncormin Minimum x, y, and z coordinates of box.\n\nreal: cormax(3), cormin(3)\n\ninteger: npart\n\nSEE ALSO: INQBOX\nDECLARATION: Entry SETCLP (znear, zfar)\n\nFUNCTION: Sets z clip information.\n\nPARAMETERS\n\nin: \nznear Distance from eye to nearest z clipping plane. \nzfar Distance from eye to farthest z clipping plane.\n\nreal: znear, zfar\n\nSEE ALSO: GETCLP\nDECLARATION: Entry SETCNT (iflag)\n\nFUNCTION: Sets number of contour levels.\n\nPARAMETERS\n\nin: iflag Number of contour levels to be displayed.\ninteger: iflag\n\nSEE ALSO: INQCNT\nDECLARATION: Subroutine SETCOL (r, g, b, errfac)\n\nFUNCTION: Updates the current color to the specified color.\n\nPARAMETERS\n\nin: r, g, b New color components (0.0 - 1.0).\n errfac Equal to 0.0 for dithering; - 0.5 all other times.\n\nreal: r, g, b, errfac\nSETCON\n\nDECLARATION: Entry SETCON (key, sordex, thecnt)\n\nFUNCTION: Sets instance continuity at a keyframe for animation.\n\nPARAMETERS\n\nin: key Key frame number.\n sordex Sort index number of the instance.\n thecnt The continuity value at keyframe key.\n\nreal: thecnt\n\ninteger: key, sordex\n\nSEE ALSO: INQCON\nDECLARATION: Entry SETDEF (numcol, red, grn, blu)\n\nFUNCTION: Sets the red, green, and blue color components of color number numcol. All color values are from 0 to 1.\n\nPARAMETERS\n\nin: numcol Color number (1 to 6).\n red Red intensity of default color number numcol.\n grn Green intensity of a default color number numcol.\n blu Blue intensity of a default color number numcol.\n\nreal: red, grn, blu\n\ninteger: numcol\n\nSEE ALSO: GETDEF\nDECLARATION: Entry SETDSP (xvec, yvec, zvec)\n\nFUNCTION: Sets the displacement direction cosine components that will be used with displacement fringes or contours.\n\nPARAMETERS\n\n- `in`: xvec X component of direction vector.\n yvec Y component of direction vector.\n zvec Z component of direction vector.\n\n- `real`: xvec, yvec, zvec\n\nSEE ALSO: INQDSP\nDECLARATION: Entry SETDST (dist)\n\nFUNCTION: Sets the distance from the eye to the look at point.\n\nSETDST is only valid when software is in perspective angle mode, and when auto center is off. The function of this routine can also be obtained by adjusting the look-from point.\n\nPARAMETERS\n\nin: dist Distance from eye to look-at point.\nreal: dist\n\nCOMMON BLOCKS: /VEWSTF/\n\nSEE ALSO: INQDST\nATFROM\nINQFLG\nDECLARATION: Entry SETFLG (cflag, lflag)\n\nFUNCTION: Sets global flags.\n\nPARAMETERS\n\nin: cflag Key to what is being set, which is one of the following:\n\n'ALIA' Anti-aliasing flag.\n'SHDO' Shadow flag.\n'AXLS' Axis are to be drawn.\n'BOUN' Draw bounding box instead of model.\n'BORD' Draw border.\n'CENT' Auto center flag.\n'COLO' Draw colored lines.\n'DISP' Displacements are performed.\n'DITH' Dithering status.\n'ELEM' Element labeling status.\n'FOUR' Four view status.\n'GLAS' Transparency status.\n'HAZE' Haze/fog option.\n'HIDD' Hidden line status.\n'LABEL' Label contours flag.\n'LEGE' Display contour legend.\n'NODE' Node labeling status.\n'ONED' Warped polygons on edge status.\n'OVER' Overlay status.\n'PERA' Perspective or windowing toggle status.\n'PERS' Perspective/orthographic status.\n'POLY' Polygon clipping performed.\n'POOR' Poorman status.\n'SHAD' Shaded images status.\n'SYMM' Symmetric contours or fringes status.\n'VECT' Vector arrows status.\n'WARP' Function warping status.\n'TEXT' Text display status.\n'TK41' Tektronix 4129 hardware status.\n'LABV' Label for views status.\n'PLYF' Polygon fill shaded images status.\n\niflag .TRUE. or .FALSE. status of cflag.\n\nout: lflag .TRUE. or .FALSE. status of cflag.\n\nlogical: iflag\n\ncharacter: cflag(*)\n\nCOMMON BLOCKS: /CFLAGS/\n\nSEE ALSO: INQFLG\nDECLARATION: Entry SETFNC (nlevel, valmin, valmax)\n\nFUNCTION: Sets the number of color fringes to be used, and the minimum and maximum range for fringes.\n\nPARAMETERS\n\nin: nlevel Number of function levels to be used.\n valmin Minimum value of color fringe.\n valmax Maximum value of color fringe.\n\nreal: valmin, valmax\n\ninteger: nlevel\n\nSEE ALSO: INQFNC\nSETFOG\n\nDElaration: Entry SETFOG (dist1, dist2)\n\nFunction: Sets the distance to the nearest and farthest fog planes.\n\nParameters\n\nin: dist1 Distance from eye to nearest fog plane.\n dist2 Distance from eye to farthest fog plane.\n\nreal: dist1, dist2\n\nSee Also: INQFOG\nDECLARATION: Entry SETFRN (iflag)\n\nFUNCTION: Sets number of fringe levels to be displayed.\n\nPARAMETERS\n\nin: iflag Number of fringe levels to be displayed.\n\ninteger: iflag\n\nSEE ALSO: INQFRN\nDECLARATION: Entry SETGLB (tm)\n\nFUNCTION: Saves the transformation matrix that is to be used as the global matrix.\n\nPARAMETERS\n\nin: tm Transformation matrix.\nreal: tm(4,4)\n\nSEE ALSO: INQGLB\n ROTATE\n SCALE\n RESET\nDECLARATION: Subroutine SETLIN (cstyle)\n\nFUNCTION: Updates the current linestyle to solid or dashed.\n\nPARAMETERS\n\nin: cstyle Desired linestyle:\n = 'd' for dashed.\n = 's' for solid.\n\ncharacter: cstyle(*)\nDECLARATION: Subroutine SETLUT (table).\n\nFUNCTION: Loads the color look-up table.\n\nPARAMETERS\n\nin: table The desired look-up table. The default is 'c', which is for a full color-ramped look-up table.\n\ncharacter: table(*)\nDECLARATION: Subroutine SETMOD (mode)\n\nFUNCTION: Sets the display device to either graphics or alpha mode.\n\nPARAMETERS\n\nin: mode The specified mode:\n - 'graphics' to put device in graphics mode.\n - 'alpha' to put device in alpha mode.\n\ncharacter: mode(*)\nDECLARATION: Entry SETPER (setang)\n\nFUNCTION: Sets the perspective angle to the value specified.\n\nSETPER can only be called if the software is in the perspective angle mode.\n\nPARAMETERS\n\nin: setang Perspective angle to be set in degrees.\nreal: setang\n\nSEE ALSO: INQPER\n INQFLG\nDECLARATION: Entry SETPRT (xmin, xmax, ycen)\n\nFUNCTION: Sets viewport boundaries.\n\nSETPRT calculates minimum and maximum y values enforcing a one-to-one aspect ratio. All coordinates are normalized from 0 to 1. SETPRT checks for illegal input, and will set the viewport to the entire screen if illegal input is detected.\n\nPARAMETERS\n\nin: xmin Minimum x coordinate for viewport.\n xmax Maximum x coordinate for viewport.\n ycen Center y coordinate for viewport.\n\nreal: xmin, xmax, ycen\n\nCOMMON BLOCKS: /RESOLT/\n\nSEE ALSO: INQPRT\n\nSAMPLE CALL: Call SETPRT (0,-5,-75)\nCall sets up a viewport in the upper quarter of the screen.\nDECLARATION: Entry SETRAT (key, sordex, therat)\n\nFUNCTION: Sets instance rate at a keyframe for animation.\n\nPARAMETERS\n\nin: key Frame number.\nsordex Sort index number of instance.\ntherat The rate value at keyframe key.\n\nreal: therat\n\ninteger: key, sordex\n\nSEE ALSO: INQRAT\nDECLARATION: Entry SETREF (ncolor, colfnc)\n\nFUNCTION: Sets function value reference colors.\n\nPARAMETERS\n\nin: ncolor Number of reference colors to be used.\ncolfnc Array of colors at each function level.\n\nreal: colfnc (3,maxlev)\n\ninteger: ncolor\n\nSEE ALSO: INQREF\nDECLA**RATION**: Entry SETSCL\n\n**FUNCTION**: Sets window to viewport scale factors.\n\n*SETSCL must be called before a call to INQSCL.*\n\n**COMMON BLOCKS**: /RESOLT/\n\n**SEE ALSO**: SETPRT\nINQPRT\nGETWND\nSETWND\nINQSCL\nDECLARATION: Subroutine SETSCN (iy, ixbeg, ixend, r, g, b, errfac)\n\nFUNCTION: Sends a segment of a scanline to the graphics screen.\n\nThe graphics device must be in graphics mode before this routine can be called.\n\nPARAMETERS\n\nin: iy Y value of scanline.\nixbeg Beginning x value of segment.\nixend Ending x value of segment.\nr, g, b Color arrays for scanline segment.\nerrfac Equal to 0.0 for dithering; - 0.5 all other times\n\nreal: r(0:ixres), g(0:ixres), b(0:ixres), errfac\n\ninteger: iy, ixbeg, ixend\n\nCOMMON BLOCKS: /RESOLT/\nDECLARATION: Entry SETSPL (key, sordex, thespl)\n\nFUNCTION: Sets instance on spline flags for animation.\n\nPARAMETERS\n\nin:\nkey Key frame number.\nsordex Sort index number of the instance.\nthespl The spline flag:\n = 0 for no spline.\n = 1 for spline.\n\nreal: thespl\n\ninteger: key, sordex\n\nSEE ALSO: INQSPL\nDECLARATION: Entry SETSTD\n\nFUNCTION: Sets standard function reference colors.\nSETSUB\n\nDECLARATION: Entry SETSUB (keyfrm, number)\n\nFUNCTION: Sets number of subframes between keyframes.\n\nPARAMETERS\n\nin: keyfrm Beginning keyframe number.\n number Number of subframes.\n\ninteger: keyfrm, number\n\nSEE ALSO: INQSUB\nDECLARATION: Entry SETTEN (key, sordex, thenen)\n\nFUNCTION: Sets instance tension at a keyframe for animation.\n\nPARAMETERS\n in: key Key frame number.\n sordex Sort index number of the instance.\n thenen Tension value at keyframe key.\n real: thenen\n integer: key, sordex\n\nSEE ALSO: INQTEN\nDECLARATION: Entry SETWND (xmin, xmax, ycen)\n\nFUNCTION: Sets window bounds.\n\nSETWND calculates minimum and maximum y values enforcing a one-to-one aspect ratio.\n\nPARAMETERS\n\nin: xmin Minimum x world coordinate for window.\n xmax Maximum x world coordinate for window.\n ycen Center y world coordinate for window.\n\nreal: xmin, xmax, ycen\n\nCOMMON BLOCKS: /RESOLT/\n\nSEE ALSO: GETWND\nDECLARATION: Subroutine SHRINK (shrk, nedges, polcor, xcentr)\n\nFUNCTION: Moves the nodes of a polygon toward the polygon center.\n\nThe coordinate array should close the polygon.\n\nPARAMETERS\n\nin: \n shrk Shrink factor:\n 0 = no shrink.\n 1 = full shrink.\n nedges Number of polygon vertices.\n polcor Coordinate array for polygon.\n xcentr Coordinate array of polygon's center point.\n\nreal: \n shrk, polcor(3,nedges), xcentr(3)\n\ninteger: \n nedges\nDECLARATION: Entry SMOCLR (nodbeg, nodend)\n\nFUNCTION: Clears the smooth shading routine.\n\nSMOCLR should be called for each part that is smooth shaded.\n\nPARAMETERS\n\nin: nodbeg Node to begin smooth shading.\nnodend Node to end smooth shading.\n\ninteger: nodbeg, nodend\n\nSEE ALSO: SMOSTR\n SMOGET\n**SMOGET**\n\n**DECLARATION:** Entry SMOGET (nedges, nodes, polnor)\n\n**FUNCTION:** Retrieves the smooth normals for a polygon.\n\nUse SMOGET after all of the polygons in a part have been processed with SMOSTR.\n\n**PARAMETERS**\n\n- **in:**\n - nedges Number of edges in the polygon.\n - nodes Array of node numbers for the polygon.\n\n- **out:**\n - polnor Smooth normal of each polygon vertex.\n\n- **real:**\n - polnor(3,nedges)\n\n- **integer:**\n - nodes(nedges), nedges\n\n**SEE ALSO:** SMOSTR SMOCLR\nDECLARATION: Entry SMOSTR (nedges, nodes, polnor)\n\nFUNCTION: Averages normals for smooth shading.\n\nCall SMOCLR before making any calls to SMOSTR.\nYou should call SMOSTR for each polygon in a part.\n\nPARAMETERS\n\nin: nedges Number of edges in the polygon being smoothed.\n nodes Array of node numbers for the polygon.\n polnor Normal of each polygon vertex.\n\nreal: polnor(3,nedges)\n\ninteger: nodes(nedges), nedges\n\nSEE ALSO: SMOCLR\n SMOGET\nSTCONG\n\nDECLARATION: Entry STCONG (key, icode, thecnt)\n\nFUNCTION: Sets continuity value for spline animation of look-at or\nlook-from point.\n\nPARAMETERS\n\nin: key Keyframe number.\n icode 1 = look at point, 2 = look from point.\n thecnt The continuity value at keyframe key (-1 to 1).\n\nreal: thecnt\n\ninteger: key, icode\nDECLARATION: Subroutine STOREL (ipart, nedges, polcor, polnor, polfun, \nnodes, npolab, atribt)\n\nFUNCTION: Loads a polygon for hidden line removal.\n\nINTHLR must be called previous to calling STOREL. HIDLIN should be called after all polygons have been processed with STOREL.\n\nPARAMETERS\n\nin: ipart Part number this polygon comes from.\nnedges Number of edges in the polygon.\nnumpol Polygon number currently being processed.\npolcor Screen coordinates of the polygon.\npolnor Polygon normals at the vertices.\npolfun Polygon scalar values at the vertices.\nnodes Node number array for the vertices.\nnpolab Polygon label number.\natribt Part attribute list information for the polygon.\n\nreal: polcor(3,*), polnor(3,*) , polfun(*), atribt(*)\n\ninteger: numpol, nedges, nodes(*)\n\nCOMMON BLOCKS: /CATTRI/ \n/HIDSTF/ \n/KEEP/ \n\nSEE ALSO: INTHLR \nHIDLIN\n**DECLARATION:** Entry STRATG (key, icode, therat)\n\n**FUNCTION:** Sets rate for global animation at keyframes.\n\n**PARAMETERS**\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>key</td>\n<td>Keyframe number.</td>\n</tr>\n</tbody>\n</table>\n| icode | Key to which global animation parameter is being set: \n 1 - Global scales. \n 2 - Global rotates. \n 3 - Background color. \n 4 - Window. \n 5 - Perspective angle. \n 6 - Distance. \n 7 - Look-from point. \n 8 - Look-at point. \n 9 - Z clipping planes. \n 10 - Viewport. \n 11 - Fog planes. \n 12 - Light #1. \n 13 - Light #2. \n Continued for each light source. |\n| therat | The rate value at keyframe key (0 to 1). |\n| real | thespl |\n| integer | key, icode |\n**DECLARATION:** Entry STSPLG (key, icode, thespl)\n\n**FUNCTION:** Sets on spline flag for look-at or look-from point spline animation.\n\n**PARAMETERS**\n\n- **in:**\n - `key` Keyframe number.\n - `icode` 1 = look-at point, 2 = look-from point.\n - `thespl` The spline value at keyframe key (0 or 1).\n\n- **real:** `thespl`\n\n- **integer:** `key`, `icode`\nSTTENG\n\nDECEPTION: Entry STTENG (key, icode, theten)\n\nFUNCTION: Sets tension values for spline animation for look-at or look-from point.\n\nPARAMETERS\n\nin: key Key frame number.\n icode 1 = look-at point, 2 = look-from point.\n theten The tension value at keyframe key (-1 to 1).\n\nreal: theten\n\ninteger: key, icode\n\nSEE ALSO: INTENG\nDECLARATION: Subroutine SUMMRY\n\nFUNCTION: Displays the global attributes set.\n\nCOMMON BLOCKS: /CLIMIT/\n/DEVI/\n/VEWSTF/\n/RESOLT/\nCOMMON BLOCKS: /CATTRI/\n/CFLAGS/\n/CLIMIT/\n/VEWSTF/\nDECLARATION: Subroutine TEXT (mesage, xsize, ysize, twodim, xpos, ypos, zpos, xang, yang, zang, r, g, b, atribt, xslant, glbflg, ierr)\n\nFUNCTION: Generates and displays alphanumeric text.\n\nPARAMETERS\n\nin: mesage The text string to be displayed.\n xsize X dimension factor.\n ysize Y dimension factor.\n twodim If .TRUE., 2-D text strings are generated. If .FALSE., 3-D text strings are generated.\n xpos X position of text string in model coordinates.\n ypos Y position of text string in model coordinates.\n zpos Z position of text string in model coordinates.\n xang X directional vector coordinate.\n yang Y directional vector coordinate.\n zang Z directional vector coordinate (if 3-d).\n r, g, b Red, green, and blue color values for text string.\n atribt Attribute list.\n xslant Rotation about x-axis for 3-d text string in degrees.\n glbflg If .TRUE., xpos and ypos come in as screen coordinates.\n ierr If ierr = 1, then a character not defined in the character font has been entered.\n\nreal: xsize, ysize, xpos, ypos, zpos, xang, yang, zang, atribt(*), xslant, r, g, b\n\ninteger: ierr\n\nlogical: twodim, glbflg\n\ncharacter: mesage*80\nDECLARATION: Subroutine TMPTS (tm, coord)\n\nFUNCTION: Transforms an x,y,z point according to a transformation matrix.\n\nPARAMETERS\n\nin: tm Transformation matrix.\n coord Coordinate to be transformed. The coordinate is modified on return.\n\nreal: tm(4,4), coord(3)\nDECLARATION: Subroutine TMPTSN (tm,coord)\n\nFUNCTION: Transforms a normal vector by a transformation matrix.\n\nPARAMETERS\n\nin: tm Transformation matrix.\n coord Normal to be transformed.\n\nreal: tm(4,4), coord(3)\nDECLARATION: Subroutine TRAVRS (root, itask, sgorit, grsort, trndex, sgrcnt, sitcnt, gstart, matrix, sgrind, grppttr, sortdx, grprec, stkfms, atlist, stkiaa)\n\nFUNCTION: Traverses the groups and items structure for picture processing.\n\nPARAMETERS\n\nin: root Root group to be displayed.\n itask Task flag:\n 0 = auto-center.\n 1 = process part for display.\n 2 = write out geometry file.\n sgorit Subgroup or subitem flag array.\n grsort Group sort array.\n sgrcnt Subgroup counter array.\n sitcnt Subitem counter array.\n gstart Group start array.\n matrix Instance transformation (4x4) matrixes.\n sgrind Subgroups that have been processed array.\n grppttr Group pointer at recursive level array.\n sortdx Sort index array.\n grprec Group recursion counter array.\n stkfms Stack of ctm's array.\n stkiaa Attribute stack.\n atlist Attribute list transformation index array.\n\nreal: matrix(4,4,maxins), stkfms(4,4,maxrec), atlist(maxiaa,maxins), stkiaa(maxiaa,0:maxrec)\n\ninteger: sgorit(maxins), grsort(maxins), trndex(maxins), sgrcnt(maxgrp), sitcnt(maxgrp), gstart(maxgrp), sgrind(maxrec), grppttr(maxrec), sortdx(maxrec), grprec(maxgrp), itask, root\nCOMMON BLOCKS: /CATTRI/ \n/CHFWAS/ \n/CHEMRY/ \n/DEVI/ \n/VEWSTF/\nDECLARATION: Entry TXTDIS\n\nFUNCTION: Displays existing text strings.\n\nSEE ALSO: GENTXT\nTXTINT\nDECLARATION: Entry TXTINT\n\nFUNCTION: Initializes the text string routines.\n\nSEE ALSO: TXTDIS\n GENTXT\nDEPLOYMENT: Subroutine WARPOL (nedges, tmpcor, tmpnor, iconn, ipoin, numpol)\n\nFUNCTION: Subdivides warped polygons that are partly front and partly back facing to the observer.\n\nPARAMETERS\n\nin: \nnedges Number of vertices in the polygon.\n\ntmpcor Coordinate array of warped polygon.\n\ntmpnor Normals array of warped polygon.\n\nout: \niconn Connectivity array after subdivision of warped polygon.\n\nipoin Number of vertices in each subdivided polygon.\n\nnumpol Number of polygons that the warped polygon was divided into.\n\nreal: \ntmpcor(3,*), tmpnor(3,*)\n\ninteger: \nnedges, iconn(vertmx+1,*), ipoin(*), numpol\nDECLARATION: Subroutine WRITMV (npart, limits, tm)\n\nFUNCTION: Stores geometry information for writing a geometry file.\n\nPARAMETERS\n\nin: npart Number of parts to be written to the geometry file.\nlimits Part limits array.\ntm Transformation matrix for npart.\n\nreal: limits(2,*), tm(4,4)\n\ninteger: npart\n\nCOMMON BLOCKS: /MASTER/\n\nSEE ALSO: WRTDRV\nWRTGEO\nDECLARATION: Entry WRTCHK (filnam)\n\nFUNCTION: Writes a checkpoint file.\n\nPARAMETERS\n\nin: filnam The name of the file to be used as the checkpoint file.\n\ncharacter: filnam(*)\n\nSEE ALSO: REDCHK\nDECLARATION: Entry WRTDRV (geonam)\n\nFUNCTION: Opens file and initializes variables for a geometry file write.\n\nPARAMETERS\n\n in: geonam Name of the geometry file to be written.\n character: geonam(*)\n\nSEE ALSO: WRTGEO\nDECLARATION: Entry WRTGEO\n\nFUNCTION: Writes out the geometry file after a tree traversal.\n\nSEE ALSO: WRTDRV\nSubroutine ZPLSTA (nedges, coords, zmin, zmax, polzmx, polzmn, istat)\n\nGets polygon maximums, minimums, and status for z-clipping.\n\nAll coordinates are in the eye coordinate system.\n\nParameters:\n\n- **in:**\n - **nedges:** Number of vertices in the polygon or line.\n - **coords:** Coordinate array for vertices.\n - **zmin:** Distance to nearest clipping plane.\n - **zmax:** Distance to farthest clipping plane.\n\n- **out:**\n - **istat:** Status of the polygon:\n - -1 if trivially accept.\n - -2 if trivially reject.\n - -3 if must clip the polygon.\n - **polzmx:** Maximum polygon z coordinate.\n - **polzmn:** Minimum polygon z coordinate.\n\n- **real:**\n - **coords,** **zmin,** **zmax,** **polzmx,** **polzmn,** **coords** (3,nedges)\n\n- **integer:**\n - **nedges,** **istat**\n\nSee also:\n\n- CLPPZE\n- CLPPOL\n- CLPLIN\n- POLSTA\nThis chapter describes all of the common blocks used in the Raster Graphics Subroutine Package. They are listed in alphabetical order. For each common block, each variable is defined, and the routines accessing the common block are listed.\n\nInformation about common blocks is included so you will be aware of common coupled routines. For some applications, you will need to set up the common blocks before an application can call the subroutines that use them.\n\n**Common Blocks for Internal Use ONLY**\n\nThree common blocks are strictly for internal use. For these common blocks, we have only given the declaration. These common blocks are:\n\n/HIDSTF/\n/PIXSTF/\n/ZBUFER/\n\nMake sure you don't use these common block names in subroutines you supply yourself.\n\nIf you want more information about these common blocks, contact the Engineering Computer Graphic Lab at Brigham Young University. The address is in Appendix C.\nCOMMON BLOCK: /CATTRI/ (IORDER, IDFFUS, ICOLOR, INNODE, INPOLY, IFEATR, ISHRNK, IWARP, ICONTR, IDASHL, ISHADE, ISHADO, IGLASS, IFRNGE, ILIGHT, IDSPLC, IPOST, IFAST, IDRWAX, IAXORG, IROTAX, IVECTR)\n\nFUNCTION: Contains pointers into the instance attribute array. /CATTRI/ is set up in the subroutine GRAINT.\n\nPARAMETERS: Points to the:\n\ninteger:\nIORDER Polygon ordering information.\nIDFFUS Diffused light.\nICOLOR Color information.\nINNODE Node numbering flag.\nINPOLY Polygon numbering flag.\nIFEATR Feature angle.\nISHRNK Shrink factor.\nIWARP Warp vector.\nICONTR Contour information.\nIDASHL Dashed line flag.\nISHADE Shading type flag.\nISHADO Shadow flag.\nIGLASS Transparency information.\nIFRNGE Fringe flag.\nILIGHT Light information.\nIDSPLC Displacement factor.\nIPOST Post flag.\nIFAST Poorman flag.\nIDRWAX Draw local axis flag.\nIAXORG Local axis origin.\nIROTAX Local axis rotation angles.\nIVECTR Displacement vector arrows Scale factor.\nROUTINES THAT CONTAIN /CATTRI/\n\nCOLORS MODTFM\nDEFAUT OUTBOX\nDEFPRT PIPLIN\nDSPTXT PIPSRC\nGLBAXS POLOTL\nGRAINT POLYS\nLIGHTS PVEC\nLOCAXS SHOATR\nMODATT TRAVIN\nMODFRM TRAVRS\nCOMMON BLOCK: /CFLAGS/ (POLYGN, POORMN, HIDDEN, IALIAS, DITHER, LCOLOR, FOG, LCONTR, LFRING, LGlass, LS, SHADW, PERSPC, WARPED, LABNOD, Labele, FSTHID)\n\nFUNCTION: Contains system global flags.\n\nPARAMETERS\n\nPARAMETERS\n\n.logical:\n\n.POLYGN\n\nPolygonal data.\n\n.POORMN\n\nPoorman.\n\n.HIDDEN\n\nHidden line removal.\n\n.IALIAS\n\nAnti-aliasing.\n\n.DITHER\n\nDithering\n\n.LCOLOR\n\nColored lines.\n\n.FOG\n\nFog/haze.\n\n.LCONTR\n\nContours.\n\n.LFRING\n\nFringes.\n\n.LGLASS\n\nTransparency.\n\n.LSHADW\n\nShadows.\n\n.PERSPC\n\nPerspective.\n\n.WARPED .TRUE. if checking for warps on edge polygons.\n\n.LABNOD\n\nNode labeling.\n\n.Labele\n\nElement labeling.\n\n.FSTHID\n\nPolygon fill.\n\nROUTINES THAT CONTAIN /CFLAGS/\n\n<table>\n<thead>\n<tr>\n<th>CHKPTNT</th>\n<th>EDGSHD</th>\n<th>PAINT</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>COLORS</td>\n<td>FLAGIT</td>\n<td>PIPLIN</td>\n</tr>\n<tr>\n<td>DEBSOR</td>\n<td>FOURVW</td>\n<td>PIPSRC</td>\n</tr>\n<tr>\n<td>DISALL</td>\n<td>GLBAXS</td>\n<td>POLOTL</td>\n</tr>\n<tr>\n<td>DSPTXT</td>\n<td>INTSEC</td>\n<td>POLOUT</td>\n</tr>\n<tr>\n<td>EDGMAK</td>\n<td>LOCAXS</td>\n<td>PREALI</td>\n</tr>\n<tr>\n<td>EDGMKP</td>\n<td>MAKSHA</td>\n<td>SEGGEN</td>\n</tr>\n</tbody>\n</table>\n\nChapter Three COMMON BLOCKS 3.4\nCOMMON BLOCK: /CHFWAS/ (ILSINT, ILSLOC, ILSXYZ, ILSNEW, ISHDIN, IPRCOL, ICOPIN, ITRNDE, ISGORI, IGRPDE, ISGITO, IGRSOR, IGRUPA, ICHIDA, IORGPA, ISORDX, INCOPY, INPL, IALIST, IMATRI, ISGRCN, ISITCN, IGSTAR, ITSGIC, ISGRIN, IGRPPT, ISORTD, IGRPRE, ISTKFM, IAASTK, IGRNAM, ITMNAM, ICPNAM, IPSTFL, IFWANI, IANIGL)\n\nFUNCTION: Contains pointers into memory.\n\nPARAMETERS\n\nPoints to the:\n\ninteger: ILSINT Light source intensities.\nILSLOC Light source location flags.\nILSXYZ Light source coordinates.\nILSNEW Modified light source coordinates.\nISHDIN Shadow intensities.\nIPRCOL Part color array used in the hidden line removal algorithm.\nICOPIN Instance copies.\nITRNDE Transformation index.\nISGORI Child numbers.\nIGRPDE Parent group.\nISGITO Child flag array.\nIGRSOR Group sort array.\nIGRUPA Root group array.\nICHIDA Child array.\nIORGPA Item or group flag array.\nISORDX Sort array.\nINCOPY Copy number.\nINPL Part limit array.\nIALIST Instance attribute lists.\nIMATRI Instance transformation matrices.\nISGRCN Subgroup counter array.\nISITCN Subitem counter array.\nIGSTAR Group start array.\nITSGIC Child test array.\nISGRIN Subgroup counter array.\nIGRPFT Group pointer array.\nISORTD Recursion sort index array.\nIGRPRE Group recursion test array.\nISTUFM Transformation stack array.\nIAASTU Attribute stack array.\nIGRNAM Group names array.\nITMNAM Item names array.\nICPNAM Instance names array.\nIPSTFL Instance post flag array.\nIFWANI Starting unit number for instance animation.\nIANIGL Unit number for global animation.\n\nROUTINES THAT CONTAIN /CHFWAS/\n\n<table>\n<thead>\n<tr>\n<th>ADDCOL</th>\n<th>GETITM</th>\n<th>INTHD</th>\n<th>PURGE</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ADDFRM</td>\n<td>GLBACT</td>\n<td>INTID</td>\n<td>PVEC</td>\n</tr>\n<tr>\n<td>ANIDRV</td>\n<td>GRAINT</td>\n<td>INTSHA</td>\n<td>READMV</td>\n</tr>\n<tr>\n<td>BEGANI</td>\n<td>HIDSUR</td>\n<td>LITSRC</td>\n<td>REDGLB</td>\n</tr>\n<tr>\n<td>CLRANI</td>\n<td>HUDGRP</td>\n<td>MAKSHA</td>\n<td>RPLCOP</td>\n</tr>\n<tr>\n<td>COLORS</td>\n<td>HUDITM</td>\n<td>MODIFY</td>\n<td>RPLCOR</td>\n</tr>\n<tr>\n<td>COPNUM</td>\n<td>HUCOP</td>\n<td>NEWANI</td>\n<td>RPLGLB</td>\n</tr>\n<tr>\n<td>DISALL</td>\n<td>HUGSOR</td>\n<td>OPWANI</td>\n<td>RUNANI</td>\n</tr>\n<tr>\n<td>FRMONE</td>\n<td>HUSORT</td>\n<td>OUTBOX</td>\n<td>SHOATR</td>\n</tr>\n<tr>\n<td>GETATT</td>\n<td>HUSTA</td>\n<td>POLYS</td>\n<td>TRAVIN</td>\n</tr>\n<tr>\n<td>GETCOP</td>\n<td>INQLIT</td>\n<td>POSFRM</td>\n<td>TRAVRS</td>\n</tr>\n<tr>\n<td>GETGRU</td>\n<td>INQUIR</td>\n<td>PRGRUN</td>\n<td>WRTGLB</td>\n</tr>\n</tbody>\n</table>\nCOMMON BLOCK: /CLIMIT/ (MAXITM, MAXINS, MAXGRP, MAXMEM, MAXNOD, MAXPOL, MAXVER, MAXREC, MAXUSE, MAXCAL, MAXCHR, MAXIAA, MAXLIT, NP, NJ, NPT, NCON, NPNEW)\n\nFUNCTION: Contains system limits.\n\nPARAMETERS\n\ninteger: MAXITM Maximum number of items allowed.\nMAXINS Maximum number of instances allowed.\nMAXGRP Maximum number of groups allowed.\nMAXMEM Maximum amount of memory allocated.\nMAXNOD Maximum number of nodes allowed.\nMAXPOL Maximum number of polygons allowed.\nMAXVER Maximum number of vertices allowed.\nMAXREC Maximum number of recursion levels allowed.\nMAXUSE Maximum amount of memory in use.\nMAXCAL Maximum number of links in tree structure.\nMAXCHR Maximum number of characters in a name.\nMAXIAA Maximum number of words in an attribute list.\nMAXLIT Maximum number of lights.\nNP Number of parts read in.\nNT Number of nodes read in.\nNPT Number of polygons read in.\nNCON Number of nodes in connectivity list.\nNPNEW New number of parts found following tree traversal.\n### Routines That Contain `/CLIMIT/`\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ACTIVE</td>\n<td>DISALL, HUPITM, MAKSHA, RPLCOR</td>\n</tr>\n<tr>\n<td>ADDCAL</td>\n<td>DSPTXT, HUSOR, MODATT, RPLCOP</td>\n</tr>\n<tr>\n<td>ANILIT</td>\n<td>EXTCOP, INILIT, MODIFY, RUNANI</td>\n</tr>\n<tr>\n<td>BEGANI</td>\n<td>FRMONE, INITGI, MODTFM, SHDHEX</td>\n</tr>\n<tr>\n<td>CATIAA</td>\n<td>GEOMOV, INTCAL, OUTBOX, SHOATR</td>\n</tr>\n<tr>\n<td>CHKPNT</td>\n<td>GLBAXS, INTSHA, POLYS, SUMMRY</td>\n</tr>\n<tr>\n<td>DEFAALT</td>\n<td>GRAINT, LIGHTS, PRCRUN, TRAVIN</td>\n</tr>\n<tr>\n<td>DEFINE</td>\n<td>HUACAL, LIMITS, PURGE, TRAVRS</td>\n</tr>\n<tr>\n<td>DEFPRT</td>\n<td>HUDCAL, LITSRC, READMV, TRVCOP</td>\n</tr>\n<tr>\n<td>DELETE</td>\n<td>HUPGRP, LOCAXS, REDLIT, WRTLIT</td>\n</tr>\n</tbody>\n</table>\nCOMMON BLOCK: /CMEMRY/ (MEMORY(MXMEM))\n\nFUNCTION: Contains the data base for the program.\n\nYou should use /CHFWAS/ as pointers into memory to extract information.\n\nPARAMETERS\n\ninteger/real: MEMORY The data base.\n\nROUTINES THAT CONTAIN /CMEMRY/\n\nADDCAL GETGRU INQUIR PURGE\nADDFRM GETITM INTHDP PVEC\nANIDRV GLBACT INTHID READMV\nBEGANI GRAINT INTSHA REDGLB\nCHKPNT HIDSUR LITSRC RPLCOP\nCLRANI HUDGRP MAKSHA RPLCOR\nCOLORS HUDITM MODIFY RPLGLB\nCOPNUM HUGCOP NEWANI RUNANI\nDISALL HUGSOR OPNANI SHOATR\nEXTCOP HUSORT OUTBOX TRAVIN\nFRMONE HUSSTA POLYS TRAVRS\nGETATT INQLIT POSFRM WRTGLB\nGETCOP\n\nChapter Three COMMON BLOCKS 3.9\nIn the hidden algorithm:\n\n**COMMON BLOCK: /HIDSTF/**\n\n(EDGPNT, IOFFST, IBUCKY, IFREE, SHDPNT, IOFSHD, ISHADO, ISHADY, IAVAIL)\n\nIn the hidden line algorithm:\n\n**COMMON /HIDSTF/**\n\n& IPOLST(MAXPOL+1),\n& XHOLD(MAXEDG),\n& YHOLD(MAXEDG),\n& ZHOLD(MAXEDG),\n& CCONT(MAXEDG),\n& NODNUM(MAXEDG),\n& SURF(11,MAXPOL),\n& PGRID(3,MAXCOR),\n& JNUMBR(MAXCOR),\n& JVECLS(2,MAXVEC),\n& JVECVP(MAXVEC),\n& JVTYPE(MAXVEC),\n& VECTOR(9,MAXVEC),\n& JVP(4,MAXVEC),\n& JXYS(MXGRID,MXGRID,MXBVAR),\n& JXIV(MXGRID,MXGRID,MXBVEC),\n& XLINE(4,MAXSEG)\n\n**FUNCTION:** For internal use for the hidden line and hidden surface algorithms.\n\n*If you want more information on this common blocks should contact The Engineering Computer Graphics Lab. Brigham Young University.*\n\n**ROUTINES THAT CONTAIN HIDSTF:**\n\n<table>\n<thead>\n<tr>\n<th>ROUTINE</th>\n<th>ROUTINE</th>\n<th>ROUTINE</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CLENUP</td>\n<td>HIDSUR</td>\n<td>LBLNOD</td>\n</tr>\n<tr>\n<td>DEBSOR</td>\n<td>HSHEDG</td>\n<td>LODCNT</td>\n</tr>\n<tr>\n<td>DMPVEC</td>\n<td>HSHNOD</td>\n<td>LODINA</td>\n</tr>\n<tr>\n<td>EDGMKP</td>\n<td>INTHD2</td>\n<td>LODSHD</td>\n</tr>\n<tr>\n<td>GENCNT</td>\n<td>INTHDP</td>\n<td>PREALI</td>\n</tr>\n<tr>\n<td>GLSSRT</td>\n<td>INTHID</td>\n<td>SEGGEN</td>\n</tr>\n<tr>\n<td>HIDLIN</td>\n<td>INTHLR</td>\n<td>UPDATE</td>\n</tr>\n<tr>\n<td>HIDSRP</td>\n<td>LBLELE</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nCOMMON BLOCK: /KEEP/ (NUMPOL, NUMPLS)\n\nFUNCTION: Contains the internal polygon numbers for opaque and shadow polygons used for hidden surface and line removal.\n\nPARAMETERS\n\ninteger: NUMPOL Internal opaque polygon number.\nNUMPLS Internal shadow polygon number.\n\nROUTINES THAT CONTAIN /KEEP/\n\nHIDLIN\nINTHLR\nINTHDP\nINTHID\nPOLOUT\nSHDOUT\nCOMMON BLOCK: /MASTER/ (COORDS, ICONEC, NUMVRT, FUNVAL, DSPVAL)\n\nFUNCTION: Contains geometric information.\n\nPARAMETERS\n\nreal: COORDS Coordinate Array.\ninteger: ICONEC Connectivity Array.\n NUMVRT Number of vertices in each polygon array.\nreal: FUNVAL Function values at the nodes.\n DSPVAL Displacement values at the nodes.\n\nROUTINES THAT CONTAIN /MASTER/\n\nCHKPNT\nGEOMOV\nLIMITS\nOUTBOX\nPOLYS\nSUMMARY\nWRITMV\nCOMMON BLOCKS: /PIXSTF/ (IBUCKX, IFREEX)\n\nFUNCTION: For internal use in the hidden surface removal algorithm during anti-aliasing.\n\nIf you want more information on this common block, contact Engineering Computer Graphics Lab, Brigham Young University.\n\nROUTINES THAT CONTAIN /PIXSTF/\nALIGLS\nDEBSOR\nINTHID\nSTRPIX\nCOMMON BLOCK: /RESOLT/ (IXRES, IYRES)\n\nFUNCTION: Contains the x and y resolution of the display device.\n\n/RESOLT/ is set up in RDINIT.\n\nPARAMETERS\n\ninteger: IXRES The x resolution of the display device. Resolution starts at zero, so a device with 1024 pixels should have IXRES = 1023.\n\nIYRES The y resolution of the display device.\n\nROUTINES THAT CONTAIN /RESOLT/\n\nCENTER HIDSUR SUMMRY\nCHKPNT LODINA VEWPRT\nFOURVW LODSHD WINDOW\nGLBAXS PAINT WRTGLB\n**COMMON BLOCK:** \n/VEWSTF/ (AT, FROM, ZO, VIEWMT)\n\n**FUNCTION:**\nContains the viewing parameters.\n\n**PARAMETERS**\n\n- **real:**\n - AT: The look-at point.\n - FROM: The look-from point.\n - ZO: The distance to the perspective projection plane.\n - VIEWMT: The viewing transformation matrix.\n\n**ROUTINES THAT CONTAIN /VEWSTF/**\n\n- ATFROM\n- CENTER\n- CHKPT\n- DSGTXT\n- GLBAXS\n- GRAINT\n- INQLAF\n- INTLIT\n- PRSPC\n- PRSTF\n- SHDCTR\n- SHDHEX\n- TRAVRS\nCOMMON BLOCK: /ZBUFER/ IBUF\n\nFUNCTION: For internal use in the hidden surface algorithm.\n\nIf you want more information on this common block, contact Engineering Computer Graphics Lab, Brigham Young University.\n\nROUTINES THAT CONTAIN /ZBUFER/\n\nALIGLS\nCLRBUF\nDEBSOR\nINSESEG\nPAINT\nSHADOW\nChapter Four\n\nINCLUDE FILES\n\nThis chapter explains the content of each of the include files needed for the Raster Graphics Display Library. The include files contain parameters controlling site and global control, which you should edit to fit your needs.\n\nThe subroutine package performs error checking on all arrays that are dimensioned by the parameters in the include files. Error messages will refer you to specific parameters in an include file.\nINCLUDE BLOCK: ANIM.INC (MAXFRM, ISTART, ISTGLB, MAXCOM)\n\nFUNCTION: Contains the variables that define parameters for animation.\n\nPARAMETERS\n\nMAXFRM The maximum number of key frames that can be defined.\n\nISTART Starting logical unit number for disk access for instance animation.\n\nISTGLB Logical unit number for disk access for global animation.\n\nMAXCOM The maximum number of commands defining a key frame.\n\nROUTINES THAT USE ANIM.INC.\n\nANIDRV\nCHKPNT\nCTRLGL\nDOSPLN\nGETATT\nMODGLB\nMOVMTN\nOPNANI\nPOSFRM\nRUNANI\nSPLNGL\nINCLUDE BLOCK: CVER.INC (VERTMX)\n\nFUNCTION: Contains the variable that defines the maximum number of vertices in a polygon.\n\nPARAMETERS\n\nVERTMX The maximum number of vertices in a polygon.\n\nROUTINES THAT CONTAIN CVER.INC.\n\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Routine</th>\n<th>Routine</th>\n<th>Routine</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CHECK</td>\n<td>GLBAXS</td>\n<td>PIPLIN</td>\n<td>SHDHEX</td>\n</tr>\n<tr>\n<td>CLPLZE</td>\n<td>HIDSUR</td>\n<td>PIPSRC</td>\n<td>SHDOUT</td>\n</tr>\n<tr>\n<td>CLPPOL</td>\n<td>LINSEC</td>\n<td>POLYS</td>\n<td>SHDTRN</td>\n</tr>\n<tr>\n<td>CLPPZE</td>\n<td>LOCAKS</td>\n<td>PRESUR</td>\n<td>SPLITP</td>\n</tr>\n<tr>\n<td>DSPTXT</td>\n<td>MAKSHA</td>\n<td>PROCHL</td>\n<td>STACK</td>\n</tr>\n<tr>\n<td>GRAINT</td>\n<td>OUTBOX</td>\n<td>ROLL</td>\n<td>TESTP</td>\n</tr>\n<tr>\n<td>GENCNT</td>\n<td>PCHECK</td>\n<td>SEND</td>\n<td>WARPOL</td>\n</tr>\n</tbody>\n</table>\nINCLUDE BLOCK:\n\nFNCT.INC (MAXLEV, MXCLEV, MXCSEG)\n\nFUNCTION:\n\nContains variables that control fringes and contours.\n\nThe software will print error messages if these parameters are exceeded.\n\nPARAMETERS\n\nMAXLEV Maximum number of function levels that can be defined for fringes and contours.\n\nMXCLEV Maximum number of separate contour strings at the same contour level.\n\nMXCSEG Maximum number of contour vectors in a contour level.\n\nROUTINES THAT CONTAIN FNCT.INC:\n\nAFNCTN DRVTXT LODCNT\nCHKPNT FRNBAR ORDCNT\nCNTBAR FUNCTN PRGRUN\nCOLORS GENCNT PROCHL\nDMPVEC HIDLIN PVEC\nINCLUDE BLOCK: HIDN.INC (IAVVRT, MAXPOL, MAXEDG, MAXCOR, MAXVEC, MXGRID, MXBSUR, MTABLE, MXRESX, MXRESY, MAXFRC, MAXFIL, LITCST, NUMSHD)\n\nFUNCTION: Contains the variables defining maximums for picture processing.\n\nPARAMETERS\n\nIAVVRT Average number of vertices in a polygon (approximate).\n\nMAXPOL Maximum number of polygons in the scene. MAXPOL is used in the visible line and surface algorithms. Regular line drawings are not affected.\n\nMAXEDG Maximum number of edges in the scene. MAXEDG is defined to be MAXPOL*IAVVRT.\n\nMAXCOR Maximum number of vertices (nodes) in the scene.\n\nMAXVEC Maximum number of line segments in the scene. MAXVEC is used for hidden line removal.\n\nMXGRID Maximum number of grid cells in X and Y. MXGRID is used for hidden line removal.\n\nMXBSUR Maximum number of polygons in a bucket. MXBSUR is used for hidden line removal.\n\nMTABLE Maximum length of the hashing table. MTABLE is used for hidden line removal.\n\nMXRESX Maximum resolution of the display device in the x direction.\n\nMXRESY Maximum resolution of the display device in the y direction.\n\nMAXFRC Maximum number of pixel fractions on a scan line for anti-aliasing. MAXFRC is used by the hidden surface algorithm.\n\nMAXFIL Length of the array used for the painters hidden surface algorithm.\n\nLITCST Maximum number of lights casting shadows.\n\nNUMSHD Maximum number of shadow polygons that must be stored in the shadow edge list array.\nROUNINES THAT CONTAIN HIDN.INC.\n\nANTALI DMPVEC\nCLENUP EDG MKP\nCLRBUF FRNBAR\nDEBSOR\n\n(cont.) HIDN.INC\nINCLUDE BLOCK: MOVL.INC (IOUT, IIN, LUN, LUN1)\n\nFUNCTION: Contains logical unit numbers for file access.\n\nPARAMETERS\n\nIOUT Logical unit numbers for writing to the terminal.\nIIN Logical unit number for reading from the terminal.\nLUN Logical unit number for disk file access.\nLUN1 Another logical unit number for disk file access.\n\nROUTINES THAT CONTAIN MOVL.INC.\n\nGETXT\nOPNFILE\nPROMPT\nINCLUDE BLOCK: MSTR.INC (MXNODE, MAXCON, MXPOLY, LITNUM, ITMNUM, INSNUM, IGRPNM, IRECNM, MAXPRT, MAXATT, MXMEM, CONST)\n\nFUNCTION: Contains the variables that define system wide parameters.\n\nPARAMETERS\n\nMXNODE Maximum number of coordinates that can be read into the data base.\nMAXCON Maximum number of nodes in the connectivity list that can be read into the data base.\nMXPOLY Maximum number of polygons that can be read into the data base.\nLITNUM Maximum number of light sources that can be defined.\nITMNUM Maximum number of items that can be defined. This corresponds to the maximum number of parts that can be defined.\nINSNUM Maximum number of instances that can be defined.\nIGRPNM Maximum number of groups that can be defined.\nIRECNM Maximum number of levels in the hierarchical tree structure.\nMAXPRT Maximum number of parts in the scene.\nMAXATT Length of the attribute list for an instance.\nMXMEM Length of the array containing the data base.\nCONST A constant to generate standard ASCII numbers for characters.\n<table>\n<thead>\n<tr>\n<th>Routine</th>\n<th>Function</th>\n<th>Function</th>\n<th>Function</th>\n<th>Function</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ADDCAL</td>\n<td>DRVTXT</td>\n<td>HIDSUR</td>\n<td>MAKSHA</td>\n<td>REDGLB</td>\n</tr>\n<tr>\n<td>ADDFRM</td>\n<td>DSPTXT</td>\n<td>HUDGRP</td>\n<td>MODFRM</td>\n<td>REDONE</td>\n</tr>\n<tr>\n<td>ANIDRV</td>\n<td>EXTCP</td>\n<td>HUDITM</td>\n<td>MODIFY</td>\n<td>RPLCP1</td>\n</tr>\n<tr>\n<td>BEGANI</td>\n<td>EXTCP1</td>\n<td>HUGCOP</td>\n<td>MOVMT</td>\n<td>RPLGLB</td>\n</tr>\n<tr>\n<td>BNDDBX</td>\n<td>FOURVW</td>\n<td>HUSROR</td>\n<td>NEWANI</td>\n<td>RUNANI</td>\n</tr>\n<tr>\n<td>CKKPNT</td>\n<td>FRNBAR</td>\n<td>HUSORT</td>\n<td>OPNANI</td>\n<td>SHOATR</td>\n</tr>\n<tr>\n<td>CLRANI</td>\n<td>GEOMOV</td>\n<td>HUSTA</td>\n<td>OUTBOX</td>\n<td>SPLNGL</td>\n</tr>\n<tr>\n<td>CNTBAR</td>\n<td>GETATT</td>\n<td>INQLIT</td>\n<td>POLYS</td>\n<td>SUMMRY</td>\n</tr>\n<tr>\n<td>COLORS</td>\n<td>GLBACT</td>\n<td>INQUIR</td>\n<td>POSFRM</td>\n<td>TRAVIN</td>\n</tr>\n<tr>\n<td>COPNUM</td>\n<td>GETCOP</td>\n<td>INTHDP</td>\n<td>PROCHL</td>\n<td>TRAVRS</td>\n</tr>\n<tr>\n<td>DISALL</td>\n<td>GETGRU</td>\n<td>INTSHA</td>\n<td>PURGE</td>\n<td>WRITMV</td>\n</tr>\n<tr>\n<td>DMPVEC</td>\n<td>GETITM</td>\n<td>LIMITS</td>\n<td>PVEC</td>\n<td>WRTGLB</td>\n</tr>\n<tr>\n<td>DOSPLN</td>\n<td>GRAINT</td>\n<td>LITSR</td>\n<td>READMEV</td>\n<td>WRTONE</td>\n</tr>\n</tbody>\n</table>\n\nChapter Four INCLUDE FILES 4.9\nUSER.INC\n\nFUNCTION: Contains the variables defining the length of character strings for user responses and database names.\n\nPARAMETERS\n\nLNSIZE The maximum length of an input character string.\n\nMXCHAR The maximum length of a data base name.\n\nROUTINES THAT CONTAIN USER.INC.\n\nGRAINT\nSHOATR\n\nChapter Four INCLUDE FILES 4.10\nAppendix A\n\nLINK MAP\n\nThis chapter contains the link map for MOVIE.BYU version 6. MOVIE.BYU is a general purpose computer graphics display system that uses RGDIL software. The purpose of this chapter is to aid users that do not have library utilities on their computers.\n\nThe link map shows which routines call other routines, and is in the following form:\n\n\\[\n\\begin{align*}\n\\text{ROUTINE1} \\\\\n\\text{ROUTINE2} \\\\\n\\phantom{\\text{ROUTINE1}} \\text{ROUTINE3} \\\\\n\\phantom{\\text{ROUTINE1}} \\text{ROUTINE4} \\\\\n\\phantom{\\text{ROUTINE1}} \\text{ROUTINE2}* \\\\\n\\phantom{\\text{ROUTINE1}} \\text{ROUTINE3}\n\\end{align*}\n\\]\n\nHere, the program flows in the following way:\n\n1. ROUTINE1 calls ROUTINE2.\n2. ROUTINE2 calls ROUTINE3.\n3. ROUTINE3 does not call anything, and returns to ROUTINE2 when finished.\n4. ROUTINE2 calls ROUTINE4.\n5. ROUTINE4 does not call anything, and returns to ROUTINE2 when finished.\n6. ROUTINE2 when finished returns to ROUTINE1.\n7. ROUTINE1 calls ROUTINE2 again. The calls that ROUTINE2 makes have already been defined, so the line is tagged with a *.\n8. ROUTINE2 when finished returns to ROUTINE1.\n9. ROUTINE1 calls ROUTINE3. ROUTINE3 has been defined previously, but does not call any other routines; therefore, ROUTINE3 is shown without the *.\n10. ROUTINE3 when finished returns to ROUTINE1, which when finished terminates the program.\n\nMOVIE.BYU contains several routines that are not part of the subroutine library. Be aware that this link map is not for you to actually use—it is just for looking.\nGTUTRN\nMUL4X4\nPIPLIN *\nMUL4X4\nMOV4X4\nGTUTRN\nCATIAA\nDEFPRT *\nHRDWAR\nWRITMV\nPOLYS\nINQCNT\nINQFRN\nGETWND\nGETCLP\nISHDDS\nINQSCL\nINQPRT\nAROCLR\nSMOCLR\nINQARP\nHRDWAR\nINQDSP\nCNTRPT\nNORMAL\nSMOSTR\nSMOGET\nSHRINK\nNORMTM\nMOV4X4\nNORVEC\nPCHECK\nSTACK\nPUSH\nNRMAVE\nNORVEC\nLOKROT\nINT4X4\nMUL4X4\nTMPTS\nTESTP\nPOPP\nNORANG\nCHECK\nSEND\nROLL\nPUSH\nSEND\nNORANG\nLINSEC\nBOX\nSPLITP\nPUSH\nROLL *\nSEND\nTMPTS\nTMPTSN\nHRDWAR\nPIPSRC\nTMPTS\nTMPTSN\nWARPOL\nCNTRPT\nPORMAN\nMAKSHA\nSHDHEX\nSHDTRN\nCLPZPE *\nPRSPC\nCLPPOL *\nSHDOUT\nMAPWV\nEDGSHD\nLODSHD\nZSTRMM\nLODSHD *\nPRSPC\nCLPPOL *\nSHDOUT *\nCLPZPE *\nPRSPC\nCLPPOL *\nNRMAVE\nPOLOUT\nCOLORS\nINQLEV\nCNTRPT\nLIGHTS\nFRINGE\nMAPWV\nEDGMKP\nEDGMAK\nLODINA\nZSTRMM\nLODINA *\nAROCHK\nPVEC\nANQSDS\nANQDSP\nARST\nARSCAL\nARROTA\nROTMAT\nMATR\nMATR\nARTRAN\nMATR\nANQLEV\nFRINGE\nSETARC\nAppendix A LINK MAP A.6\nNORMTM *\nISHDDS\nPIPSRC *\nPIPLIN *\nLODCOL\nCNTRPT\nSHRINK\nCNTRPT\nNORMAL\nTMPTS\nHRDWAR\nPIPLIN *\nAROCHK\nPVEC *\nSETARP\nOUTBOX\nGETWND\nGETCLP\nINQSCL\nINQPRT\nINQBOX\nPIPLIN *\nMOV4X4\nGTUTRN\nMUL4X4\nGTUTRN\nLOCAXS *\nMAXMIN\nTMPTS\nWRTGEO\nTMPTS\nTRAVRS *\nCENTER\nINQPER\nINQGLB\nGETLIM\nATFROM *\nMOV4X4\nGTUTRN\nMULAX4\nPRSSTF\nTMPTS\nPRSC\nSSHDDS\nSETCLP\nSETWND\nGETWND\nSHDCTR\nINQGLB\nGETLIM\nMOV4X4\nGTUTRN\nMULAX4\nTMPTS\nSSHDDS\n\nAppendix A LINK MAP A.7\nSTRPIX\nCODPS1\nSTRPIX\nCODNG1\nSTRPIX\nCODPS2\nSTRPIX\nPREALI *\nALIGLS\nSTRPIX\nSETONE\nGLASS\nINSSEG\nGETONE\nINSSEG\nSETONE\nINTSEC\nSTRPIX\nSHADOW\nANTALI\nGLASS\nINSSEG\nPAINT\nDRWABS\nMOVABS\nHAZE\nDODITH\nSETSCN\nSETCOL\nUPDATE\nCLRBUF\nCLRNXT\nFRNBAR\nINQPRT\nINQLEV\nDODITH\nSETSCN\nSETCOL\nMOVABS\nDRWABS\nINQBGC\nDSPTXT\nGETWND\nINQPRT\nINT4X4\nGTUROZ *\nMOV4X4\nINQSCCL\nGTUTRN\nINQGLB\nMOV4X4\nGTUTRN\nMUL4X4\nPAUSE *\nPIPLIN *\nDSPTXT *\nINQFRN\nMAPINZ\nZINQMM\nHIDLIN\nHSHNOD\nUHINIT\nUHPUT\nUHLOOK\nUHETOI\nUHLOOK\nHSHREDG\nUHINIT\nUHPUT *\nUHETOI *\nINQCNT\nGENCNT\nINQLEV\nORDCNT\nLODCNT\nGRIDEN\nPREVEC\nSRTVEC\nSRTLEN\nPRESUR\nSRTSUR\nSRTLEN\nPROCHL\nZINQMM\nINQCNT\nINQBGC\nINQLEV\nSETLIN\nSETCOL\nMOVABS\nDRWABS\nDSPTXT *\nSETCOL\nINQARC\nDMPVEC\nINQCNT\nINQBGC\nINQLEV\nSETLIN\nSETCOL\nMOVABS\nDRWABS\nDSPTXT *\nINQARC\nLBLELE\nCHRNUM\nDISTXT\nLBLNOD\nCHRNUM\nDISTXT\nCNTBAR\nINQPRT\nGETWND\nINQLEV\nINQBGC\nDSPTXT *\nSETCOL\nMOVABS\nDRWABS\nINQCNT\nHRDWAR\nTXTDIS\nINQTXT\nDSPTXT *\nSETMOD\nINQPRT\nSETMOD\nDSPTXT *\nSETPRT\nATFROM *\nDISALL *\nINQPRT\nDISALL *\nGETXT *\nGETCOM\nLCUC\nREADMV\nGEOMOV\nOPNFIL *\nBNDBOX\nSETFNC\nSETSTD\nASTSTD\nASTFNC\nSETFNC\nGETAGR\nCHRNUM\nGETITM *\nADDCAL\nGETITM *\nGETGRU *\nGETAGR\nHUACAL\nHUGCOP\nHUGC01\nHUSORT\nHUSOR1\nHUSSTA\nHUSSTI\nHUGSOR\nHUGS01\nGETCOP *\nINTCAL\nINT4X4\nGETXT *\nAppendix A LINK MAP A.13\nRPLCOP *\nSPLNGL\n INQFRM\n SPLINE\n MODGLB *\nCOMGLB\nCTRLGL\n GLBCNM\nMODFRC\nMODGLB *\nRPLGLB *\nMODFRC\nDOSPLN\n INQFRM\n SPLINE\n MODFRM *\nANICOM\nMODFRM *\nRPLCOP *\nFOURVW *\nDISALL *\nCAMERA\nMOV4X4\nSPLNGL *\nCTRLGL *\nMODFRC\nMODGLB *\nCOMGLB\nRPLGLB *\nDOSPLN *\nMODFRM *\nDOSPLN *\nMODFRM *\nANICOM\nRPLCOP *\nFOURVW *\nDISALL *\nCAMERA\nMOV4X4\nGETXT *\nWRTCHK\n OPNFIL *\nGETAGR\nINQGLB\nINQTXT\nINQPER\nGETWND\nINQFRT\nINQBGC\nGETCLP\nGETDEF\nINQBOX\nINQFNC\nANQFNC\nANQREF\nINTENG\nINSPPLG\nINCONG\nSTRATG\nSTTENG\nSTCONG\nSTSPPLG\nINRATG\nSTRATG\nRUNANI *\nSETFRM\nANIDRV *\nGETXT *\nACTGRP *\nDEFINE *\nADDCAL *\nCHKNAM\nGETXT *\nGETCOP *\nDELETE\nGETCOP *\nHUDITM\nHUGSOR *\nHUDCAL\nHUSORT *\nHUSSTA *\nHUDGRP\nHUGSOR *\nHUDCAL *\nPURGE\nGETAGR\nGETITM *\nGETGRU *\nGETCOP *\nHUPITM\nHUDITM *\nHUPITM *\nHUPGRP\nHUGSOR *\nHUGCAL *\nCHKNAM *\nMODIFY\nGETCOP *\nHUGSOR *\nANFILI\nNEWANI\nOPNANI *\nEXTCOP\nGETCOP *\nHUGSOR *\nEXTCP1\nGETCOP *\nGETAGR\nTRAVIN *\nWRTONE\nMODTFM\n\nAppendix A LINK MAP A.16\nINQDEV\nINQFRN\nSETFRN\nGETCOM *\nINQDSD\nSQUISH\nSETDSP\nSETFRN\nINQFNC\nSETFNC\nSETSTD\nINQREF\nSETREF\nSETSTD\nINQFOG\nGETCLP\nGLBACT\nSCALE\nINQGLB\nGTUSCL *\nSETGLB\nROTATE\nINQGLB\nGTUROX *\nGTUROY *\nGTUROZ *\nSETGLB\nSETBGC\nSETWND\nSETPER\nPERDST *\nSETDST\nINQLAF\nATFROM *\nPERDST *\nATFROM *\nSETCLP\nSETPRT\nLITSRC *\nSETFOG\nANFILI\nINQFRM\nGLBACT *\nINQDEV\nINQCNT\nSETCNT\nGETTXT *\nGETCOM *\nINQDSD\nSQUISH\nSETDSP\nINQFNC\nSETFNC\nSETSTD\nINQREF\n\nAppendix A LINK MAP A.18\nSETREF\nSETSTD\nSETFNC\nSETCNT\nINQBGC\nGENTXT\n INQTXT\n GETXT *\n GETCOM *\n GETNUM\n TXTINT\n SQUISSH\n SETMOD\n DSPTXT *\n SAVTXT\nINQDEV\nRESET *\nINQLAF\nINQPRT\nGETWND\nGETCLP\nINQLIT\nINTSHA\n INTSH1\nPERDST *\nINQDST *\nINQPER\nPNTHLP\n OPNFL *\n GETXT *\nGETATT *\nPNTMEN\n INQFRN\n INQcnt\nPAUSE *\nRMLEV\nTREE\nPRGRUN *\nNEXTIDX\n NEXTWD\n GETXT *\n LCUC\nRMLEV\nADLEV\nFNDIDX\nFNDCOM\nFNDIDX\nWRTCOM\nAppendix B\n\nAN INTRODUCTION TO HIERARCHAL DATA STRUCTURES\n\nIn Chapter One, Example Problems, the fifth and sixth examples refer to this chapter, \"An Introduction to Hierarchal Data Structures.\" We have included this section because reading through it will help you understand the hierarchial data structures used in RGDL.\nIf you read in a geometry file into RGDLL using READMV, the program will print a message similar to the following message:\n\nA COPY OF 1 HAS BEEN ADDED\n\nThis line with a different number will be repeated for each part the applications program reads from the given geometry file. The message indicates that the hierarchical data structure is doing some default work for you.\n\nYou may choose to ignore the hierarchical data structure, but we strongly recommend you learn how to manipulate and use this powerful tool.\n\nThis appendix defines three terms you need to know and explains the hierarchical data structure, but does not give examples. You should see Chapter One, especially Examples Five and Six, for examples of how hierarchical data structures are used within RGDLL.\n\nHierarchical Data Structure Terms\n\nItem: An item is a collection of polygons that all behave in the same way. In other words, the polygons share the same attributes and are transformed together.\n\nAn item cannot be deleted from the database and cannot carry attributes or transformations.\n\nInstance: (or copy)\n\nAn instance is a copy of an item or a group and can be deleted. It carries attributes as well as transformations.\n\nAt display time, the instances show up on the screen.\n\nGroup: A group is a collection of instances. A group, like an item, cannot be deleted from the database, and it cannot carry attributes or transformations.\n\nWhat Are Groups And Items?\n\nGroups and items are part of a powerful hierarchical data structure that allows you to create and manipulate parts that may be related to one another.\n\nA simple example of how parts can be created and manipulated is the creation of a car model. The wheels and the car body can be defined as separate items, while the wheels and car body together are a group.\n\nHalf of the car body can be modeled. This half can then be copied and mirrored to create an entire car body. A wheel can be created and replicated four times, then placed at the correct locations.\nThe body and wheels can then be manipulated together as an entire car. All four wheels can be rotated while the car is moving by simply rotating the instance containing the four wheels.\n\nUpon initialization, RGDL creates a default group called ROOT (Capital letters are different from lower case letters. Thus, a group with the name 'ROOT' will be different than another group with the name 'root'). When a geometry file is read in, a copy of each of the parts are placed under the current active group (default ROOT).\n\nThus, if a three part geometry file were read in, the structure would look like Figure 1.\n\nBecause the numbers 1, 2, and 3 are not very descriptive of the geometry, we can change the names to improve the description. For example, we can rename items 1, 2, and 3 to part1, part2, and part3, and change the instance names to copy1, copy2, and copy3. The structure will then look like Figure 2.\nBecause the numbers 1, 2, and 3 are not very descriptive of the geometry, we can change the names to improve the description. For example, we can rename items 1, 2, and 3 to part1, part2, and part3, and change the instance names to copy1, copy2, and copy3. The structure will then look like Figure 2.\n\nAs mentioned earlier, only instances can be deleted from the data structure. For example, we can delete copy1 and add another instance of part3. The resulting structure is shown in Figure 3.\nAs seen in Figure 3, item part1 has simply been unlinked from the data structure. It may be linked up at a later time under any group, or ignored.\n\nAnother group called 'NEW GROUP' can be created. Under this group, copies of other groups or items can be added.\n\nThe only limit is that the links can not be recursive. For example, a copy of 'ROOT' cannot be added under the group 'ROOT' because a circular list would be created. RGDL checks for recursive links and tells you about them.\n\nA new structure might look like Figure 4.\n\n\n\nThe term definitions explain that only instances carry transformations and attributes. Transformations concatenate up the tree; thus a rotate of copy2 and a translate of ROOT COPY 1 would result in a scene that has two rotated copy2's, but only one translated copy2 (the rotate would occur before the translate).\n\nIn fact, such a scene would contain seven parts: two each of copy2, copy3, and copy4, and one part representing copy1. The one group of copy2, copy3, and copy4 would be translated.\nAttributes such as color, shading type, and highlights are not concatenated. Instead they are inherited from \"parent\" to \"child\" for attributes not set for the child.\n\nFor example, if the color of copy2 was set to red, and the color of ROOT COPY 1 was set to green, the color of copy2 will remain red. If the color of copy3 was not set, it would be green under ROOT COPY 1 because copy3 inherited this color from its \"parent\".\n\nHowever, copy3 under ROOT COPY 2 will not inherit color on the way up the tree, but will remain with its default color. An instance that has no attribute after traversing the tree from bottom to top will be assigned a default attribute.\n\nTo better understand hierarchical data structures, study the examples shown in Chapter One, especially Examples Five and Six.\nAppendix C\nSOFTWARE Installation\n\nThe magnetic tape supplied with this document is in a PRIME Magsav format for easy installation on other PRIME systems. The magnetic tape contains the following files:\n\n- HIDDEN.F77: RGDL hidden surface routines.\n- ANIMATE.F77: RGDL animation routines.\n- GRUPIT.F77: RGDL groups and items outlines.\n- JONESD.F77: RGDL hidden line routines.\n- MAIN.F77: RGDL common use routines.\n- MOVLIB.F77: RGDL input/output library routines.\n- AED.F77: RGDL device driver routines\n The C routines are for UNIX installations. Only one driver should be linked with an application.\n- AED.C\n- RAS110.F77\n- RAS120.F77\n- RASOUT.C\n- T4010.F77\n- T4109.F77\n- T4111.F77\n- T4115.F77\n- T4129.F77\n\nRGDL include files\n\n- ANIM.INC\n- CVER.INC\n- FNCT.INC\n- HIDN.INC\n- MOVL.INC\n- MSTR.INC\n- USER.INC\n\nExample problems\n\n- RSPEX1.F77\n- RSPEX2.F77\n- RSPEX3.F77\n- RSPEX4.F77\n- RSPEX5.F77\n- RSPEX6.F77\n\nExample problem geometry file\n\n- EXP9.GEO\nINSTALLATION\n\nRGDL software is for installation on a PRIME computer. Even though the code is generic FORTRAN, it contains include file statements that are system dependent. The device drivers contain code that dumps buffers; this code is also system dependent.\n\nTo install RGDL on different operating systems, the include file statements in the source code must be modified to be compatible with your system's requirements. The code to perform system dependent buffer dumping in the device driver should also be changed.\n\nBUGS, PROBLEMS, and COMMENTS\n\nWe have done our best to make RGDL and its documentation accurate and clear. However, you may find things that need to be clarified or changed. If you find bugs or problems in the software or the documentation, please contact us. Any positive comments would also be appreciated.\n\nSoftware Manager\nEngineering Computer Graphics Lab\nCivil Engineering Department\n368 Clyde Building\nBrigham Young University\nProvo, UT 84602\n(801) 378-2812"}}},{"rowIdx":76,"cells":{"id":{"kind":"string","value":"220e807e0787adb690b2848ad3fa84ecd26fced6"},"text":{"kind":"string","value":"What is JavaScript?\n\nJavaScript is a dynamic computer programming language. It is lightweight and most commonly used as a part of web pages, whose implementations allow client-side script to interact with the user and make dynamic pages. It is an interpreted programming language with object-oriented capabilities.\n\nJavaScript was first known as LiveScript, but Netscape changed its name to JavaScript, possibly because of the excitement being generated by Java. JavaScript made its first appearance in Netscape 2.0 in 1995 with the name LiveScript. The general-purpose core of the language has been embedded in Netscape, Internet Explorer, and other web browsers.\n\nThe ECMA-262 Specification defined a standard version of the core JavaScript language.\n\n- JavaScript is a lightweight, interpreted programming language.\n- Designed for creating network-centric applications.\n- Complementary to and integrated with Java.\n- Complementary to and integrated with HTML.\n- Open and cross-platform\n\nClient-side JavaScript\n\nClient-side JavaScript is the most common form of the language. The script should be included in or referenced by an HTML document for the code to be interpreted by the browser.\n\nIt means that a web page need not be a static HTML, but can include programs that interact with the user, control the browser, and dynamically create HTML content.\n\nThe JavaScript client-side mechanism provides many advantages over traditional CGI server-side scripts. For example, you might use JavaScript to check if the user has entered a valid e-mail address in a form field.\n\nThe JavaScript code is executed when the user submits the form, and only if all the entries are valid, they would be submitted to the Web Server.\n\nJavaScript can be used to trap user-initiated events such as button clicks, link navigation, and other actions that the user initiates explicitly or implicitly.\n\nAdvantages of JavaScript\n\nThe merits of using JavaScript are –\n\n- **Less server interaction** – You can validate user input before sending the page off to the server. This saves server traffic, which means less load on your server.\n\n- **Immediate feedback to the visitors** – They don't have to wait for a page reload to see if they have forgotten to enter something.\n\n- **Increased interactivity** – You can create interfaces that react when the user hovers over them with a mouse or activates them via the keyboard.\n\n- **Richer interfaces** – You can use JavaScript to include such items as drag-and-drop components and sliders to give a Rich Interface to your site visitors.\n\nLimitations of JavaScript\nWe cannot treat JavaScript as a full-fledged programming language. It lacks the following important features —\n\n- Client-side JavaScript does not allow the reading or writing of files. This has been kept for security reason.\n- JavaScript cannot be used for networking applications because there is no such support available.\n- JavaScript doesn’t have any multithreading or multiprocessor capabilities.\n\nOnce again, JavaScript is a lightweight, interpreted programming language that allows you to build interactivity into otherwise static HTML pages.\n\n**JavaScript Development Tools**\n\nOne of major strengths of JavaScript is that it does not require expensive development tools. You can start with a simple text editor such as Notepad. Since it is an interpreted language inside the context of a web browser, you don't even need to buy a compiler.\n\nTo make our life simpler, various vendors have come up with very nice JavaScript editing tools. Some of them are listed here —\n\n- **Microsoft FrontPage** – Microsoft has developed a popular HTML editor called FrontPage. FrontPage also provides web developers with a number of JavaScript tools to assist in the creation of interactive websites.\n- **Macromedia Dreamweaver MX** – Macromedia Dreamweaver MX is a very popular HTML and JavaScript editor in the professional web development crowd. It provides several handy prebuilt JavaScript components, integrates well with databases, and conforms to new standards such as XHTML and XML.\n- **Macromedia HomeSite 5** – HomeSite 5 is a well-liked HTML and JavaScript editor from Macromedia that can be used to manage personal websites effectively.\n\n**Where is JavaScript Today?**\n\nThe ECMAScript Edition 5 standard will be the first update to be released in over four years. JavaScript 2.0 conforms to Edition 5 of the ECMAScript standard, and the difference between the two is extremely minor.\n\nThe specification for JavaScript 2.0 can be found on the following site: [http://www.ecmascript.org/](http://www.ecmascript.org/)\n\nToday, Netscape's JavaScript and Microsoft's JScript conform to the ECMAScript standard, although both the languages still support the features that are not a part of the standard.\n\n**JavaScript - Syntax**\n\nJavaScript can be implemented using JavaScript statements that are placed within the `<script>...</script>` HTML tags in a web page.\n\nYou can place the `<script>` tags, containing your JavaScript, anywhere within you web page, but it is normally recommended that you should keep it within the `<head>` tags.\n\nThe `<script>` tag alerts the browser program to start interpreting all the text between these tags as a script. A simple syntax of your JavaScript will appear as follows.\n\n```html\n<script>\nJavaScript code\n</script>\n```\n\nThe script tag takes two important attributes —\n\n- **Language** – This attribute specifies what scripting language you are using. Typically, its value will be javascript. Although recent versions of HTML (and XHTML, its successor) have\nphased out the use of this attribute.\n\n- **Type** – This attribute is what is now recommended to indicate the scripting language in use and its value should be set to \"text/javascript\".\n\nSo your JavaScript segment will look like –\n\n```html\n<script language=\"javascript\" type=\"text/javascript\"><br>\n Javascript code<br>\n</script>\n```\n\n### Your First JavaScript Script\n\nLet us take a sample example to print out \"Hello World\". We added an optional HTML comment that surrounds our JavaScript code. This is to save our code from a browser that does not support JavaScript. The comment ends with a \"//-->\". Here \"//\" signifies a comment in JavaScript, so we add that to prevent a browser from reading the end of the HTML comment as a piece of JavaScript code. Next, we call a function `document.write` which writes a string into our HTML document.\n\nThis function can be used to write text, HTML, or both. Take a look at the following code.\n\n```html\n<html><br>\n <body><br>\n <script language=\"javascript\" type=\"text/javascript\"><br>\n <!--<br>\n document.write(\"Hello World!\")<br>\n //--><br>\n </script><br>\n </body><br>\n</html>\n```\n\nThis code will produce the following result –\n\nHello World!\n\n### Whitespace and Line Breaks\n\nJavaScript ignores spaces, tabs, and newlines that appear in JavaScript programs. You can use spaces, tabs, and newlines freely in your program and you are free to format and indent your programs in a neat and consistent way that makes the code easy to read and understand.\n\n### Semicolons are Optional\n\nSimple statements in JavaScript are generally followed by a semicolon character, just as they are in C, C++, and Java. JavaScript, however, allows you to omit this semicolon if each of your statements are placed on a separate line. For example, the following code could be written without semicolons.\n\n```html\n<script language=\"javascript\" type=\"text/javascript\"><br>\n <!--<br>\n var1 = 10<br>\n var2 = 20<br>\n //--><br>\n</script>\n```\n\nBut when formatted in a single line as follows, you must use semicolons –\n\n```html\n<script language=\"javascript\" type=\"text/javascript\"><br>\n <!--<br>\n var1 = 10; var2 = 20;<br>\n //--><br>\n</script>\n```\n\n**Note** – It is a good programming practice to use semicolons.\nCase Sensitivity\n\nJavaScript is a case-sensitive language. This means that the language keywords, variables, function names, and any other identifiers must always be typed with a consistent capitalization of letters.\n\nSo the identifiers Time and TIME will convey different meanings in JavaScript.\n\n**NOTE** – Care should be taken while writing variable and function names in JavaScript.\n\nComments in JavaScript\n\nJavaScript supports both C-style and C++-style comments, Thus –\n\n- Any text between a // and the end of a line is treated as a comment and is ignored by JavaScript.\n- Any text between the characters /* and */ is treated as a comment. This may span multiple lines.\n- JavaScript also recognizes the HTML comment opening sequence <!--. JavaScript treats this as a single-line comment, just as it does the // comment.\n- The HTML comment closing sequence --> is not recognized by JavaScript so it should be written as //-->\n\nExample\n\nThe following example shows how to use comments in JavaScript.\n\n```html\n<script language=\"javascript\" type=\"text/javascript\">\n<!--\n // This is a comment. It is similar to comments in C++\n /*\n * This is a multiline comment in JavaScript\n * It is very similar to comments in C Programming\n */\n <!-->\n</script>\n```\n\nENABLING JAVASCRIPT IN BROWSERS\n\nAll the modern browsers come with built-in support for JavaScript. Frequently, you may need to enable or disable this support manually. This chapter explains the procedure of enabling and disabling JavaScript support in your browsers: Internet Explorer, Firefox, chrome, and Opera.\n\nJavaScript in Internet Explorer\n\nHere are simple steps to turn on or turn off JavaScript in your Internet Explorer –\n\n- Follow **Tools → Internet Options** from the menu.\n- Select **Security** tab from the dialog box.\n- Click the **Custom Level** button.\n- Scroll down till you find **Scripting option**.\n- Select **Enable** radio button under **Active scripting**.\n- Finally click OK and come out\n\nTo disable JavaScript support in your Internet Explorer, you need to select **Disable** radio button\nunder Active scripting.\n\nJavaScript in Firefox\n\nHere are the steps to turn on or turn off JavaScript in Firefox –\n\n- Open a new tab → type about: config in the address bar.\n- Then you will find the warning dialog. Select I’ll be careful, I promise!\n- Then you will find the list of configure options in the browser.\n- In the search bar, type javascript.enabled.\n- There you will find the option to enable or disable javascript by right-clicking on the value of that option → select toggle.\n\nIf javascript.enabled is true; it converts to false upon clicking toggle. If javascript is disabled; it gets enabled upon clicking toggle.\n\nJavaScript in Chrome\n\nHere are the steps to turn on or turn off JavaScript in Chrome –\n\n- Click the Chrome menu at the top right hand corner of your browser.\n- Select Settings.\n- Click Show advanced settings at the end of the page.\n- Under the Privacy section, click the Content settings button.\n- In the \"Javascript\" section, select \"Do not allow any site to run JavaScript\" or \"Allow all sites to run JavaScript (recommended)\".\n\nJavaScript in Opera\n\nHere are the steps to turn on or turn off JavaScript in Opera –\n\n- Follow Tools → Preferences from the menu.\n- Select Advanced option from the dialog box.\n- Select Content from the listed items.\n- Select Enable JavaScript checkbox.\n- Finally click OK and come out.\n\nTo disable JavaScript support in your Opera, you should not select the Enable JavaScript checkbox.\n\nWarning for Non-JavaScript Browsers\n\nIf you have to do something important using JavaScript, then you can display a warning message to the user using <noscript> tags.\n\nYou can add a noscript block immediately after the script block as follows –\n\n```html\n<html>\n<body>\n <script language=\"javascript\" type=\"text/javascript\">\n <!--\n document.write(\"Hello World!\")\n //-->\n </script>\n</body>\n</html>\n```\nNow, if the user’s browser does not support JavaScript or JavaScript is not enabled, then the message from <noscript> will be displayed on the screen.\n\n**JAVASCRIPT - PLACEMENT IN HTML FILE**\n\nThere is a flexibility given to include JavaScript code anywhere in an HTML document. However the most preferred ways to include JavaScript in an HTML file are as follows –\n\n- Script in <head>...</head> section.\n- Script in <body>...</body> section.\n- Script in <body>...</body> and <head>...</head> sections.\n- Script in an external file and then include in <head>...</head> section.\n\nIn the following section, we will see how we can place JavaScript in an HTML file in different ways.\n\n**JavaScript in <head>...</head> section**\n\nIf you want to have a script run on some event, such as when a user clicks somewhere, then you will place that script in the head as follows –\n\n```html\n<html>\n <head>\n <script type=\"text/javascript\">\n <!--\n function sayHello() {\n alert(\"Hello World\")\n }\n //-->\n </script>\n </head>\n <body>\n <input type=\"button\" onclick=\"sayHello()\" value=\"Say Hello\" />\n </body>\n</html>\n```\n\nThis code will produce the following results –\n\n**JavaScript in <body>...</body> section**\n\nIf you need a script to run as the page loads so that the script generates content in the page, then\nthe script goes in the <body> portion of the document. In this case, you would not have any function defined using JavaScript. Take a look at the following code.\n\n```html\n<html>\n <head>\n </head>\n <body>\n <script type=\"text/javascript\">\n <!--\n document.write(\"Hello World\")\n //-->\n </script>\n <p>This is web page body</p>\n </body>\n</html>\n```\n\nThis code will produce the following results –\n\n**JavaScript in <body> and <head> Sections**\n\nYou can put your JavaScript code in <head> and <body> section altogether as follows –\n\n```html\n<html>\n <head>\n <script type=\"text/javascript\">\n <!--\n function sayHello()\n {\n alert(\"Hello World\")\n }\n //-->\n </script>\n </head>\n <body>\n <script type=\"text/javascript\">\n <!--\n document.write(\"Hello World\")\n //-->\n </script>\n <input type=\"button\" onclick=\"sayHello()\" value=\"Say Hello\" />\n </body>\n</html>\n```\n\nThis code will produce the following result –\nJavaScript in External File\n\nAs you begin to work more extensively with JavaScript, you will be likely to find that there are cases where you are reusing identical JavaScript code on multiple pages of a site.\n\nYou are not restricted to be maintaining identical code in multiple HTML files. The script tag provides a mechanism to allow you to store JavaScript in an external file and then include it into your HTML files.\n\nHere is an example to show how you can include an external JavaScript file in your HTML code using script tag and its src attribute.\n\n```html\n<html>\n <head>\n <script type=\"text/javascript\" src=\"filename.js\"></script>\n </head>\n <body> ......\n </body>\n</html>\n```\n\nTo use JavaScript from an external file source, you need to write all your JavaScript source code in a simple text file with the extension \".js\" and then include that file as shown above.\n\nFor example, you can keep the following content in filename.js file and then you can use sayHello function in your HTML file after including the filename.js file.\n\n```javascript\nfunction sayHello() {\n alert(\"Hello World\")\n}\n```\n\nJAVASCRIPT - VARIABLES\n\nJavaScript Datatypes\n\nOne of the most fundamental characteristics of a programming language is the set of data types it supports. These are the type of values that can be represented and manipulated in a programming language.\n\nJavaScript allows you to work with three primitive data types –\n\n- **Numbers**, eg. 123, 120.50 etc.\n- **Strings** of text e.g. \"This text string\" etc.\n- **Boolean** e.g. true or false.\n\nJavaScript also defines two trivial data types, **null** and **undefined**, each of which defines only a single value. In addition to these primitive data types, JavaScript supports a composite data type known as object. We will cover objects in detail in a separate chapter.\n\n**Note** – Java does not make a distinction between integer values and floating-point values. All numbers in JavaScript are represented as floating-point values. JavaScript represents numbers\nusing the 64-bit floating-point format defined by the IEEE 754 standard.\n\n**JavaScript Variables**\n\nLike many other programming languages, JavaScript has variables. Variables can be thought of as named containers. You can place data into these containers and then refer to the data simply by naming the container.\n\nBefore you use a variable in a JavaScript program, you must declare it. Variables are declared with the `var` keyword as follows.\n\n```html\n<script type=\"text/javascript\">\n<!--\n var money;\n var name;\n //-->\n</script>\n```\n\nYou can also declare multiple variables with the same `var` keyword as follows −\n\n```html\n<script type=\"text/javascript\">\n<!--\n var money, name;\n //-->\n</script>\n```\n\nStoring a value in a variable is called **variable initialization**. You can do variable initialization at the time of variable creation or at a later point in time when you need that variable.\n\nFor instance, you might create a variable named `money` and assign the value 2000.50 to it later. For another variable, you can assign a value at the time of initialization as follows.\n\n```html\n<script type=\"text/javascript\">\n<!--\n var name = \"Ali\";\n var money;\n money = 2000.50;\n //-->\n</script>\n```\n\n**Note** – Use the `var` keyword only for declaration or initialization, once for the life of any variable name in a document. You should not re-declare same variable twice.\n\nJavaScript is **untyped** language. This means that a JavaScript variable can hold a value of any data type. Unlike many other languages, you don’t have to tell JavaScript during variable declaration what type of value the variable will hold. The value type of a variable can change during the execution of a program and JavaScript takes care of it automatically.\n\n**JavaScript Variable Scope**\n\nThe scope of a variable is the region of your program in which it is defined. JavaScript variables have only two scopes.\n\n- **Global Variables** – A global variable has global scope which means it can be defined anywhere in your JavaScript code.\n\n- **Local Variables** – A local variable will be visible only within a function where it is defined. Function parameters are always local to that function.\n\nWithin the body of a function, a local variable takes precedence over a global variable with the same name. If you declare a local variable or function parameter with the same name as a global variable, you effectively hide the global variable. Take a look into the following example.\n\n```html\n<script type=\"text/javascript\">\n<!--\n</script>\n```\n```javascript\nvar myVar = \"global\"; // Declare a global variable\nfunction checkscope() {\n var myVar = \"local\"; // Declare a local variable\ndocument.write(myVar);\n}\n\n//-->\n</script>\n\nThis produces the following result –\n\n```\nlocal\n```\n\n### JavaScript Variable Names\n\nWhile naming your variables in JavaScript, keep the following rules in mind.\n\n- You should not use any of the JavaScript reserved keywords as a variable name. These keywords are mentioned in the next section. For example, `break` or `boolean` variable names are not valid.\n\n- JavaScript variable names should not start with a numeral (0-9). They must begin with a letter or an underscore character. For example, `123test` is an invalid variable name but `_123test` is a valid one.\n\n- JavaScript variable names are case-sensitive. For example, `Name` and `name` are two different variables.\n\n### JavaScript Reserved Words\n\nA list of all the reserved words in JavaScript are given in the following table. They cannot be used as JavaScript variables, functions, methods, loop labels, or any object names.\n\n<table>\n<thead>\n<tr>\n<th>abstract</th>\n<th>else</th>\n<th>instanceof</th>\n<th>switch</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>boolean</td>\n<td>enum</td>\n<td>int</td>\n<td>synchronized</td>\n</tr>\n<tr>\n<td>break</td>\n<td>export</td>\n<td>interface</td>\n<td>this</td>\n</tr>\n<tr>\n<td>byte</td>\n<td>extends</td>\n<td>long</td>\n<td>throw</td>\n</tr>\n<tr>\n<td>case</td>\n<td>false</td>\n<td>native</td>\n<td>throws</td>\n</tr>\n<tr>\n<td>catch</td>\n<td>final</td>\n<td>new</td>\n<td>transient</td>\n</tr>\n<tr>\n<td>char</td>\n<td>finally</td>\n<td>null</td>\n<td>true</td>\n</tr>\n<tr>\n<td>class</td>\n<td>float</td>\n<td>package</td>\n<td>try</td>\n</tr>\n<tr>\n<td>const</td>\n<td>for</td>\n<td>private</td>\n<td>typeof</td>\n</tr>\n<tr>\n<td>continue</td>\n<td>function</td>\n<td>protected</td>\n<td>var</td>\n</tr>\n<tr>\n<td>debugger</td>\n<td>goto</td>\n<td>public</td>\n<td>void</td>\n</tr>\n<tr>\n<td>default</td>\n<td>if</td>\n<td>return</td>\n<td>volatile</td>\n</tr>\n<tr>\n<td>delete</td>\n<td>implements</td>\n<td>short</td>\n<td>while</td>\n</tr>\n<tr>\n<td>do</td>\n<td>import</td>\n<td>static</td>\n<td>with</td>\n</tr>\n<tr>\n<td>double</td>\n<td>in</td>\n<td>super</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n```\n**What is an operator?**\n\nLet us take a simple expression $4 + 5$ is equal to $9$. Here $4$ and $5$ are called **operands** and `$+$` is called the **operator**. JavaScript supports the following types of operators.\n\n- Arithmetic Operators\n- Comparision Operators\n- Logical (or Relational) Operators\n- Assignment Operators\n- Conditional (or ternary) Operators\n\nLet's have a look on all operators one by one.\n\n**Arithmetic Operators**\n\nJavaScript supports the following arithmetic operators −\n\nAssume variable $A$ holds $10$ and variable $B$ holds $20$, then −\n\n<table>\n<thead>\n<tr>\n<th>Sr.No</th>\n<th>Operator and Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>$+$ (Addition)</td>\n</tr>\n<tr>\n<td></td>\n<td>Adds two operands</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> $A + B$ will give $30$</td>\n</tr>\n<tr>\n<td>2</td>\n<td>$-$ (Subtraction)</td>\n</tr>\n<tr>\n<td></td>\n<td>Subtracts the second operand from the first</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> $A - B$ will give $-10$</td>\n</tr>\n<tr>\n<td>3</td>\n<td>$*$ (Multiplication)</td>\n</tr>\n<tr>\n<td></td>\n<td>Multiply both operands</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> $A * B$ will give $200$</td>\n</tr>\n<tr>\n<td>4</td>\n<td>$/$ (Division)</td>\n</tr>\n<tr>\n<td></td>\n<td>Divide the numerator by the denominator</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> $B / A$ will give $2$</td>\n</tr>\n<tr>\n<td>5</td>\n<td>$%$ (Modulus)</td>\n</tr>\n<tr>\n<td></td>\n<td>Outputs the remainder of an integer division</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> $B % A$ will give $0$</td>\n</tr>\n</tbody>\n</table>\n++ (Increment)\n\nIncreases an integer value by one\n\n**Ex:** A++ will give 11\n\n-- (Decrement)\n\nDecreases an integer value by one\n\n**Ex:** A-- will give 9\n\n**Note** – Addition operator (+) works for Numeric as well as Strings. e.g. \"a\" + 10 will give \"a10\".\n\n**Example**\n\nThe following code shows how to use arithmetic operators in JavaScript.\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n<!--\nvar a = 33;\nvar b = 10;\nvar c = \"Test\";\nvar linebreak = \"<br />\n\ndocument.write(\"a + b = \");\nresult = a + b;\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"a - b = \");\nresult = a - b;\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"a / b = \");\nresult = a / b;\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"a % b = \");\nresult = a % b;\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"a + b + c = \");\nresult = a + b + c;\ndocument.write(result);\ndocument.write(linebreak);\n\na = a++;\ndocument.write(\"a++ = \");\nresult = a++;\ndocument.write(result);\ndocument.write(linebreak);\n\nb = b--;\ndocument.write(\"b-- = \");\nresult = b--;\ndocument.write(result);\n\n //-- -->\n</script>\n</body>\n</html>\n```\nOutput\n\n```\na + b = 43\na - b = 23\na / b = 3.3\na % b = 3\na + b + c = 43\na++ = 33\nb-- = 10\n```\n\nSet the variables to different values and then try...\n\nComparison Operators\n\nJavaScript supports the following comparison operators –\n\nAssume variable A holds 10 and variable B holds 20, then –\n\n<table>\n<thead>\n<tr>\n<th>Sr.No</th>\n<th>Operator and Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>= (Equal)</td>\n</tr>\n<tr>\n<td></td>\n<td>Checks if the value of two operands are equal or not, if yes, then the condition becomes true.</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: (A == B) is not true.</td>\n</tr>\n<tr>\n<td>2</td>\n<td>!= (Not Equal)</td>\n</tr>\n<tr>\n<td></td>\n<td>Checks if the value of two operands are equal or not, if the values are not equal, then the condition becomes true.</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: (A != B) is true.</td>\n</tr>\n<tr>\n<td>3</td>\n<td>> (Greater than)</td>\n</tr>\n<tr>\n<td></td>\n<td>Checks if the value of the left operand is greater than the value of the right operand, if yes, then the condition becomes true.</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: (A > B) is not true.</td>\n</tr>\n<tr>\n<td>4</td>\n<td>< (Less than)</td>\n</tr>\n<tr>\n<td></td>\n<td>Checks if the value of the left operand is less than the value of the right operand, if yes, then the condition becomes true.</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: (A < B) is true.</td>\n</tr>\n<tr>\n<td>5</td>\n<td>>= (Greater than or Equal to)</td>\n</tr>\n</tbody>\n</table>\nChecks if the value of the left operand is greater than or equal to the value of the right operand, if yes, then the condition becomes true.\n\n**Ex:** \\((A \\geq B)\\) is not true.\n\n6\n\n\\(\\leq\\) (Less than or Equal to)\n\nChecks if the value of the left operand is less than or equal to the value of the right operand, if yes, then the condition becomes true.\n\n**Ex:** \\((A \\leq B)\\) is true.\n\n**Example**\n\nThe following code shows how to use comparison operators in JavaScript.\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n <!---\n var a = 10;\n var b = 20;\n var linebreak = \"<br />\";\n\n document.write(\"(a == b) => \");\n result = (a == b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"(a < b) => \");\n result = (a < b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"(a > b) => \");\n result = (a > b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"(a != b) => \");\n result = (a != b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"(a >= b) => \");\n result = (a >= b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"(a <= b) => \");\n result = (a <= b);\n document.write(result);\n document.write(linebreak);\n //-->;\n </script>\n\nSet the variables to different values and different operators and then try...\n\n</body>\n</html>\n\n**Output**\nLogical Operators\n\nJavaScript supports the following logical operators –\n\nAssume variable A holds 10 and variable B holds 20, then –\n\n<table>\n<thead>\n<tr>\n<th>Sr.No</th>\n<th>Operator and Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>&& (Logical AND)</td>\n</tr>\n<tr>\n<td></td>\n<td>If both the operands are non-zero, then the condition becomes true.</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> (A && B) is true.</td>\n</tr>\n<tr>\n<td>2</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>If any of the two operands are non-zero, then the condition becomes true.</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> (A</td>\n</tr>\n<tr>\n<td>3</td>\n<td>! (Logical NOT)</td>\n</tr>\n<tr>\n<td></td>\n<td>Reverses the logical state of its operand. If a condition is true, then the Logical NOT operator will make it false.</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> ! (A && B) is false.</td>\n</tr>\n</tbody>\n</table>\n\nExample\n\nTry the following code to learn how to implement Logical Operators in JavaScript.\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n\n//--\nvar a = true;\nvar b = false;\nvar linebreak = \"<br />\";\n\ndocument.write(\"(a && b) => \");\nresult = (a && b);\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"(a || b) => \");\nresult = (a || b);\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"!(a && b) => \");\nresult = (!(a && b));\n\n</script>\n</body>\n</html>\n```\nOutput\n\n(a && b) => false\n(a || b) => true\n!(a && b) => true\nSet the variables to different values and different operators and then try...\n\nBitwise Operators\n\nJavaScript supports the following bitwise operators –\n\nAssume variable A holds 2 and variable B holds 3, then –\n\n<table>\n<thead>\n<tr>\n<th>Sr.No</th>\n<th>Operator and Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>& (Bitwise AND)</td>\n</tr>\n<tr>\n<td></td>\n<td>It performs a Boolean AND operation on each bit of its integer arguments.</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> (A & B) is 2.</td>\n</tr>\n<tr>\n<td>2</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>It performs a Boolean OR operation on each bit of its integer arguments.</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> (A</td>\n</tr>\n<tr>\n<td>3</td>\n<td>^ (Bitwise XOR)</td>\n</tr>\n<tr>\n<td></td>\n<td>It performs a Boolean exclusive OR operation on each bit of its integer arguments.</td>\n</tr>\n<tr>\n<td></td>\n<td>Exclusive OR means that either operand one is true or operand two is true, but not both.</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> (A ^ B) is 1.</td>\n</tr>\n<tr>\n<td>4</td>\n<td>~ (Bitwise Not)</td>\n</tr>\n<tr>\n<td></td>\n<td>It is a unary operator and operates by reversing all the bits in the operand.</td>\n</tr>\n<tr>\n<td></td>\n<td><strong>Ex:</strong> (~B) is -4.</td>\n</tr>\n<tr>\n<td>5</td>\n<td><< (Left Shift)</td>\n</tr>\n<tr>\n<td></td>\n<td>It moves all the bits in its first operand to the left by the number of places specified in the second operand. New bits are filled with zeros. Shifting a value left by one position is equivalent to multiplying it by 2, shifting two positions is equivalent to multiplying by 4, and so on.</td>\n</tr>\n</tbody>\n</table>\nEx: \\((A \\ll 1)\\) is 4.\n\n6\n\n**>> (Right Shift)**\n\nBinary Right Shift Operator. The left operand’s value is moved right by the number of bits specified by the right operand.\n\nEx: \\((A >> 1)\\) is 1.\n\n7\n\n**>>> (Right shift with Zero)**\n\nThis operator is just like the >> operator, except that the bits shifted in on the left are always zero.\n\nEx: \\((A >>> 1)\\) is 1.\n\nExample\n\nTry the following code to implement Bitwise operator in JavaScript.\n\n```html\n<body>\n<script type=\"text/javascript\">\n<!--\nvar a = 2; // Bit presentation 10\nvar b = 3; // Bit presentation 11\nvar linebreak = \"<br />\n\ndocument.write(\"(a & b) => \");\nresult = (a & b);\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"(a | b) => \");\nresult = (a | b);\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"(a ^ b) => \");\nresult = (a ^ b);\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"(~b) => \");\nresult = (~b);\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"(a << b) => \");\nresult = (a << b);\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"(a >> b) => \");\nresult = (a >> b);\ndocument.write(result);\ndocument.write(linebreak);\n//-->\n</script>\n<p>Set the variables to different values and different operators and then</p>\n```\ntry...\n</body>\n</html>\n\n(a & b) => 2\n(a | b) => 3\n(a ^ b) => 1\n(~b) => -4\n(a << b) => 16\n(a >> b) => 0\nSet the variables to different values and different operators and then try...\n\n**Assignment Operators**\n\nJavaScript supports the following assignment operators –\n\n<table>\n<thead>\n<tr>\n<th>Sr.No</th>\n<th>Operator and Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>= (Simple Assignment )</td>\n</tr>\n<tr>\n<td></td>\n<td>Assigns values from the right side operand to the left side operand</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: C = A + B will assign the value of A + B into C</td>\n</tr>\n<tr>\n<td>2</td>\n<td>+= (Add and Assignment)</td>\n</tr>\n<tr>\n<td></td>\n<td>It adds the right operand to the left operand and assigns the result to the left operand.</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: C += A is equivalent to C = C + A</td>\n</tr>\n<tr>\n<td>3</td>\n<td>−= (Subtract and Assignment)</td>\n</tr>\n<tr>\n<td></td>\n<td>It subtracts the right operand from the left operand and assigns the result to the left operand.</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: C -= A is equivalent to C = C - A</td>\n</tr>\n<tr>\n<td>4</td>\n<td>*= (Multiply and Assignment)</td>\n</tr>\n<tr>\n<td></td>\n<td>It multiplies the right operand with the left operand and assigns the result to the left operand.</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: C *= A is equivalent to C = C * A</td>\n</tr>\n<tr>\n<td>5</td>\n<td>/= (Divide and Assignment)</td>\n</tr>\n<tr>\n<td></td>\n<td>It divides the left operand with the right operand and assigns the result to the left operand.</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: C /= A is equivalent to C = C / A</td>\n</tr>\n<tr>\n<td>6</td>\n<td>%= (Modules and Assignment)</td>\n</tr>\n<tr>\n<td></td>\n<td>It takes modulus using two operands and assigns the result to the left operand.</td>\n</tr>\n<tr>\n<td></td>\n<td>Ex: C %= A is equivalent to C = C % A</td>\n</tr>\n</tbody>\n</table>\n**Note** – Same logic applies to Bitwise operators so they will become like <<=, >>=, >>=, &=, |= and ^=.\n\n**Example**\n\nTry the following code to implement assignment operator in JavaScript.\n\n```html\n<html>\n<body>\n<script type=\"text/javascript\">\n<!--\n var a = 33;\n var b = 10;\n var linebreak = \"<br />\n\n document.write(\"Value of a => (a = b) => \");\n result = (a = b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"Value of a => (a += b) => \");\n result = (a += b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"Value of a => (a -= b) => \");\n result = (a -= b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"Value of a => (a *= b) => \");\n result = (a *= b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"Value of a => (a /= b) => \");\n result = (a /= b);\n document.write(result);\n document.write(linebreak);\n\n document.write(\"Value of a => (a %= b) => \");\n result = (a %= b);\n document.write(result);\n document.write(linebreak);\n\n //-->\n</script>\n<p>Set the variables to different values and different operators and then try...</p>\n</body>\n</html>\n```\n\n**Output**\n\nValue of a => (a = b) => 10 \nValue of a => (a += b) => 20 \nValue of a => (a -= b) => 10 \nValue of a => (a *= b) => 100 \nValue of a => (a /= b) => 10 \nValue of a => (a %= b) => 0 \nSet the variables to different values and different operators and then try...\n\n**Miscellaneous Operator**\nWe will discuss two operators here that are quite useful in JavaScript: the **conditional operator** (?) and the **typeof operator**.\n\n### Conditional Operator (?:)\n\nThe conditional operator first evaluates an expression for a true or false value and then executes one of the two given statements depending upon the result of the evaluation.\n\n<table>\n<thead>\n<tr>\n<th>Sr.No</th>\n<th>Operator and Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>? : (Conditional )</td>\n</tr>\n<tr>\n<td></td>\n<td>If Condition is true? Then value X : Otherwise value Y</td>\n</tr>\n</tbody>\n</table>\n\n**Example**\n\nTry the following code to understand how the Conditional Operator works in JavaScript.\n\n```html\n<html>\n<body>\n<script type=\"text/javascript\">\n<!--\nvar a = 10;\nvar b = 20;\nvar linebreak = \"<br />\";\n\ndocument.write(\"((a > b) ? 100 : 200) => \");\nresult = (a > b) ? 100 : 200;\ndocument.write(result);\ndocument.write(linebreak);\n\ndocument.write(\"((a < b) ? 100 : 200) => \");\nresult = (a < b) ? 100 : 200;\ndocument.write(result);\ndocument.write(linebreak);\n//-->\n</script>\n<p>Set the variables to different values and different operators and then try...</p>\n</body>\n</html>\n```\n\n**Output**\n\n```\n((a > b) ? 100 : 200) => 200\n((a < b) ? 100 : 200) => 100\n```\n\nSet the variables to different values and different operators and then try...\n\n### typeof Operator\n\nThe **typeof** operator is a unary operator that is placed before its single operand, which can be of any type. Its value is a string indicating the data type of the operand.\n\nThe **typeof** operator evaluates to \"number\", \"string\", or \"boolean\" if its operand is a number, string, or boolean value and returns true or false based on the evaluation.\n\nHere is a list of the return values for the **typeof** Operator.\nType | String Returned by typeof\n--- | ---\nNumber | \"number\"\nString | \"string\"\nBoolean | \"boolean\"\nObject | \"object\"\nFunction | \"function\"\nUndefined | \"undefined\"\nNull | \"object\"\n\n**Example**\n\nThe following code shows how to implement `typeof` operator.\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n<!--\nvar a = 10;\nvar b = \"String\";\nvar linebreak = \"<br />\n\nresult = (typeof b == \"string\" ? \"B is String\" : \"B is Numeric\");\ndocument.write(\"Result => \");\ndocument.write(result);\ndocument.write(linebreak);\n\nresult = (typeof a == \"string\" ? \"A is String\" : \"A is Numeric\");\ndocument.write(\"Result => \");\ndocument.write(result);\ndocument.write(linebreak);\n//-->\n\n</script>\n\n<p>Set the variables to different values and different operators and then try... </p>\n</body>\n</html>\n```\n\n**Output**\n\nResult => B is String\nResult => A is Numeric\nSet the variables to different values and different operators and then try...\n\nJAVASCRIPT - IF...ELSE STATEMENT\n\nWhile writing a program, there may be a situation when you need to adopt one out of a given set of paths. In such cases, you need to use conditional statements that allow your program to make correct decisions and perform right actions.\n\nJavaScript supports conditional statements which are used to perform different actions based on different conditions. Here we will explain the **if..else** statement.\n\n**Flow Chart of if-else**\n\nThe following flow chart shows how the if-else statement works.\nJavaScript supports the following forms of if..else statement –\n\n- if statement\n- if...else statement\n- if...else if... statement.\n\n### if statement\n\nThe **if** statement is the fundamental control statement that allows JavaScript to make decisions and execute statements conditionally.\n\n### Syntax\n\nThe syntax for a basic if statement is as follows –\n\n```javascript\nif (expression){\n Statement(s) to be executed if expression is true\n}\n```\n\nHere a JavaScript expression is evaluated. If the resulting value is true, the given statement(s) are executed. If the expression is false, then no statement would be not executed. Most of the times, you will use comparison operators while making decisions.\n\n### Example\n\nTry the following example to understand how the if statement works.\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n<!--\nvar age = 20;\n\nif( age > 18 ){\n document.write(\"<b>Qualifies for driving</b>\");\n}\n//-->\n</script>\n\n<p>Set the variable to different value and then try...</p>\n</body>\n</html>\n```\nIf...else statement:\n\nThe ‘if...else’ statement is the next form of control statement that allows JavaScript to execute statements in a more controlled way.\n\nSyntax\n\n```javascript\nif (expression){\n Statement(s) to be executed if expression is true\n}\nelse{\n Statement(s) to be executed if expression is false\n}\n```\n\nHere JavaScript expression is evaluated. If the resulting value is true, the given statement(s) in the ‘if’ block, are executed. If the expression is false, then the given statement(s) in the else block are executed.\n\nExample\n\nTry the following code to learn how to implement an if-else statement in JavaScript.\n\n```html\n<html>\n<body>\n <script type=\"text/javascript\">\n <!--\n var age = 15;\n if( age > 18 ){\n document.write(\"<b>Qualifies for driving</b>\\n\";\n }\n else{\n document.write(\"<b>Does not qualify for driving</b>\\n\";\n }\n //-->\n </script>\n <p>Set the variable to different value and then try...</p>\n</body>\n</html>\n```\n\nOutput\n\nDoes not qualify for driving\nSet the variable to different value and then try...\n\nIf...else if... statement\n\nThe if...else if... statement is an advanced form of if...else that allows JavaScript to make a correct decision out of several conditions.\n\nSyntax\nThe syntax of an if-else-if statement is as follows –\n\n```javascript\nif (expression 1){\n Statement(s) to be executed if expression 1 is true\n}\nelse if (expression 2){\n Statement(s) to be executed if expression 2 is true\n}\nelse if (expression 3){\n Statement(s) to be executed if expression 3 is true\n}\nelse{\n Statement(s) to be executed if no expression is true\n}\n```\n\nThere is nothing special about this code. It is just a series of if statements, where each if is a part of the else clause of the previous statement. Statement(s) are executed based on the true condition, if none of the conditions is true, then the else block is executed.\n\n**Example**\n\nTry the following code to learn how to implement an if-else-if statement in JavaScript.\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n<!---\n var book = \"maths\";\n if (book == \"history\"){\n document.write(\"<b>History Book</b>\");\n }\n else if (book == \"maths\"){\n document.write(\"<b>Maths Book</b>\");\n }\n else if (book == \"economics\"){\n document.write(\"<b>Economics Book</b>\");\n }\n else{\n document.write(\"<b>Unknown Book</b>\");\n }\n//-->\n</script>\n\n<p>Set the variable to different value and then try...</p>\n</body>\n</html>\n```\n\n**Output**\n\nMaths Book\nSet the variable to different value and then try...\n\n**JAVASCRIPT - SWITCH CASE**\n\nYou can use multiple if...else...if statements, as in the previous chapter, to perform a multiway branch. However, this is not always the best solution, especially when all of the branches depend on the value of a single variable.\n\nStarting with JavaScript 1.2, you can use a switch statement which handles exactly this situation,\nand it does so more efficiently than repeated if...else if statements.\n\n**Flow Chart**\n\nThe following flow chart explains a switch-case statement works.\n\n```plaintext\nswitch (expression)\n{\n case condition 1: statement(s) \n break;\n case condition 2: statement(s) \n break;\n ... \n case condition n: statement(s) \n break;\n default: statement(s)\n}\n```\n\nThe **break** statements indicate the end of a particular case. If they were omitted, the interpreter would continue executing each statement in each of the following cases.\nWe will explain \\texttt{break} statement in \\textit{Loop Control} chapter.\n\n\\textbf{Example} \n\nTry the following example to implement switch-case statement.\n\n\\begin{verbatim}\n<html>\n<body>\n<script type=\"text/javascript\">\n <!--\n var grade='A';\n document.write(\"Entering switch block<br />\");\n switch (grade)\n {\n case 'A': document.write(\"Good job<br />\");\n break;\n case 'B': document.write(\"Pretty good<br />\");\n break;\n case 'C': document.write(\"Passed<br />\");\n break;\n case 'D': document.write(\"Not so good<br />\");\n break;\n case 'F': document.write(\"Failed<br />\");\n break;\n default: document.write(\"Unknown grade<br />\");\n }\n document.write(\"Exiting switch block\");\n //--> \n</script>\n<p>Set the variable to different value and then try...</p>\n</body>\n</html>\n\\end{verbatim}\n\n\\textbf{Output} \n\nEntering switch block \nGood job \nExiting switch block \nSet the variable to different value and then try...\n\nBreak statements play a major role in switch-case statements. Try the following code that uses switch-case statement without any break statement.\n\n\\begin{verbatim}\n<html>\n<body>\n<script type=\"text/javascript\">\n <!--\n var grade='A';\n document.write(\"Entering switch block<br />\");\n switch (grade)\n {\n case 'A': document.write(\"Good job<br />\");\n case 'B': document.write(\"Pretty good<br />\");\n case 'C': document.write(\"Passed<br />\");\n case 'D': document.write(\"Not so good<br />\");\n case 'F': document.write(\"Failed<br />\");\n default: document.write(\"Unknown grade<br />\");\n }\n</script>\n\\end{verbatim}\nOutput\n\nEntering switch block\nGood job\nPretty good\nPassed\nNot so good\nFailed\nUnknown grade\nExiting switch block\nSet the variable to different value and then try...\n\n**JAVASCRIPT - WHILE LOOPS**\n\nWhile writing a program, you may encounter a situation where you need to perform an action over and over again. In such situations, you would need to write loop statements to reduce the number of lines.\n\nJavaScript supports all the necessary loops to ease down the pressure of programming.\n\n**The while Loop**\n\nThe most basic loop in JavaScript is the **while** loop which would be discussed in this chapter. The purpose of a **while** loop is to execute a statement or code block repeatedly as long as an expression is true. Once the expression becomes **false**, the loop terminates.\n\n**Flow Chart**\n\nThe flow chart of **while loop** looks as follows –\nSyntax\n\nThe syntax of **while loop** in JavaScript is as follows –\n\n```\nwhile (expression)\n{\n Statement(s) to be executed if expression is true\n}\n```\n\nExample\n\nTry the following example to implement while loop.\n\n```\n<html>\n<body>\n\n<script type=\"text/javascript\">\n <!---\n var count = 0;\n document.write(\"Starting Loop \");\n\n while (count < 10){\n document.write(\"Current Count : \" + count + \"<br />\");\n count++;\n }\n document.write(\"Loop stopped!\");\n //-->\n\n <p>Set the variable to different value and then try...</p>\n\n</script>\n</body>\n</html>\n```\n\nOutput\n\nStarting Loop\nCurrent Count : 0\nCurrent Count : 1\nCurrent Count : 2\nCurrent Count : 3\nCurrent Count : 4\nCurrent Count : 5\nCurrent Count : 6\nCurrent Count : 7\nCurrent Count : 8\nCurrent Count : 9\nLoop stopped!\nSet the variable to different value and then try...\n\nThe do...while Loop\n\nThe **do...while** loop is similar to the **while** loop except that the condition check happens at the end of the loop. This means that the loop will always be executed at least once, even if the condition is **false**.\n\nFlow Chart\n\nThe flow chart of a **do-while** loop would be as follows –\n\n```\ndo{\n conditional code ;\n} while (condition)\n```\nSyntax\n\nThe syntax for **do-while** loop in JavaScript is as follows –\n\n```javascript\ndo{\n Statement(s) to be executed;\n} while (expression);\n```\n\n**Note** – Don’t miss the semicolon used at the end of the do...while loop.\n\nExample\n\nTry the following example to learn how to implement a **do-while** loop in JavaScript.\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n<!--\nvar count = 0;\n\ndocument.write(\"Starting Loop\" + \"<br />\");\ndo{\n document.write(\"Current Count : \" + count + \"<br />\");\n count++;\n}\nwhile (count < 5);\ndocument.write (\"Loop stopped!\");\n//-->\n</script>\n\n<p>Set the variable to different value and then try...</p>\n</body>\n</html>\n```\n\nOutput\n\nStarting Loop\nCurrent Count : 0\nCurrent Count : 1\nCurrent Count : 2\nCurrent Count : 3\nCurrent Count : 4\nLoop Stopped!\nSet the variable to different value and then try...\nThe ‘for’ loop is the most compact form of looping. It includes the following three important parts –\n\n- The **loop initialization** where we initialize our counter to a starting value. The initialization statement is executed before the loop begins.\n- The **test statement** which will test if a given condition is true or not. If the condition is true, then the code given inside the loop will be executed, otherwise the control will come out of the loop.\n- The **iteration statement** where you can increase or decrease your counter.\n\nYou can put all the three parts in a single line separated by semicolons.\n\n**Flow Chart**\n\nThe flow chart of a for loop in JavaScript would be as follows –\n\n![Flow Chart Image]\n\n**Syntax**\n\nThe syntax of for loop is JavaScript is as follows –\n\n```javascript\nfor (initialization; test condition; iteration statement){\n Statement(s) to be executed if test condition is true\n}\n```\n\n**Example**\n\nTry the following example to learn how a for loop works in JavaScript.\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n</script>\n\n```\nOutput\n\nStarting Loop\nCurrent Count : 0\nCurrent Count : 1\nCurrent Count : 2\nCurrent Count : 3\nCurrent Count : 4\nCurrent Count : 5\nCurrent Count : 6\nCurrent Count : 7\nCurrent Count : 8\nCurrent Count : 9\nLoop stopped!\nSet the variable to different value and then try...\n\nJAVA SCRIPT FOR...IN LOOP\n\nThe for...in loop is used to loop through an object's properties. As we have not discussed Objects yet, you may not feel comfortable with this loop. But once you understand how objects behave in JavaScript, you will find this loop very useful.\n\nSyntax\n\n```\nfor (var variablename in object){\n statement or block to execute\n}\n```\n\nIn each iteration, one property from object is assigned to variablename and this loop continues till all the properties of the object are exhausted.\n\nExample\n\nTry the following example to implement ‘for-in’ loop. It prints the web browser’s Navigator object.\n\n```\n<html>\n<body>\n\n <script type=\"text/javascript\">\n var aProperty;\n document.write(\"Navigator Object Properties<br /> \");\n\n for (aProperty in navigator) {\n document.write(aProperty);\n document.write(\"<br />\");\n }\n document.write (\"Exiting from the loop!\");\n //-->\n </script>\n\n<p>Set the variable to different object and then try...</p>\n</body>\n</html>\n```\n\nOutput\n\nNavigator Object Properties\nserviceWorker\nJavaScript - Loop Control\n\nJavaScript provides full control to handle loops and switch statements. There may be a situation when you need to come out of a loop without reaching at its bottom. There may also be a situation when you want to skip a part of your code block and start the next iteration of the loop.\n\nTo handle all such situations, JavaScript provides `break` and `continue` statements. These statements are used to immediately come out of any loop or to start the next iteration of any loop respectively.\n\n**The break Statement**\n\nThe `break` statement, which was briefly introduced with the `switch` statement, is used to exit a loop early, breaking out of the enclosing curly braces.\n\n**Flow Chart**\n\nThe flow chart of a break statement would look as follows –\n\n```\nCondition\n true\n Conditional Code\n Break statement\n false\n```\nExample\n\nThe following example illustrates the use of a break statement with a while loop. Notice how the loop breaks out early once $x$ reaches 5 and reaches to document.write (..) statement just below to the closing curly brace −\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n<!--\nvar x = 1;\ndocument.write(\"Entering the loop<br /> \");\n\nwhile (x < 20)\n{\n if (x == 5){\n break; // breaks out of loop completely\n }\n x = x + 1;\n document.write( x + \"<br />\");\n}\n\ndocument.write(\"Exiting the loop!<br /> \");\n//-->\n</script>\n<p>Set the variable to different value and then try...</p>\n</body>\n</html>\n```\n\nOutput\n\nEntering the loop\n2\n3\n4\n5\nExiting the loop!\nSet the variable to different value and then try...\n\nWe already have seen the usage of break statement inside a switch statement.\n\nThe continue Statement\n\nThe continue statement tells the interpreter to immediately start the next iteration of the loop and skip the remaining code block. When a continue statement is encountered, the program flow moves to the loop check expression immediately and if the condition remains true, then it starts the next iteration, otherwise the control comes out of the loop.\n\nExample\n\nThis example illustrates the use of a continue statement with a while loop. Notice how the continue statement is used to skip printing when the index held in variable $x$ reaches 5 −\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n<!--\nvar x = 1;\ndocument.write(\"Entering the loop<br /> \");\n```\nwhile (x < 10) {\n x = x + 1;\n if (x == 5) {\n continue; // skill rest of the loop body\n }\n document.write( x + \"<br />\");\n}\n\ndocument.write(\"Exiting the loop!<br />\");\n\n<!-->\n</script>\n\n<p>Set the variable to different value and then try...</p>\n</body>\n</html>\n\nOutput\n\nEntering the loop\n2\n3\n4\n6\n7\n8\n9\n10\nExiting the loop!\n\nUsing Labels to Control the Flow\n\nStarting from JavaScript 1.2, a label can be used with break and continue to control the flow more precisely. A label is simply an identifier followed by a colon (:) that is applied to a statement or a block of code. We will see two different examples to understand how to use labels with break and continue.\n\nNote – Line breaks are not allowed between the ‘continue’ or ‘break’ statement and its label name. Also, there should not be any other statement in between a label name and associated loop.\n\nTry the following two examples for a better understanding of Labels.\n\nExample 1\n\nThe following example shows how to implement Label with a break statement.\n\n<html>\n<body>\n\n<script type=\"text/javascript\">\n <!---\n document.write(\"Entering the loop!<br />\");\n outerloop: // This is the label name\n for (var i = 0; i < 5; i++)\n {\n document.write(\"Outerloop: \" + i + \"<br />\");\n innerloop:\n for (var j = 0; j < 5; j++)\n {\n if (j > 3 ) break ; // Quit the innermost loop\n if (i == 2) break innerloop; // Do the same thing\n if (i == 4) break outerloop; // Quit the outer loop\n document.write(\"Innerloop: \" + j + \" <br />\");\n }\n -->\n</script>\n\n</body>\n</html>\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n <!--\n document.write(\"Entering the loop!<br /> \");\n outerloop: // This is the label name\n\n for (var i = 0; i < 3; i++)\n {\n document.write(\"Outerloop: \" + i + \"<br />\");\n for (var j = 0; j < 5; j++)\n {\n if (j == 3){\n continue outerloop;\n }\n }\n }\n\ndocument.write(\"Exiting the loop!<br /> \");\n //--> \n\n</script>\n\n</body>\n</html>\n```\n\nOutput\n\nEntering the loop!\nOuterloop: 0\nInnerloop: 0\nInnerloop: 1\nInnerloop: 2\nInnerloop: 3\nOuterloop: 1\nInnerloop: 0\nInnerloop: 1\nInnerloop: 2\nInnerloop: 3\nOuterloop: 2\nOuterloop: 3\nInnerloop: 0\nInnerloop: 1\nInnerloop: 2\nInnerloop: 3\nOuterloop: 4\nExiting the loop!\n\nExample 2\n\n```html\n<html>\n<body>\n\n<script type=\"text/javascript\">\n <!--\n document.write(\"Entering the loop!<br /> \");\n outerloop: // This is the label name\n\n for (var i = 0; i < 3; i++)\n {\n document.write(\"Outerloop: \" + i + \"<br />\");\n for (var j = 0; j < 5; j++)\n {\n if (j == 3){\n continue outerloop;\n }\n }\n }\n\ndocument.write(\"Exiting the loop!<br /> \");\n //--> \n\n</script>\n\n</body>\n</html>\n```\n\nOutput\n\nEntering the loop!\nOuterloop: 0\nInnerloop: 0\nA function is a group of reusable code which can be called anywhere in your program. This eliminates the need of writing the same code again and again. It helps programmers in writing modular codes. Functions allow a programmer to divide a big program into a number of small and manageable functions.\n\nLike any other advanced programming language, JavaScript also supports all the features necessary to write modular code using functions. You must have seen functions like `alert()` and `write()` in the earlier chapters. We were using these functions again and again, but they had been written in core JavaScript only once.\n\nJavaScript allows us to write our own functions as well. This section explains how to write your own functions in JavaScript.\n\n**Function Definition**\n\nBefore we use a function, we need to define it. The most common way to define a function in JavaScript is by using the `function` keyword, followed by a unique function name, a list of parameters (that might be empty), and a statement block surrounded by curly braces.\n\n**Syntax**\n\nThe basic syntax is shown here.\n\n```html\n<script type=\"text/javascript\">\n <!--\n function functionname(parameters)\n {\n statements\n }\n //-->\n</script>\n```\n\n**Example**\n\nTry the following example. It defines a function called `sayHello` that takes no parameters –\n\n```html\n<script type=\"text/javascript\">\n <!--\n function sayHello()\n {\n alert(\"Hello there\");\n }\n //-->\n</script>\n```\n\n**Calling a Function**\n\nTo invoke a function somewhere later in the script, you would simply need to write the name of that function as shown in the following code.\n\n```html\n<html>\n```\nFunction Parameters\n\nTill now, we have seen functions without parameters. But there is a facility to pass different parameters while calling a function. These passed parameters can be captured inside the function and any manipulation can be done over those parameters. A function can take multiple parameters separated by comma.\n\nExample\n\nTry the following example. We have modified our `sayHello` function here. Now it takes two parameters.\nThe return Statement\n\nA JavaScript function can have an optional return statement. This is required if you want to return a value from a function. This statement should be the last statement in a function.\n\nFor example, you can pass two numbers in a function and then you can expect the function to return their multiplication in your calling program.\n\nExample\n\nTry the following example. It defines a function that takes two parameters and concatenates them before returning the resultant in the calling program.\n\n```\n<html>\n<head>\n <script type=\"text/javascript\">\n function concatenate(first, last)\n {\n var full;\n full = first + last;\n return full;\n }\n function secondFunction()\n {\n var result;\n result = concatenate('Zara', 'Ali');\n document.write(result);\n }\n </script>\n</head>\n<body>\n<p>Click the following button to call the function</p>\n<form>\n <input type=\"button\" onclick=\"secondFunction()\" value=\"Call Function\">\n</form>\n<p>Use different parameters inside the function and then try...</p>\n</body>\n</html>\n```\nThere is a lot to learn about JavaScript functions, however we have covered the most important concepts in this tutorial.\n\n- JavaScript Nested Functions\n- JavaScript Function( ) Constructor\n- JavaScript Function Literals\n\n## JAVASCRIPT - EVENTS\n\n### What is an Event ?\n\nJavaScript's interaction with HTML is handled through events that occur when the user or the browser manipulates a page.\n\nWhen the page loads, it is called an event. When the user clicks a button, that click too is an event. Other examples include events like pressing any key, closing a window, resizing a window, etc.\n\nDevelopers can use these events to execute JavaScript coded responses, which cause buttons to close windows, messages to be displayed to users, data to be validated, and virtually any other type of response imaginable.\n\nEvents are a part of the Document Object Model (DOM) Level 3 and every HTML element contains a set of events which can trigger JavaScript Code.\n\nPlease go through this small tutorial for a better understanding [HTML Event Reference](#). Here we will see a few examples to understand a relation between Event and JavaScript –\n\n### onclick Event Type\n\nThis is the most frequently used event type which occurs when a user clicks the left button of his mouse. You can put your validation, warning etc., against this event type.\n\n### Example\n\nTry the following example.\n\n```html\n<html>\n<head>\n\n <script type=\"text/javascript\">\n <!--\n function sayHello() {\n alert(\"Hello World\")\n }\n //--> \n </script>\n\n</head>\n\n<body>\n <p>Click the following button and see result</p>\n <form>\n```\n\n```html\n```\nonsubmit Event type\n\nonsubmit is an event that occurs when you try to submit a form. You can put your form validation against this event type.\n\nExample\n\nThe following example shows how to use onsubmit. Here we are calling a validate() function before submitting a form data to the webserver. If validate() function returns true, the form will be submitted, otherwise it will not submit the data.\n\nTry the following example.\n\n```\n<html>\n<head>\n\n<script type=\"text/javascript\">\n <!--\n function validation() {\n all validation goes here\n ........\n return either true or false\n }\n //--> \n</script>\n\n</head>\n<body>\n\n<form method=\"POST\" action=\"t.cgi\" onsubmit=\"return validate()\">\n ........\n <input type=\"submit\" value=\"Submit\" />\n</form>\n\n</body>\n</html>\n```\n\nonmouseover and onmouseout\n\nThese two event types will help you create nice effects with images or even with text as well. The onmouseover event triggers when you bring your mouse over any element and the onmouseout triggers when you move your mouse out from that element. Try the following example.\n\n```\n<html>\n<head>\n\n<script type=\"text/javascript\">\n <!--\n function validation() {\n all validation goes here\n ........\n return either true or false\n }\n //--> \n</script>\n\n</head>\n<body>\n\n<form method=\"POST\" action=\"t.cgi\" onsubmit=\"return validate()\">\n ........\n <input type=\"submit\" value=\"Submit\" />\n</form>\n\n</body>\n</html>\n```\nOutput\n\nHTML 5 Standard Events\n\nThe standard HTML 5 events are listed here for your reference. Here script indicates a Javascript function to be executed against that event.\n\n<table>\n<thead>\n<tr>\n<th>Attribute</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Offline</td>\n<td>script</td>\n<td>Triggers when the document goes offline</td>\n</tr>\n<tr>\n<td>Onabort</td>\n<td>script</td>\n<td>Triggers on an abort event</td>\n</tr>\n<tr>\n<td>onafterprint</td>\n<td>script</td>\n<td>Triggers after the document is printed</td>\n</tr>\n<tr>\n<td>onbeforeonload</td>\n<td>script</td>\n<td>Triggers before the document loads</td>\n</tr>\n<tr>\n<td>onbeforeprint</td>\n<td>script</td>\n<td>Triggers before the document is printed</td>\n</tr>\n<tr>\n<td>onblur</td>\n<td>script</td>\n<td>Triggers when the window loses focus</td>\n</tr>\n<tr>\n<td>oncanplay</td>\n<td>script</td>\n<td>Triggers when media can start play, but might has to stop for buffering</td>\n</tr>\n<tr>\n<td>oncanplaythrough</td>\n<td>script</td>\n<td>Triggers when media can be played to the end, without stopping for buffering</td>\n</tr>\n<tr>\n<td>onchange</td>\n<td>script</td>\n<td>Triggers when an element changes</td>\n</tr>\n<tr>\n<td>onclick</td>\n<td>script</td>\n<td>Triggers on a mouse click</td>\n</tr>\n<tr>\n<td>oncontextmenu</td>\n<td>script</td>\n<td>Triggers when a context menu is triggered</td>\n</tr>\n<tr>\n<td>Event</td>\n<td>Description</td>\n<td></td>\n</tr>\n<tr>\n<td>---------------</td>\n<td>-----------------------------------------------------------------------------</td>\n<td></td>\n</tr>\n<tr>\n<td>ondblclick</td>\n<td>Triggers on a mouse double-click</td>\n<td></td>\n</tr>\n<tr>\n<td>ondrag</td>\n<td>Triggers when an element is dragged</td>\n<td></td>\n</tr>\n<tr>\n<td>ondragend</td>\n<td>Triggers at the end of a drag operation</td>\n<td></td>\n</tr>\n<tr>\n<td>ondragenter</td>\n<td>Triggers when an element has been dragged to a valid drop target</td>\n<td></td>\n</tr>\n<tr>\n<td>ondragleave</td>\n<td>Triggers when an element is being dragged over a valid drop target</td>\n<td></td>\n</tr>\n<tr>\n<td>ondragover</td>\n<td>Triggers at the start of a drag operation</td>\n<td></td>\n</tr>\n<tr>\n<td>ondragstart</td>\n<td>Triggers at the start of a drag operation</td>\n<td></td>\n</tr>\n<tr>\n<td>ondrop</td>\n<td>Triggers when dragged element is being dropped</td>\n<td></td>\n</tr>\n<tr>\n<td>ondurationchange</td>\n<td>Triggers when the length of the media is changed</td>\n<td></td>\n</tr>\n<tr>\n<td>onemptied</td>\n<td>Triggers when a media resource element suddenly becomes empty.</td>\n<td></td>\n</tr>\n<tr>\n<td>onended</td>\n<td>Triggers when media has reach the end</td>\n<td></td>\n</tr>\n<tr>\n<td>onerror</td>\n<td>Triggers when an error occur</td>\n<td></td>\n</tr>\n<tr>\n<td>onfocus</td>\n<td>Triggers when the window gets focus</td>\n<td></td>\n</tr>\n<tr>\n<td>onformchange</td>\n<td>Triggers when a form changes</td>\n<td></td>\n</tr>\n<tr>\n<td>onforminput</td>\n<td>Triggers when a form gets user input</td>\n<td></td>\n</tr>\n<tr>\n<td>onhaschange</td>\n<td>Triggers when the document has change</td>\n<td></td>\n</tr>\n<tr>\n<td>oninput</td>\n<td>Triggers when an element gets user input</td>\n<td></td>\n</tr>\n<tr>\n<td>oninvalid</td>\n<td>Triggers when an element is invalid</td>\n<td></td>\n</tr>\n<tr>\n<td>onkeydown</td>\n<td>Triggers when a key is pressed</td>\n<td></td>\n</tr>\n<tr>\n<td>onkeypress</td>\n<td>Triggers when a key is pressed and released</td>\n<td></td>\n</tr>\n<tr>\n<td>onkeyup</td>\n<td>Triggers when a key is released</td>\n<td></td>\n</tr>\n<tr>\n<td>onload</td>\n<td>Triggers when the document loads</td>\n<td></td>\n</tr>\n<tr>\n<td>onloadeddata</td>\n<td>Triggers when media data is loaded</td>\n<td></td>\n</tr>\n<tr>\n<td>onloadedmetadata</td>\n<td>Triggers when the duration and other media data of a media element is loaded</td>\n<td></td>\n</tr>\n<tr>\n<td>onloadstart</td>\n<td>Triggers when the browser starts to load the media data</td>\n<td></td>\n</tr>\n<tr>\n<td>onmessage</td>\n<td>Triggers when the message is triggered</td>\n<td></td>\n</tr>\n<tr>\n<td>onmousedown</td>\n<td>Triggers when a mouse button is pressed</td>\n<td></td>\n</tr>\n<tr>\n<td>onmousemove</td>\n<td>Triggers when the mouse pointer moves</td>\n<td></td>\n</tr>\n<tr>\n<td>onmouseout</td>\n<td>Triggers when the mouse pointer moves out of an element</td>\n<td></td>\n</tr>\n<tr>\n<td>onmouseover</td>\n<td>Triggers when the mouse pointer moves over an element</td>\n<td></td>\n</tr>\n<tr>\n<td>onmouseup</td>\n<td>Triggers when a mouse button is released</td>\n<td></td>\n</tr>\n<tr>\n<td>onmousewheel</td>\n<td>Triggers when the mouse wheel is being rotated</td>\n<td></td>\n</tr>\n<tr>\n<td>onoffline</td>\n<td>Triggers when the document goes offline</td>\n<td></td>\n</tr>\n<tr>\n<td>Event</td>\n<td>Description</td>\n<td></td>\n</tr>\n<tr>\n<td>------------------</td>\n<td>-----------------------------------------------------------------------------</td>\n<td></td>\n</tr>\n<tr>\n<td>online</td>\n<td>Triggers when the document comes online</td>\n<td></td>\n</tr>\n<tr>\n<td>online</td>\n<td>Triggers when the document comes online</td>\n<td></td>\n</tr>\n<tr>\n<td>onpagehide</td>\n<td>Triggers when the window is hidden</td>\n<td></td>\n</tr>\n<tr>\n<td>onpageshow</td>\n<td>Triggers when the window becomes visible</td>\n<td></td>\n</tr>\n<tr>\n<td>onpause</td>\n<td>Triggers when media data is paused</td>\n<td></td>\n</tr>\n<tr>\n<td>onplay</td>\n<td>Triggers when media data is going to start playing</td>\n<td></td>\n</tr>\n<tr>\n<td>onplaying</td>\n<td>Triggers when media data has start playing</td>\n<td></td>\n</tr>\n<tr>\n<td>onpopstate</td>\n<td>Triggers when the window's history changes</td>\n<td></td>\n</tr>\n<tr>\n<td>onprogress</td>\n<td>Triggers when the browser is fetching the media data</td>\n<td></td>\n</tr>\n<tr>\n<td>onratechange</td>\n<td>Triggers when the media data's playing rate has changed</td>\n<td></td>\n</tr>\n<tr>\n<td>onreadystatechange</td>\n<td>Triggers when the ready-state changes</td>\n<td></td>\n</tr>\n<tr>\n<td>onredo</td>\n<td>Triggers when the document performs a redo</td>\n<td></td>\n</tr>\n<tr>\n<td>onresize</td>\n<td>Triggers when the window is resized</td>\n<td></td>\n</tr>\n<tr>\n<td>onscroll</td>\n<td>Triggers when an element's scrollbar is being scrolled</td>\n<td></td>\n</tr>\n<tr>\n<td>onseeked</td>\n<td>Triggers when a media element's seeking attribute is no longer true, and the seeking has ended</td>\n<td></td>\n</tr>\n<tr>\n<td>onseeking</td>\n<td>Triggers when a media element's seeking attribute is true, and the seeking has begun</td>\n<td></td>\n</tr>\n<tr>\n<td>onselect</td>\n<td>Triggers when an element is selected</td>\n<td></td>\n</tr>\n<tr>\n<td>oninstalled</td>\n<td>Triggers when there is an error in fetching media data</td>\n<td></td>\n</tr>\n<tr>\n<td>onstorage</td>\n<td>Triggers when a document loads</td>\n<td></td>\n</tr>\n<tr>\n<td>onsubmit</td>\n<td>Triggers when a form is submitted</td>\n<td></td>\n</tr>\n<tr>\n<td>onsuspend</td>\n<td>Triggers when the browser has been fetching media data, but stopped before the entire media file was fetched</td>\n<td></td>\n</tr>\n<tr>\n<td>ontimeupdate</td>\n<td>Triggers when media changes its playing position</td>\n<td></td>\n</tr>\n<tr>\n<td>onundo</td>\n<td>Triggers when a document performs an undo</td>\n<td></td>\n</tr>\n<tr>\n<td>onunload</td>\n<td>Triggers when the user leaves the document</td>\n<td></td>\n</tr>\n<tr>\n<td>onvolumechange</td>\n<td>Triggers when media changes the volume, also when volume is set to "mute"</td>\n<td></td>\n</tr>\n<tr>\n<td>onwaiting</td>\n<td>Triggers when media has stopped playing, but is expected to resume</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**What are Cookies?**\n\nWeb Browsers and Servers use HTTP protocol to communicate and HTTP is a stateless protocol. But for a commercial website, it is required to maintain session information among different pages. For example, one user registration ends after completing many pages. But how to maintain users' session information across all the web pages.\nIn many situations, using cookies is the most efficient method of remembering and tracking preferences, purchases, commissions, and other information required for better visitor experience or site statistics.\n\n**How It Works?**\n\nYour server sends some data to the visitor's browser in the form of a cookie. The browser may accept the cookie. If it does, it is stored as a plain text record on the visitor's hard drive. Now, when the visitor arrives at another page on your site, the browser sends the same cookie to the server for retrieval. Once retrieved, your server knows/remembers what was stored earlier.\n\nCookies are a plain text data record of 5 variable-length fields –\n\n- **Expires** – The date the cookie will expire. If this is blank, the cookie will expire when the visitor quits the browser.\n- **Domain** – The domain name of your site.\n- **Path** – The path to the directory or web page that set the cookie. This may be blank if you want to retrieve the cookie from any directory or page.\n- **Secure** – If this field contains the word \"secure\", then the cookie may only be retrieved with a secure server. If this field is blank, no such restriction exists.\n- **Name=Value** – Cookies are set and retrieved in the form of key-value pairs\n\nCookies were originally designed for CGI programming. The data contained in a cookie is automatically transmitted between the web browser and the web server, so CGI scripts on the server can read and write cookie values that are stored on the client.\n\nJavaScript can also manipulate cookies using the `cookie` property of the `Document` object. JavaScript can read, create, modify, and delete the cookies that apply to the current web page.\n\n**Storing Cookies**\n\nThe simplest way to create a cookie is to assign a string value to the `document.cookie` object, which looks like this.\n\n```javascript\ndocument.cookie = \"key1=value1;key2=value2;expires=date\";\n```\n\nHere the `expires` attribute is optional. If you provide this attribute with a valid date or time, then the cookie will expire on a given date or time and thereafter, the cookies' value will not be accessible.\n\n**Note** – Cookie values may not include semicolons, commas, or whitespace. For this reason, you may want to use the JavaScript `escape()` function to encode the value before storing it in the cookie. If you do this, you will also have to use the corresponding `unescape()` function when you read the cookie value.\n\n**Example**\n\nTry the following. It sets a customer name in an input cookie.\n\n```html\n<html>\n <head>\n <script type=\"text/javascript\">\n function WriteCookie() {\n if( document.myform.customer.value == \"\" ){\n alert(\"Enter some value!\");\n return;\n }\n cookievalue = escape(document.myform.customer.value) + \";\";\n document.cookie=\"name=\" + cookievalue;\n </script>\n </head>\n</html>\n```\nOutput\n\nNow your machine has a cookie called **name**. You can set multiple cookies using multiple key=value pairs separated by comma.\n\n### Reading Cookies\n\nReading a cookie is just as simple as writing one, because the value of the `document.cookie` object is the cookie. So you can use this string whenever you want to access the cookie. The `document.cookie` string will keep a list of name=value pairs separated by semicolons, where **name** is the name of a cookie and value is its string value.\n\nYou can use strings' **split()** function to break a string into key and values as follows –\n\n### Example\n\nTry the following example to get all the cookies.\n\n```html\n<html>\n<head>\n\n<script type=\"text/javascript\">\n//-->\nfunction ReadCookie()\n{\n var allcookies = document.cookie;\ndocument.write (\"All Cookies : \" + allcookies );\n\n // Get all the cookies pairs in an array\n cookiearray = allcookies.split (\";\");\n\n // Now take key value pair out of this array\n for (var i=0; i<cookiearray.length; i++){\n name = cookiearray[i].split (\"=\")[0];\n value = cookiearray[i].split (\"=\")[1];\ndocument.write (\"Key is : \" + name + \" and Value is : \" + value);\n }\n\n //--->\n</script>\n</head>\n<body>\n</body>\n</html>\n```\nNote – Here length is a method of Array class which returns the length of an array. We will discuss Arrays in a separate chapter. By that time, please try to digest it.\n\nNote – There may be some other cookies already set on your machine. The above code will display all the cookies set on your machine.\n\nSetting Cookies Expiry Date\n\nYou can extend the life of a cookie beyond the current browser session by setting an expiration date and saving the expiry date within the cookie. This can be done by setting the ‘expires’ attribute to a date and time.\n\nExample\n\nTry the following example. It illustrates how to extend the expiry date of a cookie by 1 Month.\n\n```html\n<html>\n<head>\n\n<script type=\"text/javascript\">\n!-->\nfunction WriteCookie()\n{\n var now = new Date();\n now.setMonth( now.getMonth() + 1 );\n cookievalue = escape(document.myform.customer.value) + \";\"\n \n document.cookie=\"name=\" + cookievalue;\n document.cookie = \"expires=\" + now.toUTCString() + \";\"\n document.write (\"Setting Cookies : \" + \"name=\" + cookievalue );\n\n //-->\n</script>\n\n</head>\n<body>\n\n<form name=\"formname\" action=\"\">\n Enter name: <input type=\"text\" name=\"customer\"/>\n <input type=\"button\" value=\"Set Cookie\" onclick=\"WriteCookie()\"/>\n</form>\n\n</body>\n</html>\n```\nDeleting a Cookie\n\nSometimes you will want to delete a cookie so that subsequent attempts to read the cookie return nothing. To do this, you just need to set the expiry date to a time in the past.\n\nExample\n\nTry the following example. It illustrates how to delete a cookie by setting its expiry date to one month behind the current date.\n\n```html\n<html>\n<head>\n <script type=\"text/javascript\">\n <!--\n function WriteCookie()\n {\n var now = new Date();\n now.setMonth( now.getMonth() - 1 );\n cookievalue = escape(document.myform.customer.value) + \";\"\n document.cookie=\"name\" + cookievalue;\n document.cookie = \"expires\" + now.toUTCString() + \";\"\n document.write(\"Setting Cookies : \" + \"name\" + cookievalue);\n }\n //-->\n </script>\n</head>\n<body>\n <form name=\"formname\" action=\"\">\n Enter name: <input type=\"text\" name=\"customer\"/>\n <input type=\"button\" value=\"Set Cookie\" onclick=\"WriteCookie()\"/>\n </form>\n</body>\n</html>\n```\nWhat is Page Redirection?\n\nYou might have encountered a situation where you clicked a URL to reach a page X but internally you were directed to another page Y. It happens due to page redirection. This concept is different from JavaScript Page Refresh.\n\nThere could be various reasons why you would like to redirect a user from the original page. We are listing down a few of the reasons –\n\n- You did not like the name of your domain and you are moving to a new one. In such a scenario, you may want to direct all your visitors to the new site. Here you can maintain your old domain but put a single page with a page redirection such that all your old domain visitors can come to your new domain.\n\n- You have built-up various pages based on browser versions or their names or may be based on different countries, then instead of using your server-side page redirection, you can use client-side page redirection to land your users on the appropriate page.\n\n- The Search Engines may have already indexed your pages. But while moving to another domain, you would not like to lose your visitors coming through search engines. So you can use client-side page redirection. But keep in mind this should not be done to fool the search engine, it could lead your site to get banned.\n\nHow Page Re-direction Works?\n\nThe implementations of Page-Redirection are as follows.\n\nExample 1\n\nIt is quite simple to do a page redirect using JavaScript at client side. To redirect your site visitors to a new page, you just need to add a line in your head section as follows.\n\n```html\n<html>\n<head>\n <script type=\"text/javascript\">\n function Redirect() {\n window.location=\"http://www.tutorialspoint.com\";\n }\n </script>\n</head>\n<body>\n <p>Click the following button, you will be redirected to home page.</p>\n <form>\n <input type=\"button\" value=\"Redirect Me\" onclick=\"Redirect()\" />\n </form>\n</body>\n</html>\n```\nExample 2\n\nYou can show an appropriate message to your site visitors before redirecting them to a new page. This would need a bit time delay to load a new page. The following example shows how to implement the same. Here setTimeout() is a built-in JavaScript function which can be used to execute another function after a given time interval.\n\n```html\n<html>\n<head>\n<script type=\"text/javascript\">\n <!--\n function Redirect()\n {\n window.location=\"http://www.tutorialspoint.com\";\n }\n\n document.write(\"You will be redirected to main page in 10 sec.\");\n setTimeout('Redirect()', 10000);\n //-->\n</script>\n</head>\n<body>\n</body>\n</html>\n```\n\nOutput\n\nYou will be redirected to tutorialspoint.com main page in 10 seconds!\n\nExample 3\n\nThe following example shows how to redirect your site visitors onto a different page based on their browsers.\n\n```html\n<html>\n<head>\n <script type=\"text/javascript\">\n```\n\nOutput\n\nYou will be redirected to tutorialspoint.com main page in 10 seconds!\nJavaScript supports three important types of dialog boxes. These dialog boxes can be used to raise an alert, or to get confirmation on any input or to have a kind of input from the users. Here we will discuss each dialog box one by one.\n\n**Alert Dialog Box**\n\nAn alert dialog box is mostly used to give a warning message to the users. For example, if one input field requires to enter some text but the user does not provide any input, then as a part of validation, you can use an alert box to give a warning message.\n\nNonetheless, an alert box can still be used for friendlier messages. Alert box gives only one button “OK” to select and proceed.\n\n**Example**\n\n```html\n<html>\n<head>\n\n <script type=\"text/javascript\">\n <!--\n function Warn() {\n alert(\"This is a warning message!\");\n document.write(\"This is a warning message!\");\n }\n //-->\n </script>\n\n</head>\n<body>\n <p>Click the following button to see the result: </p>\n <form>\n <input type=\"button\" value=\"Click Me\" onclick=\"Warn()\" />\n </form>\n</body>\n</html>\n```\n\n**Output**\n**Confirmation Dialog Box**\n\nA confirmation dialog box is mostly used to take user's consent on any option. It displays a dialog box with two buttons: **Cancel**.\n\nIf the user clicks on the OK button, the window method `confirm()` will return true. If the user clicks on the Cancel button, then `confirm()` returns false. You can use a confirmation dialog box as follows.\n\n**Output**\n\n```html\n<html>\n<head>\n <script type=\"text/javascript\">\n <!---\n function getConfirmation(){\n var retVal = confirm(\"Do you want to continue ?\");\n if( retVal == true ){\n document.write (\"User wants to continue!\");\n return true;\n }\n else{\n Document.write (\"User does not want to continue!\");\n return false;\n }\n } //-->\n </script>\n</head>\n<body>\n <p>Click the following button to see the result: </p>\n <form>\n <input type=\"button\" value=\"Click Me\" onclick=\"getConfirmation();\" />\n </form>\n</body>\n</html>\n```\n\n**Output**\n\nPrompt Dialog Box\nThe prompt dialog box is very useful when you want to pop-up a text box to get user input. Thus, it enables you to interact with the user. The user needs to fill in the field and then click OK.\n\nThis dialog box is displayed using a method called `prompt()` which takes two parameters: (i) a label which you want to display in the text box and (ii) a default string to display in the text box.\n\nThis dialog box has two buttons: OK and Cancel. If the user clicks the OK button, the window method `prompt()` will return the entered value from the text box. If the user clicks the Cancel button, the window method `prompt()` returns null.\n\n**Example**\n\nThe following example shows how to use a prompt dialog box −\n\n```html\n<html>\n<head>\n <script type=\"text/javascript\">\n <!--\n function getValue(){\n var retVal = prompt(\"Enter your name : \", \"your name here\");\n document.write(\"You have entered : \" + retVal);\n \n //-->\n </script>\n</head>\n<body>\n <p>Click the following button to see the result: </p>\n <form>\n <input type=\"button\" value=\"Click Me\" onclick=\"getValue();\" />\n </form>\n</body>\n</html>\n```\n\n**Output**\n\n`void` is an important keyword in JavaScript which can be used as a unary operator that appears before its single operand, which may be of any type. This operator specifies an expression to be evaluated without returning a value.\n\n**Syntax**\n\nThe syntax of `void` can be either of the following two −\n\n```html\n<head>\n <script type=\"text/javascript\">\n <!--\n </script>\n</head>\n```\nExample 1\n\nThe most common use of this operator is in a client-side *javascript:* URL, where it allows you to evaluate an expression for its side-effects without the browser displaying the value of the evaluated expression.\n\nHere the expression `alert('Warning!!!')` is evaluated but it is not loaded back into the current document –\n\n```html\n<html>\n<head>\n \n <script type=\"text/javascript\">\n <!---\n //-->\n </script>\n\n </head>\n \n <body>\n \n <p>Click the following, This won't react at all...</p>\n <a href=\"javascript:void(alert('Warning!!!'))\">Click me!</a>\n\n </body>\n</html>\n```\n\nOutput\n\n---\n\nExample 2\n\nTake a look at the following example. The following link does nothing because the expression \"0\" has no effect in JavaScript. Here the expression \"0\" is evaluated, but it is not loaded back into the current document.\n\n```html\n<html>\n<head>\n \n <script type=\"text/javascript\">\n <!---\n //-->\n </script>\n\n </head>\n</html>\n```\nExample 3\n\nAnother use of `void` is to purposely generate the `undefined` value as follows.\n\n```html\n<html>\n<head>\n <script type=\"text/javascript\">\n <!--\n function getValue(){\n var a,b,c;\n\n a = void ( b = 5, c = 7 );\n document.write('a = ' + a + ' b = ' + b + ' c = ' + c);\n }\n //-->}\n </script>\n</head>\n<body>\n \n <p>Click the following to see the result:</p>\n \n <form>\n <input type=\"button\" value=\"Click Me\" onclick=\"getValue();\" />\n </form>\n\n</body>\n</html>\n```\n\nOutput\n\n```\nClick the following to see the result:\n\nClick Me\n```\n\n```javascript\nfunction getValue()\n {var a,b,c;\n\n a = void ( b = 5, c = 7 );\n document.write('a = ' + a + ' b = ' + b + ' c = ' + c);\n }\n```\n\n```javascript\nClick me!\n```\n\n```javascript\nundefined\n```\n\n```javascript\nundefined\n```\n\n```javascript\nundefined\n```\n\n```javascript\nundefined\n```\nMany times you would like to place a button on your webpage to print the content of that web page via an actual printer. JavaScript helps you to implement this functionality using the `print` function of `window` object.\n\nThe JavaScript print function `window.print()` prints the current web page when executed. You can call this function directly using the `onclick` event as shown in the following example.\n\n**Example**\n\nTry the following example.\n\n```html\n<html>\n<head>\n <script type=\"text/javascript\">\n <!--\n //-->\n </script>\n </head>\n<body>\n <form>\n <input type=\"button\" value=\"Print\" onclick=\"window.print()\" />\n </form>\n</body>\n</html>\n```\n\n**Output**\n\nAlthough it serves the purpose of getting a printout, it is not a recommended way. A printer friendly page is really just a page with text, no images, graphics, or advertising.\n\nYou can make a page printer friendly in the following ways —\n\n- Make a copy of the page and leave out unwanted text and graphics, then link to that printer friendly page from the original. Check Example.\n- If you do not want to keep an extra copy of a page, then you can mark your printable text using proper comments like `<!-- PRINT STARTS HERE -->`.....`<!-- PRINT ENDS HERE -->` and then you can use PERL or any other script in the background to purge printable text and display for final printing. We at Tutorialspoint use this method to provide print facility to our site visitors. Check Example.\n\n**How to Print a Page**\n\nIf you don’t find the above facilities on a web page, then you can use the browser's standard toolbar to get print the web page. Follow the link as follows.\n\n- File → Print → Click OK → button.\nJavaScript is an Object Oriented Programming (OOP) language. A programming language can be called object-oriented if it provides four basic capabilities to developers –\n\n- **Encapsulation** – the capability to store related information, whether data or methods, together in an object.\n- **Aggregation** – the capability to store one object inside another object.\n- **Inheritance** – the capability of a class to rely upon another class (or number of classes) for some of its properties and methods.\n- **Polymorphism** – the capability to write one function or method that works in a variety of different ways.\n\nObjects are composed of attributes. If an attribute contains a function, it is considered to be a method of the object, otherwise the attribute is considered a property.\n\n### Object Properties\n\nObject properties can be any of the three primitive data types, or any of the abstract data types, such as another object. Object properties are usually variables that are used internally in the object's methods, but can also be globally visible variables that are used throughout the page.\n\nThe syntax for adding a property to an object is −\n\n```javascript\nobjectName.objectProperty = propertyValue;\n```\n\n**For example** – The following code gets the document title using the \"title\" property of the `document` object.\n\n```javascript\nvar str = document.title;\n```\n\n### Object Methods\n\nMethods are the functions that let the object do something or let something be done to it. There is a small difference between a function and a method – at a function is a standalone unit of statements and a method is attached to an object and can be referenced by the `this` keyword.\n\nMethods are useful for everything from displaying the contents of the object to the screen to performing complex mathematical operations on a group of local properties and parameters.\n\n**For example** – Following is a simple example to show how to use the `write()` method of `document` object to write any content on the document.\n\n```javascript\ndocument.write(\"This is test\");\n```\n\n### User-Defined Objects\n\nAll user-defined objects and built-in objects are descendants of an object called `Object`.\n\n### The new Operator\n\nThe `new` operator is used to create an instance of an object. To create an object, the `new` operator is followed by the constructor method.\n\nIn the following example, the constructor methods are `Object()`, `Array()`, and `Date()`. These constructors are built-in JavaScript functions.\n\n```javascript\nvar employee = new Object();\nvar books = new Array(\"C++\", \"Perl\", \"Java\");\nvar day = new Date(\"August 15, 1947\");\n```\n\n### The Object() Constructor\n\n---\n\nThis document provides an overview of JavaScript's object-oriented programming features, including encapsulation, aggregation, inheritance, and polymorphism. It explains how objects are composed of properties and methods, and how to add properties and call methods. The document also introduces the `new` operator for creating new objects and discusses the `Object()` constructor for creating a new object instance.\nA constructor is a function that creates and initializes an object. JavaScript provides a special constructor function called `Object()` to build the object. The return value of the `Object()` constructor is assigned to a variable.\n\nThe variable contains a reference to the new object. The properties assigned to the object are not variables and are not defined with the `var` keyword.\n\n**Example 1**\n\nTry the following example; it demonstrates how to create an Object.\n\n```html\n<html>\n<head>\n <title>User-defined objects</title>\n <script type=\"text/javascript\">\n var book = new Object(); // Create the object\n book.subject = \"Perl\"; // Assign properties to the object\n book.author = \"Mohtashim\";\n </script>\n</head>\n<body>\n <script type=\"text/javascript\">\n document.write(\"Book name is : \" + book.subject + \"<br>\");\n document.write(\"Book author is : \" + book.author + \"<br>\"现实);\n </script>\n</body>\n</html>\n```\n\n**Output**\n\nBook name is : Perl\nBook author is : Mohtashim\n\n**Example 2**\n\nThis example demonstrates how to create an object with a User-Defined Function. Here `this` keyword is used to refer to the object that has been passed to a function.\n\n```html\n<html>\n<head>\n <title>User-defined objects</title>\n <script type=\"text/javascript\">\n function book(title, author){\n this.title = title;\n this.author = author;\n }\n </script>\n</head>\n<body>\n <script type=\"text/javascript\">\n var myBook = new book(\"Perl\", \"Mohtashim\");\n document.write(\"Book title is : \" + myBook.title + \"<br>\");\n document.write(\"Book author is : \" + myBook.author + \"<br>\");\n </script>\n</body>\n</html>\n```\nDefining Methods for an Object\n\nThe previous examples demonstrate how the constructor creates the object and assigns properties. But we need to complete the definition of an object by assigning methods to it.\n\nExample\n\nTry the following example; it shows how to add a function along with an object.\n\n```\n<html>\n<head>\n<title>User-defined objects</title>\n\n<script type=\"text/javascript\">\n // Define a function which will work as a method\n function addPrice(amount){\n this.price = amount;\n }\n\n function book(title, author){\n this.title = title;\n this.author = author;\n this.addPrice = addPrice; // Assign that method as property.\n }\n</script>\n</head>\n<body>\n<script type=\"text/javascript\">\n var myBook = new book(\"Perl\", \"Mohtashim\");\n myBook.addPrice(100);\n\n document.write(\"Book title is : \"+myBook.title + \"<br>\");\n document.write(\"Book author is : \"+myBook.author + \"<br>\");\n document.write(\"Book price is : \"+myBook.price + \"<br>\");\n</script>\n</body>\n</html>\n```\n\nOutput\n\nBook title is : Perl\nBook author is : Mohtashim\nBook price is : 100\n\nThe 'with' Keyword\n\nThe 'with' keyword is used as a kind of shorthand for referencing an object's properties or methods.\n\nThe object specified as an argument to with becomes the default object for the duration of the block that follows. The properties and methods for the object can be used without naming the object.\n\nSyntax\nThe syntax for with object is as follows −\n\n```javascript\nwith (object){\n properties used without the object name and dot\n}\n```\n\n**Example**\n\nTry the following example.\n\n```html\n<html>\n<head>\n<title>User-defined objects</title>\n<script type=\"text/javascript\">\n // Define a function which will work as a method\n function addPrice(amount){\n with(this){\n price = amount;\n }\n }\n\n function book(title, author){\n this.title = title;\n this.author = author;\n this.price = 0;\n this.addPrice = addPrice; // Assign that method as property.\n }\n</script>\n</head>\n<body>\n<script type=\"text/javascript\">\n var myBook = new book(\"Perl\", \"Mohtashim\");\n myBook.addPrice(100);\n\n document.write(\"Book title is : \" + myBook.title + \"<br>\");\n document.write(\"Book author is : \" + myBook.author + \"<br>\");\n document.write(\"Book price is : \" + myBook.price + \"<br>\");\n</script>\n</body>\n</html>\n```\n\n**Output**\n\nBook title is : Perl\nBook author is : Mohtashim\nBook price is : 100\n\n**JavaScript Native Objects**\n\nJavaScript has several built-in or native objects. These objects are accessible anywhere in your program and will work the same way in any browser running in any operating system.\n\nHere is the list of all important JavaScript Native Objects −\n\n- [JavaScript Number Object](#)\n- [JavaScript Boolean Object](#)\n- [JavaScript String Object](#)\n- [JavaScript Array Object](#)\n- [JavaScript Date Object](#)\nThe **Number** object represents numerical data, either integers or floating-point numbers. In general, you do not need to worry about **Number** objects because the browser automatically converts number literals to instances of the number class.\n\n**Syntax**\n\nThe syntax for creating a **number** object is as follows –\n\n```javascript\nvar val = new Number(number);\n```\n\nIn the place of number, if you provide any non-number argument, then the argument cannot be converted into a number, it returns **NaN** (Not-a-Number).\n\n**Number Properties**\n\nHere is a list of each property and their description.\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>MAX_VALUE</strong></td>\n<td>The largest possible value a number in JavaScript can have 1.7976931348623157E+308</td>\n</tr>\n<tr>\n<td><strong>MIN_VALUE</strong></td>\n<td>The smallest possible value a number in JavaScript can have 5E-324</td>\n</tr>\n<tr>\n<td><strong>NaN</strong></td>\n<td>Equal to a value that is not a number.</td>\n</tr>\n<tr>\n<td><strong>NEGATIVE_INFINITY</strong></td>\n<td>A value that is less than MIN_VALUE.</td>\n</tr>\n<tr>\n<td><strong>POSITIVE_INFINITY</strong></td>\n<td>A value that is greater than MAX_VALUE</td>\n</tr>\n<tr>\n<td><strong>prototype</strong></td>\n<td>A static property of the Number object. Use the prototype property to assign new properties and methods to the Number object in the current document</td>\n</tr>\n<tr>\n<td><strong>constructor</strong></td>\n<td>Returns the function that created this object's instance. By default this is the Number object.</td>\n</tr>\n</tbody>\n</table>\n\nIn the following sections, we will take a few examples to demonstrate the properties of Number.\n\n**Number Methods**\n\nThe Number object contains only the default methods that are a part of every object's definition.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>Forces a number to display in exponential notation, even if the number is in</td>\n</tr>\n</tbody>\n</table>\n### JavaScript - The Number Object\n\nThe `Number` object is used for representing numeric values. JavaScript supports several methods for working with numbers, including:\n\n- `toExponential()`: Formats a number with a specific number of digits to the right of the decimal.\n- `toFixed()`: Formats a number with a specific number of digits to the right of the decimal.\n- `toLocaleString()`: Returns a string value version of the current number in a format that may vary according to a browser's local settings.\n- `toPrecision()`: Defines how many total digits (including digits to the left and right of the decimal) to display of a number.\n- `toString()`: Returns the string representation of the number's value.\n- `valueOf()`: Returns the number's value.\n\nIn the following sections, we will have a few examples to explain the methods of Number.\n\n---\n\n### JavaScript - The Boolean Object\n\nThe `Boolean` object represents two values, either \"true\" or \"false\". If `value` parameter is omitted or is 0, -0, null, false, `NaN`, undefined, or the empty string (\"\"), the object has an initial value of false.\n\n#### Syntax\n\nUse the following syntax to create a `boolean` object.\n\n```javascript\nvar val = new Boolean(value);\n```\n\n#### Boolean Properties\n\nHere is a list of the properties of Boolean object –\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>constructor</td>\n<td>Returns a reference to the Boolean function that created the object.</td>\n</tr>\n<tr>\n<td>prototype</td>\n<td>The prototype property allows you to add properties and methods to an object.</td>\n</tr>\n</tbody>\n</table>\n\nIn the following sections, we will have a few examples to illustrate the properties of Boolean object.\n\n#### Boolean Methods\n\nHere is a list of the methods of Boolean object and their description.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>toSource()</td>\n<td>Returns a string containing the source of the Boolean object; you can use this string to create an equivalent object.</td>\n</tr>\n</tbody>\n</table>\n**toString()**\n\nReturns a string of either \"true\" or \"false\" depending upon the value of the object.\n\n**valueOf()**\n\nReturns the primitive value of the Boolean object.\n\nIn the following sections, we will have a few examples to demonstrate the usage of the Boolean methods.\n\n---\n\n**JAVASCRIPT - THE STRINGS OBJECT**\n\nThe **String** object lets you work with a series of characters; it wraps Javascript's string primitive data type with a number of helper methods.\n\nAs JavaScript automatically converts between string primitives and String objects, you can call any of the helper methods of the String object on a string primitive.\n\n**Syntax**\n\nUse the following syntax to create a String object –\n\n```javascript\nvar val = new String(string);\n```\n\nThe **String** parameter is a series of characters that has been properly encoded.\n\n**String Properties**\n\nHere is a list of the properties of String object and their description.\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>constructor</td>\n<td>Returns a reference to the String function that created the object.</td>\n</tr>\n<tr>\n<td>length</td>\n<td>Returns the length of the string.</td>\n</tr>\n<tr>\n<td>prototype</td>\n<td>The prototype property allows you to add properties and methods to an object.</td>\n</tr>\n</tbody>\n</table>\n\nIn the following sections, we will have a few examples to demonstrate the usage of String properties.\n\n**String Methods**\n\nHere is a list of the methods available in String object along with their description.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>charAt()</td>\n<td>Returns the character at the specified index.</td>\n</tr>\n<tr>\n<td>charCodeAt()</td>\n<td>Returns a number indicating the Unicode value of the character at the given index.</td>\n</tr>\n</tbody>\n</table>\n### String Methods\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>concat()</code></td>\n<td>Combines the text of two strings and returns a new string.</td>\n</tr>\n<tr>\n<td><code>indexOf()</code></td>\n<td>Returns the index within the calling String object of the first occurrence of the specified value, or -1 if not found.</td>\n</tr>\n<tr>\n<td><code>lastIndexOf()</code></td>\n<td>Returns the index within the calling String object of the last occurrence of the specified value, or -1 if not found.</td>\n</tr>\n<tr>\n<td><code>localeCompare()</code></td>\n<td>Returns a number indicating whether a reference string comes before or after or is the same as the given string in sort order.</td>\n</tr>\n<tr>\n<td><code>match()</code></td>\n<td>Used to match a regular expression against a string.</td>\n</tr>\n<tr>\n<td><code>replace()</code></td>\n<td>Used to find a match between a regular expression and a string, and to replace the matched substring with a new substring.</td>\n</tr>\n<tr>\n<td><code>search()</code></td>\n<td>Executes the search for a match between a regular expression and a specified string.</td>\n</tr>\n<tr>\n<td><code>slice()</code></td>\n<td>Extracts a section of a string and returns a new string.</td>\n</tr>\n<tr>\n<td><code>split()</code></td>\n<td>Splits a String object into an array of strings by separating the string into substrings.</td>\n</tr>\n<tr>\n<td><code>substr()</code></td>\n<td>Returns the characters in a string beginning at the specified location through the specified number of characters.</td>\n</tr>\n<tr>\n<td><code>substring()</code></td>\n<td>Returns the characters in a string between two indexes into the string.</td>\n</tr>\n<tr>\n<td><code>toLocaleLowerCase()</code></td>\n<td>The characters within a string are converted to lower case while respecting the current locale.</td>\n</tr>\n<tr>\n<td><code>toLocaleUpperCase()</code></td>\n<td>The characters within a string are converted to upper case while respecting the current locale.</td>\n</tr>\n<tr>\n<td><code>toLowerCase()</code></td>\n<td>Returns the calling string value converted to lower case.</td>\n</tr>\n<tr>\n<td><code>toString()</code></td>\n<td>Returns a string representing the specified object.</td>\n</tr>\n<tr>\n<td><code>toUpperCase()</code></td>\n<td>Returns the calling string value converted to uppercase.</td>\n</tr>\n<tr>\n<td><code>valueOf()</code></td>\n<td>Returns the primitive value of the specified object.</td>\n</tr>\n</tbody>\n</table>\n\n### String HTML Wrappers\n\nN/A\nHere is a list of the methods that return a copy of the string wrapped inside an appropriate HTML tag.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>anchor()</td>\n<td>Creates an HTML anchor that is used as a hypertext target.</td>\n</tr>\n<tr>\n<td>big()</td>\n<td>Creates a string to be displayed in a big font as if it were in a <big> tag.</td>\n</tr>\n<tr>\n<td>blink()</td>\n<td>Creates a string to blink as if it were in a <blink> tag.</td>\n</tr>\n<tr>\n<td>bold()</td>\n<td>Creates a string to be displayed as bold as if it were in a <b> tag.</td>\n</tr>\n<tr>\n<td>fixed()</td>\n<td>Causes a string to be displayed in fixed-pitch font as if it were in a <tt> tag.</td>\n</tr>\n<tr>\n<td>fontcolor()</td>\n<td>Causes a string to be displayed in the specified color as if it were in a <font color="color"> tag.</td>\n</tr>\n<tr>\n<td>fontsize()</td>\n<td>Causes a string to be displayed in the specified font size as if it were in a <font size="size"> tag.</td>\n</tr>\n<tr>\n<td>italics()</td>\n<td>Causes a string to be italic, as if it were in an <i> tag.</td>\n</tr>\n<tr>\n<td>link()</td>\n<td>Creates an HTML hypertext link that requests another URL.</td>\n</tr>\n<tr>\n<td>small()</td>\n<td>Causes a string to be displayed in a small font, as if it were in a <small> tag.</td>\n</tr>\n<tr>\n<td>strike()</td>\n<td>Causes a string to be displayed as struck-out text, as if it were in a <strike> tag.</td>\n</tr>\n<tr>\n<td>sub()</td>\n<td>Causes a string to be displayed as a subscript, as if it were in a <sub> tag</td>\n</tr>\n<tr>\n<td>sup()</td>\n<td>Causes a string to be displayed as a superscript, as if it were in a <sup> tag</td>\n</tr>\n</tbody>\n</table>\n\nIn the following sections, we will have a few examples to demonstrate the usage of String methods.\n\n**JAVASCRIPT - THE ARRAYS OBJECT**\n\nThe **Array** object lets you store multiple values in a single variable. It stores a fixed-size sequential collection of elements of the same type. An array is used to store a collection of data, but it is often more useful to think of an array as a collection of variables of the same type.\n\n**Syntax**\nUse the following syntax to create an **Array** object –\n\n```javascript\nvar fruits = new Array( \"apple\", \"orange\", \"mango\" );\n```\n\nThe **Array** parameter is a list of strings or integers. When you specify a single numeric parameter with the Array constructor, you specify the initial length of the array. The maximum length allowed for an array is 4,294,967,295.\n\nYou can create array by simply assigning values as follows –\n\n```javascript\nvar fruits = [ \"apple\", \"orange\", \"mango\" ];\n```\n\nYou will use ordinal numbers to access and to set values inside an array as follows.\n\n- `fruits[0]` is the first element\n- `fruits[1]` is the second element\n- `fruits[2]` is the third element\n\n### Array Properties\n\nHere is a list of the properties of the Array object along with their description.\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>constructor</code></td>\n<td>Returns a reference to the array function that created the object.</td>\n</tr>\n<tr>\n<td><code>index</code></td>\n<td>The property represents the zero-based index of the match in the string input.</td>\n</tr>\n<tr>\n<td><code>input</code></td>\n<td>This property is only present in arrays created by regular expression matches.</td>\n</tr>\n<tr>\n<td><code>length</code></td>\n<td>Reflects the number of elements in an array.</td>\n</tr>\n<tr>\n<td><code>prototype</code></td>\n<td>The prototype property allows you to add properties and methods to an object.</td>\n</tr>\n</tbody>\n</table>\n\nIn the following sections, we will have a few examples to illustrate the usage of Array properties.\n\n### Array Methods\n\nHere is a list of the methods of the Array object along with their description.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>concat()</code></td>\n<td>Returns a new array comprised of this array joined with other array(s) and/or value(s).</td>\n</tr>\n<tr>\n<td><code>every()</code></td>\n<td>Returns true if every element in this array satisfies the provided testing function.</td>\n</tr>\n<tr>\n<td><code>filter()</code></td>\n<td>Creates a new array with all of the elements of this array for which the provided filtering function returns true.</td>\n</tr>\n<tr>\n<td><code>forEach()</code></td>\n<td>Calls a function for each element in the array.</td>\n</tr>\n<tr>\n<td>Method</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>------------</td>\n<td>---------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td><code>indexOf()</code></td>\n<td>Returns the first (least) index of an element within the array equal to the specified value, or -1 if none is found.</td>\n</tr>\n<tr>\n<td><code>join()</code></td>\n<td>Joins all elements of an array into a string.</td>\n</tr>\n<tr>\n<td><code>lastIndexOf()</code></td>\n<td>Returns the last (greatest) index of an element within the array equal to the specified value, or -1 if none is found.</td>\n</tr>\n<tr>\n<td><code>map()</code></td>\n<td>Creates a new array with the results of calling a provided function on every element in this array.</td>\n</tr>\n<tr>\n<td><code>pop()</code></td>\n<td>Removes the last element from an array and returns that element.</td>\n</tr>\n<tr>\n<td><code>push()</code></td>\n<td>Adds one or more elements to the end of an array and returns the new length of the array.</td>\n</tr>\n<tr>\n<td><code>reduce()</code></td>\n<td>Apply a function simultaneously against two values of the array (from left-to-right) as to reduce it to a single value.</td>\n</tr>\n<tr>\n<td><code>reduceRight()</code></td>\n<td>Apply a function simultaneously against two values of the array (from right-to-left) as to reduce it to a single value.</td>\n</tr>\n<tr>\n<td><code>reverse()</code></td>\n<td>Reverses the order of the elements of an array -- the first becomes the last, and the last becomes the first.</td>\n</tr>\n<tr>\n<td><code>shift()</code></td>\n<td>Removes the first element from an array and returns that element.</td>\n</tr>\n<tr>\n<td><code>slice()</code></td>\n<td>Extracts a section of an array and returns a new array.</td>\n</tr>\n<tr>\n<td><code>some()</code></td>\n<td>Returns true if at least one element in this array satisfies the provided testing function.</td>\n</tr>\n<tr>\n<td><code>toSource()</code></td>\n<td>Represents the source code of an object</td>\n</tr>\n<tr>\n<td><code>sort()</code></td>\n<td>Represents the source code of an object</td>\n</tr>\n<tr>\n<td><code>splice()</code></td>\n<td>Adds and/or removes elements from an array.</td>\n</tr>\n<tr>\n<td><code>toString()</code></td>\n<td>Returns a string representing the array and its elements.</td>\n</tr>\n<tr>\n<td><code>unshift()</code></td>\n<td>Adds one or more elements to the front of an array and returns the new length of the array.</td>\n</tr>\n</tbody>\n</table>\nThe Date object is a datatype built into the JavaScript language. Date objects are created with the\nnew Date( ) as shown below.\n\nOnce a Date object is created, a number of methods allow you to operate on it. Most methods\nsimply allow you to get and set the year, month, day, hour, minute, second, and millisecond fields\nof the object, using either local time or UTC (universal, or GMT) time.\n\nThe ECMAScript standard requires the Date object to be able to represent any date and time, to\nmillisecond precision, within 100 million days before or after 1/1/1970. This is a range of plus or\nminus 273,785 years, so JavaScript can represent date and time till the year 275755.\n\nSyntax\n\nYou can use any of the following syntaxes to create a Date object using Date() constructor.\n\n- new Date()\n- new Date(milliseconds)\n- new Date(datestring)\n- new Date(year, month, date[, hour, minute, second, millisecond ])\n\nNote − Parameters in the brackets are always optional.\n\nHere is a description of the parameters −\n\n- **No Argument** − With no arguments, the Date() constructor creates a Date object set to the\ncurrent date and time.\n\n- **milliseconds** − When one numeric argument is passed, it is taken as the internal numeric\nrepresentation of the date in milliseconds, as returned by the getTime() method. For\nexample, passing the argument 5000 creates a date that represents five seconds past\nmidnight on 1/1/70.\n\n- **datestring** − When one string argument is passed, it is a string representation of a date, in\nthe format accepted by the Date.parse() method.\n\n- **7 arguments** − To use the last form of the constructor shown above. Here is a description of\neach argument:\n\n - **year** − Integer value representing the year. For compatibility (in order to avoid the Y2K\n problem), you should always specify the year in full; use 1998, rather than 98.\n\n - **month** − Integer value representing the month, beginning with 0 for January to 11 for\n December.\n\n - **date** − Integer value representing the day of the month.\n\n - **hour** − Integer value representing the hour of the day (24-hour scale).\n\n - **minute** − Integer value representing the minute segment of a time reading.\n\n - **second** − Integer value representing the second segment of a time reading.\n\n - **millisecond** − Integer value representing the millisecond segment of a time reading.\n\nDate Properties\n\nHere is a list of the properties of the Date object along with their description.\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>constructor</td>\n<td>Specifies the function that creates an object's prototype.</td>\n</tr>\n</tbody>\n</table>\nThe prototype property allows you to add properties and methods to an object.\n\nIn the following sections, we will have a few examples to demonstrate the usage of different Date properties.\n\n**Date Methods**\n\nHere is a list of the methods used with `Date` and their description.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>Date()</code></td>\n<td>Returns today's date and time</td>\n</tr>\n<tr>\n<td><code>getDate()</code></td>\n<td>Returns the day of the month for the specified date according to local time.</td>\n</tr>\n<tr>\n<td><code>getDay()</code></td>\n<td>Returns the day of the week for the specified date according to local time.</td>\n</tr>\n<tr>\n<td><code>getFullYear()</code></td>\n<td>Returns the year of the specified date according to local time.</td>\n</tr>\n<tr>\n<td><code>getHours()</code></td>\n<td>Returns the hour in the specified date according to local time.</td>\n</tr>\n<tr>\n<td><code>getMilliseconds()</code></td>\n<td>Returns the milliseconds in the specified date according to local time.</td>\n</tr>\n<tr>\n<td><code>getMinutes()</code></td>\n<td>Returns the minutes in the specified date according to local time.</td>\n</tr>\n<tr>\n<td><code>getMonth()</code></td>\n<td>Returns the month in the specified date according to local time.</td>\n</tr>\n<tr>\n<td><code>getSeconds()</code></td>\n<td>Returns the seconds in the specified date according to local time.</td>\n</tr>\n<tr>\n<td><code>getTime()</code></td>\n<td>Returns the numeric value of the specified date as the number of milliseconds since January 1, 1970, 00:00:00 UTC.</td>\n</tr>\n<tr>\n<td><code>getTimezoneOffset()</code></td>\n<td>Returns the time-zone offset in minutes for the current locale.</td>\n</tr>\n<tr>\n<td><code>getUTCDate()</code></td>\n<td>Returns the day (date) of the month in the specified date according to universal time.</td>\n</tr>\n<tr>\n<td><code>getUTCDay()</code></td>\n<td>Returns the day of the week in the specified date according to universal time.</td>\n</tr>\n<tr>\n<td><code>getUTCFullYear()</code></td>\n<td>Returns the year in the specified date according to universal time.</td>\n</tr>\n<tr>\n<td>Method</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-------------------------</td>\n<td>------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>getUTCHours()</td>\n<td>Returns the hours in the specified date according to universal time.</td>\n</tr>\n<tr>\n<td>getUTCMilliseconds()</td>\n<td>Returns the milliseconds in the specified date according to universal time.</td>\n</tr>\n<tr>\n<td>getUTCMinutes()</td>\n<td>Returns the minutes in the specified date according to universal time.</td>\n</tr>\n<tr>\n<td>getUTCMonth()</td>\n<td>Returns the month in the specified date according to universal time.</td>\n</tr>\n<tr>\n<td>getUTCSeconds()</td>\n<td>Returns the seconds in the specified date according to universal time.</td>\n</tr>\n<tr>\n<td>getYear()</td>\n<td><strong>Deprecated</strong> - Returns the year in the specified date according to local time. Use getFullYear instead.</td>\n</tr>\n<tr>\n<td>setDate()</td>\n<td>Sets the day of the month for a specified date according to local time.</td>\n</tr>\n<tr>\n<td>setFullYear()</td>\n<td>Sets the full year for a specified date according to local time.</td>\n</tr>\n<tr>\n<td>setHours()</td>\n<td>Sets the hours for a specified date according to local time.</td>\n</tr>\n<tr>\n<td>setMilliseconds()</td>\n<td>Sets the milliseconds for a specified date according to local time.</td>\n</tr>\n<tr>\n<td>setMinutes()</td>\n<td>Sets the minutes for a specified date according to local time.</td>\n</tr>\n<tr>\n<td>setMonth()</td>\n<td>Sets the month for a specified date according to local time.</td>\n</tr>\n<tr>\n<td>setSeconds()</td>\n<td>Sets the seconds for a specified date according to local time.</td>\n</tr>\n<tr>\n<td>setTime()</td>\n<td>Sets the Date object to the time represented by a number of milliseconds since January 1, 1970, 00:00:00 UTC.</td>\n</tr>\n<tr>\n<td>setUTCDate()</td>\n<td>Sets the day of the month for a specified date according to universal time.</td>\n</tr>\n<tr>\n<td>setUTCFullYear()</td>\n<td>Sets the full year for a specified date according to universal time.</td>\n</tr>\n<tr>\n<td>setUTCHours()</td>\n<td>Sets the hour for a specified date according to universal time.</td>\n</tr>\n<tr>\n<td>setUTCMilliseconds()</td>\n<td>Sets the milliseconds for a specified date according to universal time.</td>\n</tr>\n</tbody>\n</table>\nsetUTCMinutes() \nSets the minutes for a specified date according to universal time.\n\nsetUTCMonth() \nSets the month for a specified date according to universal time.\n\nsetUTCSeconds() \nSets the seconds for a specified date according to universal time.\n\nsetYear() \n**Deprecated** - Sets the year for a specified date according to local time. Use setFullYear instead.\n\ntoDateString() \nReturns the \"date\" portion of the Date as a human-readable string.\n\ntoGMTString() \n**Deprecated** - Converts a date to a string, using the Internet GMT conventions. Use toUTCString instead.\n\ntoLocaleDateString() \nReturns the \"date\" portion of the Date as a string, using the current locale's conventions.\n\ntoLocaleFormat() \nConverts a date to a string, using a format string.\n\ntoLocaleString() \nConverts a date to a string, using the current locale's conventions.\n\ntoLocaleTimeString() \nReturns the \"time\" portion of the Date as a string, using the current locale's conventions.\n\ntoSource() \nReturns a string representing the source for an equivalent Date object; you can use this value to create a new object.\n\ntoString() \nReturns a string representing the specified Date object.\n\ntoTimeString() \nReturns the \"time\" portion of the Date as a human-readable string.\n\ntoUTCString() \nConverts a date to a string, using the universal time convention.\n\nvalueOf() \nReturns the primitive value of a Date object.\n\n**Date Static Methods**\n\nIn addition to the many instance methods listed previously, the Date object also defines two static methods. These methods are invoked through the Date() constructor itself.\n### JAVASCRIPT - THE MATH OBJECT\n\nThe **math** object provides you properties and methods for mathematical constants and functions. Unlike other global objects, **Math** is not a constructor. All the properties and methods of **Math** are static and can be called by using Math as an object without creating it.\n\nThus, you refer to the constant **pi** as **Math.PI** and you call the **sine** function as **Math.sin(x)**, where x is the method's argument.\n\n#### Syntax\n\nThe syntax to call the properties and methods of Math are as follows:\n\n```javascript\nvar pi_val = Math.PI;\nvar sine_val = Math.sin(30);\n```\n\n#### Math Properties\n\nHere is a list of all the properties of Math and their description.\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>E</strong></td>\n<td>Euler's constant and the base of natural logarithms, approximately 2.718.</td>\n</tr>\n<tr>\n<td><strong>LN2</strong></td>\n<td>Natural logarithm of 2, approximately 0.693.</td>\n</tr>\n<tr>\n<td><strong>LN10</strong></td>\n<td>Natural logarithm of 10, approximately 2.302.</td>\n</tr>\n<tr>\n<td><strong>LOG2E</strong></td>\n<td>Base 2 logarithm of E, approximately 1.442.</td>\n</tr>\n<tr>\n<td><strong>LOG10E</strong></td>\n<td>Base 10 logarithm of E, approximately 0.434.</td>\n</tr>\n<tr>\n<td><strong>PI</strong></td>\n<td>Ratio of the circumference of a circle to its diameter, approximately 3.14159.</td>\n</tr>\n<tr>\n<td><strong>SQRT1_2</strong></td>\n<td>Square root of 1/2; equivalently, 1 over the square root of 2, approximately 0.707.</td>\n</tr>\n<tr>\n<td><strong>SQRT2</strong></td>\n<td>Square root of 2, approximately 1.414.</td>\n</tr>\n</tbody>\n</table>\n\nIn the following sections, we will have a few examples to demonstrate the usage of Math properties.\n\n#### Math Methods\n\nHere is a list of the methods associated with Math object and their description.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Date.parse()</strong></td>\n<td>Parses a string representation of a date and time and returns the internal millisecond representation of that date.</td>\n</tr>\n<tr>\n<td><strong>Date.UTC()</strong></td>\n<td>Returns the millisecond representation of the specified UTC date and time.</td>\n</tr>\n</tbody>\n</table>\nabs() Returns the absolute value of a number.\nacos() Returns the arccosine (in radians) of a number.\nasin() Returns the arcsine (in radians) of a number.\natan() Returns the arctangent (in radians) of a number.\natan2() Returns the arctangent of the quotient of its arguments.\nceil() Returns the smallest integer greater than or equal to a number.\ncos() Returns the cosine of a number.\nexp() Returns \\( E^N \\), where \\( N \\) is the argument, and \\( E \\) is Euler's constant, the base of the natural logarithm.\nfloor() Returns the largest integer less than or equal to a number.\nlog() Returns the natural logarithm (base \\( E \\)) of a number.\nmax() Returns the largest of zero or more numbers.\nmin() Returns the smallest of zero or more numbers.\npow() Returns base to the exponent power, that is, base exponent.\nrandom() Returns a pseudo-random number between 0 and 1.\nround() Returns the value of a number rounded to the nearest integer.\nsin() Returns the sine of a number.\nsqrt() Returns the square root of a number.\ntan() Returns the tangent of a number.\ntoSource() Returns the string \"Math\".\n\nIn the following sections, we will have a few examples to demonstrate the usage of the methods associated with Math.\n\n### REGULAR EXPRESSIONS AND REGEXP OBJECT\n\nA regular expression is an object that describes a pattern of characters.\n\nThe JavaScript `RegExp` class represents regular expressions, and both `String` and `RegExp` define methods that use regular expressions to perform powerful pattern-matching and search-and-replace functions on text.\n\n**Syntax**\n\nA regular expression could be defined with the `RegExp()` constructor, as follows –\n\n```javascript\nvar pattern = new RegExp(pattern, attributes);\n```\n\nor simply\n\n```javascript\nvar pattern = /pattern/attributes;\n```\n\nHere is the description of the parameters –\n\n- **pattern** – A string that specifies the pattern of the regular expression or another regular expression.\n- **attributes** – An optional string containing any of the \"g\", \"i\", and \"m\" attributes that specify global, case-insensitive, and multiline matches, respectively.\n\n**Brackets**\n\nBrackets ([ ]) have a special meaning when used in the context of regular expressions. They are used to find a range of characters.\n\n<table>\n<thead>\n<tr>\n<th>Expression</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>[...]</td>\n<td>Any one character between the brackets.</td>\n</tr>\n<tr>\n<td>[^...]</td>\n<td>Any one character not between the brackets.</td>\n</tr>\n<tr>\n<td>[0-9]</td>\n<td>It matches any decimal digit from 0 through 9.</td>\n</tr>\n<tr>\n<td>[a-z]</td>\n<td>It matches any character from lowercase a through lowercase z.</td>\n</tr>\n<tr>\n<td>[A-Z]</td>\n<td>It matches any character from uppercase A through uppercase Z.</td>\n</tr>\n<tr>\n<td>[a-Z]</td>\n<td>It matches any character from lowercase a through uppercase Z.</td>\n</tr>\n</tbody>\n</table>\n\nThe ranges shown above are general; you could also use the range [0-3] to match any decimal digit ranging from 0 through 3, or the range [b-v] to match any lowercase character ranging from b through v.\n\n**Quantifiers**\n\nThe frequency or position of bracketed character sequences and single characters can be denoted by a special character. Each special character has a specific connotation. The +, *, ?, and $ flags all follow a character sequence.\n\n<table>\n<thead>\n<tr>\n<th>Expression</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>p+</td>\n<td>It matches any string containing at least one p.</td>\n</tr>\n<tr>\n<td>p*</td>\n<td>It matches any string containing zero or more p's.</td>\n</tr>\n<tr>\n<td>p?</td>\n<td>It matches any string containing one or more p's.</td>\n</tr>\n<tr>\n<td>p{N}</td>\n<td>It matches any string containing a sequence of N p's</td>\n</tr>\n<tr>\n<td>p{2,3}</td>\n<td>It matches any string containing a sequence of two or three p's.</td>\n</tr>\n<tr>\n<td>p{2, }</td>\n<td>It matches any string containing a sequence of at least two p's.</td>\n</tr>\n<tr>\n<td>p$</td>\n<td>It matches any string with p at the end of it.</td>\n</tr>\n<tr>\n<td>^p</td>\n<td>It matches any string with p at the beginning of it.</td>\n</tr>\n</tbody>\n</table>\n\n**Examples**\n\nFollowing examples explain more about matching characters.\n\n<table>\n<thead>\n<tr>\n<th>Expression</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>[^a-zA-Z]</td>\n<td>It matches any string not containing any of the characters ranging from a through z and A through Z.</td>\n</tr>\n<tr>\n<td>p.p</td>\n<td>It matches any string containing p, followed by any character, in turn followed by another p.</td>\n</tr>\n</tbody>\n</table>\n^.{2}$ It matches any string containing exactly two characters.\n<b>(.*)</b> It matches any string enclosed within <b> and </b>.\np(hp)* It matches any string containing a p followed by zero or more instances of the sequence hp.\n\n**Literal characters**\n\n<table>\n<thead>\n<tr>\n<th>Character</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Alphanumeric</td>\n<td>Itself</td>\n</tr>\n<tr>\n<td>\\0</td>\n<td>The NUL character (\\u0000)</td>\n</tr>\n<tr>\n<td>\\t</td>\n<td>Tab (\\u0009)</td>\n</tr>\n<tr>\n<td>\\n</td>\n<td>Newline (\\u000A)</td>\n</tr>\n<tr>\n<td>\\v</td>\n<td>Vertical tab (\\u000B)</td>\n</tr>\n<tr>\n<td>\\f</td>\n<td>Form feed (\\u000C)</td>\n</tr>\n<tr>\n<td>\\r</td>\n<td>Carriage return (\\u000D)</td>\n</tr>\n<tr>\n<td>\\xnn</td>\n<td>The Latin character specified by the hexadecimal number nn; for example, \\x0A is the same as \\n</td>\n</tr>\n<tr>\n<td>\\uxxxx</td>\n<td>The Unicode character specified by the hexadecimal number xxxx; for example, \\u0009 is the same as \\t</td>\n</tr>\n<tr>\n<td>\\cX</td>\n<td>The control character ^X; for example, \\cJ is equivalent to the newline character \\n</td>\n</tr>\n</tbody>\n</table>\n\n**Metacharacters**\n\nA metacharacter is simply an alphabetical character preceded by a backslash that acts to give the combination a special meaning.\n\nFor instance, you can search for a large sum of money using the \\d metacharacter: /((\\d)+)000/, Here \\d will search for any string of numerical character.\n\nThe following table lists a set of metacharacters which can be used in PERL Style Regular Expressions.\n\n<table>\n<thead>\n<tr>\n<th>Character</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>.</td>\n<td>a single character</td>\n</tr>\n<tr>\n<td>\\s</td>\n<td>a whitespace character (space, tab, newline)</td>\n</tr>\n<tr>\n<td>\\S</td>\n<td>non-whitespace character</td>\n</tr>\n<tr>\n<td>\\d</td>\n<td>a digit (0-9)</td>\n</tr>\n<tr>\n<td>\\D</td>\n<td>a non-digit</td>\n</tr>\n<tr>\n<td>\\w</td>\n<td>a word character (a-z, A-Z, 0-9, _)</td>\n</tr>\n<tr>\n<td>\\W</td>\n<td>a non-word character</td>\n</tr>\n<tr>\n<td>[b]</td>\n<td>a literal backspace (special case).</td>\n</tr>\n</tbody>\n</table>\n[aeiou] matches a single character in the given set\n[^aeiou] matches a single character outside the given set\n(foo|bar|baz) matches any of the alternatives specified\n\n**Modifiers**\n\nSeveral modifiers are available that can simplify the way you work with *regexps*, like case sensitivity, searching in multiple lines, etc.\n\n<table>\n<thead>\n<tr>\n<th>Modifier</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>i</td>\n<td>Perform case-insensitive matching.</td>\n</tr>\n<tr>\n<td>m</td>\n<td>Specifies that if the string has newline or carriage return characters, the ^ and $ operators will now match against a newline boundary, instead of a string boundary</td>\n</tr>\n<tr>\n<td>g</td>\n<td>Performs a global match that is, find all matches rather than stopping after the first match.</td>\n</tr>\n</tbody>\n</table>\n\n**RegExp Properties**\n\nHere is a list of the properties associated with RegExp and their description.\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>constructor</td>\n<td>Specifies the function that creates an object's prototype.</td>\n</tr>\n<tr>\n<td>global</td>\n<td>Specifies if the "g" modifier is set.</td>\n</tr>\n<tr>\n<td>ignoreCase</td>\n<td>Specifies if the "i" modifier is set.</td>\n</tr>\n<tr>\n<td>lastIndex</td>\n<td>The index at which to start the next match.</td>\n</tr>\n<tr>\n<td>multiline</td>\n<td>Specifies if the "m" modifier is set.</td>\n</tr>\n<tr>\n<td>source</td>\n<td>The text of the pattern.</td>\n</tr>\n</tbody>\n</table>\n\nIn the following sections, we will have a few examples to demonstrate the usage of RegExp properties.\n\n**RegExp Methods**\n\nHere is a list of the methods associated with RegExp along with their description.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>exec()</td>\n<td>Executes a search for a match in its string parameter.</td>\n</tr>\n<tr>\n<td>test()</td>\n<td>Tests for a match in its string parameter.</td>\n</tr>\n<tr>\n<td>toSource()</td>\n<td>Returns an object literal representing the specified object; you can use this value to create a new object.</td>\n</tr>\n<tr>\n<td>toString()</td>\n<td>Returns a string representing the specified object.</td>\n</tr>\n</tbody>\n</table>\nIn the following sections, we will have a few examples to demonstrate the usage of RegExp methods.\n\n**JAVASCRIPT - DOCUMENT OBJECT MODEL OR DOM**\n\nEvery web page resides inside a browser window which can be considered as an object.\n\nA Document object represents the HTML document that is displayed in that window. The Document object has various properties that refer to other objects which allow access to and modification of document content.\n\nThe way a document content is accessed and modified is called the **Document Object Model**, or **DOM**. The Objects are organized in a hierarchy. This hierarchical structure applies to the organization of objects in a Web document.\n\n- **Window object** – Top of the hierarchy. It is the outmost element of the object hierarchy.\n- **Document object** – Each HTML document that gets loaded into a window becomes a document object. The document contains the contents of the page.\n- **Form object** – Everything enclosed in the `<form>...</form>` tags sets the form object.\n- **Form control elements** – The form object contains all the elements defined for that object such as text fields, buttons, radio buttons, and checkboxes.\n\nHere is a simple hierarchy of a few important objects –\n\n```\nWindow\n | frame parent self top\n +------------------------\n | history document location\n +------------------------\n | link form anchor\n +------------------------\n | radio textarea button text checkbox\n +------------------------\n | password reset select\n +------------------------\n | option\n```\n\nThere are several DOMs in existence. The following sections explain each of these DOMs in detail and describe how you can use them to access and modify document content.\n\n- **The Legacy DOM** – This is the model which was introduced in early versions of JavaScript language. It is well supported by all browsers, but allows access only to certain key portions of documents, such as forms, form elements, and images.\n\n- **The W3C DOM** – This document object model allows access and modification of all document content and is standardized by the World Wide Web Consortium (W3C). This model is supported by almost all the modern browsers.\n\n- **The IE4 DOM** – This document object model was introduced in Version 4 of Microsoft's Internet Explorer browser. IE 5 and later versions include support for most basic W3C DOM features.\n\n**DOM compatibility**\n\nIf you want to write a script with the flexibility to use either W3C DOM or IE 4 DOM depending on their availability, then you can use a capability-testing approach that first checks for the existence of a method or property to determine whether the browser has the capability you desire. For\nThere are three types of errors in programming: (a) Syntax Errors, (b) Runtime Errors, and (c) Logical Errors.\n\nSyntax Errors\n\nSyntax errors, also called parsing errors, occur at compile time in traditional programming languages and at interpret time in JavaScript.\n\nFor example, the following line causes a syntax error because it is missing a closing parenthesis.\n\n```<script type=\"text/javascript\">\n <!--\n window.print();\n //-->\n</script>```\n\nWhen a syntax error occurs in JavaScript, only the code contained within the same thread as the syntax error is affected and the rest of the code in other threads gets executed assuming nothing in them depends on the code containing the error.\n\nRuntime Errors\n\nRuntime errors, also called exceptions, occur during execution (after compilation/interpretation).\n\nFor example, the following line causes a runtime error because here the syntax is correct, but at runtime, it is trying to call a method that does not exist.\n\n```<script type=\"text/javascript\">\n <!--\n window.printme();\n //-->\n</script>```\n\nExceptions also affect the thread in which they occur, allowing other JavaScript threads to continue normal execution.\n\nLogical Errors\n\nLogic errors can be the most difficult type of errors to track down. These errors are not the result of a syntax or runtime error. Instead, they occur when you make a mistake in the logic that drives your script and you do not get the result you expected.\n\nYou cannot catch those errors, because it depends on your business requirement what type of logic you want to put in your program.\n\nThe try...catch...finally Statement\n\nThe latest versions of JavaScript added exception handling capabilities. JavaScript implements the try...catch...finally construct as well as the throw operator to handle exceptions.\nYou can catch programmer-generated and runtime exceptions, but you cannot catch JavaScript syntax errors.\n\nHere is the try...catch...finally block syntax –\n\n```html\n<script type=\"text/javascript\">\n<!--\ntry {\n // Code to run\n [break;]\n}\n\n catch ( e ) {\n // Code to run if an exception occurs\n [break;]\n }\n\n [ finally {\n // Code that is always executed regardless of\n // an exception occurring\n } ]\n//-->\n</script>\n```\n\nThe try block must be followed by either exactly one catch block or one finally block (or one of both). When an exception occurs in the try block, the exception is placed in `e` and the catch block is executed. The optional finally block executes unconditionally after try/catch.\n\n**Examples**\n\nHere is an example where we are trying to call a non-existing function which in turn is raising an exception. Let us see how it behaves without try...catch –\n\n```html\n<html>\n<head>\n <script type=\"text/javascript\">\n <!--\n function myFunc()\n {\n var a = 100;\n alert(\"Value of variable a is : \" + a);\n }\n //-->\n </script>\n</head>\n<body>\n <p>Click the following to see the result:</p>\n <form>\n <input type=\"button\" value=\"Click Me\" onclick=\"myFunc();\" />\n </form>\n</body>\n</html>\n```\n\n**Output**\nNow let us try to catch this exception using `try...catch` and display a user-friendly message. You can also suppress this message, if you want to hide this error from a user.\n\n```html\n<html>\n <head>\n <script type=\"text/javascript\">\n <!---\n function myFunc()\n {\n var a = 100;\n try {\n alert(\"Value of variable a is : \" + a);\n }\n catch (e) {\n alert(\"Error: \" + e.description);\n }\n //--> </script>\n </head>\n <body>\n <p>Click the following to see the result:</p>\n <form>\n <input type=\"button\" value=\"Click Me\" onclick=\"myFunc();\" />\n </form>\n </body>\n</html>\n```\n\n**Output**\n\nYou can use `finally` block which will always execute unconditionally after the try/catch. Here is an example.\n\n```html\n<html>\n <head>\n <script type=\"text/javascript\">\n function myFunc()\n {\n var a = 100;\n try {\n alert(\"Value of variable a is : \" + a);\n }\n catch (e) {\n alert(\"Error: \" + e.description);\n }\n }\n </script>\n </head>\n <body>\n <p>Click the following to see the result:</p>\n <form>\n <input type=\"button\" value=\"Click Me\" onclick=\"myFunc();\" />\n </form>\n </body>\n</html>\n```\n<html>\n<head>\n<script type=\"text/javascript\">\n <!--\nfunction myFunc()\n{\n var a = 100;\n try {\n alert(\"Value of variable a is : \" + a);\n }\n catch ( e ) {\n alert(\"Error: \" + e.description);\n }\n finally {\n alert(\"Finally block will always execute!\" );\n }\n //-->\n</script>\n</head>\n<body>\n<p>Click the following to see the result:</p>\n<form>\n<input type=\"button\" value=\"Click Me\" onclick=\"myFunc();\" />\n</form>\n</body>\n</html>\n\n**Output**\n\n![Output Image]\n\n**The throw Statement**\n\nYou can use **throw** statement to raise your built-in exceptions or your customized exceptions. Later these exceptions can be captured and you can take an appropriate action.\n\n**Example**\n\nThe following example demonstrates how to use a **throw** statement.\n\n```html\n<html>\n<head>\n</head>\n<body>\n<script type=\"text/javascript\">\n <!--\nfunction myFunc()\n{\n var a = 100;\n var b = 0;\n try{\n if ( b == 0 )\n```\nthrow( \"Divide by zero error.\" );\n}\nelse\n{\n var c = a / b;\n}\n\ncatch ( e ) {\n alert(\"Error: \"+ e);\n}\n\n//-->\n</script>\n</head>\n<body>\n<p>Click the following to see the result:</p>\n<form>\n <input type=\"button\" value=\"Click Me\" onclick=\"myFunc();\" />\n</form>\n</body>\n</html>\n\nOutput\n\nYou can raise an exception in one function using a string, integer, Boolean, or an object and then you can capture that exception either in the same function as we did above, or in another function using a try...catch block.\n\n**The onerror() Method**\n\nThe onerror event handler was the first feature to facilitate error handling in JavaScript. The error event is fired on the window object whenever an exception occurs on the page.\nThe `onerror` event handler provides three pieces of information to identify the exact nature of the error –\n\n- **Error message** – The same message that the browser would display for the given error\n- **URL** – The file in which the error occurred\n- **Line number** – The line number in the given URL that caused the error\n\nHere is the example to show how to extract this information.\n\n### Example\n\n```html\n<html>\n <head>\n <script type=\"text/javascript\">\n <!--\n window.onerror = function (msg, url, line) {\n alert(\"Message : \" + msg);\n alert(\"url : \" + url);\n alert(\"Line number : \" + line);\n }\n //-->\n </script>\n </head>\n <body>\n <p>Click the following to see the result:</p>\n <form>\n <input type=\"button\" value=\"Click Me\" onclick=\"myFunc();\" />\n </form>\n </body>\n</html>\n```\n\n**Output**\nYou can display extracted information in whatever way you think it is better.\n\nYou can use an `onerror` method, as shown below, to display an error message in case there is any problem in loading an image.\n\n```html\n<img src=\"myimage.gif\" onerror=\"alert('An error occurred loading the image.')\" />\n```\n\nYou can use `onerror` with many HTML tags to display appropriate messages in case of errors.\n\n---\n\n**JAVASCRIPT - FORM VALIDATION**\n\nForm validation normally used to occur at the server, after the client had entered all the necessary data and then pressed the Submit button. If the data entered by a client was incorrect or was simply missing, the server would have to send all the data back to the client and request that the form be resubmitted with correct information. This was really a lengthy process which used to put a lot of burden on the server.\n\nJavaScript provides a way to validate form's data on the client's computer before sending it to the web server. Form validation generally performs two functions.\n\n- **Basic Validation** — First of all, the form must be checked to make sure all the mandatory fields are filled in. It would require just a loop through each field in the form and check for data.\n\n- **Data Format Validation** — Secondly, the data that is entered must be checked for correct form and value. Your code must include appropriate logic to test correctness of data.\n\n**Example**\n\nWe will take an example to understand the process of validation. Here is a simple form in html format.\n\n```html\n<html>\n\n<head>\n <title>Form Validation</title>\n\n <script type=\"text/javascript\">\n // Form validation code will come here.\n </script>\n\n</head>\n\n<body>\n <form action=\"/cgi-bin/test.cgi\" name=\"myForm\" onsubmit=\"return(validate());\">\n <table cellspacing=\"2\" cellpadding=\"2\" border=\"1\">\n <tr>\n <td align=\"right\">Name</td>\n <td><input type=\"text\" name=\"Name\" /></td>\n </tr>\n </table>\n </form>\n</body>\n</html>\n```\nBasic Form Validation\n\nFirst let us see how to do a basic form validation. In the above form, we are calling `validate()` to validate data when `onsubmit` event is occurring. The following code shows the implementation of this `validate()` function.\n\n```javascript\n<!-- Form validation code will come here. -->\nfunction validate()\n{\n if( document.myForm.Name.value == \"\" )\n {\n alert( \"Please provide your name!\" );\n document.myForm.Name.focus();\n return false;\n }\n\n if( document.myForm.EMail.value == \"\" )\n {\n alert( \"Please provide your Email!\" );\n }\n```\nData Format Validation\n\nNow we will see how we can validate our entered form data before submitting it to the web server.\n\nThe following example shows how to validate an entered email address. An email address must contain at least a ‘@’ sign and a dot (.). Also, the ‘@’ must not be the first character of the email address, and the last dot must at least be one character after the ‘@’ sign.\n\nExample\n\nTry the following code for email validation.\n\n```javascript\nfunction validateEmail()\n{\n var emailID = document.myForm.EMail.value;\natpos = emailID.indexOf(\"@\");\ndotpos = emailID.lastIndexOf(\".\");\n\n if (atpos < 1 || (dotpos - atpos < 2))\n {\n alert(\"Please enter correct email ID\")\ndocument.myForm.EMail.focus();\nreturn false;\n }\nreturn( true );\n\nreturn false;\n}\n```\n\nJAVASCRIPT - ANIMATION\n\nYou can use JavaScript to create a complex animation having, but not limited to, the following elements –\n\n- Fireworks\n- Fade Effect\n- Roll-in or Roll-out\n- Page-in or Page-out\n- Object movements\n\nThis tutorial provides a basic understanding of how to use JavaScript to create an animation.\n\nJavaScript can be used to move a number of DOM elements (`<img />`, `<div>` or any other HTML element) around the page according to some sort of pattern determined by a logical equation or function.\n\nJavaScript provides the following two functions to be frequently used in animation programs.\n\n- `setTimeout(function, duration)` – This function calls `function` after `duration` milliseconds from now.\n- `setInterval(function, duration)` – This function calls `function` after every `duration` milliseconds.\n- `clearTimeout(setTimeout_variable)` – This function calls clears any timer set by the `setTimeout()` functions.\n\nJavaScript can also set a number of attributes of a DOM object including its position on the screen. You can set `top` and `left` attribute of an object to position it anywhere on the screen. Here is its syntax.\n\n```javascript\n// Set distance from left edge of the screen.\nobject.style.left = distance in pixels or points;\n\nor\n\n// Set distance from top edge of the screen.\nobject.style.top = distance in pixels or points;\n```\n\n### Manual Animation\n\nSo let's implement one simple animation using DOM object properties and JavaScript functions as follows. The following list contains different DOM methods.\n\n- We are using the JavaScript function `getElementById()` to get a DOM object and then assigning it to a global variable `imgObj`.\n- We have defined an initialization function `init()` to initialize `imgObj` where we have set its `position` and `left` attributes.\n- We are calling initialization function at the time of window load.\n- Finally, we are calling `moveRight()` function to increase the left distance by 10 pixels. You could also set it to a negative value to move it to the left side.\n\n### Example\n\nTry the following example.\n\n```html\n<html>\n <head>\n <title>JavaScript Animation</title>\n </head>\n <script type=\"text/javascript\">\n var imgObj = null;\n\n function init(){\n imgObj = document.getElementById('myImage');\n imgObj.style.position = 'relative';\n imgObj.style.left = '0px';\n }\n </script>\n</html>\n```\nfunction moveRight()\n imgObj.style.left = parseInt(imgObj.style.left) + 10 + 'px';\n}\n\nwindow.onload = init;\n//-->\n</script>\n</head>\n<body>\n<form>\n <img />\n <p>Click button below to move the image to right</p>\n <input type=\"button\" value=\"Click Me\" onclick=\"moveRight();\" />\n</form>\n</body>\n</html>\n\nAutomated Animation\n\nIn the above example, we saw how an image moves to right with every click. We can automate this process by using the JavaScript function `setTimeout()` as follows –\n\nHere we have added more methods. So let's see what is new here –\n\n- The `moveRight()` function is calling `setTimeout()` function to set the position of `imgObj`.\n- We have added a new function `stop()` to clear the timer set by `setTimeout()` function and to set the object at its initial position.\n\nExample\n\nTry the following example code.\n\n```html\n<html>\n <head>\n <title>JavaScript Animation</title>\n <script type=\"text/javascript\">\n <!--\n var imgObj = null;\n var animate ;\n\n function init(){\n imgObj = document.getElementById('myImage');\n imgObj.style.position= 'relative';\n imgObj.style.left = '0px';\n }\n\n function moveRight(){\n```\nRollover with a Mouse Event\n\nHere is a simple example showing image rollover with a mouse event.\n\nLet's see what we are using in the following example –\n\n- At the time of loading this page, the ‘if’ statement checks for the existence of the image object. If the image object is unavailable, this block will not be executed.\n- The `Image()` constructor creates and preloads a new image object called `image1`.\n- The `src` property is assigned the name of the external image file called `/images/html.gif`.\n- Similarly, we have created `image2` object and assigned `/images/http.gif` in this object.\n- The # (hash mark) disables the link so that the browser does not try to go to a URL when clicked. This link is an image.\n- The `onMouseOver` event handler is triggered when the user's mouse moves onto the link, and the `onMouseOut` event handler is triggered when the user's mouse moves away from the link (image).\n- When the mouse moves over the image, the HTTP image changes from the first image to the second one. When the mouse is moved away from the image, the original image is displayed.\n- When the mouse is moved away from the link, the initial image html.gif will reappear on the screen.\nThe JavaScript `navigator` object includes a child object called `plugins`. This object is an array, with one entry for each plug-in installed on the browser. The `navigator.plugins` object is supported only by Netscape, Firefox, and Mozilla only.\n\nExample\n\nHere is an example that shows how to list down all the plug-on installed in your browser –\n\n```html\n<html>\n <head>\n <title>List of Plug-Ins</title>\n </head>\n <body>\n <table border=\"1\">\n <tr>\n <th>Plug-in Name</th>\n <th>Filename</th>\n <th>Description</th>\n </tr>\n <script language=\"JavaScript\" type=\"text/javascript\">\n for (i=0; i<navigator.plugins.length; i++) {\n document.write(\"<tr><td>\");\n document.write(navigator.plugins[i].name);\n document.write(\"</td><td>\");\n document.write(navigator.plugins[i].filename);\n }\n </script>\n </table>\n </body>\n</html>\n```\nChecking for Plug-Ins\n\nEach plug-in has an entry in the array. Each entry has the following properties –\n\n- **name** – is the name of the plug-in.\n- **filename** – is the executable file that was loaded to install the plug-in.\n- **description** – is a description of the plug-in, supplied by the developer.\n- **mimeTypes** – is an array with one entry for each MIME type supported by the plug-in.\n\nYou can use these properties in a script to find out the installed plug-ins, and then using JavaScript, you can play appropriate multimedia file. Take a look at the following example.\n\n```html\n<html>\n<head>\n <title>Using Plug-Ins</title>\n</head>\n<body>\n <script language=\"JavaScript\" type=\"text/javascript\">\n media = navigator.mimeTypes[\"video/quicktime\"];\n if (media){\n document.write(\"<embed src='quick.mov' height=100 width=100>\");\n } else {\n document.write(\"<img src='quick.gif' height=100 width=100>\");\n }\n </script>\n</body>\n</html>\n```\nNOTE – Here we are using HTML `<embed>` tag to embed a multimedia file.\n\nControlling Multimedia\n\nLet us take one real example which works in almost all the browsers –\n\n```html\n<html>\n <head>\n <title>Using Embedded Object</title>\n <script type=\"text/javascript\">\n <!--\n function play()\n {\n if (!document.demo.IsPlaying()){\n document.demo.Play();\n }\n }\n function stop()\n {\n if (document.demo.IsPlaying()){\n document.demo.StopPlay();\n }\n }\n function rewind()\n {\n if (document.demo.IsPlaying()){\n document.demo.StopPlay();\n }\n document.demo.Rewind();\n }\n //--> \n </script>\n </head>\n <body>\n <embed src=\"http://www.amrood.com/games/kumite.swf\" width=\"318\" height=\"300\" play=\"false\" loop=\"false\" pluginspage=\"http://www.macromedia.com/go/getflashplayer\" swliveconnect=\"true\">\n <form name=\"form\">\n <input type=\"button\" value=\"Start\" onclick=\"play();\" />\n <input type=\"button\" value=\"Stop\" onclick=\"stop();\" />\n <input type=\"button\" value=\"Rewind\" onclick=\"rewind();\" />\n </form>\n </body>\n</html>\n```\n\nOutput\nEvery now and then, developers commit mistakes while coding. A mistake in a program or a script is referred to as a bug.\n\nThe process of finding and fixing bugs is called debugging and is a normal part of the development process. This section covers tools and techniques that can help you with debugging tasks.\n\n**Error Messages in IE**\n\nThe most basic way to track down errors is by turning on error information in your browser. By default, Internet Explorer shows an error icon in the status bar when an error occurs on the page.\n\nDouble-clicking this icon takes you to a dialog box showing information about the specific error that occurred.\n\nSince this icon is easy to overlook, Internet Explorer gives you the option to automatically show the Error dialog box whenever an error occurs.\n\nTo enable this option, select **Tools → Internet Options → Advanced tab.** and then finally check the \"Display a Notification About Every Script Error\" box option as shown below –\n\n**Error Messages in Firefox or Mozilla**\nOther browsers like Firefox, Netscape, and Mozilla send error messages to a special window called the JavaScript Console or Error Console. To view the console, select Tools → Error Console or Web Development.\n\nUnfortunately, since these browsers give no visual indication when an error occurs, you must keep the Console open and watch for errors as your script executes.\n\n\n\n**Error Notifications**\n\nError notifications that show up on Console or through Internet Explorer dialog boxes are the result of both syntax and runtime errors. These error notification include the line number at which the error occurred.\n\nIf you are using Firefox, then you can click on the error available in the error console to go to the exact line in the script having error.\n\n**How to debug a Script**\n\nThere are various ways to debug your JavaScript –\n\n**Use a JavaScript Validator**\n\nOne way to check your JavaScript code for strange bugs is to run it through a program that checks it to make sure it is valid and that it follows the official syntax rules of the language. These programs are called validating parsers or just validators for short, and often come with commercial HTML and JavaScript editors.\n\nThe most convenient validator for JavaScript is Douglas Crockford's JavaScript Lint, which is available for free at [Douglas Crockford's JavaScript Lint](https://www.crockford.com/javascript/lint.html).\n\nSimply visit that web page, paste your JavaScript (Only JavaScript) code into the text area provided, and click the jslint button. This program will parse through your JavaScript code, ensuring that all the variable and function definitions follow the correct syntax. It will also check JavaScript statements, such as if and while, to ensure they too follow the correct format.\n\n**Add Debugging Code to Your Programs**\n\nYou can use the `alert()` or `document.write()` methods in your program to debug your code. For example, you might write something as follows –\n\n```javascript\nvar debugging = true;\nvar whichImage = \"widget\";\n\nif( debugging )\nalert( \"Calls swapImage() with argument: \" + whichImage );\nvar swapStatus = swapImage( whichImage );\n```\nif( debugging )\n alert( \"Exits swapImage() with swapStatus=\" + swapStatus );\n\nBy examining the content and order of the alert() as they appear, you can examine the health of your program very easily.\n\n**Use a JavaScript Debugger**\n\nA debugger is an application that places all aspects of script execution under the control of the programmer. Debuggers provide fine-grained control over the state of the script through an interface that allows you to examine and set values as well as control the flow of execution.\n\nOnce a script has been loaded into a debugger, it can be run one line at a time or instructed to halt at certain breakpoints. Once execution is halted, the programmer can examine the state of the script and its variables in order to determine if something is amiss. You can also watch variables for changes in their values.\n\nThe latest version of the Mozilla JavaScript Debugger (code-named Venkman) for both Mozilla and Netscape browsers can be downloaded at http://www.hacksrus.com/~ginda/venkman\n\n**Useful tips for developers**\n\nYou can keep the following tips in mind to reduce the number of errors in your scripts and simplify the debugging process –\n\n- Use plenty of **comments**. Comments enable you to explain why you wrote the script the way you did and to explain particularly difficult sections of code.\n\n- Always use **indentation** to make your code easy to read. Indenting statements also makes it easier for you to match up beginning and ending tags, curly braces, and other HTML and script elements.\n\n- Write **modular code**. Whenever possible, group your statements into functions. Functions let you group related statements, and test and reuse portions of code with minimal effort.\n\n- Be consistent in the way you name your variables and functions. Try using names that are long enough to be meaningful and that describe the contents of the variable or the purpose of the function.\n\n- Use consistent syntax when naming variables and functions. In other words, keep them all lowercase or all uppercase; if you prefer Camel-Back notation, use it consistently.\n\n- **Test long scripts** in a modular fashion. In other words, do not try to write the entire script before testing any portion of it. Write a piece and get it to work before adding the next portion of code.\n\n- Use **descriptive variable and function names** and avoid using single-character names.\n\n- **Watch your quotation marks**. Remember that quotation marks are used in pairs around strings and that both quotation marks must be of the same style (either single or double).\n\n- **Watch your equal signs**. You should not used a single = for comparison purpose.\n\n- Declare **variables explicitly** using the var keyword.\n\n**JAVASCRIPT - IMAGE MAP**\n\nYou can use JavaScript to create client-side image map. Client-side image maps are enabled by the usemap attribute for the <img /> tag and defined by special <map> and <area> extension tags.\n\nThe image that is going to form the map is inserted into the page using the <img /> element as normal, except that it carries an extra attribute called usemap. The value of the usemap attribute is the value of the name attribute on the <map> element, which you are about to meet, preceded by a pound or hash sign.\nThe `<map>` element actually creates the map for the image and usually follows directly after the `<img />` element. It acts as a container for the `<area />` elements that actually define the clickable hotspots. The `<map>` element carries only one attribute, the `name` attribute, which is the name that identifies the map. This is how the `<img />` element knows which `<map>` element to use.\n\nThe `<area>` element specifies the shape and the coordinates that define the boundaries of each clickable hotspot.\n\nThe following code combines imagemaps and JavaScript to produce a message in a text box when the mouse is moved over different parts of an image.\n\n```\n<html>\n <head>\n <title>Using JavaScript Image Map</title>\n <script type=\"text/javascript\">\n <!--\n function showTutorial(name){\n document.myform.stage.value = name\n }\n //-->\n </script>\n </head>\n <body>\n <form name=\"myform\">\n <input type=\"text\" name=\"stage\" size=\"20\" />\n </form>\n\n <!-- Create Mappings -->\n <img src=\"/images/usemap.gif\" alt=\"HTML Map\" border=\"0\" usemap=\"#tutorials\"/>\n <map name=\"tutorials\">\n <area shape=\"poly\" coords=\"74,0,113,29,98,72,52,72,38,27\" href=\"/perl/index.htm\" alt=\"Perl Tutorial\" target=\"_self\"\n onMouseOver=\"showTutorial('perl')\"\n onMouseOut=\"showTutorial('')\"/>\n\n <area shape=\"rect\" coords=\"22,83,126,125\" href=\"/html/index.htm\" alt=\"HTML Tutorial\" target=\"_self\"\n onMouseOver=\"showTutorial('html')\"\n onMouseOut=\"showTutorial('')\"/>\n\n <area shape=\"circle\" coords=\"73,168,32\" href=\"/php/index.htm\" alt=\"PHP Tutorial\" target=\"_self\"\n onMouseOver=\"showTutorial('php')\"\n onMouseOut=\"showTutorial('')\"/>\n </map>\n </body>\n</html>\n```\n\n**Output**\n\nYou can feel the map concept by placing the mouse cursor on the image object.\nIt is important to understand the differences between different browsers in order to handle each in the way it is expected. So it is important to know which browser your web page is running in. To get information about the browser your webpage is currently running in, use the built-in `navigator` object.\n\n**Navigator Properties**\n\nThere are several Navigator related properties that you can use in your Web page. The following is a list of the names and descriptions of each.\n\n<table>\n<thead>\n<tr>\n<th>Sr.No</th>\n<th>Property & Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td><code>appCodeName</code></td>\n</tr>\n<tr>\n<td></td>\n<td>This property is a string that contains the code name of the browser, Netscape for Netscape and Microsoft Internet Explorer for Internet Explorer.</td>\n</tr>\n<tr>\n<td>2</td>\n<td><code>appVersion</code></td>\n</tr>\n<tr>\n<td></td>\n<td>This property is a string that contains the version of the browser as well as other useful information such as its language and compatibility.</td>\n</tr>\n<tr>\n<td>3</td>\n<td><code>language</code></td>\n</tr>\n<tr>\n<td></td>\n<td>This property contains the two-letter abbreviation for the language that is used by the browser. Netscape only.</td>\n</tr>\n<tr>\n<td>4</td>\n<td><code>mimTypes[]</code></td>\n</tr>\n<tr>\n<td></td>\n<td>This property is an array that contains all MIME types supported by the client. Netscape only.</td>\n</tr>\n<tr>\n<td>5</td>\n<td><code>platform[]</code></td>\n</tr>\n<tr>\n<td></td>\n<td>This property is a string that contains the platform for which the browser was compiled. "Win32" for 32-bit Windows operating systems</td>\n</tr>\n<tr>\n<td>6</td>\n<td><code>plugins[]</code></td>\n</tr>\n<tr>\n<td></td>\n<td>This property is an array containing all the plug-ins that have been installed on the client. Netscape only.</td>\n</tr>\n</tbody>\n</table>\n**userAgent[]**\n\nThis property is a string that contains the code name and version of the browser. This value is sent to the originating server to identify the client.\n\n**Navigator Methods**\n\nThere are several Navigator-specific methods. Here is a list of their names and descriptions.\n\n<table>\n<thead>\n<tr>\n<th>Sr.No</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>javaEnabled()</td>\n</tr>\n<tr>\n<td></td>\n<td>This method determines if JavaScript is enabled in the client. If JavaScript is enabled, this method returns true; otherwise, it returns false.</td>\n</tr>\n<tr>\n<td>2</td>\n<td>plugings.refresh</td>\n</tr>\n<tr>\n<td></td>\n<td>This method makes newly installed plug-ins available and populates the plugins array with all new plug-in names. Netscape only.</td>\n</tr>\n<tr>\n<td>3</td>\n<td>preference(name,value)</td>\n</tr>\n<tr>\n<td></td>\n<td>This method allows a signed script to get and set some Netscape preferences. If the second parameter is omitted, this method will return the value of the specified preference; otherwise, it sets the value. Netscape only.</td>\n</tr>\n<tr>\n<td>4</td>\n<td>taintEnabled()</td>\n</tr>\n<tr>\n<td></td>\n<td>This method returns true if data tainting is enabled; false otherwise.</td>\n</tr>\n</tbody>\n</table>\n\n**Browser Detection**\n\nThere is a simple JavaScript which can be used to find out the name of a browser and then accordingly an HTML page can be served to the user.\n\n```html\n<html>\n <head>\n <title>Browser Detection Example</title>\n </head>\n <body>\n <script type=\"text/javascript\">\n<!--\n var userAgent = navigator.userAgent;\n var opera = (userAgent.indexOf('Opera') !== -1);\n var ie = (userAgent.indexOf('MSIE') !== -1);\n var gecko = (userAgent.indexOf('Gecko') !== -1);\n var netscape = (userAgent.indexOf('Mozilla') !== -1);\n var version = navigator.appVersion;\n if (opera){\n```\ndocument.write(\"Opera based browser\");\n// Keep your opera specific URL here.\n}\nelse if (gecko){\ndocument.write(\"Mozilla based browser\");\n// Keep your gecko specific URL here.\n}\nelse if (ie){\ndocument.write(\"IE based browser\");\n// Keep your IE specific URL here.\n}\nelse if (netscape){\ndocument.write(\"Netscape based browser\");\n// Keep your Netscape specific URL here.\n}\nelse{\ndocument.write(\"Unknown browser\");\n// You can include version to along with any above condition.\ndocument.write(\"<br /> Browser version info : \" + version);\n//-->\n</script>\n</body>\n</html>\n\nOutput"}}},{"rowIdx":77,"cells":{"id":{"kind":"string","value":"59c8052f539ebc780c5563e6894ce232a4003d0e"},"text":{"kind":"string","value":"Package ‘sem’\n\nMay 19, 2020\n\nVersion 3.1-11\nDate 2020-05-16\nTitle Structural Equation Models\nDepends R (>= 3.5.0), stats\nImports matrixcalc, MASS, boot, mi (>= 0.9-99), utils\nSuggests polycor, DiagrammeR\nLazyLoad yes\nLazyData yes\nByteCompile yes\nDescription Functions for fitting general linear structural\nequation models (with observed and latent variables) using the RAM approach,\nand for fitting structural equations in observed-variable models by two-stage least squares.\nLicense GPL (>= 2)\nAuthor John Fox [aut, cre],\nZhenghua Nie [aut],\nJarrett Byrnes [aut],\nMichael Culbertson [ctb],\nSaikat DebRoy [ctb],\nMichael Friendly [ctb],\nBenjamin Goodrich [ctb],\nRichard H. Jones [ctb],\nAdam Kramer [ctb],\nGeorges Monette [ctb],\nR-Core [ctb]\nMaintainer John Fox <jfox@mcmaster.ca>\nRepository CRAN\nRepository/R-Forge/Project sem\nRepository/R-Forge/Revision 178\nRepository/R-Forge/DateTimeStamp 2020-05-16 22:57:51\nDate/Publication 2020-05-19 13:20:02 UTC\nNeedsCompilation yes\nBollen's Data on Industrialization and Political Democracy\n\nDescription\n\nThis data set includes four measures of democracy at two points in time, 1960 and 1965, and three measures of industrialization in 1960, for 75 developing countries.\n\nUsage\n\nBollen\nFormat\n\nA data frame with 75 observations on the following 11 variables.\n\n\\[\n\\begin{align*}\n&y_1 \\text{ freedom of the press, 1960} \\\\\n&y_2 \\text{ freedom of political opposition, 1960} \\\\\n&y_3 \\text{ fairness of elections, 1960} \\\\\n&y_4 \\text{ effectiveness of elected legislature, 1960} \\\\\n&y_5 \\text{ freedom of the press, 1965} \\\\\n&y_6 \\text{ freedom of political opposition, 1965} \\\\\n&y_7 \\text{ fairness of elections, 1965} \\\\\n&y_8 \\text{ effectiveness of elected legislature, 1965} \\\\\n&x_1 \\text{ GNP per capita, 1960} \\\\\n&x_2 \\text{ energy consumption per capita, 1960} \\\\\n&x_3 \\text{ percentage of labor force in industry, 1960}\n\\end{align*}\n\\]\n\nDetails\n\nVariables $y_1$ through $y_4$ are intended to be indicators of the latent variable *political democracy in 1960*; $y_5$ through $y_8$ indicators of *political democracy in 1965*; and $x_1$ through $x_3$ indicators of *industrialization in 1960*.\n\nSource\n\npersonal communication from Ken Bollen.\n\nReferences\n\n\n---\n\n**bootSem**\n\n*Bootstrap a Structural Equation Model*\n\n**Description**\n\nBootstraps a structural equation model in an *sem* object (as returned by the *sem* function).\nUsage\n\nbootSem(model, ...)\n\n## S3 method for class 'sem'\nbootSem(model, R=100, Cov=cov, data=model$data,\n max.failures=10, show.progress=TRUE, ...)\n\n## S3 method for class 'msem'\nbootSem(model, R=100, Cov=cov, data=model$data,\n max.failures=10, show.progress=TRUE, ...)\n\n## S3 method for class 'bootsem'\nprint(x, digits=getOption(\"digits\"), ...)\n\n## S3 method for class 'bootsem'\nsummary(object,\n type=c(\"perc\", \"bca\", \"norm\", \"basic\", \"none\"), level=0.95, ...)\n\nArguments\n\nmodel an sem or msem object, produced by the sem function.\nR the number of bootstrap replications; the default is 100, which should be enough for computing standard errors, but not confidence intervals (except for the normal-theory intervals).\nCov a function to compute the input covariance or moment matrix; the default is cov. Use cor if the model is fit to the correlation matrix. The function hetcor in the polycor package will compute product-moment, polychoric, and polyserial correlations among mixed continuous and ordinal variables (see the first example below for an illustration).\ndata in the case of a sem (i.e., single-group) model, a data set in a form suitable for Cov; for example, for the default Cov=cov, data may be a numeric data frame or a numeric matrix. In the case of an msem (i.e., multi-group) model, a list of data sets (again in the appropriate form), one for each group; in this case, bootstrapping is done within each group, treating the groups as strata. Note that the original observations are required, not just the covariance matrix of the observed variables in the model. The default is the data set stored in the sem object, which will be present only if the model was fit to a data set rather than to a covariance or moment matrix, and may not be in a form suitable for Cov.\nmax.failures maximum number of consecutive convergence failures before bootSem gives up.\nshow.progress display a text progress bar on the console tracing the bootstrap replications.\nx, object an object of class bootsem.\ndigits controls the number of digits to print.\ntype type of bootstrapped confidence intervals to compute; the default is \"perc\" (percentile); see boot.ci for details.\nlevel level for confidence intervals; default is 0.95.\n... in bootSem, arguments to be passed to sem; otherwise ignored.\n**Details**\n\n`bootSem` implements the nonparametric bootstrap, assuming an independent random sample. Convergence failures in the bootstrap resamples are discarded (and a warning printed); more than `max.failures` consecutive convergence failures (default, 10) result in an error. You can use the `boot` function in the `boot` package for more complex sampling schemes and additional options.\n\nBootstrapping is implemented by resampling the observations in `data`, recalculating the input covariance matrix with `Cov`, and refitting the model with `sem`, using the parameter estimates from the original sample as start-values.\n\n**Warning:** the bootstrapping process can be very time-consuming.\n\n**Value**\n\n`bootSem` returns an object of class `bootsem`, which inherits from class `boot`, supported by the `boot` package. The returned object contains the following components:\n\n- t0: the estimated parameters in the model fit to the original data set.\n- t: a matrix containing the bootstrapped estimates, one bootstrap replication per row.\n- data: the data to which the model was fit.\n- seed: the value of `.Random.seed` when `bootSem` was called.\n- statistic: the function used to produce the bootstrap replications; this is always the local function `refit` from `bootSem`.\n- sim: always set to \"ordinary\"; see the documentation for the `boot` function.\n- stype: always set to \"i\"; see the documentation for the `boot` function.\n- call: the call of the `bootSem` function.\n- weights: a vector of length equal to the number of observations `N`, with entries `1/N`. For a multi-group model, the weights in group `j` are `1/N_j`, the inverse of the number of observations in the group.\n- strata: a vector of length `N` containing the number of the stratum to which each observation belongs; for a single-group model, all entries are 1.\n\n**Author(s)**\n\nJohn Fox <jfox@mcmaster.ca>\n\n**References**\n\n\n**See Also**\n\n`boot`, `sem`\nExamples\n\n# A simple confirmatory factor-analysis model using polychoric correlations.\n# The polycor package is required for the hetcor function.\nif (require(polycor)){\n\n# The following function returns correlations computed by hetcor,\n# and is used for the bootstrapping.\n\nhcor <- function(data) hetcor(data, std.err=FALSE)$correlations\n\nmodel.cnes <- specifyModel(text=\"\nF -> MBSA2, lam1\nF -> MBSA7, lam2\nF -> MBSA8, lam3\nF -> MBSA9, lam4\nF <-> F, NA, 1\nMBSA2 <-> MBSA2, the1\nMBSA7 <-> MBSA7, the2\nMBSA8 <-> MBSA8, the3\nMBSA9 <-> MBSA9, the4\n\")\n\nR.cnes <- hcor(CNES)\n\nsem.cnes <- sem(model.cnes, R.cnes, N=1529)\nsummary(sem.cnes)\n}\n# Note: this can take a minute:\nset.seed(12345) # for reproducibility\n\nsystem.time(boot.cnes <- bootSem(sem.cnes, R=100, Cov=hcor, data=CNES))\nsummary(boot.cnes, type=\"norm\")\n# cf., standard errors to those computed by summary(sem.cnes)\n\n## Not run: # because of long execution time\n\n# An example bootstrapping a multi-group model\n\nmod.hs <- cfa(text=\"\nspatial: visual, cubes, paper, flags\nverbal: general, paragrap, sentence, wordc, wordm\nmemory: wordr, numberr, figurer, object, numberf, figurew\nmath: deduct, numeric, problemr, series, arithmet\n\")\n\nmod.mg <- multigroupModel(mod.hs, groups=c(\"Female\", \"Male\"))\nsem.mg <- sem(mod.mg, data=HS.data, group=\"Gender\",\n formula = ~ visual + cubes + paper + flags +\n general + paragrap + sentence + wordc + wordm +\n wordr + numberp + figurer + object + numberf + figurew +\n deduct + numeric + problemr + series + arithmet\n)\n\n# Note: this example can take several minutes or more;\n# you can decrease R if you just want to see how it works:\n\nset.seed(12345) # for reproducibility\n\nsystem.time(boot.mg <- bootSem(sem.mg, R=100))\nsummary(boot.mg, type=\"norm\")\n# cf., standard errors to those computed by summary(sem.mg)\n\n## End(Not run)\n\n---\n\n**CNES**\n\n**Variables from the 1997 Canadian National Election Study**\n\n**Description**\n\nThese variables are from the mailback questionnaire to the 1997 Canadian National Election Study, and are intended to tap attitude towards “traditional values.”\n\n**Usage**\n\nCNES\n\n**Format**\n\nA data frame with 1529 observations on the following 4 variables.\n\n- **MBSA2** an ordered factor with levels StronglyDisagree, Disagree, Agree, and StronglyAgree, in response to the statement, “We should be more tolerant of people who choose to live according to their own standards, even if they are very different from our own.”\n\n- **MBSA7** an ordered factor with levels StronglyDisagree, Disagree, Agree, and StronglyAgree, in response to the statement, “Newer lifestyles are contributing to the breakdown of our society.”\n\n- **MBSA8** an ordered factor with levels StronglyDisagree, Disagree, Agree, and StronglyAgree, in response to the statement, “The world is always changing and we should adapt our view of moral behaviour to these changes.”\n\n- **MBSA9** an ordered factor with levels StronglyDisagree, Disagree, Agree, and StronglyAgree, in response to the statement, “This country would have many fewer problems if there were more emphasis on traditional family values.”\neffects.sem\n\nTotal, Direct, and Indirect Effects for Structural Equation Models\n\nDescription\n\nThe sem method for the standard generic function effects computes total, direct, and indirect effects for a fitted structural equation model according to the method described in Fox (1980).\n\nUsage\n\n```r\n## S3 method for class 'sem'\neffects(object, ...) # S3 method for class 'msem'\neffects(object, ...) # S3 method for class 'semeffects'\nprint(x, digits = getOption(\"digits\"), ...)\n# S3 method for class 'semeffectsList'\nprint(x, digits = getOption(\"digits\"), ...)\n```\n\nArguments\n\n- `object` a fitted structural-equation model object produced by the `sem` function.\n- `x` an object of class `semeffects` or `semeffectsList`, produced by `effects`.\n- `digits` digits to print.\n- `...` not used.\n\nValue\n\n`effect.sem` returns an object of class `semeffects` with Total, Direct, and Indirect elements.\n\nAuthor(s)\n\nJohn Fox <jfox@mcmaster.ca>\n\nReferences\n\n\nSee Also\n\n- `sem`\nExamples\n\n```r\n## Not run:\n\n# These examples are from Fox (1980)\n\n# In the first pair of examples, readMoments() and specifyModel() read from the\n# input stream. These examples cannot be executed via example() but can be entered\n# at the command prompt. The Blau and Duncan example is repeated using file input;\n# this example can be executed via example().\n\n# The recursive Blau and Duncan basic stratification model:\n# x1 is father's education, x2 father's SES, y3 respondent's education,\n# y4 SES of respondent's first job, y5 respondent's SES in 1962\n\nR.bd <- readMoments(names=c(\"x1\", \"x2\", \"y3\", \"y4\", \"y5\"))\n\nmod.bd <- specifyModel()\n\ny3 <- x1, gam31\ny3 <- x2, gam32\ny4 <- x2, gam42\ny4 <- y3, beta43\ny5 <- x2, gam52\ny5 <- y3, beta53\ny5 <- y4, beta54\n\nsem.bd <- sem(mod.bd, R.bd, N=20700, fixed.x=c(\"x1\", \"x2\"))\n\nsummary(sem.bd)\neffects(sem.bd)\n\n# The nonrecursive Duncan, Haller, and Portes peer-influences model for observed variables:\n\nR.DHP <- readMoments(diag=FALSE, names=c(\"ROccAsp\", \"REDasp\", \"FOccAsp\",\n\"FedAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FIQ\", \"FParAsp\"))\n\nmodel.dhp <- specifyModel()\n\nRIQ -> ROccAsp, gam51, NA\nRSES -> ROccAsp, gam52, NA\n```\n**fscores**\n\n*Factor Scores for Latent Variables*\n\n**Description**\n\nCalculate factor scores or factor-score coefficients for the latent variables in a structural-equation model.\n\n**Usage**\n\n```r\n## S3 method for class 'sem'\nfscores(model, data=model$data, center=TRUE, scale=FALSE, ...)\n## S3 method for class 'msem'\nfscores(model, data=model$data, center=TRUE, scale=FALSE, ...)\n```\nArguments\n\nmodel \nan object of class \"sem\" or \"msem\", produced by the \\texttt{sem} function.\n\ndata \nan optional numeric data frame or matrix containing the observed variables in \nthe model; if not \\texttt{NULL}, the estimated factor scores are returned; if \\texttt{NULL}, the \nfactor-score \\textit{coefficients} are returned. The default is the data element of \\texttt{model}, \nwhich is non-\\texttt{NULL} if the model was fit to a data set rather than a covariance or \nmoment matrix.\n\ncenter \nif \\texttt{TRUE}, the default, the means of the observed variables are subtracted prior \nto computing factor scores. One would normally use this option if the model is \nestimated from a covariance or correlation matrix among the observed variables.\n\nscale \nif \\texttt{TRUE}, the possibly centered variables are divided by their root-mean-squares; \nthe default is \\texttt{FALSE}. One would normally use this option if the model is esti-\nmated from a correlation matrix among the observed variables. Centering and \nscaling are performed by the \\texttt{scale} function.\n\n... \narguments to pass down.\n\nDetails\n\nFactor-score coefficients are computed by the “regression” method as \\( B = C^{-1}C^* \\), where \\( C \\) is the \nmodel-implied covariance or moment matrix among the observed variables and \\( C^* \\) is the matrix of \nmodel-implied covariances or moments between the observed and latent variables.\n\nValue\n\nEither a matrix of estimated factor scores (if the \\texttt{data} argument is supplied) or a matrix of factor-\nscore coefficients (otherwise). In the case of an \"msem\" argument, a list of matrices is returned.\n\nAuthor(s)\n\nJohn Fox \\texttt{<jfox@mcmaster.ca>}\n\nReferences\n\n\nSee Also\n\n\\texttt{sem}, \\texttt{scale}\n\nExamples\n\n# In the first example, \\texttt{readMoments()} and \\texttt{specifyModel()} read from the \n# input stream. This example cannot be executed via \\texttt{example()} but can be entered \n# at the command prompt. The example is repeated using file input; \n# this example can be executed via \\texttt{example()}. \n## Not run: \n\nS.wh <- \\texttt{readMoments(names=c(\\textquotesingle Anomia67\\textquotesingle ,\\textquotesingle Powerless67\\textquotesingle ,\\textquotesingle Anomia71\\textquotesingle ,...}}\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nmodel.wh.1 <- specifyModel()\nHS.data\n\nDescription\n\nThis data set, for scores on a variety of tests, was originally in the MBESS package. A new version of the data set in that package doesn’t appear to be identical to this one.\n\nUsage\n\nHS.data\n\nFormat\n\nA data frame with 301 observations on the following 32 variables.\n\nid a numeric vector\nGender a factor with levels Female Male\ngrade a numeric vector\nagey a numeric vector\nagem a numeric vector\nschool a factor with levels Grant-White Pasteur\nvisual a numeric vector\ncubes a numeric vector\npaper a numeric vector\nflags a numeric vector\ngeneral a numeric vector\nparagrap a numeric vector\nsentence a numeric vector\nwordc a numeric vector\nwordm a numeric vector\naddition a numeric vector\ncode a numeric vector\ncounting a numeric vector\nstraight a numeric vector\nwordr a numeric vector\nnumberr a numeric vector\nfigurer a numeric vector\nobject a numeric vector\nnumberf a numeric vector\nfigurew a numeric vector\ndeduct a numeric vector\nnumeric a numeric vector\nproblemr a numeric vector\nseries a numeric vector\narithmet a numeric vector\npaperrev a numeric vector\nflagssub a numeric vector\nSource\n\nOriginally from Holzinger and Swineford (1939). This copy is originally from version 4.6.0 of the MBESS package.\n\nReferences\n\n\nExamples\n\nsummary(HS.data)\n\ninformation.critera Additional Information Criteria\n\nDescription\n\nThese are generic functions for computing, respectively, the AICc (second-order corrected Akaike Information Criterion) and CAIC (consistent Akaike Information Criterion).\n\nUsage\n\nAICc(object, ...)\n\nCAIC(object, ...)\n\nArguments\n\nobject an object for which an appropriate AICc or CAIC method exists.\n\n... possible additional arguments for methods.\n\nAuthor(s)\n\nJarrett Byrnes and John Fox <jfox@mcmaster.ca>\n\nReferences\n\n\nSee Also\n\nAICc.objectiveML, CAIC.objectiveML\nKlein’s Data on the U. S. Economy\n\nDescription\nData for Klein’s (1950) simple econometric model of the U. S. economy.\nThe Klein data frame has 22 rows and 10 columns.\n\nUsage\nKlein\n\nFormat\nThis data frame contains the following columns:\n\n- **Year** 1921–1941\n- **C** consumption.\n- **P** private profits.\n- **Wp** private wages.\n- **I** investment.\n- **K.lag** capital stock, lagged one year.\n- **X** equilibrium demand.\n- **Wg** government wages.\n- **G** government non-wage spending.\n- **T** indirect business taxes and net exports.\n\nSource\n\nReferences\n\nExamples\n```r\nKlein$P.lag <- c(NA, Klein$P[-22])\nKlein$X.lag <- c(NA, Klein$X[-22])\n\nsummary(tsls(C ~ P + P.lag + I(Wp + Wg),\n instruments=~1 + G + T + Wg + I(Year - 1931) + K.lag + P.lag + X.lag,\n data=Klein))\n\nsummary(tsls(I ~ P + P.lag + K.lag,\n instruments=~1 + G + T + Wg + I(Year - 1931) + K.lag + P.lag + X.lag,\n data=Klein))\n```\ndata=Klein))\n\nsummary tsls(Wp ~ X + X.lag + I(Year - 1931),\n instruments=I + G + T + Wg + I(Year - 1931) + K.lag + P.lag + X.lag,\n data=Klein))\n\n---\n\nKmenta\n\nPartly Artificial Data on the U. S. Economy\n\nDescription\n\nThese are partly contrived data from Kmenta (1986), constructed to illustrate estimation of a simultaneous-equation model.\n\nThe Kmenta data frame has 20 rows and 5 columns.\n\nUsage\n\nKmenta\n\nFormat\n\nThis data frame contains the following columns:\n\nQ food consumption per capita.\nP ratio of food prices to general consumer prices.\nD disposable income in constant dollars.\nF ratio of preceding year’s prices received by farmers to general consumer prices.\nA time in years.\n\nDetails\n\nThe exogenous variables D, F, and A are based on real data; the endogenous variables P and Q were generated by simulation.\n\nSource\n\nmiSem uses the mi function in the mi package to generate multiple imputations of missing data, fitting the specified model to each completed data set.\n\nUsage\n\nmiSem(model, ...)\n\n## S3 method for class 'semmod'\nmiSem(model, ..., data, formula = ~., raw=FALSE,\n fixed.x=NULL, objective=objectiveML,\n n.imp=5, n.chains=n.imp, n.iter=30, seed=sample(1e6, 1), mi.args=list(),\n show.progress=TRUE)\n\n## S3 method for class 'semmodList'\nmiSem(model, ..., data, formula = ~., group, raw=FALSE,\n fixed.x=NULL, objective=msemObjectiveML,\n n.imp=5, n.chains=n.imp, n.iter=30, seed=sample(1e6, 1), mi.args=list(),\n show.progress=TRUE)\n\n## S3 method for class 'miSem'\nprint(x, ...)\n\n## S3 method for class 'miSem'\nsummary(object, digits=max(3, getOption(\"digits\") - 2), ...)\n\nArguments\n\nmodel an SEM model-description object of class semmod or semmodList, created by\n specifyEquations cfa, or specifyModel, in the case of a multi-group model\n in combination with multigroupModel.\n\n..., formula, raw, fixed.x, objective, group\n arguments to be passed to sem.\n\ndata an R data frame, presumably with some missing data (encoded as NA), containing\n the data for fitting the SEM, possibly along with other variables to use to obtain\n multiple imputations of missing values. In the case of a multi-group model, this\n must be a single data frame.\n\nn.imp number of imputations (default 5).\n\nn.chains number of Markov chains (default is the number of imputations).\n\nn.iter number of iterations for the multiple-imputation process (default 30).\n\nseed seed for the random-number generator (default is an integer sampled from 1 to\n 1E6); stored in the resulting object.\nmiSem\n\nmi.args other arguments to be passed to mi.\n\nshow.progress show a text progress bar on the console tracking model fitting to the multiple imputations; this is distinct from the progress of the multiple-imputation process, which is controlled by the verbose argument to mi (and which, although it defaults to TRUE, fails to produce verbose output on Windows system, as of mi version 1.0).\n\nx, object an object of class \"miSem\".\n\ndigits for printing numbers.\n\nValue\n\nmiSem returns an object of class \"miSem\" with the following components:\n\ninitial.fit an sem model object produced using objectiveFIML if raw=TRUE, or the objective function given by the objective argument otherwise.\n\nmi.fits a list of sem model objects, one for each imputed data set.\n\nimputation the object produced by complete, containing the completed imputed data sets.\n\nseed the seed used for the random number generator.\n\nmi.data the object returned by mi, containing the multiple imputations, and useful, e.g., for diagnostic checking of the imputation process.\n\nAuthor(s)\n\nJohn Fox <jfox@mcmaster.ca>\n\nReferences\n\n\nSee Also\n\nsem, mi\n\nExamples\n\nmod.cfa.tests <- cfa(raw=TRUE, text=\"\nverbal: x1, x2, x3\nmath: y1, y2, y3\n\")\nimps <- miSem(mod.cfa.tests, data=Tests, fixed.x=\"Intercept\",\nraw=TRUE, seed=12345)\nsummary(imps, digits=3)\n\n# introduce some missing data to the HS.data data set:\nHS <- HS.data[, c(2,7:10,11:15,20:25,26:30)]\nset.seed(12345)\n```r\nr <- sample(301, 100, replace=TRUE)\nc <- sample(2:21, 100, replace=TRUE)\nfor (i in 1:100) HS[r[i], c[i]] <- NA\n\nmod.hs <- cfa(text=\nspatial: visual, cubes, paper, flags\nverbal: general, paragrap, sentence, wordc, wordm\nmemory: wordr, numberr, figurer, object, numberf, figurew\nmath: deduct, numeric, problemr, series, arithmet\n\")\n\nmod.mg <- multigroupModel(mod.hs, groups=c(\"Female\", \"Male\"))\n\nsystem.time( # relatively time-consuming!\n imps.mg <- miSem(mod.mg, data=HS, group=\"Gender\", seed=12345)\n)\n\nsummary(imps.mg, digits=3)\n```\n\n---\n\n### Methods for sem Objects Fit Using the `objectiveML`, `objectiveGLS`, `objectiveFIML`, `msemlObjectiveML`, and `msemlObjectiveGLS Objective Functions`\n\n#### Description\n\nThese functions are for objects fit by `sem` using the `objectiveML` (multivariate-normal full-information maximum-likelihood), `link(objectiveFIML)` (multivariate-normal full-information maximum-likelihood in the presence of missing data), `objectiveGLS` (generalized least squares), and `msemlObjectiveML` (multigroup multivariate-normal FIML) objective functions.\n\n#### Usage\n\n```r\n## S3 method for class 'objectiveML'\nanova(object, model.2, robust=FALSE, ...)\n## S3 method for class 'objectiveFIML'\nanova(object, model.2, ...)\n\n## S3 method for class 'objectiveML'\nlogLik(object, ...)\n## S3 method for class 'objectiveFIML'\nlogLik(object, saturated=FALSE,\n intercept=\"Intercept\", iterlim=1000, ...)\n## S3 method for class 'objectiveML'\ndeviance(object, ...)\n## S3 method for class 'objectiveFIML'\ndeviance(object, saturated.logLik, ...)\n## S3 method for class 'msemlObjectiveML'\ndeviance(object, ...)\n```\n## S3 method for class 'objectiveML'\nAIC(object, ..., k)\n## S3 method for class 'objectiveFIML'\nAIC(object, saturated.logLik, ..., k)\n## S3 method for class 'msemObjectiveML'\nAIC(object, ..., k)\n## S3 method for class 'objectiveML'\nAICc(object, ...)\n## S3 method for class 'objectiveFIML'\nAICc(object, saturated.logLik, ...)\n## S3 method for class 'msemObjectiveML'\nAICc(object, ...)\n## S3 method for class 'objectiveML'\nBIC(object, ...)\n## S3 method for class 'objectiveFIML'\nBIC(object, saturated.logLik, ...)\n## S3 method for class 'msemObjectiveML'\nBIC(object, ...)\n## S3 method for class 'objectiveML'\nCAIC(object, ...)\n## S3 method for class 'objectiveFIML'\nCAIC(object, saturated.logLik, ...)\n## S3 method for class 'msemObjectiveML'\nCAIC(object, ...)\n## S3 method for class 'objectiveML'\nprint(x, ...)\n## S3 method for class 'objectiveGLS'\nprint(x, ...)\n## S3 method for class 'objectiveFIML'\nprint(x, saturated=FALSE, ...)\n## S3 method for class 'msemObjectiveML'\nprint(x, ...)\n## S3 method for class 'msemObjectiveGLS'\nprint(x, ...)\n## S3 method for class 'objectiveML'\nsummary(object, digits=getOption(\"digits\"),\n conf.level=.90, robust=FALSE, analytic.se=object$t <= 500,\n fit.indices=c(\"GFI\", \"AGFI\", \"RMSEA\", \"NFI\", \"NNFI\", \"CFI\", \"RNI\",\n \"IFI\", \"SRMR\", \"AIC\", \"AICc\", \"BIC\", \"CAIC\"), ...)\n## S3 method for class 'objectiveFIML'\nsummary(object, digits=getOption(\"digits\"), conf.level=.90,\n fit.indices=c(\"AIC\", \"AICc\", \"BIC\", \"CAIC\"),\n saturated=FALSE, intercept=\"Intercept\", saturated.logLik, ...)\n## S3 method for class 'objectiveGLS'\nsummary(object, digits=getOption(\"digits\"), conf.level=.90,\n fit.indices=c(\"GFI\", \"AGFI\", \"RMSEA\", \"NFI\", \"NNFI\", \"CFI\", \"RNI\", \"IFI\", \"SRMR\"),\n ...)\n## S3 method for class 'msemObjectiveML'\nsummary(object, digits=getOption(\"digits\"),\n conf.level=.90, robust=FALSE,\n analytic.se=object$t <= 500,\n fit.indices=c(\"GFI\", \"AGFI\", \"RMSEA\", \"NFI\", \"NNFI\", \"CFI\", \"RNI\",\n \"IFI\", \"SRMR\", \"AIC\", \"AICc\", \"BIC\"), ...)\n\n## S3 method for class 'msemObjectiveGLS'\nsummary(object, digits=getOption(\"digits\"),\n conf.level=.90,\n fit.indices=c(\"GFI\", \"AGFI\", \"RMSEA\", \"NFI\", \"NNFI\",\n \"CFI\", \"RNI\", \"IFI\", \"SRMR\"), ...)\n\n### Arguments\n\n- **object, model.2, x**\n - an object inheriting from class objectiveML, objectiveGLS, objectiveFIML, msemObjectiveML, or msemObjectiveGLS.\n- **robust**\n - if TRUE, compute robust standard errors or test.\n- **fit.indices**\n - a character vector of “fit indices” to report; the allowable values are those given in Usage above, and vary by the objective function. If the argument isn’t given then the fit indices reported are taken from the R fit.indices option; if this option isn’t set, then only the AIC and BIC are reported for models fit with objectiveML, objectiveFIML, or msemObjectiveML, and no fit indices are reported for models fit with objectiveGLS or msemObjectiveGLS.\n- **k, ...**\n - ignored.\n- **digits**\n - digits to be printed.\n- **conf.level**\n - level for confidence interval for the RMSEA index (default is .9).\n- **analytic.se**\n - use analytic (as opposed to numeric) coefficient standard errors; default is TRUE where analytic standard errors are available if there are no more than 100 parameters in the model and FALSE otherwise.\n- **saturated**\n - if TRUE (the default is FALSE); compute the log-likelihood (and statistics that depend on it) for the saturated model when the objective function is FIML in the presence of missing data. This can be computationally costly.\n- **intercept**\n - the name of the intercept regressor in the raw data, to be used in calculating the saturated log-likelihood for the FIML estimator; the default is “Intercept”.\n- **saturated.logLik**\n - the log-likelihood for the saturated model, as returned by logLik with saturated=TRUE; if absent, this will be computed and the computation can be time-consuming.\n- **iterlim**\n - iteration limit used by the nlm optimizer to compute the saturated log-likelihood for the FIML estimator with missing data; defaults to 1000.\n\n### Author(s)\n\nJohn Fox <jfox@mcmaster.ca> and Jarrett Byrnes\n\n### References\n\nSee sem.\nSee Also\n\n`sem`, `objective.functions`, `modIndices.objectiveML`\n\n---\n\n`modIndices` Modification Indices for Structural Equation Models\n\nDescription\n\n`mod.indices` calculates modification indices (score tests) and estimated parameter changes for the fixed and constrained parameters in a structural equation model fit by multinormal maximum likelihood.\n\nUsage\n\n```r\n## S3 method for class 'objectiveML'\nmodIndices(model, duplicated, deviance=NULL, ...)\n```\n\n```r\n## S3 method for class 'msemObjectiveML'\nmodIndices(model, ...)\n```\n\n```r\n## S3 method for class 'modIndices'\nprint(x, n.largest=5, ...)\n```\n\n```r\n## S3 method for class 'msemModIndices'\nprint(x, ...)\n```\n\n```r\n## S3 method for class 'modIndices'\nsummary(object, round=2, print.matrices=c(\"both\", \"par.change\", \"mod.indices\"), ...)\n```\n\n```r\n## S3 method for class 'msemModIndices'\nsummary(object, ...)\n```\n\nArguments\n\n- `model`: an object of class `objectiveML` or `msemObjectiveML`, produced by the `sem` function.\n- `object, x`: an object of class `modIndices` or `msemModIndices`, produced by the `modIndices` function.\n- `n.largest`: number of modification indices to print in each of the $A$ and $P$ matrices of the RAM model.\n- `round`: number of places to the right of the decimal point in printing modification indices.\n- `print.matrices`: which matrices to print: estimated changes in the fixed parameters, modification indices, or both (the default).\n- `duplicated, deviance`: for internal use.\n- `...`: arguments to be passed down.\nDetails\n\nModification indices are one-df chi-square score (\"Lagrange-multiplier\") test statistics for the fixed and constrained parameters in a structural equation model. They may be regarded as an estimate of the improvement in the likelihood-ratio chi-square statistic for the model if the corresponding parameter is respecified as a free parameter. The \\texttt{modIndices} function also estimates the change in the value of a fixed or constrained parameter if the parameter is respecified as free. When several parameters are set equal, modification indices and estimated changes are given for all but the first. Modification indices and estimated parameter changes for currently free parameters are given as \\texttt{NA}.\n\nThe method employed is described in Saris, Satorra, and Sorbom (1987) and Sorbom (1989).\n\nValue\n\n\\texttt{modIndices} returns an object of class \\texttt{modIndices} with the following elements:\n\n- \\texttt{mod.A} modification indices for the elements of the \\texttt{A} matrix.\n- \\texttt{mod.P} modification indices for the elements of the \\texttt{P} matrix.\n- \\texttt{par.A} estimated parameter changes for the elements of the \\texttt{A} matrix.\n- \\texttt{par.P} estimated parameter changes for the elements of the \\texttt{P} matrix.\n\nAuthor(s)\n\nJohn Fox \\texttt{<jfox@mcmaster.ca>} and Michael Culbertson\n\nReferences\n\n\nSee Also\n\n\\texttt{sem}\n\nExamples\n\n# In the first example, \\texttt{readMoments()} and \\texttt{specifyModel()} read from the # input stream. This example cannot be executed via \\texttt{example()} but can be entered # at the command prompt. The example is repeated using file input;\n# this example can be executed via \\texttt{example()}.\n## Not run:\n# This example is adapted from the SAS manual\nS.wh <- \\texttt{readMoments(names=c('Anomia67','Powerless67','Anomia71',\n 'Powerless71','Education','SEI'))}\n\n 11.834\n 6.947 9.364\n 6.819 5.091 12.532\n 4.783 5.028 7.495 9.986\nmodel.wh <- specifyModel()\nAlienation67 -> Anomia67, NA, 1\nAlienation67 -> Powerless67, NA, 0.833\nAlienation71 -> Anomia71, NA, 1\nAlienation71 -> Powerless71, NA, 0.833\nSES -> Education, NA, 1\nSES -> SEI, lamb, NA\nSES -> Alienation67, gam1, NA\nAlienation67 -> Alienation71, beta, NA\nSES -> Alienation71, gam2, NA\nAnomia67 <-> Anomia67, the1, NA\nAnomia71 <-> Anomia71, the1, NA\nPowerless67 <-> Powerless67, the2, NA\nPowerless71 <-> Powerless71, the2, NA\nEducation <-> Education, the3, NA\nSEI <-> SEI, the4, NA\nAnomia67 <-> Anomia71, the5, NA\nPowerless67 <-> Powerless71, the5, NA\nAlienation67 <-> Alienation67, psi1, NA\nAlienation67 <-> Alienation71, psi2, NA\nSES <-> SES, phi, NA\n\nobjective.functions\n\nsem Objective-Function Builders\n\nDescription\n\nThese functions return objective functions suitable for use with optimizers called by sem. The user would not normally call these functions directly, but rather supply one of them in the objective argument to sem. Users may also write their own objective functions. objectiveML and objectiveML2 are for multinormal maximum-likelihood estimation; objectiveGLS and objectiveGLS2 are for\ngeneralized least squares; and objectiveFIML is for so-called “full-information maximum-likelihood” estimation in the presence of missing data. The FIML estimator provides the same estimates as the ML estimator when there is no missing data; it can be slow because it iterates over the unique patterns of missing data that occur in the data set. objectiveML and objectiveGLS use compiled code and are therefore substantially faster. objectiveML2 and objectiveGLS2 are provided primarily to illustrate how to write sem objective functions in R. msemObjectiveML uses compiled code for fitting multi-group models by multinormal maximum likelihood; msemObjectiveML2 is similar but doesn’t use compiled code. msemObjectiveGLS uses compiled code and is for fitting multi-group models by generalized least squares.\n\nUsage\n\nobjectiveML(gradient=TRUE, hessian=FALSE)\nobjectiveML2(gradient=TRUE)\n\nobjectiveGLS(gradient=FALSE)\nobjectiveGLS2(gradient=FALSE)\n\nobjectiveFIML(gradient=TRUE, hessian=FALSE)\nobjectiveFIML2(gradient=TRUE, hessian=FALSE)\n\nmsemObjectiveML(gradient=TRUE)\nmsemObjectiveML2(gradient=TRUE)\nmsemObjectiveGLS(gradient=FALSE)\n\nArguments\n\ngradient If TRUE, the object that’s returned includes a function for computing an analytic gradient; there is at present no analytic gradient available for objectiveFIML, objectiveGLS, objectiveGLS2, or msemObjectiveGL.\n\nhessian If TRUE, the object returned includes a function to compute an analytic Hessian; only available for objectiveML and not generally recommended.\n\nValue\n\nThese functions return an object of class \"semObjective\", with up to two elements:\n\nobjective an objective function.\n\ngradient a gradient function.\n\nAuthor(s)\n\nJohn Fox <jfox@mcmaster.ca>\n\nReferences\n\nSee sem.\noptimizers\n\nSee Also\n\nsem, optimizers\n\noptimizers \n\nsem Optimizers\n\nDescription\n\nThe default optimizer used by sem is optimizerSem, which employs compiled code and is integrated with the objectiveML and objectiveGLS objective functions; optimizerSem, written by Zhenghua Nie, is a modified version of the standard R nlm optimizer, which was written by Saikat DebRoy, R-core, and Richard H. Jones. The other functions call optimizers (nlm, optim, or nlminb), to fit structural equation models, and are called by the sem function. The user would not normally call these functions directly, but rather supply one of them in the optimizer argument to sem. Users may also write them own optimizer functions. msemOptimizerNlm is for fitting multigroup models, and also adapts the nlm code.\n\nUsage\n\noptimizerSem(start, objective=objectiveML, gradient=TRUE, maxiter, debug, par.size, model.description, warn, ...)\n\noptimizerMsem(start, objective=msemObjectiveML, gradient=TRUE, maxiter, debug, par.size, model.description, warn=FALSE, ...)\n\noptimizerNlm(start, objective=objectiveML, gradient=TRUE, maxiter, debug, par.size, model.description, warn, ...)\n\noptimizerOptim(start, objective=objectiveML, gradient=TRUE, maxiter, debug, par.size, model.description, warn, method=\"CG\", ...)\n\noptimizerNlminb(start, objective=objectiveML, gradient=TRUE, maxiter, debug, par.size, model.description, warn, ...)\n\nmsemOptimizerNlm(start, objective=msemObjectiveML, gradient=TRUE, maxiter, debug, par.size, model.description, warn=FALSE, ...)\n\nArguments\n\n<table>\n<thead>\n<tr>\n<th>Argument</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>start</td>\n<td>a vector of start values for the parameters.</td>\n</tr>\n<tr>\n<td>objective</td>\n<td>the objective function to be optimized; see objective.functions.</td>\n</tr>\n<tr>\n<td>gradient</td>\n<td>TRUE if an analytic gradient is to be used (if one is available).</td>\n</tr>\n<tr>\n<td>maxiter</td>\n<td>the maximum number of iterations allowed.</td>\n</tr>\n<tr>\n<td>debug</td>\n<td>TRUE to show the iteration history and other available information about the optimization.</td>\n</tr>\n</tbody>\n</table>\npar.size \"startvalues\" to have the optimizer scale the problem according to the magnitudes of the start values (ignored by optimizerNlminb).\n\nmodel.description a list with elements describing the structural-equation model (see the code for details).\n\nwarn if FALSE, suppress warnings during the optimization.\n\nmethod the method to be employed by the optim optimizer; the default is \"CG\" (conjugate-gradient).\n\n... additional arguments for the nlm, optim, or nlminb optimizer.\n\nValue\n\nAn object of class \"semResult\", with elements:\n\nconvergence TRUE if the optimization apparently converged.\niterations the number of iterations required.\npar the vector of parameter estimates.\nvcov the estimated covariance matrix of the parameter estimates, based on a numeric Hessian; not supplied by optimizerNlminb.\ncriterion the optimized value of the objective function.\nC the model-implied covariance or moment matrix at the parameter estimates.\nA the estimated $A$ matrix.\nP the estimated $P$ matrix.\n\nAuthor(s)\n\nJohn Fox <jfox@mcmaster.ca>, and Zhenghua Nie, in part adapting work by Saikat DebRoy, R-core, and Richard H. Jones.\n\nSee Also\n\nsem, objective.functions, nlm, optim, nlminb\n\n---\n\n**pathDiagram** \n*Draw Path Diagram*\n\n---\n\n**Description**\n\npathDiagram creates a description of the path diagram for a structural-equation-model or SEM-specification object to be processed by the graph-drawing program *dot*. \nUsage\n\npathDiagram(model, ...) \n\n## S3 method for class 'sem'\n\npathDiagram(model, file = \"pathDiagram\", \n style = c(\"ram\", \"traditional\"), \n output.type = c(\"html\", \"graphics\", \"dot\"), graphics.fmt = \"pdf\", \n dot.options = NULL, \n size = c(8, 8), node.font = c(\"Helvetica\", 14), \n edge.font = c(\"Helvetica\", 10), digits = 2, \n rank.direction = c(\"LR\", \"TB\"), \n min.rank = NULL, max.rank = NULL, same.rank = NULL, \n variables = model$var.names, var.labels, parameters, par.labels, \n ignore.double = TRUE, ignore.self = FALSE, error.nodes = TRUE, \n edge.labels = c(\"names\", \"values\", \"both\"), \n edge.colors = c(\"black\", \"black\"), \n edge.weight = c(\"fixed\", \"proportional\"), \n node.colors = c(\"transparent\", \"transparent\", \"transparent\"), \n standardize = FALSE, ...) \n\n## S3 method for class 'semmod'\n\npathDiagram(model, obs.variables, ...) \n\nmath(text, html.only=FALSE, hat=FALSE)\n\nArguments\n\nmodel\n\na structural-equation-model or SEM-specification object produced by sem, or, respectively, specifyEquations, specifyModel, or cfa.\n\n... \n\narguments passed down, e.g., from the semmod method to the sem method.\n\nfile\n\na file name, by default \"pathDiagram\", given without an extension, to which to write the dot description of the path diagram if output.type \"html\" or \"graphics\" is selected, and for the graphics output file (with appropriate extension) if \"graphics\" output is selected, in which case a \"dot\" file and a graphics file of type specified by the graphics.fmt argument (below); file may include a path specification.\n\nstyle\n\n\"ram\" (the default) for a RAM path diagram including self-directed double-headed arrows representing variances, including error variances; or \"traditional\" for a path diagram including nodes representing error variables.\n\noutput.type\n\nif \"html\" (the default), the path diagram will open in the user’s default web browser; if \"dot\", a file containing dot commands will be written; if \"graphics\", both dot and graphics files will be written.\n\ngraphics.fmt\n\nda graphics format recognized by the dot program; the default is \"pdf\"; graphics.fmt is also used for the extension of the graphics file that is created.\n\ndot.options\n\noptions to be passed to the dot program, given as a character string.\n\nsize\n\nthe size of the graph, in inches.\nnode.font | font name and point-size for printing variable names.\nedge.font | font name and point-size for printing arrow names or values.\ndigits | number of digits after the decimal point (default, 2) to which to round parameter estimates.\nrank.direction | draw graph left-to-right, \"LR\", the default, or top-to-bottom, \"TB\".\nmin.rank | a character string listing names of variables to be assigned minimum rank (order) in the graph; the names should be separated by commas.\nmax.rank | a character string listing names of variables to be assigned maximum rank in the graph; the names should be separated by commas.\nsame.rank | a character string or vector of character strings of variables to be assigned equivalent rank in the graph; names in each string should be separated by commas.\nvariables | variable names; defaults to the variable names in model. If specified, the variable names should be in the same order as in model.\nvar.labels | a character vector with labels to be used in lieu of (some of) the variables names, for greater flexibility in labelling nodes in the graph — e.g., the labels can be created with the math function. The elements of the vector must have names corresponding to variables in the model.\nparameters | parameter names; defaults to the parameter names in model. If specified, the parameter names should be in the same order as in model.\npar.labels | a character vector with labels to be used in lieu of (some of) the parameter names, for greater flexibility in labelling edges in the graph — e.g., the labels can be created with the math function. The elements of the vector must have names corresponding to parameters in the model.\nignore.double | if TRUE, the default, double-headed arrows, representing variances and covariances, are not graphed.\nignore.self | if TRUE (the default is FALSE), and ignore.double=FALSE, self-directed double-headed arrows representing error variances are suppressed; note that if ignore.double=TRUE, all double-headed arrows, including self-directed arrows, are suppressed.\nerror.nodes | if TRUE (the default) and style=\"traditional\", show the nodes representing error variables.\nedge.labels | \"names\" to label arrows with parameter names; \"values\" to label arrows with parameter estimates, or \"both\".\nedge.colors | two-element character vector giving colors of positive and negative arrows respectively; the default is c(\"black\",\"black\").\nedge.weight | if \"proportional\" (the default is \"fixed\"), the thickness of edges is proportional to the absolute size of the corresponding parameter estimate; this is generally sensible only if standardize=TRUE.\nnode.colors | a two- or three-element character vector giving colors of nodes representing exogenous, endogenous, and error variables (for traditional path diagrams) consecutively; the default is \"transparent\" for all three; if a two colors are given, error variables are colored as exogenous (the first color).\nstandardize | if TRUE, display standardized coefficients; default is FALSE.\nobs.variables | a character vector with the names of the observed variables in the model.\ntext\n\nA character string or vector of character strings to be translated into node or edge label symbols. If a vector of character strings is supplied, then the elements of the vector should be named with the corresponding variable (node) or parameter (edge) name.\n\nhtml.only\n\nIf TRUE (the default is FALSE), the character strings in text are to be treated as an HTML character codes, in which case the prefix \"#\" and suffix \";\" are appended to each. Otherwise, text should only contain the names of lowercase or uppercase Greek letters, such as \"alpha\" or \"Alpha\". The full set of Greek letters recognized is given in the file Greek.txt in the package's etc subdirectory – or type sem:::Greek at the R command prompt. In either case, the symbols may be followed by numeric subscripts in curly braces consisting of numerals (e.g., \"beta_{12}\"), and/or numeric superscripts (e.g., \"sigma^{2}\", \"sigma_{1}^{2}\"). Depending upon your OS, subscripts and superscripts may only work properly with HTML output from pathDiagram, not with graphics output produced by dot.\n\nhat\n\nIf TRUE (the default is FALSE), a hat (circumflex) is placed over the symbols in text; this feature doesn't produce a visually appealing result.\n\nDetails\n\nPathDiagram creates a description of the path diagram for a structural-equation-model or SEM-specification object to be processed by the graph-drawing program dot, which can be called automatically; see Koutsofios and North (2002) and http://www.graphviz.org/. To obtain graphics output directly, the dot program must be on the system search path.\n\nAlternatively, HTML output can be created in a web browser without an independent installation of dot using facilities in the DiagrammeR package.\n\nThe math function can be used to create node (variable) and edge (arrow) labels with symbols such as Greek letters, subscripts, and superscripts.\n\nThe semmod method of pathDiagram sets up a call to the sem method.\n\nThe various arguments to pathDiagram can be used to customize the diagram, but if there are too many constraints on node placement, dot may fail to produce a graph or may produce a distorted graph. pathDiagram can create both RAM-style diagrams, in which variances are represented as self-directed arrows, and traditional path diagrams, in which error variables appear explicitly as nodes. As is conventional, latent variables (including error variables) are represented as ellipses and observed variables as rectangles; double-headed arrows represent covariances (and in RAM diagrams, variances) and single-headed arrows represent structural coefficients.\n\nValue\n\nPathDiagram invisibly returns a character vector containing dot commands. math returns a character vector containing suitable HTML markup.\n\nAuthor(s)\n\nJohn Fox <jfox@mcmaster.ca>, Adam Kramer, and Michael Friendly\nReferences\n\nSee Also\nsem, specifyEquations, specifyModel, cfa\n\nExamples\n\nif (interactive()) {\n # The Duncan, Haller, and Portes Peer-Influences Model\n\n R.DHP <- readMoments(diag=FALSE,\n names=c(\"ROccAsp\", \"REdAsp\", \"FOccAsp\",\n \"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"),\n text=\"\n .6247 .3269 .3669\n .4216 .3275 .6404\n .2137 .2742 .1124 .0839\n .4105 .4043 .2903 .2598 .1839\n .3240 .4047 .3054 .2786 .0489 .2220\n .2930 .2407 .4105 .3054 .0186 .1861 .2707\n .2995 .2863 .5191 .5007 .0782 .3355 .2382 .2950\n .0760 .0702 .2784 .1988 .1147 .1021 .0931 -.0438 .2087\")\n\n model.dhp <- specifyModel(text=\"\n RParAsp -> RGenAsp, gam11, NA\n RIQ -> RGenAsp, gam12, NA\n RSES -> RGenAsp, gam13, NA\n FSES -> RGenAsp, gam14, NA\n RSES -> FGenAsp, gam23, NA\n FSES -> FGenAsp, gam24, NA\n FIQ -> FGenAsp, gam25, NA\n FParAsp -> FGenAsp, gam26, NA\n FGenAsp -> RGenAsp, beta12, NA\n RGenAsp -> FGenAsp, beta21, NA\n RGenAsp -> R0ccAsp, NA, 1\n RGenAsp -> REdAsp, lam21, NA\n FGenAsp -> FOccAsp, NA, 1\n FGenAsp -> FEdAsp, lam42, NA\n RGenAsp <-> RGenAsp, ps11, NA\n FGenAsp <-> FGenAsp, ps22, NA\n RGenAsp <-> FGenAsp, ps12, NA\n R0ccAsp <-> R0ccAsp, theta1, NA\n REdAsp <-> REdAsp, theta2, NA\n FOccAsp <-> FOccAsp, theta3, NA\n FEdAsp <-> FEdAsp, theta4, NA\n\"\n\n sem.dhp <- sem(model.dhp, R.DHP, 329,\n fixed.x=c(\"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"))\n}\npathDiagram(sem.dhp, min.rank=\"RIQ, RSES, RParAsp, FParAsp, FSES, FIQ\",\nmax.rank=\"ROccAsp, REdAsp, FEdAsp, FOccAsp\",\nsame.rank=\"RGenAsp, FGenAsp\",\nedge.labels=\"values\")\n\npathDiagram(model.dhp,\nobs.variables=c(\"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\",\n \"FParAsp\", \"ROccAsp\", \"REdAsp\", \"FOccAsp\", \"FEdAsp\"),\nstyle=\"traditional\",\nnode.colors=c(\"pink\", \"lightblue\", \"lightgreen\"),\nmin.rank=\"RIQ, RSES, RParAsp, FParAsp, FSES, FIQ\",\nmax.rank=\"ROccAsp, REdAsp, FEdAsp, FOccAsp\",\nsame.rank=\"RGenAsp, FGenAsp\",\nvar.labels=c(RParAsp=\"Respondent Parental Aspiration\",\n RIQ=\"Respondent IQ\",\n RSES=\"Respondent SES\",\n FSES=\"Friend SES\",\n FIQ=\"Friend IQ\",\n FParAsp=\"Friend Parental Aspiration\",\n ROccAsp=\"Respondent Occupational Aspiration\",\n REDasp=\"Respondent Educational Aspiration\",\n RGenAsp=\"Respondent General Aspiration\",\n FOccAsp=\"Friend Occupational Aspiration\",\n FEdAsp=\"Friend Educational Aspiration\",\n FGenAsp=\"Friend General Aspiration\",\n math(c(RGenAsp.error=\"xi_{1}\",\n FGenAsp.error=\"xi_{2}\",\n ROccAsp.error=\"epsilon_{1}\",\n REDasp.error=\"epsilon_{2}\",\n FOccAsp.error=\"epsilon_{3}\",\n FEdAsp.error=\"epsilon_{4}\")),\npar.labels=math(c(gam11=\"gamma_{11}\",\n gam12=\"gamma_{12}\",\n gam13=\"gamma_{13}\",\n gam14=\"gamma_{14}\",\n gam23=\"gamma_{23}\",\n gam24=\"gamma_{24}\",\n gam25=\"gamma_{25}\",\n gam26=\"gamma_{26}\",\n beta12=\"beta_{12}\",\n beta21=\"beta_{21}\",\n lam21=\"lambda_{21}\"\n\nlambda21=\"lambda_{21}\"))\")\n\n# the following example contributed by Michael Friendly:\nunion <- readMoments(diag=TRUE, names=c('y1', 'y2', 'y3', 'x1', 'x2'), text=\"\n14.610\n-5.250 11.017\n-8.057 11.087 31.971\n-18.857 17.861 28.250 7.139 215.662\n\"\n)\n\nunion.mod <- specifyEquations(covs=c(\"x1\", \"x2\"), text=\"\ny1 = gam12*x2\ny2 = beta21*y1 + gam22*x2\ny3 = beta31*y1 + beta32*y2 + gam31*x1\n\"\n)\n\nunion.sem <- sem(union.mod, union, N=173)\n\ndot <- pathDiagram(union.sem, style=\"traditional\", ignore.double=FALSE, error.nodes=FALSE, edge.labels=\"values\", min.rank=c(\"Years\", \"Age\"), max.rank=c(\"Sentiment\", \"Sentiment.error\"), same.rank=c(\"Deference, Deference.error\", \"Activism, Activism.error\"), variables=c(\"Deference\", \"Activism\", \"Sentiment\", \"Years\", \"Age\"), edge.colors=c(\"black\", \"red\"), node.colors = c(\"pink\", \"lightblue\"))\n\ncat(paste(dot, collapse=\"\\n\")) # dot commands\n\n---\n\n**ram**\n\nRAM Matrix for a Structural-Equation Model\n\n**Description**\n\nPrint the labelled RAM definition matrix for a structural-equation model fit by `sem`.\n\n**Usage**\n\n```r\nram(object, digits=getOption(\"digits\"), startvalues=FALSE)\n```\n\n**Arguments**\n\n- **object**: an object of class `sem` returned by the `sem` function.\n- **digits**: number of digits for printed output.\n- **startvalues**: if `TRUE`, start values for parameters are printed; otherwise, the parameter estimates are printed; the default is `FALSE`. \nValue\nA data frame containing the labelled RAM definition matrix, which is normally just printed.\n\nAuthor(s)\nJohn Fox <jfox@mcmaster.ca>\n\nSee Also\nsem\n\nExamples\n\n# ------------ assumes that Duncan, Haller and Portes peer-influences model\n# ----------------------- has been fit and is in sem.dhp\n\n### Not run:\nram(sem.dhp)\n\n### End(Not run)\nArguments\n\n- **object**: a one-sided model formula or an object coercible to a numeric matrix.\n- **formula**: a one-sided model formula specifying the model matrix for which raw moments are to be computed; note that a constant is included if it is not explicitly suppressed by putting \\(-1\\) in the formula.\n- **data**: an optional data frame containing the variables in the formula. By default the variables are taken from the environment from which `rawMoments` is called.\n- **subset**: an optional vector specifying a subset of observations to be used in computing moments.\n- **na.action**: a function that indicates what should happen when the data contain NAs. The default is set by the `na.action` option.\n- **contrasts**: an optional list. See the `contrasts.arg` argument of `model.matrix.default`.\n- **na.rm**: if TRUE, any data rows with missing data will be removed.\n- **cov**: a covariance or correlation matrix.\n- **mean**: a vector of means.\n- **N**: the number of observations on which the covariances or correlations are based.\n- **sd**: an optional vector of standard deviations, to be given if `cov` is a correlation matrix.\n- **x**: an object of class `rawmoments` to print.\n- **...**: arguments passed down.\n\nValue\n\n`rawMoments` and `cov2raw` return an object of class `rawmoments`, which is simply a matrix with an attribute \"N\" that contains the number of observations on which the moments are based.\n\nAuthor(s)\n\nJohn Fox <jfox@mcmaster.ca>\n\nSee Also\n\n- `sem`\n\nExamples\n\n# the following are all equivalent (with the exception of the name of the intercept):\n\n```r\nrawMoments(cbind(1, Kmenta))\nrawMoments(~ Q + P + D + F + A, data=Kmenta)\nCov <- with(Kmenta, cov(cbind(Q, P, D, F, A)))\ncov2raw(Cov, colMeans(Kmenta), nrow(Kmenta))\n```\nInput a Covariance, Correlation, or Raw Moment Matrix\n\nDescription\n\nThis function makes it simpler to input covariance, correlation, and raw-moment matrices to be analyzed by the `sem` function. The matrix is input in lower-triangular form on as many lines as is convenient, omitting the above-diagonal elements. The elements on the diagonal may also optionally be omitted, in which case they are taken to be 1.\n\nUsage\n\n```r\nreadMoments(file = \"\", text, diag = TRUE,\n names = as.character(paste(\"X\", 1:n, sep = \"\")))\n```\n\nArguments\n\n- **file** The (quoted) file from which to read the moment matrix, including the path to the file if it is not in the current directory. If \"\" (the default) and the text argument is absent, then the moment matrix is read from the standard input stream, and is terminated by a blank line.\n- **text** The moment matrix given as a character string, as an alternative to specifying the file argument or reading the moments from the input stream — e.g., when the session is not interactive and there is no standard input.\n- **diag** If TRUE (the default), then the input matrix includes diagonal elements.\n- **names** a character vector containing the names of the variables, to label the rows and columns of the moment matrix.\n\nValue\n\nReturns a lower-triangular matrix (i.e., with zeroes above the main diagonal) suitable for input to `sem`.\n\nAuthor(s)\n\nJohn Fox <jfox@mcmaster.ca>\n\nSee Also\n\n- `sem`\nExamples\n\n```r\nR.DHP <- readMoments(diag=FALSE, names=c(\"ROccAsp\", \"REdAsp\", \"FOccAsp\", \n \"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"),\n text=\"\n\")\n```\n\nR.DHP\n\n# the following will work only in an interactive sessions:\n```r\n## Not run:\nR.DHP <- readMoments(diag=FALSE, names=c(\"ROccAsp\", \"REdAsp\", \"FOccAsp\", \n \"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"))\n```\n\nR.DHP\n\n## End(Not run)\n\n---\n\nresiduals.sem \n\nResidual Covariances for a Structural Equation Model\n\nDescription\n\nThese functions compute residual covariances, variance-standardized residual covariances, and normalized residual covariances for the observed variables in a structural-equation model fit by sem.\n\nUsage\n\n```r\n## S3 method for class 'sem'\nresiduals(object, ...)\n## S3 method for class 'msem'\nresiduals(object, ...)\n```\n## S3 method for class 'sem'\nstandardizedResiduals(object, ...)\n## S3 method for class 'msem'\nstandardizedResiduals(object, ...)\n\n## S3 method for class 'objectiveML'\nnormalizedResiduals(object, ...)\n## S3 method for class 'objectiveGLS'\nnormalizedResiduals(object, ...)\n## S3 method for class 'mserrorgiveObjectiveML'\nnormalizedResiduals(object, ...)\n\n### Arguments\n\n- **object**: an object inheriting from class `sem` or `msem` returned by the `sem` function.\n- **...**: not for the user.\n\n### Details\n\nResiduals are defined as $S - C$, where $S$ is the sample covariance matrix of the observed variables and $C$ is the model-reproduced covariance matrix. The *standardized* residual covariance for a pair of variables divides the residual covariance by the product of the sample standard deviations of the two variables, $(s_{ij} - c_{ij})/(s_{ii}s_{jj})^{1/2}$. The *normalized* residual is given by\n\n$$\n\\frac{s_{ij} - c_{ij}}{[(c_{ii}c_{jj} - c_{ij}^2)/N^*]^{1/2}}\n$$\n\nwhere $N^*$ is the number of observations minus one if the model is fit to a covariance matrix, or the number of observations if it is fit to a raw moment matrix.\n\n### Value\n\nEach function returns a matrix of residuals.\n\n### Author(s)\n\nJohn Fox <jfox@mcmaster.ca>\n\n### References\n\n\n### See Also\n\n`sem`\nExamples\n\n# In the first example, readMoments() and specifyModel() read from the # input stream. This example cannot be executed via example() but can be entered # at the command prompt. The example is repeated using file input; # this example can be executed via example().\n## Not run:\n# Duncan, Haller, and Portes peer-influences model\n\n```r\nR.DHP <- readMoments(diag=FALSE, names=c(\"ROccAsp\", \"REdAsp\", \"FOccAsp\", \"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"))\n```\n\n```r\n.6247\n.3269 .3669\n.4216 .3275 .6404\n.2137 .2742 .1124 .0839\n.4105 .4043 .2903 .2598 .1839\n.3240 .4047 .3054 .2786 .0489 .2220\n.2930 .2407 .4105 .3607 .0186 .1861 .2707\n.2995 .5191 .5007 .0782 .3355 .2302 .2950\n.0760 .0702 .2784 .1988 .1147 .1021 .0931 -.0438 .2087\n```\n\n```r\nmodel.dhp <- specifyModel()\nRParAsp -> RGenAsp, gam11, NA\nRIQ -> RGenAsp, gam12, NA\nRSES -> RGenAsp, gam13, NA\nFSES -> RGenAsp, gam14, NA\nRSES -> FGenAsp, gam23, NA\nFSES -> FGenAsp, gam24, NA\nFIQ -> FGenAsp, gam25, NA\nFParAsp -> FGenAsp, gam26, NA\nFGenAsp -> RGenAsp, beta12, NA\nRGenAsp -> FGenAsp, beta21, NA\nRGenAsp -> ROccAsp, NA, 1\nRGenAsp -> REdAsp, lam21, NA\nFGenAsp -> FOccAsp, NA, 1\nFGenAsp -> FEdAsp, lam42, NA\nRGenAsp <-> RGenAsp, ps11, NA\nFGenAsp <-> FGenAsp, ps22, NA\nRGenAsp <-> FGenAsp, ps12, NA\nROccAsp <-> ROccAsp, theta1, NA\nREdAsp <-> REdAsp, theta2, NA\nFOccAsp <-> FOccAsp, theta3, NA\nFEdAsp <-> FEdAsp, theta4, NA\n```\n\n```r\nsem.dhp <- sem(model.dhp, R.DHP, 329,\n fixed.x=c(\"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"))\n```\n\n```r\nresiduals(sem.dhp)\nnormalizedResiduals(sem.dhp)\nstandardizedResiduals(sem.dhp) # same as residuals because model is fit to correlations\n```\n## End(Not run)\n# The following example can be executed via example():\netc <- system.file(package=\"sem\", \"etc\") # path to data and model files\n\n(R.DHP <- readMoments(file=file.path(etc, \"R-DHP.txt\"),\ndiag=FALSE, names=c(\"ROccAsp\", \"REdAsp\", \"FOccAsp\",\n\"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\")))\n\n(model.dhp <- specifyModel(file=file.path(etc, \"model-DHP.txt\")))\n\n(sem.dhp <- sem(model.dhp, R.DHP, 329,\n fixed.x=c(\"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\")))\n\nresiduals(sem.dhp)\n\nnormalizedResiduals(sem.dhp)\n\nstandardizedResiduals(sem.dhp) # same as residuals because model is fit to correlations\n\n---\n\n**sem**\n\n*General Structural Equation Models*\n\n**Description**\n\n`sem` fits general structural equation models (with both observed and unobserved variables). Observed variables are also called *indicators* or *manifest variables*; unobserved variables are also called *factors* or *latent variables*. Normally, the generic function (`sem`) is called directly with a `semmod` first argument produced by `specifyModel`, `specifyEquations`, or `cfa`, invoking the `sem.semmod` method, which in turn sets up a call to the `sem.default` method; thus, the user may wish to specify arguments accepted by the `semmod` and `default` methods. Similarly, for a multi-group model, `sem` would normally be called with a `semmodList` object produced by `multigroupModel` as its first argument, and would then generate a call to the code `msemmod` method.\n\n**Usage**\n\n```r\n## S3 method for class 'semmod'\nsem(model, S, N, data,\n raw=identical(na.action, na.pass), obs.variables=rownames(S),\n fixed.x=NULL, formula= ~ ., na.action=na.omit,\n robust=!missing(data), debug=FALSE,\n optimizer=optimizerSem, objective=objectiveML, \n\n## Default S3 method:\nsem(model, S, N, raw=FALSE, data=NULL, start.fn=startvalues,\n pattern.number=NULL, valid.data.patterns=NULL,\n use.means=TRUE, param.names,\n var.names, fixed.x=NULL, robust=!is.null(data), semmod=NULL, debug=FALSE,\n analytic.gradient=!identical(objective, objectiveFIML),\n warn=FALSE, maxiter=1000, par.size=c(\"ones\", \"startvalues\"),\n start.tol=1E-6, optimizer=optimizerSem, objective=objectiveML, cls, \n\n## S3 method for class 'semmodList'\n```\n\n---\n\n**sem**\n\n*General Structural Equation Models*\n\n**Description**\n\n`sem` fits general structural equation models (with both observed and unobserved variables). Observed variables are also called *indicators* or *manifest variables*; unobserved variables are also called *factors* or *latent variables*. Normally, the generic function (`sem`) is called directly with a `semmod` first argument produced by `specifyModel`, `specifyEquations`, or `cfa`, invoking the `sem.semmod` method, which in turn sets up a call to the `sem.default` method; thus, the user may wish to specify arguments accepted by the `semmod` and `default` methods. Similarly, for a multi-group model, `sem` would normally be called with a `semmodList` object produced by `multigroupModel` as its first argument, and would then generate a call to the code `msemmod` method.\n\n**Usage**\n\n```r\n## S3 method for class 'semmod'\nsem(model, S, N, data,\n raw=identical(na.action, na.pass), obs.variables=rownames(S),\n fixed.x=NULL, formula= ~ ., na.action=na.omit,\n robust=!missing(data), debug=FALSE,\n optimizer=optimizerSem, objective=objectiveML, \n\n## Default S3 method:\nsem(model, S, N, raw=FALSE, data=NULL, start.fn=startvalues,\n pattern.number=NULL, valid.data.patterns=NULL,\n use.means=TRUE, param.names,\n var.names, fixed.x=NULL, robust=!is.null(data), semmod=NULL, debug=FALSE,\n analytic.gradient=!identical(objective, objectiveFIML),\n warn=FALSE, maxiter=1000, par.size=c(\"ones\", \"startvalues\"),\n start.tol=1E-6, optimizer=optimizerSem, objective=objectiveML, cls, \n\n## S3 method for class 'semmodList'\n```\nArguments\n\nmodel\nRAM specification, which is a simple encoding of the path diagram for the model. The model may be given either in symbolic form (as a semmod object, as returned by the specifyModel, specifyEquations, or cfa function, or as a character matrix), invoking sem.semmod, which calls sem.default after setting up the model, or (less conveniently) in numeric form, invoking sem.default directly, which is not recommended (see Details below). The model argument may also be a multigroup-model specification, as produced by multigroupModel.\n\nS\ncovariance matrix among observed variables; may be input as a symmetric matrix, or as a lower- or upper-triangular matrix. S may also be a raw (i.e., “uncorrected”) moment matrix — that is, a sum-of-squares-and-products matrix divided by N. This form of input is useful for fitting models with intercepts, in which case the moment matrix should include the mean square and cross-products for a unit variable all of whose entries are 1; of course, the raw mean square for the unit variable is 1. Raw-moment matrices may be computed by rawMoments. If the ram argument is given in symbolic form, then the observed-variable covariance or raw-moment matrix may contain variables that do not appear in the model, in which case a warning is printed. S may also be a list\nof covariance or moment matrices for each group in a multigroup model. As an alternative to specifying $S$, the user may supply a data frame containing the data for the model (see the argument data).\n\n$N$ \nnumber of observations on which the covariance matrix is based; for a multigroup model, a vector of group $N$s.\n\ndata \nAs a generally preferable alternative to specifying $S$ and $N$, the user may supply a data frame containing the data to which the model is to be fit. In a multigroup model, the data argument may be a list of data frames or a single data frame; in the later event, the factor given as the group argument is used to split the data into groups.\n\nstart.fn \na function to compute startvalues for the free parameters of the model; two functions are supplied, startvalues and a older version, startvalues2, the first of which is the default.\n\nna.action \na function to process missing data, if raw data are supplied in the data argument. The default is na.omit, which returns only complete cases; specify na.action=na.pass to get FIML estimates in the presence of missing data from the objectiveFIML and objectiveFIML2 objective functions.\n\nraw \nTRUE if $S$ is a raw moment matrix or if a raw moment matrix — as opposed to a covariance matrix — is to be computed from data; the default is FALSE unless the na.action argument is set to na.pass.\n\npattern.number, valid.data.patterns \nthese arguments pass information about valid (i.e., non-missing) data patterns and normally would not be specified directly by the user.\n\nuse.means \nWhen raw data are supplied and intercepts are included in the model, use the observed-variable means as start values for the intercepts; the default is TRUE.\n\nobs.variables \nnames of observed variables, by default taken from the row names of the covariance or moment matrix $S$, which may be given directly or generated according to the data and formula arguments.\n\nfixed.x \nnames (if the ram matrix is given in symbolic form) or indices (if it is in numeric form) of fixed exogenous variables. Specifying these obviates the necessity of having to fix the variances and covariances among these variables (and produces correct degrees of freedom for the model chisquare).\n\nformula \na one-sided formula, to be applied to data to generate the variables for which covariances or raw moments are computed. The default formula is $\\sim$, i.e., all of the variables in the data, including an implied intercept; if a covariance matrix is to be computed, the constant is suppressed. In a multigroup model, alternatively a list one one-sided formulas as be given, to be applied individually to the groups.\n\nrobust \nIn sem: if TRUE, then quantities are calculated that can be used to compute robust estimates of coefficient standard errors and robust tests when the model is fit by multinormal maximum likelihood; the default is TRUE when the data argument is TRUE, and this option is only available when the data argument is given. In vcov: if TRUE, return a robust coefficient covariance matrix (if object contains the requisite information).\n\nsemmod \na semmod object containing the description of the model; optional, and normally supplied not directly by the user but via the semmod method for sem.\ndebug\n\nif TRUE, some information is printed to help you debug the symbolic model specification; for example, if a variable name is misspelled, sem will assume that the variable is a (new) latent variable. Information about the optimization will also be printed, but details will vary with the optimizer employed. The default is FALSE.\n\n... arguments to be passed down, including from sem.default to the optimizer.\n\nparam.names\n\nnames of the $t$ free parameters, given in their numerical order; default names are Param1, ..., Param. Note: Should not be specified when the model is given in symbolic form.\n\nvar.names\n\nnames of the $m$ entries of the $v$ vector (typically the observed and latent variables — see below), given in their numerical order; default names are Var1, ..., Varm. Note: Should not be specified when the model is given in symbolic form.\n\nanalytic.gradient\n\nif TRUE (the default, except for the objectiveFIML objective function, where, at present, an analytic gradient slows down the computation), then analytic first derivatives are used in the maximization of the likelihood if the optimizer employed will accept them; otherwise numeric derivatives are used, again if the optimizer will compute them.\n\nwarn\n\nif TRUE, warnings produced by the optimization function will be printed. This should generally not be necessary, since sem prints its own warning, and saves information about convergence. The default is FALSE.\n\nmaxiter\n\nthe maximum number of iterations for the optimization of the objective function, to be passed to the optimizer.\n\npar.size\n\nthe anticipated size of the free parameters; if \"ones\", a vector of ones is used; if \"startvalues\", taken from the start values. You can try changing this argument if you encounter convergence problems. The default is \"startvalues\" if the largest input variance is at least 100 times the smallest, and \"ones\" otherwise. Whether this argument is actually used depends upon the optimizer employed.\n\nstart.tol, tol\n\nif the magnitude of an automatic start value is less than start.tol, then it is set to start.tol; defaults to 1E-6.\n\noptimizer\n\na function to be used to minimize the objective function; the default for single-group models is optimizerSem. Alternatives are nlm, which employs the standard R optimizer nlm; optimizerOptim, which employs optim; and optimizerNlminb, which uses nlminb — or the user can supply an optimizer. For multigroup model, the default is optimizerMsem, and msemOptimizerNlminb, based on nlm, is provided as an alternative.\n\nobjective\n\nAn objective function to be minimized, sometimes called a “fit” function in the SEM literature. The default for single-group models is objectiveML, which produces maximum-likelihood estimates assuming multinormality. An alternative is objectiveGLS, which produced generalized least squares estimates — or the user can supply an objective function to be minimized. For multigroup models, the default is available is msemObjectiveML for ML estimates and an alternative is msemObjectiveGLS for GLS estimates.\n\ncls\n\nprimary class to be assigned to the result; normally this is not specified directly, but rather is inferred from the objective function.\nThe model is set up using either RAM (\"reticular action model\" – don’t ask!) notation – a simple format for specifying general structural equation models by coding the “arrows” in the path diagram for the model (see, e.g., McArdle and McDonald, 1984) – typically using the `specifyModel` function; in equation format using the `specifyEquations` function; or, for a simple confirmatory factor analysis model, via the `cfa` function. In any case, the model is represented internally in RAM format.\n\nThe variables in the \\( v \\) vector in the model (typically, the observed and unobserved variables, but not error variables) are numbered from 1 to \\( m \\). the RAM matrix contains one row for each (free or constrained) parameter of the model, and may be specified either in symbolic format or in numeric format.\n\nA symbolic ram matrix consists of three columns, as follows:\n\n1. **Arrow specification:** This is a simple formula, of the form \"A -> B\" or, equivalently, \"B <-A\" for a regression coefficient (i.e., a single-headed or directional arrow); \"A <-> A\" for a variance or \"A <-> B\" for a covariance (i.e., a double-headed or bidirectional arrow). Here, \\( A \\) and \\( B \\) are variable names in the model. If a name does not correspond to an observed variable, then it is assumed to be a latent variable. Spaces can appear freely in an arrow specification, and there can be any number of hyphens in the arrows, including zero: Thus, e.g., \"A->B\", \"A --B\", and \"A>B\" are all legitimate and equivalent.\n\n2. **Parameter name:** The name of the regression coefficient, variance, or covariance specified by the arrow. Assigning the same name to two or more arrows results in an equality constraint. Specifying the parameter name as NA produces a fixed parameter.\n3. **Value**: start value for a free parameter or value of a fixed parameter. If given as `NA`, `sem` will compute the start value.\n\nIt is simplest to construct the RAM matrix with the `specifyModel`, `specifyEquations`, or `cfa` function, all of which return an object of class `semmod`, and also incorporate some model-specification convenience shortcuts. This process is illustrated in the examples below.\n\nA numeric `ram` matrix consists of five columns, as follows:\n\n1. **Number of arrow heads**: 1 (directed arrow) or 2 (covariance).\n2. **Arrow to**: index of the variable at the head of a directional arrow, or at one end of a bidirectional arrow. Observed variables should be assigned the numbers 1 to $n$, where $n$ is the number of rows/columns in the covariance matrix $S$, with the indices corresponding to the variables' positions in $S$. Variable indices above $n$ represent latent variables.\n3. **Arrow from**: the index of the variable at the tail of a directional arrow, or at the other end of a bidirectional arrow.\n4. **Parameter number**: free parameters are numbered from 1 to $t$, but do not necessarily appear in consecutive order. Fixed parameters are given the number 0. Equality constraints are specified by assigning two or more parameters the same number.\n5. **Value**: start value for a free parameter, or value of a fixed parameter. If given as `NA`, the program will compute a start value, by a slight modification of the method described by McDonald and Hartmann (1992). Note: In some circumstances, some start values are selected randomly; this might produce small differences in the parameter estimates when the program is rerun.\n\nThe numeric `ram` matrix is normally generated automatically, not specified directly by the user. For `specifyEquations`, each input line is either a regression equation or the specification of a variance or covariance. Regression equations are of the form\n\n$$y = \\text{par}_1 x_1 + \\text{par}_2 x_2 + \\ldots + \\text{par}_k x_k$$\n\nwhere $y$ and the $x$s are variables in the model (either observed or latent), and the $\\text{par}$s are parameters. If a parameter is given as a numeric value (e.g., 1) then it is treated as fixed. Note that no “error” variable is included in the equation; “error variances” are specified via either the `covs` argument, via $V(y) = \\text{par}$ (see immediately below), or are added automatically to the model when, as by default, `endog.variances=TRUE`.\n\nVariances are specified in the form $V(\\text{var}) = \\text{par}$ and covariances in the form $C(\\text{var}_1, \\text{var}_2) = \\text{par}$, where the $\\text{var}$s are variables (observed or unobserved) in the model. The symbols $V$ and $C$ may be in either lower- or upper-case. If $\\text{par}$ is a numeric value (e.g., 1) then it is treated as fixed. In conformity with the RAM model, a variance or covariance for an endogenous variable in the model is an “error” variance or covariance.\n\nTo set a start value for a free parameter, enclose the numeric start value in parentheses after the parameter name, as `parameter(value)`.\n\n`sem` fits the model by calling the optimizer specified in the `optimizer` argument to minimize the objective function specified in the `objective` argument. If the optimization fails to converge, a warning message is printed.\n\nThe RAM formulation of the general structural equation model is given by the basic equation\n\n$$v = Av + u$$\nwhere \\( v \\) and \\( u \\) are vectors of random variables (observed or unobserved), and the parameter matrix \\( A \\) contains regression coefficients, symbolized by single-headed arrows in a path diagram. Another parameter matrix,\n\n\\[\nP = E(uu')\n\\]\n\ncontains covariances among the elements of \\( u \\) (assuming that the elements of \\( u \\) have zero means). Usually \\( v \\) contains endogenous and exogenous observed and unobserved variables, but not error variables (see the examples below).\n\nThe \\texttt{startvalues} function may be called directly, but is usually called by \\texttt{sem.default}; \\texttt{startvalues2} is an older version of this function that may be used alternatively; see the \\texttt{startvalues} argument to \\texttt{sem}.\n\n**Value**\n\n\\texttt{sem} returns an object of class \\( \\texttt{c(objective, \"sem\"}) \\), where \\texttt{objective} is the name of the objective function that was optimized (e.g., \"\\texttt{objectiveML}\"), with the following elements:\n\n- \\texttt{var.names} vector of variable names.\n- \\texttt{ram} RAM matrix, including any rows generated for covariances among fixed exogenous variables; column 5 includes computed start values.\n- \\texttt{S} observed covariance matrix.\n- \\texttt{J} RAM selection matrix, \\( J \\), which picks out observed variables.\n- \\texttt{n.fix} number of fixed exogenous variables.\n- \\texttt{n} number of observed variables.\n- \\texttt{N} number of observations.\n- \\texttt{m} number of variables (observed plus unobserved).\n- \\texttt{t} number of free parameters.\n- \\texttt{raw} TRUE if the model is fit to a raw moment matrix, FALSE otherwise.\n- \\texttt{data} the observed-variable data matrix, or NULL if data are not supplied.\n- \\texttt{semmod} the \\texttt{semmod} specification object for the model, if one was supplied; otherwise NULL.\n- \\texttt{optimizer} the optimizer function.\n- \\texttt{objective} the objective function.\n- \\texttt{coeff} estimates of free parameters.\n- \\texttt{vcov} estimated asymptotic covariance matrix of parameter estimates, based on a numeric Hessian, if supplied by the optimizer; otherwise NULL.\n- \\texttt{par.posn} indices of free parameters.\n- \\texttt{convergence} TRUE or FALSE, depending upon whether the optimization apparently converged.\n- \\texttt{iterations} number of iterations performed.\n- \\texttt{criterion} value of the objective function at the minimum.\n- \\texttt{C} model-reproduced covariance matrix.\n- \\texttt{A} RAM \\( A \\) matrix.\nsem\n\nP matrix.\n\nadj.obj robust adjusted value of the objective function; NULL if robust is FALSE.\n\nrobust.vcov robust estimated coefficient covariance matrix; NULL if robust is FALSE.\n\nFor multigroup models, sem returns an object of class c(\"msemObjectiveML\", \"msem\").\n\nWarning\n\nA common error is to fail to specify variance or covariance terms in the model, which are denoted by double-headed arrows, <->.\n\nIn general, every observed or latent variable in the model should be associated with a variance or error variance. This may be a free parameter to estimate or a fixed constant (as in the case of a latent exogenous variable for which you wish to fix the variance, e.g., to 1). Again in general, there will be an error variance associated with each endogenous variable in the model (i.e., each variable to which at least one single-headed arrow points — including observed indicators of latent variables), and a variance associated with each exogenous variable (i.e., each variable that appears only at the tail of single-headed arrows, never at the head).\n\nTo my knowledge, the only apparent exception to this rule is for observed variables that are declared to be fixed exogenous variables. In this case, the program generates the necessary (fixed-constant) variances and covariances automatically.\n\nIf there are missing variances, a warning message will be printed, and estimation will almost surely fail in some manner. Missing variances might well indicate that there are missing covariances too, but it is not possible to deduce this in a mechanical manner. The specifyModel function will by default supply error-variance parameters if these are missing.\n\nAuthor(s)\n\nJohn Fox <jfox@mcmaster.ca>, Zhenghua Nie, and Jarrett Byrnes\n\nReferences\n\n\nSee Also\nrawMoments, startvalues, objectiveML, objectiveGLS, optimizerNlm, optimizerOptim, optimizerNlminb, nlm, optim, nlminb, specifyModel, specifyEquations, cfa\n\nExamples\n\n# The following example illustrates the use the text argument to\n# readMoments() and specifyEquations():\n\nR.DHP <- readMoments(diag=FALSE, names=c(\"ROccAsp\", \"REdAsp\", \"FOccAsp\", \n \"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"),\n text=\"\n .6247\n .3269 .3669\n .4216 .3275 .6404\n .2137 .2742 .1124 .0839\n .4105 .4043 .2903 .2598 .1839\n .3240 .4047 .3054 .2786 .0489 .2220\n .2930 .2407 .4105 .3607 .0186 .1861 .2707\n .2995 .2863 .5191 .5007 .0782 .3355 .2382 .2950\n .0760 .0702 .2784 .1988 .1147 .1201 .0931 -.0438 .2087\n\"\n\nmodel.dhp.1 <- specifyEquations(covs=\"RGenAsp, FGenAsp\", text=\"RGenAsp = gam11*RParAsp + gam12*RIQ + gam13*RSES + gam14*RSES + beta12*FGenAsp\nFGenAsp = gam23*RSES + gam24*FSES + gam25*FIQ + gam26*FParAsp + beta21*RGenAsp\nROccAsp = 1*RGenAsp\nREdAsp = lam21(1)*RGenAsp # to illustrate setting start values\nFOccAsp = 1*FGenAsp\nFEdAsp = lam42(1)*FGenAsp\"\n\nsem.dhp.1 <- sem(model.dhp.1, R.DHP, 329,\n fixed.x=c(\"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"))\nsummary(sem.dhp.1)\n\n# Note: The following set of examples can't be run via example() because the default file\n# argument of specifyEquations, specifyModel(), and readMoments() requires that the model\n# specification and covariances, correlations, or raw moments be entered in an interactive\n# session at the command prompt. The examples can be copied and run in the R console,\n# however. See ?specifyModel and ?readMoments for further information.\n# These examples are repeated below using file input to specifyModel() and\n# readMoments(). The second version of the examples may be executed through example().\n\n## Not run:\n\n### Not run:\n# ------------- Duncan, Haller and Portes peer-influences model ----------------------\n# A nonrecursive SEM with unobserved endogenous variables and fixed exogenous variables\n\nR.DHP <- readMoments(diag=FALSE, names=c(\"ROccAsp\", \"REdAsp\", \"FOccAsp\", \"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"))\n\n.6247\n.3269 .3669\n.4216 .3275 .6404\n.2137 .2742 .1124 .0839\n.4105 .4043 .2903 .2598 .1839\n.3240 .4047 .3054 .2786 .0489 .2220\n.2930 .2407 .4105 .3607 .0186 .1861 .2707\n.2995 .2863 .5191 .5007 .0782 .3355 .2302 .2950\n.0760 .0702 .2784 .1988 .1147 .1021 .0931 -.0438 .2087\n\n# Fit the model using a symbolic ram specification\n\nmodel.dhp <- specifyModel()\nRParAsp -> RGenAsp, gam11, NA\nRIQ -> RGenAsp, gam12, NA\nRSES -> RGenAsp, gam13, NA\nFSES -> RGenAsp, gam14, NA\nRSES -> FGenAsp, gam23, NA\nFSES -> FGenAsp, gam24, NA\nFIQ -> FGenAsp, gam25, NA\nFParAsp -> FGenAsp, gam26, NA\nFGenAsp -> RGenAsp, beta12, NA\nRGenAsp -> FGenAsp, beta21, NA\nRGenAsp -> ROccAsp, NA, 1\nRGenAsp -> REdAsp, lam21, NA\nFGenAsp -> FOccAsp, NA, 1\nFGenAsp -> FEdAsp, lam42, NA\nRGenAsp <-> RGenAsp, ps11, NA\nFGenAsp <-> FGenAsp, ps22, NA\nRGenAsp <-> FGenAsp, ps12, NA\nROccAsp <-> REdAsp, theta1, NA\nREdAsp <-> REdAsp, theta2, NA\nFOccAsp <-> FOccAsp, theta3, NA\nFEdAsp <-> FEdAsp, theta4, NA\n\n# an equivalent specification, allowing specifyModel() to generate\n# variance parameters for endogenous variables (and suppressing the\n# unnecessary NAs):\n\nmodel.dhp <- specifyModel()\nRParAsp -> RGenAsp, gam11\nRIQ -> RGenAsp, gam12\nRSES -> RGenAsp, gam13\nFSES -> RGenAsp, gam14\nRSES -> FGenAsp, gam23\nFSES -> FGenAsp, gam24\nFIQ -> FGenAsp, gam25\nFParAsp -> FGenAsp, gam26\nFGenAsp -> RGenAsp, beta12\nRGenAsp -> FGenAsp, beta21\nRGenAsp -> ROccAsp, NA, 1\nRGenAsp -> REdAsp, lam21\nFGenAsp -> FOccAsp, NA, 1\nFGenAsp -> FEdAsp, lam42\nRGenAsp <-> FGenAsp, ps12\n\n# Another equivalent specification, telling specifyModel to add paths for\n# variances and covariance of RGenAsp and FGenAsp:\nmodel.dhp <- specifyModel(covs=\"RGenAsp, FGenAsp\")\nRParAsp -> RGenAsp, gam11\nRIQ -> RGenAsp, gam12\nRSES -> RGenAsp, gam13\nFSES -> RGenAsp, gam14\nRSES -> FGenAsp, gam23\nFSES -> FGenAsp, gam24\nFIQ -> FGenAsp, gam25\nFParAsp -> FGenAsp, gam26\nFGenAsp -> RGenAsp, beta12\nRGenAsp -> FGenAsp, beta21\nRGenAsp -> ROccAsp, NA, 1\nRGenAsp -> REdAsp, lam21\nFGenAsp -> FOccAsp, NA, 1\nFGenAsp -> FEdAsp, lam42\n\n# Yet another equivalent specification using specifyEquations():\nmodel.dhp.1 <- specifyEquations(covs=\"RGenAsp, FGenAsp\")\nRGenAsp = gam11*RParAsp + gam12*RIQ + gam13*RSES + gam14*FSES + beta12*FGenAsp\nFGenAsp = gam23*RSES + gam24*FSES + gam25*FIQ + gam26*FParAsp + beta21*RGenAsp\nROccAsp = 1*RGenAsp\nREdAsp = lam21(RGenAsp) # to illustrate setting start values\nFOccAsp = 1*FGenAsp\nFEdAsp = lam42(FGenAsp)\n\nsem.dhp.1 <- sem(model.dhp.1, R.DHP, 329,\n... fixed.x=c('RParAsp', 'RIQ', 'RSES', 'FSES', 'FIQ', 'FParAsp'))\ns\nsummary(sem.dhp.1)\n\n# Fit the model using a numerical ram specification (not recommended!)\nram.dhp <- matrix(c(\n1, 1, 11, 0, 1,\n1, 2, 11, 1, NA, # lam21\n1, 3, 12, 0, 1,\n1, 4, 12, 2, NA, # lam42\n1, 11, 5, 3, NA, # gam11\n1, 11, 6, 4, NA, # gam12\n1, 11, 7, 5, NA, # gam13\n1, 11, 8, 6, NA, # gam14\n...\nsem\n\n1, 12, 7, 7, NA, # gam23\n1, 12, 8, 8, NA, # gam24\n1, 12, 9, 9, NA, # gam25\n1, 12, 10, 10, NA, # gam26\n1, 11, 12, 11, NA, # beta12\n1, 12, 11, 12, NA, # beta21\n2, 1, 1, 13, NA, # theta1\n2, 2, 2, 14, NA, # theta2\n2, 3, 3, 15, NA, # theta3\n2, 4, 4, 16, NA, # theta4\n2, 11, 12, 17, NA, # psi11\n2, 12, 12, 18, NA, # psi22\n2, 11, 12, 19, NA # psi12\n)\n\nncol=5, byrow=TRUE)\n\nparams.dhp <- c('lam21', 'lam42', 'gam11', 'gam12', 'gam13', 'gam14',\n'gam23', 'gam24', 'gam25', 'gam26',\n'beta12', 'beta21', 'theta1', 'theta2', 'theta3', 'theta4',\n'psi11', 'psi22', 'psi12')\n\nvars.dhp <- c('ROccAsp', 'REDAsp', 'FOccAsp', 'FEdAsp', 'RIQ',\n'RSES', 'FSES', 'FIQ', 'FParAsp', 'RGenAsp', 'FGenAsp')\n\nsem.dhp.2 <- sem(ram.dhp, R.DHP, 329, param.names=params.dhp, var.names=vars.dhp,\nfixed.x=5:10)\n\nsummary(sem.dhp.2)\n\n# -------------------- Wheaton et al. alienation data ----------------------\n\nS.wh <- readMoments(names=c('Anomia67', 'Powerless67', 'Anomia71',\n'Powerless71', 'Education', 'SEI'))\n\n11.834\n6.947 9.364\n6.819 5.891 12.532\n4.783 5.028 7.495 9.986\n\n# This is the model in the SAS manual for PROC CALIS: A Recursive SEM with\n# latent endogenous and exogenous variables.\n# Curiously, both factor loadings for two of the latent variables are fixed.\n\nmodel.wh.1 <- specifyModel()\n\nAlienation67 -> Anomia67, NA, 1\nAlienation67 -> Powerless67, NA, 0.833\nAlienation71 -> Anomia71, NA, 1\nAlienation71 -> Powerless71, NA, 0.833\nSES -> Education, NA, 1\nSES -> SEI, lamb, NA\nSES -> Alienation67, gam1, NA\nAlienation67 -> Alienation71, beta, NA\nsem\n\nsem.wh.1 <- sem(model.wh.1, S.wh, 932)\nsummary(sem.wh.1)\n\n# The same model in equation format:\n\nmodel.wh.1 <- specifyEquations()\nAnomia67 = 1*Alienation67\nPowerless67 = 0.833*Alienation67\nAnomia71 = 1*Alienation71\nPowerless71 = 0.833*Alienation71\nEducation = 1*SES\nSEI = lamb*SES\nAlienation67 = gam1*SES\nAlienation71 = gam2*SES + beta*Alienation67\nV(Anomia67) = the1\nV(Anomia71) = the1\nV(Powerless67) = the2\nV(Powerless71) = the2\nV(SES) = phi\nC(Alienation67, Anomia67) = the5\nC(Powerless67, Powerless71) = the5\n\n# The same model, but treating one loading for each latent variable as free\n# (and equal to each other).\n\nmodel.wh.2 <- specifyModel()\nAlienation67 -> Anomia67, NA, 1\nAlienation67 -> Powerless67, lamby, NA\nAlienation71 -> Anomia71, NA, 1\nAlienation71 -> Powerless71, lamby, NA\nSES -> Education, NA, 1\nSES -> SEI, lambx, NA\nSES -> Alienation67, gam1, NA\nAlienation67 -> Alienation71, beta, NA\nSES -> Alienation71, gam2, NA\nAnomia67 <-> Anomia67, the1, NA\nAnomia71 <-> Anomia71, the1, NA\nPowerless67 <-> Powerless67, the2, NA\nPowerless71 <-> Powerless71, the2, NA\nEducation <-> Education, the3, NA\nsem\n\nSEI <-> SEI, the4, NA\nAnomia67 <-> Anomia71, the5, NA\nPowerless67 <-> Powerless71, the5, NA\nAlienation67 <-> Alienation67, psi1, NA\nAlienation71 <-> Alienation71, psi2, NA\nSES <-> SES, phi, NA\n\nsem.wh.2 <- sem(model.wh.2, S.wh, 932)\nsummary(sem.wh.2)\n\n# And again, in equation format:\n\nmodel.wh <- specifyEquations()\nAnomia67 = 1*Alienation67\nPowerless67 = lamby*Alienation67\nAnomia71 = 1*Alienation71\nPowerless71 = lamby*Alienation71\nEducation = 1*SES\nSEI = lambx*SES\nAlienation67 = gam1*SES\nAlienation71 = gam2*SES + beta*Alienation67\nV(Anomia67) = the1\nV(Anomia71) = the1\nV(Powerless67) = the2\nV(Powerless71) = the2\nV(SES) = phi\nC(Anomia67, Anomia71) = the5\nC(Powerless67, Powerless71) = the5\n\n# Compare the two models by a likelihood-ratio test:\n\nanova(sem.wh.1, sem.wh.2)\n\n# ----------------------- Thurstone data ---------------------------------------\n# Second-order confirmatory factor analysis, from the SAS manual for PROC CALIS\n\n\n.828 .776 .779\n.439 .493 .46 .432 .464 .425 .674\n.447 .489 .443 .59 .541 .447 .432 .401 .381 .402 .288 .541 .537 .534 .35 .367 .32 .555 .38 .358 .359 .424 .446 .325 .598 .452\n\nmodel.thur <- specifyModel()\nF1 -> Sentences, lam11\nF1 -> Vocabulary, lam21\nF1 -> Sent.Completion, lam31\nF2 -> First.Letters, lam42\nF2 -> 4.Letter.Words, lam52\nF2 -> Suffixes, lam62\nF3 -> Letter.Series, lam73\nF3 -> Pedigrees, lam83\nF3 -> Letter.Group, lam93\nF4 -> F1, gam1\nF4 -> F2, gam2\nF4 -> F3, gam3\nF1 <-> F1, NA, 1\nF2 <-> F2, NA, 1\nF3 <-> F3, NA, 1\nF4 <-> F4, NA, 1\n\nsem.thur <- sem(model.thur, R.thur, 213)\nsummary(sem.thur)\n\n# The model in equation format:\n\nmodel.thur <- specifyEquations()\nSentences = lam11*F1\nVocabulary = lam21*F1\nSent.Completion = lam31*F1\nFirst.Letters = lam42*F2\n4.Letter.Words = lam52*F2\nSuffixes = lam62*F2\nLetter.Series = lam73*F3\nPedigrees = lam83*F3\nLetter.Group = lam93*F3\nF1 = gam1*F4\nF2 = gam2*F4\nF3 = gam3*F4\nV(F1) = 1\nV(F2) = 1\nV(F3) = 1\nV(F4) = 1\n\n#------------------------- Kerchoff/Kenney path analysis ---------------------\n# An observed-variable recursive SEM from the LISREL manual\n\nR.kerch <- readMoments(diag=FALSE, names=c('Intelligence', 'Siblings',\n 'FatherEd', 'FatherOcc', 'Grades', 'EducExp', 'OccupAsp'))\n\nmodel.kerch <- specifyModel()\nIntelligence -> Grades, \\(\\text{gam}51\\)\nSiblings -> Grades, \\(\\text{gam}52\\)\nFatherEd -> Grades, \\(\\text{gam}53\\)\nFatherOcc -> Grades, \\(\\text{gam}54\\)\nIntelligence -> EducExp, \\(\\text{gam}61\\)\nSiblings -> EducExp, \\(\\text{gam}62\\)\nFatherEd -> EducExp, \\(\\text{gam}63\\)\nFatherOcc -> EducExp, \\(\\text{gam}64\\)\nGrades -> EducExp, \\(\\beta\\text{eta}65\\)\nIntelligence -> OccupAsp, \\(\\text{gam}71\\)\nSiblings -> OccupAsp, \\(\\text{gam}72\\)\nFatherEd -> OccupAsp, \\(\\text{gam}73\\)\nFatherOcc -> OccupAsp, \\(\\text{gam}74\\)\nGrades -> OccupAsp, \\(\\beta\\text{eta}75\\)\nEducExp -> OccupAsp, \\(\\beta\\text{eta}76\\)\n\n\\(\\text{sem}\\.\\text{kerch} \\leftarrow \\text{sem}(\\text{model}\\.\\text{kerch}, \\text{R}\\.\\text{kerch}, 737,\\)\nfixed.x=c('\\text{Intelligence}', 'Siblings', 'FatherEd', 'FatherOcc'))\nsummary(\\text{sem}\\.\\text{kerch})\n\n# The model in equation format:\n\\text{model}\\.\\text{kerch} \\leftarrow \\text{specifyEquations}()\n\\text{Grades} = \\text{gam}51*\\text{Intelligence} + \\text{gam}52*\\text{Siblings} + \\text{gam}53*\\text{FatherEd} + \\text{gam}54*\\text{FatherOcc}\n\\text{EducExp} = \\text{gam}61*\\text{Intelligence} + \\text{gam}62*\\text{Siblings} + \\text{gam}63*\\text{FatherEd} + \\text{gam}64*\\text{FatherOcc} + \\beta\\text{eta}65*\\text{Grades}\n\\text{OccupAsp} = \\text{gam}71*\\text{Intelligence} + \\text{gam}72*\\text{Siblings} + \\text{gam}73*\\text{FatherEd} + \\text{gam}74*\\text{FatherOcc} + \\beta\\text{eta}75*\\text{Grades} + \\beta\\text{eta}76*\\text{EducExp}\n\n#------------------- McArdle/Epstein latent-growth-curve model -------------------\n# This model, from McArdle and Epstein (1987, p.118), illustrates the use of a\n# raw moment matrix to fit a model with an intercept. (The example was suggested\n# by Mike Stoolmiller.)\n\\text{M}\\.\\text{McArdle} \\leftarrow \\text{readMoments}(\n\\text{names}=(\\text{\\textquote{WISC}1}, \\text{\\textquote{WISC}2}, \\text{\\textquote{WISC}3}, \\text{\\textquote{WISC}4}, \\text{UNIT}))\n365.661\n503.175 719.905\n675.656 958.479 1303.392\n890.680 1265.846 1712.475 2278.257\n18.034 25.819 35.255 46.593 1.000\n\\text{mod}\\.\\text{McArdle} \\leftarrow \\text{specifyModel}()\n\\text{C} -> \\text{WISC}1, \\text{NA}, 6.07\n\\text{C} -> \\text{WISC}2, B2, \\text{NA}\n\\text{C} -> \\text{WISC}3, B3, \\text{NA}\n\\text{C} -> \\text{WISC}4, B4, \\text{NA}\n\\text{UNIT} -> \\text{C, Mc}, \\text{NA}\n\\text{C} <-> \\text{C, Vc}, \\text{NA},\n\\text{WISC}1 <-> \\text{WISC}1, Vd, \\text{NA}\n\\text{WISC}2 <-> \\text{WISC}2, Vd, \\text{NA}\n#### WISC3 <-> WISC3, Vd, NA\n#### WISC4 <-> WISC4, Vd, NA\n\nsem.McArdle <- sem(mod.McArdle, M.McArdle, 204, fixed.x=\"UNIT\", raw=TRUE)\nsummary(sem.McArdle)\n\n# The model in equation format:\n\nmod.McArdle <- specifyEquations()\nWISC1 = 6.07*C\nWISC2 = B2*C\nWISC3 = B3*C\nWISC4 = b4*C\nC = Mc*UNIT\nv(C) = Vc\nv(WISC1) = Vd\nv(WISC2) = Vd\nv(WISC3) = Vd\nv(WISC4) = Vd\n\n#------------ Bollen industrialization and democracy example -----------------\n# This model, from Bollen (1989, Ch. 8), illustrates the use in sem() of a case-by-variable data (see ?Bollen) set rather than a covariance or moment matrix\n\nmodel.bollen <- specifyModel()\nDemo60 -> y1, NA, 1\nDemo60 -> y2, lam2,\nDemo60 -> y3, lam3,\nDemo60 -> y4, lam4,\nDemo65 -> y5, NA, 1\nDemo65 -> y6, lam2,\nDemo65 -> y7, lam3,\nDemo65 -> y8, lam4,\nIndust -> x1, NA, 1\nIndust -> x2, lam6,\nIndust -> x3, lam7,\ny1 <-> y5, theta15\ny2 <-> y4, theta24\ny2 <-> y6, theta26\ny3 <-> y7, theta37\ny4 <-> y8, theta48\ny6 <-> y8, theta68\nIndust -> Demo60, gamma11,\nIndust -> Demo65, gamma21,\nDemo60 -> Demo65, beta21,\nIndust <-> Indust, phi\n\nsem.bollen <- sem(model.bollen, data=Bollen)\nsummary(sem.bollen)\nsummary(sem.bollen, robust=TRUE) # robust SEs and tests\nsummary(sem.bollen, analytic.se=FALSE) # uses numeric rather than analytic Hessian\n# GLS rather than ML estimator:\nsem.bollen.gls <- sem(model.bollen, data=Bollen, objective=objectiveGLS)\nsummary(sem.bollen.gls)\n\n# The model in equation format:\nmodel.bollen <- specifyEquations()\ny1 = 1*Demo60\ny2 = lam2*Demo60\ny3 = lam3*Demo60\ny4 = lam4*Demo60\ny5 = 1*Demo65\ny6 = lam2*Demo65\ny7 = lam3*Demo65\ny8 = lam4*Demo65\nx1 = 1*Indust\nx2 = lam6*Indust\nx3 = lam7*Indust\nc(y1, y5) = theta15\nc(y2, y4) = theta24\nc(y2, y6) = theta26\nc(y3, y7) = theta37\nc(y4, y8) = theta48\nc(y6, y8) = theta68\nDemo60 = gamma11*Indust\nDemo65 = gamma21*Indust + beta21*Demo60\nv(Indust) = phi\n\n# -------------- A simple CFA model for the Thurstone mental tests data --------------\nR.thur <- readMoments(diag=FALSE,\n names=c('Sentences', 'Vocabulary',\n 'Letter.Series', 'Pedigrees', 'Letter.Group'))\n\n.828\n.776 .779\n.439 .493 .46\n.432 .464 .425 .674\n.447 .489 .443 .59 .541\n.447 .432 .401 .381 .482 .288\n.541 .537 .534 .35 .367 .32 .555\n.38 .358 .359 .424 .446 .325 .598 .452\n\n# (1) in CFA format:\nmod.cfa.thur.c <- cfa(reference.indicators=FALSE)\nFA: Sentences, Vocabulary, Sent.Completion\nFC: Letter.Series, Pedigrees, Letter.Group\n\ncfa.thur.c <- sem(mod.cfa.thur.c, R.thur, 213)\nsummary(cfa.thur.c)\n# (2) in equation format:\n\n```r\nmod.cfa.thur.e <- specifyEquations(covs=\"F1, F2, F3\")\nSentences = lam11*F1\nVocabulary = lam21*F1\nSent.Completion = lam31*F1\nFirst.Letters = lam42*F2\n4.Letter.Words = lam52*F2\nSuffixes = lam62*F2\nLetter.Series = lam73*F3\nPedigrees = lam83*F3\nLetter.Group = lam93*F3\nV(F1) = 1\nV(F2) = 1\nV(F3) = 1\n```\n\ncfa.thur.e <- sem(mod.cfa.thur.e, R.thur, 213)\nsummary(cfa.thur.e)\n\n# (3) in path format:\n\n```r\nmod.cfa.thur.p <- specifyModel(covs=\"F1, F2, F3\")\nF1 -> Sentences, lam11\nF1 -> Vocabulary, lam21\nF1 -> Sent.Completion, lam31\nF2 -> First.Letters, lam41\nF2 -> 4.Letter.Words, lam52\nF2 -> Suffixes, lam62\nF3 -> Letter.Series, lam73\nF3 -> Pedigrees, lam83\nF3 -> Letter.Group, lam93\nF1 <-> F1, NA, 1\nF2 <-> F2, NA, 1\nF3 <-> F3, NA, 1\n```\n\ncfa.thur.p <- sem(mod.cfa.thur.p, R.thur, 213)\nsummary(cfa.thur.p)\n\n# ---- a CFA model fit by FIML to the mental-tests dataset with missing data -----\n\n```r\nmod.cfa.tests <- cfa(raw=TRUE)\nverbal: x1, x2, x3\nmath: y1, y2, y3\ncfa.tests <- sem(mod.cfa.tests, data=Tests, na.action=na.pass,\n objective=objectiveFIML, fixed.x=\"Intercept\")\nsummary(cfa.tests)\nsummary(cfa.tests, saturated=TRUE) # takes time to fit saturated model for comparison\n```\n\n# --- a multigroup CFA model fit to the Holzinger-Swineford mental-tests data ---\nmod.hs <- cfa()\nspatial: visual, cubes, paper, flags\nverbal: general, paragrap, sentence, wordc, wordm\nmemory: wordr, numberr, figurer, object, numberf, figurew\nmath: deduct, numeric, problemr, series, arithmet\n\nmod.mg <- multigroupModel(mod.hs, groups=c(\"Female\", \"Male\"))\n\nsem.mg <- sem(mod.mg, data=HS.data, group=\"Gender\",\nformula = ~ visual + cubes + paper + flags +\ngeneral + paragrap + sentence + wordc + wordm +\nwordr + numberr + figurer + object + numberf + figurew +\ndeduct + numeric + problemr + series + arithmet\n)\n\nsummary(sem.mg)\n\n# with cross-group equality constraints:\n\nmod.mg.eq <- multigroupModel(mod.hs, groups=c(\"Female\", \"Male\"), allEqual=TRUE)\n\nsem.mg.eq <- sem(mod.mg.eq, data=HS.data, group=\"Gender\",\nformula = ~ visual + cubes + paper + flags +\ngeneral + paragrap + sentence + wordc + wordm +\nwordr + numberr + figurer + object + numberf + figurew +\ndeduct + numeric + problemr + series + arithmet\n)\n\nsummary(sem.mg.eq)\n\nanova(sem.mg, sem.mg.eq) # test equality constraints\n\n## End(Not run)\n\n# The following examples use file input and may be executed via example():\n\nect <- system.file(package=\"sem\", \"etc\") # path to data and model files\n\n# to get all fit indices (not recommended, but for illustration):\n\nopt <- options(fit.indices = c(\"GFI\", \"AGFI\", \"RMSEA\", \"NFI\", \"NNFI\",\n\"CFI\", \"RNI\", \"IFI\", \"SRMR\", \"AIC\", \"AICC\", \"BIC\", \"CAIC\"))\n\n# -------------- Duncan, Haller and Portes peer-influences model -----------------\n# A nonrecursive SEM with unobserved endogenous variables and fixed exogenous variables\n\n(R.DHP <- readMoments(file=file.path(etc, \"R-DHP.txt\"),\ndiag=FALSE, names=c(\"R0ccAsp\", \"REdAsp\", \"F0ccAsp\",\n\"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\")))\n(model.dhp <- specifyModel(file=file.path(etc, \"model-DHP.txt\")))\n\nsem.dhp.1 <- sem(model.dhp, R.DHP, 329,\nfixed.x=c(\"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"))\n\nsummary(sem.dhp.1)\n# -------------- Wheaton et al. alienation data ---------------\n\n(S.wh <- readMoments(file=file.path(etc, \"S-Wheaton.txt\"),\n names=c('Anomia67','Powerless67','Anomia71',\n 'Powerless71','Education','SEI')))\n\n# This is the model in the SAS manual for PROC CALIS: A Recursive SEM with\n# latent endogenous and exogenous variables.\n# Curiously, both factor loadings for two of the latent variables are fixed.\n\n(model.wh.1 <- specifyModel(file=file.path(etc, \"model-Wheaton-1.txt\")))\nsem.wh.1 <- sem(model.wh.1, S.wh, 932)\nsummary(sem.wh.1)\n\n# The same model, but treating one loading for each latent variable as free\n# (and equal to each other).\n\n(model.wh.2 <- specifyModel(file=file.path(etc, \"model-Wheaton-2.txt\")))\nsem.wh.2 <- sem(model.wh.2, S.wh, 932)\nsummary(sem.wh.2)\n\n# Compare the two models by a likelihood-ratio test:\nanova(sem.wh.1, sem.wh.2)\n\n# ------------------- Thurstone data ----------------------------------\n\n# Second-order confirmatory factor analysis, from the SAS manual for PROC CALIS\n\n(R.thur <- readMoments(file=file.path(etc, \"R-Thurstone.txt\"),\n diag=FALSE, names=c('Sentences','Vocabulary',\n 'Letter.Series','Pedigrees', 'Letter.Group')))\n\n(model.thur <- specifyModel(file=file.path(etc, \"model-Thurstone.txt\")))\nsem.thur <- sem(model.thur, R.thur, 213)\nsummary(sem.thur)\n\n# --------------------- Kerchoff/Kenney path analysis ----------------- \n\n# An observed-variable recursive SEM from the LISREL manual\n\n(R.kerch <- readMoments(file=file.path(etc, \"R-Kerchoff.txt\"),\n diag=FALSE, names=c('Intelligence','Siblings',\n 'FatherEd','FatherOcc','Grades','EducExp','OccupAsp')))\n\n(model.kerch <- specifyModel(file=file.path(etc, \"model-Kerchoff.txt\")))\nsem.kerch <- sem(model.kerch, R.kerch, 737,\n fixed.x=c('Intelligence','Siblings', 'FatherEd', 'FatherOcc'))\nsummary(sem.kerch)\nsem\n\n#------------------- McArdle/Epstein latent-growth-curve model -----------------\n# This model, from McArdle and Epstein (1987, p.118), illustrates the use of a\n# raw moment matrix to fit a model with an intercept. (The example was suggested\n# by Mike Stoolmiller.)\n\n(M.McArdle <- readMoments(file=file.path(etc, \"M-McArdle.txt\"),\n names=c(\"WISC1\", \"WISC2\", \"WISC3\", \"WISC4\", \"UNIT\")))\n(mod.McArdle <- specifyModel(file=file.path(etc, \"model-McArdle.txt\")))\nsem.McArdle <- sem(mod.McArdle, M.McArdle, 204, fixed.x=\"UNIT\", raw=TRUE)\nsummary(sem.McArdle)\n\n#------------ Bollen industrialization and democracy example -----------------\n# This model, from Bollen (1989, Ch. 8), illustrates the use in sem() of a\n# case-by-variable data set (see ?Bollen) rather than a covariance or moment matrix\n\n(model.bollen <- specifyModel(file=file.path(etc, \"model-Bollen.txt\")))\nsem.bollen <- sem(model.bollen, data=Bollen)\nsummary(sem.bollen)\nsummary(sem.bollen, robust=TRUE) # robust SEs and tests\nsummary(sem.bollen, analytic.se=FALSE) # uses numeric rather than analytic Hessian\n\n # GLS rather than ML estimator:\nsem.bollen.gls <- sem(model.bollen, data=Bollen, objective=objectiveGLS)\nsummary(sem.bollen.gls)\n\n# ----- a CFA model fit by FIML to the mental-tests dataset with missing data ----- \n(mod.cfa.tests <- cfa(file=file.path(etc, \"model-Tests.txt\"), raw=TRUE))\ncfa.tests <- sem(mod.cfa.tests, data=Tests, na.action=na.pass,\n optimizer=optimizerNlm, objective=objectiveFIML, fixed.x=\"Intercept\")\nsummary(cfa.tests)\n\n#------------ Holzinger and Swineford multigroup CFA example ----------------\nmod.hs <- cfa(file=file.path(etc, \"model-HS.txt\"))\nmod.mg <- multigroupModel(mod.hs, groups=c(\"Female\", \"Male\"))\n\nsem.mg <- sem(mod.mg, data=HS.data, group=\"Gender\",\n formula = ~ visual + cubes + paper + flags +\n general + paragrap + sentence + wordc + wordm +\n wordr + numbere + figure + object + numberf + figurew +\n deduct + numeric + problemr + series + arithmet)\nsummary(sem.mg)\n\n # with cross-group equality constraints:\nmod.mg.eq <- multigroupModel(mod.hs, groups=c(\"Female\", \"Male\"), allEqual=TRUE)\nsem.mg.eq <- sem(mod.mg.eq, data=HS.data, group=\"Gender\",\n formula = ~ visual + cubes + paper + flags +\n general + paragrap + sentence + wordc + wordm +\n wordr + number + figure + object + numberf + figurew +\n deduct + numeric + problemr + series + arithmet\n )\nsummary(sem.mg.eq)\n\nanova(sem.mg, sem.mg.eq) # test equality constraints\n\noptions(opt) # restore fit.indices option\n\n---\n\n### sem-deprecated\n\n#### Deprecated Functions in the sem Package\n\n**Description**\n\nThese functions are provided for compatibility with older versions of the **sem** package only, and may be removed eventually. Although an effort has been made to insure backwards-compatibility, commands that worked in versions of the **sem** package prior to version 2.0-0 will not necessarily work in version 2.0-0 and beyond, or may not work in the same manner.\n\n**Usage**\n\n- `boot.sem(...)`\n- `mod.indices(...)`\n- `normalized.residuals(...)`\n- `path.diagram(...)`\n- `raw.moments(...)`\n- `read.moments(...)`\n- `specify.model(...)`\n- `standardized.coefficients(...)`\n- `standardized.residuals(...)`\n- `std.coef(...)`\n\n**Arguments**\n\n... pass arguments down to replacements for deprecated functions.\n\n**Details**\n\n- `boot.sem` is now a synonym for the `bootSem` function.\n- `mod.indices` is now a synonym for `modIndices`.\n- `normalized.residuals` is now a synonym for `normalizedResiduals`.\n- `path.diagram` is now a synonym for `pathDiagram`. \nraw.moments is now a synonym for rawMoments.\nread.moments is now a synonym for readMoments.\nspecify.model is now a synonym for specifyModel.\nstandardized.coefficients and std.coef are now synonyms for the standardizedCoefficients and stdCoef functions.\nstandardized.residuals is now a synonym for standardizedResiduals.\n\n---\n\n**specifyModel**\n\n*Specify a Structural Equation Model*\n\n**Description**\n\nCreate the RAM specification of a structural equation model.\n\n**Usage**\n\n```r\nspecifyModel(file=\"\", text, exog.variances=FALSE, endog.variances=TRUE, covs,\n suffix=\"\", quiet=FALSE)\n\nspecifyEquations(file=\"\", text, ...)\n\ncfa(file=\"\", text, covs=paste(factors, collapse=\",\"),\n reference.indicators=TRUE, raw=FALSE,\n subscript=c(\"name\", \"number\"), ...)\n\nmultigroupModel(..., groups=names(models), allEqual=FALSE)\n\nclassifyVariables(model)\n\nremoveRedundantPaths(model, warn=TRUE)\n## S3 method for class 'semmod'\ncombineModels(..., warn=TRUE)\n## S3 method for class 'semmod'\nupdate(object, file = \"\", text, ...)\n## S3 method for class 'semmod'\nedit(name, ...)\n\n## S3 method for class 'semmod'\nprint(x, ...)\n## S3 method for class 'semmodList'\nprint(x, ...)\n```\n**Arguments**\n\n- **file**\nThe (quoted) file from which to read the model specification, including the path to the file if it is not in the current directory. If \"\" (the default) and the text argument is not supplied, then the specification is read from the standard input stream, and is terminated by a blank line.\n\n- **text**\nThe model specification given as a character string, as an alternative to specifying the `file` argument or reading the model specification from the input stream — e.g., when the session is not interactive and there is no standard input.\n\n- **exog.variances**\nIf TRUE (the default is FALSE), free variance parameters are added for the exogenous variables that lack them.\n\n- **endog.variances**\nIf TRUE (the default), free error-variance parameters are added for the endogenous variables that lack them.\n\n- **covs**\noptional: a character vector of one or more elements, with each element giving a string of variable names, separated by commas. Variances and covariances among all variables in each such string are added to the model. For confirmatory factor analysis models specified via `cfa`, `covs` defaults to all of the factors in the model, thus specifying all variances and covariances among these factors. **Warning**: `covs=\"x1,x2\"` and `covs=c(\"x1\",\"x2\")` are not equivalent: `covs=\"x1,x2\"` specifies the variance of `x1`, the variance of `x2`, and their covariance, while `covs=c(\"x1\",\"x2\")` specifies the variance of `x1` and the variance of `x2` but not their covariance.\n\n- **suffix**\na character string (defaulting to an empty string) to be appended to each parameter name; this can be convenient for specifying multiple-group models.\n\n- **reference.indicators**\nif FALSE, the default, variances of factors are set to 1 by `cfa`; if TRUE, variances of factors are free parameters to estimate from the data, and instead the first factor loading for each factor is set to 1 to identify the model.\n\n- **raw**\nif TRUE (the default is FALSE), a path from Intercept to each observed variable is added to the model, and the raw second moment for Intercept is fixed to 1. The `sem` function should then be called with `raw=TRUE`, and either supplied with a data set (via the `data` argument) or a raw-moment matrix (via the `S` argument).\n\n- **subscript**\nThe “subscripts” to be appended to `lam` to name factor-loading parameters, either \"name\" (the default) to use the names of observed variables, or \"number\" to number the parameters serially within each factor. Using \"number\" produces shorter parameter names.\n\n- **quiet**\nif FALSE, the default, then the number of input lines is reported and a message is printed suggesting that `specifyEquations` or `cfa` be used.\n\n- **x, model, object, name**\nAn object of class `semmod` or `semmodList`, as produced by `specifyModel` or `multigroupModel`.\n\n- **warn**\nprint a warning if redundant paths are detected.\n\n- **...**\nFor `multigroupModel`, one or more optionally named arguments each of which is a `semmod` object produced, e.g., by `specifyModel`, `specifyEquations`, or `cfa`; if only one such model is given, then it will be used for all groups defined.\nby the groups argument. If parameters have the same name in different groups, then they will be constrained to be equal. For specifyEquations and cfa, arguments (such as covs, in the case of specifyEquations) to be passed to specifyModel; for combineModels, sem objects; ignored in the update and print methods.\n\ngroups\na character vector of names for the groups in a multigroup model; taken by default from the names of the ... arguments.\n\nallEqual\nif FALSE (the default), then if only one model object is given for a multigroup model, all corresponding parameters in the groups will be distinct; if TRUE, all corresponding parameters will be constrained to be equal.\n\nDetails\nThe principal functions for model specification are specifyModel, to specify a model in RAM (path) format via single- and double-headed arrows; specifyEquations, to specify a model in equation format, which is then translated by the function into RAM format; and cfa, for compact specification of simple confirmatory factor analysis models.\n\nspecifyModel:\nEach line of the RAM specification for specifyModel consists of three (unquoted) entries, separated by commas:\n\n1. Arrow specification: This is a simple formula, of the form A -> B or, equivalently, B <-A for a regression coefficient (i.e., a single-headed or directional arrow); A <-> A for a variance or A <-> B for a covariance (i.e., a double-headed or bidirectional arrow). Here, A and B are variable names in the model. If a name does not correspond to an observed variable, then it is assumed to be a latent variable. Spaces can appear freely in an arrow specification, and there can be any number of hyphens in the arrows, including zero: Thus, e.g., A->B, A --> B, and A>B are all legitimate and equivalent.\n\n2. Parameter name: The name of the regression coefficient, variance, or covariance specified by the arrow. Assigning the same name to two or more arrows results in an equality constraint. Specifying the parameter name as NA produces a fixed parameter.\n\n3. Value: start value for a free parameter or value of a fixed parameter. If given as NA (or simply omitted), sem will compute the start value.\n\nLines may end in a comment following #.\n\nspecifyEquations:\nFor specifyEquations, each input line is either a regression equation or the specification of a variance or covariance. Regression equations are of the form\n\n\\[ y = par1*x1 + par2*x2 + \\ldots + par*k*xk \\]\n\nwhere y and the xs are variables in the model (either observed or latent), and the pars are parameters. If a parameter is given as a numeric value (e.g., 1) then it is treated as fixed. Note that no “error” variable is included in the equation; “error variances” are specified via either the covs argument, via \\( V(y) = par \\) (see immediately below), or are added automatically to the model when, as by default, endog.variances=TRUE. A regression equation may be split over more than one input by breaking at a +, so that + is either the last non-blank character on a line or the first non-blank character on the subsequent line.\nVariance specifications are written in the form $V(\\text{var}) = \\text{par}$ and $C(\\text{var}_1, \\text{var}_2) = \\text{par}$, where the vars are variables (observed or unobserved) in the model. The symbols $V$ and $C$ may be either lower- or upper-case. If $\\text{par}$ is a numeric value (e.g., 1) then it is treated as fixed. In conformity with the RAM model, a variance or covariance for an endogenous variable in the model is an \"error\" variance or covariance.\n\n**Warning:** If the covs argument to specifyEquations is used to specify variances and covariances, please be aware that covs=\"x1,x2\" and covs=c(\"x1\",\"x2\") are **not** equivalent: covs=\"x1,x2\" specifies the variance of $x_1$, the variance of $x_2$, and their covariance, while covs=c(\"x1\",\"x2\") specifies the variance of $x_1$ and the variance of $x_2$ but **not** their covariance.\n\nTo set a start value for a free parameter, enclose the numeric start value in parentheses after the parameter name, as parameter(value).\n\ncfa:\n\nFor cfa, each input line includes the names of the variables, separated by commas, that load on the corresponding factor; the name of the factor is given optionally at the beginning of the line, followed by a colon. If necessary, the variables that load on a factor may be continued across two or more input lines; in this case, each such line but the last must end in a comma. A variable may load on more than one factor (as long as the resulting model is identified, of course), but each factor may appear in only one input line (or set of input lines, if the variable list is continued onto the next line).\n\nEquality constraints for factor loadings can be set by using equal-signs (=) rather than commas to separate observed variable names. For example, fac1: x1=x2=x3,x4=x5 sets the loadings for $x_1$, $x_2$, and $x_3$ equal to each other, and the loadings for $x_4$ and $x_5$ equal to each other.\n\nEquality constraints among error variances can similarly be specified by using var: or variance: at the beginning of a line (actually, any character string beginning with var will do, and thus no factor name may begin with the characters var). For example, var: x1=x2=x3,x4=x5 sets the error variances for $x_1$, $x_2$, and $x_3$ equal to each other, and the error variances for $x_4$ and $x_5$ equal to each other. There may be several lines beginning with var:.\n\nIf the argument reference.indicators=FALSE, the default, cfa will fix the variance of each factor to 1, and by default include covariances (i.e., correlations) among all pairs of factors. Alternatively, if reference.indicators=TRUE, then the factor variances are free parameters to be estimated from the data, and the first loading for each factor is set to 1 to identify the model. These two approaches produce equivalent models, with the same fit to the data, but alternative parametrizations. Specifying the argument covs=NULL implicitly fixes the factor intercorrelations to 0.\n\nSee sem and the examples for further details on model specification.\n\nOther Functions:\n\nclassifyVariables classifies the variables in a model as endogenous or exogenous.\n\ncombineModels and removeRedundantPaths take semmod objects as arguments and do what their names imply.\n\nThe file input argument to the update method for semmod objects, which by default comes from standard input, is a set of update directives, one per line. There are five kinds of directives. In each case the directive begins with the directive name, followed by one or more fields separated by commas.\n\n1. **delete**: Remove a path from the model. Example: delete,RSES -> FGenAsp\nspecifyModel\n\n2. **add**: Add a path to the model. Example (the NA for the start value is optional): add,RSES -> FGenAsp,gam14,NA\n\n3. **replace**: Replace every occurrence of the first string with the second in the variables and parameters of the model. This directive may be used, for example, to change one variable to another or to rename a parameter. Example: replace,gam,gamma, substitutes the string \"gamma\" for \"gam\" wherever the latter appears, presumably in parameter names.\n\n4. **fix**: Fix a parameter that was formerly free. Example: fix,RGenAsp -> REdAsp,1\n\n5. **free**: Free a parameter that was formerly fixed. Example (the NA for the start value is optional): free,RGenAsp -> ROccAsp,lam11,NA\n\nThe edit method for semmod objects opens the model in the R editor.\n\n**Value**\n\nspecifyModel, specifyEquations, cfa, removeRedundantPaths, combineModels, update, and edit return an object of class semmod, suitable as input for sem. multigroupModel returns an object of class semmodList, also suitable as input for sem. classifyVariables returns a list with two character vectors: endogenous, containing the names of endogenous variables in the model; and exogenous, containing the names of exogenous variables.\n\n**Author(s)**\n\nJohn Fox <jfox@mcmaster.ca> and Jarrett Byrnes\n\n**See Also**\n\nsem\n\n**Examples**\n\n# example using the text argument:\n\n```r\nmodel.dhp <- specifyModel(text=\"\nRParAsp -> RGenAsp, gam11, NA\nRIQ -> RGenAsp, gam12, NA\nRSES -> RGenAsp, gam13, NA\nFSES -> RGenAsp, gam14, NA\nRSES -> FGenAsp, gam23, NA\nFSES -> FGenAsp, gam24, NA\nFIQ -> FGenAsp, gam25, NA\nFPARAsp -> FGenAsp, gam26, NA\nFGenAsp -> RGenAsp, beta12, NA\nRGenAsp -> FGenAsp, beta21, NA\nRGenAsp -> ROccAsp, NA, 1\nRGenAsp -> REdAsp, lam21, NA\nFGenAsp -> F0ccAsp, NA, 1\nFGenAsp -> FEdAsp, lam42, NA\nRGenAsp <-> RGenAsp, ps11, NA\nFGenAsp <-> FGenAsp, ps22, NA\n\n```\n\n```\nRGenAsp <-> FGenAsp, ps12, NA\nROccAsp <-> ROccAsp, theta1, NA\nREdAsp <-> REdAsp, theta2, NA\nFOccAsp <-> FOccAsp, theta3, NA\nFEdAsp <-> FEdAsp, theta4, NA\n\"\nmodel.dhp\n\n# same model in equation form:\nmodel.dhp.1 <- specifyEquations(covs=\"RGenAsp, FGenAsp\", text=\"\nRGenAsp = gam11*RParAsp + gam12*RlQ + gam13*RSES + gam14*FSES + beta12*FGenAsp\nFGenAsp = gam23*RSES + gam24*FSES + gam25*FIQ + gam26*FParAsp + beta21*RGenAsp\nROccAsp = 1*RGenAsp\nREdAsp = lam21(1)*RGenAsp # to illustrate setting start values\nFOccAsp = 1*FGenAsp\nFEdAsp = lam42(1)*FGenAsp\"\nmodel.dhp\n\n# Note: The following examples can’t be run via example() because the\n# default file argument requires that the model specification be entered\n# at the command prompt. The examples can be copied and run in an interactive\n# session in the R console, however.\n\n## Not run:\nmodel.dhp <- specifyModel()\nRParAsp -> RGenAsp, gam11, NA\nRIQ -> RGenAsp, gam12, NA\nRSES -> RGenAsp, gam13, NA\nFSES -> RGenAsp, gam14, NA\nRSES -> FGenAsp, gam23, NA\nFSES -> FGenAsp, gam24, NA\nFIQ -> FGenAsp, gam25, NA\nFParAsp -> FGenAsp, gam26, NA\nFGenAsp -> RGenAsp, beta12, NA\nRGenAsp -> FGenAsp, beta21, NA\nRGenAsp -> ROccAsp, NA, 1\nRGenAsp -> REdAsp, lam21, NA\nFGenAsp -> FOccAsp, NA, 1\nFGenAsp -> FEdAsp, lam42, NA\nRGenAsp <-> RGenAsp, ps11, NA\nFGenAsp <-> FGenAsp, ps22, NA\nRGenAsp <-> FGenAsp, ps12, NA\nROccAsp <-> ROccAsp, theta1, NA\nREdAsp <-> REdAsp, theta2, NA\nFOccAsp <-> FOccAsp, theta3, NA\nFEdAsp <-> FEdAsp, theta4, NA\n\nmodel.dhp\n\n# an equivalent specification, allowing specifyModel() to generate\n# variance parameters for endogenous variables (and suppressing\n# the unnecessary trailing NAs):\nmodel.dhp <- specifyModel()\nRParAsp -> RGenAsp, gam11\nRIQ -> RGenAsp, gam12\nRSES -> RGenAsp, gam13\nFSES -> RGenAsp, gam14\nRSES -> FGenAsp, gam23\nFSES -> FGenAsp, gam24\nFIQ -> FGenAsp, gam25\nFParAsp -> FGenAsp, gam26\nFGenAsp -> RGenAsp, gam14\nRGenAsp -> FGenAsp, beta12\nRGenAsp -> ROccAsp, NA, 1\nRGenAsp -> REdAsp, lam21\nFGenAsp -> FOccAsp, NA, 1\nFGenAsp -> FEdAsp, lam42\nRGenAsp <- FGenAsp, ps12\n\nmodel.dhp\n\n# Another equivalent specification, telling specifyModel to add paths for\n# variances and covariance of RGenAsp and FGenAsp:\n\nmodel.dhp <- specifyModel(covs=\"RGenAsp, FGenAsp\")\nRParAsp -> RGenAsp, gam11\nRIQ -> RGenAsp, gam12\nRSES -> RGenAsp, gam13\nFSES -> RGenAsp, gam14\nRSES -> FGenAsp, gam23\nFSES -> FGenAsp, gam24\nFIQ -> FGenAsp, gam25\nFParAsp -> FGenAsp, gam26\nFGenAsp -> RGenAsp, beta12\nRGenAsp -> FGenAsp, beta21\nRGenAsp -> ROccAsp, NA, 1\nRGenAsp -> REdAsp, lam21\nFGenAsp -> FOccAsp, NA, 1\nFGenAsp -> FEdAsp, lam42\n\nmodel.dhp\n\n# The same model in equation format:\n\nmodel.dhp.1 <- specifyEquations(covs=\"RGenAsp, FGenAsp\")\nRGenAsp = gam11*RParAsp + gam12*RIQ + gam13*RSES + gam14*FSES + beta12*RGenAsp + beta21*RGenAsp\nFGenAsp = gam23*RSES + gam24*FSES + gam25*FIQ + gam26*FParAsp + beta21*RGenAsp\nROccAsp = 1*RGenAsp\nREdAsp = lam21(1)*RGenAsp # to illustrate setting start values\nFOccAsp = 1*FGenAsp\nFEdAsp = lam42(1)*FGenAsp\n\nmodel.dhp\nclassifyVariables(model.dhp)\n\n# updating the model to impose equality constraints\n# and to rename the latent variables and gamma parameters\n\nmodel.dhp.eq <- update(model.dhp)\ndelete, RSES -> FGenAsp\ndelete, FSES -> FGenAsp\ndelete, FIQ -> FGenAsp\ndelete, FParAsp -> FGenAsp\ndelete, RGenAsp -> FGenAsp\nadd, RSES -> FGenAsp, gam14, NA\nadd, FSES -> FGenAsp, gam13, NA\nadd, FIQ -> FGenAsp, gam12, NA\nadd, FParAsp -> FGenAsp, gam26, NA\nadd, RGenAsp -> FGenAsp, beta12, NA\nreplace, gam, gamma\nreplace, Gen, General\n\nmodel.dhp.eq\n\n# A three-factor CFA model for the Thurstone mental-tests data,\n# specified three equivalent ways:\n\nR.thur <- readMoments(diag=FALSE,\n names=c('Sentences','Vocabulary','\n 'Letter.Series','Pedigrees','Letter.Group'))\n .828\n .776 .779\n .439 .493 .46\n .432 .464 .425 .674\n .447 .489 .443 .59 .541\n .447 .432 .401 .381 .402 .288\n .541 .537 .534 .35 .367 .32 .555\n .38 .358 .359 .424 .446 .325 .598 .452\n # (1a) in CFA format:\nmod.cfa.thur.c <- cfa(reference.indicators=FALSE)\nFA: Sentences, Vocabulary, Sent.Completion\nFC: Letter.Series, Pedigrees, Letter.Group\ncfa.thur.c <- sem(mod.cfa.thur.c, R.thur, 213)\nsummary(cfa.thur.c)\n # (1b) in CFA format, using reference indicators:\nmod.cfa.thur.r <- cfa()\nFA: Sentences, Vocabulary, Sent.Completion\nFC: Letter.Series, Pedigrees, Letter.Group\nspecifyModel\n\ncfa.thur.r <- sem(mod.cfa.thur.r, R.thur, 213)\nsummary(cfa.thur.r)\n\n# (2) in equation format:\n\nmod.cfa.thur.e <- specifyEquations(covs=\"F1, F2, F3\")\nSentences = lam11*F1\nVocabulary = lam21*F1\nSent.Completion = lam31*F1\nFirst.Letters = lam42*F2\n4.Letter.Words = lam52*F2\nSuffixes = lam62*F2\nLetter.Series = lam73*F3\nPedigrees = lam83*F3\nLetter.Group = lam93*F3\nV(F1) = 1\nV(F2) = 1\nV(F3) = 1\n\ncfa.thur.e <- sem(mod.cfa.thur.e, R.thur, 213)\nsummary(cfa.thur.e)\n\n# (3) in path format:\n\nmod.cfa.thur.p <- specifyModel(covs=\"F1, F2, F3\")\nF1 -> Sentences, lam11\nF1 -> Vocabulary, lam21\nF1 -> Sent.Completion, lam31\nF2 -> First.Letters, lam41\nF2 -> 4.Letter.Words, lam52\nF2 -> Suffixes, lam62\nF3 -> Letter.Series, lam73\nF3 -> Pedigrees, lam83\nF3 -> Letter.Group, lam93\nF1 <-> F1, NA, 1\nF2 <-> F2, NA, 1\nF3 <-> F3, NA, 1\n\ncfa.thur.p <- sem(mod.cfa.thur.p, R.thur, 213)\nsummary(cfa.thur.p)\n\n# The Thurstone CFA model with equality constraints on the\n# factor loadings and error variances\n\nmod.cfa.thur.ceq <- cfa(reference.indicators=FALSE)\nFA: Sentences = Vocabulary = Sent.Completion\nFC: Letter.Series = Pedigrees = Letter.Group\nvar: Sentences = Vocabulary = Sent.Completion\nvar: Letter.Series = Pedigrees = Letter.Group\ncfa.thur.ceq <- sem(mod.cfa.thur.ceq, R.thur, 213)\nsummary(cfa.thur.ceq)\nanova(cfa.thur.ceq)\npathDiagram(cfa.thur.ceq, ignore.double=FALSE, ignore.self=TRUE,\n min.rank=\"FA, FB, FC\", edge.labels=\"values\")\n\n# a multigroup CFA model fit to the Holzinger-Swineford\n# mental-tests data\nmod.hs <- cfa()\nspatial: visual, cubes, paper, flags\nverbal: general, paragrap, sentence, wordc, wordm\nmemory: wordr, numberr, figurer, object, numberf, figurew\nmath: deduct, numeric, problemr, series, arithmet\nmod.mg <- multigroupModel(mod.hs, groups=c(\"Female\", \"Male\"))\nsem.mg <- sem(mod.mg, data=HS.data, group=\"Gender\",\n formula = ~ visual + cubes + paper + flags +\n general + paragrap + sentence + wordc + wordm +\n wordr + numberr + figurer + object + numberf + figurew +\n deduct + numeric + problemr + series + arithmet)\nsummary(sem.mg)\n\n# with cross-group equality constraints:\nmod.mg.eq <- multigroupModel(mod.hs, groups=c(\"Female\", \"Male\"), allEqual=TRUE)\nsem.mg.eq <- sem(mod.mg.eq, data=HS.data, group=\"Gender\",\n formula = ~ visual + cubes + paper + flags +\n general + paragrap + sentence + wordc + wordm +\n wordr + numberr + figurer + object + numberf + figurew +\n deduct + numeric + problemr + series + arithmet)\nsummary(sem.mg.eq)\n\n## End(Not run)\n\n---\n\n### standardizedCoefficients\n\n**Standardized Coefficients for Structural Equation Models**\n\n**Description**\n\nThese functions calculate standardized regression coefficients for structural equation models. The function `stdCoef` is simply an abbreviation for `standardizedCoefficients`. \nUsage\n\nstandardizedCoefficients(object, ...) \n## S3 method for class 'sem' \nstandardizedCoefficients(object, \n digits = getOption(\"digits\"), oneheaded = TRUE, twoheaded = TRUE, ...) \n## S3 method for class 'msem' \nstandardizedCoefficients(object, ...) \nstdCoef(...) \n\nArguments\n\nobject an object of class sem or msem returned by the sem function.\ndigits number of digits for printed output.\noneheaded standardize path coefficients? Default is TRUE.\ntwoheaded standardize variances and covariances? Default is TRUE.\n... arguments to pass down.\n\nValue\n\nReturns a data frame with the coefficients, labelled both by parameter names and by arrows in the path diagram for the model. The msem (multigroup) method computes and prints the standardized coefficients for each group; it does not return a useful result.\n\nAuthor(s)\n\nJohn Fox <jfox@mcmaster.ca> and Adam Kramer\n\nReferences\n\n\nSee Also\n\nsem\n\nExamples\n\n# In the first example, readMoments() and specifyModel() read from the \n# input stream. This example cannot be executed via example() but can be entered \n# at the command prompt. The example is repeated using file input; \n# this example can be executed via example(). \n## Not run: \n# Duncan, Haller, and Portes peer-influences model \nR.DHP <- readMoments(diag=FALSE, names=c(\"ROccAsp\", \"REdAsp\", \"FOccAsp\", \n \"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\") \n .6247 \n .3269 .3669\nmodel.dhp <- specifyModel()\n\nRParAsp -> RGenAsp, gam11, NA\nRIQ -> RGenAsp, gam12, NA\nRSES -> RGenAsp, gam13, NA\nFSES -> RGenAsp, gam14, NA\nRSES -> FGenAsp, gam23, NA\nFSES -> FGenAsp, gam24, NA\nFIQ -> FGenAsp, gam25, NA\nFParAsp -> FGenAsp, gam26, NA\nFGenAsp -> RGenAsp, beta12, NA\nRGenAsp -> FGenAsp, beta21, NA\nRGenAsp -> ROccAsp, NA, 1\nRGenAsp -> REdAsp, lam21, NA\nFGenAsp -> FOccAsp, NA, 1\nFGenAsp -> FEdAsp, lam42, NA\nRGenAsp <-> RGenAsp, ps11, NA\nFGenAsp <-> FGenAsp, ps22, NA\nRGenAsp <-> FGenAsp, ps12, NA\nROccAsp <-> RGenAsp, theta1, NA\nREdAsp <-> REdAsp, theta2, NA\nFOccAsp <-> FOccAsp, theta3, NA\nFEdAsp <-> FEdAsp, theta4, NA\n\nsem.dhp <- sem(model.dhp, R.DHP, 329,\nfixed.x=c(\"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\"))\n\nstandardizedCoefficients(sem.dhp)\n\n# The following example can be executed via example():\n\netc <- system.file(package=\"sem\", \"etc\") # path to data and model files\n\n(R.DHP <- readMoments(file=file.path(etc, \"R-DHP.txt\"),\ndiag=FALSE, names=c(\"ROccAsp\", \"REdAsp\", \"FOccAsp\",\n\"FEdAsp\", \"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\")))\n\n(model.dhp <- specifyModel(file=file.path(etc, \"model-DHP.txt\")))\n\n(sem.dhp <- sem(model.dhp, R.DHP, 329,\nfixed.x=c(\"RParAsp\", \"RIQ\", \"RSES\", \"FSES\", \"FIQ\", \"FParAsp\")))\n\nstandardizedCoefficients(sem.dhp)\n**Description**\n\nThese data are from the SAS manual and consist of six mental tests for 32 students, with some missing data. The three x variables are intended to load on a verbal factor, and the three y variables on a math factor. The data can be used to illustrate the estimation of a confirmatory factor analysis model by multinormal full-information maximum-likelihood in the presence of missing data.\n\n**Usage**\n\nTests\n\n**Format**\n\nA data frame with 32 observations on the following 6 variables.\n\n- x1 score on verbal test 1.\n- x2 score on verbal test 2.\n- x3 score on verbal test 3.\n- y1 score on math test 1.\n- y2 score on math test 2.\n- y3 score on math test 3.\n\n**Source**\n\n\n---\n\n### Two-Stage Least Squares\n\n**Description**\n\nFits a regression equation, such as an equation in a structural-equation model, by two-stage least squares. This is equivalent to direct instrumental-variables estimation when the number of instruments is equal to the number of predictors.\n\n**Usage**\n\n```\n## S3 method for class 'formula'\ntsls(formula, instruments, data, subset, weights, na.action, contrasts=NULL, ...)\n## Default S3 method:\ntsls(y, X, Z, w, names=NULL, ...)\n## S3 method for class 'tols'\nprint(x, ...)\n## S3 method for class 'tols'\nsummary(object, digits=getOption(\"digits\"), ...)\n```\nArguments\n\n**formula** model formula for structural equation to be estimated; a regression constant is implied if not explicitly omitted.\n\n**instruments** one-sided model formula specifying instrumental variables.\n\n**data** an optional data frame containing the variables in the model. By default the variables are taken from the environment from which `tsls` is called.\n\n**subset** an optional vector specifying a subset of observations to be used in fitting the model.\n\n**weights, w** an optional vector of weights to be used in the fitting process; if specified should be a non-negative numeric vector with one entry for each observation, to be used to compute weighted 2SLS estimates.\n\n**na.action** a function that indicates what should happen when the data contain NAs. The default is set by the `na.action` option.\n\n**contrasts** an optional list. See the `contrasts.arg` argument of `model.matrix.default`.\n\n**y** Response-variable vector.\n\n**X** Matrix of predictors, including a constant (if one is in the model).\n\n**Z** Matrix of instrumental variables, including a constant (if one is in the model).\n\n**names** optional character vector of names for the columns of the X matrix.\n\n**x, object, model.2** objects of class `tsls` returned by `tsls.formula` (or of class `summary.tsls`), for anova containing nested models to be compared by an incremental $F$-test. One model should be nested in the other; the order of models is immaterial.\n\n**s2** an optional estimate of error variance for the denominator of the $F$-test. If missing, the error-variance estimate is taken from the larger model.\n\n**dfe** optional error degrees of freedom, to be specified when an estimate of error variance is given.\n\n**digits** number of digits for summary output.\n\n**...** arguments to be passed down.\nValue\ntls.formula returns an object of class tls, with the following components:\n\n- **n**: number of observations.\n- **p**: number of parameters.\n- **coefficients**: parameter estimates.\n- **V**: estimated covariance matrix of coefficients.\n- **s**: residual standard error.\n- **residuals**: vector of residuals.\n- **response**: vector of response values.\n- **X**: model matrix.\n- **Z**: instrumental-variables matrix.\n- **response.name**: name of response variable, or expression evaluating to response.\n- **formula**: model formula.\n- **instruments**: one-sided formula for instrumental variables.\n\nAuthor(s)\nJohn Fox <jfox@mcmaster.ca>\n\nReferences\n\nSee Also\nsem\n\nExamples\nsummary(tls(Q ~ P + D, ~ D + F + A, data=Kmenta)) # demand equation\nsummary(tls(Q ~ P + F + A, ~ D + F + A, data=Kmenta)) # supply equation\nanova(tls(Q ~ P + F + A, ~ D + F + A, data=Kmenta),\n tls(Q ~ 1, ~ D + F + A, data=Kmenta))\nIndex\n\n*Topic datasets\n Bollen, 2\n CNES, 7\n HS.data, 13\n Klein, 15\n Kmenta, 16\n Tests, 74\n\n*Topic dplot\n pathDiagram, 27\n\n*Topic htest\n bootSem, 3\n boot.ci, 4\n bootSem (sem-deprecated), 62\n\n*Topic manip\n fscores, 10\n rawMoments, 34\n readMoments, 36\n\n*Topic models\n bootSem, 3\n effects.sem, 8\n fscores, 10\n information.criteria, 14\n miSem, 17\n ML.methods, 19\n modIndices, 22\n objective.functions, 24\n optimizers, 26\n pathDiagram, 27\n ram, 33\n residuals.sem, 37\n sem, 40\n specifyModel, 63\n standardizedCoefficients, 72\n tsls, 75\n AIC.objectiveML (ML.methods), 19\n AIC.objectiveFIML (ML.methods), 19\n AIC.objectiveML, 19\n AICc.objectiveML (ML.methods), 19\n AICc.objectiveFIML (ML.methods), 19\n AICc.objectiveML (ML.methods), 19\n AICc.objectiveFIML (ML.methods), 19\n AICc.objectiveML, 19\n anova.msemObjectiveML (ML.methods), 19\n anova.objectiveFIML (ML.methods), 19\n anova.objectiveML (ML.methods), 19\n anova.tsls (tsls), 75\n BIC.msemObjectiveML (ML.methods), 19\n BIC.objectiveFIML (ML.methods), 19\n BIC.objectiveML (ML.methods), 19\n Bollen, 2\n boot, 5\n boot.ci, 4\n bootSem , 62\n CAIC (information.criteria), 14\n CAIC.objectiveFIML (ML.methods), 19\n CAIC.objectiveML, 14\n cfa, 17, 31, 40, 41, 44, 45, 48\n cfa (specifyModel), 63\n classifyVariables (specifyModel), 63\n CNES, 7\n coef.msem (sem), 40\n coef.sem (sem), 40\n coef.tsls (tsls), 75\n combineModels (specifyModel), 63\n complete, 18\n cor, 4\n cov, 4\n cov2raw (rawMoments), 34\n deviance.msemObjectiveML (ML.methods), 19\n deviance.objectiveFIML (ML.methods), 19\n deviance.objectiveML (ML.methods), 19\n df.residual.msem (sem), 40\n df.residual.sem (sem), 40\n edit.semmod (specifyModel), 63\n\n78\neffects.msem (effects.sem), 8\neffects.sem, 8\nfitted.tsls (tsls), 75\nfscores, 10\nGLS.methods (ML.methods), 19\nhetcor, 4\nHS.data, 12\ninformation.criteria, 14\nKlein, 15\nKmenta, 16\nlogLik.msemObjectiveML (ML.methods), 19\nlogLik.objectiveFIML (ML.methods), 19\nlogLik.objectiveML (ML.methods), 19\nMath (pathDiagram), 27\nmi, 17, 18\nmiSem, 17\nML.methods, 19\nmod.indices (sem-deprecated), 62\nmodel.matrix.default, 25, 76\nmodIndices, 22, 62\nmodIndices.objectiveML, 22\nmsemObjectiveGLS, 43\nmsemObjectiveGLS (objective.functions), 24\nmsemObjectiveML, 19, 43\nmsemObjectiveML (objective.functions), 24\nmsemObjectiveML2 (objective.functions), 24\nmsemOptimizerNlm, 43\nmsemOptimizerNlm (optimizers), 26\nmultigroupModel, 17, 40, 41\nmultigroupModel (specifyModel), 63\nnlm, 26, 27, 43, 48\nnlmnb, 26, 27, 43, 48\nnormalized.residuals (sem-deprecated), 62\nnormalizedResiduals, 62\nnormalizedResiduals (residuals.sem), 37\nobjective.functions, 22, 24, 26, 27\nobjectiveFIML, 18\nobjectiveFIML (objective.functions), 24\nobjectiveFIML2 (objective.functions), 24\nobjectiveGLS, 19, 26, 43, 48\nobjectiveGLS (objective.functions), 24\nobjectiveGLS2 (objective.functions), 24\nobjectiveML, 19, 26, 43, 44, 48\nobjectiveML (objective.functions), 24\nobjectiveML2 (objective.functions), 24\noptim, 26, 27, 43, 48\noptimizerMsem, 43\noptimizerMsem (optimizers), 26\noptimizerNlm, 48\noptimizerNlm (optimizers), 26\noptimizerNlmnb, 43, 48\noptimizerNlmnb (optimizers), 26\noptimizerOptim, 43, 48\noptimizerOptim (optimizers), 26\noptimizers, 24, 26, 26\noptimizerSem, 43\noptimizerSem (optimizers), 26\npath.diagram (sem-deprecated), 62\npathDiagram, 27, 62\nprint.bootsem (bootSem), 3\nprint.miSem (miSem), 17\nprint.modIndices (modIndices), 22\nprint.msemModIndices (modIndices), 22\nprint.msemObjectiveGLS (ML.methods), 19\nprint.msemObjectiveML (ML.methods), 19\nprint.objectiveFIML (ML.methods), 19\nprint.objectiveGLS (ML.methods), 19\nprint.objectiveML (ML.methods), 19\nprint.rawmoments (rawMoments), 34\nprint.semeffects (effects.sem), 8\nprint.semeffectsList (effects.sem), 8\nprint.semmod (specifyModel), 63\nprint.semmodList (specifyModel), 63\nprint.summary.bootsem (bootSem), 3\nprint.summary.objectiveML (ML.methods), 19\nprint.summary.tsls (tsls), 75\nprint.tsls (tsls), 75\nram, 33\nraw.moments (sem-deprecated), 62\nrawMoments, 34, 41, 48, 63\nread.moments (sem-deprecated), 62\nreadMoments, 36, 63\nremoveRedundantPaths (specifyModel), 63\nresiduals.msem (residuals.sem), 37\nresiduals.sem, 37\nresiduals.tsls (tsls), 75\n\nscale, 11\nsem, 3–5, 8, 11, 17–19, 21–27, 31, 34–36, 38, 40, 66, 67, 73, 77\nsem-deprecated, 62\nspecify.model (sem-deprecated), 62\nspecifyEquations, 17, 31, 40, 41, 44, 45, 48\nspecifyEquations (specifyModel), 63\nspecifyModel, 17, 31, 40, 41, 44, 45, 47, 48, 63, 63\nstandardized.coefficients\n (sem-deprecated), 62\nstandardized.residuals\n (sem-deprecated), 62\nstandardizedCoefficients, 63, 72\nstandardizedResiduals, 63\nstandardizedResiduals (residuals.sem), 37\nstartvalues, 48\nstartvalues (sem), 40\nstartvalues2 (sem), 40\nstd.coef (sem-deprecated), 62\nstdCoeff, 63\nstdCoeff (standardizedCoefficients), 72\nsummary.bootsem (bootSem), 3\nsummary.miSem (miSem), 17\nsummary.modIndices (modIndices), 22\nsummary.msemModIndices (modIndices), 22\nsummary.msemObjectiveGLS (ML.methods), 19\nsummary.msemObjectiveML (ML.methods), 19\nsummary.objectiveFIML (ML.methods), 19\nsummary.objectiveGLS (ML.methods), 19\nsummary.objectiveML (ML.methods), 19\nsummary.tsls (tsls), 75\n\nTests, 74\ntsls, 75\n\nupdate.semmod (specifyModel), 63\n\nvcov.msem (sem), 40\nvcov.sem (sem), 40\nvcov.tsls (tsls), 75"}}},{"rowIdx":78,"cells":{"id":{"kind":"string","value":"d5088f4012a5d6c11fd3710035780b63045ed526"},"text":{"kind":"string","value":"The SNOW Theorem Revisited\nKishori M Konwar, Wyatt Lloyd, Haonan Lu, Nancy Lynch\nNovember 27, 2018\n\nAbstract\n\nIn highly-scalable storage systems for Web services, data is sharded into separate objects, also called shards, across several servers. Transaction isolation, while reading the objects, is at the heart of consistent data access when concurrent updates are present. In practice, systems experience a much higher number of read transactions, consisting only of read operations, compared to write transactions; consequently, lowering latency of read transactions boosts service performance.\n\nIn [9], the authors proposed four desirable properties in transaction processing systems for achieving low-latency of read transactions, with asynchronous and reliable communications, and referred to them collectively as the SNOW properties: The underlying properties, in the context of an execution, are (i) strict serializability (S) property where read and write transactions seem to occur atomically; (ii) non-blocking (N) property implies that for every read operation on any object, during a read transaction, the response at the corresponding server is non-blocking; (iii) one version and one round (O) property implies every read operation, during a read transaction, completes in one-round of client-server communication and the respective server responds with only one version of the object value; and (iv) concurrent write transactions (W) property states that read transactions can have concurrent write transactions. Then they argued that it is impossible to implement all the four properties, in the same system, even with at least three clients. They referred to their result as the SNOW theorem, and they posed the two-client setting as an open question.\n\nHere we revisit the results of the SNOW theorem and present several new results. In our first result, we resolve the two-client scenario: We prove that even with two clients, without client-to-client messaging, it is impossible to design a transaction processing system which satisfies the SNOW properties. Second, we provide a rigorous proof of the SNOW theorem for systems with at least three clients, i.e., we show that it is impossible to implement a transaction processing system, consisting of at least three clients, even with client-to-client messaging, that satisfies the SNOW properties. In our third result, we derive a useful property for executions of algorithms that implement objects of data types considered in our work that helps us show the strict serializability property (S property) of algorithms presented in the paper.\n\nIn our fourth result, we present an algorithm with multiple writers, single reader (MWSR) which satisfies the SNOW properties, with client-to-client messaging. In our fifth, we present an algorithm, for multiple-writer, multiple-reader (MWMR) setting in the absence of client-to-client messaging, which satisfies the “S”, “N”, “W” properties and a weaker version the O property “o”, where we use “o” to refer to the one-version requirement of a read operation, but it can take multiple rounds of communication to complete a read operation. Collectively, we refer to the “S”, “N”, “o” and “W” properties as the “SNoW” property. In our sixth result, we present an algorithm in the MWMR setting which satisfies the “S”, “N”, “W” properties and a property “ɔ”, which refers to the one-round requirement of a read operation, but a server can response with multiple versions of a shard. We refer to these properties as the “SNoW” property.\n1 Introduction\n\nMost highly accessed websites rely on large volumes of data in the back end. Scalability of these websites is dependent on the ability to serve thousands of web-requests per second. Although it is desirable to store all of this data at a single server, due to limited resources available on a single machine it is impossible to do so. Therefore, such data is partitioned and stored across multiple machines connected through high-speed networks. Subsequently, serving one webpage request may involve retrieving various data objects of the page from multiple servers. These individual data objects are often referred to as shards or objects, where each object is managed by a separate server. For example, a dynamically generated webpage may contain various objects, such as texts, images, and videos: the text elements may be stored in one server, the images and thumbnails in another, and, similarly, the video clips may be managed by a separate server. During the webpage synthesis and loading, the proxy reader reads all of these separate objects via a read transaction. Some of these objects may be updated while read transactions are carried out. A transaction consists of a set of read or write operations on the underlying objects which are to be executed atomically.\n\nIn our work, we consider two types of transactions: write transactions and read transactions. A read transaction consists of a set of read operations, one per each object, and a write transaction comprises of a set of individual write operations on a subset of the objects. Consistent data access during a transactional read requires transactional isolation, where reads to different objects must retrieve either all updates for a given update or none. Similar transactional isolation of write transactions is also desirable, where the collection of all the write operations to different objects is carried out atomically. Handling transactional isolation with concurrent read and write transactions is complex and expensive which may often lead to poor performance and lower throughput, which in turn leads to substantial revenue loss and poor user experience. In practice, it is observed that most of the transactions are read transactions, and therefore, one approach to boost performance is to improve the performance of the read transactions [3].\n\nIn [9], the authors study the question whether read transactions can be fast enough even in the presence of concurrent write transactions. They introduce four desirable properties of a system to achieve low-latency read transactions, which they refer to collectively as the SNOW property: Strict serializability among transactions, Non-blocking operations and One-response from each shard for the read transactions, and compatibility with conflicting write transactions. The “strict serializability” property requires that the set of read or writer operations of any read and write transactions is executed atomically as if executed by a single server. “Non-blocking” requires the read requests corresponding to different objects to be served by the managing servers immediately, without blocking for any other external input or output messages. The “one-response” property requires that for any read operation of an object, the server managing the object responds with only one version, and the operation completes in one round of client to server communication. The final property “conflicting and concurrent write transactions” allows write transactions to execute concurrently with read transactions on the same set of objects.\n\nIn distributed systems, the availability of the systems is often stated in terms of liveness properties of the transactions or operations [5,6,12]. Such a requirement on responsiveness of a system is also referred to as availability. One of the strongest, and the most desirable of these properties is wait-freedom, which requires that as long as the client is taking a sufficient number of steps, it completes the operations irrespective of the speed of other clients. In [9], the wait-free property of the read operations, corresponding to a read transaction in a system that satisfies SNOW properties, is inherent in the N and O properties; this also implies the wait-freedom property for\nread transactions. However, in [9], no liveness property for write transactions is stated explicitly. In their work, the authors prove that with at least three clients, in an asynchronous message-passing environment, even in the absence of any failures, it is impossible to have a protocol that satisfies all of the four properties of SNOW, which they refer to as the SNOW theorem. In their proof, they consider a system with two read clients, which issues only read transactions, and a write client invoking write transactions. From their proof, it is not clear whether they consider the possibility of exchanging messages between clients. Additionally, there is no explicitly stated requirement on the liveness of the write transactions. They pose the case for two clients as an unresolved case, i.e., it is not known whether all of SNOW properties can be implemented for any two client system.\n\nOur contribution In this work, we revisit the results of the SNOW theorem and present four new results. First, we show that even with two clients, in the absence of client-to-client messaging, it is impossible to design a transaction processing system which satisfies the SNOW properties. Second, we provide a thorough proof of the SNOW theorem for systems with at least three clients, i.e., we show that it is impossible to implement a transaction processing system, which can implement the SNOW property, consisting of at least three clients, even with client-to-client messaging. In our proof, we explicitly make assumptions regarding the liveness of write transactions and client-to-client messaging. Our proof technique involves assuming an execution of an arbitrary transaction processing system, assumed to be specified as an I/O automaton, that satisfies the SNOW property, and then, argue by constructing a sequence of executions of the automata, finally, leading to an execution which contradicts the S property. The above two results indicate that client-to-client messaging ability plays a key role in the achievability of the SNOW property. This motivates our third result, where we present an algorithm with multiple writers, single reader (MWSR) which satisfies the SNOW properties when client-to-client messaging is allowed. Finally, we present an algorithm, for multiple-writer, multiple-reader (MWMR) setting in the absence of client-to-client messaging, which satisfies the “S”, “N”, “W” properties and and a weaker version the O property, which we denote by “o”, where “o” refers to the one-version property of a read operation, but can take multiple rounds of communication to complete the read operation. Collectively, we refer to the “S”, “N”, “o” and “W” properties as the “SNoW” property.\n\nRelated work This will be filled in depending what type of conference we send the paper to and whether we add some experimental results of the two algorithms presented in the paper.\n\nDocument Structure The remainder of the document is organized as follows. Section 2 presents the models and definitions. Section 3 provides the proof for the impossibility result for the two-client setting when clients do not communicate among each other. In section 4 we present the impossibility result for the three-client setting. Next, in section 6 we present the algorithm with multi-writer, single-reader (MWSR) which satisfies the SNOW properties, when client-to-client communication is allowed. In section 7 we present an algorithm for multi-writer, multi-reader scenario which satisfies the SNoW properties.\n2 System model and architecture\n\n2.1 I/O Automata\n\nWe consider a distributed system consisting of asynchronous processes of three types: a set of readers and writers, called clients, and a set of servers. Each of these processes is associated with an unique identifier. Processes can communicate via asynchronous reliable communication links. This means that any message sent on the link is guaranteed to eventually reach the destination process. The model assumes that client or server processes never fail. We do not make any assumption regarding the order of message delivery in the same channel.\n\nWe assume that the formal specification of an algorithm in our context is specified using the I/O Automata. An algorithm is specified from the composition $A$ of a set of automate $A_i$ where each automate $A_i$ corresponds to a process $i$ in the system. An automat $A_i$ consists of a set of states $states(A_i)$, including a special subset $start(A_i) \\subseteq states(A)$ called the start states; a signature, denoted $sig(A_i)$; and a set of transitions $trans(A_i)$. The set of states $states(A_i)$ are essentially defined by a set of state variables in $A_i$. The signature $sig(A_i)$ consists of three disjoint sets in $in(A_i)$, $out(A_i)$ and $int(A_i)$, where $in(A_i)$ referred to as the input actions, $out(A_i)$ the output actions and $int(A_i)$ are the internal actions. The set $trans(A_i)$ consists of the set of transitions or steps, where each step consists of a 3-tuple $(\\sigma_i, a_i, \\sigma_{i+1})$, where $\\sigma_i, \\sigma_{i+1} \\in states(A_i)$ and $a_i \\in trans(A_i)$. The set $in(A_i) \\cup out(A_i)$, often denoted as $ext(A_i)$, are called the external signature of automat $A_i$. Note that $A$ is a composition of the set of automata $A_i, i \\in I$ and the following analogous components for $A$ are defined as $states(A) = \\prod_{i \\in I} states(A_i)$; $sig(A) = \\prod_{i \\in I} sig(A_i)$; $start(A) = \\prod_{i \\in I} start(A_i)$ and $trans(A) = \\{ (\\sigma, a, \\sigma') : a \\in trans(A_i) \\text{ for some } i \\in I \\text{ then } \\sigma, \\sigma' \\in states(A_i), \\text{ else } \\sigma = \\sigma' \\}$.\n\nInformally, the execution of the algorithm corresponds to the concept of the execution of $A$. First, an execution fragment $\\alpha$ of $A$ is a finite or infinite sequence $\\sigma_0, a_1, \\sigma_1, a_2, \\sigma_2, \\ldots$, where each $\\sigma_i$ belong to $states(A)$ and $a_i$ belongs to $trans(A)$. An execution of $A$ is an execution fragment such that $\\sigma_0 \\in start(A)$. We use the notation $trace(\\alpha)$ to denote the sequence of external actions in $\\alpha$; and by $trace(\\alpha)|A_i$ to denote the sequence of external actions in $trace(\\alpha)$ that belongs to automat $A_i$. If $\\alpha$ is a finite execution and $\\beta$ is an execution fragment, such that, $\\beta$ starts with the final state of $\\alpha$ then we use the symbol $\\alpha \\circ \\beta$ to denote execution fragment obtained as a result of concatenation of execution fragments $\\alpha$ and $\\beta$. The set of locally controller actions in an automat can be partitioned into tasks. Moreover, in the case of an execution, if the execution is infinite and events from each class occurs infinitely often, and if the execution is finite and if none of the events from any of the classes is enabled then the execution is called fair. If $\\epsilon$ and $\\epsilon'$ are two execution fragments such that at some automat $A$ they are the same, i.e., $\\epsilon | A = \\epsilon' | A$, then we use the notation $\\epsilon \\sim \\epsilon'$. When the automat is clear from the context, for the sake of brevity we drop the symbol for the automat over the $\\sim$. Below we add some useful theorems are useful related to executions of a composed I/O Automata \\cite{10}.\n\n**Theorem 2.1.** Let $\\{A_i\\}_{i \\in I}$ be a compatible collection of automata and let $A = \\Pi_{i \\in I} A_i$. Suppose $\\alpha_i$ is an execution of $A_i$ for every $i \\in I$, and suppose $\\beta$ is a sequence of actions in $ext(A)$ such that $\\beta | A_i = trace(\\alpha_i)$ for every $i \\in I$. Then there is an execution $\\alpha$ of $A$ such that $\\beta = trace(\\alpha)$ and $\\alpha_i = \\alpha | A_i$ for every $i \\in I$.\n\n**Theorem 2.2.** Let $A$ be any I/O automaton.\n\n1. If $\\alpha$ is a finite execution of $A$, then there is a fair execution of $A$ that starts with $\\alpha$. \n\n\n2. If $\\beta$ is a finite trace of $A$, then there is a fair trace of $A$ that starts with $\\beta$.\n\n3. If $\\alpha$ is a finite execution of $A$ and $\\beta$ is any finite or infinite sequence of input actions of $A$, then there is a fair execution $\\alpha \\circ \\alpha'$ of $A$ such that the sequence of input actions in $\\alpha'$ is exactly $\\beta$.\n\n4. If $\\beta$ is a finite trace of $A$ and $\\beta'$ is any finite or infinite sequence of input actions of $A$, then there is a fair execution $\\alpha \\circ \\alpha'$ of $A$ such that $\\text{trace}(\\alpha) = \\beta$ and such that the sequence of input actions in $\\alpha'$ is exactly $\\beta'$.\n\nThe following useful claim is adopted from Chapter 16 of [10].\n\n**Claim 1.** Suppose we have an automaton $A = \\Pi_{i=1}^k A_i$ where $A$ is composed of the compatible collection of automata $A_i$, where $i \\in \\{1, \\ldots, k\\}$. Let $\\beta$ be a fair trace of $A$ then we define an irreflexive partial order $\\beta$ on the actions of $\\beta$ as follows. If $\\pi$ and $\\phi$ are events in $\\beta$, with $\\pi$ preceding $\\phi$, then we say $\\phi$ depends on $\\pi$, which we denote as $\\pi \\rightarrow_\\beta \\phi$, if one of the following holds:\n\n1. $\\pi$ and $\\phi$ are actions at the same automaton;\n2. $\\pi$ is some $\\text{send}(\\cdot)_{ij}$ at some $A_j$ and $\\phi$ is some $\\text{recv}(\\cdot)_{ji}$ at $A_i$; and\n3. $\\pi$ and $\\phi$ are related by a chain of the relations of items 1. and 2.\n\nThen if $\\gamma$ is a sequence obtained by reordering the events in $\\beta$ while preserving the $\\rightarrow_\\beta$, then $\\gamma$ is also a fair trace of $A$.\n\n**Theorem 2.3.** Let $\\{A_i\\}_{i \\in I}$ be a compatible collection of automata and let $A = \\Pi_{i=1}^k A_i$. Suppose $\\alpha_i$ is a fair execution of $A_i$ for every $i \\in I$, and suppose $\\beta$ is a sequence of actions in $\\text{ext}(A)$ such that $\\beta|A_i = \\text{trace}(\\alpha_i)$ for every $i \\in I$. Then there is a fair execution $\\alpha$ of $A$ such that $\\beta = \\text{trace}(\\alpha)$ and $\\alpha_i = \\alpha|A$ for every $i \\in I$.\n\n### 2.2 Data type\n\nIn this section, we formally describe the data type, which we denote as $O_T$, for the transaction processing systems considered in this paper. We assume there is a set of $k$ objects, where $k$ is some positive integer, and $o_k$ denotes the $k^{th}$ object. Object $o_k$ stores a value from some non-empty domain $V_k$ and supports two types of operations: $\\text{read}$ and $\\text{write}$ operations. A read operation on object $o_k$, denoted by $\\text{read}(o_k)$, on completion returns the value stored in $o_k$. A write operation on $o_k$ with some value $v_k$ from $V_k$, denoted as $\\text{write}(o_k, v_k)$, on completion, updates the value of $o_k$.\n\nA write transaction consists of a subset of $p$ distinct write operations for a subset of $p$ distinct objects, where $1 \\leq p \\leq k$. For example, a write transaction with the set of operations \\{write($o_{i_1}, v_{i_1}$), write($o_{i_2}, v_{i_2}$)\\ldots write($o_{i_p}, v_{i_p}$)}}, means value $v_{i_1}$ is to be written to object $o_{i_1}$, value $v_{i_2}$ to object $o_{i_2}$, and so on. We denote such a write transaction as $\\text{WRITE}((o_{i_1}, v_{i_1}), (o_{i_2}, v_{i_2}), \\ldots, (o_{i_p}, v_{i_p}))$.\n\nA read transaction consisting of a set of read operations is denoted as $\\text{READ}(o_{i_1}, o_{i_2}, \\ldots, o_{i_q})$, where $o_{i_1}, o_{i_2}, \\ldots, o_{i_q}$ is a set of distinct objects, $q$ is any positive integer, $1 \\leq q \\leq k$, which upon completion returns the values ($v_{i_1}, v_{i_2}, \\ldots, v_{i_q}$), where $v_{i_j} \\in V_{i_j}$ is the value returned by $\\text{read}(o_{i_j})$, for any $i_j \\in \\{i_1, i_2, \\ldots, i_q\\}$ and $1 \\leq i_1 < i_2 < \\ldots < i_q \\leq k$.\n\nFormally, we define the value type used in this paper for a $k$ object data-type as follows:\n(i) a tuple \\((v_1, v_2, \\cdots, v_k) \\in \\Pi_{i=1}^k V_i\\), where \\(V_i\\) is a domain of values, for each \\(i \\in \\{1, \\cdots, k\\}\\);\n\n(ii) an initial value \\(v_i^0, v_i^0 \\in V_i\\) for each object \\(o_i\\);\n\n(iii) *invocations*: \\(READ(o_{i_1}, o_{i_2}, \\cdots, o_{i_p})\\) and \\(WRITE((o_{i_1}, v_{i_1}), (o_{i_2}, v_{i_2}), \\cdots, (o_{i_p}, v_{i_p}))\\), such that \\(v_{i_j} \\in V_{i_j}\\) for any \\(i_j \\in \\{i_1, i_2, \\cdots, i_p\\}\\) where \\(1 \\leq i_1 < i_2 < \\cdots < i_p \\leq k\\) and \\(p\\) is some integer with \\(1 \\leq p \\leq k\\);\n\n(iv) *responses*: a tuple \\((v_1, v_2, \\cdots, v_k) \\in \\Pi_{i=1}^k V_i\\) and \\(ok\\); and\n\n(v) for any subset of \\(p\\) objects we define \\(f : \\text{invocations} \\times V \\rightarrow \\text{responses} \\times V\\), such that:\n\n(a) \\(f(READ(o_{i_1}, o_{i_2}, \\cdots, o_{i_p}), (v_1, v_2, \\cdots, v_k)) = ((v_1, v_2, \\cdots, v_k), (v_1, v_2, \\cdots, v_k))\\);\n\n(b) \\(f(WRITE((o_{i_1}, u_{i_1}), (o_{i_2}, u_{i_2}), \\cdots, (o_{i_p}, u_{i_p})), (v_1, v_2, \\cdots, v_k)) = (ack, (w_1, w_2, \\cdots, w_k))\\),\n\nwhere for any \\(i, w_i = u_i\\) if \\(i \\in \\{i_1, i_2, \\cdots, i_p\\}\\), and for all other values of \\(i, w_i = v_i\\).\n\nFigure 1: The architecture of a typical web service with clients and servers inside a datacenter.\n\n2.3 System Model\n\nIn our system, we assume there are \\(\\ell\\) writers, for some \\(\\ell \\geq 1\\); \\(m\\) readers, for some \\(m \\geq 1\\), and \\(k\\) servers for some \\(k \\geq 1\\). We denote the set of writers as \\(W\\), which essentially consists of the writer identifiers \\(w_1, w_2, \\cdots, w_\\ell\\). The set of readers, with ids \\(r_1, r_2, \\cdots, r_m\\), is denoted as \\(R\\). The set of servers \\(S\\) consists of the server identifiers \\(s_1, s_2, \\cdots, s_k\\). The servers \\(s_1, s_2, \\cdots, s_k\\) manage the objects \\(o_1, o_2, \\cdots, o_k\\), respectively, in particular, server \\(s_i\\) is responsible for storing object \\(o_i\\), for any \\(i\\), \\(1 \\leq i \\leq k\\).\nCommunications between processes during the executions are point-to-point and are assumed to be reliable and asynchronous. The communications are modeled with Channel I/O automata and are carried out via send and recv actions at the source and destination processes. For example, in Figure 2, the reader \\( r_1 \\) automaton sends, via the action send\\((m)\\), some message \\( m \\), from some alphabet \\( M \\), to server \\( s_1 \\) through the channel automaton Channel\\( r_1, s_1 \\), and \\( s_1 \\) receives it through the action recv\\((m)\\). Similarly, the message \\( m', m' \\in M \\), is transmitted from \\( s_1 \\) to \\( r_1 \\), through the channel automaton Channel\\( s_1, r_1 \\), via the actions send\\((m')\\) at \\( s_1 \\), and finally received at \\( r_1 \\) via the action recv\\((m')\\).\n\nThe schematic flow of a typical, but simplified, webpage request from a service hosted in a datacenter is shown in Figure 1. An end user sends a webpage request to a front-end client \\( r_1 \\). Upon receiving it \\( r_1 \\) generates a read transaction \\( R \\), which consists of a set of read operations and is invoked via a INV\\((R)\\) action at the client, which is essentially input to the client from the end user. The goal of these operations is to read a subset of the data objects by contacting the respective managing servers. The operations in a transaction are carried out between the invocation and response actions of the transaction without any particular order of execution among the operations. Any operation \\( op \\) begins with an invocation action, \\( inv(op) \\), at the relevant client, and ends with a response action \\( resp(op) \\), also at the client. Once the front-end client completes the read operations, then \\( r_1 \\) synthesizes the webpage with the data retrieved by the read operations, and responds to the end user request through the response action RESP\\((R)\\) at the client \\( r_1 \\). Similarly, the update request from the end user can be thought of a write transaction \\( W \\), consisting of a set of write\n\n\\[1\\] In a typical production system the depth of the transactions (due to nested transactions) is more than one [1], however, we assume only transactions of depth one as in [9].\noperations for individual objects, to update the set of object values, initiated via an invocation action $INV(W)$ at the client. Then the writes operations are carried out by the client, and once they complete, the transaction completes with the response action $RESP(W)$, at the client.\n\nA transaction $\\pi$ is incomplete in an execution $\\alpha$ when the action $INV(\\pi)$ does not have the $RESP(\\pi)$ in $\\alpha$; otherwise, we say that $\\pi$ is complete in $\\alpha$. In an execution, we say that a transaction (read or write) $\\pi_1$ precedes another transaction $\\pi_2$ (denote as $\\pi_1 \\rightarrow \\pi_2$), if the response action $RESP(\\pi_1)$ precedes the invocation action $INV(\\pi_2)$. Two transactions are concurrent if neither precedes the other.\n\nIf in any execution of the system every client initiates a new transaction only after the previous transactions initiated at the same client have completed, then we say the execution is well-formed.\n\n### 2.4 SNOW Properties\n\nThe SNOW properties for a transaction processing system can be described by requiring that any fair execution of the system satisfies the following four properties: (i) **Strict Serializability** (S), which means there is a total ordering of the transactions such that the resulting execution seems to occur at a single machine atomically; (ii) **Non-Blocking Operations** (N) property, which means that the servers respond immediately, without waiting for any input from other processes, to read requests for the read operations, which belong to the READ transactions; (iii) **One Response Per Read** (O) property requires that any read operation consists of one-round trip of communication with a server, and also, the server responds with a message that contains exactly one version of the object value; and (iv) WRITE transactions that Conflict (W) implies the existence of concurrent WRITE transactions that update the data objects while READ transactions are in progress. Below we describe the individual properties of the SNOW properties in more detail.\n\n**Strict serializability** By strict serializability [7], we mean each WRITE or READ transaction is executed atomically, at some point in an execution between the invocation and response events. In other words, for each transaction, we can associate a serialization point between the invocation and response actions, such that all the read operations return values that are consistent with the ordering of the serialization points.\n\n**Non-blocking reads** Consider a READ transaction initiated by a read client $r$ and a read operation in it to read the value of an object $o_i$ managed by some server $s_i$. The read operation involves $r$ communicating a send value message to $s_i$ requesting the stored value of $o_i$. The non-blocking property means that the server responds to the read request without waiting for any external input event, such as the arrival of messages, any mutex operations, time, etc. This property ensures that READ transactions are delayed only due to delay of messages between $r$ and $s_i$. Below we define the non-blocking nature of any server’s response to a read request from a reader as follows.\n\n**Definition 1.** If $\\alpha$ is a fair execution of some server automaton for a server $s$ and action $recv(m^r)_{r,s}$ appears in $\\alpha$, where $r$ is a reader automaton and $m^r$ is a read value request to server $s$, and no other input actions follow $recv(m^r)_{r,s}$, then eventually, the action $send(v_i)_{s,r}$ occurs in $\\alpha$.\n\n**One-response read operations** The one-response property requires that each read operation, during any READ transaction, completes in one round of client to server communication and receives exactly one version of the object value from the corresponding server. A round consists of a read\nrequest from the client initiating the read operation to the server, and subsequently, the server sending only one version of the object value in its response. The one-round property is imposed to reduce the number of messages between the client and the server during a read operation, and hence reducing the latency of the READ transaction. The one-version property is added to reduce the amount of data transmitted during the read operation and hence reduce latency of read operations, which also means lowering latency for the READ transaction.\n\n**Concurrent and conflicting writes** The conflicting, or concurrent writes property states that read transactions complete even in the presence of concurrent write transactions, where the write operations might update some objects that are also being read by read operations in read. This shows that read transactions can be invoked at any point, even in the presence of ongoing write transactions. Note that the liveness of any write transaction is not implied by any of the SNOW properties; however, for useful practical systems the writes must eventually complete. Therefore, we assume that every write transaction eventually completes via the RESP event, and think of this constraint as a part of the W property.\n\n**The SNOW Theorem** The theorem states that no read-only transaction algorithm provides all of the SNOW properties.\n\n### 2.5 One-version property\n\nMotivated by the impossibility result of the SNOW theorem, we propose in Section 7 an algorithm for transaction processing systems under constraints weaker than the SNOW properties. With this in mind, we introduce a weaker version of the O property, denote it as “o”, where during a read operation the server returns exactly one object value but there exists a finite bound on the number of rounds of communication between the client and the server. We use the acronym SNoW to denote the S, N, o and W properties. Moreover, it is easy to realize that if an algorithm satisfies the SNoW properties then READ transactions always complete, and hence, READ’s are always live. This is because the N and o properties imply that the server must immediately respond to a read request due to a read operation with exactly one object value without waiting in expectation of incoming messages, and there a fixed upper bound on the number of such rounds for a READ.\n\n### 3 Impossibility of SNOW properties with two clients with restricted communication\n\nIn this section, we prove that for a two-client transaction processing system with at least two objects it is impossible to design an algorithm that satisfies the SNOW properties. We prove our result by showing a contradiction. For the model consider in this section, we assume that between every pair of client and server, or every pair of servers there are two communication channels, one in each direction; however, there are no communication channels between any pair of clients Fig 2.\n\nConsider a system consisting of two servers, \\( s_1 \\) and \\( s_2 \\), and two clients, a reader \\( r \\), which initiates only read transactions, and a writer \\( w \\), which initiates only write transactions. Servers \\( s_1 \\) and \\( s_2 \\) store values for objects \\( o_1 \\) and \\( o_2 \\), respectively. The values stored in \\( o_1 \\) and \\( o_2 \\) belong to the domains \\( V_1 \\) and \\( V_2 \\), respectively; the initial values of \\( o_1 \\) and \\( o_2 \\) are \\( v_0^1 \\) and \\( v_0^2 \\), respectively. We denote the automata for servers \\( s_1 \\) and \\( s_2 \\) by \\( s_1^A \\) and \\( s_2^A \\), respectively, and the automata for the\nclients \\( r \\) and \\( w \\) by \\( r^A \\) and \\( w^A \\), respectively. We denote by \\( S_1 \\) the subsystem consisting of \\( s_1, \\) \\( s_2 \\) and \\( w, \\) and by \\( S_1^A \\) the automata composed of \\( s_1^A, \\) \\( s_2^A \\) and \\( w^A, \\) i.e., \\( s_1^A \\times s_2^A \\times w^A. \\) Also, we denote by \\( \\mathcal{A}, \\) which can also be interpreted as the algorithm, the automaton representing the entire system consisting of \\( S_1^A \\) and \\( r^A \\) (i.e., \\( s_1^A \\times s_2^A \\times w^A \\times r^A)). \\) We assume that between any client \\( c, \\) \\( c \\in \\{ r, w \\} \\) and any server \\( s, \\) \\( s \\in \\{ s_1, s_2 \\} \\) there are channel automata \\( Channel_{c, s} \\) and \\( Channel_{s, c}. \\) Here, we consider only fair executions of \\( \\mathcal{A}. \\) For contradiction, we also assume that any fair execution of \\( \\mathcal{A} \\) respects the SNOW properties. Also, we assume that in an execution \\( \\epsilon \\) of \\( \\mathcal{A} \\) we can identify each transaction with an unique identifier.\n\nConsider an execution of \\( \\mathcal{A} \\) with two transactions in it as: a \\textsc{write} transaction \\( W \\equiv WRITE((o_1,v_1^1),(o_2,v_2^1)) \\) initiated by \\( w, \\) where \\( v_1^1 \\neq v_0^1 \\) and \\( v_2^1 \\neq v_0^2; \\) and a \\textsc{read} transaction \\( R \\equiv READ(o_1,o_2), \\) initiated by \\( r. \\) Let us denote by \\( op_1^r \\) and \\( op_2^r \\) the read operations \\( \\text{read}(o_1) \\) and \\( \\text{read}(o_2), \\) respectively. We assume that the patterns of sequences of invocations of transaction, the times of these invocations, and delays in local computation and message deliveries, are controlled by an omniscient entity, which we refer to as the adversary. The assumption of such an adversary is in accordance with the asynchronous nature of the model. This is also important in real systems, because such executions are possible to occur and thus important for making the system safe.\n\n**Notations and Definitions:** We introduce the following notations and definitions in the context of an execution \\( \\epsilon \\) of \\( \\mathcal{A}, \\) with transactions \\( R \\) and \\( W \\) in it, where \\( j \\in \\{1,2\\}: \\)\n\n1. \\( \\text{send}(m_j^r)_{r,s_j}: \\) an output action at \\( r^A, \\) which sends a message \\( m_j^r \\) from \\( r \\) to \\( s_j, \\) requesting the value for \\( o_j; \\)\n2. \\( \\text{recv}(m_j^r)_{s_j,r}: \\) an input action at \\( s_j^A, \\) that receives the message \\( m_j^r, \\) sent from \\( r; \\)\n3. \\( \\text{send}(v_j)_{s_j,r}: \\) an output action at \\( s_j^A, \\) that sends value \\( v_j, \\) for \\( o_j, \\) to \\( r. \\)\n4. \\( \\text{recv}(v_j)_{s_j,r}: \\) an input action at \\( r^A, \\) to receive a message \\( v_j \\) from \\( s_j \\) at \\( r^A. \\)\n5. Non-blocking fragments \\( F_i(\\epsilon), \\) \\( i \\in \\{1,2\\}. \\) Suppose there is a fragment of execution in \\( \\epsilon \\) where the first action is \\( \\text{recv}(m_j^r)_{r,s_j} \\) and the last action is \\( \\text{send}(v_i)_{s_i,r} \\) of which occur at \\( s_i^A. \\) Moreover, suppose there is no other input action at \\( s_i^A \\) in this fragment. Then we call this execution fragment a non-blocking response fragment for \\( op_i^r \\) at \\( s_i^A. \\) We use the notation \\( F_i(\\epsilon) \\) to denote this fragment of execution of \\( \\epsilon. \\)\n6. We use the notations \\( R(\\epsilon) \\) and \\( W(\\epsilon) \\) to denote the transactions \\( R \\) and \\( W, \\) in \\( \\epsilon. \\) When the underlying execution is clear from the context we simply use \\( R \\) and \\( W. \\)\n7. If the non-blocking fragment \\( F_i(\\epsilon) \\) appears in \\( \\epsilon \\) such that \\( \\text{recv}(m_j^r)_{r,s_2}, \\) at \\( s_2^A, \\) does not occur before \\( F_i(\\epsilon) \\) completes and \\( \\epsilon \\) is of the form \\( \\sigma_0, a_1, \\ldots, a_\\ell, \\sigma_\\ell \\circ F_1(\\epsilon) \\circ S(\\epsilon), \\) where \\( S(\\epsilon) \\) is any continuation of the execution, then we denote \\( \\sigma_0, a_1, \\ldots, a_\\ell, \\sigma_\\ell \\) by \\( P(\\epsilon). \\)\n8. If \\( \\epsilon \\) is of the form \\( \\sigma_0, a_1, \\ldots, a_\\ell, \\sigma_\\ell \\circ F_1(\\epsilon) \\circ \\kappa \\circ F_2(\\epsilon) \\circ \\sigma_p, \\ldots \\) or \\( \\sigma_0, a_1, \\ldots, a_\\ell, \\sigma_\\ell \\circ F_2(\\epsilon) \\circ \\kappa \\circ F_1(\\epsilon) \\circ S(\\epsilon), \\) where \\( \\ell \\) is a positive integer, \\( \\kappa \\) is a segment of \\( \\epsilon, \\) possibly even of length zero and \\( S(\\epsilon) \\) is any suffix part of the execution then we denote \\( \\sigma_0, a_1, \\ldots, a_\\ell, \\sigma_\\ell \\) by \\( P(\\epsilon). \\) Clearly, we can write \\( \\epsilon \\) as \\( P(\\epsilon) \\circ F_1(\\epsilon) \\circ \\kappa \\circ F_2(\\epsilon) \\circ S(\\epsilon) \\) or \\( P(\\epsilon) \\circ F_2(\\epsilon) \\circ \\kappa \\circ F_1(\\epsilon) \\circ S(\\epsilon). \\)\nNow we describe the set of actions corresponding to the read operations in a fair execution $\\varepsilon$ of $A$. Clearly, in $\\varepsilon$, the actions $inv(op^r_i)$ and $resp(op^r_i)$ appear between the actions $INV(R)$ and $RESP(R)$. The action $inv(op^r_i)$ is followed by action $send(m^r_i)_{r,s_i}$, which is for sending the read object value request to server $s_i$. This request $m^r_i$ is communicated to $s_i$, via the channel automaton $Channel_{s_i}$. Automaton $s^A_i$ eventually receives the request via the action $recv(m^r_i)_{r,s_i}$, and subsequently, responds back to $r$, with object value $v_i$, through the action $send(v_i)_{s_i,r}$. Next, value $v_i$, $v_i \\in V$, is communicated by the automaton $Channel_{s_i,r}$, is received at $r$ via the action $recv(v_i)_{s_i,r}$, and finally, $op^r_i$ completes with response action $resp(op^r_i)$ and returns $v_i$ to $r^A$.\n\nHere, we give a high-level idea of our proof, which is based on the existence of a sequence of fair executions of $A$, eventually leading to a fair execution of $A$ that contradicts the S property. First, we show the existence of an execution $\\alpha$ of $A$ where $R$ is invoked after $W$ completes, where the send actions $send(m^r_1)_{r,s_1}$ and $send(m^r_2)_{r,s_2}$ at the $r^A$, occur consecutively, in $P(\\alpha)$. Then we show $\\alpha$ can be written in the form $P(\\alpha) \\circ F_1(\\alpha)$ (Figure 3 (a), Lemma 3.1). Based on $\\alpha$, we show the existence of another execution $\\beta$, of $A$, which can be written in the form $P(\\beta) \\circ F_1(\\beta) \\circ F_2(\\beta)$, by extending $\\alpha$ with an execution fragment $F_2(\\beta)$ such that, $F_1(\\beta) \\lesssim F_1(\\alpha)$ (Figure 3 (b); Lemma 3.2). Note that in any arbitrary extension (as a fair execution) of $\\beta$, eventually $R$ returns $(v_1^r, v_2^r)$. Next, from $\\beta$, we show the existence of an execution $\\gamma$, of $A$, of the form $P(\\gamma) \\circ F_1(\\gamma) \\circ F_2(\\gamma)$, where the send actions $send(m^r_1)_{r,s_1}$ and $send(m^r_2)_{r,s_2}$ at $r^A$, occur before $W$ is invoked (Figure 3 (c); Lemma 3.3), but the fragments $F_1(\\gamma)$ and $F_2(\\gamma)$ occur after $RESP(W)$, as in $\\beta$. From $\\gamma$ we show the existence of a fair execution $\\delta$, of $A$, of the form $P(\\eta) \\circ F_1(\\eta) \\circ F_2(\\eta) \\circ S(\\eta)$, where $R$ responds with $(v_1^r, v_2^r)$. Finally, starting with $\\eta$ we create a sequence of fair executions $\\delta(\\equiv \\eta)$, $\\delta^{(1)}$, $\\cdots$ $\\delta^{(l)}$, of $A$, where in each of them $R$ responds with $(v_1^r, v_2^r)$ (Figure 4 (c) and (g); Lemma 3.6). Additionally, for any $\\delta^{(i)}$, the fragments $F_1(\\delta^{(i)})$ and $F_2(\\delta^{(i)})$ appear in the execution before $\\delta^{(i-1)}$. From $\\delta^{(l)}$ we show the existence of a fair execution $\\phi$ (see Figure 4 (h)), of $A$, where $R$ completes by returning $(v_1^r, v_2^r)$ even before $W$ begins, which is violation of the property $S$.\n\nNow, we state and prove the the relevant lemmas. The following lemma states that there is a finite execution of $A$ where $R$ begins after $W$ completes where the two send actions $send(m^r_1)_{r,s_1}$ and $send(m^r_2)_{r,s_2}$ occur before either of the servers $s_1$ and $s_2$ receives the messages $m^r_1$ or $m^r_2$ from $r$; also, server $s_1$ responds to $r$ in a non-blocking manner (execution $\\alpha$ in Figure 2 (a)).\n\n**Lemma 3.1.** There exists a finite execution $\\alpha$ of $A$ that contains transactions $R(\\alpha)$ and $W(\\alpha)$ where $INV(R)$ appears after $RESP(W)$ and the following conditions hold:\n\n(i) The actions $send(m^r_1)_{r,s_1}$ and $send(m^r_2)_{r,s_2}$ appear consecutively in trace($\\alpha$)$|r^A$; and\n\n(ii) $\\alpha$ contains the execution fragment $F_1(\\alpha)$.\n\n**Proof.** Consider a finite execution fragment of $A$ with a completed transaction $W$, where after $W$ completes the adversary invokes $R$, i.e., $INV(R)$ occurs. Note that each of the read operations $op^r_i$ and $op^r_j$ in $R$, can be invoked by the adversary at any point in the execution. Following $INV(R)$, the adversary introduces the invocation action $inv(op^r_i)$; by the O property of the read operations of $A$ the action $send(m^r_i)_{r,s_1}$ eventually occurs. Next, the adversary introduces $inv(op^r_j)$ and also, delays the arrival of $m^r_i$ until action $send(m^r_j)_{r,s_2}$ eventually occurs, which must occur in accordance with the property $O$ of read operations. Let us call this finite execution $\\alpha^0$.\n\nNext, suppose at the end of $\\alpha^0$ the adversary delivers the message $m^r_i$, which has been delayed so far, via the action $recv(m^r_i)_{r,s_1}$, at $s^A_i$, but it delays any other input actions at $s^A_i$. Note that by the $N$ property of read operations $s^A_i$ eventually responds with $send(v_1)_{s_1,r}$, with one value $v_1$ by\nO property, where \\( v_1 = v_1^1 \\) by the S property, since \\( R \\) begins after \\( W \\) completes. Let us call this execution \\( \\alpha \\). Note that \\( \\alpha \\) satisfies conditions (i) and (ii) by the design of the execution. \\( \\square \\)\n\nThe following lemma states that there is an execution \\( \\beta \\) of \\( A \\) where \\( R \\) begins after \\( W \\) completes where the two send events at \\( r^A \\) occurs before \\( F_1(\\beta) \\), which in turn, occurs before \\( F_2(\\beta) \\) (execution \\( \\beta \\) in Figure 3 (b)).\n\n**Lemma 3.2.** There exists an execution \\( \\beta \\) of \\( A \\) that contains transactions \\( R \\) and \\( W \\) where INV(\\( R \\)) appears after RESP(\\( W \\)) and the following conditions hold:\n\n(i) The actions send\\((m_1^1)_{r,s_1}\\) and send\\((m_2^r)_{r,s_2}\\) appear consecutively in trace(\\( \\beta \\)|\\( r^A \\)); and\n\n(ii) \\( \\beta \\) contains the execution fragment \\( F_1(\\beta) \\circ F_2(\\beta) \\).\n\n**Proof.** Consider the execution \\( \\alpha \\) of \\( A \\) as constructed in Lemma \\ref{lem:alpha}. At the end of the execution fragment \\( \\alpha \\), the adversary delivers the previously delayed message \\( m_2^r \\), which is sent via the action send\\((m_1^1)_{r,s_1}\\) and send\\((m_2^r)_{r,s_2}\\). The adversary then delivers any other input action in \\( A \\). By the N property, server \\( s_2^A \\) must respond to \\( r^A \\), with some value \\( v_2 \\), and hence the output action send\\((v_2)_{s_2,r}\\) must eventually occur at \\( s_2^A \\). Let us call this finite execution as \\( \\beta \\). Note that \\( \\beta \\) satisfies the properties (i) and (ii) in the statement of the lemma. \\( \\square \\)\n\nThe following result shows that starting with \\( \\beta \\) there is an execution \\( \\gamma \\) of \\( A \\) where \\( R \\) is initiated before \\( W \\) is initiated, also, the send events send\\((m_1^1)_{r,s_1}\\) and send\\((m_2^r)_{r,s_2}\\) occur before INV(\\( W \\)) (execution Figure 3 (c)) and the messages \\( m_1^1 \\) and \\( m_2^r \\) from \\( r^A \\) reach the servers \\( s_1 \\) and \\( s_2 \\), respectively, after the action RESP(\\( W \\)).\n\n**Lemma 3.3.** There exists a fair execution \\( \\gamma \\) of \\( A \\) with transactions \\( R \\) and \\( W \\) where the action INV(\\( R \\)) appears before INV(\\( W \\)) and RESP(\\( R \\)) appears after RESP(\\( W \\)), and the following conditions hold for \\( \\gamma \\):\n\n(i) The actions send\\((m_1^1)_{r,s_1}\\) and send\\((m_2^r)_{r,s_2}\\) appear before INV(\\( W \\)) and they appear consecutively in trace\\((\\gamma)\\)|\\( r^A \\);\n\n(ii) \\( \\gamma \\) contains the execution fragment \\( F_1(\\gamma) \\circ F_2(\\gamma) \\); and\n\n(iii) action RESP(\\( W \\)) occurs before \\( F_1(\\gamma) \\).\n\n**Proof.** Consider the execution \\( \\beta \\) of \\( A \\) as in Lemma \\ref{lem:beta}. Note that \\( \\beta \\) is an execution of the composed automaton \\( A \\equiv S_1^A \\times r^A \\). In \\( \\beta \\), the actions send\\((m_1^1)_{r,s_1}\\) and send\\((m_2^r)_{r,s_2}\\) occur at \\( r^A \\); and following that, the actions recv\\((m_1^1)_{r,s_1}\\), recv\\((m_2^r)_{r,s_2}\\), send\\((v_1)_{s_1,r}\\) and send\\((v_2)_{s_2,r}\\) occur at \\( S_1^A \\). Consider the executions \\( \\alpha_r \\equiv \\beta|\\( r^A \\) and \\( \\alpha_{S_1} \\equiv \\beta|\\( S_1^A \\). Let \\( s_\\beta \\) denote trace\\((\\beta)\\).\n\nIn \\( s_\\beta \\), send\\((m_1^1)_{r,s_1}\\), send\\((m_2^r)_{r,s_2}\\) appear after RESP(\\( W \\)), as in trace\\((\\beta)\\). Let \\( s_\\beta' \\) be the sequence of external actions of \\( S_2^A \\) which we construct from \\( s_\\beta \\) by moving send\\((m_1^1)_{r,s_1}\\), send\\((m_2^r)_{r,s_2}\\) before INV(\\( W \\)), which is also an external action of \\( A \\), and leaving the rest of the actions in \\( s_\\beta \\) as it is.\n\nIn \\( \\beta \\), INV(\\( R \\)), recv\\((v_1)_{s_1,r}\\) and recv\\((v_2)_{s_2,r}\\) are the only input actions at \\( r^A \\), therefore, \\( s_\\beta'|\\( r^A \\) = trace(\\( \\alpha_r \\)). On the other hand, recv\\((m_1^1)_{r,s_1}\\), recv\\((m_2^r)_{r,s_2}\\) are the only input actions at \\( S_1^A \\), therefore, \\( s_\\beta'|\\( S_1^A \\) = trace(\\( \\alpha_{S_1} \\)). Now, by Theorem \\ref{thm:gamma} there exists an execution \\( \\gamma \\) of \\( A \\) such that, \\( s_\\beta' = trace(\\gamma) \\) and \\( \\alpha_r \\gamma|\\( r^A \\) and \\( \\alpha_{S_1} = \\gamma|\\( S_1^A \\). Therefore, in \\( \\gamma \\), send\\((m_1^1)_{r,s_1}\\), send\\((m_2^r)_{r,s_2}\\) appear before INV(\\( W \\)) (condition (ii)) and since \\( s_\\beta' = trace(\\gamma) \\) condition (ii) holds. Conditions (iii) holds trivially. \\( \\square \\)\nIn the following lemma we show that in any fair execution, of \\( A \\), that is an extension of either execution \\( \\beta \\) or execution \\( \\gamma \\), as in the preceding lemmas, \\( R \\) eventually returns \\( (v_1^1, v_2^1) \\).\n\n**Lemma 3.4.** Let \\( \\xi \\) be a fair execution of \\( A \\) that is an extension of the either execution \\( \\beta \\) from Lemma 3.2 or execution \\( \\gamma \\) from Lemma 3.3, then \\( R(\\xi) \\) responds with \\( (v_1^1, v_2^1) \\).\n\n**Proof.** Note that in executions \\( \\beta \\) and \\( \\gamma \\), the traces \\( \\text{trace}(\\beta)|s_1^1 \\) is a prefix of \\( \\text{trace}(\\gamma)|s_1^A \\), since \\( \\beta \\) ends with \\( F_1(\\beta) \\) and \\( \\gamma \\) ends with \\( F_2(\\gamma) \\). Therefore, in both \\( \\beta \\) and \\( \\gamma \\), the respective \\( \\text{send}(v_1)_{s_{1,r}} \\) actions have the same value for their \\( v_1 \\)'s. Now, in any extended fair execution \\( \\eta \\) of \\( A \\), which starts with \\( \\beta \\) or \\( \\gamma \\), by the properties \\( N \\) and \\( O \\) the transaction \\( R \\) completes; and by the property \\( S \\), \\( R \\) returns \\( (v_1^1, v_2^1) \\). Therefore, \\( R(\\xi) \\) returns \\( (v_1^1, v_2^1) \\). \\( \\square \\)\n\nIn the following lemma, we show there exists an execution \\( \\eta \\) of \\( A \\) of the form \\( P(\\eta) \\circ F_1(\\eta) \\circ F_2(\\eta) \\circ S(\\eta) \\) where \\( R \\) eventually returns \\( (v_1^1, v_2^1) \\).\n\n**Lemma 3.5.** There exists a fair execution \\( \\eta \\) of \\( A \\) that contains transactions \\( R \\) and \\( W \\) where \\( \\text{INV}(R) \\) appears before \\( \\text{INV}(W) \\); \\( \\text{RESP}(R) \\) appears after \\( \\text{RESP}(W) \\) and the following conditions hold for \\( \\eta \\):\n\n(i) \\( \\eta \\) can be written in the form \\( P(\\eta) \\circ F_1(\\eta) \\circ F_2(\\eta) \\circ S(\\eta) \\), for some \\( P(\\eta) \\) and \\( S(\\eta) \\);\n\n(ii) The actions \\( \\text{send}(m^1_{r,s_1}) \\) and \\( \\text{send}(m^2_{r,s_2}) \\) appear before \\( \\text{INV}(W) \\) and they appear consecutively in \\( \\text{trace}(\\eta)_{r^A} \\);\n\n(iii) action \\( \\text{RESP}(W) \\) occurs before \\( F_1(\\eta) \\); and\n\n(iv) \\( R(\\eta) \\) returns \\( (v_1^1, v_2^1) \\).\n\n**Proof.** Let \\( \\gamma \\) be a fair execution of \\( A \\), as described in Lemma 3.3. Let \\( \\gamma^0 \\) be the execution fragment of \\( \\gamma \\) up to the action \\( \\text{send}(v_2)_{s_{1,r}} \\). Now, by Theorem 2.2 (1), there exists a fair execution! \\( \\gamma^0 \\circ \\mu \\), of \\( A \\), where \\( \\mu \\) denotes the extended portion of the execution.\n\nClearly, by the \\( N \\) and \\( O \\) properties, the actions \\( \\text{resp}(\\text{op}_1^r) \\) and \\( \\text{resp}(\\text{op}_2^r) \\) must eventually occur in \\( \\gamma^0 \\circ \\mu \\). Now, identify \\( \\eta \\) as \\( \\gamma^0 \\circ \\mu \\), where \\( P(\\eta) \\circ F_1(\\eta) \\circ F_2(\\eta) \\) is \\( \\gamma^0 \\), and \\( \\mu \\) is \\( S(\\eta) \\), thereby, proving condition (i).\n\nNote that the condition (ii) is satisfied by \\( \\eta \\) because \\( \\text{RESP}(W) \\) appears in \\( P(\\eta) \\), therefore, the fair execution \\( \\gamma \\) is equivalent to the execution fragment of \\( P(\\eta) \\) up to the event \\( \\text{INV}(W) \\), and also, \\( \\gamma \\) satisfies condition (ii) as stated in Lemma 3.3.\n\nCondition (iii) is true because \\( F_1(\\eta) \\) begins with action \\( \\text{recv}(m^1_{r,s_1}) \\), which occurs after \\( \\text{resp}(W) \\). Condition (iv) is satisfied by \\( \\eta \\) because \\( \\eta \\) is an extension of \\( \\gamma \\) and due to the result of Lemma 3.4. \\( \\square \\)\n\nIn the following theorem we prove the impossibility result for achieving the SNOW properties for the two-client system by starting with a fair execution \\( \\eta \\) and creating a sequence of fair executions of \\( A \\), where each one is of the form \\( P(\\cdot) \\circ F_1(\\cdot) \\circ F_2(\\cdot) \\circ S(\\cdot) \\), with progressively shorter \\( P(\\cdot) \\) until one of them contradicts the property \\( S \\).\n\n**Theorem 3.6.** The SNOW properties cannot be implemented in a system with two clients and two servers, where the clients do not communicate with other clients.\nFigure 3: Schematic representation of executions α, β, γ and η, of A with transactions R and W. The executions evolve from left to right. The vertical marks denote external events at the reader and the server automata. The marks above the horizontal line denote external actions at \\( s_A^1 \\), and the marks below the line for external actions at \\( s_A^2 \\), and for actions \\( r^A \\) the mark cuts through the line. The dots stand for other external actions at the individual automata.\n\nProof. Consider a fair execution \\( \\delta^{(\\ell)} \\) of A as in Lemma 3.5, and let \\( P(\\delta^{(\\ell)}) \\) be the execution fragment \\( \\sigma_0, a_1, \\ldots, a_\\ell, \\sigma_\\ell \\), where \\( \\ell \\) is some positive integer, and the \\( \\sigma_i \\)'s and \\( a_i \\)'s denote states and actions, respectively. By Lemma 3.5, \\( \\text{RESP}(R(\\delta^{(\\ell)})) \\) returns \\( (v_0^1, v_0^2) \\) and \\( \\delta^{(\\ell)} \\) is also of the form \\( \\sigma_0, a_1, \\ldots, a_\\ell, \\sigma_\\ell \\circ F_1(\\delta^{(\\ell)}) \\circ F_2(\\delta^{(\\ell)}) \\circ S(\\delta^{(\\ell)}) \\).\n\nNow, inductively we prove the existence of a finite sequence of fair executions of A—by proving the existence of one from the previous one—as \\( \\delta^{(\\ell)} \\), \\( \\delta^{(\\ell-1)} \\), \\( \\ldots \\), \\( \\delta^{(i)} \\), \\( \\delta^{(i-1)} \\), \\( \\ldots \\), \\( \\delta^{(f)} \\), for some positive integer \\( f \\), with the following properties: (a) Each of the execution in the sequence can be written in the form \\( \\sigma_0, a_1, \\ldots, a_i, \\sigma_i \\circ F_1(\\delta^{(i)}) \\circ F_2(\\delta^{(i)}) \\circ S(\\delta^{(i)}) \\) (or \\( P(\\cdot) \\circ F_1(\\cdot) \\circ F_2(\\cdot) \\circ S(\\cdot) \\)); (b) for each \\( i, f \\leq i < \\ell \\) we have \\( P(\\delta^{(i)}) \\) is a prefix of \\( P(\\delta^{(i+1)}) \\); and (c) \\( R(\\delta^{(f)}) \\) returns \\( (v_0^1, v_0^2) \\) and for any \\( i, f < i \\leq \\ell \\) we have \\( R(\\delta^{(i)}) \\) returns \\( (v_1^1, v_1^2) \\). Note that there is a final execution of the form \\( \\delta^{(f)} \\) because of the initial values of \\( v_0^1 \\) and \\( v_0^2 \\), and the WRITE W.\n\nClearly, there exists an integer \\( k, f \\leq k < \\ell \\) such that \\( R(\\delta^{(k)}) \\) returns \\( (v_0^1, v_0^2) \\) and \\( R(\\delta^{(k+1)}) \\)\nreturns \\((v_1^1, v_2^1)\\). Now we start with execution \\(\\delta^{(k+1)}\\) and construct an execution \\(\\delta^{(k)}\\) as described in the rest of the proof. The following argument will show that \\(R(\\delta^{(k)})\\) must also return \\((v_1^1, v_2^1)\\) thereby contradicting the above.\n\nConsider the fair execution \\(\\delta^{(k+1)}\\) of \\(A\\) which is of the form \\(\\sigma_0, a_1, \\sigma_1, \\ldots, a_{k+1}, \\sigma_{k+1} \\circ F_1(\\delta^{(k+1)}) \\circ F_2(\\delta^{(k+1)}) \\circ S(\\delta^{(k+1)})\\). The action \\(a_{k+1}\\) can occur at any of the automata \\(r^A, w^A, s_1^A\\) or \\(s_2^A\\), therefore, we prove our claim by considering the following four possible cases.\n\n**Case (i) \\(a_{k+1}\\) occurs at \\(w^A\\):** The execution fragments \\(F_1(\\delta^{(k+1)})\\) and \\(F_2(\\delta^{(k+1)})\\) do not contain any input action at \\(s_1^A\\) and \\(s_2^A\\), respectively, and also, \\(a_{k+1}\\) does not occur at \\(s_1^A\\) or \\(s_2^A\\). Hence, the adversary can delay the occurrence of action \\(a_{k+1}\\), at \\(w^A\\), to create the finite execution \\(\\sigma_0, a_1, \\cdot, a_k, \\sigma_k \\circ F_1(\\delta^{(k+1)}) \\circ F_2(\\delta^{(k+1)})\\), of \\(A\\). Note by Theorem 2.2 (1), there exists a fair execution \\(\\delta^{(k)}\\), of \\(A\\), that is an extension of the above finite execution where, by the liveness property of a READ transaction, \\(R\\) completes in \\(\\delta^{(k)}\\). Clearly, \\(\\delta^{(k)}\\) can be written as \\(\\sigma_0, a_1, \\cdot, a_k, \\sigma_k \\circ F_1(\\delta^{(k)}) \\circ F_2(\\delta^{(k)}) \\circ S(\\delta^{(k)})\\), where \\(S(\\delta^{(k)})\\) is the tail part of the execution resulting from the extension. At \\(s_1^A\\), \\(F_1(\\delta^{(k+1)})\\) is indistinguishable from \\(F_1(\\delta^{(k)})\\) i.e., \\(F_1(\\delta^{(k+1)}) \\sim F_1(\\delta^{(k)})\\). Therefore, in both of the above fragments, the \\(send(v_1)_{s_1,r}\\) action has the same object value \\(v_1\\). But this means \\(R\\) returns \\(v_1^1\\) as the value for \\(o_1\\) and hence, by the property \\(S\\), \\(R(\\delta^{(k)})\\) must respond with \\((v_1^1, v_2^1)\\).\n\n---\n\n\\(^2\\)We drop the superscript \\(A\\), such as \\(s_1^A\\), to \\(s_1\\), from the symbol above \\(~\\) for formatting reasons, when necessary.\nCase (ii) $a_{k+1}$ occurs at $r^A$: Similar to Case (i).\n\nCase (iii) $a_{k+1}$ occurs at $s^A$: Observe that the execution fragments $a_{k+1}\\sigma_{k+1} \\circ F_1(\\delta^{(k+1)})$ and $F_2(\\delta^{(k+1)})$ occur at separate automata, i.e., at $s^A_1$ and $s^A_2$, respectively. Observe that the execution fragments $a_{k+1}\\sigma_{k+1} \\circ F_1(\\delta^{(k+1)})$ and $F_2(\\delta^{(k+1)})$, of $A$, do not contain any input actions at $s^A_1$ and $s^A_2$, respectively. Therefore, by Claim 1 we can create a fair execution $e$, of $A$, which can be expressed as $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_2(e) \\circ a_{k+1}, \\sigma_{k+1} \\circ F_1(e) \\circ S(e)$. Clearly, $F_1(e) \\cong F_1(\\delta^{(k+1)})$ and $F_2(e) \\cong F_2(\\delta^{(k+1)})$. Now, since action $send(v_1)_{s_1,r}$, in both $F_1(e)$ and $F_1(\\delta^{(k+1)})$, sends the same object value $v_1^1$ to $r$. Therefore, $R$ returns $(v_1^1, v_1^2)$.\n\nNow let us denote the execution fragment $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_2(e)$ by $e'$, which is simply a finite prefix of $e$. Now, suppose the adversary appends the $recv(m_1^r)_{r,s_1}$ to $e'$, i.e., delivers the value request message from $r$ to $s_1$, and creates a finite execution $e''$, of $A$, as $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_2(e''), recv(m_1^r)_{r,s_1}$, and delays any input action at $s^A_2$. Now, by Theorem 2.2 (1), there exists a fair execution $e'''$ of $A$, which extends $e''$. Clearly, $F_2(e''') \\cong F_2(e'')$ and hence the $send(v_2)_{s_2,r}$ actions in $e''$ and $e'''$, send the same value $v_2^1$ for $s_2$. Then by the N property action $send(v_1)_{s_1,r}$ eventually occurs and by O property $v_1$ is send to $r^A$, therefore, $R$ completes in $e'''$, this would imply that $R(e''')$ must respond with $(v_1^1, v_2^1)$.\n\nNote that the execution fragment of $e'''$, between the actions $recv(m_1^r)_{r,s_1}$ and $send(v_1)_{s_1,r}$, has no input actions of $s^A_1$, which can be identified as $F_1(e''')$. Therefore, $e'''$ can be written as $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_2(e'') \\circ F_1(e''') \\circ S(e''')$.\n\nNext, since $F_1(e''')$ and $F_2(e''')$ contains actions of two separate automata, therefore, by Claim 1 we can create an execution prefix $e^{(iv)}$ as $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_1(e^{(iv)}) \\circ F_2(e^{(iv)})$, where $F_1(e^{(iv)})$ appears before $F_2(e^{(iv)})$. Next by using Theorem 2.2 (1) we create fair execution $\\delta^{(k)}$ as an extension of $e^{(iv)}$. Clearly, it can be written as $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_1(\\delta^{(k)}) \\circ F_2(\\delta^{(k)}) \\circ S(\\delta^{(k)})$. Then by O and N properties $R$ completes in $\\delta^{(k)}$. Since $F_1(e^{(iv)}) \\cong F_1(e^{(iv)})$ this implies action $send(v_1)_{s_1,r}$ sends $v_1^1$ for object $o_1$ in $e^{(iv)}$ and since $F_1(\\delta^{(k)}) \\cong F_1(e^{(iv)})$, this implies action $send(v_1)_{s_1,r}$ sends $v_1^1$ in $\\delta^{(k)}$, this would imply that $R(\\delta^{(k)})$ returns $(v_1^1, v_2^1)$.\n\nCase (iv) $a_{k+1}$ occur at $s^A$: Since $a_{k+1}$ occurs at $s^A_1$ and $F_1(\\delta^{(k+1)})$ occurs at $s^A_1$, (i.e., separate automata), then by applying Claim 1 as in the previous cases we can create a new fair execution $e$ of $A$ (Figure 4 (f)) as $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_1(e) \\circ a_{k+1}, \\sigma_{k+1} \\circ F_2(e) \\circ S(e)$ such that, $F_1(e) \\cong F_1(\\delta^{(k+1)})$ where $a_{k+1}, \\sigma_{k+1} \\circ F_1(e) \\circ a_{k+1}, \\sigma_{k+1} \\circ F_2(e) \\circ S(e)\\circ F_1(\\delta^{(k+1)})$ and $R(e)$ returns $(v_1^1, v_2^1)$.\n\nNow, consider the finite execution $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_1(e)$ for $A$ and suppose the adversary appends the $recv(m_2^r)_{r,s_2}$ to create a finite execution of $A$ as $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_1(e), recv(m_2^r)_{r,s_2}$. Now, by Theorem 2.2 (1), there exists a fair execution $e'$ of $A$, where the adversary delays the input actions at $s^A_2$. By $N$ and $O$ properties $send(v_2)_{s_2,r}$ occurs in $e'$. Clearly, since $F_1(e') \\cong F_1(e)$ the $send(v_1)_{s_1,r}$ actions, in $e$ and $e'$, send the same value for $o_1$. Therefore, $R$ responds with $(v_1^1, v_2^1)$, where $v_2 \\in V_2$.\n\nNow, in $e'$, we identify the fragment which begins with $recv(m_2^r)_{r,s_2}$ and end with the action $send(v_2)_{s_2,r}$ as $F_2(e')$ to write $e'$ as $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_1(e') \\circ F_2(e')$. Now using Theorem 2.2 (1), we know there exists a fair execution $\\delta^{(k)}$ of $A$, which is an extension of $e'$. Clearly, $\\delta^{(k)}$ can be written as $\\sigma_0, a_1, \\ldots, a_k, \\sigma_k \\circ F_1(\\delta^{(k)}) \\circ F_2(\\delta^{(k)}) \\circ S(\\delta^{(k)})$, where $S(\\delta^{(k)})$ is the tail part of the extended fair execution. Clearly, $F_1(\\delta^{(k)}) \\cong F_1(e')$; therefore, $R(\\delta^{(k)})$ returns $v_1^1$ for object $o_1$, in $\\delta^{(k)}$ and this implies $R(\\delta^{(k)})$ must return $(v_1^1, v_2^1)$.\nFigure 5: The architecture of a typical web service with clients, servers, and the communication channels, between every pair of processes, inside a datacenter is modeled as a collection of I/O automata. Note that, unlike the architecture in Fig. 2 in this setup there are communication channels between every pair of clients.\n\n4 Impossibility of SNOW properties with three clients\n\nIn this section, we prove that for a three-client transaction processing system, with at least two objects, it is impossible to design an algorithm that satisfies the SNOW properties. From the proof of the SNOW Theorem [9], it is not clear whether a write transaction is ever required to complete in the presence of ongoing read transactions (Fig. 5). Moreover, the authors in [9] do not state explicitly whether the result of the SNOW Theorem holds if clients communicate with each other. In our proof, we state these points explicitly: each write must complete even if there are concurrent read transactions, and between every pair of processes, there are two communication channels, one in each direction (Fig 5). Furthermore, we assume that if a read is invoked at a reader, then the reader can proceed to contact the servers without waiting for any incoming messages.\n\nWe prove our result by showing a contradiction. We consider a system consisting of two servers, $s_1$ and $s_2$, and three clients: two readers $r_1$ and $r_2$, which initiate only read transactions, and a writer $w$, which initiates only write transactions. Servers $s_1$ and $s_2$ store values for objects $o_1$ and $o_2$, respectively; the values in $o_1$ and $o_2$ belong to the domains $V_1$ and $V_2$, respectively; the initial values of $o_1$ and $o_2$ are $v_1^0$ and $v_2^0$, respectively. We denote the automata for servers $s_1$ and $s_2$ by $s_1^A$ and $s_2^A$, respectively, and the automata for the clients $r_1$, $r_2$ and $w$ by $r_1^A$, $r_2^A$ and $w^A$, respectively. We assume that between any pair of processes $p_1$ and $p_2$, such that $p_1 \\neq p_2$, there are channel automata $Channel_{p_1,p_2}$ and $Channel_{p_2,p_1}$. For the purpose of proving by contradiction, we also assume that any fair execution of $B$ respects the SNOW properties. Also, we assume that in any execution of $B$ we can identify each transaction with a unique identifier.\nConsider an execution of $B$ with three transactions: a write transaction $W \\equiv WRITE((o_1,v_1^1),(o_2,v_2^1))$ initiated by $w$, where $v_1^1 \\neq v_1^0$ and $v_2^1 \\neq v_2^0$; and read transactions $R_1 \\equiv READ(o_1,o_2)$ and $R_2 \\equiv READ(o_1,o_2)$ initiated by $r_1$ and $r_2$, respectively. Let us denote by $op_1^r$ and $op_2^r$ the read operations of types $read(o_1)$ and $read(o_2)$, respectively. As in Section 3, we assume an omniscient adversary that can control the patterns of sequences of invocations of transactions, the times of these invocations, and delays in local computation and message deliveries. In the rest of the section, in order to reduce notational clutter, for any execution of $B$, $\\sigma_0,a_1,\\cdots,a_k,\\sigma_k\\cdots$, where $\\sigma$’s and $a$’s are states and actions, we use the notation $a_1,\\cdots,a_k\\cdots$ that shows only the actions while leaving out the states.\n\n**Notations and Definitions:** We introduce the following notations and definitions in the context of a fair execution $\\alpha$, of $B$, with transactions $R$ and $W$ in it, where $j \\in \\{1,2\\}$:\n\n1. $send(m_j^r)_{r,s_j}$: an output action at $r^A$, which sends a message $m_j^r$ from reader $r$ to server $s_j$, requesting the value for $o_j$;\n\n2. $recv(m_j^r)_{r,s_j}$: an input action at $s_j^A$, that receives the message $m_j^r$, sent from $r$;\n\n3. $send(v_j)_{s_j,r}$: an output action at $s_j^A$, that sends value $v_j$, for $o_j$, to $r$.\n\n4. $recv(v_j)_{s_j,r}$: an input action at $r^A$, to receive a message $v_j$ from $s_j$ at $r^A$.\n\n5. **Non-blocking fragments** $F_j(\\alpha)^{(v_j)}$, $j \\in \\{1,2\\}$. Suppose there is a fragment of execution in $\\alpha$ where the first action is $recv(m_j^r)_{r,s_i}$ and the last action is $send(v_j)_{s_i,r}$, both of which occur at $s_i^A$. Moreover, suppose there is no other input action at $s_i^A$ in this fragment. Then we call this execution fragment a non-blocking response fragment for $op_i^r$ at $s_i^A$. We use the notation $F_i(\\alpha)^{(v_j)}$ to denote this fragment of execution of $\\alpha$ (Fig. 6). In the context of a read $R_i$, for $i \\in \\{1,2\\}$, we use the notation $F_{i,j}(\\alpha)^{(v_j)}$ to denote $F_j(\\alpha)^{(v_j)}$.\n\n6. Suppose read $R$ completes in $\\alpha$. Consider the execution fragment in $\\alpha$ between the event $INV(R)$ and whichever of the events $send(m_2^r)_{r,s_2}$ and $send(m_1^r)_{r,s_1}$ that occurs later. If all the actions in this fragment correspond to $r^A$, then we denote this fragment as $I(\\alpha)$ (Fig. 6). In case of a read $R_i$, for $i \\in \\{1,2\\}$, we use the notation $I_i(\\alpha)$ for $I(\\alpha)$.\n\n7. Suppose reads $R$ completes in $\\alpha$. Consider the execution fragments in $\\alpha$ that occurs between the later of the events $recv(v_1)_{s_1,r}$ or $recv(v_2)_{s_2,r}$, i.e., at the point in $\\alpha$ when $r$ receives responses from both the servers, and the event $RESP(R)$. If all the actions in this fragment occur at $r^A$, then we denote this fragment by $E(\\alpha)^{(v_1,v_2)}$, where $R$ returns the values $(v_1,v_2)$ (Fig. 6). In case of a read $R_i$, for $i \\in \\{1,2\\}$, we use the notation $E_i(\\alpha)^{(v_1,v_2)}$ for $E(\\alpha)^{(v_1,v_2)}$.\n\n8. We use the notations $R(\\alpha)$ and $W(\\alpha)$ to denote the transactions $R$ and $W$, in the context of $\\alpha$. When the underlying execution is clear from the context we simply use $R$ and $W$.\n\n9. For any $v_i^j \\in V_j$, the superscript $i$ corresponds to the version identifier, which uniquely identifies a version from a totally ordered set.\n\nAny read $R$ initiated at a reader $r$, via the invocation action $INV(R)$ at $r$, after which the actions $send(m_1^r)_{r,s_1}$ and $send(m_2^r)_{r,s_2}$, at $r$, send message $m_1^r$ to $s_1$ and $m_2^r$ to $s_2$, respectively. Once $s_1$ receives $recv(m_1^r)_{r,s_1}$ then $s_1$ responds to $r$, in a non-blocking manner, with value $v_1$ via action...\nCorollary 1. Suppose $I$ fragment corresponds to the same version, i.e., $s_1 \\rightarrow i(t)$, $v_1 \\rightarrow i(t)$, and $s_2 \\rightarrow i(t)$, respectively. Then, $s_1$ sends the value $v_1$ to $i(t)$, which is received at $i(t)$ through the action $recv(v_1)_{i(t)}$. By the assumptions of the reliable channel automata in our model, we have $v_1 = v_2$, i.e., $t = t'$. Similar argument for $F_2(s_2)$ and $E(s_2)_{s_2}$ leads us to conclude $s = s'$. Next, $R$ responds with $(v_1', v_2')$, which implies by the S property for executions of $B$ that $v_1'$ and $v_2'$ must correspond to the same version, i.e., $s' = t'$.\n\nNote that the above results hold even if there are any other execution fragments, that do not contain any actions at $r$, $s_1$ or $s_2$, in-between the $I$, $F_1$ and $E$ execution fragments.\n\nCorollary 1. Suppose $\\alpha$ is any execution of $B$ such that a READ $R$ is in $\\alpha$. Suppose the execution fragment $I(\\alpha) \\circ F_1(\\alpha)(v_1') \\circ F_2(\\alpha)(v_2') \\circ E(\\alpha)(v'_1, v'_2)$ in $\\alpha$, corresponds to $R$, where $v_1', v_2' \\in V_1$ and $v_2', v_2' \\in V_2$, and $s, s', t, t'$ are version identifiers then (i) $s = s'$ and $t = t'$ and (ii) $s' = t'$.\n\nProof. Suppose $R$ is invoked at reader $r$. Then, via the action $send(v_1)_{s_1}$, in execution fragment $F_1(\\alpha)(v_1')$, server $s_1$ sends the value $v_1'$ to $r$, which is received at $r$ through the action $recv(v_1')_{s_1}$ in $E(\\alpha)(v'_1, v'_2)$. By the assumptions of the reliable channel automata in our model, we have $v_1' = v_2'$, i.e., $t = t'$. Similar argument for $F_2(\\alpha)(v_2')$ and $E(\\alpha)(v'_1, v'_2)$ leads us to conclude $s = s'$. Next, $R$ responds with $(v_1', v_2')$, which implies by the S property for executions of $B$ that $v_1'$ and $v_2'$ must correspond to the same version, i.e., $s' = t'$. □\n\\(v'_1, v''_1 \\in V_1 \\text{ and } v'_2, v''_2 \\in V_2, X_1, X_2, X_3 \\) are some execution fragments that do not contain any action at \\(r\\), \\(s_1\\) or \\(s_2\\), and \\(s, s', t, t'\\) are version identifiers then (i) \\(s = s'\\) and \\(t = t'\\) and (ii) \\(s' = t'\\).\n\nThe following lemma states that new fair executions of \\(B\\) can be created by swapping execution fragments that have no input actions, and in which each fragment contains actions that occur only at one automaton and the automata for the two fragments are different.\n\n**Lemma 4.2** (Commuting fragments). Let \\(\\alpha\\) be a fair execution of \\(B\\). Suppose \\(G_1(\\alpha)\\) and \\(G_2(\\alpha)\\) are any execution fragments in \\(\\alpha\\) such that all actions in each fragment occur only at one automaton and also, none of them are input actions. Suppose \\(G_1(\\alpha)\\) and \\(G_2(\\alpha)\\) occur at two distinct automata and the execution fragment \\(G_1(\\alpha) \\circ G_2(\\alpha)\\) occurs in \\(\\alpha\\). Then there exists a fair execution \\(\\alpha'\\) of \\(B\\), where the execution fragment \\(G_2(\\alpha) \\circ G_1(\\alpha)\\) appears in \\(\\alpha'\\), such that (i) the prefix in \\(\\alpha\\) before \\(G_1(\\alpha) \\circ G_2(\\alpha)\\) is identical to the prefix in \\(\\alpha'\\) before \\(G_1(\\alpha') \\circ G_2(\\alpha')\\); and (ii) the suffix in \\(\\alpha\\) after \\(G_1(\\alpha) \\circ G_2(\\alpha)\\) is identical to the suffix in \\(\\alpha'\\) after the execution fragment \\(G_2(\\alpha') \\circ G_1(\\alpha')\\).\n\n**Proof.** This is clear because the adversary can move the actions in \\(G_2\\) to occur before \\(G_1\\) at their respective automata, and these fragments do not contain any input actions, and hence the actions in one of these fragments cannot affect the actions in the other fragment. \\(\\square\\)\n\nThe following lemma states that if there are two fair executions of \\(B\\) with a READ \\(R\\) in each of them, and suppose at any server the non-blocking execution fragments of \\(R\\) are identical (in terms of the sequence of states and actions) then in both executions, \\(R\\) returns the same object value.\n\n**Lemma 4.3** (Indistinguishability). Let \\(\\alpha\\) and \\(\\beta\\) be executions of \\(B\\) and let \\(R\\) be any READ. Then (i) if \\(F_j(\\alpha) \\cong F_j(\\beta)\\) then both \\(R(\\alpha)\\) and \\(R(\\beta)\\) respond with the same value \\(v_1\\) for \\(o_1\\); and (ii) if \\(F_2(\\alpha) \\cong F_2(\\beta)\\) then both \\(R(\\alpha)\\) and \\(R(\\beta)\\) respond with the same value \\(v_2\\) for \\(o_2\\).\n\n**Proof.** Suppose \\(R\\) is invoked at some reader \\(r\\). Let \\(j \\in \\{1, 2\\}\\) and suppose the fragments \\(F_j(\\alpha)\\) and \\(F_j(\\beta)\\) appears in \\(\\alpha\\) and \\(\\beta\\) respectively, where in \\(F_j(\\alpha)\\) server \\(s_j\\) sends \\(v_j \\in V_j\\) to \\(r\\). Then \\(R(\\alpha)\\) must return \\(v_j\\) for object \\(o_j\\) by the \\(O\\) property of \\(B\\). Then since \\(F_j(\\alpha) \\cong F_j(\\beta)\\) then in \\(F_j(\\beta)\\) the server \\(s_j\\) must also send \\(v_j\\) to \\(r\\), therefore, both \\(R(\\alpha)\\) and \\(R(\\beta)\\) must return value \\(v_j\\) for \\(o_j\\). \\(\\square\\)\n\nBelow we show that in any finite execution of \\(B\\) where the final action is an invocation of READ \\(R\\) at a reader \\(r\\), the adversary can always induce a fair execution of \\(B\\) where the fragments \\(I, F_1, F_2, E\\) appear consecutively in that order.\n\n**Lemma 4.4.** If any finite execution of \\(B\\) ends with \\(INV(R)\\), for a READ \\(R\\) then there exists an extension \\(\\alpha\\) which is a fair execution of \\(B\\) and is of the form \\(P(\\alpha) \\circ I(\\alpha) \\circ F_1(\\alpha)^{(v_1)} \\circ F_2(\\alpha)^{(v_2)} \\circ E(\\alpha)^{(v_1, v_2)} \\circ S(\\alpha)\\), where \\(P(\\alpha)\\) is the prefix and \\(S(\\alpha)\\) denotes the rest of the execution.\n\n**Proof.** Consider a finite execution of \\(B\\) that end with \\(INV(R)\\), which occurs at some reader \\(r\\), then the adversary induces the execution fragment \\(I(\\alpha)\\) by delaying all actions, except the internal and output actions at \\(r^{F_1}\\), between the actions \\(INV(R)\\) and the later of the actions \\(send(m_1^1)_{r,s_1}\\) and \\(send(m_2^2)_{r,s_2}\\). Next, the adversary delivers \\(m_1^1\\) at \\(s_1\\) (via the action \\(recv(m_1^1)_{r,s_1}\\)) and delays all actions, other than internal and output actions at \\(s_1^{F_2}\\), until \\(s_1\\) responds with \\(v_1\\), via \\(send(v_1)_{s_1,r}\\); we identify this execution fragment as \\(F_1(\\alpha)^{(v_1)}\\). Subsequently, in a similar manner, the adversary delivers the message \\(m_2^2\\) and delays appropriate actions to induce the execution fragment \\(F_2(\\alpha)^{(v_2)}\\). Finally, the adversary delivers the values \\(v_1\\) and \\(v_2\\) to \\(r\\) (via the events\nFigure 7: The sequence of fair executions of $B$ with three clients with the operation $W$, $R_1$ and $R_2$ eventually leading to the execution $\\alpha_10$ that contradicts the $S$ property. The directed arcs depicts the transposition of execution fragments from the previous execution in the sequence.\n\nThe high-level view of our proof strategy is to create a fair execution $\\alpha$ of $B$ that contradicts the $S$ property. We begin with a fair execution of $B$ that contains reads $R_1$ and $R_2$, and write $W$, where $R_1$ begins after $W$ completes, and $R_2$ begins after $R_1$ completes. Clearly, by the $S$ property both $R_1$ and $R_2$ return $(v_1^1, v_2^1)$. Then we successively create a sequence of fair executions of $B$ (Fig. 7), where we interchange the fragments until we finally reach an execution of where $R_2$ completes before $R_1$ begins, but $R_2$ returns $(v_1^1, v_2^1)$ and $R_1$ returns $(v_0^1, v_0^2)$ which contradicts the $S$ property.\n\nThe following lemma show that in an execution of $B$ with a write $W$ and a read $R_1$, there exists a point in the execution such that if $R_1$ is invoked before that point then $R_1$ returns $(v_0^1, v_0^2)$ and if invoked after that point then $R_1$ returns $(v_1^1, v_2^1)$.\n\n**Lemma 4.5** (Existence of $\\alpha_0$ and $\\alpha_1$). There exist fair executions $\\alpha_0$ and $\\alpha_1$ of $B$ that contain transactions $W$ and $R_1$ with the following properties:\n(i) $\\alpha_0$ can be written as $a_1, \\ldots, a_k \\circ R_1(\\alpha_0)(v_1^0, v_2^0) \\circ S(\\alpha_0)$;\n\n(ii) $\\alpha_1$ can be written as $a_1, \\ldots, a_{k+1} \\circ R_1(\\alpha_1)(v_1^1, v_2^1) \\circ S(\\alpha_1)$; and\n\n(iii) $a_{k+1}$ in $\\alpha_1$ occurs at $r_1^A$,\n\nwhere $k$ is some positive integer and $a_1, \\ldots, a_k$ is a prefix of $a_1, \\ldots, a_{k+1}$.\n\nProof. Now we describe the construction of a sequence $\\{\\gamma_k\\}_{k=0}^\\infty$ of finite executions of $B$ such that each $\\gamma_k$ contains $W$ and $R_1$. Let us consider a fair execution $\\alpha$ of $B$ that contains $W$. Suppose $k$ is any positive integer and suppose $R_1$ is invoked at $r_1^A$ after the execution fragment $a_1, \\ldots, a_{k+1}$, a prefix of $\\alpha$. After the action $INV(R_1)$, the adversary schedules only internal and external actions at $r_1^A$ until both the events $send(m_1^{r_1})_{r_1,s_1}$ and $send(m_2^{r_1})_{r_1,s_2}$ occur, thereby creating an execution fragment of the form $a_1, \\ldots, a_{k+1} \\circ I_1(\\alpha)$. Let us denote $a_1, \\ldots, a_{k+1}$ by $P_{k+1}$.\n\nFollowing this, the adversary delivers the messages $m_1^{r_1}$ at $s_1$, and delays all actions at other automata and also any input action at $s_1$, until $s_1$ sends $v_1$ to $r_1$, therefore, inducing the execution fragment $P_{k+1} \\circ I_1(\\alpha) \\circ F_{1,1}(\\alpha)$ of $B$. Next, the adversary delivers $m_2^{r_1}$ at $s_2$ and delays all actions at other automata and input actions at $s_2$, until $s_2$ sends $v_2$ to $r_1$. Then the adversary delivers $v_1$ and $v_2$ at $r_1$ but it delays actions at other automata and any other input action at $r_1$, until $RESP(R_1)$ occurs. Up to this point this is an execution fragment of $B$, which can be written as $P_{k+1} \\circ I_1(\\alpha) \\circ F_{1,1}(\\alpha)(v_1) \\circ F_{1,2}(\\alpha)(v_2) \\circ E(\\alpha)(v_1^*, v_2^*)$, where $R_1$ responds with $(v_1, v_2)$ such that $(v_1, v_2) \\in \\{(v_1^0, v_2^0), (v_1^1, v_2^1)\\}$. We denote this finite execution prefix as $\\gamma_k$. Therefore, there exists the sequence of such finite executions $\\{\\gamma_k\\}_{k=0}^\\infty$.\n\nIn $\\gamma_0$, $R_1$ precedes $W$ and therefore, by the S property, in $\\gamma_0$, $R_1$ must respond with $(v_1^0, v_2^0)$. On the other hand, if $k$ is large enough such that $a_k$ occurs in $\\alpha$ after the completion of $W$ then by the S property, in $\\gamma_{k+1}$, $R_1$ must return $(v_1^1, v_2^1)$. Therefore, there exists a minimum $k$ where in $\\gamma_k$ $R_1$ returns $(v_1^0, v_2^0)$ and in $\\gamma_{k+1}$, $R_1$ returns $(v_1^1, v_2^1)$. We identify $\\gamma_k$ as $\\alpha_0$ and $\\gamma_{k+1}$ as $\\alpha_1$ as in claims (i) and (ii), respectively.\n\nNow, we show (iii) by eliminating the possibility of $a_{k+1}$ occurring at $s_1^A$, $s_2^A$, $w^A$ or $r_2^A$ by showing contradictions. Our proof is based on the following argument. The S property implies that $R_1$ must respond with values for $o_1$ and $o_2$ corresponding to the same version, which implies that $s_1$ and $s_2$ must send values of the same version. Observe that $R_1$, in $\\alpha_0$ and $\\alpha_1$, returns values for versions 0 (i.e., $(v_1^0, v_2^0)$) and 1 (i.e., $(v_1^1, v_2^1)$), respectively, but the prefixes $P_k$ and $P_{k+1}$ differ from one another only by action $a_{k+1}$. But just one action at any of $s_1$, $s_2$, $r_2$ or $w$ is not enough for $s_1$ and $s_2$ to coordinate to return values of the same version. Therefore, $a_{k+1}$ must occur in $r_1$, which can possibly synchronize by sending some information in $m_1$ and $m_2$ to $s_1$ and $s_2$, respectively.\n\nCase $a_{k+1}$ occurs at $s_1^A$: Consider the prefix of execution $\\alpha_0$ up to the action $a_k$. Suppose the adversary invokes $R_1$ immediately after action $a_k$, i.e., via $INV(R_1)$. By Lemma 4.4 there exists fair execution $\\alpha'$ of $B$ that contains an execution fragment of the form $P_k \\circ I_1(\\alpha') \\circ F_{1,1}(\\alpha')(v_1) \\circ F_{1,2}(\\alpha')(v_2) \\circ E(\\alpha')(v_1^*, v_2^*)$. Note that in both $\\alpha'$ and $\\alpha_1$ we can have $I_1(\\alpha_1) \\supseteq I_1(\\alpha')$ and $F_{1,2}(\\alpha_1) \\subseteq F_{1,2}(\\alpha')$, this is because in both executions the actions of $I_1$ occur entirely at $r_1$ and those of $F_{1,2}$ entirely at $s_2$. As a result, $F_{1,2}(\\alpha')$ must send the same value $v_2^1$ for $o_2$ to $r_2$ as in $F_{1,2}(\\alpha_1)$. Then in $\\alpha'$, by Lemma 4.3, $R_1(\\alpha')$ returns $v_2^1$ for object $o_2$, and by the S property, $R_1(\\alpha')$ returns $(v_1^1, v_2^1)$. But this contradicts the definition of $k$, as the minimum value of $k$ such that $R_1$ responds with $(v_1^1, v_2^1)$.\n\nCase $a_{k+1}$ occurs at $s_2^A$. A contradiction can be shown by following a line of reasoning similar to the preceding case.\nCase $a_{k+1}$ occurs at $w^A$: This can be argued in a similar manner as the previous case and a bit easier because we have $F_{1,1}(\\alpha_1) \\overset{\\alpha_1}{\\leadsto} F_{1,1}(\\alpha')$, and also, $F_{1,2}(\\alpha_1) \\overset{\\alpha_2}{\\leadsto} F_{1,2}(\\alpha')$.\n\nCase $a_{k+1}$ occurs at $r^A_2$: A contradiction can be derived using a line of reasoning as in the previous case.\n\nFrom the above, we conclude that in $\\alpha_1$, action $a_{k+1}$ must occur at $r^A_1$. □\n\nAdditional notation: In the remainder of the section, for the execution fragments $I_i(\\alpha)$, $F_{i,1}(\\alpha)(v_1)$, $F_{i,2}(\\alpha)(v_2)$, $E_i(\\alpha)(v_1,v_2)$ and $S(\\alpha)$, for $i \\in \\{1,2\\}$ we use the notations $I_i$, $F_{i,1}(v_1)$, $F_{i,2}(v_2)$, $E_i(v_1,v_2)$ and $S$, respectively, suppressing the explicit reference to the execution. With regard to any READ $R_i$ if it has an execution fragment of the form $I_i(\\alpha) \\circ F_{i,1}(\\alpha)(v_1) \\circ F_{i,2}(\\alpha)(v_2) \\circ E_i(\\alpha)(v_1,v_2)$ we denote it as $R_i(v_1,v_2)$. Also, wherever the returned values in the fragments are not known, clear from the context or irrelevant we omit them. In the rest of the section, we fix $\\alpha_0$ and $\\alpha_1$, and the value of $k$; we denote the execution fragments $a_1, \\ldots, a_k$ and $a_1, \\ldots, a_{k+1}$ as $P_k$ and $P_{k+1}$, respectively, which are the same irrespective of the execution they appear in.\n\nThe following lemma states the existence of an execution of $B$ where, following a WRITE, there are two consecutive READS and both return the object values updated by the WRITE.\n\n**Lemma 4.6** (Existence of $\\alpha_2$). There exists fair execution $\\alpha_2$ of $B$ that contains transactions $W$, $R_1$ and $R_2$ and can be written in the form $P_{k+1} \\circ R_1(v_1,v_2) \\circ R_2(v_1,v_2) \\circ S$, where both $R_1$ and $R_2$ return $(v_1^2, v_2^2)$.\n\n**Proof.** We can construct a fair execution $\\alpha_2$ of $B$ as follows. Consider the prefix $a_1, \\ldots, a_{k+1} \\circ R_1(\\alpha_1)(v_1,v_2)$ of the execution $\\alpha_1$, from Lemma 4.5. At the end of this prefix, the adversary invokes $R_2$. Now, by Lemma 4.4 due to INV($R_2$) there is an extension of the prefix of the form $a_1, \\ldots, a_{k+1} \\circ R_1(\\alpha_1)(v_1,v_2) \\circ I(\\alpha) \\circ F_1(\\alpha)(v_1) \\circ F_2(\\alpha)(v_2) \\circ E(\\alpha)(v_1,v_2)$. By the $S$ property, we have $v_1 = v_1^2$ and $v_2 = v_2^2$. Therefore, $\\alpha_2$ (Fig. 7) can be written in the form $P_{k+1} \\circ R_1(v_1^2,v_2^2) \\circ R_2(v_1^2,v_2^2) \\circ S$, where $S$ is the rest of the execution. □\n\nBased on the previous execution, the following lemma states that there is a fair execution of $B$ where the $I_2$ occurs earlier than the action $a_{k+1}$ and invocation of $R_1$.\n\n**Lemma 4.7** (Existence of $\\alpha_3$). There exists fair execution $\\alpha_3$ of $B$ that contains transactions $W$, $R_1$ and $R_2$, and can be written in the form $P_k \\circ I_2 \\circ a_{k+1} \\circ R_1(v_1^2,v_2^2) \\circ F_{2,1} \\circ F_{2,2} \\circ E_2 \\circ S$, where both $R_1$ and $R_2$ return $(v_1^2, v_2^2)$.\n\n**Proof.** Consider the execution $\\alpha_2$ as in Lemma 4.6. In the execution fragment $I_1 \\circ F_{1,1}(v_1) \\circ F_{1,2}(v_2) \\circ E_1(v_1,v_2)$ in $\\alpha_2$, none of the actions occur at $r_2$ and by Lemma 4.5, $a_{k+1}$ occurs at $r_1^A$, also the actions in $I_2$ occur only at $r_2$. Starting with $\\alpha_2$, and by repeatedly using Lemma 4.2 we create a sequence of four fair executions of $B$ by repeatedly swapping $I_2$ with the execution fragments $E_1(v_1^2,v_2^2)$, $F_{1,2}$, $F_{1,1}$ and $I_1$, which appears in $I_1 \\circ F_{1,1}(v_1) \\circ F_{1,2}(v_2) \\circ E_1(v_1,v_2) \\circ I_2$, where the following sequence of execution fragments $I_1 \\circ F_{1,1}(v_1) \\circ F_{1,2}(v_2) \\circ I_2 \\circ E_1(v_1,v_2)$ (by commuting $I_2$ and $E_1(v_1,v_2)$); $I_1 \\circ E_1(v_1,v_2) \\circ I_2 \\circ F_{1,2}(v_2) \\circ F_{1,1}(v_1)$ (by commuting $I_2$ and $F_{1,1}(v_1)$) appear. Finally, we have an execution $\\alpha'$ of the form $P_{k+1} \\circ I_2 \\circ R_1(v_1^2,v_2^2) \\circ F_{2,1}(v_1) \\circ F_{2,2}(v_2) \\circ E_2(v_1^2,v_2^2) \\circ S$ (by commuting $I_2$ and $I_1$). Next, from $\\alpha'$, by using Lemma 4.2 and swapping $a_{k+1}$ with $I_2$ we show the existence of a fair execution $\\alpha_3$ as stated in the lemma. □\nIn the following lemma, we show that we can create a fair execution $\\alpha_4$, of $B$, where $F_{2,2}$ occurs immediately before $E_{1}(v_{1}^{1},v_{2}^{1})$, while $R_1$ and $R_2$ both return $(v_{1}^{1},v_{2}^{1})$.\n\n**Lemma 4.8** (Existence of $\\alpha_4$). There exists fair execution $\\alpha_4$ of $B$ that contains transactions $W$, $R_1$ and $R_2$ and can be written in the form $P_k \\circ I_2 \\circ a_{k+1} \\circ I_1 \\circ F_{1,1} \\circ F_{1,2} \\circ F_{2,2} \\circ E_{1} \\circ F_{2,1} \\circ E_2 \\circ S$, where both $R_1$ and $R_2$ return $(v_{1}^{1},v_{2}^{1})$.\n\n**Proof.** We start with an execution $\\alpha_3$, as in Lemma 4.7 and apply Lemma 4.2 twice.\n\nFirst, by Lemma 4.2, we know there exists a fair execution $\\alpha'$ of $B$ where $F_{2,1}$ (identify as $G_1$) and $F_{2,2}$ (identify as $G_2$) are interchanged since actions of $F_{2,1}$ occurs solely at $s_1$ and those of $F_{2,2}$ at $s_2$, and $F_{2,1}$ and $F_{2,2}$ return $v_{1}^{1}$ and $v_{2}^{1}$, respectively, to $r_2$.\n\nNext, by Lemma 4.2, there is a fair execution of $B$, say $\\alpha_4$ where the fragments $E_1$ (identify as $G_1$) and $F_{2,2}$ (identify as $G_2$) are interchanged, with respect to $\\alpha'$, because the actions in $E_1$ occur at $r_1$ and those of $F_{2,2}$ at $s_2$. Furthermore, $\\alpha_4$ can be written in the form $P_k \\circ I_2 \\circ a_{k+1} \\circ I_1 \\circ F_{1,1} \\circ F_{1,2} \\circ F_{2,2} \\circ E_{1} \\circ F_{2,1} \\circ E_2 \\circ S$.\n\nNext, we create a new fair execution $\\alpha_5$ of $B$ where $F_{2,2}$ occurs before $F_{1,2}$. However, because the actions in both of these execution fragments occur at the same automaton care has to be taken to swap these fragments compared to $\\alpha_4$.\n\n**Lemma 4.9** (Existence of $\\alpha_5$). There exists fair execution $\\alpha_4$ of $B$ that contains transactions $W$, $R_1$ and $R_2$ and can be written in the form $P_k \\circ I_2 \\circ a_{k+1} \\circ I_1 \\circ F_{1,1} \\circ F_{1,2} \\circ F_{2,2} \\circ E_{1} \\circ F_{2,1} \\circ E_2 \\circ S$, where both $R_1$ and $R_2$ return $(v_{1}^{1},v_{2}^{1})$.\n\n**Proof.** In $\\alpha_4$, all actions in $F_{1,2}$ and $F_{2,2}$ occur at $s_2$. Consider the prefix of $\\alpha_4$ that ends with $F_{1,1}$. We extend this prefix as follows. In this prefix, the actions $send(m_{2}^{r_2})_{r_2,s_2}$ and $send(m_{1}^{r_1})_{r_1,s_2}$ do not have their corresponding $recv$ actions. Suppose the adversary delivers $m_{2}^{r_2}$ at $s_2$ (via the action $recv(m_{2}^{r_2})_{r_2,s_2}$) and delays all actions, other than internal and output actions at $s_2$, until $s_2$ responds with $v_2$, via action $send(v_2)_{s_2,r_2}$. This extended execution fragment is of the form $F_{2,2}$.\n\nSimilarly, the adversary further extends the execution by placing the action $recv(m_{2}^{r_1})_{r_1,s_2}$ at $s_2$ and create the execution fragment of form $F_{1,2}$. Note that, so far, the actions due to the above extensions are entirely at $s_2$. Suppose the adversary makes the execution fragments $E_1$ next, by delaying values sent during $F_{1,1}$ and $F_{1,2}$ via the actions $recv(v_1)_{s_1,r_1}$ and $recv(v_2)_{s_2,r_1}$, respectively, at $r_1$. Then $F_{2,1}$ appear next, such that this fragment contains exactly the same sequence of actions as in the corresponding execution fragment in $\\alpha_4$. This is possible because they are not influenced by any output action in $F_{2,2}$ or $F_{1,2}$. Suppose the adversary places the execution fragment $E_2$ next. Let us denote the fair execution that is an extension of this finite execution so far as $\\alpha_5$, which is of the form $P_k \\circ I_2 \\circ a_{k+1} \\circ I_1 \\circ F_{1,1} \\circ F_{1,2} \\circ E_{1} \\circ F_{2,1} \\circ E_2 \\circ S$. Now we need to argue about the values returned by the reads.\n\nNote that the execution fragment $F_{1,1}(\\alpha_4)$ in both $\\alpha_4$ and $\\alpha_5$ is the same, therefore, $F_{1,1}(\\alpha_4) \\approx F_{1,1}(\\alpha_5)$. Hence as in $\\alpha_4$, $s_1$ returns $v_1^{1}$ in the execution fragment $F_{1,1}$ in $\\alpha_5$. Next by Lemma 4.3 for $R_1$, $s_2$ returns $v_2^{1}$ in $F_{1,2}$ and hence by the $S$ property, $R_1(\\alpha_5)$ returns $(v_1^{1},v_2^{1})$, i.e., that $r_1$ returns the new version of object values. Therefore, $F_{1,1}(\\alpha_4)$, $F_{1,2}$ and $E_1$ are of the form $F_{1,1}^{(v_1^{1})}$, $F_{1,2}^{(v_2^{1})}$ and $E_1^{(v_1^{1},v_2^{1})}$, respectively.\n\nNote that by construction of $\\alpha_5$ above, the execution fragment $F_{2,1}$ in both $\\alpha_4$ and $\\alpha_5$ is the same, therefore, $F_{2,1}(\\alpha_4) \\approx F_{2,1}(\\alpha_5)$. Hence as in $\\alpha_4$, $s_1$ returns $v_1^{1}$ in the execution fragment\nwe will be working on moving the execution fragments of $R$ where we conclude that for any extension of $S$ property, $R_2$ returns $(v^1_1, v^2_1)$ and hence $E_2$ is of the form $E_2^{(v^1_1, v^2_1)}$.\n\nFrom the above argument we know that $\\alpha_5$ is of the form $P_k \\circ I_2 \\circ a_{k+1} \\circ I_1 \\circ F_{1,1} \\circ F_{1,2} \\circ F_{2,2} \\circ F_{2,1} \\circ S$, where $F_{2,1}(\\alpha_5)$ in $\\alpha_5$, i.e., of the form $F_{2,1}(\\alpha_5)^{(v^1)}$. Since $s_1$ returns $v^1_1$ in $F_{2,1}$ in $\\alpha_5$, by Lemma \\ref{lem:fairness} and the $S$ property, $R_2$ returns $(v^1_1, v^2_1)$ and hence $E_2$ is of the form $E_2^{(v^1_1, v^2_1)}$.\n\nIn the next lemma, we show the existence of a fair execution of $B$ where $R_1$ returns $(v^0_1, v^0_2)$ and $I_2$ occurs immediately after $a_k$ and $R_2$ responds with $(v^1_1, v^2_1)$. In fact, this is the most important of the sequence of fair executions of $B$ (Fig. \\ref{fig:fairness}) because later with this we prove in Theorem \\ref{thm:fairness} the existence of a fair execution of $B$ where a READ returns object-values of an earlier version compared to a previous READ that is not concurrent with it.\n\n**Lemma 4.10 (Existence of $\\alpha_6$).** There exists fair execution $\\alpha_6$ of $B$ that contains transactions $W$, $R_1$ and $R_2$ and can be written in the form $P_k \\circ I_2 \\circ I_1 \\circ F_{1,1} \\circ F_{1,2} \\circ F_{2,2} \\circ F_{2,1} \\circ E_1 \\circ F_{2,1} \\circ E_2 \\circ S$, where $R_1$ returns $(v^0_1, v^0_2)$ and $R_2$ returns $(v^1_1, v^2_1)$.\n\n**Proof.** The crucial part of this proof is to carefully use the result of Lemma \\ref{lem:fairness} so that $R_1$ returns $(v^0_1, v^0_2)$, instead of $(v^1_1, v^2_1)$. Note that by the construction of $\\alpha_5$, as in Lemma \\ref{lem:prefix} the same prefix $P_k$ appears in the fair executions $\\alpha_5$, and the executions $\\alpha_0$ and $\\alpha_1$ as in Lemma \\ref{lem:fairness} where $k$ is defined as in Lemma \\ref{lem:prefix}.\n\nNote that by Lemma \\ref{lem:fairness}, action $a_{k+1}$ occurs at $r^A_1$. In $\\alpha_5$, in the execution fragment $a_{k+1} \\circ I_1 \\circ F_{1,1} \\circ F_{1,2}$, the actions in execution fragment $a_{k+1} \\circ I_1$ occur at $r^A_1$; actions in $F_{1,1}$ occur at $s^A_1$, and actions in $F_{1,2}$ occur at $s^A_2$. Now consider the prefix of execution $\\alpha_4$ ending with $I_2$ and suppose the adversary invokes $R_1$ immediately after $I_2$ (instead of after $a_{k+1}$) and extends by the execution fragment $I_1 \\circ F_{1,1} \\circ F_{2,2}$ to create a new finite execution $\\epsilon$, which is of the form $P_k \\circ I_2 \\circ I_1 \\circ F_{1,1} \\circ F_{2,2}$. Note that as a result, $a_{k+1}$ may not be in $\\epsilon$ because we are introducing changes before $a_{k+1}$ can occur.\n\nNote that if in the prefix $P_k \\circ I_2(\\epsilon) \\circ I_1(\\epsilon) \\circ F_{1,1}(\\epsilon) \\circ F_{2,2}(\\epsilon)$ of $\\epsilon$ we ignore the actions in $I_2(\\epsilon)$ then the remaining execution is the same as the prefix $P_k \\circ I_1(\\alpha_0) \\circ F_{1,1}(\\epsilon) \\circ F_{2,2}(\\epsilon)$ of $\\alpha_0$ in Lemma \\ref{lem:fairness}. Here we explicitly use the notations $\\epsilon$ and $\\alpha_0$ to avoid confusion. Since the actions in $I_2(\\epsilon)$ have no influence in the actions on $I_1(\\epsilon) \\circ F_{1,1}(\\epsilon) \\circ F_{2,2}(\\epsilon)$, therefore, we have $F_{1,1}(\\epsilon) \\cong F_{1,1}(\\alpha_0)$, and hence by Lemma \\ref{lem:prefix} $F_{1,1}(\\epsilon)$ returns $v^0_1$ as in $F_{1,1}(\\alpha)$, i.e., in $F_{1,1}$, $s_1$ returns $v^0_1$. Now by Lemma \\ref{lem:fairness} we conclude that for any extension of $\\epsilon$, say $\\gamma$, READ $R_1(\\gamma)$ returns $v^0_1$ for object $o_1$ and by the $S$ property $R_1(\\gamma)$ returns $(v^1_1, v^2_1)$ also, since $F_{2,2}(\\alpha_5) \\cong F_{2,2}(\\epsilon) \\cong F_{2,2}(\\gamma)$ by Lemma \\ref{lem:prefix} and the $S$ property, $R_2(\\gamma)$ must return $(v^1_1, v^2_1)$. Therefore, $\\gamma$ has an extension to a fair execution $\\alpha_6$ (Fig. \\ref{fig:fairness}) which is of the form $P_k \\circ I_2 \\circ I_1 \\circ F_{1,1} \\circ F_{1,2} \\circ F_{2,2} \\circ F_{2,1} \\circ E_1 \\circ F_{2,1} \\circ E_2 \\circ S$ as in the statement of the lemma.\n\nIn the following lemma, starting from $\\alpha_6$ in Lemma \\ref{lem:fairness} we create a fair execution $\\alpha_7$ for $B$ where $F_{2,1}$ appears before $F_{1,2} \\circ E_1$, where $R_1$ returns $(v^0_1, v^0_2)$ and $R_2$ returns $(v^1_1, v^2_1)$. At high level, we will be working on moving the execution fragments of $R_2$ forward, a little at a time, until finally we have $R_2$ finishing before $R_1$ starts. This simply uses commutativity since the actions in the swapped execution fragments occurs at different automata.\n\n**Lemma 4.11 (Existence of $\\alpha_7$).** There exists fair execution $\\alpha_7$ of $B$ that contains transactions $W$, $R_1$ and $R_2$, and can be written in the form $P_k \\circ I_2 \\circ I_1 \\circ F_{1,1} \\circ F_{2,2} \\circ F_{2,1} \\circ E_1 \\circ E_2 \\circ S$ where $R_1$ returns $(v^0_1, v^0_2)$ and $R_2$ returns $(v^1_1, v^2_1)$.\n\n25\nProof. This result is proved by applying the result of Lemma 4.2 to the fair execution created in Lemma 4.10. Suppose, $\\alpha_6$ (Fig. 7) is a fair execution as in Lemma 4.10 where in the execution fragment $F_1(v_1^0, v_2^0) \\circ F_{2,1}$ we identify $E_1(v_1^0, v_2^0)$ as $G_1$ and $F_{1,2}(v_1^0)$ as $G_2$. The actions of $G_1$ and $G_2$ occur at two distinct automata, therefore, we can use the result of Lemma 4.2 to argue that there exists a fair execution $\\alpha'$ of $B$ that contains the execution fragment $F_{2,1} \\circ E_1(v_1^0, v_2^0)$, and $\\alpha_6$ and $\\alpha'$ are identical in the prefixes and suffixes corresponding to $G_1$ and $G_2$.\n\nNow, $\\alpha'$ contains $F_{1,2} \\circ F_{2,1}$, where the actions in $F_{1,2}$ (identify as $G_1$) and $F_{2,1}$ (identify as $G_2$) occur at distinct automata. Hence, by Lemma 4.2 there exists an execution $\\alpha_7$ of the form $P_k \\circ I_2 \\circ I_1 \\circ F_{1,2} \\circ F_{2,1} \\circ F_1(v_2^0) \\circ F_{2,2} \\circ F_{1,2} \\circ E_1(v_1^0, v_2^0) \\circ E_2(v_2^0) \\circ S$.\n\nIn the following lemma by using simple commuting arguments of Lemma 4.2 we show the existence of a fair execution $\\alpha_7$ of $B$ where $F_{2,2}$ appears before $I_1 \\circ F_{1,1}$, where $R_1$ returns $(v_1^0, v_2^0)$ and $R_2$ returns $(v_1^0, v_2^0)$.\n\n**Lemma 4.12** (Existence of $\\alpha_8$). There exists fair execution $\\alpha_8$ of $B$ that contains transactions $W$, $R_1$ and $R_2$ and can be written in the form $P_k \\circ I_2 \\circ F_{2,2} \\circ I_1 \\circ F_{1,1} \\circ F_{2,1} \\circ F_{2,2} \\circ E_1 \\circ E_2 \\circ S$, where $R_1$ returns $(v_1^0, v_2^0)$ and $R_2$ returns $(v_1^0, v_2^0)$.\n\n**Proof.** Consider the fair execution $\\alpha_7$ of $B$ as in Lemma 4.11. In the context of $\\alpha_7$ (Fig. 7), the actions in $F_{1,1}$ (identify as $G_1$) occur at $s_1^A$ and those in $F_{2,2}$ (identify as $G_2$) at $s_2^A$. Then by Lemma 4.2 there exists a fair execution $\\alpha'$ of $B$, of the form $P_k \\circ I_2 \\circ I_1 \\circ F_{2,2} \\circ F_{1,1} \\circ F_{2,1} \\circ F_{1,2} \\circ E_1 \\circ E_2 \\circ S$, where $F_{2,2}$ and $F_{1,1}$ are interchanged.\n\nSince actions in $F_{2,2}$ (identify as $G_1$) occur at $s_1^A$ and those in $I_1$ (identify as $G_1$) occur at $s_1^A$, then by Lemma 4.2 there is a fair execution of $B$, $\\alpha_8$ where $F_{2,2}$ appear before $I_1$, i.e., of the form $P_k \\circ I_2 \\circ F_{2,2} \\circ I_1 \\circ F_{1,1} \\circ F_{2,1} \\circ E_1 \\circ E_2 \\circ S$, where $F_{2,2}$ and $I_1$ are interchanged.\n\nBy (ii) of Lemma 4.2 we have $F_{2,1}(\\alpha') \\sim F_{2,1}(\\alpha_8)$ hence $F_{2,1}$ sends $v_1^0$ and $F_{1,1}$ and $F_{1,2}$ sends $v_1^0$ and $v_2^0$, respectively. So considering these returned values we have $\\alpha_8$ (Fig. 7) in the form as stated in the lemma.\n\nThe following lemma shows the existence of a fair execution of $B$, $\\alpha_9$, where we move $F_{2,1}$ forward past $F_{1,1}$.\n\n**Lemma 4.13** (Existence of $\\alpha_9$). There exists fair execution $\\alpha_9$ of $B$ that contains transactions $W$, $R_1$ and $R_2$ and can be written in the form $P_k \\circ I_1 \\circ F_{2,1} \\circ I_1 \\circ F_{1,1} \\circ F_{2,1} \\circ F_{2,2} \\circ F_1(v_2^0) \\circ F_{1,2} \\circ E_1(v_1^0, v_2^0) \\circ E_2(v_2^0) \\circ S$ where $R_1$ returns $(v_1^0, v_2^0)$ and $R_2$ returns $(v_1^0, v_2^0)$.\n\n**Proof.** In $\\alpha_8$ from Lemma 4.12 all the actions in $I_1$ occur at $r_1$; those in $F_{1,1}$ occur at $s_1$; and the actions in $F_{2,1}$ occur only at $s_1$. Note that actions of both execution fragments $F_{2,1}$ and $F_{1,1}$ occur at $r_1$. Consider the prefix of $\\alpha_8$ that ends with $I_1$ then suppose the adversary extends this prefix by adding an execution fragment of the form $F_{2,1} \\circ F_1(v_1^0, v_2^0)$ as follows. First note that the action $send(m_1^0)_{r_2, s_1}$ and $send(m_1^0)_{r_1, s_1}$ appears in the prefix but do not have corresponding $recv$ actions. The adversary places action $recv(m_1^0)_{r_2, s_1}$, and allows an execution fragment of the form $F_{2,1}$ to appear. Now, immediately after this the adversary further extends it with an execution fragment of the form $F_{1,1}$ by placing action $recv(m_1^0)_{r_1, s_1}$.\n\nThe last step can be argued by the fact that none of the actions in $F_{1,2}$ can be affected by any of the output actions at $F_{2,1}$ and $F_{1,1}$. Note that the actions in $F_{1,2}$ are taking place at $s_2$, which is not affected by the above fragments, and therefore, at the end of this fragment $s_2$ returns.\n$v_1^0$, as in $\\alpha_8$. But by $S$ property $F_{1,1}$ has to return $v_1^0$ as well. Note that a careful argument can be done by using Theorem 2.3 to conclude the same. Following this the adversary allows the rest of the execution by adding an execution fragment of the form $E_1 \\circ E_2 \\circ S$. The resulting fair execution is of the form $P_k \\circ I_2 \\circ F_{2,2}^{(v_2^1,v_2^0)} \\circ I_1 \\circ F_{2,1} \\circ F_{1,10} \\circ F_{1,2}^{(v_1^0,v_1^0)} \\circ E_1 \\circ E_2 \\circ S$, where we retained the values wherever it is known, and we denote this fair execution by $\\alpha_9$.\n\nNow, we argue about the return values in $\\alpha_9$. Applying Lemma 4.2 to $R_2$ and $F_{2,2}$ implies that $R_2$ returns $(v_1^1,v_2^1)$. Similarly, applying Lemma 4.2 to $R_1$ and $F_{1,2}$ implies that $R_1$ must return $(v_1^0,v_2^0)$ in $\\alpha_9$. □\n\nNow we show the existence of a fair execution of $B$ where the execution fragments corresponding to $R_1$ appears before $R_2$, where $R_1$ returns $(v_1^0,v_2^0)$ and $R_2$ completes by returning $(v_1^1,v_2^1)$.\n\n**Lemma 4.14** (Existence of $\\alpha_{10}$). There exists fair execution $\\alpha_{10}$ of $B$ that contains transactions $W$, $R_1$ and $R_2$ and can be written in the form $P_k \\circ R_2^{(v_2^1,v_2^0)} \\circ R_1^{(v_1^0,v_1^0)} \\circ E_2 \\circ E_2^{(v_2^1,v_2^0)} \\circ S$, where $R_1$ returns $(v_1^0,v_2^0)$ and $R_2$ returns $(v_1^1,v_2^1)$.\n\n**Proof.** Now, by using Lemma 4.2 to $\\alpha_9$, we can interchange $F_{2,1}$ and $I_1$ to create a fair execution $\\alpha_{10}$ (Fig. 7) of $B$, which is of the form $P_k \\circ I_2 \\circ F_{2,2}^{(v_2^1,v_2^0)} \\circ P_{2,1}^{(v_1^1)} \\circ R_2^{(v_2^1,v_2^0)} \\circ E_1 \\circ E_1^{(v_2^1,v_2^0)} \\circ E_2 \\circ E_2^{(v_2^1,v_2^0)} \\circ S$, where the returned values are determined by Lemma 4.1.\n\nNote that in the execution fragment none of the actions in the execution fragment $I_1 \\circ F_{1,1}^{(v_1^0)} \\circ F_{1,2}^{(v_1^0)} \\circ F_{1,2}^{(v_1^0,v_1^0)} \\circ F_{2,2}^{(v_1^1,v_2^0)} \\circ E_1^{(v_2^1,v_2^0)} \\circ E_2^{(v_2^1,v_2^0)}$ occur at $r_2^A$ and in $E_2^{(v_2^1,v_2^0)}$ each of the action occur at $r_1^A$. Therefore, by applying Lemma 4.2 we can consecutively swap $E_2$ with $E_1$, $F_{1,2}$, $I_1$ and $F_{1,1}$ we create a sequence of four fair executions of $B$ to arrive at fair execution $\\alpha_{10}$ (Fig. 7) of the form $P_k \\circ R_2^{(v_2^1,v_2^0)} \\circ R_1^{(v_1^0,v_1^0)} \\circ E_2^{(v_2^1,v_2^0)} \\circ S$. □\n\nThe following statement proves the statement of the SNOW Theorem by showing the existence of fair execution $\\alpha_{10}$, of $B$, where $R_2$ completes before $R_1$ is invoked and $R_2$ completes by returning $(v_1^1,v_2^1)$ whereas $R_1$ returns $(v_1^0,v_2^0)$, which violates the $S$ property in $\\alpha_{10}$.\n\n**Theorem 4.15.** The SNOW properties cannot be implemented in a system with two readers and one writer, for two servers even in the presence of client-to-client communication.\n\n**Proof.** Note that in $\\alpha_{10}$, $R_2$ completes by returning $(v_1^1,v_2^1)$ and $R_1$, although invoked after $R_2$ returns $(v_1^0,v_2^0)$, is initiated and as a result $\\alpha_{10}$ violates the $S$ property. □\n\n## 5 Condition for proving strict serializability\n\nIn this section, we derive a useful property for executions of algorithms that implement objects of data type $O_T$ that will later help us show the strict serializability property ($S$ property) of algorithms presented in later sections.\n\nAlthough the strict serializability property in transaction-processing systems is a well-studied topic, the specific setting considered in this paper is much simpler. Therefore, this allows us to derive simpler conditions to prove the safety of these algorithms. A wide range of transaction types and transaction processing systems are considered in the literature. For example, in [13], Papadimitriou defined the strict serializability conditions as a part of developing a theory for analyzing transaction processing systems. In this work, each transaction $T$ consists of a set of write operations $W_i$ at individual objects, and a set of read operations $R$ from individual objects, where the operations\nin $W$ must complete before the operations in $R$ execute. Other types of transaction processing systems allow nested transactions $\\Pi$, where the transactions may contain sub-transactions $\\mathcal{2}$ which may further contain a mix of read or write operations, or even child-transactions. In most transaction processing systems considered in the literature, transactions can be aborted so as to handle failed transactions. As a result, the serializability theories are developed while considering the presence of aborts. However, in our system, we do not consider any abort, nor any client or server failures. A transaction in our system is either a set of independent writes or a set of reads (see Section 2.2) with all the reads or writes in a transaction operating on different objects. Such simplifications allow us to formulate an equivalent condition for the execution of an algorithm to prove the S property of such algorithms while implementing an object of data type $O_T$.\n\nWe note that an execution of a variable of type $O_T$ is a finite sequence $v_0, \\text{INV}_1, \\text{RESP}_1, v_1, \\text{INV}_2, \\text{RESP}_2, v_2, \\ldots, v_r$ or an infinite sequence $v_0, \\text{INV}_1, \\text{RESP}_1, v_1, \\text{INV}_2, \\text{RESP}_2, v_2, \\ldots$, where $\\text{INV}$’s and $\\text{RESP}$’s are invocations and responses, respectively. The $v_i$’s are tuples of the form $(v_1, v_2, \\ldots, v_k) \\in \\Pi_{i=1}^q V_i$, that corresponds to the latest values stored across the objects $a_1, a_2, \\ldots, a_k$, and the values in $v_0$ are the initial values of the objects. Any adjacent quadruple such as $v_i, \\text{INV}_{i+1}, \\text{RESP}_{i+1}, v_{i+1}$ is consistent with the $f$ function for an object of type $O_T$ (see Section 5). Now, the safety property of such an object is a trace that describes the correct response to a sequence of INV’s when all the transactions are executed sequentially. The strict serializability of $O_T$ says that each trace produced by an execution of $O_T$ with concurrent transactions appears as some trace of $O_T$. We describe this below in more detail.\n\n**Definition 2** (Strict-serializability). Let us consider an execution $\\beta$ of an object of type $O_T$, such that the invocations of any transaction at any client respects the well-formedness property. Let $\\Pi$ denote the set of complete transactions in $\\beta$ then we say $\\beta$ satisfies the strict-serializability property for $O_T$ if the following are possible:\n\n(i) For every complete read or write transaction $\\pi$ we insert a point (serialization point) $\\pi_s$ between the actions $\\text{INV}(\\pi)$ and $\\text{RESP}(\\pi)$.\n\n(ii) We select a set $\\Phi$ of incomplete transactions in $\\beta$ such that for each $\\pi \\in \\Phi$ we select a response $\\text{RESP}(\\pi)$.\n\n(iii) For each $\\pi \\in \\Phi$ we insert $\\pi_s$ somewhere after $\\text{INV}(\\pi)$ in $\\beta$, and remove the $\\text{INV}$ for the rest of the incomplete transactions in $\\beta$.\n\n(iv) If we assume for each $\\pi \\in \\Pi \\cup \\Phi$ both $\\text{INV}(\\pi)$ and $\\text{RESP}(\\pi)$ to occur consecutively at $\\pi_s$, with the interval of the transaction shrunk to $\\pi_s$, then the sequence of transactions in this new trace is a trace of an object of data type $O_T$.\n\nNow, we consider any automaton $B$ that implements an object of type $O_T$, and prove a result that serves us an equivalent condition for proving the strict serializability property of $B$. Any trace property $P$ of an automaton is a safety property if the set of executions in $P$ is non-empty; prefix-closed, meaning any prefix of an execution in $P$ is also in $P$; and limit-closed, i.e., if $\\beta_1, \\beta_2, \\ldots$ is any infinite sequence of executions in $P$ is such that $\\beta_i$ is prefix of $\\beta_{i+1}$ for any $i$, then the limit $\\beta$ of the sequence of executions $\\{\\beta_i\\}_{i=0}^{\\infty}$ is also in $P$. From Theorem 13.1 in [10], we know that the trace property, which we denote by $P_{\\text{SC}}$, of any well-formed execution of $B$ that satisfies the strict-serializability property is a safety property. Moreover, from Lemma 13.10 in [10] we can deduce that if every execution of $B$ that is well-formed and failure-free, and also contains\nno incomplete transactions, satisfies $P_{SC}$, then any well-formed execution of $B$ that can possibly have incomplete transactions is also in $P_{SC}$. Therefore, in the following lemma, which gives us an equivalent condition for the strict serializability property of an execution $\\beta$, we consider only executions without any incomplete transactions. The lemma is proved in a manner similar to Lemma 13.16 in [10], for atomicity guarantee of a single multi-reader multi-writer object.\n\n**Lemma 5.1.** Let $\\beta$ be an execution (finite or infinite) of an automaton $B$ that implements an object of type $O_T$, which consists of a set of $k$ sub-objects. Suppose all clients in $\\beta$ behave in a well-formed manner. Suppose $\\beta$ contains no incomplete transactions and let $\\Pi$ be the set of transactions in $\\beta$. Suppose there exists an irreflexive partial ordering ($\\prec$) among the transactions in $\\Pi$, such that,\n\nP1 For any transaction $\\pi \\in \\Pi$ there are only a finite number of transactions $\\phi \\in \\Pi$ such that $\\phi \\prec \\pi$;\n\nP2 If the response event for $\\pi$ precedes the invocation event for $\\phi$ in $\\beta$, then it cannot be that $\\phi \\prec \\pi$;\n\nP3 If $\\pi$ is a write transaction in $\\pi$ and $\\phi$ is any transaction in $\\Pi$, then either $\\pi \\prec \\phi$ or $\\phi \\prec \\pi$; and\n\nP4 A tuple $v \\equiv(v_{i_1}, v_{i_2}, \\ldots, v_{i_q})$ returned by a READ($o_{i_1}, o_{i_2}, \\ldots, o_{i_q}$), where $q$ is any positive integer, $1 \\leq q \\leq k$, is such that $v_{i_j}$, $j \\in \\{1, \\cdots, q\\}$ is written in $\\beta$ by the last preceding (w.r.t. $\\prec$) write transaction that contains a write($o_{i_j}, *$), or the initial value $v_{i_j}^0$ if no such write exists in $\\beta$.\n\nThen execution $\\beta$ is strictly serializable.\n\n**Proof.** We discuss how to insert a serialization point $*_{\\pi}$ in $\\beta$ for every transaction $\\pi \\in \\Pi$. First, we add $*_{\\pi}$ immediately after the latest of the invocations of $\\pi$ or $\\phi \\in \\Pi$ such that $\\phi \\prec \\pi$. Note that according to condition P1 for $\\pi$ there are only finite number of such invocations in $\\beta$, therefore, $*_{\\pi}$ is well-defined. Now, since the order of the invocation events of the transactions in $\\Pi$ are already defined the order of the corresponding set of serialization points are well-defined except for the case when more than one serialization points are placed immediately after an invocation. In the case such multiple serialization points corresponding to an invocation we order these serialization points in accordance with the $\\prec$ relation of the underlying transactions.\n\nNext, we show that for any pair of transactions $\\phi, \\pi \\in \\Pi$ if $\\phi \\prec \\pi$ then $*_{\\phi}$ precedes $*_{\\pi}$. Suppose $\\phi \\prec \\pi$. By construction, each of $\\pi_s$ and $\\phi_s$ appear immediately after some invocation of some transaction in $\\Pi$. If both $\\pi_s$ and $\\phi_s$ appear immediately after the same invocation, then since $\\phi \\prec \\pi$, by construction of $\\pi_s$, $\\pi_s$ is ordered after $\\phi_s$. Also, if the invocations after which $\\pi_s$ and $\\phi_s$ appear are distinct, then by construction of $\\pi_s$, $\\pi_s$ appear after $\\phi_s$ since $\\phi \\prec \\pi$.\n\nNext we argue that each $*_{\\pi}$ serialization point for any $\\pi \\in \\Pi$ is placed between the invocation $INV(\\pi)$ and responses $RESP(\\pi)$. By construction, $*_{\\pi}$ is after $INV(\\pi)$. To show that $*_{\\pi}$ is before $RESP(\\pi)$ for the sake of contradiction assume that $*_{\\pi}$ appears after $RESP(\\pi)$. By construction, $*_{\\pi}$ must be after $INV(\\phi)$ for some $\\phi \\in \\Pi$ and $\\phi \\neq \\pi$, they by the condition of construction of $\\pi_s$ we have $\\phi \\prec \\pi$. But from above $INV(\\phi)$ occurs after $RESP(\\pi)$, i.e., $\\pi$ completes before $\\phi$ in invoked which means, by property $P2$, we cannot have $\\phi \\prec \\pi$, a contradiction.\n\nNext, we show that if we were to shrink the transactions intervals to their corresponding serialization points, the resulting trace would be a trace of the underlying data type $O_T$. In other\nwords, we show any \\texttt{READ}(o_i, o_2, \\cdots, o_k) returns the values \\(v_{i_1}, v_{i_2}, \\cdots, v_{i_p}\\), such that each value \\(v_{i_j}, j \\in [q]\\), was written by the immediately preceding (w.r.t. the serialization points) \\texttt{WRITE} that contained \\texttt{WRITE}(o_i, v_{i_j}) or the initial values if no such previous \\texttt{WRITE} exists. Let us denote the set of \\texttt{WRITTEN} that precedes (w.r.t. \\(<\\)) by \\(\\Pi^\\prec_W\\), i.e., \\(\\phi \\in \\Pi^\\prec_W \\phi\\) is a write and \\(\\phi \\prec \\pi\\). By property \\(P3\\), all transactions in \\(\\Pi^\\prec_W\\) are totally-ordered. By property \\(P4\\), \\(v_{i_j}\\) must be the value updated by the most recent \\texttt{WRITE} in \\(\\Pi^\\prec_W\\). Since the total order of serialization points are consistent with \\(<\\) and hence the \\(v_{i_j}\\) corresponds to the write operation of a \\texttt{WRITE} transaction with the most recent serialization point and contains a operation of type \\texttt{WRITE}(o_i, *).\n\n\\[\\square\\]\n\n6 \\textbf{SNOW on MWSR with client-to-client messages}\n\nIn this section, we present algorithm \\(A\\) for transaction processing in the multiple-writers single-reader (MWSR) setting, and prove that any fair and well-formed execution of \\(A\\) satisfies the SNOW properties. In practice, a system with a single reader may not be very useful but this algorithm serves as counter example algorithm to exhibit the point that if client-to-client communication is allowed it is still possible to implement the SNOW properties. Algorithm \\(A\\) shows that if client-to-client messaging is allowed, it is possible to have algorithms for transaction processing with two clients that satisfies the SNOW properties. We consider a system where there are \\(\\ell \\geq 1\\) writers with ids \\(w_1, w_2, \\cdots, w_\\ell\\) (we denoted this set by \\(W\\)), one reader with id \\(r\\), and \\(k \\geq 1\\) servers with ids \\(s_1, s_2, \\cdots, s_k\\) (denote as \\(S\\)) that maintains the objects \\(o_1, \\cdots, o_k\\), respectively. We assume writers can send messages to the reader, and the reader can respond back to the writers, i.e., we allow client-to-client messages. Note that for a two-client system, when both clients are of the same type, i.e., two writers or two reads, the SNOW properties are trivially satisfied.\n\nThe steps of algorithm \\(A\\) are presented in Fig.4. We assume that each of the processes are run in a single-threaded manner, and therefore, each of the servers or the clients executes the algorithmic steps sequentially. For uniquely identifying a \\texttt{WRITE} transaction we use keys in algorithm \\(A\\). A key \\(\\kappa\\) is defined as a pair \\((z, w)\\), where \\(z \\in \\mathbb{N}\\) and \\(w \\in W\\) the id of a writer. We use \\(K\\) to denote the set of all possible keys. Also, with each transaction we associate a tag \\(t \\in \\mathbb{N}\\), which will help us define an order among the transactions.\n\n\\textbf{State Variables:} The state variables in writer, reader and server processes are as follows. \\(i\\) Any writer \\(w\\) has a counter \\(z\\) to keep track of the number of \\texttt{WRITE} transactions it has invoked so far, initially \\(0\\). \\(ii\\) The reader \\(r\\) has an ordered list \\(\\text{List}\\) of elements as \\((\\kappa, (b_1, \\cdots, b_k))\\), where \\(\\kappa \\in K\\) and \\((b_1, \\cdots, b_k) \\in \\{0, 1\\}^k\\). Initially, \\(\\text{List} = [(\\kappa^0, (1, \\cdots, 1))]\\), where \\(\\kappa^0 \\equiv (0, w_0)\\), where \\(w_0\\) is any place holder identifier string for writer id. The \\(\\text{List}\\) can be thought of as an array, with \\(0\\) as the starting index. \\(iii\\) Each server \\(s_i \\in S\\) there is a set variable \\(\\text{Vals}\\) with elements that are key-value pairs \\((\\kappa, v_i) \\in K \\times V_i\\). Initially, \\(\\text{Vals} = \\{(\\kappa^0, v_i^0)\\}\\).\n\n\\textbf{Writer steps:} The procedure \\texttt{WRITE}((\\(o_{i_1}, v_{i_1}\\), \\(o_{i_2}, v_{i_2}\\), \\(\\cdots, o_{i_p}, v_{i_p}\\)), for a \\texttt{WRITE} transaction, can be invoked at any writer \\(w\\), where \\(I = \\{i_1, i_2, \\cdots, i_p\\}\\) is any subset of \\(p\\) indices of \\([k]\\). We define the set \\(S_I \\triangleq \\{s_{i_1}, s_{i_2}, \\cdots, s_{i_p}\\}\\). This procedure consists of two consecutive phases: \\texttt{write-value} and \\texttt{inform-reader}. In the \\texttt{write-value phase}, \\(w\\) creates a key \\(\\kappa\\) as \\(\\kappa \\equiv (z + 1, w)\\); and also increments the local counter \\(z\\) by one. Then it sends \\((\\text{WRITE-VALUE}, (\\kappa, v_i))\\) to each server \\(s_i\\) in \\(S_I\\), and awaits ACKNOWLEDGES from each server in \\(S_I\\). After receiving ACKNOWLEDGES from each server in \\(S_I\\), \\(w\\) initiates the \\texttt{inform-reader} phase during which it sends \\((\\text{INFORM-READER}, (\\kappa, (b_1, \\cdots, b_k)))\\) to \\(r\\), where for any \\(i \\in [k]\\), \\(b_i\\) is a boolean variable, such that \\(b_i = 1\\) if \\(s_i \\in S_I\\), otherwise \\(b_i = 0\\). Essentially, such a \\((k + 1)\\)-tuple identifies the set of objects that are updated during that \\texttt{WRITE} transaction,\ni.e., if \\( b_i = 1 \\) then object \\( o_i \\) was updated during the execution of the WRITE transaction, otherwise \\( b_i = 0 \\). After \\( w \\) receives ACKNOWLEDGE from \\( r \\) it completes the WRITE.\n\n*Reader steps:* Note that we use the same notations for \\( I \\) and \\( S_I \\) as above for the set of indices and corresponding servers, possibly different across transactions. The procedure \\( \\text{READ}(o_1, o_2, \\ldots, o_p) \\), for any READ transaction, is initiated at reader \\( r \\), where \\( o_1, o_2, \\ldots, o_p \\) denotes the subset of objects \\( r \\) intends to read. This procedure consists of only one phase, read-value, of communication between the reader and the servers in \\( S_I \\). Here \\( r \\) sends the message \\( (\\text{READ-VALUE}, \\kappa) \\) to each server \\( s_i \\in S_I \\), where the \\( \\kappa \\) is the key in the tuple \\((\\kappa, (b_1, \\ldots, b_k))\\) in \\( \\text{List} \\) located at index \\( j' \\) such that \\( b_i = 1 \\) such that \\( i \\in I \\). After receiving the values \\( v_{i_1}, v_{i_2}, \\ldots, v_{i_p} \\) from all servers in \\( S_I \\), where \\( S_I \\triangleq \\{s_{i_1}, s_{i_2}, \\ldots, s_{i_p}\\} \\), the transaction completes by returning \\((v_{i_1}, \\ldots, v_{i_p})\\).\n\nNext, if reader \\( r \\) receives a message \\( (\\text{INFORM-READER}, (\\kappa, (b_1, \\ldots, b_k))) \\) from any writer \\( w \\), then \\( r \\) appends \\((\\kappa, (b_1, \\ldots, b_k))\\) to its \\( \\text{List} \\), and responds to \\( w \\) with ACKNOWLEDGE and \\( t_w = |\\text{List}| \\), i.e., number of elements in list \\( \\text{List} \\). The order of the elements in \\( \\text{List} \\) corresponds to the order the WRITE transactions, the order of the incoming INFORM-READER updates, as seen by the reader.\n\n*Server steps:* The server protocol consists of two procedures corresponding to the messages containing the tags WRITE-VALUE and READ-VALUE. The first procedure is used if a server \\( s_i \\) receives a message \\((\\text{WRITE-VALUE}, (\\kappa, v_i))\\) from a writer \\( w \\), it adds \\((\\kappa, v_i)\\) to its set variable \\( Vals \\) and sends ACKNOWLEDGE back to \\( w \\). The second procedure is used if \\( s_i \\) receives a message such as \\((\\text{READ-VALUE}, \\kappa_i)\\) from \\( r \\) then it responds back with \\( v_i \\) such that the pair \\((\\kappa_i, v_i)\\) is in its variable \\( Vals \\).\n\nThe following result states that algorithm \\( A \\) respects SNOW properties. Note that the liveness property of READ and WRITE transactions are a part of the SNOW properties. Consider any failure-free execution of algorithm \\( A \\). In the steps for the reader assume the quantity \\( t_r \\triangleq \\max_{1 \\leq j \\leq |\\text{List}|} \\{j : \\text{List}[j], b_i = 1 \\wedge i \\in I\\} \\), which is presented as a comment in the pseudo-code for \\( A \\). We associate with any transaction \\( \\phi \\) a tag \\( \\text{tag}(\\phi) \\) such that if \\( \\phi \\) is a WRITE \\( \\text{tag}(\\phi) = t_w \\), i.e., the value of \\( t_w \\) before the completion of the operation, and \\( \\text{tag}(\\phi) = t_r \\) when \\( \\phi \\) is a READ.\n\n**Theorem 6.1.** Any well-formed and fair execution of algorithm \\( A \\) is an wait-free implementation of transaction processing in the MWSR setting with for objects of type \\( O_T \\), consisting of objects \\( o_1, o_2, \\ldots, o_k \\) maintained by the servers \\( s_1, s_2, \\ldots, s_k \\), respectively; and it respects the SNOW properties and WRITE transactions are live.\n\n**Proof.** Below we show that \\( A \\) satisfies the SNOW properties.\n\n*\\( S \\) property:* Let \\( \\beta \\) be any fair execution of \\( A \\) and suppose all clients in \\( \\beta \\) behave in a well-formed manner. Suppose \\( \\beta \\) contains no incomplete transactions and let \\( \\Pi \\) be the set of transactions in \\( \\beta \\). We define an irreflexive partial ordering \\( (\\prec) \\) among the transactions in \\( \\Pi \\) as follows: if \\( \\phi \\) and \\( \\pi \\) are any two distinct transactions in \\( \\Pi \\) then we say \\( \\phi \\prec \\pi \\) if either (i) \\( \\text{tag}(\\phi) < \\text{tag}(\\pi) \\) or (ii) \\( \\text{tag}(\\phi) = \\text{tag}(\\pi) \\) and \\( \\phi \\) is a WRITE and \\( \\pi \\) is a READ. We will prove the \\( S \\) (strict-serializability) property of \\( A \\) by proving that the properties \\( P1, P2, P3 \\) and \\( P4 \\) of Lemma 5.1 hold for \\( \\beta \\).\n\n*\\( P1: \\) If \\( \\pi \\) is a READ then since all READS are invoked by a single reader \\( r \\) and in a well-formed manner, therefore, there cannot be an infinite number of READS such that they all precede \\( \\pi \\) (w.r.t \\( \\prec \\)). Now, suppose \\( \\pi \\) is a WRITE. Clearly, from an inspection of the algorithm, \\( \\text{tag}(\\pi) \\in \\mathbb{N} \\). From inspection of the algorithm, each WRITE increases the size of \\( \\text{List} \\), and the value of the tags are defined by the size of \\( \\text{List} \\). Therefore, there can be at most a finite number of WRITES such that can precede \\( \\pi \\) (w.r.t. \\( \\prec \\)) in \\( \\beta \\).\n\n*\\( P2: \\) Suppose \\( \\phi \\) and \\( \\pi \\) are any two transactions in \\( \\Pi \\), such that, \\( \\pi \\) begins after \\( \\phi \\) completes.\nThen we show that we cannot have $\\pi < \\phi$. Now, we consider four cases, depending on whether $\\phi$ and $\\pi$ are READS or WRITES.\n\n(a) $\\phi$ and $\\pi$ are WRITES invoked by writers $w_\\phi$ and $w_\\pi$, respectively. Since the size of $List$, in $r$, grows monotonically with each WRITE hence $w_\\pi$ receives the tag at least as high as $tag(\\phi)$, so $\\pi \\not< \\phi$.\n\n(b) $\\phi$ is a WRITE, $\\pi$ is a READ transactions invoked by writer $w_\\phi$ and $r$, respectively. Since the size of $List$, in $r$, grows monotonically, and because $w_\\pi$ invokes $\\pi$ after $\\phi$ completes hence $tag(\\pi)$ is at least as high as $tag(\\phi)$, so $\\pi \\not< \\phi$.\n\n(c) $\\phi$ and $\\pi$ are READS invoked by reader $r$. Since the size of $List$, in $r$, grows monotonically, hence $w_\\pi$ invoked $\\pi$ after $\\phi$ completes hence $tag(\\pi)$ is at least as high as $tag(\\phi)$, so $\\pi \\not< \\phi$.\n\n(d) $\\phi$ is a READ, $\\pi$ is a WRITE invoked by reader $r$ and $w_\\pi$, respectively. This case is simple because new values are added to $List$ only by writers, and $tag(\\pi)$ is at least as large as the tag of $\\phi$ and hence $\\pi \\not< \\phi$.\nP3: This is clear by the fact that any WRITE transaction always creates a unique tag and all tags are totally ordered since they all belong to $\\mathbb{N}$.\n\n$P4$: Consider a READ $\\rho$ as $READ(o_{i_1}, o_{i_2}, \\ldots, o_{i_q})$, in $\\beta$. Let the returned value from $\\rho$ be $v = (v_{i_1}, v_{i_2}, \\ldots, v_{i_q})$ such that $1 \\leq i_1 < i_2 < \\cdots < i_q \\leq k$, where value $v_{i_j}$ corresponds to $o_{i_j}$. Suppose $tag(\\rho) \\in \\mathbb{N}$ was created during some WRITE transaction, say $\\phi$, i.e., $\\phi$ is the WRITE that added the elements in index $(tag(\\rho) - 1)$ of $List$. Note that element in index 0 contains the initial value. Now we consider two cases:\n\nCase $tag(\\rho) = 1$. We know that it corresponds the initial default value $v_i^0$ at each sub-object $o_i$, and this equates to $\\rho$ returning the default initial value for each sub-object.\n\nCase $tag(\\rho) > 1$. Then we argue that there exists no WRITE transaction, say $\\pi$, that updated object $o_{i_j}$, in $\\beta$, such that, $\\pi \\neq \\phi$ and $\\rho$ returns values written by $\\pi$ and $\\phi < \\pi < \\rho$. Suppose we assume the contrary, which means $tag(\\phi) < tag(\\pi) < tag(\\rho)$. The latter implies $tag(\\phi) = tag(\\pi)$ which is not possible because this contradicts the fact that for any two distinct WRITES $tag(\\phi) \\neq tag(\\pi)$ in any execution of $A$.\n\n$N$ property: By inspection of algorithm $A$ for the response steps of the servers to the reader.\n\n$O$ property: By inspection of the read-value phase: it consists of one round of communication between the reader and the servers, where the servers send only one version of the value of the object it maintains.\n\n$W$ property: By inspection of the WRITE transaction steps, and that writers always get to complete the transactions they invoke. \\hfill $\\Box$\n\nNote that the above theorem holds in the presence of any writer crashes.\n\n7 SNoW for MWMR setting\n\nIn this section, we present algorithm $B$ for transaction processing in the multiple-writers multi-reader (MWMR) setting and show that its execution satisfies SNoW properties, where “o” means a READ may consist of more than one round trip of communications between the reader and the servers. We denote the type of object that satisfies the SNoW properties by $\\hat{o}$.\n\nWe assume the contrary, which means $tag(\\phi) < tag(\\pi) < tag(\\rho)$. The latter implies $tag(\\phi) = tag(\\pi)$ which is not possible because this contradicts the fact that for any two distinct WRITES $tag(\\phi) \\neq tag(\\pi)$ in any execution of $A$.\n\nWe assume the contrary, which means $tag(\\phi) < tag(\\pi) < tag(\\rho)$. The latter implies $tag(\\phi) = tag(\\pi)$ which is not possible because this contradicts the fact that for any two distinct WRITES $tag(\\phi) \\neq tag(\\pi)$ in any execution of $A$.\n\n$\\bar{O}_7$. The steps of the algorithm for the writers, readers and the servers are presented in Fig.5. We assume there is a set of readers $\\mathcal{R}$ and a set of $k \\geq 1$ servers, $\\mathcal{S}$, with ids $s_1, s_2, \\ldots, s_k$ that stores the objects $o_1, o_2, \\ldots, o_k$, respectively. We define key $\\kappa$ is defined as a pair $(z, w)$, where $z \\in \\mathbb{N}$ and $w \\in \\mathcal{W}$ the id of a writer. We use $\\mathcal{K}$ to denote the set of all possible keys. Like in algorithm $A$ from Section 6 also in $B$, the keys are used to uniquely identify each transaction. Also, with each transaction we associate a tag $t \\in \\mathbb{N}$.\n\nIn algorithm $B$, we designate one of the servers as the coordinator, we denote as $s^*$, for the transactions. Essentially, the coordinator $s^*$ is used to maintain the order of the WRITEs and the objects that are updated during the WRITE in the variable $List$. Note that in a system, where there are many objects different objects may be use different servers as coordinators based on some load-balancing rule.\n\nState Variables: Each of the writers and servers maintain a set of state variables as follows: (i) At any writer $w$, there is a counter $z$ to keep track of the number of WRITE transactions the writer has invoked, initially 0. (ii) At any server, $s_i$, for $i \\in [k]$, there is a set variable $Vals$ with elements that are key-value pairs $(\\kappa, v_i) \\in \\mathcal{K} \\times \\mathcal{V}$. Initially, $Vals = \\{(\\kappa^0, v_i^0)\\}$. A server also contains an ordered list variable $List$ of elements as $(\\kappa, (b_1, \\ldots, b_k))$, where $\\kappa \\in \\mathcal{K}$ and $(b_1, \\ldots, b_k) \\in \\{0, 1\\}^k$. \n\n33\nFig. 5 The protocol for any writer $w$, reader $r$ or server $s_i$ for algorithm B.\n\nAt writer $w$\n\nState Variables:\n$z \\in \\mathbb{N}$, initially 0\n\n$\\text{WRITE}((i_1,v_{i_1}), (i_2,v_{i_2}), \\ldots, (i_p,v_{i_p}))$ \n\n$2:$ $I \\triangleq \\{i_1, i_2, \\ldots, i_p\\}$\n\n$\\text{write-value}$\n\n$4:$ $\\kappa \\leftarrow (z + 1, w); z \\leftarrow z + 1$\n\nfor $i \\in I$ do\n\n$6:$ Send $\\text{write-value}, (\\kappa, v_i)$ to server $s_i$\n\nAwait $\\text{ACKNOWLEDGE}$ from servers in $S_I$.\n\nAt reader $r$\n\n$\\text{READ}(o_{i_1}, o_{i_2}, \\ldots, o_{i_p})$\n\n$I \\triangleq \\{i_1, i_2, \\ldots, i_p\\}$\n\n$18:$ $\\text{get-tag-array}$\n\nSend $(\\text{get-tag-array})$ to server $s^*$\n\n20: Receive response $(t_r, (\\kappa_1,\\kappa_2, \\ldots, \\kappa_k))$ from $s^*$\n\nAt server $s_i$ for any $i \\in [k]$\n\nState Variables:\n$\\text{Vals} \\subseteq K \\times \\mathbb{N}$, initially $\\{(0, v_i^0)\\}$\n$\\text{List}$, a list of $K \\times \\{0,1\\}^k$, initially $[(\\kappa^0, (1, \\ldots, 1))]$\n\n$28:$ \\textbf{On recv} $(\\text{write-value}, (\\kappa, v))$ from $w$:\n\n$\\text{Vals} \\leftarrow \\text{Vals} \\cup \\{(\\kappa, v)\\}$\n\nSend $\\text{ACKNOWLEDGE}$ to writer $w$.\n\n$30:$ \\textbf{On recv} $(\\text{write-value}, (\\kappa, v))$ from $w$:\n\n$32:$ \\textbf{On recv} $(\\text{UPDATE-COORD}, (\\kappa, (b_1, \\ldots, b_k)))$ from $w$:\n\n$34:$ \\textbf{Send} $(\\text{ACKNOWLEDGE}, \\text{tag})$ to $w$\n\nOn $r$:\n\nOn $r$:\n\nInitially, $\\text{List} = [(\\kappa^0, (1, \\ldots, 1)]$, where $\\kappa^0 \\equiv (0, w_0)$, where $w_0$ is any placeholder identifier string for writer id. The elements in $\\text{List}$ can be identified with an index, e.g., $\\text{List}[0] = (\\kappa^0, (1, \\ldots, 1))$. Essentially, a $(k+1)$-tuple $(\\kappa, (b_1, \\ldots, b_k))$ in $\\text{List}$ corresponds to a $\\text{WRITE}$ transaction and identifies the set of objects that are updated during the $\\text{WRITE}$ transaction, i.e., if $b_i = 1$ then object $o_i$ was updated during the execution of the $\\text{WRITE}$ transaction, otherwise $b_i = 0$. \n\nWriter steps: A $\\text{WRITE}$ transaction that is meant to update a list of $p$ objects $o_{i_1}, o_{i_2}, \\ldots, o_{i_p}$ with values $v_{i_1}, v_{i_2}, \\ldots, v_{i_p}$, respectively, is invoked at $w$ via the procedure $\\text{WRITE}((o_{i_1}, v_{i_1}), (o_{i_2}, v_{i_2}), \\ldots, (o_{i_p}, v_{i_p}))$. We use the notations: $I \\triangleq \\{i_1, i_2, \\ldots, i_p\\}$ and $S_I \\triangleq \\{s_{i_1}, s_{i_2}, \\ldots, s_{i_p}\\}$. This procedure consists of two phases: $\\text{write-value}$ and $\\text{update-coord}$. During the $\\text{write-value}$ phase, $w$ creates a new key $\\kappa$ as $\\kappa \\equiv (z + 1, w)$, where $w$ is the identity of the writer; and also increments the local counter $z$ by one. Then $w$ sends $(\\text{WRITE}-\\text{VALUE}, (\\kappa, v_i))$ to each server in $S_I$, and awaits $\\text{ACKNOWLEDGE}$ from all servers in $S_I$. After receiving $\\text{ACKNOWLEDGE}$ from all servers in $S_I$, $w$ initiates the $\\text{update-coord}$ phase where it sends $(\\text{UPDATE-COORD}, (\\kappa, (b_1, \\ldots, b_k)))$ to $s^*$, where for any $i \\in [k]$, $b_i = 1$ if $s_i \\in S_I$, otherwise $b_i = 0$, and completes the procedure after it receives a $\\text{ACKNOWLEDGE}$ message from $s^*$. After receiving message as $(\\text{ACKNOWLEDGE}, t_w)$, $w$ completes the $\\text{WRITE}$. \n\n34\nReader steps: Note that we use the same notations for \\( I \\) and \\( S_f \\) as above by the set of indices are not necessarily similar across different transactions. The procedure \\( \\text{READ}(o_{i_1}, o_{i_2}, \\ldots, o_{i_p}) \\) can be initiated by some reader \\( r \\), as a READ transaction, intending to read the values of subset \\( o_{i_1}, o_{i_2}, \\ldots, o_{i_p} \\) of the objects. The procedure consists of two consecutively executed phases of communication rounds between the \\( r \\) and the servers, viz., \\text{get-tag-array} and \\text{read-value}. During the phase \\text{get-tag-array}, \\( r \\) sends \\( s^* \\) the message \\text{GET-TAG-ARRAY} requesting the list of the latest added keys for each object. Once \\( r \\) receives a list of tags, such as, \\((t_r, (\\kappa_1, \\kappa_2, \\ldots, \\kappa_k))\\) from \\( s^* \\) the phase completes. In the subsequence phase, \\text{read-value}, \\( r \\) requests each server \\( s_i \\) in \\( S_f \\) by sending the message \\((\\text{READ-VALUE}, \\kappa_i)\\). After receiving the values \\( v_{i_1}, v_{i_2}, \\ldots, v_{i_p} \\) from the servers in \\( S_f \\), \\( r \\) completes the transaction by returning the tuple of values \\((v_{i_1}, \\ldots, v_{i_p})\\).\n\nServer steps: When a server \\( s_i \\) receives a message of type \\((\\text{WRITE-VALUE}, (\\kappa, v_i))\\) from a writer \\( w \\) then it adds \\((\\kappa, v_i)\\) to its set variable \\( Vals \\) and sends \\text{ACKNOWLEDGE} back to \\( w \\).\n\nIf the coordinator \\( s^* \\), receives \\((\\text{UPDATE-COORD}, (\\kappa, (b_1, \\ldots, b_k)))\\) from writer \\( w \\), then it appends \\((\\kappa, (b_1, \\ldots, b_k))\\) to its \\( List \\), and responds with \\text{ACKNOWLEDGE} and \\( t_w \\) (set to be the number of elements in the local list \\( List \\)) to \\( w \\). The order of the elements in \\( List \\) corresponds to the order the \\text{WRITE} transactions, the order of the incoming \\text{UPDATE-COORD} updates, as seen by \\( s^* \\).\n\nAgain, when \\( s^* \\) receives the message \\text{GET-TAG-ARRAY} from \\( r \\) it responds with a message \\((\\kappa_1, \\ldots, \\kappa_k)\\) such that for each \\( i \\in [k], \\kappa_i \\) is the key part of the \\((k + 1)\\)-tuple that was modified last, i.e., \\( \\kappa_i = List[j^*].\\kappa \\) such that \\( j^* \\triangleq \\max\\{j : List[j].b_i = 1\\}, \\) and \\( t_r, t_r \\triangleq \\max_{1 \\leq j \\leq |List|}\\{j : List[j].b_i = 1 \\wedge i \\in I\\}\\).\n\nIf any server \\( s_i \\) receives a message \\((\\text{READ-VALUE}, \\kappa)\\) from a reader \\( r \\) then it responds to \\( r \\) with the value \\( v_i \\) corresponding to key with value \\( \\kappa \\) in \\( Vals \\).\n\nNote the the following result states that algorithm \\( B \\) respects SNoW property. Consider any failure-free and fair execution of algorithm \\( B \\). For the purpose of proving the \\( S \\) property, for every transaction transaction \\( \\phi \\) in an execution of \\( B \\) we associate a tag \\( tag(\\phi) \\) as described below. If \\( \\phi \\) is a \\text{WRITE (READ)} then \\( tag(\\phi) \\) is the value of the variable \\( t_w \\) (\\( t_r \\)) immediately before the operation completes.\n\n**Theorem 7.1.** Any well-formed and fair execution of algorithm \\( B \\) is an implementation of an object of type \\( \\tilde{O}_T \\) in the MWMR setting, with no client-to-client communication, comprising of objects \\( o_1, o_2, \\ldots, o_k \\) stored in servers \\( s_1, s_2, \\ldots, s_k \\), respectively; and it satisfies the SNoW properties.\n\n**Proof.** Below we show that algorithm \\( B \\) satisfies the SNoW properties.\n\n**S property:** Let \\( \\beta \\) be any fair execution of \\( B \\) and suppose all clients in \\( \\beta \\) behave in an well-formed manner. Suppose \\( \\beta \\) contains no incomplete transactions and let \\( \\Pi \\) be the set of transactions in \\( \\beta \\). We define an irreflexive partial ordering (\\( \\prec \\)) in \\( \\Pi \\) as follows: if \\( \\phi \\) and \\( \\pi \\) are any two distinct transactions in \\( \\Pi \\) then we say \\( \\phi \\prec \\pi \\) if either \\( i \\) tag(\\( \\phi \\)) \\( < \\) tag(\\( \\pi \\)) or \\( ii \\) tag(\\( \\phi \\)) = tag(\\( \\pi \\)) and \\( \\phi \\) is a WRITE and \\( \\pi \\) is a READ. Below we prove the \\( S \\) property of \\( B \\) by showing that properties \\( P1, P2, P3 \\) and \\( P4 \\) of Lemma \\ref{lemma:5.1} hold for \\( \\beta \\).\n\n**P1:** Clearly, from an inspection of the algorithm, \\( tag(\\pi) \\in \\mathbb{N} \\). From inspection of the algorithm, each WRITE increases the size of \\( List \\), and the value of the tags are defined by the size of \\( List \\). Therefore, there can be at most a finite number of writes such that can precede \\( \\pi \\) (w.r.t. \\( \\prec \\)) in \\( \\beta \\). On the other hand, if \\( \\pi \\) is a READ then since all READS are invoked by readers in a well-formed manner, and there are only finite number of readers therefore, there cannot be an infinite number of READS such that they all precede \\( \\pi \\) (w.r.t. \\( \\prec \\)).\n\n**P2:** Suppose \\( \\phi \\) and \\( \\pi \\) are any two transactions in \\( \\Pi \\), such that, \\( \\pi \\) begins after \\( \\phi \\) completes.\nThen we show that we cannot have $\\pi < \\phi$. Now, we consider four cases, depending on whether $\\phi$ and $\\pi$ are reads or writes.\n\n(a) $\\pi$ and $\\phi$ are writes invoked by writers $w_\\phi$ and $w_\\pi$, respectively. Since the size of $List$, in $s^*$ grows monotonically due to each write hence $w_\\pi$ receives the tag from $s^*$ at least as high as $tag(\\phi)$, so $\\pi \\not< \\phi$.\n\n(b) $\\pi$ is a read, $\\phi$ is a write invoked by reader $r_\\pi$ and writer $w_\\phi$, respectively. Since the size of $List$, in $s^*$, grows monotonically, because $r_\\pi$ invokes $\\pi$ after $\\phi$ completes hence $tag(\\pi)$ is at least as high as $tag(\\phi)$, so $\\pi \\not< \\phi$.\n\n(c) $\\pi$ and $\\phi$ are both reads invoked by readers $r_\\pi$ and $r_\\phi$, respectively. Since the size of $List$, in $s^*$, grows monotonically, because $w_\\pi$ invokes $\\pi$ after $\\phi$ completes hence $tag(\\pi)$ is at least as high as $tag(\\phi)$, so $\\pi \\not< \\phi$.\n\n(d) $\\pi$ is a write, $\\phi$ is a read invoked by writer $w_\\pi$ and reader $r_\\phi$, respectively. This case is simple because new values are added to $List$, in $s^*$, only by writers, and $tag(\\pi)$ is at least as large as the tag of $\\phi$ and hence $\\pi \\not< \\phi$.\n\n$P3$: This is from the fact that any write transaction always creates a unique tag and all tags are totally ordered since they all belong to $\\mathbb{N}$.\n\n$P4$: Consider a read $\\rho$ as $READ(o_{i_1}, o_{i_2}, \\cdots, o_{i_q})$, in $\\beta$. Let the returned value from $\\rho$ be $v \\equiv (v_{i_1}, v_{i_2}, \\cdots, v_{i_q})$ such that $1 \\leq i_1 < i_2 < \\cdots < i_q \\leq k$, where value $v_{i_j}$ corresponds to $o_{i_j}$. Suppose $tag(\\rho) \\in \\mathbb{N}$ was created during some write transaction, say $\\phi$, i.e., $\\phi$ is the write that added the elements in index $(tag(\\rho) - 1)$ of $List$ at the coordinator $s^*$. Note that element in index 0 contains the initial value. Now we consider two cases:\n\nCase $tag(\\rho) = 1$. We know that it corresponds the initial default value $v^0_i$ at each sub-object $o_i$, and this equates to $\\rho$ returning the default initial value for each sub-object.\n\nCase $tag(\\rho) > 1$. Then we argue that there exists no write transaction, say $\\pi$, that updated object $o_{i_j}$, in $\\beta$, such that, $\\pi \\not< \\phi$ and $\\rho$ returns values written by $\\pi$ and $\\phi < \\pi < \\rho$. Suppose we assume the contrary, which means $tag(\\phi) < tag(\\pi) < tag(\\rho)$. The latter implies $tag(\\phi) = tag(\\pi)$ which is not possible because this contradicts the fact that for any two distinct writes $tag(\\phi) \\neq tag(\\pi)$ in any execution of $B$.\n\n$N$, $o$ and $W$ properties: Evident from an inspection of the algorithm.\n\n\\[\\square\\]\n\n8 SN\\={W} for MWMR setting\n\nIn this section, we present algorithm $C$ for transaction processing in the \\textit{multiple-writers multi-reader} (MWMR) setting and show that its execution satisfies SN\\={W} properties, where \\textit{“\\={W}”} means a read consists of only one round trip of communications between the reader and the servers but the servers may respond with multiple versions of the data. We denote the type of object that satisfies the SN\\={W} properties by $\\overline{O}_T$. The steps of the algorithm for the writers, readers and the servers are presented in Fig[6]. We assume there is a set of writers $W$, a set of readers $R$ and a set of $k \\geq 1$ servers, $S$, with ids $s_1, s_2 \\cdots s_k$ that stores the objects $o_1, o_2, \\cdots, o_k$, respectively. We define key $\\kappa$ is defined as a pair $(z, w)$, where $z \\in \\mathbb{N}$ and $w \\in W$ the id of a writer. We use $K$ to denote the set of all possible keys. As in the algorithms presented in Section [6] and [7] the keys are used to uniquely identify each transaction. Also, with each transaction we associate a tag $t \\in \\mathbb{N}$.\n\n36\nFig. 6 The protocol for any writer \\( w \\), reader \\( r \\) or server \\( s_i \\) for algorithm \\( B \\).\n\nAt writer \\( w \\)\n\nState Variables:\n\\( z \\in \\mathbb{N} \\), initially 0\n\n\\[ \\text{WRITE}((i_1, v_{i_1}), (i_2, v_{i_2}), \\ldots, (i_p, v_{i_p})) \\]\n\n2: \\( I \\triangleq \\{i_1, i_2, \\ldots, i_p\\} \\)\n\nwrite-value:\n\n4: \\( \\kappa \\leftarrow (z + 1, w) \\); \\( z \\leftarrow z + 1 \\)\n\nfor \\( i \\in I \\) do\n\n6: Send WRITE-VALUE, \\((\\kappa, v_{i})\\) to server \\( s_i \\)\n\nAwait ACKNOWLEDGE from servers in \\( S_I \\).\n\nAt reader \\( r \\)\n\nREAD(\\( o_{i_1}, o_{i_2}, \\ldots, o_{i_p} \\))\n\n\\( I \\triangleq \\{i_1, i_2, \\ldots, i_p\\} \\)\n\n18: read-values-and-tags\n\nSend (GET-TAG-ARRAY) to server \\( s^* \\)\n\nAt server \\( s_i \\) for any \\( i \\in [k] \\)\n\nState Variables:\n\\( Vals \\subset K \\times V_i \\), initially \\( \\{(\\kappa^0, v^0_i)\\} \\)\n\nList, a list of \\( K \\times \\{0, 1\\}^k \\), initially \\( \\{(\\kappa^0, (1, \\ldots, 1))\\} \\)\n\nOn recv (WRITE-VALUE, \\((\\kappa, v)\\)) from \\( w \\):\n\n28: \\( Vals \\leftarrow Vals \\cup \\{(\\kappa, v)\\} \\)\n\nSend ACKNOWLEDGE to writer \\( w \\).\n\nOn recv (UPDATE-COORD, \\((\\kappa, (b_1, \\ldots, b_k))\\)) from \\( w \\):\n\n30: \\( List \\leftarrow List \\bigoplus (\\kappa, (b_1, \\ldots, b_k)) \\bigoplus \\) for append\n\n32: \\( \\text{tag} \\leftarrow |List| \\bigoplus |\\cdot| \\) size of the list\n\n34: On recv (READ-VALUES) from \\( r \\):\n\nSend \\( Vals \\) to \\( r \\)\n\n\\(/^* \\) used only by \\( s^* */^*\n\n36: On recv GET-TAG-ARRAY from \\( r \\):\n\n\\( \\text{for } i \\in [k] \\text{ do} \\)\n\n38: \\( j^* \\leftarrow \\max\\{j : List[j].b_i = 1\\} \\)\n\n\\( \\kappa_i = List[j^*].\\kappa \\)\n\n40: \\( t_r \\leftarrow \\max\\{j \\leq |List| : \\{j : List[j].b_i = 1 \\wedge i \\in I\\} \\}\n\nSend \\((t_r, (\\kappa_1, \\kappa_2, \\ldots, \\kappa_k))\\) to \\( r \\)\n\nIn algorithm \\( C \\), we designate one of the servers as the coordinator, we denote as \\( s^* \\), for the transactions. In addition to managing some object, the server \\( s^* \\) is used to maintain the order of the writes and the objects that are updated during the write in the variable \\( List \\). In any system, where there are many objects different objects may be use different servers as coordinators based on some load-balancing rule.\n\nState Variables: The state variables in algorithm \\( C \\) is similar to those of algorithm \\( B \\), therefore, we omit here. Writer steps: The steps of a write transaction is similarly to algorithm \\( B \\), therefore, we omit here.\n\nReader steps: The procedure READ(\\( o_{i_1}, o_{i_2}, \\ldots, o_{i_p} \\)) can be initiated by some reader \\( r \\), as a read transaction, intending to read the values of subset \\( o_{i_1}, o_{i_2}, \\ldots, o_{i_p} \\) of the objects. We use the notations: \\( I \\triangleq \\{i_1, i_2, \\ldots, i_p\\} \\) and \\( S_I \\triangleq \\{s_{i_1}, s_{i_2}, \\ldots, s_{i_p}\\} \\). The procedure consists of only one phase of communication round between the \\( r \\) and the servers, called read-values-and-tags. During the phase read-values-and-tags, \\( r \\) sends \\( s^* \\) the message GET-TAG-ARRAY requesting the list of the latest added keys for each object, and also sends requests (READ-VALUES) each server \\( s_i \\) in \\( S_I \\). Note that if \\( s^* \\) is also one of the servers in \\( S_I \\) then the GET-TAG-ARRAY and READ-VALUES messages to \\( s^* \\) can be combined to create one message; however, we keep them separate for clarity of presentation. Once \\( r \\) receives a list of tags, such as, \\((t_r, (\\kappa_1, \\kappa_2, \\ldots, \\kappa_k))\\) from \\( s^* \\) and the set of \\( Vals_i \\) from each \\( s_i \\in S_I \\)\nthen \\( r \\) returns the values \\( v_{i_1}, v_{i_2}, \\ldots, v_{i_p} \\) such that \\((\\kappa_j, v_j) \\in \\text{Vals}_j, j \\in \\{1, \\ldots, p\\}\\), and completes the read.\n\nServer steps: When a server \\( s_i \\) receives a message of type \\( \\text{WRITE-VALUE}, (\\kappa, v_i) \\) from a writer \\( w \\); or if the coordinator \\( s^* \\), receives \\( \\text{UPDATE-COORD}, (\\kappa, (b_1, \\ldots, b_k)) \\) from writer \\( w \\) or receives a message as \\( \\text{GET-TAG-ARRAY} \\) from \\( r \\) the steps are similar to their counterparts in algorithm \\( B \\). Therefore, we omit them. On the other hand, if any server \\( s_i \\) receives a message \\( \\text{READ-VALUES} \\) from a reader \\( r \\) then it responds to \\( r \\) with the entire set of values, i.e., \\( \\text{Vals} \\).\n\nNote the the following result states that algorithm \\( C \\) respects SN\\text{NoW} property. Consider any failure-free and fair execution of algorithm \\( C \\). For the purpose of proving the \\( S \\) property, for every transaction \\( \\phi \\) in an execution of \\( C \\) we associate a tag \\( \\text{tag}(\\phi) \\) as described below. If \\( \\phi \\) is a WRITE (READ) then \\( \\text{tag}(\\phi) \\) is the value of the variable \\( t_w \\) \\( (t_r) \\) immediately before the operation completes.\n\n**Theorem 8.1.** Any well-formed and fair execution of algorithm \\( C \\) is an implementation of an object of type \\( \\bar{O}_T \\) in the MWMR setting, with no client-to-client communication, comprising of objects \\( o_1, o_2, \\ldots, o_k \\) stored in servers \\( s_1, s_2, \\ldots, s_k \\), respectively; and it satisfies the SN\\text{NoW} properties.\n\n**Proof.** Below we show that algorithm \\( C \\) satisfies the SN\\text{NoW} properties.\n\n**S property:** Let \\( \\beta \\) be any fair execution of \\( B \\) and suppose all clients in \\( \\beta \\) behave in an well-formed manner. Suppose \\( \\beta \\) contains no incomplete transactions and let \\( \\Pi \\) be the set of transactions in \\( \\beta \\). We define an irreflexive partial ordering \\((\\prec)\\) in \\( \\Pi \\) as follows: if \\( \\phi \\) and \\( \\pi \\) are any two distinct transactions in \\( \\Pi \\) then we say \\( \\phi \\prec \\pi \\) if either \\((i)\\) \\( \\text{tag}(\\phi) < \\text{tag}(\\pi) \\) or \\((ii)\\) \\( \\text{tag}(\\phi) = \\text{tag}(\\pi) \\) and \\( \\phi \\) is a WRITE and \\( \\pi \\) is a READ. Below we prove the \\( S \\) property of \\( B \\) by showing that properties \\( P_1, P_2, P_3 \\) and \\( P_4 \\) of Lemma 5.1 hold for \\( \\beta \\). The properties \\( P_1-P_4 \\) can be proved to hold in a manner very similar to algorithm \\( B \\) (Section 7). Therefore, we avoid repeating them.\n\n**N, \\bar{o} and W properties:** Evident from an inspection of the algorithm. \\( \\square \\)\n\n**References**\n\n\n"}}},{"rowIdx":79,"cells":{"id":{"kind":"string","value":"c5cf1c1fae32d12ea99124115500364dbaee7224"},"text":{"kind":"string","value":"Freeway®\nTransport Subsystem Interface\nReference Guide\nDC 900-1386D\nContents\n\nList of Figures .................................................. 7\nList of Tables .................................................. 9\nPreface ................................................................ 11\n\n1 Overview ................................................................ 17\n 1.1 Product Overview .............................................. 17\n 1.1.1 Freeway Server ............................................. 18\n 1.1.2 Embedded ICP .............................................. 18\n 1.2 Freeway Client-Server Environment Using TSI .......... 22\n 1.2.1 Establishing Freeway Internet Addresses ............... 23\n 1.2.2 Defining the TSI Configuration ......................... 23\n 1.2.3 Establishing a Freeway TSI Connection ................. 24\n 1.2.4 Exchanging Data through the Freeway Message Multiplexer .... 24\n 1.2.5 Closing a Freeway Session ............................ 24\n 1.3 TSI Overview and Features ................................ 25\n\n2 TSI Concepts ..................................................... 29\n 2.1 Configuration in the Freeway Environment ............... 29\n 2.2 Blocking versus Non-blocking I/O .......................... 30\n 2.2.1 I/O Completion Handler for Non-Blocking I/O ......... 31\n 2.3 Buffer Management ........................................... 31\n 2.3.1 Overview of the Freeway System Buffer Relationships .... 32\n 2.3.1.1 Example Calculation to Change ICP, Client, and Server Buffer Sizes .... 33\n 2.3.2 Client TSI Buffer Configuration .......................... 35\n 2.3.2.1 TSI Buffer Pool Definition .......................... 36\nFreeway Transport Subsystem Interface Reference Guide\n\n2.3.2.2 Connection-Specific Buffer Definition .................................. 38\n2.3.2.3 TSI Buffer Size Negotiation ............................................. 39\n2.3.3 Server TSI Buffer Configuration ........................................... 40\n2.3.4 Buffer Allocation and Release ............................................. 40\n2.3.5 Cautions for Changing Buffer Sizes ...................................... 41\n2.3.6 Using Your Own Buffers ................................................... 41\n2.3.7 Buffer Management (Client versus Server-Resident Applications) ... 43\n2.4 System Resource Requirements ............................................... 44\n 2.4.1 Signal Processing ......................................................... 45\n\n3 TSI Configuration\n 3.1 Configuration Process Overview ............................................ 47\n 3.2 Introduction to TSI Configuration ......................................... 50\n 3.2.1 TSI Configuration Language ......................................... 50\n 3.2.2 Rules of the TSI Configuration File ................................ 51\n 3.2.3 Binary Configuration File Management ................................ 52\n 3.2.4 On-line Configuration File Processing .............................. 52\n 3.3 TSI Connection Definition ................................................... 53\n 3.3.1 Parameters for the \"main\" Definition ................................ 54\n 3.3.2 Parameters for the Connection Definition (Non-transport Specific) 56\n 3.3.3 Parameters for Connection Definition (TCP/IP Socket Transport) 58\n 3.3.4 Parameters for Connection Definition (Shared-Memory Transport) 59\n 3.4 Example TSI Configurations .................................................. 60\n 3.4.1 TCP/IP Socket Transport Interface .................................. 60\n 3.4.2 Shared-Memory Transport Interface (VxWorks Only) ............ 62\n 3.5 Protagate's Freeway Server TSI Configuration .......................... 65\n 3.6 Miscellaneous TSI Configuration Details ................................ 67\n 3.6.1 TSI Configuration Error Messages .................................. 67\n 3.6.2 Protagate Definition Language (PDL) Grammar ..................... 69\n\n4 TSI Functions\n 4.1 Overview of TSI Functions .................................................. 71\n 4.1.1 TSI Error Handling ................................................... 71\n 4.1.2 Categories of TSI Functions ......................................... 72\n 4.1.2.1 Summary of TSI Functions .................................... 73\n 4.1.3 TSI Data Structures ................................................... 76\n\nDC 900-1386D\n## Contents\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>4.1.3.1 TSI System Configuration</td>\n<td>76</td>\n</tr>\n<tr>\n<td>4.1.3.2 TSI Connection Status</td>\n<td>78</td>\n</tr>\n<tr>\n<td>4.1.3.3 TSI Connection Definition List</td>\n<td>78</td>\n</tr>\n<tr>\n<td>4.2 tBufAlloc</td>\n<td>80</td>\n</tr>\n<tr>\n<td>4.3 tBufFree</td>\n<td>82</td>\n</tr>\n<tr>\n<td>4.4 tConnect</td>\n<td>84</td>\n</tr>\n<tr>\n<td>4.5 tDisconnect</td>\n<td>88</td>\n</tr>\n<tr>\n<td>4.6 tInit</td>\n<td>91</td>\n</tr>\n<tr>\n<td>4.7 tListen</td>\n<td>95</td>\n</tr>\n<tr>\n<td>4.8 tPoll</td>\n<td>100</td>\n</tr>\n<tr>\n<td>4.9 tPost</td>\n<td>107</td>\n</tr>\n<tr>\n<td>4.10 tRead</td>\n<td>109</td>\n</tr>\n<tr>\n<td>4.11 tSyncSelect</td>\n<td>114</td>\n</tr>\n<tr>\n<td>4.12 tTerm</td>\n<td>117</td>\n</tr>\n<tr>\n<td>4.13 tWrite</td>\n<td>120</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>A TSI Common Error Codes</td>\n<td>125</td>\n</tr>\n<tr>\n<td>A.1 Internal Error Codes</td>\n<td>125</td>\n</tr>\n<tr>\n<td>A.2 Command-Specific Error Codes</td>\n<td>137</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>B UNIX, VxWorks, and VMS I/O</td>\n<td>143</td>\n</tr>\n<tr>\n<td>B.1 UNIX Environment</td>\n<td>143</td>\n</tr>\n<tr>\n<td>B.1.1 Blocking I/O operations</td>\n<td>143</td>\n</tr>\n<tr>\n<td>B.1.2 Non-Blocking I/O Operations</td>\n<td>144</td>\n</tr>\n<tr>\n<td>B.1.3 SOLARIS use of SIGALRM</td>\n<td>144</td>\n</tr>\n<tr>\n<td>B.1.4 Polling I/O Operations</td>\n<td>145</td>\n</tr>\n<tr>\n<td>B.2 VxWorks Environment</td>\n<td>145</td>\n</tr>\n<tr>\n<td>B.2.1 Blocking I/O Operations</td>\n<td>146</td>\n</tr>\n<tr>\n<td>B.2.2 Non-Blocking I/O Operations</td>\n<td>146</td>\n</tr>\n<tr>\n<td>B.3 VMS Environment</td>\n<td>147</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>C TSI Logging and Tracing</td>\n<td>149</td>\n</tr>\n<tr>\n<td>C.1 TSI Logging</td>\n<td>149</td>\n</tr>\n<tr>\n<td>C.2 TSI Tracing</td>\n<td>150</td>\n</tr>\n<tr>\n<td>C.2.1 Trace Definitions</td>\n<td>150</td>\n</tr>\n<tr>\n<td>C.2.2 Decoded Trace Layout</td>\n<td>152</td>\n</tr>\n</tbody>\n</table>\nList of Figures\n\nFigure 1-1: Freeway Configuration ........................................... 19\nFigure 1-2: Embedded ICP Configuration ................................... 20\nFigure 1-3: A Typical Freeway Environment ............................. 23\nFigure 1-4: TSI Environment ................................................. 26\nFigure 1-5: TSI in the Freeway Operating Environment .................. 27\nFigure 2-2: Client TSI Configuration File Changes ...................... 34\nFigure 2-1: Client DLI Configuration File Changes (BSC Example) .... 34\nFigure 2-3: Server MuxCfg TSI Configuration File Changes ............ 35\nFigure 2-4: TSI Buffer Size Example .................................... 37\nFigure 2-5: DLI Buffer Size Example .................................... 38\nFigure 2-6: Comparison of malloc and tBufAlloc Buffers ............... 42\nFigure 2-7: Using the malloc Function for Buffer Allocation ............ 42\nFigure 3-1: TSI Architecture ................................................ 49\nFigure 3-2: Example Configuration for TCP/IP Socket Transport Interface .......... 61\nFigure 3-3: Example Configuration for Shared-Memory Transport Interface .......... 63\nFigure 3-4: TSI Configuration File (MuxCfg) for Protogate Server-Resident TSI .... 66\nFigure 4-1: TSI System Configuration Data Structure ..................... 76\nFigure 4-2: TSI Connection Status Data Structure ....................... 78\nFigure C-1: TSI Trace File Format ........................................ 158\nFigure C-2: TRACE_FCB ‘C’ Structure .................................... 158\nFigure C-3: TSI_TRACE_HDR ‘C’ Structure ................................ 159\nList of Tables\n\nTable 2-1: Required Values for Calculating New $\\text{MaxBufSize}$ Parameter .......................... 34\nTable 3-1: TSI Parameters for “main” Definition ................................................................. 54\nTable 3-2: TSI Parameters for Non-Transport Specific Connection ................................. 56\nTable 3-3: TSI Parameters for TCP/IP Socket Transport Connection ............................... 58\nTable 3-4: TSI Parameters for Shared-Memory Transport Connection .............................. 59\nTable 4-1: TSI Function Groups ......................................................................................... 72\nTable 4-2: TSI Functions: Syntax and Parameters (Listed in Typical Call Order) .............. 74\nTable 4-3: TSI System Configuration Data Structure Fields .............................................. 77\nTable 4-4: TSI Connection Status Data Structure Fields .................................................... 79\nTable A-1: TSI Command-specific Error Codes .................................................................. 137\nPreface\n\nPurpose of Document\n\nThis document describes Protogate's transport subsystem interface (TSI). The TSI helps you develop applications interfacing with a Freeway communications server or embedded intelligent communications processor (ICP).\n\nNote\n\nIn this document, the term “Freeway” can mean either a Freeway server or an embedded ICP. For the embedded ICP, also refer to the user guide for your ICP and operating system (for example, the ICP2432 User Guide for Windows NT).\n\nIntended Audience\n\nThis document should be read by application programmers. You should be familiar with the C programming language and have some knowledge of networks.\n\nIf your application will use Protogate's data link interface (DLI), which uses the TSI, you will need to use TSI only for configuration (see Chapter 3 of this document). Additionally, you should be familiar with the Freeway Data Link Interface Reference Guide.\n\nIf your application will interface directly to the TSI, you should be familiar with the programming details described in this document. If your TSI application will interface to one of Protogate's protocol services running on a Freeway ICP, you will also need to be\nfamiliar with the Freeway Client-Server Interface Control Document and your particular protocol programmer’s guide.\n\n**Organization of Document**\n\nChapter 1 is an overview of Freeway and the TSI.\n\nChapter 2 describes various TSI concepts that you should understand before writing an application program.\n\nChapter 3 describes the TSI configuration services.\n\nChapter 4 gives details of each TSI function.\n\nAppendix A lists additional error codes not included in the reference sections. It also provides summary tables of all TSI error codes as they relate to specific TSI function calls.\n\nAppendix B compares I/O handling in the UNIX, VMS, and VxWorks environments.\n\nAppendix C describes the TSI logging and tracing capabilities.\n\n**Protogate References**\n\nThe following general product documentation list is to familiarize you with the available Protogate Freeway and embedded ICP products. The applicable product-specific reference documents are mentioned throughout each document (also refer to the “readme” file shipped with each product). Most documents are available on-line at Protogate’s web site, www.protogate.com.\n\n**General Product Overviews**\n\n- Freeway 1100 Technical Overview 25-000-0419\n- Freeway 2000/4000/8800 Technical Overview 25-000-0374\n- ICP2432 Technical Overview 25-000-0420\n- ICP6000X Technical Overview 25-000-0522\nHardware Support\n\n- Freeway 1100/1150 Hardware Installation Guide\n DC-900-1370\n- Freeway 1200/1300 Hardware Installation Guide\n DC-900-1537\n- Freeway 2000/4000 Hardware Installation Guide\n DC-900-1331\n- Freeway 3100 Hardware Installation Guide\n DC-900-2002\n- Freeway 3200 Hardware Installation Guide\n DC-900-2003\n- Freeway 3400 Hardware Installation Guide\n DC-900-2004\n- Freeway 3600 Hardware Installation Guide\n DC-900-2005\n- Freeway 8800 Hardware Installation Guide\n DC-900-1553\n- Freeway ICP6000R/ICP6000X Hardware Description\n DC-900-1020\n- ICP6000(X)/ICP9000(X) Hardware Description and Theory of Operation\n DC-900-0408\n- ICP2424 Hardware Description and Theory of Operation\n DC-900-1328\n- ICP2432 Hardware Description and Theory of Operation\n DC-900-1501\n- ICP2432 Electrical Interfaces (Addendum to DC-900-1501)\n DC-900-1566\n- ICP2432 Hardware Installation Guide\n DC-900-1502\n\nFreeway Software Installation and Configuration Support\n\n- Freeway Message Switch User Guide\n DC-900-1588\n- Freeway Release Addendum: Client Platforms\n DC-900-1555\n- Freeway User Guide\n DC-900-1333\n- Freeway Loopback Test Procedures\n DC-900-1533\n\nEmbedded ICP Software Installation and Programming Support\n\n- ICP2432 User Guide for Digital UNIX\n DC-900-1513\n- ICP2432 User Guide for OpenVMS Alpha\n DC-900-1511\n- ICP2432 User Guide for OpenVMS Alpha (DLITE Interface)\n DC-900-1516\n- ICP2432 User Guide for Solaris STREAMS\n DC-900-1512\n- ICP2432 User Guide for Windows NT\n DC-900-1510\n- ICP2432 User Guide for Windows NT (DLITE Interface)\n DC-900-1514\n\nApplication Program Interface (API) Programming Support\n\n- Freeway Data Link Interface Reference Guide\n DC-900-1385\nDocument Conventions\n\nThis document follows the most significant byte first (MSB) and most significant word first (MSW) conventions for bit-numbering and byte-ordering. In all packet transfers\nbetween the client applications and the ICPs, the ordering of the byte stream is preserved.\n\nThe term “Freeway” refers to any of the Freeway server models (for example, Freeway 500/3100/3200/3400 PCI-bus servers, Freeway 1000 ISA-bus servers, or Freeway 2000/4000/8800 VME-bus servers). References to “Freeway” also may apply to an embedded ICP product using DLITE (for example, the embedded ICP2432 using DLITE on a Windows NT system).\n\nPhysical “ports” on the ICPs are logically referred to as “links.” However, since port and link numbers are usually identical (that is, port 0 is the same as link 0), this document uses the term “link.”\n\nProgram code samples are written in the “C” programming language.\n\nRevision History\n\nThe revision history of the Freeway Transport Subsystem Interface Reference Guide, Protogate document DC 900-1386D, is recorded below:\n\n<table>\n<thead>\n<tr>\n<th>Document Revision</th>\n<th>Release Date</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>DC 900-1386A</td>\n<td>February 1997</td>\n<td>Initial release using new document number: Include Release Notes for changes that potentially affect existing user applications.</td>\n</tr>\n<tr>\n<td>Special Freeway Server 2.5 Release</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>DC 900-1386B</td>\n<td>June 1998</td>\n<td>Incorporate previous release notes:</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Modify Buffer Management Section 2.3 on page 31</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Enhance error detection and reporting (Chapter 4 and Appendix A)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• Regarding “Error Handling for Dead Socket Detection,” refer to the Freeway Data Link Interface Reference Guide</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Dual Ethernet support is now handled by the “Added Interfaces” configuration described in the Freeway User Guide</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Simpact’s browser interface is no longer supported</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Modify Section 1.1 on page 17 for embedded ICPs</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Add IsSyncSelect function (Section 4.11 on page 114)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Add new error codes to Appendix A</td>\n</tr>\n<tr>\n<td>DC 900-1386C</td>\n<td>December 1999</td>\n<td>Add LocalPort TSI configuration parameter (Table 3–3 on page 58)</td>\n</tr>\n</tbody>\n</table>\nCustomer Support\n\nIf you are having trouble with any Protogate product, call us at (858) 451-0865 Monday through Friday between 8 a.m. and 5 p.m. Pacific time.\n\nYou can also fax your questions to us at (877) 473-0190 any time. Please include a cover sheet addressed to “Customer Service.”\n\nWe are always interested in suggestions for improving our products. You can use the report form in the back of this manual to send us your recommendations.\nThis document describes Protogate's transport subsystem interface (TSI) to the Freeway communications server. The TSI presents a consistent, high-level, common interface across multiple clients, operating systems, and transport services. The TSI provides connection-oriented data services to your client application with a subroutine library. This library provides functions that permit your application to access, configure, establish and terminate connections, and exchange data with a TSI peer application. Within the Freeway server, the TSI is used by Freeway's message multiplexor (MsgMux) to communicate with client applications.\n\n**Note**\n\nIn this document, the term “Freeway” can mean either a Freeway server or an embedded ICP. For the embedded ICP, also refer to the user guide for your ICP and operating system (for example, the Freeway User Guide).\n\n### 1.1 Product Overview\n\nProtogate provides a variety of wide-area network (WAN) connectivity solutions for real-time financial, defense, telecommunications, and process-control applications. Protogate's Freeway server offers flexibility and ease of programming using a variety of LAN-based server hardware platforms. Now a consistent and compatible embedded intelligent communications processor (ICP) product offers the same functionality as the Freeway server, allowing individual client computers to connect directly to the WAN.\nBoth Freeway and the embedded ICP use the same data link interface (DLI). Therefore, migration between the two environments simply requires linking your client application with the proper library. Various client operating systems are supported (for example, UNIX, VMS, and Windows NT).\n\nProtogate protocols that run on the ICPs are independent of the client operating system and the hardware platform (Freeway or embedded ICP).\n\n1.1.1 Freeway Server\n\nProtogate’s Freeway communications servers enable client applications on a local-area network (LAN) to access specialized WANs through the DLI. The Freeway server can be any of several models (for example, Freeway 1100/1150, Freeway 1200/1300, Freeway 2000/4000, or Freeway 8000/8800). The Freeway server is user programmable and communicates in real time. It provides multiple data links and a variety of network services to LAN-based clients. Figure 1-1 shows the Freeway configuration.\n\nTo maintain high data throughput, Freeway uses a multi-processor architecture to support the LAN and WAN services. The LAN interface is managed by a single-board computer, called the server processor. It uses the commercially available VxWorks operating system to provide a full-featured base for the LAN interface and layered services needed by Freeway.\n\nFreeway can be configured with multiple WAN interface processor boards, each of which is a Protogate ICP. Each ICP runs the communication protocol software using Protogate’s real-time operating system.\n\n1.1.2 Embedded ICP\n\nThe embedded ICP connects your client computer directly to the WAN (for example, using Protogate’s ICP2432 PCIbus board). The embedded ICP provides client applications with the same WAN connectivity as the Freeway server, using the same data link interface (via the DLITE embedded interface). The ICP runs the communication protocol software using Protogate’s real-time operating system. Figure 1-2 shows the embedded ICP configuration.\nFigure 1-1: Freeway Configuration\nFigure 1-2: Embedded ICP Configuration\nSummary of product features:\n\n- Provision of WAN connectivity either through a LAN-based Freeway server or directly using an embedded ICP\n- Elimination of difficult LAN and WAN programming and systems integration by providing a powerful and consistent data link interface\n- Variety of off-the-shelf communication protocols available from Protogate which are independent of the client operating system and hardware platform\n- Support for multiple WAN communication protocols simultaneously\n- Support for multiple ICPs (two, four, eight, or sixteen communication lines per ICP)\n- Wide selection of electrical interfaces including EIA-232, EIA-449, EIA-530, and V.35\n- Creation of customized server-resident and ICP-resident software, using Protogate's software development toolkits\n- Freeway server standard support for Ethernet and Fast Ethernet LANs running the transmission control protocol/internet protocol (TCP/IP)\n- Freeway server standard support for FDDI LANs running the transmission control protocol/ internet protocol (TCP/IP)\n- Freeway server management and performance monitoring with the simple network management protocol (SNMP), as well as interactive menus available through a local console, telnet, or rlogin\n1.2 Freeway Client-Server Environment Using TSI\n\nFreeway acts as a gateway that connects a client on a local-area network to a wide-area network. Through Freeway, a client application can exchange data with a remote data link application. Your client application must interact with the Freeway server and its resident ICPs before exchanging data with the remote data link application.\n\nOne of the major Freeway components is the message multiplexor (MsgMux) that manages the data traffic between the LAN and the WAN environments. The client application typically interacts with the Freeway MsgMux through a TCP/IP BSD-style socket interface (or a shared-memory interface if it is a server-resident application (SRA)). The ICPs interact with the MsgMux through the DMA and/or shared-memory interface of the industry-standard bus to exchange WAN data.\n\nFrom the client application’s point of view, the complexities are handled through a simple and consistent transport subsystem interface (TSI) which provides connection-oriented functions (tConnect, tWrite, tRead, and tDisconnect). If your application interfaces directly with the TSI, many of the overhead details (such as I/O, header, and protocol specifics) must be handled by your application. In this case, you must be familiar not only with this document, but also with the Freeway Client-Server Interface Control Document. If your TSI application will communicate with a remote data link application, you must also be familiar with the appropriate protocol programmer’s guide.\n\nFigure 1–3 shows a typical Freeway connected to a locally attached client by a TCP/IP network across an Ethernet LAN interface. Running a client TSI application in the Freeway client-server environment requires the basic steps described in Section 1.2.1 through Section 1.2.5.\n1.2.1 Establishing Freeway Internet Addresses\n\nFreeway must be addressable in order for a client application to communicate with it. In the Figure 1-3 example, the TCP/IP Freeway server name is freeway2, and its unique Internet address is 192.52.107.100. The client machine where the client application resides is client1, and its unique Internet address is 192.52.107.99. Refer to the Freeway User Guide to initially set up your Freeway and download the operating system, server, and protocol software to Freeway.\n\n1.2.2 Defining the TSI Configuration\n\nAfter establishing the addressing for your client machine and Freeway server, you must define the TSI connections between your client application and Freeway. To accomplish this, you first define the configuration parameters in a TSI ASCII configuration file, and then you run the tsicfg preprocessor program to create a binary configuration file (see Chapter 3). The tInit function uses the binary configuration file to initialize the TSI environment. If your application uses the DLI, refer to the Freeway Data Link Interface Reference Guide for DLI configuration.\n\nFigure 1-3: A Typical Freeway Environment\n1.2.3 Establishing a Freeway TSI Connection\n\nAfter the TSI configuration is properly defined, your client TSI application uses the `tConnect` function to establish a TSI connection with the Freeway MsgMux through the TCP/IP BSD-style socket interface.\n\n1.2.4 Exchanging Data through the Freeway Message Multiplexor\n\nAfter the TSI connection is established, the client application can then exchange data through the Freeway MsgMux using the `tRead` and `tWrite` functions. If your application needs to exchange data with a remote data link application through a Freeway ICP, you must handle the protocol-specific link configuration and other details pertaining to the ICP. In this case, refer to your particular protocol programmer’s guide.\n\n1.2.5 Closing a Freeway Session\n\nWhen your application finishes exchanging data, it calls the `tDisconnect` function to disconnect from the Freeway MsgMux.\n1.3 TSI Overview and Features\n\nThe TSI provides a transport-independent data transfer mechanism with a common interface across varying operating systems. The TSI shields data transfer applications from any dependencies on the underlying transport service (TCP/IP sockets, shared memory, and so on). In addition, TSI applications are easily ported, due to the consistent TSI interface across all supported operating systems.\n\nThe TSI consists of the TSI configuration preprocessor program, tsicfg, and a statically linked reference library containing a set of flexible and easy-to-use functions to establish, maintain, and terminate a connection with a TSI peer application.\n\nThe tsicfg preprocessor provides flexibility to the TSI application by allowing the runtime characteristics of the TSI to be modified without recompiling the application software. The TSI can be configured to use blocking or non-blocking I/O. Non-blocking I/O allows an application to service multiple TSI connections without blocking on any one connection. The tsicfg preprocessor program is described in Chapter 3.\n\nThe TSI operates within a client-server scheme, in which a TSI “server” application listens for incoming connection requests from TSI “client” applications. However, any TSI application can function as both a client and a server; that is, a TSI application can both listen for incoming connection requests and send connection requests to other TSI server applications. Figure 1–4 shows some possible applications within a TSI environment.\n\nAs shown in Figure 1–5, a TSI “server” application is used by Freeway’s MsgMux. Thus TSI “client” applications can communicate in a peer relationship with the Freeway TSI “server” application. Remote client applications can use the TSI’s TCP/IP socket interface, while server-resident applications (SRAs) can use the TSI’s shared-memory interface. Each TSI client application shown in Figure 1–5 is in a peer relationship with the Freeway TSI server application (that is, there is a TSI connection between each client TSI and the Freeway MsgMux).\nFigure 1-4: TSI Environment\nFigure 1-5: TSI in the Freeway Operating Environment\nThe major features of the TSI are summarized as follows:\n\n- Communicates with the Freeway server's message multiplexor (MsgMux)\n- Communicates with other TSI applications\n- Provides transport-service-dependent operations\n- Permits transport-service-independent applications\n- Supports multiple TSI connections to multiple servers\n- Supports blocking I/O\n- Supports non-blocking I/O with notification by I/O completion handler (IOCH) or polling\n- Provides advanced queuing techniques to minimize internal task switches under the VxWorks operating system\n- Provides efficient buffer management to avoid excess memory movement\n- Provides flexible text-based configuration services\n- Provides an off-line configuration preprocessor program (tsicfg) to increase syntax and semantic checking capability and to reduce real-time (on-line) processing of the configuration parameters\n- Provides configuration for all significant TSI service parameters\nChapter 2\n\nTSI Concepts\n\nNote\nIn this document, the term “Freeway” can mean either a Freeway server or an embedded ICP. For the embedded ICP, also refer to the user guide for your ICP and operating system (for example, the ICP2432 User Guide for Windows NT).\n\nThe following TSI concepts are described in this chapter:\n\n• configuration at various levels of the Freeway environment\n\n• blocking versus non-blocking I/O\n\n• buffer management\n\n• system resource requirements\n\n2.1 Configuration in the Freeway Environment\n\nThere are several types of configuration required for a client TSI application to run in the Freeway environment:\n\n• Freeway server configuration\n\n• transport subsystem interface (TSI) connection configuration\n\n• protocol-specific ICP link configuration (if applicable)\nThe Freeway server is normally configured only once, during the installation procedures described in the Freeway User Guide. TSI connection configuration is defined by specifying parameters in a TSI ASCII configuration file and then running the tsicfg preprocessor program to create a binary configuration file. Chapter 3 describes TSI configuration.\n\nIf your application communicates with one of Protogate’s data link protocols running on the ICP, you must be familiar with link configuration as described in your particular protocol programmer’s guide.\n\n### 2.2 Blocking versus Non-blocking I/O\n\n**Note**\n\nEarlier Freeway releases used the term “synchronous” for blocking I/O and “asynchronous” for non-blocking I/O. Some parameter names reflect the previous terminology.\n\nNon-blocking I/O applications are useful when doing I/O to multiple channels with a single process where it is not possible to “block” (sleep) on any one channel. Blocking I/O applications are useful when it is reasonable to have the calling process wait for I/O completion. For example, if you wish to design an application requiring the input of a keyboard as well as background processing, non-blocking I/O would be more efficient, because your process can perform other tasks while waiting for keyboard input.\n\nIn the Freeway environment, the term blocking I/O indicates that the open, close, connect, disconnect, read and write functions do not return until the I/O is complete. For non-blocking I/O, these functions might return after the I/O has been queued at the client, but before the transfer to Freeway is complete. The client must handle I/O completions at the software interrupt level in the completion handler established by the tInit or tConnect function, or by periodic use of tPoll to query the I/O completion status.\nThe effects on different TSI functions, resulting from the choice of blocking or non-blocking I/O, are explained in each function description in Chapter 4.\n\n### 2.2.1 I/O Completion Handler for Non-Blocking I/O\n\nWhen your application uses non-blocking I/O and an I/O condition occurs, the current task is preempted by a high-priority task called an I/O completion handler (IOCH) which is designated to handle the I/O. This high-priority IOCH is written by the application programmer and should adhere to the following real-time criteria to prevent the IOCH from impacting overall system performance:\n\n- minimize the amount of processing performed within the IOCH so other vital system operations are not prevented from executing\n- allow the non-preemptive priority routines to complete the processing\n- avoid activities such as disk I/O which might block the operations\n\n### 2.3 Buffer Management\n\nThis section describes how the Freeway buffer management system operates. For users who do not need a detailed understanding of the system design, Section 2.3.1 gives a system buffer overview and an example for reconfiguring your system buffers. Section 2.3.2 through Section 2.3.6 give the detailed information for those interested.\n\n---\n\n**Note**\n\nFreeway buffer management is implemented in the TSI; however DLI uses the TSI system for its own buffer management. Therefore, the DLI perspective is also presented throughout this section. If your application interfaces to the TSI only (not the DLI), you can disregard the DLI-specific information.\n\n---\n2.3.1 Overview of the Freeway System Buffer Relationships\n\nIn the Freeway environment, user-configurable buffers exist in the ICP, the client, and the server. These buffers must be coordinated for proper operation between the client application, the Freeway server, and the ICP. The default sizes for each of these buffers are designed for operation in a typical Freeway system. However, if your system requires reconfiguration of buffer sizes, the basic procedure is as follows (Section 2.3.1.1 gives an example calculation):\n\nStep 1: As a general rule, define the ICP buffer size first. ICP buffers must be large enough to contain the largest application data buffer transmitted or received. Most Protogate protocols on a Freeway ICP provide a data link interface (DLI) configuration parameter (such as msgBlkSize for BSC) through which the user can configure the ICP message buffer size. The typical default ICP buffer size for most Protogate protocols is 1024. Refer to your protocol-specific Programmer’s Guide to determine the parameter name and default.\n\nNote\n\nIf your application does not interface to the DLI, the protocol-specific ICP buffer size is also software configurable. Refer to your protocol-specific Programmer’s Guide.\n\nStep 2: Define the client buffers in the client’s TSI configuration file. The TSI buffer pool is defined in the configuration file’s “main” section. An optional connection-specific maximum buffer size is allowed in each connection definition. These two configurations are detailed in Section 2.3.2.1 and Section 2.3.2.2, respectively. The buffer size specified in the associated connection definition must be large enough to contain the ICP buffer size.\nStep 3: Define the server buffers in the `MuxCfg` server TSI configuration file, which is located in your boot directory. This file is similar to the client TSI configuration file. As with the client, define the TSI buffer pool size in the `MuxCfg` file's \"main\" section. Then define the optional connection-specific maximum buffer size for each connection. Simply define the connection buffer size for the largest associated client requirement. The buffer pool size must be at least as large as the largest connection buffer size. Section 3.5 on page 65 discusses the `MuxCfg` file in detail, and Figure 3-4 on page 66 shows a `MuxCfg` file.\n\n### 2.3.1.1 Example Calculation to Change ICP, Client, and Server Buffer Sizes\n\nStep 1: Determine the maximum bytes of data your application must be able to transfer. For this example calculation, we are assuming a maximum of 1500 bytes to be transferred using the BSC protocol and interfacing to Protogate's DLI. This is the value that must be assigned to the ICP buffer size (the DLI `msgBlkSize` parameter for BSC).\n\nStep 2: Based on the above 1500-byte `msgBlkSize` parameter, calculate a new `MaxBufSize` for the ICP, client and server. Table 2-1 summarizes the values used in this example.\n\n\\[\n\\text{MaxBufSize} = \\text{msgBlkSize} + \\text{DLI header size}\n\\]\n\\[\n\\text{MaxBufSize} = 1500 \\text{ bytes} + 96 \\text{ bytes} = 1596 \\text{ bytes}\n\\]\n\nStep 3: Make the required changes to the protocol-specific portion of the client DLI configuration file as shown in Figure 2-1.\nStep 4: Make the required changes to the client TSI configuration file as shown in Figure 2–2.\n\n```\nmain // TSI “main” section: //\n{\n MaxBufSize = 1596; // Must be 1596 (or greater) //\n ...\n}\nConn1 // Connection-specific parameters //\n{\n MaxBufSize = 1596;\n ...\n}\n```\n\n**Figure 2–2:** Client TSI Configuration File Changes\nStep 5: Make the required changes to the server MuxCfg TSI configuration file (located in your boot directory) as shown in Figure 2-3.\n\n```\nmain // MuxCfg “main” section: //\n{\n MaxBufSize = 1596; // Must be 1596 (or greater) //\n ...\n}\nMuxConn1 // Connection-specific parameters //\n{\n MaxBufSize = 1596;\n ...\n}\n```\n\n**Figure 2-3: Server MuxCfg TSI Configuration File Changes**\n\n### 2.3.2 Client TSI Buffer Configuration\n\nFor users who need to understand the details of the buffer management system, review Section 2.3.2 through Section 2.3.6 carefully. After you define the ICP buffer size as described in Step 1 on page 32, the next step is to define the client TSI buffers.\n\nThe TSI provides its own buffer management scheme. Definitions in the client TSI configuration file allow you to create fixed-sized buffers in a TSI-controlled buffer pool (see Section 2.3.2.1). Each connection can then optionally be assigned a unique maximum buffer size (see Section 2.3.2.2). TSI applications can then access these buffers using the tBufAlloc and tBufFree TSI functions.\n\n---\n\n**Note**\n\nFor applications using Protogate’s data link interface, the DLI uses the TSI buffer management system for its own buffer management. The dlBufAlloc and dlBufFree DLI functions provide access to buffers in the TSI buffer pool.\nYour application is not required to use the TSI buffer management facilities, but Proto-\ngate highly recommends it for the following reasons:\n\n- TSI allocates all buffers up front, resulting in better real-time performance than\n allocation through C \\texttt{malloc} and \\texttt{free} functions\n- The number of TSI buffers is configurable for operating environments with lim-\n ited system resources\n- TSI allocates the buffer pool on boundaries which minimize memory access over-\n head\n- TSI overhead is invisible to the user\n\n2.3.2.1 TSI Buffer Pool Definition\n\nThe TSI buffer pool is configured through two parameter definitions in the “main” sec-\n\ntion of the client TSI configuration file (Section 3.3.1 on page 54). The \\texttt{MaxBufSize}\n\nparameter specifies the maximum size of each buffer in the TSI buffer pool. The \\texttt{MaxBuffers}\n\nparameter specifies the maximum number of buffers available in the TSI\n\nbuffer pool and must support the maximum number of I/O requests that could be out-\n\nstanding at any one time. After adjusting \\texttt{MaxBufSize} as described below, the product of\n\nthe \\texttt{MaxBufSize} and \\texttt{MaxBuffers} parameters defines the TSI buffer pool size.\n\n\\texttt{MaxBufSize} defines the maximum size of each buffer. This is the actual data size\n\nthe TSI user application has available for its own use. When the buffer pool is defined, TSI cal-\n\nculates an “effective” buffer size which is \\texttt{MaxBufSize} plus the additional bytes re\nquired\n\nfor a TSI header plus any alignment bytes. Alignment bytes are required only if the value\n\nof \\texttt{MaxBufSize} plus the TSI header bytes is not divisible by 4.\n\nThis “effective” buffer size is invisible to the user application (regardless of whether it\n\ninterfaces to the DLI or the TSI); all interactions with the TSI buffer management facili-\nties are based on \\texttt{MaxBufSize} and the connection-specific parameter described in\n\nSection 2.3.2.2. If you define \\texttt{MaxBufSize} as 1000 bytes, TSI assures that the buffer pool\n\ncan provide 1000 bytes for TSI application data.\nFigure 2–4 illustrates an example buffer calculation assuming the following sizes:\n\n- MaxBufSize is 1000 bytes\n- The TSI header is 18 bytes\n- The necessary alignment to make the total divisible by 4 is 2 bytes\n\nTSI adds 18 bytes to the MaxBufSize value to include the TSI header, making the actual size of the buffer allocated by TSI 1018 bytes. Because this actual size is not divisible by 4, TSI increments the value to the next modulo-4 value, in this case, 1020. Regardless of the final size, your TSI application has control of only MaxBufSize bytes.\n\nThe TSI application program can obtain the value of MaxBufSize using a tPoll request for the system configuration. Refer to the TSI_POLL_GET_SYS_CFG option (described on page 101 and in Section 4.1.3.1 on page 76), which returns the iMaxBufSize field (described on page 77).\n\n\nNote\n\nThe Figure 2–4 example, as viewed from the DLI application’s perspective is shown in Figure 2–5. Of the 1000 bytes specified by the TSI MaxBufSize parameter, 76 bytes are required for the DLI header. After calling dlOpen, the DLI application program can call dlPoll with the DLI_POLL_GET_SESS_STATUS option, which returns the usMaxSessBufSize field. This value is the actual data size available to the DLI application (924 bytes in the Figure 2–5 example).\n\nFigure 2–5: DLI Buffer Size Example\n\n2.3.2.2 Connection-Specific Buffer Definition\n\nAfter the TSI buffer pool is defined, you have the option of defining a unique maximum buffer size for each connection in the client TSI configuration file. If undefined, the connection buffer size defaults to the MaxBufSize “main” definition for the TSI buffer pool described in the previous Section 2.3.2.1.\nNote\n\nThe maximum connection buffer size should be at least as large as the defined ICP buffer size, plus any additional client requirements. For example, if you are using the DLI, you must include DLI overhead bytes in the total size of the application data area (see Figure 2–5).\n\nTo define a unique buffer size for a connection, use the connection-specific MaxBufSize parameter described in Section 3.3.2 on page 56. This connection buffer size is the buffer size the system allows the user for tWrite requests. No connection buffer size can be larger than MaxBufSize defined for the TSI buffer pool.\n\nThe connection buffer size does not change the actual size of the buffer (actual buffers are all MaxBufSize as defined for the TSI buffer pool); it only limits the acceptable size of application write buffers given to TSI through a tWrite request. It enforces a maximum data size that can be sent to the server in any one tWrite request. The tWrite function returns a TSI_WRIT_ERR_INVALID_LENGTH error if the write is attempted with a buffer exceeding the connection's maximum buffer size.\n\nThe tRead requests are not limited by the connection buffer size. The size of read requests, when using tRead, is defined by MaxBufSize for the TSI buffer pool (in the “main” definition of the TSI configuration file).\n\n2.3.2.3 TSI Buffer Size Negotiation\n\nA connection’s maximum buffer size can be changed “silently.” When the client’s connection to the Freeway server is accomplished, the client TSI and the server TSI negotiate a maximum buffer size for the established connection. If the sizes are different, the side with the larger connection buffer size changes its size to that of the smaller. After the connection is established, the negotiated maximum buffer size is available using a tPoll request for connection status. Refer to the TSI_POLL_GET_CONN_STATUS option (described on page 101 and in Section 4.1.3.2 on page 78), which returns the\nusMaxConnBufSize field (described on page 79). Note that this “final” size is not available until the connection has been successfully established.\n\n---\n\n**Note**\n\nThe DLI application program can obtain the actual data size (after the TSI negotiation process during dlOpen) using a dlPoll request with the DLI POLL GET SESS STATUS option, which returns the usMaxSessBufSize field. Refer to the example provided in the Freeway Data Link Interface Reference Guide. A similar approach would apply to using the TSI usMaxConnBufSize field obtained by calling tPoll with the TSI POLL GET CONN STATUS option.\n\n---\n\n### 2.3.3 Server TSI Buffer Configuration\n\nAfter defining the ICP buffers and the client TSI buffers, the final step is to define the server TSI buffers. The same TSI buffer management design details apply to the server TSI buffers that were described in Section 2.3.2 on page 35 for the client TSI buffers. The only difference is that the server buffer definitions are specified in the MuxCfg server TSI configuration file, which is located in your boot directory. As with the client, define the TSI buffer pool size in the MuxCfg file’s “main” section. Then define the optional connection-specific maximum buffer size for each connection. Simply define the connection buffer size for the largest associated client requirement. The buffer pool size must be at least as large as the largest connection buffer size. Section 3.5 on page 65 discusses the MuxCfg file in detail, and Figure 3–4 on page 66 shows a MuxCfg file. Refer back to Section 2.3.1.1 on page 33 for a sample calculation of ICP, client, and server buffer sizes.\n\n### 2.3.4 Buffer Allocation and Release\n\nThe TSI application obtains a buffer from the TSI buffer pool using the tBufAlloc function. The returned buffer address points to the available data area as shown in Figure 2–4 on page 37. The size returned is always the MaxBufSize defined for the buffer.\npool (Table 3-1 on page 54). While the entire data area is available for user data, note the restrictions discussed previously in Section 2.3.2.2 regarding limits placed on tWrite requests by the connection's maximum buffer size definition. The user application releases a buffer back to the TSI buffer pool using the tBufFree function.\n\nNote\n\nDLI applications use the dlBufAlloc and dlBufFree functions to access buffers in the TSI buffer pool.\n\n2.3.5 Cautions for Changing Buffer Sizes\n\nIf you need to change the buffer size of your application, keep the following cautions in mind:\n\n- If you increase the ICP buffer size, there may be corresponding changes required in the client and server buffer sizes.\n\n- If you have limited resources and increase the client or server MaxBufSize parameter, consider decreasing the number of buffers allocated in the buffer pool (the MaxBuffers parameter in the client TSI configuration file and the server MuxCfg file).\n\n- Client read buffers too small for an inbound data buffer are returned to the client application with a TSI_READ_ERR_OVERFLOW error indication. Write requests with buffers too large are returned with a TSI_WRIT_ERR_INVALID_LENGTH error indication.\n\n2.3.6 Using Your Own Buffers\n\nIf your TSI application needs to use its own buffers, it must know the exact number of overhead bytes used to store the TSI header information. Your application should call tPoll to get the TSI system configuration information (Section 4.8 on page 100) so that it can allocate buffers correctly. Each buffer must be at least iMaxBufSize + usOverhead\nbytes in size (these values are described on page 77). Your application must give TSI the address of the memory buffer that is at usOverhead bytes from the beginning of the data area. Figure 2–6 shows a comparison of using the “C” malloc function versus the TSI tBufAlloc function for buffer allocation. Figure 2–7 is a “C” code fragment demonstrating the use of the malloc function.\n\n**Note**\nFor information about using your own buffers in a DLI application, see the Freeway Data Link Interface Reference Guide.\n\n---\n\n**Figure 2–6**: Comparison of malloc and tBufAlloc Buffers\n\n---\n\n```\n... PCHAR pBuf;\nTSI_SYS_CFG sysCfg;\nint iBufSize, iConnID;\n...\n\ntpoll (0, TSI_POLL_GET_SYS_CFG, (PCHAR*)NULL, (PINT)NULL, (PCHAR)&sysCfg);\niBufSize = (int) sysCfg.usOverhead + sysCfg.iMaxBufSize;\npBuf = (PCHAR) malloc (iBufSize);\n...\n\nfwrite (iConnID, &pBuf(sysCfg.usOverhead), 100, TSI_WRITE_NORMAL);\n...```\n\n---\n\n**Figure 2–7**: Using the malloc Function for Buffer Allocation\n2.3.7 Buffer Management (Client versus Server-Resident Applications)\n\nWriting a server-resident application (SRA) using the TSI interface is much like writing a client application. The usual sequence of steps in a client application is:\n\n1. Call `tBufAlloc` (Section 4.2 on page 80) to obtain a buffer.\n2. Load the buffer with data.\n3. Call `tWrite` (Section 4.13 on page 120), which copies the data for further processing.\n4. Call `tBufFree` (Section 4.3 on page 82) to release the buffer allocated in Step 1.\n5. Call `tRead` (Section 4.10 on page 109), supplying a NULL pointer for the buffer address so that the TSI allocates the buffer for the client application.\n6. Call `tBufFree` (Section 4.3 on page 82) to release the buffer allocated by the TSI in Step 5.\n\nHowever, there is one significant difference in the way buffers are managed for an SRA which uses the TSI interface (refer back to Figure 1-3 on page 23 to see how an SRA fits in a typical Freeway environment). When the TSI code at the SRA interacts with the TSI code at the MsgMux, the address of the buffer is passed instead of copying the contents of the buffer. At this point, the write is complete for the SRA; however, the buffer is still in use. Eventually the MsgMux writes the buffer to the ICP through the ICP driver. When the driver completes the write, the MsgMux releases the buffer. Therefore, even though the SRA allocated the buffer, it must not release it.\n\nTherefore, Step 4 above is eliminated, and the modified sequence of steps for an SRA is shown below. Refer to the Freeway Server-Resident Application and Server Toolkit Programmer Guide for more information on SRAs.\n1. Call \\texttt{tBufAlloc} (Section 4.2 on page 80) to obtain a buffer.\n\n2. Load the buffer with data.\n\n3. Call \\texttt{tWrite} (Section 4.13 on page 120), which passes the address of the buffer. Eventually the \\texttt{MsgMux} writes the buffer to the ICP through the ICP driver. When the driver completes the write, the \\texttt{MsgMux} releases the buffer.\n\n4. Call \\texttt{tRead} (Section 4.10 on page 109), supplying a NULL pointer for the buffer address so that the DLI allocates the buffer for the SRA.\n\n5. Call \\texttt{tBufFree} (Section 4.3 on page 82) to release the buffer allocated by the TSI in Step 5.\n\n### 2.4 System Resource Requirements\n\nWhen designing your TSI application, you must consider TSI resource requirements. They can be calculated as follows:\n\nTotal memory requirements = program size \\\\\n+ (number of buffers \\times size of buffer) \\\\\n+ (number of connections \\times 300) \\\\\n+ (number of connections \\times size of I/O queues \\times 44) \\\\\n+ 32,000\n\nWhere:\n\n- “number of buffers” is defined by the TSI \\texttt{MaxBuffers} parameter (page 54)\n- “size of buffer” is defined by the TSI \\texttt{MaxBufSize} parameter (page 55)\n- “number of connections” is defined by the TSI \\texttt{MaxConns} parameter (page 55)\n- “size of I/O queues” is defined by the sum of the TSI \\texttt{MaxInQ} parameter (page 56) and the TSI \\texttt{MaxOutQ} parameter (page 56)\n2.4.1 Signal Processing\n\nThe TSI disables all signals during processing. The signals are ultimately delivered when they are re-enabled at the end of the TSI call. If this constraint causes a problem for your client application, consider implementing one of the following:\n\n- use non-blocking I/O as described in Section 2.2 on page 30\n- use the Timeout TSI configuration parameter (page 57)\n\nUnder VMS, ASTs are disabled instead of signals.\nFreeway Transport Subsystem Interface Reference Guide\n3.1 Configuration Process Overview\n\nThe transport subsystem interface (TSI) consists of two major components:\n\n- The `tsicfg` configuration preprocessor program defines the TSI environment prior to run time, using a text configuration file that you create or modify.\n- The TSI reference library is used to build your TSI application.\n\nThe advantage of using the `tsicfg` preprocessor program is that you do not have to rebuild your application when you redefine the TSI environment.\n\nThe TSI configuration process is a part of the installation procedure and the loopback testing procedure described in the Freeway User Guide. However, during your client application development and testing, you might need to perform TSI configuration repeatedly.\n\nThe TSI configuration process is summarized as follows:\n1. Create or modify a text file specifying the configuration of the transport subsystem interface (TSI) connections.\n\n2. Execute the `tsicfg` preprocessor program with the text file from Step 1 as input. This creates the TSI binary configuration file. If the optional TSI binary configuration filename is supplied, the binary file is given that name plus the `.bin` extension. If the optional filename is not supplied, the binary file is given the same name as your TSI text configuration file plus the `.bin` extension.\n\n `tsicfg TSI-text-configuration-filename [TSI-binary-configuration-filename]`\n\n**Note**\n\nYou must rerun `tsicfg` whenever you modify the text configuration file so that the TSI functions can apply the changes.\n\nWhen your application calls the `tInit` function, the TSI binary configuration file is used to configure the TSI connections. Figure 3-1 shows the TSI architecture.\n\n**Note**\n\nThe Freeway User Guide describes the make files and command files provided to automate the above process and copy the resulting binary configuration files to the appropriate directories. Additionally, each protocol programmer’s guide describes the related protocol specifics of the TSI configuration process.\nFigure 3-1: TSI Architecture\n3.2 Introduction to TSI Configuration\n\nThe tsicfg configuration preprocessor program translates a TSI text configuration file into a binary configuration file. During the translation process, tsicfg processes and verifies each configuration entry in the text configuration file, and the results are stored in the binary configuration file. This process ensures the validity of the configuration parameters before their use by the TSI reference library. The TSI configuration services provide the following features:\n\n- Free-formatted configuration language\n- Informative parameter names\n- Procedure-like definition entry for each connection definition\n- Extensive syntax checking capability\n- Extensive semantic checking capability\n- Connection-based definition capability\n\nThe TSI reference library is a set of function calls used by applications to exchange data between two or more applications over a well-defined transport interface (for example, TCP/IP, shared-memory, APPC/LU 6.2, and so on). The TSI reference library uses the TSI binary configuration file to configure the TSI services as well as connections managed by the TSI. Together with the TSI configuration services, the TSI reference library provides a simple network programming environment for transport-independent applications. It also provides end users the ability to configure individual TSI connections according to their needs.\n\n3.2.1 TSI Configuration Language\n\nThe TSI text configuration file contains an optional “main” definition followed by one or more unique connection definitions. The “main” definition specifies general TSI characteristics and must use the name “main.” Each connection definition entry in the TSI text configuration file defines a specific type of TSI connection to be established\nbetween the TSI application and a peer TSI application. Refer to Section 3.6.2 for details of the language grammar. The TSI configuration is described as follows:\n\n```\nmain\n{\n parameter-name = parameter-value; // comments are ignored //\n}\n\nconnection-name\n{\n parameter-name = parameter-value;\n}\n```\n\nEach definition entry must be assigned a name that is unique within the configuration file; tsicfg makes no attempt to ensure the uniqueness of names within the same configuration file. Each `connection-name` uniquely identifies a connection within the same configuration file; it is supplied by the user. Each `parameter-name` is uniquely defined by `tsicfg`; the `parameter-value` is supplied by the user. Comments are considered white spaces and are ignored by `tsicfg`.\n\n### 3.2.2 Rules of the TSI Configuration File\n\nA connection or a parameter name must adhere to the following naming rules:\n\n1. It is similar to variable names in the C language.\n2. It can be a string of alphabetic (A through Z, a through z, and _) and numeric (0 through 9) characters.\n3. The first character must be alphabetic.\n4. The length must not be more than 20 characters.\n5. Connection names are case-sensitive while parameter names are not.\n6. The TSI does not verify the duplication of connection definition entries at the connection level or at the parameter level. That means if you have defined the same connection entry more than once, the first one is used. If you have defined a parameter within a connection definition entry more than once, the last value is used.\n3.2.3 Binary Configuration File Management\n\nThe binary configuration file is created in the same directory as the location of the text configuration file (unless a different path is supplied with the optional filename described in Section 3.1 on page 47). On all but VMS systems, if a file already exists in that directory with the same name, the existing file is renamed by appending the .BAK extension. If the renamed file duplicates an existing file in the directory, that existing file is removed by the configuration preprocessor program.\n\nNote\n\nThe default binary configuration name contains the period `.` character which plays a special role in the processing of the configuration files. See Section 3.2.4.\n\n3.2.4 On-line Configuration File Processing\n\nTSI can perform the configuration processing on-line. While this feature is available, Protogate recommends adherence to the off-line configuration file process previously described in Section 3.1 on page 47, which is better managed and slightly more efficient.\n\nThe off-line process can be performed on-line during TSI initialization (tini) by providing a configuration filename without an embedded `.` character. When such a filename is recognized, TSI attempts to open the file as a text file and calls the TSI configuration preprocessor program (tsicfg). The output file is named “filename”.bin. An error in the configuration file aborts the tini processing with an appropriate error in the TSI log file.\n\nThis on-line method requires the configuration text file and the tsicfg preprocessor program to reside in the same directory as the application executable. The resulting .bin file is placed in this same directory.\n3: TSI Configuration\n\nNote\n\nUnless on-line configuration is desired, be sure a ‘.’ character appears in the configuration filename provided to `tInit`.\n\n3.3 TSI Connection Definition\n\nThere are two groups of TSI configuration parameters: the “main” definition and the connection definitions. Some of the parameters are found in both sets; in this case, the parameter value in the “main” definition applies to the TSI application in general, while the value in a specific connection definition applies only to those TSI connections using that connection definition (unique connection-name). The connection definition parameters allow the application to use connections with different operating characteristics at the same time. For example, a client TSI application using the TCP/IP socket interface can connect to multiple TSI server applications on various remote host machines. For each host machine, the client specifies a connection definition in its TSI configuration file with the `server` parameter set to the IP (Internet Protocol) address of the remote host. In addition, if the configuration needs of the application change (for example, the IP address of a remote host changes), only the configuration file needs to be modified; the application does not need to be modified or re-compiled.\n\nThe configuration parameters can be one of three types of values: integer, boolean, or character string. Integer values can be specified as ANSI C decimal, octal, or hexadecimal constants. Boolean and string values are specified as ANSI C character strings (enclosed in double quotes). Boolean values must consist of a string containing the word “yes” or the word “no.” The TSI configuration preprocessor ignores the case of boolean values; that is, “Yes” and “YES” are also valid boolean values. In addition, `tsicfg` ignores the case of parameter names. The parameter definitions in the following sections are given in upper and lower case for readability only. TSI uses a default value for any parameters not explicitly defined.\n3.3.1 Parameters for the “main” Definition\n\nThe first section in the TSI text configuration file, which is called “main,” specifies the TSI configuration for non-connection-specific operations. If a “main” definition is not specified in the TSI text configuration file, a default “main” entry is used.\n\nThe “main” TSI parameters are shown alphabetically in Table 3-1, along with the defaults. You need to include only those parameters whose values differ from the defaults.\n\n### Table 3-1: TSI Parameters for “main” Definition\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Default</th>\n<th>Valid Values</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AsyncIO</td>\n<td>“no”(^a)</td>\n<td>boolean</td>\n<td>Boolean value specifying the use of blocking or non-blocking I/O. A value of “no” specifies blocking I/O.</td>\n</tr>\n<tr>\n<td>DualAddress</td>\n<td>n/a</td>\n<td>n/a</td>\n<td>This parameter is replaced by the “Added Interfaces” configuration described in the Freeway User Guide.</td>\n</tr>\n<tr>\n<td>InterruptTrace</td>\n<td>“no”</td>\n<td>boolean</td>\n<td>A boolean value specifying whether interrupts should be locked out during tracing.</td>\n</tr>\n<tr>\n<td>LogLev</td>\n<td>0</td>\n<td>0–7</td>\n<td>An integer value defining the level of logging the TSI performs and stores in the file name defined by the LogName parameter. A higher level specifies more detailed logging; 0 specifies no logging.</td>\n</tr>\n<tr>\n<td>LogName</td>\n<td>“tsilog”</td>\n<td>string (6–80)</td>\n<td>A string of characters defining the name (path) of the file for storing the TSI logging information. If the path is not included, the current directory is assumed.</td>\n</tr>\n<tr>\n<td>MaxBuffers</td>\n<td>1024</td>\n<td>4–4096</td>\n<td>An integer value specifying the maximum number of buffers to be allocated during run time for the TSI buffer pool. To prevent your application running out of buffers, take care when you specify MaxBuffers to consider the number of TSI connections you need and the queue sizes (MaxInQ and MaxOutQ on page 56). See Section 2.3 on page 31 for details on buffer management.</td>\n</tr>\n</tbody>\n</table>\n\n\\(^a\\)For Protogate’s Freeway server TSI, AsyncIO must be set to “yes” (refer to Section 3.5 on page 65)\n### Table 3-1: TSI Parameters for “main” Definition (Cont’d)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Default</th>\n<th>Valid Values</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>MaxBufSize</td>\n<td>1024 + TSI overhead</td>\n<td>1–64000</td>\n<td>An integer value specifying the maximum size of each buffer in the TSI buffer pool. This user-supplied value does not include TSI overhead; the TSI overhead value is calculated by TSI and supplied to the user via the <code>usOverhead</code> parameter (page 77). See Section 2.3 on page 31 for details on buffer management.</td>\n</tr>\n<tr>\n<td>MaxConns</td>\n<td>1024</td>\n<td>1–1024</td>\n<td>An integer value defining the maximum number of connections the TSI can manage at one time.</td>\n</tr>\n<tr>\n<td>ServerName</td>\n<td>“Freeway”</td>\n<td>string</td>\n<td>A string of characters specifying the name of a TSI “server” application that runs in the VxWorks environment. This parameter applies only to TSI “server” applications using the shared-memory interface; the purpose is to identify themselves to server-resident applications (SRAs) operating as shared-memory clients. The <code>Server</code> parameter in a shared-memory “client” connection’s configuration definition must match the <code>ServerName</code> parameter in the “server’s” configuration definition. Also see the <code>Server</code> parameter (page 57)</td>\n</tr>\n<tr>\n<td>StackSize</td>\n<td>10240</td>\n<td>1–64000</td>\n<td>An integer value specifying the value of the stack to be used by the TSI for spawning its internal tasks. This parameter applies only to the VxWorks environment.</td>\n</tr>\n<tr>\n<td>TraceLev</td>\n<td>0</td>\n<td>0–31</td>\n<td>An integer value defining the level of tracing (or the sum of several levels) which the TSI performs for this session. This parameter can be overridden by the connection definitions following the “main” section. See also Appendix C.</td>\n</tr>\n<tr>\n<td>TraceName</td>\n<td>“tsitrace”</td>\n<td>string</td>\n<td>A string of characters defining the name (path) of the file for storing the TSI tracing information. If the path is not included, the current directory is assumed.</td>\n</tr>\n<tr>\n<td>TraceSize</td>\n<td>0</td>\n<td>512–1048576</td>\n<td>An integer value specifying the size of the internal trace buffer. The default is zero (tracing is not performed). The smallest allowable size is 512.</td>\n</tr>\n</tbody>\n</table>\n### 3.3.2 Parameters for the Connection Definition (Non-transport Specific)\n\nEach additional connection definition specifies unique TSI connections; that is, each definition has a unique connection-name. The TSI parameters are shown alphabetically in Table 3–2, along with the defaults. You need to include only those parameters whose values differ from the defaults.\n\n**Table 3-2: TSI Parameters for Non-Transport Specific Connection**\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Default</th>\n<th>Values</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AsyncIO</td>\n<td>“no” a</td>\n<td>boolean</td>\n<td>Boolean value specifying the use of blocking or non-blocking I/O. A value of “no” specifies blocking I/O.</td>\n</tr>\n<tr>\n<td>LogLev</td>\n<td>0</td>\n<td>0–7</td>\n<td>An integer value defining the level of logging the TSI performs for this connection. A higher level specifies more detailed logging, while 0 specifies no logging. This value overrides the LogLev defined in the “main” section.</td>\n</tr>\n<tr>\n<td>MaxBufSize</td>\n<td>MaxBufSize defined in “main”</td>\n<td>1 to MaxBufSize defined in “main”</td>\n<td>An integer value specifying the maximum data size of the TSI buffers for this connection only. The value must be less than or equal to the “main” entry. The default value is the size specified in the “main” section.</td>\n</tr>\n<tr>\n<td>MaxErrors</td>\n<td>10</td>\n<td>10–100</td>\n<td>An integer value specifying the number of I/O errors the TSI can tolerate before declaring the connection is unusable.</td>\n</tr>\n<tr>\n<td>MaxInQ</td>\n<td>10</td>\n<td>2–1000</td>\n<td>An integer value specifying the number of entries in the TSI internal input queue. Make sure MaxBuffers defined in the “main” section (page 54) is adequate for your requirements, especially if your application uses non-blocking I/O. Use caution when changing the queue size parameters. TSI allocates buffers for each connection based on this parameter, and increasing the queue size could cause a buffer allocation problem on the server.</td>\n</tr>\n<tr>\n<td>MaxOutQ</td>\n<td>10</td>\n<td>2–1000</td>\n<td>An integer value specifying the number of entries in the TSI internal output queue. See MaxInQ above.</td>\n</tr>\n</tbody>\n</table>\n\n*a For Protogate's Freeway server TSI, AsyncIO must be set to \"yes\" (refer to the Freeway User Guide)*\nTable 3-2: TSI Parameters for Non-Transport Specific Connection (Cont’d)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Default</th>\n<th>Values</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Server</td>\n<td>none</td>\n<td>string</td>\n<td>A string of characters identifying the TSI “server” application with which to connect. This parameter is used differently for each transport interface:</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>(δ 20)</td>\n<td>• For “tcp-socket” connections, this parameter specifies the host machine on which the TSI “server” resides. The string can be either the machine’s host name or its IP address in “dot” notation (for example, “freeway2” or “192.52.107.100”). This parameter is used in conjunction with the WellKnownPort parameter (page 58) to establish “tcp-socket” connections. Note that your application may be blocked while TSI searches for the server’s name if your network has Domain Name Server (DNS) setup.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>• For “shared-memory” connections, this parameter identifies the TSI peer “server” application or process. The client connection’s Server parameter must match the server application’s ServerName parameter (page 55) defined in the “main” entry of the server application’s configuration file. The Server parameter is used in conjunction with the ShmPeerName parameter (page 59) to establish “shared-memory” connections.</td>\n</tr>\n<tr>\n<td>Timeout</td>\n<td>60</td>\n<td>0–63999</td>\n<td>An integer value specifying the number of seconds the TSI uses to time activities within this connection.</td>\n</tr>\n<tr>\n<td>TraceLev</td>\n<td>0</td>\n<td>0–31</td>\n<td>An integer value defining the level of tracing (or the sum of several levels) which the DLI performs for this session. If specified, this value overrides the “main” TraceLev parameter. See also Appendix C.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>0 = no trace 1 = read only 2 = write only 4 = interrupt only 8 = application IOCH 16 = user’s data</td>\n</tr>\n<tr>\n<td>Transport</td>\n<td>no default</td>\n<td>string</td>\n<td>A string of characters specifying the transport interface to be used by this connection. There are no defaults. Supported transport interfaces include “tcp-socket” for TCP/IP sockets and “shared-memory” for VxWorks shared-memory (server-resident applications).</td>\n</tr>\n<tr>\n<td></td>\n<td>(must be specified)</td>\n<td>(δ 20)</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nDC 900-1386D 57\n3.3.3 Parameters for Connection Definition (TCP/IP Socket Transport)\n\nThe TSI configuration parameters required for a TCP/IP socket transport connection are shown alphabetically in Table 3–3, along with the defaults. You need to include only those parameters whose values differ from the defaults. See Section 3.4.1 for an example.\n\n**Table 3-3: TSI Parameters for TCP/IP Socket Transport Connection**\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Default</th>\n<th>Valid Values</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>TCPKeepAlive</td>\n<td>“no”</td>\n<td>Boolean</td>\n<td>A Boolean value specifying whether or not TCP/IP should enable periodic transmission to keep a connected link active while there are no user data transmissions on the link.</td>\n</tr>\n<tr>\n<td>TCPNoDelay</td>\n<td>“no”</td>\n<td>Boolean</td>\n<td>A Boolean value specifying whether or not TCP/IP should send a small packet as soon as possible.</td>\n</tr>\n<tr>\n<td>WellKnownPort</td>\n<td>0x2010</td>\n<td>5001, 32676</td>\n<td>An integer value (usually specified in hexadecimal) specifying the TCP/IP port to be used by this connection. A “server” connection (tListen) will bind to this port, while a “client” connection (tConnect) will attempt to connect to this port on the server's host machine (specified by the client connection's Server parameter, page 57).</td>\n</tr>\n<tr>\n<td>LocalPort</td>\n<td>0x0000</td>\n<td>1024–65535 (0x0400–0xFFFF)</td>\n<td>An integer value (usually specified in hexadecimal) specifying the local IP port used to connect to a DLI/TSI server, such as a Freeway. The default value of 0 allows the operating system to select any unused local IP port. Since the client application uses the specified local IP port for each connection attempt using a given TSI connection definition, this parameter can be used to force a Freeway to terminate a connection which was not terminated normally (for example, if the client machine crashed without properly closing its sockets, or if the client machine closed its sockets while the network was physically disconnected).</td>\n</tr>\n</tbody>\n</table>\n3.3.4 Parameters for Connection Definition (Shared-Memory Transport)\n\nThe TSI configuration parameters required for a VxWorks shared-memory transport connection (server-resident applications) are shown alphabetically in Table 3-4, along with the defaults. You need to include only those parameters whose values differ from the defaults. See Section 3.4.2 for an example.\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Default</th>\n<th>Valid Values</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>ShmKey</td>\n<td>n/a</td>\n<td>n/a</td>\n<td>Reserved.</td>\n</tr>\n<tr>\n<td>ShmMaxInQ</td>\n<td>10</td>\n<td>2–1000</td>\n<td>An integer value specifying the size of the TSI internal shared-memory input queue. It is recommended that this parameter value match the value of the connection's MaxInQ parameter (page 56).</td>\n</tr>\n<tr>\n<td>ShmMaxOutQ</td>\n<td>10</td>\n<td>2–1000</td>\n<td>An integer value specifying the size of the TSI internal shared-memory output queue. It is recommended that this parameter value match the value of the connection's MaxOutQ parameter (page 56).</td>\n</tr>\n<tr>\n<td>ShmPeerName</td>\n<td>no default</td>\n<td>string (ð 20)</td>\n<td>A string of characters specifying the connection-name of a TSI "server" connection (tListen) to which this "client" connection wishes to connect. This parameter is used in conjunction with the connection's Server parameter (page 57) in establishing a "shared-memory" connection.</td>\n</tr>\n</tbody>\n</table>\n3.4 Example TSI Configurations\n\nThis section describes the supported transport interfaces. Because TSI was intended to shield the application from any transport interface dependencies, the same application can be run over different transport interfaces; the user needs to modify only the application’s TSI configuration file. The application might need to make modifications due to operating system dependencies (especially under VxWorks); however, the interface to TSI should remain basically constant. Recall that TSI applications “connect” using the tConnect and tListen calls which take a connection-name (associated with a connection definition) as a parameter. The transport-specific parameters within each connection definition control this connection process.\n\n3.4.1 TCP/IP Socket Transport Interface\n\nTo configure a TSI connection to use the TCP/IP socket transport interface, the connection definition’s Transport parameter (page 57) must have the value “tcp-socket”. The TCP/IP socket-specific parameters (see Table 3–3 on page 58) include:\n\n- WellKnownPort\n- LocalPort\n- TCPKeepAlive\n- TCPNoDelay\n\nThe WellKnownPort parameter along with the Server parameter (page 57) specify a “connection point.” Assume that we have two TSI applications executing on two machines connected by a TCP/IP network. An example would be the two applications labeled Client1 and Server or the two applications labeled Client2 and Server in Figure 1–5 on page 27.\n\nA possible TSI configuration for the two applications is shown in Figure 3–2. “Server” application X (connection-name “TCPserver”) wishes to listen for an incoming connection, while “client” application Y (connection-name “TCPclient”) wishes to connect to “server” application X.\nNotice the following points regarding the two TSI configuration files in Figure 3-2:\n\n- The “server” application performing the `tListen` call (application X) needs to specify only the `WellKnownPort` parameter in the TSI configuration file, not the `Server` parameter. This is because the “server” TSI software automatically uses the address of the machine on which it is running.\n\n- The “client” application performing the `tConnect` call (application Y) specifies the `Server` parameter as the host name (or IP address) of the remote machine as well.\nas the WellKnownPort parameter to which the remote application is bound. If the “client” application Y needs to connect to a similar “server” application running on a different machine, only the Server and WellKnownPort parameters of the “TCPclient” connection definition must be modified.\n\nUsing the Figure 3–2 connection definitions, the “server” application X would call tListen using the connection-name “TCPserver”:\n\n```\nID = tListen (\"TCPserver\", funcptr);\n```\n\nThe “client” application Y would call tConnect using the connection-name “TCPclient”:\n\n```\nID = tConnect (\"TCPclient\", funcptr);\n```\n\n### 3.4.2 Shared-Memory Transport Interface (VxWorks Only)\n\nTo configure a TSI connection to use the shared-memory transport interface, the connection definition’s Transport parameter (page 57) must have the value “shared-memory”. The shared-memory-specific parameters (see Table 3–4 on page 59) include:\n\n- ShmMaxInQ\n- ShmMaxOutQ\n- ShmPeerName\n- ShmKey\n\nThe ShmPeerName parameter along with the ServerName “main” parameter (page 55) specify a “connection point.” Assume that we have two TSI applications (“server” and “client”) executing as in the previous TCP/IP example; however, shared-memory applications must be running on the same machine under VxWorks. An example would be the two applications labeled **Client3** and **Server** in Figure 1–5 on page 27.\n\nA possible TSI configuration for each application is shown in Figure 3–3. “Server” application X (connection-name “SHM server”) wishes to listen for an incoming connection, while “client” application Y (connection-name “SHM client”) wishes to connect to “server” application X.\nNotice the following points regarding the two TSI configuration files in Figure 3-3:\n\n- The **Server** parameter is used to match a peer TSI shared-memory application, and its value must match the value of the peer's **ServerName** parameter.\n• The ShmPeerName parameter is used to match a particular connection definition (connection-name) in the peer’s configuration file.\n\nUsing the Figure 3-3 connection definitions, the “server” application X would call tListen using the connection-name “SHM server”:\n\n ID = tListen (\"SHMserver\", funcptr);\n\nThe “client” application Y would call tConnect using the connection-name “SHM client”:\n\n ID = tConnect (\"SHMclient\", funcptr);\n3.5 Protogate's Freeway Server TSI Configuration\n\nDuring the software installation procedures described in the Freeway User Guide, the default Protogate server TSI configuration file named MuxCfg (see Figure 3–4) was installed in the freeway/boot directory on the boot server. Freeway uses the information in the MuxCfg file to configure the Protogate server-resident TSI software so it can communicate (using the Freeway message multiplexor) with the client TSI software. Refer back to Figure 1–5 on page 27 to see the server TSI software relative to the Freeway message multiplexor.\n\nThere is one critical difference in the Protogate server TSI software, namely that it must use TSI non-blocking I/O support (that is, the AsyncIO parameter must be set to “yes”, as shown in Figure 3–4). Changing the AsyncIO parameter to “no” or omitting it, will prevent the Protogate server TSI software from operating as designed.\n\n---\n\n**Caution**\n\nBefore modifying the MuxCfg file for the Protogate server TSI software, you should be familiar with the parameter descriptions in Table 3–1 through Table 3–4 (page 54 through page 59). Of particular importance are those parameters that control server resources, such as the TSI buffer pool size (MaxBuffers parameter on page 54) or message size (MaxBufSize parameter on page 55). Improper values could adversely affect server operation.\n\nAlso keep the following points in mind if you must modify the MuxCfg file:\n\n- The Transport parameter (page 57) has no default and must be defined.\n- Unlike a client TSI configuration file (such as shown in Figure 3–2 on page 61), the Server parameter (page 57) is not required for MuxCfg because the server TSI software automatically uses the address of the machine on which it is running.\n- The parameters can appear in any order in the configuration file and can be upper-case, lower-case, or a mixture.\n- If a parameter is not explicitly contained in the file, the default is used (defaults are identified in Figure 3–4).\n// Default TSI configuration file for the Protogate server-resident software:\n//\n// Date Initials Abstracts\n// 12may94 pmt Original coding...\n//\n// Note that the parameters commented as default could have been omitted\n//\nmain\n{\n AsyncIO = \"yes\"; // must be specified as yes\n LogLev = 0; // default\n MaxBuffers = 2048;\n MaxConns = 128; // default\n MaxBufSize = 1024; // default\n StackSize = 10240; // default\n TraceName = \"/ram1/msgmux.trc\";\n TraceSize = 64000;\n TraceLev = 3;\n}\n\nserver1 // connection-name\n{\n AsyncIO = \"yes\"; // must be specified as yes\n LogLev = 0;\n MaxBufSize = 1024; // default\n MaxErrors = 10; // default\n MaxInQ = 10; // default\n MaxOutQ = 10; // default\n TCPKeepAlive = \"no\"; // default\n TCPNoDelay = \"no\"; // default\n Timeout = 63999;\n TraceLev = 3;\n Transport = \"tcp-socket\"; // must be specified (no default)\n WellKnownPort = 0x'2010'; // default\n}\n\nFigure 3-4: TSI Configuration File (MuxCfg) for Protogate Server-Resident TSI\n3.6 Miscellaneous TSI Configuration Details\n\nAfter you are familiar with the fundamentals of working with the tsicfg preprocessor program, the additional details described in this section might be of interest.\n\n3.6.1 TSI Configuration Error Messages\n\nThe TSI configuration preprocessor, tsicfg, can display one of the following error or warning messages:\n\nInvalid type specified — STRING expected Your parameter value does not match the expected type. Action: Review your configuration source code for errors, and try again.\n\nInvalid type specified — BOOLEAN expected You must use a Boolean value (“YES” or “NO”) for this parameter. Action: Review your configuration source code for errors and try again.\n\nInvalid type specified — DEC/HEX/OCT expected The expected type is decimal, hexadecimal, or octal data format. Action: Review your configuration source code for errors and try again.\n\nInvalid type specified — FLOAT expected The expected type is floating point format. Action: Review your configuration source code for errors and try again.\n\nInvalid range specified The provided parameter value is out of range. Action: Review your configuration source code for errors and try again.\n\nInternal error! This is an internal error in the tsicfg program. Action: Rerun tsicfg with your source file. If this error consistently occurs, save your configuration source code and contact Protogate for further assistance.\n\nNo “main” — Default is used This is a warning message that your configuration source code does not have the “main” section specified as the first entry in the\nconfiguration source code. Action: None if you do not wish to define the “main” section yourself. Otherwise, consider adding the “main” section as the very first section in the text configuration file.\n\n**Redefined “main” — Definition ignored** This is a warning message that either you defined the “main” section twice or that you did not code the “main” section as the very first entry in your text configuration file. Action: Review your text configuration file, correct the problem, and rerun tsicfg.\n\n**Invalid transport name** You specified a protocol name that is not supported by the TSI. Action: Review your text configuration file and this manual for the supported transport protocols. Correct the error and try again.\n\n**Undefined parameter name** The provided parameter name is not defined. Action: Review your configuration source code for errors and try again.\n\n**Invalid parameter for specified protocol** This parameter does not belong to this protocol. Action: Review your configuration source code for errors and try again.\n\n**Failed processing file** tsicfg failed to complete processing your configuration file. Action: Review your configuration source code for errors and try again.\n\n**syntax error - cannot backup** This is an internal LEX/YACC error. Action: Retry the operation.\n\n**out of memory** This is an internal LEX / YACC error. Action: Retry the operation.\n\n**yacc stack overflow** This is an internal YACC error. Action: Retry the operation.\n\n**syntax error** A syntax error was encountered in your configuration source code. Action: Locate and correct the error and try the operation again.\n3.6.2 Protogate Definition Language (PDL) Grammar\n\nThe following extended BNF metalanguage describes the language used to create the TSI text configuration file. The following is a brief description of the symbols used:\n\n1. A string inside of <> is a non-terminal symbol. Its definition is located somewhere down the list.\n\n2. Strings inside of {} separated by a vertical bar (|) make up a list of options. You can select one or none of the options.\n\n3. A string inside of [] is an optional string.\n\n4. Terminal symbols are those not surrounded by <>.\n\nContext Free Grammar\n\n```\n<config_entry> ::= <connection_name> <leftbr> <config_stmt_list> <rightbr>\n<connection_name> ::= <identifier>\n<config_stmt_list> ::= <config_stmt>{<config_stmt_list>}\n<config_stmt> ::= [<parameter_name> <equal><parameter_value>;\n<parameter_name> ::= <identifier>\n<parameter_value> ::= {<string> | 0x<hex> | <decimal> | 0<octal>\n0b<binary> | <float> }\n<string> ::= <doublequote><str><doublequote>\n<str> ::= [<char>{<str> }]\n<decimal> ::= <decdigit>[<decimal>]\n<octal> ::= <octdigit>[<octal>]\n<binary> ::= <bindigit>[<binary>]\n<hex> ::= <hexdigit>[<hex>]\n<float> ::= <decimal>.<decimal>\n<equal> ::= =\n<leftbr> ::= {\n<rightbr> ::= }\n<doublequote> ::= \"\n```\n<char> ::= 1…255\n<decdigit> ::= 0…9\n<hexdigit> ::= <decdigit>, a–f\n<octdigit> ::= 0…7\n<bindigit> ::= 0…1\n<alpha> ::= a–z, A–Z, _\n<digit> ::= <decdigit>\n<identifier> ::= <alpha>[<restid>]\n<restid> ::= <alphadigit>[<restid>]\n<alphadigit> ::= <alpha> | <digit>\nIn this document, the term “Freeway” can mean either a Freeway server or an embedded ICP. For the embedded ICP, also refer to the user guide for your ICP and operating system (for example, the ICP2432 User Guide for Windows NT).\n\n4.1 Overview of TSI Functions\n\nThis chapter describes the transport subsystem interface (TSI) functions used by your application program to interface to Protogate’s Freeway communications server. The TSI is provided as a C library to be linked with your application program. Section 4.1.3 describes TSI data structures that the application programmer uses with the TSI. Table A–1 on page 137 summarizes the error codes related to the TSI functions.\n\n4.1.1 TSI Error Handling\n\nThe tserrno variable is globally available to your application and offers similar services to errno provided in the C language. The TSI uses tserrno to store all its error codes. Your application should check this value on all returns from TSI function calls. Applicable error codes are listed with each function call described in this chapter. Appendix A gives a complete list of TSI error codes.\n\nWhile developing your TSI application, if a particular error occurs consistently, contact Protogate for further assistance.\n4.1.2 Categories of TSI Functions\n\nThe TSI library can be categorized as shown in Table 4–1.\n\nTable 4–1: TSI Function Groups\n\n<table>\n<thead>\n<tr>\n<th>Category</th>\n<th>TSI Functions</th>\n<th>Usage</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Preparation and termination</td>\n<td>tInit, tTerm</td>\n<td>Initialize and terminate TSI services</td>\n</tr>\n<tr>\n<td>Connection handling</td>\n<td>tConnect, tListen, tDisconnect</td>\n<td>Establish and terminate a connection with a peer TSI application</td>\n</tr>\n<tr>\n<td>Data transfer</td>\n<td>tRead, tWrite, tPoll, tPost(^1), tSyncSelect</td>\n<td>Exchange data with a peer TSI application and obtain specific information related to your connection</td>\n</tr>\n<tr>\n<td>Buffer management</td>\n<td>tBufAlloc, tBufFree</td>\n<td>Obtain and release fixed-size TSI buffers</td>\n</tr>\n</tbody>\n</table>\n\n\\(^1\\) Server-resident application only\n4: TSI Functions\n\n4.1.2.1 Summary of TSI Functions\n\nThe TSI functions used in writing a client application are presented alphabetically in Section 4.2 through Section 4.13. For easy reference after you are familiar with the details of each function call, Table 4-2 summarizes the TSI function syntax and parameters, listed in the most likely calling order.\n\n**Caution**\n\nWhen using non-blocking I/O, there must always be at least one tRead request queued to avoid loss of data or responses from the ICP.\n\nAn overview of using the TSI functions is:\n\n- Start up communications (tInit, tConnect, tBufAlloc)\n- Send requests and data using tWrite\n- Receive responses using tRead\n- For blocking I/O, use tSyncSelect to query read availability status for multiple connections\n- For non-blocking I/O, handle I/O completions at the software interrupt level in the completion handler established by the tInit or tConnect function, or by periodic use of tPoll to query the I/O completion status.\n\nShut down communications (tBufFree, tDisconnect, tTerm)\nTable 4-2: TSI Functions: Syntax and Parameters (Listed in Typical Call Order)\n\n<table>\n<thead>\n<tr>\n<th>TSI Function</th>\n<th>Parameter(s)</th>\n<th>Parameter Usage</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>int tInit</td>\n<td>(char *cCfgFile, char *pUsrCB, int (*fUsrIOCH)(char *pUsrCB));</td>\n<td>TSI binary configuration file name</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Optional I/O complete control block</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Optional IOCH and parameter</td>\n</tr>\n<tr>\n<td>int tConnect</td>\n<td>(char *cTransportName, int (*fUsrIOCH)(char *pUsrCB, int iConnID));</td>\n<td>TSI connection definition entry</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Optional I/O completion handler</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Parameters for IOCH</td>\n</tr>\n<tr>\n<td>int tPost</td>\n<td>(void);</td>\n<td></td>\n</tr>\n<tr>\n<td>int tListen</td>\n<td>(char *cTransportName, int (*fUsrIOCH)(char *pUsrCB, int iConnID));</td>\n<td>TSI connection definition entry</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Optional I/O completion handler</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Parameters for IOCH</td>\n</tr>\n<tr>\n<td>int tPoll</td>\n<td>(int iConnID, int iPollType, char **ppBuf, int *piBufLen, char *pStat);</td>\n<td>Connection ID (tConnect/tListen)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Request type</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Poll-type dependent parameter</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Size of I/O buffer (bytes)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Status or configuration buffer</td>\n</tr>\n<tr>\n<td>char *tBufAlloc</td>\n<td>(void);</td>\n<td></td>\n</tr>\n<tr>\n<td>int tRead</td>\n<td>(int iConnID, char **ppBuf, int iBufLen);</td>\n<td>Connection ID (tConnect/tListen)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Buffer to receive data</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Maximum bytes to be returned</td>\n</tr>\n<tr>\n<td>int tWrite</td>\n<td>(int iConnID, char *pBuf, int iBufLen, int iWritePriority);</td>\n<td>Connection ID (tConnect/tListen)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Source buffer for write</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Number of bytes to write</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Normal or expedite write</td>\n</tr>\n</tbody>\n</table>\nTable 4-2: TSI Functions: Syntax and Parameters (Listed in Typical Call Order)\n\n<table>\n<thead>\n<tr>\n<th>TSI Function</th>\n<th>Parameter(s)</th>\n<th>Parameter Usage</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>int tSyncSelect</td>\n<td>(int iNbrConnID, int connIDAry[], int readStatArray[])</td>\n<td>Number of connection IDs</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Packed array of connection IDs</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Array containing read status for IDs</td>\n</tr>\n<tr>\n<td>char *tBufFree</td>\n<td>(char *pBuf);</td>\n<td>Buffer to return to pool</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>int tDisconnect</td>\n<td>(int iConnID, int iDiscType)</td>\n<td>Connection ID (tConnect/tListen)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Mode (normal or force)</td>\n</tr>\n<tr>\n<td>int tTerm</td>\n<td>(void);</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n4.1.3 TSI Data Structures\n\nThis section describes the following TSI data structures that your application can access using the tPoll function.\n\n- TSI system configuration structure\n- TSI connection status structure\n- TSI connection definition list\n\n4.1.3.1 TSI System Configuration\n\nAfter initializing the TSI services (tInit), your application can obtain system configuration parameters from TSI by calling tPoll with the TSI_POLL_GET_SYS_CFG option (Section 4.8). The information includes the size of buffers in the TSI data pool and the overhead TSI uses for header storage. This information is useful if your application uses its own buffers instead of TSI buffer management's. Your application receives the system configuration information in the data structure shown in Figure 4-1. Table 4-3 describes the fields.\n\n```c\ntypedef struct _TSI_SYS_CFG {\n int iMaxBufSize;\n unsigned short usMaxConns;\n unsigned short usMaxBufs;\n unsigned short usNumActiveConns;\n unsigned short usNumBufsUsed;\n unsigned short usNumBufsAvail;\n unsigned short usOverhead;\n unsigned short usVersion;\n unsigned short usRevision;\n BOOLEAN tfAsyncIO;\n unsigned char cTraceFileName[TSI_MAX_NAME];\n} TSI_SYS_CFG;\n```\n\n**Figure 4-1:** TSI System Configuration Data Structure\nTable 4-3: TSI System Configuration Data Structure Fields\n\n<table>\n<thead>\n<tr>\n<th>Field</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>iMaxBufSize</td>\n<td>The maximum area available for user data in buffers from the TSI buffer pool.</td>\n</tr>\n<tr>\n<td>usMaxConns</td>\n<td>The maximum number of connections that can be active simultaneously. This value is configurable using the MaxConns TSI configuration parameter (page 55) in the “main” configuration section.</td>\n</tr>\n<tr>\n<td>usMaxBufs</td>\n<td>The maximum number of buffers available for your application. This value is configurable using the MaxBuffers TSI configuration parameter (page 54) in the “main” configuration section.</td>\n</tr>\n<tr>\n<td>usNumActiveConns</td>\n<td>The number of connections currently in use. This number should be less than or equal to usMaxConns.</td>\n</tr>\n<tr>\n<td>usNumBufsUsed</td>\n<td>The number of buffers currently in use. This number should be less than or equal to usMaxBufs.</td>\n</tr>\n<tr>\n<td>usNumBufsAvail</td>\n<td>The number of buffers currently available for use. This number plus usNumBufsUsed should be equal to usMaxBufs.</td>\n</tr>\n<tr>\n<td>usOverhead</td>\n<td>The number of additional bytes that must precede your data area in a buffer that your application requests the TSI to read or to write. Your application needs to be aware of this value only if it does not wish to use the TSI buffer management scheme. This value, usOverhead + iMaxBufSize, must be equal to the MaxBufSize TSI configuration parameter (page 55).</td>\n</tr>\n<tr>\n<td>usVersion</td>\n<td>The current version of the TSI. You must know this number when you call Protogate's customer support.</td>\n</tr>\n<tr>\n<td>usRevision</td>\n<td>The current revision of the TSI.</td>\n</tr>\n<tr>\n<td>tfAsyncIO</td>\n<td>A BOOLEAN value indicating whether or not the TSI was configured to use non-blocking I/O (zero specifies blocking I/O).</td>\n</tr>\n<tr>\n<td>cTraceFileName</td>\n<td>The name of the file the TSI uses to trace the data that flows through the layer.</td>\n</tr>\n</tbody>\n</table>\n4.1.3.2 TSI Connection Status\n\nAfter establishing a connection, your application can obtain connection-related information by calling tPoll with the TSI_POLL_GET_CONN_STATUS option (Section 4.8). This information includes the negotiated buffer size (usMaxConnBufSize), which is the actual data size available for this connection’s user data. Your application receives the connection status information in the TSI_CONN_STAT data structure shown in Figure 4–2. Table 4–4 describes the fields.\n\n```\ntypedef struct _TSI_CONN_STAT\n{\n short iQReadSize;\n short iQWriteSize;\n short iQNumRead;\n short iQNumWrite;\n short iQNumReadDone;\n short iQNumWriteDone;\n short iConnStatus;\n short iNumErrors;\n short iMaxErrors;\n short usMaxConnBufSize\n short iNumCalls;\n BOOLEAN tfOverflow\n} TSI_CONN_STAT;\n```\n\n**Figure 4–2: TSI Connection Status Data Structure**\n\n### 4.1.3.3 TSI Connection Definition List\n\nThe connection definition list is returned to your application if it invokes tPoll with the TSI_POLL_GET_CFG_LIST option. The configuration list is returned through the ppBuf argument, and the number of the connection definitions is given by the piBufLen argument. Refer to tPoll, Section 4.8, for information on this list of connection definitions.\n\n*Note* Refer to the Freeway Data Link Interface Reference Guide for an example program to request DLI session status. Requesting TSI connection status is similar.\n### Table 4-4: TSI Connection Status Data Structure Fields\n\n<table>\n<thead>\n<tr>\n<th>Field</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>iQReadSize</td>\n<td>The size of the input queue. This value can be configured using the MaxInQ TSI configuration parameter (page 56) in the connection definition section.</td>\n</tr>\n<tr>\n<td>iQWriteSize</td>\n<td>The size of the output queue. This value can be configured using the MaxOutQ TSI configuration parameter (page 56) in the connection definition section.</td>\n</tr>\n<tr>\n<td>iQNumRead</td>\n<td>The current number of read requests in the read queue. This value is less than or equal to iQReadSize.</td>\n</tr>\n<tr>\n<td>iQNumWrite</td>\n<td>The current number of write requests in the write queue. This value is less than or equal to iQWriteSize.</td>\n</tr>\n<tr>\n<td>iQNumReadDone</td>\n<td>The current number of read requests that are complete or timed out in the input queue. This value is less than or equal to iQReadSize.</td>\n</tr>\n<tr>\n<td>iQNumWriteDone</td>\n<td>The current number of write requests that are complete or timed out in the output queue. This value is less than or equal to iQWriteSize.</td>\n</tr>\n<tr>\n<td>iConnStatus</td>\n<td>The current status of the connection. The valid connection status values are: TSI_STATE_NOT_CONNECTED The current TSI connection is being ended. TSI_STATE_NOT_IN_USE The current TSI connection is not available for use because it failed to establish a connection or has finished disconnecting. A cleanup is underway. TSI_STATE_NOT_CONNECTED The TSI is still trying to establish a connection with Freeway or the peer TSI application. TSI_STATE_CONNECTED The TSI successfully established a connection with Freeway or the peer TSI application. Your application can now read or write to this connection.</td>\n</tr>\n<tr>\n<td>iNumErrors</td>\n<td>The current number of I/O errors that has occurred for this connection since the connection was established. Your application can monitor this value to check the health of an active connection.</td>\n</tr>\n<tr>\n<td>iMaxErrors</td>\n<td>The maximum number of errors this connection can tolerate before it rejects I/O requests from your application. This value can be defined using the MaxErrors TSI configuration parameter (page 56) in the connection definition section.</td>\n</tr>\n<tr>\n<td>usMaxConnBufSize</td>\n<td>The maximum buffer area available to the user for the transfer of data. The value can vary between connections, and the value is valid only after the connection is established. This size does not include any TSI overhead requirements.</td>\n</tr>\n<tr>\n<td>iNumCalls</td>\n<td>Reserved</td>\n</tr>\n<tr>\n<td>tfOverflow</td>\n<td>Reserved</td>\n</tr>\n</tbody>\n</table>\n4.2 tBufAlloc\n\nThe tBufAlloc function allocates a fixed-size buffer that is maintained by TSI services. Your application can use these buffers to exchange data with peer TSI applications or for any other purpose. To avoid a buffer depletion problem, your application must return all unused buffers to TSI using tBufFree (Section 4.3).\n\nThough you are not required to use tBufAlloc, you should consider using it for all TSI I/O operations for the following reasons:\n\n- The TSI buffer services account for buffer overhead requirements.\n- The TSI allocates all buffers up front, resulting in better real-time performance than the normal C malloc and free functions\n- The number of TSI buffers is configurable for operating environments with limited system resources (MaxBuffers, page 54)\n\nTo enhance performance, the TSI implementation uses the memory area just before the data area to store its headers. Due to this implementation, if your application does not wish to use the TSI buffer management, it must allocate sufficient memory for not only its data but also the TSI headers. To obtain the amount of memory required for the TSI overhead, your application can invoke tPoll with the TSI_POLL_GET_SYS_CFG option (usOverhead field on page 77). Your application can also use tPoll with the TSI_POLL_GET_SYS_CFG option to obtain the status of buffer management (see Table 4-3 on page 77). Refer to Section 2.3 on page 31 for more information on buffer management issues.\n\nSynopsis\n\n```c\nchar *tBufAlloc ( void );\n```\n\nParameters\n\nNone\nReturns\n\nIf the `tBufAlloc` function completes successfully, it returns an address that points to the buffer area to be used by your application. Note that the address returned is the address of the data area of the TSI buffer; this address must be used by any further manipulations on the buffer such as `tRead`, `tWrite`, `tPoll`, and `tBufFree`. Otherwise it returns `NULL`, and `tserrno` contains one of the following error codes (listed alphabetically):\n\n- **TSI_BUFA_ERR_NEVER_INIT** The TSI was never initialized; that is, `tInit` was never called.\n \n **Action:** Review your application and try again.\n\n- **TSI_BUFA_ERR_NO_BUFS** The TSI exhausted buffers. Possible problems are:\n (1) your application did not release buffers after use, or (2) your application is configured for non-blocking I/O, and it has too many outstanding connections with a large queue size (for example, `MaxBuffers = 1000`, 10 outstanding connections, and each has 100 entries in the queue).\n\n **Action:** Severe error; consider increasing the number of buffers in the TSI configuration file (`MaxBuffers` on page 54). Review your application and make sure it releases unused buffers to the TSI.\n\n- **TSI_BUFA_ERR_SEVERE_ERR** The TSI internal call to `QAdd` failed.\n\n **Action:** If this error occurs consistently, contact Protogate for assistance.\n\nFor additional error codes, refer to Appendix A.\n4.3 tBufFree\n\nYour application must use tBufFree to release the TSI buffers that it allocated using tBufAlloc. It must also release any read buffer that TSI allocated in tRead (Section 4.10). The buffer is returned to the TSI internal free buffer pool. It is the responsibility of your application to prevent buffer depletion by releasing the unused TSI buffers.\n\nSynopsis\n\n```c\nchar *tBufFree ( char *pBuf ); /* Buffer to return to buffer pool */\n```\n\nParameters\n\n- `char *pBuf` This field contains the data address of the TSI buffer that was returned by tBufAlloc (or that was allocated by tRead).\n\nReturns\n\nIf the tBufFree function completes successfully, it returns the value of pBuf. Otherwise it returns NULL, and tserrno contains one of the following error codes (listed alphabetically):\n\n- **TSI_BUFF_ERR_INVALID_BUF** The buffer pointer provided to tBufFree is either NULL or -1.\n \n Action: Review your application and try again.\n\n- **TSI_BUFF_ERR_NEVER_INIT** The TSI was never initialized; that is, tInit is never called.\n \n Action: Review your program and try again.\n\n- **TSI_BUFF_ERR_NOT_ALLOCATED** The TSI invoked tBufFree to free a buffer and the buffer is not allocated.\nAction: Make sure that your application frees only a TSI buffer and that it frees it only once. Review your application and try again.\n\n**TSI_BUFF_ERR_SEVERE_ERR** The TSI invoked `tBufFree` to free a buffer and either the buffer pool is empty or the buffer does not belong to the TSI.\n\nAction: Review your application and try again.\n\nFor additional error codes, refer to Appendix A.\n4.4 tConnect\n\nThe tConnect function establishes a connection to a peer TSI application. The connection parameters are provided through the TSI configuration file. The TSI searches its configuration file for a match of the connection name provided as the first parameter of this function call. Once found, the TSI loads the connection parameters into memory and begins to establish a connection with the peer TSI application. The destination is part of the TSI connection parameters.\n\nFor non-blocking I/O, tConnect returns as soon as it detects a potential blocking condition. Your application is not blocked while the TSI attempts to complete the connection request. When the connection is made, the TSI calls one or both of the IOCH functions provided through the tInit and tConnect calls. If no IOCH functions are provided, none is called. Either tInit or tConnect can be used to supply the IOCH; however, the tConnect IOCH requires a connection ID, and is called for that particular connection only.\n\nYour application uses the iConnID returned from this call for all other TSI calls (tRead, tWrite, and so on). If this connection is configured for non-blocking I/O, you must ensure that the connection is fully established before you call the tRead, tWrite, or tDisconnect functions.\n\n---\n\nNote\n\nIf you need to request connection status to obtain the maximum buffer size (which may change due to negotiation procedures during tConnect), your application should wait until after a successful tConnect before calling tPoll with the TSI_POLL_GET_SESS_STATUS option (Section 4.1.3.2 on page 78). See Section 2.3.2.3 on page 39 for details of the negotiation process.\n\nIf your application did not previously call tInit, tConnect makes the tInit call. The default values are used.\nSynopsis\n\nint tConnect (char *cTransportName, /* TSI connection definition entry name */\n int (*fUsrIOCH) (char *pUsrCB, int iConnID));\n/* Optional IOCH for specific connection */\n\nParameters\n\nchar *cTransportName A string of characters that specifies the name of the desired connection definition entry in the TSI binary configuration file. The associated configuration entry defines the characteristics of the connection you are about to make.\n\nint (*fUsrIOCH) (char *pUsrCB, int iConnID) This field should contain the address of the I/O completion handler (IOCH) that the TSI invokes immediately after it services an I/O condition for this connection. The IOCH is invoked by the TSI only if this connection is configured for non-blocking I/O. You must write the IOCH yourself. When an I/O condition occurs for this connection, the TSI invokes this IOCH with the pUsrCB value (that you provided through tInit) and the connection ID returned by this call. You can provide a different fUsrIOCH for each connection ID or use the same fUsrIOCH for all IDs. If your application does not wish the TSI to invoke your IOCH, this parameter should be NULL.\n\nReturns\n\nThe tConnect function returns a connection ID or ERROR. The connection ID can have a value from zero to the maximum number of connections (MaxConns parameter, page 55) minus one. If the connection definition for the function parameter cTransportName specifies blocking I/O, a returned connection ID indicates that the connection has completed successfully. If the connection definition specifies non-blocking I/O and a connection ID is returned, the application must examine tserrno and invoke tPoll with the TSI_POLL_GET_CONN_STATUS option to determine when the connection has successfully completed. If the connection has not completed upon return, tserrno is set to TSI_EWOULDBLOCK.\nIf the tConnect function returns ERROR, the connection failed, and your application must check tserrno which contains one of the following error codes (listed alphabetically):\n\n- **TSI_CONN_ERR_CLOSE_FAILED** The TSI failed to close its transport-dependent connection when it failed to complete the connection request.\n \n **Action:** If this error occurs consistently, contact Protogate for assistance.\n\n- **TSI_CONN_ERR_CONN_INIT_FAILED** TSI failed to initialize a connection entry for your application.\n \n **Action:** Check the TSI connection configuration.\n\n- **TSI_CONN_ERR_INVALID_PROT** The transport parameter in the connection definition of the TSI configuration file is not valid.\n \n **Action:** Check whether your configuration program, tsicfg, is at the same level as your library.\n\n- **TSI_CONN_ERR_INVALID_STATE** The TSI encountered an invalid state in its state processing machine.\n \n **Action:** If this error occurs consistently, contact Protogate for assistance.\n\n- **TSI_CONN_ERR_OPEN_FAILED** The TSI failed to establish a transport-dependent connection to the peer TSI application.\n \n **Action:** Terminate your application and review your TSI configuration file.\n\n- **TSI_CONN_ERR_QADD_FAILED** The TSI failed to insert its internal request in the internal I/O queue.\n \n **Action:** Severe error; terminate your application and try again.\nTSI_CONN_ERR_RETRY_EXCEEDED The TSI retry count exceeded its limit.\n\nAction: Terminate your application and review your configuration parameter for this connection.\n\nTSI_CONN_ERR_SOCK_ALLOC_FAILED The TSI failed to allocate the resources necessary to support the connection.\n\nAction: Review your connection configuration parameters. You can also review your error log for additional information.\n\nTSI_CONN_ERR_TINIT_FAILED The TSI failed to initialize its services. This error occurs only if your application does not explicitly call the tInit function.\n\nAction: Check your binary configuration file. If the default binary configuration file (tsicfg.bin) was used by the TSI, verify its existence.\n\nTSI_EWOULDBLOCK The requested action could not be completed immediately. The TSI would have blocked this operation if your connection was using blocking I/O.\n\nAction: Use tPoll to check whether your request completed. You can program your application to be notified by one of the I/OCH routines that you provided when you invoked the tInit, tConnect, or tListen function. Refer to Appendix B for information on managing TSI applications using non-blocking I/O.\n\nFor additional error codes, refer to Appendix A.\n4.5 tDisconnect\n\nThe tDisconnect function terminates an active connection between your application and the peer TSI application.\n\nIf this connection is configured for non-blocking I/O, the application must examine tserrno and invoke tPoll with the TSI_POLL_GET_CONN_STATUS option to determine when the connection has been successfully disconnected.\n\nIt is suggested that your application perform I/O cleanup and then issue a Normal tDisconnect request to the TSI. Issuing tTerm while active connections exist should be the last option.\n\nSynopsis\n\n```c\nint tDisconnect ( \n int iConnID, /* Connection ID from tConnect|tListen */ \n int iDiscType ); /* Disconnect mode (normal or force) */\n```\n\nParameters\n\n- **int iConnID** The connection ID is provided by the TSI through the tConnect or tListen function call. This ID uniquely identifies a TSI connection between your application and the peer TSI application.\n\n- **int iDiscType** This parameter allows your application to request the TSI to terminate an active connection in either of the following close modes (whether the connection is using blocking or non-blocking I/O):\n \n TSI_DISC_FORCE When your application issues a Force disconnect for an active connection, the TSI empties the I/O queues and proceeds with the disconnect process without considering the status of the I/O queues. Note that when your application issues a tTerm while active connections exist, the TSI itself issues a Force disconnect request before it frees the TSI service structure.\nTSI_DISC_NORMAL The TSI rejects a Normal disconnect request if its internal input and output queues contain outstanding I/O requests. Your application should consider checking the I/O queue prior to calling tDisconnect with this mode. You can obtain the status of I/O queues using the tPoll call.\n\nReturns\n\nIf the tDisconnect function completes successfully, it returns OK. Otherwise, it returns ERROR, and tserrno contains one of the following error codes (listed alphabetically):\n\nTSI_DISC_ERR_CLOSE_FAILED The TSI failed to close the listener.\n\nAction: Severe error; if this error occurs consistently, contact Protogate for assistance.\n\nTSI_DISC_ERR_DISC_FAILED The disconnect failed and the connection has been returned to the connected state.\n\nAction: If this error occurs consistently, contact Protogate for assistance.\n\nTSI_DISC_ERR_INVALID_ID The provided connection ID is invalid.\n\nAction: Review your program's logic. If this error occurs consistently, contact Protogate for assistance.\n\nTSI_DISC_ERR_INVALID_STATE The TSI encountered an invalid state in its state processing machine.\n\nAction: Review the TSI trace and error logs. If this error occurs consistently, contact Protogate for assistance.\n\nTSI_DISC_ERR_INVALID_TYPE Invalid disconnect type requested (use TSI_DISC_NORMAL or TSI_DISC_FORCE).\n\nAction: Review your program's logic.\nTSI_DISC_ERR_NEVER_INIT The TSI was never initialized. You must invoke tInit before using this function.\n\nAction: Correct your program's logic and try again.\n\nTSI_DISC_ERR_Q_NOT_EMPTY Your application requested a normal disconnect on a given connection, and the internal I/O queues for that connection are not empty.\n\nAction: Review your program's logic, and try again.\n\nTSI_DISC_ERR_QADD_FAILED The TSI failed to add the disconnect packet to its internal queue.\n\nAction: If this error occurs consistently, contact Protogate for assistance.\n\nTSI_DISC_ERR_SEVERE_ERROR The TSI failed to access its internal I/O queues.\n\nAction: Severe error; terminate your application and try again.\n\nTSI_EWOULDBLOCK The requested action could not be completed immediately. The TSI would have blocked this operation if your connection was using blocking I/O.\n\nAction: Use tPoll to check whether your request completed. You can program your application to be notified by one of the IOCH routines that you provided when you invoked the tInit, tConnect, or tListen function. Refer to Appendix B for information on managing TSI applications using non-blocking I/O.\n\nFor additional error codes, refer to Appendix A.\n4.6 tInit\n\nThe tInit function is usually the first TSI function your application calls. It initializes the TSI services based upon the “main” definition in the TSI binary configuration file (described in Section 3.3.1 on page 54) provided through the first parameter, cCfgFile. This function call is optional; if your application does not explicitly call tInit, the tListen or tConnect function calls it implicitly, in which case the default values are used.\n\nEven though the TSI does not require your application to call tInit prior to its being used, it is suggested that your application always call tInit and tTerm. If tTerm is not called before your application ends, connection and system resources might not be released properly.\n\nSynopsis\n\n```c\n#include <tsi.h>\n\nint tInit (char *cCfgFile, /* TSI binary configuration file name */\n char *pUsrCB, /* I/O complete control block */\n int (*fUsrIOCH)(char *pUsrCB)); /* Optional IOCH */\n```\n\nParameters\n\n- **char *cCfgFile** \nThe binary configuration file that contains all TSI run-time parameters. This file results from execution of the TSI configuration program, tsicfg, upon a TSI text configuration file. If this parameter is a NULL pointer, the default file, tsicfg.bin, is used. Whether or not you supply the configuration file name, the binary configuration file must exist for the TSI to operate. An optional on-line configuration method is described in Section 3.2.4 on page 52.\n\n- **char *pUsrCB** \nThis field should contain the address of the data area that is accessible by your supplied I/O completion handler (IOCH), fUsrIOCH, below. When the TSI is configured for non-blocking I/O, it invokes your supplied IOCH function after it services an I/O condition. The TSI passes this field as the first parameter to your supplied fUsrIOCH function.\nint (*fUsrIOCH) (char *pUsrCB) This field should contain the address of the I/O completion handler (IOCH) that TSI invokes immediately after it processes all active connections. You must write the IOCH yourself. The IOCH is called only if the TSI is configured for non-blocking I/O. If your application does not wish the TSI to invoke your IOCH, this parameter should be NULL. Either \\texttt{tInit} or \\texttt{tConnect} can be used to supply the IOCH; however, the \\texttt{tConnect} IOCH requires a connection ID, and is called for that particular connection only.\n\n**Returns**\n\nIf \\texttt{tInit} completes successfully, it returns \\texttt{OK}. Otherwise it returns \\texttt{ERROR}, and \\texttt{tserrno} contains one of the following error codes (listed alphabetically):\n\n- **TSI_INIT_ERR_ACT_ADD_REM_FAILED** The TSI failed to add its internal active connection queue.\n \n Action: Check your system resources. Refer to Section 2.4 on page 44 to calculate system resources required by the TSI.\n\n- **TSI_INIT_ERR_ACT_QINIT_FAILED** The TSI failed to initialize its internal active connection queue.\n \n Action: Check your system resources. Refer to Section 2.4 on page 44 to calculate system resources required by the TSI.\n\n- **TSI_INIT_ERR_ALREADY_INIT** Your application already issued \\texttt{tInit}.\n \n Action: Review your program logic and try again.\n\n- **TSI_INIT_ERR_BUF_ADD_REM_FAILED** The TSI failed to set up its buffer pool queue.\n \n Action: Severe error; terminate your application and try again.\nTSI_INIT_ERR_BUF_QINIT_FAILED The TSI failed to initialize its buffer pool queue.\n\nAction: Check your system resources. Refer to Section 2.4 on page 44 to calculate system resources required by the TSI.\n\nTSI_INIT_ERR_CFG_LOAD_FAILED The TSI failed to load the system configuration parameters from the provided binary configuration file.\n\nAction: Check the binary configuration file used by the TSI. If your application calls tInit directly, make sure the binary configuration file containing the configuration your application provides exists. If your application does not call tInit directly, the TSI calls this function for you; make sure the default configuration file (tsicfg.bin) exists. Verify the binary file name includes a ‘.’ character. If a text file is supplied (as discussed in Section 3.2.4 on page 52), verify the file name and its existence in the current directory (where the application program is executing). Review your program logic and try again.\n\nTSI_INIT_ERR_LOG_INIT_FAILED The TSI failed to initialize its internal logging and tracing facility.\n\nAction: Check your logging-related and tracing-related parameters in the currently used TSI configuration file.\n\nTSI_INIT_ERR_NO_MEM The TSI memory initialization failed.\n\nAction: Make sure your operating environment provides sufficient memory resources for your application.\n\nTSI_INIT_ERR_NO_RESOURCE No memory resource is available for the TSI to start its services.\n\nAction: Make sure your operating environment provides sufficient memory resources for your application.\nTSI_INIT_ERR_NO_TRACE_BUFFER No memory is available for the TSI trace buffer.\n\nAction: Check your system resources. Refer to Section 2.4 on page 44 to calculate system resources required by the TSI.\n\nTSI_INIT_ERR_SETRLIMIT_FAILED The TSI call to `setrlimit` failed. SUNOS, AIX, and SOLARIS only.\n\nAction: Check your system resources.\n\nTSI_INIT_ERR_TASK_VAR_FAILED The TSI failed to establish its internal task variables (VxWorks only).\n\nAction: If this error occurs consistently, contact Protogate for assistance.\n\nTSI_INIT_ERR_TSCCB_ALLOC_FAILED The TSI failed to allocate memory for its internal system control block.\n\nAction: Check your system resources. Refer to Section 2.4 on page 44 to calculate system resources required by the TSI. If this error occurs consistently, contact Protogate for assistance.\n\nFor additional error codes, refer to Appendix A.\n4.7 tListen\n\nThe tListen function waits for a connection request from a peer TSI application. It is similar to the tConnect function, except that the TSI waits for the peer TSI application to make a connection request (via tConnect). As with tConnect, the TSI searches the configuration file for a match of the connection name provided as the first parameter of this function call, then loads the parameters into memory. Once a connection request is received and validated, a connection is then made available to the application. Your application must issue another tListen call if it wishes to receive any additional connection requests.\n\nFor non-blocking I/O, tListen returns immediately as soon as it detects a potential blocking condition. Your application is not blocked while the TSI is waiting for a connection request. When the connection is made, the TSI calls one or both of the IOCH functions provided through the tInit and tListen calls. If no IOCH functions are provided, none is called. When using non-blocking I/O, the application can have up to TSI_MAX_LISTEN (defined in tsdefs.h file) outstanding “listens” for each connection definition in the application’s TSI configuration file. For example, at startup the application can call tListen multiple times to have several “listening connections” waiting for incoming connection requests.\n\nYour application uses the iConnID returned from this call for all other TSI calls (tRead, tWrite, and so on). If this connection is configured for non-blocking I/O, you must ensure that the connection is fully established before you call the tRead, tWrite, or tDisconnect functions.\n\n**Synopsis**\n\n```c\nint tListen (\n char *cTransportName, /* Transport name in TSI config file */\n int (*fUsrIOCH) (char *pUsrCB, int iConnID)); /* Optional IOCH for specific connection */\n```\nParameters\n\nchar *cTransportName A string of characters that specifies the name of the desired transport definition entry in the TSI binary configuration file. The associated configuration entry defines the characteristics of the connection to be completed when a connection request arrives.\n\nint (*fUsrIOCH) (char *pUsrCB, int iConnID) This field should contain the address of the I/O completion handler (IOCH) that TSI invokes immediately after it services an I/O condition for this connection. The TSI invokes the IOCH only if this connection is configured for non-blocking I/O. You must write the IOCH yourself. When an I/O condition occurs for this connection, the TSI invokes passes the pUsrCB value (that you provided with tInit) and the connection ID returned by this call. You can provide a different fUsrIOCH for each connection or use the same fUsrIOCH for all IDs. If your application does not wish the TSI to invoke your IOCH, this parameter should be NULL. The tInit function (Section 4.6) can also be used to define a general-purpose IOCH that is not restricted to one particular connection.\n\nReturns\n\nThe tListen function returns a non-negative connection ID or ERROR. The connection ID can have a value from zero to the maximum number of connections (MaxConns parameter, page 55) minus one. If the connection definition for the function parameter cTransportName specifies blocking I/O, a returned connection ID indicates that the connection has completed successfully. If the connection definition specifies non-blocking I/O and a connection ID is returned, the application must examine terrno and invoke tPoll with the TSI_POLL_GET_CONN_STATUS option to determine when the connection has successfully completed. If the connection has not completed upon return, terrno is set to TSI_EWOULDBLOCK.\nIf this function returns ERROR, the connection failed and tserrno contains one of the following error codes (listed alphabetically):\n\n**TSI_EWOULDBLOCK** The requested action could not be completed immediately. The TSI would have blocked this operation if your connection was using blocking I/O.\n\nAction: Use tPoll to check whether your request completed. You can program your application to be notified by one of the IOCH routines that you provided when you invoked the tInit, tConnect, or tListen function. Refer to Appendix B for information on managing TSI applications using non-blocking I/O.\n\n**TSI_LSTN_ERR_CLOSE_FAILED** The TSI failed to close its transport-dependent connection when it failed to complete the connection request.\n\nAction: If this error occurs consistently, contact Protogate for assistance.\n\n**TSI_LSTN_ERR_CONN_INIT_FAILED** The TSI failed to initialize a connection for the listener.\n\nAction: Check whether your connection name (first argument of tListen) is properly defined in the TSI configuration. Check your error log for additional error codes.\n\n**TSI_LSTN_ERR_INVALID_PROT** The value of the transport parameter in your configuration file is invalid.\n\nAction: Check whether configuration program, tsicfg, is at the same level as your library.\n\n**TSI_LSTN_ERR_INVALID_STATE** The TSI encountered an invalid state in its state processing machine.\n\nAction: If this error occurs consistently, contact Protogate for assistance.\nTSI_LSTN_ERR_LSTN_FAILED The TSI failed to establish a transport-dependent connection to the peer TSI application.\n\nAction: Review your TSI configuration file.\n\nTSI_LSTN_ERR_NO_LISTENERS The TSI failed to remove a connection from the internal listening queue.\n\nAction: If this error occurs consistently, contact Protogate for assistance.\n\nTSI_LSTN_ERR_NOT_SERVER A non-listener TSI connection tried to execute a transport-dependent listen.\n\nAction: If this error occurs consistently, contact Protogate for assistance.\n\nTSI_LSTN_ERR_QADD_FAILED The TSI failed to add a connection entry into its internal queue.\n\nAction: Severe error; if this error occurs consistently, contact Protogate for assistance.\n\nTSI_LSTN_ERR_QFULL The internal listening queue for this connection definition (cTransportName) is full and is not able to accept more listening requests.\n\nAction: Your application can post another listening request later, when one of the queued listeners completes a connection.\n\nTSI_LSTN_ERR_QINIT_FAILED The TSI failed to allocate an internal listening queue for the listener.\n\nAction: Severe error; terminate your application and try again.\n\nTSI_LSTN_ERR_SETOPT_FAILED This error is specific to the TCP/IP socket interface. The TSI failed in setting socket options on a newly accepted socket.\nAction: If this error occurs consistently, contact Protogate for assistance.\n\n**TSI_LSTN_ERR_SOCK_ALLOC_FAILED** The TSI failed to allocate a TCP/IP socket for the listener.\n\nAction: Review the TSI log for additional information.\n\n**TSI_LSTN_ERR_TINIT_FAILED** The TSI failed to initialize its services. This error can occur only if your application did not explicitly call the `tInit` function.\n\nAction: Check your binary configuration file. If the default binary configuration file (`tsicfg.bin`) was used by the TSI, verify its existence.\n\nFor additional error codes, refer to Appendix A.\n4.8 tPoll\n\nThe tPoll function queries information related to I/O operations, connection status, or system configuration status. The poll type parameter specifies the type of query; the most common uses are to acquire the status of a TSI connection and to poll for I/O completions (only for those connections using non-blocking I/O). Your application can call tPoll as often as necessary.\n\nSynopsis\n\n```c\nint tPoll ( \n int iConnID, /* Connection ID from tConnect/tListen */ \n int iPollType, /* Request type */ \n char **ppBuf, /* Poll-type dependent parameter */ \n int *piBufLen, /* Size of I/O buffer in bytes */ \n char *pStat ); /* Status or configuration buffer */\n```\n\nParameters\n\n- **iConnID** \nThe connection ID (returned from a tConnect or tListen function) that uniquely identifies an active connection serviced by the TSI. If a connection ID is not relevant to the iPollType parameter specified (TSI_POLL_GET_SYS_CFG, TSI_POLL_GET_CFG_LIST, TSI_POLL_TRACE_OFF, TSI_POLL_TRACE_ON, TSI_POLL_TRACE_WRITE), this parameter should be set to zero.\n\n- **iPollType** \nThis parameter specifies the type of poll request to the TSI. Valid poll types are:\n\n TSI_POLL_GET_CFG_LIST \n Request the TSI to get a list of all TSI connection definition names defined in the application's TSI configuration file. The list is returned through the ppBuf parameter in NULL-terminated string lists (see Section 4.1.3.3 on page 78). The number of connection definition names in the list is returned in the piBufLen parameter. The list does not contain the definition of the “main” section.\n**TSI_POLL_GET_CONN_STATUS** Request the TSI to get the current connection status of the connection ID, iConnID, given. The connection status is returned through the TSI_CONN_STAT structure (see Section 4.1.3.2 on page 78). The pointer to the TSI_CONN_STAT structure must be provided through the pStat parameter.\n\n**TSI_POLL_GET_SYS_CFG** Request the TSI to get the TSI system configuration. The system configuration is returned through the TSI_SYS_CFG structure (see Section 4.1.3.1 on page 76). The pointer to the TSI_SYS_CFG structure must be provided through the pStat parameter.\n\n**TSI_POLL_READ_CANCEL** Request the TSI to remove a read request from this connection's (iConnID parameter) input queue regardless of the completion status of the read request. If the content of the ppBuf (*ppBuf) parameter is NULL, the TSI removes the first entry in the input queue regardless of its completion status. If the content of ppBuf is not NULL, the TSI searches through its input queue for a matching address pointer. If it finds a match, it removes that request regardless of its completion status.\n\n**TSI_POLL_READ_COMPLETE** Request the TSI to remove the first read request from this connection's input queue if it is either complete, timed-out, or a read error occurred. The address and length of the buffer are returned through the ppBuf and piBufLen parameters. This request removes the first entry in the input queue only if the request is marked “read complete,” “read timed-out,” or “read error.” In all cases, the application is responsible for freeing the returned buffer.\n\n**TSI_POLL_TRACE_OFF** Request the TSI to disable tracing services. See Appendix C.\n\n**TSI_POLL_TRACE_ON** Request the TSI to enable tracing services. See Appendix C.\nTSI_POLL_TRACE_STORE Use this poll type to write your own information into the TSI trace buffer. Use the pStat parameter to indicate the area of memory to be copied to the trace buffer and the piBufLen parameter to indicate the length of the area to be copied. The length of your trace area must be less than or equal to the size of the trace buffer (TraceSize on page 55). Otherwise, your trace area will be truncated when copied into the TSI trace buffer.\n\nTSI_POLL_TRACE_WRITE Request the TSI to write the contents of the trace buffer to the trace file.\n\nTSI_POLL_WRITE_CANCEL Request the TSI to remove a write request from this connection’s (iConnID parameter) output queue regardless of the completion status of the write request. If the content of the ppBuf (*ppBuf) parameter is NULL, the TSI removes the first entry in the output queue regardless of its completion status. If the content of ppBuf is not NULL, the TSI searches through the output queue for a matching address pointer. If it finds a match, it removes that request regardless of its completion status.\n\nTSI_POLL_WRITE_COMPLETE Request the TSI to remove the first write request from this connection’s output queue if it is either complete or timed-out. The address and length of the buffer are returned through the ppBuf and piBufLen parameters. This request removes the first entry in the output queue only if the request is marked “write complete,” “write timed-out,” or “write error.” In any case, the application is responsible for freeing the returned buffer.\n\nchar **ppBuf This parameter specifies an address of a pointer to a buffer area. This parameter must not be NULL when the poll type is TSI_POLL_READ_COMPLETE, TSI_POLL_READ_CANCEL, TSI_POLL_WRITE_COMPLETE, or TSI_POLL_WRITE_CANCEL.\nint *piBufLen\n\nThis field is used to return the length of the buffer pointed to by the content of the ppBuf parameter (for I/O completes and cancels) or the number of entries in the configuration list for the TSI_POLL_GET_CFG_LIST option.\n\nchar *pStat\n\nThis field can be a pointer to a connection status or a system configuration structure. If the request is for the connection status, this field is the address of the user-supplied TSI_CONN_STAT structure (Section 4.1.3.2 on page 78). Otherwise, it points to the user-supplied TSI_SYS_CFG structure (Section 4.1.3.1 on page 76).\n\nReturns\n\nIf the tPoll function completes successfully, it returns OK. Otherwise it returns ERROR, and tserrno contains one of the following error codes (listed alphabetically):\n\n- TSI_POLL_ERR_BAD_PTR The ppBuf parameter supplied to tPoll was a NULL pointer. This error pertains only to the TSI_POLL_READ_COMPLETE, TSI_POLL_WRITE_COMPLETE, TSI_POLL_READ_CANCEL, and TSI_POLL_WRITE_CANCEL options.\n\n Action: Modify your application to supply the address of a pointer.\n\n- TSI_POLL_ERR_BUF_NOT_FOUND The TSI could not find the buffer pointed to by *ppBuf in its I/O queues. This error pertains only to the TSI_POLL_READ_CANCEL and TSI_POLL_WRITE_CANCEL options.\n\n Action: Severe error; if this error occurs consistently, contact Protogate for assistance.\n\n- TSI_POLL_ERR_GETLIST_FAILED The TSI failed to get a list of connection definition entries from the TSI configuration file.\n\n Action: Verify the configuration file.\n\n- TSI_POLL_ERR_INTERNAL An internal TSI error occurred.\nAction: Note the events leading to the error, obtain the TSI log, and contact Protogate for assistance.\n\n**TSI_POLL_ERR_INVALID_ID** Your connection is no longer valid.\n\nAction: Review your error log, terminate your application, and try again.\n\n**TSI_POLL_ERR_INVALID_IOQ** The TSI could not access the connection’s I/O queues. This error pertains only to the TSI_POLL_READ_COMPLETE, TSI_POLL_WRITE_COMPLETE, TSI_POLL_READ_CANCEL, and TSI_POLL_WRITE_CANCEL options.\n\nAction: Severe error; if this error occurs consistently, contact Protogate for assistance.\n\n**TSI_POLL_ERR_INVALID_REQ_TYPE** The iPollType parameter did not contain a valid value.\n\nAction: Review your application to ensure that a valid poll option is used.\n\n**TSI_POLL_ERR_NEVER_INIT** The TSI was never initialized.\n\nAction: Revise your program and try again.\n\n**TSI_POLL_ERR_OVERFLOW** The buffer returned in the ppBuf parameter was too small to handle the incoming TSI packet. The overflow portion of the incoming packet was discarded. Note that this buffer must still be freed by the application. This error pertains only to the TSI_POLL_READ_COMPLETE option.\n\nAction: Increase the buffer size supplied to tRead up to the maximum defined for the connection.\n\n**TSI_POLL_ERR_QEMPTY** The pertinent I/O queue is empty. This error pertains only to the TSI_POLL_READ_COMPLETE,\nTSI POLL_WRITE_COMPLETE, TSI POLL_READ_CANCEL, and TSI POLL_WRITECANCEL options.\n\nAction: This can be a normal condition if the application is attempting to empty the corresponding queue.\n\nTSI POLL_ERR_QREM_FAILED The TSI failed to remove a buffer from a non-empty I/O queue. This error pertains only to the non-specific (no buffer pointer was supplied) TSI POLL_READ_CANCEL and TSI POLL_WRITE_CANCEL options.\n\nAction: Severe error; if this error occurs consistently, contact Protogate for assistance.\n\nTSI POLL_ERR_READ_NOT_COMPLETE The head entry in the TSI read queue is still pending (but has not timed out or incurred an error in processing). This error code pertains only to the TSI POLL_READ_COMPLETE option.\n\nAction: This is a normal condition when polling for I/O completions.\n\nTSI POLL_ERR_READ_TIMEOUT The head entry in the TSI read queue has timed out. Note that the buffer returned in the ppBuf parameter must still be freed by the application. This error code pertains only to the TSI POLL_READ_COMPLETE option.\n\nAction: Consider raising the timeout parameter value in the connection definition of the TSI configuration file.\n\nTSI POLL_ERR_SOCK_CLOSED A fatal error occurred on this buffer's attempted I/O operation. The connection between the client application and Freeway has been closed.\n\nAction: Cancel all outstanding read and write requests, and free the buffers. Close the connection. After a successful close, another connection can be attempted. Examine the error logs for details of the failure.\nTSI_POLL_ERR_UNBIND The connection between the client application and Freeway has been closed. The system has performed “Unbind” processing. The connection was closed either because of a “Force Unbind” received from the peer entity (Freeway or client), or because of a failure with the I/O connection.\n\nAction: Cancel all outstanding read/write requests and free the buffers. Close the connection. After a successful close, another connection can be attempted. Examine the message logs on the peer system (if the error occurred in the client application, examine the Freeway log).\n\nTSI_POLL_ERR_WRITE_NOT_COMPLETE The head entry in the TSI write queue is still pending (but has not timed out or incurred an error in processing). This error code pertains only to the TSI_POLL_WRITE_COMPLETE option.\n\nAction: This is a normal condition when polling for I/O completions.\n\nTSI_POLL_ERR_WRITE_TIMEOUT The head entry in the TSI write queue has timed out. Note that the buffer returned in the ppBuf parameter must still be freed by the application. This error code pertains only to the TSI_POLL_WRITE_COMPLETE option.\n\nAction: Consider raising the timeout parameter value in the connection definition of the TSI configuration file.\n\nFor additional error codes, refer to Appendix A.\n4.9 tPost\n\nThe tPost function operates only in the VxWorks environment where the basic non-blocking I/O system services are not provided. It signals the TSI to begin processing I/O requests queued by your application.\n\nCurrently, tPost implements a controlled task switch environment for VxWorks through the use of binary semaphore mechanisms. Your application must call this function as the last operation before it relinquishes task control to the operating system (for example, sleeping or taking semaphores). Your application must take special consideration to operate in a VxWorks environment. Refer to Appendix B for designing and implementing server-resident applications under a VxWorks environment.\n\nSynopsis\n\n```c\nint tPost ( void );\n```\n\nParameters\n\nNone\n\nReturns\n\nIf the tPost function completes successfully, it returns OK. Otherwise it returns ERROR, and tserrno contains one of the following error codes (listed alphabetically):\n\n- **TSI_POST_ERR_CLIENT_INVALID_SEM** The TSI call to the VxWorks semGive function failed because the semaphore ID is not valid.\n \n Action: Internal error. If this error occurs consistently, contact Protogate for assistance.\n\n- **TSI_POST_ERR_NEVER_INIT** The TSI was never initialized (tInit).\n \n Action: Correct your program and try again.\nTSI_POST_ERR_SERVER_INVALID_SEM The TSI call to the VxWorks semGive function failed because the semaphore ID is not valid.\n\nAction: Internal error. If this error occurs consistently, contact Protogate for assistance.\n\nFor additional error codes, refer to Appendix A.\n4.10 tRead\n\nThe tRead function requests the TSI to receive data from the peer TSI application over the specified connection ID.\n\nThe use of tRead varies slightly when using non-blocking I/O as opposed to blocking I/O. If the read is for a connection using non-blocking I/O, note the following:\n\n- If tRead returns ERROR and t_errno is set to TSI_READ_ERR_QFULL, the input queue for this connection is full and cannot accept any more requests at this time.\n\n- If tRead returns ERROR and t_errno is set to TSI_EWOULDBLOCK, the read could not be completed immediately, but was queued to the input queue. Upon completion, the read can be retrieved from the queue by calling tPoll with the TSI_POLL_READ_COMPLETE option.\n\nSynopsis\n\n```c\nint tRead ( \n int iConnID, /* Connection ID from tConnect/tListen */\n char **ppBuf, /* Buffer to receive data */\n int iBufLen ); /* Maximum bytes to be returned */\n```\n\nParameters\n\n- int iConnID The connection ID uniquely identifies an active connection serviced by the TSI. This ID is returned from the tConnect or tListen function call.\n\n- char **ppBuf This field contains the address of a pointer to a read buffer. The buffer can be allocated using the tBufAlloc function or a similar C function. However, if the buffer is allocated by a function other than tBufAlloc, your application must provide sufficient header space for the TSI control information (usOverhead field on page 77). If its content is NULL, TSI allocates a buffer for your application.\n\nThis parameter must not be NULL, but it can be the address of a NULL pointer (*ppBuf = NULL), which instructs the TSI to allocate a TSI read buffer for the\napplication. Upon return, the TSI fills in this pointer with the address of the allocated TSI buffer. If you let TSI allocate the read buffer, your application is still responsible for releasing that buffer when it no longer needs it, using tBufFree.\n\nint iBufLen This field specifies the maximum number of bytes to be read. This value must be greater than zero and less than the maximum buffer size configured (iMaxBufSize, page 77, as reported by the tPoll call with the TSI_POLL_GET_SYS_CFG option). The TSI is a message-based transport service, meaning that data is not transferred as a continuous stream of bytes; the data is broken up into discrete packets (messages) that also contain TSI control information. When an application requests a read, it is returned in the next incoming packet. Because the application does not know the data size of the incoming packet, it is suggested that the application always request to read the maximum buffer size allowed and supply an appropriate sized buffer (or let TSI allocate the buffer). Incoming packets are handled as follows:\n\n- If the data length of the next incoming packet is less than or equal to iBufLen, tRead returns the length of the incoming packet.\n\n- If the data length of the next incoming packet is greater than iBufLen, tRead returns ERROR and tserrno is set to TSI_READ_ERR_OVERFLOW. The buffer is truncated to the number of bytes requested, and the remaining data is discarded.\n\nReturns\n\nThe tRead function returns the number of bytes transferred if the TSI successfully completes the I/O request. For both blocking and non-blocking I/O connections, a positive return value signifies a successful completion of the read. Otherwise, the return code is ERROR, and tserrno contains one of the following error codes (listed alphabetically):\nTSI_EWOULDBLOCK The requested action could not be completed immediately. The TSI would have blocked this operation if your connection was using blocking I/O.\n\n Action: Use tPoll to check whether your request completed. You can program your application to be notified by one of the IOCH routines that you provided when you invoked the tInit, tConnect, or tListen function. Refer to Appendix B for information on managing TSI applications using non-blocking I/O.\n\nTSI_READ_ERR_INTERNAL A TSI internal error was detected during read processing. The TSI log will indicate the specific error.\n\n Action: Obtain the TSI error log, and contact Protagate for assistance.\n\nTSI_READ_ERR_INVALID_BUF This function was invoked with a NULL ppBuf pointer.\n\n Action: Correct your application and try again.\n\nTSI_READ_ERR_INVALID_ID Your connection ID is no longer valid.\n\n Action: Review your application and try again.\n\nTSI_READ_ERR_INVALID_LENGTH Your requested read length (iBufLen) must be greater than zero and less than or equal to the maximum buffer length allowed by the TSI.\n\n Action: Use tPoll to obtain the maximum buffer size allowed by the TSI (iMaxBufSize). Review your program and try again.\n\nTSI_READ_ERR_INVALID_STATE This connection is not in a proper state to accept a read request.\n\n Action: Review your program and try again.\nTSI_READ_ERR_LIMIT_EXCEEDED This connection has a large number of I/O errors that exceeded the maximum number of errors allowed.\n\nAction: Consider increasing the maximum I/O errors parameter in the connection definition entry. Review your operating environments.\n\nTSI_READ_ERR_NEVER_INIT The TSI was never initialized. Your application must initialize the TSI (tInit) before calls to other TSI functions (except tConnect and tListen) are made.\n\nAction: Review your application.\n\nTSI_READ_ERR_NO_BUFS Your application requested that the TSI allocate a buffer, but the allocation failed.\n\nAction: Review your program and make sure you free unused buffers. Also, check to see if you configured enough buffers for your application.\n\nTSI_READ_ERR_OVERFLOW The TSI encountered an overflow of data in your read request. The read length specified was smaller than the size of the incoming TSI packet. See the discussion under the Description heading.\n\nAction: Increase the buffer size supplied to tRead up to the maximum defined for the connection.\n\nTSI_READ_ERR_QADD_FAILED The TSI failed to add your request to its internal I/O queues for this connection.\n\nAction: Severe error; terminate your application and try again.\n\nTSI_READ_ERR_QFULL The TSI cannot accept more read requests because its input queue is full.\n\nAction: Your application must remove complete or timed-out read requests, using the tPoll call, before it can request more reads. Review your program and handle this error accordingly.\nTSI_READ_ERR_READ_TIMEOUT Your request was not completed in a timely manner.\n\nAction: Consider increasing the timeout value in the configuration parameters for this connection.\n\nTSI_READ_ERR_SELECT The TSI received an error from a system select call during a read attempt using blocking I/O.\n\nAction: Retry the operation. If the error persists, review your application.\n\nTSI_READ_ERR_SOCK_CLOSED A system read attempt failed, and TSI has closed the connection.\n\nAction: Cancel all outstanding read and write requests, and free the buffers. Close the connection. After a successful close, another connection can be attempted. Examine the log files for abnormal conditions prior to the read failure.\n\nTSI_READ_ERR_UNBIND This connection between Freeway and the client application has been closed. The system has performed \"Unbind\" processing. The connection was closed either because of a \"Force Unbind\" received from the peer entity (Freeway or client), or because of a failure with the I/O connection.\n\nAction: Cancel all outstanding read/write requests and free the buffers. Close the connection. After a successful close, another connection can be attempted. Examine the log files on the peer system (if the error occurred in the client application, examine the Freeway log).\n\nFor additional error codes, refer to Appendix A.\n4.11 tSyncSelect\n\nThe tSyncSelect function queries a set of connection IDs for a read data available condition. This feature is available only for clients in a Freeway server environment (it is not supported in an embedded ICP environment) using blocking I/O. The client application can query a connection(s) for read data, and if available, perform the read operation without blocking. This operation does not block; it interrogates the system for read data available and immediately returns this status to the user.\n\nThe user builds a connection ID array (connIDArray) containing the list of connections for which read availability is requested. The number of connections can be from 1 to the defined maximum number of connections (see the TSI MaxConns parameter on page 55). Connection IDs must begin at position 0 in the array (first position in the array), and be packed (no non-used positions). The contents of this array are not modified by the interface. The number of connection IDs packed in this array is passed in iNbrConID. In addition, a result array is passed which will contain the returned read availability status of the connections in the corresponding array position of the connection ID array. A connection’s availability status is either TRUE (data available) or FALSE (data not available).\n\nSynopsis\n\n```c\nint tSyncSelect ( \n int iNbrConnID, /* # of connection ids in connIDArray */ \n int connIDArray[], /* packed array of connection ids for requested read data status */ \n int readStatArray[]); /* array containing read data status for connections in connIDArray */\n```\n\nParameters\n\n- **int iNbrConnID** The number of connection IDs to be queried in the following connection ID array. If a value of 0 is passed (no connection IDs to be queried), the function returns zero (0).\nint connIDArray[] An array containing the connection IDs whose read availability status is requested. The connection IDs are those returned from tConnect. Connection ids must begin at position 0 (the first array element), and be packed (no non-used positions). These values are not modified by the call.\n\nint readStatArray[] An array passed to the interface for the returned TRUE/FALSE read availability status for connections in the corresponding positions of the connection ID array (connIDArray). This array is modified by the interface. If an error occurs in the call, the contents of this array are indeterminable; all elements should be ignored.\n\nReturns\n\nIf the tSyncSelect function completes successfully, it returns the number of connections in the connection ID array that have read data available (if 3 of 7 connections in the array have read data available, a value of 3 is returned). If no connections have data available, 0 is returned.\n\nSuccessful completion also returns the readStatArray with a TRUE/FALSE value in each position corresponding to the connection ID in the connection ID array. TRUE means that connection has data available; FALSE means data is not currently available. If the function returns a 0 or ERROR, values in this array are indeterminable; they should be ignored. If this function is successful, it modifies iNbrConnID positions in this array.\n\nFor any error condition, the tSyncSelect return code is ERROR, and errno contains one of the following error codes (listed alphabetically):\n\nTSI_SYNCSELECT_ERR_INVALID_STATE A connection(s) in the connection ID array (connIDArray) is not in the proper state to accept this request. con-\nConnections must be “opened” (in the “ready” state) before this operation can be performed.\n\nAction: Ensure all connections in the connection ID array have successfully opened.\n\nTSI_SYNCSELECT_ERR_SELECT_ERROR An error was returned from the system select function.\n\nAction: Review the TSI log file for the specific error, and take corrective action.\n\nExample\n\nOne connection is open, tConnect returned with a connection ID of 4.\n\n```c\nconnIDArray[0] = 4;\nif ( (nbrReads = tSyncSelect( 1, connIDArray, readStatArray ) ) == ERROR )\n{\n error processing\n}\nif ( nbrReads ) /∗ with only one read in array, we need not look further */\n{\n if ( readStatArray[0] == TRUE )\n {\n /∗ process read available for connection connIDArray[0] – tRead */\n }\n}\n```\n\nWith multiple connections in array, go through readStatArray iNbrConnID times or until nbrReads of TRUE are found.\n4.12 tTerm\n\nThe tTerm function closes all connections and frees all TSI-related system resources. Under normal conditions your application should call tTerm to close all active connections before it exits to the operating system. You should also make an effort to call tTerm when your application ends abnormally.\n\nThe tTerm function can be invoked at any time during the life of your application. To use the TSI again, you must call tInit to re-establish the TSI operating environment. It is not recommended that you call tTerm too often in your application because of the timing cost associated with it. However, in some applications this capability might be essential if your system and network resources are scarce and your application is not time-critical. If you call tTerm while there are active connections, the TSI issues a forced tDisconnect on the active connections before it brings down its service structure. Issuing tTerm while active connections exist should be the last option.\n\n----\n\n**Note**\n\nThe successful writing of client trace files to the client file system requires successful completion of the tTerm function. When the client application abnormally terminates, TSI trace files are not written.\n\n---\n\n**Synopsis**\n\n```c\nint tTerm ( void );\n```\n\n**Parameters**\n\nNone\nReturns\n\nIf this function completes successfully, it returns OK. Otherwise it returns ERROR, and `tserrno` contains one of the following error codes (listed alphabetically):\n\n- **TSI_TERM_ERR_ACT_REM_FAILED** The TSI failed to terminate its internal active connection queue.\n \n Action: Severe error; terminate your application and try again.\n\n- **TSI_TERM_ERR_ACT_TERM_FAILED** The TSI failed to terminate its internal active connection queue.\n \n Action: Severe error; terminate your application and try again.\n\n- **TSI_TERM_ERR_BUF_FREE_FAILED** The TSI failed in removing buffers used by the application.\n \n Action: Severe error; terminate your application and try again.\n\n- **TSI_TERM_ERR_BUFM_TERM_FAILED** The TSI failed to terminate buffer management services.\n \n Action: Review your TSI configuration services and TSI error log.\n\n- **TSI_TERM_ERR_DISC_FAILED** The TSI failed to disconnect an active connection.\n \n Action: Severe error; terminate your application and try again.\n\n- **TSI_TERM_ERR_LOG_END_FAILED** The TSI failed to terminate its internal logging and tracing facility.\n \n Action: Check your logging-related and tracing-related parameters in the currently used TSI configuration file.\n\n- **TSI_TERM_ERR_NEVER_INIT** The TSI was never initialized with a call to tinit.\nAction: Review your program's logic, and try again.\n\n**TSI_TERM_ERR_RES_FREE_FAILED** The TSI failed to free connection-related resources.\n\nAction: Review the TSI connection log, terminate your application and try again.\n\nFor additional error codes, refer to Appendix A.\n4.13 tWrite\n\nThe tWrite function requests the TSI to send data to a peer TSI application over the specified connection ID.\n\nFor both blocking and non-blocking I/O connections, a positive return value signifies a successful completion of the write. If the write is for a connection using non-blocking I/O, note the following:\n\n- If tWrite returns ERROR and tserrno is set to TSI_WRIT_ERR_QFULL, the output queue for this connection is full and cannot accept any more requests at this time.\n\n- If tWrite returns ERROR and tserrno is set to TSI_EWOULDBLOCK, the write could not be completed immediately, but was queued to the output queue. Upon completion, the write can be retrieved from the queue by calling tPoll with the TSI_POLL_WRITE_COMPLETE option.\n\nSynopsis\n\n```c\nint tWrite( int iConnID, /* Connection ID from tConnect/tListen */\n char *pBuf, /* Source buffer for transfer */\n int iBufLen, /* Number of bytes to transfer */\n int iWritePriority ); /* Normal or expedite queueing */\n```\n\nParameters\n\n**int iConnID** This field uniquely identifies an active connection serviced by the TSI. This ID is returned from a tConnect or tListen function call.\n\n**char *pBuf** This field contains the address of the write buffer to be sent to the peer TSI application. This parameter must not be NULL. The buffer can be allocated using the tBufAlloc function or a similar C function. However, if the buffer is allocated by a function other than tBufAlloc, your application must provide sufficient header space for the TSI control information (usOverhead field on page 77).\nCaution\n\nNormally, if the client application allocates the write buffer using \\texttt{tBufAlloc}, it must release the buffer using \\texttt{tBufFree} when the write request completes. A server-resident application is an exception (see Section 2.3.7 on page 43).\n\n\\begin{verbatim}\nint iBufLen This field specifies the number of bytes to be sent. This value must be greater than zero and less than the maximum buffer size configured (\\texttt{iMaxBufSize}, page 77, as reported by the \\texttt{tPoll} call with the \\texttt{TSI_POLL_GET_SYS_CFG} option).\n\nint iWritePriority This field specifies the priority of the write operation. Your application can use this field to expedite a request to the peer TSI application. The default type is a normal write operation. Note that this field has no meaning for a connection using blocking I/O, as only one write can be pending at a time. Valid types are:\n\n\\begin{itemize}\n \\item \\texttt{TSI_WRITE_EXPEDITE} If this type is used, your current request is inserted before any output requests whose actual output operation has not started and after any output request that has already started or that was issued with \\texttt{TSI_WRITE_EXPEDITE}. This exercises the priority queue concept.\n \\item \\texttt{TSI_WRITE_NORMAL} If this type is used, your output request is added to the end of the connection internal output queue. This exercises the FIFO concept of queue.\n\\end{itemize}\n\nReturns\n\nThe \\texttt{tWrite} function returns the transfer count if the TSI successfully completes the I/O. Otherwise, the return code is \\texttt{ERROR}, and \\texttt{tserrno} contains one of the following error codes (listed alphabetically):\n\\end{verbatim}\nTSI_EWOULD_BLOCK The requested action could not be completed immediately. The TSI would have blocked this operation if your connection was using blocking I/O.\n\nAction: Use tPoll to check whether your request completed. You can program your application to be notified by one of the IOCH routines that you provided when you invoked the tInit, tConnect, or tListen function. Refer to Appendix B for information on managing TSI applications using non-blocking I/O.\n\nTSI_WRIT_ERR_INVALID_BUF Your application invoked this function with a NULL pBuf pointer.\n\nAction: Correct your application and try again.\n\nTSI_WRIT_ERR_INTERNAL A TSI internal error was detected during write processing. The TSI log will indicate the specific error.\n\nAction: Have the TSI error log available, and contact Protogate.\n\nTSI_WRIT_ERR_INVALID_ID Your connection ID is no longer valid.\n\nAction: Review your log, terminate your program, and try again.\n\nTSI_WRIT_ERR_INVALID_LENGTH The buffer length (iBufLen) must be greater than zero and less than the maximum buffer length allowed by the TSI.\n\nAction: Use tPoll to obtain the maximum buffer length allowed by the TSI (iMaxBufSize). Correct your application and try again.\n\nTSI_WRIT_ERR_INVALID_STATE This connection is not in a proper state to accept a write request.\n\nAction: Review your program and try again.\nTSI_WRIT_ERR_INVALID_WRITE_TYPE \n\n*tWrite* allows either TSI_WRITE_NORMAL or TSI_WRITE_EXP.\n\nAction: Review your program's logic, and try again.\n\nTSI_WRIT_ERR_LIMIT_EXCEEDED \n\nThis connection has a large number of I/O errors that exceeded the maximum number of errors allowed.\n\nAction: Consider increase the maximum I/O errors parameter in the connection definition entry. Review your operating environments.\n\nTSI_WRIT_ERR_NEVER_INIT \n\nThe TSI was never initialized. Your application must initialize the TSI (*tInit*) before it can use it.\n\nAction: Review your application.\n\nTSI_WRIT_ERR_QADD_FAILED \n\nThe TSI failed to add your write request to its internal I/O queues for this connection.\n\nAction: Severe error; terminate your application and try again.\n\nTSI_WRIT_ERR_QFULL \n\nThe TSI cannot accept more write requests because its output queue is full.\n\nAction: Your application must remove complete or timed-out write requests, using the *tPoll* call, before it can request more writes. Review your program and handle this error accordingly.\n\nTSI_WRIT_ERR_SELECT \n\nThe TSI received an error from a system select call during a write attempt using blocking I/O.\n\nAction: Retry the operation. If the error persists, review your application.\n\nTSI_WRIT_ERR_SOCK_CLOSED \n\nA system write attempt failed, and TSI has closed the connection.\nAction: Cancel all outstanding read and write requests, and free the buffers. Close the connection. After a successful close, another connection can be attempted. Examine the log files for abnormal conditions prior to the write failure.\n\n**TSI_WRIT_ERR_UNBIND** This connection between Freeway and the client application has been closed. The system has performed “Unbind” processing. The connection was closed either because of a “Force Unbind” received from the peer entity (Freeway or client), or because of a failure with the I/O connection.\n\nAction: Cancel all outstanding read/write requests and free the buffers. Close the connection. After a successful close, another connection can be attempted. Examine the log files on the peer system (if the error occurred in the client application, examine the Freeway log).\n\n**TSI_WRIT_ERR_WRITE_TIMEOUT** Your request was not completed in timely manner.\n\nAction: Increase the timeout value in the configuration for this connection.\n\nFor additional error codes, refer to Appendix A.\nAppendix A\n\nTSI Common Error Codes\n\nThis chapter describes the internal and command-specific TSI error codes.\n\nNote\nWhile developing your TSI application, if a particular error occurs consistently, contact Protogate for further assistance.\n\nA.1 Internal Error Codes\n\nTo assist you in debugging your application, the following codes (listed alphabetically) describe internal error conditions of TSI services. These codes are returned in the global variable tserrno.\n\nTSI_CINIT_ERR_CFG_LOAD_FAILED TSI failed to load the configuration entry from the TSI configuration file.\n\nAction: Ensure that your tsicfg program and your TSI library is up-to-date. Make sure your application uses a correct connection entry name through the first parameter of the tConnect or tListen function call. Note that the connection entry name is case-sensitive.\n\nTSI_CINIT_ERR_DEQ_FAILED TSI failed to dequeue its internal active connection entry.\n\nAction: If this error occurs consistently, it is considered a severe error; contact Protogate for further assistance.\nTSI_CINIT_ERR_GET_ENTRY_FAILED TSI failed to add the newly created connection entry to its internal connection queue.\n\nAction: Severe error. Terminate your application and try again.\n\nTSI_CINIT_ERR_QFULL TSI failed to add a new connection entry to its internal connection queue.\n\nAction: Consider increasing the number of connections (MaxConns parameter) through the TSI configuration file. If this error occurs consistently even though the maximum number of connections is adequately defined, contact Protogate for further assistance.\n\nTSI_CINIT_ERR_RESA_FAILED TSI failed to allocate system resources for this newly created connection.\n\nAction: Review more error messages to pinpoint the problems. Recalculate your system resource requirements and adjust your configuration file accordingly.\n\nTSI_CLNT_ERR_EVT_PROC_FAILED TSI failed to complete its internal event processing routine.\n\nAction: If this error occurs consistently, contact Protogate for further assistance. VxWorks only.\n\nTSI_CLNT_ERR_TASK_VAR_FAILED TSI failed to add task variables to the VxWorks system. Severe error.\n\nAction: Contact Protogate for further assistance. VxWorks only.\n\nTSI_EVTG_ERR_ILL_CMD_TYPE A TSI command packet with an invalid command field was processed. Severe error.\n\nAction: Terminate your application and try again.\nTSI_INTERN_ERR_01 A TSI error occurred during write processing without being correctly identified. TSI_WRIT_ERR_INTERNAL is returned to the application.\n\nAction: If this error occurs consistently, contact Protogate for further assistance.\n\nTSI_INTERN_ERR_02 A TSI error occurred during read processing without being correctly identified. TSI_READ_ERR_INTERNAL is returned to the application.\n\nAction: If this error occurs consistently, contact Protogate for further assistance.\n\nTSI_INTERN_ERR_03 A TSI_INTERN_ERR_01 or TSI_INTERN_ERR_02 error has been recognized in returning a buffer from a poll request for read/write completions. TSI_POLL_ERR_INTERNAL is returned to the application.\n\nAction: If this error occurs consistently, contact Protogate for further assistance.\n\nTSI_INT_ERR_SELECT_FAILED TSI failed to perform a select on its active socket file descriptors. Severe error.\n\nAction: Terminate your application and try again. Non-blocking I/O with socket interface only.\n\nTSI_INTR_ERR_CLIENT_SPAWN_FAILED TSI failed to spawn its internal IOClient task. Severe error.\n\nAction: Ensure that your VxWorks system resources are properly configured. Make sure that your linkage completes successfully. VxWorks only.\n\nTSI_INTR_ERR_SEM_FAILED TSI failed to create a binary semaphore for its internal usage. Severe error.\n\nAction: Ensure that your VxWorks system resource is properly configured. VxWorks only.\nTSI_INTR_ERR_SERVER_SPAWN_FAILED TSI failed to spawn its internal IOServer task. Severe error.\n\nAction: Ensure that your VxWorks system resources are properly configured. Make sure that your linkage completes successfully. VxWorks only.\n\nTSI_INTR_ERR_SIG_ERR TSI failed to install its SIGIO signal to UNIX or a UNIX-like system. Severe error.\n\nAction: Make sure your TSI application does not use SIGIO signal. UNIX or UNIX-like only.\n\nTSI_INTR_ERR_SOCKET_SPAWN_FAILED TSI failed to spawn its internal IOSocket task. Severe error.\n\nAction: Ensure that your VxWorks system resources are properly configured. Make sure that your linkage completes successfully. VxWorks only.\n\nTSI_IO_ERR_INVALID_EXEC_STATE The TSI has gone through an invalid state transition. Severe error.\n\nAction: Make sure that your network is functioning properly. Terminate your application and try again.\n\nTSI_LOGI_ERR_LOG_OPEN_FAILED TSI failed to open its internal error log.\n\nAction: Check access authority for the current directory.\n\nTSI_LOGI_ERR_TRC_OPEN_FAILED TSI failed to open the trace file for input.\n\nAction: Check access authority for the current directory.\n\nTSI_MEMI_ERR_CALLOC_FAILED TSI failed to obtained adequate memory resources to operate.\nA: TSI Common Error Codes\n\nTSI_MEMI_ERR_NEVER_INIT TSI is not initialized correctly.\n\nAction: Review your program logic and try again. VxWorks with shared-memory package only.\n\nTSI_RECV_PACK_ERR_QADD_FAILED The TSI failed to queue a read for an incoming control packet. Severe error.\n\nAction: Ensure that your TSI configuration file defines an adequate queue size.\n\nTSI_RECV_PACK_ERR_NO_BUFS The TSI failed to obtain a buffer for an internal control packet.\n\nAction: Ensure that your TSI configuration file includes an adequate number of buffers.\n\nTSI_RESA_ERR_BUFIO_FAILED TSI failed to obtain two internal IO buffers for the newly created connection. The connection request will fail.\n\nAction: Ensure that your TSI configuration file includes adequate buffer configuration.\n\nTSI_RESA_ERR_INVALID_PROT TSI failed to recognize the protocol specified in the configuration file.\n\nAction: Ensure that your tsicfg and your TSI library are up-to-date.\nTSI_RESA_ERR_QIO_FAILED TSI failed to create its internal IO queue for the newly requested connection.\n\nAction: Recalculate your system resource requirements. If needed, re-configure your TSI to match your limited system resources and try again.\n\nTSI_SEND_PACK_ERR_NO_BUFS The TSI failed to obtain a buffer for an internal control packet.\n\nAction: Ensure that your TSI configuration file includes an adequate number of buffers.\n\nTSI_SEND_PACK_ERR_QADD_FAILED The TSI failed to queue a write for an outgoing control packet. Severe error.\n\nAction: Ensure that your TSI configuration file defines an adequate queue size.\n\nTSI_SHM_ERR_CTL_PROC_QTERM_FAIL An error occurred while terminating the TSI shared-memory queues.\n\nAction: If this error occurs consistently, contact Protogate for assistance.\n\nTSI_SHM_ERR_CTRL_PROC_FAILED An error occurred while the TSI was processing a shared-memory control packet.\n\nAction: If this error occurs consistently, contact Protogate for assistance.\n\nTSI_SHM_ERR_INVALID_STATUS An invalid status was reached while executing a shared-memory open. Severe error.\n\nAction: If this error occurs consistently, contact Protogate for assistance.\n\nTSI_SHM_ERR_KILL_SIG1_FAILED The TSI failed to send SIGUSR1 to process a shared-memory open.\nAction: Make sure that your TSI application does not use SIGUSR1 on VxWorks. Terminate your application and try again. If this error occurs consistently, contact Protogate for assistance.\n\nTSI_SHM_ERR_NOT_OPEN The TSI attempted to close a shared-memory transport that was not open.\n\nAction: Review your application logic. Terminate your application and try again.\n\nTSI_SHM_ERR_NO_BUFS The TSI failed to obtain a buffer for an internal control packet.\n\nAction: Ensure that your TSI configuration file includes an adequate number of buffers.\n\nTSI_SHM_ERR_NO_RESOURCE The TSI failed to initialize the shared-memory queues for a connection.\n\nAction: Your application probably has inadequate memory resources; check the TSI configuration.\n\nTSI_SHM_ERR_OPEN_PROC_NO_BUFS The TSI failed to obtain a buffer for an internal control packet.\n\nAction: Ensure that your TSI configuration file includes an adequate number of buffers.\n\nTSI_SHM_ERR_OPEN_PROC_NO_LSTN A shared-memory open request was rejected. No outstanding listens were posted to the requested Transport Name.\n\nAction: Ensure that your TSI configuration file includes an adequate number of buffers.\n\nTSI_SHM_ERR_PIPE_OPENFAILED The TSI failed to open its peer's shared-memory open request pipe.\nAction: Ensure that the client connection definition's server parameter matches the server main definition's servername parameter in the corresponding TSI configuration files.\n\nTSI_SHM_ERR_PIPE_READ_FAILED A TSI shared-memory listening connection incurred an error attempting to read from the shared-memory request pipe.\n\nAction: Severe error. Terminate your application and try again.\n\nTSI_SHM_ERR_PIPE_SEL_FAILED A TSI shared-memory listening connection incurred an error attempting to perform a select on the shared-memory request pipe.\n\nAction: Severe error. Terminate your application and try again.\n\nTSI_SHM_ERR_PIPE_WRITE_FAILED A TSI shared-memory client connection incurred an error attempting to write an open request to the shared-memory request pipe.\n\nAction: Severe error. Terminate your application and try again.\n\nTSI_SHM_ERR_QREM_AT_CTLBUF_FAIL The TSI incurred an error attempting to remove a TSI control packet from the connection's queue.\n\nAction: Severe error. Terminate your application and try again.\n\nTSI_SOCK_ERR_ACCEPT_ERR An accept on a TSI listening socket failed.\n\nAction: Check system resources to ensure that the system limit for open file descriptors has not been reached.\n\nTSI_SOCK_ERR_ALREADY_CLOSED The TSI attempted to close a socket that was not open.\n\nAction: Internal logic error. Contact Protogate to report problem.\n\nTSI_SOCK_ERR_CLOSE_ERR The TSI incurred an error while closing an open socket.\nA: TSI Common Error Codes\n\nAction: Terminate your application and try again.\n\nTSI_SOCK_ERR_CONNECT_ERR The TSI failed to connect a client socket.\n\nAction: Severe error. Terminate your application and try again.\n\nTSI_SOCK_ERR_GET_HNAME_FAILED The TSI failed to convert the server host\nname to an IP address.\n\nAction: Ensure that the TSI configuration file contains a valid host name for the\nserverName parameter.\n\nTSI_SOCK_ERR_INVALID_IOQ_STATUS The IO status field of a TSI socket packet\ncontains an invalid status. Severe error.\n\nAction: Terminate your application and try again.\n\nTSI_SOCK_ERR_INVALID_RTN_VALUE The TSI generated an invalid internal value.\n\nAction: If this error occurs consistently, contact Protogate for further assistance.\n\nTSI_SOCK_ERR_NO_SOCKET The TSI did not have a valid socket file descriptor to\nperform a socket open or listen.\n\nAction: Terminate your application and try again.\n\nTSI_SOCK_ERR_READ_FAILED The TSI encountered an error performing a read\nfrom a socket.\n\nAction: Check the TSI log file just prior to this error for more detailed informa-\ntion.\n\nTSI_SOCK_ERR_SELECT_ERR The TSI encountered an error performing a select on\na socket.\n\nAction: Terminate your application and try again.\nTSI_SOCK_ERR_SEM_CREATE_FAILED TSI failed to create an internal semaphore for its internal socket task.\n\nAction: Recalculate your system resource requirements. If needed, reconfigure your TSI configuration file. VxWorks only.\n\nTSI_SOCK_ERR_SOCKET_CLOSED A socket that the TSI was attempting to perform IO upon closed.\n\nAction: Check the peer software and attempt to discover why the peer socket closed.\n\nTSI_SOCK_ERR_TASK_VAR_FAILED TSI failed to add task variables to the VxWorks system. Severe error.\n\nAction: Contact Protogate for further assistance. VxWorks only.\n\nTSI_SOCK_ERR_WRITE_FAILED The TSI encountered an error performing a write to a socket.\n\nAction: Check the TSI log file just prior to this error for more detailed information.\n\nTSI_SOCKETA_ERR_BIND_FAILED TSI failed to bind a well-known port to its listening socket.\n\nAction: Make sure that your well-known port is not being used by any other application within your system. Terminate your application and try again.\n\nTSI_SOCKETA_ERR_FCNTL_FAILED TSI failed to set the socket file descriptor to a non-blocking I/O mode.\n\nAction: Ensure that your TCP/IP software package supports non-blocking I/O and that your application is configured to use non-blocking I/O. Otherwise, contact Protogate for further assistance.\nTSI_SOCKA_ERR_LISTEN_FAILED TSI failed to listen for a connection request through a well-known port specified in the TSI configuration file.\n\nAction: If this error occurs consistently, contact Protogate for further assistance.\n\nTSI_SOCKA_ERR_SETOPT_FAILED TSI failed to set TCP/IP TCP_NODELAY and KEEP_ALIVE options.\n\nAction: Ensure that your TCP/IP socket interface package supports these socket options. If your TCP/IP software does not support these options, consider turning them off using the TSI configuration file. Otherwise, contact Protogate for further assistance.\n\nTSI_SOCKA_ERR_SOCKET_FAILED TSI failed to obtain a new socket for the newly requested connection.\n\nAction: Consider increasing the maximum number of file descriptors through system resource services (UNIX: getrlimit function).\n\nTSI_SRVR_ERR_EVT_PROC_FAILED TSI failed to complete its internal event processing routine.\n\nAction: If this error occurs consistently, contact Protogate for further assistance. VxWorks only.\n\nTSI_SRVR_ERR_PIPE_CREATE_FAILED TSI failed to create a named pipe for its internal shared-memory protocol package.\n\nAction: If you develop a server-resident application, make sure your linkage completes successfully. VxWorks only.\n\nTSI_SRVR_ERR_PIPE_OPEN_FAILED TSI failed to open its internal named pipe.\n\nAction: Terminate your application and try again. VxWorks only.\nTSI_SRVR_ERR_SIG_ERR TSI failed to install an interrupt handler for SIGUSR1 signal.\n\nAction: Ensure that your TSI application in the VxWorks environment does not use the SIGUSR1 signal. VxWorks only.\n\nTSI_SRVR_ERR_TASK_VAR_FAILED TSI failed to add task variables to VxWorks system. Severe error.\n\nAction: Contact Protogate for further assistance. VxWorks only.\n### A.2 Command-Specific Error Codes\n\nTable A-1 lists alphabetically all the error codes related to specific TSI commands described in Chapter 4. These codes are returned in the global variable `tserrno`.\n\n**Table A-1: TSI Command-specific Error Codes**\n\n<table>\n<thead>\n<tr>\n<th>Command(s)</th>\n<th>Error Code</th>\n<th>Reference Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>tBufAlloc</td>\n<td>TSI_BUFA_ERR_NEVER_INIT</td>\n<td>page 81</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_BUFA_ERR_NO_BUFS</td>\n<td>page 81</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_BUFA_ERR_SEVERE_ERR</td>\n<td>page 81</td>\n</tr>\n<tr>\n<td>tBufFree</td>\n<td>TSI_BUFF_ERR_INVALID_BUF</td>\n<td>page 82</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_BUFF_ERR_NEVER_INIT</td>\n<td>page 82</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_BUFF_ERR_NOT_ALLOCATED</td>\n<td>page 82</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_BUFF_ERR_SEVERE_ERR</td>\n<td>page 83</td>\n</tr>\n<tr>\n<td>tConnect</td>\n<td>TSI_CONN_ERR_CLOSE_FAILED</td>\n<td>page 86</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_CONN_ERR_CONN_INIT_FAILED</td>\n<td>page 86</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_CONN_ERR_INVALID_PROT</td>\n<td>page 86</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_CONN_ERR_INVALID_STATE</td>\n<td>page 86</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_CONN_ERR_OPEN_FAILED</td>\n<td>page 86</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_CONN_ERR_QADD_FAILED</td>\n<td>page 86</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_CONN_ERR_RETRY_EXCEEDED</td>\n<td>page 87</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_CONN_ERR_SOCK_ALLOC_FAILED</td>\n<td>page 87</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_CONN_ERR_TINIT_FAILED</td>\n<td>page 87</td>\n</tr>\n<tr>\n<td>tDisconnect</td>\n<td>TSI_DISC_ERR_CLOSE_FAILED</td>\n<td>page 89</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_DISC_ERR_DISC_FAILED</td>\n<td>page 89</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_DISC_ERR_INVALID_ID</td>\n<td>page 89</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_DISC_ERR_INVALID_STATE</td>\n<td>page 89</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_DISC_ERR_INVALID_TYPE</td>\n<td>page 89</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_DISC_ERR_NEVER_INIT</td>\n<td>page 90</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_DISC_ERR_Q_NOT_EMPTY</td>\n<td>page 90</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_DISC_ERR_QADD_FAILED</td>\n<td>page 90</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_DISC_ERR_SEVERE_ERROR</td>\n<td>page 90</td>\n</tr>\n<tr>\n<td>Command(s) Causing Error</td>\n<td>Error Code</td>\n<td>Reference Page</td>\n</tr>\n<tr>\n<td>--------------------------</td>\n<td>-------------------------------------------------</td>\n<td>----------------</td>\n</tr>\n<tr>\n<td>tConnect</td>\n<td>TSI_EWOULDBLOCK</td>\n<td>page 87</td>\n</tr>\n<tr>\n<td>tDisconnect</td>\n<td></td>\n<td>page 90</td>\n</tr>\n<tr>\n<td>tListen</td>\n<td></td>\n<td>page 97</td>\n</tr>\n<tr>\n<td>tRead</td>\n<td></td>\n<td>page 111</td>\n</tr>\n<tr>\n<td>tWrite</td>\n<td></td>\n<td>page 122</td>\n</tr>\n<tr>\n<td>tInit</td>\n<td>TSI_INIT_ERR_ACT_ADD_REM_FAILED</td>\n<td>page 92</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_ACT_QINIT_FAILED</td>\n<td>page 92</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_ALREADY_INIT</td>\n<td>page 92</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_BUF_ADD_REM_FAILED</td>\n<td>page 92</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_BUF_QINIT_FAILED</td>\n<td>page 93</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_CFG_LOAD_FAILED</td>\n<td>page 93</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_LOG_INIT_FAILED</td>\n<td>page 93</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_NO_MEM</td>\n<td>page 93</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_NO_RESOURCE</td>\n<td>page 93</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_NO_TRACE_BUFFER</td>\n<td>page 94</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_SETRLIMIT_FAILED</td>\n<td>page 94</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_TASK_VAR_FAILED</td>\n<td>page 94</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_INIT_ERR_TSICB_ALLOC_FAILED</td>\n<td>page 94</td>\n</tr>\n</tbody>\n</table>\n### Table A-1: TSI Command-specific Error Codes (Cont’d)\n\n<table>\n<thead>\n<tr>\n<th>Command(s) Causing Error</th>\n<th>Error Code</th>\n<th>Reference Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>tListen</td>\n<td>TSI_LSTN_ERR_CLOSE_FAILED</td>\n<td>page 97</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_CONN_INIT_FAILED</td>\n<td>page 97</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_INVALID_PROT</td>\n<td>page 97</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_INVALID_STATE</td>\n<td>page 97</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_LSTN_FAILED</td>\n<td>page 98</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_NO_LISTENERS</td>\n<td>page 98</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_NOT_SERVER</td>\n<td>page 98</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_QADD_FAILED</td>\n<td>page 98</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_QFULL</td>\n<td>page 98</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_QINIT_FAILED</td>\n<td>page 98</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_SETOPT_FAILED</td>\n<td>page 98</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_SOCK_ALLOC_FAILED</td>\n<td>page 99</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_LSTN_ERR_TINIT_FAILED</td>\n<td>page 99</td>\n</tr>\n<tr>\n<td>tPoll</td>\n<td>TSI_POLL_ERR_BAD_PTR</td>\n<td>page 103</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_BUF_NOT_FOUND</td>\n<td>page 103</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_GETLIST_FAILED</td>\n<td>page 103</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_INTERNAL</td>\n<td>page 103</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_INVALID_ID</td>\n<td>page 104</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_INVALID_IOCTL</td>\n<td>page 104</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_INVALID_REQ_TYPE</td>\n<td>page 104</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_NEVER_INIT</td>\n<td>page 104</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_OVERFLOW</td>\n<td>page 104</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_QEMPTY</td>\n<td>page 104</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_QREM_FAILED</td>\n<td>page 105</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_READ_NOT_COMPLETE</td>\n<td>page 105</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_READ_TIMEOUT</td>\n<td>page 105</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_SOCK_CLOSED</td>\n<td>page 105</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_UNBIND</td>\n<td>page 106</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_WRITE_NOT_COMPLETE</td>\n<td>page 106</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POLL_ERR_WRITE_TIMEOUT</td>\n<td>page 106</td>\n</tr>\n</tbody>\n</table>\nTable A-1: TSI Command-specific Error Codes (Cont’d)\n\n<table>\n<thead>\n<tr>\n<th>Command(s) Causing Error</th>\n<th>Error Code</th>\n<th>Reference Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>tPost</td>\n<td>TSI_POST_ERR_CLIENT_INVALID_SEM</td>\n<td>page 107</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POST_ERR_NEVER_INIT</td>\n<td>page 107</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_POST_ERR_SERVER_INVALID_SEM</td>\n<td>page 108</td>\n</tr>\n<tr>\n<td>tRead</td>\n<td>TSI_READ_ERR_INTERNAL</td>\n<td>page 111</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_INVALID_BUF</td>\n<td>page 111</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_INVALID_ID</td>\n<td>page 111</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_INVALID_LENGTH</td>\n<td>page 111</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_INVALID_STATE</td>\n<td>page 111</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_LIMIT_EXCEEDED</td>\n<td>page 112</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_NEVER_INIT</td>\n<td>page 112</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_NO_BUFS</td>\n<td>page 112</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_OVERFLOW</td>\n<td>page 112</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_QADD_FAILED</td>\n<td>page 112</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_QFULL</td>\n<td>page 112</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_READ_TIMEOUT</td>\n<td>page 113</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_SELECT</td>\n<td>page 113</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR.SOCK_CLOSED</td>\n<td>page 113</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_READ_ERR_UNBIND</td>\n<td>page 113</td>\n</tr>\n<tr>\n<td>tSyncSelect</td>\n<td>TSI_SYNCSELECT_ERR_INVALID_STATE</td>\n<td>page 115</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_SYNCSELECT_ERR_SELECT_ERROR</td>\n<td>page 116</td>\n</tr>\n<tr>\n<td>rTerm</td>\n<td>TSI_TERM_ERR_ACT_REM_FAILED</td>\n<td>page 118</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_TERM_ERR_ACT_TERM_FAILED</td>\n<td>page 118</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_TERM_ERR_BUF_FREE_FAILED</td>\n<td>page 118</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_TERM_ERR_BUFM_TERM_FAILED</td>\n<td>page 118</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_TERM_ERR_DISC_FAILED</td>\n<td>page 118</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_TERM_ERR_LOG_END_FAILED</td>\n<td>page 118</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_TERM_ERR_NEVER_INIT</td>\n<td>page 118</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_TERM_ERR_RES_FREE_FAILED</td>\n<td>page 119</td>\n</tr>\n</tbody>\n</table>\n### Table A-1: TSI Command-specific Error Codes (Cont’d)\n\n<table>\n<thead>\n<tr>\n<th>Command(s) Causing Error</th>\n<th>Error Code</th>\n<th>Reference Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>tWrite</td>\n<td>TSI_WRIT_ERR_INTERNAL</td>\n<td>page 122</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_INVALID_BUF</td>\n<td>page 122</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_INVALID_ID</td>\n<td>page 122</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_INVALID_LENGTH</td>\n<td>page 122</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_INVALID_STATE</td>\n<td>page 122</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_INVALID_WRITE_TYPE</td>\n<td>page 123</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_LIMIT_EXCEEDED</td>\n<td>page 123</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_NEVER_INIT</td>\n<td>page 123</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_QADD_FAILED</td>\n<td>page 123</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_QFULL</td>\n<td>page 123</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_SELECT</td>\n<td>page 123</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_SOCK_CLOSED</td>\n<td>page 123</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_UNBIND</td>\n<td>page 124</td>\n</tr>\n<tr>\n<td></td>\n<td>TSI_WRIT_ERR_WRITE_TIMEOUT</td>\n<td>page 124</td>\n</tr>\n</tbody>\n</table>\nB.1 UNIX Environment\n\nIn a UNIX environment, the TSI gains access to non-blocking I/O services through the use of the UNIX signal delivery mechanism. At initialization, TSI installs a signal handler (or IOCH) to be executed upon delivery of the signal. When a signal is delivered to a TSI application, the TSI IOCH immediately suspends the delivery of that signal again until it completes its I/O services through the IOCH function. TSI exits the IOCH either when it runs out of system resources to accept additional I/O, or when it has no additional I/O to accept. In either case, system resources are tied up by TSI while it is in the IOCH function unless it is interrupted by another system service request (that is, another signal delivery) with a higher priority than its own. A TSI application using non-blocking I/O can provide TSI with its own IOCH; the TSI IOCH subsequently invokes the application IOCH after it completes its I/O services.\n\nIn short, non-blocking I/O operation is not only complex but also expensive. Therefore, it requires careful planning and design so that your application uses the system resources wisely.\n\nB.1.1 Blocking I/O operations\n\nBlocking I/O operation requires no IOCHs. Blocking I/O does not use any signal delivery mechanism to handle the delivery of data. Blocking I/O allows the orderly execution of your application and requires far less system resources than non-blocking I/O. Blocking I/O is also easier to debug and troubleshoot than non-blocking I/O. Careful design through the isolation of system and protocol dependency allows your applica-\ntion to work using either blocking I/O or non-blocking I/O. The TSI services allow your application to switch from blocking to non-blocking I/O, and vice versa, without the recompilation of your application code.\n\nIt is not efficient to handle multiple connections under blocking I/O operation, because your application is blocked until the data arrives or TSI times out while waiting. While your application is waiting for I/O in one connection, data from other connections is blocked.\n\nB.1.2 Non-Blocking I/O Operations\n\nThe TSI uses the SIGIO signal for its non-blocking BSD socket interface. Therefore, your application should not block the delivery of SIGIO signals (for example, sigprocmask) at any time, especially when expecting data from the network.\n\nIf you use non-blocking I/O, design your application with robust IOCH function(s). Also, the application IOCH should perform as little work as possible and, before it exits, use some notification techniques to awaken the main routines to perform the remaining tasks. Some possible notification techniques are system semaphores, sleep and wakeup calls using the SIGALRM signal, and so on.\n\nB.1.3 SOLARIS use of SIGALRM\n\nThe use of a default signal handler through SIGALRM signal can cause a system core dump inside the SOLARIS internal SIGALRM signal handler. You can work around it by providing your own signal handler for SIGALRM. The following code segment assists you in setting up a SIGALRM handler for the SIGALRM signal:\nvoid genSigHdlr ( int signal )\n{\n return;\n}\n\nvoid main ( )\n{\n struct sigaction SigAction;\n\n SigAction. sa_handler = genSigHdlr;\n sigfillset (&SigAction. sa_mask);\n SigAction. sa_flags = 0;\n\n if (sigaction (SIGALRM, &SigAction, (struct sigaction *)NULL) ==\n ERROR)\n {\n fprintf (stderr, \"sigaction failed %d\\n\", errno);\n return ERROR;\n }\n ..... return OK;\n}\n\nNotice that genSigHdlr does nothing but return to the system.\n\nB.1.4 Polling I/O Operations\n\nYour application can implement polling I/O operations if it uses TSI with non-blocking\nI/O but provides no IOCH functions. Since your application provides no mechanism\nfor TSI to notify it when an I/O condition occurs, your application must poll TSI for the\ncompletion of I/O requests that it posts to TSI. Polling I/O operations involve the tPoll\nfunction (Section 4.8 on page 100). Polling I/O is helpful if your application manages\nmultiple connections, data arrives at a predictable rate, and the timing of data is not\ncritical.\n\nB.2 VxWorks Environment\n\nThe TSI operates only in a VxWorks environment that is similar to that of the Freeway\nserver. VxWorks has several features similar to UNIX; however, it has a unique operat-\ning environment and a real-time operating system. The use of the TSI by an application\nthat runs on the Freeway server is often called a server-resident application (SRA). The SRA can be configured to interact with Protogate's message multiplexor subsystem through the shared-memory transport mechanism supported by TSI, or it can be configured to interact with other systems using the BSD socket interface which is also supported by TSI. Whichever transport your SRA program uses, you should understand not only the VxWorks operating system but also the way the Freeway server is configured and how Protogate implements TSI under VxWorks. For more information on SRAs, see Section 2.3.7 on page 43 and the Freeway Server-Resident Application and Server Toolkit Programmer Guide.\n\nB.2.1 Blocking I/O Operations\n\nBlocking I/O in VxWorks is similar to that of the UNIX environment.\n\nB.2.2 Non-Blocking I/O Operations\n\nNon-blocking I/O in VxWorks with Protogate's Freeway server requires your application to cooperate with other tasks. VxWorks on Freeway is configured to operate in a cooperative manner. This means that VxWorks operates as a non-preemptive multitasking environment. When your application does not have data to be processed, it must relinquish the CPU so that other tasks can run. You can use your own interrupt service routine to notify or resume your application when its data arrives.\n\nThe TSI uses a binary semaphore to support non-blocking I/O delivery from both network and shared-memory environments. Since VxWorks running on Freeway is configured for a cooperative environment, your application must also act cooperatively. Your application must call tPost immediately before relinquishing its control to VxWorks. Your application must relinquish the control through taskDelay, binary semaphores, or other means; otherwise, only your task has control of the CPU which prevents other important tasks from running.\n\nYour application should not use global variables freely if multiple instances of the same application are running concurrently. VxWorks global variables are shared among all\ntasks unless you define them as a particular task's variables (using taskVarAdd). Task variables are expensive to maintain by VxWorks and therefore should be used sparingly.\n\n**B.3 VMS Environment**\n\nThe TSI uses the process-level Asynchronous System Trap (AST) for non-blocking data delivery from the network. Therefore, your application should not block the delivery of ASTs (using sys$setast) at any time, especially when expecting data from the network.\nAppendix\n\nC\n\nTSI Logging and Tracing\n\nTo support debugging efforts, TSI provides tracing and logging services to troubleshoot both application and network problems.\n\nC.1 TSI Logging\n\nThere are two kinds of TSI logging services: general logging and connection-related logging. As the name implies, general logging includes error or information that is not related to any particular connection. Connection-related logging indicates error or information related to a specific connection. To monitor data, you must use the TSI tracing services described in Section C.2.\n\nGeneral logging is defined in the “main” section of the TSI text configuration file. The LogLev parameter (page 54) specifies the level of logging your application needs and can be from 0 to 7, with level 0 being no logging, level 1 being the most severe error, and 7 being the least severe. In the “main” section, the LogName parameter (page 54) defines the log file name where your logging information is to reside. The default file name is “tsilog”. If you wish logging information to be output to the screen, define LogName as “stdout.” The number of entries to “stdout” is unlimited. A disk file is limited to 1000 entries, and this number is not configurable.\n\nConnection-related logging can be defined in each individual TSI connection definition. You can log for some connections but not for the others; and different connections can log errors at different levels. All error codes are defined in Appendix A and in each individual function description (for example, tConnect in Section 4.4 on page 84).\nThe following is the format of the each log entry:\n\nSessX: TSI_YYY_ZZZ_Information(terno/errno)\n\nwhere:\n\nX is connection ID. For general logging, X will be 999. Otherwise, it indicates a connection-related entry.\n\nYYY is brief function name of TSI. For example, if ZZZ is CONN it indicates the log entry is from tConnect function.\n\nZZZ can be ERR or INFO. ERR indicates an error condition; INFO indicates information only.\n\nterrno is a TSI error code for this entry; errno is the last encountered ‘C’ errno value.\n\nC.2 TSI Tracing\n\nC.2.1 Trace Definitions\n\nThe TSI tracing facility captures and stores real-time data in its internal wrap-around buffer. The size of this buffer is configurable up to 1 megabyte of memory. There are two kinds of TSI tracing: general tracing and connection-specific tracing. In general tracing, trace data has no connection-specific information, whereas connection-specific trace data pertains to only one specific connection ID.\n\nTo activate tracing, first specify the TSI “main” configuration parameters. Specify the TraceSize parameter (page 55) up to 1 megabyte of memory. The TraceName parameter (page 55) defines the file name where your trace information is to reside.\n\nSpecify the level of tracing using the TraceLev parameter (page 55). This parameter defaults to zero if not defined (no tracing). The TraceLev parameter can be defined in the “main” section for general tracing or in each individual connection definition (page 56). Each connection definition can have a different TraceLev value.\nThe TraceLev parameter can be the sum of one or more of the following values:\n\n1 = trace the read (input) data\n\n2 = trace the write (output) data\n\n4 = trace the TSI interrupt services\n\n8 = trace the application IOCH services\n\n16 = trace the user’s data\n\nFor example, if you want to trace both read and write data, specify 3 for the TraceLev parameter. If you want to trace read, write, and user’s data, specify 19 for the TraceLev parameter.\n\nThe most commonly used trace level is for I/O passing through the TSI service layer (TraceLev = 3). TSI also provides the interrupt and application I/O completion handler (IOCH) trace levels within TSI to assist the application in troubleshooting the IOCH mechanism. The user data trace level allows the application to store its own data in the trace buffer.\n\n---\n\n**Note**\n\nTSI does not decode user data with its tsidecode program (Section C.2.2).\n\n---\n\nYou can turn tracing on or off at any time after TSI is initialized using tPoll with the TSI_POLL_TRACE_ON or TSI_POLL_TRACE_OFF options. Tracing is done internally with the TSI trace buffer. Trace data is not written to the trace file until tTerm is called or tPoll is called with the TSI_POLL_TRACE_WRITE option. Therefore, your application should always call tTerm before it exits to the operating system. If tracing is required and is defined in the TSI configuration file, it is automatically on when tInit is called. You can use tPoll with the TSI_POLL_TRACE_STORE option to store your own...\ntrace buffer inside the TSI trace buffer. Refer to \\texttt{tPoll} (Section 4.8 on page 100) for more information. Since TSI tracing does not involve disk I/O until \\texttt{tTerm} is executed, there is little or no performance impact.\n\n\\subsection*{C.2.2 Decoded Trace Layout}\n\nYou can run either the \\texttt{tsidecode} or \\texttt{dlidecode} program against the trace file produced by TSI (run \\texttt{dlidecode} only if your application is using DLI). The decoded output is displayed on the screen for UNIX-like systems. In VMS, the decoded output is written to the file named \\texttt{tsi.sum} (or \\texttt{dli.sum}). You can run \\texttt{dlidecode} against the trace file produced by either DLI or TSI. Refer to the Freeway Data Link Interface Reference Guide for details on DLI tracing.\n\nThe format of the decoded trace can be described as follows. See Section C.2.3 for an actual decoded trace example.\n\n- line 1: Protogate 2000(C) TSI Trace Decoder\n- line 2: Max buffer size: xyz\n- line 3: TRACE SOURCE: yyy\n- line 4: @@@@@ Actual Data offset aa Size = bb\n- line 5: cc: hex data and printable ascii equivalent.\n- line 6: @@@@@ Decode begins\n- line 7: dd(desc) Conn ee: time and date\n- line 8: TSI header info:\n- line 9: iHdrLen = ff iDataLen = gg uiSeqNo = hh\n- line 10: iPacketType (ii) = textii iCmd (jj) = textjj\n- line 11: DATA : hex data and printable ascii equivalent.\n\nEach line of the above format is explained as follows:\n\n- line 1: indicates the copyright and the name of the \\texttt{tsidecode} program. Note that \\texttt{tsidecode} can run only against the TSI trace file, unlike \\texttt{dlidecode} which can run on both DLI and TSI trace files.\n\n- line 2: prints the currently used maximum buffer size that is defined in the TSI configuration file (\\texttt{MaxBufSize} on page 55). Note that the size excludes the over-\nhead used by TSI; it describes the maximum number of actual data bytes allowed by TSI. See Section 2.3 on page 31.\n\nline 3: prints the source of the trace.\n\nline 4: describes the actual offset (aa) from the beginning of the trace file where this packet is stored and the number of bytes contained in this packet has (bb). Section C.2.4 describes how to read the TSI trace file in case you want to write your own decoder to decode your own trace data that you store in TSI trace buffer using tPoll with the TSI_POLL_TRACE_STORE option.\n\nline 5: prints the actual hex values and their equivalent printable ASCII text. The offset (cc) is the actual offset from the beginning of the packet, based on 0. Each line contains up to 16 bytes from the trace packet. Note that line 5 can be repeated if the actual size of the trace packet is more than 16 bytes long.\n\nline 6: indicates that the actual decoding begins. This is where the headers are broken into individual fields.\n\nline 7: dd indicates the direction of the packet; dd can be =====> to indicate an outgoing packet or <===== to indicate an incoming packet. For non-I/O related packets (for example, user's data packet), dd is either ***** or ######. If the trace packet is for I/O, desc can be READ(1)/WRITE(2) n bytes. If the packet is a non-I/O packet, desc can be one of the following:\n\nCONNECTION INTERRUPT BEGINS(4): indicates that TSI begins its interrupt handler to process I/O requests.\n\nCONNECTION INTERRUPT ENDS(5): indicates that TSI ends its interrupt handler routine and is ready to return to TSI.\n\nCONNECTION ISR(3): indicates that TSI is about to call the IOCH of a specific\nconnection ID. The address of this IOCH was provided to TSI through the \\texttt{tConnect} function.\n\n\\textbf{APPLICATION ISR BEGINS(6)}: indicates that TSI is about to call the generic IOCH that was provided by the application to TSI through the \\texttt{tInit} function.\n\n\\textbf{APPLICATION ISR ENDS(7)}: indicates that the generic IOCH routine returns control to TSI.\n\n\\textbf{AT(8)}: indicates that this trace buffer belongs to the application. The \\texttt{tsidecode} program will not attempt to decode this packet. You have to write your own decode function to interpret your own data packet.\n\nline 8: begins the TSI header information.\n\nline 9 and line 10: show detailed information of the TSI header.\n\nline 11: indicates the details of the data in both hex values and printable ASCII equivalent.\n\n\\textbf{C.2.3 Example \\texttt{tsidecode} Program Output}\n\nThe following are example segments of decoded trace output from the TSI trace file using the \\texttt{tsidecode} program (output using the \\texttt{dlidecode} program would be virtually identical except for the first few lines):\n\n\\begin{verbatim}\nProtogate 2000(C) TSI Trace Decoder\nMax buffer size: 564\n-------------------------------------------------------------------------------\n@@@@@ Actual Data offset 8 Size = 0\n@@@@@ Decoding begins\nERROR\n DATA : 00 00 00 00 00 00 00 00 00 2e a8 3d 6a\n ...........=j\n\\end{verbatim}\n@@ @ @@ @ Actual Data offset 20 Size = 30\n000000: 00 00 00 14 00 00 00 0a 00 00 00 00 00 00 01 00 01 ................\n000016: 00 01 00 01 02 34 00 14 00 00 00 00 00 00 ....4........\n@@ @ @@ @ Decoding begins\n\n====>(WRITE 30 bytes)Conn 0: Fri Oct 21 15:15:07 1994\n\nTSI header info:\niHdrLen = 20 iDataLen = 10 uiSeqNo = 0\niPacketType(1) = CONTROL iCmd(1) = BIND\n\nTSI BIND info:\niMaxBufSize = 564 iMaxHdrSize = 20\nSegmenting = NO Buffering = NO Negotiable = NO\n\n@@ @ @@ @ Actual Data offset 62 Size = 30\n000000: 00 00 00 14 00 00 00 0a 00 00 00 00 00 00 00 00 01 00 01 ................\n000016: 00 01 00 01 02 34 00 14 00 00 00 00 00 00 ....4........\n@@ @ @@ @ Decoding begins\n\n\nTSI header info:\niHdrLen = 20 iDataLen = 10 uiSeqNo = 0\niPacketType(1) = CONTROL iCmd(1) = BIND\n\nTSI BIND info:\niMaxBufSize = 564 iMaxHdrSize = 20\nSegmenting = NO Buffering = NO Negotiable = NO\n\n@@ @ @@ @ Actual Data offset 104 Size = 20\n000000: 00 00 00 14 00 00 00 00 0a 00 00 00 00 00 00 00 00 01 00 01 ................\n000016: 00 01 00 01 02 34 00 14 00 00 00 00 00 00 ....4........\n@@ @ @@ @ Decoding begins\n\n====>(READ 20 bytes)Conn 0: Fri Oct 21 15:15:07 1994\n\nTSI header info:\niHdrLen = 20 iDataLen = 0 uiSeqNo = 6\niPacketType(1) = CONTROL iCmd(6) = ACK\n@@@ Actual Data offset 136 Size = 96\n 000000: 00 00 00 14 00 00 00 4c 00 00 00 01 00 02 00 00 ......L......\n 000016: 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 0a 00 16 ..........\n 000032: 00 01 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 .........\n 000048: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ......\n 000064: 69 63 70 30 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 icp0......\n 000080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ...........\n@@@ Decoding begins\n\n====>(WRITE 96 bytes)Conn 0: Fri Oct 21 15:15:07 1994\n\nTSI header info:\niHdrLen = 20 iDataLen = 76 uiSeqNo = 1\niPacketType(2) = DATA iCmd(0) =\n\n DATA : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 16 00 01 00 01 ............\n DATA : 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ......\n DATA : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ......\n DATA : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ......\n DATA : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ......\n\n@@@ Actual Data offset 244 Size = 20\n 000000: 00 00 00 14 00 00 00 00 00 00 00 00 00 06 00 01 00 06 ............\n 000016: 00 01 00 01 ....\n@@@ Decoding begins\n\n\nTSI header info:\niHdrLen = 20 iDataLen = 0 uiSeqNo = 6\niPacketType(1) = CONTROL iCmd(6) = ACK\n\n@@@ Actual Data offset 276 Size = 96\n 000000: 00 00 00 14 00 00 00 4c 00 00 00 01 00 02 00 00 ......L......\n 000016: 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 0a 00 16 ..........\n 000032: 00 01 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 .........\n 000048: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ......\n 000064: 69 63 70 30 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 icp0......\n 000080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ...........\n@@@ Decoding begins\n\nTSI header info:\niHdrLen = 20 iDataLen = 76 uiSeqNo = 1\niPacketType(2) = DATA iCmd(0) =\n\nDATA : 00 00 00 00 00 00 00 00 00 00 0a 00 16 00 01 00 01 ............\nDATA : 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 ................\nDATA : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ...............\nDATA : 00 00 00 00 00 00 00 00 00 00 00 00 69 63 70 30 ............icp0\nDATA : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ...............\nDATA : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ...............\n\n-------------------------------------------------------------------------------\n\n@@@@@ Actual Data offset 384 Size = 20\n\n000000: 00 00 00 14 00 00 00 40 00 00 00 01 00 02 00 00 ......@....... 000016: 00 01 00 01 ....\n\n@@@@@ Decoding begins\n\n<==== (READ 20 bytes) Conn 0: Fri Oct 21 15:15:07 1994\n\nTSI header info:\niHdrLen = 20 iDataLen = 64 uiSeqNo = 1\niPacketType(2) = DATA iCmd(0) =\n\n-------------------------------------------------------------------------------\n\n@@@@@ Actual Data offset 416 Size = 64\n\n000000: 00 00 00 00 00 00 00 00 0a 00 16 00 01 00 01 ............\n000016: 00 00 00 00 00 03 00 00 00 00 00 00 00 00 00 00 ............\n000032: 00 00 00 14 00 00 00 00 00 00 00 00 03 00 00 46 72 65 65 77 61 79 20 52 65 6c 65 61 73 65 20 32 2e 30 00 way Release 2.0.\n\n@@@@@ Decoding begins\n\n<==== (READ 64 bytes) Conn 0: Fri Oct 21 15:15:07 1994\n\nDATA : 00 00 00 00 00 00 00 00 0a 00 16 00 01 00 01 ............\nDATA : 00 00 00 00 00 03 00 00 00 00 00 00 00 00 00 00 ............\nDATA : 00 00 00 14 00 00 00 00 00 00 00 03 00 00 46 72 65 65 77 61 79 20 52 65 6c 65 61 73 65 20 32 2e 30 00 way Release 2.0.\n\n-------------------------------------------------------------------------------\nC.2.4 Trace Binary Format\n\nYou can use the following information to write your own decoder if you need to provide your own trace information. The trace file format is shown in Figure C-1.\n\n```\ntypedef struct _TRACE_FCB\n{\n int iMaxBufSize;\n short iTraceSource;\n short iPadding;\n} TRACE_FCB, *PTRACE_FCB;\n```\n\nFigure C-1: TSI Trace File Format\n\nFigure C-2 shows the TRACE_FCB ‘C’ structure.\n\n```\ntypedef struct _TRACE_FCB\n{\n int iMaxBufSize;\n short iTraceSource;\n short iPadding;\n} TRACE_FCB, *PTRACE_FCB;\n```\n\nFigure C-2: TRACE_FCB ‘C’ Structure\nFigure C-3 shows the format of each trace packet in the TSI_TRACE_HDR ‘C’ structure.\n\ntypedef struct _TSI_TRACE_HDR\n{\n unsigned short usTrcType; /* type of tracing */\n unsigned short usTrcConnID; /* current connection ID */\n int iTrcDataSize; /* size of the trace packet */\n time_t tTrcTime; /* time stamp */\n} TSI_TRACE_HDR, *PTSI_TRACE_HDR;\n\n**Figure C-3:** TSI_TRACE_HDR ‘C’ Structure\n\n### C.3 Freeway Server Tracing\n\nTracing service is also provided from the Freeway server. Refer to the Freeway User Guide for more information. You can use the trace information from both the client application and the Freeway server to diagnose and troubleshoot your client application. The Freeway trace service is identical to that of the client application; however, the direction of the trace is the reverse of that of the client. For example, for the same data packet, the client would indicate a read packet while the server would indicate a write packet. Care therefore must be taken when translating the two traces.\nIndex\n\nA\nAsynchronous I/O see Non-blocking I/O\nAsyncIO TSI parameter 54, 56, 65\nAudience 11\n\nB\nBinary configuration files\nmanagement 52\nBit numbering 15\nBlocking I/O 30\n signal processing 45\n UNIX 143\n VxWorks 146\nBSC msgBlkSize parameter 32, 33, 34\nBuffer management 31\n allocation and release 40\n buffer size negotiation 39\n cautions 41\n client buffers 32\n client configuration 35\n client versus server-resident 43\n connection-specific buffers 38\n example calculation 33\n headers 41\n ICP buffers 32\n muxCfg file 41\n see Functions\n server buffers 33\n TSI buffer pool definition 36\n using your own buffers 41\nByte ordering 15\n\nC\nCaution\n\ndata loss 73\n signal processing 45\nClient buffer configuration 35\nClient buffers 32\n allocation and release 40\n connection-specific 38\nClient-server environment 22\n summary of steps 23\nConcepts of TSI 29\nConfiguration 29, 47\n binary files\n management 52\n client buffers 35\n error messages 67\n file\n example 60\n grammar (PDL) 69\n language 50\n on-line processing 52\n system 37, 76\nTSI 47\n asyncIO parameter 54, 56, 65\n binary file 50\n dualAddress parameter 54\n interruptTrace parameter 54\n localPort parameter 58\n logLev parameter 54, 56, 149\n logName parameter 54, 149\n main parameters 54\n maxBuffers parameter 36, 41, 44, 54, 65, 77, 80\n maxBufSize parameter 33, 36, 37, 38, 39, 40, 41, 44, 55, 56, 65, 77, 152\n maxConns parameter 44, 55, 77, 85, 96\n maxErrors parameter 56, 79\nmaxInQ parameter 44, 56, 79\nmaxOutQ parameter 44, 56, 79\nnon-transport specific 56\nserver parameter 57, 60, 61, 63\nserverName parameter 55, 62, 63\nshared memory transport 59\nexample 62\nshmKey parameter 59\nshmMaxInQ parameter 59\nshmMaxOutQ parameter 59\nshmPeerName parameter 59, 62, 64\nSimpact server 65\nexample 66\nstackSize parameter 55\nsummary 47\nTCP/IP socket transport 58\nexample 60\nTCPKeepAlive parameter 58\nTCPNoDelay parameter 58\ntimeout parameter 45, 57\ntraceLev parameter 55, 57, 150, 151\ntraceName parameter 55, 150\ntraceSize parameter 55, 150\ntransport parameter 57, 60, 62, 65\nwellKnownPort parameter 58, 60, 61\ntsicfg program 48\nrules 51\nConfiguration parameters\nconnection definition\nnon-transport specific 56\nshared memory transport 59\nTCP/IP socket transport 58\nmain definition 54\nConfiguration preprocessor\nsee tsicfg program\nConnection\ndefinition 53\ndefinition list 78\nmain definition 54\nnon-transport specific 56\nshared memory transport 59\nexample 62\nstatus 78\nTCP/IP socket transport 58\nexample 60\nConnection status 39, 40\nConnection-specific buffers 38\nContext free grammar 69\nCustomer support 16\nD\nData\ncautions, data loss 73\nData structures 76\nconnection definition 78\nconnection status 78\nsystem configuration 76\nData transfer\nsee also Functions\nDLI configuration parameters\nBSC msgBlkSize 32, 33, 34\nDLI header 38\nDLITE embedded interface 18\nDocuments\nreference 12\nDownload software 23\nDualAddress TSI parameter 54\nE\nElectrical interface 21\nEmbedded ICP\noverview 18\nError codes 125\ncommand-specific 137\ninternal 125\nsee also Functions (return codes listed under each function)\ntserro global variable 71, 125, 137\nTSI_READ_ERR_OVERFLOW 41, 110\nTSI_READ_ERR_QFULL 109\nTSI_WRIT_ERR_INVALID_LENGTH 39, 41\nTSI_WRIT_ERR_QFULL 120\nError handling\nTSI logging 149\nError messages\ntsicfg 67\nEthernet 21\nExamples\ncalculation of buffer sizes 33\nconfiguration file 60\nF\nFeatures\n product 21\n TSI 25\nFiles\n binary configuration\n management 52\n muxCfg 41\n on-line configuration 52\n see also Configuration, file\n server MuxCfg configuration 65\n example 66\nFreeway\n client-server environment 22\n configuration 29\n overview 18\nFunctions\n categories 72\n dIO\n DLI_POLL_GET_SESS_STATUS\n option 38, 40\n syntax synopsis 74\ntBufAlloc 40, 74, 80\n return codes 81, 137\ntBufFree 41, 75, 82\n return codes 82, 137\ntConnect 74, 84\n return codes 85, 137\ntDisconnect 75, 88\n return codes 89, 137\n tlnit 74, 91\n return codes 92, 138\ntListen 74, 95\n return codes 96, 139\ntPoll 74, 100\n return codes 103, 139\n TSI_POLL_GET_CFG_LIST option 78\n TSI_POLL_GET_CONN_STATUS\n option 39, 40, 78\n TSI_POLL_GET_SESS_STATUS option 84\n TSI_POLL_GET_SYS_CFG option 37, 76, 80\ntPost 74, 107\n return codes 107, 140\ntRead 74, 109\n return codes 110, 140\ntSyncSelect 75, 114\n return codes 115, 140\ntTerm 75, 117\n return codes 118, 140\ntWrite 74, 120\n return codes 121, 141\nG\nGrammar\n context free 69\n PDL 69\nH\nHeaders\n DLI 38\n example 38\n TSI 37, 41\nHistory of revisions 15\nI\nICP buffers 32\nInternet addresses 23\nInterruptTrace TSI parameter 54\nI/O\n blocking vs non-blocking 30\n completion handler (IOCH) 31, 143\n poll 145\n signal processing 45\n UNIX environment 143\n VxWorks environment 145\nL\nLAN interface processor 18\nLibrary\n TSI reference 50\nLocalPort TSI parameter 58\nLogging services 149\nLogLev TSI parameter 54, 56, 149\nLogName TSI parameter 54, 149\nM\nMaxBuffers TSI parameter 36, 41, 44, 54, 65, 77, 80\nMaxBufSize TSI parameter 33, 36, 37, 38, 39,\nFreeway Transport Subsystem Interface Reference Guide\n\n40, 41, 44, 55, 56, 65, 77, 152\nMaxConns TSI parameter 44, 55, 77, 85, 96\nMaxErrors TSI parameter 56, 79\nMaxInQ TSI parameter 44, 56, 79\nMaxOutQ TSI parameter 44, 56, 79\nmsgBlkSize BSC parameter 32, 33, 34\nMuxCfg file 41\nMuxCfg server configuration file 65\nexample 66\nFiles\nserver MuxCfg configuration 33, 40, 41\n\nN\nNegotiation of buffer size 39\nNon-blocking I/O 30\nI/O completion handler 31\nsignal processing 45\nUNIX 144\nVxWorks 146\n\nO\nOn-line configuration file processing 52\nOperating system\nProtoGate's real-time 18\nOverview\nembedded ICP 18\nFreeway server 18\nproduct 17\nTSI 25\n\nP\nPoll I/O 145\nUNIX 145\nProduct\nfeatures 21\noverview 17\nsupport 16\n\nR\nReference documents 12\nResource requirements 44\nRevision history 15\nrlogin 21\n\nS\nServer buffers 33\nServer processor 18\nServer TSI parameter 57, 60, 61, 63\nServerName TSI parameter 55, 62, 63\nServer-resident application 22, 43, 57, 59, 146\nSession status 84\nShmKey TSI parameter 59\nShmMaxInQ TSI parameter 59\nShmMaxOutQ TSI parameter 59\nShmPeerName TSI parameter 59, 62, 64\nSIGALRM 144\nSIGIO 144\nSignal processing 45\nSNMP 21\nSoftware\ndownload 23\nSolaris 144\nStackSize TSI parameter 55\nStatus\nconnection 39, 40, 78\nsession 84\nSupport, product 16\nSynchronous I/O\nsee Blocking I/O\nSystem\nconfiguration 37, 76\nresource requirements 44\n\nT\ntBufAlloc (see also Functions) 80\ntBufFree (see also Functions) 82\ntConnect (see also Functions) 84\nTCP/IP 21\nTCPKeepAlive TSI parameter 58\nTCPNoDelay TSI parameter 58\ntDisconnect (see also Functions) 88\nTechnical support 16\ntelnet 21\nTimeout TSI parameter 45, 57\ntInit (see also Functions) 91\ntListen (see also Functions) 95\ntPoll (see also Functions) 100\ntPost (see also Functions) 107\nTraceLev TSI parameter 55, 57, 150, 151\nTraceName TSI parameter 55, 150\nTraceSize TSI parameter 55, 150\nTracing services 149, 150\n binary format 158\n example 154\n file layout 152\n Freeway server 159\nTransport TSI parameter 57, 60, 62, 65\ntRead (see also Functions) 109\nTroubleshooting 149\nterrno global variable 71, 125, 137\nTSI\n concepts 29\n configuration 47\n see also Configuration, TSI\ndata structures 76\nerror codes 125\nerror handling 71\nfeatures 25\nfunctions 71, 73\n see also Functions\n syntax synopsis 74\noverview 25\nreference library 50\nTSI buffer pool definition 36\ntsicfg program 47, 48\n error messages 67\ntSyncSelect (see also Functions) 114\ntTerm (see also Functions) 117\ntWrite (see also Functions) 120\n\nU\nUNIX environment 143\n\nV\nVMS environment 147\nVxWorks 18\nVxWorks environment 145\n\nW\nWAN interface processor 18\nWellKnownPort TSI parameter 58, 60, 61\nCustomer Report Form\n\nWe are constantly improving our products. If you have suggestions or problems you would like to report regarding the hardware, software or documentation, please complete this form and mail it to Protogate at 12225 World Trade Drive, Suite R, San Diego, CA 92128, or fax it to (877) 473-0190.\n\nIf you are reporting errors in the documentation, please enter the section and page number.\n\nYour Name: ____________________________________________\n\nCompany: ____________________________________________\n\nAddress: ____________________________________________\n\n_____________________________________________________\n\nPhone Number: _______________________________________\n\nProduct: ____________________________________________\n\nProblem or Suggestion: __________________________________\n\n_________________________________________________________________\n\n_________________________________________________________________\n\n_________________________________________________________________\n\n_________________________________________________________________\nProtogate, Inc.\nCustomer Service\n12225 World Trade Drive, Suite R\nSan Diego, CA 92128"}}},{"rowIdx":80,"cells":{"id":{"kind":"string","value":"acfd6030ef882a70163bc382d340edf425d13cae"},"text":{"kind":"string","value":"6.1\n\nProlog++\n\nReference\n\nby Dave Westwood\nWIN-PROLOG 6.1\n\nThe contents of this manual describe the product, BDS-PROLOG for Windows (hereinafter called WIN-PROLOG) and one or more of its LPA Toolkits, and are believed correct at the time of going to press. They do not embody a commitment on the part of Logic Programming Associates (LPA), who may from time to time make changes to the specification of the product, in line with their policy of continual improvement. No part of this manual may be reproduced or transmitted in any form, electronic or mechanical, for any purpose without the prior written agreement of LPA.\n\nCopyright (c) 2017 Logic Programming Associates Ltd. All Rights Reserved.\n\nAuthors: Rebecca Shalfield, Clive Spenser, Brian D Steel and Alan Westwood\n\nLogic Programming Associates Ltd\nPO Box 226\nCranleigh\nSurrey\nGU6 9DL\nEngland\n\nphone: +44 (0) 20 8871 2016\nweb site: http://www.lpa.co.uk\n\n\n19 July, 2017\n# Contents\n\n<table>\n<thead>\n<tr>\n<th>Contents</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Welcome</td>\n<td>9</td>\n</tr>\n<tr>\n<td>An Object-Oriented View Of Prolog++</td>\n<td>10</td>\n</tr>\n<tr>\n<td>How To Use This Manual</td>\n<td>11</td>\n</tr>\n<tr>\n<td>Part 1 Object-Oriented Programming Systems</td>\n<td>12</td>\n</tr>\n<tr>\n<td>Part 2 Case Studies</td>\n<td>13</td>\n</tr>\n<tr>\n<td>Part 3 Technical Specification</td>\n<td>13</td>\n</tr>\n<tr>\n<td>Part 4 Operational Features</td>\n<td>13</td>\n</tr>\n<tr>\n<td>Part 1 - Object-Oriented Programming Systems</td>\n<td>14</td>\n</tr>\n<tr>\n<td>Chapter 1 - General Concepts Of OOPS</td>\n<td>15</td>\n</tr>\n<tr>\n<td>Definitions</td>\n<td>15</td>\n</tr>\n<tr>\n<td>OOPS</td>\n<td>16</td>\n</tr>\n<tr>\n<td>Classes and Instances</td>\n<td>17</td>\n</tr>\n<tr>\n<td>Abstraction</td>\n<td>17</td>\n</tr>\n<tr>\n<td>Encapsulation</td>\n<td>19</td>\n</tr>\n<tr>\n<td>Message Passing</td>\n<td>19</td>\n</tr>\n<tr>\n<td>Polymorphism</td>\n<td>19</td>\n</tr>\n<tr>\n<td>Inheritance</td>\n<td>20</td>\n</tr>\n<tr>\n<td>Singular Inheritance</td>\n<td>20</td>\n</tr>\n<tr>\n<td>Multiple Inheritance</td>\n<td>21</td>\n</tr>\n<tr>\n<td>Binding</td>\n<td>21</td>\n</tr>\n<tr>\n<td>Early Binding</td>\n<td>21</td>\n</tr>\n<tr>\n<td>Late Binding</td>\n<td>21</td>\n</tr>\n<tr>\n<td>Data-Driven Programming</td>\n<td>21</td>\n</tr>\n<tr>\n<td>Chapter 2 - A Logical Approach To OOPS</td>\n<td>23</td>\n</tr>\n<tr>\n<td>Prolog as a Logic-Based Language</td>\n<td>23</td>\n</tr>\n<tr>\n<td>Variable Types</td>\n<td>23</td>\n</tr>\n<tr>\n<td>Data Structures</td>\n<td>24</td>\n</tr>\n<tr>\n<td>How OOPS Can Benefit From Prolog</td>\n<td>24</td>\n</tr>\n<tr>\n<td>How OOPS Can Enhance Prolog</td>\n<td>25</td>\n</tr>\n<tr>\n<td>Some Prolog-Based OOPS</td>\n<td>26</td>\n</tr>\n<tr>\n<td>LOS</td>\n<td>26</td>\n</tr>\n<tr>\n<td>LAP</td>\n<td>26</td>\n</tr>\n<tr>\n<td>Chapter 3 - The Prolog++ Approach To OOPS</td>\n<td>27</td>\n</tr>\n<tr>\n<td>OOPS Features Of Prolog++</td>\n<td>27</td>\n</tr>\n<tr>\n<td>Class Hierarchies And Inheritance</td>\n<td>27</td>\n</tr>\n<tr>\n<td>Polymorphism And Message Broadcasting</td>\n<td>27</td>\n</tr>\n<tr>\n<td>Encapsulation And Abstraction</td>\n<td>28</td>\n</tr>\n<tr>\n<td>Data-Driven Programming</td>\n<td>28</td>\n</tr>\n<tr>\n<td>The Inheritance Mechanism Of Prolog++</td>\n<td>28</td>\n</tr>\n<tr>\n<td>Singular Inheritance</td>\n<td>28</td>\n</tr>\n<tr>\n<td>Multiple Inheritance</td>\n<td>29</td>\n</tr>\n<tr>\n<td>The Binding Process</td>\n<td>30</td>\n</tr>\n<tr>\n<td>Early Binding</td>\n<td>31</td>\n</tr>\n<tr>\n<td>Late Binding</td>\n<td>31</td>\n</tr>\n</tbody>\n</table>\n\n*Prolog++ Reference*\n<table>\n<thead>\n<tr>\n<th>Contents</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Forced Late Binding</td>\n</tr>\n<tr>\n<td>How Prolog++ Benefits From Prolog</td>\n</tr>\n<tr>\n<td>How Prolog++ Enhances Prolog</td>\n</tr>\n<tr>\n<td>Prolog++ And Smalltalk</td>\n</tr>\n<tr>\n<td>General</td>\n</tr>\n<tr>\n<td>Environment</td>\n</tr>\n<tr>\n<td>Classes</td>\n</tr>\n<tr>\n<td>Methods and Messages</td>\n</tr>\n<tr>\n<td>Messages may be cascaded.</td>\n</tr>\n<tr>\n<td>There are several types of message:</td>\n</tr>\n<tr>\n<td>Objects</td>\n</tr>\n<tr>\n<td>Inheritance</td>\n</tr>\n<tr>\n<td>Encapsulation</td>\n</tr>\n<tr>\n<td>Polymorphism</td>\n</tr>\n<tr>\n<td>Data Abstraction</td>\n</tr>\n<tr>\n<td>Prolog++ And C++</td>\n</tr>\n<tr>\n<td>General</td>\n</tr>\n<tr>\n<td>Environment</td>\n</tr>\n<tr>\n<td>Classes</td>\n</tr>\n<tr>\n<td>Methods and Messages</td>\n</tr>\n<tr>\n<td>Objects</td>\n</tr>\n<tr>\n<td>Inheritance</td>\n</tr>\n<tr>\n<td>Encapsulation</td>\n</tr>\n<tr>\n<td>Polymorphism</td>\n</tr>\n<tr>\n<td>Operator overloading</td>\n</tr>\n<tr>\n<td>Data Abstraction</td>\n</tr>\n<tr>\n<td>Part 2 - Case Studies In Prolog++</td>\n</tr>\n<tr>\n<td>Chapter 4 - Introduction To The Case Studies</td>\n</tr>\n<tr>\n<td>Chapter 5 - A Case Study In Simulation</td>\n</tr>\n<tr>\n<td>The Problem</td>\n</tr>\n<tr>\n<td>The Classes</td>\n</tr>\n<tr>\n<td>The "clock" Class</td>\n</tr>\n<tr>\n<td>The "bank" Class</td>\n</tr>\n<tr>\n<td>The "bank maths" Class</td>\n</tr>\n<tr>\n<td>The "teller" Class</td>\n</tr>\n<tr>\n<td>The "customer" Class</td>\n</tr>\n<tr>\n<td>The "customer_queue" Class</td>\n</tr>\n<tr>\n<td>The Output</td>\n</tr>\n<tr>\n<td>Single, Communal Queue</td>\n</tr>\n<tr>\n<td>Multiple, Personal Queues</td>\n</tr>\n<tr>\n<td>Chapter 6 - A Case Study In Resource Management</td>\n</tr>\n<tr>\n<td>The Problem</td>\n</tr>\n<tr>\n<td>The Classes</td>\n</tr>\n<tr>\n<td>The "timetable" Class</td>\n</tr>\n<tr>\n<td>The form Class</td>\n</tr>\n<tr>\n<td>The "period" Class</td>\n</tr>\n<tr>\n<td>The "teacher" Class</td>\n</tr>\n<tr>\n<td>The "subject" Class</td>\n</tr>\n<tr>\n<td>Contents</td>\n</tr>\n<tr>\n<td>-------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Calling Prolog From Prolog++</td>\n</tr>\n<tr>\n<td>Calling Prolog++ From Prolog</td>\n</tr>\n<tr>\n<td>Chapter 11 - The "prolog_plus_plus" Class</td>\n</tr>\n<tr>\n<td>compile/2</td>\n</tr>\n<tr>\n<td>create/1</td>\n</tr>\n<tr>\n<td>create/2</td>\n</tr>\n<tr>\n<td>create/3</td>\n</tr>\n<tr>\n<td>delete/0</td>\n</tr>\n<tr>\n<td>delete_all/0</td>\n</tr>\n<tr>\n<td>dump/1</td>\n</tr>\n<tr>\n<td>dump/2</td>\n</tr>\n<tr>\n<td>duplicate/1</td>\n</tr>\n<tr>\n<td>isa_class/0</td>\n</tr>\n<tr>\n<td>isa_instance/0</td>\n</tr>\n<tr>\n<td>kill/0</td>\n</tr>\n<tr>\n<td>load/1</td>\n</tr>\n<tr>\n<td>optimize/0</td>\n</tr>\n<tr>\n<td>public/1</td>\n</tr>\n<tr>\n<td>reset/0</td>\n</tr>\n<tr>\n<td>reset/1</td>\n</tr>\n<tr>\n<td>restore/1</td>\n</tr>\n<tr>\n<td>save/1</td>\n</tr>\n<tr>\n<td>save/2</td>\n</tr>\n<tr>\n<td>when_error/2</td>\n</tr>\n<tr>\n<td>Part 4 - Operational Features Of Prolog++</td>\n</tr>\n<tr>\n<td>Chapter 12 - Reacting To Class Instances</td>\n</tr>\n<tr>\n<td>When A New Instance Is Created</td>\n</tr>\n<tr>\n<td>When An Existing Instance Is Deleted</td>\n</tr>\n<tr>\n<td>Chapter 13 - Reacting To Attribute Values</td>\n</tr>\n<tr>\n<td>Invalid Attribute Values</td>\n</tr>\n<tr>\n<td>Reacting To New Attribute Values</td>\n</tr>\n<tr>\n<td>Chapter 14 - Exception Handling</td>\n</tr>\n<tr>\n<td>Part 5 Appendices</td>\n</tr>\n<tr>\n<td>Appendix A - Formal Syntax Of Prolog++</td>\n</tr>\n<tr>\n<td>How To Read The Grammar Rules</td>\n</tr>\n<tr>\n<td>Class</td>\n</tr>\n<tr>\n<td>Declarations</td>\n</tr>\n<tr>\n<td>Categories Declaration</td>\n</tr>\n<tr>\n<td>Inherits Declaration</td>\n</tr>\n<tr>\n<td>Parts Declaration</td>\n</tr>\n<tr>\n<td>Attributes Declaration</td>\n</tr>\n<tr>\n<td>Methods Declaration</td>\n</tr>\n<tr>\n<td>Definitions</td>\n</tr>\n<tr>\n<td>Functional Method Definition</td>\n</tr>\n<tr>\n<td>Procedural Method Definition</td>\n</tr>\n<tr>\n<td>Message Handler Definiens</td>\n</tr>\n<tr>\n<td>Error Handler Definiens</td>\n</tr>\n<tr>\n<td>Constraint Handler Definiens</td>\n</tr>\n</tbody>\n</table>\nContents\n\nAssignment Handler Definiens ........................................... 149\nCreate Handler Definiens .............................................. 149\nDelete Handler Definiens .............................................. 150\nProlog++ Statements ......................................................... 150\nControl ........................................................................... 151\nAttribute Assignment ..................................................... 151\nNoisy Assignment Operators ......................................... 152\nQuiet Assignment Operators ......................................... 152\nProcedural Message Passing .......................................... 152\nProcedural Message ...................................................... 154\nRemote Message Receiver .......................................... 154\nProlog++ Terms ............................................................... 154\nContext .......................................................................... 156\nFunctional Message ...................................................... 157\nStructural Link .............................................................. 157\nIs-A Link ......................................................................... 158\nPart-Of Link ................................................................. 158\nAppendix B - Shorthand Declarations ............................ 160\nAppendix C - Prolog++ Operators .................................. 161\nAppendix D - Summary Of \"prolog_plus_plus\" .................. 165\nAppendix E - Benchmark ................................................ 165\nThe Prolog Program ....................................................... 165\nThe Prolog++ Classes .................................................... 165\nBenchmark Results ....................................................... 167\nAppendix F - Glossary ...................................................... 169\nIndex ............................................................................ 173\nThis page is intentionally blank\nWelcome\n\nWelcome to this latest version of Prolog++, a state-of-the-art development system based on the best features from two advanced technologies, artificial intelligence (AI) and object-oriented programming systems (OOPS).\n\nThe relative strengths of Prolog and object systems are complimentary, which gives rise to a “dovetail” join rather than a “bolt-on”. The underlying philosophy of the two technologies have a similarly good fit; the ideas of type-free programming and polymorphism fit well as do the ideas of dynamic data structures and run-time generation of new objects.\n\nAll in all this gives rise to an exciting and powerful product, Prolog++. We hope you enjoy using it and wish you much success in building your applications.\n\nWe at LPA are always keen to hear from our customers and users of our products, so if you have any criticisms, bug reports, comments on the manual, grumbles, congratulations, etc. you know what to do.\n\nClive Spenser,\nLPA Product Development Team,\nStudio 4,\nThe Royal Victoria Patriotic Building (RVPB),\nTrinity Road,\nLondon, SW18 3SX\n\nTel +44 181-871-2016\nFax +44 181-874-0449\nemail support@lpa.co.uk\nAn Object-Oriented View Of Prolog++\n\nThe following diagram illustrates the relationship between Prolog++ and other programming languages.\n\nProgramming languages can be roughly split between the traditional approach which describes a program as a collection of algorithms and procedures which manipulate data, and the object-oriented approach which maps data directly onto objects which have the capability of communicating with each other.\n\nThe traditional approach can be further classified into procedural languages, such as Cobol, C, etc., and declarative languages such as Prolog. Each approach has its benefits and its drawbacks.\n\nOne of the first object-oriented languages to be developed was Smalltalk, in which everything (including all integers, reals and identifiers) is considered to be an object. The emerging languages, such as C++, combine features of traditional languages with the object-oriented approach. One might say that C++ inherits characteristics of both approaches.\n\nProlog++ follows the lead of C++, but whereas C++ combines a procedural language with OOPS, Prolog++ combines a declarative language with OOPS. One might say that Prolog++ inherits the problem solving and database characteristics of Prolog, and also inherits the sound methodology of an OOPS approach.\nHow To Use This Manual\nThe basic layout of this manual has 4 parts :-\n\nPart 1 Chapters 1-3 A general discussion about OOPS\nPart 2 Chapters 4-8 Case studies using Prolog++\nPart 3 Chapters 9-11 Technical specification of Prolog++\nPart 4 Chapters 12-17 Operational features of Prolog++\n\nThis manual is intended to have a dual rôle, both as a general introduction to OOPS and Prolog++, and as a reference manual for the Prolog++ implementation.\n\nThe following sections outline how to read each of the major divisions. The accompanying diagrams illustrate the inter-dependency of chapters, using a pictorial convention :-\n\n- Chapter \\( N \\) of this manual.\n- Additional reading material.\n- Advised route through the chapters.\n- Recommended material before reading a chapter of the manual.\n- Supplementary material.\nPart 1 Object-Oriented Programming Systems\n\nAny book on Prolog\n\n1 OOPS\n\nAny book on OOPS\n\n2 Logic-Based OOPS\n\n3 Prolog++\n\nThe chapters of this part are intended to be read sequentially, starting at chapter 1. Those readers who are already familiar with the general concepts of OOPS can begin at chapter 2, and those who have an understanding of both Prolog and OOPS might like to go straight to chapter 3.\n\nThe reader is advised to accompany this manual with any general book on OOPS, although this is not strictly necessary. Before reading chapter 2, however, a basic understanding of logic-based languages, and Prolog in particular, is strongly recommended.\n\nEach chapter can be thought of as a specialization of the previous chapter, starting at general concepts (chapter 1), through more specific, logic-based concepts (chapter 2) and finally to Prolog++ (chapter 3), an actual instance of OOPS.\nPart 2 Case Studies\n\nThe case studies of part 2 cover four different topics. It is not necessary to be familiar with any of these topics, although a basic understanding will assist the reader in the formulation of each problem.\n\nAt this stage, no details about the technical specification of Prolog++ have been given. The reader may either accept faithfully the solutions given, or refer to the technical part which follows for clarification of particular points.\n\nPart 3 Technical Specification\n\nThe technical part consists of three chapters, consisting of a specification of the language, the two pre-defined classes and the interface between Prolog and Prolog++.\n\nPart 4 Operational Features\n\nThe chapters of this part can be read in any order whatsoever, since they cover completely different topics. This part should only be read after the technical specification of Prolog++ given in part 3.\n\nThe chapters on optimization, saving and loading reference certain aspects of the underlying Prolog implementation.\nPart 1 - Object-Oriented Programming Systems\nChapter 1 - General Concepts Of OOPS\n\nThe object-oriented approach to computer programming has its own terminology. In this chapter we list the key concepts, and explain the ideas they represent.\n\nDefinitions\nWe start by looking at what the terminology surrounding OOPS actually means. These definitions, whilst generally true of most OOPS environments, are not intended as the only interpretation.\n\nAbstraction\nAbstraction is the process of generating an abstract or outline of a complicated entity.\n\nEncapsulation\nEncapsulation is the process of gathering together and isolating, within its outline, all aspects of an entity.\n\nClass\nIn OOPS, the process of encapsulation results in the formation of classes. All code and data representing an entity is found within a unique structure, namely its class.\n\nClass Hierarchy\nA class hierarchy refers to the connecting together of classes, in which more general classes appear towards the top of the hierarchy and more specific classes towards the bottom.\n\nInheritance\nInheritance is the ability of a class to receive some of its characteristics from more general classes which appear higher up the class hierarchy.\n\nInstance\nAn instance refers to an individual incarnation of a class. A class instance is sometimes called an object.\nMessage\nA message is the means by which instances communicate with each other.\n\nAbstract\nA class abstract defines the range of messages which an instance of that class can handle.\n\nMethod\nA method is a procedure whose purpose is to handle messages sent to instances of the class in which it is defined, or a more specific class lower down the class hierarchy.\n\nAttribute\nA class attribute corresponds to a specific characteristic of the entity which the class represents.\n\nPublic\nA public attribute or method is one to which all other classes have access.\n\nPrivate\nA private attribute or method is one that may only be accessed by the class in which it is defined.\n\nPolymorphism\nPolymorphism is the ability to define the same method in different classes.\n\nOOPS\nOOPS is based on the use of separate entities which communicate with each other to form a system.\n\nThere are two main aspects to OOPS: organisation and communication.\n\nOrganisation is accomplished through class hierarchies and communication is carried out through the sending of messages between instances of those classes.\n\nConventional programming generally concentrates on procedures and procedure calls. Data is somewhat secondary and is passed around as arguments to procedures. In OOPS classes have both the procedures (methods) and the data (attributes) held locally. These have equal status within the class.\n\n16 Prolog++ Reference\nClasses and Instances\nA class is a template which defines the general characteristics of its instances and those of any of its sub-classes, sub-sub-classes, etc..\n\nA class contains methods for handling messages sent to instances of that class and attributes for storing data. The methods of a class handle the range of messages an instance of that class is capable of responding to.\n\nA class does not have access to the internal mechanisms of other classes which can only be accessed through the sending of messages. Classes do not need to have all of their methods available publicly. Some methods and attributes can be private. The abstract of an class contains all the names of its public methods and attributes. This provides a complete list of all the external messages that an instance can handle.\n\nAbstraction\nAbstraction in OOPS refers to the process by which the definition of a class is summarised into a few key concepts.\n\nData abstraction is a definition of the interface to a data structure.\n\nWhen using classes it is not necessary for us to know their mechanics, only their key concepts and intended usage. In this way the key concepts can be used as an interface to the classes allowing them to be re-used, like building blocks, in different programs.\n\nTo illustrate this, consider a knight and a bishop from the game of chess.\n\nWe know that they both have similar characteristics, such as how they move, what shape they are, what their initial positions are, etc.. The differences between these two chess pieces lie in the actual description of how they move, what shape they are, what their initial positions are and so on.\n\nFor example, to define the moves of a knight and a bishop, we could state:\n\nTo move a knight, move it two squares horizontally or vertically in either direction then one square vertically or horizontally in either direction as long as the resultant position is legal.\n\nand:\n\nTo move a bishop, move it in any diagonal direction any number of squares as long as the resultant position is legal.\n\nWhen moving one of the pieces it is natural for us to want to say:\n\n“Move the knight or the bishop (I do not care how you do it)”\n\nas opposed to having to say:\n“Move the knight two squares horizontally or vertically in any direction then one square vertically or horizontally in any direction...”.\n\nThe diagram above shows the knight and bishop pieces, with the procedure for moving each contained in the box of text. On the right of the diagram are the abstracts of the pieces, which define the range of messages to which the piece may react.\n\nThe pieces are actually moved by simply telling them to move. The capability of being able to move the knight, without having to be concerned about the actual mechanics of how a knight moves, allows the use of a more modular or distributed approach to programming.\nWe can think of the inner mechanisms of the pieces as ‘black boxes’, which allows us to use the objects by just referring to their abstract.\n\nAnother facet of abstraction is in the construction of class hierarchies.\n\nWithin the definitions of move for both the knight and the bishop we referred to the concept of a legal position. We can abstract this concept of a legal position, and define it in a more general class called chesspiece. In the chesspiece class we place all the concepts common to any chesspiece, not just knights and bishops.\n\nWe would then say that both the knight and bishop were specialisations of the chesspiece class and these would then share the definition of a legal position.\n\nOne advantage of abstraction is that it allows classes to be easily re-used in different programs. This is because classes are self-contained entities, and all that needs to be known about a class are the abstractions of its internal mechanisms.\n\nFor example, the knight may be used both in a chess program and in a ‘knights tour’ program. We only need to know the names of the methods the knight uses, such as move etc.\n\nEncapsulation\n\nEncapsulation isolates all the aspects of a class within its outline. This protects the internal routines of the class and thus guarantees its functionality. Through encapsulation the interface between one class and another is unambiguous.\n\nMessage Passing\n\nClass instances communicate in OOPS by sending messages. When a message is received by an instance it must have the appropriate message handler (method) to deal with the message.\n\nMethods generally take the form of a set of procedures, defined at the class level, which are invoked by the name of the message.\n\nWe talked earlier about telling a knight or a bishop to move. Such a directive would be implemented in an object-oriented system by sending the message move to either a specific knight or a specific bishop.\n\nPolymorphism\n\nPolymorphism literally means ‘many forms’ and refers to the ability to use a single name for different methods in different classes. This allows us to send the same message to several different objects, each having their own set of methods for handling the message.\n\nAs an example, we saw earlier that the same message, move, could be used for two different chesspieces the knight and bishop, to trigger two different reactions.\n\nPolymorphism is an extremely powerful tool for generalising the name of a task across many different types of class, each having their own definition of that task.\nInheritance\n\nWe have seen that a class may be defined as part of a class hierarchy, and that attributes and methods may filter down to other classes through the hierarchy.\n\nThe mechanism for this distribution of information is inheritance.\n\nInheritance has two advantages. Firstly, it avoids unnecessary duplication of information. Secondly, because the code for a class is re-used by its sub-classes, the integrity of the system is easier to maintain. Once a method has been shown to be reliable that reliability is propagated down through the class hierarchy.\n\nAn example of inheritance is the shared definitions of the knight and the bishop, such as the definition of legal position, which they both inherit from the chesspiece class.\n\nSingular Inheritance\n\nSingular inheritance corresponds to a property of the class hierarchy in which each class is limited to at most one parent class. This property guarantees that the structure is a strict hierarchy, with a unique path (or branch) between any two connected instances.\n\n![Diagram of a singular inheritance class hierarchy]\n\nThis diagram shows a singular inheritance class hierarchy, where each instance is represented by a circle and inheritance links are shown as dark lines.\n\nEach class has at most one parent class.\n\nWhen a message is sent to an instance whose class definition does not contain the appropriate message handler, a search is made of the hierarchy. The search begins at the instance's class where the message was originally sent and proceeds upwards until a class is found that can handle the message.\nMultiple Inheritance\n\nMultiple inheritance relaxes the parenthood constraint to allow for multiple parents of a class. Multiple inheritance leads to a tangled hierarchy (or directed, acyclic graph) rather than a strict hierarchy.\n\n![Diagram of multiple inheritance]\n\nThis diagram shows multiple inheritance, where a given class may have one or more parents.\n\nBinding\n\nBinding is the mechanism by which messages are associated with their handlers. In traditional programming languages a procedure call is associated with a procedure definition simply by name, and the link between them forged by the compiler. In an OOPS world with polymorphism there is a binding process to establishes the links since the same message can potentially be handled by several alternative handlers.\n\nEarly Binding\n\nThe early binding of a message to a particular handler is performed by the OOPS compiler, and corresponds exactly to the compiling techniques of traditional languages.\n\nLate Binding\n\nThe late binding of a message to a particular handler is performed at run-time, and is determined by the exact context in which the message is sent.\n\nData-Driven Programming\n\nThe paradigm of data-driven programming is a relatively new phenomenon. Traditional languages such as C, Pascal and even Prolog view a program as a collection of procedures and statements. The flow of control can be completely determined by the way procedures, and to some extent program statements, call one another. With data-driven programming, however, this scenario is turned on its head.\n\nA collection of data-driven procedures, called daemons, may be written which interrupt the main process. These are not connected to each other and, as with interrupts, there is no direct flow of control between them. Instead, daemons lie dormant and are only activated by certain events occurring. Of course, the execution of a daemon may itself cause\nanother event which triggers another daemon, possibly resulting in a cascade of daemons being triggered.\n\nFor example, suppose we have developed an object system which describes the logical relationship between chess pieces and the chess board. It will involve such things as the initial configuration of the board, which moves are legal and perhaps some game playing skills. This logical view of the game of chess can then be integrated into a graphics system by introducing daemons which react to the movement of pieces. The daemons will be triggered when a logical move takes place, and will drive graphical operations to reflect such moves on a screen.\nChapter 2 - A Logical Approach To OOPS\n\nHaving looked at the terminology that surrounds OOPS, we will now discuss how a logical approach to OOPS is beneficial.\n\nProlog as a Logic-Based Language\n\nProlog is a declarative language. This means that the formal definition or declaration of a problem may be used as a functional program to solve that problem. In Prolog we declare the logical relationships of a given problem domain rather than state a step-by-step procedural recipe for solving the problem. This is useful as often we know various aspects of the problem but very little about how to find a solution. Prolog will attempt to find a solution for us given the information about the problem.\n\nThe way Prolog does this is by using a built-in inference engine, which automatically infers the solution to a given query using the facts and rules as defined in the program.\n\nProlog programs consist of facts and rules, which are referred to as clauses. A fact consists of a single assertion with no conditions: a fact is always true. A rule consists of a goal, whose truth is dependent upon a set of conditions or sub-goals. The goal of a rule is referred to as its head and the sub-goals as its body.\n\nProlog attempts to prove a goal by using its backward chaining inference engine to match the initial goal with either a known fact or the head of a rule. If the goal is matched with a known fact the goal is proven. If the goal is matched with the head of a rule the original goal is then replaced with the sub-goals which form the body of the rule. Prolog then attempts to prove, in the same way, each of these sub-goals in turn.\n\nAlthough Prolog programs are thought of as declarative they can also have a procedural reading. Prolog is versatile: there is a style of Prolog programming which mimics the conventional procedural approach, but with less emphasis on the actual assignment statements.\n\nProlog as a logic programming language has a sound theoretical basis, being modelled on the first-order predicate calculus. This means that theoretically a Prolog program, which may be read as a set of axioms and theorems, contains the possibility of being proven consistent or inconsistent, regardless of the implementation. In this way Prolog can be thought of as an automated theorem prover.\n\nVariable Types\n\nA feature of Prolog is its use of type free variables which can represent widely different data structures. This allows any variable in a clause to represent a number, a string, a list of numbers, a list of strings, a list of strings and numbers etc. Prolog variables can even be used to represent clauses. This last use of variables leads to a technique called meta-programming, where the clauses in one part of a program can manipulate other clauses as data. This 'meta-level' ability is one reason why Prolog has been widely used in the realm of expert systems.\n**Data Structures**\n\nAnother feature of Prolog is its ability to allow the dynamic assertion and retraction of rules and facts. This makes the Prolog rule and data base truly dynamic at run-time. This is essential for “learning systems” and other applications involving the introduction of new concepts, rules or facts at run-time.\n\nMemory is dynamically allocated and deallocated at run-time. The deallocation is automatically done by a built-in garbage collector. The programmer does not have to be concerned with the implementation, maintenance and bookkeeping normally associated with the creation and destruction of complex dynamic data structures and is freed to concentrate on stating the logic of the problem.\n\n**How OOPS Can Benefit From Prolog**\n\nThere are a number of advantages gained by using Prolog as a basis for an object-oriented language.\n\nAs discussed earlier in this chapter, Prolog is a type free language. This allows greater freedom for the programmer than a typed language, leading to an increase in both productivity and creativity.\n\nAll data structures in Prolog are dynamic. The creation and garbage collection of data structures is automatic. A Prolog-based OOPS will reflect this by allowing truly dynamic class hierarchies.\n\nFor example, consider a program which establishes animal taxonomies. The common features of animals may be abstracted into general classes and particular animals can then be classified according to those classes. In a Prolog-based OOPS not only can we dynamically add classes to a class hierarchy, we can dynamically augment classes that have already been established. This means that when a new characteristic is found for an existing animal, it can immediately be added to the class structure of that animal at run-time. This is not easily achieved in other systems.\nThe dovetailing of these two technologies leads to a very powerful and expressive system:\n\n![Diagram]\n\n**How OOPS Can Enhance Prolog**\n\nThe introduction of an OOPS methodology to Prolog can be beneficial in the following ways.\n\nAn OOPS provides a clear and intuitive structure for programs, in the form of class hierarchies. The one-to-one mapping between entities in the problem domain and classes in the program allows for a more easily understood program structure. In contrast, traditional module systems are a means of organising code for ease of development, and their structure does not necessarily correspond to the problem at hand.\n\nProlog imposes very few restrictions on the structure and organisation of a program. This is fine for small scale programs, but can lead to problems when constructing large applications. The onus is on the programmer to impose some discipline for organising and managing their code. The imposition of a class hierarchy leads to more efficient and easily manageable program structures.\n\nAn class has a well-defined interface which corresponds to its abstract or outline. Since this outline is a direct summary of an entity, knowing the entity allows the interface to be easily understood. This assists in the modularity of programs and the use of classes as “building blocks”. Libraries of adaptable classes may then be created which can easily be integrated into larger applications.\nSome Prolog-Based OOPS\n\nThe integration of Prolog and OOPS has attracted much interest within the academic community over the past few years, and many prototype systems have been developed. In addition, this basic research is now showing itself in the commercial marketplace. Two examples of the integration of Prolog and OOPS are presented here.\n\nLOS\n\nLOS (Logic and Instance System) has been developed at Imperial College, London by F.G. McCabe. It is a very expressive system, incorporating ideas from Prolog, OOPS and Lisp. It differs from Prolog++ in three major areas:\n\n- There are two, quite different inheritance mechanisms which can be used in LOS. The first is akin to the inheritance mechanism of Prolog++, and is called overriding inheritance. The second mechanism allows methods to be inherited in addition to any local statements. This means that a method is actually defined by the union of all statements in the class hierarchy for that method.\n\n For example, a class hierarchy for fault diagnosis will implicitly state that the possible faults are the union of all faults at all levels.\n\n- An instance in LOS is not limited to a name alone, but may include parameters which are available to all the methods defined within the instance. These parameterized objects are referred to as class templates.\n\n For example, a train may have various attributes, such as speed and power rating, which are included as parameters of the train class template. A particular train, such as the Flying Scotsman, will be declared as a sub-class of train with particular values for speed and power.\n\n- There are no run-time objects in LOS, and no dynamic attribute values. To some extent, the parameters of class templates behave like attribute values.\n\nLAP\n\nLAP is a commercial product from Elsa software which integrates OOPS into Prolog by a suite of built-in routines. There is no additional programming language to learn, as LAP remains completely within the boundaries of Prolog.\n\nThe OOPS library of LAP is very extensive, with many routines for manipulating objects, methods and instances. Methods in LAP are divided into prefix statements, body statements and suffix statements, which is a very powerful feature for certain problem domains.\n\nIn addition to the basic library, Elsa have built an object-oriented environment for the development of LAP programs.\nChapter 3 - The Prolog++ Approach To OOPS\n\nHere we discuss the way Prolog++ relates to the definition of OOPS found in chapter 1.\n\nOOPS Features Of Prolog++\nProlog++ exhibits all the features of OOPS mentioned in the preceding chapters. They are:\n\n- Abstraction\n- Encapsulation\n- Polymorphism\n- Message Passing\n- Inheritance\n- Singular\n- Multiple\n\nClass Hierarchies And Inheritance\nClass hierarchies are implemented by denoting within an class who its parents are. The inheritance of methods and attributes is governed by this relationship. Prolog++ supports multiple inheritance by multiple declarations of parenthood.\n\nPolymorphism And Message Broadcasting\nProlog++ supports the use of different methods in different classes which can handle the same message. This follows the common view of polymorphism.\n\nProlog++ provides the ability to broadcast messages in the following ways:\n\n- A single message to a group of instances.\n- A group of messages to a single instance.\n- A group of messages to a group of instances.\nEncapsulation And Abstraction\n\nClass definitions in Prolog++ are delimited by key words for their beginning and ending. All the methods and attributes within these two statements are encapsulated.\n\nThe name of the class and the names of any public methods and attributes form the abstract of that class.\n\nData-Driven Programming\n\nThe paradigm of data-driven programming is expressed in Prolog++ by the use of specific methods. Within Prolog++ there are four kinds of events which may cause a handler to be invoked. These are:\n\n- create a new class instance\n- delete an existing class instance\n- assign a new value to a class/instance attribute\n- raise a program exception\n\nThe Inheritance Mechanism Of Prolog++\n\nWhenever a message is sent to an instance (or indeed a class itself) the Prolog++ system determines a single location which has the capability of handling that message. Often the location will be the target class itself. Once the location has been determined the system commits itself to sending the message there and nowhere else. The method of determining locations which can actually handle messages is called the inheritance mechanism.\n\nThe inheritance mechanism of Prolog++ is based upon the same searching principles as the underlying Prolog system. This search is a branch-first, left-to-right traversal of the class hierarchy starting at the instance's class to which the message was originally sent.\n\nTo illustrate the searching involved in the inheritance mechanism we shall consider two example hierarchies. The first is a strict hierarchy representing singular inheritance, and the second is a lattice representing multiple inheritance.\n\nSingular Inheritance\n\nIn the following diagram the methods α, β, γ and δ are defined in various objects A, B, C1 and C2.\nThe following table shows where messages will actually be handled. For example, select message $\\gamma$ from the left-hand column and class C1 from the top-most row. Their intersection in the table, namely B, is the class where the message $\\gamma$ will actually be handled. An empty cell in the table indicates that the message cannot be handled when sent to instances of that class.\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>A</th>\n<th>B</th>\n<th>C1</th>\n<th>C2</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>$\\alpha$</td>\n<td></td>\n<td></td>\n<td>C1</td>\n<td>C2</td>\n</tr>\n<tr>\n<td>$\\beta$</td>\n<td></td>\n<td></td>\n<td>C1</td>\n<td></td>\n</tr>\n<tr>\n<td>$\\gamma$</td>\n<td>A</td>\n<td>B</td>\n<td>B</td>\n<td>B</td>\n</tr>\n<tr>\n<td>$\\delta$</td>\n<td>A</td>\n<td>A</td>\n<td>A</td>\n<td>C2</td>\n</tr>\n</tbody>\n</table>\n\n**Multiple Inheritance**\n\nIn the following diagram the methods $\\alpha$, $\\beta$, $\\gamma$ and $\\delta$ are defined in various objects A1, A2, B1, B2 and C. The important links are from B1 and B2 down to C. Class B1 is the first parent of C and class B2 is the second parent of C. This ordering is crucial for determining inheritance.\nThe following table shows where messages sent will actually be handled. For example, select message \\( \\gamma \\) from the left-hand column and class C from the top-most row. Their intersection in the table, namely A1, is the class where the message \\( \\gamma \\) will actually be handled. An empty cell in the table indicates that the message cannot be handled when sent to any instances of that class.\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>A1</th>\n<th>A2</th>\n<th>B1</th>\n<th>B2</th>\n<th>C</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>( \\alpha )</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td>C</td>\n</tr>\n<tr>\n<td>( \\beta )</td>\n<td>B1</td>\n<td>B2</td>\n<td>B1</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>( \\gamma )</td>\n<td>A1</td>\n<td>A1</td>\n<td>B2</td>\n<td>A1</td>\n<td></td>\n</tr>\n<tr>\n<td>( \\delta )</td>\n<td>A2</td>\n<td>A2</td>\n<td>A2</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**The Binding Process**\n\nProlog++ binds messages to handlers either at compile-time (early) or at run-time (late), depending upon whether or not the message can be handled locally by the class in which it textually occurs.\n\nTo illustrate the difference between early and late bindings consider the following definitions for classes *alpha* and *beta*.\n\n```prolog\nclass alpha .\n\nprint_early :-\n print_header,\n print_contents,\n print_footer.\n\nprint_late :-\n print_header,\n self <- print_contents,\n print_footer.\n\nprint_contents :-\n ...\nend alpha.\n\nclass beta .\n\ninherit alpha .\n\nprint_contents :-\n ...\n```\n\n30 Prolog++ Reference\nEarly Binding\n\nEarly binding automatically occurs for local messages whenever there is a corresponding local handler. An early binding is forged at compile-time which greatly improves the efficiency of the resulting code by avoiding the search for a handler.\n\nFor example, the message print_contents in the definition of print_early in class alpha will be bound to the corresponding method also found in class alpha.\n\nLate Binding\n\nLate bindings between a message and a class capable of handling it are forged at run-time whenever no local link can be found and for all messages which are explicitly sent to an object. It takes the form of a search up through the is-a hierarchy of classes starting at the class of the message receiver.\n\nFor example, the messages print_header and print_footer in the definitions of print_early and print_late in class alpha will be bound at run-time according to the context in which they are sent. That is, the binding is determined by the object which originally received the print_early or print_late message.\n\nForced Late Binding\n\nIf you wish to avoid an early binding (and thus fool the compiler) send the message explicitly to the self variable. When this is stated in the code a late binding will always be performed at run-time even if there is a local handler for that message.\n\nFor example, the definitions of print_early and print_late in class alpha only differ in the way they send the message print_contents. The method print_late forces the message to be bound at run-time by explicitly sending it to the self variable.\n\nThe message print_early for an instance of beta will use the definition of print_contents found in alpha, whereas the message print_late for a similar instance will use the definition of print_contents found in beta itself.\n\nIf the definition of print_contents were removed from class alpha then the two calls would be equivalent since the compiler would not be capable of an early binding!\nHow Prolog++ Benefits From Prolog\n\nProlog++ inherits from Prolog the ability to use dynamic data structures; this extends to include classes and instances.\n\nThe variables used within Prolog++, being type-free, can be used to represent widely different data structures.\n\nIn addition to these, Prolog++ may be fully integrated with standard Prolog programs. Each Prolog++ class has access to all Prolog predicates, whether system-defined or user-defined.\n\nThis allows Prolog++ to inherit all the capabilities of a fully developed Prolog environment.\n\nHow Prolog++ Enhances Prolog\n\nPrograms may be developed using Prolog++ which augment standard Prolog in the following ways.\n\nThe ability to define a class hierarchy allows the programmer to partition Prolog programs into dynamic modules which closely resemble the structure of the problem domain.\n\nEach class within Prolog++ also has a clearly defined interface formed by the names of its methods. The ability to define classes whose interface corresponds to their function is also of use when trying to model the problem domain.\n\nThe ability to have a close resemblance between a class, its interface and the problem domain enables the interfaces to the classes to be easily understood. This coupled with the encapsulation of the classes into packages of code and data allows Prolog++ programs to be re-used like building blocks.\n\nData-Driven programming is supported by allowing daemons to be attached to crucial events. The mechanism for trapping events is incorporated in the Prolog++ engine itself and does not need to be explicitly handled by the user.\n\nProlog++ And Smalltalk\n\nThis section compares Prolog++ with Smalltalk.\n\nGeneral\n\nSmalltalk is an object-oriented procedural language.\n\nSmalltalk is generally acknowledged as the first major implementation of the OOPS paradigm.\n\nSmalltalk was derived at Xerox's Palo Alto Research Centre, by a process of evolution from Simula-67, a language designed for the implementation of simulations.\nEnvironment\n\nSmalltalk is usually used in a graphical environment tailored specifically for Smalltalk development. This environment usually includes - mouse handling, windows, menus, editors, browsers etc.\n\nMemory management is automatically provided by the system in the form of garbage collection of objects.\n\nProlog++ provides all of this through the underlying Prolog system.\n\nClasses\n\nA class defines the behaviour of similar objects by specifying their structure and functionality; the data they represent and the methods available for responding to received messages. The class concept in Smalltalk is distinguished from an object in general by virtue of the class definition messages by which a class is defined. These messages are sent to the classes' superclass with its specification as arguments.\n\nAlso classes are global structures in that any class can be referenced by name within any instance. In practice this means that objects of any class can be created anywhere.\n\nAs classes in Smalltalk are objects, the metaclass concept is used to describe the general class behaviour. Thus every class belongs to its own unique class called a metaclass which determines the messages to which the class can respond. The general behaviour of metaclasses is described in the class MetaClass. All instances of MetaClass (i.e. metaclasses) have the superclass Class. The methods for the class definition messages are defined in Class.\n\nThis is called classtrophobia!!!!\n\nMethods and Messages\n\nA message in Smalltalk is simply the identifier for an associated method defined by the class of the instance that receives the message. A message, in a similar fashion to a function, always returns an instance of some sort. In Smalltalk messages may take arguments.\n\nMessages may be cascaded.\n\nA cascaded message is a series of messages sent to one receiver instance.\n\nProlog++ can also cascade messages, it can also broadcast messages to several instances.\n\nThere are several types of message:\n\nSmalltalk distinguishes three types of message; unary, binary, keyword (n-ary). These are distinguished by arity, precedence and syntax.\n\nProlog++ does not distinguish between messages according to their arity (unary, binary, ternary etc.). A message may contain any number of arguments.\nObjects\n\nIn Smalltalk everything is an instance.\n\nAn object's internal variables are termed instance variables; these will also contain objects. For example an instance of the class “complex numbers” may have the following values for its instance variables:\n\n real = 1.0\n imaginary = 0.4.\n\nThe instance variables are defined in the object's class definition.\n\nProlog++ also has the concept of instance variables. They are called attributes.\n\nInheritance\n\nSmalltalk does not implement multiple inheritance - everything inherits from the root instance, 'Object'. This form of inheritance is sometimes called 'tree inheritance' for obvious reasons.\n\nProlog++ supports multiple inheritance, which is a superset of tree inheritance.\n\nEncapsulation\n\nAn instance of a class is encapsulated by the data-abstraction for that class. All instance variables are private to that instance and can only be accessed via the class protocol.\n\nIn Prolog++ an instance of a class is similarly encapsulated by the data-abstraction for that class.\n\nPolymorphism\n\nMessages and methods are genuinely polymorphic, i.e. the same message for different objects may have different methods depending on the instance.\n\nData Abstraction\n\nData abstraction is organised via the class hierarchy.\n\nProlog++ And C++\n\nThe version of C++ referred to here is 2.0 from AT&T.\n\nGeneral\n\nC++ was developed, and is still being developed, by Bjarne Stroustrup at AT&T Bell laboratories. It has become a major systems language as an enhancement of C.\nC++ is a more traditional batch compiled language, and to that extent it is a lot less flexible than either Smalltalk or Prolog++.\n\nThe C++ language is, like Prolog++, an object-oriented extension of an already existing language. C++ takes the C struct keyword, which is used for user defined data types, and extends and enhances it to provide the basic object-oriented mechanisms. Struct is retained, but an ability to associate functionality with the data type is added. A further more important construct, namely the class, is also provided. The struct is a special case of a class with no protected or private sections.\n\nBy this means C++ provides the C language with the various bits and pieces which are generally acknowledged to be object-oriented.\n\nC++ is a strongly typed language. This has important implications for implementation and prototyping techniques. Prolog++ is not strongly typed: this aids the speed of development and prototyping.\n\nC++ is a looser (compared to Smalltalk) object-oriented system in that the programmer is not compelled to use class methodology. She may still write in normal (ANSI) C. Prolog++, via Prolog, also provides this escape from being straight-jacketed into the OOPS paradigm. This is a distinct advantage over Smalltalk as some problems do not naturally fit within the OOPS paradigm.\n\nA system devised in C++ tends to be more rigid than Prolog++ or Smalltalk.\n\nC++ has a major problem in the area of exception handling. It is not defined at all except insofar as inheriting C's primitive approach. These problems come to light most vividly when using dynamic objects and heap manipulation.\n\nEnvironment\n\nVarious commercial products are available for the development of C++ programs.\n\nMemory managment is left to the user.\n\nClasses\n\nThe class in C++ is the main vehicle of data-abstraction. It encapsulates and hides the underlying data structure. C++ has within the class construct the notions of private, public and protected, by which it controls the access to data and methods. Private data and methods are only available to member functions defined within the scope of the class. Protected data and methods are available only to the class and its derived classes via inheritance. Public data and methods are available to all. The default is for data and methods to be private. The private access can be overridden by the friend keyword, which can name functions as friends to the class.\n\nMethods and Messages\n\nA message in C++ is the name of a method passed to an instance. A message corresponds to a function defined in the class template of that instance. These are called member functions in C++. Generally definitions within a class are termed class members.\nMember functions of a class with the same name as the class (say for class foo - foo()) are termed constructor functions. Member functions with the same name as the class preceded by a tilde (~foo()) are termed destructor functions. Constructors generally correspond to class methods in Smalltalk. While destructors simply destroy objects when they go out of scope.\n\nIn C++ there are two types of method, normal functions and in-line functions. In-line functions are intended to replace parameterized macros, which because of their inherent lack of argument typing are considered 'unsafe'. C++ also has two forms of method determination. By default, methods to answer messages are determined by the compiler and hard-wired into the instance code. A virtual function, however, is determined at run-time. The run-time system decides which function to field dependent upon the type of the receiving instance. This last is usually called late-binding. Late-binding is fundamental to all object-oriented systems. Both function and in-line methods let the user create more efficient code.\n\nProlog++ has an advantage in this respect in that the underlying system has late-binding at its core in the form of unification.\n\nEach message evokes one function call only. Cascading must be done manually by the programmer.\n\n**Objects**\n\nEach instance of a given class has its own copy of all the data defined by the class.\n\nThe static declarator overrides this inheritance and provides a means for class variables, as in Smalltalk (i.e. a single variable whose value is inherited by all objects of that class).\n\nObjects may be static - created at compile time; or dynamic - created at runtime. The C++ language extends the C language by providing the functions, new and delete, which allocate and free heap space for the ease of use of dynamic objects (as opposed to malloc etc.).\n\n**Inheritance**\n\nAs of version 2.0 C++ supports multiple inheritance.\n\n**Encapsulation**\n\nThe C++ language provides for encapsulation via the data definition constructs: struct and class. In C++, for efficiencies sake, this mechanism may be overridden in various ways.\n\n**Polymorphism**\n\nMember functions of a given class can be overloaded. The overloaded member functions are distinguished by the types of their arguments.\nOperator overloading\n\nNearly all the operators in C++ may be overloaded. What this means is that any operator, such as ‘+’ say, can be given a new functionality within a given class. The precedence and associativity is, however, immutable. Prolog++ also provides this convenience via the underlying Prolog system. In Prolog an operator is purely syntactic, being the functor of a relation.\n\nData Abstraction\n\nData abstraction in C++ is organised by the class hierarchy.\n\nC++ offers a variety of data protection: public, private or protected. By default, data is private to a class definition. This data protection may be overridden by declaring friend functions.\nPart 2 - Case Studies In Prolog++\nChapter 4 - Introduction To The Case Studies\n\nThese case studies are intended to introduce both the language of Prolog++ and some of its salient features. The reader may either accept the solutions given or refer to the following technical part for clarification of particular points.\n\nAs a brief introduction to some of the notation used within Prolog++ the following table is given. This is not intended to be an exhaustive set of symbols found in this chapter but rather an initial set to bootstrap the reader into the examples.\n\n<table>\n<thead>\n<tr>\n<th>Method / Arity</th>\n<th>Method are referred to by the / symbol, with the name of the method on the left and its arity (number of arguments) on the right.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Function // Arity</td>\n<td>Functions are referred to by the // symbol, with the name of the function on the left and its arity (number of arguments) on the right.</td>\n</tr>\n<tr>\n<td>Attribute</td>\n<td>Attributes are referred to by their name alone.</td>\n</tr>\n<tr>\n<td>Instance <- Message</td>\n<td><- is the principal symbol of Prolog++, and indicates that the message on the right is to be sent to the instance on the left.</td>\n</tr>\n<tr>\n<td>Instance @ Attribute</td>\n<td>@ is the symbol used to indicate the value of an instance’s attribute.</td>\n</tr>\n</tbody>\n</table>\n\nThe case studies cover a range of problems, each of which illustrates different aspects of the language. They are as follows :-\n\n**Simulation**\nA simulation of the activities of a bank which investigates different queueing models.\n\n**Resource Scheduling**\nConstructing a school timetable with respect to both physical and desired constraints.\n\n**Database**\nA stock control system including a report generator for periodic trading results.\n\n**Fault Diagnosis**\nDiagnosing faults in an automobile according to exhibited symptoms and counter symptoms.\nChapter 5 - A Case Study In Simulation\n\nThis case study will investigate the application of Prolog++ to event-driven simulation, specifically within a banking environment. It will illustrate various aspects of Prolog++, including polymorphism, message broadcasting, the use of abstract data types and the structuring of a class hierarchy, albeit a small one. More specifically, it will call upon the use of class variables within the definitions of attributes, functions and methods.\n\nA very important characteristic of the overall object-oriented approach is the way in which code is re-utilised for seemingly different situations. Exactly the same routines will be employed for simulating single-queue and multiple-queue scenarios.\n\nThe Problem\nA bank needs information to rationalise its staffing requirements according to its expected business. An optimum solution, based upon simulating the bank’s processes, will minimize the number of bank tellers required together with their idle time, whilst simultaneously reducing how long customers have to wait before being served. Obviously, this is an impossible task as anybody who has tried to use a bank during lunch hours will testify.\n\nWithin the banking environment certain events can be recognised; the arrival of customers, their joining of a queue, being served by a teller, and finally leaving the bank. Arrivals and service time are of random durations, and will be modelled accordingly.\n\nThe biggest factor which affects customer turnaround time is the number of queues, ranging from a single communal queue for all of the bank tellers to individual queues for each. Hopefully, an object-oriented approach will be able to simulate both with very little specialisation of the code. From the viewpoint of a bank teller, s/he does not care whether the supply queue is private or shared with others. From the viewpoint of a customer, s/he will always choose the smallest queue, however many there are.\n\nIn order to make an informed judgement, various statistics will need to be collected. These will include such values as the total number of customers served, the average size of queues, the average time waiting in each queue, and many more.\n\nThe input parameters for each simulation will include such values as how long the bank is open for, how many tellers there are, the number of queues, and others.\n\nThe Classes\nFrom the discussion above, various entities in the problem domain can be identified. These are bank, teller, customer and customer queue. Of course, since it is a simulation problem it will also involve the entity time.\n\nIn addition, a customer queue can be thought of as a general queue, showing the same behaviour as queues but also incorporating some of the special features of customers.\nThe following sections define the various classes in the bank simulation, except \\textit{queue\\_with\\_statistics} which can be found in the appendix on library classes.\n\n\\textbf{The \"clock\" Class}\n\nThe \\texttt{clock} class represents the simulation time, and is defined by the following attributes and methods.\n\n\\begin{verbatim}\n% CLASS : clock\n% COMMENT: The clock used in the simulation of the bank\n\nclass clock .\n\n% DECLARATIONS\n\ncategory\n user ,\n bank . % A class in the bank simulation\n\npublic class attributes\n time_now is 0 , % The clock starts at time 0\n time_to_stop is 50 . % The clock ends at time 50\n\npublic methods\n stop / 1 , % Reset the stop time\n start / 0 , % Restart the clock\n tick / 0 , % A tick of the clock\n still_open / 0 , % The clock has not yet reached the stop time\n closed / 0 , % The clock has passed the stop time\n print / 0 . % Print details about the clock\n\\end{verbatim}\nDEFINITIONS\n\n% METHOD : stop/1\n% COMMENT: Reset the stop time\nstop( Time ) :-\n time_to_stop := Time.\n\n% METHOD : start/0\n% COMMENT: Restart the clock\nstart :-\n time_now := 0.\n\ntick :-\n time_now += 1,\n nl,\n write( 'Time: ' ),\n write( @time_now ),\n nl.\n\nstill_open :-\n time_now < time_to_stop.\n\nclosed :-\n time_now >= time_to_stop.\n% METHOD : print/0\n% COMMENT: Print details about the clock\n\nprint :-\n write( 'Closing time' ) ,\n write( @time_to_stop ) ,\n nl,\n write( 'Last customer served at' ) ,\n write( @time_now ) ,\n nl,\n nl.\n\nend clock.\n\nThe “bank” Class\n\nThe declarations include a statement of its only parent class (bank_maths), various categories to which the bank class belongs and, finally, the methods which are publicly available to all other classes (setup/1/4, simulation/0 and print/0).\n\nThe setup methods handle various ways of setting up the bank in preparation for the simulation. The mode and service times control the behaviour of the bank tellers, the arrival distribution determines the frequency with which customers arrive at the bank and the stop time determines when the bank closes.\nChapter 5 - A Case Study in Simulation\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% METHOD: setup/4\n% COMMENT: Setup the bank configuration\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\nsetup( Mode ) :-\n setup( Mode,\n [(4,1),(3,2),(3,1),(2,2),(2,1)],\n [0,0,0,1,1,1,1,1,2,2,3],\n 20\n ).\n\nsetup( Mode, ServiceTimes, ArrivalDistribution, Stop ) :-\n teller <- setup( Mode, ServiceTimes ),\n customer <- setup( ArrivalDistribution ),\n clock <- stop( Stop ).\n\nThe simulation method is used to simulate the bank’s operations according to how it was set up. In the first phase customers arrive and are served at periodic intervals while the bank is still open for business, whereas in the second phase only the remaining customers are served.\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% METHOD: simulation/0\n% COMMENT: The simulation consists of two phases\n% 1) A period when the bank is open\n% 2) The bank is closed, but customers are still being served\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\nsimulation :-\n ( clock,\n customer,\n all instance customer_queue,\n all instance teller\n ) <- start,\n while clock <- still_open do\n ( clock <- tick,\n ( customer, % Customers arrive when open\n all instance customer_queue, % Update queue statistics\n all instance teller % Customers served when open\n ) <- after_tick\n ),\n while still_busy do\n ( clock <- tick,\n 44 Prolog++ Reference\n( \nall instance customer_queue, % Update queue statistics \nall instance teller % Customers served when busy \n) <- after_tick \n).\n\nstill_busy :-\n instance teller <- busy.\n\nstill_busy :-\n instance customer_queue <- non_empty.\n\nOnce the simulation has been performed the print method is used to report all of the \nstatistics which have been gathered. This is primarily done by broadcasting the print \nmessage to all parts of the simulation model.\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% METHOD : print/0\n% COMMENT: Print the statistics resulting from the simulation\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\nprint :-\n nl,\n write( 'Bank Simulation Statistics' ),\n nl,\n write( '=================================' ),\n nl,\n nl,\n( clock, customer, teller, customer_queue ) <- print.\n\rend bank.\n\nThe \"bank_maths\" Class\n\nThe methods of this class are available to all the other classes of the bank simulation,\nexcept the clock class, through the inheritance mechanism of Prolog++.\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% Some of the mathematics involved\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\nclass bank_maths .\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% DECLARATIONS\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\ncategories\n user ,\n bank . % A class in the bank simulation\nChapter 5 - A Case Study in Simulation\n\npublic methods\n\nnearest_number // 1 , % Nearest whole number\nvariation // 2 , % Mean variation\nrandom_member // 1 . % Random member of a list\n\nprivate methods\n\nvariation_sequence // 1 , % Auxiliary function\nmember // 2 . % Auxiliary function\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% METHOD : nearest_number//1\n% COMMENT: Nearest whole number\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\nnearest_number( Float ) is\n int( ( Float + 0.5) * 10 ) // 10.\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% METHOD : variation//2\n% COMMENT: Normal variation from the mean\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\nvariation( Mean, Variation ) is\n Mean + random_member( variation_sequence(Variation) ).\n\nvariation_sequence( 0 ) = [0].\nvariation_sequence( 1 ) = [-1,0,0,0,1].\nvariation_sequence( 2 ) = [-2,-1,-1,0,0,0,0,0,1,1,1,2].\nvariation_sequence( 3 ) = [-3,-2,-2,-1,-1,-1,-1,-1,0,0,0,0,0,0,0,1,1,1,2,2,3].\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% METHOD : random_member//1\n% COMMENT: Random member of a sequence\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\nrandom_member( Sequence ) is\n member( int(irand(length(Sequence))), Sequence ).\n\nmember( 0, [Item|_] ) = Item :-\n !.\n\nmember( Jth, [_|Sequence] ) is member( Jth-1, Sequence ).\n\nend bank_maths.\n\n46 Prolog++ Reference\nThe “teller” Class\n\nThis class simulates the behaviour of bank tellers. In particular, it introduces the concept of a class attribute, *queueing*, which governs the queueing model used when creating individual tellers.\n\n```prolog\nclass teller .\n\ncategories\n user , bank . % A class in the bank simulation\n\ninherit\n bank . % Inherit the bank methods\n\npublic class attributes\n queueing = personal . % Which queueing model to use?\n\npublic instance attributes\n teller_number . % Unique teller #\n\nprivate instance attributes\n mean_service_time , % A measure of a teller’s efficiency\n service_time_variation , % Variation in efficiency\n served_by_queue , % Which queue is the teller served by\n serving_customer , % Which customer they are serving\n aggregate_when_busy is 0 , % Aggregate time when teller is busy\n aggregate_customers is 0 , % Aggregate total of customers served\n time_until_next_free is 0 . % Time until teller next becomes free\n\npublic methods\n start / 0 , % Reset dynamics\n setup / 2 , % Setup teller characteristics\n when_created / 0 , % React to creation of a new teller\n after_tick / 0 , % What happens after a tick\n busy / 0 , % Is the teller busy?\n idle / 0 , % Is the teller idle?\n about_to_finish / 0 , % Is the teller about to finish?\n print / 0 . % Print statistics about the tellers\n```\nprivate methods\n start_serving_customer / 0, % Start serving the next customer\n finish_serving_customer/ 0, % Finish serving a customer\n print_me / 0, % Print statistics about a teller\n percentage_when_busy // 0. % Percentage time when teller is busy\n\nThe start method re-initialises all of the statistics which are gathered about tellers.\n\n% METHOD : start/0\n% COMMENT: Reset dynamic attributes\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\nstart :-\n reset( serving_customer ),\n reset( aggregate_when_busy ),\n reset( aggregate_customers ),\n reset( time_until_next_free ).\n\nThe setup method creates a number of tellers, each with their own average service time. Each teller is either linked to a communal queue or to their own personal queue.\n\n% METHOD : setup/2\n% COMMENT: Setup characteristics of the tellers & then create them\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\nsetup( Mode, ServiceTimes ) :-\n customer_queue <- delete_all,\n teller <- delete_all,\n queueing := Mode,\n ( Mode = communal -> create_communal( ServiceTimes )\n ; Mode = personal -> create_personal( ServiceTimes ) ) .\n\ncreate_communal( ServiceTimes ) :-\n customer_queue <- create( Queue, [queue_number = 1] ),\n create_communal( ServiceTimes, 1, Queue ).\n\ncreate_communal( [], _, _ ).\n\ncreate_communal( ([MeanServiceTime, ServiceVariation]|ServiceTimes],\n Number,\n Queue\n) :-\n super <- create(\n Queue,\n served_by_queue = Queue,\nmean_service_time = MeanServiceTime, \nservice_time_variation = ServiceVariation, \nteller_number = Number \n],\ncreate_communal( ServiceTimes, +Number+1, Queue ).\n\ncreate_personal( ServiceTimes ) :-\n create_personal( ServiceTimes, 1 ).\n\ncreate_personal( [], _ ).\n\ncreate_personal( \n [(MeanServiceTime,ServiceVariation)|ServiceTimes], Number \n) :-\n customer_queue <- create( Queue, [queue_number = Number] ),\n super <- create( \n _, \n [ \n served_by_queue = Queue, \n mean_service_time = MeanServiceTime, \n service_time_variation = ServiceVariation, \n teller_number = Number \n ] \n ),\n create_personal( ServiceTimes, +Number+1 ).\n\nThe following is an example of data-driven programming. The when_created method is not actually called by the program itself but reacts whenever a new teller is created.\n\nwhen_created :-\n write( 'Teller #' ),\n write( @teller_number ),\n write( ' draws customers from queue #' ),\n write( @served_by_queue@queue_number ),\n nl.\nAt each tick of the clock the tellers need to assess what they are doing, whether or not they have finished serving their current customer and whether they can start serving the next customer.\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% METHOD : after_tick/0\n% COMMENT: What do tellers do after each tick of the clock\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\n% Start serving the next customer in the teller’s queue\n\nafter_tick :-\n idle,\n start_serving_customer,\n !,\n time_until_next_free := @serving_customer@work_load\n + variation(\n mean_service_time,\n service_time_variation\n ),\n aggregate_when_busy += 1,\n aggregate_customers += 1.\n\n% Finish serving a customer at this tick of the clock\n\nafter_tick :-\n about_to_finish,\n !,\n aggregate_when_busy += 1,\n time_until_next_free := 0,\n finish_serving_customer.\n\n% Still serving a customer\n\nafter_tick :-\n busy,\n !,\n aggregate_when_busy += 1,\n time_until_next_free -= 1.\n\n% Idle time when there are no customers in the teller’s queue\n\nafter_tick.\nThe notion of a busy teller revolves around the time when s/he next becomes free, which is a function of both their own efficiency and the work-load of the customer.\n\nbusy :-\n @time_until_next_free > 0.\n\nidle :-\n @time_until_next_free = 0.\n\nabout_to_finish :-\n @time_until_next_free = 1.\n\nThese methods handle the serving of a customer.\n\nstart_serving_customer :-\n serving_customer := @served_by_queue@next_customer,\n write( 'Teller #' ),\n write( @teller_number ),\n write( ' starts serving customer #' ),\n write( @serving_customer@customer_number ),\n nl.\n\nfinish_serving_customer :-\n write( 'Teller #' ),\n write( @teller_number ),\n write( ' finish serving customer #' ),\n write( @serving_customer@customer_number ),\n nl,\n @served_by_queue <- exit_customer,\n @serving_customer <- delete,\n reset( serving_customer ).\n\nAt the end of the simulation the print message is broadcast to all parts of the model. Here the statistics of each teller are printed.\n% METHOD : print/0\n% COMMENT: Print statistics about the tellers\nprint :-\n write( 'Number of bank tellers : ' ),\n write( @length( all instance teller ) ),\n nl,\n write( 'Mode of operation : ' ),\n write( @queueing ),\n write( ' queue(s)' ),\n nl,\n nl,\n all instance teller <- print_me.\n\n% METHOD : print_me/0\n% COMMENT: Print statistics about a particular teller\nprint_me :-\n write( 'Teller # ' ),\n write( @teller_number ),\n nl,\n write( 'Total number of customers served : ' ),\n write( @aggregate_customers ),\n nl,\n write( 'Percentage time spent serving customers : ' ),\n write( @percentage_when_busy ), write( '%' ),\n nl,\n write( 'Mean time to serve a customer : ' ),\n write( @mean_service_time ),\n nl,\n write( 'Variation in service time : ' ),\n write( @service_time_variation ),\n nl,\n nl.\n\n% METHOD : percentage_when_busy/0\n% COMMENT: Percentage time when teller is busy serving customers\npercentage_when_busy is nearest_number(\n aggregate_when_busy /\n clock@time_now\n)\nThe \"customer\" Class\n\nThe primary purpose of this class is to model the arrival distribution of the bank’s customers.\n\n@verbatim\n% Typical customers arriving at the bank have\n% different service requirements and so different\n% work-loads\n\nclass customer.\n\n@verbatim\n% DECLARATIONS\n\ncategory user, bank. % A class in the bank simulation\n\ninherit bank. % Inherit the bank methods\n\npublic class attributes\n arrival_distribution, % Distribution of customer arrivals\n mean_work_load is 2, % Mean work-load of each customer\n work_load_variation is 1, % Variation in the work-loads\n aggregate_customers is 0, % The number of customers so far\n aggregate_work_load is 0. % Aggregate work-load of all customers\n\npublic instance attributes\n customer_number, % Unique customer #\n work_load. % The work-load of a specific customer\n\npublic methods\n setup / 1, % Setup characteristics of the customers\n start / 0, % Delete any old customers\n after_tick / 0, % What happens after a tick of the clock\n print / 0. % Print statistics about the customers\n\nprivate methods\n create / 1, % Create N new customers\n when_created / 0. % Calculate work-load for next customer\n@endverbatim\n% METHOD : setup/1\n% COMMENT: Setup characteristics of the customers\n% arriving\nsetup( ArrivalDistribution ) :-\n arrival_distribution := ArrivalDistribution.\n\nThe *start* method re-initialises all of the statistics which are gathered about customers.\n\n% METHOD : start/0\n% COMMENT: Delete any old customers !!!\n\nstart :-\n delete_all,\n aggregate_customers := 0,\n aggregate_work_load := 0.\n\nAt each tick of the clock a number of customers will arrive. This is determined by the arrival distribution when the simulation is set up.\n\n% METHOD : after_tick/0\n% COMMENT: After each tick calculate how many customers will arrive and send them to the shortest queues (at the time of their creation)\n\nafter_tick :-\n create( @random_member( @arrival_distribution ) ).\n\n% METHOD : create/1\n% COMMENT: Create N customers with his/her work load & increment counter\n\ncreate( 0 ) :-\n !.\ncreate( N ) :-\n super <- create( Customer ),\n customer_queue@smallest <- new_customer( Customer ),\n create( +N-1 ).\n% METHOD : when_created/0\n% COMMENT: Calculate the work-load of a customer who has just arrived, and set his/her customer #\nwhen_created :-\n aggregate_customers += 1,\n customer_number := aggregate_customers,\n work_load := variation( mean_work_load, work_load_variation ),\n aggregate_work_load += work_load, write( 'Next customer #' ), write( @customer_number ), write( ' with work-load ' ), write( @work_load ), write( ' joins queue #' ), write( (customer_queue@smallest)@queue_number ), write( ' (length = ' ), write( (customer_queue@smallest)@real_size ), write( ')' ), nl.\n\nAt the end of the simulation the print message is broadcast to all parts of the model. Here the statistics of each customer are printed.\n\n% METHOD : print/0\n% COMMENT: Print statistics about the customers\nprint :-\n write( 'Distribution of customer arrivals : ' ),\n write( @arrival_distribution ), nl,\n write( 'Mean work-load for customers arriving : ' ),\n write( @mean_work_load ), nl,\n write( 'Variation in the work-load of customers : ' ),\n write( @work_load_variation ), nl,\n write( 'Total number of customers which arrived : ' ),\n write( @aggregate_customers ), nl,\n write( 'Total work-load of all customers : ' ),\n write( @aggregate_work_load ), nl, nl.\nend customer.\n\nThe \"customer_queue\" Class\n\nThe customer_queue class is a specialisation of a general library class for queues which has been adapted for bank customers. A special attribute of this class identifies which is the smallest queue.\n\n% A queue of customers with statistics\n% about average size and wait time\n\nclass customer_queue .\n\ncategory bank , % A class in the bank simulation\n user .\n\ninherits customer , % Inherit the customer & bank methods\n queue_with_statistics . % Also inherit from statistical queues\n\npublic class attributes\n smallest = @smallest_now . % The smallest queue\n\npublic instance attributes\n queue_number , % Number of the queue\n real_size is 0 . % Real queue size includes busy tellers\n\nprivate instance attributes\n cumulative_size is 0 . % The cumulative size over time\n\npublic methods\n start / 0 , % Reset dynamic attributes\n when_created / 0 , % Definitely changes the smallest queue\n new_customer / 1 , % May change the smallest queue\n next_customer / 1 , % Pop customer before starting service\n exit_customer / 0 , % Reduce size at end of service\n after_tick / 0 , % What to do after a tick\n smallest_now // 0 , % Re-compute the smallest queue now\n print _ / 0 . % Print statistics about the customer queues\n\nprivate methods\n smallest_now // 1 , % Auxilliary function\nsmallest_now // 2 , % Auxilliary function\nsmaller // 2 , % Auxilliary function\nprint_me / 0 , % Print statistics about a particular queue\naverage_size // 0 , % Average size over time\naverage_wait // 0 . % Average waiting time in the queue\n\nThe start method re-initialises all of the statistics which are gathered about customer queues.\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %METHOD : start/0 %COMMENT: Reset dynamic attributes %%%%%%%%%%%%%%%%%%%%%%%%%%%%%\nstart :-\n Number is queue_number,\n reset,\n queue_number := Number.\n\nWhenever a new queue is created it automatically becomes the smallest queue. Whenever a customer joins the smallest queue then it may no longer be the smallest. The smallest is calculated by comparing the \"real\" sizes of each of the queues.\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %METHOD : when_created/0 %COMMENT: Self becomes the smallest queue %%%%%%%%%%%%%%%%%%%%%%%%%%%%%\nwhen_created :-\n smallest := self.\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %METHOD : new_customer/1 %COMMENT: Push a customer onto the back of this %queue. %Be careful if it was the smallest queue! %%%%%%%%%%%%%%%%%%%%%%%%%%%%%\nnew_customer( Item ) :-\n super <- push( Item ),\n real_size += 1,\n ( smallest = self -> reset( smallest ) ; true ).\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %METHOD : smallest_now//0 %METHOD : smallest_now//1 %METHOD : smallest_now//2 %COMMENT: Compute and return the smallest customer %queue %Prolog++ Reference\nsmallest_now = @smallest_now( all instance class self ).\n\nsmallest_now( [Queue|Queues] ) = @smallest_now( Queues, Queue ).\n\nsmallest_now( [], Smallest ) = Smallest.\n\nsmallest_now( [Queue|Queues], SmallestSoFar ) =\n @smallest_now( Queues, @smaller(Queue,SmallestSoFar) ).\n\nsmaller( Queue1, Queue2 ) = Queue1 :-\n Queue1 @ real_size < Queue2 @ real_size,\n !.\n\nsmaller( _, Queue2 ) = Queue2.\n\nWhenever a teller becomes free the next customer is removed from her/his queue. However, that customer is still considered as if they were still in the queue until after they have been served as this influences which queue new arrivals will join. When the customer eventually exits the bank their queue might then become the smallest.\n\n% METHOD: next_customer/1\n% COMMENT: Pop a customer from the front of queue\n\nnext_customer( Item ) :-\n super <- pop( Item ).\n\n% METHOD: exit_customer/0\n% COMMENT: Now we can reduce the \"real size\" of the\n% queue !\n% Does it become the smallest queue ?\n\nexit_customer :-\n real_size -= 1,\n smallest := smaller( self, smallest ).\n\nAt each tick of the clock the “real” size of the queue is added to its cumulative size over time.\n\n% METHOD: after_tick/0\n% COMMENT: What happens to queues after a tick of\n% the clock\n\n58 Prolog++ Reference\nafter_tick :-\n cumulative_size += real_size.\n\nAt the end of the simulation the print message is broadcast to all parts of the model. Here the statistics of each queue are printed.\n\n%ethod: print/0\n% COMEN: Print statistics about the customer queues\n\nprint :-\n write( 'Number of customer queues : ' ),\n write( @length( all instance customer_queue ) ),\n nl,\n nl,\n all instance customer_queue <- print_me.\n\n%ethod: print_me/0\n% STYE : PRIVATE PROCEDURE\n% COMEN: Print statistics about a particular queue\n\nprint_me :-\n write( 'Queue # ' ),\n write( @queue_number ),\n nl,\n write( 'Total number of customers in queue : ' ),\n write( @aggregate_size ),\n nl,\n write( 'Maximum number of customers in queue : ' ),\n write( @peak_size ),\n nl,\n write( 'Average number of customers in queue : ' ),\n write( @average_size ),\n nl,\n write( 'Average time for each customer in queue : ' ),\n write( @average_wait ),\n nl.\n\n%ethod: average_size//0\n% COMEN: The average size of the queue over time\n\naverage_size is nearest_number( cumulative_size / clock@time_now ).\n% METHOD: average_wait // 0\n% COMMENT: The average waiting time each customer\n% spends in the queue\n\naverage_wait is 0 :-\n @aggregate_size = 0,\n !.\n\naverage_wait is nearest_number( cumulative_size / aggregate_size ).\n\nend customer_queue.\n\nThe Output\n\nThe following listings were cut from two typical runs of the simulation. In the first run a\nsingle communal queue was used and in the second run individual queues were used for\neach of 5 bank tellers.\n\nSingle, Communal Queue\n\nThe bank is set up with a communal model where all of the tellers draw customers from a\nsingle queue.\n\n?- bank <- setup( communal ) .\n\nTeller #1 draws customers from queue #1\nTeller #2 draws customers from queue #1\nTeller #3 draws customers from queue #1\nTeller #4 draws customers from queue #1\nTeller #5 draws customers from queue #1\n\nA simulation run with the output at each tick of the clock.\n\n?- bank <- simulation .\n\nTime: 1\nNext customer #1 with work-load 2 joins queue #1 (length = 0)\nTeller #1 starts serving customer #1\n\nTime: 2\nNext customer #2 with work-load 2 joins queue #1 (length = 1)\nTeller #2 starts serving customer #2\n\nTime: 3\nNext customer #3 with work-load 3 joins queue #1 (length = 2)\nTeller #3 starts serving customer #3\n\nTime: 4\n\nNext customer #4 with work-load 1 joins queue #1 (length = 3)\nTeller #4 starts serving customer #4\n\nTime: 5\n\nTime: 6\nNext customer #5 with work-load 1 joins queue #1 (length = 4)\nNext customer #6 with work-load 2 joins queue #1 (length = 5)\nNext customer #7 with work-load 1 joins queue #1 (length = 6)\nTeller #1 finish serving customer #1\nTeller #2 finish serving customer #2\nTeller #5 starts serving customer #5\n\nTime: 7\nNext customer #8 with work-load 2 joins queue #1 (length = 5)\nTeller #1 starts serving customer #6\nTeller #2 starts serving customer #7\n\nTime: 8\nNext customer #9 with work-load 2 joins queue #1 (length = 6)\nTeller #3 finish serving customer #3\nTeller #4 finish serving customer #4\n\nTime: 9\nNext customer #10 with work-load 2 joins queue #1 (length = 5)\nTeller #3 starts serving customer #8\nTeller #4 starts serving customer #9\n\nTime: 10\nNext customer #11 with work-load 2 joins queue #1 (length = 6)\nTeller #1 finish serving customer #6\nTeller #5 finish serving customer #5\n\nTime: 11\nNext customer #12 with work-load 3 joins queue #1 (length = 5)\nTeller #1 starts serving customer #10\nTeller #5 finish serving customer #5\n\nTime: 12\nNext customer #13 with work-load 2 joins queue #1 (length = 6)\nTeller #2 finish serving customer #7\n\nTime: 13\nNext customer #14 with work-load 2 joins queue #1 (length = 6)\nTeller #2 starts serving customer #12\nTeller #3 finish serving customer #8\nTeller #4 finish serving customer #9\n\nTime: 14\nNext customer #15 with work-load 2 joins queue #1 (length = 5)\nNext customer #16 with work-load 2 joins queue #1 (length = 6)\nTeller #3 starts serving customer #13\nTeller #4 starts serving customer #14\n\nTime: 15\nNext customer #17 with work-load 1 joins queue #1 (length = 7)\nNext customer #18 with work-load 3 joins queue #1 (length = 8)\nTeller #1 finish serving customer #10\n\nTime: 16\nTeller #1 starts serving customer #15\n\nTime: 17\nNext customer #19 with work-load 1 joins queue #1 (length = 8)\nTeller #3 finish serving customer #13\n\nTime: 18\nTeller #3 starts serving customer #16\nTeller #5 finish serving customer #11\n\nTime: 19\nNext customer #20 with work-load 2 joins queue #1 (length = 7)\nTeller #2 finish serving customer #12\nTeller #5 starts serving customer #17\n\nTime: 20\nNext customer #21 with work-load 3 joins queue #1 (length = 7)\nTeller #1 finish serving customer #15\nTeller #2 starts serving customer #18\nTeller #4 finish serving customer #14\n\nTime: 21\nTeller #1 starts serving customer #19\nTeller #3 finish serving customer #16\nTeller #4 starts serving customer #20\n\nTime: 22\nTeller #3 starts serving customer #21\n\nTime: 23\nTeller #5 finish serving customer #17\n\nTime: 24\nTeller #1 finish serving customer #19\n\nTime: 25\nTime: 26\n\nTime: 27\nTeller #2 finish serving customer #18\nTeller #3 finish serving customer #21\nTeller #4 finish serving customer #20\n\nA print of the statistics which have been gathered.\n\n?- bank <- print .\n\nBank Simulation Statistics\n==========================\nClosing time : 20\nLast customer served at : 27\n\nDistribution of customer arrivals : [0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 3]\nMean work-load for customers arriving : 2\nVariation in the work-load of customers : 1\nTotal number of customers which arrived : 21\nTotal work-load of all customers : 41\n\nNumber of bank tellers : 5\nMode of operation : communal queue(s)\n\nTeller # 1\nTotal number of customers served : 5\nPercentage time spent serving customers : 89%\nMean time to serve a customer : 2\nVariation in service time : 2\n\nTeller # 2\nTotal number of customers served : 4\nPercentage time spent serving customers : 96%\nMean time to serve a customer : 3\nVariation in service time : 2\n\nTeller # 3\nTotal number of customers served : 5\nPercentage time spent serving customers : 93%\nMean time to serve a customer : 2\nVariation in service time : 1\n\nTeller # 4\nTotal number of customers served : 4\nPercentage time spent serving customers : 89%\nMean time to serve a customer : 3\nVariation in service time : 1\nTeller # 5\nTotal number of customers served : 3\nPercentage time spent serving customers : 67%\nMean time to serve a customer : 3\nVariation in service time : 2\n\nNumber of customer queues : 1\n\nQueue #1\nTotal number of customers in queue : 21\nMaximum number of customers in queue : 4\nAverage number of customers in queue : 6\nAverage time for each customer in queue : 7\n\nMultiple, Personal Queues\nThe bank is set up with a personal model where each of the tellers will draw customers from their own individual queue.\n\n?- bank <- setup( personal ) .\n\nTeller #1 draws customers from queue #1\nTeller #2 draws customers from queue #2\nTeller #3 draws customers from queue #3\nTeller #4 draws customers from queue #4\nTeller #5 draws customers from queue #5\n\nA simulation run with the output at each tick of the clock.\n\n?- bank <- simulation .\n\nTime: 1\nNext customer #1 with work-load 2 joins queue #2 (length = 0)\nNext customer #2 with work-load 2 joins queue #1 (length = 0)\nTeller #1 starts serving customer #2\nTeller #2 starts serving customer #1\n\nTime: 2\nNext customer #3 with work-load 1 joins queue #3 (length = 0)\nTeller #3 starts serving customer #3\n\nTime: 3\nNext customer #4 with work-load 2 joins queue #4 (length = 0)\nTeller #4 starts serving customer #4\n\nTime: 4\nNext customer #5 with work-load 2 joins queue #5 (length = 0)\nTeller #1 finish serving customer #2\n\n64 Prolog++ Reference\nTeller #5 starts serving customer #5\n\nTime: 5 \nNext customer #6 with work-load 2 joins queue #1 (length = 0) \nTeller #1 starts serving customer #6 \nTeller #2 finish serving customer #1\n\nTime: 6 \nNext customer #7 with work-load 2 joins queue #2 (length = 0) \nNext customer #8 with work-load 2 joins queue #1 (length = 1) \nTeller #2 starts serving customer #7 \nTeller #3 finish serving customer #3\n\nTime: 7\n\nTime: 8 \nNext customer #9 with work-load 2 joins queue #3 (length = 0) \nTeller #3 starts serving customer #9 \nTeller #4 finish serving customer #4 \nTeller #5 finish serving customer #5\n\nTime: 9 \nNext customer #10 with work-load 2 joins queue #4 (length = 0) \nTeller #1 finish serving customer #6 \nTeller #4 start serving customer #10\n\nTime: 10 \nNext customer #11 with work-load 2 joins queue #5 (length = 0) \nTeller #1 start serving customer #8 \nTeller #5 start serving customer #11\n\nTime: 11 \nNext customer #12 with work-load 3 joins queue #1 (length = 1) \nTeller #3 finish serving customer #9\n\nTime: 12 \nNext customer #13 with work-load 2 joins queue #3 (length = 0) \nNext customer #14 with work-load 3 joins queue #2 (length = 1) \nTeller #2 finish serving customer #7 \nTeller #3 start serving customer #13\n\nTime: 13 \nNext customer #15 with work-load 2 joins queue #2 (length = 1) \nTeller #2 start serving customer #14\n\nTime: 14 \nNext customer #16 with work-load 2 joins queue #3 (length = 1) \nNext customer #17 with work-load 2 joins queue #4 (length = 1) \nTeller #1 finish serving customer #8\n\nProlog++ Reference\nTeller #4 finish serving customer #10\n\nTime: 15\nTeller #1 starts serving customer #12\nTeller #4 starts serving customer #17\nTeller #5 finish serving customer #11\n\nTime: 16\nNext customer #18 with work-load 3 joins queue #5 (length = 0)\nTeller #3 finish serving customer #13\nTeller #5 starts serving customer #18\n\nTime: 17\nNext customer #19 with work-load 3 joins queue #1 (length = 1)\nTeller #3 starts serving customer #16\n\nTime: 18\nNext customer #20 with work-load 2 joins queue #3 (length = 1)\n\nTime: 19\nTeller #2 finish serving customer #14\nTeller #4 finish serving customer #17\n\nTime: 20\nNext customer #21 with work-load 2 joins queue #4 (length = 0)\nTeller #2 starts serving customer #15\nTeller #3 finish serving customer #16\nTeller #4 starts serving customer #21\n\nTime: 21\nTeller #1 finish serving customer #12\nTeller #3 starts serving customer #20\n\nTime: 22\nTeller #1 starts serving customer #19\nTeller #5 finish serving customer #18\n\nTime: 23\n\nTime: 24\nTeller #3 finish serving customer #20\n\nTime: 25\nTeller #4 finish serving customer #21\n\nTime: 26\nTeller #2 finish serving customer #15\nTime: 27\n\nTime: 28\nTeller #1 finish serving customer #19\n\nA print of the statistics which have been gathered.\n\n?- bank <- print .\n\nBank Simulation Statistics\n=================================\n\nClosing time : 20\nLast customer served at : 28\n\nDistribution of customer arrivals : [0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 2, 2, 3]\nMean work-load for customers arriving : 2\nVariation in the work-load of customers : 1\nTotal number of customers which arrived : 21\nTotal work-load of all customers : 45\n\nNumber of bank tellers : 5\nMode of operation : personal queue(s)\n\nTeller # 1\nTotal number of customers served : 5\nPercentage time spent serving customers : 100%\nMean time to serve a customer : 2\nVariation in service time : 2\n\nTeller # 2\nTotal number of customers served : 4\nPercentage time spent serving customers : 93%\nMean time to serve a customer : 3\nVariation in service time : 2\n\nTeller # 3\nTotal number of customers served : 5\nPercentage time spent serving customers : 79%\nMean time to serve a customer : 2\nVariation in service time : 1\n\nTeller # 4\nTotal number of customers served : 4\nPercentage time spent serving customers : 82%\nMean time to serve a customer : 3\nVariation in service time : 1\n\nTeller # 5\nTotal number of customers served : 3\nPercentage time spent serving customers : 64%\nMean time to serve a customer : 3\nVariation in service time : 2\n\nNumber of customer queues : 5\n\nQueue #1\nTotal number of customers in queue : 5\nMaximum number of customers in queue : 1\nAverage number of customers in queue : 1\nAverage time for each customer in queue : 8\n\nQueue #2\nTotal number of customers in queue : 4\nMaximum number of customers in queue : 2\nAverage number of customers in queue : 1\nAverage time for each customer in queue : 9\n\nQueue #3\nTotal number of customers in queue : 5\nMaximum number of customers in queue : 1\nAverage number of customers in queue : 1\nAverage time for each customer in queue : 6\n\nQueue #4\nTotal number of customers in queue : 4\nMaximum number of customers in queue : 1\nAverage number of customers in queue : 1\nAverage time for each customer in queue : 6\n\nQueue #5\nTotal number of customers in queue : 3\nMaximum number of customers in queue : 1\nAverage number of customers in queue : 1\nAverage time for each customer in queue : 6\nChapter 6 - A Case Study In Resource Management\n\nThis case study will apply Prolog++ to the area of resource management. The resources will be represented as instance hierarchies, utilising default values and inheritance to classify them. A high degree of polymorphism is incorporated with variations of the same method being defined in related classes.\n\nAn important feature of Prolog++ exhibited by this study is the ability to store database records locally, rather than having a global repository. This can be extended by having several local databases distributed throughout the instance hierarchy.\n\nThe example will also illustrate the use of daemons to monitor the progress made by the scheduling algorithm. This use of daemons can be thought of as a debugging tool that is tailored to the specific requirements of the problem.\n\nThe Problem\nEvery school has the perennial task of scheduling its most important resource, its teachers. The problem varies from year to year, with different classes, the arrival and departure of teachers and perhaps even fundamental changes which put different constraints on the timetable.\n\nEach teacher and each class has its own requirements which must be fulfilled by the timetable. Classes should be taught a broad range of subjects; a timetable that continually scheduled mathematics might be desired by some members of the class, but certainly not by the majority. Teachers usually have expertise in a small range of subjects, and desire certain free periods when they can pursue other activities.\n\nIn this prototype two specific constraints will be applied to the timetable. The first constraint is that teachers cannot physically be in two places at the same time, however hard they try. The second constraint is that each class must be taught a different subject for each period of a particular day.\n\nThe information about each teacher’s subjects and desired free time will be represented as an instance hierarchy, where default information is put at the most general level.\n\nThe Classes\nThe main entities in this problem are the generic teacher, form, subject and period. These are then specialized with particular teachers, particular forms, particular subjects and particular periods. The set of periods is considered to represent a single day in the school timetable.\n\nThe scheduling algorithm will be implemented in a separate class called timetable, which gathers information by sending messages to and asking values of the other objects. The result is stored as a local database of 4-tuples, where each tuple consists of the form, period, teacher and subject.\nThe \"timetable\" Class\n\n% Set up & create a timetable satisfying all of the % constraints\n\nclass timetable .\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% DECLARATIONS %\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\ncategory\n school , % A class in the school timetable\n user . % Also, a user class\n\ninherit\ndb . % Inherit the database stuff!\n\npublic methods\n setup / 0 , % Set up the teachers, subjects,\n % forms & periods for this school\n make / 0 , % Make the timetable according to\n % the school setup\n make / 1 , % Make with max. depth of swaps\n print / 0 . % Print from different perspectives\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% DEFINITIONS %\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\n% METHOD : setup/0\n% COMMENT: Print from different perspectives\n\nprint :-\n [form,period,teacher,subject] <- print.\n\n% METHOD : setup/0\n% COMMENT: Set up the teachers, subjects, forms &\n% periods for this school\n\nsetup :-\n [form,period,teacher,subject] <- delete_all,\nform\n<- ( \ncreate( _, [], first_year ),\ncreate( _, [], second_year ),\ncreate( _, [], third_year ),\ncreate( _, [], fourth_year )\n),\nperiod\n<- ( \ncreate( _, [], 1 ),\ncreate( _, [], 2 ),\ncreate( _, [], 3 ),\ncreate( _, [], 4 ),\ncreate( _, [], 5 )\n),\nteacher\n<- ( \ncreate( _, [ subjects=[french,biology], \n freetime=[1,4] ], nicky ),\ncreate( _, [ subjects=[maths,music], \n freetime=[] ], brian ),\ncreate( _, [ subjects=[maths], \n freetime=[] ], dave ),\ncreate( _, [ subjects=[french,prolog], \n freetime=[2,3,5] ], clive ),\ncreate( _, [ subjects=[accountancy], \n freetime=[2,4] ], diane ),\ncreate( _, [ subjects=[maths,'prolog++'], \n freetime=[3] ], phil )\n),\nsubject\n<- ( \ncreate( _, [], maths ),\ncreate( _, [], music ),\ncreate( _, [], french ),\ncreate( _, [], prolog ),\ncreate( _, [], biology ),\ncreate( _, [], 'prolog++' ),\ncreate( _, [], accountancy )\n).\nwhen_created :- \nwrite( 'Create ' ),\nwrite( class ),\nwrite( ':' ),\nwrite( mnemonic ),\nnl.\n% METHOD: make/0/1\n% COMMENT: Make the timetable according to how the school was setup\n\nmake :-\n make( 3 ).\n\nmake( Effort ) :-\n length( E, Effort ),\n dynamic( entry / 4 ),\n forall\n ( Form = instance form,\n Period = instance period\n )\n do\n fill_entry( E, Form, Period, Teacher, Subject ).\n\n% An (un)filled timetable entry\n\nunfilled_entry( Form, Period ) :-\n % select a form\n Form = instance form,\n % select a period\n Period = instance period,\n % which has not yet been assigned\n \\+ filled_entry( Form, Period, _, _ ).\n\nfilled_entry( Form, Period, Teacher, Subject ) :-\n call( entry( Form, Period, Teacher, Subject ) ).\n\n% Fill an entry by finding one & asserting it\n\nfill_entry( E, Form, Period, Teacher, Subject ) :-\n find_entry( E, Form, Period, Teacher, Subject ),\n assert( Form, Period, Teacher, Subject ).\n\nfill_entry( _, _, _, _, _ ).\nChapter 6 - A Case Study In Resource Management\n\n% A good entry in the timetable\n\nfind_entry( _, Form, Period, Teacher, Subject ) :-\n% select a teacher\n Teacher = instance teacher,\n% who can teach during this period\n Teacher <- teach_period( mnemonic Period ),\n% and who is not already elsewhere\n \\+ filled_entry( _, Period, Teacher, _ ),\n% select a subject\n Subject = instance subject,\n% which the teacher can teach\n Teacher <- teach_subject( mnemonic Subject ),\n% and which is not already taught to the form\n \\+ filled_entry( Form, _, _, Subject ).\n\n% Swap a teacher from another form to this form\n\nfind_entry( [__E], FormA, Period, TeacherA, SubjectA ) :-\n% select a teacher\n TeacherA = instance teacher,\n% who can teach during this period\n TeacherA <- teach_period( mnemonic Period ),\n% but is already teaching some other form\n filled_entry( FormB, Period, TeacherA, _ ),\n% select a subject\n SubjectA = instance subject,\n% which the teacher can teach\n TeacherA <- teach_subject( mnemonic SubjectA ),\n% and which is not already taught to the form\n \\+ filled_entry( FormA, _, _, SubjectA ),\n% re-fill the entry for that other form\n find_entry( E, FormB, Period, TeacherB, SubjectB ),\n% with a different teacher\n TeacherB \\= TeacherA,\n% un-assign our teacher from that other form\n% and re-assign the different teacher\n write( 'Swap teacher ...' ), nl,\n retract( FormB, Period, TeacherA, _ ),\n assert( FormB, Period, TeacherB, SubjectB ).\n% Swap a subject from another period to this period\n\nfind_entry( [\\_|E], Form, PeriodA, TeacherA, SubjectA ) :-\n % select a teacher\n TeacherA = instance teacher,\n % who can teach during this period\n TeacherA <- teach_period( mnemonic PeriodA ),\n % and who is not already elsewhere\n \\+ filled_entry( _, PeriodA, TeacherA, _ ),\n % select a subject\n SubjectA = instance subject,\n % which the teacher can teach\n TeacherA <- teach_subject( mnemonic SubjectA ),\n % and which is already taught to the form\n filled_entry( Form, PeriodB, _, SubjectA ),\n % re-fill the entry for that other period?\n find_entry( E, Form, PeriodB, TeacherB, SubjectB ),\n % with a different subject\n SubjectA \\= SubjectB,\n % un-assign the subject from that other period\n % and re-assign the different subject\n write( 'Swap subject ...' ), nl,\n retract( Form, PeriodB, _, SubjectA ),\n assert( Form, PeriodB, TeacherB, SubjectB ).\n\n% Local database management with echoing\n\nassert( Form, Period, Teacher, Subject ) :-\n super <- assert( entry(Form,Period,Teacher,Subject) ),\n write( '+ ' ),\n write( mnemonic Form ), write( '-' ),\n write( mnemonic Period ), write( '-' ),\n write( mnemonic Teacher ), write( '-' ),\n write( mnemonic Subject ), nl.\n\nretract( Form, Period, Teacher, Subject ) :-\n super <- retract( entry(Form,Period,Teacher,Subject) ),\n write( '-' ),\n write( mnemonic Form ), write( '-' ),\n write( mnemonic Period ), write( '-' ),\n write( mnemonic Teacher ), write( '-' ),\n write( mnemonic Subject ), nl.\n\nend timetable.\n\nThe form Class\n\n74 Prolog++ Reference\n% General attributes & methods for all forms\n\nclass form .\n\ncategory school , % A class in the school timetable\n user . % Also, a user class\n\ninhibit timetable . % Inherit from the timetable class\n\npublic methods\n print / 0 , % Print the complete timetable\n % from the pupil's viewpoint\n print_period / 1 . % Print the pupil's timetable\n % for a specific period\n\n% METHOD : print/0\n% COMMENT: Print the complete timetable from the\n% pupil's viewpoint\n\nprint :-\n isa_class,\n !,\n nl, write( 'FORM TIMETABLE ...' ), nl, nl,\n all instance self <- print, nl.\n\nprint :-\n isa_instance,\n write( 'FORM: ' ), write( mnemonic ), nl,\n all instance period <- print_form( self ), nl.\n\n% METHOD : print_period/1\n% COMMENT: Print the pupil’s timetable for a\n% specific period\n\nprint_period( Period ) :-\n timetable <- filled_entry( self, Period, Teacher, Subject ),\n !,\n write( mnemonic self ), write( ':' ),\n write( mnemonic Teacher ), write( ' teaches ' ),\n write( mnemonic Subject ), nl.\n\nprint_period( _ ) :-\n write( mnemonic self ), write( ':' ), nl.\n\nend form.\n\nThe \"period\" Class\n\n% General attributes & methods for all periods\n\nclass period .\n\n% DECLARATIONS\n\ncategory\n school , % A class in the school timetable\n user . % Also, a user class\n\ninherit\ntimetable . % Inherit from the timetable class\n\npublic methods\n print / 0 , % Print complete timetable\n % from the period viewpoint\n print_teacher / 1 , % Print entry for a specific\n % teacher in this period\n print_form / 1 , % Print entry for a specific\n % form in this period\n print_subject / 1 . % Print entry for a specific\n % subject in this period\n% METHOD: print/0\n% COMMENT: Print the complete timetable from the period viewpoint\n\nprint :-\n isa_class,\n !,\n nl, write( 'PERIOD TIMETABLE ...' ), nl, nl,\n all instance self <- print, nl.\n\nprint :-\n isa_instance,\n write( 'PERIOD: ' ), write( mnemonic ), nl,\n all instance form <- print_period( self ), nl.\n\n% METHOD: print_teacher/1\n% COMMENT: Print the timetable entry for a specific teacher in this period\n\nprint_teacher( Teacher ) :-\n timetable <- filled_entry( Form, self, Teacher, Subject ),\n !,\n write( mnemonic self ), write( ': teach ' ),\n write( mnemonic Subject ), write( ' to ' ),\n write( mnemonic Form ), nl.\n\nprint_teacher( _ ) :-\n write( mnemonic self ), write( ':' ), nl.\n\n% METHOD: print_form/1\n% COMMENT: Print the timetable entry for a specific form in this period\n\nprint_form( Form ) :-\n timetable <- filled_entry( Form, self, Teacher, Subject ),\n !,\n write( mnemonic self ), write( ': ' ),\n write( mnemonic Teacher ), write( ' teaches ' ),\n write( mnemonic Subject ), nl.\n\nprint_form( _ ) :-\n write( mnemonic self ), write( ':' ), nl.\nChapter 6 - A Case Study In Resource Management\n\n% METHOD : print_subject/1\n% COMMENT: Print the timetable entry for a specific subject in this period\nprint_subject( Subject ) :-\n timetable <- filled_entry( Form, self, Teacher, Subject ),\n write( mnemonic self ), write( ': ' ),\n write( mnemonic Form ), write( ' taught by ' ),\n write( mnemonic Teacher ), nl,\n fail.\n\nprint_subject( _ ).\n\nend period.\n\nThe “teacher” Class\n\n% General attributes & methods for all teachers\n\nclass teacher .\n\n% DECLARATIONS\n\ncategory\n school , % A class in the school timetable\n user . % Also, a user class\n\ninherit\ntimetable . % Inherit from the timetable class\n\npublic instance attributes\n freetime = [ ] , % Teachers normally work very hard!\n subjects.\n\npublic methods\n teach_period // 0 , % A period for which the teacher can be assigned\n teach_subject // 0 , % A subject which the teacher can teach\n print / 0 . % Print the complete timetable\n\n% from the teacher viewpoint\n\n% DEFINITIONS\n\nChapter 6 - A Case Study In Resource Management\n\n% METHOD : teach_period//0\n% COMMENT: A period for which the teacher can be assigned\n\nteach_period = P :-\n\\+ member( P, @freetime ).\n\n% METHOD : teach_subject//0\n% COMMENT: A subject which the teacher can teach\n\nteach_subject = S :-\nmember( S, @subjects ).\n\n% METHOD : print/0\n% COMMENT: Print the complete timetable from the teacher viewpoint\n\nprint :-\n isa_class,\n !,\n nl, write( 'TEACHER TIMETABLE ...' ), nl, nl,\n all instance self <- print,\n nl.\n\nprint :-\n isa_instance,\n write( 'TEACHER: ' ), write( mnemonic ), nl,\n all instance period <- print_teacher( self ), nl.\n\nend teacher.\n\nThe \"subject\" Class\n\n% General attributes & methods for all subjects\n\nclass subject .\n\n% DECLARATIONS\n\nProlog++ Reference\ncategory\n school , % A class in the school timetable\n user . % Also, a user class\n\ninherit\ntimetable . % Inherit from the timetable class\n\npublic methods\n print / 0 . % Print the complete timetable\n % from the subjects' viewpoints\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% DEFINITIONS\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n% METHOD : print/0\n% COMMENT: Print the complete timetable from the\n% subject viewpoint\n%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n\nprint :-\n isa_class,\n !,\n nl, write( 'SUBJECT TIMETABLE ...' ), nl, nl,\n all instance self <- print, nl.\n\nprint :-\n isa_instance,\n write( 'SUBJECT: ' ), write( mnemonic ), nl,\n all instance period <- print_subject( self ), nl.\n\nend subject.\n\nThe Output\nThe same timetable was constructed twice with different degrees of effort when trying to\nresolve conflicts. By increasing the effort it was possible to fully complete the timetable.\n\nSetting Up The Timetable\nThe setup phase creates the timetable objects with their individual characteristics.\n\n:- timetable <- setup .\n\nCreate form : first_year\nCreate form : second_year\nCreate form : third_year\nCreate form : fourth_year\nCreate period : 1\nCreate period : 2\nCreate period : 3\nCreate period : 4\nCreate period : 5\nCreate teacher : nicky\nCreate teacher : brian\nCreate teacher : dave\nCreate teacher : clive\nCreate teacher : diane\nCreate teacher : phil\nCreate subject : maths\nCreate subject : music\nCreate subject : french\nCreate subject : prolog\nCreate subject : biology\nCreate subject : prolog++\nCreate subject : accountancy\n\nLess Effort\n\nIn this run the algorithm searches up to 2 levels deep when trying to resolve conflicts. As a result of this restriction it was not possible to complete the timetable.\n\n?- timetable <- make( 2 ).\n\n+ first_year - 1 - brian - maths\n+ first_year - 2 - nicky - french\n+ first_year - 3 - nicky - biology\n+ first_year - 4 - brian - music\n+ first_year - 5 - diane - accountancy\n+ second_year - 1 - dave - maths\n+ second_year - 2 - brian - music\n+ second_year - 3 - diane - accountancy\n+ second_year - 4 - clive - french\n+ second_year - 5 - nicky - biology\n+ third_year - 1 - clive - french\n+ third_year - 2 - dave - maths\n+ third_year - 3 - brian - music\n+ third_year - 4 - phil - prolog++\nSwap teacher ...\n- second_year - 5 - nicky - biology\n+ second_year - 5 - phil - prolog++\n+ third_year - 5 - nicky - biology\n+ fourth_year - 1 - diane - accountancy\n+ fourth_year - 2 - phil - maths\nSwap subject ...\n- first_year - 1 - brian - maths\n+ first_year - 1 - phil - prolog++\nSwap teacher ...\n - first_year - 3 - nicky - biology\n + first_year - 3 - dave - maths\n + fourth_year - 3 - nicky - french\n + fourth_year - 5 - brian - music\n\nThe partially completed timetable is ...\n\n`:-- timetable <-- print .\n\nFORM TIMETABLE ...\n\nFORM: first_year\n 1: phil teaches prolog++\n 2: nicky teaches french\n 3: dave teaches maths\n 4: brian teaches music\n 5: diane teaches accountancy\n\nFORM: second_year\n 1: dave teaches maths\n 2: brian teaches music\n 3: diane teaches accountancy\n 4: clive teaches french\n 5: phil teaches prolog++\n\nFORM: third_year\n 1: clive teaches french\n 2: dave teaches maths\n 3: brian teaches music\n 4: phil teaches prolog++\n 5: nicky teaches biology\n\nFORM: fourth_year\n 1: diane teaches accountancy\n 2: phil teaches maths\n 3: nicky teaches french\n 4:\n 5: brian teaches music\n\netc.\n\nMore Effort\n\nIn this run the effort was increased to searching 5 levels deep and as a result it was able to complete the timetable.\n\n`:-- timetable <-- make( 5 ) .\n\n82 Prolog++ Reference\nThe completed timetable is ...\n:- timetable <- print .\n\nFORM TIMETABLE ...\n\nFORM: first_year\n1: phil teaches prolog++\n2: nicky teaches french\n3: dave teaches maths\n4: clive teaches prolog\n5: brian teaches music\n\nFORM: second_year\n1: clive teaches prolog\n2: brian teaches music\n3: diane teaches accountancy\n4: dave teaches maths\n5: phil teaches prolog++\n\nFORM: third_year\n1: diane teaches accountancy\n2: dave teaches maths\n3: brian teaches music\n4: phil teaches prolog++\n5: nicky teaches biology\n\nFORM: fourth_year\n1: brian teaches music\n2: phil teaches maths\n3: nicky teaches french\n4: brian teaches music\n5: diane teaches accountancy\n\nPERIOD TIMETABLE ...\n\nPERIOD: 1\nfirst_year: phil teaches prolog++\nsecond_year: clive teaches prolog\nthird_year: diane teaches accountancy\nfourth_year: brian teaches music\n\nPERIOD: 2\nfirst_year: nicky teaches french\nsecond_year: brian teaches music\nthird_year: dave teaches maths\nfourth_year: phil teaches maths\n\nPERIOD: 3\nfirst_year: dave teaches maths\nsecond_year: diane teaches accountancy\nthird_year: brian teaches music\nfourth_year: nicky teaches french\n\nPERIOD: 4\nfirst_year: clive teaches prolog\nsecond_year: dave teaches maths\nthird_year: phil teaches prolog++\nfourth_year: brian teaches music\n\nPERIOD: 5\nfirst_year: brian teaches music\nsecond_year: phil teaches prolog++\nthird_year: nicky teaches biology\nfourth_year: diane teaches accountancy\n\nTEACHER TIMETABLE ...\n\nTEACHER: nicky\n1:\n2: teach french to first_year\n3: teach french to fourth_year\n4:\n5: teach biology to third_year\n\nTEACHER: brian\n1: teach music to fourth_year\n2: teach music to second_year\n3: teach music to third_year\n4: teach music to fourth_year\n5: teach music to first_year\n\nTEACHER: dave\n1:\n2: teach maths to third_year\n3: teach maths to first_year\n4: teach maths to second_year\n5:\n\nTEACHER: clive\n1: teach prolog to second_year\n2:\n3:\n4: teach prolog to first_year\n5:\n\nTEACHER: diane\n1: teach accountancy to third_year\n2:\n3: teach accountancy to second_year\n4:\n5: teach accountancy to fourth_year\n\nTEACHER: phil\n1: teach prolog++ to first_year\n2: teach maths to fourth_year\n3:\n4: teach prolog++ to third_year\n5: teach prolog++ to second_year\n\nSUBJECT TIMETABLE ...\n\nSUBJECT: maths\n2: third_year taught by dave\n2: fourth_year taught by phil\n3: first_year taught by dave\n4: second_year taught by dave\n\nSUBJECT: music\n1: fourth_year taught by brian\n2: second_year taught by brian\n3: third_year taught by brian\n4: fourth_year taught by brian\n5: first_year taught by brian\n\nSUBJECT: french\n2: first_year taught by nicky\n3: fourth_year taught by nicky\n\nSUBJECT: prolog\n1: second_year taught by clive\n4: first_year taught by clive\n\nSUBJECT: biology\n5: third_year taught by nicky\n\nSUBJECT: prolog++\n1: first_year taught by phil\n4: third_year taught by phil\n5: second_year taught by phil\n\nSUBJECT: accountancy\n1: third_year taught by diane\nChapter 6 - A Case Study In Resource Management\n\n3: second_year taught by diane\n5: fourth_year taught by diane\nChapter 7 - A Case Study In Database Management\n\nThis case study will investigate the application of Prolog++ to small, active databases. Prolog++ inherits all of the database features of Prolog, which can be thought of as a deductive, relational database manager. It augments this with the ability to structure the database as an instance hierarchy, using inheritance to avoid duplication and redundant values.\n\nSince Prolog++, like Prolog, keeps everything resident in memory, it is not recommended for large scale databases. The new generation of DBMS’s now emerging, such as Sybase, are incorporating many aspects of OOPS. This is not to say, however, that small databases are not interesting. There are a plethora of small to medium sized businesses that are demanding smart, compact databases. An example of such an application is outlined in the following sections.\n\nThe Problem\n\nBill Hobbs is a stocktaker for the restaurant and public house trade. He has many clients that he visits on a regular basis to count the stock on hand. Using the information gathered, Bill generates a report of the client’s trading for that period, including such results as the total actual sales, the expected sales and in particular any shortfall or excess. The service provided by Bill Hobbs is very important to each client, as it keeps a regular check on any pilfering by the staff, and also provides valuable information as to the profitability of the business.\n\nThis is a very repetitive and laborious task, and since most restaurants and public houses share the same characteristics it is highly amenable to computerisation. An analysis of the problem showed that it was also suited to an object-oriented representation.\n\nThe stock carried by restaurants and public houses falls neatly into a hierarchy of sections, lines and actual stock entries. Broadly, the stock can be divided into beers, wines and spirits (the sections), which are further divided into lines such as draught beers, bottled beers, table wines, fortified wines, brandies, whiskeys, etc.. These demarcations are very important to the client as they give a complete breakdown of his trading patterns.\n\nEach individual item of stock has a fixed set of values, including its cost and selling prices, its current stock level, and others. Each of the lines, sections and overall stock have two important totals, which are its cumulative purchases and its cumulative sales.\n\nValue added tax (VAT) applies to all the business carried out. It is normal practice that cost prices are given exclusive of VAT, and that retail prices are given inclusive of VAT.\nThe Classes\nIt was decided to structure the stock as a class hierarchy which completely mirrors the client’s view.\n\n```\nstock\n\nbeer\n\nspirit\n\nwine\n\ndraught beer bottled beer\n\ntable wine fortified wine\n```\n\nThe “stock” Class\n\nThe stock class represents all the kinds of stock from individual lines such as Guinness to groups such as draughts beers and beers in general.\n\n```\n%CLASS : stock\n%COMMENT: The generic class for all kinds of stock\n\nclass stock .\n\n%DECLARATIONS\n\ncategories\n user ,\n stock . % A class in the stock database\n\npublic methods\n setup / 0 , % Set up the stock instances\n report / 0 , % Generate a stock report\n listings / 0 , % Listings of sub-groups & individual lines\n listing / 0 , % Listing of a single line\n summaries / 0 . % Summaries of all sub-groups\n```\nprivate methods\n setup / 1,\n listings / 1,\n summaries / 1,\n total_up_classes / 1,\n total_up_instances / 1,\n type // 0,\n apply_vat // 1.\n\nIn addition to the primary methods setup/0 and report/0, certain other methods need to be made public so that they are accessible to the group classes. This is because messages such as listings/0 are sent from outside to, for instance, the beer class.\n\nThe stock attributes are split into those which pertain to the group classes and those which pertain to individual instances of lines.\n\nclass attributes\n total_costs_excluding_vat is 0,\n total_sales_including_vat is 0.\n\nprivate class attributes\n total_costs_including_vat is apply_vat( \n total_costs_excluding_vat\n ),\n profit_or_loss is total_sales_including_vat - total_costs_including_vat.\n\npublic instance attributes\n costs_excluding_vat is bought * buying_price_excluding_vat,\n sales_including_vat is sold * selling_price_including_vat.\n\nprivate instance attributes\n name = self,\n buying_price_excluding_vat is 0,\n selling_price_including_vat is 0,\n previous_stock is 0,\n current_stock is 0,\n purchases is 0,\n credits is 0,\n bought is purchases - credits,\n sold is previous_stock -\n current_stock +\n bought,\n costs_including_vat is apply_vat( costs_excluding_vat ).\nDEFINITIONS\n\n% METHOD: setup/0\n% COMMENT: Set up the stock instances according to the type of the\n% stock class\n\nsetup :-\n setup( @type ).\n\nsetup( group ) :-\n all sub_class self <- setup .\n\nsetup( lines ) :-\n delete_all,\n forall line( Name, Buy, Sell, Old, New, Purchases, Credits )\n do create( _, [\n name = Name,\n buying_price_excluding_vat is Buy,\n selling_price_including_vat is Sell,\n previous_stock is Old,\n current_stock is New,\n purchases is Purchases,\n credits is Credits\n ]).\n\nreport :-\n write( '-----------------------------------------------------------' ), nl,\n write( '| Buying | Selling | Previous | Current | Credit |' ), nl,\n write( '| Price | Price | Stock | Stock | Purchase |' ), nl,\n write( '-----------------------------------------------------------' ), nl,\n listings, nl,\n write( '-----------------------------------------------------------/' ), nl,\n nl,\n write( '-------------------------------------------------------' ), nl,\n write( '| Costs | Costs | Sales | Profit/Loss |' ), nl,\n write( '| (Excl VAT) | (Incl VAT) | (Incl VAT) | (Incl VAT) |' ), nl,\n write( '-------------------------------------------------------|' ), nl,\n summaries,\n write( '\\-------------------------------------------------------/' ), nl,\n nl.\n\nlistings :-\n listings( @type ).\n\nsummaries :-\n summaries( @type ),\n summary .\n% Case 1) This is a general class of stock with further\n% sub-classes\n\nlistings( group ) :-\n all sub_class self <- listings.\n\nsummaries( group ) :-\n all sub_class self <- summaries,\n total_costs_excluding_vat := 0,\n total_sales_including_vat := 0,\n total_up_classes( all sub_class self ).\n\ntotal_up_classes( [] ).\n\ntotal_up_classes( [Class|Classes] ) :-\n total_costs_excluding_vat += Class@total_costs_excluding_vat,\n total_sales_including_vat += Class@total_sales_including_vat,\n total_up_classes( Classes ).\n\n% Case 2) This is a bottom-level class with actual instances %\n\nlistings( lines ) :-\n write( '|\n write( self ), nl,\n all instance self <- listing.\n\nsummaries( lines ) :-\n total_costs_excluding_vat := 0,\n total_sales_including_vat := 0,\n total_up_instances( all instance self ).\n\ntotal_up_instances( [] ).\n\ntotal_up_instances( [Instance|Instances] ) :-\n total_costs_excluding_vat += Instance@costs_excluding_vat,\n total_sales_including_vat += Instance@sales_including_vat,\n total_up_instances( Instances ).\nlisting :-\n write_value( @buying_price_excluding_vat, 9, 2 ),\n write_value( @selling_price_including_vat, 9, 2 ),\n write_value( @previous_stock, 9, 1 ),\n write_value( @current_stock, 9, 1 ),\n write_value( @purchases, 9, 0 ),\n write_value( @credits, 9, 0 ),\n write( '|' ), write( @name ), nl.\n\nsummary :-\n write_value( @total_costs_excluding_vat, 12, 2 ),\n write_value( @total_costs_including_vat, 12, 2 ),\n write_value( @total_sales_including_vat, 12, 2 ),\n write_value( @profit_or_loss, 12, 2 ),\n write( '|' ), write( self ), nl.\n\nwrite_value( Value, Width, Decimals ) :-\n Integer is int( Value ),\n ( Decimals = 0\n -> ( Integer < 10 -> Tab = 6\n ; Integer < 100 -> Tab = 5\n ; Integer < 1000 -> Tab = 4\n ; Tab = 3 )\n ; ( Integer < 10 -> Tab is 5 - Decimals\n ; Integer < 100 -> Tab is 4 - Decimals\n ; Integer < 1000 -> Tab is 3 - Decimals\n ; Tab is 2 - Decimals ) ) ),\n write( '|' ),\n tab( Width+Tab-7 ),\n write( Integer ),\n ( Decimals = 0\n -> true\n ; write( '.' ),\n Fraction is int( (Value - Integer) * (10^Decimals) + 0.5 ) / (10^Decimals),\n write_decimals( Decimals, Fraction ) ),\n write( '|' ).\n\nwrite_decimals( 0, _ ) :- !.\nwrite_decimals( Decimals1, Fraction1 ) :-\n Digit is int( 10 * Fraction1 ),\n write( Digit ),\n Decimals2 is Decimals1 - 1,\n Fraction2 is (10 * Fraction1) - Digit,\n write_decimals( Decimals2, Fraction2 ).\n% METHOD : apply_vat/1\n% COMMENT: Apply VAT to an exclusive amount to give an inclusive\n% amount\napply_vat( Amount ) is Amount * 1.175 .\n\n% METHOD : type/0\n% COMMENT: Determine the type according to whether there are any\n% sub-classes\n\ntype = group :-\n sub_class self = __,\n !.\n\ntype = lines .\n\nend stock .\n\nThe Sections And Lines\n\nThe sections are represented as sub-classes of the generic stock class. The individual\nlines are represented as instances created through the setup/0 method.\n\nclass beer .\n categories stock, user .\n inherits stock .\nend beer .\n\nclass beer_draught .\n categories stock, user .\n inherits beer .\n public method line / 7 .\n line( abbot_ale, 4.20, 8.40, 4.0, 5.0, 11, 0 ).\n line( carlsberg, 4.80, 9.60, 5.0, 2.0, 11, 0 ).\n line( guinness, 5.20, 10.40, 7.0, 4.0, 18, 9 ).\nend beer_draught .\n\nclass beer_bottled .\n categories stock, user .\n inherits beer .\n public method line / 7 .\n line( pale_ale, 8.00, 16.20, 5.0, 3.2, 12, 0 ).\n line( brown_ale, 8.50, 17.40, 7.3, 6.0, 12, 0 ).\nclass wine .\n categories stock, user .\n inherits stock .\nend wine .\n\nclass wine_table .\n categories stock, user .\n inherits wine .\n public method line / 7 .\n line( claret, 1.95, 4.50, 17, 15, 36, 0 ).\n line( chablis, 5.00, 11.50, 22, 16, 48, 12 ).\nend wine_table .\n\nclass wine_fortified .\n categories stock, user .\n inherits wine .\n public method line / 7 .\n line( martini, 3.25, 9.70, 4.2, 2.7, 0, 0 ).\nend wine_fortified .\n\nclass spirit .\n categories stock, user .\n inherits stock .\n public method line / 7 .\n line( brandy, 8.40, 25.20, 2.4, 1.6, 0, 0 ).\n line( whiskey, 7.50, 22.50, 2.3, 3.2, 6, 0 ).\n line( vodka, 6.95, 20.85, 3.5, 4.2, 6, 0 ).\n line( gin, 7.25, 21.75, 4.1, 2.2, 0, 0 ).\nend spirit .\n\nThe Output\n\nThe stock instances are created through the setup/0 method and then a report generated.\n\n?- stock <- setup .\nyes\n\n?- stock <- report .\n\n<table>\n<thead>\n<tr>\n<th>Buying</th>\n<th>Selling</th>\n<th>Previous</th>\n<th>Current</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Price</td>\n<td>Price</td>\n<td>Stock</td>\n<td>Stock</td>\n</tr>\n<tr>\n<td>--------</td>\n<td>--------</td>\n<td>--------</td>\n<td>--------</td>\n</tr>\n<tr>\n<td>beer_draught</td>\n<td>4.20</td>\n<td>8.40</td>\n<td>4.0</td>\n</tr>\n<tr>\n<td>abbot_ale</td>\n<td>4.80</td>\n<td>9.60</td>\n<td>5.0</td>\n</tr>\n<tr>\n<td>carlsberg</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n96 Prolog++ Reference\n### Guinness\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>Cost (Excl VAT)</th>\n<th>Cost (Incl VAT)</th>\n<th>Sales (Incl VAT)</th>\n<th>Profit/Loss (Incl VAT)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Guinness beer</td>\n<td>5.20</td>\n<td>10.40</td>\n<td>7.0</td>\n<td>4.0</td>\n</tr>\n<tr>\n<td>Guinness pale ale</td>\n<td>8.00</td>\n<td>16.20</td>\n<td>5.0</td>\n<td>3.2</td>\n</tr>\n<tr>\n<td>Guinness brown ale</td>\n<td>8.50</td>\n<td>17.40</td>\n<td>7.3</td>\n<td>6.0</td>\n</tr>\n</tbody>\n</table>\n\n### Beer Bottled\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>Cost (Excl VAT)</th>\n<th>Cost (Incl VAT)</th>\n<th>Sales (Incl VAT)</th>\n<th>Profit/Loss (Incl VAT)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Pale Ale beer</td>\n<td>1.95</td>\n<td>4.50</td>\n<td>17.0</td>\n<td>15.0</td>\n</tr>\n<tr>\n<td>Claret beer</td>\n<td>5.00</td>\n<td>11.50</td>\n<td>22.0</td>\n<td>16.0</td>\n</tr>\n<tr>\n<td>Chablis beer</td>\n<td>3.25</td>\n<td>9.70</td>\n<td>4.2</td>\n<td>2.7</td>\n</tr>\n</tbody>\n</table>\n\n### Wine Table\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>Cost (Excl VAT)</th>\n<th>Cost (Incl VAT)</th>\n<th>Sales (Incl VAT)</th>\n<th>Profit/Loss (Incl VAT)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Claret wine</td>\n<td>5.00</td>\n<td>11.50</td>\n<td>22.0</td>\n<td>16.0</td>\n</tr>\n<tr>\n<td>Chablis wine</td>\n<td>5.00</td>\n<td>11.50</td>\n<td>22.0</td>\n<td>16.0</td>\n</tr>\n<tr>\n<td>Martini wine</td>\n<td>8.40</td>\n<td>25.20</td>\n<td>2.4</td>\n<td>1.6</td>\n</tr>\n</tbody>\n</table>\n\n### Spirit\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>Cost (Excl VAT)</th>\n<th>Cost (Incl VAT)</th>\n<th>Sales (Incl VAT)</th>\n<th>Profit/Loss (Incl VAT)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Brandy spirit</td>\n<td>7.50</td>\n<td>22.50</td>\n<td>2.3</td>\n<td>3.2</td>\n</tr>\n<tr>\n<td>Whiskey spirit</td>\n<td>6.95</td>\n<td>20.85</td>\n<td>3.5</td>\n<td>4.2</td>\n</tr>\n<tr>\n<td>Vodka spirit</td>\n<td>7.25</td>\n<td>21.75</td>\n<td>4.1</td>\n<td>2.2</td>\n</tr>\n<tr>\n<td>Gin spirit</td>\n<td>8.40</td>\n<td>25.20</td>\n<td>2.4</td>\n<td>1.6</td>\n</tr>\n</tbody>\n</table>\n\n---\n\n### Costs Summary\n\n- **Guinness beer**: £145.80 (Excl VAT) / £171.30 (Incl VAT)\n- **Pale Ale beer**: £198.00 (Excl VAT) / £232.65 (Incl VAT)\n- **Brown Ale beer**: £343.80 (Excl VAT) / £403.97 (Incl VAT)\n- **Claret wine**: £250.20 (Excl VAT) / £293.98 (Incl VAT)\n- **Chablis wine**: £14.55 (Excl VAT) / £14.55 (Incl VAT)\n- **Martini wine**: £250.20 (Excl VAT) / £293.98 (Incl VAT)\n- **Brandy spirit**: £680.70 (Excl VAT) / £799.81 (Incl VAT)\n- **Whiskey spirit**: £86.70 (Excl VAT) / £101.86 (Incl VAT)\n- **Vodka spirit**: £680.70 (Excl VAT) / £799.81 (Incl VAT)\n- **Gin spirit**: £86.70 (Excl VAT) / £101.86 (Incl VAT)\n\n**Total Costs**: £1,693.50 (Excl VAT) / £1,982.36 (Incl VAT)\n\n**Total Sales**: £4,887.90 (Incl VAT)\n\n**Profit/Loss**: £994.47 (Incl VAT)\nChapter 8 - A Case Study In Fault Diagnosis\n\nThis case study will investigate the application of Prolog++ to the diagnosis of faults. It is intended to illustrate the technique of progressively sending messages through the hierarchy, starting from at a general level and gradually moving down to classes at the lower, more specific levels.\n\nThe hierarchy is used to represent the implicit relationships between different classes of faults.\n\nThe Problem\nWe would like to represent the causal-effect relationship between faults and symptoms. The particular domain, that of car maintenance, was chosen to illustrate the techniques in layman terms. Everybody is familiar, to a greater or lesser degree, with the problems that can occur with automobiles.\n\nThe crucial factor in fault diagnosis is being able to quickly pinpoint the general area of the problem, before focusing in on the root cause. Identifying general aspects of the problem can avoid going down blind alleys, and more importantly avoids asking the user seemingly irrelevant questions.\n\nFor the domain of car maintenance, an automobile can be dissected into several problem areas such as the fuel system, mechanical faults and electrical faults. Associated with each area is a collection of faults which may occur, and the symptoms which they cause. Some of the symptoms may be contradictory, in the sense that two symptoms cannot possibly occur simultaneously.\n\nThe Classes\nFrom the above discussion two quite separate types of instance can be identified. The first concerns itself with fault diagnosis, including the ability to move from general terms down to specific terms. The second deals with the problem domain, in terms of the causal-effect relationships between actual faults and exhibited symptoms.\n\nThe following diagram illustrates a hierarchy for identifying faults in automobiles. At the topmost level is the faults class containing the algorithm for finding faults, and which is inherited by all of the other classes in the hierarchy. At any point, however, a class has the option to override the default search algorithm with one that is specialized for its problem area.\nThe following sections define the protocol (attributes, methods and functions) for the faults instance and for the domain specific objects.\n\n**The Domain Classes**\n\n```prolog\nclass mechanical.\ninherit fault.\nend mechanical.\n\nclass engine.\ninherit mechanical.\nend engine.\n\nclass cylinders.\ninherit engine.\nend cylinders.\n\nclass fuel_system.\ninherit fault.\nend fuel_system.\n\nclass electrical.\ninherit fault.\nend electrical.\n\nclass lights.\ninherit electrical.\nend lights.\n```\nclass starting.\ninherit electrical.\nend starting.\n\nclass starter_motor.\ninherit starting.\nend starter_motor.\n\nclass sparking.\ninherit starting.\nend sparking.\n\nclass plugs.\ninherit sparking.\nend plugs.\n\nclass distributor.\ninherit sparking.\nmethod fault // 1.\n fault( f1001 ) = 'Condensation in the distributor cap'.\n fault( f1002 ) = 'Faulty distributor arm'.\n fault( f1003 ) = 'Worn distributor brushes'.\nmethod symptom // 1.\n symptom( s1001 ) = 'The starter motor turns but the engine\ndoes not fire'.\n symptom( s1002 ) = 'The engine has difficulty starting'.\n symptom( s1003 ) = 'The engine cuts out shortly after\nstarting'.\n symptom( s1004 ) = 'The engine cuts out at speed'.\nmethod effect // 1.\n effect( f1001 ) = s1001.\n effect( f1002 ) = s1001.\n effect( f1002 ) = s1004.\n effect( f1003 ) = s1002.\n effect( f1003 ) = s1003.\nmethod contrary / 2.\n contrary( s1002, s1001 ).\n contrary( s1003, s1001 ).\nend distributor.\n\nThe \"fault\" Class\n\n% >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n% CLASS : fault\n% COMMENT: How to search for and report faults\n% >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n\nclass fault.\n\n100Prolog++ Reference\ncategory fault , % A class in the fault diagnosis\n user .\n\npublic methods\n findall / 0 . % Find and report all possible faults\n\n% METHOD : findall/0\n% COMMENT: Find and print all possible faults\n\nfindall :-\n dynamic( told_by_user / 2 ),\n forall ( %\n ( Where = self\n ; Where = descendant_class ),\n Where <- find( Fault )\n )\n do (%\n write( 'Location : ' ), write( Where ), nl,\n write( 'Possible Fault: ' ), write( Fault ), nl, nl\n ).\n\n% METHOD : find/1\n% COMMENT: Find a possible fault for some class\n% Explicit use of 'self' to avoid any early bindings!\n\nfind( Fault ) :-\n public( fault // 1 ),\n Fault = self@fault( FaultNumber ),\n forall SymptomNumber = self@effect( FaultNumber )\ndo exhibited( SymptomNumber ).\n% METHOD : exhibited/2\n% COMMENT: Ask the user whether or not the symptom is exhibited & remember\n\nexhibited( SymptomNumber ) :-\n told_by_user( SymptomNumber, Reply ),\n !,\n Reply = yes.\n\nexhibited( SymptomNumber ) :-\n cat( [self@symptom(SymptomNumber),'?'], Question, _ ),\n ( yesno( Question ) -> Reply = yes ; Reply = no ),\n asserta( told_by_user( SymptomNumber, Reply ) ),\n Reply = yes,\n forall ( self <- contrary( SymptomNumber, ContrarySymptom )\n ; self <- contrary( ContrarySymptom, SymptomNumber ) )\n do asserta( told_by_user( ContrarySymptom, no ) ).\n\nend fault.\n\nThe Output\nThe following outputs were taken from two fault diagnosis sessions.\n\n?- faults <- findall .\n\n<table>\n<thead>\n<tr>\n<th>Question</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>! Starter motor turns, but engine does not fire ?</td>\n</tr>\n<tr>\n<td>yes</td>\n</tr>\n<tr>\n<td>no</td>\n</tr>\n</tbody>\n</table>\n\nLocation : distributor\nPossible Fault : Condensation in distributor cap\nLocation : distributor\nPossible Fault : Faulty distributor arm\n\nNo more solutions\n\n?- faults <- findall .\nLocation : distributor\nPossible Fault : Worn distributor brushes\n\nNo more solutions\nPart 3 - Technical Specification Of Prolog++\nChapter 9 - The Prolog++ Language\n\nIn this section we present the language of Prolog++. A formal definition of the syntax can be found in the appendices.\n\nPrograms\nA Prolog++ program is a collection of Prolog++ classes which communicate with each other by sending messages. It is similar to a Prolog program defined as a collection of modules which communicate by calling each other’s procedures.\n\nEach class definition in a Prolog++ program is delimited by open and close statements. The open/close statements are of the form :-\n\n```\nclass “Name of Class”.\nend “Name of Class”.\n```\n\nwhere exactly the same class name is mentioned in both statements. As with Prolog, a full stop (.) is used to terminate each and every statement. Indeed, all statements must conform to the same syntactic constraints as Prolog clauses.\n\nProgram Statements\nThe program statements occurring between the open and close statements define the structure and contents of a class. They fall into two distinct categories; i) code statements which define how various kinds of messages are handled, and ii) meta statements which talk about the class and its methods.\n\nThe code statements can be further divided into procedural and functional method definitions. The meta statements cover the areas of class hierarchies, part-of hierarchies, encapsulation and dynamic data. These statements can occur in any order whatsoever, with code and meta information freely intermixed.\n\nLogical Variables\nProlog++ uses the same terminology for logical variables as Prolog. Unquoted atoms beginning with a capital letter (e.g. Element, Stack) or beginning with an underscore (e.g. _1, _xyz) are named variables. An underscore by itself denotes an anonymous variable whose instantiated value is not important.\n\n---\n\n1 See the appendices for the syntactic operators declared by Prolog++.\nInstance Variables\n\nProlog++ provides two instance variables represented by specially reserved words of the language. They can be used in any context whatsoever, having the same syntactic status as any other Prolog term.\n\nThe instance variables provided by Prolog++ are:\n\nself substituted at run-time by the instance, or class, to which the message being handled was originally sent\n\nsuper substituted at compile-time by the super class of the class in which it textually occurs\n\nThe Is-A Hierarchy\n\nThe is-a hierarchy of Prolog++ relates specific classes with more general classes through the mechanism of inheritance.\n\nIs-A Declarations\n\nThe is-a relationship between classes is expressed within each class definition by declaring its super or parent class(es).\n\n```prolog\nclass stack.\n inherits buffer. % inherits all characteristics of buffers\n...\nend stack.\n\nclass queue_with_statistics.\n inherits queue, % inherits from general queues\n buffer_with_statistics. % as well as statistical buffers\n...\nend queue_with_statistics.\n```\n\nA strict hierarchy is one in which all classes have either a single super class or none at all. Such a hierarchy is said to exhibit singular inheritance. Hierarchies in which at least one class has several super classes is said to exhibit multiple inheritance.\n\nAccessing The Is-A Hierarchy\n\nThe is-a hierarchy can be navigated by referring to super, sub, ancestral and descendant classes. This is expressed by a collection of reserved words.\n\nsuper_class the/a super or parent class\n\nsub_class a sub or child class\n\nancestor_class a super class (parent), or a super-super class (grandparent), etc.\n\ndescendant_class a sub class (child), or a sub-sub class (grandchild), etc.\nThe Part-Of Hierarchy\n\nThe part-of hierarchy of Prolog++ relates class instances with one another such that they can be thought of either collectively or individually.\n\nThe creation of a complex object such as a bicycle may involve the creation of several parts, including wheels, a frame and handlebars. These in turn may involve the creation of further sub-parts such as spokes and rims.\n\nPart-Of Declarations\n\nThe part-of relationship between class instances is expressed within each class definition by declaring its component parts.\n\nclass bicycle.\n parts frame, wheel * 2, seat, handle_bars.\nend bicycle.\n\nclass unicycle.\n inherit bicycle.\n parts wheel, handle_bars * 0.\nend unicycle.\n\nclass tandem.\n inherit bicycle.\n parts seat * 2, handle_bars * 2.\nend tandem.\n\nThe parts declaration can be inherited. For example, in addition to the 2 seats and 2 sets of handle-bars a tandem will inherit a frame and 2 wheels from the bicycle class. The unicycle forces the handle-bars not to be inherited by explicitly declaring 0 for that part.\n\nCreating Composite Instances\n\nWhenever a new instance of a class is created the parts declaration of that class is inspected and the corresponding instances of the sub-parts are created.\n\nFor example, consider the various cycle classes above and assume that the others are all sub-classes of cycle_component.\n\nclass cycle_component.\n\npublic method when_created/0.\nwhen_created :-\n write( 'Created: ' ),\n write( self ),\n nl.\nend cycle_component.\n\n108 Prolog++ Reference\nThe creation of a new bicycle will involve the creation of a frame, two wheels, a seat and a set of handle-bars.\n\n?- bicycle <- create(C).\n\nCreated: frame|163844\nCreated: wheel|163824\nCreated: wheel|163834\nCreated: seat|163846\nCreated: handle_bars|163848\n\nC = (bicycle|163823)\n\nwhereas the creation of a unicycle will only create a wheel, a frame and a seat in addition to the unicycle itself.\n\n?- unicycle <- create(C).\n\nCreated: wheel|181366\nCreated: frame|181376\nCreated: seat|181378\n\nC = (unicycle|181365)\n\nNow consider that a wheel is actually made from a rim and some spokes.\n\nclass wheel.\n\n inherit cycle_component.\n parts rim, spoke * @spokes.\n class attribute spokes is 3.\nend wheel.\n\nclass rim.\n\n inherit cycle_component.\nend rim.\n\nclass spoke.\n\n inherit cycle_component.\nend spoke.\n\nThe creation of a unicycle will now create a wheel, a frame and a seat as before, but in addition the wheel will be further sub-divided into a rim and three spokes.\n\n?- unicycle <- create(C).\n\nCreated: wheel|198130\nCreated: rim|198132\nCreated: spoke|198134\nCreated: spoke|198136\nCreated: spoke|198138\nAccessing The Part-Of Hierarchy\n\nThe part-of hierarchy can be navigated by referring to sub parts, super parts and the top-most ancestral part. This is expressed by a collection of reserved words.\n\n- **composite_part** — the top-most instance in this part-of hierarchy.\n- **super_part** — the super or parent instance which this is a part of.\n- **sub_part** — a sub or child part of this instance.\n- **#** — a specifically numbered sub part.\n\nFor example, the relationship between the various components for the unicycle created above can be described by the following statements.\n\n- `unicycle|198129` is the composite_part of `wheel|198130`\n- `unicycle|198129` is the composite_part of `rim|198132`\n- `unicycle|198129` is the composite_part of `spoke|198134`\n- `unicycle|198129` is the composite_part of `spoke|198136`\n- `unicycle|198129` is the composite_part of `frame|198140`\n- `unicycle|198129` is the composite_part of `seat|198142`\n\n- `unicycle|198129` is the super_part of `wheel|198130`\n- `wheel|198130` is the super_part of `rim|198132`\n- `wheel|198130` is the super_part of `spoke|198134`\n- `wheel|198130` is the super_part of `spoke|198136`\n- `wheel|198130` is the super_part of `spoke|198138`\n- `unicycle|198129` is the super_part of `frame|198140`\n- `unicycle|198129` is the super_part of `seat|198142`\n\n- `wheel|198130` is a sub_part of `unicycle|198129`\n- `rim|198132` is a sub_part of `wheel|198130`\n- `spoke|198134` is a sub_part of `wheel|198130`\n- `spoke|198136` is a sub_part of `wheel|198130`\n- `spoke|198138` is a sub_part of `wheel|198130`\n- `frame|198140` is a sub_part of `unicycle|198129`\n- `seat|198142` is a sub_part of `unicycle|198129`\n\n- `wheel|198130` is wheel#1 of `unicycle|198129`\n- `rim|198132` is rim#1 of `wheel|198130`\n- `spoke|198134` is spoke#1 of `wheel|198130`\n- `spoke|198136` is spoke#2 of `wheel|198130`\n- `spoke|198138` is spoke#3 of `wheel|198130`\nAttributes\nThe attributes of a class correspond to the characteristics of the entity which it represents. They may or may not have default values.\n\nAttribute Declarations\nAttributes can be split into those which relate to individual instances of the class and those for the overall class itself. Each of these can be declared as private or public attributes.\n\nprivate instance attributes ...\npublic instance attributes ...\nprivate class attributes ...\npublic class attributes ...\n\nA public attribute is one whose value is accessible from outside the class in which it occurs, whereas a private attribute can only be accessed from within. In either case, the attribute’s value can only be changed from within the class.\n\npublic class attribute\nsmallest . % the smallest instance in\n% this class; no default value\n\nprivate instance attributes\ncontents = [], % default contents is empty list\nsize is 0 , % the default size is zero\ncumulative_size inherited . % cumulative size is inherited\n% from an ancestor class\n\nAn instance attribute is one which relates to an individual instance of a class. For example, consider a class representing customers of a bank. One attribute is the amount of work necessary to service each individual customer.\n\nA class attribute is one which relates to the overall class itself. For example, an attribute of a class of customer queues may be a pointer to the smallest queue. Each attribute in the declaration list can be assigned an explicit default value (arithmetic or non-arithmetic), an inherited default value or have no default.\n\nAssignment Of Attributes\nThere are two forms of attribute assignment in Prolog++, one which activates procedures and the other which does not. An assignment which invokes the daemon manager is referred to as a noisy assignment, and one which merely performs the update and does nothing else is referred to as a quiet assignment. They both have the same basic form:\n“Name of Attribute” := “New Value”\n\n“Name of Attribute” ::= “New Value”\n\nwhere := is an example of a noisy assignment operator and ::= is an example of a quiet assignment operator.\n\nclass stack.\n\ncontents = [].\nsize is 0.\n\npush( Element ) :-\n contents := [ Element | contents ],\n size +== 1.\n\n...\n\nend stack.\n\n**Noisy Assignment**\n\nA noisy assignment of a new value to an attribute will invoke the daemon manager in two ways. Before the assignment is performed any constraints will be checked. Immediately after the assignment has been confirmed all reactionary daemons will be invoked\\(^2\\).\n\n**Quiet Assignment**\n\nA quiet assignment will not invoke the daemon manager at all, but will merely perform the update.\n\n---\n\n\\(^2\\)See the chapter on Prolog++ : Daemons for a full description.\nAssignment Operators\n\nThere are five different assignment operators :-\n\n<table>\n<thead>\n<tr>\n<th>Noisy</th>\n<th>Quiet</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>:=</td>\n<td>==</td>\n<td>Replace any current value with the incoming value</td>\n</tr>\n<tr>\n<td>+=</td>\n<td>==</td>\n<td>Add (arithmetic) the incoming value to the current value or default value and assign the result to the attribute</td>\n</tr>\n<tr>\n<td>-=</td>\n<td>==</td>\n<td>Subtract (arithmetic) the incoming value from the current value or default value and assign the result to the attribute</td>\n</tr>\n<tr>\n<td>*=</td>\n<td>==</td>\n<td>Multiply (arithmetic) the current value or default value by the incoming value and assign the result to the attribute</td>\n</tr>\n<tr>\n<td>/=</td>\n<td>==</td>\n<td>Divide (arithmetic) the current value or default value by the incoming value and assign the result to the attribute</td>\n</tr>\n</tbody>\n</table>\n\nChaining Attributes Together\n\nIt is possible that the values of attributes are the names/handles of other objects. That is, attributes can act as pointers to other objects.\n\n```prolog\nclass employee_record.\npublic instance attribute address.\nwhen_created :-\n address_record <- create(AddressRecord),\n address := AddressRecord.\nset_city( City ) :-\n @address <- set_city( City ).\nget_city( City ) :-\n City = @address@city.\nend employee_record.\nclass address_record.\npublic instance attribute city='London'.\nset_city( City ) :-\n city := City.\nend address_record.\n```\n\nBy chaining together attributes with the @ operator the city where an employee lives can be accessed without directly referring to `address_record`.\n\n```prolog\n?- employee_record <- create(E),\n E <- get_city(C1),\n E <- set_city('Oxford'),\n E <- get_city(C2).\n\nE = ...,\nC1=‘London’, C2=‘Oxford’\n```\n\n\nProcedural Methods\n\nA class’s methods define how and when messages can be handled, either sent directly to it or passed up the hierarchy by the inheritance mechanism from a descendant class.\n\nProcedural Declarations\n\nThe notion of encapsulation in Prolog++ applies not only to data (the attributes of an instance or class) but equally to its algorithms. That is, some of the internal routines used by a class can be hidden from the outside world. This is rather like a module system, which exports a certain collection of visible routines whilst hiding its innermost workings.\n\nMethods can be declared either as public or private, and involve both the name of the method and the number of parameters (its arity).\n\nclass stack.\npublic methods\n push / 1,\n pop / 1.\n...\nend stack.\n\nA public method is one which can handle both local messages and remote messages emanating from outside the class in which it is defined, whereas a private method can only handle local messages originating from within the class itself.\n\nProcedural Definitions\n\nA method is defined in exactly the same way as a Prolog procedure, as a collection of clauses. Each clause takes the general form :-\n\n\"Method\" :- \"Prolog++ Formulae\".\n\nwhere the body can optionally be omitted, in which case it takes the form :-\n\n\"Method\".\n\nclass stack.\n...\n\npush( Element ) :-\n contents := [Element | self::contents],\n size +== 1.\n\nprint :-\n write( self = contents ),\n nl.\n\nend stack.\nA method without any parameters takes the form :-\n\n“Name of Method”\n\nand a method which has $N$ parameters takes the form :-\n\n“Name of Method”(“Parameter₁”, …, “Parameterₙ”)\n\n**Remote Message Passing**\n\nThe fundamental communication between objects is by sending messages to one another. This takes the general form :-\n\n“Receiver” <- “Message”\n\nwhere the message receiver is either explicitly named or implicitly referred to by instance/class variables such as `self`, `sub_class`, etc..\n\n```prolog\nclass bank.\n...\n\nsimulation :-\n...\n while clock <- still_open\n do ( \n clock <- tick,\n ...\n ),\n ...\nend bank.\n```\n\n**Local Message Passing**\n\nWhen sending messages locally (i.e. to the class-instance in which they textually appear), an abbreviated form can be given :-\n\n“Message”\n\nclass teller.\n\ncreate_communal( [], _, _ ).\n\ncreate_communal( [(MeanServiceTime,ServiceVariation)|ServiceTimes], Number, Queue ) :-\n ...\n create_communal( ServiceTimes, +Number+1, Queue ).\n...\nend teller.\nMessage Broadcasting\n\nThe concept of polymorphism in OOPS means that the same method can be re-defined in several different classes. The idea is that the operation is basically the same (hence the use of the same name), but will be implemented differently according to the desired behaviour of each instance.\n\nThe polymorphism of Prolog++ allows the same message to be sent to many different objects. This is done either implicitly through the use of the plural terms like \"all instance teller\" or explicitly by the conjunction operator \",\".\n\n\\[(\\text{\"Object}_1\", \\ldots, \\text{\"Object}_k\") \\leftarrow \\text{\"Message\"}\\]\n\nclass bank.\n\n...\n\nsimulation :-\n ...\n while clock <- still_open\n do ( clock <- tick,\n ( customer, % Customers arrive when open\n all instance customer_queue, % Update queue statistics\n all instance teller % Customers served when open\n ) <- after_tick\n ),\n ... .\nend bank.\n\nIn addition to sending the same message to different objects, Prolog++ allows multiple messages to be sent to the same class/instance. This broadcasting takes the form :-\n\n\\[\\text{\"Receiver\" } \\leftarrow (\\text{\"Message}_1\", \\ldots, \\text{\"Message}_j\")\\]\n\nclass timetable.\n\n...\n\nsetup :-\n ...\n form <- ( create(_, [], first_year ),\n create(_, [], second_year ),\n create(_, [], third_year ),\n create(_, [], fourth_year )\n )\nFunctional Methods\n\nIn addition to defining general procedures, classes can include definitions of evaluable functions which return as values Prolog terms. They are similar to the evaluable functions of languages such as Lisp and Hope.\n\nFunctional Declarations\n\nFunctional methods, as with procedural methods, can be declared either as public or private.\n\n```prolog\nclass stack.\npublic method\n top // 0.\n top = Top :-\n size > 0,\n contents = [Top|_].\n...\nend stack.\n```\n\nAn evaluable function $F$ with arity $A$ is referred to by the notation $F//A$.\n\nFunctional Definitions\n\nThe definition of an evaluable function depends upon whether the value returned is arithmetic or non-arithmetic. The general form of an arithmetic function is :-\n\n```\n“Function” is “Arithmetic Expression”.\n```\n\nand the general form of a non-arithmetic function is :-\n\n```\n“Function” = “Term”.\n```\n\nwhere a parameterized function takes the form :-\n\n```\n“Name of Function”(“Parameter_1”,…,”Parameter_K”)\n```\n\nclass customer_queue.\n...\n\n```prolog\nclass customer_queue.\npublic method\n smallest_now // 0.\n...\nsmallest_now = @smallest_now( all instance class self ).\n\nprivate methods\n smallest_now // 1,\n smallest_now // 2.\n\nsmallest_now( [Queue|Queues] ) = @smallest_now( Queues, Queue ).\n\nsmallest_now( [], Smallest ) = Smallest.\n\nsmallest_now( [Queue|Queues], SmallestSoFar ) =\n @smallest_now( Queues, @smaller(Queue,SmallestSoFar) ).\n\npublic method\n average_size // 0.\n\naverage_size is nearest_number( cumulative_size / clock@time_now ).\n\n...\n\nend customer_queue\n\nIn addition, constraints may be placed upon the values of evaluable functions by attaching conditions. These take the form :-\n\n“Function” is “Arithmetic Expression” :- “Prolog++ Formulae”.\n\n“Function” = “Term” :- “Prolog++ Formulae”.\n\nclass customer_queue.\n\n...\n\nsmaller( Queue1, Queue2 ) = Queue1 :-\n Queue1 @ real_size < Queue2 @ real_size,\n !.\n\nsmaller( _, Queue2 ) = Queue2.\n\n...\n\nend customer_queue.\n\n**Evaluating Functions**\n\nA function is evaluated by sending the function call to the relevant class or instance. As with message passing, it can be a remote function call\n\n“Receiver” @ “Function”\n\n\nor a local function call\n\n@ “Function”\n\n**Arithmetic Functions**\n\nIn addition to evaluable functions defined within classes, there are certain arithmetic functions inherited from the underlying Prolog. These standard arithmetic functions are either binary or unary, with the normal precedences applying.\n\nFor a full description of arithmetic functions see the formal syntax of Prolog++ in the appendices.\nChapter 10 - The Prolog++ ↔ Prolog Interface\n\nThe interface between Prolog and Prolog++ is to a large degree seamless. Calls which are eventually handled by Prolog programs have the same appearance as messages. Messages sent from Prolog to a Prolog++ class or instance have the same appearance as any other procedure call.\n\nThe integration is mainly accomplished by the addition of two system-defined classes, one of which makes public the entire set of built-in procedures of the host Prolog engine together with any user-defined predicates.\n\nThe Implicit Class Hierarchy\nThe Prolog++ compiler automatically attaches two system-defined classes to the top-most layer of any class hierarchy. A class at the top-most layer is one which does not have any inherits declarations.\n\nAs a result of this, all classes will inherit the public methods defined by the prolog_plus_plus system class together with all of the built-ins and predicates which are made public by the prolog class.\n\nCalling Prolog From Prolog++\nOne of the benefits of having prolog as the top-most class in any hierarchy is that calling a Prolog built-in or user-defined predicate is exactly the same as sending a message to a class or instance.\n\nclass clock.\n\n...\n\nprint :-\n write( 'Closing time : ' ),\n write( @time_to_stop ),\n nl,\nwrite( 'Last customer served at : ' ),\nwrite( @time_now ),\nnl,\nnl.\n\n...\n\nend clock.\n\nIn the print method above each of the write/1 and nl/0 messages will be handled by Prolog built-in procedures, unless some other class higher up the hierarchy chooses to re-define them as Prolog++ methods.\n\nAlternatively, the messages can be sent explicitly to the prolog class, as in the alternative definition below.\n\nclass clock.\n\n...\n\nprint :-\nStop = @time_to_stop,\nNow = @time_now,\nprolog <-\n( write( 'Closing time : ' ),\n write( Stop ),\n nl,\n write( 'Last customer served at : ' ),\n write( Now ),\n nl,\n nl\n).\n\n...\n\nend clock.\n\nCalling Prolog++ From Prolog\n\nIn addition to the Prolog++ compiler which translates class definitions into collections of Prolog programs, there is a run-time predicate ->/2 for sending messages from Prolog to any Prolog++ class or instance.\n\n?- employee_record <- create(E),\n E <- get_city(C1),\n E <- set_city('Oxford'),\n E <- get_city(C2).\n\nE = ..., C1='London', C2='Oxford'\nIn the example above the predicate `<-/2` is called four times, firstly with the `employee_record` class name as a parameter and then with a system generated instance as a parameter.\nChapter 11 - The \"prolog_plus_plus\" Class\n\nThis chapter details all of the methods made public by the prolog_plus_plus class. Since this class is implicitly placed at the top of a class hierarchy these public methods are inherited by all classes.\n\nThe public methods of the prolog_plus_plus class are given below. Each method indicates whether the message should be sent to a class or an instance of a class. In some cases, for example compile/2, it is irrelevant where the message is sent. In other cases, for example isa_class/0 and isa_instance/0, it can be sent to either kind of object. Finally, certain messages such as create/1 can only be sent to a specific kind of object as indicated in the Self column.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Self</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>compile/2</td>\n<td></td>\n<td>Equivalent to the Prolog++ class compiler allows new classes to be incorporated at run-time.</td>\n</tr>\n<tr>\n<td>create/1</td>\n<td>class</td>\n<td>Create a new instance of the class.</td>\n</tr>\n<tr>\n<td>create/2</td>\n<td>class</td>\n<td>Create a new instance of the class with some initial attribute values.</td>\n</tr>\n<tr>\n<td>create/3</td>\n<td>class</td>\n<td>Create a new instance of the class with some initial attribute values and give it a reference name.</td>\n</tr>\n<tr>\n<td>delete/0</td>\n<td>instance</td>\n<td>Delete this instance.</td>\n</tr>\n<tr>\n<td>delete_all/0</td>\n<td>class</td>\n<td>Delete all instances of this class.</td>\n</tr>\n<tr>\n<td>dump/1</td>\n<td>class</td>\n<td>Dump all instances of this class to a file.</td>\n</tr>\n<tr>\n<td>dump/2</td>\n<td></td>\n<td>Dump all instances of the named classes to a file.</td>\n</tr>\n<tr>\n<td>duplicate/1</td>\n<td>instance</td>\n<td>Duplicate instance by creating a copy with the same attribute values.</td>\n</tr>\n<tr>\n<td>isa_class/0</td>\n<td>class/instance</td>\n<td>Test whether the object is a class.</td>\n</tr>\n<tr>\n<td>isa_instance/0</td>\n<td>class/instance</td>\n<td>Test whether the object is an instance of a class.</td>\n</tr>\n<tr>\n<td>kill/0</td>\n<td>class</td>\n<td>Remove the definition of a class.</td>\n</tr>\n<tr>\n<td>load/1</td>\n<td></td>\n<td>Load the previously saved class definitions from a file.</td>\n</tr>\n<tr>\n<td>optimize/0</td>\n<td>class</td>\n<td>Optimize a class’s implementation.</td>\n</tr>\n<tr>\n<td>public/1</td>\n<td>class</td>\n<td>Test or retrieve the name and arity of a public method for this class.</td>\n</tr>\n<tr>\n<td>reset/0</td>\n<td>class/instance</td>\n<td>Reset attributes of this class/instance back to their default values.</td>\n</tr>\n<tr>\n<td>reset/1</td>\n<td>class/instance</td>\n<td>Reset named attribute of this class/instance back to its default value.</td>\n</tr>\n<tr>\n<td>restore/1</td>\n<td></td>\n<td>Restore the previously saved class instances from a file.</td>\n</tr>\n<tr>\n<td>save/1</td>\n<td>class</td>\n<td>Save this class’s definition to a file.</td>\n</tr>\n<tr>\n<td>save/2</td>\n<td></td>\n<td>Save the definitions of the named classes to a file.</td>\n</tr>\n</tbody>\n</table>\n**when_error/2 class/instance** A catchall method for handling errors which were raised by the system but not handled by the erroneous class.\n**compile/2**\n\n*the run-time compiler for incorporating new classes*\n\n**Syntax**\n\n\\[\n\\text{compile}( \\text{Class}, \\text{Sentences} ) \\\\\n+\\text{Class} \\quad \\langle \\text{atom} \\rangle \\\\\n+\\text{Sentences} \\quad \\langle \\text{list of class declarations and definitions} \\rangle\n\\]\n\n**Comments**\nThe `compile/2` predicate invokes the Prolog++ compiler so that new classes can be incorporated at run-time. It does not matter which class the message is sent, although for clarity it makes sense to send the message to the \"prolog_plus_plus\" class itself.\n\n**Exceptions**\nThe errors raised by this method are those detailed in appendix E for the Prolog++ compiler.\n\n**Example**\nThe following example creates a new \"stack\" class with the given categories, inheritance and public methods.\n\n\\[\n?\\text{- prolog_plus_plus} \\leftarrow \\text{compile(} \\\\\n\\quad \\text{stack,} \\\\\n\\quad [ \\\\\n\\quad \\text{( categories} \\\\\n\\quad \\quad \\text{library ,} \\\\\n\\quad \\quad \\text{buffer } ), \\\\\n\\quad \\text{( inherit} \\\\\n\\quad \\quad \\text{buffer },) \\quad \\text{\\%A stack is a kind of buffer.} \\\\\n\\quad \\text{( public methods} \\\\\n\\quad \\quad \\text{nil // 0 ,) \\quad \\text{\\%A nil stack} \\\\\n\\quad \\quad \\text{push // 2 ,) \\quad \\text{\\%Push something onto the stack} \\\\\n\\quad \\quad \\text{pop // 2 ,) \\quad \\text{\\%Pop something off the stack} \\\\\n\\quad \\quad \\text{top // 1 ,) \\quad \\text{\\%Return the top of the stack} \\\\\n\\quad \\quad \\text{list // 1),) \\quad \\text{\\%Return contents of the stack} \\\\\n\\quad \\quad \\text{( nil = [ ] ,) \\\\\n\\quad \\quad \\text{ ( push( Item, Stack ) = [Item|Stack] ) ,} \\\\\n\\quad \\quad \\text{ ( pop( Item, [Item|Stack] ) = Stack ) ,} \\\\\n\\quad \\quad \\text{ ( top( [Item|_] ) = Item ),} \\\\\n\\quad \\quad \\text{ ( list( Stack ) = Stack )} \\\\\n\\quad ]).}\n\\]\n\n**create/1**\n\n*create a new instance of a class*\n\n**Syntax**\n\n\\[\n\\text{create}( \\text{Instance} ) \\\\\n-\\text{Instance} \\quad \\langle \\text{variable} \\rangle\n\\]\n\n**Comments**\nCreate a new instance of the class which received the message, returning the unique handle for that instance.\n\n**Exceptions**\n- The message is sent to an existing instance rather than a class.\n- `Instance` is already instantiated when the message is sent.\nExample\n\nThe following example creates a new instance of the class \"unicycle\" and returns its handle.\n\n?- unicycle <- create(C).\nCreated: wheel|198130\nCreated: rim|198132\nCreated: spoke|198134\nCreated: spoke|198136\nCreated: spoke|198138\nCreated: frame|198140\nCreated: seat|198142\nC = (unicycle|198129)\n\ncreate/2\ncreate a new instance of a class with a collection of attribute values\n\nSyntax\ncreate( Instance, AttributeValues )\n-Instance <variable>\n+AttributeValues <(attribute is value) or (attribute = value) list>\n\nComments Create a new instance of the class which received the message, returning the unique handle for that instance. In addition, assign the designated attributes to their corresponding arithmetic (is) or non-arithmetic (=) values.\n\nExceptions\n- The message is sent to an existing instance rather than a class.\n- Instance is already instantiated when the message is sent.\n- The attribute-value pairs are not of the expected form.\n\nExample\n\nThe following example creates an instance of the \"stack\" class with the given \"contents\" and \"size\" attribute values and returns its handle.\n\n?- stack <- create(S,[contents=[a],size is 1]).\nS = (stack|201322)\n\ncreate/3\ncreate a new instance of a class with a collection of attribute values and assign to it a mnemonic handle by which it can be referred\n\nSyntax\ncreate( Instance, AttributeValues, Mnemonic )\n-Instance <variable>\n+AttributeValues <(attribute is value) or (attribute = value) list>\n+Mnemonic <non-variable>\n\nComments Create a new instance of the class which received the message, returning the unique handle for that instance. In addition, assign the designated attributes to their corresponding arithmetic (is) or non-arithmetic (=) values and record the\nassociation between the instance’s handle and its mnemonic name for future reference.\n\nExceptions\n\n- The message is sent to an existing instance rather than a class.\n- *Instance* is already instantiated when the message is sent.\n- The attribute-value pairs are not of the expected form.\n- *Mnemonic* is not instantiated when the message is sent.\n- *Mnemonic* unifies with the mnemonic name of an existing instance.\n\nExample\n\nThe following example creates an instance of the \"stack\" class with the given \"contents\" and \"size\" attribute values. It also sets a mnemonic \"stack1\" for the instance and returns its handle.\n\n?- stack <- create(S,[contents=[a],size is 1],stack1). \nS = (stack|201322)\n\n---\n\ndelete/0\n\ndelete this instance\n\nComments\n\nDelete the class instance to which the message was sent. In addition, if this is the composite part of a complex object then all of its component parts will also be deleted.\n\nExceptions\n\n- The message is sent to a class rather than an instance of a class.\n- The instance to be deleted is a component of some complex object.\n\nExample\n\nThe following example creates and then deletes an instance of the \"unicycle\" class.\n\n?- unicycle <- create(C), C <- delete. \nC = (unicycle|243187)\n\n---\n\ndelete_all/0\n\ndelete all class instances\n\nComments\n\nDelete all instances of the class to which the message was sent. In addition, if any of those are the composite part of a complex object then all of their corresponding component parts will also be deleted.\n\nExceptions\n\n- The message is sent to an instance rather than a class.\n- One or more of the class instances is a component of some other complex object.\nExample\n\nThe following example creates two instances for the \"unicycle\" class and then deletes them.\n\n?- unicycle <- create(C1),\n unicycle <- create(C2),\n unicycle <- delete_all.\nC1 = (unicycle|249426)\nC2 = (unicycle|249451)\n\ndump/1\n\ndump all class instances into a file\n\nSyntax\ndump( File )\n\n+File <prolog_file_specification>\n\nComments\nDump all the instances of the class to which the message is sent. This involves storing their attribute values and part-of structures in the specified file.\n\nExceptions\n- The message is sent to an instance rather than a class.\n- File is not a Prolog file specification.\n- One or more attributes of the instances reference some other instance which is not being dumped to the same file. That is, no dangling references are allowed.\n- One or more of the instances is a component in a complex object which by definition is itself not being dumped to the same file. Again, no dangling references are allowed.\n\nExample\n\nThe following example dumps all the instances of the \"unicycle\" class into the file \"UNICYCLE.PC\"\n\n?- unicycle <- dump( 'unicycle' ).\n\ndump/2\n\ndump all class instances of the specified classes into a file\n\nSyntax\ndump( File, Classes )\n\n+File <prolog_file_specification>\n+Classes <list of atom>\n\nComments\nDump all the instances of the specified classes into the file. This involves storing their attribute values and part-of structures.\n\nExceptions\n- File is not a Prolog file specification.\n- Classes is not a list of atoms.\n• One or more attributes of the instances reference some other instance which is not being dumped to the same file. That is, no dangling references are allowed.\n\n• One or more of the instances is a component in a complex object which is itself not being dumped to the same file. Again, no dangling references are allowed.\n\n**Example** \nThe following example dumps all the instances of the class \"cycle\" to the file CYCLES.PC.\n\n?- prolog_plus_plus <- dump('Cycles', (category cycle)).\n\n---\n\n**duplicate/1**\n\n`duplicate this instance`\n\n**Syntax**\n\nduplicate( Instance )\n\n- `Instance` <variable>\n\n**Comments**\n\nDuplicate the instance to which the message is sent. This involves creating a new instance of the same class and then copying all of the original’s attribute values. In addition, if the original instance has any component parts they too are duplicated and the part-of structure itself is copied.\n\n**Exceptions**\n\n• The message is sent to a class rather than an instance of a class.\n\n• `Instance` is already instantiated when the message is sent.\n\n**Example**\n\nThe following example creates an instance of the \"stack\" class, then creates a duplicate of that instance and finally tests the \"contents\" attribute of the duplicate instance to see if it is identical to the original instance.\n\n?- stack <- create(S1, [contents=[a], size is 1]),\n S1 <- duplicate(S2),\n S2 <- @contents = C.\n\nS1 = (stack|263188)\nS2 = (stack|263201)\nC = [a]\n\n---\n\n**isa_class/0**\n\n`has this message been sent to a class?`\n\n**Comments**\n\nThe message is successful when sent to a class but not when sent to an instance of a class.\n\n**Example**\n\nThe following example tests whether the class \"stack\" is indeed a class.\n\n?- stack <- isa_class.\n yes\nThe next example creates an instance of the \"stack\" class and then confirms that this is not a class.\n\n?- stack <- create(S), S <- isa_class.\nno\n\n**isa_instance/0**\n\n*has this message been sent to an instance of a class?*\n\n**Comments**\nThe message is successful when sent to an instance of a class but not when sent to a class itself.\n\n**Example**\nThe following example confirms that the class \"stack\" is not an instance.\n\n?- stack <- isa_instance.\nno\n\nThe next example creates an instance of the \"stack\" class and then confirms that this is indeed an instance.\n\n?- stack <- create(S), S <- isa_instance.\nyes\n\n**kill/0**\n\n*remove the class definition and all instances*\n\n**Comments**\nRemove the class to which the message is sent. Furthermore, remove all instances of that class together with their component parts.\n\n**Exception**\n- The message is sent to an instance rather than a class.\n\n**Example**\nThe following example removes the \"unicycle\" class and all its instances.\n\n?- unicycle <- kill.\n\n**load/1**\n\n*load the class definitions from file*\n\n**Syntax**\nload( File )\n\n+File <prolog_file_specification>\n\n**Comments**\nLoad the class definitions which had previously been saved to the specified file.\n\n**Exception**\n- *File* is not a Prolog file specification.\n\n**Example**\nThe following example loads all the class definitions in the file \"CYCLES.PC\".\n\n?- prolog_plus_plus <- load( 'CYCLES' ).\noptimize/0\n\noptimize the class\n\nComments\nOptimize the previously compiled class to which the message is sent.\n\nException\n• The message is sent to an instance rather than a class.\n\nExample\nThe following example optimizes the definition of the \"stack\" class.\n?- stack <- optimize.\n\npublic/1\n\nthe method is public\n\nSyntax\npublic( Method )\n\n?Method <atom> / <integer>\n\nComments\nMethod is instantiated or unified with the structure MethodName / MethodArity where these are publicly declared methods of the class to which the message is sent.\n\nException\n• The message is sent to an instance rather than a class.\n\nExample\nThe following example returns the public methods of the \"stack\" class.\n?- stack <- public( M ).\n\nM = push / 1 ;\nM = pop / 1 ;\nM = top / 1 ;\nM = empty / 0\n\nreset/0\nreset attribute values\n\nComments\nReset the attributes back to their default values. If the message is sent to a class then the class attributes are reset, whereas if the message is sent to an instance then the instance attributes are reset.\n\nExample\nThe following example resets the class attributes of the \"customer_queue\".\n?- customer_queue <- reset.\n\nThe next example resets the instance attributes of all the instances of the class \"customer_queue\".\n?- all instances customer_queue <- reset.\nreset/1\nreset an attribute value\n\nSyntax\n reset( Attribute )\n+Attribute <atom>\n\nComments\n Reset the specified attribute back to its default value.\n\nExample\n The following example\n\n?- customer_queue <- reset( smallest_now ).\n?- all instances customer_queue <- reset( my_neighbour ).\n\nrestore/1\nload the instances from file\n\nSyntax\n restore( File )\n+File <prolog_file_specification>\n\nComments\n Load the instances which had previously been dumped to the specified file. In addition, restore all of their attribute values and part-of hierarchies.\n\nException\n • File is not a Prolog file specification.\n\nExample\n The following example loads the instances from the CYCLES.PC file.\n\n?- prolog_plus_plus <- restore( 'Cycles' ).\n\nsave/1\nsave the class definition to a file\n\nSyntax\n save( File )\n+File <prolog_file_specification>\n\nComments\n Save in the specified file the class to which the message is sent.\n\nExceptions\n • The message is sent to an instance rather than a class.\n • File is not a Prolog file specification.\n\nExample\n The following example saves the class definition of the unicycle class in the file UNICYCLE.PC\n\n?- unicycle <- save( 'UNICYCLE' ).\nsave/2\n\nsave all classes into the file\n\nSyntax\nsave( File, Classes )\n+File <prolog_file_specification>\n+Classes <list of atom>\n\nComments\nSave the definitions of all the specified classes into the file.\n\nExceptions\n• File is not a Prolog file specification.\n• Classes is not a list of atoms.\n\nExample\nThe following example saves all the currently defined classes in the cycle category in the file CYCLES.PC.\n\n?- prolog_plus_plus <- save( 'CYCLES', (category cycle) ).\n\nwhen_error/2\n\nreact to an exception in the standard Prolog++ manner\n\nSyntax\nwhen_error( Exception, Message )\n+Exception <any term>\n+Message <prolog++ message>\n\nComments\nReact to the specified Exception, which was raised by sending the Message to the recipient object, in the standard Prolog++ manner.\n\nExample\nThe following example reacts to the instantiation error when sending the create/1 message to the unicycle class.\n\n?- unicycle <- when_error( instantiation_error, create(fred) ).\n\nwhich is equivalent to\n\n?- unicycle <- create(fred).\n\nproviding that the methods when_error/2 and create/1 are not made public by the class unicycle or any of its ancestors. That is, providing both messages are eventually handled by the prolog_plus_plus class.\nPart 4 - Operational Features Of Prolog++\nChapter 12 - Reacting To Class Instances\n\nWhenever a new instance of a class is created it is likely that it will need to be specialized in some way with its own set of characteristics.\n\nFor example, suppose we have implemented an object-oriented database as part of a company’s payroll system. As new employees join the company so new instances of an employee class need to be created. The details of the employee, for example name, address, NI number, etc., must be collected and added as attributes of the new instance. To cater for this situation, a when_created/0 method can be defined which reacts to the creation of new instances.\n\nSimilarly, an employee leaving the company may require certain modifications to the database other than the simple deletion of their associated instance. This tidying up process can be implemented by a when_deleted/0 method.\n\nWhen A New Instance Is Created\nThe when_created/0 method reacts whenever a new instance of a class is created. The message is sent by Prolog++ immediately after it has created the new instance.\n\nFor example, a method which reacts to new employees joining the company might automatically assign that employee the next payroll number in sequence.\n\nclass employee.\n\npublic instance attribute payroll_number.\nwhen_created :-\n payroll_number := @next_payroll_number.\n\nprivate class attribute last_payroll_number is 100000.\nprivate method next_payroll_number//0.\nnext_payroll_number is @last_payroll_number :-\n last_payroll_number += 1.\nend employee.\n\nThe creation of an instance is implemented as if by the prolog_plus_plus method.\n\ncreate( Instance ) :-\n prolog <- create_class_instance( self, Instance ),\n while Instance <- when_created\n do true.\nWhen An Existing Instance Is Deleted\n\nThe `when_deleted/0` method reacts whenever an existing instance of a class is deleted. The message is sent by Prolog++ immediately before it is removed.\n\nFor example, a method which reacts to old employees leaving the company might automatically issue the appropriate social security notice.\n\nclass employee.\n\nwhen_deleted :-\n self <- issue_p45_form.\nend employee.\n\nThe deletion of an instance is implemented as if by the `prolog_plus_plus` method.\n\ndelete :-\n while self <- when_deleted do true,\n prolog <- delete_class_instance( self ).\nChapter 13 - Reacting To Attribute Values\n\nMost procedural languages such as C, Fortran and Pascal, and most OOPS such as C++ and Smalltalk, are typed languages. That is, everything is known at compile-time about the possible values which variables, functions, attributes etc. can take. However, since Prolog++ is fundamentally based upon the typeless language Prolog it has no built-in type checking. This is both a positive and a negative feature of the language. It is positive in the sense that not having to make type declarations has been shown to improve the productivity of Prolog (and thus Prolog++) programmers. It is negative in the sense that type declarations allow the compiler to make certain assumptions about the program, and so improve its run-time efficiency. More important, though, type declarations pick up programming errors at compile time and also invalid data at run-time.\n\nIn Prolog++ methods can be defined which determine the (in)validity of attribute values. Moreover, such methods need not be restricted to simple type checking along the lines of traditional languages, but may involve comparisons between the incoming data and any existing data. This general constraint mechanism is far more powerful than any static type checking system.\n\nIn addition to checking the value of an attribute before it is assigned, methods can be defined which react to assignments after they have been made. For example, the classic rule of stock control management which states that a re-order must be made whenever the stock level of an item falls below some critical level can easily be implemented by one of these methods.\n\n```prolog\npublic instance attributes\n stock_level is 0,\n re_order_level.\n\nwhen_assigned( stock_level, _ ) :-\n Level < re_order_level,\n self <- issue_re_order.\n```\n\nInvalid Attribute Values\n\nThe general form for this method is\n\n```\ninvalid( AttributeName, NewValue )\n```\n\nand is invoked immediately before the NewValue is assigned to the AttributeName. The message is sent by Prolog++ to the object (class or instance) whose attribute is about to be updated.\n\nFor example, all employee NI numbers must follow a fixed format.\n\n```\ninvalid( ni_number, NI ) :-\n ^ ni_number_format( NI ).\n```\n\nProlog++ Reference\nThe update of an attribute value is partially implemented as if by the `prolog_plus_plus` method.\n\n```\nAttributeName := NewValue :-\n self <- invalid( AttributeName, NewValue ),\n \\!,\n self <- when_error( invalid, (AttributeName := NewValue) ).\n```\n\n```\nAttributeName := NewValue :-\n prolog <- update_attribute_value(self,AttributeName,NewValue).\n```\n\n### Reacting To New Attribute Values\n\nThe general form for this method is\n\n```\nwhen_assigned( AttributeName, OldValue )\n```\n\nand is invoked immediately after the `OldValue` for the `AttributeName` has been replaced. Thus, the new value is available by inspection of the attribute.\n\nFor example, a simple log of attribute updates can be encoded by the following method.\n\n```\nwhen_assigned( AttributeName, OldValue ) :-\n NewValue = @AttributeName,\n write( self ),\n write( ' @ ' ),\n write( AttributeName ),\n write( ' updated from ' ),\n write( OldValue ),\n write( ' to ' ),\n write( NewValue ),\n nl.\n```\n\nThe update of an attribute value is implemented as if by the `prolog_plus_plus` method.\n\n```\nAttributeName := NewValue :-\n self <- invalid( AttributeName, NewValue ),\n \\!,\n self <- when_error( invalid, (AttributeName := NewValue) ).\n```\n\n```\nAttributeName := NewValue :-\n OldValue = @AttributeName,\n prolog <- update_attribute_value(self,AttributeName,NewValue),\n while self <- when_assigned( AttributeName, OldValue )\n do true.\n```\nChapter 14 - Exception Handling\n\nMany programming errors and invalid data items can be trapped by Prolog++. \n\nFor example, sending an unrecognised message to an object (class or instance) will result in that message eventually reaching the prolog_plus_plus class. If at this point the message is still not recognised and furthermore it cannot be handled by a Prolog predicate, then a no_message_handler exception will be raised.\n\nExceptions are raised in Prolog++ by sending an exception message back to the object which received the original message.\n\nFor example, suppose the instance (teller|123456) is sent the unrecognised message you_cannot_handle_me. The system will respond by sending the message\n\n```\nwhen_error( \n no_message_handler,\n you_cannot_handle_me\n);\n```\n\nback to instance (teller|123456). If this exception message is not handled by the class hierarchy it will eventually find its way back to the prolog_plus_plus class for handling in the standard Prolog++ way.\n\nclass complex.\n public instance attribute valp.\n setp(Rho,Theta) :-\n valp &= polar(Rho,Theta).\n getp(Rho,Theta) :-\n @valp = polar(Rho,Theta).\n invalid(Attribute,Value) :-\n \n valid(valp,polar(Rho,Theta)) :-\n number(Rho),\n number(Theta).\n when_error( no_message_handler, _ ) :-\n !, \n fail.\n when_error( Exception, Message ) :-\n super <- when_error( Exception, Message ).\nend complex.\n\nclass sub_complex.\n inherit complex.\n when_error( invalid, _ ) :-\n !.\n when_error( Exception, Message ) :-\n\nsuper <- when_error( Exception, Message ).\nend sub_complex.\n\nNote the manner in which when_error/2 messages are passed up the hierarchy by re-\nsending those not handled locally up to super.\n\nThe classes sub_complex and complex only differ in the way invalid exceptions are handled.\n\n?- complex <- create(C),\n C <- setp(1,two),\n C <- getp(R,T).\n* Prolog++ Run-Time Error\n* (complex|437089)<-valp=polar(1, two)\n\n?- sub_complex <- create(C),\n C <- setp(1,two),\n C <- getp(R,T).\nC = (sub_complex|437664),\nR = 1,\nT = two\n\n?- complex <- can_you_handle_me.\nno\n\n?- sub_complex <- can_you_handle_me.\nno\n\n?- complex <- create(me).\n* Prolog++ Run-Time Error\n* complex<-create(me)\n\n?- sub_complex <- create(me).\n* Prolog++ Run-Time Error\n* sub_complex<-create(me)\nPart 5\n\nAppendices\nAppendix A - Formal Syntax Of Prolog++\n\nThis appendix details the formal syntax of Prolog++ programs. It is the definitive specification of all constructs which can appear within a Prolog++ instance.\n\nHow To Read The Grammar Rules\nThe formal syntax of Prolog++ is defined in the following sections by grammar rules having the general form :-\n\n```\nnon_terminal → phrase₁,₁ phrase₁,₂ ... phrase₁,k₁\nor phrase₂,₁ phrase₂,₂ ... phrase₂,k₂\nor ...\nor phraseₙ,₁ phraseₙ,₂ ... phraseₙ,kₙ\n```\n\nwhere n ≥ 1 represents the number of different definitions for the non_terminal and km ≥ 1 (for every 1 ≤ m ≤ n) represents the number of phrases in each definition. Each phraseᵢ,j is either itself a grammatical construct or a terminal symbol. To assist the reading of these rules all terminal symbols in the text are in **bold** type.\n\nA few basic grammar rules are presented below which will be used in the more complex grammar rules of the following sections.\n\nThe name of something is a Prolog atom (other than []).\n\n```\nname.<type> → prolog_atom\n```\n\nMeta phrases of a particular type are given by Prolog variables, but they must be instantiated to something of that type at run-time.\n\n```\nmeta.<type> → prolog_variable\n```\n\nTerms of a particular type can be specified by any legal Prolog++ term, but they must evaluate to something of that type at run-time.\n\n```\nterm.<type> → term\n```\n\nAn arity is a Prolog integer greater than or equal to zero which represents the number of arguments for the associated method.\nA parameter is any Prolog term which appears in the head (left-hand side) of a definition.\n\nSequences are grammatical constructs separated by commas.\n\nClass\nA class definition is a sequence of sentences delimited by begin and end statements. Both the begin and end statements must name the class being defined.\n\nEach individual sentence represents either a declaration or a definition, and is always terminated with a period (.)\n\nDeclarations\nA declaration states how classes are related to each other (through categories, inheritance links or component links), the attributes of the class and the methods used to handle messages.\nCategories Declaration\n\nCategories are used to cluster classes so that communal operations (such as kill, save, etc.) can be applied without prior knowledge of which classes form the category. A class which does not declare any categories is assumed to be in the user category.\n\nFor example, when Prolog++ clears its workspace all classes in the user category are killed but none of the system or library classes are killed.\n\ncategory_declaration\n→ categories sequence.name.category\n\nInherits Declaration\n\nClasses can be is-a related to form inheritance hierarchies. Attributes and methods which are not defined locally are inherited according to such declarations.\n\ninherits_declaration\n→ inherits sequence.name.super_class\n\nSuper classes are generalisations of more specific classes.\n\nWhen more than one super-class is declared the hierarchy in which it exists is said to exhibit multiple inheritance. In such cases the ordering of super-classes in the declaration is very important as this determines the order of search for inherited attributes and methods.\n\nParts Declaration\n\nClasses can be part-of related to form component hierarchies.\n\nparts_declaration\n→ parts sequence.part_specification\n\npart_specification\n→ name.class • partEnumeration\nor name.class\n\npartEnumeration\n→ term\nA part-of hierarchy determines how instances of that class are created. If no parts exist then only an instance of the class is created. If parts do exist then instances of the part classes are created in addition to an instance of the class itself. Similarly, when instances of a class are deleted all of its component parts are also deleted.\n\nFor example, whenever a specific bicycle is created, a pair of handle-bars, a frame, a seat and two wheels (each consisting of a rim and 12 spokes) might also created with the appropriate links established between those component instances and the bicycle instance.\n\nParts can be inherited from super-classes. Note that only the part names which are not declared locally will be inherited.\n\nFor example, a tandem might have two pairs of handle-bars and two seats in addition to the frame and two wheels inherited from a normal bicycle.\n\n**Attributes Declaration**\n\nAttribute declarations determine the dynamic characteristics of a class and its instances. They are sometimes referred to as class-instance/object variables in other OO languages. The terminology chosen here is simply to avoid confusion with the notion of a Prolog variable.\n\nThe attributes of a class are not only those explicitly declared but also those of any of its super-classes, super-super-classes, etc.. That is, the total set of attributes for a class is the union of its locally declared attributes and those of all its ancestor classes.\n\nThere are two distinct types of attributes, those assigned to instances of the class and those assigned to the class itself. For example, an individual instance of a queue may have an attribute called size and the queue class itself may have an attribute called smallest which points to that particular instance which has the smallest size value.\n\nClass attributes are prefixed with the keyword `class` and instance attributes are prefixed with the keyword `instance`.\n\nAttributes can be declared `public` or `private`. Public attributes can be accessed from outside the class in which they are textually declared, whereas private attributes can only be accessed from within. In both cases, however, the assignment of new values must be done locally.\n\n```\nattributes_declaration → attribute_mode\n attribute_type\n attributes\n sequence.attribute_default\n\nattribute_mode\n → private\n or public\n```\n\n**Prolog++ Reference**\nAn attribute can be given a default value when it is declared. If it is not then any attempted accesses will fail until the attribute is assigned a current value.\n\nThe default value can be an arithmetic expression (using `is`) which is automatically evaluated by the Prolog built-in `is/2`, a non-arithmetic term (using `=`) or its default can be inherited from some ancestor class in which that same attribute is declared.\n\nNote that a default value of the form\n\n```\nname.attribute is term\n```\n\nis equivalent to\n\n```\nname.attribute = +( term )\n```\n\nMethods Declaration\n\nA methods declaration states what kind of messages can be handled by a class. Any other message will be passed up the is-a hierarchy to one of its ancestor classes which is capable of handling it.\n\nMethods can be declared public or private. Public methods can handle messages originating from outside the class in which they are textually declared as well as from inside, whereas private methods can only handle messages originating from within.\n\n```\nmethod_declaration\n → method_mode methods\n sequence.method_arity\n\nmethod_mode\n → public\n or private\n```\n\nMethod declarations are classified as procedural (using `/`) or as functional (using `//`).\nDefinitions\nDefinitions can be given for functional or procedural methods. In either case the definiens can be qualified by a series of statements or not, thus taking the same general form as Prolog clauses.\n\n```\ndefinition\n ➔ definiens :- statements\n or definiens\n\ndefiniens\n ➔ functional_definiens\n or procedural_definiens\n```\n\nFunctional Method Definition\nA functional definition specifies the head of a method for handling functional messages. The value of a function can either be arithmetic (using `is`) which is evaluated by the Prolog built-in `is/2`, or non-arithmetic (using `=`).\n\n```\nfunctional_definiens\n ➔ functional_head is term\n or functional_head = term\n```\n\nNote that a functional definition of the form\n\n```\nfunctional_head is term\n```\n\nis equivalent to\n\n```\nfunctional_head = +( term )\n```\n\nThe head of a functional method is similar to the head of a Prolog clause.\n\n```\nfunctional_head\n ➔ name.method(sequence.parameter) {arity > 0}\n or name.method {arity = 0}\n```\n\nProcedural Method Definition\nA procedural definition specifies a method for handling procedural messages.\n\nCertain special procedures, namely error handlers, constraint handlers, attribute assignments and the creation or deletion of class instances are recognised as having special significance in Prolog++. \n\nProlog++ Reference\nprocedural_definiens\n\n→ message_handler_definiens\nor error_handler_definiens\nor constraint_handler_definiens\nor assignment_handler_definiens\nor create_handler_definiens\nor delete_handler_definiens\n\nIn all cases, the definiens of a procedural method is like the head of a Prolog clause. The parameters are treated in exactly the same manner as the parameters in the head of a Prolog clause, unifying with the arguments passed when a message is sent.\n\n**Message Handler Definiens**\n\nA general message handler either has many parameters (arity>0) or no parameters (arity=0).\n\n`message_handler_definiens` → `name.method( sequence.parameter )` {arity > 0}\n\nor `name.method` {arity = 0}\n\n**Error Handler Definiens**\n\nAn error handler is defined in exactly the same manner as general procedural methods. They can be handled locally, inherited or even passed progressively up the class hierarchy through the `super` variable.\n\nError handlers are given special significance because the underlying Prolog++ engine may raise errors which the programmer then has the capability of trapping.\n\n`error_handler_definiens` → `when_error( parameter.term.error , parameter.message )`\n\nThe error (1st parameter) is a Prolog term indicating the type of error, such as instantiation faults, domain violations, etc.. A `when_error/2` message is sent to the same `self` variable to which the original erroneous message (2nd parameter) was sent.\n\nThe error controller is implemented as if it were a Prolog++ method of the form :-\n\n```\nerror_controller( Exception, Message ) :-\n self <- when_error( Exception, Message ).\n```\n\n```\nwhen_error( Exception, Message ) :-\n prolog <- run_time_error_dialog( Exception, Message, self ).\n```\nConstraint Handler Definiens\n\nA constraint governs the assignment of attribute values. The assignment is not permitted if any of the invalidity constraints governing that particular attribute hold, and is permitted otherwise. In addition, whenever an invalidity constraint is violated an appropriate error is raised.\n\n\\[\n\\text{constraint\\_handler\\_definiens} \\\\\n\\quad \\rightarrow \\quad \\text{Invalid( parameter\\_name\\_attribute, parameter\\_value )}\n\\]\n\nThe constraint checker is implemented as if it were a Prolog++ method of the form :-\n\n\\[\n\\text{constraint\\_checker( Attribute, NewValue ) :-} \\\\\n\\quad \\text{self <- invalid( Attribute, NewValue ),} \\\\\n\\quad \\text{!,} \\\\\n\\quad \\text{self <- when\\_error( invalid, (Attribute := NewValue) ).}\n\\]\n\n\\[\n\\text{constraint\\_checker( _, _ ).}\n\\]\n\nAssignment Handler Definiens\n\nAn assignment handler reacts after the assignment of an attribute.\n\n\\[\n\\text{assignment\\_handler\\_definiens} \\\\\n\\quad \\rightarrow \\quad \\text{when\\_assigned(}\n\\quad \\quad \\text{parameter\\_name\\_attribute,}\n\\quad \\quad \\text{parameter\\_oldvalue}\n\\quad \\text{)}\n\\]\n\nWhenever an attribute is assigned a new value all of the handlers governing that attribute are invoked. The assignment controller is implemented as if it were a Prolog++ method of the form :-\n\n\\[\n\\text{assignment\\_controller( Attribute, OldValue ) :-} \\\\\n\\quad \\text{self <- when\\_assigned( Attribute, OldValue ),} \\\\\n\\quad \\text{fail.}\n\\]\n\n\\[\n\\text{assignment\\_controller( _, _ ).}\n\\]\n\nCreate Handler Definiens\n\nA create procedure reacts to the creation of a new class instance. It is invoked immediately after the actual instance is created.\n\n\\[\n\\text{create\\_handler\\_definiens} \\\\\n\\quad \\rightarrow \\quad \\text{when\\_created}\n\\]\n\nWhenever an instance is created all of the handlers are invoked. The creation controller is implemented as if it were a Prolog++ method of the form :-\ncreation_controller :-\n self <- when_created,\n fail.\n\ncreation_controller.\n\nDelete Handler Definiens\n\nA delete procedure reacts to the deletion of an existing class instance. It is invoked immediately before the actual instance is deleted.\n\n\\[\n\\text{delete_handler_definiens} \\\\\n\\rightarrow \\text{when_deleted}\n\\]\n\nWhenever an instance is deleted all of the handlers are invoked. The deletion controller is implemented as if it were a Prolog++ method of the form :-\n\ndeletion_controller :-\n self <- when_deleted,\n fail.\ndeletion_controller.\n\nProlog++ Statements\n\nProlog++ statements are made up of conjunctions, disjunctions, negations, universals, existentials, sets, etc..\n\n\\[\n\\text{statements} \\\\\n\\rightarrow \\text{meta.statements} \\\\\n\\text{or \\quad \\text{statements}} \\quad , \\quad \\text{statements} \\\\\n\\text{or \\quad statements} \\quad ; \\quad \\text{statements} \\\\\n\\text{or \\quad statements} \\quad -\\rightarrow \\quad \\text{statements} \\\\\n\\text{or \\quad forall \\quad statement \\quad \\text{do} \\quad \\text{statement}} \\\\\n\\text{or \\quad while \\quad statement \\quad \\text{do} \\quad \\text{statement}} \\\\\n\\text{or \\quad repeat \\quad statement \\quad \\text{until} \\quad \\text{statement}} \\\\\n\\text{or \\quad \\text{not} \\quad \\text{statement}} \\\\\n\\text{or \\quad solution_collector(} \\\\\n\\text{\\quad prolog_term,} \\\\\n\\text{\\quad statement,} \\\\\n\\text{\\quad prolog_variable) } \\\\\n\\text{\\quad )} \\\\\n\\text{or \\quad prolog_term} \\quad ^\\text{\\quad statement} \\\\\n\\text{or \\quad statement}\n\\]\nAn individual statement is either a simple Prolog control structure, an assignment of some value to an attribute or the sending of a message. An individual statement can also be some compound statements delimited by round brackets.\n\n```\nsolution_collector\n → setof\n or bagof\n or findall\n```\n\nControl\n\nSimple control statements such as `!`, `true`, `fail` and `repeat` are treated exactly the same as they are in Prolog clauses.\n\n```\ncontrol\n → !\n or true\n or fail\n or repeat\n```\n\nAttribute Assignment\n\nThe left-hand side of an assignment statement refers to the name of the attribute which is being assigned and the right-hand side is the value which it is given.\n\nThe class (if it is a class attribute) or the instance (if it is an instance attribute) which is assigned the new attribute value is determined by the `self` variable.\n\nIf the value assigned is an arithmetic expression it will be evaluated using the Prolog built-in predicate `is/2`.\n\n```\nattribute_assignment\n → name.attribute assign_operator term\n```\n\nThe type of assignment operator determines whether or not constraint checking and assignment handlers will be invoked. These are referred to, respectively, as noisy assignments and quiet assignments.\n\n```\nassign_operator\n → noisy_assign_operator\n or quiet_assign_operator\n```\nNoisy Assignment Operators\n\nA noisy assignment will invoke any associated constraint checking and/or assignment handlers. The first assignment operator applies to all symbolic values whereas the others only apply to arithmetic values.\n\n\\[\n\\text{noisy\\_assign\\_operator} \\\\\n\\rightarrow \\&= \\{\\text{Replace attribute with symbolic value}\\} \\\\\n\\text{or} \\ : = \\{\\text{Replace attribute with arithmetic value}\\} \\\\\n\\text{or} \\ + = \\{\\text{Add to arithmetic attribute value}\\} \\\\\n\\text{or} \\ - = \\{\\text{Subtract from arithmetic attribute value}\\} \\\\\n\\text{or} \\ *= \\{\\text{Multiply arithmetic attribute value by \\ldots}\\} \\\\\n\\text{or} \\ /= \\{\\text{Divide arithmetic attribute value by \\ldots}\\}\n\\]\n\nQuiet Assignment Operators\n\nA quiet assignment in contrast to a noisy assignment will not invoke any associated constraint checking or any associated assignment handlers. The first assignment operator applies to all symbolic values whereas the others only apply to arithmetic values.\n\n\\[\n\\text{quiet\\_assign\\_operator} \\\\\n\\rightarrow \\&== \\{\\text{Replace attribute with symbolic value}\\} \\\\\n\\text{or} \\ : == \\{\\text{Replace attribute with arithmetic value}\\} \\\\\n\\text{or} \\ + == \\{\\text{Add to arithmetic attribute value}\\} \\\\\n\\text{or} \\ - == \\{\\text{Subtract from arithmetic attribute value}\\} \\\\\n\\text{or} \\ *= \\{\\text{Multiply arithmetic attribute value by \\ldots}\\} \\\\\n\\text{or} \\ /= \\{\\text{Divide arithmetic attribute value by \\ldots}\\}\n\\]\n\nProcedural Message Passing\n\nProcedural messages can either be sent explicitly to a remote class/instance or sent implicitly to the local self variable.\n\n\\[\n\\text{send\\_message} \\\\\n\\rightarrow \\text{send\\_remote\\_message} \\\\\n\\text{or} \\text{send\\_local\\_message}\n\\]\n\n\\[\n\\text{send\\_remote\\_message} \\\\\n\\rightarrow \\text{sequence.receiver} \\leftarrow \\text{sequence.procedural\\_message}\n\\]\n\n\\[\n\\text{send\\_local\\_message} \\\\\n\\rightarrow \\text{procedural\\_message}\n\\]\n\nWhen remote receivers are combined as a sequence the corresponding messages are broadcast to all of them.\nWhen messages are combined as a sequence they are each sent to the receiver(s) in succession.\n\nThere is a subtle yet very important difference between local message passing (implicitly sent to `self`) and remote messages explicitly sent to the `self` variable and is to do with early versus late binding.\n\nEarly binding automatically occurs for local messages whenever there is a corresponding local handler. An early binding is forged at compile-time which greatly improves the efficiency of the resulting code by avoiding the search for a handler at run-time.\n\nLate bindings between a message and a class capable of handling it are forged at run-time whenever no local link can be found and for all messages sent remotely. It takes the form of a search up through the is-a hierarchy of classes starting at the class of the message receiver.\n\nIf you wish to avoid an early binding (and thus fool the compiler) send the same message explicitly to the `self` variable. When this is stated in the code a late binding will be performed at run-time.\n\nFor example, consider the definitions of `print_early/0` and `print_late/0` below which only differ in their manner of calling `print_contents/0`.\n\n```\nclass alpha .\n print_early :-\n print_header,\n print_contents,\n print_footer.\n\n print_late :-\n print_header,\n self <- print_contents,\n print_footer.\n\n print_contents :-\n ...\nend alpha\n\nclass beta .\n inherits alpha .\n\n print_contents :-\n ...\nend beta\n```\nA call to `print_early/0` for an instance of `beta` will use the definition of `print_contents/0` found in `alpha`, whereas a call to `print_late/0` for a similar instance will use the definition of `print_contents/0` found in `beta` itself.\n\nIf the definition of `print_contents/0` were removed from class `alpha` then the two calls would be equivalent since the compiler would not be capable of an early binding!\n\n**Procedural Message**\n\nA procedural message is handled by a method either defined in or inherited by the receiving class/instance.\n\n```\nprocedural_message\n → meta.procedural_message\n or name.method( sequence.term ) {arity > 0}\n or name.method {arity = 0}\n```\n\n**Remote Message Receiver**\n\nRemote receivers of messages are Prolog++ terms which are instantiated at run-time to classes or instances of classes.\n\n```\nreceiver\n → meta.receiver\n or term.instance\n or term.name.class\n```\n\n**Prolog++ Terms**\n\nA few examples of Prolog++ terms are:\n\n- `Buffer` % Prolog variable\n- `-12345.67890` % Prolog number\n- `& size` % Symbolic context\n \n `& ( aggregate_size / clock@time )`\n- `+( aggregate_size / clock@time )` % Arithmetic context\n \n `+Number+1`\n- `@ size` % Explicit local\n- `@ smallest( all instance class )` % functional messages\n- `clock @ time` % Remote functional\n- `@serves_teller @ status` % messages\n- `X suchthat X = instance teller` % Conditional term\n- `X suchthat ( X=1 ; X=2 )`\nall instance teller % All instantiations\n\n[ Queue | Queues ] % Non-empty list constructor\n\n[] % Empty list constructor\n\nself % Instantiates to self\n\nsuper % Instantiates to super\n\n% of current class\n\nclass % Class name of an object\n\nidentifier % Unique instance identifier\n\nmnemonic % Mnemonic name of instance\n\n$ fred % Instance with mnemonic name\n\ncategory user % All classes in the category\n\nsuper class teller % A super-class\n\nsub_class bank % A sub-class\n\nancestor_class customer_queue % Any ancestor class\n\ndescendant_class buffer % Any descendant class\n\ninstance teller % Any instance of the class\n\ncomposite_part Spoke % Composite-part of instance\n\nsuper_part Spoke % Super-part of an instance\n\nsub_part Wheel % A sub-part of an instance\n\nwheel # 1 % A specific sub-part of self\n\nX + Y % Arithmetic operators\n\n- Z\n\nmary % Symbolic atom\n\n% non-evaluable context\n\ntree( Left, Node, Right ) % Symbolic functor\n\n% non-evaluable context\n\nsize % Implicit local\n\n% functional messages\n\nsmallest( all instance class ) % when context is evaluable\n\n% Prolog++ Reference\nThe ordering given below is exactly the same ordering adopted by the Prolog++ compiler when parsing terms.\n\n```\nterm → prolog_variable {Prolog variable}\nor prolog_number {Prolog number}\nor & prolog_term {Force it to be a Prolog term}\nor + term {Evaluate term as an arithmetic expression}\nor @ functional_message {Local functional message}\nor receiver @ functional_message {Remote functional message}\nor term suchthat statement {Term such that statement holds}\nor all term {All instantiations of a term}\nor [ term | term ] {Non-empty list constructor}\nor [] {Empty list constructor}\nor self {Instantiate to the self variable}\nor super {Instantiate to a super of the defined class}\nor link {A structural, is-a or part-of link}\nor term binary_operator term {Binary arithmetic operator}\nor unary_operator term {Unary arithmetic operator}\nor prolog_atom {Prolog atom; not evaluable context}\nor name.functor(sequence.term) {Constructor; not evaluable context}\nor functional_message {Implicit functional message sent to self}\n```\n\nThere are three types of links in Prolog++. A structural link about an instance or class, an is-a hierarchy relating classes to each other and a part-of hierarchy relating instances of classes to eachother.\n\n```\nlink → structural_link\nor is_a_link\nor part_of_link\n```\n\n**Context**\n\nThe various contexts in which a term can occur are :-\n\n- **symbolic** Terms are considered purely symbolic, as in Prolog. This context is only attainable within the context switcher &.\n- **prolog++** Certain special terms, such as hierarchy links, are evaluated. This is the normal context for terms.\n- **evaluable** In addition to the prolog++ context all other atoms and functors (except arithmetic operators) are considered as implicit local messages. This context is used for the sub-terms of arithmetic expressions.\nIn addition to the evaluable context all arithmetic operators are considered evaluable by the Prolog built-in \\texttt{is/2}. This context is attainable within the explicit context switcher \\(+, arithmetic default attribute values (using \\texttt{is} rather than \\texttt{=}), arithmetic definitions of functional methods (again using \\texttt{is}) and calls to arithmetic Prolog built-ins such as \\texttt{is/2}, \\texttt{=/2} and \\texttt{tab/1}.\n\nNote that the context of a term is preserved for all of its immediate sub-terms. The only exception to this rule is that receivers of remote functional messages are always interpreted in the \\texttt{Prolog++} context.\n\n**Functional Message**\n\nA functional message will be handled by a functional method either defined in or inherited by the class of the receiver.\n\n\\[\n\\text{functional\\_message} \\rightarrow \\begin{array}{l}\n\\text{name.method} (\\text{sequence\\_term}) \\\\\n\\text{or name.method}\n\\end{array} \\quad \\{\\text{arity > 0}\\}\n\\]\n\nor\n\n\\[\n\\begin{array}{l}\n\\text{name.method} \\\\\n\\text{or name.method}\n\\end{array} \\quad \\{\\text{arity = 0}\\}\n\\]\n\nAs with procedural message passing, there is a subtle difference between local functional messages (early binding) and remote functional messages sent to the \\texttt{self} variable (late binding).\n\n**Structural Link**\n\nA structural link relates an instance, explicit or implicit, with either its class name, its unique identifier or with its mnemonic name assigned to it by the program when it is created.\n\n\\[\n\\text{structural\\_link} \\rightarrow \\begin{array}{l}\n\\text{explicit\\_structural\\_link} \\\\\n\\text{or implicit\\_structural\\_link}\n\\end{array} \\quad \\{\\text{relative to self variable}\\}\n\\]\n\n\\[\n\\text{explicit\\_structural\\_link} \\rightarrow \\\\\n\\begin{array}{l}\n\\text{class} \\quad \\text{term\\_instance} \\\\\n\\text{or identifier} \\quad \\text{term\\_instance} \\\\\n\\text{or mnemonic} \\quad \\text{term\\_instance}\n\\end{array} \\quad \\{\\text{Instance’s class name}\\}\n\\]\n\nor\n\n\\[\n\\begin{array}{l}\n\\text{class} \\quad \\text{term\\_instance} \\\\\n\\text{or identifier} \\quad \\text{term\\_instance} \\\\\n\\text{or mnemonic} \\quad \\text{term\\_instance}\n\\end{array} \\quad \\{\\text{Instance’s identifier}\\}\n\\]\n\nor\n\n\\[\n\\begin{array}{l}\n\\text{class} \\quad \\text{term\\_instance} \\\\\n\\text{or identifier} \\quad \\text{term\\_instance} \\\\\n\\text{or mnemonic} \\quad \\text{term\\_instance}\n\\end{array} \\quad \\{\\text{Instance’s mnemonic}\\}\n\\]\n\n\\[\n\\text{implicit\\_structural\\_link} \\rightarrow \\\\\n\\begin{array}{l}\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\end{array}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\n\nor\n\n\\[\n\\text{class} \\quad \\{\\text{self’s class name}\\} \\\\\n\\text{or identifier} \\quad \\{\\text{self’s identifier}\\} \\\\\n\\text{or mnemonic} \\quad \\{\\text{self’s mnemonic}\\}\n\\]\nIs-A Link\n\nIs-a links refer to classes in the class hierarchy or an instance of a class. They can explicitly refer to a class or instance or they can implicitly refer to the self variable.\n\n\\[\nis\\textunderscore a\\textunderscore link \\\\\n\\rightarrow \\text{explicit}\\textunderscore is\\textunderscore a\\textunderscore link \\\\\nor \\text{implicit}\\textunderscore is\\textunderscore a\\textunderscore link \\{\\text{relative to self variable}\\}\n\\]\n\nSome constructs (super\\textunderscore class and ancestor\\textunderscore class) reference classes higher up the is-a hierarchy whereas others (instance, sub\\textunderscore class, and descendant\\textunderscore class) reference classes and instances of classes lower down the is-a hierarchy.\n\nThe construct category refers to all the classes in the given category.\n\n\\[\n\\text{explicit}\\textunderscore is\\textunderscore a\\textunderscore link \\\\\n\\rightarrow \\text{category} \\quad \\text{term}\\textunderscore category \\{\\text{All classes in the category}\\} \\\\\nor \\text{super}\\textunderscore class \\quad \\text{term}\\textunderscore name\\textunderscore class \\{\\text{A super-class of a class}\\} \\\\\nor \\text{sub}\\textunderscore class \\quad \\text{term}\\textunderscore name\\textunderscore class \\{\\text{A sub-class of a class}\\} \\\\\nor \\text{ancestor}\\textunderscore class \\quad \\text{term}\\textunderscore name\\textunderscore class \\{\\text{An ancestor of a class}\\} \\\\\nor \\text{descendant}\\textunderscore class \\quad \\text{term}\\textunderscore name\\textunderscore class \\{\\text{A descendant of a class}\\} \\\\\nor \\text{instance} \\quad \\text{term}\\textunderscore name\\textunderscore class \\{\\text{An instance of a class}\\}\n\\]\n\n\\[\n\\text{implicit}\\textunderscore is\\textunderscore a\\textunderscore link \\\\\n\\rightarrow \\text{category} \\quad \\{\\text{All classes in self category}\\} \\\\\nor \\text{super}\\textunderscore class \\quad \\{\\text{A super-class of self}\\} \\\\\nor \\text{sub}\\textunderscore class \\quad \\{\\text{A sub-class of self}\\} \\\\\nor \\text{ancestor}\\textunderscore class \\quad \\{\\text{An ancestor class of self}\\} \\\\\nor \\text{descendant}\\textunderscore class \\quad \\{\\text{A descendant class of self}\\} \\\\\nor \\text{instance} \\quad \\{\\text{An instance of self}\\}\n\\]\n\nPart-Of Link\n\nPart-of links refer to instances in the run-time part-of hierarchy. They can explicitly refer to an instance or they can implicitly refer to the self variable.\n\n\\[\n\\text{part}\\textunderscore of\\textunderscore link \\\\\n\\rightarrow \\text{explicit}\\textunderscore part\\textunderscore of\\textunderscore link \\\\\nor \\text{implicit}\\textunderscore part\\textunderscore of\\textunderscore link \\{\\text{relative to self variable}\\}\n\\]\n\nNote that in contrast to is-a hierarchies which can be lattices (a class may have multiple super-classes) part-of hierarchies are strict (all instances have at most one super-instance). Consequently, the root of a part-of hierarchy is unique and is referred to as the composite\\textunderscore part.\nSome constructs (composite_part and super_part) refer to instances higher up the part-of hierarchy, whereas others (sub_part and #) refer to instances lower down the part-of hierarchy.\n\nThe composite_part is at the top or root of a part-of hierarchy.\n\nThe super_part is that unique instance directly above in the part-of hierarchy.\n\nA sub_part is any instance directly below in the part-of hierarchy.\n\nA specific sub-part of self can be referenced using the # construct, where the left argument refers to the name of the sub-part and the right argument refers to its occurrence number.\n\n\\[\n\\text{explicit_part_of_link} \\rightarrow \\text{composite_part} \\quad \\text{term.instance} \\\\\n\\quad \\text{or} \\quad \\text{super_part} \\quad \\text{term.instance} \\\\\n\\quad \\text{or} \\quad \\text{sub_part} \\quad \\text{term.instance} \\\\\n\\text{implicit_part_of_link} \\rightarrow \\text{composite_part} \\\\\n\\quad \\text{or} \\quad \\text{super_part} \\\\\n\\quad \\text{or} \\quad \\text{sub_part} \\\\\n\\quad \\text{or} \\quad \\text{term.name.part_class} \\ # \\ \\text{term.positive_number}\n\\]\n# Appendix B - Shorthand Declarations\n\nThis appendix summarises the various shorthand statements which can be made within Prolog++ class definitions.\n\n<table>\n<thead>\n<tr>\n<th>Shorthand Declaration</th>\n<th>Full Declaration</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>category</td>\n<td>categories</td>\n</tr>\n<tr>\n<td>inherit</td>\n<td>inherits</td>\n</tr>\n<tr>\n<td>part</td>\n<td>parts</td>\n</tr>\n<tr>\n<td>attributes</td>\n<td>private instance attributes</td>\n</tr>\n<tr>\n<td>private attributes</td>\n<td>private instance attributes</td>\n</tr>\n<tr>\n<td>public attributes</td>\n<td>public instance attributes</td>\n</tr>\n<tr>\n<td>instance attributes</td>\n<td>private instance attributes</td>\n</tr>\n<tr>\n<td>class attributes</td>\n<td>private class attributes</td>\n</tr>\n<tr>\n<td>attribute</td>\n<td>private instance attributes</td>\n</tr>\n<tr>\n<td>private attribute</td>\n<td>private instance attributes</td>\n</tr>\n<tr>\n<td>public attribute</td>\n<td>public instance attributes</td>\n</tr>\n<tr>\n<td>instance attribute</td>\n<td>private instance attributes</td>\n</tr>\n<tr>\n<td>class attribute</td>\n<td>private class attributes</td>\n</tr>\n<tr>\n<td>private instance attribute</td>\n<td>private instance attributes</td>\n</tr>\n<tr>\n<td>private class attribute</td>\n<td>private class attributes</td>\n</tr>\n<tr>\n<td>public instance attribute</td>\n<td>public instance attributes</td>\n</tr>\n<tr>\n<td>public class attribute</td>\n<td>public class attributes</td>\n</tr>\n<tr>\n<td>methods</td>\n<td>public methods</td>\n</tr>\n<tr>\n<td>public</td>\n<td>public methods</td>\n</tr>\n<tr>\n<td>private</td>\n<td>private methods</td>\n</tr>\n<tr>\n<td>method</td>\n<td>public methods</td>\n</tr>\n<tr>\n<td>public method</td>\n<td>public methods</td>\n</tr>\n<tr>\n<td>private method</td>\n<td>private methods</td>\n</tr>\n</tbody>\n</table>\nAppendix C - Prolog++ Operators\n\nThis appendix details the syntactic operators which are declared by Prolog++.\n\n<table>\n<thead>\n<tr>\n<th>Priority</th>\n<th>Type</th>\n<th>Operator Name</th>\n<th>Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1020</td>\n<td>fx</td>\n<td>public</td>\n<td>Declarations</td>\n</tr>\n<tr>\n<td>1020</td>\n<td>fx</td>\n<td>private</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>categories</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>category</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>inherit</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>inherit</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>parts</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>part</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>attributes</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>xfx</td>\n<td>attributes</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>attribute</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>xfx</td>\n<td>attribute</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>methods</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>xfx</td>\n<td>methods</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>fx</td>\n<td>method</td>\n<td></td>\n</tr>\n<tr>\n<td>1010</td>\n<td>xfx</td>\n<td>method</td>\n<td></td>\n</tr>\n<tr>\n<td>980</td>\n<td>fx</td>\n<td>inherited</td>\n<td>Default Attributes</td>\n</tr>\n<tr>\n<td>980</td>\n<td>xfx</td>\n<td>inherited</td>\n<td></td>\n</tr>\n<tr>\n<td>970</td>\n<td>fx</td>\n<td>forall</td>\n<td>Control Constructs</td>\n</tr>\n<tr>\n<td>970</td>\n<td>fx</td>\n<td>while</td>\n<td></td>\n</tr>\n<tr>\n<td>970</td>\n<td>fx</td>\n<td>repeat</td>\n<td></td>\n</tr>\n<tr>\n<td>960</td>\n<td>xfx</td>\n<td>do</td>\n<td></td>\n</tr>\n<tr>\n<td>960</td>\n<td>xfx</td>\n<td>until</td>\n<td></td>\n</tr>\n<tr>\n<td>950</td>\n<td>xfx</td>\n<td><-</td>\n<td>Procedural Message Passing</td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td>&=</td>\n<td>Noisy Attribute Assignment</td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td>:=</td>\n<td></td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td>+=</td>\n<td></td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td>-=</td>\n<td></td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td>*=</td>\n<td></td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td>/=</td>\n<td></td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td>&==</td>\n<td>Quiet Attribute Assignment</td>\n</tr>\n</tbody>\n</table>\n## Appendix C - Prolog++ Operators\n\n<table>\n<thead>\n<tr>\n<th>Priority</th>\n<th>Type</th>\n<th>Operator Name</th>\n<th>Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td><code>==</code></td>\n<td></td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td><code>+=</code></td>\n<td></td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td><code>-=</code></td>\n<td></td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td><code>*=</code></td>\n<td></td>\n</tr>\n<tr>\n<td>700</td>\n<td>xfx</td>\n<td><code>/=</code></td>\n<td></td>\n</tr>\n<tr>\n<td>650</td>\n<td>fy</td>\n<td><code>&</code></td>\n<td>Context Switching</td>\n</tr>\n<tr>\n<td>650</td>\n<td>fy</td>\n<td><code>+</code></td>\n<td></td>\n</tr>\n<tr>\n<td>600</td>\n<td>fy</td>\n<td><code>all</code></td>\n<td>Terms Qualifiers</td>\n</tr>\n<tr>\n<td>600</td>\n<td>xfx</td>\n<td><code>suchthat</code></td>\n<td></td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>class</code></td>\n<td>Program Delimiters</td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>end</code></td>\n<td></td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>identifier</code></td>\n<td>Structural Links</td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>mnemonic</code></td>\n<td></td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>super_class</code></td>\n<td>Is-A Links</td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>sub_class</code></td>\n<td></td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>ancestor_class</code></td>\n<td></td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>descendant_class</code></td>\n<td></td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>instance</code></td>\n<td></td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>composite_part</code></td>\n<td>Part-Of Links</td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>super_part</code></td>\n<td></td>\n</tr>\n<tr>\n<td>100</td>\n<td>fy</td>\n<td><code>sub_part</code></td>\n<td></td>\n</tr>\n<tr>\n<td>100</td>\n<td>yfx</td>\n<td><code>#</code></td>\n<td></td>\n</tr>\n<tr>\n<td>50</td>\n<td>fx</td>\n<td><code>$</code></td>\n<td>Mnemonic Name</td>\n</tr>\n<tr>\n<td>45</td>\n<td>yfx</td>\n<td><code>@</code></td>\n<td>Functional Message Passing</td>\n</tr>\n<tr>\n<td>45</td>\n<td>fy</td>\n<td><code>@</code></td>\n<td></td>\n</tr>\n</tbody>\n</table>\nAppendix D - Summary Of \"prolog_plus_plus\"\n\nThe table below summarises the public methods of the `prolog_plus_plus` class, and in each case indicates whether the message should be sent to a class or an instance of a class. In some cases, for example `compile/2`, it is irrelevant where the message is sent. In other cases, for example `isa_class/0` and `isa_instance/0`, it can be sent to either kind of object. Finally, certain messages such as `create/1` can only be sent to a specific kind of object as indicated in the self column.\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Self</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>compile / 2</code></td>\n<td></td>\n<td>The equivalent of the Prolog++ class compiler which allows new classes to be incorporated at run-time.</td>\n</tr>\n<tr>\n<td><code>create / 1</code></td>\n<td>class</td>\n<td>Create a new instance of the class.</td>\n</tr>\n<tr>\n<td><code>create / 2</code></td>\n<td>class</td>\n<td>Create a new instance of the class with some initial values for its attributes.</td>\n</tr>\n<tr>\n<td><code>create / 3</code></td>\n<td>class</td>\n<td>Create a new instance of the class with some initial values for its attributes and also give it a mnemonic name by which it can be referenced.</td>\n</tr>\n<tr>\n<td><code>delete / 0</code></td>\n<td>instance</td>\n<td>Delete this instance.</td>\n</tr>\n<tr>\n<td><code>delete_all / 0</code></td>\n<td>class</td>\n<td>Delete all instances of this class.</td>\n</tr>\n<tr>\n<td><code>dump / 1</code></td>\n<td>class</td>\n<td>Dump all instances of this class to a file.</td>\n</tr>\n<tr>\n<td><code>dump / 2</code></td>\n<td></td>\n<td>Dump all instances of the named classes to a file.</td>\n</tr>\n<tr>\n<td><code>duplicate / 1</code></td>\n<td>instance</td>\n<td>Duplicate this instance by creating a copy with the same attribute values.</td>\n</tr>\n<tr>\n<td><code>isa_class / 0</code></td>\n<td>class / instance</td>\n<td>Test whether the object is a class.</td>\n</tr>\n<tr>\n<td><code>isa_instance / 0</code></td>\n<td>class / instance</td>\n<td>Test whether the object is an instance of a class.</td>\n</tr>\n<tr>\n<td><code>kill / 0</code></td>\n<td>class</td>\n<td>Remove the definition of a class.</td>\n</tr>\n<tr>\n<td><code>load / 1</code></td>\n<td></td>\n<td>Load the previously saved class definitions from a file.</td>\n</tr>\n<tr>\n<td><code>optimize / 0</code></td>\n<td>class</td>\n<td>Optimize a class’s implementation.</td>\n</tr>\n<tr>\n<td><code>public / 1</code></td>\n<td>class</td>\n<td>Test or retrieve the name and arity of a public method for this class.</td>\n</tr>\n<tr>\n<td><code>reset / 0</code></td>\n<td>class / instance</td>\n<td>Reset the attributes of this class-instance back to their default values.</td>\n</tr>\n</tbody>\n</table>\n## Appendix D - Summary Of \"prolog_plus_plus\"\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Self</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>reset / 1</td>\n<td>class / instance</td>\n<td>Reset the named attribute of this class/instance back to its default value.</td>\n</tr>\n<tr>\n<td>restore / 1</td>\n<td></td>\n<td>Restore the previously saved class instances from a file.</td>\n</tr>\n<tr>\n<td>save / 1</td>\n<td>class</td>\n<td>Save this class’s definition to a file.</td>\n</tr>\n<tr>\n<td>save / 2</td>\n<td></td>\n<td>Save the definitions of the named classes to a file.</td>\n</tr>\n<tr>\n<td>when_error / 2</td>\n<td>class / instance</td>\n<td>A catchall method for handling errors which were raised by the system but not handled by the erroneous class.</td>\n</tr>\n</tbody>\n</table>\nAppendix E - Benchmark\n\nThis appendix details the relative performance of Prolog++ with respect to the underlying Prolog system. The benchmark used is an adaptation of the classical Prolog benchmark “Naive Reverse”.\n\nNaive reverse is a deliberately bad encoding of a program which reverses the elements of a list. It is a test of the LIPS (Logical Inferences Per Second) attained by a Prolog system, using a non-linear equation between the length of the list and the number of recursive calls which are made.\n\nThe intention of using this benchmark in a Prolog++ context is to test the performance of both the message passing system and the inheritance mechanism. It is not only a naive encoding of reverse, but also a deliberately bad structuring of the class hierarchy in which it is defined.\n\nThe Prolog Program\n\nNaive reverse is implemented by a recursive program \\( nrev/2 \\) which calls a second recursive program, \\( app/3 \\). These same Prolog definitions will be used when defining the Prolog++ methods.\n\n\\[\n\\begin{align*}\nnrev( [], [] ) & . \\\\\nnrev( [U|X], Z ) : - \\\\\n& \\hspace{1em} nrev( X, Y ), \\\\\n& \\hspace{1em} app( Y, [U], Z ). \\\\\napp( [], Z, Z ) & . \\\\\napp( [U|X], Y, [U|Z] ) : - \\\\\n& \\hspace{1em} app( X, Y, Z ).\n\\end{align*}\n\\]\n\nThe Prolog++ Classes\n\nThe following diagram illustrates the linear class hierarchy within which the various Prolog++ versions of the naive-reverse algorithm are implemented.\nThe essential difference between Prolog and Prolog++ in terms of performance is the inheritance mechanism of Prolog++. And so the purpose of designing the hierarchy this way is to create classes which define or inherit the two recursive methods, \\texttt{nrev/2} and \\texttt{app/3}, in different combinations. This is set out in the following table.\n\n<table>\n<thead>\n<tr>\n<th>Class</th>\n<th>\\texttt{nrev / 2}</th>\n<th>\\texttt{app / 3}</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>\\texttt{p_p}</td>\n<td>Inherit from \\texttt{prolog}</td>\n<td>Inherit from \\texttt{prolog}</td>\n</tr>\n<tr>\n<td>\\texttt{l_p}</td>\n<td>Defined locally</td>\n<td>Inherit from \\texttt{prolog}</td>\n</tr>\n<tr>\n<td>\\texttt{a_p}</td>\n<td>Inherit from \\texttt{ancestor}</td>\n<td>Inherit from \\texttt{prolog}</td>\n</tr>\n<tr>\n<td>\\texttt{l_l}</td>\n<td>Defined locally</td>\n<td>Defined locally</td>\n</tr>\n<tr>\n<td>\\texttt{a_l}</td>\n<td>Inherit from \\texttt{ancestor}</td>\n<td>Defined locally</td>\n</tr>\n<tr>\n<td>\\texttt{l_a}</td>\n<td>Defined locally</td>\n<td>Inherit from \\texttt{ancestor}</td>\n</tr>\n<tr>\n<td>\\texttt{a_a}</td>\n<td>Inherit from \\texttt{ancestor}</td>\n<td>Inherit from \\texttt{ancestor}</td>\n</tr>\n</tbody>\n</table>\n\n```prolog\nclass p_p.\ncategory benchmark.\nend p_p.\n\nclass l_p.\ncategory benchmark.\ninherit p_p.\nnrev( [], [] ).\nend l_p.\n```\n\n16\\texttt{prolog++ Reference}\nnrev( [Head|Tail], Rev ) :-\n nrev( Tail, TailRev ),\n app( TailRev, [Head], Rev ).\nend l_p.\n\nclass a_p.\ncategory benchmark.\ninherit l_p.\nend a_p.\n\nclass l_l.\ncategory benchmark.\ninherit a_p.\nnrev( [], [ ] ).\nnrev( [Head|Tail], Rev ) :-\n nrev( Tail, TailRev ),\n app( TailRev, [Head], Rev ).\n app( [], List, List ).\n app( [Head|Front], Back, [Head|List] ) :-\n app( Front, Back, List ).\nend l_l.\n\nclass a_l.\ncategory benchmark.\ninherit l_l.\napp( [], List, List ).\napp( [Head|Front], Back, [Head|List] ) :-\n app( Front, Back, List ).\nend a_l.\n\nclass l_a.\ncategory benchmark.\ninherit a_l.\nnrev( [], [ ] ).\nnrev( [Head|Tail], Rev ) :-\n nrev( Tail, TailRev ),\n app( TailRev, [Head], Rev ).\nend l_a.\n\nclass a_a.\ncategory benchmark.\ninherit l_a.\nend a_a.\n\nBenchmark Results\nThe listing below gives the results of the benchmark specified in the previous sections. The test was performed on a Macintosh LC475 with 8Mb of RAM running MacProlog32 version\n1.05. The application was assigned 5Mb of real memory, 2Mb of which formed the evaluation space.\n\nThe percentage figures compare the speed of Prolog++ with respect to the base speed of Prolog, and thus reflecting the overhead incurred by the inheritance mechanism.\n\n/* **************************** *\n* Machine: Macintosh LC475 *\n* Memory: 8Mb *\n* Application: MacProlog32 *\n* Version: 1.05 *\n* Memory: 5Mb *\n* Heap Space: 2Mb *\n* **************************** */\n\n?- bench( 500 ).\n\nInterpreted...\nDIRECT nrev/2 6300ms\nProlog nrev/2 6300ms 100%\nLocal nrev/2 Prolog app/3 6433ms 98%\nInherit nrev/2 Prolog app/3 6416ms 98%\nLocal nrev/2 Local app/3 6300ms 100%\nInherit nrev/2 Local app/3 6300ms 100%\nLocal nrev/2 Inherit app/3 6483ms 97%\nInherit nrev/2 Inherit app/3 6483ms 97%\n\nOptimized...\nDIRECT nrev/2 416ms\nProlog nrev/2 416ms 100%\nLocal nrev/2 Prolog app/3 516ms 81%\nInherit nrev/2 Prolog app/3 516ms 81%\nLocal nrev/2 Local app/3 416ms 100%\nInherit nrev/2 Local app/3 416ms 100%\nLocal nrev/2 Inherit app/3 416ms 100%\nInherit nrev/2 Inherit app/3 416ms 100%\n\nNo.1 : yes\nAppendix F - Glossary\n\nThe following table is a glossary of reserved words used in Prolog++.\n\n<table>\n<thead>\n<tr>\n<th>Reserved Word</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>^</td>\n<td>Existential term in set statements.</td>\n</tr>\n<tr>\n<td>!</td>\n<td>Prolog cut.</td>\n</tr>\n<tr>\n<td>#</td>\n<td>Infix operator relating the class name of a specific sub-part of self with that part's occurrence number.</td>\n</tr>\n<tr>\n<td>&</td>\n<td>Switch to a symbolic context.</td>\n</tr>\n<tr>\n<td>&=</td>\n<td>Noisy attribute assignment of a symbolic value.</td>\n</tr>\n<tr>\n<td>&==</td>\n<td>Quiet attribute assignment of a symbolic value.</td>\n</tr>\n<tr>\n<td>$</td>\n<td>Find an instance with a mnemonic name.</td>\n</tr>\n<tr>\n<td>*</td>\n<td>Infix operator relating the class name with its number of occurrences when defining a part.</td>\n</tr>\n<tr>\n<td>*=</td>\n<td>Noisy multiplication of an arithmetic attribute value.</td>\n</tr>\n<tr>\n<td>*==</td>\n<td>Quiet multiplication of an arithmetic attribute value.</td>\n</tr>\n<tr>\n<td>+</td>\n<td>Switch to an arithmetic context.</td>\n</tr>\n<tr>\n<td>+=</td>\n<td>Noisy addition to an arithmetic attribute value.</td>\n</tr>\n<tr>\n<td>+==</td>\n<td>Quiet addition to an arithmetic attribute value.</td>\n</tr>\n<tr>\n<td>,</td>\n<td>Separator for a conjunction of statements, messages or receivers, and for a sequence of parameters or arguments.</td>\n</tr>\n<tr>\n<td>-=</td>\n<td>Noisy subtraction from an arithmetic attribute value.</td>\n</tr>\n<tr>\n<td>-==</td>\n<td>Quiet subtraction from an arithmetic attribute value.</td>\n</tr>\n<tr>\n<td>-></td>\n<td>Separator for conditional statements.</td>\n</tr>\n<tr>\n<td>/</td>\n<td>Declaration of a procedural method's arity.</td>\n</tr>\n<tr>\n<td>/=</td>\n<td>Noisy division of an arithmetic attribute value.</td>\n</tr>\n<tr>\n<td>/==</td>\n<td>Quiet division of an arithmetic attribute value.</td>\n</tr>\n<tr>\n<td>:-</td>\n<td>Precedes statements in the definition of a method.</td>\n</tr>\n<tr>\n<td>:=</td>\n<td>Noisy attribute assignment of an arithmetic value.</td>\n</tr>\n<tr>\n<td>==</td>\n<td>Quiet attribute assignment of an arithmetic value.</td>\n</tr>\n<tr>\n<td>;</td>\n<td>Separator for a disjunction of statements.</td>\n</tr>\n<tr>\n<td><-</td>\n<td>Remote message passing symbol.</td>\n</tr>\n<tr>\n<td>Reserved Word</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>------------------</td>\n<td>-------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>=</td>\n<td>Regular equality used in the declaration of an attribute’s default value or the definition of a functional method.</td>\n</tr>\n<tr>\n<td>@</td>\n<td>Precedes a local functional message.</td>\n</tr>\n<tr>\n<td>@</td>\n<td>When used as an infix operator it is a remote functional message.</td>\n</tr>\n<tr>\n<td>all</td>\n<td>All values of a term.</td>\n</tr>\n<tr>\n<td>ancestor_class</td>\n<td>An ancestor of a class.</td>\n</tr>\n<tr>\n<td>attributes</td>\n<td>Declaration of the attributes defined in a class.</td>\n</tr>\n<tr>\n<td>bagof</td>\n<td>Collect solutions as a bag.</td>\n</tr>\n<tr>\n<td>categories</td>\n<td>Declaration of the categories in which a class exists.</td>\n</tr>\n<tr>\n<td>category</td>\n<td>Evaluates to the list of classes forming the named category.</td>\n</tr>\n<tr>\n<td>class</td>\n<td>Compulsory statement at the beginning of each class definition.</td>\n</tr>\n<tr>\n<td>class</td>\n<td>Prefix to attributes indicating the declaration of class rather than instance attributes.</td>\n</tr>\n<tr>\n<td>class</td>\n<td>The class name of an instance.</td>\n</tr>\n<tr>\n<td>composite_part</td>\n<td>The composite part of self at the top (or root) of its part-of hierarchy.</td>\n</tr>\n<tr>\n<td>descendant_class</td>\n<td>A descendant of a class.</td>\n</tr>\n<tr>\n<td>do</td>\n<td>Used with forall for universal statements and with while for repetitive statements.</td>\n</tr>\n<tr>\n<td>end</td>\n<td>Compulsory statement at the end of each class definition.</td>\n</tr>\n<tr>\n<td>fail</td>\n<td>Forced failure.</td>\n</tr>\n<tr>\n<td>findall</td>\n<td>Collect solutions as a list.</td>\n</tr>\n<tr>\n<td>forall</td>\n<td>Used with do for universal statements.</td>\n</tr>\n<tr>\n<td>identifier</td>\n<td>Unique identifier of an instance.</td>\n</tr>\n<tr>\n<td>inherits</td>\n<td>Declaration of one or more super-classes.</td>\n</tr>\n<tr>\n<td>instance</td>\n<td>Prefix to attributes indicating the declaration of instance rather than class attributes.</td>\n</tr>\n<tr>\n<td>instance</td>\n<td>An instance of a class.</td>\n</tr>\n<tr>\n<td>invalid</td>\n<td>Method name for contraint checking procedures before an attribute is assigned a new value.</td>\n</tr>\n<tr>\n<td>is</td>\n<td>Arithmetic equality used in the declaration of an attribute’s default value or the definition of a functional method.</td>\n</tr>\n<tr>\n<td>methods</td>\n<td>Declaration of the procedural and functional methods used to handle messages sent to a class (or any of its instances).</td>\n</tr>\n<tr>\n<td>mnemonic</td>\n<td>Mnemonic name of an instance assigned to it when created.</td>\n</tr>\n</tbody>\n</table>\nnot\n\nSound negation for statements.\n<table>\n<thead>\n<tr>\n<th><strong>Reserved Word</strong></th>\n<th><strong>Description</strong></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>parts</code></td>\n<td>Declaration of one or more component parts. Parts are created whenever an instance of the class is created.</td>\n</tr>\n<tr>\n<td><code>private</code></td>\n<td>Declaration of private attributes and methods not visible outside the class.</td>\n</tr>\n<tr>\n<td><code>public</code></td>\n<td>Declaration of public attributes and methods which are visible outside the class.</td>\n</tr>\n<tr>\n<td><code>repeat</code></td>\n<td>Repeat until failure.</td>\n</tr>\n<tr>\n<td><code>repeat</code></td>\n<td>Used with until for repetitive statements.</td>\n</tr>\n<tr>\n<td><code>self</code></td>\n<td>The instance to which the message being handled was originally sent.</td>\n</tr>\n<tr>\n<td><code>setof</code></td>\n<td>Collect solutions as a set.</td>\n</tr>\n<tr>\n<td><code>sub_class</code></td>\n<td>A sub-class of a class.</td>\n</tr>\n<tr>\n<td><code>sub_part</code></td>\n<td>A sub-part of <code>self</code>.</td>\n</tr>\n<tr>\n<td><code>suchthat</code></td>\n<td>Used to impose conditions on a term.</td>\n</tr>\n<tr>\n<td><code>super</code></td>\n<td>A super-class of the class being defined. This is used to force messages up the is-a hierarchy whilst preserving the value of the <code>self</code> variable.</td>\n</tr>\n<tr>\n<td><code>super_class</code></td>\n<td>A super-class of a class.</td>\n</tr>\n<tr>\n<td><code>super_part</code></td>\n<td>The super-part which <code>self</code> is a direct sub-part of.</td>\n</tr>\n<tr>\n<td><code>true</code></td>\n<td>Vacuous success.</td>\n</tr>\n<tr>\n<td><code>until</code></td>\n<td>Used with repeat for repetitive statements.</td>\n</tr>\n<tr>\n<td><code>when_assigned</code></td>\n<td>Method name for daemon procedures activated after an attribute is assigned a new value.</td>\n</tr>\n<tr>\n<td><code>when_created</code></td>\n<td>Method name for procedures activated after the creation of a new class instance.</td>\n</tr>\n<tr>\n<td><code>when_deleted</code></td>\n<td>Method name for procedures activated immediately before the deletion of a class instance.</td>\n</tr>\n<tr>\n<td><code>when_error</code></td>\n<td>Method name for procedures which handle errors.</td>\n</tr>\n<tr>\n<td><code>while</code></td>\n<td>Used with do for repetitive statements.</td>\n</tr>\n<tr>\n<td><code>\\+</code></td>\n<td>Negation-as-failure for statements.</td>\n</tr>\n</tbody>\n</table>\n### Index\n\n<table>\n<thead>\n<tr>\n<th>A</th>\n<th>D</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>abstract, 16</td>\n<td>daemon, 21, 28, 69, 111</td>\n</tr>\n<tr>\n<td>abstract data type, 40</td>\n<td>data encapsulation, 114</td>\n</tr>\n<tr>\n<td>abstraction, 15, 28</td>\n<td>database, 69, 88</td>\n</tr>\n<tr>\n<td>Abstraction, 17</td>\n<td>data-driven programming, 21, 28</td>\n</tr>\n<tr>\n<td>assignment, 111</td>\n<td>default value, 69, 111</td>\n</tr>\n<tr>\n<td>noisy, 112</td>\n<td>dynamic data structures, 24</td>\n</tr>\n<tr>\n<td>quiet, 112</td>\n<td></td>\n</tr>\n<tr>\n<td>attribute, 16, 111</td>\n<td></td>\n</tr>\n<tr>\n<td>assignment, 111</td>\n<td></td>\n</tr>\n<tr>\n<td>chaining, 115</td>\n<td></td>\n</tr>\n<tr>\n<td>statement, 111</td>\n<td></td>\n</tr>\n<tr>\n<td>Attribute, 17</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>B</th>\n<th>E</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>binding, 21, 30</td>\n<td>early binding, 21, 31</td>\n</tr>\n<tr>\n<td>early, 21, 31</td>\n<td>encapsulation, 15, 28</td>\n</tr>\n<tr>\n<td>forced, 31</td>\n<td>Encapsulation, 19</td>\n</tr>\n<tr>\n<td>late, 21, 31</td>\n<td></td>\n</tr>\n<tr>\n<td>broadcasting messages, 27</td>\n<td></td>\n</tr>\n<tr>\n<td>built-in procedures</td>\n<td></td>\n</tr>\n<tr>\n<td>summary, 161</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>C</th>\n<th>F</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>C++, 34</td>\n<td>fault diagnosis, 98</td>\n</tr>\n<tr>\n<td>classes, 35</td>\n<td>function</td>\n</tr>\n<tr>\n<td>data abstraction, 37</td>\n<td>arithmetic, 119</td>\n</tr>\n<tr>\n<td>encapsulation, 36</td>\n<td>evaluation of, 118</td>\n</tr>\n<tr>\n<td>environment, 35</td>\n<td>statement, 117</td>\n</tr>\n<tr>\n<td>inheritance, 36</td>\n<td>functions, 117</td>\n</tr>\n<tr>\n<td>message, 35</td>\n<td></td>\n</tr>\n<tr>\n<td>objects, 36</td>\n<td></td>\n</tr>\n<tr>\n<td>operator overloading, 36</td>\n<td></td>\n</tr>\n<tr>\n<td>polymorphism, 36</td>\n<td></td>\n</tr>\n<tr>\n<td>private, 35, 37</td>\n<td></td>\n</tr>\n<tr>\n<td>public, 35, 37</td>\n<td></td>\n</tr>\n<tr>\n<td>class, 15</td>\n<td></td>\n</tr>\n<tr>\n<td>hierarchy, 15</td>\n<td></td>\n</tr>\n<tr>\n<td>Class, 17</td>\n<td></td>\n</tr>\n<tr>\n<td>class hierarchy, 15</td>\n<td></td>\n</tr>\n<tr>\n<td><strong>Class Hierarchy</strong>, 19, 25</td>\n<td></td>\n</tr>\n<tr>\n<td>classophobia, 33</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>L</th>\n<th>M</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>LAP, 26</td>\n<td>message, 16, 19, 27</td>\n</tr>\n<tr>\n<td>late binding, 21, 31</td>\n<td>broadcasting, 27, 116</td>\n</tr>\n<tr>\n<td>forced, 31</td>\n<td>handler, 114</td>\n</tr>\n<tr>\n<td>logic programming, 23</td>\n<td>local, 115</td>\n</tr>\n<tr>\n<td>LOS, 26</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n---\n\n*Prolog++ Reference*\npassing, 19, 115\nMessage, 20\nmessage broadcasting, 40\nmessages, 115\nmethod, 16, 114\n private, 114\n statement, 114\nMethod, 17, 19\nmultiple inheritance, 21, 29\nmyself, 107\n\nO\n\nOOPS definitions\nabstract, 16\nabstraction, 15\nattribute, 16\nclass, 15\nclass hierarchy, 15\nencapsulation, 15\ninheritance, 15\ninstance, 15\nmessage, 16\nmethod, 16\nOOPS, 16\npolymorphism, 16\nprivate, 16\npublic, 16\noperators, 162\n\nP\n\npolymorphism, 16, 27, 40, 116\nPolymorphism, 19\nprivate, 16, 28, 106\nPrivate, 17\nprivate/1, 114\nprogram, 106\nprogram statement, 106\n attribute, 111\n function, 117\n method, 114\nProlog, 23\n data structures, 24\n variables, 23\nProlog++\n abstraction, 28\ndata-driven programming, 28\n encapsulation, 28\n inheritance, 27, 28\n message broadcasting, 27\n polymorphism, 27\n singular inheritance, 28\npublic, 16, 28\nPublic, 34\n\nR\n\nresource management, 69\n\nS\n\nself, 107\nsimulation, 40\nsingular inheritance, 20, 28\nSmalltalk, 32\n classes, 33\n data abstraction, 34\n encapsulation, 34\n environment, 33\n inheritance, 34\n messages, 33\n cascading, 33\n methods, 33\n objects, 34\n polymorphism, 34\nsub, 107\nsubs, 107\nsuper, 107, 108\n supers, 107\nsyntax, 106, 143\n formal, 143\n operators, 162\n\nT\n\ntrigger, 28\nType-free variables, 23\n\nV\n\nvariable\n instance, 107, 140\n logical, 106"}}},{"rowIdx":81,"cells":{"id":{"kind":"string","value":"f7cc1d5ac95dc0ccc5ed7beced1425ed8910fa75"},"text":{"kind":"string","value":"THESIS\n\nREQUIREMENTS ANALYSIS AND DESIGN OF A DISTRIBUTED ARCHITECTURE FOR THE COMPUTER AIDED PROTOTYPING SYSTEM (CAPS)\n\nby\n\nGary L. Kreeger\n\nSeptember 1999\n\nThesis Advisor: Man-Tak Shing\n\nApproved for public release; distribution is unlimited.\n**REPORT DOCUMENTATION PAGE**\n\n1. AGENCY USE ONLY (Leave blank)\n2. REPORT DATE\n September 1999\n3. REPORT TYPE AND DATES COVERED\n Master's Thesis\n\n4. TITLE AND SUBTITLE: REQUIREMENTS ANALYSIS AND DESIGN OF A\n DISTRIBUTED ARCHITECTURE FOR THE COMPUTER AIDED PROTOTYPING\n SYSTEM (CAPS)\n\n5. FUNDING NUMBERS\n\n6. AUTHOR(S) Kreeger, Gary L.\n\n7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)\n Naval Postgraduate School\n Monterey, CA 93943-5000\n\n8. PERFORMING ORGANIZATION REPORT NUMBER\n\n9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)\n\n10. SPONSORING/MONITORING AGENCY REPORT NUMBER\n\n11. SUPPLEMENTARY NOTES\n The views expressed in this thesis are those of the author and do not reflect\n the official policy or position of the Department of Defense or the U.S. Government.\n\n12a. DISTRIBUTION/AVAILABILITY STATEMENT:\n Approved for public release; distribution is unlimited.\n\n12b. DISTRIBUTION CODE:\n\n13. ABSTRACT (maximum 200 words)\n\n The Computer Aided Prototyping System (CAPS) developed at the Naval Postgraduate School is a\n powerful Computer Aided Software Engineering (CASE) tool for examining requirements and timing constraints\n for hard real-time systems. However, it remains a stand-alone system. Even if it is running on machines in\n multiple locations, there is no way to coordinate the efforts between the different locations. In today's software\n development environment, that proves to be a significant disadvantage. Additionally, providing support for more\n than just hard real-time software development would tremendously enhance CAPS.\n\n Our analysis details the requirements needed to make a distributed CAPS feasible. A distributed CAPS\n functioning over a network in a coordinated manner would be an invaluable asset to those developing software\n today, especially in the Department of Defense (DOD). Our work also produced an initial design architecture\n based on a three tiered client-server model and utilizing Java and the Common Object Request Broker\n Architecture (CORBA). The Java/CORBA combination greatly simplifies deploying a distributed CAPS over any\n heterogeneous network. Our preliminary implementation of CAPS with a NT client and a Solaris server\n demonstrates the efficacy of this design.\n\n14. SUBJECT\n Software Engineering, Distributed Applications, Computer Aided Prototyping, CORBA\n\n15. NUMBER OF PAGES\n 183\n\n16. PRICE CODE\n UL\n\n17. SECURITY CLASSIFICATION OF REPORT\n Unclassified\n\n18. SECURITY CLASSIFICATION OF THIS PAGE\n Unclassified\n\n19. SECURITY CLASSIFICATION OF ABSTRACT\n Unclassified\n\n20. LIMITATION OF ABSTRACT\n UL\n\nNSN 7540-01-280-5500\n\nStandard Form 298 (Rev. 2-89) Prescribed by ANSI Std. 259-18 298-102\nApproved for public release; distribution is unlimited.\n\nREQUIREMENTS ANALYSIS AND DESIGN OF A DISTRIBUTED ARCHITECTURE FOR THE COMPUTER AIDED PROTOTYPING SYSTEM (CAPS)\n\nGary L. Kreeger\nCommander, United States Navy\nB.A., Austin College, 1982\n\nSubmitted in partial fulfillment of the requirements for the degree of\n\nMASTER OF SCIENCE IN COMPUTER SCIENCE\n\nfrom the\n\nNAVAL POSTGRADUATE SCHOOL\nSeptember 1999\n\nAuthor: \nGary L. Kreeger\n\nApproved by: \nMan-Tak Shing, Thesis Advisor\n\nChris Eagle, Second Reader\n\nDan Boger, Chairman,\nComputer Science Department\nTHIS PAGE INTENTIONALLY LEFT BLANK\nABSTRACT\n\nThe Computer Aided Prototyping System (CAPS) developed at the Naval Postgraduate School is a powerful Computer Aided Software Engineering (CASE) tool for examining requirements and timing constraints for hard real-time systems. However, it remains a stand-alone system. Even if it is running on machines in multiple locations, there is no way to coordinate the efforts between the different locations. In today’s software development environment, that proves to be a significant disadvantage. Additionally, providing support for more than just hard real-time software development would tremendously enhance CAPS.\n\nOur analysis details the requirements needed to make a distributed CAPS feasible. A distributed CAPS functioning over a network in a coordinated manner would be an invaluable asset to those developing software today, especially in the Department of Defense (DOD). Our work also produced an initial design architecture based on a three tiered client-server model and utilizing Java and the Common Object Request Broker Architecture (CORBA). The Java/CORBA combination greatly simplifies deploying a distributed CAPS over any heterogeneous network. Our preliminary implementation of CAPS with a NT client and a Solaris server demonstrates the efficacy of this design.\nTHIS PAGE INTENTIONALLY LEFT BLANK\n# TABLE OF CONTENTS\n\nI. INTRODUCTION .................................................................................................................. 1\n A. BACKGROUND .................................................................................................................. 1\n B. THESIS OBJECTIVES ...................................................................................................... 3\n 1. Requirements for a Distributed CAPS ........................................................................... 4\n 2. Design Issues for a Distributed CAPS ......................................................................... 5\n\nII. BACKGROUND .................................................................................................................. 9\n A. WHY PROTOTYPE AT ALL? ............................................................................................. 9\n 1. The Waterfall Method .................................................................................................. 10\n 2. The Spiral Model ......................................................................................................... 13\n 3. Summary of Prototyping Goals .................................................................................. 15\n B. THE EVOLUTION OF PROTOTYPING SYSTEMS ............................................................ 16\n 1. Automatic Code Generators ....................................................................................... 16\n 2. Requirements Specification Systems .......................................................................... 17\n 3. Executable Specification Language ............................................................................ 17\n 4. Megaprogramming Systems ...................................................................................... 18\n 5. Prototyping Languages ............................................................................................... 18\n 6. Computer Aided Software Engineering (CASE) Tools .................................................. 19\n 7. Prototyping Systems Summary .................................................................................. 20\n C. CAPS DEVELOPMENT .................................................................................................... 21\n D. PROTOTYPING RISKS ................................................................................................... 22\n E. THE FUTURE .................................................................................................................. 22\n\nIII. REQUIREMENTS ANALYSIS FOR DEPLOYING CAPS IN A DISTRIBUTED ENVIRONMENT .................................................................................................................. 25\n A. CREATING A WELL DESIGNED SYSTEM ....................................................................... 25\n 1. UML Overview ............................................................................................................. 25\n a. Visualizing ............................................................................................................... 26\n b. Specifying ................................................................................................................ 26\n c. Constructing ............................................................................................................ 26\n d. Documenting .......................................................................................................... 27\n 2. Using UML to Redesign CAPS ................................................................................... 27\n B. METHODOLOGY SPECIFICS ......................................................................................... 28\n 1. System Functions ........................................................................................................ 28\n 2. Use Cases .................................................................................................................. 28\n 3. Conceptual Model ..................................................................................................... 29\n C. REQUIREMENTS ANALYSIS RESULTS ........................................................................ 30\n 1. Functional Requirements ......................................................................................... 30\n 2. High-level Use Cases ............................................................................................... 35\n 3. Expanded Uses Cases .............................................................................................. 41\n 4. Conceptual Diagrams .............................................................................................. 42\n\nvii\nLIST OF FIGURES\n\nFigure 2.1 The Importance of Early Requirement Validation Figure ......11\nFigure 2.2 Types of Errors in Requirements ..................................12\nFigure 2.3 Spiral Model ..................................................................14\nFigure 3.1 Conceptual Diagram - Network Support .........................44\nFigure 3.2 Conceptual Diagram - Reuse Support ..............................45\nFigure 3.3 Conceptual Diagram - Management Support ....................46\nFigure 3.4 Conceptual Diagram - Execution ..................................47\nFigure 3.5 Conceptual Diagram - User Inputs .................................48\nFigure 4.1 OMG Reference Model Architecture ..............................54\nFigure 4.2 CORBA ORB Architecture ............................................55\nLIST OF TABLES\n\nTable 3.1 User Input Functions-Requirements Analysis ........................................30\nTable 3.2 User Input Functions-System Modeling/Specification .................................31\nTable 3.3 User Input Functions-Prototype Development ...........................................31\nTable 3.4 User Input Functions-Reuse ......................................................................32\nTable 3.5 System Administration .............................................................................33\nTable 3.6 Network Support .........................................................................................33\nTable 3.7 Project Management .................................................................................34\nTable 3.8 Conceptual Diagram Components .............................................................42\nACKNOWLEDGEMENTS\n\nI would like to sincerely thank Professor Man-Tak Shing and LCDR Chris Eagle for all their great ideas and guidance and for always having time to talk. I’d like thank Erik and Lamb for making me laugh when I always needed to. Last, I want to give my deepest appreciation to Katie for her unyielding support which made this thesis possible.\nI. INTRODUCTION\n\nIn recent years, more and more attention has been placed on developing better methods for the production of software. This results from the fact that hardware has simultaneously dropped in price dramatically and increased in performance while software has continued to be plagued by cases of bug prone productions, incomplete designs that don't function as desired and in some high profile incidents, software projects that had to be abandoned as hopeless. Often the culprit in these cases is a poor understanding of the user's requirements. This leads to incomplete or erroneous functionality in a software system that, with traditional methods, remains undiscovered until near the end of development when the user sees a working product for the first time. At this point, it is difficult and very expensive to correct requirement deficiencies. This situation led to the concept of prototyping software systems early in development so that requirements could be validated in time to easily make changes before problems became too deeply rooted. The first prototypes were largely coded manually. This made timely analysis difficult. Today, technology has matured to the point that automatic generation of prototypes is not only feasible but practical as well [CHAV95]. As the software development process has become more and more distributed, a need has arisen for distributed prototyping tools.\n\nA. BACKGROUND\n\nIn the traditional waterfall method of software development, requirements analysis and subsequent design were done before little, if any, actually coding was done. This helped to preclude the analysis and design being unduly influenced by\nimplementation constraints or biases. However, the drawback was that once promulgated, these decisions tended to be seen as set in stone. Even if they were reviewed later in the development cycle, it was difficult to update them. The major drawback though was that the customer only saw their requirements on paper. Possibly they had some conceptual drawings of an interface, but clearly that was not interactive at all. This led to customers who didn't get hands-on experience with their product until some sort of alpha version was developed. At this point the project was nearing completion and making fundamental changes, even simple ones, was very difficult. The result was expensive software that did not perform as the customer actually wanted it to and was probably delivered late. Clearly there had to be a better way to develop software.\n\nThat better way is prototyping. The idea is simple but powerful. Take the customer's requirements and create executable models to allow customers to clarify the desired system functionality. The tremendous advantage of this was the customer had a model not drawn on paper but one that could be interacted with on the computer. The developer could use a prototype to help explain the system design to the customer. Customer feedback was immediate and clarification of requirements by the customer much clearer. Since the investment of time and effort to produce a prototype was relatively small and it was early in the development process, changes that the customer wanted were easily accommodated. However, the prototype was still largely a hand-coded product. In order to reach its full potential, prototyping would have to become even more timely.\nAutomation was the only way for prototyping to become timelier. This necessity led to the development of the Computer Aided Prototyping System (CAPS) at the Naval Postgraduate School [LUQI88a,LUQI96]. The goal of CAPS is to improve the efficiency and accuracy of evolutionary software development by providing tools that make it possible for the developer to quickly and systematically construct and execute prototypes [DAMP92]. Much effort has gone into achieving the goal of automating the prototyping process and the results thus far are impressive. However, the biggest drawback to wider use of CAPS is that it remains a local system. This makes it difficult, if not impossible, to coordinate a large project with many designers. The reality of software production today is that a team that is geographically dispersed will most likely carry out the development of any particular system. Thus to unlock the full potential of CAPS, it is necessary to implement it in a distributed, network environment.\n\nB. THESIS OBJECTIVES\n\nA significant amount of research has gone into developing CAPS. However, today CAPS is implemented on a stand alone UNIX system. This arrangement has served the research done to date quite well. To unlock the potential that exists in CAPS though, it must become more versatile. This means making CAPS available to a wider client base and this requires distributing it over a network. That could be simply a local area network (LAN) but that would only be a half step. It should also be deployable over a wide area network (WAN) since more and more collaborators on projects are located over physically remote sites. Any discussion about a LAN or especially a WAN must first acknowledge the certainty that the network will be heterogeneous. Thus\nmany of the assumptions made when CAPS was a stand-alone system will no longer be valid.\n\nAny architecture and subsequent implementation of CAPS on a network will have to address many requirements. The high reliability required in a prototyping system such as CAPS will be an even greater challenge in a distributed environment. Isolating errors in a stand-alone system is relatively easy when compared to the same process in a distributed environment. As the distributed environment grows, high availability becomes more important. Since the network is sure to be heterogeneous, the correctness of the system will depend on maintaining the consistency and integrity of the data as it is passed throughout an environment that includes a variety of operating systems, machine hardware and programming languages.\n\nThese are only a few of the more obvious obstacles to providing a distributed implementation of CAPS. Some of the problems will have straightforward, readily available answers. But due to the uniqueness of CAPS, many will not. Thus a comprehensive requirements analysis is imperative if CAPS is to be successfully deployed in a distributed environment.\n\n1. Requirements for a Distributed CAPS\n\nWith CAPS operating on a stand-alone UNIX system, it is possible to make many simplifying assumptions. Consequently, much of the current design will have to be reexamined. However, distributing CAPS is more complicated than simply taking the current system and putting it on a network. Before creating a design and architecture, the requirements themselves must be reevaluated. It is possible, indeed almost certain, that adapting CAPS to a distributed environment will alter many of the requirements that\nled to the creation of CAPS. Below are characteristics that need to included in the requirements analysis for distributing CAPS.\n\nWhat will be the nature of the actual physical environment? The degree of transparency must be decided. It is assumed that any distributed network will be heterogeneous but that doesn't mean that it will necessarily support any hardware or operating system that is connected to the network. Exactly what will be supported must be determined. Will it be installed on a LAN, WAN or some other network design? The amount of fault tolerance must be considered. System performance encompasses several issues. What is the minimum system hardware requirement to be enforced? The amount of latency that can be tolerated will affect the design and must be determined. Is scalability important to a distributed CAPS? It may be possible to decide that there are practical limits to the size of any useful implementation. As with any distributed system, security becomes a much bigger concern. Certainly cost is a consideration if you want to widely deploy any system, as is ease of use. Ease of use will also include questions about the effectiveness of training. A key requirement will be the constraints placed on what language reusable components can be written in. The healthy population of the database of reusable components is critical to CAPS reaching its full potential, thus the impediments to achieving that goal should be as few as possible.\n\n2. **Design Issues for a Distributed CAPS**\n\nThe nature of the distributed architecture will determine many of the design specifics. What type of architecture is best for CAPS? The architecture can be centralized, replicated throughout the network, or something in between. One of the\nmost fundamental design questions deals with how to handle components. This is much more complicated and less straightforward than in an undistributed system. How different components communicate with each other must be decided and will be affected by where they are located. Closely associated with the question of communication is what degree of mobility components will have and how they will be synchronized. Components are not the only entities that must specify their behavior in a distributed environment. Data itself is severely influenced by the architectural design. What sort of access will users have to data in a distributed CAPS? It can be shared, distributed or some form of shared-distributed [PROT96]. The details of how persistent storage will operate must be consistent with the handling of data.\n\nThere is a collection of other design questions to be answered in addition to how components and data will behave. The mechanism for creation and subsequent destruction of process and threads must be specified. This must accommodate not only a distributed environment but the possibility of multi-processor machines within the network. With processes and data distributed throughout a network, provisions must be made for handling distributed exceptions. At the management level, distributed CAPS must provide for version control and merging of distributed data. The strategy for dealing with both of these functions will be critical to successfully distributing CAPS. It will be futile to take advantage of the improved productivity offered by distributing CAPS if a coherent, correct prototype is not the ultimate product.\n\nA final consideration throughout the design process will be how or whether to reuse parts of the existing CAPS system. Clearly, some of it must be radically reengineered to support operations in a distributed network. However, much of the\ncurrent system may be useable in a distributed environment. Deciding what to keep unchanged and what to alter will be a constant balancing act. Any design must weigh the performance improvement associated with any change to the existing system against the cost of implementing that change.\nII. BACKGROUND\n\nThe history of software prototyping shares many similarities with the larger subject of software engineering, and indeed with most emerging technologies. It has been the source of great debate and confusion as software engineers sought to define exactly what it was and how best to use it. Indeed, the debate and research continues unabated into what exactly constitutes the best way to prototype and how to use it most effectively. The one point that most software engineers agree upon is that the larger, increasingly complex systems of today can be more efficiently produced with the aid of prototypes. Thus, before looking too far into the future it would be valuable to take a look at the past and how we got to where we are today in working with software prototypes.\n\nA. WHY PROTOTYPE AT ALL?\n\nAs computer languages came into existence, a rather simple method of developing software emerged. It was simply code and fix. A programmer would sit down and write a program, run it and then try to fix the things that didn't work. This approach was sufficient for small, relatively uncomplicated programs. But just as structured programming emerged to bring some cohesion to writing computer programs and in turn was replaced by the object oriented paradigm, the code and fix method of developing software systems was destined to fall by the way side. As systems became more complicated and ever larger, one person was no longer able to do the amount of work required. The amount of work was even more than small groups of software engineers and programmers could handle. As more people became involved in the\nprocess, it became clear that a better process was needed to create software systems. This led to the waterfall model of software development.\n\n1. The Waterfall Method\n\nThe waterfall model, defined by Royce [ROYC76] and refined by Boehm [BOEH76], introduced some rigor and discipline to the development process. No longer was code written in isolation from the bigger picture of what the system should actually do and then tested to see where it didn't work. Instead, the process was partitioned into well-defined development phases. Now there would be a comprehensive investigation to determine the requirements of the system, followed by design, implementation and finally testing before a system was released. In theory, this systematization of the process of producing software systems would result in improved productivity and better systems. To a large degree it succeeded in achieving the desired results. However, as systems continued to swell in size and complexity, it became clear that there existed some serious shortcomings with the waterfall method as well.\n\nForemost amongst these is the need to establish the requirements for the systems at the beginning of the development process. This is true for several reasons. Customers may not know exactly what they want the final system to really do or they may not clearly define their needs to the developers. Also, requirements can change due to alterations in the environment that the system will operate in, even while the system is being developed. Also, during system development, requirements can emerge that were overlooked or unanticipated initially. Whatever the reasons for changing, incomplete or missing requirements, one thing was for certain. Inaccurate requirements, left unchecked, propagated throughout the entire system and resulted in software systems that were late, over budget and performed poorly. Sometimes entire\nprojects were abandoned as beyond salvaging, as it became clear that they would never perform as expected. As seen in Figures 2.1 and 2.2, most of the problems experienced by systems result from inadequacies with the requirements and the later these deficiencies are corrected, the more expensive the fix becomes.\n\n![Diagram showing time spent in each phase and source of errors.]\n\n<table>\n<thead>\n<tr>\n<th>Stage</th>\n<th>Relative Cost of Repair</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Requirements</td>\n<td>1</td>\n</tr>\n<tr>\n<td>Design</td>\n<td>5</td>\n</tr>\n<tr>\n<td>Implementation</td>\n<td>10</td>\n</tr>\n<tr>\n<td>Unit Test</td>\n<td>20</td>\n</tr>\n<tr>\n<td>Acceptance</td>\n<td>50</td>\n</tr>\n<tr>\n<td>Maintenance</td>\n<td>100</td>\n</tr>\n</tbody>\n</table>\n\n**Figure 2.1 The Importance of Early Requirement Validation From [WOOD92]**\nFigure 2.2 Types of Errors in Requirements From [WOOD92]\n\nThe dilemma confronted by software developers with the waterfall model is aptly summed up in a report of the Defense Science Board Task Force on Military Software [DSB87].\n\nWe believe that users cannot, with any amount of effort and wisdom, accurately describe the operational requirements for a substantial software system without testing by real operators in an operational environment, and iteration on the specification. The systems built today are just too complex for the mind of man to foresee all the ramifications purely by the exercise of the analytic imagination.\nThis inability to completely anticipate all the requirements of system being developed lead to the creation of the spiral model [BOEH86] for software engineering.\n\n2. The Spiral Model\n\nThe spiral model, shown in Figure 2.3, moved the software development process from being documentation driven to one that is risk driven. In other words, instead of concentrating on completing the current phase in the development process before moving on to the next phase, you start by identifying the areas with the highest risk and as you develop a strategy for dealing with each one you then tackle the next lower area of risk. In essence you have a series of mini-waterfall evolutions but the power of the spiral method is that the requirements do not have to all be known before you start. Instead, you are defining them as you \"spiral\" through iteration after iteration, solving the hardest part of the system first and working your way to the areas of relatively less risk. Prototyping certainly is not required to execute the spiral model of development but it can dramatically improve the efficiency of the model. If the problem domain of the system being developed is low risk and well understood, it is possible to use what essentially amounts to a waterfall method of development. However, this is usually true only in uninteresting or trivial systems. In most cases a system is being created for an area that is not well understood, either by user or developers or maybe even both. Especially in the Department of Defense, this is often the case since many of the systems being developed are at the cutting edge of technology or beyond.\n\nThis is when the power of prototyping becomes clear. By allowing developers to present a mock-up of a system early in development, it is possible to get user feedback in a much more timely manner. This capability makes the spiral method of development\nmuch more effective since developers can now produce prototypes throughout the iterative development process and use the responses from the ultimate end user to continually refine the requirements. Thus when a final product is delivered, it is much more likely that the system will function as expected. This avoids a great deal of maintenance effort and expense that normally goes into modifying a delivered system in order to get it to do what the user really wanted in the first place.\n\nFigure 2.3 Spiral Model From [BOEH86]\nThis leads to consideration about what the ultimate role of the prototype is within the development process. While there are many variations and differing names, there are two basic purposes for prototypes, both within and outside the spiral model. Prototypes can be either exploratory or implementation oriented. Exploratory, also referred to as experimental or evaluative, prototypes are used to better understand some specific requirement or limitation. The intention is that they will be used and discarded after providing the required information and insight. Implementation prototypes on the other hand will ultimately become the actual system being developed. The biggest practical difference is simply how they are created. An exploratory prototype which will be \"thrown away\" after being used does not have to concern itself too much with things such as efficiency, robustness, readability, etc. It must only function in a manner that allows the developers, and possibly the users, to better understand the question under consideration. The implementation oriented prototype must perform in such a manner that the code it produces is of production quality.\n\n3. Summary of Prototyping Goals\n\nNo matter which approach to prototyping a development team uses, there are some general goals for prototyping that pertain to any software system development effort. Not every goal is necessarily applicable to every prototype, but they provide a framework for how prototyping can improve any development effort.\n\n- Help systems engineers, users and developers to better understand and communicate about the environment and specific problem requirements and to transfer design intent amongst themselves;\n• Demonstrate what is actually feasible, a specific system behavior or some element of the proposed system's performance;\n\n• Use as a mechanism for getting the users involved earlier than in traditional software development processes thus potentially creating a more useful system; and\n\n• Get a production version, of improved quality, completed in less time than with traditional methods without prototyping.\n\nB. THE EVOLUTION OF PROTOTYPING SYSTEMS\n\nExactly what constitutes a prototype and how you create one has been the subject of much debate and research. While there will probably never be one definitive prototype model that everyone accepts, it is illuminating to review a sampling of the systems that have been fielded. Not every system evaluated meets the definition of a prototype but they all have contributed to the evolution of prototyping systems.\n\n1. Automatic Code Generators\n\nOne of the earliest attempts at improving the software development process was the idea of having program source code automatically generated. Any productive and useful prototyping system today will have to incorporate some automatic code generation or it will be too cumbersome to be effective. The success of current prototyping systems owes much to the work done on automatic code generation. However, automatic code generation by itself as a stand-alone development method has many shortcomings. Assuming that you are confident that the code being generated is actually correct, there is the question of what it was derived from. Often, automatic code generation amounts to not much more than instantiating a template\naccording to the user's specifications. The better code generation systems such as Graphical Approach to Modeling and Building Interactively a Technical System (GAMBITS) [POWE96] are still restricted to a fairly narrow domain. They start small using rigid models and keep extending the systems being developed until a useful system is produced. However, useful prototypes are not part of the process and it is still up to the developers, users and system analysts to ensure that correct requirements are implemented. Therefore they are limited outside their respective problem domain.\n\n2. Requirements Specification Systems\n\nThe goal of a requirements specification system is to capture the complete requirements for a system. Often poor communications result in missed, inaccurate or incomplete requirements and thus the specifications on which implementation will ultimately depend are flawed. A requirements specification system will not produce a prototype but the research done in this area has improved current prototyping systems as well as automatic code generating systems and executable specification languages.\n\n3. Executable Specification Language\n\nExecutable specification languages, such as PAISLey [ZAVE91] and the Jackson Development System (JSD) [ROLL91], represent the operational approach to software development. The operational approach incorporates three phases into the development process - modeling, specification and implementation. It closely resembles the automatic code development paradigm and when done iteratively also resembles the spiral method of development. The modeling though is not a mock-up or prototype of some part of a system. Rather it is a model of the relationships that will exist when the system \"operates.\" Thus they suffer from the same shortcomings as\nautomatic code generating systems. Namely, the difficult task of correctly specifying requirements still exists and the system produced will be limited to a relatively narrow problem domain such as a data intensive business application or database interactions. The operational approach to software development is not adequate for the prototyping of more general behavior.\n\n4. Megaprogramming Systems\n\nMegaprogramming is the attempt to develop systems from existing modules. Two examples are the Common Prototyping Language (CPL), a Defense Advanced Research Project Agency initiative that became Prototyping Technology (Prototech) [KIMB92] and the earlier Rapid Prototyping to Investigate End-user Requirements (RaPIER) [WELC86]. Megaprogramming is therefore a more sophisticated form of code reuse. As such, it can be an effective way to better explore a relatively well documented problem domain or one for which work is already underway. However, it is limited as a tool for probing new requirements though. It is problematic to write the code for the modules to be combined without first having a good understanding of the domain and the requirements of the proposed system.\n\n5. Prototyping Languages\n\nAs prototyping research gained momentum, it became clear to some that the ideal prototyping system would have at its core a language specifically developed for the task. Adapting existing languages invariably lead to shortcomings and compromises in the functionality of the prototyping system. PROTEUS [MILL90] and Durra [BARB91] were two attempts to develop a prototyping language. PROTEUS is intended for prototyping parallel and distributed environments. It contains set\ntheoretical notation with a small set of mechanisms for controlling parallel execution. It relies on a shared variable model of concurrency and focuses on regulating synchronization and communication. Durra is a task description language for developing distributed applications. It constructs a program by having the user specify the distributed application structure and the resources allocated to each component. The developer must still code each task and process but templates exist for creating the necessary interfaces.\n\nThe limitations on languages such as PROTEUS and Durra are that they are designed for relatively narrow domains and they cannot function without some sort of support system. There is no user interface, such as a graphical user interface (GUI), to aid developers. You cannot simply load them into your computer and start designing prototypes. So while the idea of developing languages specifically for prototyping is important for any viable prototyping system, it is still just one of several elements needed.\n\n6. Computer Aided Software Engineering (CASE) Tools\n\nThe natural result of all the research into different aspects of prototyping was the creation of CASE tools that combined many of the disparate areas of research into one synergistic mechanism for producing prototypes. CAPS and Proto [ACOS94] are two such systems. Where CAPS focuses on applications in the hard real time problem domain, Proto operates on distributed, parallel systems. Proto provides, as does CAPS, a design environment for the system analyst using the System Specification and Design Language (SSDL). The design environment includes execution support, a GUI and software reuse in order to make it a comprehensive, efficient tool for developing\nprototypes. This total integration of specialized prototyping language and tailored support environment is necessary to unlock the full potential that prototyping offers to software development.\n\nThere have been attempts to create prototyping systems without the overhead of creating the specialized, integrated system described above. They attempt to model prototypes using tools based on such things as Petri nets or relational databases. However, these tools are cumbersome and ultimately limited in their application.\n\n7. Prototyping Systems Summary\n\nThe above discussion of the history of prototyping systems is not comprehensive but simply representative of the different areas of research that have contributed to the considerable body of knowledge concerning software development with prototypes. As with any technology, software development is an ever-changing entity. Currently, the iterative approach of the spiral method of software development promises the best chance of creating software systems that actually satisfy the requirements specified by the user. The key to making it effective for anything except trivial systems is the ability to rapidly produce prototypes to examine proposed system behavior. Many of the research efforts involving prototyping have contributed to the field and then fallen into disuse as their productiveness reached practical limits. CAPS has weathered the turbulence that accompanies any emerging technology and today is not only alive but a vital, leading research tool in creating prototypes for supporting software system development.\nC. CAPS DEVELOPMENT\n\nAs the importance of prototyping to determining system behavior during development became clear, it also became obvious that to be effective prototypes would have to be created quickly. The requirement for a means to rapidly prototype leads to the seemingly obvious conclusion that a computer aided tool needed to be fabricated for this effort to succeed. At the time, the most successful systems for automatically generating code were focused in narrow problem domains and relied upon templates or generic solutions. In order to achieve the type of powerful, automated prototyping system envisioned, a computer language would have to be designed specifically for this purpose. That language was Prototype System Description Language (PSDL) [LUQI88b]. The objective of PSDL was to mechanically create documents that could be processed and executed at the specification level. In other words, PSDL was designed to be an executable prototyping language at the specification or design level.\n\nAs CAPS is built around PSDL, PSDL provides more than simply an executable prototyping language. Queries to search the database repository of reusable software components are based on PSDL. CAPS incorporates a GUI with which the system designer can graphically represent the desired requirements. CAPS will transform this graphical description into PSDL. Once in PSDL, the Ada components can be generated and bound together. After compilation, CAPS provides the facilities for graphically displaying the prototype. This allows system behavior to be evaluated and the necessary changes made to requirements in a timely manner. Thus, CAPS supports an iterative approach to software system development.\nD. PROTOTYPING RISKS\n\nIt would be unfair and unrealistic to think that prototyping does not incur some risks. It is certainly not the fabled silver bullet but simply a means for increasing the efficiency and accuracy of the system development process. It is important to understand the shortcomings of prototyping in order to take full advantage of its tremendous potential. Some of the risks associated with prototyping are:\n\n- overly enthusiastic developers who want to continually iterate and evolve a prototype by adding additional functionality beyond that which was originally being investigated;\n\n- classification of a prototyping effort as rapid can lead managers to think that this area can easily absorb budget cuts and shortcuts without affecting the product;\n\n- the temptation to substitute a prototype that appears to work for a fully documented and tested final product; and\n\n- a misunderstanding about the purpose of prototyping in the development process by users or customers can lead to acrimony with the development team and compromise the close working relationship that produces the best results.\n\nE. THE FUTURE\n\nCAPS today is an energetic, productive research effort into the use of rapid prototyping for software development. Its contributions are many and continue to appear at an impressive rate. Distributing CAPS itself certainly will ensure its lasting viability. Perhaps, however, even more is needed if CAPS is to remain at the leading edge of this research field and eventually become a mature product widely used throughout commercial software development. Focusing only on the domain of hard\nreal time applications is certainly becoming a limitation. The not too distant future, actually beginning to appear already, will see the emergence of applications that combine the requirements of hard real time constraints with concurrent operation across distributed networks that are growing seemingly without bound. Failure to support such applications risks being left on the sidelines or marginalized into some software development niche.\nIII. REQUIREMENTS ANALYSIS FOR DEPLOYING CAPS IN A DISTRIBUTED ENVIRONMENT\n\nFielding a sound, usable system doesn't occur by happenstance or even simply hard work. It is the result of a great deal of careful analysis and planning long before any implementation ever begins. If the requirements are not properly detailed, you can easily end up with a system that does something very well but does not do what the customer wanted. If the architecture is not precise, the development can spin out of control during implementation as each ambiguity results in a workaround. These workarounds and individual interpretations of what the designers meant compound on each other until system cohesion begins to suffer. The goal of this chapter is to fabricate the foundation of a clear and logical requirements analysis.\n\nA. CREATING A WELL DESIGNED SYSTEM\n\nThe goal of any system design should be the production of a system that is effective, efficient, robust and maintainable. Currently, the best way to achieve that goal is through rigorously applying the techniques of object-oriented analysis and design. Modeling is the underpinning that makes object-oriented analysis and design successful. Through modeling, everyone involved in the development process, from stakeholders to testers to managers, can come to a clear understanding and agreement about how the system will ultimately perform. Today, the state of the practice for modeling is the Unified Modeling Language (UML).\n\n1. UML Overview\n\nUML was designed to be as flexible as possible. In fact, it can be applied to almost any process, not just software design. It is meant to simply be a tool in the\nsoftware engineers toolkit. However, it can be a very powerful tool. Utilized to its fullest, UML can be integrated into a project from the outset while searching for the complete requirements and used through designing the architecture, implementing the desired system and finally testing the production code. It is a language that focuses on the conceptual and physical nature of a system. Thus it can be used to build the blueprints for a software system. Specifically, UML is designed for the visualizing, specifying, constructing and documenting of software artifacts [BOOC99].\n\na. **Visualizing**\n\nUML helps a system developer record and present to others the ideas he/she has. This can be a tremendously powerful way of fostering communication between the stakeholders, developers, project managers, users and any other interested party.\n\nb. **Specifying**\n\nUML capitalizes on the improved communications by allowing the developer, using his/her enhanced understanding of the system objectives, to build models that are precise, unambiguous and complete.\n\nc. **Constructing**\n\nThe developer can directly connect the models to various programming languages. Thus, it is possible to generate programming source code in languages such as Ada, C++ and Java.\nd. Documenting\n\nMany artifacts will be produced during a development cycle while using UML. These can form the basis of a thorough, persistent documentation effort.\n\n2. Using UML to Redesign CAPS\n\nAs stated before, UML is only a tool in the software design process. It is not a set-in-stone, explicitly detailed process. Rather, it is up to the developer to decide how to best employ UML. UML gives you the structural pieces for creating a solid design but there are many ways to actually put the pieces together. The nature of UML though lends itself to best supporting a spiral or incremental development approach.\n\nWe view this work as the beginning effort in redesigning CAPS for the future. Our goal is to first establish the requirements for an improved, distributed CAPS. The requirements are just a description of the needs and desires for what a system should do when deployed. Although this is a simple idea, it is critically important. If the requirements are not clearly and accurately defined, all that comes afterwards in the development process can be easily compromised. We have chosen to work with the UML model in this effort because we believe it can be easily extended in follow on theses.\n\nOur methodology in defining the requirements for the next CAPS will be to first determine the necessary system functions and attributes. Next, we will promote a better understanding of the processes involved with the application of use cases. Finally, we will complete the analysis with a proposed conceptual diagram. We strongly\nbelieve that this will be the key to a successful design and implementation phase in the future.\n\nB. METHODOLOGY SPECIFICS\n\nThe methodology we used for determining the requirements is detailed below.\n\n1. System Functions\n\nSimply stated, the system functions are what the system should actually do in the real world. System attributes, on the other hand, are non-functional system qualities. System functions can placed in one of two categories - evident or hidden. The user is aware when evident functions are being performed. The performance of hidden functions is not visible to the user. Often, underlying technical services, such as saving information to a persistent storage mechanism, are hidden.\n\nConstraints and details influence system attributes. These also fall into two categories - must and want. In reality, if a constraint is truly real, it should be classified as only must. Thus it is only attribute details that are characterized as must or want.\n\n2. Use Cases\n\nSimply put, use cases are a narrative description of domain processes that highlight the interactions between the system being designed and external agents. External agents can be such things as people, other systems, computers or processes. According to the creators of the UML, a use case is a description of a set of sequence actions that a system performs that yields an observable result to a particular actor. A use case is used to structure the behavioral things in a model. [BOOC99]\n\nCapturing the intended behavior of the system being designed is the goal of a use case. This facilitates easier, more complete communication end users, domain experts and developers. Use cases help draw attention to high risk areas sooner by\nfostering clearer investigations of domain processes. Any discussion of implementation should be avoided in use cases. The goal is to discuss what should be done, not how to do it. However, use cases can be utilized to corroborate about a proposed architecture. Two types of use case will be of interest in reengineering CAPS. First, high-level use cases will demonstrate all the interactions between actors and the system in very general terms. It provides a broad-brush overview of what the system should accomplish. The more interesting or critical use cases will be further detailed in expanded use cases. Finally, a use case diagram will link the narrative use cases to the UML.\n\nUse cases can help validate the rules of interactions between actors and actors or actors and the system. Exploration of the variations on scenarios can result from use case discussions. Often, nontrivial scenarios will have alternate paths of action revealed during such discussions and possibly one of them will be an improvement on the original idea. The crucial characteristic is work should always be accomplished. In other words, something should be done that’s of value to an actor.\n\nLastly, use cases can form the basis for developing test plans. As use cases are modified, the changes needed in the test plan are clearly established. A use case gives the test developer a straightforward, plain language narrative of what is supposed to happen. As use cases can be easily extended and more detailed throughout the development process, they make it possible to easily support a spiral or incremental development methodology.\n\n3. Conceptual Model\n\nThe conceptual model illustrates meaningful concepts, i.e., objects, in a problem domain. Decomposition by concepts supports object oriented analysis whereas\nstructural analysis is decomposition by processes or functions. Developing a comprehensive set of objects is the key to successful object oriented analysis. A static structures diagram expresses the conceptual model in UML. The concepts are identified and their attributes delineated as well as their associations with other concepts. There are no methods listed though. This construction serves to emphasize the fact that concepts in the conceptual model are representing real world entities and not software components. The concepts will be derived from the use cases and functional requirements.\n\nC. REQUIREMENTS ANALYSIS RESULTS\n\nThe results of the initial requirements analysis for reengineering CAPS are detailed below.\n\n1. Functional Requirements\n\nThe functional requirements for a reengineered CAPS are listed in Tables 3.1 - 3.7 grouped by various user inputs, system management, network support and project management.\n\nTable 3.1 User Input Functions-Requirements Analysis\n\n<table>\n<thead>\n<tr>\n<th>Ref #</th>\n<th>Function</th>\n<th>Function Category</th>\n<th>Attribute</th>\n<th>Details and Constraints</th>\n<th>Detail Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R1.1</td>\n<td>Record stakeholder comments</td>\n<td>evident</td>\n<td>interface metaphor</td>\n<td>form driven text format</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R1.2</td>\n<td>Record user comments</td>\n<td>evident</td>\n<td>interface metaphor</td>\n<td>form driven text format</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R1.3</td>\n<td>Record requirements for the system being developed</td>\n<td>evident</td>\n<td>interface metaphor</td>\n<td>form driven text format</td>\n<td>must</td>\n</tr>\n</tbody>\n</table>\n### Table 3.2 User Input Functions-System Modeling/Specification\n\n<table>\n<thead>\n<tr>\n<th>Ref #</th>\n<th>Function</th>\n<th>Function Category</th>\n<th>Attribute</th>\n<th>Details and Constraints</th>\n<th>Detail Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R1.4</td>\n<td>Model hard real time systems</td>\n<td>evident</td>\n<td>interface metaphor</td>\n<td>graphical user interface for flow diagram and form metaphor input for hard real time constraints</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R1.5</td>\n<td>Model distributed systems</td>\n<td>evident</td>\n<td>interface metaphor</td>\n<td>graphical user interface for flow diagram and form metaphor input for distributed system constraints</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R1.6</td>\n<td>Model concurrent systems</td>\n<td>evident</td>\n<td>interface metaphor</td>\n<td>graphical user interface for flow diagram and form metaphor input for concurrent system constraints</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R1.7</td>\n<td>Model any combination of hard real time, concurrent or distributed system</td>\n<td>evident</td>\n<td>interface metaphor</td>\n<td>graphical user interface for flow diagram and form metaphor input for hard real time, concurrent and/or distributed system constraints</td>\n<td>must</td>\n</tr>\n</tbody>\n</table>\n\n### Table 3.3 User Input Functions-Prototype Development\n\n<table>\n<thead>\n<tr>\n<th>Ref #</th>\n<th>Function</th>\n<th>Function Category</th>\n<th>Attribute</th>\n<th>Details and Constraints</th>\n<th>Detail Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R1.8</td>\n<td>Translate PSDL code into 3rd generation object oriented language source code</td>\n<td>evident</td>\n<td>response time</td>\n<td>source code will be generated in less than 2 minutes</td>\n<td>want</td>\n</tr>\n<tr>\n<td>R1.9</td>\n<td>Edit prototype source code</td>\n<td>evident</td>\n<td>response time</td>\n<td>source code will be available in less than 10 seconds</td>\n<td>want</td>\n</tr>\n<tr>\n<td>R1.10</td>\n<td>Compile software modules in a prototype</td>\n<td>evident</td>\n<td>response time</td>\n<td>object code will be generated in less than 2 minutes</td>\n<td>want</td>\n</tr>\n<tr>\n<td>R1.11</td>\n<td>Link compiled modules in a prototype</td>\n<td>evident</td>\n<td>response time</td>\n<td>linking will be completed in less than 2 minutes</td>\n<td>want</td>\n</tr>\n<tr>\n<td>R1.12</td>\n<td>Execute prototype</td>\n<td>evident</td>\n<td>platform</td>\n<td>prototype must be able to execute on UNIX and Windows95/98/NT</td>\n<td>must</td>\n</tr>\n</tbody>\n</table>\nTable 3.3 User Input Functions-Prototype Development (continued)\n\n<table>\n<thead>\n<tr>\n<th>Ref.</th>\n<th>Function</th>\n<th>Attribute</th>\n<th>Details and Constraints</th>\n<th>Detail Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R1.13</td>\n<td>Statically check hard real-time timing constraints for system prototype</td>\n<td>evident</td>\n<td>response time</td>\n<td>want</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>complete timing validation in less than 1 minute</td>\n<td></td>\n</tr>\n<tr>\n<td>R1.14</td>\n<td>Dynamically check hard real-time timing constraints for system prototype</td>\n<td>evident</td>\n<td>fault tolerance</td>\n<td>must</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>identify violations of timing constraints while executing</td>\n<td></td>\n</tr>\n<tr>\n<td>R1.15</td>\n<td>Dynamically report network collisions for distributed system prototype</td>\n<td>evident</td>\n<td>fault tolerance</td>\n<td>must</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>identify details of simulated network collisions while executing</td>\n<td></td>\n</tr>\n<tr>\n<td>R1.16</td>\n<td>Dynamically record synchronization details for system prototype</td>\n<td>evident</td>\n<td>fault tolerance</td>\n<td>must</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>identify details of simulated network timing while executing</td>\n<td></td>\n</tr>\n<tr>\n<td>R1.17</td>\n<td>Save component to local persistent storage</td>\n<td>hidden</td>\n<td>response time</td>\n<td>want</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>save should execute in less than 1 minute</td>\n<td></td>\n</tr>\n<tr>\n<td>R1.18</td>\n<td>Save project to local persistent storage</td>\n<td>hidden</td>\n<td>response time</td>\n<td>want</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>save should execute in less than 1 minute</td>\n<td></td>\n</tr>\n<tr>\n<td>R1.19</td>\n<td>Commit component to persistent storage</td>\n<td>hidden</td>\n<td>response time</td>\n<td>want</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>commit should execute in less than 1 minute</td>\n<td></td>\n</tr>\n<tr>\n<td>R1.20</td>\n<td>Commit project to persistent storage</td>\n<td>hidden</td>\n<td>response time</td>\n<td>want</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>commit should execute in less than 1 minute</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nTable 3.4 User Input Functions-Reuse\n\n<table>\n<thead>\n<tr>\n<th>Ref #</th>\n<th>Function</th>\n<th>Function Category</th>\n<th>Attribute</th>\n<th>Details and Constraints</th>\n<th>Detail Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R1.21</td>\n<td>Select software module from reuse database</td>\n<td>evident</td>\n<td>shared component access</td>\n<td>provide matches in less than 1 minutes</td>\n<td>want</td>\n</tr>\n<tr>\n<td>R1.22</td>\n<td>Save software modules to reuse database</td>\n<td>hidden</td>\n<td>shared component access</td>\n<td>provide Software Librarian controls for reuse database</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R1.23</td>\n<td>Delete software modules from reuse database</td>\n<td>hidden</td>\n<td>shared component access</td>\n<td>provide Software Librarian controls for reuse database</td>\n<td>must</td>\n</tr>\n</tbody>\n</table>\n### Table 3.5 System Administration\n\n<table>\n<thead>\n<tr>\n<th>Ref #</th>\n<th>Function</th>\n<th>Function Category</th>\n<th>Attribute</th>\n<th>Details and Constraints</th>\n<th>Detail Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R2.1</td>\n<td>Allow Software Librarian to add new users to access list for software component database</td>\n<td>hidden</td>\n<td>scalability</td>\n<td>allow enough users to support very large system development</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R2.2</td>\n<td>Allow Software Librarian to delete new users from access list for software component database</td>\n<td>hidden</td>\n<td>scalability</td>\n<td>allow enough users to support very large system development</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R2.3</td>\n<td>Allow project manager to grant file access to specific users</td>\n<td>hidden</td>\n<td>security</td>\n<td>only allow authorized user to access a project</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R2.4</td>\n<td>Allow project manager to revoke file access to specific users</td>\n<td>hidden</td>\n<td>security</td>\n<td>only allow authorized user to access a project</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R2.5</td>\n<td>Recover from a local system failure</td>\n<td>hidden</td>\n<td>fault tolerance</td>\n<td>Restore system back to a safe state after a local failure</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R2.6</td>\n<td>Recover from a global application failure</td>\n<td>hidden</td>\n<td>fault tolerance</td>\n<td>Restore system back to a safe state after system wide application failure</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R2.7</td>\n<td>Recover from a local application failure</td>\n<td>hidden</td>\n<td>fault tolerance</td>\n<td>Restore system back to a safe state after a local application failure</td>\n<td>must</td>\n</tr>\n</tbody>\n</table>\n\n### Table 3.6 Network Support\n\n<table>\n<thead>\n<tr>\n<th>Ref #</th>\n<th>Function</th>\n<th>Function Category</th>\n<th>Attribute</th>\n<th>Details and Constraints</th>\n<th>Detail Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R3.1</td>\n<td>Transmit module to a remote site</td>\n<td>hidden</td>\n<td>shared component access</td>\n<td>securely get work from one site to another site</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R3.2</td>\n<td>Download module from a remote site</td>\n<td>hidden</td>\n<td>shared component access</td>\n<td>securely get work from one site to another site</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R3.3</td>\n<td>Detect errors in transmission of modules</td>\n<td>hidden</td>\n<td>fault tolerance</td>\n<td>ensure integrity of modules moving over network</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R3.4</td>\n<td>Generate alert for detected errors in transmission</td>\n<td>hidden</td>\n<td>fault tolerance</td>\n<td>ensure integrity of modules moving over network</td>\n<td>must</td>\n</tr>\n</tbody>\n</table>\n### Table 3.6 Network Support (continued)\n\n<table>\n<thead>\n<tr>\n<th>Ref #</th>\n<th>Function</th>\n<th>Function Category</th>\n<th>Attribute</th>\n<th>Details and Constraints</th>\n<th>Detail Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R3.5</td>\n<td>Recover from a global system failure</td>\n<td>hidden</td>\n<td>fault tolerance</td>\n<td>Restore system back to a safe state after system wide failure</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R3.6</td>\n<td>Acknowledge error-free transmission of module</td>\n<td>Hidden</td>\n<td>fault tolerance</td>\n<td>ensure integrity of modules moving over network</td>\n<td>must</td>\n</tr>\n</tbody>\n</table>\n\n### Table 3.7 Project Management\n\n<table>\n<thead>\n<tr>\n<th>Ref #</th>\n<th>Function</th>\n<th>Function Category</th>\n<th>Attribute</th>\n<th>Details and Constraints</th>\n<th>Detail Category</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R4.1</td>\n<td>User must log in securely in order to use system</td>\n<td>evident</td>\n<td>response time</td>\n<td>less than 10 seconds</td>\n<td>want</td>\n</tr>\n<tr>\n<td>R4.2</td>\n<td>Create new project</td>\n<td>evident</td>\n<td>response time</td>\n<td>less than 5 seconds</td>\n<td>want</td>\n</tr>\n<tr>\n<td>R4.3</td>\n<td>Load existing project</td>\n<td>evident</td>\n<td>response time</td>\n<td>less than 10 seconds</td>\n<td>want</td>\n</tr>\n<tr>\n<td>R4.4</td>\n<td>Record version for all software artifacts</td>\n<td>hidden</td>\n<td>ease of use</td>\n<td>system must track and record order in which artifacts entered</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R4.5</td>\n<td>Add component to project</td>\n<td>evident</td>\n<td>response time</td>\n<td>component should included in project in less than 1 minute</td>\n<td>want</td>\n</tr>\n<tr>\n<td>R4.6</td>\n<td>Merge components from different sources into one component</td>\n<td>evident</td>\n<td>ease of use</td>\n<td>system must automatically merge components, tracking versions</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R4.7</td>\n<td>Merge components from different sources into one project</td>\n<td>evident</td>\n<td>ease of use</td>\n<td>system must automatically merge components, tracking versions</td>\n<td>must</td>\n</tr>\n<tr>\n<td>R4.8</td>\n<td>Alert project manager to conflicts during merge operations</td>\n<td>evident</td>\n<td>version control</td>\n<td>system must identify version conflicts and inform the project manager</td>\n<td>must</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td>response time</td>\n<td>Project manager should be alerted in less than 2 minutes</td>\n<td>want</td>\n</tr>\n</tbody>\n</table>\n2. High-level Use Cases\n\nThe high-level use case are detailed below.\n\nUse Case: U1. Start-up\nActors: System Administrator\nType: primary\nOverview: System Administrator logs onto host system and initiates CAPS.\nCross Reference: Functions: R2.5, R2.6, R2.7, R3.5\n\nUse Case: U2. Log in\nActors: User\nType: primary\nOverview: After CAPS is initiated, a user must log into CAPS in order to determine what project and reuse database privileges the user owns.\nCross Reference: Functions: R2.3, R4.1\n\nUse Case: U3. Open project\nActors: User\nType: primary\nOverview: After logging into CAPS, user can either open a new project or select an existing project and open it, if he has the proper authorization from the project manager.\nCross Reference: Functions: R2.3, R4.2, R4.3\nUse Case: U4. Modify prototype\n\nActors: User\n\nType: primary\n\nOverview: After opening a project, the user will be able to make changes to the graphical interface of the control flow diagram or to the text boxes associated with either objects or data streams in the diagram. These changes will be automatically reflected in the PSDL code. The user can record user comments, stakeholder comments and requirements for the system being prototyped. Additionally, the user can directly access the PSDL code and change it manually.\n\nCross Reference: Functions: R1.1, R1.2, R1.3, R1.4, R1.5, R1.6, R1.7, R1.21, R4.4, R4.5\n\nUse Case: U5. Retrieve component from reuse database\n\nActors: User\n\nType: primary\n\nOverview: The user accesses the reuse database and inputs search parameters. CAPS responds with no match, unique match or a list of possible matches. CAPS generates an alert if there is an error in transmission and an acknowledgement if the transfer is successful.\n\nCross Reference: Functions: R1.21, R3.2, R3.4, R3.6\nUse Case: U6. Save\nActors: User\nType: primary\nOverview: User has opened a project or component and now saves it to local persistent storage.\nCross Reference: Functions: R1.17, R1.18\n\nUse Case: U7. Modify GUI for displaying prototype execution\nActors: User\nType: primary\nOverview: User selects and then edits the files that provide functionality for displaying prototype execution.\nCross Reference: Functions: R1.4, R1.5, R1.6, R1.7, R1.8, R1.9\n\nUse Case: U8. Generate executable prototype\nActors: User\nType: primary\nOverview: The user translates the prototype in order to create source code in an implementation language from the PSDL and link it. The user will then verify through CAPS that all static hard real time constraints are met. The user will then compile the prototype source code.\nCross Reference: Functions: R1.9, R1.10, R1.11\nUse Case: U9. Execute the prototype\n\nActors: User\n\nType: primary\n\nOverview: The user will execute the prototype. As the user test the prototype functionality, CAPS will verify that all dynamic hard real time, concurrency and network constraints are met. CAPS will allow the user to record stakeholder and/or user comments.\n\nCross Reference: Functions: R1.1, R1.2, R1.3, R1.12, R1.13, R1.14, R1.15, R1.16\n\nUse Case: U10. Manage project changes\n\nActors: User, Project Manager\n\nType: primary\n\nOverview: User (possibly more than one) will submit module(s) to the Project Manager for incorporation into the project prototype. The user may elect to return the entire prototype after making changes to only some of the modules. In this case the Project Manager must identify which modules are changed or new. If the module does not already exist in the project database, the Project Manager will merge the submitted module(s) into one module, resolving any conflicts. CAPS will assign and track a version number and insert the module into the project database, making ties to all other modules that may exist in the project database. If the module\npreviously existed in the project database, the Project Manager will merge all submitted modules with the existing one, resolving any conflicts. CAPS will update the version number. If an existing module is submitted to the Project Manager, CAPS will verify that all other modules that it depends on are the most up to date version. CAPS will generate an alert if there is an error in transmitting a module and an acknowledgement if there is no error.\n\nCross Reference: Functions: R1.19, R1.20, R3.1, R3.3, R3.4, R3.6, R4.3, R4.4, R4.6, R4.7, R4.8\n\nUse Case: U11. Manage reuse database changes\n\nActors: User, Software Librarian\n\nType: primary\n\nOverview: User submits a new module, or an existing one that was modified, to the Software Librarian. When the Software Librarian accepts the module for inclusion in the reuse database, a version control number is assigned or updated as necessary and the module is saved to the reuse library. If the module was an update of an existing one, all users of the old version are alerted. The Software Librarian can also delete modules.\n\nCross Reference: Functions: R1.22, R1.23, R3.1, R3.3, R3.4, R3.6\nUse Case: U12. Add user to project access\nActors: Project Manager\nType: secondary\nOverview: The Project Manager grants a user access to a specific project.\nCross Reference: Functions: R2.3\n\nUse Case: U13. Delete user from project access\nActors: Project Manager\nType: secondary\nOverview: The Project Manager deletes a user’s access to a specific project.\nCross Reference: Functions: R2.4\n\nUse Case: U14. Add user to the reuse database\nActors: Software Librarian\nType: secondary\nOverview: Upon receiving request, Software Librarian will add user to the reuse database access list.\nCross Reference: Functions: R2.1\n\nUse Case: U15. Delete user from the reuse database\nActors: Software Librarian\nType: secondary\nOverview: Upon receiving request, Software Librarian will delete user from the reuse database access list.\n\nCross Reference: Functions: R2.2\n\nUse Case: U16. Exit project\nActors: User\nType: primary\nOverview: The user exits the current project. If unsaved data exist, CAPS will ask the user if they want to save the data before exiting the project.\n\nCross Reference: Functions: R1.18, R1.20\n\nUse Case: U17. Log off\nActors: User\nType: primary\nOverview: User request to log off from the current session of CAPS. If unsaved data exist, CAPS will ask the user if they want to save the data before logging the user off CAPS and quitting the current session of CAPS.\n\nCross Reference: Functions: R1.18, R1.20\n\n3. Expanded Uses Cases\n\nThe expanded use cases are detailed in Appendix A. They are: U3. Open project; U4. Modify prototype; U5. Retrieve component from reuse database; U7. Modify GUI for displaying prototype execution; U8. Generate executable prototype;\nU9. Execute the prototype; U10. Manage project changes; U11. Manage reuse database changes.\n\n4. Conceptual Diagrams\n\nThe list of components used in the conceptual diagrams is shown below in Table 3.8 and the detailed subsections are shown in figures 3.1 through 3.5. The complete descriptions of the relations and concepts are included in the detailed views.\n\n<table>\n<thead>\n<tr>\n<th>Table 3.8 Conceptual Diagram Components</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Access List</td>\n</tr>\n<tr>\n<td>Alert</td>\n</tr>\n<tr>\n<td>CAPS</td>\n</tr>\n<tr>\n<td>CAPS Graphical Interface</td>\n</tr>\n<tr>\n<td>CAPS Menu</td>\n</tr>\n<tr>\n<td>Comment</td>\n</tr>\n<tr>\n<td>Compiler</td>\n</tr>\n<tr>\n<td>Component</td>\n</tr>\n<tr>\n<td>Constraint</td>\n</tr>\n<tr>\n<td>Editor</td>\n</tr>\n<tr>\n<td>Error</td>\n</tr>\n<tr>\n<td>Executable Code</td>\n</tr>\n<tr>\n<td>GUI Builder</td>\n</tr>\n<tr>\n<td>Host System</td>\n</tr>\n<tr>\n<td>List of Possible Matches</td>\n</tr>\n<tr>\n<td>Network</td>\n</tr>\n<tr>\n<td>Persistent Storage</td>\n</tr>\n<tr>\n<td>Project</td>\n</tr>\n<tr>\n<td>Project Database</td>\n</tr>\n<tr>\n<td>Project Manager</td>\n</tr>\n<tr>\n<td>Prototype</td>\n</tr>\n<tr>\n<td>Prototype GUI</td>\n</tr>\n<tr>\n<td>PSDL Code</td>\n</tr>\n<tr>\n<td>PSDL Data Stream</td>\n</tr>\n<tr>\n<td>PSDL Diagram</td>\n</tr>\n<tr>\n<td>PSDL Object</td>\n</tr>\n<tr>\n<td>Query</td>\n</tr>\n<tr>\n<td>Remote Site</td>\n</tr>\n<tr>\n<td>Requirement</td>\n</tr>\n<tr>\n<td>Component</td>\n</tr>\n<tr>\n<td>----------------------------</td>\n</tr>\n<tr>\n<td>Reuse Library</td>\n</tr>\n<tr>\n<td>Reuse Library Search</td>\n</tr>\n<tr>\n<td>Scheduler</td>\n</tr>\n<tr>\n<td>Search Parameters</td>\n</tr>\n<tr>\n<td>Software Librarian</td>\n</tr>\n<tr>\n<td>Source Code</td>\n</tr>\n<tr>\n<td>Stakeholder</td>\n</tr>\n<tr>\n<td>System being Designed</td>\n</tr>\n<tr>\n<td>System Parameters</td>\n</tr>\n<tr>\n<td>Text Box</td>\n</tr>\n<tr>\n<td>Translator</td>\n</tr>\n<tr>\n<td>User</td>\n</tr>\n<tr>\n<td>Work Station</td>\n</tr>\n</tbody>\n</table>\nFigure 3.1 Conceptual Diagram - Network Support\nFigure 3.2 Conceptual Diagram - Reuse Support\nFigure 3.3 Conceptual Diagram - Management Support\nFigure 3.4 Conceptual Diagram - Execution\nFigure 3.5 Conceptual Diagram - User Inputs\nIV. ARCHITECTURAL DESIGN FOR CAPS IN A DISTRIBUTED NETWORK\n\nThe choices for how to design the architecture for a distributed CAPS fall along an unbroken continuum. At one end you have dumb client machines and a super smart server that does all the work and returns the results to the clients for display to the user. On the other end of the spectrum you have a set up that resembles most Local Area Networks (LAN) where the server simply provides a service, such as file downloads, and the client machines do all the work. The first is highly centralized and the second highly decentralized. We believe that the most optimum solution is a client-server architecture that falls in-between the extremes of this continuum. The rapid growth in the amount of bandwidth available on all kinds of networks, including the Internet, make sophisticated client-server architectures very feasible.\n\nA. DEFINING THE CAPS CLIENT-SERVER ARCHITECTURE\n\nAny design must take advantage of the increasing power of today's desktop personal computers (PC). By moving a significant load from the server to the client machines, you can dramatically improve scalability by reducing the amount of work the server must do and the quantity of data it must send to client machines. However, the implementation of this client-server architecture should not be limited to just one type of PC. Indeed, client machines do not necessarily have to even be a PC. They could, for instance, be a UNIX workstation. This diversity reflects the reality of most networks today. They are becoming more and more heterogeneous. The internet is the ultimate example of this heterogeneity but by no means the only example. The Heterogeneous Systems Integrator (HSI), which contains a PSDL graphical editor, written by Ilker Duranlioglu [DURA99] provides an important first step in creating a powerful CAPS\nclient that any truly successful distributed CAPS design will require. The HSI is an all Java implementation.\n\n1. A Three Tier Client-Server Design\n\nA robust three tier design is the preferred way to implement a distributed CAPS in the client-server model. The three tier design offers several advantages over the older two tier model. First, it more closely resembles the object oriented paradigm practiced today. You can encapsulate the functionality of the client-server design easily in a three tiered model and as long as the interfaces between each tier remain unchanged, you can update the separate parts independently. The three tiers in a distributed CAPS are the client side, represented by the HSI, the communication server that communicates with multiple clients over a network and the 'back end' programs that do the actual work requested by the clients on the computational server. Additionally, by carefully allocating responsibilities in the design you can noticeably improve performance and latency by ensuring good load balancing. Thus, no particular node becomes a bottleneck.\n\n2. Component Responsibilities\n\nOne of the first questions to resolve in designing a distributed system, is who will be responsible for maintaining state information. This can be quite complicated and introduce large inefficiencies if it is done at one central location, i.e., on the server side of the network. Thus, we decided that the best approach was for each client to maintain their own state information. Fortunately, this does not introduce very much additional complexity to the HSI already written. The HSI already manages threads that are created by opening prototypes and editors. It is a relatively simple matter for the HSI to include state information whenever it invokes services from the server. This allows the\nserver to focus on facilitating requests from various clients. If the server asynchronously passes client requests off to ‘back end’ for processing, then it can continue to efficiently service clients. While the local clients manage their own states, one centrally located repository greatly simplifies configuration management and version control. Local clients can open prototypes from either local memory or from the server side. They can also save to either location. However, the project manager controls centrally what changes get into the master copy of a prototype. Thus when various clients submit changes to a prototype, they are saved into the user’s centrally located folder and the project manager decides when and how to access them. This arrangement allows the project manager to easily maintain control over the merging process and the resulting configuration and versioning decisions. Users can only read the master prototype, and only when the project manager permits it.\n\nB. IMPLEMENTING THE CAPS CLIENT-SERVER ARCHITECTURE\n\nThere are many ways in which a distributed CAPS could be implemented. The first decision is what language, or languages, to use. The original CAPS is written largely in Ada, C and C++. Given the realities of writing distributed applications, among other considerations, we decided that Java would be a superior language with which to implement a distributed CAPS. Choosing an implementation language is only part of the total implementation decision. The other part is determining how the communications will actually take place in a distributed system. For this, we decided that the Object Management Group’s (OMG) Common Object Request Broker Architecture (CORBA) offered the best possible solution. Our reasons for these selections are detailed below.\n1. The Selection of Java\n\nThere are many reasons why Java is the language of choice when implementing a distributed application. First, the ease of migrating Java across different machines and operating systems is an enormous advantage. As discussed previously, it almost a certainty that any distributed system deployed will by necessity be heterogeneous. Every major type of computer and operating system today has a Java Virtual Machine (JVM) written for it. This allows Java byte code written on one type of machine to execute on any machine that has a JVM. This was shown to work while implementing our proof of concept demonstration. Byte code that was created in a Windows NT PC environment was copied to a Sun Solaris Unix machine and successfully executed without any alterations. This type of portability will greatly simplify implementing a distributed CAPS. Secondly, Java was created as language to operate on the Internet and World Wide Web (WWW). Thus it possesses many built-in capabilities that facilitate network operations. Additionally, Java has facilities for things such as multi-threading, garbage collection and error management designed into the language that appreciably reduce the difficulty of designing an application. Lastly, as will be discussed, Java is a natural fit with CORBA and the two are quickly merging in the world of network applications.\n\n2. The Selection of CORBA\n\nCORBA provides many advantages over other competing middleware solutions. A review of CORBA will facilitate a discussion of these advantages.\na. **CORBA Description**\n\nAs previously discussed, it is assumed that a distributed CAPS must perform in a heterogeneous environment. While heterogeneity in itself is not negative and may, in fact, be viewed as an asset to be leveraged, it does present challenges to us as software developers desiring to implement an application in a heterogeneous networked system. Heterogeneity creates the need for middleware that can enable the sharing of objects, functions and types without causing extensive software re-work for developers, or complex work-arounds for users.\n\nThe Object Management Group (OMG) was formed in 1989 to develop, adopt, and promote standards for the development and deployment of applications in distributed heterogeneous environments. Since that time, the OMG has grown to be the largest software consortium in the world, and has developed the Object Management Architecture (OMA). The OMA consists of an Object Model and a Reference Model. The Object Model defines how objects can be described, and the Reference Model, shown in Figure 4.1, deals with interactions between those objects. In the Object Model, clients issue requests for services to objects (much like a remote procedure call (RPC)). The implementations of these objects are hidden from the client. A key component of the Reference Model is the Object Request Broker (ORB), which facilitates communication between clients and objects. CORBA is the specification developed by the OMG that details the interfaces and characteristics of the ORB. In CORBA the terms “client” and “server” are not rigidly defined roles. The CAPS server could handle the request from client machines and in turn become a client itself when it invokes requests on some 'back end' implementation.\nIn CORBA, an application consists of one or more objects that may reside on the same or different platforms. An object provides service(s) that can be \"requested\" by a client. Clients obtain services from an object by making \"requests\" that consist of an operation, the name of the object that will respond, zero or more parameters, and an optional request context. The object may or may not return results to a client, and will return an exception if an abnormal condition occurs. Object implementations may be written in a variety of languages and may exist in a variety of forms. Essentially, CORBA allows components to discover each other and interoperate on an object bus. However, CORBA does much more than just create a simple object bus, as shown in Figure 4.2. It also provides an extensive set of services for such things as creating and deleting objects, accessing them by name, putting them in persistent storage, externalizing their states and forming ad hoc relationships between objects. Thus you can design an ordinary object and then give it the specific\ncharacteristics needed for a distributed application by using CORBA's multiple inheritance. [ORFA98]\n\nFigure 4.2 CORBA ORB Architecture From [SCHM99]\n\nMethods can be invoked statically or dynamically. In Static Invocation, a client's request is made via interface definition language (IDL) \"stubs\" on the client side, and the response is handled by IDL \"skeletons\" on the object side. The stubs and skeletons interface with the CORBA ORB. In Static Invocation, the IDL Client Stub converts data from the client's local data representation (type) to the Common Data Representation (CDR), which is platform and language independent. On the object's platform, the Object Skeleton executes the reverse operation. In Dynamic Invocation, requests are made via Dynamic Invocation Interface. With Dynamic Invocation the developer is afforded more flexibility. In Dynamic Invocation, the Dynamic Skeleton\nInterface (DSI) may take the place of the Static Invocation Object Skeleton to accomplish data conversion at run time.\n\nCORBA supports two types of (method) invocation semantics: synchronous invocation and asynchronous invocation. Synchronous invocation is blocking. The client will invoke the method and block until it receives a response from the server (object implementation). Asynchronous invocation is non-blocking. The client will invoke a method, continue its computation, and collect results as they arrive. With non-blocking primitives, the SEND primitive returns control to the requesting program as soon as the message is copied from the user buffer to the kernel buffer. The corresponding object that executes the RECEIVE primitive signals its intention to receive a message, provides a buffer into which the message will be copied and continues to execute. [POPE98]\n\nThrough the IDL stubs, a client can use RPC-style semantics (synchronous), or by using Dynamic Invocation Interface (DII) a client can use SEND/RECEIVE semantics. Using DII allows a client to directly access the underlying request mechanisms provided by the ORB. Applications use DII to dynamically issue requests to objects without requiring IDL stubs to be linked in. The DII allows clients to make non-blocking “deferred synchronous” (separate SEND and RECEIVE operations) and one way (SEND only) calls. [POPE98]\n\nMany industry leaders, including IBM, Novell, Borland/Visigenic, SunSoft, Netscape, Oracle and JavaSoft just to name a few, have recognized the importance of CORBA middleware in realizing the potential of heterogeneous, distributed systems[ORFA98]. In fact, CORBA is now part of the Defense Information\nInfrastructure Common Operating Environment (DII COE) standard web browser, and is finding increasing use in Department of Defense applications. The utility of CORBA lies in its ability to integrate diverse applications across a variety of networks and network protocols. CORBA’s language independent IDL’s allow objects to be used from a variety of programming languages, including COBOL, C, C++, Ada, Smalltalk, Perl and Java. CORBA-based applications are independent of network protocols so they may be run in a distributed system over a diverse network. These attributes ensure CORBA’s tremendous usefulness in a heterogeneous environment.\n\nb. **CORBA Advantages for a Distributed CAPS**\n\nCORBA certainly is not the only solution for implementing an application in a distributed environment. The other prominent options include legacy solutions that predate the ORB concept such as Java sockets, Common Gateway Interface (CGI) scripts with Hypertext Transfer Protocol (HTTP) and Java Servlets. Non-CORBA ORBs are JavaSoft’s Remote Method Invocations (RMI) and Microsoft’s Distributed Component Object Model (DCOM). As for simple performance metrics, the fastest implementation for operating over a network is a socket using a buffered data stream. However, as we’ll discuss below, this is not a realistic choice for implementing a distributed CAPS. The three ORBs, CORBA, DCOM and RMI, are very close in performance and as a group are a little less than twice as slow as a socket. Servlets are well over an order of magnitude slower than a socket and the CGI/HTTP combination is well over two orders of magnitude slower. [ORFA98]\n\nThe three legacy solutions all suffer from the fact that they operate at very low levels of abstractions. Sockets in particular are a relatively primitive model.\nSockets are 'close to the wire' in the sense that they are the lowest level of abstraction available. This accounts for their efficient performance but it also makes them difficult to program. The other solutions build upon sockets as a transport mechanism while shielding users from having to deal with the details of socket programming. CGI scripts over HTTP is the current predominant model for three tiered applications over the internet. HTTP provides simpler semantics on top of sockets which CGI scripts use to communicate between clients, servers and 'back end' resources. However, besides being incredibly slow, other disadvantages include a lack of typed parameter support and object reference persistence, a relatively low level of abstraction and poor scalability. A Servlet is a small piece of Java code loaded onto a server. It operates much as CGI but it overcomes some of the worst performance degradations by remaining in memory between request and by staying connected to 'back end' resources. As with CGI though, the lack of typed interfaces result in a proliferation of interfaces as the number of methods grows and each method must be prepared to marshal and unmarshal multiple data types.\n\nRMI and DCOM share many of the advantages of CORBA for developing distributed applications. There are however, some significant drawbacks to both. RMI and DCOM both lack the comprehensive services and facilities that are available for CORBA. These include a Naming Service, Event Service, Property Service, Relationship Service, Lifecycle Service, Security Service and a continually growing host of CORBA facilities such as mobile agents, data interchange, workflow, firewalls and business object frameworks. The ultimate goal of CORBA facilities is to provide an IDL interface for virtually every networked service. RMI is an all Java implementation, which\ncould potentially become a problem at some point in the future. It is also proprietary and thus doesn't interact with other ORBs. The extremely proprietary nature of DCOM is certainly its biggest disadvantage. Microsoft only produces Window versions of DCOM and in addition, it must run in their JVM. There are some third party attempts at porting it to other platforms, but so far these have met with limited success. Even if successfully ported, there exist deficiencies in the design of DCOM which make it inferior to CORBA. It does not follow the object oriented model since it precludes inheritance. There are work-arounds but they can be cumbersome. Also, object references are not persistent and due to the limitations of working only on Window platforms, it is not scalable.\n\nIn light of the discussion, it becomes clear that CORBA addresses many of the issues we initially identified as pertinent to developing a distributed CAPS. With CORBA, the type of network becomes irrelevant to the operation of a distributed CAPS. Indeed, the proof of concept implementation done for this work started on a single PC and then migrated seamlessly to first an all PC environment and then to one where the client resided on a PC and the server on a Sun Solaris Unix. The next step, to operate over the internet, would be just as smooth a transition. Clearly, the heterogeneous nature of any large network becomes immaterial given the fact that every important language has an IDL mapping and every major type of operating system supports CORBA. The fact that no special hardware is required is also a plus. CORBA's extensive support for exceptions and the ability to implement user defined exceptions provide for greatly improve fault tolerance. Despite the intuitive feeling that the overhead of CORBA must be significant, it is actually shown to be quite acceptable.\nWith the introduction of real-time CORBA this year, latency should become even less of an issue. Lastly, the CORBA services and facilities provide extensive support for current and future growth.\nV. A DISTRIBUTED CAPS PROOF OF CONCEPT IMPLEMENTATION\n\nThe primary objective in the initial implementation was to demonstrate the efficacy of a distributed CAPS design using Java and CORBA. The first step in this process was completed with the HSI which was written in Java and included a PSDL editor. There was, however, little other functionality built into the initial HSI. Our goal was to create an implementation where the HSI would run on a PC and remotely invoke methods on a CAPS server located on a Sun Solaris Unix machine. The mechanism for these invocations would be CORBA. Since this was a proof of concept implementation, only selected functionality was demonstrated in order to prove the effectiveness of the Java/CORBA combination before attempting large scale development.\n\nA. PRODUCT CHOICES FOR IMPLEMENTATION\n\nThere are many possible environments for developing Java code and currently there are three major suppliers of CORBA/Java ORBs. In selecting an environment for developing Java code, the continuum runs from using the Java Developer Kit (JDK) supplied by JavaSoft and a text editor which are a very minimalist approach to full feature, comprehensive integrated development environments (IDE). Java IDEs are offered by a host of vendors. We decided to use the newest version of the JavaSoft JDK, 1.2.2. There were several reasons for this. First, the JDK is supplied free of charge. Secondly, in keeping with the walk before running philosophy, choosing the JDK gave us a simpler, more straightforward design environment. It allowed us to concentrate on creating a distributed CAPS without the distraction of all the bells and whistles that accompany the more feature laden IDEs. The documentation with the JDK\nis also very comprehensive. As will be discussed below, the JDK has one additional advantage – a built-in Java ORB that is fully CORBA compliant.\n\nThe three Java ORBs available today are JavaSoft's JAVA IDL, Iona's OrbixWeb 3.0 and Borland/Visigenic's VisiBroker for Java 3.1. Much of the same reasoning for selecting JavaSoft's JDK for writing the Java code went into the selection of using JavaSoft's Java IDL for the ORB in our implementation. While far from a full feature ORB (it lacks such things as a non-volatile Naming Service and many of the add-on services) it is fully CORBA compliant. In our case, the simpler ORB was more a benefit than a disadvantage. As a distributed CAPS moves from the research stage to a production release, the work done can be easily migrated to a more full feature ORB. Also, it is very likely that JavaSoft will continue to improve the Java IDL and such a migration may not even be necessary. Java IDL is already built into the JDK environment. We did discover that some bugs exist in versions of JDK before 1.2.2 which prevented the Java IDL from operating properly. The IDL to Java compiler worked correctly but using a version earlier than 1.2.2 resulted in exceptions when attempting to connect to the ORB.\n\nB. IMPLEMENTATION DECISIONS\n\nThe HSI, as implemented by [DURA99], provided the GUI by which a user could create a prototype with the graphical editor and generate the corresponding PSDL code. It could open from and save to a local memory location or the user's allocated memory storage location on a network. The entire process was one controlled by the current instantiation of the HSI created by the user. In order to demonstrate the viability of a distributed CAPS operating in a client-server paradigm, we had to separate out some of\nthe functionality into distinct client and server processes. Additionally, we wanted to\nincorporate some of the tasks from the original stand-alone CAPS into our client-server\ndesigned one. The IDL file and the two files that implement the server are listed in\nAppendix B. The files generated by the IDL-to-Java compiler are listed in Appendix C.\nThe HSI files that were modified to implement the remote calls to the server are listed in\nAppendix D. All three appendixes include both source files and the corresponding\nJavadoc generated documentation.\n\nFirst, we decided that the user should be able to open an existing prototype from\neither the local memory or from prototypes stored on the server side of the network.\nThe user was also given the ability to save files on the server side as well as in his/her\nown memory space as before. This remote save was implemented as the commit\nfunction of the HSI. We decided to incorporate execution of the translate function on\nthe server side in order to further extend the work began in [DURA99]. When a user\nselects the translate function during a HSI session, the current prototype file is\ntransferred to the server where the translate is actually invoked. The Ada files\ngenerated are stored on the server in the user's directory and a message notifying the\nuser of a successful translate is sent to the HSI. Likewise, the user is notified after a\nprototype's PSDL file is successfully saved to the server side when the user invokes the\ncommit function from the HSI. On the server side, when the translate function is\ninvoked, a shell script is called which performs the actual translating. This is not a true\nthree tier design but as the primary objective was to test the communication between\nthe HSI and a remotely located server, it was acceptable. As this research matures, it\nmay be that ultimately the server communicates with the 'back end' implementation\ndoing the actual work over a second CORBA object bus. In essence, the server would become the client in a client-server relationship with the 'back end' implementation.\n\nThe interfaces of the methods needed to implement this initial design were described in CORBA IDL and compiled using the IDL-to-Java compiler in JDK 1.2.2. When invoking the IDL-to-Java compiler, the command line argument –fno-cpp is used in order to disable the C++ preprocessor that is defaulted enabled. This preprocessing is not needed and prevented the IDL-to-Java from performing properly in the lab. The result were 15 .Java files which represented all the classes required to implement the interfaces described in the initial IDL description. The corresponding .class files were created by the JDK 1.2.2 Java compiler. The files were responsible for the actual operation of the CORBA object bus by marshalling and unmarshalling data being passed over the network between the client HSI and the server side. Additionally, they provide stub and skeleton implementations containing all the necessary information for proper communications with the ORB. They simply had to be extended and the desired functionality added, e.g. saving or translating a file, and they were ready to be compiled into .class files by the Java compiler.\n\nSince this was a proof of concept demonstration, robustness, ease of use and efficiency were not primary considerations. Minimal error checking, such as ensuring that a prototype was opened in the HSI before invoking the translate function on the server, was incorporated. However, other than the built in mechanisms such as type checking, not much work was done in this area. Given the effectiveness of Java exceptions and the ease of creating user defined exceptions in CORBA, this will not be an impediment to future work. Likewise, three pieces of information are currently\nentered on the command line when starting the HSI or the server. On starting the HSI, PROTOTYPEHOME and CAPSUser tell the system where the prototype PSDL files are located and who the current user is. In the event that PROTOTYPEHOME is not entered, the system will look in the user's home directory as a default. Again, the default is to the home directory of who ever starts the CAPS server. These could easily be incorporated into the respective GUIs in future work.\n\nThe sequence of events that brings the entire system on line are quite straightforward. First, on the machine that is hosting the server, start the naming service. Second, in another process, e.g., a separate DOS window, start the server implementation. Third, start the HSI on another machine (it can be started on the same machine in a third process). For all three, you must include the desired communication port. It must be the same for three processes. Additionally, for the client HSI you must include the internet location of the host running the server. More advanced implementations can eliminate these requirements. The following are examples of the actual semantics needed. To invoke the naming service, use \"tnameserv -ORBInitialPort 1050.\" For the server, use \"java -DCAP$SJavaHome=$CAPSHOME\\caps CapsServer -ORBInitialPort 1050\". Lastly, for the HSI use \"java -PROTOTYPEHOME=\\jdk2\\caps -DCAP$SUser=kreeger caps.Caps -ORBInitialHost 131.120.8.58 -ORBInitialPort 1050\".\nTHIS PAGE INTENTIONALLY LEFT BLANK\nVI. CONCLUSIONS AND FUTURE WORK\n\nOur initial tests are very encouraging. We were able to easily integrate the existing Java HSI running on a Windows NT machine into a client-server arrangement with the server running on a Sun Solaris Unix machine. We successfully created prototypes in the graphical editor of the HSI and saved the resulting PSDL files both to the HSI’s memory and transferred it over the network, where the server stored in its memory. We successfully opened PSDL files from both locations and displayed them in the graphical editor. Additionally, we sent PSDL files over the network to the server where they were translated and the corresponding Ada files generated. Thus, there appears to be little doubt about the ability of the current CAPS to be implemented in a client-server design that functions over any size network, including ultimately the Internet. The machinery that makes this not only possible, but even a reasonable effort, is CORBA. CORBA makes it feasible to convert the current CAPS to a client–server architecture while preserving much of the existing codebase. It is straightforward to instantiate a CAPS object on the server and then send a reference object to the CAPS object to any client. The users on the client side interact with the HSI’s extremely intuitive interface and whenever they need CAPS functionality, such as translate, the HSI simply invokes the method on the CAPS object reference that was received from the server. Thus much of the more complicated code that has been developed for the stand-alone CAPS can continue to be used. To this code, the origins of the request are irrelevant. As long as the proper parameters are passed in, the expected result will be produced and where the result is ultimately sent doesn’t matter. This arrangement\nallows the HSI to manage the user inputs to a prototype design locally. This is a very efficient manner for this type of operations. The more heavy duty, less frequently invoked functionality can reside on the server side of the network. The additional benefit of this design is that as more effective means of executing these services are implemented or additional requirements are discovered, it is a much simpler matter to update the single copy of the code located on the server side compared to trying to update code on a variety of different client machines across an entire network. As long as the interfaces remain unchanged, any alterations in one tier of the architecture will remain transparent to the other tiers.\n\nAs for the future, much remains to be done in order to fully realize the potential of a distributed CAPS. The work done thus far has clearly shown the potential that exists. However, to become a practical system for creating and managing prototyping for large software projects, a distributed CAPS must be fully functional and much more robust than at present. The next logical phase of this research should focus on two parallel tracks.\n\nOn the HSI the effort should concentrate on implementing the rest of the existing functionality for the current CAPS and on engineering production quality robustness into the HSI. The implementations of the commit and translate functions in this work provide an example of how to invoke from the HSI existing CAPS methods on a CAPS server and return the results to the HSI. Incorporating additional methods into the IDL interface definition and recompiling it are straightforward processes. This will produce the files necessary to implement the additional methods on the server side and the HSI. The second part of the effort for improving the HSI is easily done concurrently with the\nfirst part. As additional methods are included into the HSI, every effort should be made\nto ensure production quality robustness. The ease of creating user defined exceptions\nin both Java and CORBA simplify this effort tremendously.\n\nIn parallel with the HSI work, there remain tasks to be completed on the CAPS\nsoftware. First, while comprehensive theoretical work has been done on every aspect\nof CAPS, there remains functionality that either needs to be completed or enhanced.\nThis is especially true in regards to the reusable database. Finishing this work in\nconjunction with the HSI work provides the opportunity to tightly coordinate efforts.\nSecondly, the CAPS method implementations should be separated out from the CAPS\nserver. This would allow the CAPS server to be as efficient as possible and easily scale\nto a larger number of users. Furthermore, by isolating the actual method of\nimplementations from the CAPS server, they can be modified and updated more easily.\n\nIn conclusion, the endeavor to deploy a distributed CAPS is both feasible and\nnecessary. The emergence of the Java/CORBA technology supplies the means by\nwhich migrating CAPS from an isolated system to a fully functional distributed system\nbecomes not just possible, but quite manageable. That is fortunate timing, for if CAPS\nis to continue to be a driving force in software engineering research it must adapt to the\nnew realities of a networked world.\nAPPENDIX A: EXPANDED USE CASES\n\nSelected used cases are detailed below in expanded format:\n\nUse Case: **U3. Open project**\n\nActors: User\n\nType: primary and essential\n\nPurpose: Allow user to open a project\n\nOverview: After logging into CAPS, user can select an existing project and open it, if he has the proper authorization from the project manager. If the user has project manager privileges, they can open a new project.\n\nCross Reference: Functions: R2.3, R4.2, R4.3\n\nUse Cases: User must have completed the Start-up and Log in use cases\n\nSection: Main\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. This use case begins after the user has successfully started and logged into CAPS</td>\n<td></td>\n</tr>\n<tr>\n<td>2. The user chooses to open a new or existing prototype</td>\n<td></td>\n</tr>\n</tbody>\n</table>\na. If the user chooses a new prototype, see section Open New Prototype\n\nb. If the user chooses an existing prototype, see section Open Existing Prototype\n\n**Section: Open New Prototype**\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The user selects the new prototype option</td>\n<td>2. The system verifies the user has project manager level privileges.</td>\n</tr>\n<tr>\n<td>3. The system prompts the user for new prototype information</td>\n<td>4. The selected prototype is loaded at the users workstation</td>\n</tr>\n<tr>\n<td>5. A new prototype is created</td>\n<td>6. The users workstation</td>\n</tr>\n</tbody>\n</table>\n\n**Section: Open Existing Prototype**\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The user selects the open existing prototype option</td>\n<td>2. System presents the user with a list of existing prototypes within a file structure that can be navigated</td>\n</tr>\n<tr>\n<td>3. The user highlights the desired prototype and selects to open it</td>\n<td>4. The selected prototype is loaded at the users workstation</td>\n</tr>\n</tbody>\n</table>\nUse Case: U4. Modify prototype\n\nActors: User\n\nType: primary and essential\n\nPurpose: Allow user to modify a prototype\n\nOverview: After opening a prototype, the user will be able to make changes to the graphical interface of the control flow diagram or to the text boxes associated with either objects or data streams in the diagram. These changes will be automatically reflected in the PSDL code. The user can record user comments, stakeholder comments and requirements for the system being prototyped. Additionally, the user can directly access the PSDL code and change it manually.\n\nCross Reference: Functions: R1.1, R1.2, R1.3, R1.4, R1.5, R1.6, R1.7, R1.21, R4.4, R4.5\n\nUse Cases: User must have completed the Start-up, Log in and Open Project use cases\n\nSection: Main\n\nTypical Course of Action\n\nActor Action System Response\n\n1. This use case starts after the user has opened a prototype\n2. The user can make changes graphically or textually to the control flow diagram or may edit the actual PSDL code\n a. If user makes graphical changes, see section Graphical Changes\n b. If user makes textual changes, see section Textual Changes\n c. If the user edits the PSDL code, see section Edit PSDL Code\n\nSection: Graphical Changes\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. User selects graphical input from the menu of inputs, such as circle or line, or selects an existing graphical representation within the control flow diagram and manipulates it within the diagram</td>\n<td>2. The changes made by the user are displayed in the diagram and the PSDL code in main memory is generated and/or modified</td>\n</tr>\n</tbody>\n</table>\nSection: Textual Changes\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The user chooses an existing graphical object from the control flow diagram and selects to add textual input to it</td>\n<td>2. The text box for the graphical object selected is displayed</td>\n</tr>\n<tr>\n<td>3. The user makes the desired changes to the textual input box and confirms done when the input is completed</td>\n<td>4. The text box is no longer displayed, the changes are accepted, the PSDL code is generated and/or modified in main memory and if applicable the diagram presentation is modified</td>\n</tr>\n</tbody>\n</table>\n\nSection: Edit PSDL Code\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The user selects the option to directly edit the PSDL code from a CAPS menu</td>\n<td>2. The PSDL code for the prototype is displayed within a text editor</td>\n</tr>\n<tr>\n<td>3. The user makes changes to the PSDL code and selects save or closes the editor when done</td>\n<td>4. The PSDL code is modified in main memory</td>\n</tr>\n<tr>\n<td></td>\n<td>5. The modified PSDL code is validated for correctness before the user can exit the text editor</td>\n</tr>\n</tbody>\n</table>\nUse Case: U5. Retrieve component from reuse database\n\nActors: User\n\nType: primary and essential\n\nPurpose: To retrieve reusable components from library\n\nOverview: The user accesses the reuse database and inputs search parameters. CAPS responds with no match, unique match or a list of possible matches. CAPS generates an alert if there is an error in transmission and an acknowledgement if the transfer is successful.\n\nCross Reference: Functions: R1.21, R3.2, R3.4, R3.6\n\nUse Cases: User must have completed the Start-up, Log in and Open Project use cases\n\nSection: Main\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The user selects option from CAPS menu to retrieve component from reusable component library</td>\n<td>2. An input box is displayed for the user to input the desired parameters of the component to be returned</td>\n</tr>\n<tr>\n<td>3. The user inputs the desired component parameters and selects retrieve</td>\n<td>4. The parameters are sent to the reuse component library, possible over a network to a remote site</td>\n</tr>\n<tr>\n<td></td>\n<td>5. The parameters are accepted, a query formulated and the reuse component library searched</td>\n</tr>\n</tbody>\n</table>\n7. The user selects the desired component, if one available\n6. The user is informed that there was a match, multiple possible matches or no match\n8. A copy of the selected component is returned to the user\n9. The user is notified that the transfer was successful\n\nAlternate Courses\n\n- Line 9. If the transfer is unsuccessful, the user is notified. The type of error is displayed, if known\n\nUse Case: U7. Modify GUI for displaying prototype execution\nActors: User\nType: primary and essential\nPurpose: To modify the GUI generated to display prototype functionality\nOverview: User selects and then edits the files that provide functionality for displaying prototype execution\nCross Reference: Functions: R1.4, R1.5, R1.6, R1.7, R1.8, R1.9\nUse Cases: User must have completed the Start-up, Log in and Open Project use cases and have completed the Generate Executable Prototype use case sometime previously (not necessarily the same session)\nSection: Main\n\nTypical Course of Action\n\nActor Action\tSystem Response\n\n1. This use case starts after the user has opened a prototype\n2. The user can make changes to the source code to affect prototype functionality or to the prototype graphical interface\n a. If user makes functionality changes, see section Functional Changes\n b. If user makes graphical interface changes, see section Interface Changes\n\nSection: Functional Changes\n\nTypical Course of Action\n\nActor Action\tSystem Response\n\n1. The user selects the edit source file option from a CAPS menu\n2. A list of normal programming source files (e.g. Ada or Java) within the current prototype is displayed\n3. The user selects the source file to edit\n5. The user makes changes to the file\n6. The user saves the file\n8. The user quits the file\n9. The user quits the editor\n4. The selected file is opened in a text editor\n7. The file is written to persistent storage\n10. The user is queried about saving any unsaved changes, which will be saved to persistent storage and the editor is closed\n\nSection: Interface Changes\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The user selects the edit interface option from a CAPS menu</td>\n<td>2. A GUI builder is invoked with the current prototype GUI opened</td>\n</tr>\n<tr>\n<td>3. The user makes the desired changes to the prototype GUI</td>\n<td>4. The user selects the generate code option from the GUI builder</td>\n</tr>\n<tr>\n<td>5. Source code for the prototype GUI, which is controlled by the CAPS generated control source code, is automatically generated</td>\n<td>6. The user saves the file(s)</td>\n</tr>\n<tr>\n<td>7. The file(s) is written to persistent storage</td>\n<td>8. The user quits the GUI builder</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\nUse Case: U8. Generate Executable Prototype\n\nActors: User\n\nType: primary and essential\n\nPurpose: Prepare a prototype for execution\n\nOverview: The user translates the prototype in order to create source code in an implementation language from the PSDL and link it. The user will then verify through CAPS that all static hard real time constraints are met. The user will then compile the prototype source code.\n\nCross Reference: Functions: R1.9, R1.10, R1.11\nUse Cases: User must have completed the Start-up, Log in and Open Project use cases\n\nSection: Main\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The user selects the translate option from a CAPS menu</td>\n<td>2. PSDL code for prototype is used to generate 3rd generation object oriented language source code</td>\n</tr>\n<tr>\n<td>3. The user selects the schedule option from a CAPS menu</td>\n<td>4. All static hard real time constraints are verified as met</td>\n</tr>\n<tr>\n<td>5. The user selects the compile option from a CAPS menu</td>\n<td>6. All source files are compiled and executable files created</td>\n</tr>\n</tbody>\n</table>\nAlternate Courses\n\n- Line 4. Some static hard real time constraint is missed. CAPS generates an alert for the user.\n\nUse Case: U9. Execute the prototype\n\nActors: User\n\nType: primary and essential\n\nPurpose: Execute the prototype and perform analysis of system constraints\n\nOverview: The user will execute the prototype. As the user test the prototype functionality, CAPS will verify that all dynamic hard real time, concurrency and network constraints are met. CAPS will allow the user to record stakeholder and/or user comments.\n\nCross Reference: Functions: R1.1, R1.2, R1.3, R1.12, R1.13, R1.14, R1.15, R1.16\n\nUse Cases: User must have completed the Start-up, Log in and Open Project use cases and have completed the Generate Executable Prototype use case sometime previously (if not immediately after generating the executable prototype, you may execute a prototype that doesn't have the most recent changes)\nSection: Main\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The user selects the execute option from a CAPS menu</td>\n<td>2. The prototype GUI interface is generated and execution of the system being designed begins</td>\n</tr>\n<tr>\n<td>3. The user test the functionality of the designed system with manual inputs or scripted tests</td>\n<td>4. Dynamic hard real time constraints are verified met</td>\n</tr>\n<tr>\n<td>5. If the designed system is multi-threaded, concurrency constraints are verified met</td>\n<td>6. If the designed system is distributed, network constraints are verified met</td>\n</tr>\n<tr>\n<td>7. The user selects the record comments option from a CAPS menu</td>\n<td>8. A menu is displayed that allows the choice of selecting user or stakeholder comment inputs</td>\n</tr>\n<tr>\n<td>9. The comments are entered and the comment entry box deselected</td>\n<td>10. The comments are saved to persistent storage and become part of the project record</td>\n</tr>\n</tbody>\n</table>\n\nAlternate Courses\n\n- Line 4. Dynamic hard real time constraints are not met. CAPS generates an alert for the user.\n• Line 5. Concurrency constraints are not met. CAPS generates an alert for the user.\n\n• Line 6. Network constraints are not met. CAPS generates an alert for the user.\n\nUse Case: U10. Manage project changes\n\nActors: User, Project Manager\n\nType: primary and essential\n\nPurpose: Allow Project Manager to control configuration and version control for a project\n\nOverview: User (possibly more than one) will submit module(s) to the Project Manager for incorporation into the project prototype. The user may elect to return the entire prototype after making changes to only some of the modules. In this case the Project Manager must identify which modules are changed or new. If the module does not already exist in the project database, the Project Manager will merge the submitted module(s) into one module, resolving any conflicts. CAPS will assign and track a version number and insert the module into the project database, making ties to all other modules that may exist in the project database. If the module previously existed in the project database, the Project Manager will merge all submitted modules with the existing one, resolving any conflicts. CAPS will update the version number. If an existing module is submitted to the Project Manager, CAPS will verify that all other modules that it depends on are the most up to date.\nversion. CAPS will generate an alert if there is an error in\ntransmitting a module and an acknowledgement if there is no error.\n\nCross Reference: Functions: R1.19, R1.20, R3.1, R3.3, R3.4, R3.6, R4.3, R4.4, R4.6,\nR4.7, R4.8\n\nUse Cases: Project Manager must have completed the Start-up,\nLog in and Open Project use cases\n\nSection: Main\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. This use case begins with the Project Manager selecting the option</td>\n<td>2. All modules submitted for a project that are pending action are displayed from a CAPS menu to review modules that have been submitted for the current project</td>\n</tr>\n<tr>\n<td>3. Project Manager determines module update state:</td>\n<td></td>\n</tr>\n<tr>\n<td>a. If a single module not previously in the project is submitted, see section Single New Module</td>\n<td>b. If multiple versions of a module not previously in the project are submitted, see section Multiple New Modules</td>\n</tr>\n</tbody>\n</table>\n\n84\nc. If a single module previously in the project is submitted, see section Single Old Module\n\nd. If multiple versions of a module previously in the project are submitted, see section Multiple Old Modules\n\nAlternate Courses\n\n- Line 2. If there was an error in receiving any module, the Project Manager is alerted\n\nSection: Single New Module\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The Project Manager selects the option to view the new module from a CAPS menu</td>\n<td>2. The module is displayed in a text format</td>\n</tr>\n<tr>\n<td>3. If the Project Manager decides to include the module in the project, she selects the add option from a CAPS menu</td>\n<td>4. The Project Manager is asked where to save the file and exactly which project to include it in</td>\n</tr>\n<tr>\n<td>5. The Project Manager specifies the location to save to and the project into which the module is to be included</td>\n<td>6. The module is saved and included as directed</td>\n</tr>\n</tbody>\n</table>\n7. The module will be assigned a version number automatically.\n8. The module will be registered with the project automatically.\n\nSection: Multiple New Modules\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The Project Manager selects the option to view the new</td>\n<td>2. The modules are displayed in a text format as</td>\n</tr>\n<tr>\n<td>modules from a CAPS menu</td>\n<td>selected</td>\n</tr>\n<tr>\n<td>3. If the Project Manager decides to include the modules</td>\n<td>4. The Project Manager is asked which modules to</td>\n</tr>\n<tr>\n<td>in the project, he selects the merge option from a CAPS</td>\n<td>merge</td>\n</tr>\n<tr>\n<td>menu</td>\n<td></td>\n</tr>\n<tr>\n<td>5. After merging the modules into a single prototype, the</td>\n<td>7. The module is saved and included as directed</td>\n</tr>\n<tr>\n<td>Project Manager is asked where to save the file and exactly</td>\n<td></td>\n</tr>\n<tr>\n<td>which project to include it in</td>\n<td></td>\n</tr>\n<tr>\n<td>8. The module will be assigned a version number automatically</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n9. The module will be registered with the project automatically\n\nAlternate Courses\n\n- Line 5. If the modules cannot be successfully merged automatically, the Project Manager is sent an alert along with information about the conflict(s)\n\nSection: Single Old Module\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The Project Manager selects the option to view the new module from a CAPS menu</td>\n<td>2. The module is displayed in a text format</td>\n</tr>\n<tr>\n<td>3. If the Project Manager decides to replace the existing module in the project, she selects the merge option from a CAPS menu</td>\n<td>4. The Project Manager is asked to specify the modules to merge</td>\n</tr>\n<tr>\n<td>6. The Project Manager specifies the location to save to and the project into which the module is to be included</td>\n<td>5. After merging the modules into a single prototype, the Project Manager is asked where to save the file and exactly which project to include it in</td>\n</tr>\n<tr>\n<td>7. The module is saved and included as directed</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n8. The module will be assigned an updated version number automatically\n\nAlternate Courses\n\n- Line 3. The Project Manager can elect to simply replace the existing module with the new one\n- Line 5. If the modules cannot be successfully merged automatically, the Project Manager is sent an alert along with information about the conflict(s)\n\nSection: Multiple Old Modules\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The Project Manager selects the option to view the new modules from a CAPS menu</td>\n<td>2. The modules are displayed in a text format as selected</td>\n</tr>\n<tr>\n<td>3. If the Project Manager decides to include the modules in the project, he selects the merge option from a CAPS menu</td>\n<td>4. The Project Manager is asked to specify the new modules to merge into a single module</td>\n</tr>\n<tr>\n<td>5. After merging the modules into a single module, the Project Manager is asked which existing module to merge with the single new module</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n7. The Project Manager specifies the location to save to and the project into which the module is to be included.\n\n6. After merging the modules into a single prototype, the Project Manager is asked where to save the file and exactly which project to include it in.\n\n8. The module is saved and included as directed.\n\n9. The module will be assigned an updated version number automatically.\n\nAlternate Courses\n\n- Line 4. The Project Manager may elect to merge the new modules and the existing module at the same time.\n\n- Line 5. If the modules cannot be successfully merged automatically, the Project Manager is sent an alert along with information about the conflict(s).\n\n- Line 6. If the modules cannot be successfully merged automatically, the Project Manager is sent an alert along with information about the conflict(s).\n\nUse Case: **U11. Manage reuse database changes**\n\nActors: User, Software Librarian\n\nType: primary and essential\n\nPurpose: Allow Software Librarian to control configuration and version control for the reuse database\nOverview: User submits a new module, or an existing one that was modified, to the Software Librarian. When the Software Librarian accepts the module for inclusion in the reuse database, a version control number is assigned or updated as necessary and the module is saved to the reuse library. If the module was an update of an existing one, all users of the old version are alerted. The Software Librarian can also delete modules.\n\nCross Reference: Functions: R1.22, R1.23, R3.1, R3.3, R3.4, R3.6\n\nUse Cases: Software Librarian must have completed the Start-up and Log in use cases\n\nSection: Main\n\nTypical Course of Action\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. This use case begins with the Software Librarian selecting the option that are pending action are displayed from a CAPS menu to review modules that have been submitted for inclusion in the reuse database</td>\n<td></td>\n</tr>\n<tr>\n<td>2. All modules submitted for inclusion</td>\n<td></td>\n</tr>\n<tr>\n<td>3. The Software Librarian selects the option to view the a module on the list format from a CAPS menu</td>\n<td></td>\n</tr>\n<tr>\n<td>4. The module is displayed in a text format</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n5. After review, the Software Librarian selects the add option from CAPS menu.\n\n6. The Software Librarian chooses to add the module as a new one or to replace an existing module with the new one:\n \n a. If the module is added as a completely new one, see section Add New Module\n \n b. If the module is replacing an existing module, see section Replace Existing Module\n\n**Section: Add New Module**\n\n**Typical Course of Action**\n\n<table>\n<thead>\n<tr>\n<th>Actor Action</th>\n<th>System Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. The Software Librarian elects to add the submitted module as a new module</td>\n<td>2. The module is added to the reuse database and a version control number is assigned</td>\n</tr>\n</tbody>\n</table>\nSection: Replace Existing Module\n\nTypical Course of Action\n\nActor Action System Response\n1. The Software Librarian elects to replace an existing module with the submitted module\n2. The new module replaces the existing one in the reuse database\n3. The version control number is updated\n4. Users of the old version are alerted that there are changes to the module they checked out\nAPPENDIX B: CAPS SERVER IMPLEMENTATION SOURCE CODE\n\nThis appendix contains the IDL file that describes the methods defined in order to implement a distributed CAPS server. It also contains the source files and Javadoc generated documentation for the CAPS server.\n\n/**\n * The Interface Description Language (IDL) for a Distributed CAPS\n * @author Gary Kreeger\n * @version 1.0\n */\n\nmodule DistributedCaps\n{\n interface DistCaps\n {\n exception cantWriteFile {};\n exception cantReadFile {};\n\n typedef sequence<octet> prototype_file;\n typedef sequence<string> prototype_list;\n\n string translate (in prototype_file psdl_file, in string name,\n in string version, in string user) raises (cantWriteFile);\n\n prototype_list get_proto_list (in string user);\n\n prototype_file open_proto (in string name, in string user) raises (cantReadFile);\n\n string commit (in prototype_file psdl_file, in string name,\n in string version, in string user) raises (cantWriteFile);\n }\n};\n\n/**\n * The DistributedCaps Server main program. It instantiates a DisCapsImpl\n * object, starts the orb and registers the object with the orb.\n * @author Gary Kreeger\n * @version 1.0\n */\nimport DistributedCaps.*;\nimport org.omg.CosNaming.*;\nimport org.omg.CORBA.*;\n\npublic class CapsServer\n \n public static void main(String[] args)\n \n try\n \n // Initialize the ORB\n ORB orb = ORB.init(args, null);\n\n // Create the Caps object\n DistCapsImpl caps = new DistCapsImpl();\n orb.connect(caps);\n\n //get the root naming context\n org.omg.CORBA.Object objRef = orb.resolve_initial_references(\"NameService\");\n NamingContext ncRef = NamingContextHelper.narrow(objRef);\n\n // bind the Object Reference in Naming\n NameComponent nc = new NameComponent(\"DistCaps\", \"\");\n NameComponent path[] = {nc};\n ncRef.rebind(path, caps);\n\n //wait for invocations from client\n java.lang.Object sync = new java.lang.Object();\n synchronized (sync)\n {\n sync.wait();\n }\n\n } catch (Exception e)\n {\n System.err.println(\"Error: \" + e);\n e.printStackTrace(System.out);\n }\n\n }//end CapsServer\n\n/**\n * The Implementation for the distributed CAPS object.\n *\n * @author Gary Kreeger\n * @version 1.0\n */\n\nimport DistributedCaps.*;\nimport java.io.*;\nimport java.io.File;\nimport java.util.Vector;\nimport javax.swing.filechooser.FileSystemView;\n\npublic class DistCapsImpl extends _DistCapsImplBase\n\n94\n{ \n/**\n * the constructor for a distributed CAPS object\n */\n\nDistCapsImpl()\n{\n super();\n System.out.println(\"Caps Object Created\");\n}\n\n/**\n * Translate function for creating Ada files from a PSDL file\n *\n * @param psdl_file The PSDL file to be translated\n * @param name The name of the PSDL file\n * @param version The version number of the PSDL file being translated\n * @param user The name of the user at the client session\n * @return A string to confirm the file was transferred and translated\n * @throws DistributedCaps.DistCapsPackage.cantWriteFile\n */\n\npublic String translate (byte[] psdl_file, String name, String version, String user)\n throws DistributedCaps.DistCapsPackage.cantWriteFile\n{\n boolean tempBool = true;\n String protoHome;\n // MTS 8/25/99\n // added local variable userHome\n String userHome = \";\n\n try\n {\n String CapsServerFiles = System.getProperty(\"CAPSJavaHome\");\n if (CapsServerFiles == null) // CAPSJavaHome not set on command line\n {\n //default to the home directory\n File homeDir = FileSystemView.getFileSystemView().getHomeDirectory();\n protoHome = new String (homeDir.getAbsolutePath() + File.separator + version + \n File.separator + \".caps\");\n\n // MTS 8/25/99\n // added code to initialize userHome\n userHome = (homeDir + File.separator + user);\n\n File protoDir = new File (protoHome);\n if (!protoDir.exists ()\n {\n protoDir.mkdir ()\n }\n else\n {\n protoHome = new String (CapsServerFiles + File.separator + user + \n\n95\nFile.separator + \".caps\")\n\n // MTS 8/25/99\n // added code to initialize userHome\n userHome = (CapsServerFiles + File.separator + user);\n\n File protoDir = new File (protoHome);\n if (!protoDir.exists ())\n {\n protoDir.mkdir ();\n }\n\n //ensure the file is created, read the byte array into a FileOutputStream\n //and then read the FileOutputStream into the file\n String proto = name;\n File PSDL_Demo = new File (protoHome + File.separator + name + \n File.separator + version + File.separator + proto + \".psdl\");\n tempBool = PSDL_Demo.createNewFile();\n FileOutputStream fos = new FileOutputStream (PSDL_Demo);\n fos.write (psdl_file);\n fos.close();\n }\n catch (Exception e)\n {\n throw new DistributedCaps DistCapsPackage.cantWriteFile();\n }\n\n // MTS 8/25/99\n // replace protoHome with userHome in the following call to translate.script\n // String command = \"translate.script \" + protoHome + \", name + \"+ version; \n String command = \"translate.script \" + userHome + \", name + \"+ version;\n\n try\n {\n Runtime run = Runtime.getRuntime();\n run.exec(command);\n }\n catch (IOException ex)\n {\n System.out.println (ex);\n }\n\n return \"\\nThe PSDL file was successfully transferred to the server\\n\\n*/\n/**\n * Get the list of prototypes available remotely\n * \n * @param user The name of the user at the client session\n * \n * @return An array of prototype names that may be selected for opening\n */\npublic String [] get_proto_list(String user)\n{ \n String [] protolist;\n String CapsServerFiles = System.getProperty(\"CAPSJavaHome\");\n String protoHome;\n File protoDir;\n\n if (CapsServerFiles == null) // CAPSJavaHome not set on command line\n {\n File homeDir = FileSystemView.getFileSystemView().getHomeDirectory();\n protoHome = new String (homeDir + File.separator + user +\n File.separator + \".caps\");\n protoDir = new File (protoHome);\n if (!protoDir.exists ())\n {\n protoDir.mkdir ();\n }\n }\n else\n {\n protoHome = new String (CapsServerFiles + File.separator + user +\n File.separator + \".caps\");\n protoDir = new File (protoHome);\n if (!protoDir.exists ())\n {\n protoDir.mkdir ();\n }\n }\n\n // vector to hold prototype names\n Vector prototypeNames = new Vector (0, 2);\n // array to hold list of existing files\n File [] dirs = protoDir.listFiles ();\n\n if (dirs.length == 0) // no files exist\n {\n return protolist = new String [0];\n }\n else\n {\n for (int ix = 0; ix < dirs.length; ix++)\n {\n String protoName = \"\";\n protoName = dirs [ix].getName ();\n File subDirs [] = dirs [ix].listFiles ();\n for (int jx = 0; jx < subDirs.length; jx++)\n {\n prototypeNames.addElement (protoName.concat\n (File.separator + subDirs [jx].getName ());\n }\n }\n\n // get the vector into an object array and then convert it to a string array\n Object [] temp_proto_list = prototypeNames.toArray ();\n protolist = new String [temp_proto_list.length];\n\n for (int ix = 0; ix < temp_proto_list.length; ix++)\n \n 97\n\n\n```java\n{\n protolist[ix] = String.valueOf(temp_proto_list[ix]);\n}\n\nreturn protolist;\n}\n}//end get_proto_list\n\n/**\n * Open the selected prototype\n * \n * @param name The name of the prototype opened\n * @param user The name of the user at the client session\n * \n * @return A byte array holding the selected prototype PSDL file\n * \n * @throws DistributedCaps.DistCapsPackage.cantReadFile\n */\n\npublic byte[] open_proto(String name, String user)\n throws DistributedCaps.DistCapsPackage.cantReadFile\n{\n try\n {\n byte[] proto_file;\n String CapsServerFiles = System.getProperty(\"CAPSJavaHome\");\n String protoHome;\n File protoDir;\n\n if (CapsServerFiles == null) // CAPSJavaHome not set on command line\n {\n File homeDir = FileSystemView.getFileSystemView().getHomeDirectory();\n protoHome = new String (homeDir + File.separator + user +\n File.separator + \".caps\");\n protoDir = new File (protoHome);\n if (!protoDir.exists ())\n {\n protoDir.mkdir ();\n }\n }\n else\n {\n protoHome = new String (CapsServerFiles + File.separator + user +\n File.separator + \".caps\");\n protoDir = new File (protoHome);\n if (!protoDir.exists ())\n {\n protoDir.mkdir ();\n }\n }\n\n if (name == null)\n {\n return proto_file = new byte[0];\n }\n }\n```\nelse\n{\n // create file object with which to manipulate the selected file\n File selectedDir = new File (protoHome + File.separator + name);\n File file = new File (selectedDir.getAbsolutePath() + File.separator +\n selectedDir.getParentFile ().getName () + \".psdl\");\n if (!file.exists ()\n return proto_file = new byte[0];\n } else\n {\n //read the opened file into a FileInputStream and then read the\n //FileInputStream in new FileInputStream (file);\n proto_file = new byte[in.available ()];\n in.read (proto_file);\n return proto_file;\n }\n}\n}\n\ncatch (Exception e)\n{\n throw new DistributedCaps.DistCapsPackage.cantReadFile ();\n}\n\n}//end open_proto\n\n/**\n * Save a prototype's PSDL file on a local client to the remote server.\n *\n * @param psdl_file The PSDL file to be translated.\n * @param name The name of the PSDL file.\n * @param version The version number of the PSDL file being translated.\n * @param user The name of the user at the client session.\n * @return A string to confirm the file was transferred.\n *\n * @throws DistributedCaps.DistCapsPackage.cantWriteFile\n */\n\npublic String commit (byte[] psdl_file, String name, String version, String user)\n throws DistributedCaps.DistCapsPackage.cantWriteFile\n{\n boolean tempBool = true;\n String protoHome = \"\";\n String proto = name;\n String completePath = \"\";\n\n try\n {\n String CapsServerFiles = System.getProperty(\"CAPSJavaHome\");\n if (CapsServerFiles == null) // CAPSJavaHome not set on command line\n {\nFile homeDir = FileSystemView.getFileSystemView ().getHomeDirectory ();\n\nprotoHome = (homeDir + File.separator + user +\nFile.separator + \".caps\");\nFile protoDir = new File (protoHome);\nif (!protoDir.exists ())\n{\n protoDir.mkdir ();\n}\nelse\n{\n protoHome = (CapsServerFiles + File.separator + user +\nFile.separator + \".caps\");\n File protoDir = new File (protoHome);\n if (!protoDir.exists ())\n {\n tempBool = protoDir.mkdirs ();\n }\n}\n\ncompletePath = (protoHome + File.separator + name + File.separator + version);\nFile completeDirs = new File (completePath);\nif (!completeDirs.exists ()) // ensure the correct directory exist to save to\n{\n tempBool = completeDirs.mkdirs ();\n}\n\n// ensure the file is created, read the byte array into a FileOutputStream\n// and then read the FileOutputStream into the file\nFile PSDL_Demo = new File (completePath + File.separator + proto + \".psdl\");\ntempBool = PSDL_Demo.createNewFile ();\nFileOutputStream fos = new FileOutputStream (PSDL_Demo);\nfos.write (psdl_file);\nfos.close ();\n}\n\ncatch (Exception e)\n{\n System.out.println (e);\n throw new DistributedCaps.DistCapsPackage.cantWriteFile ();\n}\n\nreturn \"\\nThe PSDL file was successfully transferred to the server\\n\";\n} // end commit\nClass CapsServer\n\njava.lang.Object\n |\n +--CapsServer\n\npublic class CapsServer\nextends java.lang.Object\n\nThe DistributedCaps Server main program. It instantiates a DisCapsImpl object, starts the orb and registers the object with the orb.\n\nConstructor Summary\n\nCapsServer()\n\nMethod Summary\n\nstatic void main(java.lang.String[] args)\n\nMethods inherited from class java.lang.Object\ncloned, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait\n\nConstructor Detail\n\nCapsServer\n\npublic CapsServer()\n\nMethod Detail\n\nmain\n\npublic static void main(java.lang.String[] args)\nClass DistCapsImpl\n\njava.lang.Object \n |---org.omg.CORBA.portable.ObjectImpl \n | |---org.omg.CORBA.DynamicImplementation \n | | |---DistributedCaps._DistCapsImplBase \n | | |---DistCapsImpl\n\npublic class DistCapsImpl \nextends DistributedCaps._DistCapsImplBase\n\nThe implementation for the distributed CAPS object.\n\nSee Also:\n Serialized Form\n\n### Method Summary\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>{java.lang.String}</code></td>\n<td><strong>commit</strong>(<code>byte[]</code> psdl_file, <code>java.lang.String</code> name, \\</td>\n</tr>\n<tr>\n<td></td>\n<td><code>java.lang.String</code> version, <code>java.lang.String</code> user) \\</td>\n</tr>\n<tr>\n<td></td>\n<td>Save a prototype's PSDL file on a local client to the remote server</td>\n</tr>\n<tr>\n<td><code>{java.lang.String[]}</code></td>\n<td><strong>get_proto_list</strong>(<code>java.lang.String</code> user) \\</td>\n</tr>\n<tr>\n<td></td>\n<td>Get the list of prototypes available remotely</td>\n</tr>\n<tr>\n<td><code>{byte[]}</code></td>\n<td><strong>open_proto</strong>(<code>java.lang.String</code> name, <code>java.lang.String</code> user) \\</td>\n</tr>\n<tr>\n<td></td>\n<td>Open the selected prototype</td>\n</tr>\n<tr>\n<td><code>{java.lang.String}</code></td>\n<td><strong>translate</strong>(<code>byte[]</code> psdl_file, <code>java.lang.String</code> name, \\</td>\n</tr>\n<tr>\n<td></td>\n<td><code>java.lang.String</code> version, <code>java.lang.String</code> user) \\</td>\n</tr>\n<tr>\n<td></td>\n<td>Translate function for creating ADA files from a PSDL file</td>\n</tr>\n</tbody>\n</table>\n\nMethods inherited from class DistributedCaps._DistCapsImplBase\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>_ids, invoke</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nMethods inherited from class org.omg.CORBA.portable.ObjectImpl\n\n_create_request, _create_request, _duplicate, _get_delegate, _get_domain_managers, _get_interface_def, _get_policy, _hash, _invoke, _is_a, _is_equivalent, _is_local, _non_existent, _orb, _release, _releaseReply, _request, _request, _servant_postinvoke, _servant_preinvoke, _set_delegate, _set_policy_override, equals, hashCode, toString\n\nMethods inherited from class java.lang.Object\n\nclose, finalize, getClass, notify, notifyAll, wait, wait, wait\n\nMethod Detail\n\ntranslate\n\n```java\npublic java.lang.String translate(byte[] psdl_file,\n java.lang.String name,\n java.lang.String version,\n java.lang.String user)\n throws DistributedCaps.DistCapsPackage.cantWriteFile\n```\n\nTranslate function for creating ADA files from a PSDL file\n\n**Overrides:**\ntranslate in class DistributedCaps._DistCapsImplBase\n\n**Parameters:**\n- psdl_file - The PSDL file to be translated\n- name - The name of the PSDL file\n- version - The version number of the PSDL file being translated\n- user - The name of the user at the client session\n\n**Returns:**\nA string to confirm the file was transferred and translated\n\n**Throws:**\nDistributedCaps.DistCapsPackage.cantWriteFile -\n\nget_proto_list\n\n```java\npublic java.lang.String[] get_proto_list(java.lang.String user)\n```\n\nGet the list of prototypes available remotely\n\n** Overrides:**\nget_proto_list in class DistributedCaps._DistCapsImplBase\n\n** Parameters:**\n- user - The name of the user at the client session\n\n** Returns:**\nAn array of prototype names that may be selected for opening\nopen_proto\n\npublic byte[] open_proto(java.lang.String name,\n java.lang.String user)\n throws DistributedCaps.DistCapsPackage.cantReadFile\n\nOpen the selected prototype\n\nOverrides:\n open_proto in class DistributedCaps._DistCapsImplBase\n\nParameters:\n name - The name of the prototype opened\n user - The name of the user at the client session\n\nReturns:\n A byte array holding the selected prototype PSDL file\n\nThrows:\n DistributedCaps.DistCapsPackage.cantReadFile -\n\ncommit\n\npublic java.lang.String commit(byte[] psdl_file,\n java.lang.String name,\n java.lang.String version,\n java.lang.String user)\n throws DistributedCaps.DistCapsPackage.cantWriteFile\n\nSave a prototype’s PSDL file on a local client to the remote server\n\nOverrides:\n commit in class DistributedCaps._DistCapsImplBase\n\nParameters:\n psdl_file - The PSDL file to be translated\n name - The name of the PSDL file\n version - The version number of the PSDL file being translated\n user - The name of the user at the client session\n\nReturns:\n A string to confirm the file was transferred\n\nThrows:\n DistributedCaps.DistCapsPackage.cantWriteFile -\nAPPENDIX C: IDL-TO-JAVA COMPILER GENERATED SOURCE CODE\n\nThis appendix contains the source files and corresponding Javadoc generated documentation for the files created by the IDL-to-Java compiler when creating the distributed CAPS server.\n\n/*\n * File: /DISTRIBUTEDCAPS/DISTCAPS.JAVA\n * From: DISTCAPS.IDL\n * Date: Wed Aug 18 20:38:43 1999\n * By: idltojava Java IDL 1.2 Aug 18 1998 16:25:34\n */\n\npackage DistributedCaps;\npublic interface DistCaps extends org.omg.CORBA.Object, org.omg.CORBA.portable.IDLEntity {\n String translate(byte[] psdl_file, String name, String version, String user)\n throws DistributedCaps.DistCapsPackage.cantWriteFile;\n String[] get_proto_list(String user);\n byte[] open_proto(String name, String user)\n throws DistributedCaps.DistCapsPackage.cantReadFile;\n String commit(byte[] psdl_file, String name, String version, String user)\n throws DistributedCaps.DistCapsPackage.cantWriteFile;\n}\n\n/*\n * File: /DISTRIBUTEDCAPS/_DISTCAPSIMPLBASE.JAVA\n * From: DISTCAPS.IDL\n * Date: Wed Aug 18 20:38:43 1999\n * By: idltojava Java IDL 1.2 Aug 18 1998 16:25:34\n */\n\npackage DistributedCaps;\npublic abstract class _DistCapsImplBase extends org.omg.CORBA.DynamicImplementation implements DistributedCaps.DistCaps {\n // Constructor\n public _DistCapsImplBase() {\n super();\n }\n // Type strings for this class and its superclasses\n private static final String _type_ids[] = {\n \"IDL:DistributedCaps/DistCaps:1.0\"\n };\n\n public String[] _ids() { return (String[])_type_ids.clone(); }\n\n private static java.util.Dictionary _methods = new java.util.Hashtable();\n static {\n\n105\n_methods.put(\"translate\", new java.lang.Integer(0));\n_methods.put(\"get_proto_list\", new java.lang.Integer(1));\n_methods.put(\"open_proto\", new java.lang.Integer(2));\n_methods.put(\"commit\", new java.lang.Integer(3));\n}\n// DS Dispatch call\npublic void invoke(org.omg.CORBA.ServerRequest r) {\n switch (((java.lang.Integer) _methods.get(r.op_name())).intValue()) {\n case 0: // DistributedCaps.DistCaps.translate\n { \n org.omg.CORBA.NVList _list = _orb().create_list(0);\n org.omg.CORBA.Any _psdl_file = _orb().create_any();\n _psdl_file.type(DistributedCaps.DistCapsPackage.prototype_fileHelper.type());\n _list.add_value(\"psdl_file\", _psdl_file, org.omg.CORBA.ARG_IN.value);\n org.omg.CORBA.Any _name = _orb().create_any();\n _name.type(org.omg.CORBA.ORB.init().get_primitive_tc(org.omg.CORBA.TCKind.tk_string));\n _list.add_value(\"name\", _name, org.omg.CORBA.ARG_IN.value);\n org.omg.CORBA.Any _version = _orb().create_any();\n _version.type(org.omg.CORBA.ORB.init().get_primitive_tc\n (org.omg.CORBA.TCKind.tk_string));\n _list.add_value(\"version\", _version, org.omg.CORBA.ARG_IN.value);\n org.omg.CORBA.Any _user = _orb().create_any();\n _user.type(org.omg.CORBA.ORB.init().get_primitive_tc\n (org.omg.CORBA.TCKind.tk_string));\n _list.add_value(\"user\", _user, org.omg.CORBA.ARG_IN.value);\n r.params(_list);\n byte[] psdl_file;\n psdl_file = DistributedCaps.DistCapsPackage.prototype_fileHelper.extract(_psdl_file);\n String name;\n name = _name.extract_string();\n String version;\n version = _version.extract_string();\n String user;\n user = _user.extract_string();\n String _result;\n try {\n _result = this.translate(psdl_file, name, version, user);\n }\n catch (DistributedCaps.DistCapsPackage.cantWriteFile e0) {\n org.omg.CORBA.Any _except = _orb().create_any();\n DistributedCaps.DistCapsPackage.cantWriteFileHelper.insert(_except, e0);\n r.except(_except);\n return;\n }\n org.omg.CORBA.Any _result = _orb().create_any();\n _result.insert_string(_result);\n r.result(_result);\n } break;\n case 1: // DistributedCaps.DistCaps.get_proto_list\n { \n org.omg.CORBA.NVList _list = _orb().create_list(0);\n org.omg.CORBA.Any _user = _orb().create_any();\n _user.type(org.omg.CORBA.ORB.init().get_primitive_tc\n (org.omg.CORBA.TCKind.tk_string));\n _list.add_value(\"user\", _user, org.omg.CORBA.ARG_IN.value);\n r.params(_list);\n String user,\nuser = user.extract_string();\nString[1] __result;\n__result = this.get_proto_list(user);\norg.omg.CORBA.Any __result = _orb().create_any();\nDistributedCaps.DistCapsPackage.prototype_listHelper.insert(__result, __result);\nr.result(__result);\n} \nbreak;\ncase 2: // DistributedCaps.DistCaps.open_proto \n{\norg.omg.CORBA.NVList__list = _orb().create_list(0);\norg.omg.CORBA.Any__name = _orb().create_any();\n__name.type( org.omg.CORBA.ORB.init().get_primitive_tc( org.omg.CORBA.TCKind.tk_string ));\n__list.add_value(\"name\",__name, org.omg.CORBA.ARG_IN.value);\norg.omg.CORBA.Any__user = _orb().create_any();\n__user.type( org.omg.CORBA.ORB.init().get_primitive_tc( org.omg.CORBA.TCKind.tk_string ));\n__list.add_value(\"user\",__user, org.omg.CORBA.ARG_IN.value);\n}\nparams(__list);\nString name;\nname = __name.extract_string();\nString user;\nuser = __user.extract_string();\nbyte[] __result;\ntry {\n__result = this.open_proto(name, user);\n}\ncatch(DistributedCaps.DistCapsPackage.cantReadFile e0) {\norg.omg.CORBA.Any__except = _orb().create_any();\nDistributedCaps.DistCapsPackage.cantReadFileHelper.insert(__except, e0);\nr.except(__except);\nreturn;\n}\norg.omg.CORBA.Any__result = _orb().create_any();\nDistributedCaps.DistCapsPackage.prototype_fileHelper.insert(__result, __result);\nr.result(__result);\n} \nbreak;\ncase 3: // DistributedCaps.DistCaps.commit \n{\norg.omg.CORBA.NVList__list = _orb().create_list(0);\norg.omg.CORBA.Any__psdl_file = _orb().create_any();\n__psdl_file.type(DistributedCaps.DistCapsPackage.prototype_fileHelper.type());\n__list.add_value(\"psdl_file\",__psdl_file, org.omg.CORBA.ARG_IN.value);\norg.omg.CORBA.Any__name = _orb().create_any();\n__name.type( org.omg.CORBA.ORB.init().get_primitive_tc( org.omg.CORBA.TCKind.tk_string ));\n__list.add_value(\"name\",__name, org.omg.CORBA.ARG_IN.value);\norg.omg.CORBA.Any__version = _orb().create_any();\n__version.type( org.omg.CORBA.ORB.init().get_primitive_tc( org.omg.CORBA.TCKind.tk_string ));\n__list.add_value(\"version\",__version, org.omg.CORBA.ARG_IN.value);\norg.omg.CORBA.Any__user = _orb().create_any();\n__user.type( org.omg.CORBA.ORB.init().get_primitive_tc( org.omg.CORBA.TCKind.tk_string ));\n__list.add_value(\"user\",__user, org.omg.CORBA.ARG_IN.value);\nr.params(__list);\nbyte[] psdl_file;\npsdl_file = DistributedCaps.DistCapsPackage.prototype_fileHelper.extract(__psdl_file);\nString name;\nname = _name.extract_string();\nString version;\nversion = _version.extract_string();\nString user;\nuser = _user.extract_string();\nString __result;\ntry {\n __result = this.commit(pSDL_file, name, version, user);\n}\ncatch (DistributedCaps.DistCapsPackage.cantWriteFile e0) {\n org.omg.CORBA.Any __except = __orb().create_any();\n DistributedCaps.DistCapsPackage.cantWriteFileHelper.insert(__except, e0);\n r.except(__except);\n return;\n}\norg.omg.CORBA.Any __result = __orb().create_any();\n__result.insert_string(__result);\nresult(__result);\n} break;\ndefault:\nthrow new org.omg.CORBA.BAD_OPERATION(0,\norg.omg.CORBA.CompletionStatus.COMPLETED_MAYBE);\n}\n*/\n\npackage DistributedCaps;\npublic class _DistCapsStub\n extends org.omg.CORBA.portable.ObjectImpl\n implements DistributedCaps.DistCaps {\n\n public _DistCapsStub(org.omg.CORBA.portable.Delegate d) {\n super();\n _set_delegate(d);\n }\n\n private static final String _type_ids[] = {\n \"IDL:DistributedCaps/DistCaps:1.0\"\n ;\n\n public String[] _ids() { return (String[]) _type_ids.clone(); }\n\n // IDL operations\n // Implementation of ::DistributedCaps::DistCaps::translate\n public String translate(byte[] pSDL_file, String name, String version, String user)\n throws DistributedCaps.DistCapsPackage.cantWriteFile {\n\n108\norg.omg.CORBA.Request r = _request(\"translate\");\nr.set_return_type(org.omg.CORBA.ORB.init().get_primitive_tc(org.omg.CORBA.TCKind.tk_string));\norg.omg.CORBA.Any _psdl_file = r.add_in_arg();\nDistributedCaps.DistCapsPackage.prototype_fileHelper.insert(_psdl_file, psdl_file);\norg.omg.CORBA.Any _name = r.add_in_arg();\n_name.insert_string(name);\norg.omg.CORBA.Any _version = r.add_in_arg();\n_version.insert_string(version);\norg.omg.CORBA.Any _user = r.add_in_arg();\n_user.insert_string(user);\nr.exceptions().add(DistributedCaps.DistCapsPackage.cantWriteFileHelper.type());\nr.invoke();\njava.lang.Exception __ex = r.env().exception();\nif (__ex instanceof org.omg.CORBA.UnknownUserException) {\n org.omg.CORBA.UnknownUserException __userEx = (org.omg.CORBA.UnknownUserException) __ex;\n if (__userEx.except.type().equals(DistributedCaps.DistCapsPackage.cantWriteFileHelper.type())) {\n throw DistributedCaps.DistCapsPackage.cantWriteFileHelper.extract(__userEx.except);\n }\n}\nString __result;\n__result = r.return_value().extract_string();\nreturn __result;\n\n// Implementation of ::DistributedCaps::DistCaps::get_proto_list\npublic String[] get_proto_list(String user) {\n org.omg.CORBA.Request r = _request(\"get_proto_list\");\nr.set_return_type(DistributedCaps.DistCapsPackage.prototype_listHelper.type());\norg.omg.CORBA.Any _user = r.add_in_arg();\n_user.insert_string(user);\nr.invoke();\nString[] __result;\n__result = DistributedCaps.DistCapsPackage.prototype_listHelper.extract(r.return_value());\nreturn __result;\n\n// Implementation of ::DistributedCaps::DistCaps::open_proto\npublic byte[] open_proto(String name, String user) throws DistributedCaps.DistCapsPackage.cantReadFile {\n org.omg.CORBA.Request r = _request(\"open_proto\");\nr.set_return_type(DistributedCaps.DistCapsPackage.prototype_fileHelper.type());\norg.omg.CORBA.Any _name = r.add_in_arg();\n_name.insert_string(name);\norg.omg.CORBA.Any _user = r.add_in_arg();\n_user.insert_string(user);\nr.exceptions().add(DistributedCaps.DistCapsPackage.cantReadFileHelper.type());\nr.invoke();\njava.lang.Exception __ex = r.env().exception();\nif (__ex instanceof org.omg.CORBA.UnknownUserException) {\n org.omg.CORBA.UnknownUserException __userEx = (org.omg.CORBA.UnknownUserException) __ex;\n if (__userEx.except.type().equals(DistributedCaps.DistCapsPackage.cantReadFileHelper.type())) {\n throw DistributedCaps.DistCapsPackage.cantReadFileHelper.extract(__userEx.except);\n }\n}\nbyte[] __result;\n__result = DistributedCaps.DistCapsPackage.prototype_fileHelper.extract(r.return_value());\nreturn __result;\n} // Implementation of ::DistributedCaps::DistCaps::commit\n\npublic String commit(byte[] psdl_file, String name, String version, String user) throws DistributedCaps.DistCapsPackage.cantWriteFile {\n org.omg.CORBA.Request r = _request(\"commit\");\n r.set_return_type(org.omg.CORBA.ORB.init().get_primitive_tc(org.omg.CORBA.TCKind.tk_string));\n org.omg.CORBA.Any _psdl_file = r.add_in_arg();\n DistributedCaps.DistCapsPackage.prototype_fileHelper.insert(_psdl_file, psdl_file);\n org.omg.CORBA.Any _name = r.add_in_arg();\n _name.insert_string(name);\n org.omg.CORBA.Any _version = r.add_in_arg();\n _version.insert_string(version);\n org.omg.CORBA.Any _user = r.add_in_arg();\n _user.insert_string(user);\n r.exceptions().add(DistributedCaps.DistCapsPackage.cantWriteFileHelper.type());\n r.invoke();\n java.lang.Exception __ex = r.env().exception();\n if (__ex instanceof org.omg.CORBA.UnknownUserException) {\n org.omg.CORBA.UnknownUserException __userEx = (org.omg.CORBA.UnknownUserException)__ex;\n if (__userEx.except.type().equals(DistributedCaps.DistCapsPackage.cantWriteFileHelper.type())) {\n throw DistributedCaps.DistCapsPackage.cantWriteFileHelper.extract(__userEx.except);\n }\n }\n String __result;\n __result = r.return_value().extract_string();\n return __result;\n}\n\n package DistributedCaps;\n public class DistCapsHelper {\n // It is useless to have instances of this class\n private DistCapsHelper() {}\n\n public static void write(org.omg.CORBA.portable.OutputStream out, DistributedCaps.DistCaps that) {\n out.write_Object(that);\n }\n\n public static DistributedCaps.DistCaps read(org.omg.CORBA.portable.InputStream in) {\n return DistributedCaps.DistCapsHelper.narrow(in.read_Object());\n }\n\n public static DistributedCaps.DistCaps extract(org.omg.CORBA.Any a) {\n org.omg.CORBA.portable.InputStream in = a.create_input_stream();\n return read(in);\n }\n\n public static void insert(org.omg.CORBA.Any a, DistributedCaps.DistCaps that) {\n org.omg.CORBA.portable.OutputStream out = a.create_output_stream();\n write(out, that);\n }\n\n /*\n * File: DISTRIBUTEDCAPS/DISTCAPSHELPER.JAVA\n * From: DISTCAPS.IDL\n * Date: Wed Aug 18 20:38:43 1999\n * By: idltojava Java IDL 1.2 Aug 18 1998 16:25:34\n */\n\n}\nprivate static org.omg.CORBA.TypeCode tc;\nsynchronized public static org.omg.CORBA.TypeCode type() {\n if (_tc == null)\n _tc = org.omg.CORBA.ORB.init().create_interface_tc(id, \"DistCaps\");\n return _tc;\n}\n\npublic static String id() {\n return \"IDL:DistributedCaps:1.0\";\n}\n\npublic static DistributedCaps.DistCaps narrow(org.omg.CORBA.Object that) throws org.omg.CORBA.BAD_PARAM {\n if (that == null)\n return null;\n if (that instanceof DistributedCaps.DistCaps)\n return (DistributedCaps.DistCaps) that;\n if (!that._is_a(id)) {\n throw new org.omg.CORBA.BAD_PARAM();\n }\n\n DistributedCaps.DistCaps result = new DistributedCaps._DistCapsStub(dup);\n return result;\n}\n\npackage DistributedCaps;\npublic final class DistCapsHolder\n implements org.omg.CORBA.portable.Streamable {\n // instance variable\n public DistributedCaps.DistCaps value;\n // constructors\n public DistCapsHolder() {\n this(null);\n }\n public DistCapsHolder(DistributedCaps.DistCaps __arg) {\n value = __arg;\n }\n\n public void _write(org.omg.CORBA.portable.OutputStream out) {\n DistributedCaps.DistCapsHelper.write(out, value);\n }\n\n public void _read(org.omg.CORBA.portable.InputStream in) {\n value = DistributedCaps.DistCapsHelper.read(in);\n }\n\n public org.omg.CORBA.TypeCode _type() {\nreturn DistributedCaps.DistCapsHelper.type();\nDistributedCaps\n\nInterface DistCaps\n\nAll Known Implementing Classes:\n_DistCapsImplBase, _DistCapsStub\n\npublic interface DistCaps\nextends org.omg.CORBA.Object, org.omg.CORBA.portable.IDLEntity\n\nMethod Summary\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Parameters</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>commit</td>\n<td>byte[] psdl_file, java.lang.String name, java.lang.String version, java.lang.String user</td>\n</tr>\n<tr>\n<td>get_proto_list</td>\n<td>java.lang.String user</td>\n</tr>\n<tr>\n<td>open_proto</td>\n<td>java.lang.String name, java.lang.String user</td>\n</tr>\n<tr>\n<td>translate</td>\n<td>byte[] psdl_file, java.lang.String name, java.lang.String version, java.lang.String user</td>\n</tr>\n</tbody>\n</table>\n\nMethods inherited from interface org.omg.CORBA.Object\n\n_create_request, _create_request, _duplicate, _get_domain_managers,\n_get_interface_def, _get_policy, _hash, _is_a, _is_equivalent, _non_existent,\n_release, _request, _set_policy_override\n\nMethod Detail\n\ntranslate\n\npublic java.lang.String translate(byte[] psdl_file,\njava.lang.String name,\njava.lang.String version,\njava.lang.String user)\nthrows DistributedCaps.DistCapsPackage.cantWriteFile\nget_proto_list\n\npublic java.lang.String[] get_proto_list(java.lang.String user)\n\n---\n\nopen_proto\n\npublic byte[] open_proto(java.lang.String name,\n java.lang.String user)\n throws DistributedCaps.DistCapsPackage.cantReadFile\n\n---\n\ncommit\n\npublic java.lang.String commit(byte[] psdl_file,\n java.lang.String name,\n java.lang.String version,\n java.lang.String user)\n throws DistributedCaps.DistCapsPackage.cantWriteFile\n### Constructor Summary\n\n- `DistCapsImplBase()`\n\n### Method Summary\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Signature</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>ids()</code></td>\n<td><code>java.lang.String[]</code></td>\n</tr>\n<tr>\n<td><code>invoke()</code></td>\n<td><code>void invoke(org.omg.CORBA.ServerRequest r)</code></td>\n</tr>\n</tbody>\n</table>\n\n### Methods inherited from class `org.omg.CORBA.portable.ObjectImpl`\n\n- `_create_request`, `_create_request`, `_duplicate`, `_get_delegate`, `_get_domain_managers`, `_get_interface_def`, `_get_policy`, `Hash`, `invoke`, `is_a`, `is_equivalent`, `is_local`, `non_existent`, `_orb`, `_release`, `_releaseReply`, `_request`, `_request`, `_servant_postinvoke`, `_servant_preinvoke`, `_set_delegate`, `_set_policy_override`, `equals`, `HashCode`, `toString`\n\n### Methods inherited from class `java.lang.Object`\n\n- `clone`, `finalize`, `getClass`, `notify`, `notifyAll`, `wait`, `wait`, `wait`\nConstructor Detail\n\n_DistCapsImplBase\n\npublic _DistCapsImplBase()\n\nMethod Detail\n\n_ids\n\npublic java.lang.String[] _ids()\n\nOverrides:\n_ids in class org.omg.CORBA.portable.ObjectImpl\n\ninvoke\n\npublic void invoke(org.omg.CORBA.ServerRequest r)\n\nOverrides:\ninvoke in class org.omg.CORBA.DynamicImplementation\nDistributedCaps\n\nClass _DistCapsStub\n\njava.lang.Object\n |\n ---org.omg.CORBA.portable.ObjectImpl\n |\n ---DistributedCaps._DistCapsStub\n\npublic class _DistCapsStub\nextends org.omg.CORBA.portable.ObjectImpl\nimplements DistCaps\n\nSee Also:\n Serialized Form\n\nConstructor Summary\n\n_DistCapsStub(org.omg.CORBA.portable.Delegate d)\n\nMethod Summary\n\n<table>\n<thead>\n<tr>\n<th>java.lang.String[]</th>\n<th>ids()</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>java.lang.String[]</td>\n<td>get_proto_list(java.lang.String user)</td>\n</tr>\n<tr>\n<td>byte[]</td>\n<td>open_proto(java.lang.String name, java.lang.String user)</td>\n</tr>\n</tbody>\n</table>\nMethods inherited from class org.omg.CORBA.portable.ObjectImpl\n\n_create_request, _create_request, duplicate, get_delegate,\n_get_domain_managers, _get_interface_def, _get_policy, _hash, _invoke, _is_a,\n_is_equivalent, _is_local, _non_existent, _orb, _release, _releaseReply,\n_request, _request, _servant_postinvoke, _servant_preinvoke, _set_delegate,\n_set_policy_override, equals, hashCode, toString\n\nMethods inherited from class java.lang.Object\n\nclose, finalize, getClass, notify, notifyAll, wait, wait, wait\n\nConstructor Detail\n\n_DistCapsStub\n\nclass public _DistCapsStub(org.omg.CORBA.portable.Delegate d)\n\nMethod Detail\n\n_ids\n\nclass public java.lang.String[] _ids()\n\nOverrides:\n_ids in class org.omg.CORBA.portable.ObjectImpl\n\ntranslate\n\nclass public java.lang.String translate(byte[] psdl_file,\njava.lang.String name,\njava.lang.String version,\njava.lang.String user)\nthrows DistributedCaps.DistCapsPackage.cantWriteFile\n\nSpecified by:\ntranslate in interface DistCaps\n\nget_proto_list\n\nclass public java.lang.String[] get_proto_list(java.lang.String user)\n\nSpecified by:\nget_proto_list in interface DistCaps\nopen_proto\n\npublic byte[] open_proto(java.lang.String name,\n java.lang.String user)\n throws DistributedCaps.DistCapsPackage.cantReadFile\n\nSpecified by:\n open_proto in interface DistCaps\n\ncommit\n\npublic java.lang.String commit(byte[] psdl_file,\n java.lang.String name,\n java.lang.String version,\n java.lang.String user)\n throws DistributedCaps.DistCapsPackage.cantWriteFile\n\nSpecified by:\n commit in interface DistCaps\nDistributedCaps\n\nClass DistCapsHelper\n\njava.lang.Object\n|-- DistributedCaps.DistCapsHelper\n\npublic class DistCapsHelper\nextends java.lang.Object\n\n### Method Summary\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>static DistCaps extract(org.omg.CORBA.Any a)</td>\n<td></td>\n</tr>\n<tr>\n<td>static java.lang.String id()</td>\n<td></td>\n</tr>\n<tr>\n<td>static void insert(org.omg.CORBA.Any a, DistCaps that)</td>\n<td></td>\n</tr>\n<tr>\n<td>static DistCaps narrow(org.omg.CORBA.Object that)</td>\n<td></td>\n</tr>\n<tr>\n<td>static DistCaps read(org.omg.CORBA.portable.InputStream in)</td>\n<td></td>\n</tr>\n<tr>\n<td>static org.omg.CORBA.TypeCode type()</td>\n<td></td>\n</tr>\n<tr>\n<td>static void write(org.omg.CORBA.portable.OutputStream out, DistCaps that)</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nMethods inherited from class java.lang.Object\n\nclass, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait\n\n### Method Detail\n\nwrite\npublic static void write(org.omg.CORBA.portable.OutputStream out,\n DistCaps that)\n\nread\n\npublic static DistCaps read(org.omg.CORBA.portable.InputStream in)\n\nextract\n\npublic static DistCaps extract(org.omg.CORBA.Any a)\n\ninsert\n\npublic static void insert(org.omg.CORBA.Any a,\n DistCaps that)\n\ntype\n\npublic static org.omg.CORBA.TypeCode type()\n\nid\n\npublic static java.lang.String id()\n\nnarrow\n\npublic static DistCaps narrow(org.omg.CORBA.Object that)\n throws org.omg.CORBA.BAD_PARAM\n\n<table>\n<thead>\n<tr>\n<th>Class</th>\n<th>Tree</th>\n<th>Deprecated</th>\n<th>Index</th>\n<th>Help</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nPREV CLASS | NEXT CLASS\nSUMMARY: INNER | FIELD | CONSTR | METHOD\n\nFRAMES | NO FRAMES\nDETAIL: FIELD | CONSTR | METHOD\n\n121\nClass DistCapsHolder\n\ndistributedCaps\n\njava.lang.Object\n +--DistributedCaps.DistCapsHolder\n\npublic final class DistCapsHolder\nextends java.lang.Object\nimplements org.omg.CORBA.portable.Streamable\n\nField Summary\nDistCaps value\n\nConstructor Summary\nDistCapsHolder()\nDistCapsHolder(DistCaps _arg)\n\nMethod Summary\nvoid read(org.omg.CORBA.portable.InputStream in)\norg.omg.CORBA.TypeCode type()\nvoid write(org.omg.CORBA.portable.OutputStream out)\n\nMethods inherited from class java.lang.Object\nclone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait\nField Detail\n\nvalue\n\npublic DistCaps value\n\nConstructor Detail\n\nDistCapsHolder\n\npublic DistCapsHolder()\n\nDistCapsHolder\n\npublic DistCapsHolder(DistCaps __arg)\n\nMethod Detail\n\n_write\n\npublic void _write(org.omg.CORBA.portable.OutputStream out)\n\nSpecified by:\n_write in interface org.omg.CORBA.portable.Streamable\n\n_read\n\npublic void _read(org.omg.CORBA.portable.InputStream in)\n\nSpecified by:\n_read in interface org.omg.CORBA.portable.Streamable\n\n_type\n\npublic org.omg.CORBA.TypeCode _type()\n\nSpecified by:\n_type in interface org.omg.CORBA.portable.Streamable\nAPPENDIX D: MODIFIED HSI SOURCE CODE\n\nThis appendix contains the HSI source files that were modified from [DURA99] and the corresponding Javadoc generated documentation. Changes from the original source code are bolded.\n\n```java\n/**\n * The main CAPS window.\n *\n * @author Ilker DURANLIOGLU, modified by Gary Kreeger\n * @version 1.1\n */\n\npackage caps.CAPSMain;\n\nimport java.awt.*;\nimport javax.swing.*;\nimport java.io.File;\nimport caps.Builder.PsdlBuilder;\nimport caps.Psdl.Vertex;\nimport caps.Psdl.DataTypes;\nimport caps.GraphEditor.Editor;\nimport java.awt.event.*;\nimport java.util.Vector;\nimport java.util Enumeration;\nimport DistributedCaps.*;\n\npublic class CAPSMainWindow extends JFrame {\n\n/**\n * The width of the frame.\n */\n\nprivate final int WIDTH = 400;\n\n/**\n * The height of the frame.\n */\n\nprivate final int HEIGHT = 150;\n\n/**\n * The File that contains the PSDL prototype.\n */\n\nprivate File prototype;\n```\n/**\n * The object reference to the CAPS server.\n */\n\nprivate DistCaps capsRef;\n\n/**\n * The Vector that holds references to the open prototypes\n */\n\nprivate static Vector openPrototypes;\n\n//THE FOLLOWING ATTRIBUTES WERE SUGGESTED BY PROFESSOR SHING\n\n/**\n * The private attribute for holding protoName.\n */\n\nprivate static String protoName;\n\n/**\n * The private attribute for holding protoVersion.\n */\n\nprivate static String protoVersion;\n\n/**\n * The private attribute for holding capsUser.\n */\n\nprivate static String capsUser;\n\n/**\n * The constructor for this class.\n *\n * @param objRef The reference to the CAPS object on the server\n */\n\npublic CAPSMainWindow (DistCaps objRef)\n{\n super (\"HSI Designer Mode\"); // The title of the frame.\n\n prototype = null;\n\n capsRef = objRef; //reference to server object\n\n capsUser = System.getProperty(\"CAPSUser\"); // session user\n\n openPrototypes = new Vector (0, 2);\ninitialize ();\n\n/**\n * Initializes the CAPS main window.\n */\n\npublic void initialize ()\n{\n setDefaultCloseOperation(WindowConstants.DO NOTHING_ON_CLOSE);\n addWindowListener (new ExitCAPSMain (this));\n\n // Places the frame in the upper-right corner of the screen\n Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();\n setLocation(screenSize.width - (WIDTH + WIDTH / 2), HEIGHT / 2);\n\n setResizable (false);\n\n setJMenuBar (new CAPSMainMenuBar (this));\n\n JPanel panel = new JPanel ();\n\n JLabel capsLabel = new JLabel (\"Heterogeneous System Integrator\");\n capsLabel.setFont (new Font (\"Courier\", Font.BOLD, 17));\n JLabel imageLabel = new JLabel (new ImageIcon (\"caps/Images/caps.gif\"));\n\n panel.add (Box.createHorizontalStrut (5));\n panel.add (imageLabel);\n panel.add (Box.createHorizontalStrut (5));\n panel.add (capsLabel);\n panel.add (Box.createHorizontalStrut (5));\n\n getContentPane ().add (panel);\n\n pack ();\n\n setVisible (true);\n}\n\n/**\n * Sets the prototype file to the argument.\n * @param f The File that contains the PSDL prototype.\n */\n\npublic void setPrototype (File f)\n{\n prototype = f;\n}\n/**\n * Sets the label to the string message passed in.\n * @param msg The message to be displayed.\n */\n\npublic void setLabel (String msg) {\n JOptionPane.showMessageDialog (this, msg, \"Information Message\",\n JOptionPane.INFORMATION_MESSAGE);\n}\n\n/**\n * Retrieves the current prototype file.\n * @return the File that contains the PSDL prototype.\n */\n\npublic File getPrototype () {\n return prototype;\n}\n\n/**\n * Retrieves the current reference to the caps server.\n * @return the reference to the caps server object.\n */\n\npublic DistCaps getCapsRef () {\n return capsRef;\n}\n\n/**\n * Returns the vector that holds the open prototype files.\n * @return the vector that contains the open prototype files.\n */\n\npublic Vector getOpenPrototypes () {\n return openPrototypes;\n}\n\n/**\n * Sets the prototype name to the argument\n * @param name The string that contains the prototype's name\n */\n\npublic void setProtoName (String name)\n{\n protoName = name;\n}\n\n/**\n * Sets the prototype version to the argument\n * @param version The string that contains the prototype's version\n */\npublic void setProtoVersion (String version)\n{\n protoVersion = version;\n}\n\n/**\n * Gets the prototype name\n */\npublic String getProtoName ()\n{\n return protoName;\n}\n\n/**\n * Gets the prototype version\n */\npublic String getProtoVersion ()\n{\n return protoVersion;\n}\n\n/**\n * Gets the capsUser\n */\npublic String getCapsUser ()\n{\n return capsUser;\n}\n\n/**\n * Opens the graphics editor to edit a prototype.\n */\npublic void editPrototype ()\n{\n if (prototype == null) { // No prototype is selected to open\n JOptionPane.showMessageDialog(this, \"No prototype is selected to edit.\",\n\n\"Error Message\", JOptionPane.ERROR_MESSAGE);\n\nelse if (isPrototypeChanged ()) { // Attempt to edit the same prototype.\n JOptionPane.showMessageDialog (this, new String (\"Prototype \" + prototype.getName () + \n \" is already open.\"), \n \"Error Message\", JOptionPane.ERROR_MESSAGE);\n\n} else {\n PSDLBuilder.disable_tracing (); // Disable debug messages\n Vertex root = null;\n root = PSDLBuilder.buildPrototype (prototype);\n if (root == null) {\n root = new Vertex (0, 0, null, false); // If this is a new prototype\n String name = prototype.getName (); // Prototype name is the same as\n root.setLabel (name.substring (0, name.length () - 5)); // the file name\n }\n DataTypes types = new DataTypes ();\n types.buildTypes (prototype);\n Editor e = new Editor (prototype, root, types);\n new Thread (e).start ();\n openPrototypes.addElement (e);\n}\n\n/**\n * Checks whether or not the current prototype file is already used by\n * a PSDL Editor.\n *\n * @return true if selected prototype is not already open\n *\n */\n\npublic boolean isPrototypeChanged ()\n{\n for (Enumeration enum = openPrototypes.elements (); enum.hasMoreElements ();) {\n Editor e = (Editor) enum.nextElement ();\n if (prototype.equals (e.getPrototypeFile ()))\n return false;\n }\n return true;\n}\n\n/**\n * Removes one element from the openPrototypes vector.\n *\n * @param e the editor that is going to be removed from the vector.\n *\n */\n\npublic static void removeEditor (Editor e)\n{\n openPrototypes.removeElement (e);\n}\n\n/**\n* Checks if the status of any of the open prototypes is 'saveRequired'.\n* Prompts the user to save the prototype.\n*\n* @return true if none of the prototypes need saving.\n*/\n\npublic boolean isOpenPrototypeSaved ()\n{\n boolean flag = true;\n Editor e;\n label :\n for (Enumeration enum = openPrototypes.elements (); enum.hasMoreElements ();)\n {\n e = (Editor) enum.nextElement ();\n if (e.isSaveRequired () )\n {\n int ix = JOptionPane.showConfirmDialog (this, new String (\"Save changes to the prototype \" + \n e.getRoot ().getLabel () + \"?\");\n if (ix == JOptionPane.CANCEL_OPTION)\n {\n flag = false;\n break label;\n }\n else if (ix == JOptionPane.YES_OPTION)\n e.savePrototype ();\n }\n }\n return flag;\n}\n\n} // End of the class CAPSMainWindow\n\n/**\n * This class holds the 'Exec Support' menu items.\n * *\n * @author Ilker DURANLIOGLU, modified by Gary Kreeger\n * *\n * @version 1.1\n */\n\npackage caps.CAPSMain;\n\nimport javax.swing.JMenu;\nimport javax.swing.JMenuItem;\nimport java.awt.event.ActionEvent;\nimport java.awt.event.ActionListener;\nimport java.awt.*;\nimport java.io.IOException;\nimport javax.swing.*;\nimport java.io.*;\nimport DistributedCaps.*;\n\npublic class ExecSupportMenu extends JMenu implements ActionListener {\n\n /**\n * Initiates the 'Translate' event\n */\n private JMenuItem translateMenuItem = new JMenuItem(\"Translate\");\n/**\n * Initiates the 'Schedule' event\n */\nprivate JMenuItem scheduleMenuItem = new JMenuItem(\"Schedule\");\n\n/**\n * Initiates the 'Compile' event\n */\nprivate JMenuItem compileMenuItem = new JMenuItem(\"Compile\");\n\n/**\n * Initiates the 'Execute' event\n */\nprivate JMenuItem executeMenuItem = new JMenuItem(\"Execute\");\n\n/**\n * The main window which owns this menu.\n */\nprotected CAPSMainWindow ownerWindow;\n\n/**\n * Constructor for this class.\n *\n * @param owner CAPSMainWindow that owns the menu\n */\npublic ExecSupportMenu (CAPSMainWindow owner)\n{\n super (\"Exec Support\");\n\n ownerWindow = owner;\n\n add (translateMenuItem);\n add (scheduleMenuItem);\n add (compileMenuItem);\n add (executeMenuItem);\n\n // Register the action listeners\n translateMenuItem.addActionListener (this);\n scheduleMenuItem.addActionListener (this);\n compileMenuItem.addActionListener (this);\n executeMenuItem.addActionListener (this);\n}\n// end of ExecSupportMenu constructor\n\n/**\n * Action event handler for the menu events.\n *\n * @param e The action event that is created by selecting a menu item\n */\npublic void actionPerformed(ActionEvent e)\n{\n\nif (e.getSource () == translateMenuItem) {\n\n if (ownerWindow.getPrototype () == null) // No prototype is selected to open\n {\n JOptionPane.showMessageDialog (ownerWindow,\n \"No prototype is selected to edit.\", \"Error Message\", JOptionPane.ERROR_MESSAGE);\n }\n else\n {\n try\n {\n File proto = ownerWindow.getPrototype ();\n\n FileInputStream in = new FileInputStream (proto);\n byte[] fileBuf = new byte [in.available ()];\n in.read (fileBuf);\n\n DistCaps capsRef = ownerWindow.getCapsRef ();\n\n String returnMsg = capsRef.translate (fileBuf, ownerWindow.getProtoName (),\n ownerWindow.getProtoVersion (), ownerWindow.getCapsUser ());\n\n ownerWindow.setLabel (returnMsg);\n System.out.println (returnMsg);\n }\n catch (Exception e1)\n {\n System.err.println (\"Error: \" + e1);\n e1.printStackTrace (System.out);\n }\n }\n}\nelse if (e.getSource () == scheduleMenuItem) {\n System.out.println (\"Schedule has not been implemented yet\");\n}\nelse if (e.getSource () == compileMenuItem) {\n System.out.println (\"Compile has not been implemented yet\");\n}\nelse if (e.getSource () == executeMenuItem) {\n System.out.println (\"Executing telnet\");\n try {\n Runtime run = Runtime.getRuntime ();\n run.exec (\"telnet.exe\");\n } catch (IOException ex) {\n System.out.println (ex);\n }\n}\n} // end of actionPerformed\n\n} // End of the class ExecSupportMenu\n/**\n * This class holds the 'Prototype' menu items.\n * \n * @author Ilker DURANLIOGLU, modified by Gary Kreeger\n * \n * @version 1.1\n */\n\npackage caps.CAPSMain;\n\nimport javax.swing.*;\nimport javax.swing.filechooser.FileSystemView;\nimport java.awt.*;\nimport java.awt.event.ActionEvent;\nimport java.awt.event.ActionListener;\nimport java.io.File;\nimport java.io.*;\nimport java.util.Vector;\nimport DistributedCaps.*;\n\npublic class PrototypeMenu extends JMenu implements ActionListener {\n\n /**\n * Initiates the 'New' event\n */\n\n private JMenuItem newItem = new JMenuItem(\"New\");\n\n /**\n * Initiates the 'Open' event\n */\n\n private JMenuItem openMenuItem = new JMenuItem(\"Open\");\n\n /**\n * Initiates the 'Commit Work' event\n */\n\n private JMenuItem commitWorkMenuItem = new JMenuItem(\"Commit Work\");\n\n /**\n * Initiates the 'Retrieve From DDB' event\n */\n\n private JMenuItem retrieveMenuItem = new JMenuItem(\"Retrieve From DDB\");\n\n /**\n * Initiates the 'Quit' event\n */\n\n private JMenuItem quitMenuItem = new JMenuItem(\"Quit\");\n\n}\n/**\n * The main window which owns this menu.\n */\n\nprotected CAPSMainWindow ownerWindow;\n\n/**\n * Constructor for this class.\n *\n * @param owner The main window which has created this menu.\n */\n\npublic PrototypeMenu (CAPSMainWindow owner)\n{\n super (\"Prototype\");\n\n ownerWindow = owner;\n\n add (newMenuItem);\n add (openMenuItem);\n add (commitWorkMenuItem);\n add (retrieveMenuItem);\n add (quitMenuItem);\n\n //Register the action listeners\n\n newItem.addActionListener (this);\n openItem.addActionListener (this);\n commitWorkItem.addActionListener (this);\n retrieveItem.addActionListener (this);\n quitItem.addActionListener (this);\n} // end PrototypeMenu constructor\n\n/**\n * Action event handler for the menu events.\n *\n * @param e The action event that is created by selecting a menu item from this menu\n */\n\npublic void actionPerformed(ActionEvent e)\n{\n if (e.getSource () == newItem) {\n processNewItem ();\n }\n else if (e.getSource () == openItem) {\n processOpenItem ();\n }\n else if (e.getSource () == commitWorkItem) {\n processCommitWorkItem();\n }\n else if (e.getSource () == retrieveItem) {\n System.out.println (\"Retrieve has not yet been implemented\");\n }\n} else if (e.getSource () == quitMenuItem) {\n // Exit the program if all of the prototypes are saved.\n if (ownerWindow.isOpenPrototypeSaved ())\n System.exit (0);\n}\n\n//end of actionPerformed\n\n/**\n * Handles the event which is caused by selecting the 'New' menu item.\n */\n\npublic void processNewItem ()\n{\n // The system property for the home prototype directory.\n String protoHome = System.getProperty (\"PROTOTYPEHOME\");\n File protoDir;\n if (protoHome == null) {\n // If it is not set as a command line argument\n File homeDir = FileSystemView.getFileSystemView ().getHomeDirectory ();\n protoHome = new String (homeDir + File.separator + \".caps\");\n protoDir = new File (protoHome);\n if (!protoDir.exists ())\n protoDir.mkdir ();\n } else {\n protoDir = new File (protoHome);\n if (!protoDir.exists ())\n protoDir.mkdir ();\n }\n\n String proto = JOptionPane.showInputDialog (ownerWindow,\n \"Enter Prototype Name : \", \"New\", JOptionPane.PLAIN_MESSAGE);\n if (proto == null)\n return;\n\n String version = JOptionPane.showInputDialog (ownerWindow,\n \"Prototype Version Information : \", \"New\", JOptionPane.PLAIN_MESSAGE);\n\n String name = proto;\n\n File file = new File (protoHome + File.separator + proto + File.separator + version +\n File.separator + name + \".psdl\");\n if (file.exists ()) {\n int selected = JOptionPane.showConfirmDialog (ownerWindow, \"Selected prototype file already exists.\\n\" +\n \"Do you want to overwrite it?\");\n if (selected == JOptionPane.YES_OPTION) {\n try {\n file.delete ();\n file.createNewFile ();\n } catch (java.io.IOException ex) {\n System.out.println (ex);\n }\n ownerWindow.setPrototype (file);\n }\n }\nelse {\n try {\n File dir = file.getParentFile ().getParentFile ();\n dir.mkdir ();\n File vers = file.getParentFile ();\n vers.mkdir ();\n file.createNewFile ();\n } catch (java.io.IOException ex) {\n System.out.println (ex);\n }\n ownerWindow.setPrototype (file);\n ownerWindow.setProtoName (proto);\n ownerWindow.setProtoVersion (version);\n}\n}\n} // end of processNewItem\n\n/**\n * Handles the event which is caused by selecting the 'Open' menu item.\n */\n\npublic void processOpenMenuItem ()\n{\n Object[] possibleValues = { \"Local\", \"Remote\"};\n String selectedValue = (String) JOptionPane.showInputDialog(null,\n \"Please choose the prototype source\", \"Input\",\n JOptionPane.INFORMATION_MESSAGE, null, possibleValues, possibleValues[0]);\n\n if (selectedValue == \"Local\")\n {\n String protoHome = System.getProperty (\"PROTOTYPEHOME\");\n File protoDir;\n if (protoHome == null) // If it is not set as a command line argument\n {\n File homeDir = FileSystemView.getFileSystemView ().getHomeDirectory ();\n protoHome = new String (homeDir + File.separator + \".caps\");\n protoDir = new File (protoHome);\n if (!protoDir.exists ())\n {\n protoDir.mkdir ();\n }\n } else\n {\n protoDir = new File (protoHome);\n if (!protoDir.exists ())\n protoDir.mkdir ();\n }\n\n Vector prototypeNames = new Vector (0, 2);\n File [] dirs = protoDir.listFiles ();\n String protoName = \"\";\n\n if (dirs.length == 0)\n {\n }\n }\n}\nJOptionPane.showMessageDialog(ownwerWindow, \"No prototype is is found to open\", \"Error Message\", JOptionPane.ERROR_MESSAGE);\n\nelse\n{\n for (int ix = 0; ix < dirs.length; ix++)\n {\n protoName = dirs[ix].getName();\n File subDirs [] = dirs [ix].listFiles ();\n for (int jx = 0; jx < subDirs.length; jx++)\n {\n prototypeNames.addElement (protoName.concat\n (File.separator + subDirs [jx].getName ());\n }\n }\n}\n\nObject [] protos = prototypeNames.toArray ();\nString selected = (String) JOptionPane.showInputDialog (ownerWindow, \"Select a prototype :\", \"Open\", JOptionPane.INFORMATION_MESSAGE, null, protos, protos [0]);\n\nif (selected != null)\n{\n File selectedDir = new File (protoHome + File.separator + selected);\n File file = new File (selectedDir.getAbsolutePath () + File.separator +\n selectedDir.getParentFile ().getName () + \".psdl\");\n if (!file.exists ())\n {\n JOptionPane.showMessageDialog (ownerWindow,\n \"The selected prototype file cannot be opened\",\n \"Error Message\", JOptionPane.ERROR_MESSAGE);\n }\n ownerWindow.setPrototype (file);\n ownerWindow.setProtoName (selectedDir.getParentFile ().getName ());\n ownerWindow.setProtoVersion (selectedDir.getName ());\n}\nelse // open prototype from remote source\n{\n DistCaps capsRef = ownerWindow.getCapsRef();\n\n //get the list of available prototypes\n String [] proto_list = capsRef.get_proto_list(ownerWindow.getCapsUser());\n\n byte[] proto_file;\n String selected = (String) JOptionPane.showInputDialog (ownerWindow, \"Select a prototype :\", \"Open\",\n JOptionPane.INFORMATION_MESSAGE, null, proto_list, proto_list [0]);\n\n try\n {\n //open the selected file from the remote server\n proto_file = capsRef.open_proto (selected, ownerWindow.getCapsUser());\n\n if (proto_file == null)\n{ \n JOptionPane.showMessageDialog(ownerWindow,\n \"The selected prototype file cannot be opened\",\n \"Error Message\", JOptionPane.ERROR_MESSAGE);\n}\nelse\n{\n try //convert the selected file from a byte array back to a file\n {\n String protoHome = System.getProperty(\"PROTOTYPEHOME\");\n File protoDir;\n if (protoHome == null) // If it is not set as a command line argument\n {\n File homeDir = FileSystemView.getFileSystemView().getHomeDirectory();\n protoHome = new String(homeDir + File.separator + \".caps\");\n protoDir = new File(protoHome);\n if (!protoDir.exists())\n {\n protoDir.mkdirs();\n }\n }\n else\n {\n protoDir = new File(protoHome);\n if (!protoDir.exists())\n {\n protoDir.mkdirs();\n }\n }\n }\n File selectedDir = new File(protoHome + File.separator + selected);\n if (!selectedDir.exists())\n {\n selectedDir.mkdirs();\n }\n else\n {\n ownerWindow.setLabel(\"The remote file will overwrite an existing local one\");\n }\n File file = new File(selectedDir.getAbsolutePath() + File.separator + \".psdl\");\n boolean tempBoolean = file.createNewFile();\n FileOutputStream fos = new FileOutputStream(file);\n fos.write(proto_file);\n fos.close();\n ownerWindow.setPrototype(file);\n ownerWindow.setProtoName(selectedDir.getParentFile().getName());\n ownerWindow.setProtoVersion(selectedDir.getName());\n}\ncatch (Exception e)\n{\n JOptionPane.showMessageDialog(ownerWindow,\n \"The selected prototype file was retrieved but cannot be opened\",\n \"Error Message\", JOptionPane.ERROR_MESSAGE);\n}\nSystem.out.println (e);\n}\n}\n\ncatch (DistributedCaps.DistCapsPackage.cantReadFile e2)\n{\n JOptionPane.showMessageDialog (ownerWindow,\n \"The selected prototype file cannot be opened\",\n \"Error Message\", JOptionPane.ERROR_MESSAGE);\n System.out.println (e2);\n}\n\n//End of processOpenMenuItem\n\n/**\n * Handles the event which is caused by selecting the 'Commit' menu item.\n */\n\npublic void processCommitWorkMenuItem ()\n{\n setCursor (new Cursor(Cursor.WAIT_CURSOR));\n File proto = ownerWindow.getPrototype();\n String protoName = ownerWindow.getProtoName();\n\n if ( protoName == null) // No prototype is selected to open\n {\n JOptionPane.showMessageDialog (ownerWindow,\n \"No prototype is selected.\", \"Error Message\", JOptionPane.ERROR_MESSAGE);\n }\n else\n {\n if (ownerWindow.isOpenPrototypeSaved ()\n {\n try //convert the file to a byte array for transfer to the server\n {\n FileInputStream in = new FileInputStream (proto);\n byte[] fileBuf = new byte[in.available()];\n in.read (fileBuf);\n\n DistCaps capsRef = ownerWindow.getCapsRef();\n\n String returnMsg = capsRef.commit(fileBuf, protoName,\n ownerWindow.getProtoVersion(), ownerWindow.getCapsUser());\n\n ownerWindow.setLabel (returnMsg);\n System.out.println (returnMsg);\n\n }\n catch (Exception e1)\n {\n System.err.println (\"Error: \" + e1);\n e1.printStackTrace (System.out);\n }\n }\n }\n}\n{ \n ownerWindow.setLabel(\"You must save the prototype before committing it\");\n}\n\nsetCursor(new Cursor(Cursor.DEFAULT_CURSOR));\n\n} //end of processCommitWorkMenuItem\n\n} // End of the class PrototypeMenu\ncaps.CAPSMain\n\nClass CAPSMainWindow\n\njava.lang.Object\n | +---java.awt.Component\n | | +---java.awt.Container\n | | | +---java.awt.Window\n | | | | +---java.awt.Frame\n | | | | | +---javax.swing.JFrame\n | | | | | | +---caps.CAPSMain.CAPSMainWindow\n\npublic class CAPSMainWindow\nextends javax.swing.JFrame\n\nThe main CAPS window.\n\nSee Also:\n Serialized Form\n\nInner classes inherited from class javax.swing.JFrame\njavax.swing.JFrame.Accessible(JFrame\n\nInner classes inherited from class java.awt.Component\njava.awt.Component.AWTTreeLock\n### Field Summary\n\n<table>\n<thead>\n<tr>\n<th>Private Variable</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>capsRef</code></td>\n<td>The object reference to the CAPS server.</td>\n</tr>\n<tr>\n<td><code>capsUser</code></td>\n<td>The private attribute for holding capsUser.</td>\n</tr>\n<tr>\n<td><code>HEIGHT</code></td>\n<td>The height of the frame.</td>\n</tr>\n<tr>\n<td><code>openPrototypes</code></td>\n<td>The Vector that holds references to the open prototypes</td>\n</tr>\n<tr>\n<td><code>protoName</code></td>\n<td>The private attribute for holding protoName.</td>\n</tr>\n<tr>\n<td><code>prototype</code></td>\n<td>The File that contains the PSDL prototype.</td>\n</tr>\n<tr>\n<td><code>protoVersion</code></td>\n<td>The private attribute for holding protoVersion.</td>\n</tr>\n<tr>\n<td><code>WIDTH</code></td>\n<td>The width of the frame.</td>\n</tr>\n</tbody>\n</table>\n\n### Fields inherited from class `javax.swing.JFrame`\n\n`accessibleContext, defaultCloseOperation, rootPane, rootPaneCheckingEnabled`\n\n### Fields inherited from class `java.awt.Frame`\n\n`base, CROSSHAIR_CURSOR, DEFAULT_CURSOR, E_RESIZE_CURSOR, frameSerializedDataVersion, HAND_CURSOR, icon, ICONIFIED, mbManagement, menuBar, MOVE_CURSOR, N_RESIZE_CURSOR, nameCounter, NE_RESIZE_CURSOR, NORMAL, NW_RESIZE_CURSOR, ownedWindows, resizable, S_RESIZE_CURSOR, SE_RESIZE_CURSOR, serialVersionUID, state, SW_RESIZE_CURSOR, TEXT_CURSOR, title, W_RESIZE_CURSOR, WAIT_CURSOR, weakThis`\n\n### Fields inherited from class `java.awt.Window`\n\n`active, base, focusMgr, inputContext, nameCounter, OPENED, ownedWindowList, serialVersionUID, state, warningString, weakThis, windowListener, windowSerializedDataVersion`\n\n### Fields inherited from class `java.awt.Container`\n\n`component, containerListener, containerSerializedDataVersion, dispatcher, layoutMgr, maxSize, ncomponents, serialVersionUID`\nFields inherited from class java.awt.Component\nactionListenerK, adjustmentListenerK, appContext, assert, background,\nBOTTOM_ALIGNMENT, CENTER_ALIGNMENT, changeSupport, componentListener,\ncomponentListenerK, componentOrientation, componentSerializedDataVersion,\ncontainerListenerK, cursor, dropTarget, enabled, eventMask, focusListener,\nfocusListenerK, font, foreground, hasFocus, height, incRate, inputMethodListener,\ninputMethodListenerK, isInc, ispacked, itemListenerK, keyListener, keyListenerK,\nLEFT_ALIGNMENT, locale, LOCK, minSize, mouseListener, mouseListenerK,\nmouseMotionListener, mouseMotionListenerK, name, nameExplicitlySet, newEventsOnly,\nownedWindowK, parent, peer, peerFont, popups, prefSize, RIGHT_ALIGNMENT,\nserialVersionUID, textListenerK, TOP_ALIGNMENT, valid, visible, width,\nwindowListenerK, x, y\n\nConstructor Summary\nCAPSMainwindow(DistributedCaps.DistCaps objRef)\nThe constructor for this class.\n\nMethod Summary\n\n<table>\n<thead>\n<tr>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>void editPrototype()</td>\n<td>Opens the graphics editor to edit a prototype.</td>\n</tr>\n<tr>\n<td>DistributedCaps.DistCaps</td>\n<td>getCapsRef()</td>\n</tr>\n<tr>\n<td>java.lang.String</td>\n<td>getCapsUser()</td>\n</tr>\n<tr>\n<td>java.util.Vector</td>\n<td>getOpenPrototypes()</td>\n</tr>\n<tr>\n<td>java.lang.String</td>\n<td>getProtoName()</td>\n</tr>\n<tr>\n<td>java.io.File</td>\n<td>getPrototype()</td>\n</tr>\n<tr>\n<td>java.lang.String</td>\n<td>getProtoVersion()</td>\n</tr>\n<tr>\n<td>void initialize()</td>\n<td>Initializes the CAPS main window.</td>\n</tr>\n<tr>\n<td>boolean isOpenPrototypeSaved()</td>\n<td>Checks if the status of any of the open prototypes is 'saveRequired'.</td>\n</tr>\n<tr>\n<td>boolean isPrototypeChanged()</td>\n<td>Checks whether or not the current prototype file is already used by a</td>\n</tr>\n<tr>\n<td></td>\n<td>PSDL Editor.</td>\n</tr>\n<tr>\n<td>static void removeEditor(caps.GraphEditor.Editor e)</td>\n<td>Removes one element from the openPrototypes vector.</td>\n</tr>\n<tr>\n<td>void setLabel(java.lang.String msg)</td>\n<td>Sets the label to the string message passed in.</td>\n</tr>\n<tr>\n<td>void setProtoName(java.lang.String name)</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nSets the prototype name to the argument\n\n```java\nvoid setPrototype(java.io.File f)\n Sets the prototype file to the argument.\n```\n\nSets the prototype version to the argument\n\n```java\nvoid setProtoVersion(java.lang.String version)\n```\n\n### Methods inherited from class `javax.swing.JFrame`\n\n- addImpl, createRootPane, createRootPaneException, frameInit, getAccessibleContext, getContentType, getDefCloseOperation, getGlassPane, getJMenuBar, getLayeredPane, getRootPane, isRootPaneCheckEnabled, paramString, processKeyEvent, processWindowEvent, remove, setContentType, setDefCloseOperation, setGlassPane, setJMenuBar, setLayeredPane, setLayout, setRootPane, setRootPaneCheckEnabled, update\n\n### Methods inherited from class `java.awt.Frame`\n\n- addNotify, addToFrameList, constructComponentName, finalize, getCursorType, getFrames, getIconImage, getJMenuBar, getState, getTitle, initIDs, isResizable, postProcessKeyEvent, readObject, remove, removeFromFrameList, removeNotify, setSize, setIconImage, setJMenuBar, setSize, setResizable, setState, setTitle, writeObject\n\n### Methods inherited from class `java.awt.Window`\n\n- addOwnedWindow, addWindowListener, applyResourceBundle, applyResourceBundle, connectOwnedWindow, dispatchEventImpl, dispose, eventEnabled, getFocusOwner, getInContext, getLocale, getOwnedWindows, getOwner, getToolkit, getWarningString, hide, isActivate, isShowing, nextFocus, ownedInit, pack, postEvent, postWindowEvent, preProcessKeyEvent, processEvent, removeOwnedWindow, removeWindowListener, setSize, setFocusOwner, setWarningString, show, toBack, toFront, transferFocus\n\n### Methods inherited from class `java.awt.Container`\n\n- add, add, add, add, addContainerListener, applyOrientation, countComponents, deliverEvent, dispatchEventToSelf, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponent, getComponentAt, getComponentCount, getComponents_NoClientCode, getComponents, getCursorTarget, getInsets, getLayout, getMaximumSize, getMinimumSize, getMouseEventTarget, getPreferredSize, getWindow, insets, invalidate, invalidateTree, isAncestorOf, layout, lightweightPrint, list, list, locate, minimumSize, paint, paintComponents, postOldMouseEvents, preferredSize, print, printComponents, printOneComponent, processContainerEvent, proxyEnableEvents, proxyRequestFocus, remove, removeAll, removeContainerListener, setFont, updateCursor, validate, validateTree\nMethods inherited from class java.awt.Component\n\naction, add, addComponentListener, addFocusListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addPropertyChangeListener, addPropertyChangeListener, areInputMethodsEnabled, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, getBackground, getBounds, getBounds, getColorModel, getComponentOrientation, getCursor, getDropTarget, getFont, getFontMetrics, getForeground, getGraphics, getHeight, getIntrinsicCursor, getLocation, getLocation, getLocationOnScreen, getName, getNativeContainer, getParent, getParent, getPeer, getSize, getSize, getToolkitImpl, getTreeLock, getWidth, getWindowForObject, getX, getY, getFocus, handleEvent, hasFocus, imageUpdate, inside, isDisplayable, isDoubleBuffered, isEnabled, isEnabledImpl, isFocusTraversable, isLightweight, isOpaque, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processInputMethodEvent, processMouseEvent, processMouseMotionEvent, removeComponentListener, removeFocusListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, reshape, reshape, reshape, setBackstop, setBounds, setComponentOrientation, setDropTarget, setEnabled, setForeground, setLocale, setLocation, setLocation, setName, setSize, setSize, setSize, setVisible, show, setSize, toString, transferFocus\n\nMethods inherited from class java.lang.Object\n\nclon, equals, getClass, hashCode, notify, notifyAll, registerNatives, wait, wait, wait\n\nField Detail\n\nWIDTH\n\nprivate final int WIDTH\n\nThe width of the frame.\n\nHEIGHT\n\nprivate final int HEIGHT\n\nThe height of the frame.\n\nprototype\n\nprivate java.io.File prototype\n\nThe File that contains the PSDL prototype.\ncapsRef\n\nprivate DistributedCaps.DistCaps capsRef\n\nThe object reference to the CAPS server.\n\nprotoName\n\nprivate static java.lang.String protoName\n\nThe private attribute for holding protoName.\n\nprotoVersion\n\nprivate static java.lang.String protoVersion\n\nThe private attribute for holding protoVersion.\n\ncapsUser\n\nprivate static java.lang.String capsUser\n\nThe private attribute for holding capsUser.\n\nopenPrototypes\n\nprivate static java.util.Vector openPrototypes\n\nThe Vector that holds references to the open prototypes\n\n**Constructor Detail**\n\n**CAPSMainWindow**\n\npublic CAPSMainWindow(DistributedCaps.DistCaps objRef)\n\nThe constructor for this class.\n\n**Parameters:**\n\nobjRef - The reference to the CAPS object on the server\ninitialize\n\npublic void initialize()\n\nInitializes the CAPS main window.\n\nsetPrototype\n\npublic void setPrototype(java.io.File f)\n\nSets the prototype file to the argument.\nParameters:\nf - The File that contains the PSDL prototype.\n\nsetLabel\n\npublic void setLabel(java.lang.String msg)\n\nSets the label to the string message passed in.\nParameters:\nmsg - The message to be displayed.\n\ngetPrototype\n\npublic java.io.File getPrototype()\n\nRetrieves the current prototype file.\nReturns:\nthe File that contains the PSDL prototype.\n\ngetcapsRef\n\npublic DistributedCaps.DistCaps getCapsRef()\n\nRetrieves the current reference to the caps server.\nReturns:\nthe reference to the caps server object.\n\ngetOpenPrototypes\npublic java.util.Vector getOpenPrototypes()\n\nReturns the vector that holds the open prototype files.\n\nReturns:\nthe vector that contains the open prototype files.\n\n---\n\nsetProtoName\n\npublic void setProtoName(java.lang.String name)\n\nSets the prototype name to the argument\n\nParameters:\nname - The string that contains the prototype's name\n\n---\n\nsetProtoVersion\n\npublic void setProtoVersion(java.lang.String version)\n\nSets the prototype version to the argument\n\nParameters:\nversion - The string that contains the prototype's version\n\n---\n\ngetProtoName\n\npublic java.lang.String getProtoName()\n\n Gets the prototype name\n\n---\n\ngetProtoVersion\n\npublic java.lang.String getProtoVersion()\n\n Gets the prototype version\n\n---\n\ngetCapsUser\n\npublic java.lang.String getCapsUser()\n\n Gets the capsUser\neditPrototype\n\npublic void editPrototype()\n\n Opens the graphics editor to edit a prototype.\n\nisPrototypeChanged\n\npublic boolean isPrototypeChanged()\n\n Checks whether or not the current prototype file is already used by a PSDL Editor.\n Returns:\n true if selected prototype is not already open\n\nremoveEditor\n\npublic static void removeEditor(caps.GraphEditor.Editor e)\n\n Removes one element from the openPrototypes vector.\n Parameters:\n e - the editor that is going to be removed from the vector.\n\nisOpenPrototypeSaved\n\npublic boolean isOpenPrototypeSaved()\n\n Checks if the status of any of the open prototypes is 'saveRequired'. Prompts the user to save the prototype.\n Returns:\n true if none of the prototypes need saving.\ncaps.CAPSMain\n\n**Class ExecSupportMenu**\n\n```\njava.lang.Object\n | +--java.awt.Component\n | | +--java.awt.Container\n | | | +--javax.swing.JComponent\n | | | +--javax.swing.AbstractButton\n | | | +--javax.swing.JMenuItem\n | | | +--javax.swing.JMenu\n | | | +--caps.CAPSMain.ExecSupportMenu\n```\n\npublic class ExecSupportMenu\nextends javax.swing.JMenu\nimplements java.awt.event.ActionListener\n\nThis class holds the 'Exec Support' menu items.\n\n**See Also:**\n- Serialized Form\n\n**Inner classes inherited from class javax.swing.JMenuItem**\n- javax.swing.JMenuItem.Accessible JMenuItem\n\n**Inner classes inherited from class javax.swing.AbstractButton**\n- javax.swing.AbstractButton.Accessible AbstractButton\n### Inner classes inherited from class `javax.swing.JMenuItem`\n\n- `compileMenuItem` Initiates the 'Compile' event\n- `executeMenuItem` Initiates the 'Execute' event\n- `ownerWindow` The main window which owns this menu.\n- `scheduleMenuItem` Initiates the 'Schedule' event\n- `translateMenuItem` Initiates the 'Translate' event\n\n### Field Summary\n\n- `private javax.swing.JMenuItem compileMenuItem` Initiates the 'Compile' event\n- `private javax.swing.JMenuItem executeMenuItem` Initiates the 'Execute' event\n- `protected caps.CAPSMain.CAPSMainWindow ownerWindow` The main window which owns this menu.\n- `private javax.swing.JMenuItem scheduleMenuItem` Initiates the 'Schedule' event\n- `private javax.swing.JMenuItem translateMenuItem` Initiates the 'Translate' event\n\n### Fields inherited from class `javax.swing.JMenuItem`\n\n- `delay`, `listenerRegistry`, `menuChangeListener`, `menuEvent`, `popupListener`, `popupMenu`, `uiClassID`\n\n### Fields inherited from class `javax.swing.JMenuItem`:\n\n- `accelerator`, `uiClassID`\n\n### Fields inherited from class `javax.swing.A一听Button`\n\n- `actionListener`, `BORDER_PAINTED_CHANGED_PROPERTY`, `changeEvent`, `changeListener`, `CONTENT_AREA_FILLED_CHANGED_PROPERTY`, `contentAreaFilled`, `defaultIcon`, `defaultMargin`, `DISABLED_ICON_CHANGED_PROPERTY`, `DISABLED_SELECT_ICON_CHANGED_PROPERTY`, `disabledIcon`, `disabledSelectedIcon`, `FOCUS_PAINTED_CHANGED_PROPERTY`, `HORIZONTAL_ALIGNMENT_CHANGED_PROPERTY`, `HORIZONTAL_TEXT_POSITION_CHANGED_PROPERTY`, `horizontalAlignment`, `horizontalTextPosition`, `ICON_CHANGED_PROPERTY`, `itemListener`, `margin`, `MARGIN_CHANGED_PROPERTY`, `MNEMONIC_CHANGED_PROPERTY`, `model`, `MODEL_CHANGED_PROPERTY`, `paintBorder`, `paintFocus`, `PRESSED_ICON_CHANGED_PROPERTY`, `pressedIcon`, `ROLLOVER_ENABLED_CHANGED_PROPERTY`, `ROLLOVER_ICON_CHANGED_PROPERTY`, `ROLLOVER_SELECT_ICON_CHANGED_PROPERTY`, `rolloverEnabled`, `rolloverIcon`, `rolloverSelectedIcon`, `SELECTED_ICON_CHANGED_PROPERTY`, `selectedIndex`, `text`, `TEXT_CHANGED_PROPERTY`, `VERTICAL_ALIGNMENT_CHANGED_PROPERTY`, `verticalAlign`, `verticalTextPosition`\n### Fields inherited from class `javax.swing.JComponent`\n\n- bounds, accessibleContext, alignmentX, alignmentY, ANCESTOR_USING_BUFFER,\nancestorNotifier, autoscroll, border, changeSupport, clientProperties, flags,\nHAS_FOCUS, IS_DOUBLE_BUFFERED, IS_OPAQUE, IS_PAINTING_TILE, KEYBOARD_BINDINGS_KEY,\nlistenerList, maximumSize, minimumSize, NEXT_FOCUS, paintImmediatelyClip,\npaintingChild, preferredSize, readObjectCallBacks, REQUEST_FOCUS_DISABLED, tmpRect,\nTOOL_TIP_TEXT_KEY, ui, uiClassID, UNDEFINED_CONDITION, vetoableChangeSupport,\nWHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW\n\n### Fields inherited from class `java.awt.Container`\n\n- component, containerListener, containerSerializedDataVersion, dispatcher, layoutMgr,\nmaxSize, ncomponents, serialVersionUIDUID\n\n### Fields inherited from class `java.awt.Component`\n\n- actionListenerK, adjustmentListenerK, appContext, assert, background,\nBOTTOM_ALIGNMENT, CENTER_ALIGNMENT, changeSupport, componentListener,\ncomponentListenerK, componentOrientation, componentSerializedDataVersion,\ncontainerListenerK, cursor, dropTarget, enabled, eventMask, focusListener,\nfocusListenerK, font, foreground, hasFocus, height, incRate, inputMethodListener,\ninputMethodListenerK, isInc, isPacked, itemListenerK, keyListener, keyListenerK,\nLEFT_ALIGNMENT, locale, LOCK, minSize, mouseListener, mouseListenerK,\nmouseMotionListener, mouseMotionListenerK, name, nameExplicitlySet, newEventsOnly,\nownedWindowK, parent, peer, peerFont, popups, prefSize, RIGHT_ALIGNMENT,\nserialVersionUID, textListenerK, TOP_ALIGNMENT, valid, visible, width,\nwindowListenerK, x, y\n\n### Constructor Summary\n\n**ExecSupportMenu**\n\n(caps.CAPSM ain.CAPSM ainWindow owner)\n\nConstructor for this class.\n\n### Method Summary\n\n#### `void actionPerformed(java.awt.event.ActionEvent e)`\n\nAction event handler for the menu events.\n\n### Methods inherited from class `javax.swing.JMenuItem`\n\n- add, add, add, add, addMenuListener, addSeparator, buildMenuElementArray,\nclearListenerRegistry, createActionChangeListener, createMenuChangeListener,\ncreateWindowListener, doClick, ensurePopupMenuCreated, fireMenuCanceled,\nfireMenuDeselected, fireMenuSelected, getAccessibleContext, getComponent, getDelay,\ngetItem, getItemCount, getMenuComponent, getMenuComponentCount, getMenuComponents,\ngetPopupMenu, getPopupMenuOrigin, getSubElements, getUIClassID, insert, insert,\ninsertSeparator, isMenuComponent, isPopupMenuVisible, isSelected, isTearOff,\nisTopLevelMenu, menuSelectionChanged, paramString, processKeyEvent,\nregisterMenuItemsForAction, remove, remove, remove, removeAll, removeMenuListener,\nsetAccelerator, setDelay, setMenuLocation, setModel, setPopupMenuVisible,\nsetSelected, translateToPopupMenu, translateToPopupMenu,\nunregisterMenuItemsForAction, updateUI, writeObject\n### Methods inherited from class `javax.swing.JMenuItem`\n\n- `addMouseListener`, `addMenuKeyListener`, `alwaysOnTop`, `fireMenuDragMouseDragged`, `fireMenuDragMouseEntered`, `fireMenuDragMouseExited`, `fireMenuDragMouseReleased`, `fireMenuKeyPressed`, `fireMenuKeyReleased`, `fireMenuKeyTyped`, `getAccelerator`, `init`, `isArmed`, `processKeyEvent`, `processMenuDragMouseEvent`, `processMenuKeyEvent`, `processMouseEvent`, `readObject`, `removeMenuDragMouseListener`, `removeMenuKeyListener`, `setArmed`, `setEnabled`, `setUI`\n\n### Methods inherited from class `javax.swing.AbstractButton`\n\n- `addActionListener`, `addChangeListener`, `addItemListener`, `checkHorizontalKey`, `checkVerticalKey`, `createActionListener`, `createChangeListener`, `createItemListener`, `doClick`, `fireActionPerformed`, `fireStateChanged`, `getActionCommand`, `getDisabledIcon`, `getDisabledSelectedIcon`, `getHorizontalAlignment`, `getHorizontalTextPosition`, `getIcon`, `getLabel`, `getMargin`, `getMnemonic`, `getModel`, `getPressedIcon`, `getRolloverIcon`, `getRolloverSelectedIcon`, `getSelectedIcon`, `getSelectedObjects`, `getText`, `getUI`, `getVerticalAlignment`, `getVerticalTextPosition`, `isBorderPainted`, `isContentAreaFilled`, `isFocusPainted`, `isRolloverEnabled`, `paintBorder`, `removeActionListener`, `removeChangeListener`, `removeItemListener`, `setActionCommand`, `setBorderPainted`, `setContentAreaFilled`, `setLabel`, `setDisabledIcon`, `setDisabledSelectedIcon`, `setFocusPainted`, `setHorizontalAlignment`, `getHorizontalTextPosition`, `setIcon`, `setLabel`, `setMargin`, `setMnemonic`, `setPressedIcon`, `setRolloverEnabled`, `setRolloverIcon`, `setRolloverSelectedIcon`, `setSelectedIcon`, `setText`, `setUI`, `setVerticalAlignment`, `setVerticalTextPosition`\n\n### Methods inherited from class `javax.swing.JComponent`\n\n- `_paintImmediately`, `addAncestorListener`, `addNotify`, `addPropertyChangeListener`, `addPropertyChangeListener`, `addVetoableChangeListener`, `adjustPaintFlags`, `bindingForKeyStroke`, `checkIfChildObscuredBySibling`, `computeVisibleRect`, `contains`, `createToolTip`, `enableSerialization`, `firePropertyChange`, `firePropertyChange`, `firePropertyChange`, `firePropertyChange`, `firePropertyChange`, `fireVetoableChange`, `getActionForKeyStroke`, `getAlignment`, `getAlignmentY`, `getAutoscrolls`, `getBorder`, `getBounds`, `getClientProperties`, `getClientProperty`, `getComponentGraphics`, `getConditionForKeyStroke`, `getDebugGraphicsOptions`, `getPostion`, `getGraphics`, `getHeight`, `getInsets`, `getInsets`, `getLocation`, `getMaximumSize`, `getMinimumSize`, `getNextFocusableComponent`, `getPreferredSize`, `getRegisteredKeyStrokes`, `getRootPane`, `getSize`, `getToolTipLocation`, `getToolTipText`, `getToolTipText`, `getTopLevelAncestor`, `getVisibleRect`, `getWidth`, `getX`, `getY`, `grabFocus`, `hasFocus`, `isDoubleBuffered`, `isFocusCycleRoot`, `isFocusTraversable`, `isLightweightComponent`, `isManagingFocus`, `isOpaque`, `isOptimizedDrawingEnabled`, `isPaintingFile`, `isRequestFocusEnabled`, `isValidateRoot`, `keyDown`, `paint`, `paintChildren`, `paintComponent`, `paintImmediately`, `paintImmediately`, `paintWithBuffer`, `processComponentKeyEvent`, `processFocusEvent`, `processKeyBinding`, `processKeyBindings`, `processKeyBindingsForAllComponents`, `processMouseMotionEvent`, `putClientProperty`, `rectangleIsObscured`, `rectangleIsObscuredBySibling`, `registerKeyboardAction`, `registerWithKeyboardManager`, `removeAncestorListener`, `removeNotify`, `removePropertyChangeListener`, `removePropertyChangeListener`, `removeVetoableChangeListener`, `repaint`, `repaint`, `requestDefaultFocus`, `requestFocus`, `resetKeyboardActions`, `reshape`, `revalidate`, `scrollRectToVisible`, `setAlignment`, `setAlignmentX`, `setAutoscrolls`, `setBackground`, `setBorder`, `setDebugGraphicsOptions`, `setDoubleBuffered`, `setFlag`, `setFont`, `setForeground`, `getMaximumSize`, `getMinimumSize`, `getNextFocusableComponent`, `setOpaque`, `setPaintedChild`, `setPreferredSize`, `setRequestFocusEnabled`, `setToolTipText`, `setUI`, `setVisible`, `shouldDebugGraphics`, `superProcessMouseMotionEvent`, `unregisterKeyboardAction`, `unregisterWithKeyboardManager`, `update`\nMethods inherited from class java.awt.Container\n\nadd, add, add, add, addContainerListener, addImpl, applyOrientation, countComponents, deliverEvent, dispatchEventImpl, dispatchEventToSelf, doLayout, eventEnabled, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentNoClientCode, getComponents, getCursorTarget, getLayout, getMouseMotionTarget, getWindow, initIDs, insets, invalidate, invalidatedTree, isAncestorOf, layout, lightweightPrint, list, list, locate, minimumSize, nextFocus, paintComponents, postProcessKeyEvent, postsOldMouseEvents, preferredSize, preProcessKeyEvent, print, printComponents, printOneComponent, processContainerEvent, processEvent, proxyEnableEvents, proxyRequestFocus, removeContainerListener, setCursor, setFocusOwner, setLayout, transferFocus, updateCursor, validate, validateTree\n\nMethods inherited from class java.awt.Component\n\naction, add, addComponentListener, addFocusListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, areInputMethodsEnabled, bounds, checkImage, checkImage, coalesceEvents, constructComponentName, contains, createImage, createImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, getBackground, getBounds, getColorModel, getComponentOrientation, getCursor, getDropTarget, getFont, getFontMetrics, getForeground, getApplicationContext, getComponentRequestSource, getFocus, getFocus, getLocale, getLocation, getLocationOnScreen, getName, getNativeContainer, getParentNoClientCode, getParent, getParent, getPeer, getSize, getToolkit, getToolkitImpl, getNextFocus, getWindowForObject, getFocus, handleEvent, hide, imageUpdate, inside, isDisplayable, isEnabled, isEnabledImpl, isLightweight, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, printAll, processComponentEvent, processInputMethodEvent, processMouseEvent, remove, removeComponentListener, removeFocusListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, repaint, repaint, repaint, resize, setBounds, setBounds, setComponentOrientation, setDropTarget, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus\n\nMethods inherited from class java.lang.Object\n\nclose, equals, finalize, getClass, hashCode, notify, notifyAll, registerNatives, wait, wait, wait\n\nField Detail\n\ntranslateMenuItem\n\nprivate javax.swing.JMenuItem translateMenuItem\n\nInitializes the 'Translate' event\n\nscheduleMenuItem\n\nprivate javax.swing.JMenuItem scheduleMenuItem\nInitiates the 'Schedule' event\n\n---\n\n**compileMenuItem**\n\n```java\nprivate javax.swing.JMenuItem compileMenuItem\n\n Initiates the 'Compile' event\n```\n\n---\n\n**executeMenuItem**\n\n```java\nprivate javax.swing.JMenuItem executeMenuItem\n\n Initiates the 'Execute' event\n```\n\n---\n\n**ownerWindow**\n\n```java\nprotected caps.CAPSMain.CAPSMainWindow ownerWindow\n\n The main window which owns this menu.\n```\n\n---\n\n### Constructor Detail\n\n**ExecSupportMenu**\n\n```java\npublic ExecSupportMenu(caps.CAPSMain.CAPSMainWindow owner)\n\n Constructor for this class.\n **Parameters:**\n - `owner` - CAPSMainWindow that owns the menu\n```\n\n---\n\n### Method Detail\n\n**actionPerformed**\n\n```java\npublic void actionPerformed(java.awt.event.ActionEvent e)\n\n Action event handler for the menu events.\n **Specified by:**\n - actionPerformed in interface java.awt.event.ActionListener\n **Parameters:**\n - `e` - The action event that is created by selecting a menu item\n```\n\n156\ncaps.CAPSMain\n\nClass PrototypeMenu\n\njava.lang.Object\n +--java.awt.Component\n +--java.awt.Container\n +--javax.swing.JComponent\n +--javax.swing.AbstractButton\n +--javax.swing.JMenuItem\n +--javax.swing.JMenuItem\n +--caps.CAPSMain.PrototypeMenu\n\npublic class PrototypeMenu\nextends javax.swing.JMenuItem\nimplements java.awt.event.ActionListener\n\nThis class holds the 'Prototype' menu items.\n\nSee Also:\n Serialized Form\n\nInner classes inherited from class javax.swing.JMenuItem\n\njavax.swing.JMenuItem.Accessible JMenuItem, javax.swing.JMenuItem.ActionListener,\njavax.swing.JMenuItem.WinListener\n\nInner classes inherited from class javax.swing.JMenuItem\n\njavax.swing.JMenuItem.Accessible JMenuItem\n\nInner classes inherited from class javax.swing.AbstractButton\n\njavax.swing.AbstractButton.AccessibleAbstractButton,\njavax.swing.AbstractButton.ActionListener\nInner classes inherited from class java.swing.JComponent\n\njavax.swing.JMenuItem, javax.swing.JMenuItem.AccessibleJComponent, javax.swing.JMenuItem.IntVector,\njavax.swing.JMenuItem.KeyboardBinding, javax.swing.JMenuItem.KeyboardState\n\nInner classes inherited from class java.awt.Component\n\njava.awt.Component.AWTTreeLock\n\n### Field Summary\n\n<table>\n<thead>\n<tr>\n<th>Field Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>commitWorkMenuItem</td>\n<td>Initiates the 'Commit Work' event</td>\n</tr>\n<tr>\n<td>newMenuItem</td>\n<td>Initiates the 'New' event</td>\n</tr>\n<tr>\n<td>openMenuItem</td>\n<td>Initiates the 'Open' event</td>\n</tr>\n<tr>\n<td>ownerWindow</td>\n<td>The main window which owns this menu.</td>\n</tr>\n<tr>\n<td>quitMenuItem</td>\n<td>Initiates the 'Quit' event</td>\n</tr>\n<tr>\n<td>retrieveMenuItem</td>\n<td>Initiates the 'Retrieve From DDB' event</td>\n</tr>\n</tbody>\n</table>\n\n### Fields inherited from class java.swing.JMenu\n\ndelay, listenerRegistry, menuChangeListener, menuEvent, popupListener, popupMenu, uiClassID\n\n### Fields inherited from class java.swing JMenuItem\n\naccelerator, uiClassID\n\n### Fields inherited from class java.swing JButton\n\nactionListener, BORDER_PAINTED_CHANGED_PROPERTY, changeEvent, changeListener,\nCONTENT_AREA FILLED_CHANGED_PROPERTY, ContentAreaFilled, defaultIcon, defaultMargin,\nDISABLED_ICON_CHANGED_PROPERTY, DISABLED_SELECTED_ICON_CHANGED_PROPERTY,\ndisabledIcon, disabledSelectedIcon, FOCUS PAINTED_CHANGED_PROPERTY,\nHORIZONTAL_ALIGNMENT_CHANGED_PROPERTY, HORIZONTAL_TEXT_POSITION_CHANGED_PROPERTY,\nhorizontalAlignment, horizontalTextPosition, ICON_CHANGED_PROPERTY, itemListener,\nmargin, MARGIN_CHANGED_PROPERTY, MNEMONIC_CHANGED_PROPERTY, model,\nMODEL_CHANGED_PROPERTY, paintBorder, paintFocus, PRESS_CHANGED_PROPERTY,\npresstedIcon, ROLLER_ENABLED_CHANGED_PROPERTY, ROLLER_ICON_CHANGED_PROPERTY,\nROLLER_SELECTED_ICON_CHANGED_PROPERTY, rolloverEnabled, rolloverIcon,\nrolloverSelectedIcon, SELECTED_ICON_CHANGED_PROPERTY, selectedIcon, text,\nTEXT_CHANGED_PROPERTY, VERTICAL_ALIGNMENT_CHANGED_PROPERTY,\nVERTICAL_TEXT_POSITION_CHANGED_PROPERTY, verticalAlignment, verticalTextPosition\nFields inherited from class `javax.swing.JComponent`\n\n- _bounds, accessibleContext, alignmentX, alignmentY, ANCESTOR_USING_BUFFER, ancestryNotifier, autoscrollbar, border, changeSupport, clientProperties, flags, HAS_FOCUS, IS_DOUBLE_BUFFERED, IS_OPAQUE, IS_PAINTING_TILE, KEYBOARD_BINDINGS_KEY, listenerList, maximumSize, minimumSize, NEXT_FOCUS, paintImmediatelyClip, paintingChild, preferredSize, readObjectCallables, REQUEST_FOCUS_DISABLED, tmpRect, TOOL_TIP_TEXT_KEY, ui, uiClassID, UNDEFINED_CONDITION, vetoableChangeSupport, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW\n\nFields inherited from class `java.awt.Container`\n\n- component, containerListener, containerSerializedDataVersion, dispatcher, layoutMgr, maxSize, ncomponents, serialVersionUIDUID\n\nFields inherited from class `java.awt.Component`\n\n- actionListenerK, adjustmentListenerK, appContext, assert, background, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, changeSupport, componentListener, componentListenerK, componentOrientation, componentSerializedDataVersion, containerListenerK, cursor, dropTarget, enabled, eventMask, focusListener, focusListenerK, font, foreground, hasFocus, height, incRate, inputMethodListener, inputMethodListenerK, isInc, isPacked, itemListenerK, keyListener, keyListenerK, LEFT_ALIGNMENT, locale, LOCK, minSize, mouseListener, mouseListenerK, mouseMotionListener, mouseMotionListenerK, name, nameExplicitlySet, newEventsOnly, ownedWindowK, parent, peer, peerFont, popups, prefSize, RIGHT_ALIGNMENT, serialVersionUIDUID, textFieldListenerK, TOP_ALIGNMENT, valid, visible, width, windowListenerK, x, y\n\nConstructor Summary\n\n**PrototypeMenu** (caps.CAPSMain.CAPSMainWindow owner)\n\nConstructor for this class.\n\nMethod Summary\n\n- **void** `actionPerformed(java.awt.event.ActionEvent e)`\n \n Action event handler for the menu events.\n\n- **void** `processCommitWorkMenuItems()`\n \n Handles the event which is caused by selecting the 'Commit' menu item.\n\n- **void** `processNewItem()`\n \n Handles the event which is caused by selecting the 'New' menu item.\n\n- **void** `processOpenMenuItems()`\n \n Handles the event which is caused by selecting the 'Open' menu item.\n### Methods inherited from class `javax.swing.JMenuItem`\n\n- `addActionListener`, `addChangeListener`, `addItemListener`, `checkHorizontalKey`, `checkVerticalKey`, `createActionChangeListener`, `createChangeListener`, `createItemListener`, `doClick`, `fireActionPerformed`, `fireItemStateChanged`, `fireStateChanged`, `getActionCommand`, `getDisabledIcon`, `getDisabledSelectedIcon`, `getHorizontalAlignment`, `getHorizontalTextPosition`, `getIcon`, `getLabel`, `getMargin`, `getMnemonic`, `getModel`, `getPressedIcon`, `getRolloverIcon`, `getRolloverSelectedIcon`, `getSelectedIcon`, `getSelectedObjects`, `getText`, `getUI`, `getVerticalAlignment`, `getVerticalTextPosition`, `isBorderPainted`, `isContentAreaFilled`, `isFocusPainted`, `isRolloverEnabled`, `paintBorder`, `removeActionListener`, `removeChangeListener`, `removeItemListener`, `setActionCommand`, `setBorderPainted`, `setContentAreaFilled`, `setDisabledIcon`, `setDisabledSelectedIcon`, `setFocusPainted`, `setHorizontalAlignment`, `setHorizontalTextPosition`, `setIcon`, `setLabel`, `setMargin`, `setMnemonic`, `setPressedIcon`, `setRolloverEnable`, `setRolloverIcon`, `setRolloverSelectedIcon`, `setSelectedIcon`, `setText`, `setUI`, `setVerticalAlignment`, `setVerticalTextPosition`\nMethods inherited from class javax.swing.JComponent\n\n- paintImmediately, addAncestorListener, addNotify, addPropertyChangeListener, addPropertyChangeListener, addVetoableChangeListener, adjustPaintFlags, bindingForKeyStroke, checkIfChildObscuredBySibling, computeVisibleRect, computeVisibleRect, contains, createToolTip, enable TLS, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getActionForKeyStroke, getAlignmentX, getAlignmentY, getAutoscrolls, getBorder, getBounds, getClientProperties, getClientProperty, getComponentGraphics, getConditionForKeyStroke, getDebugGraphicsOptions, getFlag, getGraphics, getHeight, getInsets, getInsets, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getVisibleRect, getWidth, getX, getY, grabFocus, hasFocus, isDoubleBuffered, isFocusCycleRoot, isFocusTraversable, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingTile, isRequestFocusEnabled, isValidateRoot, keyboardBindings, paint, paintChildren, paintComponent, paintImmediately, paintImmediately, paintWithBuffer, processComponentKeyEvent, processFocusEvent, processKeyBinding, processKeyBindings, processKeyBindingsForAllComponents, processMouseMotionEvent, putClientProperty, rectangleIsObscured, rectangleIsObscuredBySibling, registerKeyboardAction, registerKeyboardAction, registerWithKeyboardManager, removeAncestorListener, removeNotify, removePropertyChangeListener, removePropertyChangeListener, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setAlignmentX, setAlignmentY, set Autoscrolls, setBackground, setBorder, setDebugGraphicsOptions, setDoubleBuffered, setFlag, setFont, setForeground, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPaintingChild, setPreferredSize, setRequestFocusEnabled, setToolTipText, setUI, setVisible, shouldDebugGraphics, superProcessMouseMotionEvent, unregisterKeyboardAction, unregisterWithKeyboardManager, update\n\nMethods inherited from class java.awt.Container\n\n- add, add, add, add, addContainerListener, addImpl, applyOrientation, countComponents, deliverEvent, dispatchEvent, dispatchEventToSelf, doLayout, eventEnabled, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents_NoClientCode, getComponents, getCursorTarget, getLayout, getMouseMotionTarget, getWindow, initIDs, insets, invalidate, invalidateTree, isAncestorOf, layout, lightweightPrint, list, list, locate, minimumSize, nextFocus, pain Components, postProcessKeyEvent, postsOldMouseEvents, preferredSize, preProcessKeyUpEvent, print, printComponents, printOneComponent, processContainerEvent, processEvent, proxyEnableEvents, proxyRequestFocus, removeContainerListener, setCursor, setFocusOwner, setLayout, transferFocus, updateCursor, validate, validateTree\n\n161\nMethods inherited from class java.awt.Component\n\naction, add, addComponentListener, addFocusListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, areInputMethodsEnabled, bounds, checkImage, checkImage, coalesceEvents, constructComponentName, contains, createImage, createImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, getBackground, getBounds, getColorModel, getComponentOrientation, getCursor, getDropTarget, getFont_NoClientCode, getFont, getFontMetrics, getForeground, getInputContext, getInputMethodRequests, getIntrinsicCursor, getLocale, getLocation, getLocationOnScreen, getName, getNativeContainer, getParent_NoClientCode, getParent, getPeer, getSize, getToolkit, getToolkitImpl, getTreeLock, getWindowForObject, gotFocus, handleEvent, hide, imageUpdate, inside, isDisplayable, isEnabled, isEnabledImpl, isLightweight, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, printAll, processComponentEvent, processInputMethodEvent, processMouseEvent, remove, removeComponentListener, removeFocusListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, repaint, repaint, repaint, resize, resize, setBounds, setBounds, setComponentOrientation, setDropTarget, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus\n\nMethods inherited from class java.lang.Object\n\nclose, equals, finalize, getClass, hashCode, notify, notifyAll, registerNatives, wait, wait, wait\n\nField Detail\n\nnewMenuItem\n\nprivate javax.swing.JMenuItem newMenuItem\n\n Initiates the 'New' event\n\nopenMenuItem\n\nprivate javax.swing.JMenuItem openMenuItem\n\n Initiates the 'Open' event\n\ncommitWorkMenuItem\n\nprivate javax.swing.JMenuItem commitWorkMenuItem\n\n Initiates the 'Commit Work' event\nretrievemenultem\nprivate javax.swing JMenuItem retrievemenultem\n\n Initiates the 'Retrieve From DDB' event\n\nquitmenultem\nprivate javax.swing JMenuItem quitmenultem\n\n Initiates the 'Quit' event\n\nownerwindow\nprotected caps.CAPSMain.CAPSMainWindow ownerwindow\n\n The main window which owns this menu.\n\n### Constructor Detail\n\nPrototypeMenu\n\npublic PrototypeMenu(caps.CAPSMain.CAPSMainWindow owner)\n\n Constructor for this class.\n\n Parameters:\n owner - The main window which has created this menu.\n\n### Method Detail\n\nactionperformed\n\npublic void actionPerformed(java.awt.event.ActionEvent e)\n\n Action event handler for the menu events.\n\n Specified by:\n actionPerformed in interface java.awt.event.ActionListener\n\n Parameters:\n e - The action event that is created by selecting a menu item from this menu\n\nprocessNewMenuItem\n\npublic void processNewMenuItem()\nHandles the event which is caused by selecting the 'New' menu item.\n\n**processOpenMenuItem**\n\npublic void processOpenMenuItem()\n\nHandles the event which is caused by selecting the 'Open' menu item.\n\n**processCommitWorkMenu.Item**\n\npublic void processCommitWorkMenu.Item()\n\nHandles the event which is caused by selecting the 'Commit' menu item.\n### APPENDIX E: ACRONYMS\n\n<table>\n<thead>\n<tr>\n<th>Acronym</th>\n<th>Full Form</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CAPS</td>\n<td>Computer Aided Prototyping System</td>\n</tr>\n<tr>\n<td>CASE</td>\n<td>Computer Aided Software Engineering</td>\n</tr>\n<tr>\n<td>CDR</td>\n<td>Common Data Representation</td>\n</tr>\n<tr>\n<td>CGI</td>\n<td>Common Gateway Interface</td>\n</tr>\n<tr>\n<td>CORBA</td>\n<td>Common Object Request Broker Architecture</td>\n</tr>\n<tr>\n<td>CPL</td>\n<td>Common Prototyping Language</td>\n</tr>\n<tr>\n<td>DCOM</td>\n<td>Distributed Component Object Model</td>\n</tr>\n<tr>\n<td>DII</td>\n<td>Dynamic Invocation Interface</td>\n</tr>\n<tr>\n<td>DII COE</td>\n<td>Defense Information Infrastructure Common Operating Environment</td>\n</tr>\n<tr>\n<td>DOD</td>\n<td>Department of Defense</td>\n</tr>\n<tr>\n<td>DSI</td>\n<td>Dynamic Skeleton Interface</td>\n</tr>\n<tr>\n<td>GAMBIT</td>\n<td>Graphical Approach to Modeling and Building Interactively a Technical System</td>\n</tr>\n<tr>\n<td>GUI</td>\n<td>graphical user interface</td>\n</tr>\n<tr>\n<td>HIS</td>\n<td>Heterogeneous Systems Integrator</td>\n</tr>\n<tr>\n<td>HTTP</td>\n<td>Hypertext Transfer Protocol</td>\n</tr>\n<tr>\n<td>IDE</td>\n<td>integrated development environments</td>\n</tr>\n<tr>\n<td>IDL</td>\n<td>Interface Definition Language</td>\n</tr>\n<tr>\n<td>JDK</td>\n<td>Java Developer Kit</td>\n</tr>\n<tr>\n<td>JDS</td>\n<td>Jackson Development System</td>\n</tr>\n<tr>\n<td>JVM</td>\n<td>Java Virtual Machine</td>\n</tr>\n<tr>\n<td>LAN</td>\n<td>local area network</td>\n</tr>\n<tr>\n<td>OMA</td>\n<td>Object Management Architecture</td>\n</tr>\n<tr>\n<td>OMG</td>\n<td>Object Management Group</td>\n</tr>\n<tr>\n<td>ORB</td>\n<td>Object Request Broker</td>\n</tr>\n<tr>\n<td>PC</td>\n<td>personal computer</td>\n</tr>\n<tr>\n<td>PROTO TECH</td>\n<td>Prototyping Technology</td>\n</tr>\n<tr>\n<td>PSDL</td>\n<td>Prototype System Design Language</td>\n</tr>\n<tr>\n<td>RaPIER</td>\n<td>Rapid Prototyping to Investigate End-user Requirements</td>\n</tr>\n<tr>\n<td>RMI</td>\n<td>Remote Method Invocations</td>\n</tr>\n<tr>\n<td>RPC</td>\n<td>remote procedure call</td>\n</tr>\n<tr>\n<td>SSDL</td>\n<td>System Specification and Design Language</td>\n</tr>\n<tr>\n<td>UML</td>\n<td>Unified Modeling Language</td>\n</tr>\n<tr>\n<td>WAN</td>\n<td>wide area network</td>\n</tr>\n<tr>\n<td>WWW</td>\n<td>World Wide Web</td>\n</tr>\n</tbody>\n</table>\nLIST OF REFERENCES\n\n\nMILL90 North Carolina University at Chapel Hill Computer Science Department, Report TR90-041, *Prototyping Parallel and Distributed Programs in Proteus*, by Peter Mills, Lars Nyland, Jan Prins, John Reif, and Robert Wagner, pp.1-5, October 1990\n\n\nINITIAL DISTRIBUTION LIST\n\n1. Defense Technical Information Center ........................................... 2\n 8725 John J. Kingman Road, Ste 0944\n Ft. Belvoir, Virginia 22060-6218\n\n2. Dudley Knox Library ............................................................... 2\n Naval Postgraduate School\n 411 Dyer Rd.\n Monterey, California 93943-5101\n\n3. Dr Dan Boger, Chairman, Code CS ............................................. 1\n Computer Science Department\n Naval Postgraduate School\n Monterey, CA 93940-5000\n\n4. Dr Man-Tak Shing ................................................................. 1\n Computer Science Department, Code CS/Sh\n Naval Postgraduate School\n Monterey, California 93943-5100\n\n5. Dr Luqi .................................................................................. 1\n Computer Science Department, Code CS/Lq\n Naval Postgraduate School\n Monterey, California 93943-5100\n\n6. CDR Gary Kreeger ................................................................. 1\n 1011 Leahy Road\n Monterey, CA 93940\n\n7. LCDR Chris Eagle ................................................................. 1\n Computer Science Department, Code CS/Ce\n Naval Postgraduate School\n Monterey, CA 93943-5100"}}},{"rowIdx":82,"cells":{"id":{"kind":"string","value":"595c61f133c83f54377587cfb2dc18d2139ade75"},"text":{"kind":"string","value":"Cloud Object Storage\nDeveloper Guide\nProduct Documentation\nCopyright Notice\n\n©2013-2019 Tencent Cloud. All rights reserved.\n\nCopyright in this document is exclusively owned by Tencent Cloud. You must not reproduce, modify, copy or distribute in any way, in whole or in part, the contents of this document without Tencent Cloud's the prior written consent.\n\nTrademark Notice\n\nAll trademarks associated with Tencent Cloud and its services are owned by Tencent Cloud Computing (Beijing) Company Limited and its affiliated companies. Trademarks of third parties referred to in this document are owned by their respective proprietors.\n\nService Statement\n\nThis document is intended to provide users with general information about Tencent Cloud's products and services only and does not form part of Tencent Cloud's terms and conditions. Tencent Cloud's products or services are subject to change. Specific products and services and the standards applicable to them are exclusively provided for in Tencent Cloud's applicable terms and conditions.\nContents\n\nDeveloper Guide\n Creating Request\n Creating Request Overview\n Bucket\n Bucket Overview\n Creating Buckets\n Deleting Buckets\n Object\n Object Overview\n Storage Type\n Uploading Object\n Simple Upload\n Multipart Upload\n Upload via Pre-Signed URL\n Obtaining Object\n Obtaining Object Simply\n Download via Pre-Signed URL\n Listing Object Keys\n Copying Objects\n Simple Copy\n Multipart Copy\n Deleting Object\n Deleting a Single Object\n Deleting Multiple Objects\n\nData Management\n Inventory Overview\n Bucket Tag Overview\n Lifecycle Management\n Lifecycle Overview\n Elements of Lifecycle Configuration\n Configuring Lifecycle\n Static Website Hosting\n Event Notifications\n Data Extraction\n SELECT Overview\n SELECT Command\n SQL Functions\n Reserved Words\n Data Types\n Operators\n Log Management\n Log Management Overview\n Restrictions on Log Management\n Data Disaster Recovery\n Versioning\n Versioning Overview\n Using Versioning\n Versioning Configuration\nCross-region Replication\n Cross-region Replication Overview\n Replication Behavior Descriptions\n Cross-region Replication Configuration\n\nData Security\n Server-side Encryption Overview\n Bucket Encryption Overview\n\nCloud Access Management (CAM)\n Access Control\n Basic Concepts of Access Control\n Notes on Principle of Least Privilege\n Policy-based Access Control\n Access Policy Language Overview\n Examples of Bucket Policies\n ACL-based Access Control\n ACL Overview\n Tag-based Access Control\n Manage project resources based on tags\n Using CDN to Accelerate Access\n CDN Acceleration Overview\n CDN Acceleration Configuration\n Configuring GCD\n Single link speed limit\n\nBatch Processing\n Overview\n Performing Batch Operation\n Copying Objects in Batches\n Batch Resume archive object\n Managing Batch Operation Jobs\n\nMonitoring and Alarming\n Global Acceleration\n Overview\nConcept\n\nTencent Cloud COS is a web-based storage service accessed using the HTTP/HTTPS protocol. You can use the REST API or COS SDK to access COS.\n\nYour COS access request must first pass the COS verification and authentication before COS starts to operate the resources. Therefore, depending on whether the identity is identifiable, COS access requests are divided into two types: anonymous requests and requests with signatures.\n\n- **Anonymous request**: If the request does not include Authorization or related parameters, or the user identity cannot be identified based on the related characters, the request will be treated as an anonymous request for authentication.\n- **Request with signature**: A request with a signature must contain the Authorization field in the HTTP header or the request package. The content of the field is generated based on Tencent Cloud security credentials (SecretID and SecretKey) and some eigenvalues of the request via an encryption algorithm.\n\nTo access COS using COS SDKs, you only need to configure your security credentials before initiating the request. To access COS using the REST API, calculate the request signature according to Request Signature.\n\nObtaining Security Credentials\n\nCloud Access Management (CAM) provides features and services related to accounts and credentials for COS, to help customers manage the permissions to access resources under their Tencent Cloud accounts in a secure way. You can use CAM to create, manage and terminate users (or user groups), and manage other users’ permissions to use Tencent Cloud resources through identity management and policy management.\n\n**Security certificates of the primary account**\n\nAfter logging in to the primary account, you can manage and obtain the security credentials (SecretID and SecretKey) of your primary account on the Cloud API Key page of CAM. The following is a key pair example:\n\n| 36-character access key ID (SecretID): AKIDHZRLB9ibhdp7Y7gyQq6BOk1997BGmUXg |\n| 32-character access Key (SecretKey): LYaWIuQmCSZ5MniUM6hiaLxHnW6XxRK |\n\nThe access key can be used to identify the uniqueness of an account. After the signature is generated using the key and the request is sent, Tencent Cloud will identify the identity of the request initiator, and then perform verification and authentication for the identity, resources, operations, and conditions to determine whether to allow the operation.\n\n- The key of the primary account has all the operation permissions for all resources under the primary account. Disclosure of the key may cause loss of your cloud assets, so it is strongly recommended that you create sub-accounts and assign corresponding permissions for them, and then use the keys of sub-accounts to create requests for resource access and management.\nSecurity certificates of sub-accounts\n\nTo manage users and cloud resources under your account in multiple dimensions, you can create multiple sub-accounts under your primary account to implement user-specific permission management. For more information on how to create a sub-account, see Sub-users in CAM.\n\nBefore using a sub-account to initiate an API request, you need to create a security credential for the sub-account, and then the sub-account will get a unique key pair, which can facilitate the identification of the identity. You can create user policies for different sub-accounts to control their access permissions to resources. You can also create user groups and associate one access policy to a user group to facilitate the central management of user grouping and resources.\n\nWith the corresponding permissions assigned, a sub-account can create or modify resources. The resources still belong to the primary account, and the resource cost will be deducted from the primary account.\n\nTemporary security credentials\n\nIn addition to using security credentials of the primary account or sub-accounts to access resources, you can create roles and use the temporary security credentials of the roles to manage your Tencent Cloud resources. For more information on the role concept and how to use roles, see Role Overview.\n\nAs a virtual identity, a role does not have a permanent key. CAM provides a set of STS APIs used to generate temporary security credentials.\n\nFor more information on how to use the APIs and relevant examples, see Using Roles. See STS API to learn about how to generate temporary security credentials. Temporary security credentials contain only limited policies (operations, resources, and conditions), and are valid for a limited period (start and end time), so the generated temporary security credentials can be distributed or used directly.\n\nYou can call the API for to generate temporary security credentials and get a temporary key pair (tmpSecretId/tmpSecretKey) and a security token (sessionToken), which form the security credential that can be used to access COS. Here is a temporary security credential example:\n\n| 41-character security token (SecurityToken): 5e776c4216ff4d31a7c74fe194a978a3ff2a42864 |\n| 36-character temporary access key ID (SecretID): AKIDcAZnqgar9ByWq6m7ucln8LNEuY2MkPCI |\n| 32-character temporary access key (SecretKey): VpxrX0IMCpHXWL0r3KQCijx1uhMqD |\n\nThis API also returns the validity period of the temporary security credential via the expiration field, which means that this set of security credentials can only be used to initiate requests during this period.\n\nTencent Cloud COS provides a simple server SDK that can be used to generate temporary keys. You can visit COS STS SDK to obtain the SDK. To initiate the request using the REST API after getting the temporary security credential, you need to specify the value for the x-cos-security-token field in the HTTP header or the form-data of the POST request package to identify the security token used by the request, and then use the temporary access key pair to generate the request signature. For more information on how to initiate requests using the COS SDK, see the relevant sections in each SDK documentation.\n\nAccess Domain Name\n\nREST API\n\nThe Region and Access Domain Name document provides a list of domain names that can be used to initiate access requests via the REST API.\nIt is recommended to use virtual hosting domain names to access COS buckets. When you initiate an HTTP request, the bucket to be accessed will be specified through the `Host` header, such as `<BucketName-APPID>.cos.<Region>.myqcloud.com`. Using virtual hosting domain names realizes the same feature as the \"root\" of a virtual server. Virtual hosting domain names can be used to host files such as favicon.ico, robots.txt, and crossdomain.xml, which are the content that many applications will retrieve from the \"root\" of the virtual server by default when identifying a hosted website.\n\nYou can also use a path request to access a bucket, such as `cos.<region>.myqcloud.com/<BucketName-APPID>/`. The request Host and the signature must use `cos.<region>.myqcloud.com`. SDK does not support this access method by default.\n\n### Domain name of static websites\n\nIf you enable the static website feature, a virtual hosting domain name will be assigned for you to use relevant features. Unlike the REST API, the domain name of static website only supports a few operations, such as GET/HEAD/OPTIONS Object, in addition to specific index pages, error pages and redirection configurations. Uploading or configuring resources is not supported.\n\nThe format of a domain name of a static website is `<BucketName-APPID>.cos-website.<Region>.myqcloud.com`. You can also log in to the console and go to the bucket's **Basic Configuration** -> **Static Website Configuration** to get the domain name.\n\n### COS Access via Private Network and Public Network\n\nThe access domain names of COS adopt intelligent DNS resolution. For COS access via Internet (including different ISPs), we will detect and select the optimal linkage for you to access COS. If you have deployed a service in Tencent Cloud to access COS, the access in the same region will be automatically directed to the private network address. The cross-region access is not supported in the private network and the COS domain name is resolved to the public network address by default.\n\n**How to determine an access via private network**\n\nTencent Cloud products within the same region access each other over a private network by default and no traffic fee is charged for these connections. For this reason, it is recommended to choose the same region when you purchase different Tencent Cloud products for cost saving.\n\nThe following shows how to determine whether it is an access via private network:\n\nFor example, when a CVM access COS, to determine whether a private network is used to access COS, use the `nslookup` command on the CVM to resolve the COS domain name. If a private network IP is returned, the access between CVM and COS is over a private network; otherwise, it is over a public network.\n\nGenerally, a private IP address takes the form of `10.0.0.0` or `100.0.0.0`, and a VPC IP address takes the form of `169.254.0.0`.\n\nAssume that `mybucket-1250000000.cos.ap-guangzhou.myqcloud.com` is the address of target bucket, and the `Address: 10.148.214,13` below it indicates the access is over the private network.\n\n```\nnslookup mybucket-1250000000.cos.ap-guangzhou.myqcloud.com\n\nServer: 10.138.224.65\nAddress: 10.138.224.65 #53\n\nName: mybucket-1250000000.cos.ap-guangzhou.myqcloud.com\nAddress: 10.148.214,13\nName: mybucket-1250000000.cos.ap-guangzhou.myqcloud.com\nAddress: 10.148.214,14\n```\n\n**Testing connectivity**\n\n**Basic connectivity test**\nCOS uses the HTTP protocol to provide services. You can use the most basic tool telnet to test the connectivity to port 80 of the COS access domain.\n\nAn example of access through the public network:\n\n```\ntelnet mybucket-1250000000.cos.ap-guangzhou.myqcloud.com 80\nTrying 14.119.113.22...\nConnected to gz.file.myqcloud.com.\nEscape character is '^]'.\n```\n\nAn example of access through Tencent Cloud CVMs (basic network) within the same region:\n\n```\ntelnet mybucket-1250000000.cos.ap-guangzhou.myqcloud.com 80\nTrying 10.148.214.14...\nEscape character is '^]'.\n```\n\nAn example of access through Tencent Cloud CVMs (VPC) within the same region:\n\n```\ntelnet mybucket-1250000000.cos.ap-guangzhou.myqcloud.com 80\nTrying 169.254.0.47....\nConnected to 169.254.0.47.\nEscape character is '^]'.\n```\n\nRegardless of the access environment, if the command returns the field, it indicates that the connection is successful.\n\n**Test via the Internet**\n\nSince the access to COS over the Internet involves the ISP network, which may prohibit you from testing connectivity using such tools as ping or traceroute of the ICMP protocol, so it is recommended to use the tools of the TCP protocol to test connectivity.\n\n```\nThe access via the Internet may involve multiple network environments. If the access is not smooth, check your local network linkage, or contact the local ISP.\n```\n\nIf your ISP allows you to use the ICMP protocol, you can use the ping, traceroute or mtr tools to check your linkage. Otherwise, you can use the psping (Windows environment; download at the Microsoft official website) or such tools as tcping (cross-platform software) to test the latency.\n\n**Test via the private network**\n\nIf you access the COS over the Tencent Cloud VPC in the same region, you may be unable to test connectivity using such tools as ping or traceroute of the ICMP protocol. It is recommended that you use the telnet command in the basic connectivity test to perform the testing.\n\nYou can also use the tools such as psping or tcping to test the latency to port 80 of the access domain. Before the test, make sure that the access domain name has been correctly resolved to the private network address using the nslookup command.\nBucket Overview\n\nLast updated: 2019-09-16 11:51:52\n\nDefinition\n\nA bucket is a carrier of objects, which can be considered as a \"container\" for storing objects. You can manage buckets and configure attributes of buckets in various methods such as the Tencent Cloud Console, APIs, and SDKs. For example, you can set a bucket for hosting a static website or set access permission to a bucket. For more information on bucket configuration, see the topics below:\n\n- Creating a Bucket\n- Setting up a Static Website\n- Setting Access Permission\n- Setting Hotlink Protection\n\nRegion\n\nRegion is where a COS IDC is located. COS allows you to create buckets in different regions. You can select the region closest to the location where your business is deployed for the buckets so as to reduce latency and cost and meet the compliance requirements.\n\nFor example, if your business is distributed in South China, creating buckets in the Guangzhou region can accelerate object uploads and downloads. For more information on regions, see Regions and Access Domain Names.\n\nNaming Conventions\n\nA bucket name consists of two parts: user-defined string and system-generated numeric string (APPID), which are connected by a dash \"-\". For example, in the bucket name examplebucket-1250000000, examplebucket is the user-defined string, and 1250000000 is the system-generated numeric string (APPID).\n\nIn the bucket name examples for APIs and SDKs, the naming format of a bucket is `<BucketName-APPID>`.\n\n- System-generated numeric string (APPID): automatically assigned by the system, which you do not need to specify and is unique in Tencent Cloud.\n- User-defined string: a string of characters entered manually by you, as specified below.\n\nNaming convention for user-defined strings:\n\n- You can only use lowercase letters [a-z], numbers [0-9], dashes \"-\", or a combination of them.\n- The length of a user-defined string cannot exceed 40 characters.\n- A bucket name cannot begin or end with \"-\".\n\nThe following are examples of valid bucket names:\n\n- mybucket123-1250000000\n- 1-newproject-1250000000\n\nType of Permission\nThree types of bucket access permissions are available by default, i.e., \"Private Read/Write\", \"Public Read/private Write\", and \"Public Read/Write\". You can modify bucket access permissions in Permission Management of the bucket in the COS Console. For more information, see Basic Concepts of Access Control.\n\n- Private Read/Write\n Only the creator of the bucket and authorized accounts have Read/Write permission to the objects in the bucket. The default access permission of a bucket is Private Read/Write, which is recommended.\n\n- Public Read/Private Write\n Anyone (including anonymous visitors) has Read permission to the objects in the bucket, but only the bucket creator and authorized accounts have Write permission to them.\n\n- Public Read/Write\n Anyone (including anonymous visitors) has Read/Write permission to the objects in the bucket, which is not recommended.\n\nDescriptions\n\n- COS stores objects in a flat structure with no traditional folder concept. For more information, see the Folder and Directory section in Object Overview.\n- You can create up to 200 buckets in total in all regions with one account. There is no limit on the number of objects in a bucket.\n- In Tencent Cloud COS, the bucket name under one APPID must be unique.\n- Once a bucket is created, it cannot be renamed. To rename a bucket, you need to delete it and create another one with the desired name.\n- When creating a bucket, make sure to select the desired region, as the region cannot be changed once specified.\nCreating Buckets\n\nUse Cases\n\nTo use COS, you need to create a bucket that helps you use and manage objects. You can create buckets via the console, APIs, or SDKs.\n\nYou can use the following sample code to create a bucket in the specified region. The supported parameters are:\n\n- **Bucket**: specify your full bucket name in the format of `examplebucket-1250000000`.\n- **Region**: select the region where your bucket resides. Once the bucket is created, the region cannot be modified. For more information, see Regions and Access Domain Names supported by COS.\n\nDirections\n\n**Via the COS Console**\n\nYou can create a bucket in the COS Console. For more information, see Creating a Bucket in Console Guide.\n\n**Via REST API**\n\nYou can use the REST API directly to initiate a bucket creating request. For more information, see PUT Bucket.\n\n**Via the SDK**\n\nYou can directly call the bucket creating method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\n- SDK for WeChat Mini Program\nDeleting Buckets\n\nUse Cases\n\nBuckets can be deleted via the console, APIs, or SDKs.\n\nOnly empty buckets can be deleted. If there are still objects in a bucket, its deletion will fail. Make sure that there are no objects in the bucket before deleting it.\n\nBefore deleting a bucket, make sure that the current identity has been granted the permission to delete it and that the correct Bucket and Region parameters are passed in.\n\nDirections\n\nVia the COS Console\n\nYou can delete a bucket in the COS Console. For more information, see Deleting a Bucket in Console Guide.\n\nVia REST API\n\nYou can use the REST API directly to initiate a bucket deleting request. For more information, see DELETE Bucket in API documentataion.\n\nVia the SDK\n\nYou can directly call the bucket deleting method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\nDefinition\n\nAn object is the basic unit of COS and is stored in a bucket just like a photo stored in an album. You can manage objects in different ways including Tencent Cloud Console, APIs, and SDKs. An object is named in the format of `<ObjectKey>`.\n\nObjects can be uploaded via simple upload or multipart upload.\n- Use simple upload for objects less than 5 GB.\n- Multipart upload is limited to no more than 10,000 parts (less than 5 GB per part) and a maximum object size of 48.82 TB.\n\nEach object consists of an object key (ObjectKey), a data value (Value), and object metadata (Metadata).\n- ObjectKey: the unique identifier of the object in the bucket.\n- Value: the size of the uploaded object.\n- Metadata: a set of name-value pairs that you can set when you upload an object.\n\nYou can configure objects in the console. For more information, see:\n- Searching for Objects\n- Viewing Object Information\n- Setting Object Access Permission\n- Setting Custom Headers\n\nObjectKey\n\nDefinition\n\nAn object in COS must contain a valid ObjectKey, which is the unique identifier of an object in a bucket.\n\nFor example, in an object's access address `examplebucket-1250000000.cos.ap-guangzhou.myqcloud.com/folder/picture.jpg`, the ObjectKey is `folder/picture.jpg`.\n\nNaming Convention\n\n- You can use any UTF-8 character in a key name. However, for the maximum compatibility with other applications, it is recommended to use uppercase and lowercase letters and numbers (i.e., [a-z, A-Z, 0-9]), special characters ( ~, !, $, %, ^, &, and *), and a combination of them.\n- The encoding length is up to 850 bytes.\n- An object key does not support some ASCII control characters, including upward arrow (↑), downward arrow (↓), rightward arrow (→), and leftward arrow (←), corresponding to CAN (24), EM (25), SUB (26), and ESC (27).\n- If the name of the uploaded file or folder contains Chinese characters, when you access or request the file or folder, the Chinese characters will be converted into a percent-encoded string according to URL-encoding rules.\n\nFor example, when you access `Document.doc`, the object key is `Document.doc`, while the percent-encoded string read is `%e6%96%87%e6%a1%a3.doc`.\n\nThe following are examples of valid key names:\nSpecial Characters\n\nCertain characters may need to be URL-encoded or referenced in the hexadecimal format. Some of them are non-printable characters and your browser might not be able to handle them. They’d require special handling, as shown below:\n\n<table>\n<thead>\n<tr>\n<th>,</th>\n<th>:</th>\n<th>;</th>\n<th>=</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>&</td>\n<td>$</td>\n<td>@</td>\n<td>+</td>\n</tr>\n<tr>\n<td>?</td>\n<td>ASCII character ranges: 00-1F hexadecimal (0-31 decimal) and 7F (127 decimal)</td>\n<td>(space)</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nThere are also some characters that require significant special handling to maintain consistency across all applications, so it is recommended to avoid them directly, as shown below:\n\n<table>\n<thead>\n<tr>\n<th>`</th>\n<th>^</th>\n<th>"</th>\n<th>\\</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>{</td>\n<td>}</td>\n<td>[</td>\n<td>]</td>\n</tr>\n<tr>\n<td>~</td>\n<td>%</td>\n<td>#</td>\n<td></td>\n</tr>\n<tr>\n<td>></td>\n<td><</td>\n<td>ASCII 128-255 decimal</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nAccess Address\n\nThe access address of the object consists of a bucket access address and an object key, in the format of `bucket domain name/object key`.\n\nFor example, when you upload the `exampleobject.txt` object to the `examplebucket-1250000000` bucket in Guangzhou (South China), the access address for `exampleobject.txt` is `examplebucket-1250000000.cos.ap-guangzhou.myqcloud.com/exampleobject.txt`.\n\nFolder and Directory\n\nAs COS comes with no folders or directories, it will not create a `project` folder for uploading the object `project/a.txt`. To make it easier for you to get started, COS simulates the display mode of \"folder\" or \"directory\" in the console and graphical tools such as COS browser. This is implemented by creating an empty object with a key value of `project/` and displaying it as a traditional folder.\n\nFor example, when you upload the object `project/doc/a.txt` via APIs or SDKs, the delimiter `/` simulates the display mode of \"folder\", and you can see the folders `project` and `doc` in the console. The folder `doc` is displayed under the folder `project` and contains the file `a.txt`.\n\nObjects in the bucket are evenly distributed among distributed clusters. Therefore, you cannot directly get the size of all objects with a specified object key prefix. Instead, you can accumulate the size of each object to get the full size.\n\nDeleting folders and directories is relatively complicated, as shown below:\n\n<table>\n<thead>\n<tr>\n<th>Deletion Means</th>\n<th>Deletion</th>\n<th>Result</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Console</td>\n<td>Folder <code>project</code></td>\n<td>All objects with the object key prefix <code>project/</code> will be deleted</td>\n</tr>\n<tr>\n<td>Console</td>\n<td>Object <code>project/doc/a.txt</code></td>\n<td>The <code>project</code> and <code>doc</code> folders will be retained</td>\n</tr>\n</tbody>\n</table>\nDeletion Means | Deletion | Result\n--- | --- | ---\nAPI and SDK | Object `project/` or `project/doc/` | The object `project/doc/\\*` will be retained. If you want to delete the objects in the folder, use code traversal to delete them\n\n**Metadata**\n\n**Definition**\n\nMetadata (aka HTTP header) is a set of name-value pairs in an object. It is the string sent by the server before the server sends HTML data using HTTP protocol to the browser. Modifying the HTTP header when uploading an object can alter page response forms or communicate configuration information, such as modifying caching time.\n\nThere are two types of metadata: system metadata and user-defined metadata.\n\n> Modifying an object’s HTTP header does not modify the object itself.\n\n**System Metadata**\n\nThis refers to the attribute information of the object, such as upload time or modification time.\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Date</td>\n<td>Current date and time</td>\n</tr>\n<tr>\n<td>Content-Length</td>\n<td>HTTP request content length in bytes as defined in RFC 2616, commonly used in API operations of PUT type</td>\n</tr>\n<tr>\n<td>Last-Modified</td>\n<td>Object creation date or the last modified date, whichever occurs later</td>\n</tr>\n<tr>\n<td>Content-MD5</td>\n<td>The Base64-encoded 128-bit MD5 checksum as defined in RFC 1864. This header is used to verify whether the file content has changed</td>\n</tr>\n<tr>\n<td>Authorization</td>\n<td>Authentication information, such as signature information used to verify the validity of request. For Public Read files, this header is not required</td>\n</tr>\n<tr>\n<td>x-cos-version-id</td>\n<td>Object version. If versioning is enabled for a bucket, the version ID of the object will be returned</td>\n</tr>\n<tr>\n<td>ETag</td>\n<td>Indicates the MD5 value of the uploaded file if the object is uploaded by PUT Object; indicates the unique ID of the uploaded file if the object is uploaded by multipart upload or using legacy of APIs, which cannot perform check though</td>\n</tr>\n<tr>\n<td>Expect</td>\n<td>HTTP request length in bytes as defined in RFC 2616</td>\n</tr>\n<tr>\n<td>Connection</td>\n<td>Connection status between the client and server. Enumerated values: keep-alive, close</td>\n</tr>\n</tbody>\n</table>\n\n**User-defined Metadata**\n\nThis refers to the object’s custom parameters, such as Content-Type, Cache-Control, Expires, and x-cos-meta-. For more information, see [Custom Object Headers](#).\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Cache-Control</td>\n<td>The caching policy as defined in RFC 2616, which will be saved as the object's metadata</td>\n</tr>\n<tr>\n<td>Name</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>Content-Disposition/Encoding/Type</td>\n<td>The file name/encoding format/content type (MIME) as defined in RFC 2616, which will be saved as the object’s metadata</td>\n</tr>\n<tr>\n<td>Expires</td>\n<td>Object cache expiration time. For more information, see Expires Descriptions</td>\n</tr>\n<tr>\n<td>x-cos-acl</td>\n<td>Defines the ACL attribute of an object. Value range: private, public-read-write, public-read. Default value: private</td>\n</tr>\n<tr>\n<td>x-cos-grant-*</td>\n<td>Grants permission to the authorized user.</td>\n</tr>\n<tr>\n<td>x-cos-meta-*</td>\n<td>The header information allowed to be defined by users, which is returned as the object’s metadata. The size is limited to 2 KB</td>\n</tr>\n<tr>\n<td>x-cos-storage-class</td>\n<td>Sets the storage class of the object. Enumerated values: STANDARD, STANDARD_IA, ARCHIVE. Default value: STANDARD</td>\n</tr>\n<tr>\n<td>x-cos-server-side-encryption</td>\n<td>Indicates whether server-side encryption is enabled for the object. If you use a COS master key for encryption, enter AES256</td>\n</tr>\n</tbody>\n</table>\n\n### Object Sub-resources\n\nCOS has sub-resources that are associated with buckets and objects. Sub-resources belong to objects, so they do not exist independently; instead, they are always associated with other entities such as objects or buckets. An access control list (ACL) is the access control information list for a specific object, which is a sub-resource of a COS object.\n\nAn ACL contains an authorization list that identifies authorized users and the granted permissions to implement access control on the object. When you create an object, ACL identifies the object owner who can fully control the object. You can retrieve the object ACL or replace it with a new authorization list.\n\nTo update an ACL, you can only do so by replacing it.\n\n### Access Permission Types\n\nCOS supports setting two types of permissions to objects: public permissions and user permissions.\n\n**Public permissions:** Including inherited permission, Private Read/Write, and Public Read/Private write.\n\n- Inherited permission: The object permissions inherited from the bucket is the same as the access permissions of the bucket itself. When you access an object with the “inherited bucket permission”, COS will match the bucket permission to respond to the access. A new object inherits the permission from its bucket by default.\n- Private Read/Write: When you access an object with the Private Read/Write permission, the object can only be accessed with a request signature, regardless of the bucket permission.\n- Public Read/Private Write: When you access an object with the Public Read permission, the object can be directly downloaded, regardless of the bucket permission.\n\n**User permissions:** The root account has all the permissions of the object by default (i.e., full control). In COS, sub-accounts can be added to Read/Write data, Read/Write permissions, and have the full control permission.\n\n**Use Cases**\n\nAllow public access to a specified object in a Private Read/Write bucket or set a required authentication for a specific object in a Public Read/Write bucket.\nCOS offers three object storage classes for different object access frequencies: standard storage, standard infrequent access storage, and archive storage.\n\nWhen an object is uploaded, if the storage class is not set, it defaults to **standard storage**.\n\n### Standard Storage\n\nStandard storage (Standard) provides object storage services featuring high reliability, availability, and performance. It offers low access latency and high throughput, making it suitable for business scenarios where a large number of trending files is accessed in real time with frequent data interactions.\n\n**Features**\n- High performance and availability\n- Data persistence: 99.999999999%\n- Service availability: 99.95%\n- Response: Within milliseconds\n- Supported regions: All\n- Storage cost: Standard\n\n**Use Cases**\n- Trending videos, social networking photos, mobile apps, games, and dynamic websites.\n\n### Standard Infrequent Access Storage\n\nStandard infrequent access storage (Standard_IA) provides object storage services featuring high reliability and low storage cost and access latency. It offers lowered pricing for storage and keeps the first-byte access time within milliseconds, ensuring that data can be fast retrieved with no wait required. However, data retrieval incurs fees. It is suitable for business scenarios where the access frequency is low (e.g., once or twice per month).\n\n**Features**\n- Low-frequency access, real-time response\n- Data persistence: 99.999999999%\n- Service availability: 99.9%\n- Minimum billing duration: 30 days\n- Minimum object size: 64 KB\n- First-byte delay: Within milliseconds\n- Supported regions: All\n- Storage cost: Low\n\n**Use Cases**\n- Online file storage, big data analytics, governmental/organizational business data, low-frequency archives, and monitoring data.\nArchive Storage\n\nArchive storage (Archive) provides objects storage services featuring high reliability, extremely low storage cost, and long-term retention.\n\nIt offers the lowest unit price of storage but requires a longer unfreezing time when data is read, making it suitable for archived data that needs to be retained for a long time.\n\n**Features**\n\n- High data persistence and service availability, low cost\n- Data persistence: 99.999999999%\n- Service availability: 99.9%\n- Minimum billing duration: 90 days\n- Minimum object size: 64 KB\n- Response: Prior application for data restoration required\n- Supported regions: Public cloud regions only\n- Storage cost: Very low\n\n**Use Cases**\n\nArchive of compliance documents (e.g., archival data, medical images, and scientific materials), lifecycle files, operational logs, and remote disaster recovery.\n\n**Comparison of Storage Types**\n\n<table>\n<thead>\n<tr>\n<th>Item</th>\n<th>Standard</th>\n<th>Standard_IA</th>\n<th>Archive</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Data persistence</td>\n<td>99.999999999%</td>\n<td>99.999999999%</td>\n<td>99.999999999%</td>\n</tr>\n<tr>\n<td>Service availability</td>\n<td>99.95%</td>\n<td>99.9%</td>\n<td>99.9%</td>\n</tr>\n<tr>\n<td>Response</td>\n<td>Within milliseconds</td>\n<td>Within milliseconds</td>\n<td>Prior application for data restoration required</td>\n</tr>\n<tr>\n<td>Minimum object size</td>\n<td>Calculated by actual object size</td>\n<td>64 KB</td>\n<td>64 KB</td>\n</tr>\n<tr>\n<td>Minimum billing duration</td>\n<td>No limit</td>\n<td>30 days</td>\n<td>90 days</td>\n</tr>\n<tr>\n<td>Supported regions</td>\n<td>All</td>\n<td>All</td>\n<td>Public cloud regions only</td>\n</tr>\n<tr>\n<td>Storage cost</td>\n<td>Standard</td>\n<td>Low</td>\n<td>Very low</td>\n</tr>\n<tr>\n<td>Data retrieval cost</td>\n<td>None</td>\n<td>Low</td>\n<td>High</td>\n</tr>\n<tr>\n<td>Read/write request cost</td>\n<td>Very low</td>\n<td>Low</td>\n<td>Very low (data needs to be restored to standard storage)</td>\n</tr>\n</tbody>\n</table>\nUploading Object\nSimple Upload\n\nLast updated : 2019-11-13 15:11:08\n\nUse Cases\n\nThis operation is suitable for uploading an object smaller than 5 GB in a single request. For objects larger than 5 GB, you must use the multipart upload method.\n\nIf your object is large (for example, 100 MB), it is recommended that you use multipart upload in a high-bandwidth or weak network environment.\n\nDirections\n\nVia the COS Console\nYou can upload an object in the COS Console. For more information, see Uploading an Object in Console Guide.\n\nVia REST API\nYou can use the REST API directly to initiate a simple object upload request. For more information, see PUT Object.\n\nVia the SDK\nYou can directly call the simple object upload method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\nMultipart Upload\n\nUse Cases\n\nMultipart upload is well suited for uploading large objects in weak network or high-bandwidth environments. The COS Console and SDKs can break a single object into multiple parts and then upload them. You can also do so by yourself and upload each part through API calls. Multipart upload has the following benefits:\n\n- In a weak network, smaller part size minimizes the impact of restarting a failed upload due to network errors.\n- In a high-bandwidth environment, multipart upload can maximize the use of your available bandwidth by uploading object parts in parallel. Uploading parts out of order does not affect the final merged object.\n- With multipart upload, you can pause and resume the upload of a single large object at any time. All incomplete multipart uploads can be resumed unless aborted.\n- Multipart upload can also be used to begin an upload before you know the final object size. You can initiate an upload and then merge the parts to get the full object size.\n\nWhen uploaded, the parts are numbered consecutively. You can upload each part separately or upload them in any order. COS will merge the parts into an object based on their numbers. If the upload of any part fails, the failed part can be uploaded again without affecting other parts and the content as a whole. In a weak network environment, multipart upload is recommended for objects larger than 20 MB. In a high-bandwidth environment, multipart upload is recommended for objects larger than 100 MB.\n\nDirections\n\nVia REST API\n\nYou can use the REST API directly to initiate a multipart upload request. For more information, see the following API documents:\n\n- Initiate Multipart Upload\n- Upload Part\n- Complete Multipart Upload\n- Abort Multipart Upload\n\nVia the SDK\n\nYou can directly call the multipart upload method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\nUpload via Pre-Signed URL\n\nUse Cases\n\nAll buckets and objects are private by default. If you want a third party to be able to upload an object to your bucket but don't want them to use CAM account or temporary keys, signatures can be provided by pre-signed URLs for temporary upload operations. Anyone who receives a valid pre-signed URL can upload an object.\n\nWhen creating a pre-signed URL, you can include an object key in your signature so that the object can only be uploaded to the specified object key. Besides, the validity period of pre-signed URLs can be provided in SDKs to ensure that expired URLs will not be used by any unauthorized party.\n\nDirections\n\nVia the SDK\n\nYou can call the pre-signed URL method in the SDK directly. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\nObtaining Object\n\nObtaining Object Simply\n\nUse Cases\n\nYou can initiate a request to obtain objects directly in COS. You have the following options when obtaining an object:\n\n- Obtain a complete object: Obtain the complete object data directly by initiating a GET request.\n- Obtain a part of an object: Use the Range request header in a GET request to retrieve a specific range of bytes of an object. Retrieving multiple ranges is not supported.\n\nThe object’s metadata will be returned along with the object’s content as an HTTP response header. The GET request supports overwriting certain metadata values in the response using URL parameters. For example, the response value of Content-Disposition can be overwritten. Response headers that support modification include:\n\n- Content-Type\n- Content-Language\n- Expires\n- Cache-Control\n- Content-Disposition\n- Content-Encoding\n\nDirections\n\nVia the COS Console\n\nYou can obtain an object in the COS Console. For more information, see Downloading Objects in Console Guide.\n\nVia REST API\n\nYou can use the REST API directly to initiate an object obtaining request. For more information, see GET Object.\n\nVia the SDK\n\nYou can directly call the object download method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\nUse Cases\n\nAll buckets and objects are private by default. If you want any third party to be able to download an object without using CAM account or temporary keys, provide the third parties with signatures via pre-signed URLs for download operations. Anyone who receives a valid pre-signed URL can download an object.\n\nWhen creating a pre-signed URL, you can include object keys in your signature to specify the objects allowed for download. Besides, the validity period of pre-signed URLs can be provided in SDKs to ensure that expired URLs will not be used by any unauthorized party.\n\nDirections\n\nVia the SDK\n\nYou can call the pre-signed URL method in the SDK directly. For more information, see the SDK documentations for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\nListing Object Keys\n\nUse Cases\n\nTencent Cloud COS supports listing keys by prefix. You can use the separator (/) in a key to implement a hierarchical structure similar to the traditional file system. In COS, you can use separators to select and browse keys hierarchically.\n\nYou can list all keys in a single bucket in UTF-8 binary order of prefixes or filter the key list by specifying the prefix. For example, adding the parameter \\texttt{t}, would list the \\texttt{tencent} object, while skipping objects prefixed with \\texttt{a} or other characters.\n\nKeys can be reorganized based on the added separator (/). You can use the prefix and separator together to implement a folder retrieval feature. For example, if you add the prefix parameter \\texttt{t} and the separator (/), eligible keys such as \\texttt{tencent/cos} will be listed.\n\nCOS supports storing an unlimited number of objects in a single bucket, so the key list may be very large. For management purposes, a maximum of 1,000 key values are returned for one List Objects request, and a marker will be returned to indicate whether the result is truncated. You can send a series of List Objects requests based on markers and separators to list all key values or search for the desired content.\n\nDirections\n\nVia REST API\n\nYou can use the REST API directly to initiate an object key listing request. For more information, see \\texttt{GET Bucket}.\n\nVia the SDK\n\nYou can directly call the object list querying method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- [SDK for Android]\n- [SDK for C]\n- [SDK for C++]\n- [SDK for .NET]\n- [SDK for Go]\n- [SDK for iOS]\n- [SDK for Java]\n- [SDK for JavaScript]\n- [SDK Node.js]\n- [SDK for PHP]\n- [SDK for Python]\n- [SDK for WeChat Mini Program]\nCopy Objects\n\nUse Cases\n\nThe copy operation creates a copy of an object that is already stored in COS. You can create a copy of your object up to 5 GB in a single operation. To copy an object over 5 GB, you must use the multipart upload API. With the copy operation, you can:\n\n- Create a copy of an object.\n- Rename the object by copying it and deleting the original one.\n- Modify the storage class of the object. In the copy operation, you can select the same object key as both the source and destination and modify the storage class.\n- Copy objects across different COS regions.\n- Modify object metadata. In the copy operation, you can select the same object key as both the source and destination and modify object metadata.\n\nIn the copy operation, the metadata of the original object is inherited by default, but the creation date is subject to the new object.\n\nDirections\n\nVia REST API\n\nYou can use the REST API directly to initiate an object copying request. For more information, see PUT Object - Copy.\n\nVia the SDK\n\nYou can directly call the object copying method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for PHP\n- SDK for Python\nMultipart Copy\n\nUse Cases\n\nFor copying an object greater than 5 GB, you must use the multipart copy. Use the multipart upload API to create an object, and use the Upload Part - Copy API to carry the x-cos-copy-source header to specify the source object. The process is as follows:\n\n1. Initialize an object for multipart upload.\n2. Copy the data of the source object. You can specify the x-cos-copy-source-range header and copy up to 5 GB of data at a time.\n3. Complete the multipart upload.\n\nSDKs provided by COS can be used to easily implement multipart copy.\n\nDirections\n\nVia REST API\n\nYou can use the REST API directly to initiate a multipart copy request. For more information, see the following API documentations:\n\n- Initiate Multipart Upload\n- Upload Part - Copy\n- Complete Multipart Upload\n- Abort Multipart Upload\n\nVia the SDK\n\nYou can call the multipart copy method in the SDK directly. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C++\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\nDeleting Object\nDeleting a Single Object\n\nUse Cases\n\nCOS supports deleting one or multiple objects directly. To delete one object, you only need to provide its object key and call an API request to delete it.\n\nDirections\n\nVia the COS Console\nYou can delete an object in the COS Console. For more information, see Deleting an Object in Console Guide.\n\nVia REST API\nYou can use the REST API directly to initiate a single object deleting request. For more information, see DELETE Object.\n\nVia the SDK\nYou can directly call the single object deleting method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\n- SDK for WeChat Mini Program\nDeleting Multiple Objects\n\nUse Cases\n\nCOS supports batch deletion of multiple objects. You can delete objects in batches via the console, APIs, and SDKs.\n\nBy default, when the deletion task is completed, a null will be returned. If an error occurs, an error message will be returned.\n\nA maximum of 1,000 objects can be deleted in a single request. To delete more objects, split the list and send the request separately.\n\nDirections\n\nVia the COS Console\n\nYou can delete multiple objects in batches in the COS Console. For more information, see Deleting an Object in Console Guide.\n\nVia REST API\n\nYou can use the REST API directly to initiate a multiple objects deleting request. For more information, see DELETE Multiple Objects.\n\nVia the SDK\n\nYou can directly call the multiple objects deleting method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for Go\n- SDK for iOS\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\nData Management\n\nInventory Overview\n\nLast updated: 2019-12-17 12:42:00\n\nWhat Is Inventory\n\nInventory is a feature that helps users manage bucket objects. It operates periodically and as an alternative to the COS synchronous List API operation. COS can daily or weekly scan a specified object or objects with a same prefix in a bucket based on an inventory task configured by the user, and export and store an inventory report as a CSV file in the bucket specified by the user. The file lists stored objects and corresponding metadata, and records the desired object attribute information based on the configuration.\n\nYou can use the inventory feature for various purposes, including but not limited to:\n\n- Review and report replication and encryption states of an object.\n- Streamline and speed up service workflows and big data jobs.\n\n- You can configure multiple inventory tasks for one bucket. COS doesn’t directly read the content of an object, but only scan the attribute information such as metadata of the object.\n- Currently, the inventory feature is not available for COS buckets in financial cloud regions and outside China regions.\n\nInventory Parameters\n\nAfter you configure an inventory task for a bucket, COS regularly scans a specified object in the bucket based on your configuration, and exports an inventory report in .csv format. Currently, the inventory report can record the following information:\n\n<table>\n<thead>\n<tr>\n<th>Inventory Information</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AppID</td>\n<td>Account ID</td>\n</tr>\n<tr>\n<td>Bucket</td>\n<td>Name of the bucket for which an inventory task is executed.</td>\n</tr>\n<tr>\n<td>Key</td>\n<td>Name of an object file in a bucket. When using the CSV file format, the key name is URL-encoded and must be decoded before you can use it.</td>\n</tr>\n<tr>\n<td>VersionId</td>\n<td>Version ID of an object. After version control is enabled for a bucket, COS specifies a version ID for the object added to the bucket. If the list is for the current version only, the inventory does not include this field.</td>\n</tr>\n<tr>\n<td>IsLatest</td>\n<td>Sets to True if the latest object version is used. This field is not included if the list is only for the current version of objects.</td>\n</tr>\n<tr>\n<td>IsDeleteMarker</td>\n<td>Sets to True if the object is a delete marker. This field is not included if the list is only for the current version of objects.</td>\n</tr>\n<tr>\n<td>Size</td>\n<td>Size of an object (in bytes)</td>\n</tr>\n<tr>\n<td>LastModifiedDate</td>\n<td>Last modified date of an object (the most recent date prevails)</td>\n</tr>\n<tr>\n<td>ETag</td>\n<td>Hash value of an object. It displays only modification to the content of an object, rather than to its metadata. The ETag may be or may not be the MD5 checksum of the data of the object, and this depends on how the object is created and encrypted.</td>\n</tr>\n<tr>\n<td>Inventory Information</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-----------------------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>StorageClass</td>\n<td>Storage class of the object. For more information, see Storage Class</td>\n</tr>\n<tr>\n<td>IsMultipartUploaded</td>\n<td>Sets to True if the object is uploaded in multiple parts. For more information, see Multipart Upload</td>\n</tr>\n<tr>\n<td>Replicationstatus</td>\n<td>Sets to PENDING, COMPLETED, FAILED, or REPLICA. For more information, see Replication Behavior Descriptions</td>\n</tr>\n</tbody>\n</table>\n\n### How to Configure the Inventory\n\nBefore configuring the inventory, you need to understand two concepts:\n\n- **Source bucket**: The bucket for which the inventory is to be enabled\n - Includes the objects listed in the inventory\n - Includes the configurations of the inventory\n\n- **Destination bucket**: The bucket where the inventory list file is stored\n - Includes files in the inventory list\n - Includes the manifest files describing the location of the inventory list\n\nTo configure the inventory, do the following steps:\n\n**Specifying Information about Objects to Be Analyzed in the Source Bucket**\n\nTo inform COS of object information to be analyzed, you need to configure the following information in the source bucket for the inventory:\n\n- **Select object versions**: List all the versions of the object or list only the current version. If you select to list all the versions of the object, COS adds information about the object in all historical versions to the inventory report. If you select to list only the current version, COS records only the object in the latest version.\n\n- **Specify the object attributes to be analyzed**: You need to inform COS of object attributes that need to be recorded in the inventory report. Currently, the following object attributes are supported: account ID, name of the source bucket, name of the object file, version ID of the object, whether it is the latest version, whether a delete marker is included, size of the object, last modified date of the object, ETag, storage class, cross-region replication marker, and whether the object is uploaded in multiple parts.\n\n**Configuring the Storage Information for the Inventory Report**\n\nYou need to inform COS of an export frequency of the inventory report, a bucket used to store the inventory report, and whether the inventory report needs to be encrypted. Please see the configuration details as below:\n\n- **Select an export frequency**: Daily or weekly. COS will execute the inventory feature at the specified frequency.\n\n- **Select an encryption mode**: No encryption or SSE-COS. If SSE-COS is selected, COS encrypts the generated inventory report.\n\n- **Configure an export location**: You need to specify the bucket to store the inventory report.\n\nThe destination bucket and the source bucket need to be located in a same region and may be a same bucket.\n\n### Usage\n\n**Configuring the Inventory via Console**\nTo learn how to configure the inventory via Console, see Enabling Inventory in the console documentation.\n\n**Configuring the Inventory via APIs**\n\nTo learn how to configure the inventory via APIs, see the following API Documentation:\n\n- PUT Bucket inventory\n- GET Bucket inventory\n- DELETE Bucket inventory\n- List Bucket inventory Configurations\n\n**Storage Path for the Inventory Report**\n\nThe inventory report and related manifest files are published in the destination bucket. The inventory report is published in the following path:\n\n```\ndestination-prefix/source-bucket/config-ID/data/\n```\n\nThe related manifest files are published in the following file of the destination bucket:\n\n```\ndestination-prefix/source-bucket/config-ID/YYYY-MM-DD-HH-MM/manifest.json\ndestination-prefix/source-bucket/config-ID/YYYY-MM-DD-HH-MM/manifest.checksum\n```\n\nMeaning of the path is as follows:\n\n- **destination-prefix**: \"Destination Prefix\" set by the user during configuration of the inventory. It may be used to group all inventory reports in a public location in the destination bucket.\n- **source-bucket**: Name of the source bucket corresponding to the inventory report. This folder is intended to prevent possible conflicts when inventory reports from multiple source buckets are sent to a same destination bucket.\n- **config-ID**: \"Inventory Name\" set by the user during configuration of the inventory. When multiple inventory reports are set for a same source bucket and sent to a same destination bucket, you can specify config-ID to distinguish between the different inventory reports.\n- **YYYY-MM-DD-HH-MM**: Timestamp, including the time and the date when the bucket starts to be scanned during generation of the inventory report.\n- **manifest.json**: Manifest file.\n- **manifest.checksum**: MD5 of the content of the manifest.json file.\n\nThe related manifest files include two files: manifest.json and manifest.checksum.\n\nThe following describes the related manifest files:\n\n- Both manifest.json and manifest.checksum are manifest files. manifest.json describes the location of the inventory report, and manifest.checksum is the MD5 of manifest.json. Each newly delivered inventory report comes with a set of new manifest files.\n- Each manifest included in manifest.json provides metadata and other basic information related to the inventory. The information includes:\n - Name of the source bucket\n - Name of the destination bucket\n - Inventory version\n - Timestamp, including the date and the time when the bucket starts to be scanned during generation of the inventory report.\n - Format and architecture of the inventory file\n - Object key, size, and MD5 checksum of the inventory report in the destination bucket.\nThe following shows an example of the manifest content in the manifest.json file in .csv format:\n\n```json\n{\n \"sourceBucket\": \"example-source-bucket-1250000000\",\n \"destinationBucket\": \"example-inventory-destination-bucket-1250000000\",\n \"fileFormat\": \"CSV\",\n \"fileSchema\": \"Bucket, Key, Size, StorageClass, ETag, ReplicationStatus, MultipartUploaded, LastModifiedDate, VersionId, IsLatest, IsDeleteMarker\",\n \"files\": [\n {\n \"key\": \"destination-prefix/example-source-bucket-1250000000/config-ID/data/939c6d46-85a9-4ba8-87bd-9db705a579ce.csv.gz\",\n \"size\": 2147483647,\n \"MD5checksum\": \"f11166068f1990abe9c97ace9c9eabc\"\n }\n ]\n}\n```\n\n**Inventory Consistency**\n\nAll of your objects might not appear in each inventory list. The inventory list provides eventual consistency for PUTs of both new objects and overwrites, and DELETEs. Therefore, the inventory report possibly does not include the latest added or deleted object. For example, if the user uploads or deletes an object when COS is executing an inventory task configured by the user, the results of the upload or deletion operations may be not reflected in the inventory report.\n\nTo validate the status of the object before COS performs an operation, you can search for the metadata of the object by using the HEAD Object API, or check the attributes of the object in COS Console.\nBucket Tag Overview\n\nOverview\nA bucket tag is a key-value pair (key = value), which is comprised of a tag key and a tag value that are connected by an equal sign (\"=\"), for example: group = IT. It can be used to identify a bucket, helping you achieve group management of buckets. You can set, query, and delete the tag for a specified bucket.\n\nSpecifications and Limits\n\nLimits on Tag Keys\n- A tag key starting with \"qcs:\" or \"project\" is a default tag key and cannot be changed.\n- A tag key can only contain characters encoded in UTF-8, spaces, numbers, or special characters including +, -, =, ., _, :, /, @.\n- A tag key should be a combination of 0-127 characters encoded in UTF-8.\n- Tag keys are case sensitive.\n\nLimits on Tag Values\n- A tag value can only contain characters encoded in UTF-8, spaces, numbers, or special characters including +, -, =, ., _, :, /, @.\n- A tag value should be a combination of 0-255 characters encoded in UTF-8.\n- Tag values are case sensitive.\n\nLimits on the Number of Tags\n- Bucket dimension: A resource has at most 10 different bucket tags.\n- Tag dimension:\n - A user has at most 1,000 different keys.\n - A key has at most 1,000 values.\n - Multiple same keys are not allowed in the same bucket.\n\nUsage\nYou can set bucket tags via the console or APIs.\n\nVia the COS Console\nFor more information on how to set a bucket tag using the COS Console, see Setting Bucket Tags in Console Guide.\n\nVia REST APIs\nYou can directly manage bucket tags using the following APIs:\n- PUT Bucket tagging\n- GET Bucket tagging\n- DELETE Bucket tagging\nLifecycle Management\n\nLifecycle Overview\n\nCOS supports object-based lifecycle configuration. By sending specific description language to a bucket, COS can automatically perform predefined actions on objects to which a rule is applied.\n\nA lifecycle can be set to as long as 3,650 days.\n\nUse Cases\n\nLog Record\nWith corresponding lifecycle configuration, log data stored in COS can be automatically archived after 30 days or deleted after 2 years.\n\nData Transition\nHot data is frequently accessed in a short period of time after the upload, but then is less or not accessed at all after some time. Therefore, you may set the lifecycle rules to store the data uploaded 30 days ago in Standard_IA storage class and store the data uploaded 60 days ago in Archive storage class. This process is called data transition.\n\nArchive Management\nWhen you use COS for file archive management, you need to save all historical versions of files for a long time in accordance with compliance requirements in financial, medical, and other industries. In this case, you can configure the lifecycle to transition and store the historical versions of files in Archive storage class.\n\nSupport Descriptions\n\nSupported Actions\n- Data transition: transition objects to Standard_IA or Archive storage class after a specified period of time.\n- Deletion after expiration: automatically delete objects after their specified expiration time.\n\nSupported Resources\n- Specified based on prefixes: objects with different prefixes are processed according to applicable rules.\n- Versioning-enabled objects: you can manage the current and historical versions of objects separately as needed.\n- Objects with delete markers: when all old versions of objects are cleared, you can specify to remove their delete markers.\n- Incomplete multipart uploads: process incomplete multipart upload tasks.\n\nSupported Time Conditions\n- Based on the number of days: specify in how many days after an object is last modified the corresponding action will be performed.\n- Based on a specific date: specify a date when the corresponding action will be performed.\n\nNotes\n\nData Transition\nSupported Regions\n\nData transition to the Archive storage class is supported in public cloud regions.\n\nOne-way Transition\n\nData transition is one-way (from Standard storage to Standard_IA storage to Archive storage or from Standard storage to Archive storage) and cannot be in the reversed way. You can only call PUT Object - Copy (for non-archive storage classes) or POST Object restore (for Archive storage class only) to restore data from a colder storage class to a hotter class.\n\nEventual Consistency\n\nIf multiple conflicting rules (excluding deletion after expiration) are configured for the same set of objects, these rules will be performed in a chronological order. The objects will be transitioned to the coldest storage class according to the rules.\n\nDeletion after Expiration\n\nHow it Works\n\nWhen an object matches the specified lifecycle rule of deletion after expiration, COS will add it to the async deletion queue. There will be a delay in the actual deletion. You can get the current status of the object by performing a GET or HEAD Object operation.\n\nEventual Consistency\n\nIf multiple conflicting rules are configured for the same set of objects, these rules will be performed in chronological order in accordance with expiration time. Deletion after expiration takes precedence over before transition from one storage class to another.\n\nCost Considerations\n\nExecution Instructions\n\nOnce triggered, actions configured at any time will always be executed at 00:00 Beijing time (GMT+8) the next day in COS. As objects need to be added to an async queue before execution, for objects uploaded after the configuration time that are matched by a rule, actions will be performed on them before 00:00 the next day.\n\nWhen any accident occurs or there are too many objects in the bucket, lifecycle execution may fail. For failures due to other reasons, execute GET or HEAD Object to get the current object status.\n\nTencent Cloud cannot provide an accurate bill unless the lifecycle execution is completed.\n\nTime-insensitivity\n\nPlease note that the minimum storage duration in Standard_IA or Archive storage class is 30 or 60 days, respectively; otherwise, additional storage fees will be incurred upon data transition or deletion. COS will not check lifecycle configurations less than 30/60 days; therefore, it will execute correct configurations upon your request.\n\nFor example, if an object in Standard_IA storage class is transitioned before it is stored for 30 days, it will start incurring Archive storage fees on the transition day and continue incurring Standard_IA storage fees until the 30th day.\n\nAnother example is that if an archived object is deleted upon expiration before it is stored for 60 days, it will continue incurring Archive storage fees until the 60th day.\nSize-insensitivity\n\nThere are minimum object size requirements in both the Standard_IA and Archive storage classes. For example, if an object below 64 KB is uploaded to the Standard_IA storage class, it will be calculated as 64 KB. COS will not check the file size; instead, it will perform object conversion operations unconditionally according to the specified rule.\nElements of Lifecycle Configuration\n\nLast updated: 2019-06-14 18:46:43\n\nBasic Structure\n\nA lifecycle configuration is specified as XML and consists of one or more lifecycle rules. The structure is as follows:\n\n```xml\n<LifecycleConfiguration>\n <Rule>\n <ID>**your lifecycle name**</ID>\n <Status>Enabled</Status>\n <Filter>\n <And>\n <Prefix>projectA/</Prefix>\n <Tag>\n <Key>key1</Key>\n <Value>value1</Value>\n </Tag>\n </And>\n </Filter>\n **transition/expiration actions**\n </Rule>\n ...\n</LifecycleConfiguration>\n```\n\nEach rule contains the following:\n\n- **ID** (optional): Indicates the content of the rule and is customizable.\n- **Status**: Indicates whether the rule is enabled or disabled.\n- **Filter**: Identifies objects to which the rule applies.\n- **Action**: Actions that need to be performed on objects that match the above description.\n- **Time**: `Days` (calculated from the date when an object is last modified) or `Date` based on which actions are performed on objects.\n\nRule Description\n\nFilter element\n\nFor all objects in a bucket\n\nYou can specify an empty filter, in which case the rule applies to all objects in the bucket.\n\n```xml\n<LifecycleConfiguration>\n <Rule>\n <Filter/>\n <Status>Enabled</Status>\n **transition/expiration actions**\n </Rule>\n</LifecycleConfiguration>\n```\n\nBased on object key prefixes\n\nSpecify a prefix-based filter so that a rule applies only to objects with specific prefixes. For example, you can filter out objects based on the prefix `logs/`:\n\n```xml\n<LifecycleConfiguration>\n <Rule>\n <Filter>\n <Prefix>logs/</Prefix>\n </Filter>\n <Status>Enabled</Status>\n **transition/expiration actions**\n </Rule>\n</LifecycleConfiguration>\n```\nElements to describe actions\n\nYou can specify one or more predefined actions in a lifecycle rule so that these actions are performed when any objects meet the rule.\n\nTransition action\n\nSpecify the Transition action to transition objects from one storage class to another. For a versioned bucket, the Transition action applies to the current object version. You can set the transition date to as short as 0 day. For example, transition objects to Archive Storage after 30 days:\nDeletion after expiration\n\nSpecify the Expiration action to delete expired objects. For a non-versioned bucket, expired objects will be permanently deleted. For a versioned bucket, expired objects are added with DeleteMarker and become the current version. For example, delete objects with an expiration of 30 days:\n\n```\n<Expiration>\n <Days>30</Days>\n</Expiration>\n```\n\nIncomplete Multipart Upload\n\nSpecify the AbortIncompleteMultipartUpload action to delete multipart upload tasks with specific UploadId if they are not successfully completed within the predefined time period. In this case, these tasks also cannot be resumed or indexed. For example, abort multipart upload tasks not successfully completed within 7 days:\n\n```\n<AbortIncompleteMultipartUpload>\n <Days>7</Days>\n</AbortIncompleteMultipartUpload>\n```\n\nObjects of non-current versions\n\nIn a versioned bucket, Transition action only applies to objects of the latest version and Expiration action only results in adding deletion markers to the objects. Therefore, Tencent Cloud COS provides the following actions to objects of non-current version:\n\nSpecify the NoncurrentVersionTransition action to transition the current version of objects to another storage class at a specified time. For example, transition the non-current versions of objects to Archive Storage after 30 days:\n\n```\n<NoncurrentVersionTransition>\n <StorageClass>ARCHIVE</StorageClass>\n <Days>30</Days>\n</NoncurrentVersionTransition>\n```\n\nSpecify the NoncurrentVersionExpiration action to delete the current version of objects expired at a specified time. For example, delete the non-current versions of objects expired after 30 days:\n\n```\n<NoncurrentVersionExpiration>\n <Days>30</Days>\n</NoncurrentVersionExpiration>\n```\n\nWhen all non-current object key versions are deleted and the current object version is DeleteMarker, specify the ExpiredObjectDeleteMarker action to delete the DeleteMarker. For example, delete the DeleteMarker of the expired objects after 31 days:\n\n```\n<ExpiredObjectDeleteMarker>\n <Days>31</Days>\n</ExpiredObjectDeleteMarker>\n```\n\nTime element\n\nBased on number of days\nDays refers to the number of days since an object was last modified. For example, if an object is set to be transitioned to Archive Storage after 0 day, when the object is uploaded at 2018-01-01 23:55:00 GMT+8, it will be added to the transition queue at 2018-01-02 00:00:00 GMT+8 and transitioned before 2018-01-02 23:59:59 GMT+8.\n\nFor example, if an object is set to be deleted after 1 day due to expiration, when the object is uploaded at 2018-01-01 23:55:00 GMT+8, it will be added to the expiration queue at 2018-01-03 00:00:00 GMT+8 and deleted before 2018-01-03 23:59:59 GMT+8.\n\n**Based on a specific date**\n\nPerform the predefined action to all qualified objects based on the filter criteria at the specific date. The date value must conform to the ISO 8601 format. The time is always 00:00 GMT+8.\n\nFor example, use `2018-01-01T00:00:00+08:00` for January 1, 2018.\nConfiguring Lifecycle\n\nUse Cases\n\nWith lifecycle configuration, certain predefined actions can be automatically performed when a rule is applied to objects. For example:\n\n- Transition: transition objects to STANDARD_IA storage or ARCHIVE storage after a specified time of period.\n- Expiration: automatically delete objects after their specified expiration time.\n\nFor more information, see Lifecycle Overview and Elements of Lifecycle Configuration.\n\nDirections\n\nVia the COS Console\n\nYou can configure the lifecycle in the COS Console. For more information, see Lifecycle Management in Console Guide.\n\nVia REST API\n\nYou can configure and manage the lifecycle of objects in a bucket through the REST API as described in the following API documentations:\n\n- PUT Bucket lifecycle\n- GET Bucket lifecycle\n- DELETE Bucket lifecycle\n\nVia the SDK\n\nYou can directly call the lifecycle method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- SDK for Android\n- SDK for C\n- SDK for C++\n- SDK for .NET\n- SDK for Go\n- SDK for iOS\n- SDK for Java\n- SDK for JavaScript\n- SDK for Node.js\n- SDK for PHP\n- SDK for Python\nStatic Website Hosting\n\nLast updated: 2019-07-01 16:04:40\n\nBasic Concepts\n\nA static website is a website that contains static content (such as HTML) or client scripts. Users can configure static websites for buckets with a custom domain name through the console. A dynamic website contains server scripts such as PHP, JSP, or ASP.NET, and needs to be processed on a server. You can host static websites on Tencent Cloud COS, but cannot write server scripts. When deploying a dynamic website, you are recommended to use a CVM for server code deployment.\n\nExample\n\nA user created a bucket named examplebucket-1250000000 and uploaded the following file:\n\n```\nindex.html\n404.html\n403.html\ntest.html\ndocs/a.html\nimages/\n```\n\n**Static website**\n\n**Before enabled:** Access the bucket via the following default domain name. When a download prompt pops up, save the `index.html` file to the local.\n\n```\n```\n\n**After enabled:** Access the bucket via the following access node, and then you can view the content of `index.html` directly in the browser.\n\n```\n```\n\n**Forced HTTPS**\n\n**Before enabled:** When the request source is HTTP, the access node URL keeps the HTTP unencrypted transport protocol:\n\n```\nhttp://examplebucket-1250000000.cos-website.ap-guangzhou.myqcloud.com\n```\n\n**After enabled:** The access node always maintains the HTTPS encrypted transport protocol regardless of whether the request source is HTTP or HTTPS:\n\n```\nhttps://examplebucket-1250000000.cos-website.ap-guangzhou.myqcloud.com\n```\n\n**Index document**\n\nAn index file, the homepage of the static website, is a page returned when the root directory or any subdirectory of a website is requested, and is usually named `index.html`.\n\nWhen you access a static website via a bucket access domain name, such as `https://examplebucketbucket-1250000000.cos-website.ap-guangzhou.myqcloud.com`, and no specific page is requested, the Web server will return the homepage.\nWhen your user accesses any directory (including the root directory) in a bucket using a URL ended with `/`, the index document in that directory is matched automatically. `/` is not mandatory in the root URL, so the index document is returned in response to either of the following URLs.\n\n- http://www.examplebucket.com/\n- http://www.examplebucket.com\n\nIf a folder is created in the bucket, the index file needs to be added at each level of the folder.\n\n### Error document\n\nSuppose that when you visit the following page before configuring the error document, a 404 status code is returned, and the default error information displays in the page.\n\nhttps://examplebucket-1250000000.cos-website.ap-guangzhou.myqcloud.com/webpage.html\n\nWhen you visit the following page after configuring the error document, a 404 status code is also returned, but the specific error information displays in the page.\n\nhttps://examplebucket-1250000000.cos-website.ap-guangzhou.myqcloud.com/webpage.html\n\n### Redirection rules\n\n#### Configure error code redirection\n\nIf the webpage.html document is set to Private Read/Write, when a user tries to access it, a 403 error is returned. After the 403 error code is redirected to 403.htm, the browser will return the content of 403.html.\n\nIf you do not configure a 403.html document, the browser will return an error document or default error message.\n\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Description</th>\n<th>Force HTTPS</th>\n<th>Rule</th>\n<th>Replace content</th>\n<th>Actions</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Http error code</td>\n<td>403</td>\n<td></td>\n<td>Replace path</td>\n<td>403.html</td>\n<td>Delete</td>\n</tr>\n</tbody>\n</table>\n\n#### Configure prefix match\n\n1. When you rename a folder from `docs/` to `documents/`, the user will get an error when accessing the `docs/` folder. So, you can redirect the request with the prefix `docs/` to `documents/`.\n\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Description</th>\n<th>Force HTTPS</th>\n<th>Rule</th>\n<th>Replace content</th>\n<th>Actions</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Prefix matching</td>\n<td><code>docs/</code></td>\n<td></td>\n<td>Replace prefix</td>\n<td><code>documents/</code></td>\n<td>Delete</td>\n</tr>\n</tbody>\n</table>\n\n2. When you delete the `images/` folder (i.e., deleting all objects with the prefix `images/`), you can add a redirection rule to redirect requests for any object with the prefix `images/` to `test.html`.\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Description</th>\n<th>Force HTTPS</th>\n<th>Rule</th>\n<th>Replace content</th>\n<th>Actions</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Prefix matching</td>\n<td>images/</td>\n<td></td>\n<td></td>\n<td>Replace prefix</td>\n<td>test.html</td>\n</tr>\n</tbody>\n</table>\n\nAdd Rules\nEvent Notifications\n\nLast updated: 2019-09-24 17:30:12\n\nOverview\n\nIf any change is made to COS resources (such as new files uploaded or files deleted), you will receive prompt notification. Event notification can be used together with Serverless Cloud Function to meet the needs of more application scenarios:\n\n- **Interaction with other Tencent Cloud services**: For example, purge CDN cache or update the database when a new file is uploaded to COS.\n- **System integration**: Your own service APIs can be called when files in COS are created, deleted, or overwritten. In user-generated content (UGC) scenarios, with the event notification feature, the client side will be able to interact with the server side.\n- **Data processing**: Files in COS can be automatically processed, such as automatic decompression and AI recognition.\n\nCOS event notification has the following features:\n\n- Async processing: sending notifications does not affect normal COS operations.\n- Notification targets: notifications can only be sent to SCF functions in the same region.\n\nCurrently, the feature covers the following COS events:\n\n<table>\n<thead>\n<tr>\n<th>Event Type</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>cos: ObjectCreated:*</td>\n<td>All upload events mentioned below can trigger the SCF function</td>\n</tr>\n<tr>\n<td>cos: ObjectCreated:Put</td>\n<td>Creating a file via the Put Object API</td>\n</tr>\n<tr>\n<td>cos: ObjectCreated:Post</td>\n<td>Creating a file via the Post Object API</td>\n</tr>\n<tr>\n<td>cos: ObjectCreated:Copy</td>\n<td>Creating a file via the Put Object - Copy API</td>\n</tr>\n<tr>\n<td>cos: ObjectCreated:CompleteMultipartUpload</td>\n<td>Creating a file with the CompleteMultipartUpload API</td>\n</tr>\n<tr>\n<td>cos: ObjectRemove:*</td>\n<td>All deletion events mentioned below can trigger the SCF function</td>\n</tr>\n<tr>\n<td>cos: ObjectRemove:Delete</td>\n<td>Deleting an object via the Delete Object API or deleting an object with a specified version using <code>versionid</code> from a bucket for which versioning is not</td>\n</tr>\n<tr>\n<td>Event Type</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------------------------</td>\n<td>---------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>cos: ObjectRemove:DeleteMarkerCreated</td>\n<td>Deleting an object via the Delete Object API from a bucket for which versioning is enabled or suspended</td>\n</tr>\n</tbody>\n</table>\n\n## How to Use COS Event Notification\n\nPlease follow the steps below:\n\n1. **Create an SCF function**\n - You can create a function in the [SCF Console](#) or using the CLI. When creating the function, you need to select the runtime environment based on the language you will use to write the function and submit the function code either by editing online or uploading a local code package.\n - You can also use a preconfigured SCF template to simplify the creation. For more information, see [Create a Function](#). The way to write the function varies by programming language. For more information, see the [SCF documentation](#).\n\n2. **Test the function**\n - Once a function is created, you can test it with a test template which can simulate COS events and trigger the function. For more information, see [Testing a Function](#).\n\n3. **Add a trigger**\n - After you finish the testing, you can bind the SCF function with a bucket by creating a COS trigger in the console or using the command line. For more information, see [Creating a Trigger](#).\n\n4. **Check if the function works**\n - After completing the steps above, you can make changes to the bucket in COS to see if everything works. For example, you can upload or delete files in the console or using the COS Browser and then go to [SCF Console > Function Details > Execution Logs](#) to check if everything works properly.\n\nFor more information on SCF COS triggers, see [COS Trigger](#).\nData Extraction\n\nSELECT Overview\n\nLast updated: 2020-03-17 17:35:54\n\nThe COS Select feature uses structured query language (SQL) to filter objects stored in COS in order to extract a specific object and get the desired data. By filtering object data using this feature, you can reduce the amount of data transferred by COS, which helps lower the cost and delay in data extraction.\n\nThe COS Select feature currently allows you to extract objects stored in CSV and JSON formats and compressed by gzip and bzip2 (for CSV and JSON objects only). In addition, you can save the extraction result in CSV and JSON formats and specify how to separate the result records.\n\nYou can pass in an SQL expression to COS in your request. COS Select currently only supports certain SQL expressions. For more information, see SQL Functions.\n\nYou can use the COS SDK, API, COSCMD, or COS Console to execute on SQL queries. Note that certain restrictions apply on file extraction if you use the COS Console: Up to 128 MB of files can be extracted, and up to 40 MB of data can be returned. To extract more data, use other methods.\n\n- For more information on data types supported by COS Select and current reserved fields, see Data Types and Reserved Fields.\n- Currently, the extraction function only supports public cloud regions in mainland China.\n\nUse Limits\n\nThe following restrictions apply to COS Select:\n\n- You must have the cos:GetObject permission to the queried object. A root account has this permission by default.\n- Only objects in standard storage class can be extracted.\n- The maximum length of an SQL expression is 256 KB.\n- The maximum length of a single record in the extraction result is 1 MB.\n\nSQL clauses currently supported by COS Select include:\n\n- SELECT statement\n- FROM clause\n- WHERE clause\n- LIMIT clause\n\nFor more information on SQL clauses, see SELECT Command.\n\nFunctions currently supported by COS Select include:\n\n- Aggregate functions, such as AVG function, COUNT function, MAX function, MIN function, and SUM function.\n- Condition functions, such as COALESCE function and NULLIF function.\n- Conversion functions, such as CAST function.\n- Date functions, such as DATE_ADD function, DATE_DIFF function, EXTRACT function, TO_STRING function, TO_TIMESTAMP function, and UTCNOW function.\nString functions, such as CHAR_LENGTH function, CHARACTER_LENGTH function, LOWER function, SUBSTRING function, TRIM function, and UPPER function.\n\n- For more information on SQL functions, see SQL Functions.\n\nCOS Select currently supports the following operators:\n\n- Logical operators: AND, NOT, OR\n- Comparison operators: <, >, <>, =, !=, BETWEEN, IN\n- Pattern matching operators: LIKE\n- Mathematical operators: +, -, *, %\n\n- For more information on operators, see Operators.\n\nInitiating an extraction request\n\nYou can initiate an extraction request using the console, API, or SDK:\n\n- If you use the console, see Data Extraction.\n- If you use the SDK, go to SDK Overview and select the required SDK API.\n- If you use the API, see SELECT Object Content.\n\nFAQ\n\nIf a problem occurs when you execute on a query, COS Select will return an error code and associated error message. For the list of error codes and descriptions, see Special Error Codes.\nSELECT Command\n\nOverview\n\nThe COS Select feature only supports the SELECT command to extract the required data and reduce the amount of data transferred, which helps lower the costs and request delay. The following are the standard clauses supported by SELECT queries:\n\n- SELECT statement\n- WHERE clause\n- LIMIT clause\n\nCOS Select currently does not support clause queries or joins.\n\nSELECT Statement\n\nThe SELECT statement can extract the data you want to see from a COS object. You can query the data at different dimensions such as column name, function, and expression, and the query result will be returned as a list. The format of SELECT statement call is as follows:\n\n```sql\nSELECT *\nSELECT projection [ AS column_alias | column_alias ] [, ...]\n```\n\nThe first SELECT statement is marked with `*` (asterisk) and will return all the columns in the COS object. The second one uses a user-defined output scalar expression, and `projection` creates a list of outputs with custom names for each column.\n\nWHERE Clause\n\nThe WHERE clause uses the following syntax:\n\n```sql\nWHERE condition\n```\n\nThe WHERE clause filters data by `condition`. `condition` is an expression that returns a Boolean result, and only rows with a return value of TRUE will be output in the result.\n\nLIMIT Clause\n\nThe LIMIT clause uses the following syntax:\n\n```sql\nLIMIT number\n```\n\nThe LIMIT clause sets a limit on the number of records to be returned per query, which can be specified using the `number` parameter.\n\nAccess Attributes\nThe SELECT and WHERE clauses can select the fields to be queried in any of the following ways, depending on whether the file format is CSV or JSON.\n\n**CSV**\n- **Column number**: You can use \\_N\\_ to specify the data in column N for query. For any CSV files, the column number increases from 1. For example, the first column is numbered \\_1\\_ and the second column is numbered \\_2\\_. In the SELECT and WHERE clauses, it is valid to specify the column to be queried using \\_N\\_ or alias.\\_N\\_.\n- **Column header**: If the CSV file to be queried contains column headers, the SELECT and WHERE clauses can use the headers to specify the columns to be queried, which can be specified using alias.column_name or column_name in the SELECT and WHERE clauses in an SQL statement.\n\n**JSON**\n- **Document**: You can access a JSON document using alias.name. A nested array can be accessed in a way such as alias.name1.name2.name3.\n- **List**: You can access the elements in a list using an index, which is numbered from 0 and uses the \\[\\] operator. For example, you can access the second element in a JSON list using alias[1]. If you need to access a nested array, you can also do so in a way such as alias.name1.name2[1].name3.\n\n**Samples**\nThe following is the sample data in the samples:\n\n```json\n{\n \"name\": \"Leon\",\n \"org\": \"Tencent\",\n \"projects\": [\n {\n \"project_name\": \"project1\", \"completed\": true,\n },\n {\n \"project_name\": \"project2\", \"completed\": false\n }\n ]\n}\n```\n\n- **Sample 1**: The following is the SQL statement used to query name in the sample data and the query result:\n\n ```sql\n Select s.name from COSObject s\n where s.name = \"Leon\"\n ```\n\n- **Sample 2**: The following is the SQL statement used to query project_name in the sample data and the query result:\n\n ```sql\n Select s.projects[0].project_name from COSObject s\n where s.projects[0].project_name = \"project1\"\n ```\n\n**Case Sensitivity of Headers and Attribute Names**\nYou can use double quotation marks to indicate whether headers in a CSV file and attribute names in a JSON file are case-sensitive. If no double quotation marks are added, the headers/attribute names are case-insensitive. If this is not explicitly specified, COS Select may throw an exception.\n\n- **Sample 1**: Query objects with a header/attribute name containing \"NAME\".\n Because the following sample SQL query does not contain double quotation marks, the query is case-insensitive. As this header is present in the table, a value will be successfully returned eventually.\nBecause the following sample SQL query contains double quotation marks, the query is case-sensitive. As the table does not contain this header, the `SQLParsingError` 400 error will be eventually returned.\n\n```\nSELECT s.\"name\" from COSObject s\n```\n\nSample 2. Query objects with a header/attribute name containing \"NAME\" and \"name\".\nBecause the following sample SQL query does not contain double quotation marks, the query is case-insensitive. As the table contains two headers \"NAME\" and \"name\", the query command is ambiguous, and the `AmbiguousFieldName` exception will be thrown.\n\n```\nSELECT s.name from COSObject s\n```\n\nBecause the following sample SQL query contains double quotation marks, the query is case-sensitive. As the table contains the header \"NAME\", the query result will be successfully returned.\n\n```\nSELECT s.\"NAME\" from COSObject s\n```\n\nUsing Reserved Fields as User-defined Fields\n\nThe SQL expressions of COS Select have certain reserved fields such as function name, data type, and operator. Sometimes you probably use these reserved fields as column headers in a CSV file or attribute names in a JSON, which may cause conflicts with reserved fields. In this case, you can use double quotation marks to indicate that you are using a custom field; otherwise, COS will return 400 parse error.\n\nFor the complete list of reserved fields, see Reserved Words.\n\n- Sample: The header/attribute name in the object to be queried contains a reserved field \"CAST\".\n The following sample SQL query uses double quotation marks to indicate that CAST is a user-defined field, so the query result will be successfully returned.\n\n```\nSELECT s.\"CAST\" from COSObject s\n```\n\nThe following sample SQL query does not use double quotation marks to indicate that CAST is a user-defined field, so COS will treat it as a reserved field and return 400 parse error.\n\n```\nSELECT s.CAST from COSObject s\n```\n\nScalar Expressions\n\nIn the SELECT statement and the WHERE clause, you can use SQL scalar expressions (expressions that return a scalar). Currently, COS Select supports the following forms:\n\n- **literal**: SQL text.\n- **column_reference**: column_name or alias.column_name.\n- **unary_op expression**: SQL unary operator.\n- **expression binary_op expression**: SQL binary operator.\n- **func_name**: Name of the called scalar function.\n- `expression [ NOT ] BETWEEN expression AND expression`\n- `expression LIKE expression [ ESCAPE expression ]`\nAggregate Functions\n\nCOS Select supports the following aggregate functions:\n\n<table>\n<thead>\n<tr>\n<th>Function Name</th>\n<th>Parameter Type</th>\n<th>Return Type</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AVG(expression)</td>\n<td>INT, FLOAT, and DECIMAL</td>\n<td>DECIMAL will be returned if the input parameter is of integer type, and FLOAT if float type. The same type as the input parameter will be returned in all other cases.</td>\n</tr>\n<tr>\n<td>COUNT</td>\n<td>-</td>\n<td>INT</td>\n</tr>\n<tr>\n<td>MAX(expression)</td>\n<td>INT and DECIMAL</td>\n<td>The return value type is the same as that of the input parameter</td>\n</tr>\n<tr>\n<td>MIN(expression)</td>\n<td>INT and DECIMAL</td>\n<td>The return value type is the same as that of the input parameter</td>\n</tr>\n<tr>\n<td>SUM(expression)</td>\n<td>INT, FLOAT, DOUBLE, and DECIMAL</td>\n<td>INT will be returned if the input parameter is of integer type, and FLOAT if float type. The same type as the input parameter will be returned in all other cases.</td>\n</tr>\n</tbody>\n</table>\n\nCondition Functions\n\nCOS Select supports the following condition functions:\n\n**COALESCE**\n\nThe COALESCE function determines the input parameters in sequence and returns the first non-null parameter value. If the input parameters do not include a non-null parameter, the function will return a null value.\n\n**Syntax**\n\n```\nCOALESCE ( expression, expression, ... )\n```\n\nValues, arrays, or nested functions of INT, String, and Float types can be passed in for the `expression` parameter.\n\n**Samples**\n\n```\nCOALESCE(1) -- 1\nCOALESCE(1, null) -- 1\nCOALESCE(null, null, 1) -- 1\nCOALESCE(missing, 1) -- 1\nCOALESCE(null, 'string') -- 'string'\nCOALESCE(null) -- null\nCOALESCE(null, null) -- null\nCOALESCE(missing) -- null\nCOALESCE(missing, missing) -- null\n```\n\n**NULLIF**\n\nThe NULLIF function determines the difference between two parameters passed in. If the two parameters have the same value, NULL will be returned; otherwise, the value of the first parameter passed in will be returned.\nSyntax\n\n```\nNULLIF ( expression1, expression2 )\n```\n\nValues, arrays, or nested functions of INT, String, and Float types can be passed in for the `expression` parameter.\n\nSamples\n\n```\nNULLIF(1, 2) -- 1\nNULLIF(1, '1') -- 1\nNULLIF(1, NULL) -- 1\nNULLIF(1, 1) -- null\nNULLIF(1.0, 1) -- null\nNULLIF(missing, null) -- null\nNULLIF(missing, missing) -- null\nNULLIF([[1], [1]]) -- null\nNULLIF(NULL, 1) -- null\nNULLIF(null, null) -- null\n```\n\nConversion Functions\n\nCOS Select supports the following conversion functions:\n\n**CAST**\n\nThe CAST function converts one instance to another instance. The instance can be either a value or a function that can be calculated to a certain value.\n\nSyntax\n\n```\nCAST ( expression AS data_type )\n```\n\n- The `expression` parameter can be a value, an array, an operator, or an SQL function that can be calculated to a certain value.\n- The `data_type` parameter is the data type after conversion, such as INT. For the data types currently supported by COS Select, see Data Types.\n\nSamples\n\n```\nCAST('2007-04-05T14:30Z' AS TIMESTAMP)\nCAST(0.456 AS FLOAT)\n```\n\nDate Functions\n\nCOS Select supports the following date functions:\n\n**DATE_ADD**\n\nThe DATE_ADD function adds a specified time interval to a part (year, month, day, hour, minute, or second) of a specific timestamp and returns a new timestamp.\nSyntax\n\nDATE_ADD( date_part, quantity, timestamp )\n\n- The date_part parameter specifies the part of the timestamp to be modified, which can be year, month, day, hour, minute, or second.\n- The quantity parameter represents the value to be added, which must be a positive integer.\n- The timestamp parameter represents the timestamp to be modified.\n\nSamples\n\nDATE_ADD(year, 5, `2010-01-01T`) -- 2015-01-01\nDATE_ADD(month, 1, `2010T`) -- 2010-02T\nDATE_ADD(month, 13, `2010T`) -- 2011-02T\nDATE_ADD(day, -1, `2017-01-01T`) -- 2017-01-00\nDATE_ADD(hour, 1, `2017T`) -- 2017-01-01T01:00:00\nDATE_ADD(hour, 1, `2017-01-02T03:04Z`) -- 2017-01-02T04:04Z\nDATE_ADD(minute, 1, `2017-01-02T03:04:05.006Z`) -- 2017-01-02T03:05:05.006Z\nDATE_ADD(second, 1, `2017-01-02T03:04:05.006Z`) -- 2017-01-02T03:04:06.006Z\n\nDATE_DIFF\n\nThe DATE_DIFF function compares two valid timestamps and returns the difference between them, which can be displayed in the specified unit of time. If the date_part value of timestamp1 is greater than that of timestamp2, a positive number will be returned; otherwise, a negative number will be returned.\n\nSyntax\n\nDATE_DIFF( date_part, timestamp1, timestamp2 )\n\n- The date_part parameter specifies the unit of time which the two timestamps are compared in and can be year, month, day, hour, minute, or second.\n- The timestamp1 parameter is the first input timestamp.\n- The timestamp2 parameter is the second input timestamp.\n\nSamples\n\nDATE_DIFF(year, `2010-01-01T`, `2011-01-01T`) -- 1\nDATE_DIFF(year, `2010T`, `2010-05T`) -- 4\nDATE_DIFF(month, `2010T`, `2011T`) -- 12\nDATE_DIFF(month, `2011T`, `2010T`) -- -12\nDATE_DIFF(day, `2010-01-01T23:00T`, `2010-01-02T01:00T`) -- 0\n\nEXTRACT\n\nThe EXTRACT function extracts a value in the specified unit of time from a given timestamp.\n\nSyntax\n\nEXTRACT( date_part FROM timestamp )\nThe parameter `date_part` specifies the unit of time to be extracted, which can be year, month, day, hour, minute, or second. The `timestamp` parameter represents the input timestamp.\n\n**Samples**\n\n```\nEXTRACT(YEAR FROM '2010-01-01T') -- 2010\nEXTRACT(MONTH FROM '2010T') -- 1\nEXTRACT(MONTH FROM '2010-10T') -- 10\nEXTRACT(HOUR FROM '2017-01-02T03:04:05+07:08') -- 3\nEXTRACT(MINUTE FROM '2017-01-02T03:04:05+07:08') -- 4\nEXTRACT(TIMEZONE_HOUR FROM '2017-01-02T03:04:05+07:08') -- 7\nEXTRACT(TIMEZONE_MINUTE FROM '2017-01-02T03:04:05+07:08') -- 8\n```\n\n**TO_STRING**\n\nThe `TO_STRING` function converts a timestamp to a string of time in the specified format.\n\n**Syntax**\n\n```\nTO_STRING ( timestamp time_format_pattern )\n```\n\n- The `timestamp` parameter specifies the timestamp to be converted.\n- The `time_format_pattern` parameter specifies the time format.\n\n**Format**\n\n<table>\n<thead>\n<tr>\n<th>Format</th>\n<th>Description</th>\n<th>Sample</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>yy</td>\n<td>2-digit year</td>\n<td>98</td>\n</tr>\n<tr>\n<td>y</td>\n<td>4-digit year</td>\n<td>1998</td>\n</tr>\n<tr>\n<td>yyyy</td>\n<td>Year expressed by 4 digits. If there are less than 4 digits, 0 will be automatically added</td>\n<td>0199</td>\n</tr>\n<tr>\n<td>M</td>\n<td>Month</td>\n<td>1</td>\n</tr>\n<tr>\n<td>MM</td>\n<td>Month expressed by 2 digits. If there are less than 2 digits, 0 will be automatically added</td>\n<td>01</td>\n</tr>\n<tr>\n<td>MMM</td>\n<td>English abbreviation of a month</td>\n<td>Jan</td>\n</tr>\n<tr>\n<td>MMMM</td>\n<td>Full English name of a month</td>\n<td>January</td>\n</tr>\n<tr>\n<td>MMMMM</td>\n<td>Initial of a month</td>\n<td>J (not applicable to the <code>to_timestamp</code> function)</td>\n</tr>\n<tr>\n<td>d</td>\n<td>Day (1-31) in a month</td>\n<td>1</td>\n</tr>\n<tr>\n<td>dd</td>\n<td>Day expressed by 2 digits (1-31)</td>\n<td>01</td>\n</tr>\n<tr>\n<td>a</td>\n<td>Symbol for morning or afternoon (AM/PM)</td>\n<td>AM</td>\n</tr>\n<tr>\n<td>h</td>\n<td>Hour in 12-hour time</td>\n<td>1</td>\n</tr>\n<tr>\n<td>hh</td>\n<td>Hour expressed by 2 digits in 12-hour time</td>\n<td>01</td>\n</tr>\n<tr>\n<td>H</td>\n<td>Hour in 24-hour time</td>\n<td>1</td>\n</tr>\n<tr>\n<td>Format</td>\n<td>Description</td>\n<td>Sample</td>\n</tr>\n<tr>\n<td>--------</td>\n<td>-------------</td>\n<td>--------</td>\n</tr>\n<tr>\n<td>HH</td>\n<td>Hour expressed by 2 digits in 24-hour time</td>\n<td>01</td>\n</tr>\n<tr>\n<td>m</td>\n<td>Minute (00-59)</td>\n<td>1</td>\n</tr>\n<tr>\n<td>mm</td>\n<td>Minute expressed by 2 digits in 24-hour time</td>\n<td>01</td>\n</tr>\n<tr>\n<td>s</td>\n<td>Second (00-59)</td>\n<td>1</td>\n</tr>\n<tr>\n<td>ss</td>\n<td>Second expressed by 2 digits in 24-hour time</td>\n<td>01</td>\n</tr>\n<tr>\n<td>S</td>\n<td>Decimal part of the second (accuracy: 0.1; value range: 0.0 - 0.9)</td>\n<td>0</td>\n</tr>\n<tr>\n<td>SS</td>\n<td>Decimal part of the second (accuracy: 0.01; value range: 0.00 - 0.99)</td>\n<td>6</td>\n</tr>\n<tr>\n<td>SSS</td>\n<td>Decimal part of the second (accuracy: 0.001; value range: 0.000 - 0.999)</td>\n<td>60</td>\n</tr>\n<tr>\n<td>...</td>\n<td>...</td>\n<td>...</td>\n</tr>\n<tr>\n<td>SSSSSSSS</td>\n<td>Decimal part of the second (accuracy: 0.000000001; value range: 0.000000000 - 0.999999999)</td>\n<td>60000000</td>\n</tr>\n<tr>\n<td>n</td>\n<td>Nanosecond</td>\n<td>60000000</td>\n</tr>\n<tr>\n<td>X</td>\n<td>Hour-level offset. If the offset is 0, then this will be "Z"</td>\n<td>+01 or Z</td>\n</tr>\n<tr>\n<td>XX or XXXX</td>\n<td>Hour- or minute-level offset. If the offset is 0, then this will be "Z"</td>\n<td>+0100 or Z</td>\n</tr>\n<tr>\n<td>xxx or xxxxx</td>\n<td>Hour- or minute-level offset. If the offset is 0, then this will be "Z"</td>\n<td>+01:00 or Z</td>\n</tr>\n<tr>\n<td>x</td>\n<td>Hour-level offset</td>\n<td>1</td>\n</tr>\n<tr>\n<td>xx or xxxx</td>\n<td>Hour- or minute-level offset</td>\n<td>0100</td>\n</tr>\n<tr>\n<td>xxx or xxxxx</td>\n<td>Hour- or minute-level offset</td>\n<td>01:00</td>\n</tr>\n</tbody>\n</table>\n\n**Samples**\n\nTO_STRING('1998-07-20T20:18Z', 'MMMM d, y') -- \"July 20, 1998\"\nTO_STRING('1998-07-20T20:18Z', 'MMM d, yyyy') -- \"Jul 20, 1998\"\nTO_STRING('1998-07-20T20:18Z', 'M-d-yy') -- \"7-20-69\"\nTO_STRING('1998-07-20T20:18Z', 'MM d, y:m a') -- \"July 20, 1998 8:18 PM\"\nTO_STRING('1998-07-20T20:18Z', 'y-MM-dd' 'T' 'H:mm:ssX') -- \"1998-07-20T20:18:00Z\"\nTO_STRING('1998-07-20T20:18+08:00Z', 'y-MM-dd' 'T' 'H:mm:ssX') -- \"1998-07-20T20:18:00+0800\"\nTO_STRING('1998-07-20T20:18+08:00', 'y-MM-dd' 'T' 'H:mm:ssXXX') -- \"1998-07-20T20:18:00+08:00\"\n\n**TO_TIMESTAMP**\n\nThe TO_TIMESTAMP function converts a string of time to a timestamp.\n\n**Syntax**\n\nTO_TIMESTAMP ( string )\n\nThe string parameter represents the input time string.\nSamples\n\n```sql\nTO_TIMESTAMP('2007T') -- '2007T'\nTO_TIMESTAMP('2007-02-23T12:14:33.079-08:00') -- '2007-02-23T12:14:33.079-08:00'\n```\n\n### UTCNOW\n\nThe UTCNOW function returns the current timestamp in UTC.\n\n**Syntax**\n\n```sql\nUTCNOW()\n```\n\n**Samples**\n\n```sql\n```\n\n### String Functions\n\nCOS Select supports the following string functions:\n\n**CHAR_LENGTH, CHARACTER_LENGTH**\n\nBoth CHAR_LENGTH and CHARACTER_LENGTH can compute the number of characters in a string, and they have the same semantics.\n\n**Syntax**\n\n```sql\nCHAR_LENGTH ( string )\n```\n\nThe `string` parameter specifies the string for character counting.\n\n**Samples**\n\n```sql\nCHAR_LENGTH('null') -- 4\nCHAR_LENGTH('tencent') -- 7\n```\n\n**LOWER**\n\nThe LOWER function converts all uppercase letters in the specified string to lowercase letters, with all non-uppercase letters left unchanged.\n\n**Syntax**\n\n```sql\nLOWER ( string )\n```\n\nThe `string` parameter specifies the string for which to convert uppercase letters to lowercase letters.\n\n**Samples**\nLOWER('TENcent') -- 'tencent'\n\n**SUBSTRING**\n\nThe SUBSTRING function returns a substring of a string. You can specify an index from which the SUBSTRING function will extract the remainder of the original string based on the length of the specified substring and return the result.\n\nIf the input string contains only 1 character, and the index is set to greater than 1, the SUBSTRING function will automatically switch it to 1.\n\n**Syntax**\n\n```sql\nSUBSTRING( string FROM start [ FOR length ] )\n```\n\n- The `string` parameter specifies the string from which to extract a substring.\n- The `start` parameter represents an index value of the string as the starting position for extraction.\n- The `length` parameter specifies the length of the substring. If the length of the substring is not specified, the remainder of the string will be extracted.\n\n**Samples**\n\n```\nSUBSTRING(\"123456789\", 0) -- \"123456789\"\nSUBSTRING(\"123456789\", 1) -- \"123456789\"\nSUBSTRING(\"123456789\", 2) -- \"23456789\"\nSUBSTRING(\"123456789\", -4) -- \"123456789\"\nSUBSTRING(\"123456789\", 0, 999) -- \"123456789\"\nSUBSTRING(\"123456789\", 1, 5) -- \"12345\"\n```\n\n**TRIM**\n\nThe TRIM function deletes all characters before the first character or after the last character of the specified string. \" \" is the default character to be deleted.\n\n**Syntax**\n\n```sql\nTRIM ( [LEADING | TRAILING | BOTH remove_chars] FROM string )\n```\n\n- The `string` parameter specifies the string to be manipulated.\n- The `LEADING | TRAILING | BOTH` parameter specifies the extra characters to be deleted, which can be before the string (LEADING), after the string (TRAILING), or both (BOTH).\n- The `remove_chars` parameter specifies the type of extra characters to be deleted. It can be a string containing more than one characters. The TRIM function will delete all extra characters of the corresponding type that are identified by the TRIM function before or after the `string` parameter.\n\n**Samples**\n\n```\nTRIM(' foobar ') -- 'foobar'\nTRIM(' \\#foobar\\#' ) -- '\\#foobar\\#' \nTRIM.LEADING FROM ' foobar ' ) -- 'foobar'\n```\nTRIM(TRAILING FROM 'foobar') -- 'foobar'\nTRIM(BOTH FROM 'foobar') -- 'foobar'\nTRIM(BOTH '12' FROM '1112211foobar22211122') -- 'foobar'\n\n**UPPER**\n\nThe UPPER function converts all lowercase letters to uppercase letters with non-lowercase letters left unchanged.\n\n**Syntax**\n\n```sql\nUPPER ( string )\n```\n\nThe `string` parameter specifies the string to be converted to uppercase letters.\n\n**Samples**\n\n```sql\nUPPER('tenCENT') -- 'TENCENT'\n```\nReserved Words\n\nIn order to ensure normal operation and subsequent expansion, the COS Select feature has the following reserved fields such as function name, data type, and operator. You may use these fields to facilitate your SQL queries.\n\n<table>\n<thead>\n<tr>\n<th>No.</th>\n<th>Field</th>\n<th>No.</th>\n<th>Field</th>\n<th>No.</th>\n<th>Field</th>\n<th>No.</th>\n<th>Field</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>absolute</td>\n<td>51</td>\n<td>create</td>\n<td>101</td>\n<td>goto</td>\n<td>151</td>\n<td>octet_length</td>\n</tr>\n<tr>\n<td>2</td>\n<td>action</td>\n<td>52</td>\n<td>cross</td>\n<td>102</td>\n<td>grant</td>\n<td>152</td>\n<td>of</td>\n</tr>\n<tr>\n<td>3</td>\n<td>add</td>\n<td>53</td>\n<td>current</td>\n<td>103</td>\n<td>group</td>\n<td>153</td>\n<td>on</td>\n</tr>\n<tr>\n<td>4</td>\n<td>all</td>\n<td>54</td>\n<td>current_date</td>\n<td>104</td>\n<td>having</td>\n<td>154</td>\n<td>only</td>\n</tr>\n<tr>\n<td>5</td>\n<td>allocate</td>\n<td>55</td>\n<td>current_time</td>\n<td>105</td>\n<td>hour</td>\n<td>155</td>\n<td>open</td>\n</tr>\n<tr>\n<td>6</td>\n<td>alter</td>\n<td>56</td>\n<td>current_timestamp</td>\n<td>106</td>\n<td>identity</td>\n<td>156</td>\n<td>option</td>\n</tr>\n<tr>\n<td>7</td>\n<td>and</td>\n<td>57</td>\n<td>current_user</td>\n<td>107</td>\n<td>immediate</td>\n<td>157</td>\n<td>or</td>\n</tr>\n<tr>\n<td>8</td>\n<td>any</td>\n<td>58</td>\n<td>cursor</td>\n<td>108</td>\n<td>in</td>\n<td>158</td>\n<td>order</td>\n</tr>\n<tr>\n<td>9</td>\n<td>are</td>\n<td>59</td>\n<td>date</td>\n<td>109</td>\n<td>indicator</td>\n<td>159</td>\n<td>outer</td>\n</tr>\n<tr>\n<td>10</td>\n<td>as</td>\n<td>60</td>\n<td>day</td>\n<td>110</td>\n<td>initially</td>\n<td>160</td>\n<td>output</td>\n</tr>\n<tr>\n<td>11</td>\n<td>asc</td>\n<td>61</td>\n<td>deallocate</td>\n<td>111</td>\n<td>inner</td>\n<td>161</td>\n<td>overlaps</td>\n</tr>\n<tr>\n<td>12</td>\n<td>assertion</td>\n<td>62</td>\n<td>dec</td>\n<td>112</td>\n<td>input</td>\n<td>162</td>\n<td>pad</td>\n</tr>\n<tr>\n<td>13</td>\n<td>at</td>\n<td>63</td>\n<td>decimal</td>\n<td>113</td>\n<td>insensitive</td>\n<td>163</td>\n<td>partial</td>\n</tr>\n<tr>\n<td>14</td>\n<td>authorization</td>\n<td>64</td>\n<td>declare</td>\n<td>114</td>\n<td>insert</td>\n<td>164</td>\n<td>pivot</td>\n</tr>\n<tr>\n<td>15</td>\n<td>avg</td>\n<td>65</td>\n<td>default</td>\n<td>115</td>\n<td>int</td>\n<td>165</td>\n<td>position</td>\n</tr>\n<tr>\n<td>16</td>\n<td>bag</td>\n<td>66</td>\n<td>deferrable</td>\n<td>116</td>\n<td>integer</td>\n<td>166</td>\n<td>precision</td>\n</tr>\n<tr>\n<td>17</td>\n<td>begin</td>\n<td>67</td>\n<td>deferred</td>\n<td>117</td>\n<td>intersect</td>\n<td>167</td>\n<td>prepare</td>\n</tr>\n<tr>\n<td>18</td>\n<td>between</td>\n<td>68</td>\n<td>delete</td>\n<td>118</td>\n<td>interval</td>\n<td>168</td>\n<td>preserve</td>\n</tr>\n<tr>\n<td>19</td>\n<td>bit</td>\n<td>69</td>\n<td>desc</td>\n<td>119</td>\n<td>into</td>\n<td>169</td>\n<td>primary</td>\n</tr>\n<tr>\n<td>20</td>\n<td>bit_length</td>\n<td>70</td>\n<td>describe</td>\n<td>120</td>\n<td>is</td>\n<td>170</td>\n<td>prior</td>\n</tr>\n<tr>\n<td>21</td>\n<td>blob</td>\n<td>71</td>\n<td>descriptor</td>\n<td>121</td>\n<td>isolation</td>\n<td>171</td>\n<td>privileges</td>\n</tr>\n<tr>\n<td>22</td>\n<td>bool</td>\n<td>72</td>\n<td>diagnostics</td>\n<td>122</td>\n<td>join</td>\n<td>172</td>\n<td>procedure</td>\n</tr>\n<tr>\n<td>23</td>\n<td>boolean</td>\n<td>73</td>\n<td>disconnect</td>\n<td>123</td>\n<td>key</td>\n<td>173</td>\n<td>public</td>\n</tr>\n<tr>\n<td>24</td>\n<td>both</td>\n<td>74</td>\n<td>distinct</td>\n<td>124</td>\n<td>language</td>\n<td>174</td>\n<td>read</td>\n</tr>\n<tr>\n<td>25</td>\n<td>by</td>\n<td>75</td>\n<td>domain</td>\n<td>125</td>\n<td>last</td>\n<td>175</td>\n<td>real</td>\n</tr>\n<tr>\n<td>26</td>\n<td>cascade</td>\n<td>76</td>\n<td>double</td>\n<td>126</td>\n<td>leading</td>\n<td>176</td>\n<td>references</td>\n</tr>\n<tr>\n<td>27</td>\n<td>cascaded</td>\n<td>77</td>\n<td>drop</td>\n<td>127</td>\n<td>left</td>\n<td>177</td>\n<td>relative</td>\n</tr>\n<tr>\n<td>28</td>\n<td>case</td>\n<td>78</td>\n<td>else</td>\n<td>128</td>\n<td>level</td>\n<td>178</td>\n<td>restrict</td>\n</tr>\n<tr>\n<td>No.</td>\n<td>Field</td>\n<td>No.</td>\n<td>Field</td>\n<td>No.</td>\n<td>Field</td>\n<td>No.</td>\n<td>Field</td>\n</tr>\n<tr>\n<td>-----</td>\n<td>---------------</td>\n<td>-----</td>\n<td>---------------</td>\n<td>-----</td>\n<td>---------------</td>\n<td>-----</td>\n<td>---------------</td>\n</tr>\n<tr>\n<td>29</td>\n<td>cast</td>\n<td>79</td>\n<td>end</td>\n<td>129</td>\n<td>like</td>\n<td>179</td>\n<td>revoke</td>\n</tr>\n<tr>\n<td>30</td>\n<td>catalog</td>\n<td>80</td>\n<td>end-exec</td>\n<td>130</td>\n<td>limit</td>\n<td>180</td>\n<td>right</td>\n</tr>\n<tr>\n<td>31</td>\n<td>char</td>\n<td>81</td>\n<td>escape</td>\n<td>131</td>\n<td>list</td>\n<td>181</td>\n<td>rollback</td>\n</tr>\n<tr>\n<td>32</td>\n<td>char_length</td>\n<td>82</td>\n<td>except</td>\n<td>132</td>\n<td>local</td>\n<td>182</td>\n<td>rows</td>\n</tr>\n<tr>\n<td>33</td>\n<td>character</td>\n<td>83</td>\n<td>exception</td>\n<td>133</td>\n<td>lower</td>\n<td>183</td>\n<td>schema</td>\n</tr>\n<tr>\n<td>34</td>\n<td>character_length</td>\n<td>84</td>\n<td>exec</td>\n<td>134</td>\n<td>match</td>\n<td>184</td>\n<td>scroll</td>\n</tr>\n<tr>\n<td>35</td>\n<td>check</td>\n<td>85</td>\n<td>execute</td>\n<td>135</td>\n<td>max</td>\n<td>185</td>\n<td>second</td>\n</tr>\n<tr>\n<td>36</td>\n<td>clob</td>\n<td>86</td>\n<td>exists</td>\n<td>136</td>\n<td>min</td>\n<td>186</td>\n<td>section</td>\n</tr>\n<tr>\n<td>37</td>\n<td>close</td>\n<td>87</td>\n<td>external</td>\n<td>137</td>\n<td>minute</td>\n<td>187</td>\n<td>select</td>\n</tr>\n<tr>\n<td>38</td>\n<td>coalesce</td>\n<td>88</td>\n<td>extract</td>\n<td>138</td>\n<td>missing</td>\n<td>188</td>\n<td>session</td>\n</tr>\n<tr>\n<td>39</td>\n<td>collate</td>\n<td>89</td>\n<td>false</td>\n<td>139</td>\n<td>module</td>\n<td>189</td>\n<td>session_user</td>\n</tr>\n<tr>\n<td>40</td>\n<td>collation</td>\n<td>90</td>\n<td>fetch</td>\n<td>140</td>\n<td>month</td>\n<td>190</td>\n<td>set</td>\n</tr>\n<tr>\n<td>41</td>\n<td>column</td>\n<td>91</td>\n<td>first</td>\n<td>141</td>\n<td>names</td>\n<td>191</td>\n<td>sexp</td>\n</tr>\n<tr>\n<td>42</td>\n<td>commit</td>\n<td>92</td>\n<td>float</td>\n<td>142</td>\n<td>national</td>\n<td>192</td>\n<td>size</td>\n</tr>\n<tr>\n<td>43</td>\n<td>connect</td>\n<td>93</td>\n<td>for</td>\n<td>143</td>\n<td>natural</td>\n<td>193</td>\n<td>smallint</td>\n</tr>\n<tr>\n<td>44</td>\n<td>connection</td>\n<td>94</td>\n<td>foreign</td>\n<td>144</td>\n<td>nchar</td>\n<td>194</td>\n<td>some</td>\n</tr>\n<tr>\n<td>45</td>\n<td>constraint</td>\n<td>95</td>\n<td>found</td>\n<td>145</td>\n<td>next</td>\n<td>195</td>\n<td>space</td>\n</tr>\n<tr>\n<td>46</td>\n<td>constraints</td>\n<td>96</td>\n<td>from</td>\n<td>146</td>\n<td>no</td>\n<td>196</td>\n<td>sql</td>\n</tr>\n<tr>\n<td>47</td>\n<td>continue</td>\n<td>97</td>\n<td>full</td>\n<td>147</td>\n<td>not</td>\n<td>197</td>\n<td>sqrcode</td>\n</tr>\n<tr>\n<td>48</td>\n<td>convert</td>\n<td>98</td>\n<td>get</td>\n<td>148</td>\n<td>null</td>\n<td>198</td>\n<td>sqlerror</td>\n</tr>\n<tr>\n<td>49</td>\n<td>corresponding</td>\n<td>99</td>\n<td>global</td>\n<td>149</td>\n<td>nullif</td>\n<td>199</td>\n<td>sqlstate</td>\n</tr>\n<tr>\n<td>50</td>\n<td>count</td>\n<td>100</td>\n<td>go</td>\n<td>150</td>\n<td>numeric</td>\n<td>200</td>\n<td>string</td>\n</tr>\n</tbody>\n</table>\nData Types\n\nOverview\n\nCOS Select supports a wide variety of primitive data types.\n\nThe data type directly supported by a compiler is called a primitive data type.\n\nData Type Conversion\n\nCOS Select uses the CAST function to determine the data type of your input data. In general, if you do not specify a data type through the CAST function, COS Select will treat the input data as string type.\n\nFor more information on the CAST function, see the CAST section in the SQL function documentation.\n\nSupported Data Types\n\nCOS Select supports the following primitive data types:\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Description</th>\n<th>Example</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>bool</td>\n<td>TRUE/FALSE</td>\n<td>FALSE</td>\n</tr>\n<tr>\n<td>string</td>\n<td>A UTF-8-encoded string with a character length in the range of 1 - 2,147,483,647</td>\n<td>'xyz'</td>\n</tr>\n<tr>\n<td>float</td>\n<td>An 8-byte floating point</td>\n<td>CAST(0.456 AS FLOAT)</td>\n</tr>\n<tr>\n<td>decimal, numeric</td>\n<td>A decimal value with a maximum precision of 38 decimal places and in the range of $-2^{31}$ - $2^{31}-1$</td>\n<td>123.456</td>\n</tr>\n<tr>\n<td>timestamp</td>\n<td>A timestamp represents a certain moment and can be expressed with any precision. A timestamp in text format follows the W3C specification but needs to end with "T" (unless recorded in days). When a fractional second is used, it should be accurate to at least one decimal place (with no upper limit on the number of decimal places). The offset of local time can be expressed by the offset expressed by hours and minutes when compared to UTC, or "Z" can be used to express the offset of local time from UTC. The time offset does not need to be displayed when only the date is recorded.</td>\n<td>CAST('2007-04-05T14:30Z' AS TIMESTAMP)</td>\n</tr>\n</tbody>\n</table>\nOperators\nLast updated: 2019-10-25 16:04:52\n\nCOS Select supports the following operators:\n\n<table>\n<thead>\n<tr>\n<th>Operator Type</th>\n<th>Operator</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Logical operator</td>\n<td>AND, NOT, OR</td>\n</tr>\n<tr>\n<td>Comparison operator</td>\n<td><, >, <=, >=, =, <>, !>=, BETWEEN, IN, such as IN ('a', 'b', 'c')</td>\n</tr>\n<tr>\n<td>Pattern matching operator</td>\n<td>LIKE</td>\n</tr>\n<tr>\n<td>Mathematical operator</td>\n<td>+, -, *, %</td>\n</tr>\n</tbody>\n</table>\n\nPriority of Operators\n\nThe following table shows the priority of operators in descending order:\n\n<table>\n<thead>\n<tr>\n<th>Operator/Element</th>\n<th>Association</th>\n<th>Use Case</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>-</td>\n<td>Right</td>\n<td>Unary subtraction</td>\n</tr>\n<tr>\n<td>*, /, %</td>\n<td>Left</td>\n<td>Multiplication, division, and modulo</td>\n</tr>\n<tr>\n<td>+, -</td>\n<td>Left</td>\n<td>Addition and subtraction</td>\n</tr>\n<tr>\n<td>IN</td>\n<td>-</td>\n<td>Setting membership</td>\n</tr>\n<tr>\n<td>BETWEEN</td>\n<td>-</td>\n<td>In the range of ()</td>\n</tr>\n<tr>\n<td>LIKE</td>\n<td>-</td>\n<td>String pattern matching</td>\n</tr>\n<tr>\n<td><></td>\n<td>-</td>\n<td>Less than and greater than</td>\n</tr>\n<tr>\n<td>=</td>\n<td>Right</td>\n<td>Equivalence and assignment</td>\n</tr>\n<tr>\n<td>NOT</td>\n<td>Right</td>\n<td>Logical NOT</td>\n</tr>\n<tr>\n<td>AND</td>\n<td>Left</td>\n<td>Logical AND</td>\n</tr>\n<tr>\n<td>OR</td>\n<td>Left</td>\n<td>Logical OR</td>\n</tr>\n</tbody>\n</table>\nLog Management\n\nLog Management Overview\n\nOverview\n\nThe log management records the detailed access information of the specified source bucket and store the information as log files in the specified bucket to facilitate bucket management.\n\nIn the destination bucket, the log path is:\n\n```\n(Destination bucket)/(Path prefix) {YYYY}/(MM)/{DD}/(time)_{random}_{index}.gz\n```\n\nThe log is generated every 5 minutes, one record is a row, each record contains multiple fields, and the fields are separated by spaces. It should be noted that a single log file can be up to 256MB. If you generate more than 256MB of logs in these 5 minutes, your log will be split into multiple log files. The currently supported log fields are as follows:\n\n<table>\n<thead>\n<tr>\n<th>Field Number</th>\n<th>Name</th>\n<th>Meaning</th>\n<th>Example</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>eventVersion</td>\n<td>Log version</td>\n<td>1.0</td>\n</tr>\n<tr>\n<td>2</td>\n<td>bucketName</td>\n<td>Bucket name</td>\n<td>examplebucket-1250000000</td>\n</tr>\n<tr>\n<td>3</td>\n<td>qcsRegion</td>\n<td>Request region</td>\n<td>ap-beijing</td>\n</tr>\n<tr>\n<td>4</td>\n<td>eventTime</td>\n<td>Event time (request end time, which is a timestamp in UTC+0 time zone)</td>\n<td>2018-12-01T11:02:33Z</td>\n</tr>\n<tr>\n<td>5</td>\n<td>eventSource</td>\n<td>Domain name is accessed by the user</td>\n<td>examplebucket-1250000000.cos.ap-guangzhou.myqcloud.com</td>\n</tr>\n<tr>\n<td>6</td>\n<td>eventName</td>\n<td>Event name</td>\n<td>UploadPart</td>\n</tr>\n<tr>\n<td>7</td>\n<td>remoteIp</td>\n<td>Source IP</td>\n<td>192.168.0.1</td>\n</tr>\n<tr>\n<td>8</td>\n<td>userSecretKeyId</td>\n<td>User access KeyId</td>\n<td>AKIDNYVCdoQyGJ5brTf</td>\n</tr>\n<tr>\n<td>9</td>\n<td>reservedFiled</td>\n<td>reserved fields</td>\n<td>reserved fields, shown as -</td>\n</tr>\n<tr>\n<td>10</td>\n<td>reqBytesSent</td>\n<td>Request bytes</td>\n<td>83886080</td>\n</tr>\n<tr>\n<td>11</td>\n<td>deltaDataSize</td>\n<td>Change in storage made by the request (in bytes)</td>\n<td>808</td>\n</tr>\n<tr>\n<td>12</td>\n<td>reqPath</td>\n<td>Requested file path</td>\n<td>/folder/text.txt</td>\n</tr>\n<tr>\n<td>13</td>\n<td>reqMethod</td>\n<td>Request method</td>\n<td>put</td>\n</tr>\n<tr>\n<td>14</td>\n<td>userAgent</td>\n<td>User UA</td>\n<td>cos-go-sdk-v5.2.9</td>\n</tr>\n<tr>\n<td>15</td>\n<td>resHttpCode</td>\n<td>HTTP return code</td>\n<td>404</td>\n</tr>\n<tr>\n<td>16</td>\n<td>resErrorCode</td>\n<td>Error code</td>\n<td>NoSuchKey</td>\n</tr>\n<tr>\n<td>17</td>\n<td>resErrorMsg</td>\n<td>Error message</td>\n<td>The specified key does not exist.</td>\n</tr>\n<tr>\n<td>18</td>\n<td>resBytesSent</td>\n<td>Bytes returned</td>\n<td>197</td>\n</tr>\n<tr>\n<td>Field Number</td>\n<td>Name</td>\n<td>Meaning</td>\n<td>Example</td>\n</tr>\n<tr>\n<td>--------------</td>\n<td>-----------------</td>\n<td>-------------------------------------------------------------------------</td>\n<td>--------------------------</td>\n</tr>\n<tr>\n<td>19</td>\n<td>resTotalTime</td>\n<td>Total time used by the request (in milliseconds, i.e., the time between the last byte of the response and the first byte of the request)</td>\n<td>4295</td>\n</tr>\n<tr>\n<td>20</td>\n<td>logSourceType</td>\n<td>Log source type USER (User access request), CDN (CDN Origin-pull request)</td>\n<td></td>\n</tr>\n<tr>\n<td>21</td>\n<td>storageClass</td>\n<td>Storage class STANDARD, STANDARD_IA, ARCHIVE</td>\n<td></td>\n</tr>\n<tr>\n<td>22</td>\n<td>accountId</td>\n<td>Bucket owner ID 100000000001</td>\n<td></td>\n</tr>\n<tr>\n<td>23</td>\n<td>resTurnAroundTime</td>\n<td>Time used by the request server (in milliseconds, i.e., the time between the first byte of the response and the last byte of the request)</td>\n<td>4295</td>\n</tr>\n<tr>\n<td>24</td>\n<td>requester</td>\n<td>Visitor</td>\n<td>Primary account id: sub-account id, if it is anonymous access, shown as - .</td>\n</tr>\n<tr>\n<td>25</td>\n<td>requestId</td>\n<td>Request ID NWQ1ZjY4MTBfMjZiMjU4NjRfOWI1N180NDBiYTY=</td>\n<td></td>\n</tr>\n<tr>\n<td>26</td>\n<td>objectSize</td>\n<td>Object size in bytes 808, if you use Multipart Upload, the objectSize field will only be displayed when the upload is completed. This field displays - during each Multipart Upload.</td>\n<td></td>\n</tr>\n<tr>\n<td>27</td>\n<td>versionId</td>\n<td>Object version ID Random string</td>\n<td></td>\n</tr>\n<tr>\n<td>29</td>\n<td>targetStorageClass</td>\n<td>Destination storage class, recorded for replication requests STANDARD, STANDARD_IA, ARCHIVE</td>\n<td></td>\n</tr>\n<tr>\n<td>30</td>\n<td>referer</td>\n<td>Origin server address *.example.com or 111.111.111.1</td>\n<td></td>\n</tr>\n<tr>\n<td>31</td>\n<td>requestUri</td>\n<td>Request URI "GET /fdgfdfs%20/%E6%B5%AE%E7%82%B9%E6%95%B0 HTTP/1.1"</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n- The log management feature is currently only available in four regions including Beijing, Shanghai, Guangzhou, Chengdu and Toronto.\n- The log management feature requires the source bucket and destination bucket to be in the same region.\n- The destination bucket for storing the logs can be the source bucket itself, but this is not recommended.\n- Currently, logs will be generated only when the bucket is accessed through XML APIs and XML API-based SDKs or tools, not via JSON APIs or JSON API-based SDKs or tools.\n- Depending on customer needs and business development, COS may add new fields to the access logs. Please be sure to prepare for this when parsing the logs.\n\n**Enabling Log Management**\n\n**Using the Console**\n\nYou can quickly enable the log management feature in the console. For instructions, see the Console Guide - Setting Log Management.\n\n**Using the API**\nTo enable the log management feature for the specified bucket using API, follow the steps below:\n\n1. Create a log role.\n2. Grant the log role permissions.\n3. Enable log management.\n\n1. **Create a log role**\n\nCreate a log role. For more information, see [CreateRole](#). Here, `roleName` must be `CLS_QcsRole`. `policyDocument` must be:\n\n```\n{\n \"version\": \"2.0\",\n \"statement\": [{\n \"action\": \"name/sts:AssumeRole\",\n \"effect\": \"allow\",\n \"principal\": {\n \"service\": \"cls.cloud.tencent.com\"\n }\n }]\n}\n```\n\n2. **Grant the log role permissions**\n\nGrant the log role permissions. For specific API information, see [AttachRolePolicy](#). Here, the `policyName` is `QcloudCOSAccessForCLSRole`; the `roleName` is `CLS_QcsRole` as in step 1, or, the `roleID` returned upon the creation of `roleName`, for this regard.\n\n3. **Enable log management**\n\nCall the API to enable the log management feature. For specific API information, see [PUT Bucket logging](#), where the destination bucket storing the logs is required to be in the same region as the source bucket.\nRestrictions on Log Management\n\nThe log management feature is used to record the detailed access information of the specified source bucket and store the information in the specified bucket in the form of log files to facilitate bucket management.\n\nCurrently, the use limits of the log management feature are as follows:\n\n- Delivery frequency limit: A log is generated every 5 minutes.\n- Limit on the size of log file to be delivered: The log file to be delivered each time can be up to 256 MB. After this limit is exceeded, a new file will be delivered.\n- Format of the log to be delivered: Each record is saved as one line and can contain multiple fields separated by space.\n- Restrictions on the fields to be delivered: For more information on the fields to be delivered, see Log Management Overview.\n- Invalid fields: If a field in a log contains the `-` character, the field is an invalid record or the default record.\n\nContent Recorded in a Log\n\n- The requests initiated by you to upload, download, or delete an object, to create or delete a bucket, or to modify the bucket configuration.\n- The requests generated by content delivery through CDN and data pull from the COS origin server.\n\nContent Not Recorded in a Log\n\n- Offline origin-pull requests: After origin-pull is configured, if there are no objects in COS, the data will be downloaded from the origin server specified by you. This download operation is an offline origin-pull request and will not be recorded in the log.\n- Redirects within a static website: If you configure redirection in the static website feature, you may be redirected to another page when accessing index.html. Such redirects will not be recorded in the log.\n- Lifecycle transitions and deletions: If you configure the lifecycle to transition or delete objects after expiration, the operations of transitioning or deleting objects will be performed by the COS backend and will not be recorded in the log.\n- Operations of listing objects and uploading inventory reports: The inventory feature automatically lists all or specified objects in your buckets and delivers the generated inventory report to your buckets on a periodical basis. The operations of listing objects and delivering inventory reports will not be recorded in the log.\n- Operations of cross-region object replication: Cross-region replication involves getting an object from the source bucket and uploading it to the destination bucket. These operations are performed by the COS backend and will not be recorded in the log.\n- Object downloads in the COS Select feature: The COS Select feature allows you to extract an object which needs to be obtained from a storage device first. Object downloads are performed by the COS backend and will not be recorded in the log.\nOverview\n\nBy enabling versioning, you can store multiple versions of an object in the same bucket. For example, you can store multiple objects with the same object key “picture.jpg” in one bucket, but the objects have different version IDs such as 100000, 100101, and 120002. You can query, delete, or restore the objects by version ID. Versioning enables you to recover from data loss caused by accidental deletion or application failure. Versioning is ideal for the following scenarios:\n\n- If you need to delete objects (not permanently) in a versioning-enabled bucket, COS will insert delete markers for the deleted objects, and the markers will serve as the current object versions. You can restore an object to its previous version by the delete marker.\n- If you need to replace objects, COS will insert new version IDs for the added objects, and you can still restore the replaced objects by version ID.\n\nVersioning States\n\nThere are three versioning states for a bucket: not enabled, enabled, or suspended.\n\n- **Versioning not enabled**: bucket versioning is not enabled by default.\n- **Versioning enabled**: when bucket versioning is enabled, it will be applied to all the objects in the bucket. After versioning is enabled for the first time, objects added to the bucket thereafter will be assigned a unique version ID.\n- **Versioning suspended**: Once the versioning state is changed from enabled to suspended (versioning cannot be disabled once enabled), objects added to the bucket thereafter will no longer be subject to versioning.\n\nManaging Objects in Buckets with Different Versioning States\n\nYou can add, query, and delete objects in a bucket no matter what the versioning state is. When versioning is enabled or suspended, you can query and delete objects with or without version IDs.\n\n- If versioning is not enabled, you can add, query, and delete objects in the same way as in an ordinary bucket. For more information, see the Object Management.\n- If versioning is enabled or suspended, you can specify version IDs while retrieving and deleting objects. **Delete markers** will be added to deleted objects.\n\nManaging Objects in a Versioning-enabled Bucket\nFor objects in the bucket before versioning is enabled, their version ID will be “null”. Enabling versioning will change the way COS handles the objects, such as how COS makes requests, but not the objects themselves. Objects with the same name added thereafter will be stored in the same bucket with different version IDs. You can manage objects in a bucket with versioning enabled as described below:\n\nThe way you add objects to a bucket is the same for both buckets with versioning enabled and not enabled, but the objects added to the two types of buckets have different version IDs. If versioning is enabled, COS will assign a unique version ID to any object added to the bucket; if versioning is not enabled, the version ID will remain null.\n\nAdding Objects\n\nIf versioning is enabled for a bucket, when you perform PUT, POST, and COPY operations, COS will automatically assign a unique version ID to the objects added to the bucket.\n\nAs you can see below, when an object is added to a bucket with versioning enabled, COS will assign it a unique version ID.\n\nAdding Objects\n\nAs you can see below, when an object is added to a bucket with versioning enabled, COS will assign it a unique version ID.\n\nListing Versioned Objects\n\nCOS stores object version information in the versions parameter associated with the bucket and returns object versions in the order of storage time from the newest to the oldest.\n\nRetrieving All Versions of a Specific Object\n\nYou can retrieve all versions of a particular object using the versions parameter together with the prefix request parameter. For more information on prefix, see GET Bucket Object Versions. Below is a sample request for retrieving all versions of a specific object:\n\n```\nGET /?versions&prefix=ObjectKey HTTP/1.1\n```\n\nRetrieving Historical Versions of an Object\n\nA GET request with no version ID specified retrieves the current version of an object. The following figure shows how a GET request returns the current version (the latest version) of the 123.txt object.\nA GET request with a version ID specified retrieves the specified version of an object. The following figure shows how a GET versionId request returns the specified version of the object. The request can also retrieve the current version.\n\nRetrieving the Metadata of an Object Version\n\nIf you only want to retrieve the metadata of an object instead of its content, you can use the HEAD operation. By default, you get the metadata of the latest version. To retrieve the metadata of a specific object version, you need to specify its version ID when submitting the request.\n\nTo retrieve the metadata of an object version:\n\n- Set versionId to the ID of the version of the object whose metadata you want to retrieve.\n- Send a HEAD operation request with the versionId specified.\n\nDeleting Objects\n\nYou can delete unnecessary object versions whenever you want. When you make a DELETE request in a versioning-enabled bucket, there will be two scenarios:\n\n1. Perform a simple DELETE operation with no version ID specified.\n This is similar to putting the deleted objects to the \"recycle bin\". The objects are not permanently deleted and can be restored if needed.\n\n As you can see below, if you do not specify a version ID, the DELETE operation will not delete the 123.txt object; instead, it will\ninsert a delete marker and add a new version ID.\n\n\n\nCOS will insert a delete marker with a new version ID for the deleted objects. The delete marker will become the current version of the deleted objects. When you try to GET the objects with a delete marker, COS will assume that the objects do not exist and will return a 404 error.\n\n2. If you delete an object with a version ID specified, the specified version of the object will be deleted permanently.\n\n\n\n**Delete Marker**\n\nA delete marker is a marker for versioned objects, indicating that the objects have already been deleted in COS. A delete marker has an object key and version ID like any other object. However, a delete marker differs from other objects in the following ways:\n\n- Its content is empty.\n- It does not have ACL value.\n- If you try to GET a delete marker, you will get a 404 error with a response header of `x-cos-delete-marker: true`.\n- The only operation you can use on a delete marker is DELETE, and only the root account can issue such a request.\n\n**Deleting a Delete Marker**\n\nTo delete a delete marker, you can specify its version ID in a DELETE Object versionid request to permanently delete it. If you use a DELETE request to delete a delete marker without specifying its version ID, COS will not delete the delete marker, but instead, insert another delete marker.\nThe following figure shows how a simple DELETE on a delete marker removes nothing, but adds a new delete marker to a bucket.\n\nIn a versioning-enabled bucket, a new delete marker has a unique version ID. Therefore, one object may have multiple delete markers in the same bucket. To delete a delete marker permanently, you must include its version ID in a DELETE Object versionId request.\n\nThe following figure shows how you can permanently delete a delete marker with a DELETE Object versionId request.\n\nOnly the root account can delete a delete marker permanently.\n\nTo permanently remove a delete marker:\n\n1. Set versionId to the ID of the version of the delete marker you want to remove.\n2. Send a DELETE Object versionId request.\n\n**Restoring Previous Versions**\n\nVersioning can be used to restore previous versions. You can do it in two ways:\n\n1. Copy a previous version of the object into the same bucket\n The copied object will become the current version of the object, and all object versions will be retained\n2. Delete the current version of the object permanently\n When you delete the current object version, you, in effect, turn the previous version into the current version of the object.\n\n**Managing Objects in a Versioning-suspended Bucket**\nWhen you suspend versioning, existing objects in your bucket do not change. What changes is how COS handles objects in future requests. The section below describes how to manage objects in a bucket where versioning is suspended.\n\n**Adding Objects**\n\nOnce you suspend bucket versioning, when you use PUT, POST, or COPY operations, COS will automatically add a \"null\" version ID to objects added to the bucket thereafter as shown below:\n\nIf there are versioned objects in the bucket, the objects newly added to the bucket will become the current version with a version ID of null as shown below:\n\nIf there is already a null version in the bucket, it will be overwritten, and the original object content will also be replaced accordingly as shown below:\n\n**Retrieving Historical Versions of an Object**\n\nA GET Object request in a versioning-suspended bucket returns the current version of an object.\n\n**Deleting Objects**\n\nIf versioning is suspended, a DELETE request will result in one of the following:\n\n- If an object has a null version in the bucket, the null version of the object will be deleted.\n \n As you can see below, when you use a simple DELETE operation, COS will insert a delete marker for objects with a version ID of\nnull.\n\nSince a delete marker does not have content, you will lose the original content of the null version when a delete marker replaces it.\n\n- If an object does not have a null version in the bucket, a new delete marker will be added to the bucket. As you can see below, if an object does not have a null version in the bucket, a simple DELETE will not remove anything; COS will just insert a delete marker.\n\nEven in a bucket where versioning is suspended, the root account is still able to delete a specified version permanently. The following figure shows that deleting a specified object version will delete the object permanently.\nOnly the root account can delete a specified object version permanently.\nUsing Versioning\nVersioning Configuration\n\nLast updated: 2019-12-13 19:34:58\n\nUse Cases\n\nBy enabling versioning, you can store multiple versions of an object in a bucket and retrieve, delete, or restore a specified version. For more information, see Versioning Overview.\n\nOnly the root account and authorized sub-accounts can configure the versioning state of a bucket.\n\nDirections\n\nConfiguring via the COS Console\n\nYou can refer to Setting Versioning to learn how to encrypt objects in the console.\n\nConfiguring via REST API\n\nYou can use the REST API to configure versioning and manage objects in buckets with different versioning states. For more information, see the following API documentation:\n\n- PUT Bucket versioning\n- GET Bucket versioning\n- GET Bucket Object versions\n- PUT Object\n- GET Object\n- DELETE Object\n- DELETE Multiple Objects\n\nConfiguring with SDK\n\nYou can directly call the Versioning method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- Android SDK\n- C SDK\n- C++ SDK\n- .NET SDK\n- Go SDK\n- iOS SDK\n- Java SDK\n- JavaScript SDK\n- PHP SDK\n- Python SDK\nOverview\n\nWith a cross-region replication rule, COS can automatically and asynchronously replicate the new objects added to one bucket to another bucket in a different region. When cross-region replication is enabled, COS will accurately replicate the object content (such as object metadata and version ID) in the source bucket to the destination bucket, and the object copies contain exactly the same attribute information. Additionally, operations on the objects in the source bucket, such as adding or deleting, will also be synced to the destination bucket.\n\n- To enable cross-region replication, you need to make sure that the source and destination buckets are in different regions and both have versioning enabled.\n- After cross-region replication is enabled, the object copies will be of the same storage class as the source objects, unless you specify a different storage class for the object copies during replication.\n- During replication, COS will copy the access control list (ACL) of the source bucket. Currently, the source bucket and destination bucket must be in the same account.\n\nApplicable Scenarios\n\n- **Remote disaster recovery:** COS boasts 11 nines of availability for object data, but there is still a slight chance of data loss due to force majeure such as wars and natural disasters. If you want to avoid data loss by explicitly having a separate copy in a different region, you can use cross-region replication to achieve remote disaster recovery. In this way, when the IDC in one region is damaged due to force majeure, the IDC in the other region can still provide data copies for your use.\n- **Compliance:** COS ensures data availability by providing multiple copies and erasure codes for data in physical disks by default. However, there may be compliance requirements in some industries stipulating that you keep copies in another region. Cross-region replication allows data to be replicated across regions to meet such requirements.\n- **Access latency reduction:** when you have end users accessing objects from different regions, with cross-region replication, you can maintain object copies in the available storage regions closest to them, which can minimize access latency to deliver a better user experience.\n- **Special technical requirements:** if you have computing clusters in two different regions and the clusters need to process the same set of data, with cross-region replication, you can maintain object copies in both regions.\n- **Data migration and backup:** You can copy your business data from one availability region to another one as needed to implement data migration and backup.\n\nNotes\n\n**Replication Time**\n\nThe time it takes for COS to replicate objects depends on factors such as object size, distance between storage regions, and how the objects were uploaded. The time needed for synchronization may range from a few minutes to a few hours, subject to such factors.\n\n- Object size: it takes more time to replicate large objects, for which multipart upload is recommended for faster upload and synchronization.\nDistance between the source and destination regions: the farther the regions are away from each other, the longer it takes to transfer data.\n\nHow the objects were uploaded: unlike simple upload where data can only be uploaded or downloaded serially, multipart upload supports concurrent uploads which can speed up upload and cross-region replication of large files. For more information, see Simple Upload and Multipart Upload.\n\nLifecycle\nTo use cross-region replication, you need to enable versioning, which will keep multiple historical versions of objects in the buckets and result in more storage consumption. COS cross-region replication will incur fees for data requests, downstream traffic, and data storage. Among them, data storage is charged at the prices in the destination bucket region. If you want to reduce the costs or customize your data retention approach, you can do so through lifecycle management based on your business needs.\n\n- If you want the object copies in the destination bucket to follow the same lifecycle rule as those in the source bucket, create the same lifecycle rule in the destination bucket.\n- If you have set a lifecycle rule for the destination bucket, note that the creation time of the object copies generated by cross-region replication is the creation time of the source objects but not the time when the copies are replicated to the destination bucket.\n- If you have set a lifecycle rule in the source bucket and an object being replicated needs to be deleted according to the lifecycle rule, the object will still be replicated, and the object copy will be retained in the destination bucket.\n\nVersioning\nTo use cross-region replication, you need to enable versioning for both the source and destination buckets. For more information, see Versioning Overview. Once versioning is enabled, you should note that disabling it will affect cross-region replication:\n\n- If you try to disable versioning in a bucket where cross-region replication is enabled, COS will return an error prompting you to delete the cross-region replication rule before disabling versioning.\n- If you try to disable versioning in a destination bucket, COS will prompt you that cross-region replication will be affected if you do so. If you proceed to disable versioning, the cross-region replication rule that uses this bucket as the destination bucket will become invalid.\nThis document describes the content that will and will not be copied after you enable cross-region replication for a bucket.\n\nContent That Will Be Copied\n\nIn a source bucket with cross-region replication enabled, COS will copy the following:\n\n- Any new objects uploaded to the source bucket after the cross-region replication rule is added.\n- Object attribute information such as object metadata and version ID.\n- Information on object operations such as adding an object of the same name (equivalent to adding a new object) and deleting an object.\n\n- If you specify to delete an object version from the source bucket (i.e., specifying the version ID), this operation will not be copied.\n- If you add a bucket-level configuration such as a lifecycle rule to the source bucket, object operations caused by such configurations will not be copied to the destination bucket.\n\nDeletions with Cross-region Replication Enabled\n\nIf an object is deleted from a source bucket with cross-region replication enabled, the following will happen:\n\n- When a DELETE request is executed with no object version ID specified, COS will add a delete marker to the source bucket, and cross-region replication will copy the marker to the destination bucket. For more information on versioning and delete marker, see Versioning Configuration.\n- When a DELETE request is executed with an object version ID specified, COS will delete the specified object version from the source bucket but will not copy the deletion operation to the destination bucket, which means that COS will not delete the specified object version from the destination bucket. This can prevent malicious deletion of data.\n\nContents That Will Not Be Copied\n\nIn a source bucket with cross-region replication enabled, COS will not copy the following:\n\n- Objects that have already been in the bucket when cross-region replication is enabled, i.e., the legacy data.\n- Encrypted objects. COS does not copy encrypted data by default, but you can enable encrypted data replication by modifying the configuration information.\n- New object data added to the source bucket that is copied from another bucket.\n- Configuration updates at the bucket level.\n- Results from the execution of the lifecycle configuration.\n\n- The cross-region replication of object data between buckets is not transitive. If you set two cross-region replication rules, one of which sets bucket A as the source bucket and bucket B as the destination bucket, and the other sets bucket B as the source bucket and bucket C as the destination bucket, then the object data added to bucket A will only be copied to bucket B but not to bucket C.\n- For example, if you update the lifecycle configuration of the source bucket, COS will not apply this configuration to the destination bucket synchronously.\nIf you only configure a lifecycle rule for the source bucket, COS will add delete markers to expired objects there, but the markers will not be copied to the destination bucket. If you want the destination bucket to delete the expired objects, you need to configure the same lifecycle rule for the destination bucket separately.\nCross-region Replication Configuration\n\n\nApplicable Scenarios\n\nWith cross-region replication enabled, object data in your source bucket can be copied to the designated destination bucket in another region. Cross-region replication can help you achieve remote disaster recovery, comply with industry-specific requirements, migrate and back up data, reduce access latency, enable clusters in different regions to access data, etc.\n\nAfter versionning is enabled, newly uploaded objects will generate multiple versions and take up storage space, so these versions of the object will also charge for storage.\n\nDirections\n\n**Configuring via the COS Console**\n\nFor information on how to configure a cross-region replication rule in the COS Console, see Setting Cross-region Replication documentation.\n\n**Configuring via REST API**\n\nYou can configure and manage cross-region replication via REST API as described in the following API documentation:\n\n- PUT Bucket replication\n- GET Bucket replication\n- DELETE Bucket replication\n\n**Configuring with SDK**\n\nYou can directly call the cross-region replication method in the SDK. For more information, see the SDK documentation for the corresponding programming language below:\n\n- Android SDK\n- C SDK\n- C++ SDK\n- .NET SDK\n- Go SDK\n- iOS SDK\n- Java SDK\n- JavaScript SDK\n- PHP SDK\n- Python SDK\nData Security\n\nServer-side Encryption Overview\n\nOverview\n\nCOS encrypts your data at the object level before it is written to IDC disks and automatically decrypts the data when you access it. Encryption and decryption are completed on servers. Server-side encryption can effectively protect static data.\n\n- As long as you have access permission to objects, user experience is the same accessing encrypted and non-encrypted objects.\n- Server-side encryption only encrypts object data but not its metadata. Server-side encrypted objects can only be accessed with a valid signature, not by anonymous users.\n\nUse Cases\n\n- **Private data storage:** For private data storage, server-side encryption can encrypt stored data to protect your privacy and automatically decrypt the data when you access it.\n- **Private data transfer:** For private data transfer, COS supports deploying SSL certificates with HTTPS to implement encryption. An encryption layer will be established on the transfer linkage layer, ensuring that data will not be stolen or tampered with during transfer.\n\nEncryption\n\nCOS supports multiple server-side encryption methods such as SSE-COS and SSE-C. You can choose the appropriate one to encrypt data stored in COS.\n\n**SSE-COS Encryption**\n\nSSE-COS: Server-side encryption with a key managed by COS. In this mode, COS will manage the master key and data, and users can manage and encrypt the data directly through COS. SSE-COS uses a strong AES-256 multi-factor encryption to ensure that each object is encrypted with a unique key, while regularly rotating the master key to encrypt the key itself.\n\n- When uploading an object using the POST operation, you need to provide the same information in the form field. instead of providing the `x-cos-server-side-encryption-*` header. For more information, see POST Object.\n- SSE-COS encryption is not available for objects uploaded with a pre-signed URL. Instead, you need to use COS Console or HTTP request header to specify server-side encryption.\n\nUsing the COS Console\n\nYou can refer to Setting Object Encryption to learn how to encrypt objects in the console.\n\nUsing REST API\n\n- When you list objects in a bucket, all objects will be listed, no matter whether they are encrypted.\nWhen uploading an object using the POST operation, please provide the same information in the form field, instead of providing the request header. For more information, see POST Object.\n\nWhen you request the following APIs, you can apply server-side encryption by providing the `x-cos-server-side-encryption` header. For more information, see Common Request Headers - SSE-COS.\n\n- PUT Object\n- Initiate Multipart Upload\n- PUT Object - Copy\n- POST Object\n\n**SSE-COS Encryption**\n\nSSE-KMS encryption is server-side encryption using a key managed by KMS. KMS is a security management service launched by Tencent Cloud, using a third-party-certified hardware security module (HSM) to generate and protect keys. KMS allows users to easily create and manage keys, meeting their key management needs for multiple applications and services, while satisfying regulatory and compliance requirements.\n\nWhen using SSE-KMS encryption for the first time, you need to enable KMS service. After KMS service is enabled, the system will automatically create a default customer master key (CMK) for you. You can also create your own keys through KMS Console, define key policies and use methods, KMS allows users to choose their own key material from KMS or external sources, see Create Key and Import External Key.\n\n- SSE-KMS only encrypts the object data, not its metadata.\n- Currently, SSE-KMS only supports Beijing, Shanghai, and Guangzhou regions.\n- Using SSE-KMS encryption will incur additional cost, which will be charged by KMS, please see KMS Billing Overview for details.\n\n**Using the COS Console**\n\nYou can refer to Setting Object Encryption to learn how to encrypt objects in the console.\n\n**Using REST API**\n\n- When you list objects in a bucket, all objects will be listed, no matter whether they are encrypted.\n- When uploading an object using the POST operation, please provide the same information in the form field, instead of providing the request header. For more information, see POST Object.\n\nWhen you request the following APIs, you can apply server-side encryption by providing the `x-cos-server-side-encryption` header. For more information, see Common Request Headers - SSE-COS.\n\n- PUT Object\n- Initiate Multipart Upload\n- PUT Object - Copy\n- POST Object\n\n**Notes**\n\nIf you have never used COS console for SSE-KMS encryption, and only used API for SSE-KMS encryption, you need to create CAM Role first. The specific creation steps are as follows:\n\n1. Log into the CAM Console and go to the Roles page.\n2. Click [Create Role] and select the role entity as [Tencent Cloud Product Service].\n3. Select services supporting roles as [Object Storage], and then click [Next].\n\n4. Configure the role policy, find and select [QcloudKMSCreaterFullAccess], and then click [Next].\n5. Enter the specified role name: COS_QcsRole.\n\n6. Click [Done] to complete the creation.\n\n**SSE-C Encryption**\n\nSSE-C encryption is server-side encryption with a user-defined key. When you upload an object, COS will use the encryption key you provide to apply AES-256 encryption to your data.\n\n- COS does not store your encryption key. Instead, it stores the HMAC value of the encryption key with random data added, which is used to verify your request to access the object. COS cannot use the HMAC value to derive the value of the encryption key or decrypt the encrypted object. Therefore, if you lose the encryption key, the object cannot be obtained again.\n- When uploading an object using the `POST` operation, you need to provide the same information in the form field, instead of providing the `x-cos-server-side-encryption-*` header. For more information, see POST Object.\n- SSE-C can only be used via APIs but not the console.\n\n**Using REST API**\n\nWhen you request the following APIs, you can apply server-side encryption to `PUT` and `POST` requests by providing the `x-cos-server-side-encryption-*` header. For `GET` and `HEAD` requests, you need to provide the `x-cos-server-side-encryption-*` header to decrypt the specified object encrypted with SSE-C. For more information, see Common Request Headers - SSE-C. The following operations support this header:\n\n- GET Object\n- HEAD Object\n- PUT Object\n- Initiate Multipart Upload\n- Upload Part\n- POST Object\n- PUT Object - Copy\nBucket Encryption Overview\n\nOverview\n\nOnce a bucket is configured for encryption, all objects uploaded to the bucket thereafter will be encrypted by default with the specified encryption method.\n\nCurrently supported encryption methods include:\n\n- SSE-COS encryption: server-side encryption using COS-managed encryption keys\n\nFor more information on server-side encryption, please see Server-side Encryption Overview.\n\nDirections\n\nVia the COS Console\n\nYou can set bucket encryption in the COS Console. For more information, please see Setting Bucket Encryption in Console Guide.\n\nVia REST API\n\nYou can configure bucket encryption using the following APIs:\n\n- PUT Bucket encryption\n- GET Bucket encryption\n- DELETE Bucket encryption\n\nNotes\n\nUploading objects to an encrypted bucket\n\nFor buckets requiring encryption, note the following:\n\n- Configuring encryption for a bucket will not lead to encryption operations on objects that already exist in it.\n- After encryption is configured for a bucket, for objects uploaded to the bucket:\n - If your PUT request does not contain encryption information, the uploaded objects will be encrypted with the encryption configuration of the bucket.\n - If your PUT request contains encryption information, the uploaded objects will be encrypted with the contained encryption information.\n- After encryption is configured for a bucket, for inventory reports delivered to the bucket:\n - If encryption is not configured for the inventory, the delivered reports will be encrypted with the encryption configuration of the bucket.\n - If encryption is configured for the inventory, the delivered reports will be encrypted with the encryption configuration of the inventory.\n- After encryption is configured for the bucket, the data pulled back to the bucket will be encrypted with the encryption configuration of the bucket by default.\n\nEncrypting buckets that have cross-region replication rules configured\n\nFor the destination bucket that has a cross-region replication rule configured, if you configure encryption for it, note the following:\n\n- If the objects in the source bucket are not encrypted, the object copies in the destination bucket will be encrypted by default.\nIf the objects in the source bucket are encrypted, the object copies in the destination bucket will inherit the encryption from the source bucket, and the bucket encryption settings will not be honored.\nCloud Access Management (CAM)\nAccess Control\nBasic Concepts of Access Control\n\nLast updated: 2020-02-26 14:26:04\n\nConcept\n\nYou can grant access permissions by specifying a person to perform a specified action on specified resources under a specified condition. Generally, the following four elements are used to describe an access permission action: identity, resource, action, and condition (optional).\n\nElements for Access Permissions\n\n**Tencent Cloud’s identity**\n\nWhen you apply for a Tencent Cloud account, the system will create a root account for logging in to the Tencent Cloud services. The Tencent Cloud root account manages different types of users with different roles using the user management feature. User types include collaborator, message recipient, sub-user, and role. For more information, see CAM Identity Management and Glossary.\n\n**COS resources**\n\nBucket and Object are the basic resources of the COS service, and they have subresources associated with them.\n\nBucket’s subresources include:\n- acl and policy: access control information of a bucket\n- website: static website hosting configuration of a bucket\n- tagging: tag information of a bucket\n- cors: cross-origin configuration of a bucket\n- lifecycle: lifecycle configuration of a bucket\n\nObject’s subresources include:\n- acl: access control information of an object\n- restore: restore configuration of an archive object\n\n**COS operations**\n\nCOS provides a range of API operations on various resources. For more information, see Operation List.\n\n**CAM Overview**\n\n**Private principle**\n\nNote:\n\nBy default, all Tencent Cloud COS resources are private.\n- The resource owner (the Tencent Cloud root account creating a bucket resource) has the highest permission on the resource, and can grant access permissions to others or anonymous users by editing and writing an access policy.\n\n- When a Tencent Cloud CAM account is used to create a bucket or upload an object, its parent root account is the resource owner.\n\n- The root account of the bucket owner can authorize other Tencent Cloud root accounts to upload objects (i.e. cross-account upload). In this case, the object owner is still the root account of the bucket owner.\n\n**Access control policy**\n\n**Resource-based policy**\n\nTencent Cloud COS supports access control at both **bucket** and **object** dimensions, as detailed below:\n\n<table>\n<thead>\n<tr>\n<th>Dimension</th>\n<th>Type</th>\n<th>Language</th>\n<th>Supported Identity</th>\n<th>Supported Resource Granularity</th>\n<th>Supported Action</th>\n<th>Supported Effect</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Bucket</td>\n<td>Access policy language (Policy)</td>\n<td>JSON</td>\n<td>Sub-accounts, roles, Tencent Cloud services, other root accounts, anonymous users, etc.</td>\n<td>Buckets, objects, prefixes, etc.</td>\n<td>Each specific action</td>\n<td>Allow/Deny</td>\n</tr>\n<tr>\n<td>Bucket</td>\n<td>Access Control List (ACL)</td>\n<td>XML</td>\n<td>Other root accounts, anonymous users, etc.</td>\n<td>Buckets</td>\n<td>Read and write actions</td>\n<td>Allow</td>\n</tr>\n<tr>\n<td>Object</td>\n<td>Access Control List (ACL)</td>\n<td>XML</td>\n<td>Other root accounts, anonymous users, etc.</td>\n<td>Objects</td>\n<td>Read and write actions</td>\n<td>Allow</td>\n</tr>\n</tbody>\n</table>\n\n**Bucket Policy**\n\nA bucket policy is described in JSON language, and supports granting anonymous identities or any Tencent Cloud CAM account the permissions to access and perform operations on buckets and objects. In Tencent Cloud COS, the bucket policy can be used to manage almost all operations in the bucket. It is recommended that you use a bucket policy to manage access policies that cannot be described using ACLs.\n\nA Tencent Cloud root account has the highest permission on its resources (including buckets). Even if you can set limits on almost all operations in the bucket policy, the root account always has the permission for the PUT Bucket Policy operation, and can call this operation without checking the bucket policy.\n\nThe following policy allows anonymous users to access all objects in the bucket `examplebucket-1250000000` in Guangzhou, and to download all objects (GetObject) in the bucket without signature verification. In this case, any anonymous user who knows the URL can download the objects (similar to public-read):\n\n```json\n{\n \"Statement\": [\n {\n \"Principal\": \"*\",\n \"Effect\": \"Allow\",\n \"Action\": [\"cos:GetObject\"],\n \"Resource\": [\"qcs::cos:ap-guangzhou:uid/1250000000:examplebucket-1250000000/*\"]\n }\n ],\n \"Version\": \"2.0\"\n}\n```\nACL\n\nAn ACL is described in the XML language. It is a list of specified grantees and permissions granted, which is associated with resources. Each bucket and object has an associated ACL to grant basic read and write permissions to anonymous users or other Tencent Clouds root accounts.\n\nThe resource owner always has FULL_CONTROL permission on the resource, regardless of whether this is described in the issued ACL.\n\nThe bucket ACL in this example describes the full control permission of the bucket owner (UIN: 100000000001):\n\n```\n<AccessControlPolicy>\n <Owner>\n <ID>qcs::cam::uin/100000000001:uin/100000000001</ID>\n </Owner>\n <AccessControlList>\n <Grant>\n <Grantee xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:type=\"RootAccount\">\n <ID>qcs::cam::uin/100000000001:uin/100000000001</ID>\n </Grantee>\n <Permission>FULL_CONTROL</Permission>\n </Grant>\n </AccessControlList>\n</AccessControlPolicy>\n```\n\nThe object ACL in this example describes the full control permission of the object owner (UIN: 100000000001) and grants the read permission to all users (the public-read permission to anonymous users):\n\n```\n<AccessControlPolicy>\n <Owner>\n <ID>qcs::cam::uin/100000000001:uin/100000000001</ID>\n </Owner>\n <AccessControlList>\n <Grant>\n <Grantee>\n <ID>qcs::cam::uin/100000000001:uin/100000000001</ID>\n </Grantee>\n <Permission>FULL_CONTROL</Permission>\n </Grant>\n <Grant>\n <Grantee>\n <URI>http://cam.qcloud.com/groups/global/AllUsers</URI>\n </Grantee>\n <Permission>READ</Permission>\n </Grant>\n </AccessControlList>\n</AccessControlPolicy>\n```\n\nUser-based policy\n\nIn CAM, you can grant different permissions to different types of users under the root account.\n\nThe biggest difference between a user policy and a bucket policy is that the user policy only describes the effect, the action, the resource, and the condition (optional), and does not describe the identity (principal). Therefore, after you write a user policy, associate it with a sub-user, a user group or a role. Besides, the user policy does not support granting anonymous users the permissions to access resources and perform operations.\nYou can associate a preset policy for authorization, or write a user policy and associate it with a specified identity to manage access for your users.\n\nThe following policy example grants the permission to perform all COS operations on the bucket examplebucket-1250000000 in Guangzhou. You need to save the policy and then associate it with a CAM sub-user, a user group or a role before it takes effect.\n\n```json\n{\n \"Statement\": [\n {\n \"Effect\": \"Allow\",\n \"Action\": [\"cos:*\"],\n \"Resource\": [\n \"qcs::cos:ap-guangzhou:uid/1250000000:examplebucket-1250000000/*\",\n \"qcs::cos:ap-guangzhou:uid/1250000000:examplebucket-1250000000/\n ]\n }\n ],\n \"Version\": \"2.0\"\n}\n```\nNotes on Principle of Least Privilege\n\nLast updated : 2020-01-15 15:25:46\n\nOverview\n\nWhen using COS, you may need to use a temporary key to grant users permissions to certain resources or operations, configure user policies for your sub-users or collaborators that allow them to help you operate on the resources in COS, or create bucket policies that allow the specified users to perform certain operations on or access certain resources in your bucket. When configuring these permissions, please comply with the principle of least privilege in order to ensure the security of your data assets.\n\nThe principle of least privilege means that when granting permission, you must specify the scope of the permission granted to the specified user for performing what operation and access what resource under what conditions.\n\nPrecautions\n\nYou are recommended to strictly comply with the principle of least privilege to ensure that a user can only perform the specified operations (e.g., action:GetObject ) or access the specified resources (e.g., resource:exampleBucket-APPID/exampleObject.txt ). To prevent data security risks caused by unexpected and unauthorized operations with excessive permissions, it is strongly recommended that you avoid authorizing a user to access all resources (e.g., resource:* ) or perform all operations (e.g., action:* ).\n\nBelow are some potential data security risks:\n\n- Data leakage: if you want to authorize a user to download the specified resources such as examplebucket-1250000000/data/config.json and examplebucket-1250000000/video/ but include examplebucket-1250000000/* in the permission policy, then all objects in the bucket can be downloaded without your authorization, leading to unexpected data leakage.\n\n- Data overwriting: if you want to authorize a user to upload examplebucket-1250000000/data/config.json and examplebucket-1250000000/video/ but include examplebucket-1250000000/* in the permission policy, then all objects in the bucket can be uploaded without your authorization, which may overwrite unintended objects. To avoid this risk, in addition to following the principle of least privilege, you can retain all versions of data for traceability as instructed in Versioning Overview.\n\n- Permission leakage: if you want to authorize a user to list the objects in the bucket (cos:GetBucket ) but configured cos:* in the permission policy, then all operations on the bucket will be allowed, including reauthorizing the bucket, deleting objects, and deleting the bucket, which puts your data at extremely high risk.\n\nUsage Guide\n\nUnder the principle of least privilege, you should specify the following information in the policy:\n\n- principal: you should specify to which sub-account (user ID required), collaborator (user ID required), anonymous user, or user group to grant permission. This is not needed if you use a temporary key for access.\n\n- statement: enter the corresponding parameters.\n - effect: you must specify whether the policy is to \"allow\" or \"deny\".\n - action: you must specify the allowed or denied operation. An operation can be an API (described using the prefix \"name\") or a feature set (a set of specific APIs, described using the prefix \"permid\").\n - resource: you must specify the resource authorized by the policy. A resource is described in a six-piece format. You can set the resource scope as the specified file (e.g., exampleobject.jpg ) or the specified directory (e.g., examplePrefix/* ). Unless it is required by your business, please do not grant any user access to all resources using the * wildcard.\n - condition: it describes the condition for the policy to take effect. A condition consists of operator, action key, and action value. A condition value may contain information such as time and IP address.\n\nLeast privilege guide for temporary key\nWhen applying for a temporary key, you can set the permission policy field [Policy] to limit the permissions to operations and resources within the specific scope. For more information, please see Generating and Using Temporary Keys.\n\nAuthorization example\n\nGranting a user permission to access the specified object using the SDK for Java\n\nIf you want to use the SDK for Java to grant a user permission to download the `exampleObject.txt` object in the `examplebucket-1250000000` bucket, the configuration code should be as follows:\n\n```java\n// Import `java sts sdk` using the integration method with Maven as described on GitHub\nimport java.util.*;\nimport org.json.JSONObject;\nimport com.tencent.cloud.CosStsClient;\n\npublic class Demo {\n public static void main(String[] args) {\n TreeMap<String, Object> config = new TreeMap<String, Object>();\n\n try {\n // Replace with your own SecretId\n config.put(\"SecretId\", \"AKIDHTVVaVR6e3\");\n // Replace with your own SecretKey\n config.put(\"SecretKey\", \"PdkhT9e2rZCfy6\");\n\n // Validity period of the temporary key in seconds; default value: 1,800s; maximum value: 7,200s\n config.put(\"durationSeconds\", 1800);\n\n // Replace with your own bucket\n config.put(\"bucket\", \"examplebucket-1250000000\");\n // Replace with the region where your bucket resides\n config.put(\"region\", \"ap-guangzhou\");\n\n // Change it to the allowed path prefix such as `a.jpg`, `a/*`, or`*`. You can determine the specific path to which files can be uploaded based on your login status\n // If `*` is entered, the user will be allowed to access all resources; unless it is required by your business, please grant the user only the corresponding permission based on the principle of least privilege.\n config.put(\"allowPrefix\", \"exampleObject.txt\");\n\n // List of key permissions. The following permissions are required for simple upload, upload using a form, and multipart upload. For other permissions, please visit https://cloud.tencent.com/document/product/436/31923\n String[] allowActions = new String[] {\n \"name/cos:GetObject\"\n };\n config.put(\"allowActions\", allowActions);\n\n JSONObject credential = CosStsClient.getCredential(config);\n // If it succeeds, the temporary key information will be returned and printed out as shown below\n System.out.println(credential);\n } catch (Exception e) {\n // If it fails, an exception will be thrown\n throw new IllegalArgumentException(\"no valid secret!\");\n }\n }\n}\n```\n\nGranting a user permission to access the specified object using API\n\nIf you want to use an API to grant a user permission to download the `exampleObject.txt` object in the `examplebucket-1250000000` bucket and all objects in the `examplePrefix` directory, the access policy should be as follows:\nLeast privilege guide for user policy\n\nA user policy is a user permission policy created in the CAM Console to grant a user permission to access certain resources in COS. For more information, please see Access Policy Language Overview.\n\nAuthorization example\n\nGranting an account permission to access the specified object\n\nIf you want to grant an account whose UIN is 100000000001 permission to download the exampleObject.txt object in the examplebucket-1250000000 bucket, the access policy should be as follows:\n\n```json\n{\n \"version\": \"2.0\",\n \"principal\": {\n \"qcs\": [\"qcs::cam::uin/100000000001:uin/100000000001\"]\n },\n \"statement\": [\n {\n \"action\": [\"name/cos:GetObject\"],\n \"effect\": \"allow\",\n \"resource\": [\"qcs::cos:ap-guangzhou:uid/1250000000:examplebucket-1250000000.exampleObject.txt\"]\n }\n ]\n}\n```\n\nGranting a sub-account permission to access the specified directory\n\nIf you want to grant a sub-account whose UIN is 100000000011 (root account UNI: 100000000001) permission to download the objects in the examplePrefix directory in the examplebucket-1250000000 bucket, the access policy should be as follows:\n\n```json\n{\n \"version\": \"2.0\",\n \"principal\": {\n \"qcs\": [\"qcs::cam::uin/100000000001:uin/100000000001\"]\n },\n \"statement\": [\n {\n \"action\": [\"name/cos:GetObject\"],\n \"effect\": \"allow\",\n \"resource\": [\"qcs::cos:ap-guangzhou:uid/1250000000:examplebucket-1250000000,ap-guangzhou.myqcloud.com/exampleObject.txt\"]\n }\n ]\n}\n```\nLeast privilege guide for bucket policy\n\nA bucket policy is an access policy configured for a bucket to allow the specified user to perform certain operations on the bucket and resources in it. For more information, please see Adding Bucket Policies.\n\nAuthorization example\n\nGranting a sub-account permission to access the specified objects\n\nIf you want to grant a sub-account whose UIN is 100000000011 (root account UNI: 100000000001) permission to download the exampleObject.txt object in the examplebucket-1250000000 bucket and all objects in the examplePrefix directory, the access policy should be as follows:\n\n```json\n{\n \"Statement\": [\n {\n \"Action\": [\"name/cos:GetObject\"],\n \"Effect\": \"allow\",\n \"Principal\": {\n \"qcs\": [\"qcs::cam::uin/100000000001:uin/100000000011\"]\n },\n }\n ],\n \"version\": \"2.0\"\n}\n```\nPolicy-based Access Control\n\nAccess Policy Language Overview\n\nOverview\n\nAn access policy which employs the JSON-based access policy language is used to grant the access to COS resources. You can authorize a specified principal to perform actions on a specified COS resource through the access policy language.\n\nThe language describes the basic elements and usage of a bucket policy. For more information, see CAM Policy Management.\n\nElements in an Access Policy\n\nThe access policy language contains the following basic elements:\n\n- **Principal**: describes the entity to be authorized by the policy. This includes users (root accounts, sub-accounts, anonymous users), and user groups. This element can only be used in bucket access policies, rather than user access policies.\n- **Statement**: describes the detailed information of one or more permissions. This element includes a permission or a permission set of multiple elements such as effect, action, resource, and condition. A policy has only one statement.\n - **Effect**: Describes whether the result of the statement is \"allowed\" or \"explicitly denied\". This includes two situations: allow and deny. This element is required.\n - **Action**: Describes allowed or denied actions. An action can be an API (described using the prefix \"name\") or a feature set (a set of specific APIs, described using the prefix \"permid\"). This element is required.\n - **Resource**: Describes the detailed data of authorization. A resource is described in a six-piece format. Detailed resource definitions vary by product. For more information on how to specify a resource, see the documentation for the product whose resources you are writing a statement for. This element is required.\n - **Condition**: Describes the condition for the policy to take effect. A condition consists of operator, action key, and action value. A condition value may contain information such as time and IP address. Some services allow you to specify additional values in conditions. This element is optional.\n\nHow to Use Elements\n\nSpecifying a Principal\n\nA principal is used to specify the user, account, service, or entity that is allowed or disallowed to access resources. It only works in buckets and is not required in user policies because these policies are directly added to the specific user. The following example specifies a principal.\n\n```\n\"principal\": {\n \"qcs\": [\n \"qcs::cam::uin/100000000001:uin/100000000001\"\n ]\n}\n```\n\nGrant permissions to an anonymous user:\n\n```\n\"principal\": {\n \"qcs\": [\"qcs::cam::anonymous:anonymous\"]\n}\n```\nGrant permissions to a root account (UIN: 100000000001):\n\n```\n\"principal\": {\n \"qcs\": [\n \"qcs::cam::uin/100000000001:uin/100000000001\"\n ]\n}\n```\n\nGrant permissions to a sub-account (UIN: 100000000011) under the root account (UIN: 100000000001):\n\n```\n\"principal\": {\n \"qcs\": [\n \"qcs::cam::uin/100000000001:uin/100000000011\"\n ]\n}\n```\n\n**Specifying an Effect**\n\nIf you don't explicitly grant access to (allow) a resource, the access is implicitly denied. You can also explicitly deny access to a resource, which you might do to make sure that a user cannot access it, even if a different policy grants it access. The following example specifies an \"allow\" effect.\n\n```\n\"effect\": \"allow\"\n```\n\n**Specifying an Action**\n\nCOS defines COS actions that you can specify in a policy. The specified actions are just like initiation of API requests.\n\n### Actions on Buckets\n\n<table>\n<thead>\n<tr>\n<th>Description</th>\n<th>API</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>name/cos:GetService</td>\n<td>GET Service</td>\n</tr>\n<tr>\n<td>name/cos:GetBucket</td>\n<td>GET Bucket (List Object)</td>\n</tr>\n<tr>\n<td>name/cos:PutBucket</td>\n<td>PUT Bucket</td>\n</tr>\n<tr>\n<td>name/cos:DeleteBucket</td>\n<td>DELETE Bucket</td>\n</tr>\n</tbody>\n</table>\n\n### Actions on Objects\n\n<table>\n<thead>\n<tr>\n<th>Description</th>\n<th>API</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>name/cos:GetObject</td>\n<td>GET Object</td>\n</tr>\n<tr>\n<td>name/cos:PutObject</td>\n<td>PUT Object</td>\n</tr>\n<tr>\n<td>name/cos:HeadObject</td>\n<td>HEAD Object</td>\n</tr>\n<tr>\n<td>name/cos:DeleteObject</td>\n<td>DELETE Object</td>\n</tr>\n</tbody>\n</table>\n\"action\": [\n \"name/cos:GetObject\",\n \"name/cos:HeadObject\"\n]\n\n### Specifying a Resource\n\nA resource element describes one or multiple action objects including COS buckets and objects. All the resources can be described in the following six-piece format.\n\n```\nqcs:project_id:service_type:region:account:resource\n```\n\nParameter description:\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n<th>Required</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>qcs</td>\n<td>The abbreviation of qcloud service, which refers to Tencent Cloud services.</td>\n<td>Yes</td>\n</tr>\n<tr>\n<td>project_id</td>\n<td>Describes the project information, which is only used to enable compatibility with legacy CAM logic.</td>\n<td>No</td>\n</tr>\n<tr>\n<td>service_type</td>\n<td>Describes the abbreviation of the product such as COS.</td>\n<td>Yes</td>\n</tr>\n<tr>\n<td>region</td>\n<td>Describes the region information. For more information, see <a href=\"#\">Regions & Endpoints</a> supported by Tencent Cloud COS.</td>\n<td>Yes</td>\n</tr>\n<tr>\n<td>account</td>\n<td>Describes the root account information of the resource owner. “uin” and “uid” can be used to describe a resource owner. The former is QQ number of the root account in the format of <code>uin/${OwnerUin}</code>, such as <code>uin/100000000001</code>. The latter is APPID of the root account in the format of <code>uid/${appid}</code>, such as <code>uid/1250000000</code>. For now, COS resource owner is always described using uid, i.e., the APPID of the root account.</td>\n<td>Yes</td>\n</tr>\n<tr>\n<td>resource</td>\n<td>Describes the detailed resource information. In COS, a resource is described using the bucket XML API access domain name.</td>\n<td>Yes</td>\n</tr>\n</tbody>\n</table>\n\nThe following example specifies the bucket examplebucket-1250000000.\n\n```\n\"resource\": [\"qcs::cos:ap-guangzhou:uid/1250000000:examplebucket-1250000000/*\"]\n```\n\nThe following example specifies all objects in the `/folder/` folder in the bucket examplebucket-1250000000.\n\n```\n\"resource\": [\"qcs::cos:ap-guangzhou:uid/1250000000:examplebucket-1250000000/folder/*\"]\n```\n\nThe following example specifies the `/folder/exampleobject` object in the bucket examplebucket-1250000000.\n\n```\n\"resource\": [\"qcs::cos:ap-guangzhou:uid/1250000000:examplebucket-1250000000/folder/exampleobject\"]\n```\n\n### Specifying a Condition\n\nThe access policy language allows you to specify conditions when granting permissions, such as limiting the access source of a user or the authorization time. The list below contains supported conditional operators as well as general condition keys and examples.\n\n<table>\n<thead>\n<tr>\n<th>Conditional Operator</th>\n<th>Meaning</th>\n<th>Condition Name</th>\n<th>Example</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Ip_equal</td>\n<td>IP is equal to</td>\n<td>qcs:ip</td>\n<td>{"ip_equal":{"qcs:ip ":"10.121.2.0/24"}}</td>\n</tr>\n<tr>\n<td>Ip_not_equal</td>\n<td>IP is not equal to</td>\n<td>qcs:ip</td>\n<td>{"ip_not_equal":{"qcs:ip":["10.121.1.0/24","10.121.2.0/24"]}}</td>\n</tr>\n</tbody>\n</table>\n### Conditional Operator\n\n<table>\n<thead>\n<tr>\n<th>Operator</th>\n<th>Meaning</th>\n<th>Condition Name</th>\n<th>Example</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>date_not_equal</td>\n<td>Time is not equal to</td>\n<td>qcs:current_time</td>\n<td>{"date_not_equal":{"qcs:current_time":"2016-06-01T00:01:00Z"}}</td>\n</tr>\n<tr>\n<td>date_greater_than</td>\n<td>Time is greater than</td>\n<td>qcs:current_time</td>\n<td>{"date_greater_than":{"qcs:current_time":"2016-06-01T00:01:00Z"}}</td>\n</tr>\n<tr>\n<td>date_greater_than_equal</td>\n<td>Time is greater than</td>\n<td>qcs:current_time</td>\n<td>{"date_greater_than_equal":{"qcs:current_time":"2016-06-01T00:01:00Z"}}</td>\n</tr>\n<tr>\n<td>date_less_than</td>\n<td>Time is less than</td>\n<td>qcs:current_time</td>\n<td>{"date_less_than":{"qcs:current_time":"2016-06-01T00:01:00Z"}}</td>\n</tr>\n<tr>\n<td>date_less_than_equal</td>\n<td>Time is less than</td>\n<td>qcs:current_time</td>\n<td>{"date_less_than_equal":{"qcs:current_time":"2016-06-01T00:01:00Z"}}</td>\n</tr>\n</tbody>\n</table>\n\nThe following example specifies that the access IP is within the IP range of 10.121.2.0/24.\n\n`\"ip_equal\":{\"qcs:ip\":\"10.121.2.0/24\"}`\n\nThe following example specifies that the access IPs are 101.226.***.185 and 101.226.***.186.\n\n`\"ip_equal\": { \"qcs:ip\": [ \"101.226.***.185\", \"101.226.***.186\" ] }`\n\n### Examples\n\nIf, when the access source IPs are 101.226.***.185/101.226.***.186, the root account allows anonymous users to perform GET (download) and HEAD actions on the objects in the bucket examplebucket-1250000000 in South China, no authentication is required. For more information, see [Cases of Permission Setting](#).\n\n```json\n{\n\"version\": \"2.0\",\n\"principal\": {\n \"qcs\": [ \n \"qcs::cam::anonymous:anonymous\"\n ],\n \"statement\": [\n \"action\": [ \n \"name/cos:GetObject\",\n \"name/cos:HeadObject\"\n ],\n \"condition\": { \n \"ip_equal\": { \n \"qcs:ip\": [ \n \"101.226.***.185\",\n \"101.226.***.186\"\n ]\n }\n }\n ]\n}\n```\n\"effect\": \"allow\",\n\"resource\": [\n \"qcs::cos:ap-guangzhou:uid/1250000000:examplebucket-1250000000.ap-guangzhou.myqcloud.com/*\"\n]\n]\nExamples of Bucket Policies\n\nOverview\n\nThis document describes examples of bucket policies used to limit subnets, principals, and VPC ID. You can use these bucket policies to control specific access to the bucket and its data. For more information, see Access Policy Language Overview.\n\n- When configuring a bucket policy in the COS Console, you need to grant users appropriate permissions to the bucket, for example, getting the bucket location, and listing the bucket permissions.\n- The bucket policy size is limited to 20 KB.\n\nExample 1: Limit the IP range in the subnet to 10.1.1.0/24 and vpcid to aqp5jrc1.\n\nSyntax example:\n\n```\n{\n \"Statement\": [\n { \"Action\": [\n \"name/cos:*\"\n ],\n \"Condition\": {\n \"ip_equal\": {\n \"qcs:ip\": [ \"10.1.1.0/24\" ]\n },\n \"string_equal\": {\n \"vpc:requester_vpc\": [ \"vpc-aqp5jrc1\" ]\n }\n },\n \"Effect\": \"deny\",\n \"Principal\": {\n \"qcs\": [ \"qcs::cam::anyone:anyone\" ]\n },\n \"Resource\": [ \"qcs::cos:ap-guangzhou:uid/1251668577:jimmyyantest-1251668577/*\" ]\n },\n \"version\": \"2.0\"\n}\n```\n\nExample 2: Limit vpcid to aqp5jrc1 and specify the principal and bucket.\n\nSyntax example:\n\n```\n{\n \"Statement\": [\n {\n \"Action\": [ \"name/cos:*\" ],\n \"Condition\": {\n \"string_equal\": {\n \"vpc:requester_vpc\": [ \"vpc-aqp5jrc1\" ]\n }\n },\n \"Effect\": \"allow\",\n \"Principal\": { \"qcs\": [ \"qcs::cam::anyone:anyone\" ] },\n \"Resource\": [ \"qcs::cos:ap-guangzhou:uid/1251668577:jimmyyantest-1251668577/*\" ]\n }\n ],\n \"version\": \"2.0\"\n}\n```\n\"Action\": [ \"name/cos:*\" ],\n\"Condition\": { \"string_equal\": { \"vpc:requester_vpc\": [ \"vpc-aqp5jrc1\" ] } },\n\"Effect\": \"allow\",\n\"Principal\": { \"qcs\": [ \"qcs::cam::uin/3280754170:uin/100005212150\" ] },\n\"Resource\": [ \"qcs::cos:ap-beijing:uid/1252921383:x3cmplay-1252921383/*\" ] },\n\"version\": \"2.0\"}\nConcept\n\nAn ACL is described in the XML language. It is a list of specified grantees and permissions granted, which is associated with resources. Each bucket and object has an associated ACL to grant basic read and write permissions to anonymous users or other Tencent Clouds root accounts.\n\nHere are some limits on the use of ACLs associated with resources.\n\n- The resource owner always has FULL_CONTROL permission on the resource, which cannot be revoked or modified.\n- An anonymous user cannot be the resource owner. In this case, the object owner is the bucket owner (Tencent Cloud root account).\n- Permissions can only be granted to Tencent Cloud CAM root accounts or anonymous users, rather than sub-users or user groups.\n- No conditions should be imposed on the permissions.\n- \"Deny\" permission is not supported.\n- A resource can have up to 100 ACL policies.\n\nACL Elements\n\nIdentity (Grantee)\n\nA supported grantee can be a CAM root account or a preset CAM user group.\n\n- When you grant access permissions to another Tencent Cloud root account, this root account can grant access permissions to its sub-users, user groups or roles.\n- In COS, it is strongly recommended not to grant WRITE, WRITE_ACP or FULL_CONTROL permission to any anonymous user or CAM user group. Otherwise, the user group can upload, download or delete your resources, which will bring security risks to your account, such as data loss and fee deduction.\n\nGrantees supported in bucket or object ACLs include:\n\n- Cross-account: Use the root account ID to get the \"Account ID\" in Account Info, e.g. 388628665.\n- Preset user group: Tag a preset user group using a URI tag. The following user groups are supported:\n - Anonymous user group - http://cam.qcloud.com/groups/global/AllUsers, which indicates that anyone can access resources without authorization, regardless of whether the request is signed or unsigned.\n - Certified User Group - http://cam.qcloud.com/groups/global/AuthenticatedUsers, which indicates that users that have registered a Tencent Cloud CAM account can access resources.\n\nAction permissions\n\nTencent Cloud COS supports a range of action sets on resource ACLs, which include different actions on bucket ACLs and object ACLs respectively.\n\nActions on buckets\nHere is a list of actions supported in the bucket ACLs:\n\n<table>\n<thead>\n<tr>\n<th>Action Set</th>\n<th>Description</th>\n<th>Allowed Actions</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>READ</td>\n<td>Lists objects</td>\n<td>GetBucket, HeadBucket, GetBucketObjectVersions, ListMultipartUploads</td>\n</tr>\n<tr>\n<td>WRITE</td>\n<td>Uploads, overwrites and deletes objects</td>\n<td>PutObject, PutObjectCopy, PostObject, InitiateMultipartUpload, UploadPart, UploadPartCopy, CompleteMultipartUpload, DeleteObject</td>\n</tr>\n<tr>\n<td>READ_ACP</td>\n<td>Reads bucket ACLs</td>\n<td>GetBucketAcl</td>\n</tr>\n<tr>\n<td>WRITE_ACP</td>\n<td>Writes to bucket ACLs</td>\n<td>PutBucketAcl</td>\n</tr>\n<tr>\n<td>FULL_CONTROL</td>\n<td>A collection of the above sets</td>\n<td>A collection of the above actions</td>\n</tr>\n</tbody>\n</table>\n\nPlease proceed with caution when you grant WRITE, WRITE_ACP or FULL_CONTROL permission on buckets. Granting the WRITE permission will allow the grantee to overwrite or deleted any existing object.\n\nActions on objects\n\nHere is a list of actions supported in the object ACLs:\n\n<table>\n<thead>\n<tr>\n<th>Action Set</th>\n<th>Description</th>\n<th>Allowed Actions</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>READ</td>\n<td>Reads objects</td>\n<td>GetObject, GetObjectVersion, HeadObject</td>\n</tr>\n<tr>\n<td>READ_ACP</td>\n<td>Reads object ACLs</td>\n<td>GetObjectAcl, GetObjectVersionAcl</td>\n</tr>\n<tr>\n<td>WRITE_ACP</td>\n<td>Writes to object ACLs</td>\n<td>PutObjectAcl, PutObjectVersionAcl</td>\n</tr>\n<tr>\n<td>FULL_CONTROL</td>\n<td>A collection of the above sets</td>\n<td>A collection of the above actions</td>\n</tr>\n</tbody>\n</table>\n\nThe WRITE operation set is not supported for objects.\n\nPreset ACL\n\nTencent Cloud COS supports a group of preset ACLs for authorization, making it much easier to describe simple permissions. When using a preset ACL for description, you need to put the `x-cos-acl` header in the PUT Bucket/Object or PUT Bucket/Object ACL and describe the required permission. If an XML description is also carried in the request body, the description in the header is used and the XML description in the request body is ignored.\n\n### Preset ACLs for buckets\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>private</td>\n<td>The creator (root account) has the FULL_CONTROL permission, while others have no permissions. (Default)</td>\n</tr>\n<tr>\n<td>public-read</td>\n<td>The creator has the FULL_CONTROL permission, and the anonymous user group has the READ permission.</td>\n</tr>\n<tr>\n<td>public-read-write</td>\n<td>Both the creator and the anonymous user group have the FULL_CONTROL permission, which is generally not recommended.</td>\n</tr>\n<tr>\n<td>authenticated-read</td>\n<td>The creator has the FULL_CONTROL permission, and the certified user group has the READ permission.</td>\n</tr>\n</tbody>\n</table>\n\n### Preset ACLs for objects\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>default</td>\n<td>An empty description. The request follows the bucket or sub-user policy explicitly allowed. No declaration means deny.</td>\n</tr>\n<tr>\n<td>private</td>\n<td>The creator (root account) has the FULL_CONTROL permission, while others have no permissions.</td>\n</tr>\n<tr>\n<td>public-read</td>\n<td>The creator has the FULL_CONTROL permission, and the anonymous user group has the READ permission.</td>\n</tr>\n<tr>\n<td>authenticated-read</td>\n<td>The creator has the FULL_CONTROL permission, and the certified user group has the READ permission.</td>\n</tr>\n<tr>\n<td>bucket-owner-read</td>\n<td>The creator has the FULL_CONTROL permission, and the bucket owner has the READ permission.</td>\n</tr>\n<tr>\n<td>bucket-owner-full-control</td>\n<td>Both the creator and the bucket owner have the FULL_CONTROL permission.</td>\n</tr>\n</tbody>\n</table>\n\nThe public-read-write permission is not supported for objects.\n\n**Example**\n\n**Bucket ACL**\n\nWhen you create a bucket, COS creates a default ACL to grant the resource owner the full control over the resource (FULL_CONTROL), as shown in the following example:\n\n```xml\n<AccessControlPolicy>\n <Owner>\n <ID>Owner-Cononal-CAM-User-Id</ID>\n </Owner>\n <AccessControlList>\n <Grant>\n <Grantee>\n <ID>Owner-Cononal-CAM-User-Id</ID>\n </Grantee>\n <Permission>FULL_CONTROL</Permission>\n </Grant>\n </AccessControlList>\n</AccessControlPolicy>\n```\n\n**Object ACL**\n\nWhen you create an object, COS does not create an ACL by default, and the object owner is the bucket owner. The object's permissions inherited from its bucket are the same with the access permissions of the bucket. Since the object does not have a default ACL, it will follow the definition of visitors and behaviors in the bucket policy to determine if the request is granted. For more information, see Access Policy Language Overview.\n\nIf you need to grant additional access permissions to the object, you can add more ACLs to describe the access permissions of the object. For example, grant an anonymous user the permission to read a single object, as shown below:\n\n```xml\n<AccessControlPolicy>\n <Owner>\n <ID>Owner-Cononal-CAM-User-Id</ID>\n </Owner>\n <AccessControlList>\n <Grant>\n <Grantee>\n <ID>Owner-Cononal-CAM-User-Id</ID>\n </Grantee>\n </Grant>\n </AccessControlList>\n</AccessControlPolicy>\n```\n<Grantee>\n <ID>Owner-Canonical-CAM-User-Id</ID>\n</Grantee>\n<Permission>FULL_CONTROL</Permission>\n</Grant>\n<Grant>\n <Grantee>\n <URI>http://cam.qcloud.com/groups/global/AllUsers</URI>\n </Grantee>\n <Permission>READ</Permission>\n</Grant>\n</AccessControlList>\n</AccessControlPolicy>\nTag-based Access Control\nManage project resources based on tags\n\nLast updated: 2020-02-16 17:42:27\n\nNote\n\nThis document mainly introduces how to use tags and tag authentication to manage project resources under the tag system, which is suitable for some old users who have used projects on the historical version console, and grant sub-accounts Access and Permission through project authentication.\n\nProject management is the centralized management of resources based on the project dimension. You can add Tencent Cloud services resources that support project features to the project, and through the Access Management console Generate project strategy from [Policy] > [Create Custom Policy] > [create by Features or Project Permission] in. You can apply project policy Associate to project-related users or user groups to allow users or user groups to own the operation of project resources, Permission.\n\nCOS provides users with relevant Permission management operations on the historical version console based on the project, but the project strategy includes complete Access and Permission for all resources under all products added to the project, not only Unable to meet the needs of multi-dimensional marking and classification, also Unable to carry out meticulous management of Permission. In the new version of COS console, COS only supports Permission management of project resources based on tags.\n\nCOS uses the tagging service to make the original project functionality compatible. Under the system of tag service, an item is a special label, and its label key is project. You can still create Bucket in the project console, Create project and under the project. COS will automatically write a copy of Bucket's project ownership relationship into the tag when you create Bucket for display on the console.\n\n- If you have a need for classified management of Bucket, we recommend that you manage your Bucket directly through tags to achieve Permission control and account sharing, such as job, rather than through the project. For information about how to add tags to the console, see Set Bucket tag.\n- For more information about the project, see CAM's Items and labels For more information about tagging services, see Tags Product Documentation.\n\nAccess Permission, who owns the project under the sub-account.\n\nAccess Permission, who owns the project under the sub-account, can follow the following steps:\n\n1. Login Project management console Create a project, customize the project name and submit, and then select to create a resource such as Bucket or Cloud Virtual Machine under the project. If you already have a project and the project already has storage or computing resources to which it belongs, you can skip this step.\n\n2. After you have created the project and bound the corresponding resources, enter Policy Management On the page, click * * Create Custom Policy * *-> * * authorize by tag * * You can select the tag authentication method, select the corresponding project tag, and grant all the resources signed by the sub-account Access to the target.\n\n3. The default policy is to grant all resources signed by the sub-account Access to this target. If you only want the user to specify only some of the resources under the tag, you can see Grammatical structure Documents, modifying policy syntax for action (set the specified action) and resource (set actionable resources), and then click \"finish\".\n4. If you want the sub-account to be able to create Bucket, you also need to grant \\( \\text{PUT Bucket} \\). The operation of Permission. You can go to Policy Management Click \"Create Custom Policy\"-\"create by Policy Builder\" on the page, and authorize the corresponding Permission of the sub-account.\nUsing CDN to Accelerate Access\n\nCDN Acceleration Overview\n\nLast updated: 2019-06-14 18:47:58\n\nAccelerating COS with CDN allows you to mass download and deliver the content in a bucket, especially in the use cases where the same content is repeatedly downloaded. With the origin-pull authentication feature, the delivery of content in a Public-Read bucket can be accelerated using CDN, and with the CDN authentication feature, the content can only be downloaded by legitimate users, thus avoiding data security problem and high traffic cost caused by unrestricted download access.\n\nContent Delivery Network (CDN)\n\nDefinition of CDN\n\nContent Delivery Network (CDN) is a layer of network architecture built on the Internet that is composed of globally distributed servers which work together to provide faster delivery of Internet content. These high-performance cache nodes store your Internet content based on a certain caching policy. When your user makes a request for your Internet content, the request will be routed to the server closest to the user. Then the server responds to the request directly, greatly reducing the user’s access delay and improving availability.\n\nCaching and origin-pull will occur on a CDN. When a user accesses a URL, if the requested content is not cached on the edge server to which the access request is directed, or the cached content has expired, the request will be returned to the origin server to get the content.\n\nUse cases\n\n- Scenarios with high requirements for response delay and download speed.\n- Scenarios where cross-region, cross-border or cross-continent data transfer reaching GB or TB-level is required.\n- Scenarios where the same content needs to be downloaded frequently.\n\nSecurity options\n\n- Origin-pull authentication: If the data requested by a user is not cached in the edge server, CDN fetches the data from the origin server. If COS is used as the origin server and origin-pull authentication is enabled, the CDN edge server accesses the COS origin server using a special service identity to acquire and cache the data in the private bucket.\n- CDN service authorization: A CDN edge server can access the COS origin server with a special service identity by adding a CDN service authorization. Origin-pull authentication can only be enabled after the CDN service authorization is added.\n- CDN authentication: When a user attempts to acquire cached data by accessing an edge server, the edge server verifies the authentication field in the accessed URL based on the authentication configuration rules to prevent unauthorized access and realize hotlink protection, thus improving the security and reliability of the data cached in the edge server.\n\nAccess Nodes of COS\n\nDefinition of access node\n\nAn access node is an access domain name that is assigned to a bucket based on the region and name of the bucket when it is created. The domain name can be used to access the data in the bucket.\n\nIf the static website feature is enabled, you can get an access node for a static website to present the specially configured response content that is different from that of the default node.\n• XML node: After a bucket is created, COS assigns an XML access node to the bucket, such as `<bucketname>-<APPID>.cos.<region>.myqcloud.com`. It is suitable for RESTful API calls. With an XML access node, you can configure a bucket or upload/download objects as described in API documentation.\n\n• Static website node: You can enable the static website hosting feature in the basic configuration interface of bucket in the console. After the feature is enabled, an access node in the form of `<bucketname>-<APPID>.cos-website.<region>.myqcloud.com` is provided. Static websites support special index pages (IndexPage), error pages (ErrorPage), and redirects, and only allow the download of objects. You can obtain content through static website nodes.\n\n**Access permissions**\n\n• Public Read: When a bucket is set to \"Public Read\", anyone can access it using the bucket's access domain name. If you use a public-read bucket as the origin server, you can enable CDN acceleration directly without using CDN authentication and origin-pull authentication.\n\n• Private Read: When a bucket is set to \"Private Read\", you can manage accessing users and CDN service authorizations by creating access policies. When you use a private-read bucket as the origin server, if origin-pull authentication is enabled but CDN authentication is not, unauthorized users can access the bucket via CDN. Therefore, it is highly recommended to enable both origin-pull authentication and CDN authentication for private-read buckets to ensure the data security.\n\n**Accelerating Access to COS Using CDN**\n\nYou can accelerate access to COS by managing the following two domain names:\n\n• Default accelerated domain name: COS provides a default CDN accelerated domain name (such as `<bucketname>-<APPID>.file.mycloud.com`). You can enable or disable it at your option.\n\n• Custom domain name: You can use a custom domain name which has gone through ICP filing, with a COS bucket as the origin server. This allows you to accelerate the access to the objects in the bucket with your custom domain name.\n\n**Notes:**\nDefault accelerated domain name and custom domain name can be collectively referred to as CDN accelerated domain names.\n\n**Public-read buckets**\n\nWhen a bucket is set to allow public access, and the CDN origin server is set to the COS access node, the CDN edge servers can acquire and cache the object data in the bucket without you enabling origin-pull authentication.\n\nYou can provide **limited** protection for the data in the bucket by enabling Authentication Configuration in the CDN Console. This is because that regardless of whether this feature is enabled in the CDN, the users who know the bucket access domain name can access all objects in the bucket. Whether the access to public-read buckets is possible via different domain names when CDN authentication is enabled or disabled is as follows:\n\n<table>\n<thead>\n<tr>\n<th>CDN Authentication</th>\n<th>CDN Accelerated Domain Name</th>\n<th>COS Domain Name</th>\n<th>Scenarios</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Disabled (default)</td>\n<td>Yes</td>\n<td>Yes</td>\n<td>Public access to the entire website via CDN or origin server is allowed.</td>\n</tr>\n<tr>\n<td>Enabled</td>\n<td>URL authentication is required</td>\n<td>Yes</td>\n<td>Hotlink protection is enabled for access via CDN access, but not for access via origin server (not recommended)</td>\n</tr>\n</tbody>\n</table>\n\n**Private-read buckets**\n\n©2013-2019 Tencent Cloud. All rights reserved.\nWhen a bucket defaults to Private Read, and the CDN origin server is set to the COS access node, the CDN edge nodes are **unable to get and cache any data**. Therefore, you need to add the CDN service identity to the Bucket Policy and authorize the identity to perform the following operations:\n\n- **GET Object** - Acquire objects.\n- **HEAD Object** - Acquire the metadata of objects.\n- **OPTIONS Object** - Initiate a preflight request.\n\nYou can complete quick authorization in both the CDN Console and the COS Console by simply clicking **Add CDN Service Authorization**. Then you need to enable **Origin-Pull Authentication**. After that, a CDN edge server can access the data in the COS with its service identity.\n\n### Notes:\n\n1. If the bucket is set to Private Read, you must add an authorization and enable origin-pull authentication, otherwise COS will deny the access to it.\n2. A CDN edge server will generate a unique service account for each root account. Therefore, the account authorization is only valid for the root account to which the accelerated domain name belongs. Cross-account binding of an accelerated domain name will cause the access via the domain name to be denied.\n\nAfter the CDN service authorization is added and origin-pull authentication is enabled, the CDN edge nodes are able to directly get and cache the data. Therefore, it is highly recommended to enable Authentication Configuration to protect the private data in a bucket. Whether the access to private-read buckets is possible via different domain names when CDN authentication is enabled or disabled is as follows:\n\n<table>\n<thead>\n<tr>\n<th>CDN Authentication</th>\n<th>CDN Accelerated Domain Name</th>\n<th>COS Domain Name</th>\n<th>Scenarios</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Disabled (default)</td>\n<td>Yes</td>\n<td>COS authentication is required</td>\n<td>Direct access to CDN domain names is allowed to protect the data on origin server.</td>\n</tr>\n<tr>\n<td>Enabled</td>\n<td>URL authentication is required</td>\n<td>COS authentication is required</td>\n<td>Full stack strict SSL secured connection. Hotlink protection for CDN authentication is supported.</td>\n</tr>\n</tbody>\n</table>\nCDN Acceleration Configuration\n\nLast updated: 2019-09-30 18:09:01\n\nApplicable Scenarios\n\n- Scenarios that require low latency and high download speed.\n- Scenarios where gigabytes to terabytes of data need to be transmitted across regions, countries, and continents.\n- Scenarios where the same content needs to be downloaded frequently and repeatedly.\n\nNotes\n\nFor information on domain name definition, CDN origin-pull authentication, and CDN authentication configuration, see CDN Acceleration Overview.\n\nCDN origin-pull authentication and CDN authentication configuration affect how CDN accelerated domain names and COS domain names access origin server buckets. Please find the details in the table below.\n\n<table>\n<thead>\n<tr>\n<th>Bucket Access Permission</th>\n<th>CDN Origin-pull Authentication</th>\n<th>CDN Authentication Configuration</th>\n<th>CDN Accelerated Domain Name</th>\n<th>COS Domain Name</th>\n<th>Scenario</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Public read</td>\n<td>Disabled</td>\n<td>Disabled</td>\n<td>Accessible</td>\n<td>Accessible</td>\n<td>Site-wide public access</td>\n</tr>\n<tr>\n<td>Public read</td>\n<td>Enabled</td>\n<td>Disabled</td>\n<td>Accessible</td>\n<td>Accessible</td>\n<td>Not recommended</td>\n</tr>\n<tr>\n<td>Public read</td>\n<td>Disabled</td>\n<td>Enabled</td>\n<td>URL authentication required</td>\n<td>Accessible</td>\n<td>Not recommended</td>\n</tr>\n<tr>\n<td>Public read</td>\n<td>Enabled</td>\n<td>Enabled</td>\n<td>URL authentication required</td>\n<td>Accessible</td>\n<td>Not recommended</td>\n</tr>\n<tr>\n<td>Private read + CDN service authorization</td>\n<td>Enabled</td>\n<td>Enabled</td>\n<td>URL authentication required</td>\n<td>COS authentication required</td>\n<td>Full-linkage protection</td>\n</tr>\n<tr>\n<td>Private read + CDN service authorization</td>\n<td>Disabled</td>\n<td>Enabled</td>\n<td>Inaccessible</td>\n<td>COS authentication required</td>\n<td>Not recommended</td>\n</tr>\n<tr>\n<td>Private read + CDN service authorization</td>\n<td>Enabled</td>\n<td>Disabled</td>\n<td>Accessible</td>\n<td>COS authentication required</td>\n<td>Origin server protection</td>\n</tr>\n<tr>\n<td>Private read + CDN service authorization</td>\n<td>Disabled</td>\n<td>Disabled</td>\n<td>Inaccessible</td>\n<td>COS authentication required</td>\n<td>Not recommended</td>\n</tr>\n<tr>\n<td>Private read</td>\n<td>Disabled</td>\n<td>Enabled or disabled</td>\n<td>Inaccessible</td>\n<td>COS authentication required</td>\n<td>Unable to use CDN</td>\n</tr>\n</tbody>\n</table>\nConfiguring CDN Acceleration for a Default Accelerated Domain Name\n\nA default accelerated domain name is a CDN accelerated domain name COS automatically assigns to a bucket. The format is `<BucketName-APPID>.file.mycloud.com`. You can enable or disable it as needed.\n\nEnabling the Feature\n\n1. Select a bucket\nLog in to the COS Console, click Bucket List in the left sidebar, and click the bucket to be accelerated to enter the bucket.\n\n2. Enter the configuration page\n\n If you have never used Tencent Cloud CDN service before, please log into the CDN Console and activate the CDN service first.\n\n Click Domain Name Management on the left of the page. The default status is off. Click Edit and toggle it on.\n\n3. Add a CDN service authorization (optional)\n Adding a CDN service authorization is to grant a CDN edge server the service identity which allows it to perform operations on a bucket. Please find the details below.\n\n - Public read bucket: the CDN edge server can access the bucket without any authorization, so there is no need to add a CDN service authorization.\n\nOrigin Server Type: The Default origin server is selected by default. If a static website is enabled for the bucket serving as the origin server and you want to accelerate the static website, you can set the origin server type to Static website origin server. For more information, see CDN Acceleration Overview.\n• Private read bucket: the CDN edge server needs a special service identity to access the bucket. Click **Add a CDN Service Authorization** to grant the CDN edge server the service identity, select **I agree to the authorization above**, and click **OK**.\n\nAfter the authorization is added, the CDN edge server can perform GET Object, Head Object, and Options Object on the bucket.\n\nAfter the authorization is granted, it will be automatically written into the bucket access policy (see below for an example). Then the CDN edge server does not need to do anything else while forwarding traffic to the origin.\n\n```json\n{\n \"Statement\": [\n {\n \"Action\": [\n \"name/cos:GetObject\",\n \"name/cos:HeadObject\",\n \"name/cos:OptionsObject\"\n ],\n \"Effect\": \"allow\",\n \"Principal\": {\n \"qcs\": [\n \"qcs::cam::uin/100000000001:service/cdn\"\n ],\n \"Resource\": [\n \"qcs::cos::ap-chengdu:uid/1250000000:examplebucket-1250000000/*\"\n ]\n }\n }\n ],\n \"version\": \"2.0\"\n}\n```\n\n4. Enable origin-pull authentication (optional)\n\nYou need to add the CDN service authorization before you can enable origin-pull authentication.\n\nOrigin-pull authentication is used to verify the service identity of the CDN edge server so as to prevent unauthorized access. Please find the details below.\nPublic read bucket: the CDN edge server can access the bucket without any authorization, so there is no need to enable origin-pull authentication.\n\nPrivate read bucket: the CDN edge server needs to be verified by origin-pull authentication. Only verified edge server can access the objects in the bucket. To enable the authentication, toggle on **Origin-pull Authentication** and click **Save**.\n\nFor private read buckets, after origin-pull authentication and CDN service authorization are enabled, the CDN edge server will no longer need to carry a signature when accessing the origin server, and the resources cached by CDN will be delivered over the public network. In such case, data security will be under threat. Therefore, it is highly recommended to enable CDN authentication.\n\n5. **Enable CDN acceleration**\n\nAfter clicking **Save**, you will see that the default accelerated domain name is being deployed (which is expected to be completed in about 5 minutes).\n\n**Configuring Authentication**\n\nAfter CDN acceleration is enabled for the default domain name, anyone can access the origin server through this domain name. If your data requires privacy, please be sure to enable the authentication to protect your data on the origin server.\n\nAfter the default accelerated domain name and origin-pull authentication are enabled, a CDN authentication status prompt will appear on the default accelerated domain name management page. You can click **authentication configuration** in the prompt to\nenter the CDN security configuration page for the corresponding domain name.\n\nYou can also go to this page from the CDN Console by clicking Domain Name Management > Management (for the corresponding domain name) > Security Configuration. For detailed configuration directions, see [Authentication Configuration].\n\n**Disabling the Feature**\n\n- On the default accelerated domain name management page, click Edit, toggle the status from on to off, and click Save. The change will be deployed in around 5 minutes. After that, the domain name will be displayed as Deactivated in the CDN Console.\n\n- You can deactivate or delete the domain name in the CDN Console. For more information, see Domain Name Operations.\n\nWhen you delete a domain name in CDN console, you are deleting a CDN acceleration record of the default accelerated domain name, not the domain name itself. You can activate it again in the COS console.\n\n**Configuring CDN Acceleration for a Custom Accelerated Domain Name**\n\nYou can bind a custom domain name with a bucket in the COS Console. After that, you can enable CDN acceleration to speed up access to the bucket through the custom domain name. When binding a custom domain name with a bucket, you need to add a CNAME record to it at your domain name service provider.\n\nCurrently, you need to enable CDN service to use a custom domain name in COS.\n\n1. For domain names connected to a CDN node in Mainland China, you need to complete ICP filing. You are not required to do so through Tencent Cloud though.\n2. For domain names connected to a CDN node outside Mainland China, ICP filing is not required, but please note that your data and operations in Tencent Cloud still need to comply with local laws and regulations as well as Tencent Cloud Service Agreement.\nEnabling the Feature\n\nYou can add a custom domain name and enable CDN acceleration in both COS Console and CDN Console. For more information on how to do so in the CDN Console, see Connect a Domain Name.\n\n1. Select the bucket to be bound with a custom domain name\n\nLog in to the COS Console, click Bucket List in the left sidebar, and click the bucket to be accelerated to enter the bucket.\n\n2. Add a custom domain name\n\nClick Domain Name Management to enter the domain name management page. Click Add a Domain Name in the custom domain name section to start the configuration.\n\nDomain Name: Enter the domain name you have purchased (such as www.example.com).\n\nOrigin Server Type: The Default origin server is selected by default. If a static website is enabled for the selected bucket and you want to accelerate the static website, you can set the origin server type to Static website origin server.\n\n3. Enable origin-pull authentication (optional)\n\nOrigin-pull authentication is used to verify the service identity of the CDN edge server so as to prevent unauthorized access. Please find the details below.\n\n- Public read bucket: the CDN edge server can access the bucket without any authorization, so there is no need to enable origin-pull authentication.\n- Private read bucket: the CDN edge server needs to be authenticated by origin-pull authentication. Only verified edge server can access the objects in the bucket. To enable the authentication, toggle on Origin-pull Authentication.\n\nFor private read buckets, after origin-pull authentication is enabled, the CDN edge server will no longer need to carry a signature when accessing the origin server, and the resources cached by CDN will be delivered over the public network. In such case, data security will be under threat. Therefore, it is highly recommended to enable CDN authentication.\n4. Enable CDN acceleration\n\nClick **Save** on the right. In about 5 minutes, the added custom domain name and CDN acceleration will be deployed.\n\nConfiguring Authentication\n\nAfter CDN acceleration is enabled for the custom domain name, anyone can directly access the origin server through this domain name. If your data requires privacy, please be sure to enable the authentication configuration to protect your data on the origin server.\n\nAfter the custom domain name is deployed, a CDN authentication configuration link will appear in the CDN Authentication column. Click **Settings** to directly enter the CDN Console for CDN authentication configuration. For detailed directions, see [Authentication Configuration].\n\nResolving a Domain Name\n\nAfter the custom domain name is connected to CDN, you will be assigned a CNAME domain name (suffixed with `.cdn.dnsv1.com`). You will need to complete the CNAME configuration through your domain name service provider. For more information, see CNAME Configuration.\n\nYou will not be able to directly access the CNAME domain name.\n\nDisabling the Feature\n\nOn the accelerated custom domain name management page, click **Edit** to change the domain name status from **Enabled** to **Disabled**, click **Save**, and wait for the deployment to be completed in around 5 minutes. After that, the status of the accelerated custom domain name will be **Deactivated** instead of **Activated** in the CDN Console.\n\nYou can only delete a custom domain name when its status is **disabled**. If the status is **enabled**, you will need to change it to **disabled** first.\nYou can deactivate or delete domain names in the CDN Console. For more information, see Domain Name Operations.\n\n<table>\n<thead>\n<tr>\n<th>Domain Management</th>\n<th>Activate CDN</th>\n<th>Deploy to oversea CDN</th>\n<th>More Actions</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Domain</td>\n<td>Status</td>\n<td>CNAME</td>\n<td>Close CDN</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Origin</td>\n<td>Modify project</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Service Type</td>\n<td>Edit Tag</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>COS Origin</td>\n<td>Delete</td>\n</tr>\n<tr>\n<td>ap-singap...</td>\n<td>Activated</td>\n<td>No need to be...</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>COS Origin</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Dynamic content</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nConfiguring GCD\n\nOverview\n\nTencent Cloud Global Content Delivery (GCD) distributes Tencent's high-performance cache nodes globally, which accelerate worldwide static content, content download and delivery, audio/video on-demand services.\n\nTencent Cloud GCD is under open beta test and the quota is limited. Submit an application if you want to have a try. For more information, see How to apply for trial. The following describes how to configure GCD for CDN.\n\nYou need to apply for activating GCD before you can use this feature.\n\nUse Cases\n\n- The end users outside Mainland China need to be reached and accelerating access and reducing access delay are required.\n- Cross-region, cross-border or cross-continent data transfer reaching GB or TB-level is required.\n- The same content needs to be downloaded frequently.\n\nDescription\n\nWhen your application for activating GCD is approved, go to Tencent Cloud’s GCD Console to add COS's XML access domain name for acceleration.\n\nYou need to set the content to be accessed to Public in COS in order to bind and use the GCD accelerated domain name to access the content on COS.\n\nDirections\n\nConfigure GCD by following the steps below: Configure Policy Permissions -> Configure GCD -> Configure CNAME.\n\nConfigure policy permissions\n\n1. Log in to Tencent Cloud's COS Console to go to the management page. Click the Permission Management tab to add a public access policy.\n2. Click **Add Policy**, and then set **User**, **Resource** and **Operation** as follows:\n\n- **Effect**: Allow\n- **User**: All Users\n- **Resource**: Entire Bucket\nOperation: Read Access\n\nConfigure GCD\n\n1. Obtain the COS domain name.\n In the COS Console, obtain the access domain name of the bucket for which you want to accelerate access.\n \n examplebucket-1250000000.cos.ap-guangzhou.myqcloud.com\n\n If you want to accelerate the delivery of content for a bucket for which the static website feature is enabled, and use the features of a static website, use a static website domain name, for example:\n\n examplebucket-1250000000.cos-website.ap-guangzhou.myqcloud.com\n\n2. Bind a domain name to GCD\n Log in to Tencent Cloud's GCD Console, and then add a domain name by using COS as your self-owned origin. The configuration items are as follows:\n \n - Domain: Enter the access domain name you want to bind to GCD.\n - Service Type: The data in COS is mostly unstructured data. It is recommended to select Static Content.\n - Origin Type: Select External (self-owned origin).\n- Origin Domain: Enter COS's XML API domain name or static website domain name.\n- Host header (origin-pull Host): This should be same as the origin server's domain name.\n\nCreate a Distribution\n\n| Domain | yourdomain.com |\n| Service Type | Static content |\n| Project | Default |\n| Origin type | External | Object storage (COS) |\n| Origin IP/domain | examplebucket-125.cos.ap-guangzhou.myqcloud.com |\n| Host header | examplebucket-125.cos.ap-guangzhou.myqcloud.com |\n\nSet other options as needed. For more information, see Getting Started in GCD documentation.\n\nConfigure CNAME\n\nGo to your DNS service provider to add the CNAME record. For more information on how to configure CNAME, see CNAME Configuration in CDN documentation.\n\nFAQs\n\nFor the question whether a domain name that has not gone through filing procedure with MIIT can be bound to GCD and other questions, see FAQs in COS documentation.\nSingle link speed limit\n\nCOS supports traffic throttling when uploading and downloading files to ensure the network bandwidth of your other applications. You can use the **PutObject**、**PostObject**、**GetObject**、**UploadPart** The x-cos-traffic-limit parameter is used when the request is made, and the speed limit value is set. COS will control the network bandwidth of this request according to the speed limit value set.\n\nInstructions\n\n- Users use the x-cos-traffic-limit parameter to specify the speed limit for this request when requesting Object, PostObject, GetObject and UploadPart. This parameter can be set to header, request parameters, or in the form field when using the form upload API.\n- The value of the x-cos-traffic-limit parameter must be numeric and the unit defaults to bit/s.\n- The speed limit is set in the range of 819200-838860800, that is, 100KB/s-100MB picks. If it is beyond this range, a 400th error will be returned.\n\nAPI Use Case\n\nThe following is an example of a simple upload API. The speed limit is 1048576 bit/s, that is, 128KB API:\n\n```plaintext\nPUT /exampleobject HTTP/1.1\nHost: examplebucket-1250000000.cos.ap-beijing.myqcloud.com\nContent-Length: 13\nAuthorization: q-sign-algorithm=sha1&q-ak=AKID8A0fBVtYFrNm02oY1g1JQQF0c3J0****&q-sign-time=1561109068;1561116268&q-key-time=1561109068;1561116268&q-header-list=content-length;content-md5;content-type;date;host&q-url-param-list=&q-signature=998bfc8836fc285d99e455c14e3e623ed2****\nx-cos-traffic-limit: 1048576\n```\nBatch Processing Overview\n\nLast updated: 2020-01-15 16:32:19\n\nThe batch operation feature of COS allows you to perform specified operations on the specified object list in the bucket. You can generate an inventory of objects through the inventory feature as the specified object list, or record the objects to be processed in a CSV file according to the format requirement of an inventory file. Then, COS will process the objects in batches based on the object inventory file.\n\nFor more information, please see Inventory Overview.\n\nAt present, the batch operation feature only supports the following operation:\n\n- **Replicating Objects in Batches**\n\nYou can use the batch operation feature in the COS Console. For more information, please see Batch Operation.\n\nHow It Works\n\nTo perform a batch operation, you need to create a batch operation job first, which contains all the information needed to perform the specified operation on the object list. You can use an inventory as an object list.\n\nAfter you provide an object file and start the created batch operation job, the batch operation feature will execute the specified operation on the objects in the inventory sequentially. During job execution, you can monitor the execution status in the COS Console or choose to output a job report after the job is completed. The job report details the status of every operation in the job.\n\nThe batch operation feature is only applicable to objects in the current bucket. If you want to batch operate on the objects in another bucket, please enable the batch operation feature for that bucket.\n\nObject Inventory\n\nAn object inventory is a list of all the objects to be operated on. To create a batch operation job, you need to provide an object inventory first to tell COS what objects it should operate on. You need to put the object inventory file in the bucket and provide such information as the file name, ETag, and VersionID (if applicable). You can create an object inventory in the following two ways:\n\n- **COS inventory feature.** This feature outputs an object inventory in CSV format. For more information, please see Inventory Overview. If your object inventory contains version ID information, COS will batch operate on the objects with the corresponding version ID.\n\n- **CSV file configuration:** Every row in the CSV file must contain the bucket name and the name and version ID (optional) of an object for batch operation. If versioning has never been enabled, you can ignore the object version ID information. The CSV file can be configured as shown below:\n\n```plaintext\nexamplebucket-appid, exampleobject, PZibn9D51P6p298B7S9_cexlIn5EJ0p\nexamplebucket-appid, exampleobject, PZibn9D51P6p298B7S9_cexlIn5EJ0p\nexamplebucket-appid, exampleobject, jbo@jhdPxyB4Rrm0xWS0kU8EoNrlU_0I\n```\n\n- If versioning is or was once enabled for your bucket, you must provide object versioning information in the object inventory. Before executing a job, COS will parse your inventory and determine the objects to be operated on based on the inventory.\nAn object inventory can contain all the objects in a bucket. However, it may take a longer time to operate on a large number of objects.\n\nIf version ID is not specified, COS will operate on the objects on the latest version by default. If you uploaded an object file with the same name as an object to be operated on before creating a job, COS will operate on the object on the latest version by default rather than the version when the object inventory was created. To avoid this issue, you can enable versioning and specify the version ID in the object inventory.\n\n**Batch Operation Job**\n\nThis section describes how to create a batch operation job and how the system will respond after creation.\n\nWhen creating a batch operation job, you need to provide the following information:\n\n- **Operation**\n You need to specify which operation is to be performed on the objects. The corresponding parameters can be configured for each operation, and COS will perform the operation on the objects in the inventory sequentially according to the configuration.\n\n- **Object inventory**\n An object inventory is a list of all the objects to be operated. You can create an object inventory through the inventory feature. For more information, please see [Inventory Overview](#). You can also record the objects to be processed in a CSV file according to the format requirement of an inventory file.\n\n- **Priority**\n You can set priority to identify the precedence of the current batch operation job over other jobs. Job priority does not directly determine the order in which the jobs will be completed. If you want to control the order of multiple jobs, you need to check the job execution status on your own and start the next job after the current one is completed.\n\n- **Rule permission**\n After creating a batch operation job, you need to make sure that your account has the corresponding IAM permission to perform the operation. For example, if you have created a batch operation job to execute `PUT Object-copy`, you should make sure that your account has the `Get Object` permission in the source bucket and the `PUT Object` permission in the destination bucket. In addition, for all batch operation jobs, you should have permission to read the object inventory and write into the job report. For more information on permission configuration, please see [Access Policy Language Overview](#) and [Examples of Bucket Policies](#).\n\n- **Job report**\n If you want to output a job report after a batch operation job is completed, you need to enter the corresponding parameters when creating the job, so that the system can correctly output the job report to the specified destination bucket. The required information includes the bucket to store the job report, job report format, and whether all job information should be included, while the file prefix of the job report is optional.\n\n- **Job description (optional)**\n You can provide 256 bytes of job description for your created batch operation job to help track and monitor job execution. The detailed information of the job description will be displayed in your COS Console. You can sort or filter your jobs conveniently by job description. The same job description can be configured for similar jobs (e.g., syncing log data on a weekly basis) to manage them in a centralized manner.\nThe batch replication feature is used to replicate objects in the inventory, i.e., allowing you to batch replicate the specified objects from the source bucket to the destination bucket in the same region or in different regions. It supports customizing parameters for the **PUT Object-copy** operation, and the copy metadata and storage type are subject to the configuration information. For more information, please see **PUT Object-copy**.\n\n### Use Limits\n\n- All objects to be replicated must be in the same bucket.\n- Only one destination bucket can be configured for a batch replication job.\n- You need to have permission to read objects from the source bucket and write objects into the destination bucket.\n- The total size of the objects cannot exceed 5 GB.\n- Verification via ETags and server-side encryption using custom keys are not supported.\n- If the destination bucket does not have versioning enabled and contains an object file with the same name as a file to be replicated, COS will overwrite the object file.\nBatch Resume archive object\n\nBatch restoring archived objects can be used to restore objects of archived storage type in the inventory. This operation supports customizing parameters related to POST Object restore. These configuration information will affect the restoration and expiration time of the replica. For more information on POST Object restore, see POST Object restore.\n\nTo create a job for batch restoring archived objects, you need to specify the following two parameters:\n\n- **Restoration mode**: Standard or batch mode. For more information on restoration mode, see Restoring Archived Objects.\n- **Replica validity period**: When an object of archived type is restored, a temporary replica is created, which will expire and be deleted automatically after a specified time period. For more information on the validity period of a replica, see Restoring Archive Objects.\n\n**Notes**\n\nIf the job to batch restore archived objects includes replicas of objects that have already been restored, the validity period of these objects will be updated when the job starts, ensuring that all object replicas in the job have the same validity period.\nManaging Batch Operation Jobs\n\nThis document describes how to manage batch operation jobs in the COS Console.\n\nFiltering Jobs\n\nYou can view the list of the batch operation jobs created in the last 90 days using the List Jobs API. The list contains information of each job, such as job ID, description, priority, status, and execution progress. You can filter them by job status in the list to display the ones in the same status or filter them by job description or ID in the console.\n\nQuerying Job Status\n\nIf you need more information, you can get all the information of a job using the DescribeJob API. This API will return such information as the operation configuration of the specified job, object inventory information, and job report.\n\nSetting Job Priority\n\nYou can set priority for your batch operation jobs, and COS will execute them based on priority, i.e., executing jobs of a higher priority first. Priority is expressed as an integer; the greater the value, the higher the priority. You can modify the priority during job execution. If a higher-priority job needs to be added, you can run it first by pausing the lower-priority job.\n\nAlthough higher-priority jobs generally take precedence over lower-priority ones, priority is not a criterion for sequential execution. If you want to run batch operation jobs sequentially, please monitor the execution status of each job on your own and start them manually.\n\nJob Status\nJob status changes as the execution proceeds, as shown below:\n\n<table>\n<thead>\n<tr>\n<th>Job Status</th>\n<th>Description</th>\n<th>Next Status</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>New</td>\n<td>When a job is created, its status will be "New".</td>\n<td>It can change to "Preparing", meaning that COS starts to parse the inventory in the job.</td>\n</tr>\n<tr>\n<td>Preparing</td>\n<td>When COS starts to parse the configured inventory in the batch operation job, the job status will change to "Preparing".</td>\n<td>It can change to "Ready" or "Suspended". The former means that COS has finished parsing the job configuration information and is going to perform the specified operation on the objects in the inventory based on the configuration, while the latter means that COS has finished parsing the job configuration information but is still waiting for your confirmation before it proceeds to perform the specified operation (this status appears if a batch operation job is configured in the console).</td>\n</tr>\n<tr>\n<td>Suspended</td>\n<td>A batch operation job pending your confirmation is in the "Suspended" status, which appears if the job is created in the console. After your confirmation, COS will start executing the job, and the status will change accordingly and cannot revert to "Suspended".</td>\n<td>When you confirm to execute the job, the job status will change to "Ready".</td>\n</tr>\n<tr>\n<td>Ready</td>\n<td>When COS has finished parsing the object inventory and job configuration information in your batch operation job and is going to perform the operation, the job status will change to "Ready".</td>\n<td>It can change to "Active", at which point COS starts executing the job. If a higher-priority job is running, COS will keep the job status as "Ready" until the job status of the higher-priority job changes to "Complete".</td>\n</tr>\n<tr>\n<td>Job Status</td>\n<td>Description</td>\n<td>Next Status</td>\n</tr>\n<tr>\n<td>------------</td>\n<td>-------------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>Active</td>\n<td>When COS is performing an operation on the objects in the inventory based on the configuration information, the job status will be "Active". You can query job progress in the console or by calling the DescribeJob API.</td>\n<td>It can change to "Complete", "Failing", "Pausing", or "Cancelling" if your job succeeds, fails, or is paused or canceled.</td>\n</tr>\n<tr>\n<td>Pausing</td>\n<td>After COS pauses an ongoing job and before the status changes to "Paused", the job status in between will be "Pausing".</td>\n<td>It can be followed by "Paused" when COS has successfully paused the ongoing job.</td>\n</tr>\n<tr>\n<td>Paused</td>\n<td>If a higher-priority job is created, the status of the ongoing job will change to "Paused".</td>\n<td>If the higher-priority job is completed, fails, or is pending conformation, the job in "Paused" status can automatically shift to "Active" status.</td>\n</tr>\n<tr>\n<td>Complete</td>\n<td>When the batch operation job has successfully completed the operation on all the objects in the inventory or fails, the job status will change to "Complete". If job report generation is configured, COS will deliver the report to your specified bucket when the status changes to "Complete".</td>\n<td>"Complete" is a final status, i.e., the job will not change to any other status.</td>\n</tr>\n<tr>\n<td>Cancelling</td>\n<td>After COS cancels an ongoing job and before the status changes to "Cancelled", the job status in between will be "Cancelling".</td>\n<td>It can be followed by "Cancelled" when COS has successfully canceled the ongoing job.</td>\n</tr>\n<tr>\n<td>Cancelled</td>\n<td>When a batch operation job is successfully canceled, the job status will change to "Cancelled". At this point, you cannot make any modification to the job status.</td>\n<td>"Cancelled" is a final status, i.e., the job will not change to any other status.</td>\n</tr>\n<tr>\n<td>Failing</td>\n<td>The "Failing" status comes before "Failed".</td>\n<td>It can change to the "Failed" status.</td>\n</tr>\n<tr>\n<td>Failed</td>\n<td>After a job fails, the job status will change to "Failed". For more information, please see Tracking a Failing Job.</td>\n<td>"Failed" is a final status, i.e., the job will not change to any other status.</td>\n</tr>\n</tbody>\n</table>\n\n### Tracking a Failing Job\n\nIf a problem arises during job execution, such as trouble in parsing the object inventory, the batch operation job will fail, and COS will return the corresponding error code and cause. You can call the DescribeJob API or view the job report to get the cause of failure and other information.\n\nCOS sets an operation failure threshold for each batch operation job to avoid frequent operation failures. If a job involves more than 1,000 operations, COS will monitor the operation failure rate, i.e., ratio of failing operations to all operations executed. If the rate exceeds the threshold of 50% at any moment, COS will terminate the job and return the failure message. You can check the cause why this happens (e.g., the object inventory contains large amounts of information on non-existing objects). Then, you can fix the problem accordingly and create a job again.\nCOS executes batch operation jobs in an async manner and does not necessarily perform operations in the same order as that of objects in the inventory. Therefore, you cannot determine which object is being operated on according to the order in the object inventory and whether an operation is successful or fails. However, you can get the information on successful or failing operations from the job report.\n\nJob Report\n\nYou can configure whether to output a job report when creating a job. If yes, COS will output a job report when the job succeeds, failure, or is canceled. You can view the information on all successful or failing operations in the job report.\n\nA job report contains such information as the configuration parameters and execution status of the specified operation as well as name and version ID of the objects operated on, operation status codes, and error description.\nMonitoring and Alarming\n\nOverview\n\nCOS statistics such as read and write requests and traffic are collected and displayed by Cloud Monitor. You can view detailed monitoring data in the Cloud Monitor Console.\n\nThis document describes how to get statistics in the COS Console. For more information on how to use Cloud Monitor APIs to get more detailed data, see Cloud Monitoring product documentation.\n\nBasic Features\n\nCloud Monitor provides the following entries for COS to implement monitoring and alarming.\n\n<table>\n<thead>\n<tr>\n<th>Module</th>\n<th>Capabilities</th>\n<th>Main Features</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Monitoring overview</td>\n<td>Displays the current status of the product</td>\n<td>Provides general overview, alarm overview, and overall monitoring information</td>\n</tr>\n<tr>\n<td>Alarm management</td>\n<td>Supports alarm management and configuration</td>\n<td>Supports creating new COS alarming policies, custom messages, and trigger templates</td>\n</tr>\n<tr>\n<td>Monitoring platform</td>\n<td>Monitors traffic and displays data of user-defined monitoring metrics</td>\n<td>Displays your overall bandwidth information and allows you to customize monitoring metrics and data to be reported</td>\n</tr>\n<tr>\n<td>Cloud product monitoring</td>\n<td>Displays the COS bucket monitoring view</td>\n<td>Allows you to query the current monitoring views and data such as read and write requests and traffic for each bucket</td>\n</tr>\n</tbody>\n</table>\n\nUse Cases\n\n- **Daily management**: you can log in to the Cloud Monitor Console to view the running status of COS in real time.\n- **Troubleshooting**: you will receive alarm notifications when a monitoring metric reaches the alarming threshold, allowing you to quickly get notifications for exceptions, check the causes, and fix them in a timely manner.\n\nViewing in the Console\n\nYou can log in to the Cloud Monitor Console to view the monitoring data for COS.\n\nCalling APIs\n\nYou can view the monitoring data for COS by calling the corresponding APIs. Below are the monitoring metrics for COS.\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n<th>Unit</th>\n</tr>\n</thead>\n</table>\n## Cloud Object Storage\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n<th>Unit</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>std_storage</td>\n<td>Standard storage - storage capacity</td>\n<td>MB</td>\n</tr>\n<tr>\n<td>sia_storage</td>\n<td>Standard_IA storage - storage capacity</td>\n<td>MB</td>\n</tr>\n<tr>\n<td>nel_storage</td>\n<td>Nearline Storage - storage capacity</td>\n<td>MB</td>\n</tr>\n<tr>\n<td>arc_storage</td>\n<td>Archive storage - storage capacity</td>\n<td>MB</td>\n</tr>\n</tbody>\n</table>\n\n## Traffic\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n<th>Unit</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>internet_traffic</td>\n<td>Public network traffic</td>\n<td>B</td>\n</tr>\n<tr>\n<td>internal_traffic</td>\n<td>Private network traffic</td>\n<td>B</td>\n</tr>\n<tr>\n<td>cdn_origin_traffic</td>\n<td>CDN origin-pull traffic</td>\n<td>B</td>\n</tr>\n<tr>\n<td>inbound_traffic</td>\n<td>Upload traffic</td>\n<td>B</td>\n</tr>\n</tbody>\n</table>\n\n## Data Retrieval\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n<th>Unit</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>std_retrieval</td>\n<td>Standard data retrieval</td>\n<td>B</td>\n</tr>\n<tr>\n<td>sia_retrieval</td>\n<td>Standard_IA data retrieval</td>\n<td>B</td>\n</tr>\n<tr>\n<td>nel_retrieval</td>\n<td>Nearline data retrieval</td>\n<td>B</td>\n</tr>\n</tbody>\n</table>\n\n## Requests\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n<th>Unit</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>std_read_requests</td>\n<td>Standard storage read requests</td>\n<td>/</td>\n</tr>\n<tr>\n<td>std_write_requests</td>\n<td>Standard storage write requests</td>\n<td>/</td>\n</tr>\n<tr>\n<td>ia_read_requests</td>\n<td>Standard_IA storage read requests</td>\n<td>/</td>\n</tr>\n<tr>\n<td>ia_write_requests</td>\n<td>Standard_IA storage write requests</td>\n<td>/</td>\n</tr>\n<tr>\n<td>nl_read_requests</td>\n<td>Nearline storage read requests</td>\n<td>/</td>\n</tr>\n<tr>\n<td>nl_write_requests</td>\n<td>Nearline storage write requests</td>\n<td>/</td>\n</tr>\n</tbody>\n</table>\n\n## Return Codes\n\n<table>\n<thead>\n<tr>\n<th>Metric Name</th>\n<th>Description</th>\n<th>Unit</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2xx_response</td>\n<td>2xx status codes</td>\n<td>/</td>\n</tr>\n<tr>\n<td>3xx_response</td>\n<td>3xx status codes</td>\n<td>/</td>\n</tr>\n<tr>\n<td>4xx_response</td>\n<td>4xx status codes</td>\n<td>/</td>\n</tr>\n<tr>\n<td>5xx_response</td>\n<td>5xx status codes</td>\n<td>/</td>\n</tr>\n</tbody>\n</table>\nMonitoring Descriptions\n\n- **Monitoring interval**: Cloud Monitor supports multiple types of monitoring intervals, including monitoring data in real time, in the past 24 hours, in the past 7 days, and in user-specified period, with time granularity of 1 minute or 5 minutes.\n\n- **Data retention**: monitoring data with 1-minute, 5-minute, and 1-hour granularity will be retained for 31 days; monitoring data with 1-day granularity will be retained for half a year.\n\n- **Alarm display**: Cloud Monitor integrates the monitoring data of COS and displays the data entries in intuitive graphs, making it easier for you to stay informed of the overall status.\n\n- **Alarm setting**: you can set alarm-triggering thresholds for the metrics. Cloud Monitor will send notifications to specified recipients when the alarm is triggered. For more information, see [https://intl.cloud.tencent.com/doc/product/248/6126).](https://intl.cloud.tencent.com/doc/product/248/6126)\nGlobal Acceleration Overview\n\nThe global acceleration feature of Tencent Cloud COS utilizes a load balancing system based on Tencent's global traffic scheduling to intelligently route and parse user requests and select the optimal network linkage for nearby access. Backed by globally deployed Tencent Cloud data centers, it allows users across the world to quickly access your buckets and improves your business access success rate for a higher business stability and smoother user experience.\n\nDirections\n\nYou can enable global acceleration in the COS Console or through APIs.\n\nVia the COS Console\n\nYou can enable global acceleration for your buckets in the COS Console. For more information, please see Enabling Global Acceleration in console documentation.\n\nVia REST API\n\nYou can directly use the following APIs to enable global acceleration:\n\n- PUT Bucket Accelerate\n- GET Bucket Accelerate\n\nAccess domain name\n\nAfter enabling global acceleration, you can access your COS files through two types of domain names:\n\n- **Default bucket domain name**: The format is `<BucketName-APPID>.cos.<Region>.myqcloud.com`. For more information, please see Regions and Access Domain Names.\n- **Global acceleration domain name**: The format is `<BucketName-APPID>.cos.accelerate.myqcloud.com`.\n\nTake the bucket `examplebucket-125000000` in Guangzhou as an example. If you have enabled global acceleration for it, when you need to upload the file `exampleObject.txt` from Beijing to it, you can do so in the following two ways:\n\n- **Use the global acceleration domain name for access**: When uploading the object, you need to set the domain name to `exampleBucket-125000000.cos.accelerate.myqcloud.com`. When you upload the object through this domain name, COS will intelligently parse your request based on your network conditions and implement nearby access. For example, it will forward your request to the Beijing access layer and then transmit it to the Guangzhou storage layer via a private network Direct Connect line to accelerate data transfer.\n\n- **Use the default bucket domain name for access**: When uploading the object, you need to set the domain name to `examplebucket-125000000.cos.ap-guangzhou.myqcloud.com`. When you upload the object through this domain name, your request will be directly forwarded to the Guangzhou access layer and then the Guangzhou storage layer. In this case, long public network linkage may lead to unstable transfer.\nIf you use global acceleration, fees will be incurred. Therefore, it is recommended that you carefully evaluate this feature based on your actual business needs:\n\n1. If your business has more writes (e.g., PUT Object, POST Object, and Multipart Upload) than reads and uploads data from a remote region to Tencent Cloud data centers, you are recommended to use a global acceleration domain name.\n2. If your business has more reads (e.g., GET Object) than writes and mainly involves file download, you are recommended to perform a comprehensive evaluation on the **CDN-based access acceleration** solution and select the option with the best cost performance.\n3. If your business mainly involves configuration operations or file extraction, you are recommended to use a default bucket domain name.\n4. If your business needs to access buckets over the private network or a direct connect line in the same region, you are recommended to use a default bucket domain name.\n\nNotes\n\nBelow are precautions for using a global acceleration domain name:\n\n- The global acceleration domain name will take effect in 15 minutes after being enabled. Please wait patiently.\n- After the global acceleration domain name is enabled, the maximum bandwidth for a bucket through it will be allocated based on the business volume on the entire network.\n- After the global acceleration domain name is enabled, only requests with it will be accelerated. However, the default bucket domain name can still be used.\n- When the global acceleration domain name is used, fees will be incurred only for the accelerated linkage of requests. For example, if you use the global acceleration domain name to upload data from Beijing to a bucket in Beijing, as the linkage is not accelerated, the request will not incur acceleration fees.\n- When using the global acceleration domain name, you can specify the HTTP or HTTPS transfer protocol. If the request is transmitted via a private network Direct Connect line, COS will choose to use the HTTPS protocol to guarantee data transfer security as appropriate."}}},{"rowIdx":83,"cells":{"id":{"kind":"string","value":"255532ece3237be85bfb6ef9c04c0411dc9f9eba"},"text":{"kind":"string","value":"1999\n\n**Embed[ed]ed Zerotree Codec**\n\nKarma Wangdi \n*Edith Cowan University*\n\n---\n\n**Follow this and additional works at:** [https://ro.ecu.edu.au/theses_hons](https://ro.ecu.edu.au/theses_hons)\n\n**Part of the Software Engineering Commons**\n\n**Recommended Citation** \n\n---\n\nThis Thesis is posted at Research Online. \nEdith Cowan University\n\nCopyright Warning\n\nYou may print or download ONE copy of this document for the purpose of your own research or study.\n\nThe University does not authorize you to copy, communicate or otherwise make available electronically to any other person any copyright material contained on this site.\n\nYou are reminded of the following:\n\n- Copyright owners are entitled to take legal action against persons who infringe their copyright.\n- A reproduction of material that is protected by copyright may be a copyright infringement.\n- A court may impose penalties and award damages in relation to offences and infringements relating to copyright material. Higher penalties may apply, and higher damages may be awarded, for offences and infringements involving the conversion of material into digital or electronic form.\nI certify that this thesis does not incorporate without acknowledgment any material previously submitted for a degree or diploma in any institution of higher education and that to the best of my knowledge and belief does not contain any material previously published or written by another person except where due reference has been made in the text.\nUSE OF THESIS\n\nThe Use of Thesis statement is not included in this version of the thesis.\nEmbedded Zerotree Codec\n\nA Thesis Submitted in Partial Fulfilment of the Requirements for the Award of Bachelor of Engineering (Electronic Systems) with First Class Honours\n\nKarma Wangdi\n\nFaculty of Communications, Health and Science\nEdith Cowan University\nWestern Australia\n\nDate of submission: 9 November 1999\nTABLE OF CONTENTS\n\nACKNOWLEDGEMENT ............................................................................................................................. 4\n\nABSTRACT ................................................................................................................................................... 5\n\nINTRODUCTION ......................................................................................................................................... 6\n\nPROJECT DEFINITION ............................................................................................................................. 8\n\nAIM .............................................................................................................................................................. 8\nSCOPE ....................................................................................................................................................... 8\n\n1. INTRODUCTION TO IMAGE COMPRESSION .................................................................................. 10\n\n1.1 INTRODUCTION ................................................................................................................................ 10\n\n1.2 BASIS OF IMAGE COMPRESSION ............................................................................................ 10\n\n1.2.1 Data Redundancy ..................................................................................................................... 10\n\n1.2.1.a Coding Redundancy ............................................................................................................ 10\n\n1.2.1.b Interpixel Redundancy ....................................................................................................... 11\n\n1.2.1.c Psychovisual Redundancy .................................................................................................. 11\n\n1.2.2 Data Irrelevancy ..................................................................................................................... 12\n\n1.3 IMAGE COMPRESSION MODELS ............................................................................................. 12\n\n1.3.1 The Source Encoder and Decoder ......................................................................................... 13\n\n1.4 TYPES OF IMAGE COMPRESSION TECHNIQUES ........................................................................ 15\n\n1.4.1 Lossless Compression Techniques ........................................................................................ 17\n\n1.4.1.a Bit Plane Encoding ............................................................................................................ 17\n\n1.4.1.b Lossless Predictive Coding ................................................................................................ 18\n\n1.4.2 Lossy Compression Techniques ........................................................................................... 19\n\n1.4.2.a Discrete Cosine Transform Coding ...................................................................................... 19\n\n1.4.2.b Vector Quantization ........................................................................................................... 20\n\n1.4.2.c Wavelet Coding ................................................................................................................ 21\n\n1.4.2.d Lossy Plus Lossless Residual Coding .............................................................................. 21\n\n2. WAVELET TRANSFORM AND IMAGE COMPRESSION ................................................................. 23\n\n2.1 INTRODUCTION ............................................................................................................................ 23\n\n2.2 MATHEMATICAL REPRESENTATION OF WAVELETS ............................................................ 23\n\n2.3 CONTINUOUS WAVELET TRANSFORM .................................................................................. 25\n\n2.3.1 Resolution from Continuous Wavelet Transform ................................................................ 27\n\n2.4 DISCRETE WAVELET TRANSFORM ......................................................................................... 28\n\n2.4.1 Resolution from Discrete Wavelet Transform ..................................................................... 29\n\n2.5 WAVELET TRANSFORM AND DIGITAL IMAGE COMPRESSION ........................................... 30\n\n2.5.1 Data Compression ................................................................................................................ 30\n\n2.5.2 Better Frequency Resolution .............................................................................................. 31\n\n2.5.3 Noise Immunity .................................................................................................................... 32\n\n3. THE EZW ALGORITHM .................................................................................................................... 33\n\n3.1 INTRODUCTION ............................................................................................................................ 33\n\n3.2 FEATURES OF THE EMBEDDED CODER .............................................................................. 33\n\n3.3 2-D DISCRETE WAVELET TRANSFORM OF IMAGE ................................................................. 34\n\n3.4 THE ZEROTREE DATA STRUCTURE ......................................................................................... 35\n\n3.5 THE NUMBER OF ZEROTREES ................................................................................................. 36\n\n3.6 THE SIGNIFICANCE MAP .......................................................................................................... 38\n\n3.7 SCANNING OF COEFFICIENTS ............................................................................................... 38\n\n3.8 ENCODING A WAVELET COEFFICIENT .................................................................................. 38\n\n3.9 SUCCESSIVE APPROXIMATION QUANTIZATION .................................................................. 40\n\n3.10 EXPERIMENTAL RESULTS OBTAINED BY SHAPIRO .......................................................... 41\n\nKarma Wangdi\nFIGURES AND TABLES\n\nList of Figures\n\n<table>\n<thead>\n<tr>\n<th>Fig No</th>\n<th>Figure Name</th>\n<th>Page No</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1.1</td>\n<td>The Operational space of Compression Algorithm Design</td>\n<td>13</td>\n</tr>\n<tr>\n<td>1.2</td>\n<td>A General Image Compression System Model</td>\n<td>13</td>\n</tr>\n<tr>\n<td>1.3</td>\n<td>Source Encoder and Source Decoder Model</td>\n<td>14</td>\n</tr>\n<tr>\n<td>1.4</td>\n<td>Image Compression Techniques</td>\n<td>16</td>\n</tr>\n<tr>\n<td>1.5</td>\n<td>A General Compression Framework</td>\n<td>17</td>\n</tr>\n<tr>\n<td>1.6</td>\n<td>An image whose pixel values are k bits wide decomposed into k–bit planes</td>\n<td>18</td>\n</tr>\n<tr>\n<td>1.7</td>\n<td>A Lossless Predictive Coding Model</td>\n<td>19</td>\n</tr>\n<tr>\n<td>1.8</td>\n<td>8 x 8 DCT Basis Function</td>\n<td>20</td>\n</tr>\n<tr>\n<td>1.9</td>\n<td>Vector Quantization Block Diagram</td>\n<td>21</td>\n</tr>\n<tr>\n<td>2.1</td>\n<td>Wavelet Transform as passing a signal through sets of High pass and Low pass filters</td>\n<td>27</td>\n</tr>\n<tr>\n<td>2.2</td>\n<td>Time and Frequency Resolution from Continuous Wavelet Transform</td>\n<td>28</td>\n</tr>\n<tr>\n<td>2.3</td>\n<td>Discrete Wavelet Transform</td>\n<td>30</td>\n</tr>\n<tr>\n<td>2.4</td>\n<td>Time-Frequency Resolution from Discrete Wavelet Transform</td>\n<td>31</td>\n</tr>\n<tr>\n<td>2.5</td>\n<td>Data Reduction in DWT</td>\n<td>32</td>\n</tr>\n<tr>\n<td>2.6</td>\n<td>The Original (noisy) and transformed sine curves</td>\n<td>33</td>\n</tr>\n<tr>\n<td>2.7</td>\n<td>The Reconstructed low noise signal</td>\n<td>33</td>\n</tr>\n<tr>\n<td>3.0</td>\n<td>A Generic Transform Coder</td>\n<td>35</td>\n</tr>\n<tr>\n<td>3.1</td>\n<td>A one-scale 2-D Wavelet Decomposition of an Image</td>\n<td>35</td>\n</tr>\n<tr>\n<td>3.2</td>\n<td>A three-scale 2-D Wavelet Decomposition of an Image</td>\n<td>35</td>\n</tr>\n<tr>\n<td>3.3</td>\n<td>Parent-Child relationship of a three scale 2-D wavelet coefficients</td>\n<td>37</td>\n</tr>\n<tr>\n<td>3.4</td>\n<td>A three-scale decomposition of 8x8 wavelet coefficients</td>\n<td>38</td>\n</tr>\n<tr>\n<td>3.5</td>\n<td>A 2 scale decomposition for an 8x8 wavelet coefficients</td>\n<td>38</td>\n</tr>\n<tr>\n<td>3.6</td>\n<td>A tree structure of wavelet coefficients</td>\n<td>38</td>\n</tr>\n<tr>\n<td>3.7</td>\n<td>Scanning order of the Subbands for Encoding a Significance Map</td>\n<td>39</td>\n</tr>\n<tr>\n<td>3.8</td>\n<td>Flow Chart for Encoding a Coefficient of the Significance Map</td>\n<td>40</td>\n</tr>\n<tr>\n<td>4.1</td>\n<td>The Encoder</td>\n<td>44</td>\n</tr>\n<tr>\n<td>4.2</td>\n<td>One to one mapping of the coefficients in a tree to a memory bank</td>\n<td>45</td>\n</tr>\n<tr>\n<td>4.3</td>\n<td>The Memory bank with the four Fields</td>\n<td>46</td>\n</tr>\n<tr>\n<td>4.4</td>\n<td>Encoding Coefficients of memory bank for threshold T</td>\n<td>48</td>\n</tr>\n<tr>\n<td>4.5</td>\n<td>Significance Map Generation of the memory bank; showing direction of processing</td>\n<td>48</td>\n</tr>\n<tr>\n<td>4.5.1</td>\n<td>Flow chart to determine the DSig field of a parent coefficient</td>\n<td>51</td>\n</tr>\n<tr>\n<td>4.6</td>\n<td>Assignment of codes; showing direction of processing</td>\n<td>52</td>\n</tr>\n<tr>\n<td>4.7</td>\n<td>Coefficients and their reconstructed values form knowing the threshold</td>\n<td>56</td>\n</tr>\n<tr>\n<td>4.8</td>\n<td>The two dimensional array for storing information on the coefficients</td>\n<td>56</td>\n</tr>\n<tr>\n<td>4.9</td>\n<td>The two dimensional array with information for the first significant coefficient</td>\n<td>57</td>\n</tr>\n<tr>\n<td>4.10</td>\n<td>The two dimensional array with information for the first three significant codes</td>\n<td>58</td>\n</tr>\n</tbody>\n</table>\n4.11 The output code array after three significant code coding from the Example\n\n4.12 Array for record fields used for decoding\n\n4.13 Diagrammatic Representation of the Decoder\n\n4.13.1 Flow Chart for checking the Decoded and ZTF fields before reading the code from the code container\n\n4.13.2 Flow chart for deciphering the code and reconstructing the coefficients\n\n4.14 The three main branches of a tree\n\n4.15 Mapping of the coefficients of three branches into 3 memory banks\n\n4.16 The three encoders and the DSig Processor\n\n4.17 Single processor codec\n\n4.18 The Parallel Architecture codec\n\n5.1 Shapiro's data for the single processor codec\n\n5.2 I level schematic of significance map generator\n\n5.3 II level schematic of significance map generator\n\n5.4 Gate level schematic of the whole significance map generator\n\n5.5 Magnified part of the significance map generator\n\nList of Tables\n\n<table>\n<thead>\n<tr>\n<th>Table No</th>\n<th>Table</th>\n<th>Page no</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>3.1</td>\n<td>Symbols and their meanings for coding a wavelet coefficient</td>\n<td>40</td>\n</tr>\n<tr>\n<td>5.1</td>\n<td>Reconstructed coefficients from first 21 codes</td>\n<td>79</td>\n</tr>\n<tr>\n<td>5.2</td>\n<td>Reconstructed coefficients from first 44 codes</td>\n<td>79</td>\n</tr>\n<tr>\n<td>5.3</td>\n<td>Reconstructed coefficients from first 100 codes</td>\n<td>79</td>\n</tr>\n<tr>\n<td>5.4</td>\n<td>Reconstructed coefficients from first 230 codes</td>\n<td>79</td>\n</tr>\n<tr>\n<td>5.5</td>\n<td>Perfect reconstruction from all codes</td>\n<td>80</td>\n</tr>\n<tr>\n<td>5.6</td>\n<td>Input and output results from one parallel architecture encoder and decoder</td>\n<td>81</td>\n</tr>\n</tbody>\n</table>\nACKNOWLEDGEMENT\n\nProject Supervisor: Dr. Ganesh Kothapalli\n\nProject Examiners: Professor A. Bouzerdoum\nDr. Ganesh Kothapalli\n\nI would like to express my sincere gratitude to my supervisor, Dr. Ganesh Kothapalli for his continued advice and guidance throughout the course of this project. He spent a considerable amount of time out of his busy schedule to ensure the success of my project. I would also like to thank Dr. Stefan Lachowicz who supervised me during the first half of my project. He provided me with abundant amount of literature related to the project and also provided helpful guidance.\n\nI am also very thankful to Mr. Kenneth Ang and Geoffrey Alagoda, Ph.D. students in the engineering department at Edith Cowan University. Kenneth not only provided me with valuable consultation on the EZW algorithm, he also lent me a lot of recent books on the topic and gave advice on how to improve my thesis. Geoff also provided me with very useful consultation.\n\nMy thanks are also due to Mr. Richard Geissler, at the University of Ulm, Germany, who kindly and promptly clarified the many doubts I had on VHDL.\n\nLastly, I would like to thank my family and friends who have inspired me and given me unfaltering support throughout my education career.\n\nKarma Wangdi\nABSTRACT\n\nThis thesis discusses the findings of the final year project involving the VHDL (V= Very High Speed Integrated Circuit, Hardware Description Language) design and simulation of an EZT (Embedded Zero Tree) codec.\n\nThe basis of image compression and the various image compression techniques that are available today have been explored. This provided a clear understanding of image compression as a whole. An in depth understanding of wavelet transform theory was vital to the understanding of the edge that this transform provides over other transforms for image compression. Both the mathematics of it and how it is implemented using sets of high pass and low pass filters have been studied and presented.\n\nAt the heart of the EZT codec is the EZW (Embedded Zerotree Wavelet) algorithm, as this is the algorithm that has been implemented in the codec. This required a thorough study and understanding of the algorithm and the various terms used in it.\n\nA generic single processor codec capable of handling any size of zerotree coefficients of images was designed. Once the coding and decoding strategy of this single processor had been figured out, it was easily extended to a codec with three parallel processors. This parallel architecture uses the same coding and decoding methods as in the single processor except that each processor in the parallel processing now handles only a third of the coefficients, thus promising a much speedier codec as compared to the first one.\n\nBoth designs were then translated into VHDL behavioral level codes. The codes were then simulated and the results were verified.\n\nOnce the simulations were completed the next aim for the project, namely synthesizing the design, was embarked upon. Of the two logical parts of the encoder, only the significance map generator has been synthesized.\nINTRODUCTION\n\nDigital images play a crucial role of disseminating rich information in today's Information Age. Of the various types of data transferred over our networks, notably the Internet, image comprises the bulk of the traffic. Current estimates indicate that image data transfer take up over 90% of the volume on the Internet.\n\nAs ubiquitous and as informative as they are, digital images are also the most data intensive, requiring huge storage space and longer transmission and access time.\n\nIn order to utilize these digital images there are clearly needs for effective image compression techniques to reduce the number of bits required to represent them. A wide range of compression techniques has been developed over the years, and novel approaches continue to emerge.\n\nThe use of wavelet transform in image compression has captured the imagination and the talent of researchers all over the world in recent times. This wavelet image compression technique promises performance improvements over all the compression methods currently available. So promising is this technique of image compression that wavelet image coders are among the leading coders submitted for consideration in the upcoming JPEG200 standard, which will replace the current JPEG standard for image compression.\n\nThe most revolutionary thing about wavelet transform is that when applied to a digital image it executes a multiresolution analysis on the image. In other words, wavelet transform essentially processes the image in much the same manner as the human visual system.\n\nThe EZW (embedded zerotree wavelet) algorithm is one image compression algorithm based on this new technique. It is claimed to be a remarkably effective image compression algorithm. This algorithm has the property that bits in a bitstream are generated in the order of importance, yielding a fully embedded code. This property then allows the encoder to terminate the encoding at any point, thereby allowing a bit rate or a distortion rate to be met exactly. Also given a bitstream the decoder can\nterminate decoding at any point and still produce the same image that would have been encoded at the bit rate corresponding to the truncated bit stream.\n\nFrom EZW algorithm two codec (encoder and decoder) architectures have evolved in this project. The single processor architecture is the main architecture in the sense that the other is just a slight adaptation of the single processor to take advantage of the inherent parallelism present in the zerotree data structure.\n\nThe VHDL codes for the designs have been written at a behavioral level. Simulation and synthesis tools used were from Synopsys Inc.\nPROJECT DEFINITION\n\nAim\nThe main aim of the project was to design, simulate and if possible, synthesize, an EZT codec implementing the EZW algorithm. The objectives that this main aim of the project translated to were:\n\n- An understanding of image compression in general and that of wavelet image compression in particular.\n- A study of wavelet transform and how it relates to image compression.\n- A thorough understanding of the EZW algorithm and the various terms used in it.\n- A good mastery of the VHDL language\n- Design and simulation of a codec using VHDL behavioral level code.\n- Synthesis of the codec.\n\nScope\nThe project has both a research component and a VLSI implementation component in the form of VHDL implementation.\n\n- The first task was to understand image compression as a whole and the various features of images that have been exploited to achieve image compression. Models of image compression were also studied.\n- A good grasp of wavelet transform theory was paramount in understanding the EZW algorithm, which is at the heart of the project. How this transform relates to image compression was then investigated.\n• Of utmost importance was the thorough understanding of the EZW algorithm itself. IEEE transactions were a major source. Consultation with a PhD student working on a similar but advanced topic proved very helpful and productive.\n\n• Since the codec was to be implemented in VHDL, a good knowledge of the language was crucial as well. It was learnt in tandem with the reading of back ground materials.\n\n• VHDL tools used for simulation and synthesis were from Synopsys Inc. PeakVHDL was also used as an alternative simulation tool in the course of the project.\n1. INTRODUCTION TO IMAGE COMPRESSION\n\n1.1 Introduction\n\nIn many different fields, digitized images are replacing conventional analog images as photographs or x-rays. The volume of data required to describe such images greatly slows transmission and makes storage prohibitively costly. Image compression is the general term that addresses the problem of reducing the amount of data required to represent a digital image. The following paragraphs present some principles and techniques of image compression that are currently being used.\n\n1.2 Basis of Image Compression\n\nImage compression is based on two features of data; namely data redundancy and data irrelevancy. Hence the great variety of compression algorithms mainly differ in their approaches to extracting and exploiting these two features of data redundancy and irrelevancy. (Topiwala, 1998)\n\n1.2.1 Data Redundancy\n\nThe term data compression refers to the process of reducing the amount of data required to represent a given quantity of information. Various amounts of data may be used to represent the same amount of information. When there are more data than actually required to represent a given information the data is said to contain data redundancy.\n\nData redundancy is a central issue in digital image compression. Three basic data redundancies can be identified and exploited in digital image compression. They are:\n\n- Coding redundancy\n- Interpixel redundancy and\n- Psychovisual redundancy\n\n1.2.1.a. Coding Redundancy\nIn general, coding redundancy is present when the codes assigned to a set of events have not been selected to take full advantage of probabilities of the events. It is almost always present when an image's gray levels are represented with straight or natural binary code. In this, the underlying basis for coding redundancy is that images are typically composed of objects that have a regular and somewhat predictable morphology and reflectance, and are generally sampled so that the objects being depicted are much larger than the picture elements. The natural consequence is that, in most images, certain gray levels are more probable than others. If a natural binary coding of gray levels is used, the same number of bits are assigned to both the most and the least probable values, thus resulting in coding redundancy. (Gonzalez and Woods, 1993).\n\n1.2.1.b Interpixel Redundancy\n\nInterpixel redundancy is directly related to the interpixel correlations that exist within an image. Because the value of any given pixel can be reasonably predicted from the values of its neighbor's, the information carried by the individual pixels is relatively small. In other words much of the visual contribution of a single pixel to an image is redundant. A variety of names, including spatial redundancy, geometric redundancy and interframe redundancy, have been coined to refer to these interpixel dependencies. The term Interpixel redundancy encompasses them all. (Gonzalez and Woods, 1993). Interpixel redundancies are removed by using suitable transforms.\n\n1.2.1.c Psychovisual Redundancy\n\nPsychovisual redundancy is the result of the nature of the human eye. The eye does not respond with equal sensitivity to all visual information. Certain information simply has less relative importance than other information in normal visual processing. This information is said to be psychovisually redundant. It can be eliminated without significantly impairing the quality of image perception. (Gonzalez and Woods, 1993).\n1.2.2 Data Irrelevancy\n\nAn important example of data irrelevancy occurs in the visualization of gray scale images of high dynamic range, e.g., 12 bits or more. It is an experimental fact that for monochrome images, 6 to 8 bits of dynamic range is the limit of human visual sensitivity; any extra bits do not add perceptual value and can be eliminated. (Topiwala, 1998).\n\n\n\n1.3 Image Compression Models\n\n\n\nAs figure 1.2 shows, an image compression system consists of two distinct structural blocks: an encoder and a decoder. An input image \\( f(x,y) \\) is fed into the encoder which...\ncreates a set of symbols from the input data. After transmission over the channel, the encoded representation is fed to the decoder, where a reconstructed output image \\( f(x,y) \\) is generated. In general \\( f(x,y) \\) may or may not be an exact replica of \\( f(x,y) \\). If it is, the system is error free or information preserving; if not some level of distortion is present in the reconstructed image.\n\nBoth the encoder and the decoder shown in figure 1.2 consist of two relatively independent functions or subblocks. The encoder is made up of a source encoder which removes input redundancies, and a channel encoder which increases the noise immunity of the source encoder's output. As would be expected, the decoder includes a channel decoder followed by a source decoder. If the channel between the encoder and the decoder is noise free (not prone to error), the channel encoder and decoder are omitted, and the general encoder and decoder become the source encoder and decoder, respectively.\n\n1.3.1 The Source Encoder and Decoder\n\nThe source encoder is responsible for reducing or eliminating any coding, interpixel, or psychovisual redundancies in the input image. The specific application and associated\n\n\n\nFigure 1.3 (a) Source encoder and (b) Source decoder model\n\nKarma Wangdi\n\nfidelity requirements dictate the best encoding approach to use in any given situation. Normally, the approach can be modeled by a series of three independent operations.\n\nFigure 1.3(a) shows how each operation is designed to reduce one of the three redundancies mentioned in section 1.2. Figure 1.3(b) depicts the corresponding source decoder.\n\nIn the first stage of the source encoding, process the mapper transforms the input data into a (usually nonvisual) format designed to reduce interpixel redundancies in the input image. This operation is generally reversible and may or may not reduce directly the amount of data required to represent the image. Run length coding which will be explained in a later section is an example of a mapping that directly results in data compression in this initial stage of the overall source encoding process. The representation of an image by a set of transform coefficients is an example of the opposite case. Here the major mapper transforms the image into an array of coefficients, making its interpixel redundancies more accessible for compression in later stages of the encoding process.\n\nThe second stage, or quantizer block in figure 1.2(a), reduces the accuracy of the mapper's output in accordance with some pre-established fidelity criteria. This stage reduces the psychovisual redundancies of the input image. This operation is irreversible. Thus it must be omitted when error-free compression is desired. This block is what distinguishes between a lossy and a lossless compression. In the third and the final stage of the source encoding process, the symbol coder creates a fixed or variable length code to represent the quantizer output and maps the output in accordance with the code. The term symbol coder distinguishes this operation from the overall source encoding process. In most cases, a variable length code is used to represent the mapped and quantized data set. It assigns the shortest code words to the most frequently occurring output values and thus reduces coding redundancy. This operation is reversible. Upon completion of the symbol-coding step, the input image has been processed to remove each of the three redundancies.\n\nFigure 1.3 shows the source encoding process as three successive operations, but all three operations are not necessarily included in every compression system. For\nexample the quantizer must be omitted when error-free compression is desired. In addition, some compression techniques normally are modeled by merging blocks that are physically separate in Figure 1.2(a). For instance, in predictive compression systems, a topic discussed in a later section, the mapper and the quantizer are often represented by a single block that simultaneously performs both operations.\n\n1.4 Types of Image Compression Techniques\n\n![Image Compression Techniques Diagram]\n\nThere are many different approaches to image compression, but they can all be categorized into two fundamental groups: lossy compression techniques and lossless compression techniques.\n\nIn lossless compression (also known as bit-preserving or reversible compression), the reconstructed image after compression is numerically identical to the original image on a pixel-by-pixel basis. Since no information is compromised only a modest amount of compression is achieved. In other words the compression ratio (CR) is small. The compression ratio is defined as:\n\n\\[ CR = \\frac{\\text{No of bits for original image}}{\\text{No of bits for compressed image}} \\]\nIn lossy compression (also known as irreversible compression), the reconstructed image contains degradations relative to the original. As a result much higher compression can be achieved as compared to the lossless compression. The compression ratio is high.\n\nImage compression techniques can also be divided into transform and non-transform coding. In transform compression the image data are transformed into transform coefficients by applying some transform functions, such as DCT (discrete cosine transform and wavelet transform, and the resulting coefficients are encoded. In non-transform compression no such transformation is applied. Wavelet coding and JPEG are examples of transform coding while PCM and DPCM are examples of non-transform compression techniques.\n\nFigure 1.5 shows a general compression framework. It includes three components: image decomposition or transformation, quantization, and symbol generation. As we can see from the figure, the primary difference between lossy and lossless schemes is the inclusion of the quantization stage in the lossy compression technique, while it is absent in the lossless scheme.\n1.4.1 Lossless Compression Techniques\n\nIn this section we look at two main lossless compression techniques. They are Bit Plane Encoding and Lossless Predictive Coding.\n\n1.4.1.a Bit Plane Encoding\n\nBit plane encoding is a lossless and a non-transform compression technique. Consider an $N \\times N$ image in which a pixel value is represented by $k$ bits. By selecting a single bit from the same position in the binary representation of each pixel, an $N \\times N$ binary image called a bit plane can be formed. For example we can select the most significant bit of each pixel value to generate an $N \\times N$ binary image representing the most significant bit plane. Repeating this process for the other bit positions, the original image can be decomposed into a set of $k$, $N \\times N$ bit planes (numbered 0 for the least significant bit (LSB) plane through $k-1$ for the most significant (MSB) plane. Each bit plane is then encoded efficiently using a lossless binary compression technique like Run Length Encoding and Arithmetic Encoding.\n\n\n\n**Figure 1.6** An image whose pixel values are $k$ bits wide decomposed into $k$ bit planes\n\n- k-1 bit plane\n- k-2 bit plane\n- ... \n- 1 bit plane\n- 0 bit plane\n\nk-1 bit plane contains the most significant bits form all the pixel values in order similarly k-2 contains the next most significant bits from all the pixel values in order and so on.\n1.4.1.b Lossless Predictive Coding\n\nFor typical images, the values of adjacent pixels are highly correlated; that is, a great deal of information about a pixel value can be obtained by inspecting its neighbouring pixels. This property is exploited in predictive coding techniques where an attempt is made to predict the value of a given pixel based on the values of the surrounding pixels. The new information of a pixel is defined as the difference between the actual and the predicted value of the pixel.\n\n\\[ e_n = f_n - f'_n \\]\n\nwhich is coded using a variable length code. The decoder reconstructs \\( e_n \\) from the received variable length code words and performs the inverse operation.\n\n\\[ f_n = e_n + f'_n \\]\n\nFigure 1.7 shows the basic components of a lossless predictive coding system. The system consists of an encoder and a decoder, each containing an identical predictor. As each successive pixel of the input image, denoted \\( f_n \\), is introduced to the encoder, the predictor generates the anticipated value of that pixel based on some number of inputs. The output of the predictor is then rounded to the nearest integer, denoted \\( f'_n \\), and used to form the prediction error.\n1.4.2 Lossy Compression Techniques\n\nThere are a lot of lossy compression techniques available and as a result it isn’t feasible to cover all of them. We will instead look at some of the most prominent ones in this section.\n\n1.4.2.a Discrete Cosine Transform Coding\n\nDiscrete Cosine Transform (DCT) is a popular transform image compression technique. The JPEG image format uses DCT method. (Topiwala, 1998) In DCT the image is divided into blocks or rectangular arrays of pixels. Most existing systems use blocks of regular size, such as 8 x 8 or 16 x 16 pixels. Larger block sizes lead to more efficient coding, but require more computational power.\n\n\n\n*Figure 1.8 8 x 8 DCT basis Functions\nAdopted from Rabbani and Jones (1991)*\n\nThe DCT is applied to each block that converts a block of pixels into a block of DCT coefficients of the same dimensions. These coefficients represent the spatial frequency components that make up an appropriate basis function. The basis function for 8 x 8 DCT are shown in figure 1.8. The top left function is the basis function of the ‘dc’ coefficient and represents zero spatial frequency. Along the top row the basis functions\nhave increasing horizontal spatial frequency content. Down the left column, the functions have increasing vertical spatial frequency content, and along the diagonal the functions have combination of vertical and horizontal spatial frequencies.\n\nThe resulting coefficients are then quantized using uniform quantization step sizes. The quantized DCT coefficients are then scanned in a specific diagonal order, starting from the \"dc\" or 0-frequency component, then run-length coded, and finally entropy coded according to either Huffman or arithmetic coding. (Topiwala, 1998)\n\n1.4.2.b Vector Quantization\n\nIn vector quantization (VQ) method, the original image is first decomposed into n-dimensional image vectors. The vectors can be generated in a number of different ways. For example, an \\( n = l \\times m \\) block of pixel values can be ordered to form an n-dimensional vector.\n\n\n\nEach image vector, \\( X \\), is then compared with a collection of representative templates or codevectors \\( X'_i \\) taken from a previously generated codebook. The code vectors are also of dimension \\( n \\). The best match codevector is chosen using a minimum distortion rule.\nAfter a minimum distortion codevector has been selected, its index $k$ is transmitted. At the receiver this index is used as an entry to a duplicate codebook to reproduce the original codevector.\n\n### 1.4.2.c Wavelet Coding\n\nWavelet coding is one of the most recent techniques of image compression that has been developed. This technique uses the wavelet transform to remove the spatial correlation that exists in images. The wavelet transform coefficients that are obtained contain the information in a compact smaller number of coefficients. These coefficients are then quantized and then efficiently coded using suitable coding algorithms.\n\nImage coding using using wavelet transform exhibits several desirable qualities. Since the wavelet transform executes a multiresolution analysis on the image, it essentially processes the image in much the same way as the human visual system does. The importance of the resulting transform coefficients to the reconstructed image is then easily evaluated for coding purpose. The wavelet transform enjoys a considerable amount of design freedom in the choice of the basis wavelet. By proper choice of the analyzing wavelet, the wavelet transform can be tailored to a specific style of implementation.\n\nSince this project work focus on the EZW algorithm of wavelet coding, wavelet coding method is very well explained in the chapters ahead.\n\n### 1.4.2.d Lossy Plus Lossless Residual Coding\n\nAnother way of image compression is to mix both the lossy and the lossless techniques. One such technique is the Lossy Plus Lossless Residual coding. Lossy Plus Lossless Residual coding is used in application where it suffices to send a lossy version of the image first and then the lossless version afterwards as needed. One such application might exist in the medical field, where two physicians are discussing a possible patient referral from remote locations. One of the physicians may wish to transmit a digital radiograph over the phone line, and in the interest of a short transmission time, a lossy...\n(but high quality) version of the image is sent. If the referral is accepted, the remaining difference (residual) image required to perfectly reconstruct the original image could be sent.\n\nIn general a lossy plus a lossless residual encoding scheme consists of the following steps:\n\n- Generate a low bit rate image through the use of an efficient lossy scheme.\n- Form a residual by computing the difference between the lossy reconstruction and the original image.\n- Encode the residual using an appropriate lossless technique.\n2. WAVELET TRANSFORM AND IMAGE COMPRESSION\n\n2.1 Introduction\n\nWavelet transforms, as an alternative to the Fourier and related transforms, for application to practical engineering problems have been the focus of intensive research in recent years. The concept of Wavelet itself was introduced quite recently in 1984 by Goupillaud, Grossman and Morlet as a new mathematical tool for multiresolution decomposition of continuous-time signals. This mathematical tool for multiresolution analysis of signals has been investigated and applied in various fields including geophysics, image analysis for the purpose of segmentation, pattern recognition and coding. The incentive for this is its ability to provide a multiresolution or multiscale analysis of signals with flexible space-frequency localization.\n\nIn the field of image compression wavelets have captured the imagination and talents of researchers all over the world. A number of researches that wavelet transform holds considerable promise in image compression. The most revolutionary thing about wavelet transform is that since it executes a multiresolution analysis on the image, it essentially processes the image in much the same manner as the human visual system. (Coffey and Etter, 1995).\n\n2.2 Mathematical Representation of Wavelets\n\nWavelets are functions generated from one single function, the mother wavelet \\( \\psi \\) by dilation and translation. Grossman and Morlet (Grossman and Morlet, 1984) introduced this function \\( \\psi \\) which dilated by a scaling factor \\( a \\) and translated by \\( b \\) enables the analysis, processing, and synthesis of a signal.\n\n\\[\n\\psi_{a,b}(x) = |a|^{-1/2} \\psi \\left( \\frac{x-b}{a} \\right) \\quad (a, b) \\in \\mathbb{R}^2, \\ a \\neq 0\n\\] \n(1-1)\n\nIt is assumed that \\( x \\) is a one dimensional variable. The mother wavelet \\( \\psi \\) must satisfy the following admissibility condition.\n\\[ \\int \\frac{|\\psi(\\omega)|^2}{|\\omega|} d\\omega < \\infty \\quad (1-2) \\]\n\nwhere \\( \\Psi \\) denotes the Fourier transform of \\( \\psi \\). Moreover if \\( \\psi \\) has sufficient decay, then (1-2) is equivalent to\n\n\\[ \\int \\psi(x) dx = 0 \\quad (1-3) \\]\n\nwhich means that the wavelet \\( \\psi \\) exhibits at least a few oscillations, and that there is a large choice of functions for \\( \\psi \\).\n\nThe basic idea of the wavelet transform is to represent an arbitrary function \\( f \\) as a superposition of wavelets. This function \\( f \\) can then be decomposed at different scale or resolution levels. One way to achieve such a decomposition involves writing \\( f \\) as an integral of \\( \\psi_{a,b} \\) over \\( a \\) and \\( b \\) using appropriate weighting coefficients. In practice, however, it is preferable to express \\( f \\) as a discrete sum rather than as an integral. The coefficients \\( a \\) and \\( b \\) are discretized such that:\n\n\\[ a = a_0^m \\text{ and } b = nb_0a_0^m \\text{ with } (m,n) \\in \\mathbb{Z}^2 \\text{ and } a_0 > 1, \\ b_0 > 0 \\text{ fixed.} \\]\n\nThe wavelet is then defined as follows:\n\n\\[ \\psi_{m,n}(x) = \\psi_{a_0^m, nb_0}^m(x) = a_0^{-m/2} \\psi(a_0^{-m}x - nb_0) \\quad (1-4) \\]\n\nand the wavelet decomposition of \\( f \\) becomes\n\n\\[ f = \\sum_{m,n} c_{m,n}(f) \\psi_{m,n} \\quad (1-5) \\]\n\nFor large positive values of \\( m \\) (\\( a > 1 \\)), the \\( \\psi \\) function is highly dilated and large values for the translation step \\( b \\) are well adapted to this dilation. This corresponds to low frequency or narrow band-wavelets. For large values of \\( m \\) (\\( a < 1 \\)), the \\( \\psi \\) function is highly concentrated and the translation step \\( b \\) takes small values. These functions correspond to high frequency or wide band wavelets.\nY. Meyer showed that there are \\( \\psi \\) functions for \\( a^0 = 2 \\) and \\( b^0 = 1 \\), such that the functions \\( \\psi_{m,n}(x) \\) make up an orthonormal basis belonging to \\( L^2(\\mathbb{R}) \\), where\n\n\\[\n\\psi_{m,n}(x) = 2^{-m/2} \\psi(2^{-m} x - n) \\quad (m,n) \\in \\mathbb{Z}^2\n\\]\n\n(\\( \\mathbb{Z} \\) is the set of all integers and \\( \\mathbb{R} \\) is the set of all real numbers and \\( \\mathbb{N} \\) is the set of all Natural numbers)\n\nThe wavelet coefficients \\( C_{m,n}(f) \\) are determined using the following relation:\n\n\\[\nc_{m,n}(f) = \\langle f, \\psi_{m,n} \\rangle = \\int f(x) \\overline{\\psi}_{m,n}(x) \\, dx\n\\]\n\nThe oldest known basis of this type was constructed by Haar. In this case, the function \\( \\psi(x) \\) is equal to 1 over the interval \\([0,1/2]\\), -1 over \\([1/2, 1]\\) and 0 elsewhere. Different bases corresponding to more regular wavelets were later constructed by Stromberg, Meyer, Lemarie, Battle, and Daubechies.\n\nThe existence of orthonormal wavelet bases is conditioned by the following regularity property: \\( |\\psi(\\omega)| \\) must decrease more rapidly than \\( C(1 + |\\omega|)^{-\\varepsilon} \\) for \\( \\omega \\to \\infty \\) and for \\( \\varepsilon > 0 \\); where \\( C \\) is a constant. Wavelets which exhibit this regularity property necessarily verify:\n\n\\[\n\\int x^r \\psi(x) \\, dx = 0\n\\]\n\nThis equation determines the number of vanishing moments of \\( \\psi \\) and thus enables evaluation of the oscillations of the wavelet \\( \\psi \\)\n\n### 2.3 Continuous Wavelet Transform\n\nTo perform wavelet transform on a time-domain signal, the signal is passed through various high-pass and low-pass filters, which filter out either high frequency or low frequency portions of the signals. Figure 2.1 shows how a wavelet transform is performed on a signal \\( x(t) \\) which has a maximum frequency of \\( B \\) Hz.\nThis is how it works: Suppose we have a signal that has frequencies up to 1000 Hz. In the first stage the signal is split into two parts by passing the signal through a high-pass and a low-pass filter. Which result in two different versions of the same signal; portion of signal corresponding to 0-500Hz (low-pass portion) and 500-1000Hz (high-pass portion). Then we take either portion or both and pass them through another set of high and low pass filters. This operation is called decomposition.\n\nAssuming that we took the low pass output from the first filtering and performed the second decomposition, we have three sets of data now, each corresponding to the same signal frequencies 0-250 Hz, 250-500Hz and 500-1000Hz. If we take the low pass portion and pass it through low and high pass filters, we now have four sets of signals corresponding to 0-125Hz, 125-250Hz, 250-500Hz and 500-1000Hz.\n\n\n\nIn this way we continue to decompose a signal until we have decomposed the signal into a certain predefined level. At the end we have a bunch of signals, which actually represent the same original signal, but all corresponding to different frequency bands. If the resulting signal is plotted on a 3-D graph, we will have time in one axis, frequency in the other and amplitude in the third. This will show us which frequencies exist at which time. In other words the resulting signal can be resolved both in time as well as in frequency.\n\nKarma Wangdi \nHowever there is a principle known as the uncertainty principle which states that \"we cannot exactly know what frequency exists at what time instance, but we can only know what frequency bands exist at what time intervals\". This is analogous to the uncertainty principle in quantum Physics ascribed to Heisenberg that states \"the momentum and the position of an electron can not be determined simultaneously\". This is a problem of resolution, and it is the main reason why researchers have switched from STFT (short time Fourier transform) to WT (wavelet transform). STFT also resolves a signal in both frequency and time, but it gives a fixed resolution at all times whereas WT gives variable resolution.\n\n2.3.1 Resolution from Continuous Wavelet Transform\n\nHigher frequencies are better resolved in time, and lower frequencies are better resolved in frequency. This means that a certain high frequency component can be located better in time (with less relative error) than a low frequency component. On the contrary, a low frequency component can be located better in frequency compared to high frequency component.\n\nThe grid in the figure 2.2 is interpreted as follows: The top row shows that higher frequencies we have more samples corresponding to smaller intervals of time. In other words, higher frequencies can be resolved better in time. The bottom rows correspond to low frequencies, and there is less number of points to characterize the signal. Therefore low frequencies are not well resolved in time.\n2.4 Discrete Wavelet Transform\n\nThe Discrete Wavelet Transform (DWT) is the analog of the continuous wavelet transform (CWT) presented in the previous section, in the discrete time domain. A time-scale (scale and frequency have inverse relationship) representation of a digital signal is obtained using digital filtering techniques. As in the continuous time the digital signal is passed through a series of low and high pass filters.\n\nThe procedure starts with passing the signal (sequence, since discrete) through a half band digital low pass filter with impulse response $h[n]$ and a half band digital high pass filter with impulse response $g[n]$. Filtering a signal is a mathematical operation of convolution of the signal with the impulse response of the filter. The convolution in discrete time is defined as follows.\n\n$$x[n] * h[n] = \\sum_{k=-\\infty}^{\\infty} x[k] \\cdot h[n-k]$$\n\nThe pair of high pass and low pass filters are not independent but are related by\n\n$$g[L-1-n] = (-1)^n \\cdot h[n]$$\n\nA half band low pass filter removes all frequencies that are above half of the highest frequency in the signal, while the high pass filter removes all the frequency components that are below half of the highest frequency in the signal. The resultant sequence is passed through another set of high and low pass filters and the process continues until a certain desired level of decomposition is done. The algorithm is shown in figure 2.3.\n\nAs an example, suppose that $x[n]$ has 512 sample points, spanning a frequency of zero to $\\pi$ radians. At the first decomposition level, the sequence is passed through high pass and low pass filters, followed by subsampling by 2. The high pass filter has 256 points, but it only spans the frequency range $\\pi/2$ to $\\pi$ radians. These 256 samples constitute the first level of DWT coefficients. The output of the low pass filter has 256 points, and it spans the frequency band from 0 to $\\pi/4$ radians. This sequence is then passed through similar low pass and high pass filters for further decomposition. The output of the second low pass filter followed by subsampling has 128 samples spanning a frequency band of 0 to $\\pi/4$ radians, and the output of the second high pass filter followed by\nsubsampling has 128 samples spanning a frequency band $p/4$ to $p/2$. The second high pass filter samples constitute the second level of DWT coefficients. This signal has half the time resolution, but twice the frequency resolution of the first level signal. In other words, time resolution has decreased by a factor of 4, and frequency resolution has increased by a factor of 4 compared to the original signal. The low pass filter output is then filtered once again for further decomposition. This process continues until two sample is left. For this specific example there would be 9 levels of decomposition, each having half the number of samples of the previous level. The DWT of the original signal is then obtained by concatenating all coefficients starting from the last level of decomposition (remaining one sample, in this case). The DWT will then have the same number of coefficients as the original signal.\n\n2.4.1 Resolution from Discrete Wavelet Transform\n\nIn the discrete time case, the time resolution of the signal works the same as in the continuous time case, but with one exception. The frequency information has different\nresolutions at every stage too. Lower frequencies are better resolved in frequency, whereas higher frequencies are not. Figure 2.4 shows the time – frequency resolution offered by discrete time wavelet transform.\n\nLooking at figure 2.4 it is noticed how the spacing between subsequent frequency components increase as frequency increases. (Robi Polikar, 1994)\n\n2.5 Wavelet Transform and Digital Image Compression\n\nWavelet transform has opened up a whole new prospect for efficient image compression and wavelet transform technique of image compression has gained a lot of popularity in the last couple of years. Following are some of the most important reasons.\n\n2.5.1 Data Compression\n\nWhen a DWT is performed on a signal, frequencies that are most prominent in the original signal appear as high amplitudes in that region of the DWT signal that includes those particular frequencies. The frequency bands that are not very prominent in the original signal have very low amplitudes and that part of the DWT signal can be discarded without any major loss of information, thus allowing data reduction. In other words, wavelet transform concentrates the original signal values into a relatively small number of large magnitude coefficients. (Relue, 1994) Figure 2.5 illustrates the data reduction obtained.\n\nIn practice all but a few percent of the wavelet coefficients can be set to zero. (Relue, 1994). Selection of the coefficients can be done in two ways:\n- An arbitrary threshold can be established as the cutoff point\n- The coefficients can be ranked to allow selecting of an arbitrary percentage of the highest values for retention.\n\nTypically, 5 percent of the values are retained, but good results can be obtained with smaller percentages. In image compression it is important to note that the zeroed coefficients cannot be thrown away. The position of the zeroed coefficients must still be known for reconstruction. (Rajue, 1994)\n\nOnce the data have been compressed by the removal of low value coefficients, more compression can be obtained by quantizing the non-zero wavelet coefficients.\n\n\n\n**2.5.2 Better Frequency Resolution**\n\nThe bulk of the information in images is found in lower frequency bands. We have already seen in figure 2.4 that discrete wavelet transform provides better frequency resolution at lower frequency. This means that we can have better resolution of our images using wavelet transform.\n2.5.3 Noise Immunity\n\nThe compression process using wavelet transform has an interesting side effect. Since most of the noise in an image has low energy value, it will be suppressed when reconstructing the compressed data. Figure 2.6 shows a sine wave with 50 percent noise added, and the reconstructed sine wave from 3 percent of the original data using Daubechies 2-D transform. The original sine wave is very easy to distinguish in the reconstruction. (Savla, 1998)\n\n\n\n(a) Original(noisy)\n(b) Transformed\n\nAdapted from Savla, 1998\n\n\n\nAdapted from Savla, 1998\n\nThe reconstruction of low noise signal is generally very good. Simple waveforms such as a sine wave can be done with 3 percent of the data as illustrated in Figure 2.7\n3. THE EZW ALGORITHM\n\n3.1 Introduction\n\nIn the last chapter we studied the wavelet transform and how it is performed in both continuous and discrete time domains. We then observed the results of wavelet transform on signals and particularly related the results to image coding. And we found that wavelet transform holds considerable promise for image compression.\n\nIn this chapter we present the EZW (Embedded Zerotree Wavelet) algorithm, which is an image compression algorithm formulated by J.M. Shapiro.\n\nThe EZW algorithm has the property that the bit streams are generated in the order of importance and all information is contained within the code thereby yielding a fully embedded code. Using this algorithm the encoder can terminate the encoding at any point thereby allowing the target rate or target distortion metric to be met. Also, given a bit stream the decoder can cease decoding at any point in the bit stream and still produce exactly the same image that would have been encoded at the bit rate corresponding to the truncated bit stream. (Shapiro, 1993)\n\n3.2 Features of the Embedded Coder\n\nThe EZW algorithm contains the following features:\n\n- A discrete wavelet transform which provides a compact multiresolution representation of the image\n\n- Zerotree coding which provides a compact multiresolution representation of significance maps, which are binary maps indicating the position of the significant coefficients. Zerotrees allow the successful prediction of significant coefficients across scales to be efficiently represented as part of exponentially growing trees.\n• Successive approximation which provides a compact multiresolution representation of the significant coefficients and facilitates the embedding algorithm.\n\n• A prioritization protocol whereby the ordering of importance is determined, in order, by precision, magnitude, scale, and spatial location of the wavelet coefficients. Larger coefficients are deemed more important than smaller coefficients regardless of their scale.\n\n• Adaptive multilevel arithmetic coding which provides a fast and efficient method for entropy coding of symbols, and requires no training or pre-stored tables.\n\n• The algorithm runs sequentially and stops whenever a bit rate is met.\n\nFigure 3.0 shows a generic transform coder.\n\n\n\n### 3.3 2-D Discrete Wavelet Transform of Image\n\nBefore the algorithm can be employed, the image is 2-D discrete wavelet transformed and wavelet coefficients for the image are obtained. It is these wavelet coefficients that are encoded using the algorithm.\n\n\n\n\nFigure 3.1 shows the result of first stage of wavelet transform of an image. Because we are dealing with digital image compression here, whenever we say wavelet transform, it should be understood as the discrete wavelet transform.\n\nAs explained in the previous chapter, the four subbands in figure 3.1 arise from the separable application of vertical and horizontal filters. The subbands LH1, HL1 and HH1 represent the finest scale wavelet coefficients. To obtain the next coarse scale of wavelet coefficients, the subband LL1 is further decomposed. To obtain the third scale level of wavelet coefficients, as shown in figure 3.2 the subband LL2 is further decomposed. As could be obvious, in the figure, the first letter of the L and H combination refers to the horizontal filter outcome and the second letter refers to the vertical filter outcome. The subscript indicates the number of scales. For example HL2 indicates that it is the outcome of the high pass horizontal filter and the low pass vertical filter of scale 2.\n\nSince we know that $-\\pi \\leq \\omega \\leq \\pi$ for discrete signals, in figure 3.1 the low frequencies represent a bandwidth approximately corresponding to $0 \\leq |\\omega| \\leq \\pi/2$ while the high frequencies correspond to $\\pi/2 \\leq |\\omega| \\leq \\pi$. With each level of decomposition these bandwidths get halved from the previous ones.\n\n### 3.4 The Zerotree Data Structure\n\nThe wavelet coefficients in one subband have a parent child relationship with the wavelet coefficients in other subbands when significance with regard to particular threshold value is concerned. This gives rise to a new data structure called the zerotree which improves the coding of the wavelet coefficients. A wavelet coefficient $x$ is said to be insignificant with respect to a threshold $T$ if $|x| < T$. The zerotree is based on the hypothesis that if a wavelet coefficient at a coarse level is insignificant with respect to a given threshold $T$, then all wavelet coefficients of the same orientation in the same spatial location at finer scales are likely to be insignificant with respect to $T$. This hypothesis is found to be often true. (Shapiro, 1993). Figure 3.3 shows the parent child relationship of the coefficients in the subbands.\nThe coefficient at the coarse scale is called the parent, and all coefficients corresponding to the same spatial location at the next finer scale of similar orientation are called children. For a given parent the set of all coefficients at all finer scales of similar orientation corresponding to the same location are called descendents. Similarly for a given child, the set of all coefficients at all coarser scales of similar orientation corresponding to the same location are called ancestors. With the exception of the lowest frequency subband, all parents have four children. For the lowest frequency\n\n\n\nsubband, the parent-child relationship is defined such that each parent node has three children.\n\nIn Figure 3.3 the arrow points from the subband of the parents to the subbands of the children. LL₃ the lowest frequency subband is at the top left. Also shown are the children and the descendents of HH₃.\n\n### 3.5 The Number of Zerotrees\n\nDepending on the number of scales of decomposition that is performed we get different number of zerotrees of the wavelet coefficients. If there is only one coefficient remaining in the LLₙ for an n-scale decomposition then we get one tree. Otherwise we get multiple trees. This is important to understand because in some cases we don't need to decompose so that there is just one coefficient left in the lowest frequency band LLₙ. As a rule of thumb, for image size like 512 x 512, only five or six scales of decomposition\nare performed. If we decompose the above 512 x 512 to five scales, we end up with eight coefficients in the LL₅ subband, and so we have eight trees. In fact the number of trees is equal to the number of coefficients in the lowest frequency subband (LL₀). In Figure 3.4 shows an 8 x 8 wavelet coefficients from three-scale decomposition so that there is only one tree, and Figure 3.5 shows the same 8 x 8 wavelet coefficients but from only two-scale decomposition and thus resulting in four trees. The members/coefficients of each different tree are differentiated by representing them by *, +, -, and -. Figure 3.6 shows one tree structure in a tree-like representation.\n3.6 The Significance Map\n\nThe significance map contains the significance information of coefficients in a tree. It contains information whether a coefficient’s descendents are significant or not and whether its ancestors are significant or not. This significance information or significance map is very useful when encoding a coefficient code as zerotree root or an isolated zero. The idea will become clear when we discuss section 3.8.\n\n3.7 Scanning of Coefficients\n\nTo process the coefficients, the scanning of coefficients is performed in such a way that no child node is scanned before its parent. For an n-scale transform, the scan begins at the lowest frequency subband, denoted as LL_n, and scans subbands HL_n, LH_n, and HH_n, at which point it moves on to the scale n-1, and so on. The scanning pattern for 3-scale wavelet transform coefficients is shown in Figure 3.6. We note that each coefficient within a given subband is scanned before any coefficient in the next subband.\n\n\n\n3.8 Encoding a Wavelet Coefficient\n\nGiven a threshold level T we now discuss how a coefficient is encoded. A coefficient can be any one of the following four:\n\n- A positive significant\n- A negative significant\n- A Zerotree root, and\n• An Isolated zero\n\nA coefficient $x$ is significant with respect to a threshold value $T$ if $|x| \\geq T$. A significant coefficient is positive significant if it is positive and negative significant if it is negative.\n\nA coefficient $x$ is a zerotree root if itself and all its descendents are insignificant with respect to a threshold $T$.\n\nA coefficient $x$ is an isolated zero if it is itself insignificant but at least one of its descendents is significant.\n\nAccordingly four different symbols, one for each of the four kinds of coefficients that can be encountered can be assigned. Four such symbols can be as shown in Table 3.1\n\n<table>\n<thead>\n<tr>\n<th>Symbol</th>\n<th>Meaning</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>POS</td>\n<td>Positive</td>\n</tr>\n<tr>\n<td>NEG</td>\n<td>Negative</td>\n</tr>\n<tr>\n<td>ZTR</td>\n<td>Zerotree Root</td>\n</tr>\n<tr>\n<td>IZ</td>\n<td>Isolated Zero</td>\n</tr>\n</tbody>\n</table>\n\nTable 3.1 Symbols and their meanings for coding a wavelet coefficient\n\n\n\nFigure 3.8: Flow Chart for encoding a coefficient of the significance map\nIn this project these symbols and their meanings are used. The flow chart for encoding a coefficient is shown in Figure 3.8\n\n3.9 Successive Approximation Quantization\n\nTo perform the embedded coding, successive-approximation quantization (SAQ) is applied. The SAQ sequentially applies a sequence of thresholds $T_0$ to $T_{n-1}$ to determine the significance, where the thresholds are chosen so that $T_i = T_{i-1}/2$. The initial threshold is chosen such that $T_0 > |X_1|/2$ where $X_1$ is the maximum of all the transform coefficients.\n\nDuring the encoding and decoding, two separate lists of wavelet coefficients are maintained. These lists are called the dominant list and the subordinate list. At any point in the process, the dominant list contains the coordinates of the coefficients that have not yet been found significant in the same relative order as the initial scan. The scan is such that the subbands are ordered, and within each subband, the set of coefficients is ordered. Thus using the ordering of the subbands as shown in figure 3.6, all coefficients in a given subband appear on the initial dominant list prior to coefficients in the next subband. The subordinate list contains the magnitudes of those coefficients that have been found to be significant. For each threshold the list is scanned once.\n\nDuring the dominant pass, scanning the coefficients with coordinates on the dominant list, i.e. scanning the coefficients that have not been found significant, are compared to the threshold $T_i$ to determine their significance, and sign if they are found to be significant. The significance map is zerotree coded as described in section 3.8. Each time a coefficient is encoded as significant, (positive or negative significant), its magnitude is appended to the subordinate list. Then the coefficient in the wavelet transform array is set to zero, so that the significant coefficient does not prevent the occurrence of a zerotree on future dominant passes at smaller thresholds.\n\nAfter a dominant pass a subordinate pass is performed. During this subordinate pass the subordinate list is scanned and the specifications of the magnitudes available to the decoder are refined to an additional bit of precision. Specifically, during a subordinate pass the width of the width of the quantizer step size, which defines the uncertainty interval of the true magnitude of the coefficient, is halved. For each magnitude on the\nsubordinate list, this refinement can be encoded using a binary bit \" symbol to indicate that the true value falls in the upper half of the old uncertainty level. We should note that prior to this refinement, the width of the uncertainty level is exactly equal to the current threshold. After the completion of the subordinate pass the magnitudes of the subordinate lists are sorted in decreasing magnitude, to the extent that the decoder has the information to perform the same sort.\n\nThe process continues to alternate between the dominant and the subordinate passes where the threshold is halved before each dominant pass. In principle one could divide by any factor other than 2. The factor of 2 is chosen because it has nice interpretations in terms of bit plane encoding and numerical precision in a familiar base 2, and good coding results were obtained. (Shapiro, 1993)\n\nIn the decoding operation, each decoded symbol, both during the dominant and the subordinate passes, refines and reduces the width of the uncertainty level in which the true value of the coefficient may occur. The center of the uncertainty interval is used as the reconstruction value.\n\nThe encoding stops when some target stopping condition is met, such as when a bit budget is exhausted. The encoding can cease at any time and the resulting bit stream contains all lower rate encodings. Further more decoding can stop at any point. However terminating the decoding of an embedded bit stream at a specific point in the bit stream produces the same image that would have resulted had that point been the encoding target rate. This ability to cease encoding and decoding anywhere is extremely useful in systems that are either rate-constrained or distortion-constrained.\n\n3.10 Experimental Results Obtained by Shapiro\n\n- The compression performance of this algorithm was found to be competitive with virtually all known techniques.\n\n- The precise rate control that is achieved with this algorithm is a distinct advantage.\n• The performance of the EZW coder was compared to widely available version of JPEG. JPEG does not allow the user to select a bit rate but instead allow the user to choose a \"quality factor\".\n\n• A \"Barbara\" black and white picture was first encoded using a file size of 12,866 bytes. The PSNR (peak signal to noise ratio) in this case was found to be 26.99 dB. To the same \"Barbara\" picture EZW algorithm was applied with the same target file as above of exactly 12,866 bytes. The resulting PSNR was 29.39 dB, which is significantly higher than for the JPEG. The EZW encoder was then applied to the same picture using the target PSNR of 26.99 dB. The resulting file size was 8820 bytes.\n\n• When encoding or decoding is terminated during the middle of a pass, there are no artifacts produced that would indicate where the termination occurred.\n\n• A \"Lena\" image was coded at high compression ratio of 512:1. The image quality was poor but still recognizable. This is not the case with conventional block coding schemes, where at such a high compression ratio, there would not be enough bits to even encode the DC coefficients of each block. (Shapiro, 1993)\n4. ENCODER AND DECODER DESIGN\n\n4.1 Introduction\n\nThis chapter is divided into three parts. In Part A, the design of a single processor encoder is presented. Part B deals with the design of single processor decoder. In part C the design of codec using three parallel processors to process a zerotree of wavelet coefficients is presented using the principles of the single processor codec design.\n\nThe design of the codec described in this chapter is very generic and can be used to encode and decode any size zerotree of wavelet coefficients. In keeping with the specification of the project, the coefficient values are assumed to be between -128 and +127, which is for an 8 bit implementation. However the ideas can be applied for higher value coefficients.\n\nA. Encoder Design\n\n4.2 Single Processor Architecture\n\nHere we look at the architecture of the single processor encoder. The encoder that uses three parallel processors is explained afterwards. This is helpful because it becomes...\nfairly easy to grasp the idea once we have discussed the single processor encoder. Figure 4.1 shows a generic encoder.\n\n4.2.1 Mapping Coefficients to Memory Bank\n\nLet the tree size be $m$. For an $n \\times n$ image that has been wavelet transformed to a single coefficient for the lowest frequency subband, $m = n^2$. If the image has been wavelet transformed so that there are $k$ coefficients in the lowest frequency subband then the number of trees is $k$ and so each tree size $m = n^2/k$. \n\nFigure 4.2. One-to-one mapping of the coefficients in a tree to a memory bank.\nAs figure 4.2 shows these $m$ coefficients are then mapped into a memory bank, from 0 to $m-1$. The main parent goes to the index 0 memory element followed by its three children which are in turn followed by their children and so on. The coefficient number in the tree and the indices of the memory bank has one to one correspondence. For example the coefficient number 0 goes into the memory element whose index is 0, coefficient 1 goes into the memory element 1 and so on. The ordering of the coefficients is dictated by the scanning order that was shown in figure 3.3 in chapter 3.\n\n<table>\n<thead>\n<tr>\n<th>Coef</th>\n<th>Encoded</th>\n<th>ZTF</th>\n<th>DSig</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>2</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**Figure 4.3** The memory bank with the four fields\n\n### 4.2.2 Fields of a Memory Element\n\nEach element of the memory bank is not just a single field containing the coefficient alone, but a record of four fields. The fields are Coeff, DSig, ZTF, and Encoded. The memory bank actually looks as shown in figure 4.3. The fields facilitate the encoding process by containing important information with regard to the coefficient. The functions and meanings of these fields are as follows:\n\n- The Coeff field where the coefficient is actually stored.\n\n- The DSig field is used to store information to indicate if any of the descendents of the coefficient is significant with respect to a given threshold. A binary ‘1’ is to indicate ‘yes’ and the ‘0’ is for ‘no’. \n\nKarma Wangdi \n• The ZTF field is used to store the binary information to indicate if ancestor or parent of the coefficient has been found to be a zerotree root. In other words it is used to indicate if the coefficient is an element of a zerotree. Here too '1' is to indicate that the coefficient is an element of the zerotree while a '0' indicates that it is not.\n\n• The Encoded field is also used to store binary information to indicate if the coefficient has already been encoded. A '1' is meant to indicate yes and a '0' for no.\n\n4.2.3 Pointers\n\nAs shown in figure 4.1 we use two pointers called the parent pointer and the child pointer. As the names indicate, the parent pointer is used to point to the parent coefficient while the child pointer is used to point to the child coefficient.\n\n4.3 Choice of Thresholds\n\nThe specification for the encoder is for an 8-bit implementation. As such the coefficients can vary from -128 to 127. So the absolute value of the coefficients vary from 0 to 128. Instead of choosing the first threshold $T_i = \\frac{\\text{max}}{2}$ where $\\text{max}$ is the maximum of all coefficients, we choose 64 as the first threshold as it is half of the maximum possible threshold. The other thresholds then become 32, 16, 8, 4, 2 and 1. This choice of thresholds leads to a very simple and effective way of encoding the coefficients, as we will see later. It is especially useful when performing successive approximation.\n\nSubsequently we start encoding using the first threshold, 64. Then encode the whole tree against 32 then for 16 and so on until we have finished coding against threshold value 1.\n\n4.4 Encoding the Coefficients\n\nThe encoding of the coefficients against any threshold ($T$) is achieved by three operations. These three operations are:\n\n• Significance Map Generation\n- Assignment of Codes, and\n- Successive Approximation\n\nFigure 4.4 shows these three steps, for encoding for a threshold. As it is obvious significance map generation is the first one performed. After it has been completed, the two remaining steps, assignment of codes and successive approximation quantization iterate to encode all the coefficients for the given threshold.\n\n### 4.4.1 Significance Map Generation\n\n\n\nFigure 4.5 Significance map generation of the memory bank\nShowing direction of processing\n\n---\n\nKarma Wangdi \nSignificance map generation is the first thing that we do in encoding the coefficients. By performing this process we collect information about the significance of the descendents of each coefficient. This information is used when codes are assigned to the coefficients.\n\nWe start from the bottom of the memory bank and move our way up as shown in figure 4.5. The child pointer is made to point to the last coefficient \\((m - 1)th\\) coefficient, that is, the child pointer contains the value \\(m-1\\). The parent pointer is made to point to the last parent, which is the parent of the coefficient that the child pointer is pointing at. The last parent is the last coefficient of the first one-fourth of all the coefficients in the tree. Therefore\n\n\\[ i = (m/4) - 1 = \\text{index of the last parent}. \\]\n\nWith the parent pointer pointing at the last parent in the tree and the child pointer pointing at its last of the four children we do the following:\n\nThe absolute value of the coefficient pointed to the child pointer is compared to the threshold. If \\(|\\text{Coeff}| \\geq T\\), i.e. significant then a ‘1’ is written in the DSig field of the parent coefficient. Since the descendent significance for that parent coefficient is determined there is no need to check for the significance of other three children. So we move to the next parent by decrementing the parent pointer by one.\n\nFor \\(i\\) in 0 to 3 loop\n If abs MemBank(child + i).Coeff ≥ T then\n MemBank(parent).DSig := '1';\n EYcano := '1';\n Exit;\n End If;\nEnd loop;\nIf EYcano = '0' then\n MemBank(parent).DSig := '0';\nend if;\nparent := parent - 1;\nchild := child - 4;\n\nThe child pointer is decremented by 4 to point to the last child of the new parent. We are assuming that we are dealing with parent coefficients that have only one level of descendents, i.e. they only have children. This means that the children themselves do not have children in their turn or they are the leaves of the tree. For parent coefficients with only one level of children\n\n\\[ \\text{DSig}_{\\text{parent}} = \\text{Significance}(\\text{child1 OR child2 OR child3 OR child4}) \\]\nIn this case a possible pseudo-code would look like:\n\nIf the child coefficient is found to be insignificant, the significance of the next child and the other children is checked until we find a significant child. When all the four children are checked and if all of them are found to be insignificant, a '0' is written in the DSig field of the parent coefficient. This is repeated for all the parents that have only one level of descendents.\n\nWhen we reach higher level of parents, that is coefficients that have more than one level of descendents, their DSig field is determined by the significance of both levels of descendents. In other words, the DSig of the parent is determined by the DSig fields and as well as the significance of all its four children. As a result we need to check both the DSig fields and the children coefficients.\n\nIf we find either DSig field containing '1' or the coefficient to be significant for any one of its four children a '1' is written in the DSig field of the parent coefficient. We then proceed to determine the descendent significance of the next parent by decrementing the parent pointer by 1 and the child pointer by 4.\n\nIf DSig field of all the four children contain a '0' and if all the children are insignificant (the absolute values of all the children are less than the threshold T), then a '0' is written in the DSig field of the parent coefficient and we proceed to determine the DSig field for the next parent. For parent coefficients with more than one level of children\n\n\\[\n\\text{DSig}_{\\text{parent}} = \\text{DSig}(\\text{child}_1 \\text{ OR child}_2 \\text{ OR child}_3 \\text{ OR child}_4) \\text{ OR Significance}(\\text{child}_1 \\text{ OR child}_2 \\text{ OR child}_3 \\text{ OR child}_4)\n\\]\n\nIn this way we continue to determine the DSig of the coefficients till we determine the DSig of the main parent. We must remember that the main parent has only three children, so the child pointer must be decremented by 3 when we move to the main\n\n```\nFor i in 0 to 3 loop\n If (Membnk(child + i).Coeff > T OR Membnk(child + i).DSig = '1') then\n Membnk(parent).DSig = '1'; -- Memnk is memory bank\n Membnk(parent).DSig = '1'; -- child is child pointer to the last child\n parent := parent - 1; -- was the loop ended or not\n Exit;\n End if;\nEnd loop;\n```\nparent, instead of decremented by 4 as was the case with other parents.\nThe pseudo-code we could do something like this:\n\nWe realize that there is a need for us to differentiate between the leaves and the higher level coefficients. To this effect the DSig fields of all the coefficients are initialized to 'u' (unknown) prior to significance map generation. So before we check the significance of the child we check if the DSig field of the child contains a 'u'. If it does, then it is a leaf coefficient. The DSig fields of parents get written with '0' or '1' before they are pointed to by the child pointer. So if the DSig of child coefficient does not contain a 'u' then it is not a leaf.\n\nAt this point the memory bank contains enough information so that we can start assigning codes to the coefficients.\n\nThe Flow chart for determining the DSig field of a parent coefficient is shown in Figure 4.5.1.\n\n\n4.4.2 Assignment of Codes\n\nOnce the significance map generation is completed for a given threshold the memory bank contains all the information required for the assignment of codes to begin for that threshold.\n\nAs discussed in chapter 4 four different codes are assigned. Once again, they are:\n\n- ZTR, for zerotree root\n- POS, for positive significant\n- NEG, for negative significant, and\n- IZ, for isolated zero\n\nTo assign the codes we start from the main parent and move downwards as figure 4.6 shows. Here too we use our child pointer and the parent pointer. While the parent pointer points to the parent, the child pointer points to the first child of the four children (three in case of the main parent)\n\nWe use an array to store the codes for the coefficients and information about the approximate values in case of significant codes. This is the array that will contain the embedded codes for the coefficients of the memory bank at the end of the encoding process. In other words this is the array that will contain the result of the encoding.\nThe coefficient that is pointed to by the parent pointer is the one that is assigned code to. To code a coefficient its absolute value is compared to the threshold.\n\nIf the coefficient is significant, it sign is determined by comparing it with zero. If it found to be positive, a POS is stored in the output array and the array index is incremented by one. If it is found to be negative significant, a NEG code is stored in the output array and the array index is incremented by one. Whenever a POS or a NEG is coded, a ‘1’ is written in the Encoded field of the coefficient, to indicate the coefficient has been coded as significant so that future coding of this coefficient does not take place. A pseudo-code for coding significant code is:\n\n\\[\n\\begin{align*}\n\\text{if parent.coeff < 0 then} & \\quad \\text{-- parent is the element pointed to by the parent pointer} \\\\\n\\text{CodeRA(n) := NEG;} & \\quad \\text{-- CodeRA is the array to where we store the codes} \\\\\n\\text{else} & \\quad \\text{CodeRA(n) := POS;} \\\\\n\\text{end if;} & \\\\\n\\text{n := n+1;} & \\quad \\text{-- perform successive approx} \\\\\n\\text{parent.Encoded := '1';} & \\\\\n\\text{parent.coeff := 0;}\n\\end{align*}\n\\]\n\nThe assignment of a significant code is followed by successive approximation, which is discussed in the next section. After successive approximation is completed the coefficient is replaced by a zero. We then move to assign code for the next coefficient by incrementing the parent pointer by 1 and incrementing the child pointer by 4 (3 when the parent being incremented is the main parent).\n\nIf the coefficient is found to be insignificant for the threshold at hand we proceed to find out if it is a zerotree root or (ZTR) or an isolated zero (IZ). This is the time when our significance map proves useful. At this point go back to the significance map and check the DSig field of the parent coefficient. Any of the three conditions would be satisfied.\n\n1. If the DSig field contains a ‘1’ it means that at least one of its descendents is significant, so it is an isolated zero. Subsequently an isolated zero code (IZ) is stored in the output array and the array is incremented by one. We then proceed to determine the code for the next coefficient by incrementing the parent pointer by one and the child pointer by 4 (3 when the parent being incremented to is the first parent).\nb. If DSig field contains a '0' instead of a '1', it means that none of its descendents is significant. So the coefficient is a zerotree root (ZTR). Therefore a ZTR code is stored in the output array and the array is incremented by one. A '1' is then written in the ZTF fields of all the four/three children of the parent coefficient.\n\n\\[ ZTF_{\\text{child}} = ZTF_{\\text{parent}} \\]\n\nIn this way the ZTF information gets passed onto from parents to their children which in turn gets passed to children of the children until it reaches the leaves. This information is used to make sure that we do not code the descendents of ZTR as they are all insignificant and need not be coded.\n\nc. If the DSig field contains a 'u' then it is a leaf. A leaf insignificant is also coded as a ZTR. When decoding we can easily distinguish a leaf coefficient from other coefficients.\n\nA pseudo-code for encoding an insignificant coefficient is:\n\n```\n(when insignificant)\nIf parent.DSig = '1' then -- parent is the element pointed to by the parent pointer\n CodeRA(n) := Z;\nElseIf parent.DSig = '0' then\n CodeRA(n) := ZTR;\n Children.ZTF := '1'; -- for all the children\nElse\n CodeRA(n) := ZTR;\nEnd If;\nEnd If;\n```\n\nThere are two things we need check before we begin to assign code to a coefficient.\n\nThe first one is that we should not code a coefficient that has already been coded as significant. The Encoded field is used for this purpose. As we saw above, a '1' is written in the Encoded field of the coefficient that has been coded as significant. Once written this information is preserved for the rest of the encoding process. So before going on to determine the code for a coefficient its encoded field is checked. Only if a '0' is found in\nthis field we proceed with the next step of assigning code to the coefficient. Otherwise we go to determine the code for the next coefficient.\n\nThe second thing is to check the ZTF field. If a '1' is found in the ZTF field of the coefficient then it is a descendent of a ZTR, so it need not be coded. Only if a '0' is found in the ZTF field of the coefficient do we proceed with determining the code for the coefficient at hand.\n\nSo we don't code a coefficient if either of the ZTF and Encoded fields contains a '1'.\n\nIf the main parent is found to be a zerotree root then all other coefficients are insignificant for the threshold at hand and there is no need to code any further for that threshold. We then proceed to encode for the next lower threshold.\n\nIn this manner we assign codes to coefficients in the memory bank for a given threshold.\n\nThe flow chart for assigning a to a coefficient is shown in figure 3.8 in the last chapter.\n\n4.4.3 Successive Approximation Quantization\n\nSuccessive approximation quantization is the process by which information on the values of the coefficients is embedded with the codes instead of passing the whole coefficient itself. When we have finished discussing this topic we can appreciate how the precision of the coefficient values are improved with each threshold level codes. If the decoder is provided with all the codes then it can reconstruct the exact coefficient values. Otherwise it will only be able to reconstruct an approximate value of the coefficient depending on the number of the codes it receives. Let's see how this happens.\n\nGiven the size of the tree it is possible to tell against which threshold a code has been coded. That is given a code, say POS, we can tell whether it has been positive significant against 64 or 32 or 16 or other threshold values. This information is implicitly contained in the encoded codes.\nFigure 4.7 Coefficients and their reconstructed values from knowing the thresholds\n\nWith the thresholds we use, 64, 32, 16, 8, 4, 2, and 1, and using the centre of the uncertainty interval as the reconstruction value the coefficients can be reconstructed as shown in figure 4.7\n\nIn order to be able to reconstruct the exact original coefficients from the codes the knowledge of threshold itself isn't enough. So we need to send additional information on the coefficient value with the codes. This is what successive approximation quantization exactly does.\n\nWhenever a POS or NEG is coded during the assignment of codes we subtract the threshold value from the absolute value of the coefficient. We then store the value of the remainder in the two dimensional array and send the information on this remainder to\n\nBits and the values they indicate\n\nFigure 4.8 The two dimensional array for storing information on the coefficient values\n\n7 bits for each coefficient\nthe decoder. Since the maximum absolute value of a coefficient can be 128 and since the max threshold is 64 we can have a maximum remainder of 64 (128 - 64). As a result we use 7 bits for each coefficient. So the two dimensional array becomes \\( m-1 \\times 7 \\) of bits as shown in figure 4.8. In figure 4.8 the codes are numbered and these codes are the significant codes (POS or NEG) number. The numbering is such that code number 0 is the first significant code encoded, code 1 the second one and so on.\n\nFurther explanation can be more effectively achieved by taking an example.\n\nLet us say that we started our encoding with threshold 64 and got a POS as the first significant code. Let us further assume that this coefficient has a value of 120. As soon as we code this POS we build the additional information. The remainder is (120 - 64 = 56). This 56 can be broken down into (56 = 32 + 16 + 8). Because it is the first significant code we store this information in the first row of the 2 dimensional array. We write a '0' in the bit places corresponding to 64, 4, 2 and 1 and write a '1' in the bit places corresponding to values 32, 16 and 8. After this the two dimensional array looks like shown in figure 4.9.\n\n\n\nSince our threshold is 64 and a remainder of 64 is possible we store the bit information contained in the bit place corresponding 64 right after the code in the output code array. Here right after we store POS, '0' is stored in the output array.\n\nLet us assume that our next significant code is a NEG and assume that the coefficient is -85. Obviously this is also against threshold 64. So the remainder of the coefficient for which we need to provide additional information is (85 - 64 = 21). 21 can be written as\n(16 + 4 + 1). Since this is the second significant code we store the information in the seven bit positions of the second row in the two dimensional array. A '1' is written in the bit positions corresponding to the values 16, 4 and 1 and a '0' is written in other bit positions. Similarly right after the code NEG, we store a '0', for 64, in the output code array since the threshold is still 64 and a remainder of 64 is possible.\n\nNow let us say that our third significant code is a POS and the coefficient is value 47. Obviously the threshold is 32, since it is less than 64 and greater than or equal to 32. The remainder is (47-32 = 15). 15 can be written as (8 + 4 + 2 + 1). Like before we store this information in the third row of the 2 dimensional array, storing '1' in the bit positions corresponding to 8, 4, 2, and 1 and '0' in bit position corresponding to 16. Since the threshold here is 32 when we subtract 32 from lcoefficientl the maximum remainder that we will get is 31. This is because when encoding has been finished for threshold 64, the maximum absolute value of the unencoded coefficients will be 63. Otherwise it will have been significant against threshold 64 and coded as significant earlier. So we do not need to write anything in the bit positions corresponding to 64 and 32 in the 2 dimensional array.\n\n<table>\n<thead>\n<tr>\n<th>Bits and the values they indicate</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n</tr>\n<tr>\n<td>---</td>\n</tr>\n<tr>\n<td>0</td>\n</tr>\n<tr>\n<td>1</td>\n</tr>\n<tr>\n<td>2</td>\n</tr>\n<tr>\n<td></td>\n</tr>\n<tr>\n<td></td>\n</tr>\n<tr>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nFigure 4.10 The two dimensional array with information for the third significant code\n\nFor threshold less than 64 the maximum lcoefficientl is 2T−1; T being the threshold. The maximum remainder is (2T−1)−T = T−1. So we do not have bit information corresponding to values >= T. Hence we do not need to write anything in those bit positions of the 2 dimensional array. Also we do not need to provide information on the approximate values in these bit positions. Figure 4.10 shows our 2 dimensional array after successive approximation quantization of this third significant has been completed.\nThere is an additional thing that we do when we code the first significant for lower thresholds than 64. Right after the code is stored in the output code array the bit information in the two dimensional array corresponding to the current threshold value for all the significant codes encoded for higher threshold values are stored in the output code array. In our example when we store the third code (POS for 47) it is the first significant code for 32. So after storing the code we look at the bit positions corresponding to the value 32 in the 2 dimensional array for already coded coefficients for 64 (row 0 and 1). Referring to our two dimensional array in figure 4.8 we find a '1' for row 0 and '0' for row 1. So we store these bit information in the output code array right after the POS code is stored. For the other codes, for the same threshold 32 we only need to store the code and do not need to send any information on the coefficient values. However we still have to fill the two dimensional array for the code with the additional information for the coefficient value to be sent when lower level thresholds are encoded.\n\nAt this point, the output code array according to our example would look like the one shown in figure 4.11\n\nTo generalize, whenever we code the first significant for a threshold (less than 64) we send the bit information on that threshold for all the codes that have been coded significant against higher thresholds. That is, when we code for the first significant for threshold 16 we store the code in the output array and then store all the bits\ncorresponding to value 16 in the 2 dimensional array for all the significant codes that have been coded for 64 and 32. Similarly when we code the first significant for threshold 8, we store the code and then store all the bit information corresponding to value 8 in the 2 dimensional array for all previously coded significant codes for 16, 32 and 64.\n\nSimilarly we code for the rest of the thresholds.\n\nWe observe that with each lower level of threshold more precision information is added as we code for each lower level threshold. Finally when we have coded for the last threshold 1, the output array has enough information so that the decoder can be able to reconstruct the original coefficient.\n\nAt this point the encoding is completed.\n\n4.4.4 Updating the DSig, ZTF, Encoded and Coeff fields\n\nThe DSig fields are initialized to 'u' before significance map generation starts. That is it is initialized to 'u' at the start of coding for every threshold.\n\nThe ZTF fields are also initialized to '0' at the beginning of coding for every threshold.\n\nThe Encoded field is initialized only once, at the beginning of the encoding process, to '0'. Once set it remains set for the remainder of the encoding process.\n\nThe Coeff field is set to 0 once the coefficient has been coded as significant. This prevents the significant coefficient from preventing the occurrence of zerotree roots.\n\n4.4.5 Summary\n\nEncoding is achieved through three operations: significance map generation, assignment of codes and successive approximation.\nStarting with threshold 64 we first generate the significance map. Then we assign codes and perform successive approximations as required for each coefficient and repeat code generation and successive approximation till we have coded for the last coefficient in the memory bank. Encoding is completed for threshold 64.\n\nWe then code for the next lower threshold (here 32) by repeating the above process, then for 16, then for 8, then 4, then 2, and finally with 1.\n\nThis way when the last threshold has been coded for, the encoding is complete. We get in our output array the codes and the information on the coefficient values as the result of encoding.\nB. Decoder Design\n\n4.5 Introduction\nAt the end of the decoding we will obtain the same number of coefficients that has originally been encoded, and in the same order as we found them before encoding in part A.\n\n4.6 Assumption on Codes\nWe assume that the codes to be decoded are stored in an array, like the result of the encoding described in part A. In practical application the codes can be reaching the decoder one after another in real time, with the most significant codes (those coded for higher thresholds) first followed by the less significant ones. To repeat what have been already said in chapter 3, codes that are coded for higher threshold values are considered more significant than those coded for lesser threshold values. With our array assumption, the most significant codes are stored in the beginning followed by less significant ones. For the purpose of explanation we call this array the code array.\n\n4.7 Architecture\nIn the decoder too we use a record of four fields to store vital information. The fields are Coeff field, ZTF field, Decoded field and the Sign field. The Coeff field is used to store the decoded coefficient while the other three are used to store information about the coefficient to facilitate the decoding process. Since the size of the tree was \\( m \\), we use an array of size \\( m \\) (from 0 to \\( m-1 \\)) of the four-field record. The array of record is shown in figure 4.12.\n\nThe four fields and their meanings are:\n\n- Coeff: The Coeff field is used to store the decoded coefficient\n\n- ZTF: The ZTF field is used to store binary information to indicate whether a zerotree root has already been found. A '1' in the field is to indicate that the coefficient is an\nelement of a zerotree. That is, an ancestor of it has been found to be a zerotree root. A '0' indicates otherwise.\n\n- **Decoded**: The Decoded field is used to store binary information to indicate whether or not the coefficient has been decoded already. A '1' means 'yes' while a '0' means 'no'.\n\n- **Sign**: The Sign field is used to store the sign of the coefficient. '1' indicates that the sign is negative while '0' indicates that it is negative.\n\n<table>\n<thead>\n<tr>\n<th>Array indices</th>\n<th>Coef</th>\n<th>ZTF</th>\n<th>Decoded</th>\n<th>Sign</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>1</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>2</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>3</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>4</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>...</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>m-1</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nFigure 4.12: Array of record fields, used for decoding\n\nAs in the encoder, here too we make use of two pointers: a parent pointer and a child pointer. We also use an array to store the indices of the coefficients that have already\n\n\nbeen decoded. A counter is also used to store the number of codes that have been decoded. A diagrammatic representation of the decoder as a whole is shown in figure 4.13.\n\n4.8 Decoding Process\n\nThe decoding is dictated by the encoding. As such it is a matter of how elegantly the reverse of encoding can be performed. The following paragraphs shows how we achieve this.\n\n4.8.1 Preparation\n\nAt the beginning of the decoding process all the four fields of the record array are initialized. The Coeff field is given a value 0 and the ZTF, Decoded and Sign fields are all set to '0'.\n\nSince the record array is to contain the coefficients in the exact order as they were before encoding, the same parent-child relationship holds between indices of the array in which the decoded coefficients will be stored. That is, in the record array, the Coeff field of index 0 will contain the main parent, Coeff field of indices 1, 2, and 3 will contain the three children of the main parent, and Coeff field of indices 4, 5, 6 and 7 will contain the four children of coefficient in index 1, and so on.\n\nThe parent pointer is made to point to the main parent and the child pointer is made to point to the first child of the main parent.\n\nParent Pointer = 0;\nChild Pointer = 1;\n\nThe decoding is done for the coefficient pointed to by the parent pointer. We start from the main parent and move downward through to the bottom of the record array. First we decode for the highest threshold, 64, then for 32, then for 18 and so on. For each threshold the following steps are involved.\n4.8.2 Checking the ZTF and Decoded Fields\n\nBefore we read the code from the code array to decode, we check the Decoded and the ZTF fields of the parent (index pointed to by the parent pointer) of the record array which will contain the decoded coefficients. The flow chart for performing this check is shown in figure 4.13.1\n\nIf the Decoded field contains '1' it means that the coefficient has already been decoded for. So we move to the next parent by incrementing the parent pointer by one and the child pointer by four (three if the current parent is the main parent). If the Decoded field contains a '0' instead then we check for the ZTF field.\n\n\n\nIf the ZTF field contains a '1', it means that it is an element of a zerotree root found earlier, so we do not have to decode for this coefficient as there is no code for this coefficient for the current threshold. The zerotree found ahead message is then passed onto its children by writing '1' in the ZTF field of all its children. We then move to the next coefficient by incrementing the parent pointer by one and the child pointer by four (three if the current parent is the main parent). The checking operation could translate into the a possible pseudo-code:\n\nIf parent.Decoded = '1' then\n parent pointer := parent pointer + 1;\n child pointer := child pointer + 4 (or 3);\nElse\n If parent.ZTF = '1' then\n For i in 0 to 3 (or 2) loop\n child(i).ZTF := '1'; -- the child pointer gives the index of the first child\n End Loop;\n -- child(0) is the first child child(i) is the second child and so on\n End If;\n parent pointer := parent pointer + 1;\n child pointer := child pointer + 4 (or 3);\nElse\n -- Read the code ...\nEnd If;\nEnd If;\n-- repeat the process\n\n4.8.3 Deciphering the Code and Reconstructing the Coefficients\n\nIf both the Decoded field and the ZTF field are found to contain '0' then the code that is about to be read from the code array is for the coefficient pointed to by the parent pointer. So the code is read from the code array and decoded.\n\nThe flow chart for deciphering a code and reconstructing the coefficients is shown in figure 4.13.2\nThe code can be any of the four different codes: NEG, POS, IZ and ZTR. We process each of them as follows:\n\na. If the code is a ZTR there are three cases that can arise.\n\nIf the parent pointer is pointing to the main parent, the rest of the coefficients are insignificant against the current threshold. There are no codes for them in the code array for the current threshold. So we move to decode for the next threshold level. And start again from the main parent by setting the child pointer and the parent pointer are set as\n\n\\[\n\\text{parent pointer} := 0; \\\\\n\\text{child pointer} := '1';\n\\]\n\nand start the process all over again, but for the next level of threshold value. Actually the parent and child pointers are unchanged. For example if threshold that we found the main parent as the ZTR was 64, the next threshold is 32.\n\nIf the parent pointer neither points to the main parent or to a leaf coefficient, then the ZTF fields of its four children are set to '1', and we move to decode for the next coefficient by incrementing the parent pointer by 1 and the child pointer by four.\n\nAn equivalent pseudo-code code would be:\n\n(When code is ZTR)\n\n\\begin{verbatim}\nif parent = main parent then\n -- change to the next threshold\n -- read the next code\nelsif parent = leaf then\n for i in 0 to 3 loop\n child(i).ZTF := '1';\n end loop;\n child pointer := child pointer + 4;\n parent pointer := parent pointer + 1;\nelse\n -- leaf coefficient\n parent pointer := parent pointer + 1;\nend if;\n\n-- decode for the next coefficient\n\\end{verbatim}\n\nIf the parent pointer points to the leaf coefficients we do not need to do anything. We increment the parent pointer by 1 and go to decode for the next coefficient. Note that we do not increment the child pointer because the coefficient pointed to by the parent pointer does not have any child as it is a leaf coefficient itself.\nb. If the code is an isolated zero (IZ) the coefficient is insignificant, so we move to decode for the next coefficient by incrementing the parent pointer by 1 and the child pointer by 4 (or 3 if the current parent is the main parent).\n\nc. If the code is a POS, the coefficient is significant with respect to the current threshold. This means that the absolute value of the coefficient had been greater than or equal to the current threshold. So we add the threshold value to the value contained in the Coeff field (Coeff := Threshold). We then set the Decoded field to ‘1’ to indicate that the coefficient has been decoded. Another thing that we do here is to store the array index of this decoded coefficient in the index array that is indicated in figure 4.13.\n\nTo repeat, the index array is used to store the array indices of the decoded coefficients. The indices are stored in order, first the index of the coefficient that was decoded first, then that of the second, then that of the third and so on. The contents of this index array serve as pointers to the coefficients when we decode for lower thresholds to construct more precise coefficients that are decoded for higher thresholds. Since we have initialized the sign fields to ‘0’ which indicates a positive coefficient we do not need to set the sign field.\n\nIf the current threshold is 64 then the next code in the code array is the precision information for decoded coefficient. It is read, and if a ‘1’ is found a precision of 64 (Coeff := Coeff + 64) is added to the coefficient, and no precision is added if a ‘0’ is found.\n\nIf the threshold is lower than 64 (i.e., 32, 16, 8, 4, 2, and 1), and if the coefficient decoded is the first for the threshold, then the codes in the code array after the currently decoded POS are not codes but information on the precision of the coefficients that have been decoded before. There are as many bits following the currently decoded code as the number of already decoded coefficients. The number of decoded coefficients is contained in the counter. The first bit information is for the first decoded coefficient, the second bit information for the second decoded coefficient and the third bit for the third decoded coefficient and so on. A ‘1’ means that the corresponding coefficient has an additional precision value of T.\n(current threshold) so \\( T \\) is added to it. A '0' means that the corresponding coefficient does not have additional \\( T \\) precision, so we do not add \\( T \\) to it. The information for the number of bit information to be read is given by the counter, while the pointers to the decoded coefficients are given by the index array.\n\nAn equivalent pseudo-code for this would be:\n\n```\n( When POS)\nparent.Coeff := T; -- T is the threshold\nIf T = 64 then\n Read the next code (bit information) from the code array\n If bit info read = '1' then\n parent.Coeff := parent.Coeff + 64;\n Else\n Null;\nElse Coefficient decoded = the first for the threshold then\n add precision (by \\( T \\)) to the other already decoded coefficients\nElse\n Null;\nEnd If;\nparent pointer := parent pointer + 1;\nchild pointer := child pointer + 4; (if parent is not a leaf)\n```\n\nd. If the code is a NEG, it is also a significant coefficient so we do exactly the same things that we do when the code is POS, except for the sign field. A '1' is stored in the Sign field to indicate that the sign is negative.\n\nIn this way we first decode for \\( T = 64 \\) then for \\( T = 32 \\), then 16, then 8 and so on until we have decoded for 1. Note how precision is added with the decoding for each lower threshold. When we have finished for threshold = 1 we will have got exactly the same coefficients (in the Coeff field of the record array) and in the same order as they were before they were encoded.\n\nIn above we have not discussed the issue of bit truncation. If the bitstream is truncated we need to add additional precision value to all the decoded coefficients. How much to be added depends on where the truncation occurs.\n\nFor example, if the current threshold is 32 and the last code obtained is a POS and this POS is not the first significant coefficient for the current threshold (32), it may or may not have an additional \\( (64-32) = 32 \\). So the uncertainty of 16 is added to it. So it is reconstructed to 48 \\( (32 + 16) \\). All the previously encoded coefficients are also given an additional value of 16.\nIf this POS is the first significant for the current threshold it is itself given an additional value of 16 (center of uncertainty). For those decoded before it, the uncertainty is the center of 64 and 128, so 32 is the center of uncertainty. As such all those coefficients are added by 32.\n\nTo generalize when truncation occurs, the centre of uncertainty is added to the already decoded coefficients.\n\nThis completes the decoding.\n\n**4.8.4 Updating the Decoded, ZTF, Coeff and Sign Fields**\n\nThe Decoded field is initialized to '0' only once in the whole decoding process. That is done at the start of the decoding. Once set it remains set throughout the process. The ZTF field is set to '0' at the start of every new threshold value. This is because a ZTF set to '1' is relevant only for the threshold that it was set.\n\nThe Sign field is set to '0' in the beginning to indicate positive. It is set to '1' when a negative coefficient is decoded, and it remains set throughout.\n\nThe Coeff field is set to 0 at the start. As the decoding happens it gets filled in with the real coefficients.\nC. Parallel Processor Architecture\n\n4.9 Introduction\n\nThis architecture is not a completely different architecture to what we have discussed above. In fact it is only a slight adaptation of the single processor architecture, trying to make use of the advantage of inherent parallelism present in the zerotree of wavelet coefficients. A faster codec is thus envisaged from using this architecture. Bae and Prasana also propose this architecture.\n\n4.10 Observation of Inherent Parallelism\n\nIf we look at the parent-child dependencies of the subbands in a zerotree we realize that there are three main branches, with the main ancestor common to all three of them. They are shown in figure 4.14 as branch_A, branch_B and branch_C. These three branches are each independent of the other, while the way in which coefficients within one branch relate among themselves is the same as the way in which the coefficients in another branch relate among themselves. This then points to us that if we have three separate but same processors we can process the entire tree using three such processors in parallel, each processor handling a main branch. This translates to a processor having to handle only one third of the coefficients it would have had to handle otherwise, thus promising a speedier codec. We can make use of this inherent parallelism in the design of the codec.\n\n\n4.11 Architecture\n\nThe coefficients in each of the three branches are mapped into three memory banks as shown in the figure 4.15. The first coefficient of a branch is mapped into the element 0 of the memory bank, the 2nd coefficient is mapped into element 1, the 3rd into element 2 of the memory bank, and so on until the last coefficient is mapped into the last element of the memory bank. The main parent is mapped as the first coefficient in each of the three memory banks. So the first coefficient is the same for all the three memory banks.\n\nEach memory bank contains one third of the total number of coefficients in the tree.\n\nHaving mapped the coefficients into the three memory banks each of the memory banks is encoded and decoded as exactly same as that for single processor encoder and decoder in part A and B above. And each of them can be processed in parallel by three identical processors.\nSince the encoding and decoding strategies used are the same as in the single processor architecture they will not be discussed here again as it would just be unnecessary repetition. Instead the difference will be pointed out.\n\nThere is one important difference to note here. This happens in the encoder. When we have finished generating the significance map for a given threshold. The DSig value of the main ancestor (the first coefficient) as determined in a memory bank is not its true value. Being the main ancestor of all the three memory banks in three separate encoders, its descendant significance can be determined only after having information of its descendents in all the three memory banks. However the DSig field of the main ancestor in a memory bank contains all the information required from that memory bank, to determine the exact descendant significance of the main ancestor. If we can get together the DSig information for the main parent (first coefficient) from each of the memory banks then we will be able to determine the true DSig value of the main parent. The encoding can not proceed until the true DSig value is determined and passed to the three processors.\n\nThis is what we do. We have two other processes working on the other two memory banks in parallel. The content of the DSig field of the main ancestor in each memory bank is sent to a different processor (we call it DSig process here) to determine the exact descendant significance of the main ancestor. The actual descendant significance of the main ancestor is ‘0’ only if all the DSig value from all the three encoder is ‘0’. If either one of them is a ‘1’ then the DSig of the main ancestor is a ‘1’. In the processor where this actual DSig of the main ancestor is determined, the three DSig field values from three parallel encoders are ORed.\n\n\\[ \\text{True DSig main parent} = \\text{DSig main parent (A)} \\text{ OR DSig main parent (B)} \\text{ OR DSig main parent (C)} \\]\n\nThe result is the true descendant significance of the main ancestor for the particular threshold. This information is passed back to the three parallel encoders/processors. Once the true DSig value of the main parent is received, the next stage of assigning codes can begin. After sending the DSig value of the main parent as determined from the coefficients in a given memory bank to the DSig process, the processing is halted till it gets the true DSig value of of the main parent from the DSig process. The data\ntransmission employs a simple handshaking mechanism. Figure 4.16 shows how these four processors relate.\n\nBesides this difference the encoding and decoding using the three parallel processors is the same as was described in the case of the single processor architecture. The obvious difference here is that instead of having to process (encode or decode) the whole tree the processors here process only a third of the coefficients. And owing to the nature of the EZW algorithm this parallel processing should give a very fast codec. At least three times as fast as the first one.\n\nAnother difference is that the first coefficient in each memory bank has just one child coefficient.\n\nDecoding is exactly the same as the single processor except for the main parent having only one child in each memory bank. There is no communication needed between the decoders.\nTo conclude this chapter diagrammatic representation of the single processor architecture and the parallel processor codec are presented.\n\n**Figure 4.17** Single processor codec\n\n**Figure 4.18** The Parallel architecture codec\n5. SIMULATION AND SYNTHESIS\n\nA. Simulation\n\n5.1 Introduction\n\nThe VHDL coding was done at the behavioral level and the programs were simulated. Both the single processor codec and the codec with three parallel processors were simulated and results were verified.\n\nWith the parallel processor codec, the coefficients were input into the encoder and the resulting codes were fed into the corresponding decoder. It was checked if it gave the same coefficients as those input into the encoder.\n\nWith the single processor codec extensive tests were performed. It was not only checked to see if the decoder reconstructed the same coefficients in the same order as that was input into the encoder, it was also checked to see how it produced more and more precise coefficients when the first number of codes given were increased.\n\nAll the tests were checked against those computed by hand, and it was found that the codec of both architectures, parallel processor and single processor, were working correctly as expected.\n\n5.2 Test Data\n\nThe test data used was a standard data obtained from Shapiro’s original paper for 8 x 8 coefficient. So the design was checked for 8 x 8 coefficients. There was another reason why this data set was chosen.\n\nIn keeping with the specification of the project, to assume static input data, data as contained in a memory bank in the required order, the interface was not designed as it would have hugely side tracked the project work. As a result inputs were written into the array elements by hand in the program. What this translated to was an enormous\nnumber of inputs to be written by hand within the code. Just for an 8 x 8 coefficients the number of codes obtained was about 300, which is almost 5 times the number of coefficients. All these 300 codes had to be input by hand inside the code to check for the decoder. If a 64 x 64 coefficients were tested, assuming a linear relationship between the number of coefficients (in reality the number of codes obtained would be more than that obtained from this assumption), there would be 4096 inputs for the encoder and 20,480 codes to be input into the decoder, all by hand. These numbers are truly prohibitively large. Even for a 16 x 16 coefficients, the codes would number more than 1300. As a result tests were performed using the 8 x 8 coefficients data.\n\nBut we should remember that the codec designed was a generic one. So the argument is if it works for an 8 x 8 coefficients it should also work for any image\nsize. In fact had there been sufficient time to do the interface design this claim would have been proved indeed.\n\nThe standard test data is shown below.\n\n5.3 Simulation Result for Single Processor Codec\n\nThe results presented below were all checked against hand worked results, and it was found both results tallied as desired.\n\n5.3.1 Encoder Simulation\n\nInput = from figure 5.1, Output code = Table 5.0\n\n<table>\n<thead>\n<tr>\n<th>ZTR</th>\n<th>ZTR</th>\n<th>POS</th>\n<th>ZTR</th>\n<th>POS</th>\n<th>ZTR</th>\n<th>NO</th>\n<th>NEG</th>\n<th>YES</th>\n<th>NO</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>POS</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>NO</td>\n<td>POS</td>\n<td>NO</td>\n</tr>\n<tr>\n<td>NEG</td>\n<td>ZTR</td>\n<td>POS</td>\n<td>ZTR</td>\n<td>POS</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>YES</td>\n<td>POS</td>\n<td>YES</td>\n</tr>\n<tr>\n<td>YES</td>\n<td>NO</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>POS</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>YES</td>\n<td>POS</td>\n<td>NO</td>\n</tr>\n<tr>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>POS</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>NO</td>\n<td>YES</td>\n</tr>\n<tr>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>POS</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>NO</td>\n<td>YES</td>\n</tr>\n<tr>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>POS</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>NO</td>\n<td>YES</td>\n</tr>\n<tr>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>POS</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>ZTR</td>\n<td>NO</td>\n<td>YES</td>\n</tr>\n</tbody>\n</table>\n\nTable 5.0 Result from encoding (single processor architecture)\n5.3.2 Decoder Simulation\n\n<table>\n<thead>\n<tr>\n<th>Index</th>\n<th>Reconstructed Coefficients</th>\n<th>Index</th>\n<th>Reconstructed Coefficients</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>0</td>\n<td>6</td>\n<td>32</td>\n</tr>\n<tr>\n<td>1</td>\n<td>54</td>\n<td>7</td>\n<td>32</td>\n</tr>\n<tr>\n<td>2</td>\n<td>3</td>\n<td>9</td>\n<td>32</td>\n</tr>\n<tr>\n<td>3</td>\n<td>64</td>\n<td>10</td>\n<td>32</td>\n</tr>\n<tr>\n<td>4</td>\n<td>64</td>\n<td>11</td>\n<td>32</td>\n</tr>\n<tr>\n<td>5</td>\n<td>64</td>\n<td>12</td>\n<td>32</td>\n</tr>\n<tr>\n<td>6</td>\n<td>64</td>\n<td>13</td>\n<td>32</td>\n</tr>\n<tr>\n<td>7</td>\n<td>64</td>\n<td>14</td>\n<td>32</td>\n</tr>\n<tr>\n<td>8</td>\n<td>64</td>\n<td>15</td>\n<td>32</td>\n</tr>\n<tr>\n<td>9</td>\n<td>64</td>\n<td>16</td>\n<td>32</td>\n</tr>\n<tr>\n<td>10</td>\n<td>64</td>\n<td>17</td>\n<td>32</td>\n</tr>\n<tr>\n<td>11</td>\n<td>64</td>\n<td>18</td>\n<td>32</td>\n</tr>\n<tr>\n<td>12</td>\n<td>64</td>\n<td>19</td>\n<td>32</td>\n</tr>\n<tr>\n<td>13</td>\n<td>64</td>\n<td>20</td>\n<td>32</td>\n</tr>\n<tr>\n<td>14</td>\n<td>64</td>\n<td>21</td>\n<td>32</td>\n</tr>\n<tr>\n<td>15</td>\n<td>64</td>\n<td>22</td>\n<td>32</td>\n</tr>\n<tr>\n<td>16</td>\n<td>64</td>\n<td>23</td>\n<td>32</td>\n</tr>\n<tr>\n<td>17</td>\n<td>64</td>\n<td>24</td>\n<td>32</td>\n</tr>\n<tr>\n<td>18</td>\n<td>64</td>\n<td>25</td>\n<td>32</td>\n</tr>\n<tr>\n<td>19</td>\n<td>64</td>\n<td>26</td>\n<td>32</td>\n</tr>\n<tr>\n<td>20</td>\n<td>64</td>\n<td>27</td>\n<td>32</td>\n</tr>\n<tr>\n<td>21</td>\n<td>64</td>\n<td>28</td>\n<td>32</td>\n</tr>\n<tr>\n<td>22</td>\n<td>64</td>\n<td>29</td>\n<td>32</td>\n</tr>\n<tr>\n<td>23</td>\n<td>64</td>\n<td>30</td>\n<td>32</td>\n</tr>\n<tr>\n<td>24</td>\n<td>64</td>\n<td>31</td>\n<td>32</td>\n</tr>\n<tr>\n<td>25</td>\n<td>64</td>\n<td>32</td>\n<td>32</td>\n</tr>\n</tbody>\n</table>\n\nTable 5.1: Reconstructed from first 21 codes\n\n<table>\n<thead>\n<tr>\n<th>Index</th>\n<th>Reconstructed Coefficients</th>\n<th>Index</th>\n<th>Reconstructed Coefficients</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>32</td>\n<td>6</td>\n<td>32</td>\n</tr>\n<tr>\n<td>1</td>\n<td>64</td>\n<td>7</td>\n<td>32</td>\n</tr>\n<tr>\n<td>2</td>\n<td>32</td>\n<td>8</td>\n<td>32</td>\n</tr>\n<tr>\n<td>3</td>\n<td>32</td>\n<td>9</td>\n<td>32</td>\n</tr>\n<tr>\n<td>4</td>\n<td>64</td>\n<td>10</td>\n<td>32</td>\n</tr>\n<tr>\n<td>5</td>\n<td>64</td>\n<td>11</td>\n<td>32</td>\n</tr>\n<tr>\n<td>6</td>\n<td>64</td>\n<td>12</td>\n<td>32</td>\n</tr>\n<tr>\n<td>7</td>\n<td>64</td>\n<td>13</td>\n<td>32</td>\n</tr>\n<tr>\n<td>8</td>\n<td>64</td>\n<td>14</td>\n<td>32</td>\n</tr>\n<tr>\n<td>9</td>\n<td>64</td>\n<td>15</td>\n<td>32</td>\n</tr>\n<tr>\n<td>10</td>\n<td>64</td>\n<td>16</td>\n<td>32</td>\n</tr>\n<tr>\n<td>11</td>\n<td>64</td>\n<td>17</td>\n<td>32</td>\n</tr>\n<tr>\n<td>12</td>\n<td>64</td>\n<td>18</td>\n<td>32</td>\n</tr>\n<tr>\n<td>13</td>\n<td>64</td>\n<td>19</td>\n<td>32</td>\n</tr>\n<tr>\n<td>14</td>\n<td>64</td>\n<td>20</td>\n<td>32</td>\n</tr>\n<tr>\n<td>15</td>\n<td>64</td>\n<td>21</td>\n<td>32</td>\n</tr>\n<tr>\n<td>16</td>\n<td>64</td>\n<td>22</td>\n<td>32</td>\n</tr>\n<tr>\n<td>17</td>\n<td>64</td>\n<td>23</td>\n<td>32</td>\n</tr>\n<tr>\n<td>18</td>\n<td>64</td>\n<td>24</td>\n<td>32</td>\n</tr>\n<tr>\n<td>19</td>\n<td>64</td>\n<td>25</td>\n<td>32</td>\n</tr>\n<tr>\n<td>20</td>\n<td>64</td>\n<td>26</td>\n<td>32</td>\n</tr>\n<tr>\n<td>21</td>\n<td>64</td>\n<td>27</td>\n<td>32</td>\n</tr>\n<tr>\n<td>22</td>\n<td>64</td>\n<td>28</td>\n<td>32</td>\n</tr>\n<tr>\n<td>23</td>\n<td>64</td>\n<td>29</td>\n<td>32</td>\n</tr>\n<tr>\n<td>24</td>\n<td>64</td>\n<td>30</td>\n<td>32</td>\n</tr>\n<tr>\n<td>25</td>\n<td>64</td>\n<td>31</td>\n<td>32</td>\n</tr>\n<tr>\n<td>26</td>\n<td>64</td>\n<td>32</td>\n<td>32</td>\n</tr>\n</tbody>\n</table>\n\nTable 5.2: Reconstructed from first 44 codes\n\n<table>\n<thead>\n<tr>\n<th>Index</th>\n<th>Reconstructed Coefficients</th>\n<th>Index</th>\n<th>Reconstructed Coefficients</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>38</td>\n<td>6</td>\n<td>32</td>\n</tr>\n<tr>\n<td>1</td>\n<td>64</td>\n<td>7</td>\n<td>32</td>\n</tr>\n<tr>\n<td>2</td>\n<td>32</td>\n<td>8</td>\n<td>32</td>\n</tr>\n<tr>\n<td>3</td>\n<td>32</td>\n<td>9</td>\n<td>32</td>\n</tr>\n<tr>\n<td>4</td>\n<td>32</td>\n<td>10</td>\n<td>32</td>\n</tr>\n<tr>\n<td>5</td>\n<td>64</td>\n<td>11</td>\n<td>32</td>\n</tr>\n<tr>\n<td>6</td>\n<td>64</td>\n<td>12</td>\n<td>32</td>\n</tr>\n<tr>\n<td>7</td>\n<td>64</td>\n<td>13</td>\n<td>32</td>\n</tr>\n<tr>\n<td>8</td>\n<td>64</td>\n<td>14</td>\n<td>32</td>\n</tr>\n<tr>\n<td>9</td>\n<td>64</td>\n<td>15</td>\n<td>32</td>\n</tr>\n<tr>\n<td>10</td>\n<td>64</td>\n<td>16</td>\n<td>32</td>\n</tr>\n<tr>\n<td>11</td>\n<td>64</td>\n<td>17</td>\n<td>32</td>\n</tr>\n<tr>\n<td>12</td>\n<td>64</td>\n<td>18</td>\n<td>32</td>\n</tr>\n<tr>\n<td>13</td>\n<td>64</td>\n<td>19</td>\n<td>32</td>\n</tr>\n<tr>\n<td>14</td>\n<td>64</td>\n<td>20</td>\n<td>32</td>\n</tr>\n<tr>\n<td>15</td>\n<td>64</td>\n<td>21</td>\n<td>32</td>\n</tr>\n<tr>\n<td>16</td>\n<td>64</td>\n<td>22</td>\n<td>32</td>\n</tr>\n<tr>\n<td>17</td>\n<td>64</td>\n<td>23</td>\n<td>32</td>\n</tr>\n<tr>\n<td>18</td>\n<td>64</td>\n<td>24</td>\n<td>32</td>\n</tr>\n<tr>\n<td>19</td>\n<td>64</td>\n<td>25</td>\n<td>32</td>\n</tr>\n<tr>\n<td>20</td>\n<td>64</td>\n<td>26</td>\n<td>32</td>\n</tr>\n<tr>\n<td>21</td>\n<td>64</td>\n<td>27</td>\n<td>32</td>\n</tr>\n<tr>\n<td>22</td>\n<td>64</td>\n<td>28</td>\n<td>32</td>\n</tr>\n<tr>\n<td>23</td>\n<td>64</td>\n<td>29</td>\n<td>32</td>\n</tr>\n<tr>\n<td>24</td>\n<td>64</td>\n<td>30</td>\n<td>32</td>\n</tr>\n<tr>\n<td>25</td>\n<td>64</td>\n<td>31</td>\n<td>32</td>\n</tr>\n<tr>\n<td>26</td>\n<td>64</td>\n<td>32</td>\n<td>32</td>\n</tr>\n</tbody>\n</table>\n\nTable 5.3: Reconstructed from first 100 codes\n\n<table>\n<thead>\n<tr>\n<th>Index</th>\n<th>Reconstructed Coefficients</th>\n<th>Index</th>\n<th>Reconstructed Coefficients</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>38</td>\n<td>6</td>\n<td>32</td>\n</tr>\n<tr>\n<td>1</td>\n<td>64</td>\n<td>7</td>\n<td>32</td>\n</tr>\n<tr>\n<td>2</td>\n<td>32</td>\n<td>8</td>\n<td>32</td>\n</tr>\n<tr>\n<td>3</td>\n<td>32</td>\n<td>9</td>\n<td>32</td>\n</tr>\n<tr>\n<td>4</td>\n<td>32</td>\n<td>10</td>\n<td>32</td>\n</tr>\n<tr>\n<td>5</td>\n<td>64</td>\n<td>11</td>\n<td>32</td>\n</tr>\n<tr>\n<td>6</td>\n<td>64</td>\n<td>12</td>\n<td>32</td>\n</tr>\n<tr>\n<td>7</td>\n<td>64</td>\n<td>13</td>\n<td>32</td>\n</tr>\n<tr>\n<td>8</td>\n<td>64</td>\n<td>14</td>\n<td>32</td>\n</tr>\n<tr>\n<td>9</td>\n<td>64</td>\n<td>15</td>\n<td>32</td>\n</tr>\n<tr>\n<td>10</td>\n<td>64</td>\n<td>16</td>\n<td>32</td>\n</tr>\n<tr>\n<td>11</td>\n<td>64</td>\n<td>17</td>\n<td>32</td>\n</tr>\n<tr>\n<td>12</td>\n<td>64</td>\n<td>18</td>\n<td>32</td>\n</tr>\n<tr>\n<td>13</td>\n<td>64</td>\n<td>19</td>\n<td>32</td>\n</tr>\n<tr>\n<td>14</td>\n<td>64</td>\n<td>20</td>\n<td>32</td>\n</tr>\n<tr>\n<td>15</td>\n<td>64</td>\n<td>21</td>\n<td>32</td>\n</tr>\n<tr>\n<td>16</td>\n<td>64</td>\n<td>22</td>\n<td>32</td>\n</tr>\n<tr>\n<td>17</td>\n<td>64</td>\n<td>23</td>\n<td>32</td>\n</tr>\n<tr>\n<td>18</td>\n<td>64</td>\n<td>24</td>\n<td>32</td>\n</tr>\n<tr>\n<td>19</td>\n<td>64</td>\n<td>25</td>\n<td>32</td>\n</tr>\n<tr>\n<td>20</td>\n<td>64</td>\n<td>26</td>\n<td>32</td>\n</tr>\n<tr>\n<td>21</td>\n<td>64</td>\n<td>27</td>\n<td>32</td>\n</tr>\n<tr>\n<td>22</td>\n<td>64</td>\n<td>28</td>\n<td>32</td>\n</tr>\n<tr>\n<td>23</td>\n<td>64</td>\n<td>29</td>\n<td>32</td>\n</tr>\n<tr>\n<td>24</td>\n<td>64</td>\n<td>30</td>\n<td>32</td>\n</tr>\n<tr>\n<td>25</td>\n<td>64</td>\n<td>31</td>\n<td>32</td>\n</tr>\n<tr>\n<td>26</td>\n<td>64</td>\n<td>32</td>\n<td>32</td>\n</tr>\n</tbody>\n</table>\n\nTable 5.4: Reconstructed from first 256 coefficients\n\n---\n\nTable 5.1 shows the result of reconstruction of coefficients when the decoder is given the first 21 codes. Table 5.2 shows the result of reconstruction when the decoder is given the first 44 codes. Tables 5.3 and 5.4 are results more codes being given. The results show how the precision of the reconstructed coefficients improve as more and more codes are given. This mimics the bit truncation that would happen for rate constrained codec and how the codec would still be able to reconstruct approximate coefficients. Finally in table 5.5 we see perfect reconstruction as all the codes are given.\n\n5.4 Simulation Result for Parallel Processor Codec\n\nSimilarly, as in the single processor codec tests were performed for the parallel processor codec. The test was performed to see if the encoder and decoder encoded and decoded properly for the entire coefficients and entire codes provided. The result was found to agree with the one computed by hand. Rate constraint was not checked as each processor performs exactly the same as that of the single processor above. In other words each processor here is a smaller version of the above single processor codec.\n\nOnly the result for one subband has been shown here, in table 5.6. A hypothetical set of coefficients was chosen. However the results were checked against those worked out manually; they were the same. When the codes were input to the decoder (parallel) it reproduced the original coefficients. Thus proving that it works correctly.\n\nTable 5.6: Perfect Reconstruction from all the codes\n\n<table>\n<thead>\n<tr>\n<th>Code</th>\n<th>Coefficients (Parallel)</th>\n<th>Coefficients (Single)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>1 2 3 4 5</td>\n<td>1 2 3 4 5</td>\n</tr>\n<tr>\n<td>1</td>\n<td>6 7 8 9 10</td>\n<td>6 7 8 9 10</td>\n</tr>\n<tr>\n<td>2</td>\n<td>11 12 13 14 15</td>\n<td>11 12 13 14 15</td>\n</tr>\n<tr>\n<td>3</td>\n<td>16 17 18 19 20</td>\n<td>16 17 18 19 20</td>\n</tr>\n<tr>\n<td>4</td>\n<td>21 22 23 24 25</td>\n<td>21 22 23 24 25</td>\n</tr>\n<tr>\n<td>5</td>\n<td>26 27 28 29 30</td>\n<td>26 27 28 29 30</td>\n</tr>\n<tr>\n<td>6</td>\n<td>31 32 33 34 35</td>\n<td>31 32 33 34 35</td>\n</tr>\n<tr>\n<td>7</td>\n<td>36 37 38 39 40</td>\n<td>36 37 38 39 40</td>\n</tr>\n<tr>\n<td>8</td>\n<td>41 42 43 44 45</td>\n<td>41 42 43 44 45</td>\n</tr>\n<tr>\n<td>9</td>\n<td>46 47 48 49 50</td>\n<td>46 47 48 49 50</td>\n</tr>\n<tr>\n<td>10</td>\n<td>51 52 53 54 55</td>\n<td>51 52 53 54 55</td>\n</tr>\n<tr>\n<td>11</td>\n<td>56 57 58 59 60</td>\n<td>56 57 58 59 60</td>\n</tr>\n<tr>\n<td>12</td>\n<td>61 62 63 64 65</td>\n<td>61 62 63 64 65</td>\n</tr>\n<tr>\n<td>13</td>\n<td>66 67 68 69 70</td>\n<td>66 67 68 69 70</td>\n</tr>\n<tr>\n<td>14</td>\n<td>71 72 73 74 75</td>\n<td>71 72 73 74 75</td>\n</tr>\n<tr>\n<td>15</td>\n<td>76 77 78 79 80</td>\n<td>76 77 78 79 80</td>\n</tr>\n<tr>\n<td>16</td>\n<td>81 82 83 84 85</td>\n<td>81 82 83 84 85</td>\n</tr>\n<tr>\n<td>17</td>\n<td>86 87 88 89 90</td>\n<td>86 87 88 89 90</td>\n</tr>\n<tr>\n<td>18</td>\n<td>91 92 93 94 95</td>\n<td>91 92 93 94 95</td>\n</tr>\n<tr>\n<td>19</td>\n<td>96 97 98 99 100</td>\n<td>96 97 98 99 100</td>\n</tr>\n<tr>\n<td>20</td>\n<td>101 102 103 104 105</td>\n<td>101 102 103 104 105</td>\n</tr>\n<tr>\n<td>22</td>\n<td>111 112 113 114 115</td>\n<td>111 112 113 114 115</td>\n</tr>\n<tr>\n<td>23</td>\n<td>116 117 118 119 120</td>\n<td>116 117 118 119 120</td>\n</tr>\n<tr>\n<td>24</td>\n<td>121 122 123 124 125</td>\n<td>121 122 123 124 125</td>\n</tr>\n<tr>\n<td>25</td>\n<td>126 127 128 129 130</td>\n<td>126 127 128 129 130</td>\n</tr>\n<tr>\n<td>26</td>\n<td>131 132 133 134 135</td>\n<td>131 132 133 134 135</td>\n</tr>\n<tr>\n<td>27</td>\n<td>136 137 138 139 140</td>\n<td>136 137 138 139 140</td>\n</tr>\n<tr>\n<td>28</td>\n<td>141 142 143 144 145</td>\n<td>141 142 143 144 145</td>\n</tr>\n<tr>\n<td>29</td>\n<td>146 147 148 149 150</td>\n<td>146 147 148 149 150</td>\n</tr>\n<tr>\n<td>30</td>\n<td>151 152 153 154 155</td>\n<td>151 152 153 154 155</td>\n</tr>\n</tbody>\n</table>\nTable 5.6 Input and Output simulation results from one parallel architecture encoder and decoder (for 8 x 8)\n\n(a) Input for encoder and output from decoder\n(b) Input for decoder and output from encoder\nB. Synthesis\n\n5.5 Introduction\n\nA lot of time and effort was put in to synthesize the behavioral design of the codec. However only a few logical blocks could be synthesized and those will be presented here.\n\nThe main problem was that even if the behavioral code is in a “synthesizable” construct the Synopsys synthesis tool fails to synthesize for some reason. For instance several times it took so long (once even more than 3 days) to read the file and at the end it either gave a “not enough memory space” or just crashed the machine. An attempt was then made to synthesize the encoder not as one whole program block but in two logical parts. When this was performed the first block worked and was synthesized. The second block still gave the same problem.\n\nThere were a few but important behavioral synthesis issues encountered which required the original code for the encoder to be converted into a “synthesizable” construct. Those issues and the changes made in the program deserve mention here.\n\n5.6 Issues Encountered in Behavioral Synthesis\n\n- Asynchronous design is difficult to synthesize. In other words the synthesis requires a clock in the design for the synthesis to work properly. A global clock to synchronize the encoder parts was introduced.\n\n- Multi-dimensional arrays are not accepted for synthesis. So the original array of record used in the encoder design had to be replaced by single arrays and the associated source codes had to be changed accordingly.\n\n- While-loops were also found to be unacceptable for synthesis. They were replaced by for-loops, with definite number of loops. If-then-Exit statements were used within the for-loops to evaluate the previous while loop conditions.\nThe wait statement as such is not accepted for synthesis. It is accepted only as clock edge waits. (wait until clock'event and clock='1')\n\n5.7 Synthesizing the Significance Map Generator\n\nFigure 4.4 has been presented again to indicate which component the Significance map generator is in the encoding process.\n\n5.7.1 The Synthesis Process\n\n- Synopsys synthesis tool is invoked by using the command\n DESIGN_ANALYZER at the unix prompt.\n- The .vhd file and all the packages used are then read using the file-read command from the menu.\n- The gate level schematic can be viewed changing the level up-down from the menu.\n- Report on various aspects of the synthesized designed can also be generated using the generate-report command.\n5.7.2 Synthesized Significance Map Generator Schematics.\n\nFigure 5.2 I level schematic of Significance map generator\n\nFigure 5.3 II level Schematic of Significance map generator\nFigure 5.4 Gate Level Schematic of the whole Significance map generator\n\nFigure 5.5 Magnified part of the significance map generator\n6. CONCLUSION\n\nTo repeat here, the main aim of the project was to design, simulate and if possible, synthesize, an EZT codec implementing the EZW algorithm. The objectives that this main aim of the project translated to were:\n\n- Understanding of image compression in general and that of wavelet image compression in particular.\n- Study of wavelet transform and how it relates to image compression.\n- A thorough understanding of the EZW algorithm and the various terms used in it.\n- A good mastery of the VHDL language\n- Design and simulation of a codec using VHDL behavioral level code.\n- Synthesis of the codec.\n\n6.1 Project Achievements and Contribution\n\nThe original contributions of this project are as follows.\n\n- The most important contribution by this project has been the design of the codec itself. In the codec design, original strategies have been devised to generate the significance map, assign codes and perform successive approximation quantization, the three main steps in the EZW algorithm. The method used to decode the codes has also been an original contribution.\n\n- The EZW algorithm as such from Shapiro's paper deals at an advanced level understanding of image coding and wavelet transform. Consultation with people on authority on the topic in the engineering department at ECU, a simpler and concise algorithm has been presented.\n\n- Another important contribution by this project has been the presentation of a clear and concise explanation on this rather mathematically rigorous topic of wavelet transform. The mathematics of it was first presented, and this was followed by\ndiscussion on how this transform is practically performed using sets of high pass and low pass filters, both in continuous time and in the discrete domains. The merits of wavelet transforms were then discussed in relation to image compression.\n\n- The design, simulation and synthesis were done using the VHDL simulation tools and synthesis tools from Synopsys Inc. These tools were well explored. A number of issues pertaining to behavioral synthesis as encountered have been properly documented, together with the commands that were used to invoke the necessary simulation and synthesis tools. Anyone new to Synopsys will find this contribution very handy.\n\n- The project has also made a good study of the numerous other image compression techniques that are available today and the basis on which each of these techniques have evolved.\n\n6.2 Comments and Recommendations for Future Research\n\nOne of the great strengths of the codec designed is its ability to meet any bit rate or distortion rate exactly. But then it is not enough for a codec to just satisfy any bit rate if it can not reproduce a good enough picture. An obvious question that comes to mind is, how many bits can be truncated before the reconstructed image begins to show perceptible distortion? To answer this question a series of tests could be performed on this codec by applying suitable wavelet transform on a standard test image, obtain the coefficients, feed the coefficients to the codec and get reconstructed value of coefficients for different bit rates. The output from the decoder for different bit rates can then be inverse transformed and the different reconstructed versions for different bit rates of the same image could be compared with the original. This would give an idea of the performance of the EZT codec, besides the numerical calculation of PSNR (peak signal to noise ratio). A software program like Matlab would be suitable for this purpose.\nThe present implementation of the codec uses static data. That is, inputs to the encoder and the decoder are provided within the code at the beginning of processing. A suitable interface could be added to the current design so that inputs can be obtained from an outside source. This would take the realization of the encoder and the decoder as single stand-alone chips one last step closer. The tests suggested above can also be implemented very easily with this added interface.\n\nThe synthesized codec can then be implemented using FPGA.\n\nEven thus show of promise by the multiresolution image analysis appears to be well matched to the low-level characteristics of human vision. As this approach is developed further to incorporate additional aspects of human vision, such as spectral response characteristics, masking, pattern primitives and the like, the future of image compression looks anything but much more promising and ex\n\nThis project has contributed successfully to this state of the art technique of wavelet image compression, not only from a VLSI front but also from a research point of view.\n---**************************************************************\n-- SINGLE PROCESSOR ENCODER FOR SIMULATION\n---**************************************************************\n\n--- Embedded Zerotree Wavelet Algorithm.\n--- Image size of 8 x 8 wavelet coefficients\n--- 8 bit implementation (coefficients range from -128 to 127)\n---**************************************************************\n\nlibrary IEEE;\nlibrary WORK;\nuse WORK.TypePKGsyn.all;\nuse IEEE.std_logic_1164.all;\nuse IEEE.std_logic_signed.all;\n\nEntity FullEncoder is\n Port(clk : in std_logic; codeA: out CodeType) ;\nEnd FullEncoder;\n\nArchitecture Behavioural of FullEncoder is\n\nType CoeffRec is\n record\n ZTF: Bit;\n Encoded: Bit;\n Coeff: CoeffType;\n end record;\n\n-- DSig is to indicate if the coefficient has at least one\n-- significant coefficient for that threshold, or whether it\n-- is a leaf coefficient.\n\n-- ZTF to indicate whether or not a zerotree has been found\n-- earlier.\n\n-- Encoded to indicate if a coefficient has been encoded for\n-- any previous threshold.\n-- Coeff to contain the coefficient.\n\nType RAOfRec is Array (0 to lenth) of CoeffRec;\n\n-- to contain the input coefficients and information on each\n-- coefficient\nType OutputRA is Array (0 to 400) of CodeType;\n-- to contain the code for the coefficients from the encoding\n-- process\n\nType AllCntRA is Array (0 to 63, 0 to 6) of CodeType;\n-- to contain the quantization values of all the significant\ncodes\n\nType FirstRA is Array (0 to 5) of Bit;\n-- To indicate if the coefficient is the first significant\ncoefficient for a given threshold\n\nbegin -- start of the Architecture\n\nProcessTree: Process\nvariable T\nvariable Contnr\nvariable Parent\nvariable Child\nvariable OutCode\nvariable m\nvariable ApproxValue\nvariable SigNo\nvariable copy\nvariable First\n\nbegin -- start the process.\n\n-- *** GetCoeff ***\n-- data from Shapiro\n\nContnr (0).Coeff := 63; Contnr (1).Coeff := -34; Contnr (2).Coeff := 31;\nContnr (3).Coeff := 23; Contnr (4).Coeff := 49; Contnr (5).Coeff := 10;\nContnr (6).Coeff := 14; Contnr (7).Coeff := -13; Contnr (8).Coeff := 15;\nContnr (9).Coeff := 3; Contnr (10).Coeff := 4; Contnr (11).Coeff := 7;\nContnr (12).Coeff := 3; Contnr (13).Coeff := -12; Contnr (14).Coeff := 14;\nContnr (15).Coeff := 8; Contnr (16).Coeff := 7; Contnr (17).Coeff := 13;\nContnr (18).Coeff := 3; Contnr (19).Coeff := 4; Contnr (20).Coeff := -12;\nContnr (21).Coeff := 0; Contnr (22).Coeff := 6; Contnr (23).Coeff := -1;\nContnr (24).Coeff := 5; Contnr (25).Coeff := -7; Contnr (26).Coeff := 4;\nContnr (27).Coeff := 2; Contnr (28).Coeff := 3; Contnr (29).Coeff := 9;\nContnr (30).Coeff := 3; Contnr (31).Coeff := 2; Contnr (32).Coeff := 5;\nContnr (33).Coeff := 9; Contnr (34).Coeff := 3; Contnr (35).Coeff := 0;\nContnr (36).Coeff := -1; Contnr (37).Coeff := 47; Contnr (38).Coeff := -3;\nContnr (39).Coeff := 2; Contnr (40).Coeff := 2; Contnr (41).Coeff := -3;\nContnr (42).Coeff := 5; Contnr (43).Coeff := 11; Contnr (44).Coeff := 6;\nContnr (45).Coeff := -4; Contnr (46).Coeff := 5; Contnr (47).Coeff := 6;\nContnr (48).Coeff := 4; Contnr (49).Coeff := 6; Contnr (50).Coeff := 3;\nContnr (51).Coeff := 2; Contnr (52).Coeff := -2; Contnr (53).Coeff := 2;\nContnr (54).Coeff := 0; Contnr (55).Coeff := 4; Contnr (56).Coeff := 3;\nContnr (57).Coeff := 6; Contnr (58).Coeff := 0; Contnr (59).Coeff := 3;\nContnr(60).Coeff:=3; Contnr(61).Coeff:=6; Contnr(62).Coeff:=-4;\nContnr(63).Coeff:= 4;\nFor i in 0 to length loop -- initialize the variables\n Contnr(i).DSig := u;\n Contnr(i).Z'TF:= '0';\n Contnr(i).Encoded := '0';\nEnd loop;\n\nFirst := \"000000\";\n-- no first significant coefficients encoded.\nSigNa := 0; -- no of the significants found is zero.\nm := 0; -- point to the first element of the output array.\n\nFor I in 6 downto 0 loop -- main loop that does all the 7\n-- significance map generation and\n-- of coefficients and the\n-- subsequent encoding.\n T := Thresh(i); -- get appropraite threshold.\n Parent := 15; -- last parent coefficient\n Child := length; -- last coefficient (63rd).\n ---------------------------------------\n -- SIGNIFICANCE MAP GENERATION\n ---------------------------------------\n While Parent >=1 loop -- do until the main parent (0th\n -- coefficient).\n for j in 0 to 3 loop\n Check the four children\n -- for significance and exit if one of\n -- them is found to be significant\n If Contnr(Child - j).DSig = u then -- child is a leaf. If\n abs(Contnr(Child - j).coeff) >= T then\n Contnr(Parent).DSig := '1';\n --record descendent significant\n -- information.\n Exit; -- don't need to check other children\n Else\n Contnr(Parent).DSig := '0';\n End If;\n ElsIf Contnr(Child - j).DSig = '1' then\n Contnr(Parent).DSig := '1';\n Exit;\n Else -- Contnr(Child - j).DSig = '0'\n If abs(Contnr(Child - j).coeff) >= T then\n Contnr(Parent).DSig := '1';\n Exit;\n Else\n Contnr(Parent).DSig := '0';\n End If;\n End If;\n End Loop;\n --for one parent\n Child := Child - 4; -- for the next parent\n Parent := Parent - 1;\nEnd Loop; -- all parents\n\n-- we have reached the first parent and its three children\nFor j in 0 to 2 Loop -- main parent has only 3 children\n If Contnr(child -j).DSig = '1' then\n Contnr(Parent).DSig := '1';\n Exit;\n Else\n If abs(Contnr(child-j).Coeff) >= T then\n Contnr(Parent).DSig := '1';\n Exit;\n Else\n Contnr(Parent).DSig := '0';\n End If;\n End If;\nEnd Loop;\n\n-- SIGNIFICANCE MAP GENERATION IS COMPLETED FOR ONE THRESHOLD\n-- ASSIGN CODES\n\nParent := 0; -- start from the main parent\nChild := 1; -- child pointer point to the first child\nLoop -- till all the descendents have been encoded, happens\n -- when parent = 63 is over\n If Contnr(parent).ZTF = '1' then -- zerotree element\n If parent > 15 then -- leaf coefficient\n Null;\n Else\n For i in 0 to 3 loop\n Contnr(Child + i).ZTF := '1';\n End loop;\n End If;\n ElseIf\n Contnr(parent).Encoded = '1' then -- already encoded.\n Null;\n Else -- not encoded\n If Abs(Contnr(parent).Coeff) >= T then -- significant\n If Contnr(Parent).Coeff < 0 then\n OutCode(m) := NEG;\n m := m + 1;\n Else\n OutCode(m) := POS;\n m := m + 1;\n End If;\n End If;\n End If;\nEnd loop;\n\n-- PERFORM SUCCESSIVE APPROXIMATION QUANTIZATION FOR SIG. CODE\n\ncopy := Abs(contnr(parent).Coeff) - Thresh(1);\nCase 1 is\n When 0 => -- Threshold is 1\n Null;\nWhen $6 \\Rightarrow$ -- Threshold is 64\n\nFor $k$ in 1 downto 0 loop\n\n-- fill the approximation array\n\nIf (copy - Thresh($k$)) < 0 then\n\nApproxValue(SigNo,$k$) := NO;\n\nElse\n\nApproxValue(SigNo,$k$) := YES;\n\nEnd If;\n\nEnd Loop;\n\nOutCode($m$) := ApproxValue(SigNo,1);\n\n$m := m + 1$;\n\nWhen Others => -- Other thresholds\n\nFor $k$ in (1-1) downto 0 loop\n\nIf (copy - Thresh($k$)) < 0 then\n\nApproxValue(SigNo,$k$) := NO;\n\nElse\n\nApproxValue(SigNo,$k$) := YES;\n\nEnd If;\n\nEnd Loop;\n\nEnd Case;\n\n-- Add precision to the already encoded coefficients\n\nCase 1 is\n\nWhen $6 \\Rightarrow$ -- threshold is 64\n\nNull;\n\nWhen Others => -- other thresholds\n\nIf First($l$) = '0' then\n\nIf SigNa = 0 then\n\nNull;\n\nElse\n\nfor $r$ in 0 to (SigNa) loop\n\nOutCode($m$) := ApproxValue($r$,1);\n\nEnd loop;\n\nEnd If;\n\nFirst($l$) := '1';\n\nEnd If;\n\nEnd Case;\n\n-- increment the significant no\n\nSigNo := SigNo + 1;\n\nContnr(parent).Coeff := 0;\n\n-- set encoded coefficient to 0 to\n\n-- prevent non occurrence of ZTR\n\n-- because of it.\n\nContnr(parent).Encoded := '1';\n\n-- code insignificant\n\nElse\n\nIf Contnr(parent).DSig = '1' then\n\nOutCode($m$) := 12; -- code isolated zero\n\n$m := m + 1$;\n\nElse\n\nOutCode($m$) := ZTR; -- code zerotree root\n\nEnd If;\n\nEnd Case;\nm := m + 1;\nIf parent = 0 then\n Exit;\nElse\n If Contnr(parent).DSig = '0' then\n -- pass ZTF information to children\n For j in 0 to 3 loop;\n Contnr(child+j).ZTF := '1';\n End Loop;\n Else -- it is a leaf insignificant\n Null;\n End If;\nEnd If;\nEnd If;\nEnd If;\nEnd If;\nEnd If;\nEnd If;\nEnd If;\nEnd If;\n\nIf Parent >= 63 then -- stop when all the coefficients have\n -- been encoded.\n Exit;\nElse\n If parent = 0 then\n child := child + 3; -- 3 children for the main\n -- parent, all other parents 4\n -- each.\n Else\n Child := Child + 4;\n End If;\n parent := parent + 1;\nEnd If;\nEnd loop;\n\n-- one threshold loop\n-- set the significance (DSig) fields to 0, but not for the\n-- leaves\nFor k in 0 to length loop\n If Contnr(k).DSig = u then\n Null;\n Else\n Contnr(k).DSig := '0';\n End If;\n Contnr(k).ZTF := '0';\nEnd Loop;\n\nEnd Loop; -- all the 7 thresholds encoding loop\n\n-- display the code\nFor n in 0 to m-1 loop\n CodeA <= OutCode(n);\n wait for 5 ns;\nEnd Loop;\nWait;\nEnd Process;\nEnd of process EncodeTree;\nEnd Behavioural;\n\n-- Configuration\n\nConfiguration CFGFull_Coder of FullEncoder is\n For\n Behaviouralsyn\n End For;\nEnd CFGFull_Coder;\n\n--**************~************************************\n-- SINGLE PROCESSOR DECODER FOR SIMULATION\n--**************~************************************\n--- Decodes the codes from the single previous encoder.\n-- The result will be a single tree of 64 coefficients\n-- that existed before the encoding was performed\n---\nlibrary IEEE;\nlibrary WORK;\nuse WORK.TypePKGsyn.all;\nuse IEEE.std_logic_1164.all;\nuse IEEE.std_logic_signed.all;\n\nEntity FullDecoder is\nPort(outcoeff: out CoeffType; addr: out Integer);\nEnd FullDecoder;\n\nArchitecture Behavioural of FullDecoder is\n\nType CoeffRec is\n Record\n Coeff : CoeffType;\n ZTF: Bit;\n Decoded: Bit;\n End Record;\n-- Coeff to contain the decoded coefficient\n-- ZTF to indicate zerotree root found\n\nType CoeffRA is Array (0 to length) of CoeffRec;\nType CodeRA is Array (0 to 300) of CodeType;\nType FrstIndictr is Array (0 to 5) of Bit;\nType AddrSign is\n record\n Addr : Integer range 0 to 63;\n Sign : Bit;\n End Record;\n-- addr to store the index of the coefficient\n-- sign to store the sign of the coefficient\n\nType RAddrSign is Array (0 to length) of AddrSign;\n-- to contain the information on the decoded codes\n\nbegin\nDecodeProcess: Process\n\n variable P : Integer range 0 to 300;\n -- index the code container\n variable CoeffContnr : CoeffRA; -- contain the coeff and\n -- the associated fields\n variable CodeContnr : CodeRA; -- code container\n variable parent : Integer range 0 to length;\n -- parent pointer\n variable child : Integer range 0 to length;\n -- child pointer\n variable DecodedInfo : RAddrSign;\n -- to contain sign and index of decoded\n -- coefficients.\nvariable SigNo : Integer range 0 to 64;\n-- no of significant coefficients\n-- decoded.\nvariable First : Pos;Indictr;\n-- first sig for a threshold decoded\n-- information\nvariable Exited : Boolean;\nvariable copy1 : integer range 0 to 6;\n-- to indicate threshold\n\nbegin -- process starts\n-- get the codes\n\nCodeContnr(0) := ZTR; CodeContnr(1) := POS; CodeContnr(2) := NEG;\nCodeContnr(3) := Z; CodeContnr(4) := ZTR; CodeContnr(5) := POS;\nCodeContnr(6) := ZTR; CodeContnr(7) := ZTR; CodeContnr(8) := ZTR;\nCodeContnr(9) := ZTR; CodeContnr(10) := Z; CodeContnr(11) := ZTR;\nCodeContnr(12) := ZTR; CodeContnr(13) := ZTR; CodeContnr(14) := TR;\nCodeContnr(15) := ZTR; CodeContnr(16) := ZTR; CodeContnr(17) := ZTR;\nCodeContnr(18) := POS; CodeContnr(19) := ZTR; CodeContnr(20) := ZTR;\nCodeContnr(21) := NEG; CodeContnr(22) := YES; CodeContnr(23) := NO;\nCodeContnr(24) := YES; CodeContnr(25) := NO; CodeContnr(26) := POS;\nCodeContnr(27) := POS; CodeContnr(28) := ZTR; CodeContnr(29) := ZTR;\nCodeContnr(30) := ZTR; CodeContnr(31) := ZTR; CodeContnr(32) := ZTR;\nCodeContnr(33) := ZTR; CodeContnr(34) := ZTR; CodeContnr(35) := ZTR;\nCodeContnr(36) := ZTR; CodeContnr(37) := ZTR; CodeContnr(38) := ZTR;\nCodeContnr(39) := ZTR; CodeContnr(40) := ZTR; CodeContnr(41) := ZTR;\nCodeContnr(42) := ZTR; CodeContnr(43) := POS; CodeContnr(44) := YES;\nCodeContnr(45) := NO; CodeContnr(46) := NO; CodeContnr(47) := YES;\nCodeContnr(48) := YES; CodeContnr(49) := NO; CodeContnr(50) := POS;\nCodeContnr(51) := POS; CodeContnr(52) := NEG; CodeContnr(53) := POS;\nCodeContnr(54) := POS; CodeContnr(55) := NEG; CodeContnr(56) := ZTR;\nCodeContnr(57) := ZTR; CodeContnr(58) := NEG; CodeContnr(59) := ZTR;\nCodeContnr(60) := POS; CodeContnr(61) := ZTR; CodeContnr(62) := POS;\nCodeContnr(63) := ZTR; CodeContnr(64) := ZTR; CodeContnr(65) := NEG;\nCodeContnr(66) := ZTR; CodeContnr(67) := ZTR; CodeContnr(68) := ZTR;\nCodeContnr(69) := ZTR; CodeContnr(70) := ZTR; CodeContnr(71) := ZTR;\nCodeContnr(72) := ZTR; CodeContnr(73) := ZTR; CodeContnr(74) := POS;\nCodeContnr(75) := ZTR; CodeContnr(76) := ZTR; CodeContnr(77) := ZTR;\nCodeContnr(78) := POS; CodeContnr(79) := ZTR; CodeContnr(80) := ZTR;\nCodeContnr(81) := ZTR; CodeContnr(82) := ZTR; CodeContnr(83) := ZTR;\nCodeContnr(84) := ZTR; CodeContnr(85) := ZTR; CodeContnr(86) := ZTR;\nCodeContnr(87) := POS; CodeContnr(88) := ZTR; CodeContnr(89) := ZTR;\nCodeContnr(90) := ZTR; CodeContnr(91) := ZTR; CodeContnr(92) := ZTR;\nCodeContnr(93) := ZTR; CodeContnr(94) := ZTR; CodeContnr(95) := ZTR;\nCodeContnr(96) := ZTR; CodeContnr(97) := ZTR; CodeContnr(98) := ZTR;\nCodeContnr(99) := ZTR; CodeContnr(100) := NEG; CodeContnr(101) := YES;\nCodeContnr(102) := NO; CodeContnr(103) := NO; CodeContnr(104) := YES;\nCodeContnr(105) := YES; CodeContnr(106) := YES; CodeContnr(107) := NO;\nCodeContnr(108) := YES; CodeContnr(109) := YES; CodeContnr(110) := YES;\nCodeContnr(111) := YES; CodeContnr(112) := NO; CodeContnr(113) := YES;\nCodeContnr(114) := YES; CodeContnr(115) := NO; CodeContnr(116) := YES;\nCodeContnr(117) := YES; CodeContnr(118) := NO; CodeContnr(119) := NO;\nCodeContnr(120) := NO; CodeContnr(121) := POS; CodeContnr(122) := Z;\nCodeContnr(123) := POS; CodeContnr(124) := ZTR; CodeContnr(125) := POS;\nCodeContnr(126) := POS; CodeContnr(127) := POS; CodeContnr(128) := ZTR;\nCodeContnr(129) := POS; CodeContnr(130) := NEG; CodeContnr(131) := POS;\nEmbedded Zerotree Codec\n\n-- initialize\nFirst := \"000000\";\n\nFor m in 0 to length loop\n CoeffContnr(m).Coeff := 0;\n CoeffContnr(m).ZTF := '0';\n CoeffContnr(m).Decoded := '0';\n If m <= 5 then\n First(m) := '0';\n End If;\nEnd Loop;\n\nexited := False; -- bit truncation\nP := 0; -- index the codecontnr\nSigNo := 0;\n\nFor l in 6 downto 0 Loop -- start decoding from the main parent\n parent:= 0;\n child := 1;\n copyl := 1;\n\n While parent <= length loop -- decoding for one threshold\n If Coeffcontnr(parent).Decoded = '1' then\n Null; -- already decoded?\n -- no decoding again\n Else\n If Coeffcontnr(parent).ZTF = '1' then\n If parent <= 15 then\n -- element of zerotree\n For j in 0 to 3 loop\n -- pass ZTF info. to children\n Coeffcontnr(child+j).ZTF := '1';\n End Loop;\n End If;\n End If;\n Else\n Case Codecontnr(p) IS\n When S =>\n -- bit truncated\n Exited := True;\n Exit;\n When ZTR =>\n If parent = 0 then\n p := p + 1;\n Exit;\n -- don't need to code any more for\n -- the current threshold\n Else\n If parent <= 15 then\n -- it is not a leaf\n -- so mark its children\n For k in 0 to 3 loop\n Coeffcontnr(child + k).ZTF := '1';\n End Loop;\n End If;\n P := P + 1;\n -- prepare to read the next code\n End If;\n When POS | NEG =>\n CoeffContnr(parent).Decoded := '1';\n DcodedInfo(SigNo).Addr := parent;\n End Case;\n End If;\n End While;\nEnd Loop;\n\nKarma Wangdi\nIf CodeContnr(p) = POS then\n DcodedInfo(parent).sign := '1';\nElse\n DcodedInfo(parent).sign := '0';\nEnd If;\nCoeffContnr(parent).Coeff := Thresh(l);\nP := P + 1; -- ready to read the next code\n-- add precision to the coefficients\nCase l is\n When 6 => threshold is 64\n If CodeContnr(p) = S then\n -- bit truncated\n Exit; = true;\n -- indicate bit truncated\n Exit;\n ElsIf CodeContnr(p) = YES then\n CoeffContnr(parent).Coeff :=\n CoeffContnr(parent).Coeff +\n Thresh(l);\n -- add 64 to the coefficient\n End If;\nP := P + 1; -- next code ready to be read\n When Others =>\n If CodeContnr(p) = s then -- bit truncation\n Exit := true;\n Exit;\n ElsIf First(l) = '0' then\n -- this is the first significant of\n -- the threshold\n -- so add precision to the previously\n -- found coefficients.\n If SigNa = 0 then\n Null;\n Else\n For i in 0 to SigNa loop\n If CodeContnr(p + i) = YES then\n CoeffContnr(DcodedInfo(i)\n .Addr).Coeff :=\n CoeffContnr(DcodedInfo(i)\n .Addr).Coeff + (Thresh(l));\n Else\n Null;\n End If;\n End Loop;\n p := p + SigNo + 1;\n End If;\n First(l) := '1';\nEnd If;\nEnd Case;\n SigNa := SigNa + 1;\nWhen Others =>\n p := P + 1; -- prepare to read the next code\nEnd Case;\nEnd If;\nEnd If;\n-- house keeping\n\nIf parent >= 63 then\n Exit; -- all have been decoded for a threshold\nElse\n If parent = 0 then\n child := child + 3;\n Else\n child := child + 4;\n End If;\n parent := parent + 1;\nEnd If;\nEnd Loop; -- single threshold\nIf Exited = True then\n Exit; -- bit truncated\nElse\n For l in 0 to length loop\n CoeffContnr(l).ZTF := '0'; -- reset the ZTF field\n End Loop;\nEnd If;\nEnd Loop; -- decoding for all thresholds\n\nIf Exited = True then\n -- add the uncertainty precision to the decoded coefficients\n If copyl /= 0 then -- threshold is not 1\n For i in 0 to SigNo loop\n CoeffContnr(DcodedInfo(i).addr).Coeff :=\n CoeffContnr(DcodedInfo(i).addr).Coeff + Thresh(copyl-1);\n end loop;\n Else\n For i in 0 to SigNo loop\n CoeffContnr(DcodedInfo(i).addr).Coeff :=\n CoeffContnr(DcodedInfo(i).addr).Coeff + 1;\n end loop;\n End If;\nEnd If;\n\n-- correct the signs\n\nFor i in 0 to length loop\n If DcodedInfo(i).Sign = '1' then\n Null;\n Else\n CoeffContnr(i).Coeff := -{CoeffContnr(i).Coeff};\n End If;\nEnd Loop;\n\n--display result\n\nFor m in 0 to length loop\n OutCoeff <= CoeffContnr(m).Coeff;\n addr <= m;\n wait for 5 ns;\nEnd Loop;\nwait;\nEnd DecodeProcess;\nEnd Behavioural;\n\nConfiguration CFGNew1 of FullDecoder is\n For\n Behavioural\n End for;\n End CFGNew1;\n\n-- ENCORDER FOR SYNTHESIS\n-- The code here is same as the one for synthesis. But as pointed out\n-- in the synthesis topic multidimensional arrays (arrays of records)\n-- have been converted to simple one dimensional array. Clocking is\n-- introduced for providing synchronization, while loops have been\n-- converted to for loops and wait statements as such have been emoved.\n-- Otherwise the logic is\n-- obviously the same.\nlibrary IEEE;\nlibrary WORK;\nuse WORK.TypePKGsyn.all;\nuse IEEE.std_logic_1164.all;\nuse IEEE.std_logic_signed.all;\n\nEntity FullEncoder is\n Port(clk : in Bit; codeA: out CodeType) ;\nEnd FullEncoder;\n\nArchitecture Behaviouralsyn of FullEncoder is\n\nType OutPutRA is Array (0 to 400) of CodeType;\n-- to contain the code for the coefficients from the encoding process\nType FirstRA is Array (0 to 5) of Bit;\nType CoeffRA is array (0 to length) of CoeffType;\nType DSigRA is array (0 to length) of SigType;\nType ZTFRA is array (0 to length) of Bit;\nType EncodedRA is array (0 to length) of Bit;\nType ApproxRA is array (0 to length) of CoeffType;\n\nbegin\n EncodeTree: Process --(CLK)\n variable T: integer range 1 to 64;\n variable Parent: IndexType;\n variable Child: IndexType;\n variable OutCode : OutPutRA;\n variable m : Integer range 0 to 2048;\n variable g : Integer range 0 to 2048;\n variable SignNo : Integer range 0 to 64; -- Significant coefficient number.\n variable copy : Integer range 0 to 64;\n variable First : FirstRA; -- to indicate whether the significant coefficient\n --is the first in the level\n variable Coeff : CoeffRA;\n variable ZTF : ZTFRA;\n variable Encoded : EncodedRA;\n variable DSig : DSigRA;\n variable Zero: ApproxRA;\n variable One: ApproxRA;\n variable Two: ApproxRA;\n variable Three: ApproxRA;\n variable Four: ApproxRA;\n variable Five: ApproxRA;\n variable Six: ApproxRA;\n\nbegin\n wait until clk'event and clk = '1';\n -- *** GetCoeff ***\n Coeff(0) :=63;Coeff(1) :=-34;Coeff(2) :=-31;Coeff(3) :=23;Coeff(4) :=9;\n Coeff(5) :=10;Coeff(6) :=14;Coeff(7) :=-13;Coeff(8) :=15;Coeff(9) :=14;\n Coeff(10) :=-9;Coeff(11) :=-7;Coeff(12) :=3;Coeff(13) :=-12;Coeff(14) :=-14;\n Coeff(15) :=8;Coeff(16) :=7;Coeff(17) :=13;Coeff(18) :=3;Coeff(19) :=4;\n Coeff(20) :=-12;Coeff(21) :=7;Coeff(22) :=6;Coeff(23) :=-1;Coeff(24) :=5;\n\\begin{verbatim}\nFor i in 0 to 63 Loop --length loop\n DSig(i) := 'u';\n ZTF(i) := '0';\n Encoded(i) := '0';\nEnd loop;\n-- The DSig, ZTF and Encoded mean the same as in the simulation code\n-- except that here they are held in separate arrays.\n\nwait until clk'event and clk = '1';\nFirst := \"000000\"; -- initialize the array that indicates if the\n-- coefficient found is the first in the level\nSigNo := 0;\n-- indicates the no of the significants found\nm := 0;\n-- to serve as an index for the output array\nFor 1 in 6 downto 0 loop -- main loop that does all the 7 sig map\ngeneration of\n -- coefficients and the subsequent encoding\n T := Threshold[1]; -- choose proper threshold\n Parent := 15;\n Child := length;\n\n -- GENERATE SIGNIFICANCE MAP\n For parent in 15 downto 1 loop -- for all parents\n For j in 0 to 3 loop -- check four children for\n significance\n If DSig(child-j) = 'u' then\n If abs(Coeff(child - j)) >= T then\n DSig(parent) := '1';\n Exit;\n Else\n DSig(parent) := '0';\n End If;\n ElsIf DSig(child-j) = '1' then\n DSig(parent) := '1';\n exit;\n Else\n If abs((child - j)) >= T then\n DSig(parent) := '1';\n Exit;\n Else\n DSig(parent) := '0';\n End If;\n End If;\n End Loop; --for one parent\n Child := Child - 4;\n End Loop; -- for all but one last parent\n\\end{verbatim}\n-- we have reached the first parent and its three children in the\nsubband ***\nFor j in 0 to 2 Loop -- for three children\n If DSig(child - 1) = '1' then\n DSig(parent) := '1';\n Exit;\n ElsIf abs(Coeff(child-j)) >= T then\n DSig(parent) := '1';\n Exit;\n Else\n DSig(parent) := '0';\n End If;\nEnd Loop;\n\n-- SIGNIFICANCE MAP GENERATION FOR A THRESHOLD COMPLETED\n-- BEGIN ASSIGNING CODES\n--------------------------------------------------------------------------------\nChild := 1;\n wait until clk'event and clk = '1';\n For parent in 0 to length Loop -- encode all coefficients\n If ZTF(parent) = '1' then\n If parent > 15 then\n Null;\n Else\n For i in 0 to 3 loop\n ZTF(child + i) := '1';\n -- pass the information that a\n -- zerotree root has been\n -- ahead to the child\n End loop;\n Zerotree root has been\n wait until elk 1 event and elk =\n If the coefficient has been coded before\n don't code it.\n Null;\n ElsIf Abs(Coeff(parent)) >= T then -- significant\n If Coeff(parent) < 0 then\n OutCode(m) := NEG; -- code negative\n m := m + 1;\n Else\n OutCode(m) := POS; -- code positive\n m := m + 1;\n End If;\n -- START SUCCESSIVE APPROXIMATION QUANTIZATION\n copy := Abs(Coeff(parent)) - Thresh(1);\n Case 1 is\n When 0 => -- threshold is 1\n Null;\n When 6 => -- threshold is 64\n wait until clk'event and clk = '1';\n For k in 1 downto 0 loop\n If (copy - Thresh(k)) < 0 then -- no remainder\nCase k is\n When 0 =>\n Zero(SigNo) := NO;\n When 1 =>\n One(SigNo) := NO;\n When 2 =>\n Two(SigNo) := NO;\n When 3 =>\n Three(SigNo) := NO;\n When 4 =>\n Four(SigNo) := NO;\n When 5 =>\n Five(SigNo) := NO;\n When 6 =>\n Six(SigNo) := NO;\n When Others =>\n Null;\nEnd Case;\nElse\n Case k is\n When 0 =>\n Zero(SigNo) := YES;\n When 1 =>\n One(SigNo) := YES;\n When 2 =>\n Two(SigNo) := YES;\n When 3 =>\n Three(SigNo) := YES;\n When 4 =>\n Four(SigNo) := YES;\n When 5 =>\n Five(SigNo) := YES;\n When 6 =>\n Six(SigNo) := YES;\n When Others =>\n Null;\n End Case;\n copy := copy - Thresh(k);\nEnd If;\nEnd Loop;\nOutCode(m) := Six(SigNo);\nm := m+1;\nWhen Others =>\n For k in (1-1) downto 0 loop\n If (copy - Thresh(k)) < 0 then\n Case k is\n When 0 =>\n Zero(SigNo) := NO;\n When 1 =>\n One(SigNo) := NO;\n When 2 =>\n Two(SigNo) := NO;\n When 3 =>\n Three(SigNo) := NO;\n When 4 =>\n Four(SigNo) := NO;\n When Others =>\n Null;\n End Case;\n End If;\n End Loop;\nnull;\nend case;\nelse\n\ncase k is\n\nwhen 0 =>\n zero(signo) := yes;\nwhen 1 =>\n one(signo) := yes;\nwhen 2 =>\n two(signo) := yes;\nwhen 3 =>\n three(signo) := yes;\nwhen 4 =>\n four(signo) := yes;\nwhen others =>\n null;\nend case;\ncopy := copy - thresh(k);\nend if;\nend loop;\nend case;\n-- tag the approximate values of the coefficients\n\ncase 1 is\n\nwhen 6 =>\n null;\nwhen others =>\n if first(!) = '0' then\n if signo = 0 then\n null;\n else\n wait until clk'event and clk = '1';\n for r in 0 to length loop --(signo) loop\n if r > signo then\n exit;\n else\n case 1 is\n when 0 =>\n outcode(m) := zero(r);\n when 1 =>\n outcode(m) := one(r);\n when 2 =>\n outcode(m) := two(r);\n when 3 =>\n outcode(m) := three(r);\n when 4 =>\n outcode(m) := four(r);\n when 5 =>\n outcode(m) := two(r);\n when others =>\n null;\n end case;\n m := m + 1;\n end if;\n end loop;\n end if;\n first(!) := '1';\nend if;\nend if;\nEnd Case;\nSigNo := SigNo + 1;\nCoeff(parent) := 0;\nEncoded(parent) := '1';\n-- code insignificant\nElse\nIf DSig(parent) = '1' then\nOutCode(m) := Iz;\nm := m + 1;\nElse\nOutCode(m) := ZTR;\nm := m + 1;\nIf parent = 0 then\nExit;\nElseIf DSig(parent) = '0' then\nwait until clk'event and clk = '1';\nFor j in 0 to 3 loop\nZTF(child + j) := '1';\nEnd Loop;\nwait until clk'event and clk = '1';\nElse -- it is a leaf insignificant\nNull;\nEnd If;\nEnd If;\nEnd If;\nIf parent >= 15 then\nNull;\nElseIf parent = 0 then\nchild := child + 3;\nElse\nChild := Child + 4;\nEnd If;\nEnd Loop;\n-- one threshold loop\n-- set the significance (DSig) found earlier threshold to 0\nFor k in 0 to length loop\nIf DSig(k) = u then\nNull;\nElse\nDSig(k) := '0';\nEnd If;\nZTF(k) := '0';\nEnd Loop;\nEnd Loop; -- all the 7 arranging and encoding loop\nwait until clk'event and clk = '1';\n\n-- display the code\nFor n in 0 to 65 loop --(m-1)\nCodeA <= OutCode(n);\nEnd Loop;\nwait until clk'event and clk = '1';\n\nEnd Process;\n-- end of EncodeTree process\nEnd Behavioursyn;\n--- Configuration\n\nConfiguration CFGFullCoder of FullEncoder is\nFor\n BehaviouralSyn\nEnd For;\nEnd CFGFullCoder;\n\n--- END\n\n---*******************************************************\n--- 3 Parallel Processor Encoder\n---*******************************************************\n--- The same strategy of significance map generation, code assignment\n--- and successive approximation quantization is used. There are three\n--- fundamental differences from the single processor encoder.\n--- The first parent in each of the three processors has only one child\n--- And to determine the descendent significance of the first parent\n--- information is required from the other two processors. And each\n--- processor processes only a third of the coefficients, i.e. one\n--- processor encodes one subband of the three Processor for subband A's\n--- code is shown in full. Since the other two\n--- are the same we show only how the three relate to the fourth\n--- Processor and donot repeat the code for the other two processors in\n--- the interest of space. They are just the repetition of the first one\n-- The same types and variable used earlier in the single processor are\n-- used here as well. For the three processors the variables and\n-- signals are appended with A, B, C so as to differentiate their use\n-- in three processors\n\nlibrary IEEE;\nlibrary WORK;\nuse WORK.TypePKG.all;\nuse IEEE.std_logic_1164.all;\nuse IEEE.std_logic_signed.all;\n-- Embedded Zerotree Wavelet Algorithm.\n-- Image 8 by 8\n-- 8 bit implementation\n\nEntity FullEncoder is\n Port(codeA, codeB, codeC : out CodeType);\nEnd FullEncoder;\n\nArchitecture Behaviourall of FullEncoder is\n\n Type CoeffRec is\n record\n DSig: SigType;\n -- '1' for yes, '0' for no and 'u'\n -- for no children (leaves)\n ZTF: Bit;\n Encoded: Bit;\n Coeff: CoeffType;\n End Record;\n\n Type RAOfRec is Array (0 to lenth) of CoeffRec;\n -- to contain the input coefficients and information on each\n -- coefficient\n\n Type OutPutRA is Array (0 to 150) of CodeType;\n -- to contain the code for the coefficients from the encoding process\n\n Type AllQntRA is Array (0 to 21, 0 to 6) of CodeType;\n -- to contain the quantization values of all the codes\n\n Type FirstRA is Array (0 to 5) of Bit;\n\n Signal A, B, C : Bit;\nbegin\n\nControlProcesses: Process\nbegin\n -- control the start of the three processes\n A <= '1';\n B <= '1';\n C <= '1';\n Wait Until AYes = '1' and BYes = '1' and CYes = '1';\n A <= '0';\n B <= '0';\n C <= '0';\nEnd Process;\n\nSubband_A: Process -- to process subband A\n\nbegin\n-- process subband_A\n\n-- Initialization\nFor i in 0 to length loop\n C0ntnr(i).DSig := u;\n Contnr(i).ZTF := '0';\n Contnr(i).Encoded := '0';\nEnd loop;\n\nFirst := \"000000\"; -- initialize the array that indicates if the significant coefficient found is the first in the level\nContnr(0).Coeff := -83; Contnr(1).Coeff := -31; Contnr(2).Coeff := 15;\nContnr(3).Coeff := 14; Contnr(4).Coeff := -9; Contnr(5).Coeff := -7;\nContnr(6).Coeff := -5; Contnr(7).Coeff := 9; Contnr(8).Coeff := 3;\nContnr(9).Coeff := 0; Contnr(10).Coeff := -1; Contnr(11).Coeff := 47;\nContnr(12).Coeff := -3; Contnr(13).Coeff := 2; Contnr(14).Coeff := 2;\nContnr(15).Coeff := -3; Contnr(16).Coeff := 5; Contnr(17).Coeff := 11;\nContnr(18).Coeff := 6; Contnr(19).Coeff := -4; Contnr(20).Coeff := 5;\nContnr(21).Coeff := 6;\n\n-- Inputs/Coefficients ready\nm := 0; -- to serve as an index for the output array\nSigNo := 0; -- indicates the no of the significant coefficients found\n\nFor l in 6 downto 0 loop -- main loop that does all the encoding\n T := Thresh(l);\n Parent := 5;\n Child := length;\n -------------------------------\n -- GENERATE SIGNIFICANCE MAP\n -------------------------------\n While Parent >= 1 loop\n for j in 1 to 4 loop\n If Contnr(Child - j + 1).DSig = u then\n If abs(Contnr(Child - j + 1).coeff) >= T then\n Contnr(Parent).DSig := '1';\n Exit;\n Else\n Contnr(Parent).DSig := '0';\n End If;\n ElsIf Contnr(Child - j + 1).DSig = '1' then\n Contnr(Parent).DSig := '1';\n exit;\n Else -- Contnr(Child - j + 1).DSig = '0'\n If abs(Contnr(Child - j + 1).coeff) >= T then\n Contnr(Parent).DSig := '1';\n Exit;\n Else\n Contnr(Parent).DSig := '0';\n End If;\n End If;\n End Loop;\n Child := Child - 4;\n Parent := Parent - 1;\n End Loop;\n -- we have reached the first parent and its only child in the subband\nIf Contnr(1).DSig = '1' then\n Contnr(0).DSig := '1';\nElse\n If abs(Contnr(1).Coeff) >= T then\n Contnr(0).DSig := '1';\n Else\n Contnr(0).DSig := '0';\n End If;\nEnd If;\n\n-- SIGNIFICANCE MAP GENERATION COMPLETED\n-- ASSIGN CODES\n\n-- send zeroth (0) coefficient and the significance of its first\n-- descendants\n-- to another process to\n-- code the main parent\n\nIf Contnr(0).Encoded = '0' then\n -- do the following only if the main parent hadn't been encoded\n MainParent <= Contnr(0).Coeff;\n If Contnr(0).DSig = '1' then\n ASig <= '1'; -- main parent from processor A has\n -- descendent significant\n Else\n ASig <= '0'; -- main parent does not have any significant\n -- descendent in subband A\n End If;\n TCopy <= T;\n FromA <= '1'; -- subband A has reached to process the main\n -- parent\n Wait until ADone = '1';\n FromA <= '0';\n OutCode(m) := ACode;\n m := m + 1;\n Case Acode is\n When POS | NEG =>\n -- start quantization for main parent\n copy := Abs(contnr(0).Coeff) - Thresh(1);\n For k in (1-1) downto 0 loop\n If (copy - Thresh(k)) < 0 then\n ApproxValue(SigNo,k) := NO;\n Else\n ApproxValue(SigNo,k) := YES;\n copy := copy - Thresh(k);\n End If;\n End Loop;\n -- tag the approximate values of the coefficients\n Case k is\n When 6 =>\n -- OutCode(m) := ApproxValue(SigNo,1);\n -- m := m + 1;\n Null;\n When Others =>\n If First(1) = '0' then\n for r in 0 to (SigNo-1) loop\n OutCode(m) := ApproxValue(r,1);\n End for;\n End If;\n End Case;\n Null;\n End Case.\nEnd If;\n\nKarma Wangdi\nm := m + 1;\nEnd loop;\nFirst(l) := '1';\nEnd If;\nEnd Case;\n-- increment the no of significant found\nIf SignNo < 21 then\n SignNo := SignNo + 1;\nEnd If;\nContnr(0).Encoded := '1';\nContnr(0).Coeff := 0;\n\nWhen ZTR =>\n Contnr(0).ZTF := '1';\nWhen Others =>\n Null;\nEnd Case;\nEnd If;\n-- encode the rest\nIf Contnr(0).ZTF = '1' then\n Null;\nElse -- only if the main parent is not a zerotree root\n If Contnr(1).Encoded = '1' then\n Null;\n Else\n If Abs(Contnr(1).Coeff) >= T then\n If Contnr(1).Coeff < 0 then\n OutCode(m) := NEG;\n Else\n OutCode(m) := POS;\n End If;\n m := m + 1;\n copy := Abs(contnr(1).Coeff) - Thresh(1);\n For k in (1-1) downto 0 loop -- prepare the table of\n -- coefficients\n If copy - Thresh(k) < 0 then\n ApproxValue(SigNo,k) := NO;\n Else\n ApproxValue(SigNo,k) := YES;\n copy := copy - Thresh(k);\n End If;\n End Loop;\n -- tag the approximate values of the coefficients\n Case l is\n When 6 =>\n OutCode(m) := ApproxValue(SigNo,1);\n m := m + 1;\n When Others =>\n If First(l) = '0' then\n for r in 0 to (SigNo-1) loop\n OutCode(m) := ApproxValue(r,1);\n m := m + 1;\n End loop;\n If First(l) = '1';\n End If;\n End Case;\n End Case;\n End Else;\nEnd Case;\nIf $\\text{SigNo} < 21$ then\n $\\text{SigNo} := \\text{SigNo} + 1$;\nEnd If;\n\n$\\text{Contnr}(1).\\text{Coeff} := 0$;\n$\\text{Contnr}(1).\\text{Encoded} := '1'$;\n\nElse\n If $\\text{Contnr}(1).\\text{DSig} = '1'$ then\n $\\text{OutCode}(m) := \\text{IZ}$;\n $m := m + 1$;\n ElseIf $\\text{Contnr}(1).\\text{DSig} = '0'$ then\n $\\text{OutCode}(m) := \\text{ZTR}$;\n $\\text{Contnr}(1).\\text{ZTF} := '1'$;\n $m := m + 1$;\n Else\n Null;\n End If;\nEnd If;\n\n-- start coding the other descendents from 2 and all\n\nIf $\\text{Contnr}(1).\\text{ZTF} = '1'$ then\n Null;\nElse\n parent := 1;\n child := 2;\nLoop -- till all the descendents have been encoded, happens when\n -- parent = 5 is over\n If $\\text{Contnr}(\\text{Parent}).\\text{ZTF} = '1'$ then\n For i in 1 to 4 loop\n $\\text{Contnr}(\\text{Child} + i - 1).\\text{ZTF} := '1' ;$ -- pass the\n -- information that a Zerotree\n -- root has been found ahead to\n -- the children\n End loop;\n Else\n For i in 1 to 4 loop\n If $\\text{Contnr}(\\text{Child} + i - 1).\\text{Encoded} = '1'$ then\n -- if the coefficient has been coded before don't\n -- code it\n Null;\n Else\n If $\\text{Abs}(\\text{Contnr}(\\text{Child} + i - 1).\\text{Coeff}) >= T$ then\n If $\\text{Contnr}(\\text{Child} + i - 1).\\text{Coeff} < 0$ then\n $\\text{OutCode}(m) := \\text{NEG}$;\n Else\n $\\text{OutCode}(m) := \\text{POS}$;\n End If;\n $m := m + 1$;\n End If;\n End If;\n End loop;\n End If;\nEnd Loop;\n\n-- start quantization\n$\\text{copy} := \\text{Abs}(\\text{contnr}(\\text{Child} + i - 1).\\text{Coeff}) - \\text{Thresh}(1)$;\nCase 1 is\nWhen 0 =>\n Null;\nWhen Others =>\n For k in (l-1) downto 0 loop\n If (copy - Thresh(k)) < 0 then\n ApproxValue(SigNo,k) := NO;\n Else\n ApproxValue(SigNo,k) := YES;\n copy := copy - Thresh(k);\n End If;\n End Loop;\n End Case;\n-- tag the approximate values of the coefficients\nCase 1 is\n When 6 =>\n OutCode(m) := ApproxValue(SigNo,1);\n m := m + 1;\n When Others =>\n If First(1) = '0' then\n for r in 0 to (SigNo-1) loop\n OutCode(m) :=\n ApproxValue(r,1);\n m := m + 1;\n End loop;\n First(1):='1';\n End If;\n End Case;\n If SigNo < 21 then\n SigNo := SigNo + 1;\n End If;\n Contnr(Child + i - 1).Coeff := 0;\n Contnr(Child + i - 1).Encoded := '1';\n Else\n If Contnr(Child + i - 1).DSig = '1' then\n OutCode(m) := IZ;\n m := m + 1;\n ElseIf Contnr(Child + i - 1).DSig = '0' then\n OutCode(m) := ZTR;\n Contnr(Child + i - 1).ZTF := '1';\n m := m + 1;\n Else -- if it is a leaf coefficient\n OutCode(m) := ZTR;\n m := m + 1;\n End If;\n End If;\n End If;\n End Loop;\n If Parent >= 5 then\n Exit;\n Else\n Child := Child + 4;\n Parent := Parent + 1;\n End If;\n End loop;\n End If;\n End If;\n-- reset the fields\nFor k in 1 to (lenth + 1) loop\n If Contnr(k-1).DSig = u then\n null;\n Else\n Contnr(k-1).DSig := '0';\n End If;\n Contnr(k-1).ZTF := '0';\nEnd Loop;\nEnd Loop; -- all the 7 arranging and encoding loop\n\n-- display the code\n\nFor n in 0 to m-1 loop\n CodeA <= OutCode(n);\n wait for 5 ns;\nEnd Loop;\nAyes <= '1';\nWait until A = '1';\nEnd Process; -- end of process Subband_A\n\nSubband_B: Process\n\n---------------------------------------------------------------------------------------------------------------------\n-- SAME AS PROCESSOR FOR SUBBAND_A, INPUTS ARE FROM SUBBAND_B\n-- GENERATES SIGNIFICANCE MAP, SENDS THE MAIN PARENT'S DESCENDENDT\n-- INFORMATION TO A FOURTH PROCESSOR AND ENCODES AS DONE IN SUBBAND_A\n---------------------------------------------------------------------------------------------------------------------\n\nSubband_C: Process\n\n---------------------------------------------------------------------------------------------------------------------\n-- SAME AS PROCESSOR FOR SUBBAND_A AND B, BUT INPUTS FROM SUBBAND_C\n-- GENERATES SIGNIFICANCE MAP, SENDS THE MAIN PARENT'S DESCENDENDT\n-- INFORMATION TO A FOURTH PROCESSOR AND ENCODES AS DONE IN SUBBAND_A\n---------------------------------------------------------------------------------------------------------------------\n\n---------------------------------------------------------------------------------------------------------------------\n-- PROCESS THAT DETERMINES THE DESCENDENT SIGNIFICANCE OF THE MAIN\n-- PARENT AND SENDS THE INFORMATION TO THE INDIVIDUAL PROCESSORS\n---------------------------------------------------------------------------------------------------------------------\nDetMain: Process\n\nvariable Thold: Integer range 1 to 64;\nvariable CopyCoeff: CoeffType;\n\nbegin\n\nWait Until FromA = '1' and FromB = '1' and FromC = '1';\n-- get information from all the\n-- three processes of the th~ ~ subbands\nADone <= '0';\nBDone <= '0'; -- keep the processors waiting\nCDone <= '0';\nCopyCoeff := MainParent;\nIf Abs(CopyCoeff) >= Thold then\n If CopyCoeff < 0 then\n ACode <= NEG;\n BCode <= NEG;\n CCode <= NEG;\n Else\n ACode <= POS;\n BCode <= POS;\n CCode <= POS;\n End IF;\nElse\n If ASig = '1' or BSig = '1' or CSig = '1' then\n ACode <= IZ;\n BCode <= IZ;\n CCode <= IZ;\n Else\n ACode <= ZTR;\n BCode <= ZTR;\n CCode <= ZTR;\n End If;\nEnd IF;\nADone <= '1';\nBDone <= '1';\nCDone <= '1';\nEnd Process;\nEnd Behaviourall;\n\nConfiguration CFGFull_Coder of FullEncoder is\n\nFor\n Behaviourall\nEnd For;\nEnd CFGFull_Coder;\nPARALLEL ARCHITECTURE DECODER\n\nThe three parallel decoders are exactly the same. So, only one is shown. As explained in chapter 4 this decoder is a smaller version of the single processor decoder, though it does not necessarily be. It is at least as implemented in this project. The only main difference is that the first parent has only one child here, whereas in the single processor codec we had three children. Rest, is the same. The variable names used here are same as those used in the other decoder. Hence only modest explanations are provided here as they are just the repetition of what we have been explained.\nlibrary IEEE;\nlibrary WORK;\nuse WORK.TypePKG.all;\nuse IEEE.std_logic_signed.all;\n\nEntity FullDecoder is\nPort (codeout: out CodeType);\nEnd FullDecoder;\n\nArchitecture Behavioural of FullDecoder is\n\nType CoeffRec is\nRecord\n Coeff : CoeffType;\n ZTF : Bit;\n Decoded : Bit;\nEnd Record;\n\nType CoeffRA is Array (0 to length) of CoeffRec;\nType CodeRA is Array (0 to 264) of CodeType;\nType FirstIndicator is Array (0 to 5) of Bit;\nType AddrSign is\n record\n Addr: Integer range 0 to 21;\n Sign: Bit;\n End Record;\n\nType RAddrSign is Array (0 to length) of AddrSign; -- to contain the\ninformation on the decoded codes\n\nbegin\nDecodeProcess: Process\n\n variable P : Integer range 0 to 264;\n variable CoeffContainer : CoeffRA;\n variable CodeContainer : CodeRA;\n variable parent : Integer range 0 to 6;\n variable child : Integer range 0 to length;\n variable DecodedInfo : RAddrSign;\n variable SignNo : Integer range 0 to 22; --significant number\n variable First : FirstIndicator;\n\n begin\n\n CodeContainer(0):=NEG;\n CodeContainer(1):=ZTR;\n CodeContainer(2):=IZ;\n CodeContainer(3):=ZTR;\n CodeContainer(4):=IZ;\n CodeContainer(5):=ZTR;\n CodeContainer(6):=ZTR;\n CodeContainer(7):=ZTR;\n CodeContainer(8):=POS;\n\nKarma Wangdi\nCodeContnr(9) := NO; CodeContnr(10) := ZTR; CodeContnr(11) := ZTR;\nCodeContnr(12) := NEG; CodeContnr(13) := YES; CodeContnr(14) := NO;\nCodeContnr(15) := ZTR; CodeContnr(16) := ZTR; CodeContnr(17) := ZTR;\nCodeContnr(18) := ZTR; CodeContnr(19) := POS; CodeContnr(20) := NO;\nCodeContnr(21) := YES; CodeContnr(22) := YES; CodeContnr(23) := POS;\nCodeContnr(24) := NEG; CodeContnr(25) := ZTR; CodeContnr(26) := ZTR;\nCodeContnr(27) := POS; CodeContnr(28) := ZTR; CodeContnr(29) := ZTR;\nCodeContnr(30) := ZTR; CodeContnr(31) := ZTR; CodeContnr(32) := ZTR;\nCodeContnr(33) := ZTR; CodeContnr(34) := ZTR; CodeContnr(35) := ZTR;\nCodeContnr(36) := POS; CodeContnr(37) := NEG; CodeContnr(38) := NO;\nCodeContnr(39) := YES; CodeContnr(40) := YES; CodeContnr(41) := YES;\nCodeContnr(42) := YES; CodeContnr(43) := NO; CodeContnr(44) := NO;\nCodeContnr(45) := NO; CodeContnr(46) := NEG; CodeContnr(47) := ZTR;\nCodeContnr(48) := ZTR; CodeContnr(49) := ZTR; CodeContnr(50) := ZTR;\nCodeContnr(51) := ZTR; CodeContnr(52) := ZTR; CodeContnr(53) := ZTR;\nCodeContnr(54) := POS; CodeContnr(55) := POS; CodeContnr(56) := ZTR;\nCodeContnr(57) := POS; CodeContnr(58) := POS; CodeContnr(59) := POS;\nCodeContnr(60) := YES; CodeContnr(61) := YES; CodeContnr(62) := YES;\nCodeContnr(63) := YES; CodeContnr(64) := YES; CodeContnr(65) := NO;\nCodeContnr(66) := NO; CodeContnr(67) := YES; CodeContnr(68) := YES;\nCodeContnr(69) := NO; CodeContnr(70) := NO; CodeContnr(71) := YES;\nCodeContnr(72) := NO; CodeContnr(73) := NO; CodeContnr(74) := YES;\nCodeContnr(75) := ZTR; CodeContnr(76) := ZTR; CodeContnr(77) := NO;\nCodeContnr(78) := POS; CodeContnr(79) := POS; CodeContnr(80) := NEG;\nCodeContnr(81) := ZTR; CodeContnr(82) := ZTR; CodeContnr(83) := YES;\nCodeContnr(84) := YES; CodeContnr(85) := YES; CodeContnr(86) := YES;\nCodeContnr(87) := NO; CodeContnr(88) := YES; CodeContnr(89) := YES;\nCodeContnr(90) := YES; CodeContnr(91) := YES; CodeContnr(92) := YES;\nCodeContnr(93) := YES; CodeContnr(94) := NO; CodeContnr(95) := NO;\nCodeContnr(96) := YES; CodeContnr(97) := NO; CodeContnr(98) := YES;\nCodeContnr(99) := YES; CodeContnr(100) := NO; CodeContnr(101) := NO;\nCodeContnr(102) := YES; CodeContnr(103) := NEG; CodeContnr(104) := NEG;\n\n-- initialize\n\nFor m in 0 to length loop\n CoeffContnr(m).Coeff := 0;\n CoeffContnr(m).ZTF := '0';\n CoeffContnr(m).Decoded := '0';\n If m <= 5 then\n First(m) := '0';\n End If;\nEnd Loop;\n\nP := 0; -- index the codecontr\nSigNo := 0;\nFor l in 6 downto 0 Loop\n parent := 0;\n child := 0;\n\n For j in 0 to length loop -- for one threshold\n If CoeffContnr(j).Decoded = '1' then\n null;\n Else\n If CoeffContnr(j).ZTF = '1' then\n\nnull;\n\nElse\n\nCase Codecontnr(p) IS\n\nWhen ZTR =>\n\nIf ((j = 0) OR (j = 1)) then\n\nparent := 0;\nchild := 0;\np := p + 1;\nExit;\n\nElse\nIf ((parent /= 0) AND (parent <= 5)) then\n-- it is not a leaf\n-- so mark its children\nFor k in 0 to 3 loop\nCoeffContnr(child + k).ZTF := '1';\nEnd Loop;\nEnd If;\nEnd If;\n\nWhen POS | NEG =>\nCoeffContnr(j).Decoded := '1';\nSigNo := SigNo + 1;\nDcodedInfo(SigNo-1).Addr := j;\nIf Codecontnr(p) = POS then\nDcodedInfo(j).sign := '1';\nElse\nDcodedInfo(j).sign := '0';\nEnd If;\nCoeffContnr(j).Coeff := (Thresh(!));\nIf 1 <= 5 then\nIf First(!) = '0' then\n-- this is the first significant in the level\n-- so add precision to the previously found\n-- coefficients\nFor i in 1 to SigNo-1 loop\nIf Codecontnr(p + i) = YES then\naddr <= DcodedInfo(i-1).addr;\nwait for 5 ns;\naddr <= 22;\nwait for 5 ns;\nCoeffContnr(DcodedInfo(i-1).Addr).Coeff :=\nCoeffContnr(DcodedInfo(i-1).Addr).Coeff +\n(Thresh(!));\nElse\nNull;\nEnd If;\nEnd Loop;\nFirst(!) := '1';\np := p + SigNo -1;\nEnd If;\nEnd If;\n\nWhen Others =>\nNull;\nEnd Case;\np := P + 1; -- prepare to read the next code\nEnd If;\nEnd If;\n-- house keeping\nIf j >= 21 then\nExit;\nElse\nIf j => 1 then\nIf parent = 0 then\nParent := 2;\nchild := 6;\nElse\nCase parent IS\nWhen 6 =>\nNull;\nWhen 5 =>\nParent := parent + 1;\nWhen Others =>\nParent := parent + 1;\nchild := child + 4;\nEnd Case;\nEnd If;\nEnd If;\nEnd If;\nEnd Loop;\nEnd Loop;\n\n-- correct the signs\nFor i in 0 to lenth loop\nIf DcodedInfo(i).Sign = '1' then\nNull;\nElse\nCoeffContnr(i).Coeff := - (CoeffContnr(i).Coeff);\nEnd If;\nEnd Loop;\n\n-- display result\nFor m in 0 to lenth loop\nOutCoeff <= CoeffContnr(m).Coeff;\nwait for 5 ns;\nEnd Loop;\nWait;\nEmcdcd\nZcrotrcc Cmlcc\nEnd Process;\nEnd Behavioural;\n\nConfiguration CFGNew1 of FullDecoder is\nfor Behavioural\nEnd for;\nEnd CFGNew1;\n\n----------------------------------------------------------------------\nEND\n--*********************************************************************\n-- Significance Map Generator: Code that has been Successfully\n-- Synthesized\n--*********************************************************************\n-- This the one logical portion of the encoder that has been\n-- synthesized. Significance Generation code has appeared before. Of\n-- noteworthy is the replacement of records by arrays, introduction of\n-- clocking, use of only for loops, and no wait statement as such being\n-- used. It is only used with rising edge of a clock. Otherwise, here\n-- too the codes are similar to those found earlier\n--*********************************************************************\n\nlibrary IEEE;\nlibrary WORK;\n\nKarma Wangdi\nEmbedded Zerotree Codec\n\nuse WORK.TypePKGsyn.all;\nuse IEEE.std_logic_1164.all;\nuse IEEE.std_logic_signed.all;\n\n-- Embedded Zerotree Wavelet Algorithm.\n-- Image 8 by 8\n-- 8 bit implementation\n\nEntity SigMapGen is\n Port(clk : in Bit; codeA: out CodeType);\nEnd SigMapGen;\n\nArchitecture Behave of SigMapGen is\n\nType OutPutRA is Array (0 to 200) of CodeType;\n-- to contain the code for the coefficients from the encoding process\n\nType FirstRA is Array (0 to 5) of Bit;\nType CoeffRA is array (0 to length) of CoeffType;\nType DSigRA is array (0 to length) of SigType;\nType ZTFRA is array (0 to length) of Bit;\nType EncodedRA is array (0 to length) of Bit;\nType ApproxRA is array (0 to length) of CodeType;\n\nbegin\n Arrage: Process --(CLK)\n variable T: integer range 1 to 64;\n\n variable Parent: IndexType;\n\n variable Child: IndexType;\n\n variable OutCode : OutPutRA;\n\n variable m : Integer range 0 to 2048;\n variable q : Integer range 0 to 2048;\n variable SigNo : Integer range 0 to 64;\n -- Significant coefficient number.\n variable copy : Integer range 0 to 64;\n variable First : FirstRA; -- to indicate whether the significant\n -- coefficient is the first in the level\n variable Coeff : CoeffRA;\n variable ZTF : ZTFRA;\n variable Encoded : EncodedRA;\n variable DSig : DSigRA;\n variable Zero : ApproxRA;\n variable One : ApproxRA;\n variable Two : ApproxRA;\n variable Three : ApproxRA;\n variable Four : ApproxRA;\n variable Five : ApproxRA;\n variable Six : ApproxRA;\nbegin\n\nwait until clk'event and clk = '1';\n\n-- *** GetCoeff here ***\nFor i in 0 to 63 Loop --lenth loop\n DSig(i) := u;\n ZTF(i):= '0';\n Encoded(i) := '0';\nEnd loop;\nwait until clk'event and clk = '1';\nFirst := \"000000\"; -- initialize the array that indicates if the significant -- coefficient found is the first in the level\nSignNo := 0; -- indicates the no of the signficants found\nm := 0; -- to serve as an index for the output array\nParent := 15;\nChild := length;\nFor parent in 15 downto 1 loop\n for j in 0 to 3 loop\n If DSig(child-j) = u then\n If abs(Coeff(child - j))>= T then\n DSig(parent) := '1';\n Exit;\n Else\n DSig(parent) := '0';\n End If;\n ElsIf DSig(child-j) = '1' then\n DSig(parent) := '1';\n exit;\n Else\n If abs((child -j))>= T then\n DSig(parent) := '1';\n Exit;\n Else\n DSig(parent):= '0';\n End If;\n End If;\n End Loop; --for one parent\nChild := Child - 4;\nEnd Loop; -- all parents\n\n-- we have reached the first parent and its three children in the subband\nFor j in 0 to 2 Loop\n If DSig(child -1) = '1' then\n DSig(parent) := '1';\n Exit;\n ElsIf abs(Coeff(child-j)) >= T then\n DSig(parent) := '1';\n Exit;\n Else\n DSig(parent) := '0';\n End If;\nEnd Loop;\nEnd Process;\nEnd Behave;\nConfiguration CFG_Arranger of SigMapGen is\n For\n Behave\n End For;\nEnd CFG_Arranger;\n\nEND\nBibliography\n\n\nBoca Raton: CRC Press\n\n\nAmsterdam: ELSEVIER\n\n\n"}}},{"rowIdx":84,"cells":{"id":{"kind":"string","value":"b77d0c32fa6651a11133530c3304fe2f7d63f56e"},"text":{"kind":"string","value":"LEBANESE AMERICAN UNIVERSITY\n\nSET-BASED APPROACH FOR EFFICIENT EVALUATION AND ANALYSIS OF XACML POLICIES\n\nBy\n\nHUSSEIN M. JEBBAOUI\n\nA thesis\nSubmitted in partial fulfillment of the requirements for the degree of Master of Science in Computer Science\n\nSchool of Arts and Sciences\nMay 2014\nTHESIS APPROVAL FORM\n\nStudent Name: ________________________ Hussein Jebbaoui ________________________ I.D. #: ________________________ 201003548\n\nThesis Title: SBA-XACML: Set-based Approach for Efficient Evaluation and Analysis of XACML Policies\n\nProgram: Masters in Computer Science\nDepartment: Computer Science and Mathematics\n\nSchool: Arts and Sciences\n\nThe undersigned certify that they have examined the final electronic copy of this thesis and approved it in Partial Fulfillment of the requirements for the degree of:\n\nMasters of Science in the major of Computer Science\n\nThesis Advisor’s Name: ________________________ Dr. Azzam Mourad ________________________ Signature ________________________ Date: 05/05/14\n\nCommittee Member’s Name: ________________________ Dr. Faisal Abu-Khzam ________________________ Signature ________________________ Date: 05/05/14\n\nCommittee Member’s Name: ________________________ Dr. Samer Habre ________________________ Signature ________________________ Date: 05/05/14\nTHESIS COPYRIGHT RELEASE FORM\n\nLEBANESE AMERICAN UNIVERSITY NON-EXCLUSIVE DISTRIBUTION LICENSE\n\nBy signing and submitting this license, you (the author(s) or copyright owner) grants to Lebanese American University (LAU) the non-exclusive right to reproduce, translate (as defined below), and/or distribute your submission (including the abstract) worldwide in print and electronic format and in any medium, including but not limited to audio or video. You agree that LAU may, without changing the content, translate the submission to any medium or format for the purpose of preservation. You also agree that LAU may keep more than one copy of this submission for purposes of security, backup and preservation. You represent that the submission is your original work, and that you have the right to grant the rights contained in this license. You also represent that your submission does not, to the best of your knowledge, infringe upon anyone's copyright. If the submission contains material for which you do not hold copyright, you represent that you have obtained the unrestricted permission of the copyright owner to grant LAU the rights required by this license, and that such third-party owned material is clearly identified and acknowledged within the text or content of the submission. IF THE SUBMISSION IS BASED UPON WORK THAT HAS BEEN SPONSORED OR SUPPORTED BY AN AGENCY OR ORGANIZATION OTHER THAN LAU, YOU REPRESENT THAT YOU HAVE FULFILLED ANY RIGHT OF REVIEW OR OTHER OBLIGATIONS REQUIRED BY SUCH CONTRACT OR AGREEMENT. LAU will clearly identify your name(s) as the author(s) or owner(s) of the submission, and will not make any alteration, other than as allowed by this license, to your submission.\n\nName: Hussein Jebbaoui\n\nSignature: \n\nDate: Apr. 5, 2014\nPLAGIARISM POLICY COMPLIANCE STATEMENT\n\nI certify that:\n\n- I have read and understood LAU’s Plagiarism Policy.\n- I understand that failure to comply with this Policy can lead to academic and disciplinary actions against me.\n- This work is substantially my own, and to the extent that any part of this work is not my own I have indicated that by acknowledging its sources.\n\nName: Hussein Jebbaoui\n\nSignature: [Signature]\n\nDate: Apr. 5, 2014\nDedication\n\nTo my family\nACKNOWLEDGMENTS\n\nFirst of all, I would like to thank God for giving me the opportunity to complete this work successfully. I would like to express my gratitude and appreciation to my advisor, Dr. Azzam Mourad, for his excellent support and caring. It was a great privilege and honor to have worked under his guidance and provision. I would also like to thank him for his friendship and unconditional support.\n\nI also would like to thank my committee members Dr. Samer Habre and Dr. Faisal Abu-Khzam for their time and efforts serving on the defense committee.\n\nMost importantly, I would like to thank my family. They have been there for me through the years of my life, and their love, encouragement and support have made all the difference.\nSet-Based Approach for XACML Evaluation and Analysis\n\nHussein Jebbaoui\n\nABSTRACT\n\nPolicy-based computing is taking an increasing role in governing the systematic interaction among distributed cloud and Web services. XACML has been known as the de facto standard widely used by many vendors for specifying access control policies. Accordingly, the size and complexity of XACML policies are significantly growing to cope with the evolution of web-based applications. This growth raised many concerns related to the efficiency of real-time decision process (i.e. policy evaluation) and the correctness of complex policies. This thesis is addressing both concerns through the elaboration of SBA-XACML, a novel set-based scheme that provides efficient evaluation and analysis of XACML policies. To the best of our knowledge, we are the first addressing both problems simultaneously. Our approach constitutes of elaborating (1) set-based language that covers all the XACML components and establish an intermediate layer to which policies are automatically converted, (2) policy evaluation module that provides better performance compared to the industrial standard Sun Policy Decision Point (PDP) and its corresponding ameliorations, and (3) policy analysis module that allows to detect flaws, conflicts and redundancies in XACML policies. Formal and practical experiments have been conducted on real-life and synthetic XACML policies in order to demonstrate the efficiency, relevance and scalability of our proposition. The experimental results explore that SBA-XACML evaluation of large and small sizes policies offers better performance than the current approaches, by a factor ranging between 2.4 and 15 times faster depending on policy size. Moreover, they show how SBA-XACML analysis module allows detecting access flaws, conflict and redundancy at policy and rule levels.\n\nKeywords: Web Services Security, Set-Based Algebra, XACML, Policy Evaluation, Policy Analysis, Real-Time Decision, Access Control\n# Table of contents\n\n<table>\n<thead>\n<tr>\n<th>Chapter</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>I - Introduction</td>\n<td>1</td>\n</tr>\n<tr>\n<td>1.1 Motivations and Problem Statement</td>\n<td>1</td>\n</tr>\n<tr>\n<td>1.2 Objectives</td>\n<td>5</td>\n</tr>\n<tr>\n<td>1.3 Contributions</td>\n<td>6</td>\n</tr>\n<tr>\n<td>1.4 Thesis Organization</td>\n<td>7</td>\n</tr>\n<tr>\n<td>II - Background</td>\n<td>9</td>\n</tr>\n<tr>\n<td>2.1 Introduction</td>\n<td>9</td>\n</tr>\n<tr>\n<td>2.2 Web Services</td>\n<td>10</td>\n</tr>\n<tr>\n<td>2.3 Information Security</td>\n<td>11</td>\n</tr>\n<tr>\n<td>2.4 Access Control</td>\n<td>13</td>\n</tr>\n<tr>\n<td>2.5 Web Service Security</td>\n<td>15</td>\n</tr>\n<tr>\n<td>2.6 XACML Description and Illustrative Example</td>\n<td>17</td>\n</tr>\n<tr>\n<td>2.6.1 XACML Evaluation and Authorization</td>\n<td>17</td>\n</tr>\n<tr>\n<td>2.6.2 XACML Policy Structure</td>\n<td>19</td>\n</tr>\n<tr>\n<td>2.6.3 Illustrative Example</td>\n<td>21</td>\n</tr>\n<tr>\n<td>2.7 Formal Description and Verification</td>\n<td>25</td>\n</tr>\n<tr>\n<td>2.7.1 Syntax and Semantics</td>\n<td>25</td>\n</tr>\n<tr>\n<td>2.7.2 Set Theory</td>\n<td>27</td>\n</tr>\n<tr>\n<td>2.7.3 Formal Verification</td>\n<td>29</td>\n</tr>\n<tr>\n<td>2.8 Related Work</td>\n<td>29</td>\n</tr>\n<tr>\n<td>2.8.1 Policy Evaluation</td>\n<td>30</td>\n</tr>\n<tr>\n<td>2.8.2 Policy Analysis</td>\n<td>32</td>\n</tr>\n<tr>\n<td>2.9 Conclusion</td>\n<td>35</td>\n</tr>\n<tr>\n<td>III - SBA-XACML Language and Evaluation</td>\n<td>36</td>\n</tr>\n<tr>\n<td>3.1 Introduction</td>\n<td>36</td>\n</tr>\n<tr>\n<td>3.2 Approach Overview and Architecture</td>\n<td>37</td>\n</tr>\n<tr>\n<td>3.3 SBA-XACML Language Description</td>\n<td>39</td>\n</tr>\n<tr>\n<td>3.3.1 SBA-XACML Based Policy</td>\n<td>40</td>\n</tr>\n<tr>\n<td>3.3.2 SBA-XACML Request</td>\n<td>44</td>\n</tr>\n<tr>\n<td>3.3.3 SBA-XACML Response</td>\n<td>45</td>\n</tr>\n<tr>\n<td>3.4 Policy Evaluation Semantics</td>\n<td>45</td>\n</tr>\n<tr>\n<td>3.4.1 Match Function</td>\n<td>46</td>\n</tr>\n</tbody>\n</table>\n### List of Figures\n\n<table>\n<thead>\n<tr>\n<th>Figure</th>\n<th>Title</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>XACML Policy Structure</td>\n<td>3</td>\n</tr>\n<tr>\n<td>2</td>\n<td>Web Service Architecture</td>\n<td>10</td>\n</tr>\n<tr>\n<td>3</td>\n<td>Access Control Architecture</td>\n<td>14</td>\n</tr>\n<tr>\n<td>4</td>\n<td>XACML Data Flow Diagram</td>\n<td>18</td>\n</tr>\n<tr>\n<td>5</td>\n<td>XACML Rule and Policy Combining Algorithms</td>\n<td>19</td>\n</tr>\n<tr>\n<td>6</td>\n<td>XACML Policy Language Model</td>\n<td>20</td>\n</tr>\n<tr>\n<td>7</td>\n<td>SBA-XACML Architecture</td>\n<td>37</td>\n</tr>\n<tr>\n<td>8</td>\n<td>Experimental Results on Real-World XACML Policies</td>\n<td>68</td>\n</tr>\n<tr>\n<td>9</td>\n<td>Synthetic Policy Evaluation</td>\n<td>69</td>\n</tr>\n<tr>\n<td>10</td>\n<td>Real Policy Evaluation</td>\n<td>69</td>\n</tr>\n<tr>\n<td>11</td>\n<td>Policy Conversion</td>\n<td>70</td>\n</tr>\n<tr>\n<td>12</td>\n<td>Synthetic Policy Evaluation with Policy Conversion</td>\n<td>71</td>\n</tr>\n<tr>\n<td>13</td>\n<td>Real Policy Evaluation with Policy Conversion</td>\n<td>71</td>\n</tr>\n<tr>\n<td>Table Number</td>\n<td>Description</td>\n<td>Page</td>\n</tr>\n<tr>\n<td>--------------</td>\n<td>------------------------------------------------------------------------------</td>\n<td>------</td>\n</tr>\n<tr>\n<td>1</td>\n<td>Match Function Semantics Rules</td>\n<td>46</td>\n</tr>\n<tr>\n<td>2</td>\n<td>Evaluation Semantics Rules of a Policy Rule</td>\n<td>47</td>\n</tr>\n<tr>\n<td>3</td>\n<td>Evaluation Semantics Rules of a Policy (RCA=Permit-Overrides)</td>\n<td>48</td>\n</tr>\n<tr>\n<td>4</td>\n<td>Evaluation Semantics Rules of a Policy (RCA=Deny-Overrides)</td>\n<td>49</td>\n</tr>\n<tr>\n<td>5</td>\n<td>Evaluation Semantics Rules of a Policy (RCA=First-Applicable)</td>\n<td>50</td>\n</tr>\n<tr>\n<td>6</td>\n<td>Evaluation Semantics Rules of a PolicySet (PCA=Permit-Overrides)</td>\n<td>51</td>\n</tr>\n<tr>\n<td>7</td>\n<td>Evaluation Semantics Rules of a PolicySet (PCA=Deny-Overrides)</td>\n<td>52</td>\n</tr>\n<tr>\n<td>8</td>\n<td>Evaluation Semantics Rules of a PolicySet (PCA=First-Applicable)</td>\n<td>53</td>\n</tr>\n<tr>\n<td>9</td>\n<td>Evaluation Semantics Rules of a PolicySet (PCA=Only-one-Applicable)</td>\n<td>54</td>\n</tr>\n<tr>\n<td>10</td>\n<td>Results of Semantics-Based Policy Evaluation</td>\n<td>65</td>\n</tr>\n<tr>\n<td>11</td>\n<td>Subset Function Semantics Rules</td>\n<td>74</td>\n</tr>\n<tr>\n<td>12</td>\n<td>Intersection Function Semantics Rules</td>\n<td>75</td>\n</tr>\n<tr>\n<td>13</td>\n<td>Rules of Access Flaw Detection Semantics</td>\n<td>76</td>\n</tr>\n<tr>\n<td>14</td>\n<td>Rules of Redundancy Detection Semantics</td>\n<td>77</td>\n</tr>\n<tr>\n<td>15</td>\n<td>Rules of Conflict Detection Semantics</td>\n<td>78</td>\n</tr>\n</tbody>\n</table>\nListings\n\n2.1 SOAP Request message without WS-Security ......................... 16\n2.2 SOAP Request message with WS-Security .......................... 17\n2.3 XACML Policy for a Bank Service Part I ........................... 22\n2.4 XACML Policy for a Bank Service Part II .......................... 23\n2.5 XACML Access Request ............................................. 24\n2.6 XACML Access Response ............................................. 25\n3.1 SBA-XACML Policy for a Bank Service ............................ 62\n3.2 SBA-XACML Access Request ....................................... 64\n3.3 SBA-XACML Response ............................................... 66\n4.1 SBA-XACML Policy for a Bank Service ............................ 84\nChapter One\n\nIntroduction\n\n1.1 Motivations and Problem Statement\n\nDistributed cloud and Web services are becoming very popular and constituting the primary techniques for data exchange between distributed systems and partners. However, they are still facing the risk of exploits due to the vast accessibility of these services over the Internet [2]. Moreover, critical services are emerging such as banking and other business transactions, which raise many security challenges. In this regard, policy-based computing is taking an increasing role in governing the systematic interaction among distributed services. Particularly, access control is the most challenging aspect of Web service security to determine which partner can access which service. Currently, an increasing trend is to declare policies in a standardized specification language such as XACML, the OASIS standard eXtensible Access Control Markup Language [18]. XACML has been known as the de facto standard widely used by many vendors for specifying access control policies. It has been emerged as alternative solution to the traditional way of embedding policy\nXACML is an XML-based standard for communicating and enforcing access control policies between services and servers [18]. The XACML based policy has complex structure partitioned into three layers as illustrated in Fig. 1: The top layer contains policy sets, the middle layer contains policies and the lower layer contains rules. Each of the three layers has its own target, which contains a set of subjects, resources and actions. Every policy set has a combining algorithm to make the final decision in case of a tie between its policies, and every policy has a combining algorithm to make the final decision in case of a tie between its rules. The PolicySet example illustrated in Fig. 1 contains one policy with three rules. The policy P1 (line 3) has a rule combining algorithm \"Permit-Overrides\". P1 is applicable to requests with Resource equal to ServiceA (line 6). Rule R1 (line 9) permits access to any request with Resource equal to ServiceA (line 14), Subject not specified and Action not specified. Rule R2 (line 19) permits access to requests with Resource equal to ServiceA (line 15), Subject equal to Joe (line 30) and Action not specified. Rule R3 (line 36) denies access to requests with Resource equal to ServiceA (line 42), Subject equal to Joe (line 47) and Action not specified. Any request for ServiceA will be allowed because rule R1 grants access to any request with Resource equal to ServiceA, while the remaining rules are disregarded. According to the current XACML engine [18], each request is submitted to the Policy Enforcement Point (PEP) that formulates it using XACML language. Consequently, the Policy Decision Point (PDP) checks at runtime the request with respect to the policy in order to determine access or deny decision. The final decision is enforced by the PEP. This whole process is referred to by policy evaluation.\nWith the growth of web-based applications, the size and complexity of XACML policies are significantly growing to cope with this evolution. Some real-life composed policies may nowadays embed hundreds and even thousands of rules. This growth raised many concerns related to the efficiency of real-time decision process and the correctness (i.e. flaw and conflict free) of complex policies. This thesis targets both problems. First, as aforementioned, XACML evaluation engine is responsible of verifying all the rules of all the participating policies, in addition to resolving their corresponding combining algorithms, in order to handle the decisions to the requests at runtime. Hence, enforcing large size XACML policies will decrease the efficiency of policy evaluation engine, and consequently may create performance bottleneck for the whole services. Several approaches [12,17,19,24] have been proposed to ameliorate the performance of policy evaluation process of the original\nXACML engine [18]. However, these propositions entail major modification on the Sun PDP architecture [18] and assumptions in terms of continuous policy loading and cumulative reception of all requests, which do not always hold in real world environment and limit their efficiency and usefulness. More details about these limitations are presented in Chapter Two, Section 2.8. Hence, decreasing the overhead of XACML evaluation process still constitutes a real challenge.\n\nSecond, the complex structure of XACML makes policies candidate for insertion of possible flaws, conflicts and redundancies between policies and rules. For instance, considering the PolicySet example in Fig. 1, both Rules R1 and R2 of policy P1 have same Resource ServiceA and effect \"Permit\", with no Action specified. R1 does not limit access to specific set of subjects, while R2 limits access to requests with Subject equal to \"Joe\", hence it is safe to say that R2 is a subset of R1. The policy combining algorithm is \"Permit-Overrides\". Based on the given policy specification, R1 and R2 may lead to access flaw because the generic rule R1 will always take precedence and be evaluated before the restricted rule R2. Therefore the response will be always given by R1 that grants access to any Subject, while R2 that limits the access to Subject \"Joe\" will be disregarded. This contradicts with an access control policy objective that should enforce the more restricted rule. Moreover, rules R2 and R3 may lead to conflict since they are exactly the same but with opposite effects. In this context, the current XACML tools give major role to security administrators for resolving some tie/conflict decisions through policies/rules modifications and/or combining algorithms (e.g. Permit- Overrides and First-Applicable). Although such manual remediation seems feasible for small scale policies, this is definitely problematic for large scale ones with hundreds and even thousands of policies and\nrules. The problem grows more when several XACML policies from different parties are integrated and composed together (e.g. in business process model and community of web services), where contractions between combining algorithms are also risen. In this regard, few approaches have been proposed addressing XACML policy composition and analysis [5, 8, 10, 16, 25, 31, 32]. However, these propositions did not address the aforementioned flaws and conflicts problems and are still missing some XACML elements such as rule conditions and obligations.\n\n1.2 Objectives\n\nThe main aim of this thesis is to provide an efficient solution for XACML analysis and real-time decision evaluation to cope with the growth of web applications and service in terms of size and complexity. The main corresponding objectives are:\n\n- Address the XACML complexity problem by elaborating an alternative language with standardized structure unlike XACML.\n\n- Elaborate an efficient evaluation approach for realtime decisions on XACML policy requests.\n\n- Provide a formal analysis method for detecting access control flaws, conflicts and redundancies during the creation phase of access control policies.\n1.3 Contributions\n\nIn this thesis, we address the aforementioned complexity, performance and analysis problems by elaborating a novel and complete formalization of XACML based on sets. Formal methods give advantages over other approaches because they provide a high level of assurance, which is a key factor for the security of critical services. The formal specification of policies and rules using sets is allowing us to efficiently perform evaluation and analysis tasks. To the best of our knowledge, we are the first targeting both concerns simultaneously. The proposed SBA-XACML scheme is composed of a formal language including an automatic converter and compiler, a policy evaluation module based on formal semantics, and a policy analysis module based on formal verification semantics. All the approach components have been implemented in one development framework that accepts XACML policies and requests as inputs, converts them automatically to SBA-XACML constructs when needed, performs analysis and reports the existence of flaws, and evaluates the requests and policies to provide the final access decision. The provided formal and practical experiments conducted on real-life and synthetic XACML policies explore the efficiency, relevance and scalability of our proposition for policy evaluation and security flaws detection. In this context, the main contributions of SBA-XACML and this thesis are three folds:\n\n- Set-Based intermediate representation of XACML constructs into readable mathematical syntax that maintain the same XACML policy structure and account for all its elements and their sub elements including rule conditions, obligations, policy request and policy response. The corresponding language and compiler offer automatic\nand optional conversion from XACML to SBA-XACML constructs.\n\n- Formal semantics and its implemented algorithms that take advantage of the mathematical operations to provide efficient policy evaluation. Unlike current literature, the adopted approach maintains the same architecture of the industrial standard XACML Sun PDP [18] and respects the major properties and assumptions of real-life environments in terms of remote policy loading upon need and disjoint reception of requests from distributed parties. The presented experimental results explore that SBA-XACML evaluation of large and small sizes policies has better performance than Sun PDP [18] and its corresponding ameliorations [12, 17, 19, 24].\n\n- Formal semantics and its implemented algorithms for XACML policy analysis that enable to detect access flaws, conflicts and redundancies at both policy and rule levels.\n\n### 1.4 Thesis Organization\n\nThe remaining of this thesis is organized as follows:\n\nIn Chapter Two, we present an introduction on the concepts of Web services, information security, access control, Web services security, XACML, Formal Description and Verification. Afterwards, we discuss some of the related works done in the area of XACML.\n\nIn Chapter Three, we describe the proposed SBA-XACML approach and language. First, we present the approach schema and architecture, the language syntax and semantics.\nThen, we state the algorithms for real-time decision evaluation. Finally, we share a study to show the effectiveness and results of our proposal with respect to other approaches.\n\nIn Chapter Four, we present the proposed SBA-XACML Analysis. First, we describe the policy analysis semantics. Then, we state the policy analysis algorithms. Finally, a complete case study is illustrated to demonstrate the usefulness our proposal.\n\nIn Chapter Five, we summarize the accomplishment, contributions, future work and list of publications gained from this thesis.\nChapter Two\n\nBackground\n\n2.1 Introduction\n\nThis chapter is devoted to several concepts used in our research. First, we present an overview about Web services, architecture and components. Second, we discuss the importance of Information security and its objectives. Third, we briefly explain the process of access control and its architecture. Fourth, we provide an overview of Web service security and a demonstration example. Fifth, we present the XACML description and an illustrative example. Sixth, we discuss the formal description and verification. Finally, we present an overview of the literature related to our work and their limitations.\n2.2 Web Services\n\nWeb services are very popular nowadays. They are the backbone of Internet. They provide the opportunity to shift away from highly coupled systems to more loosely dynamic systems. One outstanding advantage for web services is that they are application platform and technology independent. This advantage allows and encourages Web services-based applications to be freely joined with different components from different technologies. Web services fulfill a specific task or a set of tasks. They can be used alone or with other Web services to carry out a simple and complex transactions. Web services do not provide a graphical user interface for interaction with end users but instead it behaves as an API (Application Programming Interface) over the Web. Integration of Web services are fast, easy and cheap. Fig. 2 represents the architectural module of Web services.\n\nAs illustrated in Fig. refWeb Service Architecture, Web services are self-contained modular applications that can be described, published and invoked over the Web. They\nare discovered via the UDDI registry and described via the WSDL file. The WSDL file provides requesters with a set of operations and their definitions. Below is a list of the main processes:\n\n- **WSDL (Web Service Description Language)** is a file which contains the description of the web service operations it supports. This file is developed and published after the development of the Web service.\n\n- **UDDI (Universal Description, Discovery and Integration)** is a registry of all Web service’s meta-data including a pointer to the WSDL description of a service.\n\n- **Web service module** is the component for providing services.\n\n- **Service consumer** is the service requester.\n\nThe communications between service consumers and Web services are done through SOAP (Simple Object Access Protocol) messages. The messaging structure is in XML (eXtensible Markup Language). Web services are very flexible and easy to develop and deploy. A Web service can call another Web service. They enable access to information regardless of methods and devices.\n\n### 2.3 Information Security\n\nInformation security is the process of securing information from unauthorized access. Information security is concerned with data being transmitted from one host to another as well as the physical data which resides on a server or a drive. It is the prevention of any disclosure of information regardless of the state. In this thesis we are just concerned with\nonline information. There are several different methods which may cause theft, damage and disclosure to information. Some of the methods are: weak access control policies, malicious attacks, insiders, virus, etc.\n\nSecurity measures must be taking to protect assets against attacks regardless of their kind and state. Systems must be built with security measures from the start. Security is not something that can be added to an existing system, it must be designed as a part of the system from the start. Systems should be built to resist attacks but at minimum, a system should be able to recover in case of a successful attack. Any system with good information security if its data is never lost, damaged or disclosed. A successful attack can damage reputation, lost revenue and future businesses. Risk analysis should be considered to evaluate the existing system security and to correct any weaknesses and to apply the proper security measures to prevent future attacks. It is very important that businesses perform risk analysis to have a clear idea of where they stand with respect to security. Risk analysis provides a report of where the weaknesses are and the type of threats they may face. In addition, risk analysis gives an estimate of how much assets worth to be able to spend on securing them.\n\nInformation security is the protection of information related assets. The main objectives of information security are: confidentiality, integrity, availability, authenticity and accountability.\n\n- Confidentiality: prevent unauthorised disclosure of information.\n- Integrity: prevent unauthorised modification of information.\n- Availability: prevent unauthorised withholding of information or resources.\n• Authenticity: verify the identity of an entity or source of information.\n\n• Accountability: prove that an entity was involved in some actions\n\nInformation security is a wide topic but our focus in this thesis are the security issues which are related to Web services. Web services are fairly new technologies but many companies and agencies have been rushing in with many projects already been deployed and used in production. Web services are simple to build and deploy for data sharing and advertising. However, the security concerns are still the leading issue and the top investment areas for government agencies and companies.\n\n2.4 Access Control\n\nThe heavy reliance on Internet communications for data exchange, access control is a mandatory measure to ensure that unauthorized users do not gain access and maintain minimum access to authorized users to perform their duties. Access control is a critical security measure because it involves both computer scientists and engineers to provide proper security design and implementation. Access is not just about requiring a user name and password when users request access to resources, they are much more complex. There are multiple methods and technologies that can be implemented to support and administer access for different areas. Access control mechanisms are always changing to be able to resist against a variety of attacks.\n\nAn access control system monitors access requests and implements policies which establish who can, or cannot, execute which actions on which resources [28]. Its process is\npartitioned into three steps: identification, authentication and authorization. Identification is the step where the subject is identified to the requested service. Authentication is the second step of access control and it is the process of verifying the subject requesting the service. Authorization is the third step and it is determining the type of access to resources a subject can have. Fig. 3 shows a generic architectural module of access control.\n\nFig. 3 illustrates the different steps involved in the access control process. The first step is a user action entering a username and a password in a form. The second step takes place on the system which houses the credentials for user access. During this step, the authentication server matches both the username and password entered in the first step against an entry in the access database. If match found then the user is authenticated otherwise, access denied is returned. The third step is verifying the privileges of the user requesting access against the service requested. If the user’s access privilege is equivalent to the service’s requested then the user’s request is granted otherwise denied.\n\nAccess control is always evolving to address the security concerns to increase user confidence. It is shifting from the classical methods such as user name and pass phrases\ntowards biometrics. Biometric access control provides a higher level of securing access. The term 'biometrics' refers to a measurable characteristic that is unique to an individual such as fingerprints, facial structure, iris, etc.\n\n2.5 Web Service Security\n\nWeb service security has been in the research spotlight and its main concern is providing better security for Web services with the objectives of confidentiality and integrity. Many related standards have been proposed and used and many others in theory. The aim of these is to provide web services with more robust security mechanisms. Protections required for Web services at different layers as distributed applications because they face the same security risks such as SQL Injection, Cross-Site scripting, broken authentication, Missing Function Level Access Control, etc [13]. However, they are more vulnerable because they expose more sensitive data between partners.\n\nWeb services use SOAP messages for data exchange between two end points but SOAP does not provide a mechanism for ensuring data integrity or confidentiality either at rest or during transit. Its communication security remains a critical task to be tackled and a costly investment due to the complexity of securing Web services because their descriptions of how they work is made public over the Internet. One of the leading security standards for providing security at the message level for Web services is WS-Security (Web Service Security).\n\nWS-Security [1] is an extension to SOAP. It has been introduced and published by OASIS in order to apply security in Web Services through using existing standards and\nspecifications. WS-Security is not a stand alone solution for securing data exchange but it is a method that allows security standards to be used such as encryptions, digital signatures, etc. It supports whatever security related data to be defined in the header of the SOAP message. If XML Signature is used, the SOAP header can contain the Signature method, the key and the resulting signature value. Likewise, the header can contain the encryption information if any elements within the message are encrypted. WS-Security does not specify the format of the signature or encryption but instead, it specifies how one would embed the security information laid out by other specifications within a SOAP message. WS-Security is primarily a specification for an XML-based security meta-data container. The following is an example of SOAP to demonstrate the difference between secure and insecure messages.\n\nListing 2.1 shows a demonstration of SOAP messages without security applied [30]. Both username and password fields are inserted in plain text. In this case, anyone with a sniffer is easily able to capture the user and password without too much efforts.\n\nListing 2.1: SOAP Request message without WS-Security\n\n```xml\n<wsse:UsernameToken>\n <wsse:Username>scott</wsse:Username>\n <wsse:Password Type=\"wsse:PasswordText\">password</wsse:Password>\n</wsse:UsernameToken>\n```\n\nListing 2.2 shows a demonstration of SOAP messages with WS-Security applied [30].\n\nIt shows a SOAP message with WS-Security applied to the password. The username is sent in plain text but the password is encrypted. The password digest is a SHA1 algorithm hash based on the concatenation of the password, message creation time and a nonce. SHA1 algorithm is one of the many available encryption algorithms for security.\nListing 2.2: SOAP Request message with WS-Security\n\n```\n<wsse:UsernameToken>\n <wsse:Username>scott</wsse:Username>\n <wsse:Password Type=\"wsse:PasswordDigest\">KE6QugOpkPyT3Eo0SEgT30W4Keq</wsse:Password>\n <wsse:Nonce>5uW4ABku/m6/S5rnE+L7vg==</wsse:Nonce>\n <wsu:Created xmlns:wsu=\"http://schemas.xmlsoap.org/ws/2002/07/utility\">2002-08-19T00:44:02Z\n</wsu:Created>\n</wsse:UsernameToken>\n```\n\n2.6 XACML Description and Illustrative Example\n\nXACML (eXtensible Access Control Markup Language) [18] is the OASIS standard language for access control policies. XACML is the default access control for web services. Today, it is the most popular and well known access control mechanism. XACML is XML-based standard for communicating access control policies between services and provides XML schema for access control policies, requests and responses [9]. XACML is not just a standard for describing access control policy in XML but also is a complete application for evaluating any given request against a policy. We will discuss the XACML evaluation/authorization and the structure of access control policy. The XACML data flow is depicted in Fig. 4.\n\n2.6.1 XACML Evaluation and Authorization\n\nThe XACML Evaluation and Authorization contain five processes: Policy Enforcement Point (PEP), Policy Administration Point (PAP), Policy Decision Point (PDP), Policy Information Point (PIP), and a context handler [18].\n\nPAP: PAP is the repository for the policies and provides the policies to the PDP. PDP: The system entity which handles the evaluation and returns the authorization decision to PEP. PEP: The system entity that performs access control, by making decision requests and\nenforcing authorization decisions. PIP: The system entity that acts the attribute authority. Context handler: Handles the data conversion and communications between PDP, PEP and PIP.\n\nFig. 4: XACML Data Flow Diagram\n\nFig. 4 illustrates processes listed above and the information flow. PAP writes policies and makes them available to the PDP. The PEP receives the request and sends it to the context handler. The Context handler translates the request and sends it to the PDP for a decision. The PDP requests additional attributes from the context handler during the evaluation. The Context Handler collects these attributes by the help of the PIP from the resources, subjects, and the environment. The PDP sends the XACML Response to the Context Handler after the evaluation is finished. The Context Handler converts the response message and send to PEP. If there are any obligations to be fulfilled based on the\nauthorization decision, the PEP handles them.\n\n### 2.6.2 XACML Policy Structure\n\nXACML access policy is ordered into 3 levels: `<PolicySet>`, `<Policy>` and `<Rule>`. Every level in the policy has a target. The target element is used to determine whether the `<PolicySet>`, `<Policy>` or `<Rule>` is applicable to the request. If the target does not match then NotApplicable is returned. The `<PolicySet>` element contains a set of `<Policy>` elements and a Policy Combining Algorithm (PCA) used for combining the results of the evaluation of individual policies. The `<Policy>` element contains a set of `<Rule>` elements and a Rule Combining Algorithm (RCA) used for combining the results of the evaluation of individual rules. The Combining Algorithm works the same way at the policy and rule levels. Fig. 5 illustrates the Combining Algorithms for both Policy and rule levels.\n\n<table>\n<thead>\n<tr>\n<th>Combining Algorithm</th>\n<th>Behavior Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Deny-Overrides</td>\n<td>If a single rule or policy evaluates to Deny then regardless of the others the end result is “Deny”.</td>\n</tr>\n<tr>\n<td>Permit-Overrides</td>\n<td>If a single rule or policy evaluates to Permit then regardless of the others the end result is “Permit”.</td>\n</tr>\n<tr>\n<td>First-Applicable</td>\n<td>The end result is the result of the first applicable rule or policy.</td>\n</tr>\n<tr>\n<td>Only-one-Applicable</td>\n<td>Applies only at the policy level. If one and only one policy is applicable then the end result is the evaluation result of the applicable policy. If more than one policy is applicable then the end result is “Indeterminate”. If no policies are applicable then the end result is “NotApplicable”.</td>\n</tr>\n</tbody>\n</table>\n\nFig. 5: XACML Rule and Policy Combining Algorithms\n\nThe `<PolicySet>` and `<Policy>` elements can have reference to other policies. They can\nhave obligations to fulfill whenever the decision is either permit or deny. A rule is the most elementary in the access policy. The main components of a rule are target, condition that are represented by subelements and effect which is included as an attribute of the Rule element. The condition attribute is a boolean function over subjects, resources and actions. If the conditions evaluate to true then the rule effect is returned otherwise NotApplicable is returned. Fig. 6 presents the policy language model.\n\n![Policy Language Model Diagram]\n\n**Fig. 6: XACML Policy Language Model**\n\nFig. 6 shows the policy structure and the relationship between the individual elements. The <PolicySet> element has a target, a Policy Combining Algorithm, a set of Policies and a Set of obligations. The <Policy> element has a target, a Rule Combining Algorithm, a set of Rules and a Set of obligations. The <Rule> element has a target, a rule effect, and a set of Conditions. The Target element is based on a set of subjects, resources and actions.\nXACML is a well known mechanism for access control especially for Web applications and Web services. It supports business specific customizations. It is very flexible but it is very complex at the same time. It supports dynamic access control with policies applied at runtime but still has its disadvantages. As of a result of its complexity, it is hard to analyze in order to determine if any flaws exists in the based policy. Its richness in expressions makes it harder to create standardized tools for examining for conflicts, access flaws and redundancies. In addition, integrating multiple XACML policies is a nightmare.\n\n2.6.3 Illustrative Example\n\nIn this section, we provide an XACML based policy, request, and response of the evaluation process according to XACML syntax and Sun PDP engine [18]. We will adopt this example throughout the thesis. A based policy for a Bank service is presented in listing 2.3 and listing 2.4. The policy set contains two policies $P_1$ and $P_2$. $P_1$ contains two rules $R_1$ and $R_2$. It has a rule combining algorithm permit – overrides. $R_1$ permits access to BankService/withdraw resource if the subject is Bob. $R_2$ denies access to any resources for any subjects. If policy $P_1$ evaluates to permit, it has an obligation to send an email to Customer_service@bank.com. $P_2$ contains three rules $R_3$, $R_4$ and $R_5$. It has a rule combining algorithm permit – overrides. $R_3$ permits access to BankService/deposit resource for any subjects. $R_4$ permits access to BankService/deposit resource if the subject is Joe. $R_5$ denies access to BankService/deposit resource if the subject is Joe.\n\nThe policy set ID and policy combining algorithm PCA are stated in line 3. Lines 4 to 51 contain the policy $P_1$. The rule combining algorithm RCA is permit – overrides (line\nListing 2.3: XACML Policy for a Bank Service Part I\n\n```\n<PolicySet xmlns=\"schema:os\" PolicyCombiningAlgId=\"policy-combining-algorithm:permit-overrides\" PolicySetId=\"PS1\">\n <Policy PolicyId=\"P1\" RuleCombiningAlgId=\"rule-combining-algorithm:permit-overrides\">\n <Target>\n <Subjects>\n <Subject>\n <SubjectMatch MatchId=\"function:string-equal\">\n <AttributeValue DataType=\"xml:string\">Jerry</AttributeValue>\n </SubjectMatch>\n <SubjectMatch MatchId=\"urn:oasis:names:tc:xacml:1.0:function:string-equal\">\n <AttributeValue DataType=\"xml:string\">Bob</AttributeValue>\n </SubjectMatch>\n </Subject>\n </Subjects>\n <Resources>\n <Resource>\n <ResourceMatch MatchId=\"function:string-equal\">\n <AttributeValue DataType=\"xml:string\">BankService/withdraw</AttributeValue>\n </ResourceMatch>\n </Resource>\n </Resources>\n <Actions>\n <AnyAction />\n </Actions>\n </Target>\n <Rule Effect=\"Permit\" RuleId=\"R1\">\n <Condition>\n <Apply FunctionId=\"function:and\">\n <Apply FunctionId=\"function:string-equal\">\n <ResourceAttributeDesignator AttributeId=\"resource:resource-id\" DataType=\"xml:string\">BankService/withdraw</ResourceAttributeDesignator>\n </Apply>\n <Apply FunctionId=\"function:string-equal\">\n <SubjectAttributeDesignator AttributeId=\"subject:subject-id\" DataType=\"xml:string\">Bob</SubjectAttributeDesignator>\n </Apply>\n </Apply>\n </Condition>\n </Rule>\n <Rule Effect=\"Deny\" RuleId=\"R2\" />\n <Target/>\n <Obligations>\n <Obligation FulfillOn=\"Permit\" ObligationId=\"Withdraw\">\n <AttributeAssignment AttributeId=\"example:attribute:mailto\" DataType=\"xml:string\">Customer_service@bank.com</AttributeAssignment>\n <SubjectAttributeDesignator AttributeId=\"subject:subject-id\" DataType=\"xml:string\">subject:subject-id</SubjectAttributeDesignator>\n <ResourceAttributeDesignator AttributeId=\"resource:resource-id\" DataType=\"xml:string\">resource:resource-id</ResourceAttributeDesignator>\n </Obligation>\n </Obligations>\n </Policy>\n</PolicySet>\n```\n4. Lines 5 to 29 is the policy target. Subjects equal to Jerry and Bob specified in lines 9 and 13. Resource BankService/withdraw is defined in line 21. Actions are defined to be any in line 27. Policy P1 contains two rules R1 and R2. Rule R1 starts in line 30 and ends in line 41. R1 has a permit rule effect. The rule conditions are the subject = Bob and resource = BankService/withdraw in lines 34 and 37 respectively. R2 defined in line 42. Deny anything to anyone. Policy P1 has an obligation to perform if the policy evaluates to permit. Obligations are defined in lines 44 to 50. The policy P2 starts in lines 51 to 85. It contains three rules R3, R4 and R5. The RCA of P2 is permit − overrides.\nand is listed in line 52. No Target is defined for $P_2$. $R_3$ starts in line 54 and ends in line 60 with rule effect equal \\textit{permit}. $R_3$ has one condition, which is the resource id must match \\textit{BankService/deposit}. Rule $R_4$ starts in line 61 and ends in line 72 with rule effect equal \\textit{permit}. $R_4$ conditions are that the resource id which must match \\textit{BankService/deposit} and subject id \\textit{Joe}. Rule $R_5$ starts in line 73 and ends in line 84 with rule effect equal \\textit{Deny}. $R_5$ conditions states that the resource id must match \\textit{BankService/deposit} and subject id \\textit{Joe}.\n\nListing 2.5 contains the XACML request. The request is calling for a resource \\textit{BankService/deposit} with a subject \\textit{Bob} and action \\textit{execute}. Lines 4, 9 and 14 contain subject, resource and action respectively.\n\n\\begin{verbatim}\nListing 2.5: XACML Access Request\n\n[1]. <Request xmlns=\"context:schema:os\" xmlns:xsi=\"XMLSchema-instance\">\n[2]. <Subject SubjectCategory=\"subject-category:access-subject\">\n[3]. <Attribute AttributeId=\"subject:subject-id\" DataType=\"xml:string\">\n[4]. <AttributeValue>Bob</AttributeValue>\n[5]. </Attribute>\n[6]. </Subject>\n[7]. <Resource>\n[8]. <Attribute AttributeId=\"resource:resource-id\" DataType=\"xml:string\">\n[9]. <AttributeValue>BankService/deposit</AttributeValue>\n[10]. </Attribute>\n[12]. <Action>\n[13]. <Attribute AttributeId=\"action:action-id\" DataType=\"xml:string\">\n[14]. <AttributeValue>execute</AttributeValue>\n[15]. </Attribute>\n[16]. </Action>\n[17]. </Request>\n\\end{verbatim}\n\nListing 2.6 contains the XACML response to the request in Listing 2.5 against the based policy in listing 2.3 and listing 2.4. The response is the final decision for the resource \\textit{BankService/deposit} with a subject \\textit{Bob} and action \\textit{execute}. \n\n24\n### Listing 2.6: XACML Access Response\n\n```xml\n[1]. <Response>\n[2]. <Result ResourceID=\"BankService/deposit\">\n[3]. <Decision>Permit</Decision>\n[4]. <Status>\n[6]. </Status>\n[7]. </Result>\n[8]. </Response>\n```\n\n## 2.7 Formal Description and Verification\n\nA formal description consists of strings, symbols and rules forming a language. It is called formal because it is based on mathematical notations. The strings and symbols are grouped together according to a set of rules which are defined specifically for the language. A formal description language includes both language syntax and semantics. We use such languages to express rules and perform formal verification. In this section, we describe each of these components.\n\n### 2.7.1 Syntax and Semantics\n\nLanguage Syntax provides the structure of how strings and symbols are combined together according to the certain rules without any considerations to their meanings. Formal semantics constitutes of rigorous mathematical study of the meaning of languages and models of computation [22, 26]. It allows to prove the properties of a program. The formal semantics of a language is specified by a mathematical model that illustrates the possible computations described by the language. There are many approaches to formal semantics that belong to three major classes: Operational semantics, denotational semantics and axiomatic semantics. These three classes are presented in the increasing order of abstraction with respect to the concepts of meaning underlying them. The following is a brief\ndescription for each one of them:\n\n- Operational semantics describes the execution of the language directly rather than by translation. It somehow corresponds to interpretation, where the implementation language of the interpreter is a mathematical formalism. The operational semantics may define an abstract machine and give meaning to the transitions between its states. It may also be defined via syntactic transformations on phrases of the language itself.\n\n- Denotational semantics translates each phrase in the language to another phrase in another language. It somehow corresponds to compilation, where the target language is a mathematical formalism.\n\n- Axiomatic semantics gives meaning to phrases by expressing the logical axioms that apply to them. Axiomatic semantics does not distinguish between a phrase meaning and the logical formulas describing it. A phrase means exactly what can be proven about it in some logic.\n\nSince this thesis presents an operational semantics for XACML policies evaluation and analysis, in the sequel we elaborate more about this approach and introduce the used structural operational semantics. Operational semantics is considered as a method to give meaning to programs and operations in a mathematically rigorous way. It describes how a valid process is interpreted as sequences of computational steps, which then constitute the meaning of the whole process. The final step in the terminating sequence returns the value of the process in the case of a functional process. A process could be also nondeterministic, in this context there may be many computation sequences and many return values.\nStructural operational semantics is an approach proposed to give logical means in defining operational semantics [23]. It consists of defining the behavior of a process in terms of the behavior of its parts. Hence, it provides a structural, a syntax oriented and an inductive view on operational semantics. Computation is represented by means of deductive systems that turn the abstract machine into a system of logical inferences. This allows to apply formal analysis on the behavior of processes. The proofs of process properties are derived directly from the definitions of the language constructs because the semantics descriptions are based on deductive logic. With structural operational semantics, the behavior of a process is defined in terms of a set of transition relations. Such specifications take the form of inference rules. The valid transitions of a composite piece of syntax is defined into these rules in terms of the transitions of its components. Definitions are given by inference rules, which consist of a conclusion that follows from a set of premises, possibly under control of some conditions. An inference rule has a general form consisting of the premises listed above a horizontal line, the conclusion below, and the condition, if present, to the right, as follows [26]:\n\n\\[\n\\frac{\\text{premise}_1 \\quad \\text{premise}_2 \\quad \\ldots \\quad \\text{premise}_n}{\\text{conclusion}}\n\\]\n\nIf \\( n=0 \\), i.e., the number of premises is zero, then the line containing the premises is omitted, and we refer to the rule as an axiom.\n\n2.7.2 Set Theory\n\nSet theory is the study of sets. A set is a group of items known as elements [4]. When describing a set in Mathematics, all of its elements are listed in a row separated by commas\nand enclosed with curly braces. The name of sets are usually presented in upper case.\n\nFor example, a set S containing the elements 1, 4, 2, 8 and 9 could be shown as follows: S = \\{1, 4, 2, 8, 9\\}. An element e in a set S is expressed in Mathematical notation: e ∈ S. The symbol ∈ in set notation means is a member of. Any set S is a subset of itself and expressed as S ⊆ S. The symbol ⊆ in set notation means a subset or equal.\n\nA set can contain no elements. This type of sets is referred to as an empty set or null set and is denoted by the symbol ∅. An empty set is a subset of any set. A set A is a subset of a set B if every element in A is an element in B. It can be written as A ⊆ B to designate such relationship, but if the set B contains elements which are not in the set A then we can say that A is a proper set of B and it is written as A ⊂ B. Two sets A and B are equal if A ⊆ B and B ⊆ A. If the two sets A and B are equal, we write A = B to designate the equality relationship.\n\nOperations which are performed on sets include union, intersection, cartesian product, etc. A union is a Mathematical operation for sets and it is denoted by the symbol ∪. The union of two sets is another set whose elements include the members of each original set. The common elements between the two sets are only counted once. For example, a set A = \\{1, 2, 3\\} and a set B = \\{7, 2, 8\\}. A ∪ B = \\{1, 2, 3, 7, 8\\}. An intersection is a Mathematical operation for sets and it is denoted by the symbol ∩. The intersection of two sets is another set whose elements are the common the elements of the two original sets. If the original two sets share no elements then the intersection of the two is the empty set. For example, a set A = \\{1, 2, 3\\} and a set B = \\{7, 2, 8\\}. A ∩ B = \\{2\\}. A cartesian product is a Mathematical operation and it is denoted by the symbol ×. A cartesian product of two sets returns a product set from the two sets. That is, for sets A and B, the Cartesian product A × B is the\nset of all ordered pairs $a, b$ where $a \\in A$ and $b \\in B$. For example, a set $A = \\{1,2\\}$ and a set $B = \\{7,8\\}$. $A \\times B = \\{1,7,1,8,2,7,2,8\\}$.\n\n### 2.7.3 Formal Verification\n\nThe main purpose of providing a formal description is to perform formal verification on the described entity with respect to specific properties [7]. In other words, formal verification is a mathematical method which focuses on verifying the correctness of a system with respect to a set of specifications or properties. This process provides an opportunity to test and correct defects in the early phases of the development cycle. It has been increasingly used in the development of critical systems such as traffic lights, air traffic control, banking systems, etc. They have many advantages in providing higher quality and accuracy. However, they have few disadvantages such as difficult for unknowledgable personnel, expensive and time consuming. There are many methods for formal verification such as Process Algebra, Petri Nets, Temporal Logic and Finite State Machine, etc.\n\n### 2.8 Related Work\n\nOur approach is targeting both XACML policy evaluation and analysis. To the best of our knowledge, we are the first proposing a scheme for efficient policy evaluation, which offers simultaneously policy analysis mechanisms for flaws and conflicts detection. In this context, we provide in this section an overview of the related work in the literature addressing both problems independently.\n2.8.1 Policy Evaluation\n\nRegarding policy evaluation, several approaches have been proposed to provide efficient evaluation process. Liu et al. [12] proposed the XEngine which is a scheme for efficient XACML policy evaluation. It is an extension to the SUN Policy Decision Point (PDP) [18]. Their approach improves the performance of the PDP by numericalization and normalization of the XACML Policies. It consists of 3 steps. The first one is the conversion process of all the strings of XACML based policy and requests to numerical values. The second one is the normalization process which is the conversion of the output from the first step to hierarchical structure and conversion of combining algorithm to First-applicable. The third step is creating a tree structure from the second one. Their approach provides amelioration with respect to policy evaluation performance. However, they do not support obligations due to the conversion of all combining algorithms to first applicable [19]. Moreover, the major modification on the Sun PDP architecture and main assumptions of their experiments do not always hold in real world environment, which limit the efficiency and usefulness of their proposition. First, assuming that the policies are always loaded in the memory contradicts with the core concept of XACML [18] and is problematic for large size policies with hundreds and thousands of rules. The policies should be loaded upon request for a short period, where the policy repository can be accessed locally or remotely for security, privacy and memory restriction purposes. Second, our experiments with their tools show that the main overhead reduction is achieved when all the requests (i.e. up to 100,000 requests) are received, converted and loaded in the memory at the same time, then all of them evaluated against the already loaded policies. Again, such assumption does not always hold since\nrequests can be received from different parties at variant time-space. In this regard, the\nprovided experimental results explore that our approach provides better performance than\nXEngine.\n\nMarouf et al. [17] proposed a clustering and re-ordering techniques for optimizing\nXACML performance. The proposed clustering method groups policies and rules based\non target subjects. The re-ordering process is based on statistical analysis of policy and\nvibrant stream of requests. This process reduces the evaluation time because applicable\npolicies and rules are given higher priority to be evaluated first. Although this approach\nseems interesting, the assumption of access requests following a consistent distribution and\npolicy re-ordering does not support obligations. Moreover, they share the same limitations\nas XEngine in [12] in terms of major modification to Sun PDP architecture and experiments\nassumptions. The provided results show that our approach offers better performance based\non their experiments in [17].\n\nNgo et al. [19] proposed Multi-Data-Types Interval Decision Diagrams for XACML\nEvaluation Engine. Their approach is based on data interval partition aggregation along\nwith new decision diagram combinations. They claim that their proposed approach does not\nonly improve the evaluation response time, but also provides correctness and completeness\nof evaluation. Their proposed approach seems interesting, however it is only experimented\non small scale policies up to 360 rules, unlike our and other approaches [12, 17].\n\nPina Ros et al. [24] proposed an optimization for XACML policies evaluation based\non two trees. The first tree is a matching tree which is created for a quick finding of\napplicable rules. The second tree is a combining tree which is used for evaluation of the\napplicable rules. They proposed a binary search algorithm for finding the matching tree.\nThis approach supports requests with multi-valued attributes, however the matching tree\ndoes not support policies with multi-valued attributes.\n\nBased on the study of the current literature with respect to policy evaluation perfor-\nmance, it is trivial that this domain is still and will continue to be a challenging niche for\nresearchers. Our approach differs from the aforementioned ones in different aspects. First,\nit is maintaining the same policy structure of XACML and architecture of Sun PDP, where\npolicies are converted into intermediate mathematical and readable syntax. This allowed us\nto benefit from the formal description for efficient policy evaluation and analysis purposes.\nSecond, unlike all the current approaches, our scheme is respecting the major properties\nand assumptions made by Sun PDP [18] with respect to real-life environment, where poli-\ncies are loaded from local or remote location upon need, and the XACML requests are\nreceived one at a time from distributed parties. Third, our experiments in section 3.6 show\nthat our proposition outperforms the current approaches.\n\n2.8.2 Policy Analysis\n\nMoving to policy analysis, several approaches have been proposed in this regard. Kolovski\net al. [10] proposed a formalization of XACML using description logics (DL), which are\na decidable fragment of First-Order logic. They perform policy verification by using the\nexisting DL verifiers. Their analysis service can discover redundancies at the rule level.\nA rule is redundant if its decision is always overridden by other rules higher up. This\napproach may also speed up the evaluation process by removing rules that do not affect\nthe final decision. However, they do not address access flaws and conflicts and do not\nsupport multi-subject requests, complex attribute functions, rule Conditions and Only-One-Applicable combining algorithm.\n\nFisler et al. [8] proposed a suite called Margrave. It verifies whether an access control policy satisfies a given property and computes the semantic difference of two XACML policies. Margrave can perform a change-impact analysis on the policy to determine the impact of changing one or more rules on the whole policy. However, their proposal does not address policy analysis with respect to access flaws, conflicts and redundancies, and does not work on all types of XACML policies.\n\nTschantz et al. [31] present a set of properties for examining the reasonability of access control policies under enlarged requests, policy growth, and policy decomposition. Their approach focuses on the request and corresponding response behavior under different circumstances and policy reasoning for scalability. However, their they do not address policy analysis with respect to access flaws, conflicts and redundancies.\n\nMazzoleni et al. [16] proposed an authorization technique for distributed systems with policies from different parties. Their approach is based first on finding similarities between policies from different parties based on requests. Then, it provides an XACML extension by which a party can provide the integration preferences. This approach focuses on policy integration from different parties and do not address policy analysis for flaws, conflicts and redundancy existence.\n\nBertino et al. [25] introduced an algebra for fine-grained integration that supports specification of a large variety of integration constraints. They introduced a notion of completeness and prove that their algebra is complete with respect to this notion. Then, they proposed a framework that uses the algebra of fine-grained integration of policies expressed\nin XACML. Their approach, however, does not cover rule conditions and obligations and focuses on integration between different parties, unlike ours which focuses on analyzing policy sets individually and after integration. Moreover, they mention that there are no guarantees to know if the algebraic expression will hold as expected.\n\nWijesekera et al. [32] have proposed algebra for manipulating access control policies at a higher level, where the operations of the algebra are abstracted from their specification details. This algebra is motivated by discretionary and role based access control. However, they do not address XACML and do not provide implementation for their algebra.\n\nBonatti et al. [5] introduced the concept of policy composition under constraints, which aims at combining authorization specifications originating from different independent parties. They proposed algebra for composing access control policies using a variable free authorization terms which are subject, object and action. They suggest logic programming for implementation. However, this approach focuses on policy composition from distributed parties and do not target XACML.\n\nOur approach differs from the aforementioned ones in different aspects. First, it is providing a set-based algebra syntax and semantics that accounts for all the XACML elements, including rules conditions and obligations. Second, it is allowing us to provide a policy analysis framework for detecting different kind of flaws and conflicts in XACML policies, which are not yet addressed by the current propositions. Third, in addition to the analysis features, the elaborated algebra is offering us the capabilities to build efficient policy evaluation scheme.\n2.9 Conclusion\n\nIn this chapter, we presented an overview of Web services, Information Security, Access Control, Web services security and XACML. We also introduced the formal verification concept and its importance. Finally, We summarised the literature related work around XACML and their limitations.\nChapter Three\n\nSBA-XACML Language and Evaluation\n\n3.1 Introduction\n\nAccess control is widely used in Web applications and Web services. It maintains the control of which principle (user or process) has access to which resources in a system and its policies are written in specification language such as XACML [18]. Today, XACML is most used access control mechanism for Web services. However, with the growth of web-based applications, the size and complexity of XACML policies are significantly growing to cope with this evolution. This growth raised many concerns related to the efficiency of real-time decision process. We proposed a set based language to simplify the complexity and increases the responses time for real-time evaluation.\n\nThe rest of the chapter is organized as follows. Section 3.2 gives an overview of the approach and architecture. Section 3.3 describes the SBA-XACML language and its components. Section 3.4 provides the formal semantics for policy evaluation. Section 3.5 details the evaluation algorithms. Section 3.6 provides the policy evaluation and performance\nanalysis. Finally, Section 3.7 concludes the chapter.\n\n### 3.2 Approach Overview and Architecture\n\nIn this section, we present the overall architecture of our approach illustrated in Fig. 7.\n\n\n\nFig. 7: SBA-XACML Architecture\n\nOur proposition includes the SBA-XACML Language, Compiler, Evaluation Module and Analysis Module. All the approach components have been implemented in one development framework that accepts XACML policies and requests as inputs, convert them to SBA-XACML when needed, and perform systematically and automatically all the analysis and evaluation processes. It may also accepts already converted or written SBA-XACML policies and requests. Using the framework, the user can analyse the policies for security flaws and get the corresponding analysis report using the module embedding the analysis\nalgorithms. He can also evaluate the requests and get the corresponding responses using the module embedding the evaluation algorithms.\n\n**SBA-XACML Language & Compiler:** SBA-XACML is a formal language based on sets and composed of all the elements and constructs needed for the specification of XACML based policy, request and response. Sections 3.3 presents the complete definition and syntax of SBA-XACML elements and attributes. SBA-XACML compiler includes XACML parser and converter to SBA-XACML. It takes XACML policy set and request as inputs, parses their XACML elements and generates SBA-XACML constructs according to the language syntax and structure. The compiler is implemented using PHP (PHP Hypertext Preprocessor). It can be used independently to convert XACML to SBA-XACML, or as embedded in our framework with the policy evaluation and analysis modules to convert XACML to SBA-XACML at run time.\n\n**Policy Evaluation Module:** This module allows to evaluate a SBA-XACML request against a set of SBA-XACML policies. It is composed of policy-level and rule-level evaluation algorithms (see Section 3.5) that realize the elaborated policy evaluation semantics presented in Section . The policy-level algorithm is responsible for evaluating the policies and triggers the rule-level one in order to evaluate the rules in each policy. It is implemented in PHP and accepts as inputs a SBA-XACML request and a policy set.\n\n**Policy Analysis Module:** This module allows to analyse policies for detecting access control flaws, conflicts and redundancies. It is composed of policy-level and rule-level analysis algorithms that realize the elaborated analysis semantics both presented in Section\n4.3. The policy-level algorithm is responsible for analysing policies and triggers the rule-level one in order to analyze the rules in each policy. The analysis module works effectively if scheduled as a trigger on the repository to run whenever any modification is performed on policies. It can be scheduled to run in parallel with the evaluation module as well. It is implemented in PHP and accepts as input a policy set.\n\n### 3.3 SBA-XACML Language Description\n\nA Set is an accumulation of distinct mathematical elements that describes the fundamental characteristics and includes the regulations of sets and other operations such as union, intersections, complementation, equality and inclusion. It additionally provides systematic procedures for evaluating expressions and performing calculations, involving these operations and relations. SBA-XACML is a Set-based language. In this following, we present its constructs, operators and structure: \\((PS; P (R; Rq); Rs \\(\"Permit\"; \"Deny\"; \"NotApplicable\"; \"Indeterminate\")); op (\\(\\subseteq; \\subset; \\land; >; \\lor; \\cap))\\), where\n\n- \\(PS\\) : represents a policy set (or based policy) which is composed of one or more policies.\n - \\(P\\) : represents a policy which is composed of one or more rules.\n - \\(R\\) : represents a rule.\n - \\(Rq\\) : represents a request.\n - \\(Rs\\) : represents a response that contains the final decision.\n• \"Permit\", \"Deny\", \"NotApplicable\" and \"Indeterminate\" are policy constants and represent the final decision embedded in the response.\n\n• $op$ : represents an operator.\n\n - $\\subseteq$ : represents a subset or equal.\n - $\\subset$ : represents a subset.\n - $\\land$ : represents logical operator \"and\".\n - $\\lor$ : represents logical operator \"or\".\n - $>$ : represents the precedence order between operations.\n - $\\cap$ : represents the intersection between two sets.\n\nIn sections 3.3.1, 3.3.2 and 3.3.3, we present the SBA-XACML syntax for the based policy, request and response respectively.\n\n3.3.1 SBA-XACML Based Policy\n\nXACML based policy which they also refer to as a policy set $PS$, is ordered into 3 levels: $PolicySet$, $Policy$, and $Rule$. Every element can contain a $Target$. $PolicySet$ element contains other $PolicySet(s)$ and/or $Policy(s)$. $Policy$ contains $Rule(s)$. $PolicySets$ and $Policies$ have their $Obligations$ to fulfill whenever a $Response$ is reached to either a $Permit$ or $Deny$ decision. In the sequel, we present the definitions and syntax of all the elements.\n3.3.1.1 Common Elements Definitions and Syntax\n\nThe following are the common elements that are used at the policy set, policy and rule levels.\n\nA target $TR$ is an objective and is mapped to SBA-XACML within the context of rule, policy and policy set according to the following syntax:\n\n$$TR = \\{S, R, A\\}$$\n\n(Construct 1)\n\nwhere $S$ is a set of subjects, $R$ is a set of resources and $A$ is a set of actions.\n\nObligations $OBLs$ contain one or more obligation(s) $OBL$. An obligation is an action that takes place after a decision has been reached to either Permit or Deny. It is mapped to SBA-XACML within the context of policy and policySet according to the following syntax:\n\n$$OBLs = OBL – Set$$\n\n(Construct 2)\n\n$$OBL = \\{OBLID, FFOn, \\{\\{AttID, DT, V\\}\\}\\}$$\n\n(Construct 3)\n\nwhere $OBL – Set$ is the the set of obligation $OBL$ to be performed, $OBLID$ is the id identifying the obligation, $FFOn$ is the Fulfill On attribute which is used as a key to determine when the obligation must be enforced and it must be either permit or deny, $AttID$ is the attribute id of the obligation to be carried out, $DT$ is the data type and $V$ is the value. If the policy or policy set being evaluated matches the $FFOn$ attribute of its obligations then the obligations are passed to be enforced otherwise obligations are ignored.\n3.3.1.2 PolicySet (PS) Definition and Syntax\n\nA PolicySet $PS$ is a container of policies. $PS$ may contain other policy sets, policies or both. It can also be referenced by other policy sets. It is mapped to SBA-XACML according to the following syntax:\n\n$$PS ::= \\langle ID, SP, PR, PCA, IPS, OBLs, TR \\rangle$$\n\n(Construct 4)\n\nwhere $ID$ is the policy set id, $SP$ is the set of policies that belongs to policy set $PS$, $PR$ is the precedence order of policies that belongs to $PS$, $PCA$ is the policy combining algorithm, $IPS$ is the policies or policy set that are referenced by $PS$, $OBLs$ is the set of obligations (refer to Section 3.3.1.1 for details) and $TR$ is the target (refer to Section 3.3.1.1 for details).\n\nExample 1: Consider a policy set $PS1$ with two policies $P1$ and $P2$. $PS1$ has a $PCA = deny – overrides$. $PS1$ has a target $subject = Bob$, $resource = FileA$ and $action = Read$. It has no reference to other policies and no obligations. The policy set $PS1$ is mapped to SBA-XACML as follows:\n\n$$PS ::= \\langle PS1, \\{P1, P2\\}, \\{P1 > P2\\}, \\{deny – overrides\\}, \\{\\}, \\{\\}, \\{\\{Bob\\}, \\{FileA\\}, \\{Read\\}\\} \\rangle$$\n\n3.3.1.3 Policy (P) Definition and Syntax\n\nA policy $P$ is a single access control policy. It is expressed through a set of rules. A policy contains a set of rules, rule combining algorithm, target and obligations. It is mapped to SBA-XACML according to the following syntax:\n\\[ P ::= < ID, SR, PR, RCA, OBLs, TR > \\] \n\n(Construct 5)\n\nwhere \\( ID \\) is the policy id, \\( SR \\) is the set of rules that belongs to policy \\( P \\), \\( PR \\) is the precedence order of rules that belongs to \\( P \\), \\( RCA \\) is the rule combining algorithm, \\( OBLs \\) is the set of obligations (refer to Section 3.3.1.1 for details) and \\( TR \\) is the target (refer to Section 3.3.1.1 for details).\n\nExample 2: Consider a policy \\( P_1 \\) with two rules \\( R_1 \\) and \\( R_2 \\). \\( P_1 \\) has a \\( RCA = \\text{permit} - \\text{overrides} \\), a \\( \\text{target subject} = \\text{Bob} \\), \\( \\text{resource} = \\text{FileA} \\) and \\( \\text{action} = \\text{write} \\) and without any obligations. The policy \\( P_1 \\) is mapped to SBA-XACML as follows:\n\n\\[ P ::= < P_1, \\{ R_1, R_2 \\}, \\{ R_1 > R_2 \\}, \\{ \\text{permit} - \\text{overrides} \\}, \\{ \\}, \\{ \\{ \\text{Bob} \\}, \\{ \\text{FileA} \\}, \\{ \\text{write} \\} \\} > \\]\n\n3.3.1.4 Rule (R) Definition and Syntax\n\nA rule \\( R \\) is the most elementary element of a policy. A rule contains rule conditions, target and rule effect. It is mapped to SBA-XACML according to the following syntax:\n\n\\[ R ::= < ID, RC, TR, RE > \\] \n\n(Construct 6)\n\nwhere \\( ID \\) is the rule id, \\( RC \\) is the set of rule conditions, \\( TR \\) is the target (refer to Section 3.3.1.1 section for details), and \\( RE \\) is the rule effect.\n\nA rule condition \\( RC \\) is a boolean function over subjects, resources, actions or functions of attributes. It is mapped to SBA-XACML within the context of a rule according to the following syntax:\n\\[ RC = \\{ \\text{Applyfunction}, \\{ \\text{parameters} \\} \\} \\]\n\n(Construct 7)\n\nwhere \\text{Applyfunction} is the function used in evaluating the elements in the apply and \\text{parameters} are the input to the function being applied, each of which is an evaluatble.\n\nExample 3: Consider a rule \\( R_1 \\) with \\text{ruleeffect} = \\text{permit}. \\( R_1 \\) has no target defined. Its only condition is that anyone accessing \\text{File} 1 is allowed at any time. The rule is mapped to SBA-XACML as follows:\n\n\\[\nR ::=< R_1, \\{ \\text{string} - \\text{equal}, \\{ \\text{ResourceAttributeDesignator}, \\text{string}, \\text{File} 1 \\} \\}, \\{ \\}, \\{ \\}, \\{ \\} \\}, \\{ \\text{Permit} \\} >\n\\]\n\n3.3.2 SBA-XACML Request\n\nA request \\( Rq \\) is a call for access to some resources. It is mapped to SBA-XACML according to the following syntax:\n\n\\[\nRq ::= < S_r, R_r, A_r >\n\\]\n\n(Construct 8)\n\nwhere \\( S_r \\) is the set of subjects, \\( R_r \\) is the set of resources and \\( A_r \\) is the set of actions.\n\nExample 4: Consider a request calling for access with subject \\text{Bob}, resource \\text{ServerA} and action \\text{read}. The request is mapped to SBA-XACML as follows:\n\n\\[\nRq ::= < \\{ \\text{Bob} \\}, \\{ \\text{ServerA} \\}, \\{ \\text{Read} \\} >\n\\]\n3.3.3 SBA-XACML Response\n\nA response $Rs$ is a decision to a request against a based policy. It is mapped to SBA-XACML according to the following syntax:\n\n$$Rs ::= < D, OBLs >$$\n\n(Construct 9)\n\nwhere $D$ is the decision of the response and $OBLs$ is the set of obligations to be executed within the response (refer to Section 3.3.1.1 section for details).\n\nExample 5: The response to the request in Example 4 is mapped to SBA-XACML as follows:\n\n$$Rs ::= < \\{permit\\}, {} >$$\n\n3.4 Policy Evaluation Semantics\n\nIn this section, we present the formal semantics of a SBA-XACML policy evaluation following the above inference rule structure and deductive logic. Given a policy set $PS$ and a request $Rq$, the response $Rs$ is derived by the evaluation $\\rightarrow_{eval}$ of all premises combined between each other using designated operators $op$ as follows:\n\n$$\\begin{align*}\n(premise_1) & \\quad op \\quad (premise_2) \\quad op \\quad ... \\quad op \\quad (premise_n) \\\\\n\\hline\n< PS, Rq > & \\quad \\rightarrow_{eval} \\quad Rs\n\\end{align*}$$\n\nThe policy and rule evaluation semantics rules, which constitute the premises in the above rule, have also similar structure and follows the deductive logic until reaching the basic defined premise (i.e. condition). Throughout the rest of the thesis, please note the\ndifference between a semantic rule that express the evaluation at a particular level, and a policy rule which is a construct in SBA-XACML. All the semantics rules follow the bottom up structure, where all the common ones are presented first, then followed by the rule level, policy level and policy set level ones. In this context, we start first by defining the MatchFunction semantics rule since it will be used throughout all levels.\n\n### 3.4.1 Match Function\n\nIn this section, we present the matching semantics rules for a request \\( Rq \\) with subject set \\( Sr \\), resource set \\( Rr \\) and action set \\( Ar \\) against a target \\( TR \\) with subject set \\( S \\), resource set \\( R \\) and action set \\( A \\). The semantics of matching a request and a target is determined by comparing the request subject set \\( Sr \\) with target subject set \\( S \\), request resource set \\( Rr \\) with target resource set \\( R \\) and request action set \\( Ar \\) with target action set \\( A \\).\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Match Function Semantics Rules</th>\n</tr>\n</thead>\n</table>\n| Rule 1 | \\(((Sr \\cap S) \\neq \\emptyset) \\land ((Rr \\cap R) \\neq \\emptyset) \\land ((Ar \\cap A) \\neq \\emptyset)\\) \n \\[ < TR, Rq > \\vdash_{\\text{match}} True \\] |\n| Rule 2 | \\(((Sr \\cap S) = \\emptyset) \\lor ((Rr \\cap R) = \\emptyset) \\lor ((Ar \\cap A) = \\emptyset)\\) \n \\[ < TR, Rq > \\vdash_{\\text{match}} False \\] |\n\nRules 1 and 2 in Table 1 describe the different matching cases for a request \\( Rq \\) with a target \\( TR \\). In Rule 1 a target \\( TR \\) matches a request \\( Rq \\) if the requested subject set \\( Sr \\) intersects with the target subject set \\( S \\), the requested resource set \\( Rr \\) intersects with the target resource set \\( R \\) and the requested action set \\( Ar \\) intersects with the target action set \\( A \\).\nIn Rule 2 a target TR does not match a request Rq if the requested subject set Sr does not intersects with the target subject set S, the requested resource set Rr does not intersect with the target resource set R or the requested action set Ar does not intersect with the target action set A.\n\n### 3.4.2 Rule Evaluation\n\nIn this section, we present the evaluation semantics rules for a request Rq at the rule level.\n\nSemantics Rules 3, 4 and 5 in Table 2 describe the different evaluation cases for a policy rule R. In semantics Rule 3, a policy rule R evaluates a request Rq to Permit if the target matches with the request elements (see details in semantics Rule 1) and rule conditions RC evaluate to True and rule effect RE is Permit. In semantics Rule 4, a policy rule R evaluates a request Rq to Deny if the target matches with the request elements (see details in semantics Rule 1) and rule conditions RC evaluate to True and rule effect RE is Deny.\nIn semantics Rule 5, a policy rule $R$ evaluates a request $Rq$ to $NotApplicable$ if either the target does not match with the request elements (see details in semantics Rule 2) or rule conditions $RC$ evaluate to $False$.\n\n### 3.4.3 Policy Evaluation\n\nIn this section, we present the evaluation semantics rules for a request $Rq$ at the policy level.\n\nTable 3: Evaluation Semantics Rules of a Policy (RCA=Permit-Overrides)\n\n<table>\n<thead>\n<tr>\n<th>Rule Number</th>\n<th>Rule Description</th>\n</tr>\n</thead>\n</table>\n| 6 | $\\text{(RCA = Permit − Overrides)} \\land$ \\[\n\\begin{align*}\n&(< TR, Rq > \\vdash \\text{match True}) \\land (\\exists R \\in SR; < R, Rq > \\xrightarrow{\\text{eval}} \\text{Permit}) \\\\\n&\\quad \\implies < P, Rq > \\xrightarrow{\\text{eval}} \\text{Permit}, OBLs\n\\end{align*}\n\\] |\n| 7 | $\\text{(RCA = Permit − Overrides)} \\land$ \\[\n\\begin{align*}\n&(< TR, Rq > \\vdash \\text{match True}) \\land (\\forall R \\in SR; < R, Rq > \\xrightarrow{\\text{eval}} \\text{Deny}) \\\\\n&\\quad \\implies < P, Rq > \\xrightarrow{\\text{eval}} \\text{Deny}, OBLs\n\\end{align*}\n\\] |\n| 8 | $\\text{(RCA = Permit − Overrides)} \\land$ \\[\n\\begin{align*}\n&((< TR, Rq > \\vdash \\text{match False}) \\lor (\\forall R \\in SR; < R, Rq > \\xrightarrow{\\text{eval}} \\text{NotApplicable})) \\\\\n&\\quad \\implies < P, Rq > \\xrightarrow{\\text{eval}} \\text{NotApplicable}\n\\end{align*}\n\\] |\n\nRules 6, 7 and 8 in Table 3 describe the cases where the rule combining algorithm (RCA) is $\\text{Permit − Overrides}$. In Rule 6, a policy $P$ evaluates a request $Rq$ to $\\text{Permit}$ with a list of obligations $OBLs$ if the target matches with the request elements (see details in semantics Rule 1) and there exists a rule $R$ in the set of Rules $SR$ that evaluates to $\\text{Permit}$ (see details in semantics Rule 3). In Rule 7, a policy $P$ evaluates a request $Rq$ to $\\text{Deny}$ with a list of obligations $OBLs$ if the target matches with the request elements (see details in\nsemantics Rule 1) and all rules in the set of Rules SR that evaluates to Deny (see details in semantics Rule 4). In Rule 8, a policy $P$ evaluates a request $R_q$ to NotApplicable if either the target does not match with the request elements (see details in semantics Rule 2) or all rules in the set of Rules SR that evaluates to NotApplicable (see details in semantics Rule 5).\n\nRules 9, 10, 11 in Table 4 describe the cases where the rule combining algorithm (RCA) is Deny – Overrides. In Rule 9, a policy $P$ evaluates a request $R_q$ to Deny with a list of obligations $OBLs$ if the target matches with the request elements (see details in semantics Rule 1) and there exists a rule $R$ in the set of Rules SR that evaluates to Deny (see details in semantics Rule 4). In rule 10, a policy $P$ evaluates a request $R_q$ to Deny with a list of obligations $OBLs$ if the target matches with the request elements (see details in semantics Rule 1) and all rules in the set of Rules SR that evaluates to Permit (see details in semantics\n\n<table>\n<thead>\n<tr>\n<th>Table 4: Evaluation Semantics Rules of a Policy (RCA=Deny-Overrides)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>$(RCA = \\text{Deny} - \\text{Overrides}) \\land$</td>\n</tr>\n<tr>\n<td>$(< TR, R_q > \\vdash_{\\text{match}} \\text{True}) \\land (\\exists R \\in SR; < R, R_q > \\xrightarrow{\\text{eval}} \\text{Deny})$</td>\n</tr>\n<tr>\n<td>$< P, R_q > \\xrightarrow{\\text{eval}} \\text{Deny}, OBLs$</td>\n</tr>\n<tr>\n<td>(Rule 9)</td>\n</tr>\n<tr>\n<td>$(RCA = \\text{Deny} - \\text{Overrides}) \\land$</td>\n</tr>\n<tr>\n<td>$(< TR, R_q > \\vdash_{\\text{match}} \\text{True}) \\land (\\forall R \\in SR; < R, R_q > \\xrightarrow{\\text{eval}} \\text{Permit})$</td>\n</tr>\n<tr>\n<td>$< P, R_q > \\xrightarrow{\\text{eval}} \\text{Permit}, OBLs$</td>\n</tr>\n<tr>\n<td>(Rule 10)</td>\n</tr>\n<tr>\n<td>$(RCA = \\text{Deny} - \\text{Overrides}) \\land$</td>\n</tr>\n<tr>\n<td>$((< TR, R_q > \\vdash_{\\text{match}} \\text{False}) \\lor (\\forall R \\in SR; < R, R_q > \\xrightarrow{\\text{eval}} \\text{NotApplicable}))$</td>\n</tr>\n<tr>\n<td>$< P, R_q > \\xrightarrow{\\text{eval}} \\text{NotApplicable}$</td>\n</tr>\n<tr>\n<td>(Rule 11)</td>\n</tr>\n</tbody>\n</table>\nRule 3). In rule 11, a policy \\( P \\) evaluates a request \\( Rq \\) to \\textit{NotApplicable} if either the target does not match with the request elements (see details in semantics Rule 2) or all rules in the set of Rules \\( SR \\) that evaluates to \\textit{NotApplicable} (see details in semantics Rule 5).\n\nTable 5: Evaluation Semantics Rules of a Policy (RCA=First-Applicable)\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Semantics</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>(RCA = \\textit{First - Applicable}) \\land \\langle TR, Rq \\rangle \\dashv \\text{match} \\land (\\exists R1, R2 \\in SR: ((PR = R1 > R2) \\land (< R1, Rq > eval \\text{Permit})) \\land \\langle P, Rq \\rangle eval \\text{Permit}, OBLs)</td>\n<td>(Rule 12)</td>\n</tr>\n<tr>\n<td>(RCA = \\textit{First - Applicable}) \\land \\langle TR, Rq \\rangle \\dashv \\text{match} \\land (\\exists R1, R2 \\in SR: ((PR = R1 > R2) \\land (< R1, Rq > eval \\text{Deny})) \\land \\langle P, Rq \\rangle eval \\text{Deny}, OBLs)</td>\n<td>(Rule 13)</td>\n</tr>\n<tr>\n<td>(RCA = \\textit{First - Applicable}) \\land ((< TR, Rq > \\dashv \\text{match} False) \\lor (\\forall R \\in SR; < R, Rq > eval \\text{NotApplicable}) \\land \\langle P, Rq \\rangle eval \\text{NotApplicable})</td>\n<td>(Rule 14)</td>\n</tr>\n</tbody>\n</table>\n\nRules 12, 13 and 14 in Table 5 describe the cases where the rule combining algorithm (RCA) is \\textit{First - Applicable}. In Rule 12, a policy \\( P \\) evaluates a request \\( Rq \\) to \\textit{Permit} with a list of obligations \\textit{OBLs} if the target matches with the request elements (see details in semantics Rule 1) and there exists two rules \\( R1 \\) and \\( R2 \\) in the set of rules \\( SR \\) such that the precedence \\( PR = R1 > R2 \\) and \\( R1 \\) evaluates to \\textit{Permit} (see details in semantics Rule 3). In Rule 13, a policy \\( P \\) evaluates a request \\( Rq \\) to \\textit{Deny} with a list of obligations \\textit{OBLs} if the target matches with the request elements (see details in semantics Rule 1) and\nthere exists two rules $R_1$ and $R_2$ in the set of rules $SR$ such that the precedence $PR = R_1 > R_2$ and $R_1$ evaluates to $Deny$ (see details in semantics Rule 4). In Rule 13, a policy $P$ evaluates a request $Rq$ to $NotApplicable$ if either the target does not match with the request elements (see details in semantics Rule 2) or all rules in the set of Rules $SR$ that evaluates to $NotApplicable$ (see details in semantics Rule 5).\n\n### 3.4.4 PolicySet Evaluation\n\nIn this section, we present the evaluation rules for a request $Rq$ at the policy set level.\n\n**Table 6: Evaluation Semantics Rules of a PolicySet (PCA=Permit-Overrides)**\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>15</td>\n<td>$(PCA = Permit − Overrides) \\land (\\langle TR, Rq \\rangle \\vdash \\text{match} \\ True) \\land (\\exists P \\in SP; \\langle P, Rq \\rangle \\xrightarrow{eval} \\text{Permit}) \\quad \\text{(Rule 15)}$</td>\n</tr>\n<tr>\n<td></td>\n<td>$\\langle PS, Rq \\rangle \\xrightarrow{eval} \\text{Permit, OBLs}$</td>\n</tr>\n<tr>\n<td>16</td>\n<td>$(PCA = Permit − Overrides) \\land (\\langle TR, Rq \\rangle \\vdash \\text{match} \\ True) \\land (\\forall P \\in SP; \\langle P, Rq \\rangle \\xrightarrow{eval} \\text{Deny}) \\quad \\text{(Rule 16)}$</td>\n</tr>\n<tr>\n<td></td>\n<td>$\\langle PS, Rq \\rangle \\xrightarrow{eval} \\text{Deny, OBLs}$</td>\n</tr>\n<tr>\n<td>17</td>\n<td>$(PCA = Permit − Overrides) \\land (\\langle TR, Rq \\rangle \\vdash \\text{match} \\ False) \\lor (\\forall P \\in SP; \\langle P, Rq \\rangle \\xrightarrow{eval} \\text{NotApplicable}) \\quad \\text{(Rule 17)}$</td>\n</tr>\n<tr>\n<td></td>\n<td>$\\langle PS, Rq \\rangle \\xrightarrow{eval} \\text{NotApplicable}$</td>\n</tr>\n</tbody>\n</table>\n\nRules 15, 16 and 17 in Table 6 describe the cases where the policy combining algorithm $(PCA)$ is $Permit − Overrides$. In Rule 15, a policy set $PS$ evaluates a request $Rq$ to $Permit$ with a list of obligations $OBLs$ if the target matches with the request elements (see details in semantics Rule 1) and there exists a policy $P$ in the set of policies $SP$ that\nevaluates to Permit (see details in semantics Rules 6, 10, 12). In Rule 16, a policy set $PS$ evaluates a request $Rq$ to Deny with a list of obligations $OBLs$ if the target matches with the request elements (see details in semantics Rule 1) and all policies in the set of policies $SP$ that evaluates to Deny (see details in semantics Rules 7, 9, 13). In Rule 17, a policy set $PS$ evaluates a request $Rq$ to NotApplicable if either the target does not match with the request elements (see details in semantics Rule 2) or all policies in the set of policies $SP$ that evaluates to NotApplicable (see details in semantics Rules 8, 11, 14).\n\nTable 7: Evaluation Semantics Rules of a PolicySet (PCA=Deny-Overrides)\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Rule 18</td>\n<td>$(PCA = \\text{Deny} - \\text{Overrides}) \\land (\\text{match}_\\text{True} \\land (\\exists P \\in SP; < P, Rq > \\overset{\\text{eval}}{\\longrightarrow} \\text{Deny})) \\implies < PS, Rq > \\overset{\\text{eval}}{\\longrightarrow} \\text{Deny}, OBLs$</td>\n</tr>\n<tr>\n<td>Rule 19</td>\n<td>$(PCA = \\text{Deny} - \\text{Overrides}) \\land (\\text{match}_\\text{True} \\land (\\forall P \\in SP; < P, Rq > \\overset{\\text{eval}}{\\longrightarrow} \\text{Permit}) \\implies < PS, Rq > \\overset{\\text{eval}}{\\longrightarrow} \\text{Permit}, OBLs$</td>\n</tr>\n<tr>\n<td>Rule 20</td>\n<td>$(PCA = \\text{Deny} - \\text{Overrides}) \\land ((\\text{match}_\\text{False} \\lor (\\forall P \\in SP; < P, Rq > \\overset{\\text{eval}}{\\longrightarrow} \\text{NotApplicable})) \\implies < PS, Rq > \\overset{\\text{eval}}{\\longrightarrow} \\text{NotApplicable}$</td>\n</tr>\n</tbody>\n</table>\n\nRules 18, 19 and 20 in Table 7 describe the cases where the policy combining algorithm (PCA) is Deny – Overrides. In Rule 18, a policy set $PS$ evaluates a request $Rq$ to Deny with a list of obligations $OBLs$ if the target matches with the request elements (see details in semantics Rule 1) and there exists a policy $P$ in the set of policies $SP$ that evaluates to Deny (see details in semantics Rules 7, 9, 13). In Rule 19, a policy set $PS$ evaluates a request $Rq$...\nto *Permit* with a list of obligations *OBLs* if the target matches with the request elements (see details in semantics Rule 1) and all policies in the set of policies *SP* that evaluates to *Permit* (see details in semantics Rules 6, 10, 12). In Rule 20, a policy set *PS* evaluates a request *Rq* to *NotApplicable* if either the target does not match with the request elements (see details in semantics Rule 2) or all policies in the set of policies *SP* that evaluates to *NotApplicable* (see details in semantics Rules 8, 11, 14).\n\nTable 8: Evaluation Semantics Rules of a PolicySet (PCA=First-Applicable)\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>21.1</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\\[\n(PCA = First - Applicable) \\land \\\\\n(< TR, Rq > \\vdash True) \\land \\\\\n(\\exists P_1, P_2 \\in SP; ((PR = P_1 > P_2) \\land (< P_1, Rq > \\rightarrow_{eval} Permit)))\n\\]\n\n< PS, Rq > \\rightarrow_{eval} Permit, OBLs |\n\n| 22.1 | \n\\[\n(PCA = First - Applicable) \\land \\\\\n(< TR, Rq > \\vdash True) \\land \\\\\n(\\exists P_1, P_2 \\in SP; ((PR = P_1 > P_2) \\land (< P_1, Rq > \\rightarrow_{eval} Deny)))\n\\]\n\n< PS, Rq > \\rightarrow_{eval} Deny, OBLs |\n\n| 23.1 | \n\\[\n(PCA = First - Applicable) \\land \\\\\n((< TR, Rq > \\vdash False) \\lor (\\forall P \\in SP; < P, Rq > \\rightarrow_{eval} NotApplicable))\n\\]\n\n< PS, Rq > \\rightarrow_{eval} NotApplicable |\n\nRules 21, 22 and 23 in Table 8 describe the cases where the policy combining algorithm *(PCA)* is *First – Applicable*. In Rule 21, a policy set *PS* evaluates a request *Rq* to *Permit* with a list of obligations *OBLs* if the target matches with the request elements (see details in semantics Rule 1) and there exists a policy *P1* and *P2* in the set of policies *SP* such that\nthe precedence order $PR = P1 > P2$ and $P1$ evaluates to $Permit$ (see details in semantics Rules 6, 10, 12). In Rule 22, a policy set $PS$ evaluates a request $Rq$ to $Permit$ with a list of obligations $OBLs$ if the target matches with the request elements (see details in semantics Rule 1) and all policies in the set of policies $SP$ that evaluates to $Deny$ (see details in semantics Rules 7, 9, 13). In Rule 23, a policy set $PS$ evaluates a request $Rq$ to $NotApplicable$ if either the target does not match with the request elements (see details in semantics Rule 2) or all policies in the set of policies $SP$ that evaluates to $NotApplicable$ (see details in semantics Rules 8, 11, 14).\n\nTable 9: Evaluation Semantics Rules of a PolicySet (PCA=Only-one-Applicable)\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Evaluation Rule</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Rule 24</td>\n<td>$(PCA = Only - one - Applicable) \\land \\leftarrow< TR, Rq > \\vdash match True \\land (\\exists P \\in SP; < P, Rq > \\rightarrow eval Permit) \\rightarrow eval PS, Rq \\rightarrow eval Permit, OBLs$</td>\n</tr>\n<tr>\n<td>Rule 25</td>\n<td>$(PCA = Only - one - Applicable) \\land \\leftarrow< TR, Rq > \\vdash match True \\land (\\exists P \\in SP; < P, Rq > \\rightarrow eval Deny) \\rightarrow eval PS, Rq \\rightarrow eval Deny, OBLs$</td>\n</tr>\n<tr>\n<td>Rule 26</td>\n<td>$(PCA = Only - one - Applicable) \\land \\leftarrow< TR, Rq > \\vdash match False \\lor (\\forall P \\in SP; < P, Rq > \\rightarrow eval NotApplicable) \\rightarrow eval PS, Rq \\rightarrow eval NotApplicable$</td>\n</tr>\n<tr>\n<td>Rule 27</td>\n<td>$(PCA = Only - one - Applicable) \\land \\leftarrow< TR, Rq > \\vdash match True \\land (\\exists P1, P2 \\in SP; (< P1, Rq > \\rightarrow eval Deny \\lor Permit) \\land (< P2, Rq > \\rightarrow eval Deny \\lor Permit)) \\rightarrow eval PS, Rq \\rightarrow eval Indeterminate$</td>\n</tr>\n</tbody>\n</table>\nRules 24, 25, 26 and 27 in Table 9 describe the cases where the policy combining algorithm (PCA) is \\textit{Only \\textendash one \\textendash Applicable}. In Rule 24, a policy set \\( PS \\) evaluates a request \\( Rq \\) to \\textit{Permit} with a list of obligations \\( OBLs \\) if the target matches with the request elements (see details in semantics Rule 1) and there exists one and only policy \\( P \\) in the set of policies \\( SP \\) that evaluates to \\textit{Permit} (see details in semantics Rules 6, 10, 12). In Rule 25, a policy set \\( PS \\) evaluates a request \\( Rq \\) to \\textit{Deny} with a list of obligations \\( OBLs \\) if the target matches with the request elements (see details in semantics Rule 1) and there exists one and only policy \\( P \\) in the set of policies \\( SP \\) that evaluates to \\textit{Deny} (see details in semantics Rules 7, 9, 13). In Rule 26, a policy set \\( PS \\) evaluates a request \\( Rq \\) to \\textit{NotApplicable} if either the target does not match with the request elements (see details in semantics Rule 2) or all policies in the set of policies \\( SP \\) that evaluates to \\textit{NotApplicable} (see details in semantics Rules 8, 11, 14). In Rule 27, a policy set \\( PS \\) evaluates a request \\( Rq \\) to \\textit{Indeterminate} if the target matches with the request elements (see details in semantics Rule 1) and there exists at least two policies \\( P1 \\) and \\( P2 \\) in the set policies \\( SP \\) such that \\( P1 \\) evaluates to either \\textit{Permit} or \\textit{Deny} and \\( P2 \\) evaluates to either \\textit{Permit} or \\textit{Deny}.\n\n3.5 Policy Evaluation Algorithms\n\nIn this section, we present the algorithms realizing the SBA-XACML policy evaluation semantics. We divided the evaluation module into three algorithms. Each one of them evaluates the request at a separate layer in the based policy. The rule evaluation algorithm is presented in Algorithm 1, the policy evaluation algorithm in Algorithm 2 and the policy set evaluation algorithm in Algorithm 3.\n3.5.1 Rule Evaluation Algorithm\n\nThe rule evaluation algorithm in Algorithm 1 evaluates the request at the lowest level in the policy set. It takes two inputs: a rule \\( R \\) and a request \\( R_q \\). The output is the rule decision which is \\( \\text{Deny} \\), \\( \\text{Permit} \\), or \\( \\text{NotApplicable} \\).\n\n**Algorithm 1 Rule_Evaluation(\\( \\hat{R}, R_q \\))**\n\n**Input**: 1) A Rule \\( R \\) with Target \\( TR = \\{S,R,A\\} \\) and (2) A Request \\( R_q = \\{Sr,Rr,Ar\\} \\)\n\n**Output**: Rule decision \\( \\in \\{\\text{RE}, \\text{NotApplicable}\\} \\) where \\( \\text{RE} \\in \\{\\text{Permit, Deny}\\} \\)\n\n1: // Rule Applicability Check\n2: \\text{if} \\ ((Sr \\cap S) \\neq \\emptyset) \\land ((Rr \\cap R) \\neq \\emptyset) \\land ((Ar \\cap A) \\neq \\emptyset) \\text{ then}\n3: // loop through Rule Conditions\n4: \\text{for} \\ i := 1 \\text{ to } m \\text{ do}\n5: //At least one Rule Condition evaluated to false\n6: \\text{if} \\ \\exists \\ i, 0 < i \\leq m, RC = \"false\" \\text{ then}\n7: \\text{return} \\ NotApplicable;\n8: \\text{else}\n9: //All Rule Conditions evaluated to true\n10: \\text{return} \\ RE;\n11: \\text{end if}\n12: \\text{end for}\n13: \\text{else}\n14: //Rule NotApplicable to the request\n15: \\text{return} \\ NotApplicable;\n16: \\text{end if}\n\nThe Rule Evaluation in Algorithm 1 takes two inputs: a rule \\( R \\) and a request \\( R_q \\). It begins by checking whether the rule is applicable to the request (line 2). The Applicability check is done by comparing the request set of subjects, set of resources and set of actions against the rule target. If the applicability check returns true then the rule conditions are evaluated (line 6), otherwise \"NotApplicable\" is returned to the Policy Evaluation in Algorithm 2 (line 15). Rule effect is returned if all rule conditions evaluate to true (line 10) otherwise \"NotApplicable\" is returned to the Policy Evaluation in Algorithm 2 (line 7).\n3.5.2 Policy Evaluation Algorithm\n\nThe policy evaluation algorithm in Algorithm 2 evaluates the request at the middle layer. It calls the rule evaluation Algorithm 1 to handle the evaluation at the lower layer. It takes two inputs: a policy \\( P \\) and a request \\( Rq \\). The output is the policy decision which is \\( Deny \\), \\( Permit \\), or \\( NotApplicable \\).\n\nThe policy evaluation algorithm in Algorithm 2 takes two inputs: a policy \\( P \\) and a request \\( Rq \\). The algorithm is composed of three steps: the applicability check of the policy, the evaluation of rules and rule combining algorithm \\( RCA \\). The applicability check is done by matching the request subjects, resources and actions with policy target (line 1). If (line 1) returns true, we call step 2, otherwise \\( NotApplicable \\) is returned to the policy set evaluation in Algorithm 3. The evaluation of rules is done by the order they are listed in the policy. The rule evaluation algorithm Algorithm 1 is called in line 3. The response returned is passed to step 3, where \\( RCA \\) can have one of the following values: \\( Permit - Overrides \\), \\( Deny - Overrides \\) or \\( First - Applicable \\). If the \\( RCA \\) is \\( Permit - Overrides \\) and step 2 returns one \\( Permit \\), then the returned response is \\( Permit \\). If \\( RCA \\) is \\( Permit - Overrides \\) and step 2 returns \\( Deny \\) for all rules, then the returned response is \\( Deny \\). If \\( RCA \\) is \\( Permit - Overrides \\) and step 2 returns \\( NotApplicable \\) for all rules, then the returned response is \\( NotApplicable \\). If \\( RCA \\) is \\( Deny - Overrides \\) and step 2 returns one \\( Deny \\) then the returned response is \\( Deny \\). If \\( RCA \\) is \\( Deny - Overrides \\) and step 2 returns \\( Permit \\) for all rules, then the returned response is \\( Permit \\). If \\( RCA \\) is \\( Deny - Overrides \\) and step 2 returns \\( NotApplicable \\) for all rules, then the returned response is \\( NotApplicable \\). If \\( RCA \\) is \\( First - Applicable \\) and step 2 returns one \\( Deny \\) or \\( Permit \\), then the returned\nAlgorithm 2 Policy_Evaluation\\((P, Rq)\\)\n\n**Input**: 1) A Policy \\(P\\) with Target \\(TR = \\{S, R, A\\}\\) and (2) A Request \\(Rq = \\{Sr, Rr, Ar\\}\\)\n\n**Output**: Policy decision \\(\\in\\{\\text{Deny, Permit, NotApplicable}\\}\\)\n\n1: \\textbf{if} \\((S \\cap S) \\neq \\emptyset) \\land ((R \\cap R) \\neq \\emptyset) \\land ((A \\cap A) \\neq \\emptyset)\\) then\n2: \\hspace{1em} \\textbf{for} \\(i := 1\\) to \\(m\\) do\n3: \\hspace{2em} // Call Rule Evaluation Algorithm\n4: \\hspace{3em} RE\\(_i\\) =\n5: \\hspace{4em} \\textbf{if} (RCA = \"Deny-Overrides\") then\n6: \\hspace{5em} // if at least one rule evaluates to Deny\n7: \\hspace{6em} if \\(\\exists i, 0 < i \\leq m, RE_i = \"Deny\"\\) then\n8: \\hspace{7em} \\textbf{return} Deny;\n9: \\hspace{5em} \\textbf{else}\\n10: \\hspace{6em} // If all rules evaluate to permit\n11: \\hspace{7em} if \\(\\forall i, 0 < i \\leq m, RE_i = \"Permit\"\\) then\n12: \\hspace{8em} \\textbf{return} Permit;\n13: \\hspace{6em} \\textbf{else}\n14: \\hspace{7em} \\textbf{return} NotApplicable;\n15: \\hspace{5em} \\textbf{end if}\n16: \\hspace{4em} \\textbf{end if}\n17: \\hspace{3em} \\textbf{end if}\n18: \\hspace{2em} \\textbf{if} (RCA = \"Permit-Overrides\") then\n19: \\hspace{3em} // At least one rule evaluates to Permit\n20: \\hspace{4em} if \\(\\exists i, 0 < i \\leq m, RE_i = \"Permit\"\\) then\n21: \\hspace{5em} \\textbf{return} Permit;\n22: \\hspace{3em} \\textbf{else}\\n23: \\hspace{4em} // All deny\n24: \\hspace{5em} if \\(\\forall i, 0 < i \\leq m, RE_i = \"Deny\"\\) then\n25: \\hspace{6em} \\textbf{return} Deny;\n26: \\hspace{5em} \\textbf{else}\n27: \\hspace{6em} \\textbf{return} NotApplicable;\n28: \\hspace{4em} \\textbf{end if}\n29: \\hspace{3em} \\textbf{end if}\n30: \\hspace{2em} \\textbf{if} (RCA = \"First-Applicable\") then\n31: \\hspace{3em} //First Applicable rule evaluates to permit\n32: \\hspace{4em} if \\(\\exists i, 0 < i \\leq m, RE_i = \"Permit\"\\) then\n33: \\hspace{5em} \\textbf{return} Permit;\n34: \\hspace{3em} \\textbf{else}\\n35: \\hspace{4em} //First Applicable rule evaluates to deny\n36: \\hspace{5em} if \\(\\exists i, 0 < i \\leq m, RE_i = \"Deny\"\\) then\n37: \\hspace{6em} \\textbf{return} Deny;\n38: \\hspace{5em} \\textbf{else}\n39: \\hspace{6em} \\textbf{return} NotApplicable;\n40: \\hspace{4em} \\textbf{end if}\n41: \\hspace{3em} \\textbf{end if}\n42: \\hspace{2em} \\textbf{end if}\n43: \\hspace{1em} \\textbf{end for}\n44: \\hspace{1em} \\textbf{else}\n45: \\hspace{2em} //Policy is not Applicable by target\n46: \\hspace{3em} \\textbf{return} NotApplicable;\n47: \\hspace{1em} \\textbf{end if}\nresponse is *Deny* or *Permit* respectively. If RCA is *First—Applicable* and step 2 returns *NotApplicable* for all rules, then the returned response is *NotApplicable*.\n\n### 3.5.3 PolicySet Evaluation Algorithm\n\nThe policy set evaluation algorithm in Algorithm 3 calls the policy evaluation algorithm Algorithm 2 to handle the evaluation at the middle layer. The algorithm takes two inputs: a policy set $PS$ and a request $Rq$. The output is the final response to the request $Rs$.\n\nThe PolicySet Evaluation in Algorithm 3 takes two inputs: a policy set $PS$ and a request $Rq$. The algorithm is composed of three steps: the applicability check of the policy set, the evaluation of policies and policy combining algorithm $PCA$. The applicability check is done by evaluating the request subjects, resources and actions with the policy set target in line 2. If it returns true, then step 2 is called otherwise $Rs = NotApplicable$ is returned as the request response. The evaluation of policies is done by the order they are listed in the based policy. The policy evaluation algorithm Algorithm 2 is called in line 6. The returned response is passed to step 3, where the $PCA$ can have one of the following values: *Permit—Overrides, Deny—Overrides, First—Applicable* or *Only—one—Applicable*. If the $PCA$ is *Permit — Overrides* and step 2 returns one *Permit*, then the returned response is *Permit*. If the $PCA$ is *Permit — Overrides* and step 2 returns *Deny* for all policies, then the returned response is *Deny*. If the $PCA$ is *Permit — Overrides* and step 2 returns *NotApplicable* for all policies, then the returned response is *NotApplicable*. If the $PCA$ is *Deny — Overrides* and step 2 returns one *Deny*, then the returned response is *Deny*. If the $PCA$ is *Deny — Overrides* and step 2 returns *Permit* for all policies,\nAlgorithm 3 PolicySet_Evaluation(PS, Rq) Part 1\n\n**Input**: (1) A PolicySet PS with Target TR = {S,R,A} and (2) Request Rq = {Sr,Rr,Ar}\n\n**Output**: Request response Rs ∈ {Permit, Deny, NotApplicable, Indeterminate}\n\n1: // PolicySet Applicability Check\n2: if \\((Sr \\cap S) \\neq \\emptyset \\land (Rr \\cap R) \\neq \\emptyset \\land (Ar \\cap A) \\neq \\emptyset\\) then\n3: // loop through Policies\n4: for \\(i := 1 \\text{ to } m\\) do\n5: // Call Policy Evaluation function\n6: PEi = POLICY_EVALUATION(Pi, Rq);\n7: if (PCA = \"Deny-Overrides\") then\n8: // if at least one policy evaluates to Deny\n9: if \\(\\exists i, 0 < i \\leq m, \\text{PEi} = \\text{\"Deny\"}\\) then\n10: return Deny;\n11: else\n12: // If all policies evaluate to Permit\n13: if \\(\\forall i, 0 < i \\leq m, \\text{PEi} = \\text{\"Permit\"}\\) then\n14: return Permit;\n15: else\n16: return NotApplicable;\n17: end if\n18: end if\n19: end if\n20: if (PCA = \"Permit-Overrides\") then\n21: // if at least one policy evaluates to Permit\n22: if \\(\\exists i, 0 < i \\leq m, \\text{PEi} = \\text{\"Permit\"}\\) then\n23: return Permit;\n24: else\n25: // If all policies evaluate to Deny\n26: if \\(\\forall i, 0 < i \\leq m, \\text{PEi} = \\text{\"Deny\"}\\) then\n27: return Deny;\n28: else\n29: return NotApplicable;\n30: end if\n31: end if\n32: if (PCA = \"First-Applicable\") then\n33: // if at least one policy evaluates to Deny\n34: if \\(\\exists i, 0 < i \\leq m, \\text{PEi} = \\text{\"Deny\"}\\) then\n35: return Deny;\n36: else\n37: // if at least one Policy evaluates to Permit\n38: if \\(\\exists i, 0 < i \\leq m, \\text{PEi} = \\text{\"Permit\"}\\) then\n39: return Permit;\n40: else\n41: return NotApplicable;\n42: end if\n43: end if\n44: end if\nAlgorithm 3 PolicySet_Evaluation(PS, Rq) Part 2\n\n46: //PCA = Only-one-Applicable\n47: if (PCA = \"Only-one-Applicable\") then\n48: // iff one policy evaluates to Deny\n49: if \\( \\exists \\ i, 0 < i \\leq m, \\text{PEi} = \"Deny\" \\) then\n50: return Deny;\n51: end if\n52: // Iff one Policy evaluates to permit\n53: if \\( \\exists \\ i, 0 < i \\leq m, \\text{PEi} = \"Permit\" \\) then\n54: return Permit;\n55: end if\n56: // If all policies evaluate to NotApplicable\n57: if \\( \\forall \\ i, 0 < i \\leq m, \\text{PEi} = \"NotApplicable\" \\) then\n58: return NotApplicable;\n59: else\n60: // More than one applicable policies\n61: return Indeterminate;\n62: end if\n63: end if\n64: end for\n65: else\n66: // PolicySet NotApplicable to the request\n67: return NotApplicable;\n68: end if\n\nthen the returned response is Permit. If the PCA is Deny – Overrides and step 2 returns NotApplicable for all policies, then the returned response is NotApplicable. If the PCA is First – Applicable and step 2 returns one Deny or Permit, then the returned response is Deny or Permit respectively. If the PCA is First – Applicable and step 2 returns NotApplicable for all policies, then the returned response is NotApplicable. If the PCA is Only – One – Applicable and only one policy is applicable, the response is either Deny or Permit, otherwise the response is Indeterminate.\n3.6 Case Study: SBA-XACML Policy Evaluation and Performance Analysis\n\nIn this section, we first present a case study illustrating the usability of SBA-XACML policy evaluation process through semantics rules and experiments. Then, we provide the results of the performance analysis comparing our results to the current approaches. We will be utilizing the XACML example presented in Chapter Two, Section 2.6.3.\n\n3.6.1 SBA-XACML Policy Evaluation\n\nIn this section, we provide the generated SBA-XACML based policy and request, and the response of the evaluation process according to the SBA-XACML policy evaluation semantics in Section 3.4. Listing 3.1 contains the generated SBA-XACML based policy corresponding to the XACML one in Listings 2.3 and 2.4 of Chapter Two, Section 2.6.3.\n\nListing 3.1: SBA-XACML Policy for a Bank Service\n\n```\n[1].PS::=<PS1,{P1,P2},{P1>P2},{Permit-overrides},{},{{},{{},{{}}}}>\n[2].P::=<P1,{R1,R2},{R1>R2},{Permit-overrides},{}{Withdraw, Permit, {mailto, string,\nCustomer_service@bank.com}, {subject-id, string, subject-id}, {resource-id, string, resource\n-id}}},{{Jerry, Joe}, {BankService/withdraw}, {Any}}>\n[3].R::=<R1,{{and,{string-equal,{ResourceAttributeDesignator, string, BankService/withdraw\n}}},{string-equal, {SubjectAttributeDesignator, subject-id, string, Bob}}}),{ },{ },{},{{\nPermit}}>\n[4].R::=<R2,{},{{},{{}},{}},{Deny}>\n[5].P::=<P2, {R3,R4,R5}, {R3>R4>R5}, {Permit-overrides}, { },{ },{},{},{}>\n[6].R::=<R3, {string-equal, {ResourceAttributeDesignator, string, BankService/deposit\n}},{ },{ },{},{{Permit}>\n[7].R::=<R4, {and,{string-equal, {ResourceAttributeDesignator, string, BankService/deposit\n}},{string-equal, {SubjectAttributeDesignator, subject-id, string, Joe}}}),{ },{ },{},{{\nPermit}}>\n[8].R::=<R5, {and,{string-equal, {ResourceAttributeDesignator, string, BankService/deposit\n}},{string-equal, {SubjectAttributeDesignator, subject-id, string, Joe}}}),{ },{ },{},{Deny}>\n```\n\nLine 1 is the policy set $PS$. The policy set ID is $PS1$. It has two policies $P1$ and $P2$. $P1$ is ordered before $P2$. The policy combining algorithm is $Permit – Overrides$. \n\n62\nPS1Bank has no reference to other policies. It has no obligations to perform and the target subjects, resources and actions are any. Line 2 is the Withdraw policy. The policy ID is P1. It has two rules R1 and R2. R1 is ordered before R2. The rule combining algorithm is Permit – Overrides. P1 has one obligation to perform and the target subjects are Bob and Jerry, resource is BankService/withdraw and actions are any. Line 3 is the rule R1. The rule ID is R1. R1 has a set of conditions. The conditions are: the subject ID must be equal to Bob and the resource ID must be equal to BankService/withdraw. The target subjects, resources and actions are any. R1 has a permit effect. Line 4 is the rule R2. The rule ID is R2. R2 has no conditions. R2 has no target specified. R2 has a deny effect. Line 5 is the deposit policy. The policy ID is P2. It has three rules R3, R4 and R5. The precedence order is R3, R4 and R5. The rule combining algorithm is permit – overrides. P2 has no obligation to perform and the target elements are not defined. Line 6 is the rule R3. The rule ID is R3. R3 has one condition. The condition states that the resource ID must be equal to BankService/Deposit. The target subjects, resources and actions are not specified. R3 has a permit effect. Line 7 is the rule R4. The rule ID is R4. R4 has a set of conditions. The conditions are: the subject ID must be equal to Joe and the resource ID must be equal to BankService/Deposit. The target subjects, resources and actions are not specified. R4 has a permit effect. Line 8 is the rule R5. The rule ID is R5. R5 has a set of conditions. The conditions are: the subject ID must be equal to Joe and the resource ID must be equal to BankService/Deposit. The target subjects, resources and actions are not specified. R5 has a deny effect.\n\nListing 3.2 contains the generated SBA-XACML request corresponding to one in Listing 2.5 of Chapter Two. The request subject is equal to Bob, resource equal\nBankService/Deposit and action equal execute.\n\nListing 3.2: SBA-XACML Access Request\n\n\\[ [1].Rq1::=\\langle\\{\\text{Bob}\\}, \\{\\text{BankService/Deposit}\\}, \\{\\text{execute}\\} \\rangle \\]\n\nBased on the SBA-XACML policy evaluation semantics in Section 3.4 and its implemented algorithms in Section 3.5, the elaborated framework will evaluate the request \\text{Rq1} in Listing 3.2 with respect to the based policy \\text{PS1} presented in Listing 3.1 generated from Listings 2.3 and 2.4. Since the evaluation of each semantics rule is based on evaluating its premises, we will describe the evaluation steps in order by the premises of policy sets, policies and rules as summarized in Table 10. To avoid repetition and for space limitation, we will present only the matching semantics rules that affect the final decision. The rules in Table 10 should be read from bottom to top as follows:\n\n(1) The based policy is composed of a PolicySet \\text{PS1}. It has \\text{PCA} = \\{\\text{Permit-Overrides}\\}, its target \\text{TR} matches request \\text{Rq1} as illustrated in (2) and it has a policy \\text{P2} that evaluates to \\text{Permit} as depicted in (3). Hence, based on the semantics Rule 15 that applies in this case, all the three premises are satisfied and the final decision is \\text{Permit}.\n\n(2) \\text{PS1} has no target defined which means \\text{TR} = \\{\\} or \\text{TR} = \\{S = \\text{Any} , R = \\text{Any}, A = \\text{Any}\\}. \\text{Rq1} = \\{Sr = \\text{Bob} , Rr = \\text{BankService/Deposit}, Ar = \\text{execute}\\}. By applying semantics Rule 1, Bob is a subset of Any, BankService/Deposit is a subset of Any and execute is a subset of Any, therefore \\text{PS1} matches the request \\text{Rq1}.\n\n(3) Policy \\text{P2} is composed of three rules. It has \\text{RCA} = \\text{Permit-Overrides}, its target \\text{TR} matches with the target of request \\text{Rq1} as illustrated in (4) and it has a rule \\text{R3} that\nTable 10: Results of Semantics-Based Policy Evaluation\n\n<table>\n<thead>\n<tr>\n<th>Step</th>\n<th>Rule</th>\n<th>Premise</th>\n<th>Match</th>\n<th>Eval</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>(6)</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>(5)</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>(4)</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>(3)</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>(2)</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>(1)</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n*evaluates to Permit as depicted in (5). Hence, based on the semantics Rule 6 that applies in this case, all the three premises are satisfied and the evaluation of P2 with respect to Rq1 is Permit.*\n\n**P2** has no target TR defined which means TR = {S = Any, R = Any, A = Any}. Rq1 = {Sr = Bob, Rr = BankService/Deposit, Ar = execute}. By applying semantics Rule 1, Bob is a subset of Any, BankService/Deposit is a subset of Any and execute is a subset of Any, therefore P2 matches the request Rq1.\n\n**P2** has no target TR defined which means TR = {S = Any, R = Any, A = Any}. Rq1 = {Sr = Bob, Rr = BankService/Deposit, Ar = execute}. By applying semantics Rule 1, Bob is a subset of Any, BankService/Deposit is a subset of Any and execute is a subset of Any, therefore P2 matches the request Rq1.\n\n**P2** has no target TR defined which means TR = {S = Any, R = Any, A = Any}. Rq1 = {Sr = Bob, Rr = BankService/Deposit, Ar = execute}. By applying semantics Rule 1, Bob is a subset of Any, BankService/Deposit is a subset of Any and execute is a subset of Any, therefore P2 matches the request Rq1.\n\n**P2** has no target TR defined which means TR = {S = Any, R = Any, A = Any}. Rq1 = {Sr = Bob, Rr = BankService/Deposit, Ar = execute}. By applying semantics Rule 1, Bob is a subset of Any, BankService/Deposit is a subset of Any and execute is a subset of Any, therefore P2 matches the request Rq1.\n\n(4) P2 has no target TR defined which means TR = {S = Any, R = Any, A = Any}. Rq1 = {Sr = Bob, Rr = BankService/Deposit, Ar = execute}. By applying semantics Rule 1, Bob is a subset of Any, BankService/Deposit is a subset of Any and execute is a subset of Any, therefore P2 matches the request Rq1.\n\n(5) The target TR of R3 matches with the target of request Rq1 as illustrated in (6). R3 has\none rule condition $RC = \\{\\text{string-equal,\\{RAD, string, BankService/deposit\\}}\\}$, which means the resource requesting access must be equal to BankService/Deposit. $RC = True$ because the Resource $R$ of $Rq1$ is equal to BankService/Deposit. The rule effect $RE$ of $R3$ is Permit ($RE=\\text{Permit}$). Hence, based on the semantics Rule 3 that applies in this case, all the three premises are satisfied and the evaluation of $R3$ with respect to $Rq1$ is $\\text{Permit}$.\n\n(6) $R3$ has no target defined which means $TR = \\{S = \\text{Any}, R = \\text{Any}, A = \\text{Any}\\}$. $Rq1 = \\{Sr = Bob, Rr = \\text{BankService/Deposit}, Ar = \\text{execute}\\}$. By applying semantics Rule(1), Bob is a subset of Any, BankService/Deposit is a subset of Any and execute is a subset of Any, therefore $R3$ matches the request $Rq1$.\n\nThe response to the request in Listing 3.2 against the based policy in Listing 3.1 is presented in Listing 3.3. The evaluation results of our approach always returns the same results given by XACML Sun PDP [18].\n\nListing 3.3: SBA-XACML Response\n\n\\[ \\langle \\{\\text{permit}\\},\\{\\} \\rangle \\]\n\n3.6.2 Experiments and Performance Analysis\n\nWe have implemented the SBA-XACML framework using PHP. Our experiments were carried out on a notebook running Windows XP SP3 with 3.50GB of memory and dual core 2.8GHz Intel processor. The experiments were performed at 100,000 tests each and the average number was calculated and used. They were conducted on both real world and\nsynthetic policies to show the scalability and performance on very large ones. Synthetic policies are created in such a way that every policy and every rule in the policy set is evaluated to reach the final decision (i.e. taking always the worst case). The Synthetic policy sets range from 400 to 4000 rules which are split evenly over 100 policies. In order to be able to exhaust the entire policy set, we specified (1) a policy combining algorithm Deny-Overrides, (2) rule combining algorithm Deny-Overrides for each policy, (3) the deny rule as the last rule in the policy and (4) non empty target element. Please note that moderate specification (i.e. decision is taking early without checking all the rules) of the synthetic policies will lead to better performance. We compare our proposed framework to the commercial XACML engine Sun PDP [18] and XEngine [12].\n\nThe processing time of Sun PDP consists of XACML policy loading, request loading and request evaluation to provide the decision. There is no pre-processing time for Sun PDP. As for XEngine, the pre-processing time consists of policy loading, numericalization and normalization, while processing time consists of request loading, numericalization and evaluation to provide the decision. Regarding our approach, the pre-processing consists of converting policy set from XACML to SBA-XACML, which is optional and executed only once when deploying the policies. The processing time includes (1) accepting a request and converting it to SBA-XACML, (2) loading policies and (3) evaluating the request to providing the decision. We repeated this policy evaluation process for 100,000 different requests with and without the pre-processing procedures and provided the average evaluation time of synthetic and real world policies.\n\nWe chose not to use the experiments methodology used by XEngine because it does not reflect real world environments. Their tools and experiments show that all the requests\n(i.e. up to 100,000 requests) are received, converted and loaded in the memory at the same\ntime, then evaluated against the already loaded policies. Again as aforementioned, such\nassumption does not always hold since requests can be received from different parties at\nvariant time-space. Fig. 8 contains three real world policies. We included the number\nof rules in each policy set, the average pre-processing time (conversion time) for SBA-\nXACML and XEngine, the average processing time for single-valued and multi-valued\nrequests for SBA-XACML, XEngine and Sun PDP.\n\n<table>\n<thead>\n<tr>\n<th>Policy</th>\n<th>#Rules</th>\n<th>Conversion Time (msec)</th>\n<th>Average Processing Time (msec)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td></td>\n<td>SBA-XACML</td>\n<td>XEngine</td>\n</tr>\n<tr>\n<td>IIIA027</td>\n<td>2</td>\n<td>20</td>\n<td>290</td>\n</tr>\n<tr>\n<td>IIIA028</td>\n<td>4</td>\n<td>27</td>\n<td>313</td>\n</tr>\n<tr>\n<td>Continue-a</td>\n<td>298</td>\n<td>94</td>\n<td>562</td>\n</tr>\n</tbody>\n</table>\n\nFig. 8: Experimental Results on Real-World XACML Policies\n\n3.6.2.1 Policy Evaluation Experimental Results\n\nIn the following, we discuss the experimental results for single-valued and multi-valued\nrequests on both synthetic and real world policies. Fig. 9 shows the results for synthetic\npolicy evaluations for single-valued and multi-valued requests. For single-valued requests,\nFig. 9a shows that our approach is faster than both the XEngine and Sun PDP by 3.2 and 8\ntimes respectively for policy sets with 400 rules, and by 2.4 and 2.7 times faster for policy\nsets with 4000 rules. For multi-valued requests, Fig. 9b shows that our approach is faster\nthan both the XEngine and Sun PDP by 3.5 and 9.4 times respectively for policy sets with\n400 rules, and by 2.5 and 3.5 times faster for policy sets with 4000 rules.\nFig. 9: Synthetic Policy Evaluation\n\nFig. 10: Real Policy Evaluation\n\nFig. 10 shows the results for real world policy evaluation for single-valued and multi-valued requests. Fig. 10a explores that our approach is 8 times faster than XEngine and 39 times faster than the Sun PDP for small policies with less than 10 rules, while it is 7.6 faster than XEngine and 3 times faster than Sun PDP on policies with 300 rules. Fig. 10b shows that our approach is faster by 2.4 times and 6.3 than XEngine and Sun PDP respectively for a policy set with 298 rules, while it is 3.5 times and 15 times faster than XEngine and Sun PDP respectively for small policies with less than 10 rules.\n\n3.6.2.2 Policy Evaluation Experimental Results including Pre-Processing\n\nIn the following, we discuss the conversion time from XACML to SBA-XACML with respect to the XEngine conversion time. The conversion time is referred to as pre-processing time in [12]. The conversion procedure is optional in our approach and required only during the policy deployment. However, the XEngine approach requires this step because the\nconversion includes numericalization and normalization and it is the core of their proposal to improve the evaluation response time. Fig. 11a and Fig. 11b show the conversion time for synthetic and real world policies respectively. Assuming the Synthetic policies are in XACML, the XEngine pre-processing time consumes 2.3 times more than our approach for a policy set with 4000 rules, and 8.5 times more for a policy set with 400 rules. For real policies, the XEngine requires 8 times more than our approach for policy sets with 298 rules, and 10 times more for policy sets with less than 10 rules.\n\nFig. 12 shows the results of the overall processing and pre-processing (i.e. conversion) time of single-valued and multi-valued requests against synthetic policies ranging from 400 to 4000 rules. Fig. 12a shows that our approach outperformed the XEngine by 6 times for small policy sets with 400 rules, and by 2 times for large policy sets with 4000 rules. Fig. 12b illustrates that our approach outperformed the XEngine by 6.1 times for small policy sets with 400 rules, and by 2 times for large policy sets with 4000 rules.\n\nFig. 13 shows the results for the overall processing and pre-processing (i.e. conversion) for single-valued and multi-valued requests against real policies ranging from 2 to 298 rules. Fig. 13a shows that SBA-XACML outperformed the XEngine by 9 times for small policy sets with less than 10 rules and by 4.2 times for medium size policy sets with 300 rules. Fig. 13b illustrates that our approach outperformed the XEngine by 9 times for small...\nFig. 12: Synthetic Policy Evaluation with Policy Conversion\n\nFig. 13: Real Policy Evaluation with Policy Conversion\n\npolicy sets with less than 10 rules, and by 4 times for policy sets with 300 rules.\n\n3.7 Conclusion\n\nIn this chapter, we addressed the problems related XACML complexity and real-time decision evaluation efficiency. In the context, we proposed an SBA-XACML language and a model which supports the evaluation of both XACML and SBA-XACML policies. The language is based on sets and it covers all XACML elements and attributes without any compromise or extension. In addition, we provided the semantics and its corresponding algorithms for policy evaluation. We realized and demonstrate the viability of our proposition by (1) Implementing the model and (2) developing a case study and (3) performing the experimental analysis. Our results show that our solution reduces the response by more than 50 percent when compared to Sun PDP [18] and Xengine [12].\nChapter Four\n\nSBA-XACML Analysis\n\n4.1 Introduction\n\nCreating XACML policies is a simple task to do with existing tools but there is no verification process to alert for access flaws. How do we know if the new policies created do not create conflicts and grant access to the wrong users? How do we verify if recently deleted rules or policies do not create access flaws or conflicts? XACML documents can become very large and complex even when you do not have a complex system. As a result, verifying access policies can become an impossible task to do. The only possible solution for XACML to verify if policies are free of access flaws, conflicts and redundancies, is to test the access of every possible scenario. It is not logical to test the entire system every time you add a new rule or delete a policy. The proposed approach enables policy administrators to automatically analyze access policies and detect access flaws, conflicts and redundancies without much efforts and resources.\nThe rest of the chapter is organized as follows. In Section 4.2, we present the analysis semantics. In Section 4.3, we illustrate the SBA-XACML analysis algorithms. In Section 4.4, we exhibit a case study to show the effectiveness of our proposition. In Section 4.5, we conclude the chapter.\n\n4.2 Policy Analysis Semantics\n\nIn this section, we present the formal semantics of a SBA-XACML policy analysis following the above inference rule structure and deductive logic. Given a policy $P$, the analysis report $RP$ is derived by the evaluation $\\rightarrow_{eval}$ of all premises combined between each other using designated operators $op$ as follows:\n\n\\[\n(premise_1) \\ op \\ (premise_2) \\ op \\ ... \\ op \\ (premise_n)\n\\]\n\n\\[\n< P1, P2 > \\rightarrow_{eval} RP\n\\]\n\nThe policy and rule analysis semantics rules, which constitute the premises in the above rule, have also similar structure and follows the deductive logic until reaching the basic defined premise (i.e. condition). Throughout the rest of the thesis, please note the difference between a semantic rule that express the analysis at a particular level, and a policy rule which is a construct in SBA-XACML. All the semantics rules follow the bottom up structure, where all the common ones are presented first, then followed by the rule level, policy level and policy set level ones. In this context, we start first by defining the $Subset$ and $IntersectionFunction$ semantics rule since it will be used throughout all levels.\n4.2.1 Subset & Intersection Function\n\nIn this section, we present the subset and intersection semantics rules for SBA-XACML rule \\( R_1 \\) with subject set \\( S_1 \\), resource set \\( R_1 \\) and action set \\( A_1 \\) and SBA-XACML rule \\( R_2 \\) with subject set \\( S_2 \\), resource set \\( R_2 \\) and action set \\( A_2 \\). The semantics is determined by comparing the subject set \\( S_1 \\) with subject set \\( S_2 \\), resource set \\( R_1 \\) with resource set \\( R_2 \\) and action set \\( A_1 \\) with action set \\( A_2 \\).\n\nTable 11: Subset Function Semantics Rules\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Condition</th>\n<th>Conclusion</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>((S_1 \\subseteq S_2) \\land (R_1 \\subseteq R_2) \\land (A_1 \\subseteq A_2))</td>\n<td>(<(TR_1, TR_2)> \\vdash True_{subset})</td>\n</tr>\n<tr>\n<td>2</td>\n<td>((S_1 \\not\\subseteq S_2) \\lor (R_1 \\not\\subseteq R_2) \\lor (A_1 \\not\\subseteq A_2))</td>\n<td>(<(TR_1, TR_2)> \\vdash False_{subset})</td>\n</tr>\n</tbody>\n</table>\n\nRules 1 and 2 in Table 11 describe the different cases of subset rules. In Rule 1, A target \\( TR_1 \\) is a subset of target \\( TR_2 \\) if target \\( TR_1 \\) subject set \\( S_1 \\) is a subset of target \\( TR_2 \\) subject set \\( S_2 \\) and target \\( TR_1 \\) resource set \\( R_1 \\) is a subset of target \\( TR_2 \\) resource set \\( R_2 \\) and target \\( TR_1 \\) action set \\( A_1 \\) is a subset of target \\( TR_2 \\) action set \\( A_2 \\). In Rule 2, A target \\( TR_1 \\) is not a subset of target \\( TR_2 \\) if target \\( TR_1 \\) subject set \\( S_1 \\) is not a subset of target \\( TR_2 \\) subject set \\( S_2 \\) or target \\( TR_1 \\) resource set \\( R_1 \\) is not a subset of target \\( TR_2 \\) resource set \\( R_2 \\) or target \\( TR_1 \\) action set \\( A_1 \\) is a subset of target \\( TR_2 \\) action set \\( A_2 \\).\n\nRules 3 and 4 in Table 12 describe the different cases of intersection rules. In Rule 3, two targets \\( TR_1 \\) and \\( TR_2 \\) intersect if target \\( TR_1 \\) subject set \\( S_1 \\) and target \\( TR_2 \\) subject set \\( S_2 \\) share common elements and target \\( TR_1 \\) resource set \\( R_1 \\) and target \\( TR_2 \\) resource set \\( R_2 \\)\n### Table 12: Intersection Function Semantics Rules\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Semantics</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>(((S_1 \\cap S_2 \\neq \\emptyset) ) & (((R_1 \\cap R_2 \\neq \\emptyset)) & (((A_1 \\cap A_2 \\neq \\emptyset)))</td>\n<td>(< TR_1, TR_2 > \\vdash intersect True)</td>\n</tr>\n<tr>\n<td>((S_1 \\cap S_2 = \\emptyset) \\lor ((R_1 \\cap R_2 = \\emptyset) \\lor ((A_1 \\cap A_2 = \\emptyset))</td>\n<td>(< TR_1, TR_2 > \\vdash intersect False)</td>\n</tr>\n</tbody>\n</table>\n\nshare common elements and target \\(TR1\\) action set \\(A1\\) and target \\(TR2\\) action set \\(A2\\) share common elements. In Rule 4, two targets \\(TR1\\) and \\(TR2\\) do not intersect if target \\(TR1\\) subject set \\(S1\\) and target \\(TR2\\) subject set \\(S2\\) share no common elements or target \\(TR1\\) resource set \\(R1\\) and target \\(TR2\\) resource set \\(R2\\) share no common elements or target \\(TR1\\) action set \\(A1\\) and target \\(TR2\\) action set \\(A2\\) share no common elements.\n\n### 4.2.2 Access Flaw Detection\n\nIn this section, we present the policy access flaw analysis semantics rules for SBA-XACML policy set.\n\nSemantics Rules 5, 6, 7 and 8 in Table 13 describe the different access flaw analysis cases for a policy set \\(PS\\). In Rule 5, two rules \\(R1\\) and \\(R2\\) return flaw if \\(R2\\) target \\(TR2\\) is a subset of rule \\(R1\\) target \\(TR1\\) (see details in semantics Rule 1) and rule \\(R2\\) rule condition \\(RC2\\) is a subset of rule \\(R1\\) rule condition \\(RC1\\) and both rules \\(R1\\) and \\(R2\\) have the same rule effect \\(RE1\\) equal \\(RE2\\). In Rule 6, for every pair of rules \\(R1\\) and \\(R2\\) in policy \\(P\\) such that \\(R1\\) and \\(R2\\) are appended to the Flaw Set \\(FS\\) if \\(R1\\) and \\(R2\\) evaluate to flaw (see details in semantics rule 5). In Rule 7, given a pair of policies \\(P1, P2\\) in policy set \\(PS\\), \\(P1\\) and \\(P2\\) are appended\nTable 13: Rules of Access Flaw Detection Semantics\n\n\\[\n\\begin{align*}\n\\langle TR2, TR1 \\rangle \\vdash & \\text{subset True} \\land (RC2 \\subseteq RC1) \\land (RE1 = RE2) \\\\\n& \\Rightarrow \\text{Flaw}_{R1, R2} \\\\\n(\\forall R1, R2 \\in SR; FS \\leftarrow FS \\cup \\langle R1, R2 \\rangle \\Rightarrow \\text{Flaw}_{R1, R2})\n\\end{align*}\n\\]\n\n(Rule 5)\n\n\\[\n\\begin{align*}\n\\langle P1, P2 \\rangle \\Rightarrow & \\text{Flaw}_{P1, P2} \\\\\n(\\forall P \\in SP; FS \\leftarrow FS \\cup \\langle P \\rangle \\Rightarrow \\text{Flaw}_{P1, P2}) \\cup (\\forall P1, P2 \\in SP; FS \\leftarrow FS \\cup \\langle P1, P2 \\rangle \\Rightarrow \\text{Flaw}_{P1, P2})\n\\end{align*}\n\\]\n\n(Rule 6)\n\n\\[\n\\begin{align*}\n\\langle PS \\rangle \\Rightarrow & \\text{Flaw}_{PS, FA} \\\\\n(\\forall P \\in SP; FS \\leftarrow FS \\cup \\langle P \\rangle \\Rightarrow \\text{Flaw}_{PS, FA})\n\\end{align*}\n\\]\n\n(Rule 7)\n\n\\[\n\\begin{align*}\n& \\Rightarrow \\text{Flaw}_{R1, R2} \\\\\n(\\forall R1, R2 \\in SR; FS \\leftarrow FS \\cup \\langle R1, R2 \\rangle \\Rightarrow \\text{Flaw}_{R1, R2})\n\\end{align*}\n\\]\n\n(Rule 8)\n\nto the Flaw Set FS if the rule combining of P1 is equal to the rule combining of P2 and the targets of P1 and P2 intersect (see details in semantics Rule 3) and there exists R1 in P1 and R2 in P2 such that R1 and R2 evaluate to flaw and appended to the Flaw Set FS (see details in semantics Rule 5). In Rule 8, given policy set PS, the Flaw Set FS is the union of all flaws between any two flawed rules R1, R2 in one policy and between two flawed rules R1, R2 from two different policies and every two flawed policies P1 and P2. (see details in semantics rule 6,7).\n\n4.2.3 Redundancy Detection\n\nIn this section, we present the policy Redundant analysis semantics rules for SBA-XACML policy set.\n\nSemantics Rules 9,10,11 and 12 in Table 14 describe the different redundant analysis cases for a policy set PS. In Rule 9, two rules R1 and R2 are redundant if R1 target TR1 and rule R2 target TR2 intersect (see details in semantics Rule 3) and rule R1 rule condition\nTable 14: Rules of Redundancy Detection Semantics\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>9</td>\n<td>(< TR_2, TR_1 > \\triangleright intersect True \\land (\\exists RC_2 \\cap RC_1 \\neq 0) \\land (RE_1 = RE_2) \\rightarrow < R_1, R_2 > \\rightarrow RA(R_1, R_2))</td>\n</tr>\n<tr>\n<td>10</td>\n<td>(\\forall R_1, R_2 \\in SR; RS \\leftarrow RS \\cup (< R_1, R_2 > \\rightarrow RA(R_1, R_2)))</td>\n</tr>\n<tr>\n<td>11</td>\n<td>((RCA.P_1 = RCA.P_2) \\land (< TR_1, TR_2 > \\triangleright intersect True) \\land (\\forall R_1 \\in SR_1, R_2 \\in SR_2; RS \\leftarrow RS \\cup (< R_1, R_2 > \\rightarrow RA(R_1, R_2)))</td>\n</tr>\n<tr>\n<td>12</td>\n<td>(\\forall P \\in SP; RS \\leftarrow RS \\cup (< P > \\rightarrow RA(RS)) \\cup (\\forall P_1, P_2 \\in SP; RS \\leftarrow RS \\cup < P_1, P_2 > \\rightarrow RA(RS)))</td>\n</tr>\n</tbody>\n</table>\n\nRC1 and rule R2 rule condition RC2 intersects and both rules R1 and R2 have the same rule effect RE1 equal RE2. In Rule 10, for every pair of rules R1 and R2 in policy P such that R1 and R2 are appended to the Redundant Set RS if R1 and R2 are redundant (see details in semantics rule 9). In Rule 11, given a pair of policies P1, P2 in policy set PS, P1 and P2 are appended to the Redundant Set RS if the rule combining of P1 is equal to the rule combining of P2 and the targets of P1 and P2 intersect (see details in semantics Rule 3) and there exists R1 in P1 and R2 in P2 such that R1 and R2 are redundant and appended to the Redundant Set RS (see details in semantics Rule 9). In Rule 12, given policy set PS, the Redundant Set RS is the union of all redundancies between any two redundant rules R1, R2 in one policy and between two redundant rules R1, R2 from two different policies and every two redundant policies P1 and P2. (see details in semantics rule 10,11).\n4.2.4 Conflict detection\n\nIn this section, we present the policy conflict analysis semantics rules for SBA-XACML policy set.\n\nTable 15: Rules of Conflict Detection Semantics\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Description</th>\n</tr>\n</thead>\n</table>\n| Rule 13 | \\[\n\\begin{align*}\n< T_R1,T_R2 > & \\vdash \\text{intersect True} \\land (\\{\\text{RC}_1 \\land \\text{RC}_2 \\neq \\emptyset\\} \\land (\\text{RE}_1 \\neq \\text{RE}_2)) \\\\\n\\text{RC}_1 \\cap \\text{RC}_2 & \\neq \\emptyset \\\\\n\\text{RE}_1 & \\neq \\text{RE}_2 \\\\\n< R_1,R_2 > & \\rightarrow \\text{Conflict}_{R_1,R_2} \\\\\n(\\forall R_1,R_2 \\in \\text{SR}; \\text{RS} \\leftarrow \\text{CS} \\cup (\\langle R_1,R_2 > \\rightarrow \\text{Conflict}_{R_1,R_2})) \\\\\n\\end{align*}\n\\] |\n\n| Rule 14 | \\[\n\\begin{align*}\n< P > & \\rightarrow \\text{CS} \\quad \\text{PCA} \\\\\n(\\forall P_1,P_2 \\in \\text{SP}; \\text{CS} \\leftarrow \\text{CS} \\cup (\\langle P_1 > \\rightarrow \\text{CS}) \\cup (\\langle P_2 > \\rightarrow \\text{CS}) \\cup (\\langle P_1,P_2 > \\rightarrow \\text{CS})) \\\\\n\\end{align*}\n\\] |\n\n| Rule 15 | \\[\n\\begin{align*}\n< P_1,P_2 > & \\rightarrow \\text{CS} \\quad \\text{PCA} \\\\\n(\\forall P_1,P_2 \\in \\text{SP}; \\text{CS} \\leftarrow \\text{CS} \\cup (\\langle P_1 > \\rightarrow \\text{CS}) \\cup (\\langle P_2 > \\rightarrow \\text{CS}) \\cup (\\langle P_1,P_2 > \\rightarrow \\text{CS})) \\\\\n\\end{align*}\n\\] |\n\n| Rule 16 | \\[\n\\begin{align*}\n< P_1,P_2 > & \\rightarrow \\text{CS} \\quad \\text{PCA} \\\\\n(\\forall P_1,P_2 \\in \\text{SP}; \\text{CS} \\leftarrow \\text{CS} \\cup (\\langle P_1 > \\rightarrow \\text{CS}) \\cup (\\langle P_2 > \\rightarrow \\text{CS}) \\cup (\\langle P_1,P_2 > \\rightarrow \\text{CS})) \\\\\n\\end{align*}\n\\] |\n\nSemantics Rules 13,14,15 and 16 in Table 15 describe the different conflict analysis cases for a policy set PS. In Rule 13, two rules R1 and R2 conflict if R1 target TR1 and rule R2 target TR2 intersect (see details in semantics Rule 3) and rule R1 rule condition RC1 and rule R2 rule condition RC2 intersects and rule R1 with effect RE1 which is the opposite of rule R2 with effect RE2. In Rule 14, for every pair of rules R1 and R2 in policy P such that R1 and R2 are appended to the Conflict Set CS if R1 and R2 conflict (see details in semantics rule 13). In Rule 15, given a pair of policies P1, P2 in policy set PS, P1 and P2 are appended to the Conflict Set CS if the rule combining of P1 is equal to the rule combining of P2 and the targets of P1 and P2 intersect (see details in semantics Rule 3) and there exists R1 in P1 and R2 in P2 such that R1 and R2 conflicted and appended to\nthe Conflict Set $CS$ (see details in semantics Rule 13). In Rule 16, given policy set $PS$, the Conflict Set $CS$ is the union of all conflicts between any two conflicting rules $R1$, $R2$ in one policy and between two conflicting rules $R1$, $R2$ from two different policies and every two conflicting policies $P1$ and $P2$. (see details in semantics rule 14,15).\n\n4.3 Policy Analysis Algorithms\n\nIn this section, we present the algorithms realizing the SBA-XACML policy analysis semantics. The analysis module is divided into three algorithms: (1) the Rule Analysis Algorithm is presented in Algorithm 4, (2) the Policy Analysis Algorithm in Algorithm 5 and (3) PolicySet Analysis Algorithm in Algorithm 6.\n\n4.3.1 Rule Analysis Algorithm\n\nIn this subsection, We present the Rule Analysis Algorithm in Algorithm 4. It takes rules $R1$ and $R2$ as input. It checks for flaws, conflicts and redundancies between $R1$ and $R2$. The output is the Flaw, Conflict, Redundant or null.\n\nThe Rule Analysis in algorithm 4 takes two rules $R1$ and $R2$ as input and compares their targets, Rule conditions and rule effects to determine if there exists any flaws, conflicts and redundancies between the two rules. It returns the proper response to the Policy Analysis Algorithm in Algorithm 5. If the target of rule $R2$ is a subset of the target of rule $R1$ (line 3), the rule condition set of $R2$ is a subset of the rule condition set of $R1$ (line 5), $R1$ and $R2$ have the same effect (line 7) and $R1$ takes a precedent order over $R2$ then the rule $R1$ is considered as access control flaw and it should be removed. If the subject set of $R1$\nAlgorithm 4 Rule_Analysis($R_1$, $R_2$)\n\nInput : Two Rules $R_1$ with Target $TR_1 = \\{S_1, R_1, A_1\\}$, rule condition $RC_1$, rule effect $RE_1$ and $R_2$ with Target $TR_2 = \\{S_2, R_2, A_2\\}$, rule condition $RC_2$, rule effect $RE_2$\n\nOutput : Rule analysis $\\in \\{\\text{Flaw, Conflict, Redundant or Null}\\}$\n\n1: Flaw check if a rule $R_2$ is a subset of $R_1$\n2: // Is $R_2$ target is a subset or equal to $R_1$ target\n3: if $(S_2 \\subseteq S_1) \\land (R_2 \\subseteq R_1) \\land (A_2 \\subseteq A_1)$ then\n4: // Check rule conditions for $R_1$ and $R_2$\n5: if $(RC_2 \\subseteq RC_1)$ then\n6: // Check if $R_1$ and $R_2$ have the same effect\n7: if $(RE_1 = RE_2)$ then\n8: // $R_2$ is a subset of $R_1$\n9: return \"Flaw\";\n10: end if\n11: end if\n12: end if\n13: // Do the targets for $R_1$ and $R_2$ share common subjects, resources, actions\n14: if $((S_1 \\cap S_2) \\neq \\emptyset) \\land ((R_1 \\cap R_2) \\neq \\emptyset) \\land ((A_1 \\cap A_2) \\neq \\emptyset)$ then\n15: // Check if rule conditions for $R_1$ and $R_2$ intersect\n16: if $(RC_1 \\cap RC_2) \\neq \\emptyset)$ then\n17: // check if $R_1$ and $R_2$ have opposite effect\n18: if $(RE_1 \\neq RE_2)$ then\n19: // $R_1$ and $R_2$ Conflict with each other\n20: return \"Conflict\";\n21: else\n22: // $R_1$ and $R_2$ have same effect\n23: return \"Redundant\";\n24: end if\n25: end if\n26: end if\n27: return ;\n\nintersect with subject set of $R_2$, resource set of $R_1$ intersect with resource set of $R_2$ and\naction set of $R_1$ intersect with action set of $R_2$ (line 13) and $R_1$ and $R_2$ have opposite effect (line 17) then $R_1$ conflicts with $R_2$ but if $R_1$ and $R_2$ have the same effect then $R_1$ and $R_2$ are redundant. Empty set is returned if no issues were found between the two rules (line 26).\n4.3.2 Policy Analysis Algorithm\n\nIn this subsection, We present the policy analysis algorithm in Algorithm 5. It takes two policies \\( P1 \\) and \\( P2 \\) as input. The output is Flaw Set \\( FS \\) of all flaws at rule and policy level, Conflict Set \\( CF \\) and Redundancy Set \\( RS \\).\n\nThe policy analysis algorithm in Algorithm 5 takes two policies \\( P1 \\) and \\( P2 \\) as input and produces a set of all access flaws \\( FS \\), conflicts \\( CS \\) and redundancies \\( RS \\). The algorithm is composed of two parts. The first part of the algorithm checks for flaws, conflicts and redundancies within each policy (lines 2-18). It calls the rule analysis algorithm in Algorithm 4 on (line 5) to check every two rules for flaws, conflicts and redundancies. The returned response from the Rule Analysis Algorithm is appended to the proper set (lines 7-15). The second part of the algorithm checks for flaws, conflicts and redundancies between rules from different policies if the rule combining of both policies \\( P1 \\) and \\( P2 \\) have the same combining algorithms and the targets of both policies \\( P1 \\) and \\( P2 \\) intersect which means the subjects of \\( P1 \\) share common subjects with \\( P2 \\) subjects, resources of \\( P1 \\) share common resources with \\( P2 \\) resources, and actions of \\( P1 \\) share common actions with \\( P2 \\) actions (lines 20-43). It calls the rules analysis on (line 26) to check every two rules \\( R1 \\) from \\( P1 \\) and \\( R2 \\) from \\( P2 \\) for flaws, conflicts and redundancies. The returned response from the Rule Analysis is appended to the proper set.\n\n4.3.3 PolicySet Analysis Algorithm\n\nIn this subsection, We present the PolicySet Analysis Algorithm in Algorithm 6. It takes a policy set \\( PS \\) as input. It calls the Policy Analysis Algorithm presented in Algorithm 5 to\nAlgorithm 5 Policy_Analysis($P_1, P_2$)\n\n**Input**: Policy $P_1$ with Target $TR_1 = \\{S_1, R_1, A_1\\}$ and $P_2$ with Target $TR_2 = \\{S_2, R_2, A_2\\}$\n\n**Output**: Flaw Set $FS$, Conflict Set $CS$ and Redundancy Set $RS$\n\n1: //Check rules in each policy\n2: for $l := 1$ to $P_1$ Number of Rules - 1 do\n3: for $i := 1$ to $P_1$ Number of Rules do\n4: RA = RULE_ANALYSIS($R_{li}, R_{lj}$);\n5: // RA response\n6: if (RA = \"Flaw\") then\n7: $FS = FS \\cup $ Flaw$R_{li}, R_{lj}$;\n8: end if\n9: if (RA = \"Redundant\") then\n10: $RS = RS \\cup $ Redundant$R_{li}, R_{lj}$;\n11: end if\n12: if (RA = \"Conflict\") then\n13: $CS = CS \\cup $ Conflict$R_{li}, R_{lj}$;\n14: end if\n15: end for\n16: end for\n17: end for\n18: //Compare Rule Combining of $P_1$ and $P_2$\n19: if ($RCA_{P_1} = RCA_{P_2}$) then\n20: //Common subjects, Resources and Actions from $P_1$ and $P_2$\n21: if (($S_1 \\cap S_2) \\neq \\emptyset ) \\land ((R_1 \\cap R_2) \\neq \\emptyset ) \\land ((A_1 \\cap A_2) \\neq \\emptyset )$ then\n22: // Check rules for Conflicts, Flaws and Redundancies\n23: for $l := 1$ to $P_1$ Number of Rules do\n24: for $m := 1$ to $P_2$ Number of Rules do\n25: RA = RULE_ANALYSIS($R_{li}, R_{mm}$);\n26: // RA response\n27: if (RA = \"Flaw\") then\n28: $FS = FS \\cup $ Flaw$R_{li}, R_{mm}$;\n29: $FS = FS \\cup $ Flaw$P_1, P_2$;\n30: end if\n31: if (RA = \"Conflict\") then\n32: $CS = CS \\cup $ Conflict$R_{li}, R_{mm}$;\n33: $CS = CS \\cup $ Conflict$P_1, P_2$;\n34: end if\n35: if (RS = \"Redundant\") then\n36: $RS = RS \\cup $ Redundant$R_{li}, R_{mm}$;\n37: $RS = RS \\cup $ Redundant$P_1, P_2$;\n38: end if\n39: end for\n40: end for\n41: end if\n42: end if\n43: return ;\nanalyze the policies at the middle layer in the based policy. The output the analysis report which contains all Flaws at the policy and rule level $FS$, Conflicts $CS$ and Redundancies $RS$.\n\n**Algorithm 6 PolicySet_Analysis($PS$)**\n\n**Input**: A Policy Set PS \n**Output**: Analysis report\n\n1: // Initialize sets for Flaws, Redundancies and Conflicts \n2: Global $FS = \\emptyset$; $RS = \\emptyset$; $CS = \\emptyset$; \n3: //Loop through policies in PS \n4: for $i := 1$ to $PS_{NumberofPolices}$ do \n5: for $j := i + 1$ to $PS_{NumberofPolices}$ do \n6: // Call Policy Analysis \n7: $PA = POLICY\\_ANALYSIS(P_i, P_j)$; \n8: end for \n9: end for\n\nThe PolicySet Analysis Algorithm in Algorithm 6 takes a policy set $PS$ as input and produces a report of all access flaws between policies and rules. It initializes global set $FS, CS$ and $RS$ on (line 2) for appending flaws, conflicts and redundancies found at both policy and rule levels. It calls the Policy Analysis Algorithm in Algorithm 5 on (line 7) for checking flaws, conflicts and redundancies between every two policies.\n\n### 4.4 Case Study: SBA-XACML Policy Analysis\n\nIn this section, we present a case study illustrating the usability of SBA-XACML policy analysis process through semantics. We will be utilizing the XACML example presented in Chapter Two, Section 2.6.3, Listings 2.3 and 2.4. Listing 4.1 contains the generated SBA-XACML based policy corresponding the listings mentioned above.\nListing 4.1: SBA-XACML Policy for a Bank Service\n\n```\n[1].PS := <PS1, {P1,P2}, {P1>P2}, {Permit-overrides}, {}, {}, {}>\n[2].P := <P1, {R1,R2}, {R1>R2}, {Deny-overrides}, {}, {}, {}>\n[3].R := <R1, {and, {string-equal, {ResourceAttributeDesignator, string, BankService/withdraw}}, {string-equal, {SubjectAttributeDesignator, subject-id, string, Bob}}}, {}, {}, {}, {Permit}>\n[4].R := <R2, {}, {}, {}, {}, {Deny}>\n[5].P := <P2, {R3,R4,R5}, {R3>R4>R5}, {Permit-overrides}, {}, {}, {}>\n[6].R := <R3, {string-equal, {ResourceAttributeDesignator, string, BankService/deposit}}, {}, {}, {}, {Permit}>\n[7].R := <R4, {and, {string-equal, {RAD, string, BankService/deposit}}, {string-equal, {SubjectAttributeDesignator, subject-id, string, Joe}}}, {}, {}, {}, {Permit}>\n[8].R := <R5, {and, {string-equal, {RAD, string, BankService/deposit}}, {string-equal, {SubjectAttributeDesignator, subject-id, string, Joe}}}, {}, {}, {}, {Deny}>\n```\n\nLine 1 is the policy set PS. The policy set ID is PS1. It has two policies P1 and P2. P1 is ordered before P2. The policy combining algorithm is Permit – Overrides. PS1 has no reference to other policies. It has no obligations to perform and the target subjects, resources and actions are any. Line 2 is the policy P1. The policy ID is P1. It has two rules R1 and R2. R1 is ordered before R2. The rule combining algorithm is deny – Overrides. P1 has no obligations and no target. Line 3 is the rule R1. The rule ID is R1. R1 has a set of conditions. The conditions are: the subject ID must be equal to Bob and the resource ID must be equal to BankService/withdraw. The target subjects, resources and actions are any. R1 has a permit effect. Line 4 is the rule R2. The rule ID is R2. R2 has no conditions. R2 has no target specified. R2 has a deny effect. Line 5 is the policy P2. The policy ID is P2. It has three rules R3, R4 and R5. The precedence order is R3, R4 and R5. The rule combining algorithm is permit – overrides. P2 has no obligation to perform and the target elements are not defined. Line 6 is the rule R3. The rule ID is R3. R3 has one condition. The condition states that the resource ID must be equal to BankService/Deposit. The target subjects, resources and actions are not specified. R3 has a permit effect. Line 7 is the rule R4. The rule ID is R4. R4 has a set of conditions. The conditions are: the subject ID must be equal to Joe and the resource\nID must be equal to BankService/Deposit. The target subjects, resources and actions are not specified. R4 has a permit effect. Line 8 is the rule R5. The rule ID is R5. R5 has a set of conditions. The conditions are: the subject ID must be equal to Joe and the resource ID must be equal to BankService/Deposit. The target subjects, resources and actions are not specified. R5 has a deny effect.\n\nBased on the SBA-XACML policy analysis semantics in Section 4.2, the elaborated framework will analyze the based policy PSI presented in Listings 4.1 for access flaws. Since the analysis of each semantics rule is based on analyzing its premises, we will describe the analysis steps in order by the premises of policy sets, policies and rules.\n\n### 4.4.1 Access Flaw Detection\n\nIn this section, we show the access flaw analysis steps and provide the results for policy set PSI based on the formal analysis semantics presented in 4.2.\n\nPolicySet PSI flaw analysis starts here, hence Our options are limited to Rule 8\n\n#### Step 1. (PSI-Premise1 Evaluation)\n\nRule 8 premise 1 requires the analysis of every policy individually to determine the results of premise 1. PSI has two policies P1 and P2. Since P1 takes a precedence order over P2 then the analysis starts with P1. The evaluation of PSI-Premise1 limits our options to Rule 6.\n\n#### Step 1.1. (P1-Analysis)\n\nP1 Analysis starts here.\nStep 1.1.1. (P1-Premise1 Evaluation)\n\nRule 6 requires analysis of rules to determine the results. P1 has two rules R1 and R2.\n\nThe results of P1-premise1 depends on the evaluation of Rule 5.\n\nStep 1.1.1.1 (R1,R2 - Analysis)\n\nRules R1 and R2 Analysis starts here.\n\nStep 1.1.1.1.1 (R1,R2-Premise1 Evaluation)\n\nBoth R1 and R2 have no targets defined which means\n\nTR1 = \\{\\{\\text{Any}\\}, \\{\\text{Any}\\}, \\{\\text{Any}\\}\\} and TR2 = \\{\\{\\text{Any}\\}, \\{\\text{Any}\\}, \\{\\text{Any}\\}\\}.\n\nBy applying subset semantics Rule(1):\n\n\\[(\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\}) \\land (\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\}) \\land (\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\})\\]\n\n\\[\\underbrace{<(TR2, TR1)>}_{\\text{subset}} \\vdash \\text{True}\\]\n\nTargets TR1 and TR2 are the same therefore TR2 is subset or equal to TR1.\n\nStep 1.1.1.1.2 (R1,R2-Premise2 Evaluation)\n\nRule R2 has no conditions defined, RC2 = \\{} and rule R1 has 2 conditions, RC1 = \\{\\text{and,}\\{\\text{string-equal,RAD,string,BankService/withdraw}\\},\\{\\text{string-equal,SAD,subject-id,string,Bob}\\}\\}, which means that the resource must be equal to BankService/withdraw and subject must be equal to Bob. RC2 is not a subset of RC1 because RC2 has no restrictions on any resources or subjects.\n\nPremise 1 of R1,R2 is satisfied, while Premise 2 is not. At this stage, the evaluation of Premise 3 is not needed anymore since the semantics Rule (5) applies:\n\nBased on the response from Rule (5), the returned response for R1 and R2 is null.\n(\\langle T R 2, T R 1 > \\quad \\vdash_{\\text{subset}} T r u e \\rangle \\land (R C 2 \\not\\subseteq R C 1)\n\n< R 1, R 2 > \\rightarrow_{R . F A} \\text{null}\n\nRules \\text{R1} and \\text{R2} Analysis ends here.\n\nSince the analysis of Rules \\text{R1} and \\text{R2} returned null, therefore no flaws added to the Flaw Set \\text{FS}. The results from Rule (6) \\text{FS} = \\{\\}.\n\nPolicy \\text{P1} Analysis ends here.\n\nFlaw Set \\text{FS} = \\{\\}.\n\nStep 1.2. (P2-Analysis)\n\n\\text{P2} Analysis starts here.\n\nStep 1.2.1. (P2-Premise1 Evaluation)\n\nRule 6 requires analysis of rules to determine the results. \\text{P1} has three rules \\text{R3}, \\text{R4} and \\text{R5}. The results of P2-premise1 depends on the evaluation of Rule 5.\n\nStep 1.2.1.1 (R3,R4-Analysis)\n\nRules \\text{R3} and \\text{R4} Analysis starts here.\n\nStep 1.2.1.1.1 (R3,R4-Premise1 Evaluation)\n\nBoth \\text{R3} and \\text{R4} have no targets defined which means TR3 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\} and TR4 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\}. By applying subset semantics Rule(1):\n\n(\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\}) \\land (\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\}) \\land (\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\})\n\n\\langle (T R 4, T R 3) \\quad \\vdash_{\\text{subset}} T r u e \\rangle\n\nTargets \\text{TR3} and \\text{TR4} are the same therefore \\text{TR4} is subset or equal to \\text{TR3}.\nStep 1.2.1.1.2 (R3,R4-Premise2 Evaluation)\n\nRule $R3$ has one condition defined,\n\n$RC3 = \\{\\text{string-equal}, \\{\\text{RAD}, \\text{string}, \\text{BankService/deposit}\\}\\}$, which means the resource must be equal to BankService/deposit and rule $R4$ has two conditions,\n\n$RC4 = \\{\\text{and}, \\{\\text{string-equal}, \\{\\text{RAD}, \\text{string}, \\text{BankService/withdraw}\\}\\}, \\{\\text{string-equal}, \\{\\text{SAD}, \\text{subject-id}, \\text{string}, \\text{Joe}\\}\\}\\}$, which means that the resource must be equal to BankService/withdraw and subject must be equal to Joe. $RC4$ is a subset of $RC3$ because both require the resource to be BankService/withdraw and $RC4$ limits the subject while $RC3$ accepts any subject.\n\nStep 1.2.1.1.3 (R3,R4-Premise3 Evaluation)\n\nBoth $R3$ and $R4$ have the same effect. All premises of Rule (5) are satisfied. By applying Rule (5):\n\n$$\n(< TR4, TR3 > \\models True) \\land (RC4 \\subseteq RC3) \\land (RE3 = RE4) \\\\\n\\therefore < R3, R4 > \\rightarrow_{R,FA} Flaw_{R3,R4}\n$$\n\nBased on the response from Rule (5), the returned response for $R3$ and $R4$ is $Flaw_{R3,R4}$.\n\nRules $R3$ and $R4$ Analysis ends here.\n\nFlaw Set $FS = \\{Flaw_{R3,R4}\\}$.\n\nStep 1.2.1.2 (R3,R5-Analysis)\n\nRules $R3$ and $R5$ Analysis starts here.\nStep 1.2.1.2.1 (R3,R5-Premise1 Evaluation)\n\nBoth $R3$ and $R5$ have no targets defined which means\n\n$TR3 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\}$ and $TR5 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\}$.\n\nBy applying subset semantics Rule(1):\n\n\\[\n\\begin{align*}\n(\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\}) \\land (\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\}) \\land (\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\}) \\\\\n\\hline\n\\end{align*}\n\\]\n\n\\[\n< (TR5, TR3) > \\quad \\downarrow_{\\text{subset}} \\quad True\n\\]\n\nTargets $TR3$ and $TR5$ are the same therefore $TR5$ is subset or equal to $TR3$.\n\nStep 1.2.1.2.2 (R3,R5-Premise2 Evaluation)\n\nRule $R3$ has one conditions defined,\n\n$RC3 = \\text{string-equal,RAD,string,BankService/deposit}$, which means the resource must be equal to BankService/deposit and rule $R5$ has 2 conditions,\n\n$RC5 = \\{\\text{and},\\{\\text{string-equal},\\{\\text{RAD},\\text{string},\\text{BankService/withdraw}\\}\\},$\n\n$\\{\\text{string-equal},\\{\\text{SAD,subject-id,string},\\text{Joe}\\}\\}\\}$, which means that the resource must be equal to BankService/withdraw and subject must be equal to Joe. $RC5$ is a subset of $RC3$ because both require the resource to be BankService/withdraw and RC5 limits the subject while RC3 accepts any subject.\n\nStep 1.2.1.2.3 (R3,R5-Premise3 Evaluation)\n\nRule $R3$ has the opposite effect of rule $R5$. $R3,R5$ Premises 1 and 2 are satisfied, while Premise 3 is not. Applying semantics Rule (5):\n\nBased on the response from Rule (5), the returned response for $R3$ and $R5$ is null.\n\\((< TR5, TR3 > \\vdash True) \\land (RC5 \\subseteq RC3) \\land (RE3 \\neq RE5)\\)\n\n\\(< R3, R5 > \\xrightarrow{R.FA} null\\)\n\nRules R3 and R5 Analysis ends here.\n\n**Step 1.2.1.3 (R4,R5-Analysis)**\n\nRules R4 and R5 Analysis starts here.\n\n**Step 1.2.1.3.1 (R4,R5-Premise1 Evaluation)**\n\nBoth R4 and R5 have no targets defined which means\n\n\\(TR4 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\}\\) and \\(TR5 = TR3 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\}\\).\n\nBy applying subset semantics Rule(1):\n\n\\((\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\}) \\land (\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\}) \\land (\\{\\text{Any}\\} \\subseteq \\{\\text{Any}\\})\\)\n\n\\(< (TR5, TR4) > \\vdash True\\)\n\nTargets \\(TR4\\) and \\(TR5\\) are the same therefore \\(TR5\\) is subset or equal to \\(TR4\\).\n\n**Step 1.2.1.3.2 (R4,R5-Premise2 Evaluation)**\n\nRule R4 has two conditions defined,\n\n\\(RC4 = \\{\\text{and},\\{\\text{string-equal},\\{RAD,\\text{string},\\text{BankService/withdraw}\\}\\}\\},\\)\n\n\\(\\{\\text{string-equal},\\{SAD,\\text{subject-id},\\text{string},\\text{Joe}\\}\\}\\}\\), which means the resource must be equal to BankService/deposit and subject equal to Joe and rule R5 has 2 conditions,\n\n\\(RC5 = \\{\\text{and},\\{\\text{string-equal},\\{RAD,\\text{string},\\text{BankService/withdraw}\\}\\}\\},\\)\n\n\\(\\{\\text{string-equal},\\{SAD,\\text{subject-id},\\text{string},\\text{Joe}\\}\\}\\}\\), which means that the resource must be equal to BankService/withdraw and subject must be equal to Joe. \\(RC5\\) is equal\nto $RC4$, therefore $RC5$ is a subset or equal to $RC4$.\n\n**Step 1.2.1.3.3 (R4,R5-Premise3 Evaluation)**\n\nRule $R4$ has the opposite effect of rule $R5$. $R4,R5$ Premises 1 and 2 are satisfied, while Premise 3 is not. Applying semantics Rule (5):\n\n\\[\n\\langle TR5, TR4 \\rangle \\vdash_{\\text{subset}} \\text{True} \\land (RC5 \\subseteq RC4) \\land (RE4 \\neq RE5)\n\\]\n\n\\[\n< R4, R5 > \\rightarrow_{R.FA} \\text{null}\n\\]\n\nBased on the response from Rule (5), the returned response for $R4$ and $R5$ is null.\n\nRules $R4$ and $R5$ Analysis ends here.\n\nPolicy $P2$ Analysis ends here.\n\nFlaw Set $FS = \\{Flaw_{R3,R4}\\}$.\n\n**Step 2. (PS1-Premise2 Evaluation)**\n\nRule 8 requires the analysis of every pair of policies to determine the results of premise 2. $PS1$ has two policies $P1$ and $P2$, therefore the evaluation can continue. The evaluation of PS1-Premise2 limits our options to Rule 7.\n\n**Step 2.1. (P1,P2-Analysis)**\n\n$P1,P2$ Analysis starts here.\n\n**Step 2.1.1. (P1,P2-Premise1 Evaluation)**\n\nRule 7 premise 1 requires both $P1$ and $P2$ to have the same combining algorithms. $P1$ has $RCA = \\{\\text{deny-overrides}\\}$ and $P2$ has $RCA = \\{\\text{permit-overrides}\\}$ therefore premise\n1 of Rule (7) is not satisfied. Based on the response from Rule (7), the returned response is null.\n\n\\textit{P1,P2 Analysis ends here.}\n\n\\text{Flaw Set FS} = \\{\\text{Flaw}_{R3,R4}\\}.\n\n\\text{PS1 analysis ends here.}\n\n\\text{Flaw Set FS} = \\{\\text{Flaw}_{R3,R4}\\}.\n\nThe result from the semantics analysis for \\textit{PS1} show that \\textit{R3} and \\textit{R4} cause access flaw.\n\n\\section*{4.4.2 Redundancy Detection}\n\nIn this section, we show the redundancy analysis steps and provide the results for policy set \\textit{PS1} based on the formal analysis semantics presented in 4.2.\n\n\\textit{PolicySet PS1 redundancy analysis starts here hence our options are limited to Rule 12}\n\n\\textbf{Step 1. (PS1-Premise1 Evaluation)}\n\nRule \\textbf{12} requires the analysis of every policy individually to determine the results of premise 1. \\textit{PS1} has two policies \\textit{P1} and \\textit{P2}. Since \\textit{P1} takes a precedence order over \\textit{P2} then the analysis starts with \\textit{P1}. The evaluation of PS1-Premise1 limits our options to Rule \\textbf{10}.\n\n\\textbf{Step 1.1. (P1-Analysis)}\n\n\\textit{P1 Analysis starts here.}\nStep 1.1.1. (P1-Premise1 Evaluation)\n\nRule 10 requires analysis of rules to determine the results. P1 has two rules R1 and R2. The results of P1-premise1 depends on the evaluation of Rule 9.\n\nStep 1.1.1.1 (R1,R2-Analysis)\n\nRules R1 and R2 Analysis starts here.\n\nStep 1.1.1.1.1 (R1,R2-Premise1 Evaluation)\n\nBoth R1 and R2 have no targets defined which means\n\n\\[ TR1 = \\{ \\{ \\text{Any} \\}, \\{ \\text{Any} \\}, \\{ \\text{Any} \\} \\} \\] and \\[ TR2 = \\{ \\{ \\text{Any} \\}, \\{ \\text{Any} \\}, \\{ \\text{Any} \\} \\} \\].\n\nBy applying Intersection semantics Rule(3):\n\n\\[\n\\left( (\\{ \\text{Any} \\} \\cap \\{ \\text{Any} \\}) \\neq \\emptyset \\right) \\land \\left( (\\{ \\text{Any} \\} \\cap \\{ \\text{Any} \\}) \\neq \\emptyset \\right) \\land \\left( (\\{ \\text{Any} \\} \\cap \\{ \\text{Any} \\}) \\neq \\emptyset \\right)\n\\]\n\n\\[ \\vdash \\text{intersect True} \\]\n\nTargets TR1 and TR2 are the same therefore TR1 intersect with TR2.\n\nStep 1.1.1.1.2 (R1,R2-Premise2 Evaluation)\n\nRule R1 has 2 conditions,\n\n\\[ RC1 = \\{ \\text{and,} \\{ \\text{string-equal,} \\{ \\text{RAD,string,BankService/withdraw} \\} \\}, \\{ \\text{string-equal,} \\{ \\text{SAD,subject-id,string,Bob} \\} \\} \\} \\]\n\nwhich means that the resource must be equal to BankService/withdraw and subject must be equal to Bob and rule R2 with RC2 has no conditions defined, RC2 = {}. RC1 intersect RC2 because RC2 has no restrictions on any resources or subjects.\n\nStep 1.1.1.1.3 (R1,R2-Premise3 Evaluation)\n\nRule R1 has a permit effect and rule R2 has a deny effect, therefore premise 3 is not satisfied. Applying semantics Rule (9):\n\n93\n\\[\n(\\langle TR1, TR2 \\rangle \\models \\text{True}) \\land ((RC2 \\cap RC1) \\neq \\emptyset) \\land (RE1 \\neq RE2) \\]\n\n\\[\n\\langle R1, R2 \\rangle \\overset{\\text{null}}{\\rightarrow}_{\\text{R,RA}}\n\\]\n\nBased on the response from Rule (9), the returned response for \\( R1 \\) and \\( R2 \\) is null.\n\nRules \\( R1 \\) and \\( R2 \\) Analysis ends here.\n\nPolicy \\( P1 \\) Analysis ends here.\n\nRedundant Set \\( RS = \\emptyset \\).\n\n**Step 1.2. (P2-Analysis)**\n\n\\( P2 \\) Analysis starts here.\n\n**Step 1.2.1. (P2-Premise1 Evaluation)**\n\nRule 10 requires analysis of rules to determine the results. \\( P1 \\) has three rules \\( R3, R4 \\) and \\( R5 \\). The results of P2-premise1 depends on the evaluation of Rule 9.\n\n**Step 1.2.1.1 (R3,R4-Analysis)**\n\nRules \\( R3 \\) and \\( R4 \\) Analysis starts here.\n\n**Step 1.2.1.1.1 (R3,R4-Premise1 Evaluation)**\n\nBoth \\( R3 \\) and \\( R4 \\) have no targets defined which means\n\n\\( TR3 = \\{ \\{ \\text{Any} \\}, \\{ \\text{Any} \\}, \\{ \\text{Any} \\} \\} \\) and \\( TR4 = \\{ \\{ \\text{Any} \\}, \\{ \\text{Any} \\}, \\{ \\text{Any} \\} \\} \\).\n\nBy applying Intersection semantics Rule(3):\n\nTargets \\( TR3 \\) and \\( TR4 \\) are the same therefore \\( TR3 \\) intersect with \\( TR4 \\).\n\\[((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\text{Any}) \\neq \\emptyset)\\) < (\\text{TR3, TR4}) \\Rightarrow \\vdash \\text{intersect True}\n\n**Step 1.2.1.1.2 (R3,R4-Premise2 Evaluation)**\n\nRule R3 has one conditions defined,\n\nRC3 = \\{\\text{string-equal,\\{RAD,string,BankService/deposit\\}}\\}, which means\n\nthe resource must be equal to BankService/deposit and rule R4 has two conditions,\n\nRC4 = \\{\\text{and,\\{string-equal,\\{RAD,string,BankService/withdraw\\}\\}}, \\{\\text{string-equal,\\{SAD,subject-id,string,Joe\\}}\\}\\}, which means that the resource must\n\nbe equal to BankService/withdraw and subject must be equal to Joe. RC3 inter-\n\nsects with RC4 because both require the resource to be BankService/withdraw and\n\nRC4 limits the subject while RC3 accepts any subject.\n\n**Step 1.2.1.1.3 (R3,R4-Premise3 Evaluation)**\n\nBoth rules R3 and R4 have the same effect. All premises of Rule (9) are satisfied.\n\nApplying Rule (9):\n\n\\(< \\text{TR3, TR4} > \\vdash \\text{intersect True} \\land (\\text{RC4} \\cap \\text{RC3}) \\neq \\emptyset \\land (\\text{RE3} = \\text{RE4})\\) < R3, R4 > \\xrightarrow{R.RA} \\text{Redundant}_{R3,R4}\n\nBased on the response from Rule (9), the returned response for R3 and R4 is\n\n\\text{Redundant}_{R3,R4}.\n\nRules R3 and R4 Analysis ends here.\nRedundant Set \\( RS = \\{Redundant_{R3,R4}\\} \\).\n\n**Step 1.2.1.2** (R3,R5-Analysis)\n\nRules \\( R3 \\) and \\( R5 \\) Analysis starts here.\n\n**Step 1.2.1.2.1** (R3,R5-Premise1 Evaluation)\n\nBoth \\( R3 \\) and \\( R5 \\) have no targets defined which means\n\n\\[\nTR3 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\} \\text{ and } TR5 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\}.\n\\]\n\nBy applying the Intersection semantics Rule(3):\n\n\\[\n< (TR3, TR5) > \\vdash intersect True\n\\]\n\nTargets \\( TR3 \\) and \\( TR5 \\) are the same therefore \\( TR3 \\) intersect with \\( TR5 \\).\n\n**Step 1.2.1.2.2** (R3,R5-Premise2 Evaluation)\n\nRule \\( R3 \\) has one conditions defined,\n\n\\( RC3 = \\{\\text{string-equal},\\{\\text{RAD},\\text{string},\\text{BankService/deposit}\\}\\} \\), which means the resource must be equal to BankService/deposit and rule \\( R5 \\) has 2 conditions,\n\n\\( RC5 = \\{\\text{and},\\{\\text{string-equal},\\{\\text{RAD},\\text{string},\\text{BankService/withdraw}\\}\\}, \\{\\text{string-equal},\\{\\text{SAD},\\text{subject-id},\\text{string},\\text{Joe}\\}\\}\\} \\), which means that the resource must be equal to BankService/withdraw and subject must be equal to Joe. \\( RC3 \\) intersect with \\( RC5 \\) because both require the resource to be BankService/withdraw and \\( RC5 \\) limits the subject while \\( RC3 \\) accepts any subject.\n\n**Step 1.2.1.2.3** (R3,R5-Premise3 Evaluation)\n\nRule \\( R3 \\) has the opposite effect of rule \\( R5 \\). \\( R3,R5 \\) Premises 1 and 2 are satisfied,\nwhile Premise 3 is not. Applying semantics Rule (9):\n\n\\[\n(< TR3, TR5 > ⊬ True) ∧ ((RC3 \\cap RC5) \\neq \\emptyset) ∧ (RE3 \\neq RE5)\n\\]\n\n\\[\n< R3, R5 > \\rightarrow_{null}\n\\]\n\nBased on the response from Rule (9), the returned response for \\( R3 \\) and \\( R5 \\) is null.\n\nRules \\( R3 \\) and \\( R5 \\) Analysis ends here.\n\nRedundant Set \\( RS = \\{\\text{Redundant}_{R3, R4}\\} \\).\n\n**Step 1.2.1.3 (R4,R5-Analysis)**\n\nRules \\( R4 \\) and \\( R5 \\) Analysis starts here.\n\n**Step 1.2.1.3.1 (R4,R5-Premise1 Evaluation)**\n\nBoth \\( R4 \\) and \\( R5 \\) have no targets defined which means\n\n\\( TR4 = \\{\\{\\text{Any}\\}, \\{\\text{Any}\\}, \\{\\text{Any}\\}\\} \\) and \\( TR5 = \\{\\{\\text{Any}\\}, \\{\\text{Any}\\}, \\{\\text{Any}\\}\\} \\).\n\nBy applying the Intersection semantics Rule(3):\n\n\\[\n((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) ∧ ((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) ∧ ((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset)\n\\]\n\n\\[\n< (TR4, TR5) > \\rightarrow True\n\\]\n\nTargets \\( TR4 \\) and \\( TR5 \\) are the same therefore \\( TR5 \\) intersects with \\( TR4 \\).\n\n**Step 1.2.1.3.2 (R4,R5-Premise2 Evaluation)**\n\nRule \\( R4 \\) has two conditions defined,\nRC4 = \\{\\text{and,\\{string-equal,\\{RAD,string,BankService/withdraw\\}\\}},\n\\{\\text{string-equal,\\{SAD,subject-id,string,Joe\\}\\}}\\}, which means the\nresource must be equal to BankService/deposit and subject equal to Joe and rule\nR5 has 2 conditions, RC5 = \\{\\text{and,\\{string-equal,\\{RAD,string,BankService/withdraw\\}\\}},\n\\{\\text{string-equal,\\{SAD,subject-id,string,Joe\\}\\}}\\}, which means that the resource must\nbe equal to BankService/withdraw and subject must be equal to Joe. RC5 is equal\nto RC4, therefore RC5 intersects with RC4.\n\n**Step 1.2.1.3.3 (R4,R5-Premise3 Evaluation)**\n\nRule R4 has the opposite effect of rule R5. R4,R5 Premises 1 and 2 are satisfied,\nwhile Premise 3 is not. Applying semantics Rule (9):\n\n\\[\n\\left( < TR_4, TR_5 > \\vdash \\text{True} \\right) \\land \\left( (RC_4 \\cap RC_5) \\neq \\emptyset \\right) \\land \\left( RE_4 \\neq RE_5 \\right)\n\\]\n\n\\[\n\\frac{\\quad < R_4, R_5 > \\longrightarrow \\text{null}}{R,R_A}\n\\]\n\nBased on the response from Rule (9), the returned response for R4 and R5 is null.\n\nRules R4 and R5 Analysis ends here.\n\nPolicy P2 Analysis ends here.\n\nRedundant Set RS = \\{Redundant_{R3,R4}\\}.\n\n**Step 2. (PS1-Premise2 Evaluation)**\n\nRule 12 requires the analysis of every pair of policies to determine the results of premise\n2. PS1 has two policies P1 and P2, therefore the evaluation can continue. The evaluation\nof PS1-Premise2 limits our options to Rule 11.\nStep 2.1. (P1,P2-Analysis)\n\nP1,P2 Analysis starts here.\n\nStep 2.1.1. (P1,P2-Premise1 Evaluation)\n\nRule 11 requires both P1 and P2 to have the same combining algorithms. P1 has RCA = {deny-overrides} and P2 has RCA = {permit-overrides} therefore premise 1 of Rule (11) is not satisfied. Based on the response from Rule (11), the returned response is null.\n\nP1,P2 Analysis ends here.\n\nRedundant Set RS = \\{Redundant_{R3,R4}\\}.\n\nPS1 analysis ends here.\n\nThe results from the semantics analysis for PS1 show that R3 and R4 are redundant.\n\nRedundant Set RS = \\{Redundant_{R3,R4}\\}.\n\n4.4.3 Conflict Detection\n\nIn this section, we show the conflict analysis steps and provide the results for policy set PS1 based on the formal analysis semantics presented in 3.4.\n\nPolicySet PS1 conflict analysis starts here hence our options are limited to Rule 16\n\nStep 1. (PS1-Premise1 Evaluation)\n\nRule 16 requires the analysis of every policy individually to determine the results of premise 1. PS1 has two policies P1 and P2. Since P1 takes a precedence order over P2\nthen the analysis starts with $P1$. The evaluation of PS1-Premise1 limits our options to Rule 14.\n\n**Step 1.1. (P1-Analysis)**\n\n$P1$ Analysis starts here.\n\n**Step 1.1.1. (P1-Premise1 Evaluation)**\n\nRule 14 requires analysis of rules to determine the results. $P1$ has two rules $R1$ and $R2$. The results of $P1$-premise1 depends on the evaluation of Rule 13.\n\n**Step 1.1.1.1 (R1,R2-Analysis)**\n\nRules $R1$ and $R2$ Analysis starts here.\n\n**Step 1.1.1.1.1 (R1,R2-Premise1 Evaluation)**\n\nBoth $R1$ and $R2$ have no targets defined which means\n\n$\\text{TR1} = \\{\\text{Any},\\text{Any},\\text{Any}\\}$ and $\\text{TR2} = \\{\\text{Any},\\text{Any},\\text{Any}\\}$.\n\nBy applying Intersection semantics Rule(3):\n\n$$((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\text{Any}) \\neq \\emptyset)$$\n\n$$\\prec (\\text{TR1},\\text{TR2}) \\succ \\vdash_{\\text{intersect}} \\text{True}$$\n\nTargets $TR1$ and $TR2$ are the same therefore $TR1$ intersect with $TR2$.\n\n**Step 1.1.1.1.2 (R1,R2-Premise2 Evaluation)**\n\nRule $R1$ has 2 conditions defined,\n\n$\\text{RC1} = \\{\\text{and},\\{\\text{string-equal},\\{\\text{RAD},\\text{string},\\text{BankService/withdraw}\\}\\},$\n\n$\\{\\text{string-equal},\\{\\text{SAD},\\text{subject-id},\\text{string},\\text{Bob}\\}\\}\\}$, which means that the resource must be equal to BankService/withdraw and subject must be equal to Bob and rule $R2$\nwith $RC2$ has no conditions defined, $RC2 = \\{\\}$. $RC1$ intersect $RC2$ because $RC2$ has no restrictions on any resources or subjects.\n\n**Step 1.1.1.3 (R1,R2-Premise3 Evaluation)**\n\nRule $R1$ has a permit effect and rule $R2$ has a deny effect, therefore premise 3 is satisfied. Applying semantics Rule (13):\n\n$$\n(< TR1, TR2 > \\vdash_{intersect} True) \\land ((RC2 \\cap RC1) \\neq \\emptyset) \\land (RE1 \\neq RE2)\n$$\n\n$$\n< R1, R2 > \\xrightarrow{R,CA} Conflict_{R1,R2}\n$$\n\nBased on the response from Rule (13), the returned response for $R1$ and $R2$ is $Conflict_{R1,R2}$.\n\nRules $R1$ and $R2$ Analysis ends here.\n\nSince the analysis of Rules $R1$ and $R2$ returned $Conflict_{R1,R2}$, therefore it is added to the Conflict Set.\n\nPolicy $P1$ Analysis ends here.\n\nConflict Set $CS = \\{Conflict_{R1,R2}\\}$.\n\n**Step 1.2. (P2-Analysis)**\n\n$P2$ Analysis starts here.\n\n**Step 1.2.1. (P2-Premise1 Evaluation)**\n\nRule 14 requires analysis of rules to determine the results of premise 1. $P1$ has three\nrules $R3$, $R4$ and $R5$. The results of P2-premise1 depends on the evaluation of Rule 13.\n\n**Step 1.2.1.1 (R3,R4-Analysis)**\n\nRules $R3$ and $R4$ Analysis starts here.\n\n**Step 1.2.1.1.1 (R3,R4-Premise1 Evaluation)**\n\nBoth $R3$ and $R4$ have no targets defined which means\n\n$TR3 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\} \\text{ and } TR4 = \\{\\{\\text{Any}\\},\\{\\text{Any}\\},\\{\\text{Any}\\}\\}.$\n\nBy applying the Intersection semantics Rule(3):\n\n\\[\n((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\text{Any}) \\neq \\emptyset) < (TR3, TR4) \\vdash intersect True\n\\]\n\nTargets $TR3$ and $TR4$ are the same, therefore $TR3$ intersect with $TR4$.\n\n**Step 1.2.1.1.2 (R3,R4-Premise2 Evaluation)**\n\nRule $R3$ has one conditions defined,\n\n$RC3 = \\{\\text{string-equal},\\{\\text{RAD},\\text{string},\\text{BankService/deposit}\\}\\},$ which means\n\nthe resource must be equal to BankService/deposit and rule $R4$ has two conditions,\n\n$RC4 = \\{\\text{and},\\{\\text{string-equal},\\{\\text{RAD},\\text{string},\\text{BankService/withdraw}\\}\\},$\n\n$\\{\\text{string-equal},\\{\\text{SAD},\\text{subject-id},\\text{string},\\text{Joe}\\}\\}\\},$ which means that the resource must\n\nbe equal to BankService/withdraw and subject must be equal to Joe. $RC3$ intersects with $RC4$ because both require the resource to be BankService/withdraw and $RC4$ limits the subject while $RC3$ accepts any subject.\n\n**Step 1.2.1.1.3 (R3,R4-Premise3 Evaluation)**\n\n102\nBoth $R3$ and $R4$ have the same effect. Premises 1 and 2 are satisfied but premise 3 is not. Applying Rule (13):\n\n\\[\n< TR3, TR4 > \\vdash True \\land ((RC3 \\cap RC4) \\neq \\emptyset) \\land (RE3 = RE4)\n\\]\n\n\\[\n< R3, R4 > \\xrightarrow{R,CA} null\n\\]\n\nBased on the response from Rule (9), the returned response for $R3$ and $R4$ is null.\n\nRules $R3$ and $R4$ Analysis ends here.\n\nConflict Set $CS = \\{Conflict_{R1, R2}\\}$.\n\n**Step 1.2.1.2 (R3,R5-Analysis)**\n\nRules $R3$ and $R5$ Analysis starts here.\n\n**Step 1.2.1.2.1 (R3,R5-Premise1 Evaluation)**\n\nBoth $R3$ and $R5$ have no targets defined which means\n\n$TR3 = \\{\\{\\text{Any}\\}, \\{\\text{Any}\\}, \\{\\text{Any}\\}\\}$ and $TR5 = \\{\\{\\text{Any}\\}, \\{\\text{Any}\\}, \\{\\text{Any}\\}\\}$.\n\nBy applying the Intersection semantics Rule(3):\n\n\\[\n((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset)\n\\]\n\n\\[\n< (TR3, TR5) > \\vdash True\n\\]\n\nTargets $TR3$ and $TR5$ are the same therefore $TR3$ intersect with $TR5$.\n\n**Step 1.2.1.2.2 (R3,R5-Premise2 Evaluation)**\n\nRule $R3$ has one conditions defined,\nRC3 = \\{\\text{string-equal,\\{RAD,string,BankService/deposit\\}}\\}, which means the resource must be equal to BankService/deposit and rule R5 has 2 conditions, RC5 = \\{\\text{and,\\{string-equal,\\{RAD,string,BankService/withdraw\\}\\}}, \\{\\text{string-equal,\\{SAD,subject-id,string,Joe\\}}\\}\\}, which means that the resource must be equal to BankService/withdraw and subject must be equal to Joe. RC3 intersect with RC5 because both require the resource to be BankService/withdraw and RC5 limits the subject while RC3 accepts any subject.\n\n**Step 1.2.1.2.3 (R3,R5-Premise3 Evaluation)**\n\nRule R3 has the opposite effect of rule R5. R3,R5 Premises 1, 2 and 3 are satisfied. Applying semantics Rule (13):\n\n\\[\n\\begin{align*}\n\\langle TR_3, TR_5 \\rangle \\vdash \\text{True} & \\land (\\text{RC3} \\cap \\text{RC5}) \\neq \\emptyset \\land (\\text{RE3} \\neq \\text{RE5}) \\\\\n\\hline\n\\langle R_3, R_5 \\rangle & \\rightarrow_{R,CA} \\text{Conflict}_{R3,R5}\n\\end{align*}\n\\]\n\nBased on the response from Rule (13), the returned response for R3 and R5 is Conflict_{R3,R5}.\n\nRules R3 and R5 Analysis ends here.\n\nConflict Set CS = \\{Conflict_{R1,R2}, Conflict_{R3,R5}\\}.\n\n**Step 1.2.1.3 (R4,R5-Analysis)**\n\nRules R4 and R5 Analysis starts here.\n\n**Step 1.2.1.3.1 (R4,R5-Premise1 Evaluation)**\n\nBoth R4 and R5 have no targets defined which means\n\\( TR4 = \\{\\{\\text{Any}\\}, \\{\\text{Any}\\}, \\{\\text{Any}\\}\\} \\) and \\( TR5 = \\{\\{\\text{Any}\\}, \\{\\text{Any}\\}, \\{\\text{Any}\\}\\} \\).\n\nBy applying the Intersection semantics Rule(3):\n\n\\[\n((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset) \\land ((\\{\\text{Any}\\} \\cap \\{\\text{Any}\\}) \\neq \\emptyset)\n\\]\n\n\\[\n\\langle TR4, TR5 \\rangle \\triangleright \\text{intersect True}\n\\]\n\nTargets \\( TR4 \\) and \\( TR5 \\) are the same therefore \\( TR4 \\) intersects with \\( TR5 \\).\n\n**Step 1.2.1.3.2 (R4,R5-Premise2 Evaluation)**\n\nRule \\( R4 \\) has two conditions defined,\n\n\\( RC4 = \\{\\text{and}, \\{\\text{string-equal}, \\{\\text{RAD}, \\text{string}, \\text{BankService/withdraw}\\}\\}, \\{\\text{string-equal}, \\{\\text{SAD}, \\text{subject-id}, \\text{string}, \\text{Joe}\\}\\}\\} \\),\n\nwhich means\n\nthe resource must be equal to BankService/deposit and subject equal to Joe\n\nand rule \\( R5 \\) has 2 conditions,\n\n\\( RC5 = \\{\\text{and}, \\{\\text{string-equal}, \\{\\text{RAD}, \\text{string}, \\text{BankService/withdraw}\\}\\}, \\{\\text{string-equal}, \\{\\text{SAD}, \\text{subject-id}, \\text{string}, \\text{Joe}\\}\\}\\} \\),\n\nwhich means that\n\nthe resource must be equal to BankService/withdraw and subject must be equal to Joe. \\( RC5 \\) is equal to \\( RC4 \\), therefore \\( RC4 \\) intersects with \\( RC5 \\).\n\n**Step 1.2.1.3.3 (R4,R5-Premise3 Evaluation)**\n\nRule \\( R4 \\) has the opposite effect of rule \\( R5 \\). R4,R5 Premises 1, 2 and 3 are satisfied.\n\nApplying semantics Rule (13):\n\nBased on the response from Rule (13), the returned response for \\( R4 \\) and \\( R5 \\) is \\( Conflict_{R4,R5} \\).\n\\[(< TR4, TR5 > \\implies \\text{True}) \\land ((RC4 \\cap RC5) \\neq \\emptyset) \\land (RE4 \\neq RE5)\\]\n\n\\[< R4, R5 > \\rightarrow Conflict_{R4, R5}\\]\n\nRules \\(R4\\) and \\(R5\\) Analysis ends here.\n\nPolicy \\(P2\\) Analysis ends here.\n\nConflict Set \\(CS = \\{Conflict_{R1, R2}, Conflict_{R3, R5}, Conflict\\ R4, R5\\}\\).\n\n**Step 2. (PS1-Premise2 Evaluation)**\n\nRule \\(16\\) requires the analysis of every pair of policies to determine the results of premise 2. \\(PS1\\) has two policies \\(P1\\) and \\(P2\\), therefore the evaluation can continue. The evaluation of \\(PS1\\)-Premise2 limits our options to Rule \\(15\\).\n\n**Step 2.1. (P1,P2-Analysis)**\n\n\\(P1,P2\\) Analysis starts here.\n\n**Step 2.1.1. (P1,P2-Premise1 Evaluation)**\n\nRule \\(15\\) premise 1 requires both \\(P1\\) and \\(P2\\) to have the same combining algorithms. \\(P1\\) has \\(RCA = \\{\\text{deny-overrides}\\}\\) and \\(P2\\) has \\(RCA = \\{\\text{permit-overrides}\\}\\) therefore premise 1 of Rule \\(15\\) is not satisfied. Based on the response from Rule \\(15\\), the returned response is null.\n\n\\(P1,P2\\) Analysis ends here.\n\nConflict Set \\(CS = \\{Conflict_{R1, R2}, Conflict_{R3, R5}, Conflict\\ R4, R5\\}\\).\n\nPS1 analysis ends here.\nConflict Set \\( CS = \\{Conflict_{R1,R2}, Conflict_{R3,R5}, Conflict_{R4,R5}\\} \\).\nThe results from the semantics analysis for \\( PS1 \\) show that \\( R1 \\) conflicts with \\( R2 \\), \\( R3 \\) conflicts with \\( R5 \\) and \\( R4 \\) conflicts with \\( R5 \\).\n\n4.5 Conclusion\n\nIn this chapter, we addressed the problems related XACML policy correctness (i.e. flaw and conflict free). In the context, we proposed a model which supports the analysis of both XACML and SBA-XACML policies. It is an automatic analysis approach for detecting access flaws, conflicts and redundancies between rules and policies. In addition, we provided the semantics and its corresponding algorithms for policy analysis. We realized and demonstrate the viability of our proposition by implementing the model and developing a case study to express the effectiveness of our proposition.\nChapter Five\n\nConclusion\n\nThis thesis addressed the problems related to the efficiency of real-time decision process and correctness of XACML policies. In this context, we elaborated a novel set-based scheme called SBA-XACML, which provides efficient evaluation and analysis of XACML policies. The SBA-XACML representation of policies maintains the same XACML structure and accounts for all its elements and their sub elements including rule conditions, obligations, policy request and policy response. Moreover, the policy evaluation module, which embeds formal semantics and its implemented algorithms, takes advantage of the mathematical operations to provide efficient decision process. Unlike current literature, it holds the same architecture of the industrial standard XACML Sun PDP ([18]) and respects the major properties and assumptions of real-life environments in terms of remote policy loading upon need and disjoint reception of requests from distributed parties. The corresponding experimental results explore that SBA-XACML evaluation of large and small sizes policies has better performance than Sun PDP ([18]) and its corresponding ameliorations [12, 17, 19, 24]. Finally, the policy analysis module, which also embeds formal\nsemantics and its implemented algorithms, allows to detect access flaws, conflict and redundancy at policy and rule levels. In the sequel, we present a brief summary of the thesis contributions:\n\n- Set-Based intermediate representation of XACML constructs into readable mathematical syntax that maintain the same XACML policy structure and account for all its elements and their sub elements. The corresponding language and compiler offer automatic and optional conversion from XACML to SBA-XACML constructs.\n\n- Formal semantics and its implemented algorithms that take advantage of the mathematical operations to provide efficient policy evaluation. The presented experimental results explore that SBA-XACML evaluation of large and small sizes policies has better performance than Sun PDP [18] and its corresponding ameliorations [12, 17, 19, 24].\n\n- Formal semantics and its implemented algorithms for SBA-XACML policy analysis that enable to detect access flaws, conflicts and redundancies at both policy and rule levels.\n\n**Future Work**\n\nOur future work is to install our framework into a real world environment and monitor its performance on mixed size policies small and large and to broaden our policy analysis to detect more access control flaws, conflicts and redundancies.\nList of Publications\n\nThe following is the list of publications derived from the thesis work:\n\nConference Paper\n\n\nDraft Paper\n\n\"Towards a Set-Based Approach for Efficient Evaluation and Analysis of XACML Policies\".\nBibliography\n\n\n"}}},{"rowIdx":85,"cells":{"id":{"kind":"string","value":"7c5a2fc62c1596e969c02dddfabe8a7003c13040"},"text":{"kind":"string","value":"1 Megaco/H.248 Users Guide\n\nThe Megaco application is a framework for building applications on top of the Megaco/H.248 protocol.\n\n1.1 Introduction\n\nMegaco/H.248 is a protocol for control of elements in a physically decomposed multimedia gateway, enabling separation of call control from media conversion. A Media Gateway Controller (MGC) controls one or more Media Gateways (MG).\n\nThis version of the stack supports version 1, 2 and 3 as defined by:\n- version 1 - RFC 3525 and H.248-IG (v10-v13)\n- version 2 - draft-ietf-megaco-h248v2-04 & H.248.1 v2 Corrigendum 1 (03/2004)\n- version 3:\n - prev3a - as defined by TD-33 (except segments)\n - prev3b - TD-33 updated to be backward compatible with v2 (except segments)\n - prev3c - As defined by ITU H.248.1 (09/2005) (except segments)\n - v3 - Full version 3 as defined by ITU H.248.1 (09/2005) (including segments)\n\nThe semantics of the protocol has jointly been defined by two standardization bodies:\n- IETF - which calls the protocol Megaco\n- ITU - which calls the protocol H.248\n\n1.1.1 Scope and Purpose\n\nThis manual describes the Megaco application, as a component of the Erlang/Open Telecom Platform development environment. It is assumed that the reader is familiar with the Erlang Development Environment, which is described in a separate User’s Guide.\n\n1.1.2 Prerequisites\n\nThe following prerequisites is required for understanding the material in the Megaco User's Guide:\n- the basics of the Megaco/H.248 protocol\n- the basics of the Abstract Syntax Notation One (ASN.1)\n- familiarity with the Erlang system and Erlang programming\n\nThe application requires Erlang/OTP release R10B or later.\n\n1.1.3 About This Manual\n\nIn addition to this introductory chapter, the Megaco User's Guide contains the following chapters:\n- Chapter 2: \"Architecture\" describes the architecture and typical usage of the application.\n- Chapter 3: \"Internal form and its encodings\" describes the internal form of Megaco/H.248 messages and its various encodings.\n- Chapter 4: \"Transport mechanisms\" describes how different mechanisms can be used to transport the Megaco/H.248 messages.\n• Chapter 5: \"Debugging\" describes tracing and debugging.\n\n1.1.4 Where to Find More Information\n\nRefer to the following documentation for more information about Megaco/H.248 and about the Erlang/OTP development system:\n\n• version 1, RFC 3525\n• old version 1, RFC 3015\n• Version 2 Corrigendum 1\n• version 2, draft-ietf-megaco-h248v2-04\n• TD-33 (Draft H.248.1 version 3)\n• H.248.1 version 3\n• the ASN.1 application User's Guide\n• the Megaco application Reference Manual\n\n1.2 Architecture\n\n1.2.1 Network view\n\nMegaco is a (master/slave) protocol for control of gateway functions at the edge of the packet network. Examples of this is IP-PSTN trunking gateways and analog line gateways. The main function of Megaco is to allow gateway decomposition into a call agent (call control) part (known as Media Gateway Controller, MGC) - master, and an gateway interface part (known as Media Gateway, MG) - slave. The MG has no call control knowledge and only handle making the connections and simple configurations.\n\nSIP and H.323 are peer-to-peer protocols for call control (valid only for some of the protocols within H.323), or more generally multi-media session protocols. They both operate at a different level (call control) from Megaco in a decomposed network, and are therefor not aware of whether or not Megaco is being used underneath.\nMegaco and peer protocols are complementary in nature and entirely compatible within the same system. At a system level, Megaco allows for\n\n- overall network cost and performance optimization\n- protection of investment by isolation of changes at the call control layer\n- freedom to geographically distribute both call function and gateway function\n- adaption of legacy equipment\n\n### 1.2.2 General\n\nThis Erlang/OTP application supplies a framework for building applications that needs to utilize the Megaco/H.248 protocol.\nWe have introduced the term \"user\" as a generic term for either an MG or an MGC, since most of the functionality we support, is common for both MG's and MGC's. A (local) user may be configured in various ways and it may establish any number of connections to its counterpart, the remote user. Once a connection has been established, the connection is supervised and it may be used for the purpose of sending messages. N.B. according to the standard an MG is connected to at most one MGC, while an MGC may be connected to any number of MG's.\n\nFor the purpose of managing \"virtual MG's\", one Erlang node may host any number of MG's. In fact it may host a mix of MG's and MGC's. You may say that an Erlang node may host any number of \"users\".\n\nThe protocol engine uses callback modules to handle various things:\n\n- encoding callback modules - handles the encoding and decoding of messages. Several modules for handling different encodings are included, such as ASN.1 BER, pretty well indented text, compact text and some others. Others may be written by you.\n- transport callback modules - handles sending and receiving of messages. Transport modules for TCP/IP and UDP/IP are included and others may be written by you.\n- user callback modules - the actual implementation of an MG or MGC. Most of the functions are intended for handling of a decoded transaction (request, reply, acknowledgement), but there are others that handles connect, disconnect and errors cases.\n\nEach connection may have its own configuration of callback modules, re-send timers, transaction id ranges etc. and they may be re-configured on-the-fly.\n\nIn the API of Megaco, a user may explicitly send action requests, but generation of transaction identifiers, the encoding and actual transport of the message to the remote user is handled automatically by the protocol engine according to the actual connection configuration. Megaco messages are not exposed in the API.\n\nOn the receiving side the transport module receives the message and forwards it to the protocol engine, which decodes it and invokes user callback functions for each transaction. When a user has handled its action requests, it simply returns a list of action replies (or a message error) and the protocol engine uses the encoding module and transport module to compose and forward the message to the originating user.\n\nThe protocol stack does also handle things like automatic sending of acknowledgements, pending transactions, re-send of messages, supervision of connections etc.\n\nIn order to provide a solution for scalable implementations of MG's and MGC's, a user may be distributed over several Erlang nodes. One of the Erlang nodes is connected to the physical network interface, but messages may be sent from other nodes and the replies are automatically forwarded back to the originating node.\n\n1.2.3 Single node config\n\nHere a system configuration with an MG and MGC residing in one Erlang node each is outlined:\n1.2.4 Distributed config\n\nIn a larger system with a user (in this case an MGC) distributed over several Erlang nodes, it looks a little bit different. Here the encoding is performed on the originating Erlang node (1) and the binary is forwarded to the node (2) with the physical network interface. When the potential message reply is received on the interface on node (2), it is decoded there and then different actions will be taken for each transaction in the message. The transaction reply will be forwarded in its decoded form to the originating node (1) while the other types of transactions will be handled locally on node (2). Timers and re-send of messages will be handled on locally on one node, that is node(1), in order to avoid unnecessary transfer of data between the Erlang nodes.\n1.2.5 Message round-trip call flow\n\nThe typical round-trip of a message can be viewed as follows. Firstly we view the call flow on the originating side:\nThen we continue with the call flow on the destination side:\n1.3 Running the stack\n\n1.3.1 Starting\n\nA user may have a number of \"virtual\" connections to other users. An MG is connected to at most one MGC, while an MGC may be connected to any number of MGs. For each connection the user selects a transport service, an encoding scheme and a user callback module.\n\nAn MGC must initiate its transport service in order to listen to MGs trying to connect. How the actual transport is initiated is outside the scope of this application. However a send handle (typically a socket id or host and port) must be provided from the transport service in order to enable us to send the message to the correct destination. We do however not assume anything about this, from our point of view, opaque handle. Hopefully it is rather small since it will passed around the system between processes rather frequently.\n\nA user may either be statically configured in a .config file according to the application concept of Erlang/OTP or dynamically started with the configuration settings as arguments to megaco:start_user/2. These configuration settings may be updated later on with megaco:update_conn_info/2.\n\nThe function megaco:connect/4 is used to tell the Megaco application about which control process it should supervise, which MID the remote user has, which callback module it should use to send messages etc. When this \"virtual\" connection is established the user may use megaco:call/3 and megaco:cast/3 in order to send messages to the other\n1.3 Running the stack\n\nside. Then it is up to the MG to send its first Service Change Request message after applying some clever algorithm in order to fight the problem with startup avalanche (as discussed in the RFC).\n\nThe originating user will wait for a reply or a timeout (defined by the request_timer). When it receives the reply this will optionally be acknowledged (regulated by auto_ack), and forwarded to the user. If an interim pending reply is received, the long_request_timer will be used instead of the usual request_timer, in order to enable avoidance of spurious re-sends of the request.\n\nOn the destination side the transport service waits for messages. Each message is forwarded to the Megaco application via the megaco:receive_message/4 callback function. The transport service may or may not provide means for blocking and unblocking the reception of the incoming messages.\n\nIf a message is received before the \"virtual\" connection has been established, the connection will be setup automatically. An MGC may be real open minded and dynamically decide which encoding and transport service to use depending on how the transport layer contact is performed. For IP transports two ports are standardized, one for textual encoding and one for binary encoding. If for example an UDP packet was received on the text port it would be possible to decide encoding and transport on the fly.\n\nAfter decoding a message various user callback functions are invoked in order to allow the user to act properly. See the megaco_user module for more info about the callback arguments.\n\nWhen the user has processed a transaction request in its callback function, the Megaco application assembles a transaction reply, encodes it using the selected encoding module and sends the message back by invoking the callback function:\n\n- SendMod:send_message(SendHandle, ErlangBinary)\n\nRe-send of messages, handling pending transactions, acknowledgements etc. is handled automatically by the Megaco application but the user is free to override the default behaviour by the various configuration possibilities. See megaco:update_user_info/2 and megaco:update_conn_info/2 about the possibilities.\n\nWhen connections gets broken (that is explicitly by megaco:disconnect/2 or when its controlling process dies) a user callback function is invoked in order to allow the user to re-establish the connection. The internal state of kept messages, re-send timers etc. is not affected by this. A few re-sends will of course fail while the connection is down, but the automatic re-send algorithm does not bother about this and eventually when the connection is up and running the messages will be delivered if the timeouts are set to be long enough. The user has the option of explicitly invoking megaco:cancel/2 to cancel all messages for a connection.\n\n1.3.2 MGC startup call flow\n\nIn order to prepare the MGC for the reception of the initial message, hopefully a Service Change Request, the following needs to be done:\n\n- Start the Megaco application.\n- Start the MGC user. This may either be done explicitly with megaco:start_user/2 or implicitly by providing the -megaco users configuration parameter.\n- Initiate the transport service and provide it with a receive handle obtained from megaco:user_info/2.\n\nWhen the initial message arrives the transport service forwards it to the protocol engine which automatically sets up the connection and invokes UserMod:handle_connect/2 before it invokes UserMod:handle_trans_request/3 with the Service Change Request like this:\n1.3.3 MG startup call flow\n\nIn order to prepare the MG for the sending of the initial message, hopefully a Service Change Request, the following needs to be done:\n\n- Start the Megaco application.\n- Start the MG user. This may either be done explicitly with megaco:start_user/2 or implicitly by providing the -megaco users configuration parameter.\n- Initiate the transport service and provide it with a receive handle obtained from megaco:user_info/2.\n- Setup a connection to the MGC with megaco:connect/4 and provide it with a receive handle obtained from megaco:user_info/2.\n\nIf the MG has been provisioned with the MID of the MGC it can be given as the RemoteMid parameter to megaco:connect/4 and the call flow will look like this:\nIf the MG cannot be provisioned with the MID of the MGC, the MG can use the atom 'preliminary_mid' as the RemoteMid parameter to megaco:connect/4 and the call flow will look like this:\n1.3.4 Configuring the Megaco stack\n\nThere are three kinds of configuration:\n\n- User info - Information related to megaco users. Read/Write.\n - A User is an entity identified by a MID, e.g. a MGC or a MG.\n - This information can be retrieved using `megaco:user_info`.\n- Connection info - Information regarding connections. Read/Write.\n - This information can be retrieved using `megaco:conn_info`.\n- System info - System wide information. Read only.\n - This information can be retrieved using `megaco:system_info`.\n\n1.3.5 Initial configuration\n\nThe initial configuration of the Megaco should be defined in the Erlang system configuration file. The following configured parameters are defined for the Megaco application:\n1.3 Running the stack\n\n- users = [{Mid, [user_config()]},].\n Each user is represented by a tuple with the Mid of the user and a list of config parameters (each parameter is in turn a tuple: {Item, Value}).\n- scanner = flex | {Module, Function, Arguments, Modules}\n - flex will result in the start of the flex scanner with default options.\n - The MFA alternative makes it possible for Megaco to start and supervise a scanner written by the user (see supervisor:start_child for an explanation of the parameters).\n\nSee also Configuration of text encoding module(s) for more info.\n\n1.3.6 Changing the configuration\n\nThe configuration can be changed during runtime. This is done with the functions megaco:update_user_info and megaco:update_conn_info\n\n1.3.7 The transaction sender\n\nThe transaction sender is a process (one per connection), which handle all transaction sending, if so configured (see megaco:user_info and megaco:conn_info).\n\nThe purpose of the transaction sender is to accumulate transactions for a more efficient message sending. The transactions that are accumulated are transaction request and transaction ack. For transaction ack's the benefit is quite large, since the transactions are small and it is possible to have ranges (which means that transaction acks for transactions 1, 2, 3 and 4 can be sent as a range 1-4 in one transaction ack, instead of four separate transactions).\n\nThere are a number of configuration parameter's that control the operation of the transaction sender. In principle, a message with everything stored (ack's and request's) is sent from the process when:\n\n- When trans_timer expires.\n- When trans_ack_maxcount number of ack's has been received.\n- When trans_req_maxcount number of requests's has been received.\n- When the size of all received requests exceeds trans_req_maxsize.\n- When a reply transaction is sent.\n- When a pending transaction is sent.\n\nWhen something is to be sent, everything is packed into one message, unless the trigger was a reply transaction and the added size of the reply and all the requests is greater then trans_req_maxsize, in which case the stored transactions are sent first in a separate message and the reply in another message.\n\nWhen the transaction sender receives a request which is already “in storage” (indicated by the transaction id) it is assumed to be a resend and everything stored is sent. This could happen if the values of the trans_timer and the request_timer is not properly chosen.\n\n1.3.8 Segmentation of transaction replies\n\nIn version 3 of the megaco standard the Segmentation package was introduced. Simply, this package defines a procedure to segment megaco messages (transaction replies) when using a transport that does not automatically do this (e.g. UDP). See also version3.\n\nAlthough it would be both pointless and counterproductive to use segmentation on a transport that already does this (e.g. TCP), the megaco application does not check this. Instead, it is up to the user to configure this properly.\n\n- Receiving segmented messages:\n This is handled automatically by the megaco application. There is however one thing that need to be configured by the user, the segment_recv_timer option.\nNote that the segments are delivered to the user differently depending on which function is used to issue the original request. When issuing the request using the megaco:cast function, the segments are delivered to the user via the handle_trans_reply callback function one at a time, as they arrive. But this obviously does not work for the megaco:call function. In this case, the segments are accumulated and then delivered all at once as the function returns.\n\n- Sending segmented messages:\n \n This is also handled automatically by the megaco application. First of all, segmentation is only attempted if so configured, see the segment_send option. Secondly, megaco relies on the ability of the used codec to encode action replies, which is the smallest component the megaco application handles when segmenting. Thirdly, the reply will be segmented only if the sum of the size of the action replies (plus an arbitrary message header size) are greater than the specified max message size (see the max_pdu_size option). Finally, if segmentation is decided, then each action reply will make up its own (segment) message.\n\n1.4 Internal form and its encodings\n\nThis version of the stack is compliant with:\n\n\n1.4.1 Internal form of messages\n\nWe use the same internal form for both the binary and text encoding. Our internal form of Megaco/H.248 messages is heavily influenced by the internal format used by ASN.1 encoders/decoders:\n\n- \"SEQUENCE OF\" is represented as a list.\n- \"CHOICE\" is represented as a tagged tuple with size 2.\n- \"SEQUENCE\" is represented as a record, defined in \"megaco/include/megaco_message_v1.hrl\".\n- \"OPTIONAL\" is represented as an ordinary field in a record which defaults to ‘asn1_NOVALUE’, meaning that the field has no value.\n- \"OCTET STRING\" is represented as a list of unsigned integers.\n- \"ENUMERATED\" is represented as a single atom.\n- \"BIT STRING\" is represented as a list of atoms.\n- \"BOOLEAN\" is represented as the atom ‘true’ or ‘false’.\n- \"INTEGER\" is represented as an integer.\n- \"IA5String\" is represented as a list of integers, where each integer is the ASCII value of the corresponding character.\n- \"NULL\" is represented as the atom ‘NULL’.\n\nIn order to fully understand the internal form you must get hold on a ASN.1 specification for the Megaco/H.248 protocol, and apply the rules above. Please, see the documentation of the ASN.1 compiler in Erlang/OTP for more details of the semantics in mapping between ASN.1 and the corresponding internal form.\n\nObserve that the 'TerminationId' record is not used in the internal form. It has been replaced with a megaco_term_id record (defined in \"megaco/include/megaco.hrl\").\n1.4 Internal form and its encodings\n\n1.4.2 The different encodings\n\nThe Megaco/H.248 standard defines both a plain text encoding and a binary encoding (ASN.1 BER) and we have implemented encoders and decoders for both. We do in fact supply five different encoding/decoding modules.\n\nIn the text encoding, implementors have the choice of using a mix of short and long keywords. It is also possible to add white spaces to improve readability. We use the term compact for text messages with the shortest possible keywords and no optional white spaces, and the term pretty for a well indented text format using long keywords and an indentation style like the text examples in the Megaco/H.248 specification).\n\nHere follows an example of a text message to give a feeling of the difference between the pretty and compact versions of text messages. First the pretty, well indented version with long keywords:\n\n```\nMEGACO/1 [124.124.124.222]\nTransaction = 9998 {\n Context = - {\n ServiceChange = ROOT {\n Services {\n Method = Restart,\n ServiceChangeAddress = 55555,\n Profile = ResGW/1,\n Reason = \"901 Cold Boot\"\n }\n }\n }\n}\n```\n\nThen the compact version without indentation and with short keywords:\n\n```\n!/1 [124.124.124.222]\nT=9998{C=-{SC=R00T{SV{MT=RS,AD=55555,PF=ResGW/1,RE=\"901 Cold Boot\"}}}}\n```\n\nAnd the programmers view of the same message. First a list of ActionRequest records are constructed and then it is sent with one of the send functions in the API:\n\n```\nProf = #'ServiceChangeProfile'{profileName = \"resgw\", version = 1},\nParm = #'ServiceChangeParm'{serviceChangeMethod = restart,\n serviceChangeAddress = {portNumber, 55555},\n serviceChangeReason = \"901 Cold Boot\",\n serviceChangeProfile = Prof},\nReq = #'ServiceChangeRequest'{terminationID = ?megaco_root_termination_id},\nActions = [#'ActionRequest'{contextId = ?megaco_null_context_id,\n commandRequests = {serviceChangeReq, Req}},\nmegaco:call(ConnHandle, Actions, Config).\n```\n\nAnd finally a print-out of the entire internal form:\nThe following encoding modules are provided:\n\n- **megaco_pretty_text_encoder** - encodes messages into pretty text format, decodes both pretty as well as compact text.\n- **megaco_compact_text_encoder** - encodes messages into compact text format, decodes both pretty as well as compact text.\n- **megaco_binary_encoder** - encode/decode ASN.1 BER messages. This encoder implements the fastest of the BER encoders/decoders. Recommended binary codec.\n- **megaco_ber_encoder** - encode/decode ASN.1 BER messages.\n- **megaco_per_encoder** - encode/decode ASN.1 PER messages. N.B. that this format is not included in the Megaco standard.\n- **megaco_erl_dist_encoder** - encodes messages into Erlangs distribution format. It is rather verbose but encoding and decoding is blinding fast. N.B. that this format is not included in the Megaco standard.\n1.4.3 Configuration of Erlang distribution encoding module\n\nThe encoding_config of the megaco_erl_dist_encoder module may be one of these:\n\n- `[[]]` - Encodes the messages to the standard distribution format. It is rather verbose but encoding and decoding is blazing fast.\n- `[megaco_compressed]` - Encodes the messages to the standard distribution format after an internal transformation. It is less verbose, but the total time of the encoding and decoding will on the other hand be somewhat slower (see the performance chapter for more info).\n- `[[megaco_compressed, Module]]` - Works in the same way as the megaco_compressed config parameter, only here the user provide their own compress module. This module must implement the `megaco_edist_compress` behaviour.\n- `[compressed]` - Encodes the messages to a compressed form of the standard distribution format. It is less verbose, but the encoding and decoding will on the other hand be slower.\n\n1.4.4 Configuration of text encoding module(s)\n\nWhen using text encoding(s), there is actually two different configs controlling what software to use:\n\n- `[]` - An empty list indicates that the erlang scanner should be used.\n- `[[flex, port()]]` - Use the flex scanner when decoding (not optimized for SMP). See initial configuration for more info.\n- `[[flex, ports()]]` - Use the flex scanner when decoding (optimized for SMP). See initial configuration for more info.\n\nThe Flex scanner is a Megaco scanner written as a linked in driver (in C). There are two ways to get this working:\n\n- Let the Megaco stack start the flex scanner (load the driver).\n\n To make this happen the megaco stack has to be configured:\n \n - Add the `{scanner, flex}` (or similar) directive to an Erlang system config file for the megaco app (see initial configuration chapter for details).\n - Retrieve the encoding-config using the `system_info` function (with `Item = text_config`).\n - Update the receive handle with the encoding-config (the `encoding_config` field).\n\n The benefit of this is that Megaco handles the starting, holding and the supervision of the driver and port.\n\n- The Megaco client (user) starts the flex scanner (load the driver).\n\n When starting the flex scanner a port to the linked in driver is created. This port has to be owned by a process. This process must not die. If it does the port will also terminate. Therefor:\n\n - Create a permanent process. Make sure this process is supervised (so that if it does die, this will be noticed).\n - Let this process start the flex scanner by calling the `megaco_flex_scanner:start/0,1` function.\n - Retrieve the encoding-config and when initiating the `megaco_receive_handle`, set the field `encoding_config` accordingly.\n - Pass the `megaco_receive_handle` to the transport module.\n\n1.4.5 Configuration of binary encoding module(s)\n\nWhen using binary encoding, the structure of the termination id's needs to be specified.\n\n- `[native]` - skips the transformation phase, i.e. the decoded message(s) will not be transformed into our internal form.\n- `[integer()]` - A list containing the size (the number of bits) of each level. Example: `[3, 8, 5, 8]`. \n1.4 Internal form and its encodings\n\n- **integer()** - Number of one byte (8 bits) levels. N.B. This is currently converted into the previous config. Example: \\(3([8,8,8])\\).\n\n1.4.6 Handling megaco versions\n\nSince the version 3 implemented, in this version of the Megaco application, is preliminary, it is necessary to have a way to handle different version 3 implementations. For this reason the encoding config option \\(\\{\\text{version3, version3()}\\}\\) has been introduced. This option, if present, has to be **first** in the encoding config list. Version 1 and 2 codec's ignore this option, if found.\n\n\\[\n\\text{version3()} \\to \\text{prev3a | prev3b | prev3c | v3}\n\\]\n\n- **prev3a**\n Preliminary version 3, based on TD-33\n- **prev3b**\n Preliminary version 3, based on TD-33, but text encoding updated with the final solution for priority in \\text{contextProperty} (which is backward compatible with v2).\n- **prev3c**\n Preliminary version 3, based on the final version of the v3-standard, but **excluding** segments!\n- **v3**\n Full version 3. Including segmentation. This is the default version 3 variant (i.e. if a version 3 messages is to be encoded/decoded and no version3 encoding config is found, then v3 is assumed).\n\nThere are two ways to handle the different megaco encoding versions. Either using **dynamic version detection** (only valid for for incoming messages) or by **explicit version** setting in the connection info.\n\nFor incoming messages:\n\n- **Dynamic version detection**\n Set the protocol version in the megaco_receive_handle to \\text{dynamic} (this is the default). This works for those codecs that support partial decode of the version, currently \\text{text}, and \\text{ber_bin} (megaco_binary_encoder and megaco_ber_bin_encoder).\n This way the decoder will detect which version is used and then use the proper decoder.\n- **Explicit version**\n Explicitly set the actual protocol version in the megaco_receive_handle.\n Start with version 1. When the initial service change has been performed and version 2 has been negotiated, upgrade the megaco_receive_handle of the transport process (control_pid) to version 2. See megaco_tcp and megaco_udp.\n Note that if udp is used, the same transport process could be used for several connections. This could make upgrading impossible.\n For codecs that does not support partial decode of the version, currently megaco_ber_encoder, megaco_per_encoder and megaco_per_bin_encoder, dynamic will revert to version 1.\n\nFor outgoing messages:\n\n- **Update the connection info protocol_version.**\n- **Override protocol version when sending a message** by adding the item \\(\\{\\text{protocol_version, integer}\\}\\) to the Options. See call or cast.\n Note that this does not effect the messages that are sent autonomously by the stack. They use the protocol_version of the connection info.\n1.4.7 Encoder callback functions\n\nThe encoder callback interface is defined by the `megaco_encoder` behaviour, see `megaco_encoder`.\n\n1.5 Transport mechanisms\n\n1.5.1 Callback interface\n\nThe callback interface of the transport module contains several functions. Some of which are mandatory while others are only optional:\n\n- `send_message` - Send a message. **Mandatory**\n- `block` - Block the transport. **Optional**\n \n This function is useful for flow control.\n- `unblock` - Unblock the transport. **Optional**\n\nFor more detail, see the `megaco_transport` behaviour definition.\n\n1.5.2 Examples\n\nThe Megaco/H.248 application contains implementations for the two protocols specified by the Megaco/H.248 standard; UDP, see `megaco_udp`, and TCP/TPKT, see `megaco_tcp`.\n\n1.6 Implementation examples\n\n1.6.1 A simple Media Gateway Controller\n\nIn `megaco/examples/simple/megaco_simple_mgc.erl` there is an example of a simple MGC that listens on both text and binary standard ports and is prepared to handle a Service Change Request message to arrive either via TCP/IP or UDP/IP. Messages received on the text port are decoded using a text decoder and messages received on the binary port are decoded using a binary decoder.\n\nThe Service Change Reply is encoded in the same way as the request and sent back to the MG with the same transport mechanism UDP/IP or TCP/IP.\n\nAfter this initial service change message the connection between the MG and MGC is fully established and supervised. The MGC, with its four listeners, may be started with:\n\n```\ncd megaco/examples/simple\nerl -pa ../../../megaco/ebin -s megaco_filter -s megaco\nmegaco_simple_mgc:start().\n```\n\nor simply 'gmake mgc'.\n\nThe `-s megaco_filter` option to `erl` implies, the event tracing mechanism to be enabled and an interactive sequence chart tool to be started. This may be quite useful in order to visualize how your MGC interacts with the Megaco/H.248 protocol stack.\n\nThe event traces may alternatively be directed to a file for later analyze. By default the event tracing is disabled, but it may dynamically be enabled without any need for re-compilation of the code.\n1.6.2 A simple Media Gateway\n\nIn megaco/examples/simple/megaco_simple_mg.erl there is an example of a simple MG that connects to an MGC, sends a Service Change Request and waits synchronously for a reply.\n\nAfter this initial service change message the connection between the MG and MGC is fully established and supervised. Assuming that the MGC is started on the local host, four different MG’s, using text over TCP/IP, binary over TCP/IP, text over UDP/IP and binary over UDP/IP may be started on the same Erlang node with:\n\n```\ncd megaco/examples/simple\nerl -pa ../../../megaco/ebin -s megaco_filter -s megaco\nmegaco_simple_mg:start().\n```\nor simply 'gmake mg'.\n\nIf you \"only\" want to start a single MG which tries to connect an MG on a host named \"baidarka\", you may use one of these functions (instead of the megaco_simple_mg:start/0 above):\n\n```\nmegaco_simple_mg:start_tcp_text(\"baidarka\", []).\nmegaco_simple_mg:start_tcp_binary(\"baidarka\", []).\nmegaco_simple_mg:start_udp_text(\"baidarka\", []).\nmegaco_simple_mg:start_udp_binary(\"baidarka\", []).\n```\n\nThe -s megaco_filter option to erl implies, the event tracing mechanism to be enabled and an interactive sequence chart tool to be started. This may be quite useful in order to visualize how your MG interacts with the Megaco/H.248 protocol stack.\n\nThe event traces may alternatively be directed to a file for later analyze. By default the event tracing is disabled, but it may dynamically be enabled without any need for re-compilation of the code.\n\n1.7 Megaco mib\n\n1.7.1 Intro\n\nThe Megaco mib is as of yet not standardized and our implementation is based on draft-ietf-megaco-mib-04.txt. Almost all of the mib cannot easily be implemented by the megaco application. Instead these things should be implemented by a user (of the megaco application).\n\nSo what part of the mib is implemented? Basically the relevant statistic counters of the MedGwyGatewayStatsEntry.\n\n1.7.2 Statistics counters\n\nThe implementation of the statistic counters is lightweight. I.e. the statistic counters are handled separately by different entities of the application. For instance our two transport module(s) (see megaco_tcp and megaco_udp) maintain their own counters and the application engine (see megaco) maintain its own counters.\n\nThis also means that if a user implement their own transport service then it has to maintain its own statistics.\n\n1.7.3 Distribution\n\nEach megaco application maintains its own set of counters. So in a large (distributed) MG/MGC it could be necessary to collect the statistics from several nodes (each) running the megaco application (only one of them with the transport).\n1.8 Performance comparison\n\n1.8.1 Comparison of encoder/decoders\n\nThe Megaco/H.248 standard defines both a plain text encoding and a binary encoding (ASN.1 BER) and we have implemented encoders and decoders for both. We do supply a bunch of different encoding/decoding modules and the user may in fact implement their own (like our erl_dist module). Using a non-standard encoding format has its obvious drawbacks, but may be useful in some configurations.\n\nWe have made four different measurements of our Erlang/OTP implementation of the Megaco/H.248 protocol stack, in order to compare our different encoders/decoders. The result of each one is summarized in the table below.\n\nThe result above are the fastest of these configurations for each codec. The figures presented are the average of all used messages.\n\nFor comparison, also included are first, performance figures with megaco (including the measurement software) and asn1 applications hipe-compiled (second figure in the time columns, note that per bin decode had some issues so those figures are not included), and second, performance figures where the flex driver was built as non-reentrant flex (third figure in the time columns, only valid for text codecs using the flex-scanner, figures within parenthesis).\n\n<table>\n<thead>\n<tr>\n<th>Codec and config</th>\n<th>Size</th>\n<th>Encode</th>\n<th>Decode</th>\n<th>Total</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>pretty</td>\n<td>336</td>\n<td>20 / 13</td>\n<td>75 / 40</td>\n<td>95 / 53</td>\n</tr>\n<tr>\n<td>pretty [flex]</td>\n<td>336</td>\n<td>20 / 13 / 20</td>\n<td>39 / 33 / 38</td>\n<td>59 / 46 / 58</td>\n</tr>\n<tr>\n<td>compact</td>\n<td>181</td>\n<td>17 / 10</td>\n<td>62 / 35</td>\n<td>79 / 45</td>\n</tr>\n<tr>\n<td>compact [flex]</td>\n<td>181</td>\n<td>17 / 10 / 17</td>\n<td>37 / 31 / 36</td>\n<td>54 / 41 / 53</td>\n</tr>\n<tr>\n<td>per bin</td>\n<td>91</td>\n<td>60 / 29</td>\n<td>64 / -</td>\n<td>124 / -</td>\n</tr>\n<tr>\n<td>per bin [driver]</td>\n<td>91</td>\n<td>39 / 24</td>\n<td>42 / 26</td>\n<td>81 / 50</td>\n</tr>\n<tr>\n<td>per bin [native]</td>\n<td>91</td>\n<td>45 / 21</td>\n<td>48 / -</td>\n<td>93 / -</td>\n</tr>\n<tr>\n<td>per bin [driver,native]</td>\n<td>91</td>\n<td>25 / 15</td>\n<td>27 / 18</td>\n<td>52 / 33</td>\n</tr>\n<tr>\n<td>ber bin</td>\n<td>165</td>\n<td>32 / 19</td>\n<td>38 / 21</td>\n<td>70 / 40</td>\n</tr>\n<tr>\n<td>ber bin [driver]</td>\n<td>165</td>\n<td>32 / 19</td>\n<td>33 / 20</td>\n<td>65 / 39</td>\n</tr>\n<tr>\n<td>ber bin [native]</td>\n<td>165</td>\n<td>17 / 11</td>\n<td>25 / 13</td>\n<td>42 / 24</td>\n</tr>\n<tr>\n<td>ber bin [driver,native]</td>\n<td>165</td>\n<td>17 / 11</td>\n<td>17 / 12</td>\n<td>34 / 23</td>\n</tr>\n<tr>\n<td>erl_dist</td>\n<td>875</td>\n<td>5 / 5</td>\n<td>10 / 10</td>\n<td>15 / 15</td>\n</tr>\n<tr>\n<td>erl_dist [megaco_compressed]</td>\n<td>405</td>\n<td>6 / 4</td>\n<td>7 / 4</td>\n<td>13 / 8</td>\n</tr>\n<tr>\n<td>erl_dist [compressed]</td>\n<td>345</td>\n<td>47 / 47</td>\n<td>20 / 20</td>\n<td>67 / 67</td>\n</tr>\n</tbody>\n</table>\n1.8 Performance comparison\n\n<table>\n<thead>\n<tr>\n<th>erl_dist</th>\n<th>200</th>\n<th>34 / 33</th>\n<th>11 / 9</th>\n<th>45 / 42</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>[megaco_compressed,compressed]</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nTable 8.1: Codec performance\n\n1.8.2 System performance characteristics\n\nThis is primarily a way to show the effects of using the reentrant flex scanner instead of the non-reentrant.\n\nAs can be seen from the figures above there is no real difference between a non-reentrant and an reentrant flex scanner when it comes to the decode times of an individual message.\n\nThe real difference is instead in system characteristics, which is best shown with the mstone1 test.\n\nWhen running SMP erlang on a multi-core machine the \"throughput\" is significantly higher. The mstone1 test is an extreme test, but it shows what is gained by using the reentrant flex-scanner.\n\nFigure 8.1: MStone1 with mstone1.sh -d flex -s 4\n\n1.8.3 Description of encoders/decoders\n\nIn Appendix A of the Megaco/H.248 specification (RFC 3525), there are about 30 messages that shows a representative call flow. We have also added a few extra version 1, version 2 and version 3 messages. We have used these messages as basis for our measurements. Our figures have not been weighted in regard to how frequent the different kinds of messages that are sent between the media gateway and its controller.\n\nThe test compares the following encoder/decoders:\n\n- **pretty** - pretty printed text. In the text encoding, the protocol stack implementors have the choice of using a mix of short and long keywords. It is also possible to add white spaces to improve readability. The pretty text encoding utilizes long keywords and an indentation style like the text examples in the Megaco/H.248 specification.\n\n- **compact** - the compact text encoding uses the shortest possible keywords and no optional white spaces.\n\n- **ber** - ASN.1 BER.\n1.8 Performance comparison\n\n- **per** - ASN.1 PER. Not standardized as a valid Megaco/H.248 encoding, but included for the matter of completeness as its encoding is extremely compact.\n\n- **erl_dist** - Erlang’s native distribution format. Not standardized as a valid Megaco/H.248 encoding, but included as a reference due to its well known performance characteristics. Erlang is a dynamically typed language and any Erlang data structure may be serialized to the erl_dist format by using built-in functions.\n\nThe actual encoded messages have been collected in one directory per encoding type, containing one file per encoded message.\n\nHere follows an example of a text message to give a feeling of the difference between the pretty and compact versions of text messages. First the pretty printed, well indented version with long keywords:\n\n```\nMEGACO/1 [124.124.124.222]\n Transaction = 9998 {\n Context = - {\n ServiceChange = ROOT {\n Services {\n Method = Restart,\n ServiceChangeAddress = 55555,\n Profile = ResGW/1,\n Reason = \"901 MG Cold Boot\"\n }\n }\n }\n}\n```\n\nThen the compact text version without indentation and with short keywords:\n\n```\n!/1 [124.124.124.222] T=9998{C=-{SC=ROOT{SV{MT=RS,AD=55555,PF=ResGW/1,RE=\"901 MG Cold Boot\"}}}}\n```\n\n1.8.4 Setup\n\nThe measurements has been performed on a HP xw4600 Workstation with a Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz, with 4 GB memory and running Ubuntu 10.04 x86_64, kernel 2.6.32-22-generic. Software versions was open source OTP R13B04 (megaco-3.14).\n\n1.8.5 Summary\n\nIn our measurements we have seen that there are no significant differences in message sizes between ASN.1 BER and the compact text format. Some care should be taken when using the pretty text style (which is used in all the examples included in the protocol specification and preferred during debugging sessions) since the messages can then be quite large. If the message size really is a serious issue, our per encoder should be used, as the ASN.1 PER format is much more compact than all the other alternatives. Its major drawback is that it has not been approved as a valid Megaco/H.248 message encoding.\n\nWhen it comes to pure encode/decode performance, it turns out that:\n\n- our fastest binary encoder (ber) is about equal to our fastest text encoder (compact).\n- our fastest binary decoder (ber) is about 54% (61%) faster than our fastest text decoder (compact).\n\nIf the pure encode/decode performance really is a serious issue, our erl_dist encoder could be used, as the encoding/decoding of the erlang distribution format is much faster than all the other alternatives. Its major drawback is that it is has not been approved as a valid Megaco/H.248 message encoding.\n\nThere is no performance advantage of building (and using) a non-reentrant flex scanner over a reentrant flex scanner (if flex supports building such a scanner).\nNote:\n\nPlease, observe that these performance figures are related to our implementation in Erlang/OTP. Measurements of other implementations using other tools and techniques may of course result in other figures.\n\n1.9 Testing and tools\n\n1.9.1 Tracing\n\nWe have instrumented our code in order to enable tracing. Running the application with tracing deactivated, causes a negligible performance overhead (an external call to a function which returns an atom). Activation of tracing does not require any recompilation of the code, since we rely on Erlang/OTP's built in support for dynamic trace activation. In our case tracing of calls to a given external function.\n\nEvent traces can be viewed in a generic message sequence chart tool, e.g., or as standard output (events are written to stdio).\n\nSee `enable_trace`, `disable_trace` and `set_trace` for more info.\n\n1.9.2 Measurement and transformation\n\nWe have included some simple tool(s) for codec measurement (meas), performance tests (mstone1 and mstone2) and message transformation.\n\nThe tool(s) are located in the example/meas directory.\n\nRequirement\n\n• Erlang/OTP, version R13B01 or later.\n• Version 3.11 or later of this application.\n• Version 1.6.10 or later of the `asn1` application.\n• The flex libraries. Without it, the flex powered codecs cannot be used.\n\nMeas results\n\nThe results from the measurement run (meas) is four excel-compatible textfiles:\n\n• `decode_time.xls` -> Decoding result\n• `encode_time.xls` -> Encoding result\n• `total_time.xls` -> Total (Decoding+encoding) result\n• `message_size.xls` -> Message size\n\nInstruction\n\nThe tool contain four things:\n\n• The transformation module\n• The measurement (meas) module(s)\n• The mstone (mstone1 and mstone2) module(s)\n• The basic message file\n\nMessage Transformation\n\nThe messages used by the different tools are contained in single message package file (see below for more info). The messages in this file is encoded with just one codec. During measurement initiation, the messages are read and then transformed to all codec formats used in the measurement.\nThe message transformation is done by the transformation module. It is used to transform a set of messages encoded with one codec into the other base codec's.\n\nMeasurement(s)\n\nThere are two different measurement tools:\n\n- **meas:**\n \n Used to perform codec measurements. That is, to see what kind of performance can be expected by the different codecs provided by the megaco application.\n\n The measurement is done by iterating over the decode/encode function for approx 2 seconds per message and counting the number of decodes/encodes.\n\n Is best run by modifying the meas.sh.skel skeleton script provided by the tool.\n\n To run it manually do the following:\n\n ```\n % erl -pa <path-megaco-ebin-dir> -pa <path-to-meas-module-dir>\n Erlang (BEAM) emulator version 5.6 [source]\n Eshell V5.7.1 (abort with ^G)\n 1> megaco_codec_meas:start().\n ...\n 2> halt().\n ```\n\n or to make it even easier, assuming a measure shall be done on all the codecs (as above):\n\n ```\n % erl -noshell -pa <path-megaco-ebin-dir> -pa <path-to-meas-module-dir> -s megaco_codec_meas -s init stop\n ```\n\n When run as above (this will take some time), the measurement process is done as follows:\n\n - For each codec:\n - For each message:\n - Read the message from the file\n - Detect message version\n - Measure decode\n - Measure encode\n - Write results, encode, decode and total, to file\n\n- **mstone1 and mstone2:**\n\n These are two different SMP performance monitoring tool(s).\n\n **mstone1** creates a process for each codec config supported by the megaco application and let them run for a specific time (all at the same time), encoding and decoding megaco messages. The number of messages processed in total is the mstone1(1) value.\n\n There are different ways to run the mstone1 tool, e.g. with or without the use of drivers, with only flex-empowered configs.\n\n Is best run by modifying the mstone1.sh.skel skeleton script provided by the tool.\n\n The **mstone2** is similar to the mstone1 tool, but in this case, each created process makes only one run through the messages and then exits. A soon as a process exits, a new process (with the same config and messages) is created to takes its place. The number of messages processed in total is the mstone2(1) value.\n\n Both these tools use the message package (time_test.msgs) provided with the tool(s), although it can run on any message package as long as it has the same structure.\n**Message package file**\n\nThis is simply an erlang compatible text-file with the following structure: `{codec_name(), messages_list()`.\n\n- **codec_name()** = pretty | compact | ber | per | erlang (how the messages are encoded)\n- **messages_list()** = [{message_name(), message()}]\n- **message_name()** = atom()\n- **message()** = binary()\n\nThe codec name is the name of the codec with which all messages in the **messages_list()** has been encoded.\n\nThis file can be exported to a file structure by calling the `export_messages` function. This can be usefull if a measurement shall be done with an external tool. Exporting the messages creates a directory tree with the following structure:\n\n```\n<message package>/pretty/<message-files>\n compact/\n per/\n ber/<message-files>\n erlang/\n```\n\nThe file includes both version 1, 2 and version 3 messages.\n\n**Notes**\n\n**Binary codecs**\n\nThere are two basic ways to use the binary encodings: With package related name and termination id transformation (the 'native' encoding config) or without. This transformation converts package related names and termination id's to a more convenient internal form (equivalent with the decoded text message).\n\nThe transformation is done _after_ the actual decode has been done.\n\nFurthermore, it is possible to make use of a linked in driver that performs some of the decode/encode, decode for ber and encode for per (the 'driver' encoding config).\n\nTherefor in the tests, binary codecs are tested with four different encoding configs to determine exactly how the different options effect the performance: with transformation and without driver ([[]]), without transformation and without driver ([native]), with transformation and with driver ([driver]) and finally without transformation and with driver ([driver,native]).\n\n**Included test messages**\n\nSome of these messages are ripped from the call flow examples in an old version of the RFC and others are created to test a specific feature of megaco.\n\n**Measurement tool directory name**\n\nBe sure **not** no name the directory containing the measurement binaries starting with 'megaco-`, e.g. megaco-meas. This will confuse the erlang application loader (erlang applications are named, e.g. megaco-1.0.2).\n2 Reference Manual\n\nThe Megaco application is a framework for building applications on top of the Megaco/H.248 protocol.\nmegaco\n\nErlang module\n\nInterface module for the Megaco application\n\nDATA TYPES\n\nmegaco_mcid() = ip4Address() | ip6Address() | domainName() | deviceName() | mtpAddress()\nip4Address() = #'IP4Address'{}\nip6Address() = #'IP6Address'{}\ndomainName() = #'DomainName'{}\ndeviceName() = pathName()\npathName() = ia5String(1..64)\nmtpAddress() = octetString(2..4)\n\naction_request() = #'ActionRequest'{}\naction_reply() = #'ActionReply'{}\nerror_desc() = #'ErrorDescriptor'{}\ntransaction_reply() = #'TransactionReply'{}\nsegment_no() = integer()\n\nresend_indication() = flag | boolean()\n\nproperty_parm() = #'PropertyParm'{}\nproperty_group() = [property_parm()]\nproperty_groups() = [property_group()]\n\nsdp() = sdp_c() | sdp_o() | sdp_s() | sdp_i() | sdp_u() |\nsdp_e() | sdp_p() | sdp_b() | sdp_z() | sdp_k() |\nsdp_a() | sdp_a_rtpmap() | sdp_a_ptime() |\nsdp_t() | sdp_r() | sdp.m() |\n\nsdp_v() = #megaco_sdp_v{} (Protocol version)\nsdp_o() = #megaco_sdp_o{} (Owner/creator and session identifier)\nsdp_s() = #megaco_sdp_s{} (Session name)\nsdp_i() = #megaco_sdp_i{} (Session information)\nsdp_u() = #megaco_sdp_u{} (URI of description)\nsdp_e() = #megaco_sdp_e{} (Email address)\nsdp_p() = #megaco_sdp_p{} (Phone number)\nsdp_c() = #megaco_sdp_c{} (Connection information)\nsdp_b() = #megaco_sdp_b{} (Bandwidth information)\nsdp_k() = #megaco_sdp_k{} (Encryption key)\nsdp_a() = #megaco_sdp_a{} (Session attribute)\nsdp_a_rtpmap() = #megaco_sdp_a_rtpmap()\nsdp_a_ptime() = #megaco_sdp_a_ptime()\nsdp.a_quality() = #megaco_sdp.a_quality{}\nsdp.a_rtmp() = #megaco_sdp.a_rtmp()\nsdp.z() = #megaco_sdp.z{} (Time zone adjustment)\nsdp.t() = #megaco_sdp.t{} (Time the session is active)\nsdp.r() = #megaco_sdp.r{} (Repeat times)\nsdp.m() = #megaco_sdp.m{} (Media name and transport address)\nsdp.property_parm() = sdp() | property_parm()\nsdp.property_group() = [sdp property parm()]\nsdp.property_groups() = [sdp property groups()]\n\nmegaco.timer() = infinity | integer() >= 0 | megacoincr_timer()\nmegaco_incr_timer() = #megaco_incr_timer{}\n\nThe record megaco_incr_timer contains the following fields:\nwait_for = integer() >= 0\n The actual timer time.\nfactor = integer() >= 0\n The factor when calculating the new timer time (wait_for).\nincr = integer()\n The increment value when calculating the new timer time (wait_for). Note that this value can be negative and that a timer restart can therefor lead to a wait_for value of zero! It is up to the user to be aware of the consequences of a wait_for value of zero.\nmax_retries = infinity | infinity_restartable | integer() >= 0\n The maximum number of repetitions of the timer.\n There is a special case for this field. When the max_retries has the value infinity_restartable, it means that the timer is restartable as long as some external event occurs (e.g. receipt of a pending message for instance). But the timer will never be restarted \"by itself\", i.e. when the timer expires (whatever the timeout time), so does the timer. Whenever the timer is restarted, the timeout time will be calculated in the usual way!\n Also, as mentioned above, beware the consequences of setting the value to infinity if incr has been set to an negative value.\n\nExports\n\nstart() -> ok | {error, Reason}\nTypes:\n Reason = term()\nStarts the Megaco application\n\nUsers may either explicitly be registered with megaco:start_user/2 and/or be statically configured by setting the application environment variable 'users' to a list of {UserMid, Config} tuples. See the function megaco:start_user/2 for details.\n\nstop() -> ok | {error, Reason}\nTypes:\n Reason = term()\nStops the Megaco application\n\nstart_user(UserMid, Config) -> ok | {error, Reason}\nTypes:\n UserMid = megaco_mid()\n Config = [{user_info_item(), user_info_value()}]\n Reason = term()\nInitial configuration of a user\n\nRequires the megaco application to be started. A user is either a Media Gateway (MG) or a Media Gateway Controller (MGC). One Erlang node may host many users.\n\nA user is identified by its UserMid, which must be a legal Megaco MID.\n\nConfig is a list of {Item, Value} tuples. See megaco:user_info/2 about which items and values that are valid.\nstop_user(UserMid) -> ok | {error, Reason}\n\nTypes:\n UserMid = megaco_mid()\n Reason = term()\n\nDelete the configuration of a user\nRequires that the user does not have any active connection.\n\nuser_info(UserMid) -> [{Item, Value}]\nuser_info(UserMid, Item) -> Value | exit(Reason)\n\nTypes:\n Handle = user_info_handle()\n UserMid = megaco_mid()\n Item = user_info_item()\n Value = user_info_value()\n Reason = term()\n\nLookup user information\nThe following Item's are valid:\n\ncomm_conns\n Lists all active connections for this user. Returns a list of megaco_conn_handle records.\nreceive_handle\n Construct a megaco_receive_handle record from user config\n\ntrans_id\n Current transaction id.\n A positive integer or the atom undefined_serial (in case no messages has been sent).\nmin_trans_id\n First trans id.\n A positive integer, defaults to 1.\nmax_trans_id\n Last trans id.\n A positive integer or infinity, defaults to infinity.\n\nrequest_timer\n Wait for reply.\n The timer is cancelled when a reply is received.\n When a pending message is received, the timer is cancelled and the long_request_timer is started instead\n (see below). No resends will be performed from this point (since we now know that the other side has received\n the request).\n When the timer reaches an intermediate expire, the request is resent and the timer is restarted.\n When the timer reaches the final expire, either the function megaco:call will return with {error,\n timeout} or the callback function handle_trans_reply will be called with UserReply = {error,\n timeout} (if megaco:cast was used).\nA Megaco Timer (see explanation above), defaults to `#megaco_incr_timer()`.\n\n**long_request_timer**\n\nWait for reply after having received a pending message.\n\nWhen the timer reaches an intermediate expire, the timer is restarted.\n\nWhen a pending message is received, and the `long_request_timer` is not \"on its final leg\", the timer will be restarted, and, if `long_request_resend = true`, the request will be re-sent.\n\nA Megaco Timer (see explanation above), defaults to 60 seconds.\n\n**long_request_resend**\n\nThis option indicates whether the request should be resent until the reply is received, even though a pending message has been received.\n\nNormally, after a pending message has been received, the request is not resent (since a pending message is an indication that the request has been received). But since the reply (to the request) can be lost, this behaviour has its values.\n\nIt is of course pointless to set this value to `true` unless the `long_request_timer` (see above) is also set to an incremental timer (`#megaco_incr_timer()`).\n\nA boolean, defaults to `false`.\n\n**reply_timer**\n\nWait for an ack.\n\nWhen a request is received, some info related to the reply is stored internally (e.g. the binary of the reply). This info will live until either an ack is received or this timer expires. For instance, if the same request is received again (e.g. a request with the same transaction id), the (stored) reply will be (re-)sent automatically by megaco.\n\nIf the timer is of type `#megaco_incr_timer()`, then for each intermediate timeout, the reply will be resent (this is valid until the ack is received or the timer expires).\n\nA Megaco Timer (see explanation above), defaults to 30000.\n\n**request_keep_alive_timeout**\n\nSpecifies the timeout time for the request-keep alive timer.\n\nThis timer is started when the first reply to an asynchronous request (issued using the `megaco:cast/3` function) arrives. As long as this timer is running, replies will be delivered via the `handle_trans_reply/4,5` callback function, with their \"arrival number\" (see `UserReply` of the `handle_trans_reply/4,5` callback function).\n\nReplies arriving after the timer has expired, will be delivered using the `handle_unexpected_trans/3,4` callback function.\n\nThe timeout time can have the values: `plain` | `integer() >= 0`.\n\nDefaults to `plain`.\n\n**call_proxy_gc_timeout**\n\nTimeout time for the call proxy.\n\nWhen a request is sent using the `call/3` function, a proxy process is started to handle all replies. When the reply has been received and delivered to the user, the proxy process continues to exist for as long as this option specifies. Any received messages, is passed on to the user via the `handle_unexpected_trans` callback function.\n\nThe timeout time is in milliseconds. A value of 0 (zero) means that the proxy process will exit directly after the reply has been delivered.\n\nAn integer `>= 0`, defaults to 5000 (= 5 seconds).\nauto_ack\n Automatic send transaction ack when the transaction reply has been received (see trans_ack below).\n This is used for three-way-handshake.\n A boolean, defaults to false.\ntrans_ack\n Shall ack's be accumulated or not.\n This property is only valid if auto_ack is true.\n If auto_ack is true, then if trans_ack is false, ack's will be sent immediately. If trans_ack is true, then ack's will instead be sent to the transaction sender process for accumulation and later sending (see trans_ack_maxcount, trans_req_maxcount, trans_req_maxsize, trans_ack_maxcount and trans_timer).\n See also transaction sender for more info.\n An boolean, defaults to false.\ntrans_ack_maxcount\n Maximum number of accumulated ack's. At most this many ack's will be accumulated by the transaction sender (if started and configured to accumulate ack's).\n See also transaction sender for more info.\n An integer, defaults to 10.\ntrans_req\n Shall requests be accumulated or not.\n If trans_req is false, then request(s) will be sent immediately (in its own message).\n If trans_req is true, then request(s) will instead be sent to the transaction sender process for accumulation and later sending (see trans_ack_maxcount, trans_req_maxcount, trans_req_maxsize, trans_ack_maxcount and trans_timer).\n See also transaction sender for more info.\n An boolean, defaults to false.\ntrans_req_maxcount\n Maximum number of accumulated requests. At most this many requests will be accumulated by the transaction sender (if started and configured to accumulate requests).\n See also transaction sender for more info.\n An integer, defaults to 10.\ntrans_req_maxsize\n Maximum size of the accumulated requests. At most this much requests will be accumulated by the transaction sender (if started and configured to accumulate requests).\n See also transaction sender for more info.\n An integer, defaults to 2048.\ntrans_timer\n Transaction sender timeout time. Has two functions. First, if the value is 0, then transactions will not be accumulated (e.g. the transaction sender process will not be started). Second, if the value is greater then 0 and auto_ack and trans_ack are both true or if trans_req is true, then transaction sender will be started.\nand transactions (which is depending on the values of auto_ack, trans_ack and trans_req) will be accumulated, for later sending.\n\nSee also transaction sender for more info.\n\nAn integer, defaults to 0.\n\n**pending_timer**\n\nAutomatically send pending if the timer expires before a transaction reply has been sent. This timer is also called provisional response timer.\n\nA Megaco Timer (see explanation above), defaults to 30000.\n\n**sent_pending_limit**\n\nSent pending limit (see the MGOriginatedPendingLimit and the MGCOriginatedPendingLimit of the megaco root package). This parameter specifies how many pending messages that can be sent (for a given received transaction request). When the limit is exceeded, the transaction is aborted (see handle_trans_request_abort) and an error message is sent to the other side.\n\nNote that this has no effect on the actual sending of pending transactions. This is either implicit (e.g. when receiving a re-sent transaction request for a request which is being processed) or controlled by the pending_timer, see above.\n\nA positive integer or infinity, defaults to infinity.\n\n**recv_pending_limit**\n\nReceive pending limit (see the MGOriginatedPendingLimit and the MGCOriginatedPendingLimit of the megaco root package). This parameter specifies how many pending messages that can be received (for a sent transaction request). When the limit is exceeded, the transaction is considered lost, and an error returned to the user (through the call-back function handle_trans_reply).\n\nA positive integer or infinity, defaults to infinity.\n\n**send_mod**\n\nSend callback module which exports send_message/2. The function SendMod:send_message(SendHandle, Binary) is invoked when the bytes needs to be transmitted to the remote user.\n\nAn atom, defaults to megaco_tcp.\n\n**encoding_mod**\n\nEncoding callback module which exports encode_message/2 and decode_message/2. The function EncodingMod:encode_message(EncodingConfig, MegacoMessage) is invoked whenever a 'MegacoMessage' record needs to be translated into an Erlang binary. The function EncodingMod:decode_message(EncodingConfig, Binary) is invoked whenever an Erlang binary needs to be translated into a 'MegacoMessage' record.\n\nAn atom, defaults to megaco_pretty_text_encoder.\n\n**encoding_config**\n\nEncoding module config.\n\nA list, defaults to [].\n\n**protocol_version**\n\nActual protocol version.\n\nAn integer, default is 1.\nstrict_version\n\nStrict version control, i.e. when a message is received, verify that the version is that which was negotiated.\n\nAn boolean, default is true.\n\nreply_data\n\nDefault reply data.\n\nAny term, defaults to the atom undefined.\n\nuser_mod\n\nName of the user callback module. See the the reference manual for megaco_user for more info.\n\nuser_args\n\nList of extra arguments to the user callback functions. See the the reference manual for megaco_user for more info.\n\nthreaded\n\nIf a received message contains several transaction requests, this option indicates whether the requests should be handled sequentially in the same process (false), or if each request should be handled by its own process (true i.e. a separate process is spawned for each request).\n\nAn boolean, defaults to false.\n\nresend_indication\n\nThis option indicates weather the transport module should be told if a message send is a resend or not.\n\nIf false, megaco messages are sent using the send_message function.\n\nIf true, megaco message re-sends are made using the resend_message function. The initial message send is still done using the send_message function.\n\nThe special value flag instead indicates that the function send_message/3 shall be used.\n\nA resend_indication(), defaults to false.\n\nsegment_reply_ind\n\nThis option specifies if the user shall be notified of received segment replies or not.\n\nSee handle_segment_reply callback function for more information.\n\nA boolean, defaults to false.\n\nsegment_recv_timer\n\nThis timer is started when the segment indicated by the segmentation complete token is received, but all segments has not yet been received.\n\nWhen the timer finally expires, a \"megaco segments not received\" (459) error message is sent to the other side and the user is notified with a segment timeout UserReply in either the handle_trans_reply callback function or the return value of the call function.\n\nA Megaco Timer (see explanation above), defaults to 10000.\n\nsegment_send\n\nShall outgoing messages be segmented or not:\n\nnone\n\nDo not segment outgoing reply messages. This is useful when either it is known that messages are never to large or that the transport protocol can handle such things on its own (e.g. TCP or SCTP).\ninteger() > 0\nOutgoing reply messages will be segmented as needed (see max_pdu_size below). This value, K, indicates the outstanding window, i.e., how many segments can be outstanding (not acknowledged) at any given time.\ninfinity\nOutgoing reply messages will be segmented as needed (see max_pdu_size below). Segment messages are sent all at once (i.e., no acknowledgement awaited before sending the next segment).\nDefaults to none.\nmax_pdu_size\nMax message size. If the encoded message (PDU) exceeds this size, the message should be segmented, and then encoded.\nA positive integer or infinity, defaults to infinity.\n\nupdate_user_info(UserMid, Item, Value) -> ok | {error, Reason}\nTypes:\n UserMid = megaco_mid()\n Item = user_info_item()\n Value = user_info_value()\n Reason = term()\nUpdate information about a user\nRequires that the user is started. See megaco:user_info/2 about which items and values that are valid.\n\nconn_info(ConnHandle) -> [{Item, Value}]\nconn_info(ConnHandle, Item) -> Value | exit(Reason)\nTypes:\n ConnHandle = #megaco_conn_handle{}\n Item = conn_info_item()\n Value = conn_info_value()\n Reason = {no_such_connection, ConnHandle} | term()\nLookup information about an active connection\nRequires that the connection is active.\n\ncontrol_pid\n The process identifier of the controlling process for a connection.\nsend_handle\n Opaque send handle whose contents is internal for the send module. May be any term.\nlocal_mid\n The local mid (of the connection, i.e., the own mid). megaco_mid().\nremote_mid\n The remote mid (of the connection). megaco_mid().\nreceive_handle\n Construct a megaco_receive_handle record.\ntrans_id\n\nNext transaction id. A positive integer or the atom undefined_serial (only in case of error).\n\nNote that transaction id’s are (currently) maintained on a per user basis so there is no way to be sure that the value returned will actually be used for a transaction sent on this connection (in case a user has several connections, which is not at all unlikely).\n\nmax_trans_id\n\nLast trans id.\n\nA positive integer or infinity, defaults to infinity.\n\nrequest_timer\n\nWait for reply.\n\nThe timer is cancelled when a reply is received.\n\nWhen a pending message is received, the timer is cancelled and the long_request_timer is started instead (see below). No resends will be performed from this point (since we now know that the other side has received the request).\n\nWhen the timer reaches an intermediate expire, the request is resent and the timer is restarted.\n\nWhen the timer reaches the final expire, either the function megaco:call will return with {error, timeout} or the callback function handle_trans_reply will be called with UserReply = {error, timeout} (if megaco:cast was used).\n\nA Megaco Timer (see explanation above), defaults to #megaco_incr_timer{}.\n\nlong_request_timer\n\nWait for reply after having received a pending message.\n\nWhen the timer reaches an intermediate expire, the timer restarted.\n\nWhen a pending message is received, and the long_request_timer is not \"on its final leg\", the timer will be restarted, and, if long_request_resend = true, the request will be re-sent.\n\nA Megaco Timer (see explanation above), defaults to 60 seconds.\n\nrequest_keep_alive_timeout\n\nSpecifies the timeout time for the request-keep-alive timer.\n\nThis timer is started when the first reply to an asynchronous request (issued using the megaco:cast/3 function) arrives. As long as this timer is running, replies will be delivered via the handle_trans_reply/4,5 callback function, with their \"arrival number\" (see UserReply of the handle_trans_reply/4,5 callback function).\n\nReplies arriving after the timer has expired, will be delivered using the handle_unexpected_trans/3,4 callback function.\n\nThe timeout time can have the values: plain | integer() >= 0.\n\nDefaults to plain.\n\nlong_request_resend\n\nThis option indicates weather the request should be resent until the reply is received, even though a pending message has been received.\n\nNormally, after a pending message has been received, the request is not resent (since a pending message is an indication that the request has been received). But since the reply (to the request) can be lost, this behaviour has its values.\nIt is of course pointless to set this value to `true` unless the `long_request_timer` (see above) is also set to an incremental timer (`#megaco_incr_timer()`).\n\nA boolean, defaults to `false`.\n\n**reply_timer**\n\nWait for an ack.\n\nWhen a request is received, some info related to the reply is stored internally (e.g. the binary of the reply). This info will live until either an ack is received or this timer expires. For instance, if the same request is received again (e.g. a request with the same transaction id), the (stored) reply will be (re-)sent automatically by megaco.\n\nIf the timer is of type `#megaco_incr_timer()`, then for each intermediate timeout, the reply will be resent (this is valid until the ack is received or the timer expires).\n\nA Megaco Timer (see explanation above), defaults to 30000.\n\n**call_proxy_gc_timeout**\n\nTimeout time for the call proxy.\n\nWhen a request is sent using the `call/3` function, a proxy process is started to handle all replies. When the reply has been received and delivered to the user, the proxy process continues to exist for as long as this option specifies. Any received messages, is passed on to the user via the `handle_unexpected_trans` callback function.\n\nThe timeout time is in milliseconds. A value of 0 (zero) means that the proxy process will exit directly after the reply has been delivered.\n\nAn integer >= 0, defaults to 5000 (= 5 seconds).\n\n**auto_ack**\n\nAutomatic send transaction ack when the transaction reply has been received (see `trans_ack` below).\n\nThis is used for **three-way-handshake**.\n\nA boolean, defaults to `false`.\n\n**trans_ack**\n\nShall ack’s be accumulated or not.\n\nThis property is only valid if `auto_ack` is true.\n\nIf `auto_ack` is true, then if `trans_ack` is `false`, ack’s will be sent immediately. If `trans_ack` is `true`, then ack’s will instead be sent to the transaction sender process for accumulation and later sending (see `trans_ack_maxcount`, `trans_req_maxcount`, `trans_req_maxsize`, `trans_ack_maxcount` and `trans_timer`).\n\nSee also **transaction sender** for more info.\n\nAn boolean, defaults to `false`.\n\n**trans_ack_maxcount**\n\nMaximum number of accumulated ack’s. At most this many ack’s will be accumulated by the transaction sender (if started and configured to accumulate ack’s).\n\nSee also **transaction sender** for more info.\n\nAn integer, defaults to 10.\n\n**trans_req**\n\nShall requests be accumulated or not.\n\nIf `trans_req` is `false`, then request(s) will be sent immediately (in its own message).\nIf `trans_req` is true, then request(s) will instead be sent to the transaction sender process for accumulation and later sending (see `trans_ack_maxcount`, `trans_req_maxcount`, `trans_req_maxsize`, `trans_ack_maxcount` and `trans_timer`).\n\nSee also `transaction sender` for more info.\n\nAn `boolean`, defaults to `false`.\n\n`trans_req_maxcount`\n\n Maximum number of accumulated requests. At most this many requests will be accumulated by the transaction sender (if started and configured to accumulate requests).\n\nSee also `transaction sender` for more info.\n\nAn `integer`, defaults to `10`.\n\n`trans_req_maxsize`\n\n Maximum size of the accumulated requests. At most this much requests will be accumulated by the transaction sender (if started and configured to accumulate requests).\n\nSee also `transaction sender` for more info.\n\nAn `integer`, defaults to `2048`.\n\n`trans_timer`\n\n Transaction sender timeout time. Has two functions. First, if the value is 0, then transactions will not be accumulated (e.g. the transaction sender process will not be started). Second, if the value is greater then 0 and `auto_ack` and `trans_ack` is true or if `trans_req` is true, then transaction sender will be started and transactions (which is depending on the values of `auto_ack`, `trans_ack` and `trans_req`) will be accumulated, for later sending.\n\nSee also `transaction sender` for more info.\n\nAn `integer`, defaults to `0`.\n\n`pending_timer`\n\n Automatic send transaction pending if the timer expires before a transaction reply has been sent. This timer is also called provisional response timer.\n\nA Megaco Timer (see explanation above), defaults to `30000`.\n\n`sent_pending_limit`\n\n Sent pending limit (see the MGOterminatedPendingLimit and the MGCOriginatedPendingLimit of the megaco root package). This parameter specifies how many pending messages that can be sent (for a given received transaction request). When the limit is exceeded, the transaction is aborted (see `handle_trans_request_abort`) and an error message is sent to the other side.\n\nNote that this has no effect on the actual sending of pending transactions. This is either implicit (e.g. when receiving a re-sent transaction request for a request which is being processed) or controlled by the `pending_timer`, see above.\n\nA positive `integer` or `infinity`, defaults to `infinity`.\n\n`recv_pending_limit`\n\n Receive pending limit (see the MGOterminatedPendingLimit and the MGCOriginatedPendingLimit of the megaco root package). This parameter specifies how many pending messages that can be received (for a sent transaction request). When the limit is exceeded, the transaction is considered lost, and an error returned to the user (through the call-back function `handle_trans_reply`).\n\nA positive `integer` or `infinity`, defaults to `infinity`. \n\n---\n\nEricsson AB. All Rights Reserved.: Megaco/H.248 | 39\nsend_mod\n\nSend callback module which exports send_message/2. The function SendMod:send_message(SendHandle, Binary) is invoked when the bytes needs to be transmitted to the remote user.\n\nAn atom, defaults to megaco_tcp.\n\nencoding_mod\n\nEncoding callback module which exports encode_message/2 and decode_message/2. The function EncodingMod:encode_message(EncodingConfig, MegacoMessage) is invoked whenever a 'MegacoMessage' record needs to be translated into an Erlang binary. The function EncodingMod:decode_message(EncodingConfig, Binary) is invoked whenever an Erlang binary needs to be translated into a 'MegacoMessage' record.\n\nAn atom, defaults to megaco_pretty_text_encoder.\n\ncoding_config\n\nEncoding module config.\n\nA list, defaults to [].\n\nprotocol_version\n\nActual protocol version.\n\nAn positive integer, Current default is 1.\n\nstrict_version\n\nStrict version control, i.e. when a message is received, verify that the version is that which was negotiated.\n\nAn boolean, default is true.\n\nreply_data\n\nDefault reply data.\n\nAny term, defaults to the atom undefined.\n\nthreaded\n\nIf a received message contains several transaction requests, this option indicates whether the requests should be handled sequentially in the same process (false), or if each request should be handled by its own process (true i.e. a separate process is spawned for each request).\n\nAn boolean, defaults to false.\n\nresend_indication\n\nThis option indicates weather the transport module should be told if a message send is a resend or not.\n\nIf false, megaco messages are sent using the send_message/2 function.\n\nIf true, megaco message re-sends are made using the resend_message function. The initial message send is still done using the send_message function.\n\nThe special value flag instead indicates that the function send_message/3 shall be used.\n\nA resend_indication(), defaults to false.\n\nsegment_reply_ind\n\nThis option specifies if the user shall be notified of received segment replies or not.\n\nSee handle_segment_reply callback function for more information.\n\nA boolean, defaults to false.\nsegment_recv_timer\n\nThis timer is started when the segment indicated by the segmentation complete token (e.g. the last of the segment which makes up the reply) is received, but all segments has not yet been received.\n\nWhen the timer finally expires, a \"megaco segments not received\" (459) error message is sent to the other side and the user is notified with a segment timeout UserReply in either the handle_trans_reply callback function or the return value of the call function.\n\nA Megaco Timer (see explanation above), defaults to 10000.\n\nsegment_send\n\nShall outgoing messages be segmented or not:\n\nnone\n\nDo not segment outgoing reply messages. This is useful when either it is known that messages are never to large or that the transport protocol can handle such things on its own (e.g. TCP or SCTP).\n\ninteger() > 0\n\nOutgoing reply messages will be segmented as needed (see max_pdu_size below). This value, K, indicate the outstanding window, i.e. how many segments can be outstanding (not acknowledged) at any given time.\n\ninfinity\n\nOutgoing reply messages will be segmented as needed (see max_pdu_size below). Segment messages are sent all at once (i.e. no acknowledgement awaited before sending the next segment).\n\nDefaults to none.\n\nmax_pdu_size\n\nMax message size. If the encoded message (PDU) exceeds this size, the message should be segmented, and then encoded.\n\nA positive integer or infinity, defaults to infinity.\n\nupdate_conn_info(ConnHandle, Item, Value) -> ok | {error, Reason}\n\nTypes:\n\nConnHandle = #megaco_conn_handle{}\nItem = conn_info_item()\nValue = conn_info_value()\nReason = term()\n\nUpdate information about an active connection\n\nRequires that the connection is activated. See megaco:conn_info/2 about which items and values that are valid.\n\nsystem_info() -> [{Item, Value}] | exit(Reason)\n\nsystem_info(Item) -> Value | exit(Reason)\n\nTypes:\n\nItem = system_info_item()\n\nLookup system information\n\nThe following items are valid:\n\ntext_config\n\nThe text encoding config.\nconnections\n Lists all active connections. Returns a list of megaco_conn_handle records.\n\nusers\n Lists all active users. Returns a list of megaco_mid()'s.\n\nn_active_requests\n Returns an integer representing the number of requests that has originated from this Erlang node and still are active (and therefore consumes system resources).\n\nn_active_replies\n Returns an integer representing the number of replies that has originated from this Erlang node and still are active (and therefore consumes system resources).\n\nn_active_connections\n Returns an integer representing the number of active connections.\n\ninfo() -> Info\nTypes:\n Info = [{Key, Value}]\nThis function produces a list of information about the megaco application. Such as users and their config, connections and their config, statistics and so on.\nThis information can be produced by the functions user_info, conn_info, system_info and get_stats but this is a simple way to get it all at once.\n\nconnect(ReceiveHandle, RemoteMid, SendHandle, ControlPid) -> {ok, ConnHandle} | {error, Reason}\nconnect(ReceiveHandle, RemoteMid, SendHandle, ControlPid, Extra) -> {ok, ConnHandle} | {error, Reason}\nTypes:\n ReceiveHandle = #megaco_receive_handle{}\n RemoteMid = preliminary_mid | megaco_mid()\n SendHandle = term()\n ControlPid = pid()\n ConnHandle = #megaco_conn_handle{}\n Reason = connect_reason() | handle_connect_reason() | term()\n connect_reason() = {no_such_user, LocalMid} | {already_connected, ConnHandle} | term()\n handle_connect_error() = {connection_refused, ConnData, ErrorInfo} | term()\n LocalMid = megaco_mid()\n ConnData = term()\n ErrorInfo = term()\n Extra = term()\nEstablish a \"virtual\" connection\nActivates a connection to a remote user. When this is done the connection can be used to send messages (with SendMod:send_message/2). The ControlPid is the identifier of a process that controls the connection. That process\nwill be supervised and if it dies, this will be detected and the UserMod:handle_disconnect/2 callback function will be invoked. See the megaco_user module for more info about the callback arguments. The connection may also explicitly be deactivated by invoking megaco:disconnect/2.\n\nThe ControlPid may be the identity of a process residing on another Erlang node. This is useful when you want to distribute a user over several Erlang nodes. In such a case one of the nodes has the physical connection. When a user residing on one of the other nodes needs to send a request (with megaco:call/3 or megaco:cast/3), the message will be encoded on the originating Erlang node, and then be forwarded to the node with the physical connection. When the reply arrives, it will be forwarded back to the originator. The distributed connection may explicitly be deactivated by a local call to megaco:disconnect/2 or implicitly when the physical connection is deactivated (with megaco:disconnect/2, killing the controlling process, halting the other node, ...).\n\nThe call of this function will trigger the callback function UserMod:handle_connect/2 to be invoked. See the megaco_user module for more info about the callback arguments.\n\nA connection may be established in several ways:\n\n**provisioned MID**\n\nThe MG may explicitly invoke megaco:connect/4 and use a provisioned MID of the MGC as the RemoteMid.\n\n**upgrade preliminary MID**\n\nThe MG may explicitly invoke megaco:connect/4 with the atom 'preliminary_mid' as a temporary MID of the MGC, send an initial message, the Service Change Request, to the MGC and then wait for an initial message, the Service Change Reply. When the reply arrives, the Megaco application will pick the MID of the MGC from the message header and automatically upgrade the connection to be a \"normal\" connection. By using this method of establishing the connection, the callback function UserMod:handle_connect/2 to be invoked twice. First with a ConnHandle with the remote_mid-field set to preliminary_mid, and then when the connection upgrade is done with the remote_mid-field set to the actual MID of the MGC.\n\n**automatic**\n\nWhen the MGC receives its first message, the Service Change Request, the Megaco application will automatically establish the connection by using the MG MID found in the message header as remote mid.\n\n**distributed**\n\nWhen a user (MG/MGC) is distributed over several nodes, it is required that the node hosting the connection already has activated the connection and that it is in the \"normal\" state. The RemoteMid must be a real Megaco MID and not a preliminary_mid.\n\nAn initial megaco_receive_handle record may be obtained with megaco:user_info(UserMid, receive_handle)\n\nThe send handle is provided by the preferred transport module, e.g. megaco_tcp, megaco_udp. Read the documentation about each transport module about the details.\n\nThe connect is done in two steps: first an internal connection setup and then by calling the user handle_connect callback function. The first step could result in an error with Reason = connect_reason() and the second an error with Reason = handle_connect_reason():\n\n```erlang\nconnect_reason()\n```\n\nAn error with this reason is generated by the megaco application itself.\n\n```erlang\nhandle_connect_reason()\n```\n\nAn error with this reason is caused by the user handle_connect callback function either returning an error or an invalid value.\n\nExtra can be any term() except the atom ignore_extra. It is passed (back) to the user via the callback function handle_connect/3.\ndisconnect(ConnHandle, DiscoReason) -> ok | {error, ErrReason}\n\nTypes:\n ConnHandle = conn_handle()\n DiscoReason = term()\n ErrReason = term()\n\nTear down a \"virtual\" connection\nCauses the UserMod:handle_disconnect/2 callback function to be invoked. See the megaco_user module for more info about the callback arguments.\n\ncall(ConnHandle, Actions, Options) -> {ProtocolVersion, UserReply}\n\nTypes:\n ConnHandle = conn_handle()\n Actions = action_reqs() | [action_reqs()]\n action_reqs() = binary() | [action_request()]\n Options = [send_option()]\n send_option() = [request_timer, megaco_timer()] | [long_request_timer, megaco_timer()] | [send_handle, term()] | [protocol_version, integer()] | [call_proxy_gc_timeout, call_proxy_gc_timeout()]\n ProtocolVersion = integer()\n UserReply = user_reply() | [user_reply()]\n user_reply() = success() | failure()\n success() = {ok, result()} | {ok, result(), extra()}\n result() = message_result() | segment_result()\n message_result() = action_reps()\n segment_result() = segments_ok()\n failure() = {error, reason()} | {error, reason(), extra()}\n reason() = message_reason() | segment_reason() | user_cancel_reason() | send_reason() | other_reason()\n message_reason() = error_desc()\n segment_reason() = {segment, segments_ok(), segments_err()} | {segment_timeout, missing_segments(), segments_ok(), segments_err()}\n segments_ok() = [segment_ok()]\n segment_ok() = {segment_no(), action_reps()}\n segments_err() = [segment_err()]\n segment_err() = {segment_no(), error_desc()}\n missing_segments() = [segment_no()]\n user_cancel_reason() = {user_cancel, reason_for_user_cancel()}\n reason_for_user_cancel() = term()\n send_reason() = send_cancelled_reason() | send_failed_reason()\n send_cancelled_reason() = {send_message_cancelled, reason_for_send_cancel()}\n reason_for_send_cancel() = term()\n send_failed_reason() = {send_message_failed, reason_for_send_failure()}\n reason_for_send_failure() = term()\nother_reason() = \\{wrong_mid, WrongMid, RightMid, TR\\} | term()\nWrongMid = mid()\nRightMid = mid()\nTR = transaction_reply()\naction_reps() = \\[action_reply()\\]\ncall_proxy_gc_timeout() = integer() >= 0\nextra() = term()\n\nSends one or more transaction request(s) and waits for the reply.\n\nWhen sending one transaction in a message, Actions should be action_reqs() (UserReply will then be user_reply()). When sending several transactions in a message, Actions should be \\[action_reqs()\\] (UserReply will then be \\[user_reply()\\]). Each element of the list is part of one transaction.\n\nFor some of our codecs (not binary), it is also possible to pre-encode the actions, in which case Actions will be either a binary() or \\[binary()\\].\n\nThe function returns when the reply arrives, when the request timer eventually times out or when the outstanding requests are explicitly cancelled.\n\nThe default values of the send options are obtained by megaco:conn_info(ConnHandle, Item). But the send options above, may explicitly be overridden.\n\nThe ProtocolVersion version is the version actually encoded in the reply message.\n\nAt success(), the UserReply contains a list of 'ActionReply' records possibly containing error indications.\n\nA message_error(), indicates that the remote user has replied with an explicit transactionError.\nA user_cancel_error(), indicates that the request has been canceled by the user. reason_for_user_cancel() is the reason given in the call to the cancel function.\nA send_error(), indicates that the send function of the megaco transport callback module failed to send the request. There are two separate cases: send_cancelled_reason() and send_failed_reason(). The first is the result of the send function returning \\{cancel, Reason\\} and the second is some other kind of erroneous return value. See the send_message function for more info.\nAn other_error(), indicates some other error such as timeout.\nFor more info about the extra() part of the result, see the note in the user callback module documentation.\n\ncast(ConnHandle, Actions, Options) -> ok | \\{error, Reason\\}\nTypes:\n ConnHandle = conn_handle()\n Actions = action_reqs() | \\[action_reqs()\\]\n action_reqs() = binary() | \\[action_request()\\]\n Options = \\{send_option()\\}\n send_option() = \\{request_keep_alive_timeout, request_keep_alive_timeout()\\}\n | \\{request_timer, megaco_timer()\\} | \\{long_request_timer, megaco_timer()\\}\n | \\{send_handle, term()\\} | \\{reply_data, reply_data()\\} | \\{protocol_version, integer()\\}\n request_keep_alive_timeout() = plain | integer() >= 0\n Reason = term()\n\nSends one or more transaction request(s) but does NOT wait for a reply\nWhen sending one transaction in a message, Actions should be action_reqs(). When sending several transactions in a message, Actions should be [action_reqs()]. Each element of the list is part of one transaction.\n\nFor some of our codecs (not binary), it is also possible to pre-encode the actions, in which case Actions will be either a binary() or [binary()].\n\nThe default values of the send options are obtained by megaco:conn_info(ConnHandle, Item). But the send options above, may explicitly be overridden.\n\nThe ProtocolVersion version is the version actually encoded in the reply message.\n\nThe callback function UserMod:handle_trans_reply/4 is invoked when the reply arrives, when the request timer eventually times out or when the outstanding requests are explicitly cancelled. See the megaco_user module for more info about the callback arguments.\n\nGiven as UserData argument to UserMod:handle_trans_reply/4.\n\n```\nencode_actions(ConnHandle, Actions, Options) -> {ok, BinOrBins} | {error, Reason}\n```\n\nTypes:\n- ConnHandle = conn_handle()\n- Actions = action_reqs() | [action_reqs()]\n- action_reqs() = [#'ActionRequest'{}\n- Options = [send_option()]\n- send_option() = {request_timer, megaco_timer()} | {long_request_timer, megaco_timer()} | {send_handle, term()} | {protocol_version, integer()}\n- BinOrBins = binary() | [binary()]\n- Reason = term()\n\nEncodes lists of action requests for one or more transaction request(s).\n\nWhen encoding action requests for one transaction, Actions should be action_reqs(). When encoding action requests for several transactions, Actions should be [action_reqs()]. Each element of the list is part of one transaction.\n\n```\ntoken_tag2string(Tag) -> Result\ntoken_tag2string(Tag, EncoderMod) -> Result\ntoken_tag2string(Tag, EncoderMod, Version) -> Result\n```\n\nTypes:\n- Tag = atom()\n- EncoderMod = pretty | compact | encoder_module()\n- encoder_module() = megaco_pretty_text_encoder | megaco_compact_text_encoder | atom()\n- Version = int_version() | atom_version()\n- int_version() = 1 | 2 | 3\n- atom_version() = v1 | v2 | v3 | prev3c | prev3b\n- Result = string() | {error, Reason}\n- Reason = term()\n\nConvert a token tag to a string\n\nIf no encoder module is given, the default is used (which is pretty).\nIf no or an unknown version is given, the **best** version is used (which is v3). If no match is found for `Tag`, `Result` will be the empty string (`[]`).\n\n```erlang\ncancel(ConnHandle, CancelReason) -> ok | {error, ErrReason}\n```\n\n**Types:**\n- `ConnHandle = conn_handle()`\n- `CancelReason = term()`\n- `ErrReason = term()`\n\nCancel all outstanding messages for this connection\n\nThis causes outstanding megaco:call/3 requests to return. The callback functions `UserMod:handle_reply/4` and `UserMod:handle_trans_ack/4` are also invoked where it applies. See the `megaco_user` module for more info about the callback arguments.\n\n```erlang\nprocess_received_message(ReceiveHandle, ControlPid, SendHandle, BinMsg) -> ok\n```\n\n**Types:**\n- `ReceiveHandle = #megaco_receive_handle{}`\n- `ControlPid = pid()`\n- `SendHandle = term()`\n- `BinMsg = binary()`\n- `Extra = term()`\n\nProcess a received message\n\nThis function is intended to be invoked by some transport modules when get an incoming message. Which transport that actually is used is up to the user to choose.\n\nThe message is delivered as an Erlang binary and is decoded by the encoding module stated in the receive handle together with its encoding config (also in the receive handle). Depending of the outcome of the decoding various callback functions will be invoked. See `megaco_user` for more info about the callback arguments.\n\nThe argument `Extra` is just an opaque data structure passed to the user via the callback functions in the `user callback module`. Note however that if `Extra` has the value `extra_undefined` the argument will be ignored (same as if `process_received_message/4` had been called). See the documentation for the behaviour of the callback module, `megaco_user`, for more info.\n\nNote that all processing is done in the context of the calling process. A transport module could call this function via one of the `spawn` functions (e.g. `spawn_opt`). See also `receive_message/4,5`.\n\nIf the message cannot be decoded the following callback function will be invoked:\n- `UserMod:handle_syntax_error/3`\n\nIf the decoded message instead of transactions contains a message error, the following callback function will be invoked:\n- `UserMod:handle_message_error/3`\n\nIf the decoded message happens to be received before the connection is established, a new “virtual” connection is established. This is typically the case for the Media Gateway Controller (MGC) upon the first Service Change. When this occurs the following callback function will be invoked:\n- `UserMod:handle_connect/2`\nFor each transaction request in the decoded message the following callback function will be invoked:\n\n- UserMod:handle_trans_request/3\n\nFor each transaction reply in the decoded message the reply is returned to the user. Either the originating function megaco:call/3 will return. Or in case the originating function was megaco:case/3 the following callback function will be invoked:\n\n- UserMod:handle_trans_reply/4\n\nWhen a transaction acknowledgement is received it is possible that user has decided not to bother about the acknowledgement. But in case the return value from UserMod:handle_trans_request/3 indicates that the acknowledgement is important the following callback function will be invoked:\n\n- UserMod:handle_trans_ack/4\n\nSee the megaco_user module for more info about the callback arguments.\n\nreceive_message(ReceiveHandle, ControlPid, SendHandle, BinMsg) -> ok\nreceive_message(ReceiveHandle, ControlPid, SendHandle, BinMsg, Extra) -> ok\n\nTypes:\n- ReceiveHandle = #megaco_receive_handle{}\n- ControlPid = pid()\n- SendHandle = term()\n- BinMsg = binary()\n- Extra = term()\n\nProcess a received message\n\nThis is a callback function intended to be invoked by some transport modules when get an incoming message. Which transport that actually is used is up to the user to choose.\n\nIn principle, this function calls the process_received_message/4 function via a spawns to perform the actual processing.\n\nFor further information see the process_received_message/4 function.\n\nparse_digit_map(DigitMapBody) -> {ok, ParsedDigitMap} | {error, Reason}\n\nTypes:\n- DigitMapBody = string()\n- ParsedDigitMap = parsed_digit_map()\n- parsed_digit_map() = term()\n- Reason = term()\n\nParses a digit map body\n\nParses a digit map body, represented as a list of characters, into a list of state transitions suited to be evaluated by megaco:eval_digit_map/1,2.\n\neval_digit_map(DigitMap) -> {ok, MatchResult} | {error, Reason}\neval_digit_map(DigitMap, Timers) -> {ok, MatchResult} | {error, Reason}\n\nTypes:\n- DigitMap = '#DigitMapValue'{} | parsed_digit_map()\n- parsed_digit_map() = term()\n- ParsedDigitMap = term()\nCollect digit map letters according to the digit map.\n\nWhen evaluating a digit map, a state machine waits for timeouts and letters reported by megaco:report_digit_event/2. The length of the various timeouts are defined in the digit_map_value() record.\n\nWhen a complete sequence of valid events has been received, the result is returned as a list of letters.\n\nThere are two options for handling syntax errors (that is when an unexpected event is received when the digit map evaluator is expecting some other event). The unexpected events may either be ignored or rejected. The latter means that the evaluation is aborted and an error is returned.\n\nreport_digit_event(DigitMapEvalPid, Events) -> ok | {error, Reason}\n\nTypes:\n\nDigitMapEvalPid = pid()\nEvents = Event | [Event]\nEvent = letter() | pause() | cancel()\nletter() = $0..$9 | $a .. $k\npause() = one_second() | ten_seconds()\none_second() = $s | $S\nten_seconds() = $l | $L\ncancel() = $z | $Z | cancel\nReason = term()\n\nSend one or more events to the event collector process.\n\nSend one or more events to a process that is evaluating a digit map, that is a process that is executing megaco:eval_digit_map/1,2.\n\nNote that the events $s | $S, $l and $z | $Z has nothing to do with the timers using the same characters.\n\ntest_digit_event(DigitMap, Events) -> {ok, Kind, Letters} | {error, Reason}\n\nTypes:\n\nDigitMap = #'DigitMapValue'{} | parsed_digit_map()\nparsed_digit_map() = term()\nParsedDigitMap = term()\nTimers = ignore() | reject()\nignore() = ignore | (ignore, digit_map_value())\nreject() = reject | (reject, digit_map_value()) | digit_map_value()\nDigitMapEvalPid = pid()\nEvents = Event | [Event]\nEvent = letter() | pause() | cancel()\nKind = kind()\nkind() = full | unambiguous\nLetters = [letter()]\nletter() = $0..$9 | $a .. $k | $A .. $K\npause() = one_second() | ten_seconds()\none_second() = $s | $S\nten_seconds() = $L | $L\ncancel () = $z | $Z | cancel\nReason = term()\n\nFeed digit map collector with events and return the result\nThis function starts the evaluation of a digit map with megaco:eval_digit_map/1 and sends a sequence of events to it\nmegaco:report_digit_event/2 in order to simplify testing of digit maps.\n\nencode_sdp(SDP) -> {ok, PP} | {error, Reason}\n\nTypes:\nSDP = sdp_property_parm() | sdp_property_group() | sdp_property_groups() |\nasn1_NOVALUE\nPP = property_parm() | property_group() | property_groups() | asn1_NOVALUE\nReason = term()\n\nEncode (generate) an SDP construct.\nIf a property_parm() is found as part of the input (SDP) then it is left unchanged.\nThis function performs the following transformation:\n• sdp() -> property_parm()\n• sdp_property_group() -> property_group()\n• sdp_property_groups() -> property_groups()\n\ndecode_sdp(PP) -> {ok, SDP} | {error, Reason}\n\nTypes:\nPP = property_parm() | property_group() | property_groups() | asn1_NOVALUE\nSDP = sdp() | decode_sdp_property_group() | decode_sdp_property_groups() |\nasn1_NOVALUE\ndecode_sdp() = sdp() | (property_parm(), DecodeError)\ndecode_sdp_property_group() = [decode_sdp()]\ndecode_sdp_property_groups() = [decode_sdp_property_group()]\nDecodeError = term()\nReason = term()\n\nDecode (parse) a property parameter construct.\nWhen decoding property_group() or property_groups(), those property parameter constructs that cannot\nbe decoded (either because of decode error or because they are unknown), will be returned as a two-tuple. The first\nelement of which will be the (undecoded) property parameter and the other the actual reason. This means that the caller\nof this function has to expect not only sdp-records, but also this two-tuple construct.\nThis function performs the following transformation:\n\n- property_parm() -> sdp()\n- property_group() -> sdp_property_group()\n- property_groups() -> sdp_property_groups()\n\n`versions1()` -> `{ok, VersionInfo} | {error, Reason}\n`versions2()` -> `{ok, Info} | {error, Reason}\n\nTypes:\n\n- `VersionInfo = [version_info()]`\n- `version_info() = term()`\n- `Reason = term()`\n\nUtility functions used to retrieve some system and application info.\n\nThe difference between the two functions is in how they get the modules to check. `versions1` uses the app-file and `versions2` uses the function `application:get_key`.\n\n`print_version_info()` -> `void()`\n`print_version_info(VersionInfo)` -> `void()\n\nTypes:\n\n- `VersionInfo = [version_info()]`\n- `version_info() = term()`\n\nUtility function to produce a formatted printout of the versions info generated by the `versions1` and `versions2` functions.\n\nThe function `print_version_info/0` uses the result of function `versions1/0` as `VersionInfo`.\n\nExample:\n\n```\n{ok, V} = megaco:versions1(), megaco:format_versions(V).\n```\n\n`enable_trace(Level, Destination)` -> `void()`\n\nTypes:\n\n- `Level = max | min | 0 <= integer() = 100`\n- `Destination = File | Port | HandlerSpec | io`\n- `File = string()`\n- `Port = integer()`\n- `HandlerSpec = {HandlerFun, Data}`\n- `HandleFun = fun() (two arguments)`\n- `Data = term()`\n\nThis function is used to start megaco tracing at a given Level and direct result to the given Destination.\n\nIt starts a tracer server and then sets the proper match spec (according to Level).\n\nIn the case when Destination is File, the printable megaco trace events will be printed to the file File using plain io:format/2.\n\nIn the case when Destination is io, the printable megaco trace events will be printed on stdout using plain io:format/2.\nSee dbg for further information.\n\n**disable_trace() -> void()**\n\nThis function is used to stop megaco tracing.\n\n**set_trace(Level) -> void()**\n\nTypes:\n\n```\nLevel = max | min | 0 <= integer() <= 100\n```\n\nThis function is used to change the megaco trace level.\n\nIt is assumed that tracing has already been enabled (see `enable_trace` above).\n\n**get_stats() -> {ok, TotalStats} | {error, Reason}**\n\n**get_stats(GlobalCounter) -> {ok, CounterStats} | {error, Reason}**\n\n**get_stats(ConnHandle) -> {ok, ConnHandleStats} | {error, Reason}**\n\n**get_stats(ConnHandle, Counter) -> {ok, integer()} | {error, Reason}**\n\nTypes:\n\n```\nTotalStats = [total_stats()]\ntotal_stats() = {conn_handle(), [stats()]} | {global_counter(), integer()}\nGlobalCounter = global_counter()\nGlobalCounterStats = integer()\nConnHandle = conn_handle()\nConnHandleStats = [stats()]\nstats() = {counter(), integer()}\nCounter = counter()\ncounter() = medGwyGatewayNumTimerRecovery | medGwyGatewayNumErrors\nglobal_counter() = medGwyGatewayNumErrors\nReason = term()\n```\n\nRetrieve the (SNMP) statistic counters maintained by the megaco application. The global counters handle events that cannot be attributed to a single connection (e.g. protocol errors that occur before the connection has been properly setup).\n\n**reset_stats() -> void()**\n\n**reset_stats(ConnHandle) -> void()**\n\nTypes:\n\n```\nConnHandle = conn_handle()\n```\n\nReset all related (SNMP) statistics counters.\n\n**test_request(ConnHandle, Version, EncodingMod, EncodingConfig, Actions) -> {MegaMsg, EncodeRes}**\n\nTypes:\n\n```\nConnHandle = conn_handle()\nVersion = integer()\nEncodingMod = atom()\n```\nEncodingConfig = Encoding configuration\nActions = A list\nMegaMsg = #'MegacoMessage'{}\nEncodeRes = {ok, Bin} | {error, Reason}\nBin = binary()\nReason = term()\n\nTests if the Actions argument is correctly composed.\nThis function is only intended for testing purposes. It's supposed to have a same kind of interface as the call or cast\nfunctions (with the additions of the EncodingMod and EncodingConfig arguments). It composes a complete\nmegaco message end attempts to encode it. The return value, will be a tuple of the composed megaco message and\nthe encode result.\n\ntest_reply(ConnHandle, Version, EncodingMod, EncodingConfig, Reply) ->\n{MegaMsg, EncodeRes}\nTypes:\n ConnHandle = conn_handle()\n Version = integer()\n EncodingMod = atom()\n EncodingConfig = A list\n Reply = actual_reply()\n MegaMsg = #'MegacoMessage'{}\n EncodeRes = {ok, Bin} | {error, Reason}\n Bin = binary()\n Reason = term()\n\nTests if the Reply argument is correctly composed.\nThis function is only intended for testing purposes. It's supposed to test the actual_reply() return value of\nthe callback functions handle_trans_request and handle_trans_long_request functions (with the additions of the\nEncodingMod and EncodingConfig arguments). It composes a complete megaco message end attempts to\nencode it. The return value, will be a tuple of the composed megaco message and the encode result.\nThe following functions should be exported from a `megaco_edist_compress` callback module:\n\n### Exports\n\n**Module:encode(R, Version) -> T**\n\nTypes:\n\n\\[\nR = \\text{megaco_encoder:megaco_message() | megaco_encoder:transaction()}\n\\]\n\n\\[\n| \\text{megaco_encoder:action_reply() | megaco_encoder:action_request() | megaco_encoder:command_request()}\n\\]\n\n\\[\n\\text{Version} = \\text{megaco_encoder:protocol_version()}\n\\]\n\n\\[\nT = \\text{term()}\n\\]\n\nCompress a megaco component. The erlang dist encoder makes no assumption on the how or even if the component is compressed.\n\n**Module:decode(T, Version) -> R**\n\nTypes:\n\n\\[\nT = \\text{term()}\n\\]\n\n\\[\n\\text{Version} = \\text{megaco_encoder:protocol_version()}\n\\]\n\n\\[\nR = \\text{megaco_encoder:megaco_message() | megaco_encoder:transaction()}\n\\]\n\n\\[\n| \\text{megaco_encoder:action_reply() | megaco_encoder:action_request() | megaco_encoder:command_request()}\n\\]\n\nDecompress a megaco component.\nmegaco_encoder\n\nErlang module\n\nThe following functions should be exported from a megaco_encoder callback module:\n\n**DATA TYPES**\n\nNote:\n\nNote that the actual definition of (some of) these records depend on the megaco protocol version used. For instance, the 'TransactionReply' record has two more fields in version 3, so a simple erlang type definition cannot be made here.\n\n```erlang\nprotocol_version() = integer() \nsegment_no() = integer() \nmegaco_message() = #'MegacoMessage{}'\ntransaction() = {transactionRequest, transaction_request()} |\n{transactionPending, transaction_reply()} |\n{transactionReply, transaction_pending()} |\n{transactionResponseAck, transaction_response_ack()} |\n{segmentReply, segment_reply()}\ntransaction_request() = #'TransactionRequest{}'\ntransaction_pending() = #'TransactionPending{}'\ntransaction_reply() = #'TransactionReply{}'\ntransaction_response_ack() = [transaction_ack()]\ntransaction_ack() = #'TransactionAck{}'\nsegment_reply() = #'SegmentReply{}'\naction_request() = #'ActionRequest{}'\naction_reply() = #'ActionReply{}'\ncommand_request() = #'CommandRequest{}'\nerror_desc() = #'ErrorDescriptor{}'\n```\n\nExports\n\nModule:encode_message(EncodingConfig, Version, Message) -> {ok, Bin} | Error\nTypes:\n\n- EncodingConfig = list()\n- Version = integer()\n- Message = megaco_message()\n- Bin = binary()\n- Error = term()\n\nEncode a megaco message.\n\nModule:decode_message(EncodingConfig, Version, Bin) -> {ok, Message} | Error\nTypes:\n\n- EncodingConfig = list()\n- Version = integer() | dynamic\n- Message = megaco_message()\n- Bin = binary()\nDecode a megaco message. Note that if the Version argument is dynamic, the decoder should try to figure out the actual version from the message itself and then use the proper decoder, e.g. version 1. If on the other hand the Version argument is an integer, it means that this is the expected version of the message and the decoder for that version should be used.\n\nModule:decode_mini_message(EncodingConfig, Version, Bin) -> {ok, Message} | Error\nTypes:\n\n EncodingConfig = list()\n Version = integer() | dynamic\n Message = megaco_message()\n Bin = binary()\n Error = term()\n\nPerform a minimal decode of a megaco message. The purpose of this function is to do a minimal decode of Megaco message. A successful result is a 'MegacoMessage' in which only version and mid has been initiated. This function is used by the megaco_messenger module when the decode_message/3 function fails to figure out the mid (the actual sender) of the message.\n\nNote again that a successful decode only returns a partially initiated message.\n\nModule:encode_transaction(EncodingConfig, Version, Transaction) -> OK | Error\nTypes:\n\n EncodingConfig = list()\n Version = integer()\n Transaction = transaction()\n OK = {ok, Bin}\n Bin = binary()\n Error = {error, Reason}\n Reason = not_implemented | OtherReason\n OtherReason = term()\n\nEncode a megaco transaction. If this, for whatever reason, is not supported, the function should return the error reason not_implemented.\n\nThis functionality is used both when the transaction sender is used and for segmentation. So, for either of those to work, this function must be fully supported!\n\nModule:encode_action_requests(EncodingConfig, Version, ARs) -> OK | Error\nTypes:\n\n EncodingConfig = list()\n Version = integer()\n ARs = action_requests()\n action_requests() = [action_request()]\n OK = {ok, Bin}\nEncode megaco action requests. This function is called when the user calls the function `encode_actions/3`. If that function is never used or if the codec cannot support this (the encoding of individual actions), then return with error reason `not_implemented`.\n\nModule:encode_action_reply(EncodingConfig, Version, AR) -> OK | Error\n\nTypes:\n\n- EncodingConfig = list()\n- Version = integer()\n- AR = action_reply()\n- OK = {ok, Bin}\n- Bin = binary()\n- Error = {error, Reason}\n- Reason = notImplemented | OtherReason\n- OtherReason = term()\n\nEncode a megaco action reply. If this, for whatever reason, is not supported, the function should return the error reason `not_implemented`.\n\nThis function is used when segmentation has been configured. So, for this to work, this function must be fully supported!\nThe following functions should be exported from a \\texttt{megaco\\_transport} callback module:\n\n- \\texttt{send\\_message/2} [mandatory]\n- \\texttt{send\\_message/3} [optional]\n- \\texttt{resend\\_message/2} [optional]\n\n\\section*{Exports}\n\n\\begin{Verbatim}\nModule:send\\_message(Handle, \\texttt{Msg}) \\rightarrow \\texttt{ok} | \\{\\texttt{cancel}, \\texttt{Reason}\\} | \\texttt{Error}\nModule:send\\_message(Handle, \\texttt{Msg}, \\texttt{Resend}) \\rightarrow \\texttt{ok} | \\{\\texttt{cancel}, \\texttt{Reason}\\} | \\texttt{Error}\n\\end{Verbatim}\n\n\\textbf{Types:}\n\n\\begin{itemize}\n \\item \\texttt{Handle} = \\texttt{term()}\n \\item \\texttt{Msg} = \\texttt{binary()} \\mid \\texttt{iolist()}\n \\item \\texttt{Resend} = \\texttt{boolean()}\n \\item \\texttt{Reason} = \\texttt{term()}\n \\item \\texttt{Error} = \\texttt{term()}\n\\end{itemize}\n\nSend a megaco message.\n\nIf the function returns \\{\\texttt{cancel}, \\texttt{Reason}\\}, this means the transport module decided not to send the message. This is \\textbf{not} an error. No error messages will be issued and no error counters incremented. What actions this will result in depends on what kind of message was sent.\n\nIn the case of requests, megaco will cancel the message in much the same way as if \\texttt{megaco:cancel} had been called (after a successfull send). The information will be propagated back to the user differently depending on how the request(s) where issued: For requests issued using \\texttt{megaco:call}, the info will be delivered in the return value. For requests issued using \\texttt{megaco:cast} the info will be delivered via a call to the callback function \\texttt{handle\\_trans\\_reply}.\n\nIn the case of reply, megaco will cancel the reply and information of this will be returned to the user via a call to the callback function \\texttt{handle\\_trans\\_ack}.\n\nThe function \\texttt{send\\_message/3} will only be called if the \\texttt{resend\\_indication} config option has been set to the value \\texttt{false}. The third argument, \\texttt{Resend} then indicates if the message send is a resend or not.\n\n\\begin{Verbatim}\nModule:resend\\_message(Handle, \\texttt{Msg}) \\rightarrow \\texttt{ok} | \\{\\texttt{cancel}, \\texttt{Reason}\\} | \\texttt{Error}\n\\end{Verbatim}\n\n\\textbf{Types:}\n\n\\begin{itemize}\n \\item \\texttt{Handle} = \\texttt{term()}\n \\item \\texttt{Msg} = \\texttt{binary()} \\mid \\texttt{iolist()}\n \\item \\texttt{Reason} = \\texttt{term()}\n \\item \\texttt{Error} = \\texttt{term()}\n\\end{itemize}\n\nRe-send a megaco message.\n\nNote that this function will only be called if the user has set the \\texttt{resend\\_indication} config option to \\texttt{trueand} it is in fact a message resend. If not \\textbf{both} of these condition's are meet, \\texttt{send\\_message} will be called.\nIf the function returns `(cancel, Reason)`, this means the transport module decided not to send the message. This is **not** an error. No error messages will be issued and no error counters incremented. What actions this will result in depends on what kind of message was sent.\n\nIn the case of requests, megaco will cancel the message in much the same way as if `megaco:cancel` had been called (after a successful send). The information will be propagated back to the user differently depending on how the request(s) were issued: For requests issued using `megaco:call`, the info will be delivered in the return value. For requests issued using `megaco:cast` the info will be delivered via a call to the callback function `handle_trans_reply`.\n\nIn the case of reply, megaco will cancel the reply and information of this will be returned to the user via a call to the callback function `handle_trans_ack`.\nmegaco_tcp\n\nErlang module\n\nThis module contains the public interface to the TPKT (TCP/IP) version transport protocol for Megaco/H.248.\n\nExports\n\nstart_transport() -> {ok, TransportRef}\nTypes:\n TransportRef = pid()\nThis function is used for starting the TCP/IP transport service. Use exit(TransportRef, Reason) to stop the transport service.\n\nlisten(TransportRef, ListenPortSpecList) -> ok\nTypes:\n TransportRef = pid() | regname()\n OptionListPerPort = [Option]\n Option = {port, integer()} | {options, list()} | {receive_handle, term()}\nThis function is used for starting new TPKT listening socket for TCP/IP. The option list contains the socket definitions.\n\nconnect(TransportRef, OptionList) -> {ok, Handle, ControlPid} | {error, Reason}\nTypes:\n TransportRef = pid() | regname()\n OptionList = [Option]\n Option = {host, Ipaddr} | {port, integer()} | {options, list()} | {receive_handle, term()} | {module, atom()}\n Handle = socket_handle()\n ControlPid = pid()\n Reason = term()\nThis function is used to open a TPKT connection.\n\nThe module option makes it possible for the user to provide their own callback module. The receive_message/4 or process_received_message/4 functions of this module is called when a new message is received (which one depends on the size of the message: small - receive_message, large - process_received_message). Default value is megaco.\n\nclose(Handle) -> ok\nTypes:\n Handle = socket_handle()\nThis function is used for closing an active TPKT connection.\n\nsocket(Handle) -> Socket\nTypes:\n```erlang\nHandle = socket_handle()\nSocket = inet_socket()\n\nThis function is used to convert a socket_handle() to a inet_socket(). inet_socket() is a plain socket, see the inet module for more info.\n\nsend_message(Handle, Message) -> ok\nTypes:\n Handle = socket_handle()\n Message = binary() | iolist()\n\nSends a message on a connection.\n\nblock(Handle) -> ok\nTypes:\n Handle = socket_handle()\n\nStop receiving incoming messages on the socket.\n\nunblock(Handle) -> ok\nTypes:\n Handle = socket_handle()\n\nStarting to receive incoming messages from the socket again.\n\nupgrade_receive_handle(ControlPid) -> ok\nTypes:\n ControlPid = pid()\n\nUpdate the receive handle of the control process (e.g. after having changed protocol version).\n\nget_stats() -> {ok, TotalStats} | {error, Reason}\nget_stats(SendHandle) -> {ok, SendHandleStats} | {error, Reason}\nget_stats(SendHandle, Counter) -> {ok, CounterStats} | {error, Reason}\nTypes:\n TotalStats = [send_handle_stats()]\n total_stats() = [send_handle(), [stats()]]\n SendHandle = send_handle()\n SendHandleStats = [stats()]\n Counter = tcp_stats_counter()\n CounterStats = integer()\n stats() = [tcp_stats_counter(), integer()]\n tcp_stats_counter() = medGwyGatewayNumInMessages | medGwyGatewayNumInOctets | medGwyGatewayNumOutMessages | medGwyGatewayNumOutOctets | medGwyGatewayNumErrors\n Reason = term()\n\nRetreive the TCP related (SNMP) statistics counters.\n```\nreset_stats() -> void()\nreset_stats(SendHandle) -> void()\n\nTypes:\n\nSendHandle = send_handle()\n\nReset all TCP related (SNMP) statistics counters.\nThis module contains the public interface to the UDP/IP version transport protocol for Megaco/H.248.\n\nExports\n\nstart_transport() -> {ok, TransportRef}\nTypes:\n TransportRef = pid()\nThis function is used for starting the UDP/IP transport service. Use exit(TransportRef, Reason) to stop the transport service.\n\nopen(TransportRef, OptionList) -> {ok, Handle, ControlPid} | {error, Reason}\nTypes:\n TransportRef = pid() | regname()\n OptionList = [option()]\n option() = {port, integer()} | {options, list()} | {receive_handle, receive_handle()} | {module, atom()}\n Handle = socket_handle()\n receive_handle() = term()\n ControlPid = pid()\n Reason = term()\nThis function is used to open an UDP/IP socket.\n\nThe module option makes it possible for the user to provide their own callback module. The functions receive_message/4 or process_received_message/4 of this module is called when a new message is received (which one depends on the size of the message; small - receive_message, large - process_received_message). Default value is megaco.\n\nclose(Handle, Msg) -> ok\nTypes:\n Handle = socket_handle()\n Msg\nThis function is used for closing an active UDP socket.\n\nsocket(Handle) -> Socket\nTypes:\n Handle = socket_handle()\n Socket = inet_socket()\nThis function is used to convert a socket_handle() to a inet_socket(). inet_socket() is a plain socket, see the inet module for more info.\ncreate_send_handle(Handle, Host, Port) -> send_handle()\nTypes:\n Handle = socket_handle()\n Host = {A,B,C,D} | string()\n Port = integer()\nCreates a send handle from a transport handle. The send handle is intended to be used by megaco_udp:send_message/2.\n\nsend_message(SendHandle, Msg) -> ok\nTypes:\n SendHandle = send_handle()\n Message = binary() | iolist()\nSends a message on a socket. The send handle is obtained by megaco_udp:create_send_handle/3. Increments the NumOutMessages and NumOutOctets counters if message successfully sent. In case of a failure to send, the NumErrors counter is not incremented. This is done elsewhere in the megaco app.\n\nblock(Handle) -> ok\nTypes:\n Handle = socket_handle()\nStop receiving incoming messages on the socket.\n\nunblock(Handle) -> ok\nTypes:\n Handle = socket_handle()\nStarting to receive incoming messages from the socket again.\n\nupgrade_receive_handle(ControlPid, NewHandle) -> ok\nTypes:\n ControlPid = pid()\n NewHandle = receive_handle()\n receive_handle() = term()\nUpdate the receive handle of the control process (e.g. after having changed protocol version).\n\nget_stats() -> {ok, TotalStats} | {error, Reason}\nget_stats(SendHandle) -> {ok, SendHandleStats} | {error, Reason}\nget_stats(SendHandle, Counter) -> {ok, CounterStats} | {error, Reason}\nTypes:\n TotalStats = [total_stats()]\n total_stats() = {send_handle(), [stats()]}\n SendHandle = send_handle()\n SendHandleStats = [stats()]\n Counter = udp_stats_counter()\n CounterStats = integer()\n stats() = {udp_stats_counter(), integer()}\n\n64 | Ericsson AB. All Rights Reserved.: Megaco/H.248\ntcp_stats_counter() = medGwyGatewayNumInMessages | medGwyGatewayNumInOctets | medGwyGatewayNumOutMessages | medGwyGatewayNumOutOctets | medGwyGatewayNumErrors\n\nReason = term()\n\nRetrieve the UDP related (SNMP) statistics counters.\n\nreset_stats() -> void()\nreset_stats(SendHandle) -> void()\n\nTypes:\n SendHandle = send_handle()\n\nReset all TCP related (SNMP) statistics counters.\nThis module defines the callback behaviour of Megaco users. A megaco_user compliant callback module must export the following functions:\n\n- handle_connect/2,3\n- handle_disconnect/3\n- handle_syntax_error/3,4\n- handle_message_error/3,4\n- handle_trans_request/3,4\n- handle_trans_long_request/3,4\n- handle_trans_reply/4,5\n- handle_trans_ack/4,5\n- handle_unexpected_trans/3,4\n- handle_trans_request_abort/4,5\n- handle_segment_reply/5,6\n\nThe semantics of them and their exact signatures are explained below.\n\nThe user_args configuration parameter which may be used to extend the argument list of the callback functions. For example, the handle_connect function takes by default two arguments:\n\n```\nhandle_connect(Handle, Version)\n```\n\nbut if the user_args parameter is set to a longer list, such as [SomePid, SomeTableRef], the callback function is expected to have these (in this case two) extra arguments last in the argument list:\n\n```\nhandle_connect(Handle, Version, SomePid, SomeTableRef)\n```\n\n**Note:**\n\nMost of the functions below has an optional Extra argument (e.g. handle_unexpected_trans/4). The functions which takes this argument will be called if and only if one of the functions receive_message/5 or process_received_message/5 was called with the Extra argument different than ignore_extra.\n\n**DATA TYPES**\n\n- action_request() = #'ActionRequest'{}\n- action_reply() = #'ActionReply'{}\n- error_desc() = #'ErrorDescriptor'{}\n- segment_no() = integer()\n\n- conn_handle() = #megaco_conn_handle{}\n\nThe record initially returned by megaco:connect/4,5. It identifies a \"virtual\" connection and may be reused after a reconnect (disconnect + connect).\n\n- protocol_version() = integer()\n\nIs the actual protocol version. In most cases the protocol version is retrieved from the processed message, but there are exceptions:\n• When `handle_connect/2,3` is triggered by an explicit call to `megaco:connect/4,5`.\n• `handle_disconnect/3`\n• `handle_syntax_error/3`\n\nIn these cases, the `ProtocolVersion` default version is obtained from the static connection configuration:\n\n• `megaco:conn_info(ConnHandle, protocol_version)`.\n\nExports\n\n`handle_connect(ConnHandle, ProtocolVersion) -> ok | error | {error, ErrorDescr}`\n`handle_connect(ConnHandle, ProtocolVersion, Extra) -> ok | error | {error, ErrorDescr}`\n\nTypes:\n\n- `ConnHandle = conn_handle()`\n- `ProtocolVersion = protocol_version()`\n- `ErrorDescr = error_desc()`\n- `Extra = term()`\n\nInvoked when a new connection is established.\n\nConnections may either be established by an explicit call to `megaco:connect/4` or implicitly at the first invocation of `megaco:receive_message/3`.\n\nNormally a Media Gateway (MG) connects explicitly while a Media Gateway Controller (MGC) connects implicitly.\n\nAt the Media Gateway Controller (MGC) side it is possible to reject a connection request (and send a message error reply to the gateway) by returning `{error, ErrorDescr}` or simply `error` which generates an error descriptor with code 402 (unauthorized) and reason \"Connection refused by user\" (this is also the case for all unknown results, such as exit signals or throw).\n\nSee note above about the `Extra` argument in `handle_message_error/4`.\n\n`handle_connect/3` (with `Extra`) can also be called as a result of a call to the `megaco:connect/5` function (if that function is called with the `Extra` argument different than `ignore_extra`.\n\n`handle_disconnect(ConnHandle, ProtocolVersion, Reason) -> ok`\n\nTypes:\n\n- `ConnHandle = conn_handle()`\n- `ProtocolVersion = protocol_version()`\n- `Reason = term()`\n\nInvoked when a connection is teared down.\n\nThe disconnect may either be made explicitly by a call to `megaco:disconnect/2` or implicitly when the control process of the connection dies.\n\n`handle_syntax_error(ReceiveHandle, ProtocolVersion, DefaultED) -> reply | {reply, ED} | no_reply | {no_reply, ED}`\n`handle_syntax_error(ReceiveHandle, ProtocolVersion, DefaultED, Extra) -> reply | {reply, ED} | no_reply | {no_reply, ED}`\n\nTypes:\nReceiveHandle = receive_handle()\nProtocolVersion = protocol_version()\nDefaultED = error_desc()\nED = error_desc()\nExtra = term()\n\nInvoked when a received message had syntax errors\n\nIncoming messages is delivered by megaco:receive_message/4 and normally decoded successfully. But if the decoding failed this function is called in order to decide if the originator should get a reply message (reply) or if the reply silently should be discarded (no_reply).\n\nSyntax errors are detected locally on this side of the protocol and may have many causes, e.g. a malfunctioning transport layer, wrong encoder/decoder selected, bad configuration of the selected encoder/decoder etc.\n\nThe error descriptor defaults to DefaultED, but can be overridden with an alternate one by returning \\{reply,ED\\} or \\{no_reply,ED\\} instead of reply and no_reply respectively.\n\nAny other return values (including exit signals or throw) and the DefaultED will be used.\n\nSee note above about the Extra argument in handle_syntax_error/4.\n\nhandle_message_error(ConnHandle, ProtocolVersion, ErrorDescr) -> ok\nhandle_message_error(ConnHandle, ProtocolVersion, ErrorDescr, Extra) -> ok\n\nTypes:\n ConnHandle = conn_handle()\n ProtocolVersion = protocol_version()\n ErrorDescr = error_desc()\n Extra = term()\n\nInvoked when a received message just contains an error instead of a list of transactions.\n\nIncoming messages is delivered by megaco:receive_message/4 and successfully decoded. Normally a message contains a list of transactions, but it may instead contain an ErrorDescriptor on top level of the message.\n\nMessage errors are detected remotely on the other side of the protocol. And you probably don't want to reply to it, but it may indicate that you have outstanding transactions that not will get any response (request -> reply; reply -> ack).\n\nSee note above about the Extra argument in handle_message_error/4.\n\nhandle_trans_request(ConnHandle, ProtocolVersion, ActionRequests) ->\npending() | reply() | ignore_trans_request\nhandle_trans_request(ConnHandle, ProtocolVersion, ActionRequests, Extra) ->\npending() | reply() | ignore_trans_request\n\nTypes:\n ConnHandle = conn_handle()\n ProtocolVersion = protocol_version()\n ActionRequests = \\[action_request()\\]\n Extra = term()\n pending() = \\{pending, req_data()\\}\n req_data() = term()\n reply() = \\{ack_action(), actual_reply()\\} | \\{ack_action(), actual_reply(), send_options()\\}\nack_action() = discard_ack | {handle_ack, ack_data()} | {handle_pending_ack, ack_data()} | {handle_sloppy_ack, ack_data()}\nactual_reply() = [action_reply()] | error_desc()\nack_data() = term()\nsend_options() = [send_option()]\nsend_option() = {reply_timer, megaco_timer()} | {send_handle, term()} | {protocol_version, integer()}\nExtra = term()\n\nInvoked for each transaction request\n\nIncoming messages is delivered by megaco:receive_message/4 and successfully decoded. Normally a message contains a list of transactions and this function is invoked for each TransactionRequest in the message.\n\nThis function takes a list of 'ActionRequest' records and has three main options:\nReturn ignore_trans_request\n\nDecide that these action requests shall be ignored completely.\n\nReturn pending()\n\nDecide that the processing of these action requests will take a long time and that the originator should get an immediate 'TransactionPending' reply as interim response. The actual processing of these action requests instead should be delegated to the the handle_trans_long_request/3 callback function with the req_data() as one of its arguments.\n\nReturn reply()\n\nProcess the action requests and either return an error_descr() indicating some fatal error or a list of action replies (wildcarded or not).\n\nIf for some reason megaco is unable to deliver the reply, the reason for this will be passed to the user via a call to the callback function handle_trans_ack, unless ack_action() = discard_ack.\n\nThe ack_action() is either:\ndiscard_ack\n\nMeaning that you don’t care if the reply is acknowledged or not.\n\n{handle_ack, ack_data()} | {handle_ack, ack_data(), send_options()}\n\nMeaning that you want an immediate acknowledgement when the other part receives this transaction reply. When the acknowledgement eventually is received, the handle_trans_ack/4 callback function will be invoked with the ack_data() as one of its arguments. ack_data() may be any Erlang term.\n\n{handle_pending_ack, ack_data()} | {handle_pending_ack, ack_data(), send_options()}\n\nThis has the same effect as the above, if and only if megaco has sent at least one pending message for this request (during the processing of the request). If no pending message has been sent, then immediate acknowledgement will not be requested.\n\nNote that this only works as specified if the sent_pending_limit config option has been set to an integer value.\n\n{handle_sloppy_ack, ack_data()} | {handle_sloppy_ack, ack_data(), send_options()}\n\nMeaning that you want an acknowledgement sometime. When the acknowledgement eventually is received, the handle_trans_ack/4 callback function will be invoked with the ack_data() as one of its arguments. ack_data() may be any Erlang term.\nAny other return values (including exit signals or throw) will result in an error descriptor with code 500 (internal gateway error) and the module name (of the callback module) as reason.\n\nSee note above about the Extra argument in handle_trans_request/4.\n\nhandle_trans_long_request(ConnHandle, ProtocolVersion, ReqData) -> reply()\nhandle_trans_long_request(ConnHandle, ProtocolVersion, ReqData, Extra) -> reply()\n\nTypes:\nConnHandle = conn_handle()\nProtocolVersion = protocol_version()\nReqData = req_data()\nExtra = term()\n\nreq_data() = term()\nreply() = {ack_action(), actual_reply()} | {ack_action(), actual_reply(),\nsend_options()}\nack_action() = discard_ack | {handle_ack, ack_data()} |\n{handle_sloppy_ack, ack_data()}\nactual_reply() = [action_reply()] | error_desc()\nack_data() = term()\nsend_options() = [send_option()]\nsend_option() = {reply_timer, megaco_timer()} | {send_handle, term()} |\n{protocol_version, integer()}\n\nExtra = term()\n\nOptionally invoked for a time consuming transaction request\n\nIf this function gets invoked or not is controlled by the reply from the preceding call to handle_trans_request/3. The handle_trans_request/3 function may decide to process the action requests itself or to delegate the processing to this function.\n\nThe req_data() argument to this function is the Erlang term returned by handle_trans_request/3.\n\nAny other return values (including exit signals or throw) will result in an error descriptor with code 500 (internal gateway error) and the module name (of the callback module) as reason.\n\nSee note above about the Extra argument in handle_trans_long_request/4.\n\nhandle_trans_reply(ConnHandle, ProtocolVersion, UserReply, ReplyData) -> ok\nhandle_trans_reply(ConnHandle, ProtocolVersion, UserReply, ReplyData, Extra) -> ok\n\nTypes:\nConnHandle = conn_handle()\nProtocolVersion = protocol_version()\nUserReply = success() | failure()\nsuccess() = {ok, result()}\nresult() = transaction_result() | segment_result()\ntransaction_result() = action_reps()\nsegment_result() = {segment_no(), last_segment(), action_reps()}\naction_reps() = [action_reply()]\nfailure() = {error, reason()} | {error, ReplyNo, reason()}\nreason() = transaction_reason() | segment_reason() | user_cancel_reason()\n| send_reason() | other_reason()\ntransaction_reason() = error_desc()\nsegment_reason() = {segment_no(), last_segment(), error_desc()}\nother_reason() = timeout | {segment_timeout, missing_segments()} |\nexceeded_recv_pending_limit | term()\nlast_segment() = bool()\nmissing_segments() = [segment_no()]\nuser_cancel_reason() = {user_cancel, reason_for_user_cancel()}\nreason_for_user_cancel() = term()\nsend_reason() = send_cancelled_reason() | send_failed_reason()\nsend_cancelled_reason() = {send_message_cancelled,\nreason_for_send_cancel()}\nreason_for_send_cancel() = term()\nsend_failed_reason() = {send_message_failed, reason_for_send_failure()}\nreason_for_send_failure() = term()\nReplyData = reply_data()\nReplyNo = integer() > 0\nreply_data() = term()\nExtra = term()\n\nOptionally invoked for a transaction reply\n\nThe sender of a transaction request has the option of deciding, whether the originating Erlang process\nshould synchronously wait (megaco:call/3) for a reply or if the message should be sent asynchronously\n(megaco:cast/3) and the processing of the reply should be delegated this callback function.\n\nNote that if the reply is segmented (split into several smaller messages; segments), then some extra info, segment\nnumber and an indication if all segments of a reply has been received or not, is also included in the UserReply.\n\nThe ReplyData defaults to megaco:lookup(ConnHandle, reply_data), but may be explicitly overridden\nby a megaco:cast/3 option in order to forward info about the calling context of the originating process.\n\nAt success(), the UserReply either contains:\n• A list of 'ActionReply' records possibly containing error indications.\n• A tuple of size three containing: the segment number, the last segment indicator and finally a list\nof 'ActionReply' records possibly containing error indications. This is of course only possible if the reply was\nsegmented.\n\nfailure() indicates an local or external error and can be one of the following:\n• A transaction_reason(), indicates that the remote user has replied with an explicit transactionError.\n• A segment_reason(), indicates that the remote user has replied with an explicit transactionError for this\nsegment. This is of course only possible if the reply was segmented.\n• A user_cancel_reason(), indicates that the request has been canceled by the user.\n reason_for_user_cancel() is the reason given in the call to the cancel function.\n• A send_reason(), indicates that the transport module send_message function did not send the message. The\n reason for this can be:\n• send_cancelled_reason() - the message sending was deliberately cancelled. reason_for_send_cancel() is the reason given in the cancel return from the send_message function.\n• send_failed_reason() - an error occurred while attempting to send the message.\n• An other_reason(), indicates some other error such as:\n • timeout - the reply failed to arrive before the request timer expired.\n • {segment_timeout, missing_segments()} - one or more segments was not delivered before the expire of the segment timer.\n • exceeded_recv_pending_limit - the pending limit was exceeded for this request.\n\nSee note above about the Extra argument in handle_trans_reply/5.\n\nhandle_trans_ack(ConnHandle, ProtocolVersion, AckStatus, AckData) -> ok\nhandle_trans_ack(ConnHandle, ProtocolVersion, AckStatus, AckData, Extra) -> ok\n\nTypes:\n ConnHandle = conn_handle()\n ProtocolVersion = protocol_version()\n AckStatus = ok | {error, reason()}\n reason() = user_cancel_reason() | send_reason() | other_reason()\n user_cancel_reason() = {user_cancel, reason_for_user_cancel()}\n send_reason() = send_cancelled_reason() | send_failed_reason()\n send_cancelled_reason() = {send_message_cancelled, reason_for_send_cancel()}\n reason_for_send_cancel() = term()\n send_failed_reason() = {send_message_failed, reason_for_send_failure()}\n reason_for_send_failure() = term()\n other_reason() = term()\n AckData = ack_data()\n ack_data() = term()\n Extra = term()\n\nOptionally invoked for a transaction acknowledgement\n\nIf this function gets invoked or not, is controlled by the reply from the preceding call to handle_trans_request/3. The handle_trans_request/3 function may decide to return {handle_ack, ack_data()} or {handle_sloppy_ack, ack_data()} meaning that you need an immediate acknowledgement of the reply and that this function should be invoked to handle the acknowledgement.\n\nThe ack_data() argument to this function is the Erlang term returned by handle_trans_request/3.\n\nIf the AckStatus is ok, it is indicating that this is a true acknowledgement of the transaction reply.\n\nIf the AckStatus is {error, Reason}, it is an indication that the acknowledgement or even the reply (for which this is an acknowledgement) was not delivered, but there is no point in waiting any longer for it to arrive. This happens when:\n\nreply_timer\n The reply_timer eventually times out.\nreply send failure\n\nWhen megaco fails to send the reply (see handle_trans_reply), for whatever reason.\ncancel\n\nThe user has explicitly cancelled the wait (megaco:cancel/2).\nSee note above about the Extra argument in handle_trans_ack/5.\n\nhandle_unexpected_trans(ConnHandle, ProtocolVersion, Trans) -> ok\nhandle_unexpected_trans(ConnHandle, ProtocolVersion, Trans, Extra) -> ok\nTypes:\n ConnHandle = conn_handle()\n ProtocolVersion = protocol_version()\n Trans = #'TransactionPending'{} | #'TransactionReply'{} | #'TransactionResponseAck'{}\n Extra = term()\nInvoked when a unexpected message is received\nIf a reply to a request is not received in time, the megaco stack removes all info about the request from its tables. If a\nreply should arrive after this has been done the app has no way of knowing where to send this message. The message\nis delivered to the \"user\" by calling this function on the local node (the node which has the link).\nSee note above about the Extra argument in handle_unexpected_trans/4.\n\nhandle_trans_request_abort(ConnHandle, ProtocolVersion, TransNo, Pid) -> ok\nhandle_trans_request_abort(ConnHandle, ProtocolVersion, TransNo, Pid, Extra) -> ok\nTypes:\n ConnHandle = conn_handle()\n ProtocolVersion = protocol_version()\n TransNo = integer()\n Pid = undefined | pid()\n Extra = term()\nInvoked when a transaction request has been aborted\nThis function is invoked if the originating pending limit has been exceeded. This usually means that a request has\ntaken abnormally long time to complete.\nSee note above about the Extra argument in handle_trans_request_abort/5.\n\nhandle_segment_reply(ConnHandle, ProtocolVersion, TransNo, SegNo, SegCompl) -> ok\nhandle_segment_reply(ConnHandle, ProtocolVersion, TransNo, SegNo, SegCompl, Extra) -> ok\nTypes:\n ConnHandle = conn_handle()\n ProtocolVersion = protocol_version()\n TransNo = integer()\n SegNo = integer()\nSegCompl = asn1_NOVALUE | 'NULL'\nExtra = term()\n\nThis function is called when a segment reply has been received if the segment_reply_ind config option has been set to true.\n\nThis is in effect a progress report.\n\nSee note above about the Extra argument in handle_segment_reply/6.\nThis module contains the public interface to the flex scanner linked in driver. The flex scanner performs the scanning phase of text message decoding.\n\nThe flex scanner is written using a tool called `flex`. In order to be able to compile the flex scanner driver, this tool has to be available.\n\nBy default the flex scanner reports line-number of an error. But it can be built without line-number reporting. Instead token number is used. This will speed up the scanning some 5-10%. Use `--disable-megaco-flex-scanner-linenon` when configuring the application.\n\nThe scanner will, by default, be built as a reentrant scanner if the flex utility supports this (it depends on the version of flex). It is possible to explicitly disable this even when flex support this. Use `--disable-megaco-reentrant-flex-scanner` when configuring the application.\n\n**DATA TYPES**\n\n<table>\n<thead>\n<tr>\n<th>megaco_ports() = term()</th>\n</tr>\n</thead>\n</table>\n| megaco_version() = integer() \n >= 1 |\n\n**Exports**\n\n`start() -> {ok, PortOrPorts} | {error, Reason}`\n\nTypes:\n\n- `PortOrPorts = megaco_ports()`\n- `Reason = term()`\n\nThis function is used to start the flex scanner. It locates the library and loads the linked in driver.\n\nOn a single core system or if it's a non-reentrant scanner, a single port is created. On a multi-core system with a reentrant scanner, several ports will be created (one for each scheduler).\n\nNote that the process that calls this function **must** be permanent. If it dies, the port(s) will exit and the driver unload.\n\n`stop(PortOrPorts) -> stopped`\n\nTypes:\n\n- `PortOrPorts = megaco_ports()`\n\nThis function is used to stop the flex scanner. It also unloads the driver.\n\n`is_reentrant_enabled() -> Boolean`\n\nTypes:\n\n- `Boolean = boolean()`\n\nIs the flex scanner reentrant or not.\n\n`is_scanner_port(Port, PortOrPorts) -> Boolean`\n\nTypes:\n\n- `Port = port()`\nPortOrPorts = megaco_ports()\nBoolean = boolean()\n\nChecks if a port is a flex scanner port or not (useful when if a port exits).\n\nscan(Binary, PortOrPorts) -> {ok, Tokens, Version, LatestLine} | {error, Reason, LatestLine}\n\nTypes:\n Binary = binary()\n PortOrPorts = megaco_ports()\n Tokens = list()\n Version = megaco_version()\n LatestLine = integer()\n Reason = term()\n\nScans a megaco message and generates a token list to be passed on the parser.\nmegaco_codec_meas\n\nErlang module\n\nThis module implements a simple megaco codec measurement tool.\nResults are written to file (excel compatible text files) and on stdout.\nNote that this module is not included in the runtime part of the application.\n\nExports\n\nstart() -> void()\nstart(MessagePackage) -> void()\n\nTypes:\n\n MessagePackageRaw = message_package()\n message_package() = atom()\n\nThis function runs the measurement on all the official codecs; pretty, compact, ber, per and erlang.\nErlang module\n\nThis module implements the \\texttt{mstone1} tool, a simple megaco codec-based performance tool.\n\nThe results, the mstone value(s), are written to stdout.\n\n\\textbf{Note} that this module is \\textbf{not} included in the runtime part of the application.\n\n\\section*{Exports}\n\n\\begin{verbatim}\nstart() -> void()\nstart(MessagePackage) -> void()\nstart(MessagePackage, Factor) -> void()\n\nTypes:\n MessagePackage = message_package()\n message_package() = atom()\n Factor() = integer() > 0\n\nThis function starts the \\texttt{mstone1} performance test with all codec configs. \\texttt{Factor} (defaults to 1) processes are started for every supported codec config.\n\nEach process encodes and decodes their messages. The number of messages processed in total (for all processes) is the mstone value.\n\nstart_flex() -> void()\nstart_flex(MessagePackage) -> void()\nstart_flex(MessagePackage, Factor) -> void()\n\nTypes:\n MessagePackage = message_package()\n message_package() = atom()\n Factor() = integer() > 0\n\nThis function starts the \\texttt{mstone1} performance test with only the flex codec configs (i.e. \\texttt{pretty} and \\texttt{compact} with \\texttt{flex}). The same number of processes are started as when running the standard test (using the \\texttt{start/0,1} function).\n\nEach process encodes and decodes their messages. The number of messages processed in total (for all processes) is the mstone value.\n\nstart_only_drv() -> void()\nstart_only_drv(MessagePackage) -> void()\nstart_only_drv(MessagePackage, Factor) -> void()\n\nTypes:\n MessagePackage = message_package()\n message_package() = atom()\n Factor() = integer() > 0\n\nThis function starts the \\texttt{mstone1} performance test with only the driver using codec configs (i.e. \\texttt{pretty} and \\texttt{compact} with \\texttt{flex}, and \\texttt{ber} and \\texttt{per} with \\texttt{driver} and \\texttt{erlang} with \\texttt{compressed}). The same number of processes are\nstarted as when running the standard test (using the start/0,1 function). Each process encodes and decodes their messages. The number of messages processed in total (for all processes) is the mstone value.\n\n```erlang\nstart_no_drv() -> void()\nstart_no_drv(MessagePackage) -> void()\nstart_no_drv(MessagePackage, Factor) -> void()\n```\n\nTypes:\n- `MessagePackage = message_package()`\n- `message_package() = atom()`\n- `Factor() = integer() > 0`\n\nThis function starts the `mstone1` performance test with codec configs not using any drivers (i.e. pretty and compact without flex, ber and per without driver and erlang without compressed). The same number of processes are started as when running the standard test (using the `start/0,1` function). Each process encodes and decodes their messages. The number of messages processed in total (for all processes) is the mstone value.\nmegaco_codec_mstone2\n\nErlang module\n\nThis module implements the mstone2 tool, a simple megaco codec-based performance tool. The results, the mstone value(s), are written to stdout.\n\nNote that this module is not included in the runtime part of the application.\n\nExports\n\nstart() -> void()\nstart(MessagePackage) -> void()\n\nTypes:\n\nMessagePackage = message_package()\nmessage_package() = atom()\n\nThis function starts the mstone2 performance test with all codec configs. Processes are created dynamically. Each process makes one run through their messages (decoding and encoding messages) and then exits. When one process exits, a new is created with the same codec config and set of messages.\n\nThe number of messages processed in total (for all processes) is the mstone value.\nmegaco_codec_transform\n\nErlang module\n\nThis module implements a simple megaco message transformation utility.\n\n**Note** that this module is **not** included in the runtime part of the application.\n\n**Exports**\n\n```erlang\nexport_messages() -> void()\nexport_messages(MessagePackage) -> void()\n```\n\n**Types:**\n\n```erlang\n MessagePackage = atom()\n```\n\nExport the messages in the `MessagePackage` (default is `time_test`).\n\nThe output produced by this function is a directory structure with the following structure:\n\n```\n<message package>/pretty/<message-files>\n compact/<message-files>\n per/<message-files>\n ber/<message-files>\n erlang/<message-files>\n```"}}},{"rowIdx":86,"cells":{"id":{"kind":"string","value":"f4f748269c168cbfdd4424c938012f56ab31e64a"},"text":{"kind":"string","value":"Bridge Implementation\n\nVersion 1 Release 4\nBridge Implementation\n\n*Version 1 Release 4*\nTivoli NetView for OS/390 Bridge Implementation\n\nCopyright Notice\n\n© Copyright IBM Corporation 1997, 2001. All rights reserved. May only be used pursuant to a Tivoli Systems Software License Agreement, an IBM Software License Agreement, or Addendum for Tivoli Products to IBM Customer or License Agreement. No part of this publication may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any computer language, in any form or by any means, electronic, mechanical, magnetic, optical, chemical, manual, or otherwise, without prior written permission of IBM Corporation. IBM Corporation grants you limited permission to make hardcopy or other reproductions of any machine-readable documentation for your own use, provided that each such reproduction shall carry the IBM Corporation copyright notice. No other rights under copyright are granted without prior written permission of IBM Corporation. The document is not intended for production and is furnished “as is” without warranty of any kind. All warranties on this document are hereby disclaimed, including the warranties of merchantability and fitness for a particular purpose.\n\nU.S. Government Users Restricted Rights—Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corporation.\n\nTrademarks\n\nIBM, the IBM logo, Tivoli, the Tivoli logo, AIX, AnyNet, APPN, AT, C/370, CICS, DB2, IMS, KnowledgeTool, Language Environment, LPDA, MVS/ESA, NetFinity, NetView, OPC, OS/2, OS/390, RACF, RS/6000, Tivoli Global Enterprise Manager, Tivoli Enterprise Console, Tivoli Management Framework, TME 10, VM/ESA, VSE/ESA, and VTAM are trademarks or registered trademarks of International Business Machines Corporation or Tivoli Systems Inc. in the United States, other countries, or both.\n\nMicrosoft, Windows, Windows NT, and the Windows logo are trademarks of Microsoft Corporation in the United States, other countries, or both.\n\nUNIX is a registered trademark of The Open Group in the United States and other countries.\n\nOther company, product, and service names may be trademarks or service marks of others.\n\nNotices\n\nReferences in this publication to Tivoli Systems or IBM products, programs, or services do not imply that they will be available in all countries in which Tivoli Systems or IBM operates. Any reference to these products, programs, or services is not intended to imply that only Tivoli Systems or IBM products, programs, or services can be used. Subject to valid intellectual property or other legally protectable right of Tivoli Systems or IBM, any functionally equivalent product, program, or service can be used instead of the referenced product, program, or service. The evaluation and verification of operation in conjunction with other products, except those expressly designated by Tivoli Systems or IBM, are the responsibility of the user. Tivoli Systems or IBM may have patents or pending patent applications covering subject matter in this document. The furnishing of this document does not give you any license to these patents. You can send license inquiries, in writing, to the IBM Director of Licensing, IBM Corporation, North Castle Drive, Armonk, New York 10504-1785, U.S.A.\n\nProgramming Interfaces\n\nThis publication documents intended Programming Interfaces that allow the customer to write programs to obtain services of Tivoli NetView for OS/390.\n# Contents\n\n**Preface** ................................................................. vii\nWho Should Read This Document ........................................ vii\nPrerequisite and Related Documents .................................... viii\nWhat This Document Contains ........................................... viii\nConventions Used in This Document .................................... viii\nPlatform-specific Information .......................................... viii\nTerminology ....................................................................... viii\nReading Syntax Diagrams .................................................... ix\n Required Syntax ................................................................ ix\n Optional Keywords and Variables ...................................... x\n Default Values .................................................................. x\n Long Syntax Diagrams ................................................... xi\n Syntax Fragments .......................................................... xi\n Highlighting, Brackets, and Braces .................................... xii\n Abbreviations .................................................................. xiii\nAccessing Publications Online ............................................. xiv\nOrdering Publications ....................................................... xiv\nProviding Feedback about Publications ................................. xiv\nContacting Customer Support ............................................. xiv\n\n## Chapter 1. Introduction to NetView Bridge and NetView Bridge Remote Access\n\nAccess ............................................................................... 1\nUnderstanding NetView Bridge .............................................. 1\nUnderstanding NetView Bridge Remote Access ......................... 1\nHow NetView Bridge Functions ............................................. 1\nHow NetView Bridge Remote Access Functions ......................... 3\nComponents of NetView Bridge .............................................. 4\n Database Server .......................................................... 4\n NetView Server Support API ........................................... 5\n User-Written Command Procedures .................................... 5\n NetView Bridge Requester API ......................................... 5\n Bridge Dispatcher .......................................................... 5\n Transaction Processors ................................................... 6\n Remote Bridge Dispatchers (Remote Access Only) .................. 6\n NetView Subsystem Address Space .................................... 6\n\n## Chapter 2. Setting up NetView Bridge and NetView Bridge Remote Access\n\nActivity Checklist ............................................................ 7\nSoftware Requirements ...................................................... 8\nPreparing to Set Up NetView Bridge ...................................... 8\n Step 1. Adding an Operator ID for the Dispatcher Autotask ....... 8\n Step 2. Creating a NetView Bridge Dispatcher Profile ............. 8\n Step 3. Adding NetView Bridge Command Model Statements to the NetView Program ........................................ 9\n Step 4. Creating a Server to Work with the NetView Program and Your Target Database ...................................... 9\n Step 5. Creating a New Transaction Processor for an Existing Server .................................................. 10\n Step 6. Creating NetView Command Procedures .................... 10\n Step 7. Determining Whether to Use Multiple Copies of a Database Server ........................................ 10\n Step 8. Assigning Queue Names to Database Servers .............. 10\n Completing the Initial Setup of NetView Bridge ...................... 11\nPreparing to Set Up Remote Access to NetView Bridge .............. 11\nStep 1. Adding an Operator ID for the Remote Dispatcher Autotask ................................ 11\nStep 2. Creating a NetView Bridge Remote Dispatcher Profile ........................................... 11\nStep 3. Adding NetView Bridge Remote Access Command Model Statements to NetView ........ 12\nStep 4. Creating NetView Command Procedures ................................................................. 12\n\nChapter 3. Creating a Database Server .............................................................................. 15\nDocumenting Your Database Server .................................................................................... 15\nCoding a Database Server with the Server Support API Using PL/I ..................................... 15\n Run-Time Options for PL/I .................................................................................................. 15\n Types of Parameters Passed to the Server Support API Service Routines for PL/I .............. 15\n Control Blocks for PL/I ..................................................................................................... 16\n Return Codes for PL/I ........................................................................................................ 16\nCoding a Database Server with the Server Support API Using C ........................................ 16\n Run-Time Options for C ..................................................................................................... 16\n Types of Parameters Passed to the Server Support API Service Routines for C .................. 16\n Control Blocks for C .......................................................................................................... 16\n Return Codes for C ............................................................................................................ 17\nCreating Database Server Control Code ............................................................................. 17\n Initializing the Database Server ......................................................................................... 17\n Controlling Flow ................................................................................................................ 18\n Terminating the Database Server ....................................................................................... 20\nCreating a Transaction Processor ........................................................................................ 20\n Designing the Transaction .................................................................................................. 20\n Processing the Transaction Request .................................................................................. 20\n Interacting with the Database Interface ............................................................................. 21\n Setting Up the Transaction Parameter Blocks .................................................................. 21\n Forwarding the Transaction Reply .................................................................................... 22\nCompiling and Link-Editing a Database Server with the Server Support API in PL/I ................ 22\n Compiling Considerations for PL/I ..................................................................................... 22\n Link-Editing Considerations for PL/I ............................................................................... 23\nCompiling and Link-Editing a Database Server with the Server Support API in C ..................... 23\n Compiling Considerations for C ....................................................................................... 23\n Link-Editing Considerations for C .................................................................................... 24\nExample PL/I Program Using the Server Support API .......................................................... 24\nExample C Program Using the Server Support API .............................................................. 41\nAssembler Source Code for Obtaining the Address of the Communications ECB .................. 51\n\nChapter 4. Writing a NetView Bridge Command Procedure Using the NetView Bridge Requestor API ........................................................................................................ 55\nUnderstanding Transaction Size Limitations ....................................................................... 55\n Header Information .............................................................................................................. 55\n User Data ............................................................................................................................ 55\n Packaging Code .................................................................................................................. 55\n Size of a Parameter ............................................................................................................. 55\n Total Size of a Transaction ................................................................................................. 56\nWriting Command Procedures Using REXX or the NetView Command List Language ............. 56\n Step 1. Initializing Parameters ............................................................................................ 56\n Step 2. Preparing to Receive the Reply .............................................................................. 56\n Step 3. Sending the Transaction Request .......................................................................... 57\n Step 4. Processing the Reply .............................................................................................. 57\nPreface\n\nThis book explains how to plan for and implement the NetView® Bridge function of the NetView program. This includes accessing NetView Bridge remotely.\n\nNetView Bridge is a set of application programming interfaces (APIs) that allows the NetView program to interact with various types of databases in the MVS environment when combined with a database server, such as Information/System-NetView Bridge Adapter. You can use NetView Bridge to write automation applications that can access data stored in your MVS database and can transport data between the NetView program and your database.\n\nIn addition to accessing your database from the MVS environment, NetView Bridge can remotely access your MVS database from the MVS environment. To remotely access your database, you must install NetView Bridge on the host MVS system where your database resides and install NetView Bridge remote access functions on your remote NetView system.\n\nStep-by-step instructions tell you how to set up and customize NetView Bridge and NetView Bridge remote access for your environment. After you complete these instructions, your NetView Bridge and NetView Bridge remote access functions will be operational.\n\nWho Should Read This Document\n\nSystem programmers and NetView operators should use this book to set up and customize the NetView Bridge and NetView Bridge remote access functions. Use this document when you are installing the NetView program and when you code applications that use the functions of NetView Bridge.\n\nAs a programmer or NetView operator, you should be familiar with the MVS operating system and your target database. If you access NetView Bridge remotely, you should also be familiar with the remote operating system. If you have purchased a database server, such as Information/System-NetView Bridge Adapter, you should be familiar with how to install the database server.\n\nIn addition, you should know how to create and alter job control language (JCL) statements. It is helpful to have a thorough understanding of one of the following: the Restructured Extended Executor (REXX) language, the NetView command list language, PL/I, or C.\n\nPrerequisite and Related Documents\n\nTo read about the new functions offered in this release, refer to the *Tivoli NetView for OS/390 Installation: Getting Started*.\n\nYou can find additional product information on these Internet sites:\n\n<table>\n<thead>\n<tr>\n<th>Resource Address (URL)</th>\n<th>URL</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>IBM</td>\n<td><a href=\"http://www.ibm.com/\">http://www.ibm.com/</a></td>\n</tr>\n<tr>\n<td>Tivoli Systems</td>\n<td><a href=\"http://www.tivoli.com/\">http://www.tivoli.com/</a></td>\n</tr>\n<tr>\n<td>Tivoli NetView for OS/390</td>\n<td><a href=\"http://www.tivoli.com/nv390\">http://www.tivoli.com/nv390</a></td>\n</tr>\n</tbody>\n</table>\nPreface\n\nThe Tivoli NetView for OS/390 home page offers demonstrations of NetView, related products, and several free NetView applications you can download. These applications can help you with tasks such as:\n\n- Getting statistics for your automation table and merging the statistics with a listing of the automation table\n- Displaying the status of a JES job or cancelling a specified JES job\n- Sending alerts to NetView using the program-to-program interface (PPI)\n- Sending and receiving MVS commands using the PPI\n- Sending TSO commands and receiving responses\n\nWhat This Document Contains\n\nThis document provides an overview of NetView Bridge and NetView Bridge remote access. It describes how to set up, create a database, and write a command procedure. This document also describes how to use NetView Bridge, optimize it for best performance, and explains how to report any problems you might have. The appendixes include special information that might prove helpful when using NetView Bridge.\n\nConventions Used in This Document\n\nThe document uses several typeface conventions for special terms and actions. These conventions have the following meaning:\n\n**Bold** Commands, keywords, flags, and other information that you must use literally appear like this, in bold.\n\n*Italics* Variables and new terms appear like this, in italics. Words and phrases that are emphasized also appear like this, in italics.\n\n**Monospace** Code examples, output, and system messages appear like this, in a monospace font.\n\n**ALL CAPS** Tivoli NetView for OS/390 commands are in ALL CAPITAL letters.\n\nPlatform-specific Information\n\nFor more information about the hardware and software requirements for NetView components, refer to the Tivoli NetView for OS/390 Licensed Program Specification.\n\nTerminology\n\n\nFor brevity and readability, the following terms are used in this document:\n\n**NetView**\n\n- Tivoli NetView for OS/390 Version 1 Release 4\n- Tivoli NetView for OS/390 Version 1 Release 3\n- TME 10 NetView for OS/390 Version 1 Release 2\n- TME 10 NetView for OS/390 Version 1 Release 1\n- IBM NetView for MVS Version 3\n- IBM NetView for MVS Version 2 Release 4\n- IBM NetView Version 2 Release 3\nMVS\nMVS/ESA, OS/390, or z/OS operating systems.\n\nTivoli Enterprise software\nTivoli software that manages large business networks.\n\nTivoli environment\nThe Tivoli applications, based upon the Tivoli Management Framework, that are installed at a specific customer location and that address network computing management issues across many platforms. In a Tivoli environment, a system administrator can distribute software, manage user configurations, change access privileges, automate operations, monitor resources, and schedule jobs. You may have used TME 10 environment in the past.\n\nTME 10\nIn most product names, TME 10 has been changed to Tivoli.\n\nV and R\nSpecifies the version and release.\n\nVTAM and TCP/IP\nVTAM and TCP/IP for OS/390 are included in the IBM Communications Server for OS/390 element of the OS/390 operating system. Refer to http://www.software.ibm.com/enetwork/commserver/about/csos390.html.\n\nUnless otherwise indicated, references to programs indicate the latest version and release of the programs. If only a version is indicated, the reference is to all releases within that version.\n\nWhen a reference is made about using a personal computer or workstation, any programmable workstation can be used.\n\nReading Syntax Diagrams\nSyntax diagrams start with double arrowheads on the left (►) and move along the main line until they end with two arrowheads facing each other (◄). As shown in the following table, syntax diagrams use position to indicate the required, optional, and default values for keywords, variables, and operands.\n\n<table>\n<thead>\n<tr>\n<th>Element Position</th>\n<th>Meaning</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>On the command line</td>\n<td>Required</td>\n</tr>\n<tr>\n<td>Above the command line</td>\n<td>Default</td>\n</tr>\n<tr>\n<td>Below the command line</td>\n<td>Optional</td>\n</tr>\n</tbody>\n</table>\n\nTable 2. How the Position of Syntax Diagram Elements Is Used\n\nRequired Syntax\nThe command name, required keywords, variables, and operands are always on the main syntax line. Figure 1 on page x specifies that the resname variable must be used for the CCPLOADF command.\nKeywords and operands are written in uppercase letters. Lowercase letters indicate variables such as values or names that you supply. In Figure 2, MEMBER is an operand and membername is a variable that defines the name of the data set member for that operand.\n\nFigure 1. Required Syntax Elements\n\nOptional Keywords and Variables\n\nOptional keywords, variables, and operands are below the main syntax line. Figure 3 specifies that the ID operand can be used for the DISPREG command, but is not required.\n\nFigure 2. Syntax for Variables\n\nFigure 3. Optional Syntax Elements\n\nDefault Values\n\nDefault values are above the main syntax line. If the default is a keyword, it appears only above the main line. You can specify this keyword or allow it to default.\n\nIf an operand has a default value, the operand appears both above and below the main line. A value below the main line indicates that if you choose to specify the operand, you must also specify either the default value or another value shown. If you do not specify an operand, the default value above the main line is used.\n\nFigure 4 on page xi shows the default keyword STEP above the main line and the rest of the optional keywords below the main line. It also shows the default values for operands MODNAME=* and OPTION=* above and below the main line.\nLong Syntax Diagrams\n\nWhen more than one line is needed for a syntax diagram, the continued lines end with a single arrowhead (►). The following lines begin with a single arrowhead (►), as shown in Figure 4.\n\nSyntax Fragments\n\nCommands that contain lengthy groups or a section that is used more than once in a command are shown as separate fragments following the main diagram. The fragment name is shown in mixed case. See Figure 5 on page xii for a syntax with the fragments ReMote and FromTo.\nCommas and Parentheses\n\nRequired commas and parentheses are included in the syntax diagram. When an operand has more than one value, the values are typically enclosed in parentheses and separated by commas. In Figure 6 on page xiii, the OP operand, for example, contains commas to indicate that you can specify multiple values for the testop variable.\nIf a command requires positional commas to separate keywords and variables, the commas are shown before the keyword or variable, as in Figure 4 on page xi.\n\nFor example, to specify the BOSESS command with the *sessid* variable, enter:\n\n```\nNCCF BOSESS applid,,sessid\n```\n\nYou do not need to specify the trailing positional commas. Positional and non-positional trailing commas either are ignored or cause the command to be rejected. Restrictions for each command state whether trailing commas cause the command to be rejected.\n\n### Highlighting, Brackets, and Braces\n\nSyntax diagrams do not rely on highlighting, underscoring, brackets, or braces; variables are shown italicized in hardcopy or in a differentiating color for NetView help and BookManager online books.\n\nIn parameter descriptions, the appearance of syntax elements in a diagram immediately tells you the type of element. See Table 3 for the appearance of syntax elements.\n\n#### Table 3. Syntax Elements Examples\n\n<table>\n<thead>\n<tr>\n<th>This element...</th>\n<th>Looks like this...</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Keyword</td>\n<td>CCPLOADF</td>\n</tr>\n<tr>\n<td>Variable</td>\n<td><em>resname</em></td>\n</tr>\n<tr>\n<td>Operand</td>\n<td>MEMBER=<em>membername</em></td>\n</tr>\n<tr>\n<td>Default</td>\n<td><em>today</em> or INCL</td>\n</tr>\n</tbody>\n</table>\n\n### Abbreviations\n\nCommand and keyword abbreviations are described in synonym tables after each command description.\nAccessing Publications Online\n\nThe Tivoli Customer Support Web site (http://www.tivoli.com/support/) offers a guide to support services (the Customer Support Handbook); frequently asked questions (FAQs); and technical information, including release notes, user’s guides, redbooks, and white papers. You can access Tivoli publications online at http://www.tivoli.com/support/documents/. The documentation for some products is available in PDF and HTML formats. Translated documents are also available for some products.\n\nTo access most of the documentation, you need an ID and a password. To obtain an ID for use on the support Web site, go to http://www.tivoli.com/support/getting/.\n\nResellers should refer to http://www.tivoli.com/support/smb/index.html for more information about obtaining Tivoli technical documentation and support.\n\nBusiness Partners should refer to [Ordering Publications] for more information about obtaining Tivoli technical documentation.\n\nNote: Additional support is also available on the NETVIEW CFORUM (Customer Forum) through the IBMLink system. This forum is monitored by NetView developers who answer questions and provide guidance. When a problem with the code is found, you are asked to open an official problem management record (PMR) to get resolution.\n\nOrdering Publications\n\nOrder Tivoli publications online at http://www.tivoli.com/support/Prodman/html/pub_order.html or by calling one of the following telephone numbers:\n\n- U.S. customers: (800) 879-2755\n- Canadian customers: (800) 426-4968\n\nProviding Feedback about Publications\n\nWe are very interested in hearing about your experience with Tivoli products and documentation, and we welcome your suggestions for improvements. If you have comments or suggestions about our products and documentation, contact us in one of the following ways:\n\n- Send e-mail to pubs@tivoli.com.\n- Fill out our customer feedback survey at http://www.tivoli.com/support/survey/.\n\nContacting Customer Support\n\nThe Tivoli Customer Support Handbook at http://www.tivoli.com/support/handbook/ provides information about all aspects of Tivoli Customer Support, including the following:\n\n- Registration and eligibility\n- How to contact support, depending on the severity of your problem\n- Telephone numbers and e-mail addresses, depending on the country you are in\n- What information you should gather before contacting support\nChapter 1. Introduction to NetView Bridge and NetView Bridge Remote Access\n\nThis chapter describes the functions and requirements for NetView Bridge and NetView Bridge remote access. NetView Bridge provides a set of application programming interfaces (APIs) that gives you an effective means of connecting an MVS NetView program to target databases or transaction processors. You can also access target databases from a remote MVS, VM, or VSE system through the resident NetView program running in MVS, using the NetView high performance transport.\n\nUnderstanding NetView Bridge\n\nThe NetView program collects data from the resources in your network. This data includes information about session awareness, system configuration, and problems within your network.\n\nNetView Bridge can help track information concerning your resources, network, or configuration by creating and updating records in a non-NetView database. This database must reside on an MVS system.\n\nThe NetView program collects data that might make updates necessary to your configuration database. NetView Bridge allows you to write applications that can access data stored in a configuration database and transport data between the NetView program and your database. These programs can update your database as often as necessary.\n\nYou can update data and transfer data to your database by using the NetView Bridge Requester API and the server support API. These functions use high-level language (HLL) programs and user-written command lists to perform your work. You can invoke target database functions that are not in the NetView address space and develop your own transaction processors.\n\nUnderstanding NetView Bridge Remote Access\n\nNetView Bridge uses the NetView Bridge Requester API to access servers that reside on hosts other than the one in which the transaction was generated. You can collect data from the resources in your network and create and update records in a database residing in an MVS system. Using the remote dispatcher, a NetView program running on a remote MVS, VM, or VSE operating system can access these records.\n\nTransactions are forwarded to the resident host, which is an MVS system running NetView Bridge, by using the NetView high performance transport API, which allows applications in two network nodes to communicate over an LU 6.2 session.\n\nHow NetView Bridge Functions\n\nNetView Bridge uses APIs, a bridge dispatcher, servers, and transaction processors that must be installed in your host. The primary components of NetView Bridge are shown in Figure 7 on page 3.\n\nTo access your database, a transaction (the transaction request and the data required to process it) should flow in the following manner:\nA user-written command procedure (NetView command list language, REXX, or HLL program) uses the NetView Bridge Requester API to request that a transaction be sent to a database server. Examples of user-written command procedures and information about how to write these procedures are in \"Chapter 4. Writing a NetView Bridge Command Procedure Using the NetView Bridge Requestor API\" on page 53.\n\nThe bridge dispatcher passes this request to the input queue of an available database server in the program-to-program interface.\n\nA database server, such as the Information/System-NetView Bridge Adapter, uses the server support API to execute a transaction. The server performs the requested transaction, such as IBUPDATE of the Information/System-NetView Bridge Adapter, by invoking the appropriate transaction processor. This transaction processor works directly with the target database.\n\nIf the transaction processor creates a reply for this request, it uses the server support API to pass the reply to the bridge dispatcher through the output queue in the program-to-program interface. The bridge dispatcher then returns the reply to a user-written command procedure in the form of a message.\n\nA user-written command procedure uses the NetView Bridge Requester API, specifically the TRANRCV command or the CNMGETP service routine, to extract the reply data from the message.\nHow NetView Bridge Remote Access Functions\n\nNetView Bridge remote access functions allow you to access your MVS database from a remote NetView program by sending requests to a resident NetView Bridge operating in an MVS system. The primary components of NetView Bridge remote access are shown in Figure 7. NetView Bridge uses user-written command procedures, APIs, the remote dispatcher, servers, the program-to-program interface, and transaction processors that must be installed in your host for remote access.\n\nFor remote access to your database, a transaction should flow in the following manner:\n\nFigure 7. Primary Components of NetView Bridge\nA user-written command procedure (NetView command list language, REXX, or HLL program in an MVS system) uses the NetView Bridge Requester API to request that a transaction be sent to the remote dispatcher. Examples of user-written command procedures and information about how to write these procedures are in Chapter 4, Writing a NetView Bridge Command Procedure Using the NetView Bridge Requestor API on page 55.\n\nThe NetView high performance transport API (DSIHPDST) acts as an interface between the remote NetView system and the resident NetView system running in MVS to send the request to the remote dispatcher in the resident NetView system.\n\nThe remote dispatcher sends the request to the bridge dispatcher running in the resident NetView system.\n\nThe bridge dispatcher passes this request to the input queue of an available database server in the program-to-program interface.\n\nA database server, such as the Information/System-NetView Bridge Adapter, uses the server support API to retrieve the transaction. The server performs the requested transaction by invoking the appropriate transaction processor. This transaction processor works directly with the target database.\n\nIf the transaction processor creates a reply for this request, it uses the server support API to pass the reply to the bridge dispatcher through the output queue in the program-to-program interface.\n\nThe bridge dispatcher uses the NetView high performance transport API to send the reply to the remote dispatcher on the remote NetView system.\n\nThe remote dispatcher sends the reply to the user-written command procedure in the form of a message.\n\nA user-written command procedure uses the NetView Bridge Requester API, specifically the TRANRCV command or the CNMGETP service routine, to extract the reply data from the message.\n\nComponents of NetView Bridge\n\nYou need a database server, a server support API, user-written command procedures, a NetView Bridge Requester API, a bridge dispatcher, and transaction processors to enable NetView Bridge to work. If the NetView program is running on a remote operating system, the remote bridge dispatcher is required. NetView Bridge also uses the NetView subsystem address space as the program-to-program interface. The following are descriptions of these components.\n\nDatabase Server\n\nA database server connects the NetView program and the target database. A database server consists of one or more transaction processors that run in an address space outside of the NetView program.\n\nWhen a database server is started, an address space is created and the server support API is initialized. The server waits for a transaction to arrive in its server-defined input queue. When a transaction is received, the server invokes the appropriate transaction processor to perform the work.\nIf the transaction processor generates a response, the database server sends that response back to the NetView program using the server support API to send to the output queue, which the bridge dispatcher monitors. The database server then waits for another transaction.\n\nWhen you request termination of the database server, the database server terminates the server support API and the address space.\n\nMultiple servers allow you to process multiple transactions in parallel. Adding additional servers can help you handle increased throughput as your transaction volume increases, but you should expect performance trade-offs. Consult your database server documentation for instructions on how to create more copies of a server.\n\nYou can purchase a server for certain databases, such as the Information/System-NetView Bridge Adapter for the Information/Management database from IBM®, or you can develop one yourself using the server support API. See \"Chapter 3. Creating a Database Server\" on page 13 for more information on creating a database server using the server support API.\n\n**NetView Server Support API**\n\nThe NetView server support API provides services to your database server. Your database server uses the server support API to initialize the API, to receive transactions, to send responses back to the NetView program, and to terminate the API.\n\n**User-Written Command Procedures**\n\nYou use the NetView Bridge commands in your automation applications. To access a server from the NetView program, you must invoke NetView Bridge commands using the NetView command list language, REXX, or a high-level language (HLL) in an MVS system. Examples of user-written command procedures and information about how to write these procedures are in \"Chapter 4. Writing a NetView Bridge Command Procedure Using the NetView Bridge Requestor API\" on page 55.\n\n**NetView Bridge Requester API**\n\nThe NetView Bridge Requester API handles the commands in your command procedures, passing transaction requests to the transaction processors. The NetView Bridge Requester API returns a response to your command procedures (if one is expected) and must be invoked to get the reply data.\n\n**Bridge Dispatcher**\n\nA NetView bridge dispatcher runs as an autotask, which is a task that does not require a terminal or a logged-on user. This dispatcher is present only in the MVS host on which the target database resides.\n\nA bridge dispatcher executes the NetView Bridge command RTRINIT to establish the NetView Bridge environment and pass transactions between user-written command procedures and database servers. The bridge dispatcher places transactions in the input queue in the program-to-program interface for an available database server.\n\nThe RTRINIT command is driven by the profile of a NetView autotask. This autotask serves as the interface to a specific set of database servers and defines three user-provided queue names to the program-to-program interface. These queues are...\nthe output queue, to which the database servers send all their output, the ready queue, which contains ready tokens indicating which database servers are available, and the hold queue, which holds transaction requests when no database servers are available. For information on the program-to-program interface, refer to \"Understanding the NetView Program-to-Program Interface\" in the *Tivoli NetView for OS/390 Application Programmer’s Guide*.\n\nAs shown in Figure 7 on page 3, more than one copy of a server can interface with a bridge dispatcher. One or more server copies per bridge dispatcher are collectively referred to as a server set. If your server set consists of more than one server, each copy of the server must be functionally identical.\n\nYou can define more than one bridge dispatcher to your NetView system by defining multiple autotasks. Each bridge dispatcher can have one or more copies of a server assigned to it. Each server set sends output to a single output queue.\n\nThe bridge dispatcher can also communicate with a remote bridge dispatcher by using the NetView high performance transport API (DSIHPDST).\n\n**Transaction Processors**\n\nA database server can contain one or more transaction processors. These transaction processors interact directly with the database. The effect of transactions and the use of the fields within them depend upon the transaction processor and how it works with the database. Only the format of transactions is defined by NetView Bridge.\n\n**Remote Bridge Dispatchers (Remote Access Only)**\n\nA remote bridge dispatcher runs as a NetView autotask and executes the REMOTEBR command to register the remote dispatcher with the NetView high performance transport (DSIHPDST). The dispatcher enables transactions to be passed between user-written command procedures on the remote host and the MVS host on which the target database resides.\n\nTwo remote dispatchers are required for remote function of NetView Bridge: one in the MVS host on which the target database resides, and one on the remote MVS, VM, or VSE system.\n\n**NetView Subsystem Address Space**\n\nThe NetView subsystem address space contains the program-to-program interface queues used by NetView Bridge. You must recycle the NetView Bridge dispatcher autotask and the database server every time a new program-to-program interface is activated.\nChapter 2. Setting up NetView Bridge and NetView Bridge Remote Access\n\nThis chapter contains the steps for setting up NetView Bridge and NetView Bridge remote access. An activity checklist is included to help you track your progress.\n\nBefore you proceed with this chapter, your system and the NetView program installation must meet certain criteria:\n\n- The NetView program must be installed according to the installation guides included with the product. If you intend to use one of the high-level languages (HLLs) to create NetView Bridge command procedures, you must have completed the procedures for using high-level languages with the NetView program.\n- You must have a database server, such as Information/System-NetView Bridge Adapter, or write your own database server.\n- Your target database must reside on the same system as NetView Bridge.\n- If you are using remote access, a remote dispatcher must be running on both your target NetView (MVS) system and on your remote NetView (MVS, VM, or VSE) system. The NetView Bridge dispatcher must be running on your MVS target NetView system.\n\nActivity Checklist\n\nSuccessfully setting up NetView Bridge and NetView Bridge remote access involves several activities. The following is an overview of the activities that you perform in subsequent chapters in this book. You can use this overview as a checklist.\n\n1. Perform the steps in this chapter (beginning with \"Preparing to Set Up NetView Bridge\" on page 8) to set up and customize NetView Bridge. Follow each step in order, completing each step before proceeding to the next.\n\n2. Perform the steps in this chapter (beginning with \"Preparing to Set Up Remote Access to NetView Bridge\" on page 11) to set up NetView Bridge remote access. Follow each step in order, completing each step before proceeding to the next.\n\n3. If you intend to create your own database server, follow the instructions in \"Chapter 3. Creating a Database Server\" on page 15 to create the appropriate interface. If you have a database server, such as Information/System-NetView Bridge Adapter, see the documentation provided with the database server for information on how to install your server.\n\n4. Follow the instructions in \"Chapter 4. Writing a NetView Bridge Command Procedure Using the NetView Bridge Requestor API\" on page 55 to write command procedures for using the NetView Bridge Requester API.\n\n5. Follow the steps in \"Chapter 5. Starting NetView Bridge, a Database Server, and NetView Bridge Remote Access\" on page 79 to start NetView Bridge in your environment.\n\n6. Optimize the performance of NetView Bridge. Some performance considerations are outlined in \"Chapter 6. Adjusting NetView Bridge to Optimize Performance\" on page 83. Other performance issues are probably unique to your installation.\nSoftware Requirements\n\nThe following are the software requirements for NetView Bridge (local or remote access):\n\n- VTAM® Version 4 Release 3 or a later release installed in a resident MVS host\n- TME® 10 NetView for OS/390® Version 1 Release 1 (program number 5697-B82), or a later release\n\nFor VM and VSE you need the following:\n\n- VTAM Version 3 Release 3 or a later release\n- NetView Version 2 Release 3 running under VM/ESA® (program number 5756-051), or VSE/ESA™ (program number 5686-038)\n\nPreparing to Set Up NetView Bridge\n\nYou might have multiple installations of the NetView program on your system. Regardless of the system they are installed on, any of the NetView programs are eligible to interact with your database through NetView Bridge installed on your MVS NetView system. You need to choose one of your MVS NetView systems on which to activate a NetView Bridge dispatcher and its associated server set. This is your resident NetView system. Once you have made this choice, you are ready to proceed with the setup steps on the following pages.\n\nNote: Do not bypass any of the steps in this section. Ensure that you complete each task within each step (in order) before proceeding to the next step.\n\nStep 1. Adding an Operator ID for the Dispatcher Autotask\n\nThe DSIOPF member of DSIPARM contains an operator ID, BRIGOPER, that you can customize with your own unique operator ID and profile name (prfname). This ID serves as the NetView interface to the database servers and is the destination task for NetView Bridge Requester API requests.\n\nNote: Your bridge dispatcher autotasks should be exclusive to NetView Bridge.\n\nTo define the ID, you must modify the DSIOPF member of DSIPARM. For example, in the following OPERATOR statement, replace the highlighted name (BRIGOPER) with the unique operator ID that you have selected, and replace prfname with the name of the profile that you have selected.\n\n```\nBRIGOPER OPERATOR PROFILEN=prfname\n```\n\nThis change takes effect the next time you recycle the NetView program.\n\nStep 2. Creating a NetView Bridge Dispatcher Profile\n\nYou must create a new member in the NetView data set DSIPRF with the same name (prfname) that you selected in Step 1. This member authorizes the operator to act as a NetView Bridge dispatcher autotask. This profile specifies the NetView Bridge command RTRINIT as the initial command that runs at task initialization time to start NetView Bridge.\n\nUsing the NetView-supplied sample DSIPROFE (CNMS1051), you can create a new profile by changing the existing PROFILE statement and naming it to the new profile name (prfname).\nThe syntax for this profile is:\n\n```\nprfname PROFILE IC=RTRINIT hqueue,rqueue,oqueue,hqueuel\n```\n\nNotes:\n1. For an explanation of the RTRINIT command and its syntax, see \"Appendix A. NetView Bridge Initialization Commands\" on page 87.\n2. Replace prfname with the profile name that you defined in Step 1.\n3. If you intend to use more than one autotask to communicate with the database servers, the positional queue names (hqueue, rqueue, oqueue) must be unique.\n\n**Step 3. Adding NetView Bridge Command Model Statements to the NetView Program**\n\nYou must define the NetView Bridge commands to the NetView program by using command model (CMDMDL) statements. In MVS, these statements are in the DSICMD member of the DSIPARM data set. The following CMDMDL statements are required on the resident NetView system:\n\n```\nRTRINIT CMDMDL MOD=DSINBINT,TYPE=R,RES=N\nRTRQUEUE CMDMDL MOD=DSINBQUE,TYPE=R,RES=Y\nTRANRCV CMDMDL MOD=DSINBRCV,TYPE=R,RES=Y\nTRANSND CMDMDL MOD=DSINBSND,TYPE=R,RES=Y\nDSINBRSM CMDMDL MOD=DSINBRSM,TYPE=R,RES=Y\nDSINBTRM CMDMDL MOD=DSINBTRM,TYPE=R,RES=Y\n```\n\nNote: If the NetView Bridge dispatcher is infrequently used, consider changing RES=Y to RES=N to save storage.\n\nThe RTRINIT command is described in \"Appendix A. NetView Bridge Initialization Commands\" on page 87, and the TRANRCV and TRANSND commands are described in \"Appendix B. NetView Bridge Requester API Commands and Service Routines\" on page 91. Commands RTRQUEUE, DSINBRSM, and DSINBTRM are internal NetView commands, and are not described.\n\n**Step 4. Creating a Server to Work with the NetView Program and Your Target Database**\n\nIf you have purchased a database server that allows you to create your own transactions, see the documentation provided with that database server and then proceed to \"Step 5. Creating a New Transaction Processor for an Existing Server\" on page 10.\n\nIf you have not purchased a database server, develop your server software based on the instructions given in \"Chapter 3. Creating a Database Server\" on page 15. As part of creating your own server, you complete the tasks outlined in \"Step 5. Creating a New Transaction Processor for an Existing Server\" on page 10. Therefore, after completing the instructions in \"Chapter 3. Creating a Database Server\" on page 15, you can resume these procedures beginning with \"Step 6. Creating NetView Command Procedures\" on page 10.\n\nCreating a new database server requires some programming effort. You must have an understanding of the server support API, and knowledge about accessing your target database. You can use either the PL/I or C programming language.\nStep 5. Creating a New Transaction Processor for an Existing Server\n\nAt this point, you need to decide whether you want to add new transactions to your database server. If you have decided not to create any new transactions, proceed to Step 6. Creating NetView Command Procedures.\n\nCreating a transaction processor requires some programming effort. You must understand the server support API, how to access your database server, and how to access your target database. You can use either the PL/I or C programming language.\n\nSee Creating a Transaction Processor on page 20 for information on creating a transaction processor.\n\nStep 6. Creating NetView Command Procedures\n\nFor this step, you need to do some programming in the language of your choice. The NetView Bridge Requester API supports the following languages:\n- C\n- NetView command list language\n- PL/I\n- REXX\n\nUsing the criteria outlined in Designing Functions in the Tivoli NetView for OS/390 Customization Guide, decide which programming language is most suitable for your needs. See Chapter 4. Writing a NetView Bridge Command Procedure Using the NetView Bridge Requestor API on page 53 for instructions on writing command procedures.\n\nStep 7. Determining Whether to Use Multiple Copies of a Database Server\n\nIf you anticipate a large amount of traffic crossing the bridge to a given database, you might want to employ multiple database servers to handle the workload. Multiple database servers distribute the load and can reduce the time it takes to process requests and replies.\n\nTo determine whether adding multiple database servers is the best way for you to improve performance, see Chapter 6. Adjusting NetView Bridge to Optimize Performance on page 83.\n\nThe procedure for creating multiple database servers depends upon the type of database servers you already have. Consult the documentation for your particular server for instructions on how to create multiple database servers.\n\nNetView Bridge requires minimal changes to accommodate additional servers. You must review queue sizes specified with the RTRINIT command in Step 2. Creating a NetView Bridge Dispatcher Profile on page 8 to ensure that you remain within your storage limitations. For additional details on setting queue limits, see Adjusting Queue Limits on page 84.\n\nStep 8. Assigning Queue Names to Database Servers\n\nYou must assign a unique program-to-program interface queue name for each copy of a server. This queue is used by the server to receive input from the NetView bridge dispatcher. Consult the documentation for your particular server for detailed instructions on how to identify this name to the server.\nCompleting the Initial Setup of NetView Bridge\n\nWhen you complete the setup of NetView Bridge, you can proceed to [Chapter 5, Starting NetView Bridge, a Database Server, and NetView Bridge Remote Access] on page 79 to ensure that you made all the necessary adjustments in setting up NetView Bridge.\n\nPreparing to Set Up Remote Access to NetView Bridge\n\nThe NetView Bridge remote dispatcher can be defined on any NetView program operating in an MVS, VM, or VSE environment. However, the NetView Bridge remote dispatcher must also be defined on the same MVS NetView system in which NetView Bridge is operating. Once you choose the NetView programs on which to activate the NetView Bridge remote dispatcher, you are ready to proceed with the setup steps on the following pages.\n\nNote: Do not bypass any of the steps in this section. Ensure that you complete each task within each step for all systems that will access NetView Bridge remotely.\n\nStep 1. Adding an Operator ID for the Remote Dispatcher Autotask\n\nAn operator ID for the NetView Bridge remote dispatcher autotask must be defined on both the resident MVS NetView system and the remote NetView system. Both the resident MVS host and the remote NetView system have an operator ID, REMOPER, that you can customize with your own unique operator ID and profile name (#prfname). This ID registers the NetView Bridge remote dispatcher as an management services (MS) application with the high performance transport API by executing the REMOTEBR command.\n\nNote: It is not recommended that you define the NetView Bridge remote dispatcher on your resident MVS NetView system to be the same autotask as the NetView Bridge dispatcher. Your bridge dispatcher autotasks should be exclusive to either the NetView Bridge dispatcher or the NetView Bridge remote dispatcher.\n\nTo define the IDs, you must modify the DSIOPF member of DSIPARM. For example, in the following OPERATOR statement, replace the highlighted name (REMOPER) with the unique operator ID that you have selected, and replace #prfname with the name of the profile that you have selected.\n\n```\nREMOPER OPERATOR PROFILEN=#prfname\n```\n\nThis change takes effect the next time you recycle the NetView program.\n\nStep 2. Creating a NetView Bridge Remote Dispatcher Profile\n\nYou must create a new member in the NetView DSIPRF data set in MVS, a new file with filetype NCCFLST on the RUN disk for VM, or a new sublibrary member in PRD2.SAxx for VSE. This new member or file should have the same name (#prfname) that you selected in Step 1 of your NetView Bridge remote access setup. It authorizes the operator to act as a NetView Bridge remote dispatcher autotask. This profile specifies the NetView Bridge command REMOTEBR as the initial command that runs at task initialization time to start NetView Bridge remote access.\n\nUsing the NetView-supplied sample DSIPROFF (CNMS1052), you can create a new profile by changing the existing PROFILE statement and naming it to the new profile name (#prfname).\nThe syntax for this profile is:\n\n```plaintext\nprfname PROFILE IC=REMOTEBR\n```\n\n**Notes:**\n\n1. For an explanation of the REMOTEBR command, see \"Appendix A. NetView Bridge Initialization Commands\" on page 87.\n2. Replace `prfname` with the profile name that you defined in Step 1.\n3. The autotask must have authority to issue the REMOTEBR command.\n\n### Step 3. Adding NetView Bridge Remote Access Command Model Statements to NetView\n\nYou must define the NetView Bridge remote access commands to the NetView program by using command model statements. These statements are in the DSICMD member of the DSIPARM data set in MVS, the CMS file DSICMD in VM, or the DSICMD member in the PRD2.SAxx sublibrary in VSE.\n\nTo access NetView Bridge remotely, you must define command model statements on both the resident NetView system and the remote NetView system.\n\n- **On the resident NetView system,** the following CMDMDL statements are required:\n\n ```plaintext\n RTRINIT CMDMDL MOD=DSINBINT,TYPE=R,RES=N\n RTRQUEUE CMDMDL MOD=DSINBQUE,TYPE=R,RES=Y\n TRANRCV CMDMDL MOD=DSINBRCV,TYPE=R,RES=Y\n TRANSND CMDMDL MOD=DSINBSND,TYPE=R,RES=Y\n DSINBRSM CMDMDL MOD=DSINBRSM,TYPE=R,RES=Y\n DSINBR62 CMDMDL MOD=DSINBR62,TYPE=R,PARSE=N,RES=Y\n REMOTEBR CMDMDL MOD=DSINBREM,TYPE=R,PARSE=Y,RES=N\n DSINBRLG CMDMDL MOD=DSINBRLG,TYPE=R,PARSE=Y,RES=Y\n ```\n\n **Note:** If the NetView Bridge dispatcher and remote dispatcher are infrequently used, consider changing RES=Y to RES=N to save storage. If only the remote dispatcher is infrequently used, consider changing RES=Y to RES=N on the DSINBR62 and DSINBRLG command model statements to save storage.\n\n- **The following CMDMDL statements are required on the remote NetView system:**\n\n ```plaintext\n TRANRCV CMDMDL MOD=DSINBRCV,TYPE=R,RES=Y\n TRANSND CMDMDL MOD=DSINBSND,TYPE=R,RES=Y\n DSINBR62 CMDMDL MOD=DSINBR62,TYPE=R,PARSE=N,RES=Y\n REMOTEBR CMDMDL MOD=DSINBREM,TYPE=R,PARSE=Y,RES=N\n DSINBRLG CMDMDL MOD=DSINBRLG,TYPE=R,PARSE=Y,RES=Y\n ```\n\n **Note:** If the remote dispatcher is infrequently used, consider changing RES=Y to RES=N to save storage.\n\nThe REMOTEBR command is described in \"Appendix A. NetView Bridge Initialization Commands\" on page 87, and the TRANRCV and TRANSND commands are described in \"Appendix B. NetView Bridge Requester API Commands and Service Routines\" on page 91. Commands DSINBR62 and DSINBRLG are internal NetView commands and are not described.\n\n### Step 4. Creating NetView Command Procedures\n\nFor this step, you need to do some programming in the language of your choice. The NetView Bridge Requester API supports the following languages operating in MVS, VM, and VSE:\n• C (MVS only)\n• NetView command list language (VM and VSE only)\n• PL/I (MVS only)\n• REXX (MVS and VM only)\n\nUsing the criteria outlined in the Tivoli NetView for OS/390 Customization Guide, decide which programming language is most suitable for your needs. See \"Chapter 4. Writing a NetView Bridge Command Procedure Using the NetView Bridge Requestor API\" on page 55 for instructions on writing command procedures.\nChapter 3. Creating a Database Server\n\nThis chapter documents general-use programming interface and associated guidance information.\n\nThis chapter describes some considerations and procedures for developing your own database server. Creating your own database server requires an understanding of concepts that are unique to NetView Bridge. Some of these concepts are:\n\n- Capturing return codes from the NetView Bridge server support API\n- Compiling and link-editing a database server\n- Creating database server control code using PL/I or C:\n - You should know how to request MVS system services from an assembler language program.\n - System programmer assistance is required to implement your database server in your MVS system because you need set up information, such as data set names.\n- Creating transaction processors using PL/I or C:\n - You should have expertise in developing application programs using HLL programming languages (PL/I or C)\n - You should have an understanding of how to access your intended target database.\n\nDocumenting Your Database Server\n\nSome procedures in this book direct you to documentation for your database server. If you have decided to create your own server, it is imperative that you document its flow and how it works, in detail.\n\nCoding a Database Server with the Server Support API Using PL/I\n\nThis section provides the necessary information for coding a database server with the server support API using PL/I. Figure 13 on page 25 provides an example for you to use as a model when creating your own PL/I program.\n\nRun-Time Options for PL/I\n\nThere are no restrictions on PL/I run-time options from the server support API.\n\nTypes of Parameters Passed to the Server Support API Service Routines for PL/I\n\nFour types of parameters can be passed to the server support API service routines. They are:\n\n- Pointer variables\n- Integer variables\n- Fixed-length character strings\n- Varying-length character strings\n\nThe server support API service routines require you to declare, initialize, and pass parameters to the API service routines according to PL/I programming language specifications. For more information on these specifications, refer to OS PL/I Version 2 Programming: Language Reference and Coding Your PL/I Program in Tivoli NetView for OS/390 Customization: Using PL/I and C.\nControl Blocks for PL/I\nA number of control blocks and include files are required for execution of your database server with the server support API service routines. You must include the NetView file DSIBPLI in your PL/I program. DSIBPLI includes the following files:\n\n**DSIBPHLB**\nRequired file that contains a PL/I mapping of the NetView Bridge HLL control block.\n\n**DSIBPHLS**\nRequired file that contains PL/I definitions for server support API service routines.\n\n**DSIBPCNM**\nOptional file that you can tailor to your needs. It declares return code constants for PL/I.\n\n**DSIPPRM**\nRequired file only for server support service routine CNMESTR. It contains a PL/I mapping of the transaction parameter block.\n\nReturn Codes for PL/I\nUpon completion of a server support API service routine, the return code from that service routine is stored in the return code field (HLBRC) of the control block DSIBPHLB. Your code must check this field after each API service routine invocation.\n\nCoding a Database Server with the Server Support API Using C\nThis section provides the necessary information for coding a database server with the server support API using C programming language. Figure 14 on page 42 provides an example for you to use as a model when creating your own C program.\n\nRun-Time Options for C\nThere are no restrictions on C run-time options from the server support API.\n\nTypes of Parameters Passed to the Server Support API Service Routines for C\nFour types of parameters can be passed to the server support API service routines. They are:\n- Pointer variables\n- Integer variables\n- Fixed-length character strings\n- Varying-length character strings\n\nDeclare, initialize, and pass parameters to the API service routines according to C programming language specifications. For more information on these specifications, refer to *SAA®: Common Programming Interface C Reference* and *Coding Your PL/I Program: Environment, Interfaces, and Restrictions* in *Tivoli NetView for OS/390 Customization: Using PL/I and C*.\n\nControl Blocks for C\nA number of control blocks and include files are required for execution of your C program with the server support API service routines. You must include the NetView file DSIBC in your C program. DSIBC includes the following files:\n**DSIBCHLB**\nRequired file that contains a C mapping of the NetView Bridge HLL control block.\n\n**DSIBCCAL**\nRequired file that contains C definitions for server support API service routines.\n\n**DSIBCCNM**\nOptional file that you can tailor to your needs. It declares return code constants for C.\n\n**DSICPRM**\nRequired file only for server support service routine CNMESTR. It contains a C mapping of the transaction parameter block.\n\n**DSICVARC**\nOptional file that contains a C mapping of a varying-length character string.\n\n### Return Codes for C\n\nUpon completion of a server support API service routine, the return code from that service routine is stored in the return code field (HLBRC) of the control block DSIBCHLB. Your code must check this field after each API service routine invocation.\n\n### Creating Database Server Control Code\n\nThis section describes the procedures for creating your own database server control code. The database server control code must initialize the database server and repeat the following steps as necessary:\n\n1. Wait for a NetView Bridge transaction request\n2. Invoke the appropriate transaction processor when a transaction request is received.\n\nThis code must also terminate the database server, when appropriate.\n\n### Initializing the Database Server\n\nYour code must initialize the database server by performing the following procedures:\n\n- Open any necessary files. For example, you might need to open or access logging files, initialization parameter files, or files related to your target database.\n- Establish a mechanism for recognizing when an MVS operator wants to stop your database server. One method for doing this is to code your server to recognize the MVS STOP command. This provides for an orderly termination process for your database server with NetView Bridge.\n- Initialize the NetView Bridge server support API by calling the CNMETIN service routine.\n\n**CNMETIN** performs the following functions:\n\n- Defines the environment by establishing the *bhlbptr* parameter used by all of the other server support API service routines.\n- Initializes the server support API by defining your program-to-program interface (PPI) input queue. The name for the input queue is defined by the *tiinq* parameter of CNMETIN.\nNotes:\n\n1. If you intend to use multiple servers, the name that you assign to `tiinq` must be unique for each copy of a database server.\n\n2. The limit for queued transactions is defined by the `tiinqlim` operand of CNMETIN. You must assign queue limits for your database servers. Select an adequate queue size to avoid a problem with the queue filling up during database server operations. This number should be approximately four times the number of concurrent ready tokens that can be pending for this database server. The number of concurrent ready tokens that can be pending for this database server depends on the number specified on the `rqueue` parameter of RTRINIT.\n\n - Identifies the program-to-program interface (PPI) queue for communication to the NetView program. The name for this output queue is defined by the `tioutq` operand of CNMETIN. This name must be identical to the name specified with the `oqueue` operand of the NetView Bridge command RTRINIT.\n\nNote: All nonzero CNMETIN return codes should be treated as catastrophic failures. In particular, return code (RET_PPI_FAILURE +16) is generated if you attempt to initialize a database server that is already started.\n\n- You might have to initialize your target database interface. You must be familiar with the interface requirements of your target database. Consult any available documentation for your database and create the necessary code for initializing it, if required.\n\nControlling Flow\n\nThe control code must control the flow of data between your database server and the NetView program. Establishing control of this interface involves several considerations. These are described in the following sections.\n\nSending Ready Tokens\n\nSome database interfaces can support multitasking. If this is the case at your installation, your database server can send multiple ready tokens. Consult any available documentation for your database interface for information on its limitations on multitasking.\n\nYou might consider receiving and processing any transaction requests in the PPI queue `tiinq`. Before your code issues any ready tokens, these transaction requests should be passed to the appropriate transaction processors.\n\nYour code must call the NetView Bridge server support API CNMERTR service routine once for each transaction that can be processed concurrently. (If your database interface does not allow concurrent transactions, CNMERTR needs to be called only once.) This routine sends a ready token to NetView Bridge.\n\nWhen it receives a ready token indicating that this copy is ready to process a transaction, NetView Bridge sends a transaction to this copy of your database server.\n\nReceiving a Queued Transaction\n\nTo receive the next transaction in the input queue, you must call the CNMENTR service routine. CNMENTR attempts to retrieve the next transaction. If no transaction is found in the input queue, return code RET_NOT_FOUND is issued, and you need to enter a wait state.\n**Waiting for a Transaction**\nTo enter a wait state after an unsuccessful attempt to get the next transaction, your code must call the NetView Bridge CNMEWAT service routine. In addition to waiting for a transaction to be placed on the input queue, CNMEWAT can also wait for events specific to your server (for example, the MVS operator command STOP).\n\nYour code can set the WAECBP parameter of service routine CNMEWAT to the address of a standard event control block (ECB) list to wait for user-defined events. If you do not want to wait for any user-defined events, set parameter WAECBP to a PL/I or C null. For an example of an assembler language source code that you can use to obtain the address of a communications ECB, see Figure 15 on page 52.\n\n**Note:** Parameter WAECBP must be set to either an ECB address or a PL/I or C null. When an awaited event is posted, CNMEWAT issues one of two return codes:\n- **RET_WAIT_POSTED (RC=12)**\n This return code means that one or more of the user-provided ECBs were posted, and that there is no transaction in the input queue. You are responsible for handling the processing of your ECBs.\n- **RET_WAIT_POSTED_PPI (RC=8)**\n This return code means that at least one transaction is in the input queue. One or more of the user-provided ECBs might be posted.\n\nIf you have established a mechanism to recognize that the MVS operator wants to stop the server, you should call the CNMETQU service routine to send a CNMQUISE transaction to the NetView Bridge dispatcher. This removes all ready tokens related to this database server. When the dispatcher completes this task, it sends the CNMQUISE transaction back to the database server to indicate that the quiesce state is in effect.\n\n**Obtaining a Transaction Identifier**\nOnce CNMENTR successfully retrieves a transaction, your code can call the CNMEGTP service routine to determine what transaction was received.\n\nCNMEGTP can retrieve many parameters. At this point, however, you need to use it only to identify the transaction that was received. For this identification to take place, call CNMEGTP with its parameters set as follows:\n- The `gpmethod` parameter must have a value of H (meaning this is a header parameter).\n- The `gpnameh` parameter must have a value of TRANSID (meaning that you want it to return the transaction identifier).\n- The `gpdatlen` parameter must contain the size of the data buffer that receives the name of this transaction. The value of this parameter must be at least 8.\n- The `gpdata` parameter must be a varying-length character field that is used to receive the incoming transaction ID.\n\n**Invoking the Appropriate Transaction Processor**\nUsing the transaction identifier that you received, invoke the appropriate transaction processor for your database server.\n\nAfter the transaction processor completes its work, your code must call the CNMERTR service routine to inform the NetView Bridge dispatcher that you are ready to process another transaction. Your code must then return to receive the next transaction (see [Receiving a Queued Transaction](#) on page 18).\nIf the transaction identifier is CNMQUISE, the NetView Bridge dispatcher removes all ready tokens, and the database server does not receive any more transactions. After the last transaction completes processing, you should invoke the termination process described in \"Terminating the Database Server\".\n\n**Terminating the Database Server**\n\nBecause all transaction processing is complete, your code must perform the following:\n\n- Call the NetView Bridge server support API CNMETRM service routine to terminate the NetView Bridge server support API.\n- Terminate your database interface, as required by your database.\n- Close all data sets.\n- Issue a message to the MVS system console indicating that this server is terminating.\n\n**Creating a Transaction Processor**\n\nThis section describes how to create a transaction processor to work between the NetView Bridge server support API and your target database.\n\nAfter you design the transaction, you can develop the transaction processor. Your transaction processor must be written to accept a transaction request from the server support API. The processor must then extract the input parameters from the transaction request and use them to interact with the interface to your target database.\n\nOnce the transaction request is satisfied by the target database, your transaction processor must process the results and convert them to the format required by the server support API. Your transaction processor might then pass the transaction reply to the server support API, if a reply was requested.\n\n**Designing the Transaction**\n\nBefore you create a transaction processor, you must make some basic design decisions. These decisions include:\n\n- Defining the function of the transaction\n- Deciding what input parameters are required by the transaction processor and the target database\n- Deciding what needs to be returned in the transaction reply\n\nEnsure that you are familiar with language restrictions pertaining to the NetView Bridge command procedures that are requesting the services of your transaction processor. In particular, NetView command list language parameters cannot exceed 11 characters, and this language has no provisions for array processing. For more information on the NetView command list language, refer to [Tivoli NetView for OS/390 Customization: Using REXX and the NetView Command List Language](#).\n\n**Processing the Transaction Request**\n\nTo extract the input parameters from the transaction request, you must do two things:\n\n1. Write the code to extract header parameters (method H) using the NetView Bridge server support API CNMEGTP service routine. (Methods for retrieving parameters are described in “CNMEGTP (CNMETRPARM) Service\".)\nExtract the following header parameters for use in generating the reply:\n- TRANSID (transaction ID)\n- ORIGNET (originating network ID)\n- ORIGDOM (originating domain ID)\n- ORIGTASK (originating task ID)\n- DESTNET (destination network ID)\n- DESTDOM (destination domain ID)\n- DESTTASK (destination task ID)\n- TRTYPE (type of transaction)\n- CORR (correlator)\n- VOCAB (vocabulary)\n\n2. Write the code to extract the transaction parameter (method N or P) information using the NetView Bridge server support API CNMEGTP service routine. See \"CNMEGTP (CNMETRPARM) Service Routine—Get Transaction Request Parameters\" on page 107 for details on how to use this service routine.\n\nInteracting with the Database Interface\n\nWrite code that sends the transaction request to the target database interface. You must ensure that the data you forward meets any special requirements of your target database. Consult the documentation for your target database for any such requirements.\n\nOnce the transaction request is forwarded to the database interface and the request is satisfied, your transaction processor must process the results in preparation for conversion and forwarding to the NetView Bridge server support API.\n\nSetting Up the Transaction Parameter Blocks\n\nThe NetView program contains a parameter block structure specifically for use with the NetView Bridge server support API CNMESTR (send a transaction reply) service routine. The parameter block structure has two separate versions—one for PL/I (DSIPPRM), and one for C (DSICPRM).\n\nWhen you write the code to initialize your parameters, place each nonheader parameter in its own allocated copy of the parameter block structure. Your code must store the required information in this parameter block structure.\n\nFinally, write code to link these parameter block structures together for use by the CNMESTR service routine. To do this, set the pointer field (PRMLINK) in each parameter block to the next parameter block. The final parameter block should point to null. This links the parameter blocks together, as shown in Figure 8.\n\n\nForwarding the Transaction Reply\n\nNow, create the code to forward the data (the transaction reply) back to the NetView program using the server support API. This code must perform the following tasks:\n\n- Examine the value of the `trtype` parameter that was extracted from the original transaction request. The `trtype` must contain one of the following three values:\n - QNON—No reply is to be sent.\n - QERR—Reply is sent only if errors have occurred during processing.\n - QALL—All data is to be returned.\n\n- Call the NetView Bridge server support API CNMESTR service routine to send the transaction reply to the NetView requestor if a reply is to be sent (`trtype` of QERR or QALL).\n\nYour call to CNMESTR must contain several header operands. Table 4 lists these operands and their sources.\n\nTable 4. Header Operands Required for the CNMESTR Service Routine\n\n<table>\n<thead>\n<tr>\n<th>CNMESTR Operands</th>\n<th>Source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>transid</td>\n<td>transid operand of the transaction request</td>\n</tr>\n<tr>\n<td>trtype</td>\n<td>RPLY</td>\n</tr>\n<tr>\n<td>destnet</td>\n<td>orignet operand of the transaction request</td>\n</tr>\n<tr>\n<td>destdom</td>\n<td>origdom operand of the transaction request</td>\n</tr>\n<tr>\n<td>desttask</td>\n<td>origtask operand of the transaction request</td>\n</tr>\n<tr>\n<td>orignet</td>\n<td>destnet operand of the transaction request</td>\n</tr>\n<tr>\n<td>origdom</td>\n<td>destdom operand of the transaction request</td>\n</tr>\n<tr>\n<td>origtask</td>\n<td>desttask operand of the transaction request</td>\n</tr>\n<tr>\n<td>vocab</td>\n<td>Can be the vocab operand of the transaction request (only used if your database server supports this function)</td>\n</tr>\n<tr>\n<td>corr</td>\n<td>corr operand of the transaction request</td>\n</tr>\n<tr>\n<td>respcode</td>\n<td>Code generated by the transaction processor that summarizes the results of the processed transaction</td>\n</tr>\n<tr>\n<td>parms</td>\n<td>Pointer to the first transaction parameter block in the linked list</td>\n</tr>\n</tbody>\n</table>\n\nOnce you have created the code to perform the tasks outlined in this section, your transaction processor is complete.\n\nCompiling and Link-Editing a Database Server with the Server Support API in PL/I\n\nThis section describes the procedures for compiling and link-editing your database server written in PL/I with the NetView Bridge server support API.\n\nCompiling Considerations for PL/I\n\nThe recommended compile-time options for the NetView Bridge server support API are MACRO, LIST, and OBJECT. You must include SYS1.MACLIB in the SYSLIB statement of the compiled job control language (JCL). An example of the compile-step JCL for PL/I is shown in Figure 9.\nLink-Editing Considerations for PL/I\n\nThe following rules apply to link-editing PL/I database server modules with the NetView Bridge server support API modules:\n\n- PL/I load modules can reside in either 24- or 31-bit storage and can be entered in either addressing mode.\n- You must link-edit your PL/I load modules with the CNMETIN and CNMETRM load modules provided by the NetView program in SYS1.LINKLIB.\n- Include SYS1.LINKLIB in the SYSLIB statement in the PL/I link-edit step of the JCL.\n\nAn example of the link-edit step of the JCL for PL/I is shown in Figure 10.\n\nCompiling and Link-Editing a Database Server with the Server Support API in C\n\nThis section describes the procedures for compiling and link-editing your database server written in C with the NetView Bridge server support API.\n\nCompiling Considerations for C\n\nInclude SYS1.MACLIB in the SYSLIB statement of the compiled JCL. An example of the compile-step JCL for C is shown in Figure 11.\nLink-Editing Considerations for C\n\nThe following rules apply for link-editing C database server modules with the NetView Bridge server support API modules:\n\n- C load modules can reside in either 24- or 31-bit storage and can be entered in either addressing mode.\n- Link-edit your C load modules with the CNMETIN and CNMETRM load modules provided by the NetView program in SYS1.LINKLIB.\n- Include SYS1.LINKLIB in the SYSLIB statement in the C link-edit step of the JCL.\n\nAn example of the link-edit step of the JCL for C is shown in Figure 12.\n\n```\n//COMPILE EXEC PGM=EDCCOMP,REGION=®SIZ\n\n//SYSLIB DD DSN=SYS1.MACLIB,DISP=SHR\n```\n\nFigure 11. Example of a Compile Step JCL for the Server Support API in C\n\n```\n//LKED EXEC PGM=IEWL,\n// PARM='XREF,RENT,LET,LIST',\n// REGION=4096K,COND=(8,LE,COMPILE)\n\n//SYSLIB DD DSN=SYS1.V1R1M1.SEDCBASE,DISP=SHR\n// DD DSN=SYS1.V2R2M0.SIBMBASE,DISP=SHR\n// DD DSN=SYS1.LINKLIB,DISP=SHR\n\nINCLUDE SYSLIB(CNMETIN)\n\nINCLUDE SYSLIB(CNMETRM)\nENTRY CEESTART\nMODE AMODE(31),RMODE(ANY)\nNAME DBSERVER(R)\n```\n\nFigure 12. Example of a Link-Edit Step JCL for the Server Support API in C\n\nExample PL/I Program Using the Server Support API\n\nFigure 13 on page 25 is an example of a PL/I program that uses the server support API. You can use this as a model for creating your own PL/I program.\nSERTRAN: PROC OPTIONS(MAIN);\n/\n* Sample PL/I program using the Server Support API. *\n/\n/**************************\n/* Include files section */\n/* DSIBPLI will include the following files: */\n/* DSIBPLI - PL/I mapping of HLB */\n/* DSIBPHLS - PL/I definition for Server Support API routines */\n/* DSIBPCNM - Return codes */\n/* DSIPPRM - PL/I mapping of transaction parameter block */\n*************************/\n%INCLUDE DSIBPLI;\n/\n/**************************\n/* External module declaration */\n**************************/\nDCL GETECB ENTRY (PTR,CHAR(8));\n/\n/* Constants */\n/\nDCL EBCDIC_TYPE BIT(16) INIT('0000000011101110'B);\nDCL BIN_TYPE BIT(16) INIT('0000000010111011'B);\nDCL NOT_AN_INDEX FIXED BIN(31,0) INIT(-32767);\n/\n/**************************\n/* Variables used to call CNMETIN service routine */\n**************************/\nDCL TIINQ_NAME CHAR(8) INIT('SERINQ');\n /* Server input queue */\nDCL TIOUTQ_NAME CHAR(8) INIT('OQUEUE');\n /* Server output queue */\nDCL TIINQ_LIMIT FIXED BIN(31,0) INIT(4);\n/\n/**************************\n/* Variables used to call CNMEGTP service routine */\n**************************/\nDCL GPMETHOD CHAR(1);\nDCL GPNAMEH CHAR(8);\nDCL GPNAMEP CHAR(31) VARYING;\nDCL GPINDEX FIXED BIN(31,0) INIT(NOT_AN_INDEX);\nDCL GPDATA CHAR(256) VARYING;\nDCL GPDATLEN FIXED BIN(31,0);\nDCL GPTYPE CHAR(2) INIT(EBCDIC_TYPE);\nDCL GPCURSOR FIXED BIN(31,0);\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 1 of 17)\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 2 of 17)\n/* Initialization of your database interface. NOT shown here */\n\nCALL CNMETIN (BHLBPTR, /* To define the environment */\n TIINQ_NAME, /* Input queue name */\n TIINQ_LIMIT, /* Limit queued transactions */\n TIOUTQ_NAME); /* Output queue name */\n\nIF (HLBRC = RET_GOOD) THEN /* Initialization is successful */\n DO;\n\n /* Clean up the input queue by reading and discarding all */\n /* outstanding transactions in the input queue. Processing of */\n /* outstanding transactions and error handling are NOT shown */\n /* here. */\n\n DO WHILE ((HLBRC = RET_GOOD) & (¬EMPTYQ));\n CALL CNMENTR (BHLBPTR);\n IF (HLBRC = RET_NOT_FOUND) THEN\n EMPTYQ = '1'B;\n END;\n END;\n\n /* The input queue is now empty. Prepare the Event Control */\n /* Block (ECB) list to be used later when calling CNMEWAT. */\n /* 1. Call GETECB to get the pointer to the communication */\n /* ECB and the job name of the database server. */\n /* (See the assembler example GETECB in this document.) */\n /* 2. Turn the first bit of the pointer to the communication */\n /* ECB list to 1 to indicate the end of the CECB list. */\n /* 3. Get the address of the pointer to CECB for use later by */\n /* CNMEWAT. */\n\n IF EMPTYQ THEN\n DO; /* If input queue is empty */\n CALL GETECB(CECB_PTR,JOB_NAME);\n CECB_BIT_FORM(1) = '1'B;\n WAECBP = ADDR(CECB_PTR);\n END;\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 3 of 17)\nDo the following process until terminated:\n\n1. Send a READY token\n2. Wait for ECB list to be posted\n3. Wake up when ECB list is posted to either:\n i) process a transaction OR\n ii) send the QUIESCE token when ECB is terminated\n\nCALL CNMERTR (BHLBPTR); /* Send a READY token */\nIF (HLBRC = RET_GOOD) THEN\n DO UNTIL (TERMINATED);\n CALL CNMEWAT (BHLBPTR,WAECBP); /* Wait for the ECB list */\n END;\n /* Wake up to check which ECB is posted */\n SELECT (HLBRC);\n WHEN (RET_WAIT_POSTED_PPI)\n DO;\n /* Either PPI ECB or User ECB (STOP command is entered) is posted. If User ECB is posted, send a QUIESCE token and process all transactions in the input queue. Only send READY token when it is not User ECB posted. */\n IF (SUBSTR(UNSPEC(CECB_PTR -> ECB),2,1) = '1') THEN\n /* User ECB is posted */\n USRECB_POSTED = '1';\n CALL CNMETQU (BHLBPTR);\n END;\n CALL PROCESS_TRANSACTION;\n END;\n END;\n END;\n CALL PROCESS_TRANSACTION;\n IF (~ USRECB_POSTED) THEN\n /* Send a READY token ONLY if the user ECB is NOT posted. */\n CALL CNMERTR (BHLBPTR);\n END;\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 4 of 17)\nWHEN (RET_WAIT_POSTED)\n DO;\n /* Operator has entered the STOP command which */\n /* caused this ECB to be posted. Send a QUIESCE */\n /* token. */\n CALL CNMETQU (BHLBPTR);\nEND;\n\nOTHERWISE;\n CALL CNMETQU (BHLBPTR);\n END; /* SELECT on HLBRC */\n END; /* Do until TERMINATED */\n END; /* If input queue is empty */\n END; /* Initialization is successful */\nEND; /* Initialization of NetView Bridge Server is not successful */\nELSE\n DO;\n /* Error processing NOT shown */\n END;\nEND;\n\n/* PROCESS_TRANSACTION procedure */\n/* Process all transactions in the input queue. This procedure */\n/* is intended only as an example of how to process transactions */\n/* in the input queue. Four other procedures will be called from */\n/* here: */\n/* 1. GET_HEADER: to illustrate how to obtain all header */\n/* information */\n/* 2. GET_NEXT: to illustrate how to use CNMEGTP to get the */\n/* next parameter in the parameter list */\n/* 3. GET_NAME: to illustrate how to use CNMEGTP to get the */\n/* value of a parameter by name */\n/* 4. SEND_REPLY: to illustrate how to use CNMESTR to send a */\n/* reply to the NetView requester */\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 5 of 17)\nPROCESS_TRANSACTION: PROC;\n\nDO WHILE (HLBRC = RET_GOOD);\n CALL CNMENTR(BHLBPTR); /* Get a transaction */\n\n SELECT (HLBRC);\n WHEN (RET_GOOD)\n DO;\n CALL GET_HEADER;\n IF (((HLBRC = RET_GOOD) & (~TERMINATED))) THEN\n DO;\n CALL GET_NEXT;\n IF (HLBRC = RET_GOOD) THEN\n DO;\n CALL GET_NAME;\n IF (HLBRC = RET_GOOD) THEN\n CALL SEND_REPLY;\n END;\n END;\n END;\n END;\n END;\n OTHERWISE;\n END; /* SELECT on HLBRC */\nEND; /* Do while */\nEND PROCESS_TRANSACTION;\n\n/******************************************************************************/\n/* GET_HEADER procedure */\n/* This procedure is intended only as an example of how to use */\n/* the CNMEGTP service routine with GPMETHOD = 'H' (to get the */\n/* header parameters of a transaction. */\n/* */\n/* Header parameters are: */\n/* */\n/* - ORIGNET - Origin network identifier */\n/* - ORIGDOM - Origin domain name */\n/* - ORIGTASK - Origin task name */\n/* - DESTNET - Destination network identifier */\n/* - DESTDOM - Destination domain name */\n/* - DESTTASK - Destination task name */\n/* - TRANSID - Transaction identifier */\n/* - TRTYPE - Transaction type */\n/* - VOCAB - Vocabulary, user specific */\n/* - CORR - Correlator, user specific */\n/* */\n/* The following parameters of CNMEGTP: GPNAMEP, GINDEX and */\n/* GPCURSOR are NOT used when getting header parameters. As a */\n/* result, they will NOT be initialized. */\n/******************************************************************************/\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 6 of 17)\nGET_HEADER: PROC;\n\n/**************************************************************************\n/* Local variables */\n/**************************************************************************\nDCL HDR_COUNT BIN(31); /* Header counter */\nDCL ORIGIN_TASK_NAME CHAR(8);\nDCL TRANSID_NAME CHAR(8);\n\n/**************************************************************************\n/* Procedure starts here */\n**************************************************************************\nGPMETHOD = 'H';\nHDR_COUNT= 1;\nDO WHILE ((HLBRC = RET_GOOD) &\n (HDR_COUNT <= 10) &\n (~TERMINATED));\n SELECT (HDR_COUNT);\n WHEN (1) GPNAMEH = 'ORIGNET';\n WHEN (2) GPNAMEH = 'ORIGTASK';\n WHEN (3) GPNAMEH = 'ORIGDOM';\n WHEN (4) GPNAMEH = 'DESTNET';\n WHEN (5) GPNAMEH = 'DESTTASK';\n WHEN (6) GPNAMEH = 'DESTDOM';\n WHEN (7) GPNAMEH = 'TRANSID';\n WHEN (8) GPNAMEH = 'VOCAB';\n WHEN (9) GPNAMEH = 'CORR';\n WHEN (10) GPNAMEH = 'TRTYPE';\n OTHERWISE;\n END;\n\n**************************************************************************\n/* Call CNMEGTP to get the header */\n**************************************************************************\nCALL CNMEGTP(BHLBPTR, /* to define the environment */\n GPMETHOD, /* retrieve header parameter */\n GPNAMEH, /* header name */\n GPINDEX, /* not use in this case */\n GPDATA, /* output header value */\n GPDATLEN, /* output header length */\n GPTYPE, /* not use in this case */\n GPCURSOR); /* not used in this case */\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 7 of 17)\nIF (HLBRC = RET_GOOD) THEN\n SELECT (HDR_COUNT);\n WHEN (2) DO;\n /**********************************************************************/\n /* Save the origin task name for later use (to determine */\n /* if a quiesce token was received) */\n /**********************************************************************/\n ORIGIN_TASK_NAME = SUBSTR(GPDATA,1,BHLBPTR -> HLBLENG);\n END;\n\n WHEN (7) DO;\n TRANSID_NAME = SUBSTR(GPDATA,1,BHLBPTR -> HLBLENG);\n SELECT (TRANSID_NAME);\n WHEN ('CREATE') DO;\n /**********************************************************************/\n /* Call the appropriate routine to create a */\n /* record in the target database */\n /**********************************************************************/\n END;\n\n WHEN ('SEARCH') DO;\n /**********************************************************************/\n /* Call the appropriate routine to search for a */\n /* particular record in the target database */\n /**********************************************************************/\n END;\n\n WHEN ('UPDATE') DO;\n /**********************************************************************/\n /* Call the appropriate routine to update a */\n /* record in the target database */\n /**********************************************************************/\n END;\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 8 of 17)\nWHEN ('CNMQUISE')\n DO;\n IF (ORIGIN_TASK_NAME = TIINQ_NAME) THEN\n DO;\n TERMINATED = '1'B;\n CALL CNMETRM (BHLBPTR);\n END;\n END;\n OTHERWISE;\n END; /* Select on TRANSID_NAME */\n END;\nEND; /* Select on HDR_COUNT */\n\nWHEN (10)\n DO;\n /* Save the transaction type to be used later. */\n /* Increment HDR_COUNT to continue the loop */\n HDR_COUNT = HDR_COUNT + 1;\n END;\nEND GET_HEADER;\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 9 of 17)\n```c\n/* GET_NEXT procedure */\n/* This procedure is intended only as an example of how to use */\n/* the CNMEGTP service routine with GPMETHOD = 'N' (to retrieve */\n/* the name and value of the next transaction parameter) starting */\n/* the search process from GPCURSOR. */\n/* Parameters for call to CNMEGTP: */\n/* GPMETHOD = 'N' Input parameter */\n/* GPCURSOR = 0 indicates that the search process is to begin */\n/* at the start point of the parameter list. */\n/* Otherwise, the search process is determined */\n/* by GPCURSOR. This is an input parameter to */\n/* CNMEGTP. Users shall NOT modify this */\n/* parameter. */\n/* GPNAMEP Output parameter to contain the name of the */\n/* transaction parameter. */\n/* GINDEX Output parameter to indicate whether the */\n/* parameter is an element of an array. It's */\n/* value will be -32767 if NOT an element of an */\n/* array. */\n/* GPDATA Output parameter to contain the value of the */\n/* transaction parameter being retrieved. */\n/* GPDATLEN Input parameter. It specifies the length of */\n/* GPDATA (in bytes). The actual length of the */\n/* data returned in GPDATA will be stored in */\n/* HLBLENG. */\n/* GTYPE Output parameter that specifies the type of */\n/* the transaction parameter. Its value will be */\n/* either '00EE' or '00BB'. */\n/* The following parameter of CNMEGTP: GPNAMEH is not used when */\n/* retrieving the next parameter. As a result it will NOT be */\n/* initialized here. */\n```\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 10 of 17)\nGET_NEXT: PROC;\n\n/***************************************************************************/\n/* Initialize input parameters to CNMEGTP. */\n/***************************************************************************/\nGPCURSOR = 0; /* Indicate that search is to start */\n/* at the beginning of the list */\nGPMETHOD = 'N';\nGPDATLEN = 256; /* Since GPDATA is defined as */\n/* CHAR(256) VARYING */\n\nDO WHILE ( (HLBRC = RET_GOOD) |\n (HLBRC = RET_DATA_TRUNC));/* output value is truncated */\nCALL CNMEGTP (BHLBPTR,\n GPMETHOD,\n GPNAMEH,\n GPNAMEP,\n GPINDEX,\n GPDATA,\n GPDATLEN,\n GPTYPE,\n GPCURSOR);\n\n/***************************************************************************/\n/* Process the output -- This is only a skeleton. The */\n/* following procedures will be specific to your database */\n/* server. Those return codes that are NOT mentioned below, */\n/* are unlikely to occur. */\n/***************************************************************************/\nSELECT (HLBRC);\nWHEN (RET_GOOD)\nDO;\n\nWHEN (RET_END_FILE)\nDO;\n\nWHEN (RET_BAD_LENGTH)\nDO;\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 11 of 17)\nWHEN (RET_BAD_CURSOR)\nDO;\n/**************************************************************************/\n/* Re-check GPCURSOR. GPCURSOR should never be altered */\n/* by the user. */\n/**************************************************************************/\nEND;\n\nWHEN (RET_BAD_METHOD)\nDO;\n/**************************************************************************/\n/* Re-check GPMETHOD. Valid values are 'H', 'P' and 'N'. */\n/**************************************************************************/\nEND;\n\nWHEN (RET_DATA_TRUNC)\nDO;\n/**************************************************************************/\n/* GPDATA is NOT large enough to contain the value of the */\n/* transaction parameter. */\n/* */\n/* * GPCURSOR is updated to point to the next parameter. */\n/* */\n/* * If the user wishes to retrieve the current truncated */\n/* * parameter value again, he/she is recommended to follow */\n/* * these steps: */\n/* */\n/* * 1. Save the name of the parameter and its index, */\n/* * GPNAMEP and GPINDEX, respectively. Do NOT alter */\n/* * GPCURSOR. It will be used later. */\n/* */\n/* * 2. Allocate more space for GPDATA. The additional */\n/* * amount of space is equal to the difference */\n/* * between HLBLENG and GPDATLEN. */\n/* */\n/* * 3. Update GPDATLEN to reflect GPDATA's new size. */\n/* */\n/* * 4. Call CNMEGTP with GPMETHOD of 'P' with the saved */\n/* * values for GPNAMEP and GPINDEX (Step 1). */\n/* */\n/* * 5. Check the output as usual. */\n/* */\n/* * 6. Continue to call CNMEGTP with GPMETHOD of 'N' and */\n/* * the unaltered GPCURSOR (from the previous call to */\n/* * get next parameter) until there are no more */\n/* * parameters to receive. */\n/**************************************************************************/\nEND;\n\nEND; /* Select on HLBRC */\nEND; /* Do while HLBRC = RET_GOOD ... */\nEND GET_NEXT;\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 12 of 17)\nThis procedure is intended only as an example of how to use the CNMEGTP service routine with GPMETHOD = 'P' (to retrieve the value of a transaction parameter) when its name is known.\n\nParameters for call to CNMEGTP:\n\n- **GPMETHOD** = 'P' Input parameter. It contains the name of the parameter whose value is retrieved.\n- **GPNAMEP** Input parameter. It indicates whether or not the name specified by GPNAMEP is an element of an array. Its value will be -32767 if NOT an element of an array.\n- **GPINDEX** Input parameter. It contains the value of the transaction parameter being retrieved.\n- **GPDATA** Output parameter to contain the value of the transaction parameter.\n- **GPDATLEN** Input parameter. It specifies the length of GPDATA (in bytes). The actual length of the data returned in GPDATA will be stored in HLBLENG.\n- **GPTYPE** Output parameter that specifies the type of the transaction parameter. Its value will be either '00EE'X or '00BB'X.\n\nThe following parameters of CNMEGTP: GPCURSOR and GPNAMEH are not used when getting parameter by name. As a result, they will NOT be initialized here.\nCALL CNMEGTP (BHLBPTR,\nGPMETHOD,\nGPNAMEH,\nGPNAMEP,\nGPINDEX,\nGPDATA,\nGPDATLEN,\nGPTYPE,\nGPCURSOR);\n\n/***************************************************************************/\n/* Process the output -- This is only a skeleton. Those return */\n/* codes that are NOT mentioned below, are unlikely to occur. */\n/***************************************************************************/\nSELECT (HLBRC);\nWHEN (RET_GOOD)\nDO;\n /***********************************************************************/\n /* Successful retrieval of transaction parameter */\n /***********************************************************************/\nEND;\n\nWHEN (RET_BAD_LENGTH)\nDO;\n /***********************************************************************/\n /* Re-check GPDATLEN */\n /***********************************************************************/\nEND;\n\nWHEN (RET_BAD_NAME)\nDO;\n /***********************************************************************/\n /* The name specified in GPNAMEP and its index does not */\n /* exist in the parameter list. */\n /***********************************************************************/\nEND;\n\nWHEN (RET_NO_DATA)\nDO;\n /***********************************************************************/\n /* The name specified by GPNAMEP and its index exists in */\n /* the parameter list with no value. */\n /***********************************************************************/\nEND;\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 14 of 17)\nWHEN (RET_BAD_METHOD)\nDO;\n/**************************\n/* Re-check GPMETHOD. Valid values are 'H', 'P' and 'N'. */\n/**************************\nEND;\n\nWHEN (RET_DATA_TRUNC)\nDO:\n/**************************\n/* GPDATA is not large enough to contain the value of the */\n/* transaction parameter. */\n/* */\n/* If user wishes to retrieve the current truncated */\n/* parameter value again, he/she must perform the following */\n/* steps: */\n/* */\n/* 1. Save the name of the parameter and its index, GPNAMEP */\n/* and and GPINDEX respectively. */\n/* 2. Allocate more space for GPDATA. The additional */\n/* amount of space needed is equal to the difference */\n/* between HLBLENG and GPDATLEN. */\n/* 3. Update GPDATLEN to reflect GPDATA's new length. */\n/* 4. Call CNMEGTP, with GPMETHOD of 'P' with the saved */\n/* GPNAMEP and GPINDEX (from step 1). */\n/* 5. Process the output as usual. */\n/**************************\nEND;\nEND; /* Select on HLBRC */\nEND GET_NAME;\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 15 of 17)\n/* SEND_REPLY procedure */\n/* This procedure illustrates the correct process for sending a */\n/* reply to the NetView requester using the CNMESTR service routine.*/\n/* */\n/* 1. Interchange the following parameters to reflect the correct */\n/* sender and receiver: Orignet, Origdom, Origtask and Destnet, */\n/* Destdom, Desttask. This swapping of destination and origin */\n/* parameters will NOT be shown here. */\n/* */\n/* 2. If the TRTYPE (received from the request) is QALL, a reply */\n/* must be sent. If the TRTYPE is QERR, any error resulting */\n/* from accessing the database has to be sent in a reply. */\n\nSEND_REPLY: PROC;\n\nIF ((TRANS_TYPE = 'QALL') |\n ((TRANS_TYPE = 'QERR') &\n (RETURN_CODE ¬= RET_GOOD))) THEN /* Return code from */\n /* accessing the database */\n DO;\n\n /**************************************************************/\n /* Interchange origin and destination of netid, domain name */\n /* and task name. The codes are NOT shown here. */\n /**************************************************************/\n\n /**************************************************************/\n /* After getting the VOCAB, CORR, and RESPCODE which are */\n /* relevant to your application, you may want to form the */\n /* parameter list (a singly linked list). If there is no */\n /* parameter list, you should initialize the parameter PARMS */\n /* to Null. This code is NOT shown here. */\n /**************************************************************/\n\n CALL CNMESTR (BHLBPTR, TRANSID, TRTYPE, DESTNET,\n DESTDOM, DESTTASK, ORIGNET, ORIGDOM,\n ORIGTASK, VOCAB, CORR, RESPCODE, PARMS);\n\nFigure 13. Example of a PL/I Program Using the Server Support API (Part 16 of 17)\nExample C Program Using the Server Support API\n\nFigure 14 on page 42 is an example of a C program that uses the server support API. You can use this as a model for creating your own C program.\n/* C DRIVER -- A database server written in C that drives the NetView/Bridge server support API. */\n\n#include files needed\n\nThe following standard #include files are needed to compile this program:\n\nstdio string stdefs\nstdarg stdlib stdlib\n\nThe following NetView/Bridge #include files are also needed. These are included by dsibc.\n\ndsicprm - defines the parameter data structure\ndsibchlb - defines the HLB data structure\ndsibccnm - defines the return codes for the Server Support API routines\ndsibccal - function and macro call definitions for the Server Support API\ndsicvarc - defines the varying-length character string\n\n#pragma runopts (NOEXECOPS,ISASIZE(4K),ISAINC(4K))\n\n#include <stdio.h>\n#include <string.h>\n#include <stdefs.h>\n#include <stdlib.h>\n#include <stdarg.h>\n#include \"dsibc.h\" /* Includes NetView/Bridge files */\n#define NOT_AN_INDEX -32767\n#define MAX_PARMS 200 /* Maximum number of parameters */\n#define EBCDIC 0x00EE\n#define BINARY 0x00BB\n\nFigure 14. Example of a C Program Using the Server Support API (Part 1 of 10)\n/**************************************************************************/\n/* ECB constants */\n**************************************************************************/\n#define ENDLIST 0x80000000 /* Mark end of list */\n#define POSTED 0x40000000 /* Was the ECB posted */\n\nDsibhlb *Bhlbptr; /* Pointer to the Server Support API HLB */\n\n/**************************************************************************/\n/* ECB constants */\n**************************************************************************/\n\nvoid Gethdr(); /* Get header routine */\nvoid getecb(long *ecbaddr, char *jobname); /* Get communications ECB routine */\n\n/**************************************************************************/\n/* Define a 32 byte varying length character string */\n**************************************************************************/\ntypedef struct {\n short size;\n char buffer[32];\n} D32varch;\n\n/**************************************************************************/\n/* MAINLINE */\n/**************************************************************************/\nmain()\n{\n /**************************************************************************/\n /* Parameters */\n /**************************************************************************/\n char tinq[9], tioutq[9]; /* DTS queues names */\n int tinqlim; /* Input queue limit */\n long *waecbp; /* Pointer to ECB's */\n long ecbaddr,ecblist,ecb; /* Event control block, list */\n\n Dsicprm Parm[MAX_PARMS]; /* Array of parameter blocks */\n Dsicprm *Parms; /* Pointer to first parm */\n Dsicprm *Curr; /* Pointer to current parm */\n char Parmlist[MAX_PARMS][256]; /* Array of parameter values */\n\n /**************************************************************************/\n /* ECB constants */\n /**************************************************************************/\n void Gethdr(); /* Get header routine */\n void getecb(long *ecbaddr, char *jobname); /* Get communications ECB routine */\n\n /**************************************************************************/\n /* Define a 32 byte varying length character string */\n /**************************************************************************/\ntypedef struct {\n short size;\n char buffer[32];\n } D32varch;\n\n /**************************************************************************/\n /* MAINLINE */\n /**************************************************************************/\n main()\n {\n /**************************************************************************/\n /* Parameters */\n /**************************************************************************/\n char tinq[9], tioutq[9]; /* DTS queues names */\n int tinqlim; /* Input queue limit */\n long *waecbp; /* Pointer to ECB's */\n long ecbaddr,ecblist,ecb; /* Event control block, list */\n\n Dsicprm Parm[MAX_PARMS]; /* Array of parameter blocks */\n Dsicprm *Parms; /* Pointer to first parm */\n Dsicprm *Curr; /* Pointer to current parm */\n char Parmlist[MAX_PARMS][256]; /* Array of parameter values */\n\n Figure 14. Example of a C Program Using the Server Support API (Part 2 of 10)\nFigure 14. Example of a C Program Using the Server Support API (Part 3 of 10)\n/* Initialize the NetView/Bridge Server Support API */\n\nstrcpy(tiinq,\"CINPUTQ1\"); /* Not previously defined */\nstrcpy(tioutq,\"OUTPUTQ1\"); /* Output queue in RTRINIT */\ntiinqlim = 4; /* 4 x # of ready tokens */\n\nCnmetin(tiinq,tiinqlim,tioutq);\n\n/* Loop forever - Exit when a QUIESCE is received */\n\nfor (;;) {\n /* Note : The ready tokens on the queue upon initialization */\n /* will be handled prior to issuing more ready tokens. */\n /* Get Next Transaction Request */\n /* A get transaction with an empty queue issues RET_NOT_FOUND. */\n /* In this case, emptyq is set to true, we will issue a ready */\n /* token, wait for a transaction, and receive it when it comes. */\n /* If the queue starts off non-empty, we don't want to issue a */\n /* ready token. The transaction will be received and emptyq */\n /* is set to false. All transactions on the queue will be */\n /* processed prior to issuing a ready token. */\n\n if (!cleanq) {\n Cnmentr();\n rc = Bhlbptr->Hlbrc;\n if (rc == RET_GOOD)\n emptyq = 0;\n else\n emptyq = 1;\n }\n}\n\nFigure 14. Example of a C Program Using the Server Support API (Part 4 of 10)\nif (emptyq) { \n\n/* Upon entering this if, we know the queue has been cleaned */\ncleanq = 1;\n\n/* Ready for next transaction request */\n/* Issue a ready if not already in quiesced state */\nif (!quiesced)\n Cnmertr();\n\n/* Wait for transaction request or ECB posting */\n\n/* A stop command issued from the console will post the communications ECB causing the C Driver to terminate. */\n\n/* Set up correct waecbp */\n/* Get ecb address and jobname from assembler program */\ngetecb(&ecbaddr, jobname);\njobname[strlen(jobname)] = '\\0';\necb = *((long *) ecbaddr);\necblist = ecbaddr; /* ecblist has addr of ecb */\necblist = ecblist | ENDLIST; /* Set 0 bit to 1 */\nwaecbp = &ecblist;\nCnmewat(&waecbp);\nrc=Bhlbptr->Hlbrc;\n\nFigure 14. Example of a C Program Using the Server Support API (Part 5 of 10)\nFigure 14. Example of a C Program Using the Server Support API (Part 6 of 10)\n/* Get header parameters */\nGethdr(\"TRANSID \",Transid,8);\nGethdr(\"TRTYPE \",Trtype,4);\nGethdr(\"CORR \",Corr,8);\nGethdr(\"VOCAB \",Vocab,8);\nGethdr(\"DESTNET \",Destnet,8);\nGethdr(\"DESTDOM \",Destdom,8);\nGethdr(\"DESTTASK\",Desttask,8);\nGethdr(\"ORIGNET \",Orignet,8);\nGethdr(\"ORIGDOM \",Origdom,8);\nGethdr(\"ORIGTASK\",Origtask,8);\n\n/* If transid = CNMQUISE then */\n/* 1) If Origtask is this server's TIINQ name */\n/* and in a quiesced state */\n/* then send terminate. */\n/* 2) If Origtask is this server's TIINQ name */\n/* and not in a quiesced state */\n/* then ignore. */\nif (!strcmp(Transid,\"CNMQUISE\")) {\n if ((!strcmp(Origtask,tiinq)) && (quiesced)) {\n Cnmetrm(); /* Terminate Server Support API */\n exit(999);\n } /* Quiesced by autotask */\n} /* Transid of QUIESCE */\nelse {\n gpmethod = 'N';\ngpdatlen = 256;\ngpcursor = 0;\ngpcount = 0;\nCnmegtp(&gpmethod,gpnameh,&gpnamep,&gpindex,\n&gpdata,gpdatlen,&gptype,&gpcursor);\nrc=Bhlbptr->Hlbrc;\nwhile (((rc==RET_GOOD) || (rc==RET_DATA_TRUNC))\n && (gpcount < maxp)) {\n actlen = Bhlbptr->Hlbleng;\n //...\nif (rc == RET_DATA_TRUNC)\n actlen = gpdatlen;\n\n Alternately, and not shown here, the server may recall the gpnamep, gptype, and gpindex. With this information Cnmegtp by name may be called with an adequate buffer.\n\n gpnamep.buffer = \\0;\n gpdata.buffer = \\0;\n\n strcpy(Parm.prmname, gpnamep.buffer);\n Parm.prmnaml = gpnamep.size;\n Parm.prmindex = gpindex;\n strcpy(Parm.prmtype, gptype);\n strcpy(Parm.prmtr, gpdata.buffer);\n Parm.prmtr = Parm.prmtr[gpcount];\n Parm.prmtype = Parm.prmtype[gpcount];\n Parm.prmindex = Parm.prmindex[gpcount];\n Parm.prmname = Parm.prmname[gpcount];\n Parm.prmlen = actlen;\n if (gpcount < maxp)\n Parm.prmtype = &Parm.prmtype[gpcount+1];\n gpcount++;\n Cnmegtp(gpmethod, gpmethod, gpname, &gpindex,\n &gpdata, gpdatlen, &gptype, &gpcursor);\n\n Parm.prmtype = NULL;\n\nFigure 14. Example of a C Program Using the Server Support API (Part 8 of 10)\n/**************************************************************/\n/* Process transactions */\n/* Make calls to routines to interact with database or other */\n/* server. Send in parameter list on input. Set Respcode */\n/* and parameter list on output from these routines. */\n/* Following are sample invocations of server defined */\n/* processing routines. */\n/**************************************************************/\nif (!strcmp(Transid,\"CREATE\"))\n Create(Respcode,Parm);\nelse\n if (!strcmp(Transid,\"SEARCH\"))\n Search(Respcode,Parm);\n else\n if (!strcmp(Transid,\"UPDATE\"))\n Update(Respcode,Parm);\n/**************************************************************/\n/* Send the transaction reply */\n/* (Note that the origin and destination parameters have */\n/* been interchanged) */\n/**************************************************************/\n/**************************************************************/\n/* If Trtype = QERR and Respcode != 0 or if Trtype = QALL, */\n/* we will return the message, else continue to next */\n/**************************************************************/\nif (((!strcmp(Trtype,\"QERR\")) && (!strcmp(Respcode,\n\"00000000\"))) || (!strcmp(Trtype,\"QALL\"))) {\n strcpy(Trtype,\"RPLY\");\n Cmestr(Transid,Trtype,Orignet,Origdom,Origtask,\n Destnet,Destdom,Desttask,Vocab,Corr,Respcode,&Parms);\n} /* End of Send Reply Loop */\n/* End of Transid not Quiesce */\ncleanq = 0;\n} /* End of Processing Loop */\n/* End of Main */\n\nFigure 14. Example of a C Program Using the Server Support API (Part 9 of 10)\nAssembler Source Code for Obtaining the Address of the Communications ECB\n\nFigure 15 on page 52 is an example of an assembler program that you can use to obtain the address of the communications event control block (ECB):\nFUNCTION:\nTHIS MODULE PASSES TO THE CALLER THE JOBNAME OF THIS JOB/TASK\nAND THE ADDRESS OF THE COMMUNICATIONS ECB FOR STOP/MODIFY\nCOMMANDS.\n\nNOTES:\nREGISTER CONVENTIONS: STANDARD MVS/370 LINKAGE CONVENTIONS\n\nMODULE CHARACTERISTICS:\nPROCESSOR: ASSEMBLER H VERSION 2\nTYPE: PROCEDURE\nSIZE: SEE ASSEMBLER LISTING\nATTRIBUTES: RENT,REUS,AMODE ANY,RMODE ANY\n\nPROCEDURE INVOCATION: CALL GETECB(ECB_ADDRESS,JOB_NAME);\n\nINPUT:\nR1-> ADDRESS OF PARAMETER LIST\n+0 ADDRESS OF ADDRESS OF COMMUNICATIONS ECB\n+4 ADDRESS OF JOBNAME\n\nR12-> PL/I TCA (NOT MODIFIED)\nR13-> REGISTER SAVE AREA\nR14= RETURN ADDRESS\nR15= ENTRY ADDRESS\n\nOUTPUT:\nR1-> ADDRESS OF PARAMETER LIST\n+0 ADDRESS OF ADDRESS OF COMMUNICATIONS ECB\n+4 ADDRESS OF JOBNAME\n\nRETURN CODES - NONE.\n\nMACROS:\nEXECUTABLE:\nSAVE\nGETMAIN\nFREEMAIN\nEXTRACT\nRETURN\n\nFigure 15. Assembler Code for Obtaining the Address of the Communications ECB (Part 1 of 4)\n* NON-EXECUTABLE:\n* IEZCOM - MAP COMM AREA\n* IEFTIOT - MAP TASK INPUT OUTPUT TABLE\n*\n***********************************************************************\nGETECB CSECT\nGETECB AMODE ANY\nGETECB RMODE ANY\nSPACE\n USING GETECB,R15\n B AFTRID\n DC 'GETECB &SYSDATE &SYSTIME'\nSPACE\nAFTRID DS 0H\nSAVE (14,12)\nDROP R15\nLR R11,R15 LOAD BASE REGISTER\nUSING GETECB,R11 SET UP CSECT ADDRESSABILITY\nLR R3,R1 SAVE ADDRESS OF PARM LIST\nGETMAIN RU,LV=WORKLEN,LOC=BELOW SAVE AREA AND WORK AREA\nST R13,4(R1) \nST R1,8(R13) \nLR R13,R1 USING WORKAREA,R13\nSPACE\nMVC EXTRA(EXTLEN),EXTRACT MOVE EXTRACT TO BELOW LINE\nEXTRACT TOOTH,'S',FIELDS=(TIOT,COMM),MF=(E,EXTRA)\nSPACE\nL R5,COMMADDR GET ADDRESS OF COMMUNICATIONS AREA\nUSING COMLIST,R5\nL R6,COMECPBT GET ADDRESS OF COMM ECB\nL R4,0(R3) GET FIRST PARAMETER ADDRESS\nST R6,0(R4) STORE COMM ECB ADDRESS IN FIRST PARM\nSPACE\nL R5,TIOTADDR GET ADDRESS OF TIOT\nUSING TIOT,R5\nL R4,4(R3) GET SECOND PARAMETER ADDRESS\nMVC 0(8,R4),TIOCNJOB MOVE JOBNAME TO SECOND PARAMETER\nSPACE\nEXIT EQU *\nLR R10,R13\nL R13,4(R13)\nFREEMAIN RU,LV=WORKLEN,A=(R10)\nRETURN (14,12)\nEJECT\n\nFigure 15. Assembler Code for Obtaining the Address of the Communications ECB (Part 2 of 4)\nFigure 15. Assembler Code for Obtaining the Address of the Communications ECB (Part 3 of 4)\n\nR8 EQU 8\nR9 EQU 9\nR10 EQU 10\nR11 EQU 11\nR12 EQU 12\nR13 EQU 13\nR14 EQU 14\nR15 EQU 15\nEND GETECB\n\nFigure 15. Assembler Code for Obtaining the Address of the Communications ECB (Part 4 of 4)\nChapter 4. Writing a NetView Bridge Command Procedure\nUsing the NetView Bridge Requestor API\n\nThis chapter describes general-use programming interface and associated guidance information.\n\nThis chapter describes how to write command procedures using REXX or NetView command list language, and another set of procedures for writing command procedures using PL/I or C.\n\nIf you are not familiar with writing command procedures for the NetView program, refer to Tivoli NetView for OS/390 Customization: Using REXX and the NetView Command List Language, or Tivoli NetView for OS/390 Customization: Using PL/I and C.\n\nUnderstanding Transaction Size Limitations\n\nA total of 31K bytes is available for a single transaction, which includes all user data combined with packaging code that must accompany your parameters, but excludes header information.\n\n**Note:** The actual limit to the size of a transaction is slightly greater than 31K. However, staying within the 31K limit prevents error conditions or truncated replies.\n\nHeader Information\n\nHeader information is data that is automatically included in every transaction, such as:\n- Correlator information\n- Destination information\n- Origination information\n- Transaction ID\n- Transaction type\n- Vocabulary parameter\n\nHeader information does not count toward the allowed maximum of 31K bytes.\n\nUser Data\n\nUser data consists of the many parameters that are used by your database server. This is the server-specific information that is passed in transactions.\n\nPackaging Code\n\nPackaging code envelopes the parameter information passed by NetView Bridge. There are 23 bytes of packaging code attached to each parameter.\n\nSize of a Parameter\n\nEach parameter consists of a name, type, and value. The method for calculating the size of a packaged parameter is:\n\n\\[\n\\text{size of the packaged parameter} = 23 + \\text{length of parameter name} + \\text{length of parameter value}\n\\]\nTotal Size of a Transaction\n\nTo determine the total size of a transaction, calculate the packaged parameter length of each parameter in a transaction and add the results.\n\nNote: The total size must be less than 31K. If the size of a transaction request exceeds 31K, the NetView Bridge Requester API rejects it. If the size of a transaction reply exceeds 31K, it is truncated to 31K, and forwarded. However, the program that sends the reply receives a nonzero return code.\n\nWriting Command Procedures Using REXX or the NetView Command List Language\n\nThis section describes the procedures for creating a command procedure to work with NetView Bridge using either the REXX or NetView command list language. Examples of command procedures are included as models for creating a command procedure. See Figure 16 on page 58 and Figure 17 on page 62 for more information.\n\nThe following steps, along with Figure 16 and Figure 17, assume that the command procedure is being run under an operator station task (OST). If you want to write command procedures to run under the primary program operator interface task (PPT), you must use the NetView automation table to capture the NetView Bridge message DWO548I and drive another command procedure to process the reply. Refer to Tivoli NetView for OS/390 Automation Guide for a description of this procedure.\n\nNote: Running under the PPT is not recommended because you cannot wait for transaction replies. The PPT does not support waits.\n\nComplete the following steps in order.\n\nStep 1. Initializing Parameters\n\nAt the beginning of your command procedure, assign values to initialize all parameters for the transactions you want to execute. See TRANSND—Send Transaction Request to Database Server on page 91 for complete details on the parameters, their usage, and syntax.\n\nSee your server documentation for details on any parameters your server may require to process your transaction.\n\nStep 2. Preparing to Receive the Reply\n\nWrite the lines of code to prepare for receiving the reply.\n\nIf you are writing this transaction using REXX, issue the NetView TRAP command (see Figure 16 on page 58). This traps message DWO548I. (Message DWO548I is the first line of the two-line message used to send a transaction reply back to the NetView Requester API requesting command procedure.)\n\nIf you are writing this transaction using the NetView command list language, issue the &WAIT command (see Figure 17 on page 62). This causes your command procedure to wait on the receipt of message DWO548I.\nStep 3. Sending the Transaction Request\n\nWrite the lines of code to issue the NetView Bridge TRANSND command. See [TRANSND—Send Transaction Request to Database Server on page 91] for more information on the TRANSND command.\n\nYou can send transactions across networks or domains by changing DESTNET and DESTDOM to the remote network name or remote domain name of your choice, respectively.\n\n**Note:** For a NetView command list language command procedure, this command is already part of the &WAIT statement.\n\nStep 4. Processing the Reply\n\nWrite the lines of code to process the reply.\n\nIf you are writing this transaction using REXX, issue the NetView MSGREAD command to read the trapped message DWO548I from the message queue, followed by the TRANRCV command to process the reply parameters (see Figure 16 on page 58).\n\nIf you are writing this transaction using the NetView command list language, issue the TRANRCV command (see Figure 17 on page 62).\n\nWith the REXX or NetView command list language, the TRANRCV command creates local variables into which the reply data is placed. See [TRANRCV—Receive a Transaction Reply on page 94] for a list of these variables.\n\nAt this point, you can also write the necessary code to process the reply data in any manner you want.\n\nExample of a Command Processor Using REXX\n\nFigure 16 on page 58 is an example of a REXX EXEC that uses the TRANSND and TRANRCV commands. You might want to use this example as a model for creating your own command processor.\nThe following is a sample of a REXX program, designed to utilize the functions of the NetView Bridge.\n\nSet parameter values\n\nPARM1='VALUE1'\nPARM2='VALUE2'\n\nMULTI_VALUE_PARM.0=2 /* Number of elements in array */\nMULTI_VALUE_PARM.1='THIS IS A SAMPLE OF USING AN ARRAY'\nMULTI_VALUE_PARM.2='TO SPECIFY A MULTI-VALUE PARAMETER.'\n\nSet TRANSND values\n\nTRANSID='CREATE' /* Transaction name */\nTRTYPE='QALL' /* Transaction type */\nDESTNET='NETA' /* Destination network name */\nDESTDOM='CNM01' /* Destination domain name */\nDESTTASK='BRDGDSPI' /* BRIDGE dispatcher name */\nVOCAB='TABLE1' /* VOCAB table name */\nCORR='CORRVAL' /* Correlator value */\n\nPARMVAR='PARM1 PARM2 MULTI_VALUE_PARM. '\n\nPrepare for reply, then request transaction execution\n\nTRAP AND SUPPRESS ONLY MESSAGES DWO548I\n'TRANSND TRANSID='TRANSID',TRTYPE='TRTYPE',DESTNET='DESTNET,' 'DESTDOM='DESTDOM',DESTTASK='DESTTASK',VOCAB='VOCAB,' 'CORR='CORR',PARMVAR=PARMVAR'\n\nIf rc ¬= 0 Then /* TRANSND command failed */\n Call EXIT_ROUTINE TRANSNDERR rc\nElse /* TRANSND command rc = 0 */\n Do\n /**********************************************************/\n /* Process all DWO548I messages. Loop until we receive a */\n /* matching RPCORREL value, or until we EXIT due to an error. */\n /**********************************************************/\n say 'TRANSND command rc = 0 -- Waiting for reply...'\n FLAG = 0\n Do until FLAG = 1\n Call DWOPROC\n Call PRINTOUT\n\nFigure 16. Example of a REXX EXEC Using TRANSND and TRANRCV (Part 1 of 4)\nIf RPCORREL ≠ CORREL Then /* Wrong DWO548I message received */\n say 'Correlators do not match...'\nElse\n FLAG = 1\nEnd\nEnd /* End else */\nCall EXIT_ROUTINE NOERR\n\nDWOPROC:\n'WAIT 2 MINUTES FOR MESSAGES ' \nSelect\n When EVENT() = 'M' Then\n Do\n say 'TRANSND reply(DWO548I) received...' \n 'MSGREAD'\n 'TRANRCV PARMVAR=TRRCVVAR' /* Request reply parameters */\n Select\n When rc = 2 Then\n say 'Parm name or value truncated -- Processing continues...'\n When rc = 0 Then\n say 'TRANRCV command rc = 0 -- Processing continues...'\n Otherwise\n Call EXIT_ROUTINE TRRCVERR rc\n End /* End select */\n End\n When EVENT() = 'T' Then\n Call EXIT_ROUTINE TMOUTERR\n When EVENT() = 'G' Then\n Call EXIT_ROUTINE OPGOERR\n Otherwise\n Call EXIT_ROUTINE EVENTERR\n End /* End select */\nReturn /* End DWOPROC */\n\nFigure 16. Example of a REXX EXEC Using TRANSND and TRANRCV (Part 2 of 4)\nPRINTOUT:\n\nsay 'RPTRANSID = 'RPTRANSID\nsay 'RPTRTYPE = 'RPTRTYPE\nsay 'RPDESNET = 'RPDESNET\nsay 'RPDESDOM = 'RPDESDOM\nsay 'RPDESTSK = 'RPDESTSK\nsay 'RPRIGNET = 'RPRIGNET\nsay 'RPRIGDOM = 'RPRIGDOM\nsay 'RPRIGTSK = 'RPRIGTSK\nsay 'RPORREL = 'RPORREL\nsay 'RPVOCAB = 'RPVOCAB\nsay 'RPRESPCODE = 'RPRESPCODE\n\nDo i = 1 to words(TRRCVVAR) /* Loop through list of keywords */\n\nsay word(TRRCVVAR,i) ' = 'value(word(TRRCVVAR,i))\n\nEnd\n\nReturn /* End PRINTOUT */\n\nFigure 16. Example of a REXX EXEC Using TRANSND and TRANRCV (Part 3 of 4)\nExample of a Command Processor Using the NetView Command List Language\n\nFigure 17 on page 62 is an example of a NetView command list that uses the TRANSND and TRANRCV commands. You might want to use this example as a model for creating your own command processor.\nEXAMPLE CLIST\n&CONTROL ERR\n**********************************************************************\n* Sample NetView Command List Language transaction program *\n**********************************************************************\n\n**********************************************************************\n* Set parameter values *\n**********************************************************************\n&PARM1 = 'VALUE1'\n&PARM2 = 'VALUE2'\n\n**********************************************************************\n* Set TRANSND values *\n**********************************************************************\n&TRANSID = 'CREATE'\n&TRTYPE = 'QALL'\n&DESTNET = 'NETA'\n&DESTDOM = 'CNM01'\n&DESTTASK = 'BROGDS1P'\n&VOCAB = 'TABLE1'\n&CORR = 'CORRVAL'\n\n&PARMVAR = 'PARM1 PARM2'\n\n**********************************************************************\n* Prepare for reply, then request transaction execution *\n**********************************************************************\n&WAIT CONTWAIT SUPPRESS\n&WRITE Sending transaction now...\n&WAIT 'TRANSND TRANSID=&TRANSID,TRTYPE=&TRTYPE,DESTNET= &DESTNET,+\n &DESTDOM=&DESTDOM,DESTTASK=&DESTTASK,VOCAB=&VOCAB,+\n CORR=&CORR,PARMVAR=PARMVAR' DWO548I=-DWOPROC +\n *120=-TMOUTERR *ERROR=-TRSNDERR *ENDWAIT=-OPGOERR\n\n**********************************************************************\n* DWOPROC *\n**********************************************************************\n-DWOPROC\n&WRITE TRANSND reply (DWO548I) received...\nTRANRCV PARMVAR=TRRCVVAR\n&IF &RETCODE = 0 &THEN &GOTO -OKRC\n&IF &RETCODE ¬= 2 &THEN &GOTO -TRRCVERR\n&WRITE Parm name or value truncated\n-OKRC\n&WRITE TRANRCV command rc = &RETCODE Processing continues...\n\nFigure 17. Example of a NetView Command List using TRANSND and TRANRCV (Part 1 of 3)\nFigure 17. Example of a NetView Command List using TRANSND and TRANRCV (Part 2 of 3)\nWriting Command Procedures Using PL/I or C\n\nThis section describes the procedures for creating a command procedure to work with NetView Bridge using either the PL/I or C programming language. Because VM and VSE do not support HLLs, such as PL/I and C, this section only applies to NetView Bridge running on MVS. Examples of command procedures are included as models for creating a command procedure (see Figure 18 on page 66 and Figure 19 on page 71).\n\nThe following steps, along with Figure 18 and Figure 19, assume that the command procedure is being run under an operator station task (OST). If you want to write command procedures to run under the primary program operator interface task (PPT), you must use the NetView automation table to capture the NetView Bridge message DWO548I and drive another command procedure to process the reply. See [The Automation Table] in [Tivoli NetView for OS/390 Automation Guide] for a description of this procedure.\n\n**Note:** Running under the PPT is not recommended because you cannot wait for transaction replies. The PPT does not support waits.\n\nComplete the following steps in order.\n\n---\n\n-CHEKCORR\n**********************************************************************\n* Determine whether this is the reply I am waiting for *\n**********************************************************************\n&IF &RPCORREL = &CORR &THEN &GOTO -DONE\n&WRITE Correlators do not match...\n&WAIT CONTINUE\n\n-DONE\n&WAIT ENDWAIT\nGO\n&WRITE Program completed successfully...\n&GOTO -END\n\n-OPGOERR\n&WRITE Operator entered \"GO\" command... Terminated \"WAIT\" state...\n&GOTO -END\n\n-TRSNDERR\n&WRITE TRANSND failed with rc = &RETCODE\n&GOTO -END\n\n-TMOUTERR\n&WRITE No DWO548I message received... Timed out after 2 minutes...\n&GOTO -END\n\n-TRRCVERR\n&WRITE TRANRCV failed with rc = &RETCODE\n&GOTO -END\n\n-END\n&WRITE EXAMPLE complete\n&EXIT\n\n---\n\nFigure 17. Example of a NetView Command List using TRANSND and TRANRCV (Part 3 of 3)\nStep 1. Initializing Parameters and Using Transaction Parameter Blocks\n\nThe NetView program contains a parameter block structure specifically for use with the NetView Bridge Requester API service routine CNMSNDT (send a transaction request). The parameter block structure has two separate versions—one for PL/I (DSIPPRM) and one for C (DSICPRM).\n\nWhen you write the code to initialize your parameters, place each nonheader parameter in its own allocated copy of the parameter block structure. Your code must then store the required information for this parameter in this parameter block structure.\n\nFinally, write code to link these parameter block structures together for use by the CNMSNDT service routine. To do this, set the pointer field (PRMLINK) in each parameter block to link them all together. (See Figure 8 on page 21 for an example of how this is done.)\n\nAt the beginning of your command procedure, assign values to initialize the appropriate parameters for the transactions you want to execute. Refer to “CNMSNDT (CNMSENDTR)—Send Transaction Request to Database Server” on page 96 for complete details on the parameters, their usage, and syntax.\n\nSee your server documentation for details on any parameters your server may require to process your transaction.\n\nStep 2. Preparing to Receive the Reply\n\nWrite the lines of code to prepare for receiving the reply.\n\nTo do this, invoke the NetView HLL service routine CNMCMMD to issue the TRAP command. This traps message DWO548I. (Message DWO548I is the first line of the two-line message used to send a transaction reply back to the NetView Bridge Requester API requesting command procedure.) See Figure 18 on page 66 or Figure 19 on page 71 for an example of how you might write this code.\n\nStep 3. Sending the Transaction Request\n\nWrite the lines of code to invoke the NetView Bridge service routine CNMSNDT (see Figure 18 and Figure 19). This service routine sends the transaction to the NetView Bridge Requester API.\n\nStep 4. Processing the Reply\n\nTo obtain the reply data using HLL code, you must do two things:\n\n1. Write the code to retrieve the header parameter (method H) using the NetView Bridge HLL service routine CNMGETP.\n2. Write the code to retrieve the parameter information (method N or P) using the NetView Bridge HLL service routine CNMGETP.\n\nSee “CNMGETP (CNMGETPARM)—Get Transaction Reply Parameters” on page 106 for details on how to use this service routine.\n\nAt this point, you can also write the code necessary to process the reply data in any manner you want.\nStep 5. Compiling and Link-Editing Your HLL Command Procedures\n\nAt this point, you need to compile and link-edit your HLL command procedures. See \"Compiling, Link-Editing, and Running Your HLL Program\" in \"Tivoli NetView for OS/390 Customization: Using PL/I and C\" for detailed instructions on this process.\n\nExample of a Command Processor Using PL/I\n\nFigure 18 is an example of a PL/I program that uses the NetView Bridge Requester API. You might want to use this example as a model for creating your own command processor.\n\nNote: VM and VSE do not support PL/I or other HLLs.\n\n```pli\nPLISAMP: PROC(HLBPTR,CMDBUF,ORIGBLCK) OPTIONS(MAIN,REENTRANT);\n/**************************************************************************/\n/**\n/* Sample PL/I language transaction command processor */\n/**\n/* This sample command processor builds a transaction and */\n/* sends it across the NetView bridge product. It is not */\n/* written with any particular server or database in mind as */\n/* all parameters are hard coded. */\n/**\n/* The following are demonstrated by this procedure: */\n/* 1. The correct use of CNMSNDT to send a transaction request */\n/* over the bridge */\n/* 2. The procedure for WAITing and TRAPping on the reply */\n/* 3. The processing of the REPLY parameter using CMGGETP: */\n/* 1. CORR Using CMGGETP method H */\n/* 2. REASONCODE Using CMGGETP method P */\n/* 3. ALL OTHERS Using CMGGETP method N */\n/**\n**************************************************************************/\n%INCLUDE DSIPLI; /* DSIPLI includes required */\n/* control blocks and include */\n/* files */\nDCL HLBPTR PTR; /* Pointer to the HLB */\nDCL CMDBUF CHAR(*) VARYING; /* Command buffer */\nDCL ORIGBLCK CHAR(40); /* Area for the ORIG block */\nDCL ORIGIN PTR; /* Pointer to the ORIG block */\nDCL (ADDR,NULL) BUILTIN;\nDCL LENGTH BUILTIN;\n/**************************************************************************/\n/* Declarations for CNMSNDT */\n/**************************************************************************/\nDCL TRANSID CHAR(8) INIT('CREATE '); /* Transaction ID */\nDCL TRTYPE CHAR(4) INIT('QALL'); /* Transaction type */\nDCL DESTNET CHAR(8) INIT('NETA '); /* Destination network name */\nDCL DESTDOM CHAR(8) INIT('CNM01 '); /* Destination domain name */\nDCL DESTTASK CHAR(8) INIT('BRDGDSPI1'); /* Bridge dispatcher name */\nDCL VOCAB CHAR(8) INIT('TABLE1 '); /* Vocab table name */\nDCL CORR CHAR(8) INIT('CORRVAL '); /* Correlator value */\nDCL PARMLIST PTR; /* Pointer to parameter block */\nDCL STARTPTR PTR; /* Pointer to the beginning of */\n/* the parameter list */\nDCL NOT_AN_INDEX CHAR(6) INIT('-32767');\n```\n\nFigure 18. Example of a PL/I Program Using the NetView Bridge Requester API (Part 1 of 5)\n/* Declarations for CNMGETP */\nDCL GPMETHOD CHAR(1); /* GET method (H,P,N) */\nDCL GPNAMEH CHAR(8); /* Header name area */\nDCL GPNAMEP CHAR(31) VARYING; /* Parameter name area */\nDCL GPINDEX FIXED BIN(31,0) INIT(0); /* Index value */\nDCL GPDATA CHAR(256) VARYING; /* Data buffer area */\nDCL GPDATLEN FIXED BIN(31,0) INIT(256); /* Max length of data */\nDCL GPTYPE BIT(16) INIT('00EE' BX); /* EBCDIC or BINARY */\nDCL GPQUEUE FIXED BIN(31,0) INIT(TRAPQ); /* Data queue */\nDCL GPCURSOR FIXED BIN(31,0) INIT(0); /* Cursor location in msg */\nDCL P1NAM CHAR(9) INIT('PARMNAME1');\nDCL P1VAL CHAR(6) INIT('VALUE1');\nDCL P2NAM CHAR(9) INIT('PARMNAME2');\nDCL P2VAL CHAR(6) INIT('VALUE2');\nDCL P3NAM CHAR(8) INIT('MULTIPARM'); /* P3NAM and P4NAM are */\nDCL P3VAL CHAR(31) INIT('MULTIVALUE1'); /* used to show how to */\nDCL P4NAM CHAR(8) INIT('MULTIPARM'); /* use multi-line */\nDCL P4VAL CHAR(31) INIT('MULTIVALUE2'); /* parameters */\n\n/* Construct the linked list of parameters. Allocate and */\n/* initialize the first parameter block. */\nALLOCATE DSIPPRM SET (PARMLIST);\nSTARTPTR = PARMLIST; /* Start of linked list */\nPARMLIST -> PRMINDEX = NOT_AN_INDEX; /* Index set to -32767 */\nPARMLIST -> PRMNAML = LENGTH(P1NAM); /* Length of 1st parm name */\nPARMLIST -> PRMNAME = P1NAM; /* 1st parm name */\nPARMLIST -> PRMTYPE = PRM_TYPEEBDC; /* 1st parm is in EBCDIC */\nPARMLIST -> PRMLENG = LENGTH(P1VAL); /* Length of 1st parm value */\nPARMLIST -> PRMPTR = ADDR(P1VAL); /* Address of 1st parm value */\n\n/* Allocate and initialize second parameter block */\nALLOCATE DSIPPRM SET(PARMLIST -> PRMLINK);\nPARMLIST = PARMLIST -> PRMLINK; /* Link to 2nd parm in list */\nPARMLIST -> PRMINDEX = NOT_AN_INDEX; /* Index set to -32767 */\nPARMLIST -> PRMNAML = LENGTH(P2NAM); /* Length of 2nd parm name */\nPARMLIST -> PRMNAME = P2NAM; /* 2nd parm name */\nPARMLIST -> PRMTYPE = PRM_TYPEEBDC; /* 2nd parm is in EBCDIC */\nPARMLIST -> PRMLENG = LENGTH(P2VAL); /* Length of 2nd parm value */\nPARMLIST -> PRMPTR = ADDR(P2VAL); /* Address of 2nd parm value */\n\nFigure 18. Example of a PL/I Program Using the NetView Bridge Requestor API (Part 2 of 5)\n/* Allocate and initialize third parameter block */\nALLOCATE DSIPPRM SET(PARMLIST -> PRMLINK);\nPARMLIST = PARMLIST -> PRMLINK; /* Link to 3rd parm in list */\nPARMLIST -> PRMINDEX = 1; /* 1st line of multi-parm */\nPARMLIST -> PRMNAML = LENGTH(P3NAM); /* Length of 3rd parm name */\nPARMLIST -> PRMNAME = P3NAM; /* 3rd parm name */\nPARMLIST -> PRMTYPE = PRM_TYPEEBDC; /* 3rd parm is in EBCDIC */\nPARMLIST -> PRMLENG = LENGTH(P3VAL); /* Length of 3rd parm value */\nPARMLIST -> PRMPTR = ADDR(P3VAL); /* Address of 3rd parm value */\n\n/* Allocate and initialize fourth parameter block */\nALLOCATE DSIPPRM SET(PARMLIST -> PRMLINK);\nPARMLIST = PARMLIST -> PRMLINK; /* Link to 4th parm in list */\nPARMLIST -> PRMINDEX = 2; /* 2nd line of multi-parm */\nPARMLIST -> PRMNAML = LENGTH(P4NAM); /* Length of 4th parm name */\nPARMLIST -> PRMNAME = P4NAM; /* 4th parm name */\nPARMLIST -> PRMTYPE = PRM_TYPEEBDC; /* 4th parm is in EBCDIC */\nPARMLIST -> PRMLENG = LENGTH(P4VAL); /* Length of 4th parm value */\nPARMLIST -> PRMPTR = ADDR(P4VAL); /* Address of 4th parm value */\nPARMLIST -> PRMLINK = NULL; /* Terminate linked list */\n\n/* Prepare for REPLY */\nCALL CNMCMD(HLBPTR,'TRAP AND SUPPRESS ONLY MESSAGES DWO548I');\n\n/* Send transaction */\nCALL CNMSNDT(HLBPTR,TRANSID,TRTYPE,DESTNET,DESTDOM,\n DESTTASK,VOCAB,CORR,STARTPTR);\nIF HLBRC ≠ CNM_GOOD THEN\n DO; /* Unsuccessful CNMSNDT */\n CALL CNMSMSG(HLBPTR,'CNMSNDT RETURN CODE BAD, HLBRC ='||HLBRC,\n 'MSG','OPER',');\n CALL EXIT(99);\n END;\n\nFigure 18. Example of a PL/I Program Using the NetView Bridge Requester API (Part 3 of 5)\n/**\n * WAIT for DWO548I message\n */\nCALL CNMCMD(HLBPTR,'WAIT 60 SECONDS FOR MESSAGES');\nIF HLBRC ¬= CNM_MSG_ON_WAIT THEN\n DO;\n CALL CNMSMSG(HLBPTR,'MESSAGE WAIT NOT SATISFIED, HLBRC ='||HLBRC,\n 'MSG','OPER',');\n CALL EXIT(99);\n END;\n/**\n * Process REPLY and retrieve header parameter\n */\nCALL CNMGETP(HLBPTR,BYHEADER,'CORR ',GPNAMEP,GPINDEX,\n GPDATA,GPDATLEN,GPTYPE,GPQUEUE,GPCURSOR);\nIF HLBRC = CNM_GOOD THEN\n DO;\n IF CORR ¬= 'CORRVAL' THEN\n CALL CNMSMSG(HLBPTR,'CORRELATOR NOT MATCHED','MSG','OPER',');\n CALL CNMSMSG(HLBPTR,'CORR = '||GPDATA,'MSG','OPER',');\n END;\n ELSE\n CALL CNMSMSG(HLBPTR,'CNMGETP FOR CORR FAILED,HLBRC='||HLBRC,\n 'MSG','OPER',');\n END;\n/**\n * Retrieve parameter by name\n */\nCALL CNMGETP(HLBPTR,BYNAME,' ','REASONCODE',GPINDEX,\n GPDATA,GPDATLEN,GPTYPE,GPQUEUE,GPCURSOR);\nIF HLBRC ¬= CNM_GOOD THEN\n CALL CNMSMSG(HLBPTR,'CNMGETP FOR REASONCODE FAILED,HLBRC='||HLBRC,\n 'MSG','OPER',');\n CALL CNMSMSG(HLBPTR,'REASONCODE = '||GPDATA,'MSG','OPER',');\n/**\n * Retrieve parameter by name\n */\nGPINDEX = NOT_AN_INDEX;\nCALL CNMGETP(HLBPTR,BYNAME,' ','REASONCODE',GPINDEX,\n GPDATA,GPDATLEN,GPTYPE,GPQUEUE,GPCURSOR);\nIF HLBRC ¬= CNM_GOOD THEN\n CALL CNMSMSG(HLBPTR,'CNMGETP FOR REASONCODE FAILED,HLBRC='||HLBRC,\n 'MSG','OPER',');\n CALL CNMSMSG(HLBPTR,'REASONCODE = '||GPDATA,'MSG','OPER',');\n\nFigure 18. Example of a PL/I Program Using the NetView Bridge Requester API (Part 4 of 5)\nExample of a Command Processor Using C\n\nFigure 19 on page 71 is an example of a C program that uses the NetView Bridge Requester API. You might want to use this example as a model for creating your own command processor.\n\nNote: VM and VSE do not support C or other HLLs.\n/* Sample C language transaction command processor. */\n/*\n/* This is a sample command processor that sends a transaction */\n/* across the NetView bridge product. The TRANSID and all */\n/* parameters are hard coded and are not related to any specific */\n/* server or database. In a real environment, these values should */\n/* be pulled from some external source.\n/* If the parameters were valid for some database, then the */\n/* expected output would be similar to the following:\n*/\n/*\n/* CORR is CORRVAL <-- Cnmgetp method H */\n/* REASONCODE is 0 <-- Cnmgetp method P */\n/* MESSAGES is RECORD CREATED. <-- Cnmgetp method N */\n/* REASONCODE is 0 <-- Cnmgetp method N */\n/* Sample C transaction program complete. */\n/*\n/***********************************************/\n#pragma runopts(NOEXECOPS,NOSTAE,NOSPIE,ISASIZE(4K),ISAINC(4K))\n#define NOT_AN_INDEX -32767\n\n/**********************************************/\n/* Standard C include files */\n/**********************************************/\n#include <string.h> /* String Functions */\n#include <stdio.h> /* I/O Functions */\n#include <stdefs.h> /* Standard Definitions */\n#include <stdlib.h> /* Standard Library */\n#include <stdarg.h> /* Standard Args */\n#include \"dsic.h\" /* NetView HLL include file */\n\n/**********************************************/\n/* 32 byte varying length character string */\n/**********************************************/\ntypedef struct {\n short size;\n char buffer[32];\n} D32varc;\n\nFigure 19. Example of a C Program Using the NetView Bridge Requester API (Part 1 of 7)\n/* External data definitions */\nDshlb *Hlbptr; /* Pointer to the HLB */\nDsivarch *Cmdbuf; /* Pointer to Command Buffer */\nDsiorig *Origblk; /* Pointer to the Origin Block*/\n\nmain(int argc, char *argv)\n{\n /* Internal data definitions */\n \n /* Parameter list definitions */\n Dsicprm *parms; /* Pointer to parm list */\n Dsicprm parm1, parm2, parm3, parm4; /* Parameter list */\n Dsivarch p1nam, p2nam, p3nam, p4nam; /* Parameter names */\n Dsivarch p1val, p2val, p3val, p4val; /* Parameter values */\n\n /* Cnmgetp definitions */\n char gpmethod; /* GET method (H, P, N) */\n char gpmnameh; /* Header name area */\n D32varc gpmnamep; /* Parameter name area */\n int gpindex; /* Index Value */\n Dsivarch gpdata; /* Data buffer area */\n int gpdatlen; /* Maximum Data length area */\n short gptype; /* EBCDIC or Binary */\n int gpqueue;\n int gpcursor; /* Cursor location in message */\n\n /* Cnmsndt definitions */\n char transid = \"CREATE \"; /* Transaction name */\n char trtype = \"QALL \"; /* Transaction type */\n char destnet = \"NETA \"; /* Network destination */\n char destdom = \"CNM01 \"; /* Domain destination */\n char desttask = \"BRDGDSP1 \"; /* Bridge dispatcher name */\n char vocab = \"TABLE1 \"; /* VOCAB table name */\n char corr = \"CORRVAL \"; /* Transaction correlator */\n\nFigure 19. Example of a C Program Using the NetView Bridge Requester API (Part 2 of 7)\nint rchlb;\nDsivarch message,command;\n\nsscanf(argv[1],\"%x\",&Hlbptr);\nsscanf(argv[2],\"%x\",&cmdbuf);\nsscanf(argv[3],\"%x\",&origblk);\n\nCnmvlc(&1nam,0,\"PARMNAME1\"); /* 1st parameter name */\nCnmvlc(&p1val,0,\"VALUE1\"); /* 1st parameter value */\nCnmvlc(&p2nam,0,\"PARMNAME2\"); /* 2nd parameter name */\nCnmvlc(&p2val,0,\"VALUE2\"); /* 2nd parameter value */\nCnmvlc(&p3nam,0,\"MULTIPARM\"); /* Multi-parameter name */\nCnmvlc(&p3val,0,\"MULTIVALUE1\"); /* 1st multi-parm value */\nCnmvlc(&p4nam,0,\"MULTIPARM\"); /* Multi-parameter name */\nCnmvlc(&p4val,0,\"MULTIVALUE2\"); /* 2nd multi-parm value */\n\nFigure 19. Example of a C Program Using the NetView Bridge Requester API (Part 3 of 7)\nFigure 19. Example of a C Program Using the NetView Bridge Requester API (Part 4 of 7)\nCnmsndt(transid, trtype, destnet, destdom, desttask, vocab, corr, &parms);\nrchlb = Hlbptr->Hlbrc;\nif (rchlb != CNM_GOOD)\n Exit_Rtn(2, rchlb);\n\nCnmvlc(&command, 0, \"WAIT 60 SECONDS FOR MESSAGES\");\nCnmcmd(&command);\nrchlb = Hlbptr->Hlbrc;\nif (rchlb != CNM_MSG_ON_WAIT)\n Exit_Rtn(3, rchlb);\n\ngpindex = 0; /* Initialize gpindex to 0 */\ngpcursor = 0; /* Initialize gpcursor to 0 */\ngpdatalen = 8; /* Set maximum data length */\ngptype = prm_ebdc; /* Initialize gptype to EBCDIC */\ngpqueue = TRAPQ; /* Set gpqueue to 1 (TRAPQ) */\ngpmethod = BYHEADER; /* Set gpmethod to H(BYHEADER) */\nstrcpy(gpnameh, \"CORR \"); /* Copy CORR into gpnameh */\nCnmvlc(&gpnamep, 0, \" \"); /* Blank out gpnamep value */\nCnmgetp(&gpmethod, gpnameh, &gpnamep, &gpindex, &gpdatalen, &gptype, &gpqueue, &gpcursor);\nrchlb = Hlbptr->Hlbrc;\ngpdatalen.buffer??(gpdatalen.size??) = '\\0';\nif (rchlb != CNM_GOOD)\n {\n Cnmvlc(&message, 0, \"Cnmgetp; method H failed. RC = %d\", rchlb);\n Cnmsmsg(&message, MSG, OPER, NULLCHAR);\n }\nelse\n {\n Cnmvlc(&message, 0, \"%s is %s\", gpnameh, gpdatalen.buffer);\n Cnmsmsg(&message, MSG, OPER, NULLCHAR);\n }\n\nFigure 19. Example of a C Program Using the NetView Bridge Requester API (Part 5 of 7)\n/* Get REASONCODE using Cnmgetp with gpmethod of 'P'arameters */\n/* */\ngpindex = NOT_AN_INDEX; /* Initialize gpindex (-32767)*/\ngpcursor = 0; /* Initialize gpcursor to 0 */\ngpdatlen = 8; /* Set maximum data length */\ngptype = prm_ebdc; /* Initialize gptype to EBCDIC*/\ngpqueue = TRAPQ; /* Set gpqueue to 1 (TRAPQ) */\ngpmethod = BYNAME; /* Set gpmethod to P (BYNAME) */\nstrcpy(gpnameh,\" \"); /* Blank out gpnameh */\nCnmvlc(&gpnamep,0,\"REASONCODE\"); /* Set gpnamep to parm name */\nCnmgetp(&gpmethod,gpnameh,&gpnamep,&gpindex,&gpdata,\n gpdatlen,&gptype,gpqueue,&gpcursor);\nrchlb = Hlbptr->Hlbrc;\ngpnamep.buffer??(gpnamep.size??) = '\\0';\ngpdata.buffer??(gpdata.size??) = '\\0';\nif (rchlb != CNM_GOOD)\n{\n Cnmvlc(&message,0,\"Cnmgetp method P failed. RC = %d\",rchlb);\n Cnmsmsg(&message,MSG,OPER,NULLCHAR);\n}\nelse\n{\n Cnmvlc(&message,0,\"%s is %s\",gpnamep.buffer,gpdata.buffer);\n Cnmsmsg(&message,MSG,OPER,NULLCHAR);\n}\n/* */\n/* Get remaining parameters using Cnmgetp with gpmethod of 'N'ext */\n/* */\ngpindex = NOT_AN_INDEX; /* Initialize gpindex (-32767)*/\ngpcursor = 0; /* Initialize gpcursor to 0 */\ngpdatlen = 256; /* Set maximum data length */\ngptype = prm_ebdc; /* Initialize gptype to EBCDIC*/\ngpqueue = TRAPQ; /* Set gpqueue to 1 (TRAPQ) */\ngpmethod = BYNEXT; /* Set gpmethod to N (BYNEXT) */\nstrcpy(gpnameh,\" \"); /* Blank out gpnameh */\nCnmvlc(&gpnamep,0,\" \"); /* Blank out gpnamep */\nCnmgetp(&gpmethod,gpnameh,&gpnamep,&gpindex,&gpdata,\n gpdatlen,&gptype,gpqueue,&gpcursor);\nrchlb = Hlbptr->Hlbrc;\ngpnamep.buffer??(gpnamep.size??) = '\\0';\ngpdata.buffer??(gpdata.size??) = '\\0';\n\nFigure 19. Example of a C Program Using the NetView Bridge Requester API (Part 6 of 7)\nwhile (rchlb == CNM_GOOD)\n{\n Cnmvlc(&message,0,\"%s is %s\",gpnamep.buffer,gpdata.buffer);\n Cnmsmsg(&message,MSG,OPER,NULLCHAR);\n Cnmgetp(&gpmethod,gpnameh,&gpnamep,&gpindex,&gpdata,\n &gpdatlen, &gptype,gpqueue,&gpcursor);\n rchlb = Hlbptr->Hlbrc;\n}\n\nif (rchlb != CNM_NO_MORE_DATA)\n{\n Cnmvlc(&message,0,\"Cnmgetp formethod N failed. RC = %d\",rchlb);\n Cnmsmsg(&message,MSG,OPER,NULLCHAR);\n}\n\nExit_Rtn(0,0);\n\n/***************************************************************\n/* Exit routine */\n/***************************************************************\nExit_Rtn(int exitcode,int rc)\n{\n extern Dsihlb *Hlbptr;\n Dsivarchar message;\n\n switch(exitcode)\n {\n case 1 : Cnmvlc(&message,0,\"Trap command failed. RC = %d\",rc);\n Cnmsmsg(&message,MSG,OPER,NULLCHAR);\n break;\n case 2 : Cnmvlc(&message,0,\"Cnmsndt failed. RC = %d\",rc);\n Cnmsmsg(&message,MSG,OPER,NULLCHAR);\n break;\n case 3 : Cnmvlc(&message,0,\"Wait ended abnormally. RC = %d\",\n rc);\n Cnmsmsg(&message,MSG,OPER,NULLCHAR);\n break;\n default: Cnmvlc(&message,0,\"Processing complete.\");\n Cnmsmsg(&message,MSG,OPER,NULLCHAR);\n break;\n }\n\n Cnmvlc(&message,0,\"Sample C transaction program complete.\");\n Cnmsmsg(&message,MSG,OPER,NULLCHAR);\n exit(0);\n}\n\nFigure 19. Example of a C Program Using the NetView Bridge Requester API (Part 7 of 7)\nChapter 5. Starting NetView Bridge, a Database Server, and NetView Bridge Remote Access\n\nThis chapter describes the step-by-step process for bringing up NetView Bridge, a database server, and the NetView Bridge remote dispatcher and discusses some methods for automating this process.\n\nThe NetView subsystem address space contains the program-to-program interface queues used by NetView Bridge. You must recycle the NetView Bridge dispatcher autotask and the database server every time you assign a different NetView subsystem address space to your NetView environment.\n\nNote: Do not bypass any of the steps in this section. Ensure that you complete each task within each step (in order) before proceeding to the next step.\n\nStep 1. Starting NetView Bridge\n\nTo start NetView Bridge, you must first start the NetView Bridge dispatcher by issuing the following command:\n\nAUTOTASK OPID=BRIGOPER\n\nWhere BRIGOPER is the operator ID that you assigned in \"Step 1. Adding an Operator ID for the Dispatcher Autotask\" on page 8.\n\nThis command starts BRIGOPER as a NetView autotask and automatically executes the RTRINIT command as specified in the profile you created in \"Step 2. Creating a NetView Bridge Dispatcher Profile\" on page 8.\n\nWhen initialization is complete, you receive message DWO531I, stating that the NetView Bridge initialization is complete.\n\nStep 2. Starting the Database Servers\n\nAfter you receive message DWO531I, you can start each of your database server copies in accordance with your database server documentation. Consult the documentation for your database server.\n\nIf copies of the database server are started before initialization of the autotask has completed, unpredictable results can occur.\n\nIf you have followed the procedures outlined in this book and your database server documentation, NetView Bridge is now operational.\n\nStep 3. Starting the NetView Bridge Remote Dispatcher\n\nBefore you can start the remote dispatcher, you must initialize the high performance transport task, DSIIHPDST. Refer to Tivoli NetView for OS/390 Installation Configuring Additional Components for information on defining the high performance transport. When initialization is complete, you receive message DSI633I.\n\nTo access NetView Bridge remotely, you must first start the NetView Bridge remote dispatcher by issuing the following command on both the resident and remote NetView systems:\n\nAUTOTASK OPID=REMOPER\nWhere REMOPER is the operator ID that you assigned in [Step 1. Adding an Operator ID for the Remote Dispatcher Autotask” on page 11].\n\nThis command starts REMOPER as a NetView autotask and automatically executes the REMOTEBR command as specified in the profile you created in [Step 2. Creating a NetView Bridge Remote Dispatcher Profile” on page 11].\n\nAutomating the Startup of NetView Bridge and NetView Bridge Remote Access\n\nYou can customize your CNMSTYLE member so that the AUTOTASK commands described in [Step 1. Starting NetView Bridge” on page 79] and [Step 3. Starting the NetView Bridge Remote Dispatcher” on page 79] execute automatically when the NetView program is started.\n\nAutomating the Startup of a Database Server\n\nIf your database server is started by an MVS operator command, you can customize your NetView program so that the command to start your database server is automatically issued when the NetView Bridge dispatcher has finished initializing. One method of doing this is to add a NetView automation table entry that traps NetView Bridge message DWO531I and invokes the NetView MVS system operator command from the NetView program.\n\nFor information about the NetView automation table, refer to [The Automation Table” in Tivoli NetView for OS/390 Automation Guide]. For information on issuing the NetView MVS command, refer to the online help.\n\nTo successfully automate the startup of a database server, you must ensure that the correct NetView automation table is active, and that the NetView MVS command environment is active.\n\nIf you are using MVS EMCS consoles, two requirements must be met before a NetView MVS command executes:\n\n- Ensure that the task is allowed to obtain a console. You do not need to make an entry in CONSOLxx, but verify that the console name is not already in use.\n- Make sure that the extended console is not blocked by Security Access Facility/Resource Access Control Facility (SAF/RACF).\n\nIf you are using subsystem consoles, several requirements must be met before a NetView MVS command executes:\n\n- The NetView subsystem address space must be started from MVS. This is usually done before starting the primary NetView address space. You receive message CNM563I if the NetView subsystem address space is not active when you issue a NetView MVS command.\n- The NetView subsystem address space router task CNMCSSIR must be started. The NetView default is to start this task. Refer to sample CNMSTYLE for more information.\n\nMessage DSJ530I indicates that task CNMCSSIR is started and ready.\n\n- If you attempt to start CNMCSSIR when the NetView subsystem address space is not started, message CNM563I is issued and CNMCSSIR waits until the NetView subsystem becomes active. If you attempt to issue a NetView MVS command when CNMCSSIR is not active, message CNM5601 is issued.\n• The NetView MVS command assigns an MVS subsystem console ID to each issuing task. Ask the system programmer to verify that a sufficient number of subsystem consoles has been defined to MVS. For each additional subsystem console that is to be defined, have your system programmer add an entry in SYS1.PARMLIB (CONSOLxx) that is similar to the following:\n\nCONSOLE DEVNUM(SUBSYSTEM), AUTH(ALL)\n\nReinitialize your MVS system before the additional console definitions become effective.\nChapter 6. Adjusting NetView Bridge to Optimize Performance\n\nThis chapter describes some considerations for optimizing the performance of NetView Bridge in your system. Many performance issues are unique to the configuration of your host system. However, certain usage conventions can help you make the best use of NetView Bridge, regardless of your system configuration.\n\nNetView Bridge is an automation tool, but is not intended to support vast quantities of data transport or migration. For this reason, you might want to decrease the amount of data in a given transaction, and the number of transactions in general.\n\nThe following sections:\n• Describe some of the methods for reducing NetView Bridge traffic.\n• Give examples of both desirable and undesirable traffic.\n• Describe methods of handling large amounts of traffic when it becomes necessary to do so.\n\nLimiting Traffic Across the Bridge\n\nYou can improve the performance of NetView Bridge by using discretion in choosing what to send across the bridge. One method for limiting traffic is to use NetView automation table command list processing to reduce traffic. For detailed information on how to use the automation table, see Autotasks in Tivoli NetView for OS/390 Automation Guide.\n\nDesirable traffic can be characterized as follows:\n• A single transaction that represents multiple units of data. One message stating that several transactions were completed is preferable to individual messages for each occurrence.\n• Carefully controlled volumes of traffic. You might find that simply giving some forethought to what you allow across the bridge significantly reduces the amount of normal traffic. Reduce traffic by selectively querying the database rather than using database dumps.\n\nUndesirable traffic can be characterized as follows:\n• Large amounts of data that might include:\n – A high volume of repetitious data\n – Numerous single transactions that approach 31K in size\n – Transportation of unimportant data\n• Any combination of high volume plus large, single transactions\n• Any single transaction that results in long (approaching 31K) replies.\n\nUsing Multiple Copies of Database Servers to Increase Throughput\n\nIf you have made every attempt to reduce unnecessary, or undesirable, traffic, and the demands on a NetView Bridge are increasing, you can increase throughput by adding copies of database servers to a NetView Bridge server set.\n\nConsult the documentation for your database server for instructions on how to create more copies of a server.\n\nNote: Adding too many servers can, at some point, begin to degrade NetView Bridge performance, because large numbers of servers begin to compete for...\naccess to the database. If you experience such degradation of performance, you should experiment with your number of servers to achieve optimum performance in your environment.\n\n### Adjusting Queue Limits\n\nWhen a backlog of transactions occurs, transaction requests are held in the HOLD queue of the program-to-program interface. The NetView Bridge RTRINIT command contains the HQUEUEL operand that sets the size of this queue.\n\nTransactions can back-up in the hold queue. If you are experiencing a problem of this nature, or if you are concerned about your storage use, you can use the DISBQL command to display the number of buffers on the hold queue. You can also adjust the HQUEUEL value of the RTRINIT command to a size that better suits your performance needs. You can use the SETBQL command to reset the size of the queues. See NetView online help for more information on the DISBQL and the SETBQL command.\n\nIf any queue limits are reached, message DWO550I is issued, and all subsequent transaction requests received while this condition exists are terminated.\n\n### Saving Storage\n\nIf the NetView Bridge dispatcher or remote dispatcher is infrequently used, consider changing RES=Y to RES=N on all command model statements to save storage. Refer to “Coding RES=N on Command Model Statements” in the *Tivoli NetView for OS/390 Tuning Guide* for more information on coding RES=N to save storage.\nChapter 7. Reporting a Problem to Tivoli®\n\nThis chapter explains how to describe a problem to Tivoli Customer Support so that a resolution can be found and returned to you. For more information on reporting a problem, refer to “Documenting and Reporting Problems” in the Tivoli NetView for OS/390 Diagnosis Guide.\n\nCollecting Information\n\nGather the following information for all problems, including those for which you cannot identify the problem type:\n\n1. Record any abend or return codes, as well as the name of any files involved in the failure.\n2. Research the scenario leading to the failure. Answer the following questions:\n • What was the first indication of the problem?\n • What were you trying to do?\n • What did you expect to happen?\n • What actually happened?\n • Has the function worked before?\n • Can you re-create the problem?\n3. Note any unique information about the problem or your system, such as:\n • Were other applications running when the problem occurred?\n • Did you modify any of the programs that were running?\n4. Record the operating system, version number, release number, and maintenance level. Note any program temporary fixes (PTFs) or authorized program analysis reports (APARs) that have been applied to the operating system or the NetView program.\n5. Print a copy of the NetView trace log.\n\nNote: The NetView trace log is of use only if NetView command list language or REXX code was executing at the time of the failure.\n\n6. Print a copy of the NetView HLL remote interactive debugger (RID) and first failure data capture (FFDC) trace logs. These tools are supported by NetView Bridge service routines CNMSNDT and CNMGETP. For more information, refer to the Tivoli NetView for OS/390 Customization: Using PL/I and C and Tivoli NetView for OS/390 Diagnosis Guide.\n\nNote: The NetView Bridge server support API service routines maintain an eight-entry, continuously wrapping trace area. This 48-byte area is referred to as the first failure data capture area (FFDCA). Its name is HLBFFDCA and it is located in the DSIBPHEL control block (for PL/I), and the DSIBCHLB control block (for C).\n\nYou can print the contents of this trace area during job execution by including the appropriate PL/I or C print statements in your service routines. If a failure occurs, this area identifies the server support API module that was running at the time of failure.\n\n7. Print a copy of the system log. The system log is a data set or file in which job-related information, operational data, descriptions of unusual activity, commands, and messages can be stored.\n\n8. Provide a copy of any command list, REXX routine, or HLL service routine (if applicable) that was executing at the time of the problem.\nThe Tivoli Customer Support representative helps you gather additional information, if needed.\n\n### Calling Tivoli Customer Support\n\nTivoli Customer Support is the first point of contact for NetView Bridge customers who need help with a program problem after installation is complete. When you call Customer Support, a dispatcher asks for customer identification information, such as your account name, access code, and program license number. The dispatcher determines the type of help that you need, assigns a problem number, and places your call on a queue for a Customer Support representative.\n\n### Searching the Software Support Database for a Possible Solution\n\nThe Tivoli Customer Support representative asks you to describe your problem. The representative uses this information to search RETAIN®, a Tivoli database containing symptoms and resolutions, for known problems and information on problems currently under investigation. The representative may ask for additional information that might help in the search.\n\nIf a similar problem description is found, then a solution is probably available. If you have the Information/Access Tivoli licensed program, or IBMLINK, you can search the RETAIN database for similar problems.\n\nIf the search does not produce a solution, the representative makes sure that you have the necessary information to discuss the problem with a systems specialist. Your call is then placed on a queue for a systems specialist.\n\n### Opening an APAR with Tivoli Customer Support\n\nIf a solution cannot be found and if the problem appears to be a new one, the representative may enter an authorized program analysis report (APAR) into the Tivoli Customer Support database.\n\nThe systems specialist assigns a number to your APAR. If you are asked to send documentation about your problem to Tivoli, write this APAR number in the upper right corner of each piece of documentation you send.\n\nBoth the APAR and other helpful documentation allow the systems specialist to examine the problem in greater detail to develop a solution. If this solution is a coding change, it is put into a program temporary fix (PTF) and sent to you. All information about the solution is entered into the RETAIN database. This procedure keeps the database current with problem descriptions and solutions and makes the information available for future RETAIN searches.\nAppendix A. NetView Bridge Initialization Commands\n\nThis appendix documents general-use programming interface and associated guidance information.\n\nThis appendix describes the NetView Bridge initialization command (RTRINIT) and the NetView Bridge remote access initialization command (REMOTEBR).\n\nRTRINIT Command\n\nNetView Bridge uses the RTRINIT command to activate the interface between a NetView autotask and a specific set of database servers. This command must be executed under an autotask. See “Step 1. Adding an Operator ID for the Dispatcher Autotask” on page 8 for instructions on creating this autotask.\n\nThe RTRINIT command is driven by the profile of a NetView autotask. This autotask serves as the interface between a NetView autotask and a specific set of database servers, and defines three user-provided queue names to the program-to-program interface. These queues are the output queue, to which the database servers send all their output, the ready queue, which contains ready tokens indicating which database servers are available, and the hold queue, which holds requests when no database servers are available. A bridge dispatcher executes the NetView Bridge command RTRINIT to establish the NetView Bridge environment. For more information on the PPI, refer to “Understanding the NetView Program-to-Program Interface” in the Tivoli NetView for OS/390 Application Programmer’s Guide.\n\nNote: The operands described in the following syntax are positional and must be placed in the order shown.\n\nThe format for the RTRINIT command is:\n\n```\nRTRINIT --hqueue,rqueue,oqueue,hqueue\n```\n\nWhere:\n\n- **hqueue**\n \n Is the name of the hold queue. A PPI queue is created to save transactions that have not been dispatched to a database server. This 1- to 8-character field is required and can contain uppercase alphabetic characters, numeric characters, or $, %, &, @, and #.\n\n- **rqueue**\n \n Is the name of the ready queue. A PPI queue is created to save the READY tokens generated by the database servers. This 1- to 8-character field is required and can contain uppercase alphabetic characters, numeric characters, or $, %, &, @, and #.\n\n- **oqueue**\n \n Is the name of the output queue. A PPI queue is created to receive transaction replies and control messages from the database servers. This queue has the same name as the tioutq queue name defined in the CNMETIN service routine.\nof the server support API. For more information on the service routine CNMETIN, see \"Appendix C. Server Support API Commands and Service Routines\" on page 107.\n\nThis 1- to 8-character field is required and can contain uppercase alphabetic characters, numeric characters, or $, %, &, @, and #.\n\n**hqueue**\n\nDefines the limit of the HOLD queue to the PPI. This parameter is required, and must be an integer. Its value must be between 50 and 2000 inclusive. See [Adjusting Queue Limits](#) on page 84 for more information on the implications of the value you assign to this limit.\n\n### Usage Notes\n\nYou must execute the RTRINIT command to activate NetView Bridge. If you attempt to route transactions through the bridge without issuing the RTRINIT command, you receive several error messages. Repeat attempts do not produce error messages, however.\n\nIf you issue the RTRINIT command from a NetView command list, do not use the ampersand (&) as part of a queue name. The ampersand is defined as a special character in the NetView command list language.\n\nWhen the RTRINIT command issues an error message, the autotask in which the command is running is still active. You can do one of the following:\n\n- Recycle the autotask as follows:\n 1. Issue the following command:\n \n ```\n EXCMD autotaskname, LOGOFF\n ```\n \n to log off the autotask from the NetView operator terminal.\n 2. Correct the error.\n 3. Issue the following command:\n \n ```\n AUTOTASK OPID=autotaskname\n ```\n \n to bring up the autotask.\n\n- Correct the error and rerun the command by issuing the following:\n\n ```\n EXCMD autotaskname, RTRINIT hqueue,rqueue,oqueue,hqueue\n ```\n\nfrom the NetView operator terminal.\n\nOnce the RTRINIT command completes successfully, the task may be terminated by severe errors. You can then recycle the autotask as follows:\n\n1. Correct the error.\n2. Issue `AUTOTASK OPID=autotaskname`.\n\nThe queue limit for `rqueue` and `oqueue` is 2000. If this limit is exceeded, NetView Bridge message DWO550I is issued.\n\nIf the queue limit for `hqueue` (the hold queue) is exceeded, further transactions are discarded, and NetView Bridge message DWO550I is issued. You can increase the limit by changing the value specified by `hqueue` in the RTRINIT command and issue `AUTOTASK OPID=autotaskname` to bring up the autotask.\n\nIn cases where the NetView subsystem address space is down, use the same subsystem interface procedure to bring it up. If you use a different subsystem interface procedure, recycle the autotask.\nReturn Codes\n\nThe return codes for the RTRINIT command are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>00</td>\n<td>The command completed successfully.</td>\n</tr>\n<tr>\n<td>20</td>\n<td>The command did not complete successfully.</td>\n</tr>\n</tbody>\n</table>\n\nREMOTEBR Command\n\nThe REMOTEBR command enables the NetView Bridge remote dispatcher to register as an HP application on the high performance transport API. This command is driven by the profile of the NetView Bridge remote dispatcher autotask. The autotask must be running in both the remote NetView program that is sending transactions and receiving replies, and in the resident NetView program in which the database server resides. Only one autotask in each NetView program can issue this command at a time. Consecutive invocations of this command by other tasks results in message DWO534I being issued.\n\n**Note:** Although you can execute REMOTEBR from the same autotask NetView Bridge is using to communicate with a local database server, this setup is not recommended. Issue the REMOTEBR command from a new autotask.\n\nSee [Step 1. Adding an Operator ID for the Remote Dispatcher Autotask” on page 11](#) for instructions on creating this autotask.\n\nThe syntax for the REMOTEBR command is:\n\n```\nREMOTEBR\n```\n\nUsage Notes\n\nWhen the REMOTEBR command issues an error message, the autotask in which it is running is still active. You can do one of the following:\n\n- Recycle the autotask as follows:\n 1. Issue the following command:\n ```\n EXCMD autotaskname, LOGOFF\n ```\n to log off the autotask from the NetView operator terminal.\n 2. Correct the error.\n 3. Issue the following command:\n ```\n AUTOTASK OPID=autotaskname\n ```\n to bring up the autotask.\n- Correct the error and rerun the command by issuing the following command:\n ```\n EXCMD autotaskname, REMOTEBR\n ```\n from the NetView operator terminal.\nOnce the REMOTEBR command completes successfully, the task can be terminated by severe errors. You can then recycle the autotask as follows:\n1. Correct the error.\n2. Issue AUTOTASK OPID=autotaskname.\n\nReturn Codes\n\nThe return codes for the REMOTEBR command are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>The command completed successfully.</td>\n</tr>\n<tr>\n<td>20</td>\n<td>The command was not completed successfully.</td>\n</tr>\n</tbody>\n</table>\nAppendix B. NetView Bridge Requester API Commands and Service Routines\n\nThis appendix documents general-use programming interface and associated guidance information.\n\nThis appendix describes REXX commands, NetView command lists, and HLL service routines associated with the NetView Bridge Requester API part of NetView Bridge. The procedures for programming the NetView Bridge Requester API are in “Chapter 4. Writing a NetView Bridge Command Procedure Using the NetView Bridge Requestor API” on page 55. Use the reference information in this appendix as a guide for creating your own NetView Bridge command procedures.\n\nREXX and NetView command list commands are listed (by function), and described in detail, beginning with \"TRANSND—Send Transaction Request to Database Server\".\n\nHLL service routines are listed by name and described in detail, beginning with \"CNMSNDT (CNMSENDTR)—Send Transaction Request to Database Server\" on page 96. Each service routine has an explanation of its use and syntax, as well as complete descriptions of each field and operand.\n\nREXX and NetView Command List NetView Bridge Commands\n\nYou can issue two commands, the TRANSND and TRANRCV commands, from the NetView interface using REXX routines or NetView command lists to request transactions and process the results.\n\nThis section describes these commands and their operands. Figure 16 on page 58 shows a sample REXX EXEC that uses the TRANSND and TRANRCV commands. Figure 17 on page 62 shows a sample NetView command list that uses the TRANSND and TRANRCV commands. These samples assume that the command procedure is being run under an Operator Station Task (OST). Running under the primary program operator interface task (PPT) is not recommended because you cannot wait for transaction replies.\n\nTRANSND—Send Transaction Request to Database Server\n\nThe TRANSND command is used to build and send a transaction request to the transaction processor of a database server. The TRANSND command can run only under an operator station task (OST) or a primary POI task (PPT). Running under the PPT is not recommended because you cannot wait for transaction replies. It cannot run under a NetView-NetView task (NNT).\n\nAfter you send a remote transaction using the high performance transport API, some parameter information is saved. In the event of an error in the send, this information must be retrieved for posting to message DWO546I. Initially information is saved for 2 minutes. However, you can adjust this time by issuing DEFAULTS NOREPLY = x (where x is the time in seconds). If the queue that holds the information is discarded before the error message is received, UNKNOWN is displayed in the field of the unknown parameter in the DWO546I error message.\n\nThe syntax for the TRANSND command is:\nTRANSND\n\n\\[ \\text{TRANSND} \\text{ TRANSID} = \\text{transid} , \\text{TRTYPE} = \\{ \\text{QERR} | \\text{QALL} | \\text{QNON} \\} \\]\n\nWhere:\n\n**TRANSID** = \\text{transid} \nIs the name of the transaction to be executed. TRANSID is a required operand that must be 1—8 alphanumeric characters.\n\n**TRTYPE** = \\{ QERR | QALL | QNON \\}\nIndicates the type of transaction to be performed. TRTYPE is a required operand, and it must be entered as uppercase characters. The following are the possible values:\n\n- **QERR** Indicates that this is a request transaction, but only error responses are to be returned to the requesting task.\n- **QALL** Indicates that this is a request transaction, but all operational and error response data is to be returned to the requesting task.\n- **QNON** Indicates that this is a request transaction, but that no responses (error condition or operational) are to be returned to the requesting task.\n\n**DESTNET** = \\{ * | \\text{destnet} \\}\nIs an optional 1- to 8-character (uppercase) field that identifies the ID of the network where the bridge dispatcher, server address space, and target database reside. If you do not specify this field, or if you specify DESTNET = *, VTAM determines the network ID based on the LU name of the remote node. If two nodes in two different networks have the same LU name, VTAM will sometimes locate one and sometimes locate the other, depending on the active configuration.\n\n**DESTDOM** = \\text{destdom}\nIs an optional 1- to 8-character (uppercase) field that identifies the ID of the domain where the bridge dispatcher, server address space, and target database reside. If you do not specify this field, it defaults to the local network ID.\n\n**DESTTASK** = \\text{desttask}\nIs a required 1- to 8-character (uppercase) field that identifies the task ID of the bridge dispatcher autotask that manages the server that processes the transaction.\n\n**VOCAB** = \\text{vocab}\nIs an optional operand that specifies the name of the context used to interpret the operand names in the request. The context is defined by the server. (See the documentation for your particular server for details on vocabulary restrictions.) This is a mechanism for converting operand names that are\nrecognized by NetView to names that can be recognized by the target\ndatabase. The value of this operand, if specified, is 1–8 alphanumeric\ncharacters. If you omit this operand, the default context defined by the target\ndatabase is used.\n\n**CORR=**<br>\nIs an optional operand that can be used to associate a response with any data\nthat was kept by the requestor at the time the request transaction was issued. If\nyou specify this operand, the value must be 1–8 alphanumeric characters. If\nyou do not specify a value, an 8-character alphanumeric value is generated by\nthis command and returned in a variable named CORREL in the format\nDDHHMMSS, where:\n\n- **DD** is the day\n- **HH** is the hour\n- **MM** is the minute\n- **SS** is the number of seconds\n\nThe invoker can use the value generated in the same manner that it can use a\nuser-supplied value.\n\n**PARMVAR=**<br>\nIs an optional operand you can use to specify the name of a REXX or NetView\ncommand list variable. The value of this variable is a list of names of operands\n(delimited by blanks) to be sent with the request. The values of the operands\nlisted in PARMVAR are obtained by treating each name specified as the name\nof a REXX or NetView command list variable. The value of the variable is the\nvalue of the operand.\n\nREXX limits the variable name length to 31 characters, and the NetView\ncommand list language limits the variable name length to 11 characters. All\nalphabetic characters in this name must be entered as uppercase characters.\n\nIf a variable with the name you specified does not exist, the value of the\noperand is assumed to be null (length of 0).\n\nIf a REXXX variable is a stem with an index (for example, An where n is\nnumeric), the operand A is assumed to be an array (it has subparameters) with\nindexes 1 through n. The number of indexes (size of the array) must be\nindicated in A.0. The stem variable must be represented in the PARMVAR in the\nform of *variable-name* operand (for example, A.). This form is used when\nhandling lines of text in which each line of text is an entry in the array. The\nNetView command list language does not provide the array-type variable.\n\nNetView command list language variable names are listed in PARMVAR as the\nname of the variable without the leading ampersand (&). All parameter values\nare designated to have a value-type indicator of X'00EE' in the generated\ntransaction showing that it is an EBCDIC string.\n\n**Usage Notes**\n\nThe maximum length of the transaction operands and their values that can be\nspecified on the TRANSND command is approximately 31K. A transaction request\nthat is larger than the maximum length is rejected, and NetView Bridge message\nDWO568I is issued.\nReturn Codes\n\nThe return codes for this command are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n<tr>\n<td>4</td>\n<td>Processing error encountered—no request sent. Error message was issued.</td>\n</tr>\n</tbody>\n</table>\n\nTRANRCV—Receive a Transaction Reply\n\nThe TRANRCV command is issued by a REXX or NetView command list after that command list has trapped message DWO548I. The TRANRCV command contains the operands of a transaction reply.\n\nThe syntax for the TRANRCV command is:\n\n```\nTRANRCV\n```\n\nWhere:\n\n- **PARMVAR=varname**\n - Is an optional operand that specifies the name of a REXX or NetView command list variable. The value of this variable is a list of names of operands, delimited by blanks, returned with the reply. The parameters are returned from the transaction processor. The parameter values can be obtained by parsing the PARMVAR variable.\n\nThe name of the parameter from the transaction becomes the name of the variable as long as it satisfies the restrictions for variable names specified for the language. The value of the parameter becomes the value of the variable.\n\nNetView command list language variable names are stored in the PARMVAR variable without the ampersand.\n\nVariable names that are too long for the language are truncated after the maximum number of characters allowed is reached. REXX limits variable names to 31 characters, and the NetView command list language limits variable names to 11 characters.\n\nIf a parameter is actually an array, the data is stored in different variable names. How this data is stored depends on whether REXX or the NetView command list language is used. If REXX is used, variables are named A.n, where A is the name of the parameter and n is the index into the array. A.0 contains the number of entries in the array. If a NetView command list is used, no more than the first 9 characters of the parameter name are used, followed by the two digits of the index (an index value of 1 is put into the name as 01, and so on).\n\nWhen a transaction reply returned from a database server is longer than 31K, it is truncated to 31K and sent to the NetView Requester API. The truncation is indicated to the API requester by a CNM_TRUNCATION parameter with the\nvalue YES. The CNM_TRUNCATION parameter is the last parameter returned in the PARMVAR if the truncation occurred in a transaction reply.\n\nThe following variable names for the header parameters will always be set by this command:\n\n**RPTRANSID**\nIs a 1- to 8-character field that identifies the received transaction reply.\n\n**RPTRTYPE**\nIs a 4-character field that identifies the type of transaction that is being received.\n\n**RPDESTNET**\nIs a 1- to 8-character field that identifies the destination network ID of the received transaction. This value should be the network ID of the NetView in which this command is running.\n\n**RPDESDOM**\nIs a 1- to 8-character field that identifies the destination domain ID of the received transaction. This value should be the domain ID of the NetView in which this command is running.\n\n**RPDESTSK**\nIs a 1- to 8-character field that identifies the destination task ID of the received transaction. This value should be the NetView task ID in which this command is running.\n\n**RPORIGNET**\nIs a 1- to 8-character field that identifies the originating network ID of the received transaction.\n\n**RPORIGDOM**\nIs a 1- to 8-character field that identifies the domain ID of the received transaction reply.\n\n**RPORIGTSK**\nIs a 1- to 8-character field that identifies the NetView autotask that serves the database server that sent this transaction reply.\n\n**RPCORREL**\nIs a 1- to 8-character correlator field from the transaction reply received.\n\n**RPVOCAB**\nIs a 1- to 8-character field that contains the name of the context used to interpret the parameters in the transaction reply.\n\n**RPRESPCODE**\nIs an 8-character field that contains the response code value that was returned with the transaction reply.\n\n**Note:** These variables do not appear in the variable identified with the PARMVAR parameter. They are individually set by the TRANRCV command.\n\n### Return Codes\n\nThe return codes for this command are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n<tr>\n<td>Return Code Value</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-------------------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>2</td>\n<td>Transaction parameter name or value is truncated—processing continues.</td>\n</tr>\n<tr>\n<td>4</td>\n<td>Processing ended due to failure—error message is issued.</td>\n</tr>\n</tbody>\n</table>\n\n### NetView Bridge HLL Service Routines\n\nYou can issue two commands, CNMSNDT and CNMGETP, from C and PL/I programs using the NetView Bridge Requester API. These commands invoke service routines and enable you to request transactions and to process the results from NetView.\n\nThis section describes these commands and their operands. Figure 18 on page 66 shows a sample PL/I program that uses the CNMSNDT and CNMGETP commands. Figure 19 on page 71 shows a sample C program that uses the CNMSNDT and CNMGETP commands. These samples assume that the command procedure is being run under an Operator Station Task (OST). Running under the primary program operator interface task (PPT) is not recommended because you cannot wait for transaction replies. Also, VM and VSE do not support PL/I or C.\n\nFour types of parameters can be passed to the NetView Bridge Requester API service routines. They are:\n- Pointer variables\n- Integer variables\n- Fixed-length character strings\n- Varying-length character strings\n\nThe NetView Bridge Requester API service routines require you to declare, initialize, and pass parameters to the API service routines according to PL/I or C programming language specifications. For more information on these specifications, refer to OS PL/I Version 2 Programming: Language Reference and Coding Your PL/I Program: Environment, Interfaces, and Restrictions or Coding Your C Program: Interfaces and Restrictions in Tivoli NetView for OS/390 Customization: Using PL/I and C.\n\n### CNMSNDT (CNMSENDTR)—Send Transaction Request to Database Server\n\nThe CNMSNDT service routine sends a transaction request to the database server.\n\nAfter you send a remote transaction using the high performance transport API, some parameter information is saved. In the event of an error in the send, this information must be retrieved for posting to message DWO546I. Initially information is saved for two minutes. However, you can adjust this time by issuing DEFAULTS NOREPLY = x (where x is the time in seconds). If the queue that holds the information is discarded before the error message is received, UNKNOWN is displayed in the field of the unknown parameter in the DWO546I error message.\n\nThe syntax for the CNMSNDT command is:\nPL/I CALL FORMAT:\n\nCALL CNMSNDT(hlbptr,sttransid,sttrtype,stdestnet,stdestdom,stdesttask,\nstvocab,stcorr,stparms)\n\nPL/I MACRO FORMAT:\n\nCNMSENDTR TRANSID(sttransid) TRTYPE(sttrtype) DESTNET(stdestnet)\nDESTDOM(stdestdom) DESTTASK(stdesttask) VOCAB(stvocab) CORR(stcorr)\nPARMS(stparms)\n\nC INVOCATION:\n\nvoid Cnmsndt(char * sttransid, char * sttrtype, char * stdestnet, char * stdestdom, char\n* stdesttask, char * stvocab, char * stcorr, Dsicprm ** stparms)\n\nWhere:\n\nhlbptr\nIs a 4-byte pointer field containing the address of the HLL control block that was\npassed to the HLL program (DSIPHLB for PL/I or DSICHLB for C). This control\nblock is described in \"Coding Your PL/I Program: Environment, Interfaces, and\nRestrictions\" and \"Coding Your C Program: Interfaces and Restrictions\" in Tivoli\nNetView for OS/390 Customization: Using PL/I and C\n\nsttransid\nIs a fixed-length 8-character operand that contains the name of the transaction\nto be executed. If this field contains fewer than 8 characters, it must be\nleft-justified and padded with blanks. No embedded blanks are allowed in this\nvalue.\n\nsttrtype\nIs a 4-character operand that indicates the type of transaction processing to be\nperformed. The database server uses the value specified in this field to\ndetermine what response is to be returned for this request. The following are\nthe possible values:\n\nQERR Indicates that this is a request transaction, but only error responses are\nto be returned to the requesting task.\n\nQALL Indicates that this is a request transaction, but all operational and error\nresponse data is to be returned to the requesting task.\n\nQNON Indicates that this is a request transaction, but no responses (error\ncondition or operational) are to be returned to the requesting task.\n\nstdestnet\nIs a fixed-length 8-character field that identifies the network that contains the\nbridge dispatcher, the server address space, and the target database. If this\nvalue is fewer than 8 characters, it must be left-justified and padded with\nblanks. If the value of the parameter is blanks or *, this field defaults to the\nnetwork ID determined by VTAM based on the domain name specified in\nstdestdom. If two nodes in two different networks have the same LU name,\nVTAM will sometimes locate one and sometimes locate the other, depending on\nthe active configuration.\n\nstdestdom\nIs a fixed-length 8-character field that identifies the domain that contains the\nbridge dispatcher, the server address space, and the target database. If this\nvalue is fewer than 8 characters, it must be left-justified and padded with blanks. If the value of the parameter is blanks, this field defaults to the local domain ID.\n\n**stddesttask**\n\nIs a fixed-length 8-character field that identifies the task ID of the autotask that serves the database server. This autotask processes the transaction. If this value is fewer than 8 characters, it must be left-justified and padded with blanks. No embedded blanks are allowed in this value.\n\n**stvocab**\n\nIs a fixed-length 8-character field that identifies the context that is used to interpret the parameter names in the transaction. If this field is left blank, the default context is used. The default context is defined in your database server.\n\n**stcorr**\n\nIs a fixed-length 8-character field that associates a response with any data that was kept by the requestor at the time the transaction was issued. If no correlator is required, set the value of this field to blanks.\n\n**stparms**\n\nIs a field that contains a pointer to a linked list of parameter blocks. If no parameters are to be sent to a transaction, set this field to either a C null (X'00000000') or a PL/I null (X'FF000000').\n\n**Note:** NetView provides the mapping of the parameter block in PL/I and C under the include file names DSIPPRM (for PL/I) and DSICPRM (for C). These files are included by DSIPLI and DSIC. Therefore, you need to include DSIPLI or DSIC in your program.\n\nThe following is the structure of a parameter block:\n\n**prmlink**\n\nContains a pointer to the next parameter block in the chain. If this is the last parameter in the chain, set this field to either a C null (X'00000000') or a PL/I null (X'FF000000').\n\n**prmnaml**\n\nContains a halfword binary integer that defines the length of the parameter name. This value must be in the range 1–31.\n\n**prmname**\n\nIs a fixed-length 31-byte field containing the name of the parameter.\n\n**prmindex**\n\nContains a signed halfword binary integer that identifies the index value within a parameter that happens to be an array. A value of minus 32,767 is interpreted to mean that this parameter is not an array. Parameter arrays are intended to handle multiple values for a given parameter (for example, lines of text in a problem description).\n\n**prmtype**\n\nContains a halfword binary integer that identifies the type of parameter. This field has two possible values:\n\n- X'00EE'\n - Indicates that the parameter value is an EBCDIC character string.\n\n- X'00BB'\n - Indicates that the parameter value is a binary integer.\nprmleng\nContains a halfword binary integer that identifies the length of the parameter value. The value of this field must be less than 31,000.\n\nIf the parameter type value (prmtype) is X'00EE', indicating that this is an EBCDIC character string, this field contains the length of the character string (in number of bytes). If the parameter type value is X'00BB', indicating that this is a binary integer, this field contains the length of the fixed binary integer variable, which is used to carry the binary integer. For example:\n- In PL/I, the length is 4 for a FIXED BIN(31,0) variable, or 2 for a FIXED BIN(15,0) variable.\n- In C, the length is 4 for a long integer variable, or 2 for a short integer variable.\n\n**Note:** The actual maximum length of any parameter value depends on the length of all fields in the transaction. The maximum length of any transaction is 31K. If the transaction request exceeds the maximum length the transaction is rejected. For complete details on calculating the size of a transaction, see \"Understanding Transaction Size Limitations\" on page 55.\n\nprmptr\nContains a pointer to the value of the parameter. If you do not specify a value, set this field to either a C null (X'00000000') or a PL/I null (X'FF000000').\n\n**Return Codes**\n\nThe return codes for this command are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CNM_GOOD</td>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n<tr>\n<td>CNM_BAD_INVOCATION</td>\n<td>4</td>\n<td>Nonzero return code.</td>\n</tr>\n<tr>\n<td>CNM_NO_STORAGE</td>\n<td>24</td>\n<td>Storage allocation failure.</td>\n</tr>\n<tr>\n<td>CNM_NOT_IN_ASYNC</td>\n<td>44</td>\n<td>Deregistration unsuccessful. Issued from an exit.</td>\n</tr>\n<tr>\n<td>CNM_BAD_TIMEOUT</td>\n<td>56</td>\n<td>Time-out value is not valid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_LENGTH</td>\n<td>88</td>\n<td>MDS_MU length is not valid.</td>\n</tr>\n<tr>\n<td>CNM_TASK_INACTIVE</td>\n<td>220</td>\n<td>DS16DT task is inactive.</td>\n</tr>\n<tr>\n<td>CNM_REQ_TOO_LONG</td>\n<td>288</td>\n<td>The transaction request generated exceeds 31K.</td>\n</tr>\n<tr>\n<td>CNM_BAD_TASK</td>\n<td>292</td>\n<td>Invalid task type. This service routine can be invoked only under an OST or a PPT.</td>\n</tr>\n<tr>\n<td>CNM_BAD_TRAN_HDR</td>\n<td>296</td>\n<td>One of the transaction header parameters contains an invalid value.</td>\n</tr>\n<tr>\n<td>CNM_PROCESSING_ERROR</td>\n<td>300</td>\n<td>A severe error condition was encountered when the service routine attempted to build the transaction request.</td>\n</tr>\n<tr>\n<td>CNM_BAD_DATA_TYPE</td>\n<td>400</td>\n<td>Data type is not valid.</td>\n</tr>\n<tr>\n<td>Return Code Name</td>\n<td>Value</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>--------------------------</td>\n<td>---------</td>\n<td>--------------------------------------------------</td>\n</tr>\n<tr>\n<td>CNM_BAD_DATA</td>\n<td>404</td>\n<td>DATA missing or not valid.</td>\n</tr>\n<tr>\n<td>CNM_SAME_APPL</td>\n<td>408</td>\n<td>MS application cannot send to itself.</td>\n</tr>\n<tr>\n<td>CNM_OAPPL_NOT_REG</td>\n<td>416</td>\n<td>MS application is not registered.</td>\n</tr>\n<tr>\n<td>CNM_BAD_SAPPL</td>\n<td>420</td>\n<td>Operations management served application is not registered.</td>\n</tr>\n<tr>\n<td>CNM_BAD_UOW</td>\n<td>424</td>\n<td>UOW missing or not valid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_RTI</td>\n<td>428</td>\n<td>RTI missing or is invalid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_OAN</td>\n<td>432</td>\n<td>OAN missing or is invalid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_DAN</td>\n<td>436</td>\n<td>DAN missing or is invalid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_OAPPL</td>\n<td>440</td>\n<td>Origin application name is invalid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_DNETID</td>\n<td>444</td>\n<td>Destination network ID missing or is invalid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_DLU</td>\n<td>448</td>\n<td>Destination LU name missing or is invalid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_DAPPL</td>\n<td>452</td>\n<td>Destination application name missing or is invalid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_OII</td>\n<td>456</td>\n<td>OII in RTI does not match TVBOPID.</td>\n</tr>\n<tr>\n<td>CNM_BAD_REPLY</td>\n<td>460</td>\n<td>Reply is invalid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_MUTYPE</td>\n<td>464</td>\n<td>Bad MUTYPE given.</td>\n</tr>\n<tr>\n<td>CNM_BAD_SYNCH</td>\n<td>468</td>\n<td>Bad SYNCH option.</td>\n</tr>\n<tr>\n<td>CNM_BUSY</td>\n<td>472</td>\n<td>User list is full.</td>\n</tr>\n<tr>\n<td>CNM_BAD_MQS</td>\n<td>1000 + X</td>\n<td>MOS failed while sending a transaction request to DESTTASK. X is the return code from DSIMQS.</td>\n</tr>\n<tr>\n<td>CNM_BAD_PUSH</td>\n<td>4000 + Y</td>\n<td>Nonzero return code, Y, from DSIPUSH macro. ¹</td>\n</tr>\n<tr>\n<td>CNM_BAD_CES</td>\n<td>9000 + Y</td>\n<td>Reply command is invalid. Y is the return code from DSICES.</td>\n</tr>\n<tr>\n<td>CNM_BAD_TRAN_PARM</td>\n<td>22000 + n</td>\n<td>The nth parameter block in the link list pointed to by the stparms field contains an invalid prmnaml, prmleng value, or both.</td>\n</tr>\n</tbody>\n</table>\n\nNote: Receipt of any nonzero return code indicates that the transaction was not sent.\n\n**CNMGETP (CNMGETPPARM)—Get Transaction Reply Parameters**\n\nThe CNMGETP service routine allows you to extract the contents of NetView Bridge message DWO548I during transaction reply processing. It is important that the DWO548I message remain on the queue until CNMGETP is finished extracting the required data.\n\n¹ See [Tivoli NetView for OS/390 Customization: Using Assembler](#) for more information.\nThe syntax for the CNMGETP command is:\n\n**PL/I CALL FORMAT:**\n\nCALL CNMGETP(hlbptr,gpmethod,gpnameh,gpnamep,gpindex,gpdata, gpdatlen,gptype,gpqueue,gpcursor)\n\n**PL/I MACRO FORMAT:**\n\nCNMGETP ARM METHOD(gpmethod) HNAME(gpnameh) PNAME(gpnamep) INDEX(gpindex) DATA(gpdata) LENG(gpdatlen) TYPE(gptype) QUEUE(gpqueue) CURSOR(gpcursor)\n\n**C INVOCATION:**\n\nvoid Cnmgetp(char *gpmethod,char *gpnameh,void *gpnamep, int *gpindex,void *gpdata,int gpdatlen, short *gptype,int gpqueue,int *gpcursor)\n\nWhere:\n\n**hlbpitr**\nIs a 4-byte pointer field containing the address of the HLL control block. This control block is described in [Coding Your PL/I Program: Environment, Interfaces, and Restrictions](#) and [Coding Your C Program: Interfaces and Restrictions](#) in *Tivoli NetView for OS/390 Customization: Using PL/I and C*.\n\n**gpmethod**\nIs a 1-character field that identifies the method to use for retrieving parameters from the transaction reply. It must contain one of the following values:\n\n- **H** Retrieve the transaction header parameter and its value.\n- **P** Retrieve the value of a transaction parameter by specifying the name of the transaction parameter.\n- **N** Retrieve the name and value of the next transaction parameter, and start searching from the position pointed to by GPCURSOR.\n\n**gpnameh**\nIs an 8-character fixed-length field used to identify the transaction header parameter that is being requested. It must be left-justified and padded with blanks. This field is required if you specify H in gpmethod. It is not required if you specify P or N.\n\nThe following names are valid:\n\n- **TRANSID** Specifies that the name of the transaction reply is returned.\n- **CORR** Specifies that the correlator of the transaction reply is returned.\n- **VOCAB** Specifies that the context of parameter names is returned.\n- **TRTYPE** Specifies that a value indicating that this is a transaction reply (RPLY) is returned.\n- **ORIGNET** Specifies that the origin network ID of the transaction reply is returned.\n- **ORIGDOM** Specifies that the origin domain ID of the transaction reply is returned.\nORIGTASK\nSpecifies that the origin task ID of the transaction reply will be returned. The only task ID that is returned is the ID of the server dispatcher autotask.\n\nDESTNET\nSpecifies that the destination network ID of the transaction reply is returned.\n\nDESTDOM\nSpecifies that the destination NetView domain ID of the transaction reply is returned.\n\nDESTTASK\nSpecifies that the destination task ID of the transaction reply will be returned. The value returned should be the NetView task ID under which this routine is running.\n\nRESPCODE\nSpecifies that the response code for the transaction reply is returned.\n\ngpnamep\nIs a 31-character varying-length field with two different uses:\n- When you specify P with gpmethod, this field (on input) must contain the name of the parameter whose value is to be retrieved.\n- When you specify N with gpmethod, this field (on output) is used to receive the name of the retrieved parameter. The search for this parameter begins at the location pointed to by gpcursor. The value of gpcursor is then set to point to the next parameter.\n\nThis field is required if you specify P or N in gpmethod. It is not required if you specify H.\n\ngpindex\nContains a signed 4-byte integer that has two different uses:\n- When you specify P with gpmethod, this field (on input) contains the index value of an array parameter whose value is to be retrieved. You must specify an index value of −32,767 if the parameter is not an array parameter.\n- When you specify N with gpmethod, this field (on output) is used to receive the index value of the retrieved parameter. The search for this parameter begins at the location pointed to by gpcursor. A value of −32,767 is returned if this parameter is not an array type parameter.\n\nThis field is required if you specify P or N in gpmethod. It is not required if you specify H.\n\ngpdata\nIs a varying-length character field containing the value for the parameter being returned.\n\nIf the parameter type value (gptype) is X'00EE', indicating that this is an EBCDIC character string, this field contains the length of the character string in either the PL/I character varying format or the C Dsivarch format. If the parameter type value is X'00BB', indicating that this is a binary integer, this field contains the binary integer value in the following format:\n- The first two bytes indicate the length of the fixed binary integer variable which was used to carry the integer in the transaction reply. For example:\n - In PL/I, the length is 4 for a FIXED BIN(31,0) variable, or 2 for a FIXED BIN(15,0) variable.\nIn C, the length is 4 for a long integer variable, or 2 for a short integer variable.\n\n- The remaining two or four bytes contain the binary integer value.\n\n**gpdlen**\n\nIs a 4-byte integer that specifies the maximum length of **gpdata**.\n\nIf the value specified by **gpdlen** is less than the length of the parameter value to be returned, the truncated parameter value is returned in **gpdata**, and a return code of CNM_DATA_TRUNC is issued. The full length of the parameter value that was truncated is stored in HLBLENG (Hlbleng).\n\nIf the value specified by **gpdlen** is equal to or greater than the length of the parameter value to be returned, and a return code of CNM_GOOD is issued, the length of the returned parameter value is stored in HLBLENG (Hlbleng).\n\n**gptype**\n\nIs a 2-byte integer field containing the type of the parameter value returned in **gpdata**. One of the following values is set when this procedure returns:\n\n- **X'00EE'**\n Indicates that the returned parameter value is an EBCDIC character string.\n\n- **X'00BB'**\n Indicates that the returned parameter value is an integer.\n\nThis field is required if you specify P or N in **gpmethod**. It is not required if you specify H.\n\n**gpqueue**\n\nIs a 4-byte integer field that specifies the queue that holds the DWO548I message containing the transaction reply. For complete details on this queue identifier, see [PL/I High-Level Language Services](#) and [C High-Level Language Services](#) in [Tivoli NetView for OS/390 Customization: Using PL/I and C](#).\n\n**gpcursor**\n\nIs a 4-byte integer field used to keep track of the position in the scan through the transaction. If you specify N, this field must be initialized to a binary zero before the first call to CNMGETP. Use of this field with a nonzero value can cause unpredictable results. This field is updated each time the CNMGETP is called.\n\nThis field is required if you specify N in **gpmethod**. It is not required if you specify H or P.\n\n**Note:** When a transaction reply returned from a database server is longer than 31K bytes, it is truncated to 31K and sent to the NetView Requester API. The truncation is indicated to the API requester by returning a **CNM_TRUNCATION** parameter with the EBCDIC value YES. The **CNM_TRUNCATION** parameter is the last parameter returned in a transaction reply if the truncation occurred in the reply.\n\n### Return Codes\n\nThe return codes for this command are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CNM_GOOD</td>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n<tr>\n<td>Return Code Name</td>\n<td>Value</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------------------------</td>\n<td>-------</td>\n<td>-----------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>CNM_NO_STORAGE</td>\n<td>24</td>\n<td>Storage allocation failure.</td>\n</tr>\n<tr>\n<td>CNM_DATA_TRUNC</td>\n<td>40</td>\n<td>Data is too long for gpdata buffer—truncation occurred. Actual length of the returned data is indicated in hblengh.</td>\n</tr>\n<tr>\n<td>CNM_BAD_QUEUE</td>\n<td>72</td>\n<td>Queue number specified is out of range.</td>\n</tr>\n<tr>\n<td>CNM_QUEUE_EMPTY</td>\n<td>80</td>\n<td>Specified queue is empty.</td>\n</tr>\n<tr>\n<td>CNM_BAD_LENGTH</td>\n<td>88</td>\n<td>Specified gpdatlen is not valid.</td>\n</tr>\n<tr>\n<td>CNM_BAD_NAME</td>\n<td>108</td>\n<td>Either the requested gpnameh is not valid (gpmethod=H), or the requested gpnamep did not exist in the transaction (gpmethod=P).</td>\n</tr>\n<tr>\n<td>CNM_BAD_OPTION</td>\n<td>128</td>\n<td>Invalid gpmethod is specified.</td>\n</tr>\n<tr>\n<td>CNM_BAD_ADDR</td>\n<td>160</td>\n<td>The gpdata data area address is not valid.</td>\n</tr>\n<tr>\n<td>CNM_NO_DATA</td>\n<td>268</td>\n<td>Either the specified gpnameh is valid, but no value was found (gpmethod=H), or the specified gpnamep existed in the transaction but has a value indicating a length of zero (gpmethod=P).</td>\n</tr>\n<tr>\n<td>CNM_INVALID_MESSAGE</td>\n<td>272</td>\n<td>First message on the specified queue is not a two-line message with a valid identifier, or the second line of the message is not valid.</td>\n</tr>\n<tr>\n<td>CNM_NO_MORE_DATA</td>\n<td>280</td>\n<td>No more data to be returned (gpmethod=N).</td>\n</tr>\n<tr>\n<td>CNM_BAD_CURSOR</td>\n<td>284</td>\n<td>Specified gpcursor value is out of range (gpmethod=N).</td>\n</tr>\n<tr>\n<td>CNM_BAD_TASK</td>\n<td>292</td>\n<td>Invalid task type. This service routine can be invoked only under an OST or a PPT.</td>\n</tr>\n</tbody>\n</table>\n\n**Parameter Usage Reference**\n\nTable 5 summarizes the content of fields required for using the gpmethod parameter of the CNMGETP service routine.\n\n**Table 5. Content Fields for gpmethod Parameter of CNMGETP Service Routine**\n\n<table>\n<thead>\n<tr>\n<th>Parameter Name</th>\n<th>Used when gpmethod=</th>\n<th>Input/Output</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>gpmethod</td>\n<td>P,N,H</td>\n<td>Input</td>\n<td>Decoding method to use.</td>\n</tr>\n<tr>\n<td>gpnameh</td>\n<td>H</td>\n<td>Input</td>\n<td>Name of the header parameter.</td>\n</tr>\n<tr>\n<td>gpnamep</td>\n<td>P</td>\n<td>Input</td>\n<td>Name of the requested transaction parameter.</td>\n</tr>\n<tr>\n<td></td>\n<td>N</td>\n<td>Output</td>\n<td>Name of the next transaction parameter.</td>\n</tr>\n</tbody>\n</table>\nTable 5. Content Fields for gpmethod Parameter of CNMGETP Service Routine (continued)\n\n<table>\n<thead>\n<tr>\n<th>Parameter Name</th>\n<th>Used when gpmethod =</th>\n<th>Input/Output</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>gpindex</td>\n<td>P</td>\n<td>Input</td>\n<td>Index of specified parameter.</td>\n</tr>\n<tr>\n<td></td>\n<td>N</td>\n<td>Output</td>\n<td>Index of the next parameter.</td>\n</tr>\n<tr>\n<td>gpdata</td>\n<td>P,N,H</td>\n<td>Output</td>\n<td>Area to receive requested information.</td>\n</tr>\n<tr>\n<td>gpdatlen</td>\n<td>P,N,H</td>\n<td>Input</td>\n<td>Length of the provided data area.</td>\n</tr>\n<tr>\n<td>gptype</td>\n<td>P,N</td>\n<td>Output</td>\n<td>Type of parameter value.</td>\n</tr>\n<tr>\n<td>gpqueue</td>\n<td>P,N,H</td>\n<td>Input</td>\n<td>HLL API queue number.</td>\n</tr>\n<tr>\n<td>gpcursor</td>\n<td>N</td>\n<td>Input/Output</td>\n<td>Position to scan for the next transaction parameter.</td>\n</tr>\n</tbody>\n</table>\n\nCNMSNDT and CNMGETP Debugging Support\n\nThe CNMSNDT and CNMGETP service routines support the NetView HLL API remote interactive debugger (RID) and the first failure data capture trace (FFDCT). For more information on these debugging tools, refer to “High-Level Language Services” in Tivoli NetView for OS/390 Customization: Using PL/I and C and “Diagnostic Tools for the NetView Program” in Tivoli NetView for OS/390 Diagnosis Guide.\n\nNotes:\n\n1. Both of these service routines provide input parameters and their associated values on entry and exit to the RID facility, when it is active.\n2. Both of these service routines provide the following module IDs to the NetView FFDCT:\n - 017—CNMGETP function\n - 018—CNMSNDT function\nAppendix C. Server Support API Commands and Service Routines\n\nThis appendix documents general-use programming interface and associated guidance information.\n\nThis appendix contains descriptions of the service routines associated with the NetView Bridge server support API. You can use the reference information in this section as a guide to create your own database server or transaction processor. For detailed information on creating your own database server or transaction processor, see “Chapter 3. Creating a Database Server” on page 15.\n\nThe server support API consists of HLL service routines that can be issued by transaction processors. The service routines are listed and described in detail, beginning with [CNMEGTP (CNMETRPARM) Service Routine—Get Transaction Request Parameters]. Each service routine includes an explanation of its use and syntax, as well as a complete descriptions of each field and operand.\n\nSample service routines (written in PL/I or C) are also provided in this manual. Figure 13 on page 25 shows a sample PL/I service routine. Figure 14 on page 42 shows a sample C service routine. You can use these examples as models for creating your own routines.\n\nPL/I and C Service Routines Issued from the Server Support API\n\nThis section describes the high-level language (HLL) service routines that are provided with NetView Bridge. These service routines can only be invoked by programs running outside of the NetView address space.\n\nThe server support API service routines require you to declare, initialize, and pass parameters to the API service routines according to PL/I or C programming language specifications. For more information on these specifications, refer to OS PL/I Version 2 Programming: Language Reference [Coding Your PL/I Program: Environment, Interfaces, and Restrictions] or Coding Your C Program: Interfaces and Restrictions in Tivoli NetView for OS/390 Customization: Using PL/I and C and SAA: Common Programming Interface C Reference.\n\nCNMEGTP (CNMETRPARM) Service Routine—Get Transaction Request Parameters\n\nThe CNMEGTP service routine enables you to extract the contents of a transaction request after invoking the CNMENTR routine.\n\nThe syntax for the CNMEGTP command is:\n\nPL/I CALL FORMAT:\n\nCALL CNMEGTP(bhlpbr, gpmethod, gpnameh, gpnamep, gpindex, gpdata, gpdatlen, gptype, gpcursor)\nWhere:\n\n*bhlbptr* \nIs a fullword field containing the anchor pointer used by the server support API.\n\n*gpmethod* \nIs a 1-character field that identifies the method to use for retrieving parameters from the transaction request. This field must contain one of the following values:\n\n- **H** \n Retrieve transaction header parameter and its value.\n\n- **P** \n Retrieve value of a transaction parameter by specifying the name of the transaction parameter.\n\n- **N** \n Retrieve name and value of next transaction parameter, start searching from the position pointed to by *gpcursor*.\n\n*gpnameh* \nIs an 8-character, fixed-length field used to identify the transaction header parameter that is being requested. It must be left-justified and padded with blanks. This field is required if you specify H in *gpmethod*. It is not required if you specify P or N.\n\nThe following names are valid:\n\n**TRANSID** \nSpecifies that the name of the transaction request is returned. If the returned value is CNMQUISE, it is a quiesce transaction generated by the CNMQUET service routine already invoked by the database server.\n\n**TRTYPE** \nIs a value indicating the type of transaction request that is returned. The following are the possible values:\n\n- **QERR** \n Indicates that this is a request transaction, but only error responses are to be returned to the requesting task.\n\n- **QALL** \n Indicates that this is a request transaction, but all operational and error response data is to be returned to the requesting task.\n\n- **QNON** \n Indicates that this is a request transaction, but that no responses (error condition or operational) are to be returned to the requesting task.\n\n- **CORR** \n Specifies that the correlator of the transaction request is returned. If all blanks are returned, the transaction request does not contain a correlator value.\n\n- **VOCAB** \n Specifies that the context of parameter names is returned. If all blanks are returned, the default context is used.\n\n---\n\n**PL/I MACRO FORMAT:**\n\n```\nCNMETRPARM METHOD(gpmethod) HNAME(gpnameh) PNAME(gpnamep)\nINDEX(gpindex) DATA(gpdata) LENG(gpdatlen) TYPE(gptype) CURSOR(gpcursor)\n```\nORIGNET\nSpecifies that the origin network ID of the transaction request is returned.\n\nORIGDOM\nSpecifies that the origin domain ID of the transaction request is returned.\n\nORIGTASK\nSpecifies that the origin task ID of the transaction request is returned. Normally this is the task ID of the NetView program requesting OST or PPT. However, if the received transaction request is a quiesce transaction, the *tiinq* name of this database server (as defined in CNMETIN) is returned.\n\nDESTNET\nSpecifies that the destination network ID of the transaction request is returned.\n\nDESTDOM\nSpecifies that the destination NetView domain ID of the transaction request is returned.\n\nDESTTASK\nSpecifies that the destination task ID of the transaction request is returned. The value returned should be the NetView autotask ID that serves this database server.\n\n*gpnamep*\nIs a 31-character varying-length field that has two different uses:\n\n- When you specify P with *gpmethod*, this field contains the name of the parameter whose value is being retrieved.\n- When you specify N with *gpmethod*, this field is used to receive the name of the next parameter. The search for the next parameter begins at the location pointed to by *gpcursor*.\n\nThis field is required if you specify P or N in *gpmethod*. It is not required if you specify H.\n\n*gpindex*\nContains a signed, 4-byte integer that has two different uses:\n\n- When you specify P with *gpmethod*, this field contains the index value of the array parameter whose value is being retrieved. You must specify an index value of −32,767 if the parameter is not an array parameter.\n- When you specify N with *gpmethod*, this field is used to receive the index value of the next parameter. The search for the next parameter begins at the location pointed to by *gpcursor*. A value of −32,767 is returned if this parameter is not an array type parameter.\n\nThis field is required if you specify P or N in *gpmethod*. It is not required if you specify H.\n\n*gpdata*\nIs a varying-length character field containing the value of the parameter being returned.\n\nIf the parameter type value (*gptype*) returned is GPTYPE=X'00EE', indicating that this is an EBCDIC character string, this field contains the character string in either the PL/I character varying format or the C Dsivarch format. If the\nparameter type value is GPTYPE=X'00BB', indicating that this is a binary integer, this field contains the length of the fixed binary integer variable that is used to carry the binary integer.\n\nThe first two bytes indicate the length of the fixed binary integer variable that was used to carry the integer in the transaction request. For example:\n\n- In PL/I, the length is 4 for a FIXED BIN(31,0) variable, or 2 for a FIXED BIN(15,0) variable.\n- In C, the length is 4 for a long integer variable, or 2 for a short integer variable.\n\nThe remaining 4 or 2 bytes contain the binary integer.\n\ngpdatlen\nIs a 4-byte integer that specifies the maximum length of gpdata.\n\nIf the value specified by gpdatlen is less than the length of the parameter value to be returned, the parameter value is truncated and returned in gpdata, and a return code of RET_DATA_TRUNC is generated. The full length of the parameter value that was truncated is stored in HLBLENG (Hlbleng).\n\nIf the value specified by gpdatlen is equal to or greater than the length of the parameter value to be returned, and return code RET_GOOD is issued, the length of the returned parameter value is stored in HLBLENG (Hlbleng).\n\ngptype\nIs a 2-byte, fixed-length field that indicates the type of the parameter value returned in gpdata. One of the following values is set when this procedure returns:\n\n- X'00EE'\n The returned parameter value is an EBCDIC character string.\n- X'00BB'\n The returned parameter value is an integer.\n\nThis field is required if you specify P or N in gpmethod. It is not required if you specify H.\n\ngpcursor\nIs a 4-byte integer field used to keep track of the position in the scan. When you specify N in gpmethod, it must be initialized to a binary zero before the first call to CNMEGTP. Use of this field with a nonzero value can cause unpredictable results. This field is updated each time the service routine is called.\n\nThis field is required if you specify N in gpmethod. It is not required if you specify H or P.\n\n### Return Codes\n\nThe return codes for this service routine are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RET_GOOD</td>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n<tr>\n<td>RET_END_FILE</td>\n<td>04</td>\n<td>No more parameter names or values to retrieve (GPMETHOD=N).</td>\n</tr>\n<tr>\n<td>RET_BAD_LENGTH</td>\n<td>16</td>\n<td>The gpdatlen specified contains an invalid value.</td>\n</tr>\n<tr>\n<td>Return Code Name</td>\n<td>Value</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------------------</td>\n<td>-------</td>\n<td>-------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>RET_BAD_NAME</td>\n<td>32</td>\n<td>The requested <em>gpnameh</em> was invalid (GPMETHOD=H), or the requested <em>gpnamep</em> did not exist in the transaction (GPMETHOD=P).</td>\n</tr>\n<tr>\n<td>RET_NO_DATA</td>\n<td>40</td>\n<td>The specified <em>gpnameh</em> is valid, but either no value was found (GPMETHOD=H), or the specified <em>gpnamep</em> contains a length value of zero (GPMETHOD=P).</td>\n</tr>\n<tr>\n<td>RET_PROCESSING_ERROR</td>\n<td>48</td>\n<td>Processing error during decoding.</td>\n</tr>\n<tr>\n<td>RET_BAD_CURSOR</td>\n<td>76</td>\n<td>Specified cursor value is not valid (GPMETHOD=N).</td>\n</tr>\n<tr>\n<td>RET_BAD_METHOD</td>\n<td>80</td>\n<td>The specified <em>gpmethod</em> is not valid.</td>\n</tr>\n<tr>\n<td>RET_DATA_TRUNC</td>\n<td>88</td>\n<td>The parameter name or value is too long for the <em>gpdata</em> field provided for the returned data. Truncation has occurred. The actual length of the returned data is contained in HLBLENG.</td>\n</tr>\n</tbody>\n</table>\n\n**Parameter Usage Reference**\n\nTable 6 summarizes the content of fields required for using the *gpmethod* parameter of the CNMEGTP service routine.\n\nTable 6. Content Fields for *gpmethod* Parameter of CNMEGTP Service Routine\n\n<table>\n<thead>\n<tr>\n<th>Parameter Name</th>\n<th>Used when <em>gpmethod</em>=</th>\n<th>Input/Output</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><em>gpmethod</em></td>\n<td>P,N,H</td>\n<td>Input</td>\n<td>Decoding method to use.</td>\n</tr>\n<tr>\n<td><em>gpnameh</em></td>\n<td>H</td>\n<td>Input</td>\n<td>Name of the header parameter.</td>\n</tr>\n<tr>\n<td><em>gpnamep</em></td>\n<td>P</td>\n<td>Input</td>\n<td>Name of the requested transaction parameter.</td>\n</tr>\n<tr>\n<td><em>gpnamep</em></td>\n<td>N</td>\n<td>Output</td>\n<td>Name of the next transaction parameter.</td>\n</tr>\n<tr>\n<td><em>gpindex</em></td>\n<td>P</td>\n<td>Input</td>\n<td>Index of specified parameter.</td>\n</tr>\n<tr>\n<td><em>gpdata</em></td>\n<td>P,N,H</td>\n<td>Output</td>\n<td>Area to receive requested information.</td>\n</tr>\n<tr>\n<td><em>gpdatalen</em></td>\n<td>P,N,H</td>\n<td>Input</td>\n<td>Length of the provided data area.</td>\n</tr>\n<tr>\n<td><em>gptype</em></td>\n<td>P,N</td>\n<td>Output</td>\n<td>Type of parameter value.</td>\n</tr>\n<tr>\n<td><em>gpcursor</em></td>\n<td>N</td>\n<td>Input/Output</td>\n<td>Position to scan for the next transaction parameter.</td>\n</tr>\n</tbody>\n</table>\nCNMENTR (CNMETNEXT) Service Routine—Get Next Transaction Request\n\nThe CNMENTR service routine receives the next transaction from the tiing queue. After the transaction request is received, the parameters can be examined with calls to CNMEGTP.\n\nThe syntax for the CNMENTR command is:\n\n**PL/I CALL FORMAT:**\n\nCALL CNMENTR(bhlbptr)\n\n**PL/I MACRO FORMAT:**\n\nCNMETNEXT\n\n**C INVOCATION:**\n\nvoid Cnmentr()\n\n*Where:*\n\n*bhlbptr*\n\nIs a fullword field containing the anchor pointer used by the server support API.\n\n**Return Codes**\n\nThe return codes for this service routine are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RET_GOOD</td>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n<tr>\n<td>RET_NOT_FOUND</td>\n<td>20</td>\n<td>No transaction request available in queue tiing.</td>\n</tr>\n<tr>\n<td>RET_STORAGE_FAILURE</td>\n<td>52</td>\n<td>Could not obtain working storage.</td>\n</tr>\n<tr>\n<td>RET_PPI_FAILURE</td>\n<td>1000 +n</td>\n<td>When the routine invoked the program-to-program interface (PPI) module, it received PPI failure return code n.</td>\n</tr>\n</tbody>\n</table>\n\nCNMERTR (CNMETREADY) Service Routine—Ready For Next Transaction Request\n\nThe CNMERTR service routine sends a READY token to the NetView autotask that serves this database server. This token indicates that the server is ready to process another transaction request.\n\nThe syntax for the CNMERTR command is:\n\n**PL/I CALL FORMAT:**\n\nCALL CNMERTR(bhlbptr)\nWhere:\n\n*bhlbptr*\n\nIs a fullword field containing the anchor pointer used by the server support API.\n\n### Return Codes\n\nThe return codes for this service routine are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RET_GOOD</td>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n<tr>\n<td>RET_BAD_STATE</td>\n<td>24</td>\n<td>Quiesce transaction already issued.</td>\n</tr>\n<tr>\n<td>RET_PROCESSING_ERROR</td>\n<td>48</td>\n<td>Processing error occurred while encoding the READY token.</td>\n</tr>\n<tr>\n<td>RET_STORAGE_FAILURE</td>\n<td>52</td>\n<td>Could not obtain working storage.</td>\n</tr>\n<tr>\n<td>RET_PPI_FAILURE</td>\n<td>1000 +n</td>\n<td>When the routine invoked the PPI module, it received PPI failure return code n.</td>\n</tr>\n</tbody>\n</table>\n\n### CNMESTR (CNMSENDSTR)—Send Transaction Reply to NetView Requester\n\nThe CNMESTR service routine sends a transaction reply to the requester in response to a transaction request.\n\nThe syntax for the CNMESTR command is:\n\n**PL/I CALL FORMAT:**\n\n```pli\nCALL CNMESTR(bhlbptr,transid,trtype,destnet,destdom,desttask,\norignet,origdom,origtask,vocab,corr,respcode,parms)\n```\n\n**PL/I MACRO FORMAT:**\n\n```pli\nCNMSENDSTR TRANSID(transid) TRTYPE(trtype) DESTNET(destnet)\nDESTDOM(destdom) DESTTASK(desttask) ORIGNET(orignet) ORIGDOM(origdom)\nORIGTASK(origtask) VOCAB(vocab) CORR(corr) RESPCODE(respcode)\nPARMS(parms)\n```\nC INVOCATION:\n\n```c\nvoid Cnmestr(char *transid, char *trtype, char *destnet, char *destdom, char *desttask, char *orignet, char *origdom, char *origtask, char *vocab, char *corr, char *respcode, Dsicprm **parms)\n```\n\n**Where:**\n\n- `bhlbptr` \n Is a fullword field containing the anchor pointer used by the server support API.\n\n- `transid` \n Is the 8-character name of the transaction being executed. If the value of this field is less than 8 characters, it must be left-justified and padded with blanks. No embedded blanks are allowed in this value. The value of this field is obtained from the TRANSID field of the CNMEGTP service routine.\n\n- `trtype` \n Is a 4-character parameter that indicates the transaction processing that was performed. The only valid value for this field is RPLY, which indicates that this is a reply in response to a request.\n\n- `destnet` \n Is a fixed-length 8-character field that identifies the network that originated the transaction request. If the value of this field is less than 8 characters, it must be left-justified and padded with blanks. No embedded blanks are allowed in this value. The value for this field is obtained from the ORIGNET field of service routine CNMEGTP.\n\n- `destdom` \n Is a fixed length 8-character field that identifies the domain that originated the transaction request. If the value of this field is less than 8 characters, it must be left-justified and padded with blanks. No embedded blanks are allowed in this value. The value for this field is obtained from the ORIGDOM field of service routine CNMEGTP.\n\n- `desttask` \n Is a fixed-length 8-character field that identifies the task ID of the NetView OST or PPT that originated this transaction request. If the value of this field is less than 8 characters, it must be left-justified and padded with blanks. No imbedded blanks are allowed in this value. The value for this field is obtained from the ORIGTASK field of service routine CNMEGTP.\n\n- `orignet` \n Is a fixed-length 8-character field that identifies the network ID of the network that is processing this transaction. If the value of this field is less than 8 characters, it must be left-justified and padded with blanks. No embedded blanks are allowed in this value. The value for this field is obtained from the DESTNET field of service routine CNMEGTP.\n\n- `origdom` \n Is a fixed-length 8-character field that identifies the originating domain ID of the domain that is processing this transaction. If the value of this field is less than 8 characters, it must be left-justified and padded with blanks. No embedded blanks are allowed in this value. The value for this field is obtained from the DESTDOM field of service routine CNMEGTP.\n\n- `origtask` \n Is a fixed-length 8-character field that identifies the task ID of the autotask that serves this database server. If the value of this field is less than 8 characters, it\nmust be left-justified, and padded with blanks. No embedded blanks are allowed in this value. The value for this field is obtained from the DESTTASK field of service routine CNMEGTP.\n\nvocab\nIs a fixed-length 8-character field that identifies the context that is used to interpret the parameter names in the transaction request. The value of this field is obtained from the VOCAB field of service routine CNMEGTP.\n\ncorr\nIs a fixed length 8-character field that associates a response with any data that was kept by the requester at the time the transaction was issued. The value of this field is obtained from the CORR field of service routine CNMEGTP.\n\nrespcode\nIs an 8-character fixed-length field that is used to summarize the results of a transaction request that has been processed. If no response code is required, the value of this field should be set to blanks.\n\nparms\nContains a pointer to a linked list of parameter blocks. If no parameters are to be sent with the reply, this field should be set to either a C null (X'00000000') or a PL/I null (X'FF000000'). The following is the structure of a parameter block:\n\nprmlink\nContains a pointer to the next parameter block in the chain. If this is the last parameter in the chain, this field should be set to either a C null (X'00000000') or a PL/I null (X'FF000000').\n\nprmnaml\nContains a halfword binary integer that defines the length of the prmname field. This value must be in the range 1—31.\n\nprmname\nIs a fixed-length 31-character field that contains the name of the parameter.\n\nprmindex\nContains a signed halfword binary integer that identifies the index value within a parameter that happens to be an array. A value of minus 32,767 is interpreted to mean that this parameter is not an array. Parameter arrays are intended to handle multiple values for a given parameter (for example, lines of text in a problem description).\n\nprmtype\nContains a halfword binary integer that identifies the type of parameter. There are two possible values for this field:\n\nX'00EE'\nIndicates that the parameter value is an EBCDIC character string.\n\nX'00BB'\nIndicates that the parameter value is a binary integer.\n\nprmleng\nContains a halfword binary integer that identifies the length of the parameter value. The value of this field must be less than 31,000.\n\nIf the parameter type value (prmtype) returned is PRMTYPE=X'00EE', indicating that this is an EBCDIC character string, this field contains the length of the character string in the number of bytes. If the parameter\ntype value is PRMTYPE=X'00BB', indicating that this is a binary integer, this field contains the length of the fixed binary integer variable that is used to carry the binary integer. For example:\n\n- In PL/I, the length is 4 for a FIXED BIN(31,0) variable, or 2 for a FIXED BIN(15,0) variable.\n- In C, the length is 4 for a long integer variable, or 2 for a short integer variable.\n\n**Note:** The actual maximum length of any parameter value depends on the length of all fields in the transaction. The maximum length of any transaction is 31K. For important information on calculating the size of a transaction, see \"Understanding Transaction Size Limitations\" on page 55.\n\nIf a transaction reply is longer than the maximum length, it is truncated and sent. A CNM_TRUNCATION parameter with the EBCDIC value YES is placed at the end of the reply to indicate the truncation to the NetView Requester API receiver.\n\n**prmptr** Contains a pointer to the value of the parameter. If you do not specify a value, this field should be set to either a C null (X'00000000') or a PL/I null (X'FF000000').\n\n**Note:** The NetView program provides the mapping of the parameter block in PL/I and C under the include file names DSIPPRM (for PL/I), and DSICPRM (for C). These files are included by DSIBPLI and DSIBC. Therefore, all you need to do is include DSIBPLI or DSIBC into your program.\n\n### Return Codes\n\nThe return codes for this service routine are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RET_GOOD</td>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n<tr>\n<td>RET_BAD_TRAN_HDR</td>\n<td>36</td>\n<td>One of the transaction header parameters (for example, transid, trtype, destnet, destdom, desttask, orignet, origdom, or origtask) contains an invalid value.</td>\n</tr>\n<tr>\n<td>RET_PROCESSING_ERROR</td>\n<td>48</td>\n<td>Processing error occurred while encoding the transaction reply.</td>\n</tr>\n<tr>\n<td>RET_STORAGE_FAILURE</td>\n<td>52</td>\n<td>Could not obtain working storage.</td>\n</tr>\n<tr>\n<td>RET_TRAN_REPLY_TRUNC</td>\n<td>60</td>\n<td>Transaction reply was truncated and sent.</td>\n</tr>\n<tr>\n<td>RET_PPI_FAILURE</td>\n<td>1000 +n</td>\n<td>When the routine invoked PPI module it received PPI failure return code n.</td>\n</tr>\n<tr>\n<td>RET_BAD_TRAN_PARM</td>\n<td>10000 +n</td>\n<td>The rth parameter block in the link list pointed to by the PARMS contains either an invalid parmnaml or prmleng value, or both.</td>\n</tr>\n</tbody>\n</table>\nCNMETIN (CNMETINIT) Service Routine—Initialize the Server Support API\n\nThe CNMETIN service routine is called once to initialize the database server.\n\nThe syntax for the CNMETIN command is:\n\n**PL/I CALL FORMAT:**\n\nCALL CNMETIN(bhlbprr,tiinq,tiinqlim,tioutq)\n\n**PL/I MACRO FORMAT:**\n\nCNMETINIT INQUEUE(tiinq) INQUEUELIM(tiinqlim) OUTQUEUE(tioutq)\n\n**C INVOCATION:**\n\nvoid Cnmetin(char *tiinq,int tiinqlim,char *tioutq)\n\n**Where:**\n\n*bhlbprr*\n\nIs a fullword field that contains the anchor pointer on return from CNMETIN. The anchor pointer is required as an input parameter by all other service routines.\n\n*tiinq*\n\nIs an 8-character fixed-length field containing the name of the program-to-program interface (PPI) queue that is used to receive transaction requests from the NetView program. This field must contain 1-8 characters. These characters can be uppercase alphabetic (A—Z), numeric (0—9), or $, %, &, @, and #. If this field does not contain 8 characters, it must be left-justified and padded with blanks.\n\n*tiinqulim*\n\nIs a 4-byte integer field containing the limit of the PPI *tiinq* queue. This limit cannot be a negative value. The recommended value for this field is the number of ready tokens that are issued by this database server, multiplied by four.\n\n*tioutq*\n\nIs an 8-character fixed-length field containing the name of the PPI queue to which transaction replies are sent.\n\n**Note:** This is the same name that you assigned to the *queue* parameter of the RTRINIT command (see RTRINIT Command on page 87).\n\nThis field must contain 1-8 characters. These characters can be uppercase alphabetic (A—Z), numeric (0—9), or $, %, &, @, and #. If this field does not contain 8 characters, it must be left-justified and padded with blanks.\n\n**Return Codes**\n\nThe return codes for this service routine are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RET_GOOD</td>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n<tr>\n<td>RET_BAD_TIINQLIM</td>\n<td>28</td>\n<td>Specified <em>tiinqlim</em> contains a negative value.</td>\n</tr>\n</tbody>\n</table>\n## CNMETQU (CNMETQUIESCE) Service Routine—Quiesce This Database Server\n\nThe CNMETQU service routine is called to initiate an orderly shutdown of the database server issuing the call. Other database servers remain active. After CNMETQU is called, no further calls to CNMERTR (ready for next transaction request) are accepted.\n\nThe database server continues processing until the quiesce transaction is returned from the NetView Bridge dispatcher. At that time, the database server calls CNMETRM (terminate the server support API).\n\nThe quiesce transaction that the NetView program receives from this service routine can be identified by checking the TRANSID field (it must contain a value of CNMQUISE). In addition, the ORIGTASK field contains the database server’s tiing name (as defined in service routine CNMETIN).\n\nThe syntax for the CNMETQU command is:\n\n**PL/I CALL FORMAT:**\n\n```pli\ncall cnmetqu(bhlbptr)\n```\n\n**PL/I MACRO FORMAT:**\n\n```pli\ncnmetquiesce\n```\n\n**C INVOCATION:**\n\n```c\nvoid cnmetqu()\n```\n\n**Where:**\n\n`bhlbptr` \nIs a fullword field containing the anchor pointer used by the server support API.\n\n### Return Codes\n\nThe return codes for this service routine are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RET_GOOD</td>\n<td>0</td>\n<td>Successful.</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RET_STORAGE_FAILURE</td>\n<td>52</td>\n<td>Could not obtain storage for the required buffers that would be used by the server support API. Initialization failed.</td>\n</tr>\n<tr>\n<td>RET_LOAD_FAILURE</td>\n<td>84</td>\n<td>The initialization routine was unable to load PPI module CNMNETV. Initialization failed.</td>\n</tr>\n<tr>\n<td>RET_PPI_FAILURE</td>\n<td>1000 +n</td>\n<td>When the routine invoked PPI module, it received PPI failure return code n. Initialization failed.</td>\n</tr>\n</tbody>\n</table>\n## CNMETRM (CNMETTERM) Service Routine—Terminate the Server Support API\n\nThe CNMETRM service routine allows you to disconnect the database server from the NetView program and clean up the API control blocks. No further API calls can be issued after this service routine is called, unless you reinitialize the server by calling CNMETIN.\n\nThe syntax for the CNMETRM command is:\n\n**PL/I CALL FORMAT:**\n\nCALL CNMETRM(bhlbpwr)\n\n**PL/I MACRO:**\n\nCNMETTERM\n\n**C INVOCATION:**\n\nvoid Cnmetrm()\n\n**Where:**\n\n*bhlbpwr*\n\nIs a fullword field containing the anchor pointer used by the server support API.\n\n## CNMEWAT (CNMETWAIT) Service Routine—Wait for a Transaction Request\n\nThe CNMEWAT service routine is called to wait for work from either the input queue (from the NetView program) or from some other source (the posting of an event control block).\n\nThe syntax for the CNMEWAT command is:\n\n**PL/I CALL FORMAT:**\n\nCALL CNMEWAT(bhlbpwt,waecbp)\nPL/I MACRO FORMAT:\nCNMETWAIT ECBLIST(waecbp)\n\nC INVOCATION:\n\nvoid Cnmewat(void *waecbp)\n\nWhere:\n\nbhlbp\n\nIs a fullword field containing the anchor pointer used by the server support API.\n\nwaecbp\n\nContains the pointer to a list of event control blocks (ECBs) that should be included in the list for which CNMEWAT is waiting. The ECB for work waiting from the tiinq queue (from the NetView program) is provided by the service routine, and is not included in this ECB list.\n\nAn example of an ECB that should be included is the termination ECB. This ECB allows the server to terminate the wait state should some other event (such as an MVS STOP command) occur before a transaction is received.\n\nIf no ECBs are to be included in the wait list, this field should be set to a C or PL/I null value. If specified, the ECB list contains a contiguous list of fullword addresses of the appropriate ECBs. The last entry in the list of ECB addresses has its high-order bit (0) set to 1 to indicate the end of the list.\n\nReturn Codes\n\nThe return codes for this service routine are:\n\n<table>\n<thead>\n<tr>\n<th>Return Code Name</th>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RET_WAIT_POSTED_PPI</td>\n<td>8</td>\n<td>PPI tiinq ECB is posted. One or more transaction requests are available. If you have specified your own ECB list in WAECBP, check to see if the ECBs in the list have also been posted.</td>\n</tr>\n<tr>\n<td>RET_WAIT_POSTED</td>\n<td>12</td>\n<td>One or more user-provided ECBs have been posted. The PPI tiinq ECB is not posted and no transaction request is available.</td>\n</tr>\n<tr>\n<td>RET_STORAGE_FAILURE</td>\n<td>52</td>\n<td>Could not obtain working storage.</td>\n</tr>\n</tbody>\n</table>\n\nServer Support API Debugging Support\n\nThe server support API service routines maintain an 8-entry continuously wrapping trace area. The name of this in-storage trace area is HLBFFOCA. It is located in control block DSIBHLB. You can print the contents of the trace area during execution by including appropriate print instructions in your PL/I or C program.\nTrace entries are recorded at entry to and exit from all service routines. In the event of an abnormal end (abend), this area indicates which server support API module was running and either the address of the calling routine or the return code from the service routine.\n\nEach entry in the trace area is 6 bytes in length, making the total size of the trace area 48 bytes. Each trace point is identified by a unique 16-bit ID number. The first 12 bits represent the module ID and the next 4 bits represent the location ID within the module.\n\nThe following are the hexadecimal values and corresponding modules for the module IDs:\n\n<table>\n<thead>\n<tr>\n<th>Hex Value</th>\n<th>Module</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>X'051'</td>\n<td>CNMETIN</td>\n</tr>\n<tr>\n<td>X'052'</td>\n<td>CNMETRM</td>\n</tr>\n<tr>\n<td>X'053'</td>\n<td>CNMEWAT</td>\n</tr>\n<tr>\n<td>X'054'</td>\n<td>CNMEGTP</td>\n</tr>\n<tr>\n<td>X'055'</td>\n<td>CNMENTR</td>\n</tr>\n<tr>\n<td>X'056'</td>\n<td>CNMETQU</td>\n</tr>\n<tr>\n<td>X'057'</td>\n<td>CNMERTR</td>\n</tr>\n<tr>\n<td>X'058'</td>\n<td>CNMESTR</td>\n</tr>\n</tbody>\n</table>\n\nThe following are the hexadecimal values and corresponding debug points for the location IDs:\n\n<table>\n<thead>\n<tr>\n<th>Hex Value</th>\n<th>Debug Point</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>X'0'</td>\n<td>Module entry</td>\n</tr>\n<tr>\n<td>X'F'</td>\n<td>Module exit</td>\n</tr>\n</tbody>\n</table>\n\nThe next 4 bytes of the trace entry contain debugging information captured at the debugging point. If the error occurred upon entry, these 4 bytes contain the address of the caller (from register 14 of the caller). If the error occurred during exit, these 4 bytes contain the return code from the service routine.\nAppendix D. NetView Bridge Messages and Abend Codes\n\nThis appendix lists the messages and abend codes that are used with the NetView Bridge function.\n\nMessages for the NetView Bridge\n\nThe NetView Bridge uses several messages during normal processing. Some messages are passed across the bridge with data attached to them and are used primarily for constructing transaction requests and replies. Use the NetView program’s online help for additional information on the NetView Bridge messages.\n\nThe NetView Bridge messages are:\n- DWO150I\n- DWO151I\n- DWO152I\n- DWO156I\n- DWO157I\n- DWO530I\n- DWO531I\n- DWO533I\n- DWO534I\n- DWO535I\n- DWO536I\n- DWO537I\n- DWO539I\n- DWO546I\n- DWO548I\n- DWO550I\n- DWO568I\n- DWO569I\n\nAbend Codes for the NetView Bridge\n\nAn abend code is generated for an unrecoverable error. This completion code is issued when an internal NetView logic error occurs or when the NetView program detects a serious problem. The code is presented on an abend dump listing as user code Uxx, where xx is the decimal code as described in this section.\n\nTable 7. Abend Codes for NetView Bridge\n\n<table>\n<thead>\n<tr>\n<th>Decimal Abend Code</th>\n<th>Hex Abend Code</th>\n<th>Explanation of the Abend</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>85</td>\n<td>X’55’</td>\n<td>The initialization routine could not obtain storage for the primary anchor control block whose address would be returned in the bhlbprr parameter of CNMETIN (CNMETINIT). Initialization of the server support API failed.</td>\n</tr>\n<tr>\n<td>86</td>\n<td>X’56’</td>\n<td>The initialization routine could not load either of the required NetView load modules DSIEHLAR, DSIEHL24, or both. Initialization of the server support API failed.</td>\n</tr>\n<tr>\n<td>91</td>\n<td>X’05B’</td>\n<td>Should not occur; severe error returns from the NetView Bridge dispatcher or remote dispatcher.</td>\n</tr>\n</tbody>\n</table>\nA task that has abended the maximum number of times (MAXABEND) no longer processes transactions. Refer to “Documenting and Reporting Problems” in *Tivoli NetView for OS/390 Diagnosis Guide* for recovery procedures.\nIndex\n\nSpecial Characters\n&WAIT 56, 57\n\nA\nabend codes 123\nactivity checklist 7\nadding an operator ID 11\nadding operator ID 8\nadjusting NetView Bridge 83\nadjusting queue limits 84\nAPAR 85, 86\nassigning queue names 10\nautomating startup\n for a database server 80\n for NetView Bridge 80\n for NetView Bridge remote access 80\n\nB\nbridge dispatcher 5, 8\n\nC\nC command procedure\n example 70\n initializing parameters 65\n processing replies 65\n receiving replies 65\n sending transaction requests 65\nCNMCMRD service routine 65\nCNMCSSIR router task 80\nCNMGETP service routine 107, 111\nCNMENTR service routine 112\nCNMERT service routine 112\nCNMESTR service routine 113\nCNMETIN service routine 117, 123\nCNMETINIT service routine 117, 123\nCNMETNEXT service routine 112\nCNMETQU service routine 118\nCNMETQUESCE service routine 118\nCNMETREADY service routine 112\nCNMETRM service routine 119\nCNMETERM service routine 119\nCNMETWAIT service routine 119\nCNMEWAT service routine 119\nCNMGETP service routine\n debugging support 105\n example command processor using C 70\n example command processor using PL/I 66\n sending transactions 65\n usage 100\nCNMGETPARM service routine\n example command processor using C 70\n example command processor using PL/I 66\n usage 100\nCNMSENDSTR service routine 113\nCNMSENDTR service routine 70, 96\nCNMSNDT service routine\n debugging support 105\n example command processor using C 70\n example command processor using PL/I 66\n sending transactions 65\n usage 96\ncoding a database server for the server support API\n using C 16\ncoding database server, server support API\n using PL/I 15\ncollecting problem information 85\ncompiling a database server with server support API\n using PL/I 22\ncompiling database server, server support API\n using C 23\ncomponents of NetView Bridge 3, 4\ncontrol blocks\n for C 16\n for PL/I 16\ncontrolling flow 18\ncreating a transaction processor 10\ncreating command procedures\n NetView Bridge 10\n NetView command list language and REXX 56\n PL/I and C 64\n remote NetView Bridge 12\ncreating database server 15, 17\ncreating transaction processor 20\n\nD\ndatabase server 20, 79\ndisplaying support\n CNMSNDT and CNMGETP 105\n server support API service routines 120\nDEFAULTS command 91, 96\ndesigning transaction processors 20\ndesirable and undesirable traffic 83\nDISBQL command 84\ndocumenting a database server 15\nDSIBHLB control block 120\nDSICMD member 9, 11, 12\nDSINBR62 command 12\nDSINBRLG command 12\nDSINBRSL command 9, 12\nDSINBTCM command 9, 12\nDSIOF member 8, 11\nDSIPARM data set\n DSICMD member 9, 12\n DSIOF member 8, 11\nDSIPRF data set 8, 11\n\nE\nevent control block 51\nevent control block 51\nexample assembly language source code 51\nexample command processor\n in C 70\n in NetView command list language 61\n in PL/I 66\n in REXX 57\nexample program using the server support API\n using C 41\n using PL/I 24\n\nF\nforwarding transaction replies 22\n\nH\nheader information 55\nHLL command procedures 64, 66\nHLL service routines\n requestor API 91, 96\n server support API 107\nhow NetView Bridge remote access works 3\nhow NetView Bridge works 1\n\nI\ninitializing database server 17\ninstalling NetView Bridge 7\ninteracting with the database interface 21\ninvoking transaction processors 19\n\nJ\njob control language (JCL) 22, 23\n\nL\nlimiting traffic, bridge 83\nlink editing a database server with server support API\n using C 23\nlink editing database server, HLL command procedures 66\nlink editing database server, server support API\n using PL/I 22\nlinking parameter blocks 21\n\nM\nmessages 123\nMSGREAD command 57\nMVS STOP command 120\n\nNetView Bridge (continued)\ncomponents (continued)\n transaction processors 6\n user-written command procedures 5\ndebugging support\n CNMSNDT and CNMGETP 105\n for server support API service routines 120\noverview 1\nstart up 79\nNetView Bridge remote access\ncomponents\n remote dispatcher 6\n user-written command procedures 5\noverview 1\nstart up 79\nNetView Bridge Requester API 5, 91\nNetView command list language command procedures\nexample 61\n initializing parameters 56\n processing replies 57\n receiving replies 56\n sending transaction requests 57\nNetView server support API 5\nNetView subsystem address space 6, 79\n\nO\nobtaining transaction identifiers 19\nopening APAR, Tivoli 86\noperator station task (OST) 56, 64\noptimizing performance 83\n\nP\npackaging code 55\nparameter size 55\nparameter usage reference, CNMEGTP 111\nparameter usage reference, CNMGETP 104\nparameters passed, server support API 15\nperformance considerations 83\nPL/I and C Service Routines\n for NetView Bridge Requester API\n CNMGETP 100\n CNMGETPARG 100\n CNMSENDTR 96\n CNMSNDT 96\ndebugging support 105\ndescription 91\n for Server Support API\n CNMGETP 107\n CNMENTR 112\n CNMERTR 112\n CNMESTR 113\n CNMETIN 117\n CNMETINIT 117\n CNMETNEXT 112\n CNMETQU 118\n CNMETQUIESCE 118\n CNMTRGET 112\n CNMTRRM 119\n CNMTRPARG 107\n CNMETTERM 119\nPL/I and C Service Routines (continued)\n CNMETWAIT 119\n CNMEWAT 119\n CNMSENDSTR 113\n debugging support 120\n description 107\nPL/I command procedure\n example 66\n initializing parameters 65\n processing replies 65\n receiving replies 65\n sending transaction requests 65\nPPI 79, 87\nprimary program operator interface task (PPT) 56, 91\nprocessing transaction requests 20\nproduct overview 1\nPTFs 85, 86\n\nQ\nqueues\n description 4, 5\n displaying 84\n naming, RTRINIT command 87\n\nR\nreceiving transactions 18\nremote dispatcher 6\nREMOTEBR command 11, 12, 89\nreporting problem 85\nreturn codes\n C 17\n CNMEGTP (CNMETRPARM) 110\n CNMENTR (CNMETNEXT) 112\n CNMERTR (CNMETREADY) 113\n CNMESTR (CNMSENDSTR) 116\n CNMETIN (CNMETINIT) 117\n CNMETOU (CNMETQUIESCE) 118\n CNMGETP (CNMGETPRAM) 103\n CNMSNDT (CNMSENDTR) 99\n CNMWAT (CNMETWAIT) 120\nPL/I 16\n REMOTEBR 90\n RTRINIT 89\n TRANRCV 95\n TRANSND 94\nREXX command procedures\n example 57\n initializing parameters 56\n processing replies 57\n receiving replies 56\n sending transaction requests 57\nRID 85, 105\nRTRINIT command 87\n adjusting queue limits 84\n creating a NetView Bridge dispatcher profile 8\n description 87\n usage 9, 12\nRTRQUEUE command 9, 12\nrun-time options (continued)\n PL/I 15\n\nS\nselecting NetView 8\nsending ready tokens 18\nsetting up NetView Bridge 7, 8\nsetting up NetView Bridge remote access 7, 11\nsoftware requirements 8\nsoftware support database 86\nspeed, processing 83\nstarting up\n a database server 79\n NetView Bridge 79\n NetView Bridge remote access 79\n\nT\nTivoli Customer Support 86\nTRANRCV command\n command model statements 9, 12\n description 94\ntransaction parameter blocks 21\ntransaction processors 6\ntransaction size 55, 56\nTRANSND command\n command model statements 9, 12\n description 91\nTRAP command 56, 65\n\nU\nuser data 55\nusing multiple database servers 10, 83\n\nW\nwaiting, transactions 19\nwriting command procedures 56, 64"}}},{"rowIdx":87,"cells":{"id":{"kind":"string","value":"e82dd509154c3200add8d3c73b68f7c4bc34ac36"},"text":{"kind":"string","value":"CASE STUDY I\n\nFINAL REPORT DEVELOPED FOR LARGE SCALE SOFTWARE SYSTEM DESIGN OF THE AN/TYC-39 STORE AND FORWARD MESSAGE SWITCH USING THE ADA PROGRAMMING LANGUAGE\n\nU. S. ARMY CECOM CONTRACT NO. DAAK80-81-C-0108\n\nVOLUME III OF IV\n\nGENERAL DYNAMICS DATA SYSTEMS DIVISION CENTRAL CENTER P. O. BOX 748 FORT WORTH, TX 76101\n\nDISTRIBUTION STATEMENT A\nApproved for public release\n\n83 01 12 031\nAda Capability Study: Design of the Message Switching System\nAN/TYC-39 Using the Ada Programming Language\n\n4. Title and Subtitle\n\nAn Ada oriented framework for the design and documentation of the U. S. Army TYC-39 store and forward message switch (military software) system is presented. This document package contains a Requirements, Design, Ada Integrated Methodology, and Final Report section. A methodology to use Ada in specifying requirements, design, and the implementation of a system was developed. This methodology was used to redesign the TYC-39 message switch system. A selected software module was programmed after the redesign.\nCASE STUDY I\n\nFINAL REPORT DEVELOPED FOR\nLARGE SCALE SOFTWARE SYSTEM DESIGN\nOF THE\nAN/TYC-39 STORE AND FORWARD\nMESSAGE SWITCH\nUSING\nTHE ADA PROGRAMMING LANGUAGE\n\nU. S. ARMY CECOM\nCONTRACT NO. DAAK80-81-C-0108\n\nVOLUME III OF IV\n\nGENERAL DYNAMICS\nDATA SYSTEMS DIVISION\nCENTRAL CENTER\nP. O. BOX 748\nFORT WORTH, TX 76101\nSCOPE\n\nThe system requirements herein described are a subset of the U.S. Army TYC-39 store and forward message switch. In order to understand the terminology used in this document, Chapters 1 and 2 of the Ada Integrated Methodology (developed by General Dynamics under the same contract) must be thoroughly reviewed.\n\nThe purpose of this document is to describe an Ada oriented framework for the design and documentation of an existing large scale military software system. It is not a B5 or C5 specification, although it is anticipated that the Functional Decompositional Models and Concurrency Diagrams will form a basis for a B5, while the Ada Functional Requirements should serve as a basis for C5 equivalent specifications. Hardware and software have been specified functionally in Ada form. Thus, the optimum hardware/software partitioning and hardware description is to be a part of the design process (next phase).\n\nDue to the complexity of the switch, certain considerations were assumed as follows:\n\n1. Modems, cryptographic, and line multiplexor equipment are external to the switch.\n2. The data adapter equipment is not supported.\n3. Although discussed, the operator interface is not described here. A user interactive conversational approach is recommended, but not considered a truly real time aspect of the system.\n4. Y-community traffic is considered only to the extent discussed in the non-classified documents used in the project.\n5. Although journal and reference storage tapes are generated, the OFF LINE functions, such as message search, are not considered.\n6. Mode III, VI, and higher line protocols are not included.\nThe following documents, in addition to the Ada Integrated Methodology developed by General Dynamics, were used in developing this specification:\n\n1. Performance specification, central office, communications, automatic, TT-B1-1101-0001A.\n3. Communication Instructions, Tape Relay-Procedures, ACP 127(D).\n**TABLE OF CONTENTS**\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. System Overview</td>\n<td>1</td>\n</tr>\n<tr>\n<td>1.1 Message Switch System Description</td>\n<td>2</td>\n</tr>\n<tr>\n<td>1.2 Message Switch System Diagram, Node A0-1</td>\n<td>3</td>\n</tr>\n<tr>\n<td>1.3 Top Level Data Flow Diagram (DFD), Node A0</td>\n<td>6</td>\n</tr>\n<tr>\n<td>2. Functional Decomposition Models and</td>\n<td>7</td>\n</tr>\n<tr>\n<td>Ada Functional Requirements</td>\n<td></td>\n</tr>\n<tr>\n<td>2.1 Startup/Recovery</td>\n<td>8</td>\n</tr>\n<tr>\n<td>2.2 Assemble Messages</td>\n<td>22</td>\n</tr>\n<tr>\n<td>2.3 Process Messages</td>\n<td>97</td>\n</tr>\n<tr>\n<td>2.4 Transmit Messages</td>\n<td>124</td>\n</tr>\n<tr>\n<td>3. Data Dictionary and Logical Data Structures</td>\n<td>162</td>\n</tr>\n<tr>\n<td>4. Non-functional Requirements</td>\n<td>183</td>\n</tr>\n<tr>\n<td>5. Concurrency Diagram</td>\n<td>187</td>\n</tr>\n</tbody>\n</table>\n(This page intentionally left blank.)\nSystem Overview\nMESSAGE SWITCH SYSTEM DESCRIPTION\n\nThe purpose of the TYC-39 message switch is to act as an automatic relay for digital message data in a battlefield functional area (BFA). The equipment is van mounted, which allows the mobility required by ground forces. Although the messages originate at a keyboard terminal, the switch is capable of interfacing to nearly all digital communications equipment in the inventory of the U.S. Army and allied armed forces.\n\nThe simplified message switch environment considered in this project is depicted in the Node AO-1 diagram. The devices on the left side, such as paper tape, Autodin, and other message switches are regarded as input, whereas, devices on the right side of the diagram are regarded as outputs from the message switch. This does not preclude the fact that message channels are capable of simultaneous two-way transmission. The Autodin network on the left and right sides of the diagram could be the same network access over a two-way channel. Any combination of up to fifty channels can be connected to the switch. The switch requires the use of non volatile storage for history of message activity and as a backup in case of memory failure. Since this study did not consider cryptographic and modem equipment, none is shown in the diagrams.\n\nInternal message switch processing is depicted by the top level functional decomposition model (Node AO). After switch startup, program load, and database initialization, incoming messages are received, validated for proper format, and forwarded to their final destination or other relay points. The details of this process are explained in the following paragraphs.\n\nSystem startup (A1) consists of switch initialization and sending the start command to each of the other functions of the switch. Startup is a relatively simple subset of system recovery, which will be discussed later.\n\nThe \"operator interface\" function (A2) is used to communicate with the personnel operating the system. They must be able to enter, verify, and change database information which the switch uses to determine message routing and line or trunk characteristics. Other interface commands obtain information about switch performance, cause printouts of specific messages, trace messages through the system, or exhibit various information about messages passing through the switch. The information required for the printouts comes primarily from the reference and journal files. Other operator commands deal with system shutdown, re-introduction of undeliverable messages, diagnostic capability, etc.\n\nAlthough the remaining functions of the switch operate simultaneously on up to fifty different messages, for a single message, processing may be viewed as a sequential process. Activity within the message switch is created by receipt of\nmultiple serial bit streams (message data) at the \"assemble messages\" function (A3, left side). The bit streams are converted to characters, lines, and blocks until a complete message is received. The function must be capable of dealing with several different protocols, ranging from fully asynchronous with no blocking and no acknowledgement or other control to rigidly blocked synchronous traffic with block by block acknowledgement. Received messages must be validated for proper format to eliminate garbled transmissions. High precedence messages may be passed even with some specified errors. The \"assemble messages\" function keeps a log of its operations on each message in the reference file. It also routes a complete copy of each message as it was received to the reference file, and queues received messages by precedence for \"process message\".\n\nThe \"process messages\" function (A4) obtains received messages from the input queue, determines output routing, performs any necessary translation, and queues for transmission. Once a message has been accepted and queued, a copy is routed to the \"in-transit\" file (process delineated as a subset of A4). If the \"in-transit\" file becomes filled beyond a certain threshold, incoming messages are diverted to the \"overflow\" file, and are automatically reentered into the system as the \"in-transit\" file lower threshold is reached.\n\nMessages may have more than one destination. When a message must be transmitted over more than one channel, the portion of the message containing the routing information (the routing line) must be edited to remove destinations not applicable to each individual channel. In addition, different destinations may require differing formats (JANAP-128 vs. ACP-127) or different character codes (ASCII vs. ITA#2). If so, these transformations are provided at this point. Routed messages are then sent back to the in-transit file unless the channel for the message is marked as closed, in which case the message is sent to the intercept file. Messages in the intercept file may be re-introduced on operator command.\n\nThe \"transmit messages\" function (A5) converts the routed message into a bit stream and transmits it. This function must be able to handle simultaneous operation of up to fifty lines with several different protocols. Any blocking or control characters must be added at this stage. Final validation, to include a check that the security classification limit for this line is not exceeded, is performed at this time. The transmit function also keeps a log of its activities in the journal file.\n\nThe recovery function (A1) must insure that messages being processed at the time of a system failure are not lost. To do this, the journal file is used to perform an audit of the messages received by the switch. Any message which had not completed its final delivery at the time of the failure is re-introduced into the system from the reference file, and labeled as a \"suspected duplicate\".\nIn all operations the switch must maintain high standards of reliability and throughput. The switch must operate on a priority basis, with first-in-first-out operation within precedence.\nFunctional Decomposition Models and Ada Functional Requirements\nprocedure INITIALIZE_SYSTEM is\nbegin\n --> SET UP SYSTEM TABLES FROM PROGRAM LOAD FILE\n --> (OR OPERATOR CONSOLE)\n --> CLEAR BUFFERS\n --> INITIALIZE LINE HANDLERS\nend INITIALIZE_SYSTEM;\n\nEOT..\nprocedure AUDIT_JOURNAL is\nbegin\n for all LOG ENTRIES in HISTORY_FILE loop\n case ENTRY_TYPE is\n when EOM_IN =>\n -- ADD MESSAGE_ID TO CURRENT_LIST\n when SVC_GEN =>\n -- ADD MESSAGE_ID TO CURRENT_LIST\n when EOM_OUT =>\n if LAST COPY then\n -- REMOVE MESSAGE_ID FROM CURRENT_LIST\n end if;\n when OVERFLOW OUT =>\n -- REMOVE MESSAGE_ID FROM CURRENT_LIST\n when OVERFLOW IN =>\n -- ADD MESSAGE_ID TO CURRENT_LIST\n when INTERCEPT OUT =>\n -- REMOVE MESSAGE_ID FROM CURRENT_LIST\n when INTERCEPT IN =>\n -- ADD MESSAGE_ID TO CURRENT_LIST\n when others =>\n null;\n end case;\n -- COLLECT LAST CSN FOR EACH LINE\n end loop;\nend AUDIT_JOURNAL;\nEOT..\n---A122 RECOVER INTRANSIT MESSAGES\n---REV BAAA\n---11/24/81 PD\n\nprocedure RECOVER_INTRANSIT_MESSAGES is\nbegin\n for all MESSAGES ON HISTORY TAPE loop\n if MESSAGE ID ON CURRENT LIST then\n -> ADD MESSAGE TO RECOVERED MESSAGES\n -> REMOVE MESSAGE_ID FROM CURRENT_LIST\n end if;\n end loop;\n if CURRENT LIST not EMPTY then\n -> NOTIFY OPERATOR\n end if;\nend RECOVER_INTRANSIT_MESSAGES;\n\nEOT..\nprocedure INTRANSIT_FAILURE is\nbegin\n if FIRST_FAILURE then\n -- ONE COPY OF INTRANSIT STORAGE REMAINING\n --> NOTIFY OPERATOR\n if FAILED_UNIT = CURRENT_UNIT then\n CURRENT_UNIT := BACKUP_UNIT;\n end if;\n else\n -- NO COPIES OF INTRANSIT STORAGE LEFT\n --> NOTIFY OPERATOR\n --> FAIL SYSTEM\n end if;\nend INTRANSIT_FAILURE;\n\nEOT..\nprocedure PERFORM_OVERFLOW_AUDIT is\nbegin\n for all LOG ENTRIES in HISTORY_FILE loop\n if ENTRY_TYPE = OVERFLOW_OUT then\n --> ADD MESSAGE_ID TO OVERFLOW_LIST\n elsif ENTRY_TYPE = OVERFLOW_IN then\n --> DELETE MESSAGE_ID FROM OVERFLOW_LIST\n else\n null;\n end if;\n end loop;\nend PERFORM_OVERFLOW_AUDIT;\n\nEOT.\n-- A1322 RECOVER OVERFLOW MESSAGES\n-- REV BAAAA\n-- 11/24/81 PD.\n\nprocedure RECOVER_OVERFLOW_MESSAGES is\nbegin\n for all MESSAGES ON HISTORY TAPE loop\n if MESSAGE ID ON OVERFLOW_LIST then\n --> ADD MESSAGE TO NEW OVERFLOW FILE\n --> REMOVE MESSAGE_ID FROM OVERFLOW_LIST\n end if;\n end loop;\n if OVERFLOW LIST not EMPTY then\n --> NOTIFY OPERATOR\n end if;\n end loop;\nend RECOVER_OVERFLOW_MESSAGES;\n\nEOT..\nprocedure PERFORM_INTERCEPT_AUDIT is\nbegin\n for all LOG ENTRIES in HISTORY FILE loop\n if ENTRY TYPE = INTERCEPT OUT then\n --> ADD MESSAGE_ID TO INTERCEPT_LIST\n elsif ENTRY TYPE = INTERCEPT IN then\n --> DELETE MESSAGE_ID FROM INTERCEPT_LIST\n else\n null;\n end if;\n end loop;\nend PERFORM_INTERCEPT_AUDIT;\nEOT.\nprocedure RECOVER_INTERCEPT_MESSAGES is\n begin\n for all MESSAGES ON HISTORY_TAPE loop\n if MESSAGE_ID ON INTERCEPT_LIST then\n --> ADD MESSAGE TO NEW INTERCEPT_FILE\n --> REMOVE MESSAGE_ID FROM INTERCEPT_LIST\n end if;\n end loop;\n if INTERCEPT_LIST not EMPTY then\n --> NOTIFY OPERATOR\n end if;\n end RECOVER_INTERCEPT_MESSAGES;\n\nEOT..\nprocedure HISTORY_FAILURE is\nbegin\n if A COPY of HISTORY REMAINS then\n NOTIFY OPERATOR\n RECOPY REMAINING HISTORY FOR NEW BACKUP\n else\n NOTIFY OPERATOR\n START NEW HISTORY FILE\n end if;\nend HISTORY_FAILURE;\n\nEOT...\nA311 SELECT_INPUT_DATA_TYPE\nTHE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\nTO SELECT EITHER SYNCHRONOUS OR ASYNCHRONOUS DATA PROCESSING\nDEPENDING ON THE MODE OF THE SPECIFIC MESSAGE SWITCH LINE\nAS DESCRIBED IN THE FOLLOWING:\nMANUAL PARAGRAPH(S)\nDCAC 370-D175-1 CHAPTERS 5 AND 11\n01/25/81 HF\n\nprocedure SELECT_INPUT_DATA_TYPE is\nbegin\n if CHANNEL_MODE for THIS_LINE = [2|4|5] then\n RECEIVE_VALIDASYNCHRONOUS_CHARACTERS;\n elsif CHANNEL_MODE for THIS_LINE = [1|3] then\n RECEIVE_VALID_SYNCHRONOUS_CHARACTERS;\n else\n DATABASE_INITIALIZATION_ERROR;\n end if;\nend SELECT_INPUT_DATA_TYPE;\nEOT..\nprocedure RECEIVE_VALIDASYNCHRONOUS_CHARACTERS is\n type PTY is (EVEN, ODD);\n PARITY : PTY;\n type BIT is (LOW, HIGH);\n BIT_SEQ : array(0..7) of BIT;\n pragma PACK(BIT);\n CLOCK_CYCLE : DURATION;\n FRAMING_ERROR : BOOLEAN;\nbegin\n -- ASSUMES CLOCK RATE IS 16 TIMES BAUD RATE\n -- FOR TIMING PURPOSES ASSUMES THAT INSTRUCTIONS EXECUTE IN\n -- ZERO TIME\n -- FOR IMPLEMENTATION, DELAYS MUST BE ADJUSTED FOR\n -- INSTRUCTION EXECUTION TIMES\n loop\n while ASYNCH_BIT_STREAM /= LOW loop\n delay 1.0 * CLOCK_CYCLE;\n end loop;\n delay 24.0 * CLOCK_CYCLE;\n BIT_SEQ := (0..7 => LOW);\n PARITY := EVEN;\n for I in reverse 8-LEVEL..7 loop\n BIT_SEQ(I) := ASYNCH_BIT_STREAM;\n if BIT_SEQ(I) = HIGH then\n if PARITY = EVEN then\n PARITY := ODD;\n else\n PARITY := EVEN;\n end if;\n end if;\n delay 16.0 * CLOCK_CYCLE;\n end loop;\n FRAMING_ERROR := FALSE;\n I := 1;\n loop\n if ASYNCH_BIT_STREAM = LOW then\n FRAMING_ERROR := TRUE;\n end if;\n I := I + 1;\n delay 8.0 * CLOCK_CYCLE;\n exit when I > NO_STOP_BITS;\n delay 8.0 * CLOCK_CYCLE;\n end loop;\n ASYNCH_CHAR := UNCHECKED_CONVERSION(BIT_SEQ(1..7));\n STROBE ASYNCH_CHAR;\nend loop;\nend RECEIVE_VALIDASYNCHRONOUS_CHARACTERS;\nEOT..\n-- A313 RECEIVE_VALID_SYNCHRONOUS_CHARACTERS\n-- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\n-- TO SYNCHRONIZE AND CONVERT A SERIAL BIT STREAM TO A CHARACTER\n-- ORIENTED FORMAT, AND CHECK FOR PARITY ERRORS AS DESCRIBED IN\n-- THE FOLLOWING:\n-- MANUAL\n-- DCAC 370-D175-1\n-- 02/08/82 HF\nprocedure RECEIVE_VALID_SYNCHRONOUS_CHARACTERS is\nbegin\n-- THIS REQUIREMENT IS SIMILAR IN NATURE TO A312, FOR WHICH THERE\n-- IS AN EXAMPLE. IT IS EXPECTED THAT THIS FUNCTION WILL BE\n-- IMPLEMENTED BY HARDWARE.\nend RECEIVE_VALID_SYNCHRONOUS_CHARACTERS;\nEOT.\nprocedure ANALYZE ASYNCH FRAMING is\nbegin\nif START SYSTEM COMMAND or FRAMING_ERROR then\n GENERATE CONTROL CHAR;\n -- USE RT RCVD CODE (RT)\n START OF CONTROL SEQUENCE:=FALSE;\n ASYNCH_STATE:=INTERMESSAGE;\nelsif STROBE ASYNCH_CHAR then\n if CHANNEL_MODE = 5 then\n if EXPIRED PAUSE TIMER then\n if PROTOCOL = ITA #2 or (ASCII and CHARACTER_PARITY = EVEN) then\n if RECEIVED CHARACTER = [ASYNCH RECEIVE CONTROL_CHAR | CANCEL CHAR | REPLY CHAR | START_CHAR] then\n START OF CONTROL SEQUENCE:=TRUE;\n -- Ctl Seq is effected if next consecutive\n -- Character is a repeat of this character.\n START_PAUSE_TIMER;\n -- If the pause timer expires before the next\n -- Character arrives, this sequence starts over.\n --> ACCEPT CONTROL CHARACTER\n --> Not to be intermixed with message characters.\n else\n ASYNCH_STATE:=INTERMESSAGE;\n -- IMPLIES THAT CHARACTER IS TO BE IGNORED.\n end if;\n else\n ASYNCH_STATE:=INTERMESSAGE;\n end if;\n else\n if START_OF CONTROL_SEQUENCE = TRUE then\n PROCESS ASYNCH CONTROL_SEQ;\n elsif ASYNCH_STATE = INTERMESSAGE then\n PROCESS INTERMESSAGE CHAR;\n START_PAUSE_TIMER;\n elsif ASYNCH_STATE = INTRAMESSAGE then\n PROCESS INTRAMESSAGE CHAR;\n if CHAR_BUFFER = UPPER_THRESHOLD then\n GENERATE CONTROL CHARs;\n -- USE 'SEND_STOP' REQUEST CODE\n end if;\n end if;\n end if;\n else\n if CHANNEL_MODE = 2 or 4 then\n if ASYNCH_STATE = INTERMESSAGE then\n\nPROCESS_INTERMESSAGE_CHARACTER;\nelself ASYNCH_STATE = INTRAMessage then\n PROCESS_INTRAMessage_CHAR;\nend if;\nend if;\n\ne1s1f NO CHARACTERS RECEIVED for LAST 30 MINUTES then\n GEN SVC MSG;\n -- SVC_MESSAGE_TYPE = TRAFFIC_CHECK;\nend if;\nend ANALYZEASYNCH_FRAMING;\n\nEOT..\nprocedure PROCESS_INTERMESSAGE_CHAR is\nbegin\n if PROTOCOL = ITA #2 or (ASCII and CHARACTER_PARITY = EVEN)\n then\n --> VALIDATE START OF MESSAGE SEQUENCE 'ZCZC'\n if SOM_SEQ = VALID then\n ASYNCH_STATE := INTRAMESSAGE;\n UPDATE_JOURNAL;\n -- SEND SOM_IN LOG ENTRY INFORMATION CODE\n end if;\n -- IMPLIES THAT ANY OTHER TEXT CHARACTERS WILL BE IGNORED.\n end if;\nend PROCESS_INTERMESSAGE_CHAR;\n\nEOT..\nprocedure PROCESS_INTRAMESSAGE_CHAR is\n\nbegin\n if PROTOCOL = ITA #2 then\n if CHARACTER = LETTERS CHAR then\n CHARACTER_CASE := LETTERS;\n --> ACCEPT CHARACTER\n elsif CHARACTER = FIGS CHAR then\n CHARACTER_CASE := FIGS;\n --> ACCEPT CHARACTER\n else\n --> ACCEPT CHARACTER\n end if;\n elsif PROTOCOL = ASCII then\n if CHARACTER_PARITY = ODD then\n --> ACCEPT CHARACTER\n end if;\n end if;\n\n if CHARACTER ACCEPTED then\n --> CHECK FOR VALID 'EOM' SEQUENCE (LINE FEED + NNNN)\n if VALID EOM SEQUENCE DETECTED then\n GENERATE_CONTROL_CHARS;\n --> USE EOMS_RCVD_CODE\n --> ACCEPT MESSAGE\n -- CAN BE OVERWRITTEN BY VALIDATION AND REF STORAGE.\n UPDATE_JOURNAL;\n --> SEND 'EOM IN' LOG ENTRY INFORMATION CODE\n end if;\n if CHANNEL_MODE = 5 then\n START_PAUSE_TIMER;\n end if;\n else\n ASYNCH_STATE := INTERMESSAGE;\n GENERATE_CONTROL_CHARS;\n --> USE SEND RT MESSAGE CODE. THIS WILL INITIALLY CAUSE\n -- STOP TO BE SENT OUT FROM THE XMITTER, CAUSING AN\n -- EVENTUAL REPLY TO BE RECEIVED. THEN RETRANSMIT MESSAGE\n -- (RT) WILL BE SENT OUT.\n UPDATE_JOURNAL;\n --> USE LOG_ENTRY_INFO = REJECT_ENTRY\n end if;\nend PROCESS_INTRAMESSAGE_CHAR;\n\nEOT..\n-- A3144 PROCESS ASYNCH CONTROL SEQ\n-- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\n-- FOR PROCESSING A CONTROL CHARACTER SEQUENCE FOR A MODE 5\n-- ASYNCHRONOUS TERMINAL CONNECTED TO THE MESSAGE SWITCH\n-- AS DESCRIBED IN THE FOLLOWING:\n-- MANUAL PARAGRAPH(S)\n-- DCAC 370-D175-1 CHAPTER 11\n-- 01/31/82 HF\n\nprocedure PROCESS_ASYNCH_CONTROL_SEQ is\nbegin\n if PROTOCOL = ITA_#2 or (ASCII and CHARACTER_PARITY = EVEN) then\n if CHARACTER /= PREVIOUS CONTROL_CHAR then\n ASYNCH_STATE:=INTERMESSAGE;\n -- IMPLIES THAT PAUSE TIMER WILL EXPIRE AND SEQ MUST\n -- RESTART.\n elsif CHARACTER = [STOP_CHAR | ACK_CHAR | RETRANSMIT_CHAR] then\n generate control chars;\n -- USE CODE REQUIRED BY THE CONTROL SEQUENCE, SUCH AS\n -- STOP_RCVD, ACK_1_RCVD, ACK_2_RCVD, OR RT_RCVD.\n start pause timer;\n elsif CHARACTER = CANCEL_CHAR then\n generate control chars;\n -- USE CANCEL_RCVD CODE. THIS ALSO IMPLIES THAT ACK\n -- ALTERNATION SEQUENCE IS SET TO TRANSMIT AN\n -- ACK 2 OUT OF THE TRANSMITTER.\n -- IN ADDITION, IF A STOP SEQUENCE IS IN PROGRESS, IT\n -- IS TO BE RESET.\n update journal;\n -- USE LOG_ENTRY_INFO = CANCEL_REC_ENTRY\n start pause timer;\n elsif CHARACTER = REPLY_CHAR then\n generate control chars;\n -- USE REPLY_RCVD CODE (MESSAGE STATUS ASSUMED TO\n -- BE RT UNLESS APPROPRIATELY ACKED.\n start pause timer;\n elsif CHARACTER /= START_CHAR then\n ASYNCH_STATE:=INTERMESSAGE;\n -- IMPLIES THAT CHARACTER SEQUENCE IS TO BE IGNORED.\n end if;\n else\n ASYNCH_STATE:=INTERMESSAGE;\n end if;\n end if;\n START_OF_CONTROL_SEQUENCE:=false;\nend PROCESS_ASYNCH_CONTROL_SEQ;\n\nEOT..\n-- A3151 ANALYZE BLOCK_FRAMING\n-- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\n-- TO ANALYZE SYNCHRONOUS PROTOCOL AFTER BIT AND CHARACTER\n-- SYNCHRONIZATION HAS BEEN PREVIOUSLY ESTABLISHED.\n-- AS DESCRIBED IN THE FOLLOWING:\n-- MANUAL PARAGRAPH(S)\n-- DCAC 370-D175-1 CHAPTER 5\n-- 01/19/82 HF\n\nprocedure ANALYZE_BLOCK_FRAMING is\nbegin\n if CHAR STROBE then\n if DATA SCATE LATCH = TRUE and DATA_STATE=FALSE then\n DATA_STATE:=TRUE;\n CHAR_COUNT:=1;\n START OF CONTROL SEQUENCE:=FALSE;\n elsif DATA_STATE LATCH = FALSE then\n if not PROCESS BLOCK FRAMING STATE and\n SYNCH DATA MODE::BLOCK BY_BLOCK then\n DATA_STATE:=FALSE;\n exit;\n end if;\n exit;\n end if;\n if START OF CONTROL SEQUENCE = TRUE then\n PROCESS SYNCH_CONTROL_SEQ;\n exit;\n end if;\n case CHAR_COUNT is\n when 1 =>\n PROCESS_FIRST_SYNCH_CHAR;\n when 2 =>\n PROCESS_SECOND_SYNCH_CHAR;\n when 3 .... 82 =>\n PROCESS SYNCH TEXT;\n when 83 or END OF MEDIUM SEQUENCE::TRUE =>\n PROCESS BLOCK_FRAMING;\n when 84 =>\n PROCESS_BLOCK_PARITY;\n end case;\n else\n if NO CHARACTERS RECEIVED for LAST 30 MINUTES then\n GEN SVC_MSG;\n -- SVC MESSAGE TYPE::TRAFFIC CHECK;\n -- IMPLIES RECEIVER IS EITHER OUT OF SYNC OR\n -- RECEIVING ONLY SYNC CHARACTERS.\n end if;\n end if;\nend ANALYZE_BLOCK_FRAMING;\n\nEOT..\nprocedure PROCESS_FIRST_SYNCH_CHAR is\nbegin\n if CHARACTER_PARITY = ODD then\n exit;\n end if;\n if CONTROL_CHARACTER = (REQUEST FOR ANSWER_CHAR | RECEIVE CONTROL CHAR | INVALID CHAR) then\n START_OF_CONTROL_SEQUENCE := TRUE;\n -- THE CONTROL SEQUENCE IS EFFECTED IF THE NEXT CONSECUTIVE\n -- CHARACTER IS A REPEAT OF THIS CONTROL CHARACTER.\n --> ACCEPT CHARACTER\n exit;\n end if;\n if SYNCH_DATA_MODE = BLOCK_BY_BLOCK then\n VERIFY_THAT_WE_HAVE_ANSWERED FOR THE LAST BLOCK RECEIVED;\n if WE_HAVE Not_ANSWERED then\n exit;\n end if;\n else\n if SYNCH_DATA_MODE = CONTINUOUS then\n if FIRST CHARACTER AFTER BLOCK PARITY of BLOCK in ERROR\n then\n exit;\n end if;\n end if;\n if CONTROL_CHARACTER = START_OF_HEADER then\n if ETX_BF or CANCEL not LAST_PROCESSED then\n exit;\n end if;\n elsif CONTROL_CHARACTER = START_OF_TEXT then\n if ETB_BF not LAST_CHARACTER_PROCESSED then\n exit;\n end if;\n else\n exit;\n end if;\n --> ACCEPT FIRST CHARACTER\n UPDATE_JOURNAL;\n -- USE SOM_IN_ENTRY.\n CHAR_COUNT := CHAR_COUNT + 1;\n end if;\nend PROCESS_FIRST_SYNCH_CHAR;\n\nEOT..\n-- A3153 PROCESS SECOND SYNCH CHAR\n-- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\n-- FOR PROCESSING THE SECOND CHARACTER OF A SYNCHRONOUS INPUT\n-- TRUNK TO THE MESSAGE SWITCH AS DESCRIBED IN THE FOLLOWING:\n-- MANUAL PARAGRAPH(S)\n-- DCAC 370-D175-1 CHAPTER 5\n-- 01/17/82 HF\n\nprocedure PROCESS_SECOND_SYNCH_CHAR is\nbegin\n if CHARACTER_PARITY = ODD then\n CHAR_COUNT:=1;\n exit;\n end if;\n if FIRST_CHARACTER = START_OF_HEADER_CHAR then\n if CONTROL_CHARACTER = SELECT_CHAR then\n -- > ACCEPT SECOND_CHARACTER\n else\n GENERATE_CONTROL_CHARS;\n -- USE SEND_RM CODE\n end if;\n else\n if FIRST_CHARACTER = START_OF_TEXT_CHAR then\n if AUTODIN_INTERSWITCH TRUNK then\n if VALID_SECURITY_CHARACTER then\n -- > ACCEPT SECOND_CHARACTER\n else\n GENERATE_CONTROL_CHARS;\n -- USE SEND_RM CODE\n end if;\n elsif DELETE_CHAR then\n -- > ACCEPT SECOND_CHARACTER\n else\n GENERATE_CONTROL_CHARS;\n -- USE SEND_RM CODE\n end if;\n end if;\n end if;\n if SECOND_CHARACTER ACCEPTED then\n CHAR_COUNT:=CHAR_COUNT+1;\n BP_CALC:=SECOND_CHARACTER;\n end if;\nend PROCESS_SECOND_SYNCH_CHAR;\nEOT..\nprocedure PROCESS_SYNCH_TEXT is\nbegin\n if CHARACTER_PARITY = EVEN then\n if CONTROL_CHARACTER = MODE_CHANGE_CHAR or\n END_OF_MEDIUM_CHAR then\n --> ACCEPT CHARACTER\n CHAR_COUNT := CHAR_COUNT + 1;\n BLOCK_PARITY_CALC := BLOCK_PARITY_CALC xor CONTROL_CHAR;\n if CONTROL_CHARACTER = END_OF_MEDIUM then\n END_OF_MEDIUM_SEQ := TRUE;\n end if;\n elseif CONTROL_CHARACTER = [RECEIVE_CONTROL_CHAR ;\n INVALID CHAR] then\n START_OF_CONTROL_SEQ := TRUE;\n -- THE CONTROL SEQUENCE IS EFFECTED IF THE NEXT\n -- CONSECUTIVE CHARACTER IS IDENTICAL TO THIS ONE.\n --> ACCEPT CHARACTER\n else\n CHAR_COUNT := 1;\n GENERATE_CONTROL_CHARS;\n --> USE SEND_NAK CODE (TO BE OUTPUT ONLY AFTER BLOCK\n -- FRAMING, REPLY, OR CANCEL)\n end if;\n elseif TEXT_CHARACTER then\n --> ACCEPT CHARACTER\n CHAR_COUNT := CHAR_COUNT + 1;\n BP_CALC := CHAR_COUNT + 1;\n BP_CALC := BP_CALC xor TEXT_CHARACTER;\n end if;\nend PROCESS_SYNCH_TEXT;\nEOT.\n-- A3155 PROCESS BLOCK_FRAMING\n-- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\n-- FOR PROCESSING THE BLOCK FRAMING CHARACTER POSITION OF A\n-- SYNCHRONOUS INPUT TRUNK TO THE MESSAGE SWITCH\n-- AS DESCRIBED IN THE FOLLOWING:\n-- MANUAL PARAGRAPHS\n-- DCAC 370-D175-1 CHAPTER 5\n-- 01/19/82 HF\n\nprocedure PROCESS_BLOCK_FRAMING is\n begin\n if CHARACTER_PARITY = EVEN then\n if CONTROL_CHARACTER = ETX CHAR or ETB CHAR then\n if PREVIOUSLY RECEIVED BLOCK HAS BEEN ACKNOWLEDGED then\n -> ACCEPT CHARACTER\n BP_CALC:=BP_CALC xor CONTROL_CHAR;\n if ETX_CHAR then\n END OF MESSAGE_SEQ:=TRUE;\n end if;\n else\n CHAR_COUNT:=1;\n -- IMPLIES THAT TRANSMITTER IS NOT KEEPING UP.\n -- GOOD AREA TO APPLY AUTOMATIC ERROR DETECTION.\n end if;\n else\n CHAR_COUNT:=1;\n -- IMPLIES THAT CHARACTER WAS NOT ACCEPTED; WAIT FOR\n -- REPLY OR CANCEL.\n end if;\n else\n CHAR_COUNT:=1;\n -- IMPLIES THAT CHARACTER WAS NOT ACCEPTED; WAIT FOR\n -- OR CANCEL.\n end if;\n end if;\n END OF MEDIUM_SEQ:=FALSE;\nend PROCESS_BLOCK_FRAMING;\n\nEOT.\nprocedure PROCESS_SYNCH_CONTROL_SEQ is\nbegin\n if CONTROL_CHARACTER /= PREVIOUS CONTROL_CHARACTER then\n if CHAR_COUNT > 1 then\n GENERATE_CONTROL_CHARS;\n CHAR_COUNT := 1;\n end if;\n elsif CONTROL_CHARACTER = INVALID_CHAR then\n GENERATE_CONTROL_CHARS;\n USE INVALID_RCVD CODE\n elsif CONTROL_CHARACTER = RECEIVE_CONTROL_CHAR then\n GENERATE_CONTROL_CHARS;\n USE CODE REQUIRED BY CONTROL CHAR, SUCH AS WBT_RCVD,\n NAK_RCVD, RM_RCVD, ACK_1_RCVD OR ACK_2_RCVD.\n elsif PROCESSING_SYNCH_TEXT_STATE then\n GENERATE_CONTROL_CHARS;\n USE INVALID_CHAR CODE\n CHAR_COUNT := 1;\n CHANGES STATE TO PROCESS FIRST SYNCH CHAR\n elsif CONTROL_CHARACTER = REQUEST_FOR_ANSWER_CHAR then\n GENERATE_CONTROL_CHARS;\n USE CODE AS REQUIRED BY CONTROL CHARACTER, SUCH AS\n [REPLY RECEIVED | CANCEL RECEIVED | ENQUIRY RECEIVED]\n AND REPORT THAT AN ANSWER IS REQUIRED.\n if CONTROL_CHARACTER = CANCEL_CHAR then\n UPDATE_JOURNAL;\n USE CANCEL_RECEIVED CODE\n end if;\nend if;\nSTART_OF_CONTROL_SEQUENCE := FALSE;\nend PROCESS_SYNCH_CONTROL_SEQ;\n\nEOT.\n-- A3157 PROCESS BLOCK PARITY\n-- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\n-- TO CHECK THE BLOCK PARITY CHARACTER OF A SYNCHRONOUS\n-- MESSAGE AND TAKE APPROPRIATE ACTION BASED ON THE RESULT\n-- AS DESCRIBED IN THE FOLLOWING:\n-- MANUAL PARAGRAPH(S)\n-- DCAC 370-D175-1 CHAPTER 5\n-- 01/21/82 HF\n\nprocedure PROCESS_BLOCK_PARITY is\nbegin\n if BP CALC = CONTROL_CHAR then\n if END OF MESSAGE SEQ = TRUE then\n -- ACCEPT CHARACTER\n -- ACCEPT MESSAGE\n -- COMMENT FOR ACCEPT BLOCK ALSO APPLIES HERE.\n END_OF_MESSAGE_SEQ:=FALSE;\n else\n -- ACCEPT CHARACTER\n -- ACCEPT BLOCK\n -- CAN BE OVERRIDEN BY MESSAGE VALIDATION ROUTINES\n -- AND REFERENCE STORAGE. TIME CONSTRAINTS EXIST FOR\n -- A REPLY, AS WELL AS SYNCHRONIZATION OF THE PROCESSES.\n end if;\n CHAR_COUNT:=1;\n GENERATE_CONTROL_CHARS;\n -- USE EOMS RCVD_CODE\n UPDATE_JOURNAL;\n -- USE EOM_IN CODE\n else\n CHAR_COUNT:=1;\n GENERATE_CONTROL_CHARS;\n -- USE SEND_RM_CODE\n -- WAIT FOR REPLY OR CANCEL.\n end if;\nend PROCESS_BLOCK_PARITY;\n\nEOT..\nprocedure DECIDE_CHECK_SEQUENCE is\nbegin\n if PRECEDENCE = [W|Y|Z] then\n if CHANNEL_MODE = [2|4] then\n ECSN := ECSN + 1;\n end if;\n COMPLETE TI;\n elsif CHANNEL_MODE = [2|4] then\n CHECK MODE TI IV_CSN;\n elsif CHANNEL_MODE = 5 then\n CHECK MODE V_CSN;\n end if;\nend DECIDE_CHECK_SEQUENCE;\n\nEOT..\nprocedure CHECK_MODE_II_IV_CSN is\nbegin\n if ICSN(1..3) not in digits then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INCORRECT_CSN, MESSAGE_ID));\n ECSN := ECSN + 1;\n elsif ICSN /= ECSN then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INCORRECT_CSN, MESSAGE_ID));\n ECSN := ICSN + 1;\n else\n if LAST_GOOD_CSN + 1 /= ICSN then\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (OPEN_CSN, MESSAGE_ID, LAST_GOOD_CSN, ICSN));\n end if;\n LAST_GOOD_CSN := ICSN;\n ECSN := ICSN + 1;\n end if;\nend CHECK_MODE_II_IV_CSN;\nprocedure CHECK_MODE_V_CSN is\nbegin\n if ICSN(1..3) not in digits then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INCORRECT_CSN, MESSAGE_ID));\n LAST_CSN_REJ := FALSE;\n elsif ICSN /= ECSN and ((LAST_CSN_REJ and ICSN /= IRCSN) or\n not LAST_CSN_REJ) then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INCORRECT_CSN, MESSAGE_ID));\n LAST_CSN_REJ := TRUE;\n IRCSN := ICSN;\n else\n if LAST_GOOD_CSN +1 /= ICSN then\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (OPEN_CSN, MESSAGE_ID,, LAST_GOOD_CSN, ICSN));\n end if;\n LAST_CSN_REJ := FALSE;\n LAST_GOOD_CSN := ICSN;\n end if;\nend CHECK_MODE_V_CSN;\n\nEOT.\nprocedure CHECK_ICD is\nbegin\n if ICD /= CHNL DES then\n GENERATE_CONTROL_CHARACTER( REJECT MESSAGE,MESSAGE_ID);\n GENERATE_SERVICE_MESSAGE(SERVICE MESSAGE_INFO => INVALID_HEADER_REJ,MESSAGE_ID));\n end if;\nend CHECK_ICD;\n\nEOT..\nprocedure COMPLETE_TI is\nbegin\n --> TI LINE MUST NOT EXCEED 79 CHARACTERS\n --> STARTING WITH ICD AND ENDING WITH FIRST LF\n --> TI LINE MUST END IN LOWER CASE IF ITA\n --> MINIMUM END OF LINE IS ONE LF\n if any of ABOVE not MET then\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_HEADER_REJ,MESAGE_ID) );\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESAGE_ID);\n --> TERMINATE PROCESSING ON THIS MESSAGE\n end if;\nend COMPLETE_TI;\n\nEOT..\nprocedure DETECT_CANTRAN is\nbegin\n if ACP 127 or (JANAP_128 and FIRST_LMF_CHARACTER /= [S;C;B;D ;I]) then\n START := INDEX of EOM SEQUENCE; -- LF NNNN\n FINI := START - 23;\n for I in reverse FINI..START loop\n exit when MESSAGE(I) = '#';\n if MESSAGE(I..I+3) = \"E E AR\" then\n -- > MAKE CANTRAN REC LOG ENTRY\n -- > DISCARD MESSAGE\n -- > NOTIFY OPERATOR\n -- > TERMINATE PROCESSING ON THIS MESSAGE\n exit;\n end if;\n end loop;\n end if;\nend DETECT_CANTRAN;\n\nEOT..\nprocedure GENERATE ASYNCH_CTL_CHARS is\nbegin\n if REPLY TIMER (2-4 SECONDS) = EXPIRED then\n if MESSAGE STATUS = CANCEL SEQ then\n CONTROL_CODE:=CANCEL_SENT;\n elsif MESSAGE STATUS = REPLY SEQ then\n CONTROL_CODE:=REPLY_SENT;\n else\n raise exception;\n end if;\n end if;\n if STOP TIMER (2-8 SECONDS) = EXPIRED then\n CONTROL_CODE:=SEND_STOP;\n end if;\n case CONTROL_CODE is\n when SEND_RT =>\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n -- TRANSMIT STOP CODE\n START_STOP_TIMER;\n -- EXPECT REPLY SEQUENCE\n MESSAGE_STATUS:=RT;\n when SEND_STOP =>\n if CHAR_BUFFER < LOWER THRESHOLD then\n if MESSAGE_STATUS = RT then\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n -- TRANSMIT RT_CODE\n MESSAGE_STATUS:=NOT_STOP_SEQ;\n elsif MESSAGE_STATUS = OK then\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n -- TRANSMIT ACK_SEQ_REPLY (ACK_1 OR ACK_2)\n -- ALTERNATE ACK_SEQ_REPLY\n elsif MESSAGE_STATUS = INCOMPLETE then\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n -- TRANSMIT STOP_CODE\n MESSAGE_STATUS:=STOP_SEQ;\n -- CHECK FOR THIRD STOP TRANSMITTED AND NOTIFY\n -- OPERATOR IF SO.\n else\n raise exception;\n end if;\n elsif MESSAGE_STATUS = STOP SEQ then\n if THIRD STOP TRANSMITTED then\n -- NOTIFY OPERATOR\n end if;\n else\n raise exception;\n end if;\n else\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n -- TRANSMIT STOP_CODE\n MESSAGE_STATUS:=STOP_SEQ;\n end case;\nend procedure\nend if;\nend if;\n\nwhen ACK_SEND =>\nSEND ACKNOWLEDGEMENT RESPONSE;\n-- TRANSMIT ACK_SEQ_REPLY (TWO ACK_1 OR ACK_2 CHARACTERS\n-- ALTERNATING\n-- BETWEEN MESSAGE TRANSMISSIONS.\nACK_SEQ_REPLY:=ALTERNATE of ACK_1 or ACK_2;\nwhen CANCEL RCVD =>\nACK_SEQ_XPTD:=ACK 2;\nSEND ACKNOWLEDGEMENT RESPONSE;\n-- STOP MESSAGE TRANSMISSION (IF ANY)\nRESET STOP TIMER (IF SET);\n--> AND CLEAN UP FOR NEXT MESSAGE.\nwhen REPLY RCVD =>\nif MESSAGE_STATUS = STOPPED then\nSEND ACKNOWLEDGEMENT RESPONSE;\n-- TRANSMIT STOP CODE\nif THIRD STOP TRANSMITTED then\n--> NOTIFY OPERATOR\nelsif MESSAGE_STATUS = RT then\nSEND ACKNOWLEDGEMENT RESPONSE;\n-- TRANSMIT RT CODE\nelsif MESSAGE_STATUS = OK then\nSEND ACKNOWLEDGEMENT RESPONSE;\n-- TRANSMIT ACK_SEQ_REPLY\nACK_SEQ_REPLY:=ALTERNATE of ACK_SEQ_REPLY;\nend if;\nend if;\nwhen RT_RCVD =>\nSEND ACKNOWLEDGEMENT RESPONSE;\n-- STOP MESSAGE TRANSMISSION\nACK_SEQ_XPTD:=ACK 2;\n--> PREPARE MESSAGE FOR RETRANSMISSION AND WAIT\nMESSAGE_STATUS:=EOMS_NOT_OUTSTANDING and NOT_REPLY_SEQ;\nwhen STOP_RCVD =>\nif MESSAGE_STATUS = CANCEL_SEQ then\nCONTROL_CODE:=CANCEL_SENT;\nend if;\nSEND ACKNOWLEDGEMENT RESPONSE;\n-- STOP MESSAGE TRANSMISSION\nSTART STOP TIMER;\nwhen EOMS_CODE_SENT =>\nSTART REPLY_TIMER;\nREPEAT_COUNTER:=REPEAT_COUNTER+1;\nMESSAGE_STATUS:=EOMS_OUTSTANDING;\nwhen EOMS_CODE_RCVD =>\nif CHARACTER_BUFFER > UPPER THRESHOLD then\nSEND ACKNOWLEDGEMENT RESPONSE;\n-- TRANSMIT STOP_CODE\nSTOP_SEQ:=TRUE;\nelse\nif MESSAGE_STATUS = COMPLETE then\nif MESSAGE_STATUS = RT then\nSEND_ACKNOWLEDGEMENT_RESPONSE;\n-- TRANSMIT RT_CODE\nelsif MESSAGE_STATUS = OK then\nSEND_ACKNOWLEDGEMENT_RESPONSE;\n-- TRANSMIT ACK_SEQ_REPLY (ACK_1 OR ACK_2)\nelse\n raise exception;\nend if;\nMESSAGE_STATUS:=EOMS_RCV;\nend if;\nend if;\nwhen REPLY_SENT =>\n START_REPLY_TIMER;\n REPEAT_COUNTER:=REPEAT_COUNTER+1;\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n-- TRANSMIT REPLY_CODE\n MESSAGE_STATUS:=REPLY_SEQ;\nwhen ACK_1_RCVD =>\n REPEAT_COUNTER:=0;\n RESET_REPLY TIMER;\n if ACK_SEQ_XPTD:= ACK_1_RCVD then\n ---> CONTINUE MESSAGE TRANSMISSION\n else\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n -- CANCEL MESSAGE\n ---> PREPARE TO RETRANSMIT\n end if;\n ACK_SEQ_XPTD:=ACK_2;\n MESSAGE_STATUS:=EOMS_NOT_OUTSTANDING and NOT_REPLY_SEQ;\nwhen ACK_2_RCVD =>\n REPEAT_COUNTER:=0;\n RESET_REPLY_TIMER;\n if ACK_SEQ_XPTD = ACK_2_RCVD then\n ---> CONTINUE MESSAGE TRANSMISSION\n else\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n -- CANCEL MESSAGE\n ---> PREPARE TO RETRANSMIT\n end if;\n ACK_SEQ_XPTD:=ACK_1;\n MESSAGE_STATUS:=EOMS_NOT_OUTSTANDING and NOT_CANCEL_SEQ\n and NOT_REPLY_SEQ;\nwhen CANCEL_SENT =>\n if MESSAGE_STATUS = EOMS_NOT_OUTSTANDING then\n MESSAGE_STATUS:=CANCEL_SEQ;\n ACK_SEQ_REPLY:=ACK_2;\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n -- TRANSMIT CANCEL_CODE\n if REPEAT_COUNTER = 3 then\n ---> SET_OPERATOR_ALARM\n end if;\n else\n MESSAGE_STATUS:=REPLY_SEQ;\n SEND_ACKNOWLEDGEMENT_RESPONSE;\n -- TRANSMIT REPLY_CODE\n end if;\n\n50\nend if;\nSTART_REPLY_TIMER;\nREPEAT_COUNTER:=REPEAT_COUNTER + 1;\nend case;\nend GENERATE_ASYNCH_CTL_CHARS;\n\nEOT..\nprocedure ROUTE_TO_VALIDATION is\nbegin\n if JANAP_128 then\n if PRECEDENCE = [W;Y;Z] then\n VALIDATE_HIPREC_JANAP_128;\n else\n VALIDATE_JANAP_128;\n end if;\n else -- ACP-127\n if DOUBLE PRECEDENCE_PROSIGN(1) = [Y;Z] or\n DOUBLE PRECEDENCE_PROSIGN(2) = [Y;Z] or\n A (GARbled) BELL SIGNAL IS PRESENT then\n VALIDATE_HIPREC_ACP_127;\n else\n VALIDATE_ACP_127;\n end if;\n end if;\nend ROUTE_TO_VALIDATION;\n\nEOT...\nprocedure CHECK_128_HEADER is\nbegin\n if PRECEDENCE /= [O|P|R] then\n raise INVALID_HEADER_REJ;\n end if;\n if LMF PAIR not LEGAL then\n --LEGAL PAIRS ARE LISTED IN THE DATA DICTIONARY\n raise INVALID_HEADER_REJ;\n end if;\n if CLASS /= [M|A|T|S|C|R|E|U] then\n raise INVALID_SCTY_FIELD;\n end if;\n if CLASS >= LINE_DATA_SECURITY_PROSIGN then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (SCTY_MISMATCH,MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n end if;\n if not SINGLE_CARD then\n if REDUNDANT_CLASS(I..4) /= CLASS then\n raise INVALID_SCTY_FIELD;\n end if;\n end if;\n if CIC_CAI(1..3) not in LETTER or CIC_CAI(4) not in [LETTER !DIGIT] then\n raise INVALID_HEADER_REJ;\n end if;\n if OSRI(1..7) not in LETTER then\n raise INVALID_HEADER_REJ;\n end if;\n if OSSN(1..4) not in DIGIT then\n raise INVALID_HEADER_REJ;\n end if;\n if DATE_TIME (1..7) not in DIGIT then\n raise INVALID_HEADER_REJ;\n end if;\n --> CHECK SENTINELS AND SIGNALS\n --> BLANKS IN POS 9 & 21\n --> '-' IN POS 28 (33 IF RECORD COUNT PRESENT)\n --> '--' IN POS 33 (38 IF RECORD COUNT PRESENT)\n --> IF ANY ARE BAD RAISE INVALID_HEADER_REJ;\nexception\n when INVALID_HEADER_REJ =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_HEADER_REJ,MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1|3] then\n CALL GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID );\n end if;\nend if;\nwhen INVALID_SCTY_FIELD =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_SCTY_FIELD, MESSAGE_ID));\n ---> TERMINATE PROCESSING ON THIS MESSAGE\nif CHANNEL_MODE = [1:3] then\n CALL GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\nend if;\nend CHECK_128_HEADER;\n\nEOT..\nprocedure CHECK_RECORD_COUNT is\nbegin\n if RECORD_COUNT /= [\"MTMS\";\"PLTS\"] then\n if RECORD_COUNT /= VALID_RI then\n raise INVALID_HEADER_REJ;\n end if;\n elsif RECORD_COUNT(1) in digits then\n if RECORD_COUNT(2..4) not in digits then\n raise INVALID_HEADER_REJ;\n end if;\n if RECORD_COUNT < 3 or RECORD_COUNT > 500 then\n raise INVALID_HEADER_REJ;\n end if;\n else\n raise INVALID_HEADER_REJ;\n end if;\nexception\n when INVALID_HEADER_REJ =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_HEADER_REJ, MESSAGE_ID));\n -- > TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [113] then\n CALL GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n end if;\nend CHECK_RECORD_COUNT;\nEOT..\nprocedure CHECK_RIS is\nbegin\n loop\n --> FIND NEXT RI\n if A DELIMITER OTHER THAN [`B`|CR|LF] is FOUND then\n raise INVALID_RI_FIELD;\n end if;\n exit when END_OF_ROUTING is FOUND;\n -- END_OF_ROUTING IS '.' FOR JANAP-128\n -- AND CR CR LF Z OR CR CR LF D FOR ACP-127\n if RI(1..4) not in LETTER then\n raise INVALID_RI_FIELD;\n end if;\n if RI(1..4) = OUR RI then\n --> CHECK ENTIRE RI FOR VALIDITY\n elsif RI(3..4) = \"CR\" then\n --> CHECK RI FOR VALID COLLECTIVE RI\n else\n --> CHECK RI(1..) FOR VALID RELAY RI\n end if;\n if RI GOOD then\n --> ADD RI TO VALID_RI_LIST\n else\n --> ADD RI TO INVALID_RI_LIST\n end if;\n end loop;\n if VALID_RI_LIST is EMPTY then\n raise ALL_RI_INVALID;\n elsif INVALID_RI_LIST not EMPTY then\n raise INVALID_RI;\n end if;\n if ACP-127 and END_OF_ROUTING = CR CR LF Z then\n --> RETURN TO CHECK_127_HEADER (THIS LINE WAS A PILOT)\n end if;\nexception\n when INVALID_RI_FIELD =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_RI_FIELD,MESSAGE_ID));\n --> TERMINATE MESSAGE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1:3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n when ALL_RI_INVALID =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (ALL_RI_INVALID,MESSAGE_ID,INVALID_RI_LIST));\n --> TERMINATE MESSAGE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1:3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n when INVALID_RI =>\nCALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n(INVALID_RI, MESSAGE_ID, INVALID_RI_LIST));\nif PRECEDENCE = ['W', 'Y', 'Z'] then\n CIC_CA1(4) := 'W';\nend if;\nend CHECK_RIS;\nEOT..\nprocedure CHECK_EOM is\nbegin\n if OSSN /= EOM_VALIDATION(2.5) then\n -- USE ACP-SSN FOR ACP-127\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (SUSPECTED_STRAGGLER, MESSAGE_ID));\n if PRECEDENCE = [W,Y,Z] then\n CIC:CAI(4) := 'W';\n else\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n end if;\n end if;\n elsif EOM_SEQ DOES not CONTAIN LF \"NNNN\" then\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_EOM_REJ, MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n end if;\n end if;\n if PRECEDENCE = [W,Y,Z] then\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (HIGH_PRECEDENCE_ACCEPTANCE, MESSAGE_ID));\n end if;\n if CHANNEL_MODE = 5 then\n ECSN := ECSN + 1;\n end if;\nend CHECK_EOM;\n\nEOT..\nprocedure CHECK_EOT is\nbegin\n if not SINGLE_CARD then\n if EOT_CARD.OSSN /= ACP_SSN then\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (SUSPECTED_STRAGGLER, MESSAGE_ID));\n if PRECEDENCE = [X|Y|Z] then\n CIC_CAI(4) := 'W';\n else\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1:3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID)\n end if;\n end if;\n end if;\n end if;\n if JANAP_FMT_LN_2.RECORD_COUNT = \"PLTS\" then\n if EOT_CARD.RECORD_COUNT < 3 or EOT_CARD.RECORD_COUNT >\n 500 then\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_EOM_REJ, MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE;\n if CHANNEL_MODE = [1:3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID)\n end if;\n end if;\n else if JANAP_FMT_LN_2.RECORD_COUNT = \"MTMS\" then\n if EOT_CARD.RECORD_COUNT 7= \"MTMS\" and\n EOT_CARD.RECORD_COUNT /= ACTUAL_RECORD_COUNT then\n -- THIS IMPLIES YOU MUST COUNT THE ACTUAL NUMBER OF\n -- RECORDS\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_EOM_REJ, MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1:3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID)\n end if;\n end if;\n else\n if EOT_CARD.RECORD_COUNT /= ACTUAL_RECORD_COUNT then\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_EOM_REJ, MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1:3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID)\n end if;\n end if;\n end if;\nend if;\nend if;\nelse\n if SINGLE_CARD(80) /= 'N' then\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_FROM_REJ, MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n end if;\n end if;\n end if;\n if PRECEDENCE = ['W'|'Y'|'Z'] then\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (HIGH_PRECEDENCE_ACCEPTANCE, MESSAGE_ID));\n end if;\n end if;\n if CHANNEL_MODE := 5 then\n ECSN := ECSN + 1;\n end if;\nend CHECK_EOT;\n\nEOT..\nprocedure CHECK_127_HEADER is\nbegin\n if DOUBLE_PRECEDENCE_PROSIGN /= [\"00\";\"PP\" ;\"RR\"] then\n DOUBLE_PRECEDENCE_PROSIGN := \"00\";\n end if;\n if ACP_FMT_LN 2(3) /= 'b' then\n CALL_GENERATED_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_HEADER_REJ,MESSAGE_ID));\n -- > TERMINATE PROCESSING FOR THIS MESSAGE\n if CHANNEL_MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n end if;\nend CHECK_127_HEADER;\n\nEOT..\nprocedure CHECK_RIS is\n loop\n --> FIND NEXT RI\n if A DELIMITER OTHER THAN [\"B\", CR; LF] is FOUND then\n raise INVALID_RI_FIELD;\n end if;\n exit when END OF ROUTING is FOUND;\n -- END OF ROUTING IS ' ' FOR JANAP-128\n -- AND CR-CR LF Z OR CR LF D FOR ACP-127\n if RI(1..4) not in LETTER then\n raise INVALID_RI_FIELD;\n end if;\n if RI(1..4) = OUR RI then\n --> CHECK ENTIRE RI FOR VALIDITY\n elsif RI(3..4) = \"CR\" then\n --> CHECK RI FOR VALID COLLECTIVE RI\n else\n --> CHECK RI(1..) FOR VALID RELAY RI\n end if;\n if RI GOOD then\n --> ADD RI TO VALID_RI_LIST\n else\n --> ADD RI TO INVALID_RI_LIST\n end if;\n end loop;\n if VALID_RI_LIST is EMPTY then\n raise ALL_RI_INVALID;\n elsif INVALID_RI_LIST not EMPTY then\n raise INVALID_RI;\n end if;\n if ACP-127 and END OF ROUTING = CR CR LF Z then\n --> RETURN TO CHECK_127_HEADER (THIS LINE WAS A PILOT)\n end if;\n exception\n when INVALID_RI_FIELD =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_RI_FIELD, MESSAGE_ID));\n --> TERMINATE MESSAGE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n end if;\n when ALL_RI_INVALID =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (ALL_RI_INVALID, MESSAGE_ID, INVALID_RI_LIST));\n --> TERMINATE MESSAGE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n end if;\n when INVALID_RI =>\n raise INVALID_RI\nCALL GENERATE SERVICE MESSAGE(SERVICE_MESSAGE_INFO =>\n(INVALID RI, MESSAGE_ID, INVALID RI LIST));\nif PRECEDENCE = ['W' ! 'Y' ! 'Z'] then\n CIC_CA1(4) := 'W';\nend if;\nend CHECK_RIS;\n\nEOT..\nprocedure COMPLETE_127_HEADER is\nbegin\n if ACP SSN PRECEDED BY '#' then\n --> RETAIN FOR EOM CHECK\n end if;\n --FMT_LN 4\n if OP_SIGNAL /= ['ZNY'..'ZNR'] or CLASS X5 /= ['MMMMM'..'AAAAA'\n [TTTTT'..'SSSSS'..'CCCCCC'..'RRRRR'..'EEEEE'..'UUUUU'] then\n call generate service message (service message info =>\n (INVALID SCTY FIELD,MESSAGE ID));\n --> TERMINATE PROCESSING FOR THIS MESSAGE\n end if;\n if CHANNEL MODE = [113] then\n generate_control_character(reject_message,MESSAGE_ID);\n end if;\n if CLASS >= LINE_DATA_SECURITY_PROSIGN then\n generate_control_character(REJECT_MESSAGE,MESSAGE_ID);\n generate_service_message(service_message_info =>\n (SCTY MISMATCH,MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n end if;\nend COMPLETE_127_HEADER;\nEOT.\n\nprocedure CHECK_EOM is\nbegin\n if OSSN /= EOM VALIDATION(2..5) then\n -- USE ACP_SSN FOR ACP-127\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (SUSPECTED_STRAGGLER, MESSAGE_ID));\n if PRECEDENCE = [W;Y;Z] then\n CIC_CAI(4) := 'W';\n else\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n end if;\n elsif EOM_SEQ DOES not CONTAIN LF & \"NNNN\" then\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_EOM_REJ,MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n end if;\n if PRECEDENCE = [W;Y;Z] then\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (HIGH_PRECEDENCE_ACCEPTANCE,MESSAGE_ID));\n end if;\n if CHANNEL_MODE = 5 then\n ECSN := ECSN + 1;\n end if;\nend CHECK_EOM;\n\nEOT..\nA3341\nCHECK LMF\n\nA3342\nCHECK HP 128 HEADER\n\nA3343\nCHECK RECORD COUNT\n\nA3344\nMessage Rejections\n\nA3345\nService Message Info.\n(A3324)\n(A3334)\n(A3354)\n\nA3346\nCHECK EOT\n\nA334\nVALIDATE HI PREC JANAP-128\nprocedure CHECK_LMF is\nbegin\n case FIRST_LMF_CHARACTER is\n when 'A' =>\n if SELECT_CHARACTER = ['H'|'S'] then\n LMF_OK := TRUE;\n else\n LMF_OK := FALSE;\n end if;\n when 'B'|'D'|'I' =>\n if SELECT_CHARACTER = ['B'|'C'] then\n LMF_OK := TRUE;\n else\n LMF_OK := FALSE;\n end if;\n when 'C'|'S' =>\n if SELECT_CHARACTER = ['D'|'F'] then\n LMF_OK := TRUE;\n else\n LMF_OK := FALSE;\n end if;\n when 'F'|'Q'|'R'|'V' =>\n if SELECT_CHARACTER = 'A' then\n LMF_OK := TRUE;\n else\n LMF_OK := FALSE;\n end if;\n when others =>\n LMF_OK := FALSE;\n end case;\n if not LMF_OK then\n case SELECT_CHARACTER is\n when A =>\n FIRST_LMF_CHARACTER := 'T';\n when 'B'|'C' =>\n FIRST_LMF_CHARACTER := 'B';\n when 'D'|'F' =>\n FIRST_LMF_CHARACTER := 'C';\n when 'H'|'S' =>\n FIRST_LMF_CHARACTER := 'A';\n end case;\n CIC_CA1(4) := 'W';\n end if;\nend CHECK_LMF;\n\n--> CHECK FOR LEGAL LMF PAIR (LEGAL PAIRS ARE LISTED IN THE\n-- DATA DICTIONARY)\nif not LEGAL_PAIR then\n if FIRST_LMF_CHARACTER = ['R'|'Q'|'F'] then\n SECOND_LMF_CHARACTER := 'T';\n elsif FIRST_LMF_CHARACTER = 'S' then\n SECOND_LMF_CHARACTER := 'C';\nelse\n SECOND_LMF_CHARACTER := FIRST_LMF_CHARACTER;\nend if;\nCIC_CA(4) := 'W';\nend if;\nend CHECK_LMF;\n\nEOT.\nprocedure CHECK_HP_128_HEADER is\nbegin\n --> SECURITY FIELD 3 OUT OF 5 CHECK\n --> 3 OF THE 5 SECURITY CHARACTERS MUST BE CORRECT AND MATCH\n --> ELSE GENERATE INVALID SCTY FIELD SERVICE MESSAGE AND\n --> TERMINATE AND REJECT MESSAGE\n if CLASS (MATCHING 3) >= LINE_DATA.SECURITY_PROSIGN then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (SCTY_MISMATCH,MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n end if;\n if OSRI(1..4) = OUR RI then\n --> CHECK ENTIRE RI FOR VALID TRIBUTARY\n if not VALID then\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_HEADER_REJ,MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [113] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n end if;\n end if;\n else\n --> CHECK OSRI(1..4) FOR VALID RELAY\n if not VALID then\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_HEADER_REJ,MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [113] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n end if;\n end if;\n --> CHECK OSSN FOR EMBEDDED SPACES OR HYPHENS\n if FOUND then\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_HEADER_REJ,MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [113] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n end if;\n --> CHECK SENTENALS & SIGNALS\n --> BLANKS IN POS 9 & 21\n --> '-' IN POS 28 (33 IF RECORD COUNT PRESENT)\n --> '--' IN POS 33 (38 IF RECORD COUNT PRESENT)\n --> GENERATE INVALID HEADER REJ IF ANY ARE BAD\n --> TERMINATE AND REJECT MESSAGE\nend CHECK_HP_128_HEADER;\nEOT..\nprocedure CHECK_RECORD_COUNT is\nbegin\n if RECORD_COUNT /= [\"MTMS\";\"PLTS\"] then\n if RECORD_COUNT(1) in LETTERS then\n if RECORD_COUNT(1) = VALID RI then\n raise INVALID_HEADER_REJ;\n end if;\n elsif RECORD_COUNT(1) in digits then\n if RECORD_COUNT(2..4) not in digits then\n raise INVALID_HEADER_REJ;\n end if;\n if RECORD_COUNT < 3 or RECORD_COUNT > 500 then\n raise INVALID_HEADER_REJ;\n end if;\n else\n raise INVALID_HEADER_REJ;\n end if;\n end if;\nexception\nwhen INVALID_HEADER_REJ =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE MESSAGE_INFO =>\n (INVALID HEADER REJ, MESSAGE ID));\n --> TERRY PROCESSING ON THIS MESSAGE\n if CHANNE. MODE = [1] then\n CALL GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n end if;\nend CHECK_RECORD_COUNT;\nEOT..\nprocedure CHECK_RIS is\nbegin\n loop\n -> FIND NEXT RI\n if A DELIMITER OTHER THAN ['B'|CR|LF] is FOUND then\n raise INVALID_RI_FIELD;\n end if;\n exit when END_OF_ROUTING is FOUND;\n -- END_OF_ROUTING IS '.' FOR JANAP-128\n -- AND CR CR LF Z OR CR CR LF D FOR ACP-127\n if RI(1..4) not in LETTER then\n raise INVALID_RI_FIELD;\n end if;\n if RI(1..4) = OUR_RI then\n -> CHECK ENTIRE RI FOR VALIDITY\n elsif RI(3..4) = \"CR\" then\n -> CHECK RI FOR VALID COLLECTIVE RI\n else\n -> CHECK RI(1..) FOR VALID RELAY RI\n end if;\n if RI GOOD then\n -> ADD RI TO VALID_RI_LIST\n else\n -> ADD RI TO INVALID_RI_LIST\n end if;\n end loop;\n if VALID_RI_LIST is EMPTY then\n raise ALL_RI_INVALID;\n elsif INVALID_RI_LIST not EMPTY then\n raise INVALID_RI;\n end if;\n if ACP-127 and END_OF_ROUTING = CR CR LF Z then\n ---> RETURN TO CHECK_127_HEADER (THIS LINE WAS A PILOT)\n end if;\nexception\n when INVALID_RI_FIELD =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID_RI_FIELD,MESSAGE_ID));\n ---> TERMINATE MESSAGE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n when ALL_RI_INVALID =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (ALL_RI_INVALID,MESSAGE_ID,INVALID_RI_LIST));\n ---> TERMINATE MESSAGE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n when INVALID_RI =>\nCALL GENERATE SERVICE MESSAGE(SERVICE_MESSAGE_INFO =>\n(INVALID_RI,MESSAGE_ID,INVALID_RI_LIST));\nif PRECEDENCE = ['W'..'Y'..'Z'] then\n CIC_CA1(4) := 'W';\nend if;\nend CHECK_RIS;\n\nEOT...\nprocedure CHECK_EOM is\nbegin\n if OSSN /= EOM VALIDATION(2..5) then\n -- USE ACP_SSN FOR ACP-127\n CALL GENERATE SERVICE MESSAGE(SERVICE MESSAGE INFO =>\n (SUSPECTED STRAGGLER, MESSAGE_ID));\n if PRECEDENCE = [W;Y;Z] then\n CIC_CA(4) := 'W';\n else\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT MESSAGE, MESSAGE_ID);\n end if;\n end if;\n elsif EOM SEQ DOES not CONTAIN LF & \"NNNN\" then\n CALL GENERATE SERVICE MESSAGE (SERVICE MESSAGE INFO =>\n (INVALID EOM REJ, MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT MESSAGE, MESSAGE_ID);\n end if;\n end if;\n if PRECEDENCE = ['W';'Y';'Z'] then\n CALL GENERATE SERVICE MESSAGE(SERVICE MESSAGE INFO =>\n (HIGH PRECEDENCE ACCEPTANCE, MESSAGE ID));\n end if;\n if CHANNEL MODE = 5 then\n ECSN := ECSN + 1;\n end if;\nend CHECK_EOM;\n\nEOT..\nprocedure CHECK_EOT is\nbegin\n if not SINGLE_CARD then\n if EOT_CARD_OSSN /= ACP SSN then\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (SUSPECTED_STRAGGLER, MESSAGE_ID));\n if PRECEDENCE = [X|Y|Z] then\n CIC_CAI(4) := 'W';\n else\n -- TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID)\n end if;\n end if;\n end if;\n end if;\n\n if JANAP_FMT_LN 2.RECORD_COUNT = \"PLTS\" then\n if EOT_CARD.RECORD_COUNT < 3 or EOT_CARD.RECORD_COUNT >\n 500 then\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_YOM_REJ, MESSAGE_ID));\n -- TERMINATE PROCESSING ON THIS MESSAGE;\n if CHANNEL MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID)\n end if;\n end if;\n end if;\n\n elsif JANAP_FMT_LN 2.RECORD_COUNT = \"MTMS\" then\n if EOT_CARD.RECORD_COUNT /= ACTUAL_RECORD_COUNT then\n -- THIS IMPLIES YOU MUST COUNT THE ACTUAL NUMBER OF\n -- RECORDS\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_EOM_REJ, MESSAGE_ID));\n -- TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID)\n end if;\n end if;\n end if;\n\n else\n if EOT_CARD.RECORD_COUNT /= ACTUAL_RECORD_COUNT then\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_EOM_REJ, MESSAGE_ID));\n -- TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID)\n end if;\n end if;\n end if;\nend if;\nelse\n if SINGLE_CARD(80) /= 'N' then\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_EOM_REJ, MESSAGE_ID));\n -- TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1:3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n end if;\n end if;\nend if;\nif PRECEDENCE = ['W','Y','Z'] then\n CALL GENERATE_SERVICE_MESSAGE (SERVICE_MESSAGE_INFO =>\n (HIGH_PRECEDENCE_ACCEPTANCE, MESSAGE_ID));\nend if;\nif CHANNEL_MODE := 5 then\n ECSN := ECSN + 1;\nend if;\ned CHECK_EOT;\n\nEOT..\nprocedure CHECK_HP_127_HEADER is\nbegin\n if BELL SIGNAL (or GARBLED BELL SIGNAL) is PRESENT then\n --> SEARCH FIRST 18 CHARACTERS FOR 'b'\n if not FOUND then\n CALL GENERATE SERVICE MESSAGE(SERVICE MESSAGE_INFO =>\n (INVALID HEADER REJ, MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n end if;\n elsif ACP_FMT_LN 2(3) /= 'b' then\n CALL GENERATE SERVICE MESSAGE(SERVICE MESSAGE_INFO =>\n (INVALID HEADER REJ, MESSAGE_ID));\n --> TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1;3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n end if;\nend CHECK_HP_127_HEADER;\nEOT.\nprocedure CHECK_RIS is\nbegin\n loop\n --> FIND NEXT RI\n if A DELIMITER OTHER THAN ['B'|CR|LF] is FOUND then\n raise INVALID_RI_FIELD;\n end if;\n exit when END_OF_ROUTING is FOUND;\n -- END_OF_ROUTING IS '.' FOR JANAP-128\n -- AND CR CR LF Z OR CR CR LF D FOR ACP-127\n if RI(1..4) not in LETTER then\n raise INVALID_RI_FIELD;\n end if;\n if RI(1..4) = OUR RI then\n --> CHECK ENTRÉ RI FOR VALIDITY\n elsif RI(3..4) = \"CR\" then\n --> CHECK RI FOR VALID COLLECTIVE RI\n else\n --> CHECK RI(1..) FOR VALID RELAY RI\n end if;\n if RI GOOD then\n --> ADD RI TO VALID_RI_LIST\n else\n --> ADD RI TO INVALID_RI_LIST\n end if;\n end loop;\n if VALID_RI_LIST is EMPTY then\n raise ALL_RI_INVALID;\n elsif INVALID_RI_LIST not EMPTY then\n raise INVALID_RI;\n end if;\n if ACP-127 and END_OF_ROUTING = CR CR LF Z then\n --> RETURN TO CHECK_127_HEADER (THIS LINE WAS A PILOT)\n end if;\n exception\n when INVALID_RI_FIELD =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n INVALID_RI_FIELD,MESSAGE_ID));\n --> TERMINATE MESSAGE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n when ALL_RI_INVALID =>\n CALL GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n ALL_RI_INVALID,MESSAGE_ID,INVALID_RI_LIST));\n --> TERMINATE MESSAGE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n when INVALID_RI =>\nCALL GENERATE SERVICE MESSAGE(SERVICE_MESSAGE_INFO => (INVALID_RI, MESSAGE_ID, INVALID_RI_LIST));\nif PRECEDENCE = ['W', 'Y', 'Z'] then\n CJC_CA(4) := 'W';\nend if;\nend CHECK_RIS;\n\nEOT.\nprocedure COMPLETE_HP_127_HEADER is\nbegin\n if ACP_SSN PRECEDED BY '#' then\n -- > RETAIN FOR STRAGGLER CHECK\n end if;\n -- > MAKE 3 OF 5 CHECK ON CLASS X5\n -- > 3 OUT OF THE 5 CLASS CHARACTERS MUST BE CORRECT AND AGREE\n -- > TO ESTABLISH THE CLASSIFICATION OF THE MESSAGE\n -- > IF THIS CHECK FAILS, GENERATE AN INVALID SCTY_FIELD'SVC\n -- > MESSAGE, TERMINATE AND REJECT THE MESSAGE\n if (CLASS = 'U' and OP_SIGNAL /= \"ZNR\") or (CLASS /= 'U' and\n OP_SIGNAL /= \"ZNY\") then\n CALL_GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (INVALID SCTY FIELD, MESSAGE_ID));\n -- > TERMINATE PROCESSING ON THIS MESSAGE\n end if;\n if CHANNEL_MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE, MESSAGE_ID);\n end if;\n if CLASS >= LINE DATA SECURITY PROSIGN then\n GENERATE_CONTROL_CHARACTER(REJECT MESSAGE, MESSAGE_ID);\n GENERATE_SERVICE_MESSAGE(SERVICE_MESSAGE_INFO =>\n (SCTY MISMATCH, MESSAGE_ID));\n -- > TERMINATE PROCESSING ON THIS MESSAGE\n end if;\nend COMPLETE_HP_127_HEADER;\n\nEOT..\nprocedure CHECK_EOM is\nbegin\n if OSSN /= EOM VALIDATION(2..5) then\n -- USE ACP_SSN FOR ACP-127\n CALL GENERATE SERVICE MESSAGE(SERVICE_MESSAGE_INFO =>\n (SUSPECTED_STRAGGLER, MESSAGE_ID));\n if PRECEDENCE = [W|Y|Z] then\n CIC_CAI(4) := 'W';\n else\n -- TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n end if;\n end if;\nelsif EOM_SEQ DOES not CONTAIN LF & \"NNNN\" then\n CALL GENERATE SERVICE MESSAGE (SERVICE_MESSAGE_INFO =>\n (INVALID_EOM_REJ,MESSAGE_ID));\n -- TERMINATE PROCESSING ON THIS MESSAGE\n if CHANNEL_MODE = [1|3] then\n GENERATE_CONTROL_CHARACTER(REJECT_MESSAGE,MESSAGE_ID);\n end if;\n if PRECEDENCE = ['W'|'Y'|'Z'] then\n CALL GENERATE_SERVICE MESSAGE(SERVICE_MESSAGE_INFO =>\n (HIGH_PRECEDENCE_ACCEPTANCE,MESSAGE_ID));\n end if;\n if CHANNEL_MODE = 5 then\n ECSN := ECSN + 1;\n end if;\nend CHECK_EOM;\n\nEOT..\nprocedure CHECK_FOR_MCB is\nbegin\n if MCB_RECEIVED then\n MODIFY_MCB;\n elsif JANAP_128 then\n BUILD_JANAP_MCB;\n else\n BUILD_ACP_MCB;\n end if;\nend CHECK_FOR_MCB;\n\nEOT..\nprocedure BUILD_JANAP_MCB is\nbegin\n LMFPAIR := LMFPAIR (FROM HEADER);\n CICCAI := CICCAI (FROM HEADER);\n OSRI := OSRI (FROM HEADER);\n OSSN := OSSN (FROM HEADER);\n DATETIME := DATETIME (FROM HEADER);\n if MODE = 2 or MODE = 4 or MODE = 5 then\n --> ADD ICD\n --> ADD ICSN\n else\n ICD := 'bbb';\n ICSN := 'bbbb';\n end if;\nend BUILD_JANAP_MCB;\n\nEOT..\nprocedure BUILD_ACP_MCB is\nbegin\n LMF_PAIR := FT;\n CIC_CAIR := ZYUW;\n OSRI := HOME_RELAY (?) & ICD;\n OSSN := '0' & ICSN;\n DATE_TIME := SOM_IN_DATE_TIME;\n ICD := 'bbb';\n ICSN := 'bbbb';\nend BUILD_ACP_MCB;\n\nEOT..\nprocedure MODIFY_MCB is\n type CT is 0..2;\n COUNT : CT;\nbegin\n COUNT := 0;\n for all CHARACTERS in TDW loop\n if CHARACTER = SWITCH_ID then\n COUNT := COUNT + 1;\n end if;\n end loop;\ncase COUNT is\n when 0 =>\n -- ADD SWITCH_ID TO FIRST ZERO FIELD\n when 1 =>\n -- ZERO ALL FIELDS AFTER POSITION OF SWITCH_ID\n -- ADD SWITCH_ID SECOND TIME\n when 2 =>\n -- HOLD MESSAGE\n -- NOTIFY OPERATOR (PROVIDE ORBIT INFORMATION)\nend case;\nBP := MAC(1);\nfor I in 2..83 loop\n BP := BP xor MCB(I);\nend loop;\n-- ADD SOH_TIME\nend MODIFY_MCB;\nprocedure COMPLETE_MCB is\n begin\n -- PICK SELECT CHARACTER BASED ON LMF\n PRECEDENCE := PRECEDENCE (FROM HEADER);\n CLASS := CLASS (FROM HEADER);\n NUMBER_BLOCKS := NUMBER of BLOCKS RECEIVED;\n -- ADD SOH TIME\n if COLLECTIVE RIS in HEADER then\n TRIP = 'C';\n else\n TRIP = 'N';\n end if;\n if SERVICE MESSAGE then\n SDC := 'S';\n elsif PRECEDENCE = W then\n -- CRITIC\n if COLLECTIVE RIS in HEADER then\n if MESSAGE COMPLETE then\n SDC := 'M';\n else\n SDC := 'I';\n end if;\n else\n -- NO COLLECTIVE RIS\n if MESSAGE COMPLETE then\n SDC := 'C';\n else\n SDC := 'P';\n end if;\n end if;\n else\n SDC := 'b';\n end if;\n TDW := (1..12 => 0);\n OASC := SWITCH_ID;\n if SERVICE MESSAGE then\n SMRI := RI(2..6) (FROM HEADER);\n else\n SMRI := 'bbbbbb';\n end if;\n SDO := 'b';\n TASC := 'b';\n SASC := 'b';\n BP := MCB(1);\n for I in 2..83 loop\n BP := BP xor MCB(I);\n end loop;\n end COMPLETE_MCB;\nprocedure GENERATE_SERVICE_MESSAGE is\nbegin\n OBTAIN SVC MESSAGE FORMAT BASED ON SERVICE_MESSAGE_TYPE AND MESSAGE FORMAT\n FILL IN OSRI, OSSN, DATE_TIME\n ADD RI FROM ORIG MESSAGE OSRI\n ADD ORIG MESSAGE OSRI, OSSN, DATE_TIME AS REFERENCE\n if SERVICE_MESSAGE_TYPE = [INVALID_RI|OUTPUT_SCTY_MISMATCH |ILLEGAL_EXCHANGE| ALL RI INVALID] then\n ADD RIs\n elsif SERVICE_MESSAGE_TYPE = OPEN_CSN or INCORRECT_CSN then\n ADD CSNS\n end if;\nend GENERATE_SERVICE_MESSAGE;\n\nEOT..\nprocedure ROUTE_TO_STORAGE is\nbegin\n -- SEND A COPY OF THE MESSAGE & MCB TO REFERENCE STORAGE\n if PRECEDENCE /= W and PRECEDENCE /= Y and PRECEDENCE /= Z\n and THRESHOLD_STATUS = UPPER then\n -- ROUTE MESSAGE AND MCB TO OVERFLOW\n -- MAKE AN OVERFLOW_OUT_ENTRY\n else\n -- ROUTE MESSAGE TO INTRANSIT STORAGE\n end if;\nend ROUTE_TO_STORAGE;\n\nEOT..\nprocedure DETERMINE_SATURATION_LEVEL is\nbegin\n if OCCUPANCY_LEVEL > UPPER_THRESHOLD then\n THRESHOLD_STATUS = UPPER;\n elsif OCCUPANCY_LEVEL > MIDDLE_THRESHOLD then\n THRESHOLD_STATUS = UPPER_MIDDLE;\n elsif OCCUPANCY_LEVEL > LOWER_THRESHOLD then\n THRESHOLD_STATUS = LOWER_MIDDLE;\n else\n THRESHOLD_STATUS = LOW;\n end if;\nend DETERMINE_SATURATION_LEVEL;\n\nEOT..\nprocedure REENTER_FROM_OVERFLOW is\nbegin\n loop\n if THRESHOLD_STATUS = LOW then\n for all MESSAGES in OVERFLOW_STORAGE loop\n --> ROUTE MESSAGE TO INTRANSIT_STORAGE\n --> MAKE OVERFLOW_IN_ENTRY\n end loop;\n end if;\n end loop;\nend REENTER_FROM_OVERFLOW;\n\nEOT..\nprocedure SELECT_NEXT_MESSAGE is\nbegin\n -- > WITHIN THE HIGHEST PRIORITY MESSAGES AVAILABLE\n -- > SELECT THE EARLIEST SERVICE MESSAGE\n if NO SERVICE MESSAGES then\n -- > SELECT THE EARLIEST MESSAGE\n end if;\n end SELECT_NEXT_MESSAGE;\n\nEOT..\nprocedure EXPAND_COLLECTIVE_RIS is\nbegin\nfor all RIS in HEADER loop\n if RI(3..4) = \"CR\" then\n --> LOOK UP in COLLECTIVE RI TABLE\n --> ASSOCIATE RI WITH LINE ON LINES FOR OUTPUT\n end if;\nend loop;\nend EXPAND_COLLECTIVE_RIS;\nEOT..\nprocedure LOOK_UP_INDIVIDUAL_RIS is\nbegin\n for all RIS ON ROUTING LINE loop\n if RI(3..4) /= \"CR\" then\n --> LOOK UP RI IN ROUTING TABLE\n --> ASSOCIATE LINE FOR OUTPUT WITH RI\n end if;\n end loop;\nend LOOK_UP_INDIVIDUAL_RIS;\nEOT..\nprocedure SEGREGATE is\nbegin\n for NEXT RI in ROUTE.LINE loop\n if NEXT RI = RI TERMINATOR (2EH) then\n copy RI TERMINATOR TO NEW_ROUTE_LINE;\n exit loop;\n end if;\n if NEXT RI = RI in GROUP RI then\n copy NEXT RI TO NEWROUTE_LINE;\n else\n repeat until all RI in GROUP RI have been compared to\n NEXT RI;\n end if;\n if NO RI = NEXT RI then\n if OUTPUT DEVICE is DTE then\n if LMF PAIR = \"SC\", \"CC\", \"BB\", \"DD\" or \"II\"then\n copy an equivalent number of spaces to\n NEW_ROUTE_LINE;\n end if;\n elsif LMF FIRST = \"S\", \"C\", \"B\", \"D\" or \"I\"then\n copy a single space to NEW ROUTE LINE;\n elsif LMF FIRST = \"T\", \"R\", \"F\", \"Q\" or \"A\"then\n copy \"SI\"(OFH) to NEW_ROUTE_LINE;\n else\n raise LMF_ERROR;\n end if;\n end if;\n end if;\n end loop;\nend SEGREGATE;\n\nEOT.\nprocedure CHECK_LMFPAIR is\nbegin\n if SECOND_LMF_CHARACTER not ACCEPTABLE TO LINE then\n TRANSLATION_PAIR = FIRST_LMF_CHARACTER & LINE_LMF_CHARACTER;\n else\n TRANSLATION_PAIR = LMF_PAIR;\n end if;\n if TRANSLATION_PAIR /= LEGAL_EXCHANGE then\n -- > REMOVE MESSAGE FROM SYSTEM\n -- > TREAT RI AS BAD RI\n -- > GENERATE SERVICE MESSAGE\n -- > INFORM OPERATOR\n end if;\nend CHECK_LMFPAIR;\n\nEOT..\nprocedure CHECK_FORMAT_TRANSLATION is\nbegin\n -- READ FORMAT_INFO_FILE (KEY => TRANSLATION_PAIR)\n if TO 127 then\n CONVERT_TO_ACP_127;\n elsif TO T28 then\n CONVERT_TO_JANAP_128;\n else\n null;\n end if;\nend CHECK_FORMAT_TRANSLATION;\n\nEOT.\nprocedure CONVERT_TO_JANAP_128 is\nbegin\n --> DELETE ACP_FMT_LN 2, SAVING INFO\n --> GENERATE JANAP_FMT_LN 2 AS FOLLOWS\n PRECEDENCE := PRECEDENCE FROM FMT_LN 2;\n LMF_PAIR := \"FT\";\n CLASS := CLASS FROM FMT_LN 4;\n CIC_CAI = ?????????;\n if ORIGINATING_STATION is RELAY or TRIBUTARY OFF S&F then\n OSRI(1..4) := RELAY_RI(1..4);\n else\n OSRI(1..4) := S&F_RI(1..4);\n end if;\n OSRI(5..7) := CHANNEL ID;\n OSSN(5..7) := '0' & INCOMING CSN;\n DATE_TIME := DATE_TIME-RECEIVED;\n RIS := ACP_RIS;\n --> ADD SPACES, DASHES AND END OF ROUTING INDICATOR AS REQUIRED\nend CONVERT_TO_JANAP_128;\n\nEOT..\nprocedure CONVERT_TO_ACP_127 is\nbegin\n if FMT_LINE 4 is CORRECT or MESSAGE is SUSP_DUP then\n --> DELETE JANAP_FMT_LN_2, SAVING INFO\n -- GENERATE ACP_FMT_LN_2 AS FOLLOWS\n DOUBLE_PRECEDENCE_PROSIGN := (1,2 => PRECEDENCE);\n --> COPY RIS_Form_JANAP_FMT_LN_2\n -- GENERATE ACP_FMT_LN_3 AS FOLLOWS\n PROSIGN := \"DE\";\n RI := OSRI;\n ACP_SSN := OSSN;\n DATE_TIME := DATE_TIME;\n if PRECEDENCE = 'Y' or PRECEDENCE = 'Y' then\n --> INSERT <FIGS JJJJJSSSSS LTRS> BEFORE FMT_LN 2\n end if;\n if FMT_LN 4 not CORRECT then\n -- GENERATE FMT_LN 4 (ONLY ON SUSP DUP)\n if CLASS = 'U' then\n OP_SIGNAL := \"ZNR\";\n else\n OP_SIGNAL := \"ZNY\";\n end if;\n CLASS_X5 := (1,2,3,4,5 => CLASS);\n end if;\n --> ADD 12 LTRS AFTER EOM SEQUENCE\nelse\n --> REMOVE MESSAGE FROM SYSTEM\n --> INFORM SUPERVISOR\n --> GENERATE INVALID_RI SERVICE MESSAGE\n end if;\nend CONVERT_TO_ACP_127;\n\nEOT..\nprocedure CHECK_FOR_DELETE_REMOVAL is\nbegin\n -- READ DELETE_INFO_FILE (KEY => TRANSLATION_PAIR)\n if YES then\n REMOVE_DELETES;\n end if;\nend CHECK_FOR_DELETE_REMOVAL;\n\nEOT..\nprocedure REMOVE_DELETES is\nbegin\nfor all CHARACTERS in BODY loop\n if CHARACTER = SI or CHARACTER = SO then\n --> PLACE ' ' IN NEW_BODY\n elsif CHARACTER /= DEL then\n --> PLACE CHARACTER IN NEW_BODY\n end if;\nend loop;\nBODY := NEW_BODY;\nend REMOVE_DELETES;\nEOT..\nprocedure CHECK_FOR_CHARACTER_SET_TRANSLATION is\nbegin\n --> READ CHAR_SET_INFO_FILE (KEY => TRANSLATION_PAIR)\n if ASCII then\n TRANSLATE TO ASCII;\n elsif ITA then\n TRANSLATE TO ITA_2;\n else\n null;\n end if;\nend CHECK_FOR_CHARACTER_SET_TRANSLATION;\n\nEOT..\nprocedure TRANSLATE_TO_ASCII is\nbegin\n CURRENT_CASE := LTRS;\n for all CHARACTERS in MESSAGE loop\n if CHARACTER = LTRS or CHARACTER = FIGS then\n CURRENT_CASE := CHARACTER;\n end if;\n end loop;\nend TRANSLATE_TO_ASCII;\n\nEOT..\nprocedure TRANSLATE_TO_ITA_2 is\nbegin\n --> INSERT LTRS IN NEW_MESSAGE\n CURRENT_SHIFT := LTRS;\n for all_CHARACTERS in MESSAGE loop\n --> LOOK UP ITA_EQUIV AND REQUIRED_SHIFT FOR\n -- CHARACTER\n if REQUIRED_SHIFT /= CURRENT_SHIFT then\n --> INSERT REQUIRED_SHIFT\n CURRENT_SHIFT := REQUIRED_SHIFT;\n end if;\n --> INSERT ITA_EQUIV IN NEW_MESSAGE;\n end loop;\n MESSAGE := NEW_MESSAGE;\nend TRANSLATE_TO_ITA_2;\n\nEOT.\nprocedure CHECK_FOR_CARD_CONVERSION is\nbegin\n --> READ CARD_INFO_FILE ( KEY => TRANSLATION_PAIR)\n if TO CARD then\n TRANSLATE TO CARD;\n elsif FROM CARD then\n TRANSLATE_FROM_CARD;\n else\n null;\n end if;\nend CHECK_FOR_CARD_CONVERSION;\n\nEOT..\nprocedure TRANSLATE_TO_CARD is\nbegin\n -- PLACE \"MTMS\" IN RECORD_COUNT OF HEADER\n for all LINES in BODY loop\n -- A LINE IS THE SEQUENCE OF CHARACTERS BETWEEN CR-CR-LF\n -- SEQUENCES\n -- DETERMINE LINE LENGTH\n if LINE_LENGTH = 80 then\n OUT_LINE := LINE;\n elsif LINE_LENGTH < 80 then\n OUTLINE := (1..LINE_LENGTH => LINE, others => ' ');\n else\n -- LINE_LENGTH > 80\n OUT_LINE := LINE(1..80);\n SECOND_OUT_LINE := (1..LINE_LENGTH-80 => LINE(81..\n LINE_LENGTH), others => ' ');\n end if;\n end loop;\n -- DELETE EOM SEQUENCE\n -- GENERATE EOT CARD WITH \"MTMS\" IN RECORD_COUNT\nend TRANSLATE_TO_CARD;\n\nEOT..\nprocedure TRANSLATE_FROM_CARD is\nbegin\n if JANAP 128 then\n for EACH LINE (CARD) in body loop\n --> DELETE TRAILING SPACES\n --> ADD CR CR LF\n end loop;\n else\n for EACH LINE in body loop\n --> COUNT PRINTABLE CHARACTERS IN LINE\n if > 69 then\n --> BREAK INTO TWO LINES OF MAX 69 CHARACTERS\n --> BREAK AT WORD AS CLOSE TO 69 CHARACTERS AS POSSIBLE\n end if;\n --> ADD CR CR LF TO EACH LINE PRODUCED\n end loop;\n end if;\n --> DELETE EOT CARD\n --> ADD EOM_SEQUENCE\nend TRANSLATE_FROM_CARD;\n\nEOT..\nprocedure CHECK_FOR_FILL is\nbegin\n --> READ FILL_INFO_FILE (KEY => TRANSLATION_PAIR)\n if YES then\n FILL_LAST_BLOCK;\n end if;\nend CHECK_FOR_FILL;\n\nEOT..\nprocedure FILL_LAST_BLOCK is\nbegin\n -- FILL LAST 80 CHARACTER BLOCK OF MESSAGE (AFTER LAST 'N')\n if ASCII then\n -- FILL WITH SI\n else\n -- FILL WITH LTRS\n end if;\nend FILL_LAST_BLOCK;\n\nEOT.\nprocedure CHECK_LINE_AVAILABILITY is\nbegin\n --> LOOK UP LINE AVAILABILITY IN LINE TABLE\n if LINE AVAILABLE then\n --> PLACE MESSAGE IS INTRANSIT_STORAGE\n else\n --> MAKE SOM ENTRY IN JOURNAL\n --> PLACE MESSAGE ON INTERCEPT_STORAGE\n --> MAKE EOM ENTRY IN JOURNAL\n if VOLUME FULL then\n --> REQUEST NEW VOLUME\n --> ENTER NEW VOLUME IN INTERCEPT_VOLUMES LIST\n end if;\n end if;\nend CHECK_LINE_AVAILABILITY;\nEOT..\nprocedure REINTRODUCE_INTERCEPTED_MESSAGES is\nbegin\n -- DONE ON SSF COMMAND\n for all VOLUMES ON INTERCEPT_VOLUMES_LIST loop\n if VOLUME NOT MOUNTED then\n --> REQUEST MOUNT BY OPERATOR\n end if;\n for all MESSAGES ON VOLUME loop\n if MESSAGE OUTPUT LINE = LINE(S) TO BE REINTRODUCED then\n --> MAKE SOM ENTRY ON JOURNAL\n --> PLACE MESSAGE IN INTRANSIT_STORAGE\n --> MAKE EOM ENTRY ON JOURNAL\n end if;\n end loop;\nend loop;\nend REINTRODUCE_INTERCEPTED_MESSAGES;\nEOT..\nprocedure SELECT_MESSAGE_FOR_OUTPUT is\nbegin\n ~> SELECT NEXT MESSAGE FOR OUTPUT BASED ON HIGHEST PRIORITY\n ~> WITHIN PRIORITY, SELECT ON EARLIEST TIME RECEIVED\nend SELECT_MESSAGE_FOR_OUTPUT;\n\nEOT..\nprocedure VALIDATE MESSAGE_LENGTH is\nbegin\n COMPUTED_NUMBER_OF_BLOCKS := 0;\n while FILE_STATUS /= END_OF_MESSAGE loop\n -- BUMP TO NEXT BLOCK(FILE_STATUS);\n COMPUTED_NUMBER_OF_BLOCKS := COMPUTED_NUMBER_OF_BLOCKS + 1;\n end loop;\n if COMPUTED_NUMBER_OF_BLOCKS /= NUMBER_BLOCKS\n then\n ERROR_CODE := INVALID_LENGTH_CODE;\n end if;\nend;\n\nEOT..\nprocedure VALIDATE_OUTPUT_RI is\nbegin\n --> DETERMINE RI THIS LINE\n --> DETERMINE RI OF CURRENT TRANSMISSION\n if RI THIS OUTPUT LINE /= RI THIS MESSAGE then\n ERROR_CODE := INVALID_LINE_RI;\n end if;\nend;\nprocedure VALIDATE_LMF is\nbegin\n case FIRST_LMF_CHARACTER is\n when B =>\n if SECOND_LMF_CHARACTER /= 'B' then\n ERROR_CODE := INVALID_LMF;\n end if;\n when J =>\n if SECOND_LMF_CHARACTER /= 'D' then\n ERROR_CODE := INVALID_LMF;\n end if;\n when I =>\n if SECOND_LMF_CHARACTER /= 'I' then\n ERROR_CODE := INVALID_LMF;\n end if;\n when S =>\n case SECOND_LMF_CHARACTER is\n when C:A:T => null;\n when others =>\n ERROR_CODE := INVALID_LMF;\n end case;\n when C:A:T:Q:F =>\n case SECOND_LMF_CHARACTER is\n when C:A:T:T_PAREN => null;\n when others =>\n ERROR_CODE := INVALID_LMF;\n end case;\n when R =>\n case SECOND_LMF_CHARACTER is\n when T:T_PAREN => null;\n when others =>\n ERROR_CODE := INVALID_LMF;\n end case;\n when others =>\n ERROR_CODE := INVALID_LMF;\n end case;\n end case;\n end case;\nend;\nprocedure VALIDATE_HEADER_SECURITY is\nbegin\n NUMBER_OF_TRANSMISSIONS := 0;\n NUMBER_OF DESTINATIONS := NUMBER_RIS_THIS_MESSAGE;\n while NUMBER_OF DESTINATIONS > 0 loop\n --> DETERMINE SECURITY OF CURRENT RI\n if CLASS > SECURITY_OF_CURRENT_RI then\n --> SAVE BAD RI\n --> DO NOT SEND TO THIS RI\n ERROR_CODE := INVALID_RI_SECURITY;\n else\n NUMBER_OF_TRANSMISSIONS := NUMBER_OF_TRANSMISSIONS + 1;\n end if;\n end loop;\n end loop;\n --> DETERMINE IF ANY RI'S WERE MISSED\n if NUMBER_OF_TRANSMISSIONS /= NO OF DESTINATIONS then\n --> PRODUCE NON-TRANSMITTED RI'S ON SERVICE MESSAGE\n GENERATE_SERVICE_MESSAGE;\n end if;\nend;\n\nEOT..\nprocedure INSERTS_OUTPUT_CHANNEL_ID_AND_NUMBER is\nbegin\n case CHANNEL_MODE is\n when 2415 =>\n --> APPEND SOH ON HEADER\n --> INSERT CHANNEL ID IN TRANSMISSION IDENTIFIER\n --> INSERT CHANNEL SEQUENCE IN TRANSMISSION IDENTIFIER\n if PRECEDENCE = 'Y' or 'Z' and\n MESSAGE_MODE = JANAP_128 then\n --> INSERT BELL CODE AFTER TRANSMISSION IDENTIFIER\n end if;\n when others =>\n null;\n end case;\n if MESSAGE CANCELLED then\n if MESSAGE_IN_TRANSMISSION then\n --> TRANSMIT CANCEL_SEQUENCE\n --> INCREMENT_CSN\n end if;\n end if;\nend;\n\nEOT..\nTHE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS FOR THE FRAMING OF ASYNCHRONOUS MESSAGES AS DESCRIBED IN THE FOLLOWING:\n\nMANUAL JANAP 128\n\n01/28/82\n\nprocedure FRAMEASYNCHRONOUSMESSAGE is\nbegin\n if MESSAGE_MODE = ACP 127 ; ACP 127 MOD then\n --> PRECEDE TEXT WITH SIX \"BLANKS\" AND SIX \"LTRS\"\n elsif MESSAGE_MODE = JANAP 128 then\n --> PRECEDE TEXT WITH SIX \"NULLS\" AND SIX \"DELETES\"\n end if;\n --> FOLLOW TEXT WITH ?????????\nend FRAMEASYNCHRONOUSMESSAGE;\n\nEOT..\nprocedure FRAME_TRIBUTARY_MESSAGE_BLOCK_BY_BLOCK is\nbegin\n case SECOND LMF CHARACTER is\n when C|R|T|A|Q =>\n if BLOCK FRAMED = 1 then\n COPY MCB TO OUTPUT BUFFER\n elsif BLOCK_FRAMED /= NUMBER BLOCKS then\n PRECEDE CURRENT BLOCK WITH \"STX\" AND \"DEL\"\n AND APPEND IT WITH \"ETB\" AND \"BP\"\n end if;\n if BLOCK_FRAMED = NUMBER BLOCKS then\n PRECEDE BLOCK WITH \"STX\" AND \"DEL\"\n APPEND \"ETX\" AND \"BP\" TO BLOCK\n end if;\n when S =>\n PRECEDE BLOCK WITH \"SOH\" AND \"D\"\n APPEND \"ETX\" AND \"BP\" TO BLOCK\n when D =>\n THE DCAC 370-D175-1 DOCUMENT REFERENCES\n TO NON-EXISTENT\n FIGURE 8-1 IN DEFINING THE FORMAT FOR LMF \"D\"\n when B|I =>\n if BLOCK_FRAMED = 1 then\n PRECEDE THE MCB WITH \"SOH\" AND \"D\" CHARACTERS\n FOLLOW IT WITH \"ETX\" AND \"BP\" CHARACTERS\n elsif BLOCK_FRAMED = 2|NUMBER BLOCKS then\n BUILD MODE CHANGE BLOCK\n TRANSMIT MODE CHANGE BLOCK\n else\n PRECEDE MESSAGE BLOCK WITH \"SOH\" AND \"D\"\n CHARACTERS\n AND FOLLOW IT WITH ?????????????????\n end if;\n when G =>\n if BLOCK_FRAMED=1 then\n PRECEDE BLOCK OF MESSAGE WITH \"SOH\" AND SEL\n CHARACTERS\n AND FOLLOW IT WITH \"EM\", \"ETB\", AND \"BP\" CHARACTERS\n elsif BLOCK_FRAMED /= NUMBER BLOCKS then\n PRECEDE BLOCK WITH \"STX\" AND \"DEL\" CHARACTERS\n AND FOLLOW IT WITH \"ETB\" AND \"BP\" CHARACTERS\n elsif BLOCK_FRAMED = NUMBER BLOCKS then\n PRECEDE BLOCK WITH \"STX\" AND \"DEL\" CHARACTERS\n AND FOLLOW IT WITH \"ETB\" AND \"BP\" CHARACTERS\n end if;\nend case;\n\nwhen others =>\n ERROR_CODE := INVALID_LMF;\nend case;\nend FRAME_TRIBUTARY_MESSAGE_BLOCK_BY_BLOCK;\nEOT..\nprocedure FRAME_TRUNK_MESSAGE_BLOCK_BY_BLOCK is\nbegin\n case SECOND_LMF_CHARACTER is\n when C|R|T|A|Q =>\n if BLOCK_COUNT = 1 then\n --> PRECEDE HEADER WITH \"SOH\" AND \"BP\"\n --> FOLLOW HEADER WITH \"ETB\" AND \"BP\"\n elsif BLOCK_COUNT /= NUMBER_BLOCKS then\n --> PRECEDE BLOCK WITH \"STX\" AND \"SEC\" CHARACTERS\n --> FOLLOW IT WITH \"ETB\" AND \"BP\" CHARACTERS\n elsif BLOCK_COUNT = NUMBER_BLOCKS then\n --> PRECEDE BLOCK WITH \"STX\"\n --> FOLLOW BLOCK WITH \"ETX\" AND \"BP\"\n end if;\n when S =>\n if BLOCK_COUNT = 1 then\n --> PRECEDE HEADER WITH \"SOH\" AND \"D\"\n --> FOLLOW HEADER WITH \"ETB\" AND \"EB\"\n else\n --> PRECEDE BLOCK WITH \"STX\" AND \"U\"\n --> FOLLOW BLOCK WITH \"ETX\" AND \"BP\"\n end if;\n end case;\nend FRAME_TRUNK_MESSAGE_BLOCK_BY_BLOCK;\n\nEOT..\nTHE PURPOSE OF THIS PROCEDURE IS TO DESCRIBE THE FRAMING OF SYNCHRONOUS MESSAGES WITH THE PROPER PROTOCOL AS DICTATED BY THE LMF OF THE RECEIVING STATION. THIS REQUIREMENT IS CONTAINED IN DCAC 370-D175-1, CHAPTER 8.\n\n12/11/81 RCR\n\nprocedure FRAME_SYNCHRONOUS_MESSAGE_BLOCK_BY_BLOCK is begin\n case OUTPUT_LINE_TYPE is\n when TRIBUARY =>\n FRAME_TRIBUTARY_MESSAGE_BLOCK_BY_BLOCK;\n when TRUNK =>\n FRAME_TRUNK_MESSAGE_BLOCK_BY_BLOCK;\n end case;\n -- A BLOCK OF A SYNCHRONOUS BLOCK-BY-BLOCK MESSAGE IS READY TO TRANSMIT.\n -- SYNCHRONOUS CONTINUOUS MESSAGES CANNOT BE TRANSMITTED UNTIL ALL BLOCKS ARE FRAMED.\n end FRAME_SYNCHRONOUS_MESSAGE_BLOCK_BY_BLOCK;\nEOT...\nThe purpose of this routine is to add protocol to a given message as a function of:\n\n- Synchronous/Asynchronous\n- LMF\n- Trunk/Tributary\n- Mode of transmission\n\nThis protocol is required by the following by the following manual references:\n\n- Manual Paragraph\n - TT-B1-1101-0001A 3.2.1.2.15\n - 3.2.1.2.8.6\n - DCAC 370-D175-1 Chapter 5, 8, 11\n- 12/15/81 RCR\n\nprocedure ADD_PROTOCOL is\nbegin\n case TYPE OF TRANSMISSION is\n when ASYNCHRONOUS =>\n -- The basic unit of transmission is the message.\n -- It is framed by start of messages and end of message\n -- sequences as defined in JANAP-128 and ACP-127.\n -- The asynchronous coordination is a derivative\n -- of mode I synchronous control.\n frame ASYNCHRONOUS MESSAGE;\n when SYNCHRONOUS =>\n -- The basic unit of transmission for synchronous\n -- messages is an 80 character (or less) block\n -- framed by special characters. The protocol\n -- defines unique framing for \"first\", \"intermediate\"\n -- and \"last\" blocks.\n BLOCK_FRAMED := 1;\n while BLOCKED_FRAMED <= NUMBER_BLOCKS loop\n frame SYNCHRONOUS MESSAGE BLOCK BY BLOCK;\n BLOCK_FRAMED := BLOCKED_FRAMED + 1;\n end loop;\n -- Since all blocks are framed, now\n -- ready to transmit synchronous continuous messages\n end case;\nend;\nTRANSMIT A BLOCK\nTHE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS FOR THE TRANSMISSION OF A BLOCK OF A BLOCK-BY-BLOCK SYNCHRONOUS MESSAGE AS DESCRIBED BY THE FOLLOWING:\n\nMANUAL PARAGRAPH\n\nTT-B1-1101-0001A 3.2.1.2.15\nDCAC 370-D175-1 CHAPTER 5\n\nprocedure TRANSMIT_SYNCHRONOUS_MESSAGE_BLOCK_BY_BLOCK is\nbegin\nloop\nloop\nGENERATE_CONTROL_CHARACTERS;\nif BLOCK_READY_TO_SEND then\nexit;\nelse\n--> SEND SYNC CHARACTERS\nend if;\nend loop;\nTRANSMIT_START_OF_BLOCK;\nTRANSMIT_BLOCK_TEXT;\nif SYNC_DATA_MODE /= BLOCK_BY_BLOCK then\nif ACK_RECEIVED_FOR_LAST_BLOCK /= TRUE then\nTRANSMIT_CONTROL;\nend if;\nend if;\nGENERATE_CONTROL_CHARACTERS;\nTRANSMIT_END_OF_BLOCK;\nif SYNC_DATA_MODE = BLOCK_BY_BLOCK then\nTRANSMIT_CONTROL;\nend if;\nWAIT_FOR_BLOCK_ACKNOWLEDGEMENT;\n-- START AND END OF MESSAGE JOURNAL ENTRIES MAY BE MADE AT THIS POINT\nif BLOCK_COUNT = 1 then\nOUTPUT_JOURNAL_ENTRY_TYPE := START_OF_MESSAGE_OUT_CODE;\nelsif BLOCK_COUNT = NUMBER_BLOCKS then\nOUTPUT_JOURNAL_ENTRY_TYPE := END_OF_MESSAGE_OUT_CODE;\nend if;\n--> GENERATE JOURNAL ENTRY\nend loop;\nend;\nEOT..\nprocedure TRANSMIT_START_OF_MESSAGE is\n begin\n -- THE FIRST TWO FRAMING CHARACTERS WERE INSERTED\n -- IN THE TEXT ACCORDING TO MODULE A532\n --> TRANSMIT FRAMING CHARACTERS\n end;\n\nEOT..\n-- A5412\n-- THE PURPOSE OF THIS PROCEDURE IS TO DESCRIBE THE\n-- REQUIREMENTS FOR THE TRANSMISSION OF THE TEXT PORTION\n-- OF A MESSAGE BLOCK AS CONTAINED BY THE FOLLOWING:\n-- MANUAL PARAGRAPH\n-- TT-B1-1101-0001A 3.2.1.2.15\n-- DCAC 370-D175-1 CHAPTER 5-4(d)\n-- 02/03/81 RCR\n\nprocedure TRANSMIT_BLOCK_TEXT is\nbegin\n CHARACTERS_THIS_BLOCK := 2;\n -- COUNTER INCLUDES TWO FRAMING CHARACTERS\n loop\n GENERATE_CONTROL_CHARACTERS;\n if CURRENT_CHARACTER = TEXT_CHARACTER!MODE_CONTROL;\n CHARACTERS_THIS_BLOCK := CHARACTERS_THIS_BLOCK + 1;\n -- UPDATE PARITY OF BLOCK\n -- SEND CURRENT CHARACTER\n if CHARACTERS_THIS_BLOCK = 82 or CURRENT_CHARACTER = EOM then\n exit;\n end if;\n end if;\n end loop;\nend;\nEOT.\nTHE PURPOSE OF THIS PROCEDURE IS TO DESCRIBE THE REQUIREMENTS FOR THE TRANSMISSION OF THE END-OF-BLOCK SEQUENCE AS CONTAINED IN THE FOLLOWING:\n\nMANUAL PARAGRAPH\nTT-B1-1101-0001A 3.2.1.2.15\nDCAC 370-D175-1 CHAPTER 5-4(e)\n\nprocedure TRANSMIT_END_OF_BLOCK is\nbegin\n -- SEND END-OF-BLOCK SEQUENCE\n -- SEND BLOCK PARITY\n -- SET EOMS SENT CODE\n GENERATE_CONTROL_CHARACTERS;\nend;\n-- A5414\n-- THE PURPOSE OF THIS PROCEDURE IS TO DESCRIBE THE\n-- REQUIREMENTS FOR THE RECEIPT OF ACKNOWLEDGEMENTS\n-- TECHNIQUE AS CONTAINED IN THE FOLLOWING:\n-- MANUAL PARAGRAPH\n-- TT-B1-1101-0001A 3.2.1.2.15\n-- DCAC 378-D175-1 CHAPTER 5-4(e)\n-- CHAPTER 3-4(a)\n-- 02/03/81 RCR\nprocedure WAIT_FOR_BLOCK_ACKNOWLEDGEMENT is\nbegin\n GENERATE_CONTROL_CHARACTERS;\n -- SATISFIES THE FOLLOWING REQUIREMENTS:\n -- ACK RECEIVED := FALSE;\n -- TIMER_TRYS := 0;\n -- while TIMER_TRYS <= 3 loop\n -- RESET ACK_TIMER TO MAX VALUE\n -- (A DECREASING COUNTER ASSUMED)\n -- while ACK_TIMER > 0 loop\n -- if CONTROL_CHARACTERS_TO_BE_SENT then\n -- SEND_INDICATED_CONTROLS\n -- else\n -- SEND_SYNC_CHARACTERS\n -- end if;\n -- end loop;\n -- TIMER_TRYS := TIMER_TRYS +1\n -- SEND_REPLY_CHARACTER\nend loop;\n-- TIMER HAS EXPIRED THREE TIMES\n-- ACTIVATE ALARM\nend WAIT_FOR_BLOCK_ACKNOWLEDGEMENT;\nEOT..\nTHE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS FOR SENDING A RCC, RECEIVER CONTROL CHARACTER, SEQUENCE AS DESCRIBED IN THE FOLLOWING:\n\nDCAC 370-D175-1 11-28\n\nprocedure SEND_RCC_SEQUENCE is\n begin\n GENERATE_CONTROL_CHARACTERS;\n\n THIS PROCEDURE SATISFIES THE FOLLOWING REQUIREMENTS:\n if SEND_GEN_CODE = FALSE then\n return;\n elsif STOP_CODE = TRUE then\n SEND_STOPSEQUENCE;\n elsif RT_CODE = TRUE then\n SEND_RTSEQUENCE;\n else if ACK_ALTERNATE = ACK_1 then\n SEND_ACK1_SEQUENCE;\n else\n SEND_ACK2_SEQUENCE;\n end if;\n end if;\n RCC_TO_SEND := FALSE;\n SEND_GEN_CODE := FALSE;\n end SEND_RCC_SEQUENCE;\nEOT.\n-- A5422\n-- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\n-- FOR REPLYING TO CANCEL COMMAND DESCRIBED IN THE FOLLOWING:\n-- MANUAL\n-- DCAC 370-D175-1\n-- 01/14/82 RCR\nprocedure REPLY_TO_CAN is\nbegin\n GENERATE CONTROL CHARACTERS;\n THIS PROCEDURE SATISFIES THE FOLLOWING REQUIREMENTS:\n if STOP RECD CODE = TRUE then\n STOP RECD CODE := FALSE;\n THREE_RPT COUNTER := 0;\n elsif ACK RECD CODE = TRUE then\n CAN_CODE := FALSE;\n REPLY_TIMER := 0;\n THREE_RPT COUNTER := 0;\n if CAN-SENT WITHIN MESSAGE then\n --> RETURN MESSAGE TO QUEUE\n --> PREPARE TO SEND CANTRAN\n end if;\n end if;\n if REPLY TIMER EXPIRED then\n --> RESET REPLY TIMER\n if THIRD CAN SENT W/O RESPONSE then\n TCC_TO_SEND := TRUE;\n else\n TCC_TO_SEND := TRUE;\n end if;\n else\n STOP RECD CODE := FALSE;\n THREE_RPT COUNTER := 0;\n end if;\n end if;\n STOP RECD CODE := FALSE;\n THREE_RPT COUNTER := 0;\n end REPLY_TO_CAN;\nEOT..\nprocedure REPLY_TO_REP_OR_STOP is\nbegin\n GENERATE_CONTROL_CHARACTERS;\n \\text{THIS PROCEDURE SATISFIES THE FOLLOWING REQUIREMENTS:}\n if STOP_RECD_CODE = TRUE then\n \\text{STOP\\_RECD\\_CODE} := \\text{FALSE};\n \\text{THREE\\_RPT\\_COUNTER} := 0;\n elsif ACK_RC'D_CODE = FALSE then\n \\text{REP\\_CODE} := \\text{FALSE};\n \\text{REPLY\\_TIMER} := 0;\n \\text{THREE\\_RPT\\_COUNTER} := 0;\n if RCVD_ACK = TRANS_ACK_ALT then\n if ACK_TO_COMPLETE_MSG = TRUE then\n \\text{PREPARE\\_TO\\_COMPLETE\\_MSG} := \\text{TRUE};\n else\n \\text{CAN\\_CODE} := \\text{TRUE};\n end if;\n end if;\n elseif RT_RECD_CODE = TRUE then\n \\text{CAN\\_CODE} := \\text{TRUE};\n \\text{REPLY\\_TIMER} := 0;\n \\text{THREE\\_RPT\\_COUNTER} := 0;\n exit;\n end if;\n if REPLY\\_TIMER \\neq 0 then\n exit;\n else\n \\text{REPLY\\_TIMER} := 0;\n \\text{TCC\\_TO\\_SEND} := \\text{TRUE};\n if THIRD\\_REP\\_SENT\\_W/O\\_RESPONSE then\n \\text{THREE\\_RPT\\_ALARM} := \\text{TRUE};\n end if;\n end if;\nend REPLY_TO_REP_OR_STOP;\nEOT..\nTHE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS FOR REPLYING TO EOM COMMAND AS DESCRIBED IN THE FOLLOWING:\n\nMANUAL PARAGRAPH(S)\n\nDCAC 370-D175-1 11-31\n\n01/19/82 RCR\n\nprocedure REPLY_TO_EOM is\n begin\n GENERATE_CONTROL_CHARACTERS;\n THIS PROCEDURE SATISFIES THE FOLLOWING REQUIREMENTS:\n if STOP RECD_CODE = TRUE then\n STOP RECD_CODE := FALSE;\n THRE_RPT_COUNTER := 0;\n elsif ACK RECD_CODE = TRUE then\n REPLY_TIMER := 0;\n if RECD_ACK = TRANS_ACK_ALT then\n PREPARE_TO_SEND_NEXT_MESSAGE := TRUE;\n else\n CAN_CODE := TRUE;\n end if;\n exit;\n elsif RT RECD_CODE = TRUE then\n REPLY_TIMER := 0;\n CAN_CODE := TRUE;\n if REPLY_TIMER_EXPIRED then\n REPLY_TIMER := 0;\n REP_CODE := TRUE;\n TCC_TO_SEND := TRUE;\n end if;\n end if;\n end REPLY_TO_EOM;\n EOT..\nTHE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS FOR SENDING A TCC SEQUENCE AS DESCRIBED IN THE FOLLOWING:\n\nMANUAL\n\nDCAC 370-D175-1\n\n01/15/82 RCR\n\nprocedure SEND_TCC_SEQUENCE is\nbegin\n GENERATE_CONTROL_CHARACTERS;\n this procedure satisfies the following requirements:\n if SEND GEN CODE = TRUE then\n SEND REP SEQUENCE;\n elsif CAN CODE = TRUE then\n SEND CAN SEQUENCE;\n end if;\n if REP CODE = TRUE and CAN CODE = TRUE then\n THREE_RPT_COUNTER := THREE_RPT_COUNTER + 1;\n if ACK1 = TRUE then\n ACK1 := FALSE;\n end if;\n if ACK2 = TRUE then\n ACK2 := FALSE;\n end if;\n if RT RECEIVED CODE = TRUE then\n RT RECEIVED CODE := FALSE;\n end if;\n if STOP RECEIVED CODE = TRUE then\n STOP RECEIVED CODE := FALSE;\n end if;\n START_REPLY_TIMER;\nelse\n SEND START SEQUENCE;\nend if;\nend SEND_TCC_SEQUENCE;\nEOT..\nTHE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS FOR THE TRANSMISSION OF THE TEXT PORTION OF A MESSAGE AS DESCRIBED IN THE FOLLOWING:\n\nMANUAL PARAGRAPH(S)\n\nDCAC 370-D175-1 11-24,25\n\nprocedure SELECT_ACKNOWLEDGEMENT_RESPONSE is\nbegin\n CAN_CODE := TRUE;\n loop\n loop\n if PAUSE_GENERATED = TRUE then\n SEND_GEN_CODE := TRUE;\n SEND_DET_CODE := FALSE;\n elsif SEND_DETECT_GENERATED = TRUE then\n SEND_DET_CODE := TRUE;\n end if;\n if RCC_TO_SEND = TRUE then\n SEND_RCC_SEQUENCE;\n exit;\n end if;\n if REPLY_TIMER_RUNNING = TRUE then\n if TIMING_REPLY_TO_CAN then\n REPLY_TO_CAN;\n exit;\n else if TIMING_REP_OR_STOP then\n REPLY_TO_REP_OR_STOP;\n exit;\n else\n REPLY_TO_EOM;\n exit;\n end if;\n end if;\n if TCC_TO_SEND = TRUE then\n SEND_TCC_SEQUENCE;\n exit;\n end if;\n if STOP_RECQ = TRUE then\n -- > START REPLY TIMER\n exit;\n elsif CAN_CODE = TRUE then\n exit;\n elsif MESSAGE_CHAR_TO_SEND \\= TRUE then\n if CANTRAN_CHAR_TO_SEND \\= TRUE then\n exit;\n end if;\n end if;\n\n connector 2 of requirements starts here\n\n if SEND_GEN_CODE = TRUE then\n -- > SEND START SEQUENCE\n SEND_GEN_CODE := FALSE;\n end if;\n\n 152\nelsif SEND_DET_CODE = TRUE then\n exit;\nend if;\n\n--> SEND A CHARACTER\nif LAST_CHAR_OF_EOMS then\n --> COMPLIMENT TRANSMIT ACK ALTERNATOR\n --> SET ALL RECEIVE CODES\n --> START REPLY TIMER\n REPLY_TO_EOM;\n exit;\nend if;\nend loop;\nif PREPARE_TO_SEND_NEXT_MESSAGE = TRUE then\n exit;\nend if;\nend loop;\nend SELECT_ACKNOWLEDGEMENT_RESPONSE;\nEOT..\nTHE PURPOSE OF THIS ROUTINE IS TO TRANSMIT MESSAGES AS A FUNCTION OF THE MODE OF TRANSMISSION OF THE LINE IN USE. THIS REQUIREMENT IS CONTAINED IN THE FOLLOWING:\n\nMANUAL PARAGRAPH(S)\n\nTT-B1-1101-0001A 3.2.1.2.15\nDCAC 370 D175-1 CHAPTER 5\n\n12/16/81 RCR\n\nprocedure TRANSMIT_MESSAGE is\nbegin\n case LINE_TRANSMISSION_TYPE is\n when SYNONCHRONOUS =>\n if SYNCHRONOUS_MODE = SYNCHRONOUS_BLOCK_BY_BLOCK then\n BLOCK_COUNT := BLOCK_FRAMED;\n TRANSMIT_SYNCHRONOUS_MESSAGE_BLOCK_BY_BLOCK;\n elsif SYNCHRONOUS_MODE = SYNCHRONOUS_CONTINUOUS then\n BLOCK_COUNT := 1;\n while BLOCK_COUNT <= NUMBER_BLOCKS loop\n TRANSMIT_SYNCHRONOUS_MESSAGE_BLOCK_BY_BLOCK;\n BLOCK_COUNT := BLOCK_COUNT + 1;\n end loop;\n end if;\n when ASYNCHRONOUS =>\n TRANSMIT_SYNCHRONOUS_MESSAGE;\n when OTHERS => ERROR_CODE := INVALID_TRANSMISSION_CODE;\n end case;\nend TRANSMIT_MESSAGE;\n\nEOT.\nSelect type of log entry\n\nType of Log Entry\n\nStart of Message Entry\n\nEnd of Message Entry\n\nCancel Message Entry\n\nScrubbed Message Entry\n\nCANTRAN Message\n\nSelected Message\n\nLog Entry\n\nA555\n\nUPDATE JOURNAL\nprocedure START_OF_MESSAGE_OUT_JOURNAL_ENTRY is\n begin\n OUTGOING_LOG_ENTRY := SOM_OUT_ENTRY;\n -- CREATE A JOURNAL ENTRY WHICH CONTAINS:\n -- OUTPUT CHANNEL ID\n -- CHANNEL SEQUENCE NUMBER, IF APPLICABLE\n -- CHANNEL MODE OF OPERATION\n -- ROUTING INDICATOR\n -- HEADER INFORMATION\n -- TIME SOM TRANSMITTED\n -- S&F ASSIGNED SERIAL NUMBER\n end START_OF_MESSAGE_OUT_JOURNAL_ENTRY;\nEOT..\nprocedure END_OF_MESSAGE_OUT_JOURNAL_ENTRY is\nbegin\n OUTGOING_LOG_ENTRY := EOM_OUT_ENTRY;\n -- CREATE A JOURNAL ENTRY WHICH CONTAINS:\n -- ENTRY IDENTIFICATION\n -- OUTPUT CHANNEL ID\n -- TIME OF TRANSMISSION\n -- CHANNEL SEQUENCE NUMBER\n -- DESTINATIONS FOR THIS MESSAGE\n -- S&F ASSIGNED SERIAL NUMBER\n -- BLOCK COUNT\nend END_OF_MESSAGE_OUT_JOURNAL_ENTRY;\nEOT..\n-- A553\n-- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\n-- FOR CANCEL MESSAGE JOURNAL ENTRIES AS DESCRIBED IN THE FOLLOWING:\n-- MANUAL PARAGRAPH(S)\n-- TT-B1-1101-0001A 3.2.1.2.14.1.2(c)\n-- 01/19/82 RCR\n\nprocedure CANCEL_MESSAGE_OUT_JOURNAL_ENTRY is\nbegin\n OUTGOING_LOG_ENTRY := CANCEL_OUT_ENTRY;\n -- CREATE A JOURNAL ENTRY WHICH CONTAINS:\n -- CHANNEL ID AND CSN\n -- CHANNEL MODE OF OPERATION\n -- TIME OF CANCELLATION\n -- REASON FOR CANCELLING\n -- ROUTING INDICATORS OF MESSAGE\n -- S&F MODULE ASSIGNED SERIAL NUMBER\n -- BLOCK COUNT\nend CANCEL_MESSAGE_OUT_JOURNAL_ENTRY;\n\nEOT..\n-- A554\n-- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE REQUIREMENTS\n-- FOR SCRUBBED MESSAGE JOURNAL ENTRIES AS DESCRIBED IN THE FOLLOWING:\n-- MANUAL PARAGRAPH(S)\n-- TT-B1-1101-0001A 3.2.1.2.14.1.2(d)\n-- 01/19/82 RCR\n\nprocedure SCRUBBED_MESSAGE_OUT_JOURNAL_ENTRY is\n begin\n OUTGOING LOG ENTRY := SCRUB ENTRY;\n -- CREATE A JOURNAL ENTRY WHICH CONTAINS:\n -- CHANNEL ID AND CSN\n -- CHANNEL MODE OF OPERATION\n -- TIME SCRUBBED\n -- S&F MODULE ASSIGNED SERIAL NUMBER\n -- ROUTING INDICATORS OF MESSAGE\n -- REASON FOR SCRUB\n -- BLOCK COUNT\n if MESSAGE OUT SENT TO OVERFLOW then\n -- INCLUDE OVERFLOW MESSAGE SERIAL NUMBER\n end if;\n if MESSAGE SENT TO INTERCEPT then\n -- INCLUDE INTERCEPT MESSAGE SERIAL NUMBER\n end if;\n end SCRUBBED_MESSAGE_OUT_JOURNAL_ENTRY;\n\nEOT..\n--- THE PURPOSE OF THIS ROUTINE IS TO DESCRIBE THE\n--- REQUIREMENTS FOR JOURNAL ENTRY CREATION AS A RESULT\n--- OF MESSAGE OUTPUT PROCESSING AS DESCRIBED IN THE\n--- FOLLOWING:\n--- MANUAL PARAGRAPHS\n--- TT-B1-1101-0001A 3.2.1.2.14.1.2\n--- 12/15/81\n\nprocedure UPDATE_JOURNAL is\nbegin\n case JOURNAL_ENTRY_TYPE is\n when START_OF_MESSAGE_CODE =>\n START_OF_MESSAGE_OUT_JOURNAL_ENTRY;\n when END_OF_MESSAGE_CODE =>\n END_OF_MESSAGE_OUT_JOURNAL_ENTRY;\n when CANCEL_MESSAGE_CODE =>\n CANCEL_MESSAGE_OUT_JOURNAL_ENTRY;\n when SCRUBBED_MESSAGE_CODE =>\n SCRUBBED_MESSAGE_OUT_JOURNAL_ENTRY;\n when CANTTRAN_MESSAGE_CODE =>\n CANTTRAN_MESSAGE_OUT_JOURNAL_ENTRY;\n end case;\nend UPDATE_JOURNAL;\n\nEOT..\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nO1A3\nACKNOWLEDGMENT\n= [ACK REQUEST|ACK RECEIVED]\n* USED TO PASS REQUEST TO\nSEND ACK OR TO PASS ACKS\nWHICH HAVE BEEN RECEIVED TO\nTHE TRANSMIT FUNCTION *\n\nACP_FMT_LN_1\n= 'VZCZC' + ICD + FIGS\n+ ICSN + LTRS + <5>'b'\n+ ([UU|HH]) + LN END\n* TRANSMISSION IDENT (TI) *\n\nACP_FMT_LN_2\n= (BELL SIGNAL) +\nDOUBLE PRECEDENCE PROSIGN +\n<..>'b' + RI + LN END\n\nACP_FMT_LN_3\n= 'DEb' + RI + 'b' + ('#' +\nACP_SSN + [DATE_TIME]DATE +\n'/'+ TIME + 'Z') +\nLN_END\n\nACP_FMT_LN_15\n= (CORRECTION) + (EOM_SEQ)\n\nACP_HEADER\n= ACP_FMT_LN_1 + ACP_FMT_LN_2\n+ ACP_FMT_LN_3 + (FMT_LN 4)\n+ (FMT_LN-5) + (FMT_LN 6) +\n(FMT_LN_7) + (FMT_LN_8) +\n(FMT_LN_9) + (FMT_LN_10)\n\nACP_MESSAGE\n= ACP_HEADER + SEPARATOR +\nBODY + SEPARATOR +\nACP_TRAILER\n\nACP_PILOT\n= ACP_FMT_LN_2 + FMT_LN 4 +\nICD + ICSN + <5>'b' +\n([UU|HH]) + LN END\n\nACP_SSN\n= <3>(DIGIT) + (LETTER)\n* ORIGINATING STATION\nSERIAL NUMBER *\n\nARRI\n= <7>(['b']LETTER)\n\nACP_TRAILER\n= (FMT_LN_14) +\nACP_FMT_LN_15\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nASN\n = TBD\n * ASSIGNED SER NO\n USED TO DIFFERENTIATE A\n PARTICULAR MESSAGE FROM ALL\n OTHER SYSTEM MESSAGES *\n\nASYNCHRONOUS_MODE\n = [ NORMAL ; STEPPED ]\n *TRANSMISSION METHOD*\n\nASYNCH.Receive_CONTROL_CHAR\n = [ACK 1; ACK 2; STOP; RT]\n * CHARACTER *\n\nBELL_SIGNAL\n = FIGS + <5>('J') +\n <5>('S') + LTRS\n\nBODY\n = <0..>(CHARACTER)\n * TEXT OF MESSAGE *\n\nBP\n = CHARACTER\n * BLOCK PARITY OF MESSAGE\n FORMED BY THE BINARY\n ADDITION WITHOUT CARRY\n (XOR) OF THE BITS IN EACH\n ROW OF A BLOCK AND PLACED\n IN THE LAST FRAMING\n CHARACTER OF A\n SYNCHRONOUS MESSAGE. *\n\nBP_CALC\n = * CUMULATIVE BLOCK PARITY\n CALCULATION DURING THE\n SYNCHRONOUS RECEIVE\n PROCESS STARTING WITH THE\n 2ND FRAMING CHAR AND\n ENGING WITH \"ETX\" OR\n \"ETB\" *\n\nCAN_CODEC\n = [TRUE ; FALSE ]\n\nCANCEL_OUT_ENTRY\n = OCD + OCSN + DATE_TIME +\n + ASN\n + CHANNEL MODE\n + CANCEL_REASON\n + <1..50>(RI)\n + NUMBER_BLOCKS\n * MADE WHEN A CANCELLATION\n IS TRANSMITTED *\n\nCANCEL_REASON\n = TBD\n\n163\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nCANCEL_REC_ENTRY = ICD + ICSN + DATE TIME + CHANNEL_MODE + NUMBER_BLOCKS + ASN\n* MADE WHEN A CANCEL IS RECEIVED *\n\nCANTRAN_CHAR_TO_SEND = [ TRUE ; FALSE ]\n\nCANTRAN_REC_ENTRY = ICD + ICSN + DATE TIME + CHANNEL_MODE + NUMBER_BLOCKS + ASN\n* MADE WHEN A CANCEL IS RECEIVED *\n\nCANTRAN_OUT_ENTRY = OCD + OCSN + DATE TIME + CHANNEL_MODE + NUMBER_BLOCKS + ASN\n* MADE WHEN A CANTRAN IS TRANSMITTED *\n\n0xA4234 . CARD_CHECKED_MESSAGES\nI1A4235\nI1A4236\n\nCARD_FMT_LN_2 = PRECEDENCE + LMF_PAIR + CLASS + CIC_CAI + 'b' + OSRI + OSSN + 'b' + DATE_TIME + 'b' + RECORD_COUNT + '-' + '-' + RI + <0..49>(RI) + 'b' +\n\n0x1A4234 . CARD_INFO\n\nCARD_MESSAGE = <28>({FROM_CARD|TO_CARD|NO})\n* TABLE KEtED BY TRANSLATION_PAIR.\n(CA;CT;CT' => FROM_CARD,\nTC;QC;AC;FC => TO_CARD,\nOTHERS => NO) *\n\n01A4235 . CARD_TRANSLATED_MESSAGES\n01A4236\nIxA4237\n\nCHANNEL_MODE = [1;2;3;4;5]\n<table>\n<thead>\n<tr>\n<th>Description</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CHAR</td>\n<td>= SEE CHARACTER</td>\n</tr>\n<tr>\n<td>OxA4231 CHAR_CHECKED_MESSAGE</td>\n<td>= MESSAGE + MCB + TRANSLATION_PAIR</td>\n</tr>\n<tr>\n<td>I1A4232</td>\n<td></td>\n</tr>\n<tr>\n<td>I1A4233</td>\n<td></td>\n</tr>\n<tr>\n<td>01A4232 CHAR_TRANSLATED_MESSAGE</td>\n<td>= MESSAGE + MCB + TRANSLATION_PAIR</td>\n</tr>\n<tr>\n<td>01A4233</td>\n<td></td>\n</tr>\n<tr>\n<td>IxA4234</td>\n<td></td>\n</tr>\n<tr>\n<td>C1A4231 CHAR_SET_INFO</td>\n<td>= <28>([ITA;ASCII;NO])</td>\n</tr>\n<tr>\n<td></td>\n<td>* TABLE KEYED BY TRANSFORMATION PAIR.</td>\n</tr>\n<tr>\n<td></td>\n<td>(CT</td>\n</tr>\n<tr>\n<td></td>\n<td>TC</td>\n</tr>\n<tr>\n<td></td>\n<td>OTHERS => NO) *</td>\n</tr>\n<tr>\n<td>CHARACTER</td>\n<td>= LEVEL + [TEXT_CHARACTER</td>\n</tr>\n<tr>\n<td>CHARACTER_PARITY</td>\n<td>= ASCII + [EVEN</td>\n</tr>\n<tr>\n<td>CHNL_DES</td>\n<td>= <3>(LETTER)</td>\n</tr>\n<tr>\n<td></td>\n<td>* CHANNEL DESIGNATOR *</td>\n</tr>\n<tr>\n<td>CIC_CAI</td>\n<td>= <3>(LETTER) + [LETTER</td>\n</tr>\n<tr>\n<td></td>\n<td>* CONTENT INDICATOR CODE -- CONTENT ACTION INDICATOR *</td>\n</tr>\n<tr>\n<td>CLASS</td>\n<td>= [M</td>\n</tr>\n<tr>\n<td></td>\n<td>* CLASSES ARE:</td>\n</tr>\n<tr>\n<td></td>\n<td>M -- DSSCS</td>\n</tr>\n<tr>\n<td></td>\n<td>A -- SPECAT</td>\n</tr>\n<tr>\n<td></td>\n<td>T -- TOP SECRET</td>\n</tr>\n<tr>\n<td></td>\n<td>S -- SECRET</td>\n</tr>\n<tr>\n<td></td>\n<td>C -- CONFIDENTIAL</td>\n</tr>\n<tr>\n<td></td>\n<td>R -- RESTRICTED</td>\n</tr>\n<tr>\n<td></td>\n<td>E -- EFTO</td>\n</tr>\n<tr>\n<td></td>\n<td>(ENCRYPT FOR TRANSMISSION ONLY)</td>\n</tr>\n<tr>\n<td></td>\n<td>U -- UNCLASSIFIED</td>\n</tr>\n<tr>\n<td>CLASS_X5</td>\n<td>= <5>(CLASS)</td>\n</tr>\n<tr>\n<td>C1A411 COLLECTIVE_RI_TABLE</td>\n<td>= <0..200>(RI +<1..50>(LINE_NO))</td>\n</tr>\n<tr>\n<td>O1A411 COLLECTIVE_ROUTED_MESSAGES</td>\n<td>= MESSAGE + MCB +<1..50>(OUTPUT_LINE_NUMBER)</td>\n</tr>\n<tr>\n<td>I1A412</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nCOMMUNITIES_SERVED = (R) + (U) + (Y)\n\nCONTROL_CHARACTER = [ASCII.NUL..ASCII.US!\nASCII.DEL|ITA.LTRS|\nITA.FIGS|ITA.CR|ITA.CR|\nITA.LF|ITA.BLANK]\n\nCONTROL_CODE = [SEND_STOP|RT_RCVD|SEND_RT|\nEOMS_RCVD|STOP_RCVD|\nACK_1_RCVD|ACK_2_RCVD|\nCANCEL_RCVD|REPLY_RCVD|\nSEND_RM|SEND_ACK|SEND_NAK|\nWBT_RCVD|RM_RCVD|NAK_RCVD|\nINVALID_RCVD|\nINVALID_CHAR |\nENQUIRY_RCVD]\n\n*USED TO SIGNAL CONDITIONS TO GENERATE_CONTROL\nCHARACTERS -*\n\nCORRECTION = 'C' + <..<>(CHARACTER) + LN_END\n\nCURRENT_LIST = TBD\n\nDATA_MODE = FORMAT + LEVEL\n\nDATA_STATE = [TRUE|FALSE]\n\n* TRUE, SYNCHRONOUS RECEIVER WILL ACCEPT TEXT CHARACTERS\nFALSE, WILL ACCEPT CONTROL AND SYNC CHARACTERS *\n\nDATE = <2>(DIGIT)\n\n* DAY OF MONTH *\n\nDATE_TIME = <7>DIGIT\n\n* JULIAN DATE PLUS ZULU TIME *\n\nDELS_CHECKED_MESSAGE = MESSAGE + MCB +\nTRANSFORMATION_PAIR\n\nDELS_INFO = <28>([YES|NO])\n\n* TABLE KEYED BY TRANSFORMATION_PAIR\n(AC|AT|AT' => YES,\nOTHERS => NO ) *\n\n166\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nDIRECTION = (INPUT) + (OUTPUT)\n* BOTH SET IMPLIES 2-WAY *\n\nDOUBLE_PRECEDENCE_PROSIGN = <2>(PRECEDENCE)\n* USED IN ACP_FMT_LN_2 *\n\nECSN = <3>(DIGIT)\n* EXPECTED CHANNEL SEQUENCE NUMBER *\n\nEOM_IN_ENTRY\n= ICD + ICSN + DATE TIME +\n ASN + NUMBER_BLOCKS +\n CHANNEL MODE\n* MADE WHEN EOM IS RECEIVED *\n\nEOM_OUT_ENTRY\n= OCD + OCSN + DATE TIME +\n ASN + <1..50>(RI) +\n NUMBER_BLOCKS\n* MADE WHEN EOM IS TRANSMITTED *\n\nEOM_SEQ\n= <2>(CR) + <8>(LF) +\n <4>('N') + <8>(LTRS)\n\nEOM_VALIDATION\n= ' #' + <4>(DIGIT)\n\nEOT_CARD\n= PRECEDENCE + LMF PAIR +\n CLASS + CIC_CAI + 'b' + OSRI +\n OSSN + 'b' + DATE TIME +\n 'b' + RECORD_COUNT + '-' +\n REDUNDANT_CLASS +\n <44>('b') + <4>('N')\n* N'S START IN COLUMN 72 *\n\nERROR_CODE\n= [ NO ERROR ;\n INVALID_LENGTH ;\n INVALID_LINE RI ;\n INVALID_LMF ;\n INVALID_RI_SECURITY ;\n BAD BLOCK COUNT ;\n INVALID_LINE_TRANSMISSION_TYPE ]\n* CODES TO INDICATE ERROR CONDITION *\n\n0xA4237 FILL_CHECKED_MESSAGE\nI1A4238 = MESSAGE + MCB +\n TRANSLATION_PAIR\n\n167\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nC1A4237 FILL_INFO = <28>((YES; NO))\n* TABLE KEYED BY\nTRANSLATION PAIR\n(CA|CT|CT'|AT|AT'|QA|FA =>\nYES, OTHERS => NO) *\n\nFIRST_LMF_CHARACTER = [B|D|I|S;C|A|T|R;Q|F]\n\nFMT_LN_4 = OP_SIGNAL + CLASS_X5 +\n<0..>(CHARACTER) + LN_END\n\nFMT_LN_5 = PRECEDENCE +\n(|'b' + PRECEDENCE)\n+ 'b' + DATE + TIME + 'b' +\nMONTH + 'b' + YEAR\n+ <0..>(CHARACTER) + LN_END\n\nFMT_LN_6 = 'FMb' + <..>(CHARACTER) +\nLN_END\n\nFMT_LN_7 = 'TOb' + <..>(CHARACTER) +\nLN_END\n\nFMT_LN_8 = 'INFOb' + <..>(CHARACTER) +\nLN_END\n\nFMT_LN_9 = 'XMTb' + <..>(CHARACTER) +\nLN_END\n\nFMT_LN_10 = <..>(CHARACTER) + LN_END\n\nFMT_LN_14 = <..>(CHARACTER) + LN_END\n\nFORMAT = [JANAP_128 ; ACP_127]\n* MESSAGE FORMAT-*\n\n0xA4221 FORMAT_CHECKED_MESSAGE = MESSAGE + MCB +\nTRANSLATION_PAIR\n\nIA14222\nI1A4223\n\n01A4222 FORMAT_CONVERTED_MESSAGE = MESSAGE + MCB +\nTRANSLATION_PAIR\n\n01A4223\nIxA4224\n\nC1A4221 FORMAT_INFO = <28>((TO_127; TO_128; NO))\n* TABLE KEYED BY\nTRANSLATION PAIR.\n(CT|AT'|TT|RT|QT =>\nTO_127, FC|FA|FT =>\nTO_128, OTHERS => NO) *\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nHEADER = [JANAP_HEADER; CARD_FMT_LN_2; SINGLE_CARD; ACP_HEADER]\n\nICD = <3>(CHARACTER)\n* INCOMING CHANNEL ID *\n\nICSN = <3>(DIGIT)\n* INCOMING CHANNEL SER NO *\n\nINCOMING_LOG_ENTRY = [SOM_IN_ENTRY; EOM_IN_ENTRY; REJECT_ENTRY; CANCEL_REC_ENTRY; CANTRAN_REC_ENTRY]\n\nO1A412 INDIVIDUAL_ROUTED_MESSAGES = MESSAGE + MCB +\n<1..50>(OUTPUT_LINE_NUMBER)\n\nI1A413 INPUT_STREAM = <..>(BIT)\n\nI3A3 INCEPT_IN_ENTRY = HEADER + ASN + DATE_TIME +\nMCB + NUMBER_BLOCKS\n* MADE WHEN MESSAGE RECEIVED FROM INTERCEPT *\n\nO1A1331 INTERCEPT_LIST = TBD\n\nI1A1332 INTERCEPT_LOG_ENTRY = [INTERCEPT_IN_ENTRY;\nINTERCEPT_OUT_ENTRY]\n\nO2A43 INTERCEPT_OUT_ENTRY = ASN + HEADER + DATE_TIME +\n<1..50>(RI) + NUMBER_BLOCKS\n* MADE WHEN MESSAGE SENT TO INTERCEPT *\n\nINVALID_CHAR = ASCII.BEL(16#07#)\n\nJANAP_FMT_LN_1 = 'VZCZC' + ICD + FIGS\n+ ICSN + LTRS + LN_END\n* TRANSMISSION IDENT (TI) *\n\nJANAP_FMT_LN_2 = PRECEDENCE + LMF_PAIR +\nCLASS + CIC_CAI + 'b' + OSRI\n+ OSSN + 'b' + DATE_TIME +\n'- ' + REDUNDANT_CLASS +\n'- ' + RI + <0..49>(RI) +\n'.' + LN_END\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nJANAP_FMT_LN_3 = 'DEb' + RI + OSSN + DATE_TIME + LN_END\n\nJANAP_FMT_LN_15 = (CORRECTION) + (EOM_VALIDATION)\n\nJANAP_FMT_LN_16 = EOM_SEQ\n\nJANAP_HEADER = (JANAP_FMT_LN_1) + (JANAP_PILOT) + (JANAP_FMT_LN_3) + (JANAP_FMT_LN_3) + (FMT_LN_4) + (FMT_LN_5) + (FMT_LN_6) + (FMT_LN_7) + (FMT_LN_8) + (FMT_LN_9) + (FMT_LN_10)\n\nJANAP_MESSAGE = [CARD_MESSAGE;TTY_MESSAGE]\n\nJANAP_PILOT = PRECEDENCE + LMF_PAIR + CLASS + CIC_CAI + 'b' + OSRI + OSSN + 't' + DATE_TIME + '-' + REDUNDANT_CLASS + RECORD_COUNT + '---' + RI + <0..49>(RI) + '...' + LN_END\n* RECORD_COUNT MUST BE RI *\n\nJANAP_TRAILER = (FMT_LN_14) + (JANAP_FMT_LN_15) + JANAP_FMT_LN_16\n\nLEVEL = [5;8]\n* 5 LEVEL = ITA #2\n8 LEVEL = ASCII *\n\nLINE_AVAILABLE = TBD\n<table>\n<thead>\n<tr>\n<th>Code</th>\n<th>Description</th>\n<th>Details</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>C1A42</td>\n<td>LINE_DATA</td>\n<td>CHANNEL MODE + [SYNCHRONOUS MODE; ASYNCHRONOUS MODE] + DATA MODE + LOGICAL LINE NO + PHYSICAL LINE NO + LOOP SPEED + COMMUNITIES SERVED + (FIRST_LINK) + MAX NO RIS PER DELIV + (SOM_SEQ) + DIRECTION + ECSN + OCSN + CHNL_DES + (RCSN) + (NO_STOP_BITS) + (SECURITY_PROSIGN) + (SPEC_TERM) + LINE_AVAILABLE</td>\n</tr>\n<tr>\n<td>C1A43</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C1A421</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C1A431</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>O1A421</td>\n<td>LMF_MESSAGES</td>\n<td>MESSAGE + MCB + TRANSLATION_PAIR</td>\n</tr>\n<tr>\n<td>I1A422</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I1A4221</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>LMF_PAIR</td>\n<td></td>\n<td>FIRST LMF_CHARACTER + SECOND LMF_CHARACTER</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>* LEGAL PAIRS ARE: TT TA TC AT AA AC CC CA CT RT SC BB CC II QT FT *</td>\n</tr>\n<tr>\n<td>LN_END</td>\n<td></td>\n<td><2>(CR) + LF</td>\n</tr>\n<tr>\n<td>I2A1</td>\n<td>LOG_DATA</td>\n<td><0..>(LOG_ENTRY)</td>\n</tr>\n<tr>\n<td>I2A2</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I2A12</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I2A13</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I2A121</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I2A132</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I2A133</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I1A1321</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I1A1331</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>O3A3</td>\n<td>LOG_ENTRY</td>\n<td>[INCOMING LOG_ENTRY; OUTGOING_LOG_ENTRY; OVERFLOW_LOG_ENTRY; INTERCEPT_LOG_ENTRY; SVC_GEN_ENTRY]</td>\n</tr>\n<tr>\n<td>O3A4</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>O3A5</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>LOG_ENTRY_INFO</td>\n<td></td>\n<td>INCOMING_LOG_ENTRY * EXCEPT_CANTRAN *</td>\n</tr>\n<tr>\n<td>MAX_NO_RIS_PER_DELIV</td>\n<td></td>\n<td>[1;6;14;50;500]</td>\n</tr>\n</tbody>\n</table>\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nMCB = 'SOH' + SELECT_CHARACTER + PRECEDENCE + LMFPAIR + CLASS + CIC_CAI + 'b' + OSRI + OSSN + 'b' + DATE_TIME + NUMBER_BLOCKS + SOH_TIME + TRIP + SDC + TDW + SDO + TASC + SASC + ARRI + SMRI + ICD + TMID + ICSN + 'ETB' + BP\n\nMESSAGE = [JANAP_MESSAGE ; ACP_MESSAGE]\n\nMESSAGE_CHAR_TO_SEND = [TRUE ; FALSE ]\n* CHARACTER AVAILABILITY\n\nMESSAGE_DATA = MESSAGE\n\nMESSAGE_DATA_A = MESSAGE\n* NOTE: ON MESSAGE_DATA_A THROUGH MESSAGE_DATA_D, LEXICALLY GREATER DISTINGUISHING LETTERS INDICATE PROGRESSIVELY MORE COMPLETE VALIDATION *\n\nMESSAGE_DATA_B = MESSAGE\n\nMESSAGE_DATA_C = MESSAGE\n\nMESSAGE_DATA_D = MESSAGE\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nMESSAGE_DATA_C = MESSAGE\n\nMESSAGE_DATA_D = MESSAGE\n\nMESSAGE_CANCELLED = [ TRUE ; FALSE ]\n\nMESSAGE_IN_TRANSMISSION = [ TRUE ; FALSE ]\n\nMESSAGE_MODE = [ JANAP 128 ; ACP_127 ; ACP_127 MOD ]\n\nMESSAGE_REJECTION = SEND RM\n\n* USED TO SIGNAL\nMESSAGE REJECTION\n\nTO GENERATE CONTROL\nCHARACTER FUNCTION *\n\nMONTH = [JAN:FEB ... DEC]\n\n* 3 LETTER MONTH NAMES *\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nO3A1 NEW_INTERCEPT_FILE = <O..>(MESSAGE + MCB)\nO2A13\nO1A133\nO1A1332\nI1A4\n\nO4A1 NEW_OVERFLOW_FILE = <O..>(MESSAGE + MCB)\nO2A13\nO1A132\nO1A1322\nI2A3\n\nNEW_ROUTE_LINE = ROUTE_LINE\n\nNO_ERROR\n\nNUMBER_BLOCKS = <3>(DIGIT)\n\nOASC = ['b'!LETTER]\n\nOCCUPANCY_LEVEL = [0..'00]\n\nOCD = <3>(CHARACTER)\n\nOCSN = <3>(DIGIT)\n\nOP_SIGNAL = ['ZNY';'ZNR']\n\n01A2 OPERATOR_COMMAND = [REINTRODUCE_COMMAND;\nTRACE_COMMAND;\nRETRIEVE_COMMAND;\nRECOVERY_COMMAND;\nTHROTTLE_COMMAND;\nDRY_UP_COMMAND;\nCHANNEL_COMMAND;\nTAPE_COMMAND;\nSTATISTICS_COMMAND;\nMESSAGE_CONTROL_COMMAND;\nDESTRUCT_COMMAND;\nROUTING_COMMAND;\nEQUIPMENT_COMMAND;\nTABLE_COMMAND]\n\n01A2 OPERATOR_PRINTOUTS = TBD\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nOSRI = RI\n* ORIGINATING STATION ROUTING INDICATOR *\n\nOSSN = <4>(DIGIT)\n* ORIGINATING STATION SERIAL NUMBER *\n\nOUTGOING_LOG_ENTRY = [SOM_OUT_ENTRY;\nEOM_OUT_ENTRY;\nCANCEL_OUT_ENTRY;\nSCRUB_ENTRY;\nCANTRAN_OUT_ENTRY]\n\nOUTPUT_LINE_TYPE = [ TRIBUTARY | TRUNK ]\n\nOUTPUT_LINE_NUMBER = [1..50]\n\nOUTPUT_SELECTED_MESSAGE = MESSAGE + MCB\n\nOUTPUT_STREAM = <..>(BIT)\n\nOVERFLOW_IN_ENTRY = HEADER + ASN + DATE_TIME +\nMCB + NUMBER_BLOCKS\n* MADE WHEN MESSAGE RECEIVED FROM OVERFLOW *\n\nOVERFLOW_LIST = TBD\n\nOVERFLOW_LOG_ENTRY = [OVERFLOW_IN_ENTRY;\nOVERFLOW_OUT_ENTRY]\n\nOVERFLOW_OUT_ENTRY = ASN + HEADER + DATE_TIME +\nNUMBER_BLOCKS\n* MADE WHEN MESSAGE SENT TO OVERFLOW *\n\nPAUSE_GENERATED = [ TRUE | FALSE ]\n\n175\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nPRECEDENCE\n= [W;Y;Z;O;P;R]\n * PRECEDENCES ARE:\n W -- CRITIC\n Y -- ECP\n Z -- FLASH\n O -- IMMEDIATE\n P -- PRIORITY\n R -- ROUTINE *\n\nPREPARE_TO_SEND_MESSAGE\n= [ TRUE ; FALSE ]\n * INDICATES COMPLETION\n OF MESSAGE *\n\nI3A1 PROGRAM_LOAD_FILE\n= TBD\n\nO4A2 PROGRAM_LOAD_INSTRUCTIONS\n= TBD\n\nIxA5426 RCC_TO_SEND\n= [ TRUE ; FALSE ]\n\nRCSN\n= <3>DIGIT\n * REJECTED CHANNEL SEQUENCE\n NUMBER *\n\nRECORD_COUNT\n= [<4>(DIGIT);'MTMS';'PLTS';\nRI]\n * RI--MS RI (4 LETTERS) *\n\nO3A1 RECOVERED_MESSAGES\n= <0..>(MESSAGE + MCB)\n\nO1A12\n\nO1A121\n\nI1A3\n\nO2A11 RECOVERY_COMMAND\n= TBD\n\nC1A12\n\nC1A121\n\nREDUNDANT_CLASS\n= <4>(CLASS)\n\nO4A3 REFERENCE_COPY\n= MESSAGE + MCB\n\nI1A1 REFERENCE_DATA\n= <0..>(MESSAGE + MCB)\n<table>\n<thead>\n<tr>\n<th>Code</th>\n<th>Description</th>\n<th>Value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>01A422</td>\n<td>Reformatted_Message</td>\n<td>Message + MCB + Translation_Pair</td>\n</tr>\n<tr>\n<td>01A4225</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I1A423</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>I1A4231</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C2A43</td>\n<td>Reintroduce_Command</td>\n<td>TBD</td>\n</tr>\n<tr>\n<td>C2A432</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Reject_Entry</td>\n<td>Date Time + Reject_Reason + ASN + Channel_Mode + ICD + ICSN</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>* Made When A Message Is Rejected By The Switch *</td>\n</tr>\n<tr>\n<td></td>\n<td>Reject_Reason</td>\n<td>TBD</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Reply</td>\n<td>Protocol Command</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>* Sent By The Transmitting Station To Direct The Receiver To Send Its Current Status *</td>\n</tr>\n<tr>\n<td></td>\n<td>Reply_Character</td>\n<td>ASCII. DC1(16#11#)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Request_for_answer_char</td>\n<td>[Transmit_Control_Char ; BP_Char ]</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>RI</td>\n<td>[R</td>\n</tr>\n<tr>\n<td>C1A412</td>\n<td>RI_Line_Table</td>\n<td><0..1500>(RI+LINE_NO)</td>\n</tr>\n<tr>\n<td>C1A41</td>\n<td>Route_Data</td>\n<td>TBD</td>\n</tr>\n<tr>\n<td>C1A332</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C1A333</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C1A334</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C1A335</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C1A3323</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C1A3332</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C1A3344</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>C1A3352</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Route_Line</td>\n<td>[JANAP_FMT_LN_2 ; ACP_FMT_LN_2 ; CARD_FMT_LN_2]</td>\n</tr>\n<tr>\n<td>C2A4</td>\n<td>Route_Line_Data</td>\n<td>TBD</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nO1A41 ROUTED_MESSAGE = MESSAGE + MCB\nO1A413\nI1A42\nI1A421\n\nO1A331 ROUTED_MESSAGE_DATA = MESSAGE\nO2A331\nO3A331\nO4A331\nI1A332\nI1A333\nI1A334\nI1A335\nI1A3321\nI1A3331\nI1A3341\nI1A3351\n\nSASC = ['b'|LETTER]\nIxA5426 SEND_DET_CODE = [ TRUE ; FALSE ]\nIxA5426 SEND_DET_GENERATED = [ TRUE ; FALSE ]\n\nSCRUB_ENTRY = OCD + OCSN + CHANNEL_MODE + DATE_TIME + ASN + SCRUB_REASON + NUMBER_BLOCKS\n<1..50>(RI)\n* MADE WHEN A MESSAGE IS SCRUBBED *\n\nSEND_GEN_CODE = [ TRUE ; FALSE ]\nSCRUB_REASON = TBD\nSDC = ['b'|S|C|P|M|T|A]\nSDO = ['b'|LETTER]\nSECOND_LMF_CHARACTER = [B|D|I|C|A|T]\nSECURITY_PROSIGN = [A|T|S|C|R|E|U|M]\nSELECT_CHARACTER = [A|B|C|D|E|F|G|H|J|K|M|P|S]\nSEPARATOR = 'BT' + LN_END\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\n01A4 SERVICE_MESSAGE_INFO = SVC MESSAGE_TYPE + MESSAGE + \\(0^{.50}\\)(RI) + \\(<2\\)\\)(ICSN)\n\n01A42\n02A422\n02A4223\n01A5\n01A332\n01A333\n01A334\n01A335\n01A3321\n02A3322\n02A3323\n01A3324\n01A3325\n01A3331\n01A3332\n01A3333\n01A3334\n01A3342\n02A3343\n02A3344\n01A3345\n01A3346\n01A3351\n01A3352\n01A3353\n01A3354\nC2A3\n\nSINGLE_CARD = PRECEDENCE + LMF_PAIR + CLASS + CIC_CAI + 'b' + OSRI + OSSN + 'b' + DATE_TIME + '-' + RI + '. ' + \\(<41\\)\\)(CHARACTER) + 'N'\n* FINAL N MUST BE IN COLUMN 80 *\n\nSMRI = \\(<5\\)\\)(LETTER)\n\nSOH_TIME = DATE_TIME\n* TIME OF RECEPTION OF START OF HEADER *\n\nSOM_IN_ENTRY = CHANNEL_MODE + HEADER + DATE_TIME + ASN + ICD + ICSN + MCB\n* MADE WHEN START OF MESSAGE RECEIVED *\n\n179\nDATA DICTIONARY\nFEBRUARY 8, 1982\n\nSOM_OUT_ENTRY = OCD + OCSN + CHANNEL_MODE + <1..50>(RI) + HEADER + DATE_TIME + ASN\n* MADE WHEN START OF MESSAGE TRANSMITTED *\n\nSOM_SEQ = [ FULL ; ABBREVIATED ]\n\nSORTED_MESSAGE = MESSAGE + MCB\n\nSPEC_TERM = [ ACCESS | INTERSWITCH | TECH_CONTROL ]\n\nSTART_COMMAND = TBD\n\nSTOP_RECD_CODE = [ TRUE | FALSE ]\n\nSVC_GEN_ENTRY = HEADER + ASN + DATE_TIME + MCB + NUMBER BLOCKS\n* MADE WHEN SERVICE MESSAGE IS GENERATED *\n\nSVC_MESSAGE_TYPE = [ INVALID RI;\nOUTPUT SCTY MISMATCH;\nEXCESSIVE ROUTING REJ;\nILLEGAL EXCHANGE;\nSUSPENDED TRANSMISSION;\nSUSPECTED STRAGGLER;\nOPEN CSN;\nINPUT SCTY MISMATCH;\nINVALID SCTY FIELD;\nINVALID HEADER REJ;\nINVALID HEADER ACC;\nHI PREC ACC;\nINVALID RI FIELD;\nALL RI INVALID;\nINVALID TI REJ;\nINVALID TI ACC;\nTWO CONSEC.SOM;\nINVALID EOM REJ;\nINVALID EOM ACC;\nINCORRECT CSN;\nINVALID BLOCK_COUNT;\nTRAFFIC_CHECK;\nNO_EOM ]\nSYNCH_RECEIVE_CONTROL_CHAR = [ACK 1 | ACK 2 | NAK | RM | WBT] * CHARACTER *\nSYNCHRONOUS_MODE = [BLOCK_BY_BLOCK | CONTINUOUS]\n\nO3A2 TABLE_CHANGES = TBD\n\nO1A1\nO1A11\n\nTASC = ['b';LETTER]\n\nIxA5426 TCC_TO_SEND = [ TRUE ; FALSE ]\n\nTDW = <12>(CHARACTER)\n\nTEXT_CHARACTER = [ASCII.BLANK..ASCII.TILDE ; * PRINTABLE ITA CHARACTERS]\n\nTHRESHOLD_STATUS = [UPPER;UPPER MIDDLE; LOWER MIDDLE;LOW]\n\nTIME = <4>(DIGIT) + 'Z'\n\nT MID = <8>(CHARACTER)\n\nIxA5426 TIMING_REPLY_TO_CAN = [TRUE ; FALSE ]\n\nIxA5426 TIMING_REP_OR_STOP = [ TRUE ; FALSE ]\n\nO1A42\nO1A423\nO1A4238\nO1A431\nO2A431\nO2A432\nI1A43\nI1A431\nI1A432\nI1A433\n\nTRANSLATION_PAIR = LMF_PAIR\n\nTRANSMIT_CONTROL_CHAR = [REPLY_CHAR;CANCEL_CHAR; ENQUIRY_CHAR]\n\nTRIP = [N;C;O;P;R;D]\nTTY MESSAGE = JANAP_HEADER + SEPARATOR + BODY + SEPARATOR + JANAP_TRAILER\n\n* NOTE: THE MAXIMUM LENGTH FOR A PHYSICAL LINE IN A TTY MESSAGE IS 69 PRINTABLE CHARACTERS. SINCE A FORMAT LINE MAY EXCEED THIS NUMBER, LN END'S MUST BE ADDED AS REQUIRED TO KEEP EACH PHYSICAL LINE AT OR BELOW THIS LENGTH *\n\n03A332 VALIDATED_MESSAGE = MESSAGE\n\n03A333\n03A334\n03A335\n03A3324\n03A3325\n03A3334\n03A3345\n03A3346\n03A3354\n\nYEAR = <2>(DIGIT)\nMessage Switch Non-Functional Requirements\n\nI. Messages shall be accepted without regard to the immediate availability of an outgoing line or trunk. The receive module will have the ability of throttling incoming traffic during overload periods or during periods of high priority messages. Two types of message codes will be handled.\n\nA. ASCII Code\n\n(1) Odd parity\n(2) Seven (7) bits plus parity\n(3) One (1) start unit interval\n(4) One (1) or two (2) stop unit interval(s)\n\nB. ITA #2 Code\n\n(1) 5 bits data\n(2) One (1) start unit interval\n(3) One (1) or two (2) stop unit interval(s)\n\nII. Synchronous Operation - Messages Received From an Autodin Switch\n\nA. Block-by-Block\n\n(1) 75-16000 b/s\n(2) ASCII character set\n(3) Parity Criteria - (7 bits for information and the 8th bit for parity)\n(4) Bits received serially - (low order bit first and the parity bit last)\n(5) Message characters will have odd parity\n(6) Control characters will have even parity\n(7) Modes I or III\n(8) Acquire frame sync. before receive\n(9) A message control block (MCB) will be employed if the message is via an interswitch trunk\n(10) Bit stream - bit synchronous where each bit is accompanied with a clock pulse\n(11) Recognize accepted idle pattern for channel sync.\n(12) SOH/STX characters of a block stream will be separated by a syn. period from the previous block.\nb. Continuous (block-by-block)\n\n(1) SOH/STX characters of a block stream will be contiguous to the block parity character of the previous block.\n\n(2) Reception of continuous (block-by-block) is the same as block-by-block above except for item 12.\n\nIII. Asynchronous Operations Modes II, IV (without Automatic Channel and Error Control)\n\nA. ASCII and ITA#2 Codes (Mode II)\n\n(1) Free running characters\n\n(2) Character by character release\n\n(3) Independent of simultaneous two-way operation\n\nB. ASCII and ITA#2 Code (Mode IV)\n\n(1) Unidirectional operation (send only or receive only)\n\n(2) Equivalent to half duplex operation of Mode II\n\n(3) Free running characters\n\nIV. Asynchronous Operation Mode V (with automatic channel and error control)\n\nA. ASCII Code\n\n(1) 75-300 baud\n\n(2) Continuous two-way transmission\n\nB. ITA #2 Code\n\n(1) 45.45 to 75 baud\n\n(2) Continuous two-way transmission\n\nV. Message statistics. The maximum length message is 44,000 characters (or 550 blocks). The maximum length teletype (TTY) message is 6900 characters. The average message length is 2400 characters. There will be an average of 1.75 addresses per message. The average collective RI received will have 3.9 destinations. The messages will be distributed among the various precedences as follows:\n\n- ECP(Y)/CRITIC(W) 0.1%\n- FLASH(Z) 2.9%\n- IMMEDIATE(O) 30.0%\n- PRIORITY(P) 33.0%\n- ROUTINE(R) 34.0%\nVI. Maximum character handling - characters per time period\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>25 line switch</th>\n<th>50 line switch</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>1 second</td>\n<td>1 second</td>\n</tr>\n<tr>\n<td>Input</td>\n<td>3600</td>\n<td>5400</td>\n</tr>\n<tr>\n<td>Output</td>\n<td>2400</td>\n<td>3600</td>\n</tr>\n</tbody>\n</table>\n\nVII. Errors. Bit errors within the switch or delivered to output terminals shall not exceed 1 bit in 10 billion consecutive bits. No more than 1 message in 10 million messages shall be misrouted. No more than 1 in 10 million messages shall be lost due to nondetection or errors in the following: SOM, EOM, cancel transmission (CANTTRAN), or header. Loss of receipted messages shall not exceed 1 in 1 billion.\n\nVIII. Processing time. Processing time will be the sum of the time for reception of the EOM until the message is placed on the output queue and the time from the output line becoming available until the first bit of the SOM is transmitted. Mean processing time will be 2 seconds per message. No more than 1 in 1,000 CRITIC, ECP, or FLASH messages will have in processing time greater than 6 seconds. No more than 1 in 1,000 messages of lower precedence will have a processing time in excess of 8 seconds.\n\nIX. Routing table size. The routing table shall contain room for:\n\n- 1500 single address RIs\n- 200 collective RIs with an average 20 RIs each\n- 600 RIs for other centers\n\nX. Intransit storage size. For a 25 line switch, intransit storage shall be capable of holding a minimum of 2000 average length messages. For 50 lines this number shall be increased to 2500.\n\nXI. Recovery and retrieval. Reentry of messages from intercept storage shall be such that the first message is ready for reentry with 10 minutes of the reentry directive. Retrieval of CRITIC, ECP, and FLASH messages less than 24 hours old shall be accomplished in 7 minutes or less. All other messages less than 24 hours old shall be retrieved within 15 minutes. Messages older than 24 hours must be capable of being retrieved within 30 minutes.\nRecovery of messages after switch failure must take no more than 30 minutes."}}},{"rowIdx":88,"cells":{"id":{"kind":"string","value":"4f3618dc47deacb05f6fc4e8e607b1d5b3824e49"},"text":{"kind":"string","value":"LOCKSS System Manual\n\nLOCKSS Program\n\n2023-07-26\nThe LOCKSS system is a distributed digital preservation software system developed by the LOCKSS Program, a division of the Digital Library Systems and Services department at Stanford University Libraries.\n\nThe 2.x series of the LOCKSS system stems from the LAAWS (LOCKSS Architected As Web Services) initiative, an ambitious modernization project that includes rewriting the classic LOCKSS daemon as a suite of containerized components, funded in part by a grant from the Andrew W. Mellon Foundation.\n\nThis version, LOCKSS 2.0-alpha7, is the seventh \"alpha\" release of the LOCKSS system on the road to LOCKSS 2.0.\n\n1.1 System Prerequisites\n\n1.1.1 Host\n\nThe LOCKSS system runs in a 64-bit Linux host (physical or virtual).\n\nSee the next section (Operating System) for operating system choices.\n\n1.1.2 CPU\n\nThe CPU requirements depend on which components of the LOCKSS system you choose to run. We recommend at least 4 CPU cores, preferably 8.\n\n1.1.3 Memory\n\nLikewise, the memory requirements also depend on which components of the LOCKSS system you choose to run. We recommend at least 16 GB of memory, preferably more.\n\n1.1.4 Storage\n\nLOCKSS makes use of several storage areas. During configuration, the administrator must specify the location of these storage areas by supplying one or more directory paths. The default is to put all storage under a single directory, but different types of storage have different size and performance requirements and on a large system, if different types of storage are available it may be advantageous to place the storage areas on different devices:\n\n- **Content data storage:** This is where all the preserved content is stored, along with an index and several databases. Many LOCKSS systems preserve a large amount of content and it has become common to use network-attached storage for this. LOCKSS' audit activities result in nearly continuous reading of content from\n\n---\n\n1 Unless using external Solr and/or PostgreSQL servers.\nstorage; this may impact the storage server’s performance, and a busy or non-performant storage server may impact LOCKSS’ performance. For the repository service, multiple storage areas may be specified, and more can be added later.\n\nThe amount of space required depends on the amount of content that will be preserved. The content is efficiently stored in large, compressed WARC files. Unlike LOCKSS 1.x, inode usage is very low.\n\n- **Log data storage**: Service logs will be written to subdirectories of this path. There is usually no reason to enter a different path unless you have specific logging requirements.\n\n- **Temporary data storage**: The LOCKSS software makes heavy use of temporary storage, and we recommend that temporary directories be placed on a filesystem with relatively low latency. If the content storage directories are on network storage (for example NFS), system performance may be improved by using a local directory.\n\n**Caution**: Depending on the characteristics of the preservation activities undertaken by the system, in some circumstances content processing may require a substantial amount of temporary space, up to tens of gigabytes. Do not use a RAM-based tmpfs volume, or a directory in a space-constrained partition, for temporary data storage.\n\n---\n\n**What's the Minimum for Experimentation?**\n\nTo review the installation instructions and test the installation of K3s in various operating systems, we routinely install and bring up minimal LOCKSS 2.0-alpha5 systems, with no metadata services or Web replay engines, and with empty embedded Postgres and Solr databases, in Vagrant virtual machines with Virtualbox using 2 CPU cores and 3 GB of memory. These minimal VMs would not support a production load, but it can be a useful tool to try out the installation instructions or evaluate the system.\n\n---\n\n### 1.2 Operating System\n\nThe LOCKSS system requires a **64-bit Linux** host (physical or virtual) compatible with K3s, a lightweight Kubernetes distribution by Rancher. The K3s documentation states\\(^1\\) that \"K3s is expected to work on most modern Linux systems\", and that \"Some OSs have specific requirements\" (which are documented in this manual and integrated into the lockss-installer scripts).\n\nThe LOCKSS team has successfully tested the LOCKSS system installation process on many flavors of Linux, some of which are listed below:\n\n**AlmaLinux OS**\n\nThe LOCKSS system is compatible with AlmaLinux OS:\n\n---\n\n\\(^1\\) Reference: [https://docs.k3s.io/installation/requirements#operating-systems](https://docs.k3s.io/installation/requirements#operating-systems)\nArch Linux\n\nThe LOCKSS system is compatible with Arch Linux:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Arch Linux</td>\n<td></td>\n<td></td>\n<td></td>\n<td>rolling release</td>\n</tr>\n</tbody>\n</table>\n\nCentOS\n\nCaution: We no longer recommend CentOS for new installations; we recommend Rocky Linux instead.\n\nThe LOCKSS system is compatible with CentOS:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CentOS Stream</td>\n<td></td>\n<td></td>\n<td></td>\n<td>rolling release</td>\n</tr>\n<tr>\n<td>CentOS Linux</td>\n<td>7.9</td>\n<td>2020-08-06</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>CentOS Linux</td>\n<td>7.8</td>\n<td>2020-08-06</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>CentOS Linux</td>\n<td>7.7</td>\n<td>2020-08-06</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>CentOS Linux</td>\n<td>7.6</td>\n<td>2020-08-06</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>CentOS Linux</td>\n<td>7.5</td>\n<td>2020-08-06</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>CentOS Linux</td>\n<td>7.4</td>\n<td>2020-08-06</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>CentOS Linux</td>\n<td>7.3</td>\n<td>2020-08-06</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n</tbody>\n</table>\n### Debian\n\nThe LOCKSS system is compatible with **Debian**:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Debian</td>\n<td>11.6</td>\n<td>2024-07-01</td>\n<td>2026-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>11.5</td>\n<td>2024-07-01</td>\n<td>2026-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>11.4</td>\n<td>2024-07-01</td>\n<td>2026-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>11.3</td>\n<td>2024-07-01</td>\n<td>2026-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>11.2</td>\n<td>2024-07-01</td>\n<td>2026-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>11.1</td>\n<td>2024-07-01</td>\n<td>2026-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>11.0</td>\n<td>2024-07-01</td>\n<td>2026-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.13</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.12</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.11</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.10</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.9</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.8</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.7</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.6</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.5</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.4</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.3</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.2</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.1</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Debian</td>\n<td>10.0</td>\n<td>2022-09-10</td>\n<td>2024-06-30</td>\n<td>end of life</td>\n</tr>\n</tbody>\n</table>\n\n### EuroLinux\n\nThe LOCKSS system is compatible with **EuroLinux**:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EuroLinux</td>\n<td>9.1</td>\n<td>2032-05-31</td>\n<td>2032-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>EuroLinux</td>\n<td>9.0</td>\n<td>2032-05-31</td>\n<td>2032-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>EuroLinux</td>\n<td>8.6</td>\n<td>2029-03-01</td>\n<td>2029-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>EuroLinux</td>\n<td>8.5</td>\n<td>2029-03-01</td>\n<td>2029-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>EuroLinux</td>\n<td>8.4</td>\n<td>2029-03-01</td>\n<td>2029-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>EuroLinux</td>\n<td>8.3</td>\n<td>2029-03-01</td>\n<td>2029-06-30</td>\n<td></td>\n</tr>\n<tr>\n<td>EuroLinux</td>\n<td>7.9</td>\n<td>2024-07-31</td>\n<td>2024-07-31</td>\n<td></td>\n</tr>\n<tr>\n<td>EuroLinux</td>\n<td>7.8</td>\n<td>2024-07-31</td>\n<td>2024-07-31</td>\n<td></td>\n</tr>\n<tr>\n<td>EuroLinux</td>\n<td>7.7</td>\n<td>2024-07-31</td>\n<td>2024-07-31</td>\n<td></td>\n</tr>\n<tr>\n<td>EuroLinux</td>\n<td>7.6</td>\n<td>2024-07-31</td>\n<td>2024-07-31</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nFedora Linux\n\nThe LOCKSS system is compatible with Fedora Linux:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Fedora Linux</td>\n<td>37</td>\n<td>2023-12-15</td>\n<td>2023-12-15</td>\n<td></td>\n</tr>\n<tr>\n<td>Fedora Linux</td>\n<td>36</td>\n<td>2023-05-16</td>\n<td>2023-05-16</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nLinux Mint\n\nThe LOCKSS system is compatible with Linux Mint:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Linux Mint</td>\n<td>21</td>\n<td>Yes</td>\n<td>2027-04-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Linux Mint</td>\n<td>20.3</td>\n<td>Yes</td>\n<td>2025-04-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Linux Mint</td>\n<td>20.2</td>\n<td>Yes</td>\n<td>2025-04-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Linux Mint</td>\n<td>20.1</td>\n<td>No</td>\n<td>2025-04-01</td>\n<td>end of life</td>\n</tr>\n<tr>\n<td>Linux Mint</td>\n<td>20</td>\n<td>No</td>\n<td>2025-04-01</td>\n<td>end of life</td>\n</tr>\n</tbody>\n</table>\n\nOpenSUSE\n\nThe LOCKSS system is compatible with OpenSUSE:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>OpenSUSE Tumbleweed</td>\n<td>rolling release</td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>OpenSUSE Leap</td>\n<td>15.4</td>\n<td>2023-12-01</td>\n<td>2023-12-01</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nOracle Linux\n\nThe LOCKSS system is compatible with Oracle Linux:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Oracle Linux</td>\n<td>9.1</td>\n<td>2032-07-01</td>\n<td>2034-06-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>9.0</td>\n<td>2032-07-01</td>\n<td>2034-06-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>8.7</td>\n<td>2029-07-01</td>\n<td>2029-07-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>8.6</td>\n<td>2029-07-01</td>\n<td>2029-07-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>8.5</td>\n<td>2029-07-01</td>\n<td>2029-07-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>8.4</td>\n<td>2029-07-01</td>\n<td>2029-07-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>8.3</td>\n<td>2029-07-01</td>\n<td>2029-07-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>8.2</td>\n<td>2029-07-01</td>\n<td>2029-07-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>8.1</td>\n<td>2029-07-01</td>\n<td>2029-07-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>7.9</td>\n<td>2024-07-01</td>\n<td>2026-06-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>7.8</td>\n<td>2024-07-01</td>\n<td>2026-06-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>7.7</td>\n<td>2024-07-01</td>\n<td>2026-06-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Oracle Linux</td>\n<td>7.6</td>\n<td>2024-07-01</td>\n<td>2026-06-01</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nThe LOCKSS system is compatible with **RHEL**:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>RHEL</td>\n<td>8.3</td>\n<td>2024-05-31</td>\n<td>2029-05-31</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**Tip:** Rocky Linux is the operating system we currently recommend for new installations, and for existing installations based on CentOS or Scientific Linux.\n\nThe LOCKSS system is compatible with **Rocky Linux**:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Rocky Linux</td>\n<td>9.1</td>\n<td>2025-05-31</td>\n<td>2032-05-31</td>\n<td></td>\n</tr>\n<tr>\n<td>Rocky Linux</td>\n<td>9.0</td>\n<td>2025-05-31</td>\n<td>2032-05-31</td>\n<td></td>\n</tr>\n<tr>\n<td>Rocky Linux</td>\n<td>8.7</td>\n<td>2024-05-31</td>\n<td>2029-05-31</td>\n<td></td>\n</tr>\n<tr>\n<td>Rocky Linux</td>\n<td>8.6</td>\n<td>2024-05-31</td>\n<td>2029-05-31</td>\n<td></td>\n</tr>\n<tr>\n<td>Rocky Linux</td>\n<td>8.5</td>\n<td>2024-05-31</td>\n<td>2029-05-31</td>\n<td></td>\n</tr>\n<tr>\n<td>Rocky Linux</td>\n<td>8.4</td>\n<td>2024-05-31</td>\n<td>2029-05-31</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n**Caution:** We no longer recommend Scientific Linux for new installations; we recommend Rocky Linux instead.\n\nThe LOCKSS system is compatible with **Scientific Linux**:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Scientific Linux</td>\n<td>7.9</td>\n<td>2024-06-30</td>\n<td>2024-06-30</td>\n<td>obsolescent</td>\n</tr>\n<tr>\n<td>Scientific Linux</td>\n<td>7.8</td>\n<td>2024-06-30</td>\n<td>2024-06-30</td>\n<td>obsolescent</td>\n</tr>\n<tr>\n<td>Scientific Linux</td>\n<td>7.7</td>\n<td>2024-06-30</td>\n<td>2024-06-30</td>\n<td>obsolescent</td>\n</tr>\n<tr>\n<td>Scientific Linux</td>\n<td>7.6</td>\n<td>2024-06-30</td>\n<td>2024-06-30</td>\n<td>obsolescent</td>\n</tr>\n</tbody>\n</table>\n\n**Ubuntu**\n\nThe LOCKSS system is compatible with **Ubuntu**:\n\n<table>\n<thead>\n<tr>\n<th>Operating System</th>\n<th>Version</th>\n<th>Active Support</th>\n<th>Security Support</th>\n<th>Notes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Ubuntu</td>\n<td>22.10</td>\n<td>2023-07-20</td>\n<td>2023-07-20</td>\n<td></td>\n</tr>\n<tr>\n<td>Ubuntu</td>\n<td>22.04 LTS</td>\n<td>2027-04-21</td>\n<td>2032-04-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Ubuntu</td>\n<td>20.04 LTS</td>\n<td>2025-04-02</td>\n<td>2030-04-01</td>\n<td></td>\n</tr>\n<tr>\n<td>Ubuntu</td>\n<td>18.04 LTS</td>\n<td>2023-04-02</td>\n<td>2028-04-01</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nThe LOCKSS system can likely be installed successfully on slightly different versions of the Linux flavors above, as well as other Linux flavors altogether, including commercial variants like RHEL or SLES. We welcome reports of successful installations from the community so they can be added to the list above.\n\n**Tip:** Rocky Linux is the operating system we currently recommend for new installations, and for existing installations based on CentOS or Scientific Linux.\nCHAPTER TWO\n\nUPGRADING FROM LOCKSS 2.0-ALPHA6\n\nNote: This chapter describes how to upgrade an existing LOCKSS 2.0-alpha6 system to 2.0-alpha7. If you are installing the LOCKSS 2.x system for the first time, please see the installation instructions in the next chapter: \n\nInstalling the LOCKSS System\n\nTip: Before you begin the upgrade, we strongly recommend you first bring your operating system up to date by applying security updates and upgrading installed packages. Ask your system administrator or see Operating System Updates in the appendix.\n\nNote: Commands in this section are run as the lockss user\\(^1\\).\n\n2.1 Stop LOCKSS 2.0-alpha6\n\nThe first step is to stop the LOCKSS 2.0-alpha6 system. Log in as the lockss user and run the following command in the LOCKSS Installer Directory:\n\n```bash\nscripts/stop-lockss\n```\n\nYou may verify all LOCKSS components have stopped by running the following command:\n\n```bash\nk3s kubectl get deployments -n lockss\n```\n\nwhich should return:\n\n```\nNo resources found in lockss namespace.\n```\n\n\\(^1\\) See Running Commands as the lockss User.\n2.2 Update the LOCKSS Installer\n\nAs of 2.0-alpha5, the official way to install and upgrade the LOCKSS Installer is using the LOCKSS Downloader, rather than cloning the LOCKSS Installer as a Git project. The instructions below detail the use of the LOCKSS Downloader. (Advanced users may continue to use **git** if they wish; please see *Downloading the LOCKSS Installer using git* for instructions.)\n\nAs the **lockss** user, run either this **curl** command:\n\n```\ncurl -sSfL https://lockss.org/downloader | sh -s -\n```\n\nOr this **wget** command:\n\n```\nwget -qO- https://lockss.org/downloader | sh -s -\n```\n\nThis will download and invoke the LOCKSS Downloader, which in turn will install the latest version of the LOCKSS Installer into the default LOCKSS Installer Directory (**$HOME/lockss-installer**). If you are using a custom LOCKSS Installer Directory **DIR**, remember to use **--download-dir=DIR**; see *Running the LOCKSS Downloader* for details.\n\n2.3 Run the Upgrade Script\n\nFIXME (this section is likely different for beta1)\n\nThe next step is to update archived content from the previous release version. As the **lockss** user, run the following command in the **LOCKSS Installer Directory**:\n\n```\nscripts/upgrades/upgrade-to-alpha6\n```\n\n**Hint**: If it takes more than a few seconds for **upgrade-to-alpha6** above to run, the reindexing of all previously archived content which occurs the first time you start 2.0-alpha6 after upgrading from 2.0-alpha5 may take prohibitively long. This performance issue will be addressed in the next release. If you do not need the previously stored content during alpha testing, you could delete it and skip this reindexing step; see *Resetting the System to a Blank State*.\n\n2.4 Re-run the Configure Script\n\nRe-run the configuration script by running the command below and follow the instructions in *Configuring the LOCKSS System* to ensure all existing configuration parameters are still correct and to configure any new parameters:\n\n```\nscripts/configure-lockss\n```\n2.5 Start LOCKSS 2.0-alpha6\n\nFollow the instructions in *Running the LOCKSS System* to start your LOCKSS 2.0-alpha7 instance:\n\n```\nscripts/start-lockss\n```\n\n**Hint:** If it takes more than a few seconds for `upgrade-to-alpha6` above to run, the reindexing of all previously archived content which occurs the first time you start 2.0-alpha6 after upgrading from 2.0-alpha5 may take prohibitively long. This performance issue will be addressed in the next release. If you do not need the previously stored content during alpha testing, you could delete it and skip this reindexing step; see *Resetting the System to a Blank State.*\nCHAPTER\nTHREE\n\nINSTALLING THE LOCKSS SYSTEM\n\nNote: This chapter describes how to install the LOCKSS 2.0-alpha7 system from scratch. If you are upgrading an existing LOCKSS 2.0-alpha6 system to 2.0-alpha7, please see the upgrade instructions in the previous chapter: Upgrading From LOCKSS 2.0-alpha6\n\nTip: Before you begin installing the LOCKSS system, we strongly recommend you first bring your operating system up to date by applying security updates and upgrading installed packages. Ask your system administrator or see Operating System Updates.\n\nThis chapter describes how to install the LOCKSS system from scratch.\n\n3.1 Creating the lockss User\n\nNote: Commands in this section are run as root.\n\nThe first task is to create a system user named lockss, under which the LOCKSS system will run.\n\nRun this useradd command as root:\n\n```\nuseradd --system --user-group --create-home --shell=/bin/bash lockss\n```\n\nor equivalently:\n\n```\nuseradd -rUs /bin/bash lockss\n```\n\nThis will create a lockss system user, a lockss system group, and a home directory in /home/lockss.\n\n1 See Running Commands as root.\n3.2 Downloading the LOCKSS Installer\n\nNote: Commands in this section are run as the lockss user\\(^1\\).\n\nThe next task is to download the LOCKSS Installer.\n\n### 3.2.1 LOCKSS Installer Directory\n\nThe directory into which the LOCKSS Installer is downloaded is simply known as the **LOCKSS Installer Directory**. Many commands in this manual, such as those to install, configure, start and stop the LOCKSS system, are relative to the LOCKSS Installer Directory, meaning you need to navigate to it at the console before issuing the relevant command.\n\n### 3.2.2 Default LOCKSS Installer Directory\n\nUnless you use the LOCKSS Downloader's `--download-dir` option to set a custom LOCKSS Installer Directory, the **default LOCKSS Installer Directory** will be `${HOME}/lockss-installer`, where `${HOME}` refers to the lockss user's home directory.\n\n### 3.2.3 Running the LOCKSS Downloader\n\nTo download the LOCKSS Installer, you will use **Curl**, **Wget** or **HTTPie**\\(^2\\) to invoke the **LOCKSS Downloader**\\(^3\\), whose default action is to download the LOCKSS Installer.\n\nAs the lockss user\\(^1\\), run this Curl, Wget or HTTPie command\\(^2\\):\n\n**Curl**\n\n```\ncurl -sSfL https://lockss.org/downloader | sh -s -\n```\n\n**HTTPie**\n\n```\nhttp -qd https://lockss.org/downloader | sh -s -\n```\n\n---\n\n1. See *Running Commands as the lockss User*.\n2. Most typical Linux systems have at least one of Curl, Wget or HTTPie installed by default. You can check by typing `curl --version`, `wget --version` or `http --version`, and seeing which ones do not output an error message. See *Installing Curl*, *Installing Wget* or *Installing HTTPie* for installation instructions.\n3. The LOCKSS Downloader is a script to download GitHub projects without Git, with Curl, Wget or HTTPie instead. See [https://github.com/lockss/lockss-downloader](https://github.com/lockss/lockss-downloader).\nWget\n\n```\nwget -qO- https://lockss.org/downloader | sh -s -\n```\n\nThis will download the LOCKSS Installer into the Default LOCKSS Installer Directory.\n\n**Tip:** Below are some advanced tips for this section.\n\n### Inspecting the LOCKSS Downloader before running it\n\nFor security purposes, you may wish to inspect the LOCKSS Downloader before executing it.\n\nOne option is to review the contents of the script directly on GitHub to your satisfaction, then execute it as described above. The URL [https://lockss.org/downloader](https://lockss.org/downloader) redirects to [https://github.com/lockss/lockss-downloader/raw/main/lockss-downloader](https://github.com/lockss/lockss-downloader/raw/main/lockss-downloader).\n\nAnother option is to download a copy of the LOCKSS Downloader script, review it, then execute it, all locally. To do so, follow this procedure:\n\n1. As the lockss user\\(^1\\), run this Curl, Wget or HTTPie command\\(^2\\):\n\n **Curl**\n\n ```\ncurl -Lo lockss-downloader https://lockss.org/downloader\n ```\n\n **HTTPie**\n\n ```\n http -qdo lockss-downloader https://lockss.org/downloader\n ```\n\n **Wget**\n\n ```\n wget -qO lockss-downloader https://lockss.org/downloader\n ```\n\n This will download the LOCKSS Downloader script into the current directory as `lockss-downloader`.\n\n2. Inspect the file `lockss-downloader` to your satisfaction.\n\n3. Run this command:\n\n ```\n chmod +x lockss-downloader\n ```\n\n to make the LOCKSS Downloader script executable.\n\n4. Type:\n\n ```\n ./lockss-downloader\n ```\n\n to run the LOCKSS Downloader script. You can append to `./lockss-downloader` all the same options that can be appended to `| sh -s -` in the normal procedure documented in this section, for instance `./lockss-downloader --download-dir=DIR`.\n\n3.2. Downloading the LOCKSS Installer\nCustom LOCKSS Installer Directory\n\nIf you need your LOCKSS Installer Directory to be a directory DIR other than the Default LOCKSS Installer Directory, add --download-dir=DIR (or -d DIR) after | sh -s -, like so:\n\n```\n... | sh -s --download-dir=DIR\n```\n\nCustom version of the LOCKSS Installer\n\nIf you have a reason to install a version of the LOCKSS Installer other than the latest stable release 2.0.70-alpha7, you can do so by making references to the lockss-installer Git repository on GitHub:\n\n- You can install a version from the tip of a given branch BRA of the lockss-installer Git repository (e.g. develop) by adding --git-branch=BRA (or -b BRA) after | sh -s -. This might be needed if you are helping the LOCKSS Team test a development, pre-release, or hotfix version of the LOCKSS Installer.\n\n- You can install a version labeled by a given tag TAG of the lockss-installer Git repository (e.g. version-2.0.61-alpha6) by adding --git-tag=TAG (or -t TAG) after | sh -s -. This might be needed if you are installing a specific past version of the LOCKSS Installer.\n\n- You can install a version as of a specific commit identifier COM of the lockss-installer Git repository by adding --git-commit=COM (or -c COM) after | sh -s -. This might be needed if you are helping the LOCKSS Team test a development version of the LOCKSS Installer.\n\nConsiderations if using sudo -u\n\nIf you must use:\n\n```\n... | sudo -u lockss sh -s -\n```\n\nto invoke the LOCKSS Downloader as the lockss user, beware that typically it will run in a context where ${HOME} has been adjusted to the home directory of the lockss user, but this is not guaranteed -- it depends on the way sudo is configured on your host system. To ensure ${HOME} is set correctly, use the -H (--set-home) option of sudo, for example like so:\n\n```\n... | sudo -Hu lockss sh -s -\n```\n\n3.3 Running the LOCKSS Installer\n\nNote: Commands in this section are run as root.\n\nThe next task is to run the LOCKSS Installer.\n\nThe installation process goes through various phases:\n\n- Checking that some prerequisites to install K3s are met. No user interaction is expected.\n\n---\n\n4 See https://github.com/lockss/lockss-installer.\n1 See Running Commands as root.\n• Checking that the lockss system user and group exist. No user interaction is expected.\n\n• Configuring `iptables`, `firewalld` and `ufw` for K3s. If applicable, you will be prompted to confirm before your system configuration is modified. You may incidentally be prompted for your `sudo` password.\n\n• Configuring CoreDNS for K3s. If applicable, you will be prompted to enter non-loopback IP addresses of DNS servers.\n\n• Installing K3s. If applicable, you will be prompted for a Kubernetes state data storage directory.\n\n• Testing the K3s node. No user interaction is expected.\n\nAfter the LOCKSS Installer succeeds, you can also optionally run the K3s Configuration Checker.\n\n### 3.3.1 Invoking the LOCKSS Installer\n\nTo start the installation process, run this command (relative to the LOCKSS Installer Directory) as `root`:\n\n```\nscripts/install-lockss\n```\n\nThe installer will run through its phases, each of which is described in its own section below from Checking K3s Prerequisites (Section 3.3.2) to Completion of the LOCKSS Installation Process (Section 3.3.10).\n\n**Tip:** Below are some advanced tips for this section.\n\n#### Skipping install-lockss phases\n\nYou may need to skip some of the phases of `install-lockss`, for example to overcome an incompatibility with the specifics of your host system. If this is necessary, invoke `install-lockss` with one or more of the following options:\n\n<table>\n<thead>\n<tr>\n<th>Option</th>\n<th>Phase(s) skipped</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>--skip-check-prerequisites</code></td>\n<td>Checking K3s Prerequisites (Section 3.3.2)</td>\n</tr>\n<tr>\n<td><code>--skip-check-system-user</code></td>\n<td>Checking the System User and Group (Section 3.3.3)</td>\n</tr>\n<tr>\n<td><code>--skip-configure-iptables</code></td>\n<td>Configuring iptables for K3s (Section 3.3.4)</td>\n</tr>\n<tr>\n<td><code>--skip-configure-firewalld</code></td>\n<td>Configuring firewalld for K3s (Section 3.3.5)</td>\n</tr>\n<tr>\n<td><code>--skip-configure-ufw</code></td>\n<td>Configuring ufw for K3s (Section 3.3.6)</td>\n</tr>\n<tr>\n<td><code>--skip-configure-coredns</code></td>\n<td>Configuring CoreDNS for K3s (Section 3.3.7)</td>\n</tr>\n<tr>\n<td><code>--skip-install-k3s</code></td>\n<td>• Checking K3s Prerequisites (Section 3.3.2)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Configuring iptables for K3s (Section 3.3.4)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Configuring firewalld for K3s (Section 3.3.5)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Configuring ufw for K3s (Section 3.3.6)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Configuring CoreDNS for K3s (Section 3.3.7)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Installing K3s (Section 3.3.8)</td>\n</tr>\n<tr>\n<td><code>--skip-test-k3s</code></td>\n<td>Testing the K3s Node (Section 3.3.9)</td>\n</tr>\n</tbody>\n</table>\n\nWhen a phase is skipped as a result of one of these options, you will see a message similar to this during the corresponding phase:\n\n```\n[success] Skipping (--skip-configure-firewalld)\n```\nRunning only one `install-lockss` phase\n\nConversely, you may need to run or re-run only one phase of `install-lockss`, for example re-running the *Testing the K3s Node* phase after it fails and you perform some troubleshooting. If this is necessary, invoke `install-lockss` with exactly one of the following options:\n\n<table>\n<thead>\n<tr>\n<th>Option</th>\n<th>Phase executed</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>--check-prerequisites</code> (or <code>-P</code>)</td>\n<td>Checking K3s Prerequisites (Section 3.3.2)</td>\n</tr>\n<tr>\n<td><code>--check-system-user</code> (or <code>-L</code>)</td>\n<td>Checking the System User and Group (Section 3.3.3)</td>\n</tr>\n<tr>\n<td><code>--configure-iptables</code> (or <code>-I</code>)</td>\n<td>Configuring iptables for K3s (Section 3.3.4)</td>\n</tr>\n<tr>\n<td><code>--configure-firewalld</code> (or <code>-F</code>)</td>\n<td>Configuring firewalld for K3s (Section 3.3.5)</td>\n</tr>\n<tr>\n<td><code>--configure-ufw</code> (or <code>-U</code>)</td>\n<td>Configuring ufw for K3s (Section 3.3.6)</td>\n</tr>\n<tr>\n<td><code>--configure-coredns</code> (or <code>-C</code>)</td>\n<td>Configuring CoreDNS for K3s (Section 3.3.7)</td>\n</tr>\n<tr>\n<td><code>--install-k3s</code> (or <code>-K</code>)</td>\n<td>Installing K3s (Section 3.3.8)</td>\n</tr>\n<tr>\n<td><code>--test-k3s</code> (or <code>-T</code>)</td>\n<td>Testing the K3s Node (Section 3.3.9)</td>\n</tr>\n</tbody>\n</table>\n\nRunning `install-lockss` on auto-pilot\n\nIf you invoke `install-lockss` with the `--assume-yes` (or `-y`) option, it will attempt to run without asking any questions interactively, by assuming that the answer to any yes/no question is \"yes\" and that the answer to other interactive questions is the suggested default value. **This is only appropriate for advanced users** who understand the implications of the default code paths in *Configuring iptables for K3s* (Section 3.3.4), *Configuring firewalld for K3s* (Section 3.3.5), *Configuring ufw for K3s* (Section 3.3.6), *Configuring CoreDNS for K3s* (Section 3.3.7) and *Installing K3s* (Section 3.3.8) on the host system, for example after previous experience installing the LOCKSS system.\n\n3.3.2 Checking K3s Prerequisites\n\nDuring this phase, `install-lockss` will check that certain prerequisites to installing K3s are met. This phase begins with this heading:\n\nChecking K3s prerequisites...\n\nNo user interaction is expected; if everything goes well, you will see this message:\n\n[success] K3s prerequisites checked\n\nand `install-lockss` will successfully proceed to the next phase, *Checking the System User and Group* (Section 3.3.3).\n\n**Error:** Below are some error conditions you may encounter here and what to do about them.\n\n**User namespaces must be enabled in RHEL/CentOS 7**\n\nIn some RHEL 7 and CentOS 7 systems, user namespaces are not enabled by default. If this is the case, you will see the error message:\n\n[ERROR] User namespaces must be enabled in RHEL/CentOS 7; see manual\n\nand `install-lockss` will fail. See *Enabling User Namespaces in RHEL 7 and CentOS 7* for troubleshooting, then go back to *Invoking the LOCKSS Installer* to try again.\nApparmor enabled but apparmor_parser missing\n\nIn some systems, Apparmor is enabled but **apparmor_parser** is not installed. If this is the case, you will see the error message:\n\n```\n[ERROR] apparmor enabled but apparmor_parser missing; see manual\n```\n\nand **install-lockss** will fail. See *Installing apparmor_parser* for troubleshooting, then go back to *Invoking the LOCKSS Installer* to try again.\n\n### 3.3.3 Checking the System User and Group\n\nDuring this phase, **install-lockss** will check that the **lockss** user and group exist on the host system. This phase begins with the heading:\n\nChecking the system user and group...\n\nNo user interaction is expected; if everything goes well, you will see this message:\n\n```\n[success] System user and group present\n```\n\nand **install-lockss** will successfully proceed to the next phase, *Configuring iptables for K3s* (Section 3.3.4).\n\n**Error:** Below are some error conditions you may encounter here and what to do about them.\n\n**lockss user or group does not exist**\n\nIf the **lockss** user or group does not exist on the host system, you will see one of these error messages:\n\n```\n[ERROR] The lockss user does not exist\n```\n\n```\n[ERROR] The lockss group does not exist\n```\n\nand **install-lockss** will fail. Go back to the *Creating the lockss User* section to create the **lockss** user and group, then return to *Invoking the LOCKSS Installer* to try again.\n\n### 3.3.4 Configuring iptables for K3s\n\nDuring this phase, **install-lockss** will configure **iptables** to work with K3s, if applicable. This phase begins with the heading:\n\nConfiguring iptables for K3s...\n\nIn many situations, no configuration of **iptables** is needed; you will see one of these messages:\n\n```\n[success] Skipping (iptables is not on the PATH nor run via Alternatives)\n```\n\n```\n[success] Skipping (iptables version is older than 1.8.0)\n```\n\n```\n[success] Skipping (iptables version is newer than 1.8.3)\n```\n\n(continues on next page)\nand `install-lockss` will successfully proceed to the next phase, *Configuring firewalld for K3s* (Section 3.3.5).\n\nOtherwise, you will receive the following prompt:\n\n*Switch iptables to legacy mode via Alternatives?*\n\nEnter `Y` to accept the proposed `iptables` configuration, or enter `N` to bypass, or hit `Enter` to accept the default in square brackets². (You may be prompted for your `sudo` password.)\n\n---\n\n### Caution:\nIf you choose to bypass the proposed `iptables` configuration, you will see the warning:\n\n[Warning] Leaving iptables unchanged; see manual for details\n\nand `install-lockss` will keep going. But K3s may malfunction without further intervention; see *Troubleshooting iptables* for details.\n\n---\n\n### Error:\nBelow are some error conditions you may encounter here and what to do about them.\n\n#### iptables configuration attempt fails\n\nIf the `iptables` configuration attempt fails, you will see one of these error messages:\n\n- [ERROR] Error deactivating ufw\n- [ERROR] Error applying update-alternatives to iptables\n- [ERROR] Error applying update-alternatives to ip6tables\n- [ERROR] Error flushing iptables\n- [ERROR] Error reactivating ufw\n\nand `install-lockss` will fail. See *Troubleshooting iptables* for remediation details.\n\n---\n\n### 3.3.5 Configuring firewalld for K3s\n\nDuring this phase, `install-lockss` will configure `firewalld` to work with K3s, if applicable. This phase begins with the heading:\n\n*Configuring firewalld for K3s...*\n\nIn many situations, no configuration of `firewalld` is needed; you will see one of these messages:\n\n² If `install-lockss` was invoked with the `--assume-yes` option, `Y` is automatically entered for you.\nand **install-lockss** will successfully proceed to the next phase, *Configuring ufw for K3s* (Section 3.3.6).\n\nOtherwise, you will receive the following prompt:\n\n```\nAdd 10.42.0.0/16 and 10.43.0.0/16 to firewalld's trusted zone?\n```\n\nEnter `Y` to accept the proposed **firewalld** configuration, or enter `N` to bypass, or hit `Enter` to accept the default in square brackets. (You may be prompted for your `sudo` password.)\n\n---\n\n**Caution:** If you choose to bypass the proposed **firewalld** configuration, you will see the warning:\n\n```\n[Warning] Leaving firewalld unchanged; see manual for details\n```\n\nand **install-lockss** will keep going. But K3s may malfunction without further intervention; see *Troubleshooting firewalld* for details.\n\n---\n\n**Error:** Below are some error conditions you may encounter here and what to do about them.\n\n### firewalld configuration attempt fails\n\nIf the **firewalld** configuration attempt fails, you will see one of these error messages:\n\n- `[ERROR] Could not add 10.42.0.0/16 to firewalld's trusted zone`\n- `[ERROR] Could not add 10.43.0.0/16 to firewalld's trusted zone`\n- `[ERROR] Could not reload firewalld`\n\nand **install-lockss** will fail. See *Troubleshooting firewalld* for remediation details.\n\n---\n\n### 3.3.6 Configuring ufw for K3s\n\nDuring this phase, **install-lockss** will configure **ufw** to work with K3s, if necessary. This phase begins with the heading:\n\n```\nConfiguring ufw for K3s...\n```\n\nIn many situations, no configuration of **firewalld** is needed; you will see one of these messages:\n\n- `[success] Skipping (ufw is not on the PATH)`\n- `[success] Skipping (ufw is not active)`\n\nand **install-lockss** will successfully proceed to the next phase, *Configuring CoreDNS for K3s* (Section 3.3.7).\n\nOtherwise, you will receive the following prompt:\n\n```\nAllow traffic from 10.42.0.0/16 and 10.43.0.0/16 via ufw?\n```\nEnter Y to accept the proposed ufw configuration, or enter N to bypass, or hit Enter to accept the default in square brackets\\(^2\\). (You may be prompted for your sudo password.)\n\n<table>\n<thead>\n<tr>\n<th>Caution:</th>\n<th>If you choose to bypass the proposed ufw configuration, you will see the warning:</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>[Warning] Leaving ufw unchanged; see manual for details</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nand install-lockss will keep going. But K3s may malfunction without further intervention. See Troubleshooting ufw for details.\n\n<table>\n<thead>\n<tr>\n<th>Error:</th>\n<th>Below are some error conditions you may encounter here and what to do about them.</th>\n</tr>\n</thead>\n</table>\n\nufw configuration attempt fails\n\nIf the ufw configuration attempt fails, you will see one of these error messages:\n\n| [ERROR] Could not allow traffic from 10.42.0.0/16 via ufw |\n| [ERROR] Could not allow traffic from 10.43.0.0/16 via ufw |\n| [ERROR] Could not reload ufw |\n\nand install-lockss will fail. See Troubleshooting ufw for remediation details.\n\n3.3.7 Configuring CoreDNS for K3s\n\nDuring this phase, install-lockss will configure CoreDNS to work with K3s, if necessary. This phase begins with the heading:\n\nConfiguring CoreDNS for K3s...\n\nIn many situations, no configuration of firewalld is needed; you will see this message:\n\n| [success] Using system resolv.conf files |\n\nand install-lockss will successfully proceed to the next phase, Installing K3s (Section 3.3.8).\n\nOtherwise\\(^4\\), you will receive a message including CoreDNS does not allow a loopback address to be given to Kubernetes pods as an upstream DNS server, and the following prompt:\n\nIP address(es) of DNS resolvers, separated by ‘;’\n\nEnter a semicolon-separated list of DNS server IP addresses that are not loopback addresses. A suggested value will be offered to you in square brackets, consisting of non-loopback IP addresses collected from your machine's DNS configuration; you can simply hit Enter to accept the suggested value\\(^3\\).\n\n| Error: | Below are some error conditions you may encounter here and what to do about them. |\n\n\\(^2\\) Or if your install-lockss was invoked with the --force-dns-prompt option.\n\n\\(^3\\) If install-lockss was invoked with the --assume-yes option, the suggested value is automatically accepted for you.\nCoreDNS configuration attempt fails\n\nIf the CoreDNS configuration attempt fails, you will see one of these error messages:\n\n[ERROR] Could not create /etc/lockss\n\n[ERROR] Error rendering config/templates/k3s/resolv.conf.mustache to config/resolv.\n\n[ERROR] Could not copy config/resolv.conf to /etc/lockss/resolv.conf\n\nand install-lockss will fail. See Troubleshooting CoreDNS for remediation details.\n\n3.3.8 Installing K3s\n\nDuring this phase, install-lockss will install K3s 1.21.5+k3s1, if applicable. This phase begins with the heading:\n\nInstalling K3s...\n\nThis phase consists of these steps:\n\n1. First, install-lockss will determine if K3s 1.21.5+k3s1 needs to be installed:\n - If K3s is not present, install-lockss will display K3s is not present, and will install K3s 1.21.5+k3s1 in the next step.\n - If an older version of K3s is present, install-lockss will display Detected K3s version <installed_version> is older than expected version <expected_version>, and you will receive the following prompt:\n \n Upgrade K3s from <installed_version> to <expected_version>?\n \n Enter Y and install-lockss will install K3s 1.21.5+k3s1 in the next step, or enter N and install-lockss will not install K3s 1.21.5+k3s1 in the next step, or hit Enter to accept the default in square brackets.\n - If the expected version of K3s is already present, install-lockss will display K3s version <installed_version> is already installed; skipping, and will not install K3s 1.21.5+k3s1 in the next step.\n - If a more recent version of K3s is present, install-lockss will display Detected K3s version <installed_version> is more recent than expected version <expected_version>, and will not install K3s 1.21.5+k3s1 in the next step.\n - If K3s is detected but the installed and expected version numbers cannot be compared automatically, install-lockss will display [Warning] Detected K3s version <installed_version>, expected version <expected_version>, comparison failure, skipping, and install-lockss will not install K3s in the next step.\n\n2. If install-lockss determined in the previous step that it will not install K3s 1.21.5+k3s1, you will see the confirmation Not installing K3s, and nothing will happen in this step.\n\n But if install-lockss determined in the previous step that it will install K3s 1.21.5+k3s1, you will see the confirmation Installing K3s version <expected_version>, and this step will proceed as follows:\n - First, install-lockss will ask you to specify the K3s state data directory (the directory K3s uses to store state data), with this prompt:\n\n K3s state data directory\nBy default, this is `/var/lib/rancher/k3s`. However, if `/var` is space-limited, you should specify a different directory, that has ample space and is not backed by NFS or by XFS with legacy `ftype=0`.\n\nEnter a suitable directory path for the K3s state data directory, or hit Enter to accept the default in square brackets. Then `install-lockss` will attempt to determine the filesystem type of the specified K3s state data directory. In many situations, it will simply display the filesystem type in a message similar to this (for example, `<fs_type>` might be `ext4`):\n\nFilesystem type of `<k3s_dir>` (<`k3s_mountpoint`>) is `<fs_type>`; proceeding\n\n**Error:** Below are some error conditions you may encounter here and what to do about them.\n\n### Filesystem type of K3s state data directory is NFS\n\nIf the filesystem type backing the K3s state data directory is NFS, you will see the error message:\n\n```\n[ERROR] Filesystem type of `<k3s_dir>` (<`k3s_mountpoint`>) is NFS; see manual\n```\n\nand `install-lockss` will fail. It is not possible to run K3s with a state data directory backed by NFS. Re-run `install-lockss` and designate a different K3s state data directory that is not backed by NFS.\n\n### Filesystem type of K3s state data directory is XFS with legacy `ftype=0`\n\nIf the filesystem type backing the K3s state data directory is XFS with legacy `ftype=0`, you will see the error message:\n\n```\n[ERROR] Filesystem type of `<k3s_dir>` (<`k3s_mountpoint`>) is XFS with legacy `ftype=0`; see manual for workaround\n```\n\nand `install-lockss` will fail. Contemporary XFS filesystems with modern `ftype=1` work well with K3s, but older XFS filesystems with legacy `ftype=0` are not compatible. Ideally, re-run `install-lockss` and designate a different K3s state data directory that is not backed by XFS with legacy `ftype=0`. Alternatively, you can read about a workaround in *Troubleshooting OverlayFS with XFS*.\n\n**Warning:** Below are some warning messages you may see here and how to respond to them.\n\n### Filesystem type of K3s state data directory unknown\n\nIf the filesystem type backing the K3s state data directory cannot be inferred automatically, you will see the warning:\n\n```\n[Warning] Filesystem type of `<k3s_dir>` unknown (findmnt not present); proceeding\n```\n\nand `install-lockss` will keep going. But K3s may malfunction if the actual filesystem type backing the selected K3s state data directory is one that does not work with K3s, such as NFS, or XFS with legacy `ftype=0`; see the error conditions above.\n\n---\n\n5 If `install-lockss` was invoked with the `--k3s-data-dir=DIR` option, `DIR` will automatically be used without the prompt.\n\n6 See [https://github.com/containerd/containerd/discussions/6140](https://github.com/containerd/containerd/discussions/6140).\nFilesystem type of K3s state data directory is XFS but ftype unknown\n\nIf the ftype of the XFS filesystem backing the K3s state data directory cannot be inferred automatically, you will see the warning:\n\n[Warning] Filesystem type of k3s_dir (k3s_mountpoint) is XFS but ftype unknown (xfs_info not present); proceeding\n\nand install-lockss will keep going. But K3s may malfunction if the actual filesystem type backing the selected K3s state data directory is XFS with legacy ftype=0; see the corresponding error condition above.\n\nc. Then install-lockss will download the K3s Installer from https://get.k3s.io/ and invoke it with suitable options. This may take several minutes, during which the output to the console will be from the K3s Installer, not from install-lockss.\n\nDepending on your operating system and other factors, the K3s Installer may install additional software packages or configure system components, using sudo if necessary (which may prompt for the user's sudo password).\n\nError: If the K3s Installer does not succeed, it will display its own error messages, then install-lockss will fail. See Troubleshooting the K3s Installer for remediation details.\n\nSample error messages from the K3s Installer\n\nError messages that the K3s Installer may display include:\n\n```\n[ERROR] Failed to apply container_runtime_exec_t to /usr/local/bin/k3s,\n--- please install:\n yum install -y container-selinux selinux-policy-base\n k3s-selinux-0.3-0.el8.noarch.rpm\n```\n\n```\nError: Package: k3s-selinux-0.3-0.el7.noarch (rancher-k3s-common-stable)\n Requires: container-selinux >= 2.107-3\nYou could try using --skip-broken to work around the problem\nYou could try running: rpm -Va --nofiles --nodigest\n```\n\n3. Finally, whether or not K3s was installed, install-lockss will store Kubernetes configuration data as the lockss user in the file config/k8s.cfg (relative to the LOCKSS Installer Directory).\n\nError: Below are some error conditions you may encounter here and what to do about them.\n\n**Could not write or append to k8s.cfg**\n\nIf the creation of the file fails, you will see one of these error messages:\n\n```\n[ERROR] Could not write k8s.cfg\n\n[ERROR] Could not append to k8s.cfg\n```\nand `install-lockss` will fail. Check for file permission mismatches between the user running `install-lockss` and the `lockss-installer/config` directory, then try again.\n\n### 3.3.9 Testing the K3s Node\n\nDuring this phase, `install-lockss` runs a series of tests to verify that the K3s node is operational. This phase begins with the heading:\n\n**Testing the K3s node...**\n\nNo user interaction is expected. If all tests pass, you will see the message:\n\n```\n[success] Tested the K3s node\n```\n\nand `install-lockss` will successfully proceed to the next phase, *Completion of the LOCKSS Installation Process* (Section 3.3.10).\n\nOtherwise, you will see an error message corresponding to the test that did not pass, and `install-lockss` will fail.\n\n**Error:** Below are some error conditions you may encounter here and what to do about them.\n\n#### Problems with `config/k8s.cfg`\n\nAt the end of Section 3.3.8 (*Installing K3s*), some Kubernetes-related data is stored in `config/k8s.cfg` (relative to the *LOCKSS Installer Directory*). If the file cannot be found or read, or if it contains invalid or unexpected data, you may see one of these error messages:\n\n```\n[ERROR] k8s.cfg not found\n```\n\n```\n[ERROR] Error reading K8S_FLAVOR\n```\n\n```\n[ERROR] K8S_FLAVOR is not set\n```\n\n```\n[ERROR] K8S_FLAVOR is not k3s\n```\n\n```\n[ERROR] Error reading KUBECTL_CMD\n```\n\n```\n[ERROR] KUBECTL_CMD is not set\n```\n\n```\n[ERROR] k3s command of KUBECTL_CMD is not on the PATH\n```\n\nCheck the contents of `config/k8s.cfg` and contact us () for troubleshooting if necessary.\n\n#### Problems with the K3s node\n\nIf the K3s node is not behaving as expected, you may see one of these errors:\n\n```\n[ERROR] Command failed (kubectl version)\n```\n\n```\n[ERROR] Timeout waiting for the K3s node to be ready\n```\n\n```\n[ERROR] Command failed (kubectl get node)\n```\n\n```\n[ERROR] Unexpected number of K3s nodes\n```\n\nChapter 3. Installing the LOCKSS System\nIf the K3s node is newly installed, it may simply be that there has not yet been enough time for it to come up; you can re-run this phase with `scripts/install-lockss --test-k3s` (or `scripts/install-lockss -R`) to retry. Contact us () for troubleshooting if necessary.\n\n**Problems with DNS**\n\nIf the K3s node's DNS environment is not working properly, you may see one of these errors:\n\n- [ERROR] Timeout waiting for the CoreDNS pod to be running and ready\n- [ERROR] Command failed (kubectl get pod)\n- [ERROR] Unexpected number of CoreDNS pods\n- [ERROR] Timeout waiting for the DNS service to be present\n- [ERROR] Command failed (kubectl get service)\n- [ERROR] Unexpected number of kube-dns services\n- [ERROR] Unexpected kube-dns service type\n- [ERROR] Timeout waiting for DNS resolution\n- [ERROR] Unexpected Cluster-IP\n\nIf the K3s node is newly installed, it may simply be that there has not yet been enough time for CoreDNS to come up; you can re-run this phase with `scripts/install-lockss --test-k3s` (or `scripts/install-lockss -R`) to retry. You can also use the `install-lockss` options `--retries=N` (to increase the number of retries in DNS lookup tests to N from 5) or `--wait=S` (to increase the delay between retries in DNS lookup tests to S seconds from 10). Contact us () for troubleshooting if necessary.\n\n### 3.3.10 Completion of the LOCKSS Installation Process\n\nIf all phases completed successfully, you will see the message:\n\n```\n[success] Successful completion of the LOCKSS installation process\n```\n\nand `install-lockss` will terminate.\n\n### 3.3.11 Checking the K3s Configuration\n\n**Tip:** This section is optional.\n\nK3s comes with `k3s check-config`, a configuration checker tool. The K3s configuration checker is capable of detecting complex underlying system situations that definitely require fixing (or applications running in the K3s cluster will not be able to function properly). On the other hand, the versions of the K3s configuration checker available at the time LOCKSS 2.0-alpha7 was released contained bugs that reported spurious issues that are either inaccurate or moot. As a result, we have decided against running `k3s check-config` as part of `install-lockss` at this time, to avoid...\nunnecessary interruptions in the installation of the LOCKSS system in many cases where there is no particular cause for concern.\n\nThat being said, we still recommend running `k3s check-config` and interpreting the results using the Troubleshooting the K3s Configuration Checker section of the manual:\n\n1. Run this command:\n ```bash\n k3s check-config\n ```\n\n2. The following error messages in the output are indicative of system situations that require attention:\n ```plaintext\n /usr/sbin iptables v1.8.2 (nf_tables): should be older than v1.8.0, newer than v1.8.8-3, or in legacy mode (fail)\n RHEL7/CentOS7: User namespaces disabled; add 'user_namespace.enable=1' to boot command line (fail)\n apparmor: enabled, but apparmor_parser missing (fail)\n ```\n\n **Troubleshooting**\n See Troubleshooting the K3s Configuration Checker for details.\n\n3. The following error messages in the output can be ignored:\n ```plaintext\n cgroup hierarchy: nonexistent?? (fail)\n links: aux/ip6tables should link to iptables-detect.sh (fail)\n links: aux/ip6tables-restore should link to iptables-detect.sh (fail)\n links: aux/ip6tables-save should link to iptables-detect.sh (fail)\n links: aux/iptables should link to iptables-detect.sh (fail)\n links: aux/iptables-restore should link to iptables-detect.sh (fail)\n links: aux/iptables-save should link to iptables-detect.sh (fail)\n swap: should be disabled\n CONFIG_INET_XFRM_MODE_TRANSPORT: missing\n ```\n\n **Troubleshooting**\n See Troubleshooting the K3s Configuration Checker for details.\n\n4. For other error messages, check the official K3s documentation, search for K3s issues database on GitHub or the Web for resources matching your error message or operating system, and/or contact us so we can help investigate and document for future reference.\nAfter installing the LOCKSS system, you will configure it with the `configure-lockss` script. If you have experience with classic LOCKSS daemon version 1.x, this is the equivalent of `hostconfig`.\n\n### 4.1 Before Invoking `configure-lockss`\n\nYou will need to gather information to answer configuration questions asked by `configure-lockss`, including:\n\n- The name (FQDN) of the host.\n- The IP address of the host, and if behind NAT, the external IP address for NAT.\n- The mail relay host, and optionally mail credentials, for sending e-mail from the host.\n- The e-mail address for the administrator of the system.\n- The configuration URL and preservation group or groups corresponding to the LOCKSS network your system is joining.\n- The path for the primary content data storage area, any additional content data storage areas, log data storage area and temporary data storage area.\n- Username and password for the Web user interfaces.\n- A password for the PostgreSQL database.\n - Alternatively, if using an existing PostgreSQL database, the host name, port, schema, username and password for the external PostgreSQL database, as well as a prefix for database names.\n- A username and password for the Solr database.\n - Alternatively, if using an existing Solr database, the host name, port, username and password for the external Solr database, as well as the core name for the LOCKSS repository.\n- Whether you wish to use the LOCKSS Metadata Extraction Service, LOCKSS metadata Service, LOCKSS SOAP Compatibility Service, OpenWayback Web replay engine, and Pywb Web replay engine.\n\nSome notes about using `configure-lockss`:\n\n- When run the first time, some of the questions asked by the script will have a suggested or default value, displayed in square brackets; hit `Enter` to accept the suggested value, or type the correct value and hit `Enter`.\n- Any subsequent runs will use the previous values as the default value; review and hit `Enter` to leave unchanged.\n- Password prompts will not display the previous value but can still be left unchanged with `Enter`.\n4.2 Invoking configure-lockss\n\nTo invoke configure-lockss, simply run this command in the lockss user's lockss-installer directory as lockss:\n\n```\nscripts/configure-lockss\n```\n\nThe script will begin with the first series of configuration questions, about Network Settings.\n\n4.3 Network Settings\n\n4.3.1 Hostname\n\nPrompt: *Fully qualified hostname (FQDN) of this machine*\n\nEnter the machine's fully-qualified hostname (meaning with its domain name), for example locksstest.myuniversity.edu.\n\n4.3.2 IP Address\n\nPrompt: *IP address of this machine*\n\nIf the machine is publicly routable, meaning it has an IP address that can be used to identify it over the Internet, enter the publicly routable IP address. Otherwise, if the machine is accessible via network address translation (NAT), meaning it has an IP address that is valid only on your local network but it can be reached from the Internet via a NAT router, enter the internal IP address.\n\n4.3.3 Network Address Translation\n\n1. Prompt: *Is this machine behind NAT?*\n\n If the machine is publicly routable, enter \\texttt{N}; otherwise, if the machine is not publicly routable but will be accessible via network address translation (NAT), enter \\texttt{Y}.\n\n2. If you answered \\texttt{Y}, you will be asked an additional configuration question:\n\n *External IP address for NAT*\n\n Enter the publicly routable IP address of the NAT router.\n\n4.3.4 Initial UI Subnet\n\nPrompt: *Initial subnet(s) for admin UI access*\n\nEnter a semicolon-separated list of subnets in CIDR or mask notation that should initially have access to the Web user interfaces (UI) of the system. The access list can be modified later via the UI.\n\n\\footnote{1\\ See \\textit{Running Commands as the lockss User}.}\n4.3.5 Container Subnet\n\n1. If `configure-lockss` detects a discrepancy between a previously used subnet for inter-container communication in the system and the subnet it would choose now, you may either see the warning:\n\n Container subnet has changed from `<former_subnet>` to `<new_subnet>`\n\n or be asked the question:\n\n Container subnet was `<former_subnet>`, we think it should now be `<new_subnet>`. Do you want to change it?\n\n in which case you should enter `Y` (recommended) or `N`.\n\n2. Prompt: *LOCKSS subnet for inter-service access control*\n\n Enter the subnet used for inter-container communication. We recommend accepting the proposed value by hitting Enter.\n\n4.3.6 LCAP Port\n\nPrompt: *LCAP V3 protocol port*\n\nEnter the port on the publicly routable IP address that will be used to receive LCAP (LOCKSS polling and repair) traffic. Historically, most LOCKSS nodes use 9729.\n\n4.4 Mail Settings\n\n4.4.1 Mail Relay\n\nPrompt: *Mail relay for this machine*\n\nEnter the hostname of this machine's outgoing mail server, for example `smtp.myuniversity.edu`.\n\n4.4.2 Mail Relay Credentials\n\n1. Prompt: *Does the mail relay `<mailhost>` need a username and password?*\n\n If the outgoing mail server does not require password authentication, enter `N`; otherwise, enter `Y`.\n\n2. If you answered `Y`, you will be asked additional configuration questions:\n\n 1. Prompt: *User for `<mailhost>`*\n\n Enter a username for the mail server.\n\n 2. Prompt: *Password for `<mailuser>@<mailhost>`*\n\n Enter the password for the username on the mail server.\n\n 3. Prompt: *Password for `<mailuser>@<mailhost>` (again)*\n\n Re-enter the password for the username on the mail server. If the two passwords do not match, the password will be asked again.\n4.4.3 Administrator Email\n\nPrompt: *E-mail address for administrator*\n\nEnter the e-mail address of the person or team who will administer the LOCKSS system on this machine.\n\n4.5 Preservation Network Settings\n\n4.5.1 Configuration URL\n\n1. Prompt: *Configuration URL*\n \n Accept the default [(http://props.lockss.org:8001/demo/lockss.xml)](http://props.lockss.org:8001/demo/lockss.xml) if you are not running your own LOCKSS network; otherwise, enter the URL of the LOCKSS network configuration file provided by your LOCKSS network administrator.\n\n2. If the configuration URL begins with https:, you will be asked additional configuration questions:\n \n 1. Prompt: *Verify configuration server authenticity?* \n \n Enter Y if you would like to check the authenticity of the configuration server using a custom keystore; otherwise enter N.\n\n 2. If you answered Y, you will be asked an additional configuration question: \n \n *Server certificate keystore*\n \n Enter the path of a Java keystore used to verify the authenticity of the configuration server.\n\n4.5.2 Configuration Proxy\n\nPrompt: *Configuration proxy (host:port)*\n\nIf the configuration URL can be reached directly, leave this blank; otherwise, if a proxy server is required to reach the configuration URL, enter its host and port in host:port format (for example proxy.myuniversity.edu:8080).\n\n4.5.3 Preservation Groups\n\nPrompt: *Preservation group(s)*\n\nAccept the default (demo) if you are not running your own LOCKSS network; otherwise, enter a semicolon-separated list of LOCKSS network identifiers as provided by your LOCKSS network administrator, for example ournetwork or prod;usdocspln.\n\n4.6 Storage Areas\n\nThe LOCKSS system needs storage areas to store data:\n\n- One or more **content data storage areas** to store preserved content, as well as several databases.\n- A **log data storage area** to store log files.\n- A **temporary data storage area** to store temporary files.\nDepending on your host system's layout, these storage areas may all be the same, or all be different mount points or paths.\n\nSubdirectories will be created in each storage area to fit the needs of a system component; for example, `lockss-stack-cfg-data` is the LOCKSS configuration service's content data directory in the content data storage areas, and `lockss-stack-repo-logs` is the LOCKSS repository service's log data directory in the log data storage area.\n\n### 4.6.1 Content Data Storage Areas\n\n1. **Prompt: Root path for primary content data storage**\n Enter the full path of a directory to use as the root of the main storage area of the LOCKSS system, where preserved content will be stored along with several databases. It is the analog of `/cache0` in the classic LOCKSS system.\n\n2. **Prompt: Use additional directories for content data storage?**\n If you want to use more than one filesystem to store preserved content, enter `Y`; otherwise, enter `N`.\n\n3. If you answered `Y`, you will be asked an additional configuration question:\n \n *Root path for additional content data storage <count> (q to quit)*\n \n On each line, enter the full path of a directory to use as the root of an additional storage area, and enter `q` when done.\n\n### 4.6.2 Log Data Storage Area\n\n**Prompt: Root path for log data storage**\n\nThis directory is used as the root of the storage area for log files in the LOCKSS system. Accept the default (same directory as the content data storage directory root) by hitting `Enter`, or enter a custom path.\n\n### 4.6.3 Temporary Data Storage Area\n\n**Prompt: Root path for temporary data storage (local storage preferred)**\n\nThis directory is used as the root of the storage area for temporary files in the LOCKSS system. Accept the default (same directory as the content data storage directory root) by hitting `Enter`, or enter a custom path.\n\n**Tip:** The LOCKSS software makes heavy use of temporary storage, and we recommend that temporary directories be placed on a filesystem with relatively low latency. If the content data storage directories are on network storage (for example NFS), system performance may be improved by supplying a local directory for temporary data storage.\n\n**Caution:** Depending on the characteristics of the preservation activities undertaken by the system, in some circumstances content processing may require a substantial amount of temporary space, up to tens of gigabytes. Do not use a RAM-based `tmpfs` volume, or a directory in a space-constrained partition.\n4.7 Web User Interface Settings\n\n1. Prompt: *User name for web UI administration*\n Enter a username for the primary administrative user in the LOCKSS system's Web user interfaces.\n\n2. Prompt: *Password for web UI administration user <uiuser>*\n Enter a password for the primary administrative user.\n\n3. Prompt: *Password for web UI administration user <uiuser> (again)*\n Re-enter the password for the primary administrative user. If the two passwords do not match, the password will be asked again.\n\n4.8 Database Settings\n\n4.8.1 PostgreSQL\n\nPrompt: *Use embedded LOCKSS PostgreSQL DB Service?*\n\nSelect either option A or option B:\n\nA. Enter **Y** to use the **embedded PostgreSQL database**. This is recommended in most cases; a PostgreSQL database will be run and managed by the LOCKSS system internally. If you choose this option, see *Embedded PostgreSQL Database*.\n\nB. Enter **N** to use an **external PostgreSQL database**. Select this option if you wish to use an existing PostgreSQL database at your institution or one that you run and manage yourself. If you choose this option, see *External PostgreSQL Database*.\n\n**Embedded PostgreSQL Database**\n\nIf you select this option, you will be asked additional configuration questions:\n\n1. Prompt: *Password for PostgreSQL database*\n Enter the password for the embedded PostgreSQL database.\n\n **Warning:** This prompt is used to record the PostgreSQL database password in the LOCKSS system's configuration. If you change the value of the PostgreSQL database password here without actually changing the PostgreSQL database password, the LOCKSS system components will no longer be able to connect to the PostgreSQL database. See *Working with PostgreSQL* for details.\n\n2. Prompt: *Password for PostgreSQL database (again)*\n Re-enter the password for the embedded PostgreSQL database. If the two passwords do not match, the password will be asked again.\n\n3. Complete the *Solr* section next.\nExternal PostgreSQL Database\n\nIf you select this option, you will be asked additional configuration questions:\n\n1. Prompt: Fully qualified hostname (FQDN) of PostgreSQL host\n Enter the hostname of the external PostgreSQL database, for example postgres.myuniversity.edu.\n\n2. Prompt: Port used by PostgreSQL host\n Enter the port where the external PostgreSQL database can be reached, for example 5432.\n\n3. Prompt: Schema for PostgreSQL service\n Enter the schema name to be used by the LOCKSS system. The schema name used in the embedded PostgreSQL database is LOCKSS, but your database administrator may assign a different schema name to you.\n\n4. Prompt: Database name prefix for PostgreSQL service\n Enter the prefix to use for any LOCKSS-related database names in the schema. The database name prefix in the embedded PostgreSQL database is Lockss (note the uppercase/lowercase), but your database administrator may assign a different database name prefix.\n\n5. Prompt: Login name for PostgreSQL service\n Enter the username for the external PostgreSQL database. The username in the embedded PostgreSQL database is LOCKSS, but your database administrator may assign a different username to you.\n\n6. Prompt: Password for PostgreSQL database\n Enter the password for the username in the external PostgreSQL database.\n\n **Warning:** This prompt is used to record the PostgreSQL database password in the LOCKSS system's configuration. If you change the value of the PostgreSQL database password here without actually changing the PostgreSQL database password, the LOCKSS system components will no longer be able to connect to the PostgreSQL database. Contact your PostgreSQL database administrator for details.\n\n7. Prompt: Password for PostgreSQL database (again)\n Re-enter the password for the username in the external PostgreSQL database. If the two passwords do not match, the password will be asked again.\n\n8. Complete the Solr section next.\n\n4.8.2 Solr\n\nPrompt: Use embedded LOCKSS Solr Service?\n\nSelect **either** option A or option B:\n\nA. Enter Y to use the **embedded Solr database**. This is recommended in most cases; a Solr database will be run and managed by the LOCKSS system internally. If you choose this option, see Embedded Solr Database.\n\nB. Enter N to use an **external Solr database**. Select this option if you wish to use an existing Solr database at your institution or one that you run and manage yourself. If you choose this option, see External Solr Database.\nEmbedded Solr Database\n\nIf you select this option, you will be asked additional configuration questions:\n\n1. Prompt: *User name for LOCKSS Solr access*\n Enter the username for the embedded Solr database.\n\n2. Prompt: *Password for LOCKSS Solr access*\n Enter the password for the username in the embedded Solr database.\n\n3. Prompt: *Password for LOCKSS Solr access (again)*\n Re-enter the password for the username in the embedded Solr database. If the two passwords do not match, the password will be asked again.\n\n4. Complete the *Metadata Query Service* section next.\n\nExternal Solr Database\n\nIf you select this option, you will be asked additional configuration questions:\n\n1. Prompt: *Fully qualified hostname (FQDN) of Solr host*\n Enter the hostname of the external Solr database server, for example `solr.myuniversity.edu`.\n\n2. Prompt: *Port used by Solr host:*\n Enter the port used by the database server on the Solr host, for example 8983.\n\n3. Prompt: *Solr core repo name:*\n Enter name of the Solr core for the LOCKSS repository. The Solr core name used in the embedded Solr database is `lockss-repo`, but your database administrator may assign a different Solr core name.\n\n4. Prompt: *User name for LOCKSS Solr access*\n Enter the username for the external Solr database.\n\n5. Prompt: *Password for LOCKSS Solr access*\n Enter the password for the username in the external Solr database.\n\n6. Prompt: *Password for LOCKSS Solr access (again)*\n Re-enter the password for the username in the external Solr database. If the two passwords do not match, the password will be asked again.\n\n7. Complete the *Metadata Query Service* section next.\n\n4.9 LOCKSS Services\n\n4.9.1 Metadata Query Service\n\nPrompt: *Use LOCKSS Metadata Query Service?*\n\nEnter Y if you want the metadata query service to be run, otherwise N.\n4.9.2 Metadata Extraction Service\n\nPrompt: *Use LOCKSS Metadata Extraction Service?*\nEnter Y if you want the metadata extraction service to be run, otherwise N.\n\n4.9.3 SOAP Compatibility Service\n\nPrompt: *Use LOCKSS SOAP Compatibility Service?*\nEnter Y if you want the SOAP compatibility service to be run, otherwise N.\n\n4.10 Web Replay Settings\n\n4.10.1 Pywb\n\nPrompt: *Use LOCKSS Pywb Service?*\nEnter Y to run an embedded Pywb engine for Web replay; otherwise, enter N.\n\n4.10.2 OpenWayback\n\n1. Prompt: *Use LOCKSS OpenWayback Service?*\nEnter Y to use an embedded OpenWayback engine for Web replay; otherwise, enter N.\n\n2. If you answered Y, you will be asked an additional configuration question:\n\n *Okay to turn off authentication for read-only requests for LOCKSS Repository Service?*\n\n OpenWayback currently does not supply user credentials when reading content from the LOCKSS repository, so the repository must be configured to respond to unauthenticated read requests. Enter Y to accept this, otherwise you will see the warning:\n\n *Not enabling OpenWayback Service*\n\n and OpenWayback will not be run.\n\n4.11 Final Steps\n\n1. Prompt: *OK to store this configuration?*\nEnter Y if the configuration values are to your liking; otherwise, enter N to make edits.\n\n2. If you answer Y, `configure-lockss` will perform the final configuration steps. You may be asked to confirm before directories are created for the first time:\n\n `<directory> does not exist; shall I create it?`\n\n or before directory permissions are changed:\n\n `<directory> is not writable; shall I chown it?`\n\n In each case, enter Y for \"yes\" and N for \"no\".\nRUNNING THE LOCKSS SYSTEM\n\nThe commands in this section are all run as the lockss user\\(^1\\) in the lockss user's lockss-installer directory.\n\n### 5.1 Starting the LOCKSS System\n\nRun `scripts/start-lockss`. This script will call in turn:\n\n- `scripts/generate-lockss`: This script takes your configuration data and turns it into a set of configuration files containing the right values.\n- `scripts/assemble-lockss`: This script puts the configuration files and puts them in the right places, and ensures that all storage volumes are ready for use (creating them if necessary).\n- `scripts/deploy-lockss`: This script deploys your LOCKSS stack by invoking Kubernetes.\n\nThe `start-lockss` accepts some options:\n\n--\\texttt{update} (-u)\n\nForce the system to check for newer container images of the system's components (LOCKSS services, embedded databases, embedded Web replay engines...) before deploying the system to Kubernetes.\n\n--\\texttt{wait} (-w)\n\nAfter deploying the system to Kubernetes and waiting for the system's containers to come up, additionally wait for an internal signal from the system that the system's components are fully initialized. (Currently this internal signal comes from the poller service.)\n\n### 5.2 Shutting down the LOCKSS System\n\nRun `scripts/stop-lockss`.\n\n\\(^1\\) See *Running Commands as the lockss User*\n5.3 Restarting a Running LOCKSS System\n\nRun scripts/restart-lockss.\n\nThe restart-lockss accepts the same options as start-lockss.\n\n5.4 Removing a Configured LOCKSS System\n\nTo remove all configurations, volumes and networks configured by the LOCKSS system in Kubernetes, run scripts/uninstall-lockss. This will not remove files from the persistent store.\nThis chapter describes how to use the LOCKSS system.\n\nThese sections are under construction. The user interface of the LOCKSS 2.x is currently largely similar to that of the classic LOCKSS system (1.x); you can refer to the classic LOCKSS system manual in the meantime for similar information.\n\n6.1 Using the LOCKSS Configuration Service\n\nNote: This section is under construction.\n\n6.1.1 Accessing the Web User Interface\n\nIf you are already connected to the Web user interface (UI) of another component of the LOCKSS System, click Config Service in the top-left menu.\n\nAlternatively, if your primary hostname is <HOST>, you can use your browser to connect to the LOCKSS Configuration Service Web user interface (UI) at http://<HOST>:24621.\n\nEnter your Web UI username and password to login if prompted.\n\n6.1.2 Adding Archival Units\n\nTo add AUs to the system for preservation:\n\n1. In the top-right menu, click Journal Configuration.\n2. In the center menu, click Add AUs.\n3. Select one or more collections of AUs by selecting the checkbox next to the appropriate collection.\n4. Click the Select AUs button. It may take a bit of time (60+ seconds) for the next screen to appear, while the list of AUs is built.\n5. Select one or more AUs from the AU list. You may click Select All if you would like to select all AUs. If you choose to use select all AUs, please note that the next step may take some time to load.\n6. Click the Add Selected AUs button. The time it takes for the page to refresh depends on the number of AUs added. Give the LOCKSS system some time to load the AUs and reload the page before moving on.\n7. A screen will show a list of added AUs. Crawling of these new AUs will start automatically -- no further action is necessary unless prompted by a footnote next to an AU’s name.\n6.1.3 Configuring a Crawl Proxy\n\nIf Web crawls must be routed through a Web proxy:\n\n1. In the top-right menu, click Content Access Options.\n2. In the center menu, click Proxy Client Options.\n3. Select the Proxy crawls checkbox.\n4. Enter the hostname and port of the Web proxy in the HTTP Proxy host and Port text areas, respectively.\n5. Click the Update Proxy Client button.\n\n6.1.4 Managing Access to the Web User Interfaces\n\nThis section is under construction.\n\n6.2 Using the LOCKSS Crawler Service\n\nNote: This section is under construction.\n\n6.2.1 Accessing the Web User Interface\n\nNote: Currently the crawler service is run as part of the poller service.\n\nIf you are already connected to the Web user interface (UI) of another component of the LOCKSS System, click Crawler Service in the top-left menu.\n\nAlternatively, if your primary hostname is <HOST>, you can use your browser to connect to the LOCKSS Configuration Service Web user interface (UI) at http://<HOST>:24631.\n\nEnter your Web UI username and password to login if prompted.\n\n6.2.2 Monitoring Crawl Status in the System\n\nThe Crawl status of all configured AUs is available in the Archival Unit table\n\n1. In the top-right menu, click Daemon Status.\n2. Open the control in the middle of the screen that says Overview and select Archival Units:guilabel: from the drop down menu.\n • If prompted, enter your Username and Password again.\n • It will take a bit of time for the next screen to appear while the AU list is being built.\n3. The Archival Units screen lists statistics for each configured AU\n • the Last Successful Crawl column provides a timestamp of the most recent successful crawl.\n • the Last Crawl Start column provides a timestamp of the last attempted crawl.\n • the Last Crawl Result column provides the exit status of the last attempted crawl.\n6.2.3 Causing an Archival Unit to Crawl\n\nArchival units (AUs) that have been added to the system for preservation crawl periodically, but you can cause an AU to crawl on demand:\n\n1. In the top-right menu, click *Debug Panel*.\n2. Select an AU in the *AU Actions: select AU* drop-down list.\n3. Click the *Start Crawl* button.\n4. If the AU has crawled recently, you will be prompted to confirm that you wish to override the usual recrawl interval by clicking on the *Force Start Crawl* button.\n\n6.2.4 Crawl Status Screen\n\nTo inspect the state of crawls, access the *Crawl Status* screen:\n\n1. In the top-right menu, click *Daemon Status*.\n2. In the center drop-down list, select *Crawl Status*. Alternatively, in the center overview, click on the second line, which says \"N active crawls\".\n\nTop-Level Crawl Information\n\nThe top left of the Crawl Status table contains the number of active, successful or failed crawls, and a countdown until the next time the system will look at the AUs being preserved and pick some that are ready to crawl or recrawl.\n\nCrawl Status Entry\n\nEach line in the Crawl Status table contains:\n\n- The name of the AU\n- The type of crawl\n- The start time of the crawl\n- The duration of a finished or in-progress crawl\n- The status of the crawl\n- The number of bytes fetched over the network as part of the crawl\n- The number of URLs fetched as part of the crawl\n- The number of URLs parsed for more links\n- The number of URLs remaining to be fetched as part of this crawl\n- The number of URLs encountered as part of this crawl but excluded from being fetched\n- The number of URLs fetched as part of the crawl, that received an HTTP Not Modified response\n- The number of URLs that caused errors as part of this crawl\n- The number of different content types encountered as part of the crawl\n\nMost of these values can be clicked to see a list of the corresponding objects.\n6.3 Using the LOCKSS Poller Service\n\nNote: This section is under construction.\n\n6.3.1 Accessing the Web User Interface\n\nIf you are already connected to the Web user interface (UI) of another component of the LOCKSS System, click Poller Service in the top-left menu.\n\nAlternatively, if your primary hostname is <HOST>, you can use your browser to connect to the LOCKSS Configuration Service Web user interface (UI) at http://<HOST>:24631.\n\nEnter your Web UI username and password to login if prompted.\n\n6.3.2 Requesting Polls\n\nThis section is under construction.\n\n6.3.3 Monitoring Polling and Voting\n\nThis section is under construction.\n\n6.4 Using the LOCKSS Metadata Extraction Service\n\nNote: This section is under construction.\n\n6.4.1 Accessing the Web User Interface\n\nIf you are already connected to the Web user interface (UI) of another component of the LOCKSS System, click Metadata Extraction Service in the top-left menu.\n\nAlternatively, if your primary hostname is <HOST>, you can use your browser to connect to the LOCKSS Configuration Service Web user interface (UI) at http://<HOST>:24641.\n\nEnter your Web UI username and password to login if prompted.\n\n6.4.2 Requesting Metadata Extraction\n\nThis section is under construction.\n6.5 Using the LOCKSS Metadata Service\n\nNote: This section is under construction.\n\n6.5.1 Accessing the Web User Interface\n\nIf you are already connected to the Web user interface (UI) of another component of the LOCKSS System, click Metadata Service in the top-left menu.\n\nAlternatively, if your primary hostname is <HOST>, you can use your browser to connect to the LOCKSS Configuration Service Web user interface (UI) at http://<HOST>:24651.\n\nEnter your Web UI username and password to login if prompted.\n\n6.5.2 Requesting Metadata Information\n\nThis section is under construction.\n\n6.6 Replaying Web Content with Pywb\n\n6.6.1 Accessing the Pywb User Interface\n\nGiven that your primary hostname is samp:/<HOST>/, you can use your browser to connect to the Pywb user interface (UI) at http://<HOST>:8080.\n\n6.6.2 Replaying a URL\n\nTo view a URL from Pywb:\n\n1. The Pywb screen provides a list of links to available collections. Click on the top-most collection which should be /lockss.\n2. Enter the URL you want to replay in the URL search box.\n3. Click the Search button.\n4. Replay the most recent URL by clicking on the topmost entry of the third column.\n\n6.6.3 Finding a URL From an AU to Replay\n\nThere are multiple ways to discover URLs belonging to an AU in the Configuration Service UI:\n\n1. Obtaining a URL by clicking on \"pages fetched\" inside of crawl status\n • In the top-right menu, click Daemon Status.\n • Open the control in the middle of the screen that says Overview and select Crawl Status from the drop down menu.\n • Picking an AU from the active crawls, click on the number associated with Pages Fetched to bring up a list of URLs that have been crawled.\n• Copy one of the URLs and paste it in the Pywb interface as described previously.\n\n2. Obtaining a Substance URL\n• In the top-right menu, click Daemon Status.\n• Open the control in the middle of the screen that says Overview and select Archival Units from the drop down menu. If prompted, enter your Username and Password again. It will take a bit of time for the next screen to appear while the AU list is being built.\n• Select an AU by clicking on the AU title in the first column.\n• Open the Substance URLs link\n• Copy one of the URLs and paste it in the Pywb interface as described previously.\n\n6.7 Replaying Web Content with OpenWayback\n\n6.7.1 Accessing the OpenWayback User Interface\nGiven that your primary hostname is samp:/{<HOST>}, you can use your browser to connect to the Pywb user interface (UI) at http://<HOST>:8080/wayback.\n\n6.7.2 Replaying a URL\nTo view a URL from OpenWayback:\n1. Enter the URL you want to replay in the URL search box.\n2. Click the Search button.\n3. Select the Year* or leave as :guilabel: ’All\n4. Click Take Me Back.\n\n6.7.3 Finding a URL From an AU to Replay\nThere are multiple ways to discover URLs belonging to an AU in the Configuration Service UI:\n1. Obtaining a URL by clicking on \"pages fetched\" inside of crawl status\n • In the top-right menu, click Daemon Status.\n • Open the control in the middle of the screen that says Overview and select Crawl Status from the drop down menu.\n • Picking an AU from the active crawls, click on the number associated with Pages Fetched to bring up a list of URLs that have been crawled.\n • Copy one of the URLs and paste it in the OpenWayback interface as described previously.\n2. Obtaining a Substance URL\n • In the top-right menu, click Daemon Status.\n • Open the control in the middle of the screen that says Overview and select Archival Units from the drop down menu. If prompted, enter your Username and Password again. It will take a bit of time for the next screen to appear while the AU list is being built.\n • Select an AU by clicking on the AU title in the first column.\n• Open the Substance URLs link\n• Copy one of the URLs and paste it in the OpenWayback interface as described previously.\n\n6.8 Using the Kubernetes Dashboard\n\nKubernetes comes with the Kubernetes Dashboard, a web-based user interface (UI).\n\nTo facilitate installing and interacting with the Kubernetes Dashboard, the LOCKSS Installer offers the dashboard-util script.\n\n6.8.1 Installing the Kubernetes Dashboard\n\nTo install the Kubernetes Dashboard, run this command:\n\n```\nscripts/dashboard-util --install\n```\n\nIf the installation succeeds, the program will also display the login URL and the bearer token.\n\n6.8.2 Accessing the Kubernetes Dashboard\n\nTo access the Kubernetes Dashboard:\n\n1. Create a secure channel to your K3s cluster with the following command:\n\n```\nk3s kubectl proxy &\n```\n\n **Note:** This command runs in the background “forever”.\n\n2. Obtain the login URL with the following command:\n\n```\nscripts/dashboard-util --url\n```\n\n3. Obtain the login token with the following command:\n\n```\nscripts/dashboard-util --token\n```\n\n4. Open a browser and go to the login URL.\n5. Make sure the Token radio button is selected.\n6. Copy and paste the login token into the Enter token text field.\n\n---\n\n1 This command is relative to the lockss user’s lockss-installer directory.\n6.8.3 Using the Kubernetes Dashboard UI\n\nWhen the dashboard comes up, it will be in the default namespace. Click on the namespace pull-down menu near the top and select the lockss namespace to see the LOCKSS components. If all of your deployments are running and ready, the three circles at the top should be green. In the left hand panel you can select the components you are interested in:\n\n- Click on Services to see the cluster IP for each of the running services. You can click on a specific service to see more detailed information.\n- Click on Deployments to see a list of services and their CPU and memory usage. You can access specific services and deployments from here.\n- Click on Pods. This will give you information about all the pods running. Click on a pod of interest to obtain more granular information:\n \n **View logs**\n Since LOCKSS output logs are persisted to a local directory, there will be very little in the Kubernetes logs if the container came up without errors.\n \n **Exec into pods**\n This will open a terminal window into the container.\n \n **Edit the pod resource**\n This will allow you to view and edit the YAML file which was used to start the pod. The edit will not persist on restart.\n \n **Delete the pod**\n While this will delete the current pod, a new pod will be spawned by the deployment with a new pod ID.\n\n6.8.4 Updating the Kubernetes Dashboard\n\nTo update the Kubernetes Dashboard to the most recent release, run this command:\n\n```\nscripts/dashboard-util --update\n```\n\n6.8.5 Removing the Kubernetes Dashboard\n\nTo remove the Kubernetes Dashboard from the kubernetes-dashboard namespace, run this command:\n\n```\nscripts/dashboard-util --remove\n```\n\nSee Also\n\n- Web UI (Dashboard) on the Kubernetes website.\nThis chapter contains sections of additional information about troubleshooting the LOCKSS system. Sections include guidance for troubleshooting networking-related components like `iptables`, `firewalld`, and `ufw`, and K3s-related components like CoreDNS, the K3s Installer, the K3s Configuration Checker.\n\n### 7.1 Known Issues\n\n*This section was last updated: 2023-01-23.*\n\n#### Expired K3s Certificate\n\nLOCKSS-provided scripts like `scripts/stop-lockss` or `scripts/restart-lockss` that interact with the K3s server may display error messages that include:\n\n```\nerror: You must be logged in to the server (Unauthorized)\n```\n\nIn parallel, the host system log might contain messages similar to:\n\n```\nclient_builder_dynamic.go:197: get or create service account failed: Get \"https://127.0.\n˓→0.1:6444/api/v1/namespaces/kube-system/serviceaccounts/generic-garbage-collector\":␣\n˓→x509: certificate has expired or is not yet valid: current time 2023-01-22T03:32:05-\n˓→08:00 is after 2023-01-21T02:13:28Z\n```\n\nThis is caused by a bug in the version of K3s that currently ships with the LOCKSS system, whereby the auto-rotation of a certificate after the K3s server runs continuously for one year does not take place correctly. Future releases of the LOCKSS system will use a newer version of K3s without this bug. In the meantime, to work around this problem, simply restart the K3s service with `systemctl` as `root`:\n\n```\nsystemctl restart k3s\n```\n\nScripts that interact with the K3s server should then again work as expected.\nSecurity\n\n- In the \"alpha\" phase of development of LOCKSS 2.0, there are no access controls on Kubernetes API. It is not accessible from outside the machine, but any local user can access the API, so they can stop the LOCKSS containers, change their contents, read secrets, etc. We plan to enable access controls in the \"beta\" phase.\n- In the Classic LOCKSS system (1.x), the LCAP SSL key could only be read by root, but now it can also be read by lockss.\n\nDNS Resolution\n\nK3s' default DNS cache timeout is 30 seconds, which results in enough repetitive upstream queries to trigger alarms at some institutions. One remediation is to change the CoreDNS configuration by editing its configmap.\n\nWith K3s, changes made to CoreDNS's configmap with `kubectl apply` do not persist, because the configmap is constantly reloaded from `/var/lib/rancher/k3s/server/manifests/coredns.yaml`. Additionally, K3s overwrites the file with the defaults at startup, so changes there are not really persistent either.\n\nThe LOCKSS Installer offers the script `scripts/coredns-cron-hack`, which sets the CoreDNS cache timeout to 30 minutes. It should be run once, as root, after each time K3s starts. Absent a good way to do that, it is harmless to run it periodically from root's crontab. The recommended use is to copy it to a root-owned file in `/etc/cron.hourly`.\n\nHarmless PID File Errors\n\nThe stdout log files of the various LOCKSS service containers contain the following error messages at startup:\n\n```\n/usr/local/bin/docker-entrypoint: line 374: can't create /var/run/docker-entrypoint.pid: Permission denied\n```\n\nThis is harmless and will be addressed in the a future release of the system.\n\n7.2 Troubleshooting iptables\n\nThis section provides troubleshooting information for the Configuring iptables for K3s phase of /installing/installer.\n\n7.2.1 Switch iptables to legacy mode via Alternatives\n\nK3s 1.21.5+k3s1 (the version used by LOCKSS 2.0-alpha7) does not always work with `iptables` versions 1.8.0-1.8.3 when run via Alternatives but not in legacy mode, for instance in some Debian or Ubuntu systems\\(^1\\). If `install-lockss` detects this situation, you will see a warning message and the following prompt\\(^2\\):\n\nSwitch iptables to legacy mode via Alternatives?\n\n\\(^1\\) References:\n- `https://rancher.com/docs/k3s/latest/en/known-issues/`\n- `https://github.com/kubernetes/kubernetes/issues/71305`\n- `https://github.com/k3s-io/k3s/issues/116`\n - `https://github.com/k3s-io/k3s/issues/116#issuecomment-624770403`\n- `https://github.com/k3s-io/k3s/issues/703`\n\n\\(^2\\) See Configuring iptables for K3s.\nEnter Y to accept the proposed `iptables` configuration. **If you bypass the proposed configuration, K3s may malfunction.**\n\nThe remediation attempted by `install-lockss` is equivalent to:\n\n```\n# Required only if ufw is active\nufw disable\n\n# Required\nupdate-alternatives --set iptables /usr/sbin/iptables-legacy\n\n# Required\nupdate-alternatives --set ip6tables /usr/sbin/ip6tables-legacy\n\n# Optional\nupdate-alternatives --set arptables /usr/sbin/arptables-legacy\n\n# Optional\nupdate-alternatives --set ebtables /usr/sbin/ebtables-legacy\n\n# Required only if ufw was active\nufw enable\n```\n\n### 7.2.2 Post-Installation Changes to `iptables`\n\nIf your system did not initially need an adjustment for `iptables` at the time K3s was installed, but later does (for example because `iptables` is upgraded from a pre-1.8.0 version to version 1.8.0 or later), run this command (relative to the **LOCKSS Installer Directory**) as a privileged user who can become `root` via `sudo`:\n\n```\nscripts/install-lockss --configure-iptables\n```\n\nThis will run only the **Configuring iptables for K3s** phase of `install-lockss`.\n\n### 7.3 Troubleshooting `firewalld`\n\nThis section provides troubleshooting information for the **Configuring firewalld for K3s** phase of `/installing/installer`.\n\n#### 7.3.1 Add 10.42.0.0/16 and 10.43.0.0/16 to `firewalld`'s trusted zone\n\nIf your system is running the `firewalld` firewall, it is necessary to add K3s' pod and service subnets\\(^1\\) to `firewalld`'s trusted zone for K3s to work properly\\(^2\\). If `install-lockss` detects this situation, you will see a warning message\n\n---\n\n3 See [Running Commands as a Privileged User](#).\n\n1 By default, K3s' pod subnet is 10.42.0.0/16 and service subnet is 10.43.0.0/16.\n\n2 For operating systems in the RHEL family (CentOS, Rocky Linux, AlmaLinux OS...), the action recommended by the K3s manual is to disable `firewalld` entirely (see [https://rancher.com/docs/k3s/latest/en/advanced/#additional-preparation-for-red-hat-centos-enterprise-linux](https://rancher.com/docs/k3s/latest/en/advanced/#additional-preparation-for-red-hat-centos-enterprise-linux)), but `install-lockss` takes a lighter approach commonly used in the K3s community.\n\nReferences:\n- [https://github.com/k3s-io/k3s/issues/1556](https://github.com/k3s-io/k3s/issues/1556)\n- [https://github.com/k3s-io/k3s/issues/1556#issuecomment-604112415](https://github.com/k3s-io/k3s/issues/1556#issuecomment-604112415)\nand the following prompt:\n\n*Add 10.42.0.0/16 and 10.43.0.0/16 to firewalld’s trusted zone?*\n\nEnter Y to accept the proposed `firewalld` configuration. **If you bypass the proposed configuration, K3s may malfunction.**\n\nThe `firewalld` configuration attempted by `install-lockss` is equivalent to:\n\n```\nfirewall-cmd --permanent --zone=trusted --add-source=10.42.0.0/16\nfirewall-cmd --permanent --zone=trusted --add-source=10.43.0.0/16\nfirewall-cmd --reload\n```\n\n### 7.3.2 Post-Installation Changes to `firewalld`\n\nIf your system did not initially use `firewalld` at the time K3s was installed, but later does (for example because `firewalld` becomes enabled), run this command (relative to the `LOCKSS Installer Directory`) as a privileged user who can become `root` via `sudo`:\n\n```\nscripts/install-lockss --configure-firewalld\n```\n\nThis will run only the *Configuring firewalld for K3s* phase of `install-lockss`.\n\n### 7.4 Troubleshooting `ufw`\n\nThis section provides troubleshooting information for the *Configuring ufw for K3s* phase of `installing/installer`.\n\n#### 7.4.1 Allow traffic from 10.42.0.0/16 and 10.43.0.0/16 via `ufw`\n\nIf your system is running the `ufw` firewall, it is necessary to allow traffic from K3s' pod and service subnets via `ufw` for K3s to work properly. If `install-lockss` detects this situation, you will see a warning message and the following prompt:\n\n*Allow traffic from 10.42.0.0/16 and 10.43.0.0/16 via ufw?*\n\nEnter Y to accept the proposed `ufw` configuration. **If you bypass the proposed configuration, K3s may malfunction.**\n\nThe `firewalld` configuration attempted by `install-lockss` is equivalent to:\n\n```\n3 See Configuring firewalld for K3s.\n4 See Running Commands as a Privileged User.\n1 By default, K3s’ pod subnet is 10.42.0.0/16 and service subnet is 10.43.0.0/16.\n2 References:\n • https://github.com/k3s-io/k3s/issues/1280\n – https://github.com/k3s-io/k3s/issues/1280#issuecomment-663269728\n3 See Configuring ufw for K3s.\n7.4.2 Post-Installation Changes to ufw\n\nIf your system did not initially use ufw at the time K3s was installed, but later does (for example because ufw becomes enabled), run this command (which is relative to the LOCKSS Installer Directory) as a privileged user who can become root via sudo:\n\n```\nscripts/install-lockss --configure-ufw\n```\n\nThis will run only the Configuring ufw for K3s phase of install-lockss.\n\n7.5 Troubleshooting CoreDNS\n\nThis section provides troubleshooting information for the Configuring CoreDNS for K3s phase of /installing/installer.\n\n7.5.1 CoreDNS does not allow a loopback address to be given to Kubernetes pods as an upstream DNS server\n\nIf both /etc/resolv.conf and /run/systemd/resolve/resolv.conf (files used to list the IP address of DNS servers) contain loopback addresses, CoreDNS (a component of the K3s Kubernetes cluster that handles DNS resolution) will not work properly. If install-lockss detects this situation, you will see a warning message including CoreDNS does not allow a loopback address to be given to Kubernetes pods as an upstream DNS server, and the following prompt:\n\n```\nIP address(es) of DNS resolvers, separated by ';'\n```\n\nEnter a semicolon-separated list of DNS server IP addresses that are not loopback addresses or hit Enter to accept the proposed value.\n\n7.5.2 Post-Installation Changes to DNS\n\nIf the DNS settings of your system change after K3s is initially installed (for example if DNS servers are added or removed), run this command (which is relative to the LOCKSS Installer Directory) as a privileged user who can become root via sudo:\n\n```\nscripts/install-lockss --configure-coredns\n```\n\nReferences:\n\n\n2. See Configuring CoreDNS for K3s.\n\n3. See Running Commands as a Privileged User.\nThis will run only the Configuring CoreDNS for K3s phase of install-lockss.\n\n7.6 Troubleshooting the K3s Installer\n\nThe LOCKSS Installer’s install-lockss script installs K3s by executing Rancher’s official K3s Installer from https://get.k3s.io/, after checking that various system, firewall and DNS prerequisites are addressed (see /installing/installer). However, the installation can still run into issues and fail. Some of the error messages you might encounter are documented below, but you may need to refer to the official K3s documentation or use a search engine to look up a specific error message.\n\n7.6.1 Enabling User Namespaces in RHEL 7 and CentOS 7\n\nK3s requires user namespaces, a feature generally available and enabled in many Linux flavors. However, some RHEL 7 and CentOS 7 systems do not have user namespace enabled by default. This can cause the Checking K3s Prerequisites or Testing the K3s Node phases of install-lockss or the optional Checking the K3s Configuration phase to fail.\n\nTo resolve this issue in RHEL 7 or CentOS 7:\n\n1. Edit the file /etc/default/grub as root:\n\n 1. Look for the line beginning with GRUB_CMDLINE_LINUX=, for example:\n\n ```\n GRUB_CMDLINE_LINUX=\"no_timer_check console=tty0 console=ttyS0,115200n8 net.\n →ifnames=0 biosdevname=0 elevator=noop crashkernel=auto\"\n ```\n\n This line defines a space-separated list of boot arguments.\n\n 2. Add user_namespace.enable=1 to the beginning of the space-separated list, for instance:\n\n ```\n GRUB_CMDLINE_LINUX=\"user_namespace.enable=1 no_timer_check console=tty0,␣\n →console=ttyS0,115200n8 net.ifnames=0 biosdevname=0 elevator=noop␣\n →crashkernel=auto\"\n ```\n\n2. Run the following command as root:\n\n ```\n grub2-mkconfig -o /boot/grub2/grub.cfg\n ```\n\n **Note:** If EFI is in use, the file to use for the -o option will not be /boot/grub2/grub.cfg exactly. For example on CentOS, it may be /boot/efi/EFI/centos/grub.cfg.\n\n3. Reboot the system.\n\n4. Check that the change took effect. To do so, look at the contents of /proc/cmdline (for example type cat /proc/cmdline) and verify that it now contains user_namespace.enable=1.\n\n **Note:** If the change did not take effect, it could be an indication that a different grub.cfg file is needed for the -o option of grub2-mkconfig command above.\n\n---\n\n1 References:\n\n - https://fortuitousengineer.com/installing-kubernetes-k3s-on-centos-rhel-hosts/\n\n2 See Running Commands as root.\n7.6.2 Installing apparmor-parser\n\nK3s uses Apparmor in systems where it is enabled. However, some systems, especially OpenSUSE systems, have Apparmor enabled but apparmor-parser is not installed by default. This can cause the Checking K3s Prerequisites or Installing K3s phases of install-lockss or the optional Checking the K3s Configuration phase to fail.\n\nTo resolve this issue in OpenSUSE, run these zypper commands as root:\n\n```\nzypper refresh\nzypper --non-interactive install apparmor-parser\n```\n\nor equivalently:\n\n```\nzypper refresh\nzypper -n install apparmor-parser\n```\n\nTip: In other Linux flavors, use similar package installation commands.\n\n7.6.3 Failed to apply container_runtime_exec_t to /usr/local/bin/k3s\n\nIn some Fedora systems, the K3s installer may fail with an error message similar to the following:\n\n```\n[ERROR] Failed to apply container_runtime_exec_t to /usr/local/bin/k3s, please install:\n yum install -y container-selinux\n yum install -y https://rpm.rancher.io/k3s/stable/common/centos/8/noarch/k3s-selinux-\n → 0.3-0.el8.noarch.rpm\n```\n\nThe specific commands and version numbers may vary from the example above.\n\nTo resolve this problem, run the recommended commands as root.\n\n7.6.4 k3s-selinux requires container-selinux\n\nIn some Oracle Linux 7 systems, you may see an error message similar to the following:\n\n```\nError: Package: k3s-selinux-0.3-0.el7.noarch (rancher-k3s-common-stable)\n Requires: container-selinux >= 2.107-3\nYou could try using --skip-broken to work around the problem\nYou could try running: rpm -Va --nodesign --nodigest\n```\n\nThe specific commands and version numbers may vary from the example above.\n\nThis can occur in environments where the Oracle Linux 7 Addons Yum repository is not enabled by default, so Rancher's official K3s installer is unable to install the package container-selinux automatically.\n\nTo resolve this problem in Oracle Linux 7, run the following command as root:\n\n```\nyum-config-manager --enable ol7_addons\n```\n7.7 Troubleshooting the K3s Configuration Checker\n\nAfter installing K3s\\(^2\\), you may optionally run the K3s configuration checker `k3s check-config`\\(^3\\) (see Checking the K3s Configuration). This configuration checker runs through a more extensive series of tests, covering \"required\", \"generally necessary\", and \"optional\" system aspects needed by K3s.\n\nSome failures, especially in \"optional\" aspects, may not actually prevent the cluster from working normally, in the limited ways the LOCKSS system uses Kubernetes. Some of the error messages you might encounter are documented below, but you may need to refer to the official K3s documentation or use a search engine to look up a specific error message.\n\n7.7.1 iptables should be older than v1.8.0, newer than v1.8.3, or in legacy mode\n\nIn some instances, you may encounter an error message similar to the following:\n\n```\n/usr/sbin iptables v1.8.2 (nf_tables): should be older than v1.8.0, newer than v1.8.3, or in legacy mode (fail)\n```\n\nIn previous versions of K3s, this error message was also sometimes phrased as should be older than v1.8.0 or in legacy mode.\n\nThe `install-lockss` script should detect this situation and offer to switch `iptables` to legacy mode via Alternatives (see Troubleshooting iptables). If the error above occurs:\n\n- Verify that the Configuring iptables for K3s phase of `install-lockss` was not skipped.\n- Verify that, if applicable, the proposed `iptables` configuration changes in the Configuring iptables for K3s phase of `install-lockss` were not bypassed.\n- Using the Troubleshooting iptables section as reference, verify that the remediation attempted by `install-lockss` has taken effect.\n- Search the K3s issues database for issues related to `k3s check-config iptables` and your operating system.\n\n7.7.2 User namespaces disabled\n\nIn some RHEL 7 and CentOS 7 systems, you may receive the following error message:\n\n```\nRHEL7/CentOS7: User namespaces disabled; add 'user_namespace.enable=1' to boot command ...\n...line (fail)\n```\n\nTo resolve this issue, see Enabling User Namespaces in RHEL 7 and CentOS 7.\n\n\\(^2\\) See Installing K3s.\n\\(^3\\) See Checking the K3s Configuration.\n7.7.3 apparmor enabled but apparmor_parser missing\n\nIn some systems where Apparmor is enabled, you may receive the following error:\n\n```\napparmor: enabled, but apparmor_parser missing (fail)\n```\n\nTo resolve this issue, see *Installing apparmor_parser*.\n\n7.7.4 cgroup hierarchy nonexistent\n\nIn some Arch Linux, Debian and Fedora systems, you may see the following error message:\n\n```\ncgroup hierarchy: nonexistent?? (fail)\n```\n\nK3s supports cgroup2 but k3s `check-config` version 1.21.5+k3s1 (used in LOCKSS 2.0-alpha5) does not process this condition correctly. **This warning can be ignored.**\n\n7.7.5 links: aux/iptables should link to iptables-detect.sh\n\nIn some Fedora and OpenSUSE systems, you may encounter six related error messages like the following:\n\n```\nlinks: aux/ip6tables should link to iptables-detect.sh (fail)\nlinks: aux/ip6tables-restore should link to iptables-detect.sh (fail)\nlinks: aux/ip6tables-save should link to iptables-detect.sh (fail)\nlinks: aux/iptables should link to iptables-detect.sh (fail)\nlinks: aux/iptables-restore should link to iptables-detect.sh (fail)\nlinks: aux/iptables-save should link to iptables-detect.sh (fail)\n```\n\nThis is due to a bug in k3s `check-config`\\(^6\\), triggered in environments where there is no `iptables` system package installed. **This warning can be ignored.**\n\n7.7.6 swap should be disabled\n\n**This warning can be ignored:**\n\n```\nswap: should be disabled\n```\n\n7.7.7 CONFIG_INET_XFRM_MODE_TRANSPORT missing\n\n**This warning can be ignored:**\n\n```\nCONFIG_INET_XFRM_MODE_TRANSPORT: missing\n```\n\n\\(^6\\) Reference:\n- https://github.com/k3s-io/k3s/issues/4066\n - https://github.com/k3s-io/k3s/issues/4066#issuecomment-925137706\n\n7.7. Troubleshooting the K3s Configuration Checker\n7.8 Troubleshooting OverlayFS with XFS\n\nThis section provides troubleshooting information for the check_xfs phase of /installing/installer.\n\n7.8.1 Filesystem backing /var/lib/rancher is an XFS filesystem with ftype=0\n\nThe OverlayFS driver used by K3s will fail and prevent containers from starting, if the filesystem backing /var/lib/rancher is an XFS filesystem configured with the legacy ftype=0 setting that some older Linux systems defaulted to when creating XFS filesystems. To view or verify the setting of ftype from an XFS filesystem, use xfs_info (see step 1 below).\n\nThe recommended way fix to this issue is to reformat the XFS filesystem with ftype=1, or with another filesystem such as ext4. If this is not possible (e.g., because you are performing an in-place migration from LOCKSS 1.x to 2.x and the filesystem backing /var/lib/rancher is shared with other parts of the system), the workaround is to create a new XFS filesystem on another partition or a loopback device backed by a file on an existing filesystem.\n\nSetup of the latter is described below. Commands should be run as the root user.¹\n\n1. (Optional) Verify the existing XFS filesystem has ftype=0:\n\n ```\n xfs_info BLOCK DEVICE\n ...\n ...\n ...\n where BLOCK_DEVICE is the block device of the filesystem backing /var/lib/rancher.\n ```\n\n **Tip:** Use findmnt to determine the block device of the filesystem backing /var/lib/rancher:\n\n ```\n findmnt --target /var/lib/rancher\n ```\n\n The output should look similar to the following (some parameters may be different):\n\n<table>\n<thead>\n<tr>\n<th>TARGET</th>\n<th>SOURCE</th>\n<th>FSTYPE</th>\n<th>OPTIONS</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/</td>\n<td>/dev/mapper/root</td>\n<td>xfs</td>\n<td>rw,relatime,attr2,inode64,logbufs=8,logsize=32k,--noquota</td>\n</tr>\n</tbody>\n</table>\n\n In the example above, the block device is /dev/mapper/root (i.e., the SOURCE column).\n\n The output from xfs_info should look similar to the following (some parameters may be different):\n\n | meta-data=/dev/mapper/root isize=512 agcount=4, agsize=4194304 blks |\n | == sectsz=4096 attr=2, projid32bit=1 = crc=1 finobt=1, sparse=1, rmapbt=0 = reflink=1 bigtime=1 inobtcount=1 next64=0 data == bsize=4096 blocks=16777216, imaxpct=25 = sumit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0, ftype=0 log =internal log bsize=4096 blocks=16384, version=2 = sectsz=4096 sumit=1 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 |\n\n **Note:** In the example above, ftype=0. If your output contains ftype=1, there is nothing wrong with your XFS filesystem and you should not proceed with the instructions on this page!\n\n¹ See Running Commands as root.\n2. Stop the K3s service:\n\n```bash\nsystemctl stop k3s.service\n```\n\n3. Rename the existing /var/lib/rancher directory:\n\n```bash\nmv /var/lib/rancher /var/lib/rancher.backup\n```\n\n4. Allocate a file for the loopback device: This file will contain the XFS filesystem that will hold the K3s runtime environment and container images. We recommend allocating a minimum of 16GB. Allocate the file on a filesystem with sufficient space.\n\n **Note:** In this and the following examples, we allocate and use the file located at /var/lib/rancherfs.img.\n\n```bash\nfallocate -l 16g /var/lib/rancherfs.img\n```\n\n5. Create a new XFS filesystem with ftype explicitly set to 1:\n\n```bash\nmkfs.xfs -n ftype=1 /var/lib/rancherfs.img\n```\n\nYou may verify ftype=1 by running:\n\n```bash\nxfs_info /var/lib/rancherfs.img\n```\n\n6. Mount the loopback to /var/lib/rancher:\n\n```bash\nmount --mkdir -o loop /var/lib/rancherfs.img /var/lib/rancher\n```\n\n7. Edit /etc/fstab to make the loopback persistent across reboots: Use your favorite text editor to open /etc/fstab and append the following line to it:\n\n```bash\n/var/lib/rancherfs.img /var/lib/rancher xfs loop 0 0\n```\n\n8. Copy the existing K3s runtime environment to the new XFS filesystem:\n\n```bash\ncp -r /var/lib/rancher.backup/* /var/lib/rancher/.\n```\n\n9. Finally, restart the K3s service:\n\n```bash\nsystemctl start k3s.service\n```\n\n10. (Optional) If setup of the loopback was successful and K3s is running correctly, you may reclaim space by removing /var/lib/rancher.backup:\n\n```bash\nrm -rf /var/lib/rancher.backup\n```\nThis chapter covers some common system administration tasks related to running a LOCKSS system.\n\nSections include how to run commands as the root user, as a privileged user who can become root via sudo, or as the lockss user; how to update a Linux operating system; and how to install various system utilities like Curl, Wget or HTTPie.\n\n8.1 Running Commands as root\n\nSome commands or scripts in this manual are intended to be run as root. This section describes two methods for doing so.\n\n8.1.1 Running Commands as root With sudo\n\nIf you are logged in as a user who can run commands as root via sudo, simply add the following in front of the command listed in the manual:\n\n```\nsudo ...\n```\n\nFor example, if the command listed in the manual is `iptables -F`, you would type `sudo iptables -F`.\n\n8.1.2 Running Commands Directly as root\n\nIf you are logged in as root directly, you can simply run the command as listed in the manual, for example `iptables -F`.\n\n8.2 Running Commands as a Privileged User\n\nSome commands or scripts in this manual are intended to be run as a privileged user who can become root and lockss via sudo.\n\nCompared to running an entire command or script directly as root, this approach has the security advantage of being granular -- only those portions of the command or script that require root privileges will have root privileges, and only those commands that need to read or write files as the lockss user will be run as the lockss user.\n\nTo run a command in this context, simply type the command listed in the manual. Depending on your system's sudo configuration, you may be prompted for the user's sudo password.\n\n1 Depending on your system's sudo configuration, you may be prompted for the user's sudo password.\n8.3 Running Commands as the lockss User\n\nUnless otherwise noted, most commands in this manual are intended to be run as the lockss user (oftentimes in the lockss user's lockss-installer directory). This section describes two methods for doing so.\n\n8.3.1 Running Commands as lockss With sudo\n\nIf you are logged in as a user who can run commands as lockss via sudo:\n\n- You can start a Bash shell session as the lockss user and run any number of commands in it:\n 1. Run this command:\\footnote{Depending on your system’s sudo configuration, you may be prompted for the user’s sudo password.}\n \\begin{verbatim}\n sudo -i -u lockss\n \\end{verbatim}\n Tip: You can also use the slightly shorter version sudo -iu lockss.\n\n 2. Run commands as they are listed in the manual, for example scripts/start-lockss --wait.\n 3. When you are done, exit the lockss shell session by typing exit or logout or hitting Ctrl + D.\n\n- Alternatively, you can use sudo to run a single command as the lockss user.\n Add the following in front of the command listed in the manual:\\footnote{Page 62, 1:}\n \\begin{verbatim}\n sudo -u lockss ...\n \\end{verbatim}\n For example, if the command listed in the manual is scripts/start-lockss --wait, you would type sudo -u lockss scripts/start-lockss --wait.\n\n8.3.2 Running Commands as lockss With su\n\nIf you are logged in as root but your system does not have sudo (or does not let root use sudo), you can use su instead:\n\n- You can use su to start a Bash shell session as the lockss user and run any number of commands in it:\n 1. Type this command:\n \\begin{verbatim}\n su lockss\n \\end{verbatim}\n\n 2. Run commands as they are listed in the manual, for example scripts/start-lockss --wait.\n 3. When you are done, exit the lockss shell session by typing exit or logout or hitting Ctrl + D.\n\n- Alternatively, you can use su to run a single command as the lockss user:\n Put the command listed in the manual in quotation marks in the following way:\n \\begin{verbatim}\n su -c '...' lockss\n \\end{verbatim}\n For example, if the command to be run as the lockss user is scripts/start-lockss --wait, you would type su -c 'scripts/start-lockss --wait' lockss.\n**Caution:** You will need to take care if the command itself contains quotation marks\\(^2\\).\n\n## 8.4 Operating System Updates\n\nYou will want to update your Linux operating system at different times:\n\n- **Before Upgrading From LOCKSS 2.0-alpha6.**\n- **Before Installing the LOCKSS System** for the first time.\n- **When security-related updates are released** for the Linux kernel (which requires rebooting the machine) or other installed software packages.\n\nYour system may be set up for automatic updates or your system administrator may have policies for which packages can be updated and when.\n\nIf you wish to update software packages manually, select your operating system below and follow the instructions as **root**\\(^1\\):\n\n### AlmaLinux OS\n\nTo manually update software packages, run this **dnf** command as **root**:\n\n```bash\ndnf update\n```\n\n### Arch Linux\n\nTo manually update software packages, run this **pacman** command as **root**:\n\n```bash\npacman --sync --refresh --sysupgrade\n```\n\nor equivalently:\n\n```bash\npacman -Syu\n```\n\n### CentOS\n\n### CentOS Stream\n\nTo manually update software packages, run this **dnf** command as **root**:\n\n```bash\ndnf update\n```\n\n\\(^1\\) See *Running Commands as root*.\n\n\\(^2\\) If the command contains quotation marks, use `-c \"...\"` instead of `-c '...'`, and add a backslash in front of each double quotation mark in the command (`\\\"` instead of `\"`). Single quotation marks in the command are unchanged.\nCentOS 7\nTo manually update software packages, run this `yum` command as `root`:\n\n```\nyum update\n```\n\nDebian\nTo manually update software packages, run these `apt` commands as `root`:\n\n```\napt update\napt upgrade\n```\n\nEuroLinux\n\n**EuroLinux 8**\nTo manually update software packages, run this `dnf` command as `root`:\n\n```\ndnf update\n```\n\n**EuroLinux 7**\nTo manually update software packages, run this `yum` command as `root`:\n\n```\nyum update\n```\n\nFedora Linux\nTo manually update software packages, run this `dnf` command as `root`:\n\n```\ndnf update\n```\n\nLinux Mint\nTo manually update software packages, run these `apt` commands as `root`:\n\n```\napt update\napt upgrade\n```\nOpenSUSE\n\nOpenSUSE Tumbleweed\n\nTo manually update software packages, run these zypper commands as root:\n\n```bash\nzypper refresh\nzypper update\n```\n\nOpenSUSE Leap\n\nTo manually update software packages, run these zypper commands as root:\n\n```bash\nzypper refresh\nzypper update\n```\n\nOracle Linux\n\nOracle Linux 8-9\n\nTo manually update software packages, run this dnf command as root:\n\n```bash\ndnf update\n```\n\nOracle Linux 7\n\nTo manually update software packages, run this yum command as root:\n\n```bash\nyum update\n```\n\nRHEL\n\nRHEL 8-9\n\nTo manually update software packages, run this dnf command as root:\n\n```bash\ndnf update\n```\nRHEL 7\n\nTo manually update software packages, run this `yum` command as `root`:\n\n```\nyum update\n```\n\nRocky Linux\n\nTo manually update software packages, run this `dnf` command as `root`:\n\n```\ndnf update\n```\n\nScientific Linux\n\nTo manually update software packages, run this `yum` command as `root`:\n\n```\nyum update\n```\n\nUbuntu\n\nTo manually update software packages, run these `apt` commands as `root`:\n\n```\napt update\napt upgrade\n```\n\n8.5 Installing Curl\n\n*Downloading the LOCKSS Installer* requires *Curl*, *Wget* or *HTTPie*. Most typical Linux systems have at least one installed by default. You can check by typing `curl --version`, `wget --version` or `http --version`, and seeing which ones do not output an error message.\n\nThis section describes how to install *Curl* if necessary.\n\nSelect your operating system below and follow the instructions as `root`¹:\n\nAlmaLinux OS\n\nTo install Curl with Dnf, run this command (as `root`):\n\n```\ndnf --assumeyes install curl\n```\n\nor equivalently:\n\n```\ndnf -y install curl\n```\n\n¹ See *Running Commands as root*.\n**Arch Linux**\n\nTo install Curl with Pacman, run this command (as `root`):\n\n```\npacman --sync --noconfirm curl\n```\n\nor equivalently:\n\n```\npacman -S --noconfirm curl\n```\n\n**CentOS**\n\n**CentOS Stream**\n\nTo install Curl with Dnf, run this command (as `root`):\n\n```\ndnf --assumeyes install curl\n```\n\nor equivalently:\n\n```\ndnf -y install curl\n```\n\n**CentOS 7**\n\nTo install Curl with Yum, run this command (as `root`):\n\n```\nyum --assumeyes install curl\n```\n\nor equivalently:\n\n```\nyum -y install curl\n```\n\n**Debian**\n\nTo install Curl with Apt, follow these steps (as `root`):\n\n1. Run this `apt` command:\n \n ```\n apt update\n ```\n\n2. Run this `apt` command:\n \n ```\n apt install --assume-yes curl\n ```\n\n or equivalently:\n\n ```\n apt -y install curl\n ```\nEuroLinux\n\nEuroLinux 8-9\n\nTo install Curl with Dnf, run this command (as root):\n\ndnf --assumeyes install curl\n\nor equivalently:\n\ndnf -y install curl\n\nEuroLinux 7\n\nTo install Curl with Yum, run this command (as root):\n\nyum --assumeyes install curl\n\nor equivalently:\n\nyum -y install curl\n\nFedora Linux\n\nTo install Curl with Dnf, run this command (as root):\n\ndnf --assumeyes install curl\n\nor equivalently:\n\ndnf -y install curl\n\nLinux Mint\n\nTo install Curl with Apt, follow these steps (as root):\n\n1. Run this **apt** command:\n\n ```\n apt update\n ```\n\n2. Run this **apt** command:\n\n ```\n apt install --assume-yes curl\n ```\n\n or equivalently:\n\n ```\n apt -y install curl\n ```\nOpenSUSE\n\nOpenSUSE Tumbleweed\n\nTo install Curl with Zypper, follow these steps (as root):\n\n1. Run this `zypper` command:\n ```\n zypper refresh\n ```\n\n2. Run this `zypper` command:\n ```\n zypper --non-interactive install curl\n ```\n or equivalently:\n ```\n zypper -n install curl\n ```\n\nOpenSUSE Leap\n\nTo install Curl with Zypper, follow these steps (as root):\n\n1. Run this `zypper` command:\n ```\n zypper refresh\n ```\n\n2. Run this `zypper` command:\n ```\n zypper --non-interactive install curl\n ```\n or equivalently:\n ```\n zypper -n install curl\n ```\n\nOracle Linux\n\nOracle Linux 8-9\n\nTo install Curl with Dnf, run this command (as root):\n\n```\n dnf --assumeyes install curl\n```\n\nor equivalently:\n\n```\n dnf -y install curl\n```\nOracle Linux 7\n\nTo install Curl with Yum, run this command (as root):\n\n```bash\nyum --assumeyes install curl\n```\n\nor equivalently:\n\n```bash\nyum -y install curl\n```\n\nRHEL\n\nRHEL 8-9\n\nTo install Curl with Dnf, run this command (as root):\n\n```bash\ndnf --assumeyes install curl\n```\n\nor equivalently:\n\n```bash\ndnf -y install curl\n```\n\nRHEL 7\n\nTo install Curl with Yum, run this command (as root):\n\n```bash\nyum --assumeyes install curl\n```\n\nor equivalently:\n\n```bash\nyum -y install curl\n```\n\nRocky Linux\n\nTo install Curl with Dnf, run this command (as root):\n\n```bash\ndnf --assumeyes install curl\n```\n\nor equivalently:\n\n```bash\ndnf -y install curl\n```\nScientific Linux\n\nTo install Curl with Yum, run this command (as root):\n\n```\nyum --assumeyes install curl\n```\n\nor equivalently:\n\n```\nyum -y install curl\n```\n\nUbuntu\n\nTo install Curl with Apt, follow these steps (as root):\n\n1. Run this `apt` command:\n\n ```\n apt update\n ```\n\n2. Run this `apt` command:\n\n ```\n apt install --assume-yes curl\n ```\n\n or equivalently:\n\n ```\n apt -y install curl\n ```\n\n8.6 Installing HTTPie\n\n`Downloading the LOCKSS Installer` requires Curl, Wget or HTTPie. Most typical Linux systems have at least one installed by default. You can check by typing `curl --version`, `wget --version` or `http --version`, and seeing which ones do not output an error message.\n\nThis section describes how to install HTTPie if necessary.\n\nSelect your operating system below and follow the instructions as root\\(^1\\):\n\n**AlmaLinux OS**\n\nTo install HTTPie with Dnf, run this command (as root):\n\n```\ndnf --assumeyes install httpie\n```\n\nor equivalently:\n\n```\ndnf -y install httpie\n```\n\n---\n\n\\(^1\\) See *Running Commands as root*. \nArch Linux\n\nTo install HTTPie with Pacman, run this command (as root):\n\n```\npacman --sync --noconfirm httpie\n```\n\nor equivalently:\n\n```\npacman -S --noconfirm httpie\n```\n\nCentOS\n\nCentOS Stream\n\nTo install HTTPie with Dnf, run this command (as root):\n\n```\ndnf --assumeyes install httpie\n```\n\nor equivalently:\n\n```\ndnf -y install httpie\n```\n\nCentOS 7\n\nTo install HTTPie with Yum, run this command (as root):\n\n```\nyum --assumeyes install httpie\n```\n\nor equivalently:\n\n```\nyum -y install httpie\n```\n\nDebian\n\nTo install HTTPie with Apt, follow these instructions (as root):\n\n1. Run this `apt` command:\n\n ```\n apt update\n ```\n\n2. Run this `apt` command:\n\n ```\n apt install --assume-yes httpie\n ```\n\nor equivalently:\n\n```\napt -y install httpie\n```\nEuroLinux\n\nEuroLinux 8-9\n\nTo install HTTPie with Dnf, run this command (as root):\n\n```bash\ndnf --assumeyes install httpie\n```\n\nor equivalently:\n\n```bash\ndnf -y install httpie\n```\n\nEuroLinux 7\n\nTo install HTTPie with Yum, run this command (as root):\n\n```bash\nyum --assumeyes install httpie\n```\n\nor equivalently:\n\n```bash\nyum -y install httpie\n```\n\nFedora Linux\n\nTo install HTTPie with Dnf, run this command (as root):\n\n```bash\ndnf --assumeyes install httpie\n```\n\nor equivalently:\n\n```bash\ndnf -y install httpie\n```\n\nLinux Mint\n\nTo install HTTPie with Apt, follow these instructions (as root):\n\n1. Run this `apt` command:\n\n ```bash\n apt update\n ```\n\n2. Run this `apt` command:\n\n ```bash\n apt install --assume-yes httpie\n ```\n\n or equivalently:\n\n ```bash\n apt -y install httpie\n ```\nOpenSUSE\n\nOpenSUSE Tumbleweed\n\nTo install HTTPie with Zypper, run these commands (as root):\n\n1. Run this `zypper` command:\n ```\n zypper refresh\n ```\n\n2. Run this `zypper` command:\n ```\n zypper --non-interactive install httpie\n ```\n or equivalently:\n ```\n zypper -n install httpie\n ```\n\nOpenSUSE Leap\n\nTo install HTTPie with Zypper, run these commands (as root):\n\n1. Run this `zypper` command:\n ```\n zypper refresh\n ```\n\n2. Run this `zypper` command:\n ```\n zypper --non-interactive install httpie\n ```\n or equivalently:\n ```\n zypper -n install httpie\n ```\n\nOracle Linux\n\nOracle Linux 8-9\n\nTo install HTTPie with Dnf, run this command (as root):\n\n```\nDNF --assumeyes install httpie\n```\n\nor equivalently:\n\n```\nDNF -y install httpie\n```\n**Oracle Linux 7**\n\nTo install HTTPie with Yum, run this command (as `root`):\n\n```\nyum --assumeyes install httpie\n```\n\nor equivalently:\n\n```\nyum -y install httpie\n```\n\n**RHEL**\n\n**RHEL 8-9**\n\nTo install HTTPie with Dnf, run this command (as `root`):\n\n```\ndnf --assumeyes install httpie\n```\n\nor equivalently:\n\n```\ndnf -y install httpie\n```\n\n**RHEL 7**\n\nTo install HTTPie with Yum, run this command (as `root`):\n\n```\nyum --assumeyes install httpie\n```\n\nor equivalently:\n\n```\nyum -y install httpie\n```\n\n**Rocky Linux**\n\nTo install HTTPie with Dnf, run this command (as `root`):\n\n```\ndnf --assumeyes install httpie\n```\n\nor equivalently:\n\n```\ndnf -y install httpie\n```\n\n8.6. Installing HTTPie\nScientific Linux\n\nTo install HTTPie with Yum, run this command (as root):\n\n```\n$ yum --assumeyes install httpie\n```\n\nor equivalently:\n\n```\n$ yum -y install httpie\n```\n\nUbuntu\n\nTo install HTTPie with Apt, follow these instructions (as root):\n\n1. Run this `apt` command:\n\n ```\n $ apt update\n ```\n\n2. Run this `apt` command:\n\n ```\n $ apt install --assume-yes httpie\n ```\n\n or equivalently:\n\n ```\n $ apt -y install httpie\n ```\n\n8.7 Installing Wget\n\n*Downloading the LOCKSS Installer* requires Curl, Wget or HTTPie. Most typical Linux systems have at least one installed by default. You can check by typing `curl --version`, `wget --version` or `http --version`, and seeing which ones do not output an error message.\n\nThis section describes how to install Wget if necessary.\n\nSelect your operating system below and follow the instructions as root:\n\n**AlmaLinux OS**\n\nTo install Wget with Dnf, run this command (as root):\n\n```\n$ dnf --assumeyes install wget\n```\n\nor equivalently:\n\n```\n$ dnf -y install wget\n```\n\n[^1]: See *Running Commands as root*. \n\n---\n\nChapter 8. System Administration Tasks\n\n---\n**Arch Linux**\n\nTo install Wget with Pacman, run this command (as root):\n\n```\npacman --sync --noconfirm wget\n```\n\nor equivalently:\n\n```\npacman -S --noconfirm wget\n```\n\n**CentOS**\n\n**CentOS Stream**\n\nTo install Wget with Dnf, run this command (as root):\n\n```\ndnf --assumeyes install wget\n```\n\nor equivalently:\n\n```\ndnf -y install wget\n```\n\n**CentOS 7**\n\nTo install Wget with Yum, run this command (as root):\n\n```\nyum --assumeyes install wget\n```\n\nor equivalently:\n\n```\nyum -y install wget\n```\n\n**Debian**\n\nTo install Wget with APT, follow these steps (as root):\n\n1. Run this **`apt`** command:\n\n `apt update`\n\n2. Run this **`apt`** command:\n\n `apt install --assume-yes wget`\n\n or equivalently:\n\n `apt -y install wget`\n**EuroLinux**\n\n**EuroLinux 8**\n\nTo install Wget with Dnf, run this command (as root):\n\n```bash\ndnf --assumeyes install wget\n```\n\nor equivalently:\n\n```bash\ndnf -y install wget\n```\n\n**EuroLinux 7**\n\nTo install Wget with Yum, run this command (as root):\n\n```bash\nyum --assumeyes install wget\n```\n\nor equivalently:\n\n```bash\nyum -y install wget\n```\n\n**Fedora Linux**\n\nTo install Wget with Dnf, run this command (as root):\n\n```bash\ndnf --assumeyes install wget\n```\n\nor equivalently:\n\n```bash\ndnf -y install wget\n```\n\n**Linux Mint**\n\nTo install Wget with Apt, follow these steps (as root):\n\n1. Run this `apt` command:\n\n ```bash\n apt update\n ```\n\n2. Run this `apt` command:\n\n ```bash\n apt install --assume-yes wget\n ```\n\n or equivalently:\n\n ```bash\n apt -y install wget\n ```\nOpenSUSE\n\nOpenSUSE Tumbleweed\n\nTo install Wget with Zypper, run these commands (as root):\n\n1. Run this `zypper` command:\n\n ```\n zypper refresh\n ```\n\n2. Run this `zypper` command:\n\n ```\n zypper --non-interactive install wget\n ```\n\n or equivalently:\n\n ```\n zypper -n install wget\n ```\n\nOpenSUSE Leap\n\nTo install Wget with Zypper, run these commands (as root):\n\n1. Run this `zypper` command:\n\n ```\n zypper refresh\n ```\n\n2. Run this `zypper` command:\n\n ```\n zypper --non-interactive install wget\n ```\n\n or equivalently:\n\n ```\n zypper -n install wget\n ```\n\nOracle Linux\n\nOracle Linux 8-9\n\nTo install Wget with Dnf, run this command (as root):\n\n```\ndnf --assumeyes install wget\n```\n\nor equivalently:\n\n```\ndnf -y install wget\n```\nOracle Linux 7\n\nTo install Wget with Yum, run this command (as root):\n\n```\nyum --assumeyes install wget\n```\n\nor equivalently:\n\n```\nyum -y install wget\n```\n\nRHEL\n\nRHEL 8-9\n\nTo install Wget with Dnf, run this command (as root):\n\n```\ndnf --assumeyes install wget\n```\n\nor equivalently:\n\n```\ndnf -y install wget\n```\n\nRHEL 7\n\nTo install Wget with Yum, run this command (as root):\n\n```\nyum --assumeyes install wget\n```\n\nor equivalently:\n\n```\nyum -y install wget\n```\n\nRocky Linux\n\nTo install Wget with Dnf, run this command (as root):\n\n```\ndnf --assumeyes install wget\n```\n\nor equivalently:\n\n```\ndnf -y install wget\n```\n**Scientific Linux**\n\nTo install Wget with Yum, run this command (as root):\n\n```\nyum --assumeyes install wget\n```\n\nor equivalently:\n\n```\nyum -y install wget\n```\n\n**Ubuntu**\n\nTo install Wget with Apt, follow these steps (as root):\n\n1. Run this `apt` command:\n\n ```\n apt update\n ```\n\n2. Run this `apt` command:\n\n ```\n apt install --assume-yes wget\n ```\n\n or equivalently:\n\n ```\n apt -y install wget\n ```\n\n---\n\n**8.8 Resetting the System to a Blank State**\n\n**During and after alpha and beta testing**, you may have cause to delete all of the stored content in order to start over. This section provides guidance on how to do this without reinstalling completely from scratch.\n\nLOCKSS 2.x stores content and metadata in several places which depend on how it was configured. We've provided a script to facilitate deleting all the right directories, but to provide flexibility and make it difficult to do this accidentally, the script generates a second script that actually performs the deletions.\n\nThe procedure consists of deleting the PostgreSQL data directory (`lockss-stack-postgres-data`) and Solr data directory (`lockss-stack-solr-data`) from the primary content data storage area, and the repository data directory (`lockss-stack-repo-data`) from each content data storage area, all of which must be done after shutting down the system.\n\n**Directions**\n\n1. Stop the stack:\n\n ```\n scripts/stop-lockss\n ```\n\n2. Generate the deletion script:\n\n ```\n scripts/upgrades/generate-content-reset-script > /tmp/delcontent\n ```\n\n3. Examine `/tmp/delcontent` if you wish. Note that there is one `sudo` command because the PostgreSQL files are not owned by the `lockss` user, which may need modifying in some environments.\n4. Make the script executable:\n\n```\nchmod +x /tmp/delcontent\n```\n\n5. Delete the content:\n\n```\n/tmp/delcontent\n```\n\n6. We recommend deleting the script after use:\n\n```\nrm /tmp/delcontent\n```\n\n7. Restart the system:\n\n```\nscripts/start-lockss\n```\nThis appendix contains pages of additional information about the LOCKSS system. Sections include security advisories; reference information such as list of ports or component versions; and advanced topics like running the LCAP polling and repair protocol over SSL, working with PostgreSQL, or running the LOCKSS Installer from Git.\n\n9.1 Security Advisories\n\nThere are no security advisories currently published for LOCKSS 2.0-alpha7. See also the LOCKSS Documentation Portal's Security pages.\n\n9.2 Release Notes\n\n9.2.1 LOCKSS 2.0.70-alpha7\n\nReleased: NOT YET RELEASED\n\nLOCKSS 2.0.70-alpha7 is the first release of the LOCKSS 2.0-alpha7 system.\n\nRelease Notes\n\nFIXME (insert release notes here)\n\nComponent Versions\n\nLOCKSS 2.0.70-alpha7 consists of a configurable set of the following components:\n\n- LOCKSS Installer version 2.0.70-alpha7\n- LOCKSS Repository Service version 2.14.0\n- LOCKSS Configuration Service version 2.8.0\n- LOCKSS Poller Service version 2.6.0\n- LOCKSS Metadata Extraction Service version 2.7.0\n- LOCKSS Metadata Service version 2.4.0\n- LOCKSS SOAP Compatibility Service version 1.4.0\n9.3 Frequently Asked Questions\n\nThis section answers some common questions about the LOCKSS system.\n\nI have an existing classic LOCKSS system (version 1.x). Can I upgrade to LOCKSS 2.0-alpha7?\n\nFIXME (beta is less tentative than alpha)\n\nThe LOCKSS 2.0-alpha7 release is a technology preview which we are excited to share with the community for testing purposes. It is not yet possible to convert from a classic LOCKSS system (e.g. version 1.76.5) to a LOCKSS 2.0 system for production purposes.\n\nHowever, version 1.76 of the classic LOCKSS system contains a prototype tool to test the migration of archival units (AUs) from a production 1.76 system to a test 2.0-alpha7 system, for testing purposes. See https://github.com/lockss/community/wiki/Migration-Tool.\n\nTo help us advance toward the final LOCKSS 2.0 release, please consider installing and running the LOCKSS 2.0-alpha7 release on a test machine and providing us with your feedback.\n\nI have a LOCKSS system running 2.0-alpha6. Can I upgrade to LOCKSS 2.0-alpha7?\n\nYes. You are welcome to wipe your testing data from LOCKSS 2.0-alpha6 and start from scratch, but there is an upgrade path from LOCKSS 2.0-alpha6.\n\nCan I use my own PostgreSQL database? Can I use my own Solr database?\n\nYes, you can configure the system to use your institution's Postgres database and/or Solr database -- or you can simply let system run included ones locally.\n\nCan I replay Web content with my own Pywb instance? Can I replay Web content with my own OpenWayback instance?\n\nYes, you can configure your own Pywb instance and/or OpenWayback instance to connect directly to the LOCKSS Repository Service -- or you can let the system run included ones locally, or you can choose not to run any Web replay engine at all.\n\n9.4 Software License\n\nThe LOCKSS system is made available under the terms of the 3-Clause BSD License, a permissive open-source license.\n\nCopyright (c) 2000-2022, Board of Trustees of Leland Stanford Jr. University\n\nRedistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:\n\n1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.\n\n2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.\n\n(continues on next page)\n3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.\n\nTHIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS \"AS IS\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\n\nFor more information, visit the Software License page on the LOCKSS Web site.\n\n### 9.5 Network Ports\n\nThis section describes the default network ports used by the LOCKSS system.\n\nUnless otherwise noted, all ports are **TCP**.\n\nAll ports are in the 24600-24699 range, except the LCAP (LOCKSS polling and repair) port which retains its historical value of 9729, and the OpenWayback port which is 8080.\n### 9.6 Downloading the LOCKSS Installer using git\n\n**Warning:** The official way to download the LOCKSS Installer is now through the LOCKSS Downloader, rather than cloning the LOCKSS Installer as a Git project as in previous releases.\n\nFollow the instructions in *Installing the LOCKSS System* to use the LOCKSS Downloader.\n\n**Tip:** Follow the instructions in `/appendix/git` to install `git`, if it is not yet available on your system.\n\nFollow these instructions as the `lockss` user\\(^1\\):\n\n1. If you have not previously cloned the LOCKSS Installer, run this command to clone it from GitHub:\n\n ```\ngit clone https://github.com/lockss/lockss-installer\n ```\n\n---\n\n**Troubleshooting**\n\n\\(^1\\) See *Running Commands as the lockss User*\nOn early CentOS 7 systems (for example CentOS 7.1), you may receive the error message fatal: unable to access 'https://github.com/lockss/lockss-installer/': Peer reports incompatible or unsupported protocol version. This is due to outdated network security libraries. Run the command `yum update -y curl nss nss-util nspr` as root to update them, and retry the `git clone` command.\n\n**Tip:** To avoid a harmless Git warning when updating the LOCKSS Installer from GitHub in the future, run this command within the `lockss-installer` directory created by the `git clone` command:\n\n```bash\ngit config --local pull.rebase true\n```\n\n2. Checkout the 2.0-alpha5 branch of the LOCKSS Installer by running this command within the `lockss-installer` directory created by the `git clone` command earlier:\n\n```bash\ngit checkout 2.0-alpha5\n```\n\n### 9.7 Working with PostgreSQL\n\nThis section of the appendix documents administrative tasks for the embedded PostgreSQL database configured by the LOCKSS 2.x system.\n\n#### 9.7.1 Changing the PostgreSQL Database Password\n\nTo change the password of the embedded PostgreSQL database, perform the following steps as the `lockss` user in the `lockss-installer` directory:\n\n1. Ensure the Kubernetes service definitions reflect the current state of the LOCKSS configuration by running:\n\n ```bash\n scripts/assemble-lockss\n ```\n\n2. Start the PostgreSQL database container by running:\n\n ```bash\n k3s kubectl apply -n lockss --filename=config/configs/lockss-stack/svcs/lockss--postgres-service.yaml\n ```\n\n3. Run the following command to store the name of the PostgreSQL database container into the variable `postgres_pod`:\n\n ```bash\n postgres_pod=$(k3s kubectl get pod -n lockss --selector=io.kompose.service=lockss--postgres-service --output=jsonpath=\"{.items[0].metadata.name}\")\n ```\n\n4. Run the following command to store the IP of the PostgreSQL database container into the variable `postgres_ip`:\n\n ```bash\n postgres_ip=$(k3s kubectl get pod -n lockss --selector=io.kompose.service=lockss--postgres-service --output=jsonpath=\"{.items[0].status.podIP}\")\n ```\n\n5. Execute the following command to alter the LOCKSS database user's password, taking care to replace `newpassword` with your new embedded PostgreSQL database password:\n\n ```bash\n [lockss]\n ```\n\n---\n\n1 See *Running Commands as the lockss User*. \n\n---\n6. To verify that the password change worked, run the following command:\n\n```bash\nek3s kubectl exec $postgres_pod -n lockss -it -- psql --username=LOCKSS --dbname=postgres --host=$postgres_ip\n```\n\nand enter `newpassword` at the `Password for user LOCKSS` prompt. If the password change was successful and you enter `newpassword` correctly, you will see a PostgreSQL prompt similar to:\n\n```\npsql (9.6.12)\nType \"help\" for help.\n```\n\nwhich you can exit by entering `q` or hitting `Ctrl + D`. If the password change was unsuccessful or you do not enter `newpassword` correctly, you will see output similar to:\n\n```\npsql: FATAL: password authentication failed for user \"LOCKSS\"\ncommand terminated with exit code 2\n```\n\n7. Stop the PostgreSQL database container by running this command:\n\n```bash\nk3s kubectl -n lockss delete service,deployment lockss-postgres-service && k3s kubectl -n lockss wait --for=delete pod $postgres_pod --timeout=60s\n```\n\n8. Re-run `configure-lockss` so that you can record the new embedded PostgreSQL database password into the configuration of the LOCKSS stack:\n\n```bash\nscripts/configure-lockss\n```\n\nSee the PostgreSQL and Embedded PostgreSQL Database sections of Configuring the LOCKSS System for details.\n\n## 9.8 LCAP Over SSL\n\nThe section explains how to configure secure communication between LOCKSS boxes in a network.\n\nSome LOCKSS networks, such as the Global LOCKSS Network (GLN), are open, in the sense that anyone may join and set up a LOCKSS box to participate in that network. The LOCKSS polling protocol (LCAP) includes several security measures to prevent rogue players from disrupting the network, but it is also possible to create a closed network, where only authorized nodes are allowed to participate. This document describes the steps needed to set up such a network.\n\nIn order to ensure that only authorized nodes may participate, each node is issued a private key, and all nodes are provided the set of corresponding public keys. This allows all inter-node communication to be both encrypted and authenticated, using SSL.\n\n**Note:** The Classic LOCKSS system (version 1.x) does not support PKCS12, so if building keystores for a network that includes classic LOCKSS nodes, JCEKS should be selected.\n9.8.1 Generating Keystores\n\nThe authority in charge of the private LOCKSS network (PLN) must create and distribute Java keystores to all participants. Each box receives two keystores: one containing its own private key (along with a password file containing the secret password for the private key) and another containing the public certificates for each of the boxes in the network. There are two methods available to create these keystores:\n\n- A Command Line Tool run in the LOCKSS development environment.\n- An Interactive Tool invoked in a running LOCKSS node.\n\nIn both cases, the admin creating the keystores must know the complete set of hostnames of boxes in the network. More hosts can be added at any time, but a new public keystore must be created and distributed to each box.\n\n**Command Line Tool**\n\nTo use the command line tool:\n\n1. Clone the lockss-core and laaws-dev-scripts projects from GitHub, in sibling directories.\n2. Build lockss-core.\n3. In the root directory of lockss-core, run this command:\n\n ```bash\n ../laaws-dev-scripts/bin/runclass org.lockss.keystore.EditKeyStores -s pubkeystore.\n pkcs12 -o keydir box1.pln.org ... boxN.pln.org\n ```\n\n This will create, in the directory keydir, a public keystore named pubkeystore.pkcs12, and a pair of files boxK.pln.org.pkcs12 and boxK.pln.org.pass for each one of the N host names box1.pln.org through boxN.pln.org.\n\n4. To add additional hosts, provide the existing public keystore as the value of the -s argument, and list the new hosts. The new public keys will be added to the existing public keystore.\n\n**Interactive Tool**\n\n1. Bring up a LOCKSS stack, either in the production environment or runcluster. In the UI, select DebugPanel → Generate LCAP Keys.\n2. Enter the hostname of each of the LOCKSS boxes in the Hostnames text box, then click the Generate Keystores button. A .tgz or a .zip file will be generated and offered for download. This file will contain the private keystore and password file for each host, as well as the shared public keystore.\n3. To add additional hosts, use the Browse button to supply the existing public keystore, and enter the new hosts in the Hostnames text box. The downloaded file will contain the private keystore and password files for each new host, as well as the updated shared public keystore, which must be installed on all hosts.\n9.8.2 Installing the Keystores\n\n1. **Securely** transmit to each box its two files and the public keystore. Put them in ~lockss/lockss-installer/config/keys, and set the owner and group to lockss:lockss and the permissions to 600.\n\n2. Restart the stack and check that it is now using SSL. In the UI, select *Daemon Status* → *Comm Channels*. The page should show *SSL: TLSv1.2, Client Auth*.\n\n3. After a few hours, select *Daemon Status* → *Comm Peer Data* to ensure that each box is successfully originating and accepting connections from all the other boxes."}}},{"rowIdx":89,"cells":{"id":{"kind":"string","value":"b44321ea31b15527f6770b4b22337055b4e7dfca"},"text":{"kind":"string","value":"On Polymorphic Sessions and Functions\nA Tale of Two (Fully Abstract) Encodings\n\nBernardo Toninho and Nobuko Yoshida\nDepartment of Computing, Imperial College London, United Kingdom\n\nAbstract. This work exploits the logical foundation of session types to\ndetermine what kind of type discipline for the π-calculus can exactly\ncapture, and is captured by, λ-calculus behaviours. Leveraging the proof\ntheoretic content of the soundness and completeness of sequent calculus\nand natural deduction presentations of linear logic, we develop the first\nmutually inverse and fully abstract processes-as-functions and functions-\nas-processes encodings between a polymorphic session π-calculus and a\nlinear formulation of System F. We are then able to derive results of\nthe session calculus from the theory of the λ-calculus: (1) we obtain\na characterisation of inductive and coinductive session types via their\nalgebraic representations in System F; and (2) we extend our results to\naccount for value and process passing, entailing strong normalisation.\n\n1 Introduction\n\nDating back to Milner’s seminal work [29], encodings of λ-calculus into π-calculus\nare seen as essential benchmarks to examine expressiveness of various extensions\nof the π-calculus. Milner’s original motivation was to demonstrate the power of\nlink mobility by decomposing higher-order computations into pure name pass-\ning. Another goal was to analyse functional behaviours in a broad computational\nuniverse of concurrency and non-determinism. While operationally correct en-\ncodings of many higher-order constructs exist, it is challenging to obtain encod-\nings that are precise wrt behavioural equivalence: the semantic distance between\nthe λ-calculus and the π-calculus typically requires either restricting process be-\nhaviours [15] (e.g. via typed equivalences [5]) or enriching the λ-calculus with\nconstants that allow for a suitable characterisation of the term equivalence\ninduced by the behavioural equivalence on processes [43].\n\nEncodings in π-calculi also gave rise to new typing disciplines: Session types\n[20][22], a typing system that is able to ensure deadlock-freedom for commu-\nnication protocols between two or more parties [23], were originally motivated\n“from process encodings of various data structures in an asynchronous version of\nthe π-calculus” [21]. Recently, a propositions-as-types correspondence between\nlinear logic and session types [59][51] has produced several new developments\nand logically-motivated techniques [19][21][7][20] to augment both the theory and\npractice of session-based message-passing concurrency. Notably, parametric ses-\nsion polymorphism [7] (in the sense of Reynolds [41]) has been proposed and a\ncorresponding abstraction theorem has been shown.\nOur work expands upon the proof theoretic consequences of this propositions-as-types correspondence to address the problem of how to exactly match the behaviours induced by session $\\pi$-calculus encodings of the $\\lambda$-calculus with those of the $\\lambda$-calculus. We develop mutually inverse and fully abstract encodings (up to typed observational congruences) between a polymorphic session-typed $\\pi$-calculus and the polymorphic $\\lambda$-calculus. The encodings arise from the proof theoretic content of the equivalence between sequent calculus (i.e. the session calculus) and natural deduction (i.e. the $\\lambda$-calculus) for second-order intuitionistic linear logic, greatly generalising [49]. While fully abstract encodings between $\\lambda$-calculi and $\\pi$-calculi have been proposed (e.g. [5,43]), our work is the first to consider a two-way, both mutually inverse and fully abstract embedding between the two calculi by crucially exploiting the linear logic-based session discipline. This also sheds some definitive light on the nature of concurrency in the (logical) session calculi, which exhibit “don’t care” forms of non-determinism (e.g. processes may race on stateless replicated servers) rather than “don’t know” non-determinism (which requires less harmonious logical features [2]).\n\nIn the spirit of Gentzen [14], we use our encodings as a tool to study non-trivial properties of the session calculus, deriving them from results in the $\\lambda$-calculus: We show the existence of inductive and coinductive sessions in the polymorphic session calculus by considering the representation of initial $F$-algebras and final $F$-coalgebras [28] in the polymorphic $\\lambda$-calculus [119] (in a linear setting [6]). By appealing to full abstraction, we are able to derive processes that satisfy the necessary algebraic properties and thus form adequate uniform representations of inductive and coinductive session types. The derived algebraic properties enable us to reason about standard data structure examples, providing a logical justification to typed variations of the representations in [30].\n\nWe systematically extend our results to a session calculus with $\\lambda$-term and process passing (the latter being the core calculus of [50], inspired by Benton’s LNL [4]). By showing that our encodings naturally adapt to this setting, we prove that it is possible to encode higher-order process passing in the first-order session calculus fully abstractly, providing a typed and proof-theoretically justified re-envisioning of Sangiorgi’s encodings of higher-order $\\pi$-calculus [46]. In addition, the encoding instantly provides a strong normalisation property of the higher-order session calculus.\n\nContributions and the outline of our paper are as follows:\n\n§ 3.1 develops a functions-as-processes encoding of a linear formulation of System F, Linear-F, using a logically motivated polymorphic session $\\pi$-calculus, Poly$\\pi$, and shows that the encoding is operationally sound and complete.\n\n§ 3.2 develops a processes-as-functions encoding of Poly$\\pi$ into Linear-F, arising from the completeness of the sequent calculus wrt natural deduction, also operationally sound and complete.\n\n§ 3.3 studies the relationship between the two encodings, establishing they are mutually inverse and fully abstract wrt typed congruence, the first two-way embedding satisfying both properties.\n§ 4 develops a faithful representation of inductive and coinductive session types in Polyπ via the encoding of initial and final (co)algebras in the polymorphic λ-calculus. We demonstrate a use of these algebraic properties via examples. § 4.2, 4.3 study term-passing and process-passing session calculi, extending our encodings to provide embeddings into the first-order session calculus. We show full abstraction and mutual inversion results, and derive strong normalisation of the higher-order session calculus from the encoding.\n\nIn order to introduce our encodings, we first overview Polyπ, its typing system and behavioural equivalence (§ 2). We discuss related work and conclude with future work (§ 5). Detailed proofs can be found in [52].\n\n2 Polymorphic Session π-Calculus\n\nThis section summarises the polymorphic session π-calculus [7], dubbed Polyπ, arising as a process assignment to second-order linear logic [15], its typing system and behavioural equivalences.\n\n2.1 Processes and Typing\n\nSyntax. Given an infinite set Λ of names x, y, z, u, v, the grammar of processes P, Q, R and session types A, B, C is defined by:\n\n\\[\n\\begin{align*}\nP, Q, R &::= x(y).P \\mid x(y).P \\mid P \\mid Q \\mid (\\nu y) P \\mid [x \\leftrightarrow y] \\mid 0 \\\\\nA, B &::= 1 \\mid A \\rightarrow B \\mid A \\otimes B \\mid A \\& B \\mid A \\oplus B \\mid !A \\mid \\forall X. A \\mid \\exists X. A \\mid X\n\\end{align*}\n\\]\n\nx(y).P denotes the output of channel y on x with continuation process P; x(y).P denotes an input along x, bound to y in P; P | Q denotes parallel composition; (νy)P denotes the restriction of name y to the scope of P; 0 denotes the inactive process; [x ↔ y] denotes the linking of the two channels x and y (implemented as renaming); x(A).P and x(Y).P denote the sending and receiving of a type A along x bound to Y in P of the receiver process; x.inl; P and x.inr; P denote the emission of a selection between the left or right branch of a receiver x.case(P, Q) process; !x(y).P denotes an input-guarded replication, that spawns replicas upon receiving an input along x. We often abbreviate (νy)x(y).P to π(x).P and omit trailing 0 processes. By convention, we range over linear channels with x, y, z and shared channels with u, v, w.\n\nThe syntax of session types is that of (intuitionistic) linear logic propositions which are assigned to channels according to their usages in processes: 1 denotes the type of a channel along which no further behaviour occurs; A → B denotes a session that waits to receive a channel of type A and will then proceed as a session of type B; dually, A ⊗ B denotes a session that sends a channel of type A and continues as B; A & B denotes a session that offers a choice between proceeding as behaviours A or B; A ⊕ B denotes a session that internally chooses to continue as either A or B, signalling appropriately to the communicating\nThe operational semantics of our calculus is presented as a standard labelled transition system (Fig. 1) in the style of the π-calculus [46].\n\nIn the remainder of this work we write $\\equiv$ for a standard π-calculus structural congruence extended with the clause $[x \\leftrightarrow y] \\equiv [y \\leftrightarrow x]$. In order to streamline the presentation of observational equivalence [36,7], we write $\\equiv$ for structural congruence extended with the so-called sharpened replication axioms [46], which capture basic equivalences of replicated processes (and are present in the proof dynamics of the exponential of linear logic). A transition $P \\xrightarrow{\\alpha} Q$ denotes that $P$ may evolve to $Q$ by performing the action represented by label $\\alpha$. An action $\\alpha$ ($\\pi$) requires a matching $\\pi$ ($\\alpha$) in the environment to enable progress. Labels include: the silent internal action $\\tau$, output and bound output actions ($x(y)$ and $(\\nu z)x(z)$); input action $x(y)$; the binary choice actions ($x.\\text{inl}$, $x.\\text{inr}$, and $x.\\text{inr}$); and output and input actions of types ($x.A$ and $x.A$).\n\nThe labelled transition relation is defined by the rules in Fig. 1 subject to the side conditions: in rule (res), we require $y \\notin \\text{fn}(\\alpha)$; in rule (par), we require $\\text{bn}(\\alpha) \\cap \\text{fn}(R) = \\emptyset$; in rule (close), we require $y \\notin \\text{fn}(Q)$. We omit the symmetric versions of (par), (com), (lout), (lin), (close) and closure under $\\alpha$-conversion. We write $\\rho_1 \\rho_2$ for the composition of relations $\\rho_1$, $\\rho_2$. We write $\\to$ to stand for $\\xrightarrow{y}$. Weak transitions are defined as usual: we write $\\Longrightarrow$ for the reflexive, transitive closure of $\\xrightarrow{y}$. Given $\\alpha \\neq \\tau$, notation $\\xrightarrow{\\alpha}$ stands for $\\xrightarrow{y}$ and $\\xrightarrow{\\tau}$ stands for $\\Longrightarrow$.\n\n**Typing System.** The typing rules of Polyπ are given in Fig. 2 following [7]. The rules define the judgment $\\Omega; \\Gamma; \\Delta \\vdash P :: z : A$, denoting that process $P$ offers a session of type $A$ along channel $z$, using the linear sessions in $\\Delta$, (potentially using the unrestricted or shared sessions in $\\Gamma$, with polymorphic type variables maintained in $\\Omega$. We use a well-formedness judgment $\\Omega \\vdash A$ type which states that $A$ is well-formed wrt the type variable environment $\\Omega$ (i.e. $\\text{fn}(A) \\subseteq \\Omega$). We often write $T$ for the right-hand side typing $z : A$, · for the empty context\nWe clarify a few of the key rules: Rule (⇒R) defines the meaning of (impredicative) universal quantification over session types, stating that a session of type ∀X.A inputs a type and then behaves uniformly as A; dually, to use such a session (rule ∀L), a process must output a type B which then warrants the use of the session as type A{B/X}. Rule ⇒R captures session input, where a session of type A ⇒ B expects to receive a session of type A which will then be used to produce a session of type B. Dually, session output (rule ⊗R) is achieved by producing a fresh session of type A (that uses a disjoint set of sessions to those of the continuation) and outputting the fresh session along z, which is then a session of type B. Linear composition is captured by rule cut which enables a process that offers a session x:A (using linear sessions in Δ1) to be composed with a process that uses that session (amongst others in Δ2) to offer z:C. As shown in [7], typing entails Subject Reduction, Global Progress, and Termination.\n\n**Observational Equivalences.** We briefly summarise the typed congruence and logical equivalence with polymorphism, giving rise to a suitable notion of relational parametricity in the sense of Reynolds [11], defined as a contextual logical relation on typed processes [7]. The logical relation is reminiscent of a typed bisimulation. However, extra care is needed to ensure well-foundedness due to impredicative type instantiation. As a consequence, the logical relation allows us to reason about process equivalences where type variables are not instantiated with the same, but rather related types.\n\n**Typed Barbed Congruence ( ≡).** We use the typed contextual congruence from [7], which preserves observable actions, called barbs. Formally, barbed congruence, noted ≡, is the largest equivalence on well-typed processes that is τ-closed, barb preserving, and contextually closed under typed contexts; see [7] and [52] for the full definition.\nLogical Equivalence \\((\\approx_L)\\). The definition of logical equivalence is no more than a typed contextual bisimulation with the following intuitive reading: given two open processes \\(P\\) and \\(Q\\) (i.e. processes with non-empty left-hand side typings), we define their equivalence by inductively closing out the context, composing with equivalent processes offering appropriately typed sessions. When processes are closed, we have a single distinguished session channel along which we can perform observations, and proceed inductively on the structure of the offered session type. We can then show that such an equivalence satisfies the necessary fundamental properties (Theorem 2.3).\n\nThe logical relation is defined using the candidates technique of Girard [16]. In this setting, an equivalence candidate is a relation on typed processes satisfying basic closure conditions: an equivalence candidate must be compatible with barbed congruence and closed under forward and converse reduction.\n\nDefinition 2.1 (Equivalence Candidate). An equivalence candidate \\(\\mathcal{R}\\) at \\(z:A\\) and \\(z:B\\), noted \\(\\mathcal{R}::z:A\\leadsto B\\), is a binary relation on processes such that, for every \\((P,Q)\\in\\mathcal{R}::z:A\\leadsto B\\) both \\(\\cdot\\vdash P::z:A\\) and \\(\\cdot\\vdash Q::z:B\\) hold, together with the following (we often write \\((P,Q)\\in\\mathcal{R}::z:A\\leadsto B\\) as \\(P\\mathcal{R}Q::z:A\\leadsto B\\)):\n\n1. If \\((P,Q)\\in\\mathcal{R}::z:A\\leadsto B\\), \\(\\cdot\\vdash P \\equiv P'::z:A\\), and \\(\\cdot\\vdash Q \\equiv Q'::z:B\\) then \\((P',Q')\\in\\mathcal{R}::z:A\\leadsto B\\).\n2. If \\((P,Q)\\in\\mathcal{R}::z:A\\leadsto B\\) then, for all \\(P_0\\) such that \\(\\cdot\\vdash P_0::z:A\\) and \\(P_0\\implies P\\), we have \\((P_0,Q)\\in\\mathcal{R}::z:A\\leadsto B\\). Symmetrically for \\(Q\\).\n\nTo define the logical relation we rely on some auxiliary notation, pertaining to the treatment of type variables arising due to impredicative polymorphism. We write \\(\\omega:\\Omega\\) to denote a mapping \\(\\omega\\) that assigns a closed type to the type variables in \\(\\Omega\\). We write \\(\\omega(X)\\) for the type mapped by \\(\\omega\\) to variable \\(X\\). Given two mappings \\(\\omega:\\Omega\\) and \\(\\omega':\\Omega\\), we define an equivalence candidate assignment \\(\\eta\\) between \\(\\omega\\) and \\(\\omega'\\) as a mapping of equivalence candidate \\(\\eta(X)::\\equiv:\\omega(X)\\leadsto \\omega'(X)\\) to the type variables in \\(\\Omega\\), where the particular choice of a distinguished right-hand side channel is delayed (i.e. to be instantiated later on). We write \\(\\eta(X)(z)\\) for the instantiation of the (delayed) candidate with the name \\(z\\). We write \\(\\omega:\\omega'\\leadsto\\omega'\\) to denote that \\(\\eta\\) is a candidate assignment between \\(\\omega\\) and \\(\\omega'\\); and \\(\\omega(P)\\) to denote the application of mapping \\(\\omega\\) to \\(P\\).\n\nWe define a sequent-indexed family of process relations, that is, a set of pairs of processes \\((P,Q)\\), written \\(\\Gamma;\\Delta\\vdash P\\equiv_L Q::\\Omega\\), satisfying some conditions, typed under \\(\\Gamma;\\Delta\\vdash T\\), with \\(\\omega:\\Omega\\) and \\(\\eta:\\omega\\equiv\\omega'\\). Logical equivalence is defined inductively on the size of the typing contexts and then on the structure of the right-hand side type. We show only select cases (see [52] for the full definition).\n\nDefinition 2.2 (Logical Equivalence). (Base Case) Given a type \\(A\\) and mappings \\(\\omega,\\omega',\\eta\\), we define logical equivalence, noted \\(P\\equiv_L Q::z:A[\\eta:\\omega\\equiv\\omega']\\), as the smallest symmetric binary relation containing all pairs of processes \\((P,Q)\\) such that (i) \\(\\cdot\\vdash \\hat{\\omega}(P)::z:\\hat{\\omega}(A)\\); (ii) \\(\\cdot\\vdash \\hat{\\omega'}(Q)::z:\\hat{\\omega'}(A)\\); and (iii) satisfies the conditions given below:\n− $P \\simeq L Q :: z : X[\\eta : \\omega \\leftrightarrow \\omega']$ iff $(P, Q) \\in \\eta (X)(z)\n− P \\simeq L Q :: z : A \\rightarrow B[\\eta : \\omega \\leftrightarrow \\omega']$ iff ∀P', y. $(P \\triangleleft (\\omega \\triangleright y) \\triangleright P') \\Rightarrow \\exists Q'. Q \\triangleleft (\\omega \\triangleright y) \\triangleright Q'$ s.t. ∀R₁, R₂, R₃ \\simeq L R₂ :: y : A[\\eta : \\omega \\leftrightarrow \\omega']| (\\nu y)(P' | R₁) \\simeq L (\\nu y)(Q' | R₂) :: z : B[\\eta : \\omega \\leftrightarrow \\omega']\n− $P \\simeq L Q :: z : A \\otimes B[\\eta : \\omega \\leftrightarrow \\omega']$ iff ∀P', y. $(P \\triangleleft \\nu y \\triangleright (\\eta \\triangleright y) \\rightarrow P') \\Rightarrow \\exists Q'. Q \\triangleleft \\nu y \\triangleright Q'$ s.t. ∃P₁, P₂, Q₁, Q₂. P' \\equiv P₁ | P₂ ∧ Q' \\equiv Q₁ | Q₂ ∧ P₁ \\simeq L Q₁ :: y : A[\\eta : \\omega \\leftrightarrow \\omega'] \\land P₂ \\simeq L Q₂ :: z : B[\\eta : \\omega \\leftrightarrow \\omega']\n− $P \\simeq L Q :: z : X.A[\\eta : \\omega \\leftrightarrow \\omega']$ iff ∀B₁, B₂, P', R ::z : B₁ \\leftrightarrow B₂. $(P \\triangleleft (B₁) \\rightarrow P')$ implies $\\exists Q'. Q \\triangleleft (B₂) \\rightarrow Q' :: z : A[\\eta[X \\mapsto R] : \\omega[X \\mapsto B₁] \\leftrightarrow \\omega'[X \\mapsto B₂]]$}\n\n(Inductive Case) Let Γ, Ω be non empty. Given $\\Omega, \\Gamma; \\Delta \\vdash P :: T$ and $\\Omega, \\Gamma; \\Delta \\vdash Q :: T$, the binary relation on processes $\\Gamma; \\Delta \\vdash P \\approx L Q :: T[\\eta : \\omega \\leftrightarrow \\omega']$ (with $\\omega, \\omega' : \\Omega$ and $\\eta : \\omega \\leftrightarrow \\omega'$) is inductively defined as:\n\n$\\Gamma, \\Delta, y : A \\vdash P \\approx L Q :: T[\\eta : \\omega \\leftrightarrow \\omega']$ iff ∀R₁, R₂, s.t. R₁ \\simeq L R₂ :: y : A[\\eta : \\omega \\leftrightarrow \\omega']$, $\\Gamma, \\Delta \\vdash (\\nu y)(\\omega(P) \\triangleright \\omega(R₁))) \\approx L (\\nu y)(\\omega'(Q) \\triangleright \\omega'(R₂))) :: T[\\eta : \\omega \\leftrightarrow \\omega']$\n\n$\\Gamma, u : A \\vdash P \\approx L Q :: T[\\eta : \\omega \\leftrightarrow \\omega']$ iff ∀R₁, R₂, s.t. R₁ \\simeq L R₂ :: y : A[\\eta : \\omega \\leftrightarrow \\omega']$, $\\Gamma, \\Delta \\vdash (\\nu u)(\\omega(P) \\triangleright \\omega(R₁))) \\approx L (\\nu u)(\\omega'(Q) \\triangleright \\omega'(R₂))) :: T[\\eta : \\omega \\leftrightarrow \\omega']$\n\nFor the sake of readability we often omit the $\\eta : \\omega \\leftrightarrow \\omega'$ portion of $\\approx L$, which is henceforth implicitly universally quantified. Thus, we write $\\Omega; \\Gamma; \\Delta \\vdash P \\approx L Q :: z : A$ (or $P \\approx L Q$) iff the two given processes are logically equivalent for all consistent instantiations of its type variables.\n\nIt is instructive to inspect the clause for type input ($\\forall X.A$): the two processes must be able to match inputs of any pair of related types (i.e. types related by a candidate), such that the continuations are related at the open type $A$ with the appropriate type variable instantiations, following Girard [16]. The power of this style of logical relation arises from a combination of the extensional flavour of the equivalence and the fact that polymorphic equivalences do not require the same type to be instantiated in both processes, but rather that the types are related (via a suitable equivalence candidate relation).\n\n**Theorem 2.3 (Properties of Logical Equivalence [7]).**\n\n**Parametricity:** If $\\Omega; \\Gamma; \\Delta \\vdash P :: z : A$ then, for all $\\omega, \\omega' : \\Omega$ and $\\eta : \\omega \\leftrightarrow \\omega'$, we have $\\Gamma; \\Delta \\vdash \\omega(P) \\approx L \\omega'(P) :: z : A[\\eta : \\omega \\leftrightarrow \\omega']$.\n\n**Soundness:** If $\\Omega; \\Gamma; \\Delta \\vdash P \\approx L Q :: z : A$ then $C[P] \\equiv C[Q] :: z : A$, for any closing $C [-]$.\n\n**Completeness:** If $\\Omega; \\Gamma; \\Delta \\vdash P \\equiv Q :: z : A$ then $\\Omega; \\Gamma; \\Delta \\vdash P \\approx L Q :: z : A$.\n\n### 3 To Linear-F and Back\n\nWe now develop our mutually inverse and fully abstract encodings between Polyπ and a linear polymorphic λ-calculus [55] that we dub Linear-F. We first introduce the syntax and typing of the linear λ-calculus and then proceed to detail our encodings and their properties (we omit typing ascriptions from the existential polymorphism constructs for readability).\n**Definition 3.1 (Linear-F).** The syntax of terms $M, N$ and types $A, B$ of Linear-F is given below.\n\n$$\nM, N ::= \\lambda x : A. M | MN | \\langle M \\otimes N \\rangle | \\text{let } x \\otimes y = M \\text{ in } N | ! M | \\text{let}!u = M \\text{ in } N | AX.M | M[A] | \\text{pack } A \\text{ with } M | \\text{let } (X,y) = M \\text{ in } N | 1 = M \\text{ in } N | \\langle \\rangle | T | F\n$$\n\n$$\nA, B ::= A \\rightarrow B | A \\otimes B | ! A \\forall X.A | \\exists X.A | X | 1 | 2\n$$\n\nThe syntax of types is that of the multiplicative and exponential fragments of second-order intuitionistic linear logic: $\\lambda x : A.M$ denotes linear $\\lambda$-abstractions; $MN$ denotes the application; $\\langle M \\otimes N \\rangle$ denotes the multiplicative pairing of $M$ and $N$, as reflected in its elimination form $\\text{let } x \\otimes y = M \\text{ in } N$ which simultaneously deconstructs the pair $M$, binding its first and second projection to $x$ and $y$ in $N$, respectively; $! M$ denotes a term $M$ that does not use any linear variables and so may be used an arbitrary number of times; $\\text{let}!u = M \\text{ in } N$ binds the underlying exponential term of $M$ as $u$ in $N$; $AX.M$ is the type abstraction former; $M[A]$ stands for type application; $\\text{pack } A \\text{ with } M$ is the existential type introduction form, where $M$ is a term where the existentially typed variable is instantiated with $A$; $\\text{let } (X,y) = M \\text{ in } N$ unpacks an existential package $M$, binding the representation type to $X$ and the underlying term to $y$ in $N$; the multiplicative unit $1$ has as introduction form the nullary pair $\\langle \\rangle$ and is eliminated by the construct $\\text{let } 1 = M \\text{ in } N$, where $M$ is a term of type $1$. Booleans (type $2$ with values $T$ and $F$) are the basic observable.\n\nThe typing judgment in Linear-F is given as $\\Omega; \\Gamma; \\Delta \\vdash M : A$, following the DILL formulation of linear logic \\cite{oneill2009}, stating that term $M$ has type $A$ in a linear context $\\Delta$ (i.e. bindings for linear variables $x:B$), intuitionistic context $\\Gamma$ (i.e. binding for intuitionistic variables $u:B$) and type variable context $\\Omega$. The typing rules are standard \\cite{girard1992}. The operational semantics of the calculus are the expected call-by-name semantics with commuting conversions \\cite{mendler1991}. We write $\\Downarrow$ for the evaluation relation. We write $\\cong$ for the largest typed congruence that is consistent with the observables of type $2$ (i.e. a so-called Morris-style equivalence as in \\cite{morris1990}).\n\n### 3.1 Encoding Linear-F into Session $\\pi$-Calculus\n\nWe define a translation from Linear-F to Poly$\\pi$ generalising the one from \\cite{tymbir2015}, accounting for polymorphism and multiplicative pairs. We translate typing derivations of $\\lambda$-terms to those of $\\pi$-calculus terms (we omit the full typing derivation for the sake of readability).\n\nProof theoretically, the $\\lambda$-calculus corresponds to a proof term assignment for natural deduction presentations of logic, whereas the session $\\pi$-calculus from \\cite{girard1992} corresponds to a proof term assignment for sequent calculus. Thus, we obtain a translation from $\\lambda$-calculus to the session $\\pi$-calculus by considering the proof theoretic content of the constructive proof of soundness of the sequent calculus wrt natural deduction. Following Gentzen \\cite{girard1992}, the translation from natural deduction to sequent calculus maps introduction rules to the corresponding right\nrules and elimination rules to a combination of the corresponding left rule, cut and/or identity.\n\nSince typing in the session calculus identifies a distinguished channel along which a process offers a session, the translation of \\( \\lambda \\)-terms is parameterised by a “result” channel along which the behaviour of the \\( \\lambda \\)-term is implemented. Given a \\( \\lambda \\)-term \\( M \\), the process \\( \\llbracket M \\rrbracket_z \\) encodes the behaviour of \\( M \\) along the session channel \\( z \\). We enforce that the type \\( 2 \\) of booleans and its two constructors are consistently translated to their polymorphic Church encodings before applying the translation to Poly\\( \\pi \\). Thus, type \\( 2 \\) is first translated to \\( \\forall X. ! X \\rightarrow ! X \\rightarrow X \\), the value \\( T \\) to \\( X. \\lambda u : X. \\lambda v : X. \\text{let} ! x = u \\text{in} \\text{let} ! y = v \\text{in} x \\) and the value \\( \\mathcal{F} \\) to \\( X. \\lambda u : X. \\lambda v : X. \\text{let} ! x = u \\text{in} \\text{let} ! y = v \\text{in} y \\). Such representations of the booleans are adequate up to parametricity [6] and suitable for our purposes of relating the session calculus (which has no primitive notion of value or result type) with the \\( \\lambda \\)-calculus precisely due to the tight correspondence between the two calculi.\n\nDefinition 3.2 (From Linear-F to Poly\\( \\pi \\)). \\( \\llbracket \\Omega \\rrbracket : \\llbracket \\Gamma \\rrbracket : \\llbracket \\Delta \\rrbracket \\vdash \\llbracket M \\rrbracket_z :: z : A \\) denotes the translation of contexts, types and terms from Linear-F to the polymorphic session calculus. The translations on contexts and types are the identity function. Booleans and their values are first translated to their Church encodings as specified above. The translation on \\( \\lambda \\)-terms is given below:\n\n\\[\n\\begin{align*}\n[x]_z & \\triangleq [x \\leftrightarrow z] & [MN]_z & \\triangleq (\\nu x)([M]_z \\| (\\nu y)x(y).([N]_y \\| [x \\leftrightarrow z])) \\\\\n[u]_z & \\triangleq (\\nu x)u(x).[x \\leftrightarrow z] & \\text{let} ! u = M \\text{in} N_z & \\triangleq (\\nu x)([M]_z \\| [N]_y \\| \\{x/u\\}) \\\\\n[\\lambda x : A. M]_z & \\triangleq \\nu x.([M]_z) & ![\\nu x.([M]_z)]_z & \\triangleq \\nu y.([M]_y \\| y(x).[N]_y) \\\\\n[M]_z & \\triangleq \\nu x.([M]_z) & \\text{let} x \\otimes y = M \\text{in} N_z & \\triangleq \\nu x([M]_y \\| x(A).[N]_y) \\\\\n[AX. M]_z & \\triangleq \\nu x.([M]_z) & \\text{let} (X, y) = M \\text{in} N_z & \\triangleq \\nu x([M]_y \\| x(A).[N]_y) \\\\\n[\\text{pack } A \\text{ with } M]_z & \\triangleq \\nu x.([M]_z) & \\text{let } 1 = M \\text{ in } N_z & \\triangleq \\nu x([M]_y \\| 1 \\otimes A).[N]_y) \\\\\n[\\langle \\rangle]_z & \\triangleq 0\n\\end{align*}\n\\]\n\nTo translate a (linear) \\( \\lambda \\)-abstraction \\( \\lambda x : A. M \\), which corresponds to the proof term for the introduction rule for \\( \\rightarrow \\), we map it to the corresponding \\( \\rightarrow R \\) rule, thus obtaining a process \\( \\nu x.([M]_z) \\) that inputs along the result channel \\( z \\) a channel \\( x \\) which will be used in \\( [M]_z \\) to access the function argument. To encode the application \\( MN \\), we compose (i.e. cut) \\([M]_z\\), where \\( x \\) is a fresh name, with a process that provides the (encoded) function argument by outputting along \\( x \\) a channel \\( y \\) which offers the behaviour of \\([N]_y\\). After the output is performed, the type of \\( x \\) is now that of the function’s codomain and we thus conclude by forwarding (i.e. the \\( \\text{id} \\) rule) between \\( x \\) and the result channel \\( z \\).\n\nThe encoding for polymorphism follows a similar pattern: To encode the abstraction \\( AX. M \\), we receive along the result channel a type that is bound to \\( X \\) and proceed inductively. To encode type application \\( M[A] \\) we encode the abstraction \\( M \\) in parallel with a process that sends \\( A \\) to it, and forwards accordingly. Finally, the encoding of the existential package \\( \\text{pack } A \\text{ with } M \\) maps to an output of the type \\( A \\) followed by the behaviour \\([M]_z\\), with the encoding of the elimination form \\( \\text{let } (X, y) = M \\text{ in } N \\) composing the translation of the term of existential type \\( M \\) with a process performing the appropriate type input and proceeding as \\([N]_z\\).\nExample 3.3 (Encoding of Linear-F). Consider the following λ-term corresponding to a polymorphic pairing function (recall that we write $\\bar{z}(w).P$ for $(uv)z(w).P$):\n\n$$M \\triangleq \\Lambda X.\\Lambda Y.\\Lambda x : X.\\Lambda y : Y.(x \\otimes y)$$\n\nand\n\n$$N \\triangleq ((M[A[B[M_1]M_2]])M_2)$$\n\nThen we have, with $\\bar{x} = x_1 x_2 x_3 x_4$:\n\n$$[N]_{\\bar{x}} \\equiv (\\nu \\bar{x})([M]_{x_1} \\mid x_1(A) \\mid x_2(B) \\mid x_3 \\leftrightarrow x_4) |\n\\bar{\\tau}(\\bar{x}) \\cdot ([M_1]_{x_1} \\mid [x_3 \\leftrightarrow x_4]) |\n\\bar{\\tau}(\\bar{y}) \\cdot ([M_2]_{y} \\mid [x_4 \\leftrightarrow z])$$\n\nWe can observe that $N \\rightarrow^+(((\\lambda x : A.\\lambda y : B.(x \\otimes y))M_1)M_2) \\rightarrow^+ (M_1 \\otimes M_2)$. At the process level, each reduction corresponding to the redex of type application is simulated by two reductions, obtaining:\n\n$$[N]_{\\bar{x}} \\rightarrow^+(\\nu x_3, x_4)(x_3(x), x_3(x), \\bar{\\tau}(\\bar{w}) \\cdot ([x \\leftrightarrow w] \\mid [y \\leftrightarrow x_3]) |\n\\bar{\\tau}(\\bar{x}) \\cdot ([M_1]_{x_3} \\mid [x_3 \\leftrightarrow x_4]) |\n\\bar{\\tau}(\\bar{y}) \\cdot ([M_2]_{y} \\mid [x_4 \\leftrightarrow z]) = P$$\n\nThe reductions corresponding to the β-redexes clarify the way in which the encoding represents substitution of terms for variables via fine-grained name passing. Consider $\\bar{\\tau}(\\bar{w}) \\cdot ([M_1]_{w} \\mid [M_2]_{z})$ and\n\n$$P \\rightarrow^+(\\nu x, y)([M_1]_{x} \\mid [M_2]_{y} \\mid \\bar{\\tau}(\\bar{w}) \\cdot ([x \\leftrightarrow w] \\mid [y \\leftrightarrow z]))$$\n\nThe encoding of the pairing of $M_1$ and $M_2$ outputs a fresh name $w$ which will denote the behaviour of (the encoding of) $M_1$, and then the behaviour of the encoding of $M_2$ is offered on $z$. The reduc of $P$ outputs a fresh name $w$ which is then identified with $x$ and thus denotes the behaviour of $[M_1]_{w}$. The channel $z$ is identified with $y$ and thus denotes the behaviour of $[M_2]_{z}$, making the two processes listed above equivalent. This informal reasoning exposes the insights that justify the operational correspondence of the encoding. Proof-theoretically, these equivalences simply map to commuting conversions which push the processes $[M_1]_{x}$ and $[M_2]_{z}$ under the output on $z$.\n\nTheorem 3.4 (Operational Correspondence).\n\n- If $\\Gamma; \\Delta \\vdash M : A$ and $M \\rightarrow N$ then $[M]_{\\bar{z}} \\Rightarrow P$ such that $[N]_{\\bar{z}} \\equiv_L P$\n- If $[M]_{\\bar{z}} \\rightarrow P$ then $M \\rightarrow^+ N$ and $[N]_{\\bar{z}} \\equiv_L P$\n\n3.2 Encoding Session π-calculus to Linear-F\n\nJust as the proof theoretic content of the soundness of sequent calculus wrt natural deduction induces a translation from λ-terms to session-typed processes, the completeness of the sequent calculus wrt natural deduction induces a translation from the session calculus to the λ-calculus. This mapping identifies sequent calculus right rules with the introduction rules of natural deduction and left rules with elimination rules combined with (type-preserving) substitution. Crucially, the mapping is defined on typing derivations, enabling us to consistently identify when a process uses a session (i.e. left rules) or, dually, when a process offers a session (i.e. right rules).\n\\begin{align*}\n\\frac{\\Delta, x:A \\vdash P : z:B}{\\Delta \\vdash z(x).P : z:A \\rightarrow B} & \\triangleq \\frac{\\Delta, x:A \\vdash \\langle P \\rangle_{\\Delta,x:A\\rightarrow z:B} : B}{\\Delta \\vdash \\lambda x:A.\\langle P \\rangle_{\\Delta,x:A\\rightarrow z:B} : A \\rightarrow B} \\\\\n\\frac{\\Delta_1 \\vdash P : y:A \\quad \\Delta_2, x:B \\vdash Q : z:C}{\\Delta_1, \\Delta_2, x:A \\rightarrow B \\vdash (\\nu y)x.(P \\mid Q) : z:C} & \\triangleq \\\\\n\\text{(subst)}\n\\frac{\\Delta_2, x:B \\vdash \\langle Q \\rangle_{\\Delta_2,x:B\\rightarrow z:C} : C}{\\frac{x:A \\rightarrow B \\vdash x:A \\rightarrow B \\quad \\Delta_1 \\vdash \\langle P \\rangle_{\\Delta_1,y:A} : B}{\\Delta_1, \\Delta_2, x:A \\rightarrow B \\vdash \\langle Q \\rangle_{\\Delta_2,x:B\\rightarrow z:C}(\\langle x \\langle P \\rangle_{\\Delta_1,y:A} \\rangle/x) : C}}\n\\end{align*}\n\nFig. 3. Translation on Typing Derivations (Excerpt – See [52])\n\n**Definition 3.5 (From Polyπ to Linear-F).** We write \\( \\langle Q \\rangle ; (I) ; (\\Delta) \\vdash \\langle P \\rangle : A \\) for the translation from typing derivations in Poly\\( \\pi \\) to derivations in Linear-F. The translations on types and contexts are the identity function. The translation on processes is given below, where the leftmost column indicates the typing rule at the root of the derivation (see Fig. 3 for an excerpt of the translation on typing derivations, where we write \\( \\langle P \\rangle_{\\Omega;\\Gamma;\\Delta\\vdash z:A} \\) to denote the translation of \\( \\Omega;\\Gamma;\\Delta \\vdash P : z:A \\). We omit \\( \\Omega \\) and \\( \\Gamma \\) when unchanged).\n\n\\begin{align*}\n(\\text{1R}) \\quad & \\langle \\emptyset \\rangle \\quad \\triangleq \\langle \\rangle \\\\\n(\\text{id}) \\quad & \\langle [x \\leftrightarrow y] \\rangle \\quad \\triangleq x \\\\\n(\\text{1L}) \\quad & \\langle P \\rangle \\quad \\triangleq \\text{let } 1 = x \\text{ in } \\langle P \\rangle \\\\\n(\\text{1L}) \\quad & \\langle [z(x).P] \\rangle \\quad \\triangleq \\lambda x:A.\\langle P \\rangle \\\\\n(\\text{1L}) \\quad & \\langle [\\forall x . P] \\rangle \\quad \\triangleq \\text{let } u = x \\text{ in } \\langle P \\rangle \\\\\n(\\text{1L}) \\quad & \\forall X . \\langle P \\rangle \\\\\n(\\text{3L}) \\quad & \\langle [\\exists x . P] \\rangle \\quad \\triangleq \\text{let } (Y,x) = x \\text{ in } \\langle P \\rangle \\\\\n(\\text{cut}) \\quad & \\langle [\\exists x . (P \\mid Q)] \\rangle \\quad \\triangleq \\langle [Q] \\rangle \\langle [P]/x \\rangle \\\\\n(\\text{cut'}) \\quad & \\langle [\\forall u . (P \\mid Q)] \\rangle \\quad \\triangleq \\langle [Q] \\rangle \\langle [P]/u \\rangle\n\\end{align*}\n\nFor instance, the encoding of a process \\( z(x).P : z:A \\rightarrow B \\), typed by rule \\( \\rightarrow\\text{R} \\), results in the corresponding \\( \\rightarrow I \\) introduction rule in the \\( \\lambda \\)-calculus and thus is \\( \\lambda x:A.\\langle P \\rangle \\). To encode the process \\( (\\nu y)x.(P \\mid Q) \\), typed by rule \\( \\rightarrow\\text{L} \\), we make use of substitution: Given that the sub-process \\( Q \\) is typed as \\( \\Omega;\\Gamma;\\Delta',x:B \\vdash Q : z:C \\), the encoding of the full process is given by \\( \\langle Q \\rangle \\langle [x \\langle P \\rangle]/x \\rangle \\). The term \\( x \\langle P \\rangle \\) consists of the application of \\( x \\) (of function type) to the argument \\( \\langle P \\rangle \\), thus ensuring that the term resulting from the substitution is of the appropriate type. We note that, for instance, the encoding of rule \\( \\otimes\\text{L} \\) does not need to appeal to substitution – the \\( \\lambda \\)-calculus let style rules can be mapped directly. Similarly, rule \\( \\forall\\text{R} \\) is mapped to type abstraction, whereas rule \\( \\forall\\text{L} \\) which types a process of the form \\( x(B).P \\) maps to a substitution of the type application \\( x[B] \\) for \\( x \\) in \\( \\langle P \\rangle \\). The encoding of existential polymorphism is simpler due to the let-style elimination. We also highlight the encoding of the cut rule which\nembraces parallel composition of two processes sharing a linear name, which clarifies the use/offer duality of the intuitionistic calculus — the process that offers \\( P \\) is encoded and substituted into the encoded user \\( Q \\).\n\n**Theorem 3.6.** If \\( \\Omega; \\Gamma; \\Delta \\vdash P :: z: A \\) then \\( \\langle \\Omega \\rangle; \\langle \\Gamma \\rangle; \\langle \\Delta \\rangle \\vdash \\langle P \\rangle :: \\langle A \\rangle \\).\n\n**Example 3.7 (Encoding of PolyPi).** Consider the following processes\n\n\\[\nP \\triangleq z(X).z(Y).z(x).\\exists(w).\\{[x \\leftrightarrow w] \\mid [y \\leftrightarrow z]\\} \\quad Q \\triangleq z(1).z(1).\\exists(x).\\exists(y).z(w).[w \\leftrightarrow r]\n\\]\n\nwith \\( \\vdash P :: z: \\forall X. \\forall Y.X \\rightarrow Y \\rightarrow X \\otimes Y \\) and \\( z: \\forall X. \\forall Y.X \\rightarrow Y \\rightarrow X \\otimes Y \\vdash Q :: r: 1 \\).\n\nThen: \\( \\{P\\} = (X.\\forall Y.\\lambda x: X.\\exists w: Y.\\{x \\otimes y\\}) \\quad \\{Q\\} = \\text{let } x \\otimes y = z[1][1] \\{\\} \\text{ in let } 1 = y \\text{ in } x\\)\n\n\\[\n\\{((\\nu z)(P \\mid Q)) \\text{ in let } 1 = y \\text{ in } x\\}\n\\]\n\nBy the behaviour of \\((\\nu z)(P \\mid Q)\\), which consists of a sequence of cuts, and its encoding, we have that \\((\\nu z)(P \\mid Q) \\rightarrow^* \\{\\}\\) and \\((\\nu z)(P \\mid Q) \\rightarrow^* 0 = \\langle \\{\\} \\rangle\\).\n\nIn general, the translation of Def. 3.5 can introduce some distance between the immediate operational behaviour of a process and its corresponding \\( \\lambda \\)-term, insofar as the translations of cuts (and left rules to non let-form elimination rules) make use of substitutions that can take place deep within the resulting term. Consider the process at the root of the following typing judgment \\( \\Delta_1, \\Delta_2, \\Delta_3 \\vdash (\\nu x)(x(y).P_1 \\mid (\\nu y)x(y).(P_2 \\mid w(z).0)) :: w: 1 \\rightarrow 1 \\), derivable through a cut on session \\( x \\) between instances of \\( \\rightarrow R \\) and \\( \\rightarrow L \\), where the continuation process \\( w(z).0 \\) offers a session \\( w: 1 \\rightarrow 1 \\) (and so must use rule 1L on \\( x \\)). We have that: \\((\\nu x)(x(y).P_1 \\mid (\\nu y)x(y).(P_2 \\mid w(z).0)) \\rightarrow (\\nu x,y)(P_1 \\mid P_2 \\mid w(z).0)\\). However, the translation of the process above results in the term \\( \\lambda z: 1.\\text{let } 1 = ((\\lambda y: A.(P_1)) \\langle P_2 \\rangle) \\text{ in let } 1 = z \\text{ in } \\langle \\rangle\\), where the redex that corresponds to the process reduction is present but hidden under the binder for \\( z \\) (corresponding to the input along \\( w \\)). Thus, to establish operational completeness we consider full \\( \\beta \\)-reduction, denoted by \\( \\rightarrow_\\beta \\), i.e. enabling \\( \\beta \\)-reductions under binders.\n\n**Theorem 3.8 (Operational Completeness).** Let \\( \\Omega; \\Gamma; \\Delta \\vdash P :: z: A \\). If \\( P \\rightarrow Q \\) then \\( \\langle P \\rangle \\rightarrow_\\beta^* \\langle Q \\rangle \\).\n\nIn order to study the soundness direction it is instructive to consider typed process \\( x: 1 \\rightarrow 1 \\vdash \\pi(y), (\\nu z)(z(w).0 \\mid \\pi(w).0) :: v: 1 \\) and its translation:\n\n\\[\n\\langle \\pi(y).((\\nu z)(z(w).0 \\mid \\pi(w).0)) \\rangle = \\langle ((\\nu z)(z(w).0 \\mid \\pi(w).0)) \\{x\\} \\rangle \\{x\\}\n\\]\n\nThe process above cannot reduce due to the output prefix on \\( x \\), which cannot synchronise with a corresponding input action since there is no provider for \\( x \\) (i.e. the channel is in the left-hand side context). However, its encoding can exhibit the \\( \\beta \\)-redex corresponding to the synchronisation along \\( z \\), hidden by the prefix on \\( x \\). The corresponding reductions hidden under prefixes in the encoding can be soundly exposed in the session calculus by appealing to the commuting conversions of linear logic (e.g. in the process above, the instance of rule \\( \\rightarrow L \\) corresponding to the output on \\( x \\) can be commuted with the cut on \\( z \\).)\nAs shown in [30], commuting conversions are sound wrt observational equivalence, and thus we formulate operational soundness through a notion of extended process reduction, which extends process reduction with the reductions that are induced by commuting conversions. Such a relation was also used for similar purposes in [5] and in [26], in a classical linear logic setting. For conciseness, we define extended reduction as a relation on typed processes modulo $\\equiv$.\n\n**Definition 3.9 (Extended Reduction [5]).** We define $\\mapsto$ as the type preserving relations on typed processes modulo $\\equiv$ generated by:\n\n1. $C[(\\nu y)x(y).P] \\mid x(y).Q \\mapsto C[(\\nu y)(P \\mid Q)]$;\n2. $C[(\\nu y)x(y).P] \\mid [x(y).Q \\mapsto C[(\\nu y)(P \\mid Q)] \\mid x(y).Q$; and (3) $(\\nu x)([x(y).Q) \\mapsto 0$\n\nwhere $C$ is a (typed) process context which does not capture the bound name $y$.\n\n**Theorem 3.10 (Operational Soundness).** Let $\\Omega; \\Gamma; \\Delta \\vdash P :: z:A$ and $[P] \\rightarrow M$, there exists $Q$ such that $P \\rightarrow^* Q$ and $[Q] =_{\\alpha} M$.\n\n### 3.3 Inversion and Full Abstraction\n\nHaving established the operational preciseness of the encodings to-and-from Poly$\\pi$ and Linear-F, we establish our main results for the encodings. Specifically, we show that the encodings are mutually inverse up-to behavioural equivalence (with fullness as its corollary), which then enables us to establish full abstraction for both encodings.\n\n**Theorem 3.11 (Inverse).** If $\\Omega; \\Gamma; \\Delta \\vdash M : A$ then $\\Omega; \\Gamma; \\Delta \\vdash [\\langle M \\rangle_z] \\cong M : A$. Also, if $\\Omega; \\Gamma; \\Delta \\vdash P :: z:A$ then $\\Omega; \\Gamma; \\Delta \\vdash [\\langle P \\rangle_z] \\approx_{\\alpha} P :: z:A$\n\n**Corollary 3.12 (Fullness).** Let $\\Omega; \\Gamma; \\Delta \\vdash P :: z:A. \\exists M \\ s.t. \\ \\Omega; \\Gamma; \\Delta \\vdash M : A$ and $\\Omega; \\Gamma; \\Delta \\vdash [\\langle M \\rangle_z] \\approx_{\\alpha} P :: z:A$ Also, let $\\Omega; \\Gamma; \\Delta \\vdash M : A. \\exists P \\ s.t. \\ \\Omega; \\Gamma; \\Delta \\vdash P :: z:A$ and $\\Omega; \\Gamma; \\Delta \\vdash [\\langle P \\rangle_z] \\cong M : A$.\n\nWe now state our full abstraction results. Given two Linear-F terms of the same type, equivalence in the image of the $[\\langle \\cdot \\rangle_z]$ translation can be used as a proof technique for contextual equivalence in Linear-F. This is called the soundness direction of full abstraction in the literature [18] and proved by showing the relation generated by $[\\langle M \\rangle_z] \\approx_{\\alpha} [\\langle N \\rangle_z]$ forms $\\cong$; we then establish the completeness direction by contradiction, using fullness.\n\n**Theorem 3.13 (Full Abstraction).** $\\Omega; \\Gamma; \\Delta \\vdash M \\cong N : A$ iff $\\Omega; \\Gamma; \\Delta \\vdash [\\langle M \\rangle_z] \\approx_{\\alpha} [\\langle N \\rangle_z] :: z:A$.\n\nWe can straightforwardly combine the above full abstraction with Theorem 3.11 to obtain full abstraction of the $[\\langle \\cdot \\rangle]$ translation.\n\n**Theorem 3.14 (Full Abstraction).** $\\Omega; \\Gamma; \\Delta \\vdash P \\cong_{\\alpha} Q :: z:A$ iff $\\Omega; \\Gamma; \\Delta \\vdash [\\langle P \\rangle] \\cong [\\langle Q \\rangle] : A$. \n4 Applications of the Encodings\n\nIn this section we develop applications of the encodings of the previous sections. Taking advantage of full abstraction and mutual inversion, we apply non-trivial properties from the theory of the $\\lambda$-calculus to our session-typed process setting.\n\nIn §4.1 we study inductive and coinductive sessions, arising through encodings of initial $F$-algebras and final $F$-coalgebras in the polymorphic $\\lambda$-calculus.\n\nIn §4.2 we study encodings for an extension of the core session calculus with term passing, where terms are derived from a simply-typed $\\lambda$-calculus. Using the development of §4.2 as a stepping stone, we generalise the encodings to a higher-order session calculus (§4.3), where processes can send, receive and execute other processes. We show full abstraction and mutual inversion theorems for the encodings from higher-order to first-order. As a consequence, we can straightforwardly derive a strong normalisation property for the higher-order process-passing calculus.\n\n4.1 Inductive and Coinductive Session Types\n\nThe study of polymorphism in the $\\lambda$-calculus [1,19,40,6] has shown that parametric polymorphism is expressive enough to encode both inductive and coinductive types in a precise way, through a faithful representation of initial and final (co)algebras [28], without extending the language of terms nor the semantics of the calculus, giving a logical justification to the Church encodings of inductive datatypes such as lists and natural numbers. The polymorphic session calculus can express fairly intricate communication behaviours, including generic protocols through both existential and universal polymorphism (i.e. protocols that are parametric in their sub-protocols). Using our fully abstract encodings between the two calculi, we show that session polymorphism is expressive enough to encode inductive and coinductive sessions, “importing” the results for the $\\lambda$-calculus, which may then be instantiated to provide a session-typed formulation of the encodings of data structures in the $\\pi$-calculus of [50].\n\n**Inductive and Coinductive Types in System F.** Exploring an algebraic interpretation of polymorphism where types are interpreted as functors, it can be shown that given a type $F$ with a free variable $X$ that occurs only positively (i.e. occurrences of $X$ are on the left-hand side of an even number of function arrows), the polymorphic type $\\forall X.((F(X) \\to X) \\to X)$ forms an initial $F$-algebra [42] (we write $F(X)$ to denote that $X$ occurs in $F$). This enables the representation of *inductively* defined structures using an algebraic or categorical justification. For instance, the natural numbers can be seen as the initial $F$-algebra of $F(X) = 1 + X$ (where 1 is the unit type and $+$ is the coproduct), and are thus *already present* in System F, in a precise sense, as the type $\\forall X.((1 + X) \\to X) \\to X$ (noting that both 1 and $+$ can also be encoded in System F). A similar story can be told for *coinductively* defined structures, which correspond to final $F$-coalgebras and are representable with the polymorphic type $\\exists X.(X \\to F(X)) \\times X$, where $\\times$ is a product type. In the remainder of this section we assume the positivity requirement on $F$ mentioned above.\nWhile the complete formal development of the representation of inductive and coinductive types in System F would lead us to far astray, we summarise here the key concepts as they apply to the λ-calculus (the interested reader can refer to [19] for the full categorical details).\n\nTo show that the polymorphic type \\( T_i \\triangleq \\forall X.((F(X) \\to X) \\to X) \\) is an initial \\( F \\)-algebra, one exhibits a pair of \\( \\lambda \\)-terms, often dubbed fold and in, such that the diagram in Fig. 4(a) commutes (for any \\( A \\), where \\( F(f) \\), where \\( f \\) is a \\( \\lambda \\)-term, denotes the functorial action of \\( F \\) applied to \\( f \\)), and, crucially, that fold is unique. When these conditions hold, we are justified in saying that \\( T_i \\) is a least fixed point of \\( F \\). Through a fairly simple calculation, it is easy to see that:\n\n\\[\n\\text{fold} \\triangleq \\lambda X.\\lambda x:F(X) \\to X.\\lambda t:T_i.t[X](x)\n\\]\n\n\\[\n\\text{in} \\triangleq \\lambda x:F(T_i).\\lambda X.\\lambda y:F(X) \\to X.y(F(\\text{fold}[X](x))(x))\n\\]\n\nsatisfy the necessary equalities. To show uniqueness one appeals to parametricity, which allows us to prove that any function of the appropriate type is equivalent to fold. This property is often dubbed initiality or universality.\n\nThe construction of final \\( F \\)-coalgebras and their justification as greatest fixed points is dual. Assuming products in the calculus and taking \\( T_f \\triangleq \\exists X.(X \\to F(X)) \\times X \\), we produce the \\( \\lambda \\)-terms\n\n\\[\n\\text{unfold} \\triangleq \\lambda X.\\lambda f:X \\to F(X).\\lambda x:T_f.\\text{pack}(f,x)\n\\]\n\n\\[\n\\text{out} \\triangleq \\lambda t:T_f.\\text{let}(X,(f,x)) = t \\text{ in } F(\\text{unfold}[X](f)(f(x)))\n\\]\n\nsuch that the diagram in Fig. 4(b) commutes and unfold is unique (again, up to parametricity). While the argument above applies to System F, a similar development can be made in Linear-F [6] by considering \\( T_i \\triangleq \\forall X.!(F(X) \\to X) \\to X \\) and \\( T_f \\triangleq \\exists X.!(X \\to F(X)) \\to X \\). Reusing the same names for the sake of conciseness, the associated linear \\( \\lambda \\)-terms are:\n\n\\[\n\\text{fold} \\triangleq \\lambda X.\\lambda u:!(F(X) \\to X).\\lambda y:T_i.(y[X]u) : \\forall X.!(F(X) \\to X) \\to T_i \\to X\n\\]\n\n\\[\n\\text{in} \\triangleq \\lambda x:F(T_i).\\lambda X.\\lambda y:!(F(X) \\to X).\\text{let}!u = y \\text{ in } k(F(\\text{fold}[X!(t)])(x)) : F(T_i) \\to T_i\n\\]\n\n\\[\n\\text{unfold} \\triangleq \\lambda X.\\lambda u:!(X \\to F(X)).\\lambda x:X.\\text{pack}X \\text{ with } (u \\otimes x) : \\forall X.!(X \\to F(X)) \\to X \\to T_f\n\\]\n\n\\[\n\\text{out} \\triangleq \\lambda t:T_f.\\text{let}(X,(u,x)) = t \\text{ in } !f = u \\text{ in } F(\\text{unfold}[X!(t)](f)(f(x))) : T_f \\to F(T_f)\n\\]\n\n**Inductive and Coinductive Sessions for Free.** As a consequence of full abstraction we may appeal to the \\([[-]]\\) encoding to derive representations of fold\nas an inductive session type using Example 4.3 (Natural Numbers).\n\nWe show how to represent the natural numbers as due to the generic nature of the encodings arise due to our primitive notions of labels and forwarding, as well as foldP\n\n\\[\n\\text{foldP}(A)_y \\triangleq (\\nu x)(\\text{foldP}_x \\mid x(A), \\mathbf{π}(v), [y \\leftrightarrow v] \\mid \\mathbf{π}(z), ([z \\leftrightarrow y_1] \\mid [x \\leftrightarrow y_2]))\n\\]\n\n\\[\n\\text{unfoldP}(A)_y \\triangleq (\\nu x)(\\text{unfoldP}_x \\mid x(A), \\mathbf{π}(v), [y \\leftrightarrow v] \\mid \\mathbf{π}(z), ([z \\leftrightarrow y_1] \\mid [x \\leftrightarrow y_2]))\n\\]\n\nwhere \\(\\text{foldP}(A)_{y_1,y_2}\\) corresponds to the application of fold to an \\(F\\)-algebra \\(A\\) with the associated morphism \\(F(A) \\rightarrow A\\) available on the shared channel \\(u\\), consuming an ambient session \\(y_1:T_1\\) and offering \\(y_2:A\\). Similarly, \\(\\text{unfoldP}(A)_{y_1,y_2}\\) corresponds to the application of unfold to an \\(F\\)-coalgebra \\(A\\) with the associated morphism \\(A \\rightarrow F(A)\\) available on the shared channel \\(u\\), consuming an ambient session \\(y_1:A\\) and offering \\(y_2:T_f\\).\n\n**Theorem 4.1 (Universality of foldP).** \\(\\forall Q\\) such that \\(X; u:F(X) \\rightarrow X; y_1:T_1 \\vdash Q :: y_2:X\\) we have \\(X; u:F(X) \\rightarrow X; y_1:T_1 \\vdash Q \\approx \\text{foldP}(X)_{y_1,y_2} :: y_2:X\\)\n\n**Theorem 4.2 (Universality of unfoldP).** \\(\\forall Q\\) and \\(F\\)-coalgebra \\(A\\) s.t. \\(\\vdash y_1:A \\vdash Q :: y_2:T_f\\) we have that \\(\\vdash u:F(A) \\rightarrow A; y_1:A \\vdash Q \\approx \\text{unfoldP}(A)_{y_1,y_2} :: y_2 :: T_f\\).\n\n**Example 4.3 (Natural Numbers).** We show how to represent the natural numbers as an inductive session type using \\(F(X) = 1 \\oplus X\\), making use of in:\n\n\\[\n\\text{zero}_x \\triangleq (\\nu z)(z.\\mathbf{in}; 0 \\mid [\\mathbf{in}(z)]_x) \\quad \\text{succ}_{y,x} \\triangleq (\\nu s)(s.\\mathbf{inr}; [y \\leftrightarrow s] \\mid [\\mathbf{in}(s)]_x)\n\\]\n\nwith \\(\\text{Nat} \\triangleq \\forall X!((1 \\oplus X) \\rightarrow X) \\rightarrow X\\) where \\(\\vdash \\text{zero}_x :: x:\\text{Nat}\\) and \\(y:\\text{Nat} \\vdash \\text{succ}_{y,x} :: x:\\text{Nat}\\) encode the representation of 0 and successor, respectively. The natural 1 would thus be represented by \\(\\text{one}_x \\triangleq (\\nu y)(\\text{zero}_y \\mid \\text{succ}_{y,x})\\). The behaviour of type \\(\\text{Nat}\\) can be seen as a that of a sequence of internal choices of arbitrary (but finite) length. We can then observe that the foldP process acts as a recursive. For instance consider:\n\n\\[\n\\text{stepDec}_d \\triangleq d(n).n.\\text{case}(\\text{zero}_x, [n \\leftrightarrow d]) \\quad \\text{dec}_{x,z} \\triangleq (\\nu u)(!u(d).\\text{stepDec}_d \\mid \\text{foldP}(\\text{Nat})_{x,z})\n\\]\n\nwith \\(\\text{stepDec}_d :: d:(1 \\oplus \\text{Nat}) \\rightarrow \\text{Nat}\\) and \\(x:\\text{Nat} \\vdash \\text{dec}_{x,z} :: z:\\text{Nat}\\), where \\(\\text{dec}\\) decrements a given natural number session on channel \\(x\\). We have that:\n\n\\[\n(\\nu x)(\\text{one}_x \\mid \\text{dec}_{x,z}) \\equiv (\\nu x,y,u)(\\text{zero}_y \\mid \\text{succ}_{y,x}!u(d).\\text{stepDec}_d \\mid \\text{foldP}(\\text{Nat})_{x,z}) \\approx L \\text{ zero}_x\n\\]\n\nWe note that the resulting encoding is reminiscent of the encoding of lists of \\([30]\\) (where \\(\\text{zero}\\) is the empty list and \\(\\text{succ}\\) the cons cell). The main differences in the encodings arise due to our primitive notions of labels and forwarding, as well as due to the generic nature of in and fold.\nExample 4.4 (Streams). We build on Example 4.3 by representing streams of natural numbers as a coinductive session type. We encode infinite streams of naturals with \\( F(X) = \\text{Nat} \\otimes X \\). Thus: \\( \\text{NatStream} \\triangleq \\exists X.(! (\\text{Nat} \\otimes X)) \\otimes X \\).\n\nThe behaviour of a session of type \\( \\text{NatStream} \\) amounts to an infinite sequence of outputs of channels of type \\( \\text{Nat} \\). Such an encoding enables us to construct the stream of all naturals \\( \\text{nats} \\) (and the stream of all non-zero naturals \\( \\text{oneNats} \\)):\n\n\\[\n\\begin{align*}\ngenHdNext_x & \\triangleq z(n).\\exists y.(\\pi(n').[n' \\leftrightarrow y] \\mid !z(w).\\pi(n').\\text{succ}_{n',w}) \\\\\n\\text{nats}_y & \\triangleq (\\nu x,u)(\\text{zero}_x \\mid !u(z).\\text{genHdNext}_x \\mid \\text{unfoldP}(!\\text{Nat})_{x,y}) \\\\\n\\text{oneNats}_y & \\triangleq (\\nu x,u)(\\text{one}_x \\mid !u(z).\\text{genHdNext}_x \\mid \\text{unfoldP}(!\\text{Nat})_{x,y})\n\\end{align*}\n\\]\n\nwith \\( \\text{genHdNext}_x :: z!\\text{Nat} \\rightarrow \\text{Nat} \\otimes !\\text{Nat} \\) and both \\( \\text{nats}_y \\) and \\( \\text{oneNats} :: y:\\text{NatStream} \\).\n\n\\( \\text{genHdNext}_x \\) consists of a helper that generates the current head of a stream and the next element. As expected, the following process implements a session that “unrolls” the stream once, providing the head of the stream and then behaving as the rest of the stream (recall that \\( \\text{out} : T_f \\rightarrow F(T_f) \\)).\n\n\\[\n(\\nu x)(\\text{nats}_x \\mid \\llbracket\\text{out}(x)\\rrbracket_y) :: y:\\text{Nat} \\otimes \\text{NatStream}\n\\]\n\nWe note a peculiarity of the interaction of linearity with the stream encoding: a process that begins to deconstruct a stream has no way of “bottoming out” and stopping. One cannot, for instance, extract the first element of a stream of naturals. As expected, the following process implements a session that stops unrolling the stream in a well-typed way. We can, however, easily encode a “terminating” stream of all natural numbers via \\( F(X) = (\\text{Nat} \\otimes !X) \\) by replacing the \\( \\text{genHdNext}_x \\) with the generator given as:\n\n\\[\n\\begin{align*}\ngenHdNextTer_x & \\triangleq z(n).\\exists y.(\\pi(n').[n' \\leftrightarrow y] \\mid !z(w)!w(w').\\pi(n').\\text{succ}_{n',w'})\n\\end{align*}\n\\]\n\nIt is then easy to see that a usage of \\( \\llbracket\\text{out}(x)\\rrbracket_y \\) results in a session of type \\( \\text{Nat} \\otimes !\\text{NatStream} \\), enabling us to discard the stream as needed. One can replay this argument with the operator \\( F(X) = (!\\text{Nat} \\otimes X) \\) to enable discarding of stream elements. Assuming such modifications, we can then show:\n\n\\[\n(\\nu y)((\\nu x)(\\text{nats}_x \\mid \\llbracket\\text{out}(x)\\rrbracket_y) \\mid y(n).[y \\leftrightarrow z]) \\approxL \\text{oneNats}_x :: z:\\text{NatStream}\n\\]\n\n4.2 Communicating Values – \\( \\text{Sess} \\pi \\lambda \\)\n\nWe now consider a session calculus extended with a data layer obtained from a \\( \\lambda \\)-calculus (whose terms are ranged over by \\( M,N \\) and types by \\( \\tau,\\sigma \\)). We dub this calculus \\( \\text{Sess} \\pi \\lambda \\).\n\n\\[\n\\begin{align*}\nP,Q ::= \\cdots \\mid x(M).P \\mid x(y).P & \\quad A,B ::= \\cdots \\mid \\tau \\land A \\mid \\tau \\lor A \\\\\nM,N ::= \\lambda x:\\tau.M \\mid M N \\mid x & \\quad \\tau,\\sigma ::= \\cdots \\mid \\tau \\rightarrow \\sigma\n\\end{align*}\n\\]\n\nWithout loss of generality, we consider the data layer to be simply-typed, with a call-by-name semantics, satisfying the usual type safety properties. The typing judgment for this calculus is \\( \\Psi \\vdash M : \\tau \\). We omit session polymorphism for the sake of conciseness, restricting processes to communication of data and (session) channels. The typing judgment for processes is thus modified to \\( \\Psi; \\Gamma; \\Delta \\vdash P :: \\)\nthe encoding of $\\tau$ according to $\\Psi$. Using a session of type $\\Gamma; \\Delta \\vdash \\tau$ we define the process semantics through a reduction rule at the root of the typing derivation.\n\n\\[\n\\frac{\\Psi, \\eta \\vdash M : \\tau}{\\Psi, \\eta, \\eta' \\vdash M : \\tau} \\quad (\\land R)\n\\]\n\n\\[\n\\frac{\\Psi, \\eta \\vdash \\tau ; \\eta' \\vdash P : z : A}{\\Psi, \\eta, \\eta' \\vdash \\tau ; \\eta' \\vdash P : z : A} \\quad (\\lor R)\n\\]\n\nThe encoding addresses the non-linear usage of data elements in processes by encoding types $\\tau$ and $\\eta$ as $\\Psi$ context that accounts for variables in the data layer. The rules for the relevant process constructs are (all other rules simply propagate the $\\Psi$ context from conclusion to premises):\n\n\\[\n\\frac{\\Psi, \\eta \\vdash M : \\tau; \\Psi, \\eta \\vdash \\eta' \\vdash z(M).P \\vdash z : \\tau \\land A}{\\Psi, \\eta, \\eta' \\vdash z(M).P \\vdash z : \\tau \\land A} \\quad (\\land L)\n\\]\n\n\\[\n\\frac{\\Psi, \\eta \\vdash \\tau \\land A \\vdash x(y).Q \\vdash z : C}{\\Psi, \\eta, \\eta' \\vdash \\tau \\land A \\vdash x(y).Q \\vdash z : C} \\quad (\\lor L)\n\\]\n\nFor simplicity, in this section, we define the process semantics through a reduction relation.\n\nWith the reduction rule given by\\(^1\\) $x(M).P \\mid x(y).Q \\rightarrow P \\mid Q[M/y]$. With a simple extension to our encodings we may eliminate the data layer by encoding the data objects as processes, showing that from an expressiveness point of view, data communication is orthogonal to the framework. We note that the data language we are considering is not linear, and the usage discipline of data in processes is itself also not linear.\n\nTo First-Order Processes We now introduce our encoding for Sess$\\pi\\lambda$, defined inductively on session types, processes, types and $\\lambda$-terms (we omit the purely inductive cases on session types and processes for conciseness). As before, the encoding on processes is defined on *typing derivations*, where we indicate the typing rule at the root of the typing derivation.\n\n\\[\n[\\tau \\land A] \\triangleq [\\tau] \\otimes [A] \\quad [\\tau \\lor A] \\triangleq [\\tau] \\rightarrow [A] \\quad [\\tau \\rightarrow \\sigma] \\triangleq [\\tau] \\rightarrow \\sigma\n\\]\n\n\\[\n(\\land R) \\quad [z(M).P] \\triangleq \\tau(x).([x(y).[M]_y] \\mid [P]) \\quad (\\land L) \\quad [x(y).P] \\triangleq \\tau(x).[P]\n\\]\n\n\\[\n(\\lor R) \\quad [z(x).P] \\triangleq \\tau(x).[P] \\quad (\\lor L) \\quad [\\tau(M).P] \\triangleq \\tau(y).([y(w).[M]_w] \\mid [P])\n\\]\n\n\\[\n[x]_x \\triangleq \\tau(y).[y \\leftrightarrow z] \\quad [\\lambda x : \\tau.\\!(M)]_x \\triangleq \\tau(x).[M]_x\n\\]\n\n\\[\n[M \\!N]_y \\triangleq (\\nu y)(([M]_y \\mid \\Psi(x).(M(w).[N]_w) \\mid [y \\leftrightarrow z]))\n\\]\n\nThe encoding addresses the non-linear usage of data elements in processes by encoding the types $\\tau \\land A$ and $\\tau \\lor A$ as $[\\tau] \\otimes [A]$ and $[\\tau] \\rightarrow [A]$, respectively. Thus, sending and receiving of data is codified as the sending and receiving of channels of type $!$, which therefore can be used non-linearly. Moreover, since data terms are themselves non-linear, the $\\tau \\rightarrow \\sigma$ type is encoded as $[\\tau] \\rightarrow [\\sigma]$, following Girard’s embedding of intuitionistic logic in linear logic\\(^3\\).\n\nAt the level of processes, offering a session of type $\\tau \\land A$ (i.e. a process of the form $z(M).P$) is encoded according to the translation of the type: we first send a fresh name $x$ which will be used to access the encoding of the term $M$. Since $M$ can be used an arbitrary number of times by the receiver, we guard the encoding of $M$ with a replicated input, proceeding with the encoding of $P$ accordingly. Using a session of type $\\tau \\lor A$ follows the same principle. The input cases (and the rest of the process constructs) are completely homomorphic.\n\nThe encoding of $\\lambda$-terms follows Girard’s decomposition of the intuitionistic function space\\(^4\\). The $\\lambda$-abstraction is translated as input. Since variables in a $\\lambda$-abstraction may be used non-linearly, the case for variables and application\n\n---\n\n\\(^1\\) For simplicity, in this section, we define the process semantics through a reduction relation.\nis slightly more intricate: to encode the application \\( MN \\) we compose \\( M \\) in parallel with a process that will send the “reference” to the function argument \\( N \\) which will be encoded using replication, in order to handle the potential for 0 or more usages of variables in a function body. Respectively, a variable is encoded by performing an output to trigger the replication and forwarding accordingly. Without loss of generality, we assume variable names and their corresponding replicated counterparts match, which can be achieved through \\( \\alpha \\)-conversion before applying the translation. We exemplify our encoding as follows:\n\n\\[\n\\begin{align*}\n[z(x).z(x).z((\\lambda y.\\sigma.x)).0] &= z(x).\\overline{z}(w).((w(u).[x]_w | \\overline{z}(v).((v(i).\\overline{[\\lambda y.\\sigma.x]}_i | 0))) \\\\\n&= z(x).\\overline{z}(w).((w(u).\\overline{x}(y).[y \\leftrightarrow w] | \\overline{z}(v).((v(i).\\overline{x}(t).[t \\leftrightarrow i] | 0))))\n\\end{align*}\n\\]\n\nProperties of the Encoding. We discuss the correctness of our encoding. We can straightforwardly establish that the encoding preserves typing.\n\nTo show that our encoding is operationally sound and complete, we capture the interaction between substitution on \\( \\lambda \\)-terms and the encoding into processes through logical equivalence. Consider the following reduction of a process:\n\n\\[\n(\\nu z)(z(x).z(x).z((\\lambda y.\\sigma.x)).0 | z((\\lambda w:\\tau_0.w).P))\n\\]\n\n\\[\n\\rightarrow (\\nu z)(z(\\lambda w:\\tau_0.w).z((\\lambda y.\\sigma.\\lambda w:\\tau_0.w)).0 | P) \\quad (1)\n\\]\n\nGiven that substitution in the target session \\( \\pi \\)-calculus amounts to renaming, whereas in the \\( \\lambda \\)-calculus we replace a variable for a term, the relationship between the encoding of a substitution \\( M\\{N/x\\} \\) and the encodings of \\( M \\) and \\( N \\) corresponds to the composition of the encoding of \\( M \\) with that of \\( N \\), but where the encoding of \\( N \\) is guarded by a replication, codifying a form of explicit non-linear substitution.\n\nLemma 4.5 (Compositionality). Let \\( \\Psi, x: \\tau \\vdash M : \\sigma \\) and \\( \\Psi \\vdash N : \\tau \\). We have that \\( [[M\\{N/x\\}]_x \\approx_L (\\nu x)([[M]]_x | [x(y)].[[N]]_y)\\)\n\nRevisiting the process to the left of the arrow in Equation[1] we have:\n\n\\[\n[[\\nu z](z(x).z(x).z((\\lambda y.\\sigma.x)).0 | z((\\lambda w:\\tau_0.w).P))] \\\\\n= (\\nu z)[[[z(x).z(x).z((\\lambda y.\\sigma.x)).0]_x | \\overline{z}(x).((x(b).[[\\lambda w:\\tau_0.w]]_b | [P])]) \\\\\n\\rightarrow (\\nu z)(z(x)).\\overline{z}(w).((w(u).\\overline{x}(y).[y \\leftrightarrow w] | \\overline{z}(v).((v(i).\\overline{[\\lambda y.\\sigma.x]}_i | 0)) | x(b).[[\\lambda w:\\tau_0.w]]_b | [P]))]\n\\]\n\nwhereas the process to the right of the arrow is encoded as:\n\n\\[\n[[\\nu z](z((\\lambda w:\\tau_0.w).z((\\lambda y.\\sigma.\\lambda w:\\tau_0.w)).0 | P))] \\\\\n= (\\nu z)[\\overline{z}(w).((w(u).[[\\lambda w:\\tau_0.w]]_u | \\overline{z}(v).((v(i).[[\\lambda y.\\sigma.\\lambda w:\\tau_0.w]]_v | [P])]))]\n\\]\n\nWhile the reduction of the encoded process and the encoding of the reduct differ syntactically, they are observationally equivalent – the latter inlines the replicated process behaviour that is accessible in the former on \\( x \\). Having characterised substitution, we establish operational correspondence for the encoding.\n\nTheorem 4.6 (Operational Correspondence).\n\n1. If \\( \\Psi \\vdash M : \\tau \\) and \\( [[M]]_x \\rightarrow Q \\) then \\( M \\rightarrow^* N \\) such that \\( [[N]]_x \\approx_L Q \\)\n2. If $\\Psi; \\Gamma; \\Delta \\vdash P :: z:A$ and $\\llbracket P \\rrbracket \\rightarrow Q$ then $P \\rightarrow^+ P'$ such that $\\llbracket P' \\rrbracket \\simeq_L Q$\n\n3. If $\\Psi \\vdash M : \\tau$ and $M \\rightarrow N$ then $\\llbracket M \\rrbracket_z \\Rightarrow P$ such that $P \\simeq_L \\llbracket N \\rrbracket_z$\n\n4. If $\\Psi; \\Gamma; \\Delta \\vdash P :: z:A$ and $P \\rightarrow Q$ then $\\llbracket P \\rrbracket \\rightarrow^+ R$ with $R \\simeq_L \\llbracket Q \\rrbracket$\n\nThe process equivalence in Theorem 4.6 above need not be extended to account for data (although it would be relatively simple to do so), since the processes in the image of the encoding are fully erased of any data elements.\n\n**Back to $\\lambda$-Terms.** We extend our encoding of processes to $\\lambda$-terms to $\\text{Sess} \\pi \\lambda$. Our extended translation maps processes to linear $\\lambda$-terms, with the session type $\\tau \\land A$ interpreted as a pair type where the first component is replicated. Dually, $\\tau \\supset A$ is interpreted as a function type where the domain type is replicated. The remaining session constructs are translated as in §3.2\n\n\\[\n\\langle \\tau \\land A \\rangle \\triangleq !\\langle \\tau \\rangle \\otimes \\langle A \\rangle \\\\\n\\langle \\tau \\supset A \\rangle \\triangleq !\\langle \\tau \\rangle \\rightarrow \\langle A \\rangle \\\\\n\\langle \\tau \\rightarrow \\sigma \\rangle \\triangleq !\\langle \\tau \\rangle \\rightarrow !\\langle \\sigma \\rangle\n\\]\n\n(\\land) $\\langle x(y).P \\rangle \\triangleq \\lambda x!\\langle \\tau \\rangle.\\text{let } lx = x \\text{ in } \\langle P \\rangle$ (\\lor) $\\langle z(M).P \\rangle \\triangleq !\\langle M \\rangle \\otimes \\langle P \\rangle$\n\n(\\lor) $\\langle x(y).P \\rangle \\triangleq \\lambda x!\\langle \\tau \\rangle.\\text{let } lx = x \\text{ in } \\langle P \\rangle$\n\n(\\land) $\\langle x(M).P \\rangle \\triangleq \\langle P \\rangle \\{x!\\langle M \\rangle/\\langle M \\rangle\\}$\n\n\\[\n\\langle \\lambda x: \\tau. M \\rangle \\triangleq \\lambda x!\\langle \\tau \\rangle.\\text{let } lx = x \\text{ in } \\langle M \\rangle \\\\\n\\langle M \\cdot N \\rangle \\triangleq \\langle M \\rangle !\\langle N \\rangle \\\\\n\\langle x \\rangle \\triangleq x\n\\]\n\nThe treatment of non-linear components of processes is identical to our previous encoding: non-linear functions $\\tau \\rightarrow \\sigma$ are translated to linear functions of type $!\\langle \\tau \\rangle \\rightarrow !\\langle \\sigma \\rangle$; a process offering a session of type $\\tau \\land A$ (i.e. a process of the form $z(M).P$, typed by rule $\\land R$) is translated to a pair where the first component is the encoding of $M$ prefixed with $!$ so that it may be used non-linearly, and the second is the encoding of $P$. Non-linear variables are handled at the respective binding sites: a process using a session of type $\\tau \\land A$ is encoded using the elimination form for the pair and the elimination form for the exponential; similarly, a process offering a session of type $\\tau \\supset A$ is encoded as a $\\lambda$-abstraction where the bound variable is of type $!\\langle \\tau \\rangle$. Thus, we use the elimination form for the exponential, ensuring that the typing is correct. We illustrate our encoding:\n\n\\[\n\\langle z(x).z(x).z((\\lambda y: \\sigma.x).0) \\rangle = \\lambda x!\\langle \\tau \\rangle.\\text{let } lx = x \\text{ in } !\\langle x \\otimes !\\langle \\lambda y: \\sigma.x \\rangle \\otimes () \\rangle\n\\]\n\n\\[\n= \\lambda x!\\langle \\tau \\rangle.\\text{let } lx = x \\text{ in } !\\langle x \\otimes !\\langle \\lambda y: !\\langle \\sigma \\rangle.\\text{let } ly = y \\text{ in } x \\rangle \\otimes () \\rangle\n\\]\n\n**Properties of the Encoding.** Unsurprisingly due to the logical correspondence between natural deduction and sequent calculus presentations of logic, our encoding satisfies both type soundness and operational correspondence (c.f. Theorems 3.6, 3.8, and 3.10). The full development can be found in [52].\n\n**Relating the Two Encodings.** We prove the two encodings are mutually inverse and preserve the full abstraction properties (we write $\\equiv_\\beta$ and $\\equiv_{\\beta\\eta}$ for $\\beta$- and $\\beta\\eta$-equivalence, respectively).\n\n**Theorem 4.7 (Inverse).** If $\\Psi; \\Gamma; \\Delta \\vdash P :: z:A$ then $\\llbracket \\langle P \\rangle \\rrbracket_z \\simeq_L \\llbracket P \\rrbracket$. Also, if $\\Psi \\vdash M : \\tau$ then $\\llbracket \\langle M \\rangle_z \\rrbracket =_\\beta \\langle M \\rangle$. \n\n\nThe equivalences above are formulated between the composition of the encodings applied to $P$ (resp. $M$) and the process (resp. $\\lambda$-term) after applying the translation embedding the non-linear components into their linear counterparts. This formulation matches more closely that of §3.3, which applies to linear calculi for which the target languages of this section are a strict subset (and avoids the formalisation of process equivalence with terms). We also note that in this setting, observational equivalence and $\\beta\\eta$-equivalence coincide [3,31]. Moreover, the extensional flavour of $\\approx_L$ includes $\\eta$-like principles at the process level.\n\n**Theorem 4.8.** Let $\\vdash M : \\tau$ and $\\vdash N : \\tau$. $(\\llbracket M \\rrbracket)_z =_{\\beta\\eta} (\\llbracket N \\rrbracket)_z$. Also, let $\\vdash P :: z : A$ and $\\vdash Q :: z : A$. We have that $(\\llbracket P \\rrbracket)_z =_{\\beta\\eta} (\\llbracket Q \\rrbracket)_z$.\n\nWe establish full abstraction for the encoding of $\\lambda$-terms into processes (Theorem 4.8) in two steps: The completeness direction (i.e. from left-to-right) follows from operational completeness and strong normalisation of the $\\lambda$-calculus. The soundness direction uses operational soundness. The proof of Theorem 4.8 uses the same strategy of Theorem 3.14, appealing to the inverse theorems.\n\n### 4.3 Higher-Order Session Processes – Sess$\\pi\\lambda^+$\n\nWe extend the value-passing framework of the previous section, accounting for process-passing (i.e. the higher-order) in a session-typed setting. As shown in [50], we achieve this by adding to the data layer a contextual monad that encapsulates (open) session-typed processes as data values, with a corresponding elimination form in the process layer. We dub this calculus Sess$\\pi\\lambda^+$.\n\nThe type $\\{x_j : A_j \\vdash z : A\\}$ is the type of a term which encapsulates an open process that uses the linear channels $x_j : A_j$ and offers $A$ along channel $z$. This formulation has the added benefit of formalising the integration of session-typed processes in a functional language and forms the basis for the concurrent programming language SILL [37,50]. The typing rules for the new constructs are (for simplicity we assume no shared channels in process monads):\n\n$$\\begin{align*}\nP, Q ::= \\cdots \\mid \\{x \\leftarrow M \\leftarrow y; Q \\} & \\quad M, N ::= \\cdots \\mid \\{x \\leftarrow P \\leftarrow y_i; A_i\\} \\\\\n\\tau, \\sigma ::= \\cdots \\mid \\{x_j; A_j \\vdash z : A\\} & \\quad P, Q ::= \\cdots \\mid \\{x \\leftarrow M \\leftarrow y_i; A_i\\}\n\\end{align*}$$\n\nRule $\\{\\}$ $I$ embeds processes in the term language by essentially quoting an open process that is well-typed according to the type specification in the monadic type. Dually, rule $\\{\\}$ $E$ allows for processes to use monadic values through composition that consumes some of the ambient channels in order to provide the monadic term with the necessary context (according to its type). These constructs are discussed in substantial detail in [50]. The reduction semantics of the\nprocess construct is given by (we tacitly assume that the names \\( \\mathcal{g} \\) and \\( c \\) do not occur in \\( P \\) and omit the congruence case):\n\n\\[\n(c \\leftarrow \\{ z \\leftarrow P \\leftarrow x; A \\} \\leftarrow \\mathcal{g}; Q) \\rightarrow (\\nu c)(P[\\mathcal{g}/c][z]) \\mid Q\n\\]\n\nThe semantics allows for the underlying monadic term \\( M \\) to evaluate to a (quoted) process \\( P \\). The process \\( P \\) is then executed in parallel with the continuation \\( Q \\), sharing the linear channel \\( c \\) for subsequent interactions. We illustrate the higher-order extension with following typed process (we write \\( \\{ x \\leftarrow P \\} \\) when \\( P \\) does not depend on any linear channels and assume \\( \\vdash Q :: d: \\text{Nat} \\land 1 \\)):\n\n\\[\nP \\triangleq (\\nu c)(c(\\{d \\leftarrow Q\\}).c(x).0 \\mid c(y).d \\leftarrow y; d(n).c(n).0)\n\\]\n\nProcess \\( P \\) above gives an abstract view of a communication idiom where a process (the left-hand side of the parallel composition) sends another process \\( Q \\) which potentially encapsulates some complex computation. The receiver then \\textit{spawns} the execution of the received process and inputs from it a result value that is sent back to the original sender. An execution of \\( P \\) is given by:\n\n\\[\nP \\rightarrow (\\nu c)(c(x).0 \\mid d \\leftarrow \\{ d \\leftarrow Q \\}; d(n).c(n).0) \\rightarrow (\\nu c)(c(x).0 \\mid (vd)(Q \\mid d(n).c(n).0)) \\quad \\rightarrow^+ (\\nu c)(c(x).0 \\mid c(42).0) \\rightarrow 0\n\\]\n\nGiven the seminal work of Sangiorgi [46; such a representation naturally begs the question of whether or not we can develop a typed encoding of higher-order processes into the first-order setting. Indeed, we can achieve such an encoding with a fairly simple extension of the encoding of §4.2 to \n\n\\[\\text{Sess} \\lambda^+ \\]\n\nby observing that monadic values are processes that need to be potentially provided with extra sessions in order to be executed correctly. For instance, a term of type \\( x:A \\vdash y:B \\) denotes a process that given a session \\( x \\) of type \\( A \\) will then offer \\( y:B \\). Exploiting this observation we encode this type as the session \\( A \\rightarrow B \\), ensuring subsequent usages of such a term are consistent with this interpretation.\n\n\\[\n[[x_j:A_j \\vdash z:A]] \\triangleq \\left[ A_j \\right] \\rightarrow [A]\n\\]\n\n\\[\n[[x \\leftarrow P \\rightarrow \\mathcal{g}]\\] \\triangleq z(y_1) \\ldots z(y_n).[P[z/x]] \\quad (z \\not\\in \\text{nt}(P))\n\\]\n\n\\[\n[x \\leftarrow M \\leftarrow \\mathcal{g}; Q] \\triangleq (\\nu x)([[A]]_x \\mid \\pi(a_0).((a_0 \\leftrightarrow y_0) \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid [Q]) \\ldots))\n\\]\n\nTo encode the monadic type \\( \\left[ x_j:A_j \\vdash z:A \\right] \\), denoting the type of process \\( P \\) that is typed by \\( x_j:A_j \\vdash P :: z:A \\), we require that the session in the image of the translation specifies a sequence of channel inputs with behaviours \\( A_j \\) that make up the linear context. After the contextual aspects of the type are encoded, the session will then offer the (encoded) behaviour of \\( A \\). Thus, the encoding of the monadic type is \\( [A_0] \\rightarrow \\cdots \\rightarrow [A_n] \\rightarrow [A] \\), which we write as \\( [[A]] \\rightarrow [A] \\).\n\nThe encoding of monadic expressions adheres to this behaviour, first performing the necessary sequence of inputs and then proceeding inductively. Finally, the encoding of the elimination form for monadic expressions behaves dually, composing the encoding of the monadic expression with a sequence of outputs that instantiate the consumed names accordingly (via forwarding). The encoding of process \\( P \\) from Equation 2 is thus:\n\n\\[\n[P] = (\\nu c)([[c(d \\leftarrow Q)].c(x).0] \\mid [c(y).d \\leftarrow y; d(n).c(n).0]) = (\\nu c)(\\overline{\\pi}(w).((w(d).[Q] \\mid c(x).0)c(y).(vd)(\\overline{\\pi}(b).[b \\leftrightarrow d] \\mid d(n).\\overline{\\pi}(m).(\\overline{\\pi}(e).[c \\leftrightarrow m] \\mid 0))))\n\\]\nProperties of the Encoding. As in our previous development, we can show that our encoding for Sessπλ+ is type sound and satisfies operational correspondence. The full development is omitted but can be found in [52].\n\nWe encode Sessπλ+ into λ-terms, extending §4.2 with:\n\n\\[\n\\begin{align*}\nL \\{ x_i : A_i \\vdash z : A \\} & \\triangleq L A_i M \\Rightarrow L A M \\\\\nL x \\leftarrow M \\leftarrow y_i ; Q M & \\triangleq L Q M \\{ (L M M y_i) / x \\} \\\\\nL P M & \\triangleq \\lambda w_0 . . . . \\lambda w_n . L P M\n\\end{align*}\n\\]\n\nThe encoding translates the monadic type \\( \\{ x_i : A_i \\vdash z : A \\} \\) as a linear function \\( L A_i M \\Rightarrow L A M \\), which captures the fact that the underlying value must be provided with terms satisfying the requirements of the linear context. At the level of terms, the encoding for the monadic term constructor follows its type specification, generating a nesting of λ-abstractions that closes the term and proceeding inductively. For the process encoding, we translate the monadic application construct analogously to the translation of a linear cut, but applying the appropriate variables to the translated monadic term (which is of function type).\n\nWe remark the similarity between our encoding and that of the previous section, where monadic terms are translated to a sequence of inputs (here a nesting of λ-abstractions). Our encoding satisfies type soundness and operational correspondence, as usual. Further showcasing the applications of our development, we obtain a novel strong normalisation result for this higher-order session-calculus “for free”, through encoding to the λ-calculus.\n\n**Theorem 4.9 (Strong Normalisation).** Let \\( \\Psi ; \\Gamma ; \\Delta \\vdash P :: z : A \\). There is no infinite reduction sequence starting from \\( P \\).\n\n**Theorem 4.10 (Inverse Encodings).** If \\( \\Psi ; \\Gamma ; \\Delta \\vdash P :: z : A \\) then \\( \\{ P \\} z \\approx_L \\{ P \\} \\). Also, if \\( \\Psi \\vdash M : \\tau \\) then \\( \\{ M \\} z =_\\beta \\{ M \\} \\).\n\n**Theorem 4.11.** Let \\( \\vdash M : \\tau, \\vdash N : \\tau, \\vdash P :: z : A \\) and \\( \\vdash Q :: z : A \\). \\( \\{ M \\} =_\\beta \\{ N \\} \\) iff \\( \\{ M \\} z \\approx_L \\{ N \\} z \\) and \\( \\{ P \\} \\approx_L \\{ Q \\} \\) iff \\( \\{ P \\} =_\\beta \\{ Q \\} \\).\n\n5 Related Work and Concluding Remarks\n\nProcess Encodings of Functions. Toninho et al. [49] study encodings of the simply-typed λ-calculus in a logically motivated session π-calculus, via encodings to the linear λ-calculus. Our work differs since they do not study polymorphism nor reverse encodings; and we provide deeper insights through applications of the encodings. Full abstraction or inverse properties are not studied.\n\nSangiorgi [43] uses a fully abstract compilation from the higher-order π-calculus (HOπ) to the π-calculus to study full abstraction for Milner’s encodings of the λ-calculus. The work shows that Milner’s encoding of the lazy λ-calculus can be recovered by restricting the semantic domain of processes (the so-called restrictive approach) or by enriching the λ-calculus with suitable constants. This work was later refined in [45], which does not use HOπ and considers an operational equivalence on λ-terms called open applicative bisimulation which coincides with Lévy-Longo tree equality. The work [47] studies general conditions\nunder which encodings of the λ-calculus in the π-calculus are fully abstract wrt Lévy-Longo and Böhm Trees, which are then applied to several encodings of (call-by-name) λ-calculus. The works above deal with untyped calculi, and so reverse encodings are unfeasible. In a broader sense, our approach takes the restrictive approach using linear logic-based session typing and the induced observational equivalence. We use a λ-calculus with booleans as observables and reason with a Morris-style equivalence instead of tree equalities. It would be an interesting future work to apply the conditions in [47] in our typed setting.\n\nWadler [54] shows a correspondence between a linear functional language with session types GV and a session-typed process calculus with polymorphism based on classical linear logic CP. Along the lines of this work, Lindley and Morris [26], in an exploration of inductive and coinductive session types through the addition of least and greatest fixed points to CP and GV, develop an encoding from a linear λ-calculus with session primitives (Concurrent μGV) to a pure linear λ-calculus (Functional μGV) via a CPS transformation. They also develop translations between μCP and Concurrent μGV, extending [25]. Mapping to the terminology used in our work [17], their encodings are shown to be operationally complete, but no results are shown for the operational soundness directions and neither full abstraction nor inverse properties are studied. In addition, their operational characterisations do not compose across encodings. For instance, while strong normalisation of Functional μGV implies the same property for Concurrent μGV through their operationally complete encoding, the encoding from μCP to μGV does not necessarily preserve this property.\n\nTypes for π-calculi delineate sequential behaviours by restricting composition and name usages, limiting the contexts in which processes can interact. Therefore typed equivalences offer a coarser semantics than untyped semantics. Berger et al. [5] study an encoding of System F in a polymorphic linear π-calculus, showing it to be fully abstract based on game semantics techniques. Their typing system and proofs are more complex due to the fine-grained constraints from game semantics. Moreover, they do not study a reverse encoding.\n\nOrchard and Yoshida [33] develop embeddings to-and-from PCF with parallel effects and a session-typed π-calculus, but only develop operational correspondence and semantic soundness results, leaving the full abstraction problem open.\n\nPolymorphism and Typed Behavioural Semantics. The work of [7] studies parametric session polymorphism for the intuitionistic setting, developing a behavioural equivalence that captures parametricity, which is used (denoted as ≈ₜ) in our paper. The work [39] introduces a typed bisimilarity for polymorphism in the π-calculus. Their bisimilarity is of an intensional flavour, whereas the one used in our work follows the extensional style of Reynolds [41]. Their typing discipline (originally from [53], which also develops type-preserving encodings of polymorphic λ-calculus into polymorphic π-calculus) differs significantly from the linear logic-based session typing of our work (e.g. theirs does not ensure deadlock-freedom). A key observation in their work is the coarser nature of typed equivalences with polymorphism (in analogy to those for IO-subtyping [38]) and\ntheir interaction with channel aliasing, suggesting a use of typed semantics and encodings of the π-calculus for fine-grained analyses of program behaviour.\n\n**F-Algebras and Linear-F.** The use of initial and final (co)algebras to give a semantics to inductive and coinductive types dates back to Mendler [28], with their strong definability in System F appearing in [11] and [19]. The definability of inductive and coinductive types using parametricity also appears in [40] in the context of a logic for parametric polymorphism and later in [6] in a linear variant of such a logic. The work of [55] studies parametricity for the polymorphic linear λ-calculus of this work, developing encodings of a few inductive types but not the initial (or final) algebraic encodings in their full generality. Inductive and coinductive session types in a logical process setting appear in [51] and [26]. Both works consider a calculus with built-in recursion – the former in an intuitionistic setting where a process that offers a (co)inductive protocol is composed with another that consumes the (co)inductive protocol and the latter in a classical framework where composed recursive session types are dual each other.\n\n**Conclusion and Future Work.** This work answers the question of what kind of type discipline of the π-calculus can exactly capture and is captured by λ-calculus behaviours. Our answer is given by showing the first mutually inverse and fully abstract encodings between two calculi with polymorphism, one being the Polyπ session calculus based on intuitionistic linear logic, and the other (a linear) System F. This further demonstrates that the linear logic-based articulation of name-passing interactions originally proposed by [8] (and studied extensively thereafter e.g. [50,51,36,9,54,7,25]) provides a clear and applicable tool for message-passing concurrency. By exploiting the proof theoretic equivalences between natural deduction and sequent calculus we develop mutually inverse and fully abstract encodings, which naturally extend to more intricate settings such as process passing (in the sense of HOπ). Our encodings also enable us to derive properties of the π-calculus “for free”. Specifically, we show how to obtain adequate representations of least and greatest fixed points in Polyπ through the encoding of initial and final (co)algebras in the λ-calculus. We also straightforwardly derive a strong normalisation result for the higher-order session calculus, which otherwise involves non-trivial proof techniques [13,12,36,15]. Future work includes extensions to the classical linear logic-based framework, including multiparty session types [10,11]. Encodings of session π-calculi to the λ-calculus have been used to implement session primitives in functional languages such as Haskell (see a recent survey [32]), OCaml [34,35,24] and Scala [48]. Following this line of work, we plan to develop encoding-based implementations of this work as embedded DSLs. This would potentially enable an exploration of algebraic constructs beyond initial and final co-algebras in a session programming setting. In particular, we wish to further study the meaning of functors, natural transformations and related constructions in a session-typed setting, both from a more fundamental viewpoint but also in terms of programming patterns.\n\n**Acknowledgements.** The authors would like to thank the reviewers for their comments, suggestions and pointers to related works. This work is partially supported by EPSRC EP/K034413/1, EP/K011715/1, EP/L00058X/1, EP/N027833/1 and EP/N028201/1.\nReferences\n\nAppendix\n\nOn Polymorphic Sessions and Functions\nA Tale of Two (Fully Abstract) Encodings\n\nAdditional definitions and proofs of the main materials.\nA Appendix\n\nA.1 Additional Definitions for §2 – Structural Congruence\n\nDefinition A.1 (Structural congruence). is the least congruence relation generated by the following laws: \\( P | 0 \\equiv P; \\) \\( P \\equiv_\\alpha Q \\Rightarrow P \\equiv Q; \\) \\( P | Q \\equiv Q | P; \\) \\( P | (Q | R) \\equiv (P | Q) | R; \\) \\( (\\nu x)(\\nu y)P \\equiv (\\nu y)(\\nu x)P; \\) \\( x \\notin fn(P) \\Rightarrow P | (\\nu x)Q \\equiv (\\nu x)(P | Q); \\) \\( (\\nu x)0 \\equiv 0; \\) and \\( [x \\leftrightarrow y] \\equiv [y \\leftrightarrow x]. \\)\n\nDefinition A.2 (Extended Structural Congruence). We write \\( \\equiv! \\) for the least congruence relation on processes which results from extending structural congruence \\( \\equiv \\) (Def. A.1) with the following axioms, dubbed the Sharpened Replication Axioms [46]:\n\n1. \\((\\nu u)(!u(z).P | (\\nu y)(Q | R)) \\equiv !((\\nu y)((\\nu u)!u(z).P | Q)) | (\\nu u)!u(z).P | R))\n2. \\((\\nu u)!u(y).P | (\\nu v)((!v(z) . Q | R)) \\equiv !(\\nu v)((!v(z)!u(y).P | Q)) | (\\nu v)!u(y).P | R))\n3. \\((\\nu v)!u(y).Q | P) \\equiv !P \\quad \\text{if} \\ u \\notin fn(P)\n\nAxioms (1) and (2) represent principles for the distribution of shared servers among processes, while (3) formalises the garbage collection of shared servers which cannot be invoked by any process. The axioms embody distributivity, contraction and weakening of shared resources and are sound wrt (typed) observational equivalence [30].\n\nA.2 Additional Definitions for §2 – Typing Rules\n\nBelow we list the typing rules for the calculus of section §2. We note that the judgment \\( \\Omega \\vdash B \\text{type} \\) simply requires that free variables in \\( B \\) be in \\( \\Omega \\). Moreover, typing treats processes quotiented by structural congruence – given a well-typed process \\( \\Omega; \\Gamma; \\Delta \\vdash P :: T \\), subject reduction ensures that for all possible reductions \\( P \\xrightarrow{\\alpha} P' \\), there exists a process \\( Q \\) where \\( P' \\equiv Q \\) such that \\( \\Omega; \\Gamma; \\Delta \\vdash Q :: T \\). Related properties hold wrt general transitions \\( P \\xrightarrow{} P' \\). We refer the reader to [9,8] for additional details on this matter.\nA.3 Additional Definitions for §2 – Typed Barbed Congruence\n\n**Definition A.3 (Type-respecting Relations)**. A type-respecting relation over processes, written \\{R_S\\}_S is defined as a family of relations over processes indexed by \\(S\\). We often write \\(\\Omega\\) to refer to the whole family, and write \\(\\Omega; \\Delta \\vdash PRQ :: T\\) to denote \\(\\Omega; \\Delta \\vdash P, Q :: T\\) and \\((P, Q) \\in R_{\\Omega; \\Delta \\vdash T}\\).\nWe say that a type-respecting relation is an equivalence if it satisfies the usual properties of reflexivity, transitivity and symmetry. In the remainder of this development we often omit “type-respecting”.\n\n**Definition A.4 (τ-closed [7]).** Relation $R$ is τ-closed if $\\Omega; \\Gamma; \\Delta \\vdash PRQ :: T$ and $P \\rightarrow P'$ imply there exists a $Q'$ such that $Q \\implies Q'$ and $\\Omega; \\Gamma; \\Delta \\vdash P'RQ' :: T$.\n\nOur definition of basic observable on processes, or barb, is given below.\n\n**Definition A.5 (Barbs [7]).** Let $O_x = \\{\\pi, x, \\text{x.inl}, \\text{x.inr}, \\text{x.inl}, \\text{x.inr}\\}$ be the set of basic observables under name $x$. Given a well-typed process $P$, we write:\n\n(i) $\\text{barb}(P, \\pi)$, if $P \\xrightarrow{(y)(y)(y)} P'$; \n(ii) $\\text{barb}(P, x)$, if $P \\xrightarrow{x(A)} P'$, for some $A, P'$; \n(iii) $\\text{barb}(P, x)$, if $P \\xrightarrow{x(A)} P'$, for some $A, P'$; \n(iv) $\\text{barb}(P, x)$, if $P \\xrightarrow{y} P'$, for some $y, P'$; \n(v) $\\text{barb}(P, \\alpha)$, if $P \\xrightarrow{\\alpha} P'$, for some $P'$ and $\\alpha \\in O_x \\setminus \\{x, \\pi\\}$.\n\nGiven some $o \\in O_x$, we write $\\text{wbarb}(P, o)$ if there exists a $P'$ such that $P \\implies P'$ and $\\text{barb}(P', o)$ holds.\n\n**Definition A.6 (Barb preserving relation).** Relation $R$ is a barb preserving relation if, for every name $x$, $\\Omega; \\Gamma; \\Delta \\vdash PRQ :: T$ and $\\text{barb}(P, o)$ imply $\\text{wbarb}(Q, o)$, for any $o \\in O_x$.\n\n**Definition A.7 (Contextuality).** A relation $R$ is contextual if $\\Omega; \\Gamma; \\Delta \\vdash PRQ :: T$ implies $\\Omega; \\Gamma; \\Delta' \\vdash C[P|RC|Q] :: T'$, for every $\\Delta', T'$ and typed context $C$.\n\n**Definition A.8 (Barbed Congruence).** Barbed congruence, noted $\\cong$, is the largest equivalence on well-typed processes symmetric type-respecting relation that is τ-closed, barb preserving, and contextual.\nThe full definition for the base case of logical equivalence is given below:\n\n\\[ P \\approx_\\land Q : : x : X[\\eta : \\omega \\leftrightarrow \\omega'] \\text{ if and only if } (P, Q) \\in \\eta(X)(z) \\]\n\\[ P \\approx_\\land Q : : 1[\\eta : \\omega \\leftrightarrow \\omega'] \\text{ if } \\forall P', Q'. (P \\implies P' \\land P' \\implies Q \\land Q' \\implies Q') \\Rightarrow (P' \\equiv 0 \\land Q' \\equiv 0) \\]\n\\[ P \\approx_\\land Q : : A \\imp B[\\eta : \\omega \\leftrightarrow \\omega'] \\text{ if } \\forall P', y. (P \\overset{\\approx(y)}{\\rightarrow} P') \\Rightarrow \\exists Q'. Q \\overset{\\approx(y)}{\\rightarrow} Q' \\text{ s.t. } \\\\\n\\forall R_1, R_2, \\ R_3 \\approx_\\land R_2 :: y : A[\\eta : \\omega \\leftrightarrow \\omega'] \\\\\n(P_1)(P' | R_1) \\approx_\\land (\\forall y)(Q' | R_2) :: z : B[\\eta : \\omega \\leftrightarrow \\omega'] \\]\n\\[ P \\approx_\\land Q : : A \\land B[\\eta : \\omega \\leftrightarrow \\omega'] \\text{ if } \\forall P', y. (P \\overset{\\approx(y)}{\\rightarrow} P') \\Rightarrow \\exists Q'. Q \\overset{\\approx(y)}{\\rightarrow} Q' \\land P' \\approx_\\land Q' :: y : A[\\eta : \\omega \\leftrightarrow \\omega'] \\]\n\\[ P \\approx_\\land Q : : A \\lor B[\\eta : \\omega \\leftrightarrow \\omega'] \\text{ if } \\forall P'. (P \\overset{\\approx(y)}{\\rightarrow} P') \\Rightarrow \\exists Q'. Q \\overset{\\approx(y)}{\\rightarrow} Q' \\lor P' \\approx_\\land Q' :: y : B[\\eta : \\omega \\leftrightarrow \\omega'] \\]\n\nA.4 Additional Definitions for §2 – Logical Equivalence\nA.5 Typing Rules for Linear-F\n\n\\[\n\\begin{align*}\n\\text{(VAR)} & \\quad \\text{(-I)} \\\\\n\\Omega, \\Gamma; \\Delta, \\Delta', A \\vdash M : B & \\quad \\Omega, \\Gamma; \\Delta, \\Delta' \\vdash \\lambda x: A. M : A \\rightarrow B \\\\\n\\Omega; \\Gamma; \\Delta \\vdash x : A & \\quad \\Omega; \\Delta, \\Delta' \\vdash M N : B \\\\\n\\text{(\\&I)} & \\quad \\text{(-E)} \\\\\n\\Omega, \\Gamma; \\Delta \\vdash M : A & \\quad \\Omega, \\Gamma; \\Delta \\vdash M : A \\rightarrow B \\\\\n\\Omega; \\Gamma; \\Delta, \\Delta' \\vdash A \\otimes B & \\quad \\Omega; \\Gamma, \\Delta, \\Delta'; \\Delta' \\vdash N : B'\n\\end{align*}\n\\]\n\nLemma A.9. 1. Let \\(\\Omega; \\Gamma; \\Delta, x : A \\vdash M : B\\) and \\(\\Omega; \\Gamma; \\Delta \\vdash N : A\\). We have that \\(\\Omega; \\Gamma; \\Delta, \\Delta' \\vdash \\eta x(y)(\\|M\\|_z \\|N\\|_x) : z:B\\).\n\n2. Let \\(\\Omega; \\Gamma; \\Delta \\vdash M : B\\) and \\(\\Omega; \\Gamma; \\Delta \\vdash N : A\\). We have that \\(\\Omega; \\Gamma; \\Delta \\vdash \\eta u(x)(\\|M\\|_z \\|N\\|_u) : z:B\\).\n\nProof. By induction on the structure of \\(M\\), exploiting the fact that commuting conversions and \\(\\equiv\\) are sound \\(\\approx\\) equivalences. See Lemma [1.5] for further details.\n\nA.6 Operational Correspondence for \\([\\cdot]_z\\)\n\nThe results follow from a straightforward extension to the development in [49].\n\nA.7 Additional Definitions for § 3.2 — Encoding on Typing Derivations\n\nThe encoding on typing derivations is given in Figures [5] and [6] (for readability purposes, the processes are highlighted in blue). The encoding makes use of the two admissible substitution principles denoted by the following rules:\n\n\\[\n\\begin{align*}\n\\text{(subst)} & \\quad \\text{(subst')} \\\\\n\\Omega; \\Gamma; \\Delta, \\Delta', \\Delta_1 \\vdash M \\{N/x\\} : A & \\quad \\Omega; \\Gamma; \\Delta, \\Delta' \\vdash M \\{N/u\\} : A \\\\\n\\Omega; \\Gamma; \\Delta_1, \\Delta_2 \\vdash M : A & \\quad \\Omega; \\Gamma; \\Delta \\vdash M : A \\rightarrow B \\\\\n\\Omega; \\Gamma; \\Delta_1, \\Delta_2 \\vdash \\lambda x : A. M : A \\rightarrow B & \\quad \\Omega; \\Gamma; \\Delta \\vdash M \\{N/x\\} : A \\\\\n\\end{align*}\n\\]\nA.8 Proofs for §3.2 – Encoding from Poly感兴趣 to Linear-F\n\n**Theorem 3.6.** If $\\Omega; \\Gamma; \\Delta \\vdash P :: z:A$ then $\\langle \\Omega \\rangle; \\langle \\Gamma \\rangle; \\langle \\Delta \\rangle \\vdash \\langle P \\rangle :: A$.\n\n**Proof.** Straightforward induction.\n\n**Theorem 3.8 (Operational Completeness).** Let $\\Omega; \\Gamma; \\Delta \\vdash P :: z:A$. If $P \\rightarrow Q$ then $\\langle P \\rangle \\rightarrow^\\ast \\langle Q \\rangle$.\n\n**Proof.** Induction on typing and case analysis on the possibility of reduction.\n\n**Case:**\n\n$$\n\\frac{\n\\begin{array}{c}\n\\Omega; \\Gamma; \\Delta_1 \\vdash P_1 :: x:A \\\\\n\\Omega; \\Gamma; \\Delta_2, x:A \\vdash P_2 :: z:C\n\\end{array}\n}{\\Omega; \\Gamma; \\Delta_1, \\Delta_2 \\vdash (\\nu x)(P_1 \\mid P_2) :: z:C}\n$$\n\nwhere $P_1 \\rightarrow P'_1$ or $P_2 \\rightarrow P'_2$.\n\n**Subcase:** $P_1 \\rightarrow P'_1$\n\n$$\n\\langle (\\nu x)(P_1 \\mid P_2) \\rangle = \\langle P'_2 \\rangle \\{ \\langle P'_1 \\rangle / x \\} \\quad \\text{by definition}\n$$\n\n**Subcase:** $P_2 \\rightarrow P'_2$\n\n$$\n\\langle (\\nu x)(P_1 \\mid P_2) \\rangle = \\langle P'_2 \\rangle \\{ \\langle P'_1 \\rangle / x \\} \\quad \\text{by definition}\n$$\n\n**Case:**\n\n$$\n\\frac{\n\\begin{array}{c}\n\\Omega; \\Gamma; \\Delta_1 \\vdash x(y).P_1 :: x:A \\rightarrow B \\\\\n\\Omega; \\Gamma; \\Delta_2, x:A \\vdash (\\nu y)x(y).Q_1 \\mid Q_2 :: z:C\n\\end{array}\n}{\\Omega; \\Gamma; \\Delta_1, \\Delta_2 \\vdash (\\nu x)((\\nu y)x(y).Q_1 \\mid Q_2) :: z:C}\n$$\n\nby reduction\n\n$$\n\\langle (\\nu x)((\\nu y)x(y).Q_1 \\mid Q_2) \\rangle = \\langle Q_2 \\rangle \\{ \\langle P_1 \\rangle \\{ \\langle Q_1 \\rangle / y \\} / x \\} \\quad \\text{by definition}\n$$\n\n**Case:**\n\n$$\n\\frac{\n\\begin{array}{c}\n\\Omega; \\Gamma; \\Delta_1 \\vdash (\\nu y)x(y).P_1 \\mid P_2 :: x:A \\otimes B \\\\\n\\Omega; \\Gamma; \\Delta_2, x:A \\otimes B \\vdash x(y).Q_1 :: z:C\n\\end{array}\n}{\\Omega; \\Gamma; \\Delta_1, \\Delta_2 \\vdash ((\\nu y)x(y).P_1 \\mid P_2) \\mid x(y).Q_1 :: z:C}\n$$\n\nby reduction\n\n$$\n\\langle ((\\nu y)x(y).P_1 \\mid P_2) \\mid x(y).Q_1 \\rangle = \\langle Q_1 \\rangle \\{ \\langle P_2 \\rangle \\{ \\langle P_1 \\rangle / x \\} \\} \\quad \\text{by def.}\n$$\n\nlet $x \\otimes y = \\langle P_2 \\rangle \\otimes \\langle P_1 \\rangle$ in $\\langle Q_1 \\rangle \\{ \\langle P_2 \\rangle / x \\} \\{ \\langle P_1 \\rangle / y \\}$\nCase: \\[\n\\left(\\text{cut}^1\\right) \\frac{\\Omega; \\Gamma; \\vdash P_1 :: x:A \\quad \\Omega; \\Gamma; \\vdash \\Delta \\vdash \\lambda y. u(x).Q_1 :: z:C}{\\Omega; \\Gamma; \\vdash \\Delta \\vdash \\lambda u(x).P_1 | (\\nu x)u(x).Q_1 :: z:C}\n\\]\n\n\\((\\nu u)(\\lambda u(x).P_1 | (\\nu x)u(x).Q_1) \\rightarrow (\\nu u)(\\lambda u(x).P_1 | (\\nu x)(P_1 | Q_1))\\) by reduction\n\n\\(\\{Q_1\\}(\\lambda u(x).P_1 | (\\nu x)(P_1 | Q_1)) = \\{Q_1\\}(\\lambda u(x).P_1 | (\\nu x)u(x).Q_1)\\) by definition\n\n\\(\\{Q_1\\}(\\lambda u(x).P_1 | (\\nu x)(P_1 | Q_1)) = \\{Q_1\\}(\\lambda u(x).P_1 | (\\nu x)u(x).Q_1)\\) by definition\n\nCase:\n\n\\[\n\\left(\\text{cut}\\right) \\frac{\\Omega, \\Gamma; \\Delta_1 \\vdash x(Y).P_1 :: \\forall Y. A \\quad \\Omega, \\Gamma; \\Delta_2, x : \\forall Y. A \\vdash x(B).Q_1 :: z:C}{\\Omega, \\Gamma; \\Delta_1, \\Delta_2 \\vdash (\\nu x)(x(Y).P_1 | x(B).Q_1) :: z:C}\n\\]\n\n\\((\\nu x)(x(Y).P_1 | x(B).Q_1) \\rightarrow (\\nu x)(P_1 \\{B_1 / Y\\} | Q_1)\\) by reduction\n\n\\(\\{Q_1\\}(\\lambda x(x(Y).P_1 | x(B).Q_1)) = \\{Q_1\\}(\\lambda x(x(B)/x))\\) by definition\n\n\\(\\{Q_1\\}(\\lambda x(x(B)/x)) \\rightarrow \\beta \\{Q_1\\}(\\lambda x(x(B)/x))\\) by definition\n\n\\(\\{Q_1\\}(\\lambda x(x(B)/x)) \\rightarrow \\beta \\{Q_1\\}(\\lambda x(x(B)/x))\\) by definition\n\nCase:\n\n\\[\n\\left(\\text{cut}\\right) \\frac{\\Omega, \\Gamma; \\Delta_1 \\vdash x(B).P_1 :: \\exists Y. A \\quad \\Omega, \\Gamma; \\Delta_2, x : \\exists Y. A \\vdash x(Y).Q_1 :: z:C}{\\Omega, \\Gamma; \\Delta_1, \\Delta_2 \\vdash (\\nu x)(x(B).P_1 | x(Y).Q_1) :: z:C}\n\\]\n\n\\((\\nu x)(x(B).P_1 | x(Y).Q_1) \\rightarrow (\\nu x)(P_1 | Q_1 \\{B/Y\\})\\) by reduction\n\n\\(\\{Q_1\\}(\\lambda x(x(B).P_1 | x(Y).Q_1)) = \\{Q_1\\}(\\lambda x(x(Y)/x)) \\rightarrow \\beta \\{Q_1\\}(\\lambda x(x(Y)/x))\\) by definition\n\n\\(\\{Q_1\\}(\\lambda x(x(Y)/x)) \\rightarrow \\beta \\{Q_1\\}(\\lambda x(x(Y)/x))\\) by definition\n\n\\(\\{Q_1\\}(\\lambda x(x(Y)/x)) \\rightarrow \\beta \\{Q_1\\}(\\lambda x(x(Y)/x))\\) by definition\n\n**Theorem 3.10 (Operational Soundness).** Let \\(\\Omega, \\Gamma; \\Delta \\vdash P :: A \\land \\langle Q \\rangle \\rightarrow M\\), there exists \\(Q\\) such that \\(P \\rightarrow^* Q\\) and \\(\\langle Q \\rangle =_\\alpha M\\).\n\n**Proof.** By induction on typing.\n\nCase:\n\n\\(\\left(\\text{cut}\\right) \\frac{\\Omega, \\Gamma; \\Delta_1 \\vdash P_1 :: y:A \\quad \\Omega, \\Gamma; \\Delta_2, x : B \\vdash P_2 :: z:C}{\\Omega, \\Gamma; \\Delta_1, \\Delta_2, x : A \\rightarrow B \\vdash (\\nu y)x(y).P_1 | P_2 :: z:C}\n\\]\n\n\\(\\{Q(\\nu y)x(y).P_1 | P_2\\} = \\{Q\\}(\\lambda x(Q_0)/x)\\) with \\(\\{P_2\\}(\\lambda x(Q_0)/x) = M \\rightarrow M'\\) by assumption\n\n**Subcase:** \\(M \\rightarrow M'\\) due to reducibility in \\(\\langle P_1 \\rangle\\)\n\n\\(\\{P_1\\} \\rightarrow M_0\\) by assumption\n\n\\(\\exists Q_0\\) such that \\(P_1 \\rightarrow^* Q_0\\) and \\(\\langle Q_0 \\rangle =_\\alpha M_0\\) by i.h.\n\n\\(\\{Q(\\nu y)x(y).P_1 | P_2\\} = \\{Q\\}(\\lambda x(Q_0)/x)\\) with \\(\\{P_2\\}(\\lambda x(Q_0)/x) = M \\rightarrow M'\\) by compatibility of \\(\\Rightarrow\\)\n\n**Subcase:** \\(M \\rightarrow M'\\) due to reducibility in \\(\\langle P_2 \\rangle\\)\n\n\\(\\{P_2\\} \\rightarrow M_0\\) by assumption\n\n\\(\\exists Q_0\\) such that \\(P_2 \\rightarrow^* Q_0\\) and \\(\\langle Q_0 \\rangle = M_0\\) by i.h.\n\n\\(\\{Q(\\nu y)x(y).P_1 | P_2\\} = \\{Q\\}(\\lambda x(Q_0)/x)\\) with \\(\\{P_2\\}(\\lambda x(Q_0)/x) = M \\rightarrow M'\\) by compatibility of \\(\\Rightarrow\\)\n\n\\(\\{Q(\\nu y)x(y).P_1 | Q_0\\} = \\{Q_0\\}(\\lambda x(Q_0)/x)\\) with \\(\\{P_2\\}(\\lambda x(Q_0)/x) = M \\rightarrow M'\\) by compatibility of \\(\\Rightarrow\\)\nCase:\n\\[(\\text{copy}) \\quad \\Omega; \\Gamma; u:A; \\Delta, x:A \\vdash P_1 :: z:C \\quad \\Omega; \\Gamma; u:A; \\Delta \\vdash (\\nu x)u(x).P_1 :: z:C \\]\n\n\\[\\langle(\\nu x)u(x).P_1\\rangle = \\langle P_1\\rangle\\{u/x\\} = M \\rightarrow M' \\quad \\text{by assumption} \\]\n\\[\\langle P_1\\rangle \\rightarrow M_0 \\quad \\text{by inversion on } \\rightarrow \\]\n\\[\\exists Q_0 \\text{ such that } P_1 \\rightarrow^* Q_0 \\text{ and } \\langle Q_0\\rangle =_\\alpha M_0 \\quad \\text{by i.h.} \\]\n\\[\\langle(\\nu x)u(x).P_1\\rangle \\rightarrow^* (\\nu x)u(x).Q_0 \\quad \\text{by compatibility} \\]\n\\[\\langle(\\nu x)u(x).Q_0\\rangle = \\langle Q_0\\rangle\\{u/x\\} = M_0\\{u/x\\} \\]\n\nCase:\n\\[(\\forall L) \\quad \\Omega \\vdash B \\quad \\Omega; \\Gamma; \\Delta, x:A\\{B/X\\} \\vdash P_1 :: z:C \\quad \\Omega; \\Gamma; \\Delta, x:\\forall X.A \\vdash x(B).P_1 :: z:C \\]\n\n\\[\\langle x(B).P_\\|\\rangle = \\langle P_\\|\\rangle\\{x[B]/x\\} \\quad \\text{with } \\langle P_\\|\\rangle\\{x[B]/x\\} \\rightarrow M \\quad \\text{by assumption} \\]\n\\[\\langle P_\\|\\rangle \\rightarrow M_0 \\quad \\text{by inversion} \\]\n\\[\\exists Q_0 \\text{ such that } P_1 \\rightarrow^* Q_0 \\text{ and } \\langle Q_0\\rangle =_\\alpha M_0 \\quad \\text{by i.h.} \\]\n\\[x(B).P_\\| \\rightarrow^* x(B).Q_0 \\quad \\text{by compatibility} \\]\n\\[\\langle x(B).Q_0\\rangle = \\langle Q_0\\rangle\\{x[B]/x\\} = M_0\\{x[B]/x\\} \\]\n\nCase:\n\\[(\\text{cut}) \\quad \\Omega; \\Gamma; \\Delta_1 \\vdash P_1 :: x:A \\quad \\Omega; \\Gamma; \\Delta_2 \\vdash x:A \\vdash P_2 :: z:C \\quad \\Omega; \\Gamma; \\Delta_1, \\Delta_2 \\vdash (\\nu x)(P_1 \\mid P_2) :: z:C \\]\n\n\\[\\langle(\\nu x)(P_1 \\mid P_2)\\rangle = \\langle P_2\\rangle\\{\\langle P_1\\rangle/x\\} \\quad \\text{with } \\langle P_2\\rangle\\{\\langle P_1\\rangle/x\\} = M \\rightarrow M' \\quad \\text{by assumption} \\]\n\nSubcase: \\(M \\rightarrow M'\\) due to redex in \\(\\langle P_1\\rangle\\)\n\\[\\langle P_1\\rangle \\rightarrow M_0 \\quad \\text{by assumption} \\]\n\\[\\exists Q_0 \\text{ such that } P_1 \\rightarrow^* Q_0 \\text{ and } \\langle Q_0\\rangle =_\\alpha M_0 \\quad \\text{by i.h.} \\]\n\\[\\langle(\\nu x)(P_1 \\mid P_2)\\rangle \\rightarrow^* (\\nu x)(Q_0 \\mid P_2) \\quad \\text{by reduction} \\]\n\\[\\langle(\\nu x)(Q_0 \\mid P_2)\\rangle = \\langle P_2\\rangle\\{\\langle Q_0\\rangle/x\\} = \\langle P_2\\rangle\\{M_0/x\\} \\]\n\nSubcase: \\(M \\rightarrow M'\\) due to redex in \\(\\langle P_2\\rangle\\)\n\\[\\langle P_2\\rangle \\rightarrow M_0 \\quad \\text{by assumption} \\]\n\\[\\exists Q_0 \\text{ such that } P_2 \\rightarrow^* Q_0 \\text{ and } \\langle Q_0\\rangle = M_0 \\quad \\text{by i.h.} \\]\n\\[\\langle(\\nu x)(P_1 \\mid P_2)\\rangle \\rightarrow^* (\\nu x)(Q_0 \\mid P_2) \\quad \\text{by compatibility} \\]\n\\[\\langle(\\nu x)(P_1 \\mid Q_0)\\rangle = \\langle Q_0\\rangle\\{\\langle P_1\\rangle/x\\} = M_0\\{\\langle P_1\\rangle/x\\} \\]\n\nSubcase: \\(M \\rightarrow M'\\) where the redex arises due to the substitution of \\(\\langle P_1\\rangle\\) for \\(x\\)\n\nSubsubcase: Last rule of deriv. of \\(P_2\\) is a left rule on \\(x\\): \nIn all cases except \\(!\\), a top-level process reduction is exposed (viz. Theorem 3.8). If last rule is \\(!\\), then either \\(x\\) does not occur in \\(P_2\\) and we conclude by \\(\\rightarrow\\).\n\nSubsubcase: Last rule of deriv. of \\(P_2\\) is not a left rule on \\(x\\): \nFor rule \\((id)\\) we have a process reduction immediately. In all other cases either there is no possible \\(\\beta\\)-redex or we can conclude via compatibility of \\(\\rightarrow\\).\n\nCase:\n\\[(\\text{cut}^t) \\quad \\Omega; \\Gamma; \\vdash P_1 :: x:A \\quad \\Omega; \\Gamma; \\vdash P_2 :: z:C \\quad \\Omega; \\Gamma; \\Delta \\vdash (\\nu u)(\\!u(x).P_1 \\mid P_2) :: z:C \\]\n\n\\[ ((v\\mu)(u(x) \\cdot P_1 | P_2)) = \\{P_2\\} \\{\\{P_1\\} / u\\} \\] with \\(\\{P_2\\} \\{\\{P_1\\} / u\\} \\rightarrow M\\) by assumption\n\n**Subcase:** \\( M \\rightarrow M' \\) due to redex in \\(\\{P_1\\}\\)\n\n\\(\\{P_1\\} \\rightarrow M_0\\)\n\n\\(\\exists Q_0\\) such that \\(P_1 \\rightarrow^* Q_0\\) and \\(\\{Q_0\\} = M_0\\)\n\n\\((v\\mu)(u(x) \\cdot P_1 | P_2)) \\rightarrow^* (v\\mu)(u(x) \\cdot Q_0 | P_2)\\)\n\n\\(\\{\\{\\{Q_0\\} / u\\}\\}\\) by compatibility\n\n\\(\\{\\{\\{Q_0\\} / u\\}\\}\\) by i.h.\n\n\\((v\\mu)(u(x) \\cdot Q_0 | P_2)\\) = \\(\\{P_2\\} \\{\\{Q_0\\} / u\\} = \\{P_2\\} \\{M_0 / u\\}\\)\n\n**Subcase:** \\( M \\rightarrow M' \\) due to redex in \\(\\{P_2\\}\\)\n\n\\(\\{P_2\\} \\rightarrow M_0\\)\n\n\\(\\exists Q_0\\) such that \\(P_2 \\rightarrow^* Q_0\\) and \\(\\{Q_0\\} = M_0\\)\n\n\\((v\\mu)(u(x) \\cdot P_1 | P_2)) \\rightarrow^* (v\\mu)(u(x) \\cdot Q_0)\\)\n\n\\(\\{\\{\\{Q_0\\} / u\\}\\}\\) by compatibility\n\n\\(\\{\\{\\{Q_0\\} / u\\}\\}\\) by i.h.\n\n\\((v\\mu)(u(x) \\cdot P_1 | Q_0)\\) = \\(\\{P_1\\} \\{\\{Q_0\\} / u\\} = M_0 \\{\\{P_1\\} / u\\}\\)\n\n**Subcase:** \\( M \\rightarrow M' \\) where the redex arises due to the substitution of \\(L P_1 M\\) for \\(u\\)\n\nIf last rule in deriv. of \\(P_2\\) is copy then we have \\(=\\) terms in 0 process reductions.\n\nOtherwise, the result follows by compatibility of \\(\\rightarrow\\).\n\nIn all other cases the \\(\\lambda\\)-term in the image of the translation does not reduce.\n\n### A.9 Proofs for § 3.3 – Inversion and Full Abstraction\n\nThe proofs below rely on the fact that all commuting conversions of linear logic are sound observational equivalences in the sense of \\(\\approx\\).\n\n**Theorem 3.11 (Inverse).** If \\(\\Omega; \\Gamma; \\Delta \\vdash M : A\\) then \\(\\Omega; \\Gamma; \\Delta \\vdash \\langle\\{M\\}_z\\rangle \\cong M : A\\). Also, if \\(\\Omega; \\Gamma; \\Delta \\vdash P :: z : A\\) then \\(\\Omega; \\Gamma; \\Delta \\vdash \\langle\\{P\\}_z\\rangle \\approx \\langle P \\rangle :: z : A\\).\n\nWe prove (1) and (2) above separately.\n\n**Theorem A.10.** If \\(\\Omega; \\Gamma; \\Delta \\vdash M : A\\) then \\(\\Omega; \\Gamma; \\Delta \\vdash \\langle\\{M\\}_z\\rangle \\cong M : A\\)\n\n**Proof.** By induction on the given typing derivation.\n\n**Case:** Linear variable\n\n\\(\\langle\\{x\\}_z\\rangle = x \\cong x\\)\n\n**Case:** Unrestricted variable\n\n\\(\\langle\\{u\\}_z\\rangle = (\\nu x)u(x) \\cdot [x \\leftrightarrow z]\\)\n\nby def.\n\n\\(\\langle((\\nu x)u(x) \\cdot [x \\leftrightarrow z])\\rangle = u \\cong u\\)\n\n**Case:** \\(\\lambda\\)-abstraction\n\n\\(\\langle\\lambda x. M\\rangle_z = z(x) \\cdot \\langle\\{M\\}_z\\rangle\\)\n\nby def.\n\n\\(\\langle z(x) \\cdot \\langle\\{M\\}_z\\rangle\\rangle = \\lambda x. \\langle\\{M\\}_z\\rangle \\cong \\lambda x. M\\)\n\nby i.h. and congruence\n\n**Case:** Application\n\\[\n\\llbracket MN \\rrbracket_z = (\\nu x)(\\llbracket M \\rrbracket_x | (\\nu y)x(y).(\\llbracket N \\rrbracket_y | [x \\leftrightarrow z])) \\quad \\text{by def.}\n\\]\n\\[\n\\llbracket (\\nu x)((\\llbracket M \\rrbracket_x | (\\nu y)x(y).(\\llbracket N \\rrbracket_y | [x \\leftrightarrow z])))) = \\llbracket \\llbracket M \\rrbracket_z \\rrbracket \\llbracket \\llbracket N \\rrbracket_y \\rrbracket \\quad \\text{by def.}\n\\]\n\\[\n\\llbracket \\llbracket M \\rrbracket_z \\rrbracket \\llbracket \\llbracket N \\rrbracket_y \\rrbracket \\cong M N \\quad \\text{by i.h. and congruence}\n\\]\n\n**Case:** Exponential\n\n\\[\n\\llbracket ![z(x)] \\rrbracket_x = ![z(x)] \\quad \\text{by def.}\n\\]\n\\[\n\\llbracket ![z(x)] \\rrbracket_x = ![\\llbracket M \\rrbracket_z] \\cong \\llbracket ![M]_z \\rrbracket \\quad \\text{by def, i.h. and congruence}\n\\]\n\n**Case:** Exponential elim.\n\n\\[\n\\llbracket ![u = M \\text{ in } N] \\rrbracket_z = (\\nu x)(\\llbracket M \\rrbracket_x | [N]_z \\{x/u\\}) \\quad \\text{by def.}\n\\]\n\\[\n\\llbracket (\\nu x)((\\llbracket M \\rrbracket_x | [N]_z \\{x/u\\})) \\rrbracket = \\text{let } u = \\llbracket M \\rrbracket_z \\text{ in } \\llbracket [N]_z \\rrbracket \\quad \\text{by def.}\n\\]\n\\[\n\\text{let } u = \\llbracket M \\rrbracket_z \\text{ in } \\llbracket [N]_z \\rrbracket \\cong \\text{let } u = M \\text{ in } N \\quad \\text{by congruence and i.h.}\n\\]\n\n**Case:** Multiplicative Pairing\n\n\\[\n\\llbracket (M \\otimes N) \\rrbracket_z = (\\nu y)(\\llbracket M \\rrbracket_y | \\llbracket N \\rrbracket_z) \\quad \\text{by def.}\n\\]\n\\[\n\\llbracket (\\nu y)(\\llbracket M \\rrbracket_y | \\llbracket N \\rrbracket_z) \\rrbracket = \\llbracket \\llbracket M \\rrbracket_y \\otimes \\llbracket N \\rrbracket_z \\rrbracket \\quad \\text{by def.}\n\\]\n\\[\n\\llbracket \\llbracket M \\rrbracket_y \\otimes \\llbracket N \\rrbracket_z \\rrbracket \\cong \\llbracket (M \\otimes N) \\rrbracket_z \\quad \\text{by i.h. and congruence}\n\\]\n\n**Case:** Mult. Pairing Elimination\n\n\\[\n\\llbracket \\text{let } x \\otimes y = M \\text{ in } N \\rrbracket_z = (\\nu y)((\\llbracket M \\rrbracket_x | x(y).[N]_z) \\quad \\text{by def.}\n\\]\n\\[\n\\llbracket (\\nu y)((\\llbracket M \\rrbracket_x | x(y).[N]_z)) \\rrbracket = \\text{let } x \\otimes y = \\llbracket M \\rrbracket_x \\text{ in } \\llbracket [N]_z \\rrbracket \\quad \\text{by def.}\n\\]\n\\[\n\\text{let } x \\otimes y = \\llbracket M \\rrbracket_x \\text{ in } \\llbracket [N]_z \\rrbracket \\cong \\text{let } x \\otimes y = M \\text{ in } N \\quad \\text{by i.h. and congruence}\n\\]\n\n**Case:** A-abstraction\n\n\\[\n\\llbracket AX.M \\rrbracket_z = AX.\\llbracket M \\rrbracket_z \\cong AX.M \\quad \\text{by i.h. and congruence}\n\\]\n\n**Case:** Type application\n\n\\[\n\\llbracket \\llbracket M \\rrbracket_z \\rrbracket [A] \\cong \\llbracket M[A] \\rrbracket \\quad \\text{by i.h. and congruence}\n\\]\n\n**Case:** Existential Intro.\n\n\\[\n\\llbracket \\text{pack } A \\text{ with } \\llbracket M \\rrbracket_z \\rrbracket = \\text{pack } A \\text{ with } \\llbracket M \\rrbracket_z \\cong \\text{pack } A \\text{ with } M \\quad \\text{by i.h. and congruence}\n\\]\n\n**Case:** Existential Elim.\n\n\\[\n\\llbracket \\text{let } (X, y) = M \\text{ in } N \\rrbracket_z = \\text{let } (X, y) = \\llbracket M \\rrbracket_z \\text{ in } \\llbracket [N]_z \\rrbracket \\cong \\text{let } (X, y) = M \\text{ in } N \\quad \\text{by i.h. and congruence}\n\\]\nTheorem A.11. If $\\Omega; \\Gamma; \\Delta \\vdash P :: z: A$ then $\\Omega; \\Gamma; \\Delta \\vdash [\\langle P \\rangle]_z \\approx_L P :: z: A$\n\nProof. By induction on the given typing derivation.\n\nCase: $(id)$ or any right rule\n\nImmediately by definition in the case of $(id)$ and by i.h. and congruence in all other cases.\n\nCase: $\\rightarrow L$\n\n\\[\n\\begin{align*}\n\\langle (\\nu y)x(y).P | Q \\rangle &= \\langle Q \\rangle \\{ (x \\langle P \\rangle) / x \\} \\\\\n[\\langle Q \\rangle \\{ (x \\langle P \\rangle) / x \\} ]_z &\\approx_L (\\nu a)(\\langle x \\langle P \\rangle \\rangle)_a \\cup [\\langle Q \\rangle ]_z \\{ a / x \\}) \\\\\n\\rightarrow (\\nu a)(\\langle (\\nu y)(x \\leftrightarrow y) \\cdot w(a) \\rangle \\cdot [\\langle P \\rangle ]_y \\{ w \\leftrightarrow a \\}) &\\cup [\\langle Q \\rangle ]_z \\{ a / x \\}) \\\\\n&\\approx_L (\\nu y)x(y).\\langle P | Q \\rangle \\quad \\text{commuting conversion + reduction}\n\\end{align*}\n\\]\n\nby definition in the case of $(id)$ and by i.h. and congruence in all other cases.\n\nCase: $\\otimes L$\n\n\\[\n\\begin{align*}\n\\langle x.y.P \\rangle &= \\langle x \\otimes y = x \\rangle \\in \\langle P \\rangle \\\\\n[\\langle x \\otimes y = x \\rangle \\in \\langle P \\rangle ]_z &\\approx_L (\\nu w)(\\{ x \\leftrightarrow w \\} \\cup [\\langle y \\rangle ]_y \\cdot [\\langle P \\rangle ]_z) \\\\\n\\rightarrow x(y).\\langle P \\rangle &\\approx_L x(y).P \\\\\n&\\quad \\text{by i.h. and congruence}\n\\end{align*}\n\\]\n\nCase: $! L$\n\n\\[\n\\begin{align*}\n\\langle P \\{ x/u \\} \\rangle &= \\langle let ! u = x \\rangle \\in \\langle P \\rangle \\\\\n[\\langle let ! u = x \\rangle \\in \\langle P \\rangle ]_z &\\approx_L (\\nu w)(\\{ x \\leftrightarrow w \\} \\cup [\\langle P \\rangle ]_z \\{ w / u \\}) \\\\\n\\rightarrow [\\langle P \\rangle ]_z \\{ x/u \\} &\\approx_L P \\{ x/u \\} \\\\\n&\\quad \\text{by i.h.}\n\\end{align*}\n\\]\n\nCase: copy\n\n\\[\n\\begin{align*}\n\\langle (\\nu x) u(\\langle P \\{ x/u \\} \\rangle) \\rangle &= \\langle (\\nu x) u(\\langle P \\rangle \\{ x/u \\} ) \\rangle \\\\\n[\\langle (\\nu x) u(\\langle P \\rangle \\{ x/u \\} ) \\rangle ]_z &\\approx_L (\\nu x)(\\nu w)(\\{ w \\leftrightarrow x \\} \\cup [\\langle P \\rangle ]_z) \\\\\n\\rightarrow (\\nu x)(\\nu w)(\\{ w \\leftrightarrow x \\} \\cup P) &\\approx_L (\\nu x) u(\\langle P \\rangle \\{ x/u \\} ) \\\\\n&\\quad \\text{by i.h. and congruence}\n\\end{align*}\n\\]\n\nCase: $\\forall L$\n\n\\[\n\\begin{align*}\n\\langle x(B).P \\rangle &= \\langle \\{ x(B) \\} / x \\rangle \\\\\n[\\langle \\{ x(B) \\} / x \\rangle ]_z &\\approx_L (\\nu a)(\\langle x(B) \\rangle_a \\cup [\\langle P \\rangle ]_z \\{ a / x \\}) \\\\\n\\rightarrow (\\nu a)(\\langle x(B) \\rangle_a \\cup [\\langle P \\rangle ]_z \\{ a / x \\}) &\\approx_L x(B).\\langle P \\rangle \\\\\n&\\quad \\text{by definition of $\\approx_L$ for open processes (i.e. closing for $u:A$ and observing that no actions on $z$ are blocked)}\n\\end{align*}\n\\]\n\nCase: $\\exists L$\nTheorem 3.14 (Full Abstraction).\n\nBy Theorem 3.13 (Soundness), we have that\n\n\\[ x \\models \\lambda (Y). P \\triangleq \\lambda (y : \\mathcal{Y}). (x \\leftrightarrow y) \\] \\[ \\frac{\\mathcal{R}(\\text{let } y \\leftarrow y \\triangleright y((x \\leftrightarrow y).\\mathcal{R}(P))_z)}{\\mathcal{R}(x)(Y).P} \\]\n\nby reduction\n\n\\[ \\equiv \\mathcal{L} x(Y).P \\]\n\nby i.h. + congruence\n\nCase: cut\n\n\\[ \\langle (\\nu x) (P \\mid Q) \\rangle = \\langle Q \\rangle \\{ (P)/x \\} \\]\n\nby definition\n\n\\[ \\langle (Q) \\{ (Q)/x \\} \\rangle \\equiv \\mathcal{L} (\\nu y) (\\langle (P)/y \\rangle \\mid \\langle (Q)/y \\rangle \\{ (y/x) \\}) \\]\n\nby Lemma A.9 with y fresh\n\n\\[ \\equiv (\\nu x) (P \\mid Q) \\]\n\nby i.h. + congruence and \\( \\equiv_{\\alpha} \\)\n\nCase: cut 1\n\n\\[ \\#((\\nu u)!\\mathcal{L}(\\mathcal{L}(P \\mid Q)) = \\langle Q \\rangle \\{ (P)/u \\} \\]\n\nby definition\n\n\\[ \\langle (Q) \\{ (P)/u \\} \\rangle \\equiv \\mathcal{L} (\\nu u)!\\mathcal{L}(\\mathcal{L}(P \\mid Q) \\{ (v/u) \\}) \\]\n\nby Lemma A.9\n\n\\[ \\approx \\mathcal{L} (\\nu u)!\\mathcal{L}(\\mathcal{L}(P \\mid Q) \\{ (v/u) \\}) \\]\n\nby i.h. + congruence and \\( \\equiv_{\\alpha} \\)\n\nLemma A.12. \\( M \\upharpoonright \\top \\iff \\mathcal{L} [M] \\equiv \\mathcal{L} [\\top] \\equiv z : 2 \\)\n\nProof. By operational correspondence.\n\nTheorem 3.13 (Full Abstraction). \\( \\Omega; \\Gamma; \\Delta \\vdash M \\equiv N \\vdash A \\iff \\Omega; \\Gamma; \\Delta \\vdash \\mathcal{L} [M] \\equiv \\mathcal{L} [N] \\equiv z : A \\)\n\nProof. (Soundness, \\( \\leftarrow \\)) Since \\( \\equiv \\) is the largest consistent congruence compatible with the booleans, let \\( M \\downarrow N \\) if \\( \\mathcal{L} [M] \\equiv \\mathcal{L} [N] \\). We show that \\( \\mathcal{R} \\) is one such relation.\n\n1. (Congruence) Since \\( \\equiv \\) is a congruence, \\( \\mathcal{R} \\) is a congruence.\n\n2. (Reduction-closed) Let \\( M \\rightarrow M' \\) and \\( \\mathcal{L} [M] \\equiv \\mathcal{L} [N] \\). Then we have by operational correspondence (Theorem 3.4) that \\( \\mathcal{L} [M] \\rightarrow^* P \\) such that \\( M' \\triangleq P \\) and we have that \\( P \\approx \\mathcal{L} [M'] \\) hence \\( \\mathcal{L} [M] \\approx \\mathcal{L} [N] \\), thus \\( \\mathcal{R} \\) is reduction closed.\n\n3. (Compatible with the booleans) Follows from Lemma A.12\n\n(Completeness, \\( \\rightarrow \\)) Assume to the contrary that \\( M \\equiv N \\vdash A \\) and \\( \\mathcal{L} [M] \\not\\equiv \\mathcal{L} [N] \\). This means we can find a distinguishing context \\( R \\) such that \\( (\\nu z, \\tilde{x})(\\mathcal{L} [M] \\mid R) \\approx \\mathcal{L} [\\top] : y : 2 \\) and \\( (\\nu z, \\tilde{x})(\\mathcal{L} [N] \\mid R) \\approx \\mathcal{L} [\\bot] : y : 2 \\). By Fullness (Theorem 3.12), we have that there exists some \\( L \\) such that \\( \\mathcal{L} [L] \\approx R \\), thus:\n\n\\[ (\\nu z, \\tilde{x})(\\mathcal{L} [M] \\mid [L]_y) \\approx \\mathcal{L} [\\top] \\equiv y : 2 \\] \\[ (\\nu z, \\tilde{x})(\\mathcal{L} [N] \\mid [L]_y) \\approx \\mathcal{L} [\\bot] \\equiv y : 2 \\]\n\nBy Theorem 3.13 (Soundness), we have that \\( L[M] \\equiv \\top \\) and \\( L[N] \\equiv \\bot \\) and thus \\( L[M] \\not\\equiv L[N] \\) which contradicts \\( M \\equiv N \\vdash A \\).\n\nTheorem 3.14 (Full Abstraction). \\( \\Omega; \\Gamma; \\Delta \\vdash P \\equiv L Q \\vdash z : A \\iff \\Omega; \\Gamma; \\Delta \\vdash \\langle P \\rangle \\equiv \\langle Q \\rangle : A \\).\nProof. (Soundness, $\\leftarrow$) Let $M = (P)$ and $N = (Q)$. By Theorem 3.13 (Completeness) we have $\\lbrack M \\rbrack_z \\approx_L \\lbrack N \\rbrack_z$. Thus by Theorem 3.11 we have: $\\lbrack M \\rbrack_z = \\lbrack \\lbrack P \\rbrack \\rbrack_z \\approx_L P$ and $\\lbrack N \\rbrack_z = \\lbrack \\lbrack Q \\rbrack \\rbrack_z \\approx_L Q$. By compatibility with observational equivalence we have $P \\approx_L Q :: z : A$.\n\n(Completeness, $\\rightarrow$) From $P \\approx_L Q :: z : A$, Theorem 3.11 and compatibility with observational equivalence we have $\\lbrack \\lbrack P \\rbrack \\rbrack_z \\approx_L \\lbrack \\lbrack Q \\rbrack \\rbrack_z :: z : A$. Let $(P) = M$ and $(Q) = N$. We have by Theorem 3.13 (Soundness) that $M \\equiv N : A$ and thus $(P) \\approx_L (Q) : A$.\n\nA.10 Proofs for § 4.2 – Communicating Values\n\nLemma A.13 (Type Soundness of Encoding).\n\n1. If $\\Theta \\vdash \\Gamma : \\sigma$ then $\\lbrack \\Theta \\rbrack : \\Gamma \\vdash \\lbrack M \\rbrack_z :: z : \\sigma$\n\n2. If $\\Theta ; \\Gamma ; \\Delta \\vdash \\Pi : A$ then $\\lbrack \\Theta \\rbrack ; \\lbrack \\Pi \\rbrack ; \\lbrack \\Delta \\rbrack \\vdash \\lbrack \\Pi \\rbrack :: z : A$\n\nProof. Straightforward induction.\n\nLemma 4.5 (Compositionality). Let $\\Theta, x : \\tau \\vdash M : \\sigma$ and $\\Psi \\vdash N : \\tau$. We have that $\\lbrack M \\{N/x\\} \\rbrack_z \\approx_L (\\nu x)(\\lbrack M \\rbrack_z \\triangleright x(\\nu x).\\lbrack N \\rbrack_y)$\n\nProof. By induction on the typing for $M$. We make use of the fact that $\\approx_L$ includes $\\equiv_!$.\n\nCase: $M = y$ with $y = x$\n\n$\\lbrack M \\{N/x\\} \\rbrack_z = \\lbrack [N]_z \\triangleright x(\\nu x)(\\lbrack y \\leftrightarrow z \\triangleright x(y).\\lbrack N \\rbrack_y) \\triangleright y \\leftrightarrow z \\triangleright x(y).\\lbrack N \\rbrack_y)$\n\nby definition\n\n$\\rightarrow^+(\\nu x)(\\lbrack N \\rbrack_z \\triangleright x(y).\\lbrack N \\rbrack_y)$\n\nby the reduction semantics\n\n$\\approx_L \\lbrack [N]_z \\triangleright x(y).\\lbrack N \\rbrack_y)$\n\nCase: $M = y$ with $y \\neq x$\n\n$\\lbrack M \\{N/x\\} \\rbrack_z = \\lbrack \\lbrack N \\rbrack_y \\triangleright x(y).\\lbrack N \\rbrack_y \\rightarrow^+(\\nu x)(\\lbrack N \\rbrack_y \\triangleright x(y).\\lbrack N \\rbrack_y)$\n\nby definition\n\n$\\approx_L \\nu x \\triangleright x(y).\\lbrack N \\rbrack_y)$\n\nby $\\equiv_!$\n\nCase: $M = M_1 M_2$\n\n$\\lbrack M_1 M_2 \\{N/x\\} \\rbrack_z = \\lbrack M_1 \\{N/x\\} M_2 \\{N/x\\} \\rbrack_z = (\\nu y)(\\lbrack M_1 \\{N/x\\} \\rbrack_y \\triangleright x(y).\\lbrack N \\rbrack_y)$\n\nby definition\n\n$\\rightarrow^+(\\nu x)(\\lbrack M_1 M_2 \\rbrack_z \\triangleright x(y).\\lbrack N \\rbrack_y)$\n\nby definition\n\n$\\approx_L (\\nu x)(\\lbrack M_1 \\rbrack_y \\triangleright x(y).\\lbrack N \\rbrack_y)$\n\nby i.h.\n\n$\\approx_L \\nu x \\triangleright x(y).\\lbrack N \\rbrack_y)$\n\nby i.h.\nProof.\n\nCase: \\( \\lambda y: \\tau_0. M' \\)\n\n\\[\n\\begin{align*}\n&[[\\lambda y: \\tau_0. M'] \\{N/x\\}]_z = Z(y) \\cdot [[M' \\{N/x\\}]_z \\\\\n&\\ (\\nu x)([[M']_z \\ | x(y), [[N]_y]) = (\\nu x)(Z(y) \\cdot [[M']_z \\ | x(y), [[N]_y]) \\quad \\text{by definition} \\\\\n&[[M' \\{N/x\\}]_z] \\approxL (\\nu x)([[M']_z \\ | x(w), [[N]_w]) \\quad \\text{by i.h.} \\\\\n&[[\\lambda y: \\tau_0. M' \\{N/x\\}]_z] \\approxL Z(y) \\cdot (\\nu x)([[M']_z \\ | x(w), [[N]_w]) \\quad \\text{by congruence} \\\\\n&\\approxL (\\nu x)(Z(y) \\cdot [[M']_z \\ | x(w), [[N]_w]) \\quad \\text{by commuting conversion}\n\\end{align*}\n\\]\n\nTheorem A.14 (Operational Completeness).\n\n1. If \\( \\Psi \\vdash M : \\tau \\) and \\( M \\rightarrow N \\) then \\( [[M]]_z \\Longrightarrow P \\) such that \\( P \\approxL [[N]]_z \\)\n\n2. If \\( \\Psi; \\Gamma \\vdash P :: z:A \\) and \\( P \\rightarrow Q \\) then \\( [[P]] \\rightarrow^+ R \\) with \\( R \\approxL [[Q]] \\)\n\nProof. We proceed by induction on the given derivation and case analysis on the reduction.\n\nCase: \\( M = \\lambda x: \\tau. M' \\) with \\( M \\rightarrow M' \\{N'/x\\} \\)\n\n\\[\n\\begin{align*}\n[[M]]_y = (\\nu y)([[\\lambda x: \\tau. M']_y \\ | \\ !y(x). [[M]_y \\ | \\ y \\leftrightarrow z]) = \\\\\n(\\nu y)(y(x).[[M']_y \\ | \\ !y(x). [[M]_y \\ | \\ y \\leftrightarrow z]) \\quad \\text{by definition of } [[-]] \\\\\n\\rightarrow^+ (\\nu x)([[M']_z \\ | \\ !x(w). [[N]_w]) \\quad \\text{by the reduction semantics} \\\\\n\\approxL [[M' \\{N'/x\\}]_z] \\quad \\text{by Lemma 4.5}\n\\end{align*}\n\\]\n\nCase: \\( M = M_1 M_2 \\) with \\( M \\rightarrow M'_1 M'_2 \\) by \\( M_1 \\rightarrow M'_1 \\)\n\n\\[\n\\begin{align*}\n[[M_1 M_2]]_z = (\\nu y)([[M_1 M_2]]_y \\ | \\ !y(x). [[M_1 M_2]_y \\ | \\ y \\leftrightarrow z]) = \\\\\n(\\nu y)(y(x).[[M_1 M_2]]_y \\ | \\ !y(x). [[M_1 M_2]_y \\ | \\ y \\leftrightarrow z]) \\quad \\text{by definition} \\\\\n[[M_1 M_2]]_y \\Longrightarrow P'_1 \\text{ such that } P'_1 \\approxL [[M'_1 M'_2]]_y \\quad \\text{by i.h.} \\\\\n[[M_1 M_2]]_z \\Longrightarrow (\\nu y)(P'_1 \\ | \\ !y(x). [[M_1 M_2]_y \\ | \\ y \\leftrightarrow z]) \\text{ by reduction semantics} \\\\\n\\approxL (\\nu y)([[M'_1 M'_2]]_y \\ | \\ !y(x). [[M_1 M_2]_y \\ | \\ y \\leftrightarrow z]) \\quad \\text{by congruence}\n\\end{align*}\n\\]\n\nCase: \\( P = (\\nu x)(x(M).P' \\ | \\ x(y).Q') \\) with \\( P \\rightarrow (\\nu x)(P' \\ | \\ Q' \\{M/y\\}) \\)\n\n\\[\n\\begin{align*}\n[[P]] = (\\nu x)(![y(x). [[M]_y \\ | \\ P' \\ | \\ x(y), Q']] = \\\\\n[[P]] \\rightarrow (\\nu x)(y(x). [[M]_y \\ | \\ P' \\ | \\ Q']) \\quad \\text{by the reduction semantics} \\\\\n[[(\\nu x)(P' \\ | \\ Q' \\{M/y\\})] \\approxL (\\nu x)([[P'] \\ | \\ Q' \\{M/y\\}]) \\quad \\text{by definition} \\\\\n\\approxL (\\nu x, y)([[P'] \\ | \\ Q']) \\quad \\text{by Lemma 4.5 and congruence}\n\\end{align*}\n\\]\n\nAll remaining cases follow straightforwardly by induction.\n\nTheorem A.15 (Operational Soundness).\n\n1. If \\( \\Psi \\vdash M : \\tau \\) and \\( [[M]]_z \\rightarrow Q \\) then \\( M \\rightarrow \\rightarrow N \\) such that \\( [[N]]_z \\approxL Q \\)\n\n2. If \\( \\Psi; \\Gamma \\vdash P :: z:A \\) and \\( [[P]] \\rightarrow Q \\) then \\( P \\rightarrow \\rightarrow P' \\) such that \\( [[P']] \\approxL Q \\)\n\nProof. By induction on the given derivation and case analysis on the reduction step.\n\nCase: \\( M = M_1 M_2 \\) with \\( [[M_1]]_y \\rightarrow R \\)\nLemma A.16 (Type Soundness of Encoding).\n\n1. If $\\Psi; \\Gamma; \\Delta \\vdash P :: z : A$ then $\\langle \\Psi \\rangle; \\langle \\Gamma \\rangle; \\langle \\Delta \\rangle \\vdash \\langle P \\rangle : \\langle A \\rangle$\n\n2. If $\\Psi \\vdash M : \\tau$ then $\\langle \\Psi \\rangle ; \\vdash \\langle M \\rangle : \\langle \\tau \\rangle$\nProof. Straightforward induction.\n\nLemma A.17 (Compositionality).\n\n1. If $\\Psi; x:\\tau; \\Gamma; \\Delta \\vdash P :: z:B$ and $\\Psi \\vdash M : \\tau$ then $\\langle P\\{M/x\\} \\rangle =_{\\alpha} \\langle P \\rangle \\{\\{M\\}/x\\}$\n2. If $\\Psi; x:\\tau; \\Gamma; \\Delta \\vdash M : \\sigma$ and $\\Psi \\vdash N : \\tau$ then $\\langle M\\{N/x\\} \\rangle =_{\\alpha} \\langle M \\rangle \\{\\{N\\}/x\\}$\n\nProof. Straightforward induction.\n\nTheorem A.18 (Operational Soundness).\n\n1. If $\\Psi; \\Gamma; \\Delta \\vdash P :: z:A$ and $\\langle P \\rangle \\rightarrow M$ then $P \\rightarrow^* Q$ such that $M =_{\\alpha} \\langle Q \\rangle$\n2. If $\\Psi \\vdash M : \\tau$ and $\\langle M \\rangle \\rightarrow N$ then $M \\rightarrow^+ M'$ such that $N =_{\\alpha} \\langle M' \\rangle$\n\nProof. We proceed by induction on the given reduction and case analysis on typing.\n\nCase: $\\langle P_0 \\rangle \\{\\{x!(M_0)\\}/x\\} \\rightarrow M$\n\n$\\langle P_0 \\rangle \\{\\{x!(M_0)\\}/x\\} \\rightarrow M'\\{\\{x!(M_0)\\}/x\\}$ by operational semantics\n\n$P_0 \\mapsto P_0'$ with $P'_0 =_\\beta M'$ by i.h.\n\n$x(M_0).P_0 \\mapsto x(M_0).P'_0$ by extended reduction\n\n$\\langle x(M_0).P_0 \\rangle = \\langle P'_0 \\rangle \\{\\{x!(M_0)\\}/x\\}$ by definition\n\n$=_{\\alpha} M'\\{\\{x!(M_0)\\}/x\\}$ by congruence\n\nThe other cases are covered by our previous result for the reverse encoding of processes.\n\nCase: $\\langle M_0 \\rangle \\{\\{M_1\\} \\rangle \\rightarrow M_0' \\{\\{M_1\\} \\rangle$\n\n$\\langle M_0 \\rangle \\rightarrow M_0'$ by inversion\n\n$M_0 \\rightarrow^+ M''_0$ such that $M''_0 =_{\\alpha} \\langle M''_0 \\rangle$ by i.h.\n\n$M_0 M_1 \\rightarrow^+ M''_0 M_1$ by operational semantics\n\n$\\langle M''_0 M_1 \\rangle = \\langle M''_0 \\rangle \\{\\{M_1\\} \\rangle =_{\\alpha} M''_0 \\{\\{M_1\\} \\rangle$ by definition and by congruence\n\nCase: $(\\lambda x:!\\tau_0.M_0) \\{\\{M_1\\} \\rangle \\rightarrow \\lambda x=!\\{M_1\\} \\{\\{M_0\\} \\rangle$\n\n$(\\lambda x:!\\tau_0.M_0) \\{\\{M_1\\} \\rangle \\rightarrow \\lambda x=!\\{M_1\\} \\{\\{M_0\\} \\rangle$ by inversion and operational semantics\n\nlet $!x =!\\{M_1\\} \\{\\{M_0\\} \\rangle \\rightarrow \\{M_0\\} \\{\\{M_1\\} \\rangle$ by operational semantics\n\n$=_{\\alpha} \\langle M_0\\{M_1/x\\} \\rangle$ by Lemma A.17\n\nTheorem A.19 (Operational Completeness).\n\n1. If $\\Psi; \\Gamma; \\Delta \\vdash P :: z:A$ and $P \\rightarrow Q$ then $\\langle P \\rangle \\rightarrow^*_\\beta \\langle Q \\rangle$\n2. If $\\Psi \\vdash M : \\tau$ and $M \\rightarrow N$ then $\\langle M \\rangle \\rightarrow^+ \\langle N \\rangle$\n\nProof. We proceed by induction on the given reduction.\n\nCase: $(\\nu x)(x(M).P_1 \\mid x(y).P_2) \\rightarrow (\\nu x)(P_1 \\mid P_2\\{M/x\\})$ with $P$ typed via cut of $\\wedge R$ and $\\wedge L$\nTheorem 4.7 (Inverse). If \\( \\Psi; \\Gamma; \\Delta \\vdash P : z : A \\) then \\( \\llbracket P \\rrbracket_z \\approx_L \\llbracket P \\rrbracket \\). Also, if \\( \\Psi \\vdash M : \\tau \\) then \\( \\llbracket M \\rrbracket_z =_\\beta \\llbracket M \\rrbracket \\).\n\nWe establish the proofs of the two statements separately:\n\n### Theorem A.20 (Inverse Encodings – Processes). If \\( \\Psi; \\Gamma; \\Delta \\vdash P : z : A \\) then \\( \\llbracket P \\rrbracket_z \\approx_L \\llbracket P \\rrbracket \\)\n\n**Proof.** By induction on typing.\n\nCase: \\( \\land R \\)\n\n\\[\nP = z \\langle M \\rangle . P_0\n\\]\n\n\\[\n\\langle P \\rangle = \\langle \\llbracket M \\rrbracket \\otimes \\llbracket P_0 \\rrbracket \\rangle\n\\]\n\n\\[\n\\llbracket z \\langle M \\rangle \\otimes \\langle P_0 \\rangle \\rrbracket_z = \\llbracket \\lambda x. (\\llbracket x \\otimes \\llbracket M \\rrbracket_u \\mid \\llbracket P_0 \\rrbracket_z) \\rrbracket\n\\]\n\n\\[\n\\approx_L \\llbracket \\lambda x. (\\llbracket x \\otimes \\llbracket M \\rrbracket_u \\mid \\llbracket P_0 \\rrbracket_z) \\rrbracket\n\\]\n\nCase: \\( \\land L \\)\n$P = x(y).P_0$\n\n$(P) = \\lambda y \\otimes x = x \\in \\text{let } !y = y \\in (P_0)$\n\n$\\Rightarrow [\\text{let } y \\otimes x = x \\in \\text{let } !y = y \\in (P_0)] z = x(y).[\\text{let } (P_0)] z$\n\n$[x(y).P_0] z = x(y).[P_0]$\n\n$\\approx_L x(y).[P_0] z$\n\nCase: $\\exists R$\n\n$P = x(y).P_0$\n\n$(P) = \\lambda x:!(\\tau).\\text{let } !x = x \\in (P_0)$\n\n$\\Rightarrow [\\lambda x:!(\\tau).\\text{let } !x = x \\in (P_0)] z = x(y).[P_0] z$\n\n$[x(y).P_0] z = x(y).[P_0]$\n\n$\\approx_L x(y).[P_0] z$\n\nCase: $\\exists L$\n\n$P = x(M).P_0$\n\n$(P) = \\{P_0\\}(x :: \\text{let } !M)/x$\n\n$\\Rightarrow [(P_0)(x :: \\text{let } !M)/x] z = \\nu a([x :: !M] a \\mid [P_0] z [a/x])$\n\nby Lemma [A.9]\n\n$\\Rightarrow \\nu a((\\nu b)(([x :: !M] a \\mid [b \\leftrightarrow a]) \\mid [P_0] z [a/x]))$\n\nby definition\n\n$\\Rightarrow \\nu a((\\nu b)((x \\leftrightarrow b) \\mid b(c).((\\nu c)([c :: (M)] c \\mid [b \\leftrightarrow a]) \\mid [P_0] z [a/x]))$\n\nby reduction semantics\n\n$\\Rightarrow \\nu a((\\nu c).([c :: (M)] c \\mid [P_0] z [a/x]))$\n\nby commuting conversion and reduction\n\n$\\Rightarrow \\nu a([c :: (M)] c \\mid [P_0] z [a/x])$\n\nby i.h. and congruence\n\n$\\approx_L \\nu a([c :: (M)] c \\mid [P_0] z [a/x])$\n\nby i.h. and congruence\n\n$\\approx_L [P] = \\nu a([c :: (M)] c \\mid [P_0] z [a/x])$\n\nby i.h. and congruence\n\nTheorem A.21 (Inverse Encodings – $\\lambda$-terms). If $\\Psi \\vdash M : \\tau$ then $(\\llbracket M \\rrbracket_\\beta) = \\beta (\\llbracket M \\rrbracket)$\n\nProof. By induction on typing.\n\nCase: Variable\n\n$[M] z = x(y).[y \\leftrightarrow z]$\n\nby definition\n\n$\\llbracket x(y).[y \\leftrightarrow z] \\rrbracket_\\beta = x$\n\nby definition\n\nCase: $\\lambda$-abstraction\n\n$[\\lambda x:\\tau_0.M_0] z = x(z).[M_0] z$\n\nby definition\n\n$\\llbracket \\lambda x:!(\\tau_0).\\text{let } !x = x \\in (\\llbracket M_0 \\rrbracket) z \\rrbracket_\\beta = \\lambda x:!(\\tau_0).\\text{let } !x = x \\in (\\llbracket M_0 \\rrbracket)$\n\nby i.h. and congruence\n\nCase: Application\n\n$[(M_0 M_1) z = ((\\nu y)(\\llbracket M_0 \\rrbracket_\\nu \\cdot \\nu x)(\\cdot x(w).\\llbracket M_1 \\rrbracket_\\nu \\cdot [y \\leftrightarrow z])][y \\leftrightarrow z]$}\n\nby definition\n\n$\\llbracket (((\\nu y)(\\llbracket M_0 \\rrbracket_\\nu \\cdot \\nu x)(\\cdot x(w).\\llbracket M_1 \\rrbracket_\\nu \\cdot [y \\leftrightarrow z]))\\{y \\leftrightarrow z\\}) / y \\rrbracket_\\beta$\n\nby definition\n\n$\\approx_L \\llbracket (M_0 M_1) z \\rrbracket_\\beta = \\llbracket (M_0 M_1) z \\rrbracket_\\beta$\n\nby i.h. and congruence\nLemma A.22. Let \\( \\cdot \\vdash M : \\tau \\) and \\( \\cdot \\vdash V : \\tau \\) with \\( V \\not\\rightarrow_{\\beta\\eta} \\). \\( [M]_z \\approx_L [V]_z \\) iff \\( \\langle M \\rangle \\rightarrow_{\\beta\\eta}^* \\langle V \\rangle \\)\n\nProof.\n\n\\((\\Leftarrow)\\)\n\n\\(\\langle M \\rangle \\rightarrow_{\\beta\\eta}^* \\langle V \\rangle \\)\n\nby assumption\n\nIf \\( \\langle M \\rangle = \\langle V \\rangle \\) then \\([V]_z \\approx_L [V]_z \\)\n\nby reflexivity\n\nIf \\( \\langle M \\rangle \\rightarrow_{\\beta\\eta}^* \\langle V \\rangle \\) then \\([M]_z \\implies P \\approx_L [V]_z \\)\n\nby Lemma A.14\n\nby closure under reduction\n\n\\(\\Rightarrow\\)\n\n\\(V = \\alpha \\lambda x : \\tau_0 . \\Sigma_0\\)\n\nby inversion\n\n\\(\\langle V \\rangle = \\lambda x : \\tau_0 . \\Sigma_0. \\langle \\Sigma_0 \\rangle\\)\n\nby definition\n\n\\([V]_z = \\Sigma_0\\) \\(\\langle \\Sigma_0 \\rangle\\)\n\nby definition\n\n\\(M : \\tau_0 \\to \\tau_1\\)\n\nby inversion\n\n\\(\\langle M \\rangle \\rightarrow_{\\beta\\eta}^* \\langle V \\rangle \\)\n\nby strong normalisation\n\nWe proceed by induction on the length \\( n \\) of the (strong) reduction:\n\nSubcase: \\( n = 0 \\)\n\n\\(\\langle M \\rangle = \\lambda x : \\tau_0 . M_0\\)\n\nby inversion\n\n\\(M_0 = \\Sigma_0\\)\n\nby uniqueness of normal forms\n\nSubcase: \\( n = n' + 1 \\)\n\n\\(\\langle M \\rangle \\rightarrow_{\\beta\\eta} M' \\)\n\nby assumption\n\n\\([M]_z \\implies P \\approx_L [M']_z \\)\n\nby Lemma A.14\n\n\\([M']_z \\approx_L [V]_z \\)\n\nby closure under reduction\n\n\\(\\langle M' \\rangle \\rightarrow_{\\beta\\eta}^* \\langle V \\rangle \\)\n\nby i.h.\n\n\\(\\langle M \\rangle \\rightarrow_{\\beta\\eta}^* \\langle V \\rangle \\)\n\nby transitive closure\n\nTheorem 4.8. Let \\( \\cdot \\vdash M : \\tau \\) and \\( \\cdot \\vdash N : \\tau \\). \\( \\langle M \\rangle \\equiv_{\\beta\\eta} \\langle N \\rangle \\) iff \\([M]_z \\approx_L [N]_z \\).\n\nAlso, let \\( \\cdot \\vdash P : z : A \\) and \\( \\cdot \\vdash Q : z : A \\). We have that \\([P]_z \\approx_L [Q]_z \\) iff \\(\\langle P \\rangle =_{\\beta\\eta} \\langle Q \\rangle \\).\n\nWe establish the proof of the two statements separately.\n\nTheorem A.23. Let \\( \\cdot \\vdash M : \\tau \\) and \\( \\cdot \\vdash N : \\tau \\). We have that \\( \\langle M \\rangle =_{\\beta\\eta} \\langle N \\rangle \\) iff \\([M]_z \\approx_L [N]_z \\)\n\nProof.\n\nCompleteness (\\(\\Rightarrow\\))\n\n\\(\\langle M \\rangle =_{\\beta\\eta} \\langle N \\rangle \\) iff \\( \\exists S . \\langle M \\rangle \\rightarrow_{\\beta\\eta}^* S \\) and \\( \\langle N \\rangle \\rightarrow_{\\beta\\eta}^* S \\)\n\nAssume \\(\\rightarrow^*\\) is of length 0, then: \\(\\langle M \\rangle =_{\\alpha} \\langle N \\rangle, [M]_z \\equiv [N]_z \\) and thus \\([M]_z \\approx_L [N]_z \\)\n\nAssume \\(\\rightarrow^+\\) is of some length \\( > 0 \\):\n\n\\(\\langle M \\rangle \\rightarrow_{\\beta\\eta}^+ S \\) and \\( \\langle N \\rangle \\rightarrow_{\\beta\\eta}^+ S \\), for some \\( S \\)\n\nby assumption\n\n\\([M]_z \\rightarrow_{\\beta\\eta}^+ P \\approx_L [S]_z \\) and \\([N]_z \\rightarrow_{\\beta\\eta}^+ Q \\approx_L [S]_z \\)\n\nby Lemma A.14\n\n\\([M]_z \\approx_L [S]_z \\) and \\([N]_z \\approx_L [S]_z \\)\n\nby closure under reduction\n\n\\([M]_z \\approx_L [N]_z \\)\n\nby transitivity\n\nSoundness (\\(\\Leftarrow\\))\n\n\\([M]_z \\approx_L [N]_z \\)\n\nby assumption\n\nSuffices to show: \\( \\exists S . \\langle M \\rangle \\rightarrow_{\\beta\\eta}^* S \\) and \\( \\langle N \\rangle \\rightarrow_{\\beta\\eta}^* S \\)\n\\( \\langle N \\rangle \\rightarrow_{\\beta_N}^* S' \\not\\rightarrow \\) by strong normalisation\n\nWe proceed by induction on the length \\( n \\) of the reduction:\n\n**Subcase: \\( n = 0 \\)**\n\n\\( \\llbracket M \\rrbracket_z \\approx_L \\llbracket S' \\rrbracket_z \\)\n\n\\( \\langle M \\rangle \\rightarrow_{\\beta_N}^* \\langle N \\rangle \\) by assumption\n\n**Subcase: \\( n = n' + 1 \\)**\n\n\\( \\langle N \\rangle \\rightarrow_{\\beta_N} S' \\) by assumption\n\n\\( \\llbracket N \\rrbracket_z \\rightarrow P \\approx_L \\llbracket S' \\rrbracket_z \\)\n\n\\( \\llbracket M \\rrbracket_z \\approx_L \\llbracket S' \\rrbracket_z \\) by closure under reduction\n\n\\( \\langle M \\rangle =_{\\beta_N} \\langle S' \\rangle \\) by i.h.\n\n\\( \\langle M \\rangle =_{\\beta_N} \\langle N \\rangle \\) by transitivity\n\n**Theorem A.24.** Let \\( \\vdash P :: z:A \\) and \\( \\vdash Q :: z:A \\). We have that \\( \\llbracket P \\rrbracket \\approx_L \\llbracket Q \\rrbracket \\) iff \\( \\langle P \\rangle =_{\\beta_N} \\langle Q \\rangle \\)\n\n**Proof.**\n\n(\\( \\leq \\))\n\nLet \\( M = \\langle P \\rangle \\) and \\( N = \\langle Q \\rangle \\):\n\n\\( \\llbracket M \\rrbracket_z \\approx_L \\llbracket N \\rrbracket_z \\) by Theorem 4.8 (Completeness)\n\n\\( \\llbracket M \\rrbracket_z = \\llbracket P \\rrbracket_z \\approx_L \\llbracket P \\rrbracket \\) and \\( \\llbracket N \\rrbracket_z = \\llbracket Q \\rrbracket_z \\) by Theorem 4.7\n\n\\( \\llbracket P \\rrbracket \\approx_L \\llbracket Q \\rrbracket \\) by compatibility of logical equivalence\n\n(\\( \\geq \\))\n\n\\( \\llbracket \\langle P \\rangle \\rrbracket_z \\approx_L \\llbracket \\langle Q \\rangle \\rrbracket_z \\) by Theorem 4.7 and compatibility of logical equivalence\n\n\\( \\langle P \\rangle =_{\\beta_N} \\langle Q \\rangle \\) by Theorem 4.8 (Soundness)\n\nA.11 Proofs for § 4.3 – Higher-Order Session Processes\n\n**Theorem A.25 (Operational Soundness).**\n\n1. If \\( \\Psi; M : \\tau \\) and \\( \\llbracket M \\rrbracket_z \\rightarrow Q \\) then \\( M \\rightarrow^+ N \\) such that \\( \\llbracket N \\rrbracket_z \\approx_L Q \\)\n2. If \\( \\Psi; \\Gamma; \\Delta \\vdash P :: z:A \\) and \\( \\llbracket P \\rrbracket \\rightarrow Q \\) then \\( P \\rightarrow^+ P' \\) such that \\( \\llbracket P' \\rrbracket \\approx_L Q \\)\n\n**Proof.** By induction on the given reduction.\n\n**Case:** \\( (\\nu x)(P_0 \\mid \\pi(a_0).([a_0 \\leftrightarrow y_0] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid P_1) \\ldots)) \\rightarrow (\\nu x)(P_0' \\mid \\pi(a_0).([a_0 \\leftrightarrow y_0] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid P_1) \\ldots)) \\)\n\n\\( P = x \\leftarrow M_0 \\leftarrow \\gamma; P_2 \\) with \\( \\llbracket M_0 \\rrbracket_z = P_0 \\) and \\( \\llbracket P_1 \\rrbracket = P_2 \\) by inversion\n\n\\( M_0 \\rightarrow^+ M'_0 \\) with \\( \\llbracket M'_0 \\rrbracket_z = \\llbracket P'_0 \\rrbracket \\) by i.h.\n\n\\( (x \\leftarrow M_0 \\leftarrow \\gamma; P_2) \\rightarrow^+ (x \\leftarrow M'_0 \\leftarrow \\gamma; P_2) \\) by reduction semantics\n\n\\( \\llbracket x \\leftarrow M'_0 \\leftarrow \\gamma; P_2 \\rrbracket = (\\nu x)(\\llbracket M_0 \\rrbracket_z \\mid \\pi(a_0).([a_0 \\leftrightarrow y_0] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid P_1) \\ldots)) \\) by definition\n\n\\( \\approx_L (\\nu x)(P_0' \\mid \\pi(a_0).([a_0 \\leftrightarrow y_0] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid P_1) \\ldots)) \\) by congruence\n\n**Case:** \\( (\\nu x)(x(a_0).\\ldots.x(a_n).P_0 \\mid \\pi(a_0).([a_0 \\leftrightarrow y_0] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid P_1) \\ldots)) \\rightarrow (\\nu x,a_0)(x(a_1).\\ldots.x(a_n).P_0 \\mid [a_0 \\leftrightarrow y_0] \\mid x(a_1).([a_1 \\leftrightarrow y_1] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid P_1) = Q \\)\nProof. By induction on the given reduction.\n\nTheorem A.27 (Operational Soundness).\n\n1. If $\\Psi \\vdash M : \\tau$ and $M \\rightarrow N$ then $[M]_x \\Rightarrow P$ such that $P \\approx \\subseq N$ by inversion\n2. If $\\Psi ; \\Gamma; \\Delta \\vdash P :: z:A$ and $P \\rightarrow Q$ then $[P] \\rightarrow^+ R$ with $R \\approx \\subseq Q$\n\nProof. By induction on the given reduction.\n\nCase: $x \\leftarrow M \\leftarrow \\overline{\\text{\\Psi}}; Q \\rightarrow x \\leftarrow M' \\leftarrow \\overline{\\text{\\Psi}}; Q$ from $M \\rightarrow M'$\n\n$$[x \\leftarrow M \\leftarrow \\overline{\\text{\\Psi}}; Q] = (\\nu x)([M]_x | \\overline{\\pi}(a_0).([a_0 \\leftrightarrow y_0] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid [\\overline{Q}] \\cdots)))$$\n\nby definition\n\n$$[M]_x \\Rightarrow R_0 with R_0 \\approx \\subseq [M']_x$$\n\nby i.h.\n\n$$[x \\leftarrow M \\leftarrow \\overline{\\text{\\Psi}}; Q] \\Rightarrow (\\nu x)(R_0 | \\overline{\\pi}(a_0).([a_0 \\leftrightarrow y_0] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid [\\overline{Q}] \\cdots)))$$\n\nby reduction semantics\n\n$$\\approx \\subseq [x \\leftarrow M \\leftarrow \\overline{\\text{\\Psi}}; Q] = (\\nu x)([M]_x | \\overline{\\pi}(a_0).([a_0 \\leftrightarrow y_0] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid [\\overline{Q}] \\cdots)))$$\n\nby congruence\n\nCase: $x \\leftarrow \\{x \\leftarrow P_0 \\leftarrow \\overline{\\text{\\Psi}}_1\\} \\leftarrow \\overline{\\text{\\Psi}}; Q \\rightarrow (\\nu x)(P_0(\\overline{\\text{\\Psi}}/\\overline{\\text{\\Psi}}_1) \\mid Q)$\n\n$$[x \\leftarrow \\{x \\leftarrow P_0 \\leftarrow \\overline{\\text{\\Psi}}_1\\} \\leftarrow \\overline{\\text{\\Psi}}; Q] =$$\n\n$$(\\nu x)(x(w_0) \\cdots .x(w_n).[P_0]_x | \\overline{\\pi}(a_0).([a_0 \\leftrightarrow y_0] \\mid \\cdots \\mid x(a_n).([a_n \\leftrightarrow y_n] \\mid [\\overline{Q}] \\cdots)))$$\n\nby definition\n\n$$\\rightarrow^+ (\\nu x)([P_0]_x | [\\overline{Q}])$$\n\nby reduction semantics\n\n$$\\approx \\subseq (\\nu x)([P_0]_x | [\\overline{Q}])$$\n\nby reduction semantics\n\nTheorem A.28 (Operational Soundness).\n\n1. If $\\Psi; \\Gamma; \\Delta \\vdash P :: z:A$ and $\\langle P \\rangle \\rightarrow M$ then $P \\Rightarrow^* Q$ such that $M =_\\alpha \\langle Q \\rangle$\n2. If $\\Psi \\vdash M : \\tau and \\langle M \\rangle \\rightarrow N$ then $M \\rightarrow^+ M'$ such that $N =_\\alpha \\langle M' \\rangle$\n\nProof. By induction on the given reduction.\n\nCase: $\\langle P_0 \\rangle\\{(\\langle M \\rangle \\overline{\\text{\\Psi}})/x\\} \\rightarrow N\\{(\\langle M \\rangle \\overline{\\text{\\Psi}})/x\\}$\n\n$$P = x \\leftarrow \\{x \\leftarrow P_2 \\leftarrow \\overline{\\text{\\Psi}}\\} \\leftarrow \\overline{\\text{\\Psi}}; P_0 with N =_\\alpha \\langle R \\rangle$$\n\nby inversion\n\n$$P \\Rightarrow^* x \\leftarrow M \\leftarrow \\overline{\\text{\\Psi}}; R$$\n\nby definition of $\\Rightarrow$\n\n$$\\langle x \\leftarrow M \\leftarrow \\overline{\\text{\\Psi}}; R \\rangle = \\langle R \\rangle\\{(\\langle M \\rangle \\overline{\\text{\\Psi}})/x\\}$$\n\nby definition\n\n$$=_\\alpha N\\{(\\langle M \\rangle \\overline{\\text{\\Psi}})/x\\}$$\n\nby congruence\n\nCase: $\\langle P_0 \\rangle\\{(\\langle M \\rangle \\overline{\\text{\\Psi}})/x\\} \\rightarrow \\langle P_0 \\rangle\\{M'/x\\}$\nIf \\( \\text{Theorem A.28 (Operational Completeness).} \\)\n\n1. If \\( \\Psi; \\Gamma; \\Delta \\vdash P :: z: A \\) and \\( P \\rightarrow Q \\) then \\( \\llbracket P \\rrbracket \\rightarrow^*_\\beta \\llbracket Q \\rrbracket \\)\n\n2. If \\( \\Psi \\vdash M : \\tau \\) and \\( M \\rightarrow N \\) then \\( \\llbracket M \\rrbracket \\rightarrow^* \\llbracket N \\rrbracket \\)\n\n**Proof.** By induction on the given reduction\n\n**Case:** \\((x \\leftarrow M \\leftarrow \\overline{y}_i; P_0) \\rightarrow (x \\leftarrow M' \\leftarrow \\overline{y}_i; P_0)\\) with \\( M \\rightarrow M' \\)\n\n\\[\n\\begin{align*}\n\\llbracket x \\leftarrow M \\leftarrow \\overline{y}_i; P_0 \\rrbracket &= \\llbracket (\\llbracket M \\rrbracket \\overline{y}_i/x) \\rrbracket \\\\\n\\llbracket M \\rrbracket \\rightarrow^* \\llbracket M' \\rrbracket & \\quad \\text{by definition} \\\\\n\\llbracket x \\leftarrow M' \\leftarrow \\overline{y}_i; P_0 \\rrbracket &= \\llbracket (\\llbracket M' \\rrbracket \\overline{y}_i/x) \\rrbracket \\\\\n\\llbracket P_0 \\rrbracket \\{\\llbracket M \\rrbracket \\overline{y}_i/x\\} &\\rightarrow^*_\\beta \\llbracket P_0 \\rrbracket \\{\\llbracket M' \\rrbracket \\overline{y}_i/x\\} \\quad \\text{by congruence}\n\\end{align*}\n\\]\n\n**Case:** \\((x \\leftarrow \\{x \\leftarrow Q \\leftarrow \\overline{y}_i\\} \\leftarrow \\overline{y}_i; P_0) \\rightarrow (\\nu x)(Q \\mid P_0)\\)\n\n\\[\n\\begin{align*}\n\\llbracket x \\leftarrow \\{x \\leftarrow Q \\leftarrow \\overline{y}_i\\} \\leftarrow \\overline{y}_i; P_0 \\rrbracket &= \\llbracket (\\llbracket Q \\rrbracket/x) \\rrbracket \\\\\n\\rightarrow^*_\\beta \\llbracket P_0 \\rrbracket \\{\\llbracket Q \\rrbracket/x\\} & \\quad \\text{by congruence and transitivity} \\\\\n\\llbracket (\\nu x)(Q \\mid P_0) \\rrbracket &= \\llbracket (\\llbracket Q \\rrbracket/x) \\rrbracket \\quad \\text{by definition}\n\\end{align*}\n\\]\n\n**Theorem A.29 (Inverse Encodings – Processes).** If \\( \\Psi; \\Gamma; \\Delta \\vdash P :: z: A \\) then \\( \\llbracket \\llbracket P \\rrbracket \\rrbracket_z \\approx_L \\llbracket P \\rrbracket \\). Also, if \\( \\Psi \\vdash M : \\tau \\) then \\( \\llbracket \\llbracket M \\rrbracket_z \\rrbracket =_\\beta \\llbracket M \\rrbracket \\).\n\nWe prove each case as a separate theorem.\n\n**Theorem A.29 (Inverse Encodings – Processes).** If \\( \\Psi; \\Gamma; \\Delta \\vdash P :: z: A \\) then \\( \\llbracket \\llbracket P \\rrbracket \\rrbracket_z \\approx_L \\llbracket P \\rrbracket \\)\n\n**Proof.** By induction on the given typing derivation. We show the new cases.\n\n**Case:** Rule \\( \\{\\} E \\)\n\\[ P = x \\leftarrow M \\leftarrow \\gamma; Q \\] by inversion\n\\[ \\langle P \\rangle = \\langle Q \\rangle \\{ \\langle (M) \\rangle_x / x \\} \\] by definition\n\\[ \\llbracket (Q) \\{ \\langle (M) \\rangle_x / x \\} \\rrbracket_z = (\\nu a)(\\llbracket (M) \\gamma \\rrbracket_a | \\llbracket (Q) \\rrbracket_z \\{ a / x \\}) \\] by Lemma A.9\n\\[ = (\\nu a, x)(\\llbracket (M) \\rrbracket_x | \\pi(a_0).((a_0 \\leftrightarrow y_0) | \\cdots | x(a_n).((a_n \\leftrightarrow y_n) | \\llbracket (Q) \\rrbracket_x \\{ a / x \\})\\cdots)) \\) by definition\n\\[ \\equiv (\\nu x)(\\llbracket (M) \\rrbracket_x | \\pi(a_0).((a_0 \\leftrightarrow y_0) | \\cdots | x(a_n).((a_n \\leftrightarrow y_n) | \\llbracket (Q) \\rrbracket_x \\{ a / x \\})\\cdots)) \\) by definition\n\\[ \\approx_L (\\nu x)(\\llbracket (M) \\rrbracket_x | \\pi(a_0).((a_0 \\leftrightarrow y_0) | \\cdots | x(a_n).((a_n \\leftrightarrow y_n) | \\llbracket (Q) \\rrbracket_x \\{ a / x \\})\\cdots)) \\) by i.h.\n\n**Theorem A.30 (Inverse Encodings – λ-terms).** If \\( \\Psi \\vdash M : \\tau \\) then \\( \\langle \\llbracket (M) \\rrbracket_z \\rangle_\\beta = \\beta \\langle M \\rangle \\)\n\n**Proof.** By induction on the given typing derivation. We show the new cases.\n\n**Case:** Rule \\( \\{ \\} I \\)\n\n\\[ M = \\{ x \\leftarrow P \\leftarrow \\gamma \\} \\] by inversion\n\\[ \\llbracket M \\rrbracket_z = z(y_0).\\ldots.z(y_n).\\llbracket P \\{ z / x \\} \\rrbracket \\] by definition\n\\[ \\llbracket z(y_0).\\ldots.z(y_n).\\llbracket P \\{ z / x \\} \\rrbracket \\rrbracket \\equiv \\lambda y_0.\\ldots.\\lambda y_n.\\llbracket P \\rrbracket_z \\] by definition\n\\[ \\llbracket M \\rrbracket = \\lambda y_0.\\ldots.\\lambda y_n.\\llbracket P \\rrbracket \\] by definition\n\\[ \\approx_\\beta \\lambda y_0.\\ldots.\\lambda y_n.\\llbracket P \\rrbracket \\] by i.h.\n\n### A.12 Strong Normalisation for Higher-Order Sessions\n\nWe modify the encoding from processes to λ-terms by considering the encoding of derivations ending with the copy rule as follows (we write \\( \\langle \\cdot \\rangle^+ \\) for this revised encoding):\n\n\\[ \\langle (\\nu x)u(x).P \\rangle^+ \\equiv \\text{let } 1 = () \\text{ in } \\langle P \\rangle^+ \\{ u / x \\} \\]\n\nAll other cases are as before. It is immediate that the revised encoding preserves typing. We now revisit operational completeness as:\n\n**Lemma A.31 (Operational Completeness).** If \\( \\Psi ; \\Gamma ; \\Delta \\vdash P :: z: \\mathsf{A} \\) and \\( P \\rightarrow Q \\) then \\( \\langle P \\rangle^+ \\rightarrow_\\beta^* \\langle Q \\rangle^+ \\)\n\n**Proof.**\n\n**Case:** \\( (\\nu u)(\\text{!}u(x).P_0 \\mid \\pi(x).P_1) \\rightarrow (\\nu u)(\\text{!}u(x).P_0 \\mid (\\nu x)(P_0 \\mid P_1)) \\)\n\n\\[ \\langle (\\nu u)(\\text{!}u(x).P_0 \\mid \\pi(x).P_1) \\rangle^+ = \\text{let } 1 = () \\text{ in } \\langle P_0 \\rangle^+ \\{ u / x \\} \\{ P_0 \\}^+ / u \\] by definition\n\\[ \\rightarrow \\langle P_0 \\rangle^+ \\{ (P_0)^+ / x \\} \\{ (P_0)^+ / u \\} \\] by operational semantics\n\\[ \\langle (\\nu u)(\\text{!}u(x).P_0 \\mid (\\nu x)(P_0 \\mid P_1)) \\rangle^+ = \\langle P_0 \\rangle^+ \\{ (P_0)^+ / x \\} \\{ (P_0)^+ / u \\} \\] by definition\n\nOther cases are unchanged.\n\nWe remark that with this revised encoding, operational soundness becomes:\n\n**Lemma A.32.** If \\( \\Psi ; \\Gamma ; \\Delta \\vdash P :: z: \\mathsf{A} \\) and \\( \\langle P \\rangle^+ \\rightarrow M \\) then \\( P \\rightarrow^* Q \\) such that \\( \\langle Q \\rangle \\rightarrow^* M \\).\nProof.\n\nCase: $\\langle P \\rangle^+ = \\text{let } 1 = \\langle \\rangle \\text{ in } \\langle P_0 \\rangle^+ \\{u/x\\}$ with $\\langle P \\rangle^+ \\to \\langle P_0 \\rangle^+ \\{u/x\\}$\n\n$\\langle P \\rangle^+ = \\text{let } 1 = \\langle \\rangle \\text{ in } \\langle P_0 \\rangle^+ \\{u/x\\}$ by operational semantics, as needed.\n\nRemaining cases are fundamentally unchanged.\n\nThe revised encoding remains mutually inverse with the $\\llbracket \\cdot \\rrbracket_z$ encoding. We show only the relevant new cases.\n\n**Lemma A.33.** If $\\Psi; \\Gamma; \\Delta \\vdash P :: z : A$ then $\\llbracket \\langle P \\rangle^+ \\rrbracket_z \\approx_L \\llbracket P \\rrbracket$\n\nProof.\n\nCase: copy rule\n\n$\\llbracket \\langle P \\rangle^+ \\rrbracket_z = \\text{let } 1 = \\langle \\rangle \\text{ in } \\langle P_0 \\rangle^+ \\{u/x\\}$ by definition\n\n$\\llbracket \\langle P \\rangle^+ \\rrbracket_z = \\text{let } 1 = \\langle \\rangle \\text{ in } \\langle P_0 \\rangle^+ \\{u/x\\}$ by definition\n\n$\\approx \\llbracket \\nu x \\langle u \\rangle \\cdot \\{x \\leftrightarrow z\\} \\rrbracket$ by structural congruence\n\n$\\approx \\llbracket P \\rrbracket$ by compositionality\n\n$\\approx L \\llbracket P \\rrbracket$ by i.h. + congruence + definition of $\\approx$ for open processes\n\n**Lemma A.34.** If $\\Psi \\vdash M : \\tau$ then $\\llbracket \\langle M \\rangle \\rrbracket_z^+ = \\beta \\llbracket M \\rrbracket^+$\n\nProof.\n\nCase: uvar rule\n\n$\\llbracket u \\rrbracket_z = \\langle \\nu x \\rangle \\langle u \\rangle \\cdot \\{x \\leftrightarrow z\\}$ by definition\n\n$\\llbracket \\langle \\nu x \\rangle \\langle u \\rangle \\cdot \\{x \\leftrightarrow z\\} \\rrbracket^+ = \\text{let } 1 = \\langle \\rangle \\in u = \\beta u$\n\n**Theorem 4.9 (Strong Normalisation).** Let $\\Psi; \\Gamma; \\Delta \\vdash P :: z : A$. There is no infinite reduction sequence starting from $P$.\n\nProof. The result follows from the operational completeness result above (Lemma A.31), which requires every process reduction to be matched with one or more reductions in the $\\lambda$-calculus. We can thus prove our result via strong normalisation of $\\rightarrow_{\\beta}$: Assume an infinite reduction sequence $P \\rightarrow P' \\rightarrow P'' \\rightarrow \\ldots$, by completeness this implies that there must exist an infinite sequence $\\langle P \\rangle \\rightarrow_{\\beta}^+ \\langle P' \\rangle \\rightarrow_{\\beta}^+ \\langle P'' \\rangle \\rightarrow_{\\beta}^+ \\ldots$, deriving a contradiction.\nFig. 5. Translation on Typing Derivations from Poly$_\\forall$ to Linear-F (Part 1)\nFig. 6. Translation on Typing Derivations from Polyπ to Linear-F (Part 2)"}}},{"rowIdx":90,"cells":{"id":{"kind":"string","value":"6d33d35d540b297218287adde2d6284b2cbc42eb"},"text":{"kind":"string","value":"Continuous Integration, Deployment and Testing in DevOps Environment\n\nAnand Srivatsav Amaradri\nSwetha Bindu Nutralapati\n\nFaculty of Computing\nBlekinge Institute of Technology\nSE–371 79 Karlskrona, Sweden\nThis thesis is submitted to the Faculty of Computing at Blekinge Institute of Technology in partial fulfillment of the requirements for the degree of Master of Science in Software Engineering. The thesis is equivalent to 20 weeks of full time studies.\n\nContact Information:\nAuthor(s):\nAnand Srivatsav Amaradri\nE-mail: anam15@student.bth.se\n\nSwetha Bindu Nutalapati\nE-mail: swnu15@student.bth.se\n\nUniversity advisor:\nAhmad Nauman Ghazi\nDepartment of Software Engineering\n\nFaculty of Computing\nBlekinge Institute of Technology\nSE–371 79 Karlskrona, Sweden\n\nInternet : www.bth.se\nPhone : +46 455 38 50 00\nFax : +46 455 38 50 57\nAbstract\n\n**Context.** Owing to a multitude of factors like rapid changes in technology, market needs, and business competitiveness, software companies these days are facing pressure to deliver software rapidly and on a frequent basis. For frequent and faster delivery, companies should be lean and agile in all phases of the software development life cycle. An approach called DevOps, which is based on agile principles has come into play. DevOps bridges the gap between development and operations teams and facilitates faster product delivery. The DevOps phenomenon has gained a wide popularity in the past few years, and several companies are adopting DevOps to leverage its perceived benefits. However, the organizations may face several challenges while adopting DevOps. There is a need to obtain a clear understanding of how DevOps functions in an organization.\n\n**Objectives.** The main aim of this study is to provide a clear understanding about how DevOps works in an organization to researchers and software practitioners. The objectives of the study are to identify the benefits of implementing DevOps in organizations where agile development is in practice, the challenges faced by organizations during DevOps adoption, to identify the solutions/ mitigation strategies to overcome the challenges, the DevOps practices, and the problems faced by DevOps teams during continuous integration, deployment and testing.\n\n**Methods.** A mixed methods approach having both qualitative and quantitative research methods is used to accomplish the research objectives. A Systematic Literature Review is conducted to identify the benefits and challenges of DevOps adoption, and the DevOps practices. Interviews are conducted to further validate the SLR findings, and identify the solutions to overcome DevOps adoption challenges, and the DevOps practices. The SLR and interview results are mapped, and a survey questionnaire is designed. The survey is conducted to validate the qualitative data, and to identify the other benefits and challenges of DevOps adoption, solutions to overcome the challenges, DevOps practices, and the problems faced by DevOps teams during continuous integration, deployment and testing.\nResults. 31 primary studies relevant to the research are identified for conducting the SLR. After analysing the primary studies, an initial list of the benefits and challenges of DevOps adoption, and the DevOps practices is obtained. Based on the SLR findings, a semi-structured interview questionnaire is designed, and interviews are conducted. The interview data is thematically coded, and a list of the benefits, challenges of DevOps adoption and solutions to overcome them, DevOps practices, and problems faced by DevOps teams is obtained. The survey responses are statistically analysed, and a final list of the benefits of adopting DevOps, the adoption challenges and solutions to overcome them, DevOps practices and problems faced by DevOps teams is obtained.\n\nConclusions. Using the mixed methods approach, a final list of the benefits of adopting DevOps, DevOps adoption challenges, solutions to overcome the challenges, practices of DevOps, and the problems faced by DevOps teams during continuous integration, deployment and testing is obtained. The list is clearly elucidated in the document. The final list can aid researchers and software practitioners in obtaining a better understanding regarding the functioning and adoption of DevOps. Also, it has been observed that there is a need for more empirical research in this domain.\n\nKeywords: DevOps, software development, development, operations, benefits, challenges, principles, practices.\nAcknowledgments\n\nWe would like to thank our supervisor Mr. Ahmad Nauman Ghazi for his invaluable support, patience and guidance throughout our thesis. Without his help and motivation, we would not have completed our thesis. We would like to thank our families for supporting us throughout our journey. Our heartfelt thanks to all the practitioners who have taken the time to help us out.\n# Contents\n\nAbstract\n\nAcknowledgments\n\nList of Figures\n\nList of Tables\n\n1 Introduction\n\n1.1 Introduction\n\n1.2 Related Work\n\n1.3 Aim and Objectives\n\n1.4 Research Contributions\n\n1.5 Overview of the thesis\n\n2 Research Method\n\n2.1 Research Questions\n\n2.2 Research Method\n\n2.3 Rationale for choosing mixed methods approach\n\n2.4 Qualitative Research Methods: SLR and Interviews\n\n2.4.1 Systematic Literature Review\n\n2.4.2 Interviews\n\n2.5 Quantitative Research Method: Survey\n\n3 Systematic Literature Review\n\n3.1 Overview of the SLR Process\n\n3.2 Search Strategy\n\n3.3 Inclusion/Exclusion Criteria\n\n3.3.1 Inclusion Criteria\n\n3.3.2 Exclusion Criteria\n\n3.4 Quality Assessment Criteria\n\n3.5 Snowballing\n\n3.6 Data Extraction and Synthesis\n\n3.7 SLR Results\n3.7.1 Analysis of Literature Regarding the Benefits of Adopting DevOps in Organizations ........................................... 25\n3.7.2 Analysis of Literature Regarding the Challenges of Adopting DevOps in Organizations ........................................... 27\n3.7.3 Analysis of Literature Regarding the Practices of DevOps ................................................................. 30\n3.8 Discussion and Conclusion ................................................................. 32\n3.9 Threats to Validity ................................................................. 34\n\n4 Analysis of Interview Data ................................................................. 36\n4.1 Demographics of Interviewees ................................................................. 37\n4.2 Codes and Themes for RQ1 ................................................................. 38\n 4.2.1 Analysis of Interview Responses for RQ1 ................................................................. 38\n4.3 Codes and Themes for RQ2 ................................................................. 40\n 4.3.1 Analysis of Interview Responses for RQ2 ................................................................. 40\n4.4 Codes and Themes for RQ3 ................................................................. 44\n 4.4.1 Analysis of Interview Responses for RQ3 ................................................................. 44\n4.5 Codes and Themes for RQ4 ................................................................. 47\n 4.5.1 Analysis of Interview Responses for RQ4 ................................................................. 47\n4.6 Codes and Themes for RQ5 ................................................................. 51\n 4.6.1 Analysis of Interview Responses for RQ5 ................................................................. 52\n4.7 Discussion ................................................................. 54\n4.8 Threats to Validity ................................................................. 58\n\n5 Analysis of Survey Questionnaire Results ................................................................. 61\n5.1 Target Population and Sampling ................................................................. 61\n5.2 Designing the Survey Questionnaire ................................................................. 62\n5.3 Survey Questionnaire Validation ................................................................. 63\n5.4 Results of the Survey ................................................................. 64\n 5.4.1 Analysis of the Demographics of the Respondents ................................................................. 64\n5.4.2 Benefits of Implementing DevOps in Organizations ................................................................. 68\n5.4.3 Challenges faced by Organizations while adopting DevOps ................................................................. 69\n5.4.4 Solutions to overcome the Challenges faced during DevOps adoption ................................................................. 71\n5.4.5 Practices to be included by organizations for adopting DevOps ................................................................. 72\n5.4.6 Problems faced by DevOps Teams during Continuous Integration, Deployment and Testing ................................................................. 73\n5.4.7 Results of the Open-ended Questions ................................................................. 74\n5.5 Threats to Validity ................................................................. 78\n\n6 Discussion ................................................................. 80\n6.1 Answering the RQs ................................................................. 80\nList of Figures\n\n2.1 The mixed methods approach design ........................................ 14\n3.1 The SLR process ................................................................. 18\n3.2 Selection of Primary Studies ................................................. 23\n3.3 Year wise Distribution of Primary Studies ............................... 24\n5.1 Geographical Location of Respondents ................................. 64\n5.2 Size of Organizations of Respondents ................................ 66\n5.3 Work Experience of Respondents ....................................... 66\n5.4 Experience with DevOps ..................................................... 67\n5.5 Methodology followed before DevOps ................................. 67\n5.6 Benefits of adopting DevOps .............................................. 69\n5.7 DevOps adoption Challenges ............................................. 70\n5.8 Solutions to overcome the DevOps adoption Challenges .......... 72\n5.9 DevOps practices ............................................................... 73\n5.10 Problems faced by DevOps teams during CI, CD and CT ......... 74\nList of Tables\n\n<table>\n<thead>\n<tr>\n<th>Table</th>\n<th>Description</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>3.1</td>\n<td>Search Strings</td>\n<td>20</td>\n</tr>\n<tr>\n<td>3.2</td>\n<td>Data Extraction Form</td>\n<td>24</td>\n</tr>\n<tr>\n<td>4.1</td>\n<td>Demographics of Interviewees</td>\n<td>37</td>\n</tr>\n<tr>\n<td>4.2</td>\n<td>Codes and Themes for RQ1</td>\n<td>38</td>\n</tr>\n<tr>\n<td>4.3</td>\n<td>Codes and Themes for RQ2</td>\n<td>41</td>\n</tr>\n<tr>\n<td>4.4</td>\n<td>Codes and Themes for RQ3</td>\n<td>45</td>\n</tr>\n<tr>\n<td>4.5</td>\n<td>Codes and Themes for RQ4</td>\n<td>47</td>\n</tr>\n<tr>\n<td>4.6</td>\n<td>Codes and Themes for RQ5</td>\n<td>52</td>\n</tr>\n<tr>\n<td>4.7</td>\n<td>Benefits identified from SLR and Interviews</td>\n<td>55</td>\n</tr>\n<tr>\n<td>4.8</td>\n<td>Challenges identified from SLR and Interviews</td>\n<td>56</td>\n</tr>\n<tr>\n<td>4.9</td>\n<td>Solutions identified from Interviews</td>\n<td>57</td>\n</tr>\n<tr>\n<td>4.10</td>\n<td>Practices identified from SLR and Interviews</td>\n<td>58</td>\n</tr>\n<tr>\n<td>4.11</td>\n<td>Problems identified from the Interviews</td>\n<td>59</td>\n</tr>\n<tr>\n<td>5.1</td>\n<td>Roles of the Respondents</td>\n<td>65</td>\n</tr>\n<tr>\n<td>6.1</td>\n<td>Final List of Benefits</td>\n<td>81</td>\n</tr>\n<tr>\n<td>6.2</td>\n<td>Final List of Challenges</td>\n<td>83</td>\n</tr>\n<tr>\n<td>6.3</td>\n<td>Final List of Solutions</td>\n<td>84</td>\n</tr>\n<tr>\n<td>6.4</td>\n<td>Final List of Practices</td>\n<td>84</td>\n</tr>\n<tr>\n<td>6.5</td>\n<td>Final List of Problems</td>\n<td>85</td>\n</tr>\n</tbody>\n</table>\nChapter 1\n\n1.1 Introduction\n\nA multitude of factors like increasing business competitiveness, rapid changes in technology and market needs have changed the environment in which software companies operate [14] [47]. Many enterprises as a result face a common challenge: faster and frequent software delivery [53]. Those times when a customer waited for months for a product to release, and then provided feedback have passed. Customers expect fast responses to their ever-changing requirements. Frequent releases are essential for the customer to provide continuous feedback [53]. Companies like Facebook are deploying software to customers on a regular basis [29]. While continuously delivering software to customers offers a business advantage over other rival companies, it is not easy to do it because some challenges, technical and non-technical have to be overcome first [29]. The companies must be lean and agile throughout the entire software development lifecycle in order to overcome these challenges [47].\n\nAgile software development is popular in several enterprises because of its plethora of benefits like reduced development time, increased project success rate, reduced development cost and increased customer satisfaction. Agile development increases the responsiveness and the stakeholders’ needs will be met on time. Agile methods facilitate the collaboration among the development teams [34]. A few examples of agile methodologies include Scrum, XP, Kanban, DSDM, Lean, Crystal etc. [23]. The various agile methodologies are based on iterative and incremental development, and they increase communication between the development team and the stakeholders [34].\n\nHowever, the main focus in agile methodologies has been only on the development side, ignoring the operations side [29]. The operations teams deploy, manage and support systems’ performance at the customers’ site [29]. Owing to this, the development teams deliver builds much faster and the operations teams cannot keep up with the pace, and they will lag behind. This may cause the entire delivery to be delayed [47]. As the development and IT operations are separate organizational units, there is a high possibility of misunderstandings and conflict [49]. According to some software practitioners, this gap between the development and operations teams has a negative effect [13].\n\nTo bridge this gap and increase the communication, collaboration and integration between the developers and operations personnel, a new approach called DevOps has\nChapter 1. Introduction\n\ncome into play [49]. “Dev”+”Ops”=”DevOps” [14]. While the agile methodologies improved the development teams’ performance through collaboration, DevOps extends the collaboration of development towards operations [29]. DevOps is based on agile principles, and it encourages faster development and deployment cycles [34]. DevOps is a loosely defined set of practices intended to make the developers and operations personnel to work together. The overall objective behind DevOps is to maximize the return of investment and increase the customer satisfaction by continuously providing features and increased service quality [14]. Several companies like Facebook, Yahoo, Netflix, Flickr and Fotopedia are implementing DevOps [29] [3] [13] [15].\n\nSo, how do we define DevOps? DevOps is a vague term which has different meanings in different contexts [37]. It is often defined as a combination of development and operations [3] [37]. Dyck et al. [10] have defined DevOps as an \"organizational approach that stresses empathy and cross-functional collaboration within and between teams - especially development and IT operations - in software development organizations, in order to operate resilient systems and accelerate delivery of changes.” According to Roche [38], there is no standard definition for DevOps. There is much debate surrounding on what DevOps really means. He states that some blog posts have summarized DevOps as a specific job which needs the skills of both development and operations, while some others argue that there is no such thing. They believe that DevOps is a new criteria for development, testing, support etc. He points out that many companies take the former view, given that there are several job listings that seek for “DevOps Engineers” [38]. Erich et al. [13] have defined DevOps as a “conceptual framework for supporting development and operations.” From the literature, we have understood DevOps as a framework of principles and practices that organizations can include in their development process.\n\nPeuraneimi [37] refers to DevOps as “agile on steroids.” DevOps includes several principles from the agile methodologies and also some Lean principles. It is a way of managing the software development lifecycle [37]. DevOps is not limited to just development and operations teams [10]. Various stakeholders including business analysts, developers, testers, quality assurance personnel and operations personnel (system, database and network administrators, webmasters and security officers) are involved in DevOps [3]. DevOps covers all the aspects that aid in the delivery of fast, optimized and high quality software [47]. There are four main aspects of DevOps: Culture, Automation, Measurement and Sharing [20]. The main focus on DevOps is on enabling communication and collaboration between teams, not on the standards or tools in an organization [19]. DevOps is facilitated by cloud computing [3]. Usually, it is involved in cloud based services like Infrastructure as a Service (IaaS), Platform as a Service (PaaS) and Software as a Service (SaaS) [37]. Tools which are used to support DevOps include Puppet, Chef, Bladelogic, Salt, Amazon WorkOps, Docker, Vagrant etc. [37] [20] [3].\nChapter 1. Introduction\n\nLet us take a look at the main aspects of DevOps: Culture, Automation, Measurement and Sharing [20].\n\n- **Culture** implies “people over processes and tools” [37]. It means that operations must take part in development and deployment [20]. Operations representatives must attend retrospectives and meetings of the development teams. Similarly, development representatives must have frequent meetings with the operations teams.\n\n- **Automation** the build, deployment and testing processes is essential for obtaining rapid feedback and achieving low lead times. A deployment pipeline is used for automating the processes. If any changes are made in the system, each change will be validated by passing it through a series of automated tests in the pipeline. If the changes are successful, they will be ready for deployment to the testing, staging and production environments [20].\n\n- **Measurement** involves monitoring of both high-level and low-level business metrics. High-level metrics include revenue, transactions per unit time. At low-level, people are measured. To ensure the behavior of people is not influenced by measurement, key performance indicators must be carefully chosen. The metrics should be made visible to everyone involved in the software delivery so that they can see how they are performing [20].\n\n- **Sharing** includes sharing of knowledge, sharing of development tools and sharing of techniques for managing environments and infrastructure by the development and operations teams. A good practice is for the two teams to celebrate together when a release is successful [20].\n\nLwakatare et al. [29] have identified another aspect of DevOps: Monitoring. Operations teams use certain tools and logs to monitor the systems for any issues. Usually the logs can be very large and identifying the issues can be a tedious task for the development and operations teams. Also, no details about the issues will be visible to the teams because of the system design. DevOps ensures that the two teams collaborate to design systems in such a way that details will be displayed. Thus, monitoring will be more effective [29].\n\nPeuraniemi [37] identified Infrastructure as Code (IaC) as the main principle of DevOps. IaC means automatically managing the configurations. Using IaC, environments can be configured faster and infrastructural changes can be made more easily. Subsequently, faster deliveries can be made to the customer. He also identified four principles of collaboration: Respect for one another, Commitment to shared goals, Collective ownership and Shared values [37]. All team members should respect the values of each other and interact well. Everyone should be committed to the shared goals and work towards the success of the project. Collective ownership can ensure that quality of the developed software is increased by using optimal solutions for development. Shared values guarantee customer satisfaction by giving more importance\nto working system and rapid delivery, rather than formal plans [37]. Fietelson et al. state that a culture of personal responsibility is important and methodologies and tools alone are not adequate, as they can always be exploited [15].\n\nVirmani [47] states that DevOps aims to address various problems related to software projects, such as adaptability to change, increasing quality, cost reduction and speed to market. Farroha et al. [14] claim that the main focus of DevOps is on: Continuous and high-quality software delivery, agility and simplicity in technology, processes and human factors, breaking down the barriers through collaboration between development and operations teams. The DevOps principles can be applied to any type of projects, including complex projects, small projects and mobile application projects [47]. Various factors like the type of project involved, organizational needs and capabilities and return on investment (ROI) will determine which principles an organization needs to adopt. The organization will decide how and using what tools and technologies it adopts a principle or a practice of DevOps [47].\n\nThe practices or the enabling techniques of DevOps are: Continuous planning, Continuous integration, Continuous testing, Continuous delivery, Continuous monitoring and Continuous feedback [42] [49] [47] [17]. These practices are known to facilitate rapid delivery of software to the customers [47]. Continuous planning makes it easier for the teams to adapt to the fast changes in business environments by having a prioritized product backlog in hand and a channel that enables continuous feedback from customers. Changes can be made to the backlog any time, based on the feedback obtained [47]. Continuous integration involves an automated process where code compilation and sanity tests will be carried out and deployment packages will be built, as soon as a developer makes a change to the code [47] [17]. Continuous deployment involves automated and continuous deployment of valid software builds to a repository, rather than to the users [17]. Continuous testing involves automation of all test cases in such a way that no user intervention is required, and errors in the builds will be detected faster [47] [17]. Continuous delivery is the practice of continuously deploying software, while ensuring that it is always ready to be released and deployed to the customers [17]. Continuous monitoring enables monitoring of quality parameters throughout the software development, thereby facilitating easier detection and solving of problems [47]. Continuous feedback is facilitated by continuous monitoring of both infrastructure and user behavior. The data related to infrastructure performance and user behavior when interacting with the service will be obtained by continuous monitoring. This data will be used as input to the planning and development processes for improving the service [42].\n\nVirmani [47] notes that different teams in a single organization might need to use different tools to adopt the DevOps practices. According to McCarthy et al. [30] a change in the mindset of everyone involved is crucial to successfully implement DevOps in an organization. It is important that everyone shares the responsibility for both success\nand failure of products [30]. Smeds et al. [42] state that adopting DevOps in an organization is not an easy task, and each organization has a unique way of making the adoption process successful. Virmani [47] stresses that it might not be practical for an organization to move to a full-DevOps state from a non-DevOps state in a brief period of time. He states that organizations should analyse the current workflows and target those areas which have a scope for optimization [47]. The related work is discussed in the next section.\n\n1.2 Related Work\n\nFarroha et al. [14] proposed a framework for ensuring that the overall enterprise performance and security are not compromised while adopting DevOps, as it was observed that DevOps lacks the discipline that engineers are normally used to. Stillwell and Coutinho [45] describe a DevOps approach that was used for integration of software components in a European research project. They have found that the DevOps workflow has caused the development teams to be more open to changes and operate autonomously, providing more frequent updates. They claim that the approach reduced the communication overhead and increased the delivery speed. They note that it is hard to completely quantify the effects, as they just started collecting metrics [45]. Bang et al. [3] identified the Knowledge, Skills and Abilities (KSA) needed for both developers and operations personnel to support the main aspects of DevOps: Culture, Automation, Measurement and Sharing. Erich et al. [13] conducted a mapping study on the cooperation between development and operations teams in organizations. They found that DevOps improves the performance of both development and operations teams, and also improves the quality assurance performance. They note that more research is needed to quantify these benefits [13]. Roche [38] describes about the adoption of DevOps practices into software quality assurance. He states that extending the collaboration between development and operations teams to quality assurance helps the teams in making better decisions on the product development and releases.\n\nGottesheim [19] identifies the most common issues that occur during software development and describes about enabling performance focused DevOps in organizations. He states that problems like guesswork and finger pointing between teams when faced with issues can be avoided by defining and sharing performance metrics across all teams. Shahin [40] states that DevOps and continuous deployment can prove to be challenging for software architects, as applications should be re-architected for supporting the various DevOps practices. McCarthy et al. [30] proposed a framework to incrementally improve the existing DevOps practices into more collaborative and cohesive ones, and measure the collaboration value. Fitzgerald and Stol [17] identified several continuous activities such as continuous integration, deployment, testing, improvement etc. which are crucial for software development in the present business environment.\nChapter 1. Introduction\n\nSmeds et al. [42] identified some challenges faced by software organizations during DevOps adoption. Olszweska and Walden [34] describe about how formal modelling works in DevOps and how quality can be achieved in formal modelling in DevOps. A new language called DevOpSlang was introduced by Wettinger et al. [53] for implementing DevOps in organizations. Lwakatare et al. [29] have identified the main aspects of DevOps as Collaboration, Automation, Measurement and Monitoring, and also developed a framework to provide an understanding of how DevOps works. Wettinger et al. [51] describe about how diverse application environments can be used for implementing DevOps.\n\nWaller et al. [49] state that benchmarks and monitoring should be included into software development right at the beginning, without waiting until problems occur during release. They claim that automated benchmarks help in earlier detection of issues, thereby prevent them from spreading through the deployment pipeline. Cois et al. [7] proposed a model of automated DevOps for guiding organizations on responsibilities and the DevOps infrastructure. They state that automation improves the communication rate and knowledge transfer. Hussaini [21] proposed a model to identify the common key objectives of both Dev and Ops and improving the collaboration between the development and operations units in an organization.\n\nWahaballa et al. [48] identified a problem called conceptual deficit, which is caused by the collaboration between development and operations teams during software deployment. They proposed a Unified DevOps Model (UDOM) for overcoming this problem. Dyck et al. [10] differentiate between release engineering and DevOps, and provide definitions for both terms. Wettinger et al. [50] proposed a holistic approach for capturing DevOps knowledge into a knowledgebase and managing it. Tessem and Iden [46] stated that poor cooperation between development and operations teams leads to reduced user satisfaction and reduced productivity of both the teams, well before the term DevOps came into light. Erich et al. [12] note that there is no specific way of doing DevOps that all companies can follow. Rather, there are various principles and practices, and the organizations need to include the required principles and practices into their development processes [12]. Mohamed [32] introduced a DevOps maturity model for altering the software development life cycle to adapt with DevOps. Mohamed [31] also proposed a tool called DevOps Maturity Calculator (DOMC) for calculating the DevOps maturity level of organizations. He claims that DOMC enables the organizations to include the DevOps maturity model into their processes, and respond faster to customer requirements.\n\nBass et al. [4] argue that along with communicating with operations teams, developers should also look into several other aspects like standards, organizational process descriptions, studies about types of operations failures, etc. in order to understand the issues associated with operations. Kerzazi and Adams [24] identified the main tasks of release and DevOps engineers across the world by conducting an empirical analysis.\nChapter 1. Introduction\n\nof online job listings. They found that automation or scripting is the most important task. Babar et al. [1] proposed a model that aids organizations to select customized DevOps processes to fit their needs. Virmani [47] describes about DevOps applied to various stages of software delivery life cycle, the things organizations need to consider while adopting DevOps, and the perceived benefits of implementing DevOps in organizations. Jones et al. [22] identified the challenges to DevOps adoption by conducting a case study in a UK based company. Lwakatare et al. [28] identified the challenges to DevOps adoption in the embedded systems domain.\n\nIt has been noted that not much literature is available on DevOps, and most of the studies are of low quality. There are very few studies which provide a concrete understanding about how DevOps works in an organization. Smeds et al. [42] identified the possible challenges than organizations may face while adopting DevOps. However, their study was conducted on only one organization, and in the initial stages of DevOps adoption. They mentioned the need to include more organizations in further research for generalizing the challenges of DevOps adoption in organizations. They state that more research needs to be done on the later stages of adoption. There is a need to provide solutions for overcoming the challenges in DevOps adoption. Further, the DevOps principles and practices are not clearly explained in literature. We try to delve deeper into the functioning of the different principles and practices of DevOps. We try to confirm if any of the perceived benefits of adopting DevOps are actually achieved in organizations which practice agile development. No studies have addressed the challenges that DevOps teams may face during the continuous activities like continuous integration, deployment and testing. We try to investigate the challenges faced by teams during the different continuous activities. We attempt to address this research gap by answering the research questions stated in the next chapter.\n\n1.3 Aim and Objectives\n\nThese days, companies need to deliver the software products continuously in order to allow the customers to utilize their services. To do so, they need to follow a structured software development method. With most of the software companies being attracted to the values and principles of agile, product development using agile project management is increasing. To reach the expectations and needs of the customers, the organizations need to advance their development cycle and reduce the product time to market [47]. However, the organizations face many challenges owing to the time pressure, which affects the software quality. The main reason behind this is due to the gaps in between understanding the needs of customer, the development and testing teams and the operations teams. DevOps, which is a collaboration between the development and operations teams aims to reduce these gaps [7]. This approach acts as a bridge between the development teams and the operations teams. It has been found that DevOps can increase the communication, reliability and trust between the development\nChapter 1. Introduction\n\nand operations teams [33]. By overcoming the barriers between the development and operations teams, organizations can respond quickly to the customer demands and support various changes which help them in yielding better outcomes [51].\n\nThe main aim of this thesis is to learn about how DevOps works in an organization. The focus of the thesis is on identifying how implementation of DevOps helps organizations where agile development is in practice, the DevOps adoption challenges and solutions to overcome them, the different DevOps practices, and the problems that DevOps teams may face during continuous integration, deployment and testing.\n\nThe objectives of this research are as follows:\n\n1) To identify the benefits of implementing DevOps in organizations where agile is in practice.\n2) To identify the challenges faced by organizations while adopting DevOps.\n3) Identifying the strategies/solutions to overcome the DevOps adoption challenges.\n4) Identifying the practices that organizations must include for adopting DevOps.\n5) To identify the problems that are faced by the DevOps teams during continuous integration, deployment and testing.\n\n1.4 Research Contributions\n\nThe contributions of this research are as follows:\n\n- A list of the benefits of implementing DevOps in organizations where agile development is in practice.\n- A list of the challenges faced by organizations in adopting DevOps.\n- A list of strategies/solutions to overcome the challenges of adopting DevOps.\n- A list of practices to be included in an organization to adopt DevOps.\n- A list of the problems faced by the DevOps teams during continuous integration, deployment and testing.\n\n1.5 Overview of the thesis\n\nThe remainder of the thesis is structured as follows:\n\nIn Chapter 2, the research method is discussed. The research questions are mentioned, along with the motivation behind each question. The chosen mixed methods approach is elucidated, and the rationale for choosing the method is specified. The selected qualitative and quantitative research methods (SLR, interviews and survey) are elucidated\nand how the research questions are answered using different methods is explained.\n\nIn Chapter 3, the Systematic Literature Review is discussed. The execution of Systematic Literature Review is explained, and the results of SLR are elucidated. The discussions and conclusion are presented. The possible threats to validity of the SLR results are discussed.\n\nIn Chapter 4, the analysis of interview data is explained. The execution of interviews is explained. The interview results, discussions, and validity threats are presented.\n\nIn Chapter 5, the analysis of survey results is explained. The execution of the online survey is explained, and the results are presented. The possible threats to validity of the survey results are discussed.\n\nIn Chapter 6, the results obtained from SLR, interviews and survey are mapped to answer the research questions.\n\nIn Chapter 7, the conclusions made from the thesis are explained, and the scope for future work is discussed.\nChapter 2\n\nResearch Method\n\n2.1 Research Questions\n\nThe thesis aims to address the research gap by answering the following research questions:\n\nRQ1) How does implementing DevOps in the organizations where agile is in practice help them?\n\n*Motivation:* This research question aims at looking at the benefits of adopting DevOps in organizations where agile is in practice. The perceived benefits have a crucial role in determining whether or not to implement DevOps in an organization. We aim to look at the perceived benefits of adopting DevOps which are listed in literature, and also the actual benefits achieved in practice by organizations.\n\nRQ2) What are the challenges faced by the organizations while adopting DevOps?\n\n*Motivation:* It is very important to identify the challenges to the DevOps adoption process. As this thesis aims at identifying the challenges in the DevOps adoption process, it can contribute to the research pool and also help the organizations by letting them know about the risks involved with adopting DevOps.\n\nRQ3) How to overcome the challenges faced by the organizations in adopting DevOps?\n\n*Motivation:* Identifying the strategies to overcome the challenges inherent with DevOps adoption can effectively guide the organizations whenever they are faced with an impediment. Also, several problems can be avoided in the first place if the organizations know about the challenges in DevOps adoption and their respective mitigation strategies. Thus, there is a need to identify the strategies to overcome the challenges faced by the organizations in adopting DevOps.\n\nRQ4) What are the practices that an organization needs to include while adopting DevOps?\n\n*Motivation:* There is a need to know about what exactly are the practices that an organization needs to include as a part of the DevOps adoption process. There is no proper guidance in existing literature about the practices and principles of DevOps. This research question aims at identifying the practices that an organization needs to include while adopting DevOps.\nRQ5) What are the problems faced by the DevOps teams during continuous integration, deployment and testing?\n\n**Motivation:** DevOps involves continuous integration, deployment and testing [47]. The DevOps teams need to work together to continuously integrate, deploy and test the code. This may prove to be challenging for the DevOps teams. Answering this research question can help to identify the problems that the teams may face during continuous integration, deployment and testing.\n\n## 2.2 Research Method\n\nWe employed a mixed methods approach for our research. Generally, there are three types of research methods: Qualitative, Quantitative and Mixed methods [8]. One major difference between the qualitative and quantitative methods is that qualitative methods use words and open-ended questions, while quantitative methods use numbers and closed-ended questions. The qualitative methods are flexible in nature, and they involve open-ended questions. The data obtained will be either in text or audio-visual format, and is analysed based on themes and patterns [8]. Some examples of qualitative methods are grounded theory analysis, interviews and literature reviews. Quantitative methods are more structured, with closed-ended questions. The data obtained will be numeric, and is statistically analysed. Examples of quantitative methods include experiments and surveys [8].\n\nThe mixed methods approach combines both qualitative and quantitative data. This approach is particularly useful when a researcher wants to generalize his findings to a population and also give a detailed understanding about a concept to the readers. The research can take more time when using this method, because both qualitative and quantitative data needs to be collected and analysed [8]. The motivation behind choosing this approach is that we can get more reliable and valid results than using either a qualitative or quantitative approach alone. The qualitative research methods used in this research are Systematic Literature Review and Skype Interviews. A survey involving an online questionnaire is employed as the quantitative research method. RQ1, RQ2 and RQ4 are answered using SLR. All the research questions, RQ1, RQ2, RQ3, RQ4 and RQ5 are answered using interviews and survey.\n\n## 2.3 Rationale for choosing mixed methods approach\n\nOur research aims at identifying all possible challenges that an organization may face while adopting DevOps, during both the initial and later stages of adoption, and providing solutions to overcome these challenges. We also try to identify the practices which organizations include as a part of DevOps adoption process, the benefits of adopting DevOps which are achieved in practice by organizations, and the problems faced by\nChapter 2. Research Method\n\nDevOps teams during various continuous activities. DevOps is a relatively new concept, and not much literature is available. There are very few good quality studies which provide a concrete understanding of DevOps. There is a need to provide comprehensive and reliable results, and thus we employed the mixed methods approach.\n\nWe follow an exploratory sequential mixed methods design. In this process, we first gather the qualitative data, analyse it and then use the results in the quantitative phase. The purpose of following this process is to validate if the data from a small population sample can be generalized to a larger sample [8]. So, first we conduct a Systematic Literature Review, followed by Interviews. Based on the results of the qualitative methods, we devise the survey questionnaire, which will be used to gather the quantitative data. Because we are using both quantitative and qualitative methods to obtain results, the data will be triangulated. Thus, the research will be validated [41].\n\n2.4 Qualitative Research Methods: SLR and Interviews\n\n2.4.1 Systematic Literature Review\n\nA systematic literature review (SLR) was conducted to identify the perceived benefits of implementing DevOps in organizations, DevOps adoption challenges, and the vari-\nous DevOps principles and practices. The Kitchenham guidelines [25] were followed to conduct the SLR. Kitchenham et al. [25] defined systematic literature review as “a means of identifying, evaluating and interpreting all available research relevant to a particular research question, or topic area, or phenomenon of interest”. SLR is mostly used for summarizing all the existing evidence related to a topic, identifying gaps in current research, and to provide a background for planning the new research activities accordingly. Using SLR, all the existing evidence can be summarized in an unbiased and thorough manner [25]. The steps usually followed when conducting a systematic review are defining the topic, identifying search parameters, finding evidence, analysing evidence and integrating evidence [41]. We followed a review protocol for conducting the SLR, which is explained in detail in the next chapter. The motivation behind choosing SLR as the qualitative research method is to gather reliable and valid data. The SLR findings helped us to identify the perceived benefits of implementing DevOps in organizations, adoption challenges, the principles and practices. The SLR results are also validated by the interviews and survey. In this research, we answer RQ1, RQ2 and RQ4 using SLR.\n\nThere are other alternate qualitative research methods like systematic mapping study and literature review. Systematic mapping study shares some similarities with the systematic review method, but they have different approaches to data analysis. Also, quality assessment is more common in systematic reviews, whereas there is no need to perform it in mapping studies [36]. Mapping studies are more suited for topics that have broad scope [25]. Finally, the results obtained through systematic reviews will be more reliable and valid because the goal is to identify and aggregate all the relevant evidence. Literature reviews are used for summarizing the evidence on a given topic, and the results are often prone to researcher bias. Also, in literature reviews, no quality assessment or data analysis will be done, unlike in systematic reviews [35]. The data obtained from systematic reviews is less prone to bias and can be more reliable [35] [25]. Thus, we employed SLR as the qualitative research method.\n\n2.4.2 Interviews\n\nInterviews are chosen as the second qualitative research method. Generally, in qualitative interviews, face-to-face or telephonic interviews are conducted [8]. At least one researcher talks to at least one respondent in an interview. Interviews can be either structured or semi-structured [41]. Structured interviews are closed-ended; the researcher frames some questions, and asks them exactly as they are with no deviations. The structured interview data is often statistically analysed. Semi-structured interviews are more open-ended. Open-ended questions which facilitate more interaction are asked, and new questions may be framed as new information is gathered. The semi-structured interview data is often analysed using qualitative analysis methods. Semi-structured interviews are more interactive, and we can get some unexpected responses. Also, higher quality responses can be obtained if the interviewer and the\nrespondent have rapport [41].\n\nThe researcher forms an interview protocol for recording the information gathered. Audio recording, video recording or note-taking can be done for recording the information [8]. In our research, we conducted semi-structured interviews, audiotaped and transcribed them. We employed convenience sampling, a non-probabilistic sampling method for selecting the interview respondents. 12 respondents from 11 different software organizations were interviewed using Skype. We were given permission for audio recording by all the respondents. The respondents are software practitioners experienced with DevOps. Most of the interviews lasted for around 45-60 minutes, while two interviews lasted 120 minutes. Thematic analysis was employed as the data analysis method. The steps involved in data analysis are transcribing the data, organizing the data, reading through all the data, coding the data, identifying themes, and interpreting the meaning of themes [8].\n\nAll of the research questions, RQ1, RQ2, RQ3, RQ4 and RQ5 are answered using the interview data. The perceived benefits of adopting DevOps in organizations are identified from the literature. We also ascertain the actual benefits which are achieved in practice by software organizations by interviewing DevOps practitioners. Smeds et al. [42] identified some DevOps adoption impediments by conducting research on one software organization. We aim to identify more challenges, and see if the challenges identified by Smeds et al. [42] can be generalized by including 11 different organizations into our study. We also try to identify the strategies to overcome these challenges by interviewing the practitioners about the measures they use to overcome the adoption challenges. We look into the different DevOps practices that organizations include into their development processes. Also, we identify the challenges that DevOps teams face during continuous integration, deployment and testing from the interviews.\n\n2.5 Quantitative Research Method: Survey\n\nOnline survey is the chosen quantitative research method. The results obtained from the qualitative methods, SLR and interviews were used to design the survey questionnaire. The online survey was conducted to validate if the SLR and interview results could be generalized to a larger population sample, and to identify the aspects not covered in the qualitative data. According to Shull et al. [41] surveys are used to \"identify the characteristics of a broad population of individuals.\"\n\nSurvey is chosen because respondents from all over the world can answer it. The steps followed to conduct the survey are: defining the survey objectives, planning the survey, designing the survey questionnaire, validating the questionnaire, collecting data, and analysing the data [41]. The survey process is thoroughly explained in the later parts of the document. The questionnaire was designed using google docs, and the collected\ndata was statistically analysed. The survey questionnaire was validated by piloting it with three DevOps practitioners. Then it was broadcasted to personal contacts, and practitioners identified using LinkedIn and Facebook. The link to survey was posted in several online groups and forums related to DevOps (e.g. DevOps Professionals, DevOps Matters in LinkedIn). Further, the respondents were requested to forward the questionnaire to their personal contacts who are DevOps practitioners. As the survey is prepared using google forms, the responses are stored directly in an excel spread sheet. The target population is software practitioners that have/are working with DevOps. Convenience sampling was done to select the respondents. 94 respondents were sent the survey personally. 50 complete responses out of 53 were considered for statistical analysis. The three responses were discarded because the two respondents have left a blank (-) in the experience in DevOps field. Another respondent commented 22 years in the experience field. However, DevOps only came into play about six years back. Thus, the responses were not considered. The statistical analysis methods include descriptive statistics and inferential statistics [41]. In our study, descriptive statistics was used to analyse the quantitative data.\n\nCreswell [8] notes that the sample for quantitative phase should be different from the qualitative phase sample, as the purpose of exploratory sequential design is to validate if the data from smaller sample can be generalized to a larger population sample. Hence, it was ensured that the survey respondents are different from the interviewees. The alternative quantitative research methods include case study and experiment. Case studies are costly, and often the results from a particular context cannot be generalized to other contexts [41]. Thus, case study was not chosen. To conduct an experiment, we require a hypothesis, certain parameters and variables, which is not the case for our study [41]. Thus, experiment is not chosen. All the research questions, RQ1, RQ2, RQ3, RQ4 and RQ5 are answered using survey, and conclusions are drawn.\nChapter 3\n\nSystematic Literature Review\n\n3.1 Overview of the SLR Process\n\nThe SLR was conducted by following the guidelines specified by Kitchenham et al. [25]. Initially, a review protocol was developed for conducting the systematic literature review. The Figure 3.1 provides an overview of the SLR process.\n\nThe steps we followed to conduct the SLR are identification of keywords, formulation of search strings, devising of inclusion/exclusion criteria, devising of quality criteria, conducting the database search, selection of initial set of primary studies, applying snowballing technique to the primary studies, obtaining a final set of primary studies, data extraction and analysis. The snowballing approach was opted along with database search to ensure no important studies were missed.\n3.2 Search Strategy\n\nInitially, a database search was conducted to obtain the primary studies, and then snowballing technique was performed to ensure that all relevant studies were covered. Keywords were identified from the research questions, and search strings were generated by combining these keywords using the Boolean operators \"AND\" and \"OR\". Synonyms of the keywords were also added to the search strings to ensure that all relevant studies are obtained.\n\nThe keywords identified for this study are: DevOps, Benefits, Challenges, Principles, Practices, Software Development, Development, Operations.\n\nThe following scientific databases were chosen for conducting the search of relevant studies:\n\n- ACM Digital Library\n- IEEE Xplore\n- Inspec\n- Scopus\n- SpringerLink\n\nThe different databases were selected to ensure complete study coverage. Inspec covers most of the articles from IEEE Xplore and ACM databases. Scopus covers most of the articles from ACM, IEEE Xplore and SpringerLink. However, since there is not much literature available on DevOps, all of these databases were searched thoroughly by running search strings individually on each database to ensure no studies are missed out. The search strings used on each database are listed in the Table 3.1.\n3.3 Inclusion/Exclusion Criteria\n\nThe following inclusion/exclusion criteria has been defined to remove irrelevant and duplicate studies from the database search results. This criteria is later applied to the search results to obtain a set of primary studies.\n\n3.3.1 Inclusion Criteria\n\n- Studies that are available in English language.\n- Studies that are available in full text.\nChapter 3. Systematic Literature Review\n\n- Conference articles and journal articles.\n- Studies published between 2011-2016 (as the research started from 2011 only).\n- Peer-reviewed studies.\n- Studies that focus on the organizational aspects of DevOps.\n- Studies that focus on the benefits, challenges of adopting DevOps in organizations.\n- Studies that focus on the principles and practices of DevOps.\n\n3.3.2 Exclusion Criteria\n\n- Studies that are not available in English language.\n- Studies that are not available in full text.\n- Duplicate studies.\n- Grey literature.\n- Studies that focus only on cloud computing.\n\nAfter the database search, a total of 643 studies were obtained from all the selected databases. Of these, 67 studies were obtained from ACM Digital Library, 88 from IEEE Xplore, 81 from Inspec, 163 from Scopus, and 244 from SpringerLink. After applying the inclusion/exclusion criteria, we were left with 27 studies.\n\n3.4 Quality Assessment Criteria\n\nThe following quality criteria has been devised to assess the quality of the selected studies. Kitchenham et al. [25] state that quality assessment is critical to determine the strength of the inferences of primary studies. The quality criteria is applied to the finalized set of primary studies obtained after the database search and snowballing procedures.\n\n- Are the aims and objectives of the research clear?\n- Does the study report on the benefits of adopting DevOps in software organizations?\n- Does the study report on the challenges faced while adopting DevOps in software organizations?\n- Does the study describe about the various DevOps principles and practices?\n- Is the research methodology clearly specified?\n- Are the results of the research clear?\n- Are the conclusions of the research clearly stated?\n• Are the threats to validity mentioned?\n\nFor each study, we check if the above criteria is met by answering each question with either \"Yes\", \"No\" or \"Partially\".\n\n3.5 Snowballing\n\nSnowballing is another way of conducting searches to identify primary studies. In this search approach, new studies are identified by looking into the references and citations of selected studies. The principal reason in choosing snowballing along with the database search is that formulating a search string with the terminology may not provide us with all the relevant studies. Performing a search in the databases with the search string may give a huge number of studies which can be irrelevant, unnecessary and sometimes can be beyond the perspective [54] [25]. The database search requires creating different search strings for different databases, because the databases are confined to particular methods of searching. The changes in search strings may not provide all the relevant literature, and the threat of losing important literature needs to be mitigated. In his research, Wohlin [54] stated with an example that there is a chance of losing the literature while performing the database search. He also explained that these references can be found by using the snowballing procedure. Hence, snowballing method is considered along with the database search, based on the claims made by Wohlin [54] in this research.\n\nUsing the references of selected studies to find new studies is called backward snowballing, while using the citations of selected studies to find new studies is called forward snowballing [2]. The backward and forward snowballing should be carried out in iterations. The newly identified studies should be added to the selected start set, and snowballing of the new papers should be done again in the next iterations, until no papers are found [2]. In our study, we conducted backward and forward snowballing to the set of 27 studies obtained after applying the inclusion/exclusion criteria to the database search results.\n\nBackward snowballing was conducted in one step, and forward snowballing was conducted in one step. Seven new studies were identified after using the snowballing technique. The citations of studies were identified with the help of Google scholar. Of the seven obtained studies, four were selected as primary studies after applying the inclusion/exclusion criteria. All the new studies were obtained in a single iteration because their references were either grey literature or matched our specified exclusion criteria, and their citations were also found to be irrelevant after applying the inclusion/exclusion criteria. The Figure 3.2 describes the selection of primary studies after database search and snowballing.\n3.6 Data Extraction and Synthesis\n\n31 primary studies were selected for conducting the systematic literature review. A data extraction form was designed according to the guidelines specified by Kitchenham et al. [25] to record the data obtained from the primary studies. The following form was designed to extract the data relevant to RQ1, RQ2 and RQ4.\n### 3.7 SLR Results\n\n31 primary studies were identified for this research. The primary studies and their identifiers are listed in the appendix A. After conducting the database search and snowballing, 31 primary studies relevant to the study were found. All the studies were published between the years 2011 to 2016, while one study [S29] was published in 2008. The year wise distribution of primary studies is presented in the following figure.\n\n\n\n#### Figure 3.3: Year wise Distribution of Primary Studies\n\nFour studies were published in 2011, and one study was published in 2012. It can be seen that the research on DevOps has increased since 2014. Nine studies were published in 2014, seven in 2015 and nine in 2016. Among the 31 studies, 22 studies report on the benefits of adopting DevOps in organizations, 7 studies report on the DevOps adoption challenges, and 10 studies address the principles and practices of DevOps. A detailed analysis of the literature is provided in the next sections. Thematic analysis was followed to analyse the extracted data. The extracted data was color coded, and the identified codes were categorized into the themes \"Benefits\", \"Challenges\" and\n\"Practices\". A detailed analysis of the literature is presented in the next subsections.\n\n3.7.1 **Analysis of Literature Regarding the Benefits of Adopting DevOps in Organizations**\n\nIn this section, we analyse the primary studies regarding the benefits of adopting DevOps in organizations. One objective of this study is to identify how implementing DevOps in organizations where agile development is in practice helps them. The perceived benefits of DevOps adoption are listed by the studies [S1] [S2] [S3] [S4] [S5] [S6] [S7] [S8] [S9] [S10] [S11] [S12] [S13] [S14] [S16] [S17] [S18] [S19] [S20] [S29] [S30] [S31].\n\nIt is to be noted that most of the identified benefits are the perceived benefits of adopting DevOps in organizations. Many companies have started to adopt DevOps these days in an attempt to leverage the benefits [22]. Stilwell and Coutinho [S2] reported on the benefits achieved after implementing DevOps in a research project. They observed a qualitative difference in the way teams operate after implementing a DevOps workflow. They found that teams could meet the project milestones with more speed and efficiency. Virmani [S9] reported on a case study conducted at IBM, and he has identified several benefits of adopting DevOps in organizations. Callanan and Spillane [S14] reported that after implementing DevOps in their company Wotif, there was a significant improvement in the average release cycle time. Erich et al. [S3] conducted a mapping study on the cooperation between the development and operations teams in organizations, and they found that DevOps has a positive effect on the performance of both development and operations teams, and also quality assurance teams. They also found that DevOps has a positive impact on web service development. Nybom et al. [S20] conducted interviews in an organization and identified the benefits of shared responsibilities between Dev and Ops. They found that DevOps increases the trust and collaboration, and improves the workflow. Tessem and Iden [S29] identified that good cooperation between development and operations teams is essential for successful software deployment and operation, way before the term DevOps was coined.\n\nThe following benefits have been identified from the primary studies:\n\n- The communication, collaboration and trust between development and operations team members increases [S1] [S9] [S10] [S20].\n- Improved quality of software deployment [S1] [S17].\n- Responsiveness to business needs increases [S1].\n- The software reliability increases [S1].\n- The code quality will be improved [S1].\n- Implementing the customer requirements throughout the software development process becomes easier [S1].\nChapter 3. Systematic Literature Review\n\n- Development teams will be able to operate autonomously, while being more open to changes and providing frequent updates [S2].\n- The communication overhead for making coordinated changes reduces [S2].\n- DevOps is supported by structures and standards, and it also facilitates the realization of the structures and standards which are advantageous for development and operations [S3].\n- Frequent software releases [S1] [S4] [S6] [S30] [S31].\n- Overcomes the gap between development and operations teams [S4] [S5] [S6] [S7].\n- It solves important issues like fear of change and risky deployments [S8].\n- The time to market is reduced [S9] [S31].\n- Continuous feedback will be enabled [S9].\n- Cost and quality will be balanced out [S9].\n- Increased predictability in releases [S9].\n- The overall organization’s efficiency will be increased [S9].\n- The cycle times of operations activities such as deployment and change controls will be reduced [S10].\n- Continuous improvement will be encouraged as a means to automation of tools and processes, and also for adapting to the quick changes in the software environment [S10].\n- Increases revenue of the organizations [S11].\n- Reduces costs by reducing the need for rework [S11].\n- Problems can be detected earlier, and can be solved efficiently and effectively [S12].\n- Reduced time to software release [S13].\n- Reduces the average release cycle time from weeks to hours [S14].\n- Rapid delivery of products [S16].\n- Increased customer satisfaction [S30].\n- DevOps quantifies the aspects of the development process, and the focus on metrics subsequently improves the product development [S18].\n- DevOps helps to deliver higher quality services in a more efficient way [S19].\n- Smooth and faster work flow [S20].\n3.7.2 Analysis of Literature Regarding the Challenges of Adopting DevOps in Organizations\n\nIn this section, we analyse the primary studies regarding the challenges faced while adopting DevOps in organizations. Identifying the challenges to DevOps adoption in organizations is another aim of this research. The possible challenges to DevOps adoption are identified by the studies [S1] [S20] [S21] [S22] [S23] [S24] [S25].\n\nOnly few studies address the challenges to DevOps adoption in organizations. Several hindrances to the DevOps adoption process in the cloud services area have been identified by Smeds et al. [S21]. They conducted interviews in an IT organization with over 1000 employees, and identified 11 challenges in the initial stage of DevOps adoption process. Jones et al. [S24] conducted a case study in a SME (Small and medium-sized enterprise) having over 200 employees and identified the challenges to DevOps adoption within that organization. At that time, the organization had a legacy system, and a new system was being developed as a replacement for the legacy system. Lwakatare et al. [S25] identified the challenges to adoption of DevOps in the embedded systems domain by using a multi-case study approach with four companies.\n\nThe challenges that occur while adopting DevOps in organizations are:\n\n- A lack of proper management structure in an organization can hinder the adoption process [S1] [S24].\n- There is no proper training in place for DevOps in several organizations, so the DevOps engineers are usually hired based on their experience as system administrators and software developers [S1].\n- Unclear definition and goals of DevOps adoption [S21].\n- Organizational structure may impact the DevOps adoption process [S21].\n- In some cases, the customer might fancy a different approach of development, such as including different practices and process with strict procedures on deployment. DevOps might not be suitable for product development in these cases [S21].\n- Geographical distribution of the development and operations teams can hinder the DevOps adoption [S21].\n- People may perceive DevOps as a buzzword, and this negative perception may cause them to try to resist its adoption [S21].\n- Developers may be afraid that DevOps will overburden them with operations responsibilities, and reduce their working efficiency [S21].\n- Because DevOps requires all personnel to have both development and operations skills, people may not be open to the change due to fear of not having in-depth expertise in both areas [S21] [S20].\n• People may be interested in only their area of expertise, not in what other teams do [S21].\n• Monolithic system architecture can be hindering to the various DevOps practices like continuous builds, testing and deployment [S21].\n• Differences between the development, testing and production environments can complicate the collaboration and also continuous delivery and deployment [S21].\n• Multiple production environments can cause complexity, and hinder the use of common tools and processes, which can affect continuous delivery [S21].\n• Moving to DevOps is more difficult with legacy software [S22] [S24].\n• Specifying the software architectures to make them work in DevOps scenarios can be challenging for software architects [S23].\n• Lack of buy-in from senior management can be challenging [S24].\n• Resistance from employees can also hinder the adoption process [S24].\n• Hardware dependency and compatibility with different software versions [S25].\n• Limited visibility of customer production environments when configuring test environments [S25].\n• Lack of automation tools for deployment of new features in the embedded systems domain [S25].\n• If the system performance data collected by companies does not contain feature usage data, it hinders DevOps adoption [S25].\n\nSeveral challenges were identified by Smeds et al. [S21] after interviewing software practitioners in a single software organization. They note that if the teams do not have a clear view on the definition of DevOps, they might misunderstand the goals and the actions needed to achieve these goals. They identified organizational structure as another challenge. Another addressed challenge was that the DevOps processes and practices might not be compatible with the processes and practices required by the customer. Geographical distribution of development and operations teams was identified as another challenge. If the teams are in different time zones, it can lead to communication issues and process related issues. The perception of DevOps as a buzzword by the personnel was identified as another challenge.\n\nSmeds et al. [S21] note that because of the fuzzy definition of DevOps, many personnel lacked trust in the concept, and there was an opinion that the activities termed under DevOps were not that different from the activities practised before the term was coined. They state that this perception could lead to resisting change. Another challenge identified was that developers were concerned that their workload might increase due to DevOps, and the new responsibilities might affect their focus and productivity. Lack of interest in what the other teams do was identified as a challenge. It was noted\nthat several personnel were interested only in their area of expertise.\n\nSmeds et al. [S21] identified monolithic architecture as a huge challenge. They state that system architecture affects the way the system is developed, tested and deployed, and monolithic architecture can hinder the continuous builds, testing and deployment. Another addressed challenge was the difference between development, testing and production environments. If the development and testing environments do not reflect the production environments, there is a risk of the software not being properly validated before it is deployed to production. This can complicate not only continuous delivery and deployment, but also the collaboration. The developers are familiar with development and testing environments, but not production environments. Thus, because of the differences between environments, the use of production environments will be challenging to the developers, which affects the collaboration. Having multiple production environments was identified as another challenge. They state that the differences between multiple production environments hinder continuous delivery. It was noted that use of different environments causes complexity, and also hinders automation and use of common tools and processes.\n\nIn their case study, Jones et al. [S24] identified that lack of proper management structure can hinder the adoption process. In the organization on which they conducted their research, the adoption of DevOps was a bottom up process, led by a software development manager. The software development manager had to convince the senior manager on the benefits of DevOps. Further, there was resistance from the operations teams in that organization because they had the opinion that coding was a developer responsibility. They also found that maintenance of legacy systems is a major issue faced by the developers, and it also affects learning of new technologies. In this case study, the developers were developing a new system, and they expressed the opinion that maintenance of legacy system interrupted the new system development. Thus, Jones et al. identified the DevOps adoption challenges as lack of proper management structure, lack of buy-in from senior management, legacy systems and resistance from employees.\n\nLwakatare et al. [S25] identified the challenges to DevOps adoption by conducting a multi-case study in four software companies that developed embedded systems. The first challenge is hardware dependency and compatibility with different versions of software. They identified that because of hardware dependencies, the companies had silos of development teams for different modules, which resulted in longer development cycles. This led to delays in release of new features to customers. It was also identified that the companies had limited visibility of the customer production environments, which complicated the configuration of testing environments. DevOps stresses on testing features in a production-like environment, and the limited visibility of production environments in embedded systems hinders the adoption process. Another challenge identified was the lack of automation tools to continuously deploy new fea-\ntures in the embedded systems domain. It was noted that the companies collected the system performance data, but feature usage data was missing in it. The feature usage data helps to continuously improve products. Thus, lack of feature usage data was identified as a challenge to DevOps adoption.\n\n3.7.3 Analysis of Literature Regarding the Practices of DevOps\n\nIn this section, we analyse the literature regarding the various practices of DevOps. Identifying the practices to be included by the organization as a part of the adoption process is another aim of this research. The different practices of DevOps are listed by the studies [S9] [S15] [S18] [S21] [S22] [S25] [S26] [S27] [S28] [S30].\n\nFor an organization, it takes a lot of effort to process the adoption of a different methodology. They need to change their infrastructure, the organizational structure, the development strategy, and continuous involvement of operation team. The organization must include some practices into their development processes as a part of the adoption process. Adoption of DevOps takes a great amount of collaboration with in the organization as it requires revamping of that organization. The focal part in DevOps adoption is that the integration between software development and its operation deployment should happen continuously [16]. In order to embrace this change, the organizations must follow some principles and practices.\n\nThe adoption of DevOps takes down the wall in between the development and the IT operations by making them work towards achieving a common goal throughout the process [30]. DevOps is a process that includes the principles and practices to synergize the development and operations departments in the organization [12]. The organization should enable the communication and coordination in between the development and operations departments as it leads to better performance of both the teams [19]. As the continuous work in between the DevOps teams takes place, the organization should get accustomed to some activities such as continuous planning, continuous integration, continuous testing, continuous deployment which supports continuous innovation [17].\n\nThe principles and practices in DevOps are related to the aspects of Culture, automation, measurement, and sharing [16].\n\nCulture: DevOps is more of a merger of development and operations. So, both the departments hold the joint responsibility of delivering high quality software to the end user. Consequently, the code can no longer be “thrown over the wall”.\n\nAutomation: To achieve quicker delivery, feedback from end users and short lead time, DevOps counts on complete automation of the build, deployment and testing.\n\nMeasurement: Comprehending the capability of current delivery and setting goals for\nits improvement can only be done by measuring. This measurement varies from monitoring business metrics to test coverage and deployment time of a new software version.\n\nSharing: Sharing of knowledge, tools, culture, infrastructure and success as well can make the development and operations team closely acquainted.\n\nSmeds et al. [S21] defined DevOps as a \"set of engineering process capabilities supported by certain cultural and technological enablers.\" They have identified the enablers as automation, sharing, and communication. The capabilities, in other words, are the practices that an organization should include [S21]. Thus, the organization needs to follow the principles of automation, sharing and communication in order to support the technical practices.\n\nThe following practices of DevOps have been identified from the literature [S9] [S15] [S18] [S21] [S22] [S25] [S26] [S27] [S28] [S30]:\n\n- Continuous Planning\n- Continuous Integration\n- Continuous Deployment\n- Continuous Delivery\n- Continuous Testing\n- Continuous Monitoring and Feedback\n\n**Continuous Planning:**\nTo aid the development and operations teams to adjust to the rapid changes in business environments, there is a need to have agile business plans in place. DevOps enables this by having a product backlog which can be prioritized all the time, and a continuous channel for feedback from customers. It is important that planning is done frequently to cope with quick changes in business environments, and there needs to be tight integration between planning and execution. The continuous planning is a cyclic process, and achieved by planning small batches, executing, obtaining feedback, responding to the feedback and adjusting the plan if needed.\n\n**Continuous Integration:**\nContinuous integration necessitates a connection between development and operations teams. To achieve this, integration must be done early, changes should be shared with teams without keeping them localized for long, and code should be validated continuously. Continuous integration requires some form of automation, and has interconnected steps like compiling code, running unit and acceptance steps, validating code coverage and building deployment packages. Automation must be done in such way that as soon as a developer makes a change, it is detected by the build system and a build is triggered, sanity tests are carried out, and the build is posted to a repository.\nThis needs to be a repeatable and continuous process. It is important that there are highly visible artefacts in case of continuous integration failures so that the problems which caused the failure are fixed as early as possible by the responsible personnel.\n\n**Continuous Deployment:**\nContinuous deployment involves automatically deploying the software to some environment, but not necessarily to the customers. Continuous deployment is a prerequisite for achieving continuous delivery. Virmani [47] states that continuous deployment is a critical step in overall software delivery optimization. DevOps principles recommend automation of deployment and provisioning of hardware. Manually configuring the hardware to test builds can take up to several weeks of time, and the deployment processes will not be consistent. Another principle of DevOps comes into play in continuous deployment; Infrastructure as code (IaC), which implies that infrastructure is maintained as code in the source code repository.\n\n**Continuous Delivery:**\nContinuous delivery involves automatically releasing valid software builds to the customers. Continuous deployment is necessary for achieving continuous delivery, but the reverse is not usually the case. Continuous delivery is the ability to deliver software whenever the organization wants to. In continuous delivery, as soon as new features are finished, they are deployed into production.\n\n**Continuous Testing:**\nAutomation of all test cases is necessary to achieve continuous testing. Existing manual test cases should be automated, and the test cases should be executed on every generated software build without any manual intervention. Continuous testing aims at eliminating root causes and involves automation of testing cases so that the time between introduction and detection of errors is reduced.\n\n**Continuous Monitoring and Feedback:**\nContinuous monitoring of infrastructure and user-behavior provides feedback loops for the planning and development processes to improve and optimize the service. Different quality parameters can be observed, and we can react to any surprises in a timely manner. In DevOps, feedback is the data collected from operating the service as an input in planning and development. This data contains information about the performance of infrastructure, and how and when the users interact with the service.\n\n### 3.8 Discussion and Conclusion\n\nAmong the 31 primary studies identified through database search and snowballing, 22 studies address the benefits of adopting DevOps in organizations, 7 studies discuss about the DevOps adoption challenges, and 10 studies discuss about the principles and\npractices of DevOps. There is currently very little high-quality literature related to DevOps as it is a very new topic, but a slight growth in the number of studies in this domain since the past two years has been observed. Many authors have stressed on the need to conduct further and extensive research on DevOps. The main objectives of this study are to identify the benefits of adopting DevOps, the challenges faced by organizations while adopting DevOps, and the different practices that organizations must include for adopting DevOps. By conducting the SLR, we were able to answer three of our research questions, RQ1, RQ2 and RQ4.\n\nOur research aims at identifying the benefits of implementing DevOps in organizations where agile development is in practice. However, the perceived benefits of adopting DevOps in organizations in general were identified from the literature. Several studies mentioned the perceived benefits of adopting DevOps. It was observed that many organizations have started to adopt DevOps because of the perceived benefits like increased frequency of software releases, improved quality of software deployments, reduced time to market, increased customer satisfaction, etc [47] [22]. Stilwell and Coutinho [S2] noted a qualitative difference in the way teams operate, and observed that the teams were able to meet project milestones with more speed and efficiency after implementing DevOps in a research project. Callanan and Spillane [S14] reported a significant reduction in the average release cycle time after adopting DevOps in their company. Nybom et al. [S20] noted that DevOps increases trust and collaboration between teams, and improves the workflow. Several other perceived benefits of adopting DevOps were identified from the literature. The benefits identified from the literature will be ascertained after interviewing DevOps practitioners.\n\nWhile the popularity of DevOps is attracting many companies to adopt it, it has been observed that adoption of DevOps is not easy. Despite the perceived benefits, organizations may face several challenges while adopting DevOps. Only 7 studies report on the DevOps adoption challenges. Smeds et al. [S21] identified several DevOps adoption challenges after conducting interviews in an IT organization. Jones et al. [S24] identified the challenges to DevOps adoption after conducting a case study in a SME. The challenges to DevOps adoption in the embedded systems domain were identified by Lwakatare et al. [S25] after conducting a multi-case study in four companies. The mostly stated challenges were identified as lack of a proper management structure, resistance from employees, fear of change, and legacy software. Several other generic challenges like lack of training related to DevOps, unclear definition and goals of DevOps adoption, geographical distribution of Dev and Ops teams, monolithic system architecture, lack of proper automation tools, etc. were identified from the literature. The DevOps adoption challenges identified from the literature will be further ascertained after conducting interviews.\n\nAnother aim of the study is to identify the practices that an organization must include while adopting DevOps. It has been observed that organizations need to adopt certain\nprinciples, and include certain technical practices as part of the DevOps adoption process. 10 studies address the principles and practices of DevOps, but it was seen that there is no clear definition of the various DevOps principles and practices in the literature. The principles of DevOps were observed to be culture, communication, sharing and automation. As specified by Smeds et al. [S21], the principles are the enablers of the technical practices. To include the technical practices, organizations must mainly follow the principles of culture, automation, sharing and communication. The technical practices were identified to be continuous planning, continuous integration, continuous deployment, continuous delivery, continuous testing, continuous monitoring and feedback. The principles are needed to support the technical practices of DevOps. The identified DevOps practices will be validated, and explained in detail after interviewing the DevOps practitioners.\n\n3.9 Threats to Validity\n\nWhile performing the SLR, there are some validity threats that could occur. These threats need to be addressed in order to make the data more definite, and because disregarding these threats can make the interpretation go wrong. These threats are identified and are narrowed down by using the validity categories provided by Wohlin et al [55]. They are:\n\n1) Internal Validity:\nThe authors have performed snowballing along with database search to acquire maximum literature in the research area. While performing this search, internal validity can be the one of the major threats for this study. This threat can be mitigated by performing some procedures such as formulating a search string. The search string was formulated with the help of librarian, and verified by the supervisor. With the help of search string, a database search was conducted and the literature obtained from the search was gathered. This literature was refined by applying inclusion and exclusion criteria, where the articles which are irrelevant to the research area were excluded. For example, the studies related to cloud were not considered. In addition to database search, snowballing was performed to not skip any important studies relevant to our work. The snowballing process was carried out in iterations. After performing the above mentioned steps, quality criteria was defined to assess the studies obtained from the database search and snowballing procedures. Thus the threat of publication bias is reduced. The finalized list of primary studies was taken into consideration after the quality assessment. The whole process was carried under the observation of the supervisor. The supervision aided us as the process was checked again, and the steps performed were also verified by the supervisor.\n\n2) Construct Validity:\nConstruct validity aims at possible confounding factors, whether the study has the ca-\nChapter 3. Systematic Literature Review\n\nThe capability of focusing on its aim and objectives. These threats were reduced by planning the sections accordingly based on the research questions and delineating the sections. Another threat is the search string, as the relevant studies should be searched for thoroughly, or there is a risk of missing the literature. This was eliminated by formulating the search string with the help of librarian, and getting it verified by the supervisor. Another threat which needs to be considered is, while performing snowballing there is a possibility of finding the same author, or same studies. To reduce this risk, those studies were excluded.\n\nThe other threats that could happen are that there is a chance of missing significant information from the literature. While focusing on documenting, the authors might skip the information in the literature, which may lead to missing the important information for the research. To mitigate this threat, the authors have maintained an excel sheet where every important data related to the primary study were listed out separately, which avoids the uncertainty in finding the information when required. The data extraction forms aided the authors in listing out the information.\n\nThe other possible threat that might affect the literature is the domain applicability. Since there is less literature available in the research area, the search string may provide the articles related to cloud computing, health care, agile methodologies. As the study is completely focused on the adoption of DevOps in organizations, those studies should be excluded. To mitigate this threat, the search string was framed by using the keywords related to the domain, and quality assessment was performed so that the studies which have irrelevant literature and improper data are excluded. The quality assessment helped the authors in finding quality literature and contributed well to the documentation of the research.\nChapter 4\n\nAnalysis of Interview Data\n\nIn this chapter, the data analysis and results of the interviews conducted are described.\n\nThe target population for interviews is software engineering practitioners that have worked with DevOps. A non-probabilistic sampling method, convenience sampling was employed for selecting the interview respondents. The interviewees were selected from personal contacts, and practitioners on LinkedIn. Convenience sampling refers to gathering responses from people who are available and willing to respond [41]. The motivation behind choosing non-probabilistic sampling is because the target population is specific and limited. DevOps is a relatively new phenomenon, and organizations are only recently becoming familiar with it. It is thus hard to rely on a random sample.\n\nA semi-structured interview questionnaire having both open-ended and close-ended questions was initially designed based on the SLR findings, and improvised according to the feedback from the supervisor. Questions related to interviewee demographics and the present study were included. The questions were related to the benefits of adopting DevOps in organizations, challenges faced during the adoption process, strategies to overcome these challenges, the different DevOps practices, and the problems that DevOps teams face during continuous integration, deployment and testing.\n\nA total of 12 interviews were conducted with 12 different software practitioners from 11 different organizations. All the 12 interviewees were asked the same set of questions, and spontaneous questions were asked whenever needed. The interviews were conducted using Skype. The interviewees were promised confidentiality to get them to give genuine and detailed answers. Audio recording was done in all interviews to collect the data. All the interviewees gave permission for audio recording. Thematic analysis was done to analyse the collected data. The following steps are followed to analyse the interview data:\n\n- Transcribing data\n- Organizing data\n- Reading through all the data\n- Coding the data\n- Identifying themes\n- Interpreting the meaning of themes\nTranscribing refers to writing down the recorded audio data. All the recorded data from each interview was transcribed into separate word documents. Everything spoken by the interviewees was transcribed manually, without leaving any word in order to avoid bias. The transcripts were organized by assigning individual IDs for each transcribed interview document, to avoid confusion and facilitate easier data analysis. All transcripts were thoroughly read to familiarize with the data, and get a clear understanding. Codes in each transcript were identified by manually examining the transcripts. Each code was highlighted with a different colour, based on the question. The identified codes were classified into themes based on their similarities and relevance. The authors have defined the code inclusion criteria as frequency and relevance. In our research context, frequency refers to the responses specified by more than one respondent, and relevance refers to both relevance to the literature, and the relevance to our research.\n\n### 4.1 Demographics of Interviewees\n\nThe demographics of the interviewees are presented in this section. To preserve the anonymity of the interviewees, they are assigned individual IDs, and are referred to as Interviewee 1, 2, etc. Among the 12 interviewees, six are from India, four are from Sweden, and two from USA. As most of the respondents are not in Sweden, face-to-face interviews were not possible. Also, the interviewees from Sweden were not located in the same part of Sweden as the researchers. Thus, Skype interviews were conducted. Most of the interviews lasted for 45-60 minutes. The interviewees 2 and 9 are from the same organization. The roles of the interviewees, size of their organizations, and the experience of the interviewees with DevOps is presented in the Table 4.1.\n\n<table>\n<thead>\n<tr>\n<th>Interviewee ID</th>\n<th>Location</th>\n<th>Role</th>\n<th>Organization Size</th>\n<th>Experience</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>I1</td>\n<td>India</td>\n<td>Developer</td>\n<td>> 5000</td>\n<td>1 year</td>\n</tr>\n<tr>\n<td>I2</td>\n<td>India</td>\n<td>Build/ Release Engineer</td>\n<td>> 3000</td>\n<td>3 years</td>\n</tr>\n<tr>\n<td>I3</td>\n<td>USA</td>\n<td>DevOps Consultant</td>\n<td>2500</td>\n<td>3 years</td>\n</tr>\n<tr>\n<td>I4</td>\n<td>India</td>\n<td>Build/ Release Engineer</td>\n<td>> 5000</td>\n<td>1.5 years</td>\n</tr>\n<tr>\n<td>I5</td>\n<td>India</td>\n<td>System Administrator</td>\n<td>50</td>\n<td>7 months</td>\n</tr>\n<tr>\n<td>I6</td>\n<td>Sweden</td>\n<td>Professional Services Engineer</td>\n<td>50</td>\n<td>1 year</td>\n</tr>\n<tr>\n<td>I7</td>\n<td>USA</td>\n<td>Senior Specialist</td>\n<td>> 5000</td>\n<td>1 year</td>\n</tr>\n<tr>\n<td>I8</td>\n<td>Sweden</td>\n<td>Senior Software Engineer</td>\n<td>50</td>\n<td>2 years</td>\n</tr>\n<tr>\n<td>I9</td>\n<td>India</td>\n<td>Operations</td>\n<td>> 3000</td>\n<td>1.5 years</td>\n</tr>\n<tr>\n<td>I10</td>\n<td>Sweden</td>\n<td>Software Developer</td>\n<td>50</td>\n<td>6 months</td>\n</tr>\n<tr>\n<td>I11</td>\n<td>Sweden</td>\n<td>DevOps Consultant</td>\n<td>10</td>\n<td>4 years</td>\n</tr>\n<tr>\n<td>I12</td>\n<td>India</td>\n<td>Build/ DevOps Engineer</td>\n<td>> 5000</td>\n<td>1 year</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.1: Demographics of Interviewees\n4.2 Codes and Themes for RQ1\n\nA total of 20 codes for the benefits of adopting DevOps in organizations where agile development is in practice were identified from the 12 interview transcripts. The codes were selected based on the inclusion criteria relevance to study, and frequency of occurrence. The identified codes were categorized into the theme \"Benefits\". The Table 4.2 presents the codes and themes identified for RQ1.\n\n<table>\n<thead>\n<tr>\n<th>Codes</th>\n<th>Code Inclusion Criteria</th>\n<th>Themes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Faster feedback</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Reduced release cycle time</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Reduced gap between Dev and Ops teams</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Rapid Delivery</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Automation</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Increased empathy between Dev and Ops teams</td>\n<td>Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Increased communication between Dev and Ops teams</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Rapid time to market</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Easier tracking and collaboration</td>\n<td>Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Breaks down silos</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Improved code quality</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Increased system stability</td>\n<td>Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Minimizes manual intervention</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Saves time and effort</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Reduced human error</td>\n<td>Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Increased agility</td>\n<td>Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Implementing business requirements in a faster way</td>\n<td>Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Earlier detection of failures</td>\n<td>Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Reduces cost</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n<tr>\n<td>Faster workflow</td>\n<td>Frequency, Relevance</td>\n<td>Benefits</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.2: Codes and Themes for RQ1\n\n4.2.1 Analysis of Interview Responses for RQ1\n\nIn this section, we analyse the codes related to the benefits of adopting DevOps in organizations where agile development is in practice. 20 codes were identified from the 12 interviews, and grouped into the theme \"Benefits\".\n\nBenefits: All the interviewees discussed about the advantages of implementing DevOps where agile development is in practice. It is to be noted that agile methodologies were followed in organizations of all the interviewees before adopting DevOps. Three interviewees 1, 2, 9 expressed that DevOps enables faster feedback. Interviewee 2 said,\n\"Feedback is one of the best practices of DevOps.\" Interviewee 9 said, \"Previously, we used to release only after the entire product is complete. Now (after adopting DevOps), we deliver small Minimum Viable Products (MVPs). We release each MVP and the customers give us feedback. Based on that feedback, we improve the product, which will incrementally improve the value.\"\n\nReduced release cycle time was identified as another benefit from interviews 1 and 12. Interviewee 1 said, \"Previously, the release cycle was two weeks. After adopting DevOps, we were able to bring down the release cycle to three days. One of the reasons to adopt DevOps is to expedite the release process.\" Reduced gap between Dev and Ops teams was identified from 1, 12 interviews. Rapid delivery was identified from interviews 2, 4, 7, 8, 12. Interviewee 2 said, \"With DevOps, builds, deployments and testing will be done in an automated fashion. Because of this, the time taken will be reduced from 6 hours to at the most, 30-35 minutes.\" Interviewee 4 said that speed of delivery was the ultimate achievement in their organization. Interviewee 10 stated that the delivery speed in their organization increased by 30-40 percent after adopting DevOps. Interviewee 12 commented that because of automation, the delivery speed increased in their organization.\n\nIt has been noted that many interviewees perceived automation in DevOps as a benefit. Interviewee 2 said, \"Another good thing about DevOps is automation. There is no manual intervention in any of the stages.\" Interviewee 6 said, \"Automation saves time and gives quick results. Previously, we had to maintain test beds, test servers, systems and so on. For that, one system takes around 45 minutes. Once we automated these processes, it hardly takes about 5 minutes for everything.\" Interviewee 9 said, \"Minimum human intervention and maximum automation yields better results in terms of delivery speed and quality.\" Interviewee 9 also noted that some people argue that automation causes unknown side effects. He said that some people may have a misconception that automation does all the work, and thus overlook things which need to be checked rigorously. Interviewee 12 commented that because of automation, human intervention would be reduced, and delivery speed would increase.\n\nIncreased empathy between Dev and Ops teams was identified as another benefit. Interviewee 11 commented \"What does it really need for the developer to understand the situation of the tester or an operations person? Empathy. So, one of the key ingredients for DevOps is empathy towards other human beings that you have to work with.\" Increased communication between Dev and Ops teams was identified from interviews 2 and 3. Rapid time to market was identified as a benefit by interviewees 8 and 9. Easier tracking and collaboration was identified as a benefit. Interviewee 4 commented that \"Earlier, the developer used to handover code to the repository, and builds were made, then QA (quality assurance) team used to test it and push it to production, and so on. But now the control is under everyone’s hand, and it is easy to track and collaborate and work to get the job done.\" Another benefit identified was that DevOps breaks down si-\nImproved code quality and increased system stability were identified from interview 4. Interviewee 4 stated that the code quality is high as it gets checked at every batch set, and the system is more stable. Interviewee 12 said, \"There will not be any walls between the teams, and everyone can see what is going on. Because of this visibility, collaboration will be enhanced and problems can be easily solved. This will improve the code quality.\" Interviewee 5 commented that DevOps minimizes manual intervention. He pointed out that as a result, human error can be avoided. He said that \"Human error could mess up the environments.\" Another advantage identified from interview 5 was that DevOps saves time and effort. Increased agility in the organization was identified as an advantage from interview 6. Interviewee 9 commented that using DevOps, business requirements can be implemented in a faster way. He also added that DevOps enables earlier detection of failures. Interviewees 10 and 12 stated that DevOps reduces the delivery time and development cost. Interviewees 4, 11 and 12 commented that DevOps results in a faster workflow.\n\n4.3 Codes and Themes for RQ2\n\nA total of 20 codes for the challenges faced by organizations while adopting DevOps were identified from the 12 interview transcripts. The codes were selected based on the inclusion criteria relevance to study, and frequency of occurrence. The identified codes were categorized into the theme \"Challenges\". The Table 4.3 presents the codes and themes identified for RQ2.\n\n4.3.1 Analysis of Interview Responses for RQ2\n\nIn this section, we analyse the codes related to the challenges faced while adopting DevOps in organizations. 20 codes were identified from the 12 interviews, and grouped into the theme \"Challenges\".\n\nChallenges: All the 12 interviewees agreed that DevOps adoption can be challenging for organizations that are implementing it for the first time. Changing architecture to support DevOps was stated as a major challenge by interviewees 2 and 9. Interviewee 2 commented by saying, \"In our organization, we have huge applications, and the system architecture is complex. When you adopt DevOps, you need to convert your systems into micro services or a modularized architecture. The advantage with modularized architecture is that if there is any change in the code, only that corresponding module\nChapter 4. Analysis of Interview Data\n\n<table>\n<thead>\n<tr>\n<th>Codes</th>\n<th>Code Inclusion Criteria</th>\n<th>Themes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Changing architecture to support DevOps</td>\n<td>Frequency, Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Insufficient knowledge on applications and environments</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Culture and mindset of long timers</td>\n<td>Frequency, Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Resistance from employees</td>\n<td>Frequency, Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Training</td>\n<td>Frequency, Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Security clearances</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Technical debt</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Lack of collocated teams</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Making everyone accustomed to a new workflow</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Tool adoption</td>\n<td>Frequency, Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Learning curve</td>\n<td>Frequency</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Buy-in from management</td>\n<td>Frequency, Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Writing custom scripts for automating tasks</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Over-burdened personnel</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Hidden complexities and hidden costs</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Fear of measurement in employees</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Integrating different tools</td>\n<td>Frequency, Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Migrating to cloud</td>\n<td>Frequency, Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Lack of proper resources to configure environments</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n<tr>\n<td>Fear of failure in managers</td>\n<td>Relevance</td>\n<td>Challenges</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.3: Codes and Themes for RQ2\n\nneeds to be built. There is no need to build the entire code and risk the schedule. However, to support this conversion, the entire system architecture has to be changed. For this, the entire code base needs to be re-written. This is the main challenge that we faced.\" Interviewee 9 noted that architecting for DevOps is challenging.\n\nInsufficient knowledge on applications and environments was identified as a challenge to DevOps adoption by interviewee 3. He commented that this applies for outsourcing companies. He added that in outsourcing companies, instead of hiring a full time developer, they employ a consulting company that will bring consultants on demand. That means they will hire a consultant only when there is work to be done. \"That way, I don’t have to pay a full time salary, or provide any benefits.\" He stated that there is no guarantee that the same consultant comes in for all projects, and whoever is available on the bench will be brought in by the consulting companies. \"For DevOps to happen, you need to have an intricate knowledge on the applications or environments have been set up. Without that, when someone new comes in they have to learn about them, which takes time. This is not easy when new people are coming in to develop all the time.\"\nChapter 4. Analysis of Interview Data\n\nCulture and mindset of long timers was identified as another challenge by interviewee 3. He added, \"Many organizations will not have the luxury of young development team. They have a lot of people with a long tenure. The culture and mind set of these long timers will be a biggest challenge.\" He cited two other examples which were hindered by mindset of long timers; Disruption from main frames to open systems, and Changing from waterfall to agile methodologies. Interviewee 7 stated that adopting to the DevOps culture change is challenging. Interviewee 5 also stressed on the importance of having a DevOps mindset. He commented that by mindset, he means how much people are motivated to try a new strategy. Interviewee 4 also stated that change in mindset of people can be challenging. He added, \"In my own company, everyone was quite reluctant about following DevOps because all code has to go through certain sets of checks and builds, and essentially the process of landing the change into the repository was delayed or slowed down because of this. But later on, they realized the trade-off between the time taken to fix bugs in production versus fixing the bugs well in advance in Dev phase was way more practical than later phases. Then we got a buy in.\" Interviewee 9 also stated that cultural shift was a challenge. Interviewee 11 said, \"You can’t force culture.\" He added that culture change takes time. Interviewee 12 also shared a similar view. He commented that establishing DevOps culture takes time.\n\nResistance from employees was identified as a challenge by interviewees 9 and 11. Interviewee 11 said, \"There are people who resist the change. They will be like I’m a developer and I have this job description, my responsibilities. I’m a developer and now I have to worry about all these other things. I don’t care about operations or test cases.\" Interviewee 12 also stated that resistance from employees can be challenging. He said, \"Some employees will not really be open to new changes. Because they have this particular job and they know how to do it. When you try to bring a new change, for example, if you tell an operations employee he has to suddenly take part in development activities also, he will try to resist it. The reason is they are scared because they have to learn something new and entirely different. In other words, they are afraid step out of their comfort zones.\"\n\nTraining was identified as a challenge to DevOps adoption by interviewees 3, 4 and 9. Interviewee 9 added, \"Training some 7000-8000 people in the organizational level is not an easy task. People come from different backgrounds like technical, non-technical, financial, business management, etc. Making them to understand things from their level of perspective and bringing them to collaborate is not easy. It takes years of effort. Like 2-3 years of effort.\"\n\nInterviewee 7 stated that security clearance was a challenge faced in their organization. Their organization handles very sensitive data like credit card information. \"Now we are using an IBM tool which can be replaced by Ansible. But for deploying through Ansible, we need root access, for which there is no clearance from the security team. For deploying packages into public cloud like AWS, we need legal clearance from the\nUS security team, which is pending. Though we have inbuilt clouds, it is not as efficient as AWS. We are currently trying to get clearance.\"\n\nInterviewee 3 identified technical debt as a challenge to DevOps adoption. He added, \"There is a right way of coding and a quick and dirty way of doing it. There is no incentive for the developer to do it the right way if it takes longer. He will try to clear backlog asap. Quick and dirty way might not survive for long, which means someone again in the future has to remedy it. So, you are incurring debt now, which you have to pay off in the future. Also, talking about performance goals, if not everyone is measured on the same level, then there is no incentive for the developer to do the right thing in DevOps. In the waterfall methodology, we have peer code review, so someone will uncover it and the developer can be held responsible. This is not the case in DevOps.\" He commented that technical debt is a very bad practice.\n\nLack of collocated teams was identified as a challenge by interviewee 3. He added that if the teams are not collocated at the same geographical location, the number of hand-offs between teams will increase, and communication becomes difficult. This will hinder DevOps adoption.\n\nInterviewee 4 identified making everyone accustomed to a new workflow as a challenge to DevOps adoption. He commented by saying, \"We faced a problem because we had to organize certain trainings in place to bring everyone on the same page. Because no one was used to working in this kind of workflow.\"\n\nTool adoption was identified as a challenge to DevOps adoption by several interviewees. Interviewee 3 commented that most new tools are cloud-based, which is a new concept for long timers. Interviewee 4 stated that adoption of technologies and tools was a challenge faced in their organization. He commented, \"Learning tools was pretty challenging. Once we had full DevOps activity in place, the teams had to learn about puppet (tool).\" Interviewee 9 added, \"Consider open source tools. Unlike in commercial tools, you have to customize and configure them. For that, you need to have a certain level of understanding. Adopting them will not be that easy.\" Interviewee 12 said, \"These days cloud based tools, for example Infrastructure as a Service IaaS tools like Amazon Web Services and google cloud are becoming very popular. Many companies have some predefined tools, called 'Legacy tools' and if they want to adopt DevOps they should make sure that their existing tools are compatible with these IaaS tools.\"\n\nLearning curve was identified as a challenge to DevOps adoption by interviewees 4, 5 and 8. Interviewee 8 added, \"The developers need to know how to set up servers. The operation guys can be new to many things; they knew about all about infrastructure, how to set up servers and how to do it manually. But they need to learn the code. So it can be challenging for everyone.\"\nBuy in from management was identified as a challenge by interviewees 4 and 11. Both the interviewees expressed the view that convincing management to implement DevOps can be challenging.\n\nInterviewee 5 stated that writing custom scripts for automating tasks can be challenging. Interviewee 9 expressed that personnel may feel over-burdened with DevOps. He also pointed out that hidden complexities and hidden costs could occur in the later stages of adoption. Fear of measurement in employees was identified as another challenge. Interviewee 9 said, \"Measurement tools will log details like the number of hours a particular resource worked, number of lines of code he wrote. The progress of the developer will be recorded. So the developer might focus more on the progress, i.e. delivering something rather than being creative. Indirectly, he will be afraid of what the manager might think. Not everyone might be like that, but some people will. Also, with these tools, we can easily identify what is going wrong. This will increase stress level among employees.\"\n\nIntegration of different tools was specified as a challenge by interviewees 9 and 12. Interviewee 12 said, \"DevOps will need new workflows, so the existing workflows of the organization should be changed. For this, again the organization should invest in new tools. Another thing is companies will see tools as solutions to different problems. After getting a new tool, integrating it with the other existing tools will become a huge challenge.\"\n\nMigrating existing applications to cloud was specified as a challenge by interviewees 2 and 10. Interviewee 10 also added that not having proper resources to configure environments (production, testing) can cause the environments to fail. Interviewee 12 stated that fear of failure in managers can be challenging to DevOps adoption.\n\n### 4.4 Codes and Themes for RQ3\n\nA total of 19 codes for the solutions to overcome the challenges faced by organizations during DevOps adoption were identified from the 12 interview transcripts. The codes were selected based on the inclusion criteria relevance to study, and frequency of occurrence. The identified codes were categorized into the theme \"Solutions\". The Table 4.4 presents the codes and themes identified for RQ3.\n\n#### 4.4.1 Analysis of Interview Responses for RQ3\n\nIn this section, we analyse the codes related to the solutions to overcome the challenges faced while adopting DevOps in organizations. 18 codes were identified from the 12 interviews, and grouped into the theme \"Solutions\".\nChapter 4. Analysis of Interview Data\n\n<table>\n<thead>\n<tr>\n<th>Codes</th>\n<th>Code Inclusion Criteria</th>\n<th>Themes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Specify release criteria for each project</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Document all challenges</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Using a flexible system architecture</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Better to start DevOps in small projects</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Maintain an open communication channel</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Minimize handoffs using a good alignment of teams</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Maintain dashboards</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Include QA people</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Have a Proof of Concept (POC) in place</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Train people</td>\n<td>Frequency, Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Hire people with a DevOps mindset</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Clarify issues as soon as they arise</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Understanding of business requirements</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Document errors and their solutions</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Make decisions prior to the start of projects</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Having a proper management structure</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Conduct short meetings to encourage communication</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Estimate adoption costs and risks beforehand</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n<tr>\n<td>Use tools to bridge gap between old and new tools</td>\n<td>Relevance</td>\n<td>Solutions</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.4: Codes and Themes for RQ3\n\n**Solutions:** Interviewee 1 proposed specifying release criteria for each project as a solution. He added, \"I believe, in order to get into DevOps, we need to have a proper release criteria. Release criteria is used to determine when the code is ready to be pushed into production. For example, you may specify 70 percent unit test case coverage, 80 percent functional test case coverage as the release criteria for a backend code. It is different for each project. It cannot be defined in a book. Every project should have its own release criteria. The code should be rolled into production only if the release criteria is met.\" He also suggested that documenting the challenges that pop up in different projects can be helpful for future projects.\n\nInterviewee 2 proposed using a flexible system architecture. He said, \"For example, today we use AWS and if Amazon ups the price, then we will move to another cloud based architecture like google cloud. Again, this will have a different kind of architecture. We need to make sure that our architecture must be in such a way that if we need to move to any other service, we can do so without any big changes.\"\n\nInterviewee 3 suggested that it is better to start small. He added, \"You can’t just take a company that practices waterfall methodology, and start DevOps in it straight away.\"\nChapter 4. Analysis of Interview Data\n\nStart small. Smaller project is better. Small in terms of complexity and time.\"\n\nInterviewee 3 also suggested that using a good alignment of teams can minimize the handoffs. He also suggested that maintaining an open communication channel can help. He added, \"After forming a team, there should be norming of the team also. Everyone must get used to how everybody else works, and there should be an open communication channel so that everybody talks to each other.\" He also suggests maintaining dashboards. He states that teams should communicate about queues or backlogs present. He said, \"There should be a transparency of communication of the same information among all the team members. For that you can use dashboards. Everyone has to be able to see how many builds have failed or passed, how and why, etc.\"\n\nInterviewee 3 also proposed to include Quality Assurance (QA) people into DevOps teams. He said, \"Devops only talks about developer and operations. It is probably best to include QA people into that one. That way integration testing might still happen at the end, but at least there will be additional set of eyes looking at the test cases, making sure a holistic way of testing is done.\"\n\nInterviewee 4 suggested that having a Proof of Concept (POC) can help in getting buy in from managers and customers. He said, \"You just take some small component and apply DevOps to it, and showcase the effort you have put in, the amount of time you are saving, the stability of code, etc. Essentially explain that with one module and get them to buy in.\"\n\nInterviewees 5, 9 and 12 suggested that training people can help to reduce fear of change. Interviewee 6 suggested that hiring people with a DevOps mindset can help. He added, \"Look for those people who have the mindset of DevOps. They should be agile, have a mindset of doing automation, should be communicative.\"\n\nInterviewee 9 also suggested that clarifying issues as soon as they arise can help. He added, \"A single person cannot resolve issues at all levels, so more collaboration is required between team members.\"\n\nInterviewee 3 also suggested that documenting errors and their solutions can help. He commented that having proper error logs for listing errors, how and why they occurred, and how to prevent them from reoccurring can help.\n\nInterviewee 10 suggested that decisions should be made prior to the start of projects. He commented that changing decisions in the middle of the project could affect the environment.\nInterviewee 11 suggested having a proper management structure would help. He also stated that having proper communication channels can help whenever issues occur.\n\nInterviewee 12 suggested that conducting short meetings can encourage teams to share knowledge and ideas. He also suggested that estimating DevOps adoption costs and possible risks beforehand can help to reduce the fear of failure in managers. He added that based on the estimation, managers can determine whether or not to adopt it. He also proposed a solution to bridge the compatibility gap between tools. He said, \"There are some new tools like CloudShell and Helion CloudSystem that will bridge the compatibility gap between the old company tools and new cloud-based tools.\"\n\n### 4.5 Codes and Themes for RQ4\n\nA total of 11 codes for the practices that an organization needs to include while adopting DevOps were identified from the 12 interview transcripts. The codes were selected based on the inclusion criteria relevance to study, and frequency of occurrence. The identified codes were categorized into the themes \"Principles\" and \"Practices\". The Table 4.5 presents the codes and themes identified for RQ4.\n\n<table>\n<thead>\n<tr>\n<th>Codes</th>\n<th>Code Inclusion Criteria</th>\n<th>Themes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Automation</td>\n<td>Frequency, Relevance</td>\n<td>Principles</td>\n</tr>\n<tr>\n<td>Continuous Integration</td>\n<td>Frequency, Relevance</td>\n<td>Practices</td>\n</tr>\n<tr>\n<td>Continuous Deployment</td>\n<td>Frequency, Relevance</td>\n<td>Practices</td>\n</tr>\n<tr>\n<td>Continuous Testing</td>\n<td>Frequency, Relevance</td>\n<td>Practices</td>\n</tr>\n<tr>\n<td>Culture</td>\n<td>Frequency, Relevance</td>\n<td>Principles</td>\n</tr>\n<tr>\n<td>Collaboration</td>\n<td>Frequency, Relevance</td>\n<td>Principles</td>\n</tr>\n<tr>\n<td>Sharing</td>\n<td>Frequency, Relevance</td>\n<td>Principles</td>\n</tr>\n<tr>\n<td>Infrastructure as Code</td>\n<td>Relevance</td>\n<td>Principles</td>\n</tr>\n<tr>\n<td>Continuous Delivery</td>\n<td>Frequency, Relevance</td>\n<td>Practices</td>\n</tr>\n<tr>\n<td>Continuous Monitoring</td>\n<td>Frequency, Relevance</td>\n<td>Practices</td>\n</tr>\n<tr>\n<td>Continuous Feedback</td>\n<td>Frequency, Relevance</td>\n<td>Practices</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.5: Codes and Themes for RQ4\n\n### 4.5.1 Analysis of Interview Responses for RQ4\n\nIn this section, we analyse the codes related to the practices that an organization needs to include while adopting DevOps. 11 codes were identified from the 12 interviews, and grouped into the themes \"Principles\" and \"Practices\".\nChapter 4. Analysis of Interview Data\n\n**Principles:** Automation, Culture, Collaboration, Sharing and Infrastructure as a Code were identified as the principles of DevOps from the interviews.\n\nAutomation was identified as a principle of DevOps from all the interviews. Interviewee 2 commented that automation is a good thing about DevOps, as there is no manual intervention. Interviewee 8 said that automation makes tasks easier, and saves time. Interviewee 5 stated that automation is advantageous as it reduces chances of human error. Interviewee 6 commented that automation saves time and gives quick results. Interviewee 9 commented that minimal human intervention and maximum automation improves the delivery speed and quality. Interviewee 12 also stated that automation results in faster delivery.\n\nCulture was identified as another principle of DevOps from the interviews 8 and 11. Interviewee 8 commented that DevOps is more like a culture. He said that DevOps increases responsibility among all the teams involved. Interviewee 11 also shared a similar view. He commented that because DevOps is a culture, you don’t force it. He added that creation of conditions which break down the barriers between teams should be done from the management.\n\nCollaboration was identified as another DevOps principle from the interviews 2, 4, 9 and 12. Interviewee 4 said that \"DevOps is about collaboration between teams, and ensuring that the job gets done.\" Interviewee 9 commented that, \"There are several teams in the organization like development, business analysts, QA teams, testing teams and operations teams. If there is no proper collaboration between teams, what we deliver will be much different from what is expected by the customer.\" He added that DevOps increases collaboration by removing silos in the organization. Interviewee 2 also commented that DevOps breaks down silos. Interviewee 12 said, \"The main idea behind DevOps concept is collaboration between development and operations teams. There won’t be any walls between the teams, and everyone can see what is going on. Because of this visibility, collaboration will be enhanced and problems can be easily solved.\"\n\nSharing was identified as another principle of DevOps from interviews 11 and 12. Interviewee 11 commented, \"All the teams have to work together to figure out what needs to be done, to make sure all the changes are done in the right way.\" Interviewee 12 said, \"Sharing of ideas and knowledge is very important.\"\n\nInfrastructure as Code (IaC) was identified as another DevOps principle from interview 5. The interviewee stated that Infrastructure as Code (IaC) refers to writing code for automating tasks.\n\n**Practices:** Continuous Integration, Continuous Deployment, Continuous Testing, Continuous Delivery, Continuous Monitoring and Continuous Feedback were identified as the practices of DevOps from the interviews.\nContinuous Integration was identified as a DevOps practice from all the interviews. Interviewee 11 said, \"You have multiple people who want to change the same file, all at once. Which order should the changes go in? You can use Git source control tool for that. To collaborate with all team members. What happens when there is a conflict between one developer’s change and the next developer’s change? What should you do then? Things like code review. It all goes through source control. Things such as approvals. These things are very important to continuous integration. Continuous integration requires multiple people trying to change the same piece of software to integrate the changes with each other, and test them to make sure that all the different changes are not breaking one another.” Interviewee 3 commented, \"Before continuous integration, when a large project was going on, developers used to develop and push the code into their development channels and to promote from one channel to the other, it used to take a very long time. The Source Code Management (SCM) people used to gather all the latest changes from SCM tools, then they used to compile, and push it into the environment. To push it to the environment, SCM people had to collaborate with the infrastructure people because the environment has to be ready, and all the paths must be set, the databases must be set and so on. Continuous integration came into play because of these issues.\"\n\nContinuous Deployment was identified as another DevOps practice from all the interviews. Interviewee 11 commented \"The analogy of DevOps is, to break down the silos. A silo is a part of an organisation, where you have developers who do all the software development and software change, and then they throw it over the wall to the next silo the QA. So the testers, take what the developers have built and they do their thing. They are doing agile, right? And then the developers do their two week sprint and then deliver to QA. The QA then does their two weeks of testing. Then the developers start working on their next sprint and the QA start working on theirs, and then once the testers are finished with their work, they hand it over to the operations guys to deploy to production. And it just blows up. There are many reasons for this and the primary reason is the divisions of the people. So that organisational division, with the team division, work division, how things are set up are really destructive in terms of trying to deliver a working product or a working system. I will clarify that this is mainly for the internet based systems. Most stuff these days is mostly connected to the internet, internet technologies. So really we are talking about what can be seen in a web browser. So, as these ideas come around, the language starts to form and DevOps appears. The cloud revolution happened and the tools started coming around, and people using these tools realise there is a better way to do these things, and all of these aspects come together where the tools in place to build this thing called deployment pipeline. But in order to support that deployment pipeline, the technical things about how you get from a development environment to a test environment to a staging environment to a production environment, all those environments should look as similar as possible. So basically they should all try to look like production. They should have\nChapter 4. Analysis of Interview Data\n\nthe same type of configuration, application, same type of data, same OS, same kind of\nnetwork as possible, as much as reasonable.\"\n\nContinuous Testing was identified as a DevOps practice from all the interviews. In-\nterviewees 1, 2, 6, 7, 8 9, 10 and 12 commented that all test cases should be automated.\nInterviewees 2 and 7 added that they use Selenium tool for automating test cases in\ntheir organizations. Interviewee 4 said, \"We have implemented the Openstack infra-\nstructure development. The team basically works on the DevOps activities. We have\ntools like Jenkins, and the whole code is based on python. So, we have builds with\nrespect to python and every change that goes into the Git repository. Every change that\ngoes into the repository is hit by lot of test cases which are powered by a tool. So, we\nat the end of the day ensure that when a developer pushes a code to the repository, it\ngets checked at every phase. When a developer pushes a change sometimes, before the\ncode even gets landed into Git, they run certain prerequisite checks. It could be just the\ncompilation of the code, or it could be a unit test, or something else. Once that change\nhas been approved, the developers take a look at the changes and run tests which in-\nvolve full iteration or full system tests. Once those tests get approved, the change gets\npushed into the repository.\n\nContinuous Delivery was identified as another DevOps practice from all the interviews.\nInterviewee 11 commented, \"The DevOps part of continuous delivery is really about\nbringing the change management from all of the different organisational divisions, all\nthe way back to the start of the deployment pipeline. It is called a pipeline because,\nhow many directions does fluid flow in a pipeline? One. So here the fluid is the changes\nin the pipeline, and DevOps is the people. It is a cultural team. We build something,\ndouble check the pipeline, whether it is what it is supposed to be, test it, and verify\nbefore we deploy into production. So you have two things, DevOps and continuous\ndelivery. You cannot do one without the other. Customers ask me we want to deploy\ndaily, we want to deploy faster, with higher quality. If I want to do those things, I need\nDevOps. The technical things, how you set up a server, different tools etc., they are the\ney easy things. They do not work if the organisation is divided with different silos. You\nwill not be able to do continuous delivery, because you cannot bring all that change\nmanagement back to the start of the deployment pipeline. All these people; develop-\ners, QA and operations people have to work together to figure out what needs to be\ndone, to make sure all the changes are done in the right way, test it together. Different\npeople collaborate on the changes together on the same file, check the source code, in-\ntegrate the stuff and run it through continuous integration and deploy that change and\nshouldn’t have to change it at every stage of the deployment. It is the same chain that\nrepeats to get us through the deployment pipeline.\n\nContinuous Monitoring was identified as a DevOps practice from interviews 3, 9 and\n12. Interviewee 3 suggested that monitoring of performance metrics is a good practice.\nInterviewee 12 added that they enabled continuous monitoring in their organization.\nChapter 4. Analysis of Interview Data\n\nContinuous Feedback was identified as a DevOps practice from interviews 2, 9 and 12. Interviewee 2 commented that feedback is one of the best practices of DevOps. Interviewee 9 suggested that if companies release Minimum Viable Products (MVPs), the customers will give feedback about what they are expecting, what must be changed and so on. Based on the feedback, companies can improve the product, which will incrementally improve the value.\n\nAll the interviewees stated that there is no specific way of doing DevOps. Interviewee 2 commented \"To do DevOps, we need to be agile. DevOps is a framework of practices, and you should adopt them based on your needs.\" Interviewee 3 commented \"You can definitely use DevOps within any IT organization. All you you have to do is change management structure, change the culture, the thought process or the mindset.\" Interviewee 4 added, \"If an organization wants to adopt DevOps, they need to break the silos between each teams, and they should change their whole workflow. They need to sit down with the development team, QA team, build team, production or operations team and find out how they can streamline the entire release process. They need to figure out what would work well for all the teams, and follow that process.\" Interviewee 5 commented that \"We cannot just limit DevOps to only continuous integration or operations and development. It is a mindset which people should adopt to.\"\n\nInterviewee 8 commented, \"I think the definition of DevOps is not clear. Everyone has their own definition of Devops, every company has its own culture. It changes according to the company.\" Interviewee 9 suggested that based on the organizational structure, communication flow, and requirements, the organizations should develop a framework. He added that organizations do not have to include all the principles, just only what they need.\n\nInterviewee 12 added, \"DevOps is not just a defined process that you can simply implement. It is more like a mindset which will change the way different teams in the organization interact. In this case, the development and operations teams. With DevOps, there will be visibility on what is happening in the project to both the teams and they can collaborate easily. There is no specific way of doing this and we will adopt the different tools we need based on our project needs. What practices an organization should include will depend on the organization structure, requirements, its capabilities and project type.\"\n\n4.6 Codes and Themes for RQ5\n\nA total of 14 codes for the problems faced by DevOps teams during continuous integration, deployment and testing have been identified from the 12 interview transcripts. The codes were selected based on the inclusion criteria relevance to study, and fre-\nfrequency of occurrence. The identified codes were categorized into the theme \"Problems\". The Table 4.6 presents the codes and themes identified for RQ5.\n\n<table>\n<thead>\n<tr>\n<th>Codes</th>\n<th>Code Inclusion Criteria</th>\n<th>Themes</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Compatibility issues while integrating different tools</td>\n<td>Frequency, Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Testing environment flakiness</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Reverting from database changes</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Setting up infrastructure for the first time</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Production failures</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Teams might not be collocated</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Connectivity issues during integration</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Getting resources for solving workflow problems</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Lack of proper communication between teams</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Learning new technologies</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Having to manually check for application logs in Jenkins</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Accessibility</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Finding the right tools</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n<tr>\n<td>Time plans of projects might overlap</td>\n<td>Relevance</td>\n<td>Problems</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.6: Codes and Themes for RQ5\n\n4.6.1 Analysis of Interview Responses for RQ5\n\nIn this section, we analyse the codes related to the problems faced by DevOps teams during continuous integration, deployment and testing. 14 codes were identified from the 12 interviews, and grouped into the theme \"Problems\".\n\nProblems: Compatibility issues while integrating different tools was identified as a problem faced by DevOps teams from the interviews 9 and 12. Interviewee 12 commented, \"If the company’s legacy tools are not compatible with the new cloud-based tools then the DevOps teams must struggle.\"\n\nInterviewee 1 stated testing environment flakiness as a problem faced by DevOps teams. He explained, \"In continuous integration, when the developer writes a code, unit test cases should run. If all the unit test cases are green, then it should build the code. Let us say all the unit test cases should be passed in step 1, right? So every time I write code, the unit test coverage reduces because I am increasing the number of lines. In very few cases, you decrease the number of lines. But if I increase the number of lines, I may not add a unit test case. That means my unit test coverage comes down. Let us say earlier it was 60 percent. Now if I write 100 more lines of code, it comes down to 58 percent. So that means I should have another checkpoint over there, like my unit test coverage should be same or more than the previous build.\"\nInterviewee 2 stated that reverting from database changes could be a problem. \"If the database version changes, it could be a problem. When database changes are made, like SQL insert or delete any server, reverting is a challenge. In case you move to a container based model (like Docker), the biggest challenge is making the database changes.\"\n\nSetting up infrastructure for the first time was identified as a problem by interviewee 4. He commented, \"Setting up the continuous deployment infrastructure for the first time was challenging for us.\" Interviewee 3 stated that production failures can be a problem. He added, \"Reproducing production failures will be very difficult in DevOps, because your build has already gone, and narrowing down what build has caused production failure, going back and trying to replicate that in the lower environment is a huge challenge.\" He also stated that the DevOps teams may face problems if they are not collocated, due to lack of proper communication. Interviewee 5 stated that during integration, the teams might face connectivity issues to the server where they deploy the code.\n\nInterviewee 4 also stated that getting resources for solving workflow problems could be a problem. He commented, \"It is hard to get DevOps professionals. We have to get good engineers to solve problems with respect to the workflow. Finding the resources. It was one problem we faced.\"\n\nInterviewee 12 stated that lack of proper communication between teams could be a problem. He said, \"If the teams do not communicate properly, deployments will be pushed back or delayed for weeks or months.\" Interviewee 4 stated that learning new technologies is another problem DevOps teams face.\n\nInterviewee 5 said that having to manually check for application logs in Jenkins is a problem. He added, \"We deploy the code to the server using Jenkins. The custom jobs in Jenkins are written such that it will not show the logs of the server post deployment. It would only say the code is deployed successfully. We have manually login into the server and check for the application logs.\"\n\nAccessibility was stated as a problem by interviewee 7. He said, \"In our organization, deployment teams are still waiting for access to the servers.\" It is to be noted that the organization handles sensitive data.\n\nFinding the right tools was specified as a problem by interviewee 8. He said, \"We used to do unit tests and functional tests. We used to try TDD (Test Driven Development). The only problem we faced using unit test is we need to write functions we are using. The functional test is very tricky, they were randomly sailing and we had a question of what to use. So, we were using selenium and lettuce testing. Lettuce\nis a library in which we can write them like specific domain and specific language. Lettuce is very buggy, so we moved from lettuce. We then started using cucumber. The changes caused us some problems. So these are the problems we faced during functional testing; to find the suitable tool.\"\n\nInterviewee 9 stated that if time plans of projects overlap, it could be a problem. He said, \"They give you a 2-3 month time plan for a project, which contains details about the number of resources, and everything. Sometimes, you may complete the project before the expected 2 months. Sometimes, it may not be completed even after 3 months. There is a lot of difference between an idealistic plan and a realistic plan. If the manager comes up with a new plan for the project, that may overlap with other project time plans. Would you allocate resources to the new project or the old one? Would you shelve this existing project and take up a new one? How would you address these issues? You have to make a call. We face these kind of problems.\"\n\n4.7 Discussion\n\nA comprehensive discussion of the results obtained from the two qualitative research methods, interviews and SLR is provided in this section. The interview results are compared with the SLR results to validate them. Thus, the qualitative data will be validated and further used to obtain the quantitative data, which is the next step in the exploratory sequential design.\n\nIdentifying the benefits of implementing DevOps in organizations where agile development is in practice is an aim of this research. In addition to the benefits identified from the literature, the benefits identified from the interviews will also be included, and both results will be compared. The benefits identified from the literature are not specific to organizations which practice agile development in particular. Whereas, the benefits identified from the interviews are specific to organizations where agile development in practice. This is because in all the organizations of the interviewees, agile development was in practice prior to DevOps adoption. 20 benefits were identified from the interviews, and they were compared to those identified from the SLR. The benefits identified from both SLR and interviews are assigned individual IDs for reference. The final list of benefits after comparing and mapping the interview and SLR results is presented in the Table 4.7.\n\nThe benefits identified from both SLR and interviews were considered as the main benefits of implementing DevOps in organizations where agile development is in practice. The benefits identified from interviews are considered as the other important benefits, followed by those identified from SLR. Thus, increased collaboration between Dev and Ops teams, reduced time to market, faster feedback, reduced release cycle time, improved code quality, smooth and faster workflow, rapid product delivery, and easier implementation of business requirements were identified as the main benefits of\nimplementing DevOps in organizations where agile development is in practice. The other benefits were identified as empathy between Dev and Ops teams, breaking down of silos, easier tracking, detection of failures, increased system stability, automation, and minimal manual intervention.\n\nIdentifying the challenges faced by organizations while implementing DevOps is another aim of this research. In addition to the challenges identified from the literature, the challenges identified from the interviews will also be included, and both results will be compared. 20 challenges were identified from the interviews, and they were compared to those identified from the SLR. The challenges from SLR and interviews are assigned individual IDs for reference. The final list of challenges after comparing and mapping the interview and SLR results is presented in the Table 4.8. The chal-\n\n<table>\n<thead>\n<tr>\n<th>ID</th>\n<th>Benefits</th>\n<th>Source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>B1</td>\n<td>Increased collaboration between Dev and Ops teams</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>B2</td>\n<td>Frequent software releases</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B3</td>\n<td>Improved quality of software deployments</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B4</td>\n<td>Reduced time to market</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>B5</td>\n<td>Faster feedback</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>B6</td>\n<td>Reduced release cycle time</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>B7</td>\n<td>Empathy between Dev and Ops teams</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>B8</td>\n<td>Breaks down silos</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>B9</td>\n<td>Easier tracking</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>B10</td>\n<td>Easier detection of failures</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>B11</td>\n<td>Increased software reliability</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B12</td>\n<td>Improved code quality</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>B13</td>\n<td>Smooth and faster workflow</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>B14</td>\n<td>Increased system stability</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>B15</td>\n<td>Rapid product delivery</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>B16</td>\n<td>Increased customer satisfaction</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B17</td>\n<td>Increased overall organizational efficiency</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B18</td>\n<td>Increased responsiveness to business needs</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B19</td>\n<td>Balance between cost and quality</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B20</td>\n<td>Reduced need for rework</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B21</td>\n<td>Minimal manual intervention</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>B22</td>\n<td>Reduced communication overhead</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B23</td>\n<td>Increased predictability of software releases</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>B24</td>\n<td>Automation</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>B25</td>\n<td>Easier implementation of customer requirements</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>B26</td>\n<td>Increased revenue</td>\n<td>SLR</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.7: Benefits identified from SLR and Interviews\n### Table 4.8: Challenges identified from SLR and Interviews\n\n<table>\n<thead>\n<tr>\n<th>ID</th>\n<th>Challenges</th>\n<th>Source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>C1</td>\n<td>Lack of proper management structure</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>C2</td>\n<td>No proper training</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>C3</td>\n<td>Geographical distribution of Dev and Ops teams</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>C4</td>\n<td>Integrating new tools with existing company tools</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>C5</td>\n<td>Legacy software</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>C6</td>\n<td>Resistance from employees</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>C7</td>\n<td>Monolithic system architecture</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>C8</td>\n<td>Organizational structure</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>C9</td>\n<td>Hidden complexities and hidden costs</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C10</td>\n<td>Complexity due to multiple production environments</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>C11</td>\n<td>Designing software architectures to make them work with DevOps</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>C12</td>\n<td>Technical debt</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C13</td>\n<td>Buzzword perception</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>C14</td>\n<td>Unclear definition and goals of DevOps adoption</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>C15</td>\n<td>Security clearances</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C16</td>\n<td>Buy-in from senior management</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>C17</td>\n<td>Buy-in from customer</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>C18</td>\n<td>Fear of change</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>C19</td>\n<td>Fear of failure in managers</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C20</td>\n<td>Insufficient knowledge on applications and environments</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C21</td>\n<td>Making everyone accustomed to a new workflow</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C22</td>\n<td>Writing custom scripts for automating tasks</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C23</td>\n<td>Learning curve</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C24</td>\n<td>Lack of proper resources to configure environments</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C25</td>\n<td>Fear of measurement in employees</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>C26</td>\n<td>Culture and mindset of long timers</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>C27</td>\n<td>Limited visibility of production environments in embedded systems</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>C28</td>\n<td>Lack of proper automation tools in embedded systems domain</td>\n<td>SLR</td>\n</tr>\n</tbody>\n</table>\n\nChallenges identified from both SLR and interviews were considered as the most important challenges of DevOps adoption in organizations. The challenges identified from interviews were considered as the other important challenges, followed by those identified from SLR. No proper training for DevOps in organizations, geographical distribution of Dev and Ops teams, legacy software, resistance from employees, designing architectures to make them work with DevOps, buy-in from senior management, fear of change, culture and mindset of long timers are the most important challenges faced by organizations while adopting DevOps. Then, the tool adoption problems like integrating new tools with existing company tools, hidden complexities and costs, technical debt, fear of failure in managers, insufficient knowledge on applications and environ-\nments in case of outsourcing projects, making everyone accustomed to a new workflow, writing custom scripts for automating tasks, learning curve, security clearances, lack of proper resources to configure environments, and fear of measurement in employees are the other important challenges faced during DevOps adoption.\n\nSeveral new challenges to DevOps adoption were identified from the interviews. The reason behind obtaining different responses could be pertained to the different roles and organizations of interviewees. Thus, the responses should be validated using the quantitative research method, survey. The challenges will be included in the survey questionnaire, and assigned an ordinal scale to identify the importance level of each challenge. As the number respondents for survey will be higher than the interviewees, the results can be validated.\n\nIdentifying the solutions/mitigation strategies to overcome the DevOps adoption challenges is another objective of this research. There is no relevant literature to the solutions to overcome the DevOps adoption challenges, but the solutions were identified from the interviews. Thus, it was not possible to compare the interview findings with literature. The 18 solutions identified from the interviews are assigned individual IDs for reference, and are listed in the Table 4.9. Several solutions to overcome the adop-\n\n<table>\n<thead>\n<tr>\n<th>ID</th>\n<th>Solutions</th>\n<th>Source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>S1</td>\n<td>Specify release criteria for each project</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S2</td>\n<td>Document all challenges</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S3</td>\n<td>Using a flexible system architecture</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S4</td>\n<td>Better to start DevOps in small projects</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S5</td>\n<td>Maintain an open communication channel</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S6</td>\n<td>Minimize handoffs using a good alignment of teams</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S7</td>\n<td>Include QA people</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S8</td>\n<td>Have a Proof of Concept (POC) in place</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S9</td>\n<td>Train people</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S10</td>\n<td>Hire people with a DevOps mindset</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S11</td>\n<td>Clarify issues as soon as they arise</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S12</td>\n<td>Understanding of business requirements</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S13</td>\n<td>Document errors and their solutions</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S14</td>\n<td>Make decisions prior to the start of projects</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S15</td>\n<td>Having a proper management structure</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S16</td>\n<td>Conduct short meetings to encourage communication</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S17</td>\n<td>Estimate adoption costs and risks beforehand</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>S18</td>\n<td>Use tools to bridge gap between old and new tools</td>\n<td>Interviews</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.9: Solutions identified from Interviews\n\nsolution challenges were proposed by the interviewees. The online survey will be used to\nfurther validate the solutions, and identify any new solutions.\n\nIdentifying the practices that an organization should include for adopting DevOps is another aim of this research. Several practices (technical) were identified from the literature and interviews. In addition to the practices identified from the literature, the practices identified from the interviews will also be included, and both results will be compared. 6 practices were identified from the interviews, and they were compared to those identified from the SLR. The practices from SLR and interviews are assigned individual IDs for reference. The final list of practices after comparing and mapping the interview and SLR results is presented in the Table 4.10. The practices continuous inte-\n\n<table>\n<thead>\n<tr>\n<th>ID</th>\n<th>Practices</th>\n<th>Source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>P1</td>\n<td>Continuous Planning</td>\n<td>SLR</td>\n</tr>\n<tr>\n<td>P2</td>\n<td>Continuous Integration</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>P3</td>\n<td>Continuous Deployment</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>P4</td>\n<td>Continuous Testing</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>P5</td>\n<td>Continuous Delivery</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>P6</td>\n<td>Continuous Monitoring</td>\n<td>SLR, Interviews</td>\n</tr>\n<tr>\n<td>P7</td>\n<td>Continuous Feedback</td>\n<td>SLR, Interviews</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.10: Practices identified from SLR and Interviews\n\ntegration, deployment, testing, delivery, monitoring and feedback were identified from both SLR and interviews, while continuous planning was identified from the SLR. The practices will be further validated using survey.\n\nIt was noted that DevOps teams face several problems during the continuous activities of DevOps like continuous integration, deployment and testing. There is no literature related to the problems faced by DevOps teams, but the problems were identified from the interviews. It was hence not possible to compare the interview findings with literature. The 14 problems identified from the interviews are assigned individual IDs for reference, and are listed in the Table 4.11.\nChapter 4. Analysis of Interview Data\n\n<table>\n<thead>\n<tr>\n<th>ID</th>\n<th>Problems</th>\n<th>Source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Pb1</td>\n<td>Compatibility issues while integrating different tools</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb2</td>\n<td>Testing environment flakiness</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb3</td>\n<td>Reverting from database changes</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb4</td>\n<td>Setting up infrastructure for the first time</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb5</td>\n<td>Production failures</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb6</td>\n<td>Teams might not be collocated</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb7</td>\n<td>Connectivity issues during integration</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb8</td>\n<td>Getting resources for solving workflow problems</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb9</td>\n<td>Lack of proper communication between teams</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb10</td>\n<td>Learning new technologies</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb11</td>\n<td>Having to manually check for application logs in Jenkins</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb12</td>\n<td>Accessibility</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb13</td>\n<td>Finding the right tools</td>\n<td>Interviews</td>\n</tr>\n<tr>\n<td>Pb14</td>\n<td>Time plans of projects might overlap</td>\n<td>Interviews</td>\n</tr>\n</tbody>\n</table>\n\nTable 4.11: Problems identified from the Interviews\n\nSeveral problems faced by DevOps teams during continuous integration, deployment and testing were specified by the interviewees. The online survey will be used to further validate the problems, and identify any new problems.\n\n4.8 Threats to Validity\n\nThe threats to validity for the interviews are presented in this section.\n\n1) Internal Validity:\nThe internal validity threats to the interview data could be related to the selection of interviewees, design of the interview questionnaire, and incorrect interpretation of the collected data. To mitigate the threat of selection of interviewees, the target population was defined as software engineering practitioners that have worked with DevOps. Convenience sampling was done to select the interviewees. Some personal contacts who are working with DevOps were selected as the interviewees, and DevOps practitioners identified using LinkedIn were chosen. To mitigate the threat of the design of interview questionnaire, a semi-structured interview questionnaire having both open-ended and close-ended questions was designed based on the SLR findings. The questions were designed to be easily understandable, and continuously improvised by taking feedback from the supervisor. Questions related to the demographics of interviewees, and the present study were included. Semi-structured questionnaire was designed as it facilitates more interaction. All the 12 interviewees were asked the same set of questions, and new questions were spontaneously framed and asked whenever needed. The interviewees were promised complete confidentiality to obtain genuine and valid answers.\nChapter 4. Analysis of Interview Data\n\nTo mitigate the threat of incorrect interpretation of collected data due to researcher bias, audio recording was done in all interviews after taking permission from the interviewees. The data transcription was manually done without leaving out any sentence. Thematic coding was done to analyse the collected data. All transcripts were thoroughly read to familiarize with the data. Codes in each transcript were identified by manually examining the transcripts. Each code was highlighted with a different colour, based on the question, and categorized into themes based on the code inclusion criteria, frequency and relevance.\n\n2) Construct Validity:\nThe construct validity threat to the interview data is related to the interview questionnaire not being able to obtain the aims and objectives of the research. To mitigate this threat, the questionnaire was designed based on the SLR findings. It was designed in the simplest way possible, to ensure understandability. Also, feedback from the supervisor was taken, and the questionnaire was continuously improved according to the feedback. The interviewees were also asked if the questions were understandable or not after completing the interviews, to ensure understandability of the questionnaire.\n\n3) External Validity:\nThe external validity threat is related to the generalizability of the results. To mitigate this threat, interviewees having different roles and different experience were chosen. Also, it was ensured that no more than two people from the same organization were interviewed. Thus, we tried to make the results generalizable.\nChapter 5\n\nAnalysis of Survey Questionnaire Results\n\nIn this chapter, the data analysis and results of the online survey are described.\n\nThe steps followed for conducting the survey were defining the survey objectives, planning the survey, identifying the target population and sampling, creating the online questionnaire, validating the questionnaire, sending the questionnaire to respondents, collecting data and analysing the data [41]. Initially, the survey objectives were identified from the research questions. The objectives of the survey are\n\n- To identify the benefits of implementing DevOps in organizations where agile development is in practice\n- To identify the challenges faced by the organizations while adopting DevOps\n- To identify the solutions to overcome the adoption challenges\n- To identify the practices of DevOps that an organization must include while adopting DevOps\n- To identify the problems faced by DevOps teams during continuous integration, deployment and testing\n- To identify whether the results obtained from the SLR and interviews can be generalized to a larger population sample\n\nBased on the survey objectives, the planning of survey was done. The survey was scheduled for a period of four weeks because of the time constraint.\n\n5.1 Target Population and Sampling\n\nThe target population should be defined to obtain a sample [41]. The target population is the group or individuals who can answer the survey. For our research, the target population is software engineering practitioners that have worked with DevOps. Shull et al [41] note that \"a valid sample is a representative subset of the target population\".\n\nThere are probabilistic and non-probabilistic sampling methods. For our study, non-probabilistic sampling was employed for choosing the survey respondents. As the\nThe target population is specific and limited, it is hard to rely on a random sample. We followed two non-probabilistic sampling methods for selecting the survey respondents, convenience sampling and snowball sampling. Convenience sampling refers to gathering responses from people who are available and willing to respond [41]. Snowball sampling refers to asking people who have answered the survey to recommend the survey other people who they think would answer it [41]. First, the population sample was selected from personal contacts, and practitioners from LinkedIn and Facebook. It was ensured that the population sample for survey is different from the interview respondents to get valid data. The link to the survey was posted in several online forums and groups related to DevOps on LinkedIn and Facebook. Additionally, the respondents were requested to forward the survey to their contacts who could answer it.\n\n5.2 Designing the Survey Questionnaire\n\nThe survey questionnaire was designed based on the objectives, with both open-ended and closed questions. The questions were related to the demographics of the respondents, and the present study. The questionnaire was prepared using Google docs. The responses were stored in an excel sheet, which facilitated easier data analysis. The questions related to demographics include the type of organization, geographical location of the organization, size of the organization, role of the respondent in the organization, years of work experience of the respondent, and years of the respondent’s experience with DevOps.\n\nThe questions related to the benefits of implementing DevOps in organizations include an open-ended question about the development methodology followed in the organization before adopting DevOps, a closed question about the benefits of implementing DevOps in organizations, which has options from which the respondents can choose. The benefits identified from both SLR and interviews were added as the options. The question was designed so that the respondents can select more than one option. Open-ended questions were also provided for the respondents to list out any other benefits of adopting DevOps.\n\nThe questions related to the challenges faced by organizations while adopting DevOps include a closed question which has the challenges identified from SLR and interviews listed as the options, and open-ended questions to identify any other challenges. In the closed question, each challenge was assigned an ordinal scale to identify the level of importance, with the options very challenging, challenging, somewhat challenging, not challenging and cannot specify. Another closed question was also included to identify whether DevOps adoption can be challenging for organizations that are implementing it for the first time. It was accompanied with an ordinal scale with the options strongly disagree, disagree, neither agree nor disagree, agree and strongly agree.\nChapter 5. Analysis of Survey Questionnaire Results\n\nThe questions related to the solutions to overcome the adoption challenges include a closed question which has the solutions identified from the interviews as the options. Open-ended questions were also included to identify any other solutions to overcome the adoption challenges.\n\nA closed question with the practices of DevOps identified from SLR and interviews listed as the options, and open-ended questions to identify any other practices that an organization needs to include for adopting DevOps were included.\n\nThe questions related to the problems faced by DevOps teams during continuous integration, deployment and testing include a closed question with the problems identified from the interviews as the options, and open-ended questions to identify any other problems that DevOps teams face.\n\nAll the questions related to demographics and the study were marked as required to ensure complete responses. A text box was added at the end of the survey for the respondents to fill in their names and email ids, if they wanted to receive a compilation of the survey results.\n\n5.3 Survey Questionnaire Validation\n\nThe survey questionnaire was validated to ensure the reliability of the questionnaire, and that the questions were clear and understandable. This way of evaluating the questionnaire is also called pre-testing [41]. The survey questionnaire was reviewed by the supervisor, and changes were made according to his feedback. After that, a pilot study of the survey was conducted. Pilot surveys are conducted by sending the questionnaire to a small sample. Pilot surveys can identify any problems with the questionnaire, determine the response rate, and also help in assessing the reliability of the questionnaire [41].\n\nThe pilot study was conducted on three software engineering practitioners that have worked with DevOps to ensure that the questions were understandable, and also to calculate the approximate time taken to answer the questionnaire. The criteria for validating the questionnaire was: understandability of the questions and options, questionnaire length and time taken for completing the survey. 25 questions were included in the questionnaire. All the three respondents commented that the questionnaire was understandable, and that it took around 10-15 minutes to answer it. Thus, the questionnaire was validated. After the pilot study, the respondents felt that some options seemed repetitive/unnecessary. Such options were excluded.\n\nAfter validating the questionnaire, it was sent to the population sample via emails and social networking sites. The link to the survey was also posted in several online\nforums and social networking groups related to DevOps. To motivate the respondents to provide complete and accurate answers, a statement explaining the purpose of the research and its relevance to the respondents, importance of their responses, maximum time taken for answering the survey, and ensuring the anonymity of respondents was added to the questionnaire. 50 complete responses were obtained for the survey.\n\nThe questionnaire was prepared using google docs because it is free, and the responses are directly stored in an excel spreadsheet. Also, the spreadsheet is shareable. Both the researchers can access and edit the form and the results at the same time.\n\n5.4 Results of the Survey\n\n5.4.1 Analysis of the Demographics of the Respondents\n\nThe respondents were asked to mention their geographical location in the survey. Respondents from 15 countries have participated in the survey. Of them, most of the participants are from India (30%), USA (22%) and Sweden (16%). The list of other countries includes UK (6%), Israel (4%), Norway (4%), Germany (2%), Ireland (2%), Australia (2%), Uruguay (2%), Brazil (2%), Netherlands (2%), Poland (2%), Finland (2%) and Nigeria (2%). The geographical location of the 50 respondents is presented in the following figure.\n\n\n\nFigure 5.1: Geographical Location of Respondents\nChapter 5. Analysis of Survey Questionnaire Results\n\nAs the target population is software engineering practitioners that have worked with DevOps, the respondents were also asked to mention their role in the organization. The respondents had several roles, DevOps Consultant (14%), Network Engineer (6%), DevOps Engineer (22%), DevOps architect (4%), System Developer (2%), DevOps Configuration/Release Manager (2%), DevOps developer (2%), DevOps delivery lead (6%), ALM/DevOps practitioner (2%), IT Architect (4%), SSME (2%), Build and Release Engineer (2%), Technical lead (4%), Continuous delivery engineer (2%), IT Director (4%), Architect/Developer (2%), IT Manager/DevOps (10%), Lead Developer (2%), Lead DevOps (2%), Principal Architect/Cloud & DevOps (2%), Senior Software Engineer (2%). The roles of the respondents are presented in the following table.\n\n<table>\n<thead>\n<tr>\n<th>Roles</th>\n<th>Frequency</th>\n<th>Percentage of Responses</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>DevOps Consultant</td>\n<td>7</td>\n<td>14</td>\n</tr>\n<tr>\n<td>Network Engineer</td>\n<td>3</td>\n<td>6</td>\n</tr>\n<tr>\n<td>DevOps Engineer</td>\n<td>11</td>\n<td>22</td>\n</tr>\n<tr>\n<td>DevOps Architect</td>\n<td>2</td>\n<td>4</td>\n</tr>\n<tr>\n<td>System Developer</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>System Engineer</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>DevOps Configuration/Release Manager</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>DevOps Developer</td>\n<td>3</td>\n<td>6</td>\n</tr>\n<tr>\n<td>DevOps Delivery Lead</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>ALM/DevOps Practitioner</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>IT Architect</td>\n<td>2</td>\n<td>4</td>\n</tr>\n<tr>\n<td>SSME</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>Build and Release Engineer</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>Technical Lead</td>\n<td>2</td>\n<td>4</td>\n</tr>\n<tr>\n<td>Continuous Delivery Engineer</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>IT Director</td>\n<td>2</td>\n<td>4</td>\n</tr>\n<tr>\n<td>Architect/Developer</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>IT Manager/DevOps</td>\n<td>5</td>\n<td>10</td>\n</tr>\n<tr>\n<td>Lead Developer</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>Lead DevOps</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>Principal Architect/Cloud & DevOps</td>\n<td>1</td>\n<td>2</td>\n</tr>\n<tr>\n<td>Senior Software Engineer</td>\n<td>1</td>\n<td>2</td>\n</tr>\n</tbody>\n</table>\n\nTable 5.1: Roles of the Respondents\n\nThe respondents were also asked to mention the size of the organizations, in terms of number of people. It was seen that most of the respondents come from organizations with size greater than 5000 (38%). The other respondents come from organizations with size 50-500 (22%), followed by 500-5000 (20%), 10-50 (12%), and less than 10 (8%). The size of organizations of respondents is presented in the following figure.\nChapter 5. Analysis of Survey Questionnaire Results\n\nThe respondents were also asked to mention their overall work experience, in number of years. Most of the respondents have 4-9 years (30%), 10-15 years (30%) and 15-20 years (22%). The other respondents have greater than 20 years (10%) and less than 3 years (8%). The work experience of the respondents is presented in the following figure.\n\nAs our research focuses on the adoption of DevOps in organizations, the respondents should have knowledge on DevOps, which makes their experience with DevOps an important factor to be considered. Thus, the respondents were also asked to mention the number of years of experience in working with DevOps. It was seen that most of\nthe respondents have 1-2.5 years (44%) and 2.5-4 years (36%). The other respondents have more than 4 years (20%) of experience with DevOps. The experience with DevOps of all the respondents is presented in the following figure.\n\n\n\nAlso, the respondents were asked to mention the development methodology followed in their organizations before adopting DevOps. Most of the respondents answered that they followed Agile methodologies (72%) and hybrid methodologies (22%). The other respondents answered that they followed plan-driven methodologies (6%). The methodologies followed in the respondents’ organizations are presented in the following figure.\n\n\n5.4.2 Benefits of Implementing DevOps in Organizations\n\nOne of the objectives of this research is to identify the benefits of implementing DevOps in organizations where agile development is in practice. Thus, the respondents were asked to identify the benefits which they know can be achieved after implementing DevOps in organizations. The benefits identified from SLR and interviews were included, and the respondents had to choose from those options. Additionally, they were also asked to specify any additional benefits of adopting DevOps, which were not listed in the options.\n\nFrom the responses, it was seen that 84% of the respondents (42) identified increased collaboration between Dev and Ops teams as a benefit. Frequent software releases was identified as a benefit by 84% of respondents (42). 78% of respondents (39) identified improved quality of software deployments as a benefit. Reduced time to market was identified by 74% of respondents (37). Faster feedback was identified by 72% of respondents (36) and reduced release cycle time was identified by 70% of respondents (35). The other benefits were identified as empathy between Dev and Ops teams, breaking down silos, easier tracking, easier detection of failures, increased software reliability, improved code quality, smooth and faster workflow, increased system stability, rapid product delivery, increased customer satisfaction, increased overall organizational efficiency, and increased responsiveness to business needs by 48-58% of the respondents. 38% of respondents (19) identified balance between cost and quality as a benefit. Reduced need for rework was identified as a benefit by 40% of respondents (20). Minimal manual intervention was identified by 34% of respondents (17). Reduced communication overhead was identified as a benefit by 34% of respondents (17). 32% (16) identified increased predictability of software releases as a benefit, and 32% (16) identified automation as a benefit. Only 28% of respondents (14) identified easier implementation of customer requirements as a benefit. Only 24% of respondents (12) identified increased revenue as a benefit.\n\nThe following figure provides the benefits of implementing DevOps in organizations, as identified by the respondents.\n5.4.3 Challenges faced by Organizations while adopting DevOps\n\nAnother objective of this research is to identify the challenges faced by organizations while adopting DevOps. The respondents were asked whether DevOps adoption can be challenging for organizations that are implementing it for the first time. They were given an ordinal scale of options, strongly disagree, disagree, neither agree nor disagree, agree and strongly agree. Also, the respondents were asked to identify which challenges can be faced by organizations while adopting DevOps. The challenges identified from SLR and interviews were listed as the options. They were also asked to specify the level of difficulty for each challenge by providing an ordinal scale with the options very challenging, challenging, somewhat challenging, not challenging and cannot specify.\n\nThe following figure presents the challenges faced by organizations while adopting DevOps, and their level of difficulty as specified by the respondents.\nFigure 5.7: DevOps adoption Challenges\n\nThe responses are presented as heat maps. The heat maps show the number of responses obtained for each challenge, with respect to its level of difficulty. The highest values are assigned a dark colour, and the least values are assigned a light colour. From the figure, it can be seen that legacy software and culture and mindset of long timers are very challenging for organizations adopting DevOps. Also, lack of proper management structure, no proper training, integrating new tools with existing company tools, resistance from employees, organizational structure, hidden complexities and costs, complexity due to multiple production environments, designing architectures to make them work with DevOps, and technical debt can be challenging for organizations.\nChapter 5. Analysis of Survey Questionnaire Results\n\nTechnical debt, security clearances, buy-in from management and customers, insufficient knowledge on applications and environments, making everyone accustomed to a new workflow, learning curve can be challenging for organizations adopting DevOps. Lack of proper resources to configure environments, limited visibility of production environments and lack of automation tools in embedded systems domain are challenging for organizations.\n\nIt can be seen that geographical distribution of Dev and Ops teams, buzzword perception, unclear definition and goals of DevOps adoption, fear of failure in managers, writing custom scripts for automating tasks, and fear of measurement in employees are not very challenging.\n\n5.4.4 Solutions to overcome the Challenges faced during DevOps adoption\n\nIdentifying the solutions to overcome the challenges faced by organizations during DevOps adoption is another aim of this research. Thus, the respondents were asked to identify the solutions to overcome DevOps adoption challenges. The solutions identified from interviews were listed as the options. Additionally, they were also asked to specify any additional solutions to overcome the DevOps adoption challenges, which were not listed in the options.\n\n88% of respondents (44) specified that it is better to start DevOps in small projects. 68% of respondents (34) identified conducting short meetings to encourage communication between teams as a solution. Proper training of employees was identified as a solution by 64% of respondents (32). Clarifying issues that arise as soon as possible was identified by 56% of respondents (28). 56% of respondents (28) identified hiring people with a DevOps mindset as a solution. 54% of respondents (27) identified using a flexible architecture as a solution. 52% of respondents (26) identified providing a better understanding of business requirements to every employee as a solution. 52% of respondents (26) identified having a proper management structure as a solution. 46% of respondents (23) identified having a Proof of Concept (PoC) in place as a solution. 42% of respondents (21) identified having a Proof of Concept (PoC) in place as a solution.\n\n42% of respondents (21) specified to minimize hand-offs using an open communication channel, and a good alignment of teams. 42% of respondents (21) identified specifying release criteria for each project, and documenting the challenges as a solution. 40% of respondents (20) identified documenting errors and their solutions. 38% of respondents (19) specified to estimate adoption costs and risks before adopting DevOps. 36% of respondents (18) identified including QA people as a solution. 14% of respondents (7) identified making decisions prior to start of projects as a solution. Only 12% of respondents (6) identified using tools like CloudShell and Helion CloudSystem for bridging the compatibility gap between legacy tools and the new cloud-based tools.\nChapter 5. Analysis of Survey Questionnaire Results\n\nas a solution.\n\nThe following figure presents the solutions to overcome the DevOps adoption challenges, as specified by the respondents.\n\nFigure 5.8: Solutions to overcome the DevOps adoption Challenges\n\n5.4.5 Practices to be included by organizations for adopting DevOps\n\nAnother aim of this research is to identify the practices that an organization must include for adopting DevOps. Thus, the respondents were asked to identify the practices to be included by organizations. The practices identified from SLR and interviews are listed as the options. Also, the respondents were asked to specify any other practices which were not listed in the options.\n\n94% (47) of respondents identified continuous integration as a practice. 88% of respondents (44) identified continuous testing as a practice. Continuous delivery was identified as a practice by 86% of respondents (43). Continuous deployment was identified as a practice by 84% of respondents (42). 76% of respondents (38) identified continuous monitoring as a practice. Continuous feedback was identified as a practice by 60% of respondents (30). Continuous planning was identified as a practice by 58% of respondents (29). We refer to continuous integration as CI, continuous deployment as CD and continuous testing as CT.\nChapter 5. Analysis of Survey Questionnaire Results\n\nThe following figure presents the practices to be included by organizations while adopting DevOps, as identified by the respondents.\n\n![DevOps Practices Chart]\n\n---\n\n### 5.4.6 Problems faced by DevOps Teams during Continuous Integration, Deployment and Testing\n\nAnother objective of this research is to identify the problems that DevOps teams face during continuous integration, deployment and testing. Thus, the respondents were asked to identify the problems faced by DevOps teams during continuous integration, deployment and testing. The problems identified from the interviews were listed as the options. Also, the respondents were asked to specify any other problems faced by DevOps teams, which were not listed in the options.\n\n- 76% of respondents (38) identified configuring infrastructure for the first time as a problem.\n- 74% of respondents (37) identified tool-related issues as a problem.\n- 70% (35) of respondents identified production failures as a problem.\n- 60% of respondents (30) identified learning new technologies as a problem.\n- 56% of respondents (28) identified lack of proper communication between teams as a problem.\n- 52% of respondents (26) identified testing environment flakiness as a problem.\n- 50% of respondents (25) identified connectivity issues during integration as a problem.\n- 44% of respondents (22) identified reverting from database changes as a problem.\n- 40% of respondents (20) identified getting resources for solving problems related to workflow as a problem.\n- 32% of respondents (16) identified lack of collocated teams as a problem.\n- 28%\nof respondents (14) identified overlapping time plans of different projects as a problem. 24% of respondents (12) identified accessibility as a problem. Only 12% of respondents (6) identified having to manually check for application logs in Jenkins as a problem.\n\nThe following figure presents the problems faced by DevOps teams during continuous integration, deployment and testing, as specified by the respondents.\n\n\n\nFigure 5.10: Problems faced by DevOps teams during CI, CD and CT\n\n5.4.7 Results of the Open-ended Questions\n\nIn addition to the closed questions, open-ended questions were also included in the questionnaire so that the respondents can provide additional information, which was not listed in the options. The open-ended questions were included for the benefits of adopting DevOps, challenges faced by organizations during DevOps adoption, solutions to overcome the challenges, practices of DevOps, and the problems faced by DevOps teams during continuous integration, deployment, and testing. In this section, the results of the open-ended questions are elucidated. Thematic coding was done to analyse the responses obtained to the open-ended questions. Different answers were obtained for each question, and only the frequently stated terms were identified and coded. The code inclusion criteria was specified as frequency of occurrence.\n\nThe respondents were asked to specify the benefits of adopting DevOps, which were\nChapter 5. Analysis of Survey Questionnaire Results\n\nnot listed in the options of the closed question. Some respondents have specified new benefits, while some respondents commented that the benefits were mostly covered in the closed question options. For example, one respondent commented, \"Transparency, clarity and visibility on team members actions which enables to differentiate between stars and slackers.\"\n\nAnother respondent commented, \"Improving IT reputation within the business after countless failed IT project with the waterfall method.\"\n\nAnother respondent commented, \"End of blame game. Developers better understanding the Operations related challenges and vice versa.\"\n\nAmong all the responses, only the mostly stated benefits are included. The benefits identified are:\n\n- Less stressful and faster deployments.\n- Customer and employee satisfaction.\n- Lesser roll backs.\n- Better performance of both people and systems.\n- Budget control.\n- Faster resolution of problems.\n- More stable operating environments.\n- Advantage over rival companies that do not do DevOps.\n- Minimized deployment related downtime.\n\nThe respondents were asked to specify the challenges faced while adopting DevOps, which were not listed in the options of the closed question. Some respondents have specified new challenges, while some respondents commented that the challenges were mostly covered in the closed question options.\n\nOne respondent commented, \"With DevOps the line of responsibility becomes blurred, which can be confusing in the beginning.\"\n\nAnother respondent commented, \"Mindset change; Devs and Ops have traditionally been separated, and it takes some time and strong and committed leadership to bring them out of their comfort zones.\"\n\nAnother respondent commented, \"Not just buy-in from customer/management alone, but a good grass roots company wide culture is needed for successful adoption of DevOps.\"\nAnother respondent commented, \"Investment for transformation, and waiting till ROI is realised.\"\n\nAnother respondent commented, \"Picture this. A lot of engineers and consultants have just finished acquiring Agile practices and some organisations have not even adopted them completely. DevOps comes along and now Agile teams become DevOps teams. Lot of resistance from employees to learn due to fear of failure. Not many brave team members put forward for DevOps POCs.\"\n\nAmong all the responses, only the mostly stated challenges are included. The challenges identified are:\n\n- Unawareness of right tools for doing tasks.\n- Insufficient knowledge on how to change/simplify current architecture to suit better into modern time automated environment.\n- Finding the right and experienced personnel.\n\nThe respondents were asked to specify the solutions to overcome the challenges faced while adopting DevOps, which were not listed in the options of the closed question. Some respondents have specified new solutions, while some respondents commented that the solutions were mostly covered in the closed question options.\n\nOne respondent commented, \"Have ‘internships’ between Dev and Ops teams. Ops should adopt the best practices from the Devs, e.g., test-driven development and pair-programming. Devs should learn about the challenges of running the software in the real-world where things often go wrong.\"\n\nAnother respondent commented, \"Have representative of Dev in Ops and vice versa to influence the software architecture as well as operation aspect of the software.\"\n\nAnother respondent commented, \"Cultural training to increase ownership from all teams on all issues. It isn’t your problem, it is our problem.\"\n\nAnother respondent commented, \"Start small, preferably 1 or max 2 teams with adopting DevOps. Then scale up to 3 or 4 and keep on going like an oil stain.\"\n\nAmong all the responses, only the mostly stated solutions are included. The solutions identified are:\n\n- Encourage bonding of people and breaking down of silos.\n- Communication is basic.\n- Start small.\n- Training and hiring those who possess a greater degree of empathy.\nThe respondents were asked to specify the practices that organizations must include while adopting DevOps, which were not listed in the options of the closed question. Some respondents have specified new practices, while some respondents commented that the practices were mostly covered in the closed question options.\n\nOne respondent commented, \"Continuous communication and collaboration. DevOps is more than Dev and operations, it involves everyone in the team.\"\n\nAnother respondent commented, \"Remember DevOps is not just about technical practices. Culture and communication is also very important.\"\n\nAmong all the responses, only the mostly stated practices are included. It was seen that the respondents only specified the non-technical practices, i.e. the DevOps principles. They are:\n\n- Infrastructure as Code.\n- Automation.\n- Collaboration.\n- Culture.\n- Sharing.\n\nThe respondents were asked to specify the problems faced by DevOps teams during continuous integration, deployment and testing, which were not listed in the options of the closed question. Some respondents have specified new problems, while some respondents commented that the problems were mostly covered in the closed question options.\n\nOne respondent commented, \"Often operations do not understand developers’ problems, and sometimes even the nomenclature, and vice versa. There are often easier ways to integrate and test the software but it requires some architecture changes in the software.\"\n\nAnother respondent commented, \"Every system may include industry standard tools and methods, but every architecture is unique and distinct, which makes tackling issues very tough for those new to a given architecture.\"\n\nAmong all the responses, only the mostly stated problems are included. The problems identified are:\n\n- Entrenched differences/ antagonism between teams.\n- There are many number of tools available in market, picking up the right tools is challenging for DevOps teams.\nChapter 5. Analysis of Survey Questionnaire Results\n\n- Changing and complex software architectures.\n- Undocumented legacy systems with no enough knowledge.\n- Lack of ownership by various teams.\n- Getting support for open source tools.\n\n5.5 Threats to Validity\n\nBasing on the study by Wohlin [55], the possible threats for survey which affect the execution of the research are identified and are listed. They are:\n\n1) Internal Validity:\nInternal validity is the threat related to the survey questionnaire, questions provided in the survey and the data equipped to answer those questions for the responses. These threats occur when the respondents do not find any particular question understandable, or could not answer the question because they feel the options are inappropriate, or not comfortable with the survey questionnaire. To mitigate these threats, the survey has been designed to be easily understandable. If the respondent did not find any suitable options within the question, an open-ended question \"Please specify any other benefits/challenges/solutions/practices/problems which are not listed in the question\" is provided, so that the respondents can conveniently answer in it. In addition to the closed question responses, the responses provided in the open ended question i.e., \"Please specify any other which are not listed in the question\" are also considered.\n\n2) External Validity:\nExternal validity is the risk regarding the target population of the survey. There is a risk involved in this area because the authors need to look for the people who are either practising, or practised DevOps. There are not many people familiar with this concept. So, looking for the people can be a problem. To mitigate this, the authors have posted the link through Facebook and LinkedIn in the groups related to DevOps. The authors have also sent the link to the DevOps practitioners in person to make sure that the survey is answered by the eligible respondents. The groups have DevOps practitioners all over the world and the particular respondents were chosen based on their LinkedIn profile information, and through personal contacts. The analysis and the information obtained from the survey can be inaccurate if the respondents are not familiar with the concept. These threats are mitigated carefully by choosing the eligible respondents, which enabled the authors to rely on the answers given by the respondents.\n\n3) Construct Validity:\nConstruct Validity is the threat that occurs when the authors have not correctly interpreted the purpose of the questionnaire, or prepare questions that are irrelevant to the literature, or the questions provided do not add any information to the research. This\nthreat was mitigated by analysing the information obtained through SLR and the interviews, and formulating the survey questionnaire based on that information. The SLR and interview responses were mapped, as listing out several individual options may expand the length of the survey, which later affects the survey quality. The responses obtained from both SLR and interviews were mapped, and the options were provided in a simple way so that the respondents can understand them easily. The questions were framed in the survey in accordance to the research questions and objectives. A pilot study of the survey was conducted before sending it to the respondents. The survey was submitted to three respondents for the pilot study, and review from those respondents was taken. This helped the authors in assessing the understandability and the readiness of the survey.\n\n4) Conclusion Validity:\nConclusion validity is the threat related to the trustiness, usefulness and quality of the results obtained from the survey. To mitigate this threat, the results obtained were analysed carefully and interpreted using heat maps and descriptive statistics. Using heat maps, the individual responses for each question can be observed. By including the mostly stated responses, the authors have carefully analysed the results of the open ended questions. The descriptive statistical analysis is used in considering the results obtained. With this analysis, the differences in between the responses are observed, and it is seen that they have occurred due to different roles of the respondents, and the differences in experience.\nChapter 6\n\nDiscussion\n\nIn this section, the results obtained from the mixed methods approach are used for answering the research questions. The results obtained from the qualitative and quantitative methods are mapped and presented along with the research questions.\n\n6.1 Answering the RQs\n\nRQ1: How does implementing DevOps in the organizations where agile is in practice help them?\n\nThe aim of this research question is to look into the benefits of adopting DevOps in organizations where agile development is in practice. The perceived benefits have a crucial role in determining whether or not to implement DevOps in an organization. The perceived benefits of adopting DevOps in organizations in general were identified from the literature, and also the actual benefits achieved in practice by organizations were identified from the interviews and survey. Agile development was in practice prior to DevOps adoption in all organizations of the interviewees. Whereas, agile and hybrid methodologies were in practice in organizations of 47 survey respondents. Before conducting the survey, the benefits identified from SLR and interviews were mapped together, and included in the survey questionnaire. Also, an open ended question was added in the survey to identify any additional benefits of implementing DevOps in organizations.\n\nBased on the responses obtained from the survey, a finalized list of the benefits of implementing DevOps in organizations is created. The mostly stated responses are added first, followed by the lesser stated responses and so on. The final list of benefits of implementing DevOps in organizations where agile development is in practice is presented in the following table\nChapter 6. Discussion\n\nBenefits of implementing DevOps in organizations where agile is in practice\n\n<table>\n<thead>\n<tr>\n<th>Benefits</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Increased collaboration between Dev and Ops teams</td>\n</tr>\n<tr>\n<td>Frequent software releases</td>\n</tr>\n<tr>\n<td>Improved quality of software deployments</td>\n</tr>\n<tr>\n<td>Reduced time to market</td>\n</tr>\n<tr>\n<td>Faster feedback</td>\n</tr>\n<tr>\n<td>Reduced release cycle time</td>\n</tr>\n<tr>\n<td>Easier detection of failures</td>\n</tr>\n<tr>\n<td>Smooth and faster workflow</td>\n</tr>\n<tr>\n<td>Increased customer satisfaction</td>\n</tr>\n<tr>\n<td>Rapid product delivery</td>\n</tr>\n<tr>\n<td>Improved code quality</td>\n</tr>\n<tr>\n<td>Increased overall organizational efficiency</td>\n</tr>\n<tr>\n<td>Easier tracking</td>\n</tr>\n<tr>\n<td>Increased system stability</td>\n</tr>\n<tr>\n<td>Breaks down silos</td>\n</tr>\n<tr>\n<td>Increased software reliability</td>\n</tr>\n<tr>\n<td>Increased responsiveness to business needs</td>\n</tr>\n<tr>\n<td>Empathy between Dev and Ops teams</td>\n</tr>\n<tr>\n<td>Reduced need for rework</td>\n</tr>\n<tr>\n<td>Balance between cost and quality</td>\n</tr>\n<tr>\n<td>Minimal manual intervention</td>\n</tr>\n<tr>\n<td>Reduced communication overhead</td>\n</tr>\n<tr>\n<td>Automation</td>\n</tr>\n<tr>\n<td>Increased predictability of releases</td>\n</tr>\n<tr>\n<td>Easier implementation of customer requirements</td>\n</tr>\n<tr>\n<td>Increased revenue</td>\n</tr>\n</tbody>\n</table>\n\nAdditional benefits identified through survey\n\n<table>\n<thead>\n<tr>\n<th>Benefits</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Less stressful and faster deployments</td>\n</tr>\n<tr>\n<td>Employee satisfaction</td>\n</tr>\n<tr>\n<td>Lesser roll backs</td>\n</tr>\n<tr>\n<td>Better performance of both people and systems</td>\n</tr>\n<tr>\n<td>Budget control</td>\n</tr>\n<tr>\n<td>Faster resolution of problems</td>\n</tr>\n<tr>\n<td>More stable operating environments</td>\n</tr>\n<tr>\n<td>Advantage over rival companies that do not do DevOps</td>\n</tr>\n<tr>\n<td>Minimized deployment related downtime</td>\n</tr>\n</tbody>\n</table>\n\nTable 6.1: Final List of Benefits\n\nRQ2: What are the challenges faced by the organizations while adopting DevOps?\nChapter 6. Discussion\n\nIdentifying the challenges to the DevOps adoption process is another aim of this research. The challenges faced while adopting DevOps in organizations in general were identified from the literature, also several new challenges were identified from the interviews and survey. Before conducting the survey, the challenges identified from SLR and interviews were mapped together, and included in the survey questionnaire. Also, an open ended question was added in the survey to identify any additional challenges faced during DevOps adoption in organizations.\n\nBased on the responses obtained from the survey, a finalized list of the challenges of implementing DevOps in organizations is created. The most important challenges identified from the survey responses are listed first, followed by the lesser important challenges and so on. The final list of challenges faced by organizations while adopting DevOps is presented in the following table.\n\n<table>\n<thead>\n<tr>\n<th>Challenges faced during DevOps adoption</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Culture and mindset of long timers</td>\n</tr>\n<tr>\n<td>Legacy software</td>\n</tr>\n<tr>\n<td>Technical debt</td>\n</tr>\n<tr>\n<td>Integrating new tools with existing company tools</td>\n</tr>\n<tr>\n<td>Lack of proper management structure</td>\n</tr>\n<tr>\n<td>Learning curve</td>\n</tr>\n<tr>\n<td>Designing software architectures to make them work with DevOps</td>\n</tr>\n<tr>\n<td>No proper training for DevOps</td>\n</tr>\n<tr>\n<td>Resistance from employees</td>\n</tr>\n<tr>\n<td>Complexity due to multiple production environments</td>\n</tr>\n<tr>\n<td>Lack of proper resources to configure environments</td>\n</tr>\n<tr>\n<td>Security clearances when handling sensitive data</td>\n</tr>\n<tr>\n<td>Fear of change</td>\n</tr>\n<tr>\n<td>Monolithic system architecture</td>\n</tr>\n<tr>\n<td>Limited visibility of production environments</td>\n</tr>\n<tr>\n<td>Buy-in from senior management</td>\n</tr>\n<tr>\n<td>Organizational structure</td>\n</tr>\n<tr>\n<td>Hidden complexities and hidden costs</td>\n</tr>\n<tr>\n<td>Making everyone accustomed to a new workflow</td>\n</tr>\n<tr>\n<td>Insufficient knowledge on applications and environments in case of outsourced projects</td>\n</tr>\n<tr>\n<td>Buy-in from customer</td>\n</tr>\n<tr>\n<td>Lack of proper automation tools in embedded systems domain</td>\n</tr>\n<tr>\n<td>Fear of measurement in employees</td>\n</tr>\n<tr>\n<td>Geographical distribution of Dev and Ops teams</td>\n</tr>\n<tr>\n<td>Buzzword perception</td>\n</tr>\n<tr>\n<td>Writing custom scripts for automating tasks</td>\n</tr>\n</tbody>\n</table>\nChapter 6. Discussion\n\nFear of failure in managers\nUnclear definition and goals of DevOps adoption\n**Additional challenges identified from survey**\nUnawareness of right tools for doing tasks\nInsufficient knowledge on modifying current architecture to suit an automated environment\nFinding the right and experienced personnel\n\n<table>\n<thead>\n<tr>\n<th><strong>Table 6.2: Final List of Challenges</strong></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>It is better to start DevOps in small projects</td>\n</tr>\n<tr>\n<td>Conduct short meetings to encourage communication between teams</td>\n</tr>\n<tr>\n<td>Proper training of employees</td>\n</tr>\n<tr>\n<td>Clarify issues that arise as soon as possible</td>\n</tr>\n<tr>\n<td>Hire people with a DevOps mindset</td>\n</tr>\n<tr>\n<td>Use a flexible architecture</td>\n</tr>\n<tr>\n<td>Provide a better understanding of business requirements to every employee</td>\n</tr>\n<tr>\n<td>Having a proper management structure</td>\n</tr>\n<tr>\n<td>Have a Proof of Concept in place</td>\n</tr>\n<tr>\n<td>Minimize hand-offs using an open communication channel and a good alignment of teams</td>\n</tr>\n<tr>\n<td>Specify release criteria for each project and document challenges that pop up</td>\n</tr>\n</tbody>\n</table>\n\n**RQ3:** How to overcome the challenges faced by the organizations in adopting DevOps?\n\nAnother aim of this research is to identify the solutions/ mitigation strategies to overcome the challenges faced during DevOps adoption. Identifying the solutions to overcome the challenges inherent with DevOps adoption can guide organizations whenever faced with a challenge. Also, several problems can be avoided in the first place if the organizations have an idea about the DevOps adoption challenges and their mitigation strategies. There is no literature related to the solutions to overcome the DevOps adoption challenges, but the solutions were identified from the interviews and survey. The solutions identified from the interviews were added to the survey questionnaire. Also, an open ended question was added in the survey to identify any additional solutions to overcome the DevOps adoption challenges.\n\nBased on the responses obtained from the survey, a finalized list of the solutions to overcome the DevOps adoption challenges is created. The mostly stated solutions identified from the survey responses are listed first, followed by the lesser stated solutions and so on. The final list of solutions to overcome the DevOps adoption challenges is presented in the following table.\nDocument errors and their solutions\n\n| Estimate DevOps adoption costs and risks before adopting DevOps |\n| Include Quality Assurance people |\n| Make decisions prior to start of projects |\n| Use tools (e.g. CloudShell) to bridge the compatibility gap between legacy and cloud based tools |\n\n**Additional solutions identified from survey**\n- Encourage bonding of people and breaking down of silos\n- Communication is basic\n- Training and hiring those who possess a greater degree of empathy\n\nTable 6.3: Final List of Solutions\n\n**RQ4:** What are the practices that an organization needs to include while adopting DevOps?\n\nIdentifying the practices that organizations must include as part of the DevOps adoption process is another aim of this research. The different practices of DevOps were identified from the literature, and also from the interviews and survey. Before conducting the survey, the practices identified from SLR and interviews were mapped together, and included in the survey questionnaire. Also, an open ended question was added in the survey to identify any other practices of DevOps.\n\nBased on the responses obtained from the survey, a finalized list of the practices of DevOps is created. The mostly stated practices from the survey responses are listed first, followed by the lesser stated practices and so on. The final list of DevOps practices is presented in the following table.\n\nTo support the above mentioned technical practices, it has been noted that organizations should adopt the principles of Culture, Automation, Collaboration, Measurement, and Sharing. Also, it has been noted that is no specific way of doing DevOps, and organizations will adopt the different tools and practices based on the organizational structure, capabilities, project needs, requirements, and project type.\n\n<table>\n<thead>\n<tr>\n<th>DevOps Practices</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Continuous Integration</td>\n</tr>\n<tr>\n<td>Continuous Testing</td>\n</tr>\n<tr>\n<td>Continuous Delivery</td>\n</tr>\n<tr>\n<td>Continuous Deployment</td>\n</tr>\n<tr>\n<td>Continuous Monitoring</td>\n</tr>\n<tr>\n<td>Continuous Feedback</td>\n</tr>\n<tr>\n<td>Continuous Planning</td>\n</tr>\n</tbody>\n</table>\n\nTable 6.4: Final List of Practices\n\n**RQ5:** What are the problems faced by the DevOps teams during continuous integration, deployment and testing?\n\nThe DevOps teams need to work together to continuously integrate, deploy and test the code, during which the teams may face some problems. Identifying the problems faced by the DevOps teams during the continuous activities of integration, deployment and testing is another aim of this research. There is no literature related to the problems faced by DevOps teams during continuous integration, deployment and testing, but the problems were identified from the interviews and survey. The problems identified from the interviews were added to the survey questionnaire. Also, an open ended question was added in the survey to identify any additional problems faced by the DevOps teams.\n\nBased on the responses obtained from the survey, a finalized list of the problems faced by the DevOps teams is created. The mostly stated problems identified from the survey responses are listed first, followed by the lesser stated problems and so on. The final list of problems faced by DevOps teams is presented in the following table.\n\n<table>\n<thead>\n<tr>\n<th>Problems faced by DevOps teams during CI, CD and CT</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Configuring infrastructure for the first time</td>\n</tr>\n<tr>\n<td>Tool related issues</td>\n</tr>\n<tr>\n<td>Production failures</td>\n</tr>\n<tr>\n<td>Learning new technologies</td>\n</tr>\n<tr>\n<td>Lack of proper communication between teams</td>\n</tr>\n<tr>\n<td>Testing environment flakiness</td>\n</tr>\n<tr>\n<td>Connectivity issues during integration</td>\n</tr>\n<tr>\n<td>Reverting from database changes</td>\n</tr>\n<tr>\n<td>Getting resources for solving workflow problems</td>\n</tr>\n<tr>\n<td>Lack of collocated teams</td>\n</tr>\n<tr>\n<td>Overlapping of different project time plans</td>\n</tr>\n<tr>\n<td>Accessibility</td>\n</tr>\n<tr>\n<td>Having to manually check for application logs in Jenkins</td>\n</tr>\n</tbody>\n</table>\n\n**Additional problems identified from survey**\n\n- Entrenched differences/antagonism between teams\n- Picking up the right tools\n- Changing and complex software architectures\n- Undocumented legacy systems with no enough knowledge\n- Lack of ownership by various teams\n- Getting support for open source tools\n\nTable 6.5: Final List of Problems\nChapter 7\n\nConclusions and Future Work\n\nDevOps is a new phenomenon that gained huge popularity in the past few years. Several major companies like Facebook, Netflix and Yahoo are implementing DevOps [29] [3]. However, there is very little literature available on DevOps, and the studies are often of low quality. This research is thus focused on contributing towards a better understanding of how DevOps works in an organization.\n\nThe study has focused on identifying the benefits of implementing DevOps in organizations where agile development is in practice, challenges that are faced by organizations during DevOps adoption, the solutions/strategies to overcome these challenges, the different DevOps practices, and the problems faced by DevOps teams during continuous integration, deployment and testing.\n\nA mixed methods approach has been employed to conduct the research. An exploratory sequential mixed methods design is followed, where qualitative research will be conducted first, followed by quantitative research. Systematic Literature Review (SLR) and interviews were conducted first, followed by an online survey to validate the qualitative results. Using SLR, answers were found for RQ1, RQ2 and RQ4. It was noted that, the perceived benefits of implementing DevOps in software organizations in general were listed in most of the literature. Only the studies [45] [47] [5] [33] reported on the benefits achieved in practice by DevOps adoption in organizations. The DevOps adoption challenges were elucidated in the studies [42] [22] [28]. Smeds et al. [42] identified the challenges to DevOps adoption in the cloud services domain. But their study was limited to only one organization, which was in the initial stages of DevOps adoption. Jones et al. [22] conducted a case study and identified the DevOps adoption challenges in the embedded systems domain. Smeds et al. [42] mentioned the need to conduct further research by including more organizations for generalizing the DevOps adoption challenges in organizations.\n\nAlso, it was observed that no studies addressed the solutions to overcome the DevOps adoption challenges. There is no clear understanding of the DevOps practices in literature. No studies have reported on the problems faced by DevOps teams during continuous integration, deployment and testing. To identify the benefits of adopting DevOps\nin organizations where agile development is in practice, interviews were conducted. 12 different practitioners from 11 different software organizations were interviewed, and the DevOps adoption benefits were identified after thematically coding the interview data. Also, several new challenges to DevOps adoption, and solutions to overcome the challenges were identified from the interviews. A clear understanding of the DevOps practices was gained after analysing the interview data. Further, many problems faced by DevOps teams during continuous integration, deployment and testing were identified from the interviews. Thus, all the research questions were answered using the interview data.\n\nThe purpose of exploratory sequential design is to validate if the data from a small population sample can be generalized to a larger population sample. Hence, the results from both SLR and interviews were mapped together, and included in the online survey questionnaire. 50 complete responses were considered for statistical analysis. Descriptive statistics was used to analyse the survey responses. Using the survey, the qualitative results are validated, and some new results were also identified. The survey results helped in identifying the benefits of adopting DevOps in organizations, challenges faced by organizations while adopting DevOps, solutions to overcome the challenges, the different practices of DevOps, and the problems faced by DevOps teams during continuous integration, deployment, and testing. Increased collaboration between Dev and Ops teams, frequent software releases, improved quality of software deployments, reduced time to market, and faster feedback were identified as benefits by most of the respondents. Also, the respondents were asked to specify the level of difficulty of each challenge. It was identified that culture and mindset of long timers, legacy software, technical debt, tool integration, lack of proper management structure, and learning curve are the most challenging factors for DevOps adoption. The mostly stated solutions were identified as starting DevOps in small projects, conducting meetings to encourage communication between teams, proper training of employees, clarifying issues immediately, and hiring people with a DevOps mindset. The DevOps practices were identified as continuous integration, testing, delivery, deployment, monitoring and feedback. The problems faced by DevOps teams were identified as configuring infrastructure for the first time, tool related issues, production failures, learning new technologies, and lack of proper communication between teams.\n\nThe results were categorized into final lists for each research question, and the mostly stated answers were listed first, followed by the lesser stated ones. Also, some additional benefits, challenges, solutions, practices and problems were specified by the respondents in the open-ended questions included in the survey. Only the most frequently specified answers were included in the final lists. Thus, the challenges identified by Smeds et al. [42] were validated by including more organizations in the interviews and survey. Also, several additional benefits and challenges of DevOps adoption were identified. The final data is valid, as the SLR and interview findings were validated using the survey.\nChapter 7. Conclusions and Future Work\n\nIt was learnt that companies should not adopt DevOps just because it is a fancy buzzword, and they need to keep in mind the risks and challenges inherent with DevOps adoption. Based on the organizational structure, capabilities, project type, requirements and needs, the adoption of DevOps tools and practices varies. This finding is in-line with the study [47]. Thus, the study provides researchers and software practitioners a clear idea on the benefits of implementing DevOps in organizations where agile is in practice, the challenges that may occur during DevOps adoption, some solutions to overcome the challenges, the practices of DevOps and the problems faced by DevOps teams during continuous integration, deployment and testing.\n\n7.1 Future Work\n\nIt has been observed that there are very few high quality studies related to DevOps, as it is a relatively new concept. There is a lot of scope for empirical work in this domain. In our study, the benefits of adopting DevOps, challenges, solutions, practices and problems were studied in general DevOps adoption scenarios. As the adoption of DevOps tools and practices in organizations is dependent on factors like organizational structure, capabilities, project needs, requirements, and project types, some of the identified results could be contextual. For example, the challenges faced in a small organization adopting DevOps might vary from the challenges faced in a large organization. A case study can be performed to validate the results. The cause effect factors that may impact the results identified can be investigated by conducting an empirical study. For example, the impact of culture on DevOps adoption can be investigated. Also, no studies address the solutions to overcome DevOps adoption challenges, and problems faced by DevOps teams during continuous integration, deployment and testing. We have covered this gap, but more research could be performed in this aspect. Further, it is learnt that for transitioning to DevOps, a lot of changes must be made in an organization. It would be interesting to investigate what changes must be made in an organization for transitioning into a full DevOps state. There is currently no proper research on the tools needed for supporting DevOps. The availability of DevOps tools, and their functioning can be studied.\nReferences\n\n\nReferences\n\n\nAppendix A- Primary Studies for SLR\n\nS2 : 2015, \"A DevOps Approach to Integration of Software Components in an EU Research Project\" [45]\nS5 : 2015, \"Dimensions of DevOps\" [29]\nS7 : 2014, \"Strengthening harmonization of Development (Dev) and Operations (Ops) silos in IT environment through Systems approach\" [21]\nS8 : 2015, \"Toward Unified DevOps Model\" [48]\nS9 : 2015, \"Understanding DevOps and Bridging the gap from Continuous Integration to Continuous Delivery\" [47]\nS11 : 2011, \"DevOps: So You Say You Want a Revolution?\" [18]\nS14 : 2016, \"DevOps Making It Easy to Do the Right Thing\" [5]\nS15 : 2012, \"Don't Install Software By Hand\" [43]\nS17 : 2016, \"CMMI Guided Process Improvement for DevOps Projects: An Exploratory Case Study\" [39]\nS18 : 2015, \"On the journey to continuous deployment: Technical and Social challenges along the way\" [6]\nS19 : 2016, \"Being a DevOps Developer\" [44]\nS20 : 2016, \"On the Impact of Mixing Responsibilities Between Dev and Ops\" [33]\nS21 : 2015, \"DevOps: A Definition and Perceived Adoption Impediments\" [42]\nS24 : 2016, \"Management Challenges for DevOps Adoption within UK SMEs\" [22]\nS30 : 2011, \"Why Enterprises Must Adopt DevOps to Enable Continuous Delivery\" [20]\nAppendix B- Interview Questionnaire\n\n1. Can you tell us about your experience in working with DevOps?\n\n2. Can you describe about the methodology your organization followed before adopting DevOps?\n\n3. So, why did your organization decide to adopt DevOps?\n\n4. From what we have learned from literature, there is no specific DevOps process. Rather, it is viewed as a framework and organizations must include the DevOps principles and practices in their processes. What can you say about this?\n\n5. Can you tell us about the principles and practices of DevOps?\n\n6. Let us say, an organization wants to adopt DevOps. What principles and practices do you think it must include in its development process for this purpose?\n\n7. Can you tell us about which practices of DevOps your organization has included?\n\n8. Can you tell us about the benefits of adopting DevOps in organizations?\n\n9. What benefits did your organization achieve after adopting DevOps?\n\n10. Do you think the DevOps adoption process can be challenging for organizations which are implementing it for the first time?\n\n11. Can you describe about the possible challenges that an organization may face during the starting stages of the adoption process?\n\n12. Now, let us say the organization has moved past the initial stages of adoption. What are the possible challenges that await? Can you describe about them in detail?\n\n13. What do you think are the solutions to overcome these challenges? Can you describe about them in detail?\n\n14. Can you tell us about the challenges that your organization came across while adopting DevOps in your experience, if any?\n15. Can you describe about what strategies your organization used to overcome the challenges?\n\n16. Also, the DevOps teams must work together for continuous integration, deployment and testing. Can you tell us about the problems the DevOps teams face during continuous integration, deployment and testing?\n\n17. Can you give a few examples from your experience, about the problems that the DevOps teams usually face?\n\n18. Do you have anything more to add?\nAppendix C- Survey Questionnaire\n\nDear Software Engineering Practitioners,\n\nWe are Master’s students at Blekinge Institute of Technology, Sweden. As part of our Master’s Thesis, we are conducting a survey to learn about the adoption of DevOps in software organizations.\n\nThis survey won’t take more than 15 minutes and can be completed by any software practitioner who has worked with DevOps. There is currently very little research related to DevOps. By answering this survey questionnaire, you can help in contributing to the research pool and in improving the perception of software organizations regarding DevOps.\n\nYour response would be invaluable to our research, and contribute greatly to the DevOps research community. All your responses are strictly confidential, and will only be accessed by the two researchers. Your anonymity will be preserved, and no details about an individual person or organization will be included in the thesis. We would be really grateful if you can forward this questionnaire to your contacts who are also DevOps practitioners, and encourage them to answer.\n\nThank you in advance.\n\nBest Regards,\nAnand and Swetha\nAdoption of DevOps in Software Organizations\n\nThis survey questionnaire is designed to identify the benefits of adopting DevOps in organizations, challenges faced during adoption, strategies to overcome these challenges, the DevOps practices, and the problems faced by DevOps teams during continuous integration, deployment and testing. Please participate by adding as much detail as you can.\n\n*Required\n\n1. The type of organization in which you work *\n Select all that apply\n Tick all that apply.\n - Consumer-oriented software\n - Business oriented software\n - Design and Engineering software\n - Information display and transaction entry\n - Operating Systems\n - Networking/Communications\n - Device/Peripheral drivers\n - Support utilities\n - Middleware and system components\n - Software Backplanes (e.g. Eclipse)\n - Servers\n - Malware\n - Hardware Control\n - Embedded Software\n - Real time control software\n - Process control software (i.e. air traffic control, industrial process, nuclear plants)\n - Operations research\n - Information management and manipulation\n - Artistic creativity\n - Scientific software\n - Artificial Intelligence\n - Other: ..................................................................................................................\n\n2. Geographical location of your organization *\n\n........................................................................................................................................\n\nhttps://docs.google.com/forms/d/1Qy_u6OPvrzEZzaBTWS4i30ij4J0zw_QElNXIQDA1Zk/edit\n3. Size of your organization *\n *Mark only one oval.\n - < 10\n - 10-50\n - 50-500\n - 500-5000\n - > 5000\n\n4. Your role in the organization *\n\n5. Work Experience *\n Enter number of years\n\n6. Experience with DevOps *\n Enter number of years\n\n7. Development Methodology in your organization before adopting DevOps *\n *Mark only one oval.\n - Plan-driven Methodologies\n - Agile Methodologies\n - Hybrid Methodology\n - Other:\n8. **Identify which of these benefits can be achieved after implementing DevOps in organizations**\n\n Select all that apply\n\n - Increased collaboration between Dev and Ops team members\n - Empathy between Dev and Ops teams\n - Improved quality of software deployment\n - Increased software reliability\n - Frequent software releases\n - Improved code quality\n - Faster feedback\n - Reduced communication overhead\n - Reduced time to market\n - Reduced release cycle time\n - Reduced need for re-work\n - Smooth and faster work flow\n - Automation\n - Increased system stability\n - Easier implementation of customer requirements\n - Increased predictability of releases\n - Rapid delivery of products\n - Increased customer satisfaction\n - Minimal manual intervention\n - Balance between cost and quality\n - Increased responsiveness to business needs\n - Increased revenue\n - Increased overall organizational efficiency\n - Breaks down silos\n - Easier tracking\n - Easier detection of failures\n\n9. **Please specify any other benefits of implementing DevOps, which are not listed in the previous question, which you feel are achieved with DevOps**\n\n \n\n10. **Do you think the DevOps adoption process can be challenging for organizations implementing it for the first time?**\n\n *Mark only one oval per row.*\n11. Which of the following can be more challenging for an organization while adopting DevOps? * \nSelect one in each row \nMark only one oval per row.\n\n<table>\n<thead>\n<tr>\n<th></th>\n<th>Very challenging</th>\n<th>Challenging</th>\n<th>Somewhat challenging</th>\n<th>Not challenging</th>\n<th>Can't specify</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1. Lack of proper management structure</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>2. No proper training</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>3. Geographical distribution of Dev and Ops teams</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>4. Integrating new tools with existing company tools</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>5. Legacy software</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>6. Resistance from employees</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>7. Monolithic system architecture</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>8. Organizational structure</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>9. Hidden complexities and hidden costs</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>10. Complexity due to multiple production environments</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>11. Designing software architectures to make them work with DevOps</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>12. Technical debt</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>13. Buzzword perception</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>14. Unclear definition and goals of DevOps adoption</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>15. Security clearances (when handling sensitive data)</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>16. Buy-in from senior management</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>17. Buy-in from customer</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>18. Fear of change</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>19. Fear of failure in managers</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>20. Insufficient knowledge on applications and environments (in outsourcing projects)</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>21. Making everyone accustomed to a new workflow</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>22. Writing custom scripts for automating tasks</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>23. Learning curve</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>24. Lack of proper resources to configure environments</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>25. Fear of measurement in employees</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>26. Culture and mindset of longtimers</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>27. Limited visibility of</td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n28. Lack of proper automation tools in embedded systems domain\n\n12. Specify any other challenges which are not listed in the previous question, that you think are faced while adopting DevOps *\n\n13. Which of the following mitigation strategies can be used to address the DevOps adoption challenges? *\nSelect all that apply\nTick all that apply.\n\n- Better to start DevOps in small projects\n- Estimate adoption costs and risks before adopting DevOps\n- Properly training the employees\n- Conducting short meetings to encourage communication between teams\n- Clarifying issues that arise, as soon as possible\n- Providing a better understanding of business requirements to every employee\n- Use tools like CloudShell and Helion CloudSystem to bridge compatibility gap between legacy tools and new cloud based tools\n- Minimize hand-offs using an open communication channel and good alignment of teams\n- Using a flexible architecture\n- Specify release criteria for every project and document the challenges that pop-up\n- Have a Proof of Concept POC in place\n- Include Quality Assurance people\n- Hire people with a DevOps mindset\n- Document errors and their solutions\n- Make decisions prior to the start of projects\n- Have a proper management structure\n\n14. Suggest any other mitigation strategies (that are not listed in the previous question) which you think can solve the DevOps adoption challenges *\n\n...\n15. What is your opinion on the description of DevOps as not a specific process, but rather a framework of principles and practices that organizations must include into their development processes? *\n\nMark only one oval per row.\n\n<table>\n<thead>\n<tr>\n<th>Strongly Disagree</th>\n<th>Disagree</th>\n<th>Neither agree nor disagree</th>\n<th>Agree</th>\n<th>Strongly Agree</th>\n</tr>\n</thead>\n</table>\n\n16. Which of the following practices of DevOps should an organization include in its development process? *\n\nSelect all that apply\n\n- Continuous Planning\n- Continuous Integration\n- Continuous Deployment\n- Continuous Delivery\n- Continuous Testing\n- Continuous Monitoring\n- Continuous Feedback\n\n17. Please mention any other practices of DevOps that are not listed in the previous question *\n\n..............................................................................................................................................................................\n..............................................................................................................................................................................\n..............................................................................................................................................................................\n..............................................................................................................................................................................\n..............................................................................................................................................................................\n\n18. Which of these problems might DevOps teams face during Continuous Integration, Deployment and Testing? *\n\nSelect all that apply\n\n- Lack of proper communication between employees may cause delay in deployments\n- Tool problems (For e.g. Legacy tools won’t be compatible with modern tools, finding the right tools)\n- Time plans of the projects may overlap due to the lags in other projects\n- Configuring infrastructure for the first time\n- Learning new technologies\n- Connectivity issues during integration\n- Getting resources for solving the work flow problems\n- Testing environment flakiness\n- Reverting from database changes\n- Production failures\n- Accessibility\n- Having to manually check for application logs in Jenkins\n- Teams might not be collocated\n19. Mention any other problems faced by DevOps teams (that are not listed in the previous question) which you feel are important *\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n20. Can you specify the benefits achieved in your organization after implementing DevOps? *\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n21. Can you state any challenges faced during DevOps adoption in your organization? *\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n22. Please specify the DevOps practices that you have included in your organization *\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n23. Can you specify the problems DevOps teams in your organization face during Continuous Integration, Deployment and Testing? *\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n\n----------------------------------------------------------------------------------------------------------------------------------\n24. Do you have anything more to add?\n\n--------------------------------------------------------------------------------------------------\n\n--------------------------------------------------------------------------------------------------\n\n--------------------------------------------------------------------------------------------------\n\n--------------------------------------------------------------------------------------------------\n\n25. Include your name and email\n\nYour details are completely confidential\n\n--------------------------------------------------------------------------------------------------"}}},{"rowIdx":91,"cells":{"id":{"kind":"string","value":"37c94f4c43c95d9806a358c0be1a0a3cdb89424b"},"text":{"kind":"string","value":"Automation of retrieval, transformation and uploading of genomic data and their metadata for their integration into a GDM repository\n\nJORGE IGNACIO VERA PENA\n\nMEMORIA DE TITULACIÓN PARA OPTAR AL TÍTULO DE\n\nINGENIERO CIVIL INFORMÁTICO\n\nPROFESOR GUÍA: ANDRÉS MOREIRA\n\nPROFESOR CORREFERENTE: MARCO MASSEROLI\n\nOCTUBRE 2018\nAutomation of retrieval, transformation and uploading of genomic data and their metadata for their integration into a GDM repository\n\nJORGE IGNACIO VERA PENA\n\nMEMORIA DE TITULACIÓN PARA OPTAR AL TÍTULO DE\n\nINGENIERO CIVIL INFORMÁTICO\n\nPROFESOR GUÍA: ANDRÉS MOREIRA\n\nPROFESOR CORREFERENTE: MARCO MASSEROLI\n\nOCTUBRE 2018\nAcknowledgements\n\nThanks to all the GeCo team, in particular to Professor Masseroli for welcoming me into this challenging project with great and constructive critical view along the development of GMQLImposter.\n\nSpecial thanks to Arif for guiding and helping me with the development of this work, your unconditional support, in the personal and in the technical; you helped me a lot. Sincerely it was a pleasure working with you and I hope to do so again in the future.\n\nGracias a toda mi familia por todo el apoyo y la oportunidad de embarcarme en esta aventura en Italia, esta experiencia concluye con la entrega de mi tesis; pero no solamente es eso, casi 3 años en los que pude descubrir más del mundo y pude también convertirme en una persona mucho más completa, con un mejor punto de vista ante los problemas que se vienen en adelante. Gracias por estar conmigo en todas y a pesar de haberme ido solo, nunca me sentí así.\n\nThanks to everyone I met and lived with in Italy and have become good Friends, living abroad has been an incredible experience and it is because of you.\n\nMuchas gracias a todos!\n\nNacho 2017\n# Table of Contents\n\nAbstract .................................................................................................................. 1\nAbstract in Spanish ................................................................................................. 2\nChapter 1. Introduction ......................................................................................... 3\nChapter 2. Background Information .................................................................... 5\n 2.1 Next generation sequencing (NGS) ............................................................. 5\n 2.2 Genomic Data Model (GDM) ..................................................................... 6\n 2.3 Data sources ................................................................................................. 7\n 2.3.1 TCGA ................................................................................................. 7\n 2.3.2 TCGA2BED ....................................................................................... 8\n 2.3.3 ENCODE project ............................................................................. 8\nChapter 3. State of the art .................................................................................. 9\n 3.1 GenoMetric Query Language (GMQL) ..................................................... 9\n 3.2 Genome Query Language (GQL) ............................................................. 10\n 3.3 Other solutions .......................................................................................... 10\n 3.4 Summary .................................................................................................... 10\nChapter 4. Thesis Goal ....................................................................................... 11\nChapter 5. Software design ............................................................................... 12\n 5.1 Architecture design ................................................................................... 12\n 5.1.1 Requirement analysis ........................................................................ 12\n 5.1.2 Source and dataset analysis .............................................................. 14\n 5.1.3 General description for the 3 steps design ....................................... 14\n 5.2 XML design ............................................................................................... 16\n5.3 Database design.......................................................... 21\n 5.3.1 Sources, datasets and files ........................................ 22\n 5.3.2 Statistics .......................................................... 22\n 5.3.3 Configuration...................................................... 22\n 5.3.4 Database model .................................................. 23\nChapter 6. Implementation .................................................................. 26\n 6.1 Downloader .................................................................... 26\n 6.2 Transformation .................................................................. 27\n 6.3 Loader ........................................................................... 27\n 6.4 Fault tolerance ................................................................... 28\n 6.5 Logging ........................................................................... 28\n 6.6 Technologies used .......................................................... 29\n 6.6.1 Scala ....................................................................... 29\n 6.6.2 SLF4J + log4j .......................................................... 30\n 6.6.3 Maven ....................................................................... 30\n 6.6.4 H2Database ............................................................ 31\nChapter 7. Evaluation ......................................................................... 32\n 7.1 Configuration XML creation .............................................. 32\n 7.2 Changes of implementation and adaptation ......................... 33\n 7.3 Parallel run ....................................................................... 33\n 7.4 Results ............................................................................. 33\nChapter 8. Conclusion and future work ............................................... 37\nReferences ....................................................................................... 38\nAppendix A. Requirements Analysis for GMQLImporter .................... 40\nAppendix B. Specifications for GMQLImporter ................................................................. 49\nAppendix C. ENCODE Metadata Explanation for GDM.......................................................... 59\nAppendix D. XSD schema for GMQLImporter configuration file .............................................. 63\nAppendix E. Database design for GMQLImporter ................................................................... 69\nAppendix F. GMQLImporter console & file logging ............................................................... 74\nAppendix G. Creation of XML configuration file for GMQLImporter ....................................... 80\nAppendix H. TCGA2BED datasets organization ..................................................................... 106\nAppendix I. ENCODE metadata generation for experiment JSON .......................................... 109\nAppendix J. Console manual for GMQLImporter ................................................................. 135\nAppendix K. Metadata replacement for ENCODE in GMQLImporter .................................... 136\n\nList of figures\n\nFigure 2:1 Cost per genome over the years by NIH research institute .......................... 5\nFigure 5:1 initial domain model for GMQLImporter .......................................................... 13\nFigure 5:2 root node of the GMQLImporter configuration XSD schema ......................... 17\nFigure 5:3 source node of the GMQLImporter configuration XSD schema ...................... 18\nFigure 5:4 dataset node of the GMQLImporter configuration XSD schema ................. 20\nFigure 5:5 dataset node of the GMQLImporter configuration XSD schema ............... 21\nFigure 5:6 database model for GMQLImporter ............................................................... 23\nFigure 5:7 file status usage diagram for GMQLImporter ................................................. 25\n\nList of tables\n\nTable 5:1 proposed initial entities for GMQLImporter development ............................. 13\nTable 7:1 datasets from ENCODE and TCGA2BED to be imported................................. 33\nTable 7:2 execution times in with and without parallelization for dataset ................. 35\nAbstract\n\nDue to NGS techniques, whole genome sequences are produced much cheaper and faster every year, thus genomic data is being gathered at a pace never seen before. By processing NGS data new sense making relationships between genomic regions are being found and fundamental biological questions are answered; therefore managing NGS data now seems to be the most important big data problem of humankind.\n\nAs the new NGS data generated are mostly heterogeneous, they are not easily interoperable. The Genomic Data Model (GDM) allows describing NGS data in a homogeneous way for their interoperation. GMQL is a next-generation query language that by means of using GDM data, gives genomics specific domain operations to biologists to process large volumes of data for discovering biological knowledge.\n\nThis thesis studies the improvement of NGS data analysis by automating and standardizing the genomic data and their experimental metadata integration into a GDM repository. The software developed is GMQLImporter; it extracts NGS data from multiple data providers, transforms the data according to GDM specifications and loads standardized GDM datasets into GMQL for further querying.\n\nGMQLImporter was tested to download, transform and load into a GDM repository 133,648 samples gathered from 2 different data providers and organized into 16 datasets. This work provides the capabilities to be easily extended to include samples from new data sources and in this way provide more NGS data to be queried and making new discoveries in bioinformatics.\nAbstract in Spanish\n\nA causa de las tecnologías NGS, las secuencias completas del genoma se producen cada vez más rápido y barato cada año, esto implica que la obtención de datos genómicos tiene un ritmo nunca antes visto. Procesando estos datos NGS se están descubriendo nuevas relaciones entre distintas regiones genómicas y se están encontrando respuestas a preguntas biológicas fundamentales. Por lo tanto parece que manejar los datos NGS ahora es el problema de big data más importante de la humanidad.\n\nDado que los nuevos datos NGS son mayormente heterogéneos, no son fácilmente interoperables. El Genomic Data Model (GDM) permite describir datos NGS y sus metadatos de manera homogénea para su interoperabilidad. GMQL es un next-generation query language que usando el modelo GDM, entrega a biólogos herramientas específicas del dominio genómico para procesar gran volumen de datos para así poder generar nuevo conocimiento biológico.\n\nEste trabajo estudia la mejora del análisis de datos NGS mediante la estandarización y automatización de la integración de los datos experimentales y sus metadatos en un repositorio GDM. El software desarrollado es GMQLImporter, que extrae datos NGS de múltiples proveedores, los transforma de acuerdo a las especificaciones del GDM y carga los conjuntos de datos estandarizados en el sistema GMQL para posterior consulta.\n\nGMQLImporter fue testeado para descargar, transformar y cargar en el repositorio de GMQL 133.648 muestras obtenidas de 2 proveedores de datos distintos y distribuidos en 16 conjuntos de datos. GMQLImporter permite ser extendido fácilmente para así incorporar muestras de nuevas fuentes de datos y de este modo disponer mayor cantidad de datos NGS para interrogar y generar nuevos conocimientos en la bioinformática.\nChapter 1. Introduction\n\nThe rise of NGS technologies, thanks to their high throughput, is producing more genomic data than ever before, entire genomes can be sequenced within one day and several consortia are publishing this experimental data to be publicly available. By querying NGS data, fundamental biological questions are now being found; therefore, managing NGS data now seems to be the most important big data problem for humankind.\n\nThe bioinformatics have been mostly challenged by the primary analysis, the production of sequences from the DNA segments or reads and the secondary analysis, alignment of reads to a reference genome and search for specific features, such as variants/mutations and peaks of expression. The most important problem that has been occurring is called tertiary analysis, which is used to find sense making relationships to explain how different regions in the genome interact with each other. This newly generated NGS data is mostly heterogeneous and data collected in different sources cannot be easily interoperated. Thanks to Genomic Data Model (GDM), the data can be described in a homogeneous way so the NGS data can be interoperated with different formats. GDM defines the notion of datasets and samples, where in each dataset, the genomic data files have to follow a defined schema and their clinical information have to be in specified metadata files where the general non-genomic features of the sample are explained.\n\nGMQL is a next-generation query language made for querying NGS data that is improving the interaction between biologists and genomic data by offering genomics domain specific operations capable of discovering new biological knowledge by processing huge volumes of NGS data. GMQL requires minimum informatics knowledge and by using a high level language that mixes MapReduce with SQL like characteristics can query NGS data homogeneously by using the GDM model.\n\nThe need of standardization of NGS data to GDM format is important to be able to easily integrate the different types of these data and process them through GMQL. In this thesis\nGMQLImporter, a general Extraction, Transform and Load (ETL) tool, is presented to answer this need; it allows obtaining NGS data from different genomic databanks, and delivering them into standardized GDM files for further GMQL querying. It is sufficiently generic and allows further extensions as easy addition of new manageable types of data formats or databanks. The sources and datasets nowadays present in the GDM repository of the GMQL system are used for testing the designed and developed tool, which allows running either sequential or parallel executions with multithreading.\n\nThe whole GMQL project and therefore GMQLImporter module is developed under Apache License 2.0, which allow the freedom to use the software for any purpose, distribute it, modify it and to distribute modified versions of the software, without any royalties. All the projects developed by the GeCo team at Politecnico di Milano can be found on GitHub https://github.com/DEIB-GECO.\nChapter 2. Background Information\n\n2.1 Next generation sequencing (NGS)\n\nNext generation sequencing (NGS) is a revolutionary research technology for DNA sequencing. With NGS complete human genome sequencing can take less than one day, in comparison with the previous sequencing technology Sanger, which needed almost 10 years to sequence a final version for a human genome. Also as shown in the Figure 2:1 the cost per genome has substantially decreased over time, and the improvement in NGS technologies allows sequencing a whole genome for less than $1,000 U.S.\n\nNGS technologies are increasing the rate of finding answers for fundamental biological and clinical research questions, giving the possibility for comprehensive characterization of genomic and epigenomic landscapes. Questions as how DNA-protein interactions and chromatin structure affect gene activity, how does cancer develop, how genomic or epigenomic traits affect complex diseases such as cancer or diabetes. NGS catalyzes the arrival of personalized and precision medicine by finding sense-making relationships between different\nbiological samples on the same regions based on their reference genome. NGS are used to collect genomic and epigenomic features such as DNA mutations or variations (DNA-seq), transcriptome profiles (RNA-seq), DNA methylations (BS-seq), DNA-protein interactions and chromatin characterizations (ChIP-seq and DNase-seq). Research centers collect the very numerous genomic features produced by NGS raw data processing done by large-scale sequencing projects. Some research centers belong to world-wide consortia such as ENCODE, TCGA, 1000 Genomes Project, Roadmap Epigenomics, and others [1].\n\nDue to the many different laboratories and techniques used in NGS, several formats for the storage of the results exist and cause the data to be highly heterogeneous. Multiple data formats are available for describing NGS experiments such as BED, NARROWPEAK, VCF, SAM, etc [2].\n\n2.2 Genomic Data Model (GDM)\n\nNGS technologies are creating huge amounts of epigenomic and genomic data of different types, and these data are used in tertiary analysis; tertiary analysis focuses in finding meaningful relations on how different regions interact with each other. A new paradigm is proposed for tertiary analysis, and is based in the Genomic Data Model (GDM) [2]. GDM allows describing in a homogeneous way, data that is semantically heterogeneous, in addition enables the interoperability for the data by setting a schema to describe heterogeneous genomic regions data and the incorporation of clinical and experimental metadata.\n\nGDM defines the notion of dataset and samples, and for each sample, the abstraction of genomic region data and metadata. The region data provides representation of DNA and its genomic features, while the metadata describes general properties of the sample.\n\nIn GDM a sample is modeled by 3 attributes (id, R and M). Where id is an integer used as identifier of the sample, R is a set of genomic regions for the sample and M is a set of metadata for the sample. A genomic region (r) is a portion of the genome well defined and identified by 4 values called region coordinates (chr, left, right and strand). chr represents the\nchromosome where the region belongs, left and right are the starting and ending position inside the chromosome, finally strand indicates the direction of reading for the region encoded as ‘+’ (positive), ‘-’ (negative) or ‘*’ (missing: not assigned to a specific strand). The set $R$ is built by pairs $(c, f)$ where $c$ represents the 4 coordinates of the region and $f$ represents the region features as typed attributes, typed attributes can be any of boolean, char, string, integer, long or double and is assumed they have arbitrary names. The schema for the sample region contains a list of attribute names and types for the identifier, coordinates and features. $M$ represents the metadata of the sample region, composed by attribute-value pairs $(a, v)$ assuming values to be strings, attribute names are not necessarily unique as they can be multi-valued by appearing multiple times.\n\nA GDM dataset, in short, is a group of samples sharing a common region schema, including features of the same types; every sample has its unique id inside a dataset and a corresponding metadata with experimental conditions.\n\n2.3 Data sources\n\nMultiple NGS data providers exist, and the main ones used in GMQL are TCGA2BED and ENCODE. Both sources have their data in GDM format and each one have multiple datasets with different schemas between them, in this section TCGA, TCGA2BED and ENCODE project are explained:\n\n2.3.1 TCGA\n\nThe Cancer Genome Atlas (TCGA) [3] is a collaboration project between National Cancer Institute and National Human Genome Research Institute; they produce NGS data and have made available publically genomic changes in 33 types of cancer. Data provided by TCGA have contributed for many cancer studies. By creating a genomic data analysis pipeline, TCGA analyzes human tissues on a very large scale to collect and select genomic alterations.\n2.3.2 TCGA2BED\n\nTCGA to BED format (TCGA2BED) [4] is a software tool for extraction, extension and integration of TCGA genomic data and its clinical metadata. The process of enrichment of the TCGA data includes the addition of annotations from important genomic repositories such as Entrez Gene, HGNC, UCSC and miRBase. The output files are transformed into BED files for the region data and tab-delimited for its metadata. BED format is column-based and contains one line per gene and is GDM friendly also. An open access FTP repository is kept updated with the TCGA2BED generated files.\n\n2.3.3 ENCODE project\n\nEncyclopedia of DNA Elements (ENCODE) [5] is a consortium founded by National Human Genome Research Institute (NHGRI) and receives collaboration of multiple international research groups. Its goal is to generate a comprehensive list of functional human genome elements. A functional element is a segment of the genome that encodes a defined product. ENCODE has performed a large number of NGS studies to map functional elements across the human genome and they provide all their data and protocol descriptions publicly available via their website.\nChapter 3. State of the art\n\n3.1 GenoMetric Query Language (GMQL)\n\nAs NGS data availability is increasing, the ability to process and gather information from these data is necessary: GenoMetric Query Language (GMQL) [6], a next-generation query language, is created to improve the interaction between biologists and NGS data. By offering bioinformatics domain-specific operations, it allows scientists to discover knowledge processing great volume of samples together, including the analysis of their region data and their experimental metadata.\n\nGMQL deals with distances inside the genome: every sample is aligned to a reference genome, and samples with the same reference genome can be processed using these distances in different arithmetic operations between them. GMQL provides a simple yet powerful high level language that combines procedural MapReduce with SQL inspired capabilities with low requirements in informatics knowledge. GMQL changes the paradigm of how NGS data is being managed [7] by providing standard unary operations of SELECT, ORDER, AGGREGATE, PROJECT and MERGE; binary operations of UNION and DIFFERENCE. An on the other hand it provides domain specific operations as: COVER, JOIN and MAP; these operations have a biological interpretation. This paradigm abstraction is proven useful using several biological query examples.\n\nGMQL enables biologists to easily query NGS genomic region data and their metadata, being a pioneer in including metadata in the computation process, and moreover, supports metadata management. Thus metadata is involved in the selection and matching and also is carried along the process, making it available to access it after the execution of the query. Actually GMQL includes available experimental data from ENCODE and TCGA2BED provided in GDM friendly format and therefore ready to be used for querying.\n\nBeing a state of the art tool, GMQL is highly scalable and portable due to the dominant cloud computing paradigms in which is inspired and therefore is well supported in cloud\nexecution. This allows millions of genomic samples to be queried at once with enough abstraction of the language to perform high level processing in a compact way.\n\n3.2 Genome Query Language (GQL)\n\nGenome Query Language (GQL) [7] analyzes NGS data using an SQL extension, they implement their tool by directly connecting it to the sequence reads from a NGS machine, therefore highly specific development is done to operate this kind of data, the processing of raw data is powerful in the sense that the data is non-generalized thus it can be queried with high precision at the cost of identifying the genomic regions of interest. Nowadays the most common way to solve this identification problem is done by developing ad hoc specific tools to fit every type of analysis separately.\n\n3.3 Other solutions\n\nOther tools as The Genome Analysis Toolkit [8], provides a programming framework for analyzing NGS data in SAM format. BEDOPS [9] provides high-performance genomic feature operations focused in BED format, they improve the performance of the tool by file compression. SAMtools [10] provide universal utilities for processing read alignments in Sequence Alignment/Map (SAM) format. Another genomic toolkit is BEDTools [11] allows comparing large datasets in multiple formats, and provides also tools for genomic features manipulation operations.\n\n3.4 Summary\n\nAmong the available tools for genomic research, GMQL allows easier usage by the users, it encapsulates multiple processes commonly done in the field and in comparison with other tools where data selection, annotation retrieval and data interoperation have to be done manually; GMQL is robust enough to be simple to use, allows also the dataset selection over their experimental metadata. GMQL is also independent tool, does not need external scripting and thanks to these features and allows the integration for biologists with no advanced computer programming skills to research in the field of genomics.\nChapter 4. Thesis Goal\n\nThis thesis focuses on the improvement of NGS data analysis by standardizing the acquisition and integration of genomic region data and their clinical metadata into a GDM repository. Specifically in the GMQL project, the need of standardization and integration of NGS data to GDM friendly format is very important for further development and testing. The solution proposed is GMQLImporter, a software that allows acquiring NGS data including their metadata from different genomic databanks and deliver them into standardized GDM datasets ready to use for GMQL querying; it is sufficiently generic to import the nowadays available information in the GDM repository of the GMQL system and allows further extensions as easy additions of managed new data formats or databanks. The designed and implemented software allows incrementally gathering new datasets and iteratively integrating more metadata for better GMQL metadata based querying. For testing the implementation of GMQLImporter, the system will update the datasets already manually loaded in GMQL for the sources of ENCODE and TCGA2BED, where multiple dataset types are found with different downloading procedures and data formats.\nChapter 5. Software design\n\nIn this chapter the general software architecture and workflow are described, database design for storage of the historical progress of the importing process and the design for the configuration of the GMQLImporter tool for importing new genomic data.\n\n5.1 Architecture design\n\nThis thesis requires developing an automatic system to build and keep updated a big integrative repository of genomic data and their metadata publicly available from several specific sources, transforming it into GDM format to be seamlessly used for genomic data processing through GMQL. The main sources of datasets to be imported are the Encyclopedia of DNA Elements (ENCODE) and The Cancer Genome Data into bed format (TCGA2BED). The module has to allow easy addition of future data sources to be imported. This section describes the business rules for the project, also description for key concepts used in GMQLImporter.\n\n5.1.1 Requirement analysis\n\nAs pointed in appendix A “Requirements Analysis for GMQLImporter” the aim is to make easy integrating heterogeneous repository from publicly available genomic data and performing transformation to GDM if needed and standardization for the experimental metadata. As extension for GMQL, GMQLImporter is also developed in Scala programming language. NGS data and their metadata are provided by sources and kept organized in datasets with a variety of formats, to load the datasets inside GMQL, they have to be in a compatible GDM format, have a valid schema for the region data files it contains and one file of metadata for every file of region data. GMQLImporter has to receive the list of sources and their datasets to be imported into GMQLRepository. During the requirement analysis, the initial domain model is collected:\nFigure 5: Initial domain model for GMQLImporter\n\n<table>\n<thead>\n<tr>\n<th>Entity</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Source</strong></td>\n<td>NGS region data and metadata provider.</td>\n</tr>\n<tr>\n<td><strong>Dataset</strong></td>\n<td>Collection of region data and metadata, where all samples respect a given region data schema and file format.</td>\n</tr>\n<tr>\n<td><strong>GMQLRepository</strong></td>\n<td>Interface to connect and import datasets inside GMQL.</td>\n</tr>\n<tr>\n<td><strong>GMQLImporter</strong></td>\n<td>Downloads multiple datasets from different sources. Transforms downloaded datasets into GMQL compatible format (GDM) with standardized metadata. Loads GDM compatible format datasets into the GMQL repository. Tracks historically the status of downloaded and transformed files.</td>\n</tr>\n</tbody>\n</table>\n\nTable 5: Proposed initial entities for GMQLImporter development\n5.1.2 Source and dataset analysis\n\nFor the correct abstraction of the data importing process is needed to specify what is a source and a dataset in the GMQLImporter context, the full explanation is in the appendix B “Specifications for GMQLImporter” and its main specifications are now explained.\n\nA source is considered to be a provider of NGS data, it could be potentially anyone, from ENCODE, TCGA, TCGA2BED, etc. The sources publishes genomic data with experimental metadata, they usually have their data accessible through a unique platform, as ENCODE provides in their website or TCGA2BED in their FTP server. The region data with its metadata is organized into datasets regardless their original format; the same dataset must be always together, from origin to delivery at GMQLRepository. This datasets have to be treated equally along the processing cycle. The general attributes for sources are their name, location and the way data is organized inside their side. For datasets, the important is to know their name, region and metadata files format, and the schema of their region data files.\n\nTCGA2BED and ENCODE provide data in GDM friendly formats, and some of those datasets are used in the development of this thesis. They differ in the downloading process and the metadata gathering. The complete generalization of the sources and dataset performed in this thesis is later explained in the XML design section.\n\n5.1.3 General description for the 3 steps design\n\nFor the correct and easy to understand the process of importing the heterogeneous data, a 3 step general procedure is defined. Inspired in Extraction, Transform and Load (ETL) paradigm the first step is named download and manages the connection and retrieval of datasets from a source, the second step is called transformation and handles, if needed, the conversion into GDM format and then, the modification of metadata to allow its interoperability with datasets from other sources. The final and third step is called loading where the transformed datasets in GDM format are loaded into the destination GDM repository. A full step by step detailed procedure is as follows:\n5.1.3.1 Download\n\nIn this step the connection to the source’s server is carried out, allowing the download of the files that compose the desired dataset. The download has to ensure only needed files are downloaded, in short, not to download the same file 2 times when updating the local copy of the data and to know which files are outdated or the ones that are no longer used in the source’s datasets. For this management, the source should provide ideally with file size, file last modification date and the file’s hash but even with one of those attributes the updating process could be done.\n\nThe hash is the most accurate attribute to know if the local copy is a reflect image of the source’s, then it’s the first priority to check, then the last modification date allow to know if the server side file has been updated but does not allow to certainly know if the downloading of the file is correct. The final attribute to check is the file size, by assuming the source only modifies the files to make them better or more updated, the file size can tell if the file has changed as to have 2 files with the exact size after modification is hard but not impossible, therefore this attribute constitutes the 3rd priority of checking as neither provides sufficient information to check if the file is correctly downloaded or if the version in the server is newer or not. There are multiple protocols that allow file transferring and many ways to distribute data on the server side so non-universal approach for downloading all sources is possible, worth notice that download procedure depends more in the source than the dataset itself, therefore different download methods can be visualized for different sources.\n\n5.1.3.2 Transform\n\nTransformation in this context means to modify the data to be queried seamlessly not caring about the source’s differences, an important step for the correct transformation is done at metadata level, where the metadata names have to be standardized by modifying them if needed. Following this logic, the metadata from different sources could be used equally when the real attribute represented by it is the same or can be related. GMQLImporter gives the general tools for the correct transformation of the region data and their metadata. First ensures the genomic data and their metadata are in a GDM compatible format therefore\nperforms if needed modification of the original sources' files into GDM format, this operations could include full translation from raw data to GDM or extracting compressed containers to name some, but could potentially be any data modification or translation. Once the NGS data and metadata are GDM friendly the transformation process checks for the region data to fulfill the dataset schema and the metadata to be revised and modified if needed for importing it. In the specific case of TCGA2BED they provide the region data and metadata in perfectly compatible GDM format because their project is based on that. For the ENCODE side, they provide region data in GDM friendly format compressed, therefore extraction is needed. The metadata from ENCODE project is provided in several ways, as seen in appendix C “ENCODE Metadata Explanation for GDM” and an special operation has to be done to transform it into GDM. The transformation process as the files provided by the source could be potentially in any format, cannot be universal therefore a generalization is needed, notice that same source could provide different file formats as ENCODE, causing that process to potentially be specific for every different kind of region data and metadata obtained. This generic approach gives GMQLImporter to be potentially capable of managing any kind of genomic data.\n\n5.1.3.3 Load\n\nAs the thesis goal is to import all the processed data into a GDM repository, the final step of this process is to load the data into it. Without performing this loading step, GMQLImporter could be an independent tool for gathering GDM data, but it’s particular use as part of the GMQL project needs to connect with the GMQLRepository, the interface provided by GMQL for dataset importing, to load and make available for GMQL querying the integrated datasets. Potentially could connect to any GDM repository for loading the datasets, therefore the loading step could be specialized to load into another repository.\n\n5.2 XML design\n\nGMQLImporter is designed to receive a configuration XML file with the needed parameters to perform the downloading, transforming and loading steps of the datasets, to provide a\nSoftware design\n\ngeneral approach for the formal creation of this file; an XSD schema file is designed to validate any configuration XML file given as input for the tool. The schema comprehends a root node where general settings and a source list are stored. Sources as seen before, represent NGS data providers which provide those genomic data and experimental metadata divided in datasets, each source contains a list of datasets, each dataset after processing, represents a GDM dataset where every sample has a region data file and a metadata and every sample share the same region data schema. The configuration XSD shown in appendix D “XSD schema for GMQLImporter configuration file”, the file is organized in a tree structure starting from the root node, passing through the sources and ending in the datasets as shown below:\n\n- **root**: contains general settings and a list for sources to import.\n\n - **settings**: general settings for the program execution.\n\n - **base_working_directory**: folder where the importer will use during execution.\n\nFigure 5:2 Root node of the GMQLImporter configuration XSD schema.\n- **download_enabled**: indicates if download process will be executed.\n\n- **transform_enabled**: indicates if transformation process will be executed.\n\n- **load_enabled**: indicates if loading process will be executed.\n\n- **parallel_execution**: indicates if the whole execution is run in single thread processing or multi-thread processing.\n\n- **source_list**: collection of sources to be imported.\n\nFigure 5:3 source node of the GMQLImporter configuration XSD schema.\n• **source**: represents an NGS databank, contains basic information for downloading, transforming and loading process.\n \n - **name**: identification for the source.\n - **url**: address of the source.\n \n - **source_working_directory**: sub directory where the source’s files will be processed.\n \n - **downloader**: indicates the downloading process to be performed to download the samples from this source.\n \n - **transformer**: indicates the transformation process to be performed to change the source samples into GDM compatible files for interoperability.\n \n - **loader**: indicates the responsible for loading the processed data into a GDM repository.\n \n - **download_enabled**: indicates if this source is going to be downloaded from the source.\n \n - **transform_enabled**: indicates if transformation process is executed for this source.\n \n - **load_enabled**: indicates if loading into GDM repository is executed for this source.\n \n - **parameter_list**: collection of parameters for downloading or loading the source.\n\n• **dataset_list**: collection of datasets to import from the source.\n• **dataset**: represents a set of samples that share the same region data schema and the same types of experimental or clinical metadata.\n\n o **name**: identifier for the dataset.\n\n o **dataset_working_directory**: subfolder where the download and transformation of this dataset is performed.\n\n o **schema_url**: address where the schema file can be found.\n\n o **schema_location**: indicates whether the schema is located in FTP, HTTP or LOCAL destination.\n\n o **download_enabled**: indicates if the download process will be performed for this dataset.\nSoftware design\n\n- **transform_enabled**: indicates if the transformation process will be performed for this dataset.\n\n- **load_enabled**: indicates if the loading process will be executed for this dataset.\n\n- **parameter_list**: list of dataset specific parameters for downloading, transforming or loading this dataset.\n\n\n\n- **parameter**: defines specific information for a source or a dataset, this information is useful for downloading, transforming or loading procedures.\n - **key**: is the name for the parameter, its identifier.\n - **value**: parameter information.\n - **description**: explains what the parameter is used for.\n - **type**: optional tag for the parameter.\n\n5.3 Database design\n\nA really important requirement for the solution is to maintain the genomic repository updated and provide historical status for every file and to know when there are new files or\nones that are obsolete. The database for GMQLImporter allows knowing the status for every file, on every dataset, on every source ever imported through GMQLImporter. It is possible to know whether a source was downloaded or transformed, also it’s belonging datasets and all the files inside the dataset. The full database design description is in the appendix E “Database design for GMQLImporter” and the main components are:\n\n5.3.1 Sources, datasets and files\nTo know exactly the status and which files were provided by the source in a given execution, a general structure for sources, datasets and files is contained inside the GMQLImporter’s database, the possibilities to know how many files are provided on the source, how many were downloaded, transformed or loaded already. The history for every file, to know when they were updated is also contained. With this implementation, it is possible to know the status of the files inside the repository at any given point in time, with the correspondent details of the files at that time. GMQLImporter can give important feedback for every execution so the user can know easily the status of the repository.\n\n5.3.2 Statistics\nDuring the execution of GMQLImporter some important information is collected, such as the number of available files for download from the source, the amount of failed or replaced files, the correctly transformed ones and the also the wrong ones. In every run the total number of files available to download or transformed is stored, together with the number of correct and failed ones, after the number of files that do not fit the dataset’s schema. GMQLImporter can provide this statistical historical data as it keeps track of it in the database.\n\n5.3.3 Configuration\nOn every run, the configuration XML file could differ and give a different output or substantial change to the status of the repository, therefore the information provided in the configuration file is stored for every run to know what the desired actions to perform in\nGMQLImporter were. As the configuration XML schema, is needed to store the general settings information, the specifications for every source involved and their datasets.\n\n5.3.4 Database model\n\nHere the main features of the database model are explained, most important indices and methods:\n\nFigure 5:6 database model for GMQLImporter.\nIn this model, the sources with their datasets and files are represented by the tables Sources, Datasets and Files; the configurations for the execution are saved in tables Runs, RunSourceParameters and RunDatasetParameters where the configuration XML file parameters are saved distributed in the same way the XSD schema defines. Statistics are carried out using tables of RunFiles and RunDatasetLog where information is stored during runtime to let the user know the total available files to download and also failed, outdated and updated files during the execution.\n\nTo know the status of any file, 4 statuses are defined for a file:\n\n- **Updated**: The file download/transformation is correctly performed in the local repository as it was in the server the last time the dataset where the file belongs was downloaded.\n\n- **Failed**: The file download/transformation failed and the file may not be valid, in this case the file is marked as failed.\n\n- **Outdated**: The file was removed from the server; this causes the file to exist locally but not remotely.\n\n- **Compare**: Auxiliary status used to know which files do not exist anymore on the server, this status is meant to be used while the program is executing.\n\nThe following diagram shows the transitions of different file statuses and after every function inside is explained.\nThe main database methods include:\n\n- **MarkToCompare**: by receiving a dataset, the database changes the status of every file in the dataset as to compare, this method is used to notice which files are no longer in the server side and have to be marked as outdated in the local copy.\n\n- **MarkAsUpdated**: indicates the file was correctly downloaded or transformed and it is ready for the next step that could be transformation or loading.\n\n- **MarkAsFailed**: when trying to download or transform a file, if the procedure fails, the file has to be excluded from further processing and thus it is marked as failed.\n\n- **MarkAsOutdated**: once the whole dataset is downloaded or transformed this procedure allows finding the files that no longer exist in the remote server, and marks those local files as outdated. These files are no longer used in transformation or loading procedures.\nChapter 6. Implementation\n\nThe GMQLImporter module uses several technologies and frameworks. The project is mainly developed in Scala programming language. It is used to import GDM processed data into GMQL through GMQLRepository, the interface used by GMQL to load the datasets. Before the implementation of GMQLImporter, the importing processes for GMQL were done by running specifically developed scripts for TCGA2BED and ENCODE sources.\n\nAs defined in the design, the overall importing process is decomposed into 3 sequential steps. GMQLImporter has to tolerate all the possible faults from multiple technologies involved in the process such as internet loss or missing files in the source and also needs to provide enough feedback for the user to know the actual status of the repository. This chapter explains these processes in detail as implemented in GMQLImporter.\n\n6.1 Downloader\n\nThe first step is downloading the files from the source’s server, and as discussed in the design, multiple download methods can exist depending on different servers. The implementation for downloading is done by using a generalization of the process of download for any source. The generalization includes the ability to download by source, where every source has its datasets, only datasets that are marked to download will be downloaded. During the download, the downloader has to feed the database with the files it is checking to download and downloading, indicating if the file is correctly downloaded, outdated, updated or failed. Also the generalization was implemented with the possibility of downloading the failed files, in this way not the whole downloading process has to be checked again and can download just the missing files.\n\nThe implementation done in this thesis comprehends the implementations of FTPDownloader and ENCODEDownloader, the first one goes over folders provided by a FTP server, finds folders to download by using regular expressions and inside those folders uses regular expressions to know which files to download. The FTPDownloader is used to download\nImplementation\n\nTCGA2BED datasets and could be used in many other FTP servers. On the other side, ENCODEDownloader is used specifically for ENCODE data, it uses the provided HTTP batch download by ENCODE discussed in appendix C “ENCODE Metadata Explanation for GDM” and by specifying a set of rules to generate an specific URL, allows to get an index file with the references to download every region data file with its metadata from ENCODE. These 2 different implementations follow the general procedures of downloading files and downloading failed ones.\n\n6.2 Transformation\n\nThe transformation step consists in turn NGS data into GDM friendly format and to modify if needed the metadata provided. In this process, if the data is not provided as needed for the GDM repository, a transformation of the files is needed. The transformation process is done different for different types of files, therefore for every type of files have to exist a transformation definition to turn it into GDM. The data transformers have to provide the ability to transform any specific file and to know how many files are derived from it, to allow the insertion in the database to know the origin of every file that is going to be in the repository.\n\nAfter getting all region data and metadata in GDM friendly formats, it checks the region data files to know if they fit the dataset schema, then to make metadata easily interoperable changes metadata names as indicated in the configuration. Before finishing the transformation step, the metadata names contained for the experiment have to be transformed if needed to be valid as Java identifier for its correct function in GMQL. Any transformer that follows the general procedure can be added later in the GMQL Importer module.\n\n6.3 Loader\n\nGMQL provides an interface for loading data into it, it is GMQLRepository and GMQL Importer has to communicate with it. By giving the GMQL user name to load a source’s datasets it checks the consistency of the dataset by checking it has a schema defined and that every region data file has its respective metadata. As by business rules of GMQL, a dataset cannot have added files once is already created, if this happens, GMQL Importer allows the user to\nconfirm the choice to delete the previous one to be replaced, or to change the name of the updated dataset using the configuration XML file. This process is done by the functions provided by GMQLRepository as check if the dataset already exists, delete a dataset and to load dataset into GMQL.\n\n6.4 Fault tolerance\n\nDue to the mix of technologies, there are many faults that can affect the GMQLImporter functioning. Internet connection is one of the possible problems, it may cause some file downloads to fail and this problem is solved by retrying on every failed file and giving proper feedback to the user. Some files can be provided by non-functioning links and GMQLImporter has to deal with it, if missing region data or metadata, the whole sample must be discarded from the importing process and give feedback to the user. Files also can be filtered locally to ensure correctness and completeness if the source provides the data with anomalies, this includes as example, metadata filtering for ENCODE files since the batch download in some attributes does not filter correctly. Also if files on a dataset do not fit to the schema, this is notified to the user.\n\n6.5 Logging\n\nGMQLImporter provides constant feedback to the user both by console and by file logging. These logs allow the user to know the updated status while GMQLImporter is running and also to search over the operations done in the run. Also at the end of each run, a general statistics report for the run is given for the different sources and datasets.\n\nEvery GMQLImporter module defines its log, as the downloaders, importer, transformers and loaders. Full description for the implemented logging is on appendix F “GMQLImporter console & file logging”.\n\nThe logging structure for the messages has 4 levels: DEBUG, INFO, WARN and ERROR. The messages are given in hierarchical order depending in the process being run, this means first messages correspond to general process then download messages for each source and da-\ntaset, then transformation and finally loading. DEBUG messages are used for checking the correct working and fine grained status in the run, example of this are checking if the internet connection is active, to know also the changes done in metadata files, notify if a folder is created, among others. INFO messages indicates which action is being done and when it finishes, as example notifies when a file is being downloaded or transformed and when the process is done, also gives information about the configuration for the user to check whether is correct. WARN messages tell the user if something is not correct but the program still can handle the processing; it can be a file that does not match the schema or if the local files referenced do not exist. ERROR is used to notify a file download failed after retrying, if a link is not working or if the given parameters are causing problems and the system cannot work properly.\n\nDifferent information is shown on console log and on file log throughout the execution. The console log is designed to let the user know the overall status, including messages as ERROR, WARN and INFO. The file logging is designed for debugging of the GMQLImporter functioning, it gives sufficient information to know where the program failed if so and to generate a fast identification of the problem.\n\n6.6 Technologies used\n\nMany technologies are used in the development of GMQLImporter, the main ones are explained below:\n\n6.6.1 Scala\n\nScala is a highly scalable programming language that combines both functional and object oriented languages. It runs on the Java Virtual Machine (JVM) by compiling Scala to Java bytecode, so Scala and Java can be freely mixed. Scala allows a much faster development than plain Java with the same performance. Conceptually Scala is a pure object oriented\nlanguage, all variables and values are objects and any operation is a method. Allows easy transition to a functional style programming and is backed up by a huge range of libraries, frameworks and IDEs. Scala is maintained by the Scala community using GitHub for code management.\n\n6.6.2 SLF4J + log4j\n\nSimple Logging Facade for Java (SLF4J) is a Java logging API that serves as abstraction for multiple logging frameworks, such as the one used in GMQLImporter, log4j. This logger is set up at runtime and allows the communication in the console, and also straight to a file. The logging framework provides a level oriented messaging with the following levels (in decreasing priority order) ERROR, WARN, INFO, DEBUG or TRACE; ERROR is meant to communicate wrong functioning of the process, WARN is used to notice the user that something is not completely correct but the program can still work, INFO is to communicate general message feedback to the user in the application, DEBUG is used to describe the internal steps taken in the program for developers to have extra information during the program run, and TRACE is to fine grain the debugging by communicating more details to developers. The logger has the option to set up a threshold level, this allows to limit information shown to the user and to easily create multiple types of log, such as in GMQLImporter where log4j is used to show just up to INFO to the user, and DEBUG for developers.\n\n6.6.3 Maven\n\nMaven is a tool used mainly in Java projects for build automation; it describes how the software has to be built, including dependencies used inside the project and how those components are built together. It uses an architecture based in plugins, and provides a full plugin catalog for easily using them inside a project. The full configuration relies in a Project Object Model (POM) XML file. The full development of GMQLImporter is done using Maven, causing the project to be easy to expand, as the programming environment is easily portable.\n6.6.4 H2Database\n\nH2Database is a lightweight database management system that runs embedded in the program code, this means it needs no installation and as it runs in Java over the JVM, is easily portable between many platforms. In GMQLImporter the database configured as text based database, the database allows a subset of SQL queries. Is a complete transactional database and provide SQL injection protection, encryption password by using SHA-256 and communication security as SSL or TLS connections.\nChapter 7. Evaluation\n\nFor the evaluation phase, the datasets that are at present already loaded into GMQL-Repository are chosen for testing the GMQLImporter module. In this chapter, the essential features on the creation of the configuration XML using the previously defined schema are explained. After download, transform and load processes are discussed and finally a summary of the overall results in the execution of the module is presented. The execution of GMQLImporter was done using 32 cores with 2 threads each Intel(R) Xeon(R) CPU E5-2650 0 @ 2.00GHz with 378 GB System memory with an internet connection tested between 605.39 and 749.43 Mbit/s during the download process, the test was done in parallel mode and also sequentially.\n\n7.1 Configuration XML creation\n\nThe whole creation process is detailed in appendix G “Creation of XML configuration file for GMQLImporter” and here, the main settings used for evaluation are explained. The included sources to be imported are 2 sources already included in GMQL and the new imported datasets will be the update of them, the sources are TCGA2BED and ENCODE. Following the schema for the configuration file, the datasets desired to load into GMQL are:\n\n<table>\n<thead>\n<tr>\n<th>TCGA2BED</th>\n<th>ENCODE</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>cnv</td>\n<td>HG19_broadPeak</td>\n</tr>\n<tr>\n<td>dnametylation</td>\n<td>HG19_narrowPeak</td>\n</tr>\n<tr>\n<td>dnaseq</td>\n<td>GRCh38_broadPeak</td>\n</tr>\n<tr>\n<td>mirnaseq_isoform</td>\n<td>GRCh38_narrowPeak</td>\n</tr>\n<tr>\n<td>mirnaseq_mirna</td>\n<td></td>\n</tr>\n<tr>\n<td>rnaseq_exon</td>\n<td></td>\n</tr>\n<tr>\n<td>rnaseq_gene</td>\n<td></td>\n</tr>\n<tr>\n<td>rnaseq_spljxn</td>\n<td></td>\n</tr>\n<tr>\n<td>rnaseqv2_exon</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nTable 7.1: Datasets from ENCODE and TCGA2BED to be imported.\n\n<table>\n<thead>\n<tr>\n<th>Dataset</th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>rnaseqv2_gene</td>\n<td></td>\n</tr>\n<tr>\n<td>rnaseqv2_isoform</td>\n<td></td>\n</tr>\n<tr>\n<td>rnaseqv2_spljxn</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n7.2 Changes of implementation and adaptation\n\nThe versatility of the GMQLImporter was also proven during the development, as the requirements changed constantly, the XML configuration file provided enough freedom to give multiple parameters for the correct download and transformation of the datasets. The presented module is robust with fault tolerance. Also the 3 steps of download, transform and load gave a correct abstraction for the problem proposed and allowed the generalization of the Importing process.\n\n7.3 Parallel run\n\nTo evaluate GMQLImporter it is tested using both parallel and non-parallel executions, as the process includes multiple downloads and file processing in a very tidy way, the overall process is highly parallelizable. The download or transformation of multiple datasets at the same time is enabled for testing the parallel execution of GMQLImporter and it is activated or deactivated in the XML configuration file. The main variable to compare is the time used for the complete process of downloading and transforming the data, both runs are executed in different times and using different folders to isolate the processes.\n\n7.4 Results\n\nThe imported data results are given in the following table specifying comparable times (expressed as HH:MM:SS) for download and transform, using parallel download and using sequential download:\n<table>\n<thead>\n<tr>\n<th>Dataset</th>\n<th>Nº of samples</th>\n<th>Size</th>\n<th>Download Parallel</th>\n<th>Download sequentially</th>\n<th>Transform parallel</th>\n<th>Transform sequentially</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>cv</td>\n<td>22632</td>\n<td>869 MB</td>\n<td>19:53:17</td>\n<td>75:57:58</td>\n<td>02:59:47</td>\n<td>01:02:27</td>\n</tr>\n<tr>\n<td>dnaseq</td>\n<td>6914</td>\n<td>305 MB</td>\n<td>19:52:54</td>\n<td>75:57:06</td>\n<td>00:58:09</td>\n<td>00:18:27</td>\n</tr>\n<tr>\n<td>miranseq_mirna</td>\n<td>9909</td>\n<td>775 MB</td>\n<td>19:52:56</td>\n<td>76:18:21</td>\n<td>01:28:03</td>\n<td>00:26:51</td>\n</tr>\n<tr>\n<td>rnaseq_exon</td>\n<td>3675</td>\n<td>46 GB</td>\n<td>18:01:29</td>\n<td>72:35:19</td>\n<td>01:38:35</td>\n<td>00:40:39</td>\n</tr>\n<tr>\n<td>rnaseq_gene</td>\n<td>3675</td>\n<td>5 GB</td>\n<td>18:59:35</td>\n<td>72:37:32</td>\n<td>00:57:03</td>\n<td>00:14:56</td>\n</tr>\n<tr>\n<td>rnaseq_spljxn</td>\n<td>3675</td>\n<td>43 GB</td>\n<td>19:05:05</td>\n<td>72:58:50</td>\n<td>01:37:14</td>\n<td>00:40:57</td>\n</tr>\n<tr>\n<td>rnaseqv2_exon</td>\n<td>9825</td>\n<td>119 GB</td>\n<td>19:54:09</td>\n<td>76:01:29</td>\n<td>03:19:26</td>\n<td>01:46:39</td>\n</tr>\n<tr>\n<td>rnaseqv2_gene</td>\n<td>9825</td>\n<td>21 GB</td>\n<td>19:53:06</td>\n<td>75:58:17</td>\n<td>02:24:43</td>\n<td>00:43:14</td>\n</tr>\n<tr>\n<td>rnaseqv2_isoform</td>\n<td>9825</td>\n<td>50 GB</td>\n<td>19:53:22</td>\n<td>75:59:30</td>\n<td>02:32:07</td>\n<td>01:02:20</td>\n</tr>\n<tr>\n<td>rnaseqv2_spljxn</td>\n<td>9825</td>\n<td>110 GB</td>\n<td>19:54:08</td>\n<td>76:02:03</td>\n<td>03:16:03</td>\n<td>00:41:23</td>\n</tr>\n</tbody>\n</table>\nTable 7-2: execution times in with and without parallelization for each dataset.\n\n<table>\n<thead>\n<tr>\n<th>Dataset</th>\n<th>Size</th>\n<th>Time 1</th>\n<th>Time 2</th>\n<th>Time 3</th>\n<th>Time 4</th>\n<th>Time 5</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>HG19_broadPeak</td>\n<td>1534</td>\n<td>02:47:45</td>\n<td>02:19:53</td>\n<td>01:19:24</td>\n<td>00:27:11</td>\n<td></td>\n</tr>\n<tr>\n<td>HG19_narrowPeak</td>\n<td>9783</td>\n<td>19:17:04</td>\n<td>20:03:15</td>\n<td>03:41:39</td>\n<td>02:07:12</td>\n<td></td>\n</tr>\n<tr>\n<td>GRCh38_broadPeak</td>\n<td>367</td>\n<td>00:36:44</td>\n<td>00:37:52</td>\n<td>00:11:29</td>\n<td>00:04:02</td>\n<td></td>\n</tr>\n<tr>\n<td>GRCh38_narrowPeak</td>\n<td>9415</td>\n<td>19:12:24</td>\n<td>18:16:22</td>\n<td>03:48:32</td>\n<td>02:12:57</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nIt is worth to mention the times on TCGA2BED datasets for download always have similar times for download as the download is done by traversing the folder structure in the FTP repository; this causes all the datasets to start the downloading process on the first folder visited and to end in the last folder to visit.\n\nFor calculating the total download time sequentially, the maximum time spent for a dataset download in TCGA2BED (76:19:14) is considered as the total time for downloading that source while in ENCODE, the sum of all download times for each dataset is the total time for downloading the source (41:54:22); giving a total time for download sequentially of 118:13:36. Downloading in parallel for TCGA2BED speeds up every dataset as 1 process takes care of traversing the repository and multiple sub processes download the files; for ENCODE in parallel download the speed up is also substantial as all datasets are downloaded at the same time instead of waiting sequentially. For the total time of download in parallel, the maximum time for a dataset download is considered as the total time for downloading all the sources, giving a total time for parallel download of 19:55:28.\n\nAs for the transformation time when done sequentially, the total transformation time of all sources is equal to the sum of every transformation time for each dataset thus the total transformation time sequentially is 16:20:35. When transformation is done in parallel, multiple dataset are processed at the same time, therefore sub processes share the local resources causing the time for individual datasets to increase; but as for parallel execution, the\ntotal transformation time is equal to the maximum transformation time among the datasets which is 04:44:48 and therefore the parallel execution speeds up the overall transformation process.\n\nAll these datasets were loaded into GMQL in a total time of 11:43:44. The loading process is always done sequentially.\nChapter 8. Conclusion and future work\n\nGMQLImporter by using correspondent generalization for the process of retrieving genomic data and metadata from multiple sources, standardize them towards their integration, and importing them into a GDM repository for their comprehensive processing through GMQL, effectively accomplishes these tasks and allows easy further development for the inclusion of new data sources that may be added later.\n\nGMQLImporter solves the problem of supporting the automated gathering of genomic data with their respective metadata into a GDM repository, providing the correspondent feedback to the user. Thus, the process of importing distributed heterogeneous data for their integrated GMQL processing is highly automated and no complex supervision is needed.\n\nAs the presented results show, the use of parallel execution speeds up substantially the downloading process by taking less than a fifth of the time for the sequential download; and the transformation process done in parallel takes less than a third of the time for sequential transformation. These times can be improved even more by optimizing the parallelization processes as doing transformation in parallel to handle multiple files for each dataset at the same time.\n\nAs part of future work, new downloaders and transformers will be developed; also further analysis of clinical metadata to allow a complete interoperation between data from different sources will be done.\nReferences\n\n\nAppendix A. Requirements Analysis for GMQLImporter\n\nA.1. Project objective\n\nThis project requires developing an automatic system to build and keep updated a big integrative repository of genomic data and their metadata publicly available from several specific sources, transform them into GDM format to be seamlessly used for genomic data processing through GMQL.\n\nA.2. Project summary\n\nThe aim is to make easy integrating heterogeneous genomic data and performing complex processing on them. GMQL is currently being developed in Scala programming language and for this module to be an extension; Scala is also used in the development of GMQLImporter module. Data and their metadata are provided by Sources and kept organized in Datasets with a variety of formats, to load the data inside GMQL, these have to be in a compatible format, have a valid schema file and one file of metadata for every file of region data; the GDM is being used in the GMQL project for region data and metadata representation. The main sources of datasets to be imported into GMQL are the Encyclopedia of DNA Elements (ENCODE) and The Cancer Genome Data into bed format (TCGA2BED). The module has to allow easy addition of future data sources to be imported.\n\nA.3. Requirements list\n\nDuring the analysis, a starting point for the overall process was set by defining a list of requirements to be accomplished in the software implementation:\nA.4. Heterogeneous genomic data and metadata download from multiple different sources\n\n- The software must support different downloading protocols.\n- Flexibility to allow downloading from different sources and therefore it has to adapt to remote source data organization.\n- Specific parameters for download are defined by source and/or dataset.\n\nA.5. Genomic data and metadata transformation towards data integration\n\n- Organize region data and metadata according to the Genomic Data Model (GDM), this may include processes as:\n - Extract compressed files.\n - Obtain metadata from different files.\n - Define or change a region data schema.\n- Modify/standardize data/metadata attribute names, contents or format.\n\nA.6. Load downloaded and transformed data and metadata into an integrative GDM repository\n\n- Connect to the repository by using provided API according to the rules defined in the repository.\n- Create, delete and update datasets into the repository.\n\nA.7. Automatic checking, monitoring and recording quantitatively\n• Keep track of the processes done in region data and metadata from its download to its loading into the repository.\n\n• Control automatically when possible the correctness and completeness of the steps performed to the data and metadata.\n\n• Provide quantitative summary descriptions of the process steps.\n\n• Support in efficient and feasible way the easy evaluation of correctness and completeness on each step.\n\nA.8. Support data and metadata update and extension\n\n• The software has to allow easy extension of the processes previously performed over the data and metadata for further processing or for aggregation of similar sources, datasets, region data, metadata or other files.\n\n• Newer versions of the data with their respective metadata provided by the sources must be easily updated in future executions. As different sources release new information at different pace, the software must check for updates in the origin source and add the new data and metadata to the process.\n\n• The main application of the development must be done for the sources of TCGA2BED and ENCODE and the loading process into GMQL repository.\n\nA.9. Initial domain model\n<table>\n<thead>\n<tr>\n<th>Entity</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Source</td>\n<td>NGS region data and metadata provider.</td>\n</tr>\n<tr>\n<td>Dataset</td>\n<td>Collection of region data and metadata, where all samples respect a given region data schema.</td>\n</tr>\n<tr>\n<td>GMQLRepository</td>\n<td>Interface to connect and import datasets inside GMQL.</td>\n</tr>\n<tr>\n<td>GMQLImporter</td>\n<td>Downloads multiple datasets from different sources. Transforms downloaded datasets into GMQL compatible format (GDM) with standardized metadata. Loads GDM compatible format datasets into the GMQLRepository. Tracks historically the status of downloaded and transformed files.</td>\n</tr>\n</tbody>\n</table>\n### A.10. Key actors and tasks\n\n<table>\n<thead>\n<tr>\n<th>Actor</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Source</td>\n<td>Provider of the datasets used in the GMQLRepository.</td>\n</tr>\n<tr>\n<td>GMQLRepository</td>\n<td>Module of GMQL project that has the datasets to be queried.</td>\n</tr>\n<tr>\n<td>GMQLImporter</td>\n<td>Module of GMQL project that obtains datasets from sources and transforms their region data and metadata into GDM to be loaded inside the GMQLRepository. Keeps track of downloaded, transformed and loaded files in order to keep the GMQLRepository updated and non-redundant.</td>\n</tr>\n<tr>\n<td>Administrator</td>\n<td>Configures the GMQLImporter based on his knowledge of the sources and their datasets</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Task</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Download</td>\n<td>Gets datasets from a source, has to keep the files updated.</td>\n</tr>\n<tr>\n<td>Transform</td>\n<td>Transforms and/or process data and metadata into GDM format to be imported in GMQLRepository, has to keep the files updated.</td>\n</tr>\n<tr>\n<td>Load</td>\n<td>Inserts into GMQLRepository GDM compatible datasets with their corresponding schema.</td>\n</tr>\n</tbody>\n</table>\n\n### A.11.\nA.12. Use cases\n\nA.13. Download\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Description</td>\n<td>By giving description of a source and specifying types of datasets of interest, the application downloads those datasets and puts them ordered into a local folder.</td>\n</tr>\n<tr>\n<td>Preconditions</td>\n<td>The source and its datasets have to exist. The source downloading procedure has to be defined previously.</td>\n</tr>\n<tr>\n<td>Post conditions</td>\n<td>There is a local copy of the files in the source ordered in separate folders by dataset.</td>\n</tr>\n<tr>\n<td>Nonfunctional</td>\n<td>Is needed to track of downloaded files, and when download only download files to be updated if already have been downloaded. Keep the user notified about the loading process.</td>\n</tr>\n<tr>\n<td>Requirements</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nA.14. Transform\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Transform datasets from source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Description</td>\n<td>By giving description of a source and specifying datasets of interest, the system if needed applies a specific transformation for the files to be in GDM format for further data or metadata standardization.</td>\n</tr>\n<tr>\n<td>Preconditions</td>\n<td>The source and its datasets have to be already downloaded and their transformation procedure has to be defined previously.</td>\n</tr>\n<tr>\n<td>Post conditions</td>\n<td>There is a transformed copy of the source’s original datasets in the destination folder in GDM compatible format.</td>\n</tr>\n<tr>\n<td>Nonfunctional</td>\n<td>Is needed to track of the files to know their status. Keep the user notified about the loading process.</td>\n</tr>\n</tbody>\n</table>\n\nA.15.\n### A.16. Load\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Load datasets from source</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Description</td>\n<td>By giving description of a source and specifying datasets of interest, the application loads into GMQLRepository those datasets with their respective schema file.</td>\n</tr>\n<tr>\n<td>Preconditions</td>\n<td>The source and its datasets files have to be in a GDM compatible format with region data and metadata plus the schema file.</td>\n</tr>\n<tr>\n<td>Post conditions</td>\n<td>The datasets are available for querying inside GMQL.</td>\n</tr>\n<tr>\n<td>Nonfunctional Re-</td>\n<td>Keep the user notified about the loading process.</td>\n</tr>\n<tr>\n<td>quirements</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n![Diagram of Load process]\nA.17. Check historical statistics\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Check historical statistics</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Description</td>\n<td>Shows to the administrator the statistics of files tracked while downloading and transforming datasets.</td>\n</tr>\n<tr>\n<td>Preconditions</td>\n<td>Files are tracked already in download or transform steps, indicating how many files have been downloaded or transformed and information about the problems had in the process.</td>\n</tr>\n<tr>\n<td>Post conditions</td>\n<td></td>\n</tr>\n<tr>\n<td>Nonfunctional Requirements</td>\n<td>Has to provide enough information to understand the status of the GMQLRepository, downloaded and transformed files.</td>\n</tr>\n</tbody>\n</table>\nAppendix B. Specifications for GMQLImporter\n\nB.1. Specifications Summary\n\nThis appendix is a continuation of appendix A “Requirements Analysis for GMQLImporter”. Shows how data is downloaded from different Sources, how the data is transformed into a GDM compatible format and how it is loaded for each Source. The sources explained are TCGA2BED and ENCODE. After explaining the process, a generalization of the sources and their procedures is presented, followed by a new general domain model of the GMQLImporter module.\n\nB.2. Requirements Analysis by Source\n\nThis section explains how the data is acquired; specifies the data location, retrieval methods, and how to import them into GMQLRepository. For inserting files into the repository, they have to be in GDM format, separated by experiment every data and metadata file. Also a schema file is required to define the file format.\n\nB.3. TCGA2BED\n\nContains data from TCGA converted in BED format, for experiments of DNA-Seq, RNA-Seq (V1 and V2), DNA-Methylation, miRNA-Seq and CNV. Data is located inside a FTP repository where original (TCGA) and converted (TCGA2BED) files are stored. Inside the converted directory the files are grouped by tumor name into folders with their respective tumor tag, inside every tumor folder, the files are again grouped by experiment type into folders with the experiment name. Each of those folders contains: the dataset schema, file with total number of files in the folder, file with md5 checksum for every file in the folder, region files and metadata files. The region data files are presented in BED format with its associated metadata, each experiment has a .bed and a .bed.meta file. Inside GMQLRepository the\nTCGA2BED files should be grouped by experiment type and not by tumor name. Files are downloaded from the source; grouped by experiment type and then the schema file is added, after this if needed, metadata can be modified before being imported into GMQLRepository.\n\nB.4. ENCODE\n\nContains data for a great amount of experiments and data types, data is provided by HTTP access using a direct link for downloading every file, the file format depends on the type of experiment. ENCODE allows 3 types of metadata download as explained in appendix C “ENCODE metadata explanation for GDM”. To load ENCODE data inside GMQLRepository is necessary to download every data file, initially the GMQLImporter project aims to integrate BED broadpeak and BED narrowpeak format types of ENCODE, so bed files have to be downloaded, they are provided in compressed containers (.gz) so extraction after downloading is needed. For the creation of metadata files is necessary to download the metadata and then create for every data file, a respective metadata file by merging the rows from both metadata files or extracting the metadata from JSON files downloaded. Data and metadata have to be put together with the dataset schema and then they are ready to be imported into the GMQLRepository.\n\nB.5. Model Generalization\n\nThinking in a complete generic model to describe all the available sources and datasets is not possible, but the main operations needed to achieve correct integration are possible.\n\nFor transforming procedure, initially complex data file transformation is not needed, but in the future could be, and this problem has to be addressed. TCGA2BED has the files just as GMQLRepository needs them just not in the order it is desired. ENCODE data files come in .gz containers that have to be extracted, their metadata has to be separated into several files, and source metadata files may be in different formats. At the loading stage, GMQLRepository needs to have the following files for each dataset:\nSpecifications for GMQLImporter\n\n- Schema file describing region data format.\n- Set of region data files in GDM compatible format.\n- Set of metadata with 1 metadata file for each region data file.\n\nLoading procedure in the development is by using the GMQLRepository interface provided by GMQL project, but any other repository could be used and that flexibility also has to be addressed.\n\nB.6. General Domain Model\n\nThe GMQLImporter module has been divided by the 3 basic operations to be performed in the import process; those ones are download, transform and load. For the transformation procedure, although similarities could be found, because of the variety of different NGS formats and the need of transform those to GDM format, GDMTransformer represents a type of transformation procedure, where a particular set of operations can be defined for each source to transform original files into GDM friendly ones. Same as for downloading procedure, no unique generic way to download datasets from sources is feasible so GMQLDownloader represents a type of downloading procedure, where any particular implementation for downloading different sources can be implemented. The new domain model is the following:\nB.7. Sequence diagrams\n\nIn this section the main processes for GMQLImporter are defined and also the details for the interaction sequences between the different modules involved in the software execution. The diagrams explain the main desired behavior:\nSpecifications for GMQLImporter\n\n1. Administrator\n - Main Program\n - give configuration XML\n - If(XML is not valid)\n - return\n - Else\n - load XML configuration\n - set database\n - check if database is created\n - create database\n - If(database does not exist)\n - return\n - save configurations\n - return\n - Foreach source in configurations\n - Download process\n - Transform process\n - Load process\n - return\nThe main program loads the configuration from the XML file, with this configuration, the program recreates the sources requested and the datasets for every source. With this structure, iterates on every source for download, transform and load. For the download part, as discussed before, specific operations must be done separately for TCGA2BED and ENCODE, therefore the process of download happens completely separated between both sources. The main program by the giving configurations has to select the needed implementation for “Download process” and “Transform process”. Load process is done always by using GMQLLoader but may be extended to use another GDM repository. The transformation process has a general transformation part and a specific transformation part; in the specific one the files have to be transformed to GDM friendly format. Whilst in the general part, the region data schema and the metadata files are checked for correctness. The next steps shown are subsections of the overall execution and therefore assume the main program’s load of the XML configuration file and the existence of the FileDatabase.\nSpecifications for GMQLImporter\n\nB.8.\nSpecifications for GMQLImporter\n\n1. **Download ENCODE**\n - **Foreach dataset**\n - markToCompare\n - return\n - generate download URL\n - download metadata.tsv\n - markAsUpdated metadata.tsv\n - return\n - **Foreach line in metadata.tsv**\n - extract file URL\n - checkIfUpdate\n - return\n - **If(update)**\n - download file (retries up to 3 times)\n - return\n - generate JSON URL\n - download JSON (retries up to 3 times)\n - return\n - **If(file & JSON downloaded correctly)**\n - markAsUpdated (both)\n - return\n - **Else**\n - markAsFailed (both)\n - return\n - markAsOutdated\n - return\nSpecifications for GMQLImport\nAppendix C. ENCODE Metadata Explanation for GDM\n\nC.1. Metadata Organization\n\nFor the ENCODE project, the metadata for every experiment is distributed in a tree structure of entities, the root node is the experiment entity where the immediate metadata for the experiment is found, this includes metadata such as \"biosample_type\", \"date_released\", \"replication_type\" and \"status\". Also in the root, non-immediate metadata is referenced, this comprehends metadata like \"files\", \"award\" and \"replicates\". The tree created is non-cyclical therefore exists a unique way of getting the information starting from the root. The root node contains 48 branches, 19 of them are leaves (immediate metadata referred as plain text) of the tree, 3 are other complex entities that represent by themselves a complete tree structure and the remaining 26 branches are arrays that can contain either leaves or other complex types.\n\nC.2. Metadata Acquisition\n\nDownloading metadata from ENCODE is a straightforward action that defines a metadata filter for the experiment files to download; this filter can select any metadata as criteria such as Genome Assembly, File Format, Output Type, Biosample Life Stage, among others.\n\nENCODE’s model has as root level the experiments, and all the experimental metadata is linked to this entity as explained before.\n\nFrom the ENCODE project metadata can be downloaded in 3 different ways (where each one gives different amount and/or type of metadata).\n\nC.3. Metadata.tsv\nENCODE defines this metadata.tsv file as a pre-defined set of metadata meant to be downloaded using their Batch Download method, it contains 48 fields of metadata associated to every region data file. The file defines a table where every row describes a sample file and every column gives metadata about them. The metadata contained is gathered from different nodes of the metadata tree and then the names are changed to the preferred term on ENCODE’s ontology for the field name.\n\nTo download the metadata.tsv, the creation of a URL is needed. The URL creation is done in 3 blocks: prefix, filter and postfix.\n\nThe prefix is always the same:\n\n```\nhttps://www.encodeproject.org/metadata/\n```\n\nThe filter is created by setting a conjunction of metadata filters, an example that gets the metadata for files related to experiment, where the files are bed narrowpeak and limits the files to be just the first 2 of the list:\n\n```\ntype=Experiment&limit=2&files.file_type=bed+narrowPeak\n```\n\nThe postfix is always the same:\n\n```\n/metadata.tsv\n```\n\nExample of download link for metadata.tsv with the filter explained before:\n\n```\nhttps://www.encodeproject.org/metadata/type=Experiment&limit=2&files.file_type=bed+narrowPeak/metadata.tsv\n```\n\nC.4. Tabular report\nTabular report is a customizable table, the table columns can be specified using any type of metadata related to the experiment, by accessing ENCODE Rest API it can select any metadata to be displayed.\n\nTo download the report.tsv, the creation of a URL is needed. The creation includes 2 blocks: prefix and filter.\n\nThe prefix is constant:\n\nhttps://www.encodeproject.org/report.tsv?\n\nThe filter is created as defined previously, an example that gets the metadata of files related to experiment, where files are bed narrowpeak:\n\ntype=Experiment&limit=2&files.file_type=bed+narrowPeak\n\nExample of download link for report.tsv with the filter explained before:\n\nhttps://www.encodeproject.org/report.tsv?type=Experiment&files.file_type=bed+narrowPeak\n\nC.5. Rest API\n\nENCODE provides web services for getting the metadata or any information obtained in their website into JSON format, therefore the complete tree structure for each experiment can be downloaded. Full description for Rest API procedure is explained in appendix I “ENCODE metadata generation for experiment JSON”.\n\nC.6. Metadata Filtering and Renaming\n\nAs not all the metadata inside the provided JSON is related to the files, filtering is needed, an example of pruned branch is the “files” node, that contains all the files referred by the experiment but only one is needed, the one corresponding to the region data file. Another example of the filtering needed is the “replicates” array in the experiment node, it contains\nall the biological replicates used in the experiment, but every file contains the references to the biological replicates used by the file, so the non-referenced have to be filtered out in order to have just metadata related to the file needed. Repeated metadata has also to be cleaned as original laboratory information is repeated in many entities while exploring the metadata tree. Finally when the metadata is clean and only the needed metadata is there, the naming of this metadata is done given the full extension of the path to follow from the root node, as an example:\n\n```\nExperiment__replicates__biosample__donor__organism__name = “human”\n```\n\nThis means the name of the organism of the donor used in the biological sample of the biological replicate of the file is human. Renaming of the useful metadata has to be done to be able to keep cleaning the metadata and to give to the user a more meaningful and standardized name to potentially every metadata field.\nAppendix D. XSD schema for GMQL Importer configuration file\n\n```xml\n<?xml version=\"1.0\"?>\n<xs:schema xmlns:xs=\"http://www.w3.org/2001/XMLSchema\"\n targetNamespace=\"http://polimi.it/GDMImporter\"\n xmlns=\"http://polimi.it/GDMImporter\"\n elementFormDefault=\"qualified\">\n <xs:element name=\"root\" type=\"root_type\">\n <xs:annotation>\n <xs:documentation>Literally the root of the xml document.</xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:complexType name=\"settings_type\">\n <xs:annotation>\n <xs:documentation>Contains the general settings for the application.</xs:documentation>\n </xs:annotation>\n <xs:sequence>\n <xs:element type=\"xs:string\" name=\"base_working_directory\">\n <xs:annotation>\n <xs:documentation>Root working directory for the application.</xs:documentation>\n <xs:documentation>Paths inside the configuration xml are relative to this path.</xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:element type=\"xs:boolean\" name=\"download_enabled\">\n <xs:annotation>\n <xs:documentation>Top level filter for allowing the application to download.</xs:documentation>\n <xs:documentation>If false, no source will be downloaded.</xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:element type=\"xs:boolean\" name=\"transform_enabled\">\n <xs:annotation>\n <xs:documentation>Top level filter for allowing the application to transform.</xs:documentation>\n <xs:documentation>If false, no source will be transformed.</xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:element type=\"xs:boolean\" name=\"load_enabled\">\n <xs:annotation>\n <xs:documentation>Top level filter for allowing the application to load.</xs:documentation>\n <xs:documentation>If false, no source will be loaded.</xs:documentation>\n </xs:annotation>\n </xs:element>\n </xs:sequence>\n </xs:complexType>\n</xs:schema>\n```\n<xs:element type=\"xs:boolean\" name=\"parallel_execution\">\n <xs:annotation>\n <xs:documentation>decides whether the application runs with multiple threads or not.</xs:documentation>\n <xs:documentation>If false, no parallel execution is enabled.</xs:documentation>\n </xs:annotation>\n</xs:element>\n\n<xs:complexType name=\"parameter_type\">\n <xs:annotation>\n <xs:documentation>Generic parameter with description, key name and value.</xs:documentation>\n </xs:annotation>\n <xs:sequence>\n <xs:element type=\"xs:string\" name=\"description\" minOccurs=\"0\">\n <xs:annotation>\n <xs:documentation>Explanation of what means the parameter in the application.</xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:element type=\"xs:string\" name=\"type\" minOccurs=\"0\">\n <xs:annotation>\n <xs:documentation>type for parameter, when multiple values to use in a single parameter.</xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:element type=\"xs:string\" name=\"key\">\n <xs:annotation>\n <xs:documentation>Name of the parameter.</xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:element type=\"xs:string\" name=\"value\">\n <xs:annotation>\n <xs:documentation>value of the parameter.</xs:documentation>\n </xs:annotation>\n </xs:element>\n </xs:sequence>\n</xs:complexType>\n\n<xs:complexType name=\"parameter_list_type\">\n <xs:annotation>\n <xs:documentation>List of parameters for source/dataset.</xs:documentation>\n </xs:annotation>\n <xs:sequence>\n <xs:element type=\"parameter_type\" name=\"parameter\" maxOccurs=\"unbounded\" minOccurs=\"0\"/>\n </xs:sequence>\n</xs:complexType>\n\n<xs:simpleType name=\"schema_location_type\" final=\"restriction\">\n <xs:annotation>\n <xs:documentation>Enumeration of possible locations for the schema files.</xs:documentation>\n </xs:annotation>\n</xs:simpleType>\n<xs:schema name=\"GMQLImporter\">\n\n <xs:annotation>\n <xs:documentation>\n XSD schema for GMQLImporter configuration file\n </xs:documentation>\n </xs:annotation>\n\n <xs:complexType name=\"schema_type\">\n <xs:simpleContent>\n <xs:extension base=\"xs:string\">\n <xs:attribute type=\"schema_location_type\" name=\"location\" use=\"required\">\n <xs:annotation>\n <xs:documentation>\n Schema file is inside the root working directory.\n </xs:documentation>\n </xs:annotation>\n </xs:attribute>\n <xs:enumeration value=\"local\">\n <xs:annotation>\n <xs:documentation>\n Schema file is inside the root working directory.\n </xs:documentation>\n </xs:annotation>\n </xs:enumeration>\n <xs:enumeration value=\"http\">\n <xs:annotation>\n <xs:documentation>\n Access through http.\n </xs:documentation>\n </xs:annotation>\n </xs:enumeration>\n </xs:extension>\n </xs:simpleContent>\n </xs:complexType>\n\n <xs:complexType name=\"dataset_type\">\n <xs:sequence>\n <xs:element type=\"xs:string\" name=\"dataset_working_directory\">\n <xs:annotation>\n <xs:documentation>\n Working directory for the dataset, subfolder of its source's working directory.\n </xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:element type=\"schema_type\" name=\"schema_url\">\n <xs:annotation>\n <xs:documentation>\n URL of the schema file.\n </xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:element type=\"xs:boolean\" name=\"download_enabled\">\n <xs:annotation>\n <xs:documentation>\n Indicates whether the dataset has to be downloaded.\n </xs:documentation>\n </xs:annotation>\n </xs:element>\n <xs:element type=\"xs:boolean\" name=\"transform_enabled\">\n <xs:annotation>\n <xs:documentation>\n Indicates whether the dataset has to be transformed.\n </xs:documentation>\n </xs:annotation>\n </xs:element>\n </xs:sequence>\n </xs:complexType>\n\n</xs:schema>\n<xs:documentation>Indicates whether the dataset has to be transformed.</xs:documentation>\n</xs:element>\n<xs:element type=\"xs:boolean\" name=\"load_enabled\">\n<xs:annotation>\n<xs:documentation>Indicates whether the dataset has to be loaded.</xs:documentation>\n</xs:annotation>\n</xs:element>\n<xs:element type=\"parameter_list_type\" name=\"parameter_list\">\n<xs:annotation>\n<xs:documentation>List of parameters for the dataset.</xs:documentation>\n</xs:annotation>\n</xs:element>\n<xs:sequence>\n<xs:attribute type=\"xs:string\" name=\"name\" use=\"required\">\n<xs:annotation>\n<xs:documentation>Name of the dataset, final name will be \"source-Name\"_\"datasetName\".</xs:documentation>\n</xs:annotation>\n</xs:attribute>\n<xs:complexType name=\"dataset_list_type\">\n<xs:annotation>\n<xs:documentation>List of datasets inside a source.</xs:documentation>\n</xs:annotation>\n<xs:sequence>\n<xs:element type=\"dataset_type\" name=\"dataset\" maxOccurs=\"unbounded\" minOccurs=\"0\"/>\n</xs:sequence>\n</xs:complexType>\n<xs:complexType name=\"source_type\">\n<xs:annotation>\n<xs:documentation>Represents a source, it has internal settings and contains a list of datasets.</xs:documentation>\n</xs:annotation>\n<xs:sequence>\n<xs:element type=\"xs:string\" name=\"url\">\n<xs:annotation>\n<xs:documentation>URL address for the source.</xs:documentation>\n</xs:annotation>\n</xs:element>\n<xs:element type=\"xs:string\" name=\"source_working_directory\">\n<xs:annotation>\n<xs:documentation>Working directory of the source, subfolder of root working directory</xs:documentation>\n</xs:element>\n</xs:sequence>\n</xs:complexType>\n<xs:element type=\"xs:string\" name=\"download_enabled\">\n <xs:annotation>\n <xs:documentation>Indicates whether the source is enabled to be downloaded, rules over dataset and is ruled by root settings.</xs:documentation>\n </xs:annotation>\n</xs:element>\n\n<xs:element type=\"xs:boolean\" name=\"transform_enabled\">\n <xs:annotation>\n <xs:documentation>Indicates whether the source is enabled to be transformed, rules over dataset and is ruled by root settings.</xs:documentation>\n </xs:annotation>\n</xs:element>\n\n<xs:element type=\"xs:boolean\" name=\"load_enabled\">\n <xs:annotation>\n <xs:documentation>Indicates whether the source is enabled to be loaded, rules over dataset and is ruled by root settings.</xs:documentation>\n </xs:annotation>\n</xs:element>\n\n<xs:element type=\"parameter_list_type\" name=\"parameter_list\">\n <xs:annotation>\n <xs:documentation>List of parameters needed for the source.</xs:documentation>\n </xs:annotation>\n</xs:element>\n\n<xs:element type=\"dataset_list_type\" name=\"dataset_list\">\n <xs:annotation>\n <xs:documentation>List of datasets contained by the source.</xs:documentation>\n </xs:annotation>\n</xs:element>\n<xs:annotation>\n <xs:element>\n <xs:complexType name=\"source_list_type\">\n <xs:annotation>\n <xs:documentation>List of sources to be handled in the configuration file.</xs:documentation>\n </xs:annotation>\n <xs:sequence>\n <xs:element type=\"source_type\" name=\"source\" maxOccurs=\"unbounded\" minOccurs=\"0\"/>\n </xs:sequence>\n </xs:complexType>\n </xs:element>\n</xs:annotation>\n\n<xs:complexType name=\"root_type\">\n <xs:annotation>\n <xs:documentation>Root node contains general settings and list of sources.</xs:documentation>\n </xs:annotation>\n <xs:sequence>\n <xs:element type=\"settings_type\" name=\"settings\"/>\n <xs:element type=\"source_list_type\" name=\"source_list\"/>\n </xs:sequence>\n</xs:complexType>\n</xs:schema>\nAppendix E. Database design for GMQLImporter\n\nA really important requirement for the solution is to maintain the genomic repository updated and provide historical status for every file and to know when there are new files or ones that are obsolete. A database was chosen to accomplish this task and in this appendix its model is explained. The database for GMQLImporter allows knowing the status for every file, on every dataset, on every source ever imported through GMQLImporter. Is possible to know whether a source was downloaded or transformed, also it’s belonging datasets and all the files inside the dataset.\n\nE.1. Sources, datasets and files\n\nTo know exactly the status and which files were provided by the source in a given execution, a general structure for sources, datasets and files is contained inside the GMQLImporter’s database, the possibilities to know how many files are provided on the source, how many were downloaded, transformed or loaded already. The history for every file, to know when they were updated is also contained. With this implementation, is possible to know the status of the files inside the repository at any given point in time, with the correspondent details of the files at that time. GMQLImporter can give important feedback for every execution so the user can know easily the status of the repository.\n\nE.2. Statistics\n\nDuring the execution of GMQLImporter some important information is collected, such as the number of available files for download from the source, the amount of failed or replaced files, the correctly transformed ones and the also the wrong ones. In every run the total\nnumber of files available to download or transformed is stored, together with the number of correct and failed ones, the number of files that do not fit the dataset’s schema and the time spent in some important tasks. GMQLImporter can provide this statistical historical data as it keeps track of them in the database.\n\nE.3. Configuration\n\nOn every run, the configuration XML file could differ and give a different output or substantial change to the status of the repository, therefore the information provided in the configuration file is stored for every run to know what the desired actions to perform in GMQLImporter were. As the configuration XML schema, is needed to store the general settings information, the specifications for every source involved and their datasets. The XML modifications are also noticed in the sources and datasets, as their names are the only valid identifier, therefore if a name is changed, it will be considered as another source or dataset. This is used in the development of this thesis by referring to ENCODE as 2 different sources, one that provides HG19 as reference genome for the data and the other that provides GRCh38 as reference.\n\nE.4. Database model\n\nHere the features of the database are explained, its indices and methods. In the following diagram all the database tables are shown, the primary keys are marked with PK, foreign keys are marked with FK, and unique valid restrictions are marked with U and a number to know which attributes are linked together. Most of the IDs use surrogate keys instead of natural keys to avoid the strings comparison when handling data inside the database and natural keys are kept indexed.\nIn this model, the sources with their datasets and files are represented by the tables Sources, Datasets and Files; the configurations for the execution are saved in tables Runs, RunSourceParameters and RunDatasetParameters where the configuration XML file parameters are saved distributed in the same way the XSD schema defines. Statistics are carried out using tables of RunFiles and RunDatasetLog where information is stored during runtime to let the user know the total available files to download and also failed, outdated and updated files during the execution.\nTo know the status of any file, 4 statuses are defined for a file:\n\n- **Updated**: The file download/transformation is correctly performed in the local repository as it was in the server the last time the dataset where the file belongs was downloaded. This means the file is ready to be used in the next step of transformation or loading.\n\n- **Failed**: The file download/transformation failed and the file may not be valid, in this case the file is marked as failed. This means the file is not usable for transforming or loading.\n\n- **Outdated**: The file was removed from the server; this causes the file to exist locally but not remotely. This means the file is not included in the next transformation or loading step.\n\n- **Compare**: Auxiliary status used to know which files do not exist anymore on the server, this status is meant to be used while the program is executing. No files are kept in this state after the program execution.\n\nThe following diagram shows the transitions of different file statuses and after every function inside is explained.\nThe main database methods include:\n\n- **markToCompare**: by receiving a dataset, the database changes the status of every file in the dataset as to compare, this method is used to notice which files are no longer in the server side and have to be marked after as outdated in the local copy.\n\n- **markAsUpdated**: indicates the file was correctly downloaded or transformed and that is ready for the next step that could be transformation or loading.\n\n- **markAsFailed**: when trying to download or transform a file, if the procedure fails, the file has to be excluded from further processing and thus is marked as failed.\n\n- **markAsOutdated**: once the whole dataset is downloaded or transformed this procedure allows finding the files that no longer exist in the server, and marks those files as outdated. These files are no longer used in transformation or loading procedure.\n\n- **getFileNameAndCopyNumber**: as a source could have more than one file with the same name but in different folders, at the moment to put them together in the local folder this could be a problem. The database handles this when 2 or more files arrive with potentially the same name and renames them in FIFO order, adding the copy number at the end of the file name.\n\n- **checkIfUpdateFile**: by receiving a file’s remote data such as hash, file size or last modification date, the database checks its records to know if the file has or not to be downloaded.\n\nThe database also is configured to insert data if it does not exist or to retrieve it if it exists, as an example, when trying to create a source, it will check if the source already exists and if it exists it will access to the source already stored, on the other hand if the source does not exist, it will be created and then accessed.\nAppendix F. GMQLImporter console & file logging\n\nF.1. Introduction\n\nGMQL-Importer provides feedback to the user both by console and file logging every time it is executed; every execution of the program is called run. This log allows the user to know the updated running status of GMQLImporter and also to search most of the operations done in the run. Also at the end of each run, it shows general statistics for the run among the different sources and datasets.\n\nF.2. SLF4J + log4j\n\nSimple Logging Facade for Java (SLF4J) is a Java logging API that serves as abstraction for multiple logging frameworks, such as the one used in GMQLImporter, log4j. This logger is set up at runtime and allows the communication in the console, and also straight to a file. The logging framework provides a level oriented messaging with the following levels (in decreasing priority order) ERROR, WARN, INFO, DEBUG or TRACE; ERROR is meant to communicate wrong functioning of the process, WARN is used to notice the user that something is not completely correct but the program can still work, INFO is to communicate general message feedback to the user in the application, DEBUG is used to describe the internal steps taken in the program for developers to have extra information during the program run, and TRACE is to fine grain the debugging by communicating more details to developers. The logger has the option to set up a threshold level, this allows to limit information shown to the user and to easily create multiple types of log, such as in GMQLImporter where log4j is used to show just up to INFO to the user, and DEBUG for developers.\n\nF.3. Messages\nMessages are labeled with their level (ERROR, WARN, INFO, DEBUG or TRACE), represented in a tree structure ordered by time of appearance (all possible options are shown, not all of them are mandatory) here just an explanation of what is shown in the console is given, not the exact given message in the log. The file log is set with the threshold DEBUG and the console log with INFO.\n\nF.4. Main Program:\n\n- [INFO] Help menu is printed if it is asked in the program arguments.\n- [INFO] Path for the GMQL configuration xml file and configuration folder given in the arguments.\n- [INFO] If database had to be created.\n- [WARN] If no configuration folder for GMQL or no run specified when asked information for a run (see appendix J “Console manual for GMQLImporter”).\n- [INFO] The configuration xml file is valid for the GMQL-Importer schema.\n- [WARN] If the configuration xml file is not valid or the user cancels the run.\n- [WARN] If the given metadata replacement names are repeated (see appendix K “Metadata replacement for ENCODE in GMQLImporter”)\n- [INFO] Notifies when a source starts to download, transform or load.\n- Download log (in section 6.3.1).\n- Transform log (in section 6.3.2).\n- Load log (in section 6.3.3).\n- [INFO] General statistics at the end of the run, showing for each source and dataset the available files to download or transform and the correctly downloaded or transformed ones and the time taken in the processes.\n\nF.5. Download:\n\nF.6. FTP download\n\n- [INFO] Connection established or retrying to connect.\n- [WARN] Connection lost.\n- [DEBUG] If any folder is created (usually when is the first run where no local folders exist)\n- [ERROR] Could not connect to the FTP server.\n- For each folder being scanned in the source:\n - [INFO] Folder’s name.\n - [INFO] If the folder’s name matches the regular expressions, tells is searching inside.\n - [WARN] If the folder couldn’t be created.\n - [INFO] If it is trying to retry download of failed files.\n- For each file being downloaded:\n - [INFO] Current folder and file being downloaded and if the hash code matches.\n - [INFO] Current status of the file in the database, UPDATED, OUTDATED, FAILED.\n- [WARN] If the file download failed 3 times consecutively.\n\n- [WARN] if the internet connection was lost or couldn’t access to the directory.\n - [INFO] Summary of how many total files were available from the source’s folder and how many were successfully downloaded.\n - [INFO] Downloading time for the folder\n\n- [INFO] Source download finished.\n\n- [INFO] Downloading time for the source\n\n### F.7. ENCODE download\n\n- [DEBUG] If any folder is created (usually when is the first run where no local folders exist)\n\n- For each dataset to be downloaded:\n - [INFO] Name of the dataset being downloaded.\n - [WARN] If any problem with metadata.tsv file.\n - For each file to be downloaded:\n - [INFO] Download started or finished, indicating whether it is for JSON file or region data.\n - [WARN] Connection issues or problems downloading files.\n - Dataset summary of available files to download and successfully downloaded ones.\n• [INFO] Source download finished.\n\nF.8. Transformation:\n\n• [INFO] Starting transformation for the source.\n\n• For each dataset in the source:\n \n o [INFO] Starting transformation for dataset.\n\n o [INFO] If the schema file was downloaded.\n\n o [WARN] If the schema file is not found.\n\n o [DEBUG] If any folder is created (usually when is the first run).\n\n o For each file to process:\n\n ▪ [INFO] Transformation process started\n\n ▪ TCGA2BED transformation (NULLTransformer):\n\n ▪ [INFO] File copied, showing origin and destination paths.\n\n ▪ [WARN] If the file failed to copy.\n\n ▪ ENCODE transformation (ENCODETransformer):\n\n ▪ [INFO] If the file is region data and Gzipped, start unGzipping, and when finished.\n\n ▪ [INFO] Start and finish times of metadata transformation.\n\n ▪ [INFO] If the metadata is extracted from JSON file or metadata.tsv.\n\n ▪ [WARN] If the files cannot be extracted or written.\n• [WARN] If any file does not respect the schema or could not be transformed.\n\n• [DEBUG] If any metadata key is modified, e.g. for normalization of separation characters, validation for java identifier.\n\n o Summary of modified files inside the current dataset, printing files that do not respect the schema, or if the region data or metadata were changed and transformation time for dataset.\n\n• [INFO] Summary of modified files in the process of the source transformation, showing files that do not respect the schema, or if any region data or metadata was changed.\n\n• [INFO] Transformation for the source finished.\n\n• [INFO] Transformation time for the source.\n\nF.9. Load:\n\n• [INFO] Preparing to load the source into GMQL.\n\n• [INFO] Each dataset to be loaded and the user to be loaded to.\n\n• [WARN] If any region data or metadata file is missing.\n\n• [INFO] Each dataset that finished loading the files.\n\n• [INFO] If the dataset has no files, notify that dataset.\n\n• [INFO] Loading time, overall and for every dataset\nAppendix G. Creation of XML configuration file for GMQLImporter\n\nThis document follows the XML schema explained in chapter 5 using the XSD schema exposed in appendix D “XSD schema for GMQLImporter”, complementing it with 2 sources to be imported into GMQLRepository, the first TCGA2BED (explained in appendix “TCGA2BED datasets organization”) and finally ENCODE (structure defined in appendix C “ENCODE Metadata Explanation for GDM” and appendix I “ENCODE metadata generation for experiment JSON”)\n\nG.1. Root node\n\nThe root node contains the namespace for the xsd file to be used in the configuration XML, general settings for the program to run such as:\n\n- **base_working_directory**: “/home/nacho/GMQL-Importer/workingDirectory” indicates the location path for the folder to be used in downloading and transforming the later specified sources.\n\n- **download_enabled**: “true” sets the program to run downloads, this is a top level selection for download, if this is false: neither source nor dataset are going to be downloaded.\n\n- **transform_enabled**: “true” sets the program to run transformation of downloaded datasets, this top level selection enables transformation for sources and datasets if their transform_enabled attribute is also true.\n\n- **load_enabled**: “false” sets the program not to load the transformed data into GMQL repository. This top level selection blocks any source or dataset to be loaded into GMQL repository.\n• parallel_execution: “true” sets the program to run in parallel when allowed inside the code, when false it will run sequentially.\n\nG.2. Source list node\n\nThe source list contains the candidate sources to be downloaded, transformed and loaded into GMQLRepository with their basic details to get and process the datasets they provide. The sources included in the attached XML configuration file are:\n\nG.3. HG19_TCGA\n\nRepresents the TCGA2BED source for downloading files, these files use HG19 as reference genome, its details are the following\n\n• url: “bioinf.iasi.cnr.it” this is the base URL for connecting to the ftp server of TCGA2BED.\n\n• source_working_directory: “HG19_TCGA” this is the local folder to be used to store all downloaded and transformed data from TCGA2BED source, this folder will be inside the base_working_directory defined in the settings in the root node.\n\n• downloader: “it.polimi.genomics.importer.DefaultImporter.FTPDownloader” as the download for TCGA2BED is done by traversing an ftp directory recursively and matching by regular expressions, FTPDownloader is selected to perform the download process.\n\n• transformer: “it.polimi.genomics.importer.DefaultImporter.NULLTransformer” for transformation of TCGA2BED data is needed just to copy the downloaded files, therefore NULLTransformer is needed for transformation.\n\n• loader: “it.polimi.genomics.importer.GMQLImporter.GMQLLoader” as the datasets are meant to be loaded into GMQL repository, GMQLLoader is needed to achieve this.\n• download_enabled: “true” if root download_enabled is true, this source is going to be downloaded.\n\n• transform_enabled: “true” if root transform_enabled is true, this source is going to be transformed.\n\n• load_enabled: “true” if root load_enabled is true, this source is going to be loaded into GMQL.\n\n• parameter_list: here specific parameters for TCGA2BED are listed\n o metadataReplacement: “XML/metadataReplacementTcga.XML” used to change the “|” character for metadata separator for “__”.\n o gmql_user: “public” indicates which GMQL user are the files going to be added when load.\n o username: “anonymous” in the TCGA2BED FTP server the configuration is done with an anonymous user and no password.\n o password: this field is empty as no password is required.\n\n• dataset_list for this source is explained in section 3.1.\n\nG.4. HG19_ENCODE\n\nRepresents the ENCODE source for downloading files, in experiments using HG19 as reference genome, its details are:\n\n• URL: “https://www.encodeproject.org/” this is the base URL for accessing ENCODE files.\n\n• source_working_directory: “HG19_ENCODE” this is the local folder to be used to store all downloaded and transformed data from ENCODE source, this folder will be inside the base_working_directory defined in the settings in the root node.\n• downloader: “it.polimi.genomics.importer.ENCODEImporter.ENCODEDownloader” as the download for ENCODE is done by specific batch download, an specific downloader is needed to get the files.\n\n• transformer: “it.polimi.genomics.importer.ENCODEImporter.ENCODETransformer” for transformation of ENCODE a specific procedure is needed as explained in appendix C “ENCODE Metadata Explanation for GDM”.\n\n• loader: “it.polimi.genomics.importer.GMQLImporter.GMQLLoader” as the datasets are meant to be loaded into GMQL repository, GMQLLoader is needed to achieve this.\n\n• download_enabled: “true” if root download_enabled is true, this source is going to be downloaded.\n\n• transform_enabled: “true” if root transform_enabled is true, this source is going to be transformed.\n\n• load_enabled: “true” if root load_enabled is true, this source is going to be loaded into GMQL.\n\n o parameter_list: specific parameters for ENCODE source are the following\n\n o gmql_user: “public” indicates which GMQL user are the files going to be added when load.\n\n o metadata_prefix: “metadata/” for generation of batch download URL is needed this prefix to obtain the metadata.tsv file.\n\n o metadata_suffix: “/metadata.tsv” for generation of batch download URL is needed this suffix to obtain the metadata.tsv file.\nCreation of XML configuration file for GMQLImporter\n\n- json_prefix: “experiments/” for JSON download from ENCODE is needed this prefix, as explained in “ENCODE metadata generation for experiment JSON”, the metadata root file is the experiment entity.\n\n- json_suffix: “/?frame=embedded&format=json/” for JSON download embedded frame is used and format is JSON.\n\n- metadata_name_separation_char: “__” specifies the double underscore as separator for metadata.\n\n- encode_metadata_exclusion: “^contributing_files.*$” this category is excluded as it was found as not useful metadata.\n\n- encode_metadata_exclusion: “^original_files.*$” this category is excluded as it was found as not useful metadata.\n\n- encode_metadata_exclusion: “^.*analysis_step_version.*$” this category is excluded as it was found as not useful metadata.\n\n- encode_metadata_exclusion: “^.*derived_from.*$” this category is excluded as it was found as not useful metadata.\n\n- encode_metadata_exclusion: “^.*revoked_files.*$” this category is excluded as it was found as not useful metadata.\n\n- encode_metadata_exclusion: “^assembly$” this category is excluded as it was found as not useful metadata.\n\n- metadata_replacement: “XML/metadataReplacement.XML” reference to an XML file containing the replacements for metadata names.\n\n- metadata_extraction: “tsv” for Encode, json or tsv extraction method for metadata can be specified.\nCreation of XML configuration file for GMQLImporter\n\n- assembly_exclude: “GRCh38” as some files with GRCh38 reference genome are passed by Encode, this parameter is used to filter them out.\n\n- dataset_list for this source is explained in section 3.2.\n\nG.5. GRCh38_ENCODE\n\nRepresents the ENCODE source for downloading files, in experiments using GRCh38 as reference genome, its details are:\n\n- url: “https://www.encodeproject.org/” this is the base URL for accessing ENCODE files.\n\n- source_working_directory: “GRCh38_ENCODE” this is the local folder to be used to store all downloaded and transformed data from ENCODE source, this folder will be inside the base_working_directory defined in the settings in the root node.\n\n- downloader: “it.polimi.genomics.importer.ENCODEImporter.ENCODEDownloader” as the download for ENCODE is done by specific batch download, a specific downloader is needed to get the files.\n\n- transformer: “it.polimi.genomics.importer.ENCODEImporter.ENCODETransformer” for transformation of ENCODE an specific procedure is needed as explained in “ENCODE Metadata Explanation for GDM”.\n\n- loader: “it.polimi.genomics.importer.GMQLImporter.GMQLLoader” as the datasets are meant to be loaded into GMQL repository, GMQLLoader is needed to achieve this.\n\n- download_enabled: “true” if root download_enabled is true, this source is going to be downloaded.\n\n- transform_enabled: “true” if root transform_enabled is true, this source is going to be transformed.\n• load_enabled: “true” if root load_enabled is true, this source is going to be loaded into GMQL.\n\n• parameter_list: specific parameters for ENCODE source are the following\n o gmql_user: “public” indicates which GMQL user are the files going to be added when load.\n o metadata_prefix: “metadata/” for generation of batch download URL is needed this prefix to obtain the metadata.tsv file.\n o metadata_suffix: “/metadata.tsv” for generation of batch download URL is needed this suffix to obtain the metadata.tsv file.\n o json_prefix: “experiments/” for JSON download from ENCODE is needed this prefix, as explained in appendix I “ENCODE metadata generation for experiment JSON”, the metadata root file is the experiment entity.\n o json_suffix: “/?frame=embedded&format=json/” for JSON download embedded frame is used and format is JSON.\n o metadata_name_separation_char: “__” specifies the double underscore as separator for metadata.\n o encode_metadata_exclusion: “^contributing_files.*$” this category is excluded as it was found as not useful metadata.\n o encode_metadata_exclusion: “^original_files.*$” this category is excluded as it was found as not useful metadata.\n o encode_metadata_exclusion: “^.*analysis_step_version.*$” this category is excluded as it was found as not useful metadata.\n o encode_metadata_exclusion: “^.*derived_from.*$” this category is excluded as it was found as not useful metadata.\no encode_metadata_exclusion: \"^.*revoked_files.*$\" this category is excluded as it was found as not useful metadata.\n\no encode_metadata_exclusion: \"^assembly$\" this category is excluded as it was found as not useful metadata.\n\no metadata_replacement: \"XML/metadataReplacement.XML\" references to an XML file containing the replacements for metadata names.\n\no metadata_extraction: \"tsv\" for ENCODE, json or tsv extraction method for metadata can be specified.\n\no assembly_exclude: \"hg19\" as some files with hg19 reference genome are passed by ENCODE, this parameter is used to filter them out.\n\n- dataset_list for this source is explained in section 3.3.\n\nG.6. Datasets by source\n\nG.7. HG19_TCGA datasets\n\nTCGA2BED dataset generation is explained in “Preparation of configuration.XML file for downloading TCGA2BED datasets” its implementation is the following:\n\nG.8. cnv\n\nContains cnv experiments in GDM format for region data and metadata.\n\n- dataset_working_directory: “cnv” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- schema_url: “location=http” means the schema file has to be downloaded with http method, “ftp://bioinf.lasi.cnr.it/bed/acc/cnv/header.schema” indicates the full URL to download the schema file.\nCreation of XML configuration file for GMQLImporter\n\n- download_enabled: “true” lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n- transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- parameter_list: specific parameters for cnv dataset\n - folder_regex: “^/bed/.*/cnv” is the regular expression to access all cnv folders in TCGA2BED FTP server.\n - files_regex: “.*\\.(\\bed|\\bed\\.(\\meta)?)$” regular expression to download .bed and .bed.meta from every cnv folder.\n - md5_checksum_tcga2bed: “md5table.txt” this file on each cnv folder has details for md5 hash of all files in the folder.\n - exp_info_tcga2bed: “exp_info.tsv” this file contains the number of files inside cnv folder to download.\n\nG.9. dnamethylation\n\nContains dnamethylation (27 and 450) experiments in GDM format for region data and metadata.\n\n- dataset_working_directory: “dnamethylation” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n• schema_url: “location=http” means the schema file has to be downloaded with http method, “ftp://bioinf.iasi.cnr.it/bed/lusc/dnamethylation27/header.schema” indicates the full URL to download the schema file.\n\n• download_enabled: “true” lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n• transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n• load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n• parameter_list: specific parameters for dnamethylation dataset\n o folder_regex: “^/bed/.*/dnamethylation.*” is the regular expression to access all dnamethylation folders in TCGA2BED FTP server.\n o files_regex: “.*\\bed\\(\\meta\\)?$” regular expression to download .bed and .bed.meta from every dnamethylation folder.\n o md5_checksum_tcga2bed: “md5table.txt” this file on each dnamethylation folder has details for md5 hash of all files in the folder.\n o exp_info_tcga2bed: “exp_info.tsv” this file contains the number of files inside dnamethylation folder to download.\n\nG.10. dnaseq\n\nContains dnaseq experiments in GDM format for region data and metadata.\n\n• dataset_working_directory: “dnaseq” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\nCreation of XML configuration file for GMQLImporter\n\n- **schema_url:** \"location=http\" means the schema file has to be downloaded with http method, “ftp://bioinf.iiasi.cnr.it/bed/lusc/dnaseq/header.schema” indicates the full URL to download the schema file.\n\n- **download_enabled:** “true” lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n- **transform_enabled:** “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- **load_enabled:** “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- **parameter_list:** specific parameters for dnaseq dataset\n - **folder_regex:** \"^/bed/.*/dnaseq\" is the regular expression to access all dnaseq folders in TCGA2BED FTP server.\n - **files_regex:** \".*\\.bed\\(\\|\\.meta\\)?$\" regular expression to download .bed and .bed.meta from every dnaseq folder.\n - **md5_checksum_tcga2bed:** “md5table.txt” this file on each dnaseq folder has details for md5 hash of all files in the folder.\n - **exp_info_tcga2bed:** “exp_info.tsv” this file contains the number of files inside dnaseq folder to download.\n\n**G.11. mirnaseq_isoform**\n\nContains mirnaseq_isoform experiments in GDM format for region data and metadata.\n\n- **dataset_working_directory:** “mirnaseq_isoform” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\nCreation of XML configuration file for GMQLImporter\n\n- schema_url: “location=http” means the schema file has to be downloaded with http method,\n “ftp://bioinf.iasi.cnr.it/bed/lusc/mirnaseq/isoform.quantification/header.schema” indicates the full URL to download the schema file.\n\n- download_enabled: “true” lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n- transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- parameter_list: specific parameters for mirnaseq_isoform dataset\n - folder_regex: “^/bed/.*mirnaseq/isoform.quantification” is the regular expression to access all mirnaseq_isoform folders in TCGA2BED FTP server.\n - files_regex: “.*\\.bed\\.(\\.|meta)?$” regular expression to download .bed and .bed.meta from every mirnaseq_isoform folder.\n - md5_checksum_tcga2bed: “md5table.txt” this file on each mirnaseq_isoform folder has details for md5 hash of all files in the folder.\n - exp_info_tcga2bed: “exp_info.tsv” this file contains the number of files inside mirnaseq_isoform folder to download.\n\nG.12. mirnaseq_mirna\n\nContains mirnaseq_mirna experiments in GDM format for region data and metadata.\n• dataset_working_directory: “mirnaseq_mirna” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n• schema_url: “location=http” means the schema file has to be downloaded with http method, “ftp://bioinf.iasi.cnr.it/bed/lusc/mirnaseq/mirna.quantification/header.schema” indicates the full URL to download the schema file.\n\n• download_enabled: “true” lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n• transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n• load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n• parameter_list: specific parameters for mirnaseq_mirna dataset\n o folder_regex: “^/bed/.*/mirnaseq/mirna.quantification” is the regular expression to access all mirnaseq_mirna folders in TCGA2BED FTP server.\n\n o files_regex: “.*\\.(bed|\\.(meta))?$” regular expression to download .bed and .bed.meta from every mirnaseq_mirna folder.\n\n o md5_checksum_tcga2bed: “md5table.txt” this file on each mirnaseq_mirna folder has details for md5 hash of all files in the folder.\n\n o exp_info_tcga2bed: “exp_info.tsv” this file contains the number of files inside mirnaseq_mirna folder to download.\n\nG.13. rnaseq_exon\nContains rnaseq_exon experiments in GDM format for region data and metadata.\n\n- **dataset_working_directory**: “rnaseq_exon” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- **schema_url**: “location=http” means the schema file has to be downloaded with http method,\n “ftp://bioinf.iasi.cnr.it/bed/lusc/rnaseq/exon.quantification/header.schema” indicates the full URL to download the schema file.\n\n- **download_enabled**: “true” lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n- **transform_enabled**: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- **load_enabled**: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- **parameter_list**: specific parameters for rnaseq_exon dataset\n - folder_regex: “^/bed/.*\\/rnaseq/exon.quantification” is the regular expression to access all rnaseq_exon folders in TCGA2BED FTP server.\n - files_regex: “.*\\.bed\\(|\\.meta)?$” regular expression to download .bed and .bed.meta from every rnaseq_exon folder.\n - md5_checksum_tcga2bed: “md5table.txt” this file on each rnaseq_exon folder has details for md5 hash of all files in the folder.\n - exp_info_tcga2bed: “exp_info.tsv” this file contains the number of files inside rnaseq_exon folder to download.\nG.14. **rnaseq_gene**\n\nContains rnaseq_gene experiments in GDM format for region data and metadata.\n\n- **dataset_working_directory**: \"rnaseq_gene\" this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- **schema_url**: “location=http” means the schema file has to be downloaded with http method, “ftp://bioinf.iiasi.cnr.it/bed/lusc/rnaseq/gene.quantification/header.schema” indicates the full URL to download the schema file.\n\n- **download_enabled**: “true” lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n- **transform_enabled**: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- **load_enabled**: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- **parameter_list**: specific parameters for rnaseq_gene dataset\n - **folder_regex**: “^/bed/.*/rnaseq/gene.quantification” is the regular expression to access all rnaseq_gene folders in TCGA2BED FTP server.\n - **files_regex**: “.*\\.(bed\\.\\.(meta))?$” regular expression to download .bed and .bed.meta from every rnaseq_gene folder.\n - **md5_checksum_tcga2bed**: “md5table.txt” this file on each rnaseq_gene folder has details for md5 hash of all files in the folder.\no exp_info_tcga2bed: \"exp_info.tsv\" this file contains the number of files inside rnaseq_gene folder to download.\n\n**G.15. rnaseq_spljxn**\n\nContains rnaseq_spljxn experiments in GDM format for region data and metadata.\n\n- dataset_working_directory: \"rnaseq_spljxn\" this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- schema_url: \"location=http\" means the schema file has to be downloaded with http method, \"ftp://bioinf.iasi.cnr.it/bed/lusc/rnaseq/spljxn.quantification/header.schema\" indicates the full URL to download the schema file.\n\n- download_enabled: \"true\" lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n- transform_enabled: \"true\" lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- load_enabled: \"true\" lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- parameter_list: specific parameters for rnaseq_spljxn dataset\n - folder_regex: \"^/bed/.*rnaseq/spljxn.quantification\" is the regular expression to access all rnaseq_spljxn folders in TCGA2BED FTP server.\n - files_regex: \".*\\.(bed\\|.meta)?\" regular expression to download .bed and .bed.meta from every rnaseq_spljxn folder.\nCreation of XML configuration file for GMQIimporter\n\n- `md5_checksum_tcga2bed`: \"md5table.txt\" this file on each `rnaseq_spljxn` folder has details for md5 hash of all files in the folder.\n\n- `exp_info_tcga2bed`: \"exp_info.tsv\" this file contains the number of files inside `rnaseq_spljxn` folder to download.\n\nG.16. `rnaseqv2_exon`\n\nContains `rnaseqv2_exon` experiments in GDM format for region data and metadata.\n\n- `dataset_working_directory`: \"`rnaseqv2_exon\" this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- `schema_url`: \"location=http\" means the schema file has to be downloaded with http method, \"ftp://bioinf.iiasi.cnr.it/bed/lusc/rnaseqv2/exon.quantification/header.schema\" indicates the full URL to download the schema file.\n\n- `download_enabled`: \"true\" lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n- `transform_enabled`: \"true\" lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- `load_enabled`: \"true\" lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- `parameter_list`: specific parameters for `rnaseqv2_exon` dataset\n\n - `folder_regex`: \"^/bed/.*/rnaseqv2/exon.quantification\" is the regular expression to access all `rnaseqv2_exon` folders in TCGA2BED FTP server.\no files_regex: \".*\\.bed(\\.meta)?\" regular expression to download .bed and .bed.meta from every rnaseqv2_exon folder.\n\no md5_checksum_tcga2bed: “md5table.txt” this file on each rnaseqv2_exon folder has details for md5 hash of all files in the folder.\n\no exp_info_tcga2bed: “exp_info.tsv” this file contains the number of files inside rnaseqv2_exon folder to download.\n\nG.17. rnaseqv2_gene\n\nContains rnaseqv2_gene experiments in GDM format for region data and metadata.\n\n- dataset_working_directory: “rnaseqv2_gene” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- schema_url: “location=http” means the schema file has to be downloaded with http method, “ftp://bioinf.iasi.cnr.it/bed/lusc/rnaseqv2/gene.quantification/header.schema” indicates the full URL to download the schema file.\n\n- download_enabled: “true” lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n\n- transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- parameter_list: specific parameters for rnaseqv2_gene dataset\no folder_regex: “^/bed/.*/rnaseqv2/gene.quantification” is the regular expression to access all rnaseqv2_gene folders in TCGA2BED FTP server.\n\no files_regex: “.*\\.(bed|(\\.|meta))?$” regular expression to download .bed and .bed.meta from every rnaseqv2_gene folder.\n\no md5_checksum_tcga2bed: “md5table.txt” this file on each rnaseqv2_gene folder has details for md5 hash of all files in the folder.\n\no exp_info_tcga2bed: “exp_info.tsv” this file contains the number of files inside rnaseqv2_gene folder to download.\n\nG.18. rnaseqv2_isoform\n\nContains rnaseqv2_isoform experiments in GDM format for region data and metadata.\n\n- dataset_working_directory: “rnaseqv2_isoform” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- schema_url: “location=http” means the schema file has to be downloaded with http method, “ftp://bioinf.iasi.cnr.it/bed/lusc/rnaseqv2/isoform.quantification/header.schema” indicates the full URL to download the schema file.\n\n- download_enabled: “true” lowest level activator for download; it will only be downloaded if its source and root nodes are active.\n\n- transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\nCreation of XML configuration file for GMQLImporter\n\n- parameter_list: specific parameters for rnaseqv2_isoform dataset\n - folder_regex: “/bed/.*rnaseqv2/isoform.quantification” is the regular expression to access all rnaseqv2_isoform folders in TCGA2BED FTP server.\n - files_regex: “.*\\.bed(\\.meta)?$” regular expression to download .bed and .bed.meta from every rnaseqv2_isoform folder.\n - md5_checksum_tcga2bed: “md5table.txt” this file on each rnaseqv2_isoform folder has details for md5 hash of all files in the folder.\n - exp_info_tcga2bed: “exp_info.tsv” this file contains the number of files inside rnaseqv2_isoform folder to download.\n\nG.19. rnaseqv2_spljxn\n\nContains rnaseqv2_spljxn experiments in GDM format for region data and metadata.\n\n- dataset_working_directory: “rnaseqv2_spljxn” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- schema_url: “location=http” means the schema file has to be downloaded with http method, “ftp://bioinf.iasi.cnr.it/bed/lusc/rnaseqv2/spljxn.quantification/header.schema” indicates the full URL to download the schema file.\n\n- download_enabled: “true” lowest level activator for download; it will only be downloaded if its source and root nodes are active.\n\n- transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n• load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n• parameter_list: specific parameters for rnaseqv2_spljxn dataset\n o folder_regex: “^/bed/.*/rnaseqv2/spljxn.quantification” is the regular expression to access all rnaseqv2_spljxn folders in TCGA2BED FTP server.\n o files_regex: “.*\\.bed(\\.|meta)?$” regular expression to download .bed and .bed.meta from every rnaseqv2_spljxn folder.\n o md5_checksum_tcga2bed: “md5table.txt” this file on each rnaseqv2_spljxn folder has details for md5 hash of all files in the folder.\n o exp_info_tcga2bed: “exp_info.tsv” this file contains the number of files inside rnaseqv2_spljxn folder to download.\n\nG.20. HG19_ENCODE datasets\n\nDatasets for HG19_ENCODE include broadPeak and narrowPeak.\n\nG.21. broadPeak\n\nContains broadPeak data for HG19 reference genome stored in the ENCODE project\n\n• dataset_working_directory: “broadPeak” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n• schema_url: “location=local” means the schema file is stored in local media relative to root node base_working_directory; “schemas/broadPeak.schema” indicates the relative path for the broadPeak schema.\n\n• download_enabled: “true” lowest level activator for download, it will only be downloaded if its source and root nodes are active.\n• transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n• load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n• parameter_list: specific parameters for HG19_ENCODE broadPeak dataset\n\n o loading_name: “HG19_ENCODE_BROAD_MAY_2017” indicates the name that will be given to the dataset in the loading process. By default it joins source name and dataset name with an underscore between them.\n\n o type: “Experiment” used in the creation of the batch download URL, defines the experiment entity as the base to search for.\n\n o files.file_type: “bed+broadPeak” used in the creation of the batch download URL, filters experiments with bed broadPeak files.\n\n o award.project: “ENCODE” used in the creation of the batch download URL, defines only the files from project ENCODE to be downloaded.\n\n o files.assembly: “hg19” used in the creation of the batch download URL, defines only hg19 assembly files to be downloaded.\n\nG.22. narrowPeak\n\nContains narrowPeak data for HG19 reference genome stored in the ENCODE project\n\n• dataset_working_directory: “narrowPeak” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n• schema_url: “location=local” means the schema file is stored in local media relative to root node base_working_directory; “schemas/narrowPeak.schema” indicates the relative path for the broadPeak schema.\n\n• download_enabled: “true” lowest level activator for download; it will only be downloaded if its source and root nodes are active.\n\n• transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n• load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n• parameter_list: specific parameters for HG19_ENCODE narrowPeak dataset\n \n o loading_name: “HG19_ENCODE_NARROW_MAY_2017” indicates the name that will be given to the dataset in the loading process. By default it joins source name and dataset name with an underscore between them.\n\n o type: “Experiment” used in the creation of the batch download URL, defines the experiment entity as the base to search for.\n\n o files.file_type: “bed+narrowPeak” used in the creation of the batch download URL, filters experiments with bed narrowPeak files.\n\n o award.project: “ENCODE” used in the creation of the batch download URL, defines only the files from project ENCODE to be downloaded.\n\n o files.assembly: “hg19” used in the creation of the batch download URL, defines only hg19 assembly files to be downloaded.\n\nG.23. GRCh38_ENCODE datasets\n\nDatasets for GRCh38_ENCODE include broadPeak and narrowPeak.\nG.24. broadPeak\n\nContains broadPeak data for GRCh38 reference genome stored in the ENCODE project\n\n- dataset_working_directory: “broadPeak” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- schema_url: “location=local” means the schema file is stored in local media relative to root node base_working_directory; “schemas/broadPeak.schema” indicates the relative path for the broadPeak schema.\n\n- download_enabled: “true” lowest level activator for download; it will only be downloaded if its source and root nodes are active.\n\n- transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- parameter_list: specific parameters for GRCh38_ENCODE broadPeak dataset\n - loading_name: “GRCh38_ENCODE_BROAD_MAY_2017” indicates the name that will be given to the dataset in the loading process. By default it joins source name and dataset name with an underscore between them.\n - type: “Experiment” used in the creation of the batch download URL, defines the experiment entity as the base to search for.\n - files.file_type: “bed+broadPeak” used in the creation of the batch download URL, filters experiments with bed broadPeak files.\n - award.project: “ENCODE” used in the creation of the batch download URL, defines only the files from project ENCODE to be downloaded.\nfiles.assembly: “GRCh38” used in the creation of the batch download URL, defines only GRCh38 assembly files to be downloaded.\n\nG.25. narrowPeak\n\nContains narrowPeak data for GRCh38 reference genome stored in the ENCODE project\n\n- dataset_working_directory: “narrowPeak” this is the local folder to store downloaded and transformed files for the dataset, this folder will be under its source folder.\n\n- schema_url: “location=local” means the schema file is stored in local media relative to root node base_working_directory; “schemas/narrowPeak.schema” indicates the relative path for the broadPeak schema.\n\n- download_enabled: “true” lowest level activator for download; it will only be downloaded if its source and root nodes are active.\n\n- transform_enabled: “true” lowest level activator for transformation, it will only be transformed if its source and root nodes have transform_enabled set to true.\n\n- load_enabled: “true” lowest level activator for load, it will only be loaded if root and source nodes are active also.\n\n- parameter_list: specific parameters for GRCh38_ENCODE narrowPeak dataset\n - loading_name: “GRCh38_ENCODE_NARROW_MAY_2017” indicates the name that will be given to the dataset in the loading process. By default it joins source name and dataset name with an underscore between them.\n\n - type: “Experiment” used in the creation of the batch download URL, defines the experiment entity as the base to search for.\no files.file_type: “bed+narrowPeak” used in the creation of the batch download URL, filters experiments with bed narrowPeak files.\n\no award.project: “ENCODE” used in the creation of the batch download URL, defines only the files from project ENCODE to be downloaded.\n\no files.assembly: “GRCh38” used in the creation of the batch download URL, defines only GRCh38 assembly files to be downloaded.\nAppendix H. TCGA2BED datasets organization\n\nFolders available inside TCGA2BED ftp (ftp://bioinf.iasi.cnr.it/) in bed format are:\n\n### Indice di /bed/\n\n<table>\n<thead>\n<tr>\n<th>Nome</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>[directory principale]</td>\n</tr>\n<tr>\n<td>acc/</td>\n</tr>\n<tr>\n<td>blca/</td>\n</tr>\n<tr>\n<td>brca/</td>\n</tr>\n<tr>\n<td>cesc/</td>\n</tr>\n<tr>\n<td>chol/</td>\n</tr>\n<tr>\n<td>coad/</td>\n</tr>\n<tr>\n<td>dlbc/</td>\n</tr>\n<tr>\n<td>esca/</td>\n</tr>\n<tr>\n<td>gbm/</td>\n</tr>\n<tr>\n<td>hncs/</td>\n</tr>\n<tr>\n<td>kich/</td>\n</tr>\n<tr>\n<td>kirc/</td>\n</tr>\n<tr>\n<td>kirp/</td>\n</tr>\n<tr>\n<td>laml/</td>\n</tr>\n<tr>\n<td>lgg/</td>\n</tr>\n<tr>\n<td>lihc/</td>\n</tr>\n<tr>\n<td>luad/</td>\n</tr>\n<tr>\n<td>lusc/</td>\n</tr>\n<tr>\n<td>meso/</td>\n</tr>\n<tr>\n<td>ov/</td>\n</tr>\n<tr>\n<td>paad/</td>\n</tr>\n<tr>\n<td>pcpg/</td>\n</tr>\n<tr>\n<td>prad/</td>\n</tr>\n<tr>\n<td>read/</td>\n</tr>\n<tr>\n<td>sarc/</td>\n</tr>\n<tr>\n<td>skcm/</td>\n</tr>\n<tr>\n<td>stad/</td>\n</tr>\n<tr>\n<td>tgct/</td>\n</tr>\n<tr>\n<td>thca/</td>\n</tr>\n<tr>\n<td>thym/</td>\n</tr>\n<tr>\n<td>uccc/</td>\n</tr>\n<tr>\n<td>ucs/</td>\n</tr>\n<tr>\n<td>uvm/</td>\n</tr>\n</tbody>\n</table>\n\nWhere inside any one of these folders we find the following structure:\n\n### Indice di /bed/*/\nTCGA2BED datasets organization\n\nAlso inside the mirnaseq folder the inner structure is:\n\nIndice di /bed/*/mirnaseq/\n\n<table>\n<thead>\n<tr>\n<th>Nome</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>[directory principale]</td>\n</tr>\n<tr>\n<td>isoform.quantification/</td>\n</tr>\n<tr>\n<td>mirna.quantification/</td>\n</tr>\n</tbody>\n</table>\n\nOrder for the rnaseq folder:\n\nIndice di /bed/*/rnaseq/\n\n<table>\n<thead>\n<tr>\n<th>Nome</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>[directory principale]</td>\n</tr>\n<tr>\n<td>exon.quantification/</td>\n</tr>\n<tr>\n<td>gene.quantification/</td>\n</tr>\n<tr>\n<td>spljxn.quantification/</td>\n</tr>\n</tbody>\n</table>\n\nAnd for the rnaseqv2 folder follows this order:\n\nIndice di /bed/*/rnaseqv2/\n\n<table>\n<thead>\n<tr>\n<th>Nome</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>[directory principale]</td>\n</tr>\n<tr>\n<td>exon.quantification/</td>\n</tr>\n<tr>\n<td>gene.quantification/</td>\n</tr>\n<tr>\n<td>isoform.quantification/</td>\n</tr>\n<tr>\n<td>spljxn.quantification/</td>\n</tr>\n</tbody>\n</table>\n\nInside any folder in the following list (* meaning any subfolder):\nTCGA2BED datasets organization\n\n- /bed/*/cnv/\n- /bed/*/dnamethylation27/\n- /bed/*/dnamethylation450/\n- /bed/*/dnaseq\n- /bed/*/mirnaseq/isoform.quantification/\n- /bed/*/mirnaseq/mirna.quantification/\n- /bed/*/rnaseqv2/exon.quantification/\n- /bed/*/rnaseqv2/gene.quantification/\n- /bed/*/rnaseqv2/isoform.quantification/\n- /bed/*/rnaseqv2/spljxn.quantification/\n\nEvery folder inside contains:\n\n- exp_info.tsv: contains nº of experiment files in the folder.\n- header.schema: region data file schema.\n- md5table.txt: contains md5 checksum for every file inside the folder.\n- File1.bed (data file)\n- File1.bed.meta (metadata file)\n- (...more files .bed and .bed.meta)\nAppendix I. ENCODE metadata generation for experiment JSON\n\nFor the ENCODE project, the metadata of every experiment is distributed in a tree structure of items (item is the base object for every entity in ENCODE, so any object inherits from it), the root node item is the experiment. Experiment inherits from dataset that is another item in the ENCODE project and also implements other properties. Metadata generation is done in 3 sections, first section is ENCODE’s “Shared calculated properties” and mixin properties, this section explains which general attributes (mixin and shared calculated properties are used among many items in ENCODE) are contained inside every experiment. Second section is dataset specific properties that contain the experiment. Third section comprehends the experiment specific information. The 4th section in this appendix summarizes the usage of ENCODE JSON metadata and its possibilities. The final section explains the substructures used in the first 3 sections described in this appendix.\n\nI.1. Shared Calculated and Mixin Properties\n\nThese properties are common ENCODE utilities used by many items, 2 files are used to explain this in the ENCODE documentation: shared_calculated_properties.py and mixins.json. And the information that could be added by these utilities is the following:\n\n- submitted_by: id of the user who created the item, is auto assigned by the server and it is also a link to the same user.\n- date_created: date and time for the creation of the item, is auto assigned by the server.\n\n---\n\n1 [https://github.com/ENCODE-DCC/encoded/blob/master/src/encoded/types/shared_calculated_properties.py](https://github.com/ENCODE-DCC/encoded/blob/master/src/encoded/types/shared_calculated_properties.py)\n\n• submitter_comment: additional information specified by the submitter to be displayed as a comment on the portal.\n\n• biosample_term_id: ontology id describing the biosample.\n\n• biosample_term_name: ontology term describing biosample.\n\n• biosample_synonyms: set of other terms in the ontology that describe the biosample.\n\n• biosample_type: categorization of the biosample, is a value from the following enumeration (\"primary cell\", \"immortalized cell line\", \"tissue\", \"in vitro differentiated cells\", \"induced pluripotent stem cell line\", \"whole organisms\", \"stem cell\").\n\n• developmental_slims: set of ontology terms referring to the category “developmental” associated to the biosample_term_id.\n\n• organ_slims: set of terms in the ontology that refer to the organ associated with the biosample_term_id.\n\n• accession: unique identifier to be used to reference the object.\n\n• alternate_accessions: set of accessions previously assigned to objects that have been merged with this object.\n\n• accessioned_status: status of the accession, value in the enum “in progress”, “deleted”, “replaced”, “released”, “revoked”.\n\n• notes: DCC (Data Coordinating Center) internal notes.\n\n• lab: laboratory associated with the submission.\n\n• award: grant associated with the submission.\n- **uuid**: universally unique identifier (UUID) is a 128-bit number used to identify information in computer systems.\n\n- **references**: publications that provide more information about the object. It is an set of links to the references.\n\n- **system_slims**: preferred name on the ontology for the system which the biosample_term_id belongs.\n\n- **schema_version**: the version of the JSON schema that the server uses to validate the object.\n\n- **aliases**: set of lab specific identifiers to reference an object. Current convention is colon separated lab name and lab identifier.\n\n\n### 1.2. Dataset Properties\nProperties of dataset item in ENCODE. The metadata generation is done mainly with 2 files: the schema dataset.json\\(^3\\) and the python script dataset.py\\(^4\\). The information that could be added by this section are (shared calculated and mixin properties are not shown in the list):\n\n- **description**: plain text description of the dataset.\n- **dbxrefs**: set of unique identifiers from external resources.\n- **internal_tags**: some datasets are part of particular data collections. Those collections are the following tags: “DREAM”, “ENCORE”, “ENTEx”, “SESCC”, “dbGaP”, “ENCYCLOPEDIAv3”, “ENCYCLOPEDIAv4”, “cre_inputv10”, “cre_inputv11”. This property is a set.\n- **date_released**: autogenerated date and time assigned when the object is released.\n- **contributing_files**: set of files used to create the dataset. Includes “released” and excludes “revoked”, “deleted” and “replaced” files.\n- **original_files**: set of files used to create the dataset. Includes every file status.\n- **hub**: section of the lab where the dataset was created.\n- **annotations**: set of annotation files produced by ENCODE.\n- **superseded_by**: set of datasets that replace this dataset.\n- **assembly**: GRC genome assembly to which the target coordinates relate. E.g. GRCh38. It is an set created from all the assemblies referred in every file in the dataset’s files.\n\n\\(^3\\)https://github.com/ENCODE-DCC/encoded/blob/master/src/encoded/schemas/dataset.json\n\n\\(^4\\)https://github.com/ENCODE-DCC/encoded/blob/master/src/encoded/types/dataset.py\n- **month_released**: calculated month extracted from date_released.\n\nWhen embedded JSON is requested extra metadata is added, this dataset properties include:\n\n(Dots indicate the right term is contained inside the left one and plurals denote set of items)\n\n- **files**: set of files used to create the dataset. Includes “released” and “archived” files and excludes “revoked”, “deleted” and “replaced”. For every file, also contains the following properties:\n - replicate\n - replicate.experiment\n - replicate.experiment.lab\n - replicate.experiment.target\n - submitted_by\n - lab\n\n- **revoked_files**: set of files used in the creation of the dataset but have been replaced. Includes “revoked” only files. For every file also contains the following properties:\n - replicate\n - replicate.experiment\n - replicate.experiment.lab\n - replicate.experiment.target\n - submitted_by\nlab\n\n- award.pi.lab: lab associated with the principle Investigator (pi) of the grant (award).\n- lab: lab where the experiment comes from.\n- documents.lab: lab where each document used in the experiment come from.\n- documents.award: grant associated to each document used in the dataset.\n- documents.submitted_by: user who submitted each document.\n- references: publications that provide more information about the dataset.\n\nI.3. Experiment Properties\n\nProperties of experiment item in ENCODE. The metadata generation is done mainly by 2 files: the schema experiment.json\\(^5\\) and the python script experiment.py\\(^6\\). An experiment is a special case of dataset. It includes assay metadata, replicate information and data files. It could add the following properties (shared calculated, mixin and dataset properties are not shown):\n\n- target: for assays, such as ChIP-seq or RIP-seq, the name of the gene whose expression or product is under investigation for the experiment.\n- biosample_type: categorization of the biosample.\n- documents: protocols or other documents that describe the assay or the results.\n- supersedes: experiment(s) that this experiment supersedes by virtue of being newer, better etc. than the one(s) it supersedes.\n\n\\(^5\\)https://github.com/ENCODE-DCC/encoded/blob/master/src/encoded/schemas/experiment.json\n\\(^6\\)https://github.com/ENCODE-DCC/encoded/blob/master/src/encoded/types/experiment.py\n- **internal_status**: status of an experiment in the DCC process.\n\n- **pipeline_error_detail**: explanation of why the experiment failed pipeline analysis.\n\n- **possible_controls**: set of experiments that contain files that can serve as scientific controls for this experiment.\n\n- **assay_title**: gets the preferred term in the ontology for the assay title based in assay_term_id.\n\n- **replication_type**: indicates the replication type used for the assay.\n\n- **assay_slims**: preferred term for the assay in the ontology.\n\n- **category_slims**: preferred term for the category in the ontology.\n\n- **objective_slims**: preferred name for the objective in the ontology.\n\n- **assay_term_id**: ENCODE id referring to assay_term_name.\n\n- **type_slims**: preferred term for the type in the ontology.\n\n- **related_files**: to be removed in a future release after data cleanup.\n\nWhen embedded JSON is requested extra metadata is added, experiment properties include all the properties of the dataset plus:\n\n(Dots indicate the right term is contained inside the left one and plurals denote set of items)\n\n- **files** (appends to the files subcategory in dataset):\n - **platform**: measurement device used to collect data\n\n - **analysis_step_version.analysis_step**\nENCODE metadata generation for experiment JSON\n\n- analysis_step_version.analysis_step.documents\n- analysis_step_version.analysis_step.documents.award\n- analysis_step_version.analysis_step.documents.lab\n- Analysis_step_version.analysis_step.documents.submitted_by\n\n- replicates (appends to the replicates subcategory in dataset):\n - library\n - library.documents.lab\n - library.documents.submitted_by\n - library.documents.award\n - library.biosample.submitted_by\n - library.biosample.source\n - library.biosample.documents\n - library.biosample.organism\n - library.biosample.donor\n - library.biosample.donor.organism\n - library.biosample.genetic_modifications\n - library.biosample.genetic_modifications.target\n - library.biosample.genetic_modifications.modification_techniques\n - library.biosample.genetic_modifications.treatments\n - library.treatments\nAnd many more attributes of lab, award and submitted by for the library.biosample\n\nI.4. Extracting the metadata\n\nThe acquisition of the metadata is done by downloading the JSON of an experiment provided by the ENCODE API and is requested with the frame “embedded” which is explained before. For the useful extraction of the metadata the experiment JSON has to be filtered as it contains much more information that is not related to the file being examined. Therefore sections that summarize data from multiple files together have to be consistent with the file being downloaded by filtering out the information related to other files. Also information as the legal documents for the laboratories or the different grants that were won for the development of the project are meaningless when referring to a file’s metadata.\n\nWith the complete structure of the organization for the metadata is clearer which properties belongs to experiment, dataset or shared calculated and mixin properties.\n\nThe complete structure of the JSON attribute is known by now; but the usability of the metadata to be extracted depends on the final purpose of the processing of those metadata. More complex analysis of this source’s information should be performed to allow a better integration of the ENCODE metadata with other sources’ metadata.\n\nI.5. More child nodes in ENCODE metadata\n\nThe following is a list of encode items mentioned before with their nested properties explained, obtained from the encode GitHub directories schemas and types. These items are part of the ENCODE JSON metadata structure and these items are nested inside the structures explained before in this appendix:\n\n7https://github.com/ENCODE-DCC/encoded\n8https://github.com/ENCODE-DCC/encoded/tree/master/src/encoded/schemas\n9https://github.com/ENCODE-DCC/encoded/tree/master/src/encoded/types\n(Plurals denote set of items, unexplained items are assumed to be auto explanatory)\n\n- **user**\n - email\n - first_name\n - last_name\n - lab: lab user is primarily associated with.\n - submits_for: labs user is authorized to submit data for.\n - groups: additional access control groups.\n - viewing_groups: the group that determines which set of data the user has permission to view.\n - other user info such as skype, telephone, etc.\n\n- **lab**\n - name: short unique name for the lab, current convention is lower cased and hyphen delimited of PI's first and last name (e.g. john-doe).\n - title: unique name for affiliation identification, current convention is comma separated PI's first & last name and institute label. (e.g. John Doe, UNI).\n - pi: principle investigator (user) of the lab.\n - awards: grants associated with the lab.\n - institute_label\n - other laboratory information such as address, institute_name, city, etc.\n\n- **award**\n- title: grant name from the NIH database, if applicable.\n\n- name: official grant number from the NIH database, if applicable.\n\n- description.\n\n- start_date.\n\n- end_date.\n\n- url.\n\n- other grant information such as viewing_group, project, url.\n\n- reference\n \n - reference_type: category that best describes the reference set.\n\n - organism.\n\n - software_used: list of software used to derive the reference file set.\n\n- annotation\n \n - annotation_type: category that best describes the annotation set.\n\n - encyclopedia_version: version of the ENCODE encyclopedia to which this annotation belongs.\n\n - organism.\n\n - relevant_timepoint: time point for which the annotation is relevant.\n\n - relevant_timepoint_units.\n\n - relevant_life_stage: life_stage for which the annotation is relevant.\ntargets: for predictions of particular features (e.g. distribution of a histone mark), specify the predicted feature(s).\n\nsoftware_used: list of software used to derive the annotation calls.\n\nsupersedes: annotation set(s) that this annotation set supersedes by virtue of being newer, better etc. than the one(s) it supersedes.\n\n- file\n \n accession.\n\n external_accession.\n\n read_count: number of reads in fastq file.\n\n fastq_signature: fastq file flowcell based unique signature to reference a file.\n\n file_format.\n\n file_format_type: files of type bed and gff require further specification.\n\n file_format_specifications: text or .as files (document) the further explain the file format.\n\n restricted: flag to indicate whether this file is subject to restricted access.\n\n md5sum: md5sum of the file being transferred.\n\n content_md5sum: MD5sum of the uncompressed file.\n\n file_size.\n\n platform: measurement device used to collect data.\n- **read_length**: for high-throughput sequencing, the number of contiguous nucleotides determined by sequencing.\n\n- **mapped_read_length**: the length of the reads actually mapped, if the original read length was clipped.\n\n- **mapped_run_type**: mapped run type of the alignment file which may differ from the fastqs it is derived from.\n\n- **flowcell_details**: for high-throughput sequencing, the flowcells used for the sequencing of the replicate.\n\n- **output_type**: description of the file's purpose or contents.\n\n- **run_type**: indicates if file is part of a single or paired run.\n\n- **paired_end**: which pair the file belongs to (if paired end library).\n\n- **derived_from**: files participating as inputs into software to produce this output file.\n\n- **controlled_by**: files that control this file.\n\n- **supersedes**: files that this file replaces.\n\n- **paired_with**: file that corresponds with this file.\n\n- **dataset**: experiment or dataset the file belongs to.\n\n- **replicate**: experimental replicate designation for the file.\n\n- **assembly**: genome assembly that files were mapped to.\n\n- **genome_annotation**: genome annotation that file was generated with.\n\n- **submitted_file_name**: local file name used at time of submission.\n- status: one among “uploading”, “uploaded”, “upload failed”, \"format check failed\", \"in progress\", \"deleted\", \"replaced\", \"revoked\", \"archived\", \"released\" and \"content error\".\n\n- dbxrefs: unique identifiers from external resources.\n\n- step_run: run instance of the step the file was generated from.\n\n- content_error_detail: explanation of why the file failed the automated content checks.\n\n- replicate\n\n - antibody: for Immunoprecipitation assays, the antibody used.\n\n - biological_replicate_number: data collection under the same methods using a different biological source, measuring the variability in the biological source.\n\n - technical_replicate_number: data collection under the same methods using the same biological source, measuring the variability in the method.\n\n - experiment: experiment the replicate belongs to.\n\n - library: nucleic acid library used in this replicate.\n\n - rbns_protein_concentration: for use only with RNA Bind-n-Seq replicates to indicate the protein concentration.\n\n - rbns_protein_concentration_units: unit for the dependant rbns_protein_concentration.\n\n - status: one among \"in progress\", \"deleted\", \"released\", \"preliminary\", \"proposed\", \"archived\", \"revoked\".\n\n - target.\n- dbxref: unique identifier from external resource.\n- organism: organism bearing the target.\n- gene_name: HGNC or MGI identifier for the target.\n- label: common name for the target including post-translational modifications, if any.\n- investigated_as: context(s) the target was investigated in.\n- status: one among “proposed”, “current”, “deleted”, “replaced”.\n\n• document\n - document_type: category that best describes the document.\n - description: plain text description of the document.\n - urls: external resources with additional information to the document.\n\n• platform\n - term_id: OBI (Ontology for Biomedical Investigations) ontology identifier for the measurement device.\n - term_name: OBI (Ontology for Biomedical Investigations) ontology term for the measurement device.\n - dbxrefs: unique identifiers from external resources.\n - url: external resource with additional information about the measurement device.\n\n• analysis_step\n - name: unique name of the analysis step.\no title: preferred viewable name of the analysis step, likely the same as the name.\n\no analysis_step_types: classification of the software.\n\no input_file_types: file types used as input for the analysis.\n\no output_file_types: file types generated as output for the analysis.\n\no qa_stats_generated: the QA statistics generated by the analysis.\n\no parents: the precursor steps.\n\n• analysis_step_run\n\n o analysis_step_version: reference to template step in pipeline\n\n o dx_applet_details: metadata capture from DNA Nexus applets.\n\n o status: one among “waiting”, “running”, “finished”, “error”, “virtual”.\n\n• analysis_step_version\n\n o version: version of the analysis step.\n\n o analysis_step: reference to template step in pipeline.\n\n o software_versions: software version used in the analysis.\n\n• source\n\n o description: plain text description of the source.\n\n o title: complete name of the originating lab or vendor.\n\n o name: auto generated from the title as lower cased and hyphen delimited.\n\n o url: external resource with additional information about the source.\n• library\n o accession.\n o spikeins_used: datasets containing the fasta and the concentrations of the library spike-ins.\n o biosample: the biosample that nucleic acid was isolated from to generate the library.\n o product_id: the product identifier provided by the vendor, for nucleic acids or proteins purchased directly from a vendor (e.g. total RNA).\n o lot_id: the lot identifier provided by the vendor, for nucleic acids or proteins purchased directly from a vendor (e.g. total RNA).\n o source: the vendor, for nucleic acids or proteins purchased directly from a vendor (e.g. total RNA).\n o nucleic_acid_term_name: SO (Sequence Ontology) term best matching the molecule isolated to generate the library (e.g. 'RNA' for a total RNA library, even if that library is subsequently reverse transcribed for DNA sequencing).\n o dbxrefs: unique identifiers from external resources.\n o nucleic_acid_starting_quantity: starting amount of nucleic acid before selection and purification.\n o nucleic_acid_starting_quantity_units: units used for starting amount of nucleic acid.\n o extraction_method: short description or reference of the nucleic acid extraction protocol used in library preparation, if applicable.\n- fragmentation_method: short description or reference of the nucleic acid fragmentation protocol used in library preparation, if applicable.\n- fragmentation_date: The date that the nucleic acid was fragmented.\n- library_size_selection_method: short description or reference of the size selection protocol used in library preparation, if applicable.\n- lysis_method: short description or reference of the cell lysis protocol used in library preparation, if applicable.\n- crosslinking_method: short description or reference of the crosslinking protocol used in library preparation, if applicable.\n- size_range: measured size range of the purified nucleic acid, in bp.\n- treatments.\n- depleted_in_term_name: SO (Sequence Ontology) term best matching the nucleic acid that was diminished from the library.\n\n- organism\n - name: short unique name for the organism (e.g. 'mouse' or 'human').\n - scientific_name: genus species for the organism (e.g. 'Mus musculus').\n - taxon_id: NCBI taxon ID for the organism (e.g. 10090).\n\n- biosample\n - accession.\n- description: plain text description of the biosample. Do not include experiment details, constructs or treatments.\n\n- constructs: expression or targeting vectors stably or transiently transfected (not RNAi or TALEN).\n\n- rnas: RNAi vectors stably or transiently transfected.\n\n- talens: TALEN constructs used to modify the biosample\n\n- treatments.\n\n- dbxrefs: unique identifiers from external resources.\n\n- documents: documents that describe the biosample preparation.\n\n- donor.\n\n- organism.\n\n- passage_number: calculating passage number, include passages from the source.\n\n- depleted_in_term_name: UBERON (Uber Anatomy Ontology) term best matching the tissue(s)/body part(s) that were removed from the biosample.\n\n- model_organism_mating_status: mating status of the animal.\n\n- internal_tags: some biosamples are part of particular data collections.\n\n- derived_from: biosample that the sample derives from via a construct or treatment.\n\n- pooled_from: biosamples from which aliquots were pooled to form the biosample.\n- **part_of**: biosample from which a discrete component was taken. That component is this biosample.\n\n- **host**: biosample that was hosting this biosample.\n\n- **subcellular_fraction_term_name**: GO (Gene Ontology) term name for cellular component that constitutes the biosample.\n\n- **phase**: cell-cycle phase.\n\n- **transfection_type**: persistence of the transfection construct.\n\n- **transfection_method**: how the transfection was performed on the biosample to introduce the construct or RNAi.\n\n- **culture_harvest_date**: for cultured samples, the date the biosample was taken.\n\n- **culture_start_date**: for cultured samples, the date the culture was started. For cell lines, the date this particular growth was started, not the date the line was established.\n\n- **date_obtained**: for tissue samples, the date the biosample was taken.\n\n- **starting_amount**: initial quantity of cells or tissue obtained.\n\n- **starting_amount_units**.\n\n- **url**: external resource with additional information about the biosample.\n\n- **model_organism_sex**: model_organism_sex is not valid for a human biosample.\n\n- **mouse_life_stage**: mouse_life_stage is not valid for a human biosample.\n\n- **fly_life_stage**: fly_life_stage is not valid for a human biosample.\n- fly_synchronization_stage: stage at which flies were synchronized.\n\n- post_synchronization_time: use in conjunction with fly_synchronization_stage or worm_synchronization_stage to specify time elapsed post-synchronization.\n\n- post_synchronization_time_units: use in conjunction with post_synchronization_time to specify time elapsed post-synchronization.\n\n- post_treatment_time: use in conjunction with treatment to specify time elapsed post-treatment.\n\n- post_treatment_time_units: use in conjunction with treatment to specify time elapsed post-treatment.\n\n- worm_life_stage: worm_life_stage is not valid for a human biosample.\n\n- worm_synchronization_stage: stage at which worms were synchronized.\n\n- model_organism_age: age or age range of the model donor organism when biological material was sampled.\n\n- model_organism_age_units: model_organism_age_units are not valid for a human biosample.\n\n- model_organism_health_status: model_organism_health_status is not valid for a human biosample.\n\n- status: one among \"in progress\", \"deleted\", \"replaced\", \"released\", \"re-voked\", \"preliminary\", \"proposed\"\n\n- donor\n\n - accession.\n\n - organism: organism of the donor.\n- url: an external resource with additional information about the donor.\n- internal_tags: some donors are part of particular data collections.\n\n- genetic_modification\n - url: external resource with additional information about the modification.\n - target: name of the gene whose expression or product is modified by the genetic modification.\n - modified_site: genomic coordinates of the modification (assembly, chromosome, start, end).\n - description: plain text description of the genetic modification.\n - modification_type: type of the genetic modification.\n - purpose: purpose of the genetic modification.\n - zygosity: zygosity of the genetic modification.\n - modification_techniques: genetic modification technique(s)/tool(s) used to perform the modification.\n - treatments: treatment(s) used to perform the genetic modification.\n\n- modification_techniques\n - dbxrefs: unique identifiers from external resources.\n\n- antibody_lot\n - accession.\n - lot_id: lot identifier provided by the originating lab or vendor.\n- lot_id_alias: lot identifiers for this lot deemed to be exactly the same by the vendor.\n\n- antigen_description: plain text description of the antigen used in raising the antibody (e.g. amino acid residue locations of the antigen).\n\n- antigen_sequence: amino acid sequence of the antigen.\n\n- clonality: diversification of the immune cell lineage to make the antibody.\n\n- dbxrefs: unique identifiers from external resources.\n\n- host_organism: organism the antibody was grown in.\n\n- isotype: class of antibody (e.g. IgA, IgD, IgE, IgG or IgM).\n\n- purifications: purification protocols used to isolate the antibody.\n\n- targets: name of the gene whose expression or product is the intended goal of the antibody.\n\n- url: external resource with additional information about the antibody.\n\n- treatment\n\n - lab: lab associated with the submission.\n\n - documents: documents that describe the treatment protocol.\n\n - dbxrefs: unique identifiers from external resources.\n\n - amount: amount of treatment applied.\n\n - amount_units.\n\n - duration.\n\n - duration_units.\n- temperature.\n- temperature_units.\n- biosamples_used: biosamples used in this treatment.\n- antibodies_used: antibodies used in this treatment.\n\n- **talen**\n - name: name of the TALEN construct.\n - description: plain text description of the TALEN construct.\n - url: external resource with additional information about the construct.\n - vector_backbone_name: cloning vector used to make the construct. E.g. PEGFP (delGFP-TAL2-truncNLS)\n - RVD_sequence: The repeat variable diresidue sequence. E.g. NI,NG,NI,HD,NG,NN,NG,NN,HD,NI,NI,NI,NI,NM,HD,HD,NG.\n - target_sequence: target genome sequence recognized by the TALE domain.\n - talen_platform: TALEN platform used to make the construct. E.g. Golden Gate.\n - target_genomic_coordinates: genomic coordinates where the TALEN cuts.\n - pairings: list of possible pairings with other TALENs.\n\n- **rnai**\n - rnai_type: classification of the interfering RNA (e.g. shRNA or siRNA).\n - url: external resource with additional information about the RNAi construct.\n- target: name of the gene whose expression or product is modified by the RNAi construct.\n- vector_backbone_name: name of the vector backbone used for the construct.\n- rna_sequence: sequence of the inhibitory RNA.\n- rna_target_sequence: genomic sequence targeted by the RNA.\n- construct:\n - construct_type: type of sequence expressed from the construct.\n - description: plain text description of the construct. May include backbone name, description of the insert or purpose of the construct.\n - url: external resource with additional information about the construct.\n - target: name of the gene whose expression or product is modified by the construct.\n - tags: recombinant tags in the construct.\n - vector_backbone_name: name of the vector backbone used for the construct.\n - genomic_integration_site: genomic coordinates where construct is integrated, if known.\n - insert_sequence: DNA sequence inserted into the vector backbone.\n - insert_genome_coordinates: genomic coordinates of the insert. e.g. GRCh38 or dm6.\n - promoter_used: name of the gene that the promoter regulates natively.\no **promoter_genome_coordinates:** genomic coordinates of the promoter. Use NCBI assembly version:chromosome number:nucleotide range (e.g. WBcel235:III:1433720-1434340).\n\no **promoter_position_relative_to_target:** relative distance of promoter sequence in the construct upstream of the target gene TSS.\nAppendix J. Console manual for GMQLImporter\n\nTo run GMQLImporter is done by command line by invoking the following line:\n\n(Assuming the compiled Scala code is in GMQLImporter.jar)\n\n```\njava –jar GMQLImporter.jar configuration_xml_path gmql_conf_folder\n```\n\nwhere `configuration_xml_path` is the location for the configuration file and `gmql_conf_folder` contains the path to the folder with corresponding variables to start GMQLRepository service.\n\nIf `log` added at the end, it will show the number of executions already performed and stored in the database.\n\nIf added `log –n` where n is the n-th past execution, the statistical summary for that run is shown. Also multiple runs can be requested at the same time by separating them with comma. As example log -1, 2, 3 will show (if they exist) the last execution’s statistics, plus the statistics for the 2 executions done before, it notifies also if a number is not valid and will not show that specific information if so (as example: if 5 executions are already run, using log -6 will not show statistics but will tell the user that run does not exist).\n\nIf added –retry GMQLImporter tries to download the failed files on the local datasets.\nAppendix K. Metadata replacement for ENCODE in GMQLImporter\n\nThis is an example of metadata replacement, extract from the one used for ENCODE. This file is referred from the main configuration XML to replace by using regular expressions metadata field names in the transformation process:\n\n```xml\n<metadata_replace_list>\n <metadata_replace>\n <regex>^file\\|accession$</regex>\n <replace>File accession</replace>\n </metadata_replace>\n <metadata_replace>\n <regex>^accession$</regex>\n <replace>Experiment accession</replace>\n </metadata_replace>\n <metadata_replace>\n <regex>^file\\|file_type$</regex>\n <replace>File format</replace>\n </metadata_replace>\n <metadata_replace>\n <regex>^file\\|output_type$</regex>\n <replace>Output type</replace>\n </metadata_replace>\n <metadata_replace>\n <regex>^assay_title$</regex>\n <replace>Assay</replace>\n </metadata_replace>\n <metadata_replace>\n <regex>^biosample_term_id$</regex>\n <replace>Biosample term id</replace>\n </metadata_replace>\n <metadata_replace>\n <regex>^biosample_term_name$</regex>\n <replace>Biosample term name</replace>\n </metadata_replace>\n</metadata_replace_list>\n```"}}},{"rowIdx":92,"cells":{"id":{"kind":"string","value":"36990ed48137623b7a1706eb9e50f944a2ff772b"},"text":{"kind":"string","value":"Language theory of lambda-calculus with recursive types\n\nCitation for published version (APA):\nLanguage Theory of a $\\lambda$–calculus\nwith Recursive Types\nby\nH.M.M. ten Eikelder\nR.H. Mak\n\n88/14\n\njune 1988\nThis is a series of notes of the Computing Science Section of the Department of Mathematics and Computing Science Eindhoven University of Technology. Since many of these notes are preliminary versions or may be published elsewhere, they have a limited distribution only and are not for review. Copies of these notes are available from the author or the editor.\nIt is not uncommon to design a programming language by regarding the kind of computations one would like to perform and to decide on a style of notation. Thus one arrives at a syntactic definition of the language which in general contains a large number of constructs and which, for the purpose of expressing ones computations, is usually very satisfying. However, when it comes to assigning a precise meaning to the syntactic constructs thus arrived at, the problems soon become tremendous. Therefore it seems more appropriate to investigate what the proper mathematical abstractions are to model ones computations with and to see in which way they should be manipulated. Thus a carefully chosen (preferably small) number of semantic constructs should dictate the basic syntactic ingredients of a kernel language. Ease of programming can be obtained by adding an additional layer of syntactic sugar to this kernel language. Since the latter is defined in terms of the basic syntactic constructs, it is not hard to define its semantics. Our ultimate goal is to design a language along these lines. Our interest is not so much in the resulting language, however, but rather in the design process itself. As the kernel for our language we have opted for the lambda-calculus, because of its simple nature, extended with a rich type structure, that should allow for instance polymorphism and recursively defined types. There are several approaches known in the literature such as languages with implicit types like ML [HMcQM86] or languages with explicit types as described in [Re85]. In this report we make a start towards the latter in the sense that the language we define does contain recursive types and what is known as a polymorphic let-construct. It does not contain, however, expressions which are 'type-abstractions'. We have chosen this cautious approach, since the semantics of second order lambda calculi with recursive types is not yet well understood, although various results are known [McQPS86,McC79,Me86,Mi71]. Therefore we study this relatively simple case in great detail before we turn our attention towards 'full' polymorphism. Moreover, we have included both strict and non-strict versions of our type constructors. Investigation of their semantic properties will enable us to make the proper choice in a latter stage when we design the actual language.\nCHAPTER 0\n\nThe structure of this report is as follows. In chapter 1 the language is given and the meaning of its constructs is briefly explained. A comprehensive and formal semantics is given in chapters 4 and 5 for the type expressions and expressions proper respectively. In chapter 2 a type deduction system is given that enables us to keep the type information within expressions to a minimum. Chapter 3 states a set of reduction rules whose soundness is proven in chapter 6. These rules can be viewed as an operational semantics of our language. Finally, in chapter 7, it is shown that a typed version of the Curry fixed point combinator [Ba81,HiSe86] can be defined in the language.\n1. SYNTAX OF TYPE EXPRESSIONS AND EXPRESSIONS\n\nThe language we consider consists of expressions that contain type information. Its formal syntax is given by two kinds of expressions, type expressions and expressions proper. Let Tvar be a countable infinite set of variables. Elements of Tvar will be called type variables. Type expressions are generated by the following rules.\n\nT1. \\[ \\text{Texp} ::= \\Omega \\]\nT2. \\[ \\text{Texp} ::= \\text{Tvar} \\]\nT3. \\[ \\text{Texp} ::= \\mathcal{Texp} \\]\nT4.1. \\[ \\text{Texp} ::= (\\text{Texp} + \\text{Texp}) \\]\nT4.2. \\[ \\text{Texp} ::= (\\text{Texp} \\odot \\text{Texp}) \\]\nT5.1. \\[ \\text{Texp} ::= (\\text{Texp} \\times \\text{Texp}) \\]\nT5.2. \\[ \\text{Texp} ::= (\\text{Texp} \\otimes \\text{Texp}) \\]\nT6.1. \\[ \\text{Texp} ::= (\\text{Texp} \\rightarrow \\text{Texp}) \\]\nT6.2. \\[ \\text{Texp} ::= (\\text{Texp} \\ominus \\text{Texp}) \\]\nT7. \\[ \\text{Texp} ::= \\nu(\\Lambda \\text{Tvar} | \\text{Texp}) \\]\n\nA formal semantics, which associates a domain (c.p.o.) to every type expression, will be defined in section 4. We now give an informal description of the domains corresponding to type expressions generated by T1 - T7. The type expression \\( \\Omega \\) corresponds to the one point domain. The symbol \\( \\mathcal{T} \\) is used to denote lifting of the domain, i.e. appending a fresh bottom element. Further +, \\times, \\rightarrow correspond to the disjoint sum, cartesian product and function space domain constructors, whereas \\( \\oplus, \\otimes, \\ominus \\) correspond to their strict versions, i.e. the coalesced sum, smash product and space of strict functions. A type expression of the form \\( \\nu(\\Lambda \\text{t} \\mid \\text{te}) \\) describes a recursively defined type. For instance the type expression \\( \\nu(\\Lambda \\text{t} \\mid (\\text{t} + \\text{t})) \\) corresponds to a domain D such that D is isomorphic to the disjoint sum of D and D; the type expression \\( \\nu(\\Lambda \\text{t} \\mid (\\mathcal{T}\\Omega \\oplus \\text{t})) \\) describes the flat domain of natural numbers. Whether an actual programming language should contain all the type constructors above remains to be seen. However, it is precisely the intention of this paper to investigate the properties of\nthe various constructs in order to allow a deliberate choice.\n\nLet \\( \\text{Var} \\) be a countable infinite set of variables such that \\( \\text{Var} \\cap \\text{Tvar} = \\emptyset \\). The syntax of expressions is given by the following rules.\n\n\\[\n\\begin{align*}\n\\text{E1. } & \\quad \\text{Exp} ::= (\\text{btm}\\mid \\text{Ex})^* \\\\\n\\text{E2. } & \\quad \\text{Exp} ::= \\text{Var}^* \\\\\n\\text{E3.1. } & \\quad \\text{Exp} ::= (\\text{up}\\ \\text{Exp})^* \\\\\n\\text{E3.2. } & \\quad \\text{Exp} ::= (\\text{down}\\ \\text{Exp})^* \\\\\n\\text{E4.1.1. } & \\quad \\text{Exp} ::= (\\text{inl}\\ \\text{Exp} \\mid \\text{Ex})^* \\\\\n\\text{E4.1.2. } & \\quad \\text{Exp} ::= (\\text{inr}\\ \\text{Ex} \\mid \\text{Exp})^* \\\\\n\\text{E4.1.3. } & \\quad \\text{Exp} ::= (\\text{sum}\\ \\text{Exp}\\ \\text{Exp})^* \\\\\n\\text{E4.2.1. } & \\quad \\text{Exp} ::= (\\text{inls}\\ \\text{Exp} \\mid \\text{Ex})^* \\\\\n\\text{E4.2.2. } & \\quad \\text{Exp} ::= (\\text{inrs}\\ \\text{Ex} \\mid \\text{Exp})^* \\\\\n\\text{E4.2.3. } & \\quad \\text{Exp} ::= (\\text{sums}\\ \\text{Exp}\\ \\text{Exp})^* \\\\\n\\text{E5.1.1. } & \\quad \\text{Exp} ::= (\\text{prol}\\ \\text{Exp})^* \\\\\n\\text{E5.1.2. } & \\quad \\text{Exp} ::= (\\text{pror}\\ \\text{Exp})^* \\\\\n\\text{E5.1.3. } & \\quad \\text{Exp} ::= (\\text{prod}\\ \\text{Exp}\\ \\text{Exp})^* \\\\\n\\text{E5.2.1. } & \\quad \\text{Exp} ::= (\\text{prols}\\ \\text{Exp})^* \\\\\n\\text{E5.2.2. } & \\quad \\text{Exp} ::= (\\text{prors}\\ \\text{Exp})^* \\\\\n\\text{E5.2.3. } & \\quad \\text{Exp} ::= (\\text{prods}\\ \\text{Exp}\\ \\text{Exp})^* \\\\\n\\text{E6.1.1. } & \\quad \\text{Exp} ::= (\\lambda\\ \\text{Var} : \\text{Ex} \\mid \\text{Exp})^* \\\\\n\\text{E6.1.2. } & \\quad \\text{Exp} ::= (\\text{appl}\\ \\text{Exp}\\ \\text{Exp})^* \\\\\n\\text{E6.2.1. } & \\quad \\text{Exp} ::= (\\lambda s\\ \\text{Var} : \\text{Ex} \\mid \\text{Exp})^* \\\\\n\\text{E6.2.2. } & \\quad \\text{Exp} ::= (\\text{apps}\\ \\text{Exp}\\ \\text{Exp})^* \\\\\n\\text{E7.1. } & \\quad \\text{Exp} ::= (\\text{intro}\\ \\nu (\\text{A}\\ \\text{Tvar} \\mid \\text{Ex}) \\mid \\text{Exp})^* \\\\\n\\text{E7.2. } & \\quad \\text{Exp} ::= (\\text{elim}\\ \\nu (\\text{A}\\ \\text{Tvar} \\mid \\text{Ex}) \\mid \\text{Exp})^* \\\\\n\\text{E8. } & \\quad \\text{Exp} ::= (\\text{A}\\ \\text{Tvar} \\mid \\text{Exp})\\ \\text{Ex}^* \n\\end{align*}\n\\]\nIn chapter 2 we give a type deduction system that defines the well typed expressions. Furthermore it will be shown that every well typed expression has exactly one type (up to \\( \\alpha \\)-conversion). In chapter 5 we define the semantics of a well typed expression and show that the value of an expression is an element of the domain corresponding to its type. An operational semantics in terms of reduction rules is given in section 3.\n\nIn the rest of this chapter we give an informal description of the expressions introduced above. Let \\( te \\) be a type expression. The expression \\((\\text{btm} \\mid te)\\) stands for a nonterminating computation which does not yield any information. The expressions generated by E3 are used in connection with the lifting of domains. In particular the \\((\\text{up} \\ e)\\) construct is used to postpone reductions inside the expression \\( e \\) (see also chapter 3). The expressions defined by E4.1 are related to the disjoint sum of domains: \\((\\text{inl} \\ e \\mid te)\\) and \\((\\text{inr} \\ te \\mid e)\\) denote the injection of \\( e \\) in the left respectively right part of a sum domain. If \\( e_1 \\) and \\( e_2 \\) denote two functions with the same range, then \\((\\text{sum} \\ e_1 \\ e_2)\\) denotes a function whose domain is the disjoint sum of the domains of \\( e_1 \\) and \\( e_2 \\) and whose range is the common range of \\( e_1 \\) and \\( e_2 \\). The expressions defined by E4.2 are the strict versions of those given in E4.1, they correspond to the strict sum of domains \\((\\oplus)\\). E5.1 generates expressions which are related to the product of domains. The first two rules correspond to the left and right projection, whereas E5.1.3 corresponds to the pair construction. Again E5.2 gives the strict versions. E6.1 (and E6.2) describe (strict) lambda abstraction and application. To understand E7 consider a recursively defined type expression, for instance \\( \\nu(A \\ t \\mid t + t) \\). The domain \\( D \\) which will be associated to this type expression (see chapter 4) is isomorphic to the disjoint sum of \\( D \\) and \\( D \\). The two expressions given by E7 are the syntactic representants of these kinds of isomorphism and its inverse. Finally E8 gives the possibility of building a context of type variables which are bound to type expressions.\n\nNext we introduce some notations which will be used frequently in this report. The mapping \\( \\text{FV} : \\text{Exp} \\rightarrow \\text{Var} \\) yields the free variables of an expression. The mapping \\( \\text{FTV} : \\text{Exp} \\cup \\text{Texp} \\rightarrow \\text{Tvar} \\)\nCHAPTER 1\n\ngives the free type variables of an expression or a type expression. Recursive definitions of \\( \\text{FV} \\) and \\( \\text{FTV} \\) can easily be given, but we shall not do so here. In the sequel we shall encounter three kinds of substitution. The substitution of type expressions for type variables can be performed in type expressions and in expressions. The substitution of expressions for variables can only take place in expressions. Apart from the case of (type) expressions with bounded (type) variables the definition of substitution is straightforward. In case of substitution for a type variable in a (type) expression with a bounded type variable or substitution for a variable in an expression with a bounded variable name clashes may occur. In that case the bounded (type) variable is always replaced by the first appropriate free (type) variable. We list the instances where this happens. Let \\( s, t \\in \\text{Tvar} \\), \\( x, y \\in \\text{Var} \\), \\( t_e, t_{e1}, t_{e2} \\in \\text{Texp} \\) and \\( e, e_1, e_2 \\in \\text{Exp} \\). Then\n\n\\[\n\\begin{align*}\n- & (\\forall (\\Lambda t|t_e))_{t_{e2}}^x = (\\forall (\\Lambda \\ u |(te_1)_{u}^{t_{e2}})_{t_{e2}}^x) , \\\\\n& \\text{where } u \\text{ is the first type variable such that } u \\neq s \\text{ and } u \\notin \\text{FTV}(te_1) \\cup \\text{FTV}(te_2) . \\\\\n- & ((\\lambda x: \\text{te} \\ | e_1)^y_{e_2} = (\\lambda z: \\text{te} \\ | (e_1)^x_{z}^{y_{e_2}}) , \\\\\n& \\text{where } z \\text{ is the first variable such that } z \\neq y \\text{ and } z \\notin \\text{FV}(e_1) \\cup \\text{FV}(e_2) . \\\\\n- & ((\\Lambda t|e)_{t_{e2}}^s = ((\\Lambda u |(e_1)_{u}^{s})_{t_{e2}}^s) , \\\\\n& \\text{where } u \\text{ is the first type variable such that } u \\neq s \\text{ and } u \\notin \\text{FTV}(e) \\cup \\text{FTV}(te_1) \\cup \\text{FTV}(te_2) . \\\\\n\\end{align*}\n\\]\n\nHere \\( te \\) is the type expression which will be associated to \\( e \\) by the type inference system given in the next chapter (hence substitution is only defined for well-typed expressions).\n\nNote that our definition of substitution implies that bound variables will also be renamed in cases where this is in fact not necessary. The reason for choosing this definition, instead of a more usual one which considers several cases [Ba81], is to reduce the case analysis in the proofs further on. Finally we mention that the symbol \\( \\equiv \\) will be used to denote the syntactic equality of (type) expressions, whereas \\( \\equiv_{\\alpha} \\) will be used for the equality of (type) expressions up to renaming of the bound variables (\\( \\alpha \\)-conversion).\n2. TYPE INFERENCE\n\n2.1. Introduction.\n\nIn this chapter we demonstrate that the kernel language introduced in the previous chapter is an explicitly typed language in the sense of Reynolds[Re85]. That is, given an expression and a sequence of assumptions regarding the free variables and free type variables occurring in that expression it is possible to assert at most one type for that expression. By a type we mean a class of type expressions that are equal up to $\\alpha$–conversion. In chapter 4 it is shown that all type expressions in such a class denote the same domain.\n\n2.2. Formal type inference system.\n\nFormula's of the type inference system will be called typings and they are constructed according to the following grammar rules:\n\n\\begin{align*}\nI1. & \\quad \\text{Typing} \\quad ::= \\text{Assumptions} \\rightarrow \\text{Consequences} \\cdot \\\\\nI2.1. & \\quad \\text{Assumptions} \\quad ::= \\cdot \\\\\nI2.2. & \\quad \\text{Assumptions} \\quad ::= \\text{Assumption Rest} \\cdot \\\\\nI3.1. & \\quad \\text{Assumption} \\quad ::= \\text{Type assignment} \\cdot \\\\\nI3.2. & \\quad \\text{Assumption} \\quad ::= \\text{Tvar} \\cdot \\\\\nI4.1. & \\quad \\text{Rest} \\quad ::= \\cdot \\\\\nI4.2. & \\quad \\text{Rest} \\quad ::= ; \\text{Assumption Rest} \\cdot \\\\\nI5.1. & \\quad \\text{Consequences} \\quad ::= \\text{Consequences} , \\text{Consequences} \\cdot \\\\\nI5.2. & \\quad \\text{Consequences} \\quad ::= \\text{Type assertion} \\cdot \\\\\nI5.3. & \\quad \\text{Consequences} \\quad ::= \\text{Texp} \\cdot \\\\\nI6. & \\quad \\text{Type assignment} \\quad ::= \\text{Var} : \\text{Texp} \\cdot \\\\\nI7. & \\quad \\text{Type assertion} \\quad ::= \\text{Exp} : \\text{Texp} \\cdot\n\\end{align*}\nCHAPTER 2\n\nFor instance, the typing \\( t;x:t \\rightarrow (\\text{inl } x \\mid t) : t+t \\) states that under the assumptions that (there exists a context in which) first of all a type \\( t \\) is introduced and secondly a variable \\( x \\) of type \\( t \\), one may assert that the expression \\( (\\text{inl } x \\mid t) \\) is of type \\( t+t \\). As usual we prefix a typing with the symbol \\( \\vdash \\) to indicate that it is derivable.\n\nLet \\( A \\in \\text{Assumptions} \\). The set \\( \\text{FTV}(A) \\) of free type variables of \\( A \\) is the set of type variables that occur as subassumptions in \\( A \\) (cf. I3.2). Hence for \\( x:t \\) an assumption \\( t \\notin \\text{FTV}(x:t) \\) !\n\nThe set \\( \\text{FV}(A) \\) of free variables of \\( A \\) is the set of variables that occur in any left-hand side of any type assignment in \\( A \\) (cf. I3.1 and I6).\n\nLet \\( C \\in \\text{Consequences} \\). The set \\( \\text{FTV}(C) \\) is the set of type variables occurring free in any expression or type expression contained in \\( C \\) (cf. I5.3 and I7). In particular \\( \\text{FTV}(e:te) = \\text{FTV}(e) \\cup \\text{FTV}(te) \\). Hence if \\( x:t \\) is a consequence then \\( t \\in \\text{FTV}(x:t) \\) (cf. above)! Similarly, \\( \\text{FV}(C) \\) is the set of free variables occurring in any expression contained in \\( C \\) (cf. I7). In particular \\( \\text{FV}(e:te) = \\text{FV}(e) \\).\n\nLet \\( A,A_1,A_2 \\in \\text{Assumptions} \\); \\( C_1,C_2 \\in \\text{Consequences} \\); \\( t \\in \\text{Tvar} \\); \\( tx,te,te_1,te_2 \\in \\text{Texp} \\); \\( x \\in \\text{Var} \\) and \\( e,e_1,e_2,f,f_1,f_2 \\in \\text{Exp} \\). Then the inference rules for type deduction are:\n\n<table>\n<thead>\n<tr>\n<th>Rule</th>\n<th>Premise</th>\n<th>Conclusion</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>TR1.</td>\n<td>( A \\vdash \\Omega )</td>\n<td>( A \\vdash t )</td>\n</tr>\n<tr>\n<td>TR2.</td>\n<td>( A; t; A_2 \\vdash t )</td>\n<td>( A \\vdash \\uparrow t )</td>\n</tr>\n<tr>\n<td>TR3.</td>\n<td>( A \\vdash te_1, te_2 )</td>\n<td>( A \\vdash te_1, te_2 )</td>\n</tr>\n<tr>\n<td>TR4.</td>\n<td>( A \\vdash te_1, te_2 )</td>\n<td>( A \\vdash te_1 + te_2 )</td>\n</tr>\n<tr>\n<td>TR5.</td>\n<td>( A \\vdash te_1, te_2 )</td>\n<td>( A \\vdash te_1 \\times te_2 )</td>\n</tr>\n<tr>\n<td>TR6.</td>\n<td>( A \\vdash te_1, te_2 )</td>\n<td>( A \\vdash te_1 \\rightarrow te_2 )</td>\n</tr>\n<tr>\n<td>TR7.</td>\n<td>( A; t \\vdash te )</td>\n<td>( A \\vdash v(A t \\mid te) )</td>\n</tr>\n<tr>\n<td>ER1.1</td>\n<td>( A \\vdash te )</td>\n<td>( A \\vdash (\\text{btm} \\mid te) : te )</td>\n</tr>\n</tbody>\n</table>\nER2. \\[ A_1 \\downarrow \\text{tx} \\quad \\text{provided } x \\in \\text{FV}(A_2) \\text{ and } \\text{FTV}(\\text{tx}) \\cap \\text{FTV}(A_2) = \\emptyset \\]\n\\[ A_1; x: \\text{tx}; A_2 \\downarrow x: \\text{tx} \\]\n\nER3.1.\n\\[ A \\downarrow e : \\uparrow \\text{te} \\]\n\nER3.2.\n\\[ A \\downarrow e : \\uparrow \\text{te} \\]\n\nER4.1.\n\\[ A \\downarrow e_1 : \\text{te}_1, \\text{te}_2 \\quad \\text{A} \\downarrow (\\text{inl } e_1 \\mid \\text{te}_2) : \\text{te}_1 + \\text{te}_2 \\]\n\\[ A \\downarrow (\\text{inls } e_1 \\mid \\text{te}_2) : \\text{te}_1 \\otimes \\text{te}_2 \\]\n\nER4.2.\n\\[ A \\downarrow \\text{te}_1, e_2 : \\text{te}_2 \\quad \\text{A} \\downarrow (\\text{inr } \\text{te}_1 \\mid e_2) : \\text{te}_1 + \\text{te}_2 \\]\n\\[ A \\downarrow (\\text{inrs } \\text{te}_1 \\mid e_2) : \\text{te}_1 \\otimes \\text{te}_2 \\]\n\nER4.3.1.\n\\[ A \\downarrow f_1 : \\text{te}_1 \\to \\text{te}, f_2 : \\text{te}_2 \\to \\text{te} \\quad \\text{A} \\downarrow (\\text{sum } f_1 f_2) : (\\text{te}_1 + \\text{te}_2) \\to \\text{te} \\]\n\nER4.3.2.\n\\[ A \\downarrow f_1 : \\text{te}_1 \\ominus \\text{te}, f_2 : \\text{te}_2 \\ominus \\text{te} \\quad \\text{A} \\downarrow (\\text{sums } f_1 f_2) : (\\text{te}_1 \\otimes \\text{te}_2) \\ominus \\text{te} \\]\n\nER5.1.\n\\[ A \\downarrow e : \\text{te}_1 \\times \\text{te}_2 \\quad \\text{A} \\downarrow (\\text{prol } e) : \\text{te}_1 \\]\n\\[ A \\downarrow (\\text{pror } e) : \\text{te}_2 \\]\n\nER5.2.\n\\[ A \\downarrow e : \\text{te}_1 \\otimes \\text{te}_2 \\quad \\text{A} \\downarrow (\\text{prols } e) : \\text{te}_1 \\]\n\\[ A \\downarrow (\\text{prors } e) : \\text{te}_2 \\]\n\nER5.3.\n\\[ A \\downarrow e_1 : \\text{te}_1, e_2 : \\text{te}_2 \\quad \\text{A} \\downarrow (\\text{prod } e_1 e_2) : \\text{te}_1 \\times \\text{te}_2 \\]\n\\[ A \\downarrow (\\text{prods } e_1 e_2) : \\text{te}_1 \\otimes \\text{te}_2 \\]\n\nER6.1.\n\\[ A; x: \\text{tx} \\downarrow e : \\text{te} \\quad \\text{A} \\downarrow (\\lambda x: \\text{tx} \\mid e) : \\text{tx} \\to \\text{te} \\]\n\\[ A \\downarrow (\\lambda s x: \\text{tx} \\mid e) : \\text{tx} \\ominus \\text{te} \\]\n\nER6.2.\n\\[ A \\downarrow f : \\text{te} \\to \\text{te}_1, e : \\text{te} \\quad \\text{A} \\downarrow (\\text{appl } f e) : \\text{te}_1 \\]\n\nER6.3.\n\\[ A \\downarrow f : \\text{te} \\ominus \\text{te}_1, e : \\text{te} \\quad \\text{A} \\downarrow (\\text{appls } f e) : \\text{te}_1 \\]\nCHAPTER 2\n\nER7.1. \\[ A \\vdash e : v(\\Lambda t \\mid te) \\]\n\\[ A \\vdash (\\text{intro } v(\\Lambda t \\mid te) \\mid e) : te^t_v(\\Lambda t \\mid te) \\]\n\nER7.2. \\[ A \\vdash e : te^t_v(\\Lambda t \\mid te), v(\\Lambda t \\mid te) \\]\n\\[ A \\vdash (\\text{elim } v(\\Lambda t \\mid te) \\mid e) : v(\\Lambda t \\mid te) \\]\n\nER8. \\[ A \\vdash t e 1 \\]\n\\[ A ; t \\vdash e : te \\]\n\\[ A \\vdash (\\Lambda t \\mid e)te 1 : te^t_{te 1} \\]\n\nER9. \\[ A \\vdash e : te 1, \\]\n\\[ A \\vdash e : te 2 \\]\n\\[ A \\vdash C_1 \\]\n\\[ A \\vdash C_2 \\]\n\\[ A \\vdash C_1, C_2 \\]\n\nprovided te 1 \\(\\equiv_\\alpha\\) te 2\n\nER10.1. \\[ A \\vdash C_1 \\]\n\\[ A \\vdash C_2 \\]\n\\[ A \\vdash C_1, C_2 \\]\n\nER10.2. \\[ A \\vdash C_1, C_2 \\]\n\\[ A \\vdash C_1 \\]\n\\[ A \\vdash C_2 \\]\n\nNotice that to each T- and E-rule of chapter 1 there corresponds exactly one inference rule. The additional rule ER9 signifies that we are only interested in type expressions up to \\(\\alpha\\)-conversion. The reason for this is that type expressions that are equal up to \\(\\alpha\\)-conversion denote the same domain. Rules ER10 are not essential. They merely allow us the notational convenience of typings containing more than one consequence. Therefore we shall leave applications of these rules implicit in the derivation of typings.\n\nMost proofs given below rely on the fact that given a typing we are able to determine the last inference rule of its derivation. In the absence of rule ER9 this last rule would be uniquely identifiable from the structure of the expression. Derivations of typings in which the expressions contain bound type variables, however, can always end with one or more applications of rule ER9. In order to avoid these trivial but cumbersome details we assume in all proofs, and without loss of generality, that no derivation ends with an application of rule ER9.\n2.3. Explicit typing.\n\nOur type inference system has been designed to ensure that under any given sequence of assumptions each expression has at most one type, which is, if it exists, derivable from the types of its constituting parts (Recall that a type is an equivalence class of type expressions under \\( \\alpha \\)-conversion.) In Reynolds[Re85] this property is called explicit typing.\n\nTheorem 2.3.1. [Explicit typing theorem]\n\nLet \\( A \\in \\text{Assumptions} \\); \\( t e_1, t e_2 \\in T_{\\exp} \\) and \\( e \\in \\exp \\). If both \\( \\vdash A \\rightarrow e : t e_1 \\) and \\( \\vdash A \\rightarrow e : t e_2 \\) then \\( t e_1 = \\alpha t e_2 \\).\n\nSketch of proof. By induction on the structure of expression \\( e \\). Note that to each of the rules E1.1 thru E8 to construct expressions there corresponds exactly one inference rule that enables us to assert a type for the expressions produced by that rule. Therefore the induction is straightforward.\n\n\\( \\Box \\)\n\nAs stated above it is necessary to provide expressions with a certain amount of type information to obtain an explicitly typed language. The need for additional type information in expressions produced by E4.1, E4.2 and E6.1 is rather obvious (see p.e. [Re85]). The reader may wonder, however, about the necessity of the type information contained in rules E7.1 and E7.2. Therefore let us assume, for the sake of the argument, that rule E7.2 is simplified to\n\n\\[\n\\text{Exp} ::= (\\text{elim Exp})\n\\]\n\nand that inference rule ER7.2 is accordingly modified to\n\n\\[\n\\frac{A \\rightarrow e : t e^{\\uparrow} \\nu(\\Lambda t | t e), \\nu(\\Lambda t | t e)}{A \\rightarrow (\\text{elim } e) : \\nu(\\Lambda t | t e)} \\tag{*}\n\\]\n\nLet \\( A \\in \\text{Assumptions} \\) be such that \\( \\vdash A \\rightarrow e : t e^{\\uparrow} \\nu(\\Lambda t | t), \\nu(\\Lambda t | t) \\). Then we may assert on\naccount of (*) that (elim | e) is of type v(Λ t|t). However, since \\( t^v_\\text{v}(\\Lambda t|t) \\equiv_\\text{x} \\text{v}(\\Lambda t|t) \\) we may apply rule ER9 before applying (*) and assert that (elim e) has type \\( \\text{v}(\\Lambda s|\\text{v}(\\Lambda t|t)) \\) as well. Therefore the type information \\( \\text{v}(\\Lambda \\text{tvar}|\\text{texp}) \\) is absolutely essential in rule E7.2 to obtain explicit typing. For reasons of symmetry the same type information has been added to rule E7.1, although one can show that explicit typing can be obtained without it.\n\nGiven an assumption A we define the set \\( \\text{WTV}(A) \\) (\\( \\text{WTE}(A) \\)) of well-typed variables (expressions) under A by\n\n\\[\n\\text{WTV}(A) = \\{ x \\in \\text{Var} \\mid (\\exists \\text{te} \\in \\text{Texp} \\mid \\vdash A \\triangleright x : \\text{te}) \\}\n\\]\n\n\\[\n\\text{WTE}(A) = \\{ e \\in \\text{Exp} \\mid (\\exists \\text{te} \\in \\text{Texp} \\mid \\vdash A \\triangleright e : \\text{te}) \\}\n\\]\n\nOn account of the explicit typing theorem one can also define for each assumption A a function \\( \\tau_A \\) that assigns to each expression \\( e \\in \\text{WTE}(A) \\) an arbitrary, but fixed, type expression \\( \\text{te} \\) such that \\( \\vdash A \\triangleright e : \\text{te} \\). We shall take care that whenever \\( \\tau_A \\) is used, the particular \\( \\text{te} \\) chosen for \\( \\tau_A(e) \\) is irrelevant, i.e. may be replaced by any type expression \\( \\text{te1} \\) such that \\( \\text{te1} \\equiv_\\text{x} \\text{te} \\).\n\n2.4. Elementary properties.\n\nBefore we state the fundamental properties of our type inference system, viz. inference rules for substitution and \\( \\alpha \\)-conversion, we first list some elementary properties of typings.\n\nProperty 2.4.1.[Introduction of type variables]\n\nFor \\( A \\in \\text{Assumptions} \\) and \\( \\text{te} \\in \\text{Texp} \\):\n\n\\( \\vdash A \\triangleright \\text{te} \\) iff \\( \\text{FTV(}\\text{te}) \\subseteq \\text{FTV}(A) \\)\n\n\\( \\Box \\)\n\nThis property expresses that all free type variables of a type expression should be properly introduced.\nProperty 2.4.2. [Additional inference rules]\n\nThe following additional inference rules are derivable from the ones given in section 2.2:\n\nRules to extend assumptions\n\nER11.1. \\[ \\frac{A \\rightarrow C}{\\text{provided } t \\in \\text{FTV}(C)} \\]\n\n\\[ \\frac{A; t \\rightarrow C}{A; x:tx \\rightarrow C} \\]\n\nRules to reorder assumptions\n\nER12.1. \\[ \\frac{A_1; s: t; A_2 \\rightarrow C}{A_1; t; s; A_2 \\rightarrow C} \\]\n\nER12.2. \\[ \\frac{A_1; x:tx; y:ty; A_2 \\rightarrow C}{\\text{provided } x \\neq y \\lor tx \\equiv \\alpha ty} \\]\n\n\\[ \\frac{A_1; y:ty; x:tx; A_2 \\rightarrow C}{A_1; y:ty; x:tx; A_2 \\rightarrow C} \\]\n\nER12.3. \\[ \\frac{A_1; x:tx; t; A_2 \\rightarrow C}{A_1; t; x:tx; A_2 \\rightarrow C} \\]\n\nER12.4. \\[ \\frac{A_1; t; x:tx; A_2 \\rightarrow C}{A_1; x:tx; t; A_2 \\rightarrow C} \\]\n\n\\[ \\frac{A_1; x:tx; t; A_2 \\rightarrow C}{\\text{provided } t \\in \\text{FTV}(tx)} \\]\n\n2.5. Substitution and $\\alpha$–conversion.\n\nAs indicated in chapter 1 three kinds of substitution can be performed. For each kind we present a corresponding inference rule. Likewise three kinds of $\\alpha$–conversion can be performed. Three additional inference rules state that each kind of $\\alpha$–conversion leaves the types of expressions invariant. In chapters 4 and 5 we shall demonstrate that $\\alpha$–conversion neither changes the meaning of type expressions nor the meaning of expressions.\nCHAPTER 2\n\nTheorem 2.5.1. [Substitution of type expressions for type variables in type expressions]\n\nLet $A_1, A_2 \\in \\text{Assumptions}$; $t \\in \\text{Tvar}$ and $t_1, t_{e1} \\in \\text{Texp}$. Then the following inference rule can be derived.\n\n\\[\n\\frac{A_1 \\vdash t \\in t_1}{A_1; t; A_2 \\vdash t_1}, \\quad \\text{provided } t \\notin \\text{FTV}(A_2)\n\\]\n\n\\[\nA_1; A_2 \\vdash t \\in t_{e1} \\quad \\Rightarrow \\quad t_1 \\vdash t_{e1}\n\\]\n\nProof. By induction on the structure of type expression $t_1$. All other cases being trivial we only consider the case $t_1 = v(A_2; u)$. Assume\n\n1. Let $t_1 = v(A_2; u)$\n\n2. $\\vdash A_1; t_1; A_2; s \\vdash tf$ \\hspace{1cm} (**),TR7\n\n3. Let $u$ be the first type variable such that $u \\notin t \\land u \\notin \\text{FTV}(tf) \\land u \\notin \\text{FTV}(t_1)$\n\n4. $\\vdash A_1; t_1; A_2; s; u \\vdash tf$ \\hspace{1cm} (2),(3),ER11.1\n\n5. $\\vdash A_1; t_1; A_2; s; u \\vdash u$ \\hspace{1cm} [TR2]\n\n6. $\\vdash A_1; t_1; A_2; s; u \\vdash tf$ \\hspace{1cm} (4),ER12.1\n\n7. $\\vdash A_1; t_1; A_2; s; u \\vdash tf$ \\hspace{1cm} (5),(6),IH\n\n8. $t \\notin \\text{FTV}(A_2; u) = \\text{FTV}(A_2) \\cup \\{u\\}$ \\hspace{1cm} (**),,(3)\n\n9. $\\vdash A_1; (A_2; u) t_1 \\vdash (t_1; u) t_1$ \\hspace{1cm} (*),(7),(8),IH\n\n10. $\\vdash A_1; A_2; t_1 \\vdash (t_1; u) t_1$ \\hspace{1cm} (3),(9)\n\n11. $\\vdash A_1; A_2; t_1 \\vdash v(A 2; u) (t_1; u) t_1$ \\hspace{1cm} (10),TR7\n\n12. $\\vdash A_1; A_2; t_1 \\vdash v(A 2; u) (t_1; u) t_1$ \\hspace{1cm} (3),(11),subst.\n\n13. $\\vdash A_1; A_2; t_1 \\vdash t_{e1}$ \\hspace{1cm} (1),(12)\n\n\\[\\square\\]\nTheorem 2.5.2. [Substitution of type expressions for type variables in expressions]\n\nLet $A_1, A_2 \\in \\text{Assumptions}$; $t \\in \\text{Tvar}$; $te, te_1 \\in \\text{Texp}$ and $e \\in \\text{Exp}$. Then the following inference rule can be derived\n\n\\[\n\\frac{\\Gamma \\vdash t \\vdash e : te}{\\Gamma \\vdash A_1 \\vdash A_2 \\vdash e : te}, \\quad \\text{provided } \\text{FTV}(A_1; t) \\cap \\text{FTV}(A_2) = \\emptyset\n\\]\n\nProof. By induction on the structure of expression $e$. We prove only a few cases. The remaining cases are trivial.\n\nAssume\n\n1. \\[\\Gamma \\vdash A_1 \\vdash te\\] \\hspace{1cm} (*)\n2. \\[\\Gamma \\vdash A_1, t; A_2 \\vdash e : te\\] \\hspace{1cm} (**) \\hspace{1cm} \\text{FTV}(A_1; t) \\cap \\text{FTV}(A_2) = \\emptyset \\hspace{1cm} (***)\n\n1.1. Let $e = x$ and $x \\notin \\text{FV}(A_2)$, hence $x \\notin \\text{FV}(A_1)$\n\n1.2. Let $A_3, A_4 \\in \\text{Assumptions}$ be such that\n\n a) $A_1 = A_3; x: te; A_4$\n b) $\\vdash A_3 \\vdash te$\n c) $x \\notin \\text{FV}(A_4; t; A_2)$\n d) $\\text{FTV}(te) \\cap \\text{FTV}(A_4; t; A_2) = \\emptyset$\n\n1.3. $x \\in \\text{FV}(A_4; A_{2te}) = \\text{FV}(A_4; t; A_2)$ \\hspace{1cm} [(**), ER2]\n\n1.4. $\\text{FTV}(te) \\cap \\text{FTV}(A_4; A_{2te}) = \\emptyset$ \\hspace{1cm} [(1.2c)]\n\n1.5. $\\vdash A_3; x; te; A_4; A_{2te} \\vdash x : te$ \\hspace{1cm} [(1.2a), (1.3), (1.4), ER2]\n\n1.6. $t \\in \\text{FTV}(te)$ \\hspace{1cm} [(1.2d)]\n\n1.7. $te = \\alpha te_1$ \\hspace{1cm} [(1.6)]\n\n1.8. $\\vdash A_1; A_{2te} \\vdash x : te$ \\hspace{1cm} [(1.2a), (1.5)]\n\n1.9. $\\vdash A_1; A_{2te} \\vdash x_{te_1} : te_{te_1}$ \\hspace{1cm} [(1.7), (1.8), ER9]\n\n1.10. $\\vdash A_1; A_{2te} \\vdash e_{te_1} : te_{te_1}$ \\hspace{1cm} [(1.1), (1.9)]\n2.1. Let \\( e = x \\) and \\( x \\in \\text{FV}(A_2) \\)\n\n2.2. Let \\( A_3, A_4 \\in \\text{Assumptions} \\) be such that \\[ (**), \\text{ER2} \\]\n a) \\( A_2 = A_3; x : t e ; A_4 \\)\n b) \\( \\vdash A_1; t; A_3 \\triangleright t e \\)\n c) \\( x \\notin \\text{FV}(A_4) \\)\n d) \\( \\text{FTV}(t e) \\cap \\text{FTV}(A_4) = \\emptyset \\)\n\n2.3. a) \\( t \\notin \\text{FTV}(A_3) \\)\n b) \\( t \\notin \\text{FTV}(A) \\)\n\n2.4. \\( \\vdash A_1; A_3^t_{te_1} \\triangleright t^e_{te_1} \\)\n\n2.5. \\( x \\in \\text{FV}(A_4^t_{te_1}) = \\text{FV}(A_4) \\)\n\n2.6. \\[\n\\text{FTV}(t^e_{te_1}) \\cap \\text{FTV}(A_4^t_{te_1}) \\\\\n= \\text{FTV}(t^e_{te_1}) \\cap \\text{FTV}(A_4) \\\\\n= ((\\text{FTV}(t e) \\setminus \\{t\\}) \\cup \\text{FTV}(t e_1)) \\cap \\text{FTV}(A_4) \\\\\n= \\text{FTV}(t e_1) \\cap \\text{FTV}(A_4) \\\\\n\\subseteq \\text{FTV}(A_4) \\cap \\text{FTV}(A_4) \\\\\n= \\emptyset \\]\n\n2.7. \\( \\vdash A_1; A_3^t_{te_1}; x : t e_{te_1}; A_4^t_{te_1} \\triangleright x : t e_{te_1} \\)\n\n2.8. \\( \\vdash A_1; A_2^t_{te_1} \\triangleright x^e_{te_1} : t e_{te_1} \\)\n\n2.9. \\( \\vdash A_1; A_2^t_{te_1} \\triangleright e^e_{te_1} : t e_{te_1} \\)\n\n3.1. Let \\( e \\equiv (\\lambda y : t e | f) \\)\n\n3.2. Let \\( t f \\in \\text{Texp} \\) be such that \\[ (**), \\text{ER6.1} \\]\n a) \\( \\vdash A_1; t; A_2 \\triangleright t y, t f \\)\n b) \\( \\vdash A_1; t; A_2; y : t y \\triangleright f : t f \\)\n c) \\( \\vdash t e \\equiv \\alpha t y \\rightarrow t f \\)\n\n3.3. \\( \\text{FTV}(A_1; t) \\cap \\text{FTV}(A_2; y : t y) = \\emptyset \\)\n\n3.4. \\( \\vdash A_1; (A_2; y : t y)^t_{te_1} \\triangleright f^t_{te_1} : t f^t_{te_1} \\)\n\n\\[ (**), \\text{ER2} \\]\n\n\\[ (**), \\text{ER6.1} \\]\n\n\\[ (**), \\text{ER2} \\]\n\n\\[ (**), \\text{ER6.1} \\]\n\n\\[ (**), \\text{ER2} \\]\n\n\\[ (**), \\text{ER6.1} \\]\n3.5. \\( \\vdash A_1; A_2 \\rightarrow t \\rightarrow t_{te1} \\rightarrow t_{te1} \\) \n\n3.6. \\( \\vdash A_1; A_2 \\rightarrow \\lambda y: t \\rightarrow t_{te1} \\rightarrow t_{te1} \\) \n\n3.7. \\( \\vdash A_1; A_2 \\rightarrow (\\lambda y: t \\rightarrow t_{te1} \\rightarrow t_{te1}) : t_{te1} \\rightarrow t_{te1} \\) \n\n3.8. \\( \\vdash A_1; A_2 \\rightarrow e_{te1} : t_{te1} \\) \n\n4.1. Let \\( e = (\\text{elim} v(\\Lambda s | t f) | f) \\) \n\n4.2. \\( \\vdash A_1; A_2 \\rightarrow f : t f \\rightarrow v(\\Lambda s | t f), v(\\Lambda s | t f) \\) \n\n4.3. \\( \\vdash A_1; A_2 \\rightarrow f_{te1} : t f_{te1} \\rightarrow t f_{te1} \\) \n\n4.4. Let \\( r \\) be the first type variable such that \\( r \\neq t \\land r \\notin FTV(tf) \\land r \\notin FTV(te1) \\) \n\n4.5. \\( v(\\Lambda s | t f)_{te1} = v(\\Lambda r | t rf)_{te1} \\) \n\n4.6. \\( (t f \\rightarrow v(\\Lambda s | t f)_{te1})_{te1} \\) \n\n4.7. \\( \\vdash A_1; A_2 \\rightarrow f_{te1} : ((t f)_{te1} \\rightarrow v(\\Lambda r | t rf)_{te1}) \\) \n\n4.8. \\( \\vdash A_1; A_2 \\rightarrow v(\\Lambda s | t f)_{te1} \\) \n\n4.9. \\( \\vdash A_1; A_2 \\rightarrow v(\\Lambda r | t rf)_{te1} \\) \n\n4.10. \\( \\vdash A_1; A_2 \\rightarrow (\\text{elim} v(\\Lambda r | (t f)_{te1}) | f_{te1}) : v(\\Lambda r | (t f)_{te1}) \\) \n\n4.11. \\( \\vdash A_1; A_2 \\rightarrow (\\text{elim} v(\\Lambda s | t f) | f_{te1}) : v(\\Lambda s | t f)_{te1} \\) \n\n4.12. \\( \\vdash A_1; A_2 \\rightarrow e_{te1} : t e_{te1} \\) \n\n4.13. \\( \\vdash A_1; A_2 \\rightarrow e_{te1} : t e_{te1} \\) \n\n5.1. Let \\( e = (\\Lambda s | f) tf \\) \n\n5.2. \\( \\vdash A_1; A_2 \\rightarrow tf \\) \n\n5.3. Let \\( tf \\in Texp \\) be such that \n\na) \\( \\vdash A_1; A_2; s \\rightarrow f: tf \\) \n\nb) \\( te = \\alpha t f_{te1} \\)\nCHAPTER 2\n\n5.4. Let \\( r \\) be the first type variable such that\n\na) \\( r \\notin \\text{FTV}(f:tf) \\)\n\nb) \\( r \\notin t \\land r \\notin \\text{FTV}(te_1) \\)\n\n5.5. \\( \\vdash A_1;A_2;s:r \\rightarrow f:tf \\) \\([5.3a),(5.4a),ER11.1]\\)\n\n5.6. \\( \\vdash A_1;A_2;r;s \\rightarrow f:tf \\) \\([5.5),ER12.1] \\)\n\n5.7. \\( \\vdash A_1;A_2;r \\rightarrow r \\) \\([TR2]\\)\n\n5.8. \\( \\vdash A_1;A_2;r \\rightarrow t^s_r : t^s_r \\) \\([5.6),(5.7),IH]\\)\n\n5.9. \\( t \\notin \\text{FTV}(A_2;r) \\) \\([(*),(5.4b)]\\)\n\n5.10. \\( \\vdash A_1;(A_2;r)_t^{te_1} \\rightarrow (t^s_r)^{te_1} : tf^s_r^{te_1} \\) \\([(*),(5.8),(5.9),IH]\\)\n\n5.11. \\( \\vdash A_1:A_2^t;A_1^t ; r \\rightarrow t^r_r^{te_1} : tr^s_r^{te_1} \\) \\([5.10]\\)\n\n5.12. \\( \\vdash A_1:A_2^t;A_1^t ; tf^r_r^{te_1} \\) \\([(*),(5.2),(*),thm2.5.1]\\)\n\n5.13. \\( \\vdash A_1:A_2^t;A_1^t ; (A_1 r | t^s_r^{te_1}): (t^s_r^{te_1})^{te_1} : tf^s_r^{te_1} \\) \\([5.11),(5.12),E8]\\)\n\n5.14. \\( (t^s_r^{te_1})^{te_1} : tf^s_r^{te_1} \\)\n\n5.15. \\( \\vdash A_1:A_2^t;A_1^t ; (A_1 r | t^s_r^{te_1})^{te_1} : te^r_r^{te_1} \\) \\([5.13),(5.14),ER9]\\)\n\n5.16. \\( \\vdash A_1:A_2^t;A_1^t ; e^t_r^{te_1} : te^r_r^{te_1} \\) \\([5.1),(5.15)]\\)\n\n\\( \\square \\)\n\n**Theorem 2.5.3.**[renaming bound type variables]\n\nLet \\( A \\in \\text{Assumptions} ; s,t \\in Tvar ; te,te_1,te_2 \\in Texp \\) and \\( e \\in \\text{Exp} \\). Then the following inference rules can be derived:\n\n**ER15.1.**\n\n\\[\nA \\rightarrow v(\\Lambda r t | te) , \\\\\nA \\rightarrow v(\\Lambda r s | te^f_s) \\\\\n\\]\n\nprovided \\( s \\notin \\text{FTV}(te) \\)\n\n**ER15.2.**\n\n\\[\nA \\rightarrow (\\Lambda s | e^t_s | te_1) : te_2 \\\\\nA \\rightarrow (\\Lambda s | e^t_s)te_1 : te_2 \\\\\n\\]\n\nprovided \\( s \\notin \\text{FTV}(e_1 ^\\tau_A,t(e)) \\)\n\n18\nProof.\n\nAssume \\( s \\in \\text{FTV}(\\text{te}) \\)\n\n\\[ \\vdash A \\triangleright \\nu(A \\ t | \\text{te}) \\] \n\\[ (*) \\]\n\\[ (**) \\]\n\n1. \\[ \\vdash A; t \\triangleright \\text{te} \\] \n\\[ ([**),TR7] \\]\n2. \\[ \\vdash A; t; s \\triangleright \\text{te} \\] \n\\[ ([*),(1),ER11.1] \\]\n3. \\[ \\vdash A; s; t \\triangleright \\text{te} \\] \n\\[ [(2),ER12.1] \\]\n4. \\[ \\vdash A; s \\triangleright s \\] \n\\[ [TR2] \\]\n5. \\[ \\vdash A; s \\triangleright \\text{te}_s^t \\] \n\\[ [(3),(4),thm2.5.1] \\]\n6. \\[ \\vdash A \\triangleright \\nu(A s | \\text{te}_s^t) \\] \n\\[ [(5),TR7] \\]\n\nHence rule \\( \\text{ER15.1} \\) is derivable.\n\nAssume \\( s \\in \\text{FTV}(\\text{te}:\\text{te}) \\)\n\n\\[ \\vdash A \\triangleright (A \\ t | e)\\text{te} \\ _1 : \\text{te} \\ _2 \\] \n\\[ (*) \\]\n\\[ (**) \\]\n\n1. \\[ \\vdash A \\triangleright \\text{te} \\ _1 \\] \n\\[ ([**),ER8] \\]\n2. Let \\( \\text{te} \\in \\text{Texp} \\) be such that\n\na) \\[ \\vdash A; t \\triangleright e : \\text{te} \\] \n\\[ ([*),(2a),ER11.1] \\]\n\nb) \\[ \\text{te} \\ _2 = \\alpha \\text{te} \\ _1^t \\] \n\\[ [(2b),(3),ER12.1] \\]\n3. \\[ \\vdash A; t; s \\triangleright e : \\text{te} \\] \n\\[ [(3),ER12.1] \\]\n4. \\[ \\vdash A; s; t \\triangleright e : \\text{te} \\] \n\\[ [TR2] \\]\n5. \\[ \\vdash A; s \\triangleright s \\] \n\\[ [(4),(5),thm2.5.2] \\]\n6. \\[ \\vdash A; s \\triangleright e_s^t : \\text{te}_s^t \\] \n\\[ [(1),(6),ER8] \\]\n7. \\[ \\vdash A \\triangleright (A s | e_s^t)\\text{te} \\ _1 : (\\text{te}_s^t)\\text{te} \\ _1 \\] \n\\[ [(7),ER9,subst] \\]\n8. \\[ \\vdash A \\triangleright (A s | e_s^t)\\text{te} \\ _1 : \\text{te} \\ _1^t \\] \n\\[ [(2b),(8),ER9] \\]\n9. \\[ \\vdash A \\triangleright (A s | e_s^t)\\text{te} \\ _1 : \\text{te} \\ _2 \\]\n\nHence rule \\( \\text{ER15.2} \\) is derivable.\n\n\\( \\square \\)\nCHAPTER 2\n\nTheorem 2.5A. [Substitution of expressions for variables in expressions]\n\nLet \\( A \\in \\text{Assumptions} ; \\, t_e, t_{e1} \\in \\text{Texp} ; \\, x \\in \\text{Var} \\) and \\( e, e_1 \\in \\text{Exp} \\). Then the following inference rule is derivable:\n\n\\[\n\\begin{align*}\nA \\Rightarrow e_1 : t_e \\\\\nA ; x : t_{e1} \\Rightarrow e : t_e \\\\\n\\hline\nA \\Rightarrow e_{e_1}^x : t_e\n\\end{align*}\n\\]\n\nProof. By induction on the structure of expression \\( e \\). We consider only a few cases. The other cases are trivial.\n\nAssume \\( \\vdash A \\Rightarrow e_1 : t_e \\) \\hspace{1cm} (*)\n\n\\( \\vdash A ; x : t_{e1} \\Rightarrow e : t_e \\) \\hspace{1cm} (**) \n\n1.1. Let \\( e = x \\)\n\n1.2. \\( \\vdash A \\Rightarrow t_e \\) \\hspace{1cm} (**) \n\n1.3. \\( \\vdash A ; x : t_{e1} \\Rightarrow e : t_e \\) \\hspace{1cm} [(1.1),(1.2),ER2]\n\n1.4. \\( t_e = a \\) \\hspace{1cm} [(*), subst] \n\n1.5. \\( \\vdash A \\Rightarrow x_{e_1}^x : t_e \\) \\hspace{1cm} [(**),(1.3),thm2.3.1] \n\n1.6. \\( \\vdash A \\Rightarrow x_{e_1}^x : t_e \\) \\hspace{1cm} [(1.4),(1.5),ER9] \n\n1.7. \\( \\vdash A \\Rightarrow e_{e_1}^x : t_e \\) \\hspace{1cm} [(1.1),(1.6)] \n\n2.1. Let \\( e = y \\wedge y \\neq x \\)\n\n2.2. Let \\( A_1, A_2 \\in \\text{Assumptions} \\) be such that \\( [(2.1),(**),ER2] \\)\n\na) \\( A = A_1 ; y : t_e ; A_2 \\)\n\nb) \\( \\vdash A_1 \\Rightarrow t_e \\)\n\nc) \\( y \\notin \\text{FV}(A_2 ; x : t_{e1}) \\)\n\nd) \\( \\text{FTV}(t_e) \\cap \\text{FTV}(A_2 ; x : t_{e1}) = \\emptyset \\)\n\n2.3. \\hspace{1cm} [(2.1),(2.2c)]\n\na) \\( y \\notin \\text{FV}(A_2) \\)\n\nb) \\( \\text{FTV}(t_e) \\cap \\text{FTV}(A_2) = \\emptyset \\) \\hspace{1cm} [(2.2d)]\n\n2.4. \\( \\vdash A \\Rightarrow y : t_e \\) \\hspace{1cm} [(2.2a),(2.3),ER2]\n2.5. \\[ \\vdash A \\rightarrow y^x_{e1} : te \\] \\[[2.1),(2.4)]\n\n2.6. \\[ \\vdash A \\rightarrow e^x_{e1} : te \\] \\[[2.1),(2.4)]\n\n3.1. Let \\( e \\equiv (\\lambda y:te2 \\mid f) \\)\n\n3.2. Let \\( tf \\in Texp \\) be such that\n\\( a) \\vdash A;x:te1 \\rightarrow te2 , tf \\)\n\\( b) \\vdash A;x:te1;y:te2 \\rightarrow f : tf \\)\n\\( c) te \\equiv \\alpha te2 \\rightarrow tf \\)\n\n3.3. Let \\( z \\) be the first variable such that\n\\( z \\notin x \\land z \\notin \\text{FV}(f) \\land z \\notin \\text{FV}(e1) \\)\n\n3.4. \\[ \\vdash A;x:te1;y:te2 \\rightarrow te2 \\] \\[[3.2a),ER11.2]\n\n3.5. \\[ \\vdash A;x:te1;y:te2;z:te2 \\rightarrow f : tf \\] \\[[3.2b),(3.4),(3.3),ER11.2]\n\n3.6. \\[ \\vdash A;z:te2;x:te1;y:te2 \\rightarrow f : tf \\] \\[[3.5),ER12.2]\n\n3.7. \\[ \\vdash A;x:te1;z:te2 \\rightarrow z : te2 \\] \\[[3.2a),ER2]\n\n3.8. \\[ \\vdash A;z:te2;x:te1 \\rightarrow z : te2 \\] \\[[3.3),(3.7),ER12.2]\n\n3.9. \\[ \\vdash A;z:te2;x:te1 \\rightarrow f^y_z : tf \\] \\[[3.6),(3.8),IH]\n\n3.10. \\[ \\vdash A \\rightarrow te2 , tf \\] \\[[3.2a]]\n\n3.11. \\[ \\vdash A;z:te2 \\rightarrow e1 : te1 \\] \\[[(*),(3.10),(3.3),ER11.2]\n\n3.12. \\[ \\vdash A;z:te2 \\rightarrow (f^y_z)^{x}_{e1} : tf \\] \\[[3.9),(3.11),IH]\n\n3.13. \\[ \\vdash A \\rightarrow (\\lambda z:te2 \\mid (f^y_z)^{x}_{e1}) : te2 \\rightarrow tf \\] \\[[3.10),(3.12),ER6.1]\n\n3.14. \\[ \\vdash A \\rightarrow (\\lambda y:te2 \\mid f)^{x}_{e1} : te2 \\rightarrow tf \\] \\[[3.3),(3.13)]\n\n3.15. \\[ \\vdash A \\rightarrow e^x_{e1} : te \\] \\[[3.1),(3.2c)(3.14),ER9]\n\n4.1. Let \\( e \\equiv (\\Lambda s \\mid f)tf1 \\)\n\n4.2. \\[ \\vdash A;x:te1 \\rightarrow tf1 \\] \\[[**),ER8]\n\n4.3. Let \\( tf \\in Texp \\) be such that\n\\( a) \\vdash A;x:te1;s \\rightarrow f : tf \\)\n\\( b) te \\equiv \\alpha tf^s_{tf1} \\)\nCHAPTER 2\n\n4.4. Assume without loss of generality that\n\\[ s \\notin \\text{FTV}(e_1;te_1) \\]\n\n4.5. \\[ \\vdash A;s \\triangleright e_1 : te_1 \\] [\\((*)\\),(4.4),ER11.1]\n\n4.6. \\[ \\vdash A;s;x:te_1 \\triangleright f : tf \\] [\\((4.3a)\\),ER12.3]\n\n4.7. \\[ \\vdash A;s \\triangleright f^x_{e_1} : tf \\] [\\((4.5),(4.6),\\text{IH}\\)]\n\n4.8. \\[ \\vdash A \\triangleright tf_1 \\] [\\((4.2)\\)]\n\n4.9. \\[ \\vdash A \\triangleright (\\Lambda s \\mid f^x_{e_1})tf_1 : tf^s_{tf_1} \\] [\\((4.7),(4.8),\\text{ER8}\\)]\n\n4.10. \\[ \\vdash A \\triangleright e^x_{e_1} : te \\] [\\((4.1),(4.3b),(4.9),\\text{ER9}\\)]\n\n\\[ \\Box \\]\n\nTheorem 2.5.5.[renaming bound variables]\n\nLet \\( A \\in \\text{Assumptions} \\); \\( te_1,te_2 \\in \\text{Texp} \\); \\( x,y \\in \\text{Var} \\) and \\( e \\in \\text{Exp} \\). Then the following inference rules can be derived:\n\n**ER17.1.**\n\n\\[\n\\frac{ A \\triangleright (\\lambda x:te_1 \\mid e) : te_2 }{ A \\triangleright (\\lambda y:te_1 \\mid e^x_{y}) : te_2 }, \\]\n\nprovided \\( y \\notin \\text{FV}(e) \\)\n\n**ER17.2.**\n\n\\[\n\\frac{ A \\triangleright (\\lambda s x:te_1 \\mid e) : te_2 }{ A \\triangleright (\\lambda s y:te_1 \\mid e^x_{y}) : te_2 }, \\]\n\nprovided \\( y \\notin \\text{FV}(e) \\)\n\n**Proof.**\n\nAssume \\( y \\notin \\text{FV}(e) \\) \\((*)\\)\n\n\\[ \\vdash A \\triangleright (\\lambda x:te_1 \\mid e) : te_2 \\] \\((***)\\)\n\n1. Let \\( te \\in \\text{Texp} \\) be such that \\([(***)],\\text{ER6.1}\\)\n a) \\[ \\vdash A \\triangleright te_1 , te \\]\n b) \\[ \\vdash A;x:te_1 \\triangleright e : te \\]\n c) \\( te_2 =^\\alpha te_1 \\rightarrow te \\)\n\n2. \\[ \\vdash A;x:te_1 \\triangleright te_1 \\] \\([(1a),\\text{ER11.2}]\\)\n\n3. \\[ \\vdash A;y:te_1 \\triangleright y : te_1 \\] \\([(1a),\\text{ER2}]\\)\n\n22\nHence rule ER17.1 is derivable. Similarly it can be shown that rule ER17.2 is derivable.\n\n□\nCHAPTER 3\n\n3. REDUCTION\n\n3.1. Introduction.\n\nIn this chapter a reduction relation \\( \\Rightarrow \\) on expressions is defined that provides an operational semantics for our kernel language. We shall present this reduction relation in the form of a formal theory (cf. Hindley and Seldin [HiSe86]). Besides reduction rules that deal with expressions having function types, which are familiar from the lambda calculus, the theory contains reduction rules for expressions having sum, product or recursive types.\n\nIn order to present this theory we need the notion of a context. Suppose we take an expression and replace some of its subexpressions by the fresh symbol \\( \\$ \\). The resulting term is called a context. Actually we think of a context as an expression with some holes in it. The symbol \\( \\$ \\) merely enables us to give a proper syntactic definition. To that end replace in rules E1 – E8 of chapter 1 the nonterminal \\( \\text{Exp} \\) by \\( \\text{C\\_and\\_E} \\) and add the rule \\( \\text{C\\_and\\_E} ::= \\$ \\). Let \\( \\text{Exp} \\) be the subset of sentences of \\( \\text{C\\_and\\_E} \\) that contain zero occurrences of the symbol \\( \\$ \\), and let \\( \\text{Context} \\) be the subset of sentences that contain at least one occurrence of \\( \\$ \\). Notice that substituting an expression for \\( \\$ \\) describes the process of filling in the holes of a context.\n\n3.2. The theory of reduction.\n\nThe theory of reduction consists of formula's of the form \\( \\text{Exp} \\Rightarrow \\text{Exp} \\) and the following rules:\n\n\\[\n\\begin{align*}\n(\\sigma_1) & \\quad \\text{appl} \\ (\\text{sum} \\ f_1 \\ f_2) \\ (\\text{inl} \\ e_1 \\ | \\ te2)) \\Rightarrow \\ (\\text{appl} \\ f_1 \\ e_1) \\\\\n(\\sigma_2) & \\quad \\text{appl} \\ (\\text{sum} \\ f_1 \\ f_2) \\ (\\text{inr} \\ te1 \\ | \\ e2)) \\Rightarrow \\ (\\text{appl} \\ f_2 \\ e_2) \\\\\n(\\sigma_3) & \\quad \\text{appl} \\ (\\text{sums} \\ f_1 \\ f_2) \\ (\\text{inls} \\ e_1 \\ | \\ te2)) \\Rightarrow \\ (\\text{appl} \\ f_1 \\ e_1) \\\\\n(\\sigma_4) & \\quad \\text{appl} \\ (\\text{sums} \\ f_1 \\ f_2) \\ (\\text{inrs} \\ te1 \\ | \\ e2)) \\Rightarrow \\ (\\text{appl} \\ f_2 \\ e_2)\n\\end{align*}\n\\]\n\\((\\sigma_3)\\) \\((\\text{sums } (\\lambda s \\, x: t e_1 \\mid (\\text{apps } f \\, (\\text{inls } x \\mid t e_2))) \\hfill x \\in \\text{FV}(f)\\)\n\n\\((\\lambda s \\, x: t e_2 \\mid (\\text{apps } f \\, (\\text{inrs } t e_1 \\mid x))) \\hfill x \\in \\text{FV}(f)\\)\n\n\\((\\pi_1)\\) \\((\\text{prol } (\\text{prod } e_1 \\, e_2)) \\hfill e_1\\)\n\n\\((\\pi_2)\\) \\((\\text{pror } (\\text{prod } e_1 \\, e_2)) \\hfill e_2\\)\n\n\\((\\pi_3)\\) \\((\\text{prod } (\\text{prol } e) \\, (\\text{pror } e)) \\hfill e\\)\n\n\\((\\pi_4)\\) \\((\\text{prols } (\\text{prods } e_1 \\, e_2)) \\hfill e_1\\), \\hspace{1cm} \\text{provided } e_2 \\text{ in normal form}\n\n\\((\\pi_5)\\) \\((\\text{prors } (\\text{prods } e_1 \\, e_2)) \\hfill e_2\\), \\hspace{1cm} \\text{provided } e_1 \\text{ in normal form}\n\n\\((\\pi_6)\\) \\((\\text{prods } (\\text{prols } e) \\, (\\text{prors } e)) \\hfill e\\)\n\n\\((\\varepsilon_1)\\) \\((\\text{elim } v(\\lambda t \\, t e) \\mid (\\text{intro } v(\\lambda t \\, t e) \\mid e)) \\hfill e\\)\n\n\\((\\varepsilon_2)\\) \\((\\text{intro } v(\\lambda t \\, t e) \\mid (\\text{elim } v(\\lambda t \\, t e) \\mid e)) \\hfill e\\)\n\n\\((\\beta_1)\\) \\((\\text{appl } (\\lambda x: t x \\mid e) \\, e_1) \\hfill e^x_{e_1}\\)\n\n\\((\\beta_2)\\) \\((\\text{apps } (\\lambda s \\, x: t x \\mid e) \\, e_1) \\hfill e^x_{e_1}\\), \\hspace{1cm} \\text{provided } e_1 \\text{ in normal form}\n\n\\((\\beta_3)\\) \\((\\lambda t \\mid e) t e_1 \\hfill e^t_{t e_1}\\)\n\n\\((\\eta_1)\\) \\((\\lambda x: t x \\mid (\\text{appl } f \\, x)) \\hfill f\\), \\hspace{1cm} x \\in \\text{FV}(f)\n\n\\((\\eta_2)\\) \\((\\lambda s \\, x: t x \\mid (\\text{apps } f \\, x)) \\hfill f\\), \\hspace{1cm} x \\in \\text{FV}(f)\n\n\\((\\rho)\\) \\(e \\hfill e\\)\n\n\\(\\text{reflexivity}\\)\n\n\\(e_1 \\hfill e_2\\)\n\n\\(e_2 \\hfill e_3\\)\n\n\\(e_1 \\hfill e_3\\)\n\n\\(\\tau\\)\n\n\\(\\text{transitivity}\\)\n\n\\(\\psi\\)\n\n\\[\\frac{e_1 \\rightarrow e_2}{c^e_{e_1} \\rightarrow c^e_{e_2}}\\]\n\nRule \\(\\psi\\) expresses the substitutivity property (or compatibility property as it is called in Barendregt [Ba81]) of \\(\\rightarrow\\). It states, however, one exception, viz. subexpressions appearing in an up-context cannot be reduced. Hence \\(\\rightarrow\\) is the reflexive, transitive and (almost) substitutive closure of the one-step reduction relation defined by rules \\(\\nu\\) thru \\(\\eta\\). The left-hand side of any of these rules is called a redex. An expression in which all redices, if any, appear inside an up-context is called a normal form.\nCHAPTER 3\n\nNotice that the notions redex and normal form are actually defined by mutual recursion, on account of the constraints in rules $\\pi_4$, $\\pi_5$ and $\\beta_2$. In particular $(\\text{btm} \\mid \\text{te})$ is not a normal form. This is proper, since it corresponds to a nonterminating computation that yields no information at all. On the other hand, any up-expression is in normal form.\n\nUp-expressions can be used to enforce lazy evaluation. Consider the two expressions\n\n$$(\\text{appl} \\ (\\lambda \\ x : \\text{tx} \\mid (\\text{inl} \\ x \\mid \\text{te2})) \\ e)$$\n\nand\n\n$$(\\text{appl} \\ (\\lambda \\ x : \\uparrow \\text{tx} \\mid (\\text{inl} \\ (\\text{down} \\ x) \\mid \\text{te2})) \\ (\\text{up} \\ e))$$\n\nIf $e \\to e_1$ then $(\\text{appl} \\ (\\lambda \\ x : \\text{tx} \\mid (\\text{inl} \\ x \\mid \\text{te2})) \\ e) \\to (\\text{inl} \\ e_1 \\mid \\text{te2})$ in two distinct ways, viz. applying rule $\\beta_1$ before rule $\\psi$, which is called lazy evaluation or applying rule $\\psi$ and then rule $\\beta_1$, which is called eager evaluation. Likewise $(\\text{appl} \\ (\\lambda \\ x : \\uparrow \\text{tx} \\mid (\\text{inl} \\ (\\text{down} \\ x) \\mid \\text{te2})) \\ (\\text{up} \\ e)) \\to (\\text{inl} \\ e_1 \\mid \\text{te2})$, but the order in which the rules are applied has to be first $\\beta_1$ then $\\delta$ and finally $\\psi$.\n\nOne would expect that reduction does not change the type of an expression. This is indeed the case, if renaming of bound variables is ignored. Of course type expressions that differ only in the names of their bound variables have the same semantics. Hence, if we are a little more liberal and consider a type to be a class of type expressions that are equal up to $\\alpha$-conversion then we can say that types are invariant under reduction.\n\n**Theorem 3.2.1.**\n\nLet $A \\in \\text{Assumptions}$ and $e_1, e_2 \\in \\text{Exp}$.\n\nIf $e_1 \\in \\text{WTE}(A)$ and $e_1 \\to e_2$\n\nThen $e_2 \\in \\text{WTE}(A)$ and $\\tau_A(e_1) =_\\alpha \\tau_A(e_2)$. \n\n26\nProof. With the exception of the $\\beta$-rules this follows for each of the remaining rules $\\nu$ thru $\\eta$ by a straightforward calculation. Rules $\\beta_1$ and $\\beta_2$ preserve types on account of theorem 2.5.3. Rule $\\beta_3$ preserves types on account of theorem 2.5.4.\n\n\\[\\square\\]\n\nRemark. For reductions $e_1 \\rightarrow e_2$ that do not comprise rule $\\beta_3$ one can prove that $\\tau_A(e_1) \\equiv \\tau_A(e_2)$.\n\n\\[\\square\\]\nCHAPTER 4\n\n4. SEMANTICS OF TYPE EXPRESSIONS\n\n4.1. Introduction.\n\nIn this chapter we show how a complete partial order (c.p.o.) can be associated to every type expression. The c.p.o.'s corresponding to recursively defined types, i.e. type expressions of the form $\\nu(A \\, t \\mid te)$, are found using the inverse limit construction. The use of this technique to solve recursive domain equations has been described by Smyth & Plotkin [SP82], Lehmann & Smyth [LS81] and others. A detailed description (for the case of the category of c.p.o.'s with embedding–projection pairs as morphisms) can be found in Bos & Hemerik [BH88]. For general aspects of category theory we refer to Herrlich & Strecker [HeStr73] or Maclane [McL71].\n\nIn this section we introduce some notations and conventions. Some elementary properties of the concepts introduced in this section are given in section 4.2. The actual semantics of type expressions is given in section 4.3. We first associate a certain functor with every type expression. The c.p.o. corresponding to a type expression is then found by applying that functor to an object, called the type environment. Finally in section 4.4. some elementary properties of the semantics of type expressions are given.\n\nLet $s, t \\in \\text{Tvar}$. In the sequel we shall use the following notations.\n\n- $\\mathcal{C} = \\mathsf{CPO}_{\\text{PR}}$, the category of c.p.o.'s with embedding/projection pairs as morphisms\n- $\\Pi \\mathcal{C} = \\prod_{t \\in \\text{Tvar}} \\mathsf{CPO}_{\\text{PR}}$\n- $P_t : \\Pi \\mathcal{C} \\rightarrow \\mathcal{C}$, the projection functor on component $t$.\n- If $A \\in \\text{obj}(\\Pi \\mathcal{C})$, then $A_t = P_t(A)$.\n- If $f \\in \\text{mor}(\\Pi \\mathcal{C})$, then $f_t = P_t(f)$.\n- If $A \\in \\text{obj}(\\Pi \\mathcal{C})$, $B \\in \\text{obj}(\\mathcal{C})$, then $A[B/t] \\in \\text{obj}(\\Pi \\mathcal{C})$ is defined by\n\\[ A_{[B/t]}_s = \\begin{cases} A & \\text{if } s \\neq t \\\\ B & \\text{if } s = t \\end{cases} \\]\n\nIf \\( f \\in \\text{mor}(\\Pi C) \\), \\( g \\in \\text{mor}(C) \\), then \\( f[g/t] \\in \\text{mor}(\\Pi C) \\) is defined by\n\n\\[ f[g/t]_s = \\begin{cases} f & \\text{if } s \\neq t \\\\ g & \\text{if } s = t \\end{cases} . \\]\n\nConsider the functors \\( F : \\Pi C \\to \\Pi C \\) and \\( G : \\Pi C \\to C \\). Then the functor\n\n\\( F[G/t] : \\Pi C \\to \\Pi C \\) is defined by\n\n\\[ P_s \\circ F[G/t] = \\begin{cases} P_s \\circ F & \\text{if } s \\neq t \\\\ G & \\text{if } s = t \\end{cases} . \\]\n\n- \\( \\text{Id} : \\Pi C \\to \\Pi C \\), the identity functor.\n\n- \\( \\text{id}_A : A \\to A \\), the identity morphism on object \\( A \\).\n\n- Consider the functor \\( F : \\Pi C \\to C \\). The functor \\( \\text{abstr}_F : \\Pi C \\to (C \\to C) \\) is defined in the following way:\n\n i) For \\( A \\in \\text{obj}(\\Pi C) \\) is \\( \\text{abstr}_F(A) \\) the object in the category \\( C \\to C \\) (i.e. the functor \\( C \\to C \\)) defined by\n\n \\[ \\text{abstr}_F(A)(B) = F(A[B/t]) \\text{ for } b \\in \\text{obj}(C) , \\]\n\n \\[ \\text{abstr}_F(A)(g) = F(\\text{id}_A[g/t]) \\text{ for } g \\in \\text{mor}(C) . \\]\n\n ii) For \\( f \\in \\text{mor}(\\Pi C) \\) is \\( \\text{abstr}_F(f) \\) the morphism in the category \\( C \\to C \\) (i.e. the natural transformation) defined by\n\n \\[ (\\text{abstr}_F(f))_B = F(f[\\text{id}_B/t]) \\text{ for } B \\in \\text{obj}(C) \\]\n\nSuppose \\( D \\) is an arbitrary category. A functor \\( F : \\Pi C \\to D \\) will be called independent of \\( t \\) if\n\n\\( F = F \\circ \\text{Id}[G/t] \\) for all functors \\( G : \\Pi C \\to C \\).\n\nWe shall use the following functors.\nCHAPTER 4\n\n\\[ \\text{CONST}_A : \\Pi C \\rightarrow C , \\text{the constant functor corresponding to an object } A \\in \\text{obj}(C) , \\]\n\\[ \\text{LIFT} : C \\rightarrow C , \\text{the lifting functor}, \\]\n\\[ \\text{DS} : C \\times C \\rightarrow C , \\text{the disjoint sum functor}, \\]\n\\[ \\text{CP} : C \\times C \\rightarrow C , \\text{the cartesian product functor}, \\]\n\\[ \\text{FS} : C \\times C \\rightarrow C , \\text{the function space functor}, \\]\n\\[ \\text{CS} : C \\times C \\rightarrow C , \\text{the coalesced sum functor}, \\]\n\\[ \\text{SP} : C \\times C \\rightarrow C , \\text{the smash product functor}, \\]\n\\[ \\text{SF} : C \\times C \\rightarrow C , \\text{the strict function space functor}, \\]\n\\[ \\text{IFP} : [C \\rightarrow C] \\rightarrow C , \\text{the initial fixed point functor}. \\]\n\nThe formal definition of these functors can be found in Bos & Hemerik [BH88] or Smyth and Plotkin [SP82].\n\n4.2. Elementary properties.\n\nThe following properties of the concepts introduced in the preceding section can easily be shown. Let \\( F, G : \\Pi C \\rightarrow C \\), \\( H : C \\rightarrow D \\) and \\( t, u \\in \\text{Tvar} \\). Then\n\n1. \\( F = P_t \\circ \\text{Id}[F/t] \\), \\hspace{1cm} (4.2.1)\n2. if \\( t \\neq u \\) then \\( P_u \\) is independent of \\( t \\), \\hspace{1cm} (4.2.2)\n3. \\( \\text{abstr}_u F \\) is independent of \\( u \\), \\hspace{1cm} (4.2.3)\n4. if \\( F \\) is independent of \\( t \\), then \\( \\text{abstr}_u F \\) is independent of \\( t \\), \\hspace{1cm} (4.2.4)\n5. if \\( F \\) is independent of \\( u \\), then \\( \\text{abstr}_u (F \\circ \\text{Id}[P_u/t]) = \\text{abstr}_t F \\), \\hspace{1cm} (4.2.5)\n6. if \\( G \\) is independent of \\( u \\) and \\( t \\neq u \\), then\n\\[ \\text{abstr}_u (F \\circ \\text{Id}[G/t]) = (\\text{abstr}_u F) \\circ \\text{Id}[G/t]. \\] \\hspace{1cm} (4.2.6)\n4.3. Definition of semantics of type expression.\n\nWe first show that with every type expression an $\\omega$-continuous functor $\\mathcal{I}C \\to C$ can be associated. Define $\\mathcal{F} : \\text{TypeExp} \\to [\\mathcal{I}C \\to C]$ by\n\n- $\\mathcal{F}[\\Omega] = \\text{CONST}_A$, where $A$ is the one-point c.p.o.\n- $\\mathcal{F}[t] = P_t$,\n- $\\mathcal{F}[\\text{ite}] = \\text{LIFT} \\circ \\mathcal{F}[\\text{te}]$,\n- $\\mathcal{F}[\\text{te1 + te2}] = \\text{DS} \\circ \\langle \\mathcal{F}[\\text{te1}], \\mathcal{F}[\\text{te2}] \\rangle$, \n- $\\mathcal{F}[\\text{te1 x te2}] = \\text{CP} \\circ \\langle \\mathcal{F}[\\text{te1}], \\mathcal{F}[\\text{te2}] \\rangle$, \n- $\\mathcal{F}[\\text{te1} \\to \\text{te2}] = \\text{FS} \\circ \\langle \\mathcal{F}[\\text{te1}], \\mathcal{F}[\\text{te2}] \\rangle$, \n- $\\mathcal{F}[\\text{te1} \\otimes \\text{te2}] = \\text{CS} \\circ \\langle \\mathcal{F}[\\text{te1}], \\mathcal{F}[\\text{te2}] \\rangle$, \n- $\\mathcal{F}[\\text{te1} \\sqcap \\text{te2}] = \\text{SP} \\circ \\langle \\mathcal{F}[\\text{te1}], \\mathcal{F}[\\text{te2}] \\rangle$, \n- $\\mathcal{F}[\\nu(A \\ t | \\text{te})] = \\text{IFP} \\circ (\\text{abstr}_t \\mathcal{F}[\\text{te}])$.\n\nThe constant and projection functors are trivially $\\omega$-continuous. The $\\omega$-continuity of the functors $\\text{DS}, \\text{CP}, \\text{FS}, \\text{CS}, \\text{SP}$ and $\\text{SF}$ follows from the local continuity of the corresponding functors on $\\text{CPO} \\times \\text{CPO}$ respectively $\\text{CPO}_\\perp \\times \\text{CPO}_\\perp$, see for instance Smyth & Plotkin [SP82] or Bos & Hemerik [BH88]. The $\\omega$ continuity of the functor $\\text{LIFT}$ follows from the local continuity of the corresponding functor $\\text{CPO} \\to \\text{CPO}_\\perp$, see also [SP82] or [BH88]. Further if $F : [\\mathcal{I}C \\to C]$ then also $\\text{abstr}_F : [\\mathcal{I}C \\to [C \\to C]]$, see for instance Herrlich & Strecker [HeStr73, th.15.9]. The $\\omega$-continuity of the initial fixed point functor $\\text{IFP}$ is shown in Lehmann & Smyth [LS81]. Now using the property that the composition of two $\\omega$-continuous functors is again $\\omega$-continuous (see Mac Lane [McL71]), it is easily shown by induction on the structure of $\\text{te}$ that $\\mathcal{F}[\\text{te}]$ is an $\\omega$-continuous functor for every type expression $\\text{te}$.\n\nDefine $\\text{Tenv} = \\text{obj}(\\mathcal{I}C)$. Elements of $\\text{Tenv}$ will be called type environments. If $\\rho \\in \\text{Tenv}$, then $\\rho_t = P_t(\\rho)$ is the c.p.o. associated to $t \\in \\text{Tvar}$ by the type environment $\\rho$. The c.p.o.\ncorresponding to a type expression $te$ in the environment $\\rho$ is given by $\\mathcal{T}[te]\\rho$.\n\n4.4. Properties of the type semantics.\n\nWe now describe some properties of the semantics of type expressions. Theorem 4.4.4. shows that the functor associated to a type expression $te$ depends only on the type variables which appear freely in $te$. Hence the c.p.o. which corresponds to $te$ in an environment $\\rho$ depends only on the values of $\\rho$ on $FTV(te)$.\n\nTheorem 4.4.1.\n\nLet $te \\in Texp$ and $t \\in Tvar$. If $t \\in FTV(te)$ then $\\mathcal{T}[te]$ is independent of $t$.\n\nProof. The theorem is easily proved using induction on the structure of $te$.\n\ni) $te = \\Omega$, then $\\mathcal{T}[te] = \\text{CONST}_A$, where $A$ is the one-point c.p.o. Clearly this functor is independent of $t$.\n\nii) $te = u \\in Tvar$ with $u \\not\\equiv t$. Then $\\mathcal{T}[te] = P_u$, which by property (4.4.2) is independent of $t$.\n\niii) $te = \\uparrow te_1$, $te = te_1 + te_2$, $te = te_1 \\times te_2$, $te = te_1 \\rightarrow te_2$, $te = te_1 \\ominus te_2$, $te = te_1 \\otimes te_2$ and $te = te_1 \\ominus te_2$. These cases are easily handled using the induction hypothesis that $\\mathcal{T}[te_1]$ respectively $\\mathcal{T}[te_1]$ and $\\mathcal{T}[te_2]$ are independent of $t$.\n\niv) $te = v(\\Lambda u | te)$. Then $\\mathcal{T}[v(\\Lambda u | te)] = \\text{IFP} \\circ (\\text{abstr}_u \\mathcal{T}[te])$. If $t = u$ the result follows from property (4.2.3). If $t \\not= u$ then $t \\in FTV(te_1)$ and the theorem follows from the induction assumption and property (4.2.4).\n\n$\\Box$\n\nThe next theorem gives the behaviour of $\\mathcal{T}[te]$ under substitution in $te$. \n\n32\nTheorem 4.4.2. [substitution in type expressions]\n\nLet \\( t e 1, t e 2 \\in Texp \\) and \\( t \\in Tvar \\). Then \\( \\mathcal{F}[t e 1 \\uparrow_{t e 2}] = \\mathcal{F}[t e 1] \\circ \\text{Id}[\\mathcal{F}[t e 2] / t] \\).\n\nProof. The proof is done by induction on the structure of \\( t e 1 \\).\n\ni) \\( t e 1 = \\Omega \\) or \\( t e 1 = s \\) with \\( s \\in Tvar \\) and \\( s \\neq t \\). In these cases \\( t \\in \\text{FTV}(t e 1) \\) and the theorem follows from theorem 4.4.1.\n\nii) \\( t e 1 = t \\). A simple calculation yields that\n\n\\[\n\\mathcal{F}[t \\uparrow_{t e 2}] = \\mathcal{F}[t e 2] = \\text{P}_t \\circ \\text{Id}[\\mathcal{F}[t e 2] / t] \\quad [\\text{property 4.2.1}]\n\\]\n\n\\[\n= \\mathcal{F}[t] \\circ \\text{Id}[\\mathcal{F}[t e 2] / t].\n\\]\n\niii) \\( t e 1 = \\uparrow t e \\). Then we have\n\n\\[\n\\mathcal{F}[(\\uparrow t e) \\uparrow_{t e 2}] = \\mathcal{F}[(\\uparrow t e) \\uparrow_{t e 2}] = \\text{LIFT} \\circ \\mathcal{F}[t e 2] \\quad [\\text{induction hypothesis}]\n\\]\n\n\\[\n= \\mathcal{F}[\\uparrow t e] \\circ \\text{Id}[\\mathcal{F}[t e 2] / t].\n\\]\n\niv) \\( t e 1 = t e 3 \\land t e 4 \\) where \\( \\land = +, \\times, \\rightarrow, \\odot, \\bigodot \\) corresponds to respectively \\( \\text{FU} = \\text{DS}, \\text{CP}, \\text{FS}, \\text{CS}, \\text{SP}, \\text{SF} \\). The result follows from the following computation.\n\n\\[\n\\mathcal{F}[(t e 3 \\land t e 4) \\uparrow_{t e 2}] = \\mathcal{F}[t e 3 \\uparrow_{t e 2} \\land t e 4 \\uparrow_{t e 2}] = \\text{FU} \\circ <\\mathcal{F}[t e 3 \\uparrow_{t e 2}], \\mathcal{F}[t e 4 \\uparrow_{t e 2}]> \\quad [\\text{induction hypothesis}]\n\\]\n\n\\[\n= \\text{FU} \\circ <\\mathcal{F}[t e 3], \\mathcal{F}[t e 4] > \\circ \\text{Id}[\\mathcal{F}[t e 2] / t] \\quad [<\\text{F1oF, F2oF}> = <\\text{F1,F2}>o\\text{F}]\n\\]\n\n\\[\n= \\mathcal{F}[t e 3 \\land t e 4] \\circ \\text{Id}[\\mathcal{F}[t e 2] / t].\n\\]\n\nv) \\( t e 1 = v(\\Lambda s | t e) \\). Let \\( u \\) be the first variable such that \\( u \\neq t \\) and \\( u \\notin \\text{FTV}(t e) \\cup \\text{FTV}(t e 2) \\). The result now follows from the following calculation.\nAs a consequence of theorem 4.4.2 we have\n\n\\[ \\mathcal{F}[\\nu(\\Lambda \\mathbf{s} | \\mathbf{t})_{\\mathbf{te}_2}] = \\mathcal{F}[\\nu(\\Lambda \\mathbf{u} | (\\mathbf{te}_2)^{\\mathbf{u}})_{\\mathbf{te}_2}] \\] \n\nfor all \\( \\mathbf{te}_1, \\mathbf{te}_2 \\in \\mathbf{T}_{\\mathbf{exp}} \\), \\( \\mathbf{t} \\in \\mathbf{T}_{\\mathbf{var}} \\) and \\( \\mathbf{\\rho} \\in \\mathbf{T}_{\\mathbf{env}} \\). This relation shows that substitution in a type expressions can be replaced by substitution in the type environment.\n\nAs expected, the semantics of a recursively defined type does not depend on the name of the bound variable.\n\nTheorem 4.4.4.\n\nLet \\( \\mathbf{te} \\in \\mathbf{T}_{\\mathbf{exp}} \\) and \\( \\mathbf{t}, \\mathbf{u} \\in \\mathbf{T}_{\\mathbf{var}} \\). If \\( \\mathbf{u} \\notin \\mathbf{FTV}(\\mathbf{te}) \\), then\n\n\\[ \\mathcal{F}[\\nu(\\Lambda \\mathbf{t} | \\mathbf{te})] = \\mathcal{F}[\\nu(\\Lambda \\mathbf{u} | \\mathbf{te}_2^{\\mathbf{u}})]. \\]\n\nProof. Using the previous theorem this result can be proved by a straightforward calculation.\n\n\\[ \\mathcal{F}[\\nu(\\Lambda \\mathbf{t} | \\mathbf{te}_2^{\\mathbf{u}})] = \\mathcal{F}[\\nu(\\Lambda \\mathbf{t} | \\mathbf{te}_2^{\\mathbf{u}})] \\]\nFinally we mention a technical result which will be used in section 5. From part v) of the\nproof of theorem 4.4.2. we infer that if $u \\not\\approx t$ and $t \\notin \\text{FTV}(te) \\cup \\text{FTV}(te2)$, then\n\n$$\\text{abstr}_u \\mathcal{F}[\\langle te^s, t \\rangle_{te2}] = (\\text{abstr}_s \\mathcal{F}[te]) \\circ \\text{Id}[\\mathcal{F}[te2] \\setminus t].$$\n\nHence we see that under the same assumptions\n\n$$(\\text{abstr}_u \\mathcal{F}[\\langle te^s, t \\rangle_{te2}]) \\rho = \\text{abstr}_s \\mathcal{F}[te] \\circ (\\rho[\\mathcal{F}[te2] \\setminus t])$$\n\n(4.4.5)\n\nfor every type assignment $\\rho$. \n\n= IFP \\circ \\text{abstr}_\\mathcal{F}[te]$ \\\\\n= \\mathcal{F}[\\forall (\\wedge t | te)].$\n\n[\\mathcal{F}[te]] is independent of $u$, property 4.2.5.]\n5.1. States.\n\nThe value of an expression \\( e \\in \\text{WTE}(A) \\) depends on the values of the free variables occurring in it. The function that defines these values is called a state. Hence a state maps each free variable of an expression to an element of a specific c.p.o. Which c.p.o. that is depends on the assumption \\( A \\) and the type environment \\( \\rho \\). Therefore we define for \\( A \\in \\text{Assumptions} \\) and \\( \\rho \\in \\text{Tenv} \\)\n\n\\[\n\\text{ST}_{\\rho, A} = \\Pi \\{ \\mathcal{F}[\\tau_A(x)]_\\rho \\mid x \\in \\text{WTV}(A) \\} \\tag{5.1.1}\n\\]\n\ni.e. the set of functions \\( \\sigma \\) such that \\( \\sigma(x) \\in \\mathcal{F}[\\tau_A(x)]_\\rho \\) for all \\( x \\in \\text{WTV}(A) \\). Elements of \\( \\text{ST}_{\\rho, A} \\) are called states.\n\nDefinition 5.1.2.\n\nLet \\( A \\in \\text{Assumptions} \\) and \\( \\rho \\in \\text{Tenv} \\). Moreover, let \\( x \\in \\text{Var} \\) and \\( tx \\in \\text{Texp} \\) such that \\( \\vdash A \\triangleright tx \\) and let \\( d \\in \\mathcal{F}[tx]_\\rho \\). Then for \\( \\sigma \\in \\text{ST}_{\\rho, A} \\) we define the function \\( \\sigma[d/x] \\in \\text{ST}_{\\rho,A,x:tx} \\) by:\n\n\\[\n\\sigma[d/x](y) = \\begin{cases} \n\\sigma(y) & \\text{if } y = x \\\\\n\\sigma(x) & \\text{if } y \\neq x\n\\end{cases}\n\\]\n\nMoreover, for \\( A_1 \\in \\text{Assumptions} \\) and \\( \\rho_1 \\in \\text{Tenv} \\) such that \\( \\text{WTV}(A_1) \\subseteq \\text{WTV}(A) \\) and \\( \\mathcal{F}[\\tau_A(x)]_\\rho = \\mathcal{F}[\\tau_A(x)]_{\\rho_1} \\) for all \\( x \\in \\text{WTV}(A_1) \\) we define the restriction \\( \\sigma \\uparrow \\text{WTV}(A_1) \\in \\text{ST}_{\\rho_1,A_1} \\) by:\n\n\\[\n(\\sigma \\uparrow \\text{WTV}(A_1))(x) = \\sigma(x)\n\\]\n\nNote that if also \\( \\vdash A_1 \\triangleright tx \\) then\n\n\\[\n\\sigma[d/x] \\uparrow (\\text{WTV}(A_1;x:tx)) = (\\sigma \\uparrow \\text{WTV}(A_1))[d/x] \\tag{5.1.3}\n\\]\n5.2. Semantic mappings\n\nThe meaning of an expression $e$ is given by a family of mappings $\\mathcal{E} = \\{ \\mathcal{E}_pA | p \\in \\text{Tenv}, A \\in \\text{Assumptions} \\}$ such that for $p$ and $A$ the domain of $\\mathcal{E}_pA$ is $\\text{WTE}(A)$ and for all expressions $e \\in \\text{WTE}(A)$ we have $\\mathcal{E}_pA[e] \\in \\text{ST}_pA \\rightarrow \\mathcal{F}[\\tau_A(e)]p$. Hence given a state $\\sigma \\in \\text{ST}_pA$, $\\mathcal{E}_pA[e]\\sigma$ indeed yields a value in the domain $\\mathcal{F}[\\tau_A(e)]p$.\n\nDefinition 5.2.1. [Semantic mapping $\\mathcal{E}_pA$]\n\nLet $p \\in \\text{Tenv}$ and $A \\in \\text{Assumptions}$. For all $t, tx \\in \\text{Tvar}; te, te1 \\in \\text{Texp}; x \\in \\text{Var}; e, e1, e2, f1, f2 \\in \\text{Exp}$ and $\\sigma \\in \\text{ST}_pA$, the mapping $\\mathcal{E}_pA \\in \\Pi \\{ \\text{ST}_pA \\rightarrow \\mathcal{F}[\\tau_A(e)]p | e \\in \\text{WTE}(A) \\}$ is defined by:\n\n1. $\\mathcal{E}_pA[(\\text{btm} | te)]\\sigma = \\perp_D$\n where $D = \\mathcal{F}[te]p$\n\n2. $\\mathcal{E}_pA[x]\\sigma = \\sigma(x)$\n\n3.1. $\\mathcal{E}_pA[(\\text{up} e)]\\sigma = \\langle 0, \\mathcal{E}_pA[e]\\sigma \\rangle \\uparrow_D$\n where $D = \\mathcal{F}[\\tau_A(x)]p$\n\n3.2. $\\mathcal{E}_pA[(\\text{down} e)]\\sigma = \\begin{cases} \\perp_D \\rightarrow \\perp_D & \\text{if } \\mathcal{E}_pA[e]\\sigma = \\perp_D \\\\ \\langle 0, d \\rangle \\uparrow_D \\rightarrow d & \\text{if } \\mathcal{E}_pA[e]\\sigma = \\langle 0, d \\rangle \\uparrow_D \\\\ \\text{fi} \\end{cases}$\n where $D = \\mathcal{F}[\\tau_A(x)]p$\n\n4.1. $\\mathcal{E}_pA[(\\text{inl} e1 | te2)]\\sigma = \\langle 1, \\mathcal{E}_pA[e1]\\sigma \\rangle_{D1+D2}$\n $\\mathcal{E}_pA[(\\text{inls} e1 | te2)]\\sigma = \\langle 1, \\mathcal{E}_pA[e1]\\sigma \\rangle_{D1 \\Theta D2}$\n where $D_1 = \\mathcal{F}[\\tau_A(e1)]p$, $D_2 = \\mathcal{F}[te2]p$\n4.2. \\( \\mathcal{E}_{\\rho, A}[\\text{inr tel} | e2] \\sigma = <2, \\mathcal{E}_{\\rho, A}[e2] \\sigma >_{D_1 + D_2} \\)\n\n\\( \\mathcal{E}_{\\rho, A}[\\text{inrs tel} | e2] \\sigma = <2, \\mathcal{E}_{\\rho, A}[e2] \\sigma >_{D_1 \\otimes D_2} \\)\n\nwhere \\( D_1 = \\mathcal{F}[\\text{tel}] \\rho \\), \\( D_2 = \\mathcal{F}[\\tau_A(e2)] \\rho \\)\n\nnote that \\( <1, \\perp >_{D_1 \\oplus D_2} = \\perp _{D_1 \\oplus D_2} = <2, \\perp >_{D_1 \\oplus D_2} \\).\n\n4.3. \\( \\mathcal{E}_{\\rho, A}[\\text{sum f1 f2}] \\sigma = \\)\n\n\\[ \\begin{align*}\n\\lambda d &\\in D_1 + D_2 \\\\\n| \\text{if } d &\\in \\perp _{D_1 + D_2} \\rightarrow \\perp \\\\\\n| d = <1, d_1 >_{D_1 + D_2} &\\rightarrow (\\mathcal{E}_{\\rho, A}[f1] \\sigma)(d_1) \\\\\n| d = <2, d_2 >_{D_1 + D_2} &\\rightarrow (\\mathcal{E}_{\\rho, A}[f2] \\sigma)(d_2) \\\\\n\\text{fi}\n\\end{align*} \\]\n\nwhere \\( D_1 \\rightarrow D = \\mathcal{F}[\\tau_A(f1)] \\rho \\), \\( D_2 \\rightarrow D = \\mathcal{F}[\\tau_A(f2)] \\rho \\)\n\n\\( \\mathcal{E}_{\\rho, A}[\\text{sums f1 f2}] \\sigma = \\)\n\n\\[ \\begin{align*}\n\\lambda d &\\in D_1 \\oplus D_2 \\\\\n| \\text{if } d &\\in <1, d_1 >_{D_1 \\oplus D_2} \\rightarrow (\\mathcal{E}_{\\rho, A}[f1] \\sigma)(d_1) \\\\\n| d = <2, d_2 >_{D_1 \\oplus D_2} &\\rightarrow (\\mathcal{E}_{\\rho, A}[f2] \\sigma)(d_2) \\\\\n\\text{fi}\n\\end{align*} \\]\n\nwhere \\( D_1 \\rightarrow D = \\mathcal{F}[\\tau_A(f1)] \\rho \\), \\( D_2 \\rightarrow D = \\mathcal{F}[\\tau_A(f2)] \\rho \\)\n\n5.1. \\( \\mathcal{E}_{\\rho, A}[\\text{prol e}] \\sigma = \\pi_1(\\mathcal{E}_{\\rho, A}[e] \\sigma) \\)\n\n\\( \\mathcal{E}_{\\rho, A}[\\text{proor e}] \\sigma = \\pi_2(\\mathcal{E}_{\\rho, A}[e] \\sigma) \\)\n\nwhere \\( \\pi_1 = (\\lambda <d_1, d_2 >_{D_1 \\times D_2} \\in D_1 \\times D_2 | d_1) \\)\n\nand \\( \\pi_2 = (\\lambda <d_1, d_2 >_{D_1 \\times D_2} \\in D_1 \\times D_2 | d_2) \\)\n\nand \\( D_1 \\times D_2 = \\mathcal{F}[\\tau_A(e)] \\rho \\)\n5.2. $\\mathcal{E}_{\\rho, A}[(\\text{pros e})] \\sigma = \\psi_1(\\mathcal{E}_{\\rho, A}[e] \\sigma)$\n\n$\\mathcal{E}_{\\rho, A}[(\\text{pros e})] \\sigma = \\psi_2(\\mathcal{E}_{\\rho, A}[e] \\sigma)$\n\nwhere\n\n\\[\n\\psi_1 = (\\lambda \\langle d_1, d_2 \\rangle \\in D_1 \\otimes D_2 \\mid \\text{ if } d_2 = \\downarrow D_2 \\rightarrow \\downarrow D_1 \\uparrow d_2 \\neq \\downarrow D_2 \\rightarrow d_1 \\uparrow d_2 \\uparrow d_1 \\neq \\downarrow D_1 \\rightarrow d_2 \\uparrow d_1)\n\\]\n\nand\n\n\\[\n\\psi_2 = (\\lambda \\langle d_1, d_2 \\rangle \\in D_1 \\otimes D_2 \\mid \\text{ if } d_1 = \\downarrow D_1 \\rightarrow \\downarrow D_2 \\uparrow d_1 \\neq \\downarrow D_1 \\rightarrow d_2 \\uparrow d_1 \\neq \\downarrow D_1 \\rightarrow d_2 \\uparrow d_1)\n\\]\n\nand $D_1 \\otimes D_2 = \\mathcal{F}[\\tau_A(e)] \\rho$\n\nnote that $\\langle d_1, d_2 \\rangle \\in D_1 \\otimes D_2 \\Rightarrow \\downarrow D_1 \\otimes D_2 = \\langle \\downarrow D_1, \\downarrow d_2 \\rangle \\otimes D_1 \\otimes D_2$\n\n5.3. $\\mathcal{E}_{\\rho, A}[(\\text{prod e1 e2})] \\sigma = <\\mathcal{E}_{\\rho, A}[e1] \\sigma, \\mathcal{E}_{\\rho, A}[e2] \\sigma> \\sigma \\otimes D_1 \\otimes D_2$\n\n$\\mathcal{E}_{\\rho, A}[(\\text{prods e1 e2})] \\sigma = <\\mathcal{E}_{\\rho, A}[e1] \\sigma, \\mathcal{E}_{\\rho, A}[e2] \\sigma> \\sigma \\otimes D_1 \\otimes D_2$\n\n6.1. $\\mathcal{E}_{\\rho, A}[\\langle \\lambda x : t x \\mid e \\rangle] \\sigma = (\\lambda d \\in D \\mid \\mathcal{E}_{\\rho, A}[c] \\sigma[d/x])$\n\n$\\mathcal{E}_{\\rho, A}[\\langle \\lambda x : t x \\mid e \\rangle] \\sigma =$\n\n\\[\n(\\lambda d \\in D \\\\\n\\text{ if } d = \\downarrow D \\rightarrow \\downarrow E \\\\\n\\uparrow d \\neq \\downarrow D \\rightarrow \\mathcal{E}_{\\rho, A}[c] \\sigma[d/x] \\\\\n\\text{ ff})\n\\]\n\nwhere $A_1 = A;x : t x$, $D = \\mathcal{F}[tx] \\rho$, $E = \\mathcal{F}[\\tau_{A_1}(e)] \\rho$\n\n6.2. $\\mathcal{E}_{\\rho, A}[(\\text{appl f e})] \\sigma = \\mathcal{E}_{\\rho, A}[f] \\sigma (\\mathcal{E}_{\\rho, A}[e] \\sigma)$\n\n6.3. $\\mathcal{E}_{\\rho, A}[(\\text{appls f e})] \\sigma = \\mathcal{E}_{\\rho, A}[f] \\sigma (\\mathcal{E}_{\\rho, A}[e] \\sigma)$\n\n7. $\\mathcal{E}_{\\rho, A}[\\langle \\text{intro v}(\\Lambda t|te) \\mid e \\rangle] \\sigma = \\alpha^R(\\mathcal{E}_{\\rho, A}[e] \\sigma)$\n\n$\\mathcal{E}_{\\rho, A}[\\langle \\text{elim v}(\\Lambda t|te) \\mid e \\rangle] \\sigma = \\alpha^L(\\mathcal{E}_{\\rho, A}[e] \\sigma)$\n\nwhere $(D, (\\alpha^L, \\alpha^R))$ is the initial fixed point of the endofunctor $F = (\\text{abstr}_t \\mathcal{F}[te]) \\rho$\n\non the category $C = \\text{CPO}_{\\text{PR}}$ obtained by applying the inverse limit construction to the $\\omega$-chain $< F^n_{\\downarrow C}, F^n u \\mid 0 \\leq n >$ with $u$ the unique morphism from $\\downarrow C$ to $F(\\downarrow C)$. Note that $D = \\mathcal{F}[v(\\Lambda t|te)] \\rho$, $F(D) = \\mathcal{F}[te^t_{v(\\Lambda t|te)}] \\rho$, $\\alpha^L \\in \\text{Hom}(F(D), D)$\nCHAPTER 5\n\n\\[\n\\text{and } \\alpha^R \\in \\text{Hom}(D,F(D)), \\text{ cf}[BH88,SP82]\n\\]\n\n8. \\[\n\\mathcal{E}_{\\rho,A}[\\langle A \\mid t \\rangle t e]a = \\mathcal{E}_{\\rho_1,A_1}[e](\\sigma \\mid \\text{WTE}(A_1))\n\\]\nwhere \\( \\rho_1 = \\rho[\\mathcal{F}[t e] / t] \\), \\( A_1 = A_1 t \\)\n\nRemark. All clauses of definition 2.5.2 are of the form\n\n\\[\n\\mathcal{E}_{\\rho,A}[e]a = \\phi(\\mathcal{E}_{\\rho_1,A_1}[e_1]a_1, \\ldots, \\mathcal{E}_{\\rho_n,A_n}[e_n]a_n), 0 \\leq n\n\\]\nwhere \\( e_1, \\ldots, e_n \\) are the constituting subexpressions of \\( e \\), and \\( \\phi \\) is some function. This is a proper definition iff\n\n- if \\( e \\in \\text{WTE}(A) \\) then \\( e_i \\in \\text{WTE}(A_i) \\), for \\( 1 \\leq i \\leq n \\)\n- \\( \\phi: \\mathcal{F}[\\tau_{A_1}(e_1)]\\rho_1 \\times \\ldots \\times \\mathcal{F}[\\tau_{A_n}(e_n)]\\rho_n \\rightarrow \\mathcal{F}[\\tau_A(e)]\\rho \\)\n\nFor all clauses but 7 and 8 this is trivial. For clause 7 we consider the case \\( \\langle \\text{elim v}(A \\mid t) \\mid e \\rangle \\) only. The case \\( \\langle \\text{intro v}(A \\mid t) \\mid e \\rangle \\) will then be evident. For all \\( A \\in \\text{Assumptions} \\) such that \\( \\langle \\text{elim v}(A \\mid t) \\mid e \\rangle \\in \\text{WTE}(A) \\):\n\n(i) \\[\n\\mathcal{F}[\\tau_A(\\langle \\text{elim v}(A \\mid t) \\mid e \\rangle)]\\rho\n\\]\n= \\( \\mathcal{F}[\\text{v}(A \\mid t) e]\\rho \\)\n= \\( \\text{IFP} \\circ (\\text{abstr}_t \\mathcal{F}[t e])\\rho \\)\n= \\( \\text{IFP}(\\text{abstr}_t \\mathcal{F}[t e])\\rho \\)\n= \\( \\text{IFP}(\\text{F}) \\)\n\nBy rule ER7.2 it follows that \\( e \\in \\text{WTE}(A) \\) and, moreover,\n\n(ii) \\[\n\\mathcal{F}[\\tau_A(e)]\\rho\n\\]\n= \\( \\mathcal{F}[t e_{v(A \\mid t)}]\\rho \\)\n= \\( \\mathcal{F}[t e]\\rho[\\mathcal{F}[\\text{v}(A \\mid t)]\\rho / t] \\)\n= \\( \\mathcal{F}[t e]\\rho[\\text{IFP}(\\text{F}) / t] \\)\n= \\( ((\\text{abstr}_t \\mathcal{F}[t e])\\rho)\\text{IFP}(\\text{F}) \\)\n= \\( \\text{F}(\\text{IFP}(\\text{F})) \\)\n\n40\nSince $\\alpha^L$ is an embedding from $F(IFP(F))$ into $IFP(F)$ it follows that clause 7 is a proper definition. From rule ER8 it follows that if $(\\Lambda t| e)te1 \\in WTE(A)$ then $e \\in WTE(A_1)$. Since the introduction of the rightmost type variable $t$ in $A_1$ invalidates type assignments for variables in which the type expression depends on $t$ and that occur to the left of it (see rule ER2), it follows that $WTV(A_1) \\subseteq WTV(A)$. Moreover, for $x \\in WTV(A_1)$ it holds that $\\tau_{A_1}(x) = \\tau_A(x)$ and that $t \\notin FTV(\\tau_{A_1}(x))$. Hence\n\n$$\\begin{align*}\n\\mathcal{H}[\\tau_{A_1}(x)]\\rho_1 \\\\\n= \\mathcal{H}[\\tau_{A_1}(x)]\\rho[\\mathcal{H}[te1]\\rho / t] & \\quad \\text{[thm.4.4.1]} \\\\\n= \\mathcal{H}[\\tau_{A_1}(x)]\\rho \\\\\n= \\mathcal{H}[\\tau_A(x)]\\rho\n\\end{align*}$$\n\nand therefore $\\sigma \\upharpoonright WTV(A_1) \\in ST_{\\rho_1,A_1}$ is properly defined.\n\n$\\square$\n\nIn the sequel we shall frequently need to compare the meanings (values) of a single expression under similar assumptions and in similar states. The following property indicates that if these similarities are strong enough the respective values are equal.\n\n**Property 5.2.2.**\n\nFor all $A_1, A_2 \\in \\text{Assumptions}$; $\\rho \\in \\text{Tenv}$; $e \\in \\text{Exp}$; $\\sigma_1 \\in ST_{\\rho,A_1}$ and $\\sigma_2 \\in ST_{\\rho,A_2}$:\n\nIf\n\n- $\\vdash A_1 \\triangleright e : te$\n- $\\vdash A_2 \\triangleright e : te$\n- $\\sigma_1 \\upharpoonright WTV(A_2) = \\sigma_2 \\upharpoonright WTV(A_1)$\n\nThen $\\mathcal{E}_{\\rho,A_1}[e]\\sigma_1 = \\mathcal{E}_{\\rho,A_2}[e]\\sigma_2$\n\n$\\square$\n5.3. Substitution and α–conversion.\n\nIn order to prove the soundness of the β–reduction rules (see chapter 6) we have to determine the meaning of expressions containing substitutions. For each of the two kinds of substitutions in expressions (see chapter 1) we present a substitution theorem.\n\nTheorem 5.3.1. [Modification of type environment]\n\nFor all \\( A \\in \\text{Assumptions} ; \\rho \\in \\text{Tenv} ; t \\in \\text{Tvar} ; t \\in \\text{Texp} ; e \\in \\text{Exp} ; D \\in \\text{Obj}(\\text{CPO}_{\\text{pr}}) \\) and \\( \\sigma \\in \\text{ST}_{\\rho, A} : \\)\n\n\\[\n\\text{If } \\vdash A \\triangleright e : te \\quad \\text{Then } \\quad e \\in \\text{FTV}(e:te) \\]\n\nThen \\( E_{\\rho, A}[e] \\sigma = E_{\\rho_1, A_1}[e] \\sigma_1 \\)\n\nwhere \\( \\rho_1 = \\rho[D/t] , A_1 = A ; t \\) and \\( \\sigma_1 = \\sigma \\upharpoonright \\text{WTV}(A_1) \\)\n\nProof. By induction on the structure of expression \\( e \\). We prove only a limited number of difficult cases. Assume (*) and (**).\n\n1.1. Let \\( e = x \\)\n\n\\([(*),(**),\\text{ER11.1}]\\)\n\n1.2. \\( x \\in \\text{WTV}(A_1) \\)\n\n\\([(*),(**),\\text{ER11.1}]\\)\n\n1.3. \\( E_{\\rho, A}[e] \\sigma = \\sigma(x) = \\sigma_1(x) = E_{\\rho_1, A_1}[x] \\sigma_1 \\)\n\n\\([1.2), \\text{def.} E] \\]\n\n2.1. Let \\( e = (\\lambda y : ty \\mid f) \\)\n\n2.2. Let \\( d \\in \\mathcal{F}[ty] \\rho \\). Moreover, let \\( A_2 \\in \\text{Assumptions} \\) and \\( \\sigma_2 \\in \\text{ST}_{\\rho, A_2} \\) be such that \\( A_2 = A ; y : ty \\) and \\( \\sigma_2 = \\sigma[d/y] \\)\n\n2.3. Let \\( tf \\in \\text{Texp} \\) be such that \\( tf \\in \\text{Texp} \\) be such that \\( tf \\in \\text{Texp} \\)\n\n\\([(*), \\text{ER6.1}]\\)\n\na) \\( \\vdash A \\triangleright ty , tf \\)\n\nb) \\( \\vdash A_2 \\triangleright f : tf \\)\n\nc) \\( te = \\alpha ty \\rightarrow tf \\)\n\n2.4. \\( \\text{FTV}(e:te) = \\text{FTV}(ty) \\cup \\text{FTV}(f) \\cup \\text{FTV}(tf) \\)\n\n\\([2.1), (2.3c)]\\)\n2.5. a) \\( t \\in \\text{FTV}(ty) \\) \n b) \\( t \\in \\text{FTV}(f;tf) \\) \n\n2.6. \\( \\vdash A_2; t \\triangleright f : tf \\) \n\n2.7. \\( \\vdash A_1; y: ty \\triangleright f : tf \\) \n\n2.8. \\( \\text{WTV}(A_2; t) = \\text{WTV}(A_1; y: ty) \\) \n\n2.9. \\( (\\sigma_2 \\triangleright \\text{WTV}(A_2; t)) \\triangleright \\text{WTV}(A_1; y: ty) \\) \n \\[= (\\sigma[d/y] \\triangleright \\text{WTV}(A_2; t)) \\triangleright \\text{WTV}(A_1; y: ty) \\] \n \\[= (\\sigma[d/y] \\triangleright (\\text{WTV}(A_1; y: ty)) \\triangleright \\text{WTV}(A_2; t) \\) \n \\[= (\\sigma \\triangleright \\text{WTV}(A_1))[[d/y] \\triangleright \\text{WTV}(A_2; t) \\) \n \\[= \\sigma_1[[d/y] \\triangleright \\text{WTV}(A_2; t) \\] \n\n2.10. \\( \\mathcal{E}_{p,A}[[\\lambda y: ty \\mid f]] \\sigma \\) \n \\[= (\\lambda d \\in \\mathcal{F}[ty] \\triangleright \\mathcal{E}_{p,A_2}[f] \\triangleright \\sigma_2 ) \\) \n \\[= (\\lambda d \\in \\mathcal{F}[ty] \\triangleright \\mathcal{E}_{p,A_2}[[f]] \\sigma_2 \\triangleright \\text{WTV}(A_2; t) \\) \\] \n \\[= (\\lambda d \\in \\mathcal{F}[ty] \\triangleright \\mathcal{E}_{p,A_1,y: ty}[[f]] \\sigma_1[[d/y]] \\) \\] \n \\[= \\mathcal{E}_{p,A_1}[[\\lambda y: ty \\mid f]] \\sigma_1 \\] \n\n3.1. Let \\( \\varepsilon = (\\text{elim } v(A s \\mid tf) \\mid f) \\) \n\n3.2. a) \\( \\vdash A \\triangleright f : tf^S_{v(A s \\mid tf)} \\) \n b) \\( te = \\alpha v(A s \\mid tf) \\) \n\n3.3. \\( \\text{FTV}(f;tf^S_{v(A s \\mid tf)}) \\) \n \\[= \\text{FTV}(f) \\cup (\\text{FTV}(tf) \\setminus \\{s\\}) \\cup \\text{FTV}(v(A s \\mid tf)) \\] \n \\[= \\text{FTV}(f) \\cup \\text{FTV}(v(A s \\mid tf)) \\] \n \\[= \\text{FTV}((\\text{elim } v(A s \\mid tf) \\mid f) : v(A s \\mid tf)) \\] \n \\[= \\text{FTV}(e;te) \\] \n\n3.4. \\( t \\in \\text{FTV}(f;tf^S_{v(A s \\mid tf)}) \\land t \\in v(A s \\mid tf) \\) \n\n3.5. Let \\( (A, (\\alpha^L, \\alpha^R)) \\) be the unique IFP resulting from the inverse limit construction with functor \\( (\\text{abstr}_s \\mathcal{F}[(te)]) \\rho \\)\nCHAPTER 5\n\n3.6. Let $\\mathcal{B}_s(\\beta^L, \\beta^R)$ be the unique IFP resulting from the inverse limit construction with functor $(\\text{abstr}_s \\mathcal{F}[\\langle te \\rangle])\\rho[D/t]$\n\n3.7. Since $t \\in \\text{FTV}(v(\\Lambda s | tf))$, by (3.4), it follows that the functor $(\\text{abstr}_s \\mathcal{F}[\\langle tf \\rangle])\\rho$ is independent of $t$, i.e. $(\\text{abstr}_s \\mathcal{F}[\\langle tf \\rangle])\\rho = (\\text{abstr}_s \\mathcal{F}[\\langle tf \\rangle])\\rho[D/t]$\n\n3.8. $\\alpha^L = \\beta^L$\n\n3.9. $E_{\\rho,A}[(\\lambda (\\Lambda s | tf) | f)]^\\sigma$\n\n$= \\alpha^L (E_{\\rho,A}[f]^\\sigma)$\n\n$= \\beta^L (E_{\\rho',A'}[f]^\\sigma)$\n\n$= \\beta^L (E_{\\rho_1,A_1}[f]^\\sigma_1)$\n\n$= E_{\\rho_1,A_1}[(\\lambda (\\Lambda s | tf) | f)]^\\sigma_1$\n\n4.1. Let $e \\equiv (\\Lambda s | f) tf \\land s \\neq t$\n\n4.2. Let $A_2 \\in \\text{Assumptions}$; $\\rho_2 \\in \\text{Tenv}$ and $\\sigma_2 \\in \\text{ST}$ $\\rho_2.A_2$ be such that\n\n$A_2 = A ; s$\n\n$\\rho_2 = \\rho[\\mathcal{F}[tf] \\rho / s]$\n\n$\\sigma_2 = \\sigma \\uparrow \\text{WTV}(A_2)$\n\n4.3. Let $tf \\in \\text{Texp}$ be such that\n\na) $\\vdash A_2 \\vdash f : tf$\n\nb) $te = \\alpha^t tf^s$\n\n4.4. $\\text{FTV}(e : te)$\n\n$= \\text{FTV}(e) \\cup \\text{FTV}(tf^s_{tf1})$\n\n$= (\\text{FTV}(f) \\setminus \\{s\\}) \\cup \\text{FTV}(tf1) \\cup (\\text{FTV}(tf) \\setminus \\{s\\})$\n\n$= (\\text{FTV}(f:tf) \\setminus \\{s\\}) \\cup \\text{FTV}(tf1)$\n\n4.5. $t \\in \\text{FTV}(f:tf)$\n\n4.6. $\\rho_2[D/t] = \\rho_1[\\mathcal{F}[tf1] \\rho / s]$\n\n4.7. $\\vdash A_2 : t \\vdash f : tf$\n\n4.8. $\\vdash A_1 : s \\vdash f : tf$\n\n4.9. Since $\\text{WTV}(A_2 ; t) = \\text{WTV}(A_1 ; s)$ it follows that\n\n$(\\sigma_2 \\uparrow \\text{WTV}(A_2 ; t)) \\uparrow \\text{WTV}(A_1 ; s) = (\\sigma_1 \\uparrow \\text{WTV}(A_1 ; s)) \\uparrow \\text{WTV}(A_2 ; t)$\n4.10. \\[ \\varepsilon_{p,A}[(\\Lambda s \\mid f)tf]_I] \\sigma \\\\\n= \\varepsilon_{p,A_2}[f] \\sigma_2 \\\\\n= \\varepsilon_{p_2,A_2}[f] \\sigma_2 \\uparrow \\text{WTV}(A_2; t) \\\\\n= \\varepsilon_{p_2}[f] \\sigma_2 \\uparrow \\text{WTV}(A_2; t) \\\\\n= \\varepsilon_{p_1}[f] \\sigma_1 \\uparrow \\text{WTV}(A_1; s) \\\\\n= \\varepsilon_{p_1,A_1}[(\\Lambda s \\mid f)tf]_I] \\sigma_1 \\\\\n\\text{[def.} \\varepsilon \\text{]} \\\\\n\\text{[(4.3a),(4.5),IH]} \\\\\n\\text{[(4.6)]} \\\\\n\\text{[(4.7),(4.8),(4.9),prop.5.2.2]} \\\\\n\\text{[(def.} \\varepsilon \\text{)]}\n\n5.1. Let \\( e = (\\Lambda t \\mid f)tf \\)\n\n5.2. Let \\( tf \\in \\text{Texp} \\) be such that \n\n\\( a) \\vdash A_1 \\triangleright f : tf \\) \\\\\n\\( b) \\alpha \\equiv t \\uparrow f \\)\n\n5.3. \\( \\vdash A_1; t \\triangleright f : tf \\) \\\\\n\\text{[(5.2a)]}\n\n5.4. Since \\( \\text{WTV}(A_1) = \\text{WTV}(A_1; t) \\) it follows that \n\\( \\sigma_1 \\uparrow \\text{WTV}(A_1; t) = (\\sigma_1 \\uparrow \\text{WTV}(A_1; t)) \\uparrow \\text{WTV}(A_1) \\)\n\n5.5. \\( t \\in \\text{FTV}(tf) \\) \\\\\n\\text{[(**)]}\n\n5.6. \\( p[\\mathcal{F}[tf]_I] \\rho / t \\) \\\\\n\\( = p[D/t][\\mathcal{F}[tf]_I] \\rho / t \\) \\\\\n\\( = p_1[\\mathcal{F}[tf]_I] \\rho / t \\) \\\\\n\\( = p_1[\\mathcal{F}[tf]_I] \\rho[D/t] / t \\) \\\\\n\\( = p_1[\\mathcal{F}[tf]_I] \\rho_1 / t \\) \\\\\n\\text{[(5.5),thm4.4.1]}\n\n5.7. \\( \\varepsilon_{p,A}[(\\Lambda t \\mid f)tf]_I] \\sigma \\\\\n= \\varepsilon_{p_1}[f] \\sigma_1 \\\\\n= \\varepsilon_{p_1}[f] \\sigma_1 \\uparrow \\text{WTV}(A_1; t) \\\\\n= \\varepsilon_{p_1,A_1}[(\\Lambda t \\mid f)tf]_I] \\sigma_1 \\\\\n\\text{[def.} \\varepsilon \\text{]} \\\\\n\\text{[(5.2a),(5.3),(5.4),prop.5.2.2]} \\\\\n\\text{[(def.} \\varepsilon \\text{)]}\nCHAPTER 5\n\nTheorem 5.3.2. [Substitution of type expressions for type variables in expressions]\n\nFor all \\( \\rho \\in \\text{Tenv} ; A_1, A_2 \\in \\text{Assumptions} ; \\ t \\in \\text{Tvar} ; \\ te, te_1 \\in \\text{Texp} ; \\ e \\in \\text{Exp} \\) and \\( \\sigma \\in \\text{ST}_{\\rho, A_1; A_2; te_1} \\):\n\nIf\n\n\\[\n\\vdash A_1 \\triangleright te_1\n\\]\n\n\\[\n\\vdash A_1 ; t ; A_2 \\triangleright e ; te\n\\]\n\n\\( \\text{FTV}(A_1 ; t) \\cap \\text{FTV}(A_2) = \\emptyset \\) \\hspace{1cm} (***)\n\nThen\n\n\\[\n\\varepsilon_{\\rho, A_1 ; A_2; te_1}^t [e_{te_1}^t] \\sigma = \\varepsilon_{\\rho_1, A_1 ; t ; A_2}^t [e] \\sigma_1\n\\]\n\nwhere \\( \\rho_1 = \\rho[\\varepsilon[te_1] / t] \\) and \\( \\sigma_1 = \\sigma[\\omega \\text{WTV}(A_1 ; t ; A_2)] \\)\n\nProof. By induction on the structure of expression \\( e \\). We prove only a limited number of difficult cases. Assume \\((*)\\),(**) and (***)\n\n1.1. Let \\( e \\equiv x \\)\n\n1.2. \\( x \\in \\text{WTV}(A_1 ; t ; A_2) \\)\n\n1.3. \\( \\varepsilon_{\\rho, A_1 ; A_2; te_1}^t [x_{te_1}^t] \\sigma = \\varepsilon_{\\rho_1, A_1 ; t ; A_2}^t [x] \\sigma \\) \\hspace{1cm} [subst]\n\n\\[\n\\begin{align*}\n\\sigma(x) & = \\sigma_1(x) \\\\\n& = \\varepsilon_{\\rho_1, A_1 ; t ; A_2}^t [x] \\sigma_1\n\\end{align*}\n\\]\n\n[def.\\( \\varepsilon \\)]\n\n[1.2]]\n\n2.1. Let \\( e \\equiv (\\lambda \\ y . ty \\ y) \\)\n\n2.2. Let \\( tf \\in \\text{Texp} \\) be such that \\( \\text{FTV}(A_2 ; y ; ty) = \\text{FTV}(A_2) \\) \\hspace{1cm} [(***)]\n\n\\[\n\\begin{align*}\n\\text{a) } & \\vdash A_1 ; t ; A_2 \\triangleright ty , tf \\\\\n\\text{b) } & \\vdash A_1 ; t ; A_2 ; y . ty \\triangleright f : tf\n\\end{align*}\n\\]\n\n2.3. \\( \\text{FTV}(A_2 ; y ; ty) = \\text{FTV}(A_2) \\)\n\n2.4. \\( \\varepsilon[ty_{te_1}] \\rho = \\varepsilon[ty] \\rho_1 \\) \\hspace{1cm} [4.4.3]]\n\n2.5. Let \\( d \\in \\varepsilon[ty] \\rho_1 \\) . Moreover let \\( A_3 \\in \\text{Assumptions} \\) and \\( \\sigma_3 \\in \\text{ST}_{\\rho_1, A_1 ; t ; A_3} \\) be such that\n\n\\[\nA_3 = A_2 ; y . ty\n\\]\n\n\\[\n\\sigma_3 = \\sigma_1[d/y]\n\\]\n2.6. \\[ \\sigma[d/y] \\vdash WTV(A_1; t; A_3) \\]\n\\[ = (\\sigma \\vdash WTV(A_1; t; A_2))[d/y] \\]\n\\[ = \\sigma_1[d/y] \\]\n\\[ = \\sigma_3 \\]\n\n2.7. \\[ \\mathcal{E}_{\\rho,A_1;A_3^t}[R_{te_1}^t]\\sigma[d/y] \\]\n\\[ = \\mathcal{E}_{\\rho_1,A_1;A_3^t}[f](\\sigma[d/y] \\vdash WTV(A_1; t; A_3)) \\]\n\\[ = \\mathcal{E}_{\\rho_1,A_1;A_3^t}[f]\\sigma_3 \\]\n\n2.8. \\[ \\mathcal{E}_{\\rho,A_1;A_2^t}[\\lambda y:ty \\mid f_{te_1}^t]\\sigma \\]\n\\[ = \\mathcal{E}_{\\rho,A_1;A_2^t}[\\lambda y:ty^t \\mid f^t_{te_1}]\\sigma \\]\n\\[ = (\\lambda d \\in \\mathcal{T}[ty^t_{te_1}]p \\mid \\mathcal{E}_{\\rho,A_1;A_3^t}[R_{te_1}^t]\\sigma[d/y] ) \\]\n\\[ = (\\lambda d \\in \\mathcal{T}[ty]^t p_1 \\mid \\mathcal{E}_{\\rho_1,A_1;A_3^t}[f]\\sigma_3 ) \\]\n\\[ = \\mathcal{E}_{\\rho_1,A_1;A_2^t}[\\lambda y:ty \\mid f]\\sigma_1 \\]\n\n3.1. Let \\( e = (\\text{elim } v(\\Lambda s \\mid tf) \\mid f) \\) [ER7.2]\n\n3.2. \\( \\vdash A_1; t; A_2 \\triangleright f : tf^s \\]\n\n3.3. Let \\( r \\) be the first type variable such that\n\\[ r \\not\\in \\Gamma \\land r \\in FTV(tf) \\land r \\in FTV(te_1) \\]\n\n3.4. Let \\( (A, (\\alpha^L, \\alpha^R)) \\) be the unique initial fixed point resulting from the inverse limit construction\nwith functor \\( (\\text{abstr}_r \\mathcal{T}(tf_{te_1}^t))p \\)\n\n3.5. Let \\( (B, (\\beta^L, \\beta^R)) \\) be the unique initial fixed point resulting from the inverse limit construction\nwith functor \\( (\\text{abstr}_s \\mathcal{T}(tf))p_1 \\)\n\n3.6. \\( (\\text{abstr}_r \\mathcal{T}(tf_{te_1}^t))p = (\\text{abstr}_s \\mathcal{T}(tf))p_1 \\) [4.5.2]\n\n3.7. \\( \\alpha^L = \\beta^L \\) [3.4)-(3.6]\n\n3.8. \\[ \\mathcal{E}_{\\rho,A_1;A_2^t}[\\text{elim } v(\\Lambda s \\mid tf) \\mid f_{te_1}^t]\\sigma \\]\n\\[ = \\mathcal{E}_{\\rho,A_1;A_2^t}[\\text{elim } v(\\Lambda r \\mid (tf_{te_1}^t))^t]\\sigma \\]\n\\[ = [3.1, \\text{subst}] \\]\nCHAPTER 5\n\n4.1. Let \\( e' = (\\lambda s \\cdot f) t f_1 \\)\n\n4.2. Let \\( tf \\in T_{exp} \\) be such that\n\na) \\( \\vdash A_1 ; t ; A_2 ; s \\rightarrow f : tf \\)\n\nb) \\( te = \\alpha tf_s \\)\n\n4.3. Let \\( r \\) be the first type variable such that\n\n\\( r \\not= t \\land r \\not\\in FTV(te_1) \\land r \\not\\in FTV(f;tf) \\)\n\n4.4. Let \\( \\rho_n \\in T_{env} \\) and \\( A_n \\in \\text{Assumptions} \\) and \\( \\sigma_n \\in ST_{\\rho_n} A_n \\), \\( 2 \\leq n \\leq 5 \\), be such that\n\n\\[ \\rho_2 = \\rho_1[\\mathcal{F}[tf_1]\\rho_1/s] \\]\n\n\\[ \\sigma_2 = \\sigma_1 \\uparrow \\text{WTV}(A_1; t; A_2; s) \\]\n\n\\[ A_3 = (A_2; r)^t_{te_1} \\]\n\n\\[ \\rho_3 = \\rho[\\mathcal{F}[tf]^t_{te_1}\\rho/r] \\]\n\n\\[ \\sigma_3 = \\sigma \\uparrow \\text{WTV}(A_1; A_3) \\]\n\n\\[ A_4 = A_2; r \\]\n\n\\[ \\rho_4 = \\rho_3[\\mathcal{F}[te_1]\\rho_3/t] \\]\n\n\\[ \\sigma_4 = \\sigma_3 \\uparrow \\text{WTV}(A_1; t; A_4) \\]\n\n\\[ A_5 = A_4; s \\]\n\n\\[ \\rho_5 = \\rho_4[\\mathcal{F}[r]\\rho_4/s] \\]\n\n\\[ \\sigma_5 = \\sigma_4 \\uparrow \\text{WTV}(A_1; t; A_5) \\]\n\n4.5. \\( \\vdash A_1 ; t ; A_2 ; s ; r \\rightarrow f : tf \\) \\[ (4.2a),(4.3),ER11.1 \\]\n\n4.6. \\( \\vdash A_1 ; t ; A_4 \\rightarrow r \\) \\[ TR2 \\]\n\n4.7. \\( \\vdash A_1 ; t ; A_5 \\rightarrow f : tf \\) \\[ (4.5),ER12.1 \\]\n\n4.8. \\( \\vdash A_1 ; t ; A_4 \\rightarrow f_s^r : tf_s^r \\) \\[ (4.6),(4.7),ER14 \\]\n\n4.9. \\( t \\not\\in FTV(A_2; r) \\) \\[ (***),(4.3) \\]\n\n4.10. \\( \\rho_4 \\)\n\n\\[ = \\rho_5[\\mathcal{F}[te_1]\\rho_3/t] \\]\n\n\\[ = \\rho_5[\\mathcal{F}[te_1]\\rho[\\mathcal{F}[tf]^t_{te_1}\\rho/r]/t] \\]\n\n\\[ = \\rho_5[\\mathcal{F}[te_1]\\rho/t] \\]\n\n\\[ = \\rho[\\mathcal{F}[tf]^t_{te_1}\\rho/r][\\mathcal{F}[te_1]\\rho/t] \\]\n\n\\[ = \\rho[\\mathcal{F}[tf]^t_{te_1}\\rho_1/r][\\mathcal{F}[te_1]\\rho/t] \\]\n\n\\[ \\text{[def.}\\rho_4] \\]\n\n\\[ \\text{[def.}\\rho_3] \\]\n\n\\[ \\text{[def.}\\rho_3] \\]\n\n\\[ \\text{[(4.3),thm.4.4.1]} \\]\n\n\\[ \\text{[def.}\\rho_3] \\]\n\n\\[ \\text{[(4.4.3),def.}\\rho_1] \\]\n\\[\\begin{align*}\n\\rho \\circ [\\mathcal{T}[t_1]]_{\\rho / t} &= [\\mathcal{T}[t_1]]_{\\rho_1 / r} & ([4.3]) \\\\\n\\rho \\circ [\\mathcal{T}[t_1]]_{\\rho_1 / r} &= \\rho \\circ [\\mathcal{T}[t_1]]_{\\rho_1 / r} & ([\\text{def.} \\rho]) \\\\\n4.11. \\quad \\rho_5 &= \\rho_4[\\mathcal{T}[r]]_{\\rho_4 / s} & ([\\text{def.} \\rho_5]) \\\\\n&= \\rho_4[\\mathcal{T}[r]]_{\\rho_4 / s} & ([\\text{def.} \\mathcal{T}]) \\\\\n&= \\rho_4[(\\rho_1[\\mathcal{T}[t_1]]_{\\rho_1 / r})(r) / s] & ([4.10]) \\\\\n&= \\rho_4[\\mathcal{T}[t_1]]_{\\rho_1 / s} & ([4.10]) \\\\\n&= \\rho_1[\\mathcal{T}[t_1]]_{\\rho_1 / r}[\\mathcal{T}[t_1]]_{\\rho_1 / s} & ([\\text{def.} \\rho_2]) \\\\\n&= \\rho_2[\\mathcal{T}[t_1]]_{\\rho_1 / r} & ([\\text{def.} \\rho_2]) \\\\\n4.12. \\quad \\sigma_5 = \\sigma \\uparrow \\text{WTV}(A_1;t;A_2;r;s) &= \\sigma_2 \\uparrow \\text{WTV}(A_1;t;A_2;s;r) \\\\\n4.13. \\quad \\varepsilon_{\\rho,A_1;A_2}_{t_{t_1}^{t_1}} &\\vdash (\\Lambda t[f]_t)^t_{t_1} \\sigma & ([\\text{subst.},(3.1)]) \\\\\n&= \\varepsilon_{\\rho,A_1;A_2}_{t_{t_1}^{t_1}} & (\\Lambda t[f]_{t_1}^t)^t_{t_1} \\sigma_3 & ([\\text{def.} \\sigma_3, \\text{def.} \\varepsilon]) \\\\\n&= \\varepsilon_{\\rho_3,A_1;A_3} & \\sigma_3 & ([\\ast],(4.8),(4.9),\\text{IH}) \\\\\n&= \\varepsilon_{\\rho_4,A_1;t;A_4} & \\sigma_4 & ([\\ast],(4.5),(4.7),(4.12),\\text{prop.}5.2.2) \\\\\n&= \\varepsilon_{\\rho_5,A_1;t;A_2} & \\sigma_5 & ([4.2),(4.3),(4.11),\\text{thm}5.3.1) \\\\\n&= \\varepsilon_{\\rho_5,A_1;t;A_2} & \\sigma_5 & ([\\text{def.} \\sigma_2, \\text{def.} \\varepsilon]) \\\\\n\\square\n\\end{align*}\\]\n\n**Theorem 5.3.3** [Renaming a bound type variable]\n\nFor all \\( \\rho \\in \\text{Tenv} ; A \\in \\text{Assumptions} ; s, t \\in \\text{Tvar} ; \\text{te}, \\text{te}_1 \\in \\text{Texp} ; e \\in \\text{Exp} \\) and \\( \\sigma \\in \\text{ST} ; \\rho.A : A \\):\n\n\\[\\begin{align*}\n\\vdash A \\triangleright \\text{te}_1 & \\quad (\\ast) \\\\\n\\vdash A;t \\triangleright e;te & \\quad (\\ast\\ast) \\\\\n\\text{s} \\in \\text{FTV}(e;te) & \\quad (\\ast\\ast\\ast)\n\\end{align*}\\]\nCHAPTER 5\n\nThen \\( \\varepsilon_{\\rho,A}[(\\Lambda t\\mid e)\\text{te}1]\\sigma = \\varepsilon_{\\rho,A}[(\\Lambda s\\mid e^t_s)\\text{te}1]\\sigma \\)\n\nProof. Assume (*),(**) and (***)\n\n1. Let \\( \\rho_1,\\rho_2 \\in \\text{Tenv} \\); \\( A_1,A_2 \\in \\text{Assumptions} \\) and \\( \\sigma_1 \\in \\text{ST} \\rho_1,A_1 \\); \\( \\sigma_2 \\in \\text{ST} \\rho_2,A_2 \\) be such that\n\\[\nA_1 = A; t \\quad \\rho_1 = \\rho[\\mathcal{F}[\\text{te}1]p / t] \\quad \\sigma_1 = \\sigma^t\\text{WTV}(A_1)\n\\]\n\\[\nA_2 = A; s \\quad \\rho_2 = \\rho[\\mathcal{F}[\\text{te}1]p / s] \\quad \\sigma_2 = \\sigma^s\\text{WTV}(A_2)\n\\]\n\n2. \\( \\vdash A_2 \\triangleright s \\) \\hspace{1cm} [(1),TR2]\n\n3. \\( \\vdash A_1; s \\triangleright e : te \\) \\hspace{1cm} [(1),(**),(***)],ER11.1\n\n4. Since \\( \\text{FTV}(A) \\subseteq \\text{FTV}(A_2) \\) it follows from (*) and prop.2.4.1 that\n\\( \\vdash A_2 \\triangleright \\text{te}1 \\) \\hspace{1cm} [(3),ER12.1]\n\n5. \\( \\vdash A_1; t \\triangleright e : te \\) \\hspace{1cm} [(3),ER12.1]\n\n6. \\( (\\sigma_2 \\upharpoonright \\text{WTV}(A_2; t)) \\upharpoonright \\text{WTV}(A_1; s) \\)\n\\( = (\\sigma \\upharpoonright \\text{WTV}(A_2; t)) \\upharpoonright \\text{WTV}(A_1; s) \\)\n\\( = (\\sigma_1 \\upharpoonright \\text{WTV}(A_1; s)) \\upharpoonright \\text{WTV}(A_2; t) \\)\n\n7. \\( \\rho_2[\\mathcal{F}[s]p_2 / t] \\)\n\\( = \\rho_2[\\rho_2(s) / t] \\) \\hspace{1cm} [def.\\mathcal{F}]\n\\( = \\rho_2[\\mathcal{F}[te1]p / t] \\) \\hspace{1cm} [(1)]\n\\( = \\rho[\\mathcal{F}[te1]p / s][\\mathcal{F}[te1]p / t] \\) \\hspace{1cm} [(1)]\n\\( = \\rho[\\mathcal{F}[te1]p / t][\\mathcal{F}[te1]p / s] \\) \\hspace{1cm} [(1)]\n\\( = \\rho_1[\\mathcal{F}[te1]p / s] \\)\n\n8. \\( \\varepsilon_{\\rho,A}[(\\Lambda s\\mid e^t_s)\\text{te}1]\\sigma \\)\n\\( = \\varepsilon_{\\rho_2,A_2}[e^t_s]\\sigma_2 \\) \\hspace{1cm} [def.\\varepsilon]\n\\( = \\varepsilon_{\\rho_2[\\mathcal{F}[s]p_2 / t],A_2; t}[e]\\sigma_2 \\upharpoonright \\text{WTV}(A_2; t) \\)\n\\( = \\varepsilon_{\\rho_2[\\mathcal{F}[s]p_2 / t],A_1; s}[e]\\sigma_1 \\upharpoonright \\text{WTV}(A_1; s) \\)\n\\( = \\varepsilon_{\\rho_1[\\mathcal{F}[te1]p / s],A_1; s}[e]\\sigma_1 \\upharpoonright \\text{WTV}(A_1; s) \\)\n\\( = \\varepsilon_{\\rho_1,A_1}[e]\\sigma_1 \\) \\hspace{1cm} [(**),(***)],thm5.3.1]\nTheorem 5.3.4. [State modification]\n\nFor all \\( A \\in \\text{Assumptions; } \\rho \\in \\text{Tenv}; \\; te, te_1 \\in \\text{Texp; } x \\in \\text{Var; } e \\in \\text{Exp; } \\sigma \\in \\text{ST}_{\\rho, A} \\) and \\( d_1 \\in \\mathcal{F}[te_1]\\rho : \\)\n\nIf \\( \\vdash A \\triangleright te_1 \\)\n\nThen \\( \\mathcal{E}_{\\rho, A}[e] \\sigma = \\mathcal{E}_{\\rho, A_1}[e] \\sigma_1 \\)\n\nwhere \\( A_1 = A; x: te_1 \\) and \\( \\sigma_1 = \\sigma[d_1/x] \\)\n\nProof. By induction to the structure of expression \\( e \\). We prove only a limited number of difficult cases. Assume (*) and (**).\n\n1.1. Let \\( e \\equiv y \\)\n\n1.2. \\( y \\not\\equiv x \\) \\([**], (1.1)\\]\n\n1.3. \\( \\mathcal{E}_{\\rho, A}[y] \\sigma = \\sigma(y) = \\sigma_1(y) = \\mathcal{E}_{\\rho, A_1}[y] \\sigma_1 \\) \\([1.2]\\)\n\n2.1. Let \\( e \\equiv (\\lambda y: te_2 \\mid f) \\land x \\not\\equiv y \\)\n\n2.2. Let \\( d_2 \\in \\mathcal{F}[te_2]\\rho \\) and let \\( A_2 \\in \\text{Assumptions and } \\sigma_2 \\in \\text{ST}_{\\rho, A_2} \\) be such that \\( A_2 = A; y: te_2 \\) \\( \\sigma_2 = \\sigma[d_2/y] \\)\n\n2.3. Let \\( tf \\in \\text{Texp} \\) be such that\n\n\\begin{itemize}\n \\item[a)] \\( \\vdash A \\triangleright te_2 , tf \\)\n \\item[b)] \\( \\vdash A_2 \\triangleright f : tf \\)\n \\item[c)] \\( te \\equiv_\\alpha te_2 \\rightarrow tf \\)\n\\end{itemize}\n\n2.4. \\( \\vdash A_2 \\triangleright te_1 \\) \\([**], \\text{ER6.1}\\]\n\n2.5. \\( x \\not\\in \\text{FV}(f) \\) \\([**], (2.1)]\\]\nCHAPTER 5\n\n2.6. \\( \\varepsilon_{\\rho,A_2} [f] \\sigma_2 = \\varepsilon_{\\rho,A_2;x:te1} [f] \\sigma_2[d/y/x] \\) \\[ (2.4),(2.3b),(2.5),IH \\]\n\n2.7. \\( \\vdash A_2;x:te1 \\triangleright f : tf \\) \\[ (2.3),(2.4),ER\\ref{11.2} \\]\n\n2.8. \\( \\vdash A_1;y:te2 \\triangleright f : tf \\) \\[ (2.5),ER\\ref{12.2} \\]\n\n2.9. \\( \\sigma_2[d/x/y] \\vdash \\text{WTV}(A_1;y:te2) = \\sigma_1[d/y] \\vdash \\text{WTV}(A_2;x:te1) \\) \\[ x \\neq y \\]\n\n2.10. \\( \\varepsilon_{\\rho,A}[(\\lambda \\ y:te2 \\mid f)]\\sigma \\)\n\n\\[ = (\\lambda \\ d_2 \\in \\mathcal{F}[te2] \\rho \\mid \\varepsilon_{\\rho,A_2} [f] \\sigma_2) \\] \\[ \\text{[def.}\\varepsilon] \\]\n\n\\[ = (\\lambda \\ d_2 \\in \\mathcal{F}[te2] \\rho \\mid \\varepsilon_{\\rho,A_2;x:te1} [f] \\sigma_2[d/y/x]) \\] \\[ (2.6) \\]\n\n\\[ = (\\lambda \\ d_2 \\in \\mathcal{F}[te2] \\rho \\mid \\varepsilon_{\\rho,A_1;y:te2} [f] \\sigma_1[d/y]) \\] \\[ (2.7),(2.8),(2.9),prop\\ref{5.2.2}\\]\n\n\\[ = \\varepsilon_{\\rho,A_1}[(\\lambda \\ y:te2 \\mid f)]\\sigma_1 \\] \\[ \\text{[def.}\\varepsilon] \\]\n\n3.1. Let \\( e = (\\Lambda x:te2 \\mid f) \\)\n\n3.2. Let \\( tf \\in \\text{Texp} \\) be such that \\[ (\\ast),ER\\ref{6.1} \\]\n\na) \\( \\vdash A \\triangleright te2, \\ tf \\)\n\nb) \\( \\vdash A;x:te2 \\triangleright f : tf \\)\n\nc) \\( te \\equiv \\alpha \\ ty \\rightarrow tf \\)\n\n3.3. \\( \\vdash A_1;x:te2 \\triangleright f : tf \\) \\[ (3.2b) \\]\n\n3.4. \\( \\sigma[d/x] \\vdash \\text{WTV}(A_1;x:te2) = \\sigma_1[d/x] \\vdash \\text{WTV}(A;x:te2) \\)\n\n3.5. \\( \\varepsilon_{\\rho,A}[(\\lambda \\ y:ty \\mid f)]\\sigma \\)\n\n\\[ = (\\lambda \\ d \\in \\mathcal{F}[ty] \\rho \\mid \\varepsilon_{\\rho,A_1;y:ty} [f] \\sigma[d/y]) \\] \\[ \\text{[def.}\\varepsilon] \\]\n\n\\[ = (\\lambda \\ d \\in \\mathcal{F}[ty] \\rho \\mid \\varepsilon_{\\rho,A_1;x:te1} [f] \\sigma[d/y]) \\] \\[ (3.3),(3.4),prop\\ref{5.2.2} \\]\n\n\\[ = \\varepsilon_{\\rho,A_1}[(\\lambda \\ y:ty \\mid f)]\\sigma_1 \\] \\[ \\text{[def.}\\varepsilon] \\]\n\n4.1. Let \\( e = (\\Lambda s \\mid f)tf1 \\)\n\n4.2. Assume without loss of generality that \\[ \\text{thm.5.3.3} \\]\n\n\\( s \\in \\text{FTV}(te1) \\)\n\n4.3. Let \\( A_2 \\in \\text{Assumptions and } \\sigma_2 \\in \\text{ST}_{\\rho_2,A_2} \\) be such that\n\n\\( A_2 = A_1; s \\)\n\n\\( \\rho_2 = \\rho[\\mathcal{F}[tf1] / s] \\)\n\n\\( \\sigma_2 = \\sigma \\vdash \\text{WTV}(A_2) \\)\n\n4.4. \\( \\vdash A_2 \\triangleright te1 \\) \\[ (\\ast),(4.2),ER\\ref{11.1} \\]\n4.5. Let $tf \\in Texp$ be such that\n\\[ \\vdash A_2 \\triangleright f : tf \\]\n\n4.6. \\( x \\notin FV(f) \\)\n\n4.7. \\( \\vdash A_2 ; x : tel \\triangleright f : tf \\)\n\n4.8. \\( \\vdash A_1 ; s \\triangleright f : tf \\)\n\n4.9. \\( \\sigma_2[d/x] \\uparrow WTV(A_1; s) \\)\n\\[ = (\\sigma \\uparrow WTV(A_2))[d/x] \\uparrow WTV(A_1; s) \\]\n\\[ = (\\sigma[d/x] \\uparrow WTV(A_2; x : tel)) \\uparrow WTV(A_1; s) \\]\n\\[ = (\\sigma_1 \\uparrow WTV(A_2; x : tel)) \\uparrow WTV(A_1; s) \\]\n\\[ = (\\sigma_1 \\uparrow WTV(A_1; s)) \\uparrow WTV(A_2; x : tel) \\]\n\n4.10. \\( \\varepsilon_{\\rho, A}[\\langle A_1 s | ftf1 \\rangle] \\sigma \\)\n\\[ = \\varepsilon_{\\rho_2, A_2}[f] \\sigma_2 \\]\n\\[ = \\varepsilon_{\\rho_2, A_2; x : tel}[f] \\sigma_2[d/x] \\]\n\\[ = \\varepsilon_{\\rho_2, A_1; s}[f] \\sigma_1 \\uparrow WTV(A_1; s) \\]\n\\[ = \\varepsilon_{\\rho, A_1}[\\langle A_1 s | ftf1 \\rangle] \\sigma_1 \\]\n\n\\[ \\square \\]\n\n**Theorem 5.3.5.** [Substitution of expressions for variables in expressions]\n\nFor all \\( \\rho \\in Tenv ; A \\in \\text{Assumptions} ; tel \\in Texp ; x \\in \\text{Var} ; e, e_1 \\in \\text{Exp} \\) and \\( \\sigma \\in ST_{\\rho, A} : \\)\n\nIf\n\\[ \\vdash A \\triangleright e_1 : tel \\]\n\\[ \\vdash A_1 \\triangleright e : te \\]\n\nThen\n\\[ \\varepsilon_{\\rho, A}[e_1^x] \\sigma = \\varepsilon_{\\rho, A_1}[e] \\sigma_1 \\]\n\nwhere \\( A_1 = A_1 ; x : tel \\) and \\( \\sigma_1 = \\sigma[\\varepsilon_{\\rho, A}[e_1^x] \\sigma / x] \\)\n\n**Proof.** By induction on the structure of expression \\( e \\). We prove only a few difficult cases.\n\nAssume (*) and (**).\nCHAPTER 5\n\n1.1. Let \\( e \\equiv x \\)\n\n1.2. \\[\n\\begin{align*}\n\\mathcal{E}_{\\rho,A} [x^e_1] \\sigma \\\\\n= \\mathcal{E}_{\\rho,A} [e_1] \\sigma \\\\\n= \\sigma \\left[ \\mathcal{E}_{\\rho,A} [e_1] \\sigma / x \\right] (x) \\\\\n= \\mathcal{E}_{\\rho,A_1} [x] \\sigma_1\n\\end{align*}\n\\]\n\n2.1. Let \\( e \\equiv y \\land y \\neq x \\)\n\n2.2. \\[\n\\begin{align*}\n\\mathcal{E}_{\\rho,A} [y^x_e] \\sigma = \\mathcal{E}_{\\rho,A} [y] \\sigma = \\sigma(y) = \\sigma_1(y) = \\mathcal{E}_{\\rho,A_1} [y] \\sigma_1\n\\end{align*}\n\\]\n\n3.1. Let \\( e \\equiv (\\lambda y : te2 \\mid f) \\)\n\n3.2. Let \\( z \\) be the first variable such that\n\n\\( z \\neq x \\land z \\not\\in \\text{FV}(f) \\land z \\not\\in \\text{FV}(e) \\)\n\n3.3. Let \\( D = \\mathcal{T}[te2]_{\\rho} \\) and \\( d \\in D \\)\n\n3.4. Let \\( A_n \\in \\text{Assumptions} \\) and \\( \\sigma_n \\in \\text{ST}_{\\rho,A_n} \\), \\( 2 \\leq n \\leq 5 \\), be such that\n\n\\begin{align*}\nA_2 &= A_1; y : te2 & \\sigma_2 &= \\sigma_1[d/y] \\\\\nA_3 &= A; z : te2 & \\sigma_3 &= \\sigma[d/z] \\\\\nA_4 &= A_3; x : te1 & \\sigma_4 &= \\sigma_3 \\left[ \\mathcal{E}_{\\rho,A_3} [e_1] \\sigma_3 / x \\right] \\\\\nA_5 &= A_4; y : te2 & \\sigma_5 &= \\sigma_4 \\left[ \\mathcal{E}_{\\rho,A_4} [z] \\sigma_4 / y \\right]\n\\end{align*}\n\n3.5. \\( \\vdash A_3 \\supset e_1 : te1 \\) \\( [(3.10) \\text{ in thm.2.5.4}] \\)\n\n3.6. \\( \\vdash A_4 \\supset f^y_z : tf \\) \\( [(3.8) \\text{ in thm.2.5.4}] \\)\n\n3.7. \\( \\vdash A_4 \\supset z : te2 \\) \\( [(3.7) \\text{ in thm.2.5.4}] \\)\n\n3.8. \\( \\vdash A_5 \\supset f : tf \\) \\( [(3.6) \\text{ in thm.2.5.4}] \\)\n\n3.9. \\[\n\\begin{align*}\n\\mathcal{E}_{\\rho,A_3} [e_1] \\sigma_3 = \\mathcal{E}_{\\rho,A} [e_1] \\sigma \\\\\n\\end{align*}\n\\]\n\n3.10. \\( \\vdash A_2; z : te2 \\supset f : tf \\) \\( [(3.5) \\text{ in thm.2.5.4}] \\)\n\n3.11. \\[\n\\begin{align*}\n\\sigma_5 &= \\sigma_4 \\left[ \\mathcal{E}_{\\rho,A_4} [z] \\sigma_4 / y \\right] \\quad \\text{[def.}\\sigma_5] \\\\\n&= \\sigma_4 [\\sigma_4(z) / y] \\quad \\text{[def.}\\mathcal{E}] \\\\\n&= \\sigma_4 [ (\\sigma[d/z] [\\mathcal{E}_{\\rho,A_3} [e_1] \\sigma_3 / x]) (z) / y] \\quad \\text{[(3.4)]}\n\\end{align*}\n\\]\n3.12.\n\\[ \\varepsilon_{\\rho, A}[(\\lambda y: \\text{te}_2 \\mid f)_{\\text{e}_1}]_{\\sigma} = \\varepsilon_{\\rho, A}[(\\lambda z: \\text{te}_2 \\mid (\\text{f}^y_{\\text{e}_1,z})^x_{\\text{e}_1}]_{\\sigma} \\]\n\\[ = (\\lambda \\text{d} \\in D \\mid \\varepsilon_{\\rho, A_3}[\\text{f}^y_{\\text{e}_1,z}]_{\\sigma_3}) \\] \n\\[ = (\\lambda \\text{d} \\in D \\mid \\varepsilon_{\\rho, A_4}[\\text{f}^y_{\\text{e}_1,z}]_{\\sigma_4}) \\] \n\\[ = (\\lambda \\text{d} \\in D \\mid \\varepsilon_{\\rho, A_5}[\\text{f}]_{\\sigma_5}) \\] \n\\[ = (\\lambda \\text{d} \\in D \\mid \\varepsilon_{\\rho, A_2; z: \\text{te}_2}[\\text{f}]_{\\sigma_2[d/z]}) \\]\n\\[ = \\varepsilon_{\\rho, A_1}[(\\lambda y: \\text{te}_2 \\mid f)]_{\\sigma_1} \\] \n\n4.1. Let \\( e \\equiv (\\Lambda s \\mid f)_{\\text{f}1} \\)\n\n4.2. Assume without loss of generality that \\( s \\in \\text{FTV(e1:te1)} \\)\n\n4.3. Let \\( A_2 \\in \\text{Assumptions } \\rho_2 \\in \\text{Tenv and } \\sigma_2 \\in \\text{ST}_{\\rho, A_2} \\) be such that\n\\[ A_2 = A; s \\]\n\\[ \\rho_2 = \\rho[\\text{f}1_{s}] \\rho / s \\]\n\\[ \\sigma_2 = \\sigma \\uparrow \\text{WTV}(A_2) \\] \n\n4.4. Let \\( tf \\in \\text{Texp} \\) be such that \\( \\vdash A_1; s \\triangleright tf \\)\n\n4.5. \\( \\vdash A_2 \\triangleright e_1 : \\text{te}_1 \\)\n\n4.6. \\( \\vdash A_2; x: \\text{te}_1 \\triangleright tf \\)\n\n4.7. \\( \\sigma \\uparrow \\text{WTV}(A_2) \\)\n\\[ = (\\sigma \\uparrow \\text{WTV}(A_2)) \\uparrow \\text{WTV}(A) \\]\n\\[ = \\sigma_2 \\uparrow \\text{WTV}(A) \\]\nCHAPTER 5\n\n4.8. \\( \\text{WTV}(A_1; s) \\subseteq \\text{WTV}(A_2; x: \\text{te1}) \\) \n\n4.9. \n\\[\n(\\sigma_2[\\varepsilon_{\\rho, A_2} [e_1] \\sigma / x]) \\uparrow \\text{WTV}(A_1; s)\n= (\\sigma_2[\\varepsilon_{\\rho, A} [e_1] \\sigma / x]) \\uparrow \\text{WTV}(A_1; s) \\\\\n= ((\\sigma \\uparrow \\text{WTV}(A_2))[\\varepsilon_{\\rho, A} [e_1] \\sigma / x]) \\uparrow \\text{WTV}(A_1; s) \\\\\n= (\\sigma[\\varepsilon_{\\rho, A} [e_1] \\sigma / x]) \\uparrow \\text{WTV}(A_2; x: \\text{te1}) \\uparrow \\text{WTV}(A_1; s) \\\\\n= (\\sigma_1 \\uparrow \\text{WTV}(A_2; x: \\text{te1})) \\uparrow \\text{WTV}(A_1; s)\n\\]\n\n4.10. \n\\[\n\\varepsilon_{\\rho, A} [(\\lambda s \\mid f)\\text{te1}]^X_{e_2}\\sigma\n= \\varepsilon_{\\rho, A} [(\\lambda s \\mid f^X_{e_1})\\text{te1}]\\sigma\n= \\varepsilon_{\\rho_2, A_2} [f^X_{e_1}]\\sigma_2\n= \\varepsilon_{\\rho_2, A_2; x: \\text{te1}} [f]\\sigma_2[\\varepsilon_{\\rho, A} [e_1] \\sigma / x]\n= \\varepsilon_{\\rho_2, A_1; s} [f]\\sigma_1 \\uparrow \\text{WTV}(A_1; s)\n= \\varepsilon_{\\rho, A_1} [(\\lambda s \\mid f)\\text{te1}]\\sigma_1\n\\]\n\nRenaming bound variables should and indeed does not alter the meaning of an expression.\n\n**Theorem 5.3.6.** [Renaming a bound variable]\n\nFor all \\( \\rho \\in \\text{Tenv} ; A \\in \\text{Assumptions} ; \\sigma \\in \\text{ST}_{\\rho, A} ; \\text{te1, te} \\in \\text{Texp} ; x, y \\in \\text{Var} \\) and \\( e \\in \\text{Exp} \\):\n\nIf \n\\( \\vdash A \\triangleright \\text{te1} \\) \n\\( \\vdash A; x: \\text{te1} \\triangleright e : \\text{te} \\)\n\\( y \\in \\text{FV}(e) \\)\n\nThen \n\\( \\varepsilon_{\\rho, A} [(\\lambda x: \\text{te1} \\mid e)]\\sigma = \\varepsilon_{\\rho, A} [(\\lambda y: \\text{te1} \\mid e^X_y)]\\sigma \\)\n\nand \n\\( \\varepsilon_{\\rho, A} [(\\lambda s x: \\text{te1} \\mid e)]\\sigma = \\varepsilon_{\\rho, A} [(\\lambda s y: \\text{te1} \\mid e^X_y)]\\sigma \\)\n\n**Proof.** Assume (*) ,(**) and (***) .\n1. Let \\( D = \\mathcal{F}_{[\\text{tel}]} \\) and \\( d \\in D \\)\n\n2. Let \\( A_n \\in \\text{Assumptions} \\) and \\( \\sigma_n \\in \\text{ST}_{\\rho, A_n} \\), \\( 0 \\leq n \\leq 4 \\), be such that\n \\[\n \\begin{align*}\n A_1 &= A; x : \\text{tel} & \\sigma_1 &= \\sigma[d/x] \\\\\n A_2 &= A; y : \\text{tel} & \\sigma_2 &= \\sigma[d/y] \\\\\n A_3 &= A_2; x : \\text{tel} & \\sigma_3 &= \\sigma_2[\\mathcal{E}_{\\rho, A_2}[y]\\sigma_2 / x] \\\\\n A_4 &= A_1; y : \\text{tel} & \\sigma_4 &= \\sigma_1[d/y]\n \\end{align*}\n \\]\n\n3. \\( \\vdash A_1 \\triangleright \\text{tel} \\) \\hfill [(*)], ER11.2\n\n4. \\( \\vdash A_2 \\triangleright y : \\text{tel} \\) \\hfill [(*)], ER2\n\n5. \\( \\vdash A_4 \\triangleright e : \\text{te} \\) \\hfill [(**), (***)], (4), ER11.2\n\n6. \\( \\vdash A_3 \\triangleright e : \\text{te} \\) \\hfill [(5), ER12.2]\n\n7. \\[\n\\begin{align*}\n\\sigma_3 &= \\sigma_2[\\mathcal{E}_{\\rho, A_2}[y]\\sigma_2 / x] \\\\\n&= \\sigma_2[\\sigma_2(y) / x] \\\\\n&= \\sigma_2[d/x] \\\\\n&= \\sigma_1[d/y] \\\\\n&= \\sigma_4\n\\end{align*}\n\\]\n\n8. \\[\n\\begin{align*}\n\\mathcal{E}_{\\rho, A_2}[e^x_y]\\sigma_2 \\\\\n&= \\mathcal{E}_{\\rho, A_3}[e]\\sigma_3 \\\\\n&= \\mathcal{E}_{\\rho, A_4}[e]\\sigma_4 \\\\\n&= \\mathcal{E}_{\\rho, A_1}[e]\\sigma_1\n\\end{align*}\n\\]\n\n9. \\[\n\\begin{align*}\n\\mathcal{E}_{\\rho, A}[(\\lambda y : \\text{tel} | e^x_y)\\sigma] \\\\\n&= (\\lambda d \\in D | \\mathcal{E}_{\\rho, A_2}[e^x_y]\\sigma_2) \\hfill [\\text{def.} \\mathcal{E}] \\\\\n&= (\\lambda d \\in D | \\mathcal{E}_{\\rho, A_1}[e]\\sigma_1) \\hfill [(8)] \\\\\n&= \\mathcal{E}_{\\rho, A}[(\\lambda x : \\text{tel} | e)\\sigma] \\hfill [(2), \\text{def.} \\mathcal{E}]\n\\end{align*}\n\\]\n\nThe case of strict \\( \\lambda \\)-abstraction is proved similarly.\nCHAPTER 6\n\n6.SOUNDNESS OF REDUCTION\n\n6.1 Introduction.\n\nIn chapter 3 we have introduced a set of reduction rules for expressions. Furthermore, we have shown that for expressions \\( e_1 \\) and \\( e_2 \\) such that \\( e_1 \\rightarrow e_2 \\) their values \\( E_{\\rho,A}[e_1] \\sigma \\) and \\( E_{\\rho,A}[e_2] \\sigma \\) are members of the same domain \\( H[\\tau_A(e_1)] \\rho = H[\\tau_A(e_2)] \\rho \\). In this chapter we prove that the reduction rules of chapter 3 are sound, i.e. reducing an expression yields an expression with the same value. In order to prove this result we need some elementary properties.\n\nProperty 6.1.1. [strictness]\nFor all \\( A \\in \\text{Assumptions} ; \\rho \\in \\text{Tenv} ; \\sigma \\in \\text{ST}_{\\rho,A} ; \\text{te,te1} \\in \\text{Texp} \\) and \\( f \\in \\text{Exp} \\):\n\nIf \\( \\vdash A \\triangleright f : \\text{te} \\bigcirc \\text{te1} \\)\n\nThen \\( (E_{\\rho,A}[f] \\sigma) (\\uparrow H[\\text{te}] \\rho) = \\uparrow H[\\text{te1}] \\rho \\)\n\n\\( \\Box \\)\n\nProperty 6.1.2. [normal form]\nFor all \\( A \\in \\text{Assumptions} ; \\rho \\in \\text{Tenv} ; \\sigma \\in \\text{ST}_{\\rho,A} \\) and \\( e \\in \\text{Exp} \\):\n\nIf \\( e \\) is in normal form\n\nand \\( (\\forall x \\in \\text{WTV}(A) \\mid \\sigma(x) \\neq \\uparrow H[\\tau_A(x)] \\rho) \\)\n\nThen \\( E_{\\rho,A}[e] \\sigma \\neq \\uparrow H[\\tau_A(e)] \\rho \\).\n\n\\( \\Box \\)\n\n6.2 Soundness.\n\nTheorem 6.2.1. [soundness]\nFor all \\( A \\in \\text{Assumptions} ; \\rho \\in \\text{Tenv} ; \\sigma \\in \\text{ST}_{\\rho,A} \\) and \\( e_1,e_2 \\in \\text{WTE}(A) \\):\nIf \\( e_1 \\entails e_2 \\)\nand \\((\\forall x \\in \\text{WTV}(A) \\mid \\sigma(x) \\neq 1_{\\mathcal{F}[\\tau_A(x)]\\rho})\\)\nThen \\( \\mathcal{E}_{\\rho,A}[e_1]\\sigma = \\mathcal{E}_{\\rho,A}[e_2]\\sigma \\)\n\nProof. It is sufficient to prove the soundness of each of the rules \\( \\nu \\) thru \\( \\eta \\). Apart from rules \\( \\sigma_5, \\pi_4, \\pi_5, \\beta_1, \\beta_2 \\) and \\( \\beta_3 \\) this is a trivial exercise using definition 5.2.1.\n\nRule \\( \\sigma_5 \\): \\( (\\text{sums } f_1 f_2) \\rightarrow f \\), provided \\( x \\notin \\text{FV}(f) \\)\n\nwhere \\( f_1 = (\\lambda s x : t e_1 \\mid (\\text{apps} f (\\text{inls} x \\mid t e_2))) \\)\n\nand \\( f_2 = (\\lambda s x : t e_2 \\mid (\\text{apps} f (\\text{inrs} t e_1 \\mid x))) \\)\n\nAssume \\( x \\in \\text{FV}(f) \\)\n\n1. The lefthandside of \\( \\sigma_5 \\) is an element of \\( \\text{WTE}(A) \\) iff\n a) \\( \\vdash A \\triangleright t e_1, t e_2 \\)\n b) there exists a type expression \\( t e \\in \\text{Texp} \\) such that \\( \\vdash A \\triangleright f : t e_1 \\odot t e_2 \\Theta t e \\)\n\n2. Let \\( D_1 = \\mathcal{F}[t e_1]\\rho, D_2 = \\mathcal{F}[t e_2]\\rho \\) and \\( D = \\mathcal{F}[t e]\\rho \\). Moreover, let \\( A_1 = A; x : t e_1 \\) and \\( A_2 = A; x : t e_2 \\).\n\n3. Since \\( x \\in \\text{FV}(f) \\) it follows by (1), (***) and rule ER11.2\n that \\( \\vdash A_1 \\triangleright f : (t e_1 \\odot t e_2) \\Theta t e \\) and \\( \\vdash A_2 \\triangleright f : (t e_1 \\odot t e_2) \\Theta t e \\).\n Hence \\( \\mathcal{F}[\\tau_{A_1}(f)]\\rho = \\mathcal{F}[\\tau_{A_2}(f)]\\rho = \\mathcal{F}[\\tau_A(f)]\\rho \\).\n\n4. For \\( d \\in D_1 \\):\n \\[\n \\mathcal{E}_{\\rho,A_1}[(\\text{apps} f (\\text{inls} x \\mid t e_2))\\sigma[d/x]]\n = \\mathcal{E}_{\\rho,A_1}[f\\sigma[d/x]] (\\mathcal{E}_{\\rho,A_1}[(\\text{inls} x \\mid t e_2)]\\sigma[d/x])\n = \\mathcal{E}_{\\rho,A_1}[f\\sigma[d/x]] (<1,\\mathcal{E}_{\\rho,A_1}[x]\\sigma[d/x]>_{D_1 \\odot D_2})\n = \\mathcal{E}_{\\rho,A_1}[f\\sigma[d/x]] (<1,d>_{D_1 \\odot D_2})\n = \\mathcal{E}_{\\rho,A}[f\\sigma] (<1,d>_{D_1 \\odot D_2})\n \\]\n \\[[1a),(1b),(***)\\text{,thm5.3.4}]\nSimilarly one proves for $d \\in D_2$:\n\n\\[\n\\mathcal{E}_{\\rho, A_2}[(\\text{apps } f (\\text{inrs } t e \\mid x))] \\sigma[d/x]\n\\]\n\n\\[\n= \\mathcal{E}_{\\rho, A}[[f] \\sigma (\\langle 2, d \\rangle D_1 \\oplus D_2)]\n\\]\n\n5. \\[\n\\mathcal{E}_{\\rho, A}[[f1] \\sigma]\n\\]\n\n\\[\n= (\\lambda d \\in D_1 \\quad \\begin{array}{l}\n\\text{if } d = \\downarrow D_1 \\rightarrow \\downarrow D \\\\\n\\text{fi }\n\\end{array}\n\\]\n\n\\[\n\\text{d} \\neq \\downarrow D_1 \\rightarrow \\mathcal{E}_{\\rho, A}[[f] \\sigma (\\langle 1, d \\rangle D_1 \\oplus D_2)]\n\\]\n\n\\[\n\\quad \\begin{array}{l}\n\\text{fi }\n\\end{array}\n\\]\n\n\\[\n= (\\lambda d \\in D_1 \\mid \\mathcal{E}_{\\rho, A}[[f] \\sigma (\\langle 1, d \\rangle D_1 \\oplus D_2)])\n\\]\n\nSimilarly one proves that\n\n\\[\n\\mathcal{E}_{\\rho, A}[[f2] \\sigma] = (\\lambda d \\in D_2 \\mid \\mathcal{E}_{\\rho, A}[[f] \\sigma (\\langle 2, d \\rangle D_1 \\oplus D_2)])\n\\]\n\n6. \\[\n\\mathcal{E}_{\\rho, A}[(\\text{sums } f1 f2)] \\sigma\n\\]\n\n\\[\n= (\\lambda d \\in D_1 \\oplus D_2 \\quad \\begin{array}{l}\n\\text{if } d = \\langle 1, d_1 \\rangle D_1 \\oplus D_2 \\rightarrow (\\mathcal{E}_{\\rho, A}[[f1] \\sigma) (d_1) \\\\\n\\text{fi }\n\\end{array}\n\\]\n\n\\[\n\\text{d} = \\langle 2, d_2 \\rangle D_1 \\oplus D_2 \\rightarrow (\\mathcal{E}_{\\rho, A}[[f2] \\sigma) (d_2)\n\\]\n\n\\[\n\\quad \\begin{array}{l}\n\\text{fi }\n\\end{array}\n\\]\n\\[ \\lambda d \\in D_1 \\otimes D_2 \\]\n\n\\[ \\text{if } d = \\langle d_1 \\rangle_{D_1 \\otimes D_2} \\rightarrow \\mathcal{E}_{\\rho, A}[f] \\sigma (\\langle d_1 \\rangle_{D_1 \\otimes D_2}) \\]\n\n\\[ \\bigoplus d = \\langle d_2 \\rangle_{D_1 \\otimes D_2} \\rightarrow \\mathcal{E}_{\\rho, A}[f] \\sigma (\\langle d_2 \\rangle_{D_1 \\otimes D_2}) \\]\n\n\\[ \\text{fi} \\]\n\n\\[ \\lambda d \\in D_1 \\otimes D_2 \\mid \\mathcal{E}_{\\rho, A}[f] \\sigma (d) \\]\n\n\\[ \\mathcal{E}_{\\rho, A}[f] \\sigma \\]\n\nRule \\( \\pi_4 : (\\text{prols (prods e1 e2)}) \\rightarrow e1 \\), provided \\( e2 \\) in normal form.\n\nAssume \\( e2 \\) is in normal form.\n\n\\[ (\\forall x \\in \\text{WTW}(A) \\mid \\sigma(x) \\neq \\tau_{\\rho}[A](e)) \\]\n\n\\[ (\\ast) \\]\n\n\\[ (\\ast\\ast) \\]\n\n1. Let \\( D_1 = \\tau_{\\rho}[A](e1) \\) and \\( D_2 = \\tau_{\\rho}[A](e2) \\).\n\n2. \\( \\mathcal{E}_{\\rho, A}[(\\text{prols (prods e1 e2)})] \\sigma \\)\n\n\\[ \\psi_i(\\langle \\mathcal{E}_{\\rho, A}[e1] \\sigma, \\mathcal{E}_{\\rho, A}[e2] \\sigma \\rangle_{D_1 \\otimes D_2}) \\]\n\n\\[ \\text{if } \\mathcal{E}_{\\rho, A}[e2] \\sigma = \\tau_{D_2} \\rightarrow \\tau_{D_1} \\]\n\n\\[ \\bigoplus \\mathcal{E}_{\\rho, A}[e2] \\sigma = \\tau_{D_2} \\rightarrow \\mathcal{E}_{\\rho, A}[e1] \\sigma \\]\n\n\\[ \\text{fi} \\]\n\n\\[ \\mathcal{E}_{\\rho, A}[e1] \\sigma \\]\n\n\\[ \\ast, \\ast\\ast \\text{, prop.6.1.2} \\]\n\nSimilarly one proves the soundness of rule \\( \\pi_5 \\).\n\nRules \\( \\beta_1, \\beta_2, \\beta_3 \\):\n\nThe soundness of rules \\( \\beta_1 \\) and \\( \\beta_2 \\) follows from a simple computation using theorem 5.3.2.\n\nThe soundness of rule \\( \\beta_3 \\) follows from theorem 5.3.1.\n\n\\[ \\square \\]\nCHAPTER 7\n\n7.A TYPED FIXED POINT COMBINATOR\n\n7.1 Syntax.\n\nIn the type free lambda calculus every term can be considered as a function. Moreover, every term (function) has a fixed point which can be computed using a fixed point combinator. The most well known fixed point combinator in the type free lambda calculus is the Curry combinator\n\n\\[ \\mu = (\\lambda f \\mid (\\lambda x \\mid f(xx)) (\\lambda x \\mid f(xx)) ) \\]\n\nA simple calculation shows that for every term \\( g \\) the terms \\( \\mu g \\) and \\( g(\\mu g) \\) are convertible; so \\( \\mu g \\) can be considered as a fixed point of \\( g \\). It can be shown that in the \\( D_\\infty \\) model of the type free lambda calculus \\( \\mu \\) corresponds to the least fixed point operator, see for instance Wadsworth [Wa76].\n\nIn this chapter we show that similar results hold for the typed language described in this report. Let \\( te \\) be an arbitrary type expression. In this section we shall describe an expression \\( (\\mu \\mid te) \\) with type \\( (te \\rightarrow te) \\rightarrow te \\), which can be considered as a typed version of the Curry combinator. In \\( (\\mu \\mid te) \\) a recursively defined type will be used. Some properties associated with the corresponding domain (found by the inverse limit construction) are given in section 7.2. Finally in section 7.3 we show that in the appropriate domain \\( (\\mu \\mid te) \\) corresponds to the least fixed point operator.\n\nIn this chapter we use the following abbreviations\n\n\\[\nw = v(\\Lambda t \\mid t \\rightarrow te)\n\\]\n\nwhere \\( t \\) is the first type variable such that \\( t \\notin FTV(te) \\) and\n\n\\[\ng = (\\lambda x:w \\mid (appl f (appl (intro w \\mid x) x)) ) .\n\\]\n\nA typed version of the Curry combinator is then given by\n\n\\[\n(\\mu \\mid te) = (f : te \\rightarrow te \\mid (appl g (elim w \\mid g)) ) .\n\\]\n\nIt is an elementary exercise to show that the following type inference rule holds\nThe following theorem states that \\((\\mu \\mid \\text{te})\\) is a syntactic fixed point combinator.\n\n**Theorem 7.1.4.**\n\nLet \\(f : \\text{te} \\rightarrow \\text{te}\\). Then \\((\\text{appl} (\\mu \\mid \\text{te}) f)\\) and \\((\\text{appl} f (\\text{appl} (\\mu \\mid \\text{te}) f))\\) have a common reduct.\n\n**Proof.** The theorem is easily proved by the following computations.\n\n\\[\n(\\text{appl} (\\mu \\mid \\text{te}) f) \\\\\n\\Rightarrow (\\text{appl} g (\\text{elim} w \\mid g)) \\quad [\\beta_1] \\\\\n\\Rightarrow (\\lambda x : w \\mid (\\text{appl} f (\\text{appl} (\\text{intro} w \\mid x)) \\,(\\text{elim} w \\mid g)) \\quad [(7.1.2)] \\\\\n= (\\text{appl} f (\\text{appl} (\\text{intro} w \\mid (\\text{elim} w \\mid g)) \\,(\\text{elim} w \\mid g))) \\quad [\\beta_1] \\\\\n\\Rightarrow (\\text{appl} f (\\text{appl} g (\\text{elim} w \\mid g))) \\quad [e_2]\n\\]\n\nAlso\n\n\\[\n(\\text{appl} f (\\text{appl} (\\mu \\mid \\text{te}) f)) \\\\\n\\Rightarrow (\\text{appl} f (\\text{appl} g (\\text{elim} w \\mid g))) \\quad [\\beta_1]\n\\]\n\nwhich proves the theorem.\n\n\\(\\Box\\)\n\nNote that, although \\((\\text{appl} (\\mu \\mid \\text{te}) f)\\) and \\((\\text{appl} f (\\text{appl} (\\mu \\mid \\text{te}) f))\\) have a common reduct, it is not possible to reduce one of these terms to the other. The same property holds for the untyped Curry combinator. For the untyped lambda calculus there exists another fixed point combinator, the Turing combinator \\(\\mu'\\), such that \\(\\mu' f\\) reduces to \\(f(\\mu' f)\\). A typed version of the Turing combinator, with similar properties as described in this report, can also be given, see for instance Struik[St88].\n7.2. Technical results.\n\nIn the construction of \\((\\mu|te)\\) we used the recursive type \\(w = v(\\Lambda t|t \\rightarrow te)\\). In a type environment \\(\\rho\\) the corresponding domain \\(W\\) is obtained in the following way. Let the functor \\(F : C \\rightarrow C\\) be given by\n\n\\[\nF = \\text{abstr}_t \\mathcal{F}[t \\rightarrow te](\\rho)\n\\]\n\nThen, following the semantics of type expressions as described in section 4, we get\n\n\\[\nW = \\mathcal{F}[v(\\Lambda t|t \\rightarrow te)]\\rho = \\text{IFP}(F).\n\\] \n\n(7.2.1)\n\nA simple computation (using the definition of abstr given in section 4.1) yields that\n\n\\[\nF = \\text{FS} \\circ <I, C_B> : C \\rightarrow C\n\\]\n\nwhere \\(I, C_B : C \\rightarrow C\\) are respectively the identity functor and the constant functor corresponding to the domain \\(B = \\mathcal{F}[te]\\). Recall that in the category \\(C\\) (= \\(\\text{CPO}_{\\text{pr}}\\)) a morphism \\(\\alpha \\in \\text{Hom}(A_1, A_2)\\) is a pair \\(\\alpha = (\\alpha^L, \\alpha^R)\\), where \\(\\alpha^L : A_1 \\rightarrow A_2\\) is an embedding and \\(\\alpha^R : A_2 \\rightarrow A_1\\) is a projection, i.e.\n\n\\[\n\\alpha^L \\circ \\alpha^R \\subseteq \\text{id}_{A_2} \\quad \\text{and} \\quad \\alpha^R \\circ \\alpha^L = \\text{id}_{A_1}\n\\] \n\n(7.2.2)\n\nIf \\(\\alpha\\) is an isomorphism, then in the first relation equality holds and\n\n\\[\n(\\alpha^{-1})^L = \\alpha^R, \\quad (\\alpha^{-1})^R = \\alpha^L.\n\\]\n\nThe composition of the morphisms \\(\\alpha = (\\alpha^L, \\alpha^R) \\in \\text{Hom}(A_1, A_2)\\) and \\(\\beta = (\\beta^L, \\beta^R) \\in \\text{Hom}(A_2, A_3)\\) is given by\n\n\\[\n\\beta \\circ \\alpha = (\\beta^L \\circ \\alpha^L, \\alpha^R \\circ \\alpha^R).\n\\]\n\nFrom the definition of the function space functor \\(\\text{FS}\\) (see for instance [BH88], where this functor is called \\(A\\)) it follows that (recall \\(B = \\mathcal{F}[te]\\rho\\))\n\n- if \\(A \\in \\text{obj}(C)\\), then \\(F(A) = [A \\rightarrow B]\\),\n- if \\(\\alpha \\in \\text{Hom}(A_1, A_2)\\), then \\(F(\\alpha) \\in \\text{Hom}( [A_1 \\rightarrow B], [A_2 \\rightarrow B] )\\) is defined by\n\n\\[\nF(\\alpha)^L(\\xi) = \\xi \\circ \\alpha^R \\quad \\text{for} \\quad \\xi \\in [A_1 \\rightarrow B],\n\\] \n\n(7.2.3)\nThe object $W$ is constructed in the following way. Let $D_0$ be the initial object in the category $C$, i.e. $D_0$ is the one point c.p.o. Let $D_k = F^k(D_0)$ for $k \\geq 1$. Since $D_0$ is initial, there exists a unique morphism $\\psi_0 \\in \\text{Hom}(D_0, D_1)$. Let $\\psi_k = F^k(\\psi_0)$ for $k \\geq 1$. Then $\\Delta = \\langle (D_i, \\psi_i) \\rangle_{i=0}^{\\infty}$ is an $\\omega$–chain in $C$. Since $C$ is an $\\omega$–category this $\\omega$–chain has a colimit $(W, \\alpha)$. This defines the (an) object $W$. To see that $W$ is a fixed point of the functor $F$, we consider the $\\omega$–chain $\\Delta' = \\langle (F(D_i), F(\\psi_i)) \\rangle_{i=0}^{\\infty} = \\langle (D_{i+1}, \\psi_{i+1}) \\rangle_{i=0}^{\\infty}$. Since $F$ is an $\\omega$–continuous functor it preserves colimits. So $(F(W), F(\\alpha))$ (where $F(\\alpha)$ stands for $\\langle F(\\alpha_i) \\rangle_{i=0}^{\\infty}$) is a colimit of the $\\omega$–chain $\\Delta'$. Apart from the first element of $\\Delta$, the chains $\\Delta$ and $\\Delta'$ are identical. Thus $(W, \\alpha)$ and $(F(W), F(\\alpha))$ are both colimits of the same $\\omega$–chain, which implies that there exists an isomorphism $\\beta \\in \\text{Hom}(F(W), W)$. The situation may be elucidated by the following figure.\n\nNow the following properties hold (see for instance Smyth and Plotkin[SP82] or Bos and Hemerik [BH88]).\n\n\\[\n\\alpha_k^L \\circ \\alpha_k^R \\subseteq \\text{id}_W \\tag{7.2.4}\n\\]\n\\[\n\\alpha_k^L \\circ \\alpha_k^R \\subseteq \\text{id}_{D_k} \\tag{7.2.5}\n\\]\n\\[\n\\beta^{-1} \\circ \\alpha_k^{k+1} = F(\\alpha_k) \\tag{7.2.6}\n\\]\n\\[\n\\beta \\circ F(\\alpha_k) = \\alpha_k^{k+1} \\tag{7.2.7}\n\\]\nCHAPTER 7\n\n\\[\n\\bigcup_{k=0}^{\\infty} \\alpha_k^L \\circ \\alpha_k^R = \\text{id}_W \\tag{7.2.8}\n\\]\n\nDefine the mapping \\( P_k : W \\rightarrow W \\) by \\( P_k = \\alpha_k^L \\circ \\alpha_k^R \\). Then (7.2.4) and (7.2.8) can be written as\n\n\\[\nP_k \\subseteq \\text{id}_W \\tag{7.2.9}\n\\]\n\nand\n\n\\[\n\\bigcup_{k=0}^{\\infty} P_k = \\text{id}_W \\tag{7.2.10}\n\\]\n\nSince \\( D_0 \\) is the one–point c.p.o. and \\( \\alpha_0^L \\) is strict, we have\n\n\\[\nP_0(x) = \\bot_W \\quad \\text{for all } x \\in W \\tag{7.2.11}\n\\]\n\nIn the remainder of this section we give some technical lemmas, which will be used in section 7.3.\n\nLemma 7.2.12.\n\nIf \\( \\ell \\geq k \\geq 0 \\) then \\( \\alpha_k^R \\circ P_\\ell = \\alpha_k^R \\) and \\( P_\\ell \\circ \\alpha_k^L = \\alpha_k^L \\).\n\nProof. We prove the first relation for fixed \\( \\ell \\) by induction with respect to \\( k \\). If \\( k = \\ell \\) the result follows from (7.2.5). Next suppose \\( \\alpha_k^R \\circ P_\\ell = \\alpha_k^R \\) and \\( \\ell \\geq k \\geq 1 \\). Since \\((W,\\alpha)\\) is a cocone for \\( I \\), we have \\( \\alpha_{k-1} = \\alpha_k \\circ \\psi_{k-1} \\), so \\( \\alpha_{k-1}^R = \\psi_{k-1}^R \\circ \\alpha_k^R \\). Then using the induction hypothesis, we get\n\n\\[\n\\alpha_{k-1}^R \\circ P_\\ell = \\psi_{k-1}^R \\circ \\alpha_k^R \\circ P_\\ell = \\psi_{k-1}^R \\circ \\alpha_k^R \\circ \\alpha_k^L = \\alpha_{k-1}^R .\n\\]\n\nThe second part of the lemma can be proved in a similar way.\n\nLemma 7.2.13.\n\nIf \\( k \\geq 0 \\) and \\( \\ell \\geq 0 \\) then \\( P_k \\circ P_\\ell = P_{\\min(k, \\ell)} \\).\n\nProof. The lemma follows immediately from the definition of \\( P_k \\) and lemma 7.2.12.\n\n\\[\n\\square\n\\]\n\n66\nNote that if \\( y \\in W \\), then \\( \\beta^R(y) \\in F(W) = [W \\rightarrow B] \\). In the case that \\( y \\in P_{k+1}(W) \\) the mapping \\( \\beta^R(y) : [W \\rightarrow B] \\) has a special property.\n\n**Lemma 7.2.14.**\n\nLet \\( x \\in W \\) and \\( \\ell \\geq k \\geq 0 \\). Then\n\n\\[\n\\beta^R(P_{k+1}(x)) = \\beta^R(P_{k+1}(x)) \\circ P_\\ell. ;\n\\]\n\n**Proof.** The lemma follows from the following computation.\n\n\\[\n\\begin{align*}\n\\beta^R(P_{k+1}(x)) &= F(\\alpha_{k+1}^R) (\\alpha_{k+1}^R(x)) \\\\\n&= (\\alpha^R_{k+1}(x)) \\circ \\alpha_k^R \\\\\n&= (\\alpha^R_{k+1}(x)) \\circ \\alpha_k^R \\circ P_\\ell.\n\\end{align*}\n\\]\n\n\\[\\square\\]\n\n**7.3. Semantics.**\n\nWe now show that the semantics of \\( (\\mu \\triangleright te) \\) is the least fixed point operator in the appropriate c.p.o. The computation given here, is similar to the computation of the semantics of the untyped Curry fixed point combinator as given in Wadsworth [Wa76].\n\nSuppose that \\( \\vdash A \\triangleright te \\) and let \\( \\rho \\in Tenv \\). We introduce the following abbreviations:\n\n\\[\n\\begin{align*}\nw &= \\nu(\\Lambda t \\mid t \\rightarrow te), \\\\\ng &= (\\lambda x:w \\mid (\\text{appl } f (\\text{appl } (\\text{intro } w \\mid x) x))) , \\\\\nW &= \\mathcal{F}[\\nu(\\Lambda t \\mid t \\rightarrow te)]\\rho , \\\\\nB &= \\mathcal{F}[te] \\rho , \\\\\n\\chi &= \\varepsilon_{\\rho,A_1}[g]_{\\sigma[\\phi/f]} \\quad \\text{where } A_1 = A;f:te \\rightarrow te\n\\end{align*}\n\\]\nCHAPTER 7\n\nFrom the definition of the semantics of expressions, see [def. 5.2.1 case 7], it follows that\n\n$$\\chi = E_{\\rho, A}[[\\varepsilon]]_\\sigma[\\phi/f] = (\\lambda d \\in W \\mid \\phi( (\\beta^R(d)) d))$$ \\hspace{1cm} (7.3.1)\n\nwhere $\\beta$ is the isomorphism between $F(W) = [W \\rightarrow B]$ and $W$. From (7.1.3) we get\n\n$$E_{\\rho, A}[[\\mu|te]]_\\sigma = (\\lambda \\phi \\in [B \\rightarrow B] \\mid \\chi(\\beta^L(\\chi)))$$ \\hspace{1cm} (7.3.2)\n\nThe following theorem shows that $E_{\\rho, A}[[\\mu|te]]_\\sigma$ is a fixed point operator for the domain $B$.\n\nTheorem 7.3.3.\n\nLet $\\phi \\in [B \\rightarrow B]$. Then for all states $\\sigma \\in ST_{\\rho, A}$\n\n$$(E_{\\rho, A}[[\\mu|te]]_\\sigma) \\phi = \\phi((E_{\\rho, A}[[\\mu|te]]_\\sigma) \\phi)$$\n\nProof. The theorem follows from the following computation.\n\n$$(E_{\\rho, A}[[\\mu|te]]_\\sigma) \\phi$$\n$$= \\chi(\\beta^L(\\chi))$$ \\hspace{1cm} (7.3.2)\n$$= \\phi((\\beta^R(\\beta^L(\\chi))) (\\beta^L(\\chi)))$$ \\hspace{1cm} (7.3.1)\n$$= \\phi(\\chi(\\beta^L(\\chi)))$$ \\hspace{1cm} (7.2.2)\n$$= \\phi((E_{\\rho, A}[[\\mu|te]]_\\sigma) \\phi)$$ \\hspace{1cm} (7.3.2)\n\n$\\square$\n\nSince\n\n$$\\mu_B = (\\lambda \\phi \\in [B \\rightarrow B] \\mid \\bigcup_{k=0}^{\\infty} \\phi^k(\\mu_B))$$ \\hspace{1cm} (7.3.4)\n\nis the least fixed point operator in the c.p.o. $B$, we now have\n\n$$\\mu_B \\subseteq E_{\\rho, A}[[\\mu|te]]_\\sigma.$$ \\hspace{1cm} (7.3.5)\n\nThe following theorem shows that in (7.3.5) equality holds.\nTheorem 7.3.6.\nFor all states \\( \\sigma \\in \\text{ST}_{\\rho,A} \\)\n\n\\[\n\\mathcal{E}_{\\rho,A}[(\\mu|\\text{te})]\\sigma = \\mu_B.\n\\]\n\nProof. We first show by induction with respect to \\( k \\) that for \\( k \\geq 0 \\)\n\n\\[\n\\chi(P_k(\\beta^L(\\chi))) \\subseteq \\phi^{k+1}(\\mu_B) \\quad (7.3.7)\n\\]\n\n- Induction basis, \\( k = 0 \\). Then\n\n\\[\n\\begin{align*}\n\\chi(P_0(\\beta^L(\\chi))) &= \\chi(\\iota_W) \\\\\n&= \\phi(\\beta^R(\\iota_W)) \\iota_W \\\\\n&= \\phi(\\iota_B). \\\\\n\\end{align*}\n\\]\n\n[\\( \\beta^R \\) is strict]\n\n- Induction step. Suppose (7.3.7) holds. Then\n\n\\[\n\\begin{align*}\n\\chi(P_{k+1}(\\beta^L(\\chi))) &= \\phi(\\beta^R(P_{k+1}(\\beta^L(\\chi))) (P_{k+1}(\\beta^L(\\chi))) \\\\\n&= \\phi(\\beta^R(P_{k+1}(\\beta^L(\\chi))) \\circ P_{k+1}(\\beta^L(\\chi))) \\quad \\text{[lemma 7.2.14 with } \\ell = k \\text{ and } \\chi = \\beta^L(\\chi)] \\\\\n&= \\phi(\\beta^R(P_{k+1}(\\beta^L(\\chi))) (P_k(\\beta^L(\\chi))) \\quad \\text{[lemma 7.2.13]} \\\\\n&= \\phi(\\chi(P_k(\\beta^L(\\chi))) \\\\\n&\\subseteq \\phi(\\phi^{k+1}(\\iota_B)). \\\\\n\\end{align*}\n\\]\n\n[\\( \\beta^R \\) and \\( \\phi \\) are monotonic, (7.2.2)]\n\nThis proves (7.3.7) for all \\( k \\geq 0 \\). The theorem now follows from (7.3.5) and the following computation.\n\n\\[\n\\begin{align*}\n\\mathcal{E}_{\\rho,A}[(\\mu|\\text{te})]\\sigma &= (\\lambda \\phi \\in [B \\rightarrow B] | \\chi(\\bigcup_{k=0}^{\\infty} P_k(\\beta^L(\\chi)))) \\\\\n&= (7.3.2),(7.2.10)\n\\end{align*}\n\\]\n= \\langle \\forall \\phi \\in \\mathbb{B} \\mid \\bigcup_{k=0}^{\\infty} (\\chi (P_k(\\beta^L(\\chi)))) \\rangle \\tag{7.3.7} \\]\n\nThus we have shown that the semantics of $(\\mu \\mid te)$ is the least fixed point operator in the domain $\\mathbb{B}$ corresponding to the type expression $te$. This result means that it is not necessary to add recursion explicitly to the language given in chapters 1 and 2. Recursion can be performed using the typed fixed point combinator $(\\mu \\mid te)$, which can be written in terms of the already defined language. Note that the presence of recursively defined types is essential for the construction of $(\\mu \\mid te)$. \n\nREFERENCES\n\n\nREFERENCES\n\n\nIn this series appeared:\n\n<table>\n<thead>\n<tr>\n<th>No.</th>\n<th>Author(s)</th>\n<th>Title</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>85/01</td>\n<td>R.H. Mak</td>\n<td>The formal specification and derivation of CMOS-circuits</td>\n</tr>\n<tr>\n<td>85/02</td>\n<td>W.M.C.J. van Overveld</td>\n<td>On arithmetic operations with M-out-of-N-codes</td>\n</tr>\n<tr>\n<td>85/03</td>\n<td>W.J.M. Lemmens</td>\n<td>Use of a computer for evaluation of flow films</td>\n</tr>\n<tr>\n<td>85/04</td>\n<td>T. Verhoeff</td>\n<td>Delay insensitive directed trace structures satisfy the foam rubber wrapper postulate</td>\n</tr>\n<tr>\n<td></td>\n<td>H.M.J.L. Schols</td>\n<td></td>\n</tr>\n<tr>\n<td>86/01</td>\n<td>R. Koymans</td>\n<td>Specifying message passing and real-time systems</td>\n</tr>\n<tr>\n<td>86/02</td>\n<td>G.A. Bussing, K.M. van Hee, M. Voorhoeve</td>\n<td>ELISA, A language for formal specifications of information systems</td>\n</tr>\n<tr>\n<td>86/03</td>\n<td>Rob Hoogerwoord</td>\n<td>Some reflections on the implementation of trace structures</td>\n</tr>\n<tr>\n<td>86/04</td>\n<td>G.J. Houben, J. Paredaens, K.M. van Hee</td>\n<td>The partition of an information system in several parallel systems</td>\n</tr>\n<tr>\n<td>86/05</td>\n<td>Jan L.G. Dietz, Kees M. van Hee</td>\n<td>A framework for the conceptual modeling of discrete dynamic systems</td>\n</tr>\n<tr>\n<td>86/06</td>\n<td>Tom Verhoeff</td>\n<td>Nondeterminism and divergence created by concealment in CSP</td>\n</tr>\n<tr>\n<td>86/07</td>\n<td>R. Gerth, L. Shira</td>\n<td>On proving communication closedness of distributed layers</td>\n</tr>\n<tr>\n<td>86/09</td>\n<td>C. Huizing, R. Gerth, W.P. de Roever</td>\n<td>Full abstraction of a real-time denotational semantics for an OCCAM-like language</td>\n</tr>\n<tr>\n<td>86/10</td>\n<td>J. Hooman</td>\n<td>A compositional proof theory for real-time distributed message passing</td>\n</tr>\n<tr>\n<td>86/11</td>\n<td>W.P. de Roever</td>\n<td>Questions to Robin Milner - A responder's commentary (IFIP86)</td>\n</tr>\n<tr>\n<td>86/12</td>\n<td>A. Boucher, R. Gerth</td>\n<td>A timed failures model for extended communicating processes</td>\n</tr>\n</tbody>\n</table>\nProving monitors revisited: a first step towards verifying object oriented systems (Fund. Informatica IX-4)\n\nSpecifying passing systems requires extending temporal logic\n\nOn the existence of sound and complete axiomatizations of the monitor concept\n\nFederatieve Databases\n\nA formal approach to distributed information systems\n\nDelay-insensitive codes - An overview\n\nEnforcing non-determinism via linear time temporal logic specification.\n\nTemporele logica specificatie van message passing en real-time systemen (in Dutch).\n\nSpecifying message passing and real-time systems with real-time temporal logic.\n\nThe maximum number of states after projection.\n\nLanguage extensions to study structures for raster graphics.\n\nThree families of maximally nondeterministic automata.\n\nEldorado ins and outs. Specifications of a data base management toolkit according to the functional model.\n\nOR and AI approaches to decision support systems.\n\nPlaying with patterns, searching for strings.\n\nA compositional proof system for an occam-like real-time language\n87/15 C. Huizing\n R. Gerth\n W.P. de Roever\nA compositional semantics for statecharts\n\n87/16 H.M.M. ten Eikelder\n J.C.F. Wilmont\nNormal forms for a class of formulas\n\n87/17 K.M. van Hee\n G.-J.Houben\n J.L.G. Dietz\nModelling of discrete dynamic systems\n framework and examples\n\n87/18 C.W.A.M. van Overveld\nAn integer algorithm for rendering curved\n surfaces\n\n87/19 A.J.Seebregts\nOptimalisering van file allocatie in\n gedistribueerde database systemen\n\n87/20 G.J. Houben\n J. Paredaens\nThe R^2-Algebra: An extension of an\n algebra for nested relations\n\n87/21 R. Gerth\n M. Codish\n Y. Lichtenstein\n E. Shapiro\nFully abstract denotational semantics\n for concurrent PROLOG\n\n88/01 T. Verhoeff\nA Parallel Program That Generates the\n Möbius Sequence\n\n88/02 K.M. van Hee\n G.J. Houben\n L.J. Somers\n M. Voorhoeve\nExecutable Specification for Information\n Systems\n\n88/03 T. Verhoeff\nSettling a Question about Pythagorean Triples\n\n88/04 G.J. Houben\n J.Paredaens\n D.Tahon\nThe Nested Relational Algebra: A Tool to handle\n Structured Information\n\n88/05 K.M. van Hee\n G.J. Houben\n L.J. Somers\n M. Voorhoeve\nExecutable Specifications for Information Systems\n\n88/06 H.M.J.L. Schols\nNotes on Delay-Insensitive Communication\n\n88/07 C. Huizing\n R. Gerth\n W.P. de Roever\nModelling Statecharts behaviour in a fully\n abstract way\n\n88/08 K.M. van Hee\n G.J. Houben\n L.J. Somers\n M. Voorhoeve\nA Formal model for System Specification\n\n88/09 A.T.M. Aerts\n K.M. van Hee\nA Tutorial for Data Modelling\n88/10 J.C. Ebergen A Formal Approach to Designing Delay Insensitive Circuits\n88/11 G.J. Houben, J.Paredaens A graphical interface formalism: specifying nested relational databases\n88/12 A.E. Eiben Abstract theory of planning\n88/13 A. Bijlsma A unified approach to sequences, bags, and trees\n88/14 H.M.M. ten Eikelder, R.H. Mak Language theory of a lambda-calculus with recursive types\n88/15 R. Bos, C. Hemerik An introduction to the category theoretic solution of recursive domain equations\n88/16 C. Hemerik, J.P. Katoen Bottom-up tree acceptors\n88/17 K.M. van Hee, G.J. Houben, L.J. Somers, M. Voorhoeve Executable specifications for discrete event systems"}}},{"rowIdx":93,"cells":{"id":{"kind":"string","value":"4064e34f1131b673b4a33a98165031070bc0831b"},"text":{"kind":"string","value":"\nJuly 2010\n\nAmericas Headquarters\nCisco Systems, Inc.\n170 West Tasman Drive\nSan Jose, CA 95134-1706\nUSA\nhttp://www.cisco.com\nTel: 408 526-4000\n800 553-NETS (6387)\nFax: 408 527-0883\n\nText Part Number: OL-23043-01\nThe Cisco implementation of TCP header compression is an adaptation of a program developed by the University of California, Berkeley (UCB) as part of UCB's public domain version of the UNIX operating system. All rights reserved. Copyright © 1981, Regents of the University of California.\n\nNotwithstanding any other warranty herein, all document files and software of these suppliers are provided \"as is\" with all faults. Cisco and the above-named suppliers disclaim all warranties, expressed or implied, including, without limitation, those of merchantability, fitness for a particular purpose and noninfringement or arising from a course of dealing, usage, or trade practice.\n\nIn no event shall Cisco or its suppliers be liable for any indirect, special, consequential, or incidental damages, including, without limitation, lost profits or loss or damage to data arising out of the use or inability to use this manual, even if Cisco or its suppliers have been advised of the possibility of such damages.\n\nCisco and the Cisco Logo are trademarks of Cisco Systems, Inc. and/or its affiliates in the U.S. and other countries. A listing of Cisco's trademarks can be found at www.cisco.com/go/trademarks. Third party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1005R)\n\nCopyright © 2010 Cisco Systems, Inc. All rights reserved.\n## Preface\n\n- Audience\n- Organization\n- Conventions\n- Obtaining Documentation and Submitting a Service Request\n- Document Change History\n\n## CONTENTS\n\n### CHAPTER 1\n\n### CORBA Architecture and Application Programming Interface\n\n- CORBA Adapter Architecture 1-1\n- Interface 1-2\n- XML Interface 1-3\n- Batch Data Retrieval (Paging) 1-3\n- Sessions and Transactions 1-3\n- ORB Specifications 1-3\n - Compiler Tools 1-4\n - ORB Deployment 1-4\n - NameService 1-10\n- BTS 10200 Softswitch IDL 1-10\n- BTS 10200 API 1-11\n - BTS 10200 Security API 1-11\n - Login 1-11\n - Logout 1-12\n - BTS 10200 Provisioning API 1-12\n - getCommandDoc 1-13\n - request 1-13\n- CORBA Session Manageability Feature 1-13\n - Software Developer’s Kit 1-14\n - CORBA Interface Servant 1-14\n - Session and System Manager 1-14\n - User Security Manager 1-15\n - Command Line Interface Reference 1-15\n - EMS Session Control Policy Table 1-15\n - User Table 1-15\nSession Has Been Removed By Session Control Policy (OSS 16) 5-12\nSession Removed But No OOS (16) Returned 5-13\nSession Has Been Removed (OSS 17) 5-13\nInterface Is Active and Operational (OSS 19) 5-13\nInterface Is Not Started or Not Operational (OSS 20) 5-13\nResource Reset (OSS 21) 5-13\nError Messages 5-13\nAlarms 5-14\n OSS (12) 5-14\n OSS (14) 5-14\n OSS (16) 5-15\n OSS (17) 5-15\n OSS (19) 5-16\n OSS (20) 5-16\n OSS (21) 5-17\n\nAPPENDIX A\nSubscriber Noun and Add Verb A-1\nForeign Key Relationships A-8\n\nAPPENDIX B\nXML Request Batch File B-1\nCLI to CORBA XML Transaction B-4\n\nAPPENDIX C\nBTSxsdk Java Capabilities C-1\n SDK C-1\n Java Classes C-2\n CORBA Interface Servant C-2\n Extensions C-2\n Dual Mode Operations C-2\n Prerequisites C-2\n OpenORB Settings C-3\n Build the BTSxsdk C-3\n Run BTSxsdk C-4\nPreface\n\nRevised: July 2010, OL-23043-01\n\nThis document is the *Cisco BTS 10200 Softswitch CORBA Adapter Interface Specification Programmer’s Guide, Release 7.0.*\n\n**Audience**\n\nThis document is designed for intermediate and advanced CORBA programmers. It presumes an intermediate or higher level of CORBA programming familiarity.\n\n**Organization**\n\nThis document is divided into the following chapters and appendixes:\n\n- **Chapter 1, “CORBA Architecture and Application Programming Interface”**—This chapter describes the CORBA adapter (CAD), which provides a machine-to-machine interface (MMI) over Common Object Request Broker Architecture (CORBA).\n- **Chapter 2, “Extensible Markup Language Processing”**—This chapter describes the Extensible Markup Language (XML) process in the Common Object Request Broker Architecture (CORBA) adapter.\n- **Chapter 3, “Proxy”**—This chapter describes an extension in the CORBA Software Developer’s kit (SDK) package that allows several new features to be integrated into the client application.\n- **Chapter 4, “Secure Socket Layer Support”**—This chapter describes the Common Object Request Broker Architecture (CORBA) Secure Socket Layer (SSL) support.\n- **Chapter 5, “Troubleshooting”**—This chapter describes basic cadexceptions, debug actions, and network configuration procedures.\n- **Appendix A, “XML Description Documents”**—This appendix provides examples of the XML description documents.\n- **Appendix B, “XML Test Drivers”**—This appendix describes the XML test drivers.\n- **Appendix C, “Sample CORBA Client Package (BTSxsd) Implementation”**—This appendix provides a sample implementation of a CORBA Client Package (BTSxsd).\nConventions\n\nThis document uses the following conventions:\n\n<table>\n<thead>\n<tr>\n<th>Note</th>\n<th>Means reader take note. Notes contain helpful suggestions or references to material not covered in the manual.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Caution</td>\n<td>Means reader be careful. In this situation, you might do something that could result in equipment damage or loss of data.</td>\n</tr>\n</tbody>\n</table>\n\nObtaining Documentation and Submitting a Service Request\n\nFor information on obtaining documentation, submitting a service request, and gathering additional information, see the monthly What’s New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation, at http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html\n\nSubscribe to the What’s New in Cisco Product Documentation as a Really Simple Syndication (RSS) feed and set content to be delivered directly to your desktop using a reader application. The RSS feeds are a free service and Cisco currently supports RSS Version 2.0.\n\nDocument Change History\n\nTable 1 provides the revision history for the Cisco BTS 10200 Softswitch CORBA Adapter Interface Specification Programmer’s Guide, Release 7.0.\n\n<table>\n<thead>\n<tr>\n<th>Table 1 Revision History</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Version Number</strong></td>\n</tr>\n<tr>\n<td>OL-23043-01</td>\n</tr>\n</tbody>\n</table>\nCHAPTER 1\n\nCORBA Architecture and Application Programming Interface\n\nRevised: July 2010, OL-23043-01\n\nThe Cisco BTS 10200 Softswitch CORBA Adapter Interface Specification Programmer Guide describes the CORBA adapter (CAD). CAD provides a machine-to-machine interface (MMI) over Common Object Request Broker Architecture (CORBA). This architecture is defined by the Object Management Group (OMG) organization.\n\nNote\n\nThe Cisco BTS 10200 Softswitch CORBA software is installed as part of the Cisco BTS 10200 Softswitch software. For installation instructions, see the document Cisco BTS 10200 Softswitch Application Installation Release 7.0.\n\nThe CAD interface provides a provisioning method for the Cisco BTS 10200 Softswitch product that parallels the Command Line Interface (CLI) adapter in capabilities. CAD provides an abstraction of the BTS 10200 in a consistent, object-oriented model. Discussion of the actual object model for this interface is not within the scope of this document.\n\nThe Cisco BTS 10200 Softswitch Command Line Interface Database is the definitive source for token descriptions (parameters) and their values, as used in the CORBA interface.\n\nNote\n\nThis document describes CORBA using OpenORB. If you are using Visibroker, use the Cisco BTS 10200 Softswitch Release 3.2, 3.3, 3.5 Programmers Specification.\n\nThis chapter describes the Common Object Request Broker Architecture (CORBA) adapter architecture and application programming interface (API) for the BTS 10200.\n\nCORBA Adapter Architecture\n\nThe CORBA adapter (CAD) interface leverages the adapter architecture of the Element Management System (EMS) component in the BTS 10200. This architecture allows for a variety of adapters to provide operations, administration, management, and provisioning (OAM&P) by adapting the external interface to a common infrastructure in the EMS. Figure 1-1 illustrates the overall architecture for the CAD and shows the CORBA architecture.\nThe architecture provides dual mode support for secure and nonsecure CORBA, which are active at the same time. This was an install option in previous releases. The nonsecure mode and the secure mode are fully supported. As part of this dual mode support, there are two Java processes on the BTS 10200 EMS that manage the CIS application. Each process is marked with a unique name to indicate its unique function.\n\n- Nonsecure is -D_CIS_IIOOP\n- Secure is -D_CIS_SSLIOP\n\nThere are side effects to this dual mode of support. When both modes are active, the new secure CORBA mode does not behave as it did in previous releases. This new behavior includes name space collisions, so a new secure POA context and name space are provided to avoid problems.\n\nBoth the nonsecure mode and the secure mode only allow connections on the active EM01 EMS application and automatically drop connections if the active EM01 application fails or manually switches over to its redundant mate. In addition, the application removes its objects from the local INS or NameService so that no new queries can successfully resolve to that particular EMS. This solves a legacy CORBA issue by preventing any provisioning from a standby EMS.\n\nThe CORBA installation automatically uses VIP (Virtual IP Address) as the iiop.hostname, if the VIP is configured. If VIP is not configured, the first EMS Management IP address is used as the iiop.hostname. This allows the NameService to listen to all IP addresses on the active EMS. For the use of VIP, please refer to the Cisco BTS 10200 Softswitch Command Line Interface Database.\n\nInstalling CORBA also installs the CORBA Software Developers Kit (SDK) onto the EMS. The installer can run the sample test program to verify the CORBA installation. See “Sample CORBA Client Package (BTSxsdk) Implementation” for more information.\n\nThe bts.properties file in the CIS application affects client application development. Login sessions expire in 10 minutes with no activity. This means that a command must traverse each session once every 10 minutes to keep a session alive. This is important for any client application that deploys connection pools.\n\n**Figure 1-1 CORBA Architecture**\n\nThe CORBA Adapter (CAD) uses the OpenORB 1.4.0 interface to develop and deploy distributed object-based applications, as defined in the CORBA specification 2.4.2.\nChapter 1 CORBA Architecture and Application Programming Interface\n\nXML Interface\n\nThe XML interface is abstracted from CORBA itself. The OpenORB package uses the Internet Inter-ORB Protocol (IIOP) using either the Transmission Control Protocol (TCP) or the User Datagram Protocol (UDP) for connections. Narrowing on the NameService also produces the BTS10200 objects. Narrowing is covered in great detail in the coding examples in the BTS 10200 Software Developers Kit (SDK) package. The SDK package is bundled with the Cisco BTS 10200 Softswitch application.\n\nTo create separate application-level connections or objects, you must pool some objects and login several times to obtain valid login keys for every instance of the BTS10200 object. Examples are available in the bundled SDK package.\n\nBatch Data Retrieval (Paging)\n\nBatch data retrieval (paging) is available through use of the CLI show command. The use of paging is required for viewing large data sets, but the initial request to set up paging impacts performance. Subsequent requests against the same paged data are faster because the data is cached for quick retrieval. This applies to a specific session (key) and any other command executed against that session flushes any cached data. All requested paged data must be contiguous for optimal performance. For more information, see the Cisco BTS 10200 Softswitch Operations, Maintenance, and Troubleshooting Manual and the Cisco BTS 10200 Softswitch Command Line Interface Database.\n\nNote\n\nFor the limit token, in any single show, CORBA automatically limits paging to 500 rows.\n\nSessions and Transactions\n\nCORBA supports up to 50 simultaneous sessions. A session is created by any valid login to the CORBA interface. CORBA also supports 20 concurrent transactions. A transaction is any specific request; for example, show or change.\n\nEach login session allocates its own specific set of resources much like an individual CLI. These sessions are audited for idle activity. If the session is not active (no command executed) in a 10 minute period, the session is declared idle and removed from the interface, and all resources are closed.\n\nORB Specifications\n\nThe Object Request Broker (ORB) used in the CAD interface is the OpenORB 1.4.0 compliant package. The ORB also supports other advanced features like the portable object adapter (POA). POA is the implementation model used in CAD.\n## Compiler Tools\n\nThe minimum required compiler is the J2SE Development Kit (JDK)1.4.1. The BTS 10200 uses JDK1.6.0 or JDK6 for compilation and for the Java Runtime Environment (JRE). Additional tools that may be required for the client side application are:\n\n- Xerces parsers\n- ECS Report Builder\n\n## ORB Deployment\n\nFigure 1-2 shows the ORB deployment process.\n\nWhen you use OpenORB for the client side application, you must perform a few basic steps to ensure that the client environment is properly set up and ready for the application. The first is to configure the JVM on the client machine to use OpenORB as the primary ORB for Java. This can be done at runtime or it can be permanently set in the orb.properties of the JVM. To perform the latter requires privileges of the owner of the JVM install. In most cases this is root. The root user must execute the following command:\n\n```\njava -jar openorb_orb-1.4.0.jar\n```\n\nThis places the orb.properties settings in the correct location with the following values:\n\n```\norg.omg.CORBA.ORBClass=org.openorb.orb.core.ORB\norg.omg.CORBA.ORBSingletonClass=org.openorb.orb.core.ORBSingleton\n```\n\nOtherwise, the settings must be supplied as environmental overrides to each invocation of the client application.\n\nAdditional values that are of use to the client programmer are the OpenORB DEBUG options. These control the volume of debug information produced by the client application. The debug information is sent to the standard output of the application. The programmer who wishes to capture this data in log files, must use the basic shell redirect commands to redirect the data. Other environments such as web\nservices can behave differently. The options for getting the highest degree of debug output are listed below. These produce IIOP/SSLIIOP message dumps which are the most useful in debugging issues with communications with the BTS 10200.\n\n-Dopenorb.debug.trace=DEBUG -Dopenorb.debug.level=HIGH\n\nThese options are supplied as an environment setting to the client application as part of the Java invocation. The following examples illustrate the interface definition language (IDL) compilation and Java code required for locating the POA and binding it to the compiled IDL objects.\n\nThis OpenORB generic process is a critical part of the development of any client application interfacing to the BTS 10200. The IDL supplied by the BTS 10200 must be compiled into interface classes and then used in the client application.\n\nIDL is a generic term for a language that lets a program or object written in one language communicate with another program written in an unknown language. In distributed object technology, new objects must discover how to run in any platform environment to which they are sent. An ORB is a middleware program that brokersonly client/server relationships between objects.\n\nThis code example uses the Java package tree as developed in the BTS 10200 product. This code can vary. Other clients can specify a different package tree to contain the IDL interface objects. See the SDK for a detailed breakdown of this script.\n\n```bash\n#!/bin/sh\n#*****************************************************************************\n# Copyright (c) 2002, 2006 by Cisco Systems, Inc.\n# # AUTHOR: A. J. Blanchard\n# # DESC: Invoke the IDL compiler for the OpenORB package.\n# #*****************************************************************************\n\nset -e\nset -a\n#set -x\n\n# List required jar files\n#\nCLASSPATH=./opt/BTSoorb/lib/logkit.jar:/opt/BTSoorb/lib/openorb-1.0.1.jar:/opt/BTSoorb/lib/openorb_tools-1.3.1.jar:/opt/BTSoorb/lib/xerces.jar:/opt/BTSoorb/lib/avalon-framework.jar:/opt/BTSoorb/lib/openorb_ots-1.3.1.jar:/opt/BTSoorb/lib/openorb_pss-1.3.1.jar:/opt/BTSoorb/lib/openorb_ins-1.3.1.jar:/opt/BTSoorb/lib/openorb_tns-1.3.1.jar\nexport CLASSPATH\n\njava -classpath $CLASSPATH org.openorb.compiler.IdlCompiler $1 -jdk1.4 -all -verbose -d ./\n```\n\nJava files are generated in a local directory tree specified in the package directory. This package path is required in the bind logic to find the object interface implementation.\n\n```bash\n#!/bin/sh\n#*****************************************************************************\n# Copyright (c) 2002, 2006 by Cisco Systems, Inc.\n# # AUTHOR: A. J. Blanchard\n# # DESC: Compile Java ORB programs with the required components from OpenORB.\n# #*****************************************************************************\n\n```\nChapter 1 CORBA Architecture and Application Programming Interface\n\n### ORB Specifications\n\n```bash\nset -e\nset -a\n#set -x\nCLASSPATH=./opt/BTSoorb/lib/logkit.jar:/opt/BTSoorb/lib/openorb-1.3.1.jar:/opt/BTSoorb/lib/openorb_tools-1.3.1.jar:/opt/BTSoorb/lib/xerces.jar:$HOME/mb/devel/em/lib/cad.jar:$HOME/mb/devel/em/lib/ecs-1.4.1.jar:/opt/BTSoorb/lib/openorb_os-1.3.1.jar:/opt/BTSoorb/lib/openorb_pss-1.3.1.jar:/opt/BTSoorb/lib/openorb_ins-1.3.1.jar:/opt/BTSoorb/lib/openorb_tns-1.3.1.jar\nexport CLASSPATH\njavac -classpath $CLASSPATH -d ./ $*\n```\n\nYou compile a package of Java files to generate the required class files. These class files must exist in the client classpath.\n\n**Note**\n\nThis is a common example where all the Java files in a single directory are built with a single command. This is one of the fastest ways to compile bulk Java code.\n\nThe BTS 10200 offers an SDK with a complete range of examples that utilize the CORBA interface. These include many topics such as\n\n- CLI\n- Batch file processing\n- Multi-thread concurrency\n- SSL\n\n**Note**\n\nThe example below illustrates the basic abstraction of the BTS 10200 objects. If other tools are used, you must modify the IDL objects as well as the OpenORB files.\n\n```java\npackage com.sswitch.oam.ccc;\n\nimport java.lang.*;\nimport java.io.*;\nimport java.util.*;\nimport java.text.*;\n// CORBA stuff\nimport org.omg.CORBA.*;\nimport org.omg.PortableServer.*;\nimport org.omg.Messaging.*;\n// XML Stuff\nimport org.apache.ecs.xml.*;\nimport org.apache.ecs.*;\nimport org.w3c.dom.*;\nimport org.xml.sax.*;\nimport org.apache.xml.serialize.*;\n// BTS Code jar files...\nimport com.sswitch.oam.cad.*;\nimport com.sswitch.oam.xml.*;\nimport com.sswitch.oam.util.*;\n\n/**\n * CorbaXmlIntf.java\n * Copyright (c) 2002, 2006 by Cisco Systems, Inc.\n * -- This is the client side driver stub. This allows the client application\n * to generate the Request object which is then digested in this class as a\n * XML document and sent as a request to the CORBA server. The results are\n * then returned to the user or the CORBA exception is thrown.\n */\n```\npublic class CorbaXmlIntf {\n\n /*\n * Class private data\n */\n private String[] objArgs;\n private org.omg.CORBA.ORB objOrb;\n private org.omg.CosNaming.NamingContextExt objContext;\n private com.sswitch.oam.cad.Bts10200 objBts;\n private com.sswitch.oam.cad.Bts10200_Security objBtsSec;\n private org.omg.CORBA.StringHolder objKey;\n\n /**\n * This is the primary execution method for the object. It performs the\n * actual request and calls for the print of the reply.\n */\n public void connect() throws CadExceptions {\n try {\n bind();\n objKey = new org.omg.CORBA.stringholder();\n objBtsSec.login(\"btsadmin\", \"btsadmin\", objKey);\n Log.info(\"BTS10200 Login successful: \"+objKey.value);\n }\n catch (Exception e) {\n Log.error(\"Exception in CORBA Bind/Login = \"+\n Util.stackTraceToString(e));\n throw new CadExceptions(1, e.toString());\n }\n }\n\n /**\n * This method generate the request to the CORBA server and returns\n * the reply or an exception if the interface throws an exception.\n * The argument \"request\" must be an XML formatted document.\n */\n @param request This XML request document.\n @returns String This is the XML formatted answer.\n public String request(String request)\n throws CadExceptions {\n String answer=null;\n try {\n org.omg.CORBA.StringHolder reply = new org.omg.CORBA.StringHolder();\n // Issue request to BTS 10200\n objBts.request(request, objKey.value, reply);\n answer = reply.value;\n }\n }\n\n}\n// Build an XMLReply from the document\nanswer = reply.value;\n}\ncatch (Exception e) {\n Log.warning(\"Request Command Exception:\\n \" +\n Util.stackTraceToString(e));\n throw new CadExceptions(1, e.toString());\n}\nreturn answer;\n} // end request()\n\n/**\n * This method generate the request for a command document to the\n * CORBA server and returns the reply or an exception if the interface\n * throws an exception.\n * *\n * @param noun This noun for the request.\n * @param verb This verb for the request.\n * @returns String This is the XML formatted answer.\n */\npublic String getCommandDoc(String verb, String noun)\n throws CadExceptions\n{\n String answer = null;\n try {\n org.omg.CORBA.StringHolder reply = new org.omg.CORBA.StringHolder();\n // Issue request to BTS 10200\n objBts.getCommandDoc(noun, verb, objKey.value, reply);\n // Build an XMLReply from the document\n answer = reply.value;\n }\n catch (Exception e) {\n Log.warning(\"Request Command Exception:\\n \" +\n Util.stackTraceToString(e));\n throw new CadExceptions(1, e.toString());\n }\n return answer;\n} // end getCommandDoc()\n\n/**\n * This method generate the request for a command document to the\n * CORBA server and returns the reply or an exception if the interface\n * throws an exception.\n * *\n * @param noun This noun for the request.\n * @param verb This verb for the request.\n * @returns String This is the XML formatted answer.\n */\npublic String getExtCommandDoc(String verb, String noun)\n throws CadExceptions\n{\n String answer = null;\n try {\n org.omg.CORBA.StringHolder reply = new org.omg.CORBA.StringHolder();\n // Issue request to BTS 10200\n objBts.getExtCommandDoc(noun, verb, objKey.value, reply);\n // Build an XMLReply from the document\n answer = reply.value;\n }\n catch (Exception e) {\n Log.warning(\"Request Command Exception:\\n \" +\n Util.stackTraceToString(e));\n throw new CadExceptions(1, e.toString());\n }\n return answer;\n} // end getExtCommandDoc()\npublic void disconnect() throws CadExceptions {\n objBtsSec.logout(objKey.value);\n return;\n}\n\n/*=====================================================================*/\n/**\n* This method binds to the target CORBA objects for us to operate\n*/\nprotected void bind() throws org.omg.CORBA.ORBPackage.InvalidName,\n org.omg.CosNaming.NamingContextPackage.InvalidName,\n\n org.omg.CosNaming.NameComponent[] nameComponent = null;\n org.omg.CORBA.Object result = null;\n insLocate();\n result = objContext.resolve(objContext.to_name(\"Bts10200_Security_poa\"));\n objBtsSec = Bts10200_SecurityHelper.narrow(result);\n result = objContext.resolve(objContext.to_name(\"Bts10200_poa\"));\n objBts = Bts10200Helper.narrow(result);\n Log.info(\"Basic POA(s) have been located and bound.\");\n return;\n}\n\n/*=====================================================================*/\n/**\n* Load the name service and find the context for the CORBA objects.\n* Remember, the INS must be the one located on the BTS. This has the\n* object references. Use a 'corbaloc:' for now but later a migration\n* to URL for name service location would be good.\n*/\nprotected void insLocate() throws org.omg.CORBA.ORBPackage.InvalidName {\n\n //System.out.println(\"Locate NameService in system.\");\n org.omg.CORBA.Object initial_context_obj =\n objOrb.resolve_initial_references(\"NameService\");\n objContext = org.omg.CosNaming.NamingContextExtHelper.narrow(initial_context_obj);\n Log.info(\"NameService found in initial context.\");\n return;\n}\n\n} // end CorbaXmlIntf\n\n• Actual implementations can make the POA selection dynamic and based on some form of navigation\nto a site (for example, to a softswitch home location or perhaps part of the softswitch ID). Once a\nPOA is selected, all object implementations are the same. No site-specific behaviors are exhibited\nin any object. However, site-specific attributes are present, and are derived based on the local\ndatabase contents.\nNameService\n\nThe OpenORB NameService module provides an Object Management Group (OMG) compliant implementation of the NameService Specification Version 1.2 (September 2002). This module is required for CORBA operations on the BTS 10200. Clients attach to the NameService to obtain the references to the BTS 10200 CORBA objects through the corbaloc process. When using OpenORB on the client side of the application, apply the following syntax to connect to the NameService:\n\n```\ncorbaloc::1.2@<Host Name>:14001/NameService\n```\n\nThe `corbaloc` string can be supplied in the OpenORB.xml configuration file located in the /opt/BTSororb/config directory as an initial reference or it can be dynamically built in the client application as required. Cisco recommends that the hostname be an IP address.\n\nEach BTS 10200 EMS comes with management interfaces, and the INS or NameService must utilize a hostname that resolves across both of these management interfaces. But client-side access is not influenced by the interface that is used. The client must be aware that a given management interface can be down for various reasons and that this can impact access to the name service. You may need to use both the IP address or retries on the hostname to deal with switch or router troubles that may naturally occur over time on any given subnet.\n\nEach BTS 10200 comes with its own pair of duplex INSs. Each INS represents the objects from a single side of the BTS 10200. Use this resource location string to derive a reference to the NameService. Each Cisco BTS 10200 Softswitch comes with its own instance of a name service, and a name service can be utilized separately for each EMS. The Cisco BTS 10200 Softswitch default UDP port for this module is 14001. In the OpenORB model, this value is passed in the configuration file OpenORB.xml. The SDK contains examples of this configuration, as well as example code for building working examples using the OpenORB client implementation.\n\nMultiple NameService modules can be used by applying a request interceptor. A proxy object allows a request to be forwarded by means of the ForwardRequest (CORBA 3.0 spec. 1.3.1) protocol. See “Proxy” for more information.\n\nThe following example shows an object resolution using the NameService module. At this time the basic POA is used as a root-level reference to the local Cisco BTS 10200 Softswitch.\n\n```java\norg.omg.CORBA.Object initial_context_obj =\n objOrb.resolve_initial_references(\"NameService\");\nobjContext =\n org.omg.CosNaming.NamingContextExtHelper.narrow(initial_context_obj);\nresult = objContext.resolve(objContext.to_name(\"Bts10200_poa\"));\nobjBts = Bts10200Helper.narrow(result);\n```\n\nBTS 10200 Softswitch IDL\n\nThe IDL is used to express the object-level interface in the CAD interface. This object interface includes the attributes and behaviors of the objects. This section provides an overview of the IDL for the BTS 10200. The IDL objects define access to the XML descriptions and documents used to provision the BTS 10200. A full description of the XML document is given in a later chapter. Mostly, CORBA acts as the transport for these XML documents.\n\nThe bts10200.idl file contains the general system-wide data structures and type definitions. It also contains the error interfaces (exceptions). See the “Cisco BTS 10200 Softswitch IDL Code” section on page 2-6 for the full text of the bts10200.idl file. This file contains all objects that are defined for use in the BTS 10200. The breakdown of each object is listed below.\n• **Bts10200_Security**—The primary security object. It is used to create login keys for use in another object. This object must be present to enable access to the BTS 10200.\n\n• **Bts10200**—The basic object used to retrieve XML description documents as well as provisioning and control documents.\n\n• **CadException**—The object used to report all errors in the Cisco BTS 10200 Softswitch CAD interface.\n\n• **Macro**—This object defines and executes custom `show` or `display` commands on the BTS 10200. This allows a user to create simplified `display` commands from complex relationships and permanently store them for recall later as “macro” commands.\n\n### BTS 10200 API\n\nThis section covers the actual API calls to the CAD interface. The assumption is that the client application is developed in the Java language. This does not prohibit the use of C++. However, that is not within the scope of this document.\n\nAll parameters that are listed are required for each invocation of methods in the associated object.\n\n### BTS 10200 Security API\n\nThe BTS 10200 security object (Bts10200_Security) provides a user several levels of security for the CAD interface in the BTS 10200. It allows authorized users to obtain a security key and use this key for all future transactions. This object must be used prior to all other CORBA method invocations in the interface. This key is valid in the CAD interface for the life of the user’s session. The key is no longer valid once the logout method has been invoked. Likewise, the security key expires after 10 minutes if the system has not been accessed during that period of time, and the user is automatically logged out of the CAD interface. The user name and password are the same values allowed in the CLI/MAC adapter interfaces, and the same authorization permissions apply.\n\nEach method in this section is part of the Bts10200_Security interface. The parameters listed are required for each method and must contain data.\n\n#### Login\n\nThe login method provides authentication of a CORBA interface user. It utilizes the same user security as the FTP or CLI adapter. This method returns a string value defined as a key. This key is required for all transactions against the CAD interface. It is an authentication key indicating the specific authorization of a particular user. The method is defined by the following code:\n\n```java\nint login (java.lang.String user, java.lang.String passwd, java.lang.StringHolder key)\nthrows CadExceptions\n```\n\n- **Return value**—Status indicating success or failure of the operation. Failure means the facility is unavailable. Success means the operation was completed.\n\n- **Exception**—A CadException means there is an operational error in processing the request. This includes faults with the parameter types, ranges, and database access.\nThe BTS 10200 implementation of CORBA does not support RADIUS authentication. Therefore, if a user presumes that an attempt to login is supported by a pluggable authentication module (PAM) and RADIUS authentication, the operation fails and the user is required to accomplish a UNIX login. In such cases, attempts to login fail.\n\n**Logout**\n\nLogging out terminates a login session. This destroys the validity of the authentication key. Once you log out, the key can no longer be used for other invocations. The log out method is defined in the following code:\n\n```java\nint logout (java.lang.String) throws CadExceptions\n```\n\n- **Return value**—Status indicating success or failure of the operation. A failure indication means the facility is unavailable. A successful return indicates the operation was completed.\n- **Exception**—A CadException means there is an operational error in processing the request. This includes faults within the parameter types, ranges, and in database access.\n\n**BTS 10200 Provisioning API**\n\nThe BTS 10200 object (Bts10200) provides provisioning interface functions to the BTS 10200 CLI engine for authorized users. Both input and output are in XML as described in Chapter 2, “Extensible Markup Language Processing.” The CLI commands are parsed into an XML document before the commands are sent through the CORBA interface. The CORBA CIS server then executes the CLI provisioning commands and sends back the reply in an XML document. Each method in this section is part of the Bts10200 interface. The parameters listed are required for each method and must contain data.\ngetCommandDoc\n\ngetCommandDoc retrieves command descriptions. getCommandDoc obtains the XML document describing the command syntax and options for a specific noun/verb combination. The following code defines how getCommandDoc is used:\n\n```java\nvoid getCommandDoc (java.lang.String noun, java.lang.String verb, java.lang.String key,\n org.omg.CORBA.StringHolder reply) throws CadExceptions\n```\n\nwhere:\n- **parameter noun** is the command noun\n- **parameter verb** is the command verb\n- **parameter key** is the authorization key obtained in login\n- **parameter reply** is the XML reply of the command syntax and options\n- **exception** (cadexception) means there is an operational error in processing the request. This includes faults with the parameter types, ranges, and database access.\n\nrequest\n\nrequest processes an XML document-based provisioning request through the CORBA interface. The CORBA CIS server executes the provisioning commands and sends back the reply in an XML document. The following code defines how request is used:\n\n```java\nvoid request (java.lang.String command, java.lang.String key, org.omg.CORBA.StringHolder\n reply) throws CadExceptions\n```\n\nwhere:\n- **parameter command** is the provisioning command request in the XML document\n- **parameter key** is the authorization key obtained in login\n- **parameter reply** is the XML reply of the command execution in the CLI engine\n- **exception** (cadexception) means there is an operational error in processing the request. This includes faults with the parameter types, ranges, and database access.\n\nCORBA Session Manageability Feature\n\nThe CORBA Session Manageability (CSM) feature (introduced in Release 5.0 Maintenance Release 1 (MR1) of the Cisco BTS 10200 Softswitch) enhances the manageability of user sessions. The feature affects three areas:\n\n1. CORBA SDK\n2. CORBA Interface Servant for both secure and nonsecure (CIS-IIOP/CIS-SSLIOP)\n3. Session and System Manager (SMG for EMS)\n\nThe SDK changes are related primarily to the use of the API. These changes are most noticeable on the client side of a deployment. Session information is processed as part of the existing Session Manager capabilities.\nSoftware Developer’s Kit\n\nThere are two new login APIs in the SDK client code. The first API is `loginWithStatus` that returns password aging status. The other API is `loginResetPassword` that resets a new password when an old password is aged. The *SDK Programmer's Guide* contains the details of session management features and the commands you can use to display and clear client sessions in CORBA. It also explains policy behavior and how this behavior impacts login attempts.\n\nCORBA Interface Servant\n\nThis feature impacts the CORBA Interface Servant (CIS) application, regardless of secure or non-secure access, in the common user security area of password validation and of tracking user attributes such as idle login and security keys.\n\nThe user security information is externalized by use of an API. This API provides queries that enable you to take snapshots of the present condition of sessions. You obtain this information from database statistics tables in the MySQL database.\n\nAdditional message handler functions enable you to obtain reports that contain session information. Certain of these added functions provide commands that can terminate sessions. This interface utilizes the user security API.\n\nThe Session Control Policy, which is processed in a minute-based looping operation, screens and removes sessions that match a record in the policy. A new CLI command supplies policy management.\n\nThe bts.properties file contains the Maximum User Limit (item name: max.users) and Idle Timeout (item name: idle.timeout), which can be modified manually. The CIS relies on these numbers to decide if: (1) the maximum user limit is reached, or (2) the user session must be timed out because it is idle. The CIS dynamically reads the file upon user login and during session audit. If the maximum number of users is set to a value higher than 50, the hard limit of 50 maximum users applies.\n\nSession and System Manager\n\nThe CORBA Session Manageability feature adds the following new capabilities:\n\nUser Session Display—Display current secure and nonsecure CORBA sessions using the new `show client-session` and `report client-session` commands. The returned data also includes any current CLI sessions.\n\nManual Session Removal—Remove a CORBA session or a CLI session using the `stop client-session` command. The present `stop session` command applies to CLI users only. Additional information clearly indicates individual sessions.\n\nPolicy-driven Smart Session Management—Includes the smart removal of idle sessions allowing new sessions to log in, while allowing administrative access at all times. This does not affect idle time. The maximum duration of a session is set whether a session is idle or not. Default idle time is 10 minutes.\n\nPassword Aging Notification—Aging notification of the password for a given user when `loginWithStatus` API is used.\n\nCORBA Password Reset—Users can log in and reset aging password using the `loginResetPassword` API. If a password expires, access is denied until the password is reset.\n\nDisable Password Aging—Set passwords to never expire when adding a new user or using the `change user` command. Set the status token to PERSIST.\nAlarms and Events for Critical Session Handling—Issue warning and major alarms and events when the session threshold of usage is reached. Issue an alarm when the maximum number of login sessions is reached. Issue an event when a user session is terminated because of a policy violation. This behavior is managed through the Policy table.\n\nUser Security Manager\n\nThe User Security Manager (USM) has a new status. This status disables the password aging function. The status has the following attributes:\n\n- DISABLED—The user is locked out and the user cannot access the system.\n- ENABLED—The user is active and current for all attributes including password aging.\n- PERSIST—The user has no password aging.\n\nCommand Line Interface Reference\n\nThe introduction of the CORBA Session Manageability feature required the addition of two new BTS CLI tables: the EMS Session Control Policy table and the EMS Client Session table. To support the feature, the User table is modified. For complete definitions of these new and changed tables see the Cisco BTS 10200 Softswitch CLI Database.\n\nEMS Session Control Policy Table\n\nThe EMS Session Control Policy (ems-session-control-policy) table specifies a policy for stopping any sessions that match any of the records in the table. This policy allows administrators to define a session duration limit for a user or set a hard duration limit for all CORBA sessions. The policy is validated per minute in the CORBA server. If a session is removed because of a policy violation, an event is issued to track the incident.\n\nFor a complete definition of the ems-session-control-policy table, see the Cisco BTS 10200 Softswitch CLI Database.\n\nUser Table\n\nThe new token, STATUS, is added to the User table. The STATUS token allows you to enable or disable a user account or set the password to never expire.\n\nFor a complete definition of the User table, see the Cisco BTS 10200 Softswitch CLI Database.\n\nClient Session Table\n\nThe Client Session (client-session) table tracks user session information. The show command retrieves data from this table for both CLI and CORBA user sessions. Compared to the session command, the client-session command shows all CLI and CORBA user login sessions. The command does not display application sessions. CLI sessions have terminal IDs; CORBA sessions have session keys. The client-session command allows an administrator to force users off the system for upgrade or resource management purposes. An administrator can stop idle sessions and allocate resources to other user sessions, which may be necessary due to the limitation on the number of logins allowed.\n\nFor a complete definition of the client-session table, see the Cisco BTS 10200 Softswitch CLI Database.\nMacro Command\n\nThe BTS 10200 must be able to provide a high-level view of complex data in its database. Normally, determining relationships between database items requires several commands and multiple requests to the database. This slow and costly process impedes the progress of Operations Support System (OSS) management systems. Therefore, an optimized approach is required where several operations can be collapsed into a single request to the database, which returns the correct related data based on the set of defined rules.\n\nThe code that enables you to view complex data relationships in the BTS 10200 is referred to as a macro. A macro is a single command that builds complex queries across multiple commands by using relationship rules defined by the user.\n\nThe macro command is specific to the BTS 10200 and works with both simplex and duplex configurations. The primary focus of this command in this document is its utilization in the CORBA interface definition language (IDL) interface of the CORBA Adapter (CAD) feature.\n\nBehaviors and Attributes\n\nThe macro command interface allows users to select and define multiple tables derived from the Cisco BTS 10200 Softswitch database. Normal commands only operate on single devices and/or tables.\n\nThe macro command interface does not allow users to write to the tables in the database. There are many rules and constraints that apply to the database tables that prevent this activity.\n\nMacro Command Management\n\nMacro command management is composed partly of the user commands that create, change, and delete macro command definitions. These user commands allow the definition and manipulation of the actual macro commands and execute as standard provisioning commands. The other primary component is the macro execution. This is provided through the CORBA interface and uses the macro command management rules with additional user-specified data to return the instance values of the macro parameters.\n\nMacro Definition\n\nThe values that are used to build a macro command are validated internally. Technically, each macro is a superset show command of multiple nouns and their associated parameters. All values used in the creation of the macro command are derived from the parameters of nouns and not from the actual table and column names. This helps to preserve the abstraction over the Cisco BTS 10200 Softswitch schema. The following examples of macro command management show typical creation, alteration, and deletion of a Macro command. The sections following the examples define the actual values used in the macro definition and the constraints imposed on them.\n\n```\nadd macro id=CTXG_NUMBERS; \\\n parameters=office_code.NDC, \\n office_code.EC,\\n dn2subscriber.DN,\\n subscriber.CTXG_ID; \\nrules=\"office_code.OFFICE_CODE_INDEX=\\n dn2subscriber.OFFICE_CODE_INDEX,\\n dn2subscriber.OFFICE_CODE_INDEX,\\n dn2subscriber.SUB_ID=subscriber.ID\";\n```\nWhen editing an existing macro, you must enter the parameter to be modified. In this case, the `parameters` and `rules` (and, or) are a list. The entire list must be reentered. The list that was stored in the macro database entry is then replaced. The following example demonstrates this.\n\n```plaintext\nchange macro id=CTXG_NUMBERS; \\\n parameters= office_code.NDC, \\ \n office_code.EC, \\ \n dn2subscriber.DN, \\ \n subscriber.ID;\n```\n\nWhen a macro is no longer required, it can be removed. This is achieved through the `delete macro` command. The only required parameter is the macro ID. All associated definitions for the macro are then removed from the database. The syntax of the `delete macro` command is:\n\n```plaintext\ndelete macro id=CTXG_NUMBERS;\n```\n\nTo display a macro, you need only the macro ID. All static components of the command are returned. The following example shows the syntax of this command:\n\n```plaintext\nshow macro id=CTXG_NUMBERS;\n```\n\n### Macro ID\n\nThe macro ID is used as the handle for all references to a macro definition. If the macro is to be invoked, the ID becomes the noun by which the macro can be invoked. The ID is also the primary key or parameter used in the `change macro`, `delete macro`, and `show macro` commands for editing a particular definition. The ID you use for the macro is presented in a field that contains characters that must be unique to the IDs in all other macros. The ID can be up to 79 characters long. The macro ID provides a unique macro definition that can also be verbose enough to describe the desired operation.\n\n### Parameter List\n\nThe parameter list is used to list the nouns and parameters that are displayed in the Macro command. They constitute the selected items to place in the reply. The value of the parameter list field is a comma-separated list of nouns and parameters from related BTS 10200 commands. This list has the following syntax as input:\n\n```plaintext\nparameters=<noun.parameter>,<noun.parameter>,…,<noun.parameter>;\n```\n\nEach item in the list takes the form of the noun with a period followed by the parameter from that noun. These nouns and parameters are validated through the Element Management System (EMS). Each item in the list must always be addressed in full with the noun and parameter. This is due to the reuse of common parameter names such as ID.\n\nNo implied order of importance is given to the parameters. They are supplied to the command processing in the order they are defined in the macro. No additional data items from other parameters of a given noun are included.\n\n### Rules\n\nThe most critical parts of the Macro command are the rules. These rules manage the relationship of the data to be selected from the BTS 10200 database. These rules amount to the “where” clause of a database selection statement. They help focus the data subset required for operations. There are two basic sets of rules that can be applied to a macro: the `and` rules and the `or` rules as well as `equivalence` and `not`. The generic parameter rules are applied as `and` rules. The definitions of these rules are:\nMacro Command\n\n- **And rules**—One or more sets of data qualifiers indicating a required conditional for the selection of data in the macro. A single **and** rule specifies that a particular noun and parameter must equal some other specific noun and parameter.\n\n- **Or rules**—One or more sets of data qualifiers indicating an optional conditional for the selection of data in the macro. A single **or** rule specifies that a particular noun and parameter can equal some other specific noun and parameter.\n\n- **Equivalence and Not**—The rules section of the **macro** command can contain two variations. They can describe a noun/parameter pair as equivalent or not equivalent. The common syntax for this expression is “=” for equal, or “!=” for not equal.\n\nUser Input\n\nThe user input component is not required for the rules list. User input is supplied at the time the macro is invoked. This additional input is treated as an **and** rule input. The input data defines the subset of data that a rule selects. The rule can use the equivalence syntax to express variations in the data selection. For example, a user may want to find all subscribers that do not have a specific feature.\n\nCORBA/XML Interface\n\nThe CORBA interface servant (CIS) must support a new IDL interface for the **macro** command interface. This involves the use of the following new components. The CIS subsystem supports the definition and execution of the Macro commands.\n\n- **Macro command definition**—Macros that can be defined through the “Bts10200.request(…);” interface as normal provisioning requests are managed.\n\n- **IDL interface definition**—A new IDL method is added to enable the CIS to access a **macro** command that is separate from the standard feature-provisioning interface. This is for the execution of the macro only.\n\n- **CIS implementation of the IDL interface**—An implementation that follows the standard behavior of other CIS interface objects by accepting strings for the authorization key and input arguments. It also returns a string to indicate the response to the macro execution. The following list presents the arguments and information about syntax:\n - **Request**—The XML Request document that contains the additional user-supplied rules for the request as well as the paging facility parameters. The XML Request document must also have the noun key set to the desired macro name so that the IDL interface can execute the request. At this time, the verb key is not used. As a default, **show** is the best option. This avoids future conflicts if writes are allowed.\n - **Key**—A simple string object that contains the actual authentication key provided through the Bts10200_Security interface.\n - **Reply**—The XML Reply document that contains the returned data from the macro execution. This follows the same format as the Reply XML document from the Bts10200 interface.\n\nExternal Interfaces\n\nThis section details the extensions provided in the BTS 10200 software that are reflected in the external interface of the CORBA adapter (CAD) for the BTS 10200. The paging parameters are available for **macro** command execution. These include the limit and start-row parameters.\nCAD Interface\n\nThis section describes the new IDL method signature in the CAD interface.\n\n```java\ninterface Macro {\n void execute(in string request,\n in string key,\n out string reply)\n raises(CadExceptions);\n}\n```\n\nRequest Format\n\nThe following example shows a macro XML Request document, which requests execution of the CTXG_NUMBERS example that was defined in the “Macro Definition” section on page 1-16. Paging parameters are added to the example. These limit the volume of data that is returned during any single reply. Large XML documents fail in the interface. The current default limit is 500 records per request.\n\n```\n<Request Noun=\"CTXG_NUMBERS\" Verb=\"show\">\n <Entry Key=\"subscriber.ctxg_id\" Value=\"rcdn_grp\"/>\n <Entry Key=\"limit\" Value=\"1\"/>\n</Request>\n```\n\nReply Format\n\nThe following is an example of an XML Reply document. This reply is based on the example in the “Request Format” section.\n\n```\n<Reply id=\"Reply\">\n <Status>true</Status>\n <Reason>Success: Entry 1 of 5002 returned.</Reason>\n <Size>1</Size>\n <AbsolutePath>5002</AbsolutePath>\n <StartRow>1</StartRow>\n <DataTable>\n <Row id=\"0\">\n <Column id=\"NDC\">601</Column>\n <Column id=\"EC\">227</Column>\n <Column id=\"DN\">1013</Column>\n <Column id=\"CTXG_ID\">rcdn_grp</Column>\n </Row>\n </DataTable>\n</Reply>\n```\nChapter 1 CORBA Architecture and Application Programming Interface\n\nOperations User Interface\n\nThis section describes changes to the operations user interface as a result of the BTS 10200 Macro command. The standard paging parameters are available for the Macro command execution. These apply to large data sets.\n\nYou can use the operator interface for additional commands to manage the Macro command in the Cisco BTS 10200 Softswitch. These commands are available from the CLI interface. These same commands are available from the CORBA and bulk-provisioning interface.\n\nTable 1-1 shows the user commands that can be generated. [R] in the table indicates required. These are user-defined commands that have a variety of noun (id) and parameter combinations.\n\n<table>\n<thead>\n<tr>\n<th>Noun</th>\n<th>Verb</th>\n<th>Options</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>macro</td>\n<td>add</td>\n<td>id [R]</td>\n<td>Identifier for the macro. The identifier can be from 1 to 79 characters. The identifier must be unique to the IDs in all other macros.</td>\n</tr>\n<tr>\n<td>macro</td>\n<td>add</td>\n<td>parameters [R]</td>\n<td>Comma-separated list of the actual data to return as a result of the macro execution.</td>\n</tr>\n<tr>\n<td>macro</td>\n<td>add</td>\n<td>rules [R]</td>\n<td>Criteria for the display of data in the macro.</td>\n</tr>\n<tr>\n<td>macro</td>\n<td>change</td>\n<td>id [R]</td>\n<td>Identifier for the macro.</td>\n</tr>\n<tr>\n<td>macro</td>\n<td>change</td>\n<td>parameters</td>\n<td>Comma-separated list of the actual data to return as a result of the macro execution.</td>\n</tr>\n<tr>\n<td>macro</td>\n<td>change</td>\n<td>rules</td>\n<td>Criteria for the display of data in the macro.</td>\n</tr>\n<tr>\n<td>macro</td>\n<td>show</td>\n<td>id [R]</td>\n<td>Defines the macro to be displayed.</td>\n</tr>\n<tr>\n<td>macro</td>\n<td>delete</td>\n<td>id [R]</td>\n<td>Identifier for the macro.</td>\n</tr>\n</tbody>\n</table>\nCadexceptions\n\nThe following basic cadexceptions can be returned. The numbers given in the sample code refer to the text in the explanation. The text is returned if the sample code is used. See the “Cadexceptions” section on page 5-1 for recommended actions if necessary.\n\n**Error Message** No Error\n\n**Explanation** This is a placeholder since zero is not an error.\n\n**Sample Code**\n\n```java\npublic static final int EM_NONE=0;\n```\n\n**Error Message** CIS Error\n\n**Explanation** This error is used for internal processing errors that may relate to ORB interaction or other runtime exceptions.\n\n**Sample Code**\n\n```java\npublic static final int EM_ERROR=1;\n```\n\n**Error Message** CIS No Data\n\n**Explanation** This error indicates that there was no data to return from a show command. This may not be a “real” error; however, it is cleaner to throw an exception than a NULL object.\n\n**Sample Code**\n\n```java\npublic static final int EM_NODATA=2;\n```\n\n**Error Message** User Security Error\n\n**Explanation** A fault was found in the user security. This could result from an invalid login through a password or username. This could also result from an internal error in the security system that failed to validate the user identity.\n\n**Sample Code**\n\n```java\npublic static final int EM_USERSEC=5;\n```\n\n**Error Message** Permission Error\n\n**Explanation** A command was attempted that failed the authorization tests for that command. The user does not have permission to execute this command.\n\n**Sample Code**\n\n```java\npublic static final int EM_PERMISSION=6;\n```\nError Message Error Message: Block Error\n\nExplanation All provisioning on the switch has been blocked. The command may have been perfectly well formed and the connection is still valid. This just indicates the BTS 10200 is in a maintenance mode.\n\nSample Code\npublic static final int EM_BLOCK=7;\n\nError Message Linkage Error\n\nExplanation The linkage failed.\n\nSample Code\npublic static final int EM_LINKAGE=10;\n\nError Message Exception In Initializer Error\n\nExplanation The initialization invoked by this method fails.\n\nSample Code\npublic static final int EM_INIT=11;\n\nError Message Class Not Found Exception\n\nExplanation The class cannot be located.\n\nSample Code\npublic static final int EM_NOTFOUND=12;\n\nError Message Illegal Access Exception\n\nExplanation The class or initializer is not accessible.\n\nSample Code\npublic static final int EM_ACCESS=13;\n\nError Message Instantiation Exception\n\nExplanation The class represents an abstract class, an interface, an array class, a primitive type, or void; or, this message may be generated if the instantiation fails for some other reason.\n\nSample Code\npublic static final int EM_INSTANCE=14;\nError Message Security Exception\n\nExplanation There is no permission to create a new instance.\n\nSample Code\npublic static final int EM_SECURITY=15;\n\nError Message Invalid Request Exception\n\nExplanation The request is not valid or cannot be initialized\n\nSample Code\npublic static final int EM_REQUEST=16;\n\nError Message Invalid Noun Exception\n\nExplanation The command noun is not found or is invalid.\n\nSample Code\npublic static final int EM_NOUN=17;\n\nError Message Invalid Verb Exception\n\nExplanation The command verb is not found or is invalid.\n\nSample Code\npublic static final int EM_VERB=18;\n\nError Message SQL Exception\n\nExplanation The database cannot be accessed, if the constraints are violated, if there is another table conflict, if there is a resource issue, or any other Oracle-related cause.\n\nSample Code\npublic static final int EM_DATABASE=19;\n\nError Message Invalid Value Exception\n\nExplanation A parameter value exceeds the valid range or some other restriction like text length, pick-list, and so forth.\n\nSample Code\npublic static final int EM_VALUE=20;\nError Message Invalid Key Exception\n\nExplanation An invalid key or token was used to describe some data value.\n\nSample Code\npublic static final int EM_KEY=21;\n\nError Message Missing Parameter Exception\n\nExplanation One or more required parameters were not included in the command parameter data.\n\nSample Code\npublic static final int EM_PARAM=22;\n\nError Message Session in Use\n\nExplanation Indicates the user session is valid but busy.\n\nSample Code\npublic static final EM_SESS_INUSE = 23;\n\nError Message Session invalid\n\nExplanation Indicates that the user is no longer logged into the system or the session key is not valid.\n\nSample Code\npublic static final EM_SESS_INVALID = 24;\nThis chapter describes the Extensible Markup Language (XML) process in the Common Object Request Broker Architecture (CORBA) adapter.\n\nXML and Components\n\nAlong with XML, the primary component of the CORBA adapter is the CORBA interface servant (CIS) Java program. In addition, there are dependencies on related components in the managed object (MO) Java package. The required packages are as follows:\n\n- Apache XML\n- Xerces (parser)\n- ECS (XML Document Building Tool Kit)\n\nXML and the CIS Java packages are central, functional components in the Cisco BTS 10200 Softswitch. There is no larger object model applied to the Softswitch. A larger object model is deferred until a Cisco Systems standard model is created. This model covers applications for packet telephony for a variety of applications.\n\nXML in the CORBA Interface Servant\n\nThis section describes how to use XML in the CIS. Terms used in this section follow those used in XML specifications. This is to avoid confusion in the use of terms such as element, subelement, and attribute.\n\nCIS Functions\n\nSchemas are provided for client-side verification of the XML document structure. These schemas cover the following items:\n\n- ManagedObject\n- Request\n- Reply\nThe schema for a ManagedObject follows the format listed below.\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<xs:schema xmlns:xs=\"http://www.w3.org/2001/XMLSchema\" elementFormDefault=\"qualified\">\n <xs:element name=\"ManagedObject\">\n <xs:complexType>\n <xs:sequence>\n <xs:element ref=\"MOAttribute\" maxOccurs=\"unbounded\"/>\n </xs:sequence>\n <xs:attribute name=\"Verb\" type=\"xs:string\" use=\"required\"/>\n <xs:attribute name=\"id\" type=\"xs:string\" use=\"required\"/>\n </xs:complexType>\n </xs:element>\n <xs:element name=\"MOAttribute\">\n <xs:complexType>\n <xs:sequence>\n <xs:element ref=\"Required\"/>\n <xs:element ref=\"Type\"/>\n <xs:element ref=\"Default\"/>\n <xs:element ref=\"HelpText\"/>\n <xs:element ref=\"Label\"/>\n <xs:element ref=\"Parser\" minOccurs=\"0\"/>\n <xs:element ref=\"Permitted\" minOccurs=\"0\"/>\n <xs:element ref=\"Fk\" minOccurs=\"0\"/>\n </xs:sequence>\n <xs:attribute name=\"id\" type=\"xs:string\" use=\"required\"/>\n </xs:complexType>\n </xs:element>\n <xs:element name=\"Required\" type=\"xs:boolean\"/>\n <xs:element name=\"Type\">\n <xs:simpleType>\n <xs:restriction base=\"xs:string\">\n <xs:enumeration value=\"single\"/>\n <xs:enumeration value=\"text\"/>\n <xs:enumeration value=\"multi\"/>\n </xs:restriction>\n </xs:simpleType>\n </xs:element>\n <xs:element name=\"Default\" type=\"xs:string\"/>\n <xs:element name=\"HelpText\" type=\"xs:string\"/>\n <xs:element name=\"Label\" type=\"xs:string\"/>\n <xs:element name=\"Noun\" type=\"xs:string\"/>\n <xs:element name=\"Param\" type=\"xs:string\"/>\n <xs:element name=\"Parser\">\n <xs:complexType>\n <xs:sequence>\n <xs:element ref=\"JavaScript\"/>\n <xs:element ref=\"RegExp\"/>\n </xs:sequence>\n <xs:attribute name=\"id\" use=\"required\" type=\"xs:string\"/>\n </xs:complexType>\n </xs:element>\n <xs:element name=\"JavaScript\" type=\"xs:string\"/>\n</xs:schema>\n```\nThe schema for a Request follows the format listed below.\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<xs:schema xmlns:xs=\"http://www.w3.org/2001/XMLSchema\" elementFormDefault=\"qualified\">\n <xs:element name=\"Request\">\n <xs:complexType>\n <xs:sequence>\n <xs:element ref=\"Entry\" maxOccurs=\"unbounded\"/>\n </xs:sequence>\n <xs:attribute name=\"Verb\" type=\"xs:string\" use=\"required\"/>\n <xs:attribute name=\"Noun\" type=\"xs:string\" use=\"required\"/>\n </xs:complexType>\n </xs:element>\n <xs:element name=\"Entry\">\n <xs:complexType>\n <xs:attribute name=\"Key\" type=\"xs:string\" use=\"required\"/>\n <xs:attribute name=\"Value\" type=\"xs:string\" use=\"required\"/>\n </xs:complexType>\n </xs:element>\n</xs:schema>\n```\n\nThe schema for a Reply follows the format listed below.\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<xs:schema xmlns:xs=\"http://www.w3.org/2001/XMLSchema\" elementFormDefault=\"qualified\">\n <xs:element name=\"Reply\">\n <xs:complexType>\n <xs:sequence>\n <xs:element ref=\"Status\"/>\n <xs:element ref=\"Reason\"/>\n <xs:element ref=\"Size\"/>\n <xs:element ref=\"AbsoluteSize\"/> \n <xs:element ref=\"StartRow\"/> \n <xs:element ref=\"DataTable\"/> \n </xs:sequence>\n <xs:attribute name=\"id\" type=\"xs:string\" use=\"required\"/>\n </xs:complexType>\n </xs:element>\n <xs:element name=\"Status\" type=\"xs:boolean\"/>\n <xs:element name=\"Reason\" type=\"xs:string\"/>\n <xs:element name=\"Size\" type=\"xs:integer\"/>\n</xs:schema>\n```\n<xs:element name=\"AbsoluteSize\" type=\"xs:integer\"/>\n<xs:element name=\"StartRow\" type=\"xs:integer\"/>\n\n<xs:element name=\"DataTable\">\n <xs:complexType>\n <xs:sequence>\n <xs:element ref=\"Row\" maxOccurs=\"unbounded\"/>\n </xs:sequence>\n </xs:complexType>\n</xs:element>\n\n<xs:element name=\"Row\">\n <xs:complexType>\n <xs:sequence>\n <xs:element ref=\"Column\" maxOccurs=\"unbounded\"/>\n <xs:attribute name=\"id\" use=\"required\" type=\"xs:integer\"/>\n </xs:sequence>\n </xs:complexType>\n</xs:element>\n\n<xs:element name=\"Column\">\n <xs:complexType>\n <xs:simpleContent>\n <xs:extension base=\"xs:string\">\n <xs:attribute name=\"id\" use=\"required\"/>\n </xs:extension>\n </xs:simpleContent>\n </xs:complexType>\n</xs:element>\n</xs:schema>\n\nThe interface definition language (IDL) allows access to XML description documents for each noun and verb combination. For example, the **add subscriber** command generates a matching XML document that defines the element and attributes of this command. The IDL allows command processing based on a well-formed but unverified XML document.\n\nThe IDL allows command access to supported media gateway (MGW) devices. The command strings do not follow the XML access format defined in the schema. The CIS supports MGW command strings that are native to the MGW internal command structure.\n\nAll XML documents that originate in the BTS 10200 are dynamically generated. This includes all command description documents.\nManagedObject\n\nA ManagedObject has one element, the MOAttribute. A ManagedObject also has two attributes: the Id of the ManagedObject and the Verb. The Id represents the object on which some action is to be taken. The Verb indicates the action to be taken. For example, subscriber, or termination is a valid id. This is a required attribute.\n\nThe following list describes the various parts of the ManagedObject and their values:\n\n- **Id**—This attribute represents the object on which to take some action.\n- **Verb**—This attribute defines the action to take on a given ManagedObject. This is a required attribute and is composed of character data.\n- **MOAttribute**—The ManagedObject can contain none, one, or more MOAttributes. It has one attribute named Id. This character data acts as a label for the element. The order of these elements does not imply any specific behavior. They are arbitrarily listed.\n- **Required**—This subelement has two values, true and false.\n- **Type**—This subelement defines whether the MOAttribute has a single value, multiple values, or is a text. The multiple or single options imply that a list of choices is offered in the permitted element.\n- **Default**—This subelement is informational. It indicates the default value for the MOAttribute.\n- **Width**—This subelement indicates the total field width of the data. For example, if the MOAttribute is a description, this indicates the length of the description.\n- **HelpText**—This subelement offers a brief text to indicate the nature of the MOAttribute.\n- **Permitted**—This subelement specifies the possible values or ranges for the MOAttribute.\n- **Parser**—This subelement indicates what type of validation is required. There is a single attribute for this subelement. The attribute is an Id field constructed of character data. The subelements are listed below:\n - **JavaScript**—This subelement indicates a possible JavaScript to perform validation or regular expression matching.\n - **RegExp**—This subelement defines the regular expression in character data format.\n\nRequest\n\nThe Request schema consists of one element, containing none, one, or more Entry elements, and two attributes and their values.\n\nThe following list describes the various parts of the schema and its values:\n\n- **Noun**—This attribute defines the item on which some operation is requested. This is expressed as character data.\n- **Verb**—This attribute defines the action to perform on the \"Noun\" attribute. This is expressed as character data.\n\nThe Entry element is allowed to be empty. It can also contain two attributes. These attributes are defined as follows:\n\n- **Key**—This is the id value derived from the MOAttribute in the ManagedObject. It is expressed as character data.\nChapter 2 Extensible Markup Language Processing\n\nCORBA Interface Servant Adapter Implementation\n\n- **Value**—This is the client-derived value to assign to the key specified above. The Value is expressed as character data. It should also conform to the subelements in MOAttribute from which this key/value pair was derived.\n\nReply\n\nThe Reply schema defines the structure of returned data generated in response to a Request. The Reply contains three elements and no attributes. These elements are defined as follows:\n\n- **Status**—The Reply contains one Status element. It has two possible values. Either true or false is applied to this element.\n\n- **Reason**—The Reason element contains character data. This element explains the cause for an error in processing a command or returns a success indication.\n\n- **DataTable**—This element has one attribute and one subelement, which are defined below. This element is used as the container for data that results from the execution of a request. Each Reply can contain a DataTable element.\n - **Row**—This subelement defines a single complete item of data. A DataTable can contain one or more Row subelements. A Row has one attribute. This character data defines the row ID. The ID is always a sequential value based on the number of returned rows. The id attribute is required.\n - **Col**—Each Row contains a subelement known as a Col. This subelement has one attribute. The value of the element is expressed as character data. The attribute for Col is id. It is expressed as a character value. This is the same id value used in the MOAttribute. This is a required attribute.\n\nCORBA Interface Servant Adapter Implementation\n\nThe CIS is an adapter implementation that specifies an external interface. This section provides more detail about the structure of the document interchange between the CIS program and a client-side program. One global issue for the external interface is that all documents covered here are defined as well-formed but not verified. This means that the schema is not an embedded part of the XML document. When the schema are embedded, parser packages can be used to validate the structure of the document. However, this impedes the transition to XML schemas, should schemas be desired by other customers. The client side can still use the schema, included in this document, to perform validation.\n\nCisco BTS 10200 Softswitch IDL Code\n\nThis section presents an example of the system IDL file for the CORBA adapter (CAD) interface in the BTS 10200. This IDL applies to BTS 10200, Release 4.x.\n\n```idl\n// Copyright (c) 2002, 2006 by Cisco Systems, Inc.\n//=========================================================\n//\n// Name: bts10200.idl\n// Author: A. J. Blanchard\n// Description: This is the IDL for the entire provisioning infrastructure of the\n// BTS 10200. The text strings are all XML well-formed documents. The\n// current procedure is to maintain separate schema(s). This allows later\n// migration to schemas and away from schema for document validation.\n//=========================================================\n```\n// All commands are expressed as XML documents. The template document for\n// each NOUN/VERB pair is accessible from the a separate method. This XML\n// interface is table oriented and follows the same nomenclature and syntax\n// as the other BTS 10200 adapter interfaces.\n\n#ifndef bts10200_idl\n#define bts10200_idl\n\n// Set up modules to match java package tree for the OAM&P\nmodule cad {\n\ntypePrefix cad \"oam.sswitch.com\";\n\n// Exceptions\n\nexception CadExceptions {\n long error_code;\n string error_string;\n};\n\ninterface Bts10200_Security {\n\n // Create a session key.\n void login(in string name,\n in string password,\n out string key)\n raises(CadExceptions);\n\n // Destroy a session key.\n void logout(in string key)\n raises(CadExceptions);\n}; // end Bts10200_Security\n\ninterface Bts10200 {\n\n // Fetch a command (noun/verb) XML document\n void getCommandDoc(in string noun,\n in string verb,\n in string key,\n out string xml_doc)\n raises(CadExceptions);\n\n // Fetch an Extended command (noun/verb) XML document - with foreign keys\n void getExtCommandDoc(in string noun,\n in string verb,\n in string key,\n out string xml_doc)\n raises(CadExceptions);\n\n}; // end Bts10200\n\ninterface Macro {\n\n // Issue a command XML document (add, change, delete, show)\n void request(in string xml_request,\n in string key,\n out string xml_reply)\n raises(CadExceptions);\n\n}; // end Bts10200\n\ninterface Macro {\n\n // Process a Macro Command XML document (add, change, delete, show)\n void execute(in string request,\n in string key,\n out string reply)\n raises(CadExceptions);\n\n}; // end Macro\n\n}; // end cad\n\n#endif // end bts10200_idl\nThe Proxy software is an extension in the CORBA Software Developer’s kit (SDK) package that allows several new features to be integrated into the client application. The Proxy software is also designed to work exclusively with the new and revised SSL or secure CORBA interface to the BTS 10200.\n\nThe feature capabilities are:\n\n- **Abstraction of redundant management interfaces on a single BTS 10200 Element Management System (EMS) node.** Each EMS has two physical network interface cards (NICs) available for provisioning, and the CORBA/SSL package utilizes both of these interfaces by binding object instances separately to each interface. The Proxy probes each of these interfaces and determines which interface is functioning or if both interfaces are functioning. The first interface to return the requested BTS 10200 object is declared the primary interface and is used exclusively for transactions. The CORBA protocol IIOP/SSLIOP requires a consistent conversation over a single interface so “load sharing” on these interfaces in a given connection is not possible.\n\n- **Abstract the redundancy of the EMS from the client application.** Many client applications do not fully account for the duplex nature of the BTS 10200 and as a result must exercise some complex reinitialization if the EMS requires a manual switchover or failover. This is time intensive and likely to produce errors. The Proxy allows the abstraction such that the objects returned from the interface fail and a new access of the Proxy returns the corrected (newly ACTIVE) EMS objects. CORBA in the BTS 10200 Release 6.0.x unbinds its objects from the NameService and terminates current login sessions in the event of a failover. As a result, the Proxy continues to probe the NameService for changes on both the ACTIVE and STANDBY EMS nodes to sense a failover. Application clients detect this using a PERMISSION_DENIED error from CORBA or related CORBA COMM error. This release of the BTS 10200 does not contain a Notification Service, so there is no asynchronization notification.\n\n- **Ability to abstract multiple BTS 10200 instances or “complexes” as well.** Each complex must have a unique identifier such as a CLLI code, sensor-id, or the original CORBA site-id to determine which BTS 10200 is being referenced. This ID is used in the Proxy logic as a unique key or locator to find the object and connection information for a particular BTS 10200. This allows a single instance of the Proxy to manage access to multiple BTS 10200s (currently to several hundred). This does not preclude the use of other instances of the Proxy being used in the same network and even other instances of the Proxy talking to the same set of BTS 10200 complexes. There is no requirement in the Proxy for mutual exclusion.\n\n- **Fully use of both management interfaces on the EMS for redundancy.** If no virtual IP is deployed, the NameService and the CORBA application utilize both management interfaces on each EMS.\nSecure Socket Layer Support\n\nThis chapter describes the Common Object Request Broker Architecture (CORBA) Secure Socket Layer (SSL) support.\n\n\nThe SAS protocol exchanges its protocol elements in the service context of the General Inter-ORB Protocol (GIOP) request and reply messages that are communicated over a connection-based transport. The protocol is intended to be used in environments where transport layer security, such as that available using SSL/transport layer security (TLS) or Internet Inter-ORB Protocol (IIOP) over SSL (SSLIOP), provides message protection (that is, integrity and or confidentiality) and server-to-client authentication. The protocol provides client authentication, delegation, and privilege functionality that can be applied to overcome corresponding deficiencies in an underlying transport. The SAS protocol facilitates interoperability by serving as the higher-level protocol under which secure transports can be unified. The CIS implementation of SAS provides the following:\n\n- Secure interoperability predicated on the use of a common transport-layer security mechanism, such as that provided by SSL/TLS.\n- Message protection as necessary that is provided by the transport layer to protect GIOP input and output request arguments.\n- Target-to-client authentication is provided by the transport layer to identify the target.\n- Transport-layer security ensures that the client does not have to issue a preliminary request to establish a confidential association with the intended target.\n- Support for clients that cannot perform authentication by using transport-layer security mechanisms; the SAS protocol provides client authentication above the transport layer.\n- To support the formation of security contexts using GIOP service context, the SAS protocol requires at least one message in each direction to establish a security context.\n- Support for security contexts that exist only for the duration of a single request/reply pair.\n- Support for security contexts that can be reused for multiple request/reply pairs.\nThis implementation is provided through a module extension supplied in the OpenORB CORBA distribution.\n\nSystem Context for System Security Extensions\n\nThis section describes the system context for system security extensions. The system security extensions consist of the SSL module for CORBA combined with the exchange of security certificates. Figure 4-1 provides an overview of the components of the BTS 10200 that are affected by the system security extensions. The exception is the base Solaris OS platform.\n\nDependencies\n\nThis section defines the dependencies for the application components in the Security Extension feature. The dependencies are largely based on external components.\n\nReduced Solaris Image\n\nThere is no specific dependency for this application component. However, the dependency is based on the security needs of the BTS 10200.\n\nJava Implementation of SSL\n\nThe CIS application program depends on the OpenORB implementation of the SSL component module for the CORBA Security Support. This OpenORB module in turn requires the Java implementation of the JSSE or Java Secure Sockets from Sun Microsystems.\nCertificate and Key Password\n\nThis section describes the certificate and the key password for SSL CORBA. The primary feature of SSL CORBA is encrypted transport. This implementation uses a public-keyed, self-signed certificate only and all users have the same key password.\n\nThis section also describes the directory structure where the key store, trust store, and certificate reside for SSL CORBA and the naming conventions that must be adhered to for these files. In the BTS 10200, the certificate and key stores are delivered in the BTS 10200 CIS package. They are located at\n\n```\n/opt/BTScis/cert\n```\n\nThe certificate and key stores are also available in the CORBA SDK package BTSxsdk located at\n\n```\n/opt/BTSxsdk/cert\n```\n\nThe trust store and key store must be named as follows:\n\n```\nbts10200_keystore bts10200_truststore\n```\n\nThe mandatory key password that is Chillan (this is case sensitive).\n\nWhen you use the cis-install.sh script to install CORBA, SSLIOP enabled is the default setting. The client system cannot get in without using the aforementioned key password, key store, and certificate. The key store and trust store must be on both Element Management Systems (EMSs), because there is no automatic redundancy.\n\n**Note**\n\nThe following commands build the key and trust stores on the BTS 10200 and on the client side. Although they are built and deployed by default in the BTS 10200 and in the BTSxsdk, they can be rebuilt or replaced by hand. This is not a recommended procedure at this time.\n\nPassword: Chillan\n\n**Step 1** Generate keys (validity 8 years):\n\n```\nkeytool -genkey -alias bts10200 -keyalg RSA -validity 2840 -keystore bts10200_keystore\n```\n\n**Step 2** Export a certificate:\n\n```\nkeytool -export -alias bts10200 -keystore bts10200_keystore -rfc -file bts10200.cer\n```\n\n**Step 3** Import the certificate into the truststore:\n\n```\nkeytool -import -alias bts10200 -file bts10200.cer -keystore bts10200_truststore\n```\nTroubleshooting\n\nRevised: July 2010, OL-23043-01\n\nThis chapter describes basic cadexceptions, debug actions, and network configuration procedures.\n\nCadexceptions\n\nThe following basic cadexceptions can be returned. The numbers given in the sample code refer to the text in the explanation. The text is returned if the sample code is used.\n\n**Error Message** No Error\n\n**Explanation** This is a placeholder since 0 (zero) is not an error.\n\n**Sample Code**\n\n```\npublic static final int EM_NONE=0;\n```\n\n**Recommended Action** No action. Not an error.\n\n**Error Message** CIS Error\n\n**Explanation** This error is used for internal processing errors that can be related to ORB interaction or other runtime exceptions.\n\n**Sample Code**\n\n```\npublic static final int EM_ERROR=1;\n```\n\n**Recommended Action** Retry the command. If the problem persists, restart the Name Service and CORBA Adapter as described in the “Modify the CORBA Network Configuration” section.\nError Message CIS No Data\n\nExplanation There was no data to return from a show command. This might not be a “real” error; however, it is cleaner to throw an exception than a NULL object.\n\nSample Code\n```java\npublic static final int EM_NODATA=2;\n```\n\nRecommended Action Verify that there is data for this particular Noun (id) by executing the same command using the CLI. Refer to the Cisco BTS 10200 Softswitch CLI Database for appropriate syntax.\n\nError Message User Security Error\n\nExplanation A fault was found in the user security. This can result from an invalid login (password or username). This can also result from some internal error in the security system that caused a failure during an attempt to validate user identity.\n\nSample Code\n```java\npublic static final int EM_USERSEC=5;\n```\n\nRecommended Action Verify that the username and password are correct and valid for access to the BTS 10200. Cross-check by logging in to the CLI with the same username and password.\n\nError Message Permission Error\n\nExplanation A command was attempted that failed the authorization tests for the command. The user does not have permission to execute this command.\n\nSample Code\n```java\npublic static final int EM_PERMISSION=6;\n```\n\nRecommended Action Verify that the user has the appropriate command privilege to execute the request. Cross-check by executing the same command using the CLI and the same user. Refer to the Cisco BTS 10200 Softswitch CLI Database for command privilege information.\n\nError Message Error Message: Block Error\n\nExplanation All provisioning on the switch is blocked because the BTS 10200 is in a maintenance mode. The command might be perfectly well formed and the connection valid.\n\nSample Code\n```java\npublic static final int EM_BLOCK=7;\n```\n\nRecommended Action Try again later.\nError Message Linkage Error\n\nExplanation The linkage failed.\n\nSample Code\npublic static final int EM_LINKAGE=10;\n\nRecommended Action This is an installation error. Call Cisco TAC.\n\nError Message Exception In Initializer Error\n\nExplanation The initialization failed.\n\nSample Code\npublic static final int EM_INIT=11;\n\nRecommended Action Retry the command again. If the problem persists, restart the Name Service and CORBA Adapter as described in the “Modify the CORBA Network Configuration” section.\n\nError Message Class Not Found Exception\n\nExplanation Class cannot be located\n\nSample Code\npublic static final int EM_NOTFOUND=12;\n\nRecommended Action Verify that the CLASSPATH is set up and all jar files exist where specified in the CLASSPATH. The CLASSPATH is set up in /opt/BTScis/bin/cis3 and /opt/ems/bin/Runtime.sh on the EMS.\n\nError Message Illegal Access Exception\n\nExplanation Class or initializer is not accessible.\n\nSample Code\npublic static final int EM_ACCESS=13;\n\nError Message Instantiation Exception\n\nExplanation Thrown if this class represents an abstract class, an interface, an array class, a primitive type, or void; or if the instantiation fails for some other reason.\n\nSample Code\npublic static final int EM_INSTANCE=14;\n\nRecommended Action Verify that the CLASSPATH is set up and all jar files exist where specified in the CLASSPATH. The CLASSPATH is set up in /opt/BTScis/bin/cis3 and /opt/ems/bin/Runtime.sh on the EMS.\nError Message Security Exception\n\nExplanation There is no permission to create a new instance.\n\nSample Code\npublic static final int EM_SECURITY=15;\n\nRecommended Action Verify that the CORBA adapter is running as root. Verify by performing the following command on the EMS: `ps -ef | grep cis3 and not the user`.\n\nError Message Invalid Request Exception\n\nExplanation Request is not valid or cannot be initialized.\n\nSample Code\npublic static final int EM_REQUEST=16;\n\nRecommended Action Verify that the XML request is syntactically correct according to the BTS 10200 standard.\n\nError Message Invalid Noun Exception\n\nExplanation Command noun is not found or is invalid.\n\nSample Code\npublic static final int EM_NOUN=17;\n\nRecommended Action Verify that the Noun (id) in the request is valid and correct for the current software release of the BTS 10200. Cross-check by executing the same command using CLI on the EMS. Refer to the Cisco BTS 10200 Softswitch CLI Database for syntax information.\n\nError Message Invalid Verb Exception\n\nExplanation Command verb is not found or is invalid.\n\nSample Code\npublic static final int EM_VERB=18;\n\nRecommended Action Verify that the Verb in the request is valid and correct for the current software release of the BTS 10200. Cross-check by executing the same command using the CLI on the EMS. Refer to the Cisco BTS 10200 Softswitch CLI Database for syntax information.\nError Message SQL Exception\n\nExplanation Thrown if the database cannot be accessed, if the constraints are violated, if there is a conflict with another table, if there is a resource issue, or any other Oracle-related cause.\n\nSample Code\n\n```java\npublic static final int EM_DATABASE=19;\n```\n\nRecommended Action Verify that the relational databases are currently running on the EMSs. Verify by using the following commands:\n\n1. `ps -ef | grep mysqld`. Verify there’s a process running.\n2. As root, perform a `nodestat` and verify that the Oracle database is running.\n\nIf either are not running, refer to the Cisco BTS 10200 Operations and Maintenance Manual to restart these processes.\n\nError Message Invalid Value Exception\n\nExplanation A parameter value exceeds the range or some other restriction like text length or pick-list.\n\nSample Code\n\n```java\npublic static final int EM_VALUE=20;\n```\n\nRecommended Action Verify that all the values within the XML request conform to the restrictions for those values. Cross-check by executing the same command with the same values using the CLI.\n\nError Message Invalid Key Exception\n\nExplanation An invalid key or token was used to describe some data value.\n\nSample Code\n\n```java\npublic static final int EM_KEY=21;\n```\n\nRecommended Action Verify that all keys and values within the XML request are valid. Cross-check by executing the same command with the same values using the CLI.\n\nError Message Missing Parameter Exception\n\nExplanation One or more required parameters were not included in the command parameter data.\n\nSample Code\n\n```java\npublic static final int EM_PARAM=22;\n```\n\nRecommended Action Verify that all mandatory keys and values are valid. Cross-check by executing the same command with the same values using the CLI.\nModify the CORBA Network Configuration\n\nIn previous releases, the operator was asked for either an IP address or hostname. In this release, the CORBA Installation automatically selects VIP (Virtual IP) if the VIP is configured. Otherwise, the first Management IP address is selected. This requires adding the hostname on the client machine. The following procedure can also be used to modify the name usage in the BTS 10200. In most cases, it is better to change to an IP address to prevent name resolution issues in the client-side network.\n\nNote\n\nThe hostname/IP address is used as part of the interoperable object reference (IOR) that is sent to the client side. That is why the name/IP address must resolve and route to the client.\n\nDetermine the hostname or IP address that works best for the client side of the network and perform the following steps to modify the CORBA network configuration:\n\nStep 1\n\nEdit the /opt/BTSsmg/bin/jpm file and modify the following entries to match the desired configuration. For example:\n\n```\n/sbin/ins3 <VIP or EMS Management IP or hostname> /sbin/ins3\n/sbin/cis3_IIOP <VIP or EMS Management IP or hostname> <EMS Management IP #1>\n< EMS Management IP #2> 2>&1 &\n/sbin/cis3_SSLIOP <VIP or EMS Management IP or hostname> <EMS Management IP #1>\n< EMS Management IP #2> 2>&1 &\n```\n\nStep 2\n\nIn the directory /opt/BTSoorb/config/. (a period (.) fully qualifies the domain directory), execute the setConfig.sh script. The XML configuration file is a bundled resource file in the OpenORB architecture. This command updates the JAR files with the modified OpenORB.xml file.\n\nStep 3\n\nGet the process ID and kill the NameService program using the following commands:\n\n```\npss -eaf | grep D_INS\nkill -KILL <pid>\n```\nThe NameService (INS) and CORBA Servant (CIS_IIOIP and CIS_SSIOP) programs restart automatically.\n\n**Step 4** Terminate the Java children using the `ptree` and `kill` commands. Orphaned Java programs can cause unpredictable behavior.\n\n---\n\n**CORBA Cannot Connect to the BTS 10200**\n\nIf CORBA cannot connect to the BTS 10200, client-side hostname resolution might be required to match what was configured in the Element Management System (EMS). Perform the following steps to troubleshoot:\n\n**Step 1** Verify that the IP/hostname used by the client (for CORBA connection) matches the IP/hostname in the `/opt/BTSsmg/bin/jpm` file:\n\n```\n/sbin/ins3 <VIP or EMS Management IP or hostname> /sbin/ins3\n/sbin/cis3_IIOIP <VIP or EMS Management IP or hostname> <EMS Management IP #1>\n< EMS Management IP #2> 2>&1 &\n/sbin/cis3_SSIOP <VIP or EMS Management IP or hostname> <EMS Management IP #1>\n< EMS Management IP #2> 2>&1 &\n```\n\n**Step 2** Add the following arguments to turn on `debug-trace` command to get the debug information on the client-side. These are the Java arguments:\n\n```\n-Dopenorb.debug.trace=DEBUG -Dopenorb.debug.level=HIGH\n```\n\n**Step 3** If the hostname of the EMS server does not resolve, an exception is thrown. If a default name was used such as “priems01” or “priems_nms1”, these names do not resolve in the client network. Uninstall and then reinstall the CORBA package to modify the EMS to accept IP addresses.\n\n---\n\n**CORBA and EPOM Troubleshooting Steps**\n\nThis section describes various procedures for troubleshooting CORBA with the Extensible Provisioning and Operations Manager (EPOM). This section requires a knowledge of UNIX and Java commands.\n\n---\n\n**Caution**\n\nEPOM cannot be co-resident with the EMS.\n\nPerform the following steps when a problem is encountered:\n\n**Step 1** Verify that the CORBA application is running.\n- For non-secure CORBA, use the following command:\n ```\n ps -eaf | grep CIS_IIOIP\n ```\n- For secure CORBA, use the following command:\nps -eaf | grep CIS_SSLIOPI\n\nStep 2 Check the logs for errors or clues.\n- For non-secure CORBA, use the following command:\n more /opt/ems/log/CIS.log\n- For secure CORBA, use the following command:\n more /opt/ems/log/CIS-SSL.log\n\nStep 3 Check the EPOM logs for errors or clues.\n more var/opt/CSCOepom/logs\n\nIf you determine that the problem pertains to how the BTS 10200 CORBA services are configured, perform the following steps:\n\nStep 1 Ensure that the BTS 10200 hostname is provided in the CORBA configuration.\n a. If the hostname is provided, change it to the IP address of the BTS 10200 and restart the CORBA services on the BTS 10200.\n b. If the hostname is not provided, stop and reinstall the CORBA application before doing anything else.\n\nStep 2 Check if ports 683, 684, and 14001 are listening on the BTS 10200 server by using the following commands:\n netstat -a | grep 683\n netstat -a | grep 684\n netstat -a | grep 14001\n\nNote Port 683 is used for non-secure CORBA communication, and port 684 is used for secure CORBA communication.\n\nStep 3 Do a tail -f on the CIS.log on the BTS 10200 server.\n tail -f /opt/ems/log/CIS.log\n\nNote EPOM log files can be found at /var/opt/CSCOepom/logs. Check for trace.log and localhost files on the EPOM server.\n\nStep 4 After clicking on the Config button on the EPOM GUI (you might need to click more than once):\n netstat -a | grep 14001\n netstat -a | grep 683\n netstat -a | grep 684\n\nStep 5 Ensure that the username and password are the same as those you provided when you added the BTS 10200 inventory to EPOM. The username and password are optiuser/optiuser by default. Verify this by logging in to the system using the CLI.\nCORBA/EPOM Special Character Troubleshooting: Subscriber Commands\n\nTable 5-1 shows the CORBA and EPOM responses to special characters in Subscriber commands.\n\n<table>\n<thead>\n<tr>\n<th>Character</th>\n<th>Usage Example</th>\n<th>CORBA/EPOM Response</th>\n</tr>\n</thead>\n</table>\n| ' (single quote) | btsadmin> change subscriber id=x1-6-00-00-ca-ac-ef-98_02;name=Joe' | Error Message BtsException: IDL:oam.sswitch.com/cad/CadExceptions:1.0, org.omg.CORBA.UNKNOWN: Server Exception: Unregistered vendor exception #0 vmcid: 0x0 minor code: 0 completed \nExplanation The single quote is a reserved character for delimiting strings. It is used this way in caller-ID messages to the MTA. A single quote cannot be used in a name because it causes an error in the MTA that is parsing the caller-ID message. |\n| \" (double quote) | btsadmin> change subscriber id=x1-6-00-00-ca-ac-ef-98_02;name=Joe\" | Explanation Invalid parameter value. name=Joe\"; contains one of the following invalid characters: (\"\") \nExplanation The double quote is a reserved character for delimiting strings. It is used this way in caller-ID messages to the MTA. A single quote cannot be used in a name because it causes an error in the MTA that is parsing the caller-ID message. |\n### CORBA/EPOM Special Character Troubleshooting: Subscriber Commands\n\n**Example 1:**\n```\nbtsadmin> change subscriber\n id=x1-6-00-00-ca-ac-ef-98_02;name=Joe;\n```\n```\nReply : Success: Transaction 91466110924297301 was processed.\n```\n```\nbtsadmin> show subscriber id=x1-6-00-00-ca-ac-ef-98_02\n```\n```\nID=x1-6-00-00-ca-ac-ef-98_02\nCATEGORY=INDIVIDUAL\nNAME=Joe\nSTATUS=ACTIVE\nCOUNTRY=USA\nPRIVACY=NONE\nRING_TYPE_DN1=1\nTERM_ID=aaln/S1/1\nMGW_ID=iad-11\nPIC1=NONE\nPIC2=NONE\nPIC3=NONE\nGRP=N\nUSAGE_SENS=Y\n```\n```\nError Message\n```\nID=x1-6-00-00-ca-ac-ef-98_02\nCATEGORY=INDIVIDUAL\nNAME=Joe;\nSTATUS=ACTIVE\nCOUNTRY=USA\nPRIVACY=NONE\nRING_TYPE_DN1=1\nTERM_ID=aaln/S1/1\nMGW_ID=iad-11\nPIC1=NONE\nPIC2=NONE\nPIC3=NONE\nGRP=N\nUSAGE_SENS=Y\n```\n```\nExplanation\n```\nIn the first example, the two semicolons delimit only two null parameters. In the second example, the last parameter is a null parameter terminated by the <enter> key. The <enter> key always terminates the last parameter in the CLI.\n```\n\nSemicolons can terminate a command without parameters between them. Placing the semicolons anywhere else causes the queue to hang.\n\n### Table 5-1 CORBA and EPOM Responses to Special Characters (continued)\n\n<table>\n<thead>\n<tr>\n<th>Character</th>\n<th>Usage Example</th>\n<th>CORBA/EPOM Response</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>; (semicolon)</td>\n<td>Example 1:</td>\n<td>Example 2:</td>\n</tr>\n</tbody>\n</table>\n| | btsadmin> change subscriber\n id=x1-6-00-00-ca-ac-ef-98_02;name=Joe;; |\n| | Reply : Success: Transaction 91466110924297301 was processed. |\n| | btsadmin> show subscriber id=x1-6-00-00-ca-ac-ef-98_02 |\n| | ID=x1-6-00-00-ca-ac-ef-98_02 |\n| | CATEGORY=INDIVIDUAL |\n| | NAME=Joe |\n| | STATUS=ACTIVE |\n| | COUNTRY=USA |\n| | PRIVACY=NONE |\n| | RING_TYPE_DN1=1 |\n| | TERM_ID=aaln/S1/1 |\n| | MGW_ID=iad-11 |\n| | PIC1=NONE |\n| | PIC2=NONE |\n| | PIC3=NONE |\n| |GRP=N |\n| | USAGE_SENS=Y |\n| | SUB_PROFILE_ID=subpf1 |\n| | TERM_TYPE=TERM |\n| | IMMEDIATE_RELEASE=N |\n| | TERMINATING_IMMEDIATE_REL=N |\n| | SEND_BILLING_DN=N |\n| | SEND_BDN_AS_CPN=N |\n| | SEND_BDN_FOR_EMG=N |\n| | Reply : Success: Entry 1 of 1 returned. |\n| | Error Message |\n| | ID=x1-6-00-00-ca-ac-ef-98_02 |\n| | CATEGORY=INDIVIDUAL |\n| | NAME=Joe; |\n| | STATUS=ACTIVE |\n| | COUNTRY=USA |\n| | PRIVACY=NONE |\n| | RING_TYPE_DN1=1 |\n| | TERM_ID=aaln/S1/1 |\n| | MGW_ID=iad-11 |\n| | PIC1=NONE |\n| | PIC2=NONE |\n| | PIC3=NONE |\n| |GRP=N |\n| | USAGE_SENS=Y |\n| | SUBPROFILE_ID=subpf1 |\n| | TERM_TYPE=TERM |\n| | IMMEDIATE_RELEASE=N |\n| | TERMINATING_IMMEDIATE_REL=N |\n| | SEND_BILLING_DN=N |\n| | SEND_BDN_AS_CPN=N |\n| | SEND_BDN FOR EMG=N |\n| | Reply : Success: Entry 1 of 1 returned. |\n### Table 5-1 CORBA and EPOM Responses to Special Characters (continued)\n\n<table>\n<thead>\n<tr>\n<th>Character</th>\n<th>Usage Example</th>\n<th>CORBA/EPOM Response</th>\n</tr>\n</thead>\n</table>\n| % (percent sign) | `btsadmin>change subscriber id=x1-6-00-00-ca-ac-ef-98_02;name=Joe%` | Error Message BtsException: IDL:oam.sswitch.com/cad/CadExceptions:1.0, Invalid parameter value. name=Joe%; Enter at least 1 character, but not more than 32 characters. \nExplanation The percent sign is a wildcard: for example, show subscriber id=x1-6-00% shows all subscribers whose id begins with x1-6-00. Thus the percent sign is a valid character for the subscriber noun, but is not valid when used with the add or change verbs. |\n| - (hyphen) | `btsadmin>change subscriber id=x1-6-00-00-ca-ac-ef-98_02;name=Joe-` | Error Message Success: Transaction 914661231396356901 was processed. \nExplanation The hyphen is a valid character but impacts the way the caller id is displayed. Using this character is not recommended. |\n| _ (underscore) | `btsadmin>change subscriber id=x1-6-00-00-ca-ac-ef-98_02;name=Joe_` | Error Message Failure: NAME cannot contain an _ character \nExplanation The underscore is a valid character but impacts the way the caller id is displayed. Using this character is not recommended. |\n| & | `btsadmin>change subscriber id=x1-6-00-00-ca-ac-ef-98_02;name=Joe&` | Error Message org.omg.CORBA.UNKNOWN: Server Exception: Unregistered vendor exception #0 vmcid: 0x0 minor code: 0 completed \nExplanation The ampersand is a reserved character in XML that causes this transaction to fail when you send it using XML over a CORBA interface. |\n| $#^*(){}| `btsadmin>change subscriber id=x1-6-00-00-ca-ac-ef-98_02;name=Joe!@#$^*(){}|` | Error Message org.omg.CORBA.UNKNOWN: Server Exception: Unregistered vendor exception #0 vmcid: 0x0 minor code: 0 completed \nExplanation The ampersand is a reserved character in XML that causes this transaction to fail when you send it using XML over a CORBA interface. |\n| @#$^*(){}| `btsadmin>change subscriber id=x1-6-00-00-ca-ac-ef-98_02;name=Joe!@#$^*(){}|` | Error Message Successful \nExplanation These characters are valid. |\nCORBA Operations Support System Events\n\nThis section provides the information that you need to monitor and correct Operations Support System events. Table 8-2 lists all Operations Support System events in numerical order and provides a cross reference to each subsection in this section.\n\n<table>\n<thead>\n<tr>\n<th>Event Type</th>\n<th>Event Name</th>\n<th>Event Severity</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>OSS 12</td>\n<td>User Session Count is Approaching Threshold Limit</td>\n<td>WARNING</td>\n</tr>\n<tr>\n<td>OSS 14</td>\n<td>User Session Count Exceeds Major Threshold Limit</td>\n<td>MAJOR</td>\n</tr>\n<tr>\n<td>OSS 16</td>\n<td>Session Has Been Removed by Session Control Policy</td>\n<td>INFO</td>\n</tr>\n<tr>\n<td>OSS 17</td>\n<td>Session Has Been Removed</td>\n<td>INFO</td>\n</tr>\n<tr>\n<td>OSS 19</td>\n<td>Interface Is Active and Operational</td>\n<td>INFO</td>\n</tr>\n<tr>\n<td>OSS 20</td>\n<td>Interface Is Not Started or Not Operational</td>\n<td>MINOR</td>\n</tr>\n<tr>\n<td>OSS 21</td>\n<td>Resource Reset</td>\n<td>INFO</td>\n</tr>\n</tbody>\n</table>\n\nUser Session Count Is Approaching Threshold Limit (OSS 12)\n\nThe “User Session Count is approaching Threshold Limit” warning event indicates that the number of CORBA login sessions is over 90 percent of the maximum number of logins allowed. Remove idle or long duration sessions using the `stop client-session` command to reduce the number of active sessions. You should also check the number of users in the /opt/BTScis/etc/bts.properties file and set it to a higher value to increase the maximum limit. (The maximum number of users has a hard limit of 50.)\n\nUser Session Count Exceeds Major Threshold Limit (OSS 14)\n\nThe “User Session Count Exceeds Major Threshold Limit” alarm indicates that the maximum number of CORBA login sessions has been reached and no new users can log in. Remove idle or long duration sessions using the `stop client-session` command to reduce the number of active sessions. You should also check the number of users in the /opt/BTScis/etc/bts.properties file and set it to a higher value to increase the maximum limit. (The maximum number of users has a hard limit of 50.)\n\nAlternatively, you can use the `add ems-session-control-policy` command to add control policies and to remove any long running CORBA sessions. After taking these actions, try the CORBA login again.\n\nSession Has Been Removed By Session Control Policy (OSS 16)\n\nThe “Session has been removed by Session Control Policy” information event indicates that a CORBA session was removed for violating a control policy. Inspect the event contents in the policy id. Adjust the policy using the `change ems-session-control-policy` command as needed.\nSession Removed But No OOS (16) Returned\n\nIf a CORBA session is removed but no OSS(16) event was returned, the session may have been idle for too long. Check the CORBA log file to verify if the \"Removing idle user session from the server. Session Detail:\" message appeared at the time the session was removed. Adjust the idle.timeout in /opt/BTScis/etc/bts.properties file to a higher value if needed.\n\nSession Has Been Removed (OSS 17)\n\nThe Session Has Been Removed event serves as an information alert that the session has been removed. The primary cause of the informational alert is that the session was removed because it was idle over the timeout limit.\n\nInterface Is Active and Operational (OSS 19)\n\nThe Interface Is Active and Operational event serves as an informational alert that the application interface is active and operational. The event is informational only and no further action is required.\n\nInterface Is Not Started or Not Operational (OSS 20)\n\nThe Interface Is Not Started or Is Not Operational alarm (minor) indicates that application interface has failed to start or is not operational. To troubleshoot and correct the cause of the alarm, restart the application interface.\n\nResource Reset (OSS 21)\n\nThe Resource Reset event serves as an informational alert that the resource has been reset. The event is informational only and no further action is required.\n\nError Messages\n\nThe following error messages can be returned. The number given in the sample code refers to the text in the explanation. The text is returned if the sample code is used.\n\n**Error Message** Password Aging Warning\n\n**Explanation** This exception indicates that the user’s password will expire in a few days. Login is successful.\n\n**Sample Code** public static final int EM_PW_WARN = 3;\n\n**Recommended Action** This exception is informational. The login was successful. No action to take. If desired, change the password using the loginResetPassword() API instead of the loginWithStatus() API to log in and change the password.\nError Message Password Expired Error\n\nExplanation This exception indicates that the user's password has expired. Login was rejected.\n\nSample Code public static final int EM_PW_EXP = 4;\n\nRecommended Action Change the password using the `loginResetPassword()` API to log in and change the password.\n\nAlarms\n\nThe following alarms might be returned by this feature.\n\nOSS (12)\n\nTo monitor and correct the cause of the event, refer to the “User Session Count Is Approaching Threshold Limit (OSS 12)” section.\n\nDESCRIPTION User Session count is approaching threshold limit\nSEVERITY WARNING\nTHRESHOLD 100\nTHROTTLE 0\nDATAWORDS Session Type—STRING [16]\n Session Maximum Limit—STRING [3]\n Session Current Usage—STRING [3]\n Session Usage Percentage—STRING [3]\nPRIMARY CAUSE The user session usage has reached allowed limit.\nPRIMARY ACTION Use the `report client_session` command to view all login sessions. Use the `stop client_session` command to remove idle sessions.\n\nOSS (14)\n\nTo monitor and correct the cause of the event, refer to the “User Session Count Exceeds Major Threshold Limit (OSS 14)” section.\n\nDESCRIPTION User session count exceeds major threshold limit\nSEVERITY MAJOR\nTHRESHOLD 100\nTHROTTLE 0\nChapter 5 Troubleshooting\n\nCORBA Operations Support System Events\n\nDATAWORDS Session Type—STRING [16]\n Session Maximum Limit—STRING [3]\n Session Current Usage—STRING [3]\n Session Usage Percentage—STRING [3]\n\nPRIMARY CAUSE The user session usage has reached allowed limit.\n\nPRIMARY ACTION Use the report client_session command to view all login sessions. Use the stop client_session command to remove idle sessions.\n\nOSS (16)\n\nTo monitor and correct the cause of the event, refer to the “Session Has Been Removed By Session Control Policy (OSS 16)” section.\n\nDESCRIPTION Session has been removed by Session Control Policy\n\nSEVERITY INFO\n\nTHRESHOLD 100\n\nTHROTTLE 0\n\nDATAWORDS Policy ID—STRING [64]\n Session Type—STRING [16]\n User ID—STRING [16]\n Session Key—STRING [20]\n\nPRIMARY CAUSE Session has been removed by Session Control Policy.\n\nPRIMARY ACTION N/A.\n\nOSS (17)\n\nTo monitor and correct the cause of the event, refer to the “Session Has Been Removed (OSS 17)” section.\n\nDESCRIPTION Session Has Been Removed\n\nSEVERITY INFO\n\nTHRESHOLD 100\n\nTHROTTLE 0\nOSS (19)\n\nTo monitor and correct the cause of the event, refer to the “Interface Is Active and Operational (OSS 19)” section.\n\nDESCRIPTION Interface is Active and Operational\nSEVERITY INFO\nTHRESHOLD 100\nTHROTTLE 0\n\nOSS (20)\n\nTo monitor and correct the cause of the event, refer to the “Interface Is Not Started or Not Operational (OSS 20)” section.\n\nDESCRIPTION Interface Is Not Started or Is Not Operational\nSEVERITY MINOR\nTHRESHOLD 100\nTHROTTLE 0\n\nDATAWORDS\nSession Type - STRING [16]\nUser ID - STRING [16]\nSession Key - STRING [20]\n\nPRIMARY CAUSE\nThe session was removed since it was idle over the timeout limit.\n\nPRIMARY ACTION N/A.\nOSS (21)\n\nTo monitor and correct the cause of the event, refer to the “Resource Reset (OSS 21)” section.\n\n<table>\n<thead>\n<tr>\n<th>DESCRIPTION</th>\n<th>Resource Reset</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>SEVERITY</td>\n<td>INFO</td>\n</tr>\n<tr>\n<td>THRESHOLD</td>\n<td>100</td>\n</tr>\n<tr>\n<td>THROTTLE</td>\n<td>0</td>\n</tr>\n<tr>\n<td>DATAWORDS</td>\n<td>Resource Type - STRING [40]</td>\n</tr>\n<tr>\n<td></td>\n<td>Resource Instance - STRING [40]</td>\n</tr>\n<tr>\n<td>PRIMARY CAUSE</td>\n<td>The resource has been reset.</td>\n</tr>\n<tr>\n<td>PRIMARY ACTION</td>\n<td>N/A.</td>\n</tr>\n</tbody>\n</table>\nXML Description Documents\n\nRevised: July 2010, OL-23043-01\n\nThis appendix provides examples of the XML description documents.\n\nSubscriber Noun and Add Verb\n\nThe following sample XML description document provides an example of the subscriber noun and add verb.\n\n```xml\n<ManagedObject Verb=\"add\" id=\"subscriber\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:noNamespaceSchemaLocation=\"ManagedObject.xsd\">\n <MOAttribute id=\"dn1\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>14</Width>\n <HelpText>Enter at least 1, but not more than 14 characters from the following set: 0123456789-, .</HelpText>\n <Label>Dn1</Label>\n <Parser id=\"GenericDNParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n </MOAttribute>\n <MOAttribute id=\"tg\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n <Label>Tg</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n </MOAttribute>\n <MOAttribute id=\"policy_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>16</Width>\n <HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n <Label>Policy Id</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n </MOAttribute>\n</ManagedObject>\n```\n<Label>POLICY_ID</Label>\n<Parser id=\"TextParser\">\n<JavaScript>TBD</JavaScript>\n<RegExp>TBD</RegExp>\n</Parser>\n</MOAttribute>\n\n<MOAttribute id=\"category\">\n<Required>false</Required>\n<Type>single</Type>\n<Default>[INDIVIDUAL]</Default>\n<Width>15</Width>\n<HelpText>Enter one of the following values: [INDIVIDUAL, MLHG, MLHG_INDIVIDUAL, MLHG_PREF_INDIV, CTXG, CTXG_INDIVIDUAL, PBX, CTXG_TG, CTXG_MLHG, RACF, IVR]</HelpText>\n<Permitted>[INDIVIDUAL, MLHG, MLHG_INDIVIDUAL, MLHG_PREF_INDIV, CTXG, CTXG_INDIVIDUAL, PBX, CTXG_TG, CTXG_MLHG, RACF, IVR]</Permitted>\n</MOAttribute>\n\n<MOAttribute id=\"ss_number\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>11</Width>\n<HelpText>Enter a Social Security Number in the form ###-##-#### where # is digit from 0-9.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"ctxg_id\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>16</Width>\n<HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"name\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>32</Width>\n<HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"mlhg_pref_list_id\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>16</Width>\n<HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n</MOAttribute>\nAppendix A XML Description Documents\n\nSubscriber Noun and Add Verb\n\n</Parser>\n</MOAttribute>\n\n<MOAttribute id=\"address2\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n <Label>Address2</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"address1\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n <Label>Address1</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"city\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>16</Width>\n <HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n <Label>City</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"terminating_immediate_rel\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[N]</Default>\n <Width>3</Width>\n <HelpText>Enter a boolean value of Y for yes or N for no.</HelpText>\n <Label>Terminating Immediate Release</Label>\n <Parser id=\"BooleanParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"billing_dn\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 1, but not more than 32 characters from the following set: \n{0123456789-}.</HelpText>\n <Label>Billing Dn</Label>\n <Parser id=\"GenericDNParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"language\">\n<MOAttribute id=\"email\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>64</Width>\n <HelpText>Enter an email address in the form text@text where text is a set of characters with no spaces.</HelpText>\n <Label>Email</Label>\n <Parser id=\"EmailParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"mlhg_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>16</Width>\n <HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n <Label>MLHG ID</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"tgn_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>8</Width>\n <HelpText>Enter a number from 0 to 99999999.</HelpText>\n <Label>Trunk Group Number ID</Label>\n <Parser id=\"DecimalParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"mgw_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 0 characters, but not more than 32 characters.</HelpText>\n <Label>Media Gateway ID</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"status\">\n <Required>false</Required>\n <Type>single</Type>\n <Default>[ACTIVE]</Default>\n</MOAttribute>\n<MOAttribute id=\"Status\">\n <Type>text</Type>\n <Default>[\"ACTIVE\", \"TEMP_OOS\", \"TEMP_DISCONNECTED\", \"TEMP_UNAVAILABLE\"]</Default>\n <Width>17</Width>\n <HelpText>Enter one of the following values: [ACTIVE, TEMP_OOS, TEMP_DISCONNECTED, TEMP_UNAVAILABLE]</HelpText>\n <Label>Status</Label>\n <Permitted>[ACTIVE, TEMP_OOS, TEMP_DISCONNECTED, TEMP_UNAVAILABLE]</Permitted>\n</MOAttribute>\n\n<MOAttribute id=\"term_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n <Label>Termination ID</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"usage_sens\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[\"Y\"]</Default>\n <Width>3</Width>\n <HelpText>Enter a boolean value of Y for yes or N for no.</HelpText>\n <Label>Usage Sens</Label>\n <Parser id=\"BooleanParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"ID\">\n <Required>true</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>30</Width>\n <HelpText>Enter at least 1 character, but not more than 30 characters.</HelpText>\n <Label>ID</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"grp\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[\"N\"]</Default>\n <Width>3</Width>\n <HelpText>Enter a boolean value of Y for yes or N for no.</HelpText>\n <Label>Grp</Label>\n <Parser id=\"BooleanParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"sub_profile_id\">\n <Required>true</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>16</Width>\n <HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n <Label>Sub Profile Id</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n<MOAttribute id=\"country\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[USA]</Default>\n <Width>16</Width>\n <HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n <Label>Country</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"cos_restrict_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>16</Width>\n <HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n <Label>COS Restrict ID</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"qos_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>16</Width>\n <HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n <Label>QOS ID</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"term_type\">\n <Required>false</Required>\n <Type>single</Type>\n <Default>[TERM]</Default>\n <Width>5</Width>\n <HelpText>Enter one of the following values: [TERM, TG, ROUTE, RG]</HelpText>\n <Label>TERM TYPE</Label>\n <Permitted>[TERM, TG, ROUTE, RG]</Permitted>\n</MOAttribute>\n\n<MOAttribute id=\"ring_type_dn1\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[1]</Default>\n <Width>1</Width>\n <HelpText>Enter a number from 1 to 3.</HelpText>\n <Label>Ring Type Dn1</Label>\n <Parser id=\"DecimalParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"immediate_release\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[N]</Default>\n <Width>3</Width>\n <HelpText>Enter one of the following values: [N, Y, A]</HelpText>\n <Label>Immediate Release</Label>\n <Parser id=\"ImmediateReleaseParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\nAppendix A XML Description Documents\n\n<MOAttribute id=\"sip_url\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Width>32</Width>\n<HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"zipcode\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Width>10</Width>\n<HelpText>Enter at least 1 character, but not more than 10 characters.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"pic3\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Width>4</Width>\n<HelpText>Enter a PIC value as four numeric characters, NPIC, or NONE.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"pic2\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Width>4</Width>\n<HelpText>Enter a PIC value as four numeric characters, NPIC, or NONE.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"privacy\">\n<Required>false</Required>\n<Type>single</Type>\n<Default>NONE</Default>\n<Width>4</Width>\n<HelpText>Enter one of the following values: [FULL, NAME, NONE]</HelpText>\n</MOAttribute>\nForeign Key Relationships\n\nThe following sample XML extended format description document contains the foreign key relationships for a given command.\n\n```xml\n<ManagedObject Verb=\"add\" id=\"subscriber\"\nxmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\nxsi:noNamespaceSchemaLocation=\"ManagedObject.xsd\">\n <MOAttribute id=\"dn1\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>14</Width>\n <HelpText>Enter at least 1, but not more than 14 characters from the following set: {0123456789-}.</HelpText>\n <Label>Dn1</Label>\n <Parser id=\"GenericDNParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n </MOAttribute>\n <MOAttribute id=\"tg\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n <Label>Tg</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n </MOAttribute>\n <MOAttribute id=\"policy_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n <Label>Policy Id</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n </MOAttribute>\n</ManagedObject>\n```\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>16</Width>\n<HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n<Label>POLICY_ID</Label>\n<Parser id=\"TextParser\">\n<JavaScript>TBD</JavaScript>\n<RegExp>TBD</RegExp>\n</Parser>\n</MOAttribute>\n\n<MOAttribute id=\"category\">\n<Required>false</Required>\n<Type>single</Type>\n<Default>[INDIVIDUAL]</Default>\n<Width>15</Width>\n<HelpText>Enter one of the following values: [INDIVIDUAL, MLHG, MLHG_INDIVIDUAL, MLHG_PREF_INDIV, CTXG, CTXG_INDIVIDUAL, PBX, CTXG_TG, CTXG_MLHG, RACF, IVR].</HelpText>\n<Label>Category</Label>\n</MOAttribute>\n\n<MOAttribute id=\"ss_number\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>11</Width>\n<HelpText>Enter a Social Security Number in the form ###-##-#### where # is digit from 0-9.</HelpText>\n<Label>Ss Number</Label>\n<Parser id=\"SocSecParser\">\n<JavaScript>TBD</JavaScript>\n<RegExp>TBD</RegExp>\n</Parser>\n</MOAttribute>\n\n<MOAttribute id=\"ctxg_id\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>16</Width>\n<HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n<Label>Ctxg Id</Label>\n<Parser id=\"TextParser\">\n<JavaScript>TBD</JavaScript>\n<RegExp>TBD</RegExp>\n</Parser>\n</MOAttribute>\n\n<MOAttribute id=\"mlhg_pref_list_id\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>32</Width>\n<HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n<Label>MLHG Pref List Id</Label>\n<Parser id=\"TextParser\">\n<JavaScript>TBD</JavaScript>\n<RegExp>TBD</RegExp>\n</Parser>\n</MOAttribute>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<Required>false</Required>\n<Type>text</Type>\n<Default>null</Default>\n<MOAttribute id=\"Billing_Dn\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 1, but not more than 32 characters from the following set: (0123456789-). </HelpText>\n <Parser id=\"GenericDNParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"language\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>16</Width>\n <HelpText>Enter at least 1 character, but not more than 16 characters. </HelpText>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"email\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>64</Width>\n <HelpText>Enter an email address in the form text@text where text is a set of characters with no spaces. </HelpText>\n <Parser id=\"EmailParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"mlhg_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>16</Width>\n <HelpText>Enter at least 1 character, but not more than 16 characters. </HelpText>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n <Fk id=\"MLH_PREF_LIST_PK\">\n <Noun>mlhg_pref_list</Noun>\n <Param>mlhg_id</Param>\n </Fk>\n</MOAttribute>\n\n<MOAttribute id=\"tgn_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>8</Width>\n <HelpText>Enter a number from 0 to 99999999. </HelpText>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n <Fk id=\"MLHG_PK\">\n <Noun>mlhg</Noun>\n <Param>id</Param>\n </Fk>\n</MOAttribute>\n<Parser id=\"DecimalParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n</Parser>\n\n<Fk id=\"TRUNK_GRP_PK\">\n <Noun>trunk_grp</Noun>\n <Param>id</Param>\n</Fk>\n\n<MOAttribute id=\"mgw_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 0 characters, but not more than 32 characters.</HelpText>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n <Fk id=\"TERMINATION_PK\">\n <Noun>termination</Noun>\n <Param>mgw_id</Param>\n </Fk>\n <Fk id=\"MGW_PK\">\n <Noun>mgw</Noun>\n <Param>id</Param>\n </Fk>\n</MOAttribute>\n\n<MOAttribute id=\"status\">\n <Required>false</Required>\n <Type>single</Type>\n <Default>[ACTIVE]</Default>\n <Width>17</Width>\n <HelpText>Enter one of the following values: [ACTIVE, TEMP_OOS, TEMP_DISCONNECTED, TEMP_UNAVAILABLE].</HelpText>\n <Label>Status</Label>\n <Permitted>[ACTIVE, TEMP_OOS, TEMP_DISCONNECTED, TEMP_UNAVAILABLE]</Permitted>\n</MOAttribute>\n\n<MOAttribute id=\"term_id\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>32</Width>\n <HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n <Fk id=\"TERMINATION_PK\">\n <Noun>termination</Noun>\n <Param>id</Param>\n </Fk>\n</MOAttribute>\n\n<MOAttribute id=\"usage_sens\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[Y]</Default>\n <Width>3</Width>\n <HelpText>Enter a boolean value of Y for yes or N for no.</HelpText>\n <Label>Usage Sens</Label>\n <Parser id=\"BooleanParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n<MOAttribute id=\"id\">\n<Required>true</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>30</Width>\n<HelpText>Enter at least 1 character, but not more than 30 characters.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"grp\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[N]</Default>\n<Width>3</Width>\n<HelpText>Enter a boolean value of Y for yes or N for no.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"sub_profile_id\">\n<Required>true</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>16</Width>\n<HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"country\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[USA]</Default>\n<Width>16</Width>\n<HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"cos_restrict_id\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>16</Width>\n<HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n</MOAttribute>\n<RegExp>TBD</RegExp>\n</Parser>\n<Pk id=\"COST_RESTRICT_PK\">\n<Noun>cos_restrict</Noun>\n</Pk>\n</MOAttribute>\n\n<MOAttribute id=\"qos_id\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>16</Width>\n<HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"term_type\">\n<Required>false</Required>\n<Type>single</Type>\n<Default>[TERM]</Default>\n<Width>5</Width>\n<HelpText>Enter one of the following values: [TERM, TG, ROUTE, RG]</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"ring_type_dn1\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[1]</Default>\n<Width>1</Width>\n<HelpText>Enter a number from 1 to 3.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"immediate_release\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[N]</Default>\n<Width>3</Width>\n<HelpText>Enter a boolean value of Y for yes or N for no.</HelpText>\n</MOAttribute>\n\n<MOAttribute id=\"sip_url\">\n<Required>false</Required>\n<Type>text</Type>\n<Default>[null]</Default>\n<Width>32</Width>\n<HelpText>Enter at least 1 character, but not more than 32 characters.</HelpText>\n</MOAttribute>\n<MOAttribute id=\"zipcode\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>10</Width>\n <HelpText>Enter at least 1 character, but not more than 10 characters.</HelpText>\n <Label>Zipcode</Label>\n <Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"pic3\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>4</Width>\n <HelpText>Enter a PIC value as four numeric characters, NPIC, or NONE.</HelpText>\n <Label>Pic3</Label>\n <Parser id=\"PicParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"pic2\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>4</Width>\n <HelpText>Enter a PIC value as four numeric characters, NPIC, or NONE.</HelpText>\n <Label>Pic2</Label>\n <Parser id=\"PicParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"privacy\">\n <Required>false</Required>\n <Type>single</Type>\n <Default>[NONE]</Default>\n <Width>4</Width>\n <HelpText>Enter one of the following values: [FULL, NAME, NONE].</HelpText>\n <Label>Privacy</Label>\n <Permitted>[FULL, NAME, NONE]</Permitted>\n</MOAttribute>\n\n<MOAttribute id=\"pic1\">\n <Required>false</Required>\n <Type>text</Type>\n <Default>[null]</Default>\n <Width>4</Width>\n <HelpText>Enter a PIC value as four numeric characters, NPIC, or NONE.</HelpText>\n <Label>Pic1</Label>\n <Parser id=\"PicParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n </Parser>\n</MOAttribute>\n\n<MOAttribute id=\"state\">\n <Required>false</Required>\n <Type>text</Type>\nForeign Key Relationships\n\n<Default>[null]</Default>\n<Width>16</Width>\n<HelpText>Enter at least 1 character, but not more than 16 characters.</HelpText>\n<Label>State</Label>\n<Parser id=\"TextParser\">\n <JavaScript>TBD</JavaScript>\n <RegExp>TBD</RegExp>\n</Parser>\n</MOAttribute>\n</ManagedObject>\nThis appendix describes the XML test drivers.\n\n**XML Request Batch File**\n\nThe following example of an XML/CORBA interface test driver executes an XML request batch file built as a CLI script. This allows compatibility with older CLI scripts used to provision the system.\n\n```java\npackage com.sswitch.oam.drv;\n\nimport java.lang.*;\nimport java.io.*;\nimport java.util.*;\nimport java.text.*;\n// XML Stuff\nimport org.apache.ecs.xml.*;\nimport org.apache.ecs.*;\nimport org.w3c.dom.*;\nimport org.xml.sax.*;\nimport org.apache.xml.serialize.*;\n// BTS Interface Code objects...\nimport com.sswitch.oam.cad.*;\nimport com.sswitch.oam.xml.*;\nimport com.sswitch.oam.util.*;\nimport com.sswitch.oam.ccc.*;\n\n/**\n * XmlBatch.java\n * Copyright (c) 2002, 2003 by Cisco Systems, Inc.\n * --Test driver for the XML/CORBA interface...\n * This test driver executes a batch file built as a CLI script as XML\n * requests. This allows compatibility with the older CLI scripts used to\n * provision the system. Note that this example can be built with the\n * provided tool \"oo-cc\" this simple script creates the correct CLASSPATH\n * and invokes the compiler with the correct options. Also, the \"oo-idl\"\n * tool can be used to generate the correct IDL output.\n * @author A. J. Blanchard\n * @version 3.0\n */\n\npublic class XmlBatch {\n```\n/*\n * Class private data\n */\nprivate String [] objArgs;\nprivate CorbaXmlIntf objBts;\n\nprivate File objFile;\nprivate RandomAccessFile objFileHandle;\n\n/**\n * Generic Constructor for the test driver.\n */\nprotected XmlBatch(String[] args)\n{\n // Initialize the ORB.\n objArgs = args;\n objBts = new CorbaXmlIntf(args);\n return;\n}\n\n/**\n * This is the main method for the application.\n */\npublic static void main(String[] args)\n{\n // // Verify that the argument match what is expected...\n // oo-run XmlRequest <CLI Request File> \\\n // -ORBopenorb.config=\"./OpenORB.xml\"\n // if(args.length < 2)\n // {\n // System.out.println(\"%nStart program as: oo-run XmlRequest <XML Request File>\n // -ORBopenorb.config=\"./OpenORB.xml\"%n\");\n // System.exit(0);\n // }\n XmlBatch me = new XmlBatch(args);\n me.go();\n return;\n}\n\n/**\n * This is the primary execution method for the object. It performs the \n * actual request and calls for the print of the reply.\n */\nprotected void go()\n{\n // // Log into the target machine with generic optiuser\n // // try {\n // objBts.connect();\n // System.out.println(\"BTS10200 Login successful...\"%n\");\n // } catch (Exception e) {\n // System.out.println(\"Exception in login = \" + e);\n // System.exit(1);\n // }\n // // Read in the file and send request...\ntry {\n String reply = \"\";\n openCLI();\n while(true) {\n CommandParser parser = new CommandParser();\n String cmd = readCLI(); // Fetch the request file....\n if(cmd==null) break;\n if(cmd.startsWith(\"#\") || cmd.length()==0) continue;\n else {\n // Issue request to BTS 10200\n reply = objBts.request(parser.toXML(cmd));\n System.out.println(\"RETURN VALUE: \");\n parser.prettyPrint(reply);\n }\n } // end while(1)\n closeCLI();\n // Clean up and logout\n objBts.disconnect();\n} catch (CadExceptions ce) {\n System.out.println(\"CIS Command Exception: CODE=\\\"+ce.error_code +\\\"\\n\\\"+ce.error_string);\" + ce.printStackTrace();\n} catch (Exception e) {\n System.out.println(\"Batch Command Exception = \\\" + e); e.printStackTrace();\n} return;\n} // end go()\n\n/**\n * Open the input file for reading. This allows the read method to suck\n * a line at a time of the CLI style input.\n */\nprotected void openCLI() {\n try {\n objFile=new File(objArgs[1]);\n objFileHandle=new RandomAccessFile(objFile,\"r\");\n }\n catch(Exception e) {\n // In the event of an error. just bail out of the program\n System.out.println(\"Error in processing file:\\n\"+e.toString());\n System.exit(1);\n }\n}\n\n/**\n * This is the method that closes and clean up after a file has been\n * processed.\n */\nprotected void closeCLI() throws java.io.IOException\n\nOL-23043-01\nCLI to CORBA XML Transaction\n\nThe following example of a test driver executes a normal CLI command but processes it as a CORBA XML transaction.\n\n```java\nimport java.lang.*;\nimport java.io.*;\nimport java.util.*;\nimport java.text.*;\n// XML Stuff\nimport org.apache.ecs.xml.*;\nimport org.apache.ecs.*;\nimport org.w3c.dom.*;\nimport org.xml.sax.*;\nimport org.apache.xml.serialize.*;\n// BTS Utility Code objects...\nimport com.sswitch.oam.cad.*;\nimport com.sswitch.oam.xml.*;\nimport com.sswitch.oam.util.*;\nimport com.sswitch.oam.ccc.*;\n/**\n * XmlCli.java\n * Copyright (c) 2002, 2003 by Cisco Systems, Inc.\n */\n```\n* --Test driver for the XML/CORBA interface...\n* This test driver executes a normal CLI command and processes the request\n* as a CORBA XML transaction. The reply is then displayed. I am no as\n* concerned with complex data show(s) as with the ability to issue\n* provisioning commands. Note that this example can be built with the\n* provided tool \"oo-cc\" this simple script creates the correct CLASSPATH\n* and invokes the compiler with the correct options. Also, the \"oo-idl\"\n* tool can be used to generate the correct IDL output.\n* @author A. J. Blanchard\n* @version 3.0\n*/\n\npublic class XmlCli {\n\n /*\n * Class private data\n */\n private String[] objArgs;\n private CorbaXmlIntf objBts;\n\n /**\n * Generic Constructor for the test driver.\n */\n protected XmlCli(String[] args)\n {\n // Initialize the BTS ORB interface object.\n objArgs = args;\n objBts = new CorbaXmlIntf(args);\n return;\n }\n\n /**\n * This is the main method for the application.\n */\n public static void main(String[] args)\n {\n // Verify that the argument match what is expected...\n // oo-run XmlCli -ORBopenorb.config=\"./OpenORB.xml\"\n if (args.length < 1)\n {\n System.out.println(\"Start program as: oo-run XmlCli\n -ORBopenorb.config=\"./OpenORB.xml\"\");\n System.exit(0);\n }\n XmlCli me = new XmlCli(args);\n me.go();\n return;\n }\n\n /**\n * This is the primary execution method for the object. It performs the\n * actual request and calls for the print of the reply.\n */\n protected void go()\n {\n \n //\n// Log into the target machine with generic optiuser\n//\ntry {\n objBts.connect();\n System.out.println(\"BTS10200 Login successful...\");\n} catch (Exception e) {\n System.out.println(\"Exception in login = \" + e);\n System.exit(1);\n}\n\n// Read the file and send request...\n//\ntry {\n while(true)\n {\n openCLI(); // Put out the prompt...\n CommandParser parser = new CommandParser();\n String cmd = readCLI().trim(); // Fetch the request file...\n String reply = \"\";\n if(cmd.equals(\"\"))\n continue;\n if(cmd.equals(\"exit\"))\n break;\n else\n {\n // Issue request to BTS 10200\n reply = objBts.request(parser.toXML(cmd));\n System.out.println(\"RETURN VALUE: \");\n parser.prettyPrint(reply);\n }\n } // end while(true)\n\n closeCLI(); // Clean up and logout\n objBts.disconnect();\n} catch (CadExceptions ce) {\n System.out.println(\"CIS Command Exception: CODE=\\\"+ce.error_code + \"\\n\\\"+ce.error_string); \n ce.printStackTrace();\n} catch (Exception e) {\n System.out.println(\"CIS Command Exception: \\n\"+e.toString());\n //e.printStackTrace();\n} return;\n} // end go()\n\n/**\n * Open the input file for reading. This allows the read method to suck\n * a line at a time of the CLI style input.\n */\nprotected void openCLI()\n{\n System.out.print(\"CORBA-CLI> \");\n return;\n}\n\n/**\n* This is the method that closes and clean up after a file has been\n* processed.\n*/\nprotected void closeCLI() throws java.io.IOException\n{\n System.out.println(\"\\n Bye...\");\n return;\n}\n\n/**\n* Read in the file provided as the request. Just exit on errors. Don't\n* worry about throwing an error exception.\n*/\nprotected String readCLI() throws java.io.IOException\n{\n int temp=0;\n int idx=0;\n byte [] buf= new byte[256];\n\n while(true)\n {\n temp = System.in.read();\n if(temp==10) // <ENTER Key>\n break;\n buf[idx++]=(byte) temp;\n }\n return new String(buf);\n}\n\n//=====================================================================\n// Tools and utilities...\n//=====================================================================\n\n} // end XmlCli\nSample CORBA Client Package (BTSxsdk) Implementation\n\nRevised: July 2010, OL-23043-01\n\nThis appendix details a sample implementation of a CORBA Client Package (BTSxsdk). BTSxsdk is a Software Development Kit (SDK) that implements a sample CORBA client for connecting the BTS 10200 through the CORBA adapter. BTSxsdk package is automatically installed onto the Element Management System (EMS) when the CORBA adapter (BTScis package) installs. Use this SDK as a starting point to develop custom client programs. Successfully running this SDK also verifies the correct installation of the CORBA adapter on an EMS.\n\nBTSxsdk Java Capabilities\n\nThis section describes some capabilities of the BTSxsdk.\n\nSDK\n\nThe Software Developers Kit (SDK) includes the following capabilities:\n\n- Provides both secured and non-secured CORBA interface access using port 684 for the Cognitronics Privacy Manager application.\n- Provides CORBA access to the active EMS within a BTS 10200 system. The BTS 10200 CORBA interface exclusively binds to the active EMS.\n- Provides a single management interface to all BTS 10200 systems.\n- Supports both nonsecured and secured access to the BTS 10200 CORBA interfaces.\n- Enables a single BTS 10200 CORBA interface to customer OSS applications to redirect requests from the OSS to two redundant BTS 10200 systems.\n- Requires no predetermined NIC interface during BTS 10200 installation. Previous BTS 10200 installation required operators to specify a NIC address in the dual NIC interface configuration. Now the BTS 10200 CORBA interface dynamically binds to the VIP or a NIC address in a dual NIC configuration.\nPrerequisites\n\nJava Classes\n\nJava classes provide the following capabilities:\n- Support access to multiple BTS sites using CLLI code\n- Conceal redundant EMS nodes (for ACTIVE access only)\n- Conceal redundant NIC(s) on each EMS node\n- Track the state of the CIS application on each EMS\n- Supply a single set of IOR references to the BTS 10200 client applications\n\nMost of the capabilities are supplied in a series of classes to abstract access to the BTS 10200. This simplifies the management of objects and connections to the BTS 10200.\n\nCORBA Interface Servant\n\nExtensions\n\nThe following extensions were added for the CORBA Interface Servant (CIS) application. While the CIS application engine is running, it applies these extensions.\n- Bind individual IP addresses to Name Service(s) on each EMS\n- Unbind if EM01 is STANDBY, shuts down, or fails over\n- Stop processing requests when not in ACTIVE EM01\n\nDual Mode Operations\n\nDual mode operations apply. Both nonsecure and secure provisioning work only on the active EMS. A switchover from either a failure or a manual request causes the objects to unbind and current connections to break. As a result, queries to the standby side produce Java exceptions.\n\nPrerequisites\n\nThe BTSxsdk package is automatically installed onto the EMS when the CORBA adapter installs. If you install the BTSxsdk on another machine, the following prerequisites apply when you implement the BTSxsdk package:\n- The BTSxsdk package must be installed on a UNIX machine that is in the same intranet as the EMS where the CORBA adapter is installed.\n- Java Development Kit (JDK) 1.4.1_01 or later is installed. In this document the assumption is that the JDK is installed under /usr/java.\n\nUsers must be familiar with the Cisco BTS 10200 Softswitch Command Line Interface (CLI) adapter commands.\nOpenORB Settings\n\nThe OpenORB package requires a modification to the JDK. It updates properties in the JDK to enable it to point to the OpenORB implementation for the CORBA interface objects. There are two ways to modify JDK for OpenORB:\n\n- The BTS 10200 package BTSoorb automatically updates the JDK during installation.\n- Type the following commands in the order given:\n - cd /opt/BTSxsdk/oorb/lib\n - java -jar openorb-1.3.1.jar\n\nBuild the BTSxsdk\n\nThe BTSxsdk package is prebuilt in Java. A build is not necessary if sample files are not modified. If necessary, perform the following steps to build a sample client application:\n\n<table>\n<thead>\n<tr>\n<th>Step 1</th>\n<th>Go to the BTSxsdk directory.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>cd /opt/BTSxsdk</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Step 2</th>\n<th>Perform export.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>export PROJECTDIR=<code>pwd</code></td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Step 3</th>\n<th>Perform export.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>export JAVA_HOME=/usr/java</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Step 4</th>\n<th>Perform make all.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>./bin/make all</td>\n</tr>\n</tbody>\n</table>\nRun BTSxsdk\n\nTo run the sample CLI client application, perform the following steps:\n\n---\n\n**Step 1**\nGo to the bin directory.\n```\ncd /opt/BTSxsdk/bin\n```\n\n**Step 2**\nIssue the following command to run the BTSxsdk.\n\n- **a.** To connect to the non-secure CORBA server, enter the command:\n ```\n ./bts-cli <Active EMS IP> -n <username> -p <password>\n ```\n The “Active EMS IP” can be one of the following:\n - One of the active EMS management IP addresses\n - VIP\n - Active EMS DNS name\n\n- **b.** To connect to the secure CORBA server, enter the command:\n ```\n ./bts-cli-secure <Active EMS Mgmt IP> -n <username> -p <password>\n ```\n The “active EMS Mgmt IP” must be one of the active EMS management IP addresses.\n\nA CLI-like interface appears. Issue a test CLI command such as `show sub; limit=1`—the XML response displays on the screen.\n\n---"}}},{"rowIdx":94,"cells":{"id":{"kind":"string","value":"5f328f62829dd36490dc0ddeb7e94bf1c988136e"},"text":{"kind":"string","value":"Minimal Session Types\n\nAlen Arslanagić\nUniversity of Groningen, The Netherlands\n\nJorge A. Pérez\nUniversity of Groningen, The Netherlands\n\nErik Voogd\nUniversity of Groningen, The Netherlands\n\nAbstract\n\nSession types are a type-based approach to the verification of message-passing programs. They have been much studied as type systems for the π-calculus and for languages such as Java. A session type specifies what and when should be exchanged through a channel. Central to session-typed languages are constructs in types and processes that specify sequencing in protocols.\n\nHere we study minimal session types, session types without sequencing. This is arguably the simplest form of session types. By relying on a core process calculus with sessions and higher-order concurrency (abstraction-passing), we prove that every process typable with usual (non minimal) session types can be compiled down into a process typed with minimal session types. This means that having sequencing constructs in both processes and session types is redundant; only sequentiality in processes is indispensable, as it can precisely codify sequentiality in types.\n\nOur developments draw inspiration from work by Parrow on behavior-preserving decompositions of untyped processes. By casting Parrow’s results in the realm of typed processes, our results reveal a conceptually simple formulation of session types and a principled avenue to the integration of session types into languages without sequencing in types.\n\n2012 ACM Subject Classification Theory of computation → Type structures; Theory of computation → Process calculi; Software and its engineering → Concurrent programming structures; Software and its engineering → Message passing\n\nKeywords and phrases Session types, process calculi, π-calculus.\n\nDigital Object Identifier 10.4230/LIPIcs.ECOOP.2019.11\n\nCategory Pearl\n\nRelated Version Full version with proofs and further examples: http://arxiv.org/abs/1906.03836\n\nSupplement Material ECOOP Artifact Evaluation approved artifact available at http://dx.doi.org/10.4230/DARTS...\n\nFunding Work partially supported by the Netherlands Organization for Scientific Research (NWO) under the VIDI Project No. 016.Vidi.189.046 (Unifying Correctness for Communicating Software).\n\nAcknowledgements We are grateful to the anonymous reviewers for their remarks and questions. Pérez is also with CWI, Amsterdam and the NOVA Laboratory for Computer Science and Informatics (FCT grant NOVA LINCS PEst/UID/CEC/04516/2013), Universidade Nova de Lisboa, Portugal.\n\n1 Introduction\n\nSession types are a type-based approach to the verification of message-passing programs. A session type specifies what and when should be exchanged through a channel; this makes them a useful tool to enforce safety and liveness properties related to communication correctness. Session types have had a significant impact on the foundations of programming languages [15], but also on their practice [1]. In particular, the interplay of session types and object-oriented\n11:2 Minimal Session Types\n\nlanguages has received much attention (cf. [8, 7, 14, 11, 2, 18, 25]). In this work, our goal is to understand to what extent session types can admit simpler, more fundamental formulations. This foundational question has concrete practical ramifications, as we discuss next.\n\nIn session-typed languages, **sequencing** constructs in types and processes specify the intended structure of message-passing protocols. In the session type \\( S := ?(\\text{Int}); ?(\\text{Int}); !(\\text{Bool}); \\text{end} \\), sequencing (denoted ‘;’) allows us to specify a protocol for a channel that first receives (?), then sends (!) a Boolean, and finally ends. As such, \\( S \\) could type a service that checks for integer equality. Sequencing in types goes hand-in-hand with sequencing in processes, which is specified using prefix constructs (denoted ‘;’). The \\( \\pi \\)-calculus process \\( P = s!(x_1).s?(x_2).s!(b) \\) is an implementation of the equality service: it first expects two values on name \\( s \\), then outputs a Boolean on \\( s \\), and finally stops. Thus, name \\( s \\) in \\( P \\) conforms to type \\( S \\). Session types can also specify sequencing within labeled choices and recursion; these typed constructs are also in close match with their respective process expressions.\n\nOriginally developed on top of the \\( \\pi \\)-calculus for the analysis of message-passing protocols between exactly two parties [12], session types have been extended in many directions. We find, for instance, multiparty session types [13] and extensions with dependent types, assertions, exceptions, and time (cf. [6, 15] for surveys). All these extensions seek to address natural research questions on the expressivity and applicability of session types theories.\n\nHere we address a different, if opposite, question: is there a minimal formulation of session types? This is an appealing question from a theoretical perspective, but seems particularly relevant to the practice of session types: identifying the “core” of session types could enable their integration in languages whose type systems do not have advanced constructs present in session types (such as sequencing). For instance, the Go programming language offers primitive support for message-passing concurrency; it comes with a static verification mechanism which can only enforce that messages exchanged along channels correspond with their declared payload types—it cannot ensure essential correctness properties associated to the structure of protocols. This observation has motivated the development of advanced static verification tools based on session types for Go programs [22, 21].\n\nThis paper identifies an elementary formulation of session types and studies its properties. We call them **minimal session types**: these are session types without sequencing. That is, in session types such as ‘!\\( U \\); \\( S \\)’ and ‘?\\( U \\); \\( S \\)’, we decree that \\( S \\) can only correspond to \\( \\text{end} \\), the type of the terminated protocol.\n\nAdopting this elementary formulation entails dispensing with sequencing, which is one of the most distinctive features of session types. While this may appear as a far too drastic restriction, it turns out that it is not: our main result is that for every process \\( P \\) that is well-typed under standard (non minimal) session types, there is a **process decomposition** \\( \\mathcal{D}(P) \\) that is well-typed using minimal session types. Intuitively, \\( \\mathcal{D}(P) \\) codifies the sequencing information given by the session types (protocols) of \\( P \\) using additional synchronizations. This shows that having sequencing in both types and processes is redundant; only sequencing at the level of processes is truly fundamental. To define \\( \\mathcal{D}(P) \\) we draw inspiration from a known result by Parrow [24], who proved that untyped \\( \\pi \\)-calculus processes can be decomposed as a collection of **trios processes**, i.e., processes with at most three nested prefixes [24].\n\nThe question of how to relate session types with other type systems has attracted interest in the past. Session types have been encoded into generic types [10] and linear types [5, 3, 4]. As such, these prior studies concern the **relative expressiveness** of session types: where the expressivity of session types stands with respect to that of some other type system. In sharp contrast, we study the **absolute expressiveness** of session types: how session types can be explained in terms of themselves. To our knowledge, this is the first study of its kind.\nThe process language that we consider for decomposition into minimal session types is HO, the core process calculus for session-based concurrency studied by Kouzapas et al. [19, 20]. HO is a very small language: it supports abstraction-passing only and lacks name-passing and recursion; still, it is also very expressive, because both features can be expressed in it in a fully abstract way. As such, HO is an excellent candidate for a decomposition. Being a higher-order language, HO is very different from the (untyped, first-order) π-calculus considered by Parrow in [24]. Also, the session types of HO severely constrain the range and kind of conceivable decompositions. Therefore, our results are not an expected consequence of Parrow’s: essential aspects of our decomposition into processes typable with minimal session types are only possible in a higher-order setting, not considered in [24].\n\nSumming up, in this paper we make the following contributions:\n1. We identify the class of minimal session types as a simple fragment of standard session types that retains its absolute expressiveness.\n2. We show how to decompose processes typable with standard session types into processes typable with minimal session types. We prove that this decomposition satisfies a typability result for a rich typed language that includes labeled choices and recursive types.\n3. We develop optimizations of our decomposition that bear witness to its robustness.\n\nThe rest of the paper is organized as follows. §2 summarizes the syntax, semantics, and session type system for HO, the core process calculus for session-based concurrency. §3 presents the decomposition of well-typed HO processes into minimal session types. The decomposition is presented incrementally, starting with a core fragment that is later extended with further features. §4 presents optimizations of the decomposition. §5 elaborates further on related works and §6 concludes. The appendix contains omitted definitions and proofs.\n\n## 2 The Source Language\n\nWe recall the syntax, semantics, and type system for HO, the higher-order process calculus for session-based concurrency studied by Kouzapas et al. [19, 20]. HO is arguably the simplest language for session types: it supports passing of abstractions (functions from names to processes) but does not support name-passing nor process recursion. Still, HO is very expressive: it can encode name-passing, recursion, and polyadic communication via type-preserving encodings that are fully-abstract with respect to contextual equivalence [19].\n\n### 2.1 Syntax and Semantics\n\nThe syntax of names, variables, values, and HO processes is defined as follows:\n\n\\[\n\\begin{align*}\n n, m & ::= a, b \\mid s, \\bar{s} \\\\\n u, w & ::= n \\mid x, y, z \\\\\n V, W & ::= x, y, z \\mid \\lambda x.P \\\\\n P, Q & ::= u!(V).P \\mid u?(x).P \\mid u!l.P \\mid u?\\{l_i : P_i\\}_{i \\in I} \\mid V u \\mid P \\mid Q \\mid (\\nu n)P \\mid 0\n\\end{align*}\n\\]\n\nWe use \\(a, b, c, \\ldots\\) to range over shared names, and \\(s, \\bar{s}, \\ldots\\) to range over session names. Shared names are used for unrestricted, non-deterministic interactions; session names are used for linear, deterministic interactions. We write \\(n, m\\) to denote session or shared names, and assume that the sets of session and shared names are disjoint. The dual of \\(n\\) is denoted \\(\\bar{n}\\); we define \\(\\bar{s} = s\\) and \\(\\bar{a} = a\\), i.e., duality is only relevant for session names. Variables are\n\n---\n\n1 We summarize the content from [19, 20] that concerns HO; the notions and results given in [19, 20] are given for HOπ, a super-calculus of HO.\ndenoted with $x, y, z, \\ldots$. An abstraction $\\lambda x. P$ is a process $P$ with parameter $x$. Values $V, W, \\ldots$ include variables and abstractions, but not names. A tuple of variables $(x_1, \\ldots, x_k)$ is denoted $\\bar{x}$ (and similarly for names and values). We use $\\epsilon$ to denote the empty tuple.\n\nProcesses $P, Q, \\ldots$ include usual $\\pi$-calculus output and input prefixes, denoted $u!(V). P$ and $u?x.P$, respectively. Processes $u \\cdot l.P$ and $u \\cdot \\{l_i : P_i\\}_{i \\in I}$ are selecting and branching constructs, respectively, commonly used in session calculi to express deterministic choices [12]. Process $V u$ is the application which substitutes name $u$ on abstraction $V$. Constructs for inaction $\\mathbf{0}$, parallel composition $P_1 \\parallel P_2$, and name restriction $(\\nu n)P$ are standard. HO lacks name-passing and recursion, but they are expressible in the language (see Exam. 2.1 below).\n\nWe sometimes omit trailing $\\mathbf{0}$'s, so we may write, e.g., $u!(V)$ instead of $u!(V). \\mathbf{0}$. Also, we write $u!(V) P$ and $u?V.P$ whenever the exchanged value is not relevant (cf. Rem. 3.7).\n\nSession name restriction $(\\nu s)P$ simultaneously binds session names $s$ and $\\bar{s}$ in $P$. Functions $fv(P)$, $fn(P)$, and $fs(P)$ denote, respectively, the sets of free variables, names, and session names in $P$, and are defined as expected. If $fv(P) = \\emptyset$, we call $P$ closed. We write $P[\\nu y/x]$ (resp., $P[\\nu y/V]$) for the capture-avoiding substitution of name $u$ (resp., value $V$) for $y$ in process $P$. We identify processes up to consistent renaming of bound names, writing $P \\equiv \\alpha$ for this congruence. We shall rely on Barendregt’s variable convention, which ensures that free and bound names are different in every mathematical context.\n\nThe operational semantics of HO is defined in terms of a reduction relation, denoted $\\rightarrow$. Reduction is closed under structural congruence, denoted $\\equiv$, which is defined as the smallest congruence on processes such that:\n\n\\[\n\\begin{align*}\nP \\mid 0 \\equiv P, & \\\\\nP_1 \\mid P_2 \\equiv P_2 \\mid P_1, & \\\\\n(P_1 \\mid P_2) \\equiv (P_2 \\mid P_1), & \\\\\n(P_1 \\mid P_2) \\parallel (P_3 \\mid P_2) \\equiv (P_3 \\mid P_2) \\mid P_3, & \\\\\n(\\nu n)0 \\equiv 0, & \\\\\nP \\mid (\\nu n)Q \\equiv (\\nu n)(P \\mid Q), & \\quad (n \\notin fs(P)) \\quad P \\equiv Q \\text{ if } P \\equiv \\alpha Q \\end{align*}\n\\]\n\nWe assume the expected extension of $\\equiv$ to values $V$. The reduction relation expresses the behavior of processes; it is defined as follows:\n\n\\[\n\\begin{align*}\n(\\lambda x. P) u & \\rightarrow P[\\nu y/x] & \\text{[App]} \\\\\nn!(V). P \\mid \\pi?x.Q & \\rightarrow P \\mid Q[V/x] & \\text{[Pass]} \\\\\nn \\cdot l_j.Q \\mid \\pi \\cdot \\{l_i : P_i\\}_{i \\in I} & \\rightarrow Q \\mid P_j & \\quad (j \\in I) & \\text{[Sel]} \\\\\nP \\rightarrow P' \\Rightarrow (\\nu n)P & \\rightarrow (\\nu n)P' & \\text{[Res]} \\\\\nP \\rightarrow P' \\Rightarrow P \\parallel Q & \\rightarrow P' \\parallel Q & \\text{[Par]} \\\\\nP \\equiv Q \\rightarrow Q' \\equiv P' & \\Rightarrow P \\rightarrow P' & \\text{[Cong]}\n\\end{align*}\n\\]\n\nRule [App] defines name application. Rule [Pass] defines a shared or session interaction, depending on the nature of $n$. Rule [Sel] is the standard rule for labelled choice/selection. Other rules are standard $\\pi$-calculus rules. We write $\\rightarrow^k$ for a $k$-step reduction, and $\\rightarrow^*$ for the reflexive, transitive closure of $\\rightarrow$.\n\nWe illustrate HO processes and their semantics by means of an example.\n\n**Example 2.1 (Encoding Name-Passing).** HO lacks name-passing, and so the reduction\n\n\\[\nn!(m). P \\mid \\pi?x.Q \\rightarrow P \\mid Q[m/x]\n\\]\n\nis not supported by the language. Still, as explained in [19], name-passing can be encoded in a fully-abstract way using abstraction-passing, by “packing” the name $m$ in an abstraction. Let $[\\ ]$ be the encoding defined as\n\n\\[\n\\begin{align*}\n[n!(m). P] & = n!(\\lambda z. z?x.(x m)). [P] \\\\\nn?x.Q & = n?(y). (\\nu s)(ys \\mid \\pi!(\\lambda x. [Q]))\n\\end{align*}\n\\]\nand as an homomorphism for the other constructs. Reduction (1) can be mimicked as\n\\[\n[n!\\langle x \\rangle.P] | \\pi?\\langle x \\rangle.Q] = n!(\\lambda z. z?\\langle x \\rangle.(x m)).[P] | n!(y).\\langle y s \\| \\pi!\\langle \\lambda x. [Q]\\rangle)\n\\rightarrow [P] | (\\langle y s \\| \\pi!\\langle \\lambda x. [Q]\\rangle)\n\\rightarrow [P] | (\\langle y s \\| \\pi!\\langle \\lambda x. [Q]\\rangle)\n\\rightarrow [P] | (\\langle y s \\| \\pi!\\langle \\lambda x. [Q]\\rangle)\n\\rightarrow [P] | (\\lambda x. [Q]) m\n\\rightarrow [P] | [Q]\\{m/x\\}\n\\]\n\n\\textbf{Remark 2.2 (Polyadic Communication).} HO as presented above allows only for monadic communication, i.e., the exchange of tuples of values with length 1. We will find it convenient to use HO with polyadic communication, i.e., the exchange of tuples of values \\(\\bar{V}\\), with length \\(k \\geq 1\\). In HO, polyadicity appears in session synchronizations and applications, but not in synchronizations on shared names. This entails having the following reduction rules:\n\n\\[\n(\\lambda \\bar{x}. P) \\bar{u} \\rightarrow P\\{\\bar{u}/\\bar{x}\\}\n\\]\n\n\\[\ns!(\\bar{V}). P | \\pi?\\langle \\bar{x} \\rangle.Q \\rightarrow P | Q\\{\\bar{V}/\\bar{x}\\}\n\\]\n\nwhere the simultaneous substitutions \\(P\\{\\bar{u}/\\bar{x}\\}\\) and \\(P\\{\\bar{V}/\\bar{x}\\}\\) are as expected. This polyadic HO can be readily encoded into (monadic) HO [20]: for this reason, by a slight abuse of notation we will often write HO when we actually mean “polyadic HO”.\n\n\\subsection{Session Types for HO}\n\nWe give essential definitions and properties for the session type system for HO, following [20].\n\n\\textbf{Definition 2.3 (Session Types for HO [20]).} Let us write \\(\\phi\\) to denote the process type. The syntax of types for HO is defined as follows:\n\n\\[\nU :: \\ C \\to \\phi \\ | \\ C \\to \\phi\nC :: \\ S \\ | \\ \\langle U \\rangle\nS :: \\ \\text{end} \\ | \\ !\\langle U \\rangle; S \\ | \\ ?\\langle U \\rangle; S \\ | \\ \\oplus \\{ l_i : S_i \\}_{i \\in I} \\ | \\ \\&\\{ l_i : S_i \\}_{i \\in I} \\ | \\ \\mu t. S \\ | \\ t\n\\]\n\nValue types \\(U\\) include \\(C \\to \\phi\\) and \\(C \\to \\phi\\), which denote \\textit{shared} and \\textit{linear} higher-order types, respectively. Shared channel types are denoted \\(\\langle S \\rangle\\) and \\(\\langle U \\rangle\\). Session types, denoted by \\(S\\), follow the standard binary session type syntax [12]. Type \\texttt{end} is the termination type. The output type \\(!\\langle U \\rangle; S\\) first sends a value of type \\(U\\) and then follows the type described by \\(S\\). Dually, \\(?!\\langle U \\rangle; S\\) denotes an input type. The branching type \\&\\{ \\(l_i : S_i\\) \\}_{i \\in I} and the selection type \\(\\oplus\\{ l_i : S_i \\}_{i \\in I}\\) are used to type the branching and selection constructs that define the labeled choice. We assume the recursive type \\(\\mu t. S\\) is guarded, i.e., type \\(\\mu t. t\\) is not allowed.\n\nIn session types theories duality is a key notion: implementations derived from dual session types will respect their protocols at run-time, avoiding communication errors. Intuitively, duality is obtained by exchanging \\(!\\) by \\(?\\) (and vice versa) and \\(\\oplus\\) by \\& (and vice versa), including the fixed point construction. We write \\(S\\) dual \\(T\\) if session types \\(S\\) and \\(T\\) are dual according to this intuition; the formal definition is coinductive, and given in [20].\n\nWe consider shared, linear, and session \\textit{environments}, denoted \\(\\Gamma, \\Lambda, \\text{and } \\Delta\\), resp.:\n\n\\[\n\\Gamma :: = \\emptyset \\ | \\ \\Gamma, x : C \\to \\phi \\ | \\ \\Gamma, u : \\langle U \\rangle \\quad \\Lambda :: = \\emptyset \\ | \\ \\Lambda, x : C \\to \\phi\n\\Delta :: = \\emptyset \\ | \\ \\Delta, u : S\n\\]\nFirst, a session environment \\( \\Delta \\) maps variables and shared names to value types; \\( \\Lambda \\) maps variables to linear higher-order types. While \\( \\Gamma \\) admits weakening, contraction, and exchange principles, both \\( \\Lambda \\) and \\( \\Delta \\) are only subject to exchange. The domains of \\( \\Gamma, \\Lambda, \\) and \\( \\Delta \\) are assumed pairwise distinct. \\( \\Delta \\cdot \\Delta \\) is the disjoint union of \\( \\Delta_1 \\) and \\( \\Delta_2 \\).\n\nWe write \\( \\Gamma \\setminus x \\) to denote \\( \\Gamma \\setminus \\{x : C\\} \\), i.e., the environment obtained from \\( \\Gamma \\) by removing the assignment \\( x : C \\rightarrow \\circ \\), for some \\( C \\). Notations \\( \\Delta \\setminus u \\) and \\( \\Gamma \\setminus x \\) will have expected readings. With a slight abuse of notation, given a tuple of variables \\( \\vec{x} \\), we sometimes write \\( (\\Gamma, \\Delta)(\\vec{x}) \\) to denote the tuple of types assigned to variables in \\( \\vec{x} \\).\n\nThe typing judgements for values \\( V \\) and processes \\( P \\) are denoted\n\n\\[\n\\begin{align*}\n\\Gamma; \\Lambda; \\Delta \\vdash V \\triangleright P & \\quad \\text{and} \\quad \\Gamma; \\Lambda; \\Delta \\vdash P \\triangleright \\circ \\\\\n\\end{align*}\n\\]\n\nFig. 1 shows selected typing rules; see \\([20]\\) for a full account. The shared type \\( C \\rightarrow \\circ \\) is derived using Rule (PROM) only if the value has a linear type with an empty linear environment. Rule (EPROM) allows us to freely use a shared type variable as linear. Abstraction values are typed with Rule (ABS): the type \\( C \\) of an application name \\( u \\) must match the type of the application variable \\( x \\) (\\( C \\rightarrow \\circ \\) or \\( C \\rightarrow \\circ \\)). In Rule (SEND), the type \\( U \\) of value \\( V \\) should appear as a prefix in the session type \\( !(\\langle U \\rangle) \\); \\( S \\) of \\( u \\). Rule (RCV) is its dual. Rules (REQ) and (ACC) type interaction along shared names; the type of the sent/received object \\( V \\) (i.e., \\( U \\)) should match the type of the subject \\( s \\) (\\( \\langle U \\rangle \\)).\n\nTo state type soundness, we require two auxiliary definitions on session environments. First, a session environment \\( \\Delta \\) is balanced (written balanced(\\( \\Delta \\))) if whenever \\( s : S_1, \\vec{x} : S_2 \\in \\Delta \\) then \\( S_1 \\) is dual \\( S_2 \\). Second, we define the reduction relation \\( \\rightarrow \\) on session environments as:\n\n\\[\n\\begin{align*}\n\\Delta, s : !(\\langle U \\rangle) ; S_1, \\vec{x} : ?(\\langle U \\rangle) ; S_2 & \\quad \\rightarrow \\quad \\Delta, s : S_1, \\vec{x} : S_2 \\\\\n\\Delta, s : \\oplus \\{i : S_i\\}_{i \\in I}, \\vec{x} : \\& \\{i : S_i'\\}_{i \\in I} & \\quad \\rightarrow \\quad \\Delta, s : S_k, \\vec{x} : S_k' (k \\in I)\n\\end{align*}\n\\]\n\n\\[\\text{Theorem 2.4 (Type Soundness [20])} \\]\nSuppose \\( \\Gamma; \\emptyset; \\Delta \\vdash P \\triangleright \\circ \\) with balanced(\\( \\Delta \\)). Then \\( P \\rightarrow P' \\) implies \\( \\Gamma; \\emptyset; \\Delta' \\vdash P' \\triangleright \\circ \\) and \\( \\Delta = \\Delta' \\) or \\( \\Delta \\rightarrow \\Delta' \\) with balanced(\\( \\Delta' \\)).\nWe present our approach for a core fragment of λu definitions, including the definition of breakdown function. Then we give our main result:\n\n3.2 The Core Fragment\n\nbranching; an extension that supports names with recursive types is presented in §3.4.\n\nnor recursive types. In §3.3 we shall extend the decomposition functions with selection and composition, and inaction. Hence, this fragment does not have labeled choice and recursion, fragment of several ways in which our developments differ from Parrow’s. In §3.2, we consider a “core fragment” of HO, which contains output and input prefixes, application, restriction, parallel composition, and inaction. Hence, this fragment does not have labeled choice and recursion, nor recursive types. In §3.3 we shall extend the decomposition functions with selection and branching; an extension that supports names with recursive types is presented in §3.4.\n\n3.1 Key Ideas\n\nOur goal is to transform an HO process $P$, typable with the session types in Def. 2.3, into another HO process, denoted $D(P)$, typable using minimal session types (cf. Def. 3.1 below). By means of this transformation on processes, which we call a decomposition, the sequencing in session types for $P$ is codified in $D(P)$ by using additional actions. To ensure that this transformation on $P$ is sound, we must also decompose its session types; our main result says that if $P$ is well-typed under session types $S_1, \\ldots, S_n$, then $D(P)$ is typable using the minimal session types $G(S_1), \\ldots, G(S_n)$, where $G(\\cdot)$ is a decomposition function that “slices” a session type (as in Def. 2.3) into a list of minimal session types (cf. Def. 3.2 below).\n\nTo define the decomposition $D(P)$, in Def. 3.8 we rely on a breakdown function that translates $P$ into a composition of trios processes (or simply trios). A trio is a process with exactly three nested prefixes. Roughly speaking, if $P$ is a sequential process with $k$ nested actions, then $D(P)$ will contain $k$ trios running in parallel: each trio in $D(P)$ will enact exactly one prefix from $P$; the breakdown function must be carefully designed to ensure that trios trigger each other in such a way that $D(P)$ preserves the prefix sequencing in $P$.\n\nWe borrow from Parrow [24] some useful terminology and notation on trios. The context of a trio is a tuple of variables $\\tilde{x}$, possibly empty, which makes variable bindings explicit. We use a reserved set of propagator names (or simply propagators), denoted with $c_k, c_{k+1}, \\ldots$, to carry contexts and trigger the subsequent trio. A process with less than three sequential prefixes is called a degenerate trio. Also, a leading trio is the one that receives a context, performs an action, and triggers the next trio; a control trio only activates other trios.\n\nThe breakdown function works on both processes and values. The breakdown of process $P$ is denoted by $B^3_k(P)$, where $k$ is the index for the propagators $c_k$, and $\\tilde{x}$ is the context to be received by the previous trio. Similarly, the breakdown of a value $V$ is denoted by $V^k_\\emptyset(V)$.\n\nWe present the decomposition of well-typed HO processes (and its associated typability results) incrementally—this is useful to gradually illustrate our ideas and highlight the several ways in which our developments differ from Parrow’s. In §3.2, we consider a “core fragment” of HO, which contains output and input prefixes, application, restriction, parallel composition, and inaction. Hence, this fragment does not have labeled choice and recursion, nor recursive types. In §3.3 we shall extend the decomposition functions with selection and branching; an extension that supports names with recursive types is presented in §3.4.\nThm. 3.11 (Page 13) asserts that if process \\( P \\) is well-typed with standard session types, then \\( \\mathcal{D}(P) \\) is well-typed with minimal session types. This theorem relies crucially on Thm. 3.10 (Page 13), which specifies the way in which the breakdown function preserves typability.\n\n### 3.2.1 Preliminaries\n\nWe start by introducing minimal session types as a fragment of Def. 2.3:\n\n- **Definition 3.1 (Minimal Session Types)**. The syntax of minimal session types for HO is defined as follows:\n\n \\[\n \\begin{align*}\n U & ::= \\tilde{C} \\rightarrow \\diamond \\mid \\tilde{C} \\twoheadrightarrow \\diamond \\\\\n C & ::= M \\mid \\langle U \\rangle \\\\\n M & ::= \\text{end} \\mid !\\langle \\tilde{U} \\rangle; \\text{end} \\mid ?(\\tilde{U}); \\text{end}\n \\end{align*}\n \\]\n\nClearly, this minimal type structure induces a reduced set of typable HO processes. We shall implicitly assume a type system for HO based on these minimal session types by considering the expected specializations of the notions, typing rules, and results summarized in §2.2.\n\nWe now define how to “slice” a session type into a list of minimal session types.\n\n- **Definition 3.2 (Decomposing Session Types)**. Let \\( S \\) be a session type, \\( U \\) be a higher-order type, \\( C \\) be a name type, and \\( \\langle U \\rangle \\) be a shared type, all as in Def. 2.3. The type decomposition function \\( G(\\cdot) \\) is defined as:\n\n \\[\n \\begin{align*}\n G(!\\langle U \\rangle; S) &= \\begin{cases} \n !G(U); \\text{end} & \\text{if } S = \\text{end} \\\\\n !G(U); \\text{end}, G(S) & \\text{otherwise}\n \\end{cases} \\\\\n G(?\\langle U \\rangle; S) &= \\begin{cases} \n ?G(U); \\text{end} & \\text{if } S = \\text{end} \\\\\n ?G(U); \\text{end}, G(S) & \\text{otherwise}\n \\end{cases} \\\\\n G(\\text{end}) &= \\text{end} \\\\\n G(C \\rightarrow \\diamond) &= G(C) \\rightarrow \\diamond \\\\\n G(C \\twoheadrightarrow \\diamond) &= G(C) \\twoheadrightarrow \\diamond \\\\\n G(\\langle U \\rangle) &= \\langle G(U) \\rangle \\\\\n G(S_1, \\ldots, S_n) &= G(S_1), \\ldots, G(S_n)\n \\end{align*}\n \\]\n\nThus, intuitively, if a session type \\( S \\) contains \\( k \\) input/output actions, the list \\( G(S) \\) will contain \\( k \\) minimal session types. We write \\( |G(S)| \\) to denote the length of \\( G(S) \\).\n\n- **Example 3.3**. Let \\( S = ?(\\text{Int}); ?(\\text{Int}); !(\\text{Bool}); \\text{end} \\) be the session type given in §1. Then \\( G(S) \\) is the list of minimal session types given by \\( ?(\\text{Int}); \\text{end}, ?(\\text{Int}); \\text{end}, !(\\text{Bool}); \\text{end} \\). \n\nThe breakdown function \\( B^k(\\cdot) \\) will operate on processes with indexed names (cf. Def. 3.6). Indexes are relevant for session names: a name \\( s_i \\) will execute the \\( i \\)-th action in session \\( s \\). For this reason, to extend the decomposition function \\( G(\\cdot) \\) to typing environments, we consider names \\( u_i \\) in \\( \\Gamma \\) and \\( \\Delta \\). To define the decomposition of environments, we rely on the following notation. Given a tuple of names \\( \\tilde{s} = s_1, \\ldots, s_n \\) and a tuple of (session) types \\( \\tilde{S} = S_1, \\ldots, S_n \\) of the same length, we write \\( \\tilde{s} : \\tilde{S} \\) to denote a list of typing assignments \\( s_1 : S_1, \\ldots, s_n : S_n \\).\nWe define decomposition degree of names. We shall write \\( \\tilde{x} \\) where: \\( k > 0 \\). \\( \\tilde{x} \\) is a tuple of variables, is defined inductively in §3.2.2.\n\nDefinition 3.5 (Degree of a Process and Value). Let \\( P \\) be an HO process. The degree of \\( P \\), denoted \\( |P| \\), is inductively defined as follows:\n\n\\[\n|P| = \\begin{cases} \n|V| + |Q| + 1 & \\text{if } P = u_i!V.Q \\\\\n|Q| + 1 & \\text{if } P = u_i!(y).Q \\text{ or } P = u_i?y.Q \\\\\n|V| + 1 & \\text{if } P = V u_i \\\\\n|P'| & \\text{if } P = (\\nu s : S)P' \\\\\n|Q| + |R| + 1 & \\text{if } P = Q \\mid R \\\\\n1 & \\text{if } P = y u_i \\text{ or } P = 0 \n\\end{cases}\n\\]\n\nThe degree of a value \\( V \\), denoted \\( |V| \\), is defined as follows:\n\n\\[\n|V| = \\begin{cases} \n|P| & \\text{if } V = \\lambda x : C^\\to .P \\\\\n0 & \\text{if } V = \\lambda x : C^\\to .P \\text{ or } V = y \n\\end{cases}\n\\]\n\nWe define an auxiliary function that “initializes” the indices of a tuple of names.\n\nDefinition 3.6 (Name and Process Initialization). Let \\( \\tilde{u} = (a, b, s, s', \\ldots) \\) be a finite tuple of names. We shall write \\( \\text{init}(\\tilde{u}) \\) to denote the tuple \\( (a_1, b_1, s_1, s'_1, \\ldots) \\). We will say that a process has been initialized if all of its names have some index.\n\nRemark 3.7. Recall that we write \\( c_k?() \\) and \\( \\tau_k!() \\) to denote input and output prefixes in which the value communicated along \\( c_k \\) is not relevant. While \\( c_k?() \\) stands for \\( \\langle \\nu x : S \\rangle \\tau_k!() \\), \\( \\tau_k!() \\) stands for \\( \\tau_k!(\\lambda x . 0) \\). Their corresponding minimal types are \\( ?(\\text{end} \\to \\to) ; \\text{end} \\) and \\( ! (\\text{end} \\to \\to) ; \\text{end} \\), which are denoted by \\( ?(\\cdot); \\text{end} \\) and \\( !(\\cdot); \\text{end} \\), respectively.\n\nRecall that \\( P \\) is closed if \\( \\text{fv}(P) = \\emptyset \\). We now define the decomposition of a process.\n\nDefinition 3.8 (Decomposing Processes). Let \\( P \\) be a closed HO process such that \\( \\tilde{u} = \\text{fn}(P) \\). The decomposition of \\( P \\), denoted \\( \\mathcal{D}(P) \\), is defined as:\n\n\\[\n\\mathcal{D}(P) = (\\nu \\tilde{c}) (\\tau_k!() \\cdot 0 \\mid B^k(P\\sigma))\n\\]\n\nwhere: \\( k > 0 \\); \\( \\tilde{c} = (c_k, \\ldots, c_{k+|P|-1}) \\); \\( \\sigma = \\{\\text{init}(\\tilde{u})/\\tilde{u}\\} \\) and the breakdown function \\( B^k(\\cdot) \\), where \\( \\tilde{x} \\) is a tuple of variables, is defined inductively in §3.2.2.\n\nThe bulk of the decomposition of a process is given by the breakdown function, detailed next.\n3.2.2 The Breakdown Function\n\nGiven a context \\( \\overline{x} \\) and a \\( k > 0 \\), the breakdown function \\( B^k_\\overline{x}(\\cdot) \\) is defined on the structure of initialized processes, relying on the breakdown function on values \\( V^k_\\overline{x}(\\cdot) \\). The definition relies on type information; we describe each of its cases next.\n\n**Output** The decomposition of \\( u_i!(V).Q \\) is the most interesting case: an output prefix sends a value \\( V \\) (i.e., an abstracted process) that has to be broken down as well. We then have:\n\n\\[\nB^k_\\overline{x}(u_i!(V).Q) = c_k?(\\overline{x}).u_i!(V^k_{\\overline{x}+1}(V\\sigma)).\\overline{c_{k+1+1}(\\overline{z})} \\mid B^k_\\overline{x+1}(Q\\sigma)\n\\]\n\nProcess \\( B^k_\\overline{x}(u_i!(V).Q) \\) consists of a leading trio that mimics an output action in parallel with the breakdown of the continuation \\( Q \\). The context \\( \\overline{x} \\) must include the free variables of \\( V \\) and \\( Q \\), denoted \\( \\overline{y} \\) and \\( \\overline{z} \\), respectively. These tuples are not necessarily disjoint: variables with shared types can appear free in both \\( V \\) and \\( Q \\). The output object \\( V \\) is then broken down with parameters \\( \\overline{y} \\) and \\( k \\); the latter serves to consistently generate propagators for the trios in the breakdown of \\( V \\), denoted \\( V^k_{\\overline{x}+1}(V\\sigma) \\) (see below for its definition). The substitution \\( \\sigma \\) increments the index of session names; it is applied to both \\( V \\) and \\( Q \\) before they are broken down. We then distinguish two cases:\n\n- If name \\( u_i \\) is linear (i.e., it has a session type) then its future occurrences are renamed into \\( u_{i+1} \\), and \\( \\sigma = \\{u_{i+1}/u_i\\};\n- Otherwise, if \\( u_i \\) is not linear, then \\( \\sigma = \\{\\} \\).\n\nNote that if \\( u_i \\) is linear then it appears either in \\( V \\) or \\( Q \\) and \\( \\sigma \\) affects only one of them. The last prefix in the leading trio activates the breakdown of \\( Q \\) with its corresponding context \\( \\overline{z} \\). To avoid name conflicts with the propagators used in the breakdown of \\( V \\), we use \\( \\overline{c_{k+1+1}} \\), with \\( l = |V| \\) as a trigger for the continuation.\n\nWe remark that the same breakdown strategy is used when \\( V \\) stands for a variable \\( y \\). Since by definition \\( |y| = 0 \\), \\( V^k_\\overline{x}(y) = y \\), and \\( y\\sigma = y \\), we have:\n\n\\[\nB^k_\\overline{x}(u_i!(y).Q) = c_k?(\\overline{x}).u_i!(y).\\overline{c_{k+1+1}(\\overline{z})} \\mid B^k_\\overline{x+1}(Q\\sigma)\n\\]\n\nWe may notice that variable \\( y \\) is not propagated further if it does not appear in \\( Q \\).\n\n**Input** The decomposition of an input prefix is defined as follows:\n\n\\[\nB^k_\\overline{x}(u_i?\\overline{y}Q) = c_k?(\\overline{x}).u_i?\\overline{y}Q.\\overline{c_{k+1+1}(\\overline{z'})} \\mid B^k_\\overline{x+1}(Q\\sigma)\n\\]\n\nwhere \\( \\overline{z'} = \\overline{fV}(Q) \\). A leading trio mimics the input action and possibly extends the context with the received variable \\( y \\). The substitution \\( \\sigma \\) is defined as in the output case.\n\n**Application** The breakdown of \\( V \\) \\( u_i \\) is as follows:\n\n\\[\nB^k_\\overline{x}(V \\ u_i) = c_k?(\\overline{x}).V^k_{\\overline{x}+1}(V) \\overline{m}\n\\]\n\nA degenerate trio receives a context \\( \\overline{x} \\) and then proceeds with the application. We break down \\( V \\) with \\( \\overline{x} \\) as a context since these variables need to be propagated to the abstracted process. We use \\( k + 1 \\) as a parameter to avoid name conflicts. Name \\( u_i \\) is decomposed into a tuple \\( \\overline{m} \\) using type information: if \\( u_i : C \\) then \\( \\overline{m} = (u_i, \\ldots, u_{i+|G(C)|-1}) \\) and so the length of \\( \\overline{m} \\) is \\( |G(C)| \\); each name in \\( \\overline{m} \\) will perform exactly one action. When \\( V \\) is a variable \\( y \\), we have:\n\n\\[\nB^k_\\overline{x}(y \\ u_i) = c_k?(y).y \\overline{m}\n\\]\n\nNotice that by construction \\( \\overline{x} = y \\).\nRestriction We define the breakdown of a restricted process as follows:\n\n\\[ B^{k}_{E}(\\nu s : C)P') = (\\nu \\tilde{s} : \\mathcal{G}(C))B^{k}_{E}(P' \\sigma) \\]\n\nBy construction, \\( \\tilde{x} = \\nu v(P') \\). Similarly as in the decomposition of \\( u_i \\) into \\( \\tilde{m} \\) discussed above, we use the type \\( C \\) of \\( s \\) to obtain the tuple \\( \\tilde{s} \\) of length \\( |G(C)| \\). We initialize the index of \\( s \\) in \\( P' \\) by applying the substitution \\( \\sigma \\). This substitution depends on \\( C \\): if it is a shared type then \\( \\sigma = \\{s/s\\} \\); otherwise, if \\( C \\) is a session type, then \\( \\sigma = \\{\\tilde{m}\\tilde{r}/s\\tilde{r}\\} \\).\n\nComposition The breakdown of a process \\( Q \\mid R \\) is as follows:\n\n\\[ B^{k}_{E}(Q \\mid R) = c_{k'}(\\tilde{x}).x_{k'+1}!\\langle \\tilde{y} \\rangle .x_{k'+1}!(\\tilde{z}) \\mid B^{k+1}_{E}(Q) \\mid B^{k+1}_{E}(R) \\]\n\nA control trio triggers the breakdowns of \\( Q \\) and \\( R \\); it does not mimic any action of the source process. The tuple \\( \\tilde{y} \\subseteq \\tilde{x} \\) (resp. \\( \\tilde{z} \\subseteq \\tilde{x} \\)) collects the free variables in \\( Q \\) (resp. \\( R \\)). To avoid name conflicts, the trigger for the breakdown of \\( R \\) is \\( c_{k+l+1} \\), with \\( l = |Q| \\).\n\nInaction To breakdown \\( \\emptyset \\), we define a degenerate trio with only one input prefix that receives a context that by construction will always be empty, i.e., \\( \\tilde{x} = \\epsilon \\):\n\n\\[ B^{k}_{E}(\\emptyset) = c_{k'}(.).0 \\]\n\nValue In defining the breakdown function for values we distinguish two main cases:\n\n- If \\( V = \\lambda y : C \\rightarrow .P \\), where \\( \\leadsto \\in \\{\\rightarrow, \\rightarrow\\} \\), then we have:\n\n\\[ V^{k}_{R}(\\lambda y : C \\rightarrow .P) = \\lambda \\tilde{y} : \\mathcal{G}(C) \\rightarrow .(\\nu \\tilde{c} ) \\langle \\tilde{r} \\rangle (\\tilde{x}) \\mid B^{k}_{E}(P[y/\\tilde{y}]) \\]\n\nWe use type \\( C \\) to decompose \\( y \\) into the tuple \\( \\tilde{y} \\). We abstract over \\( \\tilde{y} \\); the body of the abstraction is the composition of a control trio and the breakdown of \\( P \\), with name index initialized with the substitution \\( \\{y/\\tilde{y}\\} \\). If \\( \\leadsto \\rightarrow \\rightarrow \\) then we restrict the propagators \\( \\tilde{c} = (c_{k}, \\ldots, c_{k+p_{-1}}) \\); this enables us to type the value in a shared environment. When \\( \\leadsto \\rightarrow \\rightarrow \\) we do not have to restrict the propagators, and \\( \\tilde{c} = \\epsilon \\).\n\n- If \\( V = y \\), then the breakdown function is the identity: \\( V^{k}_{R}(y) = y \\).\n\nTab. I summarizes the definition of the breakdown, spelling out the side conditions involved. We illustrate it by means of an example:\n\n**Example 3.9 (Breaking Down Name-Passing).** Consider the following process \\( P \\), in which a channel \\( m \\) is passed, through which a Boolean value is sent back:\n\n\\[ P = (\\nu u)(u!\\langle m \\rangle .\\pi?!(b).0 \\mid \\pi?(x).x!(\\text{true}).0) \\]\n\n\\( P \\) is not an HO process as it features name-passing. We then use the encoding described in Exam. 2.1 to construct its encoding into HO. We thus obtain \\( [P] = (\\nu u)(Q \\mid R) \\), where\n\n\\[ Q = u!(V).\\pi?!(y).(\\nu s)(y s \\mid \\pi!(\\lambda b.0).0) \\]\n\\[ V = \\lambda z . z?!(x).x m \\]\n\\[ R = \\pi?(y).(\\nu s)(y s \\mid \\pi!(W).0) \\]\n\\[ W = \\lambda x . x!(W').0 \\] with \\( W' = \\lambda z . z?!(x).x \\text{true} \\)\n\nBy Exam. 2.1, we know that \\([\\cdot]\\) requires exactly four reduction steps to mimic a name-passing synchronization. We show here part of the reduction chain of \\([P]\\):\n\n\\[ [P] \\rightarrow^{4} [\\pi?(b).0 \\mid m!(\\text{true}).0] \\rightarrow^{4} 0 \\] (2)\n\nWe will now investigate the decomposition of \\([P]\\) and its reduction chain. First, we use Def. 3.5 to compute \\( |V| = |W'| = 2 \\), and so \\( |W| = 4 \\). Then \\( |Q| = |y s \\mid \\pi!(\\lambda b.0).0| + |V| + 2 = 9 \\), and\nsimilarly, $|R| = 9$. Therefore, $|P| = 19$. Following Def. 3.8, we see that $\\sigma = \\{m_{1}, m_{2.1}, m_{2.2}\\}$, which we silently apply. Using $k = 1$, we then have the decomposition shown in Tab. 2.\n\nTab. 2 we have omitted substitutions that have no effect and trailing $\\mathbf{0}$. The first interesting process appears after synchronizations on $c_{1}, c_{2},$ and $c_{11}$. At that point, the process will be ready to mimic the first action that is performed by $[P]$, i.e., $u_{1}$ will send $V_{2}(V)$, the breakdown of $V$. Next, $c_{12}, c_{13},$ and $c_{14}$ will synchronize, and $V_{2}(V)$ is passed further along, until $s_{1}$ is ready to be applied to it in the breakdown of $R$. At this point, we know that $[P] = \\sim \\gamma_{1}^{1}((\\nu \\tilde{c})P')$, where $\\tilde{c} = (c_{3,1}, \\ldots, c_{10,1}, \\ldots, c_{12,1})$, and\n\n$$P' = c_{3,1}(\\cdot) \\cdot | c_{3,2}(\\cdot) c_{2,1}(\\cdot) \\cdot | c_{2,2}(\\cdot) \\cdot | c_{1,1}(\\cdot) \\cdot | c_{1,2}(\\cdot) \\cdot | c_{1,3}(\\cdot) \\cdot | c_{1,4}(\\cdot) \\cdot | c_{1,5}(\\cdot) \\cdot | c_{1,6}(\\cdot) \\cdot | c_{1,7}(\\cdot) \\cdot | c_{1,8}(\\cdot) \\cdot | c_{1,9}(\\cdot) \\cdot | c_{1,10}(\\cdot) \\cdot$$\n\nAfter $s_{1}$ is applied, the trio guarded by $c_{3}$ will be activated, where $z_{1}$ has been substituted.\n\n<table>\n<thead>\n<tr>\n<th>$P$</th>\n<th>$B_{k}^{+}(P)$</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>$u_{1}(V)Q$</td>\n<td>$c_{k}(\\tilde{x})u_{1}(\\tilde{y})B_{k+1}^{+}(V\\sigma \\cdot \\tilde{x} \\cdot \\tilde{y})</td>\n</tr>\n<tr>\n<td>$\\tilde{y} = \\mathbf{fv}(V), \\tilde{z} = \\mathbf{fv}(Q)$</td>\n<td>$l =</td>\n</tr>\n<tr>\n<td>$\\sigma = {u_{1}+1/u_{1}}$ if $u_{1} : S$</td>\n<td>otherwise</td>\n</tr>\n<tr>\n<td>$u_{2}(y)Q$</td>\n<td>$c_{k}(\\tilde{x})u_{2}(y)B_{k+1}^{+}(\\tilde{x} \\cdot \\tilde{y})</td>\n</tr>\n<tr>\n<td>$\\tilde{x}' = \\mathbf{fv}(Q)$</td>\n<td>$\\sigma = {u_{1}+1/u_{1}}$ if $u_{1} : S$</td>\n</tr>\n<tr>\n<td>$\\sigma = {}$ otherwise</td>\n<td></td>\n</tr>\n<tr>\n<td>$V \\cdot u_{1}$</td>\n<td>$c_{k}(\\tilde{x})V_{k+1}^{+}(\\tilde{x}) \\tilde{m}$</td>\n</tr>\n<tr>\n<td>$u_{1} : C$</td>\n<td>$\\tilde{x} = \\mathbf{fv}(V)$</td>\n</tr>\n<tr>\n<td>$\\tilde{m} = (u_{1}, \\ldots, u_{i}+</td>\n<td>G(C)</td>\n</tr>\n<tr>\n<td>$(\\nu s : C)P'$</td>\n<td>$(\\nu \\tilde{s} : G(C))B_{k}^{+}(P')$</td>\n</tr>\n<tr>\n<td>$\\tilde{x} = \\mathbf{fv}(P')$</td>\n<td>$\\tilde{s} = (s_{1}, \\ldots, s_{</td>\n</tr>\n<tr>\n<td>$\\sigma = {s_{1}m_{1}/s_{1}}$ if $C = S$</td>\n<td>${s_{1}/s}$ if $C = \\langle U \\rangle$</td>\n</tr>\n<tr>\n<td>$Q \\cdot R$</td>\n<td>$c_{k}(\\tilde{x})c_{k+1}(\\tilde{y})B_{k+1}^{+}(\\tilde{x} \\cdot \\tilde{y})</td>\n</tr>\n<tr>\n<td>$\\tilde{y} = \\mathbf{fv}(Q)$</td>\n<td>$\\tilde{z} = \\mathbf{fv}(R)$</td>\n</tr>\n<tr>\n<td>$l =</td>\n<td>Q</td>\n</tr>\n<tr>\n<td>$\\lambda u : C^{\\rightarrow} P$</td>\n<td>$\\lambda \\tilde{y} : G(C)^{\\rightarrow} ((\\nu \\tilde{c})B_{k}^{+}(P[\\tilde{y}/y]))$</td>\n</tr>\n<tr>\n<td>$\\tilde{c} = {\\epsilon }$ if $\\sim \\rightarrow$</td>\n<td>$\\tilde{c} = (c_{k,1}, \\ldots, c_{k+</td>\n</tr>\n<tr>\n<td>$\\tilde{y} = \\mathbf{fv}(V)$</td>\n<td>$\\tilde{y} = (y_{1}, \\ldots, y_{</td>\n</tr>\n</tbody>\n</table>\n\n| Table 1 | The breakdown function for processes and values (core fragment). |\nProof. Direct from the definitions, using Thm. 3.10. See Appendix A.3 for details.\n\nRemarkably, \\( \\nu \\) will reduce in three steps to a process \\( \\nu \\). After this application, \\( c_3 \\) and \\( c_15 \\) can synchronize with their duals, and we know that \\( \\nu \\) is standing by to mimic the encoded exchange of value true. Indeed, the decomposition of the four-step reduced process in (2) will reduce in three steps to a process that is equal (up to \\( \\equiv \\)) to the process we obtained here. This strongly suggests a tight operational correspondence between a process and its decomposition.\n\nWe may now state our technical results:\n\n**Theorem 3.10 (Typability of Breakdown).** Let \\( P \\) be an initialized process and \\( V \\) be a value.\n\n1. If \\( \\Gamma; \\Lambda; \\Delta \\vdash P \\triangleright \\circ \\) then\n\n \\[ \\mathcal{G}(\\Gamma_1); \\emptyset; \\mathcal{G}(\\Delta) \\triangleright B_{\\mathcal{E}}^2(P) \\triangleright \\circ \\quad (k > 0) \\]\n\n where: \\( \\tilde{x} = fv(P) \\); \\( \\Gamma_1 = \\Gamma \\setminus \\tilde{x} \\); and balanced(\\( \\Theta \\)) with \\( \\text{dom}(\\Theta) = \\{c_k, c_{k+1}, \\ldots, c_{k+|V|−1}\\} \\cup \\{c_{k+1}, \\ldots, c_{k+|V|−1}\\} \\) and \\( \\Theta(c_k) = ?(\\tilde{M}) \\); end, where \\( \\tilde{M} = (\\mathcal{G}(\\Gamma), \\mathcal{G}(\\Delta))(\\tilde{x}) \\).\n\n2. If \\( \\Gamma; \\Lambda; \\Delta \\vdash V \\triangleright C \\rightarrow \\circ \\) then\n\n \\[ \\mathcal{G}(\\Gamma); \\mathcal{G}(\\Lambda); \\Theta \\triangleright V_\\mathcal{E}^6(V) \\triangleright \\mathcal{G}(C) \\rightarrow \\circ \\quad (k > 0) \\]\n\n where: \\( \\tilde{x} = fv(V) \\); and balanced(\\( \\Theta \\)) with \\( \\text{dom}(\\Theta) = \\{c_k, \\ldots, c_{k+|V|−1}\\} \\cup \\{c_k, \\ldots, c_{k+|V|−1}\\} \\) and \\( \\Theta(c_k) = ?(\\tilde{M}) \\); end, where \\( \\tilde{M} = (\\mathcal{G}(\\Gamma), \\mathcal{G}(\\Delta))(\\tilde{x}) \\).\n\n3. If \\( \\Gamma; \\emptyset; \\emptyset \\vdash V \\triangleright C \\rightarrow \\circ \\) then \\( \\mathcal{G}(\\Gamma); \\emptyset; \\emptyset \\triangleright V_\\mathcal{E}^6(V) \\triangleright \\mathcal{G}(C) \\rightarrow \\circ \\), where \\( \\tilde{x} = fv(V) \\) and \\( k > 0 \\).\n\n**Proof.** By mutual induction on the structure of \\( P \\) and \\( V \\). See Appendix A.2 for details.\n\nUsing the above theorem, we can prove our main result:\n\n**Theorem 3.11 (Typability of the Decomposition).** Let \\( P \\) be a closed HO process with \\( \\tilde{u} = fn(P) \\). If \\( \\Gamma; \\emptyset; \\emptyset \\vdash P \\triangleright \\circ \\) then \\( \\mathcal{G}(\\Gamma \\sigma); \\emptyset; \\mathcal{G}(\\Delta \\sigma) \\vdash \\mathcal{D}(P) \\triangleright \\circ \\), where \\( \\sigma = \\{\\text{init}(\\tilde{u})/\\tilde{u}\\} \\).\n\n**Proof.** Direct from the definitions, using Thm. 3.10. See Appendix A.3 for details.\n3.3 Extensions (I): Select and Branching\n\nWe now show how to extend the decomposition to handle select and branch processes, which implement labeled (deterministic) choice in session protocols, as well as their corresponding session types. As we will see, in formalizing this extension we shall appeal to the expressive power of abstraction-passing. We start by extending the syntax of minimal session types:\n\n**Definition 3.12 (Minimal Session Types (with Labeled Choice)).** The syntax of minimal session types for HO is defined as follows:\n\n\\[ M ::= \\text{end} \\mid !(\\tilde{U}); \\text{end} \\mid ?(\\tilde{U}); \\text{end} \\mid \\oplus\\{l_i : M_i\\}_{i \\in I} \\mid \\&\\{l_i : M_i\\}_{i \\in I} \\]\n\nwhere \\( U \\) and \\( C \\) are defined as in Def. 3.1.\n\nWe may then extend Def. 3.2 to branch and select types as follows:\n\n**Definition 3.13 (Decomposing Session Types, Extended (I)).** The decomposition function on types as given in Def. 3.2 is extended as follows:\n\n\\[\n\\begin{align*}\nG(\\&\\{l_i : S_i\\}_{i \\in I}) &= \\&\\{l_i : (S_i \\rightarrow \\circ \\circ) ; \\text{end}\\}_{i \\in I} \\\\\nG(\\oplus\\{l_i : S_i\\}_{i \\in I}) &= \\oplus\\{l_i : (S_i \\rightarrow \\circ) ; \\text{end}\\}_{i \\in I}\n\\end{align*}\n\\]\n\nThe above definition for decomposed types already suggests our strategy to breakdown branching and selection processes: we will exploit abstraction-passing to exchange one abstraction per each branch of the labeled choice. This intuition will become clearer shortly.\n\nWe now extend the definition of the degree of a process/value (cf. Def. 3.5) to account for branch and select processes:\n\n**Definition 3.14 (Degree of a Process, Extended).** The degree of a process \\( P \\), denoted \\( |P| \\), is as given in Def. 3.5, extended as follows:\n\n\\[\n|P| = \\begin{cases} \n1 & \\text{if } P = u_i \\triangleright \\{l_j : P_j\\}_{j \\in I} \\\\\n|P'| + 2 & \\text{if } P = u_i \\triangleleft l_j . P'\n\\end{cases}\n\\]\n\nThe definition of process decomposition (cf. Def. 3.8) does not require modifications; it relies on the extended definition of the breakdown function for processes \\( B_{\\tilde{x}}^k(\\cdot) \\) that combines the definitions in Tab. 1 with those in Tab. 3 (see below). The breakdown of values \\( V_{\\tilde{x}}^k(\\cdot) \\) is as before, and relies on the extended definition of \\( B_{\\tilde{x}}^k(\\cdot) \\).\n\nWe now present and describe the breakdown of branching and selection processes:\n\n**Branching** The breakdown of a branching process \\( u_i \\triangleright \\{l_j : P_j\\}_{j \\in I} \\) is as follows:\n\n\\[\nB_{\\tilde{x}}^k(u_i \\triangleright \\{l_j : P_j\\}_{j \\in I}) = c_k(\\tilde{x}).u_i \\triangleright \\{l_j : u_i!((N_{u,j})_{j \\in I})\\}_{j \\in I}\n\\]\n\nwhere \\( N_{u,j} = \\lambda \\tilde{y}^u_j : G(S_j).((\\nu \\tilde{c}_j)(\\tilde{r}_{k+1}(\\tilde{x})) | B_{\\tilde{x}}^{k+1}(P_j\\{y^u_j/u_i\\})) \\)\n\nThe first prefix receives the context \\( \\tilde{x} \\). The next two prefixes are along \\( u_i \\): the first one mimics the branching action of \\( P \\), whereas the second outputs an abstraction \\( N_{u,j} \\). This output does not have a counterpart in \\( P \\); it is meant to synchronize with an input in the breakdown of the corresponding selection process (see below). \\( N_{u,j} \\) encapsulates the breakdown of subprocess \\( P_j \\). It has the same structure as the breakdown of a value \\( \\lambda y : C^\\rightarrow P \\) in Tab. 1: it is a composition of a control trio and the breakdown of \\( P_j \\); the generated propagators, denoted \\( \\tilde{c}_j \\), are restricted. We use types to define \\( N_{u,j} \\): we assume \\( S_j \\) is the session type of \\( u_i \\) in the \\( j \\)-th branch of \\( P \\). We abstract over \\( \\tilde{y}^u_j \\) = \\( (y^u_j, \\ldots, y^u_j)_{j \\leq \\sigma(S_j)} \\). We substitute \\( u_i \\) with \\( y^u_i \\) in \\( P_j \\) before breaking it down: this way, \\( u_i \\) is decomposed and bound by abstraction.\nWe will investigate the decomposition of The composition Def. 3.14, we have: implementing subtraction. A client V\nan abstraction allows clients to add or subtract two integers. The server contains two branches: one sends\nof selection and branching processes by considering a basic mathematical server ▶ branch (see Appendix B for details).\n▶ Selection. The breakdown of a selection process \\( u_i \\triangleright l_j \\cdot P' \\) is as follows:\n\n\\[\n\\mathcal{B}_k^u(u_i \\triangleright l_j \\cdot P') = c_k(\\tilde{x}), x_{k+1}^{\\triangleright} (M_j) \\mid \\langle \\nu \\tilde{u} : \\mathcal{G}(S_j) \\rangle (c_{k+1}^{\\triangleright} (y). y \\tilde{\\nu} \\mid P'_{u_i+1/u_i})\n\\]\n\nwhere \\( M_j = \\lambda \\tilde{y}, u_i \\triangleright l_j, u_i ?(z). r_{k+2}^{\\triangleright} (\\tilde{x}). z \\tilde{y} \\)\n\nAfter receiving the context \\( \\tilde{x} \\), the abstraction \\( M_j \\) is sent along \\( r_{k+1}^{\\triangleright} \\), and is to be received by the second subprocess in the composition. This sequence of actions allows us to preserve the intended trio structure. We use \\( S_j \\), the type of \\( u_i \\) in \\( P' \\), to construct a corresponding tuple \\( \\tilde{u} \\), with type \\( \\mathcal{G}(S_j) \\). We apply the abstraction \\( M_j \\), received along \\( c_{k+1}^{\\triangleright} \\), to \\( \\tilde{u} \\) (the duals of \\( u_i \\)). At this point, the selection action in \\( P \\) can be mimicked, and so label \\( l_j \\) is chosen from the breakdown of a corresponding branching process. As discussed above, such a breakdown will send an abstraction \\( N_{u,j} \\) with type \\( S_j \\to \\circ \\), which encapsulates the breakdown of the chosen subprocess. Before running \\( N_{u,j} \\) with names \\( \\tilde{u} \\), we trigger the breakdown of \\( P' \\) with an appropriate substitution.\n\nSumming up, our strategy for breaking down labeled choices exploits higher-order concurrency to uniformly handle the fact that the subprocesses of a branching process have a different session type and degree. Interestingly, it follows the intuition that branching and selection correspond to a form of output and input actions involving labels, respectively.\n\n\\begin{itemize}\n\\item \\textbf{Remark 3.15.} Theorems 3.10 and 3.11 hold also for the extension with selection and branching (see Appendix B for details).\n\\item \\textbf{Example 3.16 (Breaking down Selection and Branching).} We illustrate the breaking down of selection and branching processes by considering a basic mathematical server \\( Q \\) that allows clients to add or subtract two integers. The server contains two branches: one sends an abstraction \\( V_+ \\) that implements integer addition, the other sends an abstraction \\( V_- \\) implementing subtraction. A client \\( R \\) selects the first option to add integers 16 and 26:\n\\[\nQ \\triangleq u \\triangleright \\{ \\text{add} : u! \\langle V_+ \\rangle .0, \\text{sub} : u! \\langle V_- \\rangle .0 \\}\n\\]\n\\[\nR \\triangleq \\tilde{u} \\triangleq \\text{add.} \\tilde{u}! \\langle x \\rangle .x \\quad (16,26)\n\\]\n\nThe composition \\( P \\triangleq (\\nu u)(Q \\mid R) \\) reduces in two steps to a process \\( V_+ \\):(16,26):\n\\[\nP \\quad \\longrightarrow \\quad (\\nu u)(u! \\langle V_+ \\rangle .0 \\mid \\tilde{u}! \\langle x \\rangle .x \\quad (16,26)) \\quad \\longrightarrow \\quad V_+ \\quad (16,26) \\quad (3)\n\\]\n\nWe will investigate the decomposition of \\( P \\), and its reduction chain. First, by Def. 3.5 and Def. 3.14, we have: \\( |Q| = 1 \\), \\( |R| = 4 \\), and \\( |P| = 6 \\). Following the extension of Def. 3.8, using\n\n\\begin{table}[h]\n\\centering\n\\begin{tabular}{|l|l|}\n\\hline\n\\( \\mathcal{B}_k^u \\) & \\( \\{ l_j : P_j \\} \\mid I \\) \\\\\n\\hline\n\\hline\n\\( c_k(\\tilde{x}), u_i \\triangleright \\{ l_j : u_i! \\langle N_{u,j} \\rangle \\} \\) & \\( y_i \\triangleright \\{ y_i^{\\triangleright} \\} \\) \\mid \\( \\mathcal{B}_k^{u_i}(P_j) \\) \\mid \\( y_i \\)\n\\hline\n\\hline\n\n\\end{tabular}\n\\caption{Table 3 The breakdown function for processes (extension with selection and branching).}\n\\end{table}\n11:16 Minimal Session Types\n\nk = 1, and observing that σ₁ = ∅, we obtain:\n\n\\[ D(P) = (ν v₁ \\ldots vₖ)(\\overline{τ}!().0 \\mid (ν u₁)(c₁?().c₂!().c₃!().0 \\mid B²(\\sigma) \\mid B²(\\langle \\sigma \\rangle))) \\]\n\nwhere σ₂ = \\{u₁u₂/u₃\\}. The breakdown of Q is obtained by applying the first rule in Tab. 3:\n\n\\[ B²(\\sigma) = c₁?().u₁ \\triangleright (\\text{add} : (ν v₁v₂)u₁!(\\lambda y₁.\\overline{τ}!().0 \\mid B²(\\sigma)(V₁).0{y₁/u₁}).0, \\]\n\nsub : (ν v₁v₂)u₁!(\\lambda y₁.\\overline{τ}!().0 \\mid B²(\\sigma)(V₁).0{y₁/u₁}).0 \\}\n\nThe breakdown of R is obtained by applying the second rule in Tab. 3:\n\n\\[ B²(\\sigma) = c₁?()c₂!().c₁?().c₂!().c₃!().0 \\]\n\n\\[ \\triangleright \\text{add} : (ν v₁v₂)u₁!(\\lambda y₂.\\overline{τ}!().z y₁).0 \\]\n\n\\[ \\mid (ν u₂)(c₁?()y₂{u₂/\\overline{τ}}) \\mid B²(\\overline{τ}?().z x (16,26)) \\}\n\nWe will now follow the chain of reductions of the process D(P). First, c₁, c₂, and c₃ will synchronize, after which c₄ will pass the abstraction. Let D(P) \\(\\rightarrow^4 P'\\), then we know:\n\n\\[ P' = (ν c₅c₆)(ν u₁)(u₁ \\triangleright (\\text{add} : (ν v₁v₂)u₁!(\\lambda y₁.\\overline{τ}!().0 \\mid B²(\\sigma)(V₁).0).0, \\]\n\nsub : (ν v₁v₂)u₁!(\\lambda y₁.\\overline{τ}!().0 \\mid B²(\\sigma)(V₁).0).0 \\}\n\n\\[ \\mid (ν u₂)(c₁?()y₂{u₂/\\overline{τ}}) \\mid B²(\\overline{τ}?().z x (16,26)) \\}\n\nIn \\(P', \\overline{u}_₇\\) will be applied to the abstraction with variable y₁. After that, the choice for the process labeled by \\text{add} is made. Process \\(P'\\) will reduce further as \\(P' \\rightarrow^2 P'' \\rightarrow^2 P'''\\), where:\n\n\\[ P'' = (ν c₅c₆)(ν u₁)((ν c₃c₄)u₁!(\\lambda y₁.\\overline{τ}!().0 \\mid B²(\\sigma)(V₁).0).0 \\]\n\n\\[ \\mid (ν u₂)(\\overline{τ}?().z y₂{u₂/\\overline{τ}}) \\mid B²(u₂?().z x (16,26)) \\]\n\n\\[ P''' = (ν c₃c₄c₅c₆)((ν u₂\\overline{τ}!().z y₂{u₂/\\overline{τ}}) \\mid B²(u₂?().z x (16,26)) \\]\n\nInterestingly, \\(P''\\) strongly resembles a decomposition of the one-step reduced process in (3). This advocates the operational correspondence between a process and its decomposition. <\n\n3.4 Extensions (II): Recursion\n\nWe extend the decomposition to handle HO processes in which names can be typed with recursive session types \\(\\mu\\)S. We consider recursive types which are \\textit{simple} and \\textit{contractive}, i.e., in \\(\\mu\\)S, the body \\(S \\neq t\\) does not contain recursive types. Unless stated otherwise, we shall handle \\textit{tail-recursive} session types such as \\(e.g., S = \\mu t.?!(\\text{Int}); ?!(\\text{Bool}); !!(\\text{Bool}); t\\). Non-tail-recursive session types such as \\(\\mu t.?((\\overline{t}, t) \\rightarrow \\varnothing); \\text{end}, \\) which is essential in the fully abstract encoding of HO\\(\\alpha\\) into HO [19], can also be accommodated; see Rem. 3.29 below.\n\nWe start by extending minimal session types (Def. 3.1) with minimal recursive types:\n\n\\textbf{Definition 3.17 (Minimal Recursive Session Types).} The syntax of minimal recursive session types for HO is defined as follows:\n\n\\[ M ::= \\gamma \\mid !(\\overline{U}); \\gamma \\mid ?!(\\overline{U}); \\gamma \\mid \\mu t. M \\]\n\n\\[ \\gamma ::= \\text{end} \\mid t \\]\n\nThus, types such as \\(\\mu t.?!(U); t\\) and \\(\\mu t.?!(U); t\\) are minimal recursive session types: in fact they are tail-recursive session types with exactly one session prefix. We extend Def. 3.2 as follows:\nWe shall also use the function \\( \\text{type} \\) given in Def. 3.2 is extended as:\n\n\\[\n\\begin{align*}\n\\text{type}(t) &= t \\\\\n\\text{type}(\\mu \\text{S}) &= \\begin{cases} \n\\text{R}(\\text{S}) & \\text{if } \\mu \\text{S is tail-recursive} \\\\\n\\mu \\text{type}(\\text{S}) & \\text{otherwise}\n\\end{cases}\n\\end{align*}\n\\]\n\nThere are several issues with this breakdown. One of them is typability: we have that \\( \\text{type}(\\text{S}) \\) is used exactly by one trio to perform exactly one action; the session associated to \\( u \\) ends after its single use, as prescribed by its minimal session type. The situation is different when names can have recursive types, for the names \\( u \\). Further, \\( \\text{type} \\) is decomposed using \\( \\text{R}(\\text{S}) \\) is tail-recursive, \\( \\text{R}(\\text{S}) \\) decomposes \\( \\text{R}(\\text{S}) \\) recursively obtained as follows: first, \\( \\text{R}(\\text{S}) \\) is the list of minimal recursive session types: it skips session prefixes until a type of form \\( \\mu \\text{S} \\) is encountered; when that occurs, the recursive type is decomposed using \\( \\text{R}(\\text{S}) \\). We illustrate Def. 3.18 with two examples:\n\n\\textbf{Example 3.19 (Decomposing a Recursive Type).} Let \\( \\text{S} = \\mu \\text{S'} \\) be a recursive session type, with \\( \\text{S'} = ?\\text{I}; ?\\text{B}; ?\\text{B}; t \\). By Def. 3.18, since \\( \\text{S} \\) is tail-recursive, \\( \\text{type}(\\text{S}) = \\text{R}(\\text{S'}) \\). Further, \\( \\text{R}(\\text{S'}) = \\mu \\text{type}(\\text{S}) \\), we obtain \\( \\text{type}(\\text{S}) = \\mu \\text{type}(\\text{S}) \\). Since \\( \\text{R}(t) = \\epsilon \\), we obtain \\( \\text{type}(\\text{S}) = \\mu \\text{type}(\\text{S}) \\).\\( \\triangleright \\)\n\n\\textbf{Example 3.20 (Decomposing an Unfolded Recursive Type).} Let \\( T = ?\\text{B}; !\\text{B}; \\text{S} \\) be a derived unfolding of \\( \\text{S} \\) from Exam. 3.19. Then, by Def. 3.18, \\( \\text{R}(\\text{S}) \\) is the list of minimal recursive types obtained as follows: first, \\( \\text{R}(\\text{S}) = \\text{R}(\\text{S}) \\). Finally, we have \\( \\text{R}(\\mu \\text{S}) = \\text{R}(\\text{S}) \\). We get the same list of minimal types as in Exam. 3.19: \\( \\text{R}(\\text{S}) = \\mu \\text{type}(\\text{S}) \\).\\( \\triangleleft \\)\n\nWe now explain how to decompose processes whose names are typed with recursive types. In the core fragment, we decompose a name \\( u \\) into a sequence of names \\( \\tilde{u} = (u_1, \\ldots, u_n) \\); each \\( u_i \\) is used exactly by one trio to perform exactly one action; the session associated to \\( u_i \\) ends after its single use, as prescribed by its minimal session type. The situation is different when names can have recursive types, for the names \\( \\tilde{u} \\) should be propagated in order to be used infinitely many times. As a simple example, consider the process\n\n\\[\nR = r?(x).r!(x).V \\ r\n\\]\n\nwhere name \\( r \\) has type \\( S = \\mu \\text{I} \\rightarrow \\text{I} \\rightarrow \\text{I} \\); t and the higher-order type of \\( V \\) is \\( S \\rightarrow \\epsilon \\). Processes of this form are key in the encoding of recursion given in [19]. A naive decomposition of \\( R \\), using the approach we defined for processes without recursive types, would result into\n\n\\[\n\\text{type}(R) = c_1?(\\cdot).r_1?(x).\\text{r}_2?(x).\\text{r}_3!(\\cdot).0 \\ | \\ c_2?(x).r_2!(x).\\text{r}_3!(\\cdot).0 \\ | \\ c_3?(\\cdot).V(x)(r_3, r_4)\n\\]\n\nThere are several issues with this breakdown. One of them is typability: we have that \\( r_1 : \\mu \\text{I} \\rightarrow \\text{I} \\); t, but subprocess \\( \\text{r}_2?(x).0 \\) is not typable under a linear environment containing such a judgment. Another, perhaps more central, issue concerns \\( r \\): the last trio (which mimics application) should apply to the sequence of names \\( (r_1, r_2) \\), rather than to \\( (r_3, r_4) \\). We address both issues by devising a mechanism that propagates names with recursive types (such as \\( (r_1, r_2) \\)) among the trios that use some of them. This entails decomposing \\( R \\) in\nsuch a way that the first two trios propagate $r_1$ and $r_2$ after they have used them; the trio\nsimulating $V r$ should then have a way to access the propagated names $(r_1, r_2)$.\n\nWe illustrate the key insights underpinning our solution by means of two examples. The\nfirst one illustrates how to break down input and output actions on names with recursive\ntypes (the “first part” of $R$). The second example shows how to break down an application\nwhere a value is applied to a tuple of names with recursive names (the “second part” of $R$).\n\n\\textbf{Example 3.21 (Decomposing Processes with Recursive Names (I)).} Let $P = r?(x).r!(x).P'$\nbe a process where $r$ has type $S = \\mu \\cdot (?)(\\text{Int}); !\\text{(!Int): t}$ and $r \\in \\text{fn}(P')$. To define $B^1_R(P)$ in\na compositional way, names $(r_1, r_2)$ should be provided to its first trio; they cannot be known\nbeforehand. To this end, we introduce a new control trio that will hold these names:\n\n$$c^r?(b).b(r_1, r_2)$$\n\nwhere the \\textit{shared} name $c^r$ provides a decomposition of the (recursive) name $r$. The intention\nis that each name with a recursive type $r$ will get its own dedicated propagator channel $c^r$.\n\nSince there is only one recursive name in $P$, its decomposition will be of the following form:\n\n$$D(P) = (\\nu c)(\\nu c^r)(c^r?(b).b(r_1, r_2) | \\tau!().0 | B^1_R(P))$$\n\nThe new control trio can be seen as a server that provides names: each trio that mimics some\naction on $r$ should request the sequence $\\tilde{r}$ from the server on $c^r$. This request will be realized\nby a higher-order communication: trios should send an abstraction to the server; such an\nabstraction will contain further actions of a trio and it will be applied to the sequence $\\tilde{r}$.\n\nFollowing this idea, we may refine the definition of $D(P)$ by expanding $B^1_R(P)$:\n\n$$D(P) = (\\nu c)(\\nu c^r)(c^r?(b).b(r_1, r_2) | \\tau!().0 | c_1?(().c^r!(N_1)).0 | c_2?(y).c^r!(N_2).0 | B^2_R(P))$$\n\nThe trios involving names with recursive types have now a different shape. After being\ntriggered by a previous trio, rather than immediately mimicking an action, they will send an\nabstraction to the server available on $c^r$. The abstractions $N_1$ and $N_2$ are defined as follows:\n\n$$N_1 = \\lambda (z_1, z_2). z_1?(x).\\tilde{t}_2!(x).c^r?(b).b(z_1, z_2) \\quad N_2 = \\lambda (z_1, z_2). z_2!(x).\\tilde{t}_3!(().c^r?(b).b(z_1, z_2)$$\n\nHence, the formal arguments for these values are meant to correspond to $\\tilde{r}$. The server on\nname $c^r$ will appropriately instantiate these names. Notice that all names in $\\tilde{r}$ are propagated,\neven if the abstractions only use some of them. For instance, $N_1$ only uses $r_1$, whereas $N_2$\nuses $r_2$. After simulating an action on $r_1$ and activating the next trio, these values reinstate\nthe server on $c^r$ for the benefit of future trios mimicking actions on $r$.\n\n\\textbf{Example 3.22 (Decomposing Processes with Recursive Names (II)).} Let $S = \\mu \\cdot (?)(\\text{Int}); !\\text{(!Int): t}$\nand $T = \\mu \\cdot (?)(\\text{Bool}); !\\text{(!Bool): t}$, and define $Q = V (u, v)$ as a process where $u : S$ and $v : T$,\nwhere $V$ is some value of type $(S, T) \\to \\phi$. The decomposition of $Q$ is as in the previous\nexample, except that now we need two servers, one for $u$ and one for $v$:\n\n$$D(Q) = (\\nu c \\tilde{e})(\\nu c^e)(e^u?(b).b(u_1, u_2) | e^v?(b).b(v_1, v_2) | \\tau!().0 | B^1_R(Q))$$\n\nwhere $\\tilde{e} = (c_2, \\ldots, c_{|Q|})$. We should break down $Q$ in such a way that it could communicate\nwith both servers to collect sequences $\\tilde{u}$ and $\\tilde{v}$. To this end, we define a process in which\nabstractions are nested using output prefixes and whose innermost process is an application.\nAfter successive communications with multiple servers this innermost application will have\ncollected all names in $\\tilde{u}$ and $\\tilde{v}$. We apply this idea to breakdown $Q$:\n\n$$B^1_R(Q) = c_1?(().e^u!(\\lambda (x_1, x_2). e^v!(\\lambda (y_1, y_2). V^2_R(V)(x_1, x_2, y_1, y_2)).0).0$$\nObserve that we use two nested outputs, one for each name with recursive types in $Q$. We now look at the reductions of $D(Q)$ to analyze how the communication of nested abstractions allows us to collect all name sequences needed. After the first reduction along $c_1$ we have:\n\n$$D(Q) \\rightarrow (\\nu \\tilde{c})(\\nu c^n c^a)(c^n?)(b) . b (u_1, u_2) \\mid c^n? (b) . b (v_1, v_2) \\mid c^n! (\\lambda(x_1, x_2). c^n! (\\lambda(y_1, y_2) . V^2_k (V) (x_1, x_2, y_1, y_2)) . 0) . 0 = R^1$$\n\nFrom $R^1$ we have a synchronization along name $c^n$:\n\n$$R^1 \\rightarrow (\\nu \\tilde{c})(\\nu c^n c^a)(\\lambda(x_1, x_2). c^n! (\\lambda(y_1, y_2) . V^2_k (V) (x_1, x_2, y_1, y_2)) . 0 (u_1, u_2) \\mid c^n? (b) . b (v_1, v_2)) = R^2$$\n\nUpon receiving the value, the server applies it to $(u_1, u_2)$ obtaining the following process:\n\n$$R^2 \\rightarrow (\\nu \\tilde{c})(\\nu c^n c^a)(\\lambda(y_1, y_2) . V^2_k (V) (u_1, u_2, y_1, y_2)) \\mid c^n? (b) . b (v_1, v_2)) = R^3$$\n\nNext, the first trio in $R^3$ can communicate with the server on name $c^n$:\n\n$$R^3 \\rightarrow (\\nu \\tilde{c})(\\nu c^n c^a)(\\lambda(y_1, y_2) . V^2_k (V) (u_1, u_2, y_1, y_2) (v_1, v_2))$$\n\nThis completes the instantiation of name variables with appropriate sequences of names with recursive types. At this point, $D(Q)$ can proceed to mimic the application in $Q$. \n\nThese two examples illustrate the main ideas of the decomposition of processes that involve names with recursive types. Tab. 4 presents a formal account of the extension of the definition of process decomposition given in Def. 3.8. Before explaining the table in detail, we require an auxiliary definition.\n\nGiven an unfolded recursive session type $S$, the auxiliary function $f(S)$ returns the position of the top-most prefix of $S$ within its body. (Whenever $S = \\mu t . S'$, we have $f(S) = 1$.)\n\n\\textbf{Definition 3.23 (Index function).} Let $S$ be an (unfolded) recursive session type. The function $f(S)$ is defined as follows:\n\n$$f(S) = \\begin{cases} f'_0(S' / t) & \\text{if } S = \\mu t . S' \\\\ f'_0(S) & \\text{otherwise} \\end{cases}$$\n\nwhere: $f'_0(\\mu t . S) = |R(S)| - l + 1$, $f'_0(\\langle \\rangle) = f'_0(\\langle \\rangle ; S) = f'_1(\\langle \\rangle ; S) = f'_1(\\langle \\rangle ; S) = f'_1(\\langle \\rangle ; S) = f'_1(\\langle \\rangle ; S)$.\n\n\\textbf{Example 3.24.} Let $S = \\langle \\langle \\rangle ; \\langle \\rangle ; \\langle \\rangle \\rangle$ where $S$ is as in Exam. 3.19. Then $f(S') = 2$ since the top-most prefix of $S'$ ($\\langle \\langle \\rangle ; \\langle \\rangle$) is the second prefix in the body of $S$. \n\nGiven a typed process $P$, we write $\\text{rn}(P)$ to denote the set of free names of $P$ whose types are recursive. As mentioned above, for each $r \\in \\text{rn}(P)$ with $r : S$ we shall rely on a control trio of the form $c^n? (b) . b \\tilde{r}$, where $\\tilde{r} = r_1, \\ldots, r_{|\\text{rn}(S)|}$.\n\n\\textbf{Definition 3.25 (Decomposition of a Process with Recursive Session Types).} Let $P$ be a closed HO process with $\\tilde{u} = \\text{fn}(P)$ and $\\tilde{v} = \\text{rn}(P)$. The decomposition of $P$, denoted $D(P)$, is defined as:\n\n$$D(P) = (\\nu \\tilde{c})(\\nu \\tilde{c}r)\\left( \\prod_{r \\in \\tilde{v}} c^n? (b) . b \\tilde{r} \\mid c^n! (\\langle \\rangle) . 0 \\mid B^k (P \\sigma) \\right)$$\n\nwhere: $k > 0$; $\\tilde{c} = (c_k, \\ldots, c_{k + |P| - 1})$; $\\tilde{c}r = \\bigcup_{r \\in \\tilde{v}} c^n$; $\\sigma = \\{ \\text{init} (\\tilde{u}) / \\tilde{u} \\}$. \n\nECOOP 2019\nWe now describe the required extensions for the function $B_k^S(r!(V),Q)$. All other prefixes can be treated as in Tab. 1.\n\n### Table 4: The breakdown function for processes and values (extension with recursive types).\n\n<table>\n<thead>\n<tr>\n<th>$B_k^S(r!(V),Q)$</th>\n<th>$c_k?((\\tilde{x}),c^i!(N_{V})) \\mid B_{k+1}^{k+i+1}(Q)$</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>where: $N_{V} = \\lambda \\tilde{z}.z_{f(S)}!(V_{y})\\cdot c^r?((b).(b \\tilde{z}))$</td>\n<td>$r : S \\land tr(S)$</td>\n</tr>\n<tr>\n<td>$y : fV(V)$. $\\tilde{w} : fV(Q)$</td>\n<td>$l =</td>\n</tr>\n<tr>\n<td>$\\tilde{z} = (z_1, \\ldots, z_{</td>\n<td>R \\cdot (S)</td>\n</tr>\n<tr>\n<td>$\\tilde{y} = (y_1, \\ldots, y_{</td>\n<td>R \\cdot (S)</td>\n</tr>\n<tr>\n<td>$\\tilde{c} = \\epsilon$ if $\\rightarrow \\rightarrow$</td>\n<td>$\\tilde{c} = \\left{ (c_k, \\ldots, c_{k+</td>\n</tr>\n</tbody>\n</table>\n\nWe now describe the required extensions for the function $B_k^S(\\cdot)$. We will use predicate $tr(S)$ on types to indicate that $S$ is a tail-recursive session type. Tab. 4 describes the breakdown of prefixes whose type is recursive; all other prefixes can be treated as in Tab. 1.\n\n**Output** The breakdown of process $r!(V),Q$, when $r$ has a recursive type $S$, is as follows:\n\n$$B_k^S(r!(V),Q) = c_k?((\\tilde{x}),c^i!(N_{V})) \\mid B_{k+1}^{k+i+1}(Q)$$\n\nwhere $N_{V} = \\lambda \\tilde{z}.z_{f(S)}!(V_{y})\\cdot c^r?((b).(b \\tilde{z}))$\n\nThe decomposition consists of a leading trio that mimics the output action running in parallel with the breakdown of $Q$. After receiving the context $\\tilde{x}$, the leading trio sends an abstraction $N_{V}$ along $c^r$. Value $N_{V}$ performs several tasks. First, it collects the sequence $\\tilde{r}$; then, it mimics the output action of $P$ along one of them $(r_{f(S)})$ and triggers the next trio, with context $\\tilde{w}$; finally, it reinstates the server on $c^r$ for the next trio that\nThe breakdown of process $r^!(y).Q$. For simplicity we consider applications $V(\\tilde{r}, u_i)$, where names in $\\tilde{r}$ have recursive types and only name $u_i$ has a non-recursive type; the general case involving different orders in names and multiple names with non-recursive types is as expected. We have:\n\n$$B^k_{\\tilde{r}}(V(\\tilde{r}, u_i)) = c_k ?(\\tilde{x}).c'^!(\\lambda z_1, c'^!(\\lambda z_2, \\cdots c'^!(\\lambda z_n, V^k_{\\tilde{r}}(\\tilde{z}_1, \\ldots, \\tilde{z}_n, \\bar{m}))))$$\n\nWe rely on types to decompose every name in $\\tilde{r}$, $u_i$. Letting $|\\tilde{r}| = n$ and $i \\in \\{1, \\ldots, n\\}$, for each $r_i \\in \\tilde{r}$ (with $r_i : S_i$) we generate a sequence $\\tilde{z}_i = (z_1^i, \\ldots, z^i_{|R_i(S_i)|})$ as in the output case. Since name $u_i$ has a non-recursive type, we decompose it as in Tab. 1. Subsequently, we define an output action on propagator $c^+$ that sends a value containing $n$ abstractions that occur nested within output prefixes: for each $j \\in \\{1, \\ldots, n-1\\}$, each abstraction binds $z_j$ and sends the next abstraction along $c^{j+1}$. The innermost abstraction abstracts over $\\tilde{z}_n$ and encapsulates process $V^k_{\\tilde{r}}(\\tilde{z}_1, \\ldots, \\tilde{z}_n, \\bar{m})$, which mimics the application in the source process. By this abstraction nesting we bind all variables $\\tilde{z}_i$ in $Q$. This structure can be seen as an encoding of partial application: by virtue of a single synchronization on $c^+$ part of variables (i.e., $\\tilde{z}_i$) will be instantiated.\n\nThe breakdown of a value application of the form $y(\\tilde{r}, u_i)$ results into a specific form of the breakdown:\n\n$$B^k_{\\tilde{r}}(y(\\tilde{r}, u_i)) = c_k ?(\\tilde{x}).c'^!(\\lambda z_1, c'^!(\\lambda z_2, \\cdots c'^!(\\lambda z_n, y(\\tilde{z}_1, \\ldots, \\tilde{z}_n, \\bar{m}))))$$\n\n**Rest** The restriction process $(\\nu s : \\mu t. S)P'$ is translated as follows:\n\n$$B^k_{\\tilde{r}}((\\nu s : \\mu t. S)P') = (\\nu \\bar{s} : R(S))(\\nu c^e) c^e? (b)(\\bar{s}) \\mid (\\nu c^e) c^e? (b)(\\bar{\\bar{s}}) \\mid B^k_{\\tilde{r}}(P')$$\n\nWe decompose $s$ into $\\bar{s} = (s_1, \\ldots, s_{|R(S)|})$ and $\\bar{\\bar{s}} = (\\bar{\\bar{s}}_1, \\ldots, \\bar{\\bar{s}}_{|R(S)|})$. The breakdown introduces two servers in parallel with the breakdown of $P'$; these servers provide names for $s$ and $\\bar{s}$ along $c^e$ and $c^\\pi$, respectively. The server on $c^e$ (resp. $c^\\pi$) receives a value and applies it to the sequence $\\bar{s}$ (resp. $\\bar{\\bar{s}}$). We restrict over $\\bar{s}$ and propagators $c^e$ and $c^\\pi$.\n\n**V** The polyadic value $\\lambda(y, z) : (\\tilde{S}, C)^\\rightarrow P$, where $\\neg \\epsilon \\in \\{-\\rightarrow, \\rightarrow\\}$, is decomposed as follows:\n\n$$V^k_{\\tilde{r}}(\\lambda(y, z) : (\\tilde{S}, C)^\\rightarrow P) = \\lambda(y^1, \\ldots, y^n, \\bar{z}) : (G(S_1), \\ldots, G(S_n), G(C))^{\\rightarrow \\rightarrow \\rightarrow \\rightarrow \\rightarrow \\rightarrow} \\mid N$$\n\nwhere: $N = (\\nu c) \\prod_{i \\in [y]} (c^e? (b)(b y^i)) \\mid \\tau e!(\\bar{\\pi}) \\mid B^k_{\\tilde{r}}(P^{z_1/z})$\n\nWe assume variables in $\\tilde{y}$ have recursive session types $\\tilde{S}$ and variable $z$ has some non-recursive session type $C$; the general case involving different orders in variables and\nmultiple variables with non-recursive types is as expected. Every variable \\( y_i \\) (with \\( y_i : S_i \\)) is decomposed into \\( \\tilde{y}^i = (y_1, \\ldots, y_{|S|}) \\). Variable \\( z \\) is decomposed as in Tab. 1. The breakdown is similar to the (monadic) shared value given in Tab. 1. In this case, for every \\( y_i \\in \\tilde{y}^i \\) there is a server \\( \\epsilon^y_i : (\\tilde{b} \\tilde{y}^i) \\) as a subprocess in the abstracted composition. The rationale for these servers is as described in previous cases.\n\nTo sum up, each trio using a name with a recursive session type first receives a sequence of names; then, it uses one of such names to mimic the appropriate action; finally, it propagates the entire sequence by reinstating a server defined as a control trio. Interestingly, this scheme for name propagation follows the implementation of the encoding of name-passing in HO.\n\n▶ **Example 3.26 (Breakdown of Recursion Encoding).** Consider the recursive process \\( P = \\mu X.a?(m).a!(\\nu s)(V(a, s) \\mid \\sigma(V).0) \\)\n\nwhere the value \\( V \\) is an abstraction that potentially reduces to \\( \\llbracket V \\rrbracket \\):\n\n\\[\nV = \\lambda(x_a, y_1) . y_1 ?(z_x) . x_a !(m) . x_a !(m) . (\\nu s)(z_x (x_a, s) \\mid \\sigma(V).0)\n\\]\n\nWe compose \\( \\llbracket P \\rrbracket \\) with an appropriate client process to illustrate the encoding of recursion:\n\n\\[\n\\llbracket P \\rrbracket = a!(W).a?(b).R\n\\]\n\n\\[\n\\xrightarrow{\\epsilon^a} (\\nu s)(V(a, s) \\mid \\sigma(V).0) \\mid R\n\\]\n\n\\[\n\\xrightarrow{(\\nu s)(\\nu s'):(z_x) . a?(m).a!(m).\\nu s)(z_x (a, s') \\mid \\sigma(V).0) \\mid \\sigma(V).0) \\mid R\n\\]\n\n\\[\n\\xrightarrow{a?(m).a!(m).\\nu s)(V(a, s') \\mid \\sigma(V).0) \\mid R = \\llbracket P \\rrbracket \\mid R\n\\]\n\nwhere \\( R \\) is some unspecified process such that \\( a \\in \\text{rn}(R) \\). We now analyze \\( D(\\llbracket P \\rrbracket) \\) and its reduction chain. By Def. 3.5, we have \\( \\llbracket P \\rrbracket = 7 \\), and \\( |V| = 0 \\). Then, we choose \\( k = 1 \\) and observe that \\( s = \\{a!; a?; \\epsilon^a\\} \\).\n\nFollowing Def. 3.25, we get:\n\n\\[\nD(\\llbracket P \\rrbracket) = (\\nu c_1, \\ldots, c_7)(\\nu c^a)(c^a?(b).b(a_1, a_2) \\mid \\sigma(\\nu s)(V).0 \\mid B^1_1(\\llbracket P \\rrbracket_\\sigma))\n\\]\n\n\\[\nB^1_1(\\llbracket P \\rrbracket_\\sigma) = c_1!(\\mu c^a!((\\lambda(z_1, z_2) . z_1 !(m).\\sigma(\\nu s)(V).0 \\mid c_2!(m).c^a!(\\lambda(z_1, z_2) . z_1 !(m).\\sigma(\\nu s)(V).0 \\mid c_3!(\\lambda(z_1, z_2).\\nu s)(V(z_1, z_2, s_1)).0\n\\]\n\n\\[\n| c_4!(\\nu s)(V(z_1, z_2)).\\sigma(\\nu s)(V(z_1, z_2)).0 \\mid \\epsilon(\\sigma(\\nu s)(V(z_1, z_2)).0)\n\\]\n\nThe decomposition relies twice on the breakdown of value \\( V \\), so we give \\( \\nu s^k(V) \\) here for arbitrary \\( k > 0 \\). For this, we observe that \\( V \\) is an abstraction of a process \\( Q \\) with \\(|Q| = 7 \\).\n\n\\[\n\\nu s^k(V) = \\lambda(x_{a_1}, x_{a_2}, y_1). (\\nu c_1, \\ldots, c_9, c_{k+6})(c^a?((b . x_{a_1}, x_{a_2}) \\mid \\sigma(\\nu s)^k(V)).0 \\mid B^k_1(Q))\n\\]\n\n\\[\nB^k_1(Q) = c_k!(\\nu y_1)(z_x).c^k!((\\lambda(z_1, z_2).z_1 !(m).\\sigma(\\nu s)(V(z_1, z_2)).0\n\\]\n\n\\[\n| c_{k+1}!(\\lambda(z_1, z_2) . z_1 !(m).\\sigma(\\nu s)(V(z_1, z_2)).0\n\\]\n\n\\[\n| c_{k+2}!(\\lambda(z_1, z_2) . z_2 !(m).\\sigma(\\nu s)(V(z_1, z_2)).0\n\\]\n\n\\[\n| (\\nu s_1)(c_1!(\\lambda(z_1, z_2).z_1 !(m).\\sigma(\\nu s)(V(z_1, z_2)).0\n\\]\n\n\\[\n| c_{k+3}!(\\lambda(z_1, z_2).z_1 !(m).\\sigma(\\nu s)(V(z_1, z_2)).0\n\\]\n\n\\[\n| (\\nu s_1)(c_1!(\\lambda(z_1, z_2).z_1 !(m).\\sigma(\\nu s)(V(z_1, z_2)).0\n\\]\n\nWe follow the reduction chain on \\( D(\\llbracket P \\rrbracket) \\) until it is ready to mimic the first action with channel \\( a \\), which is an input. First, \\( c_1 \\) will synchronize, after which \\( c^a \\) sends the abstraction\nto which then \\((a_1, a_2)\\) is applied. We obtain \\(D([P]) \\xrightarrow{3} (\\nu c_2, \\ldots, c_7, c_9)P'\\), where\n\n\\[\nP' = a_1?((m).\\overline{c_9}!((m).c_9?((b).b(a_1, a_2))\n| c_2?((m).c_9!((\\lambda(z_1, z_2).z_2!((m).\\overline{c_9}!()c_9?((b).b(z_1, z_2))).0)\n| (\\nu s_1)(c_3()c_9!().\\overline{c_9}!().0 | c_4()c_9!((\\lambda(z_1, z_2).V^{\\mu}_c(V)(z_1, z_2, s_1))).0\n| c_5()z_1!((\\mu^\\rho_c(V)).\\overline{c_9}!().0 | c_7?().0)\n\\]\n\nNote that this process is awaiting an input on channel \\(a_1\\), after which \\(c_2\\) can synchronize with its dual. At that point, \\(c_9\\) is ready to receive another abstraction that mimics an input on \\(a_1\\). This strongly suggests a tight operational correspondence between a process \\(P\\) and its decomposition in the case where \\(P\\) performs higher-order recursion.\n\nBelow we write \\(\\Delta_\\mu\\) to denote a session environment that concerns only recursive types. We state our main results:\n\n\\begin{theorem}[Typability of Breakdown] Let \\(P\\) be an initialized HO process and \\(V\\) be a value.\n\\begin{enumerate}\n\\item If \\(\\Gamma; \\Delta; \\Delta_\\mu \\vdash P \\triangleright \\omega\\) then \\(G(\\Gamma); G(\\Delta); \\Theta \\vdash B_k^k (P) \\triangleright \\omega\\) where: \\(\\overline{c} = \\text{dom}(\\Delta_\\mu)\\); \\(\\Phi = \\prod_{\\forall \\theta \\in c^\\prime} \\theta : (R^* (\\Delta_\\mu (r)) \\rightarrow \\circ)\\); \\(\\overline{d} = f v (P); k > 0; \\Gamma = \\Gamma \\setminus \\overline{d}\\); \\(\\Theta = \\text{balanced}(\\Theta)\\) with \\(\\text{dom}(\\Theta) = \\{c_k, \\ldots, c_{k+p-1}\\} \\cup \\{u_{k+1}, \\ldots, u_{k+p-1}\\}\\) such that \\(\\Theta(c_k) = ?(\\overline{M})\\) end, where \\(\\overline{M} = (G(\\Gamma), G(\\Lambda))(\\overline{d})\\).\n\\item If \\(\\Gamma; \\Delta \\vdash V \\triangleright C \\rightarrow \\omega\\) then \\(G(\\Gamma); G(\\Delta); \\Theta \\vdash V^{\\mu}_c(V) \\triangleright G(C) \\rightarrow \\omega\\), where: \\(\\overline{c} = f v (V); k > 0; \\text{balanced}(\\Theta)\\) with \\(\\text{dom}(\\Theta) = \\{c_k, \\ldots, c_{k+|V|-1}\\} \\cup \\{u_{k+1}, \\ldots, u_{k+|V|-1}\\}\\) such that \\(\\Theta(c_k) = ?(\\overline{M})\\) end, where \\(\\overline{M} = (G(\\Gamma), G(\\Lambda))(\\overline{d})\\).\n\\item If \\(\\Gamma; \\emptyset \\vdash V \\triangleright C \\rightarrow \\omega\\) then \\(G(\\Gamma); \\emptyset; \\emptyset \\vdash V^{\\mu}_c(V) \\triangleright G(C) \\rightarrow \\omega\\) where \\(\\overline{c} = f v (V)\\) and \\(k > 0\\).\n\\end{enumerate}\n\\end{theorem}\n\n\\begin{proof}\nBy mutual induction on the structure of \\(P\\) and \\(V\\). See Appendix C.1 for details.\n\\end{proof}\n\n\\begin{theorem}[Typability of the Decomposition with Recursive Types] Let \\(P\\) be a closed HO process with \\(\\overline{u} = \\text{fn}(P)\\) and \\(\\overline{v} = \\text{rn}(P)\\). If \\(\\Gamma; \\emptyset; \\Delta; \\Delta_\\mu \\vdash P \\triangleright \\omega\\), where \\(\\Delta_\\mu\\) only involves recursive session types, then \\(G(\\Gamma); \\emptyset; G(\\Delta); G(\\Delta_\\mu) \\vdash D(P) \\triangleright \\omega\\), where \\(\\sigma = \\{\\text{init}(\\overline{u})/\\overline{v}\\}\\).\n\\end{theorem}\n\n\\begin{proof}\nDirectly from the definitions, using Thm. 3.27. See Appendix C.2 for details.\n\\end{proof}\n\n\\begin{remark}[Non-Tail-Recursive Session Types] Our definitions and results apply to tail-recursive session types. We can accommodate the non-tail-recursive type \\(\\mu t.((\\overline{T}, t) \\rightarrow \\omega)\\) end into our approach: in Def. 3.18, we need to have \\(G(\\mu t.S) = \\mu t. G(S)\\) if \\(\\mu t.S\\) is non-tail-recursive. The decomposition functions for non-recursive session types suffice in this case.\n\\end{remark}\n\n## 4 Optimizations of the Decomposition\n\nHere we briefly discuss two optimizations of the decompositions. They simplify the structure of trios and the underlying communication discipline. Interestingly, they are both enabled by the higher-order nature of HO. In fact, they hinge on thunk processes, i.e., inactive processes that can be activated upon reception. We write \\([[P]]\\) to stand for the thunk process \\(\\lambda x : (\\text{end} \\rightarrow \\omega). P,\\) with \\(x \\not\\in \\text{fn}(P)\\). We write \\(\\text{run} [[P]]\\) to denote the application of a thunk to a (dummy) name of type \\text{end} \\rightarrow \\omega.\\) This way, we have \\(\\text{run} [[P]] \\rightarrow P.\\)\n11:24 Minimal Session Types\n\nFrom Trios to Duos We can simplify the breakdown functions by replacing trios with duos, i.e., processes with exactly two sequential prefixes. The idea is to transform trios such as $c_k?\\langle x \\rangle.\\text{run}b(V).c_{k+1}!(\\langle \\tilde{y} \\rangle)$ into the composition of a duo with a control trio:\n\n$$c_k?\\langle x \\rangle.c_{k+1}!(\\langle u!V.\\langle \\tilde{z} \\rangle \\langle \\tilde{y} \\rangle \\rangle) \\mid c_{k+1}?(b).\\text{run}b$$ \\hspace{1cm} (4)\n\nThe first action is as before; the two remaining prefixes are encapsulated into a thunk. This thunk is sent via a propagator to the control trio that activates it upon reception. This transformation involves an additional propagator, denoted $c_{k+2}$ above. This requires minor modifications in the definition of the degree function $\\cdot | \\cdot$ (cf. Def. 3.5).\n\nIn some cases, the breakdown function in §3.2 already produces duos. Breaking down input and output prefixes and parallel composition involves proper trios; following the scheme illustrated by (4), we can define a map $[\\cdot | \\cdot]$ to transform these trios into duos:\n\n$$\\begin{align*}\n&\\langle c_k?\\langle x \\rangle.\\text{run}b(V).c_{k+1}!(\\langle \\tilde{z} \\rangle) \\rangle \\mid c_{k+1}?(b).\\text{run}b \\\\\n&\\langle c_k?\\langle x \\rangle.\\text{run}b(y).c_{k+1}!(\\langle \\tilde{z} \\rangle) \\rangle \\mid c_{k+1}?(b).\\text{run}b \\\\\n&\\langle c_k?\\langle x \\rangle.\\text{run}b(\\langle \\tilde{y} \\rangle).c_{k+1}!(\\langle \\tilde{z} \\rangle) \\rangle \\mid c_{k+1}?(b).\\text{run}b\n\\end{align*}$$\n\nIn the breakdown given in §3.3 there is a proper trio, which can be transformed as follows:\n\n$$\\langle u_i \\triangleleft_{l_j} u_i?(z).\\text{run}b(\\langle \\tilde{x} \\rangle.\\langle \\tilde{y} \\rangle) \\rangle = u_i \\triangleleft_{l_j} \\text{run}b(\\langle u_i?(z).\\langle \\tilde{x} \\rangle.\\langle \\tilde{y} \\rangle \\rangle) \\mid c_{k+1}(b).\\text{run}b$$\n\nSimilarly, in the breakdown function extended with recursion (cf. §3.4) there is only one trio pattern, which can be transformed into a duo following the very same idea.\n\nFrom Polyadic to Monadic Communication Since we consider closed HO processes, we can dispense with polyadic communication in the breakdown function. We can define a monadic decomposition, $D(P)$, that simplifies Def. 3.8 as follows:\n\n$$D(P) = (\\nu z)(c_k?b).\\text{run}b \\mid B^k(P\\sigma)$$\n\nwhere $k > 0$, $\\tilde{c} = (c_k, \\ldots, c_{k+|P|-1})$, and $\\sigma$ is as in Def. 3.8. Process $c_k?b.\\text{run}b$ activates a thunk received from $B^k(\\cdot)$, the monadic breakdown function that simplifies the one in Tab. 1 by using only one parameter, namely $k$:\n\n$$\\begin{align*}\nB^k(u_i?(x).Q) &= (\\nu \\tilde{c}_x)(\\text{run}b(\\langle \\tilde{v} \\rangle(\\langle u_i?x.\\tilde{c}_x.b.\\text{run}b(x) \\rangle) \\mid B^{k+1}(Q\\sigma)) \\\\\nB^k(u_i!(x).Q) &= \\text{run}b(\\langle \\tilde{c}_x!(\\langle c_x?x.\\text{run}b(x) \\rangle \\rangle \\mid B^{k+1}(Q\\sigma) \\\\\nB^k(u_i!(V).Q) &= \\text{run}b(\\langle \\tilde{v} \\rangle(\\langle u_i!(V^k+1(V\\sigma)) \\rangle \\rangle \\mid B^{k+1}(Q\\sigma) \\\\\nB^k(x u) &= \\text{run}b(\\langle \\tilde{v} \\rangle(\\langle c_x?(x)\\tilde{u} \\rangle \\rangle) \\\\\nB^k(V u) &= \\text{run}b(\\langle \\tilde{v} \\rangle(\\langle V^k+1(V)\\tilde{u} \\rangle \\rangle) \\\\\nB^k((\\nu s)P') &= (\\nu \\tilde{c}_x)(\\text{run}b(P\\sigma) \\\\\nB^k(Q \\mid R) &= \\text{run}b(\\langle c_{k+1}?(b)\\text{run}b \\mid c_{k+1}(Q(b)\\text{run}b) \\rangle \\rangle \\mid B^{k+1}(Q) \\mid B^{k+1}(Q\\sigma) \\mid R\n\\end{align*}$$\n\nAbove, $\\sigma$ is as in Tab. 1. $B^k(\\cdot)$ propagates values using thunks and a dedicated propagator $c_x$ for each variable $x$. We describe only the definition of $B^k(u_i?(x).Q)$: it illustrates key ideas common to all other cases. It consists of an output of a thunk on $c_k$ composed in parallel with $B^{k+1}(Q\\sigma)$. The thunk will be activated by a process $c_k?b.\\text{run}b$ at the top-level; this activation triggers the input action on $u_i$, and prepares the activation for the next thunk (exchanged on name $c_{k+1}$). Upon reception, such a thunk is activated in\nparallel with $c_x!\\langle x \\rangle$, which propagates the value received on $u_i$. The scope of $c_x$ is restricted to include input actions on $c_x$ in $B^{k+1}\\{Q\\sigma\\}$; such actions are the first in the thunks present in, e.g., $B^k(u_i!\\langle x \\rangle.Q)$. We also need to revise the breakdown function for values $\\downarrow^S\\langle \\cdot \\rangle$. The breakdown functions given in §3.3 and §3.4 (cf. Tables 3 and 4) can be made monadic following similar lines.\n\nThese two optimizations can be combined by transforming the trios of the monadic breakdown into duos, following the key idea of the first optimization (cf. (4)).\n\n5 Related Work\n\nOur developments are related to results by Parrow [24], who showed that every process in the untyped, summation-free $\\pi$-calculus with replication is weakly bisimilar to its decomposition into trios processes (i.e., $P \\approx D(P)$). We draw inspiration from insights developed in [24], but pursuing different goals in a different technical setting: our decomposition treats processes from a calculus without name-passing but with higher-order concurrency (abstraction-passing), supports labeled choices, and accommodates recursive types. Our goals are different than those in [24] because trios processes are relevant to our work in that they allow us to formally justify minimal session types; however, they are not an end in themselves. Still, we opted to retain the definitional style and terminology for trios from [24], which are elegant and clear.\n\nOur main result connects the typability of a process with that of its decomposition; this is a static guarantee. Based on our examples, we conjecture that the behavioral guarantee given by $P \\approx D(P)$ in [24] holds in our setting too, under an appropriate typed weak bisimilarity. An obstacle here is that known notions of typed bisimilarity for session-typed processes, such as those given by Kouzapas et al. [20], are not adequate: they only relate processes typed under the same typing environments. We need a relaxed equivalence that (i) relates processes typable under different environments (e.g., $\\Delta$ and $G(\\Delta)$) and (ii) admits that actions along $s$ from $P$ can be matched by $D(P)$ using actions along $s_k$, for some $k$ (and vice versa). Defining this notion precisely and studying its properties goes beyond the scope of this paper.\n\nOur approach is broadly related to works that relate session types with other type systems for the $\\pi$-calculus (cf. [17, 3, 4, 5, 10]). Kobayashi [17] encoded a finite session $\\pi$-calculus into a $\\pi$-calculus with linear types with usages (without sequencing); this encoding uses a continuation-passing style to codify a session name using multiple linear channels. Dardha et al. [3, 4] formalize and extend Kobayashi’s approach. They use two separate encodings, one for processes and one for types. The former uses a freshly generated linear name to mimic each session action; this fresh name becomes an additional argument in communications. Polyadicity is thus an essential ingredient in [3, 4], whereas in our work it is convenient but not indispensable (cf. §4). The encoding of types in [3, 4] codifies sequencing in session types by nesting payload types. In contrast, we “slice” the $n$ actions occurring in a session $s$ along indexed names $s_1, \\ldots, s_n$ with minimal session types, i.e., slices of the type for $s$. All in all, an approach based on minimal session types appears simpler than that in [3, 4].\n\nWorks by Padovani [23] and Scalas et al. [25] is also related: they rely on [3, 4] to develop verification techniques based on session types for OCaml and Scala programs, respectively.\n\nGay et al. [10] formalize how to encode a monadic $\\pi$-calculus, equipped with a finite variant of the binary session types of [9], into a polyadic $\\pi$-calculus with an instance of the generic process types of [16]. The work of Demangeon and Honda [5] encodes a session $\\pi$-calculus into a linear/affine $\\pi$-calculus with subtyping based on choice and selection types. Our developments differ from these previous works in an important respect: we relate two formulations of session types, namely standard session types and minimal session types.\nIndeed, while [17, 3, 4, 5, 10] target the relative expressiveness of session-typed process languages, our work emerges as the first study of absolute expressiveness in this context.\n\nFinally, we elaborate further on our choice of HO as source language. HO is a sub-calculus of HOπ, whose basic theory and expressivity were studied by Kouzapas et al. [19, 20] as a hierarchy of session-typed calculi based on relative expressiveness. Our developments enable us to include HO with minimal session types within this hierarchy. Still, our approach does not rely on having HO as source language, and can be adapted to other typed frameworks based on session types, such as the type discipline for first-order π-calculus processes in [26].\n\n6 Concluding Remarks\n\nSession types are a class of behavioral types for message-passing programs. We presented a decomposition of session-typed processes in [19, 20] using minimal session types, in which there is no sequencing. The decomposition of a process \\( P \\), denoted \\( D(P) \\), is a collection of trios processes that trigger each other mimicking its sequencing. We prove that typability of \\( P \\) using standard session types implies the typability of \\( D(P) \\) with minimal session types. Our results hold for all session types constructs, including labeled choices and recursive types.\n\nOur contributions can be interpreted in three ways. First, from a foundational standpoint, our study of minimal session types is a conceptual contribution to the theory of behavioral types, in that we precisely identify sequencing as a source of redundancy in all preceding session types theories. As remarked in §1, there are many session types variants, and their expressivity often comes at the price of an involved underlying theory. Our work contributes in the opposite direction, as we identified a simple yet expressive fragment of an already minimal session-typed framework [19, 20], which allows us to justify session types in terms of themselves. Understanding further the underlying theory of minimal session types (e.g., notions such as type-based compatibility) is an exciting direction for future work.\n\nSecond, our work can be seen as a new twist on Parrow’s decomposition results in the untyped setting [24]. While Parrow’s work indeed does not consider types, in fairness we must observe that when Parrow’s work appeared (1996) the study of types for the π-calculus was rather incipient (for instance, binary session types appeared in 1998 [12]). That said, we should stress that our results are not merely an extension of Parrow’s with session types, for types in our setting drastically narrow down the range of conceivable decompositions. Also, we exploit features not supported in [24], most notably higher-order concurrency.\n\nLast but not least, from a practical standpoint, we believe that our approach paves a new avenue to the integration of session types in programming languages whose type systems lack sequencing, such as Go. It is natural to envision program analysis tools which, given a message-passing program that should conform to protocols specified as session types, exploit our decomposition as an intermediate step in the verification of communication correctness. Remarkably, our decomposition lends itself naturally to an implementation—in fact, we generated our examples automatically using MISTY, an associated artifact written in Haskell.\n\nReferences\n\n\nAppendix to §3.2\n\nA.1 Auxiliary Results\n\nRemark A.1. We derive polyadic rules for typing \\( \\text{HO}_\\pi \\) as an expected extension of \\( \\text{HO} \\) typing rules:\n\n\\[\n\\begin{align*}\n\\text{PolyVar} & : \\Gamma, \\bar{x} : \\bar{U}; \\\n\\text{PolySess} & : \\Gamma; \\emptyset; \\bar{u} : S \\vdash \\bar{u} \\triangleright S \\\\\n\\text{PolyRev} & : \\Gamma; \\Delta_1, \\Delta, u : S \\vdash P \\triangleright \\triangleright \\quad \\Gamma; \\emptyset; \\bar{x} \\triangleright \\bar{U} \\\\\n\\text{PolySend} & : \\Gamma; \\Delta_1, \\Delta, u : S \\vdash P \\triangleright \\triangleright \\quad \\Gamma; \\emptyset; \\bar{x} \\triangleright \\bar{U} \\\\\n\\text{PolyApp} & : \\Gamma; \\Delta_1, \\Delta, \\bar{x} : \\bar{C} \\vdash V \\triangleright \\sim \\circ \\quad \\Gamma; \\emptyset; \\Delta_2 \\vdash \\bar{u} \\triangleright \\bar{C} \\\\\n\\text{PolyAbs} & : \\Gamma; \\Delta_1, \\Delta, \\bar{x} : \\bar{a} ; \\bar{a} : U ; \\emptyset ; \\Delta \\vdash P \\\\\n\\text{PolyRes} & : \\Gamma; \\Delta, \\bar{s} : \\bar{s}_1, \\bar{s}_2 : \\bar{P} \\\\\n\\text{PolyResS} & : \\Gamma; \\Delta, \\bar{s}_1, \\bar{s}_2 : \\bar{P} \\\\\n\\end{align*}\n\\]\n\nLemma A.2 (Substitution Lemma [19]). \\( \\Gamma; \\Delta, x : S \\vdash P \\triangleright \\triangleright \\) and \\( u \\notin \\text{dom}(\\Gamma, \\Delta) \\) implies \\( \\Gamma; \\Delta, u : S \\vdash P \\{ y/x \\} \\triangleright \\triangleright \\).\n\nLemma A.3 (Shared environment weakening). If \\( \\Gamma; \\Delta \\vdash P \\triangleright \\triangleright \\) then \\( x : C \\rightarrow \\circ ; \\Delta \\vdash P \\triangleright \\triangleright \\) and \\( \\Gamma, u : \\langle U \\rangle ; \\Delta \\vdash P \\triangleright \\triangleright \\).\n\nLemma A.4 (Shared environment strengthening). If \\( \\Gamma; \\Delta \\vdash P \\triangleright \\triangleright \\) and \\( x \\notin \\text{fn}(P) \\) then \\( \\Gamma \\setminus x ; \\Delta \\vdash P \\triangleright \\triangleright \\).\n\nIf \\( \\Gamma; \\Delta \\vdash P \\triangleright \\triangleright \\) and \\( u \\notin \\text{fn}(P) \\) then \\( \\Gamma \\setminus u ; \\Delta \\vdash P \\triangleright \\triangleright \\).\nA.2 Proof of Thm. 3.10\n\nProof. By mutual induction on the structure of $P$ and $V$. The proof of the output case in Part (1) relies on Parts (2) and (3), whereas the proof of Parts (2) and (3) relies on Part (1). We analyze each part of the theorem separately, following the definition of $B^k_x(\\cdot)$ in Tab. 1:\n\n1. By assumption, $\\Gamma; \\Lambda; \\Delta \\vdash P$. We consider six cases, depending on the shape of $P$:\n a. Case $P = \\{\\text{Nil}\\}$. The only rule that can be applied here is Nil. By inversion of this rule, we have: $\\Gamma; \\emptyset; \\emptyset \\vdash \\{\\text{Nil}\\}$. We shall then prove the following judgment:\n $$ \\forall \\gamma : \\emptyset; \\emptyset \\triangleright \\{\\text{Nil}\\} $$\n where $\\gamma = (x_0, \\ldots, x_n)$ and $\\Gamma = \\{x_i : \\text{Var}\\}$.\n $$ \\text{(5)} $$\n where $\\gamma = (x_0, \\ldots, x_n)$ and $\\Gamma = \\{x_i : \\text{Var}\\}$.\n\n b. Case $P = u_i ?(y).P'$. We distinguish two sub-cases: (i) $u_i \\in \\text{dom}(\\Delta)$ and (ii) $u_i \\notin \\text{dom}(\\Gamma)$. We consider sub-case (i) first. For this case Rule Rcv can be applied:\n $$ \\Gamma; \\Delta', u_i : S \\vdash P' \\triangleright \\emptyset \\quad \\Gamma; \\Delta' \\vdash y \\triangleright U $$\n Let $\\gamma = \\Gamma \\setminus \\Delta'$ and $\\Theta_1$ be a balanced environment such that\n $$ \\text{dom}(\\Theta_1) = \\{c_{k+1}, \\ldots, c_{k+n}\\} \\cup \\{\\gamma_k, \\ldots, \\gamma_n\\} $$\n and $\\Theta_1(c_{k+1}) = \\bowtie(\\tilde{M}'; \\text{end})$ where $\\tilde{M}' = (G(\\Gamma), G(\\Lambda_1))(\\tilde{\\gamma})$. Then, by IH on the first assumption of (6) we know:\n $$ \\forall \\gamma : \\emptyset; \\emptyset \\triangleright \\{\\text{Nil}\\} $$\n By Def. 3.2 and Def. 3.4 and the second assumption of (6) we have:\n $$ \\forall \\gamma : \\emptyset; \\emptyset \\triangleright \\{\\text{Nil}\\} $$\n where\n $$ \\Theta' = c_k : \\bowtie(\\tilde{M}); \\text{end}, c_{k+1} : \\bowtie(\\tilde{M}'); \\text{end} $$\n with $\\tilde{M} = (G(\\Gamma), G(\\Lambda_1 \\setminus \\Lambda_2))(\\tilde{\\gamma})$. By Def. 3.5, $|P| = |P'| + 1$ so\n $$ \\text{dom}(\\Theta) = \\{c_{k+1}, \\ldots, c_{k+n}\\} \\cup \\{c_k, \\ldots, c_{k-n-1}\\} $$\n and $\\Theta$ is balanced since $\\Theta(c_{k+1})$ dual $\\Theta(c_{k+1})$ and $\\Theta_1$ is balanced. By Tab. 1:\n $$ \\forall \\gamma : \\emptyset; \\emptyset \\triangleright \\{\\text{Nil}\\} $$\n where\n $$ \\Theta' = c_k : \\bowtie(\\tilde{M}); \\text{end}, c_{k+1} : \\bowtie(\\tilde{M}'); \\text{end} $$\n with $\\tilde{M} = (G(\\Gamma), G(\\Lambda_1 \\setminus \\Lambda_2))(\\tilde{\\gamma})$. By Def. 3.5, $|P| = |P'| + 1$ so\n $$ \\text{dom}(\\Theta) = \\{c_{k+1}, \\ldots, c_{k+n}\\} \\cup \\{c_k, \\ldots, c_{k-n-1}\\} $$\n and $\\Theta$ is balanced since $\\Theta(c_{k+1})$ dual $\\Theta(c_{k+1})$ and $\\Theta_1$ is balanced. By Tab. 1:\n $$ \\forall \\gamma : \\emptyset; \\emptyset \\triangleright \\{\\text{Nil}\\} $$\n where\n $$ \\Theta' = c_k : \\bowtie(\\tilde{M}); \\text{end}, c_{k+1} : \\bowtie(\\tilde{M}'); \\text{end} $$\n with $\\tilde{M} = (G(\\Gamma), G(\\Lambda_1 \\setminus \\Lambda_2))(\\tilde{\\gamma})$. By Def. 3.5, $|P| = |P'| + 1$ so\n $$ \\text{dom}(\\Theta) = \\{c_{k+1}, \\ldots, c_{k+n}\\} \\cup \\{c_k, \\ldots, c_{k-n-1}\\} $$\n and $\\Theta$ is balanced since $\\Theta(c_{k+1})$ dual $\\Theta(c_{k+1})$ and $\\Theta_1$ is balanced. By Tab. 1:\nLet $\\Gamma_1 = \\Gamma \\setminus \\vec{x}$. We shall prove the following judgment:\n\n$$\\mathcal{G}(\\Gamma_1 \\setminus y); \\emptyset; \\mathcal{G}(\\Delta', u_i : (?U); S), \\Theta \\vdash B_{\\mathcal{E}}^{k+1}(u_i; (?y).P')$$\n\nThe left-hand side component of $B_{\\mathcal{E}}^{k+1}(u_i; (?y).P')$ is typed using some auxiliary derivations:\n\n(9) $\\frac{\\text{End} \\quad \\mathcal{G}(\\Gamma); \\emptyset; \\emptyset \\vdash 0 \\triangleright \\varnothing}{\\mathcal{G}(\\Gamma); \\emptyset; \\mathcal{G}(\\Lambda_1); \\emptyset \\vdash \\vec{x} \\triangleright M'}$\n\n(10) $\\frac{\\text{End} \\quad \\mathcal{G}(\\Gamma); \\mathcal{G}(\\Lambda_1), \\mathcal{G}(\\Lambda_2); c_{k+1} : !(M'); \\text{end} \\vdash c_{k+1}(\\vec{x}'.0 \\triangleright \\varnothing) \\quad \\mathcal{G}(\\Gamma); \\emptyset; \\mathcal{G}(\\Lambda_1); \\emptyset \\vdash \\vec{x} \\triangleright M'}{\\mathcal{G}(\\Gamma); \\emptyset; \\mathcal{G}(\\Lambda_1) \\setminus \\Lambda_2; u_i : ![\\mathcal{G}(U)]; \\text{end}, c_k : \\text{end} \\vdash u_i(?y).c_{k+1}(\\vec{x}'.0 \\triangleright \\varnothing)$\n\nThe following tree proves this case:\n\n(11) $\\frac{\\text{End} \\quad \\mathcal{G}(\\Gamma_1 \\setminus y); \\emptyset; \\mathcal{G}(\\Lambda_1) \\setminus \\Lambda_2; u_i : ![\\mathcal{G}(U)]; \\text{end}, c_k : \\text{end} \\vdash u_i(?y).c_{k+1}(\\vec{x}'.0 \\triangleright \\varnothing) \\quad \\text{PolyVar} \\quad \\mathcal{G}(\\Gamma_1 \\setminus y); \\emptyset; \\emptyset \\vdash \\vec{x} \\triangleright M}{\\mathcal{G}(\\Gamma_1 \\setminus y); \\emptyset; u_i : ![\\mathcal{G}(U)]; \\text{end}, \\Theta' \\vdash c_k(?\\vec{x}), u_i(?y).c_{k+1}(\\vec{x}'.0 \\triangleright \\varnothing)$\n\nThe following tree proves this case:\n\n(12) $\\frac{\\text{Par} \\quad \\mathcal{G}(\\Gamma_1 \\setminus y); \\emptyset; \\mathcal{G}(\\Delta', u_{i+1} : S), \\Theta_1 \\vdash B_{\\mathcal{E}}^{k+1}(P'; u_{i+1}/u_i)) \\triangleright \\varnothing}{\\mathcal{G}(\\Delta', u_{i+1} : S); \\{\\vec{y}/\\vec{u}\\} = \\mathcal{G}(\\Delta', u_{i+1} : S) \\quad \\mathcal{B}_{\\mathcal{E}}^{k+1}(P'; \\{\\vec{y}/\\vec{u}\\}) = \\mathcal{B}_{\\mathcal{E}}^{k+1}(P'; u_{i+1}/u_i))$\n\nwhere $\\vec{u} = (u_{i+1}, \\ldots, u_{i+|\\mathcal{G}(S)|-1})$ and $\\vec{y} = (u_1, \\ldots, u_{i+|\\mathcal{G}(S)|-1})$. We may notice that if $y \\in \\text{fv}(P')$ then $\\Gamma_1' = \\Gamma_1 \\setminus y$. On the other hand, when $y \\notin \\text{fv}(P')$ then $\\Gamma_1' = \\Gamma_1$ so we need to apply Lem. A.4 with $y$ after Lem. A.2 to (7) in (12). Note that we have used the following for the right assertion of (12):\n\n$$\\mathcal{G}(\\Delta', u_{i+1} : S); \\{\\vec{y}/\\vec{u}\\} = \\mathcal{G}(\\Delta', u_{i+1} : S) \\quad \\mathcal{B}_{\\mathcal{E}}^{k+1}(P'; \\{\\vec{y}/\\vec{u}\\}) = \\mathcal{B}_{\\mathcal{E}}^{k+1}(P'; u_{i+1}/u_i))$$\n\nThis concludes sub-case (i). We now consider sub-case (ii), i.e., $u_i \\in \\text{dom}(\\Gamma)$. Here Rule Acc can be applied:\n\n(13) $\\frac{\\text{Acc} \\quad \\Gamma; \\emptyset \\vdash u_i \\triangleright \\langle U \\rangle \\quad \\Gamma; \\Lambda_1; \\Delta \\vdash P' \\triangleright \\varnothing \\quad \\Gamma; \\Lambda_2; \\emptyset \\vdash y \\triangleright U}{\\Gamma \\setminus y; \\Lambda_1 \\setminus \\Lambda_2; \\Delta \\vdash u_i(?y).P' \\triangleright \\varnothing}$\n\nLet $\\vec{x} = \\text{fv}(P)$ and $\\vec{x}' = \\text{fv}(P')$. Furthermore, let $\\Theta_1$, $\\Theta$, $\\Gamma_1$, and $\\Gamma_1'$ be defined as in sub-case (i). By IH on the second assumption of (13) we have:\n\n(14) $\\frac{\\mathcal{G}(\\Gamma_1'); \\emptyset; \\mathcal{G}(\\Delta), \\Theta_1 \\vdash \\mathcal{B}_{\\mathcal{E}}^{k+1}(P') \\triangleright \\varnothing}{\\mathcal{G}(\\Gamma_1); \\emptyset; \\mathcal{G}(\\Delta), \\Theta_1 \\vdash \\mathcal{B}_{\\mathcal{E}}^{k+1}(P') \\triangleright \\varnothing}$\nBy Def. 3.2 and Def. 3.4 and the first assumption of (13) we have:\n\\[ \\mathcal{G}(\\Gamma); \\emptyset; \\emptyset \\vdash u_i : \\mathcal{G}(U) \\] \n(15)\n\nBy Def. 3.2, Def. 3.4, and the third assumption of (13) we have:\n\\[ \\mathcal{G}(\\Gamma); \\mathcal{G}(\\Lambda_2); \\emptyset \\vdash y : \\mathcal{G}(U) \\] \n(16)\n\nBy Tab. 1, we have:\n\\[ \\mathcal{G}(\\Gamma_1 \\setminus y); \\emptyset; \\mathcal{G}(\\Lambda_1) \\vdash \\mathcal{B}_k^i(u_i?y, P') \\triangleright \\Diamond \\] \n(18)\n\nTo this end, we use some auxiliary derivations:\n\n\\[ \\begin{align*}\n\\text{End} & \\quad \\frac{\\mathcal{G}(\\Gamma); \\emptyset; \\emptyset \\vdash \\omega \\triangleright \\Diamond}{\\mathcal{G}(\\Gamma); \\emptyset; \\emptyset \\vdash \\omega \\triangleright \\Diamond} \\\\\n\\text{PolySend} & \\quad \\frac{\\mathcal{G}(\\Gamma); c_k+1 : \\text{end} \\vdash \\omega \\triangleright \\Diamond}{\\mathcal{G}(\\Gamma); \\emptyset \\vdash c_k+1 \\triangleright \\Diamond} \\\\\n\\text{PolyRec} & \\quad \\frac{\\mathcal{G}(\\Gamma) \\vdash \\mathcal{G}(\\Lambda_1) \\setminus \\Lambda_2; \\emptyset \\vdash \\omega \\triangleright \\Diamond}{\\mathcal{G}(\\Gamma) \\vdash \\mathcal{G}(\\Lambda_1) \\setminus \\Lambda_2; \\emptyset \\vdash \\omega \\triangleright \\Diamond} \\\\\n\\text{PolyVar} & \\quad \\frac{\\mathcal{G}(\\Gamma); \\emptyset \\vdash \\omega \\triangleright \\Diamond}{\\mathcal{G}(\\Gamma); \\emptyset \\vdash \\omega \\triangleright \\Diamond}\n\\end{align*} \\] \n(19)\n\nThe following tree proves this sub-case:\n\n\\[ \\begin{align*}\n\\text{Par} & \\quad \\frac{\\mathcal{G}(\\Gamma_1 \\setminus y); \\emptyset; \\mathcal{G}(\\Delta); \\emptyset \\vdash \\omega \\triangleright \\Diamond}{\\mathcal{G}(\\Gamma_1 \\setminus y); \\emptyset; \\Theta \\vdash \\omega \\triangleright \\Diamond}\n\\end{align*} \\] \n(22)\n\nAs in sub-case (i), we may notice that if \\( y \\in \\text{fv}(P') \\) then \\( \\Gamma' \\vdash \\Gamma_1 \\setminus y \\). On the other hand, if \\( y \\notin \\text{fv}(P') \\) then \\( \\Gamma' = \\Gamma_1 \\setminus y \\) so we need to apply Lem. A.4 with \\( y \\) to (14) in (22). This concludes the analysis for the input case \\( P = u_i?y, P' \\).\n\n\\subsection*{c. Case \\( P = u_i!V, P' \\).}\n\nWe distinguish two sub-cases: (i) \\( u_i \\in \\text{dom}(\\Delta) \\) and (ii) \\( u_i \\in \\text{dom}(\\Gamma) \\). We consider sub-case (i) first. For this case Rule \\text{SEND} can be applied:\n\n\\[ \\begin{align*}\n\\text{Send} & \\quad \\frac{\\Gamma; \\Lambda_1; \\Delta_1 \\vdash P' \\triangleright \\Diamond}{\\Gamma; \\Lambda_1; \\Delta_2 \\vdash V \\triangleright P' \\triangleright \\Diamond} \\\\\n& \\quad \\frac{\\Gamma; \\Lambda_1; \\Delta_2 \\triangleright \\{u_i : S\\}; \\emptyset \\vdash \\omega \\triangleright \\Diamond}{\\Gamma; \\Lambda_1; \\Delta_2 \\triangleright \\{u_i : S\\}; \\emptyset \\vdash \\omega \\triangleright \\Diamond}\n\\end{align*} \\] \n(23)\n\nLet \\( \\bar{z} = \\text{fv}(P') \\) and \\( l = |V| \\). Also, let \\( \\Gamma' = \\Gamma \\setminus \\bar{z} \\) and \\( \\Theta_1 \\) be a balanced environment such that\n\\[ \\text{dom}(\\Theta_1) = \\{ e_k, e_k+1, \\ldots, e_{k+l+|P'|} \\} \\cup \\{ c_k, c_k+1, \\ldots, c_{k+l+|P'|} \\} \\]\nand \\( \\Theta_1(c_{k+l+1}) = \\emptyset(M_1) \\); where \\( M_1 = (\\mathcal{G}(\\Gamma), \\mathcal{G}(\\Lambda_1))(\\bar{z}) \\).\n\nThen, by IH on the first assumption of (23) we have:\n\\[ \\mathcal{G}(\\Gamma'_1); \\emptyset; \\mathcal{G}(\\Delta_1), \\Theta_1 \\vdash \\mathcal{B}_k^{i+l+1}(P') \\triangleright \\Diamond \\] \n(24)\nLet \\( \\tilde{y} = \\text{fv}(V) \\) and \\( \\Gamma_2' = \\Gamma \\setminus \\tilde{y} \\). There are two cases: \\( U = C \\rightarrow \\circ \\) or \\( U = C \\rightarrow \\circ \\). We consider the first case. If \\( U = C \\rightarrow \\circ \\) then let \\( \\Theta_2 \\) be a balanced environment such that\n\n\\[\n\\text{dom}(\\Theta_2) = \\{c_{k+1}, \\ldots, c_{k+|V|} \\} \\cup \\{\\bar{c}_{k+i_1}, \\ldots, \\bar{c}_{k+i_1}|V|\\}\n\\]\n\n\\( \\Theta_2(c_{k+1}) = ?(\\bar{M}_2) \\); \\( \\text{end} \\), and \\( \\Theta_2(\\bar{c}_{k+i_1}) = !(\\bar{M}_2) \\); \\( \\text{end} \\) where \\( \\bar{M}_2 = (G(\\Gamma), G(\\Lambda_2))(\\tilde{y}) \\). Then, by IH (Part 2) on the second assumption of (23) we have:\n\n\\[\nG(\\Gamma); G(\\Delta_2). \\Theta_2 \\vdash \\mathcal{V}_y^{k+1}(V) \\triangleright G(U)\n\\]\n\nWe comment the second case for \\( \\Theta \\). We know \\( \\Theta \\) and \\( \\Delta \\) are balanced. By Tab. 1, we have:\n\nBy construction \\( \\Theta(\\bar{c}_{k+i}) \\) dual \\( \\Theta(\\bar{c}_{k+i+1}) \\) and \\( \\Theta_1 \\) and \\( \\Theta_2 \\) are balanced. By Tab. 1, we have:\n\n\\[\n(25)\n\\]\n\nWe know \\( \\text{fv}(P') \\subseteq \\text{fv}(P) \\) and \\( \\text{fv}(P) \\subseteq \\text{fv}(V) \\) that is \\( \\bar{z} \\subseteq \\bar{x} \\) and \\( \\tilde{y} \\subseteq \\bar{x} \\). Let \\( \\Gamma_1 = \\Gamma \\setminus \\bar{x} \\). We shall prove the following judgment:\n\n\\[\nG(\\Gamma_1); \\emptyset; G(((\\Delta_1, \\Delta_2) \\setminus \\{u_i : S\\}), u_i !((U); S), \\emptyset) \\vdash B_k^L(u_i !((V).P')). \\triangleright \\circ\n\\]\n\nLet \\( \\sigma = \\{u_i'll_i\\} \\). To type the left-hand side component of \\( B_k^L(u_i !((V).P')) \\) we use some auxiliary derivations:\n\n\\[\n(27)\n\\]\n\n\\[\n(28)\n\\]\n\n\\[\n(29)\n\\]\n11:34 Minimal Session Types\n\n\\[ \\text{PolySend} \\quad \\frac{G(\\Gamma); \\emptyset \\vdash \\beta : \\tilde{M}}{G(\\Gamma); \\emptyset; \\tilde{\\text{v}}_{k+1} : \\tilde{\\text{M}}} \\quad (35) \\]\n\n\\[ \\text{PolyVar} \\quad \\frac{G(\\Gamma); \\emptyset \\vdash \\beta : \\tilde{M}}{G(\\Gamma); \\emptyset; \\text{cl}_{k+1} : !\\tilde{\\text{M}}} \\quad (36) \\]\n\nThe following tree proves this case:\n\n\\[ \\text{Par} \\quad \\frac{G(\\Gamma_1); \\emptyset; G(((1, \\Delta_2) \\setminus \\{u_i : S\\}), u_i :: (U); S), \\emptyset \\vdash B^{k+1}_2 (u_i (V), P') \\triangleright \\circ \\triangleright \\circ}{G(\\Gamma_1); \\emptyset; G(\\Delta_1, \\emptyset), \\emptyset \\vdash B^{k+1}_2 (P') \\triangleright \\circ \\triangleright \\circ} \\quad (30) \\]\n\n\\[ \\text{Lem. A.2) with } \\{\\tilde{\\text{u}}_i / \\tilde{\\text{u}}_i \\} \\]\n\n\\[ \\text{Lem. A.4) with } \\tilde{x} \\setminus \\emptyset \\]\n\nwhere \\( \\tilde{n} = (u_{i+1}, \\ldots, u_{i+|G(S)|}) \\) and \\( \\tilde{u} = (u_i, \\ldots, u_{i+|G(S)|-1}) \\).\n\nWe consider sub-case (ii). For this sub-case Rule \\text{Req} can be applied:\n\n\\[ \\text{Req} \\quad \\frac{G(\\Gamma_1); \\emptyset; \\emptyset \\vdash u \\triangleright (U) \\quad G(\\Gamma_1); \\emptyset; \\emptyset \\vdash u \\triangleright (V) \\quad \\emptyset \\vdash V \\triangleright U}{G(\\Gamma_1); \\emptyset; \\emptyset \\vdash u \\triangleright (V). P' \\triangleright \\circ \\triangleright \\circ} \\quad (32) \\]\n\nLet \\( \\tilde{z} = \\text{fv}(P') \\) and \\( l = |V| \\). Further, let \\( \\Gamma'_1 = \\Gamma \\setminus \\tilde{z} \\) and let \\( \\Theta_1 \\) and \\( \\Theta_2 \\) be environments defined as in sub-case (i).\n\nBy IH on the second assumption of (32) we have:\n\n\\[ G(\\Gamma'_1); \\emptyset; G(\\Delta_1), \\emptyset \\vdash B^{k+1}_2 (P') \\triangleright \\circ \\triangleright \\circ \\quad (33) \\]\n\nLet \\( \\tilde{y} = \\text{fv}(V) \\). By IH on the second assumption of (23) we have:\n\n\\[ G(\\Gamma); \\emptyset; G(\\Delta_2), \\emptyset \\vdash v^{k+1}_b (V) \\triangleright G(U) \\quad (34) \\]\n\nLet \\( \\tilde{x} = \\text{fv}(P) \\) and \\( \\Gamma_1 = \\Gamma \\setminus \\tilde{x} \\). We define \\( \\Theta = \\Theta_1, \\Theta_2, \\Theta' \\), where:\n\n\\[ \\Theta' = c_k : ?(\\tilde{M}); \\text{end}, c_{k+1} : ?(\\tilde{M}); \\text{end} \\]\n\nwith \\( \\tilde{M} = (G(\\Gamma), G(\\Delta))(\\tilde{x}) \\). By Def. 3.5, we know \\( |P| = |V| + |P'| + 1 \\), so\n\n\\[ \\text{dom}(\\Theta) = (c_k, \\ldots, c_{k+|P|-1}) \\cup (c_k, \\ldots, c_{k+|P'|-1}) \\]\n\nBy construction \\( \\Theta \\) is balanced since \\( \\Theta(c_{k+t}) \\) dual \\( (\\tilde{M}_{k+t}) \\) and \\( \\Theta_1 \\) and \\( \\Theta_2 \\) are balanced. By Tab. 1, we have:\n\n\\[ B^{k+1}_2 (u_i (V), P') = c_{k+1}(\\tilde{x}), u_i (v^{k+1}_b (V)). \\tilde{\\text{z}}_{k+t+1}(\\tilde{M}_2), \\emptyset \\vdash B^{k+1}_2 (P') \\]\n\nWe know \\( \\text{fv}(P') \\subseteq \\text{fv}(P) \\) and \\( \\text{fv}(V) \\subseteq \\text{fv}(P) \\) that is \\( \\tilde{z} \\subseteq \\tilde{x} \\) and \\( \\tilde{y} \\subseteq \\tilde{x} \\).\n\nTo prove that \\( G(\\Gamma_1); \\emptyset; G(\\Delta_1, \\Delta_2), \\emptyset \\vdash B^{k+1}_2 (u_i (V), P') \\), we use some auxiliary derivations:\n\n\\[ \\text{End} \\quad \\frac{G(\\Gamma); \\emptyset \\vdash 0 \\triangleright \\circ}{G(\\Gamma); \\emptyset; \\text{cl}_{k+t+1} : \\text{end} \\vdash 0 \\triangleright \\circ} \\quad (35) \\]\n\n\\[ \\text{PolySend} \\quad \\frac{G(\\Gamma_1); \\emptyset; \\text{cl}_{k+t+1} : \\text{end} \\vdash 0 \\triangleright \\circ}{G(\\Gamma_1); \\emptyset; \\tilde{\\text{M}}_{k+t+1}; \\text{end} \\vdash \\tilde{\\text{M}}_{k+t+1}(\\tilde{z}), 0 \\triangleright \\circ} \\quad (36) \\]\n\n\\[ \\text{PolyVar} \\quad \\frac{G(\\Gamma_1); \\emptyset; \\tilde{\\text{M}}_{k+t+1}; \\text{end} \\vdash u_i (v^{k+1}_b (V)). \\tilde{\\text{z}}_{k+t+1}(\\tilde{M}_2), 0 \\triangleright \\circ}{G(\\Gamma_1); \\emptyset; \\tilde{\\text{M}}_{k+t+1}; \\text{end} \\vdash u_i (V), 0 \\triangleright \\circ} \\quad (37) \\]\nWe use auxiliary derivation:\n\n\\[ \\text{We shall prove the following judgment:} \\]\n\n\\[ \\Theta \\vdash c_k(\\bar{x}).u_i!(V_k+1(V)) \\cdot \\bar{x}_k+1! \\Gamma \\]\n\nThe following tree proves this case:\n\n\\[ \\text{This concludes the analysis for the output case } P = u_i!(\\langle V \\rangle).P'. \\] We remark that the proof for the case when \\( V = y \\) is specialization of above the proof where \\( l = |y| = 0, \\) \\( \\bar{y} = f\\nu(y) = y, V^{k+1}(y) = y \\) and it holds that \\( y\\sigma = y. \\)\n\nd. Case \\( P = V u_i. \\) For this case only Rule \\text{App} can be applied:\n\n\\[ \\text{We distinguish two sub-cases based on the higher-order type: (i) } \\bar{x} \\rightarrow^* \\bar{y} \\text{ or (ii) } \\bar{x} \\rightarrow^* \\bar{y}. \\]\n\nWe consider sub-case (i) first. Let \\( \\bar{x} = f\\nu(V) \\) and let \\( \\Theta_1 \\) be a balanced environment such that\n\n\\[ \\text{dom}(\\Theta_1) = \\{c_{k+1}, \\ldots, c_{k+|V|}\\} \\cup \\{\\bar{e}_{k+1}, \\ldots, \\bar{e}_{k+|V|}\\} \\]\n\nand \\( \\Theta_1(c_{k+1}) = ?(\\bar{M}); \\text{end} \\) and \\( \\Theta_1(\\bar{e}_{k+1}) = !(\\bar{M}); \\text{end} \\) where \\( \\bar{M} = (G(\\Gamma), G(\\Lambda))(\\bar{x}). \\)\n\nThen, by IH (Part 2) on the second assumption of (39) we have:\n\n\\[ G(\\Gamma); G(\\Lambda); \\Theta_1 \\vdash V^{k+1}(V) \\triangleright G(U) \\]\n\nBy Def. 3.2 and Def. 3.4 and (39) we have:\n\n\\[ G(\\Gamma); G(\\Delta_2) \\vdash \\bar{m} \\triangleright G(C) \\]\n\nwhere \\( \\bar{m} = (u_i, \\ldots, u_i+|G(C)|-1). \\) We define \\( \\Theta = \\Theta_1, c_k : ?(\\bar{M}); \\text{end}. \\) By Def. 3.5, \\( |P| = |V| + 1 \\) so \\( \\text{dom}(\\Theta) = \\{c_k, \\ldots, c_{k+|P|}-1\\} \\cup \\{\\bar{e}_{k+1}, \\ldots, \\bar{e}_{k+|P|-1}\\}. \\) By construction \\( \\Theta \\) is balanced since \\( \\Theta_1 \\) is balanced.\n\nBy Tab. 1, we have:\n\n\\[ B^k_\\bar{x}(V u_i) = c_k(\\bar{x}).V^{k+1}_\\bar{x}(V) \\bar{m} \\]\n\nWe shall prove the following judgment:\n\n\\[ G(\\Gamma_1); G(\\Delta_1, \\Delta_2) \\vdash c_k(\\bar{x}).V^{k+1}_\\bar{x}(V) \\bar{m} \\triangleleft \\]\n\nWe use auxiliary derivation:\n\n\\[ G(\\Gamma_1); G(\\Delta_1, \\Delta_2) \\vdash V^{k+1}_\\bar{x}(V) \\bar{m} \\triangleleft \\]\n\nThe following tree proves this case:\nIn applying (40) and (41) we may notice that by Def. 3.2: \\( \\mathcal{G}(U) = \\mathcal{G}(C) \\rightarrow \\circ \\). This concludes sub-case (i).\n\nWe now consider sub-case (ii). For this case we know that \\( \\Lambda = \\emptyset \\) and \\( \\Delta_1 = \\emptyset \\) in (39). Let \\( \\tilde{x} = \\text{fv}(V) \\). Then, by IH (Part 3) on the second assumption of (39) we have:\n\n\\[\n\\mathcal{G}(\\Gamma); \\emptyset \\vdash \\nu_s(\\tilde{x}); \\nu_s^{k+1}(V) \\tilde{m} \\circ \n\\]\n\nBy Def. 3.2, Def. 3.4, and (39) we have:\n\n\\[\n\\mathcal{G}(\\Gamma); \\emptyset; \\mathcal{G}(\\Delta_2) \\vdash \\tilde{m} \\circ \\mathcal{G}(C)\n\\]\n\nwhere \\( \\tilde{m} = (u_1, \\ldots, u_{i+\\mathcal{G}(C)-1}) \\). By Tab. 1, we have:\n\n\\[\n\\mathcal{E}_x^k(V u_i) = c_k(\\tilde{x}); \\nu_s^{k+1}(V) \\tilde{m}\n\\]\n\nWe define \\( \\Theta = c_k \\vdash (\\tilde{M}) \\); \\textbf{end} with \\( \\tilde{M} = \\mathcal{G}(\\Gamma)(\\tilde{x}) \\).\n\nWe shall prove the following judgment:\n\n\\[\n\\mathcal{G}(\\Gamma_1); \\emptyset; \\mathcal{G}(\\Delta_2), \\Theta \\vdash c_k(\\tilde{x}); \\nu_s^{k+1}(V) \\tilde{m} \\circ \n\\]\n\nThe following tree proves this case:\n\n\\[\n\\text{PolyApp} \\quad \\frac{\\text{PolyVar}}{\\mathcal{G}(\\Gamma); \\emptyset \\vdash \\nu_s^{k+1}(V) \\tilde{m} \\circ} \n\\]\n\n\\[\n\\text{PolyRecv} \\quad \\frac{\\text{PolyVar}}{\\mathcal{G}(\\Gamma); \\emptyset \\vdash \\nu_s^{k+1}(V) \\tilde{m} \\circ} \n\\]\n\nIn applying (46) and (41) we may notice that by Def. 3.2: \\( \\mathcal{G}(U) = \\mathcal{G}(C) \\rightarrow \\circ \\). We remark that the proof for the case when \\( y \\) is specialization of above the proof where \\( r = |y| = 0, \\tilde{x} = \\text{fv}(y) = y, \\nu_s^{k+1}(y) = y \\) and it holds that \\( y \\sigma = y \\).\n\ne. Case \\( P = \\langle \\nu s : C \\rangle P' \\). We distinguish two sub-cases: (i) \\( C = S \\) and (ii) \\( C = \\langle U \\rangle \\).\n\nFirstly, we \\( \\alpha \\)-convert \\( P \\) as follows:\n\n\\[\nP \\equiv_{\\alpha} \\langle \\nu s_1 : C \\rangle P'\\{s_1 \\overline{s}/s\\}\n\\]\n\nWe consider sub-case (i) first. For this case Rule Ress can be applied:\n\n\\[\n\\text{ResS} \\quad \\frac{\\Gamma; \\Lambda; \\Delta, s_1 : S, \\overline{s} : \\overline{S} \\vdash P'\\{s_1 \\overline{s}/s\\} \\circ \\circ}{\\Gamma; \\Lambda; \\Delta \\vdash \\langle \\nu s_1 : S \\rangle P'\\{s_1 \\overline{s}/s\\} \\circ \\circ}\n\\]\n\nLet \\( \\tilde{x} = \\text{fv}(P') \\) and let \\( \\Theta_1 \\) be a balanced environment such that\n\n\\[\n\\text{dom}(\\Theta_1) = \\{c_k, \\ldots, c_{k+|P'|-1}\\} \\cup \\{c_{k+1}, \\ldots, c_{k+|P'|-1}\\}\n\\]\nand \\( \\Theta_1(c_k) = \\odot(\\tilde{M}) \\); end with \\( \\tilde{M} = (G(\\Gamma), G(\\Lambda))(\\tilde{x}) \\). Then, by IH on the assumption of (51) we have:\n\n\\[\nG(\\Gamma); \\emptyset; G(\\Delta, s_1 : S, \\bar{s}_1 : \\bar{S}), \\Theta_1 \\vdash B^k_{\\bar{x}}(P'\\{s_1\\bar{s}_1/S\\}) \\triangleright \\odot\n\\] \n\n(52)\n\nNote that we take \\( \\Theta = \\Theta_1 \\) since \\( fv(P) = fv(P') \\) and \\( |P| = |P'| \\). By Def. 3.2 and Def. 3.4 and (56), we know that:\n\n\\[\n\\begin{align*}\nG(\\Gamma); \\emptyset; G(\\Delta, \\tilde{s} : G(S), \\bar{s} : G(\\bar{S})) & \\vdash B^k_{\\bar{x}}(P'\\{s_1\\bar{s}_1/S\\}) \\triangleright \\odot \\\\\n\\end{align*}\n\\] \n\n(53)\n\nwhere \\( \\tilde{s} = (s_1, \\ldots, s_{|G(S)|}) \\) and \\( \\bar{s} = (\\bar{s}_1, \\ldots, \\bar{s}_{|G(\\bar{S})|}) \\). By Tab. 1, we have:\n\n\\[\nB^k_{\\bar{x}}((\\nu s)P') = (\\nu \\tilde{s} : G(S))B^k_{\\bar{x}}(P'\\{s_1\\bar{s}_1/S\\})\n\\]\n\nThe following tree proves this sub-case:\n\n\\[\n\\begin{array}{c}\n\\text{PolyResS} \\\\\nG(\\Gamma); \\emptyset; G(\\Delta) \\vdash (\\nu \\tilde{s} : G(S))B^k_{\\bar{x}}(P'\\{s_1\\bar{s}_1/S\\}) \\triangleright \\odot\n\\end{array}\n\\]\n\n(54)\n\nWe now consider sub-case (ii). Similarly to sub-case (i) we first \\( \\alpha \\)-convert \\( P \\) as follows:\n\n\\[\nP \\equiv_{\\alpha} (\\nu s_1)P'\\{s_1/s\\}\n\\]\n\nFor this sub-case Rule \\( \\text{Res} \\) can be applied:\n\n\\[\n\\begin{array}{c}\n\\text{Res} \\\\\n\\Gamma, s_1 : \\langle U \\rangle; \\Delta ; \\emptyset \\triangleright P'\\{s_1/s\\} \\triangleright \\odot\n\\end{array}\n\\]\n\n(55)\n\nLet \\( \\bar{x} = fv(P') \\) and let \\( \\Theta_1 \\) be defined as in sub-case (i). By IH on the first assumption of (55) we have:\n\n\\[\n\\begin{align*}\nG(\\Gamma, s_1 : \\langle U \\rangle); \\emptyset; G(\\Delta), \\Theta_1 & \\vdash B^k_{\\bar{x}}(P'\\{s_1/s\\}) \\triangleright \\odot \\\\\n\\end{align*}\n\\] \n\n(56)\n\nHere we also take \\( \\Theta = \\Theta_1 \\) since \\( fv(P) = fv(P') \\) and \\( |P| = |P'| \\). We notice that by Def. 3.2 and Def. 3.4 and (56):\n\n\\[\nG(\\Gamma), s_1 : G(\\langle U \\rangle); \\emptyset; G(\\Delta), \\Theta_1 \\vdash B^k_{\\bar{x}}(P'\\{s_1/s\\}) \\triangleright \\odot\n\\] \n\n(57)\n\nBy Tab. 1, we have:\n\n\\[\nB^k_{\\bar{x}}((\\nu s)P') = (\\nu s_1 : G(\\langle U \\rangle))B^k_{\\bar{x}}(P'\\{s_1/s\\})\n\\]\n\nwhere \\( \\tilde{s} = s_1 \\) since \\( |G(\\langle U \\rangle)| = 1 \\). The following tree proves this sub-case:\n\n\\[\n\\begin{array}{c}\n\\text{Res} \\\\\nG(\\Gamma); \\emptyset; G(\\Delta), \\Theta \\vdash (\\nu s_1 : G(\\langle U \\rangle))B^k_{\\bar{x}}(P'\\{s_1/s\\}) \\triangleright \\odot\n\\end{array}\n\\]\n\n(58)\n\nf. Case \\( P = Q \\mid R \\). For this case only Rule \\( \\text{Par} \\) can be applied:\n\n\\[\n\\begin{array}{c}\n\\text{Par} \\\\\n\\Gamma ; \\Lambda_1 ; \\Delta_1 \\triangleright Q \\triangleright \\odot \\\\\n\\Gamma ; \\Lambda_2 ; \\Delta_2 \\triangleright R \\triangleright \\odot\n\\end{array}\n\\]\n\n(59)\n\nLet \\( \\tilde{y} = fv(Q) \\) and let \\( \\Theta_1 \\) be a balanced environment such that \\( \\text{dom}(\\Theta_1) = \\{c_{k+1}, \\ldots, c_{k+|Q|}\\} \\cup \\{\\tilde{c}_{k+1}, \\ldots, \\tilde{c}_{k+|Q|}\\} \\).\nand \\( \\Theta_1(c_{k+1}) = (?\\bar{M}_1) \\); end with \\( \\bar{M}_1 = (\\mathcal{G}(\\Gamma), \\mathcal{G}(\\Lambda_1))(\\bar{y}) \\). Let \\( \\Gamma'_1 = \\Gamma \\setminus \\bar{y} \\). Then, by IH on the first assumption of (59) we have:\n\n\\[\n\\mathcal{G}(\\Gamma'_1); \\emptyset; \\mathcal{G}(\\Delta_1), \\Theta_1 \\vdash B_{y}^{k+1}(Q) \\triangleright \\bigcirc\n\\]\n\n(60)\n\nLet \\( \\bar{z} = \\mathsf{fv}(R) \\) and \\( l = |Q| \\). Also, let \\( \\Theta_2 \\) be a balanced environment such that\n\n\\[\n\\text{dom}(\\Theta_2) = \\{c_{k+t+1}, \\ldots, c_{k+l+|R|}\\} \\cup \\{c_{k+t+2}, \\ldots, c_{k+l+|R|}\\}\n\\]\n\nand \\( \\Theta_2(c_{k+l+1}) = (?\\bar{M}_2) \\); end with \\( \\bar{M}_2 = (\\mathcal{G}(\\Gamma), \\mathcal{G}(\\Lambda_2))(\\bar{z}) \\).\n\nLet \\( \\Gamma'_2 = \\Gamma \\setminus \\bar{z} \\). Then, by IH on the second assumption of (59) we have:\n\n\\[\n\\mathcal{G}(\\Gamma'_2); \\emptyset; \\mathcal{G}(\\Delta_2), \\Theta_2 \\vdash B_{y}^{k+l+1}(R) \\triangleright \\bigcirc\n\\]\n\n(61)\n\nLet \\( \\bar{x} = \\mathsf{fv}(P) \\) and \\( \\bar{M} = (\\mathcal{G}(\\Gamma), \\mathcal{G}(\\Lambda_1, \\Lambda_2))(\\bar{x}) \\). We may notice that \\( \\bar{M}_i \\subseteq \\bar{M} \\) for \\( i \\in \\{1, 2\\} \\). We define \\( \\Theta = \\Theta_1, \\Theta_2, \\Theta' \\) where:\n\n\\[\n\\Theta' = c_k : (?\\bar{M}); \\text{end}, \\bar{c}_{k+1} : !\\langle \\bar{M}_1 \\rangle; \\text{end}, \\bar{c}_{k+l+1} : !\\langle \\bar{M}_2 \\rangle; \\text{end}\n\\]\n\nBy construction \\( \\Theta \\) is balanced since \\( \\Theta(c_{k+1}) \\) dual \\( \\Theta(\\bar{c}_{k+1}) \\), \\( \\Theta(c_{k+t+1}) \\) dual \\( \\Theta(\\bar{c}_{k+t+1}) \\), and \\( \\Theta_1 \\) and \\( \\Theta_2 \\) are balanced.\n\nBy Tab. 1 we have:\n\n\\[\nB_{y}^{k+1}(Q | R) = c_k ?(\\bar{x}).\\bar{c}_{k+1} !\\langle \\bar{y} \\rangle.\\bar{c}_{k+t+1} !\\langle \\bar{z} \\rangle.0 | B_{y}^{k+1}(Q) | B_{y}^{k+l+1}(R)\n\\]\n\nLet \\( \\Gamma_1 = \\Gamma \\setminus \\bar{x} \\). We shall prove the following judgment:\n\n\\[\n\\mathcal{G}(\\Gamma_1); \\emptyset; \\mathcal{G}(\\Lambda_1, \\Lambda_2), \\Theta \\vdash c_k ?(\\bar{x}).\\bar{c}_{k+1} !\\langle \\bar{y} \\rangle.\\bar{c}_{k+t+1} !\\langle \\bar{z} \\rangle.0 | B_{y}^{k+1}(Q) | B_{y}^{k+l+1}(R) \\triangleright \\bigcirc\n\\]\n\nTo type the trio, which is the left-hand side component, we use some auxiliary derivations:\n\n\\[\n\\begin{array}{c}\n\\text{End} \\quad \\text{Nil} \\\\\n\\mathcal{G}(\\Gamma); \\emptyset; \\emptyset \\vdash 0 \\\\\n\\mathcal{G}(\\Gamma); \\emptyset; \\bar{c}_{k+t+1} : \\text{end} \\vdash 0 \\\\\n\\end{array}\n\\]\n\n(62)\n\n\\[\n\\begin{array}{c}\n\\text{PolySend} \\\\\n\\mathcal{G}(\\Gamma); \\emptyset; \\bar{c}_{k+t+1} : \\text{end} \\vdash 0 \\\\\n\\mathcal{G}(\\Gamma); \\emptyset; \\bar{c}_{k+t+1} !\\langle \\bar{M}_2 \\rangle; \\text{end} \\vdash \\bar{c}_{k+t+1} !\\langle \\bar{z} \\rangle.0 \\triangleright \\bigcirc \\\\\n\\end{array}\n\\]\n\n(63)\n\n\\[\n\\begin{array}{c}\n\\text{PolySend} \\\\\n\\mathcal{G}(\\Gamma); \\emptyset; \\bar{c}_{k+t+1} !\\langle \\bar{M}_2 \\rangle; \\text{end} \\vdash \\bar{c}_{k+t+1} !\\langle \\bar{z} \\rangle.0 \\triangleright \\bigcirc \\\\\n\\end{array}\n\\]\n\n(64)\n\n(65)\nThis is the second case concerning values when 3.\n\nBy Tab. 1 we have\n\n\\[ \\vdash \\Gamma; \\Lambda; \\Delta \\]\n\nHence, we prove the following judgment by applying Rule\n\n\\[ \\text{by Def. 3.2 and Def. 3.4 and the second assumption of (69) we have:} \\]\n\n\\[ \\Theta = \\Theta \\]\n\nFor this case only Rule \\text{Abs} can be applied: \\[ \\text{Abs} \\]\n\n\\[ \\text{Let } \\tilde{x} = \\text{fv}(P) \\text{ and } \\Gamma_1 = \\Gamma \\setminus \\tilde{x}. \\text{ Also, let } \\Theta_1 \\text{ be a balanced environment such that} \\]\n\n\\[ \\text{dom}(\\Theta_1) = \\{c_k, \\ldots, c_{k+|P|-1} \\} \\cup \\{c_{k+1}, \\ldots, c_{k+|P|-1} \\} \\]\n\nand \\( \\Theta_1(c_k) = \\bar{M} \\) with \\( \\bar{M} = (G(\\Gamma \\setminus y_1), G(\\Delta))(\\bar{x}) \\). Then, by IH (Part 1) on the first assumption of (69) we have:\n\n\\[ \\vdash \\Gamma_1; \\Theta_1 \\vdash \\lambda y_1.P[y_1/y] \\]\n\nBy Def. 3.2 and Def. 3.4 and the second assumption of (69) we have:\n\n\\[ \\vdash \\Gamma; \\Theta_2 \\vdash \\bar{y} : G(\\Delta) \\]\n\nwhere \\( \\bar{y} = (y_1, \\ldots, y_{|G(\\Delta)|}) \\).\n\nWe define \\( \\Theta = \\Theta_1, \\bar{T} !!(\\bar{M}); \\text{ end.} \\) By Tab. 1, we have:\n\n\\[ \\forall^k (\\lambda y. P) = \\lambda \\bar{y} : G(\\Delta), \\bar{T} !!(\\bar{x}). \\text{O} \\mid B^k_2(P[y/y]) \\]\n\n2. This is the first case concerning values when \\( V = y \\). By assumption \\( \\Gamma; \\Lambda; \\Delta \\vdash y : C \\rightarrow \\circ \\).\n\nFor this case only Rule \\text{LVAR} can be applied and by inversion \\( \\Delta = \\{y : C \\rightarrow \\circ\\} \\text{ and } \\Lambda = \\emptyset \\).\n\nBy Tab. 1 we have \\( \\forall^k (y) = y \\) and by Def. 3.2 and Def. 3.4 we have \\( G(\\Delta) = \\{G(C \\rightarrow \\circ)\\} \\).\n\nHence, we prove the following judgment by applying Rule \\text{LVAR}:\n\n\\[ \\forall^k (\\Gamma) ; G(\\Delta) ; \\emptyset \\vdash \\forall^k (y) \\rightarrow G(C \\rightarrow \\circ) \\]\n\n3. This is the second case concerning values when \\( V = \\lambda y. P \\). By assumption we have \\( \\Gamma; \\Lambda; \\Delta \\vdash V : C \\rightarrow \\circ \\). Here we distinguish two sub-cases (1) \\( \\rightarrow \\rightarrow \\rightarrow \\circ \\) and (2) \\( \\rightarrow \\rightarrow \\rightarrow \\rightarrow \\circ \\):\n\n\\[ \\rightarrow \\rightarrow \\rightarrow \\circ \\text{. By assumption, } \\Gamma; \\Lambda; \\Delta \\vdash V : C \\rightarrow \\circ. \\text{ In this case Rule \\text{Abs} can be applied. Firstly, we } \\alpha \\text{-convert value } V \\text{ as follows:} \\]\n\n\\[ V \\equiv_\\alpha \\lambda y_1.P[y_1/y] \\]\n\nFor this case only Rule \\text{Abs} can be applied:\n\n\\[ \\text{Abs} \\]\n\n\\[ \\vdash \\Gamma_1; \\Delta_1 \\vdash P[y_1/y] \\rightarrow \\circ \\]\n\n\\[ \\Gamma_1 \\setminus y_1; \\Delta_1 \\setminus y_1 \\vdash \\lambda y_1.P[y_1/y] : C \\rightarrow \\circ \\]\n\nLet \\( \\tilde{x} = \\text{fv}(P) \\) and \\( \\Gamma_1 = \\Gamma \\setminus \\tilde{x} \\). Also, let \\( \\Theta_1 \\) be a balanced environment such that\n\n\\[ \\text{dom}(\\Theta_1) = \\{c_k, \\ldots, c_{k+|P|-1} \\} \\cup \\{c_{k+1}, \\ldots, c_{k+|P|-1} \\} \\]\n\nand \\( \\Theta_1(c_k) = M \\) with \\( M = (G(\\Gamma \\setminus y_1), G(\\Delta))(\\bar{x}) \\). Then, by IH (Part 1) on the first assumption of (69) we have:\n\n\\[ \\vdash \\Gamma_1; \\Theta_1 \\vdash \\lambda y_1.P[y_1/y] \\rightarrow \\circ \\]\n\nBy Def. 3.2 and Def. 3.4 and the second assumption of (69) we have:\n\n\\[ \\vdash \\Gamma; \\Theta_2 \\vdash \\bar{y} : G(C) \\]\n\nwhere \\( \\bar{y} = (y_1, \\ldots, y_{|G(\\Delta)|}) \\).\n\nWe define \\( \\Theta = \\Theta_1, \\bar{T} !!(\\bar{M}); \\text{ end.} \\) By Tab. 1, we have:\n\n\\[ \\forall^k (\\lambda y. P) = \\lambda \\bar{y} : G(C), \\bar{T} !!(\\bar{x}). \\text{O} \\mid B^k_2(P[y/y]) \\]\nBy construction Θ is balanced since Θ(c_k) dual θ(π_k) and Θ_1 is balanced. We use an auxiliary derivation:\n\n\\[\\begin{array}{c}\n\\text{Nil} \\\\\n\\text{End} \\quad G(\\Gamma); \\emptyset; 0 \\vdash 0 \\triangleright \\\\\n\\text{Send} \\quad G(\\Gamma); \\emptyset; c_k : \\text{end} \\vdash 0 \\triangleright \\\\\n& \\quad \\frac{\\text{PolyVar}}{G(\\Gamma); G(\\Lambda); \\emptyset \\vdash \\bar{x} \\triangleright M} \\\\\n& \\quad \\frac{G(\\Gamma); G(\\Lambda); \\bar{\\pi}_k \\downarrow (\\bar{M}); \\text{end} \\vdash \\bar{\\pi}_k! (\\bar{x}) \\triangleright}{}\n\\end{array}\\] \n\n(72)\n\nThe following tree proves this part:\n\n\\[\\begin{array}{c}\n\\text{Par} \\\\\n& \\quad \\frac{(\\text{Lem. } A.3) \\text{ with } \\bar{x}}{G(\\Gamma); G(\\Lambda); G(\\Delta_1), \\Theta_1 \\vdash B^k_\\nu (P\\{y/y\\}) \\triangleright}{}\n\\end{array}\\] \n\n(70)\n\n(73)\n\nThe following tree concludes this part (and the proof):\n\n\\[\\begin{array}{c}\n\\text{Abs} \\\\\n& \\quad \\frac{G(\\Gamma \\setminus y_1); G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash \\lambda \\bar{y} : G(C), \\bar{\\pi}_k! (\\bar{x}) \\triangleright 0 | B^k_\\nu (P\\{y/y\\}) \\triangleright}{}\n\\end{array}\\] \n\n(74)\n\nBy assumption, Γ; Λ; Δ ⊢ V ∧ C →. In this case Rule PROM can be applied:\n\n\\[\\begin{array}{c}\n\\text{Abs} \\\\\n& \\quad \\frac{\\Gamma; \\emptyset; \\Delta \\vdash P\\{y/y\\} \\triangleright}{}\n\\end{array}\\] \n\n(76)\n\n(75)\n\nLet \\( \\bar{x} = \\text{fv}(P) \\), Γ_1 = Γ \\setminus \\bar{x} \\), and let Θ_1 be defined as in Part 2. Then, by IH (Part 1) on the first assumption of Rule ABS in (75) we have:\n\n\\[G(\\Gamma_1); \\emptyset; G(\\Delta), \\Theta_1 \\vdash B^k_\\nu (P\\{y/y\\}) \\triangleright \\]\n\n(77)\n\nwhere \\( \\bar{y} = (y_1, \\ldots, y_{|G(C)|}) \\).\n\nLet Θ be defined as in Part 2. By Tab. 1 we have:\n\n\\[\\forall \\nu. (\\lambda y. P) = \\lambda \\bar{y} : G(C), (\\nu \\bar{c})\\bar{\\pi}_k! (\\bar{x}) \\triangleright 0 | B^k_\\nu (P\\{y/y\\}) \\]\n\n(79)\n\nwhere \\( \\bar{c} = (c_k, \\ldots, c_{k+|V|-1}) \\).\n\nWe use some auxiliary derivations:\n\n\\[\\begin{array}{c}\n\\text{Nil} \\\\\n\\text{End} \\quad G(\\Gamma); \\emptyset; 0 \\vdash 0 \\triangleright \\\\\n\\text{Send} \\quad G(\\Gamma); \\emptyset; c_k : \\text{end} \\vdash 0 \\triangleright \\\\\n& \\quad \\frac{\\text{PolyVar}}{G(\\Gamma); G(\\Lambda); \\emptyset \\vdash \\bar{x} \\triangleright M} \\\\\n& \\quad \\frac{G(\\Gamma); G(\\Lambda); \\bar{\\pi}_k \\downarrow (\\bar{M}); \\text{end} \\vdash \\bar{\\pi}_k! (\\bar{x}) \\triangleright}{}\n\\end{array}\\] \n\n(78)\n\n(70)\n\n(79)\n\nThe following tree concludes this part (and the proof):\n\n\\[\\begin{array}{c}\n\\text{Abs} \\\\\n& \\quad \\frac{G(\\Gamma \\setminus y_1); \\emptyset; \\emptyset \\vdash \\lambda \\bar{y} : G(C), (\\nu \\bar{c})\\bar{\\pi}_k! (\\bar{x}) \\triangleright 0 | B^k_\\nu (P\\{y/y\\}) \\triangleright}{}\n\\end{array}\\] \n\n(80)\nA.3 Proof of Thm. 3.11\n\nProof. By assumption, $\\Gamma; \\emptyset; \\Delta \\vdash P \\triangleright \\sigma$. Then, by applying Lem. A.2 we have:\n\n$$\\Gamma; \\emptyset; \\Delta \\vdash P \\triangleright \\sigma$$\n\nBy Def. 3.8, we shall prove the following judgment:\n\n$$G(\\Gamma); \\emptyset; G(\\Delta, \\Theta) \\triangleright (\\nu \\tilde{c})(\\tau_k; \\emptyset)| - \\ast \\vdash \\emptyset$$\n\nwhere $\\tilde{c} = (c_1, \\ldots, c_{k+1}|P|^{-1})$ and $k > 0$. Since $P$ is an initialized process, we apply Thm. 3.10 to (81) to get:\n\n$$G(\\Gamma); \\emptyset; G(\\Delta, \\Theta) \\triangleright B^k_{\\emptyset}(P)$$\n\nwhere $\\Theta$ is balanced with $\\text{dom}(\\Theta) = \\{c_k, c_{k+1}, \\ldots, c_{k+P|^{-1}}\\} \\cup \\{\\tau_k; \\emptyset| - \\ast\\}$ and $\\Theta(c_k) = ?(\\cdot)$. By assumption, $\\nu(P) = \\emptyset$.\n\nThe following tree concludes the proof:\n\n\\[\n\\begin{array}{c}\n\\text{Send} \\\n\\text{Par} \\\n\\text{PolyResS}\n\\end{array}\n\\]\n\n\\[\n\\frac{G(\\Gamma); \\emptyset; G(\\Delta, \\Theta) \\triangleright (\\nu \\tilde{c})(\\tau_k; \\emptyset)| - \\ast \\vdash \\emptyset \\quad \\text{by IH}}{G(\\Gamma); \\emptyset; G(\\Delta; \\emptyset; \\emptyset) \\triangleright B^k_{\\emptyset}(P) \\triangleright \\sigma}\n\\]\n\nRule PolyResS can be used: the environment obtained by extending $\\Theta$ with $\\tau_k; \\emptyset| - \\ast$ is balanced, and for each $c_j \\in \\tilde{c}$ such that $c_j : S$ there is a $\\tau_j : T$, with $S$ dual $T$. \n\nB Appendix to §3.3\n\nThm. 3.10 holds also for the extension with selection and branching. We now present the additional cases of the proof.\n\nProof (Extension of Thm. 3.10 with Selection/Branching). The proof is as before. We need to consider two additional cases for Part (1) of the theorem:\n\n1. Case $P = u_i \\triangleright \\{l_j : P_j\\}_{j \\in I}$. For this case Rule BRA can be applied:\n\n$$\\begin{array}{c}\n\\forall j \\in I \\\n\\text{BRA}\n\\end{array}\n\\]\n\nLet $\\tilde{x} = \\nu(P)$ and $\\tilde{x}_j = \\nu(P_j)$ for all $j \\in I$. Notice that $\\tilde{x}_j \\subseteq \\tilde{x}$, for all $j \\in I$. Also, $\\Gamma_{j,1} = \\Gamma \\setminus \\tilde{x}_j$ and let $\\Theta_j$ be a balanced environment such that $\\text{dom}(\\Theta_j) = \\{c_{k+1}, \\ldots, c_{k+P|^{-1}}\\} \\cup \\{\\tilde{x}_j, \\ldots, \\tilde{x}_j\\}$, $\\Theta_j(c_{k+1}) = ?(\\tilde{M}_j)$; $\\text{end}$ with $\\tilde{M}_j = (G(\\Gamma), G(\\Lambda))(\\tilde{x}_j)$. Then, by IH on the assumption of (85) we have for all $j \\in I$:\n\n$$G(\\Gamma \\setminus \\tilde{x}_j); \\emptyset; G(\\Delta, u_i : S_j), \\Theta_j \\triangleright B^{k+1}_{\\emptyset}(P_j)$$\n\nWe define $\\Theta = c_k : \\!(\\tilde{M}); \\text{end}$ with $(G(\\Gamma), G(\\Lambda))(\\tilde{x}) = \\tilde{M}$. By construction, $\\Theta$ is balanced.\n\nBy Def. 3.14, $|P| = 1$ and so $\\text{dom}(\\Theta) = \\{c_k\\}$. Let $y^i_j = (y^1_j, \\ldots, y^P_{\\text{dom}(S_j)}).$ By the function defined in Tab. 3 we have:\n\n$$B^{k}_{\\emptyset}(u_i \\triangleright \\{l_j : P_j\\}_{j \\in I}) = c_k ?(\\tilde{x}).u_i \\triangleright \\{l_j : u_i ! (N_{u,i} \\cdot 0\\}_{j \\in I}$$\nwhere $N_{u,j} = \\lambda \\tilde{y} y_j : G(S_j). (\\nu \\tilde{c}_j)(c_{k+1}[\\tilde{x}]_0 | B_{\\tilde{x}}^{k+1}(P_j[y_j^u/u_i]))$ and $\\tilde{c}_j = (c_{k+1}, \\ldots, c_{k+|P_j|})$.\n\nLet $\\Gamma_1 = \\Gamma \\setminus \\tilde{x}$. We shall prove the following judgment:\n\n$$G(\\Gamma_1); \\emptyset; G(\\Delta, u_i : & \\{l_j : S_j\\}_{j \\in I}), \\Theta \\vdash B_{\\tilde{x}}^{k+1}(P_j[y_j^u/u_i]) \\triangleright \\triangleright 0$$\n\nWe shall prove the following judgment:\n\n$$G(\\Gamma_1); \\emptyset; G(\\Delta, u_i : & \\{l_j : S_j\\}_{j \\in I}), \\Theta \\vdash B_{\\tilde{x}}^{k+1}(P_j[y_j^u/u_i]) \\triangleright \\triangleright 0$$\n\nWe define $\\Theta_{j,1} = \\Theta_j, c_{k+1} : !M$; $\\texttt{end}$. We use some auxiliary derivations for all $j \\in I$:\n\n\\[\n\\begin{align*}\n\\text{PolyAbs} & \\quad \\frac{G(\\Gamma); \\emptyset; \\overline{y}_j : G(S_j)}{G(\\Gamma); \\emptyset; \\nu \\overline{c}_j : G(S_j), (\\nu \\overline{c}_j)(c_{k+1}[\\tilde{x}]_0 | B_{\\tilde{x}}^{k+1}(P_j[y_j^u/u_i])) \\triangleright \\triangleright 0} \\\\\n\\text{PolySess} & \\quad \\frac{\\text{Nil}}{G(\\Gamma); \\emptyset; \\emptyset \\triangleright \\emptyset} \\\\\n\\text{End} & \\quad \\frac{G(\\Gamma); \\emptyset; \\emptyset \\triangleright \\emptyset}{G(\\Gamma); \\emptyset; \\Gamma \\triangleright \\emptyset} \\\\\n\\text{PolySend} & \\quad \\frac{G(\\Gamma); \\emptyset; \\Gamma \\triangleright \\emptyset}{G(\\Gamma); \\emptyset; \\bar{c}_{k+1} \\triangleright \\emptyset} \\\\\n\\text{PolyRes} & \\quad \\frac{G(\\Gamma); \\emptyset; \\Gamma \\triangleright \\emptyset}{G(\\Gamma); \\emptyset; \\Theta_{j,1} \\triangleright \\emptyset} \\\\\n\\text{PolyVar} & \\quad \\frac{G(\\Gamma); \\emptyset; \\Theta_{j,1} \\triangleright \\emptyset}{G(\\Gamma); \\emptyset; \\emptyset \\triangleright \\emptyset} \\\\\n\\text{Par} & \\quad \\frac{(\\text{Lem. A.2}) \\text{ with } \\sigma}{G(\\Gamma) \\setminus \\tilde{x}; \\emptyset; G(\\Delta, \\tilde{y}_j y_j : G(S_j)) \\triangleright \\triangleright 0} \\\\\n& \\quad \\frac{(\\text{Lem. A.3}) \\text{ with } \\tilde{x}_j}{G(\\Gamma) \\setminus \\tilde{x}_j; \\emptyset; G(\\Delta, \\tilde{y}_j y_j : G(S_j)) \\triangleright \\triangleright 0} \\\\\n\\end{align*}\n\\]\n\nwhere $\\sigma = \\{\\tilde{y}_j / \\tilde{u}\\}$ with $\\tilde{u} = (u_1, \\ldots, u_{i+|G(S_j)|})$.\n\nHere we may notice that by Def. 3.4 and Def. 3.13 we have:\n\n$$G(u_i : & \\{l_j : S_j\\}_{j \\in I}) = u_i : & \\{l_i : !(G(S_j) \\rightarrow \\triangleright 0)\\}_{j \\in I}$$\n\nThe following tree proves this case:\n\n$$\\begin{array}{c}\n\\text{PolyRec} \\quad \\frac{G(\\Gamma_1); \\emptyset; \\Theta_{j,1} \\triangleright \\emptyset}{G(\\Gamma_1); \\emptyset; \\emptyset \\triangleright \\emptyset} \\\\\n\\text{Par} \\quad \\frac{G(\\Gamma); \\emptyset; \\emptyset \\triangleright \\emptyset}{G(\\Gamma); \\emptyset; \\emptyset \\triangleright \\emptyset} \\\\\n\\text{End} \\quad \\frac{G(\\Gamma); \\emptyset; \\emptyset \\triangleright \\emptyset}{G(\\Gamma); \\emptyset; \\emptyset \\triangleright \\emptyset} \\\\\n\\text{PolyVar} \\quad \\frac{G(\\Gamma, u_i : & \\{l_j : S_j\\}_{j \\in I}) \\triangleright \\emptyset}{G(\\Gamma, u_i : & \\{l_j : S_j\\}_{j \\in I}) \\triangleright \\emptyset} \\\\\n\\end{array}$$\n2. Case $P = u_i \\circ l_j.P'$. For this case Rule Sel can be applied:\n\n\\[\n\\begin{align*}\n\\text{Sel} & \\quad \\Gamma; \\Delta, u_i : S_j \\vdash P' \\triangleright \\triangleright \\quad j \\in I \\\\\n& \\quad \\Gamma; \\Delta, u_i : (\\{l_j : S_j\\})_{j \\in I} \\vdash u_i \\circ l_j.P' \\triangleright \\triangleright\n\\end{align*}\n\\]\n\n(92)\n\nLet $\\bar{x} = \\text{fv}(P')$ and $\\Gamma_1 = \\Gamma \\setminus \\bar{x}$. Also, let $\\Theta_1$ be a balanced environment such that $\\text{dom}(\\Theta_1) = \\{c_{k+1}, \\ldots, c_{k+|P'|} \\} \\cup \\{\\bar{r}_{k+1}, \\ldots, \\bar{r}_{k+|P'|}\\}$ and $\\Theta_1(c_{k+2}) = (?M); \\text{end}$ where $M = (G(\\Gamma), G(\\Lambda))(\\bar{x})$. Then, by IH on the first assumption of (92) we have:\n\n\\[\nG(\\Gamma_1); \\emptyset; G(\\Delta, u_i : S_j), \\Theta_1 \\vdash B_{k+2}^i(P') \\triangleright \\triangleright\n\\]\n\n(93)\n\nWe define $\\Theta = \\Theta_1, \\Theta'$ where:\n\n\\[\n\\Theta' = c_k : (?M); \\text{end}, c_{k+1} : (?G(\\bar{S}_j) \\triangleright \\triangleright); \\text{end}, r_{k+1} : !G(\\bar{S}_j) \\triangleright \\triangleright); \\text{end}, r_{k+2} : !(!M); \\text{end}\n\\]\n\nBy Def. 3.14, $|P| = |P'| + 2$, so\n\n\\[\n\\text{dom}(\\Theta) = \\{c_k, c_{k+1}, \\ldots, c_{k+|P'|-1}\\} \\cup \\{\\bar{r}_{k+1}, \\ldots, \\bar{r}_{k+|P'|-1}\\}\n\\]\n\nBy construction $\\Theta$ is balanced since $\\Theta(c_{k+2})$ dual $\\Theta(r_{k+2})$ and $\\Theta_1$ and $\\Theta'$ are balanced.\n\nLet $\\bar{y} = (y_1, \\ldots, y_{|G(\\bar{S}_j)|})$. By Tab. 3:\n\n\\[\nB_{k+2}^i(u_i \\circ l_j.P') = c_k.(\\bar{x}), \\bar{r}_{k+1} \\triangleright \\triangleright (\\lambda \\bar{y}. u_i \\circ l_j.u_i.(\\bar{x}), \\bar{r}_{k+2} \\triangleright \\triangleright (\\bar{y}). \\bar{y}) |(\\nu \\bar{u} : G(\\bar{S}_j))(c_{k+1}.(\\bar{y}), \\bar{y} \\bar{y} / B_{k+2}^i(P' \\cup \\{u_i\\}))\n\\]\n\nwhere $\\bar{u} = (u_1, \\ldots, u_{|G(\\bar{S}_j)|})$ and $\\bar{u} = (u_1, \\ldots, u_{|G(\\bar{S}_j)|})$. We shall prove the following judgment:\n\n\\[\nG(\\Gamma); \\emptyset; G(\\Delta, u_i : (\\{l_j : S_j\\})_{j \\in I}), \\Theta \\vdash B_{k+2}^i(u_i \\circ l_j.P') \\triangleright \\triangleright\n\\]\n\nFor this, we will use the following auxiliary derivations for the left-hand side component:\n\n\\[\n\\begin{align*}\n\\text{IVar} & \\quad G(\\Gamma); z : G(\\bar{S}_j) \\triangleright \\triangleright ; \\emptyset \\vdash z \\triangleright G(\\bar{S}_j) ; \\emptyset \\triangleright \\triangleright \\\\\n\\text{PolyApp} & \\quad G(\\Gamma); z : G(\\bar{S}_j) \\triangleright \\triangleright ; \\bar{y} : G(\\bar{S}_j) \\vdash z \\bar{y} \\triangleright \\triangleright \\\\\n& \\quad \\text{End} \\quad G(\\Gamma); z : G(\\bar{S}_j) \\triangleright \\triangleright ; \\bar{y} : G(\\bar{S}_j), \\bar{r}_{k+1} : \\text{end} \\vdash z \\bar{y} \\triangleright \\triangleright \\\\\n& \\quad \\text{End} \\quad G(\\Gamma); \\emptyset; G(\\Delta); \\emptyset \\vdash \\bar{x} \\triangleright \\triangleright M \\\\\n& \\quad G(\\Gamma); G(\\Lambda), z : G(\\bar{S}_j) \\triangleright \\triangleright ; \\bar{y} : G(\\bar{S}_j), \\bar{r}_{k+2} : !(!M); \\text{end} \\vdash \\bar{r}_{k+2}!(\\bar{x}), \\bar{y} \\bar{y} \\triangleright \\triangleright \\\\\n& \\quad \\text{End} \\quad G(\\Gamma); G(\\Lambda), z : G(\\bar{S}_j) \\triangleright \\triangleright ; \\bar{y} : G(\\bar{S}_j), \\bar{r}_{k+2} : !(!M); \\text{end}, u_i : \\text{end} \\vdash u_i \\bar{r}_{k+2}!(\\bar{x}), \\bar{y} \\bar{y} \\triangleright \\triangleright \\\\\n& \\quad \\text{Rev} \\quad G(\\Gamma); G(\\Lambda); u_i : (?G(\\bar{S}_j) \\triangleright \\triangleright) ; \\text{end} \\vdash \\bar{y} : G(\\bar{S}_j), \\bar{r}_{k+2} : !(!M); \\text{end} \\vdash u_i ?(\\bar{x}), \\bar{r}_{k+2}!(\\bar{x}), \\bar{y} \\bar{y} \\triangleright \\triangleright \\\\\n& \\quad \\text{Sel} \\quad G(\\Gamma); G(\\Lambda); u_i : (\\{?G(\\bar{S}_j) \\triangleright \\triangleright\\}) ; \\text{end} \\vdash \\bar{y} : G(\\bar{S}_j), \\bar{r}_{k+2} : !(!M); \\text{end} \\vdash u_i \\circ l_j, u_i ?(\\bar{x}), \\bar{r}_{k+2}!(\\bar{x}), \\bar{y} \\bar{y} \\triangleright \\triangleright\n\\end{align*}\n\\]\n\n(94) (95) (96)\nWe use the following auxiliary lemma:\n\n**Lemma C.1.**\n\n\\[\n\\sigma \\triangleright R_{\\text{cv}} \\triangleright \\text{PolyRcv} \\triangleright L_{\\text{Var}} \\triangleright (\\Gamma, \\Theta) \\vdash \\lambda x.y \\triangleleft l_j, u_i \\triangleleft ?(z).z \\triangleright G(S_j) \\rightarrow \\circ \\circ\n\\]\n\nThe following auxiliary derivations are used to type the right-hand side component:\n\n\\[\n\\begin{align*}\n\\text{Abs} & \\quad \\text{PolyVar} \\quad \\frac{\\text{(96)}}{\\text{PolyVar}} \\quad (\\Gamma); \\emptyset; \\tilde{y} : G(S_j) \\vdash \\tilde{y} \\triangleright G(S_j) \\\\\n\\text{Send} & \\quad \\text{End} \\quad \\frac{\\text{Nil}}{\\text{G(\\Gamma); \\emptyset; u_i : \\text{end} \\vdash 0}} (\\text{97}) \\\\\n\\text{End} & \\quad \\text{PolyVar} \\quad \\frac{\\text{G(\\Gamma); G(\\Lambda); u_i : \\text{end} \\vdash \\circ}}{\\text{G(\\Gamma); G(\\Lambda); u_i : \\text{end} \\vdash \\circ \\triangleright M}} (\\text{98}) \\\\\n\\text{PolyVar} & \\quad \\text{G(\\Gamma); G(\\Lambda); \\emptyset \\vdash \\tilde{x} \\triangleright M} (\\text{99})\n\\end{align*}\n\\]\n\n\\[\n\\begin{align*}\n\\text{LVar} & \\quad \\text{PolyVar} \\quad \\frac{\\text{G(\\Gamma); y : G(S_j) \\rightarrow \\circ; \\emptyset \\vdash y \\triangleright G(S_j) \\rightarrow \\circ}}{\\text{G(\\Gamma); y : G(S_j) \\rightarrow \\circ; \\tilde{y} : G(S_j) \\vdash y \\tilde{y} \\triangleright \\circ}} (\\text{100}) \\\\\n\\text{App} & \\quad \\text{PolyResS} \\quad \\frac{\\text{G(\\Gamma)}; \\emptyset: \\text{\\tilde{y} : G(S_j) \\rightarrow \\circ \\triangleright \\circ}}{\\text{G(\\Gamma); y : G(S_j) \\rightarrow \\circ; \\emptyset \\vdash y \\triangleright G(S_j) \\rightarrow \\circ}} (\\text{101})\n\\end{align*}\n\\]\n\n\\[\n\\begin{align*}\n\\text{Recv} & \\quad \\text{Par} \\quad \\frac{\\text{G(\\Gamma); \\emptyset: c_{k+1} \\rightarrow (y : G(S_j) \\rightarrow \\circ); \\text{end} \\vdash c_{k+1}\\triangleright (y : G(S_j) \\rightarrow \\circ; y \\tilde{y} \\triangleright \\circ)}}{\\text{G(\\Gamma); \\emptyset: c_{k+1} \\rightarrow (y : G(S_j) \\rightarrow \\circ); \\text{end} \\vdash c_{k+1} \\rightarrow (y : G(S_j) \\rightarrow \\circ; y \\tilde{y} \\triangleright \\circ) \\triangleright \\circ}} (\\text{102})\n\\end{align*}\n\\]\n\n\\[\n\\begin{align*}\n\\text{LVar} & \\quad \\text{Par} \\quad \\frac{\\text{G(\\Gamma); \\emptyset: G(\\Delta, u_{i+1} : S_j) \\rightarrow \\circ; c_{k+1} \\rightarrow (y : G(S_j) \\rightarrow \\circ); \\text{end} \\vdash c_{k+1}\\triangleright (y : G(S_j) \\rightarrow \\circ; y \\tilde{y} \\triangleright \\circ) \\triangleright \\circ}}{\\text{G(\\Gamma); \\emptyset: G(\\Delta, u_{i+1} : S_j) \\rightarrow \\circ; c_{k+1} \\rightarrow (y : G(S_j) \\rightarrow \\circ); \\text{end} \\vdash c_{k+1}\\triangleright (y : G(S_j) \\rightarrow \\circ; y \\tilde{y} \\triangleright \\circ) \\triangleright \\circ) \\triangleright \\circ}} (\\text{103})\n\\end{align*}\n\\]\n\nwhere \\( \\sigma = \\{ \\tilde{y}/\\tilde{n} \\} \\) with \\( \\tilde{n} = (u_i, \\ldots, u_{i+1}[G(S_j)_i]) \\). The following tree proves this case:\n\n\\[\n\\begin{align*}\n\\text{Par} & \\quad \\text{Par} \\quad \\frac{\\text{G(\\Gamma); \\emptyset: G(\\Delta, u_{i+1} : \\Sigma_{j \\in I} l_j : S_j) \\rightarrow \\circ; \\Theta \\vdash B^{k+2}_{p}(u_{i+1}) \\triangleright \\circ \\triangleright \\circ}}{\\text{G(\\Gamma); \\emptyset: G(\\Delta, u_{i+1} : \\Sigma_{j \\in I} l_j : S_j) \\rightarrow \\circ; \\Theta \\vdash B^{k+2}_{p}(u_{i+1}) \\triangleright \\circ \\triangleright \\circ)} (\\text{104})\n\\end{align*}\n\\]\n\n\\[\\)\n\n\\[\\]\nC.1 Proof of Thm. 3.27\n\nProof. By mutual induction on the structure of $P$ and $V$. Here, we analyze only Part (1) of the theorem, as Part (2) and Part (3) are proven similarly:\n\n1. By assumption $\\Gamma; \\Delta, \\Delta_\\mu \\vdash P \\triangleright \\circ$. There are four cases, depending on the shape of $P$. We consider two representative cases. We omit other cases as they are similar.\n\n a. Case $P = r!\\langle V \\rangle.P'$, when $V$ is not a variable. We consider case: $r : S \\in \\Delta_\\mu$. For this case Rule SEND can be applied:\n\n $$\\frac{\\Gamma; A_1; \\Delta_1, \\Delta_\\mu_1 \\vdash P' \\triangleright \\circ \\quad \\Gamma; A_2; \\Delta_2, \\Delta_\\mu_2 \\vdash V \\triangleright U}{\\Gamma; A_1, A_2; \\Delta_1, \\Delta_2, ((\\Delta_\\mu_1, \\Delta_\\mu_2) \\setminus \\{r : S\\}), \\Gamma; P \\triangleright \\langle U \\rangle, S \\vdash r!\\langle V \\rangle.P' \\triangleright \\circ}$$\n\n (103)\n\n Let $\\tilde{w} = \\text{fv}(P')$ and $l = |V|$. Let $\\Theta_1$, $\\Theta_2$, $\\Theta'$ and $\\Theta$ be defined as in the corresponding case of Thm. 3.10 proof. Also, let $\\Gamma'_1 = \\Gamma \\setminus \\tilde{w}$. We define:\n\n $$\\Phi_i = \\prod_{r \\in \\text{dom}(\\Delta_\\mu_i)} c^r : (\\Delta_\\mu_i(r) \\rightarrow \\circ) \\text{ for } i \\in \\{1, 2\\}$$\n\n (104)\n\n Then, by IH on the first assumption of (103) we have:\n\n $$\\mathcal{G}(\\Gamma'_1), \\Phi_1; \\emptyset; \\mathcal{G}(\\Delta_1), \\Theta_1 \\vdash B^k_{\\tilde{w}}(P') \\triangleright \\circ$$\n\n (105)\n\n Let $\\Gamma'_2 = \\Gamma \\setminus \\tilde{y}$. Then, by IH (Part 2) on the second assumption of (103) we have:\n\n $$\\mathcal{G}(\\Gamma'_2), \\Phi_2; \\mathcal{G}(\\Delta_2), \\Theta_2 \\vdash V^{k+1}_{\\tilde{y}}(V) \\triangleright \\mathcal{G}(U)$$\n\n (106)\n\n By Tab. 4 we have:\n\n $$B^k_{\\tilde{w}}(P) = c_k(\\tilde{x}), c^{r!\\langle N_V \\rangle} \\cdot B^{k+1}_{\\tilde{w}}(P')$$\n\n where $N_V = \\lambda \\tilde{z}. z_{f(S)}!(\\langle \\tilde{y} \\rangle^{k+1}(V)), \\tilde{z} ? (b). (b \\tilde{z})$\n\n We notice that $r \\in \\text{rn}(V), \\text{rn}(P)$ since $r$ has recursive type $S$. Hence, by (104) we know $(\\Phi_1, \\Phi_2)(c^r) = (\\mathcal{R}^*(S) \\rightarrow \\circ)$. Further, we know that $S = !\\langle U \\rangle, S'$ and by Def. 3.18, $\\mathcal{R}^*(S) = \\mathcal{R}^*(S')$. So we define $\\Phi = \\Phi_1, \\Phi_2$. Let $\\Gamma_1 = \\Gamma \\setminus \\tilde{x}$ where $\\tilde{x} = \\text{fv}(P)$. We shall prove the following judgment:\n\n $$\\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset; \\mathcal{G}(\\Delta_1, \\Delta_2), \\Theta \\vdash B^k_{\\tilde{x}}(r!\\langle V \\rangle.P') \\triangleright \\circ$$\n\n We use auxiliary derivations:\n\n $$\\begin{array}{ccc}\n \\text{PolyApp} & \\frac{\\mathcal{G}(\\Gamma_1), \\Phi; b : \\mathcal{R}^*(S) \\rightarrow \\circ; \\emptyset \\vdash \\mathcal{G}(\\Gamma_1), \\Phi; \\tilde{z} : \\mathcal{R}^*(S) \\vdash \\tilde{z} \\triangleright \\mathcal{R}^*(S)}{\\mathcal{G}(\\Gamma_1), \\Phi; b : \\mathcal{R}^*(S) \\rightarrow \\circ; \\tilde{z} \\triangleright \\mathcal{R}^*(S) \\vdash b \\tilde{z} \\triangleright \\circ} \\\\\n \\text{LVar} & \\frac{\\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset \\vdash c^r \\triangleright \\mathcal{R}^*(S) \\rightarrow \\circ; \\emptyset \\vdash \\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset, \\tilde{z} : \\mathcal{R}^*(S) \\vdash \\tilde{z} ? (b). (b \\tilde{z}) \\triangleright \\circ}{\\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset, \\tilde{z} : \\mathcal{R}^*(S) \\vdash c^r ? (b). (b \\tilde{z}) \\triangleright \\circ} \\\\\n \\text{PolySess} & \\frac{\\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset \\vdash b \\triangleright \\mathcal{R}^*(S) \\rightarrow \\circ; \\emptyset \\vdash \\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset, \\tilde{z} : \\mathcal{R}^*(S) \\vdash \\tilde{z} ? (b). (b \\tilde{z}) \\triangleright \\circ}{\\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset \\vdash c^r \\triangleright \\mathcal{R}^*(S) \\rightarrow \\circ; \\emptyset \\vdash \\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset, \\tilde{z} : \\mathcal{R}^*(S) \\vdash \\tilde{z} ? (b). (b \\tilde{z}) \\triangleright \\circ} \\\\\n \\text{Sh} & \\frac{\\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset \\vdash \\tilde{z} ? (b). (b \\tilde{z}) \\triangleright \\circ}{\\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset \\vdash c^r \\triangleright \\mathcal{R}^*(S) \\rightarrow \\circ; \\emptyset \\vdash \\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset, \\tilde{z} : \\mathcal{R}^*(S) \\vdash \\tilde{z} ? (b). (b \\tilde{z}) \\triangleright \\circ}\n \\end{array}$$\n\n (107)\n\n (108)\n11:46 Minimal Session Types\n\n---\n\n\\[ \\text{PolySend} \\]\n\n\\[\n\\frac{\\text{PolyVar}}{\\exists \\bar{w} \\vdash \\bar{M}_1} \\quad \\text{(108)}\n\\]\n\n\\[\n\\frac{\\text{Send}}{G(\\Gamma), \\Phi; G(\\Lambda_1); \\Theta'; \\bar{z} : \\mathcal{R}^*(S) \\vdash \\bar{c}' \\langle \\mathcal{R}^*(S) \\rangle \\circ \\bar{c} \\triangleright} \\quad \\text{(109)}\n\\]\n\n(Lem. A.3) with \\( \\Phi \\)\n\n(Lem. A.3) with \\( \\bar{z} \\)\n\n\\[\n\\frac{\\text{Send}}{G(\\Gamma), \\Phi; G(\\Lambda_1); \\Theta_2 ; \\Theta' \\vdash \\mathcal{R}^*(S) \\circ \\circ} \\quad \\text{(110)}\n\\]\n\nBy Lem. C.1 we know that if \\( \\bar{z} : \\mathcal{R}^*(S) \\) then \\( z_f(S) : \\mu \\cdot (G(U)); t. \\)\n\n---\n\n\\[ \\text{PolyAbs} \\]\n\n\\[\n\\frac{\\text{PolySess}}{\\exists \\bar{w} \\vdash \\bar{M}_1} \\quad \\text{(109)}\n\\]\n\n\\[\n\\frac{\\text{Receive}}{G(\\Gamma), \\Phi; \\emptyset ; \\emptyset \\vdash \\bar{c}' \\langle \\mathcal{R}^*(S) \\rangle \\circ \\circ} \\quad \\text{(111)}\n\\]\n\n(Lem. A.3) with \\( \\Phi \\)\n\n(Lem. A.3) with \\( \\bar{z} \\)\n\n\\[\n\\frac{\\text{Receive}}{G(\\Gamma), \\Phi; \\emptyset ; \\emptyset \\vdash \\bar{c} \\triangleright} \\quad \\text{(112)}\n\\]\n\n\\[ \\text{PolyVar} \\]\n\n\\[\n\\frac{\\text{Send}}{G(\\Gamma), \\Phi; G(\\Lambda_1, \\Lambda_2); \\Theta_2 ; \\Theta' \\vdash \\mathcal{R}^*(S) \\circ \\circ} \\quad \\text{(113)}\n\\]\n\nThe following tree proves this case:\n\n(Lem. A.3) with \\( \\Phi_2 \\)\n\n(Lem. A.4) with \\( \\bar{y} \\)\n\n\\[\n\\frac{\\text{Receive}}{G(\\Gamma), \\Phi; \\emptyset ; \\emptyset \\vdash \\bar{c} \\triangleright} \\quad \\text{(114)}\n\\]\n\nb. Case \\( P = V (\\bar{r}, u_i) \\). We assume a certain order in the tuple \\((\\bar{r}, u_i)\\): names in \\( \\bar{r} \\) have recursive session types \\( \\bar{r} = (r_1, \\ldots, r_n) : (S_1, \\ldots, S_n) \\), and \\( u_i \\) has non-recursive session type \\( u_i : C \\). We distinguish two sub-cases: (i) \\( V : \\hat{S}C \\circ \\circ \\) and (ii) \\( V : \\hat{S}C \\circ \\circ \\). We will consider only sub-case (i) since the other is similar. For this case Rule \\textsc{PolyApp} can be applied:\n\n\\[\n\\frac{\\text{Receive}}{G(\\Gamma), \\Phi; \\emptyset ; \\emptyset \\vdash \\bar{c} \\triangleright} \\quad \\text{(115)}\n\\]\n\nLet \\( \\bar{x} = \\bar{f}V \\) and \\( \\Gamma_1 \\setminus \\bar{x} \\). Let \\( \\bar{x} = \\bar{f}V \\) and let \\( \\Theta_1 \\) be a balanced environment such that\n\n\\[\n\\text{dom}(\\Theta_1) = \\{c_{k+1}, \\ldots, c_{k+|V|}\\} \\cup \\{\\bar{r}_{k+1}, \\ldots, \\bar{r}_{k+|V|}\\}\n\\]\n\nand \\( \\Theta_1(c_{k+1}) = \\gamma(\\bar{M}); \\text{end} \\) and \\( \\Theta_1(\\bar{r}_{k+1} : c_{k+1}) = \\gamma(\\bar{M}); \\text{end} \\) where \\( \\bar{M} = (G(\\Gamma), G(\\Lambda))(\\bar{x}) \\).\n\nWe define:\n\n\\[\n\\Phi_1 = \\prod_{r \\in \\text{dom}(\\Delta_{n_1})} c' : \\langle \\mathcal{R}^\\circ(\\Delta_{n_1}(r)) \\circ \\circ \\rangle\n\\]\n\n---\n\n---\nThen, by IH (Part 2) on the first assumption of (115) we have:\n\n\\[ G(\\Gamma_1), \\Phi_1; \\emptyset; G(\\Delta_1), \\Theta_1 \\vdash \\gamma^k_{\\emptyset} V \\vdash G(SC) \\imp \\emptyset \\] \n\n(117)\n\nBy Def. 3.4 and Def. 3.18 and the second assumption of (115) we have:\n\n\\[ G(\\Gamma); \\emptyset; G(\\Delta_2), G(\\Delta_{\\mu_2}) \\vdash (\\vec{r}_1, \\ldots, \\vec{r}_n, \\vec{m}) : G(SC) \\]\n\n(118)\n\nwhere \\( \\vec{r}_i = (r_i^1, \\ldots, r_i^{1+|G(S)|-1}) \\) for \\( i \\in \\{1, \\ldots, n\\} \\) and \\( \\vec{m} = (u_i, \\ldots, u_i+|G(C)|-1) \\).\n\nWe define \\( \\Phi = \\Phi_1, \\Phi_2 \\) where:\n\n\\[ \\Phi_2 = \\prod_{r \\in \\text{dom}(\\Delta_{\\mu_2})} c^r : (\\mathcal{R}^s(\\Delta_{\\mu_2}(r)) \\imp \\emptyset) \\]\n\nWe define \\( \\Theta = \\Theta_1, c_k : ?(\\vec{M}) \\); end.\n\nWe will first consider the case where \\( n = 3 \\); the proof is then generalized for any \\( n \\geq 1 \\):\n\n- If \\( n = 3 \\) then \\( P = V (r_1, r_2, r_3, u_1) \\). By Tab. 4 we have:\n\n\\[ B^k_{\\emptyset} (V (r_1, r_2, r_3, u_1)) = c_{\\emptyset} (?x) e^{r_1!}(\\lambda x_1, e^{r_2!}(\\lambda x_2, e^{r_3!}(\\lambda x_3, Q), 0), 0, 0) \\]\n\nwhere \\( Q = \\gamma^k_{\\emptyset} V (\\vec{z}_1, \\ldots, \\vec{z}_n, \\vec{m}) \\); \\( \\vec{z}_i = (z_i^1, \\ldots, z_i^{1+|G(S)|-1}) \\) for \\( i \\in \\{1, 2, 3\\} \\); \\( \\vec{m} = (u_1, \\ldots, u_1+|G(C)|-1) \\).\n\nWe shall prove the following judgment:\n\n\\[ G(\\Gamma), \\Phi; \\emptyset; G(\\Delta_1, \\Delta_2), \\Theta \\vdash B^k_{\\emptyset} (V (\\vec{r}, u_1)) \\imp \\emptyset \\] \n\n(119)\n\nWe use auxiliary derivations:\n\n(Lem. A.3) with \\( \\Phi_2 \\)\n\n\\[ \\frac{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1), \\Theta_1 \\vdash \\gamma^k_{\\emptyset} V \\vdash G(SC) \\imp \\emptyset}{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash (\\vec{z}_1, \\vec{z}_2, \\vec{z}_3, \\vec{m}) \\vdash G(SC)} \\]\n\n(120)\n\n(Lem. A.2) with \\( \\sigma \\)\n\n\\[ \\frac{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1, G(\\Delta_{\\mu_2}) \\vdash \\gamma^k_{\\emptyset} V (\\vec{z}_1, \\vec{z}_2, \\vec{z}_3, \\vec{m})}{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash (\\vec{z}_1, \\vec{z}_2, \\vec{z}_3, \\vec{m}) \\vdash G(SC)} \\]\n\n(121)\n\nPolyApp\n\n\\[ \\frac{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash (\\vec{z}_1, \\vec{z}_2, \\vec{z}_3, \\vec{m})}{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash \\gamma^k_{\\emptyset} V \\vdash G(SC)} \\]\n\n(122)\n\nwhere \\( \\sigma = \\{\\vec{n}_1/\\vec{z}_1\\} \\cdot \\{\\vec{n}_2/\\vec{z}_2\\} \\cdot \\{\\vec{n}_3/\\vec{z}_3\\} \\) with \\( \\vec{n}_i = (r_i^1, \\ldots, r_i^{1+|G(S)|-1}) \\) for \\( i \\in \\{1, 2, 3\\} \\).\n\nPolyAbs\n\n\\[ \\frac{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash (\\vec{z}_1, \\vec{z}_2, \\vec{z}_3, \\vec{m})}{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash \\gamma^k_{\\emptyset} V \\vdash G(SC) \\imp \\emptyset} \\]\n\n(123)\n\nReq\n\n\\[ \\frac{\\text{Nil}}{G(\\Gamma), \\Phi; \\emptyset \\vdash \\emptyset} \\]\n\n(123)\n\nPolyAbs\n\n\\[ \\frac{G(\\Gamma), \\Phi; \\emptyset; \\emptyset \\vdash \\emptyset}{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash (\\vec{z}_1, \\vec{z}_2, \\vec{z}_3, \\vec{m}) \\vdash G(SC) \\imp \\emptyset} \\]\n\n(124)\n\nPolyAbs\n\n\\[ \\frac{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash (\\vec{z}_1, \\vec{z}_2, \\vec{z}_3, \\vec{m}) \\vdash G(SC) \\imp \\emptyset}{G(\\Gamma), \\Phi; G(\\Lambda); G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash (\\vec{z}_1, \\vec{z}_2, \\vec{z}_3, \\vec{m}) \\vdash G(SC) \\imp \\emptyset} \\]\n\n(125)\n11:48 Minimal Session Types\n\nWe construct auxiliary derivations parametrized by $\\sigma$\n\nWe shall prove the following judgment:\n\n$$\\sigma\\vdash Q$$\n\nBy Tab. 4 we have:\n\n$$\\begin{align*}\n\\text{PolyAbs} & \\quad \\frac{Q}{\\frac{\\text{PolyRcv}}{G(\\Gamma), \\Phi; G(\\Delta_1 \\Delta_2), \\Theta_1 \\vdash c^{e_2}! (\\lambda \\hat{z}_1. c^{e_3}! (\\lambda \\hat{z}_2. \\tilde{Q}.0), 0) \\triangleright G(S_1) \\rightarrow \\sigma}}{G(\\Gamma), \\Phi; \\tilde{z}_1 : G(S_1) \\vdash c^{e_2}! (\\lambda \\hat{z}_2. \\tilde{Q}.0), 0 \\triangleright G(S_1) \\rightarrow \\sigma} \\\\\n\\end{align*}$$\n\n(127)\n\nThe following tree proves this case:\n\n$$\\begin{align*}\n\\text{PolyRec} & \\quad \\frac{\\text{PolyVar}}{\\frac{\\text{LVar}}{G(\\Gamma_1), \\Phi; \\tilde{y} \\vdash \\tilde{x} \\triangleright \\tilde{M}}{G(\\Gamma_1), \\Phi; \\Phi; G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash B^k_{\\tilde{x}}(V(\\tilde{r}, u_i)) \\triangleright \\sigma}}{G(\\Gamma), \\Phi; G(\\Delta_1 \\Delta_2), \\Theta_1 \\vdash B^k_{\\tilde{x}}(V(\\tilde{r}, u_i)) \\triangleright \\sigma} \\\\\n\\end{align*}$$\n\n(128)\n\nNow we consider the general case for any $n \\geq 1$:\n\nBy Tab. 4 we have:\n\n$$\\begin{align*}\n\\text{LVar} & \\quad \\frac{\\text{PolyVar}}{\\frac{\\text{LVar}}{G(\\Gamma_1), \\Phi; \\tilde{y} \\vdash \\tilde{x} \\triangleright \\tilde{M}}{G(\\Gamma_1), \\Phi; \\Phi; G(\\Delta_1, \\Delta_2), \\Theta_1 \\vdash B^k_{\\tilde{x}}(V(\\tilde{r}, u_i)) \\triangleright \\sigma}}{G(\\Gamma), \\Phi; \\Phi; G(\\Delta_1 \\Delta_2), \\Theta_1 \\vdash B^k_{\\tilde{x}}(V(\\tilde{r}, u_i)) \\triangleright \\sigma} \\\\\n\\end{align*}$$\n\n(129)\n\nWe construct auxiliary derivations parametrized by $k$ and denoted by $d(k)$. If $k = n$, derivation $d(n)$ is defined as:\n\n$$\\begin{align*}\n\\text{Lem.} \\ A_3 & \\quad \\frac{\\text{LVar}}{G(\\Gamma), \\Phi; \\tilde{y} \\vdash \\tilde{x} \\triangleright \\tilde{M}}{G(\\Gamma), \\Phi; \\Phi; G(\\Delta_1 \\Delta_2), \\Theta_1 \\vdash B^k_{\\tilde{x}}(V(\\tilde{r}, u_i)) \\triangleright \\sigma} \\\\\n\\end{align*}$$\n\n(130)\n\nwhere $\\sigma = \\prod_{i \\in \\{1, \\ldots, n\\}} \\tilde{n}_i/\\tilde{z}_i$ with $\\tilde{n}_i = (r_{i1}, \\ldots, r_{il_{i+|G(S_i)|-1}})$ for $i = \\{1, \\ldots, n\\}$.\n\n$$\\begin{align*}\n\\text{Lem.} \\ A_2 & \\quad \\frac{\\text{LVar}}{G(\\Gamma), \\Phi; \\Phi; G(\\Delta_1 \\Delta_2), \\Theta_1 \\vdash B^k_{\\tilde{x}}(V(\\tilde{r}, u_i)) \\triangleright \\sigma} \\\\\n\\end{align*}$$\n\n(131)\n\n$$\\begin{align*}\n\\text{LVar} & \\quad \\frac{\\text{PolyAbs}}{\\frac{\\text{PolyAbs}}{G(\\Gamma), \\Phi; G(\\Delta_1 \\Delta_2), \\Theta_1 \\vdash B^k_{\\tilde{x}}(V(\\tilde{r}, u_i)) \\triangleright \\sigma}}{G(\\Gamma), \\Phi; G(\\Delta_1 \\Delta_2), \\Theta_1 \\vdash B^k_{\\tilde{x}}(V(\\tilde{r}, u_i)) \\triangleright \\sigma} \\\\\n\\end{align*}$$\n\n(132)\nOtherwise, if \\( k \\in \\{1, ..., n - 1 \\} \\), derivation \\( d(k) \\) is as follows:\n\n\\[\n\\begin{align*}\n\\text{PolyAbs} & \\quad d(k + 1) & \\quad \\text{PolyVar} & \\quad \\frac{\\mathcal{G}(\\Gamma), \\Phi; \\emptyset; \\tilde{z}_k \\vdash G(S_k) \\vdash G(S_{k+1})}{\\mathcal{G}(\\Gamma), \\Phi; G(\\Lambda); \\big( \\tilde{z}_1, \\ldots, \\tilde{z}_{n-k} \\big) : (G(S_1), \\ldots, G(S_{n-k}))} \\\\\n& \\quad \\frac{\\lambda \\tilde{z}_k, \\ e^{\\tilde{k}+1} ! (\\lambda \\tilde{z}_{k+1}, \\ldots, e^n ! (\\lambda \\tilde{z}_n, Q), 0 \\ldots). 0 \\vdash G(S_1) \\vdash \\emptyset}{(\\tilde{x}_1) \\vdash} (133)\n\\end{align*}\n\\]\n\nThe following tree proves this case:\n\n\\[\n\\begin{align*}\n\\text{PolyRcv} & \\quad d(1) & \\quad \\text{PolyVar} & \\quad \\frac{\\mathcal{G}(\\Gamma_1), \\Phi; G(\\Lambda); \\emptyset \\vdash \\tilde{z} \\vdash M}{\\mathcal{G}(\\Gamma_1), \\Phi; \\emptyset; G(\\Delta_1, \\Delta_2), \\emptyset \\vdash B^k (V (\\tilde{r}, u_i)) \\vdash \\emptyset} (134)\n\\end{align*}\n\\]\n\n\\section{C.2 Proof of Thm. 3.28}\n\n\\textbf{Proof.} By assumption \\( \\Gamma; \\emptyset; \\Delta, \\Delta_{\\mu} \\vdash P \\vdash \\emptyset \\). Then, by applying Lem. A.2 we have:\n\n\\[\n\\Gamma_{\\sigma}; \\emptyset; \\Delta_{\\sigma}, \\Delta_{\\mu_{\\sigma}} \\vdash P_{\\sigma} \\vdash \\emptyset (135)\n\\]\n\nBy Thm. 3.27 on (135) we have:\n\n\\[\n\\mathcal{G}(\\Gamma_{\\sigma}), \\Phi; G(\\Delta_{\\sigma}), \\emptyset \\vdash B^k (P_{\\sigma}) \\vdash \\emptyset (136)\n\\]\n\nwhere \\( \\emptyset \\) is balanced with \\( \\text{dom}(\\emptyset) = \\{ c_k, c_{k+1}, \\ldots, c_{k+|P|-1} \\} \\cup \\{ v_{k+1}, \\ldots, v_{k+|P|-1} \\} \\), and \\( \\emptyset(c_k) = ? (;) \\). \\( \\emptyset \\) is balanced, and \\( \\Phi = \\prod_{r \\in \\text{dom}(\\emptyset)} e^{r : \\mathcal{R}(\\Delta_{\\mu}(r))} \\rightarrow \\emptyset \\). By assumption, \\( f v(P) = \\emptyset \\).\n\nBy Def. 3.25, we shall prove the following judgment:\n\n\\[\n\\mathcal{G}(\\Gamma_{\\sigma}); \\emptyset; G(\\Delta_{\\sigma}), G(\\Delta_{\\mu_{\\sigma}})(\\nu \\tilde{v})(\\nu \\tilde{v}_{\\sigma}) \\left( \\prod_{r \\in \\tilde{v}} e^{r \\vdash (b_r \\vdash r \\vdash ?)} | B^k (P_{\\sigma}) \\right) (137)\n\\]\n\nwhere: \\( k > 0; \\tilde{v} = \\text{rn}(P); \\tilde{r} = (r_1, \\ldots, r_{|G(S)|}) \\) for each \\( r \\in \\tilde{v} \\).\n\nWe know \\( \\text{dom}(\\Delta_{\\mu}) = \\tilde{v} \\). We assume that recursive session types are unfolded. By Def. 3.4 and Def. 3.18, for \\( r \\in \\text{dom}(\\Delta_{\\mu}) \\) we have:\n\n\\[\n\\mathcal{G}(\\Delta_{\\mu})(r) = \\mathcal{R}(\\Delta_{\\mu}(r)) = \\mathcal{R}^*(\\Delta_{\\mu}(r))\n\\]\n\nWe use a family of auxiliary derivations parametrized by \\( r \\in \\tilde{v} \\).\n\n\\[\n\\begin{align*}\n\\text{LVar} & \\quad \\frac{\\mathcal{G}(\\Gamma_{\\sigma}), \\Phi; b: \\mathcal{R}(\\Delta_{\\mu}(r)) \\rightarrow \\emptyset; \\emptyset \\vdash}{b \\vdash \\mathcal{R}^*(\\Delta_{\\mu}(r)) \\rightarrow \\emptyset} \\quad \\text{PolySess} & \\quad \\frac{\\mathcal{G}(\\Gamma_{\\sigma}), \\Phi; \\tilde{r}: \\mathcal{R}(\\Delta_{\\mu}(r)) \\vdash}{\\tilde{r} \\vdash \\mathcal{R}^*(\\Delta_{\\mu}(r))} \\\\\n\\text{PolyApp} & \\quad \\frac{\\mathcal{G}(\\Gamma_{\\sigma}), \\Phi; b: \\mathcal{R}^*(\\Delta_{\\mu}(r)) \\rightarrow \\emptyset; \\tilde{r}: \\mathcal{R}^*(\\Delta_{\\mu}(r)) \\vdash (b \\tilde{r})}{\\mathcal{G}(\\Gamma_{\\sigma}), \\Phi; b: \\mathcal{R}^*(\\Delta_{\\mu}(r)) \\rightarrow \\emptyset; \\tilde{r}: \\mathcal{R}^*(\\Delta_{\\mu}(r)) \\vdash (b \\tilde{r})} (137)\n\\end{align*}\n\\]\nWe will then use:\n\n\\[\n\\text{Par} \\quad \\text{(v)} - 1 \\text{ times}\n\\]\n\nwhere we apply Rule Par \\(\\text{v} - 1\\) times and for every \\(r \\in \\text{v}\\) we apply derivation (138). Notice that by Def. 3.4 and Def. 3.18 we have\n\n\\[\nG(\\Delta_\\sigma) = \\prod_{r \\in \\text{v}} c_r ?(b) \\cdot (b \\tilde{r})\n\\]\n\nThe following tree proves this case:\n\n\\[\n\\text{Par} \\quad \\text{Sess} \\quad \\text{PolyRes} \\quad \\text{PolyResS}\n\\]"}}},{"rowIdx":95,"cells":{"id":{"kind":"string","value":"7dde90c06111c22b1f6a28be1fe2e74fb5870c33"},"text":{"kind":"string","value":"Keywords: behavioral subtype, subtyping, equational logic, proof theory.\n\n\n1991 Mathematics Subject Classification. Primary: 68Q65 Secondary: 68N05, 68N15, 68Q60.\n\nSubmitted for publication.\n\nCopyright © Gary T. Leavens and Don Pigozzi, 2002.\n\nDepartment of Computer Science\n226 Atanasoff Hall\nIowa State University\nAmes, Iowa 50011-1041, USA\nEQUATIONAL REASONING WITH SUBTYPES\n\nGARY T. LEAVENS AND DON PIGOZZI\n\nAbstract. Using equational logic as a specification language, we investigate the proof theory of behavioral subtyping for object-oriented abstract data types with immutable objects and deterministic methods that can use multiple dispatch. In particular, we investigate a proof technique for correct behavioral subtyping in which each subtype's specification includes terms that can be used to coerce its objects to objects of each of its supertypes. We show that this technique is sound, using our previous work on the model theory of such abstract data types. We also give an example to show that the technique is not complete, even if the methods do not use multiple dispatch, and even if types specified are term-generated. In preparation for the results on equational subtyping we develop the proof theory of a richer form of equational logic that is suitable for dealing with subtyping and behavioral equivalence. This gives some insight into question of when our proof techniques can be make effectively computable, but in general behavioral consequence is not effectively computable.\n\n1. Introduction\n\nThe concept of behavioral subtyping plays a foundational role in the specification and verification of object-oriented programs. While we and others have investigated model-theoretic notions of behavioral subtyping [5, 21, 23, 28], model-theoretic techniques do not lead directly to effectively computable ways to prove correct behavioral subtyping. For this purpose one must look to proof-theoretic techniques. The main motivation for our study is to bridge the gap between more practical proof-theoretic work and our sound and complete model-theoretic characterization of behavioral subtyping (for immutable types with deterministic methods that may use multiple dispatch) [23].\n\nIn this paper we work with equational specifications and a particular technique for verifying correct behavioral subtyping. Equational logic [11] is at the heart of many proof-theoretic techniques for reasoning about programs. Even in a Hoare logic, one often relies on equational reasoning to prove various facts about expressions. However we must deal\n\nDate: June 7, 2002.\n1991 Mathematics Subject Classification. Primary: 68Q65 Secondary: 68N05, 68N15, 68Q60.\nKey words and phrases. Behavioral subtyping, equational logic, proof theory.\nThe work of both authors is supported in part by the National Science Foundation under grants CCR-9803843 and CCR-0097907. The work of Leavens was also supported in part by NSF grant CCR-0113181.\nwith a more complex form of equational logic that is suitable for reasoning about both subtyping and behavioral equivalence.\n\nWe consider equational specifications that are augmented, for each type, by a specification of how to coerce an object of that type to each of its direct supertypes. Such a formal system of coercion terms is similar to the system of implicit coercion functions considered in Reynolds’s category-sorted algebras [32]. These coercions are also present in the specifications that other authors have used in their work on behavioral subtyping [2, 5, 10, 26].\n\nIn our work, the coercions take the from of equations, and we show that if all the coercion equations are behavioral consequences of the given equational specification, then the given specification is necessarily correctly behaviorally subtyped. This is done by applying the algebraic soundness theorem from our work on the model theory of behavioral subtyping [23].\n\nWe also investigate the limitations of this technique. In particular, we give an equational specification of an ADT that is correctly behaviorally subtyped, but for which no system of coercion terms exists. Since we allow multiple dispatch and models that are not term-generated, we also discuss how our results are affected by more restrictive conditions on our specification and its models.\n\nThe basis of the theory of correct behavioral subtyping is behavioral equivalence. A systematic development of a part of the theory of behavioral equivalence, in the context of correct subtyping, is given in [22]. A more extensive development that does not involve subtyping can be found in a series of papers by Goguen and Malcolm on hidden algebras; see [15, 16] and the many papers referenced there.\n\nTo reason effectively about behavioral equivalence and subtyping, we introduce the concept of behavioral consequence. Coercion allows us to reduce the problem of correct behavioral subtyping to one of verifying that certain equations are behavioral consequences of the given specification. While the completeness and soundness theorems for equational logic show that ordinary equational consequence is effectively computable, behavioral consequence is in general not [6]. The first part of the paper is devoted to developing a proof theory for behavioral consequence that in many practical situations does give an effective method for verifying behavioral consequence, and hence that a given specification is correctly behaviorally subtyped.\n\nThe proof theory of behavioral consequence is based on coinduction. Various methods of applying coinduction in a reasonably efficient way have been investigated in the literature (see for example [15, 33, 34]). We focus in this paper on one such method that uses the notion of a local context. One of the main results is the closure of behavioral consequence under equational consequence, i.e., that any equation that is provable in ordinary equational logic from a set of behavioral consequences of an equational specification is itself a behavioral consequence. This turns out to be an effective method for proving correct behavioral subtyping in many cases where all the equations associated with a given set of coercion functions can be proved by the methods of equational logic from just a few judiciously chosen ones which have been shown to be behavioral consequences directly by coinduction. An example of this kind is given in some detail. It is part of a running example that includes the equational specification of an object-oriented type of geometric points with its subtype, colored points. We return to this example several times throughout the paper to illustrate\nthe more important definitions and results as they are obtained. In particular we verify by\nmeans of coercions that the specification is correctly behaviorally subtyped.\n\nIn the last part of the paper we discuss some further aspects of this work. For example we\nshow why, for the study of correct behavioral subtyping, order-sorted algebras do not form\nan appropriate basis for the model theory. There is also a discussion of related work and\nconclusions. The paper ends with an appendix on the model theory of correct behavioral\nsubtyping.\n\n2. EQUATIONAL LOGIC WITH SUBTYPING\n\nIn this section, we specify the equational logic that forms the basis of the logic of behav-\nioral equivalence developed in the next section. The novel feature is the way subtyping is\nincorporated in the logic.\n\n2.1. Signatures with Subtyping. We use essentially the same notion of a signature\nwith subtyping from our earlier work [21, 23], which is itself adapted from the signatures\nReynolds uses [32]. However under the influence of the “hidden algebra school” [15, 16] the\nseparation into visible and hidden parts is made more explicit.\n\nDefinition 2.1. A visible data signature \\( \\Psi = (\\text{VIS}, \\text{Op}_{\\text{VIS}}, \\text{AdmisType}_{\\text{VIS}}) \\) consists of:\n\n(i) A nonempty set \\( \\text{VIS} \\) of visible types.\n(ii) A nonempty set \\( \\text{Op}_{\\text{VIS}} \\) of visible operation symbols.\n(iii) A function \\( \\text{AdmisType}_{\\text{VIS}} \\) from \\( \\text{Op}_{\\text{VIS}} \\) to \\( \\text{VIS}^+ \\), the set of finite nonempty sequences\nof element of \\( \\text{VIS} \\). For each \\( g \\in \\text{Op}_{\\text{VIS}} \\), \\( \\text{AdmisType}(g) = (V_1, \\ldots, V_n, V) \\), which\nis normally written in the form \\( V_1, \\ldots, V_n \\rightarrow V \\), is called the admissible type of \\( g \\).\nMoreover, \\( (V_1, \\ldots, V_n) \\) is called the admissible type domain and \\( V \\) the admissible\nresult type of \\( g \\). □\n\nDefinition 2.2. A hidden signature with subtyping \\( \\Sigma = (\\Psi, \\text{HID}, \\leq, \\text{Op}_{\\text{HID}}, \\text{ResType}_{\\text{HID}}) \\)\nconsists of:\n\n(i) A visible signature \\( \\Psi = (\\text{VIS}, \\text{Op}_{\\text{VIS}}, \\text{AdmisType}_{\\text{VIS}}) \\).\n(ii) A nonempty set \\( \\text{Op}_{\\text{HID}} \\) of hidden operation symbols,\n(iii) A subtype relation \\( \\leq \\), which is a preorder on \\( \\text{HID} \\). If \\( S \\leq T \\), then \\( S \\) is a subtype\nof \\( T \\), and \\( T \\) is a supertype of \\( S \\). \\( \\leq \\) is extended to a preordering of all of \\( \\text{TYPE} \\) by\nsetting \\( V \\leq V \\) for each \\( V \\in \\text{VIS} \\); thus \\( \\leq \\) is the discrete ordering on \\( \\text{VIS} \\).\n(iv) An \\( \\mathbb{N} \\)-indexed family \\( \\text{Op}_{\\text{HID}} = \\langle \\text{Op}_{\\text{HID}, n} : n \\in \\mathbb{N} \\rangle \\) of hidden operation symbols,\nwhere \\( \\mathbb{N} \\) is the set of natural numbers \\( \\{0, 1, 2, \\ldots\\} \\). \\( \\text{Op}_{\\text{HID}, n} \\) is the set of hidden\noperation symbols of rank \\( n \\); it is assumed to be disjoint from \\( \\text{Op}_{\\text{VIS}} \\) for each \\( n \\).\n(v) An \\( \\mathbb{N} \\)-indexed family \\( \\text{ResType}_{\\text{HID}} = \\langle \\text{ResType}_{\\text{HID}, n} : n \\in \\mathbb{N} \\rangle \\) of partial functions\n\\( \\text{ResType}_{\\text{HID}, n} : \\text{Op}_n \\times \\text{TYPE}^n \\rightarrow \\text{TYPE} \\) for each \\( n \\in \\mathbb{N} \\) with the following two\nproperties.\n(a) If \\( \\text{ResType}_{\\text{HID}, n}(g, S_1, \\ldots, S_n) = S \\), then at least one of \\( S_1, \\ldots, S_n, S \\) is a hid-\nden type.\n(b) Each of the functions \\( \\text{ResType}_{\\text{HID},n} : \\text{Op}_{\\text{HID},n} \\times \\text{TYPE}^n \\rightarrow \\text{TYPE} \\) is monotonic in its second argument in the sense of the following subtype condition:\n\n\\[\n\\text{ResType}(g, S_1, \\ldots, S_n) \\leq \\text{ResType}(g, T_1, \\ldots, T_n).\n\\]\n\nIt is implicit in the subtype condition that if \\( \\text{ResType}_{\\text{HID},n}(g, T_1, \\ldots, T_n) \\) is defined, then so is \\( \\text{ResType}_{\\text{HID},n}(g, S_1, \\ldots, S_n) \\) if \\( (S_1, \\ldots, S_n) \\leq (T_1, \\ldots, T_n) \\).\n\n\\( \\square \\)\n\n\\( \\text{ResType}_{\\text{HID}} \\) gives the nominal result type for a given hidden operation and sequence of argument types.\n\nThe hidden operations of a signature are polymorphic in the sense that each may have multiple admissible types. A type such as \\( T_1, \\ldots, T_n \\rightarrow T \\) is called an admissible type of \\( g \\) if \\( \\text{ResType}_{\\text{HID},n}(g, T_1, \\ldots, T_n) = T \\); in this case \\( (T_1, \\ldots, T_n) \\) is said to be an admissible type domain, and \\( T \\) an admissible result type of \\( g \\). The defining properties of \\( \\text{ResType}_{\\text{HID}} \\) and the subtyping relation guarantee that, if \\( T_1, \\ldots, T_n \\rightarrow T \\) and \\( S_1, \\ldots, S_n \\rightarrow S \\) are two admissible types of a hidden operation \\( g \\) and \\( T \\) is visible, then so is \\( S \\) and in fact they are equal. Similarly for argument types: for each \\( i \\leq n \\), if \\( T_i \\) is visible, then so is \\( S_i \\) and they are equal.\n\nThe combined set of visible and hidden operation symbols is denoted by \\( \\text{Op} \\) and the range of \\( \\text{ResType}_{\\text{HID}} \\) is extended to include visible operations. Thus, for each visible \\( g \\in \\text{Op}_n \\), \\( \\text{ResSort}(g, T_1, \\ldots, T_n) \\) is defined and equal to \\( T \\) if and only if \\( T_1, \\ldots, T_n \\rightarrow T \\) is the (unique) admissible type of \\( g \\).\n\nThe hidden operations are also called methods; these are partitioned into attributes, or destructors, whose admissible result type is visible (and hence unique), and constructors, whose admissible result types are all hidden. The methods are also partitioned into unimethods, those whose admissible type domains contain only one hidden type, and the multimethods, whose admissible type domains contain two or more hidden types. (As we have observed, the definition of a signature with subtyping guarantees all admissible type domains contain the same number of hidden types).\n\nWe assume a fixed countably infinite universe \\( \\text{Var} \\) of (untyped) variable symbols. The set \\( \\text{TM}_\\Sigma \\) of all (untyped) \\( \\Sigma \\)-terms are defined inductively in the usual way: \\( \\text{Var} \\subseteq \\text{TM}_\\Sigma \\) and, for every \\( n \\in \\mathbb{N} \\), \\( g \\in \\text{Op}_n \\), and \\( t_1, \\ldots, t_n \\in \\text{TM}_\\Sigma \\), \\( g(t_1, \\ldots, t_n) \\in \\text{TM}_\\Sigma \\); in particular, \\( g \\in \\text{TM}_\\Sigma \\) for every \\( g \\in \\text{Op}_0 \\). A term that is not a variable is completely visible if every operation occurring in it is visible. It is partially hidden otherwise, i.e., if it contains an occurrence of at least one hidden operation.\n\n**Example 2.3.** As an example of a signature with subtyping, let \\( \\Sigma_{pt} \\) be a hidden signature with the three types: \\( \\text{int}, \\text{Pt}, \\) and \\( \\text{Cpt} \\). The idea behind this example is that the type \\( \\text{Pt} \\) represents two-dimensional points, and the type \\( \\text{Cpt} \\) represents two-dimensional points that also have a color. In this example, the only visible type is \\( \\text{int} \\), and the subtype relation is such that \\( T \\leq T \\), for each type \\( T \\), and also \\( \\text{Cpt} \\leq \\text{Pt} \\). The operations and their admissible types for \\( \\Sigma_{pt} \\) are given in Figure 1. The operations on points also work on colored points, as they must according to the subtype condition. For example, the operation \\( x \\) can be used to extract the \\( x \\) coordinate from a point or a colored point. Note that when one of\nVisible operations\n0 : int, 1 : int,\nsucc : int → int, pred : int → int,\nadd : int, int → int, sub : int, int → int.\n\nUnimethod attributes\nx : Pt → int, y : Pt → int,\nx : Cpt → int, y : Cpt → int,\ncolor : Cpt → int.\n\nMultimethod attributes\nxdiff : Pt, Pt → int, xdiff : Cpt, Pt → int,\nxdiff : Pt, Cpt → int, xdiff : Cpt, Cpt → int.\n\nUnimethod constructors\nPtOrigin : Pt, CptOrigin : Cpt,\nmovex : Pt, int → Pt, movey : Pt, int → Pt,\nmovex : Cpt, int → Cpt, movey : Cpt, int → Cpt,\nchange : Cpt, int → Cpt,\n\nFigure 1. Operations and their admissible types for $\\Sigma_{pt}$.\n\nthe operations movex or movey is applied to an object of type Cpt, it is required by the signature to return a Cpt object.\n\nA signature with subtyping is capable of modeling “multimethods.” In an object-oriented (OO) programming language with multimethods, a call to an operation can be dispatched to a method body based on the types of more than one of its arguments. An example is the operation xdiff in the signature $\\Sigma_{pt}$ above. Many OO languages do not support multimethods, however, so it is interesting to study more restricted forms of signatures. Many of these lie within the scope of the following definition. A hidden signature with subtyping, $\\Sigma$, has only unary methods, or is a unimethod signature, if every method is a unimethod, i.e., if, for every $n \\in \\mathbb{N}$ and every $g \\in Op_n$, if $T_1, \\ldots, T_n$ is an admissible type domain of $g$, then $T_i \\in \\text{VIS}$ for at most one $1 \\leq i \\leq n$.\n\nThe signature $\\Sigma_{pt}$ above is not a unimethod signature. However, if one deletes the multimethod xdiff, then it becomes one. Note that movex, movey, add, and sub are unary methods, because int is a visible type.\n\nIn the general development below we assume a fixed signature with subtyping, $\\Sigma$.\n\n2.2. Typing. An element $(t, T)$ of $\\text{Tm}_\\Sigma \\times \\text{TYPE}$ is called a typing expression or simply a typing and is written $t : T$. A finite sequence of typing expressions $\\langle x_1 : T_1, \\ldots, x_n : T_n \\rangle$ such that $x_1, \\ldots, x_n$ are distinct variables is called a type context. $H$ can also be regarded as a finite function, where $H(x_i) = T_i$, for $1 \\leq i \\leq n$, and $\\{x_1, \\ldots, x_n\\}$ is the domain of $H$. The set of all type contexts is denoted by $\\text{TCON}$.\n\n$H$ is a type subcontext of another type context $K$, and $K$ is a type supercontext of $H$, in symbols $H \\subseteq K$, if $H$ is a subsequence of $K$, equivalently, if $H$ as a function is the restriction of $K$ to some subset of its domain. Type contexts $H$ and $K$ are disjoint if their\ndomains are disjoint and they are consistent if \\( H \\cup K \\) is a type context (i.e., \\( H(x) = K(x) \\)) for each variable \\( x \\) common to the domains of \\( H \\) and \\( K \\).\n\nThe following are the typing rules for terms [1, 21, 23].\n\n\\[\n\\begin{align*}\n\\text{(ident)} & \\quad \\Sigma; H \\vdash t: T, \\quad \\text{if } x: T \\in H \\\\\n\\text{(op-call)} & \\quad \\Sigma; H \\vdash t_1: T_1, \\ldots, \\Sigma; H \\vdash t_n: T_n \\\\\n& \\quad \\quad \\quad \\Sigma; H \\vdash g(t_1, \\ldots, t_n): T, \\quad \\text{if ResType}(g, T_1, \\ldots, T_n) = T,\n\\end{align*}\n\\]\n\nA term \\( t \\) is of nominal \\( H \\)-type (or simply of \\( H \\)-type) \\( S \\) in \\( \\Sigma \\), in symbols \\( \\Sigma; H \\vdash_{\\text{nom}} t: S \\), if the typing expression \\( t: S \\) is derivable from \\( \\Sigma \\) and \\( H \\) using the two typing rules: (ident) and (op-call). If the \\( H \\)-type of a term is defined we say that it is well \\( H \\)-typed. For example, if \\( H_{p,x} \\) is \\((p: \\text{Cpt}, x: \\text{int})\\), then \\text{movex}(p, 1)\\) is well \\( H_{p,x}\\)-typed, in fact of \\( H_{p,x}\\)-type \\( \\text{Cpt} \\) because \\( \\Sigma_{pt}; H_{p,x} \\vdash_{\\text{nom}} \\text{movex}(p, 1): \\text{Cpt} \\). When we use the expression “\\( t[x_1: T_1, \\ldots, x_n: T_n] \\)” synonymously for “\\( t \\)” it is understood that we are assuming that \\( t \\) is well \\( H \\)-typed with \\( H = \\langle x_1: T_1, \\ldots, x_n: T_n \\rangle \\). If the nominal \\( H \\)-type of a term is defined, it is easy to see that it is unique. Moreover, if \\( t \\) is well \\( H \\)-typed, it is well \\( H' \\)-typed for every type supercontext \\( H' \\) of \\( H \\), and its nominal \\( H \\)- and \\( H' \\)-types are the same.\n\nWhen the type context is irrelevant or understood from context we often say simply that a term is well typed and speak of its nominal type or even just of its type. Clearly each subterm of a well typed term is well typed. The typing expression “\\( t: S \\)” is often used synonymously for “\\( t \\)” under the implicit assumption that \\( t \\) is well typed and that \\( T \\) is its type. For example, \\text{movex}(p, 1)\\) is well typed, because \\( \\Sigma_{pt}; (p: \\text{Cpt}) \\vdash_{\\text{nom}} \\text{movex}(p, 1): \\text{Cpt} \\).\n\nIf \\( t = t[x_1: T_1, \\ldots, x_n: T_n] \\), \\( (S_1, \\ldots, S_n) \\leq (T_1, \\ldots, T_n) \\), and \\( t_1; S_1, \\ldots, t_n; S_n \\), then the result of simultaneously substituting \\( t_i; S_i \\) for \\( x_i: T_i \\) in \\( t \\), for each \\( 1 \\leq i \\leq n \\), is denoted by \\( t[t_1, \\ldots, t_n] \\).\n\n**Lemma 2.4** (Subtype Condition for Terms). Suppose \\( \\Sigma; H \\vdash_{\\text{nom}} t[x_1: T_1, \\ldots, x_n: T_n] : T \\), \\( H' \\) is a type context, and \\( \\Sigma; H' \\vdash_{\\text{nom}} t_i; S_i \\) for \\( i \\leq n \\). If \\( (S_1, \\ldots, S_n) \\leq (T_1, \\ldots, T_n) \\), then \\( t[t_1, \\ldots, t_n] \\) is well \\( H' \\)-typed, and if it is of nominal \\( H' \\)-type \\( S \\), then \\( S \\leq T \\).\n\n**Proof.** By structural induction on \\( t \\) using the subtype condition for operations. \\( \\Box \\)\n\nA term \\( t \\) is said to be of subsumptive \\( H \\)-type \\( S \\) in \\( \\Sigma \\), in symbols \\( \\Sigma; H \\vdash_{\\text{sub}} t: S \\), if the typing expression \\( t: S \\) is derivable from \\( \\Sigma \\) and \\( H \\) using the following rule of (subsumption), in addition to the rules (ident) and (op-call).\n\n\\[\n\\begin{align*}\n\\text{(subsumption)} & \\quad \\Sigma; H \\vdash t: S, \\quad \\text{if } S \\leq T.\n\\end{align*}\n\\]\n\nFor example, besides its nominal type, \\text{movex}(\\text{CptOrigin}(0), 1) : \\text{Cpt} also has subsumptive type \\( \\text{Pt} \\). According to the following lemma, whose proof is straightforward, a term has a subsumptive type if and only if it is well typed, and, moreover, its subsumptive types are exactly the supertypes of its nominal type.\n\n**Lemma 2.5** (Subsumption Lemma). If \\( \\Sigma; H \\vdash_{\\text{sub}} t: S \\), then \\( t \\) is well \\( H \\)-typed, and if \\( T \\) is its nominal \\( H \\)-type, then \\( T \\leq S \\). \\( \\Box \\)\n\nAnother way of formulating this lemma is that, in the derivation of a subsumptive \\( H \\)-type of \\( t \\), the subsumption rule need only be applied once, and as the last step of the derivation.\n2.3. Algebras.\n\nDefinition 2.6. A $\\Sigma$-algebra $A = \\langle A, \\{ g^A : g \\in \\text{Op} \\} \\rangle$ consists of the following:\n\n- A TYPE-indexed family of sets $A = \\{ A_T : T \\in \\text{TYPE} \\}$ called the \\textit{carrier} of $A$.\n- A partial function $g^A_{\\sigma} : (\\bigcup_{S \\subseteq \\text{TYPE}} A_S)^n \\rightarrow \\bigcup_{S \\subseteq \\text{TYPE}} A_S$ for each $n \\in \\mathbb{N}$ and $g \\in \\text{Op}_n$, called the \\textit{interpretation} of $g$, with the property that, for every admissible type $T_1, \\ldots, T_n \\rightarrow S$ of $g$ and every $(a_1, \\ldots, a_n) \\in A_{T_1} \\times \\cdots \\times A_{T_n}$, $g^A(a_1, \\ldots, a_n)$ is defined and contained in $\\bigcup_{U \\subseteq S} A_U$.\n\nWe follow Reynolds [32], in contrast to Goguen and Meseguer [13, 17], in not requiring $A_S \\subseteq A_T$ when $S \\leq T$. However, Reynolds handles subtyping by means of an implicit coercion mapping between the domains $A_S$ and $A_T$ when $S \\leq T$, and this has essentially the effect of requiring $A_S$ and $A_T$ to be disjoint when $S \\neq T$. We take a middle ground. The domains of distinct types $S$ and $T$ need not be disjoint, nor do they have to be comparable when $S \\leq T$, and we do not formally require coercion functions. Note that, if $(a_1, \\ldots, a_n) \\in (A_{T_1} \\times \\cdots \\times A_{T_n}) \\cap (A_{S_1} \\times \\cdots \\times A_{S_n})$, then there is no ambiguity in the value of $g^A(a_1, \\ldots, a_n)$ when $T_1, \\ldots, T_n$ and $S_1, \\ldots, S_n$ are both admissible type domains of an operation symbol $g$, since the interpretation of $g$ is global and not localized to the admissible type domains.\n\nExample 2.7. A $\\Sigma_{pt}$-algebra, $PT$, is formed as follows. The carrier of the sort int, $PT_{\\text{int}}$, is $\\mathbb{Z}$, the set $\\{ \\ldots, -2, -1, 0, 1, 2, \\ldots \\}$ of integers. For the other sorts, the carrier sets are $PT_{\\text{Pt}} = \\{ x, y : x \\in \\mathbb{Z}, y \\in \\mathbb{Z} \\}$ and $PT_{\\text{Cpt}} = \\{ x, y, c : x \\in \\mathbb{Z}, y \\in \\mathbb{Z}, c \\in \\mathbb{Z} \\}$. The interpretations of the operations are given in Figure 2. Note that the operations movex and movey change the color when their argument is of type Cpt.\n\nIt is convenient, in some contexts, to consider the more restricted notion of Goguen and Meseguer’s order-sorted algebras [13, 17]. A $\\Sigma$-algebra $A$ is called \\textit{order-sorted} if $A_S \\subseteq A_T$ when $S \\leq T$. Thus, in order-sorted algebras, carrier sets satisfy the following property: $\\bigcup_{S \\leq T} A_S = A_T$.\n\nThe algebra $PT$ is not order-sorted, since $A_{PT} \\not\\subseteq A_{PT}$. However, it is possible to transform $PT$ into an order-sorted algebra by means of a general construction, described below.\n\nLet $A = \\{ \\{ A_T : T \\in \\text{TYPE} \\}, \\{ g^A : g \\in \\text{Op} \\} \\}$ be an arbitrary $\\Sigma$-algebra. For each $T \\in \\text{TYPE}$ let $A^0_T = \\bigcup_{S \\leq T} A_S$. Note that, because of the subtype condition, if $T_1, \\ldots, T_n$ is an admissible type domain of $g \\in \\text{Op}_n$, then $g^A$ is defined on $A^T_1 \\times \\cdots \\times A^T_n$. Thus $\\{ \\{ A^T_T : T \\in \\text{TYPE} \\}, \\{ g^A : g \\in \\text{Op} \\} \\}$ is a $\\Sigma$-algebra that we denote by $A^0$. Clearly $A^0$ is order-sorted; it is called the \\textit{order-sorted transform} of $A$. For example, by the above construction the $\\Sigma_{pt}$-algebra $PT^0$ is order-sorted.\n\nDefinition 2.8 (dynamic type, virtual type). An element of $A_T$ is said to be of \\textit{dynamic} type $T$. An element of $A^0_T$ is said to be of \\textit{virtual type} $T$; note that each element of dynamic type $S$ is of virtual type $T$ for every $T \\geq S$. \\hfill $\\square$\n\\[ 0^{PT} = 0 \\]\n\\[ 1^{PT} = 1 \\]\n\\[ \\text{succ}^{PT}(a) = a + 1 \\]\n\\[ \\text{pred}^{PT}(a) = a - 1 \\]\n\\[ \\text{add}^{PT}(a, b) = a + b \\]\n\\[ \\text{sub}^{PT}(a, b) = a - b \\]\n\\[ \\text{PtOrigin}^{PT} = \\langle 0, 0 \\rangle \\]\n\\[ \\text{CpPtOrigin}^{PT} = \\langle 0, 0, 0 \\rangle \\]\n\\[ x^{PT}(\\langle x, y \\rangle) = x \\]\n\\[ x^{PT}(\\langle x, y, c \\rangle) = x \\]\n\\[ y^{PT}(\\langle x, y \\rangle) = y \\]\n\\[ y^{PT}(\\langle x, y, c \\rangle) = y \\]\n\\[ \\text{color}^{PT}(\\langle x, y, c \\rangle) = c \\]\n\\[ \\text{xdiff}^{PT}(\\langle x_1, y_1, x_2, y_2 \\rangle) = x_1 - x_2 \\]\n\\[ \\text{add}^{PT}(\\langle x_1, y_1, x_2, y_2 \\rangle) = x_1 - x_2 \\]\n\\[ \\text{sub}^{PT}(\\langle x_1, y_1, x_2, y_2 \\rangle) = x_1 - x_2 \\]\n\\[ \\text{movex}^{PT}(\\langle x, y \\rangle, a) = \\langle x + a, y \\rangle \\]\n\\[ \\text{movey}^{PT}(\\langle x, y \\rangle, c) = \\langle x, y + a \\rangle \\]\n\\[ \\text{movey}^{PT}(\\langle x, y, c \\rangle, a) = \\langle x, y + a, y \\rangle \\]\n\\[ \\text{change}^{PT}(\\langle x, y, c \\rangle, d) = \\langle x, y, d \\rangle \\]\n\nFigure 2. Definitions of \\( PT \\)'s operation interpretations.\n\nAn algebra \\( A \\) is \\textit{nominal} if, for each \\( n \\in \\mathbb{N} \\), each \\( g \\in \\text{Op}_n \\), each admissible type \\( T_1, \\ldots, T_n \\to S \\) of \\( g \\), and all \\( a_1, \\ldots, a_n \\in A_{T_1} \\times \\cdots \\times A_{T_n} \\), \\( g^A(a_1, \\ldots, a_n) \\) is of dynamic type \\( S \\), i.e., \\( g^A(a_1, \\ldots, a_n) \\in AS \\).\n\nIf \\( A \\) is order-sorted, then every element of virtual type \\( T \\) is also of dynamic type \\( T \\); in fact this property characterizes order-sorted algebras. Thus every order-sorted \\( \\Sigma \\)-algebra is nominal. However, there are algebras that are nominal but not order-sorted; \\( PT \\) is one example. It is also easy to construct algebras that are not nominal (and hence also not order-sorted); for example, if one changes the algebra \\( PT \\), by making \\( \\text{PtOrigin} \\) return \\( \\langle 0, 0, 0 \\rangle \\), which is an element of the carrier set of \\( \\text{CpPt} \\), then this modified algebra would not be nominal.\n\n\\textbf{Definition 2.9} (dynamic and virtual environments). Let \\( A \\) be a \\( \\Sigma \\)-algebra, and also let \\( H = \\langle x_1; T_1, \\ldots, x_n; T_n \\rangle \\) be a type context. A \\textit{dynamic} (resp. \\textit{virtual}) \\( H \\)-environment in \\( A \\) is a sequence \\( \\bar{a} = \\langle a_1, \\ldots, a_n \\rangle \\) of elements of \\( A \\) such that \\( a_i \\) is of dynamic (resp. virtual) type \\( T_i \\), for each \\( i \\leq n \\).\n\n\\footnote{In our earlier work [23], we called dynamic environments “nominal.”}\nNote that every dynamic $H$-environment is virtual and that the two kinds of environments coincide just when the algebra is order-sorted. Although virtual environments are more general, we will be dealing mainly with dynamic environments, and hence the latter is taken to be the default kind of environment. Thus when we say “$H$-environment” without qualification we mean a dynamic $H$-environment.\n\nA dynamic or virtual $H$-environment can also be regarded as a finite function from the domain of $H$ to the corresponding elements in the environment. For example, if $H = \\langle x_1:T_1, \\ldots, x_n:T_n \\rangle$ and $\\bar{a} = \\langle a_1, \\ldots, a_n \\rangle$ is a dynamic or virtual $H$-environment, then $\\bar{a}(x_i) = a_i$.\n\nFor each type context $H$ we define the $H$-nominal $\\Sigma$-term algebra\n\n$$\\mathbf{Tm}_\\Sigma(H) = \\langle \\mathbf{Tm}(H), \\{ g^{\\mathbf{Tm}_\\Sigma(H)} : g \\in \\mathbf{Op} \\} \\rangle$$\n\nas follows. For each $T \\in \\mathbf{TYPE}$, $\\mathbf{Tm}_\\Sigma(H)_T$ is the set of all well $H$-typed terms of nominal $H$-type $T$. For each $g \\in \\mathbf{Op}_n$, each admissible type domain $(T_1, \\ldots, T_n)$ of $g$, and each sequence of well $H$-typed terms $t_1:T_1, \\ldots, t_n:T_n$, $g^{\\mathbf{Tm}_\\Sigma(H)}(t_1, \\ldots, t_n) = g(t_1, \\ldots, t_n)$. Thus the typing rule (op-call) guarantees that $\\mathbf{Tm}_\\Sigma(H)$ is a nominal $\\Sigma$-algebra. By definition the elements of $\\mathbf{Tm}_\\Sigma(H)$ of dynamic type $T$ are exactly the terms of nominal type $T$. So the type context $H$ is itself a dynamic $H$-environment of $\\mathbf{Tm}_\\Sigma(H)$, called the canonical dynamic environment. Again if, $H$ is irrelevant or understood from context, we refer simply to the nominal $\\Sigma$-term algebra, or even more simply the $\\Sigma$-term algebra.\n\nBy the subsumption lemma the elements of $\\mathbf{Tm}_\\Sigma(H)$ of virtual type $S$ are exactly the terms of subsumptive type $S$. Thus $\\mathbf{Tm}_\\Sigma(H)^\\circ$ is called the subsumptive $H$-term $\\Sigma$-algebra.\n\nIf $H = \\langle x_1:T_1, \\ldots, x_n:T_n \\rangle$ is a type context, $\\bar{a} = \\langle a_1, \\ldots, a_n \\rangle$ is an $H$-environment, and $t[x_1:T_1, \\ldots, x_n:T_n]:S$ is a well $H$-typed term, we write $t^\\Sigma[H][\\bar{a}]$ for the usual meaning of $t$ in the environment $\\bar{a}$ of $A$, i.e., the value it takes in $A$ when each variable $x_i$ takes the value $a_i$. It is inductively defined by $x_i^\\Sigma[H][\\bar{a}] = a_i$ and $g(t_1, \\ldots, t_k)^\\Sigma[H][\\bar{a}] = g^\\Sigma(t_1^\\Sigma[H][\\bar{a}], \\ldots, t_k^\\Sigma[H][\\bar{a}])$.\n\n**Definition 2.10** (satisfaction and validity of typing expressions). Let $A$ be a $\\Sigma$-algebra and $H = \\langle x_1:T_1, \\ldots, x_n:T_n \\rangle$ a type context. A typing expression $t:T$ is satisfied in a dynamic or virtual $H$-environment $\\bar{a}$ of $A$ if $t^\\Sigma[H][\\bar{a}]$ is defined (i.e., $t$ is well $H$-typed) and $t^\\Sigma[H][\\bar{a}] \\in A_T$. It is $H$-valid in $A$ if it is satisfied in every dynamic $H$-environment of $A$. In this case we say that $A$ is an $H$-model of $t:T$. □\n\n**Theorem 2.11** (Type Soundness and Completeness Theorem). Let $\\Sigma$ be a hidden signature with subtyping and $A$ a $\\Sigma$-algebra.\n\n(i) $A$ is nominal if and only if, for every type context $H$, every type $T$, and every well typed term $t$ of nominal $H$-type $T$, $A$ is an $H$-model of $t:T$.\n\n(ii) $A$ is order-sorted if and only if, for every type context $H$, every type $S$, and every well typed term $t$ of subsumptive $H$-type $S$, $A$ is an $H$-model of $t:S$.\n\nProof. In both parts the implications from left to right are proved by induction on the length of type deductions. The implications in the opposite direction are immediate. □\n\n2.4. Equations and Specifications. An equation over $\\Sigma$ is an ordered triple $(H,t,t')$ such that $H$ is a type context and $t$ and $t'$ are well $H$-typed terms with the same nominal\n$H$-type, which we refer to as the nominal type, or simply the type, of $(H, t, t')$. We normally write equations in the form $\\forall H(t = t')$. If the type context is irrelevant or understood from context we write $t = t'$ in place of $\\forall H(t = t')$. Since well typed terms have a unique nominal type in a given signature and type context, the nominal type of each side of the equation can be derived from the typing rules. By the subsumption lemma, if $t$ and $t'$ have the same nominal type then they have the same subsumptive types, and we take these to be the subsumptive types of the equation $\\forall H(t = t')$.\n\n**Definition 2.12** (equational specification).\n\n(i) A visible equational specification is a pair $\\langle \\Psi, E_{VIS} \\rangle$ where $\\Psi$ is a visible data signature and $E_{VIS}$ is a set of equations over $\\Psi$.\n\n(ii) A hidden equational specification is a pair $\\langle \\Sigma, E \\rangle$ where $\\Sigma$ is a hidden signature over the visible data signature $\\Psi$ and $E$ is the disjoint union of a set $E_{VIS}$ of equations over $\\Psi$ and a set $E_{HID}$ of equations over $\\Sigma$ such that each equation of $E_{HID}$ is of visible type but is not a $\\Psi$-equation, i.e., it contains at least one hidden operation symbol. We refer to $\\langle \\Sigma, E \\rangle$ a hidden specification over the visible specification $\\langle \\Psi, E_{VIS} \\rangle$, which is called the visible part of $\\langle \\Sigma, E \\rangle$. □\n\n**Example 2.13.** For example, let $E_{pt}$ consist of the equations over $\\Sigma_{pt}$ presented in Figure 3; then $\\langle \\Sigma_{pt}, E_{pt} \\rangle$ is a hidden equational specification whose visible part is given by the first group of equations in the figure. □\n\n**Example 2.14.** The equations in $E_{pt}$ do not require that the operations $\\text{movex}$ and $\\text{movey}$ preserve the color of a $\\text{Cpt}$ argument. However, this can be ensured by adding to $E_{pt}$ the first two additional equations given in Figure 4. This gives the set of equations $E_{cpt}$. □\n\nThe restriction to equations of visible type in a hidden equational specification is nonstandard but is natural from the perspective of operational semantics. That is, in operational terms, one views the equations as specifying the output of programs, which indirectly determine the behavior of the hidden data objects the programs manipulate. One can imagine that the program executes by taking visible data as input, forming hidden data objects by means of the constructors, and finally outputting visible data by means of the attributes. To reflect the fact that one can only observe the visible outputs of program executions, we restrict the underlying equational logic so that equality comparisons between hidden data is not allowed. The only notion of equality appropriate from this perspective is behavioral equivalence.\n\nThe restriction that only equations of visible type are allowed does not guarantee that an equational specification is consistent, and it does not guarantee that it is a conservative extension of its visible part. A stronger condition, however, can be used to guarantee consistency. One such condition is embodied in Goguen and Malcolm’s notion of a local equation [15]; they prove that if the hidden equations of a specification are local then the specification is consistent. It can also be shown that it is a conservative extension of its visible part.\n\n3In the standard formalization of multi-sorted equational logic each variable symbol is assumed to have an a priori type that never varies, and thus a type context is completely determined by its domain. In the standard formalization the equation $(H, t, t')$ would be denoted by $\\forall X(t = t')$ where $X$ is the domain of $H$. \nfor all \\( a : \\text{int}, b : \\text{int}, c : \\text{int}, i : \\text{int}, p : \\text{Pt}, p_1 : \\text{Pt}, p_2 : \\text{Pt}, \\)\n\n\\[\n\\begin{align*}\n\\text{succ}(0) &= 1 \\\\\n\\text{pred}(1) &= 0 \\\\\n\\text{pred}(\\text{succ}(a)) &= a \\\\\n\\text{succ}(\\text{pred}(a)) &= a \\\\\n\\text{add}(0, a) &= a \\\\\n\\text{add}(\\text{succ}(a), b) &= \\text{succ}(\\text{add}(a, b)) \\\\\n\\text{add}(\\text{pred}(a), b) &= \\text{pred}(\\text{add}(a, b)) \\\\\n\\text{sub}(a, 0) &= a \\\\\n\\text{sub}(a, \\text{succ}(b)) &= \\text{pred}(\\text{sub}(a, b)) \\\\\n\\text{sub}(a, \\text{pred}(b)) &= \\text{succ}(\\text{sub}(a, b))\n\\end{align*}\n\\]\n\n(Figure 3. The set of equations \\( E_{\\text{pt}} \\). Each of these is understood to be an \\( H \\)-equation where \\( H \\) is the type subcontext obtained from the one given at top of the figure by restricting to the variables actually occurring in the equation. For example, the type context of the two equations is empty, and the type context of the sixth equation is \\( \\{a : \\text{int}, b : \\text{int}\\} \\). We label the equations in the non-visible part for later use.)\n\n\\[\n\\begin{align*}\n(x-Pt-Origin) &\\quad x(Pt-Origin) = 0 \\\\\n(y-Pt-Origin) &\\quad y(Pt-Origin) = 0 \\\\\n(x-CPt-Origin) &\\quad x(CPt-Origin) = 0 \\\\\n(y-CPt-Origin) &\\quad y(CPt-Origin) = 0 \\\\\n(color-CPt-Origin) &\\quad \\text{color}(CPt-Origin) = 0 \\\\\n(x-movex) &\\quad x(\\text{movex}(p, i)) = \\text{add}(x(p), i) \\\\\n(y-movey) &\\quad y(\\text{movey}(p, i)) = \\text{add}(y(p), i) \\\\\n(y-movey) &\\quad y(\\text{movey}(p, i)) = y(p) \\\\\n(x-movey) &\\quad x(\\text{movey}(p, i)) = x(p) \\\\\n(xdiff) &\\quad xdiff(p_1, p_2) = \\text{sub}(x(p_1), x(p_2))\n\\end{align*}\n\\]\n\n(Figure 4. Equations in \\( E_{\\text{cpt}} \\) added to those in \\( E_{\\text{pt}} \\). The type context of each equation is to be understood to be the one given at top of the figure.)\n\n2.5. Model Theory. We now relate equations and their algebraic models.\n\n**Definition 2.15** (satisfaction and validity of equations). Let \\( A \\) be a \\( \\Sigma \\)-algebra. An equation \\( \\forall H(t = t') \\) is *satisfied* in a dynamic or virtual \\( H \\)-environment \\( \\bar{a} \\) of \\( A \\) if \\( t^A[\\bar{a}] = t'^A[\\bar{a}] \\). It is *valid* in \\( A \\) if it is satisfied in every dynamic \\( H \\)-environment of \\( A \\); we say that \\( A \\) is a *model* of \\( \\forall H(t = t') \\) in this event. □\n\nThe virtual environments of a \\( \\Sigma \\)-algebra \\( A \\) are exactly the dynamic environments of its order-sorted transform \\( A^\\circ \\). Thus an \\( H \\)-equation is satisfied in every virtual \\( H \\)-environment\nFor example, $PT$ is a model of the $\\langle p : Pt, i : \\text{int}\\rangle$-equation, $x(\\text{movex}(p, i)) = \\text{add}(x(p), i)$, since it is true in every $\\langle p : Pt, i : \\text{int}\\rangle$-environment, in $PT$, including non-dynamic ones such as $\\langle (18, 47, 342), 54 \\rangle$. Thus this equation is valid in both $PT$ and in $PT^\\circ$. However, equations are not, in general, true in virtual environments even when they hold in all dynamic environments. That is, an algebra may be a model of an equation without its order-sorted transform being a model. For example, while $PT$ is a model of the $\\langle p : Pt\\rangle$-equation $\\text{movex}(p, 0) = p$, $PT^\\circ$ is not a model of this equation, due to the (intentionally strange) definition of $\\text{movex}$. To see this, consider the non-dynamic environment $\\langle (18, 47, 342), \\rangle$, which binds the variable $p : Pt$ to the colored point $(18, 47, 342)$; in this environment, $\\text{movex}(p, 0)^{PT}[(18, 47, 342)] = (18, 47, 18)$, which is not the same as $p^{PT}[(18, 47, 342)] = (18, 47, 342)$. On the other hand, both the algebra $CPT$, whose carrier sets are the same as those in $PT$ and whose operations are described in Figure 5, and its order-sorted transform are models of this equation.\n\n**Definition 2.16** (models; nominal and order-sorted models). Let $\\langle \\Sigma, E \\rangle$ be an equational specification. The class of models of $\\langle \\Sigma, E \\rangle$, i.e., the class of all $\\Sigma$-algebras that are models of every equation in $E$ is denoted by $\\text{Mod}(E)$. The class of all nominal (resp. order-sorted) models of $E$, i.e., nominal (resp. order-sorted) algebras that are models of $\\langle \\Sigma, E \\rangle$, is denoted by $\\text{Mod}_{\\text{nom}}(E)$ (resp. $\\text{Mod}_{\\text{ord}}(E)$).\n\nThe class $\\text{Mod}(E)$ of all models of $\\langle \\Sigma, E \\rangle$ is called the loose semantics of $\\langle \\Sigma, E \\rangle$.\n\nWe note that, in general, $\\text{Mod}_{\\text{ord}}(E) \\subseteq \\text{Mod}_{\\text{nom}}(E)$. For example, $PT$ is a model of $\\langle \\Sigma_{pt}, E_{pt} \\rangle$; hence $PT$ is in $\\text{Mod}(E_{pt})$. Since $PT$ is both a nominal $\\Sigma_{pt}$-algebra and a model of each equation in $E_{pt}$, $PT$ is a nominal model of $\\langle \\Sigma_{pt}, E_{pt} \\rangle$, i.e., $PT \\in \\text{Mod}_{\\text{nom}}(E_{pt})$. But $PT$ is not a model of the additional equations in $E_{opt}$; indeed both of the equations in Figure 4 are invalid in $PT$. Therefore $PT$ is not a model of $\\langle \\Sigma_{pt}, E_{cpt} \\rangle$. On the other hand, $CPT$ is a model of $\\langle \\Sigma_{pt}, E_{cpt} \\rangle$; since $CPT$ is also nominal it is also a nominal model of $\\langle \\Sigma_{pt}, E_{cpt} \\rangle$; similarly, $CPT^\\circ$ is also a nominal model of $\\langle \\Sigma_{pt}, E_{cpt} \\rangle$.\n\nWe could have considered also a notion of virtual model, where the equations of $E$ are required to be satisfied in all virtual environments as well as all dynamic ones. But it is easy to see that an algebra is a virtual model in this sense if and only if its order-sorted transform is a model in the sense of Def. 2.16 so the notion is not needed; cf. the remarks following Def. 2.15.\nDefinition 2.17 (nominal and order-sorted consequence). An $H$-equation $\\forall H(t = t')$ over $\\Sigma$ is a nominal (resp. order-sorted) consequence of $\\langle \\Sigma, E \\rangle$, in symbols $E \\triangleright_{\\text{nom}} \\forall H(t = t')$ (resp. $E \\triangleright_{\\text{ord}} \\forall H(t = t')$), if it is valid in every nominal (resp. order-sorted) model of $\\langle \\Sigma, E \\rangle$. □\n\nIn the theory of specifications additional extra-equational conditions may be imposed in order to restrict the class of models. One natural restriction is to require all models to be term-generated; that is one could require that every element of the carrier of a model can be obtained by applying operations, starting from constants. If in addition the model is required to be initial in the category of all models, then the class of restricted models would contain only one algebra up to isomorphism, making it “categorical” [27, 29].\n\nBecause OO programming languages contain “abstract” types that are not term-generated, we do not restrict our study to term-generated models. However, a programming language will have a fixed set of built-in types, which correspond to our notion of visible types, and the class of reducts of the restricted models to these types, the visible reducts, will be categorical; this implies that the class of restricted models of the visible part of a hidden specification will be categorical. We refer to the class of restricted models of a hidden equational specification as VIS-categorical when we impose this restriction that the class of reducts of the visible part of the signature be term-generated and initial. Without any real loss of generality we will assume that, if the class of restricted models is VIS-categorical, then the visible reduct is fixed; that is, for every pair of restricted models, the visible reducts are the same. This so-called fixed data assumption is incorporated into the definition of a hidden specification in [16, 15], but is relaxed in some of the subsequent work on hidden algebras, e.g., [6, 34].\n\n2.6. Proof Theory. The formal proof system given in Figure 6 is essentially the one given in Ehrig and Mahr’s book [11, p. 111] appropriately modified to handle subtyping. In their book every variable has a preassigned type that is fixed at the beginning and consequently sets of variables play the role of type contexts; this accounts for most of the difference between our equational logic and that of Ehrig and Mahr.\n\nThe following two type-context-modifying rules, which are often taken as part of the formalism, are derivable from (invar) and will be used in the sequel.\n\n\\[\n\\begin{align*}\n\\text{(abstr)} & \\quad \\frac{E \\vdash \\forall H'(t = t')}{E \\vdash \\forall H(t = t')}, \\quad \\text{where } H' \\subseteq H \\\\\n\\text{(concr)} & \\quad \\frac{E \\vdash \\forall H(t = t')}{E \\vdash \\forall H \\setminus \\{y : T\\}, \\quad \\text{where } H = H' \\setminus \\{y : T\\}, \\quad \\text{and } T \\text{ is nominally nonvacuous in } H'}\n\\end{align*}\n\\]\n\nA type $T$ is said to be nominally (resp. subsumptively) vacuous in a type context $H$ if $\\text{Tm}_{\\Sigma}(H)_{T} = \\emptyset$ (resp. $\\text{Tm}_{\\Sigma}(H)_{T} = \\emptyset$).\n\nDefinition 2.18. Let $\\langle \\Sigma, E \\rangle$ be an equational specification. An equation over $\\Sigma$, $\\forall H(t = t')$, is nominally (resp. subsumptively) equationally provable from $E$, in symbols $E \\triangleright_{\\text{nom}} \\forall H(t = t')$ (resp. $E \\triangleright_{\\text{sub}} \\forall H(t = t')$), if there is a finite sequence of equations over $\\Sigma$ terminating in $\\forall H(t = t')$ such that each equation is either in $E$ or is directly derivable from preceding equations in the sequence by one of the inference rules in Figure 6 using the nominal (resp. subsumptive) forms of (cong) and (invar). □\n(axiom) \\[ E \\vdash \\forall H(t = t'), \\quad \\text{where } \\forall H(t = t') \\in E \\]\n\n(refl) \\[ E \\vdash \\forall H(t = t) \\]\n\n(sgm) \\[ E \\vdash \\forall H(t = t') \\quad E \\vdash \\forall H(t' = t) \\]\n\n(trans) \\[\nE \\vdash \\forall H(t = t') \\quad E \\vdash \\forall H(t' = t'') \\\\\n\\therefore E \\vdash \\forall H(t = t'')\n\\]\n\n(cong)\\text{nom} \\[ E \\vdash \\forall H(t_1 = t'_1), \\ldots, E \\vdash \\forall H(t_n = t'_n) \\]\n\\[ E \\vdash \\forall H(g(t_1, \\ldots, t_n) = g(t'_1, \\ldots, t'_n)), \\]\nwhere \\( \\forall H(t_1 = t'_1), \\ldots, \\forall H(t_n = t'_n) \\) are of nominal types \\( T_1, \\ldots, T_n \\), and \\( T_1, \\ldots, T_n \\) is an admissible domain of \\( g \\)\n\n(cong)\\text{sub} \\[ E \\vdash \\forall H(t_1 = t'_1), \\ldots, E \\vdash \\forall H(t_n = t'_n) \\]\n\\[ E \\vdash \\forall H(g(t_1, \\ldots, t_n) = g(t'_1, \\ldots, t'_n)), \\]\nwhere \\( \\forall H(t_1 = t'_1), \\ldots, \\forall H(t_n = t'_n) \\) are of subsumptive types \\( T_1, \\ldots, T_n \\), and \\( T_1, \\ldots, T_n \\) is an admissible domain of \\( g \\)\n\n(invar)\\text{nom} \\[ E \\vdash \\forall H'(t[x_1; T_1, \\ldots, x_n; T_n] = t'[x_1; T_1, \\ldots, x_n; T_n]) \\]\n\\[ E \\vdash \\forall H(t[t_1, \\ldots, t_n] = t'[t_1, \\ldots, t_n]), \\]\nwhere \\( t_1, \\ldots, t_n \\) are of nominal \\( H \\)-types \\( T_1, \\ldots, T_n \\)\n\n(invar)\\text{sub} \\[ E \\vdash \\forall H'(t[x_1; T_1, \\ldots, x_n; T_n] = t'[x_1; T_1, \\ldots, x_n; T_n]) \\]\n\\[ E \\vdash \\forall H(t[t_1, \\ldots, t_n] = t'[t_1, \\ldots, t_n]), \\]\nwhere \\( t_1, \\ldots, t_n \\) are of subsumptive \\( H \\)-types \\( T_1, \\ldots, T_n \\).\n\nFigure 6. Axioms and inference rules for nominal and subsumptive equational logic with subtyping over a set of equations \\( E \\). The differences between the nominal and subsumptive forms of (cong) and (invar) are highlighted in boldface.\n\nFor example, we have \\( E_{pt} \\vdash_{\\text{nom}} \\text{x(movex(CPtOrigin,1))} = 1 \\).\n\n**Theorem 2.19** (Completeness and Soundness Theorem for Equational Logic with Subtypes). Let \\( (\\Sigma, E) \\) be an equational specification, and let \\( \\forall H(t = t') \\) be an equation over \\( \\Sigma \\).\n\n(i) \\( E \\vdash_{\\text{nom}} \\forall H(t = t') \\iff E \\vdash_{\\text{nom}} \\forall H(t = t') \\).\n\n(ii) \\( E \\vdash_{\\text{ord}} \\forall H(t = t') \\iff E \\vdash_{\\text{sub}} \\forall H(t = t') \\).\n\n**Proof.** (i) \\( \\Leftarrow \\). Assume \\( E \\vdash_{\\text{nom}} \\forall H(s = s') \\) and let \\( A \\in \\text{Mod}_{\\text{nom}}(E) \\) and let \\( \\bar{a} \\) be a dynamic \\( H \\)-environment of \\( A \\). We prove \\( \\forall H(s = s') \\) is satisfied in \\( \\bar{a} \\) by induction on the length of the derivation of \\( \\forall H(s = s') \\). If \\( \\forall H(s = s') \\in E \\) this follows from the definition of \\( \\text{Mod}_{\\text{nom}}(E) \\).\n\n\\( \\Rightarrow \\). Let \\( A \\) be a model of \\( (\\Sigma, E) \\) that satisfies \\( \\forall H(t = t') \\). Then the dynamic \\( H \\)-environment \\( \\bar{a} \\) of \\( A \\) is an admissible domain for all \\( H \\) in \\( \\Sigma \\) and hence \\( E \\vdash_{\\text{nom}} \\forall H(t = t') \\).\nSuppose $\\forall H(s = s')$ is of the form $\\forall H(g(t_1, \\ldots, t_n) = g(t'_1, \\ldots, t'_n))$ and is obtained from $\\forall H(t_1 = t'_1), \\ldots, \\forall H(t_n = t'_n)$ of nominal type $T_1, \\ldots, T_n$, which is an admissible domain of $g$, by application of $(\\text{cong})_{\\text{nom}}$. By the induction hypothesis $t_i^{A}[a] = t_i'[A][a]$ for $i \\leq n$. Thus $s^{A}[a] = g^{A}[t_1^{A}[a], \\ldots, t_n^{A}[a]] = g^{A}[t'_1[A][a], \\ldots, t'_n[A][a]] = s^{A'}[a].$\n\nSuppose now that $\\forall H(s = s')$ is of the form $\\forall H(t[t_1, \\ldots, t_n] = t'[t_1, \\ldots, t_n])$ and is obtained from $\\forall H'(t[x_1:T_1, \\ldots, x_n:T_n] = t'[x_1:T_1, \\ldots, x_n:T_n])$ by an application of $(\\text{invar})_{\\text{nom}}$, where $H' = (x_1:T_1, \\ldots, x_n:T_n)$ and $t_1, \\ldots, t_n$ are nominal $H$-types $T_1, \\ldots, T_n$. Let $\\bar{b} = (t_1^{A}[a], \\ldots, t_n^{A}[a])$ and $\\bar{b}' = (t'_1[A][a], \\ldots, t'_n[A][a])$. Then $\\bar{b}$ and $\\bar{b}'$ are dynamic $H$-environments, since $A$ is nominal, and $\\bar{b} = \\bar{b}'$ by the induction hypothesis. So $s^{A}[a] = t^A[b] = t^A[b'] = s^{A'}[a].$\n\nThe verifications that $\\forall H(t = t')$ is satisfied in $\\bar{a}$ when it is obtained using $(\\text{refl})$, $(\\text{sym})$, or $(\\text{trans})$ are similar.\n\n(ii) $\\Leftarrow$. Assume now that $E \\vdash_{\\text{sub}} \\forall H(s = s')$ and let $A \\in \\text{Mod}_{\\text{ord}}(E)$ and let $\\bar{a}$ be a dynamic $H$-environment of $A$. Then the proof is similar to that above with the “nominal” concepts replaced by the corresponding “subsumptive” ones. The reason the $\\bar{b}$ and $\\bar{b}'$ obtained as above are dynamic $H'$-environments, is because in this case $A$ is order-sorted.\n\n(i) $\\Rightarrow$. We prove the contrapositive. Assume $E \\not\\vdash_{\\text{nom}} \\forall H(s = s')$. We construct a nominal model of $E$ and an $H$-environment in which $\\forall H(s = s')$ is not valid. Let $\\Theta = \\langle \\Theta_T : T \\in \\text{TYPE} \\rangle$ be the sorted binary relation on $\\text{TM}_H(H) = \\langle \\text{TM}_H(H) : T \\in \\text{TYPE} \\rangle$ defined by $\\Theta_T = \\{ \\langle t, t' \\rangle : E \\vdash_{\\text{nom}} \\forall H(t = t') \\}$. $\\Theta$ is a congruence relation by the rules $(\\text{refl})$, $(\\text{sym})$, and $(\\text{trans})$. To see that $\\Theta$ is a congruence relation, let $g \\in \\text{Op}_n$ with admissible type $T_1, \\ldots, T_n \\rightarrow T$, and suppose $t_1, \\ldots, t_n$ and $t'_1, \\ldots, t'_n$ are two sequences of well $H$-typed terms of nominal type $T_1, \\ldots, T_n$ such that $\\langle t_1, t'_1 \\rangle \\in \\Theta_{T_1}, \\ldots, \\langle t_n, t'_n \\rangle \\in \\Theta_{T_n}$. Then by definition of $\\Theta$, $E \\vdash_{\\text{nom}} \\forall H(t_1 = t'_1), \\ldots, E \\vdash_{\\text{nom}} \\forall H(t_n = t'_n)$. Thus $E \\vdash_{\\text{nom}} \\forall H(g(t_1, \\ldots, t_n) = g(t'_1, \\ldots, t'_n))$ by $(\\text{cong})_{\\text{nom}}$. So $g(t_1, \\ldots, t_n), g(t'_1, \\ldots, t'_n) \\in \\Theta_T$.\n\nThe quotient algebra $\\text{TM}_H(H)/\\Theta$ is nominal since $\\text{TM}_H(H)$ is nominal. Let $\\forall H'(t[y_1:S_1, \\ldots, y_n:S_n] = t'[y_1:S_1, \\ldots, y_n:S_n]) \\in E$, where $H' = \\langle y_1:S_1, \\ldots, y_n:S_n \\rangle$, and let the equivalence class representatives $t_1/\\Theta, \\ldots, t_n/\\Theta$ be of nominal types $S_1, \\ldots, S_n$ in $\\text{TM}_H(H)/\\Theta$. Then the terms $t_1, \\ldots, t_n$ are well $H'$-typed and of nominal $H$-type $S_1, \\ldots, S_n$ since $\\text{TM}_H(H)$ is nominal. So, by $(\\text{invar})_{\\text{nom}},$\n\n\\[\nt^{\\text{TM}_H(H)/\\Theta}[t_1/\\Theta, \\ldots, t'_n/\\Theta] = t[t_1:T_1, \\ldots, t_n:T_n]/\\Theta = t'[t_1:T_1, \\ldots, t_n:T_n]/\\Theta = t^{\\text{TM}_H(H)/\\Theta}[t_1/\\Theta, \\ldots, t_n/\\Theta].\n\\]\n\nSo $\\forall H'(t[t_1:T_1, \\ldots, t_n:T_n] = t'[t_1:T_1, \\ldots, t_n:T_n]) \\in E$ is valid in $\\text{TM}_H(H)/\\Theta$ and hence $\\text{TM}_H(H)/\\Theta$ is a nominal model of $E$.\n\nLet $H = \\langle x_1:T_1, \\ldots, x_n:T_n \\rangle$ and let $H/\\Theta = \\langle x_1/\\Theta, \\ldots, x_n/\\Theta \\rangle$ be the canonical $H$-environment of $\\text{TM}_H(H)/\\Theta$.\n\n\\[\ns^{\\text{TM}_H(H)/\\Theta}[x_1/\\Theta, \\ldots, x_n/\\Theta] = s[x_1:T_1, \\ldots, x_n:T_n]/\\Theta \\\\\n\\neq s'[x_1:T_1, \\ldots, x_n:T_n]/\\Theta \\\\\n= s^{\\text{TM}_H(H)/\\Theta}[x_1/\\Theta, \\ldots, x_n/\\Theta],\n\\]\nwhere the inequality holds by assumption. So $E \\not\\models_{\\text{Nom}} \\forall H(s = s')$.\n\n(ii) $\\Rightarrow$. Assume $E \\not\\models_{\\text{sub}} \\forall H(s = s')$. Let $\\Theta^\\circ = \\langle \\Theta_T^\\circ : T \\in \\text{TYPE} \\rangle$ be the sorted binary relation on $\\text{Tm}_E(H)^\\circ = \\langle \\text{Tm}_E(H)^\\circ_T : T \\in \\text{TYPE} \\rangle$ defined by $\\Theta_T^\\circ = \\{ (t, t') : E \\vdash_{\\text{sub}} \\forall H(t = t') \\}$. A verification that $\\forall H(s = s')$ is not valid in $\\text{Tm}_E(H)^\\circ / \\Theta^\\circ$ is obtained from the one above by making the obvious modifications.\n\nThe completeness and soundness theorem shows that the formal methods of equational logic alone are adequate for characterizing both the order-sorted and the nominal models of an equational specification (corresponding respectively to whether or not (subsumption) is admitted as a typing rule). It is well known, however, that they are not adequate for those models in which identity coincides with behavioral equivalence and hence inadequate for characterizing the correctly behaviorally subtyped models of the specification (see Section 5). A new equational logic is required with an expanded notion of consequence [3, 7, 33, 34, 35]. These ideas are developed in the next section.\n\nBefore turning to this however, we give an alternative formalization of equational consequence that will prove useful in developing the proof theory of behavioral equivalence.\n\n**Definition 2.20.** Let $E$ be a set of equations and let $\\bar{E} = \\{ \\forall H(t = t') : \\forall H(t' = t) \\in E \\}$. Let $H = [x_1: T_1, \\ldots, x_n: T_n]$ be a fixed but arbitrary type context. Define $\\equiv_E(H) = \\langle \\equiv_E(H)_T : T \\in \\text{TYPE} \\rangle$ to be the TYPE-sorted binary relation on $\\text{Tm}_E(H)$ such that, for all $H$-terms $t$ and $t'$ of nominal type $T$, $t \\equiv_E(H)_T t'$ iff there is a $\\Sigma$-term $r[z:S, x_1: T_1, \\ldots, x_n: T_n]$ of type $T$, with exactly one occurrence of a distinguished variable $z$, and an equation $\\forall K[e[y_1: S_1, \\ldots, y_m: S_m] = e'[y_1: S_1, \\ldots, y_m: S_m])$ of type $S$ in $E \\cup \\bar{E}$ such that\n\n\\[\nt = r[e[u_1, \\ldots, u_m], x_1, \\ldots, x_n] \\quad \\text{and} \\quad t' = r[e'[u_1, \\ldots, u_m], x_1, \\ldots, x_n],\n\\]\n\nwhere $u_i[x_1: T_1, \\ldots, x_n: T_n]: S_i$, for $i \\leq n$, are arbitrary $H$-terms.\n\nDefine $\\equiv_E(H)^* = \\langle \\equiv_E(H)^*_T : T \\in \\text{TYPE} \\rangle$ to be the reflexive and transitive closure of $\\equiv_E(H)$.\n\nNote that $\\equiv_E(H)^*$ is symmetric because $\\equiv_E(H)$ is obviously symmetric.\n\n**Lemma 2.21 (Alternative Formalization of Equational Deduction).** Let $(\\Sigma, E)$ be an equational specification and $\\forall H(t = t')$ be an $H$-equation of type $T$. Then\n\n\\[E \\not\\models_{\\text{Nom}} \\forall H(t = t') \\iff t \\equiv_E(H)^*_T t'.\\]\n\n**Proof.** The proof of the implication from right to left is straightforward and is omitted.\n\nFor the implication in the opposite direction we show that $t \\equiv_E(H)^*_T t'$ for every equation $\\forall H(t = t')$ of type $T$ included in $E$, and that $\\equiv_E(H)^*$ is closed under the rules of equational logic in the sense that the set of equations $\\forall H(t = t')$ such that $t \\equiv_E(H)^*_T t'$, where $T$ is the type of $\\forall H(t = t')$, is closed under equational deduction. Consider any equation $\\forall H(e[x_1: T_1, \\ldots, x_m: T_m] = e'[x_1: T_1, \\ldots, x_m: T_m])$ in $E$ and let $S$ be its type. Taking $r[z:S, x_1: T_1, \\ldots, x_m: T_m]$ to be $z:S$ and $u_i[x_1: T_1, \\ldots, x_n: T_n]$ to be $x_i:T_i$ for each $i \\leq n$ we get\n\n\\[r[e[u_1, \\ldots, u_m], x_1, \\ldots, x_n] = e' \\quad \\text{and} \\quad r[e'[u_1, \\ldots, u_m], x_1, \\ldots, x_n] = e'.\\]\n\nSo by definition $e \\equiv_E(H)_S e'$ and hence $e \\equiv_E(H)^*_S e'$.\nThe relation \\( \\equiv_E(H)^* \\) is closed under the rules (refl), (sym), and (trans) by construction. We now show it is also closed under \\((\\text{cons})_{\\text{Nom}}\\). For this purpose we first show that the closure of \\( \\equiv_E(H) \\) under \\((\\text{cons})_{\\text{Nom}}\\) is included in \\( \\equiv_E(H)^* \\). Let \\( g \\in \\text{Op}_n \\) and let \\( T_1, \\ldots, T_n \\to T \\) be an admissible type of \\( g \\). Suppose \\( t_i \\equiv_E(H)_{T_i} t'_i \\) for \\( i \\leq n \\). To show \\( g(t_1, \\ldots, t_n) \\equiv_E(H)^*_T g(t'_1, \\ldots, t'_n) \\) it suffices to show that\n\n\\[\n(1) \\quad g(t'_1, \\ldots, t'_i-1, t_i, t_i+1, \\ldots, t_n) \\equiv_E(H)_T g(t'_1, \\ldots, t'_i-1, t'_i, t_{i+1}, \\ldots, t_n)\n\\]\n\nfor each \\( i \\leq n \\). There is an equation \\( \\forall K(e[y_1:S_1, \\ldots, y_m:S_m] = e'[y_1:S_1, \\ldots, y_m:S_m]) \\in E \\cup \\bar{E} \\) of type \\( S \\) such that \\( t_i = r[e[\\bar{u}], \\bar{x}] \\) and \\( t'_i = r[e'[\\bar{u}], \\bar{x}] \\), where \\( \\bar{u} = u_1, \\ldots, u_m \\) and \\( \\bar{x} = x_1, \\ldots, x_n \\). Thus\n\n\\[\ng(t'_1, \\ldots, t'_i-1, t_i, t_{i+1}, \\ldots, t_n) = g(t'_1, \\ldots, t'_i-1, r[e[\\bar{u}], \\bar{x}], t_{i+1}, \\ldots, t_n),\n\\]\n\n\\[\ng(t'_1, \\ldots, t'_i-1, t'_i, t_{i+1}, \\ldots, t_n) = g(t'_1, \\ldots, t'_i-1, r[e'[\\bar{u}], \\bar{x}], t_{i+1}, \\ldots, t_n).\n\\]\n\nSo \\( g(t'_1, \\ldots, t'_i-1, t_i, t_{i+1}, \\ldots, t_n) = s[e[\\bar{u}], \\bar{x}] \\) and \\( g(t'_1, \\ldots, t'_i-1, t'_i, t_{i+1}, \\ldots, t_n) = s[e'[\\bar{u}], \\bar{x}] \\), where\n\n\\[\ns[z:T_1, x_1:T_1, \\ldots, x_n:T_n] = g(t'_0[\\bar{x}], \\ldots, t'_i-1[\\bar{x}], z, t_{i+1}[\\bar{x}], \\ldots, t_n[\\bar{x}]).\n\\]\n\nSo (1) holds.\n\nSuppose now that \\( g \\in \\text{Op}_n \\), \\( T_1, \\ldots, T_n \\to T \\) is an admissible type of \\( g \\), and for each \\( i \\leq n \\), \\( t_i \\equiv_E(H)_{T_i} t'_i \\). Then for each \\( i \\leq n \\) there exist terms \\( s_1^i, \\ldots, s_m^i \\) such that\n\n\\[\nt_i = s_1^i \\equiv_E(H)_{T_i} s_2^i \\equiv_E(H)_{T_i} \\cdots \\equiv_E(H)_{T_i} s_{m_i}^i \\equiv_E(H)_{T_i} s_m^i = t'_i\n\\]\n\n(note that he length of the sequences \\( s_1^i, \\ldots, s_m^i \\) can be taken to be the same for all \\( i \\) because \\( \\equiv_E(H)_{T_i} \\) is reflexive). By the result just established, \\( g(s_1^1, \\ldots, s_m^1) \\equiv_E(H)^*_{T_1} \\cdots \\equiv_E(H)^*_{T_n} g(s_1^m, \\ldots, s_m^m) \\). So by transitivity of \\( \\equiv_E(H)^*_{T_i} \\), \\( g(t_1, \\ldots, t_n) \\equiv_E(H)_{T_i} g(t'_1, \\ldots, t'_n) \\), as desired.\n\nTo show that \\( \\equiv_E(H)^* \\) is closed under \\((\\text{invar})_{\\text{Nom}}\\), we first show that \\( \\equiv_E(H) \\) is closed under \\((\\text{invar})_{\\text{Nom}}\\). Suppose \\( t[z_1:R_1, \\ldots, z_p:R_p] \\equiv_E(H)^*_R t'[z_1:R_1, \\ldots, z_p:R_p] \\) for some type context \\( H' \\), and suppose \\( w_1, \\ldots, w_p \\) are terms of nominal \\( H \\)-type \\( R_1, \\ldots, R_p \\). We must show that \\( t[w_1, \\ldots, w_p] \\equiv_E(H)_{R} t'[w_1, \\ldots, w_p] \\). Now, by definition of \\( \\equiv_E(H)_{R} \\), there is a term \\( r[z:S, z_1:R_1, \\ldots, z_p:R_p] \\) and an equation \\( \\forall K(e[y_1:S_1, \\ldots, y_m:S_m] = e'[y_1:S_1, \\ldots, y_m:S_m]) \\) in \\( E \\cup \\bar{E} \\) of type \\( S \\) such that\n\n\\[\nt = r[e[u_1[z], \\ldots, u_m[z]], z] \\quad \\text{and} \\quad t' = r[e'[u_1[z], \\ldots, u_m[z]], z],\n\\]\n\nwhere \\( z = z_1, \\ldots, z_p \\). Now define \\( v_i[x_1, \\ldots, x_n] = u_i[w_1[x_1, \\ldots, x_n], \\ldots, w_p[x_1, \\ldots, x_n]] \\) for every \\( i \\leq m \\), and consider the term\n\n\\[\ns[z:S, x_1, \\ldots, x_n] = r[z:S, w_1[x_1, \\ldots, x_n], \\ldots, w_p[x_1, \\ldots, x_n]].\n\\]\n\nThus\n\n\\[\nt[w_1, \\ldots, w_p] = s[e[v_1, \\ldots, v_m], x_1, \\ldots, x_n] \\quad \\text{and} \\quad t'[w_1, \\ldots, w_p] = s[e'[v_1, \\ldots, v_m], x_1, \\ldots, x_n],\n\\]\n\nso by definition of \\( \\equiv_E(H)_{R} \\), \\( t[w_1, \\ldots, w_p] \\equiv_E(H)_{R} t'[w_1, \\ldots, w_p] \\).\n\nThe closure of \\( \\equiv_E(H)^* \\) under \\((\\text{invar})_{\\text{Nom}}\\) is an immediate consequence of the closure of \\( \\equiv_E(H) \\). \\( \\square \\)\n3. The Logic of Behavioral Equivalence\n\nThe notion of behavioral equivalence is simple in concept: two hidden objects of the same type are behaviorally equivalent if any procedure whose parameter is of this type returns the same visible result when executed with either of the two objects as input. The notion arises from the alternative view of a data structure as a transition system in which the hidden objects represent states of the system and the methods that are not attributes induce transitions between states. (The term “constructors” which we introduced earlier for such methods is appropriate for the algebraic but not for the transition-system paradigm.) At a more abstract level the transition-system paradigm can be characterized as coalgebraic [19, 20, 35] with coinduction as the basis of the corresponding proof theory. (This is in contrast to the algebraic paradigm where induction forms the basis of the proof theory.) Behavioral equivalence has proved to be a useful device for importing transition-system and coalgebraic methods into the algebraic paradigm, and has served as the basis of a formal theory of subtyping in our earlier work [22, 23].\n\nIn the context of logic the basic idea is an old one, going back to the beginnings of algebraic logic and the Lindenbaum-Tarski process [38]. More recently it has been the principal feature of abstract algebraic logic (which can also be viewed as coalgebraic logic; see for instance [4, 8, 30]). In computer science it has also been around for a long time; see [22] for a systematic development of the non-proof-theoretical part of the theory in the context of correct subtyping. A more extensive development that includes parts of the proof theory but not subtyping can be found in the series of papers on hidden algebras; see [15, 16] and the many papers referenced there.\n\nTo reason effectively about behavioral equivalence and subtyping, we introduce the concept of a behavioral consequence—a relation between sets of equations and equations rather than pairs of hidden objects. The proof theory of behavioral consequence is based on coinduction, and various methods of applying coinduction in a reasonably efficient way have been investigated in the literature (see for example [15, 33, 34]). We consider one such method here that uses the notion of a local context. But verifying behavioral consequence can be a laborious process under the best of circumstances. One of the main things we prove in this section is the closure of behavioral consequence under nominal equational consequence; i.e., that any equation that is nominally provable from a set of behavioral consequences is itself a behavioral consequence. This turns out to be an effective method for proving correct behavioral subtyping in many cases. It works when all the equations associated with a given set of coercion functions can be proved by nominal equational logic from just a few judiciously chosen ones, which then are proved to be behavioral consequences directly by coinduction. An example in this kind is considered in some detail in the sequel.\n\nAs was alluded to in the previous paragraph, the most important application of the concept of behavioral consequence in this work is to the specification of coercion functions; correct behavioral subtyping results when the equations for a set of coercion functions are all behavioral consequences. In short, coinduction gives a sound proof theory for behavioral consequence, and hence for correct behavioral subtyping via coercion. This is treated in detail in the next section.\nWe begin by giving the definition of behavioral equivalence; it requires an auxiliary notion, which following Goguen and Malcolm [15] we call context (not to be confused with a type-context).\n\n**Definition 3.1 (Context).** Let $\\Sigma$ be a hidden signature and $T$ a type. By a $(\\Sigma, T)$-context, we mean a $\\Sigma$-term of visible type of the form\n\n\\[ r[z:T, x_1:S_1, \\ldots, x_m:S_m], \\]\n\nwhere $z$, called the designated variable of the $S$-context, is distinct from the $y_1, \\ldots, y_m$ and has just one occurrence in $r$.\n\nSubtyping does not play a role in the definition of a $(\\Sigma, T)$-context. Also, we often call a $(\\Sigma, T)$-context a “$T$-context” when the signature $\\Sigma$ is understood.\n\n**Definition 3.2 (Behavioral Equivalence).** Let $\\Sigma$ be a signature, $A$ a $\\Sigma$-algebra, and $T$ a type. Elements $a$ and $a'$ of $A$ of type $T$ are said to be behaviorally equivalent if, for each $T$-context and all $(b_1, \\ldots, b_m) \\in A_{S_1} \\times \\cdots \\times A_{S_m}$,\n\n\\[ r^A[a, b_1, \\ldots, b_m] = r^A[a', b_1, \\ldots, b_m]. \\]\n\nThe TYPE-sorted behavioral equivalence relation $BE(A) = \\langle BE_T(A) : T \\in \\text{TYPE} \\rangle$ on $A$ is defined in the obvious way, namely, $BE_T(A)$ is the set of all behaviorally equivalent pairs of elements of $A_T$.\n\nWe will write “$BE$” for “$BE(A)$” when the algebra $A$ is clear from context. Note that, by taking $r$ to be the variable $z$ itself, we see that two visible data elements are behaviorally equivalent iff they are identical.\n\nA context is the formal representation of a procedure that takes an object $a$ of hidden type $T$, together with the parameters $b_1, \\ldots, b_m$, as input and, upon execution, outputs the visible data element $r^A[a, b_1, \\ldots, b_m]$. Intuitively, two objects are behaviorally equivalent if they give the same output for all procedures and all choices of parameters.\\(^4\\)\n\nIn its most primitive form coinduction amounts to verifying the equalities (3) for all contexts $r$, a potentially infinite set. Many of the methods for effectively managing coinduction amount to coming up with a relatively small set of contexts that can be used in place of all of them. We consider one such set now, what Goguen and Malcom call local contexts [15]. Intuitively, a local context is one that only applies one attribute to the distinguished context variable.\n\n**Definition 3.3.** A $(\\Sigma, T)$-context $r[z:T, y_1:S_1, \\ldots, y_m:S_m]$ is local if it is of the form\n\n\\[ r[z:T, y_1:S_1, \\ldots, y_m:S_m] = g(h[z, y_1, \\ldots, y_m], y_1, \\ldots, y_m), \\]\n\nwhere $g$ is an attribute and $h$ is a term containing the single occurrence of $z$ in $r$ whose only non-constant operation symbols are constructors.\n\n\\(^4\\)If the system of parameters is held fixed, we get a related notion of behavioral equivalence localized to the environment. This local notion of behavioral equivalence relates environments rather than individual objects and is the one used in our earlier work on the model theory of correct behavioral subtyping [21, 23]; see Appendix A.\nLemma 3.4. Let $A$ be a $\\Sigma$-algebra and $T$ a hidden type. Let $a, a' \\in A_T$. Then $a \\models_{BE} a'$ iff for every local $T$-context $r[z; T, y_1; S_1, \\ldots, y_m; S_m]$ and all $(b_1, \\ldots, b_m) \\in A_{S_1} \\times \\cdots \\times A_{S_m}$,\n\\begin{equation}\n r^A[a, b_1, \\ldots, b_m] = r^A[a', b_1, \\ldots, b_m].\n\\end{equation}\n\nProof. The implication from right to left is trivial, since every local context is a priori a context. For the opposite direction, assume that every local context with arbitrary choice of parameters returns the same element when evaluated with input $a$ and $a'$. Let $r[z; T, y_1; S_1, \\ldots, y_m; S_m]$ be an arbitrary $T$-context. Since $r$ is visible and $z$ is hidden, $r$ must contain at least one operation symbol, and its leading operation symbol must be visible or an attribute. Let $r'[z, y_1, \\ldots, y_m]$ be the smallest subterm of $r$ that includes the lone occurrence of $z$, and whose leading operation symbol, say $g$, is visible or an attribute. Since $z$ is hidden, $g$ must be an attribute, and $r'$ must be of the form $g[h(z, \\bar{y}), \\bar{y}]$, where $h$ is a term whose only non-constant operation symbols are constructors; i.e., $r'$ is a local context. Moreover, $r$ is of the form $q[r'[z, \\bar{y}], \\bar{y}]$ for some $\\Sigma$-term $q[w, \\bar{y}]$. By assumption, for all $\\bar{b} \\in A_{S_1} \\times \\cdots \\times A_{S_m}$, \n\\begin{equation}\n r^A[a, \\bar{b}] = r^A[a', \\bar{b}].\n\\end{equation}\nThus $r^A[a, \\bar{b}] = q^A[r^A[a, \\bar{b}], \\bar{b}] = q^A[r^A[a', \\bar{b}], \\bar{b}] = r^A[a', \\bar{b}]$. Hence $a \\models_{BE_T} a'$.\n\nDefinition 3.5 (Behavioral Consequence). Let $\\langle \\Sigma, E \\rangle$ be a hidden equational specification and $H$ a type context. An $H$-equation $\\forall H(t = t')$ over $\\Sigma$ is a behavioral consequence of $E$, in symbols $E \\models_{BEH} \\forall H(t = t')$, if, for every $A \\in \\text{Mod}_{\\text{Nom}}(E)$ and every $H$-environment $\\bar{a}$ of $A$, $t^A[\\bar{a}] \\models_{BE_T} t^A[\\bar{a}]$, where $T$ is the type of $\\forall H(t = t')$.\n\nIt follows immediately from the definition that $\\models_{BEH}$ is monotonic, i.e., If $E \\models_{BEH} F$, then $E' \\models_{BEH} F$ for every set $E'$ of equations such that $E' \\supseteq E$.\n\nDefinition 3.6 (Behavioral Provability). Let $\\langle \\Sigma, E \\rangle$ be a hidden equational specification, and $H$ a type context. An $H$-equation $\\forall H(t = t')$ of type $T$ over $\\Sigma$ is behaviorally provable from $E$, in symbols $E \\vdash_{BEH} \\forall H(t = t')$, if, for every type context $K = \\langle y_1; S_1, \\ldots, y_m; S_m \\rangle$ disjoint from $H$ and every $T$-context $r[z; T, y_1; S_1, \\ldots, y_m; S_m]$, \n\\begin{equation}\n E \\vdash_{\\text{Nom}} \\forall(H \\cup K)(r[t, y_1, \\ldots, y_m] = r'[t', y_1, \\ldots, y_m]).\n\\end{equation}\n\nThe following completeness and soundness theorem is an easy corollary of the definitions of $\\models_{BEH}$ and $\\vdash_{BEH}$.\n\nTheorem 3.7 (Completeness and Soundness Theorem for Behavioral Logic). Let $\\langle \\Sigma, E \\rangle$ be a hidden equational specification and $H$ a type context. Then, for every $H$-equation $\\forall H(t = t')$,\n\\begin{equation}\n E \\models_{BEH} \\forall H(t = t') \\iff E \\vdash_{BEH} \\forall H(t = t').\n\\end{equation}\nProof.\n\n\\( E \\models \\forall H(t = t') \\)\n\niff (by definition of \\( \\models \\))\n\nfor every \\( A \\in \\text{Mod}_\\text{nom}(E) \\) and every \\( H \\)-environment \\( \\bar{a} \\),\n\n\\( t^A[\\bar{a}] BE t'^A[\\bar{a}] \\)\n\niff (by definition of \\( BE \\))\n\nfor every \\( A \\in \\text{Mod}_\\text{nom}(E) \\), every \\( H \\)-environment \\( \\bar{a} \\),\n\nevery type context \\( K \\), every \\( T \\)-context \\( r[z, \\bar{y}] \\), and every \\( K \\)-environment \\( \\bar{b} \\),\n\n\\( r^A[\\bar{a}][\\bar{b}] = r'^A[\\bar{a}][\\bar{b}] \\)\n\niff (by definition of \\( \\models \\))\n\nfor every type context \\( K \\) and every \\( T \\)-context \\( r[z, \\bar{y}] \\),\n\n\\( E \\models \\forall(H \\cup K)(r[t, y_1, \\ldots, y_m] = r'[t', y_1, \\ldots, y_m]) \\)\n\niff (by completeness and soundness theorem of equational logic)\n\nfor every type context \\( K \\) and every \\( T \\)-context \\( r[z, \\bar{y}] \\),\n\n\\( E \\vdash \\forall(H \\cup K)(r[t, y_1, \\ldots, y_m] = r'[t', y_1, \\ldots, y_m]) \\)\n\niff (by definition of \\( \\models \\))\n\n\\( E \\models \\forall \\forall H(t = t') \\).\n\n\\[ \\square \\]\n\nThus, in the sequel we use \\( \\models \\) and \\( \\vdash \\) interchangeably, often referring to the latter as “behavioral consequence”.\n\n**Corollary 3.8.** Let \\( \\langle \\Sigma, E \\rangle \\) be a hidden equational specification and \\( \\forall H(t = t') \\) an equation over \\( \\Sigma \\). Then \\( E \\models \\forall \\forall H(t = t') \\) iff, for every type context \\( K = (y_1: S_1, \\ldots, y_m: S_m) \\) disjoint from \\( H \\) and every \\( T \\)-context \\( r[z: T, y_1: S_1, \\ldots, y_m: S_m] \\),\n\n\\( E \\models \\forall(H \\cup K)(r[t, y_1, \\ldots, y_m] = r'[t', y_1, \\ldots, y_m]). \\)\n\n**Proof.** It suffices to observe that, if \\( E \\models \\forall H(t = t') \\) is of visible type, all the equivalences of the preceding proof continue to hold when \\( r \\) is restricted to local contexts. In this case the second equivalence is justified by Lem. 3.4. \\( \\square \\)\n\nLocal contexts can be an effective tool for verifying behavioral provability and hence behavioral consequence in particular cases.\n\n**Example 3.9.** Each of the three equations\n\n\\[\n\\begin{align*}\n\\text{movex(movex}(p, i), j) & = \\text{movex}(p, \\text{add}(i, j)) \\\\\n\\text{movey(movey}(p, i), j) & = \\text{movey}(p, \\text{add}(i, j)) \\\\\n\\text{movex(movex}(p, i), j) & = \\text{movey(movex}(p, j), i)\n\\end{align*}\n\\]\n\nis behaviorally provable from \\( E_{cp} \\) and hence also from \\( E_{cpt} \\) by the monotonicity of \\( \\models \\). To verify this for the first equation it suffices by Cor. 3.8 to show both of the following.\n\n(6) \\( E \\models \\forall x(h[\\text{movex(movex}(p, i), j), y_1, \\ldots, y_m]) = x(h[\\text{movex}(p, \\text{add}(i, j)), y_1, \\ldots, y_m]) \\),\n\n(7) \\( E \\models \\forall y(h[\\text{movex(movex}(p, i), j), y_1, \\ldots, y_m]) = y(h[\\text{movex}(p, \\text{add}(i, j)), y_1, \\ldots, y_m]) \\)\n\nwith\n\n\\[\nh(z, y_1, \\ldots, y_m) = f_m(\\cdots(f_2(f_1(z, y_1), y_2)\\cdots), y_m).\n\\]\nwhere $f_1, \\ldots, f_m$ is any sequence of $\\text{move}x$’s and $\\text{move}y$’s. We prove (6) and (7) hold by induction on the structure of $h$. If $m = 0$, i.e., $h$ is a variable, then the two equations take the form\n\n$$E \\vdash_{\\text{nom}} x(\\text{move}x(\\text{move}x(p, i), j)) = x(\\text{move}x(p, \\text{add}(i, j))),$$\n$$E \\vdash_{\\text{nom}} y(\\text{move}y(\\text{move}x(p, i), j)) = y(\\text{move}x(p, \\text{add}(i, j))).$$\n\nWe verify the first of them and leave the second to the reader.\n\n$$x(\\text{move}x(\\text{move}x(p, i), j)) = \\text{add}(x(\\text{move}x(p, i), j), \\text{by axiom} (x-\\text{move}x) \\text{ of } E_{\\text{pt}})$$\n$$= \\text{add}(\\text{add}(x(p), i), j), \\text{by axiom} (x-\\text{move}x) \\text{ of } E_{\\text{pt}}$$\n$$= \\text{add}(x(p), \\text{add}(i, j)), \\text{by axioms for integers}$$\n$$-x(\\text{move}x(p, \\text{add}(i, j))), \\text{by axiom} (x-\\text{move}x) \\text{ of } E_{\\text{pt}}.$$\n\nAssume $m > 0$, and consider the case $f_m = \\text{move}y$. Let\n\n$$h'(z, y_1, \\ldots, y_{m-1}) = f_{m-1}(\\cdots(f_2(f_1(z, y_1), y_2)\\cdots), y_{m-1}),$$\n\nso that $h(z, y_1, \\ldots, y_m) = \\text{move}y(h'(z, y_1, \\ldots, y_{m-1}, y_m)).$ Then (6) and (7) become\n\n$$E \\vdash_{\\text{nom}} x(\\text{move}y(h'\\text{move}x(\\text{move}x(p, i), j), y_1, \\ldots, y_{m-1}, y_m))$$\n$$= x(\\text{move}y(h'\\text{move}x(p, \\text{add}(i, j)), y_1, \\ldots, y_{m-1}, y_m),$$\n\n$$E \\vdash_{\\text{nom}} y(\\text{move}y(h'\\text{move}x(\\text{move}x(p, i), j), y_1, \\ldots, y_{m-1}, y_m))$$\n$$= y(\\text{move}y(h'\\text{move}x(p, \\text{add}(i, j)), y_1, \\ldots, y_{m-1}, y_m)).$$\n\nWe verify the first of them and again leave the second to the reader.\n\n$$x(\\text{move}y(h'\\text{move}x(\\text{move}x(p, i), j), y_1, \\ldots, y_{m-1}, y_m)$$\n$$= x(\\text{move}y(h'(\\text{move}x(p, i), j), y_1, \\ldots, y_{m-1}, y_m), \\text{by axiom} (x-\\text{move}y) \\text{ of } E_{\\text{pt}}$$\n$$= x(h'(\\text{move}x(p, \\text{add}(i, j)), y_1, \\ldots, y_{m-1}, y_m), \\text{by induction hypothesis}$$\n$$= x(\\text{move}y(h'(\\text{move}x(p, \\text{add}(i, j)), y_1, \\ldots, y_{m-1}, y_m)), \\text{by axiom} (x-\\text{move}y) \\text{ of } E_{\\text{pt}}.$$\n\nThis verifies that the equation $\\text{move}x(\\text{move}x(p, i), j) = \\text{move}x(p, \\text{add}(i, j))$ is a formal behavioral equivalence over $E_{\\text{pt}}$. The formal behavioral equivalence of $\\text{move}y(p, i, j) = \\text{move}y(p, \\text{add}(i, j))$ and $\\text{move}y(p, i, j) = \\text{move}y(p, j, i)$ over $E_{\\text{pt}}$ can be established in a similar way.\n\nThe next theorem gives an alternate proof-theoretic characterization that will be used to prove the closure of behavioral consequence under nominal equational consequence. Simply put it says that an equation $\\forall H(t = t')$ is a behavioral consequence of $E$ iff no visible equation is nominally provable from $E$ together with $\\forall H(t = t')$ that is not provable from $E$ alone.\n\n**Theorem 3.10.** Let $(\\Sigma, E)$ be a hidden equational specification and let $F$ be a set of $\\Sigma$-equations. Then the following are equivalent.\n\n(i) For every $\\forall H(t = t') \\in F$, $E \\vdash_{\\text{beh}} \\forall H(t = t')$. \n\nThe set of $\\Sigma$-equations $F$ is a conservative extension of $E$.\n(ii) For all equations \\( \\forall K(s = s') \\) of visible type,\n\\[\nE \\cup F \\vdash_{\\text{nom}} \\forall K(s = s') \\quad \\text{implies} \\quad E \\vdash_{\\text{nom}} \\forall K(s = s').\n\\]\n\nProof. We first prove that (ii) implies (i). So assume (ii) holds and let \\( \\forall H(t = t') \\) be an equation in \\( F \\). We show that \\( E \\vdash_{\\text{beh}} \\forall H(t = t') \\) by verifying the condition of Defn. 3.6. Let \\( K = \\langle y_1: S_1, \\ldots, y_m: S_m \\rangle \\) be a type context disjoint from \\( H \\), and let \\( r[z:T, y_1:S_1, \\ldots, y_m:S_m] \\) be a \\( T \\)-context, where \\( T \\) is the type of \\( \\forall H(t = t') \\). By \\((\\text{cong})_{\\text{nom}}\\),\n\\[\nE \\cup \\{ \\forall H(t = t') \\} \\vdash_{\\text{nom}} \\forall (H \\cup K)(r[t, y_1, \\ldots, y_m] = r[t', y_1, \\ldots, y_m]).\n\\]\nThus \\( E \\cup F \\vdash_{\\text{nom}} \\forall (H \\cup K)(r[t, y_1, \\ldots, y_m] = r[t', y_1, \\ldots, y_m]) \\), and hence by (ii),\n\\[\nE \\vdash_{\\text{nom}} \\forall (H \\cup K)(r[t, y_1, \\ldots, y_m] = r[t', y_1, \\ldots, y_m]).\n\\]\nSo, by Defn. 3.6, \\( E \\vdash_{\\text{beh}} \\forall H(t = t') \\) for each \\( \\forall H(t = t') \\in F \\), i.e., (i) holds.\n\nNow assume (i) holds. Let \\( \\forall K(s = s') \\) be an equation of visible type \\( V \\) such that \\( E \\cup F \\vdash_{\\text{nom}} \\forall K(s = s') \\). We can assume without loss of generality that \\( K = \\langle y_1: S_1, \\ldots, y_m: S_m \\rangle \\) is disjoint from \\( H = \\langle x_1:T_1, \\ldots, x_m:T_m \\rangle \\). By Lem. 2.21, \\( s \\equiv_{E \\cup F}(K)_V s' \\). Thus there is a sequence \\( s_1, \\ldots, s_n \\) of \\( K \\)-terms of type \\( V \\) such that\n\\[\ns = s_1 = \\equiv_{E \\cup F}(K)_V s_2 = \\equiv_{E \\cup F}(K)_V \\cdots = \\equiv_{E \\cup F}(K)_V s_{n-1} = \\equiv_{E \\cup F}(K)_V s_n = s'.\n\\]\nFor each \\( i < n \\) we have either \\( s_i = \\equiv_{E(K)_V} s_{i+1} \\) or\n\\[\ns_i = \\equiv_{\\{\\forall H(t = t')\\}(K)_V} s_{i+1} \\quad \\text{for some} \\quad \\forall H(t[x_1, \\ldots, x_n] = t'[x_1, \\ldots, x_n]) \\in F.\n\\]\nIn the latter case, by definition of \\( \\equiv_{\\{\\forall H(t = t')\\}(K)_V} \\), there is a term \\( r[z:T, y_1, \\ldots, y_m] \\) and \\( K \\)-terms \\( u_1, \\ldots, u_n \\) such that either\n\\[\ns_i = r[t[u_1, \\ldots, u_n], y_1, \\ldots, y_m] \\quad \\text{and} \\quad s_{i+1} = r'[t'[u_1, \\ldots, u_n], y_1, \\ldots, y_m],\n\\]\nor the same equalities hold with the “\\( t \\)” and “\\( t' \\)” interchanged. \\( r[z:T, y_1, \\ldots, y_m] \\) is of the same visible type \\( V \\) as all the \\( s_j \\) and hence a \\( T \\)-context. So, because of the assumption (i), we have by Defn. 3.6 that\n\\[\nE \\vdash_{\\text{nom}} \\forall (H \\cup K)(r[t[x_1, \\ldots, x_n], y_1, \\ldots, y_m] = r[t'[x_1, \\ldots, x_n], y_1, \\ldots, y_m]).\n\\]\nHence \\( E \\vdash_{\\text{nom}} \\forall K(s_i = s_{i-1}) \\) by an application of \\((\\text{invar})_{\\text{nom}}\\). So in fact we have \\( s_i = \\equiv_{E(K)_V} s_{i+1} \\) for each \\( i \\) such that (8) holds. Thus \\( s \\equiv_{E(K)_V} s' \\), and hence \\( E \\vdash_{\\text{nom}} \\forall K(s = s') \\) by Lem. 2.21. We conclude that \\( E \\vdash_{\\text{beh}} F \\), and hence that (ii) holds.\n\n\\( \\square \\)\n\nCorollary 3.11 (Closure of Behavioral Consequence under Equational Consequence). Let \\( \\langle \\Sigma, E \\rangle \\) be a specification and let \\( F \\cup \\{ \\forall H(t = t') \\} \\) be a set of \\( \\Sigma \\)-equations. If \\( E \\vdash_{\\text{beh}} F \\) and \\( E \\cup F \\vdash_{\\text{nom}} \\forall H(t = t') \\), then \\( E \\vdash_{\\text{beh}} \\forall H(t = t') \\).\n\nProof. Assume \\( E \\vdash_{\\text{beh}} F \\) and \\( E \\cup F \\vdash_{\\text{nom}} \\forall H(t = t') \\). In order to show that \\( E \\vdash_{\\text{beh}} \\forall H(t = t') \\) it suffices by Thm. 3.10 to show that, for every equation \\( \\forall K(s = s') \\) of visible type,\n\\[\nE \\cup \\{ \\forall H(t = t') \\} \\vdash_{\\text{nom}} \\forall K(s = s') \\quad \\text{implies} \\quad E \\vdash_{\\text{beh}} \\forall K(s = s').\n\\]\nAssume \\( E \\cup \\{ \\forall H(t = t') \\} \\vdash_{\\text{nom}} \\forall K(s = s') \\). Then, since \\( E \\cup F \\vdash_{\\text{nom}} \\forall H(t = t') \\), we have \\( E \\cup F \\vdash_{\\text{nom}} \\forall K(s = s') \\) by the transitivity of \\( \\vdash_{\\text{nom}} \\). Thus, since \\( E \\vdash_{\\text{beh}} F \\) by assumption, we have by Thm. 3.10 that \\( E \\vdash_{\\text{nom}} \\forall K(s = s') \\). Hence \\( E \\vdash_{\\text{beh}} \\forall H(t = t') \\). \\( \\square \\)\nExample 3.12. Let $F_3$ be the set of the three equations of Example 3.9. We showed in example 3.9 that $E_{pt} \\vdash_{\\text{BEH}} F_3$ and $E_{cpt} \\vdash_{\\text{BEH}} F_3$. Hence any equation nominally provable from $E_{pt} \\cup F_3$ is a behavioral consequence of $E_{pt}$, and the same is true with “$E_{pt}$” replaced by “$E_{cpt}$”. This observation will prove to be useful in the next section in proving that $(\\Sigma_{pt}, E_{cpt})$ is correctly behaviorally subtyped. □\n\nAs another immediate corollary of Theorem 3.10 we get that the behavioral consequence relation is coinductive in the sense that its complement is inductive (relative to the complement of the of the visible equational specification).\n\nCorollary 3.13. Let $(\\Sigma, E)$ be an equational specification. Then, for every $\\Sigma$-equation $\\forall H(t = t')$, $E \\not\\vdash_{\\text{BEH}} \\forall H(t = t')$ iff there exists a visible equation $\\forall K(s = s')$ such that $E \\cup \\{\\forall H(t = t')\\} \\vdash_{\\text{NOM}} \\forall K(s = s')$ and $E \\not\\vdash_{\\text{NOM}} \\forall K(s = s')$. □\n\nNote that if $\\vdash_{\\text{NOM}}$ is recursively enumerable (RE), in particular, if $E$ is finite, then $\\vdash_{\\text{BEH}}$ is at level $\\prod_2^0$ in the arithmetical hierarchy. It is shown in [6] that there are finite equational specifications such that $\\vdash_{\\text{BEH}}$ is $\\prod_2^0$-complete. But note also that, if the visible part of $\\vdash_{\\text{NOM}}$ is recursive, then $\\vdash_{\\text{BEH}}$ is co-RE.\n\nIt will be useful when studying the role of coercion in verifying correct behavioral subtyping to have an analogue for behavioral consequence of the behavioral equivalence relation between the elements of an $\\Sigma$-algebra.\n\nDefinition 3.14 (Formal Behavioral Equivalence Relation). Let $(\\Sigma, E)$ be an equational specification and let $A$ be a $\\Sigma$-algebra. By the formal behavioral equivalence relation over $E$ on $A$ we mean the sorted binary relation\n\n$$\\mathcal{FB}(E, A) = (\\mathcal{FB}(E, A)_T : T \\in \\text{TYPE}),$$\n\nwhere, for each type $T$, $\\mathcal{FB}(E, A)_T$ is the set of all pairs $(t^A[a], t'^A[\\bar{a}])$ such that $H$ is a type context, $a$ is an $H$-environment in $A$, and $\\forall H(t = t')$ is an equation of type $T$ such that $E \\vdash_{\\text{BEH}} \\forall H(t = t')$. □\n\nAs in the case of behavioral equivalence we write “$\\mathcal{FB}(E)$” in place of “$\\mathcal{FB}(E, A)$” when the algebra $A$ is understood.\n\nAs an immediate consequence of the definition we have that, for every model $A$ of $E$, $\\mathcal{FB}(E, A) \\subseteq \\mathcal{BE}(A)$. It is easy to find examples where the inclusion is proper.\n\n4. Equational Specifications with Coercions\n\nIn this section we define coercion systems and relate them to specifications. Coercions are specified by their actions on variables, and thus are an effective way to equationally define coercion functions. The next section will show that a specification with coercions automatically has correct behavioral subtyping.\n\nLet $\\Sigma$ be a signature with subtyping. By a pre-coercion system for $\\Sigma$ we mean a sorted set of $\\Sigma$-terms $\\{c_{S,T}[x_S:S] : S, T \\in \\text{TYPE}, S \\leq T, \\text{ and } \\Sigma; <x_S:S> \\vdash c_{S,T}[x_S:S]:T\\}$ such that for each $T \\in \\text{VIS}$, $c_{T,T}[x_T:T]$ is lexically equal to $x_T$. For brevity we usually write $\\{c_{S,T}\\}$ for a pre-coercion system.\nExample 4.1. We define a pre-coercion system for $\\Sigma_{pt}, C_{pt} = \\{c_{S,T}\\}$, as follows.\n\n\\[\n\\begin{align*}\n&c_{\\text{int, int}}[x_{\\text{int}}:\\text{int}] = x_{\\text{int}} \\\\\n&c_{\\text{pt, pt}}[x_{\\text{pt}}, y_{\\text{pt}}] = \\text{movex}(\\text{movey}(\\text{PtOrigin}, x(y_{\\text{pt}}})), y(x_{\\text{pt}})) \\\\\n&c_{\\text{Cpt, pt}}[x_{\\text{Cpt}}, y_{\\text{pt}}] = \\text{movex}(\\text{movey}(\\text{PtOrigin}, x(x_{\\text{Cpt}})), y(x_{\\text{Cpt}})) \\\\\n&c_{\\text{Cpt, Cpt}}[x_{\\text{Cpt}}, y_{\\text{Cpt}}] = \\text{movex}(\\text{change}(\\text{CptOrigin}, \\text{color}(x_{\\text{Cpt}})), x(x_{\\text{Cpt}})), y(x_{\\text{Cpt}}))\n\\end{align*}\n\\]\n\n**Definition 4.2.** Let $\\langle \\Sigma, E \\rangle$ be an equational specification and let $C = \\{c_{S,T}\\}$ be a pre-coercion system.\n\n(i) Then $C$ is a coercion system for $\\langle \\Sigma, E \\rangle$ if, for every $n \\in \\mathbb{N}$, every $g \\in \\text{Op}_{n}$ with admissible type $T_{1}, \\ldots, T_{n} \\rightarrow T$, and for all $(S_{1}, \\ldots, S_{n}) \\leq (T_{1}, \\ldots, T_{n})$,\n\n\\[\n\\begin{align*}\n&\\text{(coer-fbeh)} \\quad E \\vdash_{\\text{beh}} \\forall H(g(c_{S_{1}, T_{1}}[y_{1}], \\ldots, c_{S_{n}, T_{n}}[y_{n}]) = c_{S, T}[g(y_{1}, \\ldots, y_{n})]), \\\\\n&\\text{where } S = \\text{ResType}(g, S_{1}, \\ldots, S_{n}) \\text{ and } H = \\langle y_{1}, S_{1}, \\ldots, y_{n}, S_{n} \\rangle.\n\\end{align*}\n\\]\n\n(ii) We say that $\\langle \\Sigma, E, C \\rangle$ is an equational specification with coercions if $\\langle \\Sigma, E \\rangle$ is an equational specification and $C$ is a coercion system for $\\langle \\Sigma, E \\rangle$. \\[\\square\\]\n\n**Example 4.3.** We show that the pre-coercion system of Example 4.1, $C_{pt}$, is not a coercion system for $(\\Sigma_{pt}, E_{pt})$, and thus $(\\Sigma_{pt}, E_{pt}, C_{pt})$ is not an equational specification with coercions. For this purpose we show that one of the coercion equations, viz., the following $(cp, Cpt, i; \\text{int})$-equation, fails to be a formal behavioral equivalence over $E_{pt}$:\n\n\\[\n\\text{movex}(\\text{Cpt}, Cpt, cp, i) = c_{\\text{pt, Cpt}}[\\text{movex}(cp, i)]\n\\]\n\nIn view of Def 3.6 it suffices to show that the following equation\n\n\\[\n\\text{fails-in-pt} \\quad \\text{color}(\\text{movex}(\\text{Cpt}, Cpt, cp, i)) = \\text{color}(c_{\\text{Cpt, Cpt}}[\\text{movex}(cp, i)])\n\\]\n\nfails to be a nominal equational consequence of $E_{pt}$, and for this purpose we show that the $(\\Sigma_{pt}, E_{pt})$-equation (fails-in-pt) is invalid in the model $PT$ of $E_{pt}$. To see this consider the $(cp, Cpt, i; \\text{int})$-environment $\\langle 3, 4, 5, 6 \\rangle$; in this environment we can calculate as follows for the left-hand side of equation (fails-in-pt). It is convenient to present the calculation in the style of Dijkstra and Gries.\n\n\\[\n\\begin{align*}\n\\text{color}(\\text{movex}(\\text{Cpt, Cpt, cp}, i))^{PT} &\\equiv \\langle \\text{by definition of the coercions} \\rangle \\\\\n&\\text{color}(\\text{movex}(\\text{movey}(\\text{change}(\\text{CptOrigin}, \\text{color}(\\text{cp})), \\text{color}(\\text{cp})), \\text{color}(\\text{cp})))^{PT} \\\\\n\\end{align*}\n\\]\n\n\\[\n\\begin{align*}\n&\\equiv \\langle \\text{by definition of evaluation} \\rangle \\\\\n&\\text{color}^{PT}(\\text{movex}^{PT}(\\text{movey}^{PT}(\\text{movex}^{PT}(\\text{change}^{PT}(\\text{CptOrigin}^{PT}, \\text{color}^{PT}(\\langle 3, 4, 5 \\rangle)), \\\\\n\\text{x}^{PT}(\\langle 3, 4, 5 \\rangle)), y^{PT}(\\langle 3, 4, 5 \\rangle)))^{PT} \\\\\n\\end{align*}\n\\]\n\n\\[\n\\begin{align*}\n&\\equiv \\langle \\text{by definition of color, x, and y in } PT \\rangle \\\\\n&\\text{color}^{PT}(\\text{movex}^{PT}(\\text{movey}^{PT}(\\text{movex}^{PT}(\\text{change}^{PT}(\\text{CptOrigin}^{PT}, 3, 4), 6))) \\\\\n\\end{align*}\n\\]\n\n\\[\n\\begin{align*}\n&\\equiv \\langle \\text{by definition of CptOrigin and change in } PT \\rangle \\\\\n&\\text{color}^{PT}(\\text{movex}^{PT}(\\text{movex}^{PT}(\\langle 0, 0, 5 \\rangle), 3, 4), 6)) \\\\\n\\end{align*}\n\\]\n\n\\[\n\\begin{align*}\n&\\equiv \\langle \\text{by definition of movex in } PT \\rangle \\\\\n&\\text{color}^{PT}(\\text{movex}^{PT}(\\langle 3, 0, 0 \\rangle, 4), 6)) \\\\\n\\end{align*}\n\\]\n\n\\[\n\\begin{align*}\n&\\equiv \\langle \\text{by definition of movex in } PT \\rangle \\\\\n&\\text{color}^{PT}(\\text{movex}^{PT}(\\langle 3, 4, 0 \\rangle, 6))\n\\end{align*}\n\\]\n= ⟨by definition of \\( \\text{movex} \\) in \\( PT \\)⟩\n\\( \\text{color}^{PT}(9, 4, 3) \\)\n\n= ⟨by definition of \\( \\text{color} \\) in \\( PT \\)⟩\n3\n\nHowever, the result obtained above is different than that for the right-hand side of equation (fails-in-pt) in the same environment, as the following calculation shows.\n\\( \\text{color}(c_{\\text{Cpt:CPt}}[\\text{movex}(cp, i)])^{PT}([3, 4, 5, 6]) \\)\n\n= ⟨by definition of \\( c_{\\text{Cpt:CPt}}[x_{\\text{CPt:CPt}}] \\)⟩\n\\( \\text{color}(\\text{movex}(\\text{movex}(\\text{CptOrigin})(\\text{color}(\\text{movex}(cp, i))), \\text{x}(\\text{movex}(cp, i))), \\text{y}(\\text{movex}(cp, i)))^{PT}([3, 4, 5, 6]) \\)\n\n= ⟨by definition of \\( \\text{evaluation} \\)⟩\n\\( \\text{color}^{PT}(\\text{movex}^{PT}(\\text{movex}^{PT}(\\text{CptOrigin}^{PT}, \\text{color}^{PT}(\\text{movex}^{PT}([3, 4, 5, 6])), \\text{x}^{PT}(\\text{movex}^{PT}([3, 4, 5, 6])), \\text{y}^{PT}(\\text{movex}^{PT}([3, 4, 5, 6]))) \\)\n\n= ⟨by definition of \\( \\text{movex} \\) in \\( PT \\)⟩\n\\( \\text{color}^{PT}(\\text{movex}^{PT}(\\text{movex}^{PT}(\\text{CptOrigin}^{PT}, \\text{color}^{PT}([9, 4, 3])), \\text{x}^{PT}([9, 4, 3]), \\text{y}^{PT}([9, 4, 3])) \\)\n\n= ⟨by definition of \\( \\text{color}, \\text{x}, \\) and \\( \\text{y} \\) in \\( PT \\)⟩\n\\( \\text{color}^{PT}(\\text{movex}^{PT}(\\text{movex}^{PT}(\\text{CptOrigin}^{PT}, [3, 9, 4])) \\)\n\n= ⟨by definition of \\( \\text{CptOrigin} \\) and \\( \\text{change}_c \\) in \\( PT \\)⟩\n\\( \\text{color}^{PT}(\\text{movex}^{PT}([0, 3, 9, 4])) \\)\n\n= ⟨by definition of \\( \\text{movex} \\) in \\( PT \\)⟩\n\\( \\text{color}^{PT}(\\text{movex}^{PT}([9, 0, 0, 4])) \\)\n\n= ⟨by definition of \\( \\text{movex} \\) in \\( PT \\)⟩\n\\( \\text{color}^{PT}([9, 4, 0]) \\)\n\n= ⟨by definition of \\( \\text{color} \\) in \\( PT \\)⟩\n0 □\n\n**Example 4.4.** On the other hand, the pre-coercion system of Example 4.1, \\( C_{\\text{pt}} \\), is a coercion system for \\( (\\Sigma_{\\text{pt}}, E_{\\text{cpt}}) \\), and hence \\( (\\Sigma_{\\text{pt}}, E_{\\text{cpt}}, C_{\\text{pt}}) \\) is an equational specification with coercions. Because the coercion \\( c_{\\text{int, int}}[x_{\\text{int}}] \\) is lexically equal to \\( x_{\\text{int}} \\), all the equations of the form \\( (\\text{coer-fbeh}) \\) that involve only visible operations are lexical identities. Thus it suffices to consider only operations in the signature that have admissible types that take arguments of the non-visible types \\( \\text{Pt} \\) and \\( \\text{Cpt} \\) and to show that the associated equations \\( (\\text{coer-fbeh}) \\) are formal behavioral equivalences over \\( E_{\\text{cpt}} \\). Thus, in view of Cor. 3.11 it suffices to show that each equation in Figure 7 is a nominal equational consequence of \\( E_{\\text{cpt}} \\) with the three formal behavioral equivalences of Example 3.9 adjoined.\n\nThe first six formal behavioral equivalences in Figure 7, for the operations \\( x \\) and \\( y \\), all have similar proofs. The following proof for the second of these is representative.\nfor all \\( p : \\text{Pt}, p_1 : \\text{Pt}, p_2 : \\text{Pt}, cp : \\text{Cpt}, cp_1 : \\text{Cpt}, cp_2 : \\text{Cpt}, \\) and \\( i : \\text{int} :\\)\n\n\\[\n\\begin{align*}\n\\text{x}(c_{\\text{Cpt, Pt}}[p]) &= c_{\\text{int, int}}[x(p)] \\\\\n\\text{x}(c_{\\text{Cpt, Cpt}}[cp]) &= c_{\\text{int, int}}[x(cp)] \\\\\n\\text{y}(c_{\\text{Cpt, Pt}}[p]) &= c_{\\text{int, int}}[y(p)] \\\\\n\\text{y}(c_{\\text{Cpt, Cpt}}[cp]) &= c_{\\text{int, int}}[y(cp)] \\\\\n\\text{movex}(c_{\\text{Cpt, Pt}}[p], c_{\\text{int, int}}[i]) &= c_{\\text{Cpt,Pt}}[\\text{movex}(p, i)] \\\\\n\\text{movex}(c_{\\text{Cpt, Cpt}}[cp], c_{\\text{int, int}}[i]) &= c_{\\text{Cpt, Pt}}[\\text{movex}(cp, i)] \\\\\n\\text{movex}(c_{\\text{Cpt, Cpt}}[cp], c_{\\text{int, int}}[i]) &= c_{\\text{Cpt, Cpt}}[\\text{movex}(cp, i)] \\\\\n\\text{movex}(c_{\\text{Cpt, Pt}}[p], c_{\\text{int, int}}[i]) &= c_{\\text{Cpt, Pt}}[\\text{movex}(p, i)] \\\\\n\\text{movex}(c_{\\text{Cpt, Cpt}}[cp], c_{\\text{int, int}}[i]) &= c_{\\text{Cpt, Pt}}[\\text{movex}(cp, i)] \\\\\n\\text{movex}(c_{\\text{Cpt, Cpt}}[cp], c_{\\text{int, int}}[i]) &= c_{\\text{Cpt, Cpt}}[\\text{movex}(cp, i)] \\\\\n\\text{xdiff}(c_{\\text{Cpt, Pt}}[p_1], c_{\\text{Cpt, Pt}}[p_2]) &= c_{\\text{int, int}}[\\text{xdiff}(p_1, p_2)] \\\\\n\\text{xdiff}(c_{\\text{Cpt, Cpt}}[cp], c_{\\text{Cpt, Pt}}[p]) &= c_{\\text{int, int}}[\\text{xdiff}(cp, p)] \\\\\n\\text{xdiff}(c_{\\text{Cpt, Pt}}[p], c_{\\text{Cpt, Cpt}}[cp]) &= c_{\\text{int, int}}[\\text{xdiff}(p, cp)] \\\\\n\\text{xdiff}(c_{\\text{Cpt, Cpt}}[cp_1], c_{\\text{Cpt, Cpt}}[cp_2]) &= c_{\\text{int, int}}[\\text{xdiff}(cp_1, cp_2)]\n\\end{align*}\n\\]\n\n**Figure 7.** Equations to be proved formal behavioral equivalences over \\( E_{\\text{cpt}} \\)\nto show that the pre-coercion system of Exam. 4.1, \\( C_{\\text{pt}} \\), is a coercion system for \\( \\langle \\Sigma_{\\text{pt}}, E_{\\text{cpt}} \\rangle \\).\n\n\\[\n\\begin{align*}\nx(c_{\\text{Cpt, Pt}}[cp]) &= x(\\text{movex}(\\text{movex}(\\text{PtOrigin}, x(cp)), y(cp))), & \\text{by def. of } c_{\\text{Cpt, Pt}}[x_{\\text{Cpt}} : \\text{Cpt}] \\\\\n&= x(\\text{movex}(\\text{PtOrigin}, x(cp))), & \\text{by axiom (x-movex) of } E_{\\text{cpt}} \\\\\n&= \\text{add}(x(\\text{PtOrigin}), x(cp)), & \\text{by axiom (x-movex) of } E_{\\text{cpt}} \\\\\n&= \\text{add}(0, x(cp)), & \\text{by axiom in (x-PtOrigin) of } E_{\\text{cpt}} \\\\\n&= x(cp), & \\text{by axioms for the integers} \\\\\n&= c_{\\text{int, int}}[x(cp)], & \\text{by def. of } c_{\\text{int, int}}[x_{\\text{int}} : \\text{int}].\n\\end{align*}\n\\]\n\nThe second set of six formal behavioral equivalences in Figure 7, for the operations \\text{movex} and \\text{movex}, all have similar proofs. The following proof for the third of these (which is equation (fails-in-pt)) is representative. Note the crucial use of the equations from Example 3.9.\n\n\\[\n\\begin{align*}\n\\text{movex}(c_{\\text{Cpt, Cpt}}[cp], c_{\\text{int, int}}[i]) &= \\langle \\text{by definition of the coercions} \\rangle \\\\\n\\text{movex}(&\\text{movex}(\\text{movex}(\\text{changec}(\\text{PtOrigin, color}(cp)), x(cp)), y(cp)), i) \\\\\n&= \\langle \\text{by the third formal behavioral equivalence in Example 3.9} \\rangle \\\\\n\\text{movex}(\\text{movex}(&\\text{movex}(\\text{changec}(\\text{PtOrigin, color}(cp)), x(cp)), i), y(cp)) \\\\\n&= \\langle \\text{by the first formal behavioral equivalence in Example 3.9} \\rangle \\\\\n\\text{movex}(\\text{movex}(\\text{changec}(\\text{PtOrigin, color}(cp)), \\text{add}(x(cp), i)), y(cp)) \\\\\n&= \\langle \\text{by axiom (x-movex) of } E_{\\text{cpt}} \\rangle\n\\end{align*}\n\\]\nmovey(movey(changev(CPtOrigin.color(cp)), x(movev(cp, i))), y(cp))\n= (by axiom (color-movev) of $E_{cpt}$)\nmovey(movev(changev(CPtOrigin.color(movev(cp, i))), x(movev(cp, i))), y(cp))\n= (by axiom (color-movev) of $E_{cpt}$)\nmovev(movev(changev(CPtOrigin.color(movev(cp, i))), x(movev(cp, i))), y(movev(cp, i)))\n= (by definition of $c_{Cpt,Cpt}[x_{Cpt}:Cpt]$)\n$c_{Cpt,Cpt}[movev(cp, i)]$\n\nThe last four formal behavioral equivalences in Figure 7 have straight-forward proofs. □\n\n5. Correct Behavioral Subtyping\n\nWe show in this section that every specification with coercions is sound in the sense that it implies correct behavioral subtyping. This requires a few preliminaries.\n\nRecall that we defined an algebra to be a model of an equational specification $⟨Σ, E⟩$, (i.e., a member of $Mod(E)$), if the equations of $E$ are satisfied in every dynamic environment; an alternative, narrower notion of model requires that the equations of $E$ be satisfied by every virtual environment. As noted earlier a $Σ$-algebra is a model in this sense if and only if its order-sorted transform is model (in the wider sense); so restricting ourselves to this narrower notion of model is tantamount to considering only order-sorted models. But order-sorted models are not a suitable framework for developing a useful theory of correct behavioral subtyping because every class of order-sorted algebras, which meets the criteria of a specification given in [23], is automatically correctly behaviorally subtyped; this idea is made precise in Section 7. Therefore, to avoid begging the question of what correct behavioral subtyping means, we restrict our attention to models of $⟨Σ, E⟩$ in the wider sense. Moreover, we consider only nominal models.\n\nDefinition 5.1. Let $⟨Σ, E⟩$ be an equational specification, Then $⟨Σ, E⟩$ is correctly behaviorally subtyped if $Mod_{nom}(E)$ is correctly behaviorally subtyped. □\n\nSee Appendix A (and our earlier work [23]) for the model-theoretic definition of correct behavioral subtyping. Instead of using the model-theoretic definition directly, we use a result from our earlier work that nominal standard simulations are sound for correct behavioral subtyping [21, 23]. The reason for doing this is that standard simulations correspond directly to coercion systems. We now define the notions of homomorphic standard relation and nominal standard simulation between algebras.\n\nDefinition 5.2 (Standard Homomorphic Relation, VIS-Identical, Nominal [22, 23]). Let $A$ and $B$ be $Σ$-algebras. A homomorphic standard relation between $A$ and $B$ is a sorted binary relation $R = ⟨R_T : T ∈ TYPE, R_T ⊆ A_1^T × B_1^T⟩$ such that the following homomorphism condition holds: for all types $T$ and $(S_1, . . . , S_n) ≤ (T_1, . . . , T_n)$, for every operation $g ∈ Op_n$ such that $T = ResType(g, T_1, . . . , T_n)$, and for all $(a_1, . . . , a_n) ∈ A_{S_1} × · · · × A_{S_n}$ and $(b_1, . . . , b_n) ∈ B_{T_1} × · · · × B_{T_n}$,\n\n$$(a_1, . . . , a_n) R_{T_1} × · · · × R_{T_n} (b_1, . . . , b_n) \\text{ implies } g^A(a_1, . . . , a_n) R_T g^B(b_1, . . . , b_n).$$\n\nA homomorphic standard relation $R$ is VIS-identical if the visible reducts of $A$ and $B$ are identical and $R_V$ is included in the identity relation on $A_V (= B_V)$ for every visible type $V$, i.e., the only visible element that a given visible element can simulate is itself.\n\nA homomorphic standard relation $R$ is nominal if $R_T ⊆ A_T × B_T$ for every type $T$. □\nLemma 5.3. Let \\( \\langle \\Sigma, E \\rangle \\) be an equational specification and let \\( A \\) be a nominal \\( \\Sigma \\)-algebra. \\( FB(E, A) \\) is a nominal homomorphic standard relation on \\( A \\) and itself. Moreover, if \\( A \\) is a model of \\( E \\), then \\( FB(E, A) \\) is VIS-identical.\n\nProof. We observe first of all that \\( FB(E, A) \\) is nominal because \\( A \\) is nominal, so Def. 3.14 gives a nominal relation. Let \\( g \\in Op_n \\), and let \\( T_1, \\ldots, T_n \\rightarrow T \\) be an admissible type of \\( g \\). Let \\( (a_1, \\ldots, a_n) \\) and \\( (b_1, \\ldots, b_n) \\) be sequences in \\( A_{T_1} \\times \\cdots \\times A_{T_n} \\) such that \\( a_i FB(E)T_i b_i \\) for each \\( i \\leq n \\). For each \\( i \\leq n \\) choose a type context \\( H_i \\), an \\( H_i \\)-environment \\( \\bar{c}_i \\) in \\( A \\), and an \\( H_i \\)-equation \\( \\forall H_i(t_i = t'_i) \\) such that \\( E \\vdash_{beh} \\forall H_i(t_i = t'_i) \\) and \\( \\langle a_i, b_i \\rangle = \\langle t_i^A[\\bar{c}_i], t'_i^A[\\bar{c}_i] \\rangle \\) for every \\( i \\leq n \\). Clearly these choices can be made so that the \\( \\text{Var}(H_i) \\) are pairwise disjoint. Let \\( H = H_1 \\cup \\cdots \\cup H_n \\) and \\( \\bar{c} = \\bar{c}_1 \\cup \\cdots \\cup \\bar{c}_n \\). Then by the fact that behavioral consequence is closed under equational consequence (Cor. 3.11) we have \\( E \\vdash_{beh} \\forall H(g(t_1, \\ldots, t_n) = g(t'_1, \\ldots, t'_n)) \\).\n\nThus \\( \\langle g^A(a_1, \\ldots, a_n), g^A(b_1, \\ldots, b_n) \\rangle = \\langle g(t_1, \\ldots, t_n)^A[\\bar{c}], g(t'_1, \\ldots, t'_n)^A[\\bar{c}] \\rangle \\in FB(E)T \\). And so \\( FB(E) \\) is a homomorphic standard relation on \\( A \\).\n\nNow assume \\( A \\) is a model of \\( E \\). Suppose \\( V \\in \\text{VIS} \\) and \\( a FB(E)T b \\). Choose an type context \\( H \\), an \\( H \\)-environment \\( \\bar{c} \\), and an \\( H \\)-equation \\( \\forall H(t = t') \\) of type \\( V \\) such that \\( E \\vdash_{beh} \\forall H(t = t') \\) and \\( \\langle a, b \\rangle = \\langle t^A[\\bar{c}], t'^A[\\bar{c}] \\rangle \\). Trivially, \\( E \\cup \\{ \\forall H(t = t') \\} \\vdash_{\\text{Nom}} \\forall H(t = t') \\), and hence, since \\( \\forall H(t = t') \\) is of visible type, \\( E \\vdash_{\\text{Nom}} \\forall H(t = t') \\) by Thm. 3.10. Thus \\( t^A[\\bar{c}] = t'^A[\\bar{c}] \\), since \\( A \\) is a model of \\( E \\), i.e., \\( a = b \\). Thus \\( FB(E) \\) is VIS-identical. □\n\nIt is clear from its definition that \\( FB(E) \\) is sorted equivalence relation on \\( A \\), it particular it is transitive.\n\nDefinition 5.4 (Nominal Standard Simulation [23]). A standard relation, \\( R \\), between \\( A \\) and \\( B \\) is a nominal standard simulation of \\( B \\) by \\( A \\) if \\( R \\) is homomorphic, VIS-identical, and if for every type \\( T \\), and for every element \\( a \\) of \\( A \\) of virtual type \\( T \\) (i.e., for every element \\( a \\in A_T^v \\)), there is an element \\( b \\) of \\( B \\) of dynamic type \\( T \\) (i.e., \\( b \\in B_T \\)), such that \\( a R_T b \\). □\n\nThe meaning of “nominal” for a standard simulation is different from that of a homomorphic standard relation. For nominal standard simulations, for every element of \\( A \\) and each of its virtual types, there is an element of \\( B \\) of corresponding dynamic type to which it is related; however, it may also be related to elements of \\( B \\) that are not of corresponding dynamic type. On the other hand, there may be elements of \\( A \\) that a homomorphic standard relation relates to no element of \\( B \\), but each element to which it is related must be of the same dynamic type. So a nominal standard simulation need not be nominal as a homomorphic relation and vice-versa.\n\nThe statement of the algebraic soundness theorem below uses as a hypothesis the fixed data assumption that was introduced in Section 2.4 but not actually used up to this point. This is the assumption that the class of restricted models of a specification is VIS-categorical, i.e., that their visible reducts are the same.\n\nTheorem 5.5 (Algebraic Soundness Theorem [23]). Let \\( \\langle \\Sigma, E \\rangle \\) be an equational specification and let \\( \\text{Mod}_{\\text{Nom}}(E) \\) be VIS-categorical. If for every \\( A \\in \\text{Mod}_{\\text{Nom}}(E) \\) there exists a \\( B \\in \\text{Mod}_{\\text{Nom}}(E) \\) and a nominal standard simulation of \\( B \\) by \\( A \\), then \\( \\langle \\Sigma, E \\rangle \\) is correctly behaviorally subtyped.\nThe proof of this theorem is given in Section A.1.\n\n**Theorem 5.6 (Proof-Theoretic Soundness Theorem).** Let \\((\\Sigma, E, C)\\) be an equational specification with coercions. Then \\((\\Sigma, E)\\) is correctly behaviorally subtyped.\n\n**Proof.** Let \\(C = \\{c_{S,T}\\}\\) be the coercion system. Let \\(A \\in \\text{Mod}_{\\text{Nom}}(E)\\). Let \\(C^A = \\langle C^A_T : T \\in \\text{TYPE} \\rangle\\) be the sorted binary relation such that for each type \\(T\\), \\(C^A_T\\) is defined as follows:\n\n\\[\nC^A_T := \\{ (a, c_{S,T}[x_S : S]^A[a]) : S \\leq T, a \\in A_S \\}.\n\\]\n\nNote that \\(C^A\\) is a sorted function, i.e., \\(C^A_T\\) is a function from \\(A_S\\) to \\(A_T\\) for all \\(S, T \\in \\text{TYPE}\\) such that \\(S \\leq T\\); that is, \\(C^A_T\\) is a function from \\(A^n_S\\) to \\(A^n_T\\).\n\nLet \\(C^A, FB(E, A) = \\langle C^A_T, FB(E, A)_T : T \\in \\text{TYPE} \\rangle\\) be the composition of the two relations; that is, \\(a C^A_T b\\) if there exists a \\(d\\) such that \\(a C^A_d d FB(E, A)_T b\\).\n\nWe will show that \\(C^A, FB(E, A)\\) is a nominal standard simulation of \\(A\\) by itself.\n\nWe note first of all that \\(C^A, FB(E, A)\\) is nominal (as a simulation) since \\(A\\) is nominal and \\(FB(E, A)\\) is nominal (as a homomorphic relation). For each visible type \\(V \\in \\text{VIS}\\), \\(C^A_V\\) is the identity function, because \\(c_{V,V} : x_V : V\\) is lexically equal to \\(x_V\\), and \\(FB(E, A)_V\\) is also the identity relation, by Lem. 5.3. Thus \\(C^A, FB(E, A)\\) is VIS-identical. We now verify the homomorphism condition.\n\nLet \\(g \\in \\text{Op}_n\\) with admissible types \\(T_1, \\ldots, T_n \\rightarrow T\\) and \\(S_1, \\ldots, S_n \\rightarrow S\\) with \\((S_1, \\ldots, S_n) \\leq (T_1, \\ldots, T_n)\\), and hence necessarily also \\(S \\leq T\\). Let \\((a_1, \\ldots, a_n) \\in A_{S_1} \\times \\cdots \\times A_{S_n}\\) and \\((b_1, \\ldots, b_n) \\in A_{T_1} \\times \\cdots \\times A_{T_n}\\) such that\n\n\\[\na_i C^A_{T_i} b_i \\text{ for each } i \\leq n.\n\\]\n\nThen by definition of the composition of relations, there are \\((d_1, \\ldots, d_n) \\in A_{T_1} \\times \\cdots \\times A_{T_n}\\) such that\n\n\\[\na_i C^A_{T_i} d_i FB(E, A)_{T_i} b_i \\text{ for each } i \\leq n.\n\\]\n\nSo by definition of \\(C^A\\), for each \\(i \\leq n\\), \\(d_i = c_{S_i,T_i}^A[a_i]\\). We calculate as follows.\n\n\\[\ng^A(a_1, \\ldots, a_n) C^A_{T_1} c_{S_1,T_1}[x_{S_1} : S]^A[a_1, \\ldots, a_n] = c_{S_1,T_1}[g(c_{S_1,T_1}[x_{S_1}], \\ldots, c_{S_n,T_n}[x_{S_n}])]^A[a_1, \\ldots, a_n]\n\\]\n\nby definition of evaluation\n\n\\[\nFB(E, A)_T g(c_{S_1,T_1}[x_{S_1}], \\ldots, c_{S_n,T_n}[x_{S_n}])^A[a_1, \\ldots, a_n]\n\\]\n\nby definition of coercion system\n\n\\[\ng^A(c_{S_1,T_1}^A[a_1], \\ldots, c_{S_n,T_n}^A[a_n])\n\\]\n\nby definition of evaluation\n\n\\[\ng^A(d_1, \\ldots, d_n).\n\\]\n\nThus \\(g^A(a_1, \\ldots, a_n) C^A_{T_1} FB(E, A)_T g^A(d_1, \\ldots, d_n)\\). Now from assumption (10) and from the fact that \\(FB(E, A)\\) is a standard homomorphic relation, we obtain\n\n\\[\ng^A(d_1, \\ldots, d_n) FB(E, A)_T g^A(b_1, \\ldots, b_n).\n\\]\nPutting this together with the above calculation we obtain that\n\\[ g^A(a_1, \\ldots, a_n); \\text{FB}(E, A)_T; \\text{FB}(E, A)_T g^A(b_1, \\ldots, b_n), \\]\nand hence \\( g^A(a_1, \\ldots, a_n) \\preceq^T \\text{FB}(E, A)_T g^A(b_1, \\ldots, b_n) \\) since \\( \\text{FB}(E, A) \\) is transitive.\n\nSo \\( \\text{CA}_T; \\text{FB}(E, A)_T \\) is a nominal simulation of \\( A \\) by itself. Thus \\( \\langle \\Sigma, E \\rangle \\) is correctly behaviorally subtyped by the algebraic soundness theorem, Thm. 5.5.\n\n\\[ \\square \\]\n\n6. Coercion Systems are not Complete\n\nIn this section we give an counterexample to the converse of Theorem 5.6. That is, this example shows that a coercion system does not always exist for an equational specification that is correctly behaviorally subtyped.\n\n**Example 6.1.** Let \\( \\Sigma_3 \\) be a signature with the three types: \\text{bool}, \\text{sort}, and \\text{subsort}. The only visible type is \\text{bool}, and the subtype relation is such that \\( T \\leq T \\), for each type \\( T \\), and also \\text{subsort} \\subseteq \\text{sort}. There are four constants: \\text{s0} and \\text{s1} of type \\text{sort}, and \\text{ss0} and \\text{ss1} of type \\text{subsort}. The only operation, apart from the standard booleans, is the unary operation \\text{test} with \\text{ResType(test.sort)} = \\text{ResType(test.subsort)} = \\text{bool}. The set of equations, \\( E_3 \\), contains only the boolean axioms and the equations shown in Figure 8. (The constants \\text{ss0} and \\text{ss1} are not involved in these equations; they are introduced here for use in the following example.) The class of models, \\( \\text{Mod}_{\\text{nom}}(E_3) \\), consists of all models \\( A \\) of \\( E_3 \\) such that \\( A_{\\text{bool}} \\) is the two-element boolean algebra \\{tt, ff\\}, where \\text{true}^A = tt and \\text{false}^A = ff.\n\n\\[\n\\begin{align*}\n\\text{(test-s0)} & \\quad \\text{test(s0)} = \\text{false} \\\\\n\\text{(test-s1)} & \\quad \\text{test(s1)} = \\text{true}\n\\end{align*}\n\\]\n\n**Figure 8.** Equations in \\( E_3 \\); to save space, the standard equations for the booleans are not shown.\n\nTo show that \\( \\langle \\Sigma_3, E_3 \\rangle \\) is correctly behaviorally subtyped, by Theorem 5.5 it suffices to show that for all restricted models, \\( A \\) in \\( \\text{Mod}_{\\text{nom}}(E_3) \\), there is an \\( B \\) in \\( \\text{Mod}_{\\text{nom}}(E_3) \\) such that there is a nominal standard simulation \\( \\mathcal{R} \\) of \\( B \\) by \\( A \\). So let \\( A \\) be a restricted model in \\( \\text{Mod}_{\\text{nom}}(E_3) \\). Our choice for \\( B \\) is the algebra \\( A \\) itself. To define the required simulation, it is helpful to define two data elements \\( b_t, b_f \\in A_{\\text{sort}} \\) such that \\( b_t = \\text{so}^A \\) and \\( b_f = \\text{si}^A \\).\n\nNote that by the equations in \\( E_3 \\), \\text{test}^A(b_t) = \\text{ff} and \\text{test}^A(b_f) = \\text{tt}.\n\nNow define \\( \\mathcal{R} \\) such that \\( \\mathcal{R}_{\\text{bool}} \\) and \\( \\mathcal{R}_{\\text{subsort}} \\) are the identity relations on the two-element boolean algebra and \\( A_{\\text{subsort}} \\), respectively. \\( \\mathcal{R}_{\\text{sort}} \\cap (A_{\\text{sort}} \\times B_{\\text{sort}}) \\) is the identity relation, and \\( \\mathcal{R}_{\\text{sort}} \\cap (A_{\\text{subsort}} \\times B_{\\text{subsort}}) \\) is\n\n\\[\n\\{ a \\in A_{\\text{subsort}} : \\text{test}^A(a) = \\text{tt} \\} \\times \\{ b_t \\} \\cup \\{ a \\in A_{\\text{subsort}} : \\text{test}^A(a) = \\text{ff} \\} \\times \\{ b_f \\}.\n\\]\n\nIt is easy to see \\( \\mathcal{R} \\) is a homomorphic. For example, suppose \\( a \\mathcal{R}_{\\text{sort}} b \\), with \\( a \\in A_{\\text{subsort}} \\) and \\( b \\in A_{\\text{sort}} \\). If \\( \\text{test}^A(a) = \\text{tt} \\), then \\( b = b_t \\), and if \\( \\text{test}^A(a) = \\text{ff} \\), then \\( b = b_f \\); in both case we have \\( \\text{test}^A(a) = \\text{test}^A(b) \\). \\( \\mathcal{R} \\) is obviously nominal and VIS-identical. So it is a nominal, standard simulation.\n\nThere is however no coercion system for \\( \\langle \\Sigma_3, E_3 \\rangle \\). We show this by contradiction. Suppose that there were a coercion system \\( \\{ c_{\\Sigma, T} \\} \\). The only \\( \\Sigma_3 \\)-terms of nominal type \\text{sort}\nare variables and the two constants $s_0$ and $s_1$. So there are only three possibilities for coercions from $\\text{subsort}$ to $\\text{sort}$.\n\nThe first possibility for this coercion is that the coercion defined using a variable of type $\\text{sort}$, such as:\n\n$$c_{\\text{subsort}, \\text{sort}}[x_{\\text{subsort}}: \\text{subsort}] = x_{\\text{sort}}.$$ \n\nIn this case, it follows that\n\n$$\\text{test}(c_{\\text{subsort}, \\text{sort}}[x_{\\text{subsort}}: \\text{subsort}])$$\n\nis the term $\\text{test}(x_{\\text{sort}})$ and because $\\text{bool}$ is a visible type, $c_{\\text{bool}, \\text{bool}}$ is the identity, and thus\n\n$$c_{\\text{bool}, \\text{bool}}[\\text{test}(x_{\\text{subsort}})]$$\n\nis the term $\\text{test}(x_{\\text{subsort}})$.\n\nTaking the operation $g$ to be $\\text{test}$, $S$ to be $\\text{subsort}$ and $T$ to be $\\text{sort}$ in the defining condition (coer-ident) for a coercion system, we get\n\n$$E_3 \\vdash \\text{test}(x_{\\text{sort}}) = \\text{test}(x_{\\text{subsort}}).$$\n\nBut this is invalid. To see this, let $D \\in \\text{Mod}_{\\text{nom}}(E_3)$, and let $d \\in D_{\\text{subsort}}$ be given. Then a counter-example to the validity of this equation is provided by the nominal environment that maps $x_{\\text{subsort}}$ to $d$ and $x_{\\text{sort}}$ to $s_1^D$ if $\\text{test}^D(d) = \\text{ff}$, and $s_0^D$ otherwise. For example, if $\\text{test}^D(d) = \\text{ff}$, then the right hand side of this equation is $\\text{ff}$, while the left hand side is $\\text{test}(s_1)^D = \\text{tt}$.\n\nThe second possibility for this coercion is that the coercion defined using the constant $s_0$ of type $\\text{sort}$, such as:\n\n$$c_{\\text{subsort}, \\text{sort}}[x_{\\text{subsort}}: \\text{subsort}] = s_0.$$ \n\nAs above, it follows that $\\text{test}(c_{\\text{subsort}, \\text{sort}}[x_{\\text{subsort}}: \\text{subsort}])$ is the term $\\text{test}(s_0)$ and thus that\n\n$$E_3 \\vdash \\text{test}(s_0) = \\text{test}(x_{\\text{subsort}}).$$\n\nBut this is also invalid, because there are models of $E_3$ in which $\\text{test}$ returns $\\text{tt}$ for elements of the subsort.\n\nSimilarly the third possibility for this coercion, that it is defined using the constant $s_1$ of type $\\text{sort}$ also leads to an invalid equation. Hence there is no coercion system for this example.\n\nNote that $\\langle \\Sigma_3, E_3 \\rangle$ in the above example has only unary methods (see Thm. A.3 below), so the algebraic completeness theorem for specifications with only unary methods does not lead to a corresponding completeness result for coercion.\n\n**Example 6.2.** Coercions are also not complete for term-generated specifications. To see this, restrict the set of models in the previous example to be term-generated. This does not change the example’s character or its conclusions.\n\nThe above examples are quite underspecified; even though they have constructors for objects of type $\\text{sort}$ and $\\text{subsort}$, the constructors of type $\\text{subsort}$ are unconstrained by the equations in $E_3$. A similar result can be shown if there were no constructors at all. This is often the case in object-oriented programming; for example, interfaces in Java have no operations that correspond to constructors. Hence the technique of using coercion functions seems to be fundamentally incomplete for proving behavioral subtyping.\nTheorem 7.1. An equational specification\n\nAssume\n\nProof.\n\nequations, \\( E \\) begs the question whether an equational specification is correctly behaviorally subtyped. The assertion, made at the beginning of Section 5, that the restriction to order-sorted models of coercion relation that reflects at the formal level the nominal standard simulations of the algebraic completeness theorem, which are not in general functional. We leave this as future work.\n\n7. Discussion\n\nIn this section we discuss some further aspects of our work.\n\n7.1. Order-sorted algebras and correct behavioral subtyping. We make precise the assertion, made at the beginning of Section 5, that the restriction to order-sorted models begs the question whether an equational specification is correctly behaviorally subtyped.\n\nDefine the class \\( \\text{Mod}_{\\text{nom}}^\\circ(E) \\) of order-sorted transforms of nominal models of a set of equations, \\( E \\), to be \\( \\{ A^\\circ : A \\in \\text{Mod}_{\\text{nom}}(E) \\} \\).\n\n**Theorem 7.1.** An equational specification \\( \\langle \\Sigma, E \\rangle \\) is correctly behaviorally subtyped iff\n\n\\[ \\text{Mod}_{\\text{nom}}^\\circ(E) = \\text{Mod}_{\\text{ord}}(E). \\]\n\n**Proof.** Assume \\( \\langle \\Sigma, E \\rangle \\) is correctly behaviorally subtyped. The inclusion \\( \\text{Mod}_{\\text{ord}}(E) \\subseteq \\text{Mod}_{\\text{nom}}(E) \\) holds in general, and, for any order-sorted \\( \\Sigma \\)-algebra \\( A \\), trivially \\( A^\\circ = A \\). Thus \\( \\text{Mod}_{\\text{ord}}(E) = \\text{Mod}_{\\text{ord}}^\\circ(E) \\subseteq \\text{Mod}_{\\text{nom}}^\\circ(E) \\). For the reverse inclusion, let \\( A^\\circ \\in \\text{Mod}_{\\text{nom}}^\\circ(E) \\), with \\( A \\in \\text{Mod}_{\\text{nom}}(A) \\). We must show that \\( A^\\circ \\) is also a model of \\( \\langle \\Sigma, E \\rangle \\). For this purpose consider any \\( \\forall H(t = t') \\in E \\), of type \\( V \\) that is necessarily visible, and let \\( a \\) be any \\( H \\)-environment of \\( A^\\circ \\). Then \\( a \\) is a virtual \\( H \\)-environment of \\( A \\). Since \\( \\langle \\Sigma, E \\rangle \\) is correctly behaviorally subtyped by assumption, \\( \\text{Mod}_{\\text{nom}}(E) \\) is correctly behaviorally subtyped and hence there is a \\( B \\in \\text{Mod}_{\\text{nom}}(E) \\) such that \\( A \\) is nominally VIS-reducible to \\( B \\) (see Appendix A, Def. A.1). Thus there is a (dynamic) \\( H \\)-environment \\( \\bar{b} \\) of \\( B \\) such that \\( \\bar{a} \\) and \\( \\bar{b} \\) are behaviorally equivalent and hence \\( t^A[\\bar{a}] = t^B[\\bar{b}] \\) and \\( t'^A[\\bar{a}] = t'^B[\\bar{b}] \\) since \\( \\forall H(t = t') \\) is visible. But \\( B \\) is a model of \\( \\langle \\Sigma, E \\rangle \\) and \\( \\bar{b} \\) is a dynamic environment. So \\( t^B[\\bar{b}] = \\bar{t'}^B[\\bar{b}] \\), and hence \\( t^A[\\bar{a}] = t'^A[\\bar{a}] \\). Thus \\( A^\\circ \\in \\text{Mod}_{\\text{nom}}(E) \\), and hence \\( \\text{Mod}_{\\text{ord}}(E) \\subseteq \\text{Mod}_{\\text{nom}}^\\circ(E) \\).\n\nAssume now that \\( \\text{Mod}_{\\text{nom}}^\\circ(E) = \\text{Mod}_{\\text{ord}}(E) \\). Let \\( A \\in \\text{Mod}_{\\text{nom}}(E) \\). Then by assumption \\( A^\\circ \\) is a model of \\( \\langle \\Sigma, E \\rangle \\). Since every \\( H \\)-environment \\( \\bar{a} \\) of \\( A \\) is automatically a dynamic \\( H \\)-environment of \\( A^\\circ \\), \\( A \\) is nominally VIS-behaviorally reducible to \\( A^\\circ \\) by the identity relation on environments. So \\( \\text{Mod}_{\\text{nom}}(E) \\), and hence \\( \\langle \\Sigma, E \\rangle \\), are correctly behaviorally subtyped (Def. A.1). \\( \\square \\)\n\n**Corollary 7.2.** Let \\( \\langle \\Sigma, E \\rangle \\) be an equational specification. The following are equivalent.\n\n(i) \\( \\langle \\Sigma, E \\rangle \\) is correctly behaviorally subtyped;\n\n(ii) For every equation \\( \\forall H(t = t') \\) over \\( \\Sigma, E \\models_{\\text{nom}} \\forall H(t = t') \\) iff \\( E \\models_{\\text{ord}} \\forall H(t = t') \\);\n\n(iii) For every equation \\( \\forall H(t = t') \\) over \\( \\Sigma, E \\models_{\\text{nom}} \\forall H(t = t') \\) iff \\( E \\models_{\\text{sub}} \\forall H(t = t') \\).\n\n**Proof.** The equivalence of (i) and (ii) is just a restatement of Theorem 7.1 in terms of nominal and order-sorted consequence (Def. 2.17). The equivalence of (ii) and (iii) follows immediately from the completeness and soundness theorem for equational logic with subtypes (Thm. 2.19). \\( \\square \\)\nIf \\( \\langle \\Sigma, E \\rangle \\) is correctly behaviorally subtyped then adding the subsumption rule to the equational logic does not allow one to prove any more equations. Conversely, any equational specification extended by subsumption is automatically behaviorally correctly subtyped. This observation also has a proof-theoretic formulation: if the subsumption rule is admitted, then the identity system \\( \\{c_{S,T}\\} \\), where \\( c_{S,T}[x_S:S] = x_S \\) is a coercion system.\n\n7.2. A deductive system for behavioral equivalence. As has been observed, the relation of behavioral provability \\( \\vdash_{\\text{beh}} \\) is not in general “inductive” in the sense of being recursively enumerable, but rather “coinductive”. Its coinductive nature can be expressed in various ways: compare Cor. 3.8, Thm. 3.10, and Cor. 3.13.\n\nIt would be valuable to find useful criteria for determining when formal behavioral equivalence is actually inductive in the above sense; more specifically, when can it be given by an equational specification? Considerable attention has been paid to this problem in the literature [3, 7, 33, 34, 35].\n\nThe following theorem is one of the main results on behavioral consequence; see [15, Theorem 25] where it is viewed as a another form of coinduction. It can be obtained as a corollary of an analogous characterization theorem for the more general notion of behavioral equivalence between environments described in Appendix A; see [22, Corollary 3.13] and also [23, Corollary 4.14]. However it can also be obtained with little difficulty directly from the definition of behavioral equivalence.\n\n**Theorem 7.3.** For every \\( \\Sigma \\)-algebra \\( A \\), the behavioral equivalence relation \\( \\mathcal{BE}(A) \\) is the largest VIS-identical homomorphic standard relation between \\( A \\) and itself.\n\nIn order to show that two objects \\( a \\) and \\( a' \\) of the same hidden type are behavioral equivalent it is sufficient to find some VIS-identical homomorphic standard relation on \\( A \\) that relates \\( a \\) and \\( a' \\). Using this method directly to show that an equation \\( \\forall H(t = t') \\) is a behavioral consequence of an equational specification \\( \\langle \\Sigma, E \\rangle \\) is more of a challenge: one must find, for every model \\( A \\) of \\( E \\) and every \\( H \\)-environment \\( \\bar{a} \\), a VIS-identical homomorphic relation that relates \\( t^A(\\bar{a}) \\) and \\( t'^A(\\bar{a}) \\). Practically speaking, this can only be done by exhibiting a system of visible equations that explicitly define the homomorphic relation uniformly for all models and \\( H \\)-environments. Corollary 3.8 actually provides such a system, namely the local contexts. We call a set of local contexts that alone suffices to define behavioral equivalence a **cobasis** for an equational specification \\( \\langle \\Sigma, E \\rangle \\). (A closely related notion is introduced in [33] under the same name.) If the specification has a finite cobasis then behavioral consequence is clearly inductive. For example, it is easy to see from the discussion in Example 3.9 that in order to verify than an equation is a behavioral consequence of the specifications \\( E_{cp} \\) and \\( E_{cpt} \\) it suffices to consider only the two local contexts \\( x(z) \\) and \\( y(z) \\).\n\nAn analogue of Theorem 7.3 is presented in [22] for the more general notion of behavioral equivalence between environments. (See [23, Corollary 3.13] for a formulation of the result that more closely resembles that of Theorem 7.3.) There is a proof theory for this more general notion of behavioral equivalence that parallels that for behavioral equivalence presented in Section 3 and which leads to proof-theoretic characterizations similar to Corollary 3.8, Theorem 3.10, and Corollary 3.13. It is problematic as to how useful this is for the specification of correct behavioral subtyping.\n8. Related Work\n\nIn regard to the material on behavioral equivalence in the context of equational specifications that we present here, the most closely related work in the literature is that Goguen et al. on hidden algebra [15, 16] (see also [14, 33, 34]). Much of the material in Sections 2 and 3 can be found in some form in at least one these papers. However our development is proof-theoretic while that of hidden algebra is mainly model-theoretic. The characterization of behavioral equivalence given in Theorem 7.3 can be found in [15, Theorem 25]. Corollary 3.8 is closely related to the notion a cobasis for an equational specification considered in [33]. Theorem 3.10 and Corollary 3.13 seem to be new.\n\nThe genesis for behavioral equivalence in hidden algebra seems to be Reichel [31]. The idea of behavioral equivalence, in the guise of logical equivalence, as the largest congruence satisfying a certain property can be traced back to the process of forming the Lindenbaum-Tarski algebra of the classical propositional calculus by Tarski [38]. A logical analog of Theorem 7.3 can be found in [36]. Subsequently these ideas formed the basis of abstract algebraic logic [4, 8, 12, 30].\n\nThe dichotomy between behavioral equivalence as a relation between objects and between environments seems to be novel, although elements of the latter (in the form of homomorphic generalized relations) can be found in [37] in the context of type theory. As mentioned above Theorem 7.3 is a consequence of a similar result for the environment version of behavioral equivalence in [22]. The latter is just one result in a general theory of behavior and realization that is developed in [22]. In [23] it is applied to obtain an algebraic completeness and soundness theorem for the notion of correct behavioral subtyping based on environment behavioral equivalence. Theorem 7.3 can be applied in a similar way to give an analogous completeness and soundness theorem for a more restricted notion of correct behavioral subtyping that is based on the behavioral equivalence of objects. The algebraic soundness theorem (Theorem 5.5) that serves as the principal lemma for the main result of the present paper (Theorem 5.6) is a consequence of both of these theorems, since object behavioral equivalence implies behavioral equivalence of environments in a natural sense. However, Theorem 7.1 and Corollary 7.2 suggest that behavioral equivalence of environments is the more natural of the two.\n\nTechniques for proving correct object behavioral subtyping have been studied by several authors [2, 5, 9, 10, 21, 24, 25, 26]. While most of these authors have studied the soundness of their techniques, to the best of our knowledge none have studied their completeness.\n\nIn earlier work [21] we showed that the use of nominal standard simulations as described above is sound for correct behavioral subtyping based on environment behavioral equivalence. However, more recently we showed that this technique is complete only for term-generated specifications and for specifications that do not use multiple dispatch [23].\n\nWe have observed that behavioral equivalence can be viewed as a device for introducing the notion state transitions into the algebraic theory of ADTs. Pure state transition systems constitute an important alternative to algebras as a basis for the semantics of OO languages. Gordon and Rees [18] investigate behavioral equivalence and its formalization in the context of $\\text{Ob}_{1<\\mu}$, Abadi and Cardelli’s single dispatch first-order calculus of objects with subtyping and with rewriting rules [1]. In this calculus data elements are identified with programs, i.e., expressions of the calculus, and logical equivalence (equality) is defined\nas reduction to the same normal form. Gordon and Rees define two programs to be \\textit{contextual equivalent} (their interpretation of behavioral equivalent) if, whenever they are placed in a larger boolean-valued program, the resulting programs either both converge or both diverge. \\textit{Bisimulation} is defined in terms of a transition system with the programs as states; here the fact that the calculus is single dispatch plays an essential role. Analogues of the algebraic completeness theorem for unary signatures (Thm. A.3) and the proof-theoretic soundness theorem (Thm. 5.6) are obtained, and the limitations of the method of bisimulation are pointed out; these turn out to be similar to the problems with coercion discussed above. One advantage of our work compared with Gordon and Rees’s is that our theory is not limited to single dispatch languages. There seems to be no analogue in their work of the notion of a local context and the refinement of the process of verifying correct behavioral subtyping that it leads to.\n\n9. Conclusions\n\nCoercion can be an effective way of verifying that an equational specification is correctly behaviorally subtyped, provided there is an effective method of verifying behavioral consequence. We studied one such method, local contexts, that seem to work well in many cases. But there can be no general method of this kind because in general there is no effectively computable procedure for verifying behavioral consequence.\n\nCoercion does not form a complete method for showing correct behavioral subtyping however since there is an example of an equational specification that is correctly behaviorally subtyped but has no coercion system. Moreover, the specification does use multiple dispatch, so the incompleteness does not result from the use of multiple dispatch. Furthermore, restriction to term-generated specifications does not give a completeness result for the coercion method.\n\nEquational logic with subsumption cannot cannot be used for the purpose of verifying correct behavioral subtyping because its models are essentially all order-sorted and order-sorted classes of models are automatically correctly behaviorally subtyped.\n\nAppendix A. Model Theory of Correct Behavioral Subtyping\n\nThe following is taken from sections 4 and 5 of [23].\n\nLet $A$ and $B$ be $\\Sigma$-algebras with the same carrier sets for their visible types. Let $H = \\langle x_1: T_1, \\ldots, x_n: T_n \\rangle$ be a type context over $\\Sigma$. Virtual $H$-environments $\\bar{a}$ and $\\bar{b}$ in $A$ and $B$, respectively, are said to be \\textit{VIS-behaviorally equivalent} if, for every $H$-term $t(x_1: T_1, \\ldots, x_n: T_n): V$ of visible type $V$, $t^A[\\bar{a}] = t^B[\\bar{b}]$.\n\n$A$ is \\textit{nominally VIS-behaviorally reducible to} $B$ if, for each type context $H$ and each virtual $H$-environment $\\bar{a}$ in $A$, there exists a dynamic $H$-environment $\\bar{b}$ in $B$ such that $\\bar{a}$ and $\\bar{b}$ are VIS-behaviorally equivalent.\n\nNote that if $A$ is order-sorted, then $A$ is nominally VIS-behaviorally reducible to itself, since every $H$-environment is is dynamic.\n\n\\textbf{Definition A.1} ([23]). Let $\\langle \\Sigma, E \\rangle$ be an equational specification. A class $\\mathcal{M}$ of VIS-categorical models of $\\langle \\Sigma, E \\rangle$ is \\textit{correctly behaviorally subtyped} if every $A \\in \\mathcal{M}$ is nominally VIS-behaviorally reducible to some $B \\in \\mathcal{M}$.\n\n\\square\nNote that the models $A$ and $B$ in the above definition can be equal. The idea here is that the correct subtyping means that the objects of subtypes behave just like objects of supertypes, and that the behavior of a virtual environment of $A$ is determined by the pattern of values it returns under all observations.\n\nA.1. Proof of the Algebraic Soundness Theorem. The proof of this theorem requires the following lemma (whose proof is by induction).\n\n**Lemma A.2** ([22, 23]). Let $A$ and $B$ be $\\Sigma$-algebras and assume $R$ is a nominal standard simulation of $B$ by $A$. Let $T$ and $(S_1, \\ldots, S_n) \\subseteq (T_1, \\ldots, T_n)$ be types. Then for all $\\Sigma$-terms $t[x_1:T_1, \\ldots, x_n:T_n];T$,\n\n$$(a_1, \\ldots, a_n) R_{T_1} \\times \\cdots \\times R_{T_n} \\langle b_1, \\ldots, b_n \\rangle \\text{ implies } t^A[a_1, \\ldots, a_n] R_T t^A[b_1, \\ldots, b_n]. \\quad \\square$$\n\nRecall that the algebraic soundness theorem itself reads as follows.\n\n**Theorem 5.5** (Algebraic Soundness Theorem [23]). Let $\\langle \\Sigma, E \\rangle$ be an equational specification, and let $\\text{Mod}_{\\text{Nom}}(E)$ be VIS-categorical. If for every $A \\in \\text{Mod}_{\\text{Nom}}(E)$ there exists a $B \\in \\text{Mod}_{\\text{Nom}}(E)$ and a nominal standard simulation of $B$ by $A$, then $\\langle \\Sigma, E \\rangle$ is correctly behaviorally subtyped.\n\n**Proof.** Let $A, B \\in \\text{Mod}_{\\text{Nom}}(E)$, and let $R = \\langle R_T \\subseteq A^\\circ_T \\times B^\\circ_T : T \\in \\text{TYPE} \\rangle$ be a nominal standard simulation of $B$ by $A$. Let $H = \\langle x_1:T_1, \\ldots, x_n:T_n \\rangle$ be a type context over $\\Sigma$ and let $\\bar{a} = a_1, \\ldots, a_n$ be a virtual $H$-environment in $A$. Then $\\bar{a} \\in A_{S_1} \\times \\cdots \\times A_{S_n}$ for some $S_1, \\ldots, S_n \\subseteq T_1, \\ldots, T_n$. Since $R$ is nominal, there exists a dynamic $H$-environment $\\bar{b} = b_1, \\ldots, b_n$ such that $\\bar{a} R_{T_1} \\times \\cdots \\times R_{T_n} \\bar{b}$. We will show that $\\bar{a}$ is VIS-behaviorally equivalent to $\\bar{b}$. For this purpose let $t[x_1:T_1, \\ldots, x_n:T_n];V$ be an $H$-term of visible type $V$. By Lem. A.2\n\n$$t^A[\\bar{a}] R_V t^B[\\bar{b}].$$\n\nHence $t^A[\\bar{a}] = t^B[\\bar{b}]$, since $R$ is VIS-identical.\n\nSince $\\bar{a}$ is VIS-behaviorally equivalent to $\\bar{b}$, $\\text{Mod}_{\\text{Nom}}(E)$ is correctly behaviorally subtyped, and hence, by definition, $\\langle \\Sigma, E \\rangle$ is correctly behaviorally subtyped. \\quad \\square\n\nA.2. Algebraic Completeness for Unary Signatures. For standard simulations, there is no algebraic completeness theorem that corresponds to the algebraic soundness theorem. A equational specification, call it $\\langle \\Sigma_1, E_1 \\rangle$, is given in our previous work [23] that is correctly behaviorally subtyped but has a restricted model $A_1$ such that $A_1$ is not nominally behaviorally reducible to any restricted model of $\\langle \\Sigma_1, E_1 \\rangle$, including itself. On the other hand, in the same previous work we show that no specification of this kind can exist if the signature in question has only unary methods. Thus the method of nominal standard simulation is complete for correct behavioral subtyping if only unary methods are allowed. We restate the theorem here.\n\n**Theorem A.3** (Algebraic Completeness Theorem for Unimethod Signatures, [23]). Let $\\Sigma$ be signature with subtyping that has only unary methods. Let $\\langle \\Sigma, E \\rangle$ be an equational specification such that $\\text{Mod}_{\\text{Nom}}(E)$ is VIS-categorical. If $\\langle \\Sigma, E \\rangle$ is correctly behaviorally subtyped, then for every $A \\in \\text{Mod}_{\\text{Nom}}(E)$ there exists a $B \\in \\text{Mod}_{\\text{Nom}}(E)$ and a nominal standard simulation of $B$ by $A$. \\quad \\square\nA similar result holds for equational specifications for which each restricted model is term-generated [22, 23].\n\n**References**\n\n\nDepartment of Computer Science, Iowa State University, Ames, IA 50011-1041, USA, E-mail address: leavens@cs.iastate.edu\n\nDepartment of Mathematics, Iowa State University, Ames, IA 50011, USA E-mail address: dpigozzi@iastate.edu"}}},{"rowIdx":96,"cells":{"id":{"kind":"string","value":"4ea6fb41a7e9412aae5720b87140f9cf3885a2e8"},"text":{"kind":"string","value":"Notices\n\n© 2014 Progress Software Corporation and/or its subsidiaries or affiliates. All rights reserved.\n\nThese materials and all Progress® software products are copyrighted and all rights are reserved by Progress Software Corporation. The information in these materials is subject to change without notice, and Progress Software Corporation assumes no responsibility for any errors that may appear therein. The references in these materials to specific platforms supported are subject to change.\n\nBusiness Making Progress, Corticon, DataDirect (and design), DataDirect Cloud, DataDirect Connect, DataDirect Connect64, DataDirect XML Converters, DataDirect XQuery, Easy!, Fathom, Making Software Work Together, OpenEdge, Powered by Progress, Progress, Progress Control Tower, Progress RPM, Progress Software Business Making Progress, Progress Software Developers Network, Rollbase, RulesCloud, RulesWorld, SequeLink, SpeedScript, Stylus Studio, and WebSpeed are registered trademarks of Progress Software Corporation or one of its affiliates or subsidiaries in the U.S. and/or other countries. AccelEvent, AppsAlive, AppServer, BusinessEdge, DataDirect Spy, DataDirect SupportLink, , Future Proof, High Performance Integration, Modulus, OpenAccess, Pacific, ProDataSet, Progress Arcade, Progress Pacific, Progress Profiles, Progress Results, Progress RFID, Progress Progress Software, ProVision, PSE Pro, SectorAlliance, SmartBrowser, SmartComponent, SmartDataBrowser, SmartDataObjects, SmartDataView, SmartDialog, SmartFolder, SmartFrame, SmartObjects, SmartPanel, SmartQuery, SmartViewer, SmartWindow, WebClient, and Who Makes Progress are trademarks or service marks of Progress Software Corporation and/or its subsidiaries or affiliates in the U.S. and other countries. Java is a registered trademark of Oracle and/or its affiliates. Any other marks contained herein may be trademarks of their respective owners.\n\nPlease refer to the Release Notes applicable to the particular Progress product release for any third-party acknowledgements required to be provided in the documentation associated with the Progress product.\n\nThe Release Notes can be found in the OpenEdge installation directory and online at:\n\nFor the latest documentation updates see OpenEdge Product Documentation on Progress Communities: (https://community.progress.com/technicalusers/w/openedgegeneral/1329.openedge-product-documentation-overview.aspx).\n\nDecember 2014\n\nLast updated with new content: Release 11.5.0\n# Table of Contents\n\n**Preface**\n\n- About this documentation.................................................................9\n- User types........................................................................................9\n- Information on documentation..........................................................10\n- Conventions used in this manual.......................................................11\n- Product support contact information................................................12\n\n**Chapter 1: OpenEdge Business Process Server overview**\n\n- Business Process Server components.............................................16\n- How Business Process Server works...............................................18\n- Business Process Server user types..................................................20\n\n**Chapter 2: Getting started**\n\n- Logging in to Business Process Portal.............................................22\n- Enabling multi-tab support...............................................................23\n- Using themes....................................................................................23\n- Exploring Business Process Portal..................................................24\n - Business Process Portal page layout.............................................24\n - Business Process Portal keyboard shortcuts.................................25\n - Using filter bars.............................................................................26\n - Global filters...............................................................................27\n - Sorting a column...........................................................................27\n - Grid Search..................................................................................28\n - Rearranging column order............................................................29\n - Navigating through the list.............................................................29\n - Drilling down................................................................................30\n - Selecting and clearing rows..........................................................31\n - Printing.........................................................................................32\n- Getting support................................................................................32\n- Accessing help.................................................................................32\n- Finding Business Process Server details........................................32\n- Logging out of Business Process Portal..........................................32\n\n**Chapter 3: Basic Operations**\n\n- Specifying a Date..............................................................................35\n- Searching Users...............................................................................36\n- Searching Group..............................................................................37\nPreface\n\nFor details, see the following topics:\n\n• About this documentation\n• User types\n• Information on documentation\n• Conventions used in this manual\n• Product support contact information\n\nAbout this documentation\n\nThis guide is part of the documentation set for Progress OpenEdge Business Process Server.\n\nUser types\n\nProgress OpenEdge Business Process Server is a business process management system that can be used by the following types of users:\n\n<table>\n<thead>\n<tr>\n<th>User type</th>\n<th>Responsibilities</th>\n</tr>\n</thead>\n</table>\n**User type** | **Responsibilities**\n---|---\nManager | Responsible for automating business processes in a particular business domain. Business Process Portal's Management module serves as the primary interface to Business Process Server for the Manager, enabling the manager to monitor, analyze, and control business processes. Also uses the Business Process Modeler for modeling and simulation.\n\nApplication Developer | Responsible for creating customized applications for implementing business processes and developing interfaces associated with tasks. Application developers may work closely with Managers to define the requirements of an application, and determine the business processes.\n\n\n---\n\n**Information on documentation**\n\nThis documentation includes information for the entire range of Progress OpenEdge Business Process Server users. In the following table, we recommend the guides that are most relevant to each type of user.\n\n<table>\n<thead>\n<tr>\n<th>If you are the ...</th>\n<th>Read the ...</th>\n</tr>\n</thead>\n</table>\n*First Steps Guide* \n*Terminology Guide* |\n| Manager | *Business Process Portal Manager's Guide* \n*Business Process Portal User's Guide* \n*Terminology Guide* |\n## Conventions used in this manual\n\nThis document uses the following conventions and terminology notations.\n\n<table>\n<thead>\n<tr>\n<th>Convention (styles and terms)</th>\n<th>Purpose</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>bold</strong></td>\n<td>Indicates titles of command buttons, check boxes, options, lists, dialog boxes, and portal page names.</td>\n</tr>\n<tr>\n<td><strong>file path</strong></td>\n<td>Indicates folder paths and file names.</td>\n</tr>\n</tbody>\n</table>\n\n---\n\nFor the latest Business Process Server documentation updates, see OpenEdge Product Documentation on PSDN (http://communities.progress.com/pcom/docs/DOC-16074).\n### Purpose Convention (styles and terms)\n\n<table>\n<thead>\n<tr>\n<th>Convention (styles and terms)</th>\n<th>Purpose</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><em>italic</em></td>\n<td>Indicates book titles.</td>\n</tr>\n<tr>\n<td>monospace</td>\n<td>Represents code segments or examples.</td>\n</tr>\n<tr>\n<td>backward slash ""</td>\n<td>Indicates the path in Windows environment. For UNIX environment, replace with forward slash "/"</td>\n</tr>\n<tr>\n<td>OEBPS_HOME or %OEBPS_HOME%</td>\n<td>Represents the installation folder of Business Process Server, C:\\Progress\\OpenEdge\\oebpm\\server.</td>\n</tr>\n<tr>\n<td>STUDIO_HOME or %STUDIO_HOME%</td>\n<td>Represents the installation folder of OpenEdge BPM components, C:\\Progress\\OpenEdge\\oebpm\\studio.</td>\n</tr>\n<tr>\n<td>JBOSS_HOME or %JBOSS_HOME%</td>\n<td>Represents the installation folder of JBOSS server, C:\\Progress\\OpenEdge\\oebpm\\jboss.</td>\n</tr>\n</tbody>\n</table>\n\n### Product support contact information\n\nIf the product documentation does not provide a solution to your specific issue, or if you need clarification on the issue, then contact our Product Support team. You can contact the team through the Internet, telephone, or postal mail, as per the details provided in Table 1 on page 12.\n\n**Table 1: Product Support Contact Information**\n\n<table>\n<thead>\n<tr>\n<th>To contact by</th>\n<th>Use</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Web site</td>\n<td><a href=\"http://progresslink.progress.com/supportlink\">http://progresslink.progress.com/supportlink</a></td>\n</tr>\n<tr>\n<td></td>\n<td>If you are an existing customer, then you can log in to the above site for product support. If you are a first time user, then you need to create an account first.</td>\n</tr>\n</tbody>\n</table>\n| Telephone\\(^1\\) | 1-781-280-4999 for US, Latin America and Canada \n1-781-280-4543 for the Product Support Fax Line |\n| Postal Address\\(^1\\) | Progress Software Corporation \n14 Oak Park Drive \nBedford, MA 01730, USA. |\n\nTo enable us to quickly answer your questions, please provide the following information:\n\n- Your name, installation site address and the license key for Business Process Server software.\n- Your Business Process Server version and build number.\n\n\\(^1\\) For support telephone numbers and offices in your region, visit the support web site above. This contact information is for customer support only.\n• Your operating system, application server and browser, with version and service pack details, if any.\n\n• Your database management system and version, and information on JVM and JDBC used.\nOpenEdge Business Process Server overview\n\nProgress Software Corporation is a leading global provider of automated business process management solutions. The company’s product, Progress OpenEdge Business Process Server (henceforth referred to as Business Process Server or BP Server), is a comprehensive business process management platform, which enables companies to quickly transform their business processes into flexible and manageable Web applications, distributed over intranets, extranets, and the Internet.\n\nBusiness Process Server addresses every stage in the business life cycle: define, integrate, publish, monitor, analyze, improve, and control. By adopting an end-to-end approach, Business Process Server incorporates all the key elements required to meet the ever-changing demands of e-business while ensuring e-business success. By providing integrated management tools, Business Process Server lets you monitor operations proactively, modifying automated processes dynamically based on changing external operations online. An overview of a typical automated business process management solutions is shown in Figure 1 on page 16.\nFor details, see the following topics:\n\n- Business Process Server components\n- How Business Process Server works\n- Business Process Server user types\n\n**Business Process Server components**\n\nBusiness Process Server is a suite of integrated components that enables you to easily build intranet, extranet, and Internet applications and manage your e-business. Business Process Server consists of the following components as in Figure 2 on page 17:\nTable 2: Business Process Server components\n\n<table>\n<thead>\n<tr>\n<th>Component</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Business Process Portal Home</td>\n<td>The Home module of Business Process Portal is the primary interface for application users, enabling them to interact with Business Process Server applications. Users can complete entries to various tasks and applications, and link to the support infrastructure required to complete these tasks.</td>\n</tr>\n<tr>\n<td>Business Process Portal Management</td>\n<td>The Management module enables managers to query, report on, and control processes and resources, visible only to the managers.</td>\n</tr>\n<tr>\n<td>Business Process Portal Administration</td>\n<td>The Administration module enables Business Process Server Administrators to modify configuration parameters, manage user or group access control, and install or uninstall Business Process Server applications.</td>\n</tr>\n<tr>\n<td>Web services</td>\n<td>This component allows application developers to: publish their applications as Web services, and find and convert other available Web services on the Internet into Business Process Server applications.</td>\n</tr>\n<tr>\n<td>BPM Webflow</td>\n<td>This component provides a framework for developing and implementing Web-enabled workflow applications.</td>\n</tr>\n<tr>\n<td>Component</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>------------------------------------------------</td>\n<td>-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Progress Developer Studio for OpenEdge</td>\n<td>This is the primary application development tool for Business Process Server, which provides an Eclipse-based integrated development environment in which users can create BPM projects, processes, Web applications, and rule files.</td>\n</tr>\n<tr>\n<td>Business Process Modeler</td>\n<td>This tool is used to design templates for basic business processes, and to run simulations of processes and individual worksteps.</td>\n</tr>\n<tr>\n<td>BP Server</td>\n<td>This is a flexible, lightweight, scalable workflow process engine for intranets, extranets, and the Internet.</td>\n</tr>\n<tr>\n<td>BPM Events</td>\n<td>This open, event-driven rule engine is used to formulate and enforce policies in business applications.</td>\n</tr>\n</tbody>\n</table>\n\n**How Business Process Server works**\n\nThe following figure provides an overview of the interaction between Business Process Server components.\n\n**Figure 3: How Business Process Server works**\n\n\nThe following explanations correspond to the labels shown in the above figure, and describe how the components operate.\n\n1. Progress Developer Studio for OpenEdge and Business Process Modeler provide an integrated development environment (IDE) for Business Process Server, where you can design and publish business processes. The application developer designs a process template (with the \".spt\" or \"*.swt\" extension) in the IDE that reflects the business flow and other business process requirements. Business rules for the process template can be defined using the Rule Editor, a BPM Events component that is launched with Progress Developer Studio for OpenEdge.\n\n\n3. Once the process template is defined, Business Process Server Administrators use the Administration module to install the business process on the BP Server. Administrators can also configure Business Process Server components, manage user or group access control, and publish Business Process Server applications as Web services. Once installed, users access applications through servlets that pass the requests over an RMI/IIOP connection to the BP Server within an EJB Container.\n\n4. The EJB Container provides a runtime environment that executes and manages Java-based program components that run on the server side of a client/server network. Within the EJB Container are the BP Server and BPM Events server.\n\n5. The BP Server writes events to event tables in the database. Each Business Process uses JDBC to connect to database server as well as store events in the database. Within the BP Server, BPM Process Store uses JDBC to connect to the database server process and retrieve the events deposited by the BP Server process. BPM Process Store interprets the events and populates the process tables. These populated tables are used by Business Process Portal modules.\n\n6. Once the process template is installed as a Business Process Server application, application users can use the Home module to do the following:\n - Access applications\n - Obtain information to perform their tasks\n - Launch the application to start process instances from the BP Server\n\n7. Once the process template is installed as an Business Process Server application, managers can use the Management module (if they have access privileges) to monitor execution of process instances and create reports. Servlets receive requests from managers and pass them onto the BP Server over an RMI/IIOP connection. Managers use the Report Builder to define management reports that retrieve information through JDBC to the database server.\n\n8. BPM Events is a rule-based event or message processing server that loads application rules and executes them against the BP Server and/or external events or messages. This server persists data in the database for recovery and with the help of JDBC connects to the database.\n\n9. Managed Adapters exchange information between Business Process Server applications and external applications by converting Business Process Server-specific protocol to the protocol of an external system such as a database or ERP system. When users add a Managed Adapter to a work step, they can define complex mapping between Business Process Server dataslots and adapter inputs or outputs of the external application. At runtime when the work step is executed, the Managed Adapter sets the adapter inputs and configuration, and maps the outputs to the appropriate output dataslots.\n10. BPM Webflow is a run-time component that executes the presentation flows. This component provides a Model, View, Controller (MVC) paradigm for developing presentation flow-based applications and executing them in a Web container.\n\n11. Business Process Servers Web services component allows BP Server applications to be published as Web services.\n\n\nBusiness Process Server user types\n\nThere are four user types within Business Process Server, Application users, Managers, Application developers, Business Process Server administrators.\n\nUser types\n\nEach Business Process Server user type is defined below:\n\n• **Application users** — Application Users use Business Process Server applications to coordinate specific business tasks with another department within their company, with another company within their organization, and/or with a business partner in another organization. The Home module in Business Process Portal serves as the primary interface in which Application Users run Business Process Server applications.\n\n• **Managers** — Managers are typically experts in a particular business domain, such as quality assurance or human resources. They might need to work with managers from other groups in automating some of the business procedures that these groups share. The Management module in Business Process Portal serves as the primary Business Process Server interface for business managers to coordinate and integrate business processes, enabling them to exchange information with one another, and to share functionality over such standard communication channels as the Internet or e-mail.\n\n• **Application developers** — Application developers are responsible for analyzing business processes and developing interfaces associated with creating tasks or processes. Application developers are often not domain experts themselves, but work closely with Managers to define business processes and determine the requirements of an application. Application developers use Progress Developer Studio for OpenEdge or Business Process Modeler to define the business process; the resulting process template file is tested, simulated, published, and run as a Business Process Server application.\n\n• **Business Process Server administrators** — Business Process Server administrators are responsible for configuring Business Process Server components, managing user or group profiles and access control, and installing or uninstalling Business Process Server applications. The Administration module in Business Process Portal serves as the primary interface for Business Process Server Administrators to administer applications.\n\nAll Business Process Server user types can communicate by using one or more Business Process Server applications. They can also communicate with external applications.\nGetting started\n\nBusiness Process Server provides primary Web-based user interface in the form of Business Process Portal. It is a complete portal through which you can interact with Business Process Server applications.\n\nWhen you log into Business Process Portal, it displays the Home module tab for all users, irrespective of your user type and your user permissions. As an application user, you can display and modify tasks assigned to you, and manage your preferences. Depending on your user type and permissions, you can view and access other module tabs namely, Management and Administration.\n\nIf you have Manager rights, then the Management module is also available to you, where you can query, report, and control processes and resources for users.\n\nIf you also have administrative rights, in the Administration module, then you can modify configuration parameters controlling Business Process Server operations, manage components, and install/uninstall applications.\n\n**Note:** Though all modules are shown to you in the figures in this guide, you can view and access only those modules for which you have access rights.\n\n<table>\n<thead>\n<tr>\n<th>Table 3: Business Process Portal modules</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Module name</strong></td>\n</tr>\n<tr>\n<td>Home</td>\n</tr>\n</tbody>\n</table>\nThis chapter describes how to log into and out of Business Process Portal, the screen layout, and how to explore the Home module’s interface. As the interface is uniform for all modules, this information is helpful for other modules also. For details, see the following topics:\n\n- Logging in to Business Process Portal\n- Enabling multi-tab support\n- Using themes\n- Exploring Business Process Portal\n- Getting support\n- Accessing help\n- Finding Business Process Server details\n- Logging out of Business Process Portal\n\n### Logging in to Business Process Portal\n\nTo access Business Process Portal and use it, you need to log in to it. Your Business Process Server administrator typically adds you as a new Application User, and assigns you a User Name and Password. To log in to Business Process Portal, you need to use this User Name and Password.\n\n**To log in to Business Process Portal:**\n\n1. Start the Login page according to your platform:\n\n<table>\n<thead>\n<tr>\n<th>Using . . .</th>\n<th>Perform the following . . .</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Windows 2003/XP</td>\n<td>From the Start menu, choose Programs > Progress > OpenEdge > BP Server > BP Servers > Start Business Process Server if you are using the installation machine (For windows only). Otherwise enter <a href=\"http://machine_name.domain.com:port_number/bpmportal/login.jsp\">http://machine_name.domain.com:port_number/bpmportal/login.jsp</a> in your browser.</td>\n</tr>\n<tr>\n<td>UNIX</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nThe Login page is displayed as shown in Figure 4 on page 23.\nFigure 4: Business Process Portal Login page\n\nNote: If you are using a theme other than the default one, then the screens will look different than shown in this document. For more details, see Using themes on page 23.\n\n2. Type your User Name and Password\n3. Click Login.\n\nBusiness Process Portal displays the Task List page. As a typical Application User, you will have access only to the Home module. Other modules to which you may have access are displayed along with Home, as additional tabs depending on your user type and user permissions.\n\nTip: You can change your password any time by using Home > Profile.\n\nEnabling multi-tab support\n\nBy default, Business Process Portal does not support multi-tab browsing. So, after having logged into the Portal, if you try to login again from another tab in the browser, the first instance of the Portal becomes invalid. This might causes several unexpected issues.\n\nTo avoid any such issues, you must enable the multi-tab support for Business Process Portal by adding the following line of code to the bpmportal.conf file at $DLC/oebpm/server/conf/ location:\n\n```\nbpmportal.relogin.or.continue = true\n```\n\nThis ensures that whenever you try to open the Business Process Portal, you are directed to any active session of the Portal, if available.\n\nUsing themes\n\nBusiness Process Server provides five predefined themes for Business Process Portal and for applications in the portal. Your Business Process Server administrator can select one of them. For more details, see Customization Guide.\nExploring Business Process Portal\n\nWhen you log in to Business Process Portal for the first time, you can see the default Home tab, with the My Task page listing tasks assigned to you.\n\n**Note:** Use the Profile menu to select the language you prefer and use the Preferences menu to select a filter that sets the page’s display. After configuring the Home tab, your selections are displayed the next time you log in to Business Process Portal.\n\nBusiness Process Portal page layout\n\nThe terminology used for a typical **Business Process Portal** page is explained below.\n\nThe following table describes the screen terminology used for Business Process portal.\n\n**Table 4: Business Process Portal page terminology**\n\n<table>\n<thead>\n<tr>\n<th>User interface elements</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Global links</td>\n<td>Located at the top right corner of every page such as Support or Help, these links are available at all times during the session. It also displays the welcome message for the user who has logged in.</td>\n</tr>\n<tr>\n<td>Module tabs</td>\n<td>For your convenience, features of different modules are grouped in sections. All features of a particular group are located in its own Module tab.</td>\n</tr>\n<tr>\n<td>Module menus</td>\n<td>Each tab has a set of specific menus. At the right side, a welcome message is displayed to the user.</td>\n</tr>\n<tr>\n<td>Page name</td>\n<td>This shows the current page name.</td>\n</tr>\n<tr>\n<td>Link trail</td>\n<td>This shows the pages you navigated through to reach the current page. You can click any link in the link trail and go back to that page. If you click a link in the link trail without first saving contents of the current page, then the data in the current page is not saved.</td>\n</tr>\n</tbody>\n</table>\nYour data is displayed in this area. Generally it is displayed in one of the following ways:\n\n- **Form:** This lets you interact with the portal. Typically, forms contain text boxes, check boxes, and options that help you enter data. Forms can be in read-only or editable mode depending upon the contents and access privileges.\n- **List:** This lets you view your data in a tabular format. Typically, lists contain filter bars, search options, and page controls that manage which data is displayed and how it should be displayed.\n\nThe commands that help you interact with the data are represented by buttons. Buttons that help you accomplish some task but do not change the data values are typically located below the link trail. The links (for instance, My Collaborative Tasks and Next Available Task) are located above the workspace, on the right side. Buttons that operate on the data (for instance, Complete and Reassign) shown in the current page and change their values, are located below the workspace.\n\n### Business Process Portal keyboard shortcuts\n\nBusiness Process Portal provides the following keyboard shortcuts to access its various module menus and menu options.\n\n#### Shortcuts\n\nThe following table lists the keyboard shortcuts available in Business Process Portal.\n\n#### Table 5: Keyboard shortcuts\n\n<table>\n<thead>\n<tr>\n<th>Module</th>\n<th>Keys</th>\n<th>Menu / Menu option</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Home</td>\n<td>CTRL+SHIFT+T</td>\n<td>My Tasks</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+M</td>\n<td>My Instances</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+S</td>\n<td>Applications</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+D</td>\n<td>Dashboard</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+O</td>\n<td>Profile</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+F</td>\n<td>Preferences > Filters</td>\n</tr>\n<tr>\n<td>Management</td>\n<td>CTRL+SHIFT+I</td>\n<td>Overview > Instances</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+A</td>\n<td>Overview > Applications</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+R</td>\n<td>Reports > My Reports</td>\n</tr>\n<tr>\n<td>Module</td>\n<td>Keys</td>\n<td>Menu / Menu option</td>\n</tr>\n<tr>\n<td>---------------------</td>\n<td>--------------</td>\n<td>----------------------------------</td>\n</tr>\n<tr>\n<td>CTRL+SHIFT+N</td>\n<td>Instance Manager > Instances</td>\n<td></td>\n</tr>\n<tr>\n<td>CTRL+SHIFT+K</td>\n<td>Instance Manager > Tasks</td>\n<td></td>\n</tr>\n<tr>\n<td>CTRL+SHIFT+W</td>\n<td>Instance Manager > Worksteps</td>\n<td></td>\n</tr>\n<tr>\n<td>CTRL+SHIFT+C</td>\n<td>Balanced Scorecard > Console</td>\n<td></td>\n</tr>\n<tr>\n<td>Administration</td>\n<td>CTRL+SHIFT+V</td>\n<td>System > Log Viewer</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+U</td>\n<td>User Management > Users</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+G</td>\n<td>User Management > Groups</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+Q</td>\n<td>User Management > Queues</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+P</td>\n<td>User Management > Permissions</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+E</td>\n<td>User Management > Delegate Settings</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+L</td>\n<td>Applications > BP Server</td>\n</tr>\n<tr>\n<td></td>\n<td>CTRL+SHIFT+Z</td>\n<td>Applications > BPM Webflow</td>\n</tr>\n</tbody>\n</table>\n\nYou can customize these shortcuts by adding a new one or changing an existing one as per your requirement. For more details, see the *Customization Guide*.\n\n### Using filter bars\n\nA filter allows you to reduce clutter and focus on the relevant data by displaying only selected data in the workspace.\n\n**To apply a filter using the Filter bar:**\n\n1. Specify values by either entering text in the provided text boxes or selecting them from the lists (Figure 5 on page 26).\n2. Click **Search**.\n\nThe combination of these values forms a filter.\n\n**Figure 5: Filter bar**\nGlobal filters\n\nBusiness Process Server now provides global filters for most common filtering conditions. They are:\n\nFilter names\n\n- Overdue Tasks\n- Tasks Due Today\n- Tasks Due This Week\n- Tasks Due This Month\n- Tasks Due This Quarter\n- Tasks Due This Year\n- Critical Priority Tasks\n- High Priority Tasks\n\nNote: You can select a global filter as your default filter from the Home > Profile menu. Alternately, you can use it as required.\n\nSorting a column\n\nIn the Home module, a downward pointing triangle beside the column header indicates that the listed items can be sorted on that column header.\n\nTo sort a column:\n\n1. Click the column to display the sorting options.\n Refer Figure 6 on page 27.\n\n Figure 6: Sorting options - Task list page\n\n2. Choose the required sorting option.\n - A downward pointing triangle beside the column header indicates that the items are sorted in descending order. To sort them in ascending order, click the column header again.\n - An upward pointing triangle beside the column header indicates that the items are sorted in ascending order.\nNote: From the Sorting options, you can choose only the required columns to be displayed and thus you can reduce the screen clutter.\n\nThe column sorting operation is performed differently in the Management and Administration modules.\n\n- A column header is underlined only when you move the mouse over the column name.\n- In the Management and Administration modules, if a column header is underlined, then you can click it to sort the listed items on that column header.\n\nRefer Figure 7 on page 28.\n\nFigure 7: Column sorting\n\nGrid Search\n\nThe Grid Search Text toolbar will allow you to search and highlight the given text in the current page of the grid. And this is enabled for all portal grids.\n\nFigure 8: Grid Search Text\n\n- The grid searching is done locally and there will not be any remote call for it.\n- The ‘Grid Search Text’ toolbar is available next to the paging toolbar of the grid by default.\n- The ‘Grid Search Text’ toolbar will be refreshed on the following actions.\n - Reloading or refreshing the page.\n - While paging the grid.\n\nGrid Toolbar Fields\n\n- Text box\n You can enter the search text in this field. The search functionality is executed on every change of this text box, so that it is not required to click search for start the searching process. All the occurrences of the given text are highlighted and the row containing the first occurrence is selected by default. A ‘clear’ button is displayed beside the text box which enables you to clear the text box. By default, this text box supports regular expressions. Therefore, if your search conforms with the regular expression syntax, then Business Process Portal considers it as a regular expression, and searches accordingly.\n\n- Previous Row and Next Row Buttons\nThese buttons are enabled only when given text is found in the grid, otherwise they are disabled. These buttons help you to navigate and select one of rows which is highlighted. Tool tips are configured to indicate the use case of these buttons.\n\n- **Match Case check box**\n You can use the ‘Match Case’ check box to enable case-sensitive search. By default, this check box is unchecked.\n\n- **Status Bar**\n The ‘Status Bar’ displays the number of occurrences or matches found. The icons ‘status OK’ and ‘error status’ indicate the status of the search.\n\n**Rearranging column order**\n\nYou can change the order in which the columns are displayed as per your requirement.\n\n**To change the order of columns:**\n\nDrag the column header and drop it on the column header which should succeed the selected column.\n\nThe new position of the selected column is indicated by two arrows.\n\nWhether a particular position is permissible or not is indicated by green check mark on the selected column.\n\nRefer Figure 9 on page 29.\n\n**Figure 9: Rearranging column order**\n\n\n\n**Note:** You can change the order of columns in this way only in the Home module.\n\n**Navigating through the list**\n\nThe paging controls allow you to navigate through pages of the current list. These controls are located immediately above and below the list.\n\nThe number of items to be displayed per page is specified by the Business Process Server administrator in the Administration module. For more details, refer to the \"Using the Portal Configuration Interface\" section of the Business Process Portal Administrator’s Guide. If the total number of items cannot be displayed in a page, then the exceeded items are displayed on the subsequent pages.\n\nRefer Figure 10 on page 30.\nNavigating through the pages in Home Module:\n\n- **First Page** control displays the first page\n- **Previous Page** control displays the previous page\n- **Next Page** displays the next page\n- **Last Page** displays the last page\n- You can directly display a particular page by specifying its page number in the **Page** text box and pressing the Enter key.\n\nYou can click the **Refresh** control to reload the current page.\n\nThe top right corner of the list shows the item numbers displayed on the current page out of the total number of items.\n\nThe paging controls in the Management and Administration modules are different.\n\nRefer Figure 11 on page 30.\n\n**Figure 11: Paging control**\n\nIn the Management and Administration modules, if the number of pages are 10 or less, then all page numbers up to the last page are displayed below the list.\n\nNavigating through the pages in Management and Administration modules:\n\n- You can click a page number to display the corresponding page.\n- If the number of pages is more than 10, then, click\n - **Next** helps to access the set of next 10 pages.\n - **Previous** helps to access the set of previous 10 pages.\n- The total at the far right of the paging controls represents the total number of items in the list across all pages.\n\n**Drilling down**\n\nIf more information is available about an item in the list, then such an item is displayed with a hyperlink.\n\nYou can click the hyperlink to drill down to the next level of data and view details of that item.\n\nRefer Figure 12 on page 31.\nSelecting and clearing rows\n\nTo select and clear rows:\n\n1. Perform either of the following to select rows:\n - You can select one or more rows of items from the list of items displayed on the current page by clicking their respective check boxes in the first column.\n - To select all rows in the current page, select the check box in the header row.\n\n Selected rows are indicated by different color.\n\n Refer Figure 13 on page 31.\n\nFigure 13: Rows\n\n2. Perform either of the following to clear rows:\n - To clear a particular row, click its check box again.\n - To clear all rows uncheck the header row, all selected rows in the page are cleared.\nPrinting\n\nThe Print icon () displays the contents of the current page in a printable format. You can use your browser’s print feature to print it.\n\nGetting support\n\nIf you do not find the solution to your problem in the product documentation, then you can contact the support team.\n\nTo contact Progress OpenEdge support team:\n\n1. Click Support from the global links.\n \n Your default mail tool is launched to send a mail to the support team.\n\n2. Add your query and send the mail.\n\nAccessing help\n\nYou can access online help from the global links.\n\nTo access online help:\n\n• Click Help from the global links.\n\nThe help is launched in a separate browser window.\n\nBusiness Process Portal provides context-sensitive help, displaying the help topic that is relevant to the current module.\n\nFinding Business Process Server details\n\nYou can find out details about the Business Process Server using, About from the global links.\n\nTo view Business Process Server details:\n\n• Click About from the Global links.\n\nIt displays the following details about Application Server, Database Type, Database Version, Business Process Server Version, and Build number in a pop-up window.\n\nYou need this information while contacting our support team.\n\nLogging out of Business Process Portal\n\nYou can log out of the Business Process Server using the global links.\nTo quit Business Process Portal:\n\n- Click **Logout** on the global links.\n\nAfter a successful logout, Business Process Portal automatically displays Business Process Portal **Login** page.\nBasic Operations\n\nThis chapter explains the basic operations you can perform while using Business Process Portal. You can perform some or all of these operations in various Business Process Portal screens. However, all these operations may not be available in each Business Process Portal screen. For details, see the following topics:\n\n- Specifying a Date\n- Searching Users\n- Searching Group\n- Working with attachments\n\nSpecifying a Date\n\nYou can specify a date by typing it in the various text boxes involving a Date (for example, Due Date, Start Date, End Date) or select using Select Date icon, which is generally located beside the Date text box.\n\nTo specify a date using Select Date icon, perform the following:\n\n1. Click the Select Date icon ( thở) beside the Date box.\n For a blank Date box, the Select Date window displays the current month's calendar and by default, highlights today's date and the current time.\n Refer Figure 14 on page 36.\n2. You can select a date by performing one or more of the following operations from **Select Date** dialog:\n\n- To select a date from the displayed month, click the desired date. To select today's date, click **Today**.\n- To display the calendar for another month, use the single arrows provided above the days of the week. Click the arrow pointing right for the next month, or the arrow pointing left for the previous month. Alternatively, to select any other month, you can click and hold the mouse on either of the arrows and then drag it to the desired month.\n- Similarly, to display the calendar for another year, click the double-arrow pointing right for the next year, or the double-arrow pointing left for the previous year. Alternatively, to select any other year, you can click and hold the mouse on either of the double-arrows and then drag it to the desired year.\n- To change the default time, click the hour and minute boxes in the **Time** section, to increment the value by 1 unit. Alternatively, to decrement the value, hold down SHIFT and then click the respective boxes. To change the value by multiple units, point to the respective boxes and then drag to the right to increment or to the left to decrement the value.\n\n3. Select time from the **Time** drop down.\n\nThe selected date and time is displayed in the **Date** box.\n\n**Note:** By default, the **Select Date** window displays the calendar with each week starting Sunday. To change this setting to another day of the week, click the day in the calendar header.\n\n### Searching Users\n\nYou can specify a user by typing it in the various text boxes involving a users (for example, User Name, Reassign, Delegated to) or select using Select User icon, which is generally located beside the User text box.\n\n**To search a user using Select user icon, perform the following:**\n\n1. Click the Search User icon (🔍) is displayed beside the text box.\n\n **Search Users** page is displayed where you can search for the users.\n\n Refer **Figure 15** on page 37.\n2. You can select a user by performing one or more of the following operations from **Select User** page.\n\n- You can search for the users by specifying either the user name, or the first name or the last name. If you specify the group name, then it searches for the users in that group, otherwise it searches in all groups.\n- After typing the user name, first name, last name, and optionally, group, click **Go**. You can also use the \" as a wild card. Type in the first letter and then the asterisk (example, a\") and all users beginning with that letter will display. It also works for portions of names; e.g., type in \"on and all names ending in on (Jackson, Peterson, etc.) is displayed. Type Mc\"son and users such as McPherson and McWilliamson is displayed.\n\nBusiness Process Portal lists all the users satisfying your search criteria. You can navigate through this list as explained in the **Getting started** on page 21\n\n- To go directly to the list of users starting with a particular letter, click that letter in the Quick Search bar.\n\n3. Depending on the page and current operation, Business Process Portal allows you to select one or more users. Select users by clicking the options in the first column of those users, and then click **Add**.\n\nThe selected users' user names are entered in the **User Name** text box.\n\n---\n\n**Note:** Depending on the page and current operation, the **Save and Create New** button may also be available. Click this button to add the current user and continue adding more users.\n\n---\n\n**Searching Group**\n\nSearching for a group is similar to searching for a user. While searching for a group, you need to specify the group name in the **Group Name** box by typing it. Alternatively, use the Search Bar to locate the specific group by performing a procedure similar to the one explained above for searching the users.\nWorking with attachments\n\nBusiness Process Portal enables you to attach, update, and remove documents associated with entities such as tasks. For instance, you can use this feature to circulate a resume as a part of a hiring review process, or to circulate one or more functional specifications associated with a design approval process.\n\nThe ability to attach documents is not part of every task. The application must be designed to enable this feature, that is, it must employ Document dataslots for working with attachments.\n\nNote: The ability to attach documents is not part of every task. The application must be designed to enable this feature.\n\nAttachment options\n\nThe Business Process Server allows you to attach documents using the JavaScript interface.\n\nYour ability to attach, update, and remove documents depends on the type of workstep that stores the document. The possible cases are summarized in the following table:\n\n<table>\n<thead>\n<tr>\n<th>If the attachment is . . .</th>\n<th>You can . . .</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Read-only</td>\n<td>View attached documents, but you cannot attach new documents, nor can you delete or update existing attached documents. You can, however, save a copy on your computer.</td>\n</tr>\n<tr>\n<td>Read/write</td>\n<td>Attach, remove, and update documents.</td>\n</tr>\n</tbody>\n</table>\n\nWhether an attached document is in read-only or read/write mode, depends upon the settings specified while defining the document dataslot. For more information, see the Application Developer's Guide.\n\nSupported file types\n\nYou may attach any kind of file (.doc, .xls, .pdf, .gif, .html) as long as the file is located in your computer. When you open an attachment, BPM Portal lets the browser identify the associated application.\n\nNote: The default setting for document attachment size is 5 MB. In the OEBPS_HOME\\conf\\bpmportal.conf file, you can increase the default document attachment size to 300 MB.\nIntroducing the Management Module\n\nThis chapter describes the new features introduced in Business Process Server 11.5, introduces you to the Management module of Business Process Portal, and presents an overview of the Management user interface.\n\nBefore logging into the Management module, adjust your browser’s cache settings and optionally, customize the date format. For more information, see Adjusting your browser cache setting on page 40 and “Chapter 2, Customizing Properties Files” in the Customization Guide.\n\nYou can then:\n\n• Open the Management module by Logging into the Management Module on page 40.\n\n• Learn about controlling access to Management features by Reviewing User Access/Permissions on page 41.\n\nFor details, see the following topics:\n\n• Adjusting your browser cache setting\n\n• Logging into the Management Module\n\n• Using the BPM Manage API\n\n• Reviewing User Access/Permissions\nAdjusting your browser cache setting\n\nTo ensure that you are always viewing up-to-date information, you must set the cache parameter for your browser appropriately to check newer versions of stored pages every time you visit a page. For more details, refer to your browser's documentation.\n\nYou also need to install the Sun JDK version 1.5.0.10 or later, and set it as the virtual machine of your browser. For more details about downloading and installing it, refer to Sun Microsystems' site and documentation.\n\nLogging into the Management Module\n\nYou can log into the Management module through the Business Process Portal, the single sign-on portal for Business Process Server. You need to log in only once to gain access to any other Business Process Server modules for which you have been granted permissions. These modules can include Management, Home and Administration.\n\nNote: If you are using Internet Explorer 6.0 SP1, then ensure that you have the Microsoft Virtual Machine installed. To verify this, select Tools > Internet Options, and open the Advanced tab. Under the \"Microsoft VM\" heading, make sure the \"JIT compiler for virtual machine enabled (requires restart)\" checkbox is selected.\n\nAfter starting the servers, you can log into Business Process Portal. For more details, see Logging in to Business Process Portal on page 22.\n\nClick the Management tab to access the Management module. Business Process Server automatically authenticates your user name and password and displays the Instances Overview page.\n\nNote: Business Process Server’s Access Control Management feature displays an error message when you were not granted permission to use this resource.\n\nTo access features in the Management module, use appropriate module menus. This module contains the following menus:\n\n- **Overview**: Provides an overview of processes in all states, as shown in Using Management overview features on page 45.\n\n- **Reports**: Displays available reports and provides the interface to define and create reports. For more information, see Executing and creating reports on page 61.\n\n- **Instance Manager**: Allows you to efficiently manage large numbers of process instances, worksteps and tasks, and to perform tasks in batches rather than singly. For more information, see Using the Instance Manager on page 89.\n\n- **Balanced Scorecard**: Enables you to determine how your organization's business activities are helping it meet its strategic goals. For more information, see Using the Balanced Scorecard on page 101.\n- **Infopad Manager.** Enables you to update the information provided in an infopad, a table that stores such global data as application parameters or rule parameters. For more information, see Using the Infopad Manager on page 113.\n\nTo access other Business Process Server modules that are available to you, click a module tab to display a range of menus under that tab. Open a menu and select a submenu item to open the feature.\n\nOnce you log in to the Business Process Portal, no further authentication is required when you open a new module.\n\n### Using the BPM Manage API\n\nThe BPM Manage API, a public API that provides Management module users with access to data that was previously internal, facilitates the customization of Management features. Business Process Server application developers and customizers no longer need to resort to workarounds and reverse-engineering to create the customized pages that they require – the BPM Manage API now exposes the elements needed to modify the Management module to users’ specifications.\n\nThe BPM Manage API also uses HTML templates for each type of element, allowing for different levels of customization within the interface pages for each building block. The API can access the lowest-level types of data available and utilized by the Management module, which prevents one of the primary causes for the workarounds that were necessary for customization in the past. While recognizing the need for low-level support, the BPM Manage API also offers higher-level support that includes packaged data and more complex renderings.\n\nFinally, the BPM Manage API provides a set of features that enables Business Process Portal modules to share a single login command.\n\n### Accessing the BPM Manage API\n\nThe BPM Manage API is implemented as a bean, enabling the user to easily access the API from within all necessary types of applications.\n\nTo simplify code and make customization easier, the Management module provides elemental data, i.e., commonly used data that generally is formatted for use within JSPs and/or for display within servlets.\n\n### Reviewing User Access/Permissions\n\nThe Access Control Manager (ACManager) provides more comprehensive and finer-grained security for Application users. The Business Process Server administrator can determine the access level a Manager has to a specific application and what permissions the user has: for example, can the Manager access a specific process instance; or can the Management module user perform any action on a BPM SQL report. Although the results of this ACManager feature is seen in the Management module, it is defined by Business Process Server Administrators through the Administration module. If, as a Manager, you want to allow or prohibit certain user’s access to specific applications and/or grant or revoke specific permissions to a user, then contact your Business Process Server administrator. See the Business Process Portal administrator’s Guide for additional information.\nProcess-Level permissions\n\nTo better understand how ACManager access/permissions work with Management features, consider the following points involving permissions for process templates, process instances and process dataslots:\n\n- To view and/or update a process template, a Business Process Server administrator must assign you the corresponding rights. The view action enables you to see the item; the update action enables you to revise it. If you have not been assigned view and/or update permissions for a process template, then it will not appear in the Management module.\n\n- To view and/or update a specific process instance, a Business Process Server administrator must assign you the corresponding rights. You can also be assigned view/update permissions for all process instances.\n\n- To view and/or update a specific process dataslot, a Business Process Server administrator must assign you the corresponding rights. You can also be assigned view/update permissions for all process dataslots.\n\n- To view/update a process dataslot, you must be granted the associated permissions; i.e., to access a process dataslot, you must have the process instance permission and the process template permission.\n\nReport Permissions\n\nThe Business Process Server administrator must assign you the permission to perform any action on the specific report type. In Business Process Server, there are four types of reports: Query Report, MultiApps, External and Infopad Report.\n\nThe Business Process Server administrator must first grant you the permission for the application(s) from which the report is derived.\n\nTo view/execute existing Management reports:\n\n1. Once you have the required permissions, the Go button in the My Reports page is enabled and you can execute an existing report (see Running an existing report on page 67).\n\n **Note:** The report may be filtered, since any process instance or dataslot that the user does not have permissions for is not shown.\n\n2. To create a report, you must have permission for the application(s) the report is derived from and have the Create a Report permission for the application. Once these permissions are granted, the Query button in the My Reports page is enabled and you can create a report (see Creating Application (Query) reports on page 68).\n\n3. To delete a report, you need the permissions described in step 4, as well as the Remove a Report permission. With these permissions, the Delete button in the My Reports page is enabled and you can delete a report (see Removing an Existing report on page 82).\n\n4. To modify an existing report, you need the permissions described in step 4, as well as the Modify a Report permission. With these permissions, Edit Report (📝) icon is available beside the Report Name column in the My Reports page and you can modify an existing report using the Edit Report icon (see Modifying an existing report on page 81).\nTo hold ReportBuilder permissions, the Business Process Server administrator must assign you the permission to perform any action on any ReportBuilder, as well as permissions for the application(s) from which the report is derived.\n\nTo view/update BPM SQL reports, you can execute it by providing default report and default report builder as additional permissions (for more information, see About external reports on page 67).\n\nPermissions for other management features\n\nTo hold permission to view and/or update Infopads, the Business Process Server administrator must assign you the view and/or update permissions for a selected infopad.\n\n**Note:** Remember that you must verify that top-level permissions (for example, to an application) have been assigned in order for lower-level permissions (for example, updating a report) are working.\n\n**Note:** Remember that when any applications are installed in Business Process Server to which you have been granted permission as a Manager, you must log out, then log in again, to ensure that this permission is reflected in Business Process Server.\nUsing Management overview features\n\nThe Management module of the Business Process Portal is organized into a series of Web pages utilizing applets to enable you to quickly and efficiently manage Business Process Server applications. This chapter describes procedures that enable you, as a Manager, to monitor and update Business Process Server applications and process instances by performing the following functions:\n\n- Viewing the details of all the tasks, by displaying all instances for all applications, and for all worksteps of all states, or using the filtering functions to view the status of specific task for a selected application.\n\n- Checking the Status of an Instance on page 49, by displaying all instances for all applications, or using the filtering functions to view the status of specific instances for a selected application. You can also dynamically update the worksteps and work items of an instance, and print the current status of the instances.\n\n- Updating Worksteps and Work items on page 52, dynamically modifying an active or suspended workstep or work item without leaving the Management module.\n\n- Checking the Status of an Application on page 55, by selecting an application and reviewing its status. You can also view and update its global dataslots, as well as modify and send workstep instructions to other users of the selected application.\n\n**Note:** See Introducing the Management Module on page 39 for an introduction to the Management interface. See Executing and creating reports on page 61 for detailed information about using the Reports function to define and execute reports.\n\nFor details, see the following topics:\n\n- Viewing Tasks Overview page\n• Viewing Instances Overview page\n• Viewing Instance History\n• Checking the Status of an Application\n\nViewing Tasks Overview page\n\nTo view the Tasks Overview page, in the Management module, click Overview > Tasks. The Tasks page indicates the status of the tasks.\n\nTasks Overview page\n\nThe Tasks Overview page displays information about all the tasks. By default, it displays tasks of all users with any state and any priority, and the following information about each task:\n\nTable 7: Instance Overview Information\n\n<table>\n<thead>\n<tr>\n<th>Column</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Application</td>\n<td>A unique identifier for the application instance. (Only if "All" applications are selected in the filter.)</td>\n</tr>\n<tr>\n<td>Instance</td>\n<td>The name of the process instance.</td>\n</tr>\n<tr>\n<td>Instance Status</td>\n<td>The status of the filtered instance. (Only when the Process Instance Status filter is set to "All").</td>\n</tr>\n<tr>\n<td>Details</td>\n<td>Click the PSV Tabular View icon in this column to display the tabular view of the process instance. Click the PSV Flow View icon in this column to display the process instance flowchart at the point of the active task. Click the Audit History icon in this column to display the audit history of the process instance.</td>\n</tr>\n<tr>\n<td>Task</td>\n<td>The name of the task.</td>\n</tr>\n<tr>\n<td>Status</td>\n<td>The status of the task. (Only when Workstep Status filter is set to "All").</td>\n</tr>\n<tr>\n<td>Performer</td>\n<td>The name of the performer of the task.</td>\n</tr>\n<tr>\n<td>Task Priority</td>\n<td>The priority of the task.</td>\n</tr>\n<tr>\n<td>Assigned Date</td>\n<td>The date when this task is assigned to the performer.</td>\n</tr>\n<tr>\n<td>Due Date / End Date</td>\n<td>The date when the task is due or is to be completed.</td>\n</tr>\n</tbody>\n</table>\n\nThese columns are sortable; that means, you can sort the contents of this page based on this column header. For more information, see Sorting a column on page 27. This helps to quickly locate tasks(s) based on the application specific dataslot values.\nViewing Instances Overview page\n\nTo view the **Instances Overview** page, in the Management module, click **Overview > Instances**. This page indicates the status of the application instances.\n\nIn the Instances Overview page, you can search for a specific instance.\n\nTo search for a specific instance:\n\n1. Select search based on **Instance Id**. The Instance Id text box is available.\n2. Provide the instance id and then click **Search**.\n \n The instance with that particular instance id is displayed. If it is a not valid instance id, then No records found message is displayed.\n\nInstances Overview page\n\nThe **Instances Overview** page displays information about the application instances you are currently using. By default, it displays all instances and the following information about each instance:\n### Table 8: Instance Overview Information\n\n<table>\n<thead>\n<tr>\n<th>Column</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Attributes</td>\n<td>Select this option to search based on any attribute.</td>\n</tr>\n<tr>\n<td>Instance Id</td>\n<td>Select this option to search based on a specific attribute.</td>\n</tr>\n<tr>\n<td>Application</td>\n<td>A unique identifier for the application instance.</td>\n</tr>\n<tr>\n<td>Instance</td>\n<td>The name of the process instance.</td>\n</tr>\n<tr>\n<td>Status</td>\n<td>The status of the filtered instance.</td>\n</tr>\n<tr>\n<td>Creator</td>\n<td>The name of the user who created the instance.</td>\n</tr>\n<tr>\n<td>Details</td>\n<td>Click the PSV Tabular View icon in this column to display the tabular view of</td>\n</tr>\n<tr>\n<td></td>\n<td>the process instance. Click the PSV Flow View icon in this column to display</td>\n</tr>\n<tr>\n<td></td>\n<td>the process instance flowchart at the point of the active task. (See Step</td>\n</tr>\n<tr>\n<td></td>\n<td>Table 9 on page 51 for color coding) Click the Audit History icon in this</td>\n</tr>\n<tr>\n<td></td>\n<td>column to display the audit history of the process instance.</td>\n</tr>\n<tr>\n<td>Priority</td>\n<td>Priority level as determined by the user initiating the process instance.</td>\n</tr>\n<tr>\n<td>Estimated</td>\n<td>Estimated duration to complete the process instance as determined by the</td>\n</tr>\n<tr>\n<td>Duration</td>\n<td>application developer.</td>\n</tr>\n<tr>\n<td>Start Date</td>\n<td>The date the process instance was initiated.</td>\n</tr>\n<tr>\n<td>Due Date</td>\n<td>The date by when the process instance should be completed as determined by</td>\n</tr>\n<tr>\n<td></td>\n<td>the application developer.</td>\n</tr>\n<tr>\n<td>End Date</td>\n<td>The date on which the process instance was completed.</td>\n</tr>\n</tbody>\n</table>\n\nIn addition to the default columns, you can add dataslots as columns using the **New Dataslot** dialog box in the Progress Developer Studio for OpenEdge. For more information, see *OpenEdge Getting Started: Developing BPM Applications with Developer Studio*. These dataslot columns are sortable; that means, you can sort the contents of this page based on this column header. For more information, see *Sorting a column* on page 27. This helps to quickly locate instance(s) based on the application specific dataslot values.\n\n**Note:** Specify the date format for the reports using the `DateFormat` parameter in `bpmportal.properties`. See \"Chapter 2, Customizing Properties Files\" in the *Customization Guide* for more information about the date format syntax. Business Process Server displays a warning message when you specify an invalid format for a `Date` field.\n\nTo manage the contents of the list, you can filter and/or sort them. To navigate through the pages, you can use the paging controls. For more details about these operations, see *Exploring Business Process Portal* on page 24.\n\nThe **Instances Overview** page enables you to:\n\n- Search based on Attributes or Instance Id.\n• Search for a specific instance by providing the Instance Id.\n\n• Use the attributes Filter bar to search through all applications, or a selected application, for specific process instances.\n\n• Check the status of the specified process instances.\n\n• Open the Tabular View to see the properties of each workstep displayed in a tabular format that presents data in a unified view.\n\n• Open the Flow View to see the process flow (i.e., the flow of work from one workstep to the next). From the Flow View, you can also see the instance’s information flow (i.e., the flow of data from one workstep to the next), as shown in the Dataslots View.\n\n• Open the Audit History to view the audit history information of the process instance, as described in Viewing Instance History on page 55.\n\nNote: This page is also the Management module’s default page, and the user can return to this page at any time by clicking the Management tab in the Business Process Portal.\n\nChecking the Status of an Instance\n\nTo check the status of an instance, complete the following steps:\n\n1. In the Management module, click Overview > Instances, to view the Instances Overview page.\n\n2. Use the search features in the Filter bar to specify the process instances you want to monitor.\n a) Select a Business Process Server application from the Applications drop-down list in the upper left of the Filter bar. Data on all instances for the selected application (or for all applications, when you choose All) are displayed in the workspace.\n b) Select an option from the Status drop-down list. Options include: All, Active, Completed, Removed or Suspended. Active indicates the instance is active and can be run. Suspended indicates the instance is temporarily stopped until the Resume option is selected.\n c) Select an option from the Duration drop-down list. Options include: Hours, Weeks, Days, Business Days. Use this search criteria only for instances with a Completed status.\n d) Specify a Creator, if applicable. Click the Edit Creator icon ( ) to open the User List, from which you can select a valid Application user.\n e) Select an option from the Priority drop-down list. Options include: All, Critical, High, Medium and Low.\n f) Select an option from the Date drop-down list. Options include: Today | Yesterday, This Week | Last Week, This Month | Last Month, et al. To define a more specific time range, click the Select Date icon ( ) and choose a start date and end date from the pop-up calendars.\n\n Note: Instances can be filtered based on the Instance Start Date by specifying the start date from the Start Date drop-down list.\n\n3. After you have finished entering filtering criteria, click Search to locate the specified instance(s). Business Process Server displays all the instances satisfying your filter criteria in the workspace. See Table 8 on page 48.\nNote: Specify the date format for the reports using the DateFormat parameter in `bpmportal.properties`. See \"Chapter 2, Customizing Properties Files\" in the Customization Guide for more information about the date format syntax. Business Process Server displays a warning message when you specify an invalid format for a Date field.\n\n4. Click the PSV Tabular View icon in the Details column to view the properties of each workstep displayed in a tabular format that presents data in a unified view.\n\nThe Tabular View displays the Start workstep as the first workstep at the top of the list. It is followed by the remaining worksteps in the order of their completion and the End workstep is displayed as the last workstep. The same color coding described in Step Table 9 on page 51 is also used in the Tabular View.\n\nRefer Figure 16 on page 50.\n\n**Figure 16: Tabular View**\n\nWhen you are in the Tabular View, you can:\n\n- Update an Active workstep by modifying its Priority or by changing its Status; for example, suspend, complete and update.\n- Update a work item by changing the Performer or selecting an Action. For Reassign, Complete, Make Available and Remove.\n- Send an e-mail to the performer(s) by clicking the Performer link. Business Process Server launches your default mail client and enters the e-mail addresses of the performer(s). If there are multiple performers comprising any combination of, list of users and list of groups, then Business Process Server enters individual e-mail addresses of those users and group members. However, if a group contains users and another group, then Business Process Server enters e-mail addresses of only the users but does not enter e-mail addresses of the nested group's members.\n- Expand all Worksteps to show their work items in a printer-friendly version of Tabular View.\n- Printing the Tabular view.\n\n5. Click the PSV Flow View icon in the Details column to open the Flow View, where you can view the instance in a flowchart.\nFigure 17: Flow View\n\nThe worksteps color coding is explained in Step Table 9 on page 51.\n\nTable 9: Workstep Color Coding\n\n<table>\n<thead>\n<tr>\n<th>Workstep Color...</th>\n<th>Indicates...</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Orange</td>\n<td>Activated workstep</td>\n</tr>\n<tr>\n<td>Green</td>\n<td>Completed workstep</td>\n</tr>\n<tr>\n<td>Gray</td>\n<td>Inactive workstep</td>\n</tr>\n<tr>\n<td>Blue</td>\n<td>Skipped workstep</td>\n</tr>\n<tr>\n<td>Red</td>\n<td>Suspended workstep</td>\n</tr>\n<tr>\n<td>Dark Green</td>\n<td>Monitoring workstep in wait state.</td>\n</tr>\n</tbody>\n</table>\n\nThe Event Playback in the PSV link bar helps you to view the events in the order in which they have occurred. Refer \"Using Event Playback\" section in Business Process Portal User’s Guide for more information.\n\n6. To access dataslot information for the process instance from the Tabular or Flow View, click View Dataslots to open the View Dataslots page. This page appears if you are granted Dataslot permissions.\nIf you have only View permission for the Dataslot resource, then the fields in the View Dataslots page are read-only. If you have View and Update permissions for the Dataslot resource, then the fields are editable, as shown above.\n\nTo change the dataslot information for the process instance:\n\na) Modify the priority of the instance by selecting an option in the Priority drop-down list.\nb) Modify the status of the instance by selecting from the options in the Status drop-down list.\n\nc) Modify the remaining dataslots as needed, and click Save at the bottom of the form. Business Process Server updates the dataslots after your confirmation. To reset the form and remove the information you just entered, click Reset. To cancel the action and exit the current page, click Cancel.\n\n7. To access the history of all the transactions of the process instance from the Tabular or Flow View, click Audit History to open the Audit History page. For more information about audit history, refer to Viewing Instance History on page 55.\n\n**Updating Worksteps and Work items**\n\nYou can dynamically update worksteps and work items in the Management module by performing the following procedure:\n\n1. From the Flow View page, click any completed (green), active (orange) or suspended (red) workstep from the flowchart to open the Workstep Details window.\n2. The Workstep Details window for a completed workstep displays read-only data that cannot be modified.\nActive or suspended worksteps display a dialog window with editable fields, where you can update certain workstep and work item properties.\n\nThe following figure presents the **Workstep Details** window for an active workstep.\n\n3. To send an e-mail to the performer(s), click the Performer link. Business Process Server launches your default mail client and enters the e-mail addresses of the performer(s). If there are multiple performers comprising any combination of, list of users and list of groups, then Business Process Server enters individual e-mail addresses of those users and group members. However, if a group contains users and another group, then Business Process Server enters e-mail addresses of only the users but does not enter e-mail addresses of the nested group’s members.\n\n4. To dynamically modify an active or suspended workstep or a work item during run-time:\n a) In the Workstep Details section, select an option from the Priority drop-down list to update the workstep’s priority.\n b) In the Work item(s) section, update information about the Performer by entering data in the Performer box or by clicking  to open the **User List** page, where you can select a valid user from the list of Application users.\n c) In the Work item(s) section, update Action information by selecting an option from the drop-down list in the Action column.\n d) If you want to suspend the workstep, then click **Suspend Workstep**. The **SuspendWorkstep** option changes the workstep color to red, and temporarily stops the process at the suspended workstep until the issue causing the suspension is resolved or you resume workstep execution.\ne) If you want to complete the workstep, then click **Complete Workstep**. The **CompleteWorkstep** option changes the workstep color to green. Business Process Server takes a while to mark the workstep as completed and change its color. Therefore, you may must refresh the page more than once to reflect the color change.\n\nf) If the Completed workstep has been designated as a Rollback Point (i.e., it is the workstep from which the workflow is restarted when a process fails during execution), then a **Rollback** button is displayed in the **Workstep Details** window. Select **Rollback** to \"roll back\" the process to the rollback point.\n\ng) The Dataslots section displays a list of dataslots used for the selected workstep. If you have permissions to update the dataslots, then you can update individual dataslot values.\n\nh) The **Audit History** section displays the audit history details of the selected workstep.\n\n5. Click **Save** to save any changes you made in the **Workstep Details** page. Business Process Server automatically reloads the Flow View.\n\nClick **Reset** to clear any data you entered and return to the original settings. Click **Cancel** to delete any updates, and return to the **Flow View** page.\n\n---\n\n**Note:** Completed worksteps and work items cannot be modified. Removed instances also cannot be modified.\n\n**Printing the Flow View in the Process Status Viewer**\n\n**To print the Flow View:**\n\n1. Use the Zoom in and Zoom out icons to specify the size for the Flow View. Business Process Portal prints the Flow View using the zoom level you have selected.\n\n **Note:** You can use the zoom feature to print the entire Flow View in a single page. This can be used for the Flow View and Heatmap.\n\n2. Click the **Print** icon ( 📐) to open the **Print** dialog box.\n\n Refer Figure 17 on page 51.\n\n3. Specify the appropriate settings, and click **Print** to directly print the current Flow View. The Flow View is printed with a page title and page number.\n\n **Note:** You can also print the flow view as a PDF by selecting Adobe PDF in your settings.\n**Viewing Instance History**\n\nBusiness Process Server maintains a complete transactional audit of a process instance, in the form of events in the database. These events capture changes in the process instance status, as well as dataslots. You can view these instance history details from the Audit History page. To view the audit instance history, from the Instances Overview page, click the Audit History icon for the process instance, whose information is to be viewed. Alternatively, click the Audit History link from the Tabular View or Flow View of a process instance. The Audit History page is displayed, comprising of the Header section and the Details section. This page and the procedures you can follow using this page are identical to the Audit History page you can access in the Home module. For more information, see “Chapter 7, Working with My Instances” in the Business Process Portal User’s Guide. In the Audit History page, the values for the Completed on, Total duration and Elapsed time fields can be seen only by the user with managerial privileges when all tasks of that process instance are completed.\n\n**Checking the Status of an Application**\n\nTo view the Application Overview page, in the Management module, click Overview > Applications. The Application Overview page enables you to:\n\n- Check the status of one or more selected applications.\n- See the heatmap view of an application, which gives overview of active, suspended and completed instances of the application.\n- See the tabular view which enables you to view and update workstep-level instructions for worksteps of a selected application.\n- See the information flow at the application level, by opening the Global Dataslots view.\n- Add or modify application-level information such as, instructions, and URL links.\n\n**To check the status of an application, complete the following steps:**\n\n1. In the Management module, click Overview > Applications. The Application Overview page is displayed.\n\n2. Select a Business Process Server application and/or select a status from the Applications and Status drop-down list respectively, and click Go. The Application Overview page is displayed. This page displays information about the applications satisfying your filtering criteria. By default, it displays all applications and the following information about each one of them:\n\n<table>\n<thead>\n<tr>\n<th>Column</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Application</td>\n<td>Displays the application name.</td>\n</tr>\n<tr>\n<td>Status</td>\n<td>Displays the application status.</td>\n</tr>\n</tbody>\n</table>\nClick the Tabular icon in this column to view and update workstep instructions.\n\nClick the Flow icon in this column to view the heatmap view of the application.\n\nTo navigate through the pages, you can use the paging controls. For more details about this operation, see Exploring Business Process Portal on page 24.\n\n3. Click the Tabular icon in the Tabular column to view each workstep for a selected application displayed in a tabular format. Here, you can enter new, or modify existing, instructions for each workstep.\n\n4. Click the Flow icon in the Flow column to view a workflow chart of the selected application in the workspace.\n\n Click a workstep to open the Tasks Overview window.\n\n For more details, refer to Viewing Tasks Overview page on page 46.\n\n5. To change from the Tabular view, click the Flow View link to view the Flow View. Similarly, to change from the Flow view, click the Tabular View link to view each workstep for a selected application displayed in a tabular format. Here, you can enter new, or modify existing, instructions for each workstep.\n\n6. Click Save to save any changes you made in the Workstep Instructions window or in the Tabular View page. Click Reset to clear any data you entered and return to the original settings. Click Cancel to delete any updates, and return to the previous page.\n\nUsing the Heatmap\n\nWhen you click the Flow icon for a process in the Application Overview page, a color-coded Flow View or Heatmap is displayed.\n\nA heatmap helps a Manager to:\n\n• Get an overview of the status of the currently active instances. Using this as a tool a business manager can identify potential bottlenecks in the process.\n\n• Identify worksteps that have been suspended, for a variety of reasons and take necessary actions to resume the suspended processes.\n\n• Analyze the history of the completed instances to identify potential trends and opportunities for optimization.\n\nIn the Flow View, you can use the Process Instance Status drop-down list to filter the instances and Workstep Status drop-down list to filter the worksteps in the heatmap based on their status. You can select Completed from the PI Status, select Activated, Suspended or Completed or Monitoring wait from the Workstep Status, and then click Go, or select Activated from the PI Status, select Activated, Suspended or Completed from the Workstep Status, and then click Go. The heatmap graphically shows the status of all worksteps for the specified status of process instances. For example, if you select Activated from the PI Status drop-down list, Suspended from the Workstep Status drop-down list and click Go, then the heatmap displays all suspended worksteps of all the active process instances. When you change the Process Instance Status option, it automatically updates the options in the Workstep Status drop-down list. However, to refresh the heatmap, you need to select the PI Status option, select Workstep Status option, and then click Go.\nEach workstep is color-coded as described in the following table.\n\nTable 11: Heatmap Color Coding\n\n<table>\n<thead>\n<tr>\n<th>Color Range</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Red to Green</td>\n<td>For values between the maximum and the median.</td>\n</tr>\n<tr>\n<td>Green to Blue</td>\n<td>For values between the median and the minimum.</td>\n</tr>\n</tbody>\n</table>\n\nThe legend in a heatmap does not display all the bin colors. It displays only the colors that are used in that heatmap.\n\nThe number in the parenthesis after the activity label indicates the total number of workstep instances of the specified status.\n\nA bottleneck can be identified by a red workstep immediately followed by one or more green worksteps.\n\nRefer Figure 21 on page 57.\n\nFigure 21: Heatmap of a Bottleneck\n\nHeatmap Algorithm\n\nHeatmap works based on the values of total instances of the application for the given process instance status and total instances that executed each workstep for the given activity status.\n\nThe heatmap algorithm uses nine different bins to uniformly distribute the process instance count of the selected application into them. Each bin in the heatmap has an associated fill color as shown in the following figure. Bin number starts from zero.\n\nThe following figure displays the bin number or bin index in each bin.\n\nFigure 22: Bin Colors in Heatmap\n\n---\n\n2 Median is calculated by adding all the values for each activity and dividing this sum by the total number of activities.\nCalculating Range\n\nThere are two steps involved in calculating the range (lower bound and upper bound) of values of each bin.\n\nPerform the following to calculate range:\n\n1. Calculate the binSize by dividing the total number of process instances with total number of bins. The total number of bins are always 9.\n \n Refer Heatmap Algorithm on page 57.\n \n That is binSize = total process instance count / total number of bins\n\n2. Calculate the Range (Lower bound and Upper bound) of values of each bin as\n a) The Lower bound value is - binIndex times binSize, mathematically rounded.\n b) The Upper bound value is - binIndex plus one times binSize, mathematically rounded.\n\n For example, if there are 18 instances of an application, then the binSize of that heatmap is\n \n binSize = 18/9 = 2\n\n The range of values stored by the 1st bin is, that is bin index of 0.\n \n • Lower bound = (0 * 2) = 0\n • Upper bound = (0 + 1) * 2 = 2\n\n The range of the 1\\text{st} bin (bin with index of zero) would be greater than zero and less than 2. The range of the 2\\text{nd} bin (bin with index of one) would be greater than 2 and less than 4.\n\nImportant: Note that the bin value zero is considered as a separate bin and Business Process Portal displays these process instances in gray in heatmap.\n\nInstance Distribution\n\nWhile rendering the heatmap, for each activity, Business Process Portal checks how many instances of that application have executed that activity.\n\nFor example, if there is a heatmap where the process instance status is completed, and workstep status is completed, then for each activity Business Process Portal calculates how many instances of that application completed that workstep. That value is used to find the fill color of that activity from the heatmap algorithm. The heatmap algorithm then finds out the bin range in which that value falls. If the value falls in one of the bin range values, then that bin’s associated fill color is used for those activities.\n\nFor example, if only five instances completed a particular workstep, say workstep1, then you can see which bin holds the value of five. In the above example, the 3rd bin, that is, bin[2] holds the value of five. Therefore, it uses the bin[2]’s fill color while drawing the activity.\n\nThe same logic is used where the Process Instance status is active, and workstep status is Activated, Completed or Suspended.\n\nIf a workstep is not in the state specified in the user’s filtering criteria in any of the instances, then such a workstep is displayed in gray.\n\nUsing this heatmap diagram you can identify which activities are more frequently accessed, less frequently accessed, and those that are never accessed.\nUsing the Histogram\n\nBusiness Process Portal renders a Histogram, which is a two dimensional chart with X and Y axis values, using the values calculated for the heatmap. For more information, refer to the Heatmap Algorithm on page 57. In this histogram, the X-axis plots the Activity Execution count, and the Y-axis plots the Instance Range values, that is, bin ranges.\n\nTo access the Histogram, click the graph toolbar button in the Heatmap.\n\nThe Histogram window is displayed as shown in Figure 23 on page 59.\n\nFigure 23: Histogram\n\nModifying Global Dataslots\n\nGlobal dataslots are application-level dataslots that occur in each process instance of the application. In previous releases, dataslot values were limited to individual process instances.\n\nTo view and/or dynamically update dataslot information globally (i.e., at the application level), from the Management module:\n\n1. In the Management module, from the Application Overview page, click the application name to display Global Dataslots page; or click the Tabular or Flow icon and then click Global Dataslots to display the Global Dataslots page. The Global Dataslots page displays all the global dataslots in that application.\n2. Modify the information in the activated boxes as required.\n3. Click Save to save your changes. Business Process Server reloads the page and automatically updates the values across all process instances.\n\nTo reset the form and remove the information you just entered, click Reset. To cancel the action and exit the current page, click Cancel.\nUpdating Application Information\n\nThe Application Information feature in the Management module enables you to provide information about an application to the application users.\n\nYou can provide the information as a plain text or as a link. The information you specify here is displayed in the Information column on the Applications page of the Home module.\n\nTo use the Application Information feature:\n\n1. In the Management module, click Overview > Applications. The Application Overview page is displayed.\n2. Click the Tabular icon in the Tabular column or the Flow icon in the Flow column. The Tabular or Flow view is displayed.\n3. Click the Application Information link. The Application Information page is displayed, as shown below. By default, three rows are displayed.\n4. Specify comments or other details in the Information box.\n Optionally, specify a URL in the corresponding URL box. If you specify a URL, then the text you specify in the Information box is displayed as a hyper link which leads to this URL.\n5. To add rows, click Add 3 Rows. A set of three rows are automatically added.\n To delete one or more rows, select the checkbox for each row you want to remove and click Delete Rows.\n6. Click Save to save the changes.\n To reset the form and remove the information you just entered, click Reset. To cancel the action and exit the current page, click Cancel.\nExecuting and creating reports\n\nThis chapter describes how Managers can use either JasperReports or the Business Process Server Report Builder to create new reports or use existing reports to further manage and review Business Process Server applications.\n\nFor details, see the following topics:\n\n- Creating and deploying reports using JasperReport\n- Setting up Jasper Assistant plugin in Progress Developer Studio for OpenEdge\n- Creating and executing reports in Business Process Portal\n- Running an existing report\n- Creating Application (Query) reports\n- Creating Multiapplication reports\n- Creating External reports\n- Modifying an existing report\n- Removing an Existing report\n- Task Filtering for reports\n- Defining Infopad Reports\nCreating and deploying reports using JasperReport\n\nYou can use the extensive reporting capabilities of JasperReports — an open source Java reporting tool — to create and execute reports that meet your specific requirements. You may use any JasperReports Designer to create your reports. However, ensure that it is saved as a \"jrxml\" file. You can deploy your JasperReports as a common report or specific application report.\n\nImportant:\nWhile creating reports using iReport tool, it is recommended to set the Language option to Java from the Properties dialog. The default option for Language is Groovy in iReport, Business Process Server does not support Groovy runtime.\n\nDeploying as a Common Report\nTo deploy your JasperReports as a Common Report in Business Process Server, copy your report file (jrxml) to %WEBAPP_DIR%/ebmsapps/common/reports directory, where %WEBAPP_DIR% is the value of the oebps.webappdir parameter from the OEBPS_HOME/conf/oebps.conf file.\n\nDeploying as an Application Report\nTo deploy your JasperReports as an application specific report in Business Process Server, in %WEBAPP_DIR%/ebmsapps/<application_name> directory, create reports folder and copy your report file (jrxml) to reports directory. Here %WEBAPP_DIR% is the value of the oebps.webappdir parameter from the OEBPS_HOME/conf/oebps.conf file.\n\nUsing a Database other than Business Process Server Connection Pool\nIf you want to use a database other than Business Process Server, then you must create a file in the same directory where your report is stored, with the name <report_name>.properties.datasource. This file should contain the JDBC URL, driver class, user name and password.\n\nSample code\nA sample of this file is shown below:\n\n```java\n# This file has been provided to set sample jasper jdbc datasource for sample jasper report\n# jasper.reports.datasource.url: JDBC URL\n# jasper.reports.datasource.driver: Driver Class\n# jasper.reports.datasource.user: User\n# jasper.reports.datasource.password: Password\n\njasper.reports.datasource.url=<your_database_url>\njasper.reports.datasource.driver=<your_database_driver>\njasper.reports.datasource.user=<your_database_user>\njasper.reports.datasource.password=<your_database_password>\n```\nIn order to avoid compilation error(s), make sure that the driver classes already exist in your portalServer class path.\n\n**Adding JAR files to Jasper compiler class path**\n\nTo add your custom classes to Jasper compiler class path, follow these steps:\n\n1. Open the `bpmportal.conf` file from the `%OEBPS_HOME%\\server\\conf` directory.\n2. Add your JAR file separated with \"|\" token to the `bpmportal.jasper.compiler.classpath` attribute, and save the file.\n\nA sample of this file is shown below:\n\n```xml\n#<param name=\"bpmportal.jasper.compiler.classpath\">\n# <alias>Jasper Compiler Classpath</alias>\n# <visible>true</visible>\n# <description>This classpath is used to set jasper compiler for reports.</description>\n# <legalvalues>Should contain bpmportal.jar, jasperreports.jar, servlet.jar, commons-digester.jar\n# and %APPSERVER%/sbm.war/WEB-INF/classes in classpath format.</legalvalues>\n# <group>CONFINFO</group>\n#</param>\nbpmportal.jasper.compiler.classpath=@OEBPS_HOME@/lib/bpmportal.jar|\n@WEBAPP_DIR@/WEB-INF/lib/jasperreports.jar|\n@WEBAPP_DIR@/WEB-INF/lib/commons-digester.jar|<your_class_path>\n```\n\n**Setting up Jasper Assistant plugin in Progress Developer Studio for OpenEdge**\n\nYou can use Jasper Assistant plugin with OpenEdge to create your Jasper reports. While installing Progress Developer Studio for OpenEdge, select the Progress Developer Studio for OpenEdge with Eclipse option. You may select other options as per your requirements.\n\nDownload the Jasper Assistant Plugin for JasperReports 1.3.0 from the Jasper Assistant website http://www.jasperassistant.com, extract its zip file in a directory, and copy only the feature and plugin directories with their contents to the Progress Developer Studio for OpenEdge installation directory at `$DLC\\Developer Studio\\eclipse`. Similarly, also download GEF-runtime-3.0.1.zip from http://www.jasperassistant.com. Note that the GEF-runtime-3.0.1 files starts from default Eclipse directory. Therefore, it is recommended that you extract it into temporary directory and then copy the features and plugins directories with their contents into your `$DLC\\Developer Studio\\eclipse` directory.\n\nTo create a JasperReport using Jasper Assistant plugin in Progress Developer Studio for OpenEdge:\n\n1. Start the Progress Developer Studio for OpenEdge. From the main menu, select **Window > Preferences**.\n\n The **Preferences** dialog window appears.\n2. Create a Jasper Report using Jasper Assistant. For more information about creating a Jasper Report, refer to the Jasper Assistant documentation.\n\n3. After creating a Jasper Report, from the File menu, click Save All and close Progress Developer Studio for OpenEdge. An application with the name you specified is created in the %STUDIO_HOME%/Workspace directory.\n\n4. Copy this to %OEBPS_HOME%/ebmsapps directory. Create a folder with name reports in the %OEBPS_HOME%/ebmsapps/<application_name> directory. Ensure that the <application_name>.jrxml file is copied from the <application_name>/processtemplates directory to <application_name>/reports directory. This defines it as a application report. You can also copy this file to %APP_SERVER_HOME%/sbm.war/ebmsapss/common/reports directory to define this report as a common report.\n\n5. Publish this application from the OpenEdge.\n\n6. Install the application. The newly created Jasper Reports are listed in the Report List page of the Management module.\n\nNote: If you want to specify datasource other than Business Process Server database, then you must create the report.properties.datasource file, and enter the details of the new datasource in it. For more information, see Using a Database other than Business Process Server Connection Pool on page 62.\nManaging Reports Created Using JasperAssistant\n\nTo access the report you created using JasperAssistant through the Business Process Portal:\n\n1. In the Management module, click Reports > My Reports, to view the Report List page.\n2. From the Report drop-down list, select the application where you saved the report you created using JasperAssistant or select All Reports. Click Go, and the reports are displayed in the workspace.\n3. For JasperReports, a drop-down list is displayed in the View Format column that provides options for the report’s presentation. By default, it is set to HTML. Other options include: PDF, RTF, CSV, XLS and XML.\n The XML and XLS options display a link. You can right-click on that link and save the report in your machine to view it locally.\n4. JasperReports may also include Broadcast and Schedule options. Click the Broadcast icon to open the Broadcast Report page, where you can enter data to automatically email the report to specific addresses.\n You can enter the subject, add comments and select the format of attachments. Options include: HTML, PDF, RTF, CSV, XLS and XML.\n5. To run and distribute the report on a specific date and on a predetermined frequency:\n a) Select the Yes option in the Schedule section.\n b) Enter a date in the Date box or click the Select Date icon to display a calendar that facilitates the date entry. Select an option from the Frequency drop-down list.\n c) Click Save to execute the Broadcast and Schedule operations. Business Process Server saves these settings after your confirmation.\n6. To view the report, select this JasperReport in the Report List page, select a format from the View Format drop-down list, and click View.\n\nTo modify the report, return to Progress Developer Studio for OpenEdge. Use Business Process Server to only view and/or run the reports developed in Progress Developer Studio for OpenEdge with JasperAssistant plugin.\n\nCreating and executing reports in Business Process Portal\n\nUsing the Management module, you can define and execute single application reports, multi-application reports, and external reports. In the Management module, click Reports > My Reports, to view the Report List page. This page presents the three possible scenarios explained in the following table:\nTable 12: Reports display scenarios\n\n<table>\n<thead>\n<tr>\n<th>If there are . . .</th>\n<th>You will see . . .</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>No Business Process Server applications specified to be monitored by the user.</td>\n<td>No Records Found.</td>\n</tr>\n<tr>\n<td>No existing or predefined reports available.</td>\n<td>No Records Found.</td>\n</tr>\n<tr>\n<td>Existing, predefined reports for selected Business Process Server applications, multiple Business Process Server applications, or externally defined reports.</td>\n<td>The following information:</td>\n</tr>\n<tr>\n<td></td>\n<td>• The type of report</td>\n</tr>\n<tr>\n<td></td>\n<td>• The application name for which the reports are defined</td>\n</tr>\n<tr>\n<td></td>\n<td>• The name of each report</td>\n</tr>\n<tr>\n<td></td>\n<td>• The description of each report</td>\n</tr>\n<tr>\n<td></td>\n<td>• The format of the report</td>\n</tr>\n<tr>\n<td></td>\n<td>• The number of reports, displayed as Total: x</td>\n</tr>\n</tbody>\n</table>\n\nNote: No support of localization for database columns.\n\nThe Report List page enables you to define your own business reports. Use this page to:\n\n- Execute existing reports.\n- Create reports for a single application, multiple applications, and external report servers.\n- Test a new query.\n- Modify existing reports.\n- Define parameters for reports.\n- Remove existing reports.\n\nYou may have defined several reports in the selected application. Select one of the listed reports and click View to execute the report and view each report instance, listed under the report’s defined attributes (for more information, see Running an existing report on page 67). To create a report, use the Add Report button at the top of the page.\n\nAbout Multiapplication reports\n\nCreating multi-application reports enables you to monitor and manage multiple applications at the same time. For example, managers can create a report that lists all application instances for a particular user independent of the application. You can also define reports that perform filtering on various task attributes.\n\nFor more information about creating or modifying Multiapplication reports, see Creating Multiapplication reports on page 72. Select Multiapplications from the Report drop-down list on the Report List page to list the available MultiApp reports.\nAbout external reports\n\nCreating external reports enables you to access and execute reports using external report servers. You can send parameters and values to report servers which generate reports accessible through the Management module of the Business Process Portal. The following table describes the types of external reports.\n\nTable 13: External report types\n\n<table>\n<thead>\n<tr>\n<th>Report type</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Crystal Reports</td>\n<td>If the Crystal Reports tool is installed on your network, then this option accesses all available reports generated through this application.</td>\n</tr>\n<tr>\n<td>HTML</td>\n<td>Similar installation as Crystal Reports except the default URL button is disabled and is not used to create HTML reports. Reports are generated using external reporting servers or ASP in HTML format.</td>\n</tr>\n<tr>\n<td>BPM SQL</td>\n<td>Reports generated using BPM SQL. This capability is integrated with Business Process Server, enabling you to place SQL statements in a file (you must use the *.bizsql extension for the database) for execution by the Management module. Typically, this file is stored in the <WebAppDir>\\BizManage\\reports folder under the path that your application server is using. The <WebAppDir> path is the value of the oebps.webappdir parameter from the OEBPS_HOME\\conf\\oebps.conf file. For example, for JBoss application server, the path is</td>\n</tr>\n<tr>\n<td></td>\n<td>- For Windows: OEBPS_HOME\\jboss\\webapps\\deploy\\sbm.war\\BizManage\\reports</td>\n</tr>\n<tr>\n<td></td>\n<td>- For UNIX: OEBPS_HOME\\jboss\\webapps\\deploy\\sbm.war\\BizManage\\reports</td>\n</tr>\n</tbody>\n</table>\n\nOnce executed, Business Process Server formats the results and presents the output using standard HTML. Users can view only those BPM SQL reports for which they have been given permissions. These permissions are controlled using the Permission Create page in the Administration module. For more information on BPM SQL security, see the Business Process Portal Administrator’s Guide.\n\nRunning an existing report\n\nTo execute an existing report, complete the following steps:\n\n1. In the Management module, click Reports > My Reports, to view the Report List page.\n2. Select the type of report that corresponds to the existing report you want to execute from the Reports drop-down list at the top of the page, and click Go.\nYou can choose between Multiapplications (draws data from more than one application), All Reports (lists all available applications), External Reports (integrates with an external report server), or select a specific application (provides a Query report or an Infopad report for a single application).\n\n3. Select a report from the list of reports, select the format in which the report is to be presented from the View Format drop-down list, and click View to run the report and display it in the View Report page.\n\nFor all reports except Infopad Reports, the View Format drop-down list contains HTML, PDF, and RTF option, whereas, for Jasper Reports, in addition to these, it also contains CSV, XLS, and XML options. Business Process Portal does not display the View Format drop-down list for an Infopad Report.\n\nThe report name, is displayed above the table, and each process instance within the report is listed as a row in the table. Columns represent attributes you selected when creating the report (see Creating Application (Query) reports on page 68).\n\nYou may use various options, controls, and links available on the View Report page to see more details.\n\nCreating Application (Query) reports\n\nThis section describes how to use Business Process Server's Report Builder to define new queries and create reports of application and task instances from a single application. After first defining a new query, the user can then save the defined query as a new report.\n\nNote: See Creating External reports on page 75 for more information on defining a query and creating External Reports.\n\nTo define a new query:\n\n1. From the Report List page, select the report type from the drop-down list at the top of the page (refer to Creating and executing reports in Business Process Portal on page 65).\n Selecting Query Report enables you to create a report from one of the installed applications.\n\n2. Click Add Report, and the Add Application (Query) window for the report type you chose in the preceding step opens.\n\n Figure 25: Add Report Window\n3. Select the application for which you want to create a report from the Application drop-down list.\n\n4. Click **Query** to display the **Query** dialog window (see Creating External reports on page 75). Business Process Server selects the Application Report type and the Application Attributes tab by default. The list of attributes shown in this Application Attributes tab differs from the attributes associated with a Multiapplication Report.\n\n5. Select one of the following report types:\n - **Application Report.** Business Process Server retrieves only the application attributes, which are displayed in the panel on the left of the **Query** dialog window.\n - **Task Report.** Business Process Server retrieves application attributes and all task attributes (work items) related to the application that have been assigned to the user.\n\n Figure 26: Application Attributes Tab in Query Dialog Window\n\n6. Select the application and/or task attributes you want to include in the query definition (which can later be saved as a new report).\n \n The Name attribute is mandatory and is always selected.\n\n7. Click the **Filters** tab.\n\n The **Filters** tab enables you to customize the information presented in your reports. Select attributes for the filter from those listed in the Select Attributes panel. The contents of the **Define Filter** panel changes to match the particular attribute selected in the Select Attributes panel.\n\n8. To define a filter, type the reference value into the Name text box in the central section of the **Query** dialog window, or click the ellipsis button (…) next to the Name text box to have Report Builder display the list of all available values that have been defined.\n9. After selecting and defining a filter to apply to the new query definition, click **Add**.\n\n Business Process Server adds the filter to the list in the Current Filters panel. Use the **Delete** button to remove selected filters from this list.\n\n10. Add additional filters, when required.\n\n11. Click the **Options** tab and enter a brief description in the text box.\n\n This optional description appears on the **Reports** page beside the report name.\n12. Click **Apply** to view the results, which Business Process Server displays in the **View Report** page.\n\n13. Refine the results, if necessary, and then click **Apply** to view the new result in the **View Report** page.\n\n In this page, you can click the instance name from the Name column to see the **View Dataslot** page of the selected instance. Click **Cancel** to close the **View Dataslot** page and go back to the **View Report** page. Click **Cancel** to close the **View Report** page and go back to the **Query** dialog window.\n\n14. To create a new report, click **Save As**.\n\n15. In the **Save As** dialog box, enter a name for the new report in the Report Name box and click **Save**.\nFigure 29: Saving a Query to Create a Report\n\nNote: Business Process Server cannot display a report that includes the forward slash (/) in its name. Therefore, it is recommended that it should not be used in the report name.\n\n16. Click Close to exit the Report Builder.\n\nBusiness Process Server displays all saved reports for the selected report type and the selected application in the Select a Report panel.\n\nCreating Multiapplication reports\n\nThis section describes how to use Business Process Server’s Report Builder to define new queries and create reports of application and task instances from multiple applications. After first defining a new query, the user can then save the defined query as a new report.\n\nNote: See Creating External reports on page 75 for more information on defining a query and creating External Reports.\n\nTo define a new query for multiple applications:\n\n1. From the Report List page, select Multiapplication Report from the drop-down list at the top of the page.\n\n Refer Creating and executing reports in Business Process Portal on page 65.\n\n Selecting Multiapplication Report enables you to create a report from all or multiple installed applications.\n\n\n3. Select one of the applications for which you want to create a report from the Unselected Applications panel and click Add to add it to the Selected Applications panel.\n\n4. Click Add All to add all the applications listed in the Unselected Applications panel to the Selected Applications panel. Click Remove or Remove All to delete one or all of the applications listed in the Selected Applications panel.\n\nNote: The list of selected applications including delimiters should not exceed 4000 characters.\n5. Click **Query** to display the **Query** dialog window.\n\nRefer Figure 33 on page 76.\n\nBusiness Process Server selects the Application Report type and the Application Attributes tab by default. The list of attributes shown in this Multiapplication Attributes tab may differ from the attributes associated with a single Query report (for a single application).\n\n6. Follow procedures described in steps 5-16 in Creating Application (Query) reports on page 68 to complete the creation of a multiapplication report.\n\n**Defining Parameters for Application and Multiapplications reports**\n\nBusiness Process Server’s Management module enables you to create parameters for application attributes, generating dynamic reports based on values that can be specified at the time the report is executed. After defining one or more parameters, Business Process Server prompts you to supply these values when you execute the query or report.\n\n**To define a new parameter, complete the following steps:**\n\n1. In the **Query** dialog window, click the Filters tab, then **Define Parameter**, to open the **Define Parameters** dialog window.\n\nRefer to Figure 30 on page 73.\n\n**Figure 30: Define Parameters Dialog Window**\n\n![Define Parameters Dialog Window]\n\n2. Type the name of the parameter in the Name box and enter the corresponding user prompt.\n3. Enter a default value for the parameter.\n4. Click **Add** to register the parameter. The parameter appears in the Current Parameters panel, and can be used for the current report or any future report.\n\nWhether creating a query or modifying a report, you can define parameters of report filters that generates reports based on a specific set of selected data.\nDefining parameters for report filters\n\nTo define parameters for report filters, complete the following steps:\n\n1. In the Query dialog window, click the Filters tab.\n2. Select attributes of the filter parameter from the Select Attributes panel.\n3. Set the Use Parameter checkbox.\n4. Click Select Parameter.\n\nBusiness Process Server displays available parameters in the drop-down list illustrated below.\n\nFigure 31: Selecting a Filter Parameter\n\n5. Select a parameter from the Select Parameter drop-down list.\n6. Click Add.\n\nBusiness Process Server adds the filter parameter to the list displayed in the Current Filters panel.\n\n7. Click Save to save the report.\n\n**Note:** While executing the query or report, a prompt appears to supply the defined parameter. Enter the value and click Go to generate the report.\nReport Versioning\n\nYou can run a multiapplication report on an application that has more than one versions. You can save this report. If you add more versions of this application, then the multiapplication report automatically reports on each added version, but only when these versions have the same application name; for example, Approval_V4, Approval_V5, Approval_V6.\n\nCreating External reports\n\nBusiness Process Server enables you to integrate externally defined reports. Use the Business Process Server Report Builder to create external reports that can access and execute reports using external report servers.\n\nTo define an External report, complete the following steps:\n\n1. From the **Report List** page, select **External Report** from the **Report** drop-down list at the top of the page.\n\n Selecting External Report enables you to create a report that can access and execute reports using external report servers.\n\n2. Click **Add Report**, and the **Add External Report** page opens.\n\n **Figure 32: Add External Report page**\n\n3. Select the generator of the report from the **Type** drop-down list. Options include Crystal, HTML, and BPM SQL. See Table 13 on page 67 for a description of the External report types.\n\n4. Click **Query**. Business Process Server displays the **Query** dialog window opened by default to the Custom Report tab. You can change the report generator, if required, using the Report Type drop-down list.\n5. When creating HTML reports, enter the URL of the HTML server in the **Report URL** box. For HTML, the default URL button is enabled only when the value is available in the `.conf` file; otherwise the Default URL button is disabled and therefore cannot be used as a basis for creating the reports.\n\n6. When creating Crystal Reports, enter the URL of the Crystal Report server in the **Report URL** box. Alternately, click the **Default URL** button to have Business Process Server fill in the default Crystal Report Server specified in the `bpmportal.conf` configuration file, if available.\n\n7. When creating BPM SQL reports, specify a file name instead of a URL in the Filename box. This file contains the SQL statements for execution by Business Process Server. The BPM SQL files are in the `<App_Server>\\sbm.war\\BizManage\\reports` directory. The file extension is `*.BizSQL`, which works for all databases. The path to the BPM SQL file depends on the application server you are using.\n \n See Figure 35 on page 79.\n\n---\n\n**Note:** If you want to include the Chart View in your BPM SQL report, then your query must contain following parameters from Business Process Server database:\n\n```\nprocess_template_name, process_template_id, process_instance_name and process_instance_id\n```\n\nNote the following conditions when using BPM SQL syntax:\n\na) You must use the exact syntax when developing BPM SQL reports. The following parameterized SQL query is provided as an example:\n\n```\nselect * from processinstance where processinstance.creator = '<%= who %>'\n```\nwhere the parameter value must be enclosed within the `<%= %>` tag, and you must enter a space before and after the query name. The tag must also be enclosed with single quotes. Optionally, you may also use non-parameterized SQL queries, the syntax for which is as shown in the following examples (in these examples, * = all):\n\n```\nSelect * from processinstance where processinstance.creator IN '<%= who %>'\nSelect * from processinstance where processinstance.creator = '<%= who %>'\nSelect * from processinstance where processinstance.creator NOT '<%= who %>'\n```\n\nPlease make sure that you enter the SQL query as is shown in the above examples with appropriate changes as per your requirements.\n\nb) Do not put a semicolon at the end of the SQL statement; it causes an invalid character error.\n\nc) Use the following syntax when you want to display a valid field under a customized label in Business Process Portal:\n\n```\nselect field1 AS label1, field2 AS label2, field3 as label3,... from table name\n```\n\nor in a specific example:\n\n```\nSelect PROCESSINSTANCE.PROCESSINSTANCENAME AS Task from PROCESSINSTANCE\n```\n\nwhere `PROCESSINSTANCE.PROCESSINSTANCENAME` is the field, `Task` is the label and `PROCESSINSTANCE` is the table name.\n\n8. To define parameters for External reports:\n\na) Enter a parameter name and value in the **Parameter Name** and **Parameter Value** boxes respectively, and click **Add**. Use these parameters to uniquely identify the report.\n\nb) Business Process Server adds the parameter definition to the **Current Parameters** drop-down list.\nc) To add more parameters, repeat the preceding steps.\n\nd) To remove a parameter, select it from the \\textbf{Current Parameters} drop-down list and click \\textbf{Remove}.\n\n9. When using BPM SQL as the report generator, Business Process Server substitutes the parameters into the file containing SQL statements, enabling you to define parameterized SQL statements. When entering parameters and values, follow the SQL syntax. For example, in the \\textbf{Parameter Name} box, use the following format to enter parameter names in the BPM SQL query file:\n\n\\begin{verbatim}\nparameter_name or 'parameter_name'\n\\end{verbatim}\n\nAs shown in the example above, the parameter value may be given without single quotes or within single quotes, depending on the SQL syntax. For example, if the parameter's value is part of a Where clause, then it is in single quotes.\n10. Click the Options tab and enter a description of the new report in the Description text box. This description appears on the Report List page beside the report name.\n\nSee Figure 36 on page 80.\nChapter 6: Executing and creating reports\n\nFigure 36: Adding a Report Description\n\n11. Click **Apply** to view the results, which Business Process Server displays in the Report Parameters window.\n\n12. Refine the results, if necessary, and then click **Submit** to view the new results in the **View Report** page.\n\n In this page, you can click the instance name from the Name column to see the Chart View of the selected instance. Click **Cancel** to close the Chart View and go back to the **View Report** page. Click **Cancel** to close the **View Report** page and go back to the **Query** dialog window.\n\n13. Click **Save As** to open the **Save As** dialog box (see below) to create a new external report.\n\n **Figure 37: Saving a Query to Define a Report**\n14. Enter a name for the new report in the Report Name box and click **Save**. Do not use the forward slash (/) character in a report name. Business Process Server cannot display a report that includes ‘/’ in its name.\n\n15. Click **Close** to exit the Report Builder.\n\nBusiness Process Server displays all saved reports on the **Report List** page for the selected report generator.\n\nAs shown in Figure 37 on page 80.\n\n---\n\n**Modifying an existing report**\n\nMany of the same procedures that were used to create a new Query (Application), Multiapplication or External report can be used to modify an existing report.\n\n**To modify an existing report:**\n\n1. In the Management module, click **Reports > My Reports**, to view the **Report List** page, and then select a report from the Report Name column.\n\n Refer to Creating and executing reports in Business Process Portal on page 65 for more information.\n\n2. Click **Edit Report** (Chart) icon, displayed in the Report Name column, and a window displaying existing settings for the selected report opens.\n\n3. Follow the procedures, as necessary, in steps 3 - 14 in Creating Application (Query) reports on page 68 or in steps 4 - 16 in Creating External reports on page 75.\nRemoving an Existing report\n\nTo delete an existing report, navigate to the **Report List** page. Select the report to be deleted from those listed on the page, and click **Delete**.\n\nRefer **Creating and executing reports in Business Process Portal** on page 65.\n\nTask Filtering for reports\n\nBusiness Process Server provides extended task filtering capabilities for more effective report building. Using task filtering, managers can create reports filtered on task attributes. Managers are able to define complex task reports through the existing Business Process Portal interface, and don’t need to navigate to the BPM SQL report facility.\n\n*Note*: The task filter cannot entirely replace the BPM SQL report facility, which can manipulate any database table, not just the workstep and work item tables.\n\nFor example, you can specify which tasks are to be displayed, and can choose from all the tasks of a particular instance to none of the tasks of a particular instance. The Report Builder supports the definition of filters on the following task items:\n• Task name\n• Creator\n• Task status\n• Task priority\n• Task start/end time\n\nThe task filtering feature is built into the Report Builder interface on the Report List page. With task filtering built into the interface, you can specify conditions of any task attribute and not lose the previous capabilities, such as filtering process instances based on the priority of a particular workstep.\n\nFor example, the manager of a Hiring application can list all the instances with an Evaluate Resume task that has an Active status and a High priority. Furthermore, if the report was defined as a task report, then the list of worksteps that are only active is displayed, as well as all tasks (active as well as completed, removed and suspended) related to the instances.\n\nUsing Task Filtering for Reports\n\nTo use task filtering in reports:\n\n1. For new reports, from the Report List page, click Add Report. Select appropriate options from the Type and Applications panels, and click Query. For existing reports, select the report you want to revise and click Edit Report icon.\n\n2. The Query dialog window appears, open to the Application Attributes tab. Select Task Report from the Report Type drop-down list in the Query dialog window.\n3. From the tasks listed in the right panel of the Query dialog window, select the tasks to be displayed in the report.\n\n4. From the attributes listed in the left panel of the Query dialog window, select the work item attributes to be displayed in the report.\n\n5. Click the Filters tab.\n\nRefer Figure 39 on page 84.\n\nTo define a filter for work item attributes, select an attribute from the Select Attributes panel. Each time the user selects one of the attributes, the contents of the Define Filter panel changes. Type a reference value into the text box in the Define Filter panel, or click the ellipsis button ( ) beside the text box to let the Report Builder display a list of available values. After defining the filter, click Add. Business Process Server adds the filter to the list in the Current Filters panel. Add additional work item attribute filters as required.\n\nTo define a filter for task attributes, select an attribute from the Task Attributes panel in the lower left of the page.\n\nRefer Figure 39 on page 84.\n\nEach time the user selects one of the task attributes, the contents of the Define Contents panel changes. Enter appropriate information in the Define Filter panel. After defining the filter, click Add. Business Process Server adds the task attribute filter to the list in the Current Filters panel. Add additional task attribute filters as required.\n\n**Note:** In the case of task reports, you can find another option, <Any Task>, in the work item sub-panel to define a filter on a task attribute independent of the work item name.\n6. Click the **Options** tab. Enter a brief description of the report in the activated text box. The description appears on the **Reports** page beside the report name.\n\n7. Click **Save As** when all task report filters have been defined.\n8. Enter the name of the new report in the **Save As** dialog window, and click **Save**.\n9. Click **Close** to exit the Report Builder.\n\nBusiness Process Server displays all saved reports on the **Report List** page.\n\nRefer to sCreating and executing reports in Business Process Portal on page 65.\n\n**Updating previously created reports with Task Filtering**\n\nIt is possible to open a report created in an earlier version of Business Process Server and add the task filtering functions to the report.\n\n**Defining Infopad Reports**\n\nBPM Events uses a data structure called an infopad to store:\n\n- Application parameters (for example, the list of product purchase limits for different departments)\n- Rule parameters (for example, the critical threshold for a resource load)\nAny other global data that the rules may require.\n\nInfopads are stored in the Business Process Server repository. An infopad is a single- or two-dimension table, which is composed of cells. Each cell is a data structure that contains a cell slotname and a value. For more detailed information on infopads, see the *Infopads* chapter in the *BPM Events User's Guide*.\n\nBusiness Process Server enables you to create a detailed analysis report of an infopad associated with one or more applications. These reports are called infopad reports.\n\nIn the **Report List** page, select Infopad Report from the list adjacent to the Add Report button. You can then perform the following actions on the infopad reports.\n\n**Table 14: Infopad Report Actions**\n\n<table>\n<thead>\n<tr>\n<th>Option</th>\n<th>Action</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Add Report button</td>\n<td>Create a new infopad report.</td>\n</tr>\n<tr>\n<td>Edit Report icon</td>\n<td>Modify an existing infopad report.</td>\n</tr>\n<tr>\n<td>Delete button</td>\n<td>Delete the selected infopad report.</td>\n</tr>\n<tr>\n<td>View button</td>\n<td>Display the selected infopad report.</td>\n</tr>\n</tbody>\n</table>\n\nBusiness Process Server offers a highly visual set of charts for infopad reports, which can help you monitor Business Process Server applications at a higher level. Select from one of the following analysis formats:\n\n- Table\n- Graph\n- Table & Graph\n- Excel Spreadsheet\n\n**To create a detailed analysis report using infopads, complete the following steps:**\n\n1. In the **Report List** page, select **Infopad Report** from the drop-down list, and then click **Add Report**. The **Add Application(Infopad) Report** page opens.\n2. Specify the information and format for the infopad report. The following table lists infopad report options:\n\n**Table 15: Infopad Report Options**\n\n<table>\n<thead>\n<tr>\n<th>Option</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Application</td>\n<td>Select an application for which you want to create a report.</td>\n</tr>\n<tr>\n<td>Report Name</td>\n<td>Specify a name for the report.</td>\n</tr>\n<tr>\n<td>Report title</td>\n<td>Specify the title that is displayed on the infopad report.</td>\n</tr>\n<tr>\n<td>Report description</td>\n<td>Specify the description that is displayed on the infopad report.</td>\n</tr>\n<tr>\n<td>Infopad</td>\n<td>Select the infopad you want to analyze from the drop-down list.</td>\n</tr>\n<tr>\n<td>Row and Column</td>\n<td>Business Process Server automatically chooses a row and column for the report when you select the infopad, but you can change these default selections.</td>\n</tr>\n<tr>\n<td>Slice on</td>\n<td>Business Process Server automatically chooses the dataslot displayed in the infopad composer, but you can change the default selection.</td>\n</tr>\n<tr>\n<td>Chart type</td>\n<td>Choose from the following: Line Chart, Pie Chart, Area Chart, Multi-row Bar Chart, Multi-column Bar Chart, Stacked Bar Chart, or Stacked Area Chart.</td>\n</tr>\n<tr>\n<td>Pie Chart On</td>\n<td>Select Row or Column, when the Pie Chart option was selected in the Chart Type drop-down list.</td>\n</tr>\n<tr>\n<td>Option</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-----------------</td>\n<td>---------------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>Default view</td>\n<td>Choose from the following: Table, Graph, Table & Graph, or Excel.</td>\n</tr>\n<tr>\n<td>Layout</td>\n<td>Choose either Horizontal or Vertical. The layout option applies only to Table & Graph views.</td>\n</tr>\n<tr>\n<td>3D</td>\n<td>Check to display the analysis in 3D charts. The three-dimensional effect does not apply to any area or stacked area chart types.</td>\n</tr>\n<tr>\n<td>Value</td>\n<td>Business Process Server automatically chooses the numerical value for the row or column when using the pie chart, but you can change the default selection.</td>\n</tr>\n<tr>\n<td>Width and Height</td>\n<td>Business Process Server automatically chooses the physical size of the infopad report, but you can change the default selection.</td>\n</tr>\n</tbody>\n</table>\n\nTo show your data correctly in the selected Chart type, you must define more than one row or column in either the row dimension or the column dimension. To display the Area Chart and Stacked Area Chart types correctly for infopads, make sure that you select an option from the Column drop-down list that contains at least one row and more than one columns.\n\n**Note:** You can use the Permission Create page in the Administration module to control the permissions to multiple infopads. For more information on BPM Events security, see the *Business Process Portal Administrator's Guide*.\n\n3. Click **Preview**. A new window opens, displaying the Infopad Report based on the specified settings. Click the **Graphical View** tab, to verify whether your infopad report presents the data as required or not. Click **Close this window** to return to the Add Application (Infopad) Report page.\n\n4. Click **Save** to save the current report. Click **Save & Add New** to save the current report and reload the page to allow you to add another report.\n\n Click **Reset** to delete your changes and display the original settings.\n\n Click **Cancel** to delete your changes and return to the previous page.\nUsing the Instance Manager\n\nIn today's business environment, a system may have hundreds of performers creating thousands of instances. As a user in this type of system, you may want to modify large numbers of instances, worksteps and tasks in batches, rather than on a more time-consuming, one-by-one basis. The Instance Manager enables you to efficiently manage existing instances and their tasks in batches, by performing the following procedures:\n\n• **Search through all existing instances and their tasks.** Use the Instance Manager's Search function to filter through instances and tasks for date, name, creator, and priority attributes.\n\n• **Update batches of process instances and worksteps.** All instances or worksteps, system attributes or dataslots retrieved by the Instance Manager's Search function can be updated with a single click.\n\n• **Dynamically change instance properties at run-time.** Instance Manager enables you to change application properties at the instance level and the task level, even when the application is up and running. You can change instance and task properties or change attribute or dataslot values at run-time.\n\n**Note:** Instance Manager only works with existing instances and their tasks. To change template-level properties at run-time, you must use other Management features.\n\n• **Perform bulk updates of instances in Management reports.** You can quickly update selected groups of user defined dataslots.\n\n• **Reassign tasks in batches.** In some systems, you, as a Manager, can create hundreds of instances of an application, which are automatically assigned to you. You can then use the Instance Manager to reassign all or a selected batch of tasks to a specific performer. In case of employees on vacation or leaving the company, you can also reassign batch of these tasks to a specific performer.\n• **Assign \"Available Status\" tasks to specific performers.** In Business Process Server, if the performer of a task is a group and the role is \"any\", then the status of this task is \"Available\" to any member of the group until it is actually assigned to a specific performer. Using Instance Manager, you can conveniently retrieve such groups of tasks and assign a batch of them to a specific performer or to another group.\n\nFor details, see the following topics:\n\n• **Launching the Instance Manager**\n• **Reassigning Assigned Tasks**\n• **Reassigning Available Tasks**\n• **Updating Worksteps**\n• **Resuming Suspended Worksteps**\n\n### Launching the Instance Manager\n\nThe Instance Manager feature can be described as a Web Application running in the Management module. To launch the Instance Manager from the Management module of Business Process Portal, in the Management module, click the **Instance Manager** menu and select one of the submenu options.\n\nIn order for the Instance Manager to function, Business Process Server must be running. When you start Instance Manager, it first verifies that Business Process Server is running. If it is not running, then it displays a warning message. When this warning is displayed, you must log out of Business Process Portal, launch Business Process Server, and log in to Business Process Portal, and then access Instance Manager again.\n\nInstance Manager enables you to select the application that you want to monitor or manage. You can only select one application in the Instance Manager.\n\nThe Instance Manager enables you to manage at the following levels:\n\n• **Instance Level**, where you can:\n • Click **Search Criteria** to search for and view a list of process instances, and change one, a selected batch, or all process instance properties in the selected application.\n • Click **Display Attributes** to modify dataslots in the selected application.\n • Click **Reports** to modify system attributes in BPM Manage API reports in the selected application.\n\n• **Task Level**, where you can:\n • View the tasks for all performers, or search a specific performer.\n • Reassign one, a selected batch, or all assigned tasks of a performer, or reassign the available tasks of a performer.\n\n• **Workstep Level**, where you can:\n • Click **Search Criteria** to search for a specific, or a selected group of worksteps.\n • Click **Worksteps** to update all, or selected worksteps.\n• Click **Display Attributes** to modify workstep attributes of the selected application.\n\n### Updating Process Instances\n\nTo update one process instance, a selected batch of process instances, or all process instances:\n\n1. In the Management module, click **Instance Manager > Instances**, to view the **Search Instances** page.\n\n **Figure 42: Search Instances Page**\n\n \n\n2. Select an application from the **Application** drop-down list at the top of the **Search Instances** page. To further define your search on a specific attribute, select the **Attributes** option, and click **Go**.\n\n The **Search Instances** page, contains the Search Criteria, and Display Attributes tabs. It enables you to refine your search.\n\n3. Click the **Search Criteria** tab, and enter relevant data in the **Instance Name**, **Creator**, **Priority**, **Start Date** and **Due Date** boxes.\n\n a) In the **Instance Name** box, enter the name of the Instance that you want to retrieve. Note that the search engine is case sensitive.\n\n By default, an asterisk (*) is entered, which means that all instances are displayed.\n\n b) In the **Creator** box, enter the name of the Creator that you want to retrieve in the text box. Note that the search engine is case sensitive. By default, an asterisk (*) is entered, which means that all creators are displayed. Alternatively, click the **Edit Creator** icon to open the **Search Users** page (for more information, see Searching Users on page 36).\n\n c) In the **Priority** box, select an option from the drop down list. The option \"All\" is selected by default.\n\n d) In **Start Date** and **Due Date** boxes, specify a time period from the options in the corresponding drop-down list. Alternatively, click the **Select Date** icon to set the respective start date or due date. For more details, see Specifying a Date on page 35. By default, all dates are specified.\n\n**Note:** If you use the defaults and make no entries on the **Search Instances** page, then a list of all active instances for the selected application is returned by default.\n4. Click the **Display Attributes** tab. It displays a list of dataslots. Select the check boxes for the dataslots that you want to change.\n\n**Note:** Dataslots of type Object, Map, and List are not displayed in the Display Attributes tab.\n\n5. Click **Search** to retrieve all instances that meet the search criteria you have specified.\n\n6. The search results are presented in the **Instance List** page.\n\nRefer **Figure 43** on page 92.\n\nThis page contains two frames: the top frame displays all instances you had selected in step 3 and dataslots that you had selected for display in step 4; and the bottom frame allows you to apply common values to selected dataslots. As seen in the top frame, instances are presented in a tabular format, with each row representing an instance. Instance name and dataslots are displayed in columns.\n\nIf no attributes are selected, then the **Instance List** page displays all the instances you have selected excluding the dataslot. It displays only **Remove**, **Remove All** and **Cancel** options.\n\n**Figure 43: Instance List Page**\n\nIf your search has retrieved many instances, then they are presented in multiple pages. To manage the contents of the list, you can sort them. To navigate through the pages, you can use the paging controls. For more details about these operations, see **Exploring Business Process Portal** on page 24.\n\n**Note:** You can customize the number of instances that are displayed on a single page by modifying the `bpmportal.page.size` property in `bpmportal.conf` file.\n\n7. To modify data for specific instances, click the link in the Instance column. The details of the selected instance are displayed in the bottom frame.\n a) Enter new information about the displayed dataslots in the corresponding value boxes for the instance(s).\n b) To apply common values to selected instances and/or clicked instance displayed in the top frame, make modifications to the dataslot values displayed in the bottom frame, and click **Apply**. You can also apply common values to all instances displayed on the page by selecting the checkbox in the heading of the table in the top frame.\n\nRefer **Figure 43** on page 92.\n\n c) Click **Save** to save the new data after your confirmation.\n8. Click **Update All** to apply common values to all instances displayed on all pages. A Warning appears, stating that all instances for the selected application is updated and asks do you want to continue. You cannot undo this operation, so make sure all information is correct. Click **OK** and a Confirmation message appears, indicating the update was successful. Click **OK** to return to the **Instance List** page.\n\nTo reset the form and remove the information you just entered, click **Reset**. To cancel the action and exit the current page, click **Cancel**.\n\n### Updating Instances Using Reports\n\nTo perform a bulk update of user defined dataslots that are in an existing report (i.e., a report that you have previously defined):\n\n1. In the Management module, click **Instance Manager > Instances**, to view the **Search Instances** page.\n2. Select an application from the **Application** drop-down list at the top of the **Search Instances** page. To further define your search on a specific report, select the **Reports** option, and click **Go**.\n\nBusiness Process Portal displays a list of ‘Application’ reports for the selected application.\n\nRefer **Figure 44** on page 93.\n\n**Note:** Dataslots of type Object, Map, and List are not displayed.\n\n3. Select a report, and click **Search**, to open the **Instance List** page.\n\n**Note:** Search does not list the reports designed in the Jasper Report, Multiapplication Report, External Report and Infopad Report Designer.\n\n**Figure 44: Reports List Page**\n\n4. Follow procedures similar to those described in steps 6 - 8 in **Updating Process Instances** on page 91.\nRemoving Instances\n\nAs a Manager, you can remove instances created by you as well as by others.\n\nTo remove instances:\n\n1. Follow the procedure described in steps 1 - 6 in the Updating Process Instances on page 91 to locate the instances for removal.\n2. If you want to remove only a few instances, select them from the top frame and then click Remove. To remove all instances, click Remove All.\n\nReassigning Assigned Tasks\n\nTo reassign one assigned task, a selected batch of assigned tasks, or all assigned tasks to specified performers:\n\n1. In the Management module, click Instance Manager > Tasks, to view the Performer List page.\n2. Select an application from the Application drop-down list.\n3. Select Assigned from the Task Type drop-down list, and click Go. The Performer List page is displayed.\n\nFigure 45: Performer List Page\n\nNote: The Performer List page displays only user and group performers. It does not display any performer for a task having queue as a performer.\n\n4. Before you reassign tasks, you need to select the performers whose tasks you want to reassign. To locate specific performers, use the search functions on the Performer List page.\n a) To search for all performers for a specific search criteria, enter an asterisk (*) in that search field.\n b) The asterisk also serves as a wild card for the Performer box. For example, you can search for users named McPherson by entering any of the following:\n • Mc* locates all performers with a name beginning in Mc.\n • *pher* locates all performers with names containing \"pher\".\n• “son” locates all performers with a name ending in “son”.\n\n• M*n locates all performers with names starting with M and ending with n.\n\nc) Click Search. The Reassign Assigned Tasks page is displayed.\n\n5. The Reassign Assigned Tasks page enables you to reassign an assigned task (i.e., change the performer property of a task). This page contains two frames: the top frame lists the specified performers for the selected application; the bottom frame enables you to select a common performer for all the instances listed in the top frame.\n\nFigure 46: Reassign Assigned Tasks Page\n\n6. On this page you can perform the following functions:\n\na) To reassign the selected task(s) to a common performer:\n\n• Select one or more specific task checkbox(es) in the top frame.\n You can select the checkbox in the column header to select all the tasks on the current page.\n\n• Enter a performer’s name in the Common Performer box or use the Edit Performer icon ( ) to open the Search Users page, where you can search for, then add, a specific performer.\n\n• Click Apply. The selected tasks are reassigned to the specified performers after your confirmation.\n\n• Click Save. Business Process Server saves the current settings.\n\nb) To reassign all task(s) across all pages to a common performer:\n\n• Enter a performer’s name in the Common Performer box or use the Edit Performer icon ( ) to open the Search Users page, where you can search for, then add, a specific performer.\nReassigning Available Tasks\n\nIf the performer of a workstep is a list of names or a group with the role of \"any\", then its tasks have an Available status when they are created, and remain in this status until you assign them to a specific performer.\n\nTo reassign one available task, a selected batch of available tasks, or all available tasks to specified performers:\n\n1. In the Management module, click Instance Manager > Tasks, to view the Performer List page.\n2. Select an application from the Application drop-down list.\n3. Select Available from the Task Type drop-down list, and click Go. The Performer List page is displayed.\n\n4. Before you reassign tasks, you need to select the performers whose tasks you want to reassign. To locate specific performers, use the search functions on the Performer List page. After selecting a user, click Search.\n5. The Reassign Available Tasks page enables you to reassign an available task. This page contains two frames: the top frame lists the specified performers for the selected application; the bottom frame enables you to select a common performer for all the instances listed in the top frame.\n6. The procedures for reassigning available tasks are very similar to procedures described in step 6 in Reassigning Assigned Tasks on page 94.\n\nUpdating Worksteps\n\nYou can now update data at the workstep level. The bulk update feature for worksteps allows you to enter search criteria for instances, select specific worksteps and choose which dataslot attributes are displayed.\n\nTo update one workstep, a selected batch of worksteps, or all worksteps:\n1. In the Management module, click **Instance Manager > Worksteps**. The **Search Worksteps** page is displayed.\n\n2. The **Search Worksteps** page contains three tabs: Search Criteria, where you can select one or more instances; Display Attributes, where you can choose which dataslot attributes will be displayed; and Worksteps, where you can select one or more worksteps.\n\n **Figure 47: Search Worksteps Page**\n\n3. Select an application from the **Application** drop-down list, and click **Go**.\n\n4. The **Search Worksteps** page has a format similar to the **Search Instances** page. Please refer to the procedures described in **Updating Worksteps** on page 96 in **Updating Process Instances** on page 91.\n\n5. Use the Search Criteria tab to specify search criteria that locates and display worksteps of the selected application that meet the search criteria. Ensure that you have selected **Activity** from the Workstep Type drop-down list.\n\n6. Open the **Display Attributes** tab to display a list of workstep attributes. Select the check boxes for the workstep attributes that you want to change.\n\n7. Open the **Worksteps** tab to specify the worksteps you want to locate.\n\n8. Click **Search** to retrieve all work items that meet the search criteria you have specified.\n\n9. The search results are presented in the **Workstep List** page Step **Figure 48** on page 98. This page contains two frames: the top frame displays all worksteps selected in step 5, and identifies their associated instance as well as workstep attributes that you had selected for display in step 6. The bottom frame allows you to apply common values to selected workstep attributes. Only for the following workstep attributes you can change the value:\n\n - Next Activation Performer\n - Status\n - Priority\n - Due Date\n\nAs seen in the top frame, worksteps are presented in a tabular format, with each row representing a workstep. Workstep values are represented as columns.\nIf your search has retrieved many worksteps, then they are presented in multiple pages. To manage the contents of the list, you can sort them. To navigate through the pages, you can use the paging controls. For more details about these operations, see Exploring Business Process Portal on page 24.\n\n**Note:** You can customize the number of worksteps that are displayed on a single page by modifying the `bpmportal.conf` file.\n\n10. To modify data for the selected worksteps, click the link in the Instance column. The details of the selected workstep are displayed in the bottom frame.\n a) Enter new information about the displayed dataslots in the corresponding value boxes for the workstep(s).\n\n **Note:** If you change the performer from the Workstep List page, then this change is effective only when that workstep is reactivated. Therefore, it is recommended not to change the performer from this page. You should do this change from the Performer List page. For more information, see Reassigning Assigned Tasks on page 94.\n\n b) To apply common values to selected instances and/or clicked instance displayed in the top frame, make modifications to the dataslot values displayed in the bottom frame (see ), and click **Apply.** You can also apply common values to all instances displayed on the page by selecting the checkbox in the heading of the table in the top frame.\n\n Refer Step Figure 48 on page 98.\n\n c) Click **Save** to save the new data after your confirmation.\n\n To reset the form and remove the information you just entered, click **Reset.** To cancel the action and exit the current page, click **Cancel.**\n\n11. Click **Update All** to apply common values to all instances displayed on all pages. A Warning appears, stating that all instances for the selected application is updated and asks do you want to continue. You cannot undo this operation, so ensure all information is correct. Click **OK** and a Confirmation message appears, indicating the update was successful. Click **OK** to return to the Workstep List page.\n\n12. To reset the form and remove the information you just entered, click **Reset.** To cancel the action and exit the current page, click **Cancel.**\nResuming Suspended Worksteps\n\nYou can resume the suspended workstep(s).\n\nTo resume one workstep, a selected batch of worksteps, or all worksteps:\n\n1. In the Management module, click Instance Manager > Worksteps. The Search Worksteps page is displayed.\n\n2. The Search Worksteps page contains three tabs: Search Criteria, where you can select one or more instances; Display Attributes, where you can choose which dataslot attributes is displayed; and Worksteps, where you can select one or more worksteps.\n\nFigure 49: Search Worksteps Page\n\n3. Select an application from the Application drop-down list, and click Go.\n\n4. The Search Worksteps page has a format similar to the Search Instances page. Please refer to the procedures described in Updating Worksteps on page 96 in Updating Process Instances on page 91.\n\n5. Use the Search Criteria tab to specify search criteria that locates and display worksteps of the selected application that meet the search criteria.\n\nDepending on whether you want to resume worksteps to which human performers or adapters are assigned, select Activity or Adapter/Agent respectively from the Workstep Type drop-down list\n\n6. Open the Display Attributes tab to display a list of attributes and dataslots. Select the check boxes for the attributes and/or dataslots that you want to change.\n\n7. Open the Worksteps tab to specify the worksteps you want to locate.\n\n8. Click Search to retrieve all work items that meet the search criteria you have specified.\n\n9. The search results are presented in the Workstep List page. This page contains two frames: the top frame displays all worksteps selected in step 5, and identifies their associated instance as well as dataslots that you had selected for display in step 6. The bottom frame allows you to apply common values to selected dataslots.\n\nRefer Step Figure 50 on page 100.\n\nAs seen in the top frame, worksteps are presented in a tabular format, with each row representing a workstep. Workstep values are represented as columns.\nIf your search has retrieved many worksteps, then they are presented in multiple pages. To manage the contents of the list, you can sort them. To navigate through the pages, you can use the paging controls. For more details about these operations, see Exploring Business Process Portal on page 24.\n\n**Note:** You can customize the number of worksteps that are displayed on a single page by modifying the `bpmpportal.conf` file.\n\n10. In the top frame, select the worksteps whose status is to be changed to Resume.\n11. In the bottom frame, select **Active** from the **Status** drop-down list, and then click **Apply**. You can also change the status of all instances displayed on the page by selecting the checkbox in the heading of the table in the top frame.\n12. Click **Save** to save the new data after your confirmation.\n\n To reset the form and remove the information you just entered, click **Reset**. To cancel the action and exit the current page, click **Cancel**.\n\n13. Click **Update All** to apply common values to all instances displayed on all pages. A Warning appears, stating that all instances for the selected application are updated and asks if you want to continue. You cannot undo this operation, so make sure all information is correct. Click **OK** and a Confirmation message appears, indicating the update was successful. Click **OK** to return to the **Workstep List** page.\n14. To reset the form and remove the information you just entered, click **Reset**. To cancel the action and exit the current page, click **Cancel**.\nUsing the Balanced Scorecard\n\nBalanced Scorecard is a performance management system that enables senior management to measure how their organization’s business activities are helping it meet its strategic goals. Balanced Scorecard provides you a Manager with a method of statistically measuring your company's performance, using a scale of 0-10, resulting in a balanced, high-level view of all areas of your enterprise.\n\nFor details, see the following topics:\n\n- Using the Balanced Scorecard Designer\n- Using the Balanced Scorecard\n\nUsing the Balanced Scorecard\n\nBalanced Scorecard enables you to look at your strategic goals from not just one, but a range of, perspectives that typically include:\n\n- **Finance.** Presents data from the perspective “To succeed financially, how do we appear to our shareholders?”\n- **Customer.** Presents data from the perspective “To achieve our strategic goals, how do we appear to our customers?”\n- **Innovation.** Presents data from the perspective “To achieve our strategic goals, how are we sustaining our ability to change and improve?”\n- **Internal.** Presents data from the perspective “To satisfy our shareholders and customers, what business processes must we excel at?”\nEach of these Balanced Scorecard Perspectives are derived from key performance indicators (KPIs) that provide the data that translate enterprise goals into a set of measurable objectives. For example, the Finance Perspective can contain such KPIs as Product Revenue, Service Revenue, Product Revenues Growth, Service Revenues Growth, Profit Margin and Sales Pipeline. Each of these KPIs can be assigned a weight that indicates its comparative significance.\n\n**Combining Business Process Server and Balanced Scorecard**\n\nThe Management module of Business Process Portal provides business process management at the business unit or department level, and the Balanced Scorecard is also typically management focused, even though you can drill down through the organization. The combination of Business Process Server and Balanced Scorecard provides a unique business approach that enables you to compare Business Process Server’s business process intelligence against the measurement of corporate strategy achievement supplied by Balanced Scorecard.\n\nBusiness Process Server’s Management module enables its users to perform such Balanced Scorecard management processes as:\n\n- Establishing performance targets, either by using the predefined KPIs discussed above or by using the Balanced Scorecard Designer to create customized KPIs that more accurately reflect your organization’s requirements.\n- Integrating with external systems to collect relevant data, and effectively monitoring business processes through standard or customized KPIs.\n- Measure the contribution business processes are making in achieving business objectives and strategic goals.\n\nEach of the Balanced Scorecard Perspectives are derived from key performance indicators (KPIs). Each of these KPIs can be assigned a weight that indicates its comparative significance. In the Balance Scorecard console view, each KPI value is displayed as a dial. This dial displays the target score along with the actual score for each KPI. The target score divides the circumference of the dial into two parts; the first part, that is, the arc from 0.0 to target score is shown in red, whereas the second part, that is, the arc from target score to 10.0 is shown in green. The needle of the dial indicates rounded-off actual score. Optionally, the fields below the dial show the exact actual value and/or target score. This dial gives a visual indicator of achievements and help managers to track the progress.\n\n**Viewing Balanced Scorecard Applications**\n\nBusiness Process Server contains processes and rules that collate Business Scorecard data and it then inserts this data in infopads. Business Process Server enables you to view this data as a standard Balanced Scorecard application, or to design a customized Balanced Scorecard application.\n\nThe user must install the Balanced Scorecard sample application, and then select Balanced Scorecard from the drop-down list on the Balanced Scorecard page to display the standard view. By default, a view of all the perspective values is displayed.\n\nRefer Figure 51 on page 103.\n\n**To view your Balanced Scorecard application:**\n\n1. In the Management module, click **Balanced Scorecard > Console**. The Balanced Scorecard page.\n2. Select an option from the **Balanced Scorecard** drop-down list, select an option from the **Perspective** drop-down list, and then click **Go** to obtain information on a specific Balanced Scorecard Perspective. Options include All, Customer, Finance, Innovation and Internal.\n\n3. Edit values for each perspective by clicking the **Edit** icon ( ). For more information, see **Editing Balanced Scorecard Perspectives** on page 104.\n\n4. In the console view, each KPI value is displayed as a dial. Each dial is associated with a link to infopad analysis reports that launch a history for the selected KPI. For example, clicking the Product Returns dial of the Customer perspective displays the report. Click on any of the KPI links to execute a corresponding analysis report.\n\n**Figure 52: Balanced Scorecard History**\nEditing Balanced Scorecard Perspectives\n\nBusiness Process Server provides a management application interface in which the user can edit the Relative Weights for a specific KPI, as well as modify other values and enter a description of each KPI in the selected perspective.\n\nThis interface is seen in Figure 53 on page 104.\n\nFor example, you can emphasize the importance of Profit Margin KPI in the Finance Perspective by increasing the original value of 0.2 (20%) to a value of 0.70 (70%) in the Weight column. Changing the relative weight of the Profit Margin KPI changes the score for the Finance Perspective, as well as the total Balanced Score.\n\n**Note:** The sum of the numbers in the Edit (Perspective) **Relative Weights** dialog window must not exceed 1.0.\n\nRefer Figure 53 on page 104.\n\nTo edit a Balanced Scorecard value:\n\n1. Click the **Edit** icon (displayed to the right of each Perspective to open the **Perspective Details** page.\n\n **Figure 53: Editing Balanced Scorecard Perspectives**\n\n \n\n2. Modify the data in any of the boxes.\n\n3. Click **Save** to submit and save your changes. A Confirmation message appears, indicating the editing of the perspective values was successful. Click **OK**, and return to the **Balanced Scorecard** page.\n\n Click **Reset** to delete your changes and display the original settings.\n\n Click **Cancel** to delete your changes and return to the **Balanced Scorecard** page.\nUsing the Balanced Scorecard Designer\n\nBusiness Process Server provides the Balanced Scorecard Designer, which presents a series of user interfaces where you can view your available Balanced Scorecard applications, modify existing Balanced Scorecards, and add a new Balanced Scorecard application that meets your specific requirements.\n\nDesigning a New Balanced Scorecard\n\nTo design a new Balanced Scorecard:\n\n1. In the Management module, click Balanced Scorecard > Designer, to open the Balanced Scorecard List page.\n\n Figure 54: Balanced Scorecard List Page\n\n ![Balanced Scorecard List Page]\n\n All available Balanced Scorecard applications are listed, with respective status and a brief description for each of them.\n\n The status column indicates the state of the Balanced Scorecard:\n\n - The green icon indicates a valid Balanced Scorecard and it is listed in the BP Server Applications page in the Administration module.\n - The red icon indicates that the Balanced Scorecard is not defined properly or its rules are not compiled. You must resolve these issues to add this in the BP Server Applications page.\n\n2. To add a new Balanced Scorecard, click Add Balanced Scorecard, to open the Add Balanced Scorecard page.\nFigure 55: Add Balanced Scorecard Page\n\na) Enter the name of the new Balanced Scorecard and its description. Both these are required fields.\n\nb) Click Next, to open the Perspectives List page where you can create perspectives for the new Balanced Scorecard.\n\n3. The Perspectives List page enables you to:\n\nFigure 56: Add Perspective Page\n\na) Enter a name in the Perspective box and assign the perspective a weight.\nNote: The perspective name must not contain spaces.\n\nb) You may add more perspective(s), when required, by clicking Add Perspective, which opens Add Perspective window. Enter perspective and weight and click Save to add the perspective to the Perspective/Weight table.\n\nc) Click Next, to open the Source List page where you can define sources to be used by the KPIs of the new Balanced Scorecard.\n\n4. The Source List page enables you to add sources of information that can be used to define KPIs and generate Balanced Scorecards. All KPIs must have at least one source, and Additive and Averaging KPIs can have multiple sources. This page displays two tables listing the Process Template Sources and the Infopad Sources.\n\nFigure 57: Source List Page\n\n<table>\n<thead>\n<tr>\n<th>Process Template Sources</th>\n<th>Infopad Sources</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>No.</td>\n<td>Source</td>\n</tr>\n<tr>\n<td>1</td>\n<td>Test</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>No.</th>\n<th>Source</th>\n<th>Application</th>\n<th>Module</th>\n<th>Infopad</th>\n<th>Row</th>\n<th>Column</th>\n<th>Slot</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>1</td>\n<td>Test</td>\n<td>Assignment</td>\n<td>assignment Rule</td>\n<td>Test report</td>\n<td>1</td>\n<td>count</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n5. Click Add Source to open the Add Source window.\n\nFigure 58: Add Source Page for New KPIs\n\na) Select an option from the Source Information list. Options include Process Templates or Infopads.\n\nb) Enter the name of the new Source in the Source box.\n\nc) If the Source information comes from a process template, then select options from the Process Template, Workstep, Event and Dataslot lists to further define the source.\nNote: The Dataslot drop-down list contains INTEGER and CHARACTER type dataslots only.\n\nd) If the Source information comes from an infopad, then specify the Application, Module, Infopad Name, Row, Column and Slot containing the updated value.\n\nNote: The Slot drop-down list does not contain the slots of type \"CHARACTER\".\n\ne) Click Save to save the new Source and go back to the Source List page to define additional sources. Depending upon whether the source information is specified as process template or infopad, the new source is added in the appropriate table in the Source List page.\n\nf) Click Next, to open the KPI List page where you can define KPIs for the new Balanced Scorecard.\n\n6. The KPI List page displays the list of KPI. You can select a perspective from the drop-down list beside Go, and click Go, to list KPIs of selected perspective only.\n\nFigure 59: Add KPI Page\n\n7. From the Perspective drop-down list, select the perspective to which the new KPI is assigned, and click Add KPI. The Add KPI window is opened.\n\na) The KPI Details tab displays the name of the selected balanced scorecard and perspective in read only mode.\n\nb) Enter the name of the KPI.\n\nNote: The KPI Name must be unique.\n\nc) Select a KPI type from the Type list. Options include:\n\n- Additive, which updates the current value by adding on any updated values.\n- Average, which updates the current value by averaging in any updated values.\n- Replace, which replaces the current value with the updated one.\nd) Enter values for each of the displayed parameters. Assign a weight -- weight values must be in the 0-1 range. The Current Value and Score are generally used for initialization purposes only. The Best Value and Worst Value are used in calculating the score. Unit is used for summary descriptions; longer descriptions are entered in Description. You can specify the target score between 0.0 and 10.0 for each KPI in the Target Score. The Balanced Scorecard Console displays the target score along with the actual score for each key performance indicator. It gives a visual indicator of achievements and help managers to track the progress.\n\ne) Select the Editable checkbox to enable users to modify the value or the Display checkbox to create a read-only value.\n\nf) Click Attach Source tab. This tab displays the list of available sources defined earlier and the list of sources attached to the KPI.\n\ng) Select one or more available sources from the Select Sources list and click Add to add them in the Attached Sources list. You can click Add All to add all available sources simultaneously. You may use Remove or Remove All to remove the sources from the Attached Sources list and put them back in the Select Sources list.\n\nh) Click Save to save the new KPI and go back to the KPI List page. The new KPI is listed in the table on this page.\n\n8. Click Finish to create the new Balanced Scorecard.\n\n9. A Confirmation message appears, indicating that you have successfully added a new Balanced Scorecard. Click OK to save it and return to the Balanced Scorecard List page.\n\nAfter you have designed and saved a new Balanced Scorecard, you (or someone like Business Process Server administrator, who has requisite access permissions) must install it as a new application from the Business Process Portal's Administration module for it to work properly.\n\nGenerating Rules in Balanced Scorecards\n\nBalanced Scorecard Designer automatically generates one rule file for each Balanced Scorecard. This rule file contains the following sections.\n\n• Initialization. This section creates an infopad containing the weights of the perspectives. The Perspective Weight infopad contains one row for each perspective in the scorecard. The lone slot in the cell provides the weight for that perspective, and each slot has an alarm that is triggered with the weight changes. This event triggers a rule that updates the overall score. Initialization creates a dynamic infopad for the overall score, with one row created for each month. The lone slot in the definition cell provides the score. Initialization also creates a dynamic infopad for each perspective, with one row for each month and one column for each KPI in that perspective. For more information, see Main Scorecard Group Rule.\n\n• Finalize. This section contains an entry for each of the infopads created that will destroy them when the rules are unloaded.\n\nThe rule file also contains the following rule groups:\n\n• Update Values. Updates the current values of the appropriate infopads. The Update Values rule vary depending on the KPI type and the number and type of data sources. If the KPI type is additive, then the Business Process Portal adds the value of the data source to the KPI’s current value slot. If the KPI type is averaging, then the Business Process Portal averages the value of the data source to the KPI’s current value slot. If the KPI type is replace, then the Business Process Portal action replaces the current value with the value of the data source.\n\n• Main Scorecard Group. Contains the escalation rules for calculation, rules that update the infopads when the collection process completes; and a rule that adds a row to all the dynamic infopads on the last day of a month and schedules the next month’s event. Cells in each infopad have an alarm that trigger a different update rule. Rules included in this group include:\n• **Perspective BestValue Rule**: Each perspective contains one best value rule, which is triggered when a BestValue slot has changed in a cell. It recalculates the score for the relevant KPI.\n\n• **Perspective WorstValue Rule**: Each perspective contains one worst value rule, which is triggered when a WorstValue slot has changed in a cell. It recalculates the score for the relevant KPI.\n\n• **Perspective CurrentValue Greater Than Rule**: Each perspective contains one CurrentValue Greater Than rule, which is triggered when a CurrentValue slot has changed, and the NegativeRange for that cell is ‘F’, meaning that the BestValue is greater than the WorstValue. The rule checks that the CurrentValue is less than BestValue; or it sets BestValue to the CurrentValue and checks that the CurrentValue is greater than WorstValue; or it sets WorstValue to the CurrentValue. It then generates an event that triggers a rule to recalculate the score.\n\n• **Perspective CurrentValue Less Than Rule**: Each perspective contains one CurrentValue Less Than rule, which is triggered when a CurrentValue slot has changed, and the NegativeRange for that cell is 'T', meaning that the BestValue is less than the WorstValue. The rule checks that the CurrentValue is greater than the BestValue; or it sets BestValue to the CurrentValue and checks that the CurrentValue is less than the WorstValue; or it sets WorstValue to the CurrentValue. It then generates an event that triggers a rule to recalculate the score.\n\n• **Perspective CurrentValue Update Rule**: Each perspective contains one CurrentValue Update rule, which is triggered by the event generated by the CurrentValue Greater than rule or the CurrentValue Less than rule. It then recalculates the score of the affected cell.\n\n• **Perspective RelativeWeight Rule**: Each perspective contains one RelativeWeight rule, which is triggered when the relative weight slot has changed in a cell and the affected cell is not in the last row of the infopad. It updates the sum of the weights in the last column. Then it issues an event for each KPI in the perspective that recalculates the score for each cell, triggering the CurrentValue Update rule.\n\n• **Perspective Score Rule**: Each perspective contains one Score rule, which is triggered when the score slot has changed in a cell. It then recalculates the perspective score.\n\n• **Perspective BSCard Rule**: Each perspective contains one BSCard rule, which is triggered when the Perspective score slot has changed. It issues an event that triggers a rule to recalculate the main overall score.\n\n• **Perspective BPServerUpdate Rule**: Each perspective contains one BPServerUpdate rule, which is triggered when the perspective subprocess W_COMPLETED event is sent. It then updates the CurrentValue for every KPI in the perspective.\n\n• **Perspective Weight BSCard Rule**: Each perspective contains one Perspective Weight BSCard rule, which is triggered when the weight for a perspective has been updated. It then triggers a rule to recalculate the main overall score.\n\n• **Overall UpdateMainBSC Rule**: Each perspective contains one UpdateMainBSC rule, which is triggered when perspective weights or scores change. It then updates the main overall score.\n\n• **AddRowsToScorecardInfopads Rule**: Each perspective contains one AddRowsToScorecardInfopads rule, which is triggered when the scheduled event is sent. For each of the dynamic infopads (i.e., each of the perspective infopads and the main scorecard infopad), a row is added and the values from the previous row are copied into the new row. Finally, an event is scheduled to trigger the rule on the last day of the next month.\n**Viewing and Modifying Existing Balanced Scorecards**\n\nIf you modify an existing Balanced Scorecard, to view the changes, then you (or Business Process Server administrator) must reinstall the modified Balanced Scorecard.\n\n**To access or modify existing Balanced Scorecard applications:**\n\n1. In the Management module, click Balanced Scorecard > Designer, to open the Balanced Scorecard List page, where all existing Balance Scorecards are listed.\n\n**Figure 60: Balanced Scorecard List Page**\n\nTo delete a Balanced Scorecard from those listed on the Balanced Scorecard List page, select a Balanced Scorecard from the list and click **Delete**.\n\nTo copy a Balanced Scorecard and save it as a new Balanced Scorecard, click **Save Balanced Scorecard Copy**... The copied balanced scorecard is not accessible from the Administration module because its rule file is not yet compiled. To compile it and make it accessible from the Administration module, you need to modify and save the copied balanced scorecard.\n\n2. Click the name of the balanced scorecard in the Balanced Scorecard column to view or modify the corresponding Balanced Scorecard, opening the Add Balanced Scorecard page. Change the name of the new Balanced Scorecard and/or its description.\n\nRefer **Figure 55** on page 106.\n\n3. Click **Next**, to open the Perspectives List page where you can modify perspectives of the Balanced Scorecard.\n\nRefer **Figure 56** on page 106.\n\nTo delete a Perspective from those listed on the Perspectives List page, select a Perspective from the list and click **Delete**. You can add new perspectives, and/or edit names/weights of the existing perspectives.\n\n4. Click **Next**, to open the Source List page where you can modify sources used by the KPIs of a Balanced Scorecard.\n\nTo delete a Source from those listed on the Source List page, select a Source from the list and click **Delete**. You can add new sources, and/or edit details of the existing sources.\n5. Click **Next**, to open the **KPI List** page where you can modify KPIs of the Balanced Scorecard.\n\n To delete a KPI from those listed on the **KPI List** page, select a KPI from the list and click **Delete**. You can add new KPIs, and/or edit details of the existing KPI.\n\n6. Click **Finish** to save the current scorecard.\nUsing the Infopad Manager\n\nAn infopad is a table, composed of elements called cells, that store such global data as application parameters (for example, a list of e-mail addresses of persons to notify) or rule parameters (for example, the critical threshold for a resource load). Each cell is a data structure made up of slots, or attributes, that in turn contain slotnames and values. The Infopad Manager enables you to edit the information provided in an infopad.\n\nFor details, see the following topics:\n\n- Modifying Infopad Values\n- Exporting Infopads\n\nModifying Infopad Values\n\nTo use Infopad Manager to modify infopad values:\n\n1. In the Management module, click Infopads, to view the Infopads page.\n2. Select the application from the Application drop-down list, then select the infopad you want to edit from the Infopad drop-down, and click Go. Names of the selected Application and Infopad are displayed below the selection bar.\n3. In the case of multidimensional infopads, an infopad cell is located in a specific row and column. Specify whether the infopad is to be sliced on row or column by selecting appropriate option. Depending on this selection, select the row/column from the drop-down list and click Go.\n\n After selecting a cell, the slotnames and their values within that cell appear below.\n4. Edit the values in the cell by changing the values in the text boxes in the Column.\n5. Click Save to save your changes. Business Process Portal saves your changes after your confirmation.\n\nTo reset the form and remove the information you just entered, click Reset.\n\n**Note:** For more information on infopads, see the \"Infopads\" chapter in the *BPM Events User's Guide*.\n\n### Exporting Infopads\n\nYou can export business metrics and Balanced Scorecards into different formats for creating reports and documentation.\n\n**To do so, follow these steps:**\n\n1. In the Management module, click Infopads, to view the Infopads page.\n2. Select the application from the Application drop-down list, then select the infopad you want to edit from the Infopad drop-down, and click Go.\n3. Select the format in which you want to export this data from the Export Type drop-down list. You can choose one of the HTML, XML or XLS formats. Click Export.\n\nBusiness Process Portal displays the infopads and their values in the specified format.\nPredefined Reports\n\nBusiness Process Server enables you to run a series of predefined reports that are based on selections you make from the following criteria:\n\n- **Report type.** In the submenu options under the Reports menu, choose from the Status Analysis, Time Analysis or Workload Analysis report types. The Time Analysis option, for example, enables you to run a report based on time factors.\n\n- **Analysis type.** In the Analysis for: drop-down list, select whether you want to execute a report based on Instance, Performer or Workstep.\n\n- **Application type.** In the Applications drop-down list, select All to run a report for all installed applications, or select a specific application.\n\n**Note:** You can select the **All** option in Application drop-down list in out of the box Jasper Report. In bpmportal.conf file, set bpmportal.report.allapplications parameter to false. The default value is true. If there is no installed application, then the **All** option is displayed irrespective of bpmportal.report.allapplications parameter configuration.\n\n- **Subcriteria** based on Report type.\n - When you select a Status Analysis report type, and analyze it for an Instance or Performer, a Status drop-down list is displayed that contains the following Status options: All, Active, Completed, Removed and Suspended, whereas when you analyze it for a Workstep, the Status drop-down list contains the following Status options: All, Active, Completed and Suspended. In the **Date** drop-down list, select a predefined interval (for example, All, Today, This Week, Last Month, etc.) or enter Start and End dates in the From: and To: boxes, respectively.\n \n - If you select a Time Analysis report type, then the Time Analysis drop-down list is displayed that contains the following options: Completion Time (time of actual or estimated completion),\nElapsed Time (the interval between start and current time—when a workstep is not yet completed and not overdue), Overdue Time (the amount of delay from the scheduled end time up to the current time for a workstep which is not yet completed and is overdue) and Estimated vs Elapsed Time. In the Date drop-down list, select a predefined interval (for example, All, Today, This Week, Last Month, etc.) or enter Start and End dates in the From: and To: boxes, respectively.\n\n- If you select a Workload Analysis report type, then a Workload Type drop-down list is displayed that contains the following options: Today’s Tasks (i.e., all tasks due the present day and overdue) or Due Today.\n\n**Note:** While filtering based on the date, only the starting date is considered.\n\nFor details, see the following topics:\n\n- Creating Status Analysis Reports\n- Creating Time Analysis Reports\n- Creating Workload Analysis reports\n\n## Creating Status Analysis Reports\n\nTo create a status analysis report that shows the total instances for each status (Active, Completed, Suspended, Removed) for the Assign_A_Task_V1 application.\n\n**Perform the following:**\n\n1. In the Management module, click **Reports > Status Analysis**, to view the **Status Analysis** page.\n2. Select:\n - **Instance** from the Analysis for: drop-down list.\n - **Assign_A_Task_V1** from the Applications list.\n - **All** from the Status list.\n - **None** from the Subprocess list.\n\nYou can analyze for Instance, Performer or Workstep.\n\n3. Specify the name of the creator in the **Creator** text box. Alternatively, click the Search User icon, and then select the creator from the displayed window.\n4. Select a predefined interval from the Date drop-down list (for example, All, Today, This Week, Last Month, etc.) or enter Start and End dates in the From: and To: boxes, respectively. Click the Select Date icon ( ) to facilitate entering a date.\n5. Click **Go**, and the report appears in the workspace.\n6. Select the preferred format from the Report Format drop-down list and click View to view the report in a specific format.\n\n7. Click Email... to open the Email Report dialog box. Enter information in the relevant boxes and select a format from the Report Format drop-down list.\n\n**Note**: If you select HTML, then the report mail is sent as an HTML formatted email. If your mail-tool supports mails in HTML format, then you can view the HTML report in your mail-tool. But if your mail-tool supports mails only in text format, then you cannot view the HTML report.\n\n8. Click Submit to email the report.\n\nTo reset the form and remove the information you just entered, click Reset. To cancel the action and exit the current dialog box, click Close.\n\n### Creating status of completed worksteps\n\nTo create a report that shows the status of all completed worksteps for the Assign_A_Task_V1 application.\nPerform the following:\n\n1. In the Management module, click Reports > Status Analysis, to view the Status Analysis page.\n\n2. Select:\n - Workstep from the Analysis for: drop-down list.\n - Assign_A_Task_V1 from the Applications list.\n - Completed from the Status list.\n - None from the Subprocess list.\n\n3. Specify the name of the performer in the Performer text box. Alternatively, click the Search User icon, and then select the performer from the displayed window.\n\n4. Select a predefined interval from the Date drop-down list (for example, Today, This Week, Last Month, etc.) or enter Start and End dates in the From: and To: boxes, respectively. Click the Select Date icon ( ) to facilitate entering a date.\n\n5. Click Go, and the report appears in the workspace.\n\nFigure 64: Status Analysis Report for Completed Worksteps for Assign_A_Task_V1\n\n6. Select the preferred format from the Report Format drop-down list and click View to view the report in a specific format.\n\n7. Click Email... to open the Email Report dialog box. Enter information in the relevant boxes and select a format from the Report Format drop-down list. Refer Figure 63 on page 117.\n\n8. Click Submit to email the report.\n\n To reset the form and remove the information you just entered, click Reset. To cancel the action and exit the current dialog box, click Close.\n\nCreating Time Analysis Reports\n\nTo create a time analysis report that shows the completion time for all instances of all applications:\n1. In the Management module, click Reports > Time Analysis, to view the Time Analysis page.\n\n2. Select:\n - **Instance** from the Analysis for: drop-down list.\n - **All** from the Applications list.\n - **Completion Time** from the Analysis Time list.\n\n3. Specify the name of the creator in the **Creator** text box. Alternatively, click the Search User icon, and then select the creator from the displayed window.\n\n4. Select a predefined interval from the **Date** drop-down list (for example, All, Today, This Week, Last Month, etc.) or enter Start and End dates in the From: and To: boxes, respectively. Click the **Select Date** icon to facilitate entering a date.\n\n5. Click **Go**, and the report appears in the workspace.\n\n**Figure 65: Time Analysis Report for Completion Time of Instances for All Application**\n\n6. Select the preferred format from the Report Format drop-down list and click **View** to view the report in a specific format.\n\n7. Click **Email...** to open the Email Report dialog box. Enter information in the relevant boxes and select a format from the Report Format drop-down list.\n\n Refer **Figure 63** on page 117.\n\n8. Click **Submit** to email the report.\n\n To reset the form and remove the information you just entered, click **Reset**. To cancel the action and exit the current dialog box, click **Close**.\n\n### Creating Elapsed time report\n\nTo create a report that shows the elapsed time (i.e., the interval between start and current time—when a workstep is not yet completed and not overdue) for all active worksteps of all applications.\n\n**Perform the following:**\n\n1. In the Management module, click Reports > Time Analysis, to view the Time Analysis page.\n\n2. Select:\n - **Workstep** from the Analysis for: drop-down list.\nTo create a workload analysis report that lists all instances of all applications that are overdue or due on the current day:\n\n1. In the Management module, click Reports > Workload Analysis, to view the Workload Analysis page.\n\n2. Select:\n - Instance from the Analysis for: drop-down list.\n - All from the Applications list.\n - Today’s Tasks from the Workload Type list.\n\n3. Specify the name of the performer in the Performer text box. Alternatively, click the Search User icon, and then select the performer from the displayed window.\n\n4. Select a predefined interval from the Date drop-down list (for example, All, Today, This Week, Last Month, etc.) or enter Start and End dates in the From: and To: boxes, respectively. Click the Select Date icon to facilitate entering a date.\n\n5. Click Go, and the report appears in the workspace.\n\n6. Select the preferred format from the Report Format drop-down list and click View to view the report in a specific format.\n\n7. Click Email... to open the Email Report dialog box. Enter information in the relevant boxes and select a format from the Report Format drop-down list. Refer Figure 63 on page 117.\n\n8. Click Submit to email the report.\n\n To reset the form and remove the information you just entered, click Reset. To cancel the action and exit the current dialog box, click Close.\n3. Specify the name of the creator in the **Creator** text box. Alternatively, click the Search User icon, and then select the creator from the displayed window.\n\n4. Click **Go**, and the report appears in the workspace.\n\n**Figure 67: Workload Analysis Report for All Due or Overdue Application Instances**\n\n\n\n5. Select the preferred format from the Report Format drop-down list and click **View** to view the report in a specific format.\n\n6. Click **Email...** to open the **Email Report** dialog box. Enter information in the relevant boxes and select a format from the Report Format drop-down list.\n\nRefer **Figure 63** on page 117.\n\n7. Click **Submit** to email the report.\n\nTo reset the form and remove the information you just entered, click **Reset**. To cancel the action and exit the current dialog box, click **Close**.\n\n---\n\n### Creating workload analysis report for a specific task\n\nTo create a workload analysis report that lists all performers that are responsible for tasks for the **Assign_A_Task_V1** application that are due on the current day:\n\n1. In the Management module, click **Reports > Workload Analysis**, to view the **Workload Analysis** page.\n\n2. Select:\n \n - **Performer** from the Analysis for: drop-down list.\n - **Approval** from the Applications list.\n - **Due Today** from the Workload Type list.\n\n3. Specify the name of the performer in the **Performer** text box. Alternatively, click the Search User icon, and then select the performer from the displayed window.\n\n4. Click **Go**, and the report appears in the workspace.\n5. Select the preferred format from the Report Format drop-down list and click View to view the report in a specific format.\n\n6. Click Email... to open the Email Report dialog box. Enter information in the relevant boxes and select a format from the Report Format drop-down list.\n\nRefer Figure 63 on page 117.\n\n7. Click Submit to email the report.\n\nTo reset the form and remove the information you just entered, click Reset. To cancel the action and exit the current dialog box, click Close.\nGlossary\n\nACL manager\nIn Business Process Server, Access Control List Manager provides a finer, more precise control over user access rights for resources and actions.\n\nActivity workstep\nIn Business Process, the basic unit of work; must be performed by one or more human performers (valid individual user, multiple users or user group).\n\nAdapter\nA Java class that integrates remote, third party classes and actions with Business Process. An adapter can automate certain functions and tasks performed by a remote server or other external systems.\n\nAdministration\nA module in Business Process Portal enabling the administrator to perform tasks such as installing/uninstalling applications, modifying configuration parameters controlling Business Process operations, and manage users, groups and access control. The Administration module is visible only to application users who have permissions to access it.\n\nApplication\nIn Business Process, an application is an installed, executable business process that automates a business flow.\n\nBalanced scorecard\nA management application in the Management module that measures performance by analyzing how an organization's business activities help it achieve its strategic goals. The Balanced Scorecard provides an analysis from a range of perspectives.\nBusiness Activity Management combines Business process management with strategic and analytical information on specific business performance indicators, providing real-time status information and identifying critical events to assist senior management in making informed business decisions.\n\nBPM Events\nA Business Process Server component that provides an open event-driven rule engine to formulate and enforce policies in business applications.\n\nBPM Webflow\nA Business Process Server component that enables users to develop customizable, sophisticated presentation flows for business processes, install them as Web applications, and execute them on their Web browsers.\n\nBPEL\nBPEL (Business Process Execution Language) for Web services is an XML-based language designed to enable task-sharing for a distributed computing or grid computing environment - including across multiple organizations - using a combination of Web services.\n\nBPMN\nBPMN (Business Process Modelling Notation) provides businesses with the capability of defining and understanding their internal and external business procedures through a Business Process Diagram giving organizations the ability to communicate these procedures in a standard manner.\n\nBP Server\nA Business Process Server component that provides a flexible, lightweight, scalable workflow process engine for intranets, extranets, and the Internet.\n\nBusiness calendar\nA Business Process Server feature that accurately calculates the Due Date of tasks, and provides support for multiple business calendars across different time zones.\n\nBusiness flow\nThe logical sequence of process activities, related to one another by a triggering activity, to achieve an outcome. It represents a business process that begins with a commitment and ends with the termination of that commitment. In Business Process Server, business flow includes Workflow (the flow of all human-performed activities), integration flow (the flow of activities performed by systems) and presentation flow (from a user’s viewpoint, the flow of data from one Web page to the next).\n\nBusiness logic\nThe control flow and information flow among worksteps that define a business process.\n\nBusiness object\nA representation of an activity in the business domain, including its name, definition, attributes, behavior, relationships and constraints.\n\nBusiness process\nA process involving multiple worksteps in the form of operations, interactions and notifications performed by a user, group of users, an external adapter, or a script.\nBusiness Process Server application\nAn application is an implementation of a business process. It can contain one or more process templates, performers, adapters, customized forms or rules. An application can be published, installed and run on BP Servers. In Business Process Server, an application is an installed, executable business process that automates a Workflow.\n\nBusiness Process Server Web services\nA Business Process Server component that allows application developers to; a) publish their applications as Web services, and b) find and convert other available Web services on the Internet into Business Process Server applications.\n\nBusiness Process Portal\nA Business Process Server component that offers users, managers, administrators and developers a unified, customizable portal for single sign-on access to all Business Process Server functionalities to which they are granted permission.\n\nBusiness process management\nThe concept of guiding work activities through a multi-step business process in order to improve performance and reduce costs within and across functional business units.\n\nBusiness Process Modeler\nA stand-alone component that enables users to design templates for basic business processes.\n\nBusiness rule\nA combination of elements, including validation edits, logon verifications, database lookups, policies and transformations, that represent an enterprise’s way of doing business.\n\nControl flow\nThe sequences of worksteps and workstep conditions, as defined in a process template in Progress Developer Studio for OpenEdge or Business Process Modeler.\n\nDashboard\nA Business Process Server feature that provides a graphic overview of the status of several business processes on a single Web page, enabling users to monitor the progress of each process. Users can view business processes across all applications or for a selected application.\n\nDataslot\nA data placeholder that persists through the entire process and defines the information flow of the business process. Dataslots are associated with processes, where they can add information into (Input type) or out of (Output type) worksteps, and appear as editable or read-only fields on a user's interface.\n\nExpression editor\nA Business Process Server tool that enables users to define complex conditional expressions within a Decision gateway to support their business requirements.\n\nGroup\nIn Business Process Server, an entity that has as members valid users or other groups who perform related work and have authorized access to specific components.\nHeatmap\nA Business Process Server feature that provides a convenient, graphical tool for managers to visually locate the bottlenecks in the process execution. It helps managers to get an overview of the status of the currently active instances, identify suspended instances, and analyze the history of the completed instances.\n\nHome\nA module in Business Process Portal through which users interact with Business Process Server. Using the Home module, users complete entries to various tasks and applications, update profile, set preferences, and link to the support infrastructure required to achieve these tasks. The Home module is the primary interface for application users.\n\nInfopad\nIn Business Process Server, a data structure used to capture business metrics, typically displayed as a table with one or two dimensions.\n\nInstance\nAn individual object within a specific class. In Business Process Server, a self-contained unit that is created each time you use a process template to run a Business Process Server application.\n\nKPI\nKey Performance Indicator, used in the Balanced Scorecard system, that provides the data translating enterprise goals into a set of measurable objectives.\n\nManaged Adapter\nIn Business Process Server, a Managed Adapter is an implementation of an adapter interface that facilitates data exchange between Business Process Server processes and external applications.\n\nManagement\nA module in Business Process Portal enabling the managers to query, report, and control processes and resources for application users. The Management module is visible only to application users who have permissions to access it.\n\nMigration\nThe process of moving from the use of one operating environment to another operating environment that is typically seen as improvement. Migration can involve moving to new hardware, new software, or both. It may involve a new application, another type of database, or a redesigned network. Migration is also used to refer simply to the process of moving data from one storage device to another. Business Process Server supports data migration as well as application migration.\n\nPerformer\nAn entity that executes a workstep. Depending on the workstep type, the performer can be a human user, a group of users, an adapter or other external performer, or a script.\n\nPresentation flow\nThe flow of information and user input from one interface to the next. Typically related to a single Activity workstep in the process and generated in a BPM Webflow environment.\n\nProcess engine\nOrchestrates the execution of business processes and also coordinates conversations among process engines based on public processes, which forms the backbone of global business collaboration.\nProcess refresh\nA Business Process Server feature for replacing the installed process without versioning, facilitating the running process instances to refresh and seamlessly adapt to the new Workflow.\n\nProcess template\nIn Business Process Server, a model of business flow that includes worksteps, connectors and dataslots. After users publish and install it as an application in Business Process Server folder structure, they can use the application to create process instances.\n\nProgress Developer Studio for OpenEdge\nAn Integrated Development Environment for Business Process Server that enables application users to develop and publish a Business Process Server application without leaving the development environment.\n\nRole\nThe actions and activities assigned to a valid application user who is a member of a group. In Business Process Server, only members of a group can be assigned a role. A role indicates the relationships of the user in a group context.\n\nRollback\nIn Business Process Server, a feature that restarts the Workflow from a workstep previously selected as the rollback point in the process, performed automatically in the event of a failure.\n\nRule wizard\nAn interactive utility that enables application users to quickly develop rules that can be applied to a business process.\n\nSwim lanes\nUsed in Workflow diagrams to organize complex processes across functional boundaries. For example, seen as horizontal lines on a process map, swim lanes can be used to place individual task steps into different categories that depend on task ownership.\n\nTask\nIn Business Process Server, a performer is assigned one or more work items that the performer sees as tasks. There are two types of tasks: Assigned, which are assigned specifically to you; and Available, which are available to be performed by you or other members of your user group.\n\nUser\nIn Business Process Server, a valid human performer with authorized access to specific modules.\n\nWorkflow\nThe logical sequence of activities performed by human performers. Workflow includes the tasks, procedural steps, organizations or people involved, required input and output information, and tools needed for each activity in a business process."}}},{"rowIdx":97,"cells":{"id":{"kind":"string","value":"5d91054894b3e0ae1537b7c25f7dc5edb09160b2"},"text":{"kind":"string","value":"Table of Contents\n\n1. Setup a development system ................................................................. 1\n 1.1. Operating System/Environment ......................................................... 1\n 1.2. Installation ......................................................................................... 1\n 1.3. Tooling ............................................................................................... 3\n 1.4. Useful links ....................................................................................... 3\n 1.4.1. General ....................................................................................... 3\n 1.4.2. Installation/Setup ................................................................. 3\n2. Minion development ............................................................................. 4\n 2.1. Introduction ....................................................................................... 4\n 2.2. Container ........................................................................................... 4\n 2.2.1. Clean Start ............................................................................... 4\n 2.2.2. Karaf Extender ....................................................................... 4\n 2.3. Guidelines ......................................................................................... 5\n 2.3.1. Security .................................................................................... 5\n 2.4. Testing ............................................................................................... 5\n 2.4.1. Local Testing ............................................................................ 5\n 2.4.2. System Tests ........................................................................... 5\n3. Topology ................................................................................................ 6\n 3.1. Info Panel Items ............................................................................... 6\n 3.1.1. Programmatic ............................................................................ 6\n 3.1.2. Scriptable .................................................................................. 7\n 3.2. GraphML ........................................................................................... 11\n 3.2.1. Create/Update/Delete GraphML Topology ................................ 12\n 3.2.2. Supported Attributes ............................................................... 13\n 3.2.3. Focus Strategies ................................................................. 14\n 3.2.4. Icons ......................................................................................... 15\n 3.2.5. Vertex Status Provider ....................................................... 15\n 3.2.6. Edge Status Provider ............................................................. 15\n 3.2.7. Layers ....................................................................................... 16\n 3.2.8. Breadcrumbs ............................................................................ 19\n 3.3. Topologies Updates .......................................................................... 22\n 3.3.1. OnmsTopologyUpdater ............................................................. 22\n 3.3.2. OnmsTopologyRef ................................................................. 23\n 3.3.3. OnmsTopologyMessage .......................................................... 23\n 3.3.4. OnmsTopologyProtocol ......................................................... 23\n 3.3.5. TopologyMessageStatus ......................................................... 23\n 3.3.6. OnmsTopology ................................................................. 24\n 3.3.7. OnmsTopologyVertex .............................................................. 24\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>3.3.8. OnmsTopologyEdge</td>\n<td>24</td>\n</tr>\n<tr>\n<td>3.3.9. OnmsTopologyPort</td>\n<td>24</td>\n</tr>\n<tr>\n<td>3.3.10. OnmsTopologyConsumer</td>\n<td>24</td>\n</tr>\n<tr>\n<td>4. Graph Service API</td>\n<td>25</td>\n</tr>\n<tr>\n<td>4.1. Terminology</td>\n<td>25</td>\n</tr>\n<tr>\n<td>4.2. Graph Model</td>\n<td>25</td>\n</tr>\n<tr>\n<td>4.2.1. Generic Graph Model</td>\n<td>25</td>\n</tr>\n<tr>\n<td>4.2.2. Domain Graph Model</td>\n<td>26</td>\n</tr>\n<tr>\n<td>4.2.3. Immutability</td>\n<td>26</td>\n</tr>\n<tr>\n<td>4.3. Providers</td>\n<td>26</td>\n</tr>\n<tr>\n<td>4.3.1. Meta Information</td>\n<td>26</td>\n</tr>\n<tr>\n<td>4.4. Cache</td>\n<td>27</td>\n</tr>\n<tr>\n<td>4.5. Search</td>\n<td>27</td>\n</tr>\n<tr>\n<td>4.6. Focus / Semantic Zoom Level / View</td>\n<td>27</td>\n</tr>\n<tr>\n<td>4.7. Listening for Changes</td>\n<td>28</td>\n</tr>\n<tr>\n<td>4.8. Persistence</td>\n<td>28</td>\n</tr>\n<tr>\n<td>4.9. Enrichment</td>\n<td>28</td>\n</tr>\n<tr>\n<td>4.9.1. Build in Enrichment</td>\n<td>28</td>\n</tr>\n<tr>\n<td>4.10. ReST API</td>\n<td>28</td>\n</tr>\n<tr>\n<td>4.11. Limitations</td>\n<td>29</td>\n</tr>\n<tr>\n<td>5. CORS Support</td>\n<td>30</td>\n</tr>\n<tr>\n<td>5.1. Why do I need CORS support?</td>\n<td>30</td>\n</tr>\n<tr>\n<td>5.2. How can I enable CORS support?</td>\n<td>30</td>\n</tr>\n<tr>\n<td>5.3. How can I configure CORS support?</td>\n<td>30</td>\n</tr>\n<tr>\n<td>6. ReST API</td>\n<td>31</td>\n</tr>\n<tr>\n<td>6.1. ReST URL</td>\n<td>31</td>\n</tr>\n<tr>\n<td>6.2. Authentication</td>\n<td>31</td>\n</tr>\n<tr>\n<td>6.3. Data format</td>\n<td>31</td>\n</tr>\n<tr>\n<td>6.4. Standard Parameters</td>\n<td>31</td>\n</tr>\n<tr>\n<td>6.5. Standard filter examples</td>\n<td>32</td>\n</tr>\n<tr>\n<td>6.6. HTTP Return Codes</td>\n<td>33</td>\n</tr>\n<tr>\n<td>6.7. Identifying Resources</td>\n<td>33</td>\n</tr>\n<tr>\n<td>6.8. Expose ReST services via OSGi</td>\n<td>34</td>\n</tr>\n<tr>\n<td>6.8.1. Define a ReST interface</td>\n<td>34</td>\n</tr>\n<tr>\n<td>6.8.2. Implement a ReST interface</td>\n<td>35</td>\n</tr>\n<tr>\n<td>6.8.3. Export the ReST service</td>\n<td>35</td>\n</tr>\n<tr>\n<td>6.9. Currently Implemented Interfaces</td>\n<td>36</td>\n</tr>\n<tr>\n<td>6.9.1. Acknowledgements</td>\n<td>36</td>\n</tr>\n<tr>\n<td>6.9.2. Alarm Statistics</td>\n<td>37</td>\n</tr>\n<tr>\n<td>6.9.3. Alarms</td>\n<td>37</td>\n</tr>\n<tr>\n<td>6.9.4. Alarm History</td>\n<td>39</td>\n</tr>\n</tbody>\n</table>\n7.2.1. Conventions for text formatting ........................................................................ 121\n7.2.2. Gotchas ........................................................................................................ 121\n7.3. Headings and document structure................................................................. 122\n7.4. Links ................................................................................................................ 122\n7.5. Admonitions and useful notes....................................................................... 123\n7.6. Attributes ....................................................................................................... 124\n7.7. Comments....................................................................................................... 125\n7.8. Tables .............................................................................................................. 125\n7.9. Include images ............................................................................................... 126\n7.10. Code Snippets ............................................................................................... 128\n 7.10.1. Explicitly defined in the document ......................................................... 128\n 7.10.2. Included from an example file ............................................................... 129\n 7.10.3. Include parts of a file ............................................................................... 129\n7.11. Cheat sheets and additional hints ............................................................. 130\n7.12. Migrating content from project wiki ............................................................ 131\n8. AMQP Integration ............................................................................................. 133\n 8.1. Event Forwarder ............................................................................................ 133\n 8.1.1. Setup ...................................................................................................... 134\n 8.1.2. Debugging ............................................................................................. 134\n 8.2. Event Receiver .............................................................................................. 134\n 8.2.1. Setup ...................................................................................................... 135\n 8.2.2. Debugging ............................................................................................. 135\n 8.3. Alarm Northbounder .................................................................................... 135\n 8.3.1. Setup ...................................................................................................... 136\n 8.3.2. Debugging ............................................................................................. 136\n 8.4. Custom Processors ....................................................................................... 136\n9. Design and Styleguidelines .............................................................................. 138\nChapter 1. Setup a development system\n\nThis guide describes the requirements and how to get started with the development of the OpenNMS project.\n\n1.1. Operating System/Environment\n\nTo build/compile OpenNMS requires running a *nix system. You do not need to run it physically, a virtual machine is sufficient. We recommend one of the following:\n\n- Linux Mint with Cinnamon Desktop environment\n- Ubuntu Desktop\n- Mac OS X\n\nThis documentation describes a Debian-based desktop environment.\n\n1.2. Installation\n\nFollow these instructions to set up your environment. They may vary depending on your operating system:\n# add OpenNMS as repository to install icmp and such\necho \"deb http://debian.opennms.org stable main\" >\n/etc/apt/sources.list.d/opennms.list\necho \"deb-src http://debian.opennms.org stable main\" >>\n/etc/apt/sources.list.d/opennms.list\n# Add pgp key\nwget -O - https://debian.opennms.org/OPENNMS-GPG-KEY | apt-key add -\n\n# overall update\napt-get update\n\n# install stuff\napt-get install -y software-properties-common\napt-get install -y git-core\napt-get install -y nsis\n\n# install Oracle Java 8 JDK\n# this setup is based on: http://www.webupd8.org/2014/03/how-to-install-oracle-java-8-\nin-debian.html\nadd-apt-repository -y ppa:webupd8team/java\napt-get update\napt-get install -y oracle-java8-installer\napt-get install -y oracle-java8-set-default\n\n# install and configure PostgreSQL\napt-get install -y postgresql\necho \"local all postgres peer\" >\n/etc/postgresql/9.3/main/pg_hba.conf\necho \"local all all peer\" >>\n/etc/postgresql/9.3/main/pg_hba.conf\necho \"host all all 127.0.0.1/32 trust\" >>\n/etc/postgresql/9.3/main/pg_hba.conf\necho \"host all all ::1/128 trust\" >>\n/etc/postgresql/9.3/main/pg_hba.conf\n# restart postgres to use new configs\n/etc/init.d/postgresql restart\n\n# install OpenNMS basic dependencies\napt-get install -y maven\napt-get install -y jicmp jicmp6\napt-get install -y jrrd\n\n# clone opennms\nmkdir -p ~/dev/opennms\ngit clone https://github.com/OpenNMS/opennms.git ~/dev/opennms\n\nAfter this you should be able to build OpenNMS:\nFor more information on how to build OpenNMS from source, check this wiki Install from Source.\n\nAfter successfully building OpenNMS, please follow the wiki Running OpenNMS.\n\n1.3. Tooling\n\nWe recommend the following toolset:\n\n- IDE: IntelliJ IDEA Ultimate\n- DB-Tool: DBeaver or Postgres Admin - pgAdmin\n- Graphing: yEd\n- Other: atom.io\n\n1.4. Useful links\n\n1.4.1. General\n\n- source code hosted on GitHub\n- Our Wiki, especially the start page. It points you in the right direction.\n- Our issue/bug tracker\n- Vagrant box to set up a virtual box to build OpenNMS\n- vagrant box to set up a virtual box to run OpenNMS\n\n1.4.2. Installation/Setup\n\n- http://www.opennms.eu/docs/opennms-community-welcome-guide/0.0.5-SNAPSHOT/\n- http://www.opennms.org/wiki/Eclipse_and_OpenNMS\n- http://www.opennms.org/wiki/IDEA_and_OpenNMS\nChapter 2. Minion development\n\n2.1. Introduction\n\nThis guide is intended to help developers get started with writing Minion related features. It is not intended to be an exhaustive overview of the Minion architecture or feature set.\n\n2.2. Container\n\nThis section details the customizations we make to the standard Karaf distribution for the Minion container.\n\n2.2.1. Clean Start\n\nWe clear the cache on every start by setting karaf.clean.cache = true in order to ensure that only the features listed in the featuresBoot (or installed by the karaf-extender) are installed.\n\n2.2.2. Karaf Extender\n\nThe Karaf Extender was developed to make it easier to manage and extend the container using existing packaging tools. It allows packages to register Maven Repositories, Karaf Feature Repositories and Karaf Features to Boot by overlaying additional files, avoiding modifying any of the existing files.\n\nHere’s an overview, used for reference, of the relevant directories that are (currently) present on a default install of the opennms-minion package:\n\n```\n├── .m2\n│ ├── etc\n│ │ └── featuresBoot.d\n│ │ └── custom.boot\n│ └── repositories\n│ │ └── core\n│ │ └── features.uris\n│ │ └── features.boot\n│ └── default\n│ └── features.uris\n│ └── features.boot\n└── system\n```\n\nWhen the karaf-extender feature is installed it will:\n\n1. Find all of the folders listed under $karaf.home/repositories that do not start with a '.' and sort these by name.\n2. Gather the list of Karaf Feature Repository URIs from the features.uris files in the repositories.\n3. Gather the list of Karaf Feature Names from the features.boot files in the repositories.\n4. Gather the list of Karaf Feature Names from the files under $karaf.etc/featuresBoot.d that do not start with a '.' and sort these by name.\n\n5. Register the Maven Repositories by updating the org.ops4j.pax.url.mvn.repositories key for the PID org.ops4j.pax.url.mvn.\n\n6. Wait up to 30 seconds until all of the Karaf Feature URIs are resolvable (the Maven Repositories may take a few moments to update after updating the configuration.)\n\n7. Install the Karaf Feature Repository URIs.\n\n8. Install the Karaf Features.\n\n- Features listed in the features.boot files of the Maven Repositories will take precedence over those listed in featuresBoot.d.\n\n- Any existing repository registered in org.ops4j.pax.url.mvn.repositories will be overwritten.\n\n### 2.3. Guidelines\n\nThis sections describes a series of guidelines and best practices when developing Minion modules:\n\n#### 2.3.1. Security\n\n1. Don’t store any credentials on disk, use the SecureCredentialVault instead.\n\n### 2.4. Testing\n\nThis sections describes how developers can test features on the Minion container.\n\n#### 2.4.1. Local Testing\n\nYou can compile, assemble, and spawn an interactive shell on the Minion container using:\n\n**Assemble and run the container in place**\n\n```bash\ncd features/minion && ./runInPlace.sh\n```\n\n#### 2.4.2. System Tests\n\nThe runtime environment of the Minion container and features differs greatly from those provided by the unit and integration tests. For this reason, it is important to perform automated end-to-end testing of the features.\n\nThe system tests provide a framework which allows developers to instantiate a complete Docker-based Minion system using a single JUnit rule.\n\nFor further details, see the minion-system-tests project on Github.\nChapter 3. Topology\n\n3.1. Info Panel Items\n\nThis section is under development. All provided examples or code snippet may not fully work. However they are conceptionally correct and should point in the right direction.\n\nEach element in the Info Panel is defined by an InfoPanelItem object.\n\nAll available InfoPanelItem objects are sorted by the order. This allows to arrange the items in a custom order. After the elements are ordered, they are put below the SearchBox and the Vertices in Focus list.\n\n3.1.1. Programmatic\n\nIt is possible to add items to the Info Panel in the Topology UI by simply implementing the interface InfoPanelItemProvider and expose its implementation via OSGi.\n\nSimple Java InfoPanelItemProvider\n\n```java\npublic class ExampleInfoPanelItemProvider implements InfoPanelItemProvider {\n @Override\n public Collection<? extends InfoPanelItem> getContributions(GraphContainer container) {\n return Collections.singleton(\n new DefaultInfoPanelItem() ①\n .withTitle(\"Static information\") ②\n .withOrder(0) ③\n .withComponent(\n new com.vaadin.v7.ui.Label(\"I am a static component\") ④\n )\n );\n }\n}\n```\n\n① The default implementation of InfoPanelItem. You may use InfoPanelItem instead if the default implementation is not sufficient.\n\n② The title of the InfoPanelItem. It is shown above the component.\n\n③ The order.\n\n④ A Vaadin component which actually describes the custom component.\n\nIn order to show information based on a selected vertex or edge, one must inherit the classes EdgeInfoPanelItemProvider or VertexInfoPanelItemProvider. The following example shows a custom EdgeInfoPanelItemProvider.\nSimple Java EdgeInfoPanelItemProvider\n\n```java\npublic class ExampleEdgeInfoPanelItemProvider extends EdgeInfoPanelItemProvider {\n\n @Override\n protected boolean contributeTo(EdgeRef ref, GraphContainer graphContainer) { ①\n return \"custom-namespace\".equals(ref.getNamespace()); // only show if of certain namespace\n }\n\n @Override\n protected InfoPanelItem createInfoPanelItem(EdgeRef ref, GraphContainer graphContainer) { ②\n return new DefaultInfoPanelItem()\n .withTitle(ref.getLabel() + \" Info\")\n .withOrder(0)\n .withComponent(\n new com.vaadin.v7.ui.Label(\"Id: \" + ref.getId() + \",\n Namespace: \" + ref.getNamespace())\n );\n }\n}\n```\n\n① Is invoked if one and only one edge is selected. It determines if the current edge should provide the InfoPanelItem created by createInfoPanelItem.\n\n② Is invoked if one and only one edge is selected. It creates the InfoPanelItem to show for the selected edge.\n\nImplementing the provided interfaces/classes, is not enough to have it show up. It must also be exposed via a blueprint.xml to the OSGi service registry. The following blueprint.xml snippet describes how to expose any custom InfoPanelItemProvider implementation to the OSGi service registry and have the Topology UI pick it up.\n\n**blueprint.xml snippet**\n\n```xml\n<service interface=\"org.opennms.features.topology.api.info.InfoPanelItemProvider\"> ①\n <bean class=\"ExampleInfoPanelItemProvider\" /> ②\n</service>\n```\n\n① The service definition must always point to InfoPanelItemProvider.\n\n② The bean implementing the defined interface.\n\n### 3.1.2. Scriptable\n\nBy simply dropping JinJava templates (with file extension .html) to $OPENNMS_HOME/etc/infopanel a more scriptable approach is available. For more information on JinJava refer to https://github.com/HubSpot/jinjava.\n\nThe following example describes a very simple JinJava template which is always visible.\n**Static scriptable template**\n\n{% set visible = true %} ①\n{% set title = \"Static information\" %} ②\n{% set order = -700 %} ③\n\nThis information is always visible ④\n\n① Makes this always visible \n② Defines the title \n③ Each info panel item is ordered at the end. Making it -700 makes it very likely to pin this to the top of the info panel item.\n\nA template showing custom information may look as following:\n\n**Vertex specific template**\n\n{% set visible = vertex != null && vertex.namespace == \"custom\" && vertex.customProperty is defined %} ①\n{% set title = \"Custom Information\" %}\n\n<table width=\"100%\" border=\"0\">\n <tr>\n <td colspan=\"3\">This information is only visible if a vertex with namespace \"custom\" is selected</td>\n </tr>\n <tr>\n <td align=\"right\" width=\"80\">Custom Property</td>\n <td width=\"14\"></td>\n <td align=\"left\">{{ vertex.customProperty }}</td>\n </tr>\n</table>\n\n① This template is only shown if a vertex is selected and the selected namespace is \"custom\".\n\nIt is also possible to show performance data.\n\n**Including resource graphs**\n\nOne can include resource graphs into the info panel by using the following HTML element:\n\n```html\n<div class=\"graph-container\" data-resource-id=\"RESOURCE_ID\" data-graph-name=\"GRAPH_NAME\"></div>\n```\n\nOptional attributes data-graph-start and data-graph-end can be used to specify the displayed time range in seconds since epoch.\n\n**Measurements API template (memory usage)**\n{% set visible = node != null && node.sysObjectId == \".1.3.6.1.4.1.8072.3.2.10\" %}\n{% set order = 110 %}\n\n{% set title = \"System Memory\" %}\n\n{% set resourceId = \"node[\" + node.id + \"]\\.nodeSnmp[\" %}\n\n{% set attributeId = \"hrSystemUptime\" %}\n\n{% set total = measurements.getLastValue(resourceId, \"memTotalReal\")/1000/1024 %}\n{% set avail = measurements.getLastValue(resourceId, \"memAvailReal\")/1000/1024 %}\n\n<table border=\"0\" width=\"100%\">\n <tr>\n <td width=\"80\" align=\"right\" valign=\"top\">Total</td>\n <td width=\"14\">{{ total|round(2) }} GB(s)\n </td>\n </tr>\n <tr>\n <td width=\"80\" align=\"right\" valign=\"top\">Used</td>\n <td width=\"14\">{{ (total-avail)|round(2) }} GB(s)\n </td>\n </tr>\n <tr>\n <td width=\"80\" align=\"right\" valign=\"top\">Available</td>\n <td width=\"14\">{{ avail|round(2) }} GB(s)\n </td>\n </tr>\n <tr>\n <td width=\"80\" align=\"right\" valign=\"top\">Usage</td>\n <td width=\"14\">{{ ((total-avail)/total*100)|round(2) }}%\n </td>\n </tr>\n</table>\nMeasurements API template (uptime)\n\n{% set visible = node != null & node.sysObjectID == \".1.3.6.1.4.1.8072.3.2.10\" %}\n{% set order = 100 %}\n\n{% set title = \"System Uptime\" %}\n\n{% set resourceId = \"node[\" + node.id + \"]\\.nodeSnmp[]\" %}\n\n{% set attributeId = \"hrSystemUptime\" %}\n\n<table border=\"0\" width=\"100%\">\n <tr>\n <td width=\"80\" align=\"right\" valign=\"top\">getLastValue()</td>\n <td width=\"14\"></td>\n <td align=\"left\" valign=\"top\">\n {% Querying the last value via the getLastValue() method: %}\n </td>\n </tr>\n <tr>\n <td width=\"80\" align=\"right\" valign=\"top\">query()</td>\n <td width=\"14\"></td>\n <td align=\"left\" valign=\"top\">\n {% Querying the last value via the query() method. A custom function 'currentTimeMillis()' in the namespace 'System' is used to get the timestamps for the query: %}\n {% set end = System:currentTimeMillis() %}\n {% set start = end - (15 * 60 * 1000) %}\n {% set values = measurements.query(resourceId, attributeId, start, end, 300000, \"AVERAGE\") %}\n {% for value in values|reverse %}\n {% if value != \"NaN\" %}\n {% set last == \"NaN\" %}\n {{ (value/100.0/60.0/60.0/24.0)|round(2) }} day(s)\n {% set last = value %}\n {% endif %}\n {% endfor %}\n </td>\n </tr>\n</table>\n### 3.2. GraphML\n\nIn OpenNMS Horizon the `GraphMLTopoloyProvider` uses GraphML formatted files to visualize graphs.\n\nGraphML is a comprehensive and easy-to-use file format for graphs. It consists of a language core to describe the structural properties of a graph and a flexible extension mechanism to add application-specific data. [...] Unlike many other file formats for graphs, GraphML does not use a custom syntax. Instead, it is based on XML and hence ideally suited as a common denominator for all kinds of services generating, archiving, or processing graphs.\n\n— http://graphml.graphdrawing.org\n\nOpenNMS Horizon does not support the full feature set of GraphML. The following features are not supported: Nested graphs, Hyperedges, Ports and Extensions. For more information about GraphML refer to the [Official Documentation](#).\n\nA basic graph definition using GraphML usually consists of the following GraphML elements:\n\n- Graph element to describe the graph\n- Key elements to define custom properties, each element in the GraphML document can define as data elements\n- Node and Edge elements\n- Data elements to define custom properties, which OpenNMS Horizon will then interpret.\n\nA very minimalistic example is given below:\n<graphml xmlns=\"http://graphml.graphdrawing.org/xmlns\"\n xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n xsi:schemaLocation=\"http://graphml.graphdrawing.org/xmlns http://graphml.graphdrawing.org/xmlns/1.0/graphml.xsd\">\n <!-- key section -->\n <key id=\"label\" for=\"all\" attr.name=\"label\" attr.type=\"string\"></key>\n <key id=\"namespace\" for=\"graph\" attr.name=\"namespace\" attr.type=\"string\"></key>\n\n <!-- shows up in the menu -->\n <data key=\"label\">Minimalistic GraphML Topology Provider</data> ①\n <graph id=\"minimalistic\"> ②\n <data key=\"namespace\">minimalistic</data> ③\n <node id=\"node1\"/> ④\n <node id=\"node2\"/>\n <node id=\"node3\"/>\n <node id=\"node4\"/>\n </graph>\n</graphml>\n\n① The optional label of the menu entry.\n② The graph definition.\n③ Each graph must have a namespace, otherwise OpenNMS Horizon refuses to load the graph.\n④ Node definitions.\n\n3.2.1. Create/Update/Delete GraphML Topology\n\nIn order to create a GraphML Topology, a valid GraphML xml file must exist. Afterwards this is send to the OpenNMS Horizon REST API to create it:\n\n```\ncurl -X POST -H \"Content-Type: application/xml\" -u admin:admin -d@graph.xml\n'http://localhost:8980/opennms/rest/graphml/topology-name'\n```\n\nThe topology-name is a unique identifier for the Topology. If a label property is defined for the Graphml element this is used to be displayed in the Topology UI, otherwise the topology-name defined here is used as a fallback.\n\nTo delete an already existing Topology a HTTP DELETE request must be send:\n\n```\ncurl -X DELETE -u admin:admin 'http://localhost:8980/opennms/rest/graphml/topology-name'\n```\n\nThere is no PUT method available. In order to update an existing GraphML Topology one must first delete and afterwards re-create it.\nEven if the HTTP Request was successful, it does not mean, that the Topology is actually loaded properly. The HTTP Request states that the Graph was successfully received, persisted and is in a valid GraphML format. However, the underlying GraphMLTopologyProvider may perform additional checks or encounters problems while parsing the file. If the Topology does not show up, the karaf.log should be checked for any clues what went wrong. In addition it may take a while before the Topology is actually selectable from the Topology UI.\n\n### 3.2.2. Supported Attributes\n\nA various set of GraphML attributes are supported and interpreted by OpenNMS Horizon while reading the GraphML file. The following table explains the supported attributes and for which GraphML elements they may be used.\n\nThe type of the GraphML-Attribute can be either boolean, int, long, float, double, or string. These types are defined like the corresponding types in the Java™-Programming language.\n\n— [http://graphml.graphdrawing.org/primer/graphml-primer.html#Attributes](http://graphml.graphdrawing.org/primer/graphml-primer.html#Attributes)\n\n**Table 1. Supported GraphML Attributes**\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Required</th>\n<th>For element</th>\n<th>Type</th>\n<th>Default</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>namespace</td>\n<td>yes</td>\n<td>Graph</td>\n<td>string</td>\n<td>-</td>\n<td>The namespace must be unique overall existing Topologies.</td>\n</tr>\n<tr>\n<td>description</td>\n<td>no</td>\n<td>Graph</td>\n<td>string</td>\n<td>-</td>\n<td>A description, which is shown in the Info Panel.</td>\n</tr>\n<tr>\n<td>preferred-layout</td>\n<td>no</td>\n<td>Graph</td>\n<td>string</td>\n<td>D3</td>\n<td>Defines a preferred layout.</td>\n</tr>\n<tr>\n<td>focus-strategy</td>\n<td>no</td>\n<td>Graph</td>\n<td>string</td>\n<td>FIRST</td>\n<td>Defines a focus strategy. See <a href=\"#\">Focus Strategies</a> for more information.</td>\n</tr>\n<tr>\n<td>focus-ids</td>\n<td>no</td>\n<td>Graph</td>\n<td>string</td>\n<td>-</td>\n<td>Refers to nodes ids in the graph. This is required if focus-strategy is SPECIFIC. If multiple ids should be add to focus, they are separated by ,. Example: node1,node2</td>\n</tr>\n<tr>\n<td>semantic-zoom-level</td>\n<td>no</td>\n<td>Graph</td>\n<td>int</td>\n<td>1</td>\n<td>Defines the default SZL.</td>\n</tr>\n<tr>\n<td>vertex-status-provider</td>\n<td>no</td>\n<td>Graph</td>\n<td>string</td>\n<td>-</td>\n<td>Defines which Vertex Status Provider should be used, e.g. default, script or propagate</td>\n</tr>\n<tr>\n<td>iconKey</td>\n<td>no</td>\n<td>Node</td>\n<td>string</td>\n<td>generic</td>\n<td>Defines the icon. See <a href=\"#\">Icons</a> for more information.</td>\n</tr>\n<tr>\n<td>Property</td>\n<td>Required</td>\n<td>For element</td>\n<td>Type</td>\n<td>Default</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>---------------</td>\n<td>----------</td>\n<td>-----------------------------------</td>\n<td>---------</td>\n<td>---------</td>\n<td>-----------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>label</td>\n<td>no</td>\n<td>Graph, Node</td>\n<td>string</td>\n<td>-</td>\n<td>Defines a custom label. If not defined, the id is used instead.</td>\n</tr>\n<tr>\n<td>nodeID</td>\n<td>no</td>\n<td>Node</td>\n<td>int</td>\n<td>-</td>\n<td>Allows referencing the Vertex to an OpenNMS node.</td>\n</tr>\n<tr>\n<td>foreignSource</td>\n<td>no</td>\n<td>Node</td>\n<td>string</td>\n<td>-</td>\n<td>Allows referencing the Vertex to an OpenNMS node identified by foreign source and foreign id. Can only be used in combination with foreignID. Please note that this attribute will not be used when the attribute nodeID is set.</td>\n</tr>\n<tr>\n<td>foreignID</td>\n<td>no</td>\n<td>Node</td>\n<td>string</td>\n<td>-</td>\n<td>Allows referencing the Vertex to an OpenNMS node identified by foreign source and foreign id. Can only be used in combination with foreignSource. Please note that this attribute will not be used when the attribute nodeID is set.</td>\n</tr>\n<tr>\n<td>tooltipText</td>\n<td>no</td>\n<td>Node, Edge</td>\n<td>string</td>\n<td></td>\n<td>Defines a custom tooltip. If not defined, the id attribute is used instead.</td>\n</tr>\n<tr>\n<td>level</td>\n<td>no</td>\n<td>Node</td>\n<td>int</td>\n<td>0</td>\n<td>Sets the level of the Vertex which is used by certain layout algorithms i.e. Hierarchical Layout and Grid Layout.</td>\n</tr>\n<tr>\n<td>edge-path-offset</td>\n<td>no</td>\n<td>Graph, Node</td>\n<td>int</td>\n<td>20</td>\n<td>Controls the spacing between the paths drawn for the edges when there are multiple edges connecting two vertices.</td>\n</tr>\n<tr>\n<td>breadcrumb-strategy</td>\n<td>no</td>\n<td>Graph ML</td>\n<td>string</td>\n<td>NONE</td>\n<td>Defines the breadcrumb strategy to use. See Breadcrumbs for more information.</td>\n</tr>\n<tr>\n<td>containerId</td>\n<td>no</td>\n<td>Graph ML</td>\n<td>string</td>\n<td>NONE</td>\n<td>Defines the id of the container. Is required to access the Graph Service ReST API. If none is provided the value is calculated by joining the graph namespaces using a . as separator.</td>\n</tr>\n</tbody>\n</table>\n\n### 3.2.3. Focus Strategies\n\nA **Focus Strategy** defines which Vertices should be added to focus when selecting the Topology. The following strategies are available:\n\n- **EMPTY** No Vertex is added to focus.\n- **ALL** All Vertices are added to focus.\n- **FIRST** The first Vertex is added to focus.\n- **SPECIFIC** Only Vertices which id match the graph’s property `focus-ids` are added to focus.\n3.2.4. Icons\n\nWith the `GraphMLTopoloygProvider` it is not possible to change the icon from the Topology UI. Instead if a custom icon should be used, each node must contain a `iconKey` property referencing an SVG element.\n\n3.2.5. Vertex Status Provider\n\nThe `Vertex Status Provider` calculates the status of the Vertex. There are multiple implementations available which can be configured for each graph: `default`, `script` and `propagate`. If none is specified, there is no status provided at all.\n\n**Default Vertex Status Provider**\n\nThe `default` status provider calculates the status based on the worst unacknowledged alarm associated with the Vertex's node. In order to have a status calculated a (OpenNMS Horizon) node must be associated with the Vertex. This can be achieved by setting the GraphML attribute `nodeID` on the GraphML node accordingly.\n\n**Script Vertex Status Provider**\n\nThe `script` status provider uses scripts similar to the `Edge Status Provider`. Just place Groovy scripts (with file extension .groovy) in the directory `$OPENNMS_HOME/etc/graphml-vertex-status`. All of the scripts will be evaluated and the most severe status will be used for the vertex in the topology's visualization.\n\nIf the script shouldn’t contribute any status to a vertex just return `null`.\n\n**Propagate Vertex Status Provider**\n\nThe `propagate` status provider follows all links from a node to its connected nodes. It uses the status of these nodes to calculate the status by determining the worst one.\n\n3.2.6. Edge Status Provider\n\nIt is also possible to compute a status for each edge in a given graph. Just place Groovy scripts (with file extension .groovy) in the directory `$OPENNMS_HOME/etc/graphml-edge-status`. All of the scripts will be evaluated and the most severe status will be used for the edge in the topology's visualization.\n\nThe following simple Groovy script example will apply a different style and severity if the edge's associated source node is down.\n**Scriptable edge status**\n\n```java\nimport org.opennms.netmgt.model.OnmsSeverity;\nimport org.opennms.features.topology.plugins.topo.graphml.GraphMLEdgeStatus;\n\nif (sourceNode != null && sourceNode.isDown()) {\n return new GraphMLEdgeStatus(OnmsSeverity.WARNING, [\"stroke-dasharray\": \"5,5\", \"stroke\": \"yellow\", \"stroke-width\": \"6\"]);\n} else {\n return new GraphMLEdgeStatus(OnmsSeverity.NORMAL, []);\n}\n```\n\nIf the script shouldn't contribute any status to an edge just return null.\n\n### 3.2.7. Layers\n\nThe `GraphMLTopologyProvider` can handle GraphML files with multiple graphs. Each Graph is represented as a Layer in the Topology UI. If a vertex from one graph has an edge pointing to another graph, one can navigate to that layer.\n\n#### GraphML example defining multiple layers\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<graphml xmlns=\"http://graphml.graphdrawing.org/xmlns\"\n xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n xsi:schemaLocation=\"http://graphml.graphdrawing.org/xmlns http://graphml.graphdrawing.org/xmlns/1.0/graphml.xsd\">\n <!-- Key section -->\n <key id=\"label\" for=\"graphml\" attr.name=\"label\" attr.type=\"string\"/>\n <key id=\"label\" for=\"graph\" attr.name=\"label\" attr.type=\"string\"/>\n <key id=\"label\" for=\"node\" attr.name=\"label\" attr.type=\"string\"/>\n <key id=\"description\" for=\"graph\" attr.name=\"description\" attr.type=\"string\"/>\n <key id=\"namespace\" for=\"graph\" attr.name=\"namespace\" attr.type=\"string\"/>\n <key id=\"preferred-layout\" for=\"graph\" attr.name=\"preferred-layout\" attr.type=\"string\"/>\n <key id=\"focus-strategy\" for=\"graph\" attr.name=\"focus-strategy\" attr.type=\"string\"/>\n <key id=\"focus-ids\" for=\"graph\" attr.name=\"focus-ids\" attr.type=\"string\"/>\n <key id=\"semantic-zoom-level\" for=\"graph\" attr.name=\"semantic-zoom-level\" attr.type=\"int\"/>\n\n <!-- Label for Topology Selection menu -->\n <data key=\"label\">Layer Example</data>\n <graph id=\"regions\">\n <data key=\"namespace\">acme:regions</data>\n <data key=\"label\">Regions</data>\n <data key=\"description\">The Regions Layer.</data>\n <data key=\"preferred-layout\">Circle Layout</data>\n <data key=\"focus-strategy\">ALL</data>\n </graph>\n</graphml>\n```\n<node id=\"north\">\n <data key=\"label\">North</data>\n</node>\n\n<node id=\"west\">\n <data key=\"label\">West</data>\n</node>\n\n<node id=\"south\">\n <data key=\"label\">South</data>\n</node>\n\n<node id=\"east\">\n <data key=\"label\">East</data>\n</node>\n\n<graph id=\"markets\">\n <data key=\"namespace\">acme:markets</data>\n <data key=\"description\">The Markets Layer.</data>\n <data key=\"label\">Markets</data>\n <data key=\"description\">The Markets Layer</data>\n <data key=\"semantic-zoom-level\">1</data>\n <data key=\"focus-strategy\">SPECIFIC</data>\n <data key=\"focus-ids\">north.2</data>\n <node id=\"north.1\">\n <data key=\"label\">North 1</data>\n </node>\n <node id=\"north.2\">\n <data key=\"label\">North 2</data>\n </node>\n <node id=\"north.3\">\n <data key=\"label\">North 3</data>\n </node>\n <node id=\"north.4\">\n <data key=\"label\">North 4</data>\n </node>\n <node id=\"west.1\">\n <data key=\"label\">West 1</data>\n </node>\n <node id=\"west.2\">\n <data key=\"label\">West 2</data>\n </node>\n <node id=\"west.3\">\n <data key=\"label\">West 3</data>\n </node>\n <node id=\"west.4\">\n <data key=\"label\">West 4</data>\n </node>\n <node id=\"south.1\">\n <data key=\"label\">South 1</data>\n </node>\n <node id=\"south.2\">\n <data key=\"label\">South 2</data>\n </node>\n</graph>\n3.2.8. Breadcrumbs\n\nWhen multiple Layers are used it is possible to navigate between them (navigate to option from vertex' context menu). To give the user some orientation breadcrumbs can be enabled with the breadcrumb-strategy property.\n\nThe following strategies are supported:\n\n- **NONE** No breadcrumbs are shown.\n- **SHORTEST_PATH_TO_ROOT** generates breadcrumbs from all visible vertices to the root layer (TopologyProvider). The algorithms assumes a hierarchical graph. Be aware, that all vertices MUST share the same root layer, otherwise the algorithm to determine the path to root does not work.\n\nThe following figure visualizes a graphml defining multiple layers (see below for the graphml definition).\n\n![GraphML Diagram]\n\nFrom the given example, the user can select the Breadcrumb Example Topology Provider from the menu. The user can switch between Layer 1, Layer 2 and Layer 3. In addition for each vertex which has connections to another layer, the user can select the navigate to option from the context menu of that vertex to navigate to the according layer. The user can also search for all vertices and add it\nto focus.\n\nThe following behaviour is implemented:\n\n- If a user navigates from one vertex to a vertex in another layer, the view is switched to that layer and adds all vertices to focus, the source vertex pointed to. The Breadcrumb is `<parent layer name> > <source vertex>`. For example, if a user navigates from Layer1:A2 to Layer2:B1 the view switches to Layer 2 and adds B1 and B2 to focus. In addition Layer 1 > A2 is shown as Breadcrumbs.\n\n- If a user directly switches to another layer, the default focus strategy is applied, which may result in multiple vertices with no unique parent. The calculated breadcrumb is: `<parent layer name> > Multiple <target layer name>`. For example, if a user switches to Layer 3, all vertices of that layer are added to focus (`focus-strategy=ALL`). No unique path to root is found, the following breadcrumb is shown instead: Layer 1 > Multiple Layer 1 > Multiple Layer 2\n\n- If a user adds a vertex to focus, which is not in the current selected layer, the view switches to that layer and only the \"new\" vertex is added to focus. The generated breadcrumb shows the path to root through all layers. For example, the user adds C3 to focus, and the current layer is Layer 1, than the generated breadcrumb is as follows: Layer 1 > A1 > B3.\n\n- Only elements between layers are shown in the breadcrumb. Connections on the same layer are ignored. For example, a user adds C5 to focus, the generated breadcrumb is as follows: Layer 1 > A2 > B2\n\nThe following graphml file defines the above shown graph. Be aware, that the root vertex shown above is generated to help calculating the path to root. It must not be defined in the graphml document.\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<graphml xmlns=\"http://graphml.graphdrawing.org/xmlns\"\n xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n xsi:schemaLocation=\"http://graphml.graphdrawing.org/xmlns\n http://graphml.graphdrawing.org/xmlns/1.0/graphml.xsd\">\n <key id=\"breadcrumb-strategy\" for=\"graphml\" attr.name=\"breadcrumb-strategy\" attr.type=\"string\"></key>\n <key id=\"label\" for=\"all\" attr.name=\"label\" attr.type=\"string\"></key>\n <key id=\"description\" for=\"graph\" attr.name=\"description\" attr.type=\"string\"></key>\n</graphml>\n<graph id=\"L1\">\n <data key=\"label\">Layer 1</data>\n <data key=\"namespace\">acme:layer1</data>\n</graph>\n<graphml xmlns=\"http://graphml.graphdrawing.org/xmlns\"\n xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n xsi:schemaLocation=\"http://graphml.graphdrawing.org/xmlns\n http://graphml.graphdrawing.org/xmlns/1.0/graphml.xsd\">\n <key id=\"focus-strategy\" for=\"graph\" attr.name=\"focus-strategy\" attr.type=\"string\"></key>\n <key id=\"focus-ids\" for=\"graph\" attr.name=\"focus-ids\" attr.type=\"string\"></key>\n <key id=\"preferred-layout\" for=\"graph\" attr.name=\"preferred-layout\" attr.type=\"string\"></key>\n <key id=\"semantic-zoom-level\" for=\"graph\" attr.name=\"semantic-zoom-level\" attr.type=\"int\"></key>\n <data key=\"label\">Breadcrumb Example</data>\n <data key=\"breadcrumb-strategy\">SHORTEST_PATH_TO_ROOT</data>\n <graph id=\"L1\">\n <data key=\"label\">Layer 1</data>\n <data key=\"namespace\">acme:layer1</data>\n```\n<data key=\"focus-strategy\">ALL</data>\n<data key=\"preferred-layout\">Circle Layout</data>\n\n<node id=\"a1\">\n <data key=\"label\">A1</data>\n</node>\n<node id=\"a2\">\n <data key=\"label\">A2</data>\n</node>\n<edge id=\"a1_b3\" source=\"a1\" target=\"b3\"/>\n<edge id=\"a1_b4\" source=\"a1\" target=\"b4\"/>\n<edge id=\"a2_b1\" source=\"a2\" target=\"b1\"/>\n<edge id=\"a2_b2\" source=\"a2\" target=\"b2\"/>\n\n<graph id=\"L2\">\n <data key=\"label\">Layer 2</data>\n <data key=\"focus-strategy\">ALL</data>\n <data key=\"namespace\">acme:layer2</data>\n <data key=\"preferred-layout\">Circle Layout</data>\n <data key=\"semantic-zoom-level\">0</data>\n <node id=\"b1\">\n <data key=\"label\">B1</data>\n </node>\n <node id=\"b2\">\n <data key=\"label\">B2</data>\n </node>\n <node id=\"b3\">\n <data key=\"label\">B3</data>\n </node>\n <node id=\"b4\">\n <data key=\"label\">B4</data>\n </node>\n <edge id=\"b1_c2\" source=\"b1\" target=\"c2\"/>\n <edge id=\"b2_c1\" source=\"b2\" target=\"c1\"/>\n <edge id=\"b3_c3\" source=\"b3\" target=\"c3\"/>\n</graph>\n\n<graph id=\"Layer 3\">\n <data key=\"label\">Layer 3</data>\n <data key=\"focus-strategy\">ALL</data>\n <data key=\"description\">Layer 3</data>\n <data key=\"namespace\">acme:layer3</data>\n <data key=\"preferred-layout\">Grid Layout</data>\n <data key=\"semantic-zoom-level\">1</data>\n <node id=\"c1\">\n <data key=\"label\">C1</data>\n </node>\n <node id=\"c2\">\n <data key=\"label\">C2</data>\n </node>\n <node id=\"c3\">\n <data key=\"label\">C3</data>\n </node>\n</graph>\n3.3. Topologies Updates\n\nIn OpenNMS Horizon the Kafka Producer uses Topologies Updates to send topologies messages to Kafka.\n\nEnhanced Linkd has six OnmsTopologyUpdaters each sending its own NODES, BRIDGE, CDP, ISIS, LLDP and OSPF protocol OnmsTopologyMessage.\n\nKafka Producer implements an OnmsTopologyConsumer that reads the OnmsTopologyMessage to be shared over Kafka.\n\nThe Topologies updates api are available under opennms/features/topologies\n\n3.3.1. OnmsTopologyUpdater\n\nTo set up an implementation class of OnmsTopologyUpdater interface it must be implemented three methods:\n\nOnmsTopology getTopology();\n\nOnmsTopologyProtocol getProtocol() throws OnmsTopologyException;\n\nString getName();\n\n\nIn order to send OnmsTopologyMessage to subscribers the updater should register and send messages using the provided methods into OnmsTopologyDao\n\nTo register use:\n\nregister(OnmsTopologyUpdater updater) Only one updater for protocol is allowed to register over OnmsTopologyDao.\n\nTo send messages to subscriber use:\n\nvoid update(OnmsTopologyUpdater updater,OnmsTopologyMessage message) throws\nOnmsTopologyException;\n\nTo unregister use:\n\n```\nunregister(OnmsTopologyUpdater updater)\n```\n\nRegistering Updaters with OnmsTopologyDao will also provide Topology using OnmsTopologyDao\nto get a Topology for a specific protocol use:\n\n```\nOnmsTopology getTopology(String protocol)\n```\n\n### 3.3.2. OnmsTopologyRef\n\nOnmsTopologyRef is the topology basic interface. All topology defined objects are implementing it.\n\nThe methods defining OnmsTopolgyRef are:\n\nThe Id: a unique String identifier of the topology Object.\n\n```\nString getId();\n```\n\nThe tool tip text: some additional information to describe the topology object.\n\n```\nString getToolTipText();\n```\n\n### 3.3.3. OnmsTopologyMessage\n\nOnmsTopologyMessage is defined by OnmsTopologyProtocol by a TopologyMessageStatus and by an\nOnmsTopologyRef and it is send to all subscriber for the specified protocol by the registered updater\nvia the `OnmsTopologyDao`\n\n### 3.3.4. OnmsTopologyProtocol\n\nOnmsTopologyProtocol represent a protocol. It is defined by a String but it is not case sensitive, CDP\neither cdp and Cdp will define the same protocol.\n\nAn OnmsTopologyUpdater can be an updater for only one protocol.\n\nAn OnmsTopologyConsumer can be a consumer for several protocols.\n\n### 3.3.5. TopologyMessageStatus\n\nTopologyMessageStatus is an enum whose allowed values are: UPDATE or DELETE.\n\nUPDATE message means that the topology message holds information about an OnmsTopologyRef still\navailable in Topology\n\nDELETE message means that the object OnmsTopologyRef has been deleted from topology.\n3.3.6. **OnmsTopology**\n\nA topology is made by vertices and edges each of uniquely identified by an `OnmsTopologyRef`. `OnmsTopology` is a SET of `OnmsTopologyVertex` and a SET of `OnmsTopologyEdge`. Also is possible to set and get a Default Vertex.\n\n3.3.7. **OnmsTopologyVertex**\n\n`OnmsTopologyVertex` implements `OnmsTopologyRef` and represents a vertex.\n\n3.3.8. **OnmsTopologyEdge**\n\n`OnmsTopologyEdge` implements `OnmsTopologyRef` and represents an Edge and is made by a two `OnmsTopologyPort` the source and the target of the edge.\n\n3.3.9. **OnmsTopologyPort**\n\n`OnmsTopologyPort` implements `OnmsTopologyRef` represents a Port belonging to a Vertex so has a property to set and get the `OnmsTopologyVertex`.\n\nThe Port is an element of the Topology because it belongs to an Edge and is the connection element. Two vertices are connected by an Edge by the corresponding Port.\n\n3.3.10. **OnmsTopologyConsumer**\n\nTo set up an implementation class of `OnmsTopologyConsumer` interface it must be implemented three methods:\n\n- `String getName();`\n- `Set<OnmsTopologyProtocol> getProtocols();`\n- `void consume(OnmsTopologyMessage message);`\n\nAn `OnmsTopologyConsumer` consume the `OnmsTopologyMessage` of the specified list `OnmsTopologyProtocol` provided by the getProtocols() method implementing the method void consume(OnmsTopologyMessage message)\n\nIn order to receive `OnmsTopologyMessage` from the registered \"Updaters\", the \"Consumer\" should subscribe `OnmsTopologyDao`\n\nTo subscribe use:\n\n- `void subscribe(OnmsTopologyConsumer consumer)`\n\nTo unsubscribe use:\n\n- `void unsubscribe(OnmsTopologyConsumer consumer)`\nChapter 4. Graph Service API\n\nThis section covers the insides of the new Graph Service API. The Graph Service API was heavily inspired by the GraphML model and the original Topology API.\n\n4.1. Terminology\n\nA Graph consists of any number of points with any number of connections in between. Usually these points are called Nodes, but as Nodes have a specific meaning in OpenNMS Horizon in the context of the Graph Service they are called Vertices (plural of Vertex). The connection between two Vertices are usually called Link, however it also has a specific meaning inside OpenNMS Horizon, thus it is called Edge. A Graph Container contains any number of Graphs. In general an Element can either be a Graph, Vertex or Edge.\n\n4.2. Graph Model\n\n4.2.1. Generic Graph Model\n\nThe Generic Graph Model is very similar to GraphML’s model and consists of the basic elements:\n\n- GenericGraphContainer,\n- GenericGraph,\n- GenericVertex and\n- GenericEdge\n\nEach of the above have besides their designated functionality described in Terminology also properties assigned to them. Some properties are mandatory and determined by the element’s type. Others are optionally and totally up to the entity providing a graph to the system.\n\nThe following rules apply to the Generic Graph Model:\n\n- Each Graph container must be uniquely identified. This identifier is called a container id. The container id must be unique overall containers and graph namespaces.\n- Each Graph must be uniquely identified over all graphs (meaning the namespace must be unique throughout the system). This identifier is called a namespace. Each namespace must be unique overall container ids and graph namespaces.\n- Each Vertex and Edge must be uniquely identified by an identifier. This identifier is called an id. The id must not be unique in the system, but within the graph.\n- Each Vertex and Edge have the same namespace as the Graph they are part of. This allows to uniquely identify vertices and edges throughout the system.\n- Each Graph, Vertex or Edge have additional properties to define their nature in more detail. E.g. a Vertex may contain a label, node or location property.\n- Each Edge contains the source and target id of the Vertex it connects, therefore is ALWAYS directed.\n• Each edge may reference Vertices from a different Graph (namespace). However at least one side must share the same namespace as the edge itself. This is the “owning” side, thus the edge will be a member of that Graph.\n\n| A graph may define a property id besides the property namespace. This is mostly only relevant, when importing graphs via GraphML as each graph element must have an id attribute set. When importing such GraphML each imported graph will have a namespace and id property set. In general, it is recommended, that the value of the attribute id SHOULD be identically to the namespace property even if it MUST NOT. |\n\nRefer to module features/graph/api in package org.opennms.netmgt.graph.api.generic for implementation details.\n\n4.2.2. Domain Graph Model\n\nA Domain Graph Model is a model implementing a use case in its domain using the Generic Graph Model. This can be achieved by simply using the Generic Graph Model and setting the according properties. For more complex use cases a more Java-friendly way - Basic Domain objects are available - to act as a \"view\" on the Generic Graph Model to provide a more convenient implementation. These domain objects don't hold information on their own but provide only access to information that can be deducted from the underlying Generic Model and it's properties.\n\n| For the Domain Graph Model the same rules apply as for the Generic Graph Model. |\n\nSee features/graph/provider/bsm for a domain model using the basic domain graph classes (AbstractDomainGraph, AbstractDomainVertex, etc).\n\nSee features/graph/provider/graphml for a domain model using the Generic Graph Model classes.\n\n4.2.3. Immutability\n\nThe graph container and all it's elements are immutable once created. In order to fully create a container various builders are provided.\n\n4.3. Providers\n\nTo get a new graph or graph container to the system either a GraphContainerProvider or GraphProvider must be implemented and exposed via the OSGi-registry. The latter is a convenient way of exposing a container which only consists of one graph.\n\n4.3.1. Meta Information\n\nLoading a graph container or graph may be very expensive. Especially, if only the meta data are of interest (e.g. label, description). Therefore each provider allows to fetch the meta data only without loading the graph or container.\n4.4. Cache\n\nAll calls to GraphContainerProvider.loadGraphContainer() are cached until OpenNMS Horizon restarts. This means it is up to the implementor to invalidate the cache.\n\nThis can be achieved by manually invoking the org.opennms.netmgt.graph.api.service.GraphContainerCache.invalidate(String containerId) method as the GraphContainerCache is exposed as an OSGi-service. Alternatively a service property can be used to invalidate a cache entry after it was first populated to the cache:\n\n```\n<service interface=\"org.opennms.netmgt.graph.api.service.GraphProvider\" ref=\"applicationGraphProvider\">\n <service-properties>\n <entry key=\"cacheInvalidateInterval\" value=\"300\" /> <!-- seconds -->\n </service-properties>\n</service>\n```\n\n4.5. Search\n\nThe goal behind searching is usually to bring one or more vertices into the focus of the user. Usually the user searches for something like a node label or category name. Mostly, those things do not directly relate to any element in the graph.\n\nTherefore a search always consists of the following process:\n\n1. Search for a concrete item in the system (e.g. node, vertex, category)\n2. Resolve all vertices which match the concrete item.\n\nInternally SearchProvider are used which allow to first make suggestions based on an input. A NodeSearchProvider might return a list of suggestions representing nodes in the system. The NodeSearchProvider knows how to \"resolve\" that selection to a unique set of vertices after the user selected one.\n\n```\nAt the moment searching is ALWAYS performed in the context of a given namespace. Searching over multiple namespaces is not supported or encouraged.\n```\n\n4.6. Focus / Semantic Zoom Level / View\n\nThe focus itself is a list of vertices within the graph. The Semantic Zoom Level (or szl) indicates the number of hops (= distance) a vertex may be away from any vertex within the focus to be shown. If the Semantic Zoom Level is 0 only the vertices in focus are shown.\n\nThe applied Semantic Zoom Level and Focus is called a View of the graph.\n\nIf the focus contains elements which are not part of the graph, they are not shown.\n\nThe Graph Service API allows to create a view on any given graph considering a custom or default\nfocus as well as the semantic zoom level. If no focus is provided when requesting the view, the default focus is applied.\n\n4.7. Listening for Changes\n\nIt is possible to listen for graph or graph container changes. Various listeners can be exposed as an OSGi-service.\n\nThe calculation of changes must be triggered manually. To do so, use the `org.opennms.netmgt.graph.api.updates.GraphNotificationService` service, which is exposed as an OSGi service.\n\nRefer to package `org.opennms.netmgt.graph.api.updates` in module `features/graph/api` for available options.\n\n4.8. Persistence\n\nEach graph or graph container can be persisted to the database using the `org.opennms.netmgt.graph.api.persistence.GraphRepository`.\n\n4.9. Enrichment\n\nEnrichment is the process to enrich the view of the graph with additional information, usually used when the enriched data is expensive to load/calculate, e.g. load node data or calculate the status.\n\nDue to performance considerations, enrichment only works on the view of a graph and cannot be performed on the full graph.\n\n4.9.1. Build in Enrichment\n\nNode Enrichment\n\nBy default all vertices can be enriched with node information if `Node Enrichment` is enabled. To enable the enrichment of node information, the property `enrichment.resolveNodes` must be set to `true` on the graph.\n\nAfterwards each vertex which either has a `nodeID` (integer) or `foreignSource` (string) and `foreignID` (string) property assigned will be enriched if a node with that information is found in the system. A shorter version in form of `nodeCriteria=<foreignSource>::<foreignID>` is also available.\n\n4.10. ReST API\n\nThe `Graph Service API` provides a ReST API which is documented in detail [here](#).\n\nThe Graph Service API ReST endpoints serializes the requested graph container, graph or view in json. As the container and each element within that container may contain custom properties, the type of the property is not static. This means, each `GraphContainerProvider` (or `GraphProvider`) can set properties on any element using a type which is only known by the domain the graph container is\ncreated in. However when serializing this object as JSON it is not clear to the ReST endpoint how to do that. In order to allow these values to be set as properties anyways, a custom org.opennms.netmgt.graph.rest.api.PropertyConverter can be exposed as an OSGi service.\n\n4.11. Limitations\n\nThe following limitations are known for the Graph Service API:\n\n- Status of vertices is not exposed\n- custom images/icons cannot be set\n- custom edge/vertex status providers are not implemented\n- VMWare Topology Provider not fully migrated\n- EnhancedLinkd Topology Provider not fully migrated\nChapter 5. CORS Support\n\n5.1. Why do I need CORS support?\n\nBy default, many browsers implement a same origin policy which prevents making requests to a resource, on an origin that's different from the source origin.\n\nFor example, a request originating from a page served from http://www.opennms.org to a resource on http://www.adventuresinoss.com would be considered a cross origin request.\n\nCORS (Cross Origin Resource Sharing) is a standard mechanism used to enable cross origin requests.\n\nFor further details, see:\n\n- Mozilla’s HTTP access control (CORS)\n- W3C’s CORS Spec\n\n5.2. How can I enable CORS support?\n\nCORS support for the REST interface (or any other part of the Web UI) can be enabled as follows:\n\n1. Open 'OPENNMS_HOME/jetty-webapps/opennms/WEB-INF/web.xml' for editing.\n2. Apply the CORS filter to the '/rest/' path by removing the comments around the <filter-mapping> definition. The result should look like:\n\n```xml\n<!-- Uncomment this to enable CORS support -->\n<filter-mapping>\n <filter-name>CORS Filter</filter-name>\n <url-pattern>/rest/*</url-pattern>\n</filter-mapping>\n```\n\n3. Restart OpenNMS Horizon\n\n5.3. How can I configure CORS support?\n\nCORS support is provided by the org.ebaysf.web.cors.CORSFilter servlet filter.\n\nParameters can be configured by modifying the filter definition in the 'web.xml' file referenced above.\n\nBy default, the allowed origins parameter is set to '*'.\n\nThe complete list of parameters supported are available from:\n\n- https://github.com/ebay/cors-filter\nChapter 6. ReST API\n\nA RESTful interface is a web service conforming to the REST architectural style as described in the book RESTful Web Services. This page describes the RESTful interface for OpenNMS Horizon.\n\n6.1. ReST URL\n\nThe base URL for Rest Calls is: http://opennmsserver:8980/opennms/rest/\n\nFor instance, http://localhost:8980/opennms/rest/alarms/ will give you the current alarms in the system.\n\n6.2. Authentication\n\nUse HTTP Basic authentication to provide a valid username and password. By default you will not receive a challenge, so you must configure your ReST client library to send basic authentication proactively.\n\n6.3. Data format\n\nJersey allows ReST calls to be made using either XML or JSON. By default a request to the API is returned in XML. XML is delivered without namespaces. Please note: If a namespace is added manually in order to use a XML tool to validate against the XSD (like xmllint) it won't be preserved when OpenNMS updates that file. The same applies to comments. To get JSON encoded responses one has to send the following header with the request: Accept: application/json.\n\n6.4. Standard Parameters\n\nThe following are standard params which are available on most resources (noted below)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>limit</td>\n<td>integer, limiting the number of results. This is particularly handy on events and notifications, where an accidental call with no limit could result in many thousands of results being returned, killing either the client or the server. If set to 0, then no limit applied</td>\n</tr>\n<tr>\n<td>offset</td>\n<td>integer, being the numeric offset into the result set from which results should start being returned. E.g., if there are 100 result entries, offset is 15, and limit is 10, then entries 15-24 will be returned. Used for pagination</td>\n</tr>\n<tr>\n<td>Parameter</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-----------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>Filtering: All properties of the entity being accessed can be specified as parameters in either the URL (for GET) or the form value (for PUT and POST). If so, the value will be used to add a filter to the result. By default, the operation is equality, unless the comparator parameter is sent, in which case it applies to all comparisons in the filter. Multiple properties will result in an AND operation between the filter elements. Available comparators are:</td>\n<td></td>\n</tr>\n<tr>\n<td>eq</td>\n<td>Checks for equality</td>\n</tr>\n<tr>\n<td>ne</td>\n<td>Checks for non-equality</td>\n</tr>\n<tr>\n<td>ilike</td>\n<td>Case-insensitive wildcarding (% is the wildcard)</td>\n</tr>\n<tr>\n<td>like</td>\n<td>Case-sensitive wildcarding (% is the wildcard)</td>\n</tr>\n<tr>\n<td>gt</td>\n<td>Greater than</td>\n</tr>\n<tr>\n<td>lt</td>\n<td>Less than</td>\n</tr>\n<tr>\n<td>ge</td>\n<td>Greater than or equal</td>\n</tr>\n<tr>\n<td>le</td>\n<td>Less than or equal</td>\n</tr>\n</tbody>\n</table>\n\nIf the value null is passed for a given property, then the obvious operation will occur (comparator will be ignored for that property). notnull is handled similarly.\n\n- **Ordering:** If the parameter orderBy is specified, results will be ordered by the named property. Default is ascending, unless the order parameter is set to desc (any other value will default to ascending)\n\n### 6.5. Standard filter examples\n\nTake /events as an example.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/events?eventUei=uei.opennms.org/internal/rtc/subscribe</td>\n<td>would return the first 10 events with the rtc subscribe UEI, (10 being the default limit for events)</td>\n</tr>\n<tr>\n<td>/events?eventUei=uei.opennms.org/internal/rtc/subscribe&limit=0</td>\n<td>would return all the rtc subscribe events (potentially quite a few)</td>\n</tr>\n<tr>\n<td>/events?id=100&comparator=gt</td>\n<td>would return the first 10 events with an id greater than 100</td>\n</tr>\n<tr>\n<td>/events?eventAckTime=notnull</td>\n<td>would return the first 10 events that have a non-null Ack time (i.e. those that have been acknowledged)</td>\n</tr>\n<tr>\n<td>/events?eventAckTime=notnull&id=100&comparator=gt&limit=20</td>\n<td>would return the first 20 events that have a non-null Ack time and an id greater than 100. Note that the notnull value causes the comparator to be ignored for eventAckTime</td>\n</tr>\n<tr>\n<td>Resource</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>/events?eventAckTime=2008-07-28T04:41:30.530%2B12:00&id=100&comparator=gt&limit=20</td>\n<td>would return the first 20 events that have were acknowledged after 28th July 2008 at 4:41am (+12:00), and an id greater than 100. Note that the same comparator applies to both property comparisons. Also note that you must URL encode the plus sign when using GET.</td>\n</tr>\n<tr>\n<td>/events?orderBy=id&order=desc</td>\n<td>would return the 10 latest events inserted (probably, unless you've been messing with the id's)</td>\n</tr>\n<tr>\n<td>/events?location.id=MINION</td>\n<td>would return the first 10 events associated with some node in location 'MINION'</td>\n</tr>\n</tbody>\n</table>\n\n### 6.6. HTTP Return Codes\n\nThe following apply for OpenNMS Horizon 18 and newer.\n\n- DELETE requests are going to return a 202 (ACCEPTED) if they are performed asynchronously otherwise they return a 204 (NO_CONTENT) on success.\n- All the PUT requests are going to return a 204 (NO_CONTENT) on success.\n- All the POST requests that can either add or update an entity are going to return a 204 (NO_CONTENT) on success.\n- All the POST associated to resource addition are going to return a 201 (CREATED) on success.\n- All the POST requests where it is required to return an object will return a 200 (OK).\n- All the requests excepts GET for the Requisitions end-point and the Foreign Sources Definitions end-point will return 202 (ACCEPTED). This is because all the requests are actually executed asynchronously and there is no way to know the status of the execution, or wait until the processing is done.\n- If a resource is not modified during a PUT request, a NOT_MODIFIED will be returned. A NO_CONTENT will be returned only on a success operation.\n- All GET requests are going to return 200 (OK) on success.\n- All GET requests are going to return 404 (NOT_FOUND) when a single resource doesn't exist; but will return 400 (BAD_REQUEST), if an intermediate resource doesn't exist. For example, if a specific IP doesn't exist on a valid node, return 404. But, if the IP is valid and the node is not valid, because the node is an intermediate resource, a 400 will be returned.\n- If something not expected is received from the Service/DAO Layer when processing any HTTP request, like an exception, a 500 (INTERNAL_SERVER_ERROR) will be returned.\n- Any problem related with the incoming parameters, like validations, will generate a 400 (BAD_REQUEST).\n\n### 6.7. Identifying Resources\n\nSome endpoints deal in resources, which are identified by Resource IDs. Since every resource is\nultimately parented under some node, identifying the node which contains a resource is the first step in constructing a resource ID. Two styles are available for identifying the node in a resource ID:\n\n<table>\n<thead>\n<tr>\n<th>Style</th>\n<th>Description</th>\n<th>Example</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>node[ID]</td>\n<td>Identifies a node by its database ID, which is always an integer</td>\n<td>node[42]</td>\n</tr>\n<tr>\n<td>node[FS:FID]</td>\n<td>Identifies a node by its foreign-source name and foreign-ID, joined by a single colon</td>\n<td>node[Servers:115da833-0957-4471-b496-a731928c27dd]</td>\n</tr>\n</tbody>\n</table>\n\nThe node identifier is followed by a period, then a resource-type name and instance name. The instance name’s characteristics may vary from one resource-type to the next. A few examples:\n\n<table>\n<thead>\n<tr>\n<th>Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>nodeSnmp[]</td>\n<td>Node-level (scalar) performance data for the node in question. This type is the only one where the instance identifier is empty.</td>\n</tr>\n<tr>\n<td>interfaceSnmp[eth0-04013f75f101]</td>\n<td>A layer-two interface as represented by a row in the SNMP ifTable. The instance identifier is composed of the interface’s ifName and its ifPhysAddress (if it has one).</td>\n</tr>\n<tr>\n<td>dskIndex[_root_fs]</td>\n<td>The root filesystem of a node running the Net-SNMP management agent.</td>\n</tr>\n</tbody>\n</table>\n\nPutting it all together, here are a few well-formed resource IDs:\n\n- node[1].nodeSnmp[]\n- node[42].interfaceSnmp[eth0-04013f75f101]\n- node[Servers:115da833-0957-4471-b496-a731928c27dd].dskIndex[_root_fs]\n\n### 6.8. Expose ReST services via OSGi\n\nIn order to expose a ReST service via OSGi the following steps must be followed:\n\n1. Define an interface, containing java jax-rs annotations\n2. Define a class, implementing that interface\n3. Create an OSGi bundle which exports a service with the interface from above\n\n#### 6.8.1. Define a ReST interface\n\nAt first a public interface must be created which must contain jax-rs annotations.\n@Path(\"/datachoices\") ①\ndpublic interface DataChoiceRestService {\n\n @POST ②\n void updateCollectUsageStatisticFlag(@Context HttpServletRequest request,\n @QueryParam(\"action\") String action);\n\n @GET\n @Produces(value={MediaType.APPLICATION_JSON})\n UsageStatisticsReportDTO getUsageStatistics();\n}\n\n① Each ReST interface must either have a @Path or @Provider annotation. Otherwise it is not considered a ReST service.\n\n② Use jax-rs annotations, such as @Post, @Get, @Put, @Path, etc. to define the ReST service.\n\n6.8.2. Implement a ReST interface\n\nA class must implement the ReST interface.\n\nThe class may or may not repeat the jax-rs annotations from the interface. This is purely for readability. Changing or adding different jax-rs annotations on the class, won't have any effect.\n\npublic class DataChoiceRestServiceImpl implements DataChoiceRestService {\n\n @Override\n public void updateCollectUsageStatisticFlag(HttpServletRequest request, String action) {\n // do something\n }\n\n @Override\n public UsageStatisticsReportDTO getUsageStatistics() {\n return null;\n }\n}\n\n6.8.3. Export the ReST service\n\nAt last the ReST service must be exported via the bundlecontext. This can be either achieved using an Activator or the blueprint mechanism.\nCreate the ReST implementation class\n\nExport the ReST service\n\nDefine where the ReST service will be exported to, e.g. /rest, /api/v2, but also completely different paths can be used. If not defined, /services is used.\n\nFor a full working example refer to the datachoices feature.\n\n6.9. Currently Implemented Interfaces\n\n6.9.1. Acknowledgements\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/acks</td>\n<td>Get a list of acknowledgements.</td>\n</tr>\n<tr>\n<td>/acks/count</td>\n<td>Get the number of acknowledgements. (Returns plaintext, rather than XML or JSON.)</td>\n</tr>\n<tr>\n<td>/acks/{id}</td>\n<td>Get the acknowledgement specified by the given ID.</td>\n</tr>\n</tbody>\n</table>\n\nGETs (Reading Data)\n\nPOSTs (Setting Data)\n### Usage examples with curl\n\n**Acknowledge notification #3**\n\n```bash\ncurl -u 'admin:admin' -X POST -d notifId=3 -d action=ack\nhttp://localhost:8980/opennms/rest/acks\n```\n\n**Escalate alarm #42**\n\n```bash\ncurl -u 'admin:admin' -X POST -d alarmId=42 -d action=esc\nhttp://localhost:8980/opennms/rest/acks\n```\n\n### 6.9.2. Alarm Statistics\n\nIt is possible to get some basic statistics on alarms, including the number of acknowledged alarms, total alarms, and the newest and oldest of acknowledged and unacknowledged alarms.\n\n#### GETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/stats/alarms</td>\n<td>Returns statistics related to alarms. Accepts the same Hibernate parameters</td>\n</tr>\n<tr>\n<td></td>\n<td>that you can pass to the /alarms ReST service.</td>\n</tr>\n<tr>\n<td>/stats/alarms/by-severity</td>\n<td>Returns the statistics related to alarms, one per severity. You can</td>\n</tr>\n<tr>\n<td></td>\n<td>optionally pass a list of severities to the severities query parameter</td>\n</tr>\n<tr>\n<td></td>\n<td>to limit it to the specified severities. (eg, GET</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.3. Alarms\n\n- the default offset is 0, the default limit is 10 results. To get all results, use `limit=0` as a parameter on the URL (ie, GET /events?limit=0).\n\n#### GETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/alarms</td>\n<td>Get a list of alarms.</td>\n</tr>\n<tr>\n<td>Resource</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>-----------------------</td>\n<td>-------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>/alarms/count</td>\n<td>Get the number of alarms. (Returns plaintext, rather than XML or JSON.)</td>\n</tr>\n<tr>\n<td>/alarms/{id}</td>\n<td>Get the alarms specified by the given ID.</td>\n</tr>\n</tbody>\n</table>\n\nNote that you can also query by severity, like so:\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/alarms?comparator=ge&severity=MINOR</td>\n<td>Get the alarms with a severity greater than or equal to MINOR.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Data)**\n\nPUT requires form data using application/x-www-form-urlencoded as a Content-Type.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/alarms/{id}?ack='true' //false'</td>\n<td>Acknowledges (or unacknowledges) an alarm.</td>\n</tr>\n<tr>\n<td>/alarms?x=y&...&ack='true;false'</td>\n<td>Acknowledges (or unacknowledges) alarms matching the additional query parameters. eg, /alarms?node.id=4&ack=true</td>\n</tr>\n</tbody>\n</table>\n\n**New in OpenNMS 1.11.0**\n\nIn OpenNMS 1.11.0, some additional features are supported in the alarm ack API:\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/alarms/{id}?clear=true</td>\n<td>Clears an alarm.</td>\n</tr>\n<tr>\n<td>/alarms/{id}?escalate=true</td>\n<td>Escalates an alarm. eg, NORMAL → MINOR, MAJOR → CRITICAL, etc.</td>\n</tr>\n<tr>\n<td>/alarms?x=y&...&clear=true</td>\n<td>Clears alarms matching the additional query parameters.</td>\n</tr>\n<tr>\n<td>/alarms?x=y&...&escalate=true</td>\n<td>Escalates alarms matching the additional query parameters.</td>\n</tr>\n</tbody>\n</table>\n\nAdditionally, when acknowledging alarms (ack=true) you can now specify an **ackUser** parameter. You will only be allowed to **ack** as a different user IF you are PUTting as an authenticated user who is in the **admin** role.\n\n**v2 API**\n\nSince Horizon 20.1.0, an alarms endpoint has been available in the v2 API that uses FIQL for querying.\n\nExamples:\n\n- /api/v2/alarms?_s=alarm.reductionKey==uei.opennms.org/nodes/nodeDown::*\n• /api/v2/alarms?_s=alarm.uei==uei.opennms.org/nodes/nodeDown\n• /api/v2/alarms?_s=alarm.ipAddr==127.0.0.1\n• /api/v2/alarms?_s=node.label==localhost\n\nIf your query string includes a FIQL reserved character like a comma (,) or a semicolon (;) you need to double percent-escape it.\n\nSuppose you have a service with a comma in the name, like `COMMA,SERVICE` and you want to retrieve all the alarms for its failure. Your query would look like `/api/v2/alarms?_s=alarm.reductionKey==uei.opennms.org/nodes/nodeLostService::*:COMMA%252CSERVIC E`.\n\n### 6.9.4. Alarm History\n\nThe *Alarm History API* can be used to retrieve state changes and point-in-time snapshots for alarms.\n\nThis endpoint is only available when the *Alarm History* feature is enabled. See the Administrators Guide for details.\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/alarms/history/{alarmId}/states</td>\n<td>Retrieve the complete set of state changes for the given alarm.</td>\n</tr>\n<tr>\n<td>/alarms/history/{alarmId}</td>\n<td>Retrieve the last known state of an alarm at the given time.</td>\n</tr>\n<tr>\n<td>/alarms/history</td>\n<td>Retrieve the last known state of all alarms which were active at the given time.</td>\n</tr>\n</tbody>\n</table>\n\n- **name**: default\n- **matchType**: alarm-id\n - By default we lookup alarms based on the given database id. This property can be used to change the matching behaviour to lookup by reduction key instead.\n- **at**: (current time)\n - Timestamp in milliseconds.\n\n### 6.9.5. Events\n\n**GETs (Reading Data)**\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/events</td>\n<td>Get a list of events. The default for offset is 0, and the default for limit is 10. To get all results, use limit=0 as a parameter on the URL (ie, GET /events?limit=0).</td>\n</tr>\n<tr>\n<td>/events/count</td>\n<td>Get the number of events. (Returns plaintext, rather than XML or JSON.)</td>\n</tr>\n<tr>\n<td>/events/{id}</td>\n<td>Get the event specified by the given ID.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Data)**\n\n**PUT** requires form data using application/x-www-form-urlencoded as a Content-Type.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/events/{id}?ack=''(true;false)</td>\n<td>Acknowledges (or unacknowledges) an event.</td>\n</tr>\n<tr>\n<td>/events?x=y&...&ack=''(true;false)</td>\n<td>Acknowledges (or unacknowledges) the matching events.</td>\n</tr>\n</tbody>\n</table>\n\n**POSTs (Adding Data)**\n\nPOST requires XML (application/xml) or JSON (application/json) as its Content-Type.\n\nSee ${OPENNMS_HOME}/share/xsds/event.xsd for the reference schema.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/events</td>\n<td>Publish an event on the event bus.</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.6. Categories\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/categories</td>\n<td>Get all configured categories.</td>\n</tr>\n<tr>\n<td>/categories/{category}</td>\n<td>Get the category specified by the given name.</td>\n</tr>\n<tr>\n<td>/categories/{category}/nodes/{node}</td>\n<td>Get the category specified by the given name for the given node (similar to /nodes/{node}/categories/{category})</td>\n</tr>\n<tr>\n<td>/categories/nodes/{node}</td>\n<td>Get the categories for a given node (similar to /nodes/{node}/categories)</td>\n</tr>\n<tr>\n<td>/categories/groups/{group}</td>\n<td>Get the categories for a given user group (similar to /groups/{group}/categories)</td>\n</tr>\n</tbody>\n</table>\nPOSTs (Adding Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/categories</td>\n<td>Adds a new category.</td>\n</tr>\n</tbody>\n</table>\n\nPUTs (Modifying Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/categories/{category}</td>\n<td>Update the specified category</td>\n</tr>\n<tr>\n<td>/categories/{category}/nodes/{node}</td>\n<td>Modify the category with the given node ID and name (similar to /nodes/{node}/categories/{category})</td>\n</tr>\n<tr>\n<td>/categories/{category}/groups/{group}</td>\n<td>Add the given category to the given user group (similar to /groups/{group}/categories/{category})</td>\n</tr>\n</tbody>\n</table>\n\nDELETEs (Removing Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/categories/{category}</td>\n<td>Delete the specified category</td>\n</tr>\n<tr>\n<td>/categories/{category}/nodes/{node}</td>\n<td>Remove the given category from the given node (similar to /nodes/{node}/categories/{category})</td>\n</tr>\n<tr>\n<td>/categories/{category}/groups/{group}</td>\n<td>Remove the given category from the given user group (similar to /groups/{group}/categories/{category})</td>\n</tr>\n</tbody>\n</table>\n\n6.9.7. Flow API\n\nThe Flow API can be used to retrieve summary statistics and time series data derived from persisted flows.\n\nUnless specific otherwise, all unit of time are expressed in milliseconds.\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/flows/count</td>\n<td>Retrieve the number of flows available</td>\n</tr>\n<tr>\n<td>/flows/exporters</td>\n<td>Retrieve basic information for the exporter nodes that have flows available</td>\n</tr>\n<tr>\n<td>/flows/exporters/{nodeCriteria}</td>\n<td>Retrieve detailed information about a specific exporter node</td>\n</tr>\n<tr>\n<td>/flows/applications</td>\n<td>Retrieve traffic summary statistics for the top N applications or specific applications</td>\n</tr>\n<tr>\n<td>Resource</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>/flows/applications/enumerate</td>\n<td>Retrieve a list of the applications with flows</td>\n</tr>\n<tr>\n<td>/flows/applications/series</td>\n<td>Retrieve time series metrics for the top N applications or specific applications</td>\n</tr>\n<tr>\n<td>/flows/conversations</td>\n<td>Retrieve traffic summary statistics for the top N conversations or specific conversations</td>\n</tr>\n<tr>\n<td>/flows/conversations/enumerate</td>\n<td>Retrieve a list of the conversations with flows</td>\n</tr>\n<tr>\n<td>/flows/conversations/series</td>\n<td>Retrieve time series metrics for the top N conversations or specific conversations</td>\n</tr>\n<tr>\n<td>/flows/hosts</td>\n<td>Retrieve traffic summary statistics for the top N hosts or specific hosts</td>\n</tr>\n<tr>\n<td>/flows/hosts/enumerate</td>\n<td>Retrieve a list of the hosts with flows</td>\n</tr>\n<tr>\n<td>/flows/hosts/series</td>\n<td>Retrieve time series metrics for the top N hosts or specific hosts</td>\n</tr>\n</tbody>\n</table>\n\nAll of the endpoints support the following query string parameters to help filter the results:\n\nThe given filters are combined using a logical **AND**. There is no support for using **OR** logic, or combinations thereof.\n\n<table>\n<thead>\n<tr>\n<th>name</th>\n<th>default</th>\n<th>comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>start</td>\n<td>-14400000</td>\n<td>Timestamp in milliseconds. If > 0, the timestamp is relative to the UNIX epoch (January 1st 1970 00:00:00 AM). If < 0, the timestamp is relative to the end option (i.e.: default value is 4 hours ago).</td>\n</tr>\n<tr>\n<td>end</td>\n<td>0</td>\n<td>Timestamp in milliseconds. If <= 0, the effective value will be the current timestamp.</td>\n</tr>\n<tr>\n<td>ifIndex</td>\n<td>(none)</td>\n<td>Filter for flows that came in through the given SNMP interface.</td>\n</tr>\n</tbody>\n</table>\nThe exporters endpoints do not support any parameters.\n\nThe applications/enumerate endpoint also supports:\n\n<table>\n<thead>\n<tr>\n<th>name</th>\n<th>default</th>\n<th>comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>limit</td>\n<td>10</td>\n<td>Number of applications with flows to return</td>\n</tr>\n<tr>\n<td>prefix</td>\n<td>""</td>\n<td>If provided, filters the results to only include applications with names that start with the given prefix (using fuzzy matching)</td>\n</tr>\n</tbody>\n</table>\n\nThe applications and applications/series endpoints also support:\n\n<table>\n<thead>\n<tr>\n<th>name</th>\n<th>default</th>\n<th>comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>N</td>\n<td>none</td>\n<td>Number of top entries (determined by total bytes transferred) to return</td>\n</tr>\n<tr>\n<td>includeOther</td>\n<td>false</td>\n<td>When set to true the results will also include an additional row or column that contains the bytes transferred for the flows that fall outside of the selected set</td>\n</tr>\n<tr>\n<td>application</td>\n<td>none</td>\n<td>If provided, returns only flow series that match the given application(s). This field can be repeated for any number of applications to be included in the query</td>\n</tr>\n</tbody>\n</table>\n\nBoth endpoints require one of N or application query parameters to be set and will return an error if neither or both are set.\n\nThe conversations/enumerate endpoint also supports:\n<table>\n<thead>\n<tr>\n<th>name</th>\n<th>default</th>\n<th>comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>limit</td>\n<td>10</td>\n<td>Number of hosts with flows to return</td>\n</tr>\n<tr>\n<td>location</td>\n<td>".*"</td>\n<td>If provided, filters the results to only include conversations matching the given location regex pattern</td>\n</tr>\n<tr>\n<td>protocol</td>\n<td>".*"</td>\n<td>If provided, filters the results to only include conversations matching the given protocol regex pattern</td>\n</tr>\n<tr>\n<td>lower</td>\n<td>".*"</td>\n<td>If provided, filters the results to only include conversations matching the given lower IP address regex pattern</td>\n</tr>\n<tr>\n<td>upper</td>\n<td>".*"</td>\n<td>If provided, filters the results to only include conversations matching the given upper IP address regex pattern</td>\n</tr>\n<tr>\n<td>application</td>\n<td>".*"</td>\n<td>If provided, filters the results to only include conversations matching the given application regex pattern</td>\n</tr>\n</tbody>\n</table>\n\nThe conversations and conversations/series endpoints also supports:\n\n<table>\n<thead>\n<tr>\n<th>name</th>\n<th>default</th>\n<th>comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>N</td>\n<td>10</td>\n<td>Number of top entries (determined by total bytes transferred) to return</td>\n</tr>\n<tr>\n<td>includeOther</td>\n<td>false</td>\n<td>When set to true the results will also include an additional row or column that contains the bytes transferred for the flows that fall outside of selected set.</td>\n</tr>\n<tr>\n<td>conversation</td>\n<td>none</td>\n<td>If provided, returns only flow series that match the given conversation(s). This field can be repeated for any number of conversations to be included in the query.</td>\n</tr>\n</tbody>\n</table>\n### Name | Default | Comment\n--- | --- | ---\nhostname_mode | \"replace\" | Controls how IP addresses are replaced with hostnames if available:\n- replace will replace the IP with the hostname\n- append will append the hostname to the IP address\n- hide will not show the hostname at all\n\n- Make sure to URL encode the conversation value in your request.\n\nBoth endpoints require one of `N` or `conversation` query parameters to be set and will return an error if neither or both are set.\n\n**The conversations/series endpoint also supports:**\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Default</th>\n<th>Comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>step</td>\n<td>300000</td>\n<td>Requested time interval between rows.</td>\n</tr>\n</tbody>\n</table>\n\n**The hosts/enumerate endpoint also supports:**\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Default</th>\n<th>Comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>limit</td>\n<td>10</td>\n<td>Number of hosts with flows to return</td>\n</tr>\n<tr>\n<td>pattern</td>\n<td>".*"</td>\n<td>If provided, filters the results to only include hosts with names that match the given regex pattern</td>\n</tr>\n</tbody>\n</table>\n\n**The hosts and hosts/series endpoints also support:**\n\n<table>\n<thead>\n<tr>\n<th>Name</th>\n<th>Default</th>\n<th>Comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>N</td>\n<td>none</td>\n<td>Number of top entries (determined by total bytes transferred) to return</td>\n</tr>\n<tr>\n<td>name</td>\n<td>default</td>\n<td>comment</td>\n</tr>\n<tr>\n<td>---------------</td>\n<td>---------</td>\n<td>-----------------------------------------------------------------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>includeOther</td>\n<td>false</td>\n<td>When set to true the results will also include an additional row or column that contains the bytes transferred for the flows that fall outside of the selected set.</td>\n</tr>\n<tr>\n<td>host</td>\n<td>none</td>\n<td>If provided, returns only flow series that match the given host(s). This field can be repeated for any number of hosts to be included in the query.</td>\n</tr>\n</tbody>\n</table>\n\nBoth endpoints require one of `N` or `host` query parameters to be set and will return an error if neither or both are set.\n\n**Examples**\n\n*Retrieve the number of flows persisted in the last 4 hours*\n\n```\ncurl -u admin:admin http://localhost:8980/opennms/rest/flows/count\n```\n\n**Response**\n\n```\n915\n```\n\n*Retrieve traffic summary for top 10 applications in the last 4 hours*\n\n```\ncurl -u admin:admin http://localhost:8980/opennms/rest/flows/applications\n```\n\n**Response**\n\n```\n{\n \"start\": 1513788044417,\n \"end\": 1513802444417,\n \"headers\": [\"Application\", \"Bytes In\", \"Bytes Out\"],\n \"rows\": [\n [\"https\", 48789, 136626],\n [\"http\", 12430, 5265]\n ]\n}\n```\nRetrieve traffic summary for top 10 conversations in the last 4 hours\n\ncurl -u admin:admin http://localhost:8980/opennms/rest/flows/conversations\n\nResponse\n\n```json\n{\n \"start\": 1513788228224,\n \"end\": 1513802628224,\n \"rows\": [\n [\"Default\", 17, \"10.0.2.15\", 33816, \"172.217.0.66\", 443, 12166, 117297],\n [\"Default\", 17, \"10.0.2.15\", 32966, \"172.217.0.70\", 443, 5042, 107542],\n [\"Default\", 17, \"10.0.2.15\", 54087, \"172.217.0.67\", 443, 55393, 5781],\n [\"Default\", 17, \"10.0.2.15\", 58046, \"172.217.0.70\", 443, 4284, 46986],\n [\"Default\", 6, \"10.0.2.15\", 39300, \"69.172.216.58\", 80, 969, 48178],\n [\"Default\", 17, \"10.0.2.15\", 48691, \"64.233.176.154\", 443, 8187, 39847],\n [\"Default\", 17, \"10.0.2.15\", 39933, \"172.217.0.65\", 443, 1158, 33913],\n [\"Default\", 17, \"10.0.2.15\", 60751, \"216.58.218.4\", 443, 5504, 24957],\n [\"Default\", 17, \"10.0.2.15\", 51972, \"172.217.0.65\", 443, 2666, 22556],\n [\"Default\", 6, \"10.0.2.15\", 46644, \"31.13.65.7\", 443, 459, 16952]\n ]\n}\n```\n\nRetrieve time series data for top 3 applications in the last 4 hours\n\ncurl -u admin:admin\nhttp://localhost:8980/opennms/rest/flows/applications/series?N=3&includeOther=true&step=3600000\nRetrieve time series data for top 3 conversations in the last 4 hours\n\ncurl -u admin:admin\n\n```json\n{\n \"start\": 1516292071742,\n \"end\": 1516306471742,\n \"columns\": [\n {\n \"label\": \"domain\",\n \"ingress\": true\n },\n {\n \"label\": \"https\",\n \"ingress\": true\n },\n {\n \"label\": \"http\",\n \"ingress\": true\n },\n {\n \"label\": \"Other\",\n \"ingress\": true\n }\n ],\n \"timestamps\": [\n 1516291200000,\n 1516294800000,\n 1516298400000\n ],\n \"values\": [\n [9725, 12962, 9725],\n [70665, 125044, 70585],\n [10937, 13141, 10929],\n [1976, 2508, 2615]\n ]\n}\n```\n6.9.8. Flow Classification API\n\nThe Flow Classification API can be used to update, create or delete flow classification rules.\nIf not otherwise specified the Content-Type of the response is application/json.\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/classifications</td>\n<td>Retrieve a list of all enabled rules. The request is limited to 10 items by default. Setting limit to 0 returns ALL enabled rules.</td>\n</tr>\n<tr>\n<td>/classifications/{id}</td>\n<td>Retrieve the rule identified by {id}.</td>\n</tr>\n<tr>\n<td>/classifications/groups</td>\n<td>Retrieve all existing groups. The request is limited to 10 items by default. Setting limit to 0 returns ALL enabled rules.</td>\n</tr>\n<tr>\n<td>/classifications/groups/{id}</td>\n<td>Retrieve the group identified by {id}. Supports downloading all rules of the given group in CSV format. For this, set the accept header: Accept: text/comma-separated-values.</td>\n</tr>\n<tr>\n<td>/classifications/protocols</td>\n<td>Retrieve all supported tcp protocols.</td>\n</tr>\n</tbody>\n</table>\n\nThe /classifications endpoint supports the following url parameters:\n\n- name\n- comment\n- groupFilter\n- (none): The group to filter the rules by. Should be the id retrieved by /classifications/groups. It is not possible to retrieve the rules for a disabled group.\n- query\n\nExamples\n\nRetrieve all enabled rules\n\n```bash\ncurl -X GET -u admin:admin http://localhost:8980/opennms/rest/classifications\n```\n[{\n \"group\": {\n \"description\": \"Classification rules defined by the user\",\n \"enabled\": true,\n \"id\": 2,\n \"name\": \"user-defined\",\n \"position\": 10,\n \"readOnly\": false,\n \"ruleCount\": 1\n },\n \"id\": 1,\n \"ipAddress\": null,\n \"name\": \"http\",\n \"port\": \"80\",\n \"position\": 0,\n \"protocols\": [\n \"TCP\"\n ]\n}]\n\nRetrieve all groups\n\ncurl -X GET -u admin:admin http://localhost:8980/opennms/rest/classifications/groups\n[\"classification\"]: \"Classification rules defined by OpenNMS\", \"enabled\": false, \"id\": 1, \"name\": \"pre-defined\", \"priority\": 0, \"readOnly\": true, \"ruleCount\": 6248 },\n{\"classification\"]: \"Classification rules defined by the user\", \"enabled\": true, \"id\": 2, \"name\": \"user-defined\", \"priority\": 10, \"readOnly\": false, \"ruleCount\": 1\n]}\n\nRetrieve specific rule\n\ncurl -X GET -u admin:admin http://localhost:8980/opennms/rest/classifications/1\n\nResponse\n\n{\n\"group\": {\"classification\"]: \"Classification rules defined by the user\", \"enabled\": true, \"id\": 2, \"name\": \"user-defined\", \"priority\": 10, \"readOnly\": false, \"ruleCount\": 1\n},\n\"id\": 1, \"ipAddress\": null, \"name\": \"http\", \"port\": \"80\", \"position\": 0, \"protocols\": [\"TCP\"\n]}\n\n\nRetrieve specific group\n\ncurl -X GET -H \"Accept: application/json\" -u admin:admin\nhttp://localhost:8980/opennms/rest/classifications/groups/1\n\nResponse\n\n```\n{\n \"description\": \"Classification rules defined by OpenNMS\",\n \"enabled\": false,\n \"id\": 1,\n \"name\": \"pre-defined\",\n \"priority\": 0,\n \"readOnly\": true,\n \"ruleCount\": 6248\n}\n```\n\nRetrieve group as CSV\n\ncurl -X GET -H \"Accept: text/comma-separated-values\" -u admin:admin\nhttp://localhost:8980/opennms/rest/classifications/groups/2\n\nResponse\n\n```\nnname;ipAddress;port;protocol\n http;;80;TCP\n```\n\nPOSTs (Creating Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/classifications</td>\n<td>Post a new rule or import rules from CSV. If multiple rules are imported (to user-defined group) from a CSV file all existing rules are deleted.</td>\n</tr>\n<tr>\n<td>/classifications/classify</td>\n<td>Classify the given request based on all enabled rules.</td>\n</tr>\n</tbody>\n</table>\n\nExamples\n\nCreate a single rule\n\ncurl -X POST -H \"Content-Type: application/json\" -u admin:admin -d '{\"name\": \"http\", \"port\":80,8080\", \"protocols\": [\"tcp\", \"udp\"]}'\nhttp://localhost:8980/opennms/rest/classifications\nResponse\n\nHTTP/1.1 201 Created\nDate: Thu, 08 Feb 2018 14:44:27 GMT\nLocation: http://localhost:8980/opennms/rest/classifications/6616\n\nVerify classification engine (rule exists)\n\ncurl -X POST -H \"Content-Type: application/json\" -u admin:admin -d '{\"protocol\": \"tcp\", \"ipAddress\": \"192.168.0.1\", \"port\": \"80\"}'\nhttp://localhost:8980/opennms/rest/classifications/classify\n\nResponse\n\n{\n \"classification\": \"http\"\n}\n\nVerify classification engine (no rule exists)\n\ncurl -X POST -H \"Content-Type: application/json\" -u admin:admin -d '{\"protocol\": \"tcp\", \"ipAddress\": \"192.168.0.1\", \"port\": \"8980\"}'\nhttp://localhost:8980/opennms/rest/classifications/classify\n\nResponse\n\nHTTP/1.1 204 No Content\n\nImport rules from CSV\n\ncurl -X POST -H \"Content-Type: text/comma-separated-values\" -u admin:admin -d $'name;ipAddress;port;protocol\\nOpenNMS;;8980;tcp,udp\\n'\nhttp://localhost:8980/opennms/rest/classifications/groups/{id}?hasHeader=true\n\nResponse\n\nHTTP/1.1 204 No Content\n\nImport rules from CSV (data with errors)\n\ncurl -X POST -H \"Content-Type: text/comma-separated-values\" -u admin:admin -d $'OpenNMS;;INCORRECT;tcp,udp\\nhttp;;80,8080;ULF'\\nhttp://localhost:8980/opennms/rest/classifications/?hasHeader=false\nResponse\n\n{\n \"errors\": {\n \"1\": {\n \"context\": \"port\",\n \"key\": \"rule.port.definition.invalid\",\n \"message\": \"Please provide a valid port definition. Allowed values are numbers between 0 and 65536. A range can be provided, e.g. \"4000-5000\", multiple values are allowed, e.g. \"80,8080\"\n },\n \"2\": {\n \"context\": \"protocol\",\n \"key\": \"rule.protocol.doesnotexist\",\n \"message\": \"The defined protocol 'ULF' does not exist\"\n }\n },\n \"success\": false\n}\n\nPUTs (Updating Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/classifications/{id}</td>\n<td>Update a rule identified by {id}. The id of the rule cannot be changed.</td>\n</tr>\n<tr>\n<td>/groups/{id}</td>\n<td>Retrieve the rule identified by {id}.</td>\n</tr>\n<tr>\n<td>/classifications/groups</td>\n<td>Update a group. At the moment, only the enabled property can be changed.</td>\n</tr>\n</tbody>\n</table>\n\nDELETEs (Deleting Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/classifications?groupId={groupId}</td>\n<td>Deletes all rules of a given group.</td>\n</tr>\n<tr>\n<td>/groups/{id}</td>\n<td>Delete the given group and all it's containing rules.</td>\n</tr>\n</tbody>\n</table>\n\n6.9.9. Foreign Sources\n\nReSTful service to the OpenNMS Horizon Provisioning Foreign Source definitions. Foreign source definitions are used to control the scanning (service detection) of services for SLA monitoring as well as the data collection settings for physical interfaces (resources).\n\nThis API supports CRUD operations for managing the Provisioner's foreign source definitions. Foreign source definitions are POSTed and will be deployed when the corresponding requisition gets imported/synchronized by Provisiond.\nIf a request says that it gets the \"active\" foreign source, that means it returns the pending foreign source (being edited for deployment) if there is one, otherwise it returns the deployed foreign source.\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/foreignSources</td>\n<td>Get all active foreign sources.</td>\n</tr>\n<tr>\n<td>/foreignSources/default</td>\n<td>Get the active default foreign source.</td>\n</tr>\n<tr>\n<td>/foreignSources/deployed</td>\n<td>Get the list of all deployed (active) foreign sources.</td>\n</tr>\n<tr>\n<td>/foreignSources/deployed/count</td>\n<td>Get the number of deployed foreign sources. (Returns plaintext, rather than XML or JSON.)</td>\n</tr>\n<tr>\n<td>/foreignSources/{name}</td>\n<td>Get the active foreign source named {name}.</td>\n</tr>\n<tr>\n<td>/foreignSources/{name}/detectors</td>\n<td>Get the configured detectors for the foreign source named {name}.</td>\n</tr>\n<tr>\n<td>/foreignSources/{name}/detectors/{detector}</td>\n<td>Get the specified detector for the foreign source named {name}.</td>\n</tr>\n<tr>\n<td>/foreignSources/{name}/policies</td>\n<td>Get the configured policies for the foreign source named {name}.</td>\n</tr>\n<tr>\n<td>/foreignSources/{name}/policies/{policy}</td>\n<td>Get the specified policy for the foreign source named {name}.</td>\n</tr>\n</tbody>\n</table>\n\nPOSTs (Adding Data)\n\nPOST requires XML using application/xml as its Content-Type.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/foreignSources</td>\n<td>Add a foreign source.</td>\n</tr>\n<tr>\n<td>/foreignSources/{name}/detectors</td>\n<td>Add a detector to the named foreign source.</td>\n</tr>\n<tr>\n<td>/foreignSources/{name}/policies</td>\n<td>Add a policy to the named foreign source.</td>\n</tr>\n</tbody>\n</table>\n\nPUTs (Modifying Data)\n\nPUT requires form data using application/x-www-form-urlencoded as a Content-Type.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/foreignSources/{name}</td>\n<td>Modify a foreign source with the given name.</td>\n</tr>\n</tbody>\n</table>\n### DELETEs (Removing Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/foreignSources/{name}</td>\n<td>Delete the named foreign source.</td>\n</tr>\n<tr>\n<td>/foreignSources/{name}/detectors/{detector}</td>\n<td>Delete the specified detector from the named foreign source.</td>\n</tr>\n<tr>\n<td>/foreignSources/{name}/policies/{policy}</td>\n<td>Delete the specified policy from the named foreign source.</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.10. Graph API\n\nThe **Graph API** can be used to read existing graph and graph containers in the system and is an `api/v2` endpoint.\n\nIf not otherwise specified the **Content-Type** of the request and response is `application/json`.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/graphs</td>\n<td>GET</td>\n<td>Retrieves the meta data of all registered graph containers.</td>\n</tr>\n<tr>\n<td>/graphs/{containerId}</td>\n<td>GET</td>\n<td>Retrieve the container identified by <code>{containerId}</code>. Returns a 404 if a Graph Container with <code>{containerId}</code> does not exist.</td>\n</tr>\n<tr>\n<td>/graphs/{containerId}/{namespace}</td>\n<td>GET</td>\n<td>Retrieve the graph with namespace <code>{namespace}</code> from the container <code>{containerId}</code>. Returns a 404 if either the <code>{containerId}</code> does not exist or the container is not containing any graph with namespace <code>{namespace}</code>.</td>\n</tr>\n<tr>\n<td>/graphs/{containerId}/{namespace}</td>\n<td>POST</td>\n<td>Retrieve the view of the graph with namespace <code>{namespace}</code> from the container <code>{containerId}</code>. The body must contain the query to create the view, e.g. <code>{ "semanticZoomLevel": 1, "verticesInFocus": [] }</code> If no <code>semanticZoomLevel</code> is provided, 1 is assumed. If no <code>verticesInFocus</code> is provided, the default focus of the graph is used. Valid values for <code>verticesInFocus</code> are vertex references (namespace:id tuple, e.g. <code>dummy:1</code>).</td>\n</tr>\n</tbody>\n</table>\n\nAt the moment, the context of a search must always be a concrete `namespace` and can never be over all graphs or containers.\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Method</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/graphs/search/suggestions/{namespace}?s={search}</td>\n<td>GET</td>\n<td>Provides suggestions in the context of <code>{namespace}</code> for the input <code>{search}</code>. Each suggestion has the following properties: context: The context of the suggestion, e.g. Node for a node, id: A unique identifier of the representing element of this suggestion, e.g. node id, label: A human readable label, e.g. node label, provider: The source of the suggestion.</td>\n</tr>\n<tr>\n<td>/graphs/search/results/{namespace}?providerId={providerId}&criteria={criteria}&context={context}</td>\n<td>GET</td>\n<td>Resolves a suggestion to actual vertices. The values for <code>{providerId}</code> and <code>{context}</code> are defined in the suggestion. The <code>{criteria}</code> is the <code>{id}</code> property of the suggestion.</td>\n</tr>\n</tbody>\n</table>\n\nThe API allows to query any container and graph via ReST, but in most cases you should only query for a graph view.\n\nExamples\n\nRetrieve all graph container infos\n\n**Request**\n\n\n**Response**\n\n```\n[\n {\n \"description\": \"Displays all defined applications and their calculated states.\",\n \"graphs\": [\n {\n \"description\": \"Displays all defined applications and their calculated states.\",\n \"label\": \"Application Graph\",\n \"namespace\": \"application\"\n }\n ],\n \"id\": \"application\",\n \"label\": \"Application Graph\"\n },\n {\n \"description\": \"Displays the hierarchy of the defined Business Services and their computed operational states.\",\n \"graphs\": [\n {\n \"description\": \"Displays the hierarchy of the defined Business Services and their computed operational states.\",\n \"namespace\": \"application\"\n }\n ],\n \"id\": \"application\",\n \"label\": \"Application Graph\"\n }\n]\n```\nRetrieve graph container ‘bsm’\n\nRequest\n\nResponse\n\n{\n \"description\": \"Displays the hierarchy of the defined Business Services and their computed operational states.\",\n \"graphs\": [\n {\n \"defaultFocus\": {\n \"type\": \"SELECTION\",\n \"vertexIds\": []\n },\n \"description\": \"Displays the hierarchy of the defined Business Services and their computed operational states.\",\n \"edges\": [],\n \"label\": \"Business Service Graph\",\n \"namespace\": \"bsm\",\n \"vertices\": []\n },\n { \"id\": \"bsm\",\n \"label\": \"Business Service Graph\"\n }\n ],\n \"id\": \"bsm\",\n \"label\": \"Business Service Graph\"\n}\n\nRetrieve graph 'layer3-network' in container 'layer3-topology'\n\nRequest\n\ncurl -X GET -u admin:admin http://localhost:8980/opennms/api/v2/graphs/layer3-topology/layer3-network\n\nResponse\n\n{\n \"defaultFocus\": {\n \"type\": \"ALL\",\n \"vertexIds\": [\n { \"id\": \"horizon\",\n \"namespace\": \"layer3-network\"\n },\n { \"id\": \"database\",\n \"namespace\": \"layer3-network\"\n },\n { \"id\": \"r01\",\n \"namespace\": \"layer3-network\"\n },\n { \"id\": \"r03\",\n \"namespace\": \"layer3-network\"\n }\n ]\n }\n}\n\"namespace\": \"layer3-network\",\n\"id\": \"r02\",\n\"namespace\": \"layer3-network\",\n\"id\": \"location-r02\",\n\"namespace\": \"layer3-network\",\n\"id\": \"net-location\",\n\"namespace\": \"layer3-network\",\n\"id\": \"location-r03\",\n\"namespace\": \"layer3-network\",\n\"id\": \"net-central\",\n\"namespace\": \"layer3-network\",\n\"id\": \"location-r01\",\n\"namespace\": \"layer3-network\",\n\"id\": \"minion-01\",\n\"namespace\": \"layer3-network\"\n}\nedges: [\n{\n\"id\": \"layer3-network:database->layer3-network:net-central\",\n\"namespace\": \"layer3-network\",\n\"source\": {\n\"id\": \"database\",\n\"namespace\": \"layer3-network\"\n},\n\"target\": {\n\"id\": \"net-central\",\n\"namespace\": \"layer3-network\"\n}\n},\n{\n\"id\": \"layer3-network:horizon->layer3-network:net-central\",\n\"namespace\": \"layer3-network\",\n\"source\": {\n\"id\": \"horizon\",\n\"namespace\": \"layer3-network\"\n}\n}\n{\n \"target\": {\n \"id\": \"net-central\",\n \"namespace\": \"layer3-network\"\n }\n},\n{\n \"id\": \"layer3-network:location-r01->layer3-network:net-location\",\n \"namespace\": \"layer3-network\",\n \"source\": {\n \"id\": \"location-r01\",\n \"namespace\": \"layer3-network\"\n },\n \"target\": {\n \"id\": \"net-location\",\n \"namespace\": \"layer3-network\"\n }\n},\n{\n \"id\": \"layer3-network:location-r02->layer3-network:net-location\",\n \"namespace\": \"layer3-network\",\n \"source\": {\n \"id\": \"location-r02\",\n \"namespace\": \"layer3-network\"\n },\n \"target\": {\n \"id\": \"net-location\",\n \"namespace\": \"layer3-network\"\n }\n},\n{\n \"id\": \"layer3-network:location-r03->layer3-network:net-location\",\n \"namespace\": \"layer3-network\",\n \"source\": {\n \"id\": \"location-r03\",\n \"namespace\": \"layer3-network\"\n },\n \"target\": {\n \"id\": \"net-location\",\n \"namespace\": \"layer3-network\"\n }\n},\n{\n \"id\": \"layer3-network:minion-01->layer3-network:net-central\",\n \"namespace\": \"layer3-network\",\n \"source\": {\n \"id\": \"minion-01\",\n \"namespace\": \"layer3-network\"\n },\n \"target\": {\n \"id\": \"net-central\",\n \"namespace\": \"layer3-network\" \n }\n}\n\"namespace\": \"layer3-network\"\n}\n},\n{\n\"id\": \"layer3-network:minion-01->layer3-network:net-location\",\n\"namespace\": \"layer3-network\",\n\"source\": {\n \"id\": \"minion-01\",\n \"namespace\": \"layer3-network\"\n},\n\"target\": {\n \"id\": \"net-location\",\n \"namespace\": \"layer3-network\"\n}\n},\n{\n\"id\": \"layer3-network:r01->layer3-network:net-central\",\n\"namespace\": \"layer3-network\",\n\"source\": {\n \"id\": \"r01\",\n \"namespace\": \"layer3-network\"\n},\n\"target\": {\n \"id\": \"net-central\",\n \"namespace\": \"layer3-network\"\n}\n},\n{\n\"id\": \"layer3-network:r02->layer3-network:net-central\",\n\"namespace\": \"layer3-network\",\n\"source\": {\n \"id\": \"r02\",\n \"namespace\": \"layer3-network\"\n},\n\"target\": {\n \"id\": \"net-central\",\n \"namespace\": \"layer3-network\"\n}\n},\n{\n\"id\": \"layer3-network:r03->layer3-network:net-central\",\n\"namespace\": \"layer3-network\",\n\"source\": {\n \"id\": \"r03\",\n \"namespace\": \"layer3-network\"\n},\n\"target\": {\n \"id\": \"net-central\",\n \"namespace\": \"layer3-network\"\n}\n\"enrichment.resolveNodes\": \"true\",\n\"focus-strategy\": \"ALL\",\n\"id\": \"layer3-topology\",\n\"namespace\": \"layer3-network\",\n\"vertex-status-provider\": \"true\",\n\"vertices\": [\n {\n \"foreignID\": \"database\",\n \"foreignSource\": \"opennms-stack\",\n \"iconKey\": \"database\",\n \"id\": \"database\",\n \"label\": \"database\",\n \"namespace\": \"layer3-network\"\n },\n {\n \"foreignID\": \"horizon\",\n \"foreignSource\": \"opennms-stack\",\n \"iconKey\": \"opennms_server\",\n \"id\": \"horizon\",\n \"label\": \"horizon\",\n \"namespace\": \"layer3-network\"\n },\n {\n \"foreignID\": \"location-r01\",\n \"foreignSource\": \"bgp-routers\",\n \"iconKey\": \"server\",\n \"id\": \"location-r01\",\n \"label\": \"location-r01\",\n \"namespace\": \"layer3-network\"\n },\n {\n \"foreignID\": \"location-r02\",\n \"foreignSource\": \"bgp-routers\",\n \"iconKey\": \"server\",\n \"id\": \"location-r02\",\n \"label\": \"location-r02\",\n \"namespace\": \"layer3-network\"\n },\n {\n \"foreignID\": \"location-r03\",\n \"foreignSource\": \"bgp-routers\",\n \"iconKey\": \"server\",\n \"id\": \"location-r03\",\n \"label\": \"location-r03\",\n \"namespace\": \"layer3-network\"\n },\n {\n \"foreignID\": \"minion-01\",\n \"foreignSource\": \"Minions\",\n \"id\": \"minion-01\",\n \"label\": \"minion-01\",\n \"namespace\": \"layer3-network\"\n }\n]\nGet a view of the graph\n\nRequest\n\ncurl -X POST -u admin:admin -H \"Content-Type: application/json\" -d '{\n \"semanticZoomLevel\": 1,\n \"verticesInFocus\": [\"horizon\"]\n}'\nhttp://localhost:8980/opennms/api/v2/graphs/layer3-topology/layer3-network\n{ \n \"edges\": [ \n { \n \"id\": \"layer3-network:horizon->layer3-network:net-central\",\n \"namespace\": \"layer3-network\",\n \"source\": { \n \"id\": \"horizon\",\n \"namespace\": \"layer3-network\"\n },\n \"target\": { \n \"id\": \"net-central\",\n \"namespace\": \"layer3-network\"\n }\n }\n ],\n \"enrichment.resolveNodes\": \"true\",\n \"focus\": { \n \"semanticZoomLevel\": 1,\n \"vertices\": [ \n \"horizon\"\n ]\n },\n \"focus-strategy\": \"ALL\",\n \"id\": \"layer3-topology\",\n \"namespace\": \"layer3-network\",\n \"vertex-status-provider\": \"true\",\n \"vertices\": [ \n { \n \"foreignID\": \"horizon\",\n \"foreignSource\": \"opennms-stack\",\n \"iconKey\": \"opennms_server\",\n \"id\": \"horizon\",\n \"label\": \"horizon\",\n \"namespace\": \"layer3-network\",\n \"nodeInfo\": { \n \"categories\": [],\n \"foreignId\": \"horizon\",\n \"foreignSource\": \"opennms-stack\",\n \"id\": 90,\n \"ipInterfaces\": [ \n { \n \"address\": \"192.168.4.1\",\n \"managed\": true,\n \"primary\": false\n }\n ],\n \"label\": \"horizon\",\n \"location\": \"Default\"\n } \n }\n ]\n}\nSearch Suggestions\n\nRequest\n\ncurl -X GET -u admin:admin\nhttp://localhost:8980/opennms/api/v2/graphs/search/suggestions/layer3-network?s=horizon\n\nResponse\n\n[\n\n{\n\n\"context\": \"GenericVertex\",\n\"id\": \"horizon\",\n\"label\": \"horizon\",\n\"provider\": \"LabelSearchProvider\"\n}\n\n,\n\n{\n\n\"context\": \"Node\",\n\"id\": \"90\",\n\"label\": \"horizon\",\n\"provider\": \"NodeSearchProvider\"\n}\n\n]\n\nSearch Results\n\nRequest\n\ncurl -X GET -u admin:admin\nhttp://localhost:8980/opennms/api/v2/graphs/search/results/layer3-network?providerId=NodeSearchProvider&context=Node&criteria=90\n6.9.11. Groups\n\nLike users, groups have a simplified interface as well.\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/groups</td>\n<td>Get a list of groups.</td>\n</tr>\n<tr>\n<td>/groups/{groupname}</td>\n<td>Get a specific group, given a group name.</td>\n</tr>\n<tr>\n<td>/groups/{groupname}/users</td>\n<td>Get the users for a group, given a group name. (new in OpenNMS 14)</td>\n</tr>\n<tr>\n<td>/groups/{groupname}/categories</td>\n<td>Get the categories associated with a group, given a group name. (new in OpenNMS 14)</td>\n</tr>\n</tbody>\n</table>\n\n**POSTs (Adding Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/groups</td>\n<td>Add a new group.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/groups/{groupname}</td>\n<td>Update the metadata of a group (eg, change the comments field).</td>\n</tr>\n<tr>\n<td>/groups/{groupname}/users/{username}</td>\n<td>Add a user to the group, given a group name and username. (new in OpenNMS 14)</td>\n</tr>\n<tr>\n<td>/groups/{groupname}/categories/{categoryname}</td>\n<td>Associate a category with the group, given a group name and category name. (new in OpenNMS 14)</td>\n</tr>\n</tbody>\n</table>\n\n**DELETEs (Removing Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/groups/{groupname}</td>\n<td>Delete a group.</td>\n</tr>\n<tr>\n<td>Resource</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------------------------------</td>\n<td>-----------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>/groups/{groupname}/users/{username}</td>\n<td>Remove a user from the group. (new in OpenNMS 14)</td>\n</tr>\n<tr>\n<td>/groups/{groupname}/categories/{categoryname}</td>\n<td>Disassociate a category from a group, given a group name and category name. (new in OpenNMS 14)</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.12. Heatmap\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/heatmap/outages/categories</td>\n<td>Sizes and color codes based on outages for nodes grouped by Surveillance Categories</td>\n</tr>\n<tr>\n<td>/heatmap/outages/foreignSources</td>\n<td>Sizes and color codes based on outages for nodes grouped by Foreign Source</td>\n</tr>\n<tr>\n<td>/heatmap/outages/monitoredServices</td>\n<td>Sizes and color codes based on outages for nodes grouped by monitored services</td>\n</tr>\n<tr>\n<td>/heatmap/outages/nodesByCategory/{category}</td>\n<td>Sizes and color codes based on outages for nodes associated with a specific Surveillance Category</td>\n</tr>\n<tr>\n<td>/heatmap/outages/nodesByForeignSource/{foreignSource}</td>\n<td>Sizes and color codes based on outages for nodes associated with a specific Foreign Source</td>\n</tr>\n<tr>\n<td>/heatmap/outages/nodesByMonitoredService/{monitoredService}</td>\n<td>Sizes and color codes based on outages for nodes providing a specific monitored service</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/heatmap/alarms/categories</td>\n<td>Sizes and color codes based on alarms for nodes grouped by Surveillance Categories</td>\n</tr>\n<tr>\n<td>/heatmap/alarms/foreignSources</td>\n<td>Sizes and color codes based on alarms for nodes grouped by Foreign Source</td>\n</tr>\n<tr>\n<td>/heatmap/alarms/monitoredServices</td>\n<td>Sizes and color codes based on alarms for nodes grouped by monitored services</td>\n</tr>\n<tr>\n<td>/heatmap/alarms/nodesByCategory/{category}</td>\n<td>Sizes and color codes based on alarms for nodes associated with a specific Surveillance Category</td>\n</tr>\n<tr>\n<td>/heatmap/alarms/nodesByForeignSource/{foreignSource}</td>\n<td>Sizes and color codes based on alarms for nodes associated with a specific Foreign Source</td>\n</tr>\n<tr>\n<td>/heatmap/alarms/nodesByMonitoredService/{monitoredService}</td>\n<td>Sizes and color codes based on alarms for nodes providing a specific monitored service</td>\n</tr>\n</tbody>\n</table>\n6.9.13. Monitored Services\n\nObtain or modify the status of a set of monitored services based on a given search criteria, based on nodes, IP interfaces, Categories, or monitored services itself.\n\nExamples:\n\n- `/ifservices?node.label=onms-prd-01`\n- `/ifservices?ipInterface.ipAddress=192.168.32.140`\n- `/ifservices?category.name=Production`\n- `/ifservices?status=A`\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/ifservices</td>\n<td>Get all configured monitored services for the given search criteria.</td>\n</tr>\n</tbody>\n</table>\n\nExample:\n\nGet the forced unmanaged services for the nodes that belong to the requisition named Servers:\n\n```\n```\n\nPUTs (Modifying Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/ifservices/</td>\n<td>Update all configured monitored services for the given search criteria.</td>\n</tr>\n</tbody>\n</table>\n\nExample:\n\nMark the ICMP and HTTP services to be forced unmanaged for the nodes that belong to the category Production:\n\n```\ncurl -u admin:admin -X PUT \"status=F&services=ICMP,HTTP\" \n\"http://localhost:8980/opennms/rest/ifservices?category.name=Production\"\n```\n\n6.9.14. IP Interfaces\n\nObtain a list of IP interfaces based on a set of criteria.\n\n- This API is v2-only, and uses FIQL for querying.\nExamples:\n\n- `/api/v2/ipinterfaces?_s=node.label==onms-prd-01`\n- `/api/v2/ipinterfaces?_s=ipAddress==192.168.32.140`\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/ipinterfaces</td>\n<td>Get all IP interfaces for the given search criteria.</td>\n</tr>\n</tbody>\n</table>\n\nExample:\n\nGet IP interfaces whose node are in the foreign source Servers:\n\n```bash\ncurl -u admin:admin \"http://localhost:8980/opennms/api/v2/ipinterfaces?_s=node.foreignSource==Servers\"\n```\n\nPUTs/POSTs (Modifying Data)\n\nThe `/ipinterfaces` ReST API is read-only. If you wish to create new IP interfaces, use the `ipinterfaces` resources under the `nodes` endpoint.\n\n6.9.15. KSC Reports\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/ksc</td>\n<td>Get a list of all KSC reports, this includes ID and label.</td>\n</tr>\n<tr>\n<td>/ksc/{reportId}</td>\n<td>Get a specific KSC report, by ID.</td>\n</tr>\n<tr>\n<td>/ksc/count</td>\n<td>Get a count of all KSC reports.</td>\n</tr>\n</tbody>\n</table>\n\nPUTs (Modifying Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/ksc/{reportId}</td>\n<td>Modify a report with the given ID.</td>\n</tr>\n</tbody>\n</table>\n\nPOSTs (Creating Data)\n\nDocumentation incomplete see issue: NMS-7162\n\nDELETEs (Removing Data)\n\nDocumentation incomplete see issue: NMS-7162\n6.9.16. Maps\n\nThe SVG maps use ReST to populate their data. This is the interface for doing that.\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/maps</td>\n<td>Get the list of maps.</td>\n</tr>\n<tr>\n<td>/maps/{id}</td>\n<td>Get the map with the given ID.</td>\n</tr>\n<tr>\n<td>/maps/{id}/mapElements</td>\n<td>Get the elements (<em>nodes, links, etc.</em>) for the map with the given ID.</td>\n</tr>\n</tbody>\n</table>\n\n**POSTs (Adding Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/maps</td>\n<td>Add a map.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/maps/{id}</td>\n<td>Update the properties of the map with the given ID.</td>\n</tr>\n</tbody>\n</table>\n\n**DELETEs (Removing Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/maps/{id}</td>\n<td>Delete the map with the given ID.</td>\n</tr>\n</tbody>\n</table>\n\n6.9.17. Measurements API\n\nThe Measurements API can be used to retrieve collected values stored in RRD (or JRB) files and in Newts.\n\nUnless specific otherwise, all unit of time are expressed in milliseconds.\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/measurements/{resourceId}/{attribute}</td>\n<td>Retrieve the measurements for a single attribute</td>\n</tr>\n</tbody>\n</table>\n\nThe following table shows all supported query string parameters and their default values.\n<table>\n<thead>\n<tr>\n<th>name</th>\n<th>default</th>\n<th>comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>start</td>\n<td>-14400000</td>\n<td>Timestamp in milliseconds. If > 0, the timestamp is relative to the UNIX epoch (January 1st 1970 00:00:00 AM). If < 0, the timestamp is relative to the <code>end</code> option (i.e.: default value is 4 hours ago).</td>\n</tr>\n<tr>\n<td>end</td>\n<td>0</td>\n<td>Timestamp in milliseconds. If <= 0, the effective value will be the current timestamp.</td>\n</tr>\n<tr>\n<td>step</td>\n<td>300000</td>\n<td>Requested time interval between rows. Actual step may differ.</td>\n</tr>\n<tr>\n<td>maxrows</td>\n<td>0</td>\n<td>When using the measurements to render a graph, this should be set to the graph’s pixel width.</td>\n</tr>\n<tr>\n<td>aggregation</td>\n<td>AVERAGE</td>\n<td>Consolidation function used. Can typically be <code>AVERAGE</code>, <code>MIN</code> or <code>MAX</code>. Depends on <code>RRA</code> definitions.</td>\n</tr>\n<tr>\n<td>fallback-attribute</td>\n<td></td>\n<td>Secondary attribute that will be queried in the case the primary attribute does not exist.</td>\n</tr>\n</tbody>\n</table>\n\n**Step sizes**\n\nThe behavior of the `step` parameter changes based on time series strategy that is being used.\n\nWhen using persistence strategies based on `RRD`, the available step sizes are limited to those defined by the `RRA` when the file was created. The effective step size used will be one that covers the requested period, and is closest to the requested step size. For maximum accuracy, use a step size of 1.\n\nWhen using Newts, the step size can be set arbitrarily since the aggregation is performed at the time of request. In order to help prevent large requests, we limit to the step size of a minimum of 5 minutes, the default collection rate. This value can be decreased by setting the `org.opennms.newts.query.minimum_step` system property.\n\n**Usage examples with curl**\nRetrieve CPU counter metrics over the last 2 hours for node 1\n\ncurl -u admin:admin\n\"http://127.0.0.1:8980/opennms/rest/measurements/node%5B1%5D.nodeSnmp%5B%5D/CpuRawUser\n?start=-7200000&maxrows=30&aggregation=AVERAGE\"\n\nResponse\n\n<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?><query-response end=\"1425588138256\" start=\"1425580938256\" step=\"300000\">\n <columns>\n <values>159.5957271523179</values>\n <values>158.08531037527592</values>\n <values>158.45835584842285</values>\n ...\n </columns>\n <labels>CpuRawUser</labels>\n <metadata>\n <resources>...\n </resources>\n <nodes>...\n </nodes>\n </metadata>\n <timestamps>1425581100000</timestamps>\n <timestamps>1425581400000</timestamps>\n <timestamps>1425581700000</timestamps>\n ...\n</query-response>\n\nPOSTs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/measurements</td>\n<td>Retrieve the measurements for one or more attributes, possibly spanning multiple resources, with support for JEXL expressions.</td>\n</tr>\n</tbody>\n</table>\n\nHere we use a POST instead of a GET to retrieve the measurements, which allows us to perform complex queries which are difficult to express in a query string. These requests cannot be used to update or create new metrics.\n\nAn example of the POST body is available below.\n\nUsage examples with curl\nRetrieve bits in and bits out metrics for a particular interface. Perform calculations on bits out, and only return the derived values.\n\n```\ncurl -X POST -H \"Accept: application/json\" -H \"Content-Type: application/json\" -u admin:admin -d @report.json http://127.0.0.1:8980/opennms/rest/measurements\n```\n\nContents of report.json\n\n```json\n{\n \"start\": 1425563626316,\n \"end\": 1425585226316,\n \"step\": 10000,\n \"maxrows\": 1600,\n \"source\": [\n {\n \"aggregation\": \"AVERAGE\",\n \"attribute\": \"ifHCInOctets\",\n \"label\": \"ifHCInOctets\",\n \"resourceId\": \"nodeSource[Servers:1424038123222].interfaceSnmp[eth0-04013f75f101]\",\n \"transient\": \"false\"\n },\n {\n \"aggregation\": \"AVERAGE\",\n \"attribute\": \"ifHCOutOctets\",\n \"label\": \"ifHCOutOctets\",\n \"resourceId\": \"nodeSource[ Servers:1424038123222].interfaceSnmp [ eth0-04013f75f101]\",\n \"transient\": \"true\"\n }\n ],\n \"expression\": [\n {\n \"label\": \"ifHCOutOctetsNeg\",\n \"value\": \"-1.0 * ifHCOutOctets\",\n \"transient\": \"false\"\n }\n ]\n}\n```\n\nResponse\n\n```json\n{\n \"step\": 300000,\n \"start\": 1425563626316,\n \"end\": 1425585226316,\n \"timestamps\": [\n 1425563700000,\n 1425564000000,\n 1425564300000,\n ]\n}\n```\n\"labels\": [\n \"ifHCInOctets\",\n \"ifHCOutOctetsNeg\"\n],\n\"columns\": [\n {\"values\": [\n 139.94817275747508,\n 199.0062569213732,\n 162.6264894795127,\n ...\n ]},\n {\"values\": [\n -151.66179401993355,\n -214.7415503875969,\n -184.9012624584718,\n ...\n ]}\n],\n\"metadata\": {\n \"resources\": [\n {\n \"id\": \"nodeSource[ Servers: 1424038123222]. interfaceSnmp[ eth0-04013f75f101]\",\n \"label\": \"eth0-04013f75f101\",\n \"name\": \"eth0-04013f75f101\",\n \"parent-id\": \"nodeSource[ Servers: 1424038123222]\",\n \"node-id\": 1\n },\n {\n \"id\": \"nodeSource[ Servers: 1424038123222]. interfaceSnmp[ eth0-04013f75f101]\",\n \"label\": \"eth0-04013f75f101\",\n \"name\": \"eth0-04013f75f101\",\n \"parent-id\": \"nodeSource[ Servers: 1424038123222]\",\n \"node-id\": 1\n }\n ],\n \"nodes\": [\n {\n \"id\": 1,\n \"label\": \"Test Server\",\n \"foreign-source\": \"Servers\",\n \"foreign-id\": \"1424038123222\"\n }\n ]}\nMore Advanced Expressions\n\nThe JEXL 2.1.x library is used to parse the expression string and this also allows java objects and predefined functions to be included in the expression.\n\nJEXL uses a context which is pre-populated by OpenNMS with the results of the query. Several constants and arrays are also predefined as references in the context by OpenNMS.\n\n<table>\n<thead>\n<tr>\n<th>Constant or prefix</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>__inf</td>\n<td>Double.POSITIVE_INFINITY</td>\n</tr>\n<tr>\n<td>__neg_inf</td>\n<td>Double.NEGATIVE_INFINITY</td>\n</tr>\n<tr>\n<td>NaN</td>\n<td>Double.NaN</td>\n</tr>\n<tr>\n<td>__E</td>\n<td>java.lang.Math.E</td>\n</tr>\n<tr>\n<td>__PI</td>\n<td>java.lang.Math.PI</td>\n</tr>\n<tr>\n<td>__diff_time</td>\n<td>Time span between start and end of samples</td>\n</tr>\n<tr>\n<td>__step</td>\n<td>Difference in time between subsequent values</td>\n</tr>\n<tr>\n<td>__i</td>\n<td>Index into the samples array which the present calculation is referencing</td>\n</tr>\n<tr>\n<td>__AttributeName (where AttributeName is the searched for attribute)</td>\n<td>This returns the complete double[] array of samples for AttributeName</td>\n</tr>\n</tbody>\n</table>\n\nOpenNMS predefines a number of functions for use in expressions which are referenced by namespace:function. All of these functions return a java double value.\n\nPre defined functions\n<table>\n<thead>\n<tr>\n<th>Function</th>\n<th>Description</th>\n<th>Example</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>jexl:evaluate("_formula")</td>\n<td>Passes a string to the JEXL engine to be evaluated as if it was entered as a normal expression. Like normal expressions, expressions evaluated through this function will return a Java double value. This makes it possible to reference and evaluate a formula which has been stored in OpenNMS as a string variable. The use case for this capability is that it gives us the ability to define and store a per-node and per-value correction formula which can normalise samples from different sample sources.</td>\n<td></td>\n</tr>\n<tr>\n<td>math:</td>\n<td>References java.lang.Math class</td>\n<td>math:cos(20)</td>\n</tr>\n<tr>\n<td>strictmath:</td>\n<td>References java.lang.StrictMath class</td>\n<td>math:cos(20)</td>\n</tr>\n<tr>\n<td>fn:</td>\n<td>References the class org.opennms.netmgt.measurements.impl.SampleArrayFunctions. This contains several functions which can reference previous samples in the time series.</td>\n<td></td>\n</tr>\n<tr>\n<td>fn:arrayNaN("sampleName", n)</td>\n<td>References the nth previous sample in the "sampleName" sample series. Replacing the n samples before the start of the series with NaN.</td>\n<td>fn:arrayNaN("x", 5)</td>\n</tr>\n<tr>\n<td>fn:arrayZero("sampleName", n)</td>\n<td>References the nth previous sample in the "sampleName" sample series. Replacing the n samples before the start of the series with 0 (zero).</td>\n<td>fn:arrayZero("x", 5)</td>\n</tr>\n<tr>\n<td>Function</td>\n<td>Description</td>\n<td>Example</td>\n</tr>\n<tr>\n<td>-----------------------------------------------</td>\n<td>------------------------------------------------------------------------------</td>\n<td>--------------------------</td>\n</tr>\n<tr>\n<td>fn:arrayFirst("sampleName", n)</td>\n<td>References the nth previous sample in the "sampleName" sample series. Replacing the n samples before the start of the series with the first sample.</td>\n<td>fn:arrayFirst("x", 5)</td>\n</tr>\n<tr>\n<td>fn:arrayStart("sampleName", n, constant)</td>\n<td>References the nth previous sample in the "sampleName" sample series. Replacing the n samples before the start of the series with a supplied constant.</td>\n<td>fn:arrayStart("x", 5, 10)</td>\n</tr>\n</tbody>\n</table>\n\nSo for example with these additional variables and functions it is possible to create a Finite Impulse Response (FIR) filter function such as\n\n\\[ y = a \\times f(n) + b \\times f(n-1) + c \\times f(n-2) \\]\n\nusing the following expression where a, b and c are string constants and x is a time series value\n\n\\[ a \\times x + b \\times \\text{fn:arrayNaN}(\"x\", 1) + c \\times \\text{fn:arrayNaN}(\"x\", 2) \\]\n\n### 6.9.18. Meta-Data\n\nThe actual Meta-Data of nodes, interfaces and services can be queried, added, modified or deleted via ReST endpoints.\n\n**GETs (Reading Meta-Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>api/v2/nodes/{id}/metadata</td>\n<td>Get the list of meta-data associated with this node.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/metadata/{context}</td>\n<td>Get the list of meta-data associated with this node filtered by the given context.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/metadata/{context}/{key}</td>\n<td>Get the entry for the given context and key associated with this node.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/ipinterfaces/{ipInterface}/metadata</td>\n<td>Get the list of meta-data associated with this interface.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/ipinterfaces/{ipInterface}/metadata/{context}</td>\n<td>Get the list of meta-data associated with this interface filtered by the given context.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/ipinterfaces/{ipInterface}/metadata/{context}/{key}</td>\n<td>Get the entry for the given context and key associated with this interface.</td>\n</tr>\n<tr>\n<td>Resource</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>------------------------------------------------------------------------</td>\n<td>------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/ipinterfaces/{ipInterface}/services/{service}/metadata</td>\n<td>Get the list of meta-data associated with this service.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/ipinterfaces/{ipInterface}/services/{service}/metadata/{context}</td>\n<td>Get the list of meta-data associated with this service filtered by the given context.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/ipinterfaces/{ipInterface}/services/{service}/metadata/{context}/{key}</td>\n<td>Get the entry for the given context and key associated with this service.</td>\n</tr>\n</tbody>\n</table>\n\n**POSTs (Adding Meta-Data)**\n\nPOST requires XML using application/xml as its Content-Type.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>api/v2/nodes/{id}/metadata</td>\n<td>Adds a meta-data entry to the given node.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/{ipInterface}/metadata</td>\n<td>Adds a meta-data entry to the given interface.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/{ipInterface}/services/{service}/metadata</td>\n<td>Adds a meta-data entry to the given service.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Meta-Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>api/v2/nodes/{id}/metadata/{context}/{key}/{value}</td>\n<td>Sets the given value for the node-level meta-data entry specified by the given context and key.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/ipinterfaces/{ipInterface}/metadata/{context}/{key}/{value}</td>\n<td>Sets the given value for the interface-level meta-data entry specified by the given context and key.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/ipinterfaces/{ipInterface}/services/{service}/metadata/{context}/{key}/{value}</td>\n<td>Sets the given value for the service-level meta-data entry specified by the given context and key.</td>\n</tr>\n</tbody>\n</table>\n\n**DELETEs (Removing Meta-Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>api/v2/nodes/{id}/metadata/{context}</td>\n<td>Deletes node-level meta-data with the given context.</td>\n</tr>\n<tr>\n<td>api/v2/nodes/{id}/metadata/{context}/{key}</td>\n<td>Deletes the node-level meta-data entry for the given context and key.</td>\n</tr>\n</tbody>\n</table>\n### 6.9.19. Nodes\n\nNote: the default offset is 0, the default limit is 10 results. To get all results, use limit=0 as a parameter on the URL (ie, GET /nodes?limit=0).\n\nAdditionally, anywhere you use \"id\" in the queries below, you can use the foreign source and foreign ID separated by a colon instead (ie, GET /nodes/fs:fid).\n\n#### GETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/nodes</td>\n<td>Get a list of nodes. This includes the ID and node label.</td>\n</tr>\n<tr>\n<td>/nodes/{id}</td>\n<td>Get a specific node, by ID.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/ipinterfaces</td>\n<td>Get the list of IP interfaces associated with the given node.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/ipinterfaces/{ipAddress}</td>\n<td>Get the IP interface for the given node and IP address.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/ipinterfaces/{ipAddress}/services</td>\n<td>Get the list of services associated with the given node and IP interface.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/ipinterfaces/{ipAddress}/services/{service}</td>\n<td>Get the requested service associated with the given node, IP interface, and service name.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/snmpinterfaces</td>\n<td>Get the list of SNMP interfaces associated with the given node.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/snmpinterfaces/{ifIndex}</td>\n<td>Get the specific interface associated with the given node and ifIndex.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/categories</td>\n<td>Get the list of categories associated with the given node.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/categories/{categoryName}</td>\n<td>Get the category associated with the given node and category name.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/assetRecord</td>\n<td>Get the asset record associated with the given node.</td>\n</tr>\n</tbody>\n</table>\nPOSTs (Adding Data)\n\nPOST requires XML using application/xml as its Content-Type.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/nodes</td>\n<td>Add a node.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/ipinterfaces</td>\n<td>Add an IP interface to the node.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/ipinterfaces/{ipAddress}/services</td>\n<td>Add a service to the interface for the given node.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/snmpinterfaces</td>\n<td>Add an SNMP interface to the node.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/categories</td>\n<td>Add a category association to the node.</td>\n</tr>\n</tbody>\n</table>\n\nPUTs (Modifying Data)\n\nPUT requires form data using application/x-www-form-urlencoded as a Content-Type.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/nodes/{id}</td>\n<td>Modify a node with the given ID.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/ipinterfaces/{ipAddress}</td>\n<td>Modify the IP interface with the given node ID and IP address.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/ipinterfaces/{ipAddress}/services/{service}</td>\n<td>Modify the service with the given node ID, IP address, and service name.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/snmpinterfaces/{ifIndex}</td>\n<td>Modify the SNMP interface with the given node ID and ifIndex.</td>\n</tr>\n<tr>\n<td>/nodes/{id}/categories/{categoryName}</td>\n<td>Modify the category with the given node ID and name.</td>\n</tr>\n</tbody>\n</table>\n\nDELETEs (Removing Data)\n\nPerform a DELETE to the singleton URLs specified in PUT above to delete that object.\n\nDeletion of nodes, ipinterfaces and services are asynchronous so they will return 202 (ACCEPTED). Deletion of snmpinterfaces and categories are synchronous calls so they will return 204 (NO_CONTENT) on success.\n\n6.9.20. Notifications\n\nNote: the default offset is 0, the default limit is 10 results. To get all results, use limit=0 as a parameter on the URL (ie, GET /events?limit=0).\n\nGETs (Reading Data)\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/notifications</td>\n<td>Get a list of notifications.</td>\n</tr>\n<tr>\n<td>/notifications/count</td>\n<td>Get the number of notifications. (Returns plaintext, rather than XML or JSON.)</td>\n</tr>\n<tr>\n<td>/notifications/{id}</td>\n<td>Get the notification specified by the given ID.</td>\n</tr>\n</tbody>\n</table>\n\nTo acknowledge or unacknowledge a notification, use the **acks** endpoint — see Acknowledgements.\n\n### 6.9.21. Outage Timelines\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/header/{start}/{end}/{width}</td>\n<td>Generate the timeline header</td>\n</tr>\n<tr>\n<td>/image/{nodeId}/{ipAddress}/{serviceName}/{start}/{end}/{width}</td>\n<td>Generate the timeline image</td>\n</tr>\n<tr>\n<td>/empty/{start}/{end}/{width}</td>\n<td>Generate an empty timeline for non-monitored services</td>\n</tr>\n<tr>\n<td>/html/{nodeId}/{ipAddress}/{serviceName}/{start}/{end}/{width}</td>\n<td>Generate the raw HTML for the image</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.22. Outages\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/outages</td>\n<td>Get a list of outages.</td>\n</tr>\n<tr>\n<td>/outages/count</td>\n<td>Get the number of outages. (Returns plaintext, rather than XML or JSON.)</td>\n</tr>\n<tr>\n<td>/outages/{id}</td>\n<td>Get the outage specified by the given ID.</td>\n</tr>\n<tr>\n<td>/outages/forNode/{nodeId}</td>\n<td>Get the outages that match the given node ID.</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.23. Requisitions\n\nRESTful service to the OpenNMS Horizon Provisioning Requisitions. In this API, these “groups” of nodes are aptly named and treated as requisitions.\n\nThis current implementation supports **CRUD** operations for managing provisioning requisitions. Requisitions are first POSTed and no provisioning (import/synchronize) operations are taken. This is done so that a) the XML can be verified and b) so that the operations can happen at a later time.\nThey are moved to the deployed state (put in the active requisition repository) when an import is run.\n\nIf a request says that it gets the active requisition, that means it returns the pending requisition (being edited for deployment) if there is one, otherwise it returns the deployed requisition. Note that anything that says it adds/deletes/modifies a node, interface, etc. in these instructions is referring to modifying that element from the requisition not from the database itself. That will happen upon import/synchronization.\n\nYou may write requisition data if the authenticated user is in the provision, rest, or admin roles.\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/requisitions</td>\n<td>Get all active requisitions.</td>\n</tr>\n<tr>\n<td>/requisitions/count</td>\n<td>Get the number of active requisitions. (Returns plaintext, rather than XML or JSON.)</td>\n</tr>\n<tr>\n<td>/requisitions/deployed</td>\n<td>Get the list of all deployed (active) requisitions.</td>\n</tr>\n<tr>\n<td>/requisitions/deployed/count</td>\n<td>Get the number of deployed requisitions. (Returns plaintext, rather than XML or JSON.)</td>\n</tr>\n<tr>\n<td>/requisitions/{name}</td>\n<td>Get the active requisition for the given foreign source name.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes</td>\n<td>Get the list of nodes being requisitioned for the given foreign source name.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}</td>\n<td>Get the node with the given foreign ID for the given foreign source name.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/interfaces</td>\n<td>Get the interfaces for the node with the given foreign ID and foreign source name.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/interfaces/{ipAddress}</td>\n<td>Get the interface with the given IP for the node with the specified foreign ID and foreign source name.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/interfaces/{ipAddress}/services</td>\n<td>Get the services for the interface with the specified IP address, foreign ID, and foreign source name.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/interfaces/{ipAddress}/services/{service}</td>\n<td>Get the given service with the specified IP address, foreign ID, and foreign source name.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/categories</td>\n<td>Get the categories for the node with the given foreign ID and foreign source name.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/categories/{categoryName}</td>\n<td>Get the category with the given name for the node with the specified foreign ID and foreign source name.</td>\n</tr>\n<tr>\n<td>Resource</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/assets</td>\n<td>Get the assets for the node with the given foreign ID and foreign source name.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/assets/{assetName}</td>\n<td>Get the value of the asset for the given assetName for the node with the given foreign ID and foreign source name.</td>\n</tr>\n</tbody>\n</table>\n\n**POSTs (Adding Data or Updating existing Data)**\n\n- Expects JSON/XML\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/requisitions</td>\n<td>Adds (or replaces) a requisition.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes</td>\n<td>Adds (or replaces) a node in the specified requisition. This operation can be very helpful when working with [[Large Requisitions]].</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/interfaces</td>\n<td>Adds (or replaces) an interface for the given node in the specified requisition.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/interfaces/{ipAddress}/services</td>\n<td>Adds (or replaces) a service on the given interface in the specified requisition.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/categories</td>\n<td>Adds (or replaces) a category for the given node in the specified requisition.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/assets</td>\n<td>Adds (or replaces) an asset for the given node in the specified requisition.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Data)**\n\n- Expects form-urlencoded\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/requisitions/{name}/import</td>\n<td>Performs an import/synchronize on the specified foreign source. This turns the "active" requisition into the "deployed" requisition.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/import?rescanExisting=false</td>\n<td>Performs an import/synchronize on the specified foreign source. This turns the "active" requisition into the "deployed" requisition. Existing nodes will not be scanned until the next rescan interval, only newly-added nodes will be. Useful if you're planning on making a series of changes.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}</td>\n<td>Update the specified foreign source.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}</td>\n<td>Update the specified node for the given foreign source.</td>\n</tr>\n<tr>\n<td>Resource</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/interfaces/{ipAddress}</td>\n<td>Update the specified IP address for the given node and foreign source.</td>\n</tr>\n</tbody>\n</table>\n\n**DELETEs (Removing Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/requisitions/{name}</td>\n<td>Delete the pending requisition for the named foreign source.</td>\n</tr>\n<tr>\n<td>/requisitions/deployed/{name}</td>\n<td>Delete the active requisition for the named foreign source.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}</td>\n<td>Delete the node with the given foreign ID from the given requisition.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/interfaces/{ipAddress}</td>\n<td>Delete the IP address from the requisitioned node with the given foreign ID and foreign source.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/interfaces/{ipAddress}/services/{service}</td>\n<td>Delete the service from the requisitioned interface with the given IP address, foreign ID and foreign source.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/categories/{category}</td>\n<td>Delete the category from the node with the given foreign ID and foreign source.</td>\n</tr>\n<tr>\n<td>/requisitions/{name}/nodes/{foreignId}/assets/{field}</td>\n<td>Delete the field from the requisition’s nodes asset with the given foreign ID and foreign source.</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.24. Resources API\n\nThe Resources API can be used to list or delete resources at the node level and below. This service is especially useful in conjunction with the Measurements API.\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/resources</td>\n<td>Retrieve the full tree of resources in the system (expensive, use with care)</td>\n</tr>\n<tr>\n<td>/resources/{resourceId}</td>\n<td>Retrieve the tree of resources starting with the named resource ID</td>\n</tr>\n<tr>\n<td>/resources/fornode/{nodeCriteria}</td>\n<td>Retrieve the tree of resources for a node, given its database ID or foreign-source:foreign-ID tuple</td>\n</tr>\n</tbody>\n</table>\n\n**DELETEs (Removing Data)**\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/resources/{resourceId}</td>\n<td>Delete resource with the named resource ID, and all its child resources, if any</td>\n</tr>\n</tbody>\n</table>\n\nThe following table shows all supported query string parameters and their default values.\n\n<table>\n<thead>\n<tr>\n<th>name</th>\n<th>default</th>\n<th>comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>depth</td>\n<td>varies</td>\n<td>GET only. Limits the tree depth for retrieved resources. Defaults to 1 when listing all resources, or to -1 (no limit) when listing a single resource.</td>\n</tr>\n</tbody>\n</table>\n\n**Usage examples with curl**\n\n*Retrieve the tree of resources rooted at the node with database ID 1, by resource ID*\n\n```bash\ncurl -u admin:admin \"http://127.0.0.1:8980/opennms/rest/resources/node%5B1%5D\"\n```\n\n**Response**\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n<resource id=\"node[1]\"\n label=\"anode\"\n name=\"1\"\n link=\"element/node.jsp?node=1\"\n typeLabel=\"Node\">\n <children count=\"11\" totalCount=\"11\">\n <resource id=\"node[1].nodeSnmp[]\"\n label=\"Node-level Performance Data\"\n name=\"\"\n typeLabel=\"SNMP Node Data\"\n parentId=\"node[1]\">\n </resource>\n </children>\n <stringPropertyAttributes/>\n <externalValueAttributes/>\n <rrdGraphAttributes>\n <entry>\n <key>loadavg1</key>\n <value name=\"loadavg1\"\n relativePath=\"snmp/1\"\n rrdFile=\"loadavg1.jrb\"/>\n </entry>\n <key(tcpActiveOpens></key>\n <value name=\"tcpActiveOpens\"\n relativePath=\"snmp/1\"\n rrdFile=\"tcpActiveOpens.jrb\"/>\n </entry>\n```\n<entry>\n <key>memTotalFree</key>\n <value name=\"memTotalFree\"\n relativePath=\"snmp/1\"\n rrdFile=\"memTotalFree.jrb\"/>\n</entry>\n...\n</rrdGraphAttributes>\n</resource>\n<br>\n<resource id=\"node[1].interfaceSnmp[lo]\"\n label=\"lo (10 Mbps)\"\n name=\"lo\"\n link=\"element/snmpinterface.jsp?node=1&ifindex=1\"\n typeLabel=\"SNMP Interface Data\"\n parentId=\"node[1]\">\n <children/>\n <stringPropertyAttributes>\n <entry>\n <key>ifName</key>\n <value>lo</value>\n </entry>\n ...\n </stringPropertyAttributes>\n <externalValueAttributes>\n <entry>\n <key>ifSpeed</key>\n <value>10000000</value>\n </entry>\n <entry>\n <key>ifSpeedFriendly</key>\n <value>10 Mbps</value>\n </entry>\n ...\n </externalValueAttributes>\n <rrdGraphAttributes>\n ...\n <entry>\n <key>ifHCInOctets</key>\n <value name=\"ifHCInOctets\"\n relativePath=\"snmp/1/lo\"\n rrdFile=\"ifHCInOctets.jrb\"/>\n </entry>\n <entry>\n <key>ifHCOutOctets</key>\n <value name=\"ifHCOutOctets\"\n relativePath=\"snmp/1/lo\"\n rrdFile=\"ifHCOutOctets.jrb\"/>\n </entry>\n ...\n </rrdGraphAttributes>\n</resource>\n...\nRetrieve the tree of resources rooted at the node with database ID 1, without having to construct a resource ID\n\ncurl -u admin:admin \"http://127.0.0.1:8980/opennms/rest/resources/fornode/1\"\n\nRetrieve the tree of resources rooted at the node with foreign-ID node42 in requisition Servers, by resource ID\n\ncurl -u admin:admin\n\"http://127.0.0.1:8980/opennms/rest/resources/nodeSource%5BServers:node42%5D\"\n\nRetrieve the tree of resources rooted at the node with foreign-ID node42 in requisition Servers, without having to construct a resource ID\n\ncurl -u admin:admin\n\"http://127.0.0.1:8980/opennms/rest/resources/fornode/Servers:node42\"\n\n6.9.25. Realtime Console data\n\nThe Realtime Console (RTC) calculates the availability for monitored services. Data provided from the RTC is available to the ReST API.\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/availability/categories/{category}</td>\n<td>Get all nodes and availability data from a given SLA category filter, i.e. Web Servers (Web+Servers)</td>\n</tr>\n<tr>\n<td>/availability/categories/{category}/nodes</td>\n<td>Get node availability data for each node of a given SLA category filter</td>\n</tr>\n<tr>\n<td>/availability/categories/{category}/nodes/{nodeId}</td>\n<td>Get detailed service availability for a given node in a given SLA category filter</td>\n</tr>\n<tr>\n<td>/availability/nodes/{nodeId}</td>\n<td>Get detailed availability for all services on a given node</td>\n</tr>\n</tbody>\n</table>\n\nExample\ncurl -u demo:demo\nhttp://demo.opennms.org/opennms/rest/availability/categories/Web+Servers\n\ncurl -u demo:demo http://demo.opennms.org/opennms/rest/availability/categories/nodes\n\ncurl -u demo:demo http://demo.opennms.org/opennms/rest/availability/categories/nodes/31\n\ncurl -u demo:demo http://demo.opennms.org/opennms/rest/availability/nodes/31\n\n6.9.26. Scheduled Outages\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/sched-outages</td>\n<td>to get a list of configured scheduled outages.</td>\n</tr>\n<tr>\n<td>/sched-outages/{outagename}</td>\n<td>to get the details of a specific outage.</td>\n</tr>\n</tbody>\n</table>\n\nPOSTs (Setting Data)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/sched-outages</td>\n<td>to add a new outage (or update an existing one).</td>\n</tr>\n</tbody>\n</table>\n\nPUTs (Modifying Data)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/sched-outages/{outagename}/collectd/{package}</td>\n<td>to add a specific outage to a collectd’s package.</td>\n</tr>\n<tr>\n<td>/sched-outages/{outagename}/pollerd/{package}</td>\n<td>to add a specific outage to a pollerd’s package.</td>\n</tr>\n</tbody>\n</table>\n### Parameters\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>/sched-outages/{outageName}/threshd/{package}</code></td>\n<td>to add a specific outage to a threshd’s package.</td>\n</tr>\n<tr>\n<td><code>/sched-outages/{outageName}/notifd</code></td>\n<td>to add a specific outage to the notifications.</td>\n</tr>\n</tbody>\n</table>\n\n### DELETEs (Removing Data)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>/sched-outages/{outageName}</code></td>\n<td>to delete a specific outage.</td>\n</tr>\n<tr>\n<td><code>/sched-outages/{outageName}/collectd/{package}</code></td>\n<td>to remove a specific outage from a collectd’s package.</td>\n</tr>\n<tr>\n<td><code>/sched-outages/{outageName}/pollerd/{package}</code></td>\n<td>to remove a specific outage from a pollerd’s package.</td>\n</tr>\n<tr>\n<td><code>/sched-outages/{outageName}/threshd/{package}</code></td>\n<td>to remove a specific outage from a threshd’s package.</td>\n</tr>\n<tr>\n<td><code>/sched-outages/{outageName}/notifd</code></td>\n<td>to remove a specific outage from the notifications.</td>\n</tr>\n</tbody>\n</table>\n6.9.27. SNMP Configuration\n\nYou can edit the community string, SNMP version, etc. for an IP address using this interface. If you make a change that would overlap with an existing snmp-config.xml, it will automatically create groups of `<definition />` entries as necessary. If no `<definition />` entry is created it matches the defaults.\n\nThere are different versions of the interface (see below). The following operations are supported:\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/snmpConfig/{ipAddress}</td>\n<td>Get the SNMP configuration for a given IP address.</td>\n</tr>\n<tr>\n<td>/snmpConfig/{ipAddress}?location={location}</td>\n<td>Get the SNMP configuration for a given IP address at a given location.</td>\n</tr>\n</tbody>\n</table>\n\nPUTs (Modifying Data)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/snmpConfig/{ipAddress}</td>\n<td>Add or update the SNMP configuration for a given IP address.</td>\n</tr>\n</tbody>\n</table>\n\nDetermine API version\n\nTo determine the version of the API running in your OpenNMS Horizon type `http://localhost:8980/opennms/rest/snmpConfig/1.1.1.1` in your browser and have a look at the output:\n\n- **Version 1**: If the output only have attributes community, port, retries, timeout and version\n- **Version 2**: If there are more attributes than described before (e.g. max Repetitions)\n\n**API Version 1**\n\nIn version 1 only a few attributes defined in `snmp-config.xsd` are supported. These are defined in `snmp-info.xsd`:\nThe following table shows all supported attributes, optional restrictions and the mapping between `snmp-info.xsd` and `snmp-config.xsd`. All parameters can be set regardless the version.\n\n<table>\n<thead>\n<tr>\n<th>attribute <code>snmp-info.xml</code></th>\n<th>attribute <code>snmp-config.xml</code></th>\n<th>default</th>\n<th>restricted to version</th>\n<th>restriction</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>version</td>\n<td>version</td>\n<td>v1</td>\n<td>-</td>\n<td>"v1", "v2c" or "v3" are valid arguments. If an invalid or empty argument is provided "v1" is used.</td>\n</tr>\n<tr>\n<td>port</td>\n<td>port</td>\n<td>161</td>\n<td>-</td>\n<td>Integer > 0</td>\n</tr>\n<tr>\n<td>retries</td>\n<td>retry</td>\n<td>1</td>\n<td>-</td>\n<td>Integer > 0</td>\n</tr>\n<tr>\n<td>timeout</td>\n<td>timeout</td>\n<td>3000</td>\n<td>-</td>\n<td>Integer > 0</td>\n</tr>\n<tr>\n<td>community</td>\n<td>read-community</td>\n<td>public</td>\n<td>-</td>\n<td>any string with a length >= 1</td>\n</tr>\n</tbody>\n</table>\nExample 1:\n\n```bash\ncurl -v -X PUT -H \"Content-Type: application/xml\" \\\n-H \"Accept: application/xml\" \\\n-d \"<snmp-info> \\\n <community>yRuSonoZ</community> \\\n <port>161</port> \\\n <retries>1</retries> \\\n <timeout>2000</timeout> \\\n <version>v2c</version> \\\n </snmp-info>\" \\\n-u admin:admin http://localhost:8980/opennms/rest/snmpConfig/10.1.1.1\n```\n\nCreates or updates a `<definition/>`-entry for IP address 10.1.1.1 in `snmp-config.xml`.\n\nExample 2:\n\n```bash\ncurl -v -X GET -u admin:admin http://localhost:8980/opennms/rest/snmpConfig/10.1.1.1\n```\n\nReturns the SNMP configuration for IP address 10.1.1.1 as defined in example 1.\n\nAPI Version 2\n\nSince Version 2 all attributes of a `<definition />` entry defined in `snmp-config.xsd` (http://xmlns.opennms.org/xsd/config/snmp) can be set or get via the interface - except it is only possible to set the configuration for one IP address and not for a range of IP addresses. This may change in the future.\n\nThe interface uses `SnmpInfo` objects for communication. Therefore it is possible to set for example v1 and v3 parameters in one request (e.g. `readCommunity` String and `privProtocol` String). However OpenNMS Horizon does not allow this. It is only allowed to set attributes which have no version restriction (e.g. timeout value) or the attributes which are limited to the version (e.g. `readCommunity` String if version is v1/v2c). The same is for getting data from the API, even if it is possible to store v1 and v3 parameters in one definition block in the `snmp-config.xml` manually, the ReST API will only return the parameters which match the version. If no version is defined, the default is assumed (both in `PUT` and `GET` requests).\n\nThe `SnmpInfo` schema is defined as follows:\nThe following table shows all supported attributes, the mapping between `snmp-info.xsd` and `snmp-config.xsd`. It also shows the version limitations, default values and the restrictions - if any.\n\n<table>\n<thead>\n<tr>\n<th>attribute <code>snmp-info.xsd</code></th>\n<th>attribute <code>snmp-config.xml</code></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>default</td>\n<td>restricted to version</td>\n</tr>\n<tr>\n<td>restriction</td>\n<td>version</td>\n</tr>\n<tr>\n<td>attribute</td>\n<td>snmp-config.xml attribute</td>\n</tr>\n<tr>\n<td>---------------------</td>\n<td>----------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>version</td>\n<td>v1</td>\n</tr>\n<tr>\n<td>-</td>\n<td>"v1", "v2c" or "v3" are valid arguments. If an invalid or empty argument is provided "v1" is used.</td>\n</tr>\n<tr>\n<td>port</td>\n<td>port</td>\n</tr>\n<tr>\n<td>161</td>\n<td>-</td>\n</tr>\n<tr>\n<td>Integer > 0</td>\n<td>retries</td>\n</tr>\n<tr>\n<td>retry</td>\n<td>1</td>\n</tr>\n<tr>\n<td>-</td>\n<td>Integer > 0</td>\n</tr>\n<tr>\n<td>timeout</td>\n<td>timeout</td>\n</tr>\n<tr>\n<td>3000</td>\n<td>-</td>\n</tr>\n<tr>\n<td>Integer > 0</td>\n<td>maxVarsPerPdu</td>\n</tr>\n<tr>\n<td>max-vars-per-pdu</td>\n<td>10</td>\n</tr>\n<tr>\n<td>-</td>\n<td>Integer > 0</td>\n</tr>\n<tr>\n<td>maxRepetitionSs</td>\n<td>max-repetitions</td>\n</tr>\n<tr>\n<td>2</td>\n<td>-</td>\n</tr>\n<tr>\n<td>Integer > 0</td>\n<td>maxRequestSize</td>\n</tr>\n<tr>\n<td>max-request-size</td>\n<td>65535</td>\n</tr>\n<tr>\n<td>-</td>\n<td>Integer > 0</td>\n</tr>\n<tr>\n<td>proxyHost</td>\n<td>proxy-host</td>\n</tr>\n<tr>\n<td>-</td>\n<td>readCommunity</td>\n</tr>\n<tr>\n<td>attribute snmp-info.xml</td>\n<td>attribute snmp-config.xml</td>\n</tr>\n<tr>\n<td>-------------------------</td>\n<td>--------------------------</td>\n</tr>\n<tr>\n<td>read-community</td>\n<td>public</td>\n</tr>\n<tr>\n<td>v1, v2c</td>\n<td></td>\n</tr>\n<tr>\n<td>writeCommunity</td>\n<td>write-community</td>\n</tr>\n<tr>\n<td>private</td>\n<td>v1, v2c</td>\n</tr>\n<tr>\n<td>securityName</td>\n<td></td>\n</tr>\n<tr>\n<td>security-name</td>\n<td>opennmsUser</td>\n</tr>\n<tr>\n<td>v3</td>\n<td></td>\n</tr>\n<tr>\n<td>securityLevel</td>\n<td>security-level</td>\n</tr>\n<tr>\n<td>noAuth NoPriv</td>\n<td>v3</td>\n</tr>\n</tbody>\n</table>\nattribute snmp-config.xml\n\n- Integer value, which can be null, 1, 2, or 3.\n - 1 means noAuth NoPriv\n - 2 means authNoPriv\n - 3 means authPriv\n\nIf you do not set the security level manually it is determined automatically:\n- if no authPassPhrase set the security Level is 1\n- if a authPassPhrase and no privPassPhrase set the security Level is 1\n<table>\n<thead>\n<tr>\n<th>attribute</th>\n<th>attribute snmp-config.xml</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>auth-passphrase</td>\n<td>0p3nNMSv3</td>\n</tr>\n<tr>\n<td>v3</td>\n<td></td>\n</tr>\n<tr>\n<td>authProtocol</td>\n<td>auth-protocol</td>\n</tr>\n<tr>\n<td>MD5</td>\n<td>v3</td>\n</tr>\n<tr>\n<td>only MD5 or SHA are valid arguments</td>\n<td>privPassPhrase</td>\n</tr>\n<tr>\n<td>privacy-passphrase</td>\n<td>0p3nNMSv3</td>\n</tr>\n<tr>\n<td>v3</td>\n<td></td>\n</tr>\n<tr>\n<td>privProtocol</td>\n<td>privacy-protocol</td>\n</tr>\n<tr>\n<td>DES</td>\n<td>v3</td>\n</tr>\n<tr>\n<td>only DES, AES, AES192 or AES256 are valid arguments.</td>\n<td>engineId</td>\n</tr>\n<tr>\n<td>engine-id</td>\n<td>v3</td>\n</tr>\n</tbody>\n</table>\n### Example 1:\n\n```\ncurl -v -X PUT -H \"Content-Type: application/xml\" \\\n -H \"Accept: application/xml\" \\\n -d \"<snmp-info> \n <readCommunity>yRuSonoZ</readCommunity> \n <port>161</port> \n <retries>1</retries> \n <timeout>2000</timeout> \n <version>v2c</version> \n </snmp-info>\" \\\n -u admin:admin http://localhost:8980/opennms/rest/snmpConfig/10.1.1.1\n```\n\nCreates or updates a `<definition/>`-entry for IP address 10.1.1.1 in `snmp-config.xml`.\n\n### Example 2:\n\n```\ncurl -v -X GET -u admin:admin http://localhost:8980/opennms/rest/snmpConfig/10.1.1.1\n```\n\nReturns the SNMP configuration for IP address 10.1.1.1 as defined in example 1.\nExample 3:\n\ncurl -v -X PUT -H \"Content-Type: application/xml\" \\\n-H \"Accept: application/xml\" \\\n-d \"<snmp-info> \\\n <readCommunity>yRuSonoZ</readCommunity> \\\n <port>161</port> \\\n <retries>1</retries> \\\n <timeout>2000</timeout> \\\n <version>v1</version> \\\n <securityName>secret-stuff</securityName> \\\n <engineId>engineId</engineId> \\\n </snmp-info>\" \\\n-u admin:admin http://localhost:8980/opennms/rest/snmpConfig/10.1.1.1\n\nCreates or updates a <definition/>-entry for IP address 10.1.1.1 in snmp-config.xml ignoring attributes securityName and engineId.\n\nExample 4:\n\ncurl -v -X PUT -H \"Content-Type: application/xml\" \\\n-H \"Accept: application/xml\" \\\n-d \"<snmp-info> \\\n <readCommunity>yRuSonoZ</readCommunity> \\\n <port>161</port> \\\n <retries>1</retries> \\\n <timeout>2000</timeout> \\\n <version>v3</version> \\\n <securityName>secret-stuff</securityName> \\\n <engineId>engineId</engineId> \\\n </snmp-info>\" \\\n-u admin:admin http://localhost:8980/opennms/rest/snmpConfig/10.1.1.1\n\nCreates or updates a <definition/>-entry for IP address 10.1.1.1 in snmp-config.xml ignoring attribute readCommunity.\n\n6.9.28. SNMP Interfaces\n\nObtain a list of SNMP interfaces based on a set of criteria.\n\nThis API is v2-only, and uses FIQL for querying.\n\nExamples:\n\n- /api/v2/snmpinterfaces?_s=node.label==onms-prd-01\n- /api/v2/snmpinterfaces?_s=ifIndex==6\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/snmpinterfaces</td>\n<td>Get all SNMP interfaces for the given search criteria.</td>\n</tr>\n</tbody>\n</table>\n\nExample:\n\nGet SNMP interfaces whose node are in the foreign source *Servers* and are associated with IP address *127.0.0.1*:\n\n```\ncurl -u admin:admin http://localhost:8980/opennms/api/v2/snmpinterfaces?\n _s=node.foreignSource==Servers;ipInterfaces.ipAddress=127.0.0.1\n```\n\nPUTs/POSTs (Modifying Data)\n\nThe `/snmpinterfaces` ReST API is read-only. If you wish to create new SNMP interfaces, use the `snmpinterfaces` resources under the `nodes` endpoint.\n\n6.9.29. Users\n\nSince users are not currently stored in the database, the ReST interface for them is not as full-fledged as that of nodes, etc.\n\n⚠️ You cannot use hibernate criteria for filtering. You may need to touch the `$OPENNMS_HOME/etc/users.xml` file on the filesystem for any addition or modification actions to take effect (see NMS-6469 for details).\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/users</td>\n<td>Get a list of users.</td>\n</tr>\n<tr>\n<td>/users/</td>\n<td>Get a specific user, by username.</td>\n</tr>\n<tr>\n<td>{username}</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nPOSTs (Adding Data)\n### PUTs (Modifying Data)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/users</td>\n<td>Add a user. If supplying a password it is assumed to be hashed or encrypted already, at least as of 1.12.5. To indicate that the supplied password uses the salted encryption algorithm rather than the older MD5 based algorithm, you need to pass an element named <code>passwordSalt</code> with text <code>true</code> after the password element (or key/value pairs if using JSON). Note: You may add the query parameter <code>hashPassword=true</code> to tell OpenNMS you are passing an unencrypted password; it will hash and salt the password when it is saved.</td>\n</tr>\n<tr>\n<td>/users/{username}</td>\n<td>Update an existing user's full-name, user-comments, password, passwordSalt and duty-schedule values. Note: If you are setting the password, you may also add the query parameter <code>hashPassword=true</code> to tell OpenNMS you are passing an unencrypted password; it will hash and salt the password when it is saved.</td>\n</tr>\n<tr>\n<td>/users/{username}/roles/{rolename}</td>\n<td>Add a security role to the user. (new in OpenNMS 19)</td>\n</tr>\n</tbody>\n</table>\n\n### DELETEs (Removing Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/users/{username}</td>\n<td>Delete a user.</td>\n</tr>\n<tr>\n<td>/users/{username}/roles/{rolename}</td>\n<td>Remove a security role from the user. (new in OpenNMS 19)</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.30. User Defined Links\n\nUser defined links (UDLs) for the Enlinkd topology can be queried, added, modified or deleted via ReST endpoints.\n\n#### GETs (Reading UDLs)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>api/v2/userdefinedlinks</td>\n<td>Get the list of UDLs.</td>\n</tr>\n<tr>\n<td>api/v2/userdefinedlinks/{id}</td>\n<td>Retrieve a specific UDL by database ID.</td>\n</tr>\n</tbody>\n</table>\n\n#### POSTs (Creating UDLs)\nUsage examples with curl\n\nCreate a new UDL between node with ID 1 and node with ID 2.\n\n```\ncurl -v -X POST -u admin:admin -H \"Content-Type: application/json\" -d '{\"node-id-a\": 1, \"node-id-z\": 2, \"component-label-a\": \"tp1\", \"component-label-z\": \"tp2\", \"link-id\": \"n1:tp1->n2:tp2\", \"owner\": \"me\"}'\nhttp://localhost:8980/opennms/api/v2/userdefinedlinks\n```\n\nDELETEs (Removing UDLs)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>api/v2/userdefinedlinks/{id}</td>\n<td>Delete a UDL by database ID.</td>\n</tr>\n</tbody>\n</table>\n\n6.9.31. SNMP Trap Northbounder Interface Configuration\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/snmptrap-nbi</td>\n<td>Gets full content of the configuration.</td>\n</tr>\n<tr>\n<td>/config/snmptrap-nbi/status</td>\n<td>Gets the status of the SNMP Trap NBI (returns either true or false).</td>\n</tr>\n<tr>\n<td>/config/snmptrap-nbi/destinations</td>\n<td>Gets the name of all the existing destinations.</td>\n</tr>\n<tr>\n<td>/config/snmptrap-nbi/destinations/{name}</td>\n<td>Gets the content of the destination named {name}</td>\n</tr>\n</tbody>\n</table>\n\nPUTs (Update defaults)\n\nOn a successful request, the Syslog NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/snmptrap-nbi/status?enabled=(true;false)</td>\n<td>Sets the status of the SNMP Trap NBI.</td>\n</tr>\n</tbody>\n</table>\n\nPOSTs (Adding Data)\n\nPOST requires form data using application/x-www-form-urlencoded as a Content-Type.\n\nOn a successful request, the SNMP Trap NBI will be notified about the configuration change.\n### PUTs (Modifying Data)\n\nPUT requires form data using application/x-www-form-urlencoded as a Content-Type.\n\nOn a successful request, the SNMP Trap NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/snmptrap-nbi</td>\n<td>Updates the full content of the configuration.</td>\n</tr>\n<tr>\n<td>/config/snmptrap-nbi/destinations</td>\n<td>Adds a new or overrides an existing destination.</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/snmptrap-nbi/destinations/{name}</td>\n<td>Updates the content of the destination named {name}</td>\n</tr>\n</tbody>\n</table>\n\n### DELETEs (Remove Data)\n\nOn a successful request, the SNMP Trap NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/snmptrap-nbi/destinations/{name}</td>\n<td>Updates the content of the destination named {name}</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.32. Email Northbounder Interface Configuration\n\n#### GETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/email-nbi</td>\n<td>Gets full content of the configuration.</td>\n</tr>\n<tr>\n<td>/config/email-nbi/status</td>\n<td>Gets the status of the Email NBI (returns either true or false).</td>\n</tr>\n<tr>\n<td>/config/email-nbi/destinations</td>\n<td>Gets the name of all the existing destinations.</td>\n</tr>\n<tr>\n<td>/config/email-nbi/destinations/{name}</td>\n<td>Gets the content of the destination named {name}</td>\n</tr>\n</tbody>\n</table>\n\n#### PUTs (Update defaults)\n\nOn a successful request, the Email NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/email-nbi/status?enabled=(true;false)</td>\n<td>Sets the status of the Email NBI.</td>\n</tr>\n</tbody>\n</table>\n**POSTs (Adding Data)**\n\nPOST requires form data using application/x-www-form-urlencoded as a Content-Type.\n\nOn a successful request, the Email NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/email-nbi/destinations</td>\n<td>Adds a new or overrides an existing destination.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Data)**\n\nPUT requires form data using application/x-www-form-urlencoded as a Content-Type.\n\nOn a successful request, the Email NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/email-nbi/destinations/{name}</td>\n<td>Updates the content of the destination named {name}</td>\n</tr>\n</tbody>\n</table>\n\n**DELETEs (Remove Data)**\n\nOn a successful request, the Email NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/email-nbi/destinations/{name}</td>\n<td>Updates the content of the destination named {name}</td>\n</tr>\n</tbody>\n</table>\n\n**6.9.33. Javamail Configuration**\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/javamail/default/readmail</td>\n<td>Get the name of the default readmail config.</td>\n</tr>\n<tr>\n<td>/config/javamail/default/sendmail</td>\n<td>Get the name of the default sendmail config.</td>\n</tr>\n<tr>\n<td>/config/javamail/readmails</td>\n<td>Get the name of all the existing readmail configurations.</td>\n</tr>\n<tr>\n<td>/config/javamail/sendmails</td>\n<td>Get the name of all the existing sendmail configurations.</td>\n</tr>\n<tr>\n<td>/config/javamail/end2ends</td>\n<td>Get the name of all the existing end2end mail configurations.</td>\n</tr>\n<tr>\n<td>/config/javamail/readmails/{name}</td>\n<td>Get the content of the readmail configuration named {name}</td>\n</tr>\n<tr>\n<td>/config/javamail/sendmails/{name}</td>\n<td>Get the content of the sendmail configuration named {name}</td>\n</tr>\n<tr>\n<td>Resource</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------------------------------</td>\n<td>-----------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>/config/javamail/end2ends/{name}</td>\n<td>Get the content of the end2end mail configuration named {name}</td>\n</tr>\n</tbody>\n</table>\n\n**POSTs (Adding/Updating Data)**\n\nPOST requires form data using application/xml or application/json as a Content-Type.\n\nOn a successful request, the Email NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/javamail/readmails</td>\n<td>Adds a new or overrides an existing readmail configuration.</td>\n</tr>\n<tr>\n<td>/config/javamail/sendmails</td>\n<td>Adds a new or overrides an existing sendmail configuration.</td>\n</tr>\n<tr>\n<td>/config/javamail/end2ends</td>\n<td>Adds a new or overrides an existing end2ends mail configuration.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Update defaults)**\n\nOn a successful request, the Email NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>config/javamail/default/readmail/{name}</td>\n<td>Sets the readmail named {name} as the new default.</td>\n</tr>\n<tr>\n<td>config/javamail/default/sendmail/{name}</td>\n<td>Sets the sendmail named {name} as the new default.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Data)**\n\nPUT requires form data using application/x-www-form-urlencoded as a Content-Type.\n\nOn a successful request, the Email NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/javamail/readmails/{name}</td>\n<td>Updates the content of the readmail configuration named {name}</td>\n</tr>\n<tr>\n<td>/config/javamail/sendmails/{name}</td>\n<td>Updates the content of the sendmail configuration named {name}</td>\n</tr>\n<tr>\n<td>/config/javamail/end2ends/{name}</td>\n<td>Updates the content of the end2end mail configuration named {name}</td>\n</tr>\n</tbody>\n</table>\n\n**DELETEs (Remove Data)**\n\nOn a successful request, the Email NBI will be notified about the configuration change.\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/javamail/readmails/{name}</td>\n<td>Removes the readmail configuration named {name}</td>\n</tr>\n<tr>\n<td>/config/javamail/sendmails/{name}</td>\n<td>Removes the sendmail configuration named {name}</td>\n</tr>\n<tr>\n<td>/config/javamail/end2ends/{name}</td>\n<td>Removes the end2end mail configuration named {name}</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.34. Syslog Northbounder Interface Configuration\n\n**GETs (Reading Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/syslog-nbi</td>\n<td>Gets full content of the configuration.</td>\n</tr>\n<tr>\n<td>/config/syslog-nbi/status</td>\n<td>Gets the status of the Syslog NBI (returns either true or false).</td>\n</tr>\n<tr>\n<td>/config/syslog-nbi/destinations</td>\n<td>Gets the name of all the existing destinations.</td>\n</tr>\n<tr>\n<td>/config/syslog-nbi/destinations/{name}</td>\n<td>Gets the content of the destination named {name}</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Update defaults)**\n\nOn a successful request, the Syslog NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/syslog-nbi/status?enabled=(true;false)</td>\n<td>Sets the status of the Syslog NBI.</td>\n</tr>\n</tbody>\n</table>\n\n**POSTs (Adding Data)**\n\nPOST requires form data using application/x-www-form-urlencoded as a Content-Type.\n\nOn a successful request, the Syslog NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/syslog-nbi</td>\n<td>Updates the full content of the configuration.</td>\n</tr>\n<tr>\n<td>/config/syslog-nbi/destinations</td>\n<td>Adds a new or overrides an existing destination.</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Data)**\n\nPUT requires form data using application/x-www-form-urlencoded as a Content-Type.\n\nOn a successful request, the Syslog NBI will be notified about the configuration change.\n### Resource Description\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/syslog-nbi/destinations/{name}</td>\n<td>Updates the content of the destination named {name}</td>\n</tr>\n</tbody>\n</table>\n\n**DELETEs (Remove Data)**\n\nOn a successful request, the Syslog NBI will be notified about the configuration change.\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/config/syslog-nbi/destinations/{name}</td>\n<td>Updates the content of the destination named {name}</td>\n</tr>\n</tbody>\n</table>\n\n### 6.9.35. Business Service Monitoring\n\nEvery aspect of the *Business Service Monitoring* feature can be controlled via a ReST API. The API's endpoint for managing *Business Services* is located at `/opennms/api/v2/business-services`. It supports XML content to represent the *Business Services*. The schema file describing the API model is located in `$OPENNMS_HOME/share/xsds/business-service-dto.xsd`. The responses generated by the ReST API do also include `location` elements that contain references to other entities managed by the API. The *Business Service* response data model for the ReST API has the following basic structure:\n\n**Sample Business Service details response XML representation**\n\n```xml\n<business-service>\n <id>42</id>\n <name>Datacenter North</name>\n <attributes/>\n <ip-service-edges>\n <ip-service-edge>\n <id>23</id>\n <operational-status>WARNING</operational-status>\n <map-function>\n <type>Identity</type>\n </map-function>\n <location>/api/v2/business-services/2/edges/23</location>\n </ip-service-edge>\n </ip-service-edges>\n <reduction-key-edges>\n <reduction-key-edge>\n <id>111</id>\n <operational-status>INDETERMINATE</operational-status>\n <map-function>\n <type>Identity</type>\n </map-function>\n <location>/api/v2/business-services/2/edges/23</location>\n </reduction-key-edge>\n </reduction-key-edges>\n</business-service>\n```\n\n*Location elements* contain references to other entities managed by the API.\n<map-function>\n <location>/api/v2/business-services/42/edges/111</location>\n <reduction-keys>\n <reduction-key>my-reduction-key1</reduction-key>\n </reduction-keys>\n <weight>1</weight>\n</map-function>\n\n<child-edges>\n <child-edge>\n <id>123</id>\n <operational-status>MINOR</operational-status>\n <map-function>\n <type>Identity</type>\n </map-function>\n <location>/api/v2/business-services/42/edges/123</location>\n <reduction-keys/>\n <weight>1</weight>\n <child-id>43</child-id>\n </child-edge>\n</child-edges>\n\n<parent-services><parent-service>144</parent-service></parent-services>\n<reduce-function><type>HighestSeverity</type></reduce-function>\n<operational-status>INDETERMINATE</operational-status>\n<location>/api/v2/business-services/146</location>\n</business-service>\nSample Business Service creation request XML representation\n\n```xml\n<business-service>\n <name>Datacenter North</name>\n <attributes/>\n <ip-service-edges>\n <ip-service-edge>\n <ip-service-id>99</ip-service-id>\n <map-function>\n <type>Identity</type>\n </map-function>\n <weight>1</weight>\n </ip-service-edge>\n </ip-service-edges>\n <reduction-key-edges>\n <reduction-key-edge>\n <reduction-key>my-reduction-key1</reduction-key>\n <map-function>\n <type>Identity</type>\n </map-function>\n <weight>1</weight>\n </reduction-key-edge>\n </reduction-key-edges>\n <child-edges>\n <child-edge>\n <child-id>43</child-id>\n <map-function>\n <type>Identity</type>\n </map-function>\n <weight>1</weight>\n </child-edge>\n </child-edges>\n <reduce-function><type>HighestSeverity</type></reduce-function>\n</business-service>\n```\n\nThe whole model is defined in jetty-webapps/opennms/WEB-INF/lib/org.opennms.features.bsm.rest.api-*.jar which can be used as a dependency for a Java program to query the API.\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code>/opennms/api/v2/business-services</code></td>\n<td>Provides a brief list of all defined Business Services</td>\n</tr>\n<tr>\n<td><code>/opennms/api/v2/business-services/{id}</code></td>\n<td>Returns the Business Service identified by <code>id</code> included the current operational state</td>\n</tr>\n<tr>\n<td><code>/opennms/api/v2/business-services/edges/{edgeId}</code></td>\n<td>Returns the edge of the Business Service identified by <code>edgeId</code></td>\n</tr>\n<tr>\n<td>Resource</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>----------</td>\n<td>-------------</td>\n</tr>\n<tr>\n<td>/opennms/api/v2/business-services/functions/map</td>\n<td>Provides a list of supported Map Function definitions</td>\n</tr>\n<tr>\n<td>/opennms/api/v2/business-services/functions/map/{name}</td>\n<td>Returns the definition of the Map Function identified by name</td>\n</tr>\n<tr>\n<td>/opennms/api/v2/business-services/functions/reduce/</td>\n<td>Provides a list of supported Reduce Function definitions</td>\n</tr>\n<tr>\n<td>/opennms/api/v2/business-services/functions/reduce/{name}</td>\n<td>Returns the definition of the Reduce Function identified by name</td>\n</tr>\n</tbody>\n</table>\n\n**PUTs (Modifying Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/opennms/api/v2/business-services/{id}</td>\n<td>Modifies an existing Business Service identified by id</td>\n</tr>\n</tbody>\n</table>\n\n**POSTs (Adding Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/opennms/api/v2/business-services</td>\n<td>Creates a new Business Service</td>\n</tr>\n<tr>\n<td>/opennms/api/v2/business-services/{id}/ip-service-edge</td>\n<td>Adds an edge of type IP Service to the Business Service identified by id</td>\n</tr>\n<tr>\n<td>/opennms/api/v2/business-services/{id}/reduction-key-edge</td>\n<td>Adds an edge of type Reduction Key to the Business Service identified by id</td>\n</tr>\n<tr>\n<td>/opennms/api/v2/business-services/{id}/child-edge</td>\n<td>Adds an edge of type Business Service to the Business Service identified by id</td>\n</tr>\n<tr>\n<td>/opennms/api/v2/daemon/reload</td>\n<td>Reload the configuration of the Business Service Daemon</td>\n</tr>\n</tbody>\n</table>\n\n**DELETEs (Removing Data)**\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/opennms/api/v2/business-services/{id}</td>\n<td>Deletes the Business Service identified by id</td>\n</tr>\n<tr>\n<td>/opennms/api/v2/business-services/{id}/edges/{edgeId}</td>\n<td>Removes an edge with the identifier edgeId from the Business Service identified by id</td>\n</tr>\n</tbody>\n</table>\n\n**6.9.36. Discovery**\n\nThis endpoint can be used to trigger a one-time discovery scan.\nPOSTs (Submitting one-time scan configuration)\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/opennms/api/v2/discovery</td>\n<td>Submits an one-time scan configuration</td>\n</tr>\n</tbody>\n</table>\n\nThe following XML structure is used to define a scan job.\n\nSample configuration file discovery.xml\n\n```xml\n<discoveryConfiguration>\n <specifics>\n <specific>\n <location>Default</location>\n <retries>3</retries>\n <timeout>2000</timeout>\n <foreignSource>My-ForeignSource</foreignSource>\n <content>192.0.2.1</content>\n </specific>\n </specifics>\n <includeRanges>\n <includeRange>\n <location>Default</location>\n <retries>3</retries>\n <timeout>2000</timeout>\n <foreignSource>My-ForeignSource</foreignSource>\n <begin>192.0.2.10</begin>\n <end>192.0.2.254</end>\n </includeRange>\n </includeRanges>\n <excludeRanges>\n <excludeRange>\n <begin>192.0.2.60</begin>\n <end>192.0.2.65</end>\n </excludeRange>\n </excludeRanges>\n <includeUrls>\n <includeUrl>\n <location>Default</location>\n <retries>3</retries>\n <timeout>2000</timeout>\n <foreignSource>My-ForeignSource</foreignSource>\n <content>http://192.0.2.254/addresses.txt</content>\n </includeUrl>\n </includeUrls>\n</discoveryConfiguration>\n```\n\nThe scan itself can be triggered by posting the configuration to the ReST endpoint as follows:\nTrigger one-time scan\n\n```\ncurl -H \"Content-Type: application/xml\" -u admin:admin -X POST -d @discovery.xml\nhttp://localhost:8980/opennms/api/v2/discovery\n```\n\n6.9.37. Situation Feedback\n\nSituation Feedback is an optional feature that allows for the management of User Contributed Feedback regarding Correlation of Alarms.\n\nIt is a simple API that allows for the submission and retrieval of Correlation Feedback.\n\nGETs (Reading Data)\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/situation-feedback/{situationId}</td>\n<td>Get Situation Feedback for the Situation with AlarmId = {situationId}.</td>\n</tr>\n</tbody>\n</table>\n\n- situationId is the same as the AlarmId for the Situation.\n\nUsage examples with curl\n\nRetrieval Situation Feedback for the Situation with AlarmId == 210\n\n```\ncurl -u admin:admin \"http://localhost:8980/opennms/rest/situation-feedback/210\"\n```\nPOSTs (Adding Data)\n\nPOST requires using application/json as a Content-Type.\n\nOn a successful request, the Feedback will be persisted\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>/situation-feedback/{situationId}</td>\n<td>Submits feedback for the Situation identified with AlarmId = {situationId}.</td>\n</tr>\n</tbody>\n</table>\n\nUsage examples with curl\n\nSubmit positive Feedback for a Situation with 2 alarms.\n\n```\ncurl -X POST -H \"Accept: application/json\" -H \"Content-Type: application/json\" -u admin:admin -d @feedback.json http://127.0.0.1:8980/opennms/rest/situation-feedback/210\n```\nResponse\n204 No Content\n\n6.10. ReST API Examples\n\n6.10.1. Getting Graph data\n\nWhile graphs aren't technically available via ReST, you can parse some ReST variables to get enough data to pull a graph. This isn't ideal because it requires multiple fetches, but depending on your use case, this may be adequate for you.\n\nI'm in-lining some sample PHP code which should do this (not tested at all, cut & paste from old code I have that does not use the ReST- interface, and/or coded straight into the browser so YMMV). If you go to your NMS and click the resource graphs, then right click the graph you want and hit View Image you will get the full URL that would need to be passed to pull that graph as a standalone image.\n\nFrom that just take the URL and plug in the values you pulled from ReST to get a graph for whatever node you wanted.\nfunction fetchit($thing, $user = \"user\", $pass = \"pass\") {\n $url = \"http://localhost:8980/opennms\";\n $ch = curl_init();\n curl_setopt($ch, CURLOPT_URL, $url . $thing);\n curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);\n curl_setopt($ch, CURLOPT_USERAGENT, $useragent);\n $url = \"http://localhost:8980/opennms\";\n $ch = curl_init();\n curl_setopt($ch, CURLOPT_URL, $url . $thing);\n curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);\n curl_setopt($ch, CURLOPT_USERAGENT, $useragent);\n $data = curl_exec($ch);\n curl_close($ch);\n return $data;\n}\n\n// this assumes you already have found the nodeId via a previous REST call or some\n// other means. Provided more as an example than what you might want.\nfunction getNodeInterfaces($nodeId) {\n $data = fetchit(\"/rest/nodes/$nodeId/snmpinterfaces\");\n return simplexml_load_string($data);\n}\n\nfunction fetchGraphs($nodeId) {\n $ints = getNodeInterfaces($nodeId);\n $chars = array('/', '.', ':', ' ', '-', ' ');\n $endtime = time();\n $starttime = (string)(time() - ($days * 24 * 60 * 60));\n\n // use bcmath or a better version of PHP if you don't want this hypocrisy here.\n $endtime = $endtime . '000';\n $starttime = $starttime . '000';\n\n for($i=0; $i<count($ints->snmpInterfaces); $i++) {\n $ifname = $ints->snmpInterfaces[$i]->snmpInterface->ifName;\n $mac = $ints->snmpInterfaces[$i]->snmpInterface->physAddr;\n $if = str_replace($chars, \"\", $ifname);\n if ( strlen(trim($mac)) < 12 ) {\n $mac_and_if = $if; } else { $mac_and_if = $if . '.'. $mac; };\n\n $image = fetchit(\"$url/graph/graph.png?resource=node[$nodeId].interfaceSnmp[$mac_and_if]&report=report=mib2.HCbits&start=$starttime&end=$endtime\")\n ;\n\n // you can poop this to a file now, or set header('Content-type: image/png');\n then print \"$image\";\n }\n}\n\n6.10.2. provision.pl examples and notes\n\nOne way to test out the new ReST interface is to use provision.pl. If you run it you'll get a summary\nof the output, but it's not totally obvious how it all works.\nHere is an example of adding a new node using the ReST interface:\n\n```plaintext\n# add a new foreign source called ubr\n/usr/share/opennms/bin/provision.pl requisition add ubr\n/usr/share/opennms/bin/provision.pl node add ubr 10341111 clownbox\n/usr/share/opennms/bin/provision.pl node set ubr 10341111 city clownville\n/usr/share/opennms/bin/provision.pl node set ubr 10341111 building clown-town-hall\n/usr/share/opennms/bin/provision.pl node set ubr 10341111 parent-foreign-id 1122114\n/usr/share/opennms/bin/provision.pl interface add ubr 10341111 10.1.3.4\n\n# this is like a commit. No changes will take effect until you import a foreign source\n/usr/share/opennms/bin/provision.pl requisition import ubr\n```\n\nYou will probably need to specify the username/password of an admin. To do this add:\n\n```plaintext\n--username=admin --password=clownnms\n```\n\nto the command line.\n\n### 6.10.3. Debian (Lenny) Notes\n\nFor Lenny, you'll need to pull a package out of backports to make everything work right. Read [http://backports.org/dokuwiki/doku.php?id=instructions](http://backports.org/dokuwiki/doku.php?id=instructions) for instructions on adding it to `sources.list`.\n\n```plaintext\n# install liburi-perl from backports\nsudo apt-get -t lenny-backports install liburi-perl\n```\n\n### 6.10.4. Windows Powershell ReST\n\nExample of using Windows Powershell to fill some asset fields with ReST.\n# Install date of Windows\n$wmi = Get-WmiObject -Class Win32_OperatingSystem\n$dateInstalled = $wmi.ConvertToDateTime($wmi.InstallDate)\n\n# Serial number and manufacturer of server\nGet-WmiObject win32_bios | select SerialNumber\n$wmi = Get-WmiObject -Class win32_bios\n$manufacturer = $wmi.Manufacturer\n\n# Text file with a description of the server for the comments field\n$comment = Get-Content \"C:\\Program Files\\BGInfo\\Info_Description.txt\" | Out-String\n$user = \"admin\"\n$pass = \"admin\"\n\n$secpasswd = ConvertTo-SecureString $user -AsPlainText -Force\n$cred = New-Object System.Management.Automation.PSCredential ($pass, $secpasswd)\n\n$nodeid = Invoke-RestMethod -Uri http://opennms.domain.nl:8980/opennms/rest/nodes?label=servername.domain.nl -Credential $cred\n$nodeid = $nodeid.nodes.node.id\n\n$uri = \"http://opennms.domain.nl:8980/opennms/rest/nodes/$nodeid/assetRecord\"\nInvoke-RestMethod -Uri $uri -Credential $cred -Method PUT\nInvoke-RestMethod -Uri \"$uri/?manufacturer=$manufacturer\" -Credential $cred -Method PUT\nInvoke-RestMethod -Uri \"$uri/?dateInstalled=$dateInstalled\" -Credential $cred -Method PUT\nInvoke-RestMethod -Uri \"$uri/?comment=$comment\" -Credential $cred -Method PUT\nChapter 7. Develop Documentation\n\nThis document is the guideline for people who wish to contribute to writing documentation for the OpenNMS project. The OpenNMS software is free and open source, contribution of any kind is welcome. We ask that you observe the rules and guidelines outlined here to maintain consistency across the project.\n\nEach (sub)project is represented as a section of the documentation. Each section will produce a HTML output in the file system that is generated in the `target/generated` sources folder.\n\nThe chosen file format for documentation is AsciiDoc (Asciidoc Homepage). Document files use the `.adoc` file extension.\n\nNote that there are different ways to contribute documentation, each suitable for the different use cases:\n\n- Tutorials and How To’s should be published on the OpenNMS Wiki. For example: you want to describe how to use the Net-SNMP agent and the SNMP monitor from OpenNMS to solve a special use case with OpenNMS.\n\n- The documentation in the source code should be formal technical documentation. The writing style should be accurate and concise. However, ensure that you explain concepts in detail and do not make omissions.\n\n### 7.1. File Structure in opennms-doc\n\n<table>\n<thead>\n<tr>\n<th>Directory</th>\n<th>Contents</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>guide-admin/</td>\n<td>module with the guide for administrators configuring, optimizing and running OpenNMS</td>\n</tr>\n<tr>\n<td>guide-development/</td>\n<td>module with the guide for those who want to develop OpenNMS</td>\n</tr>\n<tr>\n<td>guide-install/</td>\n<td>module with the guide of how to install OpenNMS on different operating systems</td>\n</tr>\n<tr>\n<td>releasenotes/</td>\n<td>module with the changelog and release notes</td>\n</tr>\n</tbody>\n</table>\n\n### 7.2. Writing\n\nThe following rules will help you to commit correctly formatted and prepared documentation for inclusion in the OpenNMS project. It is important that we maintain a level of consistency across all of our committers and the documentation they produce.\n\nWhen writing place a single sentence on each line. This makes it easy to move content around, and also easy to spot long, or fragmented, sentences. This will also allow us to assign comments on a sentence in GitHub which will facilitate easier merging.\nOther than writing documentation, you can help out by providing comments on documentation, reviewing, suggesting improvements or reporting bugs. To do this head over to GitHub.\n\n### 7.2.1. Conventions for text formatting\n\nThe following conventions are used:\n\n- File names and path are written in `poller-configuration.xml` they will be rendered in: `poller-configuration.xml`;\n- Names that indicate special attention, e.g., this configuration matches *any* entry: this is rendered as: this configuration matches `any` entry;\n- `_Italics_` is rendered as Italics and used for emphasis and indicates internal names and abbreviations;\n- `*Bold*` is rendered as Bold and should be used sparingly, for strong emphasis only;\n- `+methodName()+` is rendered as methodName() and is also used for literals, (note: the content between the + signs will be parsed);\n- `command` is rendered as command (typically used for command-line or parts used in configuration files) (note: the content between the ` signs will not be parsed);\n- `\\my/path/` is rendered as `my/path/`. This is used for file names and paths;\n- `\\``double quote'' (which is two grave accents to the left and two acute accents to the right) renders as `double quote'';\n- `\\`single quote' (which is a single grave accent to the left and a single acute accent to the right) renders as `single quote'.\n\n### 7.2.2. Gotchas\n\n- Always leave a blank line at the top of the documents section. It might be the title ends up in the last paragraph of the document.\n- Start in line 2 setting a relative path to the images directory to picture rendering on GitHub:\n\n```\n// Allow image rendering\n:imagesdir: relative/path/to/images/dir\n```\n\n- Always leave a blank line at the end of documents.\n- As `{}` are used for Asciidoc attributes, everything inside will be treated as an attribute. To avoid this you have to escape the opening brace: `{`. If you do not escape the opening brace, the braces and the text inside them will be removed without any warning.\n- Force line breaks with `\\`+` at the end of the line followed by a line break.\n7.3. Headings and document structure\n\nEach document starts with headings from level zero (the document title). Each document should have an ID. In some cases sections in the document also need to have ID’s; this depends on where they fit in the overall structure. If you wish to have a link to specific content that content has to have an ID. A missing ID in a mandatory place will cause the build to fail.\n\nTo start a document:\n\n```\n[[unique-id-verbose-is-ok]]\n= The Document Title\n```\n\nIf you are including the document inside another document and you need to push the headings down to the right level in the output, use the leveloffset attribute.\n\nSubsequent headings in a document should use the following syntax:\n\n```\n== Subheading\n\n... content here ...\n\n=== Subsubheading\n\ncontent here ...\n```\n\n7.4. Links\n\nUse the target ID to link to other parts of the manual. To use a target ID, use this syntax:\n\n```\n<<doc-guidelines-links>>\n```\n\nThis will render as: Links\n\nTo use the target ID in you document simply write the target ID in your text, for example:\nsee <<target-id>>\n\nthis should suffice for most cases.\n\nIf you need to link to another document with your own link text, use this syntax:\n\n```\n<<target-id, link text that fits in the context>>\n```\n\nHaving a lot of linked text may work well in a web context but is distracting in print. The documentation is intended for both media so be considerate of this in your usage.\n\nTo use an external link, use this syntax:\n\n```\nhttp://www.opennms.org/[Link text here]\n```\n\nThis will render in the output as: Link text here\n\nFor short links it may be beneficial not to use accompanying link text:\n\n```\nhttp://www.opennms.org/\n```\n\nWhich renders as: http://www.opennms.org/\n\nIt is acceptable to have a period trailing after the URL, it will not render as a part of the link.\n\n### 7.5. Admonitions and useful notes\n\nUse to define specific sections, such as Notes, Tips and Important information. We encourage their use in the documentation as long as they are used appropriately. Choose from the following:\n\n**Source template for making a note for additional hints**\n\n```\nNOTE: This is my note.\n```\n\nThis is how its rendered:\n\nThis is my note.\n\n**Source for giving a tip**\n\n```\nTIP: This is my tip.\n```\n\nThis is my tip.\nThis is how it's rendered:\n\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><img src=\"lightbulb.png\" alt=\"💡\" /></td>\n<td>This is my tip.</td>\n</tr>\n</tbody>\n</table>\n\n**Source for giving a important hint**\n\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><img src=\"lightbulb.png\" alt=\"💡\" /></td>\n<td>IMPORTANT: This is my important hint.</td>\n</tr>\n</tbody>\n</table>\n\nThis is how it's rendered:\n\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><img src=\"warning.png\" alt=\"⚠️\" /></td>\n<td>This is my important hint.</td>\n</tr>\n</tbody>\n</table>\n\n**Source for giving a caution**\n\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><img src=\"warning.png\" alt=\"⚠️\" /></td>\n<td>CAUTION: This is my caution.</td>\n</tr>\n</tbody>\n</table>\n\nThis is how it's rendered:\n\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><img src=\"fire.png\" alt=\"🔥\" /></td>\n<td>This is my caution.</td>\n</tr>\n</tbody>\n</table>\n\n**Source for giving a warning**\n\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><img src=\"warning.png\" alt=\"⚠️\" /></td>\n<td>WARNING: This is my warning.</td>\n</tr>\n</tbody>\n</table>\n\nThis is how it's rendered:\n\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><img src=\"warning.png\" alt=\"⚠️\" /></td>\n<td>This is my warning.</td>\n</tr>\n</tbody>\n</table>\n\nA multiline variation:\n\n<table>\n<thead>\n<tr>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>TIP: Tiptext. +</td>\n</tr>\n<tr>\n<td>Line 2.</td>\n</tr>\n</tbody>\n</table>\n\nWhich is rendered as:\n\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><img src=\"lightbulb.png\" alt=\"💡\" /></td>\n<td>Tiptext.</td>\n</tr>\n<tr>\n<td><img src=\"lightbulb.png\" alt=\"💡\" /></td>\n<td>Line 2.</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Text</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><img src=\"info.png\" alt=\"ℹ️\" /></td>\n<td>Remember to write these in full caps. There is no easy way to add new admonition types; do not create your own.</td>\n</tr>\n</tbody>\n</table>\n\n### 7.6. Attributes\n\nCommon attributes you can use in documents:\nThese can substitute part of URLs that point to, for example, APIdocs or source code. Note that opennms-git-tag also handles the case of snapshot/master.\n\nSample Asciidoc attributes you can use:\n\n- `{docdir}` - root directory of the documents\n- `{nbsp}` - non-breaking space\n\n### 7.7. Comments\n\nThere’s a separate build that includes comments. When the comments are used they show up with a yellow background. This build doesn’t run by default, but after a normal build, you can use `make annotated` to create a build yourself. You can use the resulting 'annotated' page to search for content as the full manual is a single page.\n\nTo write a comment:\n\n```\n// this is a comment\n```\n\nComments are not visible in the standard build. Comment blocks won’t be included in the output of any build. The syntax for a comment block is:\n\n```\n////\nNote included in here will still be processed, but not make it into the output.\nThat is, missing includes here will still break the build!\n////\n```\n\n### 7.8. Tables\n\nUse tables to represent structured information. A table is constructed in the following manner:\n\n```\n[options=\"header, autowidth\"]\n|---\n| Parameter | Description | Required | Default value\n| `myFirstParm` | my first long description | required | `myDefault`\n| `myScndParm` | my second long description | required | `myDefault`\n|---\n```\n\nThis is rendered as:\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n<th>Required</th>\n<th>Default value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>myFirstParm</td>\n<td>my first long description</td>\n<td>required</td>\n<td>myDefault</td>\n</tr>\n<tr>\n<td>myScndParm</td>\n<td>my second long description</td>\n<td>required</td>\n<td>myDefault</td>\n</tr>\n</tbody>\n</table>\n\nPlease align your columns in the AsciiDoc source for better readability when editing in text view. If you have a very long description, break at 120 characters and align the text to improve source readability.\n\n**Figure 1. Example in AsciiDoc source for very long table descriptions**\n\nthis is rendered as:\n\n<table>\n<thead>\n<tr>\n<th>Parameter</th>\n<th>Description</th>\n<th>Required</th>\n<th>Default value</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>basic-authentication</td>\n<td>Authentication credentials to perform basic authentication. Credentials should comply to RFC1945 section 11.1, without the Base64 encoding part. That’s: be a string made of the concatenation of: 1- the user ID; 2- a colon; 3- the password. <strong>basic-authentication</strong> takes precedence over the 'user' and 'password' parameters.</td>\n<td>optional</td>\n<td>-</td>\n</tr>\n<tr>\n<td>header[0-9]+</td>\n<td>Additional headers to be sent along with the request. Example of valid parameter’s names are header0, header1 and header180. header is <em>not</em> a valid parameter name.</td>\n<td>optional</td>\n<td>-</td>\n</tr>\n</tbody>\n</table>\n\n### 7.9. Include images\n\nWhen visualizing complex problems use images to help explain and provide greater information. We use two directories for images.\n\nThe image folder structure mirrors the text structure. This makes it easier to locate the AsciiDoc text file where the image is included.\nExample folder structure for image files\n\n- opennms-doc\n - guide-doc\n - README.adoc\n - pom.xml\n - src\n - asciidoc\n - configs\n - poller-configuration.xml\n - images\n - 01_opennms-logo.png\n - 02_pris-overview.png\n - images_src\n - pris-overview.graphml\n - index.adoc\n - text\n - images.adoc\n - include-source.adoc\n - introduction.adoc\n - writing.adoc\n - target\n\n1. This folder contains all documentation modules.\n2. The module for this documentation for target group of documentation contributors.\n3. Indicates a source folder.\n4. The documentation root folder.\n5. Folder for images. Images should be *.png or *.jpg if included in the documentation.\n6. The image used; the format is a leading `<number>_` followed by a name using no spaces.\n7. Some images are created from tools like yED. This folder should contain the editable version of the file with the same file name.\n8. Editable version of the image source file. Note no spaces in the name.\n9. Main document file which includes all documentation parts and is rendered as `index.html` for the web.\n10. AsciIDoc source file which can include images.\n11. Target folder with generated HTML output after `mvn clean package` has been performed.\n\n⚠️ All images in the entire manual share the same namespace, it is therefore best practice to use unique identifiers for images.\n\nTo include an image file, make sure that it resides in the 'images/' directory relative to the document you’re including it in. Then use the following syntax for inclusion in the document:\n7.10. Code Snippets\n\nYou can include code snippets, configuration- or source code files in the documentation. You can enable syntax highlighting by providing the given language parameter. This will work on source code or configuration.\n\n7.10.1. Explicitly defined in the document\n\nBe careful to use this kind of code snippet as sparsely as possible. Code becomes obsolete very quickly; archaic usage practices are detrimental.\n\nIf you do wish to include snippets, use the following method:\n\nThis is a sample configuration explicitly in the documentation\n\n```xml\n<service name=\"DNS\" interval=\"300000\" user-defined=\"false\" status=\"on\">\n <parameter key=\"retry\" value=\"2\" />\n <parameter key=\"timeout\" value=\"5000\" />\n <parameter key=\"port\" value=\"53\" />\n <parameter key=\"lookup\" value=\"localhost\" />\n <parameter key=\"fatal-response-codes\" value=\"2,3,5\" />\n !-- ServFail, NXDomain, Refused -->\n <parameter key=\"rrd-repository\" value=\"/opt/opennms/share/rrd/response\" />\n <parameter key=\"rrd-base-name\" value=\"dns\" />\n <parameter key=\"ds-name\" value=\"dns\" />\n</service>\n```\n\nIf there’s no suitable syntax highlighter for the code used just omit the language: [source].\n\nCurrently the following syntax highlighters are enabled:\n\n- Bash\n- Groovy\nFor other highlighters that could be added see https://code.google.com/p/google-code-prettify/.\n\n7.10.2. Included from an example file\n\nYou can include source or configuration from an external file. In this way you can provide a working example configuration maintaining doc and example at the same time. The procedure and rules are the same as with images: the path is relative to the *.adoc file where the file to be used is included.\n\n**Include complete external file**\n\n```\n[source,xml]\n----\ninclude::*../configs/wmi-config.xml[]\n----\n```\n\nThis is how it’s rendered:\n\n```xml\n<?xml version=\"1.0\"?>\n<wmi-config retry=\"2\" timeout=\"1500\"\n username=\"Administrator\" domain=\"WORKGROUP\" password=\"password\">\n</wmi-config>\n```\n\n7.10.3. Include parts of a file\n\nTo include a specific segment of a large configuration file, assign tags that tell AsciiDoc the section to include. In this example, just the service definition of the ICMP monitor should be included.\n\nIn the 'poller-configuration.xml', tag the section in the following manner:\n<rrd step=\"300\">\n <rra>RRA:AVERAGE:0.5:1:2016</rra>\n <rra>RRA:AVERAGE:0.5:12:1488</rra>\n <rra>RRA:AVERAGE:0.5:288:366</rra>\n <rra>RRA:MAX:0.5:288:366</rra>\n <rra>RRA:MIN:0.5:288:366</rra>\n</rrd>\n\n<!-- # tag::IcmpServiceConfig[] -->\n\n<service name=\"ICMP\" interval=\"300000\" user-defined=\"false\" status=\"on\">\n <parameter key=\"retry\" value=\"2\" />\n <parameter key=\"timeout\" value=\"3000\" />\n <parameter key=\"rrd-repository\" value=\"/opt/opennms/share/rrd/response\" />\n <parameter key=\"rrd-base-name\" value=\"icmp\" />\n <parameter key=\"ds-name\" value=\"icmp\" />\n</service>\n\n<!-- # end::IcmpServiceConfig[] -->\n\n<service name=\"DNS\" interval=\"300000\" user-defined=\"false\" status=\"on\">\n <parameter key=\"retry\" value=\"2\" />\n <parameter key=\"timeout\" value=\"5000\" />\n <parameter key=\"port\" value=\"53\" />\n</service>\n\n7.11. Cheat sheets and additional hints\n\nThe documentation uses the AsciiDoc format. There are a number of guides to help you get started with AsciiDoc:\n7.12. Migrating content from project wiki\n\nThe project wiki contains much information that ought to be migrated to the official documentation set. To help with this effort, we have a wiki template which informs readers of articles that are tagged for migration to the official docs, or that have already been migrated. When you identify an article in the OpenNMS wiki whose information should be migrated (either in its entirety, or just individual sections), use the following process.\n\n1. If you do not already have a wiki account, request one before getting started. Your request must be approved by a wiki admin. If you don't get approved within a day, send a note to the opennms-devel mailing list or on the OpenNMS Development chat channel.\n\n2. Create an issue in the project issue tracker, in project NMS. Note the issue number; you will use it below.\n\n3. After logging in to the wiki, visit the article whose content should be migrated.\n\n4. Click on the Edit Source link at the top of the article view.\n\n5. Add text like the following to the top of the article source editor:\n\n```asciidoc\n{{OfficialDocs | scope=article | guide=admin | issue=NMS-9926 | date=March 2018 | completed=false}}\n```\n\n- The value of the `scope` attribute must be either `article`, if the entire article should be migrated, or `section` if only specific section(s) should be migrated.\n - When using `scope = section`, it's fine to use this template multiple times in a single article.\n- The value of the `guide` attribute must be one of `admin`, `development`, `install`, or `user`.\n - If the information in an article should be migrated to multiple official guides, use multiple instances of the `{{OfficialDocs}}` template; try to target these by section when possible.\n- The value of the `issue` parameter must be a valid issue ID in the project issue tracker, and will become a live link.\n• The value of the `date` parameter should be the month and year when the tag was added, e.g. March 2018.\n\n• The `completed` parameter is optional; it is assumed to be false if omitted, or true if its value is either `true` or `yes`.\n\n---\n\n**Editing Event Configuration How-To**\n\n```wiki\n{{OfficialDocs | scope=article | guide=admin | issue=NMS-9926 | date=March 2018}}\n```\n\nFigure 3. Wiki source editor with example **OfficialDocs** template usage\n\n6. Enter an edit summary such as **Tagged for migration to official docs**, NMS-12345 and click **Show preview**\n\n7. After verifying that your changes render as expected (see image), click **Save changes**.\n\nFigure 4. Rendering of **OfficialDocs** wiki template on an article pending migration\n\n8. Migrate the information, making sure to follow the guidelines laid out earlier in this section; do not just copy and paste, and watch out for obsolete information. If you need help, contact the developers through one of the methods mentioned above.\n\n9. Once the migration is complete and the issue is closed, edit the wiki article again and change `completed=false` to `completed=true`.\n\n10. The rendering of the template will change to indicate that the migration has been completed.\n\nFigure 5. Rendering of **OfficialDocs** wiki template on an article whose migration is completed\n\nAdding the `{{OfficialDocs}}` template to an article will implicitly add that article to a pair of wiki categories:\n\n- **Migration to official docs pending** or **Migration to official docs completed**, according to the value of the `completed` attribute\n- **Migrate to X guide**, according to the value of the `guide` attribute\nChapter 8. AMQP Integration\n\nThe AMQP Integration allows external systems to communicate with the event bus of OpenNMS Horizon and receive alarms via the AMQP protocol.\n\nAMQP is standard messaging protocol supported by a number of brokers including ActiveMQ and QPID.\n\nThe integration is written using Camel + OSGi and has the following components:\n\n- Event Forwarder\n- Event Receiver\n- Alarm Northbounder\n\nCustom filtering (i.e. which events to forward) and transformations (i.e. how the events are represented in the messages) can be used in each of the components. Generic implementations of each component can be configured and setup independently, i.e. you can choose to only forward alarms.\n\n8.1. Event Forwarder\n\nThe event forwarder listens for all events on the internal event bus of OpenNMS Horizon. Events from the bus are sent to a Camel processor, which can filter or transform these, before being sent to the AMQP endpoint.\n\nThe event forwarder exposes the following properties via the org.opennms.features.amqp.eventforwarder pid:\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Default</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>connectionUrl</td>\n<td>amqp://localhost:5672</td>\n<td>Used by the JmsConnectionFactory. See AMQP for details.</td>\n</tr>\n<tr>\n<td>username</td>\n<td>guest</td>\n<td>Username</td>\n</tr>\n<tr>\n<td>password</td>\n<td>guest</td>\n<td>Password</td>\n</tr>\n<tr>\n<td>destination</td>\n<td>amqp:topic:opennms-events</td>\n<td>Target queue or topic. See AMQP for details.</td>\n</tr>\n<tr>\n<td>processorName</td>\n<td>default-event-forwarder-processor</td>\n<td>Named org.apache.camel.Processor implementation used to filter and/or format the events.</td>\n</tr>\n</tbody>\n</table>\n\nThe default processor, the default-event-forwarder-processor, marshalls events to XML and does...\nnot perform any filtering. This means that when enabled, all events will be forwarded to the AMQP destination with XML strings as the message body.\n\n### 8.1.1. Setup\n\nStart by logging into a Karaf shell.\n\nUpdate the properties with your deployment specific values:\n\n```bash\nconfig:edit org.opennms.features.amqp.eventforwarder\nconfig:property-set connectionUrl amqp://localhost:5672\nconfig:property-set destination amqp:topic:opennms-events\nconfig:property-set processorName default-event-forwarder-processor\nconfig:update\n```\n\nInstall the feature:\n\n```bash\nfeature:install opennms-amqp-event-forwarder\n```\n\n### 8.1.2. Debugging\n\nYou can get detailed information on the Camel route using:\n\n```bash\ncamel:route-info forwardEvent\n```\n\n### 8.2. Event Receiver\n\nThe event receiver listens for messages from an AMQP target and forwards them onto the internal event bus of OpenNMS Horizon. Messages are sent to a Camel processor, which can filter or transform these, before being sent onto the event bus.\n\nThe event receiver exposes the following properties via the `org.opennms.features.amqp.eventreceiver` pid:\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Default</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>connectionUrl</td>\n<td>amqp://localhost:5672</td>\n<td>Used by the JmsConnectionFactory. See AMQP for details.</td>\n</tr>\n<tr>\n<td>username</td>\n<td>guest</td>\n<td>Username</td>\n</tr>\n<tr>\n<td>password</td>\n<td>guest</td>\n<td>Password</td>\n</tr>\n<tr>\n<td>source</td>\n<td>amqp:queue:opennms-events</td>\n<td>Source queue or topic. See AMQP for details.</td>\n</tr>\n</tbody>\n</table>\nThe default processor, the `default-event-receiver-processor`, expects the message bodies to contain XML strings which are it unmarshalls to events.\n\n### 8.2.1. Setup\n\nStart by logging into a Karaf shell.\n\nUpdate the properties with your deployment specific values:\n\n```\nconfig:edit org.opennms.features.amqp.eventreceiver\nconfig:property-set connectionUrl amqp://localhost:5672\nconfig:property-set source amqp:queue:opennms-events\nconfig:property-set processorName default-event-receiver-processor\nconfig:update\n```\n\nInstall the feature:\n\n```\nfeature:install opennms-amqp-event-receiver\n```\n\n### 8.2.2. Debugging\n\nYou can get detailed information on the Camel route using:\n\n```\ncamel:route-info receiveEvent\n```\n\n### 8.3. Alarm Northbounder\n\nThe alarm northbounder listens for all northbound alarms. Alarms are sent to a Camel processor, which can filter or transform these, before being sent to the AMQP endpoint.\n\nThe alarm northbounder exposes the following properties via the `org.opennms.features.amqp.alarmnorthbounder` pid:\n\n<table>\n<thead>\n<tr>\n<th>Property</th>\n<th>Default</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>connectionUrl</td>\n<td>amqp://localhost:5672</td>\n<td>Used by the JmsConnectionFactory. See AMQP for details.</td>\n</tr>\n<tr>\n<td>Property</td>\n<td>Default</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>---------------</td>\n<td>--------------</td>\n<td>------------------------------------------------------------------------------</td>\n</tr>\n<tr>\n<td>username</td>\n<td>guest</td>\n<td>Username</td>\n</tr>\n<tr>\n<td>password</td>\n<td>guest</td>\n<td>Password</td>\n</tr>\n<tr>\n<td>destination</td>\n<td>amqp:topic:opennms-alarms</td>\n<td>Target queue or topic. See <a href=\"#\">AMQP</a> for details.</td>\n</tr>\n<tr>\n<td>processorName</td>\n<td>default-alarm-northbounder-processor</td>\n<td>Named <a href=\"#\">org.apache.camel.Processor</a> implementation used to filter and/or format the alarms.</td>\n</tr>\n</tbody>\n</table>\n\nThe default processor, the `default-alarm-northbounder-processor`, converts the alarms to a string and does not perform any filtering. This means that when enabled, all alarms will be forwarded to the AMQP destination with strings as the message body.\n\n### 8.3.1. Setup\n\nStart by logging into a Karaf shell.\n\nUpdate the properties with your deployment specific values:\n\n```java\nconfig:edit org.opennms.features.amqp.alarmnorthbounder\nconfig:property-set connectionUrl amqp://localhost:5672\nconfig:property-set destination amqp:topic:opennms-alarms\nconfig:property-set processorName default-alarm-northbounder-processor\nconfig:update\n```\n\nInstall the feature:\n\n```bash\nfeature:install opennms-amqp-alarm-northbounder\n```\n\n### 8.3.2. Debugging\n\nYou can get detailed information on the Camel route using:\n\n```bash\ncamel:route-info forwardAlarm\n```\n\n### 8.4. Custom Processors\n\nIf your integration requires specific filtering and or formatting, you can write your own processor by implementing the `org.apache.camel.Processor` interface.\n\nFor example, we can implement a custom processor used for event forwarding:\nimport org.apache.camel.Exchange;\nimport org.apache.camel.Processor;\n\npublic class MyEventProcessor implements Processor {\n @Override\n public void process(final Exchange exchange) throws Exception {\n final Event event = exchange.getIn().getBody(Event.class);\n\n // Filtering\n if (!shouldForward(event)) {\n exchange.setProperty(Exchange.ROUTE_STOP, Boolean.TRUE);\n return;\n }\n\n // Transforming\n MyDTO eventAsDTO = toDTO(event);\n exchange.getIn().setBody(eventAsDTO, MyDTO.class);\n }\n}\n\nIn order to use the processor, package it as a bundle, and expose it to the OSGi service registry using:\n\n```xml\n<bean id=\"myEventProcessor\" class=\"org.opennms.integrations.evilcorp.MyEventProcessor\" />\n\n<service id=\"myEventProcessorService\" ref=\"myEventProcessor\" interface=\"org.apache.camel.Processor\">\n <service-properties>\n <entry key=\"name\" value=\"evilcorp-event-forwarder-processor\"/>\n </service-properties>\n</service>\n```\n\nOnce your bundle in the Karaf container, you can update the loaded you can refer to your processor with:\n\n```\nconfig:edit org.opennms.features.amqp.eventforwarder\nconfig:property-set processorName evilcorp-event-forwarder-processor\nconfig:update\n```\n\nIf the event forwarder feature was already started, it should automatically restart and start using the new processor. Otherwise, you can start the feature with:\n\n```\nfeature:install opennms-amqp-event-forwarder\n```\nChapter 9. Design and Styleguidelines\n\n\nBuilding and contributing JasperReports is a way to contribute to the project. To make it easier to maintain and style reports the following layout guideline can be used to have similar and more consistent report layout.\n\n\n\n**Figure 6. Layout for creating JasperReports**\n\nThe following formatting can be applied:\n\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Convention</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Date</td>\n<td>yyyy/MM/dd HH:mm:ss</td>\n</tr>\n<tr>\n<td>Report Range</td>\n<td>Report Begin: ${startDate} Report End: ${endDate}</td>\n</tr>\n<tr>\n<td>Paging</td>\n<td>Page ${current} of ${total}</td>\n</tr>\n</tbody>\n</table>\n\nBased on this template definition there exist a [GitHub repository](https://github.com) which contains a JasperReport template."}}},{"rowIdx":98,"cells":{"id":{"kind":"string","value":"2c929723d78647863c1620bdb92d2b99a26f89ba"},"text":{"kind":"string","value":"Software Program\n\nSoftware Management Guidebook\n\nNovember 1996\nForeword\n\nThis document is a product of the National Aeronautics and Space Administration (NASA) Software Program, an Agency-wide program to promote continual improvement of software engineering within NASA. The goals and strategies for this program are documented in the NASA Software Strategic Plan, July 13, 1995.\n\n# Table of Contents\n\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Foreword</td>\n<td>iii</td>\n</tr>\n<tr>\n<td>1. Introduction</td>\n<td>1</td>\n</tr>\n<tr>\n<td>1.1 Background</td>\n<td>1</td>\n</tr>\n<tr>\n<td>1.2 Purpose</td>\n<td>1</td>\n</tr>\n<tr>\n<td>1.3 Scope</td>\n<td>2</td>\n</tr>\n<tr>\n<td>1.4 Overview</td>\n<td>2</td>\n</tr>\n<tr>\n<td>1.4.1 Organization</td>\n<td>2</td>\n</tr>\n<tr>\n<td>1.4.2 Terminology</td>\n<td>2</td>\n</tr>\n<tr>\n<td>1.4.3 Notation</td>\n<td>2</td>\n</tr>\n<tr>\n<td>2. Software Engineering Process Requirements and Infrastructure</td>\n<td>5</td>\n</tr>\n<tr>\n<td>2.1 General Requirements</td>\n<td>5</td>\n</tr>\n<tr>\n<td>2.2 Specific Required Activities and Products</td>\n<td>6</td>\n</tr>\n<tr>\n<td>2.2.1 Management Activities</td>\n<td>8</td>\n</tr>\n<tr>\n<td>2.2.2 Technical Activities</td>\n<td>8</td>\n</tr>\n<tr>\n<td>2.2.3 Software Process Improvement Activities</td>\n<td>8</td>\n</tr>\n<tr>\n<td>2.2.4 System-Level Considerations</td>\n<td>8</td>\n</tr>\n<tr>\n<td>2.3 Software Process Responsibilities</td>\n<td>10</td>\n</tr>\n<tr>\n<td>2.3.1 Level 1: NASA Headquarters, IV&V Facility, and Software Working Group</td>\n<td>11</td>\n</tr>\n<tr>\n<td>2.3.2 Level 2: Center and Intra-Center Elements</td>\n<td>12</td>\n</tr>\n<tr>\n<td>2.3.3 Level 3: Branches and Software Projects</td>\n<td>12</td>\n</tr>\n<tr>\n<td>2.4 Process Assets</td>\n<td>13</td>\n</tr>\n<tr>\n<td>3. The Software Project’s Process</td>\n<td>15</td>\n</tr>\n<tr>\n<td>3.1 The Five-Step Project Process</td>\n<td>15</td>\n</tr>\n<tr>\n<td>3.2 Documenting the Project’s Process—The Software Plan</td>\n<td>17</td>\n</tr>\n<tr>\n<td>4. Beginning to Plan the Project: Understanding the Scope of Work</td>\n<td>21</td>\n</tr>\n<tr>\n<td>4.1 Ascertaining Customer Requirements and Constraints</td>\n<td>21</td>\n</tr>\n<tr>\n<td>4.2 Ascertaining Customer Goals and Objectives</td>\n<td>22</td>\n</tr>\n<tr>\n<td>4.3 Understanding Management’s Risk Tolerance</td>\n<td>23</td>\n</tr>\n<tr>\n<td>4.4 Understanding Products to be Delivered and Their Characteristics</td>\n<td>23</td>\n</tr>\n<tr>\n<td>4.4.1 Documentation</td>\n<td>23</td>\n</tr>\n<tr>\n<td>4.4.2 Software Product Releases</td>\n<td>23</td>\n</tr>\n<tr>\n<td>4.4.3 Milestone Reviews</td>\n<td>24</td>\n</tr>\n<tr>\n<td>5. Defining the Technical Approach</td>\n<td>25</td>\n</tr>\n<tr>\n<td>5.1 Selecting an Appropriate Life-Cycle Model</td>\n<td>26</td>\n</tr>\n</tbody>\n</table>\n6. Finishing the Software Plan—Defining the Management Approach .................................................. 75\n 6.1 Establishing the Software Project’s Organizational Structure .................................................. 76\n 6.2 Estimating and Scheduling the Work ....................................................................................... 77\n 6.3 Planning Other Activities ......................................................................................................... 80\n 6.4 Reviewing the Software Plan .................................................................................................. 83\n7. Running the Project ....................................................................................................................... 85\n 7.1 Managing the Project ................................................................................................................ 86\n 7.1.1 Preparing the Software Team ......................................................................................... 86\n 7.1.2 Monitoring and Controlling the Project .......................................................................... 87\n 7.1.3 Communicating with Stakeholders ................................................................................. 88\n 7.1.4 Maintaining the Software Plan ...................................................................................... 90\n 7.1.5 Keeping Project Records ............................................................................................... 91\n 7.2 Closing Out the Project ............................................................................................................. 92\nAppendix A. Glossary ........................................................................................................................... 95\nAppendix B. Building for Reuse ......................................................................................................... 101\nAppendix C. COTS, GOTS, Reused, and Other NDI Software Products ............................................. 103\n C.1 COTS Software Products ....................................................................................................... 103\n C.2 Evaluating COTS, GOTS, Reused, and Other NDI Software Products .................................. 105\n C.3 Guidelines for Performing Required Activities Involving COTS, GOTS, Reused, and Other NDI Software Products ................................................................................................................. 106\nAppendix D. System-Level Considerations ....................................................................................... 109\n D.1 System Requirements Analysis .............................................................................................. 109\n D.2 System Design ......................................................................................................................... 109\n D.3 Software CI and Hardware CI Integration and Testing .......................................................... 110\n D.4 System Qualification Testing ................................................................................................. 110\n# Figures\n\n<table>\n<thead>\n<tr>\n<th>Figure</th>\n<th>Description</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>2-1</td>\n<td>Required Software Process Activities</td>\n<td>6</td>\n</tr>\n<tr>\n<td>2-2</td>\n<td>System Life Cycle</td>\n<td>9</td>\n</tr>\n<tr>\n<td>2-3</td>\n<td>Software Development Context</td>\n<td>10</td>\n</tr>\n<tr>\n<td>2-4</td>\n<td>Software Maintenance or Enhancement Context</td>\n<td>10</td>\n</tr>\n<tr>\n<td>3-1</td>\n<td>The Five-Step Project Process</td>\n<td>16</td>\n</tr>\n<tr>\n<td>3-2</td>\n<td>Planning the Software Project</td>\n<td>18</td>\n</tr>\n<tr>\n<td>3-3</td>\n<td>Tailoring the Project’s Software Process</td>\n<td>20</td>\n</tr>\n<tr>\n<td>5-1</td>\n<td>Phases and Activities</td>\n<td>26</td>\n</tr>\n<tr>\n<td>5-2</td>\n<td>Waterfall Development Life-Cycle Model</td>\n<td>29</td>\n</tr>\n<tr>\n<td>5-3</td>\n<td>Incremental Development Life-Cycle Model</td>\n<td>31</td>\n</tr>\n<tr>\n<td>5-4</td>\n<td>Evolutionary Development Life-Cycle Model</td>\n<td>33</td>\n</tr>\n<tr>\n<td>5-5</td>\n<td>Package-Based Development Life-Cycle Model</td>\n<td>35</td>\n</tr>\n<tr>\n<td>5-6</td>\n<td>Legacy System Maintenance Life-Cycle Model</td>\n<td>36</td>\n</tr>\n<tr>\n<td>5-7</td>\n<td>Primary Software Engineering Activities</td>\n<td>39</td>\n</tr>\n<tr>\n<td>5-8</td>\n<td>Software Engineering Support Activities</td>\n<td>39</td>\n</tr>\n<tr>\n<td>6-1</td>\n<td>Typical Software Project Organization</td>\n<td>76</td>\n</tr>\n<tr>\n<td>7-1</td>\n<td>Running the Project</td>\n<td>85</td>\n</tr>\n<tr>\n<td>7-2</td>\n<td>Product Handovers</td>\n<td>89</td>\n</tr>\n<tr>\n<td>B-1</td>\n<td>High-Reuse Life-Cycle Model</td>\n<td>102</td>\n</tr>\n</tbody>\n</table>\n# Tables\n\n<table>\n<thead>\n<tr>\n<th>Table</th>\n<th>Description</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Table 1-1</td>\n<td>Use of Icons</td>\n<td>3</td>\n</tr>\n<tr>\n<td>Table 2-1</td>\n<td>Required Activities, Products, and Roles</td>\n<td>7</td>\n</tr>\n<tr>\n<td>Table 2-2</td>\n<td>Sampling of Software Products at Each Organizational Level</td>\n<td>11</td>\n</tr>\n<tr>\n<td>Table 3-1</td>\n<td>Mapping the Five-Step Project Process to This Guidebook</td>\n<td>15</td>\n</tr>\n<tr>\n<td>Table 4-1</td>\n<td>Sample Project Objectives</td>\n<td>22</td>\n</tr>\n<tr>\n<td>Table 5-1</td>\n<td>Defining a Life Cycle</td>\n<td>27</td>\n</tr>\n<tr>\n<td>Table 5-2</td>\n<td>Summary of Waterfall Development Life-Cycle Model</td>\n<td>28</td>\n</tr>\n<tr>\n<td>Table 5-3</td>\n<td>Products and Milestone Reviews for the Waterfall Development Life-Cycle Model</td>\n<td>29</td>\n</tr>\n<tr>\n<td>Table 5-4</td>\n<td>Summary of Incremental Development Life-Cycle Model</td>\n<td>30</td>\n</tr>\n<tr>\n<td>Table 5-5</td>\n<td>Products and Milestone Reviews for the Incremental Development Life-Cycle Model</td>\n<td>31</td>\n</tr>\n<tr>\n<td>Table 5-6</td>\n<td>Summary of Evolutionary Development Life-Cycle Model</td>\n<td>32</td>\n</tr>\n<tr>\n<td>Table 5-7</td>\n<td>Products and Milestone Reviews for the Evolutionary Development Life-Cycle Model</td>\n<td>33</td>\n</tr>\n<tr>\n<td>Table 5-8</td>\n<td>Summary of Package-Based Development Life-Cycle Model</td>\n<td>34</td>\n</tr>\n<tr>\n<td>Table 5-9</td>\n<td>Major Products and Milestone Reviews for the Package-Based Development Life-Cycle Model</td>\n<td>35</td>\n</tr>\n<tr>\n<td>Table 5-10</td>\n<td>Summary of Legacy System Maintenance Life-Cycle Model</td>\n<td>36</td>\n</tr>\n<tr>\n<td>Table 5-11</td>\n<td>Products and Milestone Reviews for the Legacy System Maintenance Life-Cycle Model</td>\n<td>37</td>\n</tr>\n<tr>\n<td>Table 5-12</td>\n<td>Structured Requirements Analysis Method</td>\n<td>41</td>\n</tr>\n<tr>\n<td>Table 5-13</td>\n<td>Object-Oriented Requirements Analysis Method</td>\n<td>42</td>\n</tr>\n<tr>\n<td>Table 5-14</td>\n<td>Prototyping Technique</td>\n<td>43</td>\n</tr>\n<tr>\n<td>Table 5-15</td>\n<td>JAD Workshop Technique</td>\n<td>44</td>\n</tr>\n<tr>\n<td>Table 5-16</td>\n<td>Structured Design Method</td>\n<td>46</td>\n</tr>\n<tr>\n<td>Table 5-17</td>\n<td>Object-Oriented Design Method</td>\n<td>46</td>\n</tr>\n<tr>\n<td>Table 5-18</td>\n<td>Top-Down Method</td>\n<td>51</td>\n</tr>\n<tr>\n<td>Table 5-19</td>\n<td>Bottom-Up Method</td>\n<td>51</td>\n</tr>\n<tr>\n<td>Table 5-20</td>\n<td>Functional Path Method</td>\n<td>52</td>\n</tr>\n<tr>\n<td>Table 5-21</td>\n<td>Software Product V&V Summary</td>\n<td>57</td>\n</tr>\n</tbody>\n</table>\nTable 5-22. Inspection Method ........................................................................................................... 58\nTable 5-23. Walkthrough Method ........................................................................................................ 58\nTable 5-24. Document Review Method ............................................................................................... 59\nTable 5-25. Demonstration Method ..................................................................................................... 59\nTable 5-26. Functional Testing Method ............................................................................................... 60\nTable 5-27. Structural or Coverage Testing Method ............................................................................. 61\nTable 5-28. Statistical Testing Method ................................................................................................. 61\nTable 5-29. Regression Testing Method ................................................................................................ 62\nTable 5-30. Testing Methods vs. Testing Levels ................................................................................... 62\nTable 5-31. The Cleanroom Method .................................................................................................... 63\nTable 5-32. Candidate Milestone Reviews ......................................................................................... 70\nTable 5-33. Meetings ........................................................................................................................... 71\nTable 5-34. Presentations ....................................................................................................................... 71\nTable 5-35. Demonstrations .................................................................................................................. 72\nTable 6-1. Three Levels of Estimates and Plans .................................................................................... 77\nTable 6-2. Mini-Waterfall ...................................................................................................................... 78\nTable 6-3. Timeboxes ............................................................................................................................ 79\nTable 6-4. Required Activities and Related Measures .......................................................................... 81\nTable 6-5. Process Studies ..................................................................................................................... 82\nTable 7-1. Recommended Status Reports and Meetings ....................................................................... 88\nTable C-1. Guidelines for Using COTS, GOTS, Reused, and Other NDI Software Products............ 107\n1. Introduction\n\n1.1 Background\n\nThe objective of every National Aeronautics and Space Administration (NASA) software engineering project is to provide, to the customer, a software product that is engineered to satisfy the customer’s requirements, within determined cost, schedule, and quality guidelines.\n\nThe term software engineering encompasses new development, modification, reuse, re-engineering, maintenance, and all other activities resulting in software products. Throughout NASA, organizations engineer software products that cover a wide spectrum of characteristics (Reference 1):\n\n- Application domains include flight and embedded software, mission ground support software, general support software, science analysis software, research software, and administrative and Information Resources Management (IRM) software.\n- Target operating environments encompass PC-based, mainframe-based, workstation-based, and client/server-based solutions.\n- Product sizes range from only a few thousand lines of code to more than a million.\n- Cost and cycle-time requirements vary.\n- Desired end-product qualities—reusability, commercialization, and consequences of software failure (from minor inconvenience to loss of a mission or loss of life)—also vary.\n\nOne significant lesson learned from many years of software engineering throughout NASA is that no single solution can solve every problem. No one life-cycle model, analysis and design method, testing method, product evaluation method, or degree of formality for documents and reviews is appropriate for all NASA software projects. To accommodate these variations, each project must tailor its software process to acknowledge customer requirements and constraints; goals and objectives for cost, cycle time, and product qualities; and management’s tolerance for risk. Such tailoring is the responsibility of the project’s software manager.\n\n1.2 Purpose\n\nThe purpose of this NASA Software Management Guidebook is twofold. First, this document defines the core products and activities required of NASA software projects. It defines life-cycle models and activity-related methods but acknowledges that no single life-cycle model is appropriate for all NASA software projects. It also acknowledges that the appropriate method for accomplishing a required activity depends on characteristics of the software project.\n\nSecond, this guidebook provides specific guidance to software project managers and team leaders in selecting appropriate life cycles and methods to develop a tailored plan for a software engineering project.\n1.3 Scope\n\nThis handbook addresses the engineering of software products, where those products either (1) comprise a software system for which this handbook governs the overall engineering effort or (2) are part of a hardware-software system for which this handbook governs only the software portion.\n\nSystem engineering management issues are outside of the scope of this guidebook. Section 2.2.4 places the software life cycle in the context of the system life cycle, and Appendix Appendix D. discusses the system-level considerations required of the software manager and team members.\n\nThis book also does not cover acquisition of software products; it covers development and maintenance.\n\n1.4 Overview\n\n1.4.1 Organization\n\nChapter 2 of this guidebook summarizes the common elements of the overall NASA software engineering process. Chapters 3 through 6 describe the NASA software engineering process in somewhat more detail, including summary descriptions of required activities and products, and recommended methods for performing those activities. Chapter 7 discusses running and then closing out software projects.\n\nAppendix Appendix A. is a glossary of software engineering terms that every software project manager should understand. Appendix Appendix B. provides guidance for building software components with reusability in mind. Appendix Appendix C. provides more detailed guidance for incorporating non-developed items (NDIs) into software products. Appendix Appendix D. lists additional considerations when the software under development is only part of a larger system.\n\n1.4.2 Terminology\n\nSeveral terms have specific meanings in this document. These terms are used consistently to emphasize and ensure understanding of the flexibility built into the software process common requirements. Please refer to the glossary in Appendix Appendix A. for definitions and discussion of the following key sets of terms:\n\n- Development, maintenance, enhancement\n- Life-cycle models, phases, activities, methods\n- Software configuration items (CIs), systems\n- Documentation, record\n\n1.4.3 Notation\n\nTable I–1 explains the use of icons in this guidebook.\n<table>\n<thead>\n<tr>\n<th>Icon</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>!!</td>\n<td>A double exclamation mark highlights related tips that have been shown effective on NASA programs.</td>\n</tr>\n<tr>\n<td>✔</td>\n<td>A check mark highlights required software engineering activities.</td>\n</tr>\n<tr>\n<td>⚪issors</td>\n<td>A pair of scissors highlights software process tailoring information; that is, methods and techniques proven to be effective on NASA programs and recommended for use in performing a particular activity.</td>\n</tr>\n</tbody>\n</table>\n2. Software Engineering Process Requirements and Infrastructure\n\nThis chapter summarizes the common aspects of the overall NASA software engineering process. The first two sections discuss key activities and products that are expected of NASA software projects. The third section discusses the roles and responsibilities of personnel at various organizational levels. The final section introduces the concept of a process asset library (PAL).\n\n2.1 General Requirements\n\nEvery software project must meet a number of general requirements in carrying out the detailed required activities, for example\n\n- The software team uses systematic, documented methods for all software engineering activities. These methods are described or referenced in the project’s software plan.\n- The software team applies standards for representing requirements; design; code; test plans, procedures, and results; and other software products. These standards are described or referenced in the software plan.\n- During the course of the project, the software team identifies and evaluates NDIs, including commercial-off-the-shelf (COTS), government-off-the-shelf (GOTS), and reusable software products, as well as software products not created by project personnel (for example, by other NASA or contractor personnel), for use in fulfilling the project requirements. The scope of the search and the criteria to be used for evaluation are as described in the software plan. Software products that meet the criteria are used where practical. Incorporated software products must meet applicable data rights and licensing requirements. Appendix Appendix C. discusses an approach for developing systems that comprise predominantly NDI components.\n- During the course of the project, the software team identifies opportunities for developing software products for reuse and evaluates the benefits and costs of these opportunities. Opportunities that provide cost benefits and are compatible with the customer’s objectives are identified to the customer. The software requirements might also state that the software team develop software products specifically for reuse.\n- The software team identifies critical software CIS (or portions thereof) and develops and implements a strategy that addresses the following critical issues:\n - System resource utilization: critical system resource capacities or constraints are imposed on the final product\n - Safety: failure of the software could lead to a hazardous state\n - Security: failure could lead to a breach of system security\n - Privacy: failure could lead to a breach of system privacy\n - Other critical characteristics\nThe software team develops an appropriate strategy for such software, including tests and analyses, to ensure that the requirements, design, implementation, and operating procedures for the identified software minimize or eliminate the potential for hazardous or compromising conditions. The software team records the strategy in the software plan, implements the strategy, and produces evidence, as part of required software records, that the defined strategy has been carried out successfully.\n\n- The software team records rationale that will be useful to the software operations and maintenance (O&M) organization for key decisions made in specifying, designing, implementing, and testing the software. The rationale includes trade-offs considered, analysis methods, and other criteria used to make the decisions. The rationale is recorded in documents, code comments, or other media that are transferable to the software O&M organization.\n\n### 2.2 Specific Required Activities and Products\n\nThe software manager establishes a project software engineering process that is based on the NASA software process and consistent with the software requirements. The NASA software process comprises three categories of activities:\n\n1. Management\n2. Technical\n3. Software process improvement\n\nFigure 2–1 illustrates the relationships among the activities; Table 2–1 summarizes the activities and the primary products generated as a result of performing each activity.\n\n<table>\n<thead>\n<tr>\n<th>Develop initial project software plan</th>\n<th>Close out software project products</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>Monitor and control software project (maintain project software plan and records as necessary)</td>\n</tr>\n<tr>\n<td></td>\n<td>Prepare software team</td>\n</tr>\n<tr>\n<td></td>\n<td>Independently assure software products and activities (SQA)</td>\n</tr>\n<tr>\n<td></td>\n<td>Manage configuration (SCM)</td>\n</tr>\n<tr>\n<td></td>\n<td>Participate in milestone reviews</td>\n</tr>\n<tr>\n<td></td>\n<td>Validate and verify (V&V) software products</td>\n</tr>\n<tr>\n<td>Perform required technical activities (i.e., software CI requirements definition and analysis through qualification testing, including interim deliveries) until final product is delivered</td>\n<td>Deliver final software products</td>\n</tr>\n</tbody>\n</table>\n\n**Figure 2–1. Required Software Process Activities**\n<table>\n<thead>\n<tr>\n<th>Activity</th>\n<th>Primary Products</th>\n<th>Key Roles</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Software project planning</td>\n<td>• Software plan<br>• Project planning review</td>\n<td>• Software manager<br>• Software team leader<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software CI requirements definition and analysis</td>\n<td>• Software CI requirements specification<br>• V&V records for requirements definition and analysis products<br>• Software requirements milestone review</td>\n<td>• Software requirements analyst<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software CI design</td>\n<td>• Software CI design specification<br>• V&V records for design products<br>• Software design milestone review</td>\n<td>• Software design architect<br>• Software detail designer<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software CI implementation and testing</td>\n<td>• Unit-level design<br>• Implementation test plans, procedures<br>• Implemented, integrated, tested software<br>• V&V records for implementation and testing products<br>• Qualification test readiness milestone review</td>\n<td>• Software implementer<br>• Software unit tester<br>• Software integrator and tester<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software CI qualification testing</td>\n<td>• Qualification test plan, procedures<br>• Qualification tested software<br>• V&V records for qualification testing products</td>\n<td>• Software qualification tester<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Preparation for software delivery</td>\n<td>• Executable software<br>• Software source files<br>• Version description<br>• As-built software description<br>• Software user’s guide</td>\n<td>• Software configuration manager<br>• Rest of software team<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software project close-out</td>\n<td>• Software project history<br>• Software project lessons learned and recommendations for improvement<br>• Software project close-out data</td>\n<td>• Software manager<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software product validation and verification (V&V)</td>\n<td>• Software product V&V records</td>\n<td>• Software team<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software configuration management</td>\n<td>• Software configuration management plan (part of the software plan)<br>• Controlled software products<br>• Software configuration management records</td>\n<td>• Software configuration manager<br>• Rest of software team<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software quality assurance</td>\n<td>• Software quality assurance plan (part of the software plan)<br>• Software quality assurance records</td>\n<td>• Software QA representative</td>\n</tr>\n<tr>\n<td>Milestone reviews</td>\n<td>• Milestone reviews</td>\n<td>• Software manager<br>• Rest of software team<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software team preparation</td>\n<td>• Training records</td>\n<td>• Software manager<br>• Rest of software team<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Project monitoring and controlling</td>\n<td>• Management indicators<br>• Project status reviews</td>\n<td>• Software manager<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>Software process improvement</td>\n<td>• Software technology study plans and study results<br>• Defect causal analysis recommendations</td>\n<td>• Entire software team<br>• Software QA representative</td>\n</tr>\n<tr>\n<td>System-level considerations</td>\n<td>• System and operations concept, operational scenarios<br>• System requirements specification<br>• System design specification<br>• Hardware and software CI integration and test plan, procedures<br>• System qualification test plan, procedures<br>• Qualification tested system<br>• V&V records for qualification testing products</td>\n<td>• Entire software team<br>• Software QA representative</td>\n</tr>\n</tbody>\n</table>\n2.2.1 Management Activities\n\nThe following are required management-related activities:\n\n- Software project planning\n- Software team preparation\n- Software project monitoring and control\n- Software project close-out\n\n2.2.2 Technical Activities\n\nThe following are required technical activities, each of which produces one or more specific software products. They may overlap, may be applied iteratively, may be applied differently to different elements of software, and are not necessarily performed in the order listed. (Remember that activities are not synonymous with phases. Refer to the Glossary (Appendix Appendix A.) for definitions and discussion regarding activities versus phases.)\n\n- Software CI requirements definition and analysis\n- Software CI design\n- Software CI implementation and testing\n- Software CI qualification testing\n- Preparation for software delivery\n\nThe following are required support activities that are performed in conjunction with each of the above technical activities:\n\n- Software product validation and verification (V&V)\n- Milestone reviews\n- Software configuration management (SCM)\n- Software quality assurance (SQA)\n\n2.2.3 Software Process Improvement Activities\n\nEvery software project presents an opportunity to study and improve the software process. One mechanism used in the NASA software process improvement program is to study the application of new technologies. Process studies are conducted any time an unproven life-cycle or activity-related method is selected by the software manager. The NASA Software Process Improvement Guidebook (Reference 2) describes the approach NASA uses to study and understand the effects of new technologies on software products and processes.\n\n2.2.4 System-Level Considerations\n\nFigure 2–2 illustrates the concept of a system life cycle. This section clarifies some terms related to the system life cycle.\n\n---\n\n1 A “new” technology is one that has not been proven to be effective in practice in a particular NASA application area or domain. It may have been proven effective elsewhere, however.\nIn this guidebook, the term system refers to the operational entity that the organization is responsible for developing, maintaining, or enhancing. That is, if the organization is responsible for developing several software and hardware CIs and is responsible for integrating them into an operational entity, then the collection of those CIs is the system. If, however, the organization is responsible for developing a single software CI, which may be integrated into (for example) a ground support system by a different NASA organization, then the software CI itself is the system referred to in this guidebook.\n\nSome of the systems that NASA organizations develop, or maintain and enhance, include multiple CIs. There may be a mix of software CIs and hardware CIs, or the system may be only hardware or only software. This guidebook discusses the activities associated with the development and with the maintenance and enhancement of the software CI elements of a system, but also includes very high-level summaries of the relevant system-level activities to help the reader understand the context in which the software effort may take place. When the system comprises only software CIs, then most of the system- and CI-level products are one and the same.\n\nDevelopment (see Figure 2–3) is the creation and installation of an operational system that meets an initially defined set of system requirements. Once the system is operational, subsequent changes are considered maintenance or enhancement (see Figure 2–4). Many of the maintenance and enhancement activities are the same or similar to those used in development. The NASA software process applies equally to development and to maintenance and enhancement efforts. (The figures reflect the software emphasis of this guidebook.)\nWhen the software being engineered is a part of a larger system, additional system-level considerations may need to be taken into account. Appendix D addresses those considerations.\n\n2.3 Software Process Responsibilities\n\nThe subsections that follow summarize the basic responsibilities for maintaining and using the NASA software process at the various organizational levels. Table 2-2 provides examples of software process-related products at each level.\nTable 2-2. Sampling of Software Products at Each Organizational Level\n\n<table>\n<thead>\n<tr>\n<th>Level</th>\n<th>Products</th>\n</tr>\n</thead>\n</table>\n| 1 Headquarters, IV&V Facility, and Software Working Group | - NASA Software Strategic Plan \n- This Software Management Guidebook \n- Other agency-wide software engineering (management, development, and assurance) guidebooks, plans, policies, and standards \n- Domain guidance \n- Independent in-progress assessments of high-profile development projects’ activities and products \n- Software engineering training |\n| 2 Center and Intra-Center Elements (Directorates, Divisions) | - Software quality assurance plan (to include SQA procedures), which is referenced by the software plan and is administered by a center-level software quality assurance organization that is independent of the individual projects \n- Approach for reviewing and approving projects’ software plans \n- Approach for developing and approving lower level standards, procedures, and plans |\n| 3 Branches and Software Projects | - Software engineering (management and development) standards and processes \n- Software plan \n- PAL and other related software assets \n- Project-related software training \n- Software products resulting from applying the process defined by the plan |\n\n2.3.1 Level 1: NASA Headquarters, IV&V Facility, and Software Working Group\n\nThe NASA Software Strategic Plan (Reference 3), completed in July 1995, complements the Agency-wide strategic vision and mission statements while focusing on software within NASA. This plan was developed by the NASA Software Working Group (SWG) under the auspices of the NASA Software Independent Validation and Verification (IV&V) Facility at Fairmont, West Virginia, sponsored by the Office of Safety and Mission Assurance (OSMA) at Headquarters (HQ). The goals and implementation strategies of the NASA Software Strategic Plan address (1) defining and improving software engineering processes (including processes for management, development, and quality assurance), (2) transferring software product and process technologies, and (3) maintaining a core competency in software. Those three elements comprise the NASA Software Program.\n\nThe NASA Software Working Group is the implementation vehicle for the NASA Software Program. The role of the SWG is as follows:\n\n- Define, refine, and implement the goals of the NASA Software Strategic Plan\n- Provide guidance to all NASA software-related activities\nEnsure that available software processes are disseminated\n\nThe SWG has one or two representatives from each center and is chaired by a member of the IV&V Facility.\n\nA 1993 survey of NASA Centers (Reference 1) found that NASA does not have a common set of software standards that is used across the Agency in the manner of the Department of Defense’s military standard (Reference 4). One focus of the NASA SWG is to produce guidebooks and supporting training on the basis of NASA-wide experience in key areas such as project management, assurance, risk management, and software process improvement (see Section 2.4 for examples).\n\n2.3.2 Level 2: Center and Intra-Center Elements\n\nFor the most part, individual centers have given directorates, divisions, and offices the responsibility for developing their own standards and common processes. According to the 1993 survey (Reference 1), two NASA centers (the Marshall Space Flight Center (MSFC) and the Jet Propulsion Laboratory (JPL)) have written software development standards that are baselined at the center level and include a formal waiver process. The other centers have software standards and processes implemented at a lower organizational level. Center-level activities typically focus on defining approaches for plan review and approval. For critical mission systems, however, the SQA organization at each center has the responsibility to ensure that, throughout the life cycle of the project, software engineering activities are performed and software products are prepared in accordance with the software project’s software plan.\n\n2.3.3 Level 3: Branches and Software Projects\n\nBranch managers and software project managers share responsibility for developing and approving lower level standards, procedures, and plans for implementing the software process in their areas. They are responsible for the following:\n\n- Identifying, developing, and maintaining those lower level standards, procedures, and plans that are unique to a particular development effort and those that are common to families of software products\n- Providing training for their development efforts\n- Establishing and maintaining local PALs that contain locally specific process assets\n\nLower level software engineering process functions define, develop, and implement needed software process assets that are not provided in a higher level NASA PAL. They are also responsible for defining, developing, and implementing a software process improvement program that supports the needs of the projects and branches and for providing software-related information required by higher level measurement and process improvement programs.\n\nEach project must plan its own specific approach for accomplishing the software work assigned to it. The approach must be documented in a software plan and must comply with the local and higher level process requirements.\n2.4 Process Assets\n\nThe software team uses process assets from an experience-based PAL. A PAL is a compilation of NASA estimating and planning models, historical data, life-cycle models, activity definitions, product standards and templates, and examples of good practices that are available to a software project for developing, maintaining, and implementing its defined process. A PAL may be implemented at any and all organizational levels, as appropriate, within a NASA organization responsible for systems development.\n\nAn organization’s PAL typically contains the following products:\n\n- Higher level NASA process assets\n- All of the local organization’s software process definition documents\n- Software-related guidebooks, handbooks, and white papers, as they become available\n- Recommended activity and method definitions and product standards applied within the organization\n- Training material related to the organization’s software process\n- Plans and results from software process studies\n- Other assets that the organization determines to be applicable\n\nThis *Software Management Guidebook* and other NASA headquarters-level software-related products (for example, the NASA *Software Measurement Guidebook* (Reference 5) and the NASA *Software Process Improvement Guidebook* (Reference 2)) are included in every NASA PAL. Every PAL must also include copies of NASA Management Instruction (NMI) 2410.10B and other software-related NMIs.\n\nNASA’s *Software Management Guidebook* is a primary source of guidance to the manager in preparing the project’s software plan (see Section 3.2) and selecting appropriate elements from the PAL:\n\n- Life-cycle models (for example, waterfall, iterative refinement, spiral)\n- Milestone reviews (for example, requirements reviews, design reviews)\n- Products and product formats (for example, degree of formality, packaging)\n- Engineering methods (for example, structured approach, object-oriented approach, the Cleanroom method)\n- Product V&V methods (for example, peer review methods, testing methods)\n- Product control methods (for example, degree of formality)\n\nUsing these assets, each software manager prepares a project-specific software plan that defines the selected life-cycle model, methods, tools, and product standards the software team will use. Managers may also use their organizations’ PALs (of varying degrees of formality and structure) as sources of more detailed software process assets that have been tailored for specific application domains. This common tailoring approach allows each software project to draw on proven, successful methods appropriate to satisfy their customers’ needs in a predictable, efficient, and cost-effective manner.\n3. The Software Project’s Process\n\nThis chapter summarizes the software project’s process, which includes required activities from developing a software plan that meets the unique needs of each customer through delivery of the final software product and close-out of the project. This chapter also briefly discusses the project software plan, which documents the project’s process.\n\n3.1 The Five-Step Project Process\n\nFigure 3–1 is a summary of the five key steps required to take a software engineering project from inception through final delivery and close-out. Subsequent chapters of this guidebook expand on each of the steps. Table 3–1 maps the five steps to the applicable section of this guidebook.\n\n<table>\n<thead>\n<tr>\n<th>Project Process Step</th>\n<th>Handbook Section</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>STEP 1</td>\n<td>Chapter 4: Beginning to Plan the Project: Understanding the Scope of Work</td>\n</tr>\n<tr>\n<td>STEP 2</td>\n<td>Chapter 5: Defining the Technical Approach</td>\n</tr>\n<tr>\n<td>STEP 3</td>\n<td>Chapter 6: Finishing the Software Plan—Defining the Management Approach</td>\n</tr>\n<tr>\n<td>STEP 4</td>\n<td>Section 7.1: Managing the Project</td>\n</tr>\n<tr>\n<td>STEP 5</td>\n<td>Section 7.2: Closing Out the Project</td>\n</tr>\n</tbody>\n</table>\nFigure 3-1. The Five-Step Project Process\n\nSTEP 1 BEGIN TO PLAN THE PROJECT. UNDERSTAND THE SCOPE OF THE WORK. (Chapter 4)\n- Ascertain the customer’s requirements and constraints from the software requirements specifications, discussions with the customer, etc.\n- Ascertain the customer’s goals and objectives (overall cost, schedule, and product qualities) primarily from discussions with the customer and higher levels of NASA.\n- Understand management’s “risk tolerance level” (both the project team’s management and the\n- Reach agreement with the customer regarding the products to be delivered and the goals for each product with respect to product cost, schedule, and qualities.\n- Document the customer’s requirements and constraints, goals and objectives, and management’s risk tolerance level in the project’s software plan. Document the products to be delivered in the\n\nSTEP 2 DEFINE THE TECHNICAL APPROACH THAT BEST ACHIEVES STEP 1. (Chapter 5)\n- Incorporate appropriate lessons learned from similar or related software projects.\n- Select an appropriate life-cycle model.\n- Populate the life-cycle model with appropriate technical activities, methods and techniques, and products.\n- Identify any software process improvement activities to be conducted (that is, variations from recommended approaches or required standards).\n- Review the technical process using the organization-defined review process.\n- Iterate until all stakeholders (project team and customer) are satisfied with the technical process.\n- Document the project’s technical process in the project’s software plan.\n\nSTEP 3 FINISH THE SOFTWARE PLAN. DEFINE THE MANAGEMENT APPROACH. (Chapter 6)\n- Define and document the management approach to support the technical approach developed in Step 2.\n - Establish the software project’s organizational structure.\n - Estimate and schedule the work.\n - Identify and plan for team training.\n - Identify and plan for risks.\n - Select measures to facilitate monitoring and controlling the project.\n- Review the estimates, schedule, and plan using the organization-defined review procedure.\n- Iterate among Steps 1 through 3 until all stakeholders are satisfied with the plan.\n\nSTEP 4 RUN THE PROJECT (EXECUTE THE PROJECT’S SOFTWARE PLAN). (Section 7.1)\n- Use the life-cycle milestone reviews and appropriate training to help ensure that project personnel understand the products, activities and methods, responsibilities, etc. at each new life-cycle phase.\n- Monitor and control the project based on the software plan.\n- Review project status periodically with higher levels of management, the customer, and the software team.\n- Review the software plan regularly (for example, in conjunction with significant changes, deviations from the software plan, milestone events) and update as needed and as appropriate.\n- Maintain necessary project records.\n\nSTEP 5 CLOSE OUT THE PROJECT. (Section 7.2)\n- Complete the software project history.\n- Submit project close-out data.\n- Communicate lessons learned to other parts of the organization.\n3.2 Documenting the Project’s Process—The Software Plan\n\nActivity Requirements\n\nPlanning the Software Project\n\nObjective. Develop a comprehensive plan, based on best practices proven on NASA projects, that will guide the software team through the entire software engineering effort.\n\nKey elements, roles, and responsibilities. The software manager develops and records the software plan for conducting the activities required by this guidebook and by other software-related requirements. Three sets of significant activities (the first three steps of the five-step project process) need to be performed to plan a software project (shaded area on Figure 3–2):\n\n1. Understand the scope of the work (Chapter 4)\n2. Define the optimal technical approach (Chapter 5)\n3. Define the corresponding management approach (Chapter 6)\n\n(The next three sections of the guidebook provide details on each of these three important sets of activities.)\n\nThe independent SQA representative prepares the software quality assurance portion of the software plan and the project’s software configuration manager prepares the software configuration management portion of the software plan. This planning is consistent with system-level planning. Software plans are reviewed and approved in accordance with organization-defined procedures, as are significant changes to previously approved plans.\n\nThe development and recording of planning and engineering information are intrinsic parts of the software process and are to be performed regardless of whether the information is required as part of the deliverables. The organization’s software plan documentation standard serves as a checklist of items to be covered in the planning or engineering activity. To enhance the usability of the information, portions of the plan may be bound or maintained separately. Examples include separate documents for SQA and SCM plans.\n\nPrimary products. The primary product from this activity is as follows:\n\n- Project software plan\nEvery software project has its own software process. The project’s software plan documents the process and provides a disciplined approach to organizing and managing a software project. The existence of a plan does not guarantee project success; the key to successful software management is generating and maintaining a realistic, usable plan and then following it. Following the plan involves not only maintaining the plan itself, but also performing activities to measure progress and performance against the plan. Use the plan to assist in recognizing danger signals, and take early and appropriate actions to solve problems.\n\nThis guidebook does not mandate a specific format for a software plan; however, every PAL should include good examples of software management plans and a reusable template for such a plan. An excellent example of such a template is the *Reusable Software Management Plan* developed by the Software Assurance Technology Center at the Goddard Space Flight Center (GSFC) (Reference 6). It includes an on-line help tool for tailoring the text to an individual software project. Another excellent example is provided in the NASA Software Engineering Laboratory’s *Manager’s Handbook for Software Development* (Reference 7). Depending on the specific development environment, items may be arranged differently or new material may be added. In nearly all cases, a project’s software plan will be contained in more than one physical document, because many of the plan’s components will be common to multiple projects (for example, a QA or CM plan). However, the project’s software plan must contain references to all required topics that are packaged separately.\n\nBy completing the initial plan early in the life cycle, the manager becomes familiar with the essential aspects of the specific software engineering effort:\n\n- Scope and requirements of the project\n- Overall schedule and milestones\n- Staff requirements\n\n*Figure 3–2. Planning the Software Project*\nEach manager defines the project’s technical approach, driven by the customer’s requirements, constraints, goals, and objectives; management’s risk tolerance level; and the target and development or maintenance environments. The technical approach is described in the software plan and should concentrate on information unique to, or tailored for, a specific project. Simply reference applicable documents that contain standard policies, guidelines, standards, and procedures to be applied; do not restate that information in detail. Begin to write the plan as soon as information about the project’s definition and scope is available. The plan should be available within the first 30 to 60 days of the project, except for information that will not be available until later in the life cycle (indicate who will supply any missing information and when it will be provided). Distribute copies of the plan to all levels of project management, to the client, and to the software team.\n\nThe following additional points are included here for completeness and to ensure common understanding. While developing the plan and running the project:\n\n- Incorporate lessons learned from other similar or related software projects. Read software project history reports from those projects.\n- Use sound judgment. One significant lesson learned from performing software engineering on NASA projects is that no single life-cycle model, analysis and design method, testing method, degree of formality of documents and reviews, etc. is appropriate for every NASA software project. Use of sound, professional judgment is expected with respect to decisions related to such topics.\n- You can always do more. This guidebook defines the minimum required software activities and products, not the precise set of things to do. If a manager or project team feels that something additional would be useful, they are empowered to do so.\n- Remember that you are not alone in this planning effort; you are not the first nor will you be the last to plan a new or different software project. Consult with other software managers for their opinions, advice, and ideas.\n\nFigure 3–3 illustrates the inputs to the process of preparing a tailored software plan:\n\n- The customer’s requirements and constraints as well as his or her goals and objectives\n- The risk tolerance levels of the project manager and of the project’s organizational management\n- Reusable process assets from local and higher level PALs\n- The NASA Software Management Guidebook (this document)\n- The NASA Software Measurement Guidebook (Reference 5)\n- The NASA Software Process Improvement Guidebook (Reference 2)\nSoftware Measurement Guidebook presents information on the purpose and importance of measurement for\n1. Understanding and modeling the software engineering process\n2. Aiding in the management of software projects\n3. Guiding improvement in software engineering processes\n\nIt discusses the specific procedures and activities of an organizational measurement program and the roles of the people involved. The guidebook also clarifies the role that measurement can and must play in the goal of continual, sustained improvement for all software production and maintenance efforts.\n\nThe Software Process Improvement Guidebook is a companion document that describes how a software project uses a new technology (that is, one that has not yet been proven anywhere within the organization) in a controlled fashion and quantitatively assesses the effect of the technology on the products generated and the process used.\n4. Beginning to Plan the Project: Understanding the Scope of Work\n\nThis chapter describes activities that are required to begin planning the project. Software project planning need not wait, indeed must not wait, for receipt of the final software requirements to begin the project planning process. It should begin as soon as project personnel become aware of the intent of the customer to initiate a new software effort, and it should be coordinated, as much as possible, with other NASA groups responsible for related requirements.\n\n**Activity Requirements**\n\n**Understanding the Scope of Work**\n\n**Objective.** Record the project’s understanding of the scope of the work to be performed. This activity forms the basis for the technical and management approaches.\n\n**Key elements, roles, and responsibilities.** The software manager records, in the software plan, his or her understanding of the following:\n\n- The customer’s requirements, constraints, and contributions\n- The customer’s goals and objectives\n- Management’s risk tolerance level\n- Products to be delivered to the customer and their characteristics\n\n**Primary products.** The primary product from this activity is as follows:\n\n- Required portions of the project’s software plan\n\nThe rest of this chapter provides guidance in accomplishing this required activity.\n\n4.1 Ascertaining Customer Requirements and Constraints\n\nAscertain the customer’s requirements and constraints from the software requirements specifications, discussions with the customer, and any other appropriate means. The customer may have only a general idea of the software requirements; determination of detailed requirements may follow later or may even be part of the project. (The same applies to characteristics of products to be delivered.)\n\nNASA experience has been that the more the end user of the software product is involved throughout the product’s engineering life cycle, the more likely the expected product will result. The customer, however, is not always the end user of the software product. When this is the case, work with the customer to encourage that the end user be as involved throughout as much of the product’s life cycle as possible. This involvement is particularly crucial during the requirements analysis and design activities early in the life cycle. It is also important to try to get end-user involvement at milestone reviews.\n4.2 Ascertaining Customer Goals and Objectives\n\nDuring meetings with the customer, ascertain the customer’s organizational goals and specific project objectives regarding overall cost, schedule, and product qualities. Also understand the goals of higher levels of the organization. The software manager and customer use the goals to determine and agree on the appropriate robustness desired of product, formality and level of detail and polish in documents, milestone review presentations, and so on. The software manager defines, in the project’s software plan, the specific approach that best addresses the application domain, the objectives established for the project, and the size of the effort. Table 4–1 provides examples of the types of objectives that might be established for a project.\n\n<table>\n<thead>\n<tr>\n<th>Objective</th>\n<th>Examples</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Cost</td>\n<td>• Minimize cost to develop<br>• Minimize cost to maintain</td>\n</tr>\n<tr>\n<td>Schedule</td>\n<td>• Deliver by fixed date (for example, 90 days before launch)</td>\n</tr>\n<tr>\n<td>Product Qualities</td>\n<td>• Maximize reusability<br>• Maximize robustness<br>• Maximize freedom from defects<br>• Maximize performance (for example, response time)<br>• Maximize maintainability or extensibility</td>\n</tr>\n</tbody>\n</table>\n4.3 Understanding Management’s Risk Tolerance\n\nTo minimize costs or cycle time, it is sometimes necessary to introduce risk. Understand what level of risk tolerance is acceptable to the management of both the development or maintenance organization and the customer’s organization, and include a risk management approach in the software plan that accommodates that level of risk. (See Section 6.3.)\n\nAn approach for continuous risk management is explained in detail in the Software Engineering Institute’s (SEI’s) technical report *Continuous Risk Management Guidebook* (Reference 8), recently adopted by the NASA Software Program for use throughout the Agency.\n\n4.4 Understanding Products to be Delivered and Their Characteristics\n\nReach agreement with the customer regarding the products to be delivered and the goals for each product with respect to its cost, schedule, and qualities. Remember that initially the customer may have only a general idea of the product requirements; determination of specific products may follow later or may even be part of the project.\n\n4.4.1 Documentation\n\nThe amount of time and effort expended in producing a document can vary considerably. (Refer to the glossary for the definition of *documentation.*) Factors that affect document production include the following:\n\n- Audience for the document—points of view and levels of experience of the readers\n- General format\n- Level of detail\n- Degree of formality\n\nFor deliverable documents, the following additional factors apply:\n\n- Paper vs. electronic delivery (if paper, the number of copies per delivery)\n- Number of interim deliverable versions\n\nTIPS\n\n- To retain control, avoid using the staff of a technical publications department on early drafts of documents and on documents that will not be delivered to the customer.\n- Give outlines or early drafts to the customer for review.\n\n4.4.2 Software Product Releases\n\nUse interim software releases (as opposed to the “big bang” approach) either to satisfy early operational needs of the customer or as a risk mitigation technique (for example, to ensure the feasibility of high-risk requirements). Integrating and testing the system in parts helps to localize\nerrors and reduce debugging time. Early releases also help to build the customer’s confidence level, as well as that of management, that the project is on track.\n\n4.4.3 Milestone Reviews\n\nMilestone reviews and associated review material should also be treated as deliverable products. That is, discuss their goals with the customer in terms of responsibilities, cost, schedule, and qualities. Many of the factors that affect producing documentation-oriented products also apply to milestone reviews. (See Section 5.2.9 for details.)\n5. Defining the Technical Approach\n\nChapter 4 described the first step in the planning process: understanding the scope of the work to be performed. The next step is to define a technical approach that best accomplishes the work, which is the subject of this chapter. It includes selecting an appropriate life-cycle model along with corresponding activities, methods, and products.\n\n### Activity Requirements\n\n**Objective.** Document the technical approach that the software team will use to accomplish the software work identified in Chapter 4.\n\n**Key elements, roles, and responsibilities.** The software manager defines the project’s technical approach by selecting an appropriate life-cycle model and methods for performing required activities, and appropriate packaging techniques for required products. To facilitate developing each project’s technical approach and to avoid reinventing the wheel, this guidebook contains a summary of effective, proven, recommended life-cycle models and methods from which the software manager can choose to satisfy the required common activities.\n\nIf, however, the manager believes that a different, unproven method would be more appropriate, then he or she is encouraged to try it out in a controlled fashion by planning a process study (see Section 2.2.3). Such a study allows the manager to capture data about the use of the alternative approach and to measure its overall effect on the software product and process.\n\nIf the software manager feels that additional activities or products would be useful, he or she is expected to apply sound, professional judgment in decisions related to such topics.\n\nEach project’s tailored process is defined in its project-specific software plan.\n\n**Primary products.** The primary product from this activity is as follows:\n\n- Technical approach portions of the project’s software plan\n\nAlthough the following descriptions of process requirements and tailoring guidelines are extensive, a new project manager should not feel overly intimidated by the length of this chapter. If your new project is similar to one that another project manager has managed previously, then visit your PAL or seek out that manager and reuse the appropriate tailoring from the earlier project. Complete the applicable additional process tailoring and you will be ready to estimate and plan your project based on the specifics of your process. After you have defined the technical approach for your project, everything you need to know to complete the management approach and then run the project is provided in the following two chapters, which are much shorter.\n\n---\n\n2 “Proven” means used successfully within NASA.\n5.1 Selecting an Appropriate Life-Cycle Model\n\nThis section identifies the life-cycle models recommended for use on NASA software projects. A life-cycle model comprises one or more phases (for example, a requirements definition phase, a design phase, a test phase). Each phase is defined as the time interval between two scheduled events. For example, in the waterfall life-cycle model, the design phase is defined as the period between the software specification review and the critical design review (CDR).\n\nWithin each phase, one or more activities are executed. For example, during the waterfall model’s design phase, the design activity is performed; the test planning activity for qualification testing may be done at the same time. In most cases, activities neither begin nor end precisely at the phase boundaries; rather, they overlap adjacent phases, as illustrated in Figure 5–1.\n\nVarious methods (or techniques) may be used in the performance of an activity. For example, object-oriented design is one proven design method; structured design is another.\n\nThis document does not mandate any particular software life-cycle model, and the order of activities described here is not intended to conform to any particular model. Few specific methods are mandated for required activities. These decisions are left to the software manager, who selects an appropriate life-cycle model and activity-related methods and defines them in the\n\nFigure 5–1. Phases and Activities\nproject’s software plan. This chapter contains guidance on selecting an appropriate, recommended life-cycle model and methods for many activities.\n\nFor convenience, Table 5–1 provides the definitions (see the Glossary) of several important terms used extensively in this section.\n\n**Table 5–1. Defining a Life Cycle**\n\n<table>\n<thead>\n<tr>\n<th>Term</th>\n<th>Definition</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Software life cycle</strong></td>\n<td>“The period of time that begins when a software product is conceived and ends when the software is no longer available for use” (Reference 9). A life cycle is typically divided into life-cycle phases.</td>\n</tr>\n<tr>\n<td><strong>Life-cycle model</strong></td>\n<td>A framework on which to map activities, methods, standards, procedures, tools, products, and services (for example, waterfall, spiral).</td>\n</tr>\n<tr>\n<td><strong>Life-cycle phase</strong></td>\n<td>A division of the software effort into non-overlapping time periods. Life-cycle phases are important reference points for the software manager. Multiple activities may be performed in a life-cycle phase; an activity may span multiple phases.</td>\n</tr>\n<tr>\n<td><strong>Activity</strong></td>\n<td>A unit of work that has well-defined entry and exit criteria. Activities can usually be broken into discrete steps.</td>\n</tr>\n<tr>\n<td><strong>Method</strong></td>\n<td>A technique or approach, possibly supported by procedures and standards, that establishes a way of performing activities and arriving at a desired result.</td>\n</tr>\n</tbody>\n</table>\n\nFive life-cycle models are summarized in the following subsections. These models are recommended on the basis of NASA’s experience applying them successfully at various centers. Development is addressed before maintenance, and the development life-cycle models are ordered from the simplest and most familiar to what may be the most complex and least familiar.\n\n- Waterfall development life-cycle model\n- Incremental development life-cycle model\n- Evolutionary development life-cycle model\n- Package-based development life-cycle model\n- Legacy system maintenance life-cycle model\n5.1.1 Waterfall Development Life-Cycle Model\n\nTable 5–2 summarizes the life cycle defined by the waterfall development model.\n\nTable 5–2. Summary of Waterfall Development Life-Cycle Model\n\n| Summary description and discussion | The waterfall (single-build) life-cycle model is essentially a once-through-do-each-step-once approach. Simplistically, determine user needs, define requirements, design the system, implement the system, test, fix, and deliver the system (Reference 10). This model is illustrated in Figure 5–2. Major products and milestone reviews for this life-cycle model are summarized in Table 5–3. |\n| Advantages | • Well-studied, well-understood, and well-defined \n• Easy to model and understand \n• Easy to plan and monitor \n• Many management tools exist to support this life-cycle model |\n| Disadvantages | • Most if not all requirements must be known up front \n• Does not readily accommodate requirements changes \n• Product is not available for initial use until the project is nearly done |\n| Most appropriate when ... | • Project is similar to one done successfully before \n• Requirements are quite stable and well-understood \n• The design and technology are proven and mature \n• Total project duration is relatively short (less than a year) \n• Customer does not need any interim releases |\nFigure 5-2. Waterfall Development Life-Cycle Model\n\nTable 5-3. Products and Milestone Reviews for the Waterfall Development Life-Cycle Model\n\n<table>\n<thead>\n<tr>\n<th>Life-cycle phase</th>\n<th>Major products</th>\n<th>Milestone reviews</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Project planning</td>\n<td>• Software plan</td>\n<td>None</td>\n</tr>\n<tr>\n<td>Requirements definition and analysis</td>\n<td>• Software requirements specification (SWRS)</td>\n<td>Software Specification Review (SSR)</td>\n</tr>\n<tr>\n<td>Architectural design</td>\n<td>• Software design specification (SWDS), preliminary</td>\n<td>Preliminary Design Review (PDR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Qualification test plan</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Preliminary user’s guide</td>\n<td></td>\n</tr>\n<tr>\n<td>Detailed design</td>\n<td>• Software design specification (SWDS), detailed</td>\n<td>Critical Design Review (CDR)</td>\n</tr>\n<tr>\n<td>Implementation and testing</td>\n<td>• Unit-level design</td>\n<td>Qualification Test Readiness Review (QTRR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Implemented, tested software</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Qualification test procedures</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Draft user’s guide</td>\n<td></td>\n</tr>\n<tr>\n<td>Qualification testing</td>\n<td>• Qualification-tested software</td>\n<td>Acceptance Test Readiness Review (ATRR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Qualification test report</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Final user’s guide</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• As-built software description</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n5.1.2 Incremental Development Life-Cycle Model\n\nTable 5–4 summarizes the life cycle defined by the incremental development model.\n\n**Table 5–4. Summary of Incremental Development Life-Cycle Model**\n\n| Summary description and discussion | The incremental (multi-build) life-cycle model determines user needs and defines a subset of the system requirements, then performs the rest of the development in a sequence of builds. The first build incorporates part of the planned capabilities, the next build adds more capabilities, and so on, until the system is complete (Reference 10). This model is illustrated in Figure 5–3. Major products and milestone reviews for this life-cycle model are summarized in Table 5–5. |\n| Advantages | • Reduces risks of schedule slips, requirements changes, and acceptance problems \n• Increases manageability \n• Interim builds of the product facilitate feeding back changes in subsequent builds \n• Interim builds may be delivered before the final version is done; this allows end users to identify needed changes \n• Breaks up development for long lead time projects \n• Allows users to validate the product as it is developed \n• Allows software team to defer development of less well understood requirements to later releases after issues have been resolved \n• Allows for early operational training on interim versions of the product \n• Allows for validation of operational procedures early \n• Includes well-defined checkpoints with customer and users via reviews |\n| Disadvantages | • Like the waterfall life-cycle model, most if not all requirements must be known up front \n• Sensitive to how specific builds are selected \n• Places products (particularly requirements) under configuration control early in the life cycle, thereby requiring formal change control procedures that may increase overhead, particularly if requirements are unstable |\n| Most appropriate when ... | • Project is similar to one done successfully before \n• Most of the requirements are stable and well-understood; but some TBDs may exist \n• The design and technology are proven and mature \n• Total project duration is greater than one year or customer needs interim release(s) |\nFigure 5-3. Incremental Development Life-Cycle Model\n\nTable 5-5. Products and Milestone Reviews for the Incremental Development Life-Cycle Model\n\n<table>\n<thead>\n<tr>\n<th>Life-cycle phase</th>\n<th>Major products</th>\n<th>Milestone reviews</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Project planning</td>\n<td>• Software plan</td>\n<td>None</td>\n</tr>\n<tr>\n<td>Requirements definition</td>\n<td>• Software requirements specification (SWRS)</td>\n<td>Software Specification Review (SSR)</td>\n</tr>\n<tr>\n<td>and analysis</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td>Architectural design</td>\n<td>• Software design specification (SWDS), preliminary</td>\n<td>Preliminary Design Review (PDR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Qualification test plan</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Preliminary user’s guide</td>\n<td></td>\n</tr>\n<tr>\n<td>Detailed design</td>\n<td>• Software design specification (SWDS), detailed through at least the first build</td>\n<td>Critical Design Review (CDR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Software design specification (SWDS), detailed through at least the next build</td>\n<td>Build Design Review (BDR)</td>\n</tr>\n<tr>\n<td>Implementation and testing</td>\n<td>• Unit-level design</td>\n<td>Qualification Test Readiness Review (QTRR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Implemented, tested software</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Qualification test procedures</td>\n<td></td>\n</tr>\n<tr>\n<td>Qualification testing</td>\n<td>• Qualification-tested software</td>\n<td>Acceptance Test Readiness Review (ATRR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Qualification test report</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Final user’s guide</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• As-built software description</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n5.1.3 Evolutionary Development Life-Cycle Model\n\nTable 5–6 summarizes the life cycle defined by the evolutionary development model.\n\n<table>\n<thead>\n<tr>\n<th>Summary description and discussion</th>\n<th>Like the incremental development model, the evolutionary life-cycle model also develops a system in builds, but differs from the incremental model in acknowledging that the user needs are not fully understood and not all requirements can be defined up front. In the evolutionary approach, user needs and system requirements are partially defined up front, then are refined in each succeeding build. The system evolves as the understanding of user needs and the resolution of issues occurs. Prototyping is especially useful in this life-cycle model. (The evolutionary development life-cycle model is sometimes referred to as a spiral development model, but it is not the same as Boehm’s spiral model (Reference 11). This model is also sometimes referred to as a prototyping life-cycle model, but it should not be confused with the prototyping technique defined in Section 5.2.1.) This life-cycle model is illustrated in Figure 5–4. Major products and milestone reviews for this model are summarized in Table 5–7.</th>\n</tr>\n</thead>\n</table>\n| Advantages | • Not all requirements need be known up front \n• Addressing high risk issues (for example, new technologies or unclear requirements) early may reduce risk \n• Like the incremental life-cycle model, interim builds of the product facilitate feeding back changes in subsequent builds \n• Users are actively involved in definition and evaluation of the system \n• Prototyping techniques enable developers to demonstrate functionality to users with minimal of effort \n• Even if time or money runs out, some amount of operational capability is available |\n| Disadvantages | • Because not all requirements are well-understood up front, the total effort involved in the project is difficult to estimate early. Therefore, expect accurate estimates only for the next cycle, not for the entire development effort. \n• Less experience on how to manage (progress is difficult to measure) \n• Risk of never-ending evolution (for example, continual “gold plating”) \n• May be difficult to manage when cost ceilings or fixed delivery dates are specified \n• Will not be successful without user involvement |\n| Most appropriate when ... | • Requirements or design are not well-defined, not well-understood, or likely to undergo significant changes \n• New or unproved technologies are being introduced \n• System capabilities can be demonstrated for evaluation by users \n• There are diverse user groups with potentially conflicting needs |\nTable 5-7. Products and Milestone Reviews for the Evolutionary Development Life-Cycle Model\n\n<table>\n<thead>\n<tr>\n<th>Life-cycle phase</th>\n<th>Major products</th>\n<th>Milestone reviews</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Concept definition</td>\n<td>• Initial System Development Plan to be updated in later phases</td>\n<td>System Concept Review (SCR)</td>\n</tr>\n<tr>\n<td>Requirements and architecture</td>\n<td>• Preliminary requirements document</td>\n<td>Combined System Requirements Review (SRR) and System</td>\n</tr>\n<tr>\n<td>definition</td>\n<td>• Architectural design document containing the infrastructure plus the</td>\n<td>Design Review (SDR)</td>\n</tr>\n<tr>\n<td></td>\n<td>architecture of each release as it evolves</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Requirements traceability map</td>\n<td></td>\n</tr>\n<tr>\n<td>Implementation</td>\n<td>• Evolutionary Implementation Plan</td>\n<td>Timebox assessments</td>\n</tr>\n<tr>\n<td></td>\n<td>• Timebox plan for each timebox (see Table 6-3)</td>\n<td>Qualification testing after all timeboxes for the</td>\n</tr>\n<tr>\n<td></td>\n<td>• Software product baseline combining new, reused, and off-the-shelf products</td>\n<td>release have been completed</td>\n</tr>\n<tr>\n<td></td>\n<td>• Updated requirements traceability map</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Draft user documentation</td>\n<td></td>\n</tr>\n<tr>\n<td>Integration and test</td>\n<td>• System test procedures</td>\n<td>Acceptance Test Readiness Review (ATRR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Integrated, tested software</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Qualification test report</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Final user documentation</td>\n<td></td>\n</tr>\n<tr>\n<td>Installation and acceptance</td>\n<td>(Although these system life-cycle phases are shown in Figure 5–4 for</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>completeness, they are not discussed here, or in the corresponding tables</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>for the other life-cycle models, because they are out of the scope of the</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>software life cycle.</td>\n<td></td>\n</tr>\n<tr>\n<td>Operations and maintenance</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n5.1.4 Package-Based Development Life-Cycle Model\n\nTable 5–8 summarizes the life cycle defined by the package-based development model.\n\nTable 5–8. Summary of Package-Based Development Life-Cycle Model\n\n| Summary description and discussion | The package-based development life-cycle model is used for system development based largely on the use of commercial-off-the-shelf and Government off-the-shelf products and reusable packages (Reference 12). Typically, some custom software development is needed to provide interfaces among the NDIs. This model is illustrated in Figure 5–5. Major products and milestone reviews for this life-cycle model are summarized in Table 5–9. |\n| Advantages | • Lower cost than developing equivalent functionality from scratch \n• Cycle time also often lower than developing equivalent functionality from scratch \n• Improves confidence in quality of the end product (since quality of NDIs is already known) |\n| Disadvantages | • May result in compromises between desired functionality and functionality provided by NDIs \n• Maintainability may be more of a challenge because source of NDIs may not be the same NASA organization (for example, requires third party to make changes, raises SCM issues when NDI vendor releases updated versions) |\n| Most appropriate when ... | • A significant portion of the functionality of a system can be provided by NDIs |\nFigure 5-5. Package-Based Development Life-Cycle Model\n\nTable 5-9. Major Products and Milestone Reviews for the Package-Based Development Life-Cycle Model\n\n<table>\n<thead>\n<tr>\n<th>Life-cycle phase</th>\n<th>Major products</th>\n<th>Milestone reviews</th>\n</tr>\n</thead>\n</table>\n| Requirements Analysis and Package Identification | • System Development Plan \n• Requirements \n• Strawman high-level architecture \n• Candidate packages | System Requirements Review (SRR) |\n| Architectural Definition and Package Selection | • Modified requirements \n• System architecture \n• Final packages | System Design Review (SDR) |\n| System Integration and Test | • Delivered system | User demonstrations \nOperational Readiness Review (ORR) |\n| Technology Update and System Maintenance | • Enhanced system | User demonstrations |\n5.1.5 Legacy System Maintenance Life-Cycle Model\n\nTable 5–10 summarizes the life cycle defined by the legacy system maintenance model.\n\nTable 5–10. Summary of Legacy System Maintenance Life-Cycle Model\n\n<table>\n<thead>\n<tr>\n<th>Summary description and discussion</th>\n<th>Most appropriate when ...</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>The legacy system maintenance release life-cycle model is used to apply fixes or minor enhancements to an operational system. (Use a waterfall or incremental life-cycle model for major enhancements.) Selected and sometimes abbreviated activities performed in the software development life cycles are also performed during maintenance. The legacy system maintenance life-cycle model is similar in nature to the waterfall life-cycle model; the primary difference is that the architectural design has already been established (Reference 10). This model is illustrated in Figure 5–6. Major products and milestone reviews for this life-cycle model are summarized in Table 5–11. Maintenance release comprises only fixes and minor enhancements.</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nFigure 5–6. Legacy System Maintenance Life-Cycle Model\nTable 5-11. Products and Milestone Reviews for the Legacy System Maintenance Life-Cycle Model\n\n<table>\n<thead>\n<tr>\n<th>Life-cycle phase</th>\n<th>Major products</th>\n<th>Milestone reviews</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Release planning</td>\n<td>• Release contents agreement</td>\n<td>Release Contents Review (RCR)</td>\n</tr>\n<tr>\n<td>Requirements definition and analysis</td>\n<td>• Release requirements specification</td>\n<td>Release Requirements Review (RRR)</td>\n</tr>\n<tr>\n<td>Design</td>\n<td>• Release design specification</td>\n<td>Release Design Review (RDR)</td>\n</tr>\n<tr>\n<td>Implementation and testing</td>\n<td>• Unit-level design</td>\n<td>Release Qualification Test Readiness Review (RQTRR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Implemented, tested software</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Qualification test plan and procedures</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Draft user's guide updates</td>\n<td></td>\n</tr>\n<tr>\n<td>Qualification testing</td>\n<td>• Qualification-tested software</td>\n<td>Acceptance Test Readiness Review (ATRR)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Qualification test report</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• Final user's guide updates</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>• As-built software description updates</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n5.2 Selecting Appropriate Activities, Methods, and Products\n\nAfter an appropriate life-cycle model has been selected, it must be populated with software engineering activities, methods, techniques, and products that will help achieve the goals and objectives established for the project. The following subsections present implementation guidance for each required activity (see Table 2–1) and identify recommended methods for performing those activities.\n\nTwo logical groups of activities are described in this section:\n\n1. Activities that are performed to produce a specific software product (shaded in Figure 5–7, Primary Software Engineering Activities)\n - Software CI requirements definition and analysis (Section 5.2.1)\n - Software CI design (Section 5.2.2)\n - Software CI implementation and testing (Section 5.2.3)\n - Software CI qualification testing (Section 5.2.4)\n - Preparation for software delivery (Section 5.2.5)\n\n2. Activities that are performed in support of each of the first group of activities (shaded in Figure 5–8, Software Engineering Support Activities and described beginning in Section 5.2.6)\n - Software product validation and verification (Section 5.2.6)\n - Software configuration management (Section 5.2.7)\n - Software quality assurance (Section 5.2.8)\n - Milestone reviews (Section 5.2.9)\nMonitor and control software project\n(maintain project software plan\nand records as necessary)\n\nPrepare software team\n\nIndependently assure software products and activities (SQA)\n\nManage configuration (SCM)\n\nParticipate in milestone reviews\n\nValidate and verify (V&V) software products\n\nPerform required technical activities\n(i.e., software CI requirements definition and\nanalysis through qualification testing,\nincluding interim deliveries)\nuntil final product is delivered\n\nDeliver final software products\n\nFigure 5-7. Primary Software Engineering Activities\n\nFigure 5-8. Software Engineering Support Activities\n5.2.1 Software CI Requirements Definition and Analysis\n\nActivity Requirements\n\nSoftware CI Requirement Definition and Analysis\n\nObjective. Software requirements form the foundation for all subsequent design and implementation activities. They also form the basis for the customer’s acceptance criteria. The quality of the software requirements directly affects the success of the project; therefore, the objective of this activity is to ensure that high-quality software requirements specifications are made available to the software designers, implementers, and testers.\n\nKey elements, roles, and responsibilities.\n\n- When no requirements are provided to the software team, software requirements analysts (sometimes referred to as system engineers) elicit them from the customer, end users, and others as appropriate.\n- When higher level requirements are provided (for example, system-level requirements), the analysts examine the requirements for completeness, consistency, and understandability, then derive the software requirements from them.\n- When detailed requirements for the software are provided, the analysts examine those requirements for completeness, consistency, and understandability.\n- The software requirements analysts record the software requirements to be met by each software CI, the methods to be used to ensure that each requirement has been met, and the traceability between the software CI requirements and higher level requirements (if any). The resulting document includes all applicable items in the software CI requirements specification (SWRS) documentation standard.\n- Conduct the following support activities in conjunction with this activity:\n - Validate and verify products of this activity, intermediate and final, in accordance with Section 5.2.6\n - Finalize the products of this activity by holding milestone reviews in accordance with Section 5.2.9\n - Control products of this activity in accordance with Section 5.2.7\n\nPrimary products. The primary products from this activity are as follows:\n\n- Software CI requirements specification\n- Product V&V records for requirements definition and analysis products\n- Milestone review of software requirements\n\nRecommended methods\n\n- Structured requirements analysis (Table 5–12)\n- Object-oriented requirements analysis (Table 5–13)\n### Table 5-12. Structured Requirements Analysis Method\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Structured requirements analysis is a method of analyzing and specifying the requirements of a product from a functional point of view. Structured analysis includes the use of data flow diagrams, data dictionaries, structured English, decision tables, and decision trees to develop a structured requirements specification.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>Familiar to most software requirements analysts</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td>It is sometimes difficult to transform data flow diagrams from this activity into structure charts in the Software CI Design activity</td>\n</tr>\n<tr>\n<td><strong>Most appropriate when ...</strong></td>\n<td>- Structured techniques will be used throughout the effort</td>\n</tr>\n<tr>\n<td></td>\n<td>- The problem to be solved is well-understood</td>\n</tr>\n<tr>\n<td>Key products</td>\n<td>Software requirements specification (SWRS), including the following:</td>\n</tr>\n<tr>\n<td></td>\n<td>- Classification of requirements by clarity level (fully defined, needs clarification, or ambiguous) and by category (functional, performance, operations, or programmatic)</td>\n</tr>\n<tr>\n<td></td>\n<td>- Data flow diagrams (DFDs)</td>\n</tr>\n<tr>\n<td></td>\n<td>- Function specifications</td>\n</tr>\n<tr>\n<td></td>\n<td>- Data dictionaries</td>\n</tr>\n<tr>\n<td></td>\n<td>- Identification and definition of external interfaces</td>\n</tr>\n<tr>\n<td></td>\n<td>- Traceability matrices (maps software requirements to higher level system requirements, if applicable)</td>\n</tr>\n</tbody>\n</table>\n**Table 5-13. Object-Oriented Requirements Analysis Method**\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Object-oriented requirements analysis is a method of analyzing and specifying the requirements of a product in terms of the objects that the system is modeling and operations that pertain to those objects.</th>\n</tr>\n</thead>\n</table>\n| **Advantages** | • There is empirical evidence within NASA that use of object-oriented technology facilitates reuse \n | • Felt by some NASA practitioners to be a more natural, intuitive approach than traditional structured approaches, resulting in products that are more maintainable and modifiable |\n| **Disadvantages** | • Can be difficult for personnel with a structured analysis background \n | • Unless a recognized object-oriented method is chosen (for example, Booch, OMT), computer-aided software engineering (CASE) tool support is limited or nonexistent |\n| **Most appropriate when ...** | • Object-oriented techniques will be used throughout the effort \n | • Reusability, maintainability, or modifiability of the products developed is an important objective \n | (The consensus of NASA personnel who have applied object-oriented methods is that object-oriented technology is applicable in most situations.) |\n| **Key products** | Software requirements specification (SWRS), including the following: \n | • Classification of requirements by clarity level (fully defined, needs clarification, or ambiguous) and by category (functional, performance, operations, or programmatic) \n | • Entity relationship diagrams, data flow diagrams, and state transition diagrams \n | • Identification and definition of external interfaces \n | • Traceability matrices (maps software requirements to higher level system requirements, if any) |\n\n**Recommended techniques**\n\n- Prototyping (Table 5-14)\n- Joint application development (JAD) workshops (Table 5-15)\nTable 5-14. Prototyping Technique\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>A prototype is an early experimental model of a system, system component, or system function that contains enough capabilities for it to be used to establish or refine requirements, or to validate critical design concepts. A prototype is not an early operational version of a system. It does not contain all required system support functions; is not meant to be as reliable or robust as an operational system; and is seldom constrained by stringent performance, safety, security, or operational requirements.</th>\n</tr>\n</thead>\n</table>\n| Advantages | • Prototyping is useful to clarify unclear requirements, to obtain buy-in on user interface characteristics, to gain experience when a new technology is being applied, or to evaluate alternative designs when major performance or reliability issues are unresolved. \n• Users get to see early versions of product functionality and provide feedback without a lot of time and effort on the part of the developers and testers. |\n| Disadvantages | • Prototyping is sometimes inappropriately used in an attempt to avoid performing proven software engineering activities like peer reviews, testing, configuration management, and documentation. \n• Users may interpret a prototype to be a finished product and not recognize (or accept) that additional work is required to develop an operational product. \n• Prototypes, even when used appropriately, have a tendency to become operational products. |\n| Most appropriate when ... | • Requirements are unclear, when the user interface is crucial, when a new technology is being applied, or when major performance or reliability issues are unresolved. |\n| Key products | • Prototype development plan \n• A prototype of the product to be developed \n• Prototype summary report |\n### Table 5-15. JAD Workshop Technique\n\n| Summary Description and Discussion | JAD is a facilitated workshop technique designed to bring together principal stakeholders to solve a well-defined problem (for example, producing a product of one of the recommended requirements analysis methods) in order to produce a well-defined product or set of products (for example, a traceability matrix). |\n| Advantages | • Includes people with authority to make decisions \n• Increases visibility into needs of customer and users, and concerns of developers \n• Facilitates discussing alternatives, and advantages and disadvantages of each \n• Reduces risk that decisions made by workshop participants will be changed later, thus reducing costs and cycle time due to less rework \n• Relies on effective group dynamics, resulting in increased synergism among stakeholders |\n| Disadvantages | Impossible if principal stakeholders are not available, not given the authority, or not backed by their management |\n| Most appropriate when ... | • Cycle time must be shortened \n• There are a number of interfacing organizations that are all stakeholders \n• Participants with knowledge and authority are available (or will be made available) \n• There is adequate time for preparation, execution, and follow up \n• An experienced facilitator and appropriate facilities are available |\n| Key products | • Workshop notes \n• Action item lists \n• Intended end products of JAD workshop (requirements specifications in this case) \n• Post-JAD management briefing |\n\n!!! **TIPS**\n\n• When the system is essentially all software, consider creating the equivalent of a *System & Operations Concept* document (including a discussion of operational scenarios) as an introduction to the software requirements specification.\n\n• Record and track to closure requirements questions and TBD requirements.\n\n• Include software qualification testers in the process of analyzing software requirements; they can review the requirements from a testability point of view.\n\n• NASA has had considerable success using team inspections (see Table 5–22 and Reference 13) for V&V of requirements products.\n5.2.2 Software CI Design\n\nActivity Requirements\n\nSoftware CI Design\n\nObjective. The objective of the software CI design activity is to translate the software CI requirements into a form that can be implemented in software.\n\nKey elements, roles, and responsibilities. This activity produces two basic levels of design: architectural or high-level design, and detailed design.\n\n- Prepare the architectural design.\n - Software design architects define and record design decisions; that is, decisions about the software CI’s behavioral design and other decisions that affect the selection and design of the software components included in the software CI. The result includes all applicable items in the software CI design section of the software CI design specification (SWDS) documentation standard.\n - Software design architects define and record the architectural design of each software CI (the software components included in the software CI, their interfaces, and a concept of execution among them) and the traceability between the software components and the software CI requirements. The result includes all applicable items in the architectural design and traceability sections of the SWDS documentation standard. Software components may consist of other software components and may be organized into as many levels as are needed to represent the software CI architecture. For example, a software CI may be divided into three software components, each of which is divided into additional software components, and so on.\n\n- Prepare the detailed design. Software detail designers develop and record a description of each lowest level software component, referred to as a unit-level component, or simply unit. The result includes all applicable items in the detailed design section of the SWDS documentation standard.\n\n- Conduct the following support activities in conjunction with this activity:\n - Validate and verify products of this activity, intermediate and final, in accordance with Software Product Validation and Verification, Section 5.2.6.\n - Finalize the products of this activity by holding milestone reviews in accordance with Milestone Reviews, Section 5.2.9.\n - Control products of this activity in accordance with Software Configuration Management, Section 5.2.7.\n\nPrimary products. The primary products from this activity are as follows:\n\n- Software CI design specification\n- Product V&V records for design products\n- Milestone review of software design\n\nRecommended methods\n\n- Structured design (Table 5–16)\n- Object-oriented design (Table 5–17)\n### Table 5-16. Structured Design Method\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Structured design is a method of designing a product from a functional point of view. Structured design includes the use of structure charts, structured English, data flow diagrams, data dictionaries, decision tables, and decision trees to develop a structured design specification.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>Familiar to most software designers</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td>There is empirical evidence within NASA that components designed using structured methods are less reusable and less maintainable than those using object-oriented methods</td>\n</tr>\n<tr>\n<td></td>\n<td>It is sometimes difficult to transform data flow diagrams from the Software CI Requirements Definition and Analysis activity into structure charts in this activity</td>\n</tr>\n<tr>\n<td>Most appropriate when ...</td>\n<td>Product being engineered is one-of-a-kind and is expected to have a relatively short life time (for example, up to a few years)</td>\n</tr>\n<tr>\n<td>Key products</td>\n<td>Software design specification (SWDS), including the following:</td>\n</tr>\n<tr>\n<td></td>\n<td>- Data flow diagrams (DFDs)</td>\n</tr>\n<tr>\n<td></td>\n<td>- Structure charts</td>\n</tr>\n<tr>\n<td></td>\n<td>- Function specifications</td>\n</tr>\n<tr>\n<td></td>\n<td>- Data dictionaries</td>\n</tr>\n<tr>\n<td></td>\n<td>- Traceability matrices (maps software design components to software requirements)</td>\n</tr>\n</tbody>\n</table>\n\n### Table 5-17. Object-Oriented Design Method\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Object-oriented design is a method of designing a product in terms of the objects that the system is modeling and operations that pertain to those objects.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>- There is empirical evidence within NASA that use of object-oriented technology facilitates reuse</td>\n</tr>\n<tr>\n<td></td>\n<td>- Felt by some NASA practitioners to be a more natural, intuitive approach than traditional structured approaches, resulting in products that are more maintainable and modifiable</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td>- Can be difficult for personnel with a structured design background</td>\n</tr>\n<tr>\n<td></td>\n<td>- Unless a recognized object-oriented method is chosen (for example, Booch, OMT), CASE tool support is limited or nonexistent</td>\n</tr>\n<tr>\n<td>Most appropriate when ...</td>\n<td>Reusability, maintainability, or modifiability of the products developed is an important objective (The consensus of NASA personnel who have applied object-oriented methods is that object-oriented technology is applicable in most situations.)</td>\n</tr>\n<tr>\n<td>Key products</td>\n<td>Software design specification (SWDS), including the following:</td>\n</tr>\n<tr>\n<td></td>\n<td>- Refined object diagrams</td>\n</tr>\n<tr>\n<td></td>\n<td>- Traceability matrices (maps software design components to software requirements)</td>\n</tr>\n</tbody>\n</table>\n\n\n**Recommended techniques**\n\nThe same techniques recommended in Section 5.2.1 (Software CI Requirements Definition and Analysis) are often useful in defining and evaluating alternative software CI designs.\n\n**Tailoring Guidance for the Design Activity**\n\nWhen there is a high level of design reuse, the architectural design probably already exists and need not be considered a separate element of the design activity. However, be sure to highlight changes from the reused architectural design.\n\n---\n\n**TIPS**\n\n- When requirements are especially volatile, increase the rigor of traceability between requirements and design. If there is a change in requirements, then the affected design areas can be identified quickly.\n\n- Include experts in the implementation language, operating system, and other specialties as appropriate in reviewing the design; they each can provide important input regarding their areas of expertise.\n\n- NASA has had considerable success using team inspections (see Table 5-22 and Reference 13) for V&V of design products.\n\n---\n\n**5.2.3 Software CI Implementation and Testing**\n\nThis activity consists of two essential elements:\n\n1. Implementation and unit testing\n2. Integration and testing\n5.2.3.1 Software Implementation and Unit Testing\n\nActivity Requirements\n\nSoftware Implementation and Unit Testing\n\nObjective. The objectives of software implementation and unit testing are (1) to convert the software design into computer programs and computer databases and (2) to test the software at a low level (unit level). (Units may be screens, file formats, reports, etc., as well as source code-oriented components. They also include NDI components.)\n\nKey elements, roles, and responsibilities. This activity consists of two fundamental steps: implementation and unit testing.\n\n- Implementation. Software implementers develop and record software corresponding to each software unit identified in the software CI design. This activity includes, as applicable, designing the unit, coding computer instructions and data definitions, building databases, populating databases and other data files with data values, and performing other activities needed to implement the design. Software units in the design might or might not have a one-to-one relationship with the code and data entities (routines, procedures, databases, data files, and so forth) that implement them or with the computer files that contain those entities. For example, Ada units may comprise more than one code entity. New and modified unit designs and new and modified hand-coded software units undergo inspection in accordance with Section 5.2.6, Software Product Validation and Verification.\n\n- Unit testing. Unit testing verifies a unit’s logic, computations, functionality, and error handling. Newly developed or extensively modified units undergo unit testing. Conduct unit testing only after the code has been certified. Units may be tested in isolation or in conjunction with other units. (Define, in the software plan, the overall unit testing approach to be used.) A test plan written by the unit tester (usually the same person as the unit implementer) provides informal guidelines. The unit tester prepares the test data and any necessary drivers or stubs, and then executes the test plan to verify logic paths, error conditions, and boundary conditions. The unit tester verifies each unit’s designed functions, internal code paths, and error handling in accordance with the unit test approach defined in the test plan. Software implementers and software unit testers analyze the results of unit testing and record the test and analysis results in appropriate product V&V record files. Software implementers revise the software as necessary, and software unit testers perform necessary retesting; they also update other software products (for example, unit-level designs) as needed, based on the results of unit testing. When the unit tester is the implementer, a peer usually reviews test results for accuracy and completeness, then certifies the tested unit.\n\nCOTS, GOTS, reused, and other NDI software products also undergo some level of V&V and preparation for integration, as defined in the software plan. (Refer to Appendix Appendix C. for more specific guidance in testing or evaluating NDIs.)\n\nPrimary products. The primary products from this activity are as follows:\n\n- Unit-level design revisions\n- Unit-level test plans, procedures\n- Unit-tested software\n- Product V&V records for implementation and unit testing products\nRecommended testing methods\n\nBecause software testing is a key element in several required software engineering activities and because different testing methods are appropriate in different situations, the proven testing methods are summarized in one section of this handbook, Section 5.2.6, Software Product Validation and Verification.\n\nTailoring Guidance for Unit Testing\n\nThe formality and rigor of unit testing will vary depending on the unit’s complexity and criticality. Units that are especially complex or critical may need to be tested in isolation, using test drivers and stubs. Otherwise, the testing may be conducted on a collection of related units, perhaps in conjunction with integration testing. Select the level of formality and rigor that is most appropriate and cost-effective for the project as a whole or for various parts of the system.\n\nTIPS\n\n- Use path coverage testing for control units; use functional testing (black box and white or clear box) for algorithmic units.\n- For high-reuse systems, concentrate unit testing activities on new and modified components.\n5.2.3.2 Software Integration and Testing\n\nActivity Requirements\n\nSoftware Integration and Testing\n\nObjective. The objectives of software integration and testing are (1) to integrate the software components, which have been tested at a low level (unit level), into the software product at increasingly higher levels of integration and (2) to V&V the resulting software product.\n\nKey elements, roles, and responsibilities. Integration and testing means integrating the software corresponding to two or more software components, testing the resulting software aggregate to ensure that it works together as intended, and continuing this process until all planned software in each software CI is integrated and tested. Integration testing (also referred to as module, string, and thread testing) verifies the internal integrity of a collection of logically related units (that is, a module), checks the module’s external interfaces with other modules, data files, external input and output, etc., and verifies the designed functions of logical groups of components. (Some integration and testing may take place during unit testing. The requirements outlined in this subsection are not meant to duplicate those activities.)\n\n- Although a formal test plan is sometimes not required, integration testing is more carefully controlled than unit testing, thus at least an informal test plan is needed. Software integrators and testers establish test plans in terms of inputs, expected results, and V&V criteria. The test plans cover all aspects of the software CI architectural design. Software integrators and testers perform integration and testing in accordance with the integration test plans and procedures.\n\n- During integration testing, the software is slowly built up by adding a few units at a time to a core of modules that have already been integrated. Integration testing is usually performed by the implementers responsible for the components being integrated. Software implementers and software integrators and testers analyze the results of integration and testing, and record the test and analysis results in appropriate product V&V record files. Software implementers revise the software as necessary, and software integrators and testers perform necessary retesting. They update other software products (for example, software design documents) as needed, based on the results of integration and testing.\n\n- The last stage of this testing is software implementation team-internal software CI testing, which approximates software CI qualification testing.\n\n- Conduct the following support activities in conjunction with this activity:\n - Finalize the products of this activity by holding milestone reviews in accordance with Section 5.2.9, Milestone Reviews.\n - Control products of this activity in accordance with Section 5.2.7, Software Configuration Management.\n\nPrimary products. The primary products from this activity are as follows:\n\n- Integration and test plans, procedures\n- Integrated, tested software\n- Product V&V records for integration and testing products\n- Milestone review of readiness for qualification testing\nRecommended integration methods\n\n- Top-down method (Table 5-18)\n- Bottom-up method (Table 5-19)\n- Functional path method (Table 5-20)\n\n**Table 5-18. Top-Down Method**\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Integration follows a top-down approach, where lower level modules are added to the top-level driver, level by level, until all components have been integrated and tested.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>Integrated, tested system can be used as drivers (does not need drivers for higher level calling routines)</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td>Needs stubs for lower-level called components until the real components become available</td>\n</tr>\n<tr>\n<td><strong>Most appropriate when ...</strong></td>\n<td>- Architectural design is broad and shallow (for example, transaction processing)</td>\n</tr>\n<tr>\n<td></td>\n<td>- Emphasis is on high-level interfaces</td>\n</tr>\n<tr>\n<td></td>\n<td>- Using high-level NDls</td>\n</tr>\n<tr>\n<td></td>\n<td>- Beginning to integrate</td>\n</tr>\n<tr>\n<td></td>\n<td>- There is risk or uncertainty regarding the architectural design</td>\n</tr>\n</tbody>\n</table>\n\n**Table 5-19. Bottom-Up Method**\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Integration follows a bottom-up approach, where low-level components are integrated and tested with other low-level components, which are then integrated and tested with other low-level components, and so on until all components have been integrated and tested.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>Does not need stubs for lower level called components</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td>Needs drivers for higher level calling routines until the real components become available</td>\n</tr>\n<tr>\n<td><strong>Most appropriate when ...</strong></td>\n<td>- Architectural design is narrow and deep (for example, scientific systems)</td>\n</tr>\n<tr>\n<td></td>\n<td>- Working on utility components</td>\n</tr>\n<tr>\n<td></td>\n<td>- Working on standalone algorithmic components</td>\n</tr>\n<tr>\n<td></td>\n<td>- Using low-level NDls</td>\n</tr>\n<tr>\n<td></td>\n<td>- Beginning to integrate</td>\n</tr>\n</tbody>\n</table>\nTable 5-20. Functional Path Method\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>An end-to-end functional path (or thread) is constructed, to which other modules are then added, until all components have been integrated and tested.</th>\n</tr>\n</thead>\n</table>\n| Advantages | • Tests functions or objects in context \n | • Helps assure that functional requirements are being addressed \n | • Requires fewer drivers, since the only driver required is the one needed to initiate the thread |\n| Disadvantages | Harder to ensure complete testing coverage |\n| Most appropriate when ... | • Making enhancements to an existing system \n | • Verifying end-to-end data flows \n | • Integration has progressed to the point where there is an existing structure to build into \n | • Architectural design is object-oriented |\n\n**Recommended testing methods**\n\nRefer to Section 5.2.6, for a discussion of recommended testing methods.\n\n**Tailoring Guidance for Integration Testing**\n\nJust as described for unit testing, the formality and rigor of integration testing will vary depending on the module's complexity and criticality. Modules that are especially complex or critical may need to be tested in isolation, using test drivers and stubs. Otherwise, the testing may be conducted on a collection of related modules. Select the level of formality and rigor that is most appropriate and cost-effective for the project as a whole or for various parts of the system.\n\n**TIPS**\n\nFor high-reuse systems, concentrate integration testing activities on new and modified components.\n5.2.4 Software CI Qualification Testing\n\nActivity Requirements\n\nSoftware CI Qualification Testing\n\nObjective. Software CI qualification testing independently verifies that software CI requirements have been met and that the software contains its assigned functionality. (This testing is similar to testing performed in the final stage of software integration and testing.)\n\nKey elements, roles, and responsibilities. Software qualification testers are responsible for this activity. They are not the same persons who performed detailed design or implementation of a particular software CI, although the designers and implementers may contribute to the process, for example, by contributing test plans that rely on their knowledge of the software CI’s internal implementation.\n\n- Software qualification testers define and record the test preparations, test plans, and test procedures to be used for software CI qualification testing and the traceability between the test plans and the software CI requirements. They prepare or acquire the test data needed to carry out the test plans and notify the client in advance of the time and location of software CI qualification testing.\n- Software qualification testers perform software CI qualification testing of each software CI in accordance with the software CI test plans and procedures.\n- Software implementers and software qualification testers analyze the results of software CI qualification testing and record the test and analysis results (including software problem reports) in appropriate product V&V record files.\n- Software implementers revise software as necessary. Software qualification testers conduct necessary retesting and update other software products as needed, based on the results of software CI qualification testing.\n- Conduct the following support activities in conjunction with this activity:\n - Finalize the products of this activity by holding milestone reviews in accordance with Section 5.2.9.\n - Control products of this activity in accordance with Section 5.2.7.\n\nPrimary products. The primary products from this activity are as follows:\n- Qualification test plan, procedures\n- Qualification tested software\n- Product V&V records for software qualification testing products\n\nRecommended methods\n\nRefer to Section 5.2.6 for a discussion of recommended testing methods.\n5.2.5 Preparing for Software Delivery\n\nActivity Requirements\n\nPreparing for Software Delivery\n\nObjective. Package the software and accompanying documentation for delivery to either the customer (if the software CI is the final product) or to the NASA group responsible for integrating software and hardware CIs into a higher level system.\n\nKey elements, roles, and responsibilities. The software configuration manager prepares the software delivery package for delivery to either the customer (if the software CI is the final product) or to the NASA group responsible for integrating software and hardware CIs into a higher level system. The QA representative usually provides an additional check that the package is complete and accurate. The software delivery package includes a delivery letter with version description, the software, and associated documentation, including all applicable items in the software delivery package documentation standard. (If software is developed in multiple releases, the software plan identifies the software to be delivered in each release.)\n\n- Prepare the version description. The software configuration manager prepares the version description, which includes the following components:\n - List of requirements met by the delivered software\n - Version identification of software and documentation to be delivered\n - Build instructions\n - Special operating instructions\n - List of resolved problem reports and change reports\n - List of unresolved problem reports\n\n- Prepare the software. The software configuration manager prepares the source files and executable software to be delivered, including any batch files, command files, data files, or other software files needed to regenerate, install, and operate the software on its target computer(s).\n\n- Prepare the as-built software design documentation. Produce this information if the customer requires that it be delivered or if software team personnel will maintain the software CI. The software team updates the design specification of each software CI to match the as-built software. The information includes all applicable items in the SWDS documentation standard.\n\n- Prepare the software user’s information. Produce this information if the customer requires that it be delivered or if software team personnel will operate the software CI. The software team identifies and records information needed by users of the software (persons who will operate the software and persons who will make use of its results). The information includes all applicable items in the software user’s guide documentation standard.\n\n*Activity requirements continued on next page*\n**Activity requirements continued**\n\nRequirements for documentation may be satisfied by substituting commercial or other manuals that contain the required information. The documentation identified in this section is normally developed in parallel with software engineering and is ready for use in software CI testing.\n\n- Conduct the following support activity in conjunction with this activity:\n - Control products of this activity in accordance with Section 5.2.7, Software Configuration Management.\n\n**Primary products.** The primary products from this activity is a software delivery package that includes the following:\n\n- Delivery letter with version description\n- The software (executable software, software source files)\n- Accompanying documentation (as-built software design documentation, software user’s guide)\n### 5.2.6 Software Product Validation and Verification\n\nNote: Recall that this is the first of four sections describing the group of support engineering activities shown in Figure 5–8. (See the beginning of Section 5.2.)\n\n#### Activity Requirements\n\n**Software Product Validation and Verification**\n\n**Objective.** Independently evaluate software products to ensure they meet all requirements imposed on them (functional and performance requirements as well as product standard requirements).\n\n**Key elements, roles, and responsibilities.**\n\n- Software team members perform in-process V&V of the software products generated in carrying out the requirements of this guidebook. Software products are evaluated against their specifications or requirements at each stage of the product’s evolution (see 21) to ensure that the right product is being built and the product is being built right. The two primary methods used for software product evaluation are peer reviews (for paper-oriented products) and testing (for executable products). The software products to be evaluated are identified in this guidebook in conjunction with each of the engineering activity descriptions.\n\n- The persons responsible for evaluating a software product are not the persons who developed the product; although the persons who developed the software product may be involved, for example, as participants in a walkthrough of the product before, or as a part of, its inspection.\n\n- Software team members prepare records of each software product V&V and the project maintains those records for the life of the project. Software product V&V records include (but are not limited to) inspection and certification records (when the V&V method is inspection) and problem and test reports (when the V&V method is testing). Problems in software products under configuration control at the project level or higher are handled as described in Section 5.2.7, Software Configuration Management.\n\n**Primary products.** The primary products from this activity are software product V&V records, including the following minimum information:\n\n- Identification of the product evaluated\n- Product V&V method used\n- Criteria used in the V&V\n- Problems identified in the product (These are variously referred to as SPRs (system or software problem reports), STRs (system or software trouble reports), DRs (discrepancy reports), and IDR (internal DR).)\n- Final resolution of the problems\n- Certification that the product satisfies V&V criteria\n### Table 5-21. Software Product V&V Summary\n\n<table>\n<thead>\n<tr>\n<th>Software product</th>\n<th>... is evaluated against (at least) the following requirements or design specification</th>\n<th>... usually using the following product V&V method(s)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Software requirements specification (SWRS)</td>\n<td>System requirements allocated to the software CI</td>\n<td>Walkthroughs; document reviews; inspection</td>\n</tr>\n<tr>\n<td>Software design specification (SWDS)</td>\n<td>SWRS</td>\n<td>Walkthroughs; document reviews; inspection</td>\n</tr>\n<tr>\n<td>Unit-level design specifications</td>\n<td>SWDS (detailed design)</td>\n<td>Inspection (per unit design certification criteria)</td>\n</tr>\n<tr>\n<td>Unit-level code</td>\n<td>Unit-level design specifications</td>\n<td>Inspection (per unit code certification criteria)</td>\n</tr>\n<tr>\n<td>Integrated sets of units (modules) up to the CI level</td>\n<td>SWDS (detailed design)</td>\n<td>Integration testing (also known as module, string, thread testing) (per integration test plan)</td>\n</tr>\n<tr>\n<td>Software CI build</td>\n<td>Initially, based on SWDS; later, evolving toward SWRS</td>\n<td>Build qualification testing (BQT) (per BQT plan)</td>\n</tr>\n<tr>\n<td>Software CI release</td>\n<td>Initially, based on SWRS; later, evolving toward system requirements allocated to the software CI</td>\n<td>Formal (release) qualification testing (FQT) (per FQT plan)</td>\n</tr>\n<tr>\n<td>Software delivery to customer</td>\n<td>System requirements allocated to the software CI</td>\n<td>Acceptance testing (AT) (per AT plan; when the system is a software system, FQT is the AT)</td>\n</tr>\n</tbody>\n</table>\n\n### Recommended methods\n\n- Peer review methods\n - Inspection method (Table 5–22)\n - Walkthrough method (Table 5–23)\n - Document review method (Table 5–24)\n - Demonstration method (Table 5–25)\n\n- Testing methods\n - Functional (black box) testing (Table 5–26)\n - Structural (white or clear box) or coverage (statement, branch, or path) testing (Table 5–27)\n - Statistical testing (Table 5–28)\n - Regression testing (Table 5–29)\n - Cleanroom (Table 5–31)\n### Table 5–22. Inspection Method\n\n| Summary Description and Discussion | Inspections are well-defined peer reviews that are intended to verify correctness, quality, and compliance with requirements and standards. There are two types of inspection: One-on-one and team. A one-on-one inspection relies on a single inspector; team inspections include two or more. (However, studies conducted within NASA as well as other parts of the software industry clearly show that two or more inspectors are far more effective in discovering defects than a single one (Reference 14).) The primary use of inspections is to find defects; secondary uses include exposing team members to details of other parts of the system, helping increase awareness of the importance of paying attention to details when creating products, helping more junior personnel identify more subtle defects, and increasing the skills of junior personnel by exposing them to the techniques used by more senior staff members. Product certification is used as input to the project's progress measurement process. Defects found by inspections (which are recorded on inspection and certification records) are used as input to the defect causal analysis process. |\n| Advantages | Very thorough |\n| Disadvantages | Sometimes misapplied—either focuses only on minor defects, such as formatting issues, or done as a formality to certify a product after informal peer reviews have already been performed and no further defects are known. |\n| **Most appropriate when ...** | • Overall development time is tight \n• Time allocated to higher level testing is tight \n• Product quality goals are high |\n| Key products | • Inspection and certification records (software product V&V records) \n• Inspection data collection forms |\n\n### Table 5–23. Walkthrough Method\n\n| Summary Description and Discussion | Walkthroughs are primarily a method for communicating information to team members. Walkthroughs are not intended to be a defect-finding tool; however, obvious problems are sometimes identified during a walkthrough. |\n| Advantages | Quick, effective, relatively informal method for sharing information with peers. |\n| Disadvantages | Sometimes used in place of inspection method (walkthroughs are not nearly as thorough as inspections; defects are likely to escape detection until later in the life cycle, when effort to repair is greater). |\n| **Most appropriate when ...** | Information needs to be communicated to others. |\n| Key products | • Comments from team members \n• Questions to be answered \n• Action items |\n### Table 5-24. Document Review Method\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Document reviews are peer reviews of a finished document that are intended to verify completeness, correctness, consistency, quality, and compliance with standards</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>Enables review of all parts of a document in context with each other</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td>Review is not performed until the document is complete (or nearly complete)</td>\n</tr>\n<tr>\n<td>Most appropriate when ...</td>\n<td>A complete document must be reviewed</td>\n</tr>\n<tr>\n<td>Key products</td>\n<td>Review and certification records (software product V&V records)</td>\n</tr>\n</tbody>\n</table>\n\n### Table 5-25. Demonstration Method\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Demonstrations are most frequently used in conjunction with prototypes. The purpose of a demonstration is to solicit feedback from another group (for example, end users of the product).</th>\n</tr>\n</thead>\n</table>\n| Advantages | • Facilitates early evaluation of product characteristics in terms of product’s look and feel \n• Encourages customer and end user participation |\n| Disadvantages | • Effective demonstrations require careful preparation (that is, they take extra time and effort) \n• May lead customer and end users to believe that product is (almost) done \n• Evaluation may occur later in phase than would occur using other methods \n• Can lead to requirements growth in terms of nice-to-have features |\n| Most appropriate when ... | Alternative approaches need to be evaluated (for example, user interface techniques) |\n| Key products | • Prototypes \n• Demonstration summary, results, or agreements |\nTable 5-26. Functional Testing Method\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>In functional testing, sometimes referred to as black box testing, verifying functionality and correct interfacing of software components is the focus. The tester does not need to understand the internal design of the software component(s) under test, nor how it is implemented—simply what the software is expected to do. Functional testing is often organized based on threads of software components that accomplish a higher level function, and is sometimes based on operational scenarios. NASA software testers have found tests based on operational scenarios to be very effective at uncovering errors.</th>\n</tr>\n</thead>\n</table>\n| **Advantages** | • Not overly time-consuming \n• Ensures that functional requirements are tested \n• Can be performed by testers without detailed knowledge of design of the software |\n| **Disadvantages** | • Less likely to detect defects in parts of software that are not frequently executed \n• Identifies symptoms of defects, not necessarily their causes \n• Robustness of product is not established |\n| **Most appropriate when ...** | A primary objective of the testing is to verify \n• Satisfaction of requirements \n• Correct interfacing of components |\n| **Key products** | • Test plans and procedures, including traceability to design or requirements specification (see Table 5-21) \n• Test records (software product V&V records) |\n### Table 5-27. Structural or Coverage Testing Method\n\n| Summary Description and Discussion | Structural testing, sometimes referred to as clear box or white box testing, is testing in which verification of correct implementation of the software design is the focus. The tester must understand the internal design of the software component(s) under test. Coverage testing is a specific form of structural testing that is designed to ensure that each statement or logic path or software component is executed at least once. |\n| Advantages | • Increases confidence in structure of design and correct implementation of the design \n• More likely (than functional testing) to identify causes of problems |\n| Disadvantages | • Very time-consuming \n• May miss aspects of functionality and of the \"big picture\" \n• Requires in-depth understanding of software internals \n• Sometimes difficult to force certain conditions |\n| Most appropriate when ... | • A primary objective of the testing is to verify correct implementation of the software design \n• A primary objective of the testing is to verify thorough exercise of all the software paths \n• Lower level component testing is being performed (that is, unit level or integration level) \n• Control-oriented or safety-critical components are being tested |\n| Key products | • Test plans and procedures, including traceability to design or requirements specification (see Table 5–21) \n• Test records (software product V&V records) |\n\n### Table 5-28. Statistical Testing Method\n\n| Summary Description and Discussion | Statistical testing is testing based on a detailed assessment of expected usage profiles of characteristics of the software that are especially important to the customer. Such characteristics include assessing which software components will be executed most often, which components can cause catastrophic results if defects are present, etc. Statistical testing is usually based on operational scenarios. |\n| Advantages | Concentrates testing effort on parts of the software that are most important to the customer |\n| Disadvantages | • Requires an in-depth understanding of how the software will be used operationally \n• Increases possibility that defects will remain undiscovered in less frequently exercised parts of the software |\n| Most appropriate when ... | • Testing efficiency is at a premium \n• Testing period is at a minimum |\n| Key products | • Test plans and procedures, including traceability to design or requirements specification (see Table 5–21) \n• Test records (software product V&V records) |\nTable 5–29. Regression Testing Method\n\n| Summary Description and Discussion | Regression testing is retesting previously tested software after some kind of change has been made. Changes may have been made in the software itself, or in other software or hardware with which the software interfaces. The purpose of regression testing is to verify that the changes have not adversely affected previously tested software. Regression testing does not usually include rerunning all test cases that were originally used, but instead a predefined subset of the test cases that are selected based on criteria established by the project team and the customer. |\n| Advantages | • Promotes confidence in an evolving product \n• Ensures that obvious defects have not been introduced into the product |\n| Disadvantages | If regression test sets are not chosen carefully, \n• Considerable effort can be expended if testing is overly exhaustive \n• Defects can go undetected if testing is too superficial |\n| Most appropriate when ... | Changes are made to software that has undergone higher levels of testing (that is, integration level or qualification level) |\n| Key products | Test records (software product V&V records) |\n\nOne large NASA organization has found over the past few years that the methods summarized in Table 5–30 have been used most often for unit-level, integration-level, and qualification-level testing.\n\nTable 5–30. Testing Methods vs. Testing Levels\n\n<table>\n<thead>\n<tr>\n<th>Testing Method</th>\n<th>Unit Level Testing</th>\n<th>Integration Level Testing</th>\n<th>Qualification Level Testing</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Functional</td>\n<td>✔</td>\n<td>✔</td>\n<td>✔</td>\n</tr>\n<tr>\n<td>Structural</td>\n<td>✔</td>\n<td>✔</td>\n<td></td>\n</tr>\n<tr>\n<td>Coverage</td>\n<td>✔</td>\n<td>✔</td>\n<td></td>\n</tr>\n<tr>\n<td>Statistical</td>\n<td>✔</td>\n<td>✔</td>\n<td>✔</td>\n</tr>\n<tr>\n<td>Regression</td>\n<td>✔</td>\n<td>✔</td>\n<td>✔</td>\n</tr>\n</tbody>\n</table>\n\nThe Cleanroom method (Reference 15) is an alternative approach that has been used successfully on some NASA projects (Reference 16).\nThe Cleanroom method provides an alternative to traditional testing, with a\ngoal of preventing software errors rather than detecting them. Developed at\nIBM in the late 1980s, Cleanroom relies on human discipline and intellectual\ntest control to build quality into the final product instead of on computer-aided\nprogram debugging to detect and remove errors.\n\n### Advantages\n\nSuccessful application of the Cleanroom methodology can significantly\nincrease software quality and reliability, decrease test and debug time, and\nminimize rework efforts.\n\n### Disadvantages\n\nMay not be applicable to large projects.\n\n### Most appropriate when...\n\n- Coders and testers can be split into two separate teams\n- Software system size is less than approximately 50,000 lines of code\n\n#### Tailoring Guidance for Software Product V&V\n\nSelect or adjust the product V&V methods based on the customer’s goals and objectives for cost,\nschedule, and product qualities. For example,\n\n- If high robustness or reliability is called for\n - Increase the amount of peer review and testing\n - Increase the degree of independence of the evaluators from the developer\n- If less robustness or reliability is acceptable\n - Have peer reviews and testing focus on those portions of the system that are\n expected to have high use or are especially critical\n\nRefer to Appendix Appendix C. for guidelines for evaluating NDIs. (Examples of procedures for\nV&V can be found in Reference 17.)\n\n#### TIPS\n\n- Make NDI V&V results reports available for other software\n projects; submit them to your organization’s PAL.\n- Use product certification as the completion criterion for\n progress measurement.\n- Store software product V&V records using an approach that\n facilitates easy retrieval and data collection.\n5.2.7 Software Configuration Management\n\n**Activity Requirements**\n\n**Objective.** Ensure that the integrity of a software product is known and preserved through its development and maintenance.\n\n**Key elements, roles, and responsibilities.** Software configuration management in each build takes place in the context of the software products and controls in place at the start of the build.\n\n*Configuration Identification*—The software requirements analysts and design architects work with the software configuration manager to identify software CIs, identify the subordinate entities (or categories of entities) to be placed under configuration control, and assign a project-unique identifier to each software CI and subordinate entity to be placed under configuration control. These entities include the software products to be developed or used by the software team. The identification scheme is geared to the level at which entities (for example, computer files, electronic media, documents, software units) will actually be controlled. The identification scheme includes a description or specification of the version, revision, or release status of each entity.\n\n*Configuration Control*—The software configuration manager establishes and implements procedures defining\n\n- The conditions under which each identified entity (or category of entity) is initially placed under control\n- The levels of control through which each entity must pass (for example, author control, project control, customer control)\n- The packaging, storage, handling, and delivery of controlled software products\n- The mechanisms used to track problems reported in, and changes requested to, controlled software products\n- The steps to be followed to request authorization for changes, to process change requests, to track changes, to distribute changes, and to maintain past versions\n- The persons or groups with authority to authorize changes and to make changes at each level (for example, software implementer, software manager, client)\n\nChanges that affect an entity under customer control are proposed to the customer in accordance with established procedures.\n\n*Configuration Status Accounting*—The software configuration manager maintains records of the configuration status of all entities that have been placed under configuration control at the project level or higher. These records are maintained for the life of the project. They include, as applicable, the current version, revision, or release status of each entity, a record of changes to the entity since it was placed under configuration control, and the status of problem reports and change requests that affect the entity.\n\n*Activity requirements continued on next page*\nTailoring Guidance for the SCM Activity\n\nLevels of Control—There are two fundamental levels of software product change control: baseline control (or configuration management) and local control. Apply the appropriate level and type of control to verified products—intermediate as well as delivered, new as well as changed from previously controlled versions.\n\nBaseline Control. Some software products, for example, the software requirements, design, and code, should have baselines established at predetermined points. These baselines are reviewed and agreed on with the customer, and serve as the basis for further development. Baselines are typically established in conjunction with milestone reviews, such as SSR (software requirements), CDR (software design), and following software CI qualification testing and physical configuration audit (PCA) or functional configuration audit (FCA) (code). Apply a rigorous change control process to baselined items.\n\nLocal Control. Some software products, such as the software plan, may not need to be placed under baseline control, but still need to be controlled locally. This implies that the version of the product in use at a given time (past or present) is known (that is, version control), and changes are incorporated in a controlled manner (that is, change control). For example, software plans are typically placed under local control, but not baseline control.\n\nThe specific change control approach used by a software project will vary based on many factors. On some projects, the customer is responsible for some or all SCM functions; in other cases, the software team is responsible; and sometimes the responsibilities are split (for example, requirements documents might be controlled by the customer, but design documents might be under local control until the CI is delivered). Similarly, the configuration review function for a large project might require a formal configuration control board (CCB) while the CCB for a four-\n\nActivity requirements continued\n\nConfiguration Audits—For software CI releases that are to become operational, the software configuration manager or QA representative conducts two types of audits of the software CI after it has finished software CI qualification testing but before delivery:\n\n- Physical configuration audit—this audit verifies that the software conforms to its technical documentation and does not contain unauthorized changes\n- Functional configuration audit—this audit verifies that the software CI meets all the requirements allocated to it\n\n(Planning for SCM is included as part of the software project planning activity. The SCM plan (approach) may be physically included in the project’s software plan or may be packaged separately. The software configuration manager works with the software manager in creating and maintaining the SCM plan.)\n\nPrimary products. The primary products from this activity are as follows:\n\n- Software configuration management approach (part of the software plan), which includes identification, control, status accounting, and audits\n- Controlled software products\n- Software configuration management records\nperson development project might be simply the software project manager and a customer representative.\n\nEach project’s product control approach is defined in the SCM portion of its software plan and specifies which products are to be placed under baseline control and which will be under local control. The approach defines what products will be controlled, under what conditions each kind of product is initially placed under control, who controls it and where, and what has to occur to change it.\n\n*Configuration Audits*—It may not be necessary to perform FCAs or PCAs at CI level, they may be done at higher level (for example, system or release). Nor is it necessary to perform FCAs and PCAs separately, they may be done together on a system level. (Reference 17 includes examples of procedures for FCAs and PCAs.)\n\n*Requirements Management*—While a software product’s requirements are only one of several subordinate entities that must be controlled, they are emphasized here because everything that the software team does is based on those requirements. Poor management of requirements has caused problems in the past.\n\nIf the customer does not require or maintain any form of software requirements specification, the software team should document and control (to whatever degree of formality is deemed appropriate) the product’s requirements as they understand them and as they are being implemented. The customer should be given a copy of these software requirements to help ensure that the software team and the customer have a common understanding of the basis for the end software product. The requirements should be kept up to date in a controlled fashion.\n\n### TIPS\n\n- Identify products to be controlled early, but avoid placing products under control too soon.\n- Generally, conduct PCAs and FCAs in conjunction with each other.\n- The more builds or releases, the greater the importance of change control.\n- The more activities that are going on in parallel (especially build or releases), the greater the importance of change control.\n5.2.8 Software Quality Assurance\n\nActivity Requirements\n\nObjective. Independent SQA is performed throughout the duration of the project to provide confidence to management that approved processes are being followed and that high-quality products are being produced.\n\nKey elements, roles, and responsibilities. SQA is performed by a QA representative who is organizationally independent of the software project and has the skills, responsibility, authority, and organizational freedom to permit objective software product and process evaluations. (The quality of the software product is the responsibility of the entire software team.3)\n\nThe QA representative does the following:\n- Ensures that each activity identified in the software plan is performed in accordance with the plan\n- Ensures that each software product identified in the software plan is prepared and undergoes software product V&V and corrective action as defined in the plan\n- Prepares records of software quality assurance activities and maintains those records for the life of the project\n- Provides recommendations for process and product improvement to the software manager and software team\n\n(Planning for SQA is included as part of the software project planning activity. The SQA plan or approach may be physically included in the project’s software plan or may be packaged separately. The QA representative works with the software manager to create and maintain the SQA plan. The QA representative performs SQA activities in accordance with the SQA plan.)\n\nPrimary products. The primary products from this activity are as follows:\n- SQA approach (part of the project’s software plan)\n- SQA records\n\nRecommended Methods\n- Auditing, monitoring, and assessing performance of activities and qualities of products\n\n---\n\n3 In some environments, the term SQA is used to refer to more than “independent assurance of software products and process”; that is, it sometimes includes peer reviews, testing, etc. This guidebook, however, restricts the SQA activity to include only independent assurance; peer reviews, testing, etc. are included under the Software Product V&V activity.\n5.2.9 Milestone Reviews\n\nActivity Requirements\n\nMilestone Reviews\n\nObjective. Jointly, that is, with customer and software team participation, (1) make a final review of a completed product as a basis for its approval, (2) review readiness to proceed to the next phase of engineering, and (3) identify project-level issues and initiate corrective actions.\n\nKey elements, roles, and responsibilities. Milestone reviews are typically associated with life-cycle phases and are usually used to conclude one phase and transition to the next. They are not intended to serve as product V&V; product V&V is assumed to have been performed throughout preparation of the product(s) being reviewed at the milestone review. The software manager and customer plan, and the software team takes part in, milestone reviews. Candidate milestone reviews are listed in Table 5–32. There are two distinct aspects to milestone reviews: technical and management.\n\nTechnical aspect—The key role in the technical aspect of milestone reviews is fulfilled by persons who have technical knowledge of the software products that are the subject of the review. Their objectives are as follows:\n\n- Review final software products to establish an SCM baseline\n- Provide insight and obtain feedback on the technical effort; surface and resolve technical issues\n- Assess project status; identify and discuss near- and long-term risks regarding technical issues\n- Agree on mitigation strategies for identified risks, within the authority of the technical participants\n- Identify risks and issues to be addressed by management (that is, those discussed under Management aspect, below)\n- Ensure ongoing communication between customer and software team technical personnel\n (It is assumed that the customer’s technical representatives have reviewed the subject products in advance.)\n\nManagement aspect—The key role in the management aspect of milestone reviews is fulfilled by persons with authority to make cost, schedule, and resource allocation decisions. Their objectives are as follows:\n\n- Inform upper management about project status, directions being taken, technical agreements reached, and overall status of evolving software products\n- Resolve issues that could not be resolved by technical participants\n- Agree on mitigation strategies for near- and long-term risks that could not be resolved by technical participants\n- Identify and resolve management-level issues and risks not raised within technical aspect\n- Obtain commitments and customer approvals needed for timely accomplishment of the project\n\nActivity requirements continued on next page\nActivity requirements continued\n\nPrimary products. The primary products from this activity are as follows:\n\n- The milestone review event itself\n- Action items resulting from the review (for example, develop a strategy to mitigate a risk identified during the review)\n- Approved product(s)\n- Approval to proceed to next phase\nTable 5-32. Candidate Milestone Reviews\n\n<table>\n<thead>\n<tr>\n<th>Review</th>\n<th>Objective</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Concept or contents reviews (SCRs, RCRs)</td>\n<td>The operational concept for a software system or the content of a release.</td>\n</tr>\n<tr>\n<td>Requirements reviews (SRRs, RRRs)</td>\n<td>The specified requirements for a software system, subsystem, or release and to establish the functional baseline.</td>\n</tr>\n</tbody>\n</table>\n| System design reviews (SDRs) | One or more of the following: \n- The system- or subsystem-wide design decisions \n- The architectural design of a software system or subsystem and to establish the system design baseline. |\n| Software specification reviews (SSRs) | The specified requirements (that is, SWRS) for a software CI and to establish the CI-allocated baseline. (SSRs may also be referred to as SRRs when the system is essentially all software.) |\n| Software design reviews (PDRs, CDRs, BDRs, RDRs) | One or more of the following: \n- The software CI-wide design decisions \n- The architectural design of a software CI \n- The detailed design (that is, SWDS) of a software CI or portion thereof (such as a database or an upcoming build) and to establish the CI development baseline. |\n| Test readiness reviews (QTRRs, RQTRRs, ATRRs) | One or more of the following: \n- The status of the software test environment \n- The test cases and test procedures to be used for software CI qualification testing or system qualification testing \n- The status of the software to be tested \nThe reviews that follow software CI qualification testing, PCA, and FCA, but precede the next stage of testing (that is, either system-level integration and testing or system installation and acceptance testing) are held to establish the CI product baseline. |\n| Operational readiness reviews (ORRs) | One or more of the following: \n- The readiness of the software for installation at operational sites \n- The user and operator manuals \n- The software product specifications \n- The software version descriptions \n- The status of installation preparations and activities \n- The status of transition preparations and activities, including transitioning the software development environment (if applicable) to the maintenance organization and to establish the operational baseline. |\n**Recommended Methods**\n\n- Meetings (Table 5-33), for example, the milestone review may be held as the final element of a JAD workshop (see Table 5-15)\n- Presentations (Table 5-34)\n- Demonstrations (Table 5-35)\n\n**Table 5-33. Meetings**\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Meetings come in a wide variety of sizes (for example, length, depth of coverage, number of attendees) and degrees of formality. This variation can be of considerable advantage to the software manager in that he or she can, in conjunction with the customer, establish the most cost-effective structure for the meeting.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n- Usually most efficient and least costly method \n- Easily scheduled and planned \n- More conducive to greater interaction of participants than presentations |\n| Disadvantages | \n- Degree of formality may not be acceptable to the customer \n- Sometimes difficult to control |\n| **Most appropriate when ...** | Agreeable to the customer |\n| Key products | \n- Action items \n- Approved products(s) \n- Approval to proceed to the next phase |\n\n**Table 5-34. Presentations**\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Presentations, like meetings, come in a wide variety of sizes and degrees of formality. Usually, however, additional effort is expended in preparing materials designed expressly for the presentation.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>Involve a larger audience than meetings</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n- Involve a larger audience than meetings \n- Usually more formal than meetings and, therefore, require more preparation effort; for example, may require producing presentation-quality slides, holding dry runs \n- Less conducive to interaction of audience than meetings |\n| **Most appropriate when ...** | Required by the customer |\n| Key products | \n- Action items \n- Approved products(s) \n- Approval to proceed to the next phase |\nTable 5-35. Demonstrations\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>Demonstrations are used to display the current state of the software product or prototypes of the product</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>Instill level of confidence that the project is on the right track</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td>In early life-cycle phases, users may interpret the product to be finished and not recognize (or accept) that additional work is required to develop an operational product</td>\n</tr>\n<tr>\n<td>Most appropriate when ...</td>\n<td>The user interface is crucial, or when a new technology is being applied</td>\n</tr>\n<tr>\n<td>Key products</td>\n<td>• Action items</td>\n</tr>\n<tr>\n<td></td>\n<td>• Approved products(s)</td>\n</tr>\n<tr>\n<td></td>\n<td>• Approval to proceed to the next phase</td>\n</tr>\n</tbody>\n</table>\n\n**Tailoring Guidance for the Milestone Reviews Activity**\n\nMilestone reviews may be conducted incrementally, dealing at each review with a subset of the listed items or a subset of the system or software CI(s) being reviewed.\n\nNMI 7120.4 (Reference 18) establishes management policies and responsibilities for major system program and projects. The companion NASA Handbook (NHB) 7120.5 (Reference 19) indicates that only PDRs and CDRs are required of all major programs. The candidate milestone reviews discussed in this guidebook are recommended, but not required, for all software development and maintenance projects, not only for major programs.\n\n---\n\n4 NMI 7120.4 defines the scope of a “major” program or project.\nTIPS\n\n- Make an effort to understand the customer’s preferred audience for the review, and the perspective from which the review material will be presented.\n- Attempt to have representatives of the end users of the product participate in milestone reviews.\n- Ensure that the method and degree of formality chosen for the milestone review are appropriate for the product(s) being reviewed.\n- Minimize the amount of material created especially for the review; it adds cost and time to the project. Instead, use appropriate portions of the products being reviewed.\n- Review presentation material with the customer in advance.\n- Dry-run presentations. This will help gauge timing, identify loose ends, familiarize the presenters with the material, and help prepare the presentation team for potential issues that might be raised during the actual review.\n- Dry-run demonstrations for the same reasons.\n- Consider holding walkthroughs of the product for the customer during the engineering process (that is, throughout each life-cycle phase before its milestone review) to ensure his or her awareness of the product’s evolution well before the milestone review. (The milestone review should not be the first time that the customer has reviewed the product.)\n6. Finishing the Software Plan—Defining the Management Approach\n\nThe preceding two chapters described how to understand the scope and characteristics of the work to be performed, and how to define an appropriate technical approach to perform the work. This chapter describes the steps needed to define the management approach for the project and to document and review the project’s software plan. (As recommended in Chapter 4, planning should be coordinated, as much as possible, with other groups responsible for related software efforts.)\n\nActivity Requirements\n\n**Defining the Management Approach**\n\n**Objective.** Document the approach that the software manager will use to manage the software engineering effort.\n\n**Key elements, roles, and responsibilities.** The software manager defines the project’s management approach by doing the following:\n\n- Establishing the software project’s organizational structure\n- Estimating and scheduling the work\n- Planning other activities\n- Reviewing the software plan\n\nTo facilitate the development of each project’s management approach and to avoid reinventing the wheel, this guidebook contains a summary of effective, proven, recommended methods from which the software manager can choose to satisfy the required common activities.\n\nIf, however, the manager believes that a different method would be more appropriate, then he or she is encouraged to try it in a controlled fashion. That is, the manager includes a process study of applying the alternative approach to quantitatively assess its overall effect on the software product and process. (See Table 6–5.)\n\nWhenever the software manager feels that additional activities or products would be useful, he or she is expected to apply sound, professional judgment in decisions related to such topics.\n\nEach project’s management approach is defined in its software plan.\n\n**Primary products.** The primary product from this activity is as follows:\n\n- Remaining management approach topics in the project’s software plan\n\nThe rest of this chapter provides guidance in accomplishing this required activity.\n6.1 Establishing the Software Project’s Organizational Structure\n\nActivity Requirements\n\nEstablishing the Organizational Structure\n\nObjective. Define an effective organizational structure to carry out the selected technical approach.\n\nKey elements, roles, and responsibilities. Once the technical approach has been defined, the software manager must define an appropriate organizational structure to carry out the technical approach. Figure 6–1 illustrates a typical NASA software project structure. It depicts the basic roles that are required on a software project. Record in the software plan a description of the planned organizational structure.\n\nPrimary products. The primary product from this activity is as follows:\n- Description of software project structure\n\nWhile Figure 6–1 illustrates a typical NASA software engineering organization, it does not imply that different persons are responsible for each role. Quite the contrary, very often a single individual may assume two or more roles on a typical software project (though care must be taken when assigning personnel to roles in which independence is required). These roles may also be filled by personnel from outside of the software team’s own organization (for example, customer personnel may be responsible for certain roles).\n6.2 Estimating and Scheduling the Work\n\nActivity Requirements\n\nEstimating the Work\n\nObjective. Develop estimates of the size, effort, and schedule duration for the software work.\n\nKey elements, roles, and responsibilities. The software manager estimates product size, effort, and duration in accordance with local standards. Key software team members are often consulted in this activity. Table 6–1 summarizes the three periods for which the software manager develops estimates. Record these estimates in the software plan.\n\nPrimary products. The primary product from this activity is as follows:\n- Estimates of software product size, effort, and schedule duration.\n\n<table>\n<thead>\n<tr>\n<th>Period planned</th>\n<th>Purpose of estimate and plan</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Project, start to finish</td>\n<td>• Provide customer with an estimate and plan for the full software effort.</td>\n</tr>\n<tr>\n<td></td>\n<td>• Ensure thorough high-level analysis of the full software effort.</td>\n</tr>\n<tr>\n<td>Upcoming build</td>\n<td>Ensure thorough detailed analysis of the work to be accomplished in the next build.</td>\n</tr>\n<tr>\n<td>Fiscal year</td>\n<td>Develop plans that reflect the customer’s budget for the fiscal year.</td>\n</tr>\n</tbody>\n</table>\n\nTailoring Guidance\n\nLocal standards for estimating size, effort, and duration are based on models derived from historical records of similar projects developed by the same organization. The basis of a size estimate for software projects, for example, may be actual counts of lines of codes, function points, database transactions, or whatever unit is appropriate for the application domain.\n\nAn example of local standards for estimating can be found in the Manager’s Handbook for Software Development (Reference 7) of the NASA Software Engineering Laboratory (SEL). The SEL derived local estimation standards for all software developed or maintained within the Flight Dynamics Division at GSFC. The SEL’s estimation models are based on the Constructive Cost Model (COCOMO) (Reference 20) but are tailored to the local environment and based on analysis of measurement data collected from software projects since 1976. A detailed explanation of the derivation of the SEL estimation models can be found in the Cost and Schedule Estimation Study Report (Reference 21). Further examples are available in the NASA Software Measurement Guidebook (Reference 5).\n\nTIPS\n\nThe best estimate is still just an estimate. Expect to have to re-estimate as a result of monitoring the status of the project (see Section 7.1.2).\nActivity Requirements\n\nScheduling the Work\n\n**Objective.** Develop a schedule for performing the software engineering activities, identifying when specific products will be delivered, and including a profile of the staffing levels required to perform the work.\n\n**Key elements, roles, and responsibilities.** Table 6–1 summarizes the three periods for which the software manager develops schedules. Scheduling for a system or software CI that is to be developed in multiple builds includes\n\n- Overall planning for the project\n- Detailed planning for the current build\n- Planning for future builds to a level of detail consistent with the information available\n\nThe first step in software build planning is to lay out a series of one or more builds and to identify the objectives of each build. The next step is to schedule the activities in each build. The customer may set forth general milestones and have the software team provide specifics or may provide specific schedules.\n\nRecord in the software plan, the milestone plan and events list, the work breakdown structure, and the staffing plan.\n\n**Primary products.** The primary products from this activity are as follows:\n\n- Milestone plan and events list\n- Work breakdown structure\n- Staffing profile\n\n---\n\n**Recommended techniques**\n\n- Mini-Waterfall\n- Timeboxes\n\n**Table 6–2. Mini-Waterfall**\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>This is the traditional technique for planning builds. That is, each build includes some emphasis on analyzing the requirements allocated to the build, usually includes detailed design of the portion of the software that will be implemented in the build, implementation and testing of the software, and qualification testing of the build.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>Technique is familiar to most managers</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td>Basically the same as those described under Waterfall Life-Cycle Model (Table 5–2) but not as significant in impact; that is, the requirements to be implemented in the build must be known before beginning the build.</td>\n</tr>\n<tr>\n<td>Most appropriate when ...</td>\n<td>The requirements to be implemented in the build are quite stable and well-understood</td>\n</tr>\n</tbody>\n</table>\nTable 6-3. Timeboxes\n\n| Summary Description and Discussion | A timebox refers to a subdivision of a build created to achieve a unit of production that is manageable in size, complexity, staffing, and duration. It is a planning construct that controls functionality delivered by establishing fixed resource and time budgets. That is, when the allocated time and effort have been expended, it is time to move on to the next timebox. |\n| Advantages | Helps avoid \"gold plating\" |\n| Disadvantages | The product resulting from the timebox might not be complete in its own right |\n| Most appropriate when ... | • Functionality is not well-understood or is likely to change considerably \n• Using the evolutionary development life-cycle model \n• Developing prototypes \n• Cycle time is critical |\n\nTailoring Guidance for Planning Builds\n\n- Avoid treating all software CIS as though they must be developed in lock-step, reaching key milestones at the same time. Allowing software CIS to be on different schedules can result in more optimal development.\n- Similarly, avoid treating software components within a CI as though they must be developed in lock-step, all designed by a certain date, implemented by a certain date, etc. Flexibility in the scheduling of software components can also be effective.\n- The required software engineering activities need not be performed sequentially. Several may be taking place at one time, and an activity may be performed continually or as needed throughout a build or across multiple builds. The activities in each build should be laid out in the manner that best suits the work to be done.\n\nTIPS\n\n- If early builds are devoted to prototyping, developing throw-away software to arrive at a system concept or assist in defining system requirements, it may be appropriate to forego certain formalities, such as coding standards, that will be imposed later on the deliverable software. If the early software will be used later, such formalities may be appropriate from the start. These decisions are project dependent and should be recorded in the software plan.\n- Consider making the first build a simple one to get the project off to a good start; that is, to establish confidence in the software team and the customer.\n6.3 Planning Other Activities\n\nActivity Requirements\n\nPlanning Other Activities\n\nObjective. Several other elements must be addressed in the project’s software plan:\n\n- Team training\n- Risk management\n- Technical performance measurement\n- Process improvement initiatives\n- Management measures\n\nKey elements, roles, and responsibilities.\n\nPlan for Team Training—The software manager is responsible for determining the project-specific training needs of his or her team with respect to the application area, new technologies to be employed, etc. Training is usually planned to be delivered just in time to support the team’s activities. For example, if a new design method is to be used for the first time, training in that method should be scheduled just prior to commencing the design activity. Record training plans in the software plan.\n\nPlanning to manage risks—The software manager is responsible for performing risk management in accordance with local standards. Record the risk management approach in the software plan. (See Reference 8.)\n\nPlanning to monitor technical performance measures—There are sometimes situations in which a software CI has specific performance requirements (explicitly defined or implicitly determined), such as maximum processor or memory utilization, minimum response time, etc. Technical Performance Measurement (TPM) enables the software team to monitor and fine-tune the product to meet its performance requirements, thus mitigating the risks associated with such requirements. In such cases, the software manager integrates TPM into the software engineering process in accordance with local standards. Record the TPM approach in the software plan.\n\nPlanning for software process improvement activities—Every software project presents an opportunity to study or improve the software process. Process studies may be conducted any time a life-cycle or activity-related method other than those recommended in this guidebook is selected by the software manager. These studies enable the software manager to assess the impact of the new technology on the overall product and process, or gain a more in-depth understanding of regularly used technologies. (See Section 2.2.3.) The software manager documents the planned use of a study in the software plan.\n\nSelecting measures to facilitate monitoring and controlling the project—The software manager defines a set of software management indicators to facilitate monitoring the progress of the project. Table 6–4 lists required software engineering activities and summarizes measures that have proven worthwhile for monitoring those activities on NASA software projects. Record in the software plan the measures to be used, and how they will be collected and analyzed.\n\nActivity requirements continued on next page\nActivity requirements continued\n\n**Primary products.** The primary products from this activity are as follows:\n\n- Training plan\n- Risk management plan\n- TPM plan\n- Process improvement plan\n- Management measurement plan\n\n<table>\n<thead>\n<tr>\n<th>Table 6–4. Required Activities and Related Measures</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Activity</strong></td>\n</tr>\n<tr>\n<td>Software project planning</td>\n</tr>\n<tr>\n<td>Software CI requirements definition and analysis</td>\n</tr>\n<tr>\n<td>Software CI design</td>\n</tr>\n<tr>\n<td>Software CI implementation and testing</td>\n</tr>\n<tr>\n<td>Software CI qualification testing</td>\n</tr>\n<tr>\n<td>Preparing for software delivery</td>\n</tr>\n<tr>\n<td>Software project close-out</td>\n</tr>\n<tr>\n<td>Software product V&V</td>\n</tr>\n<tr>\n<td>Software configuration management</td>\n</tr>\n<tr>\n<td>Software quality assurance</td>\n</tr>\n<tr>\n<td>Milestone reviews</td>\n</tr>\n<tr>\n<td>Software team preparation</td>\n</tr>\n<tr>\n<td>Project monitoring and controlling</td>\n</tr>\n<tr>\n<td>Software process improvement</td>\n</tr>\n<tr>\n<td>System-level considerations</td>\n</tr>\n</tbody>\n</table>\n\n**Notes:**\n\n- Some NASA organizations typically collect managers' total effort regarding project planning and managing the project (as opposed to specific elements within these activities), because they know (quantitatively) that this amount of effort is a small fraction of the total software engineering effort.\n- Typically, only total effort and schedule are collected and analyzed.\n- If applicable\n\n**Recommended process improvement method**\n\n- Process studies (Table 6–5) (Reference 2)\n### Table 6-5. Process Studies\n\n<table>\n<thead>\n<tr>\n<th>Summary Description and Discussion</th>\n<th>A process study is a method by which the software manager can objectively determine the impact of introducing a new technology into the software engineering process. The study consists of identifying the objective of the change (for example, reduce cost of development), identifying the new technology, recording the baseline characteristic to be improved (for example, development cost of like products), and identifying the measures to demonstrate whether the objective has been attained. The project team applies the new technology to its work. The resulting measures are compared with the baseline characteristics, thus quantifying the effect of the new technology on the product or process. The results are recorded and made available for use by others.</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Advantages</td>\n<td>Provides an objective means of assessing a new software technology.</td>\n</tr>\n<tr>\n<td>Disadvantages</td>\n<td>None</td>\n</tr>\n<tr>\n<td>Most appropriate when ...</td>\n<td>A new technology is being used.</td>\n</tr>\n</tbody>\n</table>\n| Key products | • Process study plan \n• Process study report |\n\n**TIPS — Team training**\n\n- Work with your organization’s training committee to determine what training techniques are available and will best meet the software team’s needs.\n- Have local experts train in their specialty areas.\n- Have QA personnel conduct training. They are well versed in your processes and product standards.\n- For training in group-oriented activities (for example, testing, inspections), have the software team go through the training as a group. Include in the group, personnel who are already experienced in the subject; this allows those people to relate the training material specifically to the project.\n\n**TIPS — TPM**\n\nConsider planning to develop prototypes to facilitate actual measurement of certain performance-related aspects of the software product. For example, when performance requirements are levied on a database-intensive software product, plan to develop a simple prototype driver to learn where the performance limits of the database package lie.\n6.4 Reviewing the Software Plan\n\nActivity Requirements\n\nReviewing the Software Plan\n\nObjective. Ensure that stakeholders are aware of, and have an opportunity to review, the software plan.\n\nKey elements, roles, and responsibilities.\n- Review the plan using the locally defined review process.\n- Iterate until stakeholders are satisfied with the estimates and plan.\n- Distribute copies of the plan to stakeholders (that is, to team members, and appropriate team and customer management) and use the plan to run the software project.\n\nPrimary products. The primary product from this activity is as follows:\n- Project’s software plan\n\nTIPS — Management Measures\n\n- There’s always some effort associated with data collection, analysis, and reporting. Collect, analyze, and report only data that are worthwhile to the project, the organization, and NASA.\n- Work with your QA representative and process improvement personnel to determine an appropriate set of measures and data collection approach.\n- Ensure from the start that you know what data will be required at project close-out and put appropriate mechanisms in place to facilitate providing them.\nChapters 3 through 6 discussed how to develop a plan to facilitate running the project. This chapter focuses on the software manager’s activities during the execution of the project. Those activities are shown in the shaded portions of Figure 7-1:\n\n- Using the software plan to guide the project in its engineering efforts\n- Closing out the project.\n\n<table>\n<thead>\n<tr>\n<th>Time</th>\n<th>Develop initial project software plan</th>\n<th>Monitor and control software project</th>\n<th>Close out software project</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>Perform required technical activities (i.e., software CI requirements definition and analysis through qualification testing, including interim deliveries)</td>\n<td>Maintain project software plan and records as necessary</td>\n<td>Deliver final software products</td>\n</tr>\n<tr>\n<td></td>\n<td>Indepenently assure software products and activities (SQA)</td>\n<td>Prepare software team</td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Manage configuration (SCM)</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Participate in milestone reviews</td>\n<td></td>\n<td></td>\n</tr>\n<tr>\n<td></td>\n<td>Validate and verify (V&V) software products</td>\n<td></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n*Figure 7-1. Running the Project*\n7.1 Managing the Project\n\n### Activity Requirements\n\n**Managing the Project**\n\n- **Objective.** Software managers are expected to complete their projects on schedule and within a allowable percentage of the baseline budget. The manager uses an integrated set of management techniques to aid in accomplishing this objective.\n\n- **Key elements, roles, and responsibilities.** Managing the project includes the following key elements:\n - Preparing the software team\n - Monitoring and controlling\n - Communicating with the stakeholders\n - Maintaining the project software plan\n - Keeping records\n\nSubsequent subsections provide details on each of these elements.\n\n- **Primary products.** The primary product from the activity is as follows:\n - Management products (details in following subsections)\n\n---\n\n7.1.1 Preparing the Software Team\n\n### Activity Requirements\n\n**Preparing the Software Team**\n\n- **Objective.** Ensure the software team is prepared for upcoming activities.\n\n- **Key elements, roles, and responsibilities.** The software manager ensures the software team is prepared for upcoming activities by acquiring training as needed and by holding phase orientation meetings.\n\n The software manager ensures delivery of project-specific training based on the training plan recorded in the software plan. The phase orientation meetings ensures that the software team is aware of and understands the products that will be created during each life-cycle phase (or particular major activity), as well as the activities, methods, procedures, product standards, and support tools that will be used to generate the products.\n\n- **Primary products.** The primary product from the activity is as follows:\n - Training records\n7.1.2 Monitoring and Controlling the Project\n\nActivity Requirements\n\nMonitoring and Controlling the Project\n\nObjective. The software manager uses software management indicators to help monitor the status of the project and to initiate corrective action in a timely fashion.\n\nKey elements, roles, and responsibilities. The software manager monitors the project by comparing actual measured values with planned or expected values (that is, those measures identified in Section 6.3). When variations between actual performance and the plan become excessive, the manager initiates appropriate corrective actions. (See Reference 5 for examples.)\n\nManaging Effort, Schedule, and Quality\n\n- Collect actual effort expended on software engineering activities using team members’ time accounting data. Use software product V&V records (certification records specifically) as a reliable, consistent tool to support monitoring product completion.\n- Use software product V&V records as a reliable, consistent tool to support monitoring product quality.\n\nBy monitoring progress, productivity, and quality, the software manager will discover whether or not the plan is effective. Although measurement data alone are not sufficient for gauging the plan’s effectiveness, they can help the manager to perform some assessment.\n\nManaging Risks—Risk management requires that software managers identify, analyze, and plan to mitigate risks. Review and reassess risks regularly. When new risks are identified, analyze them immediately and plan for mitigation. Close out risks that no longer exist.\n\nManaging Critical Technical Performance Measures—Monitor critical technical performance measures in accordance with local standards.\n\nPrimary products. The primary products from this activity are as follows:\n\n- Status records\n- Corrective actions\n\nTIPS\n\n!! Appoint a release leader to coordinate and support the development of a release throughout its implementation, testing, and transition to the client. Coordinating release-specific activities through a single point of contact enables the software team to stay focused on the task at hand; that is, finishing the release.\n7.1.3 Communicating with Stakeholders\n\nActivity Requirements\n\n**Communicating with Stakeholders**\n\nObjective. The effective use of status reports and meetings can facilitate timely communication among the various stakeholders in a software project to ensure that there are no surprises.\n\nKey elements, roles, and responsibilities. The software manager is responsible for communicating with the stakeholders. Table 7–1 lists recommended status reports and meetings and their purposes.\n\nPrimary products. The primary products from this activity are as follows:\n\n- Status reports\n- Meetings\n\n<table>\n<thead>\n<tr>\n<th>Mechanism</th>\n<th>Purpose</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><strong>Status reports</strong></td>\n<td></td>\n</tr>\n<tr>\n<td>Weekly progress reports</td>\n<td>To ensure regular communication of recent activities and outstanding issues</td>\n</tr>\n<tr>\n<td>Monthly status reports</td>\n<td>To ensure regular review and reporting of progress and cost</td>\n</tr>\n<tr>\n<td><strong>Meetings</strong></td>\n<td></td>\n</tr>\n</tbody>\n</table>\n| Periodically with the project team members | To communicate or discuss issues and changes\nTo provide a forum for questions and answers\nTo strengthen team cohesiveness |\n| Periodically with the customer | To communicate or discuss issues and changes\nTo maintain insight into customer's “hot buttons” |\n| With interfacing groups as needed | To communicate or discuss issues and changes |\n\nTIPS—Meetings\n\n- Hold status meetings regularly, not just when there is a problem.\n- Keep lists of action items and review them at each meeting\n- Follow up with meeting minutes to all meeting attendees\nTIPS—Status\n\nPost progress and quality status for all to see. Numerous software project managers regularly post their projects’ progress (planned vs. actuals) and quality (expected vs. observed) status for their teams to see. When (for example) a project is behind schedule, posting the status often encourages the team to catch up or even get ahead of the plan.\n\nTIPS—Product Handovers\n\nAny time a product is handed over from one group to another, internal groups as well as external, hold walkthroughs of the product in which the supplier briefs the consumer. Two-way walkthroughs are even more comprehensive, where the supplier briefly consumer; then consumer briefs supplier as to understanding, often raising questions. Examples of product handovers are shown in Figure 7–2.\n\n<table>\n<thead>\n<tr>\n<th>System requirements allocated to SW CI</th>\n<th>Software CI requirements definition team</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Software CI requirements</td>\n<td>Designers</td>\n</tr>\n<tr>\n<td>Software design</td>\n<td>Implementers</td>\n</tr>\n<tr>\n<td>Tested code components</td>\n<td>SW CI integrators and testers</td>\n</tr>\n<tr>\n<td>Tested software CI</td>\n<td>System integrators and testers</td>\n</tr>\n<tr>\n<td>Tested system</td>\n<td>Customer</td>\n</tr>\n</tbody>\n</table>\n\nFigure 7–2. Product Handovers\n7.1.4 Maintaining the Software Plan\n\nActivity Requirements\n\nMaintaining the Software Plan\n\nObjective. The software plan will be a successful management aid only to the extent that it is followed. Expect the plan to change and evolve as the project continues, so that throughout the development effort it provides the following:\n\n- Documentation of the current project organization (that is, roles and responsibilities)\n- A baseline reference against which to measure and compare actual project performance and activities\n- Detailed clarification of the technical and management approach being used\n\nKey elements, roles, and responsibilities. The software manager is responsible for periodically reviewing and assessing the effectiveness of the software plan. At the end of each phase or build, review and revise if necessary the estimates of project size, effort, and schedule, and update this information in the plan. (Do not, however, delete earlier estimates. They provide a record of the planning process that will be needed for the software project history and show which estimation techniques were successful and should be used again.)\n\nAn effectively maintained software plan documents the current strategy for the software effort. Because it provides a uniform characterization of the project, it can be invaluable if changes occur in team leadership. Ensure that the plan is realistic, otherwise continual modifications will be required to reflect actual decisions or experiences. While the plan should be revised as needed to reflect the current engineering environment, particularly regarding schedules and organizational relationships, significant revisions should not be considered routine document maintenance. For example, major shifts in technical approach or methodologies should occur only if absolutely necessary.\n\nWhen significant changes are determined to be necessary, the plan should be updated and those updates should be communicated to all personnel who hold copies of the plan. Copies of the plan should be provided to all personnel affected by the change.\n\nPrimary products. The primary product from this activity is as follows:\n\n- Up-to-date software plan\n7.1.5 Keeping Project Records\n\nActivity Requirements\n\nKeeping Project Records\n\nObjective. Basic records are kept to facilitate tracking critical issues, to provide valuable historical information for others to learn from, and to meet software requirements.\n\nKey elements, roles, and responsibilities. The software manager is responsible for keeping the following basic project records:\n\nAction items—record and track action items\n- From meetings with the client\n- From milestone reviews\n- From meetings with upper management\n- From deficiencies found by audits\n- Regarding outstanding requirements and design issues and questions\n\nSoftware project history—At the end of each life-cycle phase (at a minimum) prepare a brief summary of the phase. Record such topics as what went well, what didn’t, what surprises sprang up, what should have been done differently, etc. This will form the foundation for the final software project history report.\n\nPrimary products. The primary product from this activity is as follows:\n- Project records\n\nTIPS\n\n- Consider maintaining a daily or weekly diary that includes (among other things):\n - Actual completion dates\n - Personnel changes\n - When significant changes or problems were first discovered or discussed\n - When significant breakthroughs or brainstorms occurred\n- Consider recording end-of-life-cycle phase summaries right in the software plan. This is a simple means of almost automatically producing the software history, right from the start.\n7.2 Closing Out the Project\n\nActivity Requirements\n\nClosing Out the Project\n\nObjective. Finalize historical records of the software project for use by other software projects, and process groups within the organization.\n\nKey elements, roles, and responsibilities. The software manager prepares a software project history that includes all applicable items in the organization’s software project history documentation standard, and software project close-out data that characterizes both the final product generated and the process used to accomplish the work. Forward a copy of the software project history and the software close-out data to the organization responsible for including it in the PAL.\n\nPrimary products. The primary products from this activity are as follows:\n\n- Software project history (including software project lessons learned and recommendations for improvement)\n- Software project close-out data\n\nTIPS—Preparing the Project Software History Report\n\n- Consider involving interested software team members in completing the project’s software history report.\n- Also consider involving the QA representative and a member of a process group. They can help analyze and package the results of any significant technology study that was conducted on the project.\nTIPS—Sharing Lessons Learned\n\nUpon completion of every software project, there’s a wealth of information that is vital to the rest of the organization and needs to be shared. The following is a list of several mechanisms that can facilitate sharing that information. Consider using more than one of these mechanisms to ensure a broad dissemination of this invaluable information.\n\n- Lunch time seminars\n- Managers’ and staff meetings\n- Newsletters\nAppendix A. Glossary\n\nAcceptance. An action by the customer (or an authorized representative) by which the customer assumes ownership of software products as partial or complete fulfillment of software requirements.\n\nActivity. A unit of work that has well-defined entry and exit criteria. Activities can usually be broken into discrete steps.\n\nAdapted unit. An existing unit that changes substantially (more than 25 percent of its content is changed, added, or deleted). Its origin is usually external to the project. (Contrast with new unit, converted unit, transported unit.)\n\nArchitecture. The organizational structure of a system or software CI, identifying its components, the component interfaces, and a concept of execution among the components.\n\nBuild. A version of software that meets a specified subset of the requirements that the completed software will meet. (See also release.)\n\nCertification. Written confirmation that a work product has been evaluated (for example, inspected or tested) and any defects found by that evaluation process have been satisfactorily resolved.\n\nConfiguration item (CI). System component (for example, hardware CI or software CI) that is developed or purchased, controlled, accepted, and maintained separately from other system components. In practice, it is a component that is convenient and sensible to document and control as an entity. (See software configuration item.)\n\nConverted unit. Existing unit that changes slightly (up to 25 percent of its content is changed, added, or deleted). Its origin is usually external to the project. (Contrast with new unit, adapted unit, transported unit.)\n\nCOTS (or GOTS) software. Commercial (or government), off-the-shelf software. COTS and GOTS software includes (1) unique components that must be delivered with the product to execute the operational software and (2) development tools that must be delivered with the product to support maintenance of the software.\n\nCustomer. The organization that procures software products for itself or another organization.\n\nCycle time. Elapsed calendar time (not effort) required to complete a given piece of work. For software efforts, cycle time usually refers to either (1) the full product engineering period (from initial receipt of product requirements through acceptance by the customer of the fully functional delivered product) or (2) a release cycle (from agreement on the requirements for the release through acceptance by the customer of the delivered product). The latter case, the release cycle, can pertain to new development releases as well as maintenance and enhancement releases. (See also software life cycle.)\n\nDesign. Those characteristics of a system or software CI that are selected by the software team in response to the requirements (see requirements). Some will match the requirements; others will\nbe elaborations of requirements, such as definitions of all error messages in response to a requirement to display error messages; still others will be implementation related, such as decisions about what software units and logic to use to satisfy the requirements.\n\n**Development.** Production of a new product that leads to delivery of all initially planned functional capability. The new product may be built from newly created components, reused components (with or without adaptations), GOTS components, and COTS components. (Contrast with enhancement, maintenance; see also software engineering.)\n\n**Documentation.** A collection of data, regardless of the medium (or media) on which it is recorded, that generally has permanence and can be read by humans or machines. The significance of this definition is that documents do not necessarily have to be separately bound entities; they may comprise data in several media (for example, plans, CASE tools, databases).\n\n**Enhancement.** A major addition or change in the functionality of an operational system; often includes many of the same activities as new development. (Contrast with new development, maintenance; see also software engineering.)\n\n**Firmware.** The combination of a hardware device, computer instructions, and computer data that reside as read-only software on the hardware device.\n\n**GOTS software.** (See COTS/GOTS software.)\n\n**Inspection.** A process whereby products are reviewed for correctness, completeness, quality, and compliance with requirements and standards. The process is carried out by one or more peers of the product’s developer. (Contrast with walkthrough.)\n\n**Joint application design (JAD).** A facilitated workshop technique that brings together principal stakeholders to solve a well-defined problem to produce a well-defined product or set of products.\n\n**Life cycle.** (See software life cycle.)\n\n**Life-cycle model.** A framework on which to map activities, methods, standards, procedures, tools, products, and services (for example, waterfall, spiral).\n\n**Life-cycle phase.** A division of the software effort into non-overlapping time periods. Life-cycle phases are important reference points for the software manager. Multiple activities may be performed in a life-cycle phase; an activity may span multiple phases. (Contrast with activity.)\n\n**Maintenance.** Implementation of problem fixes and minor enhancements to an operational product. (Contrast with new development, enhancement; see also software engineering.)\n\n**Method.** A technique or approach, possibly supported by procedures and standards, that establishes a way of performing activities and arriving at a desired result.\n\n**Methodology.** “A collection of methods, procedures, and standards that defines an integrated synthesis of engineering approaches to the development of a product.” (Reference 22)\n\n**Milestone review.** A process or meeting involving representatives of both the customer and the software team, during which project status, software products, and project issues are examined and discussed.\n\n**Module.** A cohesive group of software units that performs a software function.\nNew development. (See development.)\n\nNew technology. A technology that has not yet been proven to be effective in practice in a particular NASA application area or domain. It may have been proven elsewhere, however. (See also technology.)\n\nNon-developed item (NDI). A component that is not newly created by the software team. This includes reused components, COTS and GOTS components, and components developed by other NASA groups or contractor personnel.\n\nOrganization. “A unit within [NASA] within which many projects are managed as a whole. All projects within an organization share a common top-level manager and common policies.” (Reference 22)\n\nPhase. (See life-cycle phase.)\n\nPolicy. “A guiding principle, typically established by senior management, which is adopted by an organization or project to influence and determine decisions.” (Reference 22) (Contrast with procedure, standard.)\n\nProcedure. A written description of the roles, responsibilities, and steps required for performing an activity or a subset of an activity. (Contrast with policy, standard.)\n\nProcess. “A sequence of steps performed for a given purpose; for example, the software engineering process.” (Reference 9)\n\nProcess asset library (PAL). A NASA library, including a life-cycle methodology description, standards and procedures, guidebooks and handbooks, style guides, software profiles, key lessons, study results, tailored processes, examples of acceptable products, etc.\n\nProduct. (See software product.)\n\nProject. (See software project.)\n\nProject process. A tailored version of the organization’s standard process, defining and integrating specific life-cycle models, activities, methods, procedures, standards, and tools used to accomplish delivery of the project’s required products and services. It is defined in the\n\nPrototype. An early experimental model of a system, system component, or system function that contains enough capabilities for it to be used to establish or refine requirements, or to validate design concepts.\n\nQualification testing. Testing performed to verify and demonstrate (often to the customer) that a software CI or a system meets its specified requirements.\n\nRecord. To record information means to set down in a manner that can be retrieved and viewed. The result may take many forms, including but not limited to hand-written notes, hard-copy or electronic documents, and data recorded in CASE and project management tools. Information to be delivered to the customer must be in the form, format, and medium agreed to with the customer. For information not to be delivered to the customer, the software manager selects the appropriate form, format, and medium.\n\nRelease. A build that is delivered to the customer. (See build.)\nRequirement. A characteristic that a system or software CI must possess in order to be acceptable to the customer.\n\nReused code. Code that has undergone no more than 25 percent change; that is, converted code and transported code. (See converted unit, transported unit.)\n\nSoftware configuration item (CI). An aggregation of software that satisfies an end use function and is designated for separate configuration management by the customer or the maintenance team. Software CIs are selected on the basis of tradeoffs among software function, size, host or target computers, developer, support concept, plans for reuse, criticality, interface considerations, need to be separately documented and controlled, and other factors.\n\nSoftware engineering. A set of activities that results in software products. Software engineering includes new development, modification, reuse, reengineering, maintenance, or any other activities that result in software products.\n\nSoftware engineering environment. The facilities, hardware, software, firmware, procedures, and documentation needed to perform software engineering. Elements may include but are not limited to CASE tools, compilers, assemblers, linkers, loaders, operating systems, debuggers, simulators, emulators, documentation tools, and database management systems.\n\nSoftware engineering process. An organized set of activities performed to translate user needs into software products.\n\nSoftware life cycle. “The period of time that begins when a software product is conceived and ends when the software is no longer available for use.” (Reference 9) A life cycle is typically divided into life-cycle phases. (See life-cycle phase.)\n\nSoftware process. (See software engineering process.)\n\nSoftware product. Software or associated information created, modified, or incorporated to satisfy the software requirements. Examples include plans, requirements, design, code, databases, test information, and manuals.\n\nSoftware product evaluation. Activities performed by the software team to ensure that in-process and final software products meet criteria established for those products. (Contrast with software quality assurance.)\n\nSoftware project. An undertaking requiring a concerted effort, which is focused on developing or maintaining a specific software product. Typically a software project has its own funding, cost accounting, and delivery schedule. That is, the project is the work to be done and the personnel assigned to perform the work; it is not the same as the product (for example, system) that they are to produce.\n\nSoftware quality assurance (SQA). Activities performed by independent QA personnel to (1) ensure that each activity described in the software plan is performed in accordance with the software plan, and (2) ensure that each software product required by the organization or by software requirements exists and has undergone software product evaluations, testing, and corrective action as required. (Contrast with software product evaluation.)\n\nSoftware system. A system consisting solely of software and possibly the computer equipment on which the software operates.\nSoftware team. The group that engineers software products (including new development, modification, reuse, reengineering, maintenance, or any other activity that results in software products).\n\nSoftware test environment. The facilities, hardware, software, firmware, procedures, and documentation needed to perform qualification, and possibly other, testing of software. Elements may include but are not limited to simulators, code analyzers, test plan generators, and path analyzers, and may also include elements used in the software engineering environment.\n\nSoftware transition. The set of activities that enables responsibility for software engineering to pass from one organization, usually the organization that performs initial software development, to another, usually the organization that will perform sustaining engineering.\n\nSoftware unit. Smallest physical element of software processed by source code translators, compilers, and assemblers.\n\nStandard. Written criteria used to develop and evaluate a product or to provide and evaluate a service. (Contrast with policy, procedure.)\n\nSustaining engineering. Maintenance and enhancement of an operational product. (See maintenance, enhancement.)\n\nSystem. Operational entity composed of a set of interrelated and cohesive configuration items (CIs). (See configuration item (CI).)\n\nTechnology change management. “... [I]dentifying, selecting, and evaluating new technologies, and incorporating effective technologies into the organization. The objective is to improve software quality, increase productivity, and decrease cycle time for product engineering.” (Reference 22)\n\nTechnology infusion. (Used synonymously with technology transfer; see technology transfer.)\n\nTechnology management. (See technology change management.)\n\nTechnology transfer. The successful importing or exporting of technology from lab to practice or from practice to practice.\n\nTechnology utilization. The application and integration of appropriate technologies in software efforts.\n\nTimebox. A subdivision of a release created to achieve a unit of production that is manageable in size, complexity, staffing, and duration. It is a planning construct that controls functionality delivered by fixing resources and time.\n\nTransported unit. Existing unit that is used verbatim (except for possible changes to the development history for traceability). Its origin is usually external to the project. (Contrast with new unit, adapted unit, converted unit.)\n\nUnit. (See software unit.)\n\nValidation. “The process of evaluating software during or at the end of the software development process to determine whether it satisfies specified requirements.” (Reference 9) (Contrast with verification.)\n**Verification.** “The process of evaluating software to determine whether the products of a given development phase [or activity] satisfy the conditions imposed at the start of that phase [or activity].” (Reference 9) (Contrast with *validation*.)\n\n**Walkthrough.** Detailed technical presentation of a limited aspect or portion of a product. These presentations are usually made by the product’s developer. (Contrast with *inspection.*)\nAppendix B. Building for Reuse\n\nReuse can apply to people, code, processes, requirements, and design, as well as to plans, standards, and test scripts. Although a recent study of NASA software (Reference 1) indicated that most reuse at the Agency focuses solely on code, reusing any of these resources in the development of a new system is appropriate when the result will be improved reliability, productivity, and maintainability without a negative impact on performance or requirements satisfaction. Planning for reuse maximizes its benefits; therefore, design software projects for reuse from the outset. During the requirements definition and analysis and design phases, for example, developers need to identify potentially reusable architectures, designs, code, and approaches. To facilitate this process, provide developers with the structure and tools that will assist them in finding and reusing existing components and architectures rather than developing new software from scratch. Several activities can be performed throughout the life cycle to enable reuse:\n\n- Perform **domain analysis** by examining the application domain to identify common requirements and functions. The result is a standard, general architecture or model that incorporates the common functions of a specific applications area and can be tailored to accommodate differences among individual projects.\n- Domain analysis enables **requirements generalization**, which involves preparing requirements and specifications so that they cover a selected family of projects or missions.\n- During the design phase, explicitly **design for reuse** by providing modularity, standard interfaces, and parameterization.\n- Place reusable source code in a **reuse library**, along with the associated requirements, specifications, design documentation, and test data. Such a library should also contain a search facility that enables varied access to the software (for example, by keyword or by name).\n- A final activity that enables reuse on future projects involves the application of **reuse preservation** techniques during the maintenance and operations phase. The maintenance team should avoid making quick fixes, which can negatively affect the reusability of the system. Rather, they should apply many of the same design practices that promote reuse during software development. Alternatively, a separate maintenance team might be established to maintain only the software in a reusable software library. The team would notify projects that incorporate software from the library of any changes to that software.\n\nSystems employing a high percentage of reused software typically still undergo each phase of the full development life cycle, but certain reviews and documents may be consolidated and phase schedules collapsed or overlapped (see Figure Appendix B. -1). Reusing design, documentation, and code written for a previous project (and perhaps adapting it to some degree for use in the system to be developed) requires less effort than creating entirely new products.\nFigure Appendix B. -1. High-Reuse Life-Cycle Model\nAppendix C. COTS, GOTS, Reused, and Other NDI Software Products\n\nThis appendix provides guidance to the software manager for satisfying the requirements of this guidebook when applied to incorporating COTS, GOTS, reused, and other NDI products.\n\nAppendix C.1 COTS Software Products\n\nUsing COTS products involves cultural implications. For example, in making a decision to incorporate COTS software, stakeholders must first be willing to accept the capabilities it provides. Although it is possible to negotiate with a vendor to obtain and modify the source code, in so doing vendor support will be lost, and the system will be inconsistent with future product releases.\n\nWhen considering the use of a COTS product, conduct the following activities during the activities indicated:\n\n- Prototype during requirements definition and analysis to evaluate the product’s capabilities and performance. Whereas prototyping typically is conducted to clarify requirements or define a user interface, here it is performed to assess whether the product meets already defined functionality and performance requirements. Prototype to analyze the performance of the product, to assess its capabilities in relation to the requirements, and to evaluate its ease of use. Conduct this activity as early as possible in the life cycle, because the resulting decision on whether to use a COTS product may affect the overall system architecture. Defining the system architecture thus becomes an iterative step that evolves based on the results of the prototyping efforts, because only a certain requirement or set of requirements may be satisfied by COTS capabilities.\n\n- As soon as prototyping results indicate that use of a COTS product is appropriate, plan for its interfaces to other COTS products or to the rest of the system. The input/output requirements of the COTS product must be carefully and completely defined and understood, so that its interfaces to other components, custom as well as COTS, can be created correctly. At this point, assess the following:\n - The effort required to develop the interface software versus the effort required to custom develop all the code\n - The maintainability of the COTS software\n - The reliability of the COTS software\n - The quality and reliability of vendor support (which will be crucial to successful implementation)\nDuring design, address the connections to COTS products in the same way as other system interfaces. Because no design products exist for COTS software, devise artifacts that provide the traceability from COTS products to requirements.\n\nDuring implementation, no code will be written for the COTS products themselves; however, testing becomes an issue because a COTS product cannot be tested at the unit level (that is, as in unit testing of custom software). The test plan must thus focus on the interfaces to COTS products. Apply additional rigor in analyzing the test output. Do not assume that less testing effort will be required for a COTS product; rather, the effort typically applied at the unit and module levels will simply be applied to testing at a higher level for COTS interfaces. If test results indicate that a COTS portion of the system is not performing as required, obtain vendor support in troubleshooting and correcting the problem.\n\nThroughout the development cycle, reassess the selection of a COTS product when requirements changes affect a part of the architecture that is satisfied by that product.\n\nContinually stay abreast of and reassess new versions of COTS products. Conduct additional prototyping to evaluate their use and enable the project to take advantage of new capabilities or to recognize possible changes in system architecture. However, at some point in the life cycle, it will be necessary to finalize the version selection and proceed with development, regardless of new capabilities that may become available. If using a multi-release approach, allow flexibility in the design to facilitate the upgrade of COTS products assigned to later releases.\n\nDuring operations, weigh the need for capabilities provided by new versions of the COTS software against a possible lack of vendor support for older versions. For operational systems with multi-site installations, apply rigorous configuration management to ensure version control.\n\nManaging a project that comprises predominantly COTS products is similar to managing a custom-development project. All of the same good management practices apply here as well. However, package vendors are a source of risk that needs special attention. When a project selects a package to be part of a system, it is buying a long-term relationship with a vendor. Understanding a vendor's financial stability, track record, and long-term strategy can be as important as understanding the vendor’s product. Not only must the project develop a partnership with its vendors, but it must also develop a partnership with the contracting and procurement side of its own organization. Software project managers must acquire a level of business understanding well beyond that needed in conventional development to successfully manage the project.\n\nThis life-cycle concept requires the formation of a well-integrated team consisting of end-users, domain experts, software engineers, independent testers, a system administrator, and a procurement official, all coordinated by a project leader. The team roles must remain intact for the entire system life cycle, and team members must be empowered to make decisions as to which system requirements are critical. Many of the traditional roles change slightly or require different skills. In addition, the project team includes two new roles, the system administrator and a procurement official, who play significant roles in comparison to the minimal support needed in these areas on traditional software development projects. A capable and interested procurement official and systems administrator will be great assets to the project. If possible, arrangements should be made to have a single procurement official and a system administrator.\nassigned to the project. Every effort should be made to make them aware of project needs and to welcome them as members of the team.\n\nThe primary project roles are as follows:\n\nEnd-User. The end-users are the people who will be using the system operationally. They have a clear understanding of the requirements and the operational environment and are empowered to negotiate requirements changes and represent the end-user organization.\n\nDomain expert. Domain experts have extensive experience in the problem domain and are aware of existing packages that are available within the domain. They have experience with, or are at least aware of, other package-based systems within the domain from which architectures can be reused.\n\nSoftware engineer. Software engineers or developers are responsible for developing glueware and integrating the packages. They are responsible for engineering a solution that meets the customer’s and end-users’ quality expectations. It is best if the software engineers have some experience with COTS integration or have specific experience with the packages being used.\n\nIndependent tester. Independent testers are responsible for verifying that the system meets its requirements. Experience with the application domain, incremental testing, and black-box testing is helpful.\n\nProcurement officer. Procurement officers are responsible for obtaining demonstration copies for evaluation; purchasing selected products and negotiating for extensions of demonstration copies until official receipt of product; monitoring and extending license expiration dates. They are responsible for keeping the project point-of-contact informed of expected product arrival dates and the terms of the contracts.\n\nSystem administrator. System administrators are responsible for installing COTS products as they are received and setting up accounts as they are needed. They can also help troubleshoot problems with hardware/package compatibility. It is critical that a system administrator be available to provide services immediately upon request, so it is best if one is dedicated to the project.\n\nAppendix C. .2 Evaluating COTS, GOTS, Reused, and Other NDI Software Products\n\nThe software manager specifies in the software plan the criteria for evaluating COTS, GOTS, reused, and other NDI software products for use in fulfilling software requirements. General criteria are the software product’s ability to meet specified requirements and cost-effectiveness over the life of the system. Examples of specific criteria include but are not limited to the following:\n\n- Ability to provide required capabilities and meet required constraints\n- Ability to provide required safety, security, and privacy\n- Reliability and maturity, as evidenced by an established track record\n- Testability\n- Interoperability with other system and system-external elements\nFielding issues, including:\n- Restrictions on copying and distributing the software or documentation\n- License or other fees applicable to each copy\n\nMaintainability\n- Likelihood the software product will need to be changed\n- Feasibility of accomplishing that change\n- Availability and quality of documentation and source files\n- Likelihood that the supplier will continue to support the current version\n- Impact on the system if the current version is not supported\n- The customer’s data rights to the software product\n- Warranties available\n\nShort- and long-term cost impacts of using the software product\n\nTechnical, cost, and schedule risks and tradeoffs in using the software product\n\nAppendix C. .3 Guidelines for Performing Required Activities Involving COTS, GOTS, Reused, and Other NDI Software Products\n\nThe following guidelines are provided to help interpret and satisfy the requirements to perform life-cycle activities:\n\n- Any software product required by this document may be a COTS, GOTS, reused, or other NDI software product as long as it meets the criteria established in the software plan. The software product may be used as is or modified.\n\n- When COTS, GOTS, reused, or other NDI software has been selected to be incorporated into the delivered software product, some requirements in this document must have special interpretation. Table Appendix C. –1 provides this interpretation. Key issues are whether the software will be modified, whether the unmodified software constitutes an entire software CI or only one or more software units, and whether the unmodified software has a positive performance record. The table is presented in a conditional manner: If an activity in the left column is required for a given type of software, the table tells how to interpret the activity for COTS, GOTS, reused, or other NDI software of that type.\nTable Appendix C. –1. Guidelines for Using COTS, GOTS, Reused, and Other NDI Software Products\n\n(1 of 2)\n\n<table>\n<thead>\n<tr>\n<th>Required Activity</th>\n<th>Interpretation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Software project planning</td>\n<td>Include the activities in this table in project plans.</td>\n</tr>\n<tr>\n<td>No requirement: software CI is already tested and proven.</td>\n<td></td>\n</tr>\n<tr>\n<td>Specify the project-specific requirements the software CI must meet; verify through records or retest that the software CI can meet them.</td>\n<td></td>\n</tr>\n<tr>\n<td>Include the component’s capabilities and characteristics in specifying the requirements for the software CI of which it is a part.</td>\n<td></td>\n</tr>\n<tr>\n<td>Software CI-wide design</td>\n<td>Consider the component’s capabilities and characteristics in designing software CI behavior and making other software CI-wide design decisions.</td>\n</tr>\n<tr>\n<td>No requirement: the software CI-wide design decisions have already been made.</td>\n<td></td>\n</tr>\n<tr>\n<td>Software CI architectural design</td>\n<td>Include the component in the software CI architecture and allocate software CI requirements to it.</td>\n</tr>\n<tr>\n<td>No requirement: the software CI’s architecture is already defined.</td>\n<td></td>\n</tr>\n<tr>\n<td>Software CI detailed design</td>\n<td>No requirement: the component is already designed.</td>\n</tr>\n<tr>\n<td>No requirement: the component is already designed.</td>\n<td></td>\n</tr>\n<tr>\n<td>Modify the component’s design as needed.</td>\n<td></td>\n</tr>\n<tr>\n<td>Software implementation</td>\n<td>Modify the software for the component.</td>\n</tr>\n<tr>\n<td>No requirement: the software for the software CI’s components is already implemented.</td>\n<td></td>\n</tr>\n<tr>\n<td>No requirement: the software for the component is already implemented.</td>\n<td></td>\n</tr>\n<tr>\n<td>Unit testing</td>\n<td>Perform this testing.</td>\n</tr>\n<tr>\n<td>No requirement: the software CI’s units are already tested. Perform selectively if in question and units are accessible.</td>\n<td></td>\n</tr>\n<tr>\n<td>No requirement: the unit is already tested.</td>\n<td></td>\n</tr>\n<tr>\n<td>Integration and testing</td>\n<td>Perform this testing. Perform except where integration is already tested or proven.</td>\n</tr>\n<tr>\n<td>No requirement: the software CI’s components are already integrated. Perform selectively if in question and components are accessible.</td>\n<td></td>\n</tr>\n<tr>\n<td>Software CI qualification testing</td>\n<td>Include the component in software CI qualification testing.</td>\n</tr>\n<tr>\n<td>No requirement: software CI is already tested and proven. Perform this testing.</td>\n<td></td>\n</tr>\n</tbody>\n</table>\nTable Appendix C.-1. Guidelines for Using COTS, GOTS, Reused, and Other NDI Software Products\n\n(2 of 2)\n\n<table>\n<thead>\n<tr>\n<th>Required Activity</th>\n<th>Interpretation</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Preparation for Software Delivery</td>\n<td>Include the software for the software CI or component in the executable software; prepare source files for the software CI or component, if available; include version descriptions; handle any license issues; prepare or provide as-built design descriptions for software whose design is known; cover use of the software CI or component, as appropriate, through existing, new, or revised user or operator manuals; install the software CI or component at the support site; demonstrate regenerability if source is available; include the training offered.</td>\n</tr>\n<tr>\n<td>Software project close-out</td>\n<td>Apply to activities performed and software products prepared, modified, or used in incorporating this software.</td>\n</tr>\n<tr>\n<td>Software product V&V</td>\n<td>Apply to software products prepared or modified in incorporating this software; for software products used unchanged, apply unless a positive performance record or evidence of past evaluations indicates that such an V&V would be duplicative.</td>\n</tr>\n<tr>\n<td>Software configuration management</td>\n<td>Apply to all software products prepared, modified, or used in incorporating this software.</td>\n</tr>\n<tr>\n<td>Software quality assurance</td>\n<td>Apply to all activities performed and all software products prepared, modified, or used in incorporating this software.</td>\n</tr>\n<tr>\n<td>Milestone reviews</td>\n<td>Cover the software products prepared or modified in incorporating this software; explicitly discuss COTS, GOTS, reused, and other NDI products.</td>\n</tr>\n<tr>\n<td>Software process improvement</td>\n<td>Apply to all activities performed in engineering this software.</td>\n</tr>\n<tr>\n<td>System requirements analysis</td>\n<td>Consider software’s capabilities in defining the system and operations concept and system requirements.</td>\n</tr>\n<tr>\n<td>System-wide design</td>\n<td>Consider the software’s capabilities and characteristics in designing system behavior and in making other system-wide design decisions.</td>\n</tr>\n<tr>\n<td>System architectural design</td>\n<td>Include the software CI in the system architecture; allocate system requirements to it. Consider the component’s capabilities and characteristics in designating software CIs and allocating system requirements to them.</td>\n</tr>\n<tr>\n<td>Software CI and hardware CI integration and testing</td>\n<td>Perform, except where integration is already tested or proven. Include the software CI in software CI and hardware CI integration and testing. Include the component in software CI and hardware CI integration and testing.</td>\n</tr>\n<tr>\n<td>System qualification testing</td>\n<td>Include the software CI in system qualification testing. Include the component in system qualification testing.</td>\n</tr>\n</tbody>\n</table>\nAppendix D. System-Level Considerations\n\nWhen the software CI is part of a larger hardware-software system for which the organization has system-level responsibilities, a number of additional considerations must be taken into account. In the following paragraphs regarding system-level activities, if the software covered by this document is part of a hardware-software system for which this document covers only the software portion, participate means take part in, as described in the software plan. If the software (and the computers on which it executes) is considered to constitute a system, participate means be responsible for.\n\nAppendix D. .1 System Requirements Analysis\n\nThe software requirements analysts participate in system requirements analysis in accordance with the requirements discussed in the subsections that follow.\n\nAnalysis of User Input\n\nThe software requirements analysts participate in analyzing user input provided by the customer to gain an understanding of user needs. This input may take the form of need statements, surveys, problem reports and change requests, feedback on prototypes, interviews, or other user input or feedback. This input is used to formulate the system and operations concept and the system requirements.\n\nSystem and Operations Concept\n\nThe software requirements analysts participate in defining and recording the operational concept for the system. The result includes all applicable items in the system and operations concept documentation standard, including the preparation of any required operational scenarios.\n\nSystem Requirements\n\nThe software requirements analysts participate in defining and recording the requirements to be met by the system and the methods to be used to ensure that each requirement is met. The result includes all applicable items in the system requirements specification (SRS) documentation standard.\n\nIf a system consists of subsystems (or CIs), the activity in this subsection is intended to be performed iteratively with the system design activities to define system requirements, design the system and identify its subsystems, define the requirements for and interfaces among those subsystems, design the subsystems, identify their components, and so on.\n\nAppendix D. .2 System Design\n\nThe software requirements analysts and software design architects participate in system design in accordance with the requirements discussed in the subsections that follow.\nSystem-Wide Design Decisions\n\nThe software requirements analysts and software design architects participate in defining and recording system-wide design decisions (that is, decisions about the system’s behavioral design and other decisions that affect the selection and design of system components). The result includes all applicable items in the system-wide design section of the system design specification (SDS) documentation standard.\n\nDesign decisions remain at the discretion of the software requirements analysts and software design architects unless formally converted to requirements. The software team is responsible for fulfilling all requirements and demonstrating this fulfillment through qualification testing. Design decisions act as software team-internal “requirements,” to be implemented, imposed on contractors (if applicable), and confirmed by software team-internal testing; but their fulfillment need not be demonstrated to the customer.\n\nSystem Architectural Design\n\nThe software requirements analysts and software design architects participate in defining and recording the architectural design of the system (identifying the components of the system, their interfaces, and a concept of execution among them) and the traceability between the system components and system requirements. The result includes all applicable items in the architectural design and traceability sections of the SDS documentation standard.\n\nAppendix D. .3 Software CI and Hardware CI Integration and Testing\n\nSoftware CI and hardware CI integration and testing means integrating software CIs with interfacing hardware CIs and software CIs, testing the resulting groupings to determine whether they work together as intended, and continuing this process until all software CIs and hardware CIs in the system are integrated and tested. The software qualification testers participate in developing and recording test plans (in terms of inputs, expected results, and V&V criteria), test procedures, and test data for conducting software CI and hardware CI integration and testing. The test plans cover all aspects of the system-wide and system architectural design. The software qualification testers participate in software CI and hardware CI integration and testing in accordance with the software CI and hardware CI integration test plans and procedures. The software team participates in analyzing the results of software CI and hardware CI integration and testing. Software-related analysis and test results are recorded in appropriate product V&V records files. The software team makes necessary revisions to the software, participates in retesting, and updates other software products as needed, based on the results of software CI and hardware CI integration and testing.\n\nAppendix D. .4 System Qualification Testing\n\nSystem qualification testing is performed to demonstrate (often to the customer) that system requirements have been met. It covers the SRS. This testing contrasts with software team-internal system testing, performed as the final stage of software CI and hardware CI integration and testing.\nThe persons responsible for fulfilling the requirements in this section are not the persons who performed detailed design or implementation of software in the system, although those persons may participate, for example, by contributing test plans that rely on knowledge of the system’s internal implementation.\n\nThe software qualification testers participate in developing and recording the test preparations, test plans, and test procedures to be used for system qualification testing and the traceability between the test plans and the system requirements. For software systems, the results include all applicable items in the software CI qualification test plan documentation standard. The software qualification testers participate in preparing the test data needed to carry out the test plans and in providing the customer advance notice of the time and location of system qualification testing. They participate in system qualification testing in accordance with the system test plans and procedures. The software team participates in analyzing and recording the results of system qualification testing. For software systems, the result includes all applicable items in the software CI qualification test report documentation standard. The software team makes necessary revisions to the software, provides the customer advance notice of retesting, participates in retesting, and updates other software products as needed, based on the results of system qualification testing.\n## Abbreviations and Acronyms\n\n<table>\n<thead>\n<tr>\n<th>Abbreviation</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>AT</td>\n<td>acceptance test or testing</td>\n</tr>\n<tr>\n<td>ATRR</td>\n<td>acceptance test readiness review</td>\n</tr>\n<tr>\n<td>BDR</td>\n<td>build design review</td>\n</tr>\n<tr>\n<td>BQT</td>\n<td>build qualification testing</td>\n</tr>\n<tr>\n<td>CASE</td>\n<td>computer-aided software engineering</td>\n</tr>\n<tr>\n<td>CDR</td>\n<td>critical design review</td>\n</tr>\n<tr>\n<td>CI</td>\n<td>configuration item</td>\n</tr>\n<tr>\n<td>CM</td>\n<td>configuration management</td>\n</tr>\n<tr>\n<td>COCOMO</td>\n<td>Constructive Cost Model</td>\n</tr>\n<tr>\n<td>COTS</td>\n<td>commercial-off-the-shelf</td>\n</tr>\n<tr>\n<td>CCB</td>\n<td>configuration control board</td>\n</tr>\n<tr>\n<td>DFD</td>\n<td>data flow diagram</td>\n</tr>\n<tr>\n<td>DR</td>\n<td>discrepancy report</td>\n</tr>\n<tr>\n<td>FCA</td>\n<td>functional configuration audit</td>\n</tr>\n<tr>\n<td>FQT</td>\n<td>formal qualification testing</td>\n</tr>\n<tr>\n<td>GOTS</td>\n<td>government-off-the-shelf</td>\n</tr>\n<tr>\n<td>GSFC</td>\n<td>Goddard Space Flight Center</td>\n</tr>\n<tr>\n<td>HQ</td>\n<td>headquarters</td>\n</tr>\n<tr>\n<td>IDR</td>\n<td>internal DR</td>\n</tr>\n<tr>\n<td>IRM</td>\n<td>Information Resources Management</td>\n</tr>\n<tr>\n<td>IV&V</td>\n<td>independent validation and verification</td>\n</tr>\n<tr>\n<td>JAD</td>\n<td>joint application development</td>\n</tr>\n<tr>\n<td>JPL</td>\n<td>Jet Propulsion Laboratory</td>\n</tr>\n<tr>\n<td>MSFC</td>\n<td>Marshall Space Flight Center</td>\n</tr>\n<tr>\n<td>NASA</td>\n<td>National Aeronautics and Space Administration</td>\n</tr>\n<tr>\n<td>NDI</td>\n<td>non-developed item</td>\n</tr>\n<tr>\n<td>NMI</td>\n<td>NASA Management Instruction</td>\n</tr>\n<tr>\n<td>O&M</td>\n<td>operations and maintenance</td>\n</tr>\n<tr>\n<td>ORR</td>\n<td>operational readiness review</td>\n</tr>\n<tr>\n<td>Abbreviation</td>\n<td>Description</td>\n</tr>\n<tr>\n<td>--------------</td>\n<td>-----------------------------------------------------------</td>\n</tr>\n<tr>\n<td>OSMA</td>\n<td>Office of Safety and Mission Assurance</td>\n</tr>\n<tr>\n<td>PAL</td>\n<td>process asset library</td>\n</tr>\n<tr>\n<td>PCA</td>\n<td>physical configuration audit</td>\n</tr>\n<tr>\n<td>PDR</td>\n<td>preliminary design review</td>\n</tr>\n<tr>\n<td>QA</td>\n<td>quality assurance</td>\n</tr>\n<tr>\n<td>QTRR</td>\n<td>qualification test readiness review</td>\n</tr>\n<tr>\n<td>RCR</td>\n<td>release contents review</td>\n</tr>\n<tr>\n<td>RDR</td>\n<td>release design review</td>\n</tr>\n<tr>\n<td>RQTRR</td>\n<td>release qualification test readiness review</td>\n</tr>\n<tr>\n<td>RRR</td>\n<td>release requirements review</td>\n</tr>\n<tr>\n<td>SCM</td>\n<td>software configuration management</td>\n</tr>\n<tr>\n<td>SCR</td>\n<td>system concept review</td>\n</tr>\n<tr>\n<td>SDR</td>\n<td>system design review</td>\n</tr>\n<tr>\n<td>SDS</td>\n<td>system design specification</td>\n</tr>\n<tr>\n<td>SEI</td>\n<td>Software Engineering Institute</td>\n</tr>\n<tr>\n<td>SEL</td>\n<td>Software Engineering Laboratory</td>\n</tr>\n<tr>\n<td>SPR</td>\n<td>system or software problem report</td>\n</tr>\n<tr>\n<td>SQA</td>\n<td>software quality assurance</td>\n</tr>\n<tr>\n<td>SRR</td>\n<td>system requirements review</td>\n</tr>\n<tr>\n<td>SRS</td>\n<td>system requirements specification</td>\n</tr>\n<tr>\n<td>SSR</td>\n<td>software specification review</td>\n</tr>\n<tr>\n<td>STR</td>\n<td>system or software trouble report</td>\n</tr>\n<tr>\n<td>SWDS</td>\n<td>software design specification</td>\n</tr>\n<tr>\n<td>SWG</td>\n<td>Software Working Group</td>\n</tr>\n<tr>\n<td>SWRS</td>\n<td>software requirements specification</td>\n</tr>\n<tr>\n<td>TBD</td>\n<td>to be determined</td>\n</tr>\n<tr>\n<td>TPM</td>\n<td>Technical Performance Measurement</td>\n</tr>\n<tr>\n<td>V&V</td>\n<td>validation and verification (also validate and verify)</td>\n</tr>\n</tbody>\n</table>\nReferences\n\n1. Profile of Software at the National Aeronautics and Space Administration (NASA), Software Engineering Program, NASA-RPT-004-95, March 1995.\n\n\n18. NASA Management Instruction 7120.4, “Management of Major System Programs and\n\n\n"}}},{"rowIdx":99,"cells":{"id":{"kind":"string","value":"e2b71d7031ec6ca7a5b171920e8c6edd35bd7d02"},"text":{"kind":"string","value":"EEPROM Emulation Library\n\nType T02 (Tiny), European Release\n\n16 Bit Single-chip Microcontroller\nRL78 Family\n\nInstaller:\nRENESAS_RL78_EEL-FDL_T02_PACK02_xVxx\n\nAll information contained in these materials, including products and product specifications, represents information on the product at the time of publication and is subject to change by Renesas Electronics Corp. without notice. Please review the latest information published by Renesas Electronics Corp. through various means, including the Renesas Technology Corp. website (http://www.renesas.com).\nNotice\n\n1. Descriptions of circuits, software and other related information in this document are provided only to illustrate the operation of semiconductor products and application examples. You are fully responsible for the incorporation or any other use of the circuits, software, and information in the design of your product or system. Renesas Electronics disclaims any and all liability for any losses and damages incurred by you or third parties arising from the use of these circuits, software, or information.\n\n2. Renesas Electronics hereby expressly disclaims any warranties against and liability for infringement or any other claims involving patents, copyrights, or other intellectual property rights of third parties, by or arising from the use of Renesas Electronics products or technical information described in this document, including but not limited to, the product data, drawings, charts, programs, algorithms, and application examples.\n\n3. No license, express, implied or otherwise, is granted hereby under any patents, copyrights or other intellectual property rights of Renesas Electronics or others.\n\n4. You shall not alter, modify, copy, or reverse engineer any Renesas Electronics product, whether in whole or in part. Renesas Electronics disclaims any and all liability for any losses or damages incurred by you or third parties arising from such alteration, modification, copying or reverse engineering.\n\n5. Renesas Electronics products are classified according to the following two quality grades: “Standard” and “High Quality”. The intended applications for each Renesas Electronics product depends on the product’s quality grade, as indicated below.\n\n “Standard”: Computers; office equipment; communications equipment; test and measurement equipment; audio and visual equipment; home electronic appliances; machine tools; personal electronic equipment; industrial robots; etc.\n\n “High Quality”: Transportation equipment (automobiles, trains, ships, etc.); traffic control (traffic lights); large-scale communication equipment; key financial terminal systems; safety control equipment; etc.\n\n Unless expressly designated as a high reliability product or a product for harsh environments in a Renesas Electronics data sheet or other Renesas Electronics document, Renesas Electronics products are not intended or authorized for use in products or systems that may pose a direct threat to human life or bodily injury (artificial life support devices or systems; surgical implantations; etc.), or may cause serious property damage (space system; undersea repeaters; nuclear power control systems; aircraft control systems; key plant systems; military equipment; etc.). Renesas Electronics disclaims any and all liability for any damages or losses incurred by you or any third parties arising from the use of any Renesas Electronics product that is inconsistent with any Renesas Electronics data sheet, user’s manual or other Renesas Electronics document.\n\n6. When using Renesas Electronics products, refer to the latest product information (data sheets, user’s manuals, application notes, “General Notes for Handling and Using Semiconductor Devices” in the reliability handbook, etc.), and ensure that usage conditions are within the ranges specified by Renesas Electronics with respect to maximum ratings, operating power supply voltage range, heat dissipation characteristics, installation, etc. Renesas Electronics disclaims any and all liability for any malfunctions, failure or accident arising out of the use of Renesas Electronics products outside of such specified ranges.\n\n7. Although Renesas Electronics endeavors to improve the quality and reliability of Renesas Electronics products, semiconductor products have specific characteristics, such as the occurrence of failure at a certain rate and malfunctions under certain use conditions. Unless designated as a high reliability product or a product for harsh environments in a Renesas Electronics data sheet or other Renesas Electronics document, Renesas Electronics products are not subject to radiation resistance design. You are responsible for implementing safety measures to guard against the possibility of bodily injury, injury or damage caused by fire, and/or danger to the public in the event of a failure or malfunction of Renesas Electronics products, such as safety design for hardware and software, including but not limited to redundancy, fire control and malfunction prevention, appropriate treatment for aging degradation or any other appropriate measures. Because the evaluation of microcomputer software alone is very difficult and impractical, you are responsible for evaluating the safety of the final products or systems manufactured by you.\n\n8. Please contact a Renesas Electronics sales office for details as to environmental matters such as the environmental compatibility of each Renesas Electronics product. You are responsible for carefully and sufficiently investigating applicable laws and regulations that regulate the inclusion or use of controlled substances, including without limitation, the EU RoHS Directive, and using Renesas Electronics products in compliance with all these applicable laws and regulations. Renesas Electronics disclaims any and all liability for damages or losses occurring as a result of your noncompliance with applicable laws and regulations.\n\n9. Renesas Electronics products and technologies shall not be used for or incorporated into any products or systems whose manufacture, use, or sale is prohibited under any applicable domestic or foreign laws or regulations. You shall comply with any applicable export control laws and regulations promulgated and administered by the governments of any countries asserting jurisdiction over the parties or transactions.\n\n10. It is the responsibility of the buyer or distributor of Renesas Electronics products, or any other party who distributes, disposes of, or otherwise sells or transfers the product to a third party, to notify such third party in advance of the contents and conditions set forth in this document.\n\n11. This document shall not be reprinted, reproduced or duplicated in any form, in whole or in part, without prior written consent of Renesas Electronics.\n\n12. Please contact a Renesas Electronics sales office if you have any questions regarding the information contained in this document or Renesas Electronics products.\n\n(Note 1) “Renesas Electronics” as used in this document means Renesas Electronics Corporation and also includes its directly or indirectly controlled subsidiaries.\n\n(Note 2) “Renesas Electronics product(s)” means any product developed or manufactured by or for Renesas Electronics.\nRegional information\n\nSome information contained in this document may vary from country to country. Before using any Renesas Electronics product in your application, please contact the Renesas Electronics office in your country to obtain a list of authorized representatives and distributors. They will verify:\n\n- Device availability\n- Ordering information\n- Product release schedule\n- Availability of related technical literature\n- Development environment specifications (for example, specifications for third-party tools and components, host computers, power plugs, AC supply voltages, and so forth)\n- Network requirements\n\nIn addition, trademarks, registered trademarks, export restrictions, and other legal issues may also vary from country to country.\n\nVisit [http://www.renesas.com](http://www.renesas.com)\n\nto get in contact with your regional representatives and distributors.\n# Preface\n\n## Readers\nThis manual is intended for users who want to understand the functions of the concerned libraries.\n\n## Purpose\nThis manual presents the software manual for the concerned libraries.\n\n## Numeric notation\n<table>\n<thead>\n<tr>\n<th>Binary:</th>\n<th>xxxx or xxxB</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Decimal:</td>\n<td>xxxx</td>\n</tr>\n<tr>\n<td>Hexadecimal:</td>\n<td>xxxxH or 0x xxxx</td>\n</tr>\n</tbody>\n</table>\n\n## Numeric prefix\nRepresenting powers of 2 (address space, memory capacity):\n\n- **K (kilo):** \\(2^{10} = 1024\\)\n- **M (mega):** \\(2^{20} = 1024^2 = 1,048,576\\)\n- **G (giga):** \\(2^{30} = 1024^3 = 1,073,741,824\\)\n\n## Register\nX, x = don’t care\n\n## Diagrams\nBlock diagrams do not necessarily show the exact software flow but the functional structure. Timing diagrams are for functional explanation purposes only, without any relevance to the real hardware implementation.\n(1) Purpose and Target Readers\n\nThis manual is designed to provide the user with an understanding of the hardware functions and electrical characteristics of the MCU. It is intended for users designing application systems incorporating the MCU. A basic knowledge of electric circuits, logical circuits, and MCUs is necessary in order to use this manual. The manual comprises an overview of the product; descriptions of the CPU, system control functions, peripheral functions, and electrical characteristics; and usage notes.\n\nParticular attention should be paid to the precautionary notes when using the manual. These notes occur within the body of the text, at the end of each section, and in the Usage Notes section.\n\nThe revision history summarizes the locations of revisions and additions. It does not list all revisions. Refer to the text of the manual for details.\n\n(2) Related documents\n\n<table>\n<thead>\n<tr>\n<th>Document number</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>R01US0061EDxxxx</td>\n<td>Data Flash Access Library Type T02 (Tiny), European Release</td>\n</tr>\n</tbody>\n</table>\n\n(3) List of Abbreviations and Acronyms\n\n<table>\n<thead>\n<tr>\n<th>Abbreviation</th>\n<th>Full form</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>API</td>\n<td>Application Programming Interface</td>\n</tr>\n<tr>\n<td>Code Flash</td>\n<td>Embedded Flash where the application code or constant data is stored.</td>\n</tr>\n<tr>\n<td>Data Flash</td>\n<td>Embedded Flash where mainly the data of the EEPROM emulation are stored.</td>\n</tr>\n<tr>\n<td>Data Set</td>\n<td>Instance of data written to the Flash by the EEPROM Emulation Library (EEL), identified by the Data Set ID</td>\n</tr>\n<tr>\n<td>DS</td>\n<td>Short for Data Set</td>\n</tr>\n<tr>\n<td>Dual Operation</td>\n<td>Dual operation is the capability to access flash memory during reprogramming another flash memory range. Dual operation is available between Code Flash and Data Flash. Between different Code Flash macros dual operation depends on the device implementation.</td>\n</tr>\n<tr>\n<td>ECC</td>\n<td>Error Correction Code</td>\n</tr>\n<tr>\n<td>EEL</td>\n<td>EEPROM Emulation Library</td>\n</tr>\n<tr>\n<td>EEPROM</td>\n<td>Electrically erasable programmable read-only memory</td>\n</tr>\n<tr>\n<td>EEPROM emulation</td>\n<td>In distinction to a real EEPROM the EEPROM emulation uses some portion of the flash memory to emulate the EEPROM behavior. To gain a similar behavior some side parameters have to be taken in account.</td>\n</tr>\n<tr>\n<td>FAL</td>\n<td>Flash Access Library (Flash access layer)</td>\n</tr>\n<tr>\n<td>FCL</td>\n<td>Code Flash Library (Code Flash access layer)</td>\n</tr>\n<tr>\n<td>FDL</td>\n<td>Data Flash Library (Data Flash access layer)</td>\n</tr>\n<tr>\n<td>Abbreviation</td>\n<td>Full form</td>\n</tr>\n<tr>\n<td>--------------</td>\n<td>-----------</td>\n</tr>\n<tr>\n<td>Firmware</td>\n<td>The Firmware is a piece of software that is located in a hidden area of the device, handling the interfacing to the flash.</td>\n</tr>\n<tr>\n<td>Flash</td>\n<td>Electrically erasable and programmable nonvolatile memory. The difference to ROM is, that this type of memory can be re-programmed several times.</td>\n</tr>\n<tr>\n<td>Flash Area</td>\n<td>Area of Flash consists of several coherent Flash Blocks</td>\n</tr>\n<tr>\n<td>Flash Block</td>\n<td>A flash block is the smallest erasable unit of the flash memory.</td>\n</tr>\n<tr>\n<td>Flash Macro</td>\n<td>A certain number of Flash blocks is grouped together in a Flash macro.</td>\n</tr>\n<tr>\n<td>FW</td>\n<td>Firmware</td>\n</tr>\n<tr>\n<td>ID</td>\n<td>Identifier of a Data Set instance in the Renesas EEPROM Emulation</td>\n</tr>\n<tr>\n<td>MF3</td>\n<td>Name of the Flash technology used in RL78 devices.</td>\n</tr>\n<tr>\n<td>NVM</td>\n<td>Non-volatile memory. All memories that hold the value, even when the power is cut off. E.g. Flash memory, EEPROM, MRAM...</td>\n</tr>\n<tr>\n<td>RAM</td>\n<td>Random access memory. Volatile memory with random access</td>\n</tr>\n<tr>\n<td>REE</td>\n<td>Renesas Electronics Europe GmbH</td>\n</tr>\n<tr>\n<td>REL</td>\n<td>Renesas Electronics Japan</td>\n</tr>\n<tr>\n<td>ROM</td>\n<td>Read only memory. Non-volatile memory. The content of that memory cannot be changed.</td>\n</tr>\n<tr>\n<td>Segment / Section</td>\n<td>Segment of Flash is a part of the flash that might consist of several blocks. Important is, that this segment can be protected against manipulation.</td>\n</tr>\n<tr>\n<td>Self-Programming</td>\n<td>Capability to reprogram the embedded flash without external programming tool only via control code running on the microcontroller.</td>\n</tr>\n<tr>\n<td>Serial programming</td>\n<td>The onboard programming mode is used to program the device with an external programmer tool.</td>\n</tr>\n</tbody>\n</table>\n\nAll trademarks and registered trademarks are the property of their respective owners.\n# Table of Contents\n\nChapter 1 Introduction ................................................................. 10\n 1.1 Flash Infrastructure ................................................................. 10\n 1.1.1 Dual Operation ................................................................. 10\n 1.1.2 Flash Granularity ............................................................. 11\n 1.2 Feature Overview ................................................................. 11\n\nChapter 2 Architecture ............................................................... 12\n 2.1 Layered Software Architecture ............................................... 12\n 2.2 Data Flash Pool Structure ....................................................... 13\n 2.2.1 FDL pool ...................................................................... 14\n 2.2.2 EEL Pool ..................................................................... 14\n 2.3 EEL Management ................................................................. 14\n 2.3.1 EEL Pool Structure ......................................................... 14\n 2.3.2 EEL Block Structure ....................................................... 16\n 2.3.3 Structure of Variable Instances ....................................... 18\n 2.3.4 EEL Block Overview ....................................................... 19\n\nChapter 3 EEL Operation .............................................................. 20\n 3.1 Functions and Commands ....................................................... 20\n 3.1.1 EEL Functions ............................................................... 20\n 3.1.2 EEL Commands ............................................................. 20\n 3.1.3 Request-Response-oriented Dialog .................................... 21\n 3.1.4 Handler-oriented Command Execution ............................... 21\n 3.2 Basic Workflow ................................................................. 23\n\nChapter 4 Application Programming Interface (API) .................... 26\n 4.1 Data Types ............................................................................ 26\n 4.1.1 Library-specific Simple-Type Definitions ............................ 26\n 4.1.2 eel_command_t ............................................................... 27\n 4.1.3 eel_driver_status_t ........................................................ 28\n 4.1.4 eel_status_t ................................................................. 29\n 4.1.5 eel_request_t ............................................................... 31\n 4.1.6 eel_descriptor .............................................................. 32\n 4.2 Functions ............................................................................. 33\n 4.2.1 EEL_Init ................................................................. 33\n 4.2.2 EEL_Open ............................................................... 36\n 4.2.3 EEL_Close ............................................................... 38\n 4.2.4 EEL_Execute ............................................................ 40\n<table>\n<thead>\n<tr>\n<th>Section</th>\n<th>Page</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>4.2.5 EEL_Handler</td>\n<td>42</td>\n</tr>\n<tr>\n<td>4.2.6 EEL_GetDriverStatus</td>\n<td>44</td>\n</tr>\n<tr>\n<td>4.2.7 EEL_GetSpace</td>\n<td>46</td>\n</tr>\n<tr>\n<td>4.2.8 EEL_GetVersionString</td>\n<td>49</td>\n</tr>\n<tr>\n<td>4.3 Commands</td>\n<td>51</td>\n</tr>\n<tr>\n<td>4.3.1 Startup</td>\n<td>54</td>\n</tr>\n<tr>\n<td>4.3.2 Verify</td>\n<td>56</td>\n</tr>\n<tr>\n<td>4.3.3 Shutdown</td>\n<td>57</td>\n</tr>\n<tr>\n<td>4.3.4 Format</td>\n<td>58</td>\n</tr>\n<tr>\n<td>4.3.5 Refresh</td>\n<td>60</td>\n</tr>\n<tr>\n<td>4.3.6 Write</td>\n<td>62</td>\n</tr>\n<tr>\n<td>4.3.7 Read</td>\n<td>64</td>\n</tr>\n<tr>\n<td>4.3.8 Code examples</td>\n<td>66</td>\n</tr>\n<tr>\n<td>Chapter 5 Library Setup and Usage</td>\n<td>71</td>\n</tr>\n<tr>\n<td>5.1 Obtaining the Library</td>\n<td>71</td>\n</tr>\n<tr>\n<td>5.2 File Structure</td>\n<td>71</td>\n</tr>\n<tr>\n<td>5.3 Library Resources</td>\n<td>73</td>\n</tr>\n<tr>\n<td>5.3.1 Resource Consumption</td>\n<td>73</td>\n</tr>\n<tr>\n<td>5.3.2 Linker Sections</td>\n<td>74</td>\n</tr>\n<tr>\n<td>5.3.3 Prohibited RAM Area</td>\n<td>74</td>\n</tr>\n<tr>\n<td>5.3.4 Stack and Data Buffer</td>\n<td>74</td>\n</tr>\n<tr>\n<td>5.3.5 Register Usage</td>\n<td>75</td>\n</tr>\n<tr>\n<td>5.3.6 Library Timings</td>\n<td>75</td>\n</tr>\n<tr>\n<td>5.4 Library Setup</td>\n<td>77</td>\n</tr>\n<tr>\n<td>5.4.1 EEL Pool Configuration</td>\n<td>77</td>\n</tr>\n<tr>\n<td>5.4.2 Endurance Calculation</td>\n<td>77</td>\n</tr>\n<tr>\n<td>5.4.3 EEL Variable Configuration</td>\n<td>78</td>\n</tr>\n<tr>\n<td>5.4.4 EEL Variable Initialization</td>\n<td>79</td>\n</tr>\n<tr>\n<td>5.4.5 Distributing Data between FDL and EEL</td>\n<td>79</td>\n</tr>\n<tr>\n<td>5.4.6 Building Efficient EEL Variable Sets</td>\n<td>79</td>\n</tr>\n<tr>\n<td>5.5 Practical Aspects of Library Usage</td>\n<td>79</td>\n</tr>\n<tr>\n<td>5.5.1 When to use EEL_Handler and FDL_Handler</td>\n<td>80</td>\n</tr>\n<tr>\n<td>5.5.2 EEL_Handler Calls</td>\n<td>80</td>\n</tr>\n<tr>\n<td>5.5.3 When to issue a Refresh</td>\n<td>81</td>\n</tr>\n<tr>\n<td>5.5.4 Using the Standby and Abort Feature of the Tiny FDL</td>\n<td>81</td>\n</tr>\n<tr>\n<td>5.5.5 Using the Tiny EEL in Operating Systems</td>\n<td>82</td>\n</tr>\n<tr>\n<td>5.5.6 Reset Robustness Considerations</td>\n<td>83</td>\n</tr>\n</tbody>\n</table>\n5.5.7 Pitfalls with Request Variables declared in a local Scope ...............83\n\nChapter 6 Cautions .........................................................................................84\nChapter 1 Introduction\n\nThis user manual describes the internal structure, the functionality and the application programming interface (API) of the Renesas RL78 EEPROM Emulation Library (EEL) Type 02, designed for RL78 flash devices with Data Flash based on the MF3 flash technology.\n\nWhile many RL78 devices are equipped with Data flash, a direct usage of this non-volatile memory can be more complex than the usage of classical electrically erasable programmable read-only memory (EEPROM), as erases of flash memory can only be performed block-wise, i.e. on rather large continuous address ranges. Furthermore, the number of program-erase cycles for each flash block is finite and demands for effective data management and wear-leveling techniques.\n\nThe EEPROM Emulation Library described in this document addresses these challenges by providing a simple-to-use software interface to the developers, encapsulating the detailed flash management with a framework based on emulated variables. The developer can access (read and write) these variables independently in an EEPROM-like manner. This way, the developer can concentrate on the actual functionality of the application rather than spending time on tedious details of Data Flash access sequences.\n\nThe Renesas RL78 EEPROM Emulation Library Type 02 (from here on referred to as Tiny EEL) provides APIs for the C and assembly language of the CA78K0R, IAR V1.xx, IAR V2.xx, GNU and CC-RL tool chains. (APIs for the assembly language are provided by the CA78K0R and CC-RL tool chains only.) The Tiny EEL for IAR V2.xx tool chain (except linker sample file) can also be used with the IAR V3.xx and IAR V4.xx tool chains.\n\nIn contrast to the also available EEL Type 01 for RL78 devices, the Tiny EEL was especially designed for reduced resource consumption (in terms of Code Flash, Data Flash and RAM) in order to bring EEPROM emulation also to small RL78 devices. As a result, the number of features and the maximum manageable data has been reduced in this library (see Section 1.2 for details).\n\nThe EEPROM emulation library, the latest version of this user manual and other device dependent information can be downloaded from the following URL:\n\n\nPlease ensure to always use the latest release of the library in order to take advantage of improvements and bug fixes.\n\nThe Tiny EEL requires the corresponding RL78 Data Flash Access Library (FDL) Type 02 (Tiny FDL) for operation. It can be obtained from the same URL as the Tiny EEL. Please ensure to always use the correct release of the FDL which is specified inside the EEL release in order to avoid incompatibilities between the two libraries.\n\nNote:\nPlease read all chapters of this user manual carefully. Much attention has been put to proper description of usage conditions and limitations. Anyhow, it can never be completely ensured that all incorrect ways of integrating the library into the user application are explicitly forbidden. So, please follow the given sequences and recommendations in this document exactly in order to make full use of the library functionality and features and in order to avoid malfunctions caused by library misuse.\n\n1.1 Flash Infrastructure\n\nThe flash technology which is utilized in RL78 devices is called MF3. Besides the Code Flash, many devices of the RL78 microcontroller family are equipped with a separate flash area—the Data Flash. This flash area is meant to be used exclusively for data. It cannot be used for instruction execution (code fetching).\n\n1.1.1 Dual Operation\n\nCommon for all Flash implementations is, that during Flash modification operations (Erase/Write) a certain amount of Flash memory is not accessible for any read operation (e.g. program execution or data read).\nThis does not only concern the modified Flash range, but a certain part of the complete Flash system. The amount of not accessible Flash depends on the device architecture.\n\nA standard architectural approach is the separation of the Flash into Code Flash and Data Flash. By that, it is possible to fetch instruction code from the Code Flash (to execute program) while data are read or written into Data Flash. This allows implementation of EEPROM emulation concepts running quasi in parallel to the application software without significant impact on its execution timing.\n\nIf not mentioned otherwise in the device user's manuals, RL78 devices with Data Flash are designed according to this standard approach.\n\nNote:\nIt is not possible to modify Code Flash and Data Flash in parallel.\n\n1.1.2 Flash Granularity\n\nThe MF3 Data Flash of RL78 devices is separated into blocks of 1024 byte. While erase operations can only be performed on complete blocks, reading and writing of data can be done on a granularity of bytes or byte sequences. Reading from an erased MF3 flash byte will return the value 0xFF. The number of available Data Flash blocks varies between the different RL78 devices. Please refer to the corresponding user's manual of your device for detailed information.\n\n1.2 Feature Overview\n\nThe Tiny EEL offers easy-to-use EEPROM-like access to user-defined variable sets stored in the non-volatile Data Flash memory of RL78 microcontrollers. Aiming at low resource consumption, the Tiny EEL offers a basic function set to designers covering the following features:\n\n- Up to 64 independent variables\n- Configurable variable sizes between 1 and 255 byte\n- Polling operation mode\n- Minimized storage consumption for administrative data (10 bytes per flash block and 2 bytes per variable instance)\n- Reset resistance\n- Block rotation (balanced data flash usage)\n- Applicability in operating systems\n- Standby functionality for energy savings (via Tiny FDL)\n- Resistance against aborted block erasures (via Tiny FDL)\n\nBesides the Tiny EEL, which is the subject of this documentation, Renesas offers another EEL, the EEPROM Emulation Library Type 01. Compared to this more resource intensive library, the Tiny EEL offers a reduced set of features and functions (for more details on these features, please refer to the EEL Type 01 user manual R01US0128EDxxxx):\n\n- No enforced and timing mode\n- Only one EEL flash block is utilized for storing data at a time resulting in a limited number and size of variables\n- No background maintenance process (i.e. refreshing of the EEL pool needs to be directly triggered from the user application)\n- The variable ID is predefined by the order within the descriptor and cannot be selected arbitrarily\n- No automatic checksums on data content\n\nIf you are unsure which EEL is the best choice for your project, please contact the Renesas support team at application_support.flash-eu@lm.renesas.com.\nChapter 2 Architecture\n\nThis chapter introduces the basic software architecture of the Tiny EEL and provides the necessary background for application designers to understand and effectively use the Tiny EEL. Please read this chapter carefully before moving on to the details of the API description.\n\n2.1 Layered Software Architecture\n\nThe EEPROM emulation system is built up from several hierarchical functional blocks. This user manual concentrates on the functionality and usage of the EEL. However, a short description of all involved functional blocks and their relationship is important for the general understanding of the concepts and usage of the EEL.\n\nAs depicted in Figure 2-1, the software architecture of the EEPROM emulation system is built up of several layers:\n\n- **Physical flash layer**: The Data Flash is a separate memory that can be accessed independent of the Code Flash memory. This allows background access to data stored in the Data Flash during program execution from the code flash.\n\n- **Flash access layer**: The Data Flash access layer is represented by the Data Flash Access Library (FDL) provided by Renesas. It offers an easy-to-use API to access and manage the Data Flash by encapsulating and abstracting tedious timing and flash access sequence details.\n\n- **EEPROM layer**: The EEPROM layer allows read/write access to the Data Flash on an abstract level. It is represented by a Renesas EEL (as described in this document) or alternatively any other, user specific implementation.\n\n- **Application layer**: The application layer covers the user’s application software which has access to the Data Flash by using functions and commands of the lower layers.\n\nThe EEL does not directly access the Data Flash. The Data Flash is always accessed via the Data Flash Library (FDL). This way, the designer can use both FDL and EEL simultaneously to access the Data Flash. Of course this does not mean that the multiple accesses are handled in parallel. However, the libraries are particularly designed to not to interfere with each other and are robust against interleaved mixed Data Flash accesses via the opposite library.\nA parallel usage of FDL and EEL is strongly encouraged. Depending on the data to be stored, each library has its advantages and disadvantages. While the FDL enables an efficient way to store data which is changed very seldom (e.g. configuration parameters or constant identification numbers) and offers the designer full freedom how to manage the data, the EEL provides a comfortable way to handle frequently changing data sets at the cost of a mean resource overhead.\n\n2.2 Data Flash Pool Structure\n\nThe decision for using FDL or EEL as Data Flash access mechanism is usually driven by characteristics of the data, in particular how often the data needs to be updated, reset robustness and the application overhead to access and manage the data. As a result it is often desirable to use both libraries within the same application. Consequently, the Data Flash is separated into two individual pools: The FDL pool and the EEL pool.\n\nThis separation is also necessary as the EEL stores additional administrative data in the blocks of the EEL pool for managing the blocks and the instances of variables. In order to avoid FDL handling errors which might corrupt the EEL data structures, the API structure and the sanity checks of both libraries ensure that the user application has only access to each pool via the corresponding library as shown in Figure 2-2. The EEL uses dedicated subroutines of the FDL which are hidden from the user and exclusively reserved for the EEL.\n\nThe distribution of the available Data Flash to EEL and FDL pool can be configured at compile time in the descriptor of the FDL (see the RL78 FDL T02 user manual for details of the Tiny FDL configuration options). Please note that the assignment of Data Flash memory to FDL and EEL pool can only be done on a flash-block basis. The EEL pool always maps to the Data Flash blocks with the lower addresses in the device memory map.\n2.2.1 FDL pool\n\nThe FDL pool allocates the Data Flash blocks that are directly managed by the user application via the Tiny FDL. It can be used to simply store constants or to even build up an own user EEPROM emulation. Please note however, that it is the designers duty to take care of reset and failure scenarios himself when using the FDL, e.g. by a proper failure mode and effects analysis.\n\n2.2.1.1 Direct Data Flash Access through Address Virtualization\n\nIn order to simplify the flash content handling, the physical addresses used by the flash hardware were transformed into a linear 16-bit index addressing (8-bit units) inside the FDL pool. By this measure, the FDL pool can be treated as a simple array of words. To address the array elements (read/write access), word-indexes starting at 0x0000 can be used. The maximum range of the word-index depends on the pool configuration, i.e. the number of flash blocks reserved for the FDL pool.\n\n2.2.2 EEL Pool\n\nThe EEL pool allocates the Data Flash blocks that are used by the EEPROM emulation to store user content and administrative data. The handling of the flash blocks is completely encapsulated in the EEL and abstracted through the EEL API. The direct access to this pool via the FDL is not possible.\n\n2.2.2.1 Automated Data Flash Management through Variable Virtualization\n\nWhile the data stored in the FDL pool needs to be managed completely by the user application, the usage of the EEL pool is greatly simplified by variable virtualization. The user defines a set of variables with individual sizes at compile time. These Variables can be read and written via dedicated commands of the EEL API during runtime. Pool handling and reset-safe variable update processes help the developer to concentrate on the actual functionality of the application rather than detailed flash-access sequences.\n\n2.3 EEL Management\n\nWhile the simple usage of the Tiny EEL via its API hides many complex management issues from the developer, it is still mandatory to understand the management mechanisms of the library in order to use it efficiently. Therefore, the EEL management is introduced in the following by first specifying the structures of the EEL pool, blocks and variables. Afterwards, the transitions, sequences and processes within the EEL are highlighted briefly.\n\n2.3.1 EEL Pool Structure\n\nIn the Tiny EEL, the EEL pool is separated into blocks of 1 KB size, which match the physical block separation of the Data Flash. Each block has a status which indicates the current usage of the block. The status of an EEL block is one of the following:\n\n- **Active**: Due to the strong resource limitations applied for the Tiny EEL, only one EEL block is active at a time and stores values for the defined EEL variables (assuming normal operation). During lifetime, the currently active block rotates through the Data Flash blocks assigned to the EEL pool.\n- **Invalid**: Invalid blocks do not store any EEL variable values. Blocks are either actively marked as invalid by the library or are invalid due to unstructured content (e.g. in case of an erased block).\n- **Excluded**: Whenever functional operations on a block fail too often indicating a damaged Data Flash, the EEL actively excludes the corresponding block and does not use this block for EEPROM emulation anymore.\n\nFigure 2-3 shows an exemplary pool configuration for a device with 8 KB Data Flash, where three blocks are assigned to the FDL pool and the EEL operates on 5 blocks.\n\nWhenever the active block (block 1 in the example) is full and cannot store additional data (i.e. a write command fails), a new active block is selected in a cyclic manner and the current valid data set is copied to this new active block. This process is referred to as refresh. The former active block is invalidated during a refresh, so that there is only one active block at a time. Excluded blocks (like block 4 in the\nexample) are ignored during this process and not considered as candidates for the selection of the next active block.\n\n\n\n\n\n\n\n**Figure 2-3: Exemplary EEL pool constellation**\n\n**Note:**\nAlthough only one block is active in the Tiny EEL at a time, it makes sense to assign several blocks to the EEL pool. This way, hot spots on one block are reduced and wear leveling is improved. On the one hand, this means that the number of erases for one block is effectively reduced increasing the lifetime of the device. On the other hand, it enables a larger number of variable updates (writes) during the device life cycle.\n\nThe overall life cycle of a block in the EEL pool is shown in Figure 2-4. During normal operation, the block switches between active and invalid status. In case of a repeated error during block accessing, the affected flash block is considered to be defect and is marked as excluded. This block will not enter the lifecycle again. However, the user can try to reanimate the block by a format of the complete pool-which also erases all existing variable content (see Section 4.3.4 for details of the format command).\n\n\n\n**Figure 2-4: Life cycle of an EEL block**\nNot only the status of each EEL block is classified. There are also four different statuses of the overall EEL pool that can be distinguished:\n\n- **Pool operational**: This is the usual case during EEL operation. All commands are available and can be executed.\n- **Pool full**: The current active block is full and does not have enough space left to perform a write. This is a usual situation during library operation and indicates that a refresh needs to be executed. (There is a correlation with the size of the variable to be written.)\n- **Pool exhausted**: Too many blocks have been excluded for full operation of the library. (The Tiny EEL requires at least two non-excluded blocks for operation.) Reading variables and verification of the active block is still possible, however writing variables and a refresh cannot be executed anymore. A reanimation of the library can only be attempted by a format of the pool.\n- **Pool inconsistent**: The pool is not consistent, i.e. the data structures found in the EEL blocks do not match the expected structures of EEL blocks. Typically, this is the case when the pool has not yet been formatted with the Tiny EEL or when the pool content has been corrupted by flashing the device.\n\n### 2.3.2 EEL Block Structure\n\nThe detailed block structure used by the Tiny EEL is depicted in Figure 2-5. In general, an EEL block is divided into three utilized areas: the block header, the reference area and the data area.\n\n\n\nThe individual purpose of each area is given in the following:\n\n- **Block header**: The block header contains all block status information needed for the block management within the EEL-pool. It has a fixed size of 8 bytes.\n• **Reference area:** The reference area contains reference entries which are required for the management of EEL variables. It grows in direction of larger indexes whenever a variable is written.\n\n• **Data area:** The data area contains the pure data values of the defined EEL variables. It grows in direction of smaller indexes whenever a variable is written.\n\nBetween reference and data area, there is an erased area of not-written flash cells (erased flash cells in MF3 have a value of 0xFF). With each EEL variable update (i.e. the variable is written), this area is reduced successively. However, at least two bytes of space always remain between reference and data area for management and separation of these areas. This is indicated by the separator in Figure 2-5.\n\nThe EEL block header is detailed in the following, while the structure of variable instances stored in the reference and data area are described in Section 2.3.3.\n\n### 2.3.2.1 EEL Block Header\n\nThe block header is a small area at the top of each flash block belonging to the EEL pool. It contains all information necessary for block management during EEL operation. The structure of the block header is depicted in Figure 2-6. It is composed of eight bytes, four of which are reserved for future use.\n\n\n\nInside the header area, a set of status flags is used to code the block status in a reset-resistant manner. Each of the four flags has a size of one byte and fulfills the following purpose:\n\n• **A and B flag:** The A and B flag are used to indicate the activation of a block. In case of an active block, the value of A falls in the range between 0x01 and 0x03, while the B flag contains the binary complement of A. In case of any other A/B-flag combination, the block is treated as invalid. Table 2-1 shows the possible A/B-flag combinations together with the corresponding block status.\n\n<table>\n<thead>\n<tr>\n<th>A(x)</th>\n<th>B(x)</th>\n<th>Block x status</th>\n<th>Comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>0x01</td>\n<td>0xFE</td>\n<td>active</td>\n<td>0x01 is always older than 0x02</td>\n</tr>\n<tr>\n<td>0x02</td>\n<td>0xFD</td>\n<td>active</td>\n<td>0x02 is always older than 0x03</td>\n</tr>\n<tr>\n<td>0x03</td>\n<td>0xFC</td>\n<td>active</td>\n<td>0x03 is always older than 0x01</td>\n</tr>\n<tr>\n<td>other combination</td>\n<td>invalid</td>\n<td>other values are irregular</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\n• **I flag:** By means of the I flag, a block can be actively marked as invalid. The I flag is treated as a destructive flag, meaning that any value different from 0xFF (value of an erased cell) indicates an invalid block. The I flag overrules any status information of the A/B flag. Several processes of the EEL use this mechanism of active invalidation in order to achieve a consistent pool constellation.\n\n• **X flag:** The X flag is a destructive flag used to exclude blocks from the block management. Any value different from 0xFF indicates an excluded block. The X flag overrules all other block flags. The only one way to reactivate a once excluded block is to format the whole EEL pool.\n2.3.3 Structure of Variable Instances\n\nBy means of the so-called EEL descriptor, the developer can configure a set of variables to be used within the EEL. Each variable is referred to by an identification number (ID) and can have a size between 1 and 255 byte. (The exact specification of the format of the EEL descriptor can be found in Section 5.4.3.)\n\nWhenever a variable content is updated, i.e. the variable is written, a new *instance* of the variable is written to the active block. This means that there can be multiple instances of a variable at a time. However, only the newest instance is considered and referred to when reading the variable.\n\nA variable instance is composed of three parts: the start-of-record (SoR) field the end-of-record (EoR) field and the data field. SoR and EoR build up the so-called *reference* which is required for the management of the variable instance. The reference entry and data values are stored in different sections of the active block, namely the reference area and the data area, respectively.\n\nThe overall structure of a variable instance is abstracted in Figure 2-7. A more precise description of the three different fields of an instance is given in the following:\n\n- **SoR field**: The 1-byte SoR field contains the ID code of the corresponding EEL variable. It indicates the start of a write sequence as described later in this section. The IDs 0x00 and 0xFF are never used and illegal in order to avoid patterns of erased cells.\n\n- **EoR field**: The 1-byte EoR field contains the binary inversion of ID code. It indicates the successful end of a write sequence. When not completely written—e.g. due to a reset of the device—the corresponding instance is ignored by the EEL.\n\n- **Data field**: The data field contains the net data of the EEL variable. The size of the data field matches the size of the corresponding variable and ranges from 1 to 255 bytes. Lower variable indices (in case of multi-byte variables) are stored at lower addresses in the data section of the active block.\n\n**Note 1:**\nThe total size of the reference consumed by each variable instance is 2 bytes. This should be considered when evaluating the free space in a block before writing the variable through the EEL_GetSpace function (see Section 4.2.7).\n\n**Note 2:**\nDue to strict resource limitations applied for the Tiny EEL, the data field is not protected automatically by any checksum. If required, the developer can integrate such checksums in the net data of the variable manually.\n2.3.4 EEL Block Overview\n\nPutting together the information of the previous sections, Figure 2-8 shows a detailed example of an active EEL block containing several variable instances. The following variables are declared in this example:\n\n- ID 0x01 with size = 0x04,\n- ID 0x02 with size = 0x01,\n- ID 0x03 is defined but not written here,\n- ID 0x04 with size = 0x02.\n\nThe variables have been written in the sequence ID 0x01 → ID 0x04 → ID 0x02. In this example, the variable with ID 0x03 has not been written yet.\n\n\nChapter 3 EEL Operation\n\nThis chapter introduces the operation of the Tiny EEL. Thereby, the focus is put on the concepts and flows required for a proper usage of the library. The exact specification of the API can be found in Chapter 4.\n\n3.1 Functions and Commands\n\nFor a better understanding of the flows and mechanisms required for an EEL usage, the basic functions of the Tiny EEL are introduced in the following. The API of the Tiny EEL is thereby on the one hand based on functions used to manage the operation of the library itself. On the other hand it offers so-called commands to access and control the content of the EEL pool and the EEL variables.\n\n3.1.1 EEL Functions\n\nThe following functions are provided to control the Tiny EEL:\n\n- **EEL_Init**: This function is used to initialize the internal data structures of the Tiny EEL. It is mandatory to call EEL_Init before any utilization of the library.\n- **EEL_Open**: EEL_Open activates the library operation.\n- **EEL_Close**: The library can be deactivated again via EEL_Close.\n- **EEL_Execute**: By means of the EEL_Execute function, the user can issue commands to access and manage the EEL variables. It is one of the main functions for utilizing the EEL. However, please note that issued commands are not completed directly but rather require to be processed with calls to EEL_Handler.\n- **EEL_Handler**: The EEL_Handler needs to be called regularly to drive pending commands and observe their progress.\n- **EEL_GetDriverStatus**: This function opens a way to check the internal status of the EEL driver before placing a request.\n- **EEL_GetSpace**: By means of this function, the developer can check the remaining free space in the current active block, thereby aiding the decision when a refresh (i.e. transition to a new active block) is required.\n- **EEL_GetVersionString**: This function provides library version information at runtime.\n\n3.1.2 EEL Commands\n\nCommands are used to manage the EEL pool and to access the EEL variable set. The actual EEL variable set is defined by the designer at compile time and can be configured in terms of number and size of variables.\n\nCommands are initiated via EEL_Execute and processed stepwise by consecutive calls of EEL_Handler. This way, the execution of each EEL command is separated into several steps processed by an EEL-internal state machine. The following commands are offered by the Tiny EEL:\n\n**Pool-oriented Commands**\n\n- **Startup**: The startup command analyses the current EEL pool and needs to be executed before EEL variables can be accessed.\n- **Shutdown**: Shutdown is the counterpart to the startup command and required for a controlled ending of the EEL operation.\n- **Format**: By means of the format command, an initial empty EEL pool structure is created. All existing EEL variable content is lost during this step.\n• Refresh: The refresh command triggers the activation of a new EEL block. Thereby the old active block is invalidated and all current variable instances are copied to the new block. A refresh needs to be performed whenever the current active block does not provide enough space to update a variable via a write command.\n\n• Verify: The verify command provides a way to check for full data retention of the flash cells in the active EEL block.\n\nVariable-oriented Commands\n\n• Write: The write command is used to update the content of an EEL variable.\n• Read: The read command provides read access to EEL variables.\n\n3.1.3 Request-Response-oriented Dialog\n\nThe Tiny EEL utilizes a request-response architecture to initiate the commands. This means any \"requester\" (any tasks in the user application) has to prepare a request variable as a kind of \"request form sheet\" and pass it by reference to the Tiny EEL driver using its EEL_Execute function. The Tiny EEL interprets the content of the request variable, checks its plausibility and initiates the execution. The feedback is reflected immediately to the requester via the status member of the same request variable. The completion of an accepted request/command is done by calling EEL_Handler periodically as long the request remains \"busy\".\n\n\n\nThe biggest advantage of the request-response architecture is the constant and narrow parameter interface. It allows steady parameter passing and is therefore independent from the used compiler and its memory models. An additional advantage is the possibility to isolate the dialog between several requesters and the driver in multi-tasking systems. Thereby, multiple request variables can be used from different tasks.\n\nThe details on the request variable structure and its members are given later in Section 4.1.5. Please also note that not all structure members are required for all commands. The individual command descriptions in Section 4.3 provide the corresponding detailed information.\n\n3.1.4 Handler-oriented Command Execution\n\nIn order to satisfy the operation in concurrent or distributed systems, the command execution is divided into two steps:\n\n1. Initiation of the command execution using EEL_Execute.\n2. Processing of the requested command state by state using EEL_Handler.\n\nThis approach comes with one important advantage: Command processing can be done centrally at one place in the target system (normally the idle-loop or the scheduler loop), while the status of the requests can be polled locally within the requesting tasks.\n\nPlease note that EEL_Execute only initiates the command execution and returns immediately with the request-status “busy” after execution of the first internal state (or an error in case the request cannot be accepted). The further command execution is performed in the EEL_Handler, where the internal sequences of the command are executed state by state. Together with the background-operation feature of the Tiny FDL, this enables to design complex applications utilizing the computational resources of the processor efficiently, i.e. to perform other tasks on the CPU while flash operations are running in parallel.\n\nFigure 3-2: Schematic illustration of the polling operation mode\nThis way of controlling the EEL is also referred to as polling mode. Figure 3-2 illustrates the schematic flow of this operation mode.\n\n**Note 1:**\nWhile no command is being processed, EEL_Handler consumes a few CPU cycles only. The polling mode avoids blocking by the EEL.\n\n**Note 2:**\nIn order to minimize the code size and resource consumption of the library, the Tiny EEL only supports the polling mode. Other operation modes like the enforced and timeout mode known from the RL78 EEL Type T01 have been omitted in the Tiny EEL.\n\n**Note 3:**\nAs the first state of the EEL command is already executed by the call of EEL_Execute, there are commands which can finish their operation immediately after EEL_Execute and do not require to call the EEL_Handler. Please see the individual command description for details.\n\nFrom perspective of the user application, the safest way to deal with the execution of commands is to always follow the above mentioned procedure and check the status after each call of EEL_Execute and EEL_Handler.\n\n### 3.2 Basic Workflow\n\nThe basic workflow for utilizing the Tiny EEL is shown in Figure 3-3. The internal states of the EEL are depicted in ellipses with the state name printed in bold letters. Along with the internal state, the driver status is given, which can be retrieved any time via the EEL_GetDriverStatus function. This driver status can be one of the following:\n\n- **PASSIVE:** The EEL is not started up completely. It is not possible to issue EEL commands (except startup and format in opened state).\n- **BUSY:** The EEL is currently processing a command and cannot accept a new one for execution.\n- **IDLE:** The EEL has currently no running tasks and is accepting new commands.\n\nStates and transitions depicted in bold lines indicate normal library operation, while the states and transitions in thin lines indicate exceptional operation. The detailed flow is described in the following.\n\nAfter powering up the device, the Tiny FDL needs to be initialized and opened. This must be done before any EEL function is executed. EEL_Open and EEL_Close can then be used to activate and deactivate the EEL, i.e. to switch between *closed* and *opened* state.\n\nWhen the user application is started for the very first time, it is usually necessary to format the EEL pool before any EEL variable can be written. In order not to process random data during startup, it is necessary to perform this initial format from the *opened* state.\n\nIf the EEL pool contains valid data already, it is necessary to perform a startup command from the *opened* state, which processes the current pool structure and builds up internal lookup tables for fast read/write access to the EEL variables. Thereby, the library is driven into the *started-up* state—in case no error occurs.\n\nFrom the *started-up* state, the commands for usual operation can be executed (i.e. read, write, refresh and verify).\n\nProblems during startup can either indicate an inconsistent pool (e.g. not formatted before first usage) or an exhaustive pool (i.e. there are not sufficient non-excluded blocks left for library operation). While the library returns into the *opened* state in the former case, it moves to the *exhausted* state in the latter. From the *exhausted* state, only read and verify commands can be executed. Writing and refreshing is not possible.\n\nPlease note that an exhausted-pool scenario can also occur during a refresh command. Therefore, a transition from the *full-access execution* state to the *exhausted* state is possible.\n**Note 1:**\nFigure 3-3 shows only the basic workflow. Few other transitions are possible and not blocked by the EEL, however the developer is strongly advised to use only the depicted transitions as long as there is no urgent reason to deviate from the proposed flow. Other possible state transitions are listed in the following:\n\n- **EEL_Close** and **EEL_Init** can be called from every state. Please note however, that this interrupts any EEL processing and can lead to unpredictable behavior.\n\n- The **format** command can be triggered also from the **started-up** state. However, the library will always return to the opened state after completion of the command.\n\n- The **startup** command can be triggered also from the **started-up** state. The library will perform a complete startup procedure and then return to the **started-up** state (as long as no error occurs). During normal operation however, such processing is not meaningful.\n\n- A power-off transition can happen in any state and leads to state “not powered”.\n\n---\n\n1 The FDL needs to be initialized and opened before the EEL can operate.\n\n2 The shutdown command only has a single state and does not require **EEL_Handler** calls for execution.\n• When the Tiny EEL is busy, the library cannot accept new commands and a request will be terminated with status \"rejected\".\n\nNote 2:\nOnce the format command is started, it must be finished before the Tiny EEL can be used again.\nChapter 4 Application Programming Interface (API)\n\nThis chapter provides the formal description of the application programming interface of the EEPROM Emulation Library Type T02 (Tiny EEL). It is strongly advised to read and understand the previous chapters presenting the concepts and structures of the library before continuing with the API details.\n\n4.1 Data Types\n\nThis section describes all data definitions used and offered by the EEL. In order to reduce the probability of type mismatches in the user application, please make strict usage of the provided types and avoid using standard data types instead.\n\n**C API**\n\nAll types are defined in the header file eel_types.h, which is part of the library installation package. It contains simple type definitions as well as library specific enumeration types and structs.\n\n**Assembler API**\n\nWhile there are no structs and enumeration types available in assembler, only constant definitions according to the C enumeration types are provided in eel_types.inc. Please derive the order and size of struct members from the C type definitions.\n\n4.1.1 Library-specific Simple-Type Definitions\n\n<table>\n<thead>\n<tr>\n<th>Type definition:</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>typedef unsigned char eel_u08;</td>\n</tr>\n<tr>\n<td>typedef unsigned int eel_u16;</td>\n</tr>\n<tr>\n<td>typedef unsigned long int eel_u32;</td>\n</tr>\n</tbody>\n</table>\n\n**Description:** These simple types are used throughout the complete library API for passing of integer parameters.\n### 4.1.2 eel_command_t\n\n**Type definition:**\n\n```c\ntypedef enum\n{\n EEL_CMD_UNDEFINED = (0x00 | 0x00),\n EEL_CMD_STARTUP = (0x00 | 0x01),\n EEL_CMD_WRITE = (0x00 | 0x02),\n EEL_CMD_READ = (0x00 | 0x03),\n EEL_CMD_REFRESH = (0x00 | 0x04),\n EEL_CMD_VERIFY = (0x00 | 0x05),\n EEL_CMD_FORMAT = (0x00 | 0x06),\n EEL_CMD_SHUTDOWN = (0x00 | 0x07)\n} eel_command_t;\n```\n\n**Description:** The enumeration type eel_command_t defines all allowed codes used to specify library commands. This type is used within the structure eel_request_t (see Section 4.1.5) in order to specify which command shall be executed via the function EEL_Execute. A detailed description of each command can be found in Section 4.3.\n\nPlease note that due to the fact that the library has been implemented in Assembler, it is mandatory that the enumeration type eel_command_t has a size of exactly 1 byte.\n\n**Note:**\nThe GNU compiler uses 16-bit enumeration types by default. Therefore, for GNU compiler, the declaration of the enumeration type has to be extended with an attribute in order to be compiled to 1 byte: `__attribute__((__packed__))`.\n\n**Member / Value:**\n\n<table>\n<thead>\n<tr>\n<th>Member / Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_CMD_UNDEFINED</td>\n<td>undefined command</td>\n</tr>\n<tr>\n<td>EEL_CMD_STARTUP</td>\n<td>plausibility check of the EEL data and driver</td>\n</tr>\n<tr>\n<td>EEL_CMD_WRITE</td>\n<td>creates a new instance of an EEL variable</td>\n</tr>\n<tr>\n<td>EEL_CMD_READ</td>\n<td>reads latest instance of an EEL variable</td>\n</tr>\n<tr>\n<td>EEL_CMD_REFRESH</td>\n<td>copy the latest instance of each variable into a new</td>\n</tr>\n<tr>\n<td></td>\n<td>active block</td>\n</tr>\n<tr>\n<td>EEL_CMD_VERIFY</td>\n<td>verify the active block byte by byte to check for full data retention</td>\n</tr>\n<tr>\n<td>EEL_CMD_FORMAT</td>\n<td>format the EEL pool, all instances are lost</td>\n</tr>\n<tr>\n<td>EEL_CMD_SHUTDOWN</td>\n<td>deactivates the EEL and drives it into a secure state</td>\n</tr>\n</tbody>\n</table>\n4.1.3 eel_driver_status_t\n\nType definition:\n\n```c\ntypedef enum {\n EEL_DRIVER_PASSIVE = (0x00 | 0x00),\n EEL_DRIVER_IDLE = (0x30 | 0x01),\n EEL_DRIVER_BUSY = (0x30 | 0x02)\n} eel_driver_status_t;\n```\n\nDescription: The enumeration type eel_driver_status_t defines all codes of available driver operation statuses. This type is used in the function EEL_GetDriverStatus (see Section 4.2.6) providing access to the driver status of the library.\n\nPlease note that due to the fact that the library has been implemented in Assembler, it is mandatory that the enumeration type eel_driver_status_t has a size of exactly 1 byte.\n\nNote: The GNU compiler uses 16-bit enumeration types by default. Therefore, for GNU compiler, the declaration of the enumeration type has to be extended with an attribute in order to be compiled to 1 byte: `__attribute__((__packed__))`.\n\nMember / Value:\n\n<table>\n<thead>\n<tr>\n<th>Member / Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_DRIVER_PASSIVE</td>\n<td>library is not yet started up completely</td>\n</tr>\n<tr>\n<td>EEL_DRIVER_IDLE</td>\n<td>no command is being executed, new commands can be accepted</td>\n</tr>\n<tr>\n<td>EEL_DRIVER_BUSY</td>\n<td>a command is just being executed, new commands cannot be accepted</td>\n</tr>\n</tbody>\n</table>\n4.1.4 eel_status_t\n\nType definition:\n\n```c\ntypedef enum\n{\n EEL_OK = (0x00 | 0x00),\n EEL_BUSY = (0x00 | 0x01),\n EEL_ERR_CONFIGURATION = (0x80 | 0x02),\n EEL_ERR_INITIALIZATION = (0x80 | 0x03),\n EEL_ERR_ACCESS_LOCKED = (0x80 | 0x04),\n EEL_ERR_PARAMETER = (0x80 | 0x05),\n EEL_ERR_VERIFY = (0x80 | 0x06),\n EEL_ERR_REJECTED = (0x80 | 0x07),\n EEL_ERR_NO_INSTANCE = (0x80 | 0x08),\n EEL_ERR_POOL_FULL = (0x80 | 0x09),\n EEL_ERR_POOL_INCONSISTENT = (0x80 | 0x0A),\n EEL_ERR_POOL_EXHAUSTED = (0x80 | 0x0B),\n EEL_ERR_INTERNAL = (0x80 | 0x0C)\n} eel_status_t;\n```\n\nDescription: The enumeration type eel_status_t defines all codes of function and command statuses and errors. On the one hand, it is used as return type of the functions EEL_Init (see Section 0) and EEL_GetSpace (see Section 4.2.7). On the other hand, it is used within the structure eel_request_t (see Section 4.1.5) in order to capture the processing of currently running command. Thereby, the possible error codes are command specific and described in detail in Section 4.3 along with the commands. Please note that due to the fact that the library has been implemented in Assembler, it is mandatory that the enumeration type eel_status_t has a size of exactly 1 byte.\n\nNote: The GNU compiler uses 16-bit enumeration types by default. Therefore, for GNU compiler, the declaration of the enumeration type has to be extended with an attribute in order to be compiled to 1 byte: “__attribute__((__packed__))”.\n<table>\n<thead>\n<tr>\n<th>Member / Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_OK</td>\n<td>no error occurred</td>\n</tr>\n<tr>\n<td>EEL_BUSY</td>\n<td>request is under processing</td>\n</tr>\n<tr>\n<td>EEL_ERR_CONFIGURATION</td>\n<td>bad FDL/EEL configuration or combination</td>\n</tr>\n<tr>\n<td>EEL_ERR_INITIALIZATION</td>\n<td>call to EEL_Init(), EEL_Open() missing</td>\n</tr>\n<tr>\n<td>EEL_ERR_ACCESS_LOCKED</td>\n<td>execution of startup command missing</td>\n</tr>\n<tr>\n<td>EEL_ERR_PARAMETER</td>\n<td>wrong parameter (wrong command or identifier)</td>\n</tr>\n<tr>\n<td>EEL_ERR_VERIFY</td>\n<td>at least one byte in the active block does not provide the full data retention</td>\n</tr>\n<tr>\n<td>EEL_ERR_REJECTED</td>\n<td>request rejected as another request is already being processed</td>\n</tr>\n<tr>\n<td>EEL_ERR_NO_INSTANCE</td>\n<td>no instance found (variable never written)</td>\n</tr>\n<tr>\n<td>EEL_ERR_POOL_FULL</td>\n<td>not enough space for writing data</td>\n</tr>\n<tr>\n<td>EEL_ERR_POOL_INCONSISTENT</td>\n<td>EEL pool is inconsistent</td>\n</tr>\n<tr>\n<td>EEL_ERR_POOL_EXHAUSTED</td>\n<td>EEL pool is too small for write/refresh operation</td>\n</tr>\n<tr>\n<td>EEL_ERRINTERNAL</td>\n<td>internal error (should never occur), please contact support</td>\n</tr>\n</tbody>\n</table>\n4.1.5 eel_request_t\n\nType definition:\n\n```c\ntypedef struct {\n __near eel_u08* address_pu08;\n eel_u08 identifier_u08;\n eel_command_t command_enu;\n eel_status_t status_enu;\n} eel_request_t;\n```\n\nDescription: The structured type eel_request_t defines the structure of EEL request variables. It is the central type for the request-response-oriented dialog for the execution of commands (see Section 3.1.3). Not every element of this structure is required for each command. However, all members of the request variable must be initialized once before usage. Please refer to Section 4.3 for a more detailed description and the command-specific usage of the structure elements.\n\nPlease note that any variable of the type eel_request_t needs to be located at an even address.\n\nNote: The GNU compiler does not require the \"__near\" keyword to declare near pointers. All pointers are near by default as long as the \"__far\" keyword is not used.\n\nMember / Value:\n\n<table>\n<thead>\n<tr>\n<th>Member / Value</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>address_pu08</td>\n<td>source/destination RAM-address</td>\n</tr>\n<tr>\n<td>identifier_u08</td>\n<td>variable identifier</td>\n</tr>\n<tr>\n<td>command_enu</td>\n<td>command to be processed (see Section 4.1.2)</td>\n</tr>\n<tr>\n<td>status_enu</td>\n<td>status/error code after command execution (see Section 4.1.4)</td>\n</tr>\n</tbody>\n</table>\n4.1.6 eel_descriptor\n\nDefinition:\n\n```c\n__far const eel_u08 eel_descriptor[EEL_VAR_NO+2] =\n[\n (eel_u08)(EEL_VAR_NO), /* variable count */ \\n (eel_u08)(sizeof(type_A)), /* id = 1 */ \\n (eel_u08)(sizeof(type_B)), /* id = 2 */ \\n ... \\n (eel_u08)(sizeof(type_Z)), /* id = EEL_VAR_NO */ \\n (eel_u08)(0x00), /* zero terminator */ \\n];\n```\n\nDescription: The variable eel_descriptor is actually not a type. Nevertheless, it is included in the list of data types here, because its definition is mandatory for the operation of the EEL. The eel_descriptor specifies the EEL variable set by means of a constant byte array.\n\nAn exemplary descriptor can be found in eel_descriptor.c and needs to be adapted according to the application requirements. The first element of the array represents the number of defined variables. This element is followed by the size of each variable which may be between 1 and 255 bytes. Thereby, the index within the array matches the corresponding variable ID. The variable list needs to be zero terminated in the last element.\n\nFurther information on how to configure the variable set can be found in Section 5.4.3.\n4.2 Functions\n\nDue to the request-oriented interface of the Tiny EEL, the functional interface is very narrow. Beside the initialization and some administrative functions, the access to the EEL pool concentrates on two functions only: EEL_Execute and EEL_Handler.\n\nAll Tiny EEL interface functions are prototyped in the header file eel.h.\n\nNote:\nThe register naming conventions defined by the GNU Compiler differs from the standard one provided by CA78K0R. The mapping of registers used by this library is as follows:\n\nTable 4-1: Register naming conventions (GNU Compiler vs. standard)\n\n<table>\n<thead>\n<tr>\n<th>CA78K0R</th>\n<th>GNU Compiler</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>X (Register bank 1)</td>\n<td>R8</td>\n</tr>\n<tr>\n<td>A (Register bank 1)</td>\n<td>R9</td>\n</tr>\n<tr>\n<td>C (Register bank 1)</td>\n<td>R10</td>\n</tr>\n<tr>\n<td>B (Register bank 1)</td>\n<td>R11</td>\n</tr>\n</tbody>\n</table>\n\n4.2.1 EEL_Init\n\nOutline: EEL_Init has to be called before any EEL usage. The function initializes all internal data and variables and performs a plausibility check of the configuration.\n\nInterface: C Interface for CA78K0R Compiler\n\n```c\neel_status_t __far EEL_Init(void);\n```\n\nC Interface for IAR V1.xx Compiler\n\n```c\n__far_func eel_status_t EEL_Init(void);\n```\n\nC Interface for IAR V2.xx Compiler\n\n```c\n__far_func eel_status_t EEL_Init(void);\n```\n\nC Interface for GNU Compiler\n\n```c\neel_status_t EEL_Init(void) __attribute__ ((section (\"EEL_CODE\")));\n```\n\nC Interface for CC-RL Compiler\n\n```c\neel_status_t __far EEL_Init(void);\n```\n\nASM function label\n\n```c\nEEL_Init\n```\nArguments: **Parameters**\n\nnone\n\nReturn value\n\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Passed via</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>CA78K0R</td>\n</tr>\n<tr>\n<td>eel_status_t</td>\n<td>C</td>\n</tr>\n</tbody>\n</table>\n\nStatus of the function execution. Can be one of the following:\n\n- **EEL_OK**: initialization done without problems\n- **EEL_ERR_CONFIGURATION**: pool configuration error (EEL descriptor not plausible) or wrong FDL linked to the project\n\nDestructed registers\n\n<table>\n<thead>\n<tr>\n<th>Tool chain</th>\n<th>Destructed registers</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CA78K0R</td>\n<td>none</td>\n</tr>\n<tr>\n<td>IAR V1.xx</td>\n<td>none</td>\n</tr>\n<tr>\n<td>IAR V2.xx</td>\n<td>X, BC, D, HL</td>\n</tr>\n<tr>\n<td>GNU</td>\n<td>none</td>\n</tr>\n<tr>\n<td>CC-RL</td>\n<td>X, BC, D, HL</td>\n</tr>\n</tbody>\n</table>\n\nPre-conditions:\nThe Tiny FDL must be initialized and opened successfully before EEL_Init can be executed.\n\nPost-conditions:\nnone\n\nDescription:\nEEL_Init has to be called before any EEL usage. The function initializes all internal data structures and variables and performs a plausibility check of the configuration (EEL descriptor).\n\nFirst, the signature of the used FDL is checked to ensure that the right FDL (Type T02) is the counterpart of the EEL.\n\nAfter that, the plausibility of the EEL descriptor is checked by this function. Thereby the following properties are evaluated:\n\n- the number of defined EEL variables (at least 1, maximum 64),\n- the variable count matches the number of entries in the eel_descriptor array (see eel_descriptor.c),\n- the zero-termination of eel_descriptor array (see eel_descriptor.c), and\n- the total size of all defined variables is small enough to keep library operational (i.e. when all variables are instantiated once in the active block, the remaining free space is sufficient to write the largest variable at least once).\n\nPlease note that the plausibility checks only aim at checks for operability. Still, the developer can create configurations which are not efficient (e.g. require to trigger frequent refreshes in case of very large EEL variable sets).\nExample:\n\n```c\neel_status_t my_eel_status;\nmy_eel_status = EEL_Init();\nif (my_eel_status != EEL_OK)\n{\n MyErrorHandler();\n}\n```\n4.2.2 EEL_Open\n\nOutline: This function opens the EEL logically.\n\nInterface: C Interface for CA78K0R Compiler\n\n```c\nvoid __far EEL_Open(void);\n```\n\nC Interface for IAR V1.xx Compiler\n\n```c\n__far_func void EEL_Open(void);\n```\n\nC Interface for IAR V2.xx Compiler\n\n```c\n__far_func void EEL_Open(void);\n```\n\nC Interface for GNU Compiler\n\n```c\nvoid EEL_Open(void) __attribute__ ((section (\"EEL_CODE\")));\n```\n\nC Interface for CC-RL Compiler\n\n```c\nvoid __far EEL_Open(void);\n```\n\nASM function label\n\n```c\nEEL_Open\n```\n\nArguments: Parameters\n\nnone\n\nReturn value\n\nnone\n\nDestructed registers\n\nnone\n\nPre-conditions: EEL_Init has to be executed successfully before. (This implies that the Tiny FDL has been initialized and opened beforehand.)\n\nPost-conditions: none\nDescription: By means of the EEL_Open function, the Tiny EEL can be opened logically for usage. Please note that this does not activate the data flash. Enabling the data flash has to be done via the Tiny FDL by the corresponding FDL_Open function.\n\nExample:\n\n```c\nEEL_Open();\n```\n4.2.3 EEL_Close\n\nOutline: This function closes the EEL logically.\n\nInterface: **C Interface for CA78K0R Compiler**\n\n```c\nvoid __far EEL_Close(void);\n```\n\n**C Interface for IAR V1.xx Compiler**\n\n```c\n__far_func void EEL_Close(void);\n```\n\n**C Interface for IAR V2.xx Compiler**\n\n```c\n__far_func void EEL_Close(void);\n```\n\n**C Interface for GNU Compiler**\n\n```c\nvoid EEL_Close(void) __attribute__ ((section (\"EEL_CODE\")));\n```\n\n**C Interface for CC-RL Compiler**\n\n```c\nvoid __far EEL_Close(void);\n```\n\n**ASM function label**\n\n```c\nEEL_Close\n```\n\nArguments: **Parameters**\n\nnone\n\n**Return value**\n\nnone\n\n**Destructed registers**\n\n<table>\n<thead>\n<tr>\n<th>Tool chain</th>\n<th>Destructed registers</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CA78K0R</td>\n<td>none</td>\n</tr>\n<tr>\n<td>IAR V1.xx</td>\n<td>none</td>\n</tr>\n<tr>\n<td>IAR V2.xx</td>\n<td>A</td>\n</tr>\n<tr>\n<td>GNU</td>\n<td>none</td>\n</tr>\n<tr>\n<td>CC-RL</td>\n<td>A</td>\n</tr>\n</tbody>\n</table>\nPre- none\nconditions:\n\nPost- none\nconditions:\n\nDescription: By means of the EEL_Close function, the Tiny EEL can be closed logically. Please note that this does not deactivate the data flash. Disabling the data flash has to be done via the Tiny FDL by the corresponding FDL_Close function.\n\nExample:\n\n```c\nEEL_Close();\n```\n### 4.2.4 EEL_Execute\n\n**Outline:** This function initiates the execution of an EEL command.\n\n**Interface:**\n\n**C Interface for CA78K0R Compiler**\n\n```c\nvoid __far EEL_Execute(__near eel_request_t* request_pstr);\n```\n\n**C Interface for IAR V1.xx Compiler**\n\n```c\n__far_func void EEL_Execute(__near eel_request_t __near* request_pstr);\n```\n\n**C Interface for IAR V2.xx Compiler**\n\n```c\n__far_func void EEL_Execute(eel_request_t __near * request_pstr);\n```\n\n**C Interface for GNU Compiler**\n\n```c\nvoid EEL_Execute(eel_request_t* request_pstr)\n__attribute__ ((section (\"EEL_CODE\")));\n```\n\n**C Interface for CC-RL Compiler**\n\n```c\nvoid __far EEL_Execute(__near eel_request_t* request_pstr);\n```\n\n**ASM function label**\n\n```c\nEEL_Execute\n```\n\n**Arguments:**\n\n<table>\n<thead>\n<tr>\n<th>Argument</th>\n<th>Access</th>\n<th>CA78K0R</th>\n<th>IAR V1.xx</th>\n<th>IAR V2.xx</th>\n<th>GNU</th>\n<th>CC-RL</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>request_pstr</td>\n<td>rw</td>\n<td>AX</td>\n<td>AX</td>\n<td>AX</td>\n<td></td>\n<td>AX</td>\n</tr>\n</tbody>\n</table>\n\nThis argument points to a request structure defining the command the EEL should execute. The request structure is used for bidirectional information exchange between EEL and application during command execution.\n\nA detailed description of the eel_request_t structure can be found in Section 4.1.5.\n\n**Return value**\n\nnone\n### Destructed registers\n\n<table>\n<thead>\n<tr>\n<th>Tool chain</th>\n<th>Destructed registers</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CA78K0R</td>\n<td>AX</td>\n</tr>\n<tr>\n<td>IAR V1.xx</td>\n<td>AX</td>\n</tr>\n<tr>\n<td>IAR V2.xx</td>\n<td>AX, BC, DE, HL</td>\n</tr>\n<tr>\n<td>GNU</td>\n<td>none</td>\n</tr>\n<tr>\n<td>CC-RL</td>\n<td>AX, BC, DE, HL</td>\n</tr>\n</tbody>\n</table>\n\n**Pre-conditions:**\n- EEL_Init must be executed successfully before.\n- EEL_Open must be executed before.\n\n**Post-conditions:**\n- none\n\n**Description:** By means of the EEL_Execute function, the execution of EEL commands can be initiated. The type and parameters of the command to be executed are collected in the request structure pointed to by request_pstr (see also Section 4.1.5). The underlying request-response concept is introduced in Section 3.1.3.\n\nA detailed description of all available commands can be found in Section 4.3. Please note that the meaning of the different request structure elements depends on the command. Before execution, the request structure is checked for plausibility. However, the error codes (returned as a member of the request structure) are command-specific as well. Please have a look at the command description.\n\nEEL_Execute only initiates the command execution. Please be aware that it is necessary for (almost) all commands to complete the command execution by EEL_Handler calls as introduced in Section 3.1.4. However, depending on the command it is possible that the EEL_Handler is executed implicitly by EEL_Execute. Therefore, commands may finish directly after the EEL_Execute call, indicated by an update of the status member of the request variable.\n\nOne advantage of the request-response oriented command execution is that multiple independent request structures can be used. Thereby, different commands can be prepared and monitored in parallel, although a real parallel execution is not possible. Especially in case of operating systems, tasks can use their own request variables in order to decouple the EEL accesses between the tasks.\n\n**Note 1:**\nAlthough there are commands that do not require all request structure elements to be specified, the whole structure needs to be initialized before calling EEL_Execute. Otherwise, a RAM parity/ECC error may cause a reset of the device. For details, please refer to the document “User’s Manual: Hardware” of your RL78 product.\n\n**Note 2:**\nThe request structure used for execution has to be word-aligned, i.e. located at an even memory address.\n\n**Example:** Code examples for the execution of commands can be found in Section 4.3.8.\n4.2.5 EEL_Handler\n\nOutline: This function needs to be called in order to drive pending commands and observe their progress.\n\nInterface:\n\nC Interface for CA78K0R Compiler\n\n```c\nvoid __far EEL_Handler(void);\n```\n\nC Interface for IAR V1.xx Compiler\n\n```c\n__far_func void EEL_Handler(void);\n```\n\nC Interface for IAR V2.xx Compiler\n\n```c\n__far_func void EEL_Handler(void);\n```\n\nC Interface for GNU Compiler\n\n```c\nvoid EEL_Handler(void) __attribute__ ((section (\"EEL_CODE\")));\n```\n\nC Interface for CC-RL Compiler\n\n```c\nvoid __far EEL_Handler(void);\n```\n\nASM function label\n\nEEL_Handler\n\nArguments:\n\nParameters\nnone\n\nReturn value\nnone\n\nDestructed registers\n\n<table>\n<thead>\n<tr>\n<th>Tool chain</th>\n<th>Destructed registers</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CA78K0R</td>\n<td>none</td>\n</tr>\n<tr>\n<td>IAR V1.xx</td>\n<td>none</td>\n</tr>\n<tr>\n<td>IAR V2.xx</td>\n<td>AX, BC, DE, HL</td>\n</tr>\n<tr>\n<td>GNU</td>\n<td>none</td>\n</tr>\n<tr>\n<td>CC-RL</td>\n<td>AX, BC, DE, HL</td>\n</tr>\n</tbody>\n</table>\nPre-conditions: EEL_Init must be executed successfully before.\n\nPost-conditions: The status of a pending EEL or FDL command may be updated, i.e. the status_enu member of the corresponding request structure is written.\n\nDescription: The function EEL_Handler needs to be called regularly in order to drive pending commands and observe their progress. Thereby, the command execution is performed state by state. When a command execution is finished, the request status variable (structural element status_enu of eel_request_t) is updated and contains the status/error code of the corresponding command execution. Please have a look at Section 3.1.4 for a more detailed description of the principles of the handler-oriented command execution.\n\nPlease be aware that the EEL_Handler may implicitly call the FDL_Handler and therefore finish pending FDL commands. However, the EEL_Handler shall not be used instead of the FDL_Handler to finish FDL commands, as it is not guaranteed that the EEL_Handler invokes the FDL_Handler always.\n\nNote: When no command is being processed, EEL_Handler consumes a few CPU cycles only.\n\nExample:\n\n```c\nwhile (true) {\n EEL_Handler();\n User_Task_A();\n User_Task_B();\n User_Task_C();\n User_Task_D();\n}\n```\n4.2.6 EEL_GetDriverStatus\n\nOutline: This function opens a way to check the internal status of the EEL driver before placing a request.\n\nInterface: C Interface for CA78K0R Compiler\n\n```c\nvoid __far EEL_GetDriverStatus(__near eel_driver_status_t* eel_driver_status_penu);\n```\n\nC Interface for IAR V1.xx Compiler\n\n```c\n__far_func void EEL_GetDriverStatus(__near eel_driver_status_t __near* eel_driver_status_penu);\n```\n\nC Interface for IAR V2.xx Compiler\n\n```c\n__far_func void EEL_GetDriverStatus(eel_driver_status_t __near* eel_driver_status_penu);\n```\n\nC Interface for GNU Compiler\n\n```c\nvoid EEL_GetDriverStatus(eel_driver_status_t* eel_driver_status_penu)\n__attribute__ ((section (\"EEL_CODE\")));\n```\n\nC Interface for CC-RL Compiler\n\n```c\nvoid __far EEL_GetDriverStatus(__near eel_driver_status_t* eel_driver_status_penu);\n```\n\nASM function label\n\n```\nEEL_GetDriverStatus\n```\n\nArguments: Parameters\n\n<table>\n<thead>\n<tr>\n<th>Argument</th>\n<th>Access</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>eel_driver_status_penu</td>\n<td>w</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Passed via</th>\n<th>CA78K0R</th>\n<th>IAR V1.xx</th>\n<th>IAR V2.xx</th>\n<th>GNU</th>\n<th>CC-RL</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>eel_driver_status_t* (near)</td>\n<td>AX</td>\n<td>AX</td>\n<td>AX</td>\n<td>stack</td>\n<td>AX</td>\n<td></td>\n</tr>\n</tbody>\n</table>\n\nPointer to the driver status variable which is updated by the EEL_GetDriverStatus function, which is one of the following:\n\n- EEL_DRIVER_PASSIVE: driver passive, EEL not started up correctly\n- EEL_DRIVER_BUSY: driver busy, EEL cannot accept new commands\n- EEL_DRIVER_IDLE: driver idle, EEL awaits new commands\n\nThe eel_driver_status_t enumeration type is defined in Section 0.\nReturn value\n\nnone\n\nDestructed registers\n\n<table>\n<thead>\n<tr>\n<th>Tool chain</th>\n<th>Destructed registers</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CA78K0R</td>\n<td>AX</td>\n</tr>\n<tr>\n<td>IAR V1.xx</td>\n<td>AX</td>\n</tr>\n<tr>\n<td>IAR V2.xx</td>\n<td>A,BC,D,HL</td>\n</tr>\n<tr>\n<td>GNU</td>\n<td>none</td>\n</tr>\n<tr>\n<td>CC-RL</td>\n<td>A,BC,D,HL</td>\n</tr>\n</tbody>\n</table>\n\nPre-conditions:\n\nnone\n\nPost-conditions:\n\nDescription: The EEL_GetDriverStatus function opens a way to check the internal status of the EEL driver before placing a request. The returned status can be one of the following:\n\n- **EEL_DRIVER_PASSIVE:** The EEL is not started up completely. It is not possible to issue EEL commands (except startup and format when the library is initialized and opened). An access to the EEL data is not possible.\n\n- **EEL_DRIVER_BUSY:** The EEL is currently processing a command and cannot accept a new one for execution.\n\n- **EEL.Driver_IDLE:** The library has been initialized, opened and started up (see Section 4.3.1) successfully. The EEL has currently no running tasks and is accepting new commands.\n\nA more detailed correlation between driver status and the EEL workflow is given in Figure 3-3 (Section 3.2).\n\nExample:\n\n```c\neel_driver_status_t my_eel_driver_status;\n\nEEL_GetDriverStatus((__near eel_driver_status_t*)&my_eel_driver_status);\nif (my_eel_driver_status == EEL_DRIVER_PASSIVE)\n{\n /* initialize EEL and execute the STARTUP command */\n}\nelse\n{\n /* ensure that the EEL driver is idle before issuing request */\n while (my_eel_driver_status == EEL_DRIVER_BUSY)\n {\n EEL_Handler();\n EEL_GetDriverStatus((__near eel_driver_status_t*)&my_eel_driver_status);\n }\n}\n/* the user can place requests here */\n```\n4.2.7 EEL_GetSpace\n\nOutline: By means of this function, the developer can check the remaining free space in the current active block, thereby aiding the decision when a refresh (i.e. transition to a new active block) is required.\n\nInterface:\n\nC Interface for CA78K0R Compiler\n\n```c\neel_status_t __far EEL_GetSpace(__near eel_u16* space_pu16);\n```\n\nC Interface for IAR V1.xx Compiler\n\n```c\n__far_func eel_status_t EEL_GetSpace(__near eel_u16 __near* space_pu16);\n```\n\nC Interface for IAR V2.xx Compiler\n\n```c\n__far_func eel_status_t EEL_GetSpace(eel_u16 __near * space_pu16);\n```\n\nC Interface for GNU Compiler\n\n```c\neel_status_t EEL_GetSpace(eel_u16* space_pu16)\n __attribute__((section(\"EEL_CODE\")));\n```\n\nC Interface for CC-RL Compiler\n\n```c\neel_status_t __far EEL_GetSpace(__near eel_u16* space_pu16);\n```\n\nASM function label\n\n```c\nEEL_GetSpace\n```\n\nArguments: Parameters\n\n<table>\n<thead>\n<tr>\n<th>Argument</th>\n<th>Access</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>space_pu16</td>\n<td>w</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Passed via</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>eel_u16*</td>\n<td></td>\n</tr>\n<tr>\n<td>(near)</td>\n<td>CA78K0R</td>\n</tr>\n<tr>\n<td></td>\n<td>AX</td>\n</tr>\n</tbody>\n</table>\n\nAddress of the space information variable which is updated during function execution.\nReturn value\n\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Passed via</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td></td>\n<td>CA78K0R</td>\n</tr>\n<tr>\n<td>eel_status_t</td>\n<td>C</td>\n</tr>\n</tbody>\n</table>\n\nStatus/error code of the execution of EEL_GetSpace. Can be one of the following:\n\n- **EEL_OK**: space value has been computed correctly\n- **EEL_ERR_INITIALIZATION**: EEL not initialized, space cannot be computed\n- **EEL_ERR_ACCESS_LOCKED**: EEL has not been started up, space cannot be computed\n- **EEL_ERR_REJECTED**: an EEL command is running, space cannot be computed\n\nDestructed registers\n\n<table>\n<thead>\n<tr>\n<th>Tool chain</th>\n<th>Destructed registers</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>CA78K0R</td>\n<td>AX</td>\n</tr>\n<tr>\n<td>IAR V1.xx</td>\n<td>AX</td>\n</tr>\n<tr>\n<td>IAR V2.xx</td>\n<td>X,C,HL</td>\n</tr>\n<tr>\n<td>GNU</td>\n<td>none</td>\n</tr>\n<tr>\n<td>CC-RL</td>\n<td>X,C,HL</td>\n</tr>\n</tbody>\n</table>\n\nPre-conditions:\nThe Tiny EEL must be initialized, opened and started up before the free space in the active block can be calculated.\n\nPost-conditions:\nnone\n\nDescription:\nBy means of this function, the developer can check the remaining free space in the current active block, thereby aiding the decision when a refresh (i.e. transition to a new active block) is required.\n\nIt is important to note that each instance of a variable consists of a reference entry of 2 bytes and the actual data section (see Section 2.3.3). Therefore, writing a variable of size \\( n \\) requires \\( n+2 \\) bytes of free space.\n\n**Note 1:**\nIn case the EEL pool is exhausted, the returned free space will always be 0.\n\n**Note 2:**\nIn case of an error return value, the space parameter is not changed.\n\n**Note 3:**\nIn case of interrupted write sequences (e.g. due to reset), the EEL_GetSpace function might return a free space of '0' after startup, indicating a necessary refresh.\nExample:\n\n```c\neel_status_t my_eel_status_enu;\neel_u16 my_eel_space_u16;\n\n/* execute the function */\nmy_eel_status_enu = EEL_GetSpace((__near eel_u16*)&my_eel_space_u16);\n\nif (my_eel_status_enu != EEL_OK)\n{\n MyErrorHandler();\n} else\n{\n /* my_eel_space_u16 is valid */\n /* do something */\n}\n```\n4.2.8 EEL_GetVersionString\n\nOutline: This function provides library version information at runtime.\n\nInterface: C Interface for CA78K0R Compiler\n\n```c\n__far eel_u08* __far EEL_GetVersionString(void);\n```\n\nC Interface for IAR V1.xx Compiler\n\n```c\n__far_func eel_u08 __far* EEL_GetVersionString(void);\n```\n\nC Interface for IAR V2.xx Compiler\n\n```c\n__far_func eel_u08 __far* EEL_GetVersionString(void);\n```\n\nC Interface for GNU Compiler\n\n```c\neel_u08 __far* EEL_GetVersionString(void)\n __attribute__ ((section (\"EEL_CODE\")));\n```\n\nC Interface for CC-RL Compiler\n\n```c\n__far eel_u08* __far EEL_GetVersionString(void);\n```\n\nASM function label\n\nEEL_GetVersionString\n\nArguments: Parameters\n\nnone\n\nReturn value\n\n<table>\n<thead>\n<tr>\n<th>Type</th>\n<th>Passed via</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>eel_u08* (far)</td>\n<td>CA78K0R</td>\n</tr>\n<tr>\n<td></td>\n<td>BC (low), DE (high)</td>\n</tr>\n</tbody>\n</table>\n\nFar (24 bit) address of the zero-terminated EEL version string.\n\nDestructed registers\n\nnone\nPre-conditions:\n\nPost-conditions:\n\nDescription: For version control at runtime the developer can use this function to find the starting character of the library version string (ASCII format).\n\nThe version string is a zero-terminated string constant that covers library-specific information and is based on the following structure: NMMMMTTTTCCCCCGVVV..V, where:\n\n- **N**: library type specifier (here ‘E’ for EEL)\n- **MMMM**: series name of microcontroller (here ‘RL78’)\n- **TTT**: type number (here ‘T02’)\n- **CCCCC**: compiler information\n - ‘Rxxy_’ for CA78K0R compiler version x.yy\n - ‘Ixyy_’ for IAR V1.xx compiler version x.yy\n - ‘Uxxyy’ for GNU compiler version xx.yy\n - ‘Lxyyz’ for CC-RL compiler version x.yy.0z\n\n- **G**: all memory models (here ‘G’ for general)\n- **VVV..V**: library version\n - ‘Vxyy’ for release version x.yy\n - ‘Exyyy’ for engineering version x.yyy\n\nExamples:\nThe version string of the Tiny EEL V1.00 for the CA78K0R compiler version 1.10 is:\n\"ERL78T02R110_GV100\"\nThe version string of the Tiny EEL V1.00 for the IAR V1.xx compiler version 1.20 is:\n\"ERL78T02I120_GV100\"\nThe version string of the Tiny EEL V1.01 for the GNU compiler version 13.02 is:\n\"ERL78T02U1302GV101\"\nThe version string of the Tiny EEL V1.01 for the CC-RL compiler version 1.23.04 is:\n\"ERL78T02L1234GV101\"\n\nExample:\n\n```c\n__far eel_u08* my_version_string_pu08;\nmy_version_string_pu08 = EEL_GetVersionString();\nPrintMyVersion(my_version_string_pu08);\n```\n4.3 Commands\n\nCommands are used to manage the EEL pool and to access the EEL variable set (see also Section 3.1.2). They are initiated via EEL_Execute and processed stepwise by consecutive calls of EEL_Handler. All EEL commands have to be initiated by passing a completed EEL-request structure (see Section 4.1.5) as parameter of EEL_Execute. As depicted in Figure 4-1, the three structure elements command_enu, identifier_u08 and address_pu08 need to be specified by the user while status_enu is set by the library.\n\nFigure 4-1: Schematic usage of the request variable (reprise of Figure 3-1)\n\nWhile the mandatory element command_enu specifies which command is to be executed, the usage of the elements identifier_u08 and address_pu08 depends on the command. Therefore these parameters and the possible return statuses are described individually for each command in the subsequent sections.\n\nAn overview of all available command codes including the usage of request variable members is listed in Table 4-2.\n\nTable 4-2: Command codes and usage of request variable members\n\n<table>\n<thead>\n<tr>\n<th>Command identifier</th>\n<th>value</th>\n<th>address_pu08</th>\n<th>identifier_u08</th>\n<th>Comment</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_CMD_STARTUP</td>\n<td>0x01</td>\n<td>unused</td>\n<td>unused</td>\n<td>startup the library</td>\n</tr>\n<tr>\n<td>EEL_CMD_SHUTDOWN</td>\n<td>0x07</td>\n<td>unused</td>\n<td>unused</td>\n<td>shutdown the library</td>\n</tr>\n<tr>\n<td>EEL_CMD_VERIFY</td>\n<td>0x05</td>\n<td>unused</td>\n<td>unused</td>\n<td>verify the current active block</td>\n</tr>\n<tr>\n<td>EEL_CMD_REFRESH</td>\n<td>0x04</td>\n<td>unused</td>\n<td>unused</td>\n<td>copy latest instances to new block</td>\n</tr>\n<tr>\n<td>EEL_CMD_Format</td>\n<td>0x06</td>\n<td>unused</td>\n<td>unused</td>\n<td>format the EEL pool</td>\n</tr>\n<tr>\n<td>EEL_CMD_READ</td>\n<td>0x03</td>\n<td>used</td>\n<td>used</td>\n<td>read variable content</td>\n</tr>\n<tr>\n<td>EEL_CMD_WRITE</td>\n<td>0x02</td>\n<td>used</td>\n<td>used</td>\n<td>update variable content</td>\n</tr>\n</tbody>\n</table>\n\n**Note:**\nAlthough it depends on the command which members of the request structure are necessary for the execution, all members of the request variable must be initialized once (for instance directly after variable declaration). Thereby, unused members in the request variable can be to set arbitrary values.\nIn general, all EEL commands can be handled in the same way as illustrated in Figure 4-2 (a corresponding code example can be found in Section 4.3.8):\n\n1. The requester fills up the private request variable my_request (command definition)\n2. The requester tries to initiate the command execution by EEL_Execute(&my_request)\n3. In case of a command rejection, the requester has to call the EEL_Handler first to proceed the processing of the already pending request and can retry by continuing with step 2.\n4. The requester has to call EEL_Handler to proceed the EEL command execution as long the request is being processed (i.e. my_request.status_enu == EEL_BUSY).\n5. After finishing the command (i.e. my_request.status_enu != EEL_BUSY) the requester has to analyze the status to detect potential errors.\n\nNot all commands can/should be executed from every library state. For details, please have a look at the basic workflow shown in Figure 3-3, Section 3.2.\nThe detailed command descriptions given in the subsequent sections include a classification of the corresponding returned statuses according to their severity:\n\n- **normal**: normal operation status by the application has to handle at runtime,\n- **light**: wrong handling that can be corrected by the application at runtime,\n- **heavy**: wrong handling that can be corrected by redesign of the application,\n- **fatal**: cannot be corrected without loss of data.\n4.3.1 Startup\n\nOne main task of the startup command is to check the consistency of the EEL-pool. Especially the structure and consistency of the active block is checked (see also Section 2.3). Thereby, scenarios of reset-caused incomplete command executions are detected. Pool data structures of incomplete write and refresh commands are ignored and the previous data set is treated as valid.\n\nFurthermore, during startup a reference table with indices of the effective instances of all EEL variables is built up in the RAM for fast access to the variable content.\n\nBesides these two main tasks, the startup command also checks important parts of the active EEL block for full data retention (c.f. internal-verify command of Tiny FDL). If it is detected that the full data retention is not given, this is indicated by the error code EEL_ERR_VERIFY. In this case, the user should consider invoking a refresh command.\n\nA successfully executed startup command enables read and write access to the EEL variables.\n\nTable 4-3: Request variable usage for startup command\n\n<table>\n<thead>\n<tr>\n<th>command_enu</th>\n<th>address_pu08</th>\n<th>identifier_u08</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_CMD_STARTUP</td>\n<td>unused</td>\n<td>unused</td>\n</tr>\n</tbody>\n</table>\n\nTable 4-4: Statuses returned by the startup command\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n</table>\n| EEL_ERR_INITIALIZATION | heavy | meaning: EEL or FDL not initialized or not opened \n| | | reason: wrong handling on user side \n| | | remedy: initialize and open EEL before using it |\n| EEL_ERR_INTERNAL | heavy | meaning: error occurred but cannot be categorized \n| | | reason: FDL might have been reinitialized with a different descriptor or an unexpected internal error occurred \n| | | remedy: check/adjust the configured FDL descriptor and re-initialize all libraries. |\n| EEL_ERR_PARAMETER | light | meaning: invalid command code \n| | | reason: unknown command code used in request \n| | | remedy: use command identifiers of eel_command_t |\n| EEL_ERR_VERIFY | light | meaning: found data without full data retention in the block header or the last written variable instance \n| | | reason: long period of time since last refresh, interrupted write sequence (e.g. by reset) \n| | | remedy: execute a refresh command |\n| EEL_ERR_POOL_INCONSISTENT | heavy | meaning: pool structure not usable \n| | | reason: EEL-pool is inconsistent and cannot be recovered \n| | | remedy: format the EEL pool |\n| EEL_ERR_POOL_EXHAUSTED | fatal | meaning: EEL pool size is smaller than 2 blocks, write and refresh is not possible, reading existing variables is still possible \n| | | reason: too many blocks excluded \n<p>| | | remedy: try to perform a format or just read existing data |</p>\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_ERR_REJECTED</td>\n<td>normal</td>\n<td>meaning: EEL cannot accept the request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: EEL is busy with another request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler and retry</td>\n</tr>\n<tr>\n<td>EEL_BUSY</td>\n<td>normal</td>\n<td>meaning: request is being processed</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: request checked and accepted</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler until status changes</td>\n</tr>\n<tr>\n<td>EEL_OK</td>\n<td>normal</td>\n<td>meaning: request was finished regularly</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: no problems during command execution</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: nothing</td>\n</tr>\n</tbody>\n</table>\n\n**Note:**\nA code example how to use the startup command can be found in Section 4.3.8.1.\n4.3.2 Verify\n\nThe verify command performs the verification of the active block in the EEL pool, i.e. checks if all bytes in the active block provide full data retention. The user can execute the verify command after the library has been started up in order to ensure that no weak data were produced by a reset during writing. The developer can also execute the verify command before a shutdown in order to ensure that the EEL data will remain stable for the full data retention time after ending the EEL operation.\n\nTable 4-5: Request variable usage for verify command\n\n<table>\n<thead>\n<tr>\n<th>command_enu</th>\n<th>address_pu08</th>\n<th>identifier_u08</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_CMD_VERIFY</td>\n<td>unused</td>\n<td>unused</td>\n</tr>\n</tbody>\n</table>\n\nTable 4-6: Statuses returned by the verify command\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_ERR_INITIALIZATION</td>\n<td>heavy</td>\n<td>meaning EEL or FDL not initialized or not opened</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason wrong handling on user side</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy initialize and open EEL before using it</td>\n</tr>\n<tr>\n<td>EEL_ERR_INTERNAL</td>\n<td>heavy</td>\n<td>meaning error occurred but cannot be categorized</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason FDL might have been reinitialized with a different descriptor or an unexpected internal error occurred</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy check/adjust the configured FDL descriptor and re-initialize all libraries.</td>\n</tr>\n<tr>\n<td>EEL_ERR_PARAMETER</td>\n<td>light</td>\n<td>meaning invalid command code</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason unknown command code used in request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy use command identifiers of eel_command_t</td>\n</tr>\n<tr>\n<td>EEL_ERR_ACCESS_LOCKED</td>\n<td>light</td>\n<td>meaning no access to EEL pool</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason startup not executed or not successful</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy execute startup command</td>\n</tr>\n<tr>\n<td>EEL_ERR_VERIFY</td>\n<td>heavy</td>\n<td>meaning found data without full data retention in the active block</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason long period of time since last refresh, interrupted write sequence (e.g. by reset)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy execute refresh soon</td>\n</tr>\n<tr>\n<td>EEL_ERR_REJECTED</td>\n<td>normal</td>\n<td>meaning EEL cannot accept the request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason EEL is busy with another request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy call EEL_Handler and retry</td>\n</tr>\n<tr>\n<td>EEL_BUSY</td>\n<td>normal</td>\n<td>meaning request is being processed</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason request checked and accepted</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy call EEL_Handler until status changes</td>\n</tr>\n<tr>\n<td>EEL_OK</td>\n<td>normal</td>\n<td>meaning request was finished regularly</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason no problems during command execution</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy nothing</td>\n</tr>\n</tbody>\n</table>\n\nNote:\nA code example how to use the verify command can be found in Section 4.3.8.4.\n4.3.3 Shutdown\n\nThe shutdown command locks the logical access to the EEL data. To ensure full data retention time for all data in the active block, it is recommended to execute the verify command and—in case of an error—to perform a refresh before shutting down the library.\n\nNote:\nThe shutdown command is the only command which has single processing state and hence finishes with EEL_Execute directly (i.e. without additional EEL_Handler call, c.f. Figure 3-3 in Section 3.2). However, the developer is advised to follow the common command flow proposed in Figure 4-2 also for the shutdown command.\n\nTable 4-7: Request variable usage for startup command\n\n<table>\n<thead>\n<tr>\n<th>command_enu</th>\n<th>address_pu08</th>\n<th>identifier_u08</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_CMD_SHUTDOWN</td>\n<td>unused</td>\n<td>unused</td>\n</tr>\n</tbody>\n</table>\n\nTable 4-8: Statuses returned by the shutdown command\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_ERR_INITIALIZATION</td>\n<td>heavy</td>\n<td>meaning: EEL or FDL not initialized or not opened</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: wrong handling on user side</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: initialize and open EEL before using it</td>\n</tr>\n<tr>\n<td>EEL_ERR_PARAMETER</td>\n<td>light</td>\n<td>meaning: invalid command code</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: unknown command code used in request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: use command identifiers of eel_command_t</td>\n</tr>\n<tr>\n<td>EEL_ERR_ACCESS_LOCKED</td>\n<td>light</td>\n<td>meaning: no access to EEL pool</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: startup not executed or not successful</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: execute startup command</td>\n</tr>\n<tr>\n<td>EEL_ERR_REJECTED</td>\n<td>normal</td>\n<td>meaning: EEL cannot accept the request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: EEL is busy with another request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler and retry</td>\n</tr>\n<tr>\n<td>EEL_BUSY</td>\n<td>normal</td>\n<td>meaning: request is being processed</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: request checked and accepted</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler until status changes</td>\n</tr>\n<tr>\n<td>EEL_OK</td>\n<td>normal</td>\n<td>meaning: request was finished regularly</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: no problems during command execution</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: nothing</td>\n</tr>\n</tbody>\n</table>\n\nNote:\nA code example how to use the startup command can be found in Section 4.3.8.4.\n4.3.4 Format\n\nThe format command destroys all EEL variable content and creates an empty EEL pool with one active block. All remaining blocks are erased, independently of their block status. This means that also excluded blocks are tried to be erased, offering the developer a way to try to reanimate these blocks. However, in case of repeated erase problems, the format command excludes blocks automatically.\n\nTypically, the format command is executed before the library is started up. However, it is also possible to execute the format command when the library has been started up already. In any case, the library needs to be started up again after a successful format.\n\nIn contrast to all other Tiny EEL commands, the format command is not robust against resets. In case a reset occurs during a format, there is a chance that the EEL pool is coincidentally valid and will be accepted during the next startup. Please ensure to always finish a once started format command.\n\nPlease note that this ostensible limitation is not severe in the typical use case as a format command destroys all EEL variable content and is therefore usually executed once at the beginning of a product lifetime.\n\nNote:\nWhen executing a format command, all EEL variable data will be lost immediately.\n\nCaution 1:\nIt is imperative to finish a once started format command. The format command is not robust against resets. Unfinished format commands may not be detected and can lead to unpredictable behavior (i.e. data sets) during the next startup.\n\nCaution 2:\nWhen changing the FDL descriptor, an EEL format command must be executed successfully before the EEL can be started up and used again.\n\n<table>\n<thead>\n<tr>\n<th>command_enu</th>\n<th>address_pu08</th>\n<th>identifier_u08</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_CMD_FORMAT</td>\n<td>unused</td>\n<td>unused</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_ERR_INITIALIZATION</td>\n<td>heavy</td>\n<td>meaning: EEL or FDL not initialized or not opened</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: wrong handling on user side</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: initialize and open EEL before using it</td>\n</tr>\n<tr>\n<td>EEL_ERR_INTERNAL</td>\n<td>heavy</td>\n<td>meaning: error occurred but cannot be categorized</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: FDL might have been reinitialized with a different descriptor or an unexpected internal error occurred</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: check/adjust the configured FDL descriptor and re-initialize all libraries.</td>\n</tr>\n<tr>\n<td>EEL_ERR_PARAMETER</td>\n<td>light</td>\n<td>meaning: invalid command code</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: unknown command code used in request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: use command identifiers of eel_command_t</td>\n</tr>\n</tbody>\n</table>\n### Status and Handling\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_ERR_POOL_EXHAUSTED</td>\n<td>fatal</td>\n<td>meaning: EEL pool size is smaller than 2 blocks, write and refresh is not possible, reading existing variables is still possible.</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: too many blocks excluded</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: try to perform a format or just read existing data</td>\n</tr>\n<tr>\n<td>EEL_ERR_REJECTED</td>\n<td>normal</td>\n<td>meaning: EEL cannot accept the request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: EEL is busy with another request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler and retry</td>\n</tr>\n<tr>\n<td>EEL_BUSY</td>\n<td>normal</td>\n<td>meaning: request is being processed</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: request checked and accepted</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler until status changes</td>\n</tr>\n<tr>\n<td>EEL_OK</td>\n<td>normal</td>\n<td>meaning: request was finished regularly</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: no problems during command execution</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: nothing</td>\n</tr>\n</tbody>\n</table>\n\n**Note:**\nA code example how to use the format command can be found in Section 4.3.8.2\n4.3.5 Refresh\n\nThe refresh command copies the latest instance of each variable from the active block (source block) to the next block (destination block) in the EEL pool ring counting clockwise (see Section 2.3.1). Thereby, the destination block becomes the new active block.\n\nBy means of the refresh command, new free space is created which can be used to write (i.e. update) variable contents. Another reason for executing a refresh could be to ensure full data retention of all variables for instance before powering down the device.\n\nThe refresh sequence is designed in a way that a valid data set is available at any time. Therefore, the refresh command is robust against reset scenarios. The proper variable set will be reconstructed during the next startup.\n\n**Note:**\nBefore a refresh command can be executed, the library needs to be started up successfully.\n\n### Table 4-11: Request variable usage for refresh command\n\n<table>\n<thead>\n<tr>\n<th><code>command_enu</code></th>\n<th><code>address_pu08</code></th>\n<th><code>identifier_u08</code></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_CMD_REFRESH</td>\n<td>unused</td>\n<td>unused</td>\n</tr>\n</tbody>\n</table>\n\n### Table 4-12: Statuses returned by the refresh command\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n</table>\n| EEL_ERR_INITIALIZATION | heavy | meaning: EEL or FDL not initialized or not opened \n| | | reason: wrong handling on user side \n| | | remedy: initialize and open EEL before using it |\n| EEL_ERR_INTERNAL | heavy | meaning: error occurred but cannot be categorized \n| | | reason: FDL might have been reinitialized with a different descriptor or an unexpected internal error occurred \n| | | remedy: check/adjust the configured FDL descriptor and re-initialize all libraries. |\n| EEL_ERR_PARAMETER | light | meaning: invalid command code \n| | | reason: unknown command code used in request \n| | | remedy: use command identifiers of eel_command_t |\n| EEL_ERR_ACCESS_LOCKED | light | meaning: no access to EEL pool \n| | | reason: startup not executed or not successful \n| | | remedy: execute startup command |\n| EEL_ERR_POOL_EXHAUSTED | fatal | meaning: EEL pool size is smaller than 2 blocks, write and refresh is not possible, reading existing variables is still possible \n| | | reason: too many blocks excluded \n| | | remedy: try to perform a format or just read existing data |\n| EEL_ERR_REJECTED | normal | meaning: EEL cannot accept the request \n| | | reason: EEL is busy with another request \n| | | remedy: call EEL_Handler and retry |\n### Status meaning and handling\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_BUSY</td>\n<td>normal</td>\n<td>meaning request is being processed</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason request checked and accepted</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy call EEL_Handler until status changes</td>\n</tr>\n<tr>\n<td>EEL_OK</td>\n<td>normal</td>\n<td>meaning request was finished regularly</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason no problems during command execution</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy nothing</td>\n</tr>\n</tbody>\n</table>\n\n**Note:**\nA code example how to use the refresh command can be found in Section 4.3.8.3.\n4.3.6 Write\n\nThe write command writes a new value to an EEL variable. The variable to be updated is specified via the identifier element of the request structure. The data to be written is copied from a buffer pointed to by the address element.\n\nIn case of insufficient free space in the active block, the write command returns EEL_ERR_POOL_FULL. In this case the developer needs to execute a refresh and then try to write the variable again.\n\nIn time critical scenarios it is also possible to check the remaining free space in the active block beforehand by means of the EEL_GetSpace function (see Section 4.2.7). This enables to detect when free space is getting scarce and issue a refresh already early when there is enough processing time. When evaluating the free space returned by EEL_GetSpace, please recall that a variable instance always requires two administrative bytes of data besides the actual variable contend.\n\nThe write sequence is designed in a way that a valid data set is available at any time. Therefore, the write command is robust against reset scenarios. The proper variable content will be reconstructed during the next startup.\n\n**Note 1:**\nPlease ensure that the size of the data buffer used for writing the variable is at least as large as the size of the variable to be written and that all relevant buffer elements are initialized.\n\n**Note 2:**\nBefore a write command can be executed, the library needs to be started up successfully.\n\nTable 4-13: Request variable usage for write command\n\n<table>\n<thead>\n<tr>\n<th>command_enu</th>\n<th>address_pu08</th>\n<th>identifier_u08</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_CMD_WRITE</td>\n<td>pointer to data buffer</td>\n<td>identifier of variable to be written</td>\n</tr>\n</tbody>\n</table>\n\nTable 4-14: Statuses returned by the write command\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_ERR_INITIALIZATION</td>\n<td>heavy</td>\n<td>meaning: EEL or FDL not initialized or not opened</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: wrong handling on user side</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: initialize and open EEL before using it</td>\n</tr>\n<tr>\n<td>EEL_ERR_INTERNAL</td>\n<td>heavy</td>\n<td>meaning: error occurred but cannot be categorized</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: FDL might have been reinitialized with a different descriptor or an unexpected internal error occurred</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: check/adjust the configured FDL descriptor and re-initialize all libraries.</td>\n</tr>\n<tr>\n<td>EEL_ERR_PARAMETER</td>\n<td>light</td>\n<td>meaning: invalid command code</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: unknown command code used in request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: use command identifiers of eel_command_t</td>\n</tr>\n<tr>\n<td>EEL_ERR_ACCESS_LOCKED</td>\n<td>light</td>\n<td>meaning: no access to EEL pool</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: startup not executed or not successful</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: execute startup command</td>\n</tr>\n<tr>\n<td>EEL_ERR_POOL_EXHAUSTED</td>\n<td>fatal</td>\n<td>meaning: EEL pool size is smaller than 2 blocks, write and refresh is not possible, reading existing variables is still possible</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: too many blocks excluded</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: try to perform a format or just read existing data</td>\n</tr>\n</tbody>\n</table>\n### Status and Handling\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_ERR_POOL_FULL</td>\n<td>normal</td>\n<td>meaning: not enough space in active block to write the variable instance</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason:</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• space was consumed by previous write commands</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• flash error occurred during writing data</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• the active block contains an invalid reference (space consumed by previous startup command in case of invalid reference)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>• the active block has weak data (previous startup command returned EEL_ERR_VERIFY error)</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: execute a refresh and write again</td>\n</tr>\n<tr>\n<td>EEL_ERR_REJECTED</td>\n<td>normal</td>\n<td>meaning: EEL cannot accept the request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: EEL is busy with another request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler and retry</td>\n</tr>\n<tr>\n<td>EEL_BUSY</td>\n<td>normal</td>\n<td>meaning: request is being processed</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: request checked and accepted</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler until status changes</td>\n</tr>\n<tr>\n<td>EEL_OK</td>\n<td>normal</td>\n<td>meaning: request was finished regularly</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: no problems during command execution</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: nothing</td>\n</tr>\n</tbody>\n</table>\n\n**Note:**\nA code example how to use the refresh command can be found in Section 4.3.8.3.\n4.3.7 Read\n\nThe read command reads the current value of an EEL variable. The variable to be read is specified via the identifier element of the request structure. The data is copied to a buffer pointed to by the address element.\n\nNote 1:\nPlease ensure that the size of the data buffer used for reading the variable is at least as large as the size of the variable.\n\nNote 2:\nBefore a read command can be executed, the library needs to be started up successfully.\n\nTable 4-15: Request variable usage for read command\n\n<table>\n<thead>\n<tr>\n<th>command_enu</th>\n<th>address_pu08</th>\n<th>identifier_u08</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_CMD_READ</td>\n<td>pointer to data buffer</td>\n<td>identifier of variable to be read</td>\n</tr>\n</tbody>\n</table>\n\nTable 4-16: Statuses returned by the read command\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_ERR_INITIALIZATION</td>\n<td>heavy</td>\n<td>meaning: EEL or FDL not initialized or not opened</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: wrong handling on user side</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: initialize and open EEL before using it</td>\n</tr>\n<tr>\n<td>EEL_ERR_INTERNAL</td>\n<td>heavy</td>\n<td>meaning: error occurred but cannot be categorized</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: FDL might have been reinitialized with a different descriptor or an unexpected internal error occurred</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: check/adjust the configured FDL descriptor and re-initialize all libraries.</td>\n</tr>\n<tr>\n<td>EEL_ERR_PARAMETER</td>\n<td>light</td>\n<td>meaning: invalid command code</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: unknown command code used in request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: use command identifiers of eel_command_t</td>\n</tr>\n<tr>\n<td>EEL_ERR_ACCESS_LOCKED</td>\n<td>light</td>\n<td>meaning: no access to EEL pool</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: startup not executed or not successful</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: execute startup command</td>\n</tr>\n<tr>\n<td>EEL_ERR_NO_INSTANCE</td>\n<td>light</td>\n<td>meaning: no instance of the variable with the specified identifier found</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: no initial value written</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: write an initial value of the variable via the write command</td>\n</tr>\n<tr>\n<td>EEL_ERR_REJECTED</td>\n<td>normal</td>\n<td>meaning: EEL cannot accept the request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: EEL is busy with another request</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler and retry</td>\n</tr>\n<tr>\n<td>EEL_BUSY</td>\n<td>normal</td>\n<td>meaning: request is being processed</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>reason: request checked and accepted</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>remedy: call EEL_Handler until status changes</td>\n</tr>\n</tbody>\n</table>\n### Status and Class:\n\n<table>\n<thead>\n<tr>\n<th>Status</th>\n<th>Class</th>\n<th>Status meaning and handling</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_OK</td>\n<td>normal</td>\n<td>request was finished regularly</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>no problems during command execution</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>nothing</td>\n</tr>\n</tbody>\n</table>\n\n**Note:**\nA code example how to use the `refresh` command can be found in Section 4.3.8.3.\n4.3.8 Code examples\n\nIn the following, some code examples are given how to initiate and execute EEL commands.\n\n4.3.8.1 Library Startup\n\n```c\neel_status_t my_eel_status;\neel_request_t my_eel_request_str;\n...\n\n/* It is assumed at this point, that the FDL has been initialized and opened correctly. */\nmy_eel_status = EEL_Init();\nif (my_eel_status != EEL_OK)\n{\n MyErrorHandler();\n}\nEEL_Open();\n\n/* Ensure initialized request structure ---------------------------------------------*/\nmy_eel_request_str.command_enu = EEL_CMD_UNDEFINED;\nmy_eel_request_str.identifier_u08 = 0;\nmy_eel_request_str.address_pu08 = NULL;\nmy_eel_request_str.status_enu = EEL_ERR_PARAMETER;\n\n/* Initiate STARTUP command --------------------------------------------------------*/\nmy_eel_request_str.command_enu = EEL_CMD_STARTUP;\n/* command cannot be rejected here as the library has just been opened */\nEEL_Execute(&my_eel_request_str);\nwhile (my_eel_request_str.status_enu == EEL_BUSY)\n{\n EEL_Handler();\n}\nif (my_eel_request_str.status_enu != EEL_OK)\n{\n MyErrorHandler();\n}\n\n/* Library is started up now and should accept accesses to the EEL variables */\n\n/* Initiate READ command ----------------------------------------------------------*/\nmy_eel_request_str.command_enu = EEL_CMD_READ;\nmy_eel_request_str.address_pu08 = (__near eel_u08*)&A[0];\nmy_eel_request_str.identifier_u08 = 1;\n\ndo\n{\n EEL_Handler();\n EEL_Execute(&my_eel_request_str);\n} while (my_eel_request_str.status_enu == EEL_ERR_REJECTED);\n\nwhile (my_eel_request_str.status_enu == EEL_BUSY)\n{\n EEL_Handler();\n}\nif (my_eel_request_str.status_enu != EEL_OK)\n{\n MyErrorHandler();\n}\n```\n4.3.8.2 EEL Pool Format\n\n```c\neel_status_t my_eel_status;\neel_request_t my_eel_request_str;\n\n/* Ensure initialized request structure ----------------------------------- */\nmy_eel_request_str.command_enu = EEL_CMD_UNDEFINED;\nmy_eel_request_str.identifier_u08 = 0;\nmy_eel_request_str.address_pu08 = NULL;\nmy_eel_request_str.status_enu = EEL_ERR_PARAMETER;\n...\n\n/* It is assumed at this point, that the FDL has been initialized and opened\n correctly. */\nmy_eel_status = EEL_Init();\nif (my_eel_status != EEL_OK)\n{\n MyErrorHandler();\n}\nEEL_Open();\n\n/* Initiate FORMAT command ----------------------------------------------- */\nmy_eel_request_str.command_enu = EEL_CMD_FORMAT;\n\n/* command cannot be rejected here as the library has just been opened */\nEEL_Execute(&my_eel_request_str);\nwhile (my_eel_request_str.status_enu == EEL_BUSY)\n{\n EEL_Handler();\n}\nif (my_eel_request_str.status_enu != EEL_OK)\n{\n MyErrorHandler();\n}\n\n/* EEL pool is formatted now, all previous variable content is lost */\n```\n4.3.8.3 Variable Access\n\n```c\neel_status_t my_eel_status;\neel_request_t my_eel_request_str;\neel_request_t my_refr_eel_request_str;\n\n/* Ensure initialized request structure ----------------------------------- */\nmy_eel_request_str.command_enu = EEL_CMD_UNDEFINED;\nmy_eel_request_str.identifier_u08 = 0;\nmy_eel_request_str.address_pu08 = NULL;\nmy_eel_request_str.status_enu = EEL_ERR_PARAMETER;\n\nmy_refr_eel_request_str.command_enu = EEL_CMD_REFRESH;\nmy_refr_eel_request_str.identifier_u08 = 0;\nmy_refr_eel_request_str.address_pu08 = NULL;\nmy_refr_eel_request_str.status_enu = EEL_ERR_PARAMETER;\n...\n\n/* It is assumed at this point, that the EEL has been initialized, opened and\n started up correctly. */\n\n/* Initiate READ command ---------------------------------------------------- */\nmy_eel_request_str.command_enu = EEL_CMD_READ;\nmy_eel_request_str.address_pu08 = (__near eel_u08*)&A[0];\nmy_eel_request_str.identifier_u08 = 2;\n\ndo\n {\n EEL_Handler();\n EEL_Execute(&my_eel_request_str);\n }\nwhile (my_eel_request_str.status_enu == EEL_ERR_REJECTED);\n\nwhile (my_eel_request_str.status_enu == EEL_BUSY)\n {\n EEL_Handler();\n }\n\nif (my_eel_request_str.status_enu != EEL_OK)\n {\n MyErrorHandler();\n }\n\n/* Initiate WRITE command -------------------------------------------------- */\nmy_eel_request_str.command_enu = EEL_CMD_WRITE;\nmy_eel_request_str.address_pu08 = (__near eel_u08*)&B[0];\nmy_eel_request_str.identifier_u08 = 1;\n\ndo\n {\n do\n {\n EEL_Handler();\n EEL_Execute(&my_eel_request_str);\n }\n while (my_eel_request_str.status_enu == EEL_ERR_REJECTED);\n\n while (my_eel_request_str.status_enu == EEL_BUSY)\n {\n EEL_Handler();\n }\n\n if (my_eel_request_str.status_enu == EEL_ERR_POOL_FULL)\n {\n```\n/* in case of a full pool, a refresh needs to be executed\n in order to free space */\n\n/* please note that a different request variable is used for the\n refresh so that the result of the write command can be checked in the\n outer loop */\ndo{\n EEL_Handler();\n EEL_Execute(&my_refr_eel_request_str);\n} while (my_refr_eel_request_str.status_enu == EEL_ERR_REJECTED);\n\nwhile (my_refr_eel_request_str.status_enu == EEL_BUSY) {\n EEL_Handler();\n}\n\nif (my_refr_eel_request_str.status_enu != EEL_OK) {\n MyErrorHandler();\n}\nelse if (my_eel_request_str.status_enu != EEL_OK) {\n MyErrorHandler();\n}\n} while (my_eel_request_str.status_enu == EEL_ERR_POOL_FULL);\n\n4.3.8.4 Library Shutdown\n\neel_status_t my_eel_status;\neel_request_t my_eel_request_str;\n\n/* Ensure initialized request structure ------------------------------ */\nmy_eel_request_str.command_enu = EEL_CMD_UNDEFINED;\nmy_eel_request_str.identifier_u08 = 0;\nmy_eel_request_str.address_pu08 = NULL;\nmy_eel_request_str.status_enu = EEL_ERR_PARAMETER;\n...\n\n/* It is assumed at this point, that the library has been initialized, opened\n and started up correctly. */\n\n/* Initiate VERIFY command ----------------------------------------- */\nmy_eel_request_str.command_enu = EEL_CMD_VERIFY;\ndo{\n EEL_Handler();\n EEL_Execute(&my_eel_request_str);\n} while (my_eel_request_str.status_enu == EEL_ERR_REJECTED);\n\nwhile (my_eel_request_str.status_enu == EEL_BUSY) {\n EEL_Handler();\n}\n/* Check if a refresh is required for full data retention before device is powered down. */\nmy_do_refresh = false;\nif (my_eel_request_str.status_enu == EEL_ERR_VERIFY)\n{\n my_do_refresh = true;\n}\nelse if (my_eel_request_str.status_enu != EEL_OK)\n{\n MyErrorHandler();\n}\nif (my_do_refresh)\n{\n /* Initiate REFRESH command --------------------------------------- */\n my_eel_request_str.command_enu = EEL_CMD_REFRESH;\n do\n {\n EEL_Handler();\n EEL_Execute(&my_eel_request_str);\n } while (my_eel_request_str.status_enu == EEL_ERR_REJECTED);\n\n while (my_eel_request_str.status_enu == EEL_BUSY)\n {\n EEL_Handler();\n }\n\n if (my_eel_request_str.status_enu != EEL_OK)\n {\n MyErrorHandler();\n }\n}\n\n/* Initiate SHUTDOWN command ------------------------------------------ */\nmy_eel_request_str.command_enu = EEL_CMD_SHUTDOWN;\n\n do\n {\n EEL_Handler();\n EEL_Execute(&my_eel_request_str);\n } while (my_eel_request_str.status_enu == EEL_ERR_REJECTED);\n\n while (my_eel_request_str.status_enu == EEL_BUSY)\n {\n EEL_Handler();\n }\n\n if (my_eel_request_str.status_enu != EEL_OK)\n {\n MyErrorHandler();\n }\n\n EEL_Close();\nChapter 5 Library Setup and Usage\n\nThis chapter contains important information about how to put the Tiny EEL into operation and how to integrate it into your application. Please read this chapter carefully—and also especially Chapter 6 “Cautions”—in order to avoid problems and misbehavior of the library. Before integrating the library into your project however, please make sure that you have read and understood how the Tiny EEL works and which basic concepts are used (see Chapter 2 and Chapter 3).\n\n5.1 Obtaining the Library\n\nThe Tiny EEL is provided by means of an installer via the Renesas homepage at http://www.renesas.eu/updates?oc=EEPROM_EMULATION_RL78. Please follow the instructions of the installer carefully and read the user manual which is also available there. For operation, the Tiny EEL requires the corresponding FDL (RL78 FDL Type T02, Tiny FDL). Please ensure to always work on the latest version of both libraries.\n\n5.2 File Structure\n\nThe Tiny EEL is delivered as precompiled library for the CA78K0R, IAR V1.xx, IAR V2.xx, GNU and CC-RL compilers. The library and its header files are stored in the lib subdirectory inside the installation folder. The Sample directory contains sample setups which are no integral part of the library itself and should be modified according to the project needs. The structure of the files in each tool chain is shown in the table.\n\nTable 5-1: Common files of the Tiny EEL\n\n<table>\n<thead>\n<tr>\n<th>File</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><installation folder></td>\n<td>contains release-specific information about the installed library</td>\n</tr>\n<tr>\n<td>Release.txt</td>\n<td>library support information</td>\n</tr>\n</tbody>\n</table>\n\nTable 5-2: File structure of the Tiny EEL for CA78K0R tool chain\n\n<table>\n<thead>\n<tr>\n<th><installation folder>/CA78K0R_xxx/EEL/lib</th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>eel.h</td>\n<td>EEL header file, EEL interface definition</td>\n</tr>\n<tr>\n<td>eel_types.h</td>\n<td>EEL header file, EEL types definition</td>\n</tr>\n<tr>\n<td>eel.inc</td>\n<td>EEL assembler include file with interface definition</td>\n</tr>\n<tr>\n<td>eel_types.inc</td>\n<td>EEL assembler include file with EEL types definition</td>\n</tr>\n<tr>\n<td>eel.lib</td>\n<td>precompiled library file</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th><installation folder>/CA78K0R_xxx/EEL/Sample/C</th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>eel_descriptor.c</td>\n<td>user defined EEL-variable descriptor</td>\n</tr>\n<tr>\n<td>eel_descriptor.h</td>\n<td>EEL configuration part</td>\n</tr>\n<tr>\n<td>eel_user_types.h</td>\n<td>sample user types for EEL variables</td>\n</tr>\n<tr>\n<td>eel_sample_linker_file.dr</td>\n<td>linker sample file</td>\n</tr>\n</tbody>\n</table>\n\n<table>\n<thead>\n<tr>\n<th><installation folder>/CA78K0R_xxx/EEL/Sample/asm</th>\n<th></th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>eel_descriptor.asm</td>\n<td>user defined EEL-variable descriptor and sample user types</td>\n</tr>\n<tr>\n<td>eel_descriptor.inc</td>\n<td>EEL configuration part</td>\n</tr>\n<tr>\n<td>eel_sample_linker_file.dr</td>\n<td>linker sample file</td>\n</tr>\n</tbody>\n</table>\n### Table 5-3: File structure of the Tiny EEL for IAR V1.xx tool chain\n\n<table>\n<thead>\n<tr>\n<th>File Structure</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code><installation folder>/IAR_1xx/EEL/lib</code></td>\n<td></td>\n</tr>\n<tr>\n<td>eel.h</td>\n<td>EEL header file, EEL interface definition</td>\n</tr>\n<tr>\n<td>eel_types.h</td>\n<td>EEL header file, EEL types definition</td>\n</tr>\n<tr>\n<td>eel.r87</td>\n<td>precompiled library file</td>\n</tr>\n<tr>\n<td><code><installation folder>/IAR_1xx/EEL/Sample/C</code></td>\n<td></td>\n</tr>\n<tr>\n<td>eel_descriptor.c</td>\n<td>user defined EEL-variable descriptor</td>\n</tr>\n<tr>\n<td>eel_descriptor.h</td>\n<td>EEL configuration part</td>\n</tr>\n<tr>\n<td>eel_user_types.h</td>\n<td>sample user types for EEL variables</td>\n</tr>\n<tr>\n<td>eel_sample_linker_file.xcl</td>\n<td>linker sample file</td>\n</tr>\n</tbody>\n</table>\n\n### Table 5-4: File structure of the Tiny EEL for IAR V2.xx tool chain\n\n<table>\n<thead>\n<tr>\n<th>File Structure</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code><installation folder>/IAR_2xx/EEL/lib</code></td>\n<td></td>\n</tr>\n<tr>\n<td>eel.h</td>\n<td>EEL header file, EEL interface definition</td>\n</tr>\n<tr>\n<td>eel_types.h</td>\n<td>EEL header file, EEL types definition</td>\n</tr>\n<tr>\n<td>eel.a</td>\n<td>precompiled library file</td>\n</tr>\n<tr>\n<td><code><installation folder>/IAR_2xx/Sample/C</code></td>\n<td></td>\n</tr>\n<tr>\n<td>eel_descriptor.c</td>\n<td>user defined EEL-variable descriptor</td>\n</tr>\n<tr>\n<td>eel_descriptor.h</td>\n<td>EEL configuration part</td>\n</tr>\n<tr>\n<td>eel_user_types.h</td>\n<td>sample user types for EEL variables</td>\n</tr>\n<tr>\n<td>eel_sample_linker_file.icf</td>\n<td>linker sample file</td>\n</tr>\n</tbody>\n</table>\n\n### Table 5-5: File structure of the Tiny EEL for GNU tool chain\n\n<table>\n<thead>\n<tr>\n<th>File Structure</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td><code><installation folder>/GNU_xxxx/EEL/lib</code></td>\n<td></td>\n</tr>\n<tr>\n<td>eel.h</td>\n<td>EEL header file, EEL interface definition</td>\n</tr>\n<tr>\n<td>eel_types.h</td>\n<td>EEL header file, EEL types definition</td>\n</tr>\n<tr>\n<td>eel.a</td>\n<td>precompiled library file</td>\n</tr>\n<tr>\n<td><code><installation folder>/GNU_xxxx/Sample/C</code></td>\n<td></td>\n</tr>\n<tr>\n<td>eel_descriptor.c</td>\n<td>user defined EEL-variable descriptor</td>\n</tr>\n<tr>\n<td>eel_descriptor.h</td>\n<td>EEL configuration part</td>\n</tr>\n<tr>\n<td>eel_user_types.h</td>\n<td>sample user types for EEL variables</td>\n</tr>\n<tr>\n<td>eel_sample_linker_file.ld</td>\n<td>linker sample file</td>\n</tr>\n</tbody>\n</table>\n5.3 Library Resources\n\nIn the subsequent sections, the resources utilized by the library are described in detail.\n\n5.3.1 Resource Consumption\n\nThe Tiny EEL is allocated together with the program in the user area, occupying an area equal to the size of the library. Furthermore, the library itself uses the CPU, the stack, internal data and data buffers (for read/write access to the EEL variables).\n\nDetailed information about the required software resources is listed in Table 5-7. All resource consumption numbers are based on the Tiny EEL V1.00. Please note, that the Tiny EEL requires the Tiny FDL (Type T02) for operation. The resource consumption of the Tiny FDL can be found in the associated user manual. It is not possible to use the Tiny EEL with any other FDL than the Tiny FDL (Type T02), i.e. FDL and EEL have always to be used as a bundle (RL78 FDL T01 with RL78 EEL T01, and RL78 FDL T02 with RL78 EEL T02).\n\nTable 5-7: Resource consumption of the Tiny EEL V1.00\n\n<table>\n<thead>\n<tr>\n<th>Resource</th>\n<th>CA78K0R Compiler</th>\n<th>IAR V1.xx Compiler</th>\n<th>IAR V2xx Compiler</th>\n<th>GNU Compiler</th>\n<th>CC-RL Compiler</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>maximum code size (code flash)</td>\n<td>2746 bytes</td>\n<td>2768 bytes</td>\n<td>2721 bytes</td>\n<td>2769 bytes</td>\n<td>2721 bytes</td>\n</tr>\n<tr>\n<td>constants (code flash)</td>\n<td><EEL variable count> + 4 bytes</td>\n<td>< EEL variable count > + 4 bytes</td>\n<td>< EEL variable count > + 4 bytes</td>\n<td>< EEL variable count > + 4 bytes</td>\n<td>< EEL variable count > + 4 bytes</td>\n</tr>\n<tr>\n<td>internal data (RAM, short address area)</td>\n<td>1 byte Note</td>\n<td>1 byte Note</td>\n<td>1 byte Note</td>\n<td>1 byte Note</td>\n<td>1 byte Note</td>\n</tr>\n<tr>\n<td>maximum stack usage (including FDL)</td>\n<td>80 bytes</td>\n<td>80 bytes</td>\n<td>64 bytes</td>\n<td>92 bytes</td>\n<td>64 bytes</td>\n</tr>\n</tbody>\n</table>\n\nNote:\nDepending on the used device, the Tiny EEL may use a fraction of the user RAM as working area. Size and location of this area is strictly device dependent, see Section 5.3.3 for more details.\n5.3.2 Linker Sections\n\nThe following sections are related to the Tiny EEL and need to be defined in the linker file (please see eel_sample_linker_file.dr or eel_sample_linker_file.xcl for an example):\n\n- **FDL_CODE**: Segment containing the code of the Tiny FDL.\n- **FDL_SDAT**: Data segment of the Tiny FDL containing all FDL-internal variables. Needs to be placed in the short address area of the RAM.\n- **FDL_CNST**: Segment for Tiny FDL constants.\n- **EEL_CODE**: Segment containing the code of the Tiny EEL.\n- **EEL_SDAT**: Data segment of the Tiny EEL containing all EEL-internal variables. Needs to be placed in the short address area of the RAM.\n- **EEL_CNST**: Segment containing EEL constants.\n\n**Note 1:**\nThe FDL_CODE and FDL_CNST as well as the EEL_CODE and EEL_CNST segments can be located anywhere inside the code flash, but must be inside the same 64 KB page.\n\n**Note 2:**\nThe FDL_SDAT and EEL_SDAT segments must be located in the short address area of the RAM.\n\n**Note 3:**\nNot all library functions are linked. Unused functions are not included in the linked executable. For the CA78K0R assembler, linking can be reduced to a subset of the library functions by deleting unnecessary functions from the include file.\n\n5.3.3 Prohibited RAM Area\n\nThe Tiny EEL may use a fraction of the user RAM as working area, referred as prohibited RAM area. The size and position of this area is strictly device dependent (many devices do not even have this area) and vary between the different RL78 products. For details, please refer to the document “User's Manual: Hardware” of your RL78 product.\n\nIf a prohibited RAM area is specified for the utilized device, it is not allowed to access this area while the Tiny EEL is active. Whenever EEL functions are called, the data in the prohibited area may be rewritten.\n\n5.3.4 Stack and Data Buffer\n\nThe Tiny EEL has to handle some rather complex tasks in order to manage the EEL variables. As this management is run directly on the CPU, the library utilizes the same stack as specified in the user application. It is the developer’s duty to reserve enough free stack for the operation of both, user application and EEL.\n\nThe data buffer used by the Tiny EEL refers to the RAM area in which data is located that is to be written into the data flash and where data is to be copied to when an EEL variable is read. These buffers need to be allocated and managed by the user.\n\n**Note:**\nIn order to allocate the stack and data buffer to a user-specified address, please utilize the link directives of your framework.\n\n**Caution:**\nIn contrast to the internal EEL data (EEL_SDAT segment), both stack and data buffer may not be allocated in the short address range from 0xFFE20 to 0xFFEFF—and also not in the prohibited RAM area, if it exists in the target device.\n5.3.5 Register Usage\n\nThe CA78K0R, IAR V1.xx, IAR V2.xx and CC-RL releases of the Tiny EEL use the registers of the currently selected register bank. No implicit register bank switch is performed by the library.\n\nFor the GNU release of the Tiny EEL, it is mandatory that register bank 0 is active on function entry. No implicit register bank switch is performed by the library. Return values are placed in register bank 1. For details on GNU calling conventions, please refer to the GNU documentation for RL78 devices.\n\nNote:\nA detailed description of the registers used for parameter passing and return values can be found in Section 0 along with the detailed function descriptions.\n\n5.3.6 Library Timings\n\nIn the following, certain timing characteristics of the Tiny EEL are specified. As the Tiny EEL accesses the Tiny FDL directly, the FDL timings affect also those of the EEL. All timing specifications are based on the following library versions:\n\n- Tiny EEL: V1.00\n- Tiny FDL: V1.01\n\nPlease note that there might be deviations from the specified timings in case you are using other library versions than the ones mentioned.\n\n5.3.6.1 Maximum Function Execution Times\n\nThe maximum function execution times are listed in Table 5-8. These timings can be seen as worst case durations of the specific EEL function calls and therefore can aid the developer for time critical considerations, e.g. when setting up the watchdog timer. Please note however, that the typical and minimum function execution times can be much shorter. Especially the EEL_Handler consumes only a few clock cycles when the EEL driver is in idle state.\n\nPlease note that the Tiny EEL function execution times are independent of the operation mode of the device (full speed or wide voltage). Also, these timings do not contain any frequency-independent part and are therefore specified in terms of numbers of cycles.\n\n<table>\n<thead>\n<tr>\n<th>Function name</th>\n<th>Maximum function execution time [cycles]</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>EEL_Init</td>\n<td>708 + 40 per EEL variable</td>\n</tr>\n<tr>\n<td>EEL_Open</td>\n<td>14</td>\n</tr>\n<tr>\n<td>EEL_Close</td>\n<td>17</td>\n</tr>\n<tr>\n<td>EEL_Execute</td>\n<td>320</td>\n</tr>\n<tr>\n<td>EEL_Handler</td>\n<td>4582</td>\n</tr>\n<tr>\n<td>EEL_GetDriverStatus</td>\n<td>245</td>\n</tr>\n<tr>\n<td>EEL_GetSpace</td>\n<td>47</td>\n</tr>\n<tr>\n<td>EEL_GetVersionString</td>\n<td>14</td>\n</tr>\n</tbody>\n</table>\n5.3.6.2 Typical Command Execution Times\n\nThe EEL command execution times can depend on several factors as for instance the system clock frequency, the flash memory programming mode (full speed or wide voltage), the current pool constellation, the number and size of the utilized EEL variables and the period between the handler calls. The typical command execution time examples listed in Table 5-9 have been measured based on the following scenario:\n\n- The EEL_Handler is called continuously after issuing the command via EEL_Execute until it is completed.\n- The system clock frequency is 20 MHz.\n- The flash memory programming mode operates in full speed mode.\n- All measurements have been performed with the same EEL descriptor (variable set) as it is used in the example descriptor provided with the library. Descriptor properties which have an influence on the execution time are mentioned in the column “Command-specific condition” in the table.\n- All commands are finished successfully.\n- Further command-specific conditions are listed in the table.\n\nTable 5-9: Typical command execution time examples of the Tiny EEL V1.00\n\n<table>\n<thead>\n<tr>\n<th>Command</th>\n<th>Command-specific condition</th>\n<th>Typical command execution time [µs]</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>Format</td>\n<td>3 EEL blocks, all non-blank</td>\n<td>19100</td>\n</tr>\n<tr>\n<td>Startup</td>\n<td>3 EEL blocks, last block active and almost full, 8 EEL variables.</td>\n<td>1245</td>\n</tr>\n<tr>\n<td>Shutdown</td>\n<td>-</td>\n<td>12</td>\n</tr>\n<tr>\n<td>Refresh</td>\n<td>3 EEL blocks, no excluded blocks, 8 variables (all written) with a total size of 305 bytes (example descriptor)</td>\n<td>41057</td>\n</tr>\n<tr>\n<td>Verify</td>\n<td>The internal verify (see FDL) passes for the whole active block</td>\n<td>4073</td>\n</tr>\n<tr>\n<td>Write</td>\n<td>variable size 2 bytes (type_A from example descriptor), variable has been written before</td>\n<td>760</td>\n</tr>\n<tr>\n<td></td>\n<td>variable size 4 bytes (type_C from example descriptor), variable has been written before</td>\n<td>865</td>\n</tr>\n<tr>\n<td></td>\n<td>variable size 10 bytes (type_F from example descriptor), variable has been written before</td>\n<td>1179</td>\n</tr>\n<tr>\n<td></td>\n<td>variable size 255 bytes (type_Z from example descriptor), variable has been written before</td>\n<td>14028</td>\n</tr>\n<tr>\n<td>Read</td>\n<td>variable size 2 bytes (type_A from example descriptor), variable has been written before</td>\n<td>38</td>\n</tr>\n<tr>\n<td></td>\n<td>variable size 4 bytes (type_C from example descriptor), variable has been written before</td>\n<td>39</td>\n</tr>\n<tr>\n<td></td>\n<td>variable size 10 bytes (type_F from example descriptor), variable has been written before</td>\n<td>43</td>\n</tr>\n<tr>\n<td></td>\n<td>variable size 255 bytes (type_Z from example descriptor), variable has been written before</td>\n<td>215</td>\n</tr>\n</tbody>\n</table>\n\nNote:\nThe timings listed in Table 5-9 are only example measurements and no specification. Deviations have to be expected based on the target setup and situation.\n5.4 Library Setup\n\nThe Tiny EEL can be configured and adapted to a certain degree in order to fit the requirements of the user application. Most important to mention here is the possibility to configure an application-specific set of variables of different sizes. The details how to perform this setup are described in the following sections.\n\n5.4.1 EEL Pool Configuration\n\nAs already described in Section 2.2, the Data Flash can be separated in an FDL and an EEL pool which coexist and can be used independently. The actual number of blocks assigned to EEL and FDL can be configured in the descriptor of the FDL. Please have a look at the user manual of the Tiny FDL (FDL type T02) for details.\n\nPlease note that the minimum number of EEL blocks required for operation is 2.\n\nIncreasing the number of available EEL blocks does not increase the capacity of the variable set that can be used with the Tiny EEL (see also Section 5.4.3). However, it makes sense to assign more than two blocks to the EEL pool. This way, hot spots on one block are reduced and wear leveling is improved. On the one hand, this means that the number of erases for one block is effectively reduced increasing the lifetime of the device. On the other hand, it enables a larger number of variable updates (writes) during the device life cycle.\n\nDeriving the actual number of required EEL blocks for a certain scenario (application and required device lifetime) is a nontrivial task, which is directly related to the endurance of Data Flash and detailed in the following section.\n\nIn this context of flash endurance, please recall that whenever the number of non-excluded blocks falls below 2 (i.e. there is only one non-excluded block left), write access and refresh is not possible anymore. However, read access can still be performed (c.f. Section 2.3.1). A reanimation of the library can only be attempted by a format of the pool (see Section 4.3.4).\n\n5.4.2 Endurance Calculation\n\nEvery write operation of a new EEL variable instance occupies space in the Data Flash. Whenever the active block is full, the current variable set needs to be copied to a new block by means of the refresh operation during which the target block is erased (see also Section 2.3.1).\n\nThis process is repeated many times over the device lifetime. However, the endurance of the Data Flash blocks regarding the number of erase cycles is limited. Hence, it is necessary to calculate the application-specific number of erase cycles required over the device lifetime and to ensure that the specified Data Flash endurance is not exceeded.\n\nRenesas provides an endurance calculation sheet which can be filled with the different data sets sizes and the required write cycles. The sheet can estimate the expected number of Flash erase cycles and indicate an exceedance of the Data Flash specification. Thereby, the number of available EEL blocks has a major impact the overall endurance of the pool. By using varying numbers of EEL blocks for the calculation, the required number of EEL blocks can be derived for the target application scenario.\n\nNote:\nThe endurance calculation sheet is a very helpful tool. However, please note that the result is only an estimate and the sheet cannot produce absolutely accurate numbers. The exact endurance depends on additional constraints—like for instance the write sequence of the variables—which are not captured by the sheet. Therefore, any result of the endurance calculation sheet must be confirmed in the actual user application.\n\nThe calculation sheet can be obtained from the Renesas Flash support, which can be contacted via Email at the following address: application_support.flash-eu@lm.renesas.com.\n5.4.3 EEL Variable Configuration\n\nThe characteristics of the precompiled EEL can be configured by the user in two source files:\neel_descriptor.h and eel_descriptor.c (eel_descriptor.inc and eel_descriptor.asm for assembler).\n\nIn the header file eel_descriptor.h, the developer has to set the number of EEL variables to be handled by\nthe library by means of the constant EEL_VAR_NO. Any integer value from 1 to 64 is allowed. If this\nmaximum number of variables is not sufficient in your case, please contact the Renesas support in order\nto find the proper solution for your application scenario at application_support.flash-eu@lm.renesas.com.\n\n```c\n#define EEL_VAR_NO 8\n```\n\nThe actual set of variables is defined in eel_descriptor.c by means of the constant array eel_descriptor.\nThe first element of the array represents the number of defined variables. This element is followed by the\nsize of each variable which may be between 1 and 255 bytes. Thereby the index within the array matches\nthe corresponding variable ID. As a result the first EEL variable ID is always ‘1’. A user-specified ID as it\nis featured in the EEL Type T01 is not supported by the Tiny EEL. The variable list needs to be zero\nterminated in the last element.\n\n```c\n__far const eel_u08 eel_descriptor[EEL_VAR_NO+2] =\n{\n (eel_u08)(EEL_VAR_NO), /* variable count */ \\\n (eel_u08)(sizeof(type_A)), /* id=1 */ \\\n (eel_u08)(sizeof(type_B)), /* id=2 */ \\\n (eel_u08)(sizeof(type_C)), /* id=3 */ \\\n (eel_u08)(sizeof(type_D)), /* id=4 */ \\\n (eel_u08)(sizeof(type_E)), /* id=5 */ \\\n (eel_u08)(sizeof(type_F)), /* id=6 */ \\\n (eel_u08)(sizeof(type_X)), /* id=7 */ \\\n (eel_u08)(0x00), /* zero terminator */ \\\n};\n```\n\nClearly, the overall consumption of the variable instances may not exceed the available space in the\nactive block. Hence the defined variable set needs to fulfill the following relation in order to maintain\noperational:\n\n\\[\n2(N+1) + \\sum s(i) + \\text{MAX}(s(i)) \\leq 1014\n\\]\n\nwhere \\( N \\) is the number of variables and \\( s(i) \\) is the size of variable \\( i \\). However, it is strongly recommended\nnot to exhaust the space as this leads to very frequent and costly refreshing of the pool (in the worst case\nafter each variable write). As a rule of thumb, the variable set should fulfill the following relation:\n\n\\[\n2(N+1) + \\sum s(i) \\leq 507\n\\]\n\nIf the variable setup is exceeding this limit, it can be considered to move seldom changed data from the\nEEL to the FDL pool (where it has to be managed by the developer). Depending on the scenario, the EEL\ntype T01 might also be an alternative as it can handle a larger amount of data. In case of any doubts\nwhich library suits your application scenario best, please contact the Renesas support at\napplication_support.flash-eu@lm.renesas.com.\n\n**Note:**\nIn case the variable setup is changed, it is imperative to format the EEL pool before continuing the\noperation on the pool (i.e. before startup).\nThe only exception to this rule is that appending variables to the existing list is allowed as this does not\nchange the ID and size of the existing variables.\n5.4.4 EEL Variable Initialization\n\nBefore being able to regularly use the Data Flash for EEPROM emulation, the EEL pool must be formatted and—depending on the application—be filled with initial values for the EEL variables. This can be done using different approaches. Two very common ways are presented in the following:\n\n- The application itself executes the format operation and then writes initial instances of the variables. As the format operation deletes all data, it needs to be carefully considered in this scenario how to prevent accidental pool formatting by the application.\n- A serial programming tool (e.g. PG-FP5) or debugger is used to program the Data Flash in the same flow that also programs the Code Flash.\n\nFor the later approach (using a programming tool or a debugger), a hex file is required which contains the Data Flash content (i.e. the complete EEL pool in raw format). This content can be gained by:\n\n- dumping the content of the Data Flash with an already formatted EEL pool into a hex file using a serial programming tool or the debugger, or by\n- using a tool chain of Data Flash Converter and/or Data Flash Editor to convert EEL variable values into a hex file.\n\nData Flash Converter and Data Flash Editor can be obtained from the following URLs (including dedicated user manuals):\n\n\nPlease note that the Tiny EEL is supported only by the Data Flash Converter since version V6.00 and by Data Flash Editor versions V4.00 or higher.\n\n5.4.5 Distributing Data between FDL and EEL\n\nAs already described in Section 2.2, the Data Flash can be separated in an FDL and an EEL pool which coexist and can be used independently. As a consequence, the developer has the freedom to choose for each set of data whether to manage it himself in the FDL pool or to assign it to an EEL variable.\n\nIn general, data which is constant over the lifetime of the device (or is updated very seldom), is placed best in the FDL pool. This enables early access after power up (before the EEL is started up). However, the developer has to take care himself of data management and reset robustness. The overall size of the utilizable FDL pool is thereby manly limited by the number of blocks in the Data Flash.\n\nData which is updated frequently is usually managed best in the EEL pool. A variable-oriented update of data is provided in a way that wear-leveling and reset-robustness considered. However, the utilizable space is limited (only one active block).\n\n5.4.6 Building Efficient EEL Variable Sets\n\nWhenever defining variables to be used with the EEL, the following two main characteristics should be considered:\n\n- A variable instance always creates additional administrative usage of the active block by means of a reference entry of two bytes. As a consequence, many small variables lead to a reduction of space utilizable for data.\n- When updating a variable (write), the whole data of the variable needs to be written in the empty space of the active block. Hence, it is inefficient to assemble several small variables which are updated independently into a larger single variable.\n\nTherefore, variables which are typically updated concurrently (like for instance data and checksum) should be assembled in a single EEL variable.\n\n5.5 Practical Aspects of Library Usage\n\nThe following sections collect assorted aspects of practical usage of the Tiny EEL.\n5.5.1 When to use EEL_Handler and FDL_Handler\n\nOne of the most typical usage scenarios for the Tiny EEL is that also the Tiny FDL is used with its own assigned flash pool. Both libraries provide a handler to drive pending commands and update the status of the corresponding request structure. On top of that, the EEL_Handler might even execute the FDL_Handler, when the EEL has issued an FDL command on its own and is waiting for the result. However, it is not guaranteed that every EEL_Handler call also results in an FDL_Handler call. Therefore, it is not sufficient to only call the EEL_Handler in a mixed FDL/EEL application.\n\nNevertheless, both FDL and EEL are robust against calls of the opposite handler which could only lead to a completion of the currently running command. Therefore, the application designer should stick to a very simple rule:\n\nWhen issuing a command from a scope, always call the handler corresponding to the issued command from that scope in order to finish the command.\n\nThereby, it can be guaranteed that commands do finish, although EEL commands can be interrupted by FDL commands and EEL commands drive running FDL commands by means of the EEL_Handler.\n\n5.5.2 EEL_Handler Calls\n\nOnce initiated EEL commands need to be driven forward by successive handler calls. The frequency of these handler calls does have an impact on the EEL operation performance and needs to be adapted to the target application.\n\nIn the following, different approaches for calling the EEL_Handler are compared with respect to their advantages and disadvantages:\n\n- **Calling EEL_Handler repeatedly after issuing a command execution**: This approach is also utilized in most of the code examples you can find in this manual. Typically realized in a loop waiting for the operation status not to be busy anymore, this approach results in the best EEL operation performance. However, the CPU is fully loaded and blocked for other tasks as long as the EEL command is being executed. This approach can also be seen as using the library with a blocking function-oriented interface.\n\n- **Calling EEL_Handler in a timed task**: By calling the EEL_Handler periodically, EEL commands can be driven forward while other tasks are processed by the CPU. The period between the handler calls can have significant impact on the EEL operation performance. Shorter calling intervals result in better EEL performance, but also increase the CPU load by the EEL. Due to this tradeoff, a general advice for the calling interval cannot be given. It needs to be analyzed and tailored individually for each target application.\n \n However, selecting a calling interval shorter than the typical command execution time for a single-byte FDL write command (see the documentation of RL78 FDL T02) does not improve the EEL performance significantly and should be avoided.\n\n- **Calling EEL_Handler in the idle task**: If it is ensured that the idle task is called often enough, this method might result in a good EEL performance, as the handler can be called continuously.\n \n However, this approach is not deterministic in case of a high CPU load by the application itself.\n\nDue to the individual requirements of each application, a general advice for selecting a strategy to call the EEL_Handler cannot be given. Please also consider that mixtures of the above mentioned approaches can be meaningful depending on the target scenario.\n\n**Note 1:**\nWhen evaluating concepts for calling the EEL_Handler, please be aware that all FDL/EEL functions are not re-entrant. That means it is not allowed to call FDL/EEL functions from interrupt service routines while any FDL/EEL function is already running.\n\n**Note 2:**\nIn contrast to the RL78 EEL T01, the Tiny EEL does not have any background processing for pool maintenance. Hence, it is only mandatory to call the EEL_Handler as long as there is an unfinished EEL command. It is not necessary to call the EEL_Handler regularly for pool maintenance. However, in case there is nothing to process, the EEL_Handler consumes a few clock cycles only and does no harm.\n5.5.3 When to issue a Refresh\n\nIn general, there are two strategies a developer can follow with respect to the ever reoccurring EEL refresh:\n\n- **Refresh on error during write:** Whenever a write command results in an EEL_ERR_POOL_FULL error, issue a refresh and restart the write command. Thereby, the EEL pool is used in an efficient way with respect to keeping the number of erase cycles low. The drawback of this approach is the fact that writing an EEL variable can require a time consuming flash block erase which can be a problem in time-critical scenarios.\n\n- **Pre-emptive refresh based on free-space analysis:** By means of the function EEL_GetSpace, the developer can regularly monitor the current free space in the active block and issue the refresh when the library space is getting short and there is sufficient processing time for it (including the erase of the new active block). Thereby, it can be guaranteed that a write does not result in a time-consuming refresh (i.e. block erase). The drawbacks of this approach are on the one hand an increased administrative effort in the user application, and on the other hand a more frequent occurrence of block erasures which can result in a reduction of the overall lifetime of the device.\n\nThe developer should analyze his application carefully to choose one of these two methods. Even a mixture of both approaches in a single application could be considered.\n\n5.5.4 Using the Standby and Abort Feature of the Tiny FDL\n\nThe Tiny FDL offers a standby/wakeup feature in order to temporarily turn off the data flash (e.g. for energy savings). This mechanism is transparent for the usage of the EEL, meaning that it is allowed to even interrupt running EEL commands temporarily by calling FDL_StandBy.\n\nPlease note however, that setting the FDL into standby will prevent also EEL command execution. However, new commands will not be rejected but simply not completed in this case. This means that it is not possible to check through the EEL API whether the FDL has been sent to standby. The developer has to use FDL functions in order to do this.\n\nAfter the execution of FDL_WakeUp, the EEL will continue the pending command executions with the next EEL_Handler call.\n\n**Note:**\nPlease read the Tiny FDL user manual for a more detailed description of the standby/wakeup feature and its usage.\n\nSimilarly, the abort feature of the Tiny FDL can be used transparently when the EEL is used. In case the EEL has issued an FDL erase command (e.g. during refresh), it is not forbidden to abort this command via FDL_Abort. In that case the EEL will resume the erase the next time the EEL_Handler is called. Considering also the reset robustness of the Tiny EEL, it is explicitly allowed to use FDL_Abort in emergency situations (e.g. in case of a voltage drop) in order to ensure a fast saving of important data.\n5.5.5 Using the Tiny EEL in Operating Systems\n\nAs many time-consuming flash operations are performed in the background and only their progress is only checked by means of a request-response mechanism, the Tiny FDL and EEL can be efficiently used inside an operating system.\n\n**Note:**\nPlease read the cautions for the EEL described in Chapter 6 and also the cautions chapter of the Tiny FDL manual carefully before utilizing the Tiny FDL and Tiny EEL in an operating system.\n\nFIGURE 5-1: SCHEMATIC ILLUSTRATION OF TINY EEL INTEGRATION INTO AN OPERATING SYSTEM\n\nFigure 5-1 illustrates a schematic example how to integrate the Tiny EEL into an operating system. Please note that this is only an abstract example to show the principle of the mechanism.\n\nThree different types of tasks have to be distinguished:\n\n- **Requesting tasks:** Requesting tasks issue any FDL or EEL command via FDL_Execute and EEL_Execute, respectively, assuming that the command execution will be finished by the IDLE task. In the example, task 1 issues an FDL command, while an EEL command is started from task 2.\n\n- **IDLE task:** The IDLE task (task 4 in the example) is used to finish any running FDL or EEL command by means of FDL_Handler and EEL_Handler calls. (It is assumed here that the idle task is executed whenever no other task is running.) Please note that it is necessary to call both handlers form such a function in order to ensure the completion of both types of commands.\n\n- **Emergency task:** This task is triggered in an emergency situation as for instance in case of a voltage drop in order to save important data before the device is powered off. In the shown example, task 3 is the emergency task. In such a task it is important to complete the issued command as fast as possible by repeated handler calls. Please note that the example uses the FDL for writing emergency data. It is recommended to do so as the processing time for a write command is less compared to the EEL and contingent and time-consuming refresh can be avoided.\n\n**Note:**\nFor emergency tasks, it can be a good idea to take advantage of the abort feature of the Tiny FDL in order to avoid lengthy erase processes in such a situation. Please see Section 5.5.4 and the Tiny FDL user manual for details.\n5.5.6 Reset Robustness Considerations\n\nIn general, the sequences of EEL commands modifying the EEL pool have been designed in a way that incomplete command executions are detected during the next startup and one valid set of EEL data can always be restored.\n\nHence, during normal operation, there will be no loss of EEL data due to reset. Nevertheless, please be aware that depending on the progress of the interrupted last command, the old or the new variable set will be active after restarting the library.\n\nThere is one exception to this rule: The format command is not robust against resets. In case a reset occurs during a format, there is a chance that the EEL pool is coincidentally valid and will be accepted during the next startup. In order to minimize this risk, all blocks are invalidated as a first step during a pool format. However, please ensure to always finish a once started format command.\n\nPlease note that this limitation is not severe in the typical use case as a format command destroys all EEL variable content and is therefore usually executed once at the beginning of a product lifetime.\n\n5.5.7 Pitfalls with Request Variables declared in a local Scope\n\nThe request-response oriented command execution of the Tiny EEL enables a comfortable way of issuing different commands quasi independently from different scopes of the user application. The developer should thereby always be aware that the request data structure is updated later by the library via handler calls. Therefore, it is imperative to ensure the existence of the data structure as long as the command is being processed.\n\nThis is of special importance when using local C request variables which are placed in the stack. When the application leaves the scope of such a local variable, the reserved space on the stack is deallocated and probably reused for other variables or return addresses. When an EEL command is finished in such a situation, this new data is overwritten, leading to unpredictable behavior of the application. Such situations are often hard to detect and debug. Hence, the developer should always be pay special attention to the scope of the used request variables.\nChapter 6 Cautions\n\nBefore starting the development of an application using the Tiny EEL, please carefully read and understand the following cautions:\n\n- The library code and constants must be located completely in the same 64KB flash page.\n - For CA78K0R compiler, the library takes care in the code to define these sections with UNIT64KP relocation attribute.\n - For IAR V1.xx and IAR V2.xx compiler, the user has to ensure that the linker file specifies the Flash page size equal to 64KB when defining FDL_CODE, FDL_CNST, EEL_CODE and EEL_CNST sections.\n - For GNU compiler, the user shall take care that FDL_CODE, FDL_CNST, EEL_CODE and EEL_CNST sections are not mapped across any boundary of 64KB Flash page.\n - For CC-RL compiler, the library takes care in the code to define these sections with TEXTF_UNIT64KP relocation attribute.\n- The FDL library initialization by means of FDL_Init must be performed before the execution of FDL_Open, FDL_Close, FDL_Handler, FDL_Execute, FDL_Abort, FDL_StandBy, FDL_WakeUp and all EEL functions.\n- The EEL library initialization by means of EEL_Init must be performed before the execution of EEL_Open, EEL_Close, EEL_Execute, EEL_Handler, EEL_GetDriverStatus, EEL_GetSpace.\n- It is not allowed to read the data flash directly (meaning without FDL) during a command execution of the FDL/EEL.\n- Do not execute the STOP or HALT instruction during the execution of the Tiny FDL/EEL without driving the library into standby first.\n- The watchdog timer does not stop during the execution of the Tiny FDL/EEL.\n- Each request variable must be located at an even address.\n- Before executing any command, all members of the request variable must be initialized once. If there are any unused members in the request variable, please set arbitrary values to these members. Otherwise, a RAM parity error may cause a reset of the device. For details, please refer to the document “User’s Manual: Hardware” of your RL78 product.\n- All functions are not re-entrant. That means it is not allowed to call FDL/EEL functions from interrupt service routines while any FDL/EEL function is already running.\n- Task switches, context changes and synchronization between FDL functions:\n - All FDL/EEL functions depend on FDL/EEL global available information and are able to modify this information. In order to avoid synchronization problems, it is necessary that at any time only one FDL/EEL function is executed. So, it is not allowed to start an FDL/EEL function, then switch to another task context and execute another FDL/EEL function while the other one is not yet finished.\n - Example for a forbidden sequence:\n 1. Task 1: Start an FDL/EEL operation with FDL_Execute/EEL_Execute.\n 2. Interrupt the execution and switch to task 2, executing FDL_Handler/EEL_Handler.\n 3. Return to task 1 and finish the FDL_Execute/EEL_Execute function.\n- After the execution of FDL_Close/EEL_Close, all requested/running commands will be aborted and cannot be resumed. The user has to take care that all running commands are finished before calling FDL_Close/EEL_Close.\n- It is not possible to modify the Data Flash in parallel to a modification of the Code Flash.\n- The internal high-speed oscillator must be started before using the FDL/EEL.\n• Do not locate any function arguments, data buffers or stack to the short address area from 0xFFE20 to 0xFFEFF.\n\n• When the Data Transfer Controller (DTC) is used during control of data flash, do not locate the RAM area for the DTC to the short address area from 0xFFE20 to 0xFFEFF.\n\n• Do not use the RAM area used by the Tiny FDL/EEL (including the prohibited RAM area) before both libraries have been closed.\n\n• The reset robustness of each written EEL instance is inherently provided by the Tiny EEL. However, the data itself is not secured directly by any checksum. In case the user application destroys the data buffer during the write process or by any other accident, the EEL will not be able to detect this and will return wrong data values when reading this instance. If your scenario requires such type of data protection, please assemble each eel instance from data and checksum and perform consistency checks after each read access manually.\n\n• In case of an accidental write to the eel pool (e.g. due to stack runaway, misuse of FDL etc.) the following scenarios may occur:\n • In case of damaged block flags the whole eel pool could become inconsistent. As a result, all valid instances could be lost.\n • In case of damaged instance entry\n • all or only a part of instances could become invalid.\n • old instances could become valid.\n\n• It is not allowed to continue the execution of the EEL in case the FDL or EEL descriptor has been changed. In such a situation, the initialization of the FDL and EEL shall be performed as well as the EEL pool format via the EEL_CMD_FORMAT command.\n\n• Do not destroy the request structure (eel_request_t) during command execution.\n\n• Do not operate the data flash control register (DFLCTL) during execution of the EEL.\n\n• When using an assembler of the CC-RL compiler from Renesas Electronics, the hexadecimal prefix representation (0x..) cannot be mixed together with the suffix representation (.H). Specify the representation method by editing the symbol definition in eel_types.inc to match the user environment.\n\n eel_types.inc\n \n \\[ \\_EEL\\_TYPES\\_INC\\_BASE\\_NUMBER\\_SUFFIX\\_SET\\_1 \\]\n \n When symbol \"\\_EEL\\_TYPES\\_INC\\_BASE\\_NUMBER\\_SUFFIX\" is not defined (initial state), the prefix representation will be selected.\n\n eel_types.inc\n \n \\[ \\_EEL\\_TYPES\\_INC\\_BASE\\_NUMBER\\_SUFFIX\\_SET\\_1 \\]\n \n When symbol \"\\_EEL\\_TYPES\\_INC\\_BASE\\_NUMBER\\_SUFFIX\" is defined, the suffix representation will be selected.\n\n• Additional cautions on using the Tiny EEL for IAR V2.xx.\n\n • Library code and constants must be located completely in the same 32KB memory range.\n\n • The version string provided by the flash library includes the information on the supported compiler. The string indicates that the supported compiler is CC-RL because the library file for IAR V2.xx is identical to the one for CC-RL.\n\n • If you wish to use a linker configuration file included in the IAR V2.2x compiler (instead of a sample linker configuration file in the flash library package), specify flash libraries sections with special names for Renesas objects (R_TEXTF_UNIT64KP, R_SBSS) in the linker configuration file.\n\n e.g.)\n \n ro section FDL_CODE -> ro code R_TEXTF_UNIT64KP section FDL_CODE\n ro section EEL_CODE -> ro code R_TEXTF_UNIT64KP section EEL_CODE\n rw section FDL_SDAT -> rw data R_SBSS section FDL_SDAT\n rw section EEL_SDAT -> rw data R_SBSS section EEL_SDAT\nNote:\nSections FDL_CNST and EEL_CNST do not require special names for Renesas objects since these sections are generated from the sample source files (eel_descriptor.c, fdl_descriptor.c). Simply declare these flash libraries sections in a linker configuration file as if they are normal sections.\n\n e.g.)\n ro section FDL_CNST\n ro section EEL_CNST\n## Revision History\n\n<table>\n<thead>\n<tr>\n<th>Chapter</th>\n<th>Page</th>\n<th>Description</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td>All</td>\n<td></td>\n<td>Rev. 1.00:</td>\n</tr>\n<tr>\n<td></td>\n<td></td>\n<td>Initial document</td>\n</tr>\n<tr>\n<td>All</td>\n<td></td>\n<td>Rev. 1.01:</td>\n</tr>\n<tr>\n<td>4.1.6</td>\n<td>31</td>\n<td>Section added describing the variable eel_descriptor</td>\n</tr>\n<tr>\n<td>5.4.1</td>\n<td>70</td>\n<td>Paragraph about flash endurance considerations added</td>\n</tr>\n<tr>\n<td>5.4.2</td>\n<td>70</td>\n<td>Section for endurance calculation added</td>\n</tr>\n<tr>\n<td>5.4.4</td>\n<td>72</td>\n<td>Section added describing EEL variable initialization</td>\n</tr>\n<tr>\n<td>5.5.2</td>\n<td>73</td>\n<td>Section on EEL_Handler calls added</td>\n</tr>\n<tr>\n<td>All</td>\n<td></td>\n<td>Corrected typos, updating links for download page</td>\n</tr>\n<tr>\n<td>All</td>\n<td></td>\n<td>Rev 1.02: Document type changed from Application Note to User Manual</td>\n</tr>\n<tr>\n<td>4.1</td>\n<td>27</td>\n<td>Rev. 1.03: Added type description notes for GNU</td>\n</tr>\n<tr>\n<td>4.2</td>\n<td>34</td>\n<td>Added description for GNU API</td>\n</tr>\n<tr>\n<td>5.2</td>\n<td>68</td>\n<td>Extend file structure for GNU</td>\n</tr>\n<tr>\n<td>5.3.1</td>\n<td>69</td>\n<td>Added resource consumption for GNU</td>\n</tr>\n<tr>\n<td>5.3.5</td>\n<td>70</td>\n<td>Added register bank usage for GNU</td>\n</tr>\n<tr>\n<td>6</td>\n<td>80</td>\n<td>Explanation added how library can be mapped in the same 64K flash page for each compiler</td>\n</tr>\n<tr>\n<td>All</td>\n<td></td>\n<td>Rev. 1.04: Added description for CC-RL API</td>\n</tr>\n<tr>\n<td>4.2</td>\n<td>34</td>\n<td>Added description for CC-RL API</td>\n</tr>\n<tr>\n<td>4.2.7</td>\n<td>47</td>\n<td>Added note to description of EEL_GetSpace</td>\n</tr>\n<tr>\n<td>5.2</td>\n<td>71</td>\n<td>Extend file structure for CC-RL</td>\n</tr>\n<tr>\n<td>5.3.1</td>\n<td>72</td>\n<td>Added resource consumption for CC-RL</td>\n</tr>\n<tr>\n<td>5.3.5</td>\n<td>73</td>\n<td>Added register bank usage for CC-RL</td>\n</tr>\n<tr>\n<td>6</td>\n<td>82</td>\n<td>Extend cautions for CC-RL</td>\n</tr>\n<tr>\n<td>all</td>\n<td>all</td>\n<td>Renesas (REN) Compiler renamed to CA78K0R</td>\n</tr>\n<tr>\n<td>5.3.1</td>\n<td>71</td>\n<td>Rev. 1.05: Corrected stack consumption for CC-RL compiler.</td>\n</tr>\n<tr>\n<td>4.2</td>\n<td>33</td>\n<td>Rev. 1.10: Added description for IAR V2.xx API</td>\n</tr>\n<tr>\n<td>5.2</td>\n<td>71</td>\n<td>Extend file structure for IAR V2.xx</td>\n</tr>\n<tr>\n<td>5.3.1</td>\n<td>73</td>\n<td>Added resource consumption for IAR V2.xx</td>\n</tr>\n<tr>\n<td>5.3.5</td>\n<td>75</td>\n<td>Added register bank usage for IAR V2.xx</td>\n</tr>\n<tr>\n<td>6</td>\n<td>84</td>\n<td>Extend cautions for IAR V2.xx</td>\n</tr>\n</tbody>\n</table>\nEEPROM Emulation Library"}}}],"truncated":false,"partial":false},"paginationData":{"pageIndex":0,"numItemsPerPage":100,"numTotalItems":22671,"offset":0,"length":100}},"jwt":"eyJhbGciOiJFZERTQSIsImtpZCI6IjVHZDBvd0g5MTM2eDZjc1FvbE1zcktNWUZoRVFoUm5PVVVybEpjOUhaUEEifQ.eyJyZWFkIjp0cnVlLCJwZXJtaXNzaW9ucyI6eyJyZXBvLmNvbnRlbnQucmVhZCI6dHJ1ZX0sImlhdCI6MTc4NDMzMjM1NywianRpIjoiNDViM2UyYjYtZjk3My00N2Y4LWJhMmQtMzA1YWU0ZWYyMjU0Iiwic3ViIjoiL2RhdGFzZXRzL21saW5tZy9kb2xtYTNfbG9uZ21pbm9fbWl4LTEwMEItMTEyNS1zYWZlLXRvLWxvYWQiLCJleHAiOjE3ODQzMzU5NTcsImlzcyI6Imh0dHBzOi8vaHVnZ2luZ2ZhY2UuY28ifQ.eGvNgQcgAs9knnPL2G3Zjjftc-JwGVuBuoE0LNdi23pAmKqcKr5j7w_LucIBWSXpi5sFK4GT3Gff2-SDxAgtCw","displayUrls":true,"splitSizeSummaries":[{"config":"default","split":"train","numRows":22671,"numBytesParquet":1201011708}]},"discussionsStats":{"closed":0,"open":1,"total":1},"fullWidth":true,"hasGatedAccess":true,"hasFullAccess":true,"isEmbedded":false,"savedQueries":{"community":[],"user":[]}}">
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cb2d52c319c8b64ac30f4ec960db4a33497b5676 | Dependability analysis of web services
Looker, Nik
How to cite:
Looker, Nik (2006) Dependability analysis of web services, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/2888/
Use policy
The full-text may be used and/or reproduced, and given to third parties in any fo... |
09e6c2cdc0983eaa061c7ff97488b52d03a5b1d2 |
Jim Saito, Ames Research Center, Moffett Field, California
January 1987
# CONTENTS
<table>
<thead>
<tr>
<th>Section</th>
<th>Page</th>
</tr>
</thead>
<tbody>
<tr>
<td>LIST OF SYMBOLS</td>
<td>v</td>
</tr>
<tr>
<td>SUMMARY</td>
<td>1</td>
</tr>
<tr>
<td>INTRODUCTION</td>
<td>1</td>
</tr>
<tr>
<td>DFCSVL OVERVIEW</td>... |
1bbf25dbae0c842d5951f714c240b3203cfa0f5e | A Basic Linear Algebra Compiler for Embedded Processors
Master Thesis
Nikolaos Kyrtatas
April 15, 2014
Advisors: Prof. Dr. Markus Püschel, Daniele Spampinato
Department of Computer Science, ETH Zürich
To my grandfather,
who understands computers better than me.
Abstract
In many fields, such as signal processing, co... |
c3833a8c445773d74e8e770e07b078d9ba64147e | FLEXIBLE PACKAGING METHODOLOGIES FOR RAPID DEPLOYMENT OF CUSTOMISABLE COMPONENT-BASED DIGITAL LIBRARIES
A dissertation submitted to the Department of Computer Science, Faculty of Science at the University of Cape Town in partial fulfilment of the requirements for the degree of
MASTER OF SCIENCE
in
Computer Science
—... |
10590a91ee4cce9a222b4629fd9fca53b518fb16 | Contents
1 Getting started 1
1.1 Prerequisites ............................................. 1
1.2 Installation ............................................. 1
2 Configuration of UNICORE/X 3
2.1 Overview of the main configuration options ................. 3
2.2 Config file overview .......................... |
58f56b103619027510a8c1cbd4cff24dc88c1798 | Oracle® VM
Release Notes for 3.3.3
# Table of Contents
Preface ................................................................................................................................................ vii
1 Audience ................................................................................................ |
609cc4a3ab534e0101a8b8afdf9f8bf30f6c4290 | A type-sound calculus of computational fields
This is the author's manuscript
Original Citation:
A type-sound calculus of computational fields / Damiani, Ferruccio; Viroli, Mirko; Beal, Jacob. - In: SCIENCE OF COMPUTER PROGRAMMING. - ISSN 0167-6423. - 117(2016), pp. 17-44.
Availability:
This version is available htt... |
264e523246846e664d910a62353a4c81f3acba7c | Partial Verification Results
Doctoral Thesis
Author(s):
Wüstholz, Valentin T.
Publication date:
2015
Permanent link:
https://doi.org/10.3929/ethz-a-010538908
Rights / license:
In Copyright - Non-Commercial Use Permitted
Partial Verification Results
A thesis submitted to attain the degree of
Doctor of Sciences of... |
57c76b82ba75e62c53feef8a381dd3986707d6c1 | SUPPORT FOR MODEL COUPLING: AN INTERFACE-BASED APPROACH
by
THOMAS FRANCIS BULATEWICZ, JR.
A DISSERTATION
Presented to the Department of Computer and Information Science and the Graduate School of the University of Oregon in partial fulfillment of the requirements for the degree of Doctor of Philosophy
June 2006
"S... |
05bd06d65c49797eaddd5177d2c070ed7ff20a73 | ## Contents
### Table of Contents
1. **Getting Started**
1.1 Introduction ................................................. 6
1.2 Making sure you're ready to go ................................. 6
1.3 Quick Start .................................................. 6
1.4 Components of BSV Release ..... |
430e56120af0e217c3b8f71294d07ae292ecbafe | ACCESSIBLE ACCESS CONTROL: A VISUALIZATION SYSTEM FOR ACCESS CONTROL POLICY MANAGEMENT
Man Wang
Michigan Technological University, manw@mtu.edu
Copyright 2019 Man Wang
Recommended Citation
https://digitalcommons.mtu.edu/etdr/841
Follow this and additional works at: https://digitalcommons.mtu.edu/etdr
Part of the E... |
b80501e9ecdd870fe871837aa9afdcd286d18383 | GUI Design for Android Apps
What You'll Learn:
• Key aspects of why UI and UX design for embedded systems is different than for desktops
• Troubleshooting UI design issues
• Understanding how key concepts such as state transition, Context class, and intents work
• How to use the interface app design tools provided by ... |
5068bb1ecf919eb5fc287660bf6d9f2975bc538b | E. De Angelis, F. Fioravanti,
A. Pettorossi, M. Proietti
SEMANTICS-BASED GENERATION OF
VERIFICATION CONDITIONS VIA PROGRAM
SPECIALIZATION
R. 9 2016
Emanuele De Angelis – DEC, University “G. d’Annunzio”, Pescara, Italy, and Istituto di
Analisi dei Sistemi ed Informatica “Antonio Ruberti” del CNR, Via dei Taurini 15, ... |
119e6f01a902793d61edeb2d7bd45afd4c21e991 | An Efficient SNARK for Field-Programmable and RAM Circuits
Jehyuk Jang* and Jamie Judd†
Tokamak Network
March 2024
Abstract – The advancement of succinct non-interactive argument of knowledge (SNARK) with constant proof size has significantly enhanced the efficiency and privacy of verifiable computation. Verifiable ... |
7d0d81cfcb732e8c332c28a1c5c9993bbd4dc24a | ## Revision History
The following table shows the revision history for this document.
<table>
<thead>
<tr>
<th>Date</th>
<th>Version</th>
<th>Revisions</th>
</tr>
</thead>
<tbody>
<tr>
<td>04/05/2017</td>
<td>2017.1</td>
<td>Updated content based on the new Vivado IDE look and feel. Modified Figure 1-1. Additional IP... |
ad6d30bbf4ee3f28f3fd735d75b8d307121aae9a | Automated Verification of Weak Equivalence within the SMODELS System*
TOMI JANHUNEN and EMILIA OIKARINEN
Helsinki University of Technology
Department of Computer Science and Engineering
Laboratory for Theoretical Computer Science
P. O. Box 5400, FI-02015 TKK, Finland
(e-mail: Tomi.Janhunen@tkk.fi, Emilia.Oikarinen@tk... |
5ea421b9f8a138b1a5fca7383b8ef10f37f5e9ad | INFORMATION TO USERS
This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer.
The quality of this reproduction is dependent up... |
b3a3060bd2570d302b8153bae3e8d704fe4eaed5 | Xerox Basic FORTRAN and Basic FORTRAN IV
Sigma 2/3 Computers
Language and Operations
Reference Manual
90 09 67D
August 1970
Price: $2.25
REVISION
This publication is a revision of the Xerox Basic FORTRAN/Basic FORTRAN IV Reference Manual for Sigma 2/3 computers, Publication Number 90 09 67C (dated August, 1968). ... |
4c60567e64918c82beb5dd11f283a24c14a61d83 | Get FREE Compiled Books, Notes, Programs, Books, Question Papers with Solution* etc of following subjects from https://www.tutorialsduniya.com.
- C and C++
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- Android Program... |
9bed5719598ae405eaff7f2897504126474b091a | A network based approach to exact and inexact graph matching
B.T. Messmer, H. Bunke
Institut für Informatik und angewandte Mathematik
Universität Bern
September 20, 1993
Abstract
In this paper a new approach to exact and inexact graph matching is introduced. We propose a compact network representation for graphs, w... |
4086dd83f9322f208a6fc04c82d335de70dcf844 | AWS Well-Architected Framework
AWS Well-Architected Framework
# Table of Contents
Abstract and Introduction ........................................................................................................... 1
Abstract .............................................................................................. |
9c43d88cd3efa4b428cc502438e6663530e5460e | Package ‘memisc’
September 8, 2017
Type Package
Title Tools for Management of Survey Data and for the Presentation of Analysis Results
Version 0.99.14.2
Date 2017-09-08
Author Martin Elff (with contributions from Christopher N. Lawrence, Dave Atkins, Jason W. Morgan, Achim Zeileis)
Maintainer Martin Elff <memisc@elff... |
e63fb92780fae089263333b48aa476810250bc93 | Performance Co-Pilot™ User's and Administrator's Guide
Maintained by:
The Performance Co-Pilot Development Team
<pcp@groups.io>
https://pcp.io
Copyright © 2000, 2013 Silicon Graphics, Inc.
Copyright © 2013, 2015, 2016, 2018 Red Hat, Inc.
LICENSE
Permission is granted to copy, distribute, and/or modify this documen... |
75181cc5986fdd623679c4be5643baddb4cc2910 | A Dynamic Deontic Logic for Complex Contracts
Cristian Prisacariu\textsuperscript{a},b, Gerardo Schneider\textsuperscript{b,a}
\textsuperscript{a}Department of Informatics – University of Oslo, Norway
\textsuperscript{b}Department of Computer Science and Engineering – Chalmers | University of Gothenburg, Sweden
Ab... |
5cf5dc608ce18c88d3835802ac149be1d73f2184 | Certificate Translation for Optimizing Compilers
Gilles Barthe
IMDEA Software
and
Benjamin Grégoire and César Kunz and Tamara Rezk
INRIA Sophia Antipolis - Méditerranée
Proof Carrying Code provides trust in mobile code by requiring certificates that ensure the code adherence to specific conditions. The prominent ap... |
8953d64009d910374e0314c379d39e8df9a13231 | ASSIGNMENT OF MASTER’S THESIS
Title: Summarizing Linked Open Data Datasets
Student: Bc. Jana Čabaiová
Supervisor: Ing. Milan Dojčinovski
Study Programme: Informatics
Study Branch: Web and Software Engineering
Department: Department of Software Engineering
Validity: Until the end of summer semester 2016/17
Instruction... |
00a4aebc4d7b35f2559909be52cef547a480af95 | Xilinx is disclosing this user guide, manual, release note, and/or specification (the "Documentation") to you solely for use in the development of designs to operate with Xilinx hardware devices. You may not reproduce, distribute, republish, download, display, post, or transmit the Documentation in any form or by any m... |
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Jonas Holmberg
jhg12006@student.mdh.se
Examiner: Saad Mubeen
Mälardalen University, Västerås, Sweden
Supervisor: Matthias Becker
Mälardalen University, Västerås, Sweden
June 9, 2017
Abstract
Software systems in the automotive domain are gene... |
1d8b59029f319a7c2082a04a7b0f724d02115555 | Using H2O Driverless AI
PATRICK HALL, MEGAN KURKA & ANGELA BARTZ
http://docs.h2o.ai
August 2020: Version 1.9.0
10.1 Linking Datasets .............................................. 44
10.1.1 Selecting Datasets ................................. 44
10.2 Linking Experiments ......................................... 4... |
871645915855c9df7d67afa423c76341f709d639 | AN ABSTRACT OF THE THESIS OF
Nicholas S. Flann for the degree of Master of Science in Computer Science presented on May 1, 1986.
Title: Learning Functional Descriptions From Examples
Abstract approved: Thomas G. Dietterich.
The task of inductive learning from examples places constraints on the representation of trai... |
2fa132bd984036d317ceddfa8fedc3bd12e8032c | Contents
Chapter 1. Getting Started.................................................................1
Installing..........................................................................................2
Configuring Chemistry as an Oxygen External Tool..........................3
Command Line Interface.............. |
d6ba87a46b6e6df6303cfdeb612cc848b8de90f5 | Black-box random testing of the mCRL2 toolset using attribute grammars
Geelen, M.P.H.
Award date:
2014
Disclaimer
This document contains a student thesis (bachelor's or master's), as authored by a student at Eindhoven University of Technology. Student theses are made available in the TU/e repository upon obtaining t... |
9069099953e2c25b843beb8890d81194954834c9 | Abstract
This document describes how to work with Linux containers on Red Hat Enterprise Linux 9 systems using command-line tools such as podman, buildah, skopeo, runc and crun.
# Table of Contents
**RHEL BETA RELEASE** ................................................................. 5
**MAKING OPEN SOURCE MORE INC... |
01eaf61bbbc0376465fc9915fbc9a873f00f6cc7 | On the Monitoring of Decentralized Specifications: Semantics, Properties, Analysis, and Simulation
Antoine El-Hokayem, Yliès Falcone
To cite this version:
HAL Id: hal-02283429
https://hal.science/hal-02283429v2
Submitted on 1 Oct 2019
HAL is a multi-disciplinary open access archive for the deposit and dissemination... |
f6f3954ab1ba97021648e333d186d344603d124e | The Design and Performance Study of Binary Transitive Closure Algorithms
by
Paul L. C. Wu
B.Sc, Simon Fraser University, 1986
A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Master of Science in the School of Computing Science
© Paul L. C. Wu 1988
SIMON FRASER UNIVERSITY
December 1... |
d01b19a012103c1e0b780417d95dcdd835bf05a1 | An Erasable Programmable Read Only Memory Module
for the HP-41 Handheld Computer
ZEPROM Module
An Erasable Programmable Read Only Memory Module
for the HP-41 Handheld Computer
Programmer’s Manual
April 1988
© Zengrange Limited, England, 1988
ZEPROM - Programmer's Manual
Publisher
Zengrange Ltd, Greenfield Road, L... |
6cd025e340900d77c8953fbd0843abff440bff26 | On the analysis of scheduling algorithms for structured parallel computations
Guilherme Rito*1 and Hervé Paulino2
1ETH Zurich, guilherme.teixeira@inf.ethz.ch
2NOVA Laboratory for Computer Science and Informatics, Departamento de Informática, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, herve.pauli... |
72780b51a45aefabed064d3b520eb7546151b6d6 | Abstract
Rules interchanged using the Rule Interchange Format RIF may depend on or be used in combination with RDF data and RDF Schema or OWL ontologies. This document, developed by the Rule Interchange Format (RIF) Working Group, specifies the interoperation between RIF and the data and ontology languages RDF, RDF Sc... |
0b5ff8b52b01d27b08694ef25f87433c2b8701f1 | FEDERAL UNIVERSITY OF SANTA MARIA
TECHNOLOGY CENTER
GRADUATE PROGRAM IN COMPUTER SCIENCE
Michael Guilherme Jordan
BOOSTING SIMD BENEFITS THROUGH A RUN-TIME
AND ENERGY EFFICIENT DLP DETECTION
Santa Maria, RS
2019
Michael Guilherme Jordan
BOOSTING SIMD BENEFITS THROUGH A RUN-TIME AND ENERGY EFFICIENT DLP DETECTION
D... |
f8895a7f864fbd1e67d295f57413127fb0369182 | An Improved Lower Bound for the Time Complexity of Mutual Exclusion*
James H. Anderson and Yong-Jik Kim
Department of Computer Science
University of North Carolina at Chapel Hill
January 2002, Revised September 2002
Abstract
We establish a lower bound of $\Omega(\log N / \log \log N)$ remote memory references for $N... |
25b36930a039b8c6ef7a0c02a71bd5fa44910152 | Abstract
This manual describes how to install and configure MySQL Connector/Python, a self-contained Python driver for communicating with MySQL servers, and how to use it to develop database applications.
The latest MySQL Connector/Python version is recommended for use with MySQL Server version 5.7 and higher.
For n... |
a82439323e255508381dcd76782d83bc9f90048b | The
Connection Machine
System
Programming the NI
Version 7.1
February 1993
Thinking Machines Corporation
Cambridge, Massachusetts
Contents
List of Figures .................................................. ix
About This Manual .............................................. xi
Customer Support ......................... |
f0201f785f7948c0b52bedf748b749ec37574a2b | Abstract
This is the MySQL Globalization extract from the MySQL 8.0 Reference Manual.
For legal information, see the Legal Notices.
For help with using MySQL, please visit the MySQL Forums, where you can discuss your issues with other MySQL users.
Document generated on: 2020-04-02 (revision: 65592)
# Table of Conte... |
8d2ffa961c2bffc66cebf6d067292f3386b4c86b | Package ‘ShortRead’
May 30, 2024
Type Package
Title FASTQ input and manipulation
Version 1.62.0
Description This package implements sampling, iteration, and input of FASTQ files. The package includes functions for filtering and trimming reads, and for generating a quality assessment report. Data are represented as DN... |
afabe0ed4ffaafc6fe44ec33853e77d6936f3139 | Correctness of Concurrent Executions of Closed Nested Transactions in Transactional Memory Systems *
Sathya Peri †
sathya@iitp.ac.in
Indian Institute of Technology Patna, India
K.Vidyasankar
vidya@mun.ca
Memorial University, St John’s, Canada
July 19, 2011
Abstract
A generally agreed upon requirement for correctne... |
bf86a03e6c46363e4ec0fb5747d259cc50cb9b78 | RASTER GRAPHICS DISPLAY LIBRARY
A Final Report of
NASA Grant NAG-1-391
Presented to
NASA Langley Research Center
ACD M/S 124A
Hampton, Virginia 23665
by
Anders Grimsrud
Graduate Research Assistant
Michael B. Stephenson, Ph.D.
Associate Professor
30 June 1987
Engineering Computer Graphics Laboratory
Civil Enginee... |
ab32bdd9eef26e645d019a603e580b676356cde1 | ABBYY® FineReader PDF 15
Руководство для системного администратора
Информация, содержащаяся в этом документе, может быть изменена без предварительного уведомления, и компания ABBYY не берет на себя на этот счет никаких обязательств.
Программное обеспечение, описываемое в этом документе, поставляется в соответствии с ... |
9dcd52ab22f31bd430b5e46f80de5ef12ad8826c | Exception Handling and Classical Logic
Steffen van Bakel
Department of Computing, Imperial College London, 180 Queen’s Gate, London SW7 2BZ, UK
s.vanbakel@imperial.ac.uk
Abstract
We present $\lambda^{try}$, an extension of the $\lambda$-calculus with named exception handling, via $\text{try}$, $\text{throw}$ and $\t... |
9c72358486f66053130ee5883cec5bb8064f4b4e | An object relational database management system (DMS) permitting a client application (16) to access one or more data sources (14). The client application (16) directs queries to an object server (ObjSvr) component (22), to obtain data from the data sources (14). The ObjSvr component (22) works with an object definitio... |
c572800a5a35991ee61fb38f226fb9ecbdf3e9f8 | Package ‘iSEE’
May 27, 2024
Title Interactive SummarizedExperiment Explorer
Version 2.16.0
Date 2024-04-04
Description Create an interactive Shiny-based graphical user interface for exploring data stored in SummarizedExperiment objects, including row- and column-level metadata. The interface supports transmission of ... |
8f84aa12ac9596ed2ab613d1ac262724ada55b13 | Kentico CMS 5.5 R2 E-commerce Guide
# Table of Contents
## E-commerce Guide
- Kentico CMS E-commerce module ................................................................. 7
## Getting Started
- Making your first purchase ................................................................................. 9
- Adding n... |
b51d2a934b73476739032390c09bb1bf76e5c50a | Improving the Selection of Surrogates During the Cold-Start Phase of a Cyber Foraging Application to Increase Application Performance
Brian Kowalczk
Nova Southeastern University, bkowalczk@hotmail.com
This document is a product of extensive research conducted at the Nova Southeastern University College of Engineering... |
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### Contents
Preface .......................... |
c1e732571eb0bf562555300065ac29f08d0d7058 | Copyright © 2023 Amazon Web Services, Inc. and/or its affiliates. All rights reserved.
Amazon's trademarks and trade dress may not be used in connection with any product or service that is not Amazon's, in any manner that is likely to cause confusion among customers, or in any manner that disparages or discredits Amaz... |
0265a25b8771312c9c28afa3c1eb2e0235fc59dd | GeneralDisclaimer
One or more of the Following Statements may affect this Document
- This document has been reproduced from the best copy furnished by the organizational source. It is being released in the interest of making available as much information as possible.
- This document may contain data, which exceeds t... |
6cd9befc5d594e11a03b357c4a8b552187de4830 | Abstract
This manual describes how to install and configure MySQL Connector/Python, a self-contained Python driver for communicating with MySQL servers, and how to use it to develop database applications.
MySQL Connector/Python 8.0 is highly recommended for use with MySQL Server 8.0, 5.7, and 5.6. Please upgrade to M... |
9f16a75c8b9fbdb350d82fa0971e16e3101bddcf | Katello 3.7 Documentation
1. Installation
1.1 Katello
1.2 Smart proxy
1.3 Clients
2. Upgrade
2.1 Katello
2.2 Smart proxy
2.3 Clients
3. Release Notes
4. CLI
5. User Guide
5.1 Activation Keys
5.2 Backup
5.3 Foreman proxy
5.4 Content
5.5 Content Hosts
5.6 Content Views
5.7 Disconne... |
f23939285f7fc738ee396f92f0404cb71b894898 | Specification Platform for Library IP Development
Jung Kyu Chae
To cite this version:
HAL Id: tel-01126920
https://tel.archives-ouvertes.fr/tel-01126920
Submitted on 6 Mar 2015
HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are publish... |
6cb6e453641b77374df907759d99a81ef33a1dd7 | Maintaining Consistency between a Design Model and Its Implementation
Hector M. Chavez
Western Michigan University, hmch.chavez@gmail.com
Follow this and additional works at: https://scholarworks.wmich.edu/dissertations
Part of the Computer Sciences Commons
Recommended Citation
https://scholarworks.wmich.edu/disser... |
816789d168359a8e810bdcc21915715a7b650ea2 | CBOR Object Signing and Encryption (COSE)
Abstract
Concise Binary Object Representation (CBOR) is a data format designed for small code size and small message size. There is a need for the ability to have basic security services defined for this data format. This document defines the CBOR Object Signing and Encryptio... |
01857f1da7f2c217194761abbef87248cacd2690 | Hybrid Multiparty Session Types - Full Version
Compositionality for Protocol Specification through Endpoint Projection
LORENZO GHERI, University of Oxford, United Kingdom
NOBUKO YOSHIDA, University of Oxford, United Kingdom
Multiparty session types (MPST) are a specification and verification framework for distributed... |
e2a718221a114d12d8e6e2495b0af0e01f137d2b | CA Top Secret® r14 SP1 for z/OS
Security Target
Version 1.1
March 7, 2011
Prepared for:
CA
2400 Cabot Drive
Lisle, IL 60532
Prepared by:
Booz Allen Hamilton
Common Criteria Testing Laboratory
900 Elkridge Landing Road, Suite 100
Linthicum, MD 21090-2950
Table of Contents
1 Security Target Introduction ................ |
46744b86b28c17edc6cfee93ed4da5af447ac87c | Performance tuning of object-relational applications
Zahra Davar
University of Wollongong
UNIVERSITY OF WOLLONGONG
COPYRIGHT WARNING
You may print or download ONE copy of this document for the purpose of your own research or study. The University does not authorise you to copy, communicate or otherwise make availabl... |
3088fd2a179ac20aef0ec717bc04ea7fd56dcf98 | # Table of Contents
Preface .................................................................................................................. 1
Naming ................................................................................................................. 1
Hazelcast IMDG ................................. |
0a80efe5789801f01047c5c6107cd7ef5bbed564 | SYSTEM AND METHOD FOR A CLOUD COMPUTING ABSTRACTION WITH SELF-SERVICE PORTAL FOR PUBLISHING RESOURCES
Applicant: CSC Agility Platform, Inc., Falls Church, VA (US)
Inventors: Frank Martinez, La Canada, CA (US); Eric Pulier, Los Angeles, CA (US)
Assignee: CSC Agility Platform, Inc., Falls Church, VA (US)
Notice: Subj... |
31fc8b62540a7714beb5b480dcfc4128d735a530 | NOTE
Progress is an ongoing commitment at Giddings & Lewis. We continually strive to offer the most advanced products in the industry; therefore, information in this document is subject to change without notice. The illustrations and specifications are not binding in detail. Giddings & Lewis shall not be liable for an... |
6ee26eff68f2e06470f589ae6441af923ef3a838 | Toolkit Feature
Installation and Customization Guide
Release 6
Ninth Edition (July 2008)
This edition applies to IBM High Level Assembler for z/OS & z/VM & z/VSE Toolkit Feature, Release 6, Program Number 5696-234 and to any subsequent releases until otherwise indicated in new editions. Make sure you are using the co... |
f7e6b8ac1c54dc5bbff31b7f3d9f37c0f5953bb4 | Redacted Fields in the Registration Data Access Protocol (RDAP) Response
draft-gould-regext-rdap-redacted-00
Abstract
This document describes an RDAP extension for explicitly identifying
redacted RDAP response fields, using JSONPath as the default
expression language.
Status of This Memo
This Internet-Draft is sub... |
fe12ce0c47f59f7915e2a4d082a11e2a12193c2c | Grammar Transformations for Comparing Modelica Versions
July 1, 2013
Tanya Braun
supervised by:
Prof. Dr. Sibylle Schupp
Dipl.-Ing. Timo Kamph
Hamburg University of Technology (TUHH)
Technische Universität Hamburg-Harburg
Institute for Software Systems
21073 Hamburg
Eidesstattliche Erklärung
Ich versichere an Eide... |
32e1e474743f21cfd0d4aabb4f3f99692e7aadd7 | Serial Attached SCSI RAID Controllers Installation and User's Guide
CDP-00283-01-A Rev. A
Issue: July 15, 2013
### Revision History
<table>
<thead>
<tr>
<th>Issue</th>
<th>Issue Date</th>
<th>Details of Change</th>
</tr>
</thead>
<tbody>
<tr>
<td>1.03</td>
<td>July 15, 2013</td>
<td>Adaptec Firmware/BIOS/Drivers/Util... |
6c0bc88157c4ccc25bafec32664e6599f115f40a | # Chapter 4
## The GA Procedure
<table>
<thead>
<tr>
<th>Contents</th>
<th>Page</th>
</tr>
</thead>
<tbody>
<tr>
<td>Overview: GA Procedure</td>
<td>78</td>
</tr>
<tr>
<td>Getting Started: GA Procedure</td>
<td>80</td>
</tr>
<tr>
<td>Initializing the Problem Data</td>
<td>81</td>
</tr>
<tr>
<td>Choosing the Problem E... |
0dc31022f095b4af7bd6403140d8a7e87aa8bed9 | Abstract
While the OpenShift Container Platform Cluster administration guide is focused more on configuration, this guide will describe an overview of common daily maintenance tasks.
Table of Contents
CHAPTER 1. OVERVIEW ................................................................. 5
CHAPTER 2. RUN-ONCE TASKS ..... |
3911b32500121a348e39be95f0318d671bdf0917 | Licensing and Competition for Services in Open Source Software
Terrence August∗
Rady School of Management
University of California, San Diego
Hyoduk Shin†
Rady School of Management
University of California, San Diego
Tunay I. Tunca‡
Smith School of Business
University of Maryland
March, 2013
Forthcoming in Informa... |
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User Guide
for 2200VP, LVP, MVP, and SVP
2200
Binary Synchronous Communications 1
(BSC 1) User Guide
for 2200VP, LVP, MVP, and SVP
1st Edition — March, 1982
Copyright © Wang Laboratories, Inc., 1982
700-7123
Wang Laboratories, Inc.
One Industrial Avenue, Lowell, Massachuset... |
6ca7aa7951420b6afd73090342da06dfdcb7de6f | **Introduction**
This guide focuses on using ARCCONF with Adaptec Smart Storage Controllers (SmartRAID/SmartHBA/SmartIOC/SmartROC). For information about using ARCCONF with Microchip Adaptec Series 8 (legacy) RAID controllers, see the *Adaptec RAID Controller Command Line Utility User’s Guide* (ESC-2160659).
**Import... |
62ecc43d01a012e7d4104592f595bd7a29b3a8b3 | RASTER GRAPHICS DISPLAY LIBRARY
A Final Report of
NASA Grant NAG-1-391
Presented to
NASA Langley Research Center
ACD M/S 124A
Hampton, Virginia 23665
by
Anders Grimsrud
Graduate Research Assistant
Michael B. Stephenson, Ph.D.
Associate Professor
30 June 1987
Engineering Computer Graphics Laboratory
Civil Engine... |
220e807e0787adb690b2848ad3fa84ecd26fced6 | What is JavaScript?
JavaScript is a dynamic computer programming language. It is lightweight and most commonly used as a part of web pages, whose implementations allow client-side script to interact with the user and make dynamic pages. It is an interpreted programming language with object-oriented capabilities.
Java... |
59c8052f539ebc780c5563e6894ce232a4003d0e | Package ‘sem’
May 19, 2020
Version 3.1-11
Date 2020-05-16
Title Structural Equation Models
Depends R (>= 3.5.0), stats
Imports matrixcalc, MASS, boot, mi (>= 0.9-99), utils
Suggests polycor, DiagrammeR
LazyLoad yes
LazyData yes
ByteCompile yes
Description Functions for fitting general linear structural
equation model... |
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Kishori M Konwar, Wyatt Lloyd, Haonan Lu, Nancy Lynch
November 27, 2018
Abstract
In highly-scalable storage systems for Web services, data is sharded into separate objects, also called shards, across several servers. Transaction isolation, while reading the objects, is at the heart of consi... |
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Transport Subsystem Interface
Reference Guide
DC 900-1386D
Contents
List of Figures .................................................. 7
List of Tables .................................................. 9
Preface ................................................................ 11
1 Overview .................... |
acfd6030ef882a70163bc382d340edf425d13cae | 6.1
Prolog++
Reference
by Dave Westwood
WIN-PROLOG 6.1
The contents of this manual describe the product, BDS-PROLOG for Windows (hereinafter called WIN-PROLOG) and one or more of its LPA Toolkits, and are believed correct at the time of going to press. They do not embody a commitment on the part of Logic Programmin... |
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REQUIREMENTS ANALYSIS AND DESIGN OF A DISTRIBUTED ARCHITECTURE FOR THE COMPUTER AIDED PROTOTYPING SYSTEM (CAPS)
by
Gary L. Kreeger
September 1999
Thesis Advisor: Man-Tak Shing
Approved for public release; distribution is unlimited.
**REPORT DOCUMENTATION PAGE**
1. AGENCY USE ONLY (Leave blank)
2. REPORT D... |
595c61f133c83f54377587cfb2dc18d2139ade75 | Cloud Object Storage
Developer Guide
Product Documentation
Copyright Notice
©2013-2019 Tencent Cloud. All rights reserved.
Copyright in this document is exclusively owned by Tencent Cloud. You must not reproduce, modify, copy or distribute in any way, in whole or in part, the contents of this document without Tencent... |
255532ece3237be85bfb6ef9c04c0411dc9f9eba | 1999
**Embed[ed]ed Zerotree Codec**
Karma Wangdi
*Edith Cowan University*
---
**Follow this and additional works at:** [https://ro.ecu.edu.au/theses_hons](https://ro.ecu.edu.au/theses_hons)
**Part of the Software Engineering Commons**
**Recommended Citation**
---
This Thesis is posted at Research Online. ... |
b77d0c32fa6651a11133530c3304fe2f7d63f56e | LEBANESE AMERICAN UNIVERSITY
SET-BASED APPROACH FOR EFFICIENT EVALUATION AND ANALYSIS OF XACML POLICIES
By
HUSSEIN M. JEBBAOUI
A thesis
Submitted in partial fulfillment of the requirements for the degree of Master of Science in Computer Science
School of Arts and Sciences
May 2014
THESIS APPROVAL FORM
Student Nam... |
7c5a2fc62c1596e969c02dddfabe8a7003c13040 | 1 Megaco/H.248 Users Guide
The Megaco application is a framework for building applications on top of the Megaco/H.248 protocol.
1.1 Introduction
Megaco/H.248 is a protocol for control of elements in a physically decomposed multimedia gateway, enabling separation of call control from media conversion. A Media Gateway... |
f4f748269c168cbfdd4424c938012f56ab31e64a | Bridge Implementation
Version 1 Release 4
Bridge Implementation
*Version 1 Release 4*
Tivoli NetView for OS/390 Bridge Implementation
Copyright Notice
© Copyright IBM Corporation 1997, 2001. All rights reserved. May only be used pursuant to a Tivoli Systems Software License Agreement, an IBM Software License Agree... |
e82dd509154c3200add8d3c73b68f7c4bc34ac36 | CASE STUDY I
FINAL REPORT DEVELOPED FOR LARGE SCALE SOFTWARE SYSTEM DESIGN OF THE AN/TYC-39 STORE AND FORWARD MESSAGE SWITCH USING THE ADA PROGRAMMING LANGUAGE
U. S. ARMY CECOM CONTRACT NO. DAAK80-81-C-0108
VOLUME III OF IV
GENERAL DYNAMICS DATA SYSTEMS DIVISION CENTRAL CENTER P. O. BOX 748 FORT WORTH, TX 76101
DI... |
4f3618dc47deacb05f6fc4e8e607b1d5b3824e49 | LOCKSS System Manual
LOCKSS Program
2023-07-26
The LOCKSS system is a distributed digital preservation software system developed by the LOCKSS Program, a division of the Digital Library Systems and Services department at Stanford University Libraries.
The 2.x series of the LOCKSS system stems from the LAAWS (LOCKSS ... |
b44321ea31b15527f6770b4b22337055b4e7dfca | On Polymorphic Sessions and Functions
A Tale of Two (Fully Abstract) Encodings
Bernardo Toninho and Nobuko Yoshida
Department of Computing, Imperial College London, United Kingdom
Abstract. This work exploits the logical foundation of session types to
determine what kind of type discipline for the π-calculus can exac... |
6d33d35d540b297218287adde2d6284b2cbc42eb | Continuous Integration, Deployment and Testing in DevOps Environment
Anand Srivatsav Amaradri
Swetha Bindu Nutralapati
Faculty of Computing
Blekinge Institute of Technology
SE–371 79 Karlskrona, Sweden
This thesis is submitted to the Faculty of Computing at Blekinge Institute of Technology in partial fulfillment of t... |
37c94f4c43c95d9806a358c0be1a0a3cdb89424b | Automation of retrieval, transformation and uploading of genomic data and their metadata for their integration into a GDM repository
JORGE IGNACIO VERA PENA
MEMORIA DE TITULACIÓN PARA OPTAR AL TÍTULO DE
INGENIERO CIVIL INFORMÁTICO
PROFESOR GUÍA: ANDRÉS MOREIRA
PROFESOR CORREFERENTE: MARCO MASSEROLI
OCTUBRE 2018
A... |
36990ed48137623b7a1706eb9e50f944a2ff772b | Language theory of lambda-calculus with recursive types
Citation for published version (APA):
Language Theory of a $\lambda$–calculus
with Recursive Types
by
H.M.M. ten Eikelder
R.H. Mak
88/14
june 1988
This is a series of notes of the Computing Science Section of the Department of Mathematics and Computing Science ... |
4064e34f1131b673b4a33a98165031070bc0831b |
July 2010
Americas Headquarters
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706
USA
http://www.cisco.com
Tel: 408 526-4000
800 553-NETS (6387)
Fax: 408 527-0883
Text Part Number: OL-23043-01
The Cisco implementation of TCP header compression is an adaptation of a program developed by the University... |
5f328f62829dd36490dc0ddeb7e94bf1c988136e | Minimal Session Types
Alen Arslanagić
University of Groningen, The Netherlands
Jorge A. Pérez
University of Groningen, The Netherlands
Erik Voogd
University of Groningen, The Netherlands
Abstract
Session types are a type-based approach to the verification of message-passing programs. They have been much studied as... |
7dde90c06111c22b1f6a28be1fe2e74fb5870c33 | Keywords: behavioral subtype, subtyping, equational logic, proof theory.
1991 Mathematics Subject Classification. Primary: 68Q65 Secondary: 68N05, 68N15, 68Q60.
Submitted for publication.
Copyright © Gary T. Leavens and Don Pigozzi, 2002.
Department of Computer Science
226 Atanasoff Hall
Iowa State University
Ames... |
4ea6fb41a7e9412aae5720b87140f9cf3885a2e8 | Notices
© 2014 Progress Software Corporation and/or its subsidiaries or affiliates. All rights reserved.
These materials and all Progress® software products are copyrighted and all rights are reserved by Progress Software Corporation. The information in these materials is subject to change without notice, and Progres... |
5d91054894b3e0ae1537b7c25f7dc5edb09160b2 | Table of Contents
1. Setup a development system ................................................................. 1
1.1. Operating System/Environment ......................................................... 1
1.2. Installation ........................................................................................ |
2c929723d78647863c1620bdb92d2b99a26f89ba | Software Program
Software Management Guidebook
November 1996
Foreword
This document is a product of the National Aeronautics and Space Administration (NASA) Software Program, an Agency-wide program to promote continual improvement of software engineering within NASA. The goals and strategies for this program are doc... |
e2b71d7031ec6ca7a5b171920e8c6edd35bd7d02 | EEPROM Emulation Library
Type T02 (Tiny), European Release
16 Bit Single-chip Microcontroller
RL78 Family
Installer:
RENESAS_RL78_EEL-FDL_T02_PACK02_xVxx
All information contained in these materials, including products and product specifications, represents information on the product at the time of publication and ... |
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